Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 08/31/15
AREA FORECAST DISCUSSION
NWS TUCSON AZ
150 PM MST SAT AUG 29 2015
.SYNOPSIS...A CHANCE OF SHOWERS AND THUNDERSTORMS OVER THE WEEKEND
INTO EARLY NEXT WEEK. GRADUALLY DRIER CONDITIONS WILL THEN LIMIT
THUNDERSTORMS TO EAST OF TUCSON THE SECOND HALF OF NEXT WEEK. HOTTER
THAN AVERAGE TEMPERATURES FOR THE NEXT FEW DAYS FOLLOWED BY
TEMPERATURES FALLING TO NEAR AVERAGE AROUND THE MIDDLE OF THE
UPCOMING WEEK.
&&
.DISCUSSION...SATELLITE AND RADAR IMAGERY WERE SHOWING SCATTERED
SHOWERS AND THUNDERSTORMS DEVELOPING ACROSS SOUTHEAST ARIZONA EARLY
THIS AFTERNOON. MOST OF THE ACTIVITY HAS BEEN IN THE MOUNTAINS BUT A
FEW HAVE MANAGED TO DEVELOP OVER THE WESTERN DESERTS OF PIMA COUNTY
AROUND THE TOWNS OF WHY AND AJO. THE WINDS ALOFT REMAINED RATHER
LIGHT SO THE STORMS HAVE BEEN VERY PULSE LIKE IN NATURE WITH LITTLE
MOVEMENT SO FAR. LATEST HRRR CONTINUED TO SHOW SMALL SHOWERS AND
THUNDERSTORMS DOTTED ACROSS MUCH OF SOUTHEAST ARIZONA THROUGH LATE
THIS EVENING. MUCH MORE THAN SUGGESTED BY THE MORNING UPPER-AIR
SOUNDING AT KTWC. AT ANY RATE...LOOKING AT MORE THUNDERSTORM
ACTIVITY COMPARED TO YESTERDAY ALREADY. MODELS SUGGEST ANOTHER
RATHER ACTIVE DAY FOR SUNDAY AS WELL...WITH A LITTLE MORE ORGANIZED
THUNDERSTORMS RATHER THAN PULSE IN NATURE. THEREAFTER...
THUNDERSTORMS WILL DIMINISH IN COVERAGE EACH DAY AS A DRIER
SOUTHWESTERLY FLOW EVOLVES IN RESPONSE TO A LOW PRESSURE SYSTEM
PASSES THROUGH THE NORTHERN TIER STATES. HIGH TEMPERATURES WILL
REMAIN SEVERAL DEGREES ABOVE NORMAL...THEN LOWER TO NEAR SEASONAL
READINGS AROUND WEDNESDAY.
&&
.AVIATION...VALID THRU 31/00Z.
SCT TO LOCALLY BKN CLOUDS AT 8-12 KFT AGL. ISOLD SHRA/TSRA
INCREASING IN COVERAGE THIS AFTERNOON WITH KDUG AND KOLS TERMINALS
LIKELY AFFECTED DIRECTLY. FOR THE KTUS TERMINAL TSRA WILL DEVELOP
OVER THE HIGH TERRAIN AROUND THE AREA WITH A SMALL CHANCE OF ONE
AFFECTING THE TERMINAL 29/22Z THRU 30/02Z. BRIEF MVFR CONDITIONS
AND GUSTY WINDS OF 30 TO 40 KTS WILL BE POSSIBLE IN AND AROUND
STRONGER STORMS. AFTER 30/05Z SKIES CLEARING WITH A REPEAT ON
SUNDAY WITH RESPECT TO CLOUD AND SHRA/TSRA REDEVELOPMENT. OUTSIDE
OF THUNDERSTORM INFLUENCE SURFACE WINDS WILL GENERALLY BE UNDER 10
KTS. AFTER AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE
INTO THE EARLY EVENING BEFORE DYING OFF LATE EVENING HOURS. PRIME
CONCERN IS STRONG WINDS AND HEAVY RAIN DUE TO SLOW MOTIONS. THIS
BASIC IDEA WILL CONTINUE INTO EARLY NEXT WEEK...WITH DAILY AFTERNOON
AND EVENING STORMS EXPECTED. STARTING MONDAY STORMS WILL TEND TO BE
MORE FOCUSED OVER EASTERN ZONES...WITH SIGNIFICANTLY DIMINISHED
THUNDERSTORM ACTIVITY FROM WEDNESDAY ON. THUNDERSTORMS ARE EXPECTED
TO BE WET AND AS IS TYPICAL MAY PRODUCE STRONG...GUSTY AND ERRATIC
WINDS WITH THE STRONGER THUNDERSTORMS.
THROUGH SUNDAY GENERALLY LIGHT TERRAIN DRIVEN WINDS ARE EXPECTED.
FROM MONDAY ONWARD A WEST TO SOUTHWEST FLOW WILL GRADUALLY DEVELOP
ACROSS ARIZONA. THE STRONGEST WINDS WILL BE ACROSS ZONE
150...PEAKING IN THE 15-20 MPH RANGE. THIS FLOW WILL ALSO STEADILY
PUSH THE MOISTURE OUT OF THE REGION FOR DECREASING CHANCES OF
THUNDERSTORMS WEDNESDAY THROUGH FRIDAY.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
908 AM MST SAT AUG 29 2015
.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES WELL ABOVE
SEASONAL NORMALS TODAY WITH HOTTER LOWER DESERTS REACHING OR
EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE EAST OF THE LOWER
COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED AFTERNOON AND
EVENING THUNDERSTORMS THROUGH SUNDAY. STARTING MONDAY DRIER WESTERLY
FLOW ALOFT WILL PUSH THE MOISTURE OFF TO THE EAST LIMITING STORM
CHANCES PRIMARILY TO HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX.
THERE WILL BE A GRADUAL COOLING TREND STARTING SUNDAY WITH CENTRAL
DESERTS HIGH TEMPERATURES DROPPING TO AROUND SEASONAL NORMALS BY THE
MIDDLE OF NEXT WEEK.
&&
.DISCUSSION...
CLEAR TO MOSTLY CLEAR MORNING SKIES PERSIST ACROSS THE FORECAST
AREA...AND ACROSS NEARLY THE WHOLE STATE FOR THAT MATTER...WITH ONLY
SOME FEW TO SCT MID LEVEL CLOUDS ACROSS THE FAR SE CORNER OF AZ.
BROADENING OUT AM SATELLITE LOOPS ACROSS THE WESTERN CONUS...THE
UPPER PACIFIC TROUGH CIRCULATION AND STRONG JET WINDS ARE CLEARLY
EVIDENT OFF THE PAC NW COAST. FURTHER TO THE SOUTH ACROSS THE GREAT
BASIN AND SOUTHWEST SOMEWHAT DRIER ML TO UL CONDITIONS EVIDENT ON
WATER VAPOR...WITH VERY DRY AIR OFF THE SO CAL/NORTHERN BAJA COAST
AND SOMEWHAT STEADY STATE MONSOONAL/TROPICAL AIRMASS OVER NORTHERN
MEXICO. GIVEN THE CLEAR SKIES AND SLIGHTLY DRIER DEWPOINT READINGS
ACROSS THE AREA...AVERAGING 5 TO 10 DEGREES DRIER OVER THIS
MORNING`S HOURS AS COMPARED TO FRIDAY...TEMPERATURES ARE ALREADY
RUNNING WARMER TODAY AND ON TARGET FOR THEIR WELL-ABOVE NORMAL
READINGS AT OR ABOVE THE 110F MARK.
FROM A CONVECTIVE SET-UP TODAY...NO EASILY DISCERNIBLE INVERTED
TROUGH OR STORM MCVS EVIDENT ON THE AM SAT LOOPS. ML AND UL HIGH
CENTERS GENERALLY OFF TO OUR SOUTH RESULTING IN RATHER CHAOTIC BUT
LIGHT FLOW FROM 500MB ON UPWARD. 12Z RAOBS AND ANALYSIS POINT TO A
VERY WEAK WAVE IN THE 500MB/400MB HEIGHT FIELD OVER CENTRAL AZ WITH
FLOW EVENTUALLY TRANSITIONING SOUTHERLY THROUGH THE MIDDAY AND
EVENING HOURS. MODEL STREAMLINE FORECASTS ADVERTISE BROAD AREA OF
UPPER DIFLUENCE PERSISTING FOR SEVERAL HOURS ACROSS PIMA COUNTY AND
SOUTHEASTERN AZ. NAM/GFS 500/400MB STREAMLINES DO SPIN UP SOME
ANTICYCLONIC CIRCULATION OVER CENTRAL AZ DURING MIDDAY BUT
EVENTUALLY ERODE THAT AWAY BY THE AFTERNOON WHILE CREATING SOME
DIFLUENT POCKETS THAT COULD AIDE STORM DEVELOPMENT INTO THE AFTN
OVER THE SOUTH-CENTRAL AZ DESERTS INCLUDING PHOENIX. WEAK MID-LEVEL
STEERING FLOW AND STILL FAVORABLE AIRMASS...WITH AREA PWATS RANGING
FROM 1.25 TO 1.5 INCHES...WILL GENERALLY LEAD TO ISO TO SCT SLOW
MOVING STORMS OVER THE HIGHER ELEVATIONS AND MOUNTAINOUS
TERRAIN...LEAVING THE LOWER DESERT LOCALES AT THE MERCY OF THE
TYPICAL OUTFLOW INTERACTION AND INTERSECTIONS FOR OUR STORM
DEVELOPMENT. LATEST HI-RES FCSTS POINT TO STORMS ON THE SOUTHERN
AND NORTHEASTERN PHX PERIPHERY BY THE AFTN WITH POTENTIAL OUTFLOW
INTRUSIONS AND SUBSEQUENT STORM DEVELOPMENT ACROSS THE PHX METRO
SOMETIME AROUND OR AFTER 5PM LOCAL OR 30/00Z. ONLY MINOR UPDATES
TO THE POP...WEATHER...SKY GRIDS THIS AM TO BLEND IN SOME OF THE
12Z GUIDANCE AND MATCH CURRENT CONDITIONS.
&&
.PREVIOUS DISCUSSION.../ISSUED AT 305 AM MST/PDT...
A STRONG UPPER LEVEL TROF CURRENTLY SPINNING OFF THE
PAC NW COAST HAS KEPT THE DOWNSTREAM UPPER RIDGE PUMPED UP OVER THE
DESERT SOUTHWEST...WITH H5 VALUES AROUND 593DM ACROSS ARIZONA PER
THE LATEST PLOT DATA. THE HIGH HEIGHTS ALOFT CONTINUED TO PRODUCE
HOT WEATHER ACROSS THE LOWER DESERTS WITH PHOENIX REACHING 109
YESTERDAY AND YUMA HITTING 111. LITTLE CHANGE IN THE PATTERN IS
EXPECTED TODAY AND CONTINUED HOT WEATHER IS ON TAP FOR THE LOWER
DESERTS...IN FACT PHOENIX IS EXPECTED TO REACH 110 TODAY WITH 110
PLUS READINGS OVER THE HOTTER WESTERN DESERTS. TEMPERATURES TODAY
WILL BE VERY CLOSE TO EXCESSIVE HEAT WARNING LEVELS.
WITH THE TROFFING SITTING OFF THE WEST COAST AND THE RIDGE PARKED
FIRMLY OVERHEAD...STEERING FLOW IS EITHER WEAK AND NONDESCRIPT OR
WEAK SOUTHERLY. PLENTY OF MOISTURE CONTINUES TO FLOW NORTH THRU
CENTRAL AND EASTERN ARIZONA WITH PWAT VALUES BETWEEN 1.25 AND 1.5
INCHES...AND SURFACE DEWPOINTS REMAIN HIGH AS WELL. AT 2 AM MOST OF
THE LOWER DESERTS RANGED FROM THE MID 50S TO THE MID 60S. EAST OF
THE LOWER COLORADO RIVER TODAY THERE WILL BE SUFFICIENT MOISTURE...
MLCAPE AND DAYTIME HEATING TO KEEP A THREAT GOING FOR AFTERNOON AND
EVENING STORMS...AND IN FACT SEVERAL LOCAL MESOSCALE MODELS
INCLUDING THE HRRR CALL FOR CONVECTION BREAKING OUT THIS AFTERNOON
OVER THE CENTRAL DESERTS...INCLUDING THE GREATER PHOENIX AREA...AND
PERSISTING INTO THE NIGHTTIME HOURS. POPS HAVE BEEN RAISED EAST OF
THE LOWER COLORADO RIVER INTO THE 15-20 PERCENT BALLPARK WITH
CHANCES FORECAST IN THE HIGHER TERRAIN EAST OF PHOENIX.
ON SUNDAY SIGNIFICANT SHORTWAVE ENERGY IS FORECAST TO MOVE INLAND
OVER THE PAC NORTHWEST AND IN RESPONSE FLOW OVER THE DESERT
SOUTHWEST AND ARIZONA BECOMES INCREASINGLY SOUTHWESTERLY. HEIGHTS
ALOFT FALL SLIGHTLY AND TEMPS SHOULD COOL A FEW DEGREES BUT THEY
WILL REMAIN WELL ABOVE NORMAL. THE FLOW WILL START TO SHIFT THE
DEEPER MOISTURE FURTHER TO THE EAST...BUT THERE WILL BE SUFFICIENT
MOISTURE AND INSTABILITY TO KEEP THE THREAT GOING FOR AFTN/EVE STORMS
ACROSS SOUTH CENTRAL ARIZONA. POPS WILL BE SIMILAR TO TODAY...BUT
SLIGHTLY LOWER WEST OF MARICOPA COUNTY.
GFS AND ECMWF OPERATIONAL RUNS AS WELL AS ENSEMBLE GUIDANCE CONTINUE
TO CALL FOR A GRADUAL DRYING AND COOLING TREND TO OCCUR OVER THE
ENTIRE WORK WEEK NEXT WEEK...AS TROFFING ALOFT INITIALLY DEVELOPS
ALONG THE WEST COAST AND PLACES A DRYING SOUTHWEST FLOW ALOFT ACROSS
SERN CALIFORNIA AND ARIZONA. AS THE WEEK PROGRESSES THE TROFFING
STARTS TO PUSH INLAND AND AS THIS HAPPENS TEMPERATURES WILL COOL
DOWN TO NEAR SEASONAL NORMALS. MONDAY INTO TUESDAY THE TROF AXIS
REMAINS ALONG THE WEST COAST...AND FLOW IS NOT SUFFICIENT TO
COMPLETELY SCOUR OUT THE MOISTURE OVER ALL OF SOUTH CENTRAL AZ. FOR
THE MOST PART THE THREAT OF AFTERNOON AND EVENING STORMS WILL BE
CONFINED TO THE HIGHER TERRAIN EAST OF PHOENIX BUT CHANCES IN THE
GREATER PHOENIX AREA WILL CERTAINLY NOT BE ZERO...THEY WILL HOVER IN
THE 5 TO 10 PERCENT BALLPARK. FOR THE LATTER HALF OF THE WORKWEEK AS
THE TROF AXIS SHIFTS INLAND AND SOUTHWEST FLOW ALOFT BECOMES
STRONGER...MOISTURE WILL BE PUSHED OFF TO THE EAST AND EVENTUALLY
ANY THREAT FOR STORMS WILL FOCUS OVER HIGHER TERRAIN AREAS TO THE
EAST OF GLOBE WITH SKIES IN THE GREATER PHOENIX AREA MOSTLY SUNNY
EACH DAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...
EASTERLY FLOW ACROSS THE PHX AREA WILL CONTINUE INTO THE MID
AFTERNOON AS WESTERLY WINDS WILL BE A LITTLE SLOW TO
DEVELOP...LIKELY AFTER 22Z. ENOUGH MOISTURE REMAINS FOR SOME
SHOWERS/STORMS TO DEVELOP OVER THE MTNS OF ARIZONA...INCLUDING WEST
AND SOUTH OF PHX WHICH MAY IMPACT ARRIVAL/DEPARTURE ROUTES.
POSSIBLE...THOUGH NOT ENOUGH TO EXPLICITLY PUT IN TAFS...OF OUTFLOW
COMING IN THIS EVENING PRODUCING SOME BLDU AND PERHAPS A FEW
SHOWERS/STORMS IN THE PHX AREA ITSELF.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
TYPICAL DIURNAL WIND PATTERNS WITH LITTLE CLOUD COVER EXPECTED. FEW
STORMS BETWEEN KBLH-KPHX-KNYL BETWEEN 19Z-01Z.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER... MONDAY THROUGH FRIDAY... OVERALL THE WEATHER
PATTERN WILL BE ON A GENTLE COOLING AND DRYING TREND. FOR MUCH OF
THE WEEK...ANY RAIN CHANCES WILL REMAIN OVER THE HIGHER ELEVATIONS
OF EASTERN ARIZONA. NO SIGNIFICANT WINDS THOUGH THE AFTERNOONS MAY
BE JUST A BIT BREEZIER THAN USUAL.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...NOLTE
PREVIOUS DISCUSSION...CB
AVIATION...INIGUEZ
FIRE WEATHER...INIGUEZ
AREA FORECAST DISCUSSION...UPDATE
NWS PHOENIX AZ
420 AM MST SAT AUG 29 2015
.UPDATE...AVIATION AND FIRE WX SECTION.
&&
.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES WELL ABOVE
SEASONAL NORMALS TODAY WITH HOTTER LOWER DESERTS REACHING OR
EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE EAST OF THE LOWER
COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED AFTERNOON AND
EVENING THUNDERSTORMS THROUGH SUNDAY. STARTING MONDAY DRIER WESTERLY
FLOW ALOFT WILL PUSH THE MOISTURE OFF TO THE EAST LIMITING STORM
CHANCES PRIMARILY TO HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX.
THERE WILL BE A GRADUAL COOLING TREND STARTING SUNDAY WITH CENTRAL
DESERTS HIGH TEMPERATURES DROPPING TO AROUND SEASONAL NORMALS BY THE
MIDDLE OF NEXT WEEK.
&&
.DISCUSSION... A STRONG UPPER LEVEL TROF CURRENTLY SPINNING OFF THE
PAC NW COAST HAS KEPT THE DOWNSTREAM UPPER RIDGE PUMPED UP OVER THE
DESERT SOUTHWEST...WITH H5 VALUES AROUND 593DM ACROSS ARIZONA PER
THE LATEST PLOT DATA. THE HIGH HEIGHTS ALOFT CONTINUED TO PRODUCE
HOT WEATHER ACROSS THE LOWER DESERTS WITH PHOENIX REACHING 109
YESTERDAY AND YUMA HITTING 111. LITTLE CHANGE IN THE PATTERN IS
EXPECTED TODAY AND CONTINUED HOT WEATHER IS ON TAP FOR THE LOWER
DESERTS...IN FACT PHOENIX IS EXPECTED TO REACH 110 TODAY WITH 110
PLUS READINGS OVER THE HOTTER WESTERN DESERTS. TEMPERATURES TODAY
WILL BE VERY CLOSE TO EXCESSIVE HEAT WARNING LEVELS.
WITH THE TROFFING SITTING OFF THE WEST COAST AND THE RIDGE PARKED
FIRMLY OVERHEAD...STEERING FLOW IS EITHER WEAK AND NONDESCRIPT OR
WEAK SOUTHERLY. PLENTY OF MOISTURE CONTINUES TO FLOW NORTH THRU
CENTRAL AND EASTERN ARIZONA WITH PWAT VALUES BETWEEN 1.25 AND 1.5
INCHES...AND SURFACE DEWPOINTS REMAIN HIGH AS WELL. AT 2 AM MOST OF
THE LOWER DESERTS RANGED FROM THE MID 50S TO THE MID 60S. EAST OF
THE LOWER COLORADO RIVER TODAY THERE WILL BE SUFFICIENT MOISTURE...
MLCAPE AND DAYTIME HEATING TO KEEP A THREAT GOING FOR AFTERNOON AND
EVENING STORMS...AND IN FACT SEVERAL LOCAL MESOSCALE MODELS
INCLUDING THE HRRR CALL FOR CONVECTION BREAKING OUT THIS AFTERNOON
OVER THE CENTRAL DESERTS...INCLUDING THE GREATER PHOENIX AREA...AND
PERSISTING INTO THE NIGHTTIME HOURS. POPS HAVE BEEN RAISED EAST OF
THE LOWER COLORADO RIVER INTO THE 15-20 PERCENT BALLPARK WITH
CHANCES FORECAST IN THE HIGHER TERRAIN EAST OF PHOENIX.
ON SUNDAY SIGNIFICANT SHORTWAVE ENERGY IS FORECAST TO MOVE INLAND
OVER THE PAC NORTHWEST AND IN RESPONSE FLOW OVER THE DESERT
SOUTHWEST AND ARIZONA BECOMES INCREASINGLY SOUTHWESTERLY. HEIGHTS
ALOFT FALL SLIGHTLY AND TEMPS SHOULD COOL A FEW DEGREES BUT THEY
WILL REMAIN WELL ABOVE NORMAL. THE FLOW WILL START TO SHIFT THE
DEEPER MOISTURE FURTHER TO THE EAST...BUT THERE WILL BE SUFFICIENT
MOISTURE AND INSTABILITY TO KEEP THE THREAT GOING FOR AFTN/EVE STORMS
ACROSS SOUTH CENTRAL ARIZONA. POPS WILL BE SIMILAR TO TODAY...BUT
SLIGHTLY LOWER WEST OF MARICOPA COUNTY.
GFS AND ECMWF OPERATIONAL RUNS AS WELL AS ENSEMBLE GUIDANCE CONTINUE
TO CALL FOR A GRADUAL DRYING AND COOLING TREND TO OCCUR OVER THE
ENTIRE WORK WEEK NEXT WEEK...AS TROFFING ALOFT INITIALLY DEVELOPS
ALONG THE WEST COAST AND PLACES A DRYING SOUTHWEST FLOW ALOFT ACROSS
SERN CALIFORNIA AND ARIZONA. AS THE WEEK PROGRESSES THE TROFFING
STARTS TO PUSH INLAND AND AS THIS HAPPENS TEMPERATURES WILL COOL
DOWN TO NEAR SEASONAL NORMALS. MONDAY INTO TUESDAY THE TROF AXIS
REMAINS ALONG THE WEST COAST...AND FLOW IS NOT SUFFICIENT TO
COMPLETELY SCOUR OUT THE MOISTURE OVER ALL OF SOUTH CENTRAL AZ. FOR
THE MOST PART THE THREAT OF AFTERNOON AND EVENING STORMS WILL BE
CONFINED TO THE HIGHER TERRAIN EAST OF PHOENIX BUT CHANCES IN THE
GREATER PHOENIX AREA WILL CERTAINLY NOT BE ZERO...THEY WILL HOVER IN
THE 5 TO 10 PERCENT BALLPARK. FOR THE LATTER HALF OF THE WORKWEEK AS
THE TROF AXIS SHIFTS INLAND AND SOUTHWEST FLOW ALOFT BECOMES
STRONGER...MOISTURE WILL BE PUSHED OFF TO THE EAST AND EVENTUALLY
ANY THREAT FOR STORMS WILL FOCUS OVER HIGHER TERRAIN AREAS TO THE
EAST OF GLOBE WITH SKIES IN THE GREATER PHOENIX AREA MOSTLY SUNNY
EACH DAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...
EASTERLY FLOW ACROSS THE PHX AREA WILL CONTINUE INTO THE MID
AFTERNOON AS WESTERLY WINDS WILL BE A LITTLE SLOW TO
DEVELOP...LIKELY AFTER 22Z. ENOUGH MOISTURE REMAINS FOR SOME
SHOWERS/STORMS TO DEVELOP OVER THE MTNS OF ARIZONA...INCLUDING WEST
AND SOUTH OF PHX WHICH MAY IMPACT ARRIVAL/DEPARTURE ROUTES.
POSSIBLE...THOUGH NOT ENOUGH TO EXPLICITLY PUT IN TAFS...OF OUTFLOW
COMING IN THIS EVENING PRODUCING SOME BLDU AND PERHAPS A FEW
SHOWERS/STORMS IN THE PHX AREA ITSELF.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
TYPICAL DIURNAL WIND PATTERNS WITH LITTLE CLOUD COVER EXPECTED. FEW
STORMS BETWEEN KBLH-KPHX-KNYL BETWEEN 19Z-01Z.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER... MONDAY THROUGH FRIDAY... OVERALL THE WEATHER
PATTERN WILL BE ON A GENTLE COOLING AND DRYING TREND. FOR MUCH OF
THE WEEK...ANY RAIN CHANCES WILL REMAIN OVER THE HIGHER ELEVATIONS
OF EASTERN ARIZONA. NO SIGNIFICANT WINDS THOUGH THE AFTERNOONS MAY
BE JUST A BIT BREEZIER THAN USUAL.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...CB
AVIATION...INIGUEZ
FIRE WEATHER...INIGUEZ
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
305 AM MST SAT AUG 29 2015
.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES WELL ABOVE
SEASONAL NORMALS TODAY WITH HOTTER LOWER DESERTS REACHING OR
EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE EAST OF THE LOWER
COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED AFTERNOON AND
EVENING THUNDERSTORMS THROUGH SUNDAY. STARTING MONDAY DRIER WESTERLY
FLOW ALOFT WILL PUSH THE MOISTURE OFF TO THE EAST LIMITING STORM
CHANCES PRIMARILY TO HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX.
THERE WILL BE A GRADUAL COOLING TREND STARTING SUNDAY WITH CENTRAL
DESERTS HIGH TEMPERATURES DROPPING TO AROUND SEASONAL NORMALS BY THE
MIDDLE OF NEXT WEEK.
&&
.DISCUSSION... A STRONG UPPER LEVEL TROF CURRENTLY SPINNING OFF THE
PAC NW COAST HAS KEPT THE DOWNSTREAM UPPER RIDGE PUMPED UP OVER THE
DESERT SOUTHWEST...WITH H5 VALUES AROUND 593DM ACROSS ARIZONA PER
THE LATEST PLOT DATA. THE HIGH HEIGHTS ALOFT CONTINUED TO PRODUCE
HOT WEATHER ACROSS THE LOWER DESERTS WITH PHOENIX REACHING 109
YESTERDAY AND YUMA HITTING 111. LITTLE CHANGE IN THE PATTERN IS
EXPECTED TODAY AND CONTINUED HOT WEATHER IS ON TAP FOR THE LOWER
DESERTS...IN FACT PHOENIX IS EXPECTED TO REACH 110 TODAY WITH 110
PLUS READINGS OVER THE HOTTER WESTERN DESERTS. TEMPERATURES TODAY
WILL BE VERY CLOSE TO EXCESSIVE HEAT WARNING LEVELS.
WITH THE TROFFING SITTING OFF THE WEST COAST AND THE RIDGE PARKED
FIRMLY OVERHEAD...STEERING FLOW IS EITHER WEAK AND NONDESCRIPT OR
WEAK SOUTHERLY. PLENTY OF MOISTURE CONTINUES TO FLOW NORTH THRU
CENTRAL AND EASTERN ARIZONA WITH PWAT VALUES BETWEEN 1.25 AND 1.5
INCHES...AND SURFACE DEWPOINTS REMAIN HIGH AS WELL. AT 2 AM MOST OF
THE LOWER DESERTS RANGED FROM THE MID 50S TO THE MID 60S. EAST OF
THE LOWER COLORADO RIVER TODAY THERE WILL BE SUFFICIENT MOISTURE...
MLCAPE AND DAYTIME HEATING TO KEEP A THREAT GOING FOR AFTERNOON AND
EVENING STORMS...AND IN FACT SEVERAL LOCAL MESOSCALE MODELS
INCLUDING THE HRRR CALL FOR CONVECTION BREAKING OUT THIS AFTERNOON
OVER THE CENTRAL DESERTS...INCLUDING THE GREATER PHOENIX AREA...AND
PERSISTING INTO THE NIGHTTIME HOURS. POPS HAVE BEEN RAISED EAST OF
THE LOWER COLORADO RIVER INTO THE 15-20 PERCENT BALLPARK WITH
CHANCES FORECAST IN THE HIGHER TERRAIN EAST OF PHOENIX.
ON SUNDAY SIGNIFICANT SHORTWAVE ENERGY IS FORECAST TO MOVE INLAND
OVER THE PAC NORTHWEST AND IN RESPONSE FLOW OVER THE DESERT
SOUTHWEST AND ARIZONA BECOMES INCREASINGLY SOUTHWESTERLY. HEIGHTS
ALOFT FALL SLIGHTLY AND TEMPS SHOULD COOL A FEW DEGREES BUT THEY
WILL REMAIN WELL ABOVE NORMAL. THE FLOW WILL START TO SHIFT THE
DEEPER MOISTURE FURTHER TO THE EAST...BUT THERE WILL BE SUFFICIENT
MOISTURE AND INSTABILITY TO KEEP THE THREAT GOING FOR AFTN/EVE STORMS
ACROSS SOUTH CENTRAL ARIZONA. POPS WILL BE SIMILAR TO TODAY...BUT
SLIGHTLY LOWER WEST OF MARICOPA COUNTY.
GFS AND ECMWF OPERATIONAL RUNS AS WELL AS ENSEMBLE GUIDANCE CONTINUE
TO CALL FOR A GRADUAL DRYING AND COOLING TREND TO OCCUR OVER THE
ENTIRE WORK WEEK NEXT WEEK...AS TROFFING ALOFT INITIALLY DEVELOPS
ALONG THE WEST COAST AND PLACES A DRYING SOUTHWEST FLOW ALOFT ACROSS
SERN CALIFORNIA AND ARIZONA. AS THE WEEK PROGRESSES THE TROFFING
STARTS TO PUSH INLAND AND AS THIS HAPPENS TEMPERATURES WILL COOL
DOWN TO NEAR SEASONAL NORMALS. MONDAY INTO TUESDAY THE TROF AXIS
REMAINS ALONG THE WEST COAST...AND FLOW IS NOT SUFFICIENT TO
COMPLETELY SCOUR OUT THE MOISTURE OVER ALL OF SOUTH CENTRAL AZ. FOR
THE MOST PART THE THREAT OF AFTERNOON AND EVENING STORMS WILL BE
CONFINED TO THE HIGHER TERRAIN EAST OF PHOENIX BUT CHANCES IN THE
GREATER PHOENIX AREA WILL CERTAINLY NOT BE ZERO...THEY WILL HOVER IN
THE 5 TO 10 PERCENT BALLPARK. FOR THE LATTER HALF OF THE WORKWEEK AS
THE TROF AXIS SHIFTS INLAND AND SOUTHWEST FLOW ALOFT BECOMES
STRONGER...MOISTURE WILL BE PUSHED OFF TO THE EAST AND EVENTUALLY
ANY THREAT FOR STORMS WILL FOCUS OVER HIGHER TERRAIN AREAS TO THE
EAST OF GLOBE WITH SKIES IN THE GREATER PHOENIX AREA MOSTLY SUNNY
EACH DAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND..
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
EXCEPT FOR VERY ISOLATED THUNDERSTORMS OVER THE MOUNTAINS OF EASTERN
ARIZONA...EXPECT QUIET CONDITIONS THE REST OF THE NIGHT AND THROUGH
THE MORNING. RENEWED STORM DEVELOPMENT OVER HIGHER TERRAIN AND
SOUTHEAST ARIZONA SATURDAY AFTERNOON WITH ONLY A SLIGHT CHANCE OF
STORMS AT ANY GIVEN TAF SITE. OTHERWISE ONLY SOME HIGH CLOUDS ALONG
WITH FAMILIAR DIURNAL WIND PATTERNS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
DRIER AND WARMER WEATHER WILL GRADUALLY SPREAD INTO REGION FROM THE
WEST. A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS WILL STILL BE
FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY. HIGH
TEMPERATURES THROUGH THE WEEK WILL BE NEAR NORMAL WITH HOTTER DESERT
LOCATIONS NEARING 110 ON MONDAY. MINIMUM HUMIDITIES WILL FALL INTO
THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY
ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES
REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST
WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS
EXPECTED.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...CB
AVIATION...AJ
FIRE WEATHER...DEWEY
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
955 PM MST FRI AUG 28 2015
.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES WELL ABOVE
SEASONAL NORMALS THROUGH SATURDAY WITH HOTTER LOWER DESERTS REACHING
OR EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE EAST OF THE LOWER
COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED AFTERNOON AND EVENING
THUNDERSTORMS THROUGH SUNDAY. STARTING MONDAY DRIER WESTERLY FLOW
ALOFT WILL PUSH THE MOISTURE OFF TO THE EAST LIMITING STORM CHANCES
PRIMARILY TO HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX. THERE WILL
BE A GRADUAL COOLING TREND STARTING SUNDAY WITH CENTRAL DESERTS HIGH
TEMPERATURES DROPPING TO AROUND SEASONAL NORMALS BY THE MIDDLE OF
NEXT WEEK.
&&
.DISCUSSION...
STORM ACTIVITY HAS DISSIPATED THIS EVENING ACROSS ARIZONA AND
SOUTHEAST CALIFORNIA. ANTICIPATE THAT TO REMAIN THE CASE OVERNIGHT AS
LOWER LEVELS HAVE HAD SOME DRYING OVER A GOOD PORTION OF
ARIZONA PER 00Z SOUNDINGS...LESS SO OVER SOUTHWEST ARIZONA AND INTO
FAR SOUTHEAST CALIFORNIA. ALSO...SONORA IS FAIRLY QUIET AND NEAREST
LARGE ACTIVITY IS OVER EASTERN NEW MEXICO. THERE COULD BE A STRAY
ISOLATED STORM THANKS TO A LONG TRAVELED GRAVITY WAVE BUT
PROBABILITY TOO LOW TO HOLD ON TO POPS FOR THE OVERNIGHT PERIOD. OF
NOTE...THE LATEST HRRR DOES DEVELOP SOME ACTIVITY OVER SOUTHEAST
ARIZONA WITH SOME VERY ISOLATED STORMS MAKING THEIR WAY INTO SOUTH-
CENTRAL ARIZONA LATE TONIGHT. LOCAL HI-RES MODELS AND 00Z NCAR
ENSEMBLE ARE NOT REFLECTING THAT. LATEST NAM AND GFS INDICATE SOME
RECOVERY OF MOISTURE SATURDAY AND THUS MORE STORMS THAN
TODAY...MAINLY OVER SOUTHEAST ARIZONA. ALSO SOME SOUTHERLY MID LEVEL
WINDS WHICH SHOULD BRING STORMS CLOSER TO THE PHOENIX AREA THAN
TODAY. NO CHANGES TO CURRENT FORECASTS.
&&
.PREVIOUS DISCUSSION ISSUED 152 PM...
AS EXPECTED THERE HAS BEEN A LATER ONSET TO STORM ACTIVITY TODAY
WITH ONLY A FEW SHOWERS AND THUNDERSTORMS IN NORTHERN YUMA COUNTY AND
SOUTHERN RIVERSIDE COUNTY. A FEW ADDITIONAL SHOWERS AND THUNDERSTORMS
ARE CURRENTLY SEEN OVER THE WHITE MOUNTAINS AND NORTH OF THE MOGOLLON
RIM OUTSIDE OF OUR CWA. A BOUNDARY LAYER AND DRYING NORTHERLY FLOW
ALOFT ARE LIMITING DEVELOPMENT CURRENTLY AND LIKELY THROUGH THE REST
OF TODAY. BEST CHANCES FOR THE REST OF TODAY WILL BE OVER HIGHER
TERRAIN AREAS OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA WHERE
PWATS ARE HIGHEST...WHILE LIMITED ACTIVITY ACROSS SOUTHEAST AND
SOUTH-CENTRAL ARIZONA SHOULD MOSTLY STAY OUTSIDE THE PHOENIX AREA.
A SLOW TRANSITION TO A DRIER REGIME IS EXPECTED THROUGH EARLY NEXT
WEEK...BUT STORM CHANCES WILL BE POSSIBLE BOTH SATURDAY AND SUNDAY AS
PWATS ARE FORECAST TO BE AROUND 1.25 INCHES. VERY WEAK FLOW ALOFT ON
SATURDAY POINT TOWARD A TYPICAL MONSOON DAY OVER SOUTH-CENTRAL AND
SOUTHEAST ARIZONA WITH HIGH TERRAIN STORMS FOLLOWED BY THE POTENTIAL
FOR A FEW STORMS OVER THE LOWER DESERTS FROM OUTFLOW INTERACTIONS.
FOR SUNDAY...PWATS START TO DROP BELOW ONE INCH OVER THE LOWER
COLORADO RIVER VALLEY...WHILE STILL REMAINING BETWEEN 1.25-1.40
INCHES OVER SOUTH-CENTRAL ARIZONA. MORE FAVORABLE DIFLUENT FLOW ALOFT
IS LIKELY ON SUNDAY OVER SOUTH-CENTRAL ARIZONA WHICH SHOULD LEAD TO
SLIGHTLY BETTER STORM CHANCES OVER THE LOWER DESERTS. TEMPERATURES
THROUGH THE WEEKEND WILL REMAIN QUITE WARM FOR THIS TIME OF YEAR AS
HIGHS LIKELY WILL BREACH 110 DEGREES IN OUR WESTERN ZONES AND IN A
104-109 RANGE OVER THE SOUTH-CENTRAL ARIZONA DESERTS.
THE DRYING TREND WILL GAIN STEAM STARTING MONDAY AND CONTINUE THROUGH
AT LEAST THE MIDDLE OF NEXT WEEK. UPPER TROFFING IS FORECAST TO SET
UP BOTH ALONG THE WEST COAST AND INLAND OVER THE PAC NORTHWEST AND
THIS WILL LEAD TO STRENGTHENING SOUTHWEST FLOW ALOFT TO WORK INTO THE
DESERT SOUTHWEST AND GRADUALLY THIN OUT THE MOISTURE OVER SE
CALIFORNIA AND THE LOWER AZ DESERTS. BY NEXT MONDAY THUNDERSTORM
CHANCES SHOULD BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS EAST OF
PHOENIX...ZONE 24 TO BE EXACT. THERE WILL BE PERIODS OF HIGH CLOUDS
MOVING THROUGH THE FLOW BUT OVERALL DESERTS SHOULD RANGE FROM MOSTLY
SUNNY TO PARTLY SUNNY EACH DAY FROM MONDAY ONWARD. AS THE UPPER
TROFFING DEVELOPS AND HEIGHTS FALL...HIGH TEMPERATURES WILL STEADILY
FALL OFF AND BY NEXT MONDAY THE WARMER LOWER DESERTS WILL BE WELL
UNDER 110. THE GREATER PHOENIX AREA IS FORECAST TO DROP TO 105 ON
MONDAY...AND EVENTUALLY TO 103 ON WEDNESDAY AND THURSDAY. THE 103
DEGREE READINGS WILL EQUAL THE CLIMATE NORMALS FOR THOSE DAYS.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND..
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
EXCEPT FOR VERY ISOLATED THUNDERSTORMS OVER THE MOUNTAINS OF EASTERN
ARIZONA...EXPECT QUIET CONDITIONS THE REST OF THE NIGHT AND THROUGH
THE MORNING. RENEWED STORM DEVELOPMENT OVER HIGHER TERRAIN AND
SOUTHEAST ARIZONA SATURDAY AFTERNOON WITH ONLY A SLIGHT CHANCE OF
STORMS AT ANY GIVEN TAF SITE. OTHERWISE ONLY SOME HIGH CLOUDS ALONG
WITH FAMILIAR DIURNAL WIND PATTERNS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
DRIER AND WARMER WEATHER WILL GRADUALLY SPREAD INTO REGION FROM THE
WEST. A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS WILL STILL BE
FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY. HIGH
TEMPERATURES THROUGH THE WEEK WILL BE NEAR NORMAL WITH HOTTER DESERT
LOCATIONS NEARING 110 ON MONDAY. MINIMUM HUMIDITIES WILL FALL INTO
THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY
ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES
REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST
WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS
EXPECTED.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ
PREVIOUS DISCUSSION...KUHLMAN/CB
AVIATION...AJ
FIRE WEATHER...DEWEY
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
1048 AM PDT SAT AUG 29 2015
.SYNOPSIS...MUCH COOLER WEATHER IS FORECAST FOR THIS WEEKEND INTO
NEXT WEEK. OUTSIDE OF A SLIGHT CHANCE FOR RAIN ALONG THE SONOMA
COAST THIS MORNING...DRY WEATHER IS EXPECTED.
&&
.DISCUSSION...AS OF 09:10 AM PDT SATURDAY...A FRONTAL BOUNDARY
THAT BROUGHT LIGHT PRECIPITATION TO A GOOD PORTION OF THE NORTH
BAY THIS MORNING CONTINUES TO PUSH INLAND. MANY AREAS IN THIS
REGION PICKED UP A FEW HUNDREDTHS OF AN INCH...WHILE DRIER
CONDITIONS PERSIST SOUTH OF THE SAN FRANCISCO BAY AREA. ONCE THIS
BOUNDARY PUSHES FURTHER INLAND LATER THIS MORNING...CHANCES OF
PRECIPITATION WILL DIMINISH. TEMPERATURES REGION-WIDE WILL ALSO BE
MUCH COOLER TODAY COMPARED TO THE PAST FEW DAYS GIVEN THE COOLER
AIR MASS ASSOCIATED WITH THIS FRONTAL PASSAGE. MANY SPOTS WILL BE
A GOOD 10 TO 15 DEGREES COOLER THIS AFTERNOON. NO CHANGES ARE
NEEDED TO THE ONGOING FORECAST AT THIS TIME.
&&
.UPDATE...AS OF 5:40 AM PDT SATURDAY...RADAR CONTINUES TO SHOW A
LACK OF ANY RADAR RETURNS ACROSS THE NORTH BAY OR COASTAL WATERS
AND WITH THE HRRR NOW GREATLY BACKING OFF ON RAINFALL DECIDED TO
REMOVE MENTION OF RAIN FOR MOST OF OUR AREA. DID KEEP A SLIGHT
CHANCE FOR COASTAL SONOMA COUNTY IN CASE SOME LIGHT RAIN FINALLY
HITS THAT AREA. FOR THE REST OF THE CWA...NOW APPEARS THAT WE WILL
STAY DRY THROUGH THE DAY.
&&
.PREV DISCUSSION...AS OF 3:20 AM PDT SATURDAY...COASTAL RADARS
HAVE PICKED UP ECHOES THROUGH THE OVERNIGHT HOURS ALTHOUGH TO THIS
POINT VIRTUALLY ALL HAVE BEEN NORTH OF OUR CWA. LATEST RUN OF THE
HRRR CONTINUES TO BE IN GOOD AGREEMENT WITH PREVIOUS RUNS AND
BRINGS LIGHT RAIN ACROSS THE NORTH BAY THIS MORNING AND
POTENTIALLY DOWN INTO THE SF BAY AREA AS A COLD FRONT MOVES
ACROSS. WILL BE INTERESTING TO SEE HOW WELL THE HRRR ENDS UP
DOING. EARLIER THIS YEAR WE FOUND THAT IN SOME CASES IT NAILED THE
RAINFALL FOR THE DAY WHILE OTHER TIMES IT WOULD BRING RAIN ACROSS
WHILE THE GROUND TRUTH WAS FAR DRIER.
MORE NOTABLE THAN THE POTENTIAL FOR LIGHT RAIN WILL BE MUCH
COOLER WEATHER THIS WEEKEND AS THE MARINE LAYER DEEPENS WHILE THE
FLOW AT THE SURFACE BECOMES MORE WESTERLY. AT THE SAME TIME THE
STRONG RIDGE OF HIGH PRESSURE CENTERED NEAR THE FOUR CORNERS WILL
PROGRESS TO THE EAST AS THE LONGWAVE TROF ADVANCES TO THE COAST.
INLAND SPOTS WILL GENERALLY SEE THE BIGGEST DROPS COMPARED TO
YESTERDAY WITH HIGHS AS MUCH AS 15 TO 20 DEGREES COOLER. COASTAL
TEMPS WILL GENERALLY BE 5 TO 10 DEGREES COOLER. THE FRONTAL
PASSAGE WILL ALSO TRIGGER BREEZY CONDITIONS WITH LOCALLY GUSTY
WESTERLY WINDS.
SYNOPTICALLY THE NEXT 10 DAYS ARE SHAPING UP WITH THE LONGWAVE
PATTERN FAIRLY STAGNANT...TROF OVER THE WEST WITH A RIDGE TO THE
EAST. THIS WILL TRANSLATE TO TEMPS AT OR BELOW NORMAL. ANY
RAINFALL IS EXPECTED TO FALL NORTH OUR OUR REGION. FOR WHAT IT`S
WORTH...THE 16 DAY GFS SHOWS DRY WEATHER AFTER TODAY FOR OUR
ENTIRE AREA.
&&
.AVIATION...AS OF 10:45 AM PDT SATURDAY... CHAOTIC SKIES WITH
VARYING AND INTERMITTENT FLIGHT RULES THIS MORNING. LATEST METARS
REPORTING MIXING OUT AND LIFTING OF CIGS THROUGHOUT THE LOWER
LAYERS... WHICH WILL TRANSITIONS CIGS FROM MVFR TO VFR THROUGH THE
NEXT HOUR OR TWO. SKIES WILL CLEAR BEHIND THE FRONT... WHICH IS
PUSHING INTO THE INLAND NORTHERN BAY AREA NOW. INCREASING CLOUDS
FOR THE SOUTHERN TAF SITES...INC KMRY...KSNS...KWVI AS FRONT
APPROACHES... HOWEVER EXPECTING VFR FOR THESE SITES FOR REMAINDER
OF DAYLIGHT. RETURN OF MARINE LAYER TONIGHT WILL BE SLIGHTLY LATER
THAN AVERAGE... AND WITH CIGS LOWER THAN NORMAL ON AVERAGE. FOR
TONIGHT... MVFR CIGS EXPECTED FOR BAY AREA... IFR CIGS FOR
MONTEREY BAY AREA. OVERALL CONFIDENCE MODERATE.
VICINITY OF KSFO...GRADUALLY IMPROVING CIGS... CLEARING RAPIDLY
BEHIND FRONT. CLEARING CIGS NO LATER THAN 20Z. LAYER RETURNS AFTER
06-8Z TONIGHT.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO... SLIGHTLY LATER CLEARING.
POSBL AS LATE AS 21Z.
MONTEREY BAY AREA TERMINALS... CHAOTIC SKIES THROUGH THE DAY AS
FRONT APPROACHES... HOWEVER CIGS SHOULD PREDOMINATELY BE VFR WITH
SOME BRIEF MVFR CIGS (ABOVE 2000 FT) POSBL THROUGH THE DAY. MARINE
LAYER RETURNS BEHIND THE FRONT.
&&
.BEACHES...AS OF 10:45 AM PDT SATURDAY...A LONG PERIOD WEST SWELL
HAS ARRIVED AND WILL CONTINUE TO ADVANCE ON WEST FACING BEACHES
THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. THESE LONG PERIOD
SWELLS CAN PRODUCE HAZARDOUS RIP CURRENTS THAT CAN QUICKLY PULL
SWIMMERS OUT TO SEA. THE HIGHEST RISK OF HAZARDOUS CONDITIONS WILL
BE THIS WEEKEND WHEN ONSHORE WINDS WEAKEN AND THE PERIOD INCREASES
FROM 15 TO 18 SECONDS. SWIMMERS CAUGHT IN A RIP CURRENT SHOULD
SWIM PARALLEL TO THE COAST TO ESCAPE THE RIP CURRENTS.
&&
.MARINE...AS OF 10:41 AM PDT SATURDAY...FOR TODAY... A FRONTAL
SYSTEM WILL MOVE THROUGH THE AREA. NORTHWEST WINDS WILL INCREASE
IN THE SOUTHERN WATERS THIS AFTERNOON AND OVER THE NORTHERN WATERS
SUNDAY BEHIND THE FRONT. ADDITIONALLY... A LONG PERIOD WEST SWELL
CONTINUES TO MOVE THROUGH THE REGION INTO EARLY NEXT WEEK.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM FROM 3 PM
&&
$$
PUBLIC FORECAST: RGASS/BELL
AVIATION: DRP
MARINE: DRP
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK AND TWITTER AT:
WWW.FACEBOOK.COM/NWSBAYAREA
WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
916 AM PDT SAT AUG 29 2015
.SYNOPSIS...MUCH COOLER WEATHER IS FORECAST FOR THIS WEEKEND INTO
NEXT WEEK. OUTSIDE OF A SLIGHT CHANCE FOR RAIN ALONG THE SONOMA
COAST THIS MORNING...DRY WEATHER IS EXPECTED.
&&
.DISCUSSION...AS OF 09:10 AM PDT SATURDAY...A FRONTAL BOUNDARY
THAT BROUGHT LIGHT PRECIPITATION TO A GOOD PORTION OF THE NORTH
BAY THIS MORNING CONTINUES TO PUSH INLAND. MANY AREAS IN THIS
REGION PICKED UP A FEW HUNDREDTHS OF AN INCH...WHILE DRIER
CONDITIONS PERSIST SOUTH OF THE SAN FRANCISCO BAY AREA. ONCE THIS
BOUNDARY PUSHES FURTHER INLAND LATER THIS MORNING...CHANCES OF
PRECIPITATION WILL DIMINISH. TEMPERATURES REGION-WIDE WILL ALSO BE
MUCH COOLER TODAY COMPARED TO THE PAST FEW DAYS GIVEN THE COOLER
AIR MASS ASSOCIATED WITH THIS FRONTAL PASSAGE. MANY SPOTS WILL BE
A GOOD 10 TO 15 DEGREES COOLER THIS AFTERNOON. NO CHANGES ARE
NEEDED TO THE ONGOING FORECAST AT THIS TIME.
&&
.UPDATE...AS OF 5:40 AM PDT SATURDAY...RADAR CONTINUES TO SHOW A
LACK OF ANY RADAR RETURNS ACROSS THE NORTH BAY OR COASTAL WATERS
AND WITH THE HRRR NOW GREATLY BACKING OFF ON RAINFALL DECIDED TO
REMOVE MENTION OF RAIN FOR MOST OF OUR AREA. DID KEEP A SLIGHT
CHANCE FOR COASTAL SONOMA COUNTY IN CASE SOME LIGHT RAIN FINALLY
HITS THAT AREA. FOR THE REST OF THE CWA...NOW APPEARS THAT WE WILL
STAY DRY THROUGH THE DAY.
&&
.PREV DISCUSSION...AS OF 3:20 AM PDT SATURDAY...COASTAL RADARS
HAVE PICKED UP ECHOES THROUGH THE OVERNIGHT HOURS ALTHOUGH TO THIS
POINT VIRTUALLY ALL HAVE BEEN NORTH OF OUR CWA. LATEST RUN OF THE
HRRR CONTINUES TO BE IN GOOD AGREEMENT WITH PREVIOUS RUNS AND
BRINGS LIGHT RAIN ACROSS THE NORTH BAY THIS MORNING AND
POTENTIALLY DOWN INTO THE SF BAY AREA AS A COLD FRONT MOVES
ACROSS. WILL BE INTERESTING TO SEE HOW WELL THE HRRR ENDS UP
DOING. EARLIER THIS YEAR WE FOUND THAT IN SOME CASES IT NAILED THE
RAINFALL FOR THE DAY WHILE OTHER TIMES IT WOULD BRING RAIN ACROSS
WHILE THE GROUND TRUTH WAS FAR DRIER.
MORE NOTABLE THAN THE POTENTIAL FOR LIGHT RAIN WILL BE MUCH
COOLER WEATHER THIS WEEKEND AS THE MARINE LAYER DEEPENS WHILE THE
FLOW AT THE SURFACE BECOMES MORE WESTERLY. AT THE SAME TIME THE
STRONG RIDGE OF HIGH PRESSURE CENTERED NEAR THE FOUR CORNERS WILL
PROGRESS TO THE EAST AS THE LONGWAVE TROF ADVANCES TO THE COAST.
INLAND SPOTS WILL GENERALLY SEE THE BIGGEST DROPS COMPARED TO
YESTERDAY WITH HIGHS AS MUCH AS 15 TO 20 DEGREES COOLER. COASTAL
TEMPS WILL GENERALLY BE 5 TO 10 DEGREES COOLER. THE FRONTAL
PASSAGE WILL ALSO TRIGGER BREEZY CONDITIONS WITH LOCALLY GUSTY
WESTERLY WINDS.
SYNOPTICALLY THE NEXT 10 DAYS ARE SHAPING UP WITH THE LONGWAVE
PATTERN FAIRLY STAGNANT...TROF OVER THE WEST WITH A RIDGE TO THE
EAST. THIS WILL TRANSLATE TO TEMPS AT OR BELOW NORMAL. ANY
RAINFALL IS EXPECTED TO FALL NORTH OUR OUR REGION. FOR WHAT IT`S
WORTH...THE 16 DAY GFS SHOWS DRY WEATHER AFTER TODAY FOR OUR
ENTIRE AREA.
&&
.AVIATION...AS OF 4:45 AM PDT SATURDAY...LOW CLOUDS THAT CAME IN
EARLIER THIS EVENING IS MIXING OUT AHEAD OF AN APPROACHING FRONTAL
SYSTEM AS SEVERAL AREA METARS ARE CURRENTLY REPORTING SCT CLOUDS.
SATELLITE IMAGE SHOWS LOW CLOUDS ASSOCIATED WITH THE FRONT
JUST OFFSHORE. THUS WIDESPREAD CIGS WILL RETURN TO THE AREA AFTER
14Z BUT CIGS WILL BE HIGHER AT OR ABOVE 1500 FEET. CLEARING TAKES
PLACE BY AFTERNOON AS THE BACK EDGE OF THE FRONT MOVES THROUGH.
BREEZY POST-FRONTAL WEST WINDS POSSIBLE IN THE AFTERNOON.
VICINITY OF KSFO...MVFR CIGS BY 14Z CLEARING BY 21Z.
CONFIDENCE IS MODERATE.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...IFR CIGS WILL LIFT TO MVFR CIGS
AFTER 14-15Z. CIGS ARE EXPECTED TO FURTHER LIFT AND MIX OUT BY
AROUND 18Z. CONFIDENCE IS MODERATE.
&&
.BEACHES...AS OF 4:30 AM PDT SATURDAY...A LONG PERIOD WEST SWELL
HAS ARRIVED AND WILL CONTINUE TO ADVANCE ON WEST FACING BEACHES
THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. THESE LONG PERIOD
SWELLS CAN PRODUCE HAZARDOUS RIP CURRENTS THAT CAN QUICKLY PULL
SWIMMERS OUT TO SEA. THE HIGHEST RISK OF HAZARDOUS CONDITIONS WILL
BE THIS WEEKEND WHEN ONSHORE WINDS WEAKEN AND THE PERIOD INCREASES
FROM 15 TO 18 SECONDS. SWIMMERS CAUGHT IN A RIP CURRENT SHOULD
SWIM PARALLEL TO THE COAST TO ESCAPE THE RIP CURRENTS.
&&
.MARINE...AS OF 09:10 AM PDT SATURDAY...FOR TODAY... A FRONTAL
SYSTEM WILL MOVE THROUGH THE AREA. NORTHWEST WINDS WILL INCREASE
IN THE SOUTHERN WATERS THIS AFTERNOON AND OVER THE NORTHERN WATERS
SUNDAY BEHIND THE FRONT. ADDITIONALLY... A LONG PERIOD WEST SWELL
CONTINUES TO MOVE THROUGH THE REGION INTO EARLY NEXT WEEK.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM FROM 3 PM
&&
$$
PUBLIC FORECAST: RGASS/BELL
AVIATION: W PI
MARINE: DRP
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK AND TWITTER AT:
WWW.FACEBOOK.COM/NWSBAYAREA
WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
540 AM PDT SAT AUG 29 2015
.SYNOPSIS...MUCH COOLER WEATHER IS FORECAST FOR THIS WEEKEND INTO
NEXT WEEK. OUTSIDE OF A SLIGHT CHANCE FOR RAIN ALONG THE SONOMA
COAST THIS MORNING...DRY WEATHER IS EXPECTED.
&&
.UPDATE...AS OF 5:40 AM PDT SATURDAY...RADAR CONTINUES TO SHOW A
LACK OF ANY RADAR RETURNS ACROSS THE NORTH BAY OR COASTAL WATERS AND
WITH THE HRRR NOW GREATLY BACKING OFF ON RAINFALL DECIDED TO
REMOVE MENTION OF RAIN FOR MOST OF OUR AREA. DID KEEP A SLIGHT
CHANCE FOR COASTAL SONOMA COUNTY IN CASE SOME LIGHT RAIN FINALLY
HITS THAT AREA. FOR THE REST OF THE CWA...NOW APPEARS THAT WE WILL
STAY DRY THROUGH THE DAY.
.DISCUSSION...AS OF 3:20 AM PDT SATURDAY...COASTAL RADARS HAVE
PICKED UP ECHOES THROUGH THE OVERNIGHT HOURS ALTHOUGH TO THIS
POINT VIRTUALLY ALL HAVE BEEN NORTH OF OUR CWA. LATEST RUN OF THE
HRRR CONTINUES TO BE IN GOOD AGREEMENT WITH PREVIOUS RUNS AND
BRINGS LIGHT RAIN ACROSS THE NORTH BAY THIS MORNING AND
POTENTIALLY DOWN INTO THE SF BAY AREA AS A COLD FRONT MOVES
ACROSS. WILL BE INTERESTING TO SEE HOW WELL THE HRRR ENDS UP
DOING. EARLIER THIS YEAR WE FOUND THAT IN SOME CASES IT NAILED THE
RAINFALL FOR THE DAY WHILE OTHER TIMES IT WOULD BRING RAIN ACROSS
WHILE THE GROUND TRUTH WAS FAR DRIER.
MORE NOTABLE THAN THE POTENTIAL FOR LIGHT RAIN WILL BE MUCH
COOLER WEATHER THIS WEEKEND AS THE MARINE LAYER DEEPENS WHILE THE
FLOW AT THE SURFACE BECOMES MORE WESTERLY. AT THE SAME TIME THE
STRONG RIDGE OF HIGH PRESSURE CENTERED NEAR THE FOUR CORNERS WILL
PROGRESS TO THE EAST AS THE LONGWAVE TROF ADVANCES TO THE COAST.
INLAND SPOTS WILL GENERALLY SEE THE BIGGEST DROPS COMPARED TO
YESTERDAY WITH HIGHS AS MUCH AS 15 TO 20 DEGREES COOLER. COASTAL
TEMPS WILL GENERALLY BE 5 TO 10 DEGREES COOLER. THE FRONTAL
PASSAGE WILL ALSO TRIGGER BREEZY CONDITIONS WITH LOCALLY GUSTY
WESTERLY WINDS.
SYNOPTICALLY THE NEXT 10 DAYS ARE SHAPING UP WITH THE LONGWAVE
PATTERN FAIRLY STAGNANT...TROF OVER THE WEST WITH A RIDGE TO THE
EAST. THIS WILL TRANSLATE TO TEMPS AT OR BELOW NORMAL. ANY
RAINFALL IS EXPECTED TO FALL NORTH OUR OUR REGION. FOR WHAT IT`S
WORTH...THE 16 DAY GFS SHOWS DRY WEATHER AFTER TODAY FOR OUR
ENTIRE AREA.
&&
.AVIATION...AS OF 4:45 AM PDT SATURDAY...LOW CLOUDS THAT CAME IN
EARLIER THIS EVENING IS MIXING OUT AHEAD OF AN APPROACHING FRONTAL
SYSTEM AS SEVERAL AREA METARS ARE CURRENTLY REPORTING SCT CLOUDS.
SATELLITE IMAGE SHOWS LOW CLOUDS ASSOCIATED WITH THE FRONT
JUST OFFSHORE. THUS WIDESPREAD CIGS WILL RETURN TO THE AREA AFTER
14Z BUT CIGS WILL BE HIGHER AT OR ABOVE 1500 FEET. CLEARING TAKES
PLACE BY AFTERNOON AS THE BACK EDGE OF THE FRONT MOVES THROUGH.
BREEZY POST-FRONTAL WEST WINDS POSSIBLE IN THE AFTERNOON.
VICINITY OF KSFO...MVFR CIGS BY 14Z CLEARING BY 21Z.
CONFIDENCE IS MODERATE.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...IFR CIGS WILL LIFT TO MVFR CIGS
AFTER 14-15Z. CIGS ARE EXPECTED TO FURTHER LIFT AND MIX OUT BY
AROUND 18Z. CONFIDENCE IS MODERATE.
&&
.BEACHES...AS OF 4:30 AM PDT SATURDAY...A LONG PERIOD WEST SWELL
HAS ARRIVED AND WILL CONTINUE TO ADVANCE ON WEST FACING BEACHES
THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. THESE LONG PERIOD
SWELLS CAN PRODUCE HAZARDOUS RIP CURRENTS THAT CAN QUICKLY PULL
SWIMMERS OUT TO SEA. THE HIGHEST RISK OF HAZARDOUS CONDITIONS WILL
BE THIS WEEKEND WHEN ONSHORE WINDS WEAKEN AND THE PERIOD INCREASES
FROM 15 TO 18 SECONDS. SWIMMERS CAUGHT IN A RIP CURRENT SHOULD
SWIM PARALLEL TO THE COAST TO ESCAPE THE RIP CURRENTS.
&&
.MARINE...AS OF 4:30 AM PDT SATURDAY...A FRONTAL SYSTEM WILL MOVE
THROUGH THE AREA TODAY. NORTHWEST WINDS WILL INCREASE IN THE
SOUTHERN WATERS THIS AFTERNOON AND OVER THE NORTHERN WATERS SUNDAY
BEHIND THE FRONT.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM FROM 3 PM
&&
$$
PUBLIC FORECAST: BELL
AVIATION: W PI
MARINE: W PI
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK AND TWITTER AT:
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
500 AM PDT SAT AUG 29 2015
.SYNOPSIS...A PACIFIC WEATHER SYSTEM WILL BRING A CHANCE OF LIGHT
RAIN TO THE NORTHERN PORTION OF OUR DISTRICT INTO THE MORNING
HOURS TODAY. MUCH COOLER WEATHER IS FORECAST FOR THIS WEEKEND.
DRY AND SEASONABLY COOL WEATHER IS EXPECTED NEXT WEEK.
&&
.DISCUSSION...AS OF 3:20 AM PDT SATURDAY...COASTAL RADARS HAVE
PICKED UP ECHOES THROUGH THE OVERNIGHT HOURS ALTHOUGH TO THIS
POINT VIRTUALLY ALL HAVE BEEN NORTH OF OUR CWA. LATEST RUN OF THE
HRRR CONTINUES TO BE IN GOOD AGREEMENT WITH PREVIOUS RUNS AND
BRINGS LIGHT RAIN ACROSS THE NORTH BAY THIS MORNING AND
POTENTIALLY DOWN INTO THE SF BAY AREA AS A COLD FRONT MOVES
ACROSS. WILL BE INTERESTING TO SEE HOW WELL THE HRRR ENDS UP
DOING. EARLIER THIS YEAR WE FOUND THAT IN SOME CASES IT NAILED THE
RAINFALL FOR THE DAY WHILE OTHER TIMES IT WOULD BRING RAIN ACROSS
WHILE THE GROUND TRUTH WAS FAR DRIER.
MORE NOTABLE THAN THE POTENTIAL FOR LIGHT RAIN WILL BE MUCH
COOLER WEATHER THIS WEEKEND AS THE MARINE LAYER DEEPENS WHILE THE
FLOW AT THE SURFACE BECOMES MORE WESTERLY. AT THE SAME TIME THE
STRONG RIDGE OF HIGH PRESSURE CENTERED NEAR THE FOUR CORNERS WILL
PROGRESS TO THE EAST AS THE LONGWAVE TROF ADVANCES TO THE COAST.
INLAND SPOTS WILL GENERALLY SEE THE BIGGEST DROPS COMPARED TO
YESTERDAY WITH HIGHS AS MUCH AS 15 TO 20 DEGREES COOLER. COASTAL
TEMPS WILL GENERALLY BE 5 TO 10 DEGREES COOLER. THE FRONTAL
PASSAGE WILL ALSO TRIGGER BREEZY CONDITIONS WITH LOCALLY GUSTY
WESTERLY WINDS.
SYNOPTICALLY THE NEXT 10 DAYS ARE SHAPING UP WITH THE LONGWAVE
PATTERN FAIRLY STAGNANT...TROF OVER THE WEST WITH A RIDGE TO THE
EAST. THIS WILL TRANSLATE TO TEMPS AT OR BELOW NORMAL. ANY
RAINFALL IS EXPECTED TO FALL NORTH OUR OUR REGION. FOR WHAT IT`S
WORTH...THE 16 DAY GFS SHOWS DRY WEATHER AFTER TODAY FOR OUR
ENTIRE AREA.
&&
.AVIATION...AS OF 4:45 AM PDT SATURDAY...LOW CLOUDS THAT CAME IN
EARLIER THIS EVENING IS MIXING OUT AHEAD OF AN APPROACHING FRONTAL
SYSTEM AS SEVERAL AREA METARS ARE CURRENTLY REPORTING SCT CLOUDS.
SATELLITE IMAGE SHOWS LOW CLOUDS ASSOCIATED WITH THE FRONT
JUST OFFSHORE. THUS WIDESPREAD CIGS WILL RETURN TO THE AREA AFTER
14Z BUT CIGS WILL BE HIGHER AT OR ABOVE 1500 FEET. CLEARING TAKES
PLACE BY AFTERNOON AS THE BACK EDGE OF THE FRONT MOVES THROUGH.
BREEZY POST-FRONTAL WEST WINDS POSSIBLE IN THE AFTERNOON.
VICINITY OF KSFO...MVFR CIGS BY 14Z CLEARING BY 21Z.
CONFIDENCE IS MODERATE.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...IFR CIGS WILL LIFT TO MVFR CIGS
AFTER 14-15Z. CIGS ARE EXPECTED TO FURTHER LIFT AND MIX OUT BY
AROUND 18Z. CONFIDENCE IS MODERATE.
&&
.BEACHES...AS OF 4:30 AM PDT SATURDAY...A LONG PERIOD WEST SWELL
HAS ARRIVED AND WILL CONTINUE TO ADVANCE ON WEST FACING BEACHES
THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. THESE LONG PERIOD
SWELLS CAN PRODUCE HAZARDOUS RIP CURRENTS THAT CAN QUICKLY PULL
SWIMMERS OUT TO SEA. THE HIGHEST RISK OF HAZARDOUS CONDITIONS WILL
BE THIS WEEKEND WHEN ONSHORE WINDS WEAKEN AND THE PERIOD INCREASES
FROM 15 TO 18 SECONDS. SWIMMERS CAUGHT IN A RIP CURRENT SHOULD
SWIM PARALLEL TO THE COAST TO ESCAPE THE RIP CURRENTS.
&&
.MARINE...AS OF 4:30 AM PDT SATURDAY...A FRONTAL SYSTEM WILL MOVE
THROUGH THE AREA TODAY. NORTHWEST WINDS WILL INCREASE IN THE
SOUTHERN WATERS THIS AFTERNOON AND OVER THE NORTHERN WATERS SUNDAY
BEHIND THE FRONT.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM FROM 3 PM
&&
$$
PUBLIC FORECAST: BELL
AVIATION: W PI
MARINE: W PI
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK AND TWITTER AT:
WWW.FACEBOOK.COM/NWSBAYAREA
WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
321 AM PDT SAT AUG 29 2015
.SYNOPSIS...A PACIFIC WEATHER SYSTEM WILL BRING A CHANCE OF LIGHT
RAIN TO THE NORTHERN PORTION OF OUR DISTRICT INTO THE MORNING
HOURS TODAY. MUCH COOLER WEATHER IS FORECAST FOR THIS WEEKEND.
DRY AND SEASONABLY COOL WEATHER IS EXPECTED NEXT WEEK.
&&
.DISCUSSION...AS OF 3:20 AM PDT SATURDAY...COASTAL RADARS HAVE
PICKED UP ECHOES THROUGH THE OVERNIGHT HOURS ALTHOUGH TO THIS
POINT VIRTUALLY ALL HAVE BEEN NORTH OF OUR CWA. LATEST RUN OF THE
HRRR CONTINUES TO BE IN GOOD AGREEMENT WITH PREVIOUS RUNS AND
BRINGS LIGHT RAIN ACROSS THE NORTH BAY THIS MORNING AND
POTENTIALLY DOWN INTO THE SF BAY AREA AS A COLD FRONT MOVES
ACROSS. WILL BE INTERESTING TO SEE HOW WELL THE HRRR ENDS UP
DOING. EARLIER THIS YEAR WE FOUND THAT IN SOME CASES IT NAILED THE
RAINFALL FOR THE DAY WHILE OTHER TIMES IT WOULD BRING RAIN ACROSS
WHILE THE GROUND TRUTH WAS FAR DRIER.
MORE NOTABLE THAN THE POTENTIAL FOR LIGHT RAIN WILL BE MUCH
COOLER WEATHER THIS WEEKEND AS THE MARINE LAYER DEEPENS WHILE THE
FLOW AT THE SURFACE BECOMES MORE WESTERLY. AT THE SAME TIME THE
STRONG RIDGE OF HIGH PRESSURE CENTERED NEAR THE FOUR CORNERS WILL
PROGRESS TO THE EAST AS THE LONGWAVE TROF ADVANCES TO THE COAST.
INLAND SPOTS WILL GENERALLY SEE THE BIGGEST DROPS COMPARED TO
YESTERDAY WITH HIGHS AS MUCH AS 15 TO 20 DEGREES COOLER. COASTAL
TEMPS WILL GENERALLY BE 5 TO 10 DEGREES COOLER. THE FRONTAL
PASSAGE WILL ALSO TRIGGER BREEZY CONDITIONS WITH LOCALLY GUSTY
WESTERLY WINDS.
SYNOPTICALLY THE NEXT 10 DAYS ARE SHAPING UP WITH THE LONGWAVE
PATTERN FAIRLY STAGNANT...TROF OVER THE WEST WITH A RIDGE TO THE
EAST. THIS WILL TRANSLATE TO TEMPS AT OR BELOW NORMAL. ANY
RAINFALL IS EXPECTED TO FALL NORTH OUR OUR REGION. FOR WHAT IT`S
WORTH...THE 16 DAY GFS SHOWS DRY WEATHER AFTER TODAY FOR OUR
ENTIRE AREA.
&&
.AVIATION...AS OF 10:46 PM PDT FRIDAY...LOW CLOUDS HAVE ADVANCED
INTO THE SAN FRANCISCO BAY MUCH FASTER THAN PREVIOUSLY FORECAST.
HOWEVER...LOW CLOUDS HAVE NOT YET IMPACTED THE MONTEREY
TERMINALS...BUT ARE EXPECTED TO SHORTLY. THERE IS A FRONT MOVING
TOWARD THE COAST TONIGHT WHICH WILL LIFT THE LOW CLOUDS TO MVFR
SATURDAY MORNING. THE CLOUDS WILL MIX OUT BY LATE MORNING EARLY
AFTERNOON AS THE FRONT PASSES TO THE EAST.
VICINITY OF KSFO...IFR BASES BKN-OVC009 HAVE ARRIVE AT THE
TERMINALS FOR THE EVENING. THESE CLOUDS WILL LIFT AND BECOME
CUMULUS TYPE CLOUDS BEGINNING AROUND 1600Z AS THE FRONT
APPROACHES THE TERMINALS. THE CLOUDS WILL FURTHER LIFT AND MIX OUT
BETWEEN 1800 AND 2000Z.
CONFIDENCE IS MODERATE.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR IS ANTICIPATED TO GIVE WAY TO
MVFR BKN-OVC015 BY AROUND 0800Z FURTHER DETERIORATING TO IFR BKN-
OVC008 BY AROUND 1100Z. CLOUDS ARE EXPECTED TO LIFT AND BECOME
MORE CUMULUS TYPE BEGINNING AROUND 1500Z AS THE FRONT APPROACHES
THE TERMINALS. THE CLOUDS ARE ANTICIPATED TO FURTHER LIFT AND MIX
OUT BY AROUND 1800Z
CONFIDENCE IS MODERATE.
&&
.BEACHES...AS OF 11:30 AM PDT FRIDAY...A LONG PERIOD WEST SWELL
HAS ARRIVED AND WILL CONTINUE TO ADVANCE ON WEST FACING BEACHES
THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. THESE LONG PERIOD
SWELLS CAN PRODUCE HAZARDOUS RIP CURRENTS THAT CAN QUICKLY PULL
SWIMMERS OUT TO SEA. THE HIGHEST RISK OF HAZARDOUS CONDITIONS WILL
BE THIS WEEKEND WHEN ONSHORE WINDS WEAKEN AND THE PERIOD
INCREASES FROM 15 TO 18 SECONDS. SWIMMERS CAUGHT IN A RIP CURRENT
SHOULD SWIM PARALLEL TO THE COAST TO ESCAPE THE RIP CURRENTS.
&&
.MARINE...AS OF 3:20 PM PDT FRIDAY...A FRONTAL SYSTEM WILL MOVE
THROUGH THE AREA TODAY. NORTHWEST WINDS WILL INCREASE IN THE
SOUTHERN WATERS THIS AFTERNOON AND OVER THE NORTHERN WATERS SUNDAY
BEHIND THE FRONT.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM FROM 3 PM
&&
$$
PUBLIC FORECAST: BELL
AVIATION: LARRY
MARINE: W PI
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK AND TWITTER AT:
WWW.FACEBOOK.COM/NWSBAYAREA
WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
846 PM MDT SUN AUG 30 2015
.UPDATE...
ISSUED AT 836 PM MDT SUN AUG 30 2015
UPPER RIDGE CONTINUES TO SLOWLY SHIFT EAST IN ADVANCE OF UPPER
LEVEL TROF ACROSS THE NORTHERN ROCKY MTN STATES. MOISTURE LEVELS
ARE SLOWLY INCREASING FROM WEST TO EAST ACROSS COLORADO WITH STILL
DEEPEST MOISTURE OVER WESTERN CO. SCATTERED LIGHT SHOWERS HAVE
BEEN SLOW TO DEVELOP OVER THE MOUNTAINS THIS EVENING WITH LIGHT
RAINFALL ALONG WITH GUSTY WINDS. SHOWERS HAVE TRIED TO SEND OUT
SOME OUTFLOW BOUNDARIES BUT STILL HAVING A HARD TIME HOLDING
TOGETHER AS THEY ARE MOVING INTO A DRIER AND MORE STABLE AIRMASS
OVER THE EASTERN PLAINS. GIVEN DECENT BLOB OF SHOWERS AND STORMS
NOW OVER WESTERN CO...THIS WILL MOVE INTO OUR MOUNTAINS OVERNIGHT
AND ACROSS THE EAST ON MONDAY. WILL MAKE SOME ADJUSTMENTS TONIGHT
SHOWING THIS INCREASING TREND FOR SHOWERS OVER THE MOUNTAINS.
WILL JUST KEEP ISOLATED POPS OVER THE ADJACENT PLAINS FOR TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 400 PM MDT SUN AUG 30 2015
AT PRESENT TIME ...STILL BARELY UNDER THE INFLUENCE OF A STRONG/VERY
WARM AND MOSTLY DRY POSITIVE TILT UPPER RIDGE. 700-500 MB RIDGE AXIS
IS NOW SHIFTED EAST OF THE FRONT RANGE AS PER LATEST RAP MODEL WITH
FLOW ALOFT BECOMING WEST-SOUTHWESTERLY. UPSTREAM OVER UTAH/WESTERN
WYOMING...STRONGER SWLY FLOW ALOFT WITH AN 80-90KT JET CORE IS
PROGGED TO SLOWLY TRANSLATE EASTWARD OVER NORTHERN COLORADO NEXT 24
HOURS. MID/HIGH-LEVEL MOISTURE ALIGNED WITH THIS JET WILL SPREAD
OVER NORTH CENTRAL COLORADO TONIGHT AND NORTHEAST COLORADO ON
MONDAY. MODEL CROSS SECTIONS AND SOUNDINGS SHOW CONDENSATION LEVELS
LOWERING OVER THE HIGH COUNTRY AS A BAND OF SHOWERS AND T-STORMS
ALIGNED WITH A WEAK MID-LEVEL PERTABATION PASSES OVER THE AREA THIS
EVENING. AT THE SAME TIME THIS DISTURBANCE LIFTS EAST-NORTHEAST
ACROSS THE REMAINDER OF THE FORECAST AREA...SHOULD SEE A WEAK SFC
COLD FRONT SLIDING SOUTH OUT OF WYOMING. PRESSURE RISES BEHIND
THE FRONT DO NOT APPEAR TO BE ALL THAT STRONG AND WITH THE PRE-
FRONTAL ENVIRONMENT AS DRY AS IT IS...ITS PROBABLY NOT UNTIL NELY
BNDRY LAYER WINDS KICK IN AFTER FRONTAL PASSAGE WHEN PRECIP CHANCES
SHOULD GO UP EAST OF THE MTNS. AT THIS TIME...THE POORLY ORGANIZED
FRONT COULD SLIP INTO THE DENVER AREA BY 15Z TOMORROW MORNING...WITH
A RE-ENFORCING SURGE OF SLIGHTLY COOLER AND WETTER NELY FLOW BY
ABOUT MIDDAY. MOSTLY CLOUDY TO OVERCAST SKIES AND SCATTERED POPS ARE
IN ORDER FOR MONDAY. ONE OTHER ISSUE...THIS FRONTAL SURGE IS LIKELY
TO USHER IN THE NEXT BATCH OF WILDFIRE SMOKE FORM WILDFIRES TO OUR
NORTH AND NORTHWEST. NWS AIR QUALITY FORECAST GUIDANCE NOT
INDICATING MUCH IN THE WAY OF SFC AND COLUMN SMOKE ALONG THE FRONT
RANGE...BUT SHOULD ANY RESTRICTION DUE TO SMOKE ITS MORE LIKELY TO
OCCUR LATE IN THE DAY. TEMPERATURES QUITE MILD TONIGHT...WHEN COOLING
OFF BY SEVERAL DEGREES TOMORROW. EXPECT MAX TEMPS ON MONDAY TO
BE NEAR TO SLIGHTLY ABOVE AVERAGE.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 400 PM MDT SUN AUG 30 2015
CLOUDS AND SHOWERS/STORMS WILL GRADUALLY CLEAR FROM WEST TO EAST
MONDAY NIGHT. ON TUESDAY SLIGHT DRYING AND WARMING WILL LEAD TO
DIURNAL CONVECTION OVER THE MOUNTAINS THAT SHOULD PROGRESS NICELY
EASTWARD INTO THE EVENING. CAPES ARE RATHER LOW UNTIL YOU GET OUT
ON THE PLAINS...COULD BE A LOW THREAT OF SEVERE WIND/HAIL OUT EAST
IN THE EVENING.
DRIER AIR COMES IN WEDNESDAY. A LITTLE WIND IN THE MOUNTAINS
SHOULD PEAK TUESDAY NIGHT...BUT ENOUGH LEFT WEDNESDAY FOR ELEVATED
FIRE DANGER ESPECIALLY IN NORTH AND MIDDLE PARKS. THERE SHOULD BE
A MINIMUM OF CONVECTION ON WEDNESDAY AND ESPECIALLY THURSDAY WITH
THE WARMING ALOFT AND DRYING.
PRETTY GOOD MODEL AGREEMENT ON THE SOUTHWEST FLOW CONTINUING
THROUGH SATURDAY...WITH JUST A LITTLE MOISTURE POSSIBLY CREEPING
IN AT LOW LEVELS ON THE PLAINS AND ALOFT FROM THE SOUTHWEST. STILL
LOOKS RELATIVELY DRY OVERALL.
SOME DISAGREEMENT ON THE STRUCTURE OF THE TROUGH OVER THE
NORTHWEST AND SHORTWAVES MOVING ACROSS THE NORTHERN ROCKIES NEXT
WEEKEND...BUT NOT BAD FOR THAT TIME RANGE. MOST OF THE IMPACT IS
HEADED NORTH OF US...BUT IT SHOULD PUSH A SURGE OF COOLER AND
MOISTER...AND POSSIBLY SMOKIER...AIR SOMETIME THIS WEEKEND. THERE
ARE ALSO HINTS OF SOME SUBTROPICAL MOISTURE COMING UP FROM THE
EASTERN PACIFIC...BUT THIS MAY STAY SOUTH AND EAST OF US. THERE
COULD BE AN UPSWING IN CONVECTION FROM SUNDAY INTO EARLY NEXT WEEK
AS THE MOISTURE INCREASES...BUT WE WILL STILL BE FIGHTING THE
STABILITY FROM THE WARMTH ALOFT. MODELS SEEM TO KEEP MOST OF THE
PRECIPITATION FURTHER SOUTH. FOR NOW THE COOLING AND SLIGHT
INCREASE IN POPS FOR SUNDAY WILL DO...MAYBE MORE AFTER
THAT...MAYBE NOT.
&&
.AVIATION...(FOR THE TAFS THROUGH 06Z MONDAY EVENING)
ISSUED AT 836 PM MDT SUN AUG 30 2015
OUTFLOW BOUNDARIES TRYING TO WORK OFF THE FOOTHILLS BUT NOT
MAKING MUCH PROGRESS TOWARDS APA/DEN. DECENT OUTFLOW HAS MOVED
SOUTH OFF THE CYS RIDGE SO WATCH TO SEE IF THIS STAYS TOGETHER FOR
LATER THIS EVENING. EXPECT INCREASING MID LEVEL MOISTURE
OVERNIGHT AND COULD BE A FEW SPRINKLES. BETTER CHANCE FOR SHOWERS
WILL HOLD OFF UNTIL AFTER FRONT PASSAGE AROUND MID-LATE MORNING.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ENTREKIN
SHORT TERM...BAKER
LONG TERM...GIMMESTAD
AVIATION...ENTREKIN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1122 PM MDT FRI AUG 28 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 242 PM MDT FRI AUG 28 2015
TODAY AN UPR RIDGE IS OVR UT AND WRN CO...WITH NW FLOW ALOFT OVR ERN
CO AND A WEAK UPR DISTURBANCE MOVING THRU THE NW FLOW OVR ERN CO AND
WRN KS. THE NAM AND HRRR SHOW ISOLD TO SCT CONVECTION OVR THE HYR
TRRN AND PORTIONS OF THE I-25 CORRIDOR THRU THIS EVENING...BUT THE
HRRR ALSO SHOWS THE POTENTIAL FOR A FEW SHOWERS/TSTMS OVR THE SERN
PLAINS AS WELL. HAVE ALREADY SEEN A FEW ECHOES DEVELOP OVR BACA AND
ERN LAS ANIMAS COUNTIES...SO WL KEEP SOME ISOLD POPS FOR THESE
LOCATIONS THIS EVENING...BUT WL KEEP SILENT POPS OVR THE REST OF THE
SERN PLAINS. THE DISTURBANCE WILL EXIT THE REGION IN THE
EVENING...AND PCPN CHANCES ACRS THE AREA ARE GENERALLY EXPECTED TO
END BY MIDNIGHT.
ON SATURDAY THE UPR RIDGE MOVES OVR THE AREA. WITH LIMITED
MOISTURE...ONLY ISOLD TO SCT PCPN CHANCES ARE EXPECTED OVR THE NR
THE HYR TRRN. HIGH TEMPS SATURDAY SHOULD BE AROUND TO SLIGHTLY
ABOVE AVERAGE.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 242 PM MDT FRI AUG 28 2015
MODELS IN DECENT AGREEMENT THROUGH THE EXTENDED PERIOD WITH LOW
ENSEMBLE SPREADS. THE UPPER PATTERN WILL REMAIN NEARLY STATIONARY
WITH RIDGING NORTHWARD OUT OF THE DESERT SOUTHWEST...STRETCHING
NORTHEAST INTO THE NORTHERN PLAINS...AND AN UPPER TROUGH SITS
ALONG THE WEST COAST. EXPECT PERSISTENT SOUTHWESTERLY FLOW ALONG
WITH MONSOONAL MOISTURE TO CONTINUE ACROSS COLORADO THROUGH THE
EXTENDED PERIOD. SHOWER AND THUNDERSTORM CHANCES WILL BE HIGHLY
DEPENDENT UPON EMBEDDED ENERGY IN THE SOUTHWEST FLOW. CURRENT
MODEL ANALYSIS BRINGS NEAR DAILY DISTURBANCES ACROSS THE AREA
SATURDAY NIGHT THROUGH TUESDAY. SHOWERS AND THUNDERSTORMS ARE
FORECAST TO DEVELOP OVER THE MOUNTAINS DURING THE AFTERNOON
HOURS...AND SPREAD EAST INTO THE I-25 CORRIDOR DURING THE EVENING
BEFORE DISSIPATING OVERNIGHT. THE GFS IS DRIER ON WEDNESDAY AND
THURSDAY...AND THE ECMWF IS COMPLETELY DRY THESE DAYS. FOR NOW
HAVE LOW POPS IN THE FORECAST FOR THE MOUNTAINS WEDNESDAY AND
THURSDAY. A STRONGER DISTURBANCE IS LIKELY TO MOVE NORTH OUT OF
THE DESERT SOUTHWEST ON FRIDAY...WITH AN UPTICK IN SHOWER AND
THUNDERSTORM ACTIVITY. SHOWERS AND THUNDERSTORMS WILL BE CAPABLE
OF PRODUCING LOCALLY HEAVY RAINFALL...AND FLASH FLOODING WILL
CONTINUE TO BE A THREAT...ESPECIALLY ON AREA BURN SCARS. TEMPERATURES
WILL REMAIN WARM THROUGH THE EXTENDED PERIOD WITH 80S AND 90S
ACROSS MUCH OF THE AREA FOR AFTERNOON HIGHS. MOZLEY
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1119 PM MDT FRI AUG 28 2015
VFR CONDITIONS ARE ANTICIPATED DURING THE NEXT 24H AT ALL 3 TAF
SITES...KPUB...KALS AND KCOS. WINDS WILL BE DIURNALLY DRIVEN.
THERE WILL BE A VERY SLIGHT CHANCE OF A -TSRA DURING THE AFTERNOON
AND EARLY EVENING HOURS AT ALL 3 TAF SITES...BUT PROBABILITY OF
OCCURRENCE IS TOO LOW TO EXPLICITLY MENTION IN TAF PRODUCT.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...28
LONG TERM...MOZLEY
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS ALBANY NY
415 PM EDT SAT AUG 29 2015
.SYNOPSIS...
HIGH PRESSURE WILL BE OVER NEW YORK AND NEW ENGLAND
THROUGH MOST OF THE WEEKEND WITH TRANQUIL WEATHER. A WEAK WARM FRONT
WILL SPREAD SOME CLOUDS IN TONIGHT INTO EARLY SUNDAY AND PERHAPS
TRIGGER A STRAY SHOWER OR THUNDERSTORM BY SUNDAY AFTERNOON.
THEN...THE HUMIDITY AND HEAT WILL INCREASE AS WE HEAD INTO NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 415 PM EDT...ANOTHER NICE DAY AROUND THE REGION
ALTHOUGH NOT AS CLEAR AS PREVIOUS DAYS. THERE WERE SOME CU AND CI.
HOWEVER...BASED ON SATELLITE PICTURES AND APPROXIMATE TRAJECTORIES...
THINKING THERE WAS ACTUALLY SOME SMOKE ALOFT FROM THE MASSIVE FOREST FIRES
ACROSS THE NORTHWEST.
IT WILL BE INTERESTING TO SEE IF THIS SMOKE HAS ANY BEARING ON
HIGH/LOW TEMPERATURES ON THE DAYS TO COME...BUT EITHER WAY...ITS
EFFECT WILL BE MINIMAL AT BEST.
OTHERWISE...IT WILL BE DRY THROUGH EVENINGWITH ANY SHOWERS...
THE RESULT OF A VERY WEAK SHORT WAVE WELL TO THE NORTH OF CANADIAN/US BORDER...
REMAINING MOSTLY NORTH OF THE REGION.
TEMPERATURES WILL TOP OUT 75-80 HIGHLANDS...80-85 VALLEYS (WARMEST IN THE
MID HUDSON VALLEY). DEWPOINTS HAVE CREPT UP A LITTLE COMPARED TO YESTERDAY...
BUT GENERALLY WERE IN THE UPPER 50S...STILL ON THE COMFORTABLE SIDE.
A FEW LIGHT SHOWERS MIGHT BRUSH NORTHERN HERKIMER COUNTY. (IT SHOULD BE NOTED
THE LATEST HRRR ACTUALLY INDICATED SOME SHOWERS WORKING DOWN THE MOHAWK VALLEY
LATER THIS EVENING). HOWEVER...AT THIS TIME...WE ARE NOT BUYING THIS SOLUTION
SINCE HIGH PRESSURE AND SUBSIDENCE REMAINED OVERHEAD.
WE DO THINK THERE WILL BE A GENERALLY INCREASE IN CLOUDS THIS EVENING AND
ESPECIALLY OVERNIGHT...AHEAD OF AN ADVANCING WARM FRONT. IF THIS IS THE CASE...
OVERNIGHT TEMPERATURES WILL BE MILDER THAN LAST NIGHT...THAT IS ACTUALLY
HOW WE SKETCHED IT OUT IN OUR FORECAST PACKAGE. MOST AREAS WILL RANGE FROM
THE MID 50S TO LOWER 60S TONIGHT.
A SOUTH WIND AROUND 10 MPH...WILL BECOME LIGHT AND VARIABLE TONIGHT.
DUE TO MORE CLOUDS THAN PERHAPS PREVIOUS ANTICIPATED WE BACKED OFF A LITTLE
ON OUR THINKING OF FOG FOR TONIGHT. FOR NOW...WE CONFIDE IT TO THE MOST
PREVALENT VALLEYS AND JUST CALL IT PATCHY FOG.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
HIGH PRESSURE WILL CONTINUE TO "RULE THE ROOST" FOR AT LEAST THE NEXT SEVERAL
DAYS TO COME. INITIALLY STRONGER AT THE SURFACE...IT WILL ULTIMATELY
STRENGTHEN ALOFT AS WELL AS OFFSHORE THROUGH EARLY IN THE WEEK.
A SOUTHERLY FLOW OF ULTIMATELY MORE HUMID AIR WILL OVERSPREAD THE
REGION. THE LEADING EDGE OF THIS MORE HUMID AIR...A WARM FRONT...
WILL ADVANCE TO OUR REGION EARLY SUNDAY AND TEND TO WASH OUT. STILL...
THIS WILL LEAVE SOME RESIDUAL (MOSTLY HIGH CLOUDS BEHIND). SUNDAY COULD
START OUT RATHER CLOUDY WITH PERHAPS A SPRINKLE OR TWO (NOT IN THE GRIDS
AT THIS TIME).
WE THINK SOME SUNSHINE WILL INCREASE DURING SUNDAY AFTERNOON BUT AGAIN
ANY SMOKE ALOFT COULD HAVE A BEARING ON HUGH TEMPERATURES. EITHER WAY...
IT WILL FEEL MORE HUMID BY AFTERNOON WITH DEWPOINTS GETTING UP INTO THE
LOWER END OF THE 60S...EXCEPT EVEN HIGHER ACROSS OUR SOUTHERN ZONES.
WITH SOME SUNSHINE ANTICIPATED WE LEANED WITH THE WARM MAV
GUIDANCE GIVING US HIGH TEMPERATURES LOWER TO MID 80S IN THE VALLEYS...75-80
HIGHER TERRAIN.
WHILE CONDITIONS WILL NOT BE IDEAL FOR CONVECTION ON SUNDAY AFTERNOON...
THERE WILL BE SOME INSTABILITY...ESPECIALLY SOUTH OF I-90
WHERE SBCAPES COULD REACH 500 J/KG. ALSO THERE WILL BE SOME
SORT OF BOUNDARY (DISSIPATING WARM FRONT) TO ACT AS A FOCUS FOR
CONVECTION. THE ABOVE ALONG WITH INCREASING LOW LEVEL MOISTURE WAS
ENOUGH JUSTIFICATION TO RE-INTRODUCE A 20 POP FOR SHOWERS/THUNDER ON
SUNDAY AFTERNOON. MID LEVEL LAPSES RATE LOOK TO REMAIN MEAGER AT ONLY
AROUND 5.5 C/KM) AND THE WIND FIELD WEAK SO
NO SEVERE THUNDERSTORMS (OR EVEN STRONG FOR THAT MATTER) EXPECTED.
SUNDAY NIGHT SHOULD BE CLEAR TO PARTLY CLOUDY WITH LOWS FROM THE MID 50S TO THE MID
60S...WARMEST IN THE CAPITAL REGION. SINCE THERE LOOK TO BE LESS CLOUDS AND
LITTLE OR NO WIND...FOG MIGHT BE A BETTER BET. FOR NOW THOUGH WE JUST KEPT PATHCY FOG
IN THE CLIMATOLOGICALLY FAVORED REGIONS.
MONDAY LOOKS VERY WARM WITH A GOOD DEAL OF SUNSHINE...SCATTERED MIDDAY
AND AFTERNOON CU. H850 TEMPERATURES WILL BE AROUND +16C TRANSLATING HIGHS
INTO THE 80S (UPPER 80S CAPITAL REGION SOUTHWARD IN THE VALLEYS).
A LIGHT WIND WILL BECOME WEST TO SOUTHWEST 5-10 MPH.
DRY MONDAY NIGHT WITH LOWS GENERALLY IN THE 60S. THE SKY WILL AVERAGE PARTLY CLOUDY
WITH PERHAPS SOME VALLEY FOG (NOT IN THE GRIDS AT THIS TIME).
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
A LARGE UPPER LEVEL RIDGE WILL DOMINATE THE WEATHER THROUGH MOST OF
THE EXTENDED PERIOD...ALLOWING FOR ABOVE NORMAL TEMPERATURES AND
MAINLY DRY WEATHER.
THE UPPER LEVEL RIDGE AXIS WILL BE CENTERED RIGHT THROUGH THE
NORTHEAST FOR TUESDAY INTO WEDNESDAY. 850 HPA AROUND 16-19 DEGREES C
WILL ALLOW FOR DAYTIME TEMPS WELL INTO THE 80S...WITH SOME LOW 90S
EVEN POSSIBLE FOR THE HUDSON VALLEY REGION. OVERNIGHT LOW WILL
MAINLY BE IN THE 60S. ALONG WITH THE WARM TEMPERATURES...IT WILL BE
FAIRLY MUGGY WITH DEWPOINTS INTO THE 60S. DRY WEATHER SHOULD BE IN
PLACE...ALTHOUGH CANNOT RULE OUT AN AFTERNOON SHOWER FOR THE
ADIRONDACKS FOR WED AFTN.
AN UPPER LEVEL DISTURBANCE WILL SLIDE ACROSS THE TOP OF THE RIDGE
ACROSS EASTERN CANADA FOR THURSDAY INTO FRIDAY. THIS FEATURE WILL
PROBABLY BE TOO FAR AWAY FROM OUR AREA TO HAVE A MAJOR IMPACT...BUT
IT COULD PUSH A BACKDOOR SFC BOUNDARY CLOSE ENOUGH TO THE AREA FROM
THE NORTH OR NORTHEAST TO ALLOW A STRAY SHOWER OR THUNDERSTORM TO
DEVELOP IN THE AFTN OR EVENING HOURS. OTHERWISE...DRY AND VERY WARM
WEATHER WILL CONTINUE...WITH HIGHS WELL INTO THE 80S EACH DAY...AND
OVERNIGHT LOWS MAINLY IN THE 60S.
WARM TEMPS WILL CONTINUE FOR THE WEEKEND AS WELL...WITH TEMPS
CONTINUING WELL ABOVE NORMAL. WILL CONTINUE TO FORECAST VALLEY HIGH
TEMPS IN THE MID TO UPPER 80S FOR SAT WITH THE UPPER LEVEL RIDGE
STILL IN PLACE OVER MUCH OF THE CENTRAL AND EASTERN US...WITH NO
PRECIP EXPECTED TO OCCUR.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
RIDGING WILL REMAIN ACROSS THE REGION...HOWEVER THE CENTER
OF THE HIGH WILL GRADUALLY SHIFT OFFSHORE INTO SUNDAY. IN THE
MEANTIME...A SHORT WAVE TROUGH OVER THE GREAT LAKES REGION
WILL MOVE EASTWARD AND DAMPEN OUT AS IT PASSES OVER EASTERN
CANADA.
LOOKING AT VFR CONDITIONS...THE EXCEPTION WILL BE AT KPSF WHERE
SOME FOG IS EXPECTED TO FORM OVERNIGHT AND MAY LOWER TO IFR FOR
A PERIOD LATE AT NIGHT. OTHERWISE...MUCH OF DIURNAL CUMULUS SHOULD
DISSIPATE THIS EVENING WITH HIGH LEVEL CIRRUS CLOUDS CONTINUING
TO STREAM OVERHEAD. MID LEVEL CLOUDS AREA ARE EXPECTED TO MOVE
IN OVERNIGHT. A CEILING OF AROUND 5K IS EXPECTED FOR SUNDAY MORNING.
LIGHT SOUTH TO SOUTHWEST WINDS WILL DIMINISH BECOMING CALM
OVERNIGHT WITH A SOUTHWEST TO WEST FLOW DEVELOPING SUNDAY.
HOWEVER THE FLOW SHOULD BE MORE SOUTHERLY AT KGFL.
OUTLOOK...
SUN NIGHT-WED NIGHT: PATCHY FOG LATE AT NIGHT/EARLY IN THE AM.
THU: LOW OPERATIONAL IMPACT. ISOLATED SHRA...TSRA
&&
.FIRE WEATHER...
NO SIGNIFICANT RAINFALL EXPECTED THROUGH THIS WEEK AS A LARGE HIGH
PRESSURE AREA...NOT ONLY AT THE SURFACE...BUT ALOFT...DOMINANTS
OUR WEATHER.
IN FACT...NOTHING MORE THAN A STRAY SHOWER OR THUNDERSTORM
IS EXPECTED WITH THE BEST CHANCES OF THAT SUNDAY AFTERNOON
AND AGAIN FRIDAY. EVEN THIS WOULD BE THE EXCEPTION THAN THE RULE.
EXPECT NORMAL DIURNAL TRENDS REGARDING THE RH...WITH FULL OR NEARLY
FULL RECOVERY EXPECTED EACH OVERNIGHT. DAYTIME RH VALUES WILL BE MODERATE
GENERALLY IN THE 40-60 PERCENT RANGE.
THE WIND EACH DAY WILL LIGHT AND VARIABLE...MAINLY UNDER 10 MPH.
&&
.HYDROLOGY...
NO HYDROLOGIC ISSUES ARE ANTICIPATED OVER THE NEXT FIVE DAYS.
NO WIDESPREAD RAINFALL IS FORECAST TO FALL FOR AT LEAST THE NEXT
FIVE DAYS AS A RIDGE OF HIGH PRESSURE BUILDS IN.
RIVER LEVELS WILL CONTINUE TO RUN AT OR BELOW NORMAL LEVELS FOR
AUGUST...AND IF ANYTHING...MIGHT DROP A LITTLE MORE.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...FRUGIS
AVIATION...IAA
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
410 PM EDT SAT AUG 29 2015
...HEAVY RAIN THREAT THROUGH MONDAY...
TONIGHT...SURFACE-850 MB SOUTHEAST WINDS WILL INCREASE TO 20-25
KNOTS AS THE REMNANT LOW PRESSURE TROUGH FROM ERIKA MOVES INTO THE
FLORIDA STRAITS. THIS WILL FAVOR CONVERGENCE LINES OFF THE BAHAMAS
AND SOME COASTAL CONVERGENCE. THEREFORE ONCE LINGERING DEBRIS
RAINFALL AND SCATTERED STORMS END THIS EVENING...THERE WILL BE A
GOOD CHANCE FOR SHOWERS AND STORMS ALONG THE COAST OVERNIGHT. THE
LATEST GFS SHOWS THE HIGHEST RAIN AMOUNTS ALONG THE TREASURE
COAST...WITH POPS 50-60 PERCENT AND WILL FOLLOW CLOSE TO MOS VALUES.
SUN...HIGH PRECIPITABLE WATER NEAR 2.25 INCHES WILL ENCOMPASS THE
AREA AS THE LOW PRESSURE TROUGH PUSHES INTO THE SOUTHEAST
GULF. INCREASED LOW LEVEL CONVERGENCE DUE TO THE TROUGH...COMBINED
WITH UPPER LEVEL DIVERGENCE DUE TO MID/UPPER LEVEL TROUGH IN THE
GULF....WILL PRODUCE VERY HIGH RAIN CHANCES AND A THREAT FOR HEAVY
RAIN. THIS IS EVIDENCED BY THE 12Z GFS POPS 80-100 PERCENT AND 12
HOUR QPF VALUES 2 INCHES OR GREATER. THINK THAT THE HEAVY RAIN
CHANCES WILL BE NEAR THE COAST IN THE MORNING THEN TRANSITION TO
THE INTERIOR IN THE AFTERNOON AS MODEST HEATING OCCURS THROUGH
LATE MORNING.
SUN NIGHT...WITH THE HIGH MOISTURE AND STILL BREEZY LOW LEVEL
WINDS...THE CHANCE FOR SHOWERS/STORMS WITH HEAVY RAIN WILL
CONTINUE QUITE HIGH AND HAVE KEPT PREVIOUS POPS WHICH WERE 60
PERCENT.
MON...THE GFS SHOWS SURFACE LOW PRESSURE TROUGH PUSHING FARTHER
OUT INTO THE GULF AROUND 86W. WHILE THE LOW LEVEL WINDS/CONVERGENCE
WILL WEAKEN UNDER THIS SCENARIO...AND UPPER LEVEL DIVERGENCE ALSO
DECREASES...HIGH PRECIPITABLE WATER 2.25 INCHES OR GREATER IS
FORECAST TO CONTINUE. THEREFORE LIKELY POPS INDICATED BY THE MOS
AND INCLUDED IN THE PREVIOUS FORECAST LOOK GOOD. THE THREAT OF
FOR HEAVY RAIN WILL CONTINUE. GFS MODEL AMOUNTS FOR THE SUN-MON
PERIOD ARE 1-3 INCHES AREAWIDE...WHICH LOOKS REASONABLE.
HOWEVER...WITH PRECIPITABLE WATER VALUES 2.25 INCHES THROUGH THE
PERIOD...LOCALLY HIGHER AMOUNTS 3-5 INCHES ARE CERTAINLY POSSIBLE.
TUE-FRI...REMNANT SURFACE TROUGH FROM ERIKA IS FORECAST TO MOVE
SLOWLY IN THE NORTHEAST GULF OF MEXICO OR GRADUALLY WASH OUT.
ATLANTIC SURFACE RIDGE SHOULD EXTEND NORTH OF THE REGION AND
CONTINUE A SOUTHEASTERLY WIND FLOW...WITH MORE TYPICAL LIGHTER
SPEEDS THOUGH. MOISTURE LOOKS ELEVATED WITH LAPSE RATES RATHER
AVERAGE. EXPECT A RETURN TO SCATTERED AFTERNOON/EVENING
SHOWERS/STORMS.
&&
.AVIATION...SCT TSRA FROM KMCO-KDED WILL MOVE WESTWARD INTO LATE
AFTERNOON WITH ADDITIONAL SHRA/TSRA EXPECTED TO DEVELOP FROM KLEE-
KISM INTO EARLY EVENING. HRRR INDICATES SOME CONVECTION MAY PUSH
BACK TO KSFB-KMCO CORRIDOR INTO LATE EVENING WITH MID LVL SW FLOW.
SCATTERED ATLC SHOWERS WILL INCREASE IN COVERAGE AND MOVE ONSHORE
FROM KMLB-KSUA OVERNIGHT WITH TEMPO SHRA EXPECTED FOR THE LATE NIGHT
HOURS PROGRESSING INTO THE INTERIOR BY LATE MORNING ON SUNDAY. MVFR
CIGS AND IFR VSBYS PSBL WITH +SHRA/+TSRA IN CONVECTION.
&&
.MARINE...
TONIGHT...PRESSURE GRADIENT WILL GRADUALLY TIGHTEN AS LOW
PRESSURE TROUGH FROM REMNANTS OF ERIKA LIFTS INTO THE FLORIDA
STRAITS. EAST/SOUTHEAST WINDS WILL INCREASE ENOUGH TONIGHT FOR
EXERCISE CAUTION CONDITIONS IN THE SOUTH. ELSEWHERE THERE WILL BE
MORE WIND CHOP SO CONDITIONS STARTING OUT SUNDAY LOOK POOR FOR
SMALL CRAFT OVER ALL OF THE WATERS.
SUN-MON...THE WEATHER CONDITIONS LOOK POOR WITH SCATTERED TO
NUMEROUS SHOWERS AND STORMS WITH GUSTY WINDS TO 30 KNOTS. OUTSIDE
THE CONVECTION...GRADIENT WILL SUPPORT EXERCISE CAUTION FROM ABOUT
THE CAPE SOUTH ON SUNDAY AND POSSIBLY INTO SUNDAY EVENING.
SOUTHEAST WINDS WILL DIMINISH TO 10-15 KNOTS LATE SUNDAY NIGHT AND
INTO MONDAY.
TUE-WED...HIGH PRESSURE RIDGE ALONG THE EASTERN SEABOARD WILL
CONTINUE TO PRODUCE A SOUTHEAST WIND FLOW BUT SPEEDS LOOK CLOSER
TO 10 KNOTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 77 86 76 86 / 30 70 60 70
MCO 76 89 75 89 / 30 70 50 70
MLB 78 87 77 88 / 30 80 60 70
VRB 78 88 77 88 / 40 80 60 70
LEE 76 92 75 89 / 30 70 40 60
SFB 76 88 75 89 / 30 70 50 70
ORL 76 88 75 88 / 30 70 50 70
FPR 78 89 77 89 / 40 80 60 70
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...FLOOD WATCH THROUGH MONDAY EVENING FOR COASTAL VOLUSIA COUNTY-
INDIAN RIVER-INLAND VOLUSIA COUNTY-MARTIN-NORTHERN BREVARD
COUNTY-NORTHERN LAKE COUNTY-OKEECHOBEE-ORANGE-OSCEOLA-
SEMINOLE-SOUTHERN BREVARD COUNTY-SOUTHERN LAKE COUNTY-ST.
LUCIE.
AM...NONE.
&&
$$
SHORT TERM...LASCODY
LONG TERM....SEDLOCK
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
1006 AM EDT SAT AUG 29 2015
.DISCUSSION...
...A CHANCE FOR HEAVY RAIN ESPECIALLY SUNDAY AND MONDAY...
TODAY/TONIGHT...LOW LEVEL FLOW WILL BE FROM THE EAST/SOUTHEAST WITH
SPEEDS INCREASING TONIGHT...WHICH WILL FAVOR INTERIOR CONVECTION
THIS AFTERNOON AND THE COAST TONIGHT. MID LEVEL FLOW WILL REMAIN
MOSTLY OUT OF THE SOUTH SO SOME DEBRIS RAINFALL FROM AFTERNOON
CONVECTION SHOULD AFFECT THE NORTH COAST LATE IN THE DAY.
MORNING GPS PRECIPITABLE WATER DATA...MIAMI SOUNDING AND GFS
FORECAST SOUNDINGS SHOW SOME ELEVATED DRY AIR. MORNING SATELLITE
SHOWS LITTLE DEEP CONVECTION OFF TO OUR EAST...SO CURRENT FORECAST
FOR TODAY WITH LOWER POPS ALONG THE COAST SOUTH OF THE CAPE LOOKS
GOOD. THE LATEST HRRR MODEL CONCENTRATES THE HEAVY RAIN THIS
AFTERNOON NEAR/WEST OF I-4...WHICH LOOKS GOOD SINCE THIS SEA BREEZE
CONVECTION WILL BE MOVING INTO AN AREA WITH DIVERGENCE ALOFT. THERE
WILL BE A LITTLE MORE STEERING FLOW TODAY SO STORMS SHOULD SHOW A
LITTLE MORE MOTION TO THE NORTH/NORTHWEST...SO EXPECT THE INTERIOR
STORMS WILL HAVE MAX AMOUNTS AROUND 2 INCHES.
SOUTHEAST FLOW INCREASING TONIGHT SHOULD PRODUCE INCREASED SHOWER
AND STORM CHANCES ALONG THE COAST...ESPECIALLY SOUTH OF THE CAPE.
ALL OF THE ABOVE THINKING IS PRETTY MUCH INCORPORATED INTO THE
PREVIOUS FORECAST AND LITTLE CHANGE IS PLANNED.
&&
.AVIATION...MOSTLY VFR THIS MORNING EXCEPT BRIEF MVFR AS CUMULUS
FORM. STILL EXPECT INCREASING COVERAGE OF SHOWERS AND STORMS
PRODUCING TEMPO IFR/MVFR REDUCTIONS MAINLY ACROSS INTERIOR TAF SITES
MID-LATE AFTERNOON.
AREAS OF LINGERING RAIN AND ISOLATED STORMS SHOULD EXTEND THROUGH
EARLY EVENING OVER THE INTERIOR AND POSSIBLY AT DAB. AN INCREASING
MOIST SE FLOW WILL LEAD TO SCATTERED SHRA AND ISOLATED TSRA OVER THE
WATERS THAT WILL PUSH ONSHORE OVERNIGHT...ESPECIALLY AFFECTING
SITES BETWEEN MLB AND SUA.
&&
.MARINE...
TODAY/TONIGHT...PRESSURE GRADIENT WILL GRADUALLY TIGHTEN AS LOW
PRESSURE TROUGH FROM REMNANTS OF ERIKA LIFTS INTO THE FLORIDA
STRAITS. EAST/SOUTHEAST WINDS SHOULD INCREASE ENOUGH TONIGHT FOR
EXERCISE CAUTION CONDITIONS IN THE SOUTH. ELSEWHERE THERE WILL BE
MORE WIND CHOP SO CONDITIONS STARTING OUT SUNDAY LOOK POOR FOR SMALL
CRAFT OVER ALL OF THE WATERS.
SUN-WED...E/SE MARITIME FLOW INCREASES SUN/MON AS REMNANT TROUGH
FROM ERIKA DRAWS NEARER TO THE SW PENINSULA. INCREASE IN FLOW WILL
PROMOTE AREAS OF HEAVY RAIN WITH EMBEDDED STORMS WHICH WILL
SUBSTANTIALLY DROP LOCAL VISIBILITIES AT TIMES ACROSS THE WATERS S
OF THE CAPE. WINDS 15 TO 20 KNOTS SUN WITH SEAS TO 6 FT THERE. WINDS
WILL RELAX A LITTLE GOING INTO MON BUT SEAS WILL BE A LITTLE SLOWER
TO SLACKEN AS SMALL CRAFT WILL BE URGED TO EXERCISE CAUTION THRU
MON. WINDS TO 15 KNOTS NORTH OF THE CAPE BUT WITH THE SAME 6 FT SEAS.
BOATING CONDITIONS MORE ACCEPTABLE BY MID-WEEK WITH SE WINDS 10
KNOTS OR LESS AND SEAS 2-3 FT NEARSHORE AND 3-4 FT OFFSHORE.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM...LASCODY
IMPACT WX....SEDLOCK/VOLKMER
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1014 AM EDT SAT AUG 29 2015
.SYNOPSIS...
A WEAK FRONTAL BOUNDARY WILL REMAIN STALLED JUST OFF TO THE SOUTH
OF THE FORECAST AREA...WITH DRY SURFACE HIGH PRESSURE REMAINING
ANCHORED OVER THE WESTERN AND CENTRAL CAROLINAS. INCREASING
ATMOSPHERIC MOISTURE WILL DRIFT SLOWLY NORTH INTO MAINLY SOUTHERN
AND WESTERN PORTIONS OF OUR REGION TODAY...AND INTO REMAINING
AREAS SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MAIN UPPER PATTERN CONTINUES TO BE DOMINATED BY THE WESTERN
ATLANTIC RIDGE...AND CUTOFF LOW IN THE NORTHERN GULF OF MEXICO.
ACROSS THE REGION...WEAK SURFACE TROUGH WILL REMAIN ACROSS THE
SOUTHERN PORTIONS OF THE CSRA...EXTENDING WESTWARD INTO CENTRAL
GA. THIS BOUNDARY MAY MOVE NORTHWARD SLIGHTLY THROUGHOUT THE
DAY...BUT DRIER AIR NORTH OF THIS FRONT WILL STILL DOMINATE MOST
OF THE CWA TODAY. MOST MODELS KEEP A DRY FORECAST ACROSS THE
CWA...WITH POSSIBLE SLIGHT CHANCE POPS ACROSS THE EXTREME SOUTHERN
CSRA WHERE MOISTURE RETURN MAY BE A LITTLE BETTER LATER THIS
AFTERNOON. LATEST HRRR DOES TRY TO BRING SHOWERS INTO THE EASTERN
CWA...BUT DUE TO THE AMOUNT OF DRY AIR CURRENTLY IN PLACE...HAVE
GONE WITH THE MODEL CONSENSUS AND KEPT THE THE MAJORITY OF THE
AREA DRY TODAY. SOME THIN HIGH CLOUDINESS WILL MOVE ACROSS THE
REGION...WHICH MAY HAVE A MINOR IMPACT ON AFTERNOON
HIGHS...KEEPING TEMPS VERY SIMILAR TO PREVIOUS DAYS READINGS. HAVE
GONE WITH HIGHS IN THE UPPER 80S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
THE UPPER LOW OVER THE NORTH-CENTRAL GULF WILL LIFT NORTHEASTWARD
TONIGHT INTO SUNDAY WITH MOISTURE EXPECTED TO CONTINUE TRENDING
NORTH. GFS MODEL PRECIPITABLE WATER VALUES INCREASE TO NEAR 2
INCHES FOR MOST ALL OF THE FA BY SUNDAY AFTERNOON. MODELS INDICATE
A POP GRADIENT WITH LOWER POPS NORTH/HIGHER POPS SOUTH. MODEL
GUIDANCE HAS BEEN TRENDING WETTER AND COOLER SO HAVE INCREASED
POPS AND ADJUSTED MAX TEMPS DOWN...IN THE MID TO UPPER 80S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
UPPER TROUGH TO REMAIN TO OUR WEST WITH UPPER RIDGE TO OUR EAST.
MAIN CONCERN WILL CONTINUE TO BE STATUS AND TRACK OF TROPICAL
CYCLONE ERIKA. OFFICIAL FORECASTS BRING THE SYSTEM INTO THE
EASTERN GULF OF MEXICO BY LATE SUN...AND NORTHWARD INTO N FL/S GA
VICINITY BY WED. EVEN WITHOUT THE CYCLONE IN PLAY...IT APPEARS
SUFFICIENT ATMOSPHERIC MOISTURE WOULD PROVIDE PREMISE FOR
SCATTERED DIURNAL CONVECTION OVER OUR FA ANYWAY. DUE TO
UNCERTAINTIES REGARDING POSSIBLE IMPACT OF ERIKA ON OUR
REGION...WILL CONTINUE TO MAINTAIN ONGOING FORECAST OF CHANCE
POPS...TRENDED A LITTLE HIGHER TO THE SOUTH. GENERALLY BLENDED
LATEST GUIDANCE WITH ONGOING FORECAST.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
MAINLY MID AND HIGH LEVEL CLOUDS ACROSS THE AREA LATE THIS
MORNING. DO NOT EXPECT ANY CONVECTION TO IMPACT TAF
SITES...MAINLY DUE TO THE BEST MOISTURE REMAINING SOUTH OF THE
SITES.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE IN MAINLY EARLY
MORNING FOG AND STRATUS PLUS AFTERNOON AND EVENING SCATTERED
THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
638 AM EDT SAT AUG 29 2015
.SYNOPSIS...
A WEAK FRONTAL BOUNDARY WILL REMAIN STALLED JUST OFF TO THE SOUTH
OF THE FORECAST AREA...WITH DRY SURFACE HIGH PRESSURE REMAINING
ANCHORED OVER THE WESTERN AND CENTRAL CAROLINAS. INCREASING
ATMOSPHERIC MOISTURE WILL DRIFT SLOWLY NORTH INTO MAINLY SOUTHERN
AND WESTERN PORTIONS OF OUR REGION TODAY...AND INTO REMAINING
AREAS SUNDAY.
&&
.NEAR TERM /TODAY/...
LITTLE CHANGE FROM PREVIOUS THINKING. MAIN UPPER PATTERN
CONTINUES TO BE DOMINATED BY THE WESTERN ATLANTIC RIDGE...AND
CUTOFF LOW IN THE NORTHERN GULF OF MEXICO. ACROSS THE
REGION...WEAK SURFACE TROUGH WILL REMAIN ACROSS THE SOUTHERN
PORTIONS OF THE CSRA...EXTENDING WESTWARD INTO CENTRAL GA. THIS
BOUNDARY MAY MOVE NORTHWARD SLIGHTLY THROUGHOUT THE DAY...BUT
DRIER AIR NORTH OF THIS FRONT WILL STILL DOMINATE MOST OF THE CWA
TODAY. MOST MODELS KEEP A DRY FORECAST ACROSS THE CWA...WITH
POSSIBLE SLIGHT CHANCE POPS ACROSS THE EXTREME SOUTHERN CSRA WHERE
MOISTURE RETURN MAY BE A LITTLE BETTER LATER THIS AFTERNOON.
LATEST HRRR DOES TRY TO BRING SHOWERS INTO THE EASTERN CWA...BUT
DUE TO THE AMOUNT OF DRY AIR CURRENTLY IN PLACE...HAVE GONE WITH
THE MODEL CONSENSUS AND KEPT THE THE MAJORITY OF THE AREA DRY
TODAY. SOME THIN HIGH CLOUDINESS WILL MOVE ACROSS THE REGION...WHICH
MAY HAVE A MINOR IMPACT ON AFTERNOON HIGHS...KEEPING TEMPS VERY
SIMILAR TO PREVIOUS DAYS READINGS. HAVE GONE WITH HIGHS IN THE
UPPER 80S.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
THE UPPER LOW OVER THE NORTH-CENTRAL GULF WILL LIFT NORTHEASTWARD
TONIGHT INTO SUNDAY WITH MOISTURE EXPECTED TO CONTINUE TRENDING
NORTH. GFS MODEL PRECIPITABLE WATER VALUES INCREASE TO NEAR 2
INCHES FOR MOST ALL OF THE FA BY SUNDAY AFTERNOON. MODELS INDICATE
A POP GRADIENT WITH LOWER POPS NORTH/HIGHER POPS SOUTH. MODEL
GUIDANCE HAS BEEN TRENDING WETTER AND COOLER SO HAVE INCREASED
POPS AND ADJUSTED MAX TEMPS DOWN...IN THE MID TO UPPER 80S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
UPPER TROUGH TO REMAIN TO OUR WEST WITH UPPER RIDGE TO OUR EAST.
MAIN CONCERN WILL CONTINUE TO BE STATUS AND TRACK OF TROPICAL
CYCLONE ERIKA. OFFICIAL FORECASTS BRING THE SYSTEM INTO THE
EASTERN GULF OF MEXICO BY LATE SUN...AND NORTHWARD INTO N FL/S GA
VICINITY BY WED. EVEN WITHOUT THE CYCLONE IN PLAY...IT APPEARS
SUFFICIENT ATMOSPHERIC MOISTURE WOULD PROVIDE PREMISE FOR
SCATTERED DIURNAL CONVECTION OVER OUR FA ANYWAY. DUE TO
UNCERTAINTIES REGARDING POSSIBLE IMPACT OF ERIKA ON OUR
REGION...WILL CONTINUE TO MAINTAIN ONGOING FORECAST OF CHANCE
POPS...TRENDED A LITTLE HIGHER TO THE SOUTH. GENERALLY BLENDED
LATEST GUIDANCE WITH ONGOING FORECAST.
&&
.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
HIGHER MOISTURE ACROSS THE CSRA TAF SITES BEING SHOWN BY HIGHER
DEWPOINTS THERE. MIDLANDS SITES...AND AREAS FURTHER NORTH...ARE
SHOWING SLIGHTLY DRIER AIR. MODELS CONTINUE TO SHOW VFR CONDITIONS
EARLY THIS MORNING AND THROUGH THE DAY. WITH HIGHER MOISTURE
ACROSS AGS...CAN NOT RULE OUT A DROP INTO MVFR VISIBILITIES
BRIEFLY THROUGH SUNRISE. THIN CIRRUS MOVING INTO THE REGION SHOULD
ALSO HELP LIMIT ANY WIDESPREAD FOG/STRATUS FORMATION THIS MORNING.
DO NOT EXPECT ANY CONVECTION TO IMPACT TAF SITES...MAINLY DUE TO
THE BEST MOISTURE REMAINING SOUTH OF THE SITES.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE IN MAINLY EARLY
MORNING FOG AND STRATUS PLUS AFTERNOON AND EVENING SCATTERED
THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
99
AREA FORECAST DISCUSSION
NWS LINCOLN IL
228 PM CDT SAT AUG 29 2015
.SHORT TERM...(TONIGHT)
ISSUED AT 228 PM CDT SAT AUG 29 2015
LATEST SURFACE MAP SHOWING FRONTAL BOUNDARY ARCING FROM THE
NORTHEAST TIP OF ILLINOIS TO EAST CENTRAL IOWA...BEFORE EXTENDING
SOUTHWEST INTO SOUTHEAST KANSAS. PRECIPITATION HAS LARGELY REMAINED
LIGHT AND SCATTERED...AND HAS BEEN MOSTLY EAST OF I-55 THE LAST
SEVERAL HOURS. DECENT SLUG OF DRY AIR ALOFT SEEN ON WATER VAPOR
IMAGERY SOUTH OF A SHORTWAVE...WHICH IS CURRENTLY DROPPING INTO
SOUTHERN IOWA. SHORT-RANGE MODEL GUIDANCE IS HAVING A BIT OF
DIFFICULTY AS TO THE AMOUNT OF REDEVELOPMENT...BUT THE HRRR IS
PERFORMING HALFWAY DECENTLY AND CONTINUES TO SUGGEST MAINLY SCATTERED
SHOWERS. THUNDER HAS BEEN STAYING AWAY FROM OUR AREA SO FAR...AND
WHILE MESOANALYSIS SHOWS RESPECTABLE CAPE VALUES OF 1000-1500 J/KG
THIS AFTERNOON...MID LEVEL LAPSE RATES ARE FAIRLY MODEST. THEREFORE
WILL CONTINUE MENTION WITH ONLY ISOLATED THUNDERSTORMS THROUGH
TONIGHT...WITH THE THREAT DIMINISHING FROM NORTHWEST TO SOUTHEAST.
SOME CONCERNS LATER IN THE NIGHT WITH POTENTIAL FOR SOME FOG...
MAINLY ACROSS THE NORTHWEST CWA. STILL QUITE A BIT OF LOWER
STRATOCUMULUS ACROSS MOST OF IOWA AND WISCONSIN. LATEST RAP MODEL
GUIDANCE SUGGESTS THIS CONTRACTING SOME MORE OVER THE NEXT SEVERAL
HOURS...BEFORE SIGNIFICANTLY EXPANDING AGAIN THIS EVENING WITH HIGH
PRESSURE EXPANDING OVER THE MIDWEST. MUCH OF THE AREA UNDERNEATH
THIS HIGH SAW FROM 1 TO SEVERAL INCHES OF RAIN IN THE LAST COUPLE
DAYS...AND IS MOST FAVORED FOR DENSE FOG POTENTIAL. HOWEVER...THE
RAP SHOWS THE FOG FIELD OOZING SOUTHWARD AFTER MIDNIGHT...PERHAPS AS
FAR AS PEORIA. THAT AREA ALREADY HAD PATCHY FOG IN THE GRIDS...BUT
AM THINKING IT WILL BE A BIT MORE WIDESPREAD AND WILL GO WITH AREAS
OF FOG INSTEAD.
&&
.LONG TERM...(SUNDAY THROUGH SATURDAY)
ISSUED AT 228 PM CDT SAT AUG 29 2015
SHOWERS AND ISOLATED THUNDERSTORMS COULD LINGER IN THE SOUTHEASTERN
PART OF THE CWA SUNDAY MORNING BUT THEN SPREAD BACK WEST
SOME...COVERING THE EASTERN HALF OF THE CWA...MAINLY EAST OF I-55.
THIS SHOULD BE THE END OF THE PCPN AS THE FRONTAL SYSTEM DIMINISHES
OVER THE AREA REMAINDER OF THE WEEKEND. FOG AND LOWER CLOUDS WILL
SEEN THIS MORNING ALONG AND BEHIND THE FRONT...SO THINKING IS THAT
THE FOG WILL CONTINUE INTO THE FIRST FEW HOURS OF SUNDAY MORNING.
HAVE INCLUDED A SLIGHT CHANCE OF SHOWERS FOR SUNDAY NIGHT...AGAIN
MAINLY EAST OF I-55 TIL MIDNIGHT...AND THEN IN THE EXTREME SOUTHEAST
AFTER MIDNIGHT.
BEYOND THIS UPPER LEVEL RIDGING WILL BUILD INTO THE NORTHERN PLAINS
AND NORTHERN MISS VALLEY. ON THE SFC...HIGH PRESSURE RIDGING WILL
BUILD BACK TOWARD THE AREA FROM THE SOUTHEAST. THE COMBINATION OF
THE TWO SHOULD HELP TO KEEP THE AREA DRY THROUGH THE BEGINNING OF
THE WEEK. TEMPS WILL BE IN THE LOWER TO MIDDLE 80S TOMORROW...BUT
THEN WARM INTO THE MIDDLE TO UPPER 80S FOR MONDAY INTO TUESDAY.
THE REMAINDER OF THE WEEK LOOKS TO BE DRY...THOUGH SOME OF THE
MODELS CONTINUE TO BRING SOME SPOTTY POPS IN THE AREA DUE TO
SOUTHERLY FLOW ON THE SFC. FOR NOW...WILL ONLY HAVE SLIGHT CHC POPS
FOR WED ACROSS AREAS ALONG AND NORTH OF I-74 AND EAST OF I-57.
REMAINDER OF THE WEEK WITH BE DRY...EVEN INTO THE BEGINNING OF THE
LABOR DAY WEEKEND. TEMPS WILL REMAIN WELL ABOVE NORMAL IN THE
EXTENDED PERIOD SO HEAT COULD BE AN ISSUE LATER...BUT DEWPOINTS WILL
REMAIN LOW SO HEAT INDEX VALUES ARE NOT EXPECTED TO GET OVER 100
THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1230 PM CDT SAT AUG 29 2015
MAINLY VFR CONDITIONS OVER CENTRAL ILLINOIS AT MIDDAY...WITH A FEW
SHOWERS EAST OF KBMI-KSPI. WATCHING AN AREA OF MVFR/IFR CEILINGS
DROPPING DOWN FROM IOWA AND NORTHWEST ILLINOIS AHEAD OF AN UPPER
LEVEL DISTURBANCE...AND MVFR CEILINGS ARE NOT TOO FAR AWAY FROM
KPIA. SOME QUESTION AS TO THE SOUTHWARD PROGRESS...WITH THE RAP
MODEL KEEPING KPIA JUST ABOVE VFR LEVEL AND THE NAM DIPPING INTO
MVFR TERRITORY. HAVE INCLUDED SOME TEMPO CEILINGS AROUND 2500 FEET
THERE INITIALLY AND WILL CONTINUE TO EVALUATE THE PROGRESSION OVER
THE NEXT HOUR OR SO. MORE OF THE CONCERN FOR MVFR CONDITIONS OVER
CENTRAL ILLINOIS WILL BE AFTER 06Z...AS A WEAKENING FRONTAL
BOUNDARY BECOMES NEARLY STATIONARY OVERHEAD. THE WIDESPREAD LOW
CLOUDS CURRENTLY TO OUR NORTHWEST ARE NOT LIKELY TO COMPLETELY
ERODE AND MORE LIKELY WOULD EXPAND OVERNIGHT...WITH THE RAP
HINTING AT POTENTIAL IFR/LIFR CONDITIONS AT KPIA LATE IN THE
NIGHT. HAVE HIT CONDITIONS AT KPIA THE HARDEST WITH TEMPO CEILINGS
AND VISIBILITIES THAT LOW...BUT MAINTAINED MVFR CONDITIONS
ELSEWHERE LATE TONIGHT INTO SUNDAY MORNING.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GEELHART
LONG TERM...AUTEN
AVIATION...GEELHART
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1230 PM CDT SAT AUG 29 2015
.UPDATE...
ISSUED AT 1018 AM CDT SAT AUG 29 2015
SCATTERED SHOWERS CONTINUE TO PUSH ACROSS AREAS MAINLY EAST OF
I-55 THIS MORNING...WITH SOME SPRINKLES STARTING TO MOVE INTO
PARTS OF SOUTHEAST ILLINOIS AS WELL. MORNING SOUNDING FROM OUR
OFFICE SHOWED QUITE A BIT OF DRY AIR BELOW 12000 FEET...WHICH HAS
HELPED KEEP MOST OF THE RAIN LIMITED TO A FEW HUNDREDTHS OF
ACCUMULATION. LATEST RAP MODEL SOUNDINGS SHOW SOME MOISTENING OF
THE COLUMN DOWN TO ABOUT 5000 FEET OVER THE NEXT FEW HOURS...
HOWEVER SOME DRIER AIR IS ALSO EVIDENT ON WATER VAPOR IMAGERY
DROPPING SOUTHWARD AHEAD OF A FAST MOVING SHORTWAVE NOW LOCATED IN
NORTHERN IOWA...WHICH SHOULD KEEP THE NORTHWEST PART OF THE
FORECAST AREA DRY FOR A COUPLE MORE HOURS. HIGHER RESOLUTION MODEL
GUIDANCE SUGGESTS SOME ADDITIONAL SHOWERS SURGING NORTHEAST OUT OF
SOUTHERN MISSOURI AS A WEAK FRONTAL BOUNDARY PUSHES EAST. EARLIER
GRID UPDATES HAD INTRODUCED THIS TREND AND ONLY REQUIRED MINOR
UPDATES...MAINLY TO NUDGE TEMPERATURES DOWN A BIT.
&&
.SHORT TERM...(TODAY)
ISSUED AT 312 AM CDT SAT AUG 29 2015
07Z/2AM SURFACE ANALYSIS SHOWS A WEAK FRONTAL BOUNDARY EXTENDING
FROM WISCONSIN SOUTHWESTWARD TO THE TEXAS PANHANDLE. A PLUME OF
MAINLY MID-LEVEL MOISTURE AHEAD OF THE FRONT HAS RESULTED IN
SCATTERED LIGHT SHOWERS/SPRINKLES ACROSS THE WESTERN HALF OF THE
KILX CWA EARLY THIS MORNING. 00Z UPPER AIR SOUNDING SHOWED PLENTY
OF DRY AIR BELOW 850MB...SO PRECIP HAS BEEN HAVING A HARD TIME
REACHING THE GROUND IN MANY AREAS. FORECAST SOUNDINGS SHOW A
GRADUAL MOISTENING OF THE PROFILE TODAY...HOWEVER DEEP-LAYER
MOISTURE REMAINS LACKING. IN ADDITION...WIDESPREAD CLOUD COVER WILL
LIMIT INSTABILITY...WITH GFS SBCAPE VALUES ONLY REACHING THE 500 TO
1000J/KG RANGE. END RESULT WILL BE SCATTERED SHOWERS WITH PERHAPS A
RUMBLE OF THUNDER. THINK AREAL COVERAGE OF PRECIP WILL REMAIN
LOW...SO WILL ONLY CARRY 30-40 POPS. HIGH TEMPERATURES WILL RANGE
FROM THE UPPER 70S ALONG/NORTHWEST OF THE ILLINOIS RIVER...TO THE
MIDDLE 80S ALONG/SOUTHEAST OF I-70 WHERE CONDITIONS WILL REMAIN DRY
UNTIL A FEW SHOWERS ARRIVE DURING THE AFTERNOON.
.LONG TERM...(TONIGHT THROUGH FRIDAY)
ISSUED AT 312 AM CDT SAT AUG 29 2015
FRONTAL BOUNDARY WILL SLOWLY PUSH EASTWARD LATER TODAY INTO
TONIGHT...WITH MODEL CONSENSUS SHOWING IT REACHING A CHICAGO TO
KIRKSVILLE LINE BY 12Z SUN. SCATTERED SHOWERS WILL BE ONGOING
AHEAD OF THE FRONT ACROSS MUCH OF THE AREA THIS EVENING...THEN
WILL SHIFT TO MAINLY LOCATIONS ALONG/EAST OF I-57 OVERNIGHT. MAIN
WEATHER CONCERN FOR TONIGHT WILL BE THE POTENTIAL FOR FOG ACROSS
THE W/NW CWA. AS THE SLOW-MOVING FRONT ARRIVES...WINDS WILL BECOME
LIGHT/VARIABLE ACROSS THIS AREA. DUE TO THE NEARLY CALM
WINDS...ADDED LOW-LEVEL MOISTURE FROM SHOWERS TODAY...AND PARTIAL
CLEARING LATE TONIGHT...THINK AT LEAST PATCHY FOG WILL FORM. BOTH
FORECAST SOUNDINGS AND NUMERIC GUIDANCE SUGGEST A REDUCTION IN
VSBY OVERNIGHT. CURRENT OBSERVATIONS IN THE VICINITY OF THE FRONT
ACROSS IOWA SHOW WIDESPREAD FOG...WITH A FEW VSBYS DOWN TO AROUND
1/4 MILE. THINK THIS SAME SCENARIO WILL UNFOLD FURTHER EAST
TONIGHT...SO HAVE INCLUDED PATCHY FOG IN THE FORECAST WEST OF I-55
AFTER MIDNIGHT.
THE FRONTAL BOUNDARY WILL SLOWLY DISSIPATE ON SUNDAY...HOWEVER
ENOUGH UPPER-LEVEL SUPPORT WILL PERSIST TO SUPPORT AT LEAST A
MENTION OF A FEW SHOWERS/THUNDERSTORMS. MOST MODELS PRODUCE LIGHT
QPF ACROSS NEARLY THE ENTIRE CWA AS THE BOUNDARY HAS SLOWED SLIGHTLY
FROM PREVIOUS RUNS. AS A RESULT...HAVE PULLED POPS FURTHER WEST TO
INCLUDE SLIGHT CHANCES AS FAR WEST AS THE ILLINOIS RIVER SUNDAY
AFTERNOON/EVENING.
AFTER THAT...THE REMAINDER OF THE EXTENDED LOOKS WARM AND DRY AS
UPPER-LEVEL RIDGING DOMINATES THE EASTERN CONUS THROUGH THE END OF
THE COMING WEEK. A SLIGHT WEAKNESS IN THE RIDGE APPEARS TO DEVELOP
ACROSS ILLINOIS INTO THE OHIO RIVER VALLEY...POTENTIALLY TRIGGERING
ISOLATED AFTERNOON/EVENING CONVECTION TUESDAY THROUGH FRIDAY.
HOWEVER...MID-LEVEL WARMING BENEATH THE RIDGE WILL LIKELY LEAD TO
CAPPING AND AN OVERALL SUPPRESSION OF CONVECTION. AS A
RESULT...WILL MAINTAIN A DRY FORECAST WITH HIGH TEMPERATURES
CLIMBING INTO THE UPPER 80S TO AROUND 90 DEGREES EACH DAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1230 PM CDT SAT AUG 29 2015
MAINLY VFR CONDITIONS OVER CENTRAL ILLINOIS AT MIDDAY...WITH A FEW
SHOWERS EAST OF KBMI-KSPI. WATCHING AN AREA OF MVFR/IFR CEILINGS
DROPPING DOWN FROM IOWA AND NORTHWEST ILLINOIS AHEAD OF AN UPPER
LEVEL DISTURBANCE...AND MVFR CEILINGS ARE NOT TOO FAR AWAY FROM
KPIA. SOME QUESTION AS TO THE SOUTHWARD PROGRESS...WITH THE RAP
MODEL KEEPING KPIA JUST ABOVE VFR LEVEL AND THE NAM DIPPING INTO
MVFR TERRITORY. HAVE INCLUDED SOME TEMPO CEILINGS AROUND 2500 FEET
THERE INITIALLY AND WILL CONTINUE TO EVALUATE THE PROGRESSION OVER
THE NEXT HOUR OR SO. MORE OF THE CONCERN FOR MVFR CONDITIONS OVER
CENTRAL ILLINOIS WILL BE AFTER 06Z...AS A WEAKENING FRONTAL
BOUNDARY BECOMES NEARLY STATIONARY OVERHEAD. THE WIDESPREAD LOW
CLOUDS CURRENTLY TO OUR NORTHWEST ARE NOT LIKELY TO COMPLETELY
ERODE AND MORE LIKELY WOULD EXPAND OVERNIGHT...WITH THE RAP
HINTING AT POTENTIAL IFR/LIFR CONDITIONS AT KPIA LATE IN THE
NIGHT. HAVE HIT CONDITIONS AT KPIA THE HARDEST WITH TEMPO CEILINGS
AND VISIBILITIES THAT LOW...BUT MAINTAINED MVFR CONDITIONS
ELSEWHERE LATE TONIGHT INTO SUNDAY MORNING.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEELHART
SHORT TERM...BARNES
LONG TERM...BARNES
AVIATION...GEELHART
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1019 AM CDT SAT AUG 29 2015
.UPDATE...
ISSUED AT 1018 AM CDT SAT AUG 29 2015
SCATTERED SHOWERS CONTINUE TO PUSH ACROSS AREAS MAINLY EAST OF
I-55 THIS MORNING...WITH SOME SPRINKLES STARTING TO MOVE INTO
PARTS OF SOUTHEAST ILLINOIS AS WELL. MORNING SOUNDING FROM OUR
OFFICE SHOWED QUITE A BIT OF DRY AIR BELOW 12000 FEET...WHICH HAS
HELPED KEEP MOST OF THE RAIN LIMITED TO A FEW HUNDREDTHS OF
ACCUMULATION. LATEST RAP MODEL SOUNDINGS SHOW SOME MOISTENING OF
THE COLUMN DOWN TO ABOUT 5000 FEET OVER THE NEXT FEW HOURS...
HOWEVER SOME DRIER AIR IS ALSO EVIDENT ON WATER VAPOR IMAGERY
DROPPING SOUTHWARD AHEAD OF A FAST MOVING SHORTWAVE NOW LOCATED IN
NORTHERN IOWA...WHICH SHOULD KEEP THE NORTHWEST PART OF THE
FORECAST AREA DRY FOR A COUPLE MORE HOURS. HIGHER RESOLUTION MODEL
GUIDANCE SUGGESTS SOME ADDITIONAL SHOWERS SURGING NORTHEAST OUT OF
SOUTHERN MISSOURI AS A WEAK FRONTAL BOUNDARY PUSHES EAST. EARLIER
GRID UPDATES HAD INTRODUCED THIS TREND AND ONLY REQUIRED MINOR
UPDATES...MAINLY TO NUDGE TEMPERATURES DOWN A BIT.
&&
.SHORT TERM...(TODAY)
ISSUED AT 312 AM CDT SAT AUG 29 2015
07Z/2AM SURFACE ANALYSIS SHOWS A WEAK FRONTAL BOUNDARY EXTENDING
FROM WISCONSIN SOUTHWESTWARD TO THE TEXAS PANHANDLE. A PLUME OF
MAINLY MID-LEVEL MOISTURE AHEAD OF THE FRONT HAS RESULTED IN
SCATTERED LIGHT SHOWERS/SPRINKLES ACROSS THE WESTERN HALF OF THE
KILX CWA EARLY THIS MORNING. 00Z UPPER AIR SOUNDING SHOWED PLENTY
OF DRY AIR BELOW 850MB...SO PRECIP HAS BEEN HAVING A HARD TIME
REACHING THE GROUND IN MANY AREAS. FORECAST SOUNDINGS SHOW A
GRADUAL MOISTENING OF THE PROFILE TODAY...HOWEVER DEEP-LAYER
MOISTURE REMAINS LACKING. IN ADDITION...WIDESPREAD CLOUD COVER WILL
LIMIT INSTABILITY...WITH GFS SBCAPE VALUES ONLY REACHING THE 500 TO
1000J/KG RANGE. END RESULT WILL BE SCATTERED SHOWERS WITH PERHAPS A
RUMBLE OF THUNDER. THINK AREAL COVERAGE OF PRECIP WILL REMAIN
LOW...SO WILL ONLY CARRY 30-40 POPS. HIGH TEMPERATURES WILL RANGE
FROM THE UPPER 70S ALONG/NORTHWEST OF THE ILLINOIS RIVER...TO THE
MIDDLE 80S ALONG/SOUTHEAST OF I-70 WHERE CONDITIONS WILL REMAIN DRY
UNTIL A FEW SHOWERS ARRIVE DURING THE AFTERNOON.
.LONG TERM...(TONIGHT THROUGH FRIDAY)
ISSUED AT 312 AM CDT SAT AUG 29 2015
FRONTAL BOUNDARY WILL SLOWLY PUSH EASTWARD LATER TODAY INTO
TONIGHT...WITH MODEL CONSENSUS SHOWING IT REACHING A CHICAGO TO
KIRKSVILLE LINE BY 12Z SUN. SCATTERED SHOWERS WILL BE ONGOING
AHEAD OF THE FRONT ACROSS MUCH OF THE AREA THIS EVENING...THEN
WILL SHIFT TO MAINLY LOCATIONS ALONG/EAST OF I-57 OVERNIGHT. MAIN
WEATHER CONCERN FOR TONIGHT WILL BE THE POTENTIAL FOR FOG ACROSS
THE W/NW CWA. AS THE SLOW-MOVING FRONT ARRIVES...WINDS WILL BECOME
LIGHT/VARIABLE ACROSS THIS AREA. DUE TO THE NEARLY CALM
WINDS...ADDED LOW-LEVEL MOISTURE FROM SHOWERS TODAY...AND PARTIAL
CLEARING LATE TONIGHT...THINK AT LEAST PATCHY FOG WILL FORM. BOTH
FORECAST SOUNDINGS AND NUMERIC GUIDANCE SUGGEST A REDUCTION IN
VSBY OVERNIGHT. CURRENT OBSERVATIONS IN THE VICINITY OF THE FRONT
ACROSS IOWA SHOW WIDESPREAD FOG...WITH A FEW VSBYS DOWN TO AROUND
1/4 MILE. THINK THIS SAME SCENARIO WILL UNFOLD FURTHER EAST
TONIGHT...SO HAVE INCLUDED PATCHY FOG IN THE FORECAST WEST OF I-55
AFTER MIDNIGHT.
THE FRONTAL BOUNDARY WILL SLOWLY DISSIPATE ON SUNDAY...HOWEVER
ENOUGH UPPER-LEVEL SUPPORT WILL PERSIST TO SUPPORT AT LEAST A
MENTION OF A FEW SHOWERS/THUNDERSTORMS. MOST MODELS PRODUCE LIGHT
QPF ACROSS NEARLY THE ENTIRE CWA AS THE BOUNDARY HAS SLOWED SLIGHTLY
FROM PREVIOUS RUNS. AS A RESULT...HAVE PULLED POPS FURTHER WEST TO
INCLUDE SLIGHT CHANCES AS FAR WEST AS THE ILLINOIS RIVER SUNDAY
AFTERNOON/EVENING.
AFTER THAT...THE REMAINDER OF THE EXTENDED LOOKS WARM AND DRY AS
UPPER-LEVEL RIDGING DOMINATES THE EASTERN CONUS THROUGH THE END OF
THE COMING WEEK. A SLIGHT WEAKNESS IN THE RIDGE APPEARS TO DEVELOP
ACROSS ILLINOIS INTO THE OHIO RIVER VALLEY...POTENTIALLY TRIGGERING
ISOLATED AFTERNOON/EVENING CONVECTION TUESDAY THROUGH FRIDAY.
HOWEVER...MID-LEVEL WARMING BENEATH THE RIDGE WILL LIKELY LEAD TO
CAPPING AND AN OVERALL SUPPRESSION OF CONVECTION. AS A
RESULT...WILL MAINTAIN A DRY FORECAST WITH HIGH TEMPERATURES
CLIMBING INTO THE UPPER 80S TO AROUND 90 DEGREES EACH DAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 635 AM CDT SAT AUG 29 2015
GENERALLY QUIET/VFR CONDITIONS EXPECTED ACROSS THE CENTRAL
ILLINOIS TERMINALS THROUGH THE 12Z TAF VALID TIME, DESPITE THE
PRESENCE OF A WEAK WEATHER DISTURBANCE AND SPOTTY
SHOWERS/THUNDERSTORMS. AT THIS POINT, EXPECT THE THUNDER COVERAGE
TO BE TOO SPARSE TO WARRANT A MENTION, AND WILL LIMIT SHOWERS TO
VCSH. THE ADDED LOW LEVEL MOISTURE FROM THE PRECIPITATION IN THE
AREA, AS WELL AS THE SLOW APPROACH OF A FRONTAL BOUNDARY
ASSOCIATED WITH DISTURBANCE, MAY RESULT IN FOG AND/OR STRATUS
DEVELOPMENT BY LATE TONIGHT. KPIA STANDS THE BEST CHANCE OF SEEING
A SIGNIFICANT CIG/VSBY REDUCTION LATER TONIGHT AS THE FRONTAL
BOUNDARY SHOULD BE CLOSEST TO THAT TERMINAL.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEELHART
SHORT TERM...BARNES
LONG TERM...BARNES
AVIATION...BAK
AREA FORECAST DISCUSSION
NWS LINCOLN IL
312 AM CDT SAT AUG 29 2015
.SHORT TERM...(TODAY)
ISSUED AT 312 AM CDT SAT AUG 29 2015
07Z/2AM SURFACE ANALYSIS SHOWS A WEAK FRONTAL BOUNDARY EXTENDING
FROM WISCONSIN SOUTHWESTWARD TO THE TEXAS PANHANDLE. A PLUME OF
MAINLY MID-LEVEL MOISTURE AHEAD OF THE FRONT HAS RESULTED IN
SCATTERED LIGHT SHOWERS/SPRINKLES ACROSS THE WESTERN HALF OF THE
KILX CWA EARLY THIS MORNING. 00Z UPPER AIR SOUNDING SHOWED PLENTY
OF DRY AIR BELOW 850MB...SO PRECIP HAS BEEN HAVING A HARD TIME
REACHING THE GROUND IN MANY AREAS. FORECAST SOUNDINGS SHOW A
GRADUAL MOISTENING OF THE PROFILE TODAY...HOWEVER DEEP-LAYER
MOISTURE REMAINS LACKING. IN ADDITION...WIDESPREAD CLOUD COVER WILL
LIMIT INSTABILITY...WITH GFS SBCAPE VALUES ONLY REACHING THE 500 TO
1000J/KG RANGE. END RESULT WILL BE SCATTERED SHOWERS WITH PERHAPS A
RUMBLE OF THUNDER. THINK AREAL COVERAGE OF PRECIP WILL REMAIN
LOW...SO WILL ONLY CARRY 30-40 POPS. HIGH TEMPERATURES WILL RANGE
FROM THE UPPER 70S ALONG/NORTHWEST OF THE ILLINOIS RIVER...TO THE
MIDDLE 80S ALONG/SOUTHEAST OF I-70 WHERE CONDITIONS WILL REMAIN DRY
UNTIL A FEW SHOWERS ARRIVE DURING THE AFTERNOON.
&&
.LONG TERM...(TONIGHT THROUGH FRIDAY)
ISSUED AT 312 AM CDT SAT AUG 29 2015
FRONTAL BOUNDARY WILL SLOWLY PUSH EASTWARD LATER TODAY INTO
TONIGHT...WITH MODEL CONSENSUS SHOWING IT REACHING A CHICAGO TO
KIRKSVILLE LINE BY 12Z SUN. SCATTERED SHOWERS WILL BE ONGOING
AHEAD OF THE FRONT ACROSS MUCH OF THE AREA THIS EVENING...THEN
WILL SHIFT TO MAINLY LOCATIONS ALONG/EAST OF I-57 OVERNIGHT. MAIN
WEATHER CONCERN FOR TONIGHT WILL BE THE POTENTIAL FOR FOG ACROSS
THE W/NW CWA. AS THE SLOW-MOVING FRONT ARRIVES...WINDS WILL BECOME
LIGHT/VARIABLE ACROSS THIS AREA. DUE TO THE NEARLY CALM
WINDS...ADDED LOW-LEVEL MOISTURE FROM SHOWERS TODAY...AND PARTIAL
CLEARING LATE TONIGHT...THINK AT LEAST PATCHY FOG WILL FORM. BOTH
FORECAST SOUNDINGS AND NUMERIC GUIDANCE SUGGEST A REDUCTION IN
VISBY OVERNIGHT. CURRENT OBSERVATIONS IN THE VICINITY OF THE FRONT
ACROSS IOWA SHOW WIDESPREAD FOG...WITH A FEW VISBYS DOWN TO AROUND
1/4 MILE. THINK THIS SAME SCENARIO WILL UNFOLD FURTHER EAST
TONIGHT...SO HAVE INCLUDED PATCHY FOG IN THE FORECAST WEST OF I-55
AFTER MIDNIGHT.
THE FRONTAL BOUNDARY WILL SLOWLY DISSIPATE ON SUNDAY...HOWEVER
ENOUGH UPPER-LEVEL SUPPORT WILL PERSIST TO SUPPORT AT LEAST A
MENTION OF A FEW SHOWERS/THUNDERSTORMS. MOST MODELS PRODUCE LIGHT
QPF ACROSS NEARLY THE ENTIRE CWA AS THE BOUNDARY HAS SLOWED SLIGHTLY
FROM PREVIOUS RUNS. AS A RESULT...HAVE PULLED POPS FURTHER WEST TO
INCLUDE SLIGHT CHANCES AS FAR WEST AS THE ILLINOIS RIVER SUNDAY
AFTERNOON/EVENING.
AFTER THAT...THE REMAINDER OF THE EXTENDED LOOKS WARM AND DRY AS
UPPER-LEVEL RIDGING DOMINATES THE EASTERN CONUS THROUGH THE END OF
THE COMING WEEK. A SLIGHT WEAKNESS IN THE RIDGE APPEARS TO DEVELOP
ACROSS ILLINOIS INTO THE OHIO RIVER VALLEY...POTENTIALLY TRIGGERING
ISOLATED AFTERNOON/EVENING CONVECTION TUESDAY THROUGH FRIDAY.
HOWEVER...MID-LEVEL WARMING BENEATH THE RIDGE WILL LIKELY LEAD TO
CAPPING AND AN OVERALL SUPPRESSION OF CONVECTION. AS A
RESULT...WILL MAINTAIN A DRY FORECAST WITH HIGH TEMPERATURES
CLIMBING INTO THE UPPER 80S TO AROUND 90 DEGREES EACH DAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1142 PM CDT FRI AUG 28 2015
LOW PRESSURE CENTERED IN WESTERN IOWA WILL CONTINUE TO DRIFT EAST
TONIGHT. IT WILL GRADUALLY DISSIPATE NEAR WESTERN ILLINOIS
SATURDAY AFTERNOON/EVE. SHOWERS HAVE EXPANDED IN COVERAGE BETWEEN
04Z-05Z, AND RAIN IS STARTING TO REACH THE GROUND FROM CLOUD
BASES AT 8K FT OR HIGHER. SCATTERED RAIN SHOWERS WILL PERIODICALLY
AFFECT THE TERMINAL SITES OVER THE NEXT 18 HOURS, BEFORE
DISSIPATING SATURDAY EVENING. THE CHANCES ONLY WARRANTED A VCSH
AND VFR CLOUD COVER, BASED ON FORECAST SOUNDINGS FROM HRRR AND
RAP/NAM OUTPUT. USED ONLY VCSH IN ALL TAFS TO ACCOUNT FOR PRECIP,
AS TIMING WILL BE HIGHLY VARIABLE IN TERMS OF TIMING AND LOCATION.
ENDED ALL MENTION OF PRECIP BEFORE 00Z/30. WINDS ARE EXPECTED TO
REMAIN SOUTH THROUGH AT LEAST 18Z, THEN BEGIN TO SHIFT TO THE
SOUTHWEST AS THE LOW AND COLD FRONT APPROACH WESTERN ILLINOIS.
PREVAILING WIND SPEEDS SHOULD REMAIN 10KT OR LESS THROUGH TOMORROW
AFTERNOON.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BARNES
LONG TERM...BARNES
AVIATION...SHIMON
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
207 AM CDT SAT AUG 29 2015
.UPDATE...
626 PM CDT
HAVE ADJUSTED POPS DOWNWARD THROUGH THE MID EVENING HOURS TO
ACCOUNT FOR RADAR AND NEAR-TERM GUIDANCE TRENDS. LEADING EDGE OF
SHORTWAVE TROUGH AND VORTICITY MAXIMA WILL MOVE EAST FROM
WISCONSIN THIS EVENING...KEEPING BEST FORCING FOR PRECIP NORTH OF
THE STATE LINE. THUS...JUST HAVE GENERALLY ISOLATED
SHRA/INTERMITTENT SPRINKLE MENTION THROUGH MID EVENING IN FAR
NORTHERN ILLINOIS. VERY DRY AIR NOTED AROUND 800 MB ON A RECENT
AMDAR SOUNDING FROM MDW WILL MAKE IT TOUGH FOR ANY STEADY PRECIP
UNTIL DRY AIR GETS ERODED. UPPER TROUGH/SHORTWAVE AXIS AND
SHEARED VORT MAX ALONG TROUGH AXIS WILL SLOWLY PROGRESS FROM IA TO
NORTHERN IL LATE THIS EVENING AND OVERNIGHT...BRINGING GRADUALLY
INCREASING SHRA/RAIN COVERAGE FROM NORTHWEST TO SOUTHEAST...BUT
MANY AREAS ALONG AND EAST OF AN EVANSTON TO PONTIAC LINE COULD
VERY WELL REMAIN DRY THROUGH DAYBREAK. VERY LITTLE IF ANY
INSTABILITY OVER AREA THROUGH THE NIGHT AND POOR MIDLEVEL LAPSE
RATES SUPPORT KEEPING SLIGHT CHANCE TSRA AT BEST. THE REST OF THE
FORECAST LOOKS TO BE ON TRACK.
RC
&&
.SHORT TERM...
TONIGHT AND SATURDAY...
250 PM...FORECAST CONCERNS INCLUDE PRECIP COVERAGE/TIMING AND
RAINFALL AMOUNTS.
LOW PRESSURE OVER WESTERN IOWA WILL SLOWLY MOVE EAST TONIGHT AND
EVENTUALLY DISSIPATE OVER NORTHERN ILLINOIS SATURDAY. FIRST WAVE OF
PRECIP IS GENERALLY LIFTING NORTHEAST INTO SOUTHERN WISCONSIN AND
THE MODELS SEEM TO HAVE THIS HANDLED FAIRLY WELL WITH THE HRRR ALSO
SHOWING JUST ISOLATED SHOWERS/SPRINKLES INTO EARLY THIS EVENING AND
MAINLY ACROSS NORTHWEST AND NORTHERN IL. ADDITIONAL PRECIP IS
EXPECTED TO DEVELOP LATER THIS EVENING AND SPREAD NORTHEAST
OVERNIGHT INTO SATURDAY MORNING. THIS PRECIP WILL ALSO BE FOCUSED
ACROSS NORTHWEST/NORTHERN IL...INTO SOUTHERN WI. MODEL QPF AMOUNTS
NEAR THE IL/WI STATE LINE ARE IN THE 1 TO 1.5 INCH RANGE. THESE
AMOUNTS HAVE BEEN CONSISTENT BETWEEN RUNS AND VARIOUS MODELS SO IT
IS LIKELY SOME AREAS WILL SEE OVER AN INCH OF RAIN. HOWEVER...THESE
AMOUNTS APPEAR TO DROP OFF QUICKLY BETWEEN I-88 AND I-80 WITH MUCH
OF THE SOUTHEAST THIRD OR HALF OF THE CWA POSSIBLY STAYING DRY INTO
SATURDAY MORNING. INSTABILITY IS LIMITED AND LIGHTNING HAS BEEN
CONFINED TO THE STRONGEST STORMS/CONVECTION. THUNDER IS CERTAINLY
POSSIBLE TONIGHT BUT OVERALL COVERAGE SHOULD BE LIMITED AND HELD
SLIGHT CHANCE MENTION OF THUNDER TO HIGHER POP AREAS.
AFTER THE MAIN AREA OF RAIN MOVES NORTHEAST SATURDAY MORNING...
PRECIP ACROSS THE REST OF THE CWA WILL BE MORE SCATTERED...OR
ISOLATED...INTO THE LATE MORNING/EARLY AFTERNOON. APPEARS THERE
COULD BE NEW DEVELOPMENT IN THE EARLY/MID AFTERNOON BUT COVERAGE
POSSIBLY STILL JUST SCATTERED. THUS DIDN/T MAKE TOO MANY CHANGES
FROM CURRENT POPS IN THE 40-50 PERCENT RANGE.
TEMPS WILL ONLY SLOWLY FALL INTO THE LOWER/MID 60S TONIGHT AND HIGHS
ON SATURDAY WILL BE DEPENDENT ON PRECIP COVERAGE AND CLOUD COVER.
CURRENT FORECAST OF MID 70S NORTH TO LOWER 80S SOUTHEAST WILL
NEED SOME SUN TO OCCUR. SOUTHEASTERLY WINDS WILL KEEP THE IL SHORE
A BIT COOLER. CMS
&&
.LONG TERM...
307 PM CDT
SATURDAY NIGHT THROUGH FRIDAY...
THE LATEST LONGER TERM GUIDANCE IS INDICATING SOME CHANGES POSSIBLE
FOR THE LONGER RANGE TRENDS FOR TEMPERATURES AND PCPN...BUT THE
EARLIER PORTION OF THE LONG TERM FORECAST IS RELATIVELY CONSISTENT
WITH PREVIOUS RUNS.
THE GENERAL TREND FOR TEMPERATURES IS STILL FOR A WARMING TREND FOR
NEXT WEEK...BUT TEMPERATURES SHOULD STILL BE SLIGHTLY BELOW NORMAL
THROUGH SUNDAY. FOR SATURDAY NIGHT AND INTO EARLY SUNDAY...THERE
SHOULD STILL BE A CHANCE OF SOME LINGERING SHOWERS OR A FEW
THUNDERSTORMS...ESPECIALLY FOR NWRN INDIANA AS THE UPPER LEVEL
SHORTWAVE RESPONSIBLE FOR FOCUSING THE CONVECTIVE ACTIVITY LIFTS
OFF TO THE EAST AND WEAKENS. BY SUNDAY...LEE TROUGHING WILL DEVELOP
OVER THE WRN PLAINS AS A NORTHERN STREAM SHORTWAVE AND AN ASSOCIATED
SFC REFLECTION DROPS OUT OF THE CANADIAN ROCKIES AND INTO THE
PRAIRIES. THE OVERALL PATTERN WILL BECOME NEARLY STATIONARY THROUGH
MUCH OF NEXT WEEK AS THE SFC HIGH REMAINS PARKED OVER THE MID
ATLANTIC REGION WHILE THE TROUGH REMAINS OVER THE PLAINS. THIS WILL
HELP AID THE WARMING TREND AS SLY WINDS TRY TO DRAW MOISTURE NWD
FROM THE GLFMEX...THOUGH WEAK SFC RIDGING THROUGH THE NRN GULF COAST
MAY CAUSE SOME DELAY IN THE MOISTURE RETURN.
THE MAIN CHANGE TO THE EXTENDED FORECAST IS RELATED TO HOW THE
MODELS NOW HANDLE THE REMNANTS OF TS ERIKA. PREVIOUS RUNS OF THE
LONGER RANGE GUIDANCE HAD PREVIOUSLY LIMITED THE WESTWARD
PROGRESSION OF THE TROPICAL SYSTEM...WHILE THE LATEST RUNS ARE
HINTING THAT ERIKA COULD TRACK FARTHER WEST. SO...WHILE THERE IS
STILL A FAIR AMOUNT OF UNCERTAINTY IN HOW FAR WEST THE PERIPHERAL
EFFECT OF THE TROPICAL SYSTEM WILL EXTEND...AND WE ARE NOT TALKING
ABOUT THE TROPICAL SYSTEM ACTUALLY MOVING ANYWHERE CLOSE TO NRN
IL/IN...RATHER THE IDEA IS THAT IF THE TROPICAL SYSTEM CAN TRACK A
LITTLE FURTHER WEST...THEN THERE WILL BE GREATER MOISTURE TRANSPORT
INTO THE MIDWEST...AND AS A RESULT...GREATER CHANCES FOR SHRA/TSRA
AND MORE CLOUD COVER THAN PREVIOUSLY ANTICIPATED. SO HAVE BACKED
OFF A COUPLE DEGREES ON MAX TEMPS THROUGH THE EXTENDED PERIOD AS
WELL AS INTRODUCING PERIODIC SLIGHT CHANCE POPS AND A BIT MORE CLOUD
COVER.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* PERIOD OF RAIN OVERNIGHT INTO SATURDAY MORNING
* MVFR OR LOWER CIGS AND VSBY POSSIBLE SAT NIGHT
IZZI
//DISCUSSION...UPDATED 06Z...
WEAKENING STORM SYSTEM WILL BRING A PERIOD OF RAIN WITH POSSIBLE
PERIODIC MVFR VSBY LATE TONIGHT INTO SAT MORNING BEFORE RAIN
TAPERS OFF AND ENDS BY MIDDAY. SMALL CHANCE EXISTS FOR SOME ISOLD
SHRA OR PERHAPS A TSRA DURING THE LATE AFTERNOON AS WHAT IS LEFT
OF THE STORM SYSTEM FESTERS...BUT CHANCES LOOK TOO LOW TO INCLUDE
PRECIP IN TAFS AT THIS TIME. LIGHT EAST TO SOUTHEAST WINDS COULD
TURN MORE SOUTHERLY SAT MORNING BEFORE PROBABLY TURNING FAIRLY
LIGHT AND VARIABLE DURING THE AFTERNOON. SHOULD SEE A TENDENCY FOR
WINDS TO BECOME LIGHT NORTHEAST SAT NIGHT AND WITH AMPLE LOW LEVEL
MOISTURE AND RECENT RAINS COULD SEE SOME LIGHT FOG AND/OR STRATUS
DEVELOP.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM-HIGH CONFIDENCE IN RAIN LATE TONIGHT/SAT MORNING
* HIGH CONFIDENCE IN WINDS BELOW 10KT...BUT LOW CONFIDENCE IN
DIRECTION.
* LOW CONFIDENCE IN CIGS/VSBY SAT NIGHT
IZZI
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY...VFR. EAST WIND.
MONDAY...VFR. SOUTHEAST WIND.
TUESDAY...VFR. SOUTH WIND.
WEDNESDAY...SLT CHC TSRA. PRIMARILY VFR. SOUTH WIND.
THURSDAY...VFR. SOUTH WIND.
BMD
&&
.MARINE...
207 AM CDT
NARROW RIDGE OF HIGH PRESSURE STRETCHING FROM NEAR DETROIT TO
GREEN BAY COMBINED WITH WEAKENING LOW PRESSURE OVER IOWA WILL
RESULT IN A NARROW RIBBON OF STRONGER EASTERLY WINDS EARLY THIS
MORNING OVER PORTIONS OF CENTRAL LAKE MICHIGAN BEFORE BACKING MORE
SOUTHEAST LATER THIS MORNING THEN ULTIMATELY EASING THIS
AFTERNOON. WEAK LOW OVER IOWA WILL DISSIPATE TONIGHT AND REMAINDER
OF THE UPCOMING WEEK WILL SEE WEATHER OVER THE LAKE DOMINATED BY
HIGH PRESSURE ANCHORED OVER THE MID ATLANTIC AND NORTHEAST.
IZZI
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
108 AM CDT SAT AUG 29 2015
.UPDATE...
HAVE ADJUSTED POPS DOWNWARD THROUGH THE MID EVENING HOURS TO
ACCOUNT FOR RADAR AND NEAR-TERM GUIDANCE TRENDS. LEADING EDGE OF
SHORTWAVE TROUGH AND VORTICITY MAXIMA WILL MOVE EAST FROM
WISCONSIN THIS EVENING...KEEPING BEST FORCING FOR PRECIP NORTH OF
THE STATE LINE. THUS...JUST HAVE GENERALLY ISOLATED
SHRA/INTERMITTENT SPRINKLE MENTION THROUGH MID EVENING IN FAR
NORTHERN ILLINOIS. VERY DRY AIR NOTED AROUND 800 MB ON A RECENT
AMDAR SOUNDING FROM MDW WILL MAKE IT TOUGH FOR ANY STEADY PRECIP
UNTIL DRY AIR GETS ERODED. UPPER TROUGH/SHORTWAVE AXIS AND
SHEARED VORT MAX ALONG TROUGH AXIS WILL SLOWLY PROGRESS FROM IA TO
NORTHERN IL LATE THIS EVENING AND OVERNIGHT...BRINGING GRADUALLY
INCREASING SHRA/RAIN COVERAGE FROM NORTHWEST TO SOUTHEAST...BUT
MANY AREAS ALONG AND EAST OF AN EVANSTON TO PONTIAC LINE COULD
VERY WELL REMAIN DRY THROUGH DAYBREAK. VERY LITTLE IF ANY
INSTABILITY OVER AREA THROUGH THE NIGHT AND POOR MIDLEVEL LAPSE
RATES SUPPORT KEEPING SLIGHT CHANCE TSRA AT BEST. THE REST OF THE
FORECAST LOOKS TO BE ON TRACK.
RC
&&
.SHORT TERM...
TONIGHT AND SATURDAY...
250 PM...FORECAST CONCERNS INCLUDE PRECIP COVERAGE/TIMING AND
RAINFALL AMOUNTS.
LOW PRESSURE OVER WESTERN IOWA WILL SLOWLY MOVE EAST TONIGHT AND
EVENTUALLY DISSIPATE OVER NORTHERN ILLINOIS SATURDAY. FIRST WAVE OF
PRECIP IS GENERALLY LIFTING NORTHEAST INTO SOUTHERN WISCONSIN AND
THE MODELS SEEM TO HAVE THIS HANDLED FAIRLY WELL WITH THE HRRR ALSO
SHOWING JUST ISOLATED SHOWERS/SPRINKLES INTO EARLY THIS EVENING AND
MAINLY ACROSS NORTHWEST AND NORTHERN IL. ADDITIONAL PRECIP IS
EXPECTED TO DEVELOP LATER THIS EVENING AND SPREAD NORTHEAST
OVERNIGHT INTO SATURDAY MORNING. THIS PRECIP WILL ALSO BE FOCUSED
ACROSS NORTHWEST/NORTHERN IL...INTO SOUTHERN WI. MODEL QPF AMOUNTS
NEAR THE IL/WI STATE LINE ARE IN THE 1 TO 1.5 INCH RANGE. THESE
AMOUNTS HAVE BEEN CONSISTENT BETWEEN RUNS AND VARIOUS MODELS SO IT
IS LIKELY SOME AREAS WILL SEE OVER AN INCH OF RAIN. HOWEVER...THESE
AMOUNTS APPEAR TO DROP OFF QUICKLY BETWEEN I-88 AND I-80 WITH MUCH
OF THE SOUTHEAST THIRD OR HALF OF THE CWA POSSIBLY STAYING DRY INTO
SATURDAY MORNING. INSTABILITY IS LIMITED AND LIGHTNING HAS BEEN
CONFINED TO THE STRONGEST STORMS/CONVECTION. THUNDER IS CERTAINLY
POSSIBLE TONIGHT BUT OVERALL COVERAGE SHOULD BE LIMITED AND HELD
SLIGHT CHANCE MENTION OF THUNDER TO HIGHER POP AREAS.
AFTER THE MAIN AREA OF RAIN MOVES NORTHEAST SATURDAY MORNING...
PRECIP ACROSS THE REST OF THE CWA WILL BE MORE SCATTERED...OR
ISOLATED...INTO THE LATE MORNING/EARLY AFTERNOON. APPEARS THERE
COULD BE NEW DEVELOPMENT IN THE EARLY/MID AFTERNOON BUT COVERAGE
POSSIBLY STILL JUST SCATTERED. THUS DIDN/T MAKE TOO MANY CHANGES
FROM CURRENT POPS IN THE 40-50 PERCENT RANGE.
TEMPS WILL ONLY SLOWLY FALL INTO THE LOWER/MID 60S TONIGHT AND HIGHS
ON SATURDAY WILL BE DEPENDENT ON PRECIP COVERAGE AND CLOUD COVER.
CURRENT FORECAST OF MID 70S NORTH TO LOWER 80S SOUTHEAST WILL
NEED SOME SUN TO OCCUR. SOUTHEASTERLY WINDS WILL KEEP THE IL SHORE
A BIT COOLER. CMS
&&
.LONG TERM...
307 PM CDT
SATURDAY NIGHT THROUGH FRIDAY...
THE LATEST LONGER TERM GUIDANCE IS INDICATING SOME CHANGES POSSIBLE
FOR THE LONGER RANGE TRENDS FOR TEMPERATURES AND PCPN...BUT THE
EARLIER PORTION OF THE LONG TERM FORECAST IS RELATIVELY CONSISTENT
WITH PREVIOUS RUNS.
THE GENERAL TREND FOR TEMPERATURES IS STILL FOR A WARMING TREND FOR
NEXT WEEK...BUT TEMPERATURES SHOULD STILL BE SLIGHTLY BELOW NORMAL
THROUGH SUNDAY. FOR SATURDAY NIGHT AND INTO EARLY SUNDAY...THERE
SHOULD STILL BE A CHANCE OF SOME LINGERING SHOWERS OR A FEW
THUNDERSTORMS...ESPECIALLY FOR NWRN INDIANA AS THE UPPER LEVEL
SHORTWAVE RESPONSIBLE FOR FOCUSING THE CONVECTIVE ACTIVITY LIFTS
OFF TO THE EAST AND WEAKENS. BY SUNDAY...LEE TROUGHING WILL DEVELOP
OVER THE WRN PLAINS AS A NORTHERN STREAM SHORTWAVE AND AN ASSOCIATED
SFC REFLECTION DROPS OUT OF THE CANADIAN ROCKIES AND INTO THE
PRAIRIES. THE OVERALL PATTERN WILL BECOME NEARLY STATIONARY THROUGH
MUCH OF NEXT WEEK AS THE SFC HIGH REMAINS PARKED OVER THE MID
ATLANTIC REGION WHILE THE TROUGH REMAINS OVER THE PLAINS. THIS WILL
HELP AID THE WARMING TREND AS SLY WINDS TRY TO DRAW MOISTURE NWD
FROM THE GLFMEX...THOUGH WEAK SFC RIDGING THROUGH THE NRN GULF COAST
MAY CAUSE SOME DELAY IN THE MOISTURE RETURN.
THE MAIN CHANGE TO THE EXTENDED FORECAST IS RELATED TO HOW THE
MODELS NOW HANDLE THE REMNANTS OF TS ERIKA. PREVIOUS RUNS OF THE
LONGER RANGE GUIDANCE HAD PREVIOUSLY LIMITED THE WESTWARD
PROGRESSION OF THE TROPICAL SYSTEM...WHILE THE LATEST RUNS ARE
HINTING THAT ERIKA COULD TRACK FARTHER WEST. SO...WHILE THERE IS
STILL A FAIR AMOUNT OF UNCERTAINTY IN HOW FAR WEST THE PERIPHERAL
EFFECT OF THE TROPICAL SYSTEM WILL EXTEND...AND WE ARE NOT TALKING
ABOUT THE TROPICAL SYSTEM ACTUALLY MOVING ANYWHERE CLOSE TO NRN
IL/IN...RATHER THE IDEA IS THAT IF THE TROPICAL SYSTEM CAN TRACK A
LITTLE FURTHER WEST...THEN THERE WILL BE GREATER MOISTURE TRANSPORT
INTO THE MIDWEST...AND AS A RESULT...GREATER CHANCES FOR SHRA/TSRA
AND MORE CLOUD COVER THAN PREVIOUSLY ANTICIPATED. SO HAVE BACKED
OFF A COUPLE DEGREES ON MAX TEMPS THROUGH THE EXTENDED PERIOD AS
WELL AS INTRODUCING PERIODIC SLIGHT CHANCE POPS AND A BIT MORE CLOUD
COVER.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* PERIOD OF RAIN OVERNIGHT INTO SATURDAY MORNING
* MVFR OR LOWER CIGS AND VSBY POSSIBLE SAT NIGHT
IZZI
//DISCUSSION...UPDATED 06Z...
WEAKENING STORM SYSTEM WILL BRING A PERIOD OF RAIN WITH POSSIBLE
PERIODIC MVFR VSBY LATE TONIGHT INTO SAT MORNING BEFORE RAIN
TAPERS OFF AND ENDS BY MIDDAY. SMALL CHANCE EXISTS FOR SOME ISOLD
SHRA OR PERHAPS A TSRA DURING THE LATE AFTERNOON AS WHAT IS LEFT
OF THE STORM SYSTEM FESTERS...BUT CHANCES LOOK TOO LOW TO INCLUDE
PRECIP IN TAFS AT THIS TIME. LIGHT EAST TO SOUTHEAST WINDS COULD
TURN MORE SOUTHERLY SAT MORNING BEFORE PROBABLY TURNING FAIRLY
LIGHT AND VARIABLE DURING THE AFTERNOON. SHOULD SEE A TENDENCY FOR
WINDS TO BECOME LIGHT NORTHEAST SAT NIGHT AND WITH AMPLE LOW LEVEL
MOISTURE AND RECENT RAINS COULD SEE SOME LIGHT FOG AND/OR STRATUS
DEVELOP.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM-HIGH CONFIDENCE IN RAIN LATE TONIGHT/SAT MORNING
* HIGH CONFIDENCE IN WINDS BELOW 10KT...BUT LOW CONFIDENCE IN
DIRECTION.
* LOW CONFIDENCE IN CIGS/VSBY SAT NIGHT
IZZI
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY...VFR. EAST WIND.
MONDAY...VFR. SOUTHEAST WIND.
TUESDAY...VFR. SOUTH WIND.
WEDNESDAY...SLT CHC TSRA. PRIMARILY VFR. SOUTH WIND.
THURSDAY...VFR. SOUTH WIND.
BMD
&&
.MARINE...
310 PM CDT
HIGH PRESSURE OVER THE MID ATLANTIC REGION WILL MOVE VERY LITTLE
THROUGH THE MIDDLE OF NEXT WEEK. WEAK LOW PRESSURE OVER WESTERN
IOWA WILL WEAKEN AS IT MOVES INTO THE MIDDLE MISSISSIPPI VALLEY
AND DISSIPATES SATURDAY EVENING. ANOTHER AREA OF LOW PRESSURE IS
EXPECTED TO DROP OUT OF THE CANADIAN ROCKIES SUNDAY NIGHT WHILE A
TROUGH OF LOW PRESSURE DEVELOPS OVER THE WESTERN PLAINS. THIS
TROUGH AND THE HIGH OVER THE MID ATLANTIC REGION WILL MOVE LITTLE
OVER THE NEXT SEVERAL DAYS...KEEPING MODEST SOUTH TO SOUTHWEST
WINDS OVER THE LAKE FOR THE NEXT SEVERAL DAYS.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS LINCOLN IL
1142 PM CDT FRI AUG 28 2015
.UPDATE...
ISSUED AT 903 PM CDT FRI AUG 28 2015
THE DRY AIR IN PLACE ACROSS CENTRAL IL HAS CAUSED THE LEADING PUSH
OF SHOWERS TO DISSIPATE BEFORE REACHING THE ILLINOIS RIVER. THAT
SHOULD CONTINUE TO BE THE CASE UNTIL AT LEAST 06Z/1AM. WE EXPECT
BETTER POTENTIAL FOR RAIN TOMORROW AS THE LOW AND COLD FRONT
REACH WESTERN IL. THE WEAKENING OF THE ENTIRE LOW PRESSURE SYSTEM
AS IT REACHES ILLINOIS WILL SUPPORT KEEPING THE POPS IN THE LOW
CHANCE CATEGORY. WILL DIMINISH THE SOUTHERN EXTENT OF CHANCE POPS
BETWEEN 06Z AND 12Z, BASED ON TRENDS THIS EVENING. A VEIL OF HIGH
CLOUDS WILL KEEP LOW TEMPS WARMER THAN LAST NIGHT, WITH READINGS
MAINLY IN THE MID 60S. UPDATES THIS EVENING WILL BE MAINLY IN THE
WEATHER/POP AREA, AS THE REMAINDER OF THE FORECAST IS GENERALLY ON
TRACK.
&&
.SHORT TERM...(TONIGHT)
ISSUED AT 243 PM CDT FRI AUG 28 2015
AFTERNOON SURFACE MAP SHOWING LOW PRESSURE CENTERED NEAR OMAHA, WITH
A WARM FRONT EXTENDING NORTHEAST ACROSS IOWA AND A COLD FRONT INTO
CENTRAL KANSAS. MAIN ACTIVITY OF SHOWERS AND THUNDERSTORMS HAS BEEN
CLOSER TO THE WARM FRONT AND TRACKING NORTH OF OUR FORECAST AREA. A
GENERAL EASTWARD PROGRESSION OF THE BOUNDARIES IS EXPECTED OVER THE
NEXT SEVERAL HOURS, WITH THE COLD FRONT APPROACHING THE
ILLINOIS/IOWA BORDER TOWARD 3-4 AM. FORECAST SOUNDINGS ARE RATHER
DRY BELOW 12,000 FEET FROM ABOUT PEORIA EAST AND SOUTH, AND AM
STARTING TO GET CONCERNED THAT THERE WILL BE LITTLE MORE THAN
ISOLATED SHOWERS BETWEEN I-55 AND THE ILLINOIS RIVER TONIGHT.
HOWEVER, THE HRRR AND ARW MODELS ARE A BIT MORE AGGRESSIVE WITH
SHOWERS MOVING INTO THIS AREA AFTER 3 AM, SO WILL MAINTAIN CHANCE
POP`S ACROSS THE ILLINOIS RIVER VALLEY MAINLY FROM LATE EVENING
THROUGH OVERNIGHT. INSTABILITY IS A LITTLE MORE SPARSE THOUGH, WITH
THE CURRENT THUNDER ACTIVITY MAINLY NEAR THE UPPER LEVEL DISTURBANCE
TRACKING ACROSS CENTRAL IOWA, AND HAVE TRIMMED BACK THE THUNDER
POTENTIAL TO MAINLY WEST OF THE RIVER. OTHERWISE, HAVE MAINLY GONE
DRY EAST OF I-55. MILDER CONDITIONS EXPECTED OVERNIGHT WITH CLOUD
COVER MUCH MORE EXTENSIVE AND A SOUTHERLY FLOW, WITH MOST AREAS
DIPPING INTO THE MID 60S.
.LONG TERM...(SATURDAY THROUGH FRIDAY)
ISSUED AT 243 PM CDT FRI AUG 28 2015
LOW PRESSURE AREA AND ASSOCIATED FRONT WEST OF THE AREA WILL
CONTINUE TO SLOWLY MOVE EAST AND INTO THE CWA DURING THE WEEKEND.
HOWEVER...VERY LITTLE SUPPORT FOR THIS SYSTEM AS IT MOVES EAST SO
ALL MODELS HAVE THIS SYSTEM WEAKENING AS IT MOVES INTO THE AREA.
THEREFORE...WILL ONLY HAVE CHANCE POPS FOR SAT MORNING WEST OF I-55
AND THEN MOVE POPS EAST DURING THE AFTERNOON BUT REMAINING MAINLY
NORTH OF I-70 AS FRONT CONTINUES TO WEAKEN AND BECOME SOMEWHAT
PARALLEL TO THE FLOW AND VERY LACKING ON CONVERGENCE/SUPPORT. CHANCE
POPS FOR SAT NIGHT WILL CONTINUE AS THE UPPER LEVEL WAVE SHIFTS EAST
ACROSS THE AREA. PCPN WILL BE MAINLY SHOWERS AND ISOLATED
THUNDERSTORMS...DUE TO LACK OF FORCING AND INSTABILITY. BY
SUNDAY...THE WAVE SHOULD BE VERY WEAK AND EAST OF THE CWA...SO WILL
ONLY HAVE SLIGHT CHANCE POPS. FOR REMAINDER OF THE WEEKEND AND INTO
THE BEGINNING OF NEXT WEEK...DRY CONDITIONS CAN BE EXPECTED AS HIGH
PRESSURE BEGINS TO BUILD IN THE WEST AND PUSH INTO THE NORTHERN PART
OF THE AREA.
BEGINNING TUE AND THROUGH MOST OF THE WEEK...A COUPLE OF MODELS
BRING REMNANTS OF TS ERIKA INTO THE AREA. HOWEVER...THIS IS
DEPENDENT ON WHERE THE TS GOES. AND IT IS FAR ENOUGH AWAY IN TIME
THAT WILL JUST KEEP CLOSE TO WHAT THE CRINT HAS...AND THAT IS JUST
SLIGHT CHANCE POPS IN SOME AREAS FOR WED THROUGH THUR. SLIGHT CHANCE
POPS WILL BE IN THE GRIDS BUT NOT MENTIONED IN THE WORDED FORECAST.
TEMPS THROUGH THE WEEKEND WILL BE TEMPERED DUE TO CLOUD COVER AND
SCATTERED PCPN...BUT STILL EXPECTING THEM TO RISE INTO THE 80S FOR
THE WEEKEND. BY NEXT WEEK...WITH UPPER LEVEL RIDGING BUILDING INTO
THE AREA AND DEWPOINTS BEING DRIER...EXPECTING TEMPS TO RISE INTO
THE UPPER 80S TO AROUND 90 FOR THE ENTIRE WEEK. THIS WILL BE MUCH
ABOVE NORMAL FOR THE BEGINNING OF SEPT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1142 PM CDT FRI AUG 28 2015
LOW PRESSURE CENTERED IN WESTERN IOWA WILL CONTINUE TO DRIFT EAST
TONIGHT. IT WILL GRADUALLY DISSIPATE NEAR WESTERN ILLINOIS
SATURDAY AFTERNOON/EVE. SHOWERS HAVE EXPANDED IN COVERAGE BETWEEN
04Z-05Z, AND RAIN IS STARTING TO REACH THE GROUND FROM CLOUD
BASES AT 8K FT OR HIGHER. SCATTERED RAIN SHOWERS WILL PERIODICALLY
AFFECT THE TERMINAL SITES OVER THE NEXT 18 HOURS, BEFORE
DISSIPATING SATURDAY EVENING. THE CHANCES ONLY WARRANTED A VCSH
AND VFR CLOUD COVER, BASED ON FORECAST SOUNDINGS FROM HRRR AND
RAP/NAM OUTPUT. USED ONLY VCSH IN ALL TAFS TO ACCOUNT FOR PRECIP,
AS TIMING WILL BE HIGHLY VARIABLE IN TERMS OF TIMING AND LOCATION.
ENDED ALL MENTION OF PRECIP BEFORE 00Z/30. WINDS ARE EXPECTED TO
REMAIN SOUTH THROUGH AT LEAST 18Z, THEN BEGIN TO SHIFT TO THE
SOUTHWEST AS THE LOW AND COLD FRONT APPROACH WESTERN ILLINOIS.
PREVAILING WIND SPEEDS SHOULD REMAIN 10KT OR LESS THROUGH TOMORROW
AFTERNOON.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SHIMON
SHORT TERM...GEELHART
LONG TERM...AUTEN
AVIATION...SHIMON
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1255 AM EDT SAT AUG 29 2015
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 313 PM EDT FRI AUG 28 2015
HIGH PRESSURE IS EXPECTED ACROSS THE AREA THROUGH TONIGHT. A
WEAK FRONTAL SYSTEM WILL SETTLE INTO THE OHIO VALLEY THIS WEEKEND.
HIGH PRESSURE WILL BUILD BACK INTO THE AREA FOR THE EARLY NEXT WEEK.
A FEW DISTURBANCES MAY MOVE THROUGH CENTRAL INDIANA THROUGH THE
MIDDLE TO END OF THE NEXT WORK WEEK.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 948 PM EDT FRI AUG 28 2015
UPPED CLOUDS A BIT IN THE WEST TONIGHT BASED ON LATEST TRENDS SEEN
ON SATELLITE. HRRR TRIES TO BRING IN A FEW SHOWERS LATE TONIGHT BUT
DO NOT BELIEVE THERE WILL BE ENOUGH FORCING TO GENERATE MUCH RAIN.
CANNOT RULE OUT A FEW SPRINKLES AS DYING SHOWERS MOVE IN LATE...BUT
NOT ENOUGH EXPECTED TO ADD THESE TO THE FORECAST.
TEMPERATURE FORECAST LOOKS GOOD.
PREVIOUS DISCUSSION FOLLOWS...
WILL KEEP THE FORECAST DRY FOR TONIGHT AS SURFACE HIGH PRESSURE
HOLDS ON. SHORT TERM MODELS AND LATEST TRENDS TO THE WEST INDICATE
THERE WILL BE A GRADUAL INCREASE OF MID AND HIGH LEVEL CLOUD COVER.
A MOS BLEND FOR LOWS LOOKS REASONABLE GIVEN THE EXPECTED CLOUD COVER
FOR LOW TEMPERATURES 60-65.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
ISSUED AT 313 PM EDT FRI AUG 28 2015
MODELS REMAIN INCONSISTENT WITH REGARD TO MOISTURE AMOUNTS AND TRACK
OF A WEAK FRONTAL SYSTEM...WHICH IS ASSOCIATED WITH AN UPPER TROUGH
AND EXPECTED TO MOVE THROUGH THIS WEEKEND. INSTABILITY IS NOT GREAT
BUT AT LEAST WARRANTS MENTION OF SCATTERED THUNDERSTORMS DURING THIS
WEEKEND. BEST CHANCES APPEAR TO BE SATURDAY EVENING WHEN THE FRONTAL
SYSTEM IS PROJECTED TO CROSS THE AREA. WEAK CHANCES WILL EXIST
SATURDAY AFTERNOON AND AGAIN ON SUNDAY INTO SUNDAY NIGHT. SINCE THE
MODELS HAVE YET TO COME TO A CONSENSUS SOLUTION AND REMAIN
INCONSISTENT...KEPT CHANCES BELOW THE "LIKELY" CATEGORY...FOR NOW.
PRECIP CHANCES WILL QUICKLY BEGIN TO DWINDLE BY EARLY MONDAY
MORNING AS A RIDGE OF HIGH PRESSURE QUICKLY REESTABLISHES ITS
HOLD OVER THE REGION. DRY CONDITIONS ARE GENERALLY EXPECTED TO
KICK OFF THE WORK WEEK. AND TEMPERATURES WILL HAVE SLOWLY
ACCLIMATED BACK TO SEASONAL NORMAL BY MONDAY. WELCOME BACK
SUMMER...
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ISSUED AT 252 PM EDT FRI AUG 28 2015
BROAD UPPER RIDGING WILL BE ACROSS THE AREA DURING THE LONG TERM.
HOWEVER THE INFLUENCE OF MOISTURE FROM ERIKA NOW LOOKS LIKE IT COULD
COME INTO PLAY IN THE MIDWEST/OHIO VALLEY DURING THE WEEK. WITH
MODELS TRENDING TOWARD BRINGING SOME ENERGY AROUND THE UPPER RIDGE
AND BRING MOISTURE NORTH THOUGHT IT PRUDENT TO FOLLOW THAT TREND AND
INCLUDE SOME SLIGHT CHANCES FOR THUNDERSTORMS DURING THE DAY FROM
WEDNESDAY THROUGH FRIDAY. THE INITIALIZATION FOLLOWED THIS TREND AS
WELL AND JUST NEEDED SOME QUALITY CONTROL TWEAKS. TEMPERATURE-WISE
LOOKING AT HIGHS JUST ABOVE NORMAL IN THE MID TO UPPER 80S FROM THE
INITIALIZATION AND THESE LOOK GOOD. HIGHS IN THE 90S NOT OUT OF THE
QUESTION BUT SHOULD ONLY BE ATTAINABLE IF THE TROPICAL MOISTURE
DOESN/T MAKE IT THIS WAY.
&&
.AVIATION /DISCUSSION FOR 290600Z TAF ISSUANCE/...
ISSUED AT 1235 AM EDT SAT AUG 29 2015
OUTSIDE OF ANY CONVECTION LATE IN THE PERIOD...VFR EXPECTED THROUGH
THE PERIOD.
MID CLOUD WILL CONTINUE TO INCREASE OVERNIGHT. THIS SHOULD KEEP FOG
AT BAY...BUT IF BREAKS LAST LONG ENOUGH...COULD SEE SOME MVFR FOG AT
THE OUTLIER SITES.
SCATTERED LIGHT SHOWERS ARE POSSIBLE SATURDAY MORNING...BUT BETTER
CHANCES FOR SCATTERED CONVECTION ARRIVE LATE AFTERNOON INTO THE
EVENING. FOR NOW HAVE ADDED A PROB30 GROUP FOR STORMS THEN.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF/50
SHORT TERM...SMF
LONG TERM....CP
AVIATION...50/JH
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
721 PM CDT SUN AUG 30 2015
.UPDATE...
ISSUED AT 720 PM CDT SUN AUG 30 2015
HAVE GONE OUT WITH A DENSE FOG ADVISORY FOR MOST OF EASTERN IA AND
ADJACENT IL COUNTIES ALONG I-80 FOR LATE TONIGHT THROUGH EARLY
MORNING MONDAY. CONDITIONS ARE SIMILAR TO LAST NIGHT...WITH THE
SAME AIRMASS IN PLACE AND NEARLY CALM WINDS UNDER THE W-E SURFACE
RIDGE OVERHEAD. SURFACE DEWPOINTS ARE HIGHER IN MANY PLACES THAN
LAST NIGHT AT THIS TIME. CROSSOVER TECHNIQUE...USING DEWPOINTS AT
PEAK HEATING AND CURRENT FORECAST LOWS SUPPORTS WIDESPREAD FOG.
THE FOG COULD BE A LITTLE LATER TO DEVELOP DUE TO THE HIGHER
TEMPERATURES AND TEMP/DEWPOINT DEPARTURES AT THIS TIME TONIGHT VS
THIS TIME LAST NIGHT.
&&
.SYNOPSIS...
ISSUED AT 333 PM CDT SUN AUG 30 2015
SURFACE RIDGE AXIS EXTENDS FROM THE GREAT LAKES THROUGH THE CWA
AND INTO THE SOUTH CENTRAL PLAINS AT MID AFTN. THE FAIRLY
WIDESPREAD DENSE FOG BURNED OFF BY MID TO LATE AM LEAVING BEHIND
FAIRLY EXTENSIVE STRATUS WHICH HAS BEEN STEADILY ERODING FROM THE
SOUTH AND EVOLVING INTO SCATTERED STRATOCU DECK. THE INCREASING
PEAKS OF SUNSHINE HAS HELPED TO BUMP TEMPS UP TO NEAR LATE
AUGUST NORMALS WITH MANY AREAS IN THE UPPER 70S TO LOWER 80S.
THE EXCEPTION BEING MAINLY PORTIONS OF NORTHEAST IA WHERE STRATUS
SILL LINGERS AND AIDING IN HOLDING TEMPS DOWN IN THE LOWER 70S
ATTIM... BUT WITH MORE LATE DAY SUNSHINE SHOULD SEE TEMPS IN THESE
AREAS SURGE LATE. PATTERN ALOFT FEATURES AN AMPLIFIED RIDGE /HEAT DOME/
THROUGH THE PLAINS IN ADVANCE OF A PACIFIC NORTHWEST TROUGH. THE NEXT
24 HOURS WILL SEE THIS RIDGE AND WARMER AIR BUILD INTO THE MID-
MISSISSIPPI VLY AS THE PACIFIC NORTHWEST TROUGH SHIFTS ACROSS THE
NORTHERN ROCKIES. THIS WILL RESULT IN CONTINUATION OF DRY CONDITIONS
WITH WARMER TEMPS ON MONDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 333 PM CDT SUN AUG 30 2015
MAIN CHALLENGE REMAINS LOW CLOUDS AND FOG POTENTIAL WITH IMPACT ON
TEMPS.
FOLLOWING TRENDS PER SATL AND OBS FROM LATE AFTN WITH DECREASING STRATUS
NORTHWEST CWA EVOLVING INTO SCATTERED STRATOCUMULUS THEN MOSTLY
CLEAR FOR A TIME THIS EVENING. LATE EVENING AND OVERNIGHT WITH
CONTINUED WEAK WINDS AND ABUNDANT LOW LEVEL MOISTURE EXPECT
REDEVELOPMENT OF FOG DENSE IN SOME AREAS... WITH ALSO SOME STRATUS
POSSIBLE ALTHOUGH UNCERTAIN ON EXTENT OF ANY STRATUS FORMATION WITH
LATEST RAP AND NAM MODELS SHOWING AROUND 15+ KTS OF WIND JUST ABOVE
MOIST LAYER WHICH MAY BE SUFFICIENT MIXING TO OFFSET WIDESPREAD STRATUS
FORMATION AND WITH JUST DIURNAL CUMULUS ACROSS MO DON/T EXPECT ANY
ADVECTION OF LOW DECK. MIN TEMPS WILL BE CHALLENGING AND DEPENDENT ON
FOG AND STRATUS TRENDS. AS WE SAW THIS AM... POTENTIAL FOR AREAS THAT
STAY CLEAR LONGER TO RADIATE DOWN INTO THE 50S WITH NEAR CALM WINDS.
OTHERWISE... WITH TEMPS A BIT WARMER TODAY FOR MANY AND WITH MID AFTN
DEWPTS IN MID/UPPER 60S I HAVE KEPT LOWS MAINLY IN RANGE OF 60-67 DEGS.
ON MONDAY...ANY FOG SHOULD BURN OFF A BIT EARLIER TOMORROW BY MID AM
WITH A BIT STRONGER SOUTHERLY WIND DEVELOPING OF 5-10 KTS. ANY
STRATUS SHOULD LIFT TO FAIR WX CUMULUS DURING AFTERNOON AND GENERALLY
MOSTLY SUNNY SKIES. THIS WILL ALLOW TEMPS TO CLIMB WELL INTO THE 80S
WITH WIDESPREAD MID TO A FEW UPPER 80S. THESE TEMPS COUPLED WITH
DEWPTS WELL IN THE 60S TO NEAR 70 DEGS WILL MAKE FOR VERY WARM FEEL
WITH HEAT INDICES AROUND 90/L90S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 333 PM CDT SUN AUG 30 2015
OVERVIEW...BUILDING AND PERSISTENT UPPER-LEVEL RIDGE OVER THE
CENTRAL U.S. WILL LEAD TO ABOVE AVERAGE TEMPERATURES AND HUMID
CONDITIONS THROUGH THE EXTENDED PERIOD. OVERALL CHANCES FOR RAIN
ARE VERY LOW.
TUESDAY AND WEDNESDAY...1000-500MB THICKNESS VALUES ARE FORECAST TO
BE NEAR 576-579 DAM WITH 850MB TEMPS IN THE UPPER TEENS/NEAR 20 C.
FORECAST HIGHS ARE IN THE UPPER 80S TO NEAR 90 F...WITH HEAT INDICES
IN THE LOWER TO MIDDLE 90S.
A SHORTWAVE TROUGH FROM REMNANT MONSOONAL CONVECTION MAY TRAVERSE
THE MIDWEST ON WEDNESDAY BUT MODELS TRACK IT NW OF E IOWA/W
ILLINOIS. CONSEQUENTLY KEPT THE FORECAST DRY.
THURSDAY THROUGH SATURDAY...RAW MODELS STILL APPEAR TO HAVE A WARM
BIAS AND ARE PROJECTING LOWER TO MIDDLE 90S. HUMID
CONDITIONS...850MB TEMPS IN THE UPPER TEENS TO POSSIBLY LOWER 20S
CELSIUS...AND A LOWER SEPTEMBER SUN ANGLE BACK A TEMP FORECAST
SLIGHTLY BELOW THE HIGHER RAW MODEL DATA.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 631 PM CDT SUN AUG 30 2015
A WEAK FLOW REGIME UNDER HIGH PRESSURE...ALONG WITH ABUNDANT LOW
LEVEL MOISTURE WILL AGAIN LEAD TO AREAS OF FOG TONIGHT. THIS IS
LIKELY TO DEVELOP BETWEEN 04Z AND 06Z...AND HAVE TRENDED
CONDITIONS BECOMING MVFR AT ALL SITES DURING THIS PERIOD. THROUGH
THIS TIME...THICK SMOKE FROM WESTERN WILDFIRES WILL PRODUCE HAZE
ALOFT. FROM 06Z THROUGH THE REST OF THE NIGHT...WIDESPREAD IFR TO
VLIFR IS AGAIN LIKELY. FOR NOW...IT APPEARS THE BRL SITE IS MOST
LIKELY TO EXPERIENCE THE LOWEST CONDITIONS. MONDAY MORNING...THE
FOG WILL AGAIN BE SLOW TO CLEAR AND HAVE OPTIMISTICALLY TRENDED
ALL SITES BACK TO MVFR VISIBILITIES BETWEEN 15Z AND 17Z.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...DENSE FOG ADVISORY FROM 2 AM TO 8 AM CDT MONDAY FOR BENTON-CEDAR-
CLINTON-DES MOINES-HENRY IA-IOWA-JACKSON-JEFFERSON-JOHNSON-
JONES-KEOKUK-LEE-LINN-LOUISA-MUSCATINE-SCOTT-VAN BUREN-
WASHINGTON.
IL...DENSE FOG ADVISORY FROM 2 AM TO 8 AM CDT MONDAY FOR HENDERSON-
HENRY IL-MERCER-ROCK ISLAND-WHITESIDE.
MO...NONE.
&&
$$
UPDATE...SHEETS
SYNOPSIS...MCCLURE
SHORT TERM...MCCLURE
LONG TERM...UTTECH
AVIATION...SHEETS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
631 PM CDT SUN AUG 30 2015
.SYNOPSIS...
ISSUED AT 333 PM CDT SUN AUG 30 2015
SURFACE RIDGE AXIS EXTENDS FROM THE GREAT LAKES THROUGH THE CWA
AND INTO THE SOUTH CENTRAL PLAINS AT MID AFTN. THE FAIRLY
WIDESPREAD DENSE FOG BURNED OFF BY MID TO LATE AM LEAVING BEHIND
FAIRLY EXTENSIVE STRATUS WHICH HAS BEEN STEADILY ERODING FROM THE
SOUTH AND EVOLVING INTO SCATTERED STRATOCU DECK. THE INCREASING
PEAKS OF SUNSHINE HAS HELPED TO BUMP TEMPS UP TO NEAR LATE
AUGUST NORMALS WITH MANY AREAS IN THE UPPER 70S TO LOWER 80S.
THE EXCEPTION BEING MAINLY PORTIONS OF NORTHEAST IA WHERE STRATUS
SILL LINGERS AND AIDING IN HOLDING TEMPS DOWN IN THE LOWER 70S
ATTIM... BUT WITH MORE LATE DAY SUNSHINE SHOULD SEE TEMPS IN THESE
AREAS SURGE LATE. PATTERN ALOFT FEATURES AN AMPLIFIED RIDGE /HEAT DOME/
THROUGH THE PLAINS IN ADVANCE OF A PACIFIC NORTHWEST TROUGH. THE NEXT
24 HOURS WILL SEE THIS RIDGE AND WARMER AIR BUILD INTO THE MID-
MISSISSIPPI VLY AS THE PACIFIC NORTHWEST TROUGH SHIFTS ACROSS THE
NORTHERN ROCKIES. THIS WILL RESULT IN CONTINUATION OF DRY CONDITIONS
WITH WARMER TEMPS ON MONDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 333 PM CDT SUN AUG 30 2015
MAIN CHALLENGE REMAINS LOW CLOUDS AND FOG POTENTIAL WITH IMPACT ON
TEMPS.
FOLLOWING TRENDS PER SATL AND OBS FROM LATE AFTN WITH DECREASING STRATUS
NORTHWEST CWA EVOLVING INTO SCATTERED STRATOCUMULUS THEN MOSTLY
CLEAR FOR A TIME THIS EVENING. LATE EVENING AND OVERNIGHT WITH
CONTINUED WEAK WINDS AND ABUNDANT LOW LEVEL MOISTURE EXPECT
REDEVELOPMENT OF FOG DENSE IN SOME AREAS... WITH ALSO SOME STRATUS
POSSIBLE ALTHOUGH UNCERTAIN ON EXTENT OF ANY STRATUS FORMATION WITH
LATEST RAP AND NAM MODELS SHOWING AROUND 15+ KTS OF WIND JUST ABOVE
MOIST LAYER WHICH MAY BE SUFFICIENT MIXING TO OFFSET WIDESPREAD STRATUS
FORMATION AND WITH JUST DIURNAL CUMULUS ACROSS MO DON/T EXPECT ANY
ADVECTION OF LOW DECK. MIN TEMPS WILL BE CHALLENGING AND DEPENDENT ON
FOG AND STRATUS TRENDS. AS WE SAW THIS AM... POTENTIAL FOR AREAS THAT
STAY CLEAR LONGER TO RADIATE DOWN INTO THE 50S WITH NEAR CALM WINDS.
OTHERWISE... WITH TEMPS A BIT WARMER TODAY FOR MANY AND WITH MID AFTN
DEWPTS IN MID/UPPER 60S I HAVE KEPT LOWS MAINLY IN RANGE OF 60-67 DEGS.
ON MONDAY...ANY FOG SHOULD BURN OFF A BIT EARLIER TOMORROW BY MID AM
WITH A BIT STRONGER SOUTHERLY WIND DEVELOPING OF 5-10 KTS. ANY
STRATUS SHOULD LIFT TO FAIR WX CUMULUS DURING AFTERNOON AND GENERALLY
MOSTLY SUNNY SKIES. THIS WILL ALLOW TEMPS TO CLIMB WELL INTO THE 80S
WITH WIDESPREAD MID TO A FEW UPPER 80S. THESE TEMPS COUPLED WITH
DEWPTS WELL IN THE 60S TO NEAR 70 DEGS WILL MAKE FOR VERY WARM FEEL
WITH HEAT INDICES AROUND 90/L90S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 333 PM CDT SUN AUG 30 2015
OVERVIEW...BUILDING AND PERSISTENT UPPER-LEVEL RIDGE OVER THE
CENTRAL U.S. WILL LEAD TO ABOVE AVERAGE TEMPERATURES AND HUMID
CONDITIONS THROUGH THE EXTENDED PERIOD. OVERALL CHANCES FOR RAIN
ARE VERY LOW.
TUESDAY AND WEDNESDAY...1000-500MB THICKNESS VALUES ARE FORECAST TO
BE NEAR 576-579 DAM WITH 850MB TEMPS IN THE UPPER TEENS/NEAR 20 C.
FORECAST HIGHS ARE IN THE UPPER 80S TO NEAR 90 F...WITH HEAT INDICES
IN THE LOWER TO MIDDLE 90S.
A SHORTWAVE TROUGH FROM REMNANT MONSOONAL CONVECTION MAY TRAVERSE
THE MIDWEST ON WEDNESDAY BUT MODELS TRACK IT NW OF E IOWA/W
ILLINOIS. CONSEQUENTLY KEPT THE FORECAST DRY.
THURSDAY THROUGH SATURDAY...RAW MODELS STILL APPEAR TO HAVE A WARM
BIAS AND ARE PROJECTING LOWER TO MIDDLE 90S. HUMID
CONDITIONS...850MB TEMPS IN THE UPPER TEENS TO POSSIBLY LOWER 20S
CELSIUS...AND A LOWER SEPTEMBER SUN ANGLE BACK A TEMP FORECAST
SLIGHTLY BELOW THE HIGHER RAW MODEL DATA.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 631 PM CDT SUN AUG 30 2015
A WEAK FLOW REGIME UNDER HIGH PRESSURE...ALONG WITH ABUNDANT LOW
LEVEL MOISTURE WILL AGAIN LEAD TO AREAS OF FOG TONIGHT. THIS IS
LIKELY TO DEVELOP BETWEEN 04Z AND 06Z...AND HAVE TRENDED
CONDITIONS BECOMING MVFR AT ALL SITES DURING THIS PERIOD. THROUGH
THIS TIME...THICK SMOKE FROM WESTERN WILDFIRES WILL PRODUCE HAZE
ALOFT. FROM 06Z THROUGH THE REST OF THE NIGHT...WIDESPREAD IFR TO
VLIFR IS AGAIN LIKELY. FOR NOW...IT APPEARS THE BRL SITE IS MOST
LIKELY TO EXPERIENCE THE LOWEST CONDITIONS. MONDAY MORNING...THE
FOG WILL AGAIN BE SLOW TO CLEAR AND HAVE OPTIMISTICALLY TRENDED
ALL SITES BACK TO MVFR VISIBILITIES BETWEEN 15Z AND 17Z.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...MCCLURE
SHORT TERM...MCCLURE
LONG TERM...UTTECH
AVIATION...SHEETS
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1139 PM CDT FRI AUG 28 2015
.SHORT TERM /TONIGHT/...
ISSUED AT 358 PM CDT FRI AUG 28 2015
HEAVY RAIN WILL PERSIST ACROSS THE NORTHEAST THROUGH THE
EVENING. LATEST HRRR RUN KEEPS CONVECTION GOING IN THE FAR EAST
THROUGH 04-05Z TIME FRAME AND LEANED TOWARD THIS SOLUTION FOR
POPS/WX. THE WARM RAIN PROCESSES CURRENTLY AFFECTING THE FLASH FLOOD
WARNED AREAS ARE PRODUCING 2-4 INCH PER HOUR RAINFALL RATES. STRONG
DEEP MOISTURE CONVERGENCE OVER THE WATERLOO AREA WITH ROUGHLY 1.5-2
INCH PRECIPITABLE WATER AND WARM CLOUD DEPTHS TO AROUND 4000 METERS
IS ENOUGH TO CONTINUE THE HEAVY RAIN THREAT BEFORE SURFACE LOW IN
WESTERN IOWA PUSHES FURTHER EAST LATER THIS EVENING. POTENTIAL FOR
HEAVY RAIN TO CONTINUE IN THE EAST TO NORTHEAST SECTIONS OF THE
FORECAST AREA THROUGH 03Z TONIGHT...TO COINCIDE WITH THE LATEST HRRR
THINKING. OTHER CONCERN IS FOG OVERNIGHT WITH PLENTY OF MOISTURE AND
VERY LITTLE FLOW AT THE SURFACE A WEAK SURFACE RIDGE BUILDS INTO
WESTERN IOWA. HAVE MENTIONED PATCHY FOG PAST 09Z WEST OF I-35.
.LONG TERM /SATURDAY THROUGH FRIDAY/...
ISSUED AT 358 PM CDT FRI AUG 28 2015
THE WEATHER WILL GENERALLY BE QUIET IN THE LONGER TERM WITH UPPER
RIDGING BUILDING INTO THE CENTRAL UNITED STATES. THICKNESSES WILL
INCREASE WITH TEMPERATURES CORRESPONDINGLY RESPONDING WITH HIGHS
CLIMBING ABOVE NORMAL...LIKELY TOWARD 90 BY EARLY NEXT
WEEK...ESPECIALLY IN THE SOUTH AND WEST. BOTH GFS AND EURO
INDICATED A WEAK SYSTEM PULLING NORTHEAST ON TUESDAY INTO THE
PLAINS WHICH MAY BRING THE THREAT OF ISOLATED THUNDER INTO THE
NORTHWEST PORTIONS OF IOWA BY LATER IN THE DAY INTO TUESDAY NIGHT.
OTHERWISE...THE RIDGE WILL REMAIN IN PLACE INTO LATE IN THE WEEK
WITH THE VERY WARM TEMPERATURES AND LITTLE THREAT OF PRECIPITATION.
&&
.AVIATION...29/06Z
ISSUED AT 1139 PM CDT FRI AUG 28 2015
SFC LOW STILL HAS SHIFTED TO SCEN IA AND WILL CONTINUE TO SHIFT EAST
THROUGH 12Z. LIGHT PRECIP WILL CONTINUE OVER THE FAR EASTERN TAF
LOCATIONS FOR A COUPLE MORE HOURS. MAIN CONCERN OVER IS IFR/LIFR
CIGS AND FOG POTENTIAL WITH HALF MILE VSBYS AND LOCALLY A QUARTER OR
LESS VSBY POSSIBLE. LOW CLOUDS AND FOG WILL SLOWLY BURN OFF THROUGH
LATE MORNING. A COUPLE MODELS HINT AT THE COLD FRONT DEVELOPING
STORMS DURING PEAK HEATING MAINLY AFFECTING KOTM BUT CONFIDENCE IN
THIS OCCURRING AT THIS POINT IS LOW.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...COGIL
AVIATION...FAB
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1242 PM CDT SAT AUG 29 2015
.UPDATE...
ISSUED AT 1032 AM CDT SAT AUG 29 2015
Upstream 12Z raob at Omaha indicate a 500-700 ft stratus deck
advecting south and southeast towards northeast Kansas. Current
indications from the latest RAP and HRRR forecast soundings
suggest the low level saturation at 2500 ft to persist through
late afternoon so have adjusted to mostly cloudy skies through
most of the day. Also lowered highs about 5-7 degrees to the upper
70s and lower 80s. Will continue to monitor trends, especially
over north central areas where earlier clearing will quickly warm
temps.
&&
...Update to aviation forecast discussion...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 231 AM CDT SAT AUG 29 2015
Early this morning an upper level trough extended from the northern
Great Lakes...southwest across northern MO into eastern KS. The
surface cold front was moving southeast of the CWA. A broad upper
level ridge was located across the west central US.
The upper trough will shear apart with the more amplified northern
branch moving east across the Great Lakes States. The southern
section of the H5 trough will dig south across northeast OK through
the day. The model forecast soundings show wrap around low-level
moisture will advect southeast across northeast and east central KS
this morning. The low clouds should increase towards sunrise across
the eastern half of the CWA. I cannot rule out a few sprinkles but
the stronger ascent for rain showers and thunderstorms will be east
and south of the CWA. The clouds will gradually erode from west to
east across northeast and east central KS through the late morning
and early afternoon hours. Skies will remain clear across the
western counties of the CWA and patchy fog may develop before
sunrise but should mix out by 8 AM. Most areas will become mostly
sunny during the mid afternoon hours, though a few more clouds may
continue across the southeast counties through the afternoon hours.
Highs will be in the lower 80s across most of the CWA. The western
counties will receive more insolation and may reach into the mid 80s
for afternoon highs.
Tonight...The H5 trough digging south-southwest across east central
OK will cause a sfc and 850mb low to develop across central and
eastern OK. Some of the numerical models develop weak isentropic
lift across southeast KS and western MO. The extreme southeast
counties may see a few isolated showers but at this time I will keep
14 pops across the southeast counties of the CWA. Once again some
patchy fog may develop across north central KS by
sunrise...especially if skies remain clear through the night.
Overnight lows will drop to around 60 degrees across the western
counties of the CWA with lower to mid 60s across east central KS.
.LONG TERM...(Sunday THROUGH Friday)
ISSUED AT 231 AM CDT SAT AUG 29 2015
Remnants of upper trough moving through the area tonight will
weaken and leave a vort max in the vicinity of southern MO that
remains nearly stationary through Monday. This feature will
result in scattered clouds and a few showers that could extend
into extreme east central and southeast KS during this time. While
isolated showers aren`t out of the question in our far
southeastern forecast area south of I35, chances are low enough
that I did not include in any products at this time.
Other than the influence of the aforementioned vort max, an upper
ridge axis will extend from the southern Rockies into the Upper
Midwest early next week. From Tuesday through Wednesday, a
shortwave trough will move from the central Rockies to the Upper
Midwest, flattening the ridge axis and producing lift out ahead of
it. Main dynamics and lift with this system will be focused to
our north, but medium range models continue to have continuity in
producing QPF down into northeast KS with the best chance Tuesday
night.
After that, upper ridge builds back in which should keep the
eastern third of KS dry through the rest of the work week.
Pattern is favorable for temperatures to average several degrees
above normal for late August with highs near 90 for most of the
week and lows in the 65 to 70 degree range.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z Sunday AFTERNOON)
ISSUED AT 1235 PM CDT SAT AUG 29 2015
Persistent MVFR cigs will remain pivoted around a 850 mb front
this afternoon, while dry air coming from the northeast attempts
to scatter cloud deck by 00Z tonight. Best chances for this
occurring is over KMHK. Otherwise expect the MVFR stratus to
remain in place overnight with some guidance indicating fog
developing underneath the frontal inversion. This unusual scenario
for this time of year leads to uncertainty in how low visibilitieswill
be based on what occurs with the stratus this afternoon. For now,
have introduced IFR 10Z to 15Z for low stratus and fog at all
sites. May need to monitor trends to adjust timing, but believe
the MVFR stratus will linger through at least 18Z Sunday.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Bowen
SHORT TERM...Gargan
LONG TERM...GDP
AVIATION...Bowen
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1037 AM CDT SAT AUG 29 2015
.UPDATE...
ISSUED AT 1032 AM CDT SAT AUG 29 2015
Upstream 12Z raob at Omaha indicate a 500-700 ft stratus deck
advecting south and southeast towards northeast Kansas. Current
indications from the latest RAP and HRRR forecast soundings
suggest the low level saturation at 2500 ft to persist through
late afternoon so have adjusted to mostly cloudy skies through
most of the day. Also lowered highs about 5-7 degrees to the upper
70s and lower 80s. Will continue to monitor trends, especially
over north central areas where earlier clearing will quickly warm
temps.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 231 AM CDT SAT AUG 29 2015
Early this morning an upper level trough extended from the northern
Great Lakes...southwest across northern MO into eastern KS. The
surface cold front was moving southeast of the CWA. A broad upper
level ridge was located across the west central US.
The upper trough will shear apart with the more amplified northern
branch moving east across the Great Lakes States. The southern
section of the H5 trough will dig south across northeast OK through
the day. The model forecast soundings show wrap around low-level
moisture will advect southeast across northeast and east central KS
this morning. The low clouds should increase towards sunrise across
the eastern half of the CWA. I cannot rule out a few sprinkles but
the stronger ascent for rain showers and thunderstorms will be east
and south of the CWA. The clouds will gradually erode from west to
east across northeast and east central KS through the late morning
and early afternoon hours. Skies will remain clear across the
western counties of the CWA and patchy fog may develop before
sunrise but should mix out by 8 AM. Most areas will become mostly
sunny during the mid afternoon hours, though a few more clouds may
continue across the southeast counties through the afternoon hours.
Highs will be in the lower 80s across most of the CWA. The western
counties will receive more insolation and may reach into the mid 80s
for afternoon highs.
Tonight...The H5 trough digging south-southwest across east central
OK will cause a sfc and 850mb low to develop across central and
eastern OK. Some of the numerical models develop weak isentropic
lift across southeast KS and western MO. The extreme southeast
counties may see a few isolated showers but at this time I will keep
14 pops across the southeast counties of the CWA. Once again some
patchy fog may develop across north central KS by
sunrise...especially if skies remain clear through the night.
Overnight lows will drop to around 60 degrees across the western
counties of the CWA with lower to mid 60s across east central KS.
.LONG TERM...(Sunday THROUGH Friday)
ISSUED AT 231 AM CDT SAT AUG 29 2015
Remnants of upper trough moving through the area tonight will
weaken and leave a vort max in the vicinity of southern MO that
remains nearly stationary through Monday. This feature will
result in scattered clouds and a few showers that could extend
into extreme east central and southeast KS during this time. While
isolated showers aren`t out of the question in our far
southeastern forecast area south of I35, chances are low enough
that I did not include in any products at this time.
Other than the influence of the aforementioned vort max, an upper
ridge axis will extend from the southern Rockies into the Upper
Midwest early next week. From Tuesday through Wednesday, a
shortwave trough will move from the central Rockies to the Upper
Midwest, flattening the ridge axis and producing lift out ahead of
it. Main dynamics and lift with this system will be focused to
our north, but medium range models continue to have continuity in
producing QPF down into northeast KS with the best chance Tuesday
night.
After that, upper ridge builds back in which should keep the
eastern third of KS dry through the rest of the work week.
Pattern is favorable for temperatures to average several degrees
above normal for late August with highs near 90 for most of the
week and lows in the 65 to 70 degree range.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z Sunday MORNING)
ISSUED AT 638 AM CDT SAT AUG 29 2015
MVFR ceilings are expected to move south to TOP/FOE within the hour,
while MHK is varying between VFR/MVFR. Expect MVFR ceilings to hold
on through the late morning before mixing out between 18-19Z. IFR
ceilings are seen by sites near the KS/NE boarder, but confidence
with them reaching this far south is low. After 18-19Z, light winds
and mostly clear skies are forecast the rest of the period.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Bowen
SHORT TERM...Gargan
LONG TERM...GDP
AVIATION...Heller
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
355 PM EDT SAT AUG 29 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 355 PM EDT SAT AUG 29 2015
19Z SFC ANALYSIS SHOWS HIGH PRESSURE EXITING TO THE EAST WHILE A
BROAD AREA OF LOW PRESSURE IS DRIFTING TOWARD THE STATE FROM THE
CENTRAL PLAINS. THE INCREASE IN MOISTURE AND LACK OF A CAP HAVE
ALLOWED A FEW CELLS TO DEVELOP THROUGH WESTERN AND NORTHERN PARTS
OF THE AREA THIS AFTERNOON. SO FAR...THE COVERAGE HAS BEEN FAIRLY
SPARSE AND THAT SHOULD BE THE CASE INTO THE EVENING AS THE
DIURNALLY DRIVEN INSTABILITY WANES. TEMPERATURES ARE IN THE MID
80S AT MOST PLACES WITH DEWPOINTS IN THE MID 60S. UNDER PARTLY
SUNNY SKIES WINDS ARE FROM THE SOUTH TO SOUTHWEST AT AROUND 10
KTS.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM
PORTION OF THE FORECAST. THEY ALL DEPICT A BROAD AND RATHER WEAK
TROUGH OVER THE OHIO AND TENNESSEE VALLEYS WITH SLOW MOVING
BATCHES OF ENERGY CAUGHT OVER THE REGION...STUCK BETWEEN
MARGINALLY HIGHER HEIGHTS TO THE WEST AND SOUTHEAST. GIVEN THE
BROAD AGREEMENT WITH THE MODELS HAVE FAVORED THE HIGHER RESOLUTION
GUIDANCE FROM THE HRRR AND NAM12 FOR WEATHER DETAILS.
SENSIBLE WEATHER WILL FEATURE THE ISOLATED TO SCATTERED SHOWERS
AND THUNDERSTORMS DIMINISHING TOWARD AND AFTER SUNSET WITH PARTLY
CLOUDY SKIES ANTICIPATED THROUGH THE NIGHT. PATCHY VALLEY FOG WILL
AGAIN FORM TOWARDS DAWN WITH A SMALL RIDGE TO VALLEY TEMPERATURE
SPLIT LIKELY SETTING UP. SUNDAY WILL SEE A BETTER CHANCE FOR
CONVECTION THROUGHOUT THE CWA WITH MORE CLOUDS HELPING TO KEEP
TEMPERATURES ABOUT A CATEGORY COOLER...BUT WITH CONDITIONS EQUAL
OR EVEN MORE HUMID THAN TODAY. AGAIN PATCHY FOG AND A MINOR RIDGE
TO VALLEY TEMP SPLIT CAN BE EXPECTED LATER SUNDAY NIGHT INTO
MONDAY MORNING.
STARTED WITH THE SHORTBLEND FOR TEMPERATURES...DEWPOINTS...AND
WINDS THROUGH THE EVENING BEFORE GOING WITH THE SUPERBLEND FOR
THE REST OF THE PERIOD. DID ADJUST THE MIN TEMPERATURES EACH NIGHT
FOR TERRAIN DIFFERENCES. AS FOR POPS...ENDED UP CLOSER TO THE
DRIER MAV NUMBERS THROUGHOUT THE SHORT TERM PERIOD.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 330 PM EDT SAT AUG 29 2015
UPPER LEVEL RIDGING WILL REMAIN IN PLACE ACROSS MUCH OF THE EASTERN
CONUS THROUGHOUT THE EXTENDED. MEANWHILE...BOTH THE REMNANTS OF TS
ERIKA AND A WEAK UPPER LEVEL LOW OVER THE MISSISSIPPI RIVER VALLEY
WILL BE THE FEATURES THAT WILL PREVENT US FROM HAVING A COMPLETELY
DRY AND CLEAR WEEK AHEAD. THE UPPER LEVEL RIDGE WILL BE THE MAIN
PLAYER...KEEPING STABLE AIR ACROSS THE REGION DURING THE OVERNIGHT
HOURS AS THE TEMPERATURES COOL. HOWEVER...DURING THE
DAY...INCREASING TEMPERATURES AND THE ABOVE MENTIONED UPPER LEVEL
TRIGGERS WILL RESULT IN SOME ISL TO SCT SHOWERS AND THUNDERSTORMS
ACROSS THE REGION. OUR BEST CHANCES FOR SEEING PRECIP WILL BE DURING
THE DAY MONDAY AS THE LOW THAT WAS TS ERIKA MOVES FAR ENOUGH WEST TO
IMPACT FAR SE KY. IT WILL QUICKLY TRANSITION TO THE NE
HOWEVER...WITH AN APPROACHING SHORTWAVE AND THE DIMINISHING UPPER
LEVEL LOW OVER THE MISSISSIPPI VALLEY SHIFTING EASTWARD ACROSS KY
BY MID WEEK.
MOST OF THE WINDS THROUGH THIS PERIOD WILL BE FROM THE EAST AT THE
SURFACE...AND FROM THE WSW IN THE MID AND UPPER LEVELS. IN OTHER
WORDS...IT IS NOT VERY FAVORABLE FOR SUSTAINABLE THUNDERSTORM
DEVELOPMENT. NOT GOING TO RULE OUT SOME RUMBLES OF THUNDER...SO DID
KEEP MENTION OF TSRA IN FORECAST...BUT DON/T EXPECT STORMS TO BECOME
VERY TALL OR BE FAST MOVERS. NOT TO MENTION LATEST GFS FORECAST
SOUNDINGS DON/T SHOW LI/S BELOW -5C AND CAPE ABOVE 1500 J/KG /WITH
THE EXCEPTION OF MONDAY/...SO NOTHING TOO CONCERNABLE EXPECTED
THROUGH THE WEEK AT THIS POINT.
THE OVERALL RIDGE PATTERN AND LACK OF WIDESPREAD CLOUD COVER WILL
ALLOW TEMPERATURES TO SLOWLY INCREASE EACH DAY THROUGHOUT THE WEEK.
WHILE HIGH TEMPERATURES ON MONDAY WILL STILL BE CONTAINED IN THE LOW
TO MID 80S...WE COULD SEE UPPER 80S BY TUESDAY...AND POSSIBLY EVEN A
90 DEGREE SPOT OR TWO TO ROUND OUT THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 230 PM EDT SAT AUG 29 2015
ISOLATED CONVECTION WILL BE AROUND THROUGH THE FIRST PART OF THE
EVENING...BUT THE TAF SITES SHOULD BE SPARED. THE NIGHT WILL BE
QUIET WITH JUST SOME LIGHT FOG ANTICIPATED IN THE VALLEYS...
POSSIBLY AFFECTING THE SME AND LOZ TAF SITES. EXPECT MORE CLOUDS A
BIT LOWER DURING THE DAY SUNDAY WITH SCATTERED STORMS ANTICIPATED
FOR THE AFTERNOON. WINDS WILL BE FROM THE SOUTH TO SOUTHWEST
THROUGH THE REST OF THE DAY AND AGAIN ON SUNDAY GENERALLY AT 5 TO
10 KTS WITH SOME HIGHER GUSTS POSSIBLE AT SYM.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
106 PM EDT SAT AUG 29 2015
...UPDATED AVIATION DISCUSSION...
.SHORT TERM (NOW THROUGH SUNDAY)...
ISSUED AT 235 AM EDT SAT AUG 29 2015
EARLY MORNING WATER VAPOR IMAGERY COMBINED WITH 500 MB HEIGHTS
SHOWED A MID LEVEL TROUGH EXTENDING FROM THE CENTRAL PLAINS
NORTHEASTWARD TOWARD EASTERN WISCONSIN...WHILE A BROAD CLOSED LOW
WAS ADVANCING NORTHWARD FROM THE GULF INTO THE DEEP SOUTH. THE LOWER
OHIO VALLEY LIED IN BETWEEN...AS OBSERVED BY IR SATELLITE IMAGERY
WHICH SHOWED MOSTLY CLEAR SKIES AND LIGHT WINDS. DEEPER
MOISTURE...CLOUDY SKIES...AND LIGHT RADAR RETURNS WERE OFF TO THE
NORTHWEST.
THE MAIN FORECAST CONCERN FOR TODAY IS PRECIPITATION CHANCES AS THE
TWO AFOREMENTIONED SYSTEMS TRACK TOWARD EACH OTHER. THE SOUTHERN
SYSTEM WILL DRAW MORE MOISTURE INTO THE AREA...CHARACTERIZED BY
DEWPOINTS APPROACHING THE UPPER 60S TO NEAR 70 THIS AFTERNOON. THE
NORTHERN SYSTEM WILL BEGIN TO WASH OUT AS IT SLOWLY ADVANCES
EASTWARD. OVERALL...DYNAMICS ARE RATHER WEAK WITH THESE SYSTEMS BUT
A WEAKLY OR UNCAPPED ENVIRONMENT ALONG WITH PEAK HEATING GENERATING
POCKETS OF INSTABILITY SHOULD BREAK OUT ISOLATED TO SCATTERED NON
SEVERE SHOWERS AND STORMS.
NEAR TERM HI-RES MODELS SHOW HIGH AGREEMENT SPATIALLY...TEMPORALLY
AND RUN TO RUN WHICH LEADS TO A HIGHER CONFIDENCE FORECAST FOR
TODAY. THE HRRR HAS BEEN VERY CONSISTENT SHOWING ISOLATED
SHOWERS/STORMS BREAKING OUT DURING THE EARLY AFTERNOON HOURS AS
CONVECTIVE TEMPS ARE REACHED. THE NSSL AND SPC WRF SOLUTIONS OFFER
SIMILAR SOLUTIONS AS WELL. THE HIGHEST COVERAGE LOOKS TO BE ALONG A
BOWLING GREEN TO FRANKFORT LINE AND WESTWARD...ALONG THE AXIS OF
GREATER INSTABILITY AND MOISTURE.
MOSTLY SUNNY SKIES THIS MORNING WILL BE REPLACED BY SCATTERED
CUMULUS AS WELL AS MID/HIGH CLOUDS...WHICH SHOULD MAKE FOR A PARTLY
TO MOSTLY CLOUDY AFTERNOON AT TIMES. PLAN ON HIGHS TO TOP OUT IN THE
MID TO BROKEN HIGH CLOUDS WILL OVERSPREAD TAF SITES THIS MORNING...AND LOOK
FOR SOUTHERLY WINDS TO DEVELOP. WITH A WEAKLY UNSTABLE AIR MASS AND
A COUPLE WEATHER SYSTEMS NEARBY...THERE WILL BE A SLIGHT CHANCE OF A
SHOWER/STORM FROM EARLY AFTERNOON THROUGH THE END OF THE TAF PERIOD.
HOWEVER COVERAGE IS NOT EXPECTED TO BE VERY HIGH SO WILL CONTINUE TO
LEAVE OUT OF TAF. MOSTLY CLOUDY SKIES SHOULD LMIITUPPER 80S. THE
INCREASE IN DEWPOINTS WILL MAKE IT FEEL SLIGHTLY MORE MUGGY THAN
RECENT DAYS.
EXPECTING A DROP OFF IN PRECIPITATION THIS EVENING WITH THE LOSS OF
HEATING...THOUGH WILL STILL CARRY A CHANCE THROUGH THE OVERNIGHT
WITH THE WEAK TROUGH OVERHEAD. SUNDAY STILL LOOKS TO BE THE BETTER
DAY FOR PRECIPITATION AS WE`LL HAVE A MORE FAVORABLE ENVIRONMENT AND
OVERALL DYNAMICS. PRECIPITATION COVERAGE STILL LOOKS TO BE
SCATTERED...SO KEPT CHANCES IN THE 30-40 PERCENT RANGE.
.LONG TERM (SUNDAY NIGHT THROUGH FRIDAY)...
ISSUED AT 300 AM EDT SAT AUG 29 2015
MONDAY - WEDNESDAY...
A WEAK UPPER LOW NEAR THE OHIO VALLEY MAY PROVIDE ENOUGH SUPPORT FOR
ISLD SHOWERS/STORMS MAINLY ALONG AND EAST OF I-65 SUNDAY NIGHT AND
MONDAY. THE GFS IS MOST OPTIMISTIC WITH THIS CONVECTION AND EVEN
THIS NOTORIOUSLY WET MODEL ISN`T SHOWING MUCH PRECIP.
TUESDAY LOOKS TO BE DRY WITH THE NEXT CHANCE FOR SHOWERS/STORMS
ARRIVING FOR WED. MID RANGE MODELS ARE DIFFERENT IN DEPICTING THE
MAIN SOURCE FOR FORCING/MOISTURE. THE GFS INDICATES THE REMNANTS OF
T.S. ERIKA WILL BE THE CAUSE WHILE THE ECMWF SUGGESTS A NORTHERN
STREAM TROUGH WILL BE THE CAUSE. EITHER WAY WILL CARRY 20-30% POPS
FOR WED.
TEMPS FOR EARLY TO MID WEEK WILL BE ON THE INCREASE BACK TO SEASONAL
NORMS WITH HIGHS RANGING MAINLY THE MID TO UPPER 80S WITH A FEW
LOCATIONS NEAR 90 TUES/WED.
THURSDAY - FRIDAY...
LONG RANGE MODELS AGREE THAT A STRONG UPPER RIDGE AXIS WILL BUILD
INTO PORTIONS OF THE PLAINS/MIDWEST. THICKNESSES WILL INCREASE OVER
THE OHIO VALLEY AS A RESULT BRINGING TEMPS SLIGHTLY ABOVE NORMAL FOR
THE LATTER HALF OF THE WEEK (UPPER 80S/LOWER 90S FOR HIGHS).
ALTHOUGH A CLEAR TRIGGER IS NOT APPARENT, SOME LONG RANGE SIGNALS
SUGGEST A DIRTY RIDGE WITH SUBTLE WAVES MAY CAUSE MAINLY DIURNAL
CONVECTION PEAKING DURING THE AFTERNOON/EVENING HOURS BOTH
THURS/FRI. THUS WILL HAVE LOW POPS BOTH OF THESE DAYS.
&&
.AVIATION (18Z TAF UPDATE)...
ISSUED AT 105 PM EDT SAT AUG 29 2015
ISOLATED TO WIDELY SCATTERED SHOWERS HAVE DEVELOPED IN AN UNSTABLE
AIRMASS THIS AFTERNOON. EXPECT COVERAGE TO INCREASE SLIGHTLY ALONG
WITH A FEW T-STORMS AS WE GO THROUGH THE AFTERNOON/EARLY EVENING
HOURS. ANY STORM WILL BE CAPABLE FOR GUSTY WINDS AND BRIEF HEAVY
RAINFALL. WITH COVERAGE ONLY EXPECTED TO BE 30% DURING PEAK HEATING,
WILL CONTINUE TO ONLY MENTION VCTS, AND AMEND IF A T-STORM OR SHOWER
LOOKS TO IMPACT VISIBILITIES AT A TERMINAL. EXPECT COVERAGE TO
DIMINISH AROUND 6-7 PM EDT WITH THE LOSS OF HEATING AND WITH DRIER
AIR EVIDENT ON WATER VAPOR IMAGERY MOVING IN FROM THE SW. LEX MAY
HOLD ON AN HOUR OR TWO LONGER BEING FURTHER EAST.
OTHERWISE, EXPECT VFR WITH SCT-BKN SKY COVER IN THE 3-4 K FT RANGE
THIS AFTERNOON AND A STEADY SSW WIND. SHOULD BE RELAIVELY QUIET
OVERNIGHT WITH LIGHT AND VARIABLE WINDS. PERHAPS SOME BRIEF MVFR VIS
AT BWG IN THE MORE MOIST AIRMASS, BUT MID AND UPPER CLOUDS COULD BE
A LIMITING FACTOR. EXPECTING A REPEAT OF CONDITIONS ON SUNDAY
SIMILAR TO TODAY.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
SHORT TERM........ZBT
LONG TERM.........AMS
AVIATION..........BJS
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1115 AM EDT SAT AUG 29 2015
.UPDATE...
ISSUED AT 1115 AM EDT SAT AUG 29 2015
14Z SFC ANALYSIS SHOWS HIGH PRESSURE RETREATING OFF TO THE EAST
WHILE A BROAD AREA OF LOW PRESSURE IS MOVING THROUGH THE PLAINS
STATES. UNDER PARTLY CLOUDY SKIES TEMPERATURES HAVE RISEN INTO THE
MID AND UPPER 70S FOR MOST OF THE CWA ALONG WITH INCREASES IN THE
DEWPOINTS TO THE MID AND UPPER 60S. MEANWHILE...WINDS ARE
RESPONDING TO THE EXIT OF THE HIGH TURNING TO THE SOUTH AND
SOUTHWEST AT 5 TO 10 KTS. THE DEPARTING HIGH HAS WORKED TO KEEP
THE WEATHER QUIET THROUGH KENTUCKY FOR MUCH OF THE PAST WEEK BUT
IS LOSING ITS HOLD ON THE AREA. AS SUCH...MOISTURE AND WARMTH WILL
BUILD THROUGH EASTERN KENTUCKY TODAY WITH A FEW POCKETS OF
CONVECTION POSSIBLE BY LATE AFTERNOON...MAINLY OVER WESTERN PARTS
OF THE CWA. THE LATEST HRRR IS ON BOARD WITH THIS...BUT ALSO
TRIES TO DEVELOP SOME OVER THE FAR SOUTHEAST...THAT SEEMS TOO
AGGRESSIVE SO WILL KEEP POPS SUB 14 PERCENT EAST OF INTERSTATE 75
THIS AFTERNOON. HAVE UPDATED THE GRIDS MAINLY TO ADD IN SOME OF
THE LATEST SHORTBLEND GUIDANCE ALONG WITH THE CURRENT OBS AND
TRENDS. THESE GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS
ALONG WITH AN UPDATED SET OF ZONES...DROPPING THE MENTION OF
MORNING FOG...TO FOLLOW.
UPDATE ISSUED AT 744 AM EDT SAT AUG 29 2015
FRESHENED UP THE HOURLY TEMPERATURES...DEW POINTS...AND SKY COVER
TO MATCH UP WITH THE LATEST TRENDS IN OBSERVATIONS...OTHERWISE THE
FORECAST REMAINS ON TRACK.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 336 AM EDT SAT AUG 29 2015
SURFACE HIGH PRESSURE HAS SHIFTED OFF TO THE EASTERN SEABOARD...
WITH SURFACE WINDS BECOMING MORE SOUTHEASTERLY ACROSS EASTERN
KENTUCKY. MOISTURE HAS BEEN ON THE INCREASE...WITH HIGHER BASED CU
DEVELOPING OVERNIGHT AND ADVECTING IN FROM THE SOUTHWEST.
TEMPERATURES ACROSS THE AREA RANGE FROM THE LOWER 60S IN THE
VALLEYS...TO THE UPPER 60S ON THE RIDGETOPS. ALOFT...A SHORT WAVE
TROUGH IS MOVING INTO THE GREAT LAKES/OHIO VALLEY REGION...WITHIN
A POSITIVELY TILTED TROUGH STRUNG OUT BACK TOWARDS THE OKLAHOMA
PANHANDLE. AN UPPER LEVEL LOW ALSO CONTINUES TO CHURN ACROSS GULF
COAST STATES.
MOISTURE WILL BE ON THE INCREASE TODAY AS THE TROUGH GRADUALLY
MOVES FURTHER EAST. HAVE MAINTAINED SLIGHT CHANCE POPS IN THE
WEST...WHERE THERE IS A BETTER CHANCE OF BREAKING THE CAP. FURTHER
EAST...IT APPEARS THE CAP WILL BE STRONG ENOUGH TO KEEP MOST
CONVECTION AT BAY...BESIDES A STRAY SHOWER OR STORM. HIGHS TODAY
WILL TOP OUT IN THE MID 80S...GENERALLY A FEW DEGREES WARMER
COMPARED TO YESTERDAY.
THE TROUGH WILL CONTINUE TO DAMPEN AS IT HEADS ACROSS THE OHIO
AND TENNESSEE VALLEYS THROUGH SUNDAY...HOWEVER THE GULF COAST
UPPER LEVEL WILL ALSO GET PULLED NORTH...HELPING TO REINFORCE AT
LEAST A WEAKER CAP ENVIRONMENT. AS SUCH...EXPECT MORE SCATTERED
CONVECTIVE COVERAGE ON SUNDAY. THICKER CLOUDS WILL KEEP THE HIGHS
CONFINED TO THE LOWER 80S FOR MOST LOCATIONS.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 356 AM EDT SAT AUG 29 2015
THE UPPER LEVEL PATTERN OVER THE OHIO VALLEY THROUGH THE EXTENDED
WILL FEATURE A WEAKENING AND SHIFTING UPPER LEVEL RIDGE. IT WILL
SHIFT TOWARDS THE EAST AND FURTHER NORTH AS IT SETS UP OVER THE
UPPER GREAT LAKES AND INTO THE NEW ENGLAND REGION AND REMAINS IN
PLACE THROUGH THE ENTIRE EXTENDED. DURING THIS TIME...UNDERNEATH
THE RIDGE...A FEW LOW CENTERS...INCLUDING THE REMNANTS OF TS ERIKA
WILL DRIVE MUCH OF EASTERN KENTUCKYS WEATHER CUT OFF FROM THE MAIN
UPPER LEVEL FLOW. DURING THIS TIME...MUCH OF THE ACTIVITY REMAINS
OVER THE SOUTH CENTRAL AND SOUTHEASTERN CONUS WITH AN INFLUX
SOUTHERLY MOIST FLOW CONTINUING THROUGH THE PERIOD AS WELL. PIN
POINTING THESE FEATURES IN THIS WEAK FLOW WILL PROVE VERY
DIFFICULT.
CLOSER TO THE SURFACE...WITH THE PATTERN DRIVEN BY SEVERAL WEAK
LOW CENTERS...SOUTHERLY MOIST AND UNSTABLE FLOW AND WEAK UPPER
LEVEL FLOW...WOULD EXPECT A DIURNAL TREND TO THE SHOWER AND
THUNDERSTORM CHANCES FOR THE EXTENDED. THIS THOUGHT PROCESS IS
SUPPORTED BY THE SHEAR LACK OF ANY FORCING. HOWEVER...MODEL
SOUNDINGS WOULD ALSO SUGGEST WITH THE LACK OF ANY GOOD CAP AS
WELL. WITH THIS IN MIND...IT IS QUITE DIFFICULT TO PIN POINT A DRY
AFTERNOON TO THE EXTENDED AS WELL. DID GO BELOW THE SUPER BLEND IN
MOST DAYS KEEPING SLIGHT CHANCE TO VERY LOW CHANCE POPS THROUGH
THE PERIOD AND NIXING ANY NOCTURNAL PRECIP. IN SHORT...THE VERY
WARM...MUGGY...AND UNSTABLE DAYS OF SUMMER ARE RETURNING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 744 AM EDT SAT AUG 29 2015
MVFR OR WORSE FOG WILL BURN OFF BY AROUND 13Z...THEN EXPECT VFR
CONDITIONS TO PREVAIL THEREAFTER. SOME ISOLATED CONVECTION WILL
THREATEN DURING THE DAY...HOWEVER WILL CONTINUE TO LEAVE OUT A
MENTION AT THE TAF SITES FOR NOW GIVEN THE EXPECTED LIMITED AREAL
COVERAGE. WINDS WILL ENGAGE OUT OF THE SSW AT AROUND 5 KTS DURING
THE DAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GEOGERIAN
LONG TERM...SHALLENBERGER
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
629 AM EDT SAT AUG 29 2015
...UPDATED AVIATION DISCUSSION...
.SHORT TERM (NOW THROUGH SUNDAY)...
ISSUED AT 235 AM EDT SAT AUG 29 2015
EARLY MORNING WATER VAPOR IMAGERY COMBINED WITH 500 MB HEIGHTS
SHOWED A MID LEVEL TROUGH EXTENDING FROM THE CENTRAL PLAINS
NORTHEASTWARD TOWARD EASTERN WISCONSIN...WHILE A BROAD CLOSED LOW
WAS ADVANCING NORTHWARD FROM THE GULF INTO THE DEEP SOUTH. THE LOWER
OHIO VALLEY LIED IN BETWEEN...AS OBSERVED BY IR SATELLITE IMAGERY
WHICH SHOWED MOSTLY CLEAR SKIES AND LIGHT WINDS. DEEPER
MOISTURE...CLOUDY SKIES...AND LIGHT RADAR RETURNS WERE OFF TO THE
NORTHWEST.
THE MAIN FORECAST CONCERN FOR TODAY IS PRECIPITATION CHANCES AS THE
TWO AFOREMENTIONED SYSTEMS TRACK TOWARD EACH OTHER. THE SOUTHERN
SYSTEM WILL DRAW MORE MOISTURE INTO THE AREA...CHARACTERIZED BY
DEWPOINTS APPROACHING THE UPPER 60S TO NEAR 70 THIS AFTERNOON. THE
NORTHERN SYSTEM WILL BEGIN TO WASH OUT AS IT SLOWLY ADVANCES
EASTWARD. OVERALL...DYNAMICS ARE RATHER WEAK WITH THESE SYSTEMS BUT
A WEAKLY OR UNCAPPED ENVIRONMENT ALONG WITH PEAK HEATING GENERATING
POCKETS OF INSTABILITY SHOULD BREAK OUT ISOLATED TO SCATTERED NON
SEVERE SHOWERS AND STORMS.
NEAR TERM HI-RES MODELS SHOW HIGH AGREEMENT SPATIALLY...TEMPORALLY
AND RUN TO RUN WHICH LEADS TO A HIGHER CONFIDENCE FORECAST FOR
TODAY. THE HRRR HAS BEEN VERY CONSISTENT SHOWING ISOLATED
SHOWERS/STORMS BREAKING OUT DURING THE EARLY AFTERNOON HOURS AS
CONVECTIVE TEMPS ARE REACHED. THE NSSL AND SPC WRF SOLUTIONS OFFER
SIMILAR SOLUTIONS AS WELL. THE HIGHEST COVERAGE LOOKS TO BE ALONG A
BOWLING GREEN TO FRANKFORT LINE AND WESTWARD...ALONG THE AXIS OF
GREATER INSTABILITY AND MOISTURE.
MOSTLY SUNNY SKIES THIS MORNING WILL BE REPLACED BY SCATTERED
CUMULUS AS WELL AS MID/HIGH CLOUDS...WHICH SHOULD MAKE FOR A PARTLY
TO MOSTLY CLOUDY AFTERNOON AT TIMES. PLAN ON HIGHS TO TOP OUT IN THE
MID TO UPPER 80S. THE INCREASE IN DEWPOINTS WILL MAKE IT FEEL
SLIGHTLY MORE MUGGY THAN RECENT DAYS.
EXPECTING A DROP OFF IN PRECIPITATION THIS EVENING WITH THE LOSS OF
HEATING...THOUGH WILL STILL CARRY A CHANCE THROUGH THE OVERNIGHT
WITH THE WEAK TROUGH OVERHEAD. SUNDAY STILL LOOKS TO BE THE BETTER
DAY FOR PRECIPITATION AS WE`LL HAVE A MORE FAVORABLE ENVIRONMENT AND
OVERALL DYNAMICS. PRECIPITATION COVERAGE STILL LOOKS TO BE
SCATTERED...SO KEPT CHANCES IN THE 30-40 PERCENT RANGE.
.LONG TERM (SUNDAY NIGHT THROUGH FRIDAY)...
ISSUED AT 300 AM EDT SAT AUG 29 2015
MONDAY - WEDNESDAY...
A WEAK UPPER LOW NEAR THE OHIO VALLEY MAY PROVIDE ENOUGH SUPPORT FOR
ISLD SHOWERS/STORMS MAINLY ALONG AND EAST OF I-65 SUNDAY NIGHT AND
MONDAY. THE GFS IS MOST OPTIMISTIC WITH THIS CONVECTION AND EVEN
THIS NOTORIOUSLY WET MODEL ISN`T SHOWING MUCH PRECIP.
TUESDAY LOOKS TO BE DRY WITH THE NEXT CHANCE FOR SHOWERS/STORMS
ARRIVING FOR WED. MID RANGE MODELS ARE DIFFERENT IN DEPICTING THE
MAIN SOURCE FOR FORCING/MOISTURE. THE GFS INDICATES THE REMNANTS OF
T.S. ERIKA WILL BE THE CAUSE WHILE THE ECMWF SUGGESTS A NORTHERN
STREAM TROUGH WILL BE THE CAUSE. EITHER WAY WILL CARRY 20-30% POPS
FOR WED.
TEMPS FOR EARLY TO MID WEEK WILL BE ON THE INCREASE BACK TO SEASONAL
NORMS WITH HIGHS RANGING MAINLY THE MID TO UPPER 80S WITH A FEW
LOCATIONS NEAR 90 TUES/WED.
THURSDAY - FRIDAY...
LONG RANGE MODELS AGREE THAT A STRONG UPPER RIDGE AXIS WILL BUILD
INTO PORTIONS OF THE PLAINS/MIDWEST. THICKNESSES WILL INCREASE OVER
THE OHIO VALLEY AS A RESULT BRINGING TEMPS SLIGHTLY ABOVE NORMAL FOR
THE LATTER HALF OF THE WEEK (UPPER 80S/LOWER 90S FOR HIGHS).
ALTHOUGH A CLEAR TRIGGER IS NOT APPARENT, SOME LONG RANGE SIGNALS
SUGGEST A DIRTY RIDGE WITH SUBTLE WAVES MAY CAUSE MAINLY DIURNAL
CONVECTION PEAKING DURING THE AFTERNOON/EVENING HOURS BOTH
THURS/FRI. THUS WILL HAVE LOW POPS BOTH OF THESE DAYS.
&&
.AVIATION (12Z TAF UPDATE)...
ISSUED AT 629 AM EDT SAT AUG 29 2015
BROKEN HIGH CLOUDS WILL OVERSPREAD TAF SITES THIS MORNING...AND LOOK
FOR SOUTHERLY WINDS TO DEVELOP. WITH A WEAKLY UNSTABLE AIR MASS AND
A COUPLE WEATHER SYSTEMS NEARBY...THERE WILL BE A SLIGHT CHANCE OF A
SHOWER/STORM FROM EARLY AFTERNOON THROUGH THE END OF THE TAF PERIOD.
HOWEVER COVERAGE IS NOT EXPECTED TO BE VERY HIGH SO WILL CONTINUE TO
LEAVE OUT OF TAF. MOSTLY CLOUDY SKIES SHOULD LMIIT
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
SHORT TERM........ZBT
LONG TERM.........AMS
AVIATION..........ZBT
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
306 AM EDT SAT AUG 29 2015
.SHORT TERM (NOW THROUGH SUNDAY)...
ISSUED AT 235 AM EDT SAT AUG 29 2015
EARLY MORNING WATER VAPOR IMAGERY COMBINED WITH 500 MB HEIGHTS
SHOWED A MID LEVEL TROUGH EXTENDING FROM THE CENTRAL PLAINS
NORTHEASTWARD TOWARD EASTERN WISCONSIN...WHILE A BROAD CLOSED LOW
WAS ADVANCING NORTHWARD FROM THE GULF INTO THE DEEP SOUTH. THE
LOWER OHIO VALLEY LIED IN BETWEEN...AS OBSERVED BY IR SATELLITE
IMAGERY WHICH SHOWED MOSTLY CLEAR SKIES AND LIGHT WINDS. DEEPER
MOISTURE...CLOUDY SKIES...AND LIGHT RADAR RETURNS WERE OFF TO THE
NORTHWEST.
THE MAIN FORECAST CONCERN FOR TODAY IS PRECIPITATION CHANCES AS THE
TWO AFOREMENTIONED SYSTEMS TRACK TOWARD EACH OTHER. THE SOUTHERN
SYSTEM WILL DRAW MORE MOISTURE INTO THE AREA...CHARACTERIZED BY
DEWPOINTS APPROACHING THE UPPER 60S TO NEAR 70 THIS AFTERNOON. THE
NORTHERN SYSTEM WILL BEGIN TO WASH OUT AS IT SLOWLY ADVANCES
EASTWARD. OVERALL...DYNAMICS ARE RATHER WEAK WITH THESE SYSTEMS BUT
A WEAKLY OR UNCAPPED ENVIRONMENT ALONG WITH PEAK HEATING GENERATING
POCKETS OF INSTABILITY SHOULD BREAK OUT ISOLATED TO SCATTERED NON
SEVERE SHOWERS AND STORMS.
NEAR TERM HI-RES MODELS SHOW HIGH AGREEMENT SPATIALLY...TEMPORALLY
AND RUN TO RUN WHICH LEADS TO A HIGHER CONFIDENCE FORECAST FOR
TODAY. THE HRRR HAS BEEN VERY CONSISTENT SHOWING ISOLATED
SHOWERS/STORMS BREAKING OUT DURING THE EARLY AFTERNOON HOURS AS
CONVECTIVE TEMPS ARE REACHED. THE NSSL AND SPC WRF SOLUTIONS OFFER
SIMILAR SOLUTIONS AS WELL. THE HIGHEST COVERAGE LOOKS TO BE ALONG A
BOWLING GREEN TO FRANKFORT LINE AND WESTWARD...ALONG THE AXIS OF
GREATER INSTABILITY AND MOISTURE.
MOSTLY SUNNY SKIES THIS MORNING WILL BE REPLACED BY SCATTERED
CUMULUS AS WELL AS MID/HIGH CLOUDS...WHICH SHOULD MAKE FOR A PARTLY
TO MOSTLY CLOUDY AFTERNOON AT TIMES. PLAN ON HIGHS TO TOP OUT IN THE
MID TO UPPER 80S. THE INCREASE IN DEWPOINTS WILL MAKE IT FEEL
SLIGHTLY MORE MUGGY THAN RECENT DAYS.
EXPECTING A DROP OFF IN PRECIPITATION THIS EVENING WITH THE LOSS OF
HEATING...THOUGH WILL STILL CARRY A CHANCE THROUGH THE OVERNIGHT
WITH THE WEAK TROUGH OVERHEAD. SUNDAY STILL LOOKS TO BE THE BETTER
DAY FOR PRECIPITATION AS WE`LL HAVE A MORE FAVORABLE ENVIRONMENT AND
OVERALL DYNAMICS. PRECIPITATION COVERAGE STILL LOOKS TO BE
SCATTERED...SO KEPT CHANCES IN THE 30-40 PERCENT RANGE.
.LONG TERM (SUNDAY NIGHT THROUGH FRIDAY)...
ISSUED AT 300 AM EDT SAT AUG 29 2015
MONDAY - WEDNESDAY...
A WEAK UPPER LOW NEAR THE OHIO VALLEY MAY PROVIDE ENOUGH SUPPORT FOR
ISLD SHOWERS/STORMS MAINLY ALONG AND EAST OF I-65 SUNDAY NIGHT AND
MONDAY. THE GFS IS MOST OPTIMISTIC WITH THIS CONVECTION AND EVEN
THIS NOTORIOUSLY WET MODEL ISN`T SHOWING MUCH PRECIP.
TUESDAY LOOKS TO BE DRY WITH THE NEXT CHANCE FOR SHOWERS/STORMS
ARRIVING FOR WED. MID RANGE MODELS ARE DIFFERENT IN DEPICTING THE
MAIN SOURCE FOR FORCING/MOISTURE. THE GFS INDICATES THE REMNANTS OF
T.S. ERIKA WILL BE THE CAUSE WHILE THE ECMWF SUGGESTS A NORTHERN
STREAM TROUGH WILL BE THE CAUSE. EITHER WAY WILL CARRY 20-30% POPS
FOR WED.
TEMPS FOR EARLY TO MID WEEK WILL BE ON THE INCREASE BACK TO SEASONAL
NORMS WITH HIGHS RANGING MAINLY THE MID TO UPPER 80S WITH A FEW
LOCATIONS NEAR 90 TUES/WED.
THURSDAY - FRIDAY...
LONG RANGE MODELS AGREE THAT A STRONG UPPER RIDGE AXIS WILL BUILD
INTO PORTIONS OF THE PLAINS/MIDWEST. THICKNESSES WILL INCREASE OVER
THE OHIO VALLEY AS A RESULT BRINGING TEMPS SLIGHTLY ABOVE NORMAL FOR
THE LATTER HALF OF THE WEEK (UPPER 80S/LOWER 90S FOR HIGHS).
ALTHOUGH A CLEAR TRIGGER IS NOT APPARENT, SOME LONG RANGE SIGNALS
SUGGEST A DIRTY RIDGE WITH SUBTLE WAVES MAY CAUSE MAINLY DIURNAL
CONVECTION PEAKING DURING THE AFTERNOON/EVENING HOURS BOTH
THURS/FRI. THUS WILL HAVE LOW POPS BOTH OF THESE DAYS.
&&
.AVIATION (06Z TAF UPDATE)...
ISSUED AT 104 AM EDT SAT AUG 29 2015
A LIGHT WIND COMBINED WITH PASSING HIGH CLOUDS SHOULD LIMIT FOG
POTENTIAL AT BWG/LEX THROUGH EARLY THIS MORNING. OTHERWISE...PLAN ON
VFR CONDITIONS AT ALL SITES AS SOUTHERLY WINDS DEVELOP BY MID-
MORNING ALONG WITH A SCATTERED CU FIELD WITH BASES 4-5 KFT. THERE
ARE SIGNALS FOR ISOLATED TO SCATTERED SHOWERS OR A STORM
DEVELOPING BY 17-18Z...LASTING THROUGH ABOUT 23-00Z.
THOUGH...EXPECTING LOW COVERAGE WHICH PRECLUDES MENTIONING IN THE
TAF FOR NOW. WINDS WILL REMAIN SOUTHERLY THROUGH THE END OF THE
TAF PERIOD WITH PASSING SCATTERED/BROKEN HIGH CLOUDS.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
SHORT TERM........ZBT
LONG TERM.........AMS
AVIATION..........ZBT
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
945 PM CDT SUN AUG 30 2015
.UPDATE...THE FEW SHOWERS THAT WERE OVER EAST TEXAS THIS EVENING
HAVE DISSIPATED. WHILE 00Z LCH SOUNDING SHOWS A GOOD DRY AIR
LAYER...LATEST HRRR IS STILL HINTING AT SHOWER DEVELOPMENT OVER
THE COAST AND NEARSHORE WATERS LATE TONIGHT.
WILL TWEAK TEMPS FOR TONIGHT. NO OTHER CHANGES AT THIS MOMENT.
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 69 93 72 93 / 10 10 10 20
LCH 72 89 74 89 / 10 30 20 30
LFT 72 91 74 92 / 10 30 10 20
BPT 72 90 75 89 / 10 30 20 40
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
PUBLIC...04
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1042 PM EDT SUN AUG 30 2015
.SYNOPSIS...
A WEAK COLD FRONT WILL APPROACH NORTHWEST MAINE LATER
TONIGHT...THEN CROSS THE REGION MONDAY. HIGH PRESSURE WILL BUILD
ACROSS THE REGION TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
10PM UPDATE: DID BUMP TEMPS DOWN A BIT BASED ON CURRENT
CONDITIONS; CHANGES WERE MOSTLY THROUGH 06Z, BUT DID LOWER TEMPS A
BIT IN SOME SPOTS - MAINLY THE NRN CWA. MAINTAINED THE PREVIOUS
POPS THROUGH MONDAY, AS 00Z NAM AND HRRR GUIDANCE MAINTAINS THE
IDEA OF ANY RAIN HOLDING OFF UNTIL AFTER 12Z, THEN EXITING TO THE
EAST BY AROUND 21Z OR PERHAPS A BIT SOONER.
ORIGINAL DISCUSSION:
A WEAK COLD FRONT WILL APPROACH NORTHWEST MAINE LATER TONIGHT.
PARTLY CLOUDY SKIES WILL OCCUR ACROSS NORTHERN MAINE EARLY
TONIGHT...WITH INCREASING CLOUDS LATE IN ADVANCE OF THE
APPROACHING FRONT. ACROSS DOWNEAST AREAS...EXPECT PARTLY CLOUDY
SKIES EARLY TONIGHT WITH MOSTLY CLEAR SKIES OVERNIGHT. THE COLD
FRONT WILL CROSS THE REGION MONDAY...WITH AN UPPER LEVEL
DISTURBANCE TRACKING NORTH OF MAINE. WILL HAVE A CHANCE OF
SHOWERS/THUNDERSTORMS ACROSS NORTHERN AND CENTRAL PORTIONS OF THE
FORECAST AREA MONDAY...WITH THE BETTER CHANCES ACROSS NORTHERN
AREAS NEAREST THE UPPER LEVEL DISTURBANCE WHICH WILL PROVIDE
ADDITIONAL SUPPORT. OTHERWISE...EXPECT MOSTLY/PARTLY CLOUDY SKIES
ACROSS NORTHERN AND CENTRAL AREAS MONDAY. EXPECT PARTLY/MOSTLY
SUNNY SKIES DOWNEAST MONDAY. LOW TEMPERATURES TONIGHT WILL RANGE
FROM THE UPPER 50S TO AROUND 60 ACROSS THE FORECAST AREA. HIGH
TEMPERATURES MONDAY WILL RANGE FROM THE UPPER 70S TO AROUND 80
NORTH...TO THE LOWER TO MID 80S DOWNEAST.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
HIGH PRESSURE ALOFT OVER THE EASTERN U.S. WILL DOMINATE THE WEATHER
PATTERN INTO MID WEEK. EASTERN MAINE WILL BE IN NORTHWEST FLOW ON
THE PERIPHERY OF THIS RIDGE AXIS.
EXPECT WELL ABOVE NORMAL TEMPERATURES WITH SUMMER HOLDING ON INTO
EARLY SEPTEMBER. A WEAK DISTURBANCE MOVING THROUGH THE NORTHWEST
FLOW ALOFT MAY TRIGGER SHOWERS AND THUNDERSTORMS ON WEDNESDAY ACROSS
THE CROWN OF MAINE.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
MEDIUM RANGE MODELS ARE DEPICTING A WONDERFUL LABOR DAY WEEKEND WITH
MUCH ABOVE NORMAL TEMPERATURES AND DRY WEATHER.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
NEAR TERM: 10PM UPDATE: NO MAJOR CHANGES MADE. 00Z TAFS REMAIN ON
TRACK WITH VFR CONDITIONS IN ALL LOCATIONS AND EXPECTED TO PERSIST
THRU SUNRISE.
ORIGINAL DISCUSSION:
GENERALLY EXPECT VFR CONDITIONS ACROSS THE REGION
TONIGHT THROUGH MONDAY. HOWEVER...OCCASIONAL MVFR CONDITIONS COULD
OCCUR WITH ANY SHOWERS OR THUNDERSTORMS ACROSS NORTHERN AND
CENTRAL AREAS MONDAY AFTERNOON.
SHORT TERM: MVFR CEILINGS AND VSBYS WILL BE POSSIBLE AT NORTHERN
TAF SITES /FVE CAR PQI/ ON WEDNESDAY IN SHOWERS AND THUNDERSTORMS.
&&
.MARINE...
NEAR TERM: WINDS/SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY
LEVELS TONIGHT THROUGH MONDAY.
SHORT TERM: NO HEADLINES ARE EXPECTED DURING THIS TIME PERIOD.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...KREDENSOR/NORCROSS
SHORT TERM...OKULSKI
LONG TERM...OKULSKI
AVIATION...KREDENSOR/NORCROSS/OKULSKI
MARINE...KREDENSOR/NORCROSS/OKULSKI
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1142 PM EDT SUN AUG 30 2015
.AVIATION...
AREA OBSERVATIONS HAVE BEGUN TO FALL TO 1/4 MILE VISIBILITY UNDER
GOOD RADIATING CONDITIONS AND ELEVATED SURFACE DEWPOINTS. INCREASING
CIRRUS DEBRIS FROM THE NORTHWEST CASTS SOME UNCERTAINTY ON THE
SCENARIO, BUT EXPECTATION IS FOR OTHER LOCATIONS TO FOLLOW. HAVE
TRENDED VSBYS DOWNWARD AT THE AIRFIELDS ACCORDINGLY, WITH RAPID
IMPROVEMENT EXPECTED BY 14-15Z. HIGH BASED CU POTENTIAL DURING PEAK
HEATING MONDAY, BUT COVERAGE SHOULD BE LIMITED GIVEN DRIER AIRMASS
AND SOME INHIBITION TO HEATING BY HIGH CLOUDS.
//DTW THRESHOLD PROBABILITIES...
* MEDIUM FOR VSBY AOB 1/2 MILE 09-12Z.
&&
.PREV DISCUSSION...ISSUED 1101 PM EDT SUN AUG 30 2015
UPDATE...
CLEAR SKIES, CALM WINDS, AND DEWPOINTS SOLIDLY IN THE 60S ARE GIVING
WAY TO INCREASINGLY WIDESPREAD DENSE FOG AT 03Z, MAINLY NORTH OF
M59. IN THE IMMEDIATE DETROIT AREA, LINGERING CLOUDS AND SLOW
COOLING FROM WARMER DAYTIME TEMPS ARE DELAYING ONSET. WHEN ALL IS
SAID AND DONE, HOWEVER, EXPECT THAT ALL COUNTIES WILL SEE A
NOTEWORTHY COMPONENT OF DENSE FOG WORTHY OF AN ADVISORY. A DENSE FOG
ADVISORY IS THEREFORE FORTHCOMING FOR THE I-69 COUNTIES NORTH VALID
IMMEDIATELY. SEEING AS THOUGH SITES SUCH AS ADG, DTW, AND ARB HAVE
YET TO DIP BELOW 1SM (6SM IN THE CASE OF DTW) WILL START THE
REMAINDER OF COUNTIES AT 06Z WITH THE UNDERSTANDING THAT THERE MAY
YET BE SOME FURTHER DELAY IN URBAN CORRIDORS.
PREV DISCUSSION...ISSUED 353 PM EDT SUN AUG 30 2015
SHORT TERM... AFTERNOON AND TONIGHT
MID AFTERNOON MESOANALYSIS INDICATES LOWEST 100 MB MLCAPE IN THE
1000-1500 J/KG RANGE FROM THE OHIO BORDER TO ABOUT THE I-96/696
CORRIDOR. THE RADAR TREND HAS BEEN RELATIVELY SOFT GIVEN THE
INSTABILITY SUGGESTING EITHER DAYTIME HEATING NEEDS A LITTLE MORE
TIME OR THAT MID LEVEL SUBSIDENCE IS SUFFICIENT TO CAP DEEP
CONVECTION. MOST RECENT RAP MODEL SOUNDINGS SUPPORT THE LATTER WITH
THE DEPICTION OF SURFACE BASED PARCELS JUST BARELY CLEARING THE
DEEPENING 700-500 MB WARM/STABLE LAYER. AT THE SAME TIME...THE
NEWEST MESOSCALE MODELS ALLOWING EXPLICIT CONVECTION PRODUCE
SCATTERED COVERAGE OF SHOWERS WITH AN ISOLATED THUNDERSTORM DURING
PEAK HEATING FROM LATE AFTERNOON THROUGH EARLY EVENING. THE MOST
PRUDENT APPROACH IS TO ALLOW FOR AN ISOLATED THUNDERSTORM
CONSIDERING A WIND HAZARD IS IN PLAY CONDITIONAL ON STORM
DEVELOPMENT. WV SATELLITE IMAGERY CONTINUES TO SUPPORT MODEL
SOUNDINGS THAT SHOW VERY DRY AIR CENTERED AROUND 500 MB. THE DRY AIR
IS SYMPTOMATIC OF THE LARGER SCALE SUBSIDENCE OCCURRING THROUGH THE
MID LEVELS THAT IS INHIBITING CONVECTION IN THE FIRST PLACE...BUT
WHICH ALSO COULD PROVIDE STRONG NEGATIVE BUOYANCY POTENTIAL SHOULD
INSTABILITY BECOME ADEQUATE FOR DEEP CONVECTION.
POINTS NORTH OF THE I-69 CORRIDOR WILL BE DRY BUT CLOUDY DURING THE
LATE AFTERNOON AND EVENING...AND ANY SHOWERS/STORMS THAT ARE ABLE TO
FORM SOUTH OF THAT LINE WILL QUICKLY DISSIPATE WITH THE LOSS OF
SURFACE HEATING BY MID EVENING. THAT WILL LEAVE A CLEARING TREND TO
OCCUR THROUGH THE OVERNIGHT AS SURFACE HIGH PRESSURE BECOMES RE-
ESTABLISHED OVER LOWER MICHIGAN. THE NORTHERN FRINGES OF THE SURFACE
HIGH REMAINS SET TO ESTABLISH AREAS OF FOG IN SE MICHIGAN TOWARD
SUNRISE AS MIN TEMPS SETTLE IN THE LOWER TO MID 60S. PROJECTED MIN
TEMPS ARE ABOUT A CATEGORY BELOW SURFACE DEWPOINT OBSERVED DURING
THE AFTERNOON TODAY WITH JUST A FEW DEGREES OF DRY ADVECTION
EXPECTED TONIGHT. THIS ADDS SOME CONFIDENCE TO FOG COVERAGE IN OUR
AREA COMBINED WITH THE WIDESPREAD OBSERVATIONAL EVIDENCE OVER
WISCONSIN/IOWA/ILLINOIS FROM THIS MORNING.
LONG TERM...MONDAY THROUGH SATURDAY
THE ANTICIPATED WAVELENGTH BROADENING OF UPPER LEVEL RIDGE IS
FORECASTED TO ACCELERATE MONDAY WITH A CENTROID OF THE UPPER LEVEL
GEOPOTENTIAL HEIGHT MAX BREAKING OFF OF THE RIDGE PEAK AND ROLLING
EASTWARD INTO MUCH OF EASTERN CANADA. MODELS FORECAST A WEAKNESS
DEVELOPING WITHIN THE RIDGE FOR THE BEGINNING OF THE WEEK
PERIOD....BUT ALL INDICATIONS ARE THE SLIGHTLY COOLER MIDLEVEL
TEMPERATURES WILL REMAIN CONFINED TO THE OHIO RIVER VALLEY. A VERY
WEAK BAROCLINIC ZONE...WITH NO JET SUPPORT ALOFT...WILL MATERIALIZE
TO SOUTH OF THE OHIO/MICHIGAN BORDER. IT IS ALONG THIS FEATURE AND
TO THE SOUTH WHERE A BETTER CHANCE EXISTS FOR A POP-UP SHOWER OR
THUNDERSTORM. FOR SOUTHEASTERN MICHIGAN THE FORECAST WILL REMAIN
DRY. WITH THE RIDGE EXPANDING EAST...THE HEAT AND UNCOMFORTABLE
CONDITIONS WILL GET STARTED WITH TEMPERATURES AND DEWPOINTS
COMBINING TO PUSH HEAT INDICES INTO THE MID TO UPPER 80S FOR MONDAY.
THE WEAK TEMPERATURE DISCONTINUITY OR FRONTAL ZONE IS THEN
FORECASTED TO LIFT SLIGHTLY NORTHWARD TUESDAY. THIS WILL OCCUR HAS
LOOSELY DEFINED AND WEAK SHORTWAVE ENERGY CONSOLIDATES INTO SOME
ORGANIZATION OVER GREATER PORTIONS OF OHIO AND INDIANA. A PLAN
VIEW OF MIDLEVEL OR 700 MB TEMPERATURES SHOWS THIS WITH SOME SUB
7C 700 MB TEMPERATURES LIFTING ACROSS THE STATELINE INTO FAR
SOUTHEASTERN MICHIGAN. IT IS A STEEP LAPSE RATE POCKET FROM
800-700MB THAT MAY THEN ALLOW FOR SOME CONVECTIVE SHOWER/TSTORM
DEVELOPMENT TUESDAY AFTERNOON AS THE BOUNDARY LIFTS NORTHWARD.
WILL REFRAIN FROM ADDING A PRECIPITATION MENTION THIS FORECAST
ISSUANCE AS POTENTIAL STILL APPEARS TO BE LESS THAN 20 PERCENT.
WORKING OFF WARMER MINS...TEMPERATURES ARE EXPECTED TO MODERATE A
FEW MORE DEGREES WITH HIGHS EASILY REACHING THE MIDDLE TO UPPER
80S TUESDAY AFTERNOON. HEAT INDICES ARE FORECASTED TO ECLIPSE THE
90 DEGREE MARK.
EXTENDED...BY THE MIDDLE OF NEXT WEEK...SOUTHEAST MICHIGAN WILL BE
FIRMLY UNDER THE UPPER LEVEL RIDGING AND SOUTHERLY FLOW. THIS WILL
BRING A CONTINUATION OF ABOVE NORMAL TEMPERATURES ALONG WITH DRY
CONDITIONS WHICH WILL PERSIST THROUGH THE REMAINDER OF THE WEEK AND
INTO THE WEEKEND.
MARINE...
VERY QUIET MARINE WEATHER WILL PERSIST ON THE GREAT LAKES THROUGH
MUCH OF THE UPCOMING WEEK. A STRONG RIDGE OF UPPER LEVEL HIGH
PRESSURE WILL MAINTAIN LIGHT FLOW AND A GENERAL SOUTHWEST WIND
DIRECTION.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...DENSE FOG ADVISORY UNTIL 9 AM EDT MONDAY FOR MIZ047>049-053>055-
060>063.
DENSE FOG ADVISORY FROM 3 AM TO 9 AM EDT MONDAY FOR MIZ068>070-075-
076-082-083.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....JVC
UPDATE.......JVC
SHORT TERM...BT
LONG TERM....CB/SS
MARINE.......CB
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1101 PM EDT SUN AUG 30 2015
.UPDATE...
CLEAR SKIES, CALM WINDS, AND DEWPOINTS SOLIDLY IN THE 60S ARE GIVING
WAY TO INCREASINGLY WIDESPREAD DENSE FOG AT 03Z, MAINLY NORTH OF
M59. IN THE IMMEDIATE DETROIT AREA, LINGERING CLOUDS AND SLOW
COOLING FROM WARMER DAYTIME TEMPS ARE DELAYING ONSET. WHEN ALL IS
SAID AND DONE, HOWEVER, EXPECT THAT ALL COUNTIES WILL SEE A
NOTEWORTHY COMPONENT OF DENSE FOG WORTHY OF AN ADVISORY. A DENSE FOG
ADVISORY IS THEREFORE FORTHCOMING FOR THE I-69 COUNTIES NORTH VALID
IMMEDIATELY. SEEING AS THOUGH SITES SUCH AS ADG, DTW, AND ARB HAVE
YET TO DIP BELOW 1SM (6SM IN THE CASE OF DTW) WILL START THE
REMAINDER OF COUNTIES AT 06Z WITH THE UNDERSTANDING THAT THERE MAY
YET BE SOME FURTHER DELAY IN URBAN CORRIDORS.
&&
.AVIATION...ISSUED 635 PM EDT SUN AUG 30 2015
SCATTERED SHOWERS, ISOLATED THUNDERSTORMS, AND WHAT REMAINS OF
DIURNAL CU WILL DIMINISH OVER THE NEXT COUPLE OF HOURS AS THE
BOUNDARY LAYER STABILIZES. DESPITE A HEALTHY COVERAGE OF MOSTLY
TRANSPARENT CIRRUS, RADIATING CONDITIONS SHOULD BE SUFFICIENTLY
FAVORABLE FOR IFR/LIFR TO DEVELOP LATE TONIGHT AS HIGH PRESSURE
SETTLES OVER THE AREA.
//DTW THRESHOLD PROBABILITIES...
* LOW FOR VSBY AOB 1/2 MILE 09-12Z.
&&
.PREV DISCUSSION...ISSUED 353 PM EDT SUN AUG 30 2015
SHORT TERM... AFTERNOON AND TONIGHT
MID AFTERNOON MESOANALYSIS INDICATES LOWEST 100 MB MLCAPE IN THE
1000-1500 J/KG RANGE FROM THE OHIO BORDER TO ABOUT THE I-96/696
CORRIDOR. THE RADAR TREND HAS BEEN RELATIVELY SOFT GIVEN THE
INSTABILITY SUGGESTING EITHER DAYTIME HEATING NEEDS A LITTLE MORE
TIME OR THAT MID LEVEL SUBSIDENCE IS SUFFICIENT TO CAP DEEP
CONVECTION. MOST RECENT RAP MODEL SOUNDINGS SUPPORT THE LATTER WITH
THE DEPICTION OF SURFACE BASED PARCELS JUST BARELY CLEARING THE
DEEPENING 700-500 MB WARM/STABLE LAYER. AT THE SAME TIME...THE
NEWEST MESOSCALE MODELS ALLOWING EXPLICIT CONVECTION PRODUCE
SCATTERED COVERAGE OF SHOWERS WITH AN ISOLATED THUNDERSTORM DURING
PEAK HEATING FROM LATE AFTERNOON THROUGH EARLY EVENING. THE MOST
PRUDENT APPROACH IS TO ALLOW FOR AN ISOLATED THUNDERSTORM
CONSIDERING A WIND HAZARD IS IN PLAY CONDITIONAL ON STORM
DEVELOPMENT. WV SATELLITE IMAGERY CONTINUES TO SUPPORT MODEL
SOUNDINGS THAT SHOW VERY DRY AIR CENTERED AROUND 500 MB. THE DRY AIR
IS SYMPTOMATIC OF THE LARGER SCALE SUBSIDENCE OCCURRING THROUGH THE
MID LEVELS THAT IS INHIBITING CONVECTION IN THE FIRST PLACE...BUT
WHICH ALSO COULD PROVIDE STRONG NEGATIVE BUOYANCY POTENTIAL SHOULD
INSTABILITY BECOME ADEQUATE FOR DEEP CONVECTION.
POINTS NORTH OF THE I-69 CORRIDOR WILL BE DRY BUT CLOUDY DURING THE
LATE AFTERNOON AND EVENING...AND ANY SHOWERS/STORMS THAT ARE ABLE TO
FORM SOUTH OF THAT LINE WILL QUICKLY DISSIPATE WITH THE LOSS OF
SURFACE HEATING BY MID EVENING. THAT WILL LEAVE A CLEARING TREND TO
OCCUR THROUGH THE OVERNIGHT AS SURFACE HIGH PRESSURE BECOMES RE-
ESTABLISHED OVER LOWER MICHIGAN. THE NORTHERN FRINGES OF THE SURFACE
HIGH REMAINS SET TO ESTABLISH AREAS OF FOG IN SE MICHIGAN TOWARD
SUNRISE AS MIN TEMPS SETTLE IN THE LOWER TO MID 60S. PROJECTED MIN
TEMPS ARE ABOUT A CATEGORY BELOW SURFACE DEWPOINT OBSERVED DURING
THE AFTERNOON TODAY WITH JUST A FEW DEGREES OF DRY ADVECTION
EXPECTED TONIGHT. THIS ADDS SOME CONFIDENCE TO FOG COVERAGE IN OUR
AREA COMBINED WITH THE WIDESPREAD OBSERVATIONAL EVIDENCE OVER
WISCONSIN/IOWA/ILLINOIS FROM THIS MORNING.
LONG TERM...MONDAY THROUGH SATURDAY
THE ANTICIPATED WAVELENGTH BROADENING OF UPPER LEVEL RIDGE IS
FORECASTED TO ACCELERATE MONDAY WITH A CENTROID OF THE UPPER LEVEL
GEOPOTENTIAL HEIGHT MAX BREAKING OFF OF THE RIDGE PEAK AND ROLLING
EASTWARD INTO MUCH OF EASTERN CANADA. MODELS FORECAST A WEAKNESS
DEVELOPING WITHIN THE RIDGE FOR THE BEGINNING OF THE WEEK
PERIOD....BUT ALL INDICATIONS ARE THE SLIGHTLY COOLER MIDLEVEL
TEMPERATURES WILL REMAIN CONFINED TO THE OHIO RIVER VALLEY. A VERY
WEAK BAROCLINIC ZONE...WITH NO JET SUPPORT ALOFT...WILL MATERIALIZE
TO SOUTH OF THE OHIO/MICHIGAN BORDER. IT IS ALONG THIS FEATURE AND
TO THE SOUTH WHERE A BETTER CHANCE EXISTS FOR A POP-UP SHOWER OR
THUNDERSTORM. FOR SOUTHEASTERN MICHIGAN THE FORECAST WILL REMAIN
DRY. WITH THE RIDGE EXPANDING EAST...THE HEAT AND UNCOMFORTABLE
CONDITIONS WILL GET STARTED WITH TEMPERATURES AND DEWPOINTS
COMBINING TO PUSH HEAT INDICES INTO THE MID TO UPPER 80S FOR MONDAY.
THE WEAK TEMPERATURE DISCONTINUITY OR FRONTAL ZONE IS THEN
FORECASTED TO LIFT SLIGHTLY NORTHWARD TUESDAY. THIS WILL OCCUR HAS
LOOSELY DEFINED AND WEAK SHORTWAVE ENERGY CONSOLIDATES INTO SOME
ORGANIZATION OVER GREATER PORTIONS OF OHIO AND INDIANA. A PLAN
VIEW OF MIDLEVEL OR 700 MB TEMPERATURES SHOWS THIS WITH SOME SUB
7C 700 MB TEMPERATURES LIFTING ACROSS THE STATELINE INTO FAR
SOUTHEASTERN MICHIGAN. IT IS A STEEP LAPSE RATE POCKET FROM
800-700MB THAT MAY THEN ALLOW FOR SOME CONVECTIVE SHOWER/TSTORM
DEVELOPMENT TUESDAY AFTERNOON AS THE BOUNDARY LIFTS NORTHWARD.
WILL REFRAIN FROM ADDING A PRECIPITATION MENTION THIS FORECAST
ISSUANCE AS POTENTIAL STILL APPEARS TO BE LESS THAN 20 PERCENT.
WORKING OFF WARMER MINS...TEMPERATURES ARE EXPECTED TO MODERATE A
FEW MORE DEGREES WITH HIGHS EASILY REACHING THE MIDDLE TO UPPER
80S TUESDAY AFTERNOON. HEAT INDICES ARE FORECASTED TO ECLIPSE THE
90 DEGREE MARK.
EXTENDED...BY THE MIDDLE OF NEXT WEEK...SOUTHEAST MICHIGAN WILL BE
FIRMLY UNDER THE UPPER LEVEL RIDGING AND SOUTHERLY FLOW. THIS WILL
BRING A CONTINUATION OF ABOVE NORMAL TEMPERATURES ALONG WITH DRY
CONDITIONS WHICH WILL PERSIST THROUGH THE REMAINDER OF THE WEEK AND
INTO THE WEEKEND.
MARINE...
VERY QUIET MARINE WEATHER WILL PERSIST ON THE GREAT LAKES THROUGH
MUCH OF THE UPCOMING WEEK. A STRONG RIDGE OF UPPER LEVEL HIGH
PRESSURE WILL MAINTAIN LIGHT FLOW AND A GENERAL SOUTHWEST WIND
DIRECTION.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
UPDATE.......JVC
AVIATION.....JVC
SHORT TERM...BT
LONG TERM....CB/SS
MARINE.......CB
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
329 AM EDT SAT AUG 29 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 411 PM EDT FRI AUG 28 2015
WV IMAGERY AND RAP ANALYSIS INDICATED MAINLY ZONAL MID/UPPER LEVEL
FLOW ALONG THE US/CANADIAN BORDER. A SHORTWAVE TROUGH FROM NW
ONTARIO INTO NRN MN SUPPORTED SCT SHRA/TSRA OVER THE MN ARROWHEAD
INTO NRN ONTARIO WEST OF THUNDER BAY. TO THE SOUTH...ANOTHER SHRTWV
OVER IA BRINGING SHOWERS FROM NE IA THROUGH SW WI WAS SLOWLY LIFTING
TO THE ENE. THE LEADING EDGE OF THE PCPN TO NEAR AUW.
OTHERWISE...PARTLY TO MOSTLY CLOUDY SKIES PREVAILED ACROSS UPPER MI
WITH TEMPS IN THE MID 70S.
TONIGHT...MOST OF THE CWA WILL REMAIN BETWEEN THE INFLUENCE OF THE
NRN AND SRN STREAM SHORTWAVES. RADAR TRENDS AND SHORT RANGE MODELS
SUGGEST THAT THE RAIN OVER WI TO AFFECT MAINLY THE SRN TIER ALONG
AND SOUTH OF US-2 FROM IMT EASTWARD. SHRA/TSRA WITH THE NRN STREAM
SHRTWV MAY BRUSH MAINLY THE KEWEENAW BY LATE THIS EVENING AND
POSSIBLY INTO THE NRN PORTION OF UPPER MI. FCST MUCAPE VALUES INTO
THE 500-1000 J/KG RANGE OVER THE NORTH COULD ALSO SUPPORT ISOLD
TSRA.
SATURDAY...SOME SHOWERS MAY LINGER OVER THE SE PORTION OF THE CWA
ASSOCIATED WITH REMNANTS OF THE WI SHRTWV OR POSSIBLY AIDED BY A
TRAILING SHRTWV DIVING INTO NRN WI. HOWEVER...EXPECT THE PCPN TO
SLIDE OFF TO THE EAST BY AFTERNOON. WITH SOME CLEARING INTO THE WEST
HALF BY AFTERNOON...TEMPS WILL REBOUND INTO THE MID AND UPPER 70S.
GREATER CLOUD COVER OVER THE EAST AND WITH SRLY FLOW OFF OF LAKE
MI...TEMPS WILL REMAIN IN UPPER 60S AND LOWER 70S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 328 AM EDT SAT AUG 29 2015
MODELS INDICATE RIDGE MOVING IN FROM THE NORTHERN PLAINS WILL
PROVIDE DRY WEATHER FOR THE EARLY PART OF NEXT WEEK....THEN A SERIES
OF WEAKER SHORTWAVES MOVING UP THE BACKSIDE OF RIDGE COULD BRING
SOME ISOLD TO SCT CONVECTION INTO THE UPPER GREAT LAKES BY MIDWEEK.
MODELS THEN SUGGEST MID-UPPER LEVEL RIDGE COULD REESTABLISH ITSELF
IN DEVELOPING BLOCKING PATTERN OVER NORTH AMERICA AND GREATLY
AMPLIFY INTO THE UPPER GREAT LAKES BY THE END OF NEXT WEEK/WEEKEND.
WELL ABOVE NORMAL TEMPS LOOK LIKE A GOOD BET THROUGH MUCH OF THE
WEEK WITH THE POTENTIAL FOR NEAR RECORD WARM TEMPS LATE IN THE WEEK.
SUN AND MON...MODELS SHOW NORTHERN PLAINS RIDGE MOVING INTO THE
UPPER GREAT LAKES IN RESPONSE TO BROAD TROUGH DEVELOPING OVER WRN
CANADA INTO THE PAC NW. WITH 8H TEMPS RISING TO AROUND 20C AND DEW
POINTS IN THE LOWER 60S IN A SW FLOW...EXPECT MUGGY CONDITIONS
WITH HIGH TEMPS BY MONDAY TO REACH INTO THE LOWER TO MID 80S.
TUE INTO THU...MODELS ADVERTISE A SERIES OF SHORTWAVES MOVING UP
BACKSIDE OF MID-UPPER LEVEL RIDGE AS RIDGE AXIS PUSHES EAST OF THE
WESTERN GREAT LAKES. SINCE TIMING OF THESE WEAKER SHORTWAVES IS
POORLY RESOLVED BY MODELS WILL CONTINUE TO INCLUDE ONLY LOW CHC POPS
FOR POSSIBLE CONVECTION FROM THESE FEATURES THROUGH THE PERIOD.
TOWARD END OF NEXT WEEK/WEEKEND...MODELS SUGGEST RIDGE MID-UPPER
LEVEL RIDGE WILL REESTABLISH ITSELF AND GREATLY AMPLIFY INTO THE
CENTRAL CONUS AND GREAT LAKES REGION AS A BLOCKING PATTERN DEVELOPS
WITH A BROAD TROUGH PERSISTING OVER WRN CANADA INTO THE U.S. WEST
COAST AND A CUT-OFF LOW DEVELOPING NEAR THE CANADIAN MARITIMES OVER
THE NORTH ATLANTIC. WITH MANY OF THE MODELS FORECASTING 5H HEIGHTS
OF 590 DM OR GREATER AND 8H TEMPS GREATER THAN 20C...EXPECT HIGH
TEMPS WELL INTO THE 80S AND PERHAPS EVEN APPROACHING 90F OVER
PORTIONS OF THE WEST HALF OF UPPER MI. WOULD NOT BE SURPRISED TO SEE
A FEW RECORD HIGH TEMPS FALL FRI INTO SAT OVER THE WEST HALF OF THE
CWA. MUGGY CONDITIONS WILL CONTINUE WITH DEWPOINTS IN THE LOWER TO
MID 60S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 128 AM EDT SAT AUG 29 2015
VFR CONDITIONS WILL CONTINUE THROUGH THIS FCST PERIOD AT ALL SITES.
POSSIBLE ISOLD TSRA COULD AFFECT KCMX TERMINAL EARLY THIS MORNING AS
CLUSTERS OF TSRA OVER WESTERN LK SUPERIOR SLIDE TOWARD KEWEENAW
PENINSULA WHILE WEAKENING. WILL MONITOR AND UPDATE AS NECESSARY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 411 PM EDT FRI AUG 28 2015
EXPECT A PERIOD OF MODERATE SW WINDS LATE TONIGHT INTO EARLY SATURDAY
GUSTING TO 15-20 KNOTS. OTHERWISE...A GENERALLY WEAK PRES GRADIENT
WILL DOMINATE THE UPPER LAKES INTO EARLY NEXT WEEK. ON MOST
DAYS...WINDS WILL BE UNDER 15KT. LOOKS LIKE THE LIGHTEST WINDS WILL
OCCUR OVER THE WEEKEND WITH HIGH PRES RIDGE MORE FIRMLY IN CONTROL.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...VOSS
AVIATION...JLA
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
130 AM EDT SAT AUG 29 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 411 PM EDT FRI AUG 28 2015
WV IMAGERY AND RAP ANALYSIS INDICATED MAINLY ZONAL MID/UPPER LEVEL
FLOW ALONG THE US/CANADIAN BORDER. A SHORTWAVE TROUGH FROM NW
ONTARIO INTO NRN MN SUPPORTED SCT SHRA/TSRA OVER THE MN ARROWHEAD
INTO NRN ONTARIO WEST OF THUNDER BAY. TO THE SOUTH...ANOTHER SHRTWV
OVER IA BRINGING SHOWERS FROM NE IA THROUGH SW WI WAS SLOWLY LIFTING
TO THE ENE. THE LEADING EDGE OF THE PCPN TO NEAR AUW.
OTHERWISE...PARTLY TO MOSTLY CLOUDY SKIES PREVAILED ACROSS UPPER MI
WITH TEMPS IN THE MID 70S.
TONIGHT...MOST OF THE CWA WILL REMAIN BETWEEN THE INFLUENCE OF THE
NRN AND SRN STREAM SHORTWAVES. RADAR TRENDS AND SHORT RANGE MODELS
SUGGEST THAT THE RAIN OVER WI TO AFFECT MAINLY THE SRN TIER ALONG
AND SOUTH OF US-2 FROM IMT EASTWARD. SHRA/TSRA WITH THE NRN STREAM
SHRTWV MAY BRUSH MAINLY THE KEWEENAW BY LATE THIS EVENING AND
POSSIBLY INTO THE NRN PORTION OF UPPER MI. FCST MUCAPE VALUES INTO
THE 500-1000 J/KG RANGE OVER THE NORTH COULD ALSO SUPPORT ISOLD
TSRA.
SATURDAY...SOME SHOWERS MAY LINGER OVER THE SE PORTION OF THE CWA
ASSOCIATED WITH REMNANTS OF THE WI SHRTWV OR POSSIBLY AIDED BY A
TRAILING SHRTWV DIVING INTO NRN WI. HOWEVER...EXPECT THE PCPN TO
SLIDE OFF TO THE EAST BY AFTERNOON. WITH SOME CLEARING INTO THE WEST
HALF BY AFTERNOON...TEMPS WILL REBOUND INTO THE MID AND UPPER 70S.
GREATER CLOUD COVER OVER THE EAST AND WITH SRLY FLOW OFF OF LAKE
MI...TEMPS WILL REMAIN IN UPPER 60S AND LOWER 70S.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 344 PM EDT FRI AUG 28 2015
COULD SEE A FEW SHOWERS IN THE FIRST 6 HOURS OF THE FORECAST SAT
NIGHT...BUT THINK VAST MAJORITY OF PRECIP ASSOCIATED WITH A
SHORTWAVE WILL BE OUT OF THE AREA. OTHERWISE...PRECIP CHANCES ARE
LOW IN THE LONG TERM AS A MID-UPPER RIDGE MOVES IN AND SITS OVER THE
CENTRAL TO ERN CONUS. COULD SEE SOME PRECIP MID-LATE NEXT WEEK AS
SHORTWAVES TRY TO TOP THE RIDGE...BUT PREDICTABILITY IS TOO LOW TO
JUSTIFY ANYTHING ABOVE SLIGHT CHANCE POPS.
TEMPS WILL BE ON THE INCREASE AND WILL ALREADY BE ABOVE NORMAL SUN.
HIGHS SUN WILL BE IN THE MID 70S TO LOW 80S AS 850MB TEMPS START OUT
IN THE MID TEENS C. 850MB TEMPS THROUGH THE REST OF THE WEEK WILL BE
AROUND 20C...RESULTING IN HIGH TEMPS 10 OR MORE DEGREES ABOVE
NORMAL.
COULD SEE SOME PATCHY FOG AROUND SAT NIGHT INTO EARLY SUN MORNING
AND AGAIN SUN NIGHT INTO MON MORNING AS HIGH PRESSURE/SUBSIDENCE
MOVES IN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 128 AM EDT SAT AUG 29 2015
VFR CONDITIONS WILL CONTINUE THROUGH THIS FCST PERIOD AT ALL SITES.
POSSIBLE ISOLD TSRA COULD AFFECT KCMX TERMINAL EARLY THIS MORNING AS
CLUSTERS OF TSRA OVER WESTERN LK SUPERIOR SLIDE TOWARD KEWEENAW
PENINSULA WHILE WEAKENING. WILL MONITOR AND UPDATE AS NECESSARY. &&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 411 PM EDT FRI AUG 28 2015
EXPECT A PERIOD OF MODERATE SW WINDS LATE TONIGHT INTO EARLY SATURDAY
GUSTING TO 15-20 KNOTS. OTHERWISE...A GENERALLY WEAK PRES GRADIENT
WILL DOMINATE THE UPPER LAKES INTO EARLY NEXT WEEK. ON MOST
DAYS...WINDS WILL BE UNDER 15KT. LOOKS LIKE THE LIGHTEST WINDS WILL
OCCUR OVER THE WEEKEND WITH HIGH PRES RIDGE MORE FIRMLY IN CONTROL.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...JLA
MARINE...JLB
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
647 PM CDT SUN AUG 30 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 400 PM CDT SUN AUG 30 2015
WATER VAPOR IMAGERY ALONG WITH RAP H5 HEIGHT ANALYSIS SHOWS UPPER
RIDGING BUILDING IN THIS AFTERNOON. A TROUGH EJECTING ACROSS THE
NRN ROCKIES HAS ALLOWED A BROAD AREA OF SFC LOW PRESSURE TO FORM
ACROSS ERN MT/NRN NODAK/SRN CANADA. IT IS THIS LOW THAT HAS
RESULTED IN AN INCREASING PRESSURE GRADIENT AND THE STRONGER SOUTH
WINDS WE HAVE SEEN TODAY.
IT IS THESE SOUTH WINDS THAT MAKE THE FORECAST FOR TONIGHT TRICKY.
NAM BUFR SOUNDINGS MONDAY MORNING LOOK LIKE CARBON COPIES OF THE MPX
SOUNDING THIS MORNING...WHICH OF COURSE WAS ASSOCIATED WITH ANOTHER
ROUND OF LOW STRATUS. STRATUS IS STILL HANGING TOUGH IN IOWA AND
WITH THE PATTERN TO OUR SOUTHEAST NOT MUCH DIFFERENT FROM WHAT WE
HAVE SEEN THE PAST COUPLE OF NIGHTS...EXPECT STRATUS TO EXPAND AGAIN
TONIGHT...THE QUESTION IS JUST HOW FAR NW DOES IT COME. ONE BIG
DIFFERENCE BETWEEN TODAY AND THE PAST COUPLE OF DAYS IS WE HAVE
STRONGER WINDS AND BETTER BOUNDARY LAYER MIXING TODAY. THE GRADIENT
AND ASSOCIATED WINDS WILL REMAIN IN PLACE THROUGH THE NIGHT...ADDING
A LAYER OF UNCERTAINTY TO THE SKY FORECAST. FOR NOW...DID A SOFT
PLAY FOR THE STRATUS...WITH 40/50% COVERAGE FROM SOUTH CENTRAL MN
INTO EAST CENTRAL MN AND WRN WI LATE TONIGHT/EARLY MONDAY MORNING
AND WILL LET FUTURE SHIFTS UP SKY COVER IF NEED BE WHEN THERE IS A
BETTER HANDLE ON WHERE IT IS GOING.
FOR MONDAY...THE PREVIOUSLY MENTIONED LOW WELL SEND A FRONT ACROSS
THE DAKOTAS...APPROACHING WEST CENTRAL MN BY THE AFTERNOON.
HOWEVER...WE ARE NOT ANTICIPATING ANY ACTIVITY ALONG THE FRONT THIS
FAR SOUTH...SO WE REMOVED WHAT SMALL POPS WERE MENTION MONDAY
AFTERNOON IN OUR NW. BESIDE NONE OF THE HI-RES...DETERMINISTIC...OR
ENSEMBLE MODELS SHOWING ANY PRECIP IN OUR AREA...FORECAST SOUNDINGS
AT AXN AND SURROUNDING SITES SHOW A STRONG WARM NOSE BETWEEN H8 AND
H7 THAT LOOKS TO KEEP A LID ON DEEP MOIST CONVECTION THIS FAR SOUTH.
IN ADDITION...THE WAVE AND ASSOCIATED HEIGHT FALLS DRIVING THIS
FRONT ARE GOING FROM MT TO HUDSON BAY...STAYING WELL NW OF THE
MPX AREA...SO FEEL CONFIDENT IN THE DRY FORECAST FOR MONDAY.
BESIDE DRY...ALL OF THE MODELS SHOW 925-850 TEMPS IN WRN MN DROPPING
A COUPLE OF DEGS C MONDAY AFTERNOON COMPARED TO WHAT WE ARE SEEING
TODAY...SO EXPECT HIGHS TO BE NO WARMER THAN WHAT WE ARE SEEING
TODAY AND LIKELY A COUPLE OF DEGREES COOLER IN WRN MN.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 400 PM CDT SUN AUG 30 2015
NO BIG CHANGES TO THE LONG TERM FORECAST AS THE PATTERN STILL
FAVORS RIDGING IN THE CENTRAL CONUS AND ABOVE NORMAL TEMPERATURES
LASTING INTO LABOR DAY WEEKEND.
THE LONGWAVE RIDGE AXIS WILL CONTINUE TO SHIFT EAST ON
TUESDAY...BUT THE BIGGEST RESERVOIR OF WARMTH WILL LINGER FROM THE
FOUR CORNERS UP THROUGH THE NORTHERN PLAINS. THE NAEFS
STANDARDIZED 850MB TEMPERATURE ANOMALIES ARE COMMONLY BETWEEN TWO
AND THREE SIGMA OVER THE NEXT WEEK IN THESE AREAS. AS THE 500MB
RIDGE AXIS SLIDES EAST ON TUESDAY THE LONGWAVE PATTERN LOSES SOME
OF ITS AMPLITUDE AND THE 850MB TEMPERATURE ADVECTION DECREASES
BEFORE REACHING THE FORECAST AREA. AS A RESULT...THE FORECAST AREA
WILL MAINTAIN MID 80S FOR HIGHS AS WE HEAD TOWARD MID WEEK...BUT
THE TEMPERATES WILL NOT APPROACH THE MID /AND EVEN UPPER/ 90S
THAT ARE CURRENTLY BEING OBSERVED IN THE DAKOTAS THIS AFTERNOON.
WESTERN MN IS ALREADY SEEING DEWPOINTS IN THE UPPER 60S AND
EASTERN MN AND WESTERN WI WILL SOON FOLLOW...THESE DEWPOINTS WILL
LINGER THROUGH THE WEEK AND THE DEWPOINT WILL MOST LIKELY HIT 70
DEGREES IN MANY LOCATIONS THIS WEEK. IN THE WED-THU TIME
FRAME...MUCH OF THE 12Z GUIDANCE HINTS AT THE CHANCE FOR RAIN WITH
MOISTURE TRANSPORT EMBEDDED IN THE LOW LEVEL SOUTHWEST FLOW. THE
FORCING ISNT EXTREMELY...BUT THERE IS ELEVATED INSTABILITY AND
THE CAP ISNT OVERLY STRONG EITHER WITH THE 12-14C AIR AT 700MB
REMAINING WEST OF THE AREA IN THE DAKOTAS. THEREFORE...WE
MAINTAINED THE SMALL POPS IN THE FORECAST...BUT ADMITTEDLY THERE
IS LOW CONFIDENCE ON TIMING/AMOUNTS AND EVEN IF THERE WILL BE MUCH
CONVECTIVE INITIATION LOCALLY.
THE PERSISTENT TROUGH OVER THE GULF OF ALASKA AND PACIFIC
NORTHWEST FINALLY LOOKS TO MAKE SOME EASTERN PROGRESS AS WE HEAD
TOWARD THE BACK HALF OF LABOR DAY WEEKEND. THE OPERATIONAL
GUIDANCE AND ENSEMBLE OUTPUT HAS SLIGHTLY SLOWED THE ARRIVAL OF
THE COLD FRONT...BUT AT THE VERY LEAST WE CAN SAY NEXT WEEKEND
LOOKS MORE UNSETTLED WITH A PATTERN SHIFT LOCALLY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 647 PM CDT SUN AUG 30 2015
PERSISTENCE PAYS OFF IN THIS STAGNANT PATTERN...EXPECT MORE
IFR STRATUS TO LIFT NORTH FROM IOWA YET AGAIN TONIGHT. IT COULD
ARRIVE SOONER THAN PREVIOUS NIGHTS DUE TO ITS MORE NORTHERLY
POSITION EARLY THIS EVENING AND STRONGER WINDS IN THE CLOUD
BEARING LAYER. DEW POINTS HAVE ALSO BEEN INCREASING THIS AFTERNOON
DUE TO WAA WHICH COULD CONTRIBUTE TO A QUICKER ARRIVAL. CONFIDENCE
IS REASONABLY HIGH THAT THIS WILL IMPACT STC...MSP...RNH...AND
EAU. NOT SURE YET WHETHER IT WILL REACH AS FAR WEST AS RWF AND
AXN. LOOK FOR A SIMILAR TIME FOR BURN OFF MONDAY...BETWEEN
14-16Z.
KMSP...TWO RELIABLE MODELS SHOW IFR CIGS ARRIVING WITHIN AN HOUR
OF 05Z...WITH ANOTHER SHOWING IT AS EARLY AS 01Z. THINK THE LATE
EVENING ARRIVAL IS A MORE LIKELY BET.
/OUTLOOK FOR KMSP/
TUE-THU...VFR WINDS S 5-15 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...CLF
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION
NWS JACKSON MS
915 PM CDT SUN AUG 30 2015
.DISCUSSION...SHOWERS HAVE ENDED ACROSS THE AREA SO WILL UPDATE THE
ZONES TO REMOVE THE RAIN. WINDS WERE UP IN A FEW LOCATIONS SO
TEMPERATURES WERE NOT FALLING AS QUICKLY. TWEAKED THE HOURLY VALUES
TO ACCOUNT FOR THE WARMER TEMPERATURES. THE RUC SUGGEST THE NORTHEAST
WILL BE A LITTLE COOLER...BUT NOT CONFIDENT DRIER AIR WILL MIX DOWN
OVERNIGHT. WILL MAINTAIN CURRENT LOWS...ESPECIALLY WITH A LIGHT
BREEZE. CLOUDS SHOULD THIN...SO EXPECTING ANOTHER PLEASANT NIGHT.
MODELS WERE SUGGESTING THERE MAY BE SOME PATCHY FOG AROUND...WITH
RAIN IN MERIDIAN COULD SEE SOME IN THE MORNING. LOOKING FOR IT TO BE
PATCHY AT BEST...SO WILL LEAVE IT OUT OF THE FORECAST.
&&
.AVIATION...MAINLY VFR CONDITIONS ARE ANTICIPATED THROUGH THE NEXT
24 HOURS ALTHOUGH SOME PATCHES OF MVFR (TO PERHAPS EVEN BRIEFLY IFR)
CONDITIONS ARE POSSIBLE BETWEEN 10 AND 13 UTC MONDAY MORNING AROUND
GWO/GTR/CBM/NMM/MEI/PIB/HBG. WINDS TOMORROW WILL BE LIGHT AND TEND
TOWARD BEING A LITTLE VARIABLE. /BB/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 69 94 71 95 / 14 10 9 10
MERIDIAN 67 92 69 92 / 15 10 9 8
VICKSBURG 68 95 70 95 / 12 10 8 10
HATTIESBURG 70 95 71 94 / 12 10 9 9
NATCHEZ 69 92 71 91 / 10 10 10 13
GREENVILLE 70 94 72 95 / 15 10 8 12
GREENWOOD 69 93 70 93 / 15 10 10 9
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
JAN/JAN/
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1216 AM CDT SAT AUG 29 2015
.SHORT TERM: (THROUGH LATE TONIGHT)
ISSUED AT 315 PM CDT FRI AUG 28 2015
WATER VAPOR IMAGERY SHOWS THAT A SHORTWAVE TROUGH IS MOVING SLOWLY
EAST ACROSS MISSOURI AT THIS HOUR. LATEST RUNS OF THE RAP SUGGEST
THAT IT WILL TAKE ALL EVENING FOR THIS FIRST SHORTWAVE TO REACH
HALFWAY ACROSS THE CWA WHILE A SECOND SHORTWAVE WILL ENTER WESTERN
MISSOURI BEHIND IT LATER TONIGHT. LOW LEVEL MOISTURE CONVERGENCE
WILL INCREASE ACROSS EASTERN MISSOURI BY LATER THIS EVENING AS LOW
LEVEL JET VEERS AND INCREASES IN SPEED SLIGHTLY. THIS SHOULD CAUSE
AN INCREASE IN COVERAGE IN SCATTERED SHOWERS AND THUNDERSTORMS BY
LATE EVENING AND OVERNIGHT OVER THE REGION BECAUSE OF THE FORCING
FROM THE SHORTWAVES AND THE MOISTURE CONVERGENCE. THE 1KM
REFLECTIVITY FROM THE CAMS DEPICTS THIS PRETTY WELL.
MOS LOWS TONIGHT LOOK REASONABLE GIVEN THE INCREASING DEWPOINTS
AHEAD OF THE COLD FRONT CURRENTLY OVER THE CENTRAL PLAINS.
BRITT
.LONG TERM: (SATURDAY THROUGH NEXT FRIDAY)
ISSUED AT 316 PM CDT FRI AUG 28 2015
AT LEAST SCATTERED SHOWERS AND THUNDERSTORMS CAN BE EXPECTED ON
SATURDAY AND SATURDAY EVENING AS AN UPPER LEVEL TROUGH MOVES
SLOWLY SOUTHEASTWARD THROUGH OUR AREA. IT NOW APPEARS THAT THE
COLD FRONT WILL ONLY MAKE IT INTO NORTHEAST MO AND WEST CENTRAL IL
BEFORE GRADUALLY DISSIPATING. ONLY SLIGHT COOLING IS EXPECTED
ACROSS NORTHEAST MO AND WEST CENTRAL IL SATURDAY AND SATURDAY
NIGHT WITH THE REST OF THE AREA SLIGHTLY WARMER AND MORE HUMID
DESPITE THE CLOUD COVER ON SATURDAY WITH MAINLY A WEAK SOUTHERLY
FLOW. ALTHOUGH THE CHANCE OF PRECIPITATION WILL LESSEN BY LATE
SATURDAY NIGHT AND SUNDAY...THERE MAY STILL BE AT LEAST ISOLATED
SHOWERS/STORMS ACROSS MAINLY SOUTHEAST MO AND SOUTHWEST IL AS THE
WEAKENING UPPER LEVEL TROUGH...SHEAR AXIS MOVES ONLY SLOWLY
SOUTHEASTWARD. A WAMER PERIOD OF WEATHER IS FORECAST FOR THE NEXT
WORK WEEK DUE TO PERSISTENT SOUTHERLY SURFACE/LOW LEVEL FLOW WITH
THE SURFACE/850 MB RIDGE EAST/SOUTHEAST OF OUR AREA...AND AT
LEAST UPPER LEVEL RIDGING ACROSS NORTHWEST MO. WILL KEEP THE
REMAINDER OF THE FORECAST DRY FOR NOW...ALTHOUGH COULD NOT RULE
OUT A FEW SHOWERS/STORMS MAINLY DURING THE AFTERNOON AND EARLY
EVENING HOURS AS THE MODELS CONTINUE TO DEPICT SOME WEAK MID-UPPER
LEVEL TROUGHING...SHEAR AXIS ACROSS MAINLY SOUTHEAST MO AND
SOUTHWEST IL.
GKS
&&
.AVIATION: (FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1208 AM CDT SAT AUG 29 2015
SPECIFICS FOR KCOU, KUIN: RAIN SHOWERS WILL CONTINUE TO INCREASE
IN COVERAGE OVERNIGHT AS A COUPLE OF UPPER LEVEL DISTURBANCES
APPROACH THE REGION. THUNDERSTORMS ARE POSSIBLE AT KUIN DURING THE
AFTERNOON, BUT CURRENT MODELS SUGGEST THE PRECIPITATION WOULD BE
EAST OF KCOU BY THEN. WINDS WILL REMAIN SOUTHEASTERLY TO
SOUTHERLY, THEN BECOME LGT/VAR INVOF A WEAK COLD FRONT.
SPECIFICS FOR KSTL, KSUS, KCPS: THE INCOMING SHIFT NOTICED SOME
LIGHT RAIN ON THEIR COMMUTE TO THE OFFICE IN WELDON SPRING, SO IT
LOOKS LIKE AT LEAST SOME OF THOSE WEAKER ECHOES ON RADAR ARE
PRODUCING RAINFALL. ADDED VCSH TO KSUS AND KSTL FOR THE NEXT FEW
HOURS BASED ON THE CURRENT RADAR TRENDS. SHOWERS SHOULD BECOME
MORE WIDESPREAD WITH TIME AS A COUPLE OF UPPER LEVEL DISTURBANCES
MOVE ACROSS THE AREA. THUNDERSTORMS ARE POSSIBLE DURING THE
AFTERNOON. WINDS WILL REMAIN SOUTHEASTERLY TO SOUTHERLY, THEN
BECOME LGT/VAR INVOF A WEAK COLD FRONT.
KANOFSKY
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1149 PM CDT FRI AUG 28 2015
.DISCUSSION...
Issued at 409 PM CDT FRI AUG 28 2015
Tonight...
Positive tilted shortwave trough as noted in satellite imagery from
IA through KS will slide east tonight. Scattered convection will
form along an associated cold front within a moderately
unstable airmass....at least it will be into the early evening
hours.
A narrow band of convection has finally formed over east
central KS where MLCAPES between 1500-2000J/kg are noted. Further
northeast VFR ceilings within the warm sector have pretty much
capped intense convection as radar shows sputtering area of low
topped showers. The east central KS activity may be the only region
which develops deep convection, albeit the non-severe variety. Will
hit PoPs highest over northern and west central counties until a few
hours after sunset. Thereafter expect a fairly quick drop off in
intensity and coverage as instability hits the skids. Believe the
trend of the HRRR and 12z NAM looks reasonable. QPF will also be
muted. Could see isolated showers form after the passage of the
frontal convection and last into the pre-dawn hours.
Saturday - Sunday...
The above shortwave is expected to flounder over the Mid MO Valley
over the weekend. The h7 shortwave trough will be slow to exit the
CWA resulting in a general region of uvv over the eastern 1/2 of the
CWA. Thinking there will be sufficient breaks in the overcast such
that isolated instability showers/storms will be possible Saturday
afternoon over parts of northeast and central MO. Current
temperature forecast may be a bit too optimistic should the
afternoon clouds fail to break up.
Sunday looks dry with a slight warm-up as the mid level trough
washes out.
Monday - Friday...
The operational models transition to a broadening southwesterly flow
pattern after the upper level ridge axis leans over into the Central
Plains. This will allow warmer more seasonal temperatures and
humidity back into the region. While the h7 temperatures don`t get
overly hot and cap off the environment a lack of any discernible
mid/upper level wave or surface boundaries will greatly limit the
rain chances. As such will go with a dry forecast until some feature
of significance is picked up by the models.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday Night)
Issued at 1149 PM CDT FRI AUG 28 2015
Cold front currently moving through the region which will lead to a
gradual wind shift to the northwest late this evening/early Saturday
morning. Satellite imagery this evening showing plenty of low status
across eastern Nebraska and western Iowa...which fcst models show
gradually shifting south across area terminals after 8z or so. As
such...have elected to highlight IFR probabilities at all sites with
the exception of IXD which may be too far south. Look for minor
improvements in the morning with MVFR cigs likely sticking around
through early to mid-afternoon.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
DISCUSSION...MJ
AVIATION...32
AREA FORECAST DISCUSSION
NWS BILLINGS MT
836 PM MDT SUN AUG 30 2015
.UPDATE...
COLD FRONT IS KNOCKING ON OUR DOOR AS OF 8 PM WITH GUSTY NW WINDS
AT WHITE SULPHUR SPRINGS AND BOZEMAN. IMPRESSIVE 1-3 MB/HR
PRESSURE RISES HAVE BEEN OBSERVED POST-FRONTALLY ACROSS CENTRAL MT
THIS EVENING...SO EXPECT A FAIRLY BRIEF PERIOD OF GUSTY NW WINDS
TO SPREAD ACROSS OUR WESTERN AREAS THROUGH THE REMAINDER OF THE
EVENING...REACHING BILLINGS AROUND 11 PM AND SPREADING ACROSS OUR
EAST THROUGH THE REMAINDER OF THE NIGHT. MODELS CONTINUE TO SHOW
850MB FLOW OF 35-45 KTS ACROSS OUR NORTH CENTRAL AND EAST PARTS.
WHILE THIS SHOULD NOT QUITE BE FULLY REALIZED AS THE SFC BEGINS
TO DECOUPLE STILL EXPECT GUSTS OF 30-45 MPH PER THE PRESSURE RISE
PUSH. SOME PRETTY DRY AIR HAS SPREAD ACROSS OUR SW PARTS WHERE DEW
PTS ARE IN THE UPPER 30S TO LOWER 30S...AND THIS IS WHERE RISK OF
TSTMS IS LOWEST. BETTER FORCING WITH PV IN NORTH CENTRAL MT WILL
PUSH ACROSS OUR NORTH AND COULD SEE A FEW TSTMS LINGER INTO THE
OVERNIGHT HOURS ACROSS OUR N-NE. OTHERWISE SCATTERED ACTIVITY IS
EMBEDDED WITHIN HIGHER THETA-E AIR ACROSS OUR EAST THIS EVENING.
NOTHING SEVERE THOUGH.
REGARDING FIRE WX...WILL LET THE CURRENT RED FLAG WARNING IN
EFFECT RIDE THROUGH THE EVENING FRONTAL PASSAGE AND WIND SHIFT
ACROSS OUR WEST.
FOR BILLINGS...POTENTIAL FOR AN ISOLD TSTM IS MINIMAL BUT CANNOT
BE RULED OUT OVER THE NEXT FEW HOURS AS THERE ARE OUTFLOW
BOUNDARIES LINGERING ACROSS THE AREA. WINDS WILL CERTAINLY BECOME
GUSTY BEFORE MIDNIGHT BUT SHOULD BECOME MUCH LIGHTER WELL BEFORE
SUNRISE AS BURST OF WIND SHOULD BE FAIRLY BRIEF. LOW TEMP AT THE
BILLINGS AIRPORT SO FAR TODAY HAS BEEN A BALMY 72 DEGREES...AND IF
IT STANDS UP WOULD NOT ONLY BE A RECORD WARMEST FOR THE DAY BUT
THE WARMEST LOW OF THE ENTIRE SUMMER. HOWEVER...FROPA WILL ARRIVE
A COUPLE HOURS BEFORE MIDNIGHT STANDARD TIME SO FEEL WE WILL SEE
TEMPS INTO THE 60S BEFORE THE DAY IS OVER.
JKL
&&
.SHORT TERM...VALID FOR MON AND TUE...
A SEASONABLY STRONG COLD FRONT WILL CROSS THE REGION TONIGHT AND
LEAD INTO A PERIOD OF QUIET WEATHER MONDAY AND TUESDAY.
TONIGHT...THE 12 UTC MODELS AND MORE CONTEMPORARY HRRR MODEL RUNS
ARE IN GENERAL AGREEMENT IN SHOWING THE COLD FRONT MOVING THROUGH
THE LIVINGSTON AREA BETWEEN 6 PM AND 9 PM MDT...BILLINGS BETWEEN 7
PM AND 11 MDT...SHERIDAN BETWEEN 11 PM AND 3 AM MDT...AND MILES
CITY AND BAKER AFTER MIDNIGHT. WE EXPECT A SHIFT TO WEST-NORTHWEST
WINDS BEHIND THE FRONT WITH GUSTS TO 45 MPH BASED ON THE DEGREE OF
LOW- AND MID-LEVEL COLD AIR ADVECTION AND THERMAL GRADIENT IN THE
FRONTAL ZONE. THAT/S SUPPORTED BY MOS STATISTICAL OUTPUT /THE MAV
AND MET/ AS WELL. FORECAST SOUNDINGS DO SUGGEST THE BOUNDARY LAYER
MAY BE A BIT TOO DECOUPLED FOR FULL MOMENTUM TRANSFER OF THE 40 KT
WINDS THAT ARE SIMULATED WITHIN 3000 FT AGL OF THE GROUND...BUT WE
BELIEVE THE COLD AIR ADVECTION WILL OVERCOME THAT TENDENCY. A RED
FLAG WARNING CONTINUES THROUGH THE EVENING TO CONVEY THE RISK THIS
COLD FRONTAL PASSAGE WILL PRESENT FOLLOWING LATE-AFTERNOON MIX-OUT
OF GUSTY SOUTHWEST WINDS AND DRYING IN SOUTH CENTRAL MT.
WHERE PRECIPITATION IS CONCERNED...ISOLATED SHOWERS AND STORMS ARE
POSSIBLE WITH THE SHORTWAVE TROUGH PASSAGE DRIVING THE COLD FRONT
EASTWARD...MAINLY THIS EVENING. STRONG MID-LEVEL WINDS SUGGEST A
STRONG STORM IS POSSIBLE...BUT WE FEEL THAT RISK WILL GENERALLY BE
MITIGATED BY A LACK OF STRONGER INSTABILITY.
MONDAY...THE POST-FRONTAL AIR MASS WILL BE COOLER...DRIER...AND
STABLE. HIGHS WILL BE NEAR 80 F WITH AFTERNOON HUMIDITIES AROUND
20 PERCENT PER THE 12 UTC MULTI-MODEL CONSENSUS WE USED TO DERIVE
THE OFFICIAL FORECAST...BUT WIND/S WILL NOT BE ANYTHING TO WRITE
HOME ABOUT.
TUESDAY...DEEPER MIXING TO 700 MB OR MORE AND WARMING TEMPERATURES
ALOFT WITH SOUTHWEST FLOW WILL PROMOTE A WARM-UP INTO THE UPPER
80S AND LOWER 90S F. ATMOSPHERIC MOISTURE CONTENT WON/T CHANGE
TOO MUCH AND THE RESULT WILL BE EVEN LOWER HUMIDITIES WELL DOWN
INTO THE TEENS...THOUGH WINDS AREN/T EXPECTED TO BE STRONG ENOUGH
FOR ANY RED-FLAG-TYPE CONDITIONS. SCHULTZ
.LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN...
UPPER TROUGH OVER THE PACIFIC NORTHWEST WILL MOVE INLAND ON
WEDNESDAY AND THIS SETS UP DEEP SOUTHWEST FLOW OVER SOUTHERN
MONTANA AND NORTHERN WYOMING. HIGHS WILL APPROACH 90 DEGREES ON
WEDNESDAY AHEAD OF COLD FRONT. THIS FRONT WILL MOVE THROUGH
WEDNESDAY NIGHT AND BRING COOLER WEATHER FOR THE END OF THE WEEK.
IN FACT...THIS WILL MARK A DRAMATIC PATTERN CHANGE AS THE WESTERN
TROUGH SWINGS OVER THE NORTHERN ROCKIES THIS WEEKEND. THIS WILL
END THE WARM AND DRY REGIME AND PROVIDE COOLER TEMPERATURES AND A
CHANCE OF PRECIPITATION. SOME OF THE MOUNTAIN TOPS COULD EVEN SEE
A LITTLE SNOW SATURDAY AND SUNDAY...ALTHOUGH THE STRONGER FORCING
AND MOST LIKELY PRECIPITATION PLACEMENT...WOULD BE OVER NORTHERN
MONTANA. TWH
&&
.AVIATION...
STRONG SOUTHWEST WINDS WILL CONTINUE AT KLVM THIS AFTERNOON WITH
SOME GUSTS TO 35KTS. WIDELY SCATTERED SHOWERS AND THUNDERSTORMS
WILL DEVELOP THROUGH THIS EVENING AS A COLD FRONT APPROACHES. SOME
OF THE STORMS NORTHWEST OF BILLINGS COULD BE STRONG WITH WIND
GUSTS TO 45KTS. A COLD FRONT WILL MOVE THROUGH CENTRAL LOCATIONS
FROM KBIL TO KLVM FROM 02-04Z...KSHR 03-05Z AND KMLS AND KBHK
05-07Z. NORTHWEST WINDS WILL GUST TO 35KTS BEHIND THE FRONT.
TWH/AAG
&&
.PRELIMINARY POINT TEMP/POPS...
MON TUE WED THU FRI SAT SUN
-----------------------------------------------------------
BIL 054/082 054/089 059/090 055/075 048/069 047/070 045/071
20/U 00/U 01/U 11/B 23/T 33/T 22/T
LVM 045/080 046/086 051/085 048/072 041/067 038/069 039/073
20/K 00/K 01/B 23/T 44/T 44/T 32/T
HDN 054/083 053/092 057/094 056/080 048/075 048/072 046/073
20/U 00/U 11/U 11/B 22/T 22/T 22/T
MLS 057/082 055/092 059/097 059/081 051/077 049/073 047/072
30/U 00/U 00/U 11/B 22/T 22/T 22/T
4BQ 056/080 055/092 059/096 058/082 053/079 051/071 049/070
30/U 00/U 00/U 01/U 12/T 22/T 22/T
BHK 055/079 054/091 057/095 058/081 051/080 049/073 046/070
30/N 00/U 10/U 11/U 12/T 22/T 22/T
SHR 051/083 049/091 054/092 053/082 046/076 044/070 042/071
30/U 00/U 10/U 01/B 12/T 22/T 22/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...RED FLAG WARNING IN EFFECT UNTIL MIDNIGHT MDT TONIGHT FOR
ZONES 28-29-34-35-39>42-56-63>68.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
820 AM MDT SAT AUG 29 2015
.UPDATE...
WE HAVE ADDED ISOLATED SHOWERS TO THE GARDINER...LIVINGSTON...AND
HARLOWTON AREAS THIS MORNING...AND ISOLATED SHOWERS AND STORMS TO
THOSE SAME AREAS THIS AFTERNOON. THAT MOVE IS BASED ON THE RECENT
TRENDS IN UPSTREAM RADAR IMAGERY AND RECENT HRRR SIMULATIONS. THE
REST OF THE FORECAST LOOKS LARGELY ON TRACK IN ADVERTISING A HOT
DAY EVERYWHERE WITH CRITICAL FIRE WEATHER CONDITIONS ACROSS SOUTH
CENTRAL MT AS SOUTHWEST WINDS INCREASE BY AFTERNOON. SCHULTZ
&&
.SHORT TERM...VALID FOR TDY AND SUN...
HOT AND DRY CONDITIONS WILL PREVAIL TODAY BEFORE SLIGHTLY COOLER
AIR ARRIVES FOR THE DAY SUNDAY. AN UPPER LOW AND TROUGH WILL MOVE
ONTO THE PACIFIC NORTHWEST COAST THIS AFTERNOON RESULTING IN A
SOUTHWEST FLOW ALOFT ACROSS OUR FORECAST AREA. THE BULK OF THE
ENERGY WITH THE SYSTEM WILL REMAIN ACROSS THE PACIFIC NORTHWEST
INTO SOUTHWEST CANADA. A WEAK COLD FRONT WILL MOVE ACROSS OUR FAR
WESTERN ZONES BY EARLY EVENING AND ACROSS THE REMAINING PORTIONS
OF OUR FORECAST AREA OVERNIGHT. THERE WILL BE A SLIGHT CHANCE FOR
A SHOWER OR THUNDERSTORM ALONG THE FRONT THIS EVENING FROM ABOUT
BILLINGS WESTWARD WITH ISOLATED CHANCES SPREADING EAST AFTER
MIDNIGHT.
GUSTY SOUTHWEST WINDS AND HOT TEMPERATURES AHEAD OF THE FRONT
WILL MAKE FOR DANGEROUS FIRE CONDITIONS FROM ABOUT YELLOWSTONE
COUNTY WESTWARD WHERE A RED FLAG WARNING IS IN PLACE THIS
AFTERNOON AND EVENING. FURTHER EAST WINDS ARE NOT EXPECTED TO BE
AS GUSTY BUT WE WILL STILL NEED TO WATCH OUR EAST AS IT WILL BE
MARGINAL. TEMPERATURES WILL BE HOT TODAY WITH NEAR RECORD HIGHS
FOR BILLINGS AND MILES CITY. THE RECORD FOR MILES CITY TODAY IS
101 WITH THE BILLINGS RECORD AT 97 DEGREES.
THE PACIFIC NORTHWEST SYSTEM WILL SHIFT EAST SUNDAY BRINGING AN
AREA OF VORTICITY ACROSS THE STATE. THIS WILL RESULT IN THE
POSSIBILITY OF AN ISOLATED SHOWER OR THUNDERSTORM ACROSS THE
ENTIRE FORECAST AREA. THE SYSTEM WILL SWEEP A STRONGER COLD FRONT
ACROSS THE AREA SUNDAY NIGHT USHERING IN MUCH COOLER TEMPERATURES
FOR MONDAY AS READINGS WILL BE BACK DOWN TO AROUND NORMAL FOR THIS
TIME OF YEAR. HOOLEY
.LONG TERM...VALID FOR MON...TUE...WED...THU...FRI...
POST FRONTAL ZONAL FLOW ON MONDAY WITH COOLER TEMPERATURES BEFORE
BACKING FLOW ON TUESDAY BRINGS A WEAK DOWNSLOPE PATTERN WITH
WARMER TEMPERATURES. THE UPSTREAM TROUGH DRIVING THE BACKING IN
THE FLOW ALOFT STAYS OVER THE PACIFIC NORTHWEST FOR THE REST OF
THE WEEK BUT UNDERGOES FLUCTUATIONS IN ITS DEPTH AND LOCATION AS
ENERGY FLOWS THROUGH THE TROUGH. ONE OF THESE FLUCTUATIONS ON
WEDNESDAY PUSHES THE LEESIDE TROUGH FURTHER EAST AND A WEAK
SURFACE LOW FORMS OVER WESTERN SOUTH DAKOTA. MODELS DIFFER WHETHER
THIS INDUCES A LIGHTER SOUTHWEST SURFACE FLOW OR A WEAK EASTERLY
FLOW SO WILL HAVE TO WATCH FOR HOW CAPPED TEMPERATURES MAY BE ON
WEDNESDAY. SMOKE WILL CONTINUE TO FILTER SUNLIGHT AS THE FLOW
PATTERN SHOULD ADVECT SMOKE FROM CENTRAL IDAHO AND NORTHERN
CALIFORNIA OVER THE AREA BUT MAY NOT BE QUITE AS DENSE AS THIS
PAST WEEK.
AS THE TROUGH DEEPENS OVER THE PACIFIC NORTHWEST ON THURSDAY THE
EJECTING ENERGY TRAVELS A BIT FURTHER SOUTH WHICH MIGRATES THE
SURFACE LOW INTO SOUTHEAST MONTANA. THIS DEEPER EASTERLY FLOW
DEVELOPS A STRONG CAP WHICH DOES PUT A LID ON TEMPERATURES SO
EXPECTING HIGHS TO BE BELOW 80 TOWARDS THE END OF THE WEEK. BORSUM
&&
.AVIATION...
THICK SMOKE WILL CONTINUE TO IMPACT THE AREA TODAY...WITH THE
BIGGEST IMPACTS OVER SOUTHEAST MONTANA. OCCASIONAL MVFR CONDITIONS
CAN BE EXPECTED FROM MILES CITY TO BAKER. AS THE WINDS ALOFT TURN
MORE SOUTHWEST THROUGH THE DAY...CONDITIONS SHOULD IMPROVE THIS
AFTERNOON AND EVENING. A FEW SHOWERS HAVE BEEN ADDED FROM
HARLOWTON TO BIG TIMBER TO LIVINGSTON THIS MORNING. CONTINUED THE
SLIGHT CHANCE OF SHOWERS AND ADDED A SLIGHT CHANCE OF
THUNDERSTORMS IN THESE SAME LOCATIONS THIS AFTERNOON AND EVENING.
THIS ACTIVITY COULD GENERATE STRONG WIND GUSTS. SOUTHWEST WINDS
WILL INCREASE THIS AFTERNOON AROUND LIVINGSTON WITH SOME GUSTS TO
30KTS. MOUNTAINS WILL BE MOSTLY OBSCURED THROUGH THE DAY. TWH
&&
.PRELIMINARY POINT TEMP/POPS...
TDY SUN MON TUE WED THU FRI
-------------------------------------------------------
BIL 096 067/087 052/081 054/087 057/083 053/077 049/075
0/K 22/T 20/U 01/U 11/B 11/B 11/B
LVM 092 060/085 045/079 047/084 049/080 045/074 041/074
2/T 22/T 20/N 00/U 11/B 22/T 22/T
HDN 099 064/089 053/083 053/091 056/087 052/081 049/079
0/K 22/T 20/U 01/U 11/B 11/B 11/B
MLS 101 066/093 059/082 057/091 059/088 055/083 051/080
0/G 02/T 20/U 00/U 11/U 11/B 11/B
4BQ 099 062/093 057/081 056/091 059/089 056/085 053/079
0/K 02/T 20/U 00/U 11/U 11/U 11/B
BHK 098 062/095 055/081 056/091 057/089 054/085 052/079
0/K 02/T 30/N 00/U 11/U 11/U 11/B
SHR 097 058/092 050/082 049/090 053/087 049/082 047/078
0/K 12/T 20/U 01/U 11/B 11/U 11/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 9 PM MDT THIS
EVENING FOR ZONES 28-29-34-35-39>42-56-63>68.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
1037 AM PDT SAT AUG 29 2015
.SYNOPSIS...MOSTLY DRY AND BREEZY CONDITIONS ARE EXPECTED INTO EARLY
NEXT WEEK WITH ANY THUNDERSTORM ACTIVITY CONFINED TO EASTERN MOHAVE
COUNTY SATURDAY AND SUNDAY AFTERNOON. TEMPERATURES WILL REMAIN
SEVERAL DEGREES ABOVE NORMAL SATURDAY THEN BECOME MORE SEASONAL
SUNDAY AND MONDAY. DRY CONDITIONS ALONG WITH BREEZY AND COOLER
CONDITIONS ARE EXPECTED THROUGH THE UPCOMING LABOR DAY WEEKEND.
&&
.UPDATE...THE 12Z LAS VEGAS SOUNDING REVEALED LIMITED MOISTURE STILL
LINGERING OVER SOUTHERN NEVADA WITH ABOUT 1 INCH OF PWAT. A FAIRLY
STRONG INVERSION IN THE 600-550 LAYER SHOULD PROVIDE A GOOD CAP FOR
CONVECTION. ALSO...SLIGHTLY DRIER AIR WILL WORK WITH THE INCREASING
SOUTHWEST FLOW ALOFT. THE LATEST HRRR MODEL INDICATES CONVECTION
DEVELOPING SOUTH OF LAS VEGAS OVER THE MCCULLOUGH RANGE BY EARLY
AFTERNOON. THE AFOREMENTIONED FACTORS SHOULD WORK AGAINST THAT...BUT
IT IS STILL POSSIBLE THAT THE CAP MAY NOT HOLD OVER THE MOUNTAINS
SOUTH OF LAS VEGAS. THE GRIDS WERE UPDATED TO ADD ISOLATED
THUNDERSTORMS OVER SOUTHERN CLARK COUNTY AND ALSO FOR EASTERN
LINCOLN COUNTY.
&&
.AVIATION...FOR MCCARRAN...SOUTHEASTERLY WINDS ARE EXPECTED TO
TRANSITION TO GUSTY SOUTHWEST WINDS BETWEEN 19-20Z. TEMPERATURES
WILL CLIMB TO NEAR 107 DEGREES. THERE IS A SMALL CHANCE OF TS OVER
THE MOUNTAINS TO THE SOUTHEAST OF LAS VEGAS WHICH COULD PRODUCE
GUSTY/ERRATIC OUTFLOW WINDS AT THE TERMINAL. HAVE ADDED A TEMPO
GROUP WITH GUSTY SOUTHEAST WINDS TO ACCOUNT FOR THIS POSSIBILITY.
CHANCES FOR TS WILL DIMINISH AFTER 00Z. SOUTHWEST WINDS WILL
CONTINUE OVERNIGHT...SLIGHTLY STRONGER THAN NORMAL. GUSTY SOUTHWEST
WINDS ARE EXPECTED AGAIN SUNDAY WITH TEMPERATURES DOWN 3-5 DEGREES.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...GUSTY SOUTH TO SOUTHWEST WINDS ARE EXPECTED ACROSS THE
REGION TODAY WITH SPEEDS GENERALLY 10-15KTS WITH GUSTS 20-25 KTS
EAST OF A LINE FROM KELY TO KNXP AND 5-10KTS STRONGER TO THE WEST OF
THIS LINE. STRONG WINDS ACROSS THE SIERRA COULD CREATE AREAS IF
MECHANICAL TURBULENCE TO THE EAST OF THE CREST. THUNDERSTORMS WILL
BE POSSIBLE ACROSS THE HIGHER TERRAIN OF MOHAVE COUNTY...WITH LESSER
CHANCES OVER THE HIGH TERRAIN OF EASTERN LINCOLN...CLARK AND SAN
BERNARDINO COUNTIES. TS TODAY HAVE THE POTENTIAL TO PRODUCE VERY
STRONG/ERRATIC WINDS. CHANCES FOR TS WILL DIMINISH RAPIDLY THIS
EVENING. GUSTY SOUTH TO SOUTHWEST WINDS ARE EXPECTED AGAIN SUNDAY. &&
.PREV DISCUSSION...
140 AM PDT SAT AUG 29 2015
.SHORT TERM...THROUGH MONDAY NIGHT...
TROUGH PUSHING INTO THE WEST COAST WILL BRING DRIER AND MORE STABLE
CONDITIONS TO MUCH OF THE FORECAST AREA TODAY. FORECASTED SOUNDINGS
STILL SHOWING SOME MOISTURE REMAINING IN THE MID LEVELS SO WE SHOULD
STILL SEE A FEW CUMULUS CLOUDS THIS AFTERNOON...BUT THE SOUNDINGS
ARE ALSO SHOWING A WARMING LAYER JUST ABOVE THIS MOISTURE SO
ANYTHING THAT DOES DEVELOP SHOULD REMAIN CAPPED AND THUNDERSTORMS
ARE NOT EXPECTED OUTSIDE OF EASTERN MOHAVE COUNTY WHERE SOME SLIGHT
INSTABILITY REMAINS. WITH THE APPROACH OF THE TROUGH THE SOUTHWEST
FLOW WILL INCREASE THIS AFTERNOON BRINGING BREEZY CONDITIONS TO MUCH
OF THE AREA WITH WINDY CONDITIONS OVER PORTIONS OF ESMERALDA AND
CENTRAL NYE COUNTIES. WINDS ARE EXPECTED TO REMAIN BELOW ANY
ADVISORY LEVELS. TEMPERATURES TODAY ARE EXPECTED TO TOP OUT AS THE
WARMEST OF THE WEEK WITH READINGS GENERALLY ABOUT 6-8 DEGREES ABOVE
NORMAL. EXCESSIVE HEAT CRITERIA IS CURRENTLY AT 108 DEGREES AND FEEL
THAT LAS VEGAS WILL FLIRT WITH THAT NUMBER...ESPECIALLY WITH THE
GOOD MIXING EXPECTED. HOWEVER...SINCE ITS BORDERLINE ELECTED NOT TO
ISSUE ANY EXCESSIVE HEAT PRODUCTS.
SLIGHT COOLING WILL TAKE PLACE SUNDAY AS THE TROUGH MOVES CLOSER TO
THE REGION AND HEIGHTS LOWER. WINDS WILL STILL REMAIN GUSTY OVER THE
EASTERN HALF OF THE AREA WITH BREEZY CONDITIONS EXPECTED. WINDS WILL
BE A BIT LIGHTER ACROSS THE WESTERN HALF OF THE AREA. WE WILL
PROBABLY SEE A FEW CLOUDS OVER EASTERN MOHAVE COUNTY...BUT
THUNDERSTORMS SHOULD REMAIN EAST OF THE AREA. BY MONDAY THERE SHOULD
BE ENOUGH DRY AIR WITH THE SOUTHWEST FLOW THAT ANY LOW LEVEL
MOISTURE WILL BE PUSHED EAST OF THE AREA. TEMPERATURES WILL ALSO
COOL A FEW MORE DEGREES MONDAY AND TOP OUT VERY CLOSE TO NORMAL FOR
THIS TIME OF YEAR.
.LONG TERM...TUESDAY THROUGH SATURDAY.
HAS THE 2015 MONSOON SEASON COME TO AN END? AT LEAST THROUGH THE
UPCOMING LABOR DAY HOLIDAY WEEKEND IT LOOKS SO. MONSOON MOISTURE
WILL BE SUPPRESSED WELL TO OUR SOUTHEAST THANKS TO A BROAD TROUGH
ENCOMPASSING THE GULF OF ALASKA, PAC NW AND WRN CANADA TUESDAY. THE
TROUGH IS FORECAST TO AMPLIFY OVER THE WESTERN STATES BY WEEKS END
AS ENERGY DIGS THROUGH THE NORTHERN GREAT BASIN. REGION WILL REMAIN
DRY THROUGH THE PERIOD WITH BREEZY TO LOCALLY WINDY
AFTERNOON/EVENING HOURS. THE ENTIRE PERIOD LOOKS TO HAVE HIGH
TEMPERATURES BETWEEN 3 TO 5 DEGREES BELOW NORMAL. THE DRIER AIR WILL
ALSO ALLOW FOR MORE COMFORTABLE OVERNIGHT LOWS AS WELL.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION WILL NOT BE
NECESSARY. HOWEVER...SPOTTERS ARE ENCOURAGED TO REPORT ANY
SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING
PROCEDURES. &&
$$
UPDATE.....ADAIR
AVIATION...WOLCOTT
PREV DISCUSSION...GORELOW/PIERCE
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
!--NOT SENT--!
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1157 AM MDT SAT AUG 29 2015
.AVIATION...
18Z TAF CYCLE
WDLY SCT-SCT THUNDERSTORM ACTIVITY IS EXPECTED OVER AND NEAR MOST
MOUNTAIN RANGES AND OVER THE SE PLAINS WITH ISOLD ACTIVITY
ELSEWHERE. SHOWERS AND THUNDERSTORMS WILL GRADUALLY DIMINISH/DISSIPATE
AFTER SUNSET WITH THE EXCEPTION OF FAR WEST-CENTRAL NM WHERE ISOLD
ACTIVITY IS POSSIBLE UNTIL APPROX 07Z. EXPECT BRIEF MVFR CIGS WITH
STRONGER STORMS. AREAS OF DENSE FOG IS LIKELY ONCE AGAIN IN THE
MORENO VALLEY AND KAXX SUNDAY MORNING.
33
&&
.PREV DISCUSSION...341 AM MDT SAT AUG 29 2015...
.SYNOPSIS...
STORM COVERAGE WILL LOWER SLIGHTLY TODAY ALTHOUGH LOCALLY HEAVY
RAIN WILL REMAIN POSSIBLE OVER THE MOUNTAINS...ESPECIALLY
SOUTHWEST AND NORTHERN SACRAMENTOS. THE FAVORED STORM COVERAGE
AREAS WILL SHIFT WESTWARD AND FAVOR THE CONTINENTAL DIVIDE TO THE
ARIZONA BORDER ON SUNDAY. A PACIFIC TROUGH WILL NUDGE CLOSER TO
THE STATE ON MONDAY AND SHIFT THE MAIN STORM COVERAGE FURTHER
EAST. LOCALLY HEAVY RAIN WILL REMAIN POSSIBLE SUNDAY/MONDAY. THE
MONSOON MOISTURE PLUME...ALBEIT DISJOINTED AT TIMES... WILL REMAIN
OVER PORTIONS OF THE STATE THROUGH THE REST OF THE WEEK. A MORE
CONCENTRATED MOISTURE PLUME WILL BE POSSIBLE NEXT WEEKEND AS A
PACIFIC TROUGH STRENGTHENS AND DEEPENS TO THE WEST OF THE STATE.
&&
.DISCUSSION...
MASSAGED POPS/SKY COVER AND WEATHER HERE AND THERE BUT NO MAJOR
CHANGES. THE OVERALL WEATHER THEME APPEARS TO BE SIMILAR. A LITTLE
LESS STORM COVERAGE WITH THE FOCUS GRADUALLY SHIFTING WESTWARD
TODAY. THE MAIN FOCUS ON SUNDAY STILL APPEARS TO BE ACROSS THE
WESTERN THIRD AND CURRENT POPS REFLECT THAT. THE PACIFIC TROUGH
WILL NUDGE CLOSER TO THE STATE ON MONDAY THUS SHIFTING THE MAIN
MOISTURE PLUME A LITTLE FURTHER EAST. IT APPEARS THAT THE PAC
TROUGH WOULD REFORM OR DEEPEN TO THE WEST TUESDAY AND CONTINUE
INTO NEXT WEEKEND. THIS WOULD PLACE THE MAIN MONSOONAL MOISTURE
PLUME OVER SOME PORTION OF THE STATE DURING THIS PERIOD. THUS AN
ACTIVE PERIOD BUT NOTHING OUT OF THE ORDINARY AT THIS TIME. WILL
BE FOLLOWING THE UPPER HIGH PROGRESSION BECAUSE ONCE IT
CONSOLIDATES/LESS HIGH CENTERS/ AND MOVES EAST OF THE STATE THEN A
JUICIER MOISTURE FLOW SHOULD ENSUE. THAT APPEARS POSSIBLE LATE
WEEKEND OR DURING NEXT WEEKEND.
SOME MODEL DISPCREPANCIES FOR TODAYS POP FORECAST. HRRR IS MUCH
MORE BULLISH ACROSS THE EASTERN PLAINS COMPARED TO THE NAM/GFS.
LATEST WATER VAPOR IMAGERY SHOWS A DRIER AND MORE STABLE AIRMASS
POISED TO THE NORTH OF THE STATE SO WOULD EXPECT SOME OF THIS AIR
TO MAKE IT INTO EASTERN NM AS THE DAY PROGRESSES. DESPITE THIS
IMPACT...DECIDED TO BEEF UP POPS A BIT MORE ACROSS THE EC/SE
PLAINS THANKS TO THE LATEST HRRR FORECAST. EITHER WAY...MAIN FOCUS
WILL BE SHIFTING SLIGHTLY MORE TO THE WEST. STEERING FLOW FOR THE
STORMS APPEARS TO BE PRETTY LIGHT DUE TO THE CLOSE PROXIMITY TO
THE HIGH CENTER. ONE NOTABLE STEERING FLOW DIRECTION WOULD BE THE
NE FLOW ORIGINATING FROM THE SANDIA MTNS. THIS FLOW USUALLY BODES
WELL FOR PORTIONS OF THE ABQ NE HEIGHTS SO FOOTHILL RECREATIONALISTS
SHOULD BE COGNIZANT OF THAT POTENTIAL IMPACT. ALSO BEEFED UP QPF
AND POPS ACROSS THE GILA REGION AND NORTHERN SACRAMENTO MTNS.
SINCE THE CELLS SHOULD TRAVEL SOUTHWARD OVER THE SACS...RESIDENCE
TIME MAY NOT BE ALL THAT MUCH...BUT SOMETHING TO WATCH IN TERMS
OF LOCALIZED FLOODING. LOCALIZED FLOODING ALSO POSSIBLE ACROSS
THE GILA REGION. BASED ON THE LATEST NASASPORT SOIL MOISTURE
IMAGERY...CATRON COUNTY APPEARS TO BE RATHER MOIST AS WELL AS
PORTIONS OF THE CENTRAL MTNS/EAST SLOPES.
NOT A LOT OF SIGNIFICANT CHANGES IN THE LATEST MODELING. THE
INITIAL PAC TROUGH IS EXPECTED TO SHEAR OUT ACROSS THE
NORTHERN/CENTRAL ROCKIES/NORTHERN PLAINS SUNDAY/MONDAY. LOCALLY
HEAVY RAIN AND A DIFFUSE MONSOONAL MOISTURE PLUME WILL FAVOR THE
CONTINENTAL DIVIDE WESTWARD SUNDAY. THEN SHIFT A BIT MORE TO THE
EAST ON MONDAY BASED ON THE INITIAL PAC TROUGH EJECTION.
THE PAC TROUGH WILL DEEPEN TO THE WEST OF THE STATE TUESDAY
THROUGH THE END OF THE WEEK. PRETTY TYPICAL PATTERN FOR
SEPTEMBER...AT LEAST BASED ON THE PAST FEW YEARS. MONSOONAL
MOISTURE WILL TRY TO MOVE NORTHWARD AHEAD OF THE TROUGH AND
CONTINUE SH/TS OVER THE FORECAST AREA. SUBTLE DAY TO DAY CHANGES
WILL DEPEND ON WEAK VORTICE WAVES ORIGINATING FROM MEXICO AS WELL
AS A DRIER AND MORE STABLE AIRMASS ROTATING AROUND THE HIGH
CENTER. IT APPEARS THAT BASED ON THE PAC TROUGH PROGRESSION...THE
UPPER HIGH WOULD EVENTUALLY SHIFT EAST OF THE STATE ALTHOUGH THIS
PROGRESSION WILL MOST LIKELY JUMP AROUND A BIT BECAUSE THE MODELS
HAVE BEEN HAVING A HARDER TIME WITH THE PROGRESSION OF THE PAC
TROUGH ALONG THE WEST COAST. EITHER WAY...WOULD EXPECT THE
MONSOONAL MOISTURE PLUME...ORIGINATING FROM MEXICO...TO BECOME
MORE CONSOLIDATED AROUND THE UPPER HIGH OR BECOMING LESS DIFFUSE.
WILL JUST HAVE TO WAIT ON SEE ON THAT ONE. DECIDED TO INCREASE
TEMPS SLIGHTLY ABOVE MODEL GUIDANCE OR SUPER BLEND LEVELS DURING
THE EXTENDED PERIOD. ALSO LOWERED MIN TEMPS IN THE HIGHER MTN
BASINS SUCH AS THE MORENO VALLEY DUE TO LOWERING DEWPOINTS.
50
&&
.FIRE WEATHER...
BACK DOOR FRONT HAS PUSHED WESTWARD TO THE CONTDVD EARLY THIS
MORNING. THIS WILL SET THE STAGE FOR MORE ACTIVITY ACROSS WESTERN NM
TODAY AS COMPARED TO YESTERDAY...THOUGH WETTING RAINS WILL STILL BE
SPOTTY...WITH THE WEST CENTRAL HIGHLANDS BEING THE EXCEPTION. HI-RES
MODELS STILL SHOWING A FAIR AMOUNT OF ACTIVITY ACROSS THE EASTERN
PLAINS AS WELL...BUT WITH DRIER AIR MOVING IN...IT SHOULD NOT BE AS
WIDESPREAD OR AS ORGANIZED AS YESTERDAY. STORM MOTION LOOKS TO SHIFT
A BIT TODAY...PERHAPS MORE TOWARD THE SOUTHWEST OR WEST ACROSS THE
EAST AND MORE TOWARD THE NORTH ACROSS THE WEST.
THE UPPER HIGH IS STILL ON TRACK TO ELONGATE FROM SW TO NE FROM SE
AZ TO NE NM ON SUNDAY. MEANWHILE...THE CENTROID OF THE MID LEVEL
HIGH WILL SHIFT OVER EASTERN NM OR WEST TEXAS. THIS WILL ALLOW MID
LEVEL MOISTURE TO STREAM NORTHWARD ACROSS FAR WESTERN NM AND EASTERN
AZ. APPEARS THAT THE BEST PRECIP CHANCES WILL BE ACROSS THE WESTERN
THIRD OF THE STATE AND SOME SPOTTY HEAVY RAINFALL WILL BE POSSIBLE.
STORM MOTION WILL GENERALLY BE TOWARD THE NORTHEAST AROUND 5-10 MPH.
THE MOISTURE PLUME STILL LOOKS TO SHIFT EASTWARD ON MONDAY...
FOCUSING THE BEST CHANCE FOR TSTMS FROM THE WEST CENTRAL HIGHLANDS
NEWD TO THE NE PLAINS. STORM MOTION WILL LIKELY BE A BIT MORE
ERRATIC...BUT GENERALLY FROM WEST TO EAST OR SW TO NE.
APPEARS THAT THE MOISTURE PLUME WILL STILL BE HOVERING OVER NM ON
TUESDAY...THOUGH NOT AS ROBUST AS SUNDAY OR MONDAY. WILL STILL LOOK
FOR STORMS...MAINLY OVER THE HIGH TERRAIN.
ECMWF AND CANADIAN MODELS CONTINUE TO SHOW THE UPPER HIGH CENTERED
FARTHER SOUTH WEDNESDAY...ALLOWING FOR DRIER WESTERLY FLOW ACROSS
NORTHERN NM. THE GFS HANGS ONTO A DISORGANIZED PLUME ON WEDNESDAY
WITH THE HIGH OVER WEST TEXAS...THOUGH BY THURSDAY...THE HIGH
WEAKENS ALLOWING THAT DRIER AIR INTO NORTHERN NM. WITH MODEL
INCONSISTENCIES OF LATE...HARD TO HAVE A DEFINITE ANSWER...BUT IT
DOES LOOK LIKE MODELS ARE TRENDING TOWARD A DRIER LATTER HALF OF
NEXT WEEK.
VERY LITTLE TEMPERATURE CHANGES OVER THE NEXT SEVERAL DAYS... WITH
HIGHS GENERALLY AT OR ABOVE NORMAL. HUMIDITIES WILL LOWER WED/THURS
MAINLY ACROSS NORTHERN NM IF THE AFOREMENTIONED PATTERN COMES TO
FRUITION. WEAK TRANSPORT WINDS WILL CONTINUE TO RESULT IN POOR TO
FAIR VENT RATES ACROSS NORTH CENTRAL NM TODAY...BUT SHOULD GENERALLY
IMPROVE INTO THE GOOD TO EXCELLENT RANGE NEXT WEEK. ONE EXCEPTION
MAY BE ACROSS THE SANGRE DE CRISTO MOUNTAINS ON MONDAY.
34
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
11
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
532 AM MDT SAT AUG 29 2015
.AVIATION...
12Z TAF CYCLE
LIFR VSBYS IN FG WILL CONTINUE ACROSS THE MORENO VALLEY IN THE
VICINITY OF KAXX THRU APPROX 14Z. LATER TODAY...HI-RES MODELS
SHOWING THAT A SHRA OR TSRA WILL BE POSSIBLE JUST ABOUT
ANYWHERE...THOUGH FAVORED AREAS WILL BE ACROSS THE HIGH TERRAIN.
STORM MOTION WILL VARY...BUT WILL REMAIN LIGHT. BRIEF MVFR CIGS
ARE POSSIBLE IN HEAVY RAIN...ESPECIALLY ACROSS THE SOUTHWEST
MOUNTAINS. CONVECTION SHOULD GENERALLY DIMINISH BY 06Z.
34
&&
.PREV DISCUSSION...341 AM MDT SAT AUG 29 2015...
.SYNOPSIS...
STORM COVERAGE WILL LOWER SLIGHTLY TODAY ALTHOUGH LOCALLY HEAVY
RAIN WILL REMAIN POSSIBLE OVER THE MOUNTAINS...ESPECIALLY
SOUTHWEST AND NORTHERN SACRAMENTOS. THE FAVORED STORM COVERAGE
AREAS WILL SHIFT WESTWARD AND FAVOR THE CONTINENTAL DIVIDE TO THE
ARIZONA BORDER ON SUNDAY. A PACIFIC TROUGH WILL NUDGE CLOSER TO
THE STATE ON MONDAY AND SHIFT THE MAIN STORM COVERAGE FURTHER
EAST. LOCALLY HEAVY RAIN WILL REMAIN POSSIBLE SUNDAY/MONDAY. THE
MONSOON MOISTURE PLUME...ALBEIT DISJOINTED AT TIMES... WILL REMAIN
OVER PORTIONS OF THE STATE THROUGH THE REST OF THE WEEK. A MORE
CONCENTRATED MOISTURE PLUME WILL BE POSSIBLE NEXT WEEKEND AS A
PACIFIC TROUGH STRENGTHENS AND DEEPENS TO THE WEST OF THE STATE.
&&
.DISCUSSION...
MASSAGED POPS/SKY COVER AND WEATHER HERE AND THERE BUT NO MAJOR
CHANGES. THE OVERALL WEATHER THEME APPEARS TO BE SIMILAR. A LITTLE
LESS STORM COVERAGE WITH THE FOCUS GRADUALLY SHIFTING WESTWARD
TODAY. THE MAIN FOCUS ON SUNDAY STILL APPEARS TO BE ACROSS THE
WESTERN THIRD AND CURRENT POPS REFLECT THAT. THE PACIFIC TROUGH
WILL NUDGE CLOSER TO THE STATE ON MONDAY THUS SHIFTING THE MAIN
MOISTURE PLUME A LITTLE FURTHER EAST. IT APPEARS THAT THE PAC
TROUGH WOULD REFORM OR DEEPEN TO THE WEST TUESDAY AND CONTINUE
INTO NEXT WEEKEND. THIS WOULD PLACE THE MAIN MONSOONAL MOISTURE
PLUME OVER SOME PORTION OF THE STATE DURING THIS PERIOD. THUS AN
ACTIVE PERIOD BUT NOTHING OUT OF THE ORDINARY AT THIS TIME. WILL
BE FOLLOWING THE UPPER HIGH PROGRESSION BECAUSE ONCE IT
CONSOLIDATES/LESS HIGH CENTERS/ AND MOVES EAST OF THE STATE THEN A
JUICIER MOISTURE FLOW SHOULD ENSUE. THAT APPEARS POSSIBLE LATE
WEEKEND OR DURING NEXT WEEKEND.
SOME MODEL DISPCREPANCIES FOR TODAYS POP FORECAST. HRRR IS MUCH
MORE BULLISH ACROSS THE EASTERN PLAINS COMPARED TO THE NAM/GFS.
LATEST WATER VAPOR IMAGERY SHOWS A DRIER AND MORE STABLE AIRMASS
POISED TO THE NORTH OF THE STATE SO WOULD EXPECT SOME OF THIS AIR
TO MAKE IT INTO EASTERN NM AS THE DAY PROGRESSES. DESPITE THIS
IMPACT...DECIDED TO BEEF UP POPS A BIT MORE ACROSS THE EC/SE
PLAINS THANKS TO THE LATEST HRRR FORECAST. EITHER WAY...MAIN FOCUS
WILL BE SHIFTING SLIGHTLY MORE TO THE WEST. STEERING FLOW FOR THE
STORMS APPEARS TO BE PRETTY LIGHT DUE TO THE CLOSE PROXIMITY TO
THE HIGH CENTER. ONE NOTABLE STEERING FLOW DIRECTION WOULD BE THE
NE FLOW ORIGINATING FROM THE SANDIA MTNS. THIS FLOW USUALLY BODES
WELL FOR PORTIONS OF THE ABQ NE HEIGHTS SO FOOTHILL RECREATIONALISTS
SHOULD BE COGNIZANT OF THAT POTENTIAL IMPACT. ALSO BEEFED UP QPF
AND POPS ACROSS THE GILA REGION AND NORTHERN SACRAMENTO MTNS.
SINCE THE CELLS SHOULD TRAVEL SOUTHWARD OVER THE SACS...RESIDENCE
TIME MAY NOT BE ALL THAT MUCH...BUT SOMETHING TO WATCH IN TERMS
OF LOCALIZED FLOODING. LOCALIZED FLOODING ALSO POSSIBLE ACROSS
THE GILA REGION. BASED ON THE LATEST NASASPORT SOIL MOISTURE
IMAGERY...CATRON COUNTY APPEARS TO BE RATHER MOIST AS WELL AS
PORTIONS OF THE CENTRAL MTNS/EAST SLOPES.
NOT A LOT OF SIGNIFICANT CHANGES IN THE LATEST MODELING. THE
INITIAL PAC TROUGH IS EXPECTED TO SHEAR OUT ACROSS THE
NORTHERN/CENTRAL ROCKIES/NORTHERN PLAINS SUNDAY/MONDAY. LOCALLY
HEAVY RAIN AND A DIFFUSE MONSOONAL MOISTURE PLUME WILL FAVOR THE
CONTINENTAL DIVIDE WESTWARD SUNDAY. THEN SHIFT A BIT MORE TO THE
EAST ON MONDAY BASED ON THE INITIAL PAC TROUGH EJECTION.
THE PAC TROUGH WILL DEEPEN TO THE WEST OF THE STATE TUESDAY
THROUGH THE END OF THE WEEK. PRETTY TYPICAL PATTERN FOR
SEPTEMBER...AT LEAST BASED ON THE PAST FEW YEARS. MONSOONAL
MOISTURE WILL TRY TO MOVE NORTHWARD AHEAD OF THE TROUGH AND
CONTINUE SH/TS OVER THE FORECAST AREA. SUBTLE DAY TO DAY CHANGES
WILL DEPEND ON WEAK VORTICE WAVES ORIGINATING FROM MEXICO AS WELL
AS A DRIER AND MORE STABLE AIRMASS ROTATING AROUND THE HIGH
CENTER. IT APPEARS THAT BASED ON THE PAC TROUGH PROGRESSION...THE
UPPER HIGH WOULD EVENTUALLY SHIFT EAST OF THE STATE ALTHOUGH THIS
PROGRESSION WILL MOST LIKELY JUMP AROUND A BIT BECAUSE THE MODELS
HAVE BEEN HAVING A HARDER TIME WITH THE PROGRESSION OF THE PAC
TROUGH ALONG THE WEST COAST. EITHER WAY...WOULD EXPECT THE
MONSOONAL MOISTURE PLUME...ORIGINATING FROM MEXICO...TO BECOME
MORE CONSOLIDATED AROUND THE UPPER HIGH OR BECOMING LESS DIFFUSE.
WILL JUST HAVE TO WAIT ON SEE ON THAT ONE. DECIDED TO INCREASE
TEMPS SLIGHTLY ABOVE MODEL GUIDANCE OR SUPER BLEND LEVELS DURING
THE EXTENDED PERIOD. ALSO LOWERED MIN TEMPS IN THE HIGHER MTN
BASINS SUCH AS THE MORENO VALLEY DUE TO LOWERING DEWPOINTS.
50
&&
.FIRE WEATHER...
BACK DOOR FRONT HAS PUSHED WESTWARD TO THE CONTDVD EARLY THIS
MORNING. THIS WILL SET THE STAGE FOR MORE ACTIVITY ACROSS WESTERN NM
TODAY AS COMPARED TO YESTERDAY...THOUGH WETTING RAINS WILL STILL BE
SPOTTY...WITH THE WEST CENTRAL HIGHLANDS BEING THE EXCEPTION. HI-RES
MODELS STILL SHOWING A FAIR AMOUNT OF ACTIVITY ACROSS THE EASTERN
PLAINS AS WELL...BUT WITH DRIER AIR MOVING IN...IT SHOULD NOT BE AS
WIDESPREAD OR AS ORGANIZED AS YESTERDAY. STORM MOTION LOOKS TO SHIFT
A BIT TODAY...PERHAPS MORE TOWARD THE SOUTHWEST OR WEST ACROSS THE
EAST AND MORE TOWARD THE NORTH ACROSS THE WEST.
THE UPPER HIGH IS STILL ON TRACK TO ELONGATE FROM SW TO NE FROM SE
AZ TO NE NM ON SUNDAY. MEANWHILE...THE CENTROID OF THE MID LEVEL
HIGH WILL SHIFT OVER EASTERN NM OR WEST TEXAS. THIS WILL ALLOW MID
LEVEL MOISTURE TO STREAM NORTHWARD ACROSS FAR WESTERN NM AND EASTERN
AZ. APPEARS THAT THE BEST PRECIP CHANCES WILL BE ACROSS THE WESTERN
THIRD OF THE STATE AND SOME SPOTTY HEAVY RAINFALL WILL BE POSSIBLE.
STORM MOTION WILL GENERALLY BE TOWARD THE NORTHEAST AROUND 5-10 MPH.
THE MOISTURE PLUME STILL LOOKS TO SHIFT EASTWARD ON MONDAY...
FOCUSING THE BEST CHANCE FOR TSTMS FROM THE WEST CENTRAL HIGHLANDS
NEWD TO THE NE PLAINS. STORM MOTION WILL LIKELY BE A BIT MORE
ERRATIC...BUT GENERALLY FROM WEST TO EAST OR SW TO NE.
APPEARS THAT THE MOISTURE PLUME WILL STILL BE HOVERING OVER NM ON
TUESDAY...THOUGH NOT AS ROBUST AS SUNDAY OR MONDAY. WILL STILL LOOK
FOR STORMS...MAINLY OVER THE HIGH TERRAIN.
ECMWF AND CANADIAN MODELS CONTINUE TO SHOW THE UPPER HIGH CENTERED
FARTHER SOUTH WEDNESDAY...ALLOWING FOR DRIER WESTERLY FLOW ACROSS
NORTHERN NM. THE GFS HANGS ONTO A DISORGANIZED PLUME ON WEDNESDAY
WITH THE HIGH OVER WEST TEXAS...THOUGH BY THURSDAY...THE HIGH
WEAKENS ALLOWING THAT DRIER AIR INTO NORTHERN NM. WITH MODEL
INCONSISTENCIES OF LATE...HARD TO HAVE A DEFINITE ANSWER...BUT IT
DOES LOOK LIKE MODELS ARE TRENDING TOWARD A DRIER LATTER HALF OF
NEXT WEEK.
VERY LITTLE TEMPERATURE CHANGES OVER THE NEXT SEVERAL DAYS... WITH
HIGHS GENERALLY AT OR ABOVE NORMAL. HUMIDITIES WILL LOWER WED/THURS
MAINLY ACROSS NORTHERN NM IF THE AFOREMENTIONED PATTERN COMES TO
FRUITION. WEAK TRANSPORT WINDS WILL CONTINUE TO RESULT IN POOR TO
FAIR VENT RATES ACROSS NORTH CENTRAL NM TODAY...BUT SHOULD GENERALLY
IMPROVE INTO THE GOOD TO EXCELLENT RANGE NEXT WEEK. ONE EXCEPTION
MAY BE ACROSS THE SANGRE DE CRISTO MOUNTAINS ON MONDAY.
34
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
341 AM MDT SAT AUG 29 2015
.SYNOPSIS...
STORM COVERAGE WILL LOWER SLIGHTLY TODAY ALTHOUGH LOCALLY HEAVY
RAIN WILL REMAIN POSSIBLE OVER THE MOUNTAINS...ESPECIALLY
SOUTHWEST AND NORTHERN SACRAMENTOS. THE FAVORED STORM COVERAGE
AREAS WILL SHIFT WESTWARD AND FAVOR THE CONTINENTAL DIVIDE TO THE
ARIZONA BORDER ON SUNDAY. A PACIFIC TROUGH WILL NUDGE CLOSER TO
THE STATE ON MONDAY AND SHIFT THE MAIN STORM COVERAGE FURTHER
EAST. LOCALLY HEAVY RAIN WILL REMAIN POSSIBLE SUNDAY/MONDAY. THE
MONSOON MOISTURE PLUME...ALBEIT DISJOINTED AT TIMES... WILL REMAIN
OVER PORTIONS OF THE STATE THROUGH THE REST OF THE WEEK. A MORE
CONCENTRATED MOISTURE PLUME WILL BE POSSIBLE NEXT WEEKEND AS A
PACIFIC TROUGH STRENGTHENS AND DEEPENS TO THE WEST OF THE STATE.
&&
.DISCUSSION...
MASSAGED POPS/SKY COVER AND WEATHER HERE AND THERE BUT NO MAJOR
CHANGES. THE OVERALL WEATHER THEME APPEARS TO BE SIMILAR. A LITTLE
LESS STORM COVERAGE WITH THE FOCUS GRADUALLY SHIFTING WESTWARD
TODAY. THE MAIN FOCUS ON SUNDAY STILL APPEARS TO BE ACROSS THE
WESTERN THIRD AND CURRENT POPS REFLECT THAT. THE PACIFIC TROUGH
WILL NUDGE CLOSER TO THE STATE ON MONDAY THUS SHIFTING THE MAIN
MOISTURE PLUME A LITTLE FURTHER EAST. IT APPEARS THAT THE PAC
TROUGH WOULD REFORM OR DEEPEN TO THE WEST TUESDAY AND CONTINUE
INTO NEXT WEEKEND. THIS WOULD PLACE THE MAIN MONSOONAL MOISTURE
PLUME OVER SOME PORTION OF THE STATE DURING THIS PERIOD. THUS AN
ACTIVE PERIOD BUT NOTHING OUT OF THE ORDINARY AT THIS TIME. WILL
BE FOLLOWING THE UPPER HIGH PROGRESSION BECAUSE ONCE IT
CONSOLIDATES/LESS HIGH CENTERS/ AND MOVES EAST OF THE STATE THEN A
JUICIER MOISTURE FLOW SHOULD ENSUE. THAT APPEARS POSSIBLE LATE
WEEKEND OR DURING NEXT WEEKEND.
SOME MODEL DISPCREPANCIES FOR TODAYS POP FORECAST. HRRR IS MUCH
MORE BULLISH ACROSS THE EASTERN PLAINS COMPARED TO THE NAM/GFS.
LATEST WATER VAPOR IMAGERY SHOWS A DRIER AND MORE STABLE AIRMASS
POISED TO THE NORTH OF THE STATE SO WOULD EXPECT SOME OF THIS AIR
TO MAKE IT INTO EASTERN NM AS THE DAY PROGRESSES. DESPITE THIS
IMPACT...DECIDED TO BEEF UP POPS A BIT MORE ACROSS THE EC/SE
PLAINS THANKS TO THE LATEST HRRR FORECAST. EITHER WAY...MAIN FOCUS
WILL BE SHIFTING SLIGHTLY MORE TO THE WEST. STEERING FLOW FOR THE
STORMS APPEARS TO BE PRETTY LIGHT DUE TO THE CLOSE PROXIMITY TO
THE HIGH CENTER. ONE NOTABLE STEERING FLOW DIRECTION WOULD BE THE
NE FLOW ORIGINATING FROM THE SANDIA MTNS. THIS FLOW USUALLY BODES
WELL FOR PORTIONS OF THE ABQ NE HEIGHTS SO FOOTHILL RECREATIONALISTS
SHOULD BE COGNIZANT OF THAT POTENTIAL IMPACT. ALSO BEEFED UP QPF
AND POPS ACROSS THE GILA REGION AND NORTHERN SACRAMENTO MTNS.
SINCE THE CELLS SHOULD TRAVEL SOUTHWARD OVER THE SACS...RESIDENCE
TIME MAY NOT BE ALL THAT MUCH...BUT SOMETHING TO WATCH IN TERMS
OF LOCALIZED FLOODING. LOCALIZED FLOODING ALSO POSSIBLE ACROSS
THE GILA REGION. BASED ON THE LATEST NASASPORT SOIL MOISTURE
IMAGERY...CATRON COUNTY APPEARS TO BE RATHER MOIST AS WELL AS
PORTIONS OF THE CENTRAL MTNS/EAST SLOPES.
NOT A LOT OF SIGNIFICANT CHANGES IN THE LATEST MODELING. THE
INITIAL PAC TROUGH IS EXPECTED TO SHEAR OUT ACROSS THE
NORTHERN/CENTRAL ROCKIES/NORTHERN PLAINS SUNDAY/MONDAY. LOCALLY
HEAVY RAIN AND A DIFFUSE MONSOONAL MOISTURE PLUME WILL FAVOR THE
CONTINENTAL DIVIDE WESTWARD SUNDAY. THEN SHIFT A BIT MORE TO THE
EAST ON MONDAY BASED ON THE INITIAL PAC TROUGH EJECTION.
THE PAC TROUGH WILL DEEPEN TO THE WEST OF THE STATE TUESDAY
THROUGH THE END OF THE WEEK. PRETTY TYPICAL PATTERN FOR
SEPTEMBER...AT LEAST BASED ON THE PAST FEW YEARS. MONSOONAL
MOISTURE WILL TRY TO MOVE NORTHWARD AHEAD OF THE TROUGH AND
CONTINUE SH/TS OVER THE FORECAST AREA. SUBTLE DAY TO DAY CHANGES
WILL DEPEND ON WEAK VORTICE WAVES ORIGINATING FROM MEXICO AS WELL
AS A DRIER AND MORE STABLE AIRMASS ROTATING AROUND THE HIGH
CENTER. IT APPEARS THAT BASED ON THE PAC TROUGH PROGRESSION...THE
UPPER HIGH WOULD EVENTUALLY SHIFT EAST OF THE STATE ALTHOUGH THIS
PROGRESSION WILL MOST LIKELY JUMP AROUND A BIT BECAUSE THE MODELS
HAVE BEEN HAVING A HARDER TIME WITH THE PROGRESSION OF THE PAC
TROUGH ALONG THE WEST COAST. EITHER WAY...WOULD EXPECT THE
MONSOONAL MOISTURE PLUME...ORIGINATING FROM MEXICO...TO BECOME
MORE CONSOLIDATED AROUND THE UPPER HIGH OR BECOMING LESS DIFFUSE.
WILL JUST HAVE TO WAIT ON SEE ON THAT ONE. DECIDED TO INCREASE
TEMPS SLIGHTLY ABOVE MODEL GUIDANCE OR SUPER BLEND LEVELS DURING
THE EXTENDED PERIOD. ALSO LOWERED MIN TEMPS IN THE HIGHER MTN
BASINS SUCH AS THE MORENO VALLEY DUE TO LOWERING DEWPOINTS.
50
&&
.FIRE WEATHER...
BACK DOOR FRONT HAS PUSHED WESTWARD TO THE CONTDVD EARLY THIS
MORNING. THIS WILL SET THE STAGE FOR MORE ACTIVITY ACROSS WESTERN NM
TODAY AS COMPARED TO YESTERDAY...THOUGH WETTING RAINS WILL STILL BE
SPOTTY...WITH THE WEST CENTRAL HIGHLANDS BEING THE EXCEPTION. HI-RES
MODELS STILL SHOWING A FAIR AMOUNT OF ACTIVITY ACROSS THE EASTERN
PLAINS AS WELL...BUT WITH DRIER AIR MOVING IN...IT SHOULD NOT BE AS
WIDESPREAD OR AS ORGANIZED AS YESTERDAY. STORM MOTION LOOKS TO SHIFT
A BIT TODAY...PERHAPS MORE TOWARD THE SOUTHWEST OR WEST ACROSS THE
EAST AND MORE TOWARD THE NORTH ACROSS THE WEST.
THE UPPER HIGH IS STILL ON TRACK TO ELONGATE FROM SW TO NE FROM SE
AZ TO NE NM ON SUNDAY. MEANWHILE...THE CENTROID OF THE MID LEVEL
HIGH WILL SHIFT OVER EASTERN NM OR WEST TEXAS. THIS WILL ALLOW MID
LEVEL MOISTURE TO STREAM NORTHWARD ACROSS FAR WESTERN NM AND EASTERN
AZ. APPEARS THAT THE BEST PRECIP CHANCES WILL BE ACROSS THE WESTERN
THIRD OF THE STATE AND SOME SPOTTY HEAVY RAINFALL WILL BE POSSIBLE.
STORM MOTION WILL GENERALLY BE TOWARD THE NORTHEAST AROUND 5-10 MPH.
THE MOISTURE PLUME STILL LOOKS TO SHIFT EASTWARD ON MONDAY...
FOCUSING THE BEST CHANCE FOR TSTMS FROM THE WEST CENTRAL HIGHLANDS
NEWD TO THE NE PLAINS. STORM MOTION WILL LIKELY BE A BIT MORE
ERRATIC...BUT GENERALLY FROM WEST TO EAST OR SW TO NE.
APPEARS THAT THE MOISTURE PLUME WILL STILL BE HOVERING OVER NM ON
TUESDAY...THOUGH NOT AS ROBUST AS SUNDAY OR MONDAY. WILL STILL LOOK
FOR STORMS...MAINLY OVER THE HIGH TERRAIN.
ECMWF AND CANADIAN MODELS CONTINUE TO SHOW THE UPPER HIGH CENTERED
FARTHER SOUTH WEDNESDAY...ALLOWING FOR DRIER WESTERLY FLOW ACROSS
NORTHERN NM. THE GFS HANGS ONTO A DISORGANIZED PLUME ON WEDNESDAY
WITH THE HIGH OVER WEST TEXAS...THOUGH BY THURSDAY...THE HIGH
WEAKENS ALLOWING THAT DRIER AIR INTO NORTHERN NM. WITH MODEL
INCONSISTENCIES OF LATE...HARD TO HAVE A DEFINITE ANSWER...BUT IT
DOES LOOK LIKE MODELS ARE TRENDING TOWARD A DRIER LATTER HALF OF
NEXT WEEK.
VERY LITTLE TEMPERATURE CHANGES OVER THE NEXT SEVERAL DAYS... WITH
HIGHS GENERALLY AT OR ABOVE NORMAL. HUMIDITIES WILL LOWER WED/THURS
MAINLY ACROSS NORTHERN NM IF THE AFOREMENTIONED PATTERN COMES TO
FRUITION. WEAK TRANSPORT WINDS WILL CONTINUE TO RESULT IN POOR TO
FAIR VENT RATES ACROSS NORTH CENTRAL NM TODAY...BUT SHOULD GENERALLY
IMPROVE INTO THE GOOD TO EXCELLENT RANGE NEXT WEEK. ONE EXCEPTION
MAY BE ACROSS THE SANGRE DE CRISTO MOUNTAINS ON MONDAY.
34
&&
.AVIATION...
06Z TAF CYCLE
CONVECTION IS EXPECTED TO CONTINUE TO DIMINISH
THROUGH THE LATE NIGHT HOURS. A BACK DOOR COLD FRONT WILL FINISH
PUSHING THROUGH W AREAS TONIGHT INCREASING HUMIDITIES THERE FOR
SATURDAY. TS WILL FAVOR THE CONTDVD AND CENTRAL MT CHAIN SATURDAY.
MODELS ARE COMING INTO BETTER AGREEMENT ON A N TO S MOVEMENT OF
STORMS ON SATURDAY...WHICH MATCHES WHAT GENERALLY OCCURRED TODAY.
AIRPORTS NEAR MTS HAVE THE BEST CHANCE OF GETTING HIT BY TS/SHRA
SATURDAY AFTN AND EVENING...ESPECIALLY KSAF. &&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 90 61 88 59 / 5 10 20 40
DULCE........................... 83 50 84 50 / 30 10 10 50
CUBA............................ 82 52 83 52 / 40 20 30 30
GALLUP.......................... 86 54 84 53 / 20 20 60 50
EL MORRO........................ 82 52 80 51 / 20 40 40 40
GRANTS.......................... 83 53 82 53 / 20 50 40 50
QUEMADO......................... 83 53 81 55 / 20 40 30 50
GLENWOOD........................ 87 59 84 60 / 40 30 40 50
CHAMA........................... 76 48 77 48 / 50 20 10 40
LOS ALAMOS...................... 81 57 82 57 / 30 20 40 30
PECOS........................... 79 53 81 55 / 50 20 20 10
CERRO/QUESTA.................... 79 49 81 50 / 40 20 10 10
RED RIVER....................... 68 41 71 43 / 50 20 20 10
ANGEL FIRE...................... 72 43 75 45 / 50 20 10 10
TAOS............................ 81 49 82 51 / 10 10 5 10
MORA............................ 75 50 80 53 / 50 20 20 10
ESPANOLA........................ 86 54 87 55 / 20 10 10 20
SANTA FE........................ 82 56 83 57 / 40 20 5 10
SANTA FE AIRPORT................ 85 57 86 58 / 20 20 5 10
ALBUQUERQUE FOOTHILLS........... 87 62 88 63 / 50 30 5 10
ALBUQUERQUE HEIGHTS............. 87 65 88 66 / 20 20 5 10
ALBUQUERQUE VALLEY.............. 89 62 90 63 / 10 20 5 10
ALBUQUERQUE WEST MESA........... 88 63 89 64 / 10 20 5 10
LOS LUNAS....................... 90 61 91 62 / 10 20 5 10
RIO RANCHO...................... 87 61 89 63 / 10 20 5 10
SOCORRO......................... 89 61 89 63 / 10 20 5 20
SANDIA PARK/CEDAR CREST......... 83 59 84 59 / 50 30 20 20
TIJERAS......................... 85 58 86 59 / 50 20 10 20
MORIARTY/ESTANCIA............... 83 53 85 54 / 20 10 5 10
CLINES CORNERS.................. 81 55 82 57 / 20 10 5 5
GRAN QUIVIRA.................... 83 57 84 59 / 20 20 5 10
CARRIZOZO....................... 85 59 85 61 / 30 10 5 10
RUIDOSO......................... 76 55 78 58 / 50 20 5 10
CAPULIN......................... 82 53 86 56 / 10 5 0 0
RATON........................... 85 52 88 55 / 10 5 0 10
SPRINGER........................ 85 54 88 56 / 10 5 0 10
LAS VEGAS....................... 80 52 83 55 / 20 10 5 5
CLAYTON......................... 87 60 91 62 / 5 5 0 5
ROY............................. 85 56 88 58 / 10 5 0 5
CONCHAS......................... 91 63 93 64 / 10 5 0 5
SANTA ROSA...................... 89 60 91 63 / 10 5 0 5
TUCUMCARI....................... 92 62 94 65 / 10 5 0 0
CLOVIS.......................... 89 61 91 63 / 20 5 0 0
PORTALES........................ 90 60 92 64 / 20 10 0 0
FORT SUMNER..................... 91 63 92 63 / 10 5 0 5
ROSWELL......................... 92 65 95 65 / 20 10 0 5
PICACHO......................... 86 59 88 61 / 20 10 0 10
ELK............................. 81 57 82 58 / 40 20 0 10
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
50
AREA FORECAST DISCUSSION
NWS RALEIGH NC
200 PM EDT SAT AUG 29 2015
.SYNOPSIS...SURFACE HIGH PRESSURE REMAINS OVER MUCH OF THE REGION
FOR THE REST OF THE WEEKEND. AN UPPER LEVEL DISTURBANCE MOVES FROM
THE NORTHERN GULF OF MEXICO ACROSS THE WESTERN CAROLINAS SUNDAY
THROUGH EARLY MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 905 AM SATURDAY...
WHILE THE LATEST SURFACE ANALYSIS SHOWED HIGH PRESSURE OVER CENTRAL
NORTH CAROLINA...AND SPC MESOANALYSIS DATA SHOWED LOW PRECIPITABLE
WATER VALUES WITH AN 850MB RIDGE IN PLACE AND LIMITED 850MB MOISTURE
ADVECTION...MID- AND HIGH-LEVEL CLOUDS WERE SPREADING OVER CENTRAL
NORTH CAROLINA FROM THE SOUTH. THE LATEST WATER VAPOR IMAGES
INDICATED THE INCREASE OF THE MID-LEVEL MOISTURE WELL...STREAMING
NORTH AHEAD OF AN UPPER LOW OVER THE NORTHERN GULF. THE CANADIAN
CLOUD COVER MODEL...WHICH SEEMED TO HAVE A GOOD HANDLE ON THE CLOUD
COVER...SPREADS HIGH-LEVEL CLOUDS OVER CENTRAL NORTH CAROLINA FROM
THE SOUTHWEST DURING THE DAY...WITH NUMEROUS CLOUDS EXPECTED EVEN
OVER THE NORTHERN COASTAL PLAIN BY 18Z TO 20Z.
EARLY MORNING VISIBLE IMAGES SUGGESTS THE INITIAL SURGE OF HIGH
CLOUDS IS SOMEWHAT THIN...WHICH MAY PROVIDE FOR TIME FOR
TEMPERATURES TO RECOVER. AS SUN BECOMES MORE FILTERED OVER TIME WITH
LIKELY A GREATER DEGREE OF OPAQUE UPPER-LEVEL CLOUDS...THE EFFECT
SHOULD DAMPEN THE TEMPERATURE RISE. STILL...DID NOT LOWER MAXES TOO
MUCH...ONLY ABOUT A DEGREE OR SO...AS THERE MAY BE ENOUGH THIN SPOTS
TO GET WARMING SUFFICIENT FOR ABOUT 10 TO 15 DEGREES OF TEMPERATURE
INCREASE BEYOND THIS WRITING AT AN EARLY SUN TIME. RAP MODEL
SOUNDINGS SHOW MOISTENING ONLY ALOFT...WITH DRY AIR BELOW 500MB AND
A VERY CAPPED AIR MASS.
TONIGHT...MID-HIGH LEVEL CLOUDS WILL THICKEN IN RESPONSE TO THE
APPROACH OF THE NORTHERN GULF S/W THOUGH LIFT TO GENERATE ANY
SHOWERS APPEARS TO BE LACKING. WEAK (EMPHASIS ON WEAK) LOW LEVEL
ISENTROPIC LIFT MAY GENERATE A SHOWER OR SPRINKLES AROUND DAYBREAK
OVER THE FAR SOUTHERN PIEDMONT. THE INCREASING CLOUDINESS AND A
MODIFYING AIR MASS WILL YIELD MIN TEMPS A FEW DEGREES WARMER THAN
LOW TEMPS EXPECTED THIS MORNING. MIN TEMPS MID 60S NORTH TO THE
UPPER 60S SOUTH.
&&
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 333 AM SATURDAY...
HAVE TRENDED FORECAST THIS PERIOD A LITTLE WETTER...ESPECIALLY
SUNDAY NIGHT ACROSS THE PIEDMONT AND SANDHILLS.
ATMOSPHERE WILL CONTINUE TO MOISTEN AS NORTHERN GULF SYSTEM LIFTS
NEWD ACROSS GA AND INTO THE SOUTHERN APPALACHIANS LATE IN THE DAY.
THE APPROACH OF THIS SYSTEM WILL INDUCE A LOW LEVEL SELY
FLOW...RESULTING IN AN UPSLOPE COMPONENT TO THE LOW LEVEL FLOW OVER
THE SOUTHERN-WESTERN PIEDMONT. THE GFS SOLUTION IS A BIT MORE
AGGRESSIVE WITH THIS SCENARIO COMPARED TO THE NAM WHILE THE 00Z
ECMWF FAVORS THE GFS SOLUTION. INCREASING UPPER DIVERGENCE BY SUNDAY
AFTERNOON IN CONJUNCTION WITH A SLIGHTLY UNSTABLE AND INCREASINGLY
MOIST AIR MASS SHOULD SUPPORT THE DEVELOPMENT OF A FEW SHOWERS AND
AN ISOLATED STORM...MAINLY ACROSS PORTIONS OF THE SOUTHERN PIEDMONT
AND THE SANDHILLS. MAY SEE ADDITIONAL COVERAGE OVER THE
SANDHILLS/SOUTHERN COASTAL PLAIN DUE TO THE INLAND MOVING SEABREEZE.
THUS...WILL INCREASE POPS BIT FROM THE PREVIOUS FORECAST...UP TO 40
PERCENT OVER THE SOUTH AND WEST SECTIONS BY LATE IN THE DAY/SUNDAY
EVENING.
DUE TO EXPECTED EXTENSIVE CLOUDINESS...HAVE ADJUSTED MAX TEMPS DOWN
A BIT OVER THE WEST AND SW...WITH LITTLE CHANGE ELSEWHERE. IF CLOUDS
ARE LOWER/THICKER THAN EXPECTED OR SHOWER COVERAGE MORE EXTENSIVE BY
AFTERNOON...MAX TEMPS MAY END UP BEING 3-4 DEGREES COOLER THAN
FORECAST EVERYWHERE.
SUNDAY NIGHT...S/W LIFTS NEWD IMMEDIATELY WEST OF OUR REGION LATE IN
THE NIGHT...MAXIMIZING UPPER DIVERGENCE. IN THE 850-700MB LAYER WEAK
SPEED CONVERGENCE IN THE MOIST LAYER. THUS...SHOULD SEE A THREAT FOR
A FEW SHOWERS THROUGHOUT THE NIGHT...MAINLY ACROSS THE PIEDMONT. MIN
TEMPS MAINLY IN THE UPPER 60S TO NEAR 70.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 355 AM SATURDAY...
THE MODELS ARE IN BETTER AGREEMENT TODAY REGARDING THE
EJECTION/PROGRESSION OF A SHORTWAVE TROUGH --INITIALLY A CLOSED LOW
OVER THE CENTRAL GULF COAST THIS MORNING-- FROM THE CENTRAL
APPALACHIANS TO THE MIDDLE ATLANTIC COAST ON MON. MEANWHILE...AN
UPSTREAM KICKER SHORTWAVE TROUGH WILL AMPLIFY INTO THE SOUTHERN
PLAINS TO LOWER AND MID MS VALLEY AND RE-CARVE THE TROUGH
WESTWARD...AND CONSEQUENTLY ALLOW THE SUB-TROPICAL RIDGE TO BULGE
WESTWARD INTO THE SOUTHEAST US. A STRONGLY POSITIVELY-TILTED SHEAR
AXIS WILL SEPARATE THE SOUTHEASTERN RIDGE AND ANOTHER FORECAST TO
BUILD ACROSS THE OH VALLEY AND GREAT LAKES...AND THIS FEATURE WILL
INITIALLY DRAW TROPICAL MOISTURE ASSOCIATED WITH (AND IN ADVANCE OF)
ERIKA...NORTHWARD THROUGH THE CAROLINAS EARLY NEXT WEEK.
THEREAFTER...MOISTURE FROM (AND THE OVERALL INFLUENCE OF)
ERIKA...WILL BE DEPENDENT ON HOW ERIKA EVOLVES DURING THE NEXT
SEVERAL DAYS...WHICH IS A RELATIVELY LOW CONFIDENCE FORECAST.
THE ENVELOPE OF GUIDANCE SOLUTIONS HAS CONTINUED A WESTWARD TREND
WITH THE TRACK OF WHAT BECOMES OF ERIKA...WITH THE PREFERRED NHC
TRACK NOW THROUGH THE EASTERN GULF OF MEXICO/ALONG THE WEST COAST OF
FL EARLY NEXT WEEK...TO A POSITION NEAR THE FL PANHANDLE OR SOUTHERN
GA BY WED. CONSIDERABLE FORECAST UNCERTAINTY REMAINS WITH ERIKA...
HOWEVER...SINCE THE CIRCULATION MAY DISSIPATE ALTOGETHER DUE TO THE
INTERACTION WITH BOTH LAND AND A HOSTILE WIND SHEAR ENVIRONMENT
DURING THE NEXT 24-36 HOURS. OR IF IT SURVIVES... REGENERATION/
STRENGTHENING WILL BE POSSIBLE OVER THE WARM WATERS AND IN A
WEAKENING WIND SHEAR ENVIRONMENT OVER THE FL STRAITS AND EASTERN GOM.
REGARDLESS...IT STILL APPEARS THAT THE LOW LEVEL VORTICITY
CENTER...IN WHATEVER STATE IT MAY BE BY THE MIDDLE OF NEXT
WEEK...WILL LIKELY BE SUPPRESSED MOSTLY SOUTH AND/OR WEST OF CENTRAL
NC BY THE MERGING OF THE AFOREMENTIONED RIDGES ALOFT FROM THE GREAT
LAKES TO THE SE COAST. AS SUCH...OUR SENSIBLE WEATHER WILL LIKELY
INSTEAD BE INFLUENCED INDIRECTLY BY ASSOCIATED MOISTURE STREAMING
NNE ALONG THE AFOREMENTIONED SHEAR AXIS...WHICH WOULD RESULT IN BOTH
VARIABLY CLOUDY CONDITIONS AND SUPPORT FOR SLIGHTLY ABOVE CLIMO
PRECIPITATION CHANCES - HIGHEST SOUTH IN CLOSEST PROXIMITY TO THE
REMNANTS OF ERIKA. TEMPERATURES SHOULD BE CLOSE TO CLIMO - PERHAPS A
LITTLE BELOW /ABOVE FOR HIGHS/LOWS DEPENDING ON TIMING AND EXTENT OF
MOISTURE/CLOUD COVER.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 200 PM SATURDAY...
VFR CONDITIONS ARE EXPECTED THROUGH THE 18Z VALID TAF PERIOD.
SURFACE WINDS SUSTAINED UNDER 10KT SHOULD GRADUALLY VEER. SOUTHERLY
SURFACE WINDS SHOULD BE LIKELY BY MID-MORNING SUNDAY. THE GUIDANCE
CONSENSUS SUGGESTS A MORE VARIABLE SURFACE WIND TOWARD KFAY EARLY
SUNDAY MORNING...POSSIBLY EVEN A PERIOD OF A LIGHT NORTHWEST WIND...
BEFORE MIXING THERE RESULTS IN A SOUTHERLY WIND BY LATE SUNDAY
MORNING.
AN UPPER-LEVEL LOW OVER THE NORTHERN GULF OF MEXICO IS FORECAST BY
BOTH THE NAM AND GFS MODELS TO WEAKEN SOME WHILE LIFTING SLOWLY
NORTH...MOVING OVER THE WESTERN CAROLINAS LATE SUNDAY THROUGH EARLY
MONDAY. A DRY AIR MASS UNDER SURFACE HIGH PRESSURE AHEAD OF THE
UPPER LOW SHOULD KEEP ANY PRECIPITATION THAT OCCURS LIGHT WITH
CONDITIONS VFR. SHOULD MID- AND UPPER-LEVEL DRYING OCCUR LATE SUNDAY
NIGHT AS INDICATED BY THE NAM AND GFS MODEL SOUNDINGS...AREAS OF SUB-
VFR CONDITIONS IN LOW CLOUDS AND FOG WOULD OCCUR PRIOR TO DAWN
MONDAY IN MOIST LOW-LEVEL AIR. FROM MONDAY AFTERNOON INTO
THURSDAY...IN A MOIST AIR MASS AND MODEST INSTABILITY...AVIATION
INTERESTS CAN CURRENTLY ANTICIPATE WIDELY SCATTERED TO SCATTERED
SHOWERS AND THUNDERSTORMS WITH THEIR ASSOCIATED SUB-VFR
CONDITIONS...ALONG WITH THE POTENTIAL OF LATE NIGHT AND EARLY
MORNING AREAS OF LOW CLOUDS AND FOG.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...DJF/WSS
SHORT TERM...WSS
LONG TERM...26
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
132 PM EDT SAT AUG 29 2015
.SYNOPSIS...
HIGH PRESSURE OVER THE MID-ATLANTIC REGION WILL BRING FAIR
WEATHER THROUGH TODAY. INCREASING MOISTURE FROM THE GULF OF
MEXICO COULD BRING SHOWERS AND ISOLATED THUNDERSTORMS TO THE AREA
SUNDAY INTO MONDAY. THE REMNANTS OF ERIKA WILL APPROACH FLORIDA
EARLY NEXT WEEK...POSSIBLY TRACKING INTO THE NORTHERN GULF OF MEXICO
AFTERWARD.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM SATURDAY...A RATHER NICE SATURDAY FORECAST AS LONG AS
ONE DOESN`T MIND THE SUNLIGHT BEING INCREASINGLY FILTERED BY A
GROWING CANOPY OF CIRRUS. THE DEWPOINT HAS CREPT UP FROM YESTERDAY
AND THE HRRR HAD BEEN SUGGESTING THAT A FEW SHOWERS MATERIALIZE OVER
FAR SOUTHERN COUNTIES. SUCCESSIVE RUNS HAVE BACKED OFF ON THIS SO
WILL KEEP THE FORECAST DRY AT THIS TIME-ANYTHING THAT FALLS SHOULD
BE NON-MEASURABLE SPRINKLES.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 3 AM SATURDAY...HIGH PRESSURE WILL BASICALLY DISSIPATE
ACROSS THE AREA SUNDAY AS MID LEVEL LOW PRESSURE...CURRENTLY OVER
THE GULF COAST RAMBLES INTO THE UPSTATE SOUTH CAROLINA REGION.
THIS FEATURE COMBINED WITH THE ANTICYCLONIC FLOW AROUND THE
BERMUDA RIDGE WILL ADVECT MOISTURE LADEN AIR INTO THE REGION. SOME
DIFLUENCE IS ALSO NOTED IN THE AREA. AS PRECIPITABLE WATERS RISE
TO ALMOST TWO INCHES...LOW CHANCE POPS ARE IN THE PICTURE MAINLY
ACROSS SOUTH CAROLINA SUNDAY AND AREA WIDE MONDAY. TEMPERATURES
ARE MOSTLY SEASONABLE WITH HIGHS IN THE MID TO UPPER 80S AND LOWS
IN THE LOWER TO MIDDLE 70S.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 3 AM SATURDAY...EXPECT A DIFFUSE MID LEVEL PATTERN DURING THE
EXTENDED PERIOD WITH A SIMILAR PRESSURE PATTERN. OVERALL THE AREA
REMAINS BETWEEN ATLANTIC RIDGING AND HIGH PRESSURE OUT WEST. WHAT
EVENTUALLY REMAINS OF TROPICAL STORM ERIKA MEANDERS AROUND THE
SOUTHEAST AS A VORT CENTER SEEMINGLY NEVER GOING ANYWHERE. THERMAL
PROFILES REMAIN MOIST HOWEVER AND WITH THE USUAL MESOSCALE
FEATURES...DECENT CHANCE POPS ARE IN THE FORECAST EACH DAY. NO
CHANGES TO THE TEMPERATURE FORECAST WITH READINGS NEAR NORMAL FOR
DAYTIME HIGHS AND SLIGHTLY ABOVE FOR OVERNIGHT LOWS.
&&
.AVIATION /12Z SATURDAY THROUGH THURSDAY/...
AS OF 18Z...MOISTURE STREAMING INTO THE AREA FROM THE SOUTH MAINLY
CONFINED TO THE CIRRUS LEVEL MOST OF THE NIGHT. WILL SHOW LOWERING
CEILINGS TOWARDS DAYBREAK, MOST PRONOUNCED OVER SOUTH CAROLINA. WILL
CAP THE FALL TO MVFR THOUGH SOME OF THE MORE AGGRESSIVE MODELS DO
FALL TO IFR AT MYR, CRE, AND EVEN ILM. AT TIME FEEL THIS IS OVERDONE
BUT NEXT SHIFT MAY BE ABLE TO REFINE. WILL ALSO CARRY VCSH TOWARDS
DAYBREAK ALONG SC COAST BUT THE RAIN ITSELF NOT EXPECTED TO LOWER
ANY FLIGHT CATEGORIES AS IT WILL BE QUITE LIGHT.
EXTENDED OUTLOOK...PREDOMINATELY VFR WITH ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS THROUGH THE EXTENDED. BRIEF MORNING
FOG/STRATUS IS ALSO EXPECTED EACH DAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM SATURDAY...STILL RATHER
CHOPPY AND WILL LEAVE SCEC AS-IS IN THE CONTINUED MODERATE
NORTHEASTERLY GRADIENT. NO CHANGES TO THE FORECAST AND THE PREVIOUS
DISCUSSION FOLLOWS.
AS OF 630 AM SATURDAY...HAVE RAISED A SMALL CRAFT EXERCISE
CAUTION FLAG FOR ALL WATERS...EXCEPT BETWEEN LITTLE RIVER INLET TO
MURRELLS INLET WHERE ITS SOMEWHAT PROTECTED FROM THE HIGHER NE
WIND WAVES DUE TO THE LOWER FETCH FOR THEM TO GROW.
THE MODEST 1020+ HIGH BROADLY CENTERED FROM OVER THE NC-VA BORDER
TO ACROSS THE MID-ATLANTIC STATES...IS PROGGED TO REMAIN
RELATIVELY IN PLACE THRU THIS NEAR TERM PERIOD. AT THIS SAME
TIME...A WEAK SFC LOW IS PROGGED BY THE MODELS ALONG A STALLED SFC
BOUNDARY ORIENTED NE-SW OFF THE CAROLINA COASTLINES THIS
MORNING...THAT WILL TRACK NE ALONG THIS STALLED FRONT TO A
POSITION OFF CAPE HATTERAS BY DAYBREAK SUNDAY. THE AREA WATERS IS
ALREADY EXPERIENCING A TIGHTENED SFC PG ATTM...AND SHOULD REMAIN
THIS WAY TODAY INTO THIS EVENING PRIOR TO THE LOW EXITING NE OF
THE AREA WATERS. AS A RESULT...THE WATERS WILL OBSERVE A SOLID NE
TO ENE 15 TO 20 KT WIND TODAY...THAT WILL SLOWLY SUBSIDE TO 10-15
KT THIS EVENING AND OVERNIGHT.
SIGNIFICANT SEAS HAVE ALREADY RISEN FROM THE INCREASED NE WINDS
FROM YESTERDAY. WILL BE LOOKING AT A SOLID 3 TO 5 FT INTO EARLY
THIS EVENING...BEFORE DROPPING OFF TO BETWEEN 2 TO 4 FT LATER
TONIGHT. THE EXCEPTION WILL BE THE WATERS BETWEEN LITTLE RIVER
INLET TO MURRELLS INLET WHERE A LIMITED FETCH WILL EXIST FOR
GROWING NE WIND-DRIVEN WAVES. AN UNDERLYING 1 TO 1.5 FOOT ESE
GROUND SWELL AT 10-12 SECOND PERIODS WILL CONTINUE...HOWEVER
THE 4 TO 6 SECOND PERIOD WIND DRIVEN WAVES WILL DOMINATE THE
SIGNIFICANT SEAS SPECTRUM.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 3 AM SATURDAY...THE NORTHEAST FLOW WILL GIVE WAY TO A
SOUTHEAST FLOW BY MIDDAY SUNDAY AS HIGH PRESSURE GIVES WAY TO
WEAK COASTAL TROUGHING. THE SOUTHEAST FLOW WILL CONTINUE THROUGH
THE END OF THE PERIOD. GUIDANCE IS HINTING AT A FEW HOURS OF NE
WINDS EARLY TUESDAY BUT THIS SHOULD BE FLEETING. SIGNIFICANT SEAS
WILL GENERALLY BE 2-3 FEET.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 3 AM SATURDAY...RELATIVELY LIGHT WIND FIELDS FOR THE WATERS
WITH WEAK SYNOPTIC FEATURES. OVERALL EXPECT A MOSTLY SOUTHEAST
WIND DIRECTION WITH SPEEDS TEN KNOTS OR LESS. SIGNIFICANT SEAS
WILL BE LIMITED AS WELL WITH 1-3 FEET.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SHK
NEAR TERM...MBB
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...MBB
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1026 AM EDT SAT AUG 29 2015
.SYNOPSIS...
HIGH PRESSURE OVER THE MID-ATLANTIC REGION WILL BRING FAIR
WEATHER THROUGH TODAY. INCREASING MOISTURE FROM THE GULF OF
MEXICO COULD BRING SHOWERS AND ISOLATED THUNDERSTORMS TO THE
AREA SUNDAY INTO MONDAY. ERIKA...OR THE REMNANTS OF ERIKA...WILL
APPROACH FLORIDA EARLY NEXT WEEK...POSSIBLY TRACKING INTO THE
NORTHERN GULF OF MEXICO AFTERWARD.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM SATURDAY...A RATHER NICE SATURDAY FORECAST AS LONG AS
ONE DOESN`T MIND THE SUNLIGHT BEING INCREASINGLY FILTERED BY A
GROWING CANOPY OF CIRRUS. THE DEWPOINT HAS CREPT UP FROM YESTERDAY
AND THE HRRR HAD BEEN SUGGESTING THAT A FEW SHOWERS MATERIALIZE OVER
FAR SOUTHERN COUNTIES. SUCCESSIVE RUNS HAVE BACKED OFF ON THIS SO
WILL KEEP THE FORECAST DRY AT THIS TIME-ANYTHING THAT FALLS SHOULD
BE NON-MEASUREABLE SPRINKLES.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 3 AM SATURDAY...HIGH PRESSURE WILL BASICALLY DISSIPATE
ACROSS THE AREA SUNDAY AS MID LEVEL LOW PRESSURE...CURRENTLY OVER
THE GULF COAST RAMBLES INTO THE UPSTATE SOUTH CAROLINA REGION.
THIS FEATURE COMBINED WITH THE ANTICYCLONIC FLOW AROUND THE
BERMUDA RIDGE WILL ADVECT MOISTURE LADEN AIR INTO THE REGION. SOME
DIFLUENCE IS ALSO NOTED IN THE AREA. AS PRECIPITABLE WATERS RISE
TO ALMOST TWO INCHES...LOW CHANCE POPS ARE IN THE PICTURE MAINLY
ACROSS SOUTH CAROLINA SUNDAY AND AREA WIDE MONDAY. TEMPERATURES
ARE MOSTLY SEASONABLE WITH HIGHS IN THE MID TO UPPER 80S AND LOWS
IN THE LOWER TO MIDDLE 70S.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 3 AM SATURDAY...EXPECT A DIFFUSE MID LEVEL PATTERN DURING THE
EXTENDED PERIOD WITH A SIMILAR PRESSURE PATTERN. OVERALL THE AREA
REMAINS BETWEEN ATLANTIC RIDGING AND HIGH PRESSURE OUT WEST. WHAT
EVENTUALLY REMAINS OF TROPICAL STORM ERIKA MEANDERS AROUND THE
SOUTHEAST AS A VORT CENTER SEEMINGLY NEVER GOING ANYWHERE. THERMAL
PROFILES REMAIN MOIST HOWEVER AND WITH THE USUAL MESOSCALE
FEATURES...DECENT CHANCE POPS ARE IN THE FORECAST EACH DAY. NO
CHANGES TO THE TEMPERATURE FORECAST WITH READINGS NEAR NORMAL FOR
DAYTIME HIGHS AND SLIGHTLY ABOVE FOR OVERNIGHT LOWS.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
AS OF 12Z...HIGH PRESSURE WILL STAY IN CONTROL FOR THE NEXT
24 HOURS WITH HIGH CONFIDENCE FOR VFR CONDITIONS THROUGH THE
FORECAST PERIOD. A BROAD AREA OF LOW PRESSURE CENTERED OVER THE
ALABAMA/MISSISSIPPI BORDER WILL TRY TO BRING UP MOISTURE FROM
THE SOUTH...BUT IT WILL LIKELY NOT MAKE IT FAR ENOUGH NORTHWARD
TO GIVE US ANY WEATHER. LOOK FOR PREDOMINATELY NORTHEAST FLOW
TODAY.
EXTENDED OUTLOOK...PREDOMINATELY VFR WITH ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS THROUGH THE EXTENDED. BRIEF MORNING
FOG/STRATUS IS ALSO EXPECTED EACH DAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM SATURDAY...STILL RATHER
CHOPPY AND WILL LEAVE SCEC AS-IS IN THE CONTINUED MODERATE
NORTHEASTERLY GRADIENT. NO CHANGES TO THE FORECAST AND THE PREVIOUS
DISCUSSION FOLLOWS.
AS OF 630 AM SATURDAY...HAVE RAISED A SMALL CRAFT EXERCISE
CAUTION FLAG FOR ALL WATERS...EXCEPT BETWEEN LITTLE RIVER INLET TO
MURRELLS INLET WHERE ITS SOMEWHAT PROTECTED FROM THE HIGHER NE
WIND WAVES DUE TO THE LOWER FETCH FOR THEM TO GROW.
THE MODEST 1020+ HIGH BROADLY CENTERED FROM OVER THE NC-VA BORDER
TO ACROSS THE MID-ATLANTIC STATES...IS PROGGED TO REMAIN
RELATIVELY IN PLACE THRU THIS NEAR TERM PERIOD. AT THIS SAME
TIME...A WEAK SFC LOW IS PROGGED BY THE MODELS ALONG A STALLED SFC
BOUNDARY ORIENTED NE-SW OFF THE CAROLINA COASTLINES THIS
MORNING...THAT WILL TRACK NE ALONG THIS STALLED FRONT TO A
POSITION OFF CAPE HATTERAS BY DAYBREAK SUNDAY. THE AREA WATERS IS
ALREADY EXPERIENCING A TIGHTENED SFC PG ATTM...AND SHOULD REMAIN
THIS WAY TODAY INTO THIS EVENING PRIOR TO THE LOW EXITING NE OF
THE AREA WATERS. AS A RESULT...THE WATERS WILL OBSERVE A SOLID NE
TO ENE 15 TO 20 KT WIND TODAY...THAT WILL SLOWLY SUBSIDE TO 10-15
KT THIS EVENING AND OVERNIGHT.
SIGNIFICANT SEAS HAVE ALREADY RISEN FROM THE INCREASED NE WINDS
FROM YESTERDAY. WILL BE LOOKING AT A SOLID 3 TO 5 FT INTO EARLY
THIS EVENING...BEFORE DROPPING OFF TO BETWEEN 2 TO 4 FT LATER
TONIGHT. THE EXCEPTION WILL BE THE WATERS BETWEEN LITTLE RIVER
INLET TO MURRELLS INLET WHERE A LIMITED FETCH WILL EXIST FOR
GROWING NE WIND-DRIVEN WAVES. AN UNDERLYING 1 TO 1.5 FOOT ESE
GROUND SWELL AT 10-12 SECOND PERIODS WILL CONTINUE...HOWEVER
THE 4 TO 6 SECOND PERIOD WIND DRIVEN WAVES WILL DOMINATE THE
SIGNIFICANT SEAS SPECTRUM.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 3 AM SATURDAY...THE NORTHEAST FLOW WILL GIVE WAY TO A
SOUTHEAST FLOW BY MIDDAY SUNDAY AS HIGH PRESSURE GIVES WAY TO
WEAK COASTAL TROUGHING. THE SOUTHEAST FLOW WILL CONTINUE THROUGH
THE END OF THE PERIOD. GUIDANCE IS HINTING AT A FEW HOURS OF NE
WINDS EARLY TUESDAY BUT THIS SHOULD BE FLEETING. SIGNIFICANT SEAS
WILL GENERALLY BE 2-3 FEET.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 3 AM SATURDAY...RELATIVELY LIGHT WIND FIELDS FOR THE WATERS
WITH WEAK SYNOPTIC FEATURES. OVERALL EXPECT A MOSTLY SOUTHEAST
WIND DIRECTION WITH SPEEDS TEN KNOTS OR LESS. SIGNIFICANT SEAS
WILL BE LIMITED AS WELL WITH 1-3 FEET.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SHK
NEAR TERM...MBB
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...43
AREA FORECAST DISCUSSION
NWS RALEIGH NC
907 AM EDT SAT AUG 29 2015
.SYNOPSIS...HIGH PRESSURE CONTINUES TO EXTEND OVER THE AREA FROM THE
NORTH TODAY. AN UPPER LEVEL DISTURBANCE WILL MOVE NORTH ALONG THE
APPALACHIANS ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 905 AM SATURDAY...
WHILE THE LATEST SURFACE ANALYSIS SHOWED HIGH PRESSURE OVER CENTRAL
NORTH CAROLINA...AND SPC MESOANALYSIS DATA SHOWED LOW PRECIPITABLE
WATER VALUES WITH AN 850MB RIDGE IN PLACE AND LIMITED 850MB MOISTURE
ADVECTION...MID- AND HIGH-LEVEL CLOUDS WERE SPREADING OVER CENTRAL
NORTH CAROLINA FROM THE SOUTH. THE LATEST WATER VAPOR IMAGES
INDICATED THE INCREASE OF THE MID-LEVEL MOISTURE WELL...STREAMING
NORTH AHEAD OF AN UPPER LOW OVER THE NORTHERN GULF. THE CANADIAN
CLOUD COVER MODEL...WHICH SEEMED TO HAVE A GOOD HANDLE ON THE CLOUD
COVER...SPREADS HIGH-LEVEL CLOUDS OVER CENTRAL NORTH CAROLINA FROM
THE SOUTHWEST DURING THE DAY...WITH NUMEROUS CLOUDS EXPECTED EVEN
OVER THE NORTHERN COASTAL PLAIN BY 18Z TO 20Z.
EARLY MORNING VISIBLE IMAGES SUGGESTS THE INITIAL SURGE OF HIGH
CLOUDS IS SOMEWHAT THIN...WHICH MAY PROVIDE FOR TIME FOR
TEMPERATURES TO RECOVER. AS SUN BECOMES MORE FILTERED OVER TIME WITH
LIKELY A GREATER DEGREE OF OPAQUE UPPER-LEVEL CLOUDS...THE EFFECT
SHOULD DAMPEN THE TEMPERATURE RISE. STILL...DID NOT LOWER MAXES TOO
MUCH...ONLY ABOUT A DEGREE OR SO...AS THERE MAY BE ENOUGH THIN SPOTS
TO GET WARMING SUFFICIENT FOR ABOUT 10 TO 15 DEGREES OF TEMPERATURE
INCREASE BEYOND THIS WRITING AT AN EARLY SUN TIME. RAP MODEL
SOUNDINGS SHOW MOISTENING ONLY ALOFT...WITH DRY AIR BELOW 500MB AND
A VERY CAPPED AIR MASS.
TONIGHT...MID-HIGH LEVEL CLOUDS WILL THICKEN IN RESPONSE TO THE
APPROACH OF THE NORTHERN GULF S/W THOUGH LIFT TO GENERATE ANY
SHOWERS APPEARS TO BE LACKING. WEAK (EMPHASIS ON WEAK) LOW LEVEL
ISENTROPIC LIFT MAY GENERATE A SHOWER OR SPRINKLES AROUND DAYBREAK
OVER THE FAR SOUTHERN PIEDMONT. THE INCREASING CLOUDINESS AND A
MODIFYING AIR MASS WILL YIELD MIN TEMPS A FEW DEGREES WARMER THAN
LOW TEMPS EXPECTED THIS MORNING. MIN TEMPS MID 60S NORTH TO THE
UPPER 60S SOUTH.
&&
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 333 AM SATURDAY...
HAVE TRENDED FORECAST THIS PERIOD A LITTLE WETTER...ESPECIALLY
SUNDAY NIGHT ACROSS THE PIEDMONT AND SANDHILLS.
ATMOSPHERE WILL CONTINUE TO MOISTEN AS NORTHERN GULF SYSTEM LIFTS
NEWD ACROSS GA AND INTO THE SOUTHERN APPALACHIANS LATE IN THE DAY.
THE APPROACH OF THIS SYSTEM WILL INDUCE A LOW LEVEL SELY
FLOW...RESULTING IN AN UPSLOPE COMPONENT TO THE LOW LEVEL FLOW OVER
THE SOUTHERN-WESTERN PIEDMONT. THE GFS SOLUTION IS A BIT MORE
AGGRESSIVE WITH THIS SCENARIO COMPARED TO THE NAM WHILE THE 00Z
ECMWF FAVORS THE GFS SOLUTION. INCREASING UPPER DIVERGENCE BY SUNDAY
AFTERNOON IN CONJUNCTION WITH A SLIGHTLY UNSTABLE AND INCREASINGLY
MOIST AIR MASS SHOULD SUPPORT THE DEVELOPMENT OF A FEW SHOWERS AND
AN ISOLATED STORM...MAINLY ACROSS PORTIONS OF THE SOUTHERN PIEDMONT
AND THE SANDHILLS. MAY SEE ADDITIONAL COVERAGE OVER THE
SANDHILLS/SOUTHERN COASTAL PLAIN DUE TO THE INLAND MOVING SEABREEZE.
THUS...WILL INCREASE POPS BIT FROM THE PREVIOUS FORECAST...UP TO 40
PERCENT OVER THE SOUTH AND WEST SECTIONS BY LATE IN THE DAY/SUNDAY
EVENING.
DUE TO EXPECTED EXTENSIVE CLOUDINESS...HAVE ADJUSTED MAX TEMPS DOWN
A BIT OVER THE WEST AND SW...WITH LITTLE CHANGE ELSEWHERE. IF CLOUDS
ARE LOWER/THICKER THAN EXPECTED OR SHOWER COVERAGE MORE EXTENSIVE BY
AFTERNOON...MAX TEMPS MAY END UP BEING 3-4 DEGREES COOLER THAN
FORECAST EVERYWHERE.
SUNDAY NIGHT...S/W LIFTS NEWD IMMEDIATELY WEST OF OUR REGION LATE IN
THE NIGHT...MAXIMIZING UPPER DIVERGENCE. IN THE 850-700MB LAYER WEAK
SPEED CONVERGENCE IN THE MOIST LAYER. THUS...SHOULD SEE A THREAT FOR
A FEW SHOWERS THROUGHOUT THE NIGHT...MAINLY ACROSS THE PIEDMONT. MIN
TEMPS MAINLY IN THE UPPER 60S TO NEAR 70.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 355 AM SATURDAY...
THE MODELS ARE IN BETTER AGREEMENT TODAY REGARDING THE
EJECTION/PROGRESSION OF A SHORTWAVE TROUGH --INITIALLY A CLOSED LOW
OVER THE CENTRAL GULF COAST THIS MORNING-- FROM THE CENTRAL
APPALACHIANS TO THE MIDDLE ATLANTIC COAST ON MON. MEANWHILE...AN
UPSTREAM KICKER SHORTWAVE TROUGH WILL AMPLIFY INTO THE SOUTHERN
PLAINS TO LOWER AND MID MS VALLEY AND RE-CARVE THE TROUGH
WESTWARD...AND CONSEQUENTLY ALLOW THE SUB-TROPICAL RIDGE TO BULGE
WESTWARD INTO THE SOUTHEAST US. A STRONGLY POSITIVELY-TILTED SHEAR
AXIS WILL SEPARATE THE SOUTHEASTERN RIDGE AND ANOTHER FORECAST TO
BUILD ACROSS THE OH VALLEY AND GREAT LAKES...AND THIS FEATURE WILL
INITIALLY DRAW TROPICAL MOISTURE ASSOCIATED WITH (AND IN ADVANCE OF)
ERIKA...NORTHWARD THROUGH THE CAROLINAS EARLY NEXT WEEK.
THEREAFTER...MOISTURE FROM (AND THE OVERALL INFLUENCE OF)
ERIKA...WILL BE DEPENDENT ON HOW ERIKA EVOLVES DURING THE NEXT
SEVERAL DAYS...WHICH IS A RELATIVELY LOW CONFIDENCE FORECAST.
THE ENVELOPE OF GUIDANCE SOLUTIONS HAS CONTINUED A WESTWARD TREND
WITH THE TRACK OF WHAT BECOMES OF ERIKA...WITH THE PREFERRED NHC
TRACK NOW THROUGH THE EASTERN GULF OF MEXICO/ALONG THE WEST COAST OF
FL EARLY NEXT WEEK...TO A POSITION NEAR THE FL PANHANDLE OR SOUTHERN
GA BY WED. CONSIDERABLE FORECAST UNCERTAINTY REMAINS WITH ERIKA...
HOWEVER...SINCE THE CIRCULATION MAY DISSIPATE ALTOGETHER DUE TO THE
INTERACTION WITH BOTH LAND AND A HOSTILE WIND SHEAR ENVIRONMENT
DURING THE NEXT 24-36 HOURS. OR IF IT SURVIVES... REGENERATION/
STRENGTHENING WILL BE POSSIBLE OVER THE WARM WATERS AND IN A
WEAKENING WIND SHEAR ENVIRONMENT OVER THE FL STRAITS AND EASTERN GOM.
REGARDLESS...IT STILL APPEARS THAT THE LOW LEVEL VORTICITY
CENTER...IN WHATEVER STATE IT MAY BE BY THE MIDDLE OF NEXT
WEEK...WILL LIKELY BE SUPPRESSED MOSTLY SOUTH AND/OR WEST OF CENTRAL
NC BY THE MERGING OF THE AFOREMENTIONED RIDGES ALOFT FROM THE GREAT
LAKES TO THE SE COAST. AS SUCH...OUR SENSIBLE WEATHER WILL LIKELY
INSTEAD BE INFLUENCED INDIRECTLY BY ASSOCIATED MOISTURE STREAMING
NNE ALONG THE AFOREMENTIONED SHEAR AXIS...WHICH WOULD RESULT IN BOTH
VARIABLY CLOUDY CONDITIONS AND SUPPORT FOR SLIGHTLY ABOVE CLIMO
PRECIPITATION CHANCES - HIGHEST SOUTH IN CLOSEST PROXIMITY TO THE
REMNANTS OF ERIKA. TEMPERATURES SHOULD BE CLOSE TO CLIMO - PERHAPS A
LITTLE BELOW /ABOVE FOR HIGHS/LOWS DEPENDING ON TIMING AND EXTENT OF
MOISTURE/CLOUD COVER.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
AS OF 640 AM SATURDAY...
THERE IS A HIGH PROBABILITY OF VFR CONDITIONS PERSISTING ACROSS
CENTRAL NC THROUGH EARLY SUNDAY. HIGH PRESSURE CENTERED OVER THE
NORTHERN MID ATLANTIC WILL EXTEND SOUTH INTO CENTRAL NC...CAUSING
THE VFR CONDITIONS. A DECK OF HIGH CLOUDS WILL PREVAIL LATER TODAY
AND TONIGHT WITH BASES ABOVE 10K FEET. SFC WINDS WILL BE GENERALLY
LIGHT AND VARIABLE THOUGH KFAY AND KRWI SHOULD SEE A PREDOMINATE
EAST-NE SFC WIND LATER THIS MORNING THROUGH EARLY AFTERNOON...
BETWEEN 7-10KTS.
WHILE VFR CONDITIONS WILL LIKELY CONTINUE INTO EARLY NEXT
WEEK...THERE WILL BE A THREAT FOR SCATTERED CONVECTION SUNDAY
THROUGH MONDAY AS AN UPPER DISTURBANCE LIFTS NWD ACROSS THE
CAROLINAS FROM THE DEEP SOUTH. MVFR CEILINGS/VISIBILITY COULD OCCUR
IN VICINITY OF THE CONVECTION.
THE AIR MASS WILL BECOME INCREASINGLY MOIST AND UNSTABLE TUESDAY AND
WEDNESDAY...SUGGESTING A BETTER CHANCE FOR PERIODS OF MVFR/IFR
CEILINGS DUE TO STRATUS IN THE OVERNIGHT-EARLY MORNING HOURS...AND
SCATTERED CONVECTION.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF/WSS
NEAR TERM...DJF/WSS
SHORT TERM...WSS
LONG TERM...26
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
950 PM CDT SUN AUG 30 2015
.UPDATE...
ISSUED AT 946 PM CDT SUN AUG 30 2015
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE...WITH A TIME
LAGGED ENSEMBLE OF THE 23-01 UTC HRRR ITERATIONS AND THE 00 UTC
NAM NEST STILL HANDLING WELL THE ONGOING POST-FRONTAL CONVECTION
ACROSS EASTERN MONTANA AND INTO SOUTHWEST NORTH DAKOTA.
THUS...WILL FOLLOW THEIR SOLUTIONS FOR POPS THE REMAINDER OF THE
NIGHT.
UPDATE ISSUED AT 627 PM CDT SUN AUG 30 2015
AS OF 2330 UTC...A COLD FRONT WAS PROPAGATING ACROSS THE HIGHWAY
83 CORRIDOR...AND WILL CONTINUE ITS EASTWARD PROGRESSION THROUGH
THE EVENING. THEREAFTER...POST-FRONTAL CONVECTION IS EXPECTED TO
ENTER SOUTHWEST NORTH DAKOTA AROUND 05 UTC AND SPREAD NORTHEAST
THROUGH THE NIGHT. THIS IS IN ASSOCIATION WITH MULTIPLE IMPULSES
EMBEDDED IN SOUTHWEST FLOW ALOFT AHEAD OF THE STRONGER NORTHERN
US ROCKIES SHORTWAVE. GIVEN GOOD HANDLING OF ONGOING CONVECTION
THROUGH 23 UTC...USED A BLEND THE 20-22 UTC HRRR TIME LAGGED
ENSEMBLE AND 18 UTC NAM NEST.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 345 PM CDT SUN AUG 30 2015
COLD FRONT ACROSS NORTHWEST NORTH DAKOTA SUNDAY AFTERNOON IS
NEARLY ALIGNED WITH THE FLOW ALOFT AND THUS IS MOVING SLOWLY
EAST. IT APPEARS SOME SMOKE IS POOLING ALONG THE FRONTAL BOUNDARY
AND IMPACTING NORTHWEST NORTH DAKOTA WITH WILLISTON AROUND 2 MILES
IN HAZE/SMOKE SO FAR THIS AFTERNOON. WILL ADD A PERIOD OF SMOKEY
WEATHER FOR NORTHWEST NORTH DAKOTA THROUGH THE MID EVENING.
OTHERWISE WILL NOT MENTION MORE SMOKE TONIGHT. SCATTERED SHOWERS
AND ISOLATED THUNDERSTORMS WILL FOLLOW THE FRONT AS IT PROGRESSES
SLOWLY ACROSS THE STATE TONIGHT. KEPT POPS ON THE LOW SIDE WITH
NOT MUCH MORE THAN 30 PERCENT POPS TONIGHT ENDING MONDAY MORNING.
COOLER MONDAY WITH HIGHS IN THE MID 70S TO LOWER 80S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 345 PM CDT SUN AUG 30 2015
CONTINUED WARM TEMPERATURES AND SLIGHT/PERIODIC THUNDERSTORM
CHANCES WILL HIGHLIGHT THE EXTENDED FORECAST PERIOD NEXT WEEK.
A SIGNIFICANT PATTERN CHANGE IS THEN DEPICTED FOR LATE NEXT
WEEKEND INTO THE EARLY PORTIONS OF THE FOLLOWING WORK WEEK.
ON TUESDAY...MAINTAINED A SLIGHT CHANCE OF MAINLY EVENING AND
OVERNIGHT THUNDERSTORMS FOR THE DEVILS LAKE BASIN AND JAMES RIVER
VALLEY WITH MODELS STILL SHOWING INCREASING INSTABILITY WITH
DAYTIME HEATING COUPLED WITH AN INCREASING LOW LEVEL JET ACROSS
THE EASTERN HALF OF THE STATE. CAPPING DURING THE DAY MAY HOLD
OFF ON CONVECTION UNTIL AFTER 00Z.
BEYOND TUESDAY...OUR SOUTHWEST UPPER FLOW WILL CONTINUE THROUGH THE
END OF THE EXTENDED PERIOD WITH TROUGHING ACROSS THE PACIFIC
NORTHWEST AND RIDGING OFF TO OUR EAST. A QUASI-STATIONARY SURFACE
TROUGH COMBINED WITH ANY EMBEDDED WAVES ALOFT WILL PROVIDE A FOCUS
FOR MAINLY ISOLATED DAILY SHOWER AND THUNDERSTORM ACTIVITY. BEST
CHANCES APPEAR TO BE TOWARDS THE END OF THE WORK WEEK AND INTO
NEXT WEEKEND WHEN A STRONG UPPER JET APPROACHES THE NORTHERN
PLAINS. TEMPERATURES WILL REMAIN NEAR TO SLIGHTLY ABOVE NORMAL
THROUGH THE WORK WEEK WITH 80S TO LOW 90S FOR HIGHS THEN COOLING A
BIT INTO THE 70S AND 80S BY NEXT WEEKEND.
BOTH THE 12Z GFS/ECMWF THEN BRING A STRONG COLD FRONT THROUGH THE
REGION LATE NEXT WEEKEND OR EARLY NEXT WEEK. BOTH MODELS INDICATE
THE POTENTIAL FOR A SIGNIFICANT COOL DOWN WITH 850MB TEMPERATURES
3-5C DEGREES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 946 PM CDT SUN AUG 30 2015
SCATTERED THUNDERSTORMS ARE EXPECTED TO ENTER SOUTHWEST NORTH
DAKOTA AROUND 3-4 UTC...AND SPREAD NORTHEAST THROUGH THE NIGHT. A
FEW POCKETS OF MVFR VISIBILITIES IN SMOKE ARE POSSIBLE ACROSS THE
AREA TONIGHT. SMOKE MAY BECOME MORE WIDESPREAD AND THICKER
THROUGHOUT THE DAY ON MONDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...WAA
LONG TERM...NH
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
646 PM CDT SUN AUG 30 2015
.UPDATE...
ISSUED AT 627 PM CDT SUN AUG 30 2015
AS OF 2330 UTC...A COLD FRONT WAS PROPAGATING ACROSS THE HIGHWAY
83 CORRIDOR...AND WILL CONTINUE ITS EASTWARD PROGRESSION THROUGH
THE EVENING. THEREAFTER...POST-FRONTAL CONVECTION IS EXPECTED TO
ENTER SOUTHWEST NORTH DAKOTA AROUND 05 UTC AND SPREAD NORTHEAST
THROUGH THE NIGHT. THIS IS IN ASSOCIATION WITH MULTIPLE IMPULSES
EMBEDDED IN SOUTHWEST FLOW ALOFT AHEAD OF THE STRONGER NORTHERN
US ROCKIES SHORTWAVE. GIVEN GOOD HANDLING OF ONGOING CONVECTION
THROUGH 23 UTC...USED A BLEND THE 20-22 UTC HRRR TIME LAGGED
ENSEMBLE AND 18 UTC NAM NEST.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 345 PM CDT SUN AUG 30 2015
COLD FRONT ACROSS NORTHWEST NORTH DAKOTA SUNDAY AFTERNOON IS
NEARLY ALIGNED WITH THE FLOW ALOFT AND THUS IS MOVING SLOWLY
EAST. IT APPEARS SOME SMOKE IS POOLING ALONG THE FRONTAL BOUNDARY
AND IMPACTING NORTHWEST NORTH DAKOTA WITH WILLISTON AROUND 2 MILES
IN HAZE/SMOKE SO FAR THIS AFTERNOON. WILL ADD A PERIOD OF SMOKEY
WEATHER FOR NORTHWEST NORTH DAKOTA THROUGH THE MID EVENING.
OTHERWISE WILL NOT MENTION MORE SMOKE TONIGHT. SCATTERED SHOWERS
AND ISOLATED THUNDERSTORMS WILL FOLLOW THE FRONT AS IT PROGRESSES
SLOWLY ACROSS THE STATE TONIGHT. KEPT POPS ON THE LOW SIDE WITH
NOT MUCH MORE THAN 30 PERCENT POPS TONIGHT ENDING MONDAY MORNING.
COOLER MONDAY WITH HIGHS IN THE MID 70S TO LOWER 80S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 345 PM CDT SUN AUG 30 2015
CONTINUED WARM TEMPERATURES AND SLIGHT/PERIODIC THUNDERSTORM
CHANCES WILL HIGHLIGHT THE EXTENDED FORECAST PERIOD NEXT WEEK.
A SIGNIFICANT PATTERN CHANGE IS THEN DEPICTED FOR LATE NEXT
WEEKEND INTO THE EARLY PORTIONS OF THE FOLLOWING WORK WEEK.
ON TUESDAY...MAINTAINED A SLIGHT CHANCE OF MAINLY EVENING AND
OVERNIGHT THUNDERSTORMS FOR THE DEVILS LAKE BASIN AND JAMES RIVER
VALLEY WITH MODELS STILL SHOWING INCREASING INSTABILITY WITH
DAYTIME HEATING COUPLED WITH AN INCREASING LOW LEVEL JET ACROSS
THE EASTERN HALF OF THE STATE. CAPPING DURING THE DAY MAY HOLD
OFF ON CONVECTION UNTIL AFTER 00Z.
BEYOND TUESDAY...OUR SOUTHWEST UPPER FLOW WILL CONTINUE THROUGH THE
END OF THE EXTENDED PERIOD WITH TROUGHING ACROSS THE PACIFIC
NORTHWEST AND RIDGING OFF TO OUR EAST. A QUASI-STATIONARY SURFACE
TROUGH COMBINED WITH ANY EMBEDDED WAVES ALOFT WILL PROVIDE A FOCUS
FOR MAINLY ISOLATED DAILY SHOWER AND THUNDERSTORM ACTIVITY. BEST
CHANCES APPEAR TO BE TOWARDS THE END OF THE WORK WEEK AND INTO
NEXT WEEKEND WHEN A STRONG UPPER JET APPROACHES THE NORTHERN
PLAINS. TEMPERATURES WILL REMAIN NEAR TO SLIGHTLY ABOVE NORMAL
THROUGH THE WORK WEEK WITH 80S TO LOW 90S FOR HIGHS THEN COOLING A
BIT INTO THE 70S AND 80S BY NEXT WEEKEND.
BOTH THE 12Z GFS/ECMWF THEN BRING A STRONG COLD FRONT THROUGH THE
REGION LATE NEXT WEEKEND OR EARLY NEXT WEEK. BOTH MODELS INDICATE
THE POTENTIAL FOR A SIGNIFICANT COOL DOWN WITH 850MB TEMPERATURES
3-5C DEGREES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 627 PM CDT SUN AUG 30 2015
A BRIEF PERIOD OF IFR VISIBILITY IN SMOKE WILL CONTINUE AT KMOT
THROUGH 02 UTC THIS EVENING. OTHERWISE...A COLD FRONT ACROSS
CENTRAL NORTH DAKOTA AS OF 23 UTC WILL CONTINUE TO MOVE EAST
THROUGH THE NIGHT. SCATTERED THUNDERSTORMS ARE EXPECTED TO ENTER
SOUTHWEST NORTH DAKOTA AROUND 5 UTC...AND SPREAD NORTHEAST THROUGH
THE NIGHT. VFR CONDITIONS EXPECTED OUTSIDE OF THUNDERSTORMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...WAA
LONG TERM...NH
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1237 AM CDT SAT AUG 29 2015
.UPDATE...
ISSUED AT 1237 AM CDT SAT AUG 29 2015
VISIBILITIES WERE AROUND 3-6 MILES IN SMOKE OVER PARTS OF WESTERN
AND CENTRAL NORTH DAKOTA. EXPECTING FOG FORMATION AS WELL OVER MUCH
OF CENTRAL NORTH DAKOTA...WITH RELATIVELY HUMID AIR WITH DEWPOINTS
IN THE 60S. FARTHER WEST DEWPOINTS WERE IN THE 40S AND 50S WITH THE
INFLUENCE OF THE DRIER WESTERN US RIDGE AIRMASS. EXPECT VISIBILITIES
REDUCED FOR THE EARLY MORNING HOURS UNTIL AFTER AROUND 8 TO 10 AM
CDT WHEN SOME SOUTHERLY/SOUTHWESTERLY WINDS BEGIN TO INCREASE.
OTHERWISE MADE SOME MINIMUM TEMPERATURE ADJUSTMENTS...WITH HETTINGER
ALREADY DIPPING TO 54 DEGREES. MAIN ELEMENTS OF THE FORECAST REMAIN
ON TRACK.
UPDATE ISSUED AT 845 PM CDT FRI AUG 28 2015
ADDED A MENTION OF FOG FOR TONIGHT INTO SATURDAY MORNING FOR
LOCATIONS GENERALLY ALONG AND EAST OF US HIGHWAY 83...WHERE MID
TO UPPER 60S F DEWPOINTS WERE OBSERVED AS OF 01 UTC. THE 23-00 UTC
RAP ITERATIONS HOLD THIS MOISTURE IN THROUGH THE NIGHT...SUPPORTED
BY THE HRRR VISIBILITY PRODUCT RAPIDLY DECREASING LATE TONIGHT
INTO SATURDAY MORNING FOR THE AFOREMENTIONED AREAS.
UPDATE ISSUED AT 633 PM CDT FRI AUG 28 2015
DID ADD AREAS OF SMOKE TO THE FORECAST FOR THE REMAINDER OF THE
EVENING INTO SATURDAY GIVEN SATELLITE AND SURFACE OBSERVATION
TRENDS THROUGH 23 UTC. OTHERWISE...THE FORECAST REMAINS ON TRACK.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM CDT FRI AUG 28 2015
MAIN CONCERN IN THE SHORT TERM WILL BE FIRE WEATHER POTENTIAL OVER
WESTERN NORTH DAKOTA FOR SATURDAY. AFTER A QUIET NIGHT TONIGHT A
VERY WARM AIRMASS WILL ALLOW TEMPERATURES TO RISE INTO THE 90S TO
NEAR 100 ACROSS WESTERN NORTH DAKOTA SATURDAY. MINIMUM RELATIVE
HUMIDITY COULD FALL AS LOW AS 15 PERCENT. A FIRE WEATHER WATCH HAS
BEEN ISSUED FOR WESTERN NORTH DAKOTA...WEST OF THE MISSOURI RIVER
UP TO LAKE SAKAKAWEA AND GENERALLY WEST OF HIGHWAY 83 NORTH OF
LAKE SAKAKAWEA.
OTHERWISE...A WEAK TROUGH OF LOW PRESSURE WAS THE FOCUS FOR A FEW
THUNDERSTORMS FRIDAY MORNING AND EARLY AFTERNOON ACROSS NORTHEAST
ND. AS THIS TROUGH SLIDES SOUTHEAST THIS AFTERNOON AND EVENING AN
ISOLATED THUNDERSTORM MAY YET BE POSSIBLE ACROSS THE JAMES RIVER
VALLEY INTO THIS EVENING. OTHERWISE WILL KEEP A MENTION OF SMOKE
IN TONIGHT MOST OF WEST AND CENTRAL NORTH DAKOTA. THE SMOKE HAS
BEEN MAINLY ALOFT BUT SKIES ARE QUITE COVERED WITH IT AND THERE
CONTINUES TO BE A SCENT OF IT AT THE SURFACE.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM CDT FRI AUG 28 2015
WARM TEMPERATURES AND PERIODIC THUNDERSTORM CHANCES WILL HIGHLIGHT
THE EXTENDED FORECAST PERIOD NEXT WEEK.
WESTERN CONUS UPPER LEVEL RIDGE WILL AMPLIFY INTO THE CENTRAL U.S
OVER THE UPCOMING WEEKEND...THEN TRANSLATE TO THE EASTERN CONUS NEXT
WEEK PUTTING SOUTHWEST FLOW ALOFT INTO THE NORTHERN PLAINS THROUGH
THE WORK WEEK. THE UPPER RIDGE THIS WEEKEND WILL BRING WELL ABOVE
NORMAL TEMPERATURES AND LIMITED PRECIPITATION CHANCES TO WESTERN
AND CENTRAL NORTH DAKOTA THROUGH SUNDAY DAYTIME.
ON SUNDAY WE ARE EXPECTING SLIGHTLY COOLER TEMPERATURES IN THE
NORTHWEST. THE THERMAL RIDGE SHIFTS INTO CENTRAL NORTH
DAKOTA...THUS MINOT AND BISMARCK COULD SEE TEMPERATURES
APPROACHING RECORDS ONCE AGAIN FOR SUNDAY...BUT MUCH WILL DEPEND
ON THE TIMING OF AN APPROACHING COLD FRONT.
ISOLATED THUNDERSTORMS WILL ENTER THE FORECAST SUNDAY NIGHT WITH
ENERGY ALOFT AND THE AFOREMENTIONED COLD FRONT/SFC BOUNDARY
MOVING SLOWLY SOUTH AND EAST THROUGH NORTH DAKOTA...COOLING
TEMPERATURES BACK DOWN INTO THE 80S FOR MONDAY.
BROAD SOUTHWEST UPPER LEVEL FLOW WILL THEN PERSIST THROUGH NEXT
WEEK. NO MAJOR SYSTEMS DEPICTED...BUT WE CAN EXPECT DAILY ISOLATED
TO SCATTERED THUNDERSTORM CHANCES WITH ANY EMBEDDED SHORTWAVE
WHICH TRAVELS THROUGH THE FLOW ALOFT COUPLED WITH ANY ASSOCIATED
BOUNDARY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1237 AM CDT SAT AUG 29 2015
MVFR VISIBILITY IN SMOKE FROM NORTHWEST U.S. FIRES ARE POSSIBLE
AT KDIK/KISN/KBIS/KMOT THIS MORNING. SMOKE MAY BE DENSE ENOUGH TO
DROP VISIBILITY TO IFR AT KDIK AND KISN TONIGHT. PATCHY FOG IS
POSSIBLE IN THE KJMS/KBIS VICINITY THIS MORNING. ADDED MENTION OF
SCT-BKN CIGS AT 3000-5000 FEET AS SENSORS DETECTING A CIG WITH SMOKE
PARTICLES. AFTER 16Z SOUTH TO SOUTHWEST WINDS SHOULD INCREASE AND
DISSIPATE FOG AND SURFACE SMOKE. VFR CONDITIONS EXPECTED AFTER VSBY
REDUCTIONS END BY AROUND 16Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM 11 AM CDT /10 AM MDT/ THIS MORNING
THROUGH THIS EVENING FOR NDZ001-002-009>011-017>021-031>034-
040>045.
&&
$$
UPDATE...JV
SHORT TERM...WAA
LONG TERM...NH
AVIATION...JV
AREA FORECAST DISCUSSION...UPDATED
NWS NORMAN OK
927 PM CDT SUN AUG 30 2015
.UPDATE...
RAIN HAS ENDED ACROSS THE FA. THE REST OF THE NIGHT IS EXPECTED
TO REMAIN DRY BUT IT IS NOT COMPLETELY OUT OF THE QUESTION THAT A
FEW MORE ISOLATED SHOWERS/STORMS MAY DEVELOP IN SE PARTS OF THE
FA. HOWEVER... WILL KEEP POP/WX FORECAST DRY FOR NOW. CLOUDS IN
THE SE ARE EXPECTED TO GRADUALLY DECREASE OVERNIGHT. SOME PATCHY
FOG IS STILL POSSIBLE TOWARDS MORNING IN NORTHERN PARTS OF THE FA
SO WILL KEEP MENTION IN THE FORECAST. UPDATES OUT SOON.
&&
.PREV DISCUSSION... /ISSUED 610 PM CDT SUN AUG 30 2015/
AVIATION...
MAINLY VFR CONDITIONS EXPECTED THROUGH THE FORECAST
PERIOD. THERE IS AN OUTSIDE CHANCE FOR SOME PATCHY FOG ACROSS
NORTHERN OKLAHOMA OVERNIGHT... BUT CHANCES REMAIN TOO LOW TO MENTION
AT THIS POINT. WINDS WILL BECOME SOUTHERLY ON MONDAY WITH SOME GUSTS
APPROACHING 20KTS ACROSS THE WEST BY AFTN.
30
PREV DISCUSSION... /ISSUED 220 PM CDT SUN AUG 30 2015/
DISCUSSION...
MAINLY DRY WEATHER AND NEAR OR SLIGHTLY ABOVE AVERAGE TEMPERATURES
ARE EXPECTED DURING THE NEXT SEVEN DAYS.
THROUGH 10 PM THIS EVENING...A FEW THUNDERSTORMS MAY FORM NEAR A
WEAK SURFACE FRONT OVER SOUTHERN OKLAHOMA...NEAR WAURIKA TO
COALGATE. CAPPING IS RATHER STRONG...HOWEVER A MID LEVEL
WEAKNESS CENTERED OVER EASTERN OKLAHOMA MAY BE ENOUGH FOR TO
ALLOW FOR ISOLATED DEVELOPMENT. THUS...WENT WITH A 20 PERCENT
CHANCE IN THESE LOCATIONS. IF STORMS FORM...THEY WOULD BE SLOW
MOVERS...PRODUCE LOCALIZED DOWNPOURS...AND GUSTY WINDS PERHAPS UP
TO 50 TO 60 MPH. ANY CONVECTION WOULD DIMINISH WITH THE LOSS OF
DAYTIME HEATING.
AFTER 10 PM THIS EVENING INTO MONDAY MORNING...PATCHY FOG MAY FORM
AGAIN ACROSS MAINLY NORTHERN OKLAHOMA. LATEST HRRR RUNS HAVE BEEN
CONSISTENT WITH DEPICTING LOW CLOUDS AND FOG OVER NEAR ALVA...
ENID...AND CHEROKEE. THIS SEEMS REASONABLE AS HIGHER SURFACE
DEWPOINTS ARE FORECAST TO MOVE INTO THESE LOCATIONS LATE TONIGHT.
THUS...ADDED MENTION OF PATCHY FOG. DOUBT FOG WILL BE TOO DENSE
OR WIDESPREAD SINCE NO RAIN WILL OCCUR IN THESE LOCATIONS TODAY.
MONDAY WILL BE MOSTLY SUNNY AND HOTTER WITH INCREASING SOUTH
SURFACE WINDS. CANNOT COMPLETELY RULE OUT A STRAY AFTERNOON OR
EVENING STORM IN SOUTHEAST OF A WAURIKA TO ADA LINE WHERE MID
LEVEL TEMPERATURES WILL BE A BIT COOLER AND CAPPING IS A BIT
WEAKER...BUT WILL NOT MENTION DUE TO LOW CONFIDENCE OF OCCURRENCE.
MONDAY NIGHT THROUGH NEXT SUNDAY...SEASONABLY HOT AND MAINLY DRY
WEATHER WILL CONTINUE WITH A WEAK MID/UPPER RIDGE OVERHEAD. LOW
STORM CHANCES MAY RETURN TO MAINLY NORTHWESTERN OKLAHOMA BY THE
WEEKEND...BUT CONFIDENCE IS LOW.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 66 93 70 92 / 0 0 0 0
HOBART OK 65 97 71 96 / 0 0 0 0
WICHITA FALLS TX 69 97 72 97 / 0 0 0 0
GAGE OK 62 96 69 95 / 0 0 0 0
PONCA CITY OK 66 93 70 93 / 0 0 0 0
DURANT OK 71 95 71 94 / 20 10 0 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
25/30
AREA FORECAST DISCUSSION
NWS NORMAN OK
610 PM CDT SUN AUG 30 2015
.AVIATION...
MAINLY VFR CONDITIONS EXPECTED THROUGH THE FORECAST
PERIOD. THERE IS AN OUTSIDE CHANCE FOR SOME PATCHY FOG ACROSS
NORTHERN OKLAHOMA OVERNIGHT... BUT CHANCES REMAIN TOO LOW TO MENTION
AT THIS POINT. WINDS WILL BECOME SOUTHERLY ON MONDAY WITH SOME GUSTS
APPROACHING 20KTS ACROSS THE WEST BY AFTN.
30
&&
.PREV DISCUSSION... /ISSUED 220 PM CDT SUN AUG 30 2015/
.DISCUSSION...
MAINLY DRY WEATHER AND NEAR OR SLIGHTLY ABOVE AVERAGE TEMPERATURES
ARE EXPECTED DURING THE NEXT SEVEN DAYS.
THROUGH 10 PM THIS EVENING...A FEW THUNDERSTORMS MAY FORM NEAR A
WEAK SURFACE FRONT OVER SOUTHERN OKLAHOMA...NEAR WAURIKA TO
COALGATE. CAPPING IS RATHER STRONG...HOWEVER A MID LEVEL
WEAKNESS CENTERED OVER EASTERN OKLAHOMA MAY BE ENOUGH FOR TO
ALLOW FOR ISOLATED DEVELOPMENT. THUS...WENT WITH A 20 PERCENT
CHANCE IN THESE LOCATIONS. IF STORMS FORM...THEY WOULD BE SLOW
MOVERS...PRODUCE LOCALIZED DOWNPOURS...AND GUSTY WINDS PERHAPS UP
TO 50 TO 60 MPH. ANY CONVECTION WOULD DIMINISH WITH THE LOSS OF
DAYTIME HEATING.
AFTER 10 PM THIS EVENING INTO MONDAY MORNING...PATCHY FOG MAY FORM
AGAIN ACROSS MAINLY NORTHERN OKLAHOMA. LATEST HRRR RUNS HAVE BEEN
CONSISTENT WITH DEPICTING LOW CLOUDS AND FOG OVER NEAR ALVA...
ENID...AND CHEROKEE. THIS SEEMS REASONABLE AS HIGHER SURFACE
DEWPOINTS ARE FORECAST TO MOVE INTO THESE LOCATIONS LATE TONIGHT.
THUS...ADDED MENTION OF PATCHY FOG. DOUBT FOG WILL BE TOO DENSE
OR WIDESPREAD SINCE NO RAIN WILL OCCUR IN THESE LOCATIONS TODAY.
MONDAY WILL BE MOSTLY SUNNY AND HOTTER WITH INCREASING SOUTH
SURFACE WINDS. CANNOT COMPLETELY RULE OUT A STRAY AFTERNOON OR
EVENING STORM IN SOUTHEAST OF A WAURIKA TO ADA LINE WHERE MID
LEVEL TEMPERATURES WILL BE A BIT COOLER AND CAPPING IS A BIT
WEAKER...BUT WILL NOT MENTION DUE TO LOW CONFIDENCE OF OCCURRENCE.
MONDAY NIGHT THROUGH NEXT SUNDAY...SEASONABLY HOT AND MAINLY DRY
WEATHER WILL CONTINUE WITH A WEAK MID/UPPER RIDGE OVERHEAD. LOW
STORM CHANCES MAY RETURN TO MAINLY NORTHWESTERN OKLAHOMA BY THE
WEEKEND...BUT CONFIDENCE IS LOW.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 66 93 70 92 / 0 0 0 0
HOBART OK 65 97 71 96 / 0 0 0 0
WICHITA FALLS TX 69 97 72 97 / 0 0 0 0
GAGE OK 62 96 69 95 / 0 0 0 0
PONCA CITY OK 66 93 70 93 / 0 0 0 0
DURANT OK 71 95 71 94 / 20 10 0 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
26/17
AREA FORECAST DISCUSSION...UPDATED
NWS PENDLETON OR
506 AM PDT SAT AUG 29 2015
UPDATED AVIATION DISCUSSION
.SHORT TERM...TODAY THROUGH MONDAY...POTENT UPPER LEVEL TROUGH OFF
THE OREGON COAST WILL LIFT NEWD INTO NW WASHINGTON AND DEAMPLIFY AS
IT MOVES INTO BRITISH COLUMBIA TODAY AND TONIGHT. THE MAIN IMPACT
FROM THIS SYSTEM WILL BE SOME RAIN ALONG THE CASCADES AND GUSTY SW
WINDS FROM MID MORNING UNTIL LATE THIS AFTERNOON. WIND ADVISORIES
ARE IN EFFECT FOR MUCH OF THE LOWER ELEVATIONS. WITH LITTLE RAIN
EXPECTED EAST OF THE CASCADES EXPECT SOME BLOWING DUST AS WELL.
BLOWING DUST ADVISORIES ARE IN EFFECT FOR THE BLUE MOUNTAIN
FOOTHILLS...YAKIMA VALLEY AND COLUMBIA BASIN. LOOKING AT THE PAST
FEW RUNS OF THE HRRR IT APPEARS THAT THE STRONGEST WIND TODAY WILL
BE OVER THE YAKIMA VALLEY AND SIMCOE HIGHLANDS WITH GUST POTENTIAL
REACHING 50 TO 55 MPH LATE THIS MORNING INTO EARLY THIS AFTERNOON.
THIS MAKES SENSE BECAUSE THIS AREA IS CLOSER TO THE TRACK OF THE
UPPER TROUGH. WINDS WILL DECREASE QUICKLY BY EARLY EVENING. AS A
SECOND UPPER TROUGH APPROACHES LATER TONIGHT RAIN IS EXPECTED TO
SPREAD EAST OF THE CASCADES. THIS RAIN WILL MOVE ACROSS THE ENTIRE
FORECAST AREA ON SUNDAY. BUMPED UP POPS QUITE A BIT FOR SUNDAY TO
REFLECT THE MODELS WETTER TRENDING...AND POPS MAY NEED TO BE RAISED
FURTHER. THERE IS A CHANCE FOR QUARTER INCH AMOUNTS WITH THIS SYSTEM
OVER A WIDE AREA WHICH WOULD REALLY HELP WITH THE ONGOING FIRES. BY
MONDAY THE TROUGH WILL HAVE MOVED EAST OF THE REGION WITH GENERALLY
DRY CONDITIONS AND COOL TEMPERATURES. 78
.LONG TERM...MONDAY NIGHT THROUGH SATURDAY..THE AREA WILL BE UNDER
THE INFLUENCE OF AN UPPER LEVEL TROUGH THROUGH THE LONG TERM PERIOD
AND UNSETTLED WEATHER IS EXPECTED. ON MONDAY NIGHT THE TROUGH WILL
BE BROAD AND SHALLOW WITH A WESTERLY FLOW OVER THE AREA. AN UPPER
LOW WILL BE OFF THE NORTHERN BRITISH COLUMBIA COAST AND WILL SINK
SOUTH, ENDING UP NEAR NORTHERN VANCOUVER ISLAND BY TUESDAY
AFTERNOON. RAIN SHOWERS WILL STRUGGLE TO GET VERY FAR PAST THE
CASCADE CREST THOUGH BY TUESDAY AFTERNOON, THERE SHOULD BE A FEW
LIGHT SHOWERS AS FAR EAST AS YAKIMA AND ELLENSBURG. THE REST OF THE
AREA WILL REMAIN DRY. WINDS WILL BECOME BREEZY TUESDAY AFTERNOON.
THE UPPER LOW WILL DEEPEN THE TROUGH AND TURN THE FLOW OVER OUR AREA
MORE SOUTHWESTERLY. A FRONT WILL MOVE THROUGH THE AREA TUESDAY NIGHT
AND WEDNESDAY BRINGING A CHANCE OF LIGHT RAIN TO THE ENTIRE AREA.
ANOTHER IMPULSE WILL MOVE THROUGH THE TROUGH ON THURSDAY AND BRING A
CHANCE OF RAIN AND A SLIGHT CHANCE OF THUNDERSTORMS TO THE MOUNTAINS
WITH A SLIGHT CHANCE OF RAIN IN CENTRAL OREGON AND THE BLUE MOUNTAIN
FOOTHILLS. THE GFS SHOWS THE IMPULSE CARVING THE TROUGH FURTHER
SOUTH ON FRIDAY WITH A SLIGHT CHANCE OF THUNDERSTORMS IN THE EASTERN
MOUNTAINS. THE ECMWF IS LESS VIGOROUS WITH THIS IMPULSE AND DOES NOT
SHOW ANY PRECIPITATION BUT DOES DEEPEN THE TROUGH SOMEWHAT. HAVE
LEANED TOWARDS THE GFS AND PUT A SLIGHT CHANCE OF THUNDERSTORMS IN
THE EASTERN MOUNTAINS. ON SATURDAY, BOTH MODELS SHOW THE TROUGH
STARTING TO MOVE EASTWARD WITH A SLIGHT CHANCE OF THUNDERSTORMS
MAINLY IN WALLOWA COUNTY AND THE HIGHER TERRAIN IN THE REST OF THE
EASTERN MOUNTAINS. TUESDAY WILL SEE TEMPERATURES IN THE 70S AND
LOWER 80S. WEDNESDAY AND THURSDAY WILL BE COOLER WITH HIGHS IN THE
MID 60S TO MID 70S. FRIDAY AND SATURDAY WILL SEE TEMPERATURES BACK
IN THE MID 70S TO LOWER 80S WITH MID 60S TO MID 70S IN THE
MOUNTAINS. PERRY
&&
.AVIATION...12Z TAFS...VFR CONDITIONS WILL CONTINUE FOR THE NEXT 24
HOURS HOWEVER A FRONTAL PASSAGE EARLY TO MIDDAY SATURDAY WILL CAUSE
MVFR AND PERHAPS IFR VISIBILITIES DUE TO BLOWING DUST AT KPSC, KALW,
KPDT AND KYKM. WINDS WILL INCREASE RAPIDLY IN THE NEXT FEW HOURS AND
WEST TO SOUTHWEST WINDS OF 20 TO 30 KTS WITH GUSTS TO 40 KTS ARE
EXPECTED FROM 17Z TO 01Z BEFORE WINDING DOWN TO BELOW 15 KTS BY 04Z.
KDLS IS EXPECTED TO HAVE WINDS OF 10 TO 20 KTS WITH GUSTS TO 30 KTS
DUE TO THE EAST/WEST ORIENTATION OF THE COLUMBIA GORGE BEING
SOMEWHAT SHELTERED FROM THE SOUTHWEST WINDS. CEILINGS WILL BE
GENERALLY SCATTERED TO BROKEN ABOVE 5000 FEET AGL. RAIN SHOWERS WILL
BE CONFINED TODAY TO IN AND NEAR THE CASCADES WITH KDLS HAVING -SHRA
THROUGH 20Z AND KRDM AND KBDN HAVING VCSH THROUGH 19Z. ANOTHER
DISTURBANCE WILL BRING -SHRA TO KDLS AND KYKM AFTER 08Z. PERRY
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 81 54 72 50 / 10 10 50 10
ALW 83 61 73 54 / 10 10 60 10
PSC 83 58 76 56 / 10 10 60 10
YKM 74 53 70 48 / 20 50 40 10
HRI 85 57 74 53 / 10 10 50 10
ELN 74 53 72 50 / 30 50 50 10
RDM 77 48 67 39 / 20 10 50 10
LGD 83 47 69 46 / 20 10 50 10
GCD 82 46 71 36 / 10 10 40 10
DLS 80 61 75 56 / 30 70 70 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WIND ADVISORY FROM 5 AM EARLY THIS MORNING TO 6 PM PDT THIS
EVENING FOR ORZ510-511.
RED FLAG WARNING FROM 7 AM THIS MORNING TO 7 PM PDT THIS EVENING
FOR ORZ640>645.
BLOWING DUST ADVISORY FROM 9 AM THIS MORNING TO 6 PM PDT THIS
EVENING FOR ORZ044-507-508.
WIND ADVISORY FROM 9 AM THIS MORNING TO 6 PM PDT THIS EVENING
FOR ORZ044-507-508.
WA...RED FLAG WARNING FROM 7 AM THIS MORNING TO 7 PM PDT THIS EVENING
FOR WAZ641-643-645-675.
BLOWING DUST ADVISORY FROM 9 AM THIS MORNING TO 6 PM PDT THIS
EVENING FOR WAZ027>029.
WIND ADVISORY FROM 9 AM THIS MORNING TO 6 PM PDT THIS EVENING
FOR WAZ027>029-521.
&&
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
78/83/83
AREA FORECAST DISCUSSION
NWS PORTLAND OR
308 AM PDT SAT AUG 29 2015
.SYNOPSIS...AN USUALLY EARLY AND STRONG LOW PRESSURE WILL PRODUCE
WIDESPREAD RAIN AND STRONG WINDS ACROSS NORTHWEST OREGON AND
SOUTHWEST WASHINGTON SATURDAY MORNING. A FEW THUNDERSTORMS EMBEDDED
IN THE RAIN MAY ENHANCE THE WIND THREAT SATURDAY MORNING. A SECOND
FRONT PUSHING INTO THE REGION FROM THE NORTHWEST SATURDAY NIGHT WILL
PRODUCE ANOTHER ROUND OF RAIN. ADDITIONAL SHOWERS WILL FOLLOW ON
SUNDAY. EXPECT COOL WEATHER AND ADDITIONAL ROUNDS OF SHOWERS FOR MUCH
OF THE UPCOMING WORK WEEK.
&&
.SHORT TERM...A FEW PREFRONTAL SHOWERS REMAIN OVER THE NORTH VALLEY
THIS MORNING WITH THE FRONTAL RAIN BAND MOVING ONSHORE. RADAR ALREADY
SHOWING SOME HIGHER REFLECTIVITY ACTIVITY OVER THE COAST RANGE AND
EVEN A FEW LIGHTNING STRIKES. ALTHOUGH THE RAINBAND IS NARROW...ITS
CURRENTLY MOVING MUCH MORE NORTH THAN EAST SO IT WILL BE SLOW TO
WORK ITS WAY INLAND AND MAY DROP 0.10 TO 0.20 INCHES OF RAIN PER
HOUR WITH MORE IN EMBEDDED STRONGER SHOWERS OR THUNDERSTORMS. THERE
DOES NOT APPEAR TO BE ANY RAIN IMMEDIATELY FOLLOWING THIS FRONTAL
BAND...SO THERE WILL BE A DEFINITE BREAK IN RAIN FROM THE TIME THE
BAND MOVES THROUGH TO WHEN ANY SHOWERS BEGIN TO POP UP THIS
AFTERNOON WITH DAYTIME HEATING. HAVE DRIED THE FORECAST OUT QUITE A
BIT 18Z TODAY TO 00Z SUNDAY BUT THE RAIN MAY HAVE MOVED THROUGH
EARLIER THAN EVEN THAT.
THE PARENT LOW CONTINUES TO STRENGTHEN AND IS CURRENTLY CENTERED
ABOUT 200 MILES WEST OF NORTH BEND ACCORDING TO LATEST IR SATELLITE
IMAGERY. BASED ON COMPARISON OF BUOY OBS AND 06Z NAM AND GFS
FORECASTS...LOOKS LIKE THE LOW IS AROUND 989 MB RIGHT NOW...OR
SLIGHTLY STRONGER THAN THE NAM AND GFS HAVE. THE 08Z HRRR SHOWS A
STRONGER LOW CURRENTLY AND FORECASTS THE PRESSURE DROPPING TO 985 MB
AT ITS CLOSEST APPROACH TO THE OREGON COAST...ABOUT 100 MILES
OFFSHORE. THIS WOULD BE 4 MB STRONGER THAN THE NAM AND GFS CURRENTLY
SHOW BUT WITH A SIMILAR TRACK AND SEEMS FAIRLY REALISTIC. HRRR ALSO
SHOWS RATHER IMPRESSIVE PRESSURE RISES BEHIND THE LOW LATE THIS
MORNING WITH 6+ MB IN 3 HOURS OVER THE EXTREME NW OREGON AND SW
WASHINGTON AREAS...MOSTLY CENTERED AROUND CLATSOP AND PACIFIC
COUNTIES. ALSO SEEING HIGH PRESSURE RISES JUST OFFSHORE THROUGH THE
CENTRAL OREGON COAST WHICH SHOULD TRANSLATE TO HIGH
WINDS...ESPECIALLY FOR THE BEACHES AND HEADLANDS. WILL KEEP HIGH WIND
WARNINGS IN PLACE AS IS. PRESSURE RISES AND PRESSURE GRADIENT THROUGH
THE VALLEY ARE LESS IMPRESSIVE WITH THE NORTH-SOUTH GRADIENT PEAKING
ONLY AT ABOUT 4 TO 5 MB BUT CONDITIONS WILL BE NOTICEABLY WINDY
NONETHELESS. 850 MB WINDS IN THE VALLEY ARE FORECAST TO BE 40 TO 50
KT WHEN THIS MORNING`S RAIN COMES THROUGH...SO ANY CONVECTION COULD
MIX DOWN SOME GOOD GUSTS. WILL LEAVE WIND ADVISORY AS IS SINCE THIS
IS AN ANOMALOUSLY STRONG WIND EVENT FOR LATE AUGUST...EVEN THOUGH
TECHNICAL CRITERIA MAY NOT BE MET.
MODELS HAVE TRENDED WETTER WITH A SECOND FRONT DROPPING SOUTHEASTWARD
OUT OF THE GULF OF ALASKA THAT WILL PUSH A HEALTHY DOSE OF RAIN
ACROSS THE AREA SATURDAY NIGHT. DECENT ONSHORE FLOW AND INSTABILITY
SHOULD LEAD TO MORE SHOWERS AND POSSIBLY A WET THUNDERSTORM OR TWO
SUNDAY.
BELOW AVERAGE TEMPERATURES AND ADDITIONAL ROUNDS OF WET WEATHER
APPEAR LIKELY NEXT WEEK. BOWEN
.LONG TERM (PREVIOUS DISCUSSION)...MONDAY NIGHT THROUGH FRIDAY. THE
FALL-LIKE WEATHER PATTERN WILL CONTINUE NEXT WEEK WITH PRIMARILY
COOLER THAN NORMAL TEMPERATURES...CLOUDY CONDITIONS...AND CHANCES FOR
ADDITIONAL RAIN. A TROUGH WILL REMAIN NEAR THE PACIFIC NORTHWEST
COAST THROUGH MOST OF THE PERIOD WITH SOME RAIN AT TIMES...ESPECIALLY
DURING THE EARLY AND MIDDLE PARTS OF NEXT WEEK. LITTLE CHANGE MADE TO
THE CURRENT FORECAST. TOLLESON
&&
.AVIATION...MOIST SW FLOW ALOFT OVER REGION...WITH RAIN INCREASING
THIS AM. WILL SEE FRONT PUSH N ACROSS THE REGION LATER THIS AM...
WITH INCREASING S WINDS. STRONGEST WINDS WILL BE ON COAST AND
OVER COAST RANGE...WITH S WIND GUSTS OF 40 TO 55 KT FOR THOSE
AREAS AND LESSER WINDS FURTHER INLAND. AT 2 AM...GENERALLY VFR
CONDITIONS. BUT WILL SEE INCREASING MVFR ALONG THE COAST BY 12Z.
RAIN WILL END BY 18Z FOR MOST AREAS...WITH CIGS BREAKING UP A BIT
AS MORE UNSTABLE AIR MASS WITH SHOWERS MOVES INTO REGION FOR THE
AFTERNOON. WOULD NOT BE SURPRISED TO SEE TRANSITION BACK TO VFR AT
TIMES AFTER 20Z. CIGS WILL LOWER BACK TO MVFR TONIGHT AS ANOTHER
FRONT AND MORE RAIN PUSHES INTO THE REGION.
KPDX AND APPROACHES...VFR...WITH RAIN UNTIL 18Z...THEN LIKELY TO
SEE A MIXTURE OF VFR WITH OCCASIONAL MVFR AS MORE SHOWERY PATTERN
PUSHES INTO REGION. WILL HAVE S WINDS GUSTING 25 TO 35 KT BETWEEN
17Z AND 23Z. WINDS EASE AFTER 00Z...BUT WILL HAVE INCREASING MVFR
AS RAIN INCREASES LATER SAT NIGHT. ROCKEY.
&&
.MARINE...MODELS CONTINUE TO BE WELL INITIALIZED WITH THE STRONG
LOW PRES NOW SITTING ABOUT 250 MILES SOUTHWEST OF NEWPORT THIS AM.
THIS LOW WILL LIFT NE ACROSS THE OREGON COASTAL WATERS AND INTO
NW WASHINGTON TODAY. BUT APPEARS THE ACTUAL LOW IS STRONGER THAN
THE MODELS INDICATE. THE LOW WILL GRADUALLY WEAKEN TODAY AS IT
MOVES NE...STRONGEST WINDS LOOK TO REMAIN S OF THE COLUMBIA RIVER.
SO...HAVE ISSUED STORM WARNING FOR COASTAL WATERS S OF THE
COLUMBIA RIVER WHERE THERE IS MODERATE TO HIGH POTENTIAL FOR 50 KT
GUSTS. REST OF THE REGION WILL REMAIN UNDER A GALE WARNING.
SEAS WILL BE BUILDING AS WINDS INCREASE. STILL LOOKS GOOD FOR SEAS
TO BE RUNNING AT 13 TO 17 FT BY MID TO LATE THIS AM. SEAS HOLD IN
THAT RANGE THROUGH THE DAY...BUT DROP BACK THIS EVENING.
WINDS WILL EASE LATER THIS AFTERNOON...LIKELY BELOW 25 KT BY 8 PM.
SEAS WILL ALSO SUBSIDE AS WINDS EASE...PROBABLY AROUND 8 TO 10 FT
LATER TONIGHT INTO SUNDAY.
UNSETTLED WEATHER CONTINUES INTO NEXT WEEK WITH SEAS STAYING 6 TO
9 FT THROUGH AT LEAST MIDWEEK. ROCKEY.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WIND ADVISORY FROM 8 AM THIS MORNING TO 3 PM PDT THIS AFTERNOON
FOR GREATER PORTLAND METRO AREA-LOWER COLUMBIA.
HIGH WIND WARNING UNTIL 1 PM PDT THIS AFTERNOON FOR CENTRAL
OREGON COAST.
WIND ADVISORY UNTIL NOON PDT TODAY FOR CENTRAL WILLAMETTE
VALLEY-SOUTH WILLAMETTE VALLEY.
HIGH WIND WARNING FROM 6 AM THIS MORNING TO 2 PM PDT THIS
AFTERNOON FOR COAST RANGE OF NORTHWEST OREGON-NORTH OREGON
COAST.
HIGH WIND WARNING FROM 5 AM EARLY THIS MORNING TO NOON PDT TODAY
FOR CENTRAL COAST RANGE OF WESTERN OREGON.
WA...WIND ADVISORY FROM 8 AM THIS MORNING TO 3 PM PDT THIS AFTERNOON
FOR GREATER VANCOUVER AREA-I-5 CORRIDOR IN COWLITZ COUNTY.
HIGH WIND WARNING FROM 8 AM THIS MORNING TO 3 PM PDT THIS
AFTERNOON FOR WILLAPA HILLS.
HIGH WIND WARNING FROM 8 AM THIS MORNING TO 2 PM PDT THIS
AFTERNOON FOR SOUTH WASHINGTON COAST.
PZ...STORM WARNING FROM 6 AM TO NOON TODAY ON ALL COASTAL WATERS
SOUTH OF THE COLUMBIA RIVER.
GALE WARNING UNTIL 8 PM TODAY ON ALL COASTAL WATERS THROUGH
8 PM TODAY.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR CONDITIONS
TODAY AND THIS EVENING.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS PENDLETON OR
300 AM PDT SAT AUG 29 2015
.SHORT TERM...TODAY THROUGH MONDAY...POTENT UPPER LEVEL TROUGH OFF
THE OREGON COAST WILL LIFT NEWD INTO NW WASHINGTON AND DEAMPLIFY AS
IT MOVES INTO BRITISH COLUMBIA TODAY AND TONIGHT. THE MAIN IMPACT
FROM THIS SYSTEM WILL BE SOME RAIN ALONG THE CASCADES AND GUSTY SW
WINDS FROM MID MORNING UNTIL LATE THIS AFTERNOON. WIND ADVISORIES
ARE IN EFFECT FOR MUCH OF THE LOWER ELEVATIONS. WITH LITTLE RAIN
EXPECTED EAST OF THE CASCADES EXPECT SOME BLOWING DUST AS WELL.
BLOWING DUST ADVISORIES ARE IN EFFECT FOR THE BLUE MOUNTAIN
FOOTHILLS...YAKIMA VALLEY AND COLUMBIA BASIN. LOOKING AT THE PAST
FEW RUNS OF THE HRRR IT APPEARS THAT THE STRONGEST WIND TODAY WILL
BE OVER THE YAKIMA VALLEY AND SIMCOE HIGHLANDS WITH GUST POTENTIAL
REACHING 50 TO 55 MPH LATE THIS MORNING INTO EARLY THIS AFTERNOON.
THIS MAKES SENSE BECAUSE THIS AREA IS CLOSER TO THE TRACK OF THE
UPPER TROUGH. WINDS WILL DECREASE QUICKLY BY EARLY EVENING. AS A
SECOND UPPER TROUGH APPROACHES LATER TONIGHT RAIN IS EXPECTED TO
SPREAD EAST OF THE CASCADES. THIS RAIN WILL MOVE ACROSS THE ENTIRE
FORECAST AREA ON SUNDAY. BUMPED UP POPS QUITE A BIT FOR SUNDAY TO
REFLECT THE MODELS WETTER TRENDING...AND POPS MAY NEED TO BE RAISED
FURTHER. THERE IS A CHANCE FOR QUARTER INCH AMOUNTS WITH THIS SYSTEM
OVER A WIDE AREA WHICH WOULD REALLY HELP WITH THE ONGOING FIRES. BY
MONDAY THE TROUGH WILL HAVE MOVED EAST OF THE REGION WITH GENERALLY
DRY CONDITIONS AND COOL TEMPERATURES. 78
.LONG TERM...MONDAY NIGHT THROUGH SATURDAY..THE AREA WILL BE UNDER
THE INFLUENCE OF AN UPPER LEVEL TROUGH THROUGH THE LONG TERM PERIOD
AND UNSETTLED WEATHER IS EXPECTED. ON MONDAY NIGHT THE TROUGH WILL
BE BROAD AND SHALLOW WITH A WESTERLY FLOW OVER THE AREA. AN UPPER
LOW WILL BE OFF THE NORTHERN BRITISH COLUMBIA COAST AND WILL SINK
SOUTH, ENDING UP NEAR NORTHERN VANCOUVER ISLAND BY TUESDAY
AFTERNOON. RAIN SHOWERS WILL STRUGGLE TO GET VERY FAR PAST THE
CASCADE CREST THOUGH BY TUESDAY AFTERNOON, THERE SHOULD BE A FEW
LIGHT SHOWERS AS FAR EAST AS YAKIMA AND ELLENSBURG. THE REST OF THE
AREA WILL REMAIN DRY. WINDS WILL BECOME BREEZY TUESDAY AFTERNOON.
THE UPPER LOW WILL DEEPEN THE TROUGH AND TURN THE FLOW OVER OUR AREA
MORE SOUTHWESTERLY. A FRONT WILL MOVE THROUGH THE AREA TUESDAY NIGHT
AND WEDNESDAY BRINGING A CHANCE OF LIGHT RAIN TO THE ENTIRE AREA.
ANOTHER IMPULSE WILL MOVE THROUGH THE TROUGH ON THURSDAY AND BRING A
CHANCE OF RAIN AND A SLIGHT CHANCE OF THUNDERSTORMS TO THE MOUNTAINS
WITH A SLIGHT CHANCE OF RAIN IN CENTRAL OREGON AND THE BLUE MOUNTAIN
FOOTHILLS. THE GFS SHOWS THE IMPULSE CARVING THE TROUGH FURTHER
SOUTH ON FRIDAY WITH A SLIGHT CHANCE OF THUNDERSTORMS IN THE EASTERN
MOUNTAINS. THE ECMWF IS LESS VIGOROUS WITH THIS IMPULSE AND DOES NOT
SHOW ANY PRECIPITATION BUT DOES DEEPEN THE TROUGH SOMEWHAT. HAVE
LEANED TOWARDS THE GFS AND PUT A SLIGHT CHANCE OF THUNDERSTORMS IN
THE EASTERN MOUNTAINS. ON SATURDAY, BOTH MODELS SHOW THE TROUGH
STARTING TO MOVE EASTWARD WITH A SLIGHT CHANCE OF THUNDERSTORMS
MAINLY IN WALLOWA COUNTY AND THE HIGHER TERRAIN IN THE REST OF THE
EASTERN MOUNTAINS. TUESDAY WILL SEE TEMPERATURES IN THE 70S AND
LOWER 80S. WEDNESDAY AND THURSDAY WILL BE COOLER WITH HIGHS IN THE
MID 60S TO MID 70S. FRIDAY AND SATURDAY WILL SEE TEMPERATURES BACK
IN THE MID 70S TO LOWER 80S WITH MID 60S TO MID 70S IN THE
MOUNTAINS. PERRY
&&
.AVIATION...PREVIOUS DISCUSSION...06Z TAFS...VFR CONDITIONS WILL
CONTINUE FOR THE NEXT 24 HOURS BUT ARE EXPECTING A FRONTAL PASSAGE
EARLY TO MIDDAY SATURDAY. CEILINGS WILL BE BROKEN TO OVERCAST AT 8K-
12K FEET AGL BUT AGAIN COULD SEE SOME LOWER CEILINGS AROUND FRONTAL
PASSAGE TIME. SMOKE FROM REGIONAL WILDFIRES WILL CONTINUE TO BE
PRESENT ACROSS THE AREA BUT ARE NOT EXPECTED TO LOWER VISIBILITIES
TO MVFR AT ANY TAF SITE. SHOWERS WILL DEVELOP ALONG THE FRONT AND
APPROACH THE CASCADES AFTER 10Z BUT THE PROBABILITY OF RAIN SHOWERS
AT ANY TAF SITE IS FAIRLY LOW DUE TO RAIN SHADOWING. A SIGNIFICANT
WIND INCREASE IS EXPECTED WITH THE FRONTAL PASSAGE ON SATURDAY OF 20-
30 KTS AND HIGHER GUST RESULTING IN BLOWING DUST AND REDUCED SURFACE
VISIBILITIES. 91/93
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 81 54 72 50 / 10 10 50 10
ALW 83 61 73 54 / 10 10 60 10
PSC 83 58 76 56 / 10 10 60 10
YKM 74 53 70 48 / 20 50 40 10
HRI 85 57 74 53 / 10 10 50 10
ELN 74 53 72 50 / 30 50 50 10
RDM 77 48 67 39 / 20 10 50 10
LGD 83 47 69 46 / 20 10 50 10
GCD 82 46 71 36 / 10 10 40 10
DLS 80 61 75 56 / 30 70 70 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WIND ADVISORY FROM 5 AM EARLY THIS MORNING TO 6 PM PDT THIS
EVENING FOR ORZ510-511.
RED FLAG WARNING FROM 7 AM THIS MORNING TO 7 PM PDT THIS EVENING
FOR ORZ640>645.
BLOWING DUST ADVISORY FROM 9 AM THIS MORNING TO 6 PM PDT THIS
EVENING FOR ORZ044-507-508.
WIND ADVISORY FROM 9 AM THIS MORNING TO 6 PM PDT THIS EVENING
FOR ORZ044-507-508.
WA...RED FLAG WARNING FROM 7 AM THIS MORNING TO 7 PM PDT THIS EVENING
FOR WAZ641-643-645-675.
BLOWING DUST ADVISORY FROM 9 AM THIS MORNING TO 6 PM PDT THIS
EVENING FOR WAZ027>029.
WIND ADVISORY FROM 9 AM THIS MORNING TO 6 PM PDT THIS EVENING
FOR WAZ027>029-521.
&&
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
78/83/83
AREA FORECAST DISCUSSION...UPDATED
NWS PORTLAND OR
938 PM PDT FRI AUG 28 2015
UPDATED AVIATION AND MARINE DISCUSSIONS.
.SYNOPSIS...AN USUALLY EARLY AND STRONG LOW PRESSURE WILL PRODUCE
WIDESPREAD RAIN AND STRONG WINDS ACROSS NORTHWEST OREGON AND
SOUTHWEST WASHINGTON SATURDAY MORNING. A FEW THUNDERSTORMS EMBEDDED
IN THE RAIN MAY ENHANCE THE WIND THREAT SATURDAY MORNING. A SECOND
FRONT PUSHING INTO THE REGION FROM THE NORTHWEST SATURDAY NIGHT WILL
PRODUCE ANOTHER ROUND OF RAIN. ADDITIONAL SHOWERS WILL FOLLOW ON
SUNDAY. EXPECT COOL WEATHER AND ADDITIONAL ROUNDS OF SHOWERS FOR MUCH
OF THE UPCOMING WORK WEEK.
&&
.SHORT TERM...VISIBLE AND INFRARED SATELLITE IMAGERY SHOW AN
IMPRESSIVE SURFACE LOW PRESSURE UNDERGOING CYCLOGENESIS OFF THE
SOUTHERN OREGON COAST NEAR 130W. BUOY 46002 SLP CONTINUES TO DROP
BETWEEN 2-3MB/HOUR AND OUTPACE THE GFS AND EC FORECASTS CONSIDERABLY.
THE 00Z NAM SEEMS TO HAVE PICKED UP ON THIS ADDITIONAL DEVELOPMENT
AND IS AT LEAST CLOSER TO REALITY THAN THE 18Z GFS AND 12Z EC RUNS AT
THIS POINT. THE NAM FORECASTS THE LOW TO BOTTOM OUT AROUND 990MB OFF
THE MOUTH OF THE COLUMBIA RIVER AROUND 15Z SATURDAY BEFORE CLIPPING
CAPE FLATTERY ON ITS WAY NORTHWARD. SUSPECT IT WILL DROP SOLIDLY INTO
THE 980S. MEANWHILE...THE EC AND GFS HAVE CONTINUED TO TREND TOWARDS
GRADUALLY SHIFTING THE LOW TRACK SLIGHTLY FARTHER OFFSHORE...WHICH
EVEN WITH THE DEEPER DEVELOPMENT OBSERVED SO FAR...SHOULD HELP TO
KEEP THIS STORM FROM REALIZING ITS FULLEST POTENTIAL IN THE
WILLAMETTE VALLEY AND LOWER COLUMBIA RIVER VALLEY. WITH THAT
SAID...THE RAP BRINGS THE LOW PRESSURE ONSHORE OVER THE OLYMPIC
PENINSULA. THE RAP DID A DECENT JOB DEPICTING THE TRACK OF SEVERAL OF
OUR STRONGER LOW PRESSURES LAST YEAR SO IT IS TOUGH TO DISCOUNT IT
EVEN THOUGH IT IS CONSIDERABLY DIFFERENT THAN THE GLOBAL GFS AND EC
MODEL SOLUTIONS. GIVEN THE UNCERTAINTY IN THE FINAL TRACK OF THIS
LOW...ALL THE INHERITED HEADLINES SEEM REASONABLE AT THIS POINT.
HOWEVER...WILL NUDGE UP THE MENTION OF WIND GUSTS ALONG THE NORTH
OREGON AND SOUTH WASHINGTON COASTS AND ACROSS THE LOWER COLUMBIA
RIVER VALLEY AND PORTLAND METRO AREA WHERE A FEW HIGHER WIND GUSTS
SEEM POSSIBLE...ESPECIALLY IF THE LOW PRESSURE PUSHES ONTO THE
WASHINGTON COAST.
EXPECT THE WINDS TO COME ON RATHER SUDDENLY SATURDAY MORNING. THE
STRONG BURST OF WINDS SHOULD FIRST HIT THE CENTRAL OREGON COAST
BETWEEN 4 AM AND 6 AM...AND THE NORTH OREGON COAST...THE SOUTH
WASHINGTON COAST...AND THE WILLAMETTE VALLEY BETWEEN 7 AM AND 10 AM.
WHILE WINDS WILL STILL BE NOTABLY GUSTY SATURDAY AFTERNOON...THE
STRONGEST WINDS WILL LIKELY ONLY LAST FOR 2 TO 4 HOURS.
IN ADDITION...EXPANDED THE MENTION OF THUNDER TO A LARGER PORTION OF
THE CWA FOR SATURDAY MORNING AS THE NAM CONTINUES TO ADVERTISE
SUFFICIENT INSTABILITY TO PRODUCE A THUNDERSTORM OR TWO ALONG THE
FRONT. GIVEN THE AMPLE SHEAR...ANY STORMS THAT DO DEVELOP WILL NEED
TO BE MONITORED CLOSELY FOR PRODUCING LOCALIZED DAMAGING WINDS.
WHILE MOST EVERYONE SHOULD SEE A QUICK SHOT OF RAIN LATER TONIGHT AND
SATURDAY MORNING...SUSPECT TOMORROW WILL BE MORE DRY THAN WET FOR
MANY. HOWEVER...NOT ALL IS LOST AS MODELS HAVE TRENDED WETTER WITH A
SECOND FRONT DROPPING SOUTHEASTWARD OUT OF THE GULF OF ALASKA THAT
WILL PUSH A HEALTHY DOSE OF RAIN ACROSS THE AREA SATURDAY NIGHT.
DECENT ONSHORE FLOW AND INSTABILITY SHOULD LEAD TO MORE SHOWERS AND
POSSIBLY A WET THUNDERSTORM OR TWO SUNDAY.
BELOW AVERAGE TEMPERATURES AND ADDITIONAL ROUNDS OF WET WEATHER
APPEAR LIKELY NEXT WEEK. /NEUMAN
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY. THE FALL-LIKE WEATHER
PATTERN WILL CONTINUE NEXT WEEK WITH PRIMARILY COOLER THAN NORMAL
TEMPERATURES...CLOUDY CONDITIONS...AND CHANCES FOR ADDITIONAL RAIN. A
TROUGH WILL REMAIN NEAR THE PACIFIC NORTHWEST COAST THROUGH MOST OF
THE PERIOD WITH SOME RAIN AT TIMES...ESPECIALLY DURING THE EARLY AND
MIDDLE PARTS OF NEXT WEEK. LITTLE CHANGE MADE TO THE CURRENT
FORECAST. TOLLESON
&&
.AVIATION...VFR CONDITIONS CONTINUE ACROSS THE REGION WITH LIGHT
DRIZZLE STARTING TO MOVE IN ALONG THE COAST. EXPECT CIGS ALONG THE
COAST TO LOWER TOWARDS MVFR OVER THE NEXT SEVERAL HOURS AS RAIN
CHANCES INCREASE. BRIEF PERIODS OF IFR CIGS AND VSBY WILL BE
POSSIBLE UNDER MODERATE TO HEAVY RAIN. RAIN WILL MOVE INLAND AFTER
09Z AND COULD BRING LOWER CIGS AND VSBY TO THE INTERIOR TAF SITES
THROUGH MUCH OF SATURDAY. SOUTHERLY WINDS ALONG THE COAST WILL
INCREASE AROUND 09Z-12Z ALONG THE CENTRAL OREGON COAST AND 12Z
TO 15Z ALONG THE NORTH OREGON COAST...WITH GUSTS UP TO 35 TO 45
KT. SOUTHERLY WINDS AT INLAND SITES START TO INCREASE AROUND 11 TO
13Z WITH GUSTS TO 25 TO 35 KT AND OCCASIONALLY TO 40 KT.
KPDX AND APPROACHES...VFR THROUGH TONIGHT. RAIN CHANCES INCREASE
AFTER 09Z WITH BRIEF PERIODS OF MVFR CIGS AND VSBY POSSIBLE UNDER
MODERATE TO HEAVY RAIN BANDS. SOUTHERLY WINDS INCREASE AROUND 11Z
WITH GUSTS TO 25 TO 35 KT AND OCCASIONAL GUST TO 40 KT POSSIBLE.
/64/MCCOY
&&
.MARINE...A STRENGTHENING FALL-LIKE LOW PRESSURE SYSTEM WILL MOVE
ACROSS THE WATERS SATURDAY. WINDS WILL INCREASE OUT OF THE SOUTH
TO AT LEAST HIGH-END GALES. MODELS HAVE CONTINUED THE UPWARD
TREND IN THE WINDS...WHICH COULD BRING A FEW HOURS OF ISOLATED
STORM FORCE GUSTS LATE SATURDAY MORNING...BUT CONFIDENCE IN THE
DURATION AND EXTENT OF THE STRONGEST WINDS REMAIN TOO LOW TO
UPGRADE TO A STORM WARNING. SEAS CURRENTLY AROUND 4 FT WILL BUILD
RAPIDLY TO 15 TO 17 FT...AND POSSIBLY AS HIGH AS 20 TO 25 FT...AS
THE WINDS INCREASE EARLY SATURDAY MORNING. SEAS WILL REMAIN
ELEVATED THROUGH LATE SATURDAY. WINDS SHIFT MORE TO THE SOUTH-
SOUTHWEST BY SATURDAY EVENING AND FALL BACK DOWN TO 15 KT GUSTING
TO 20 TO 25 KT BY SUNDAY MORNING. SEAS ON SUNDAY WILL BE AROUND 8
TO 10 FT AS WINDS CONTINUE TO DECREASE TO 10 TO 15 KT BY SUNDAY
EVENING.
UNSETTLED WEATHER CONTINUES INTO NEXT WEEK WITH SEAS STAYING
AROUND 7 TO 9 FT THROUGH AT LEAST MIDWEEK. /64/MCCOY
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WIND ADVISORY FROM 8 AM TO 3 PM PDT SATURDAY FOR GREATER
PORTLAND METRO AREA-LOWER COLUMBIA.
HIGH WIND WARNING FROM 4 AM TO 1 PM PDT SATURDAY FOR CENTRAL
OREGON COAST.
WIND ADVISORY FROM 6 AM TO NOON PDT SATURDAY FOR CENTRAL
WILLAMETTE VALLEY-SOUTH WILLAMETTE VALLEY.
HIGH WIND WARNING FROM 6 AM TO 2 PM PDT SATURDAY FOR COAST
RANGE OF NORTHWEST OREGON-NORTH OREGON COAST.
HIGH WIND WARNING FROM 5 AM TO NOON PDT SATURDAY FOR CENTRAL
COAST RANGE OF WESTERN OREGON.
WA...WIND ADVISORY FROM 8 AM TO 3 PM PDT SATURDAY FOR GREATER
VANCOUVER AREA-I-5 CORRIDOR IN COWLITZ COUNTY.
HIGH WIND WARNING FROM 8 AM TO 3 PM PDT SATURDAY FOR WILLAPA
HILLS.
HIGH WIND WARNING FROM 8 AM TO 2 PM PDT SATURDAY FOR SOUTH
WASHINGTON COAST.
PZ...GALE WARNING FROM 3 AM SATURDAY TO MIDNIGHT PDT SATURDAY
NIGHT FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 AM
SATURDAY TO MIDNIGHT PDT SATURDAY NIGHT.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS PORTLAND OR
901 PM PDT FRI AUG 28 2015
.SYNOPSIS...AN USUALLY EARLY AND STRONG LOW PRESSURE WILL PRODUCE
WIDESPREAD RAIN AND STRONG WINDS ACROSS NORTHWEST OREGON AND
SOUTHWEST WASHINGTON SATURDAY MORNING. A FEW THUNDERSTORMS EMBEDDED
IN THE RAIN MAY ENHANCE THE WIND THREAT SATURDAY MORNING. A SECOND
FRONT PUSHING INTO THE REGION FROM THE NORTHWEST SATURDAY NIGHT WILL
PRODUCE ANOTHER ROUND OF RAIN. ADDITIONAL SHOWERS WILL FOLLOW ON
SUNDAY. EXPECT COOL WEATHER AND ADDITIONAL ROUNDS OF SHOWERS FOR MUCH
OF THE UPCOMING WORK WEEK.
&&
.SHORT TERM...VISIBLE AND INFRARED SATELLITE IMAGERY SHOW AN
IMPRESSIVE SURFACE LOW PRESSURE UNDERGOING CYCLOGENESIS OFF THE
SOUTHERN OREGON COAST NEAR 130W. BUOY 46002 SLP CONTINUES TO DROP
BETWEEN 2-3MB/HOUR AND OUTPACE THE GFS AND EC FORECASTS CONSIDERABLY.
THE 00Z NAM SEEMS TO HAVE PICKED UP ON THIS ADDITIONAL DEVELOPMENT
AND IS AT LEAST CLOSER TO REALITY THAN THE 18Z GFS AND 12Z EC RUNS AT
THIS POINT. THE NAM FORECASTS THE LOW TO BOTTOM OUT AROUND 990MB OFF
THE MOUTH OF THE COLUMBIA RIVER AROUND 15Z SATURDAY BEFORE CLIPPING
CAPE FLATTERY ON ITS WAY NORTHWARD. SUSPECT IT WILL DROP SOLIDLY INTO
THE 980S. MEANWHILE...THE EC AND GFS HAVE CONTINUED TO TREND TOWARDS
GRADUALLY SHIFTING THE LOW TRACK SLIGHTLY FARTHER OFFSHORE...WHICH
EVEN WITH THE DEEPER DEVELOPMENT OBSERVED SO FAR...SHOULD HELP TO
KEEP THIS STORM FROM REALIZING ITS FULLEST POTENTIAL IN THE
WILLAMETTE VALLEY AND LOWER COLUMBIA RIVER VALLEY. WITH THAT
SAID...THE RAP BRINGS THE LOW PRESSURE ONSHORE OVER THE OLYMPIC
PENINSULA. THE RAP DID A DECENT JOB DEPICTING THE TRACK OF SEVERAL OF
OUR STRONGER LOW PRESSURES LAST YEAR SO IT IS TOUGH TO DISCOUNT IT
EVEN THOUGH IT IS CONSIDERABLY DIFFERENT THAN THE GLOBAL GFS AND EC
MODEL SOLUTIONS. GIVEN THE UNCERTAINTY IN THE FINAL TRACK OF THIS
LOW...ALL THE INHERITED HEADLINES SEEM REASONABLE AT THIS POINT.
HOWEVER...WILL NUDGE UP THE MENTION OF WIND GUSTS ALONG THE NORTH
OREGON AND SOUTH WASHINGTON COASTS AND ACROSS THE LOWER COLUMBIA
RIVER VALLEY AND PORTLAND METRO AREA WHERE A FEW HIGHER WIND GUSTS
SEEM POSSIBLE...ESPECIALLY IF THE LOW PRESSURE PUSHES ONTO THE
WASHINGTON COAST.
EXPECT THE WINDS TO COME ON RATHER SUDDENLY SATURDAY MORNING. THE
STRONG BURST OF WINDS SHOULD FIRST HIT THE CENTRAL OREGON COAST
BETWEEN 4 AM AND 6 AM...AND THE NORTH OREGON COAST...THE SOUTH
WASHINGTON COAST...AND THE WILLAMETTE VALLEY BETWEEN 7 AM AND 10 AM.
WHILE WINDS WILL STILL BE NOTABLY GUSTY SATURDAY AFTERNOON...THE
STRONGEST WINDS WILL LIKELY ONLY LAST FOR 2 TO 4 HOURS.
IN ADDITION...EXPANDED THE MENTION OF THUNDER TO A LARGER PORTION OF
THE CWA FOR SATURDAY MORNING AS THE NAM CONTINUES TO ADVERTISE
SUFFICIENT INSTABILITY TO PRODUCE A THUNDERSTORM OR TWO ALONG THE
FRONT. GIVEN THE AMPLE SHEAR...ANY STORMS THAT DO DEVELOP WILL NEED
TO BE MONITORED CLOSELY FOR PRODUCING LOCALIZED DAMAGING WINDS.
WHILE MOST EVERYONE SHOULD SEE A QUICK SHOT OF RAIN LATER TONIGHT AND
SATURDAY MORNING...SUSPECT TOMORROW WILL BE MORE DRY THAN WET FOR
MANY. HOWEVER...NOT ALL IS LOST AS MODELS HAVE TRENDED WETTER WITH A
SECOND FRONT DROPPING SOUTHEASTWARD OUT OF THE GULF OF ALASKA THAT
WILL PUSH A HEALTHY DOSE OF RAIN ACROSS THE AREA SATURDAY NIGHT.
DECENT ONSHORE FLOW AND INSTABILITY SHOULD LEAD TO MORE SHOWERS AND
POSSIBLY A WET THUNDERSTORM OR TWO SUNDAY.
BELOW AVERAGE TEMPERATURES AND ADDITIONAL ROUNDS OF WET WEATHER
APPEAR LIKELY NEXT WEEK. /NEUMAN
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY. THE FALL-LIKE WEATHER
PATTERN WILL CONTINUE NEXT WEEK WITH PRIMARILY COOLER THAN NORMAL
TEMPERATURES...CLOUDY CONDITIONS...AND CHANCES FOR ADDITIONAL RAIN. A
TROUGH WILL REMAIN NEAR THE PACIFIC NORTHWEST COAST THROUGH MOST OF
THE PERIOD WITH SOME RAIN AT TIMES...ESPECIALLY DURING THE EARLY AND
MIDDLE PARTS OF NEXT WEEK. LITTLE CHANGE MADE TO THE CURRENT
FORECAST. TOLLESON
&&
.AVIATION...VFR CONDITIONS ACROSS THE AREA WITH CIGS PRIMARILY UP
ABOVE 10KFT. CIGS ALONG THE COAST WILL LOWER TO MVFR THIS EVENING
AROUND 03Z AS MORE SUBSTANTIAL SHOWERS MAKE THERE WAY ONTO THE
COAST. EXPECT MVFR CIGS TO CONTINUE OVERNIGHT WITH OCCASIONAL
DROPS IN VIS WITH HEAVIER SHOWERS. SHOWERS MOVES INLAND AROUND
08Z WHICH WILL LOWER CIGS AT INLAND TAF SITES TO LOW VFR...
OCCASIONALLY DROPPING TO MVFR THROUGH SATURDAY MORNING. SOUTHERLY
WINDS
ALONG THE COAST WILL INCREASE AROUND 09Z-12Z ALONG THE CENTRAL
OREGON COAST AND 12Z TO 15Z ALONG THE NORTH OREGON COAST...WITH
GUSTS UP TO 35 TO 45 KT. SOUTHERLY WINDS AT INLAND SITES START TO
INCREASE AROUND 11 TO 13Z WITH GUSTS TO 25 TO 35 KT AND
OCCASIONALLY TO 40 KT.
KPDX AND APPROACHES...VFR THIS EVENING. MORE WIDESPREAD SHOWERS
MOVE IN AROUND 08Z LOWERING CIGS TO LOW VFR WITH OCCASIONAL DROPS
TO MVFR. SOUTHERLY WINDS INCREASE AROUND 11Z WITH GUSTS TO 25 TO
35 KT AND OCCASIONAL GUST TO 40 KT POSSIBLE. -MCCOY
&&
.MARINE...FALL-LIKE LOW PRESSURE SYSTEM APPROACHES FROM APPROX 400
MI WEST OF NORTHERN CALIFORNIA. AS IT MOVES INTO THE WATERS EARLY
SATURDAY MORNING. WINDS WILL INCREASE OUT OF THE SOUTH TO AT LEAST
HIGH END GALES. MODELS HAVE STARTED TRENDING STRONGER...WHICH MAY
INDICATE AT LEAST A FEW STORM FORCE GUSTS...BUT WOULD LIKE TO SEE
ANOTHER RUN DEPICTING THIS SCENARIO BEFORE CONFIDENCE IMPROVES
ENOUGH TO UPGRADE TO STORM WARNING. AS WINDS INCREASE...SEAS WHICH
WILL BE AROUND 4 TO 5 FT TONIGHT THROUGH EARLY SATURDAY MORNING
WILL RAPIDLY BUILD TO 15 TO 17 FT. SEAS STAY UP AROUND 13 TO 17
FT UNTIL WINDS DECREASE SATURDAY EVENING. WINDS SHIFT MORE TO THE
SOUTH-SOUTHWEST BY SATURDAY EVENING AND FALL BACK DOWN TO 15 KT
GUSTING TO 20 TO 25 KT BY SUNDAY MORNING. SEAS ON SUNDAY WILL BE
AROUND 8 TO 10 FT WITH WINDS WITH WINDS DECREASING FURTHER TO 10
TO 15 KT BY SUNDAY EVENING.
UNSETTLED WEATHER CONTINUES INTO NEXT WEEK WITH SEAS STAYING
AROUND 7 TO 9 FT THROUGH AT LEAST MIDWEEK. -MCCOY
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WIND ADVISORY FROM 8 AM TO 3 PM PDT SATURDAY FOR GREATER
PORTLAND METRO AREA-LOWER COLUMBIA.
HIGH WIND WARNING FROM 4 AM TO 1 PM PDT SATURDAY FOR CENTRAL
OREGON COAST.
WIND ADVISORY FROM 6 AM TO NOON PDT SATURDAY FOR CENTRAL
WILLAMETTE VALLEY-SOUTH WILLAMETTE VALLEY.
HIGH WIND WARNING FROM 6 AM TO 2 PM PDT SATURDAY FOR COAST RANGE
OF NORTHWEST OREGON-NORTH OREGON COAST.
HIGH WIND WARNING FROM 5 AM TO NOON PDT SATURDAY FOR CENTRAL
COAST RANGE OF WESTERN OREGON.
WA...WIND ADVISORY FROM 8 AM TO 3 PM PDT SATURDAY FOR GREATER
VANCOUVER AREA-I-5 CORRIDOR IN COWLITZ COUNTY.
HIGH WIND WARNING FROM 8 AM TO 3 PM PDT SATURDAY FOR WILLAPA
HILLS.
HIGH WIND WARNING FROM 8 AM TO 2 PM PDT SATURDAY FOR SOUTH
WASHINGTON COAST.
PZ...GALE WARNING FROM 3 AM SATURDAY TO MIDNIGHT PDT SATURDAY NIGHT
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60
NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 AM
SATURDAY TO MIDNIGHT PDT SATURDAY NIGHT.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1002 PM EDT SUN AUG 30 2015
.SYNOPSIS...
A WEAK TROUGH DYING OVER THE REGION AND HIGH MOISTURE WILL RESULT
IN A FEW SHOWERS OVER MAINLY SOUTHERN PORTIONS OF CENTRAL
PENNSYLVANIA OVERNIGHT. SHOWERS WILL PERSIST ACROSS THE SOUTH
MONDAY MORNING...WHILE NORTHERN AREAS ARE MAINLY DRY. HOWEVER...
A PASSING AFTERNOON SHOWER OR THUNDERSTORM WILL BE POSSIBLE JUST
ABOUT ANYWHERE. HIGH PRESSURE OFF THE EAST COAST WILL LEAD TO
TEMPERATURES WELL ABOVE NORMALS ALL WEEK...WITH HIGH HUMIDITY...
AND AT LEAST A SLIGHT CHANCE OF AN AFTERNOON SHOWER OR
THUNDERSTORM EACH DAY. IT WILL FEEL MORE LIKE THE MIDDLE OF SUMMER
THAN SEPTEMBER.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
SHOWERS HAVE DWINDLED TO ISOLATED COVERAGE ACROSS THE SOUTH
CENTRAL MOUNTAINS AND MIDDLE SUSQUEHANNA RIVER VALLEY AT THIS
HOUR. WEAK DEFORMATION AND BOUNDARY LAYER MOISTURE CONVERGENCE IN
THIS REGION SUPPORT ISOLATED ACTIVITY THROUGH 06Z...ALTHOUGH MOST
AREAS FROM THE CENTRAL AND SOUTH CENTRAL MOUNTAINS EASTWARD WILL
REMAIN DRY.
FARTHER SOUTH...WEAK UPPER LOW OVER THE WESTERN CAROLINAS WILL
LIFT NORTHWARD OVERNIGHT ON THE WESTERN PERIPHERY OF THE SPRAWLING
WESTERN ATLANTIC UPPER HIGH CIRCULATION. THIS WILL MAINTAIN THE
FOCUS FOR POOLING MOISTURE AND FORCING FOR SHOWER ACTIVITY THROUGH
THE PRE DAWN HOURS ACROSS MY FAR SOUTH. MEANWHILE...AREAS TO THE
NORTH SHOULD BE DRY AFTER 06Z AS DEFORMATION LESSENS AND FORCING
FOCUS SHIFTS TO AREAS ALONG AND SOUTH OF MY SOUTHERN TIER.
PREVIOUS IDEA OF SHOWERS LINGERING LONGEST OVER THE SRN HALF OF
THE AREA GOOD AND ACTUALLY BUMPED POPS UP AS THE NIGHT WEARS ON
OVER MY SOUTHERN TIER COUNTIES. CLOUD COVER WILL BE GREATEST OVER
THE SOUTHERN THIRD TO HALF OF CENTRAL PA...WHILE THE NORTH SEES
PARTIAL CLEARING AND PEAKS OF THE NEARLY FULL MOON. SOME FOG MAY
DEVELOP...ESP IN PLACES WHICH HAD RAINFALL AND THOSE WHICH SEE
MORE CLEARING THAN OTHERS. MINS WILL RUN IN THE 60S EVERYWHERE
AS DEWPOINTS SHOULD NOT GO ANY LOWER THAN 60F.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
SUBSIDENCE DOES NOT REALLY COME DOWN SOUTH ENOUGH TO ALLOW US TO
DRY OUT ON MON. THE UPPER HIGH WILL CONTINUE TO SLIDE EASTWARD BUT
SOME SEMBLANCE OF TROFFINESS REMAINS ACCORDING TO MOST GUID. WITH
THE SFC HIGH RETURN FLOW INCREASING...A FEW SHRA/TSRA ARE STILL
POSSIBLE MON...BUT MAINLY IN THE FAR SOUTH AND FAR NORTH. HAVE
ALLOW FOR LINGERING SHRA S IN THE MORNING AND EARLY AFTN...AND
MORE IN THE WAY OF DIURNAL SHRA IN THE NRN TIER. MAXES WILL BE A
FEW DEGS HIGHER THAN TODAY - IF WE CAN GET RID OF MOST OF THE
CLOUDS FOR A SHORT TIME - BECAUSE 8H TEMPS WILL BE ABOUT 2C
WARMER.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
ANOMALOUS UPPER LEVEL RIDGE WILL DOMINATE THE OHIO VALLEY AND
EASTERN UNITED STATES MUCH OF THE UPCOMING WEEK...WITH LATEST
GUIDANCE REMAINING FIRM FOR AN EXTENDED RUN OF 850HPA TEMPS
PEAKING DAILY AROUND 16-18C. THIS WILL TRANSLATE TO WELL ABOVE-
NORMAL SFC TEMPS. THIS WARMTH AND INCREASING HUMIDITY SHOULD ALLOW
FOR AT LEAST A SLIGHT CHC FOR DIURNAL CONVECTION EACH DAY...BUT
WARM MID-LEVELS WILL KEEP THE PROBABILITY OF WIDESPREAD RAINFALL
QUITE LOW.
BEST CHANCES FOR PRECIP WILL BE MIDWEEK /WED-THU-FRI/ WITH A
COUPLE SUBTLE FEATURES. FIRST...A WEAK UPPER LEVEL WAVE /BEST
PROGGED ON THE ECMWF/ SLIPS OVERHEAD ON WED AS BERMUDA HIGH
BRIEFLY RECEDES. AT SAME TIME A WEAK BACKDOOR COLD FRONT SLIPS
SOUTHWARD OFF THE EAST COAST. THIS COULD HELP POOL SOME LOW LEVEL
MOISTURE OVER THE MID ATLANTIC AND OHIO VALLEY AS MID LEVELS COOL
JUST A BIT...BRINGING POTENTIAL FOR SCT TSTMS. RIDGE BUILDS BACK
IN FOR FRI...BUT ANOTHER SURFACE BACKDOOR FRONT TRIES TO SLIP
ACROSS THE STATE AS SURFACE HIGH EXPANDS IN FROM THE NORTH. THIS
BOUNDARY SHOULD BRING SCT CONVECTION FOR FRI.
EXTENDED MODELS HINT AT POTENTIAL FOR DAILY CONVECTION CONTINUING
INTO THE WEEKEND ALONG SOUTHER BORDER...BUT OVERALL CONDITIONS
WILL BE MAINLY RAIN-FREE.
TEMPS PEAK MIDWEEK WITH READINGS APPROACHING 90F IN THE SE...AND
EVEN GETTING INTO THE 80S ELSEHERE...EASILY WELL ABOVE NORMAL FOR
THE FIRST WEEK OF SEPT. LOWS WILL ALSO REMAIN QUITE MILD MID/LATE
WEEK AS HIGH HUMIDITY AIR HANGS AROUND. SLIGHTLY COOLER BUT STILL
ABOVE AVERAGE TEMPS WILL CONTINUE THROUGH THE WEEKEND.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
A WEAK AREA OF LOW PRESSURE PASSING TO THE NORTH OF PA HAS SPAWNED
SCT SHRA/TSRA ACROSS CENTRAL PA EARLY THIS EVENING. LOSS OF
HEATING SHOULD CAUSE MOST OF THE SHOWERS TO DISSIPATE SHORTLY
AFTER SUNSET. HOWEVER...RADAR TRENDS AND LATEST HRRR IMPLIES A
BRIEF VIS REDUCTION CAN/T BE RULED OUT AT KMDT/KLNS SOMETIME BTWN
01Z-04Z.
FOCUS LATER TONIGHT WILL SHIFT TOWARD POTENTIAL OF FOG. LIGHT WIND
AND PTCLDY SKIES SHOULD PROMOTE LOCALLY DENSE VALLEY FOG AFTER
MIDNIGHT ACROSS NORTHERN PA. CLIMATOLOGY AND LATEST SREF/MOS
SUGGEST KBFD IS LIKELY TO EXPERIENCE IFR/LIFR VIS REDUCTIONS
LATE TONIGHT. ALSO...MAY HAVE TO CONTEND WITH DENSE FOG AT
KIPT...WHERE GROUND IS NOW WET FROM A PASSING SHOWER. COMPLICATING
FACTOR IS MID LVL CLOUDINESS OVERSPREADING THE SOUTHERN PART OF
THE STATE. FEEL CONFIDENT THESE MID LVL CLOUDS WILL BE THICK
ENOUGH TO DIMINISH THE RADIATIONAL COOLING AND ASSOC DENSE FOG
THREAT ACROSS SOUTHERN PA. HOWEVER...NOT AS CONFIDENT AT KIPT.
ANY AM VALLEY FOG ACROSS NORTHERN PA SHOULD BURN OFF BY LATE AM.
OTHERWISE...WIDESPREAD VFR CONDS AND LIGHT WIND APPEAR VERY
LIKELY MONDAY WITH ONLY ISOLD LATE DAY SHRA/TSRA POSSIBLE...AS
HIGH PRESSURE BUILDS OFF THE MID ATLANTIC COAST.
OUTLOOK...
TUE-FRI...PATCHY AM FOG POSS...MAINLY KBFD. ISOLD PM TSRA IMPACTS
POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...DANGELO/DEVOIR
SHORT TERM...DANGELO
LONG TERM...RXR
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
959 PM EDT SUN AUG 30 2015
.SYNOPSIS...
A WEAK TROUGH DYING OVER THE REGION AND HIGH MOISTURE WILL RESULT
IN SCATTERED SHOWERS AND A FEW THUNDERSTORMS THIS EVENING.
DRIER WEATHER WILL OCCUR FOR THE FIRST PART OF THE WEEK...BUT
HIGH PRESSURE OFF THE EAST COAST WILL LEAD TO TEMPERATURES WELL
ABOVE NORMALS ALL WEEK...WITH HIGH HUMIDITY. IT WILL FEEL MORE
LIKE THE MIDDLE OF SUMMER THAN SEPTEMBER.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
SHOWERS HAVE DWINDLED TO ISOLATED COVERAGE ACROSS THE SOUTH
CENTRAL MOUNTAINS AND MIDDLE SUSQUEHANNA RIVER VALLEY AT THIS
HOUR. WEAK DEFORMATION AND BOUNDARY LAYER MOISTURE CONVERGENCE IN
THIS REGION SUPPORT ISOLATED ACTIVITY THROUGH 06Z...ALTHOUGH MOST
AREAS FROM THE CENTRAL AND SOUTH CENTRAL MOUNTAINS EASTWARD WILL
REMAIN DRY.
FARTHER SOUTH...WEAK UPPER LOW OVER THE WESTERN CAROLINAS WILL
LIFT NORTHWARD OVERNIGHT ON THE WESTERN PERIPHERY OF THE SPRAWLING
WESTERN ATLANTIC UPPER HIGH CIRCULATION. THIS WILL MAINTAIN THE
FOCUS FOR POOLING MOISTURE AND FORCING FOR SHOWER ACTIVITY THROUGH
THE PRE DAWN HOURS ACROSS MY FAR SOUTH. MEANWHILE...AREAS TO THE
NORTH SHOULD BE DRY AFTER 06Z AS DEFORMATION LESSENS AND FORCING
FOCUS SHIFTS TO AREAS ALONG AND SOUTH OF MY SOUTHERN TIER.
PREVIOUS IDEA OF SHOWERS LINGERING LONGEST OVER THE SRN HALF OF
THE AREA GOOD AND ACTUALLY BUMPED POPS UP AS THE NIGHT WEARS ON
OVER MY SOUTHERN TIER COUNTIES. CLOUD COVER WILL BE GREATEST OVER
THE SOUTHERN THIRD TO HALF OF CENTRAL PA...WHILE THE NORTH SEES
PARTIAL CLEARING AND PEAKS OF THE NEARLY FULL MOON. SOME FOG MAY
DEVELOP...ESP IN PLACES WHICH HAD RAINFALL AND THOSE WHICH SEE
MORE CLEARING THAN OTHERS. MINS WILL RUN IN THE 60S EVERYWHERE
AS DEWPOINTS SHOULD NOT GO ANY LOWER THAN 60F.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
SUBSIDENCE DOES NOT REALLY COME DOWN SOUTH ENOUGH TO ALLOW US TO
DRY OUT ON MON. THE UPPER HIGH WILL CONTINUE TO SLIDE EASTWARD BUT
SOME SEMBLANCE OF TROFFINESS REMAINS ACCORDING TO MOST GUID. WITH
THE SFC HIGH RETURN FLOW INCREASING...A FEW SHRA/TSRA ARE STILL
POSSIBLE MON...BUT MAINLY IN THE FAR SOUTH AND FAR NORTH. HAVE
ALLOW FOR LINGERING SHRA S IN THE MORNING AND EARLY AFTN...AND
MORE IN THE WAY OF DIURNAL SHRA IN THE NRN TIER. MAXES WILL BE A
FEW DEGS HIGHER THAN TODAY - IF WE CAN GET RID OF MOST OF THE
CLOUDS FOR A SHORT TIME - BECAUSE 8H TEMPS WILL BE ABOUT 2C
WARMER.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
ANOMALOUS UPPER LEVEL RIDGE WILL DOMINATE THE OHIO VALLEY AND
EASTERN UNITED STATES MUCH OF THE UPCOMING WEEK...WITH LATEST
GUIDANCE REMAINING FIRM FOR AN EXTENDED RUN OF 850HPA TEMPS
PEAKING DAILY AROUND 16-18C. THIS WILL TRANSLATE TO WELL ABOVE-
NORMAL SFC TEMPS. THIS WARMTH AND INCREASING HUMIDITY SHOULD ALLOW
FOR AT LEAST A SLIGHT CHC FOR DIURNAL CONVECTION EACH DAY...BUT
WARM MID-LEVELS WILL KEEP THE PROBABILITY OF WIDESPREAD RAINFALL
QUITE LOW.
BEST CHANCES FOR PRECIP WILL BE MIDWEEK /WED-THU-FRI/ WITH A
COUPLE SUBTLE FEATURES. FIRST...A WEAK UPPER LEVEL WAVE /BEST
PROGGED ON THE ECMWF/ SLIPS OVERHEAD ON WED AS BERMUDA HIGH
BRIEFLY RECEDES. AT SAME TIME A WEAK BACKDOOR COLD FRONT SLIPS
SOUTHWARD OFF THE EAST COAST. THIS COULD HELP POOL SOME LOW LEVEL
MOISTURE OVER THE MID ATLANTIC AND OHIO VALLEY AS MID LEVELS COOL
JUST A BIT...BRINGING POTENTIAL FOR SCT TSTMS. RIDGE BUILDS BACK
IN FOR FRI...BUT ANOTHER SURFACE BACKDOOR FRONT TRIES TO SLIP
ACROSS THE STATE AS SURFACE HIGH EXPANDS IN FROM THE NORTH. THIS
BOUNDARY SHOULD BRING SCT CONVECTION FOR FRI.
EXTENDED MODELS HINT AT POTENTIAL FOR DAILY CONVECTION CONTINUING
INTO THE WEEKEND ALONG SOUTHER BORDER...BUT OVERALL CONDITIONS
WILL BE MAINLY RAIN-FREE.
TEMPS PEAK MIDWEEK WITH READINGS APPROACHING 90F IN THE SE...AND
EVEN GETTING INTO THE 80S ELSEHERE...EASILY WELL ABOVE NORMAL FOR
THE FIRST WEEK OF SEPT. LOWS WILL ALSO REMAIN QUITE MILD MID/LATE
WEEK AS HIGH HUMIDITY AIR HANGS AROUND. SLIGHTLY COOLER BUT STILL
ABOVE AVERAGE TEMPS WILL CONTINUE THROUGH THE WEEKEND.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
A WEAK AREA OF LOW PRESSURE PASSING TO THE NORTH OF PA HAS SPAWNED
SCT SHRA/TSRA ACROSS CENTRAL PA EARLY THIS EVENING. LOSS OF
HEATING SHOULD CAUSE MOST OF THE SHOWERS TO DISSIPATE SHORTLY
AFTER SUNSET. HOWEVER...RADAR TRENDS AND LATEST HRRR IMPLIES A
BRIEF VIS REDUCTION CAN/T BE RULED OUT AT KMDT/KLNS SOMETIME BTWN
01Z-04Z.
FOCUS LATER TONIGHT WILL SHIFT TOWARD POTENTIAL OF FOG. LIGHT WIND
AND PTCLDY SKIES SHOULD PROMOTE LOCALLY DENSE VALLEY FOG AFTER
MIDNIGHT ACROSS NORTHERN PA. CLIMATOLOGY AND LATEST SREF/MOS
SUGGEST KBFD IS LIKELY TO EXPERIENCE IFR/LIFR VIS REDUCTIONS
LATE TONIGHT. ALSO...MAY HAVE TO CONTEND WITH DENSE FOG AT
KIPT...WHERE GROUND IS NOW WET FROM A PASSING SHOWER. COMPLICATING
FACTOR IS MID LVL CLOUDINESS OVERSPREADING THE SOUTHERN PART OF
THE STATE. FEEL CONFIDENT THESE MID LVL CLOUDS WILL BE THICK
ENOUGH TO DIMINISH THE RADIATIONAL COOLING AND ASSOC DENSE FOG
THREAT ACROSS SOUTHERN PA. HOWEVER...NOT AS CONFIDENT AT KIPT.
ANY AM VALLEY FOG ACROSS NORTHERN PA SHOULD BURN OFF BY LATE AM.
OTHERWISE...WIDESPREAD VFR CONDS AND LIGHT WIND APPEAR VERY
LIKELY MONDAY WITH ONLY ISOLD LATE DAY SHRA/TSRA POSSIBLE...AS
HIGH PRESSURE BUILDS OFF THE MID ATLANTIC COAST.
OUTLOOK...
TUE-FRI...PATCHY AM FOG POSS...MAINLY KBFD. ISOLD PM TSRA IMPACTS
POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...DANGELO/DEVOIR
SHORT TERM...DANGELO
LONG TERM...RXR
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
810 PM EDT SUN AUG 30 2015
.SYNOPSIS...
A WEAK TROUGH DYING OVER THE REGION AND HIGH MOISTURE WILL RESULT
IN SCATTERED SHOWERS AND A FEW THUNDERSTORMS THIS EVENING.
DRIER WEATHER WILL OCCUR FOR THE FIRST PART OF THE WEEK...BUT
HIGH PRESSURE OFF THE EAST COAST WILL LEAD TO TEMPERATURES WELL
ABOVE NORMALS ALL WEEK...WITH HIGH HUMIDITY. IT WILL FEEL MORE
LIKE THE MIDDLE OF SUMMER THAN SEPTEMBER.
&&
.NEAR TERM /UNTIL 11 PM THIS EVENING/...
TWO AREAS OF FORCING...ONE SHEAR AXIS ALONG THE PA/NY BORDER AND
ANOTHER OVER NORTHERN AND CENTRAL VIRGINIA...HAVE HELPED TO
INITIATE AND MAINTAIN ISOLATED TO SCATTERED COVERAGE OF SHOWERS
LATE THIS AFTERNOON INTO THE EARLY EVENING. A FEW LIGHTNING
STRIKES OCCURRING WITH ACTIVITY OVER ADAMS COUNTY...WHICH IS THE
MORE INTENSE AREA OF CONVECTION AT THIS TIME. STILL...CORES ARE
NOT VERY HIGH...AND AT THE PRESENT TIME BRIEF DOWNPOURS AND WIND
GUSTS OF 25 TO 30 MPH ARE ALL THAT WE EXPECT.
UPPED POPS SLIGHTLY AND EXPANDED COVERAGE INTO AREAS THAT WEREN`T
PREVIOUSLY INCLUDED. THINK THE IDEA OF SHOWERS LINGERING LONGEST
IN THE SRN HALF OF THE AREA AND ESP SE IS GOOD...AS A WEAK SFC
TROUGH SLIDES EAST BUT STALLS. CLOUD COVER IS A DIFFICULT FORECAST
WITH RH PLOTS SHOWING A DECENT AMOUNT OF LOWER CLOUDS HANGING ON
THROUGH THE NIGHT. THIS SEEMS REASONABLE SINCE THE WAVE DOES NOT
GO THROUGH AND WE DO NOT GET INTO SUBSTANTIAL SUBSIDENCE.
&&
.SHORT TERM /11 PM THIS EVENING THROUGH 6 PM MONDAY/...
CLOUD COVERAGE WILL LIKELY REMAIN THE MOST DIFFICULT PART OF THE
FORECAST OVERNIGHT. NAM RUNS A VERY SMALL PATCH OF LIGHT RAIN
THROUGH THE NW BY MORNING...MOST LIKELY ASSOCD WITH UPSTREAM
CONVECTION. AGAIN...NOT UNREASONABLE GIVEN THE HIGH MOISTURE AND
BEGINNING OF THE RETURN FLOW IN WRN PA. JUST THE FAR SRN TIER HAS
THE OTHER SLIGHT CHC FOR PRECIP OVERNIGHT AS THAT TROUGH LINGERS.
HOWEVER...FORCING AND INSTABILITY WILL BE LACKING THERE. SOME FOG
MAY DEVELOP...ESP IN PLACES WHICH HAD RAINFALL AND THOSE WHICH
SEE MORE CLEARING THAN OTHERS. HOWEVER...DO NOT EXPECT WIDESPREAD
FOG AT THIS POINT. MINS WILL RUN IN THE 60S EVERYWHERE AS
DEWPOINTS SHOULD NOT GO ANY LOWER THAN 60F.
SUBSIDENCE DOES NOT REALLY COME DOWN SOUTH ENOUGH TO ALLOW US TO
DRY OUT ON MON. THE UPPER HIGH WILL CONTINUE TO SLIDE EASTWARD BUT
SOME SEMBLANCE OF TROFFINESS REMAINS ACCORDING TO MOST GUID. WITH
THE SFC HIGH RETURN FLOW INCREASING...A FEW SHRA/TSRA ARE STILL
POSSIBLE MON...BUT MAINLY IN THE FAR SOUTH AND FAR NORTH. HAVE
ALLOW FOR LINGERING SHRA S IN THE MORNING AND EARLY AFTN...AND
MORE IN THE WAY OF DIURNAL SHRA IN THE NRN TIER. MAXES WILL BE A
FEW DEGS HIGHER THAN TODAY - IF WE CAN GET RID OF MOST OF THE
CLOUDS FOR A SHORT TIME - BECAUSE 8H TEMPS WILL BE ABOUT 2C
WARMER.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
ANOMALOUS UPPER LEVEL RIDGE WILL DOMINATE THE OHIO VALLEY AND
EASTERN UNITED STATES MUCH OF THE UPCOMING WEEK...WITH LATEST
GUIDANCE REMAINING FIRM FOR AN EXTENDED RUN OF 850HPA TEMPS
PEAKING DAILY AROUND 16-18C. THIS WILL TRANSLATE TO WELL ABOVE-
NORMAL SFC TEMPS. THIS WARMTH AND INCREASING HUMIDITY SHOULD ALLOW
FOR AT LEAST A SLIGHT CHC FOR DIURNAL CONVECTION EACH DAY...BUT
WARM MID-LEVELS WILL KEEP THE PROBABILITY OF WIDESPREAD RAINFALL
QUITE LOW.
BEST CHANCES FOR PRECIP WILL BE MIDWEEK /WED-THU-FRI/ WITH A
COUPLE SUBTLE FEATURES. FIRST...A WEAK UPPER LEVEL WAVE /BEST
PROGGED ON THE ECMWF/ SLIPS OVERHEAD ON WED AS BERMUDA HIGH
BRIEFLY RECEDES. AT SAME TIME A WEAK BACKDOOR COLD FRONT SLIPS
SOUTHWARD OFF THE EAST COAST. THIS COULD HELP POOL SOME LOW LEVEL
MOISTURE OVER THE MID ATLANTIC AND OHIO VALLEY AS MID LEVELS COOL
JUST A BIT...BRINGING POTENTIAL FOR SCT TSTMS. RIDGE BUILDS BACK
IN FOR FRI...BUT ANOTHER SURFACE BACKDOOR FRONT TRIES TO SLIP
ACROSS THE STATE AS SURFACE HIGH EXPANDS IN FROM THE NORTH. THIS
BOUNDARY SHOULD BRING SCT CONVECTION FOR FRI.
EXTENDED MODELS HINT AT POTENTIAL FOR DAILY CONVECTION CONTINUING
INTO THE WEEKEND ALONG SOUTHER BORDER...BUT OVERALL CONDITIONS
WILL BE MAINLY RAIN-FREE.
TEMPS PEAK MIDWEEK WITH READINGS APPROACHING 90F IN THE SE...AND
EVEN GETTING INTO THE 80S ELSEHERE...EASILY WELL ABOVE NORMAL FOR
THE FIRST WEEK OF SEPT. LOWS WILL ALSO REMAIN QUITE MILD MID/LATE
WEEK AS HIGH HUMIDITY AIR HANGS AROUND. SLIGHTLY COOLER BUT STILL
ABOVE AVERAGE TEMPS WILL CONTINUE THROUGH THE WEEKEND.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
A WEAK AREA OF LOW PRESSURE PASSING TO THE NORTH OF PA HAS SPAWNED
SCT SHRA/TSRA ACROSS CENTRAL PA EARLY THIS EVENING. LOSS OF
HEATING SHOULD CAUSE MOST OF THE SHOWERS TO DISSIPATE SHORTLY
AFTER SUNSET. HOWEVER...RADAR TRENDS AND LATEST HRRR IMPLIES A
BRIEF VIS REDUCTION CAN/T BE RULED OUT AT KMDT/KLNS SOMETIME BTWN
01Z-04Z.
FOCUS LATER TONIGHT WILL SHIFT TOWARD POTENTIAL OF FOG. LIGHT WIND
AND PTCLDY SKIES SHOULD PROMOTE LOCALLY DENSE VALLEY FOG AFTER
MIDNIGHT ACROSS NORTHERN PA. CLIMATOLOGY AND LATEST SREF/MOS
SUGGEST KBFD IS LIKELY TO EXPERIENCE IFR/LIFR VIS REDUCTIONS
LATE TONIGHT. ALSO...MAY HAVE TO CONTEND WITH DENSE FOG AT
KIPT...WHERE GROUND IS NOW WET FROM A PASSING SHOWER. COMPLICATING
FACTOR IS MID LVL CLOUDINESS OVERSPREADING THE SOUTHERN PART OF
THE STATE. FEEL CONFIDENT THESE MID LVL CLOUDS WILL BE THICK
ENOUGH TO DIMINISH THE RADIATIONAL COOLING AND ASSOC DENSE FOG
THREAT ACROSS SOUTHERN PA. HOWEVER...NOT AS CONFIDENT AT KIPT.
ANY AM VALLEY FOG ACROSS NORTHERN PA SHOULD BURN OFF BY LATE AM.
OTHERWISE...WIDESPREAD VFR CONDS AND LIGHT WIND APPEAR VERY
LIKELY MONDAY WITH ONLY ISOLD LATE DAY SHRA/TSRA POSSIBLE...AS
HIGH PRESSURE BUILDS OFF THE MID ATLANTIC COAST.
OUTLOOK...
TUE-FRI...PATCHY AM FOG POSS...MAINLY KBFD. ISOLD PM TSRA IMPACTS
POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...DANGELO/DEVOIR
SHORT TERM...DANGELO
LONG TERM...RXR
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1236 PM CDT SAT AUG 29 2015
.DISCUSSION...
UPDATED FOR 18Z AVIATION DISCUSSION
&&
.PREV DISCUSSION... /ISSUED 1124 AM CDT SAT AUG 29 2015/
UPDATE...
MUCH OF THE MIDSOUTH IS CURRENTLY STUCK BETWEEN TWO WEATHER
SYSTEMS. THE FIRST IS AN UPPER TROF THAT IS PUSHING ACROSS NORTH
CENTRAL ARKANSAS AT THIS TIME. AN AREA OF MAINLY SHOWERS IS
ACCOMPANYING THE TROF. HOWEVER THE AREA IS QUICKLY DYING OUT
EXPECT ONLY RANDOLPH AND LAWRENCE COUNTIES IN NORTHEAST ARKANSAS
WILL SEE ANY RAIN. MEANWHILE...AN EASTERLY WAVE IN MOVING THROUGH
ALABAMA. A LINE OF SHOWERS AND THUNDERSTORMS IS CURRENTLY
DEVELOPING ACROSS NORTHWEST ALABAMA. THIS LINE WILL MOVE SLOWLY
NORTHWESTWARD AND COULD IMPACT PORTIONS OF NORTHEAST MISSISSIPPI
THIS AFTERNOON. WILL BUMP UP POPS ACROSS THIS AREA.
OTHERWISE...REST OF THE FORECAST LOOKS GOOD. HIGHS WILL BE IN THE
UPPER 80S TO THE LOWER 90S THIS AFTERNOON.
KRM
PREV DISCUSSION... /ISSUED 440 AM CDT SAT AUG 29 2015/
UPDATE...
UPDATED TO INCREASE THE POPS FOR TODAY TO 40 PERCENT ACROSS
PORTIONS OF NORTHEAST AR THAT INCLUDES RANDOLPH...LAWRENCE AND
EXTREME WESTERN PORTIONS OF CLAY COUNTY. THE HRRR MODEL INDICATES
SHOWERS SPREADING INTO THIS AREA THIS MORNING. RADARS ALREADY
INDICATE SHOWERS JUST TO THE NORTHWEST GRADUALLY SLIPPING TO THE
SOUTHEAST.
JCL
DISCUSSION... /ISSUED 348 AM CDT SAT AUG 29 2015/
EARLY THIS MORNING...TEMPERATURES WERE A LITTLE WARMER THAN IN
RECENT DAYS RANGING FROM THE MIDDLE 60S TO LOWER 70S. MIDDLE AND
HIGH LEVEL CLOUDS STRETCHED FROM NORTHWEST TN AND THE MO BOOTHEEL
INTO NORTHEAST AR.
THE MIDSOUTH WILL BE AFFECTED BY TWO SYSTEMS THE NEXT COUPLE OF
DAYS...ONE AN UPPER LEVEL TROUGH APPROACHING FROM THE NORTHWEST
AND ANOTHER AN UPPER LEVEL LOW ALONG THE NORTHERN GULF COAST THAT
WILL LIFT NORTHEASTWARD. BOTH OF THESE FEATURES ARE FAIRLY WEAK.
THE LATEST GUIDANCE INDICATES HIGHER POPS ESPECIALLY FOR TONIGHT
AND SUNDAY THAN THE EARLIER GUIDANCE...DID RAISE THE POPS SOME BUT
CONFIDENCE IS NOT HIGH ENOUGH TO GO GREATER THAN 30 PERCENT POPS
ATTM. LATER FORECASTS MAY NEED TO RAISE THE POPS IN SOME LOCATIONS
DURING THIS TIMEFRAME.
FOR TODAY...AN UPPER LEVEL TROUGH FROM THE GREAT LAKES TO THE
CENTRAL PLAINS WILL MOVE SOUTHEASTWARD APPROACHING NORTHEAST AR.
INDICATED A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS FOR A SMALL
PORTION OF NORTHEAST AR TODAY. MEANWHILE...AN UPPER LEVEL LOW
WILL BE LOCATED ALONG THE MS AND AL COAST. THIS LOW WILL HELP TO
PUSH MORE MOIST AND UNSTABLE AIR INTO THE MIDSOUTH FROM THE EAST.
CONTINUED TO INDICATE A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS
FOR NORTHEAST MS AND THE TN RIVER VALLEY OF WEST TN. CLOUDS WILL
BE ON THE INCREASE ACROSS THE MIDSOUTH IN ASSOCIATION WITH BOTH OF
THESE SYSTEMS. TEMPERATURES WILL BE SEASONABLY WARM.
FOR TONIGHT...THE UPPER LEVEL TROUGH WILL PUSH INTO THE MIDSOUTH
FROM THE NORTHWEST WITH THE UPPER LOW ALONG THE CENTRAL GULF COAST
MOVING NORTHEASTWARD INTO CENTRAL AL. INDICATED A CHANCE OF
SHOWERS AND THUNDERSTORMS FOR MOST OF THE REGION.
ON SUNDAY...THE UPPER LEVEL LOW OVER CENTRAL AL WILL CONTINUE TO
PUSH NORTHEASTWARD WITH A WEAK BROAD UPPER LEVEL TROUGH OVER THE
MIDSOUTH. CONTINUED TO MENTION A CHANCE OF SHOWERS AND
THUNDERSTORMS. CLOUDS ARE EXPECTED TO DECREASE FROM THE SOUTHWEST.
MONDAY...AN UPPER LEVEL TROUGH WILL BE WEST OF THE MIDSOUTH WHILE
UPPER LEVEL RIDGING WILL BE TO THE EAST WITH WEAK SOUTHERLY FLOW
SURFACE AND ALOFT ACROSS THE REGION. THERE WILL BE ENOUGH MOISTURE
AND INSTABILITY FOR A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS.
IT WILL FEEL LIKE SUMMER WITH PLENTY OF SUNSHINE BOOSTING
TEMPERATURES TO NEAR NORMAL READINGS.
TUESDAY...THE UPPER LEVEL RIDGE IS FORECAST TO BUILD ACROSS THE
MIDSOUTH FROM THE EAST SUPPRESSING MOST CONVECTION. KEPT POPS
BELOW MENTIONABLE LEVELS.
TOWARD THE MIDDLE AND END OF NEXT WEEK...INCREASING MOISTURE IS
FORECAST TO SPREAD INTO THE REGION FROM THE SOUTHEAST AS UPPER
LEVEL RIDGING WEAKENS. THIS WILL RESULT IN A RETURN OF A SMALL
CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY. TEMPERATURES WILL
REMAIN SEASONABLY WARM TO HOT WITH NO COLD FRONTAL PASSAGES
EXPECTED.
JCL
&&
.AVIATION...
18Z TAF CYCLE
VFR. SHRAS WEST OF KJBR WILL CONTINUE TO DISSIPATE AS THEY MOVE
EAST TOWARD EASTERN ARKANSAS. ANOTHER DEVELOPING AREA OF
SHRA/TSRAS ACROSS NORTHWEST ALABAMA COULD PUSH NW INTO NORTHEAST
MISSISSIPPI THIS AFTERNOON THOUGH CONFIDENCE IS TOO LOW TO
MENTION VCTS/VCSH AT KTUP ATTM. SOUTH WINDS AROUND 8 KTS WILL
DIMINISH TO 5 KTS OR LESS OVERNIGHT.
SJM
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1124 AM CDT SAT AUG 29 2015
.UPDATE...
MUCH OF THE MIDSOUTH IS CURRENTLY STUCK BETWEEN TWO WEATHER
SYSTEMS. THE FIRST IS AN UPPER TROF THAT IS PUSHING ACROSS NORTH
CENTRAL ARKANSAS AT THIS TIME. AN AREA OF MAINLY SHOWERS IS
ACCOMPANYING THE TROF. HOWEVER THE AREA IS QUICKLY DYING OUT
EXPECT ONLY RANDOLPH AND LAWRENCE COUNTIES IN NORTHEAST ARKANSAS
WILL SEE ANY RAIN. MEANWHILE...AN EASTERLY WAVE IN MOVING THROUGH
ALABAMA. A LINE OF SHOWERS AND THUNDERSTORMS IS CURRENTLY
DEVELOPING ACROSS NORTHWEST ALABAMA. THIS LINE WILL MOVE SLOWLY
NORTHWESTWARD AND COULD IMPACT PORTIONS OF NORTHEAST MISSISSIPPI
THIS AFTERNOON. WILL BUMP UP POPS ACROSS THIS AREA.
OTHERWISE...REST OF THE FORECAST LOOKS GOOD. HIGHS WILL BE IN THE
UPPER 80S TO THE LOWER 90S THIS AFTERNOON.
KRM
&&
.PREV DISCUSSION... /ISSUED 440 AM CDT SAT AUG 29 2015/
UPDATE...
UPDATED TO INCREASE THE POPS FOR TODAY TO 40 PERCENT ACROSS
PORTIONS OF NORTHEAST AR THAT INCLUDES RANDOLPH...LAWRENCE AND
EXTREME WESTERN PORTIONS OF CLAY COUNTY. THE HRRR MODEL INDICATES
SHOWERS SPREADING INTO THIS AREA THIS MORNING. RADARS ALREADY
INDICATE SHOWERS JUST TO THE NORTHWEST GRADUALLY SLIPPING TO THE
SOUTHEAST.
JCL
&&
.DISCUSSION... /ISSUED 348 AM CDT SAT AUG 29 2015/
EARLY THIS MORNING...TEMPERATURES WERE A LITTLE WARMER THAN IN
RECENT DAYS RANGING FROM THE MIDDLE 60S TO LOWER 70S. MIDDLE AND
HIGH LEVEL CLOUDS STRETCHED FROM NORTHWEST TN AND THE MO BOOTHEEL
INTO NORTHEAST AR.
THE MIDSOUTH WILL BE AFFECTED BY TWO SYSTEMS THE NEXT COUPLE OF
DAYS...ONE AN UPPER LEVEL TROUGH APPROACHING FROM THE NORTHWEST
AND ANOTHER AN UPPER LEVEL LOW ALONG THE NORTHERN GULF COAST THAT
WILL LIFT NORTHEASTWARD. BOTH OF THESE FEATURES ARE FAIRLY WEAK.
THE LATEST GUIDANCE INDICATES HIGHER POPS ESPECIALLY FOR TONIGHT
AND SUNDAY THAN THE EARLIER GUIDANCE...DID RAISE THE POPS SOME BUT
CONFIDENCE IS NOT HIGH ENOUGH TO GO GREATER THAN 30 PERCENT POPS
ATTM. LATER FORECASTS MAY NEED TO RAISE THE POPS IN SOME LOCATIONS
DURING THIS TIMEFRAME.
FOR TODAY...AN UPPER LEVEL TROUGH FROM THE GREAT LAKES TO THE
CENTRAL PLAINS WILL MOVE SOUTHEASTWARD APPROACHING NORTHEAST AR.
INDICATED A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS FOR A SMALL
PORTION OF NORTHEAST AR TODAY. MEANWHILE...AN UPPER LEVEL LOW
WILL BE LOCATED ALONG THE MS AND AL COAST. THIS LOW WILL HELP TO
PUSH MORE MOIST AND UNSTABLE AIR INTO THE MIDSOUTH FROM THE EAST.
CONTINUED TO INDICATE A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS
FOR NORTHEAST MS AND THE TN RIVER VALLEY OF WEST TN. CLOUDS WILL
BE ON THE INCREASE ACROSS THE MIDSOUTH IN ASSOCIATION WITH BOTH OF
THESE SYSTEMS. TEMPERATURES WILL BE SEASONABLY WARM.
FOR TONIGHT...THE UPPER LEVEL TROUGH WILL PUSH INTO THE MIDSOUTH
FROM THE NORTHWEST WITH THE UPPER LOW ALONG THE CENTRAL GULF COAST
MOVING NORTHEASTWARD INTO CENTRAL AL. INDICATED A CHANCE OF
SHOWERS AND THUNDERSTORMS FOR MOST OF THE REGION.
ON SUNDAY...THE UPPER LEVEL LOW OVER CENTRAL AL WILL CONTINUE TO
PUSH NORTHEASTWARD WITH A WEAK BROAD UPPER LEVEL TROUGH OVER THE
MIDSOUTH. CONTINUED TO MENTION A CHANCE OF SHOWERS AND
THUNDERSTORMS. CLOUDS ARE EXPECTED TO DECREASE FROM THE SOUTHWEST.
MONDAY...AN UPPER LEVEL TROUGH WILL BE WEST OF THE MIDSOUTH WHILE
UPPER LEVEL RIDGING WILL BE TO THE EAST WITH WEAK SOUTHERLY FLOW
SURFACE AND ALOFT ACROSS THE REGION. THERE WILL BE ENOUGH MOISTURE
AND INSTABILITY FOR A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS.
IT WILL FEEL LIKE SUMMER WITH PLENTY OF SUNSHINE BOOSTING
TEMPERATURES TO NEAR NORMAL READINGS.
TUESDAY...THE UPPER LEVEL RIDGE IS FORECAST TO BUILD ACROSS THE
MIDSOUTH FROM THE EAST SUPPRESSING MOST CONVECTION. KEPT POPS
BELOW MENTIONABLE LEVELS.
TOWARD THE MIDDLE AND END OF NEXT WEEK...INCREASING MOISTURE IS
FORECAST TO SPREAD INTO THE REGION FROM THE SOUTHEAST AS UPPER
LEVEL RIDGING WEAKENS. THIS WILL RESULT IN A RETURN OF A SMALL
CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY. TEMPERATURES WILL
REMAIN SEASONABLY WARM TO HOT WITH NO COLD FRONTAL PASSAGES
EXPECTED.
JCL
&&
.AVIATION...
06Z TAF CYCLE
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD WITH LIGHT SSE
WINDS.
TVT
&&
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
616 AM CDT SAT AUG 29 2015
.UPDATE...
UPDATED FOR 12Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 440 AM CDT SAT AUG 29 2015/
UPDATE...
UPDATED TO INCREASE THE POPS FOR TODAY TO 40 PERCENT ACROSS
PORTIONS OF NORTHEAST AR THAT INCLUDES RANDOLPH...LAWRENCE AND
EXTREME WESTERN PORTIONS OF CLAY COUNTY. THE HRRR MODEL INDICATES
SHOWERS SPREADING INTO THIS AREA THIS MORNING. RADARS ALREADY
INDICATE SHOWERS JUST TO THE NORTHWEST GRADUALLY SLIPPING TO THE
SOUTHEAST.
JCL
DISCUSSION... /ISSUED 348 AM CDT SAT AUG 29 2015/
EARLY THIS MORNING...TEMPERATURES WERE A LITTLE WARMER THAN IN
RECENT DAYS RANGING FROM THE MIDDLE 60S TO LOWER 70S. MIDDLE AND
HIGH LEVEL CLOUDS STRETCHED FROM NORTHWEST TN AND THE MO BOOTHEEL
INTO NORTHEAST AR.
THE MIDSOUTH WILL BE AFFECTED BY TWO SYSTEMS THE NEXT COUPLE OF
DAYS...ONE AN UPPER LEVEL TROUGH APPROACHING FROM THE NORTHWEST
AND ANOTHER AN UPPER LEVEL LOW ALONG THE NORTHERN GULF COAST THAT
WILL LIFT NORTHEASTWARD. BOTH OF THESE FEATURES ARE FAIRLY WEAK.
THE LATEST GUIDANCE INDICATES HIGHER POPS ESPECIALLY FOR TONIGHT
AND SUNDAY THAN THE EARLIER GUIDANCE...DID RAISE THE POPS SOME BUT
CONFIDENCE IS NOT HIGH ENOUGH TO GO GREATER THAN 30 PERCENT POPS
ATTM. LATER FORECASTS MAY NEED TO RAISE THE POPS IN SOME LOCATIONS
DURING THIS TIMEFRAME.
FOR TODAY...AN UPPER LEVEL TROUGH FROM THE GREAT LAKES TO THE
CENTRAL PLAINS WILL MOVE SOUTHEASTWARD APPROACHING NORTHEAST AR.
INDICATED A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS FOR A SMALL
PORTION OF NORTHEAST AR TODAY. MEANWHILE...AN UPPER LEVEL LOW
WILL BE LOCATED ALONG THE MS AND AL COAST. THIS LOW WILL HELP TO
PUSH MORE MOIST AND UNSTABLE AIR INTO THE MIDSOUTH FROM THE EAST.
CONTINUED TO INDICATE A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS
FOR NORTHEAST MS AND THE TN RIVER VALLEY OF WEST TN. CLOUDS WILL
BE ON THE INCREASE ACROSS THE MIDSOUTH IN ASSOCIATION WITH BOTH OF
THESE SYSTEMS. TEMPERATURES WILL BE SEASONABLY WARM.
FOR TONIGHT...THE UPPER LEVEL TROUGH WILL PUSH INTO THE MIDSOUTH
FROM THE NORTHWEST WITH THE UPPER LOW ALONG THE CENTRAL GULF COAST
MOVING NORTHEASTWARD INTO CENTRAL AL. INDICATED A CHANCE OF
SHOWERS AND THUNDERSTORMS FOR MOST OF THE REGION.
ON SUNDAY...THE UPPER LEVEL LOW OVER CENTRAL AL WILL CONTINUE TO
PUSH NORTHEASTWARD WITH A WEAK BROAD UPPER LEVEL TROUGH OVER THE
MIDSOUTH. CONTINUED TO MENTION A CHANCE OF SHOWERS AND
THUNDERSTORMS. CLOUDS ARE EXPECTED TO DECREASE FROM THE SOUTHWEST.
MONDAY...AN UPPER LEVEL TROUGH WILL BE WEST OF THE MIDSOUTH WHILE
UPPER LEVEL RIDGING WILL BE TO THE EAST WITH WEAK SOUTHERLY FLOW
SURFACE AND ALOFT ACROSS THE REGION. THERE WILL BE ENOUGH MOISTURE
AND INSTABILITY FOR A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS.
IT WILL FEEL LIKE SUMMER WITH PLENTY OF SUNSHINE BOOSTING
TEMPERATURES TO NEAR NORMAL READINGS.
TUESDAY...THE UPPER LEVEL RIDGE IS FORECAST TO BUILD ACROSS THE
MIDSOUTH FROM THE EAST SUPPRESSING MOST CONVECTION. KEPT POPS
BELOW MENTIONABLE LEVELS.
TOWARD THE MIDDLE AND END OF NEXT WEEK...INCREASING MOISTURE IS
FORECAST TO SPREAD INTO THE REGION FROM THE SOUTHEAST AS UPPER
LEVEL RIDGING WEAKENS. THIS WILL RESULT IN A RETURN OF A SMALL
CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY. TEMPERATURES WILL
REMAIN SEASONABLY WARM TO HOT WITH NO COLD FRONTAL PASSAGES
EXPECTED.
JCL
.AVIATION...
06Z TAF CYCLE
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD WITH LIGHT SSE
WINDS.
TVT
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
440 AM CDT SAT AUG 29 2015
.UPDATE...
UPDATED TO INCREASE THE POPS FOR TODAY TO 40 PERCENT ACROSS
PORTIONS OF NORTHEAST AR THAT INCLUDES RANDOLPH...LAWRENCE AND
EXTREME WESTERN PORTIONS OF CLAY COUNTY. THE HRRR MODEL INDICATES
SHOWERS SPREADING INTO THIS AREA THIS MORNING. RADARS ALREADY
INDICATE SHOWERS JUST TO THE NORTHWEST GRADUALLY SLIPPING TO THE
SOUTHEAST.
JCL
&&
.DISCUSSION... /ISSUED 348 AM CDT SAT AUG 29 2015/
EARLY THIS MORNING...TEMPERATURES WERE A LITTLE WARMER THAN IN
RECENT DAYS RANGING FROM THE MIDDLE 60S TO LOWER 70S. MIDDLE AND
HIGH LEVEL CLOUDS STRETCHED FROM NORTHWEST TN AND THE MO BOOTHEEL
INTO NORTHEAST AR.
THE MIDSOUTH WILL BE AFFECTED BY TWO SYSTEMS THE NEXT COUPLE OF
DAYS...ONE AN UPPER LEVEL TROUGH APPROACHING FROM THE NORTHWEST
AND ANOTHER AN UPPER LEVEL LOW ALONG THE NORTHERN GULF COAST THAT
WILL LIFT NORTHEASTWARD. BOTH OF THESE FEATURES ARE FAIRLY WEAK.
THE LATEST GUIDANCE INDICATES HIGHER POPS ESPECIALLY FOR TONIGHT
AND SUNDAY THAN THE EARLIER GUIDANCE...DID RAISE THE POPS SOME BUT
CONFIDENCE IS NOT HIGH ENOUGH TO GO GREATER THAN 30 PERCENT POPS
ATTM. LATER FORECASTS MAY NEED TO RAISE THE POPS IN SOME LOCATIONS
DURING THIS TIMEFRAME.
FOR TODAY...AN UPPER LEVEL TROUGH FROM THE GREAT LAKES TO THE
CENTRAL PLAINS WILL MOVE SOUTHEASTWARD APPROACHING NORTHEAST AR.
INDICATED A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS FOR A SMALL
PORTION OF NORTHEAST AR TODAY. MEANWHILE...AN UPPER LEVEL LOW
WILL BE LOCATED ALONG THE MS AND AL COAST. THIS LOW WILL HELP TO
PUSH MORE MOIST AND UNSTABLE AIR INTO THE MIDSOUTH FROM THE EAST.
CONTINUED TO INDICATE A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS
FOR NORTHEAST MS AND THE TN RIVER VALLEY OF WEST TN. CLOUDS WILL
BE ON THE INCREASE ACROSS THE MIDSOUTH IN ASSOCIATION WITH BOTH OF
THESE SYSTEMS. TEMPERATURES WILL BE SEASONABLY WARM.
FOR TONIGHT...THE UPPER LEVEL TROUGH WILL PUSH INTO THE MIDSOUTH
FROM THE NORTHWEST WITH THE UPPER LOW ALONG THE CENTRAL GULF COAST
MOVING NORTHEASTWARD INTO CENTRAL AL. INDICATED A CHANCE OF
SHOWERS AND THUNDERSTORMS FOR MOST OF THE REGION.
ON SUNDAY...THE UPPER LEVEL LOW OVER CENTRAL AL WILL CONTINUE TO
PUSH NORTHEASTWARD WITH A WEAK BROAD UPPER LEVEL TROUGH OVER THE
MIDSOUTH. CONTINUED TO MENTION A CHANCE OF SHOWERS AND
THUNDERSTORMS. CLOUDS ARE EXPECTED TO DECREASE FROM THE SOUTHWEST.
MONDAY...AN UPPER LEVEL TROUGH WILL BE WEST OF THE MIDSOUTH WHILE
UPPER LEVEL RIDGING WILL BE TO THE EAST WITH WEAK SOUTHERLY FLOW
SURFACE AND ALOFT ACROSS THE REGION. THERE WILL BE ENOUGH MOISTURE
AND INSTABILITY FOR A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS.
IT WILL FEEL LIKE SUMMER WITH PLENTY OF SUNSHINE BOOSTING
TEMPERATURES TO NEAR NORMAL READINGS.
TUESDAY...THE UPPER LEVEL RIDGE IS FORECAST TO BUILD ACROSS THE
MIDSOUTH FROM THE EAST SUPPRESSING MOST CONVECTION. KEPT POPS
BELOW MENTIONABLE LEVELS.
TOWARD THE MIDDLE AND END OF NEXT WEEK...INCREASING MOISTURE IS
FORECAST TO SPREAD INTO THE REGION FROM THE SOUTHEAST AS UPPER
LEVEL RIDGING WEAKENS. THIS WILL RESULT IN A RETURN OF A SMALL
CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY. TEMPERATURES WILL
REMAIN SEASONABLY WARM TO HOT WITH NO COLD FRONTAL PASSAGES
EXPECTED.
JCL
&&
.AVIATION...
06Z TAF CYCLE
VFR. PATCHY FOG POSSIBLE AT KMKL. SSE WINDS 3-7 KTS.
30
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
316 PM CDT SAT AUG 29 2015
.SHORT TERM...
TONIGHT - CONFIDENCE...MEDIUM
MID LEVEL TROUGH AXIS SHIFTING SOUTHEAST OF WI. MEANWHILE THE LOW
LEVELS REMAIN MOIST WITH LITTLE STIRRING OR CHANGE OF AIRMASS. A
WEAK INVERTED TROUGH EXTENDS INTO WI. WIDESPREAD STRATUS HAS A
PRETTY FIRM GRIP ON CENTRAL AND SOUTHERN WI. SOME BREAKS AND THIN
SPOTS HAVE TRIED TO TAKE SHAPE WITHIN SUBSIDENCE REGION OF EXITING
SHORTWAVE HOWEVER THIS HAS BEEN SLOW TO EVOLVE WITH OVC CONDITIONS
BEING PREVALENT. EXPECTING THIS REGIME TO CHANGE LITTLE INTO THE
OVERNIGHT HOURS AS THE COLUMN REMAINS FREE OF WIND IN THE SURFACE-
850 MILLIBAR LAYER. EXPECT FOG TO BECOME A BIT THICKER AS THE NIGHT
WEARS ON BUT CONFIDENCE NOT GREAT THAT WIDESPREAD DENSE FOG WILL
BECOME AN ISSUE DUE TO THE ONGOING STRATUS FIELD. ANY BREAKS THAT
EVOLVE WOULD EXPECT STRATUS/FOG TO FILL RIGHT BACK IN. WITH THE
CLOUD COVER LITTLE TEMP DROPOFF EXPECTED.
.SUNDAY - CONFIDENCE...MEDIUM
MID LEVEL RIDGING TAKES HOLD WITH SURFACE HIGH DOMINATING IN THE LOW
LEVELS. AGAIN NOT MUCH STIRRING SO EROSION OF MORNING FOG/STRATUS MAY
BE A SLOW PROCESS. 925 THERMAL TROUGH EASES A BIT WITH WINDS TURNING
MORE SW AND 850 SHOWS SOME WARMING AS WELL. SO ONCE THE SUN BREAKS
THROUGH EXPECT TEMPS TO GET BACK INTO THE 70S WITH PERHAPS AN 80 OR
TWO IN WESTERN CWA WHERE LINGERING STRATUS LIKELY TO ERODE SOONEST.
SUNDAY NIGHT THROUGH TUESDAY...FORECAST CONFIDENCE HIGH.
THE UPPER RIDGE OVER THE PLAINS WILL ROLL OVER INTO THE GREAT
LAKES FOR SUN NT AND MON. THE SFC HIGH WILL MOVE SLIGHTLY TO THE
EAST OF THE REGION WITH A SLY FLOW DEVELOPING. 925 MB TEMPS WILL
RISE TO 23-24C BY LATE AFTERNOON ON MON WHICH YIELDS HIGHS IN THE
MID TO UPPER 80S AWAY FROM THE LAKE BREEZE. THE UPPER RIDGE WILL
FLATTEN AND MOVE TO THE MID ATLANTIC STATES FOR TUE WITH A SWLY
FLOW ALOFT FROM THE WRN USA INTO THE NRN GREAT LAKES. IT APPEARS
ANY EMBEDDED WEAK SHORTWAVE TROUGHS WILL REMAIN TO THE WEST SO THE
DRY FCST CONTINUES. HIGH TEMPS MID TO UPPER 80S WILL CONTINUE
EXCEPT NEAR LAKE MI.
.LONG TERM...WEDNESDAY THROUGH SATURDAY...FORECAST CONFIDENCE
MEDIUM.
THE MEAN UPPER TROUGH WILL REMAIN OVER WRN CANADA AND THE PACIFIC
NW WITH A BROAD RIDGE OVER MUCH OF THE CENTRAL AND ERN USA. WEAK
SHORTWAVE TROUGHS HOWEVER WILL FLATTEN THE RIDGE AT TIMES AND
BRING SLIGHT CHANCES OF TSTORMS TO THE REGION FROM WED-SAT. VERY
WARM AND HUMID CONDITIONS WILL CONTINUE.
&&
.AVIATION/00Z TAFS/...VERY WEAK 925/850 FLOW THROUGH TONIGHT AND
INTO EARLY SUNDAY AS WELL. SUBSIDENCE WITH PASSING SHORTWAVE NOT
DOING MUCH TO ERODE THE CLOUD COVER. RAP SOUNDINGS LOOK TO DRY
THINGS OUT LATER TODAY AND THIS EVENING BUT THAT CONTINUES TO LOOK
OPTIMISTIC. LEANING MORE TOWARDS THE METMOS GUID GIVEN PRESENT VSBL
IMAGERY/SFC OBS. STRATUS LIKELY TO KEEP VSBYS FROM GETTING
WIDESPREAD DENSE THOUGH LOW LEVELS ARE MORE MOIST DUE TO THE RECENT
RAINS. BUT STILL EXPECTING A GOOD DEAL OF LIFR CONDITIONS. THE
WIDESPREAD STRATUS/FOG IS LIKELY TO PERSIST INTO SUNDAY MORNING.
THEN AS SOME WEAK WAA TAKES HOLD EXPECTING SOME EROSION TO TAKE
PLACE WITH GRADUALLY IMPROVING CIGS/VSBYS AS THE DAY WEARS ON.
&&
.MARINE...WITH A LIGHT WIND REGIME AND A MOIST AIRMASS REMAINING IN
PLACE HAVE HOISTED A DENSE FOG ADVISORY UNTIL 10 AM SUNDAY. FOG
WILL BE REMAIN POSSIBLE AT TIMES OVER LAKE MI FOR THE NEW WEEK
DUE TO A HUMID AND STAGNANT AIRMASS.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...DENSE FOG ADVISORY UNTIL 10 AM CDT SUNDAY FOR LMZ643>646.
&&
$$
TONIGHT/SUNDAY AND AVIATION/MARINE...COLLAR
SUNDAY NIGHT THROUGH SATURDAY...GEHRING
AREA FORECAST DISCUSSION
NWS TUCSON AZ
905 PM MST SUN AUG 30 2015
.SYNOPSIS...ANOTHER GOOD CHANCE OF SHOWERS AND THUNDERSTORMS ON
MONDAY. A SLOW DRYING TREND WILL THEN LIMIT THUNDERSTORMS TO EAST OF
TUCSON THE SECOND HALF OF THE WEEK. HOTTER THAN AVERAGE TEMPERATURES
WILL FALL TO NEAR AVERAGE AROUND THE MIDDLE OF THE WEEK.
&&
.DISCUSSION...WIDELY SCATTERED SHOWERS AND THUNDERSTORMS THIS
AFTERNOON INTO THE EARLY EVENING HOURS. OUTFLOW FROM STORMS IN
CENTRAL PIMA COUNTY SENT NW-N INTO MARICOPA COUNTY ALONG COMBINED
WITH WEAK UPPER LEVEL DYNAMICS TO GENERATE NEW THUNDERSTORMS IN
MARICOPA COUNTY WITHIN IN PAST 1-2 HRS. MOST OF THIS ACTIVITY IS
SLOWLY MOVING TO THE EAST. NEW 00Z RUN OF THE UOFA WRF NAM ALONG
WITH 02Z HRRR RUN MOVES THIS AREA OF SHOWERS/STORMS ACROSS SE PINAL
COUNTY AND THE NORTHERN PARTS OF THE TUCSON METRO AREA BEFORE
DIMINISHING AFTER MIDNIGHT. RAN OUT A QUICK UPDATE TO THE FORECAST
LAST HOUR TO ACCOUNT FOR THIS THINKING. OTHERWISE MOST OF THE
FORECAST AREA WILL REMAIN DRY DURING THE OVERNIGHT HOURS.
EASTERN HALF OF THE FORECAST AREA WILL BE THE FOCUS OF STORMS MONDAY
AFTERNOON AND EVENING.
&&
.AVIATION...VALID THRU 01/00Z.
WDLY SCTD -SHRA/ISOLD TS N-NW OF KTUS THRU 31/10Z...OTRW DECREASING
DEBRIS CLOUDS THRU 31/16Z. AFT 31/18Z SCTD SHRA/TSRA DVLPG. BRIEF
MVFR CONDS AND GUSTY WINDS TO 45 KTS WILL BE PSBL IN AND AROUND THE
STRONGER STORMS. OUTSIDE OF THUNDERSTORM INFLUENCE SURFACE WINDS
WILL GENERALLY BE UNDER 10 KTS. AVIATION DISCUSSION NOT UPDATED FOR
TAF AMENDMENTS.
&&
.FIRE WEATHER...ISOLATED SHOWERS MAINLY NW OF TUCSON INTO EARLY
MONDAY MORNING. ON MONDAY THUNDERSTORMS WILL TEND TO BE MORE FOCUSED
OVER EASTERN ZONES...WITH DIMINISHED THUNDERSTORM ACTIVITY FROM
WEDNESDAY ON. THUNDERSTORMS ARE EXPECTED TO BE WET AND AS IS TYPICAL
MAY PRODUCE STRONG...GUSTY AND ERRATIC WINDS WITH THE STRONGER
THUNDERSTORMS. OUTSIDE OF THUNDERSTORMS GENERALLY LIGHT TERRAIN
DRIVEN WINDS ARE EXPECTED. BEGINNING MONDAY A WEST TO SOUTHWEST FLOW
WILL DEVELOP ACROSS ARIZONA. THE STRONGEST WINDS WILL BE ACROSS ZONE
150...PEAKING IN THE 15-20 MPH RANGE.
&&
.CLIMATE...RECORD SETTING DAY FOR TUCSON AIRPORT AS IT RECORDED THE
82ND CONSECUTIVE DAY IN WHICH THE LOW TEMPERATURE WAS 70 DEGREES OR
WARMER. THE PREVIOUS RECORD WAS 81 DAYS WHICH OCCURRED JUST TWO
YEARS AGO. UNLESS THE AIRPORT GETS HIT WITH A STRONG THUNDERSTORM
THIS RECORD WILL LIKELY CONTINUE TO ADD UP DAYS INTO NEXT WEEKEND.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS LINCOLN IL
317 AM CDT MON AUG 31 2015
.SHORT TERM...(TODAY)
ISSUED AT 317 AM CDT MON AUG 31 2015
08Z/3AM SURFACE ANALYSIS SHOWS DISSIPATING FRONTAL BOUNDARY
EXTENDING FROM NORTHERN INDIANA INTO CENTRAL ILLINOIS...GENERALLY
ALONG A FORT WAYNE TO QUINCY LINE. AS WAS THE CASE LAST
NIGHT...QUITE A BIT OF FOG IS DEVELOPING ALONG/NORTH OF THE BOUNDARY
WHERE WINDS ARE NEARLY CALM AND LOW-LEVEL MOISTURE IS ABUNDANT.
LATEST OBS SHOW LOWEST VISBYS CONCENTRATED ALONG THE SOUTHERN SHORE
OF LAKE MICHIGAN ACROSS NORTHERN INDIANA INTO THE CHICAGO AREA.
HRRR HAS BEEN CONSISTENTLY SPREADING THIS THICKER FOG W/SW ALONG THE
FRONT INTO THE NORTHERN KILX CWA OVER THE NEXT COUPLE HOURS...AND AM
BEGINNING TO SEE THIS UNFOLDING WITH VISBY NOW DOWN TO 1/4SM AS FAR
SW AS KIKK. FOLLOWING THE HRRR TREND...WILL MENTION AREAS OF DENSE
FOG ALONG/NORTHEAST OF A GALESBURG TO BLOOMINGTON-NORMAL LINE EARLY
THIS MORNING...WITH PATCHY/AREAS OF FOG ELSEWHERE AROUND THE AREA.
HIGH-RES MODELS SUCH AS THE HRRR AND RAPID REFRESH ARE SUGGESTING
THAT ISOLATED CONVECTION MAY DEVELOP ACROSS SOUTHEAST ILLINOIS OVER
THE NEXT COUPLE OF HOURS. LATEST RADAR IMAGERY IS CLEAR...HOWEVER
SCATTERED MID-LEVEL CLOUDS ARE BEGINNING TO DEVELOP ON IR SATELLITE
IMAGERY ALONG/SOUTH OF I-70...SO HAVE OPTED TO CARRY SLIGHT CHANCE
POPS HERE EARLY THIS MORNING. LATEST WATER VAPOR IMAGERY SHOWS A
SMALL BUT VIGOROUS SHORT-WAVE DROPPING SOUTHWESTWARD FROM NORTHEAST
INDIANA. THIS FEATURE WILL LIKELY INTERACT WITH THE DECAYING FRONT
TO TRIGGER ISOLATED CONVECTION FURTHER NORTH INTO THE CWA THIS
AFTERNOON. MOST MODELS ARE HINTING AT LEAST SOME QPF ACROSS THE
SOUTHERN TWO-THIRDS OF THE AREA...SO HAVE ADDED SLIGHT CHANCE POPS
ALONG/SOUTH OF A JACKSONVILLE TO BLOOMINGTON-NORMAL LINE FOR THE
AFTERNOON.
&&
.LONG TERM...(TONIGHT THROUGH SUNDAY)
ISSUED AT 317 AM CDT MON AUG 31 2015
MAIN WEATHER STORY THROUGH THE EXTENDED WILL BE THE VERY WARM AND
HUMID CONDITIONS THAT ARE EXPECTED TO PERSIST THROUGH EARLY NEXT
WEEK. HIGH TEMPERATURES ON TUESDAY WILL REACH THE UPPER 80S TO
AROUND 90 DEGREES...THEN READINGS WILL CLIMB INTO THE LOWER 90S FOR
THE REMAINDER OF THE PERIOD. DRY WEATHER WILL GENERALLY BE THE
RULE...HOWEVER ISOLATED CONVECTION CANNOT BE RULED OUT...ESPECIALLY
TUESDAY AFTERNOON AS A WEAKNESS IN THE MEAN 500MB RIDGE AXIS REMAINS
IN THE VICINITY. MODELS ARE HINTING AT SOME QPF ACROSS THE E/NE CWA
AS THIS FEATURE GRADUALLY SHIFTS INTO THE GREAT LAKES BY WEDNESDAY.
THE NEXT SIGNIFICANT CHANCE FOR RAIN WILL NOT ARRIVE UNTIL EARLY
NEXT WEEK...WHEN A STRONG SHORT-WAVE FLATTENS THE UPPER RIDGE AND
PUSHES A COLD FRONT INTO THE REGION. MODELS ARE IN DISAGREEMENT
CONCERNING THE SPEED OF THIS PROCESS...WITH THE GFS BEING ABOUT 24
HOURS FASTER THAN THE ECMWF/GEM. THE 00Z AUG 31 GFS SHOWS THE COLD
FRONT PASSING THROUGH CENTRAL ILLINOIS LATE SUNDAY NIGHT INTO
MONDAY...WHILE THE ECMWF/GEM HAVE DELAYED FROPA UNTIL LATE MONDAY
NIGHT INTO TUESDAY. GIVEN PERSISTENT AND HIGHLY AMPLIFIED RIDGE
POSITIONED ACROSS THE MIDWEST...THINK A SLOWER BREAK DOWN TO THE
PATTERN IS PRUDENT. HAVE THEREFORE TRENDED THE FORECAST TOWARD THE
SLOWER ECMWF/GEM CONSENSUS. AS A RESULT...AM EXPECTING DRY
CONDITIONS THROUGH SUNDAY NIGHT...WITH HIGHER RAIN CHANCES ARRIVING
BY LATE MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1153 PM CDT SUN AUG 30 2015
FOG AND LOW CLOUD FORMATION LATER TONIGHT REMAIN THE PRIMARY
CONCERNS. THE STALLED OUT FRONTAL BOUNDARY ACROSS CENTRAL IL IS
BEGINNING TO WASH OUT, BUT RESIDUAL MOISTURE IN THE BOUNDARY LAYER
HAS ALLOWED DEWPOINTS TO LINGER IN THE UPPER 60S TO LOW 70S
THROUGH THE EVENING. THE POTENTIAL FOR MVFR FOG IS HIGH IN A
MAJORITY OF THE AREA OVERNIGHT. HRRR/RAP OUTPUT ARE POINTING
TOWARD THE POTENTIAL OF LOCALIZED VLIFR FOG NEAR PIA AND BMI, AND
TO SOME EXTENT SPI AND DEC. THE NAM FORECAST SOUNDINGS SHOW AT
LEAST AN MVFR CLOUD LAYER WILL DEVELOP LATER TONIGHT AT MOST TAF
LOCATIONS. HAVE INCLUDED LIFR FOG AT PIA AND BMI WITH VLIFR CIGS
AT BMI. WILL CONTINUE WITH ONLY IFR FOG LATER TONIGHT FOR SPI, DEC
AND CMI, FOR NOW.
FOG SHOULD DISSIPATE BY MID MORNING, WITH MVFR CLOUDS POSSIBLY
LINGERING TO AROUND 17-18Z. VFR CONDITIONS SHOULD DEVELOP AT ALL
TAF SITES FOR THE AFTERNOON AND THROUGH THE EVENING.
WINDS WILL REMAIN LIGHT AND VARIABLE THE REST OF THE NIGHT, WITH
A PREVAILING S-SW WIND DEVELOPING AFTER SUNRISE TOMORROW. WIND
SPEEDS DURING PEAK MIXING TOMORROW SHOULD REMAIN 10KT OR LESS.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BARNES
LONG TERM...BARNES
AVIATION...SHIMON
AREA FORECAST DISCUSSION
NWS DES MOINES IA
320 AM CDT MON AUG 31 2015
.SHORT TERM /TODAY/...
ISSUED AT 320 AM CDT MON AUG 31 2015
MUCH LIKE YESTERDAY...THE MAIN CONCERNS ARE TEMP AND VISIBILITY
TRENDS. STRATUS COVERAGE IS LESS THAN LAST NIGHT WITH ONLY SOME
TOKEN CIRRUS NW. THIS WOULD SUGGEST A MORE UNIFORM RADIATION FOG
DEVELOPMENT BUT THAT HAS NOT BEEN THE CASE WITH VISIBILITIES
SOMEWHAT VARIABLE. EVEN THOUGH SRN IA WAS HIT HARDEST WITH DENSE FOG
LAST NIGHT AND CONDITIONS ARE SIMILAR...VISIBILITIES HAVE NOT REALLY
DROPPED MUCH IN THE ADVISORY AREA. RAP 1000-950MB RH IS ACTUALLY
RELATIVELY LOWER IN THIS AREA SO ADVISORY CONFIDENCE IS NOT GREAT.
HOWEVER CONFIDENCE IS EQUALLY NOT GREAT THAT CONDITIONS WILL NOT
TANK IN THE NEXT SEVERAL HOURS EITHER SO WILL LEAVE HEADLINE AS IS
AND EVALUATE HOURLY FOR NEEDED CHANGES. LOWEST VISIBILITIES ARE
ACTUALLY NORTH SO WILL GO WITH KEEPING HEADLINE AND SPS OTHER AREAS
FOR NOW.
TEMPS WILL BE PROBLEMATIC ONCE AGAIN. MODEL SOUNDINGS ARE SOMEWHAT
MORE AGGRESSIVE WITH MIXING POTENTIAL...WHICH MAKES SOME SENSE WITH
WINDS A TAD HIGHER AND LESS STRATUS AROUND. HOWEVER IS HAS BEEN
DIFFICULT WARMING TOO MUCH OVER THE PAST FEW WEEKS...ESPECIALLY TO
GFS EXPECTATIONS WHICH HAS SHOWN AND WARM BIAS. COOLER NAM MOS HAS
BEEN BETTER RECENTLY AND WILL CONTINUE TO FOLLOW THAT LEAD. THIS
RESULTS IN TRIMMING PREVIOUS FORECAST SEVERAL DEGREES.
.LONG TERM /TONIGHT THROUGH SUNDAY/...
ISSUED AT 320 AM CDT MON AUG 31 2015
THE FORECAST FOR THIS WEEK REMAINS WARM AND MOSTLY DRY. A DEEP
LAYER RIDGE BLANKETING THE SOUTHERN U.S. WILL GRADUALLY PIVOT
AROUND OVER THE EASTERN U.S. AS A LONGWAVE TROUGH STEADILY DIGS
DOWN THE WEST COAST. THIS WILL PLACE IOWA BENEATH THE PROVERBIAL
RING OF FIRE FOR SEVERAL DAYS THIS WEEK...HOWEVER...THE SUBTLE
SHORTWAVES MOVING THROUGH THE STEERING FLOW ALOFT WILL BE FAIRLY
WEAK AND DIFFICULT TO PIN DOWN IN TERMS OF TIMING. WILL MAINTAIN
LOW 20 TO 30 POPS AT TIMES DURING THE WORK WEEK...MAINLY ACROSS
THE NORTHWEST HALF OF THE FORECAST AREA...BUT ANY STORMS SHOULD BE
OF LITTLE IMPACT. MEANWHILE TEMPERATURES WILL CLIMB WELL INTO THE
80S EACH DAY GIVEN THE WARM TEMPERATURES ALOFT...MODEST SOUTH TO
SOUTHWEST LOW LEVEL FLOW...AND MOSTLY SUNNY SKIES FORECAST.
LATER IN THE WEEK...FROM ABOUT THURSDAY THROUGH SATURDAY...THE
DEEPENING WESTERN TROUGH WILL SHUNT THE LARGE SOUTHERN RIDGE OVER
TOWARD THE APPALACHIANS AND RESULT IN ANY SUBTLE SHORTWAVES
EJECTING OUT OF THE TROUGH MOVING MORE NORTHEASTWARD ACROSS THE
HIGH PLAINS AND MINNESOTA. THIS RESULTS IN A PERIOD OF LOWER POPS
BUT SLIGHTLY HIGHER TEMPERATURES AS ANY STORMS THAT FORM SHOULD
RANGE FROM NEBRASKA UP ACROSS THE DAKOTAS AND THE WARM AIRMASS TO
OUR SOUTHEAST WILL ENCROACH A BIT MORE INTO IOWA BY THE END OF THE
WEEK. THE WEST COAST TROUGH WILL EVENTUALLY KICK OUT ACROSS THE
CENTRAL U.S. AND PUSH A COLD FRONT ACROSS OUR REGION...GENERATING
MORE WIDESPREAD SHOWERS AND THUNDERSTORMS FOLLOWED BY COOLER
WEATHER. HOWEVER...THERE CONTINUES TO BE A CONSIDERABLE AMOUNT OF
SPREAD AMONG THE LONG RANGE MODELS IN THEIR SOLUTIONS FOR THIS
EVOLUTION AND PARTICULARLY THE TIMING OF RAIN AND FRONTAL PASSAGE
FOR IOWA. HAVE THUS STUCK CLOSE TO MODEL CONSENSUS WITH RAIN
CHANCES MOSTLY IN THE SUNDAY/SUNDAY NIGHT TIME FRAMES AND COOLER
WEATHER LIKELY BY NEXT MONDAY. THESE DETAILS WILL GRADUALLY COME
INTO FOCUS LATER THIS WEEK.
&&
.AVIATION...31/06Z
ISSUED AT 1144 PM CDT SUN AUG 30 2015
MAIN CONCERN WILL BE FOG AND STRATUS POTENTIAL. EXPECT AT LEAST MVFR
CONDITIONS OVERNIGHT...WITH MANY LOCATIONS IFR OR LOWER. KFOD AND
KMCW WILL SEE THE LOWER VSBYS INITIALLY...WITH LOWER VSBYS MIGRATING
SOUTHEASTWARD TOWARD THE KOTM AND POSSIBLY KDSM TERMINALS. CLOUDS
MOVING IN FROM THE WEST MAY MITIGATE THE LOWER VSBYS ACROSS WESTERN
IA. DURING THE DAY ON MONDAY...VFR FLIGHT RULES EXPECTED.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 8 AM CDT THIS MORNING FOR APPANOOSE-
CLARKE-DAVIS-DECATUR-JASPER-LUCAS-MAHASKA-MARION-MONROE-
POWESHIEK-TAMA-WAPELLO-WARREN-WAYNE.
&&
$$
SHORT TERM...SMALL
LONG TERM...LEE
AVIATION...ZOGG
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1150 PM CDT SUN AUG 30 2015
.UPDATE...
ISSUED AT 720 PM CDT SUN AUG 30 2015
HAVE GONE OUT WITH A DENSE FOG ADVISORY FOR MOST OF EASTERN IA AND
ADJACENT IL COUNTIES ALONG I-80 FOR LATE TONIGHT THROUGH EARLY
MORNING MONDAY. CONDITIONS ARE SIMILAR TO LAST NIGHT...WITH THE
SAME AIRMASS IN PLACE AND NEARLY CALM WINDS UNDER THE W-E SURFACE
RIDGE OVERHEAD. SURFACE DEWPOINTS ARE HIGHER IN MANY PLACES THAN
LAST NIGHT AT THIS TIME. CROSSOVER TECHNIQUE...USING DEWPOINTS AT
PEAK HEATING AND CURRENT FORECAST LOWS SUPPORTS WIDESPREAD FOG.
THE FOG COULD BE A LITTLE LATER TO DEVELOP DUE TO THE HIGHER
TEMPERATURES AND TEMP/DEWPOINT DEPARTURES AT THIS TIME TONIGHT VS
THIS TIME LAST NIGHT.
&&
.SYNOPSIS...
ISSUED AT 333 PM CDT SUN AUG 30 2015
SURFACE RIDGE AXIS EXTENDS FROM THE GREAT LAKES THROUGH THE CWA
AND INTO THE SOUTH CENTRAL PLAINS AT MID AFTN. THE FAIRLY
WIDESPREAD DENSE FOG BURNED OFF BY MID TO LATE AM LEAVING BEHIND
FAIRLY EXTENSIVE STRATUS WHICH HAS BEEN STEADILY ERODING FROM THE
SOUTH AND EVOLVING INTO SCATTERED STRATOCU DECK. THE INCREASING
PEAKS OF SUNSHINE HAS HELPED TO BUMP TEMPS UP TO NEAR LATE
AUGUST NORMALS WITH MANY AREAS IN THE UPPER 70S TO LOWER 80S.
THE EXCEPTION BEING MAINLY PORTIONS OF NORTHEAST IA WHERE STRATUS
SILL LINGERS AND AIDING IN HOLDING TEMPS DOWN IN THE LOWER 70S
ATTIM... BUT WITH MORE LATE DAY SUNSHINE SHOULD SEE TEMPS IN THESE
AREAS SURGE LATE. PATTERN ALOFT FEATURES AN AMPLIFIED RIDGE /HEAT DOME/
THROUGH THE PLAINS IN ADVANCE OF A PACIFIC NORTHWEST TROUGH. THE NEXT
24 HOURS WILL SEE THIS RIDGE AND WARMER AIR BUILD INTO THE MID-
MISSISSIPPI VLY AS THE PACIFIC NORTHWEST TROUGH SHIFTS ACROSS THE
NORTHERN ROCKIES. THIS WILL RESULT IN CONTINUATION OF DRY CONDITIONS
WITH WARMER TEMPS ON MONDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 333 PM CDT SUN AUG 30 2015
MAIN CHALLENGE REMAINS LOW CLOUDS AND FOG POTENTIAL WITH IMPACT ON
TEMPS.
FOLLOWING TRENDS PER SATL AND OBS FROM LATE AFTN WITH DECREASING STRATUS
NORTHWEST CWA EVOLVING INTO SCATTERED STRATOCUMULUS THEN MOSTLY
CLEAR FOR A TIME THIS EVENING. LATE EVENING AND OVERNIGHT WITH
CONTINUED WEAK WINDS AND ABUNDANT LOW LEVEL MOISTURE EXPECT
REDEVELOPMENT OF FOG DENSE IN SOME AREAS... WITH ALSO SOME STRATUS
POSSIBLE ALTHOUGH UNCERTAIN ON EXTENT OF ANY STRATUS FORMATION WITH
LATEST RAP AND NAM MODELS SHOWING AROUND 15+ KTS OF WIND JUST ABOVE
MOIST LAYER WHICH MAY BE SUFFICIENT MIXING TO OFFSET WIDESPREAD STRATUS
FORMATION AND WITH JUST DIURNAL CUMULUS ACROSS MO DON/T EXPECT ANY
ADVECTION OF LOW DECK. MIN TEMPS WILL BE CHALLENGING AND DEPENDENT ON
FOG AND STRATUS TRENDS. AS WE SAW THIS AM... POTENTIAL FOR AREAS THAT
STAY CLEAR LONGER TO RADIATE DOWN INTO THE 50S WITH NEAR CALM WINDS.
OTHERWISE... WITH TEMPS A BIT WARMER TODAY FOR MANY AND WITH MID AFTN
DEWPTS IN MID/UPPER 60S I HAVE KEPT LOWS MAINLY IN RANGE OF 60-67 DEGS.
ON MONDAY...ANY FOG SHOULD BURN OFF A BIT EARLIER TOMORROW BY MID AM
WITH A BIT STRONGER SOUTHERLY WIND DEVELOPING OF 5-10 KTS. ANY
STRATUS SHOULD LIFT TO FAIR WX CUMULUS DURING AFTERNOON AND GENERALLY
MOSTLY SUNNY SKIES. THIS WILL ALLOW TEMPS TO CLIMB WELL INTO THE 80S
WITH WIDESPREAD MID TO A FEW UPPER 80S. THESE TEMPS COUPLED WITH
DEWPTS WELL IN THE 60S TO NEAR 70 DEGS WILL MAKE FOR VERY WARM FEEL
WITH HEAT INDICES AROUND 90/L90S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 333 PM CDT SUN AUG 30 2015
OVERVIEW...BUILDING AND PERSISTENT UPPER-LEVEL RIDGE OVER THE
CENTRAL U.S. WILL LEAD TO ABOVE AVERAGE TEMPERATURES AND HUMID
CONDITIONS THROUGH THE EXTENDED PERIOD. OVERALL CHANCES FOR RAIN
ARE VERY LOW.
TUESDAY AND WEDNESDAY...1000-500MB THICKNESS VALUES ARE FORECAST TO
BE NEAR 576-579 DAM WITH 850MB TEMPS IN THE UPPER TEENS/NEAR 20 C.
FORECAST HIGHS ARE IN THE UPPER 80S TO NEAR 90 F...WITH HEAT INDICES
IN THE LOWER TO MIDDLE 90S.
A SHORTWAVE TROUGH FROM REMNANT MONSOONAL CONVECTION MAY TRAVERSE
THE MIDWEST ON WEDNESDAY BUT MODELS TRACK IT NW OF E IOWA/W
ILLINOIS. CONSEQUENTLY KEPT THE FORECAST DRY.
THURSDAY THROUGH SATURDAY...RAW MODELS STILL APPEAR TO HAVE A WARM
BIAS AND ARE PROJECTING LOWER TO MIDDLE 90S. HUMID
CONDITIONS...850MB TEMPS IN THE UPPER TEENS TO POSSIBLY LOWER 20S
CELSIUS...AND A LOWER SEPTEMBER SUN ANGLE BACK A TEMP FORECAST
SLIGHTLY BELOW THE HIGHER RAW MODEL DATA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1150 PM CDT SUN AUG 30 2015
PATCHY FOG WILL BECOME MORE WIDESPREAD AND DENSE DUE TO LIGHT
WINDS AND LINGERING LOW LEVEL MOISTURE IN A WEAK FLOW REGIME OVER
THE REGION. FORECASTS ARE TRENDED WITH A HIGH CONFIDENCE
TRANSITION TO IFR BY 08Z WITH A POTENTIAL FOR LIFR TO VLIFR DUE TO
BOTH REDUCED VISIBILITIES AND DEVELOPING LOW CIGS AND VERTICAL
VISIBILITIES FROM 08Z THROUGH ROUGHLY 13Z. AN IMPROVEMENT TREND
FOLLOWS THROUGH ROUGHLY 15Z...WITH HIGH CONFIDENCE THAT ALL SITES
SHOULD BE AT LEAST MVFR BY NOON AND THEN VFR BY AFTERNOON AS FOG
DISSIPATES AND CIGS LIFT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...DENSE FOG ADVISORY UNTIL 8 AM CDT MONDAY FOR BENTON-CEDAR-
CLINTON-DES MOINES-HENRY IA-IOWA-JACKSON-JEFFERSON-JOHNSON-
JONES-KEOKUK-LEE-LINN-LOUISA-MUSCATINE-SCOTT-VAN BUREN-
WASHINGTON.
IL...DENSE FOG ADVISORY UNTIL 8 AM CDT MONDAY FOR HENDERSON-HENRY IL-
MERCER-ROCK ISLAND-WHITESIDE.
MO...NONE.
&&
$$
UPDATE...SHEETS
SYNOPSIS...MCCLURE
SHORT TERM...MCCLURE
LONG TERM...UTTECH
AVIATION...SHEETS
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
1204 AM CDT MON AUG 31 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 400 PM CDT SUN AUG 30 2015
WATER VAPOR IMAGERY ALONG WITH RAP H5 HEIGHT ANALYSIS SHOWS UPPER
RIDGING BUILDING IN THIS AFTERNOON. A TROUGH EJECTING ACROSS THE
NRN ROCKIES HAS ALLOWED A BROAD AREA OF SFC LOW PRESSURE TO FORM
ACROSS ERN MT/NRN NODAK/SRN CANADA. IT IS THIS LOW THAT HAS
RESULTED IN AN INCREASING PRESSURE GRADIENT AND THE STRONGER SOUTH
WINDS WE HAVE SEEN TODAY.
IT IS THESE SOUTH WINDS THAT MAKE THE FORECAST FOR TONIGHT TRICKY.
NAM BUFR SOUNDINGS MONDAY MORNING LOOK LIKE CARBON COPIES OF THE MPX
SOUNDING THIS MORNING...WHICH OF COURSE WAS ASSOCIATED WITH ANOTHER
ROUND OF LOW STRATUS. STRATUS IS STILL HANGING TOUGH IN IOWA AND
WITH THE PATTERN TO OUR SOUTHEAST NOT MUCH DIFFERENT FROM WHAT WE
HAVE SEEN THE PAST COUPLE OF NIGHTS...EXPECT STRATUS TO EXPAND AGAIN
TONIGHT...THE QUESTION IS JUST HOW FAR NW DOES IT COME. ONE BIG
DIFFERENCE BETWEEN TODAY AND THE PAST COUPLE OF DAYS IS WE HAVE
STRONGER WINDS AND BETTER BOUNDARY LAYER MIXING TODAY. THE GRADIENT
AND ASSOCIATED WINDS WILL REMAIN IN PLACE THROUGH THE NIGHT...ADDING
A LAYER OF UNCERTAINTY TO THE SKY FORECAST. FOR NOW...DID A SOFT
PLAY FOR THE STRATUS...WITH 40/50% COVERAGE FROM SOUTH CENTRAL MN
INTO EAST CENTRAL MN AND WRN WI LATE TONIGHT/EARLY MONDAY MORNING
AND WILL LET FUTURE SHIFTS UP SKY COVER IF NEED BE WHEN THERE IS A
BETTER HANDLE ON WHERE IT IS GOING.
FOR MONDAY...THE PREVIOUSLY MENTIONED LOW WELL SEND A FRONT ACROSS
THE DAKOTAS...APPROACHING WEST CENTRAL MN BY THE AFTERNOON.
HOWEVER...WE ARE NOT ANTICIPATING ANY ACTIVITY ALONG THE FRONT THIS
FAR SOUTH...SO WE REMOVED WHAT SMALL POPS WERE MENTION MONDAY
AFTERNOON IN OUR NW. BESIDE NONE OF THE HI-RES...DETERMINISTIC...OR
ENSEMBLE MODELS SHOWING ANY PRECIP IN OUR AREA...FORECAST SOUNDINGS
AT AXN AND SURROUNDING SITES SHOW A STRONG WARM NOSE BETWEEN H8 AND
H7 THAT LOOKS TO KEEP A LID ON DEEP MOIST CONVECTION THIS FAR SOUTH.
IN ADDITION...THE WAVE AND ASSOCIATED HEIGHT FALLS DRIVING THIS
FRONT ARE GOING FROM MT TO HUDSON BAY...STAYING WELL NW OF THE
MPX AREA...SO FEEL CONFIDENT IN THE DRY FORECAST FOR MONDAY.
BESIDE DRY...ALL OF THE MODELS SHOW 925-850 TEMPS IN WRN MN DROPPING
A COUPLE OF DEGS C MONDAY AFTERNOON COMPARED TO WHAT WE ARE SEEING
TODAY...SO EXPECT HIGHS TO BE NO WARMER THAN WHAT WE ARE SEEING
TODAY AND LIKELY A COUPLE OF DEGREES COOLER IN WRN MN.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 400 PM CDT SUN AUG 30 2015
NO BIG CHANGES TO THE LONG TERM FORECAST AS THE PATTERN STILL
FAVORS RIDGING IN THE CENTRAL CONUS AND ABOVE NORMAL TEMPERATURES
LASTING INTO LABOR DAY WEEKEND.
THE LONGWAVE RIDGE AXIS WILL CONTINUE TO SHIFT EAST ON
TUESDAY...BUT THE BIGGEST RESERVOIR OF WARMTH WILL LINGER FROM THE
FOUR CORNERS UP THROUGH THE NORTHERN PLAINS. THE NAEFS
STANDARDIZED 850MB TEMPERATURE ANOMALIES ARE COMMONLY BETWEEN TWO
AND THREE SIGMA OVER THE NEXT WEEK IN THESE AREAS. AS THE 500MB
RIDGE AXIS SLIDES EAST ON TUESDAY THE LONGWAVE PATTERN LOSES SOME
OF ITS AMPLITUDE AND THE 850MB TEMPERATURE ADVECTION DECREASES
BEFORE REACHING THE FORECAST AREA. AS A RESULT...THE FORECAST AREA
WILL MAINTAIN MID 80S FOR HIGHS AS WE HEAD TOWARD MID WEEK...BUT
THE TEMPERATES WILL NOT APPROACH THE MID /AND EVEN UPPER/ 90S
THAT ARE CURRENTLY BEING OBSERVED IN THE DAKOTAS THIS AFTERNOON.
WESTERN MN IS ALREADY SEEING DEWPOINTS IN THE UPPER 60S AND
EASTERN MN AND WESTERN WI WILL SOON FOLLOW...THESE DEWPOINTS WILL
LINGER THROUGH THE WEEK AND THE DEWPOINT WILL MOST LIKELY HIT 70
DEGREES IN MANY LOCATIONS THIS WEEK. IN THE WED-THU TIME
FRAME...MUCH OF THE 12Z GUIDANCE HINTS AT THE CHANCE FOR RAIN WITH
MOISTURE TRANSPORT EMBEDDED IN THE LOW LEVEL SOUTHWEST FLOW. THE
FORCING ISNT EXTREMELY...BUT THERE IS ELEVATED INSTABILITY AND
THE CAP ISNT OVERLY STRONG EITHER WITH THE 12-14C AIR AT 700MB
REMAINING WEST OF THE AREA IN THE DAKOTAS. THEREFORE...WE
MAINTAINED THE SMALL POPS IN THE FORECAST...BUT ADMITTEDLY THERE
IS LOW CONFIDENCE ON TIMING/AMOUNTS AND EVEN IF THERE WILL BE MUCH
CONVECTIVE INITIATION LOCALLY.
THE PERSISTENT TROUGH OVER THE GULF OF ALASKA AND PACIFIC
NORTHWEST FINALLY LOOKS TO MAKE SOME EASTERN PROGRESS AS WE HEAD
TOWARD THE BACK HALF OF LABOR DAY WEEKEND. THE OPERATIONAL
GUIDANCE AND ENSEMBLE OUTPUT HAS SLIGHTLY SLOWED THE ARRIVAL OF
THE COLD FRONT...BUT AT THE VERY LEAST WE CAN SAY NEXT WEEKEND
LOOKS MORE UNSETTLED WITH A PATTERN SHIFT LOCALLY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1203 AM CDT MON AUG 31 2015
BEGINNING TO SEE CONDITIONS BECOME FAVORABLE FOR RAPID STRATUS
DEVELOPMENT AT TAF ISSUANCE TIME. VISIBILITIES HAVE FALLEN TO
BETWEEN 5-7SM OVER MUCH OF THE AREA AND A FEW SITES ARE NOW
REPORTING SCT-BKN IFR CIGS ACROSS NWRN IOWA/SWRN MN/ERN SD. KHCD
AND KSTC HAVE ALSO HAD SCT007/SCT010 OBS RESPECTIVELY. SO...IT
MAY TAKE ANOTHER COUPLE HOURS BUT STILL BELIEVE WIDESPREAD IFR
CIGS ARE LIKELY TONIGHT INTO EARLY MONDAY.
KMSP...PUSHED BACK THE TIMING OF THE ARRIVAL OF IFR CIGS A COUPLE
HOURS TO 07Z...WITH THE POTENTIAL FOR PERIODIC EPISODES OF VFR
UNTIL LATE TONIGHT. MORE LIKELY THAN NOT...TONIGHT WILL BE A
REPEAT OF THE LAST COUPLE.
/OUTLOOK FOR KMSP/
TUE-THU...VFR WINDS S 5-15 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...CLF
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
1118 PM MDT SUN AUG 30 2015
.UPDATE...
WE WILL BE MAKING A QUICK UPDATE LATE THIS EVENING TO CANCEL THE
RED FLAG WARNING THAT WAS IN EFFECT UNTIL MIDNIGHT FOR OUR CENTRAL
AND WESTERN AREAS. THE COLD FRONT HAS MOVED THROUGH THIS AREA AND
WINDS HAVE SWITCHED TO THE NORTHWEST AND WERE GUSTY FOR A BRIEF
TIME BUT HAVE SINCE RELAXED INTO THE 10 TO 20 MPH RANGE. IN
ADDITION...HUMIDITIES HAVE RISEN ABOVE 30 PERCENT ACROSS THE
AFFECTED AREA. HOOLEY
&&
.SHORT TERM...VALID FOR MON AND TUE...
A SEASONABLY STRONG COLD FRONT WILL CROSS THE REGION TONIGHT AND
LEAD INTO A PERIOD OF QUIET WEATHER MONDAY AND TUESDAY.
TONIGHT...THE 12 UTC MODELS AND MORE CONTEMPORARY HRRR MODEL RUNS
ARE IN GENERAL AGREEMENT IN SHOWING THE COLD FRONT MOVING THROUGH
THE LIVINGSTON AREA BETWEEN 6 PM AND 9 PM MDT...BILLINGS BETWEEN 7
PM AND 11 MDT...SHERIDAN BETWEEN 11 PM AND 3 AM MDT...AND MILES
CITY AND BAKER AFTER MIDNIGHT. WE EXPECT A SHIFT TO WEST-NORTHWEST
WINDS BEHIND THE FRONT WITH GUSTS TO 45 MPH BASED ON THE DEGREE OF
LOW- AND MID-LEVEL COLD AIR ADVECTION AND THERMAL GRADIENT IN THE
FRONTAL ZONE. THAT/S SUPPORTED BY MOS STATISTICAL OUTPUT /THE MAV
AND MET/ AS WELL. FORECAST SOUNDINGS DO SUGGEST THE BOUNDARY LAYER
MAY BE A BIT TOO DECOUPLED FOR FULL MOMENTUM TRANSFER OF THE 40 KT
WINDS THAT ARE SIMULATED WITHIN 3000 FT AGL OF THE GROUND...BUT WE
BELIEVE THE COLD AIR ADVECTION WILL OVERCOME THAT TENDENCY. A RED
FLAG WARNING CONTINUES THROUGH THE EVENING TO CONVEY THE RISK THIS
COLD FRONTAL PASSAGE WILL PRESENT FOLLOWING LATE-AFTERNOON MIX-OUT
OF GUSTY SOUTHWEST WINDS AND DRYING IN SOUTH CENTRAL MT.
WHERE PRECIPITATION IS CONCERNED...ISOLATED SHOWERS AND STORMS ARE
POSSIBLE WITH THE SHORTWAVE TROUGH PASSAGE DRIVING THE COLD FRONT
EASTWARD...MAINLY THIS EVENING. STRONG MID-LEVEL WINDS SUGGEST A
STRONG STORM IS POSSIBLE...BUT WE FEEL THAT RISK WILL GENERALLY BE
MITIGATED BY A LACK OF STRONGER INSTABILITY.
MONDAY...THE POST-FRONTAL AIR MASS WILL BE COOLER...DRIER...AND
STABLE. HIGHS WILL BE NEAR 80 F WITH AFTERNOON HUMIDITIES AROUND
20 PERCENT PER THE 12 UTC MULTI-MODEL CONSENSUS WE USED TO DERIVE
THE OFFICIAL FORECAST...BUT WIND/S WILL NOT BE ANYTHING TO WRITE
HOME ABOUT.
TUESDAY...DEEPER MIXING TO 700 MB OR MORE AND WARMING TEMPERATURES
ALOFT WITH SOUTHWEST FLOW WILL PROMOTE A WARM-UP INTO THE UPPER
80S AND LOWER 90S F. ATMOSPHERIC MOISTURE CONTENT WON/T CHANGE
TOO MUCH AND THE RESULT WILL BE EVEN LOWER HUMIDITIES WELL DOWN
INTO THE TEENS...THOUGH WINDS AREN/T EXPECTED TO BE STRONG ENOUGH
FOR ANY RED-FLAG-TYPE CONDITIONS. SCHULTZ
.LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN...
UPPER TROUGH OVER THE PACIFIC NORTHWEST WILL MOVE INLAND ON
WEDNESDAY AND THIS SETS UP DEEP SOUTHWEST FLOW OVER SOUTHERN
MONTANA AND NORTHERN WYOMING. HIGHS WILL APPROACH 90 DEGREES ON
WEDNESDAY AHEAD OF COLD FRONT. THIS FRONT WILL MOVE THROUGH
WEDNESDAY NIGHT AND BRING COOLER WEATHER FOR THE END OF THE WEEK.
IN FACT...THIS WILL MARK A DRAMATIC PATTERN CHANGE AS THE WESTERN
TROUGH SWINGS OVER THE NORTHERN ROCKIES THIS WEEKEND. THIS WILL
END THE WARM AND DRY REGIME AND PROVIDE COOLER TEMPERATURES AND A
CHANCE OF PRECIPITATION. SOME OF THE MOUNTAIN TOPS COULD EVEN SEE
A LITTLE SNOW SATURDAY AND SUNDAY...ALTHOUGH THE STRONGER FORCING
AND MOST LIKELY PRECIPITATION PLACEMENT...WOULD BE OVER NORTHERN
MONTANA. TWH
&&
.AVIATION...
STRONG SOUTHWEST WINDS WILL CONTINUE AT KLVM THIS AFTERNOON WITH
SOME GUSTS TO 35KTS. WIDELY SCATTERED SHOWERS AND THUNDERSTORMS
WILL DEVELOP THROUGH THIS EVENING AS A COLD FRONT APPROACHES. SOME
OF THE STORMS NORTHWEST OF BILLINGS COULD BE STRONG WITH WIND
GUSTS TO 45KTS. A COLD FRONT WILL MOVE THROUGH CENTRAL LOCATIONS
FROM KBIL TO KLVM FROM 02-04Z...KSHR 03-05Z AND KMLS AND KBHK
05-07Z. NORTHWEST WINDS WILL GUST TO 35KTS BEHIND THE FRONT.
TWH/AAG
&&
.PRELIMINARY POINT TEMP/POPS...
MON TUE WED THU FRI SAT SUN
-----------------------------------------------------------
BIL 054/082 054/089 059/090 055/075 048/069 047/070 045/071
20/U 00/U 01/U 11/B 23/T 33/T 22/T
LVM 045/080 046/086 051/085 048/072 041/067 038/069 039/073
20/K 00/K 01/B 23/T 44/T 44/T 32/T
HDN 054/083 053/092 057/094 056/080 048/075 048/072 046/073
20/U 00/U 11/U 11/B 22/T 22/T 22/T
MLS 057/082 055/092 059/097 059/081 051/077 049/073 047/072
30/U 00/U 00/U 11/B 22/T 22/T 22/T
4BQ 056/080 055/092 059/096 058/082 053/079 051/071 049/070
30/U 00/U 00/U 01/U 12/T 22/T 22/T
BHK 055/079 054/091 057/095 058/081 051/080 049/073 046/070
30/N 00/U 10/U 11/U 12/T 22/T 22/T
SHR 051/083 049/091 054/092 053/082 046/076 044/070 042/071
30/U 00/U 10/U 01/B 12/T 22/T 22/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1244 AM CDT MON AUG 31 2015
.UPDATE...
ISSUED AT 1244 AM CDT MON AUG 31 2015
CONVECTION HAS DEVELOPED RAPIDLY OVER WESTERN NORTH DAKOTA THE PAST
COUPLE OF HOURS. THE UPPER LEVEL SHORTWAVES MOVING NORTHEAST THROUGH
THE SOUTHWEST FLOW ALOFT WERE FORECAST BY THE SHORT TERM MODELS TO
MOVE INTO WESTERN NORTH DAKOTA BETWEEN 10 PM AND 1 AM CDT. SHOWERS
AND THUNDERSTORMS SHOULD CONTINUE OVERNIGHT ACROSS WESTERN NORTH
DAKOTA AND MOVE INTO THE MINOT/BISMARCK AREA BY 2-3 AM CDT...AND
INTO JAMESTOWN BEFORE SUNRISE. STORMS SHOULD BE SCATTERED IN
NATURE. SOME STORMS WERE ON THE STRONGER SIDE IN EASTERN
MONTANA...BUT AS THEY APPROACH THE MID-LEVEL THERMAL RIDGE AXIS OVER
CENTRAL NORTH DAKOTA...IT APPEARS THE STORMS WEAKEN A BIT.
ALSO...THE MORE NUMEROUS THE STORMS THE MORE SPREAD OUT THE
AVAILABLE ENERGY USE BECOMES...THUS DO NOT EXPECT SEVERE STORMS
THIS MORNING. NO SIGNIFICANT CHANGE IN THE OVERALL FORECAST THIS
UPDATE.
UPDATE ISSUED AT 946 PM CDT SUN AUG 30 2015
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE...WITH A TIME
LAGGED ENSEMBLE OF THE 23-01 UTC HRRR ITERATIONS AND THE 00 UTC
NAM NEST STILL HANDLING WELL THE ONGOING POST-FRONTAL CONVECTION
ACROSS EASTERN MONTANA AND INTO SOUTHWEST NORTH DAKOTA.
THUS...WILL FOLLOW THEIR SOLUTIONS FOR POPS THE REMAINDER OF THE
NIGHT.
UPDATE ISSUED AT 627 PM CDT SUN AUG 30 2015
AS OF 2330 UTC...A COLD FRONT WAS PROPAGATING ACROSS THE HIGHWAY
83 CORRIDOR...AND WILL CONTINUE ITS EASTWARD PROGRESSION THROUGH
THE EVENING. THEREAFTER...POST-FRONTAL CONVECTION IS EXPECTED TO
ENTER SOUTHWEST NORTH DAKOTA AROUND 05 UTC AND SPREAD NORTHEAST
THROUGH THE NIGHT. THIS IS IN ASSOCIATION WITH MULTIPLE IMPULSES
EMBEDDED IN SOUTHWEST FLOW ALOFT AHEAD OF THE STRONGER NORTHERN
US ROCKIES SHORTWAVE. GIVEN GOOD HANDLING OF ONGOING CONVECTION
THROUGH 23 UTC...USED A BLEND THE 20-22 UTC HRRR TIME LAGGED
ENSEMBLE AND 18 UTC NAM NEST.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 345 PM CDT SUN AUG 30 2015
COLD FRONT ACROSS NORTHWEST NORTH DAKOTA SUNDAY AFTERNOON IS
NEARLY ALIGNED WITH THE FLOW ALOFT AND THUS IS MOVING SLOWLY
EAST. IT APPEARS SOME SMOKE IS POOLING ALONG THE FRONTAL BOUNDARY
AND IMPACTING NORTHWEST NORTH DAKOTA WITH WILLISTON AROUND 2 MILES
IN HAZE/SMOKE SO FAR THIS AFTERNOON. WILL ADD A PERIOD OF SMOKEY
WEATHER FOR NORTHWEST NORTH DAKOTA THROUGH THE MID EVENING.
OTHERWISE WILL NOT MENTION MORE SMOKE TONIGHT. SCATTERED SHOWERS
AND ISOLATED THUNDERSTORMS WILL FOLLOW THE FRONT AS IT PROGRESSES
SLOWLY ACROSS THE STATE TONIGHT. KEPT POPS ON THE LOW SIDE WITH
NOT MUCH MORE THAN 30 PERCENT POPS TONIGHT ENDING MONDAY MORNING.
COOLER MONDAY WITH HIGHS IN THE MID 70S TO LOWER 80S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 345 PM CDT SUN AUG 30 2015
CONTINUED WARM TEMPERATURES AND SLIGHT/PERIODIC THUNDERSTORM
CHANCES WILL HIGHLIGHT THE EXTENDED FORECAST PERIOD NEXT WEEK.
A SIGNIFICANT PATTERN CHANGE IS THEN DEPICTED FOR LATE NEXT
WEEKEND INTO THE EARLY PORTIONS OF THE FOLLOWING WORK WEEK.
ON TUESDAY...MAINTAINED A SLIGHT CHANCE OF MAINLY EVENING AND
OVERNIGHT THUNDERSTORMS FOR THE DEVILS LAKE BASIN AND JAMES RIVER
VALLEY WITH MODELS STILL SHOWING INCREASING INSTABILITY WITH
DAYTIME HEATING COUPLED WITH AN INCREASING LOW LEVEL JET ACROSS
THE EASTERN HALF OF THE STATE. CAPPING DURING THE DAY MAY HOLD
OFF ON CONVECTION UNTIL AFTER 00Z.
BEYOND TUESDAY...OUR SOUTHWEST UPPER FLOW WILL CONTINUE THROUGH THE
END OF THE EXTENDED PERIOD WITH TROUGHING ACROSS THE PACIFIC
NORTHWEST AND RIDGING OFF TO OUR EAST. A QUASI-STATIONARY SURFACE
TROUGH COMBINED WITH ANY EMBEDDED WAVES ALOFT WILL PROVIDE A FOCUS
FOR MAINLY ISOLATED DAILY SHOWER AND THUNDERSTORM ACTIVITY. BEST
CHANCES APPEAR TO BE TOWARDS THE END OF THE WORK WEEK AND INTO
NEXT WEEKEND WHEN A STRONG UPPER JET APPROACHES THE NORTHERN
PLAINS. TEMPERATURES WILL REMAIN NEAR TO SLIGHTLY ABOVE NORMAL
THROUGH THE WORK WEEK WITH 80S TO LOW 90S FOR HIGHS THEN COOLING A
BIT INTO THE 70S AND 80S BY NEXT WEEKEND.
BOTH THE 12Z GFS/ECMWF THEN BRING A STRONG COLD FRONT THROUGH THE
REGION LATE NEXT WEEKEND OR EARLY NEXT WEEK. BOTH MODELS INDICATE
THE POTENTIAL FOR A SIGNIFICANT COOL DOWN WITH 850MB TEMPERATURES
3-5C DEGREES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1244 AM CDT MON AUG 31 2015
SCATTERED THUNDERSTORMS ARE EXPECTED TO CONTINUE TO DEVELOP OVER
WESTERN NORTH DAKOTA AND SPREAD EAST/NORTHEAST OVERNIGHT. THE
CONVECTION WAS MAINLY ALONG AND BEHIND THE COLD FRONT...WHICH
EXTENDED FROM NEAR KDVL TO NEAR KBIS...TO THE BORDER OF MT/WY/SD.
THE FRONT IS FORECAST TO MOVE EAST INTO THE JAMES VALLEY BY 12Z AND
REACHING THE RED RIVER VALLEY AROUND 18Z. THUNDERSTORM CHANCES
ENDING AT KISN/KDIK AROUND 12Z...ENDING AT KMOT/KBIS BY AROUND
15Z...AND ENDING AT KJMS BY AROUND 18Z. GUSTY WEST WINDS BEHIND THE
FRONT. SMOKE MAY BECOME MORE WIDESPREAD AND THICKER THROUGH THE DAY
MONDAY...BUT NOT CONFIDENT REGARDING AFFECTS AT THE SURFACE AND LEFT
MENTION OUT OF THE TAFS THIS PACKAGE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JV
SHORT TERM...WAA
LONG TERM...NH
AVIATION...JV
AREA FORECAST DISCUSSION...UPDATED
NWS NORMAN OK
1240 AM CDT MON AUG 31 2015
.DISCUSSION...
31/06Z TAF DISCUSSION BELOW.
&&
.AVIATION...
WILL MENTION MVFR BR AT KPNC THROUGH 15Z WITH SOME DENSE FOG NOT
OUT OF THE REALM OF POSSIBILITIES. OTHERWISE...VFR CONDITIONS
EXPECTED THROUGH PERIOD WITH RETURN TO SOUTHERLY WINDS.
&&
.PREV DISCUSSION... /ISSUED 927 PM CDT SUN AUG 30 2015/
UPDATE...
RAIN HAS ENDED ACROSS THE FA. THE REST OF THE NIGHT IS EXPECTED
TO REMAIN DRY BUT IT IS NOT COMPLETELY OUT OF THE QUESTION THAT A
FEW MORE ISOLATED SHOWERS/STORMS MAY DEVELOP IN SE PARTS OF THE
FA. HOWEVER... WILL KEEP POP/WX FORECAST DRY FOR NOW. CLOUDS IN
THE SE ARE EXPECTED TO GRADUALLY DECREASE OVERNIGHT. SOME PATCHY
FOG IS STILL POSSIBLE TOWARDS MORNING IN NORTHERN PARTS OF THE FA
SO WILL KEEP MENTION IN THE FORECAST. UPDATES OUT SOON.
PREV DISCUSSION... /ISSUED 610 PM CDT SUN AUG 30 2015/
AVIATION...
MAINLY VFR CONDITIONS EXPECTED THROUGH THE FORECAST
PERIOD. THERE IS AN OUTSIDE CHANCE FOR SOME PATCHY FOG ACROSS
NORTHERN OKLAHOMA OVERNIGHT... BUT CHANCES REMAIN TOO LOW TO MENTION
AT THIS POINT. WINDS WILL BECOME SOUTHERLY ON MONDAY WITH SOME GUSTS
APPROACHING 20KTS ACROSS THE WEST BY AFTN.
30
PREV DISCUSSION... /ISSUED 220 PM CDT SUN AUG 30 2015/
DISCUSSION...
MAINLY DRY WEATHER AND NEAR OR SLIGHTLY ABOVE AVERAGE TEMPERATURES
ARE EXPECTED DURING THE NEXT SEVEN DAYS.
THROUGH 10 PM THIS EVENING...A FEW THUNDERSTORMS MAY FORM NEAR A
WEAK SURFACE FRONT OVER SOUTHERN OKLAHOMA...NEAR WAURIKA TO
COALGATE. CAPPING IS RATHER STRONG...HOWEVER A MID LEVEL
WEAKNESS CENTERED OVER EASTERN OKLAHOMA MAY BE ENOUGH FOR TO
ALLOW FOR ISOLATED DEVELOPMENT. THUS...WENT WITH A 20 PERCENT
CHANCE IN THESE LOCATIONS. IF STORMS FORM...THEY WOULD BE SLOW
MOVERS...PRODUCE LOCALIZED DOWNPOURS...AND GUSTY WINDS PERHAPS UP
TO 50 TO 60 MPH. ANY CONVECTION WOULD DIMINISH WITH THE LOSS OF
DAYTIME HEATING.
AFTER 10 PM THIS EVENING INTO MONDAY MORNING...PATCHY FOG MAY FORM
AGAIN ACROSS MAINLY NORTHERN OKLAHOMA. LATEST HRRR RUNS HAVE BEEN
CONSISTENT WITH DEPICTING LOW CLOUDS AND FOG OVER NEAR ALVA...
ENID...AND CHEROKEE. THIS SEEMS REASONABLE AS HIGHER SURFACE
DEWPOINTS ARE FORECAST TO MOVE INTO THESE LOCATIONS LATE TONIGHT.
THUS...ADDED MENTION OF PATCHY FOG. DOUBT FOG WILL BE TOO DENSE
OR WIDESPREAD SINCE NO RAIN WILL OCCUR IN THESE LOCATIONS TODAY.
MONDAY WILL BE MOSTLY SUNNY AND HOTTER WITH INCREASING SOUTH
SURFACE WINDS. CANNOT COMPLETELY RULE OUT A STRAY AFTERNOON OR
EVENING STORM IN SOUTHEAST OF A WAURIKA TO ADA LINE WHERE MID
LEVEL TEMPERATURES WILL BE A BIT COOLER AND CAPPING IS A BIT
WEAKER...BUT WILL NOT MENTION DUE TO LOW CONFIDENCE OF OCCURRENCE.
MONDAY NIGHT THROUGH NEXT SUNDAY...SEASONABLY HOT AND MAINLY DRY
WEATHER WILL CONTINUE WITH A WEAK MID/UPPER RIDGE OVERHEAD. LOW
STORM CHANCES MAY RETURN TO MAINLY NORTHWESTERN OKLAHOMA BY THE
WEEKEND...BUT CONFIDENCE IS LOW.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 70 92 71 92 / 0 0 0 0
HOBART OK 71 96 71 95 / 0 0 0 0
WICHITA FALLS TX 72 97 73 96 / 0 0 0 0
GAGE OK 69 95 70 94 / 0 0 0 0
PONCA CITY OK 70 93 71 92 / 0 0 0 0
DURANT OK 71 94 71 94 / 0 10 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
25/30
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
548 AM EDT MON AUG 31 2015
.SYNOPSIS...
A MODERATELY HIGH AMOUNT OF MOISTURE STREAMING EAST FROM THE OHIO
VALLEY WILL EXTEND ACROSS PENN THROUGH MUCH OF THIS WEEK. THE
CLOSE PROXIMITY OF A NEARLY EAST-WEST FRONTAL BOUNDARY ACROSS
PENNSYLVANIA WILL LEAD TO ISOLATED MAINLY AFTERNOON AND EARLY
EVENING SHRA/TSRA TODAY THROUGH THURSDAY.
HIGH PRESSURE OFF THE EAST COAST WILL RIDGE NORTHWEST INTO
PENNSYLVANIA AND LEAD TO TEMPERATURES WELL ABOVE NORMAL THIS
ENTIRE WEEK. IT WILL FEEL MORE LIKE THE MIDDLE OF SUMMER THAN
SEPTEMBER.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SFC HIGH PRESSURE LOCATED JUST OFF THE SE U.S. COAST WILL SLOWLY
BUILD NORTHWEST...AS AN UPPER RIDGE LOCATED OVER THE UPPER GLAKES
AND MISS VALLEY MOVES EAST TO THE OHIO RIVER VALLEY AND MID
ATLANIC REGION BY 12Z TUES.
925-850 MB THETA-E RIDGE EXTENDS FROM THE OHIO VALLEY...ENE THROUGH
PENN EARLY TODAY...WITH A WEAK/STALLED-OUT SFC FRONT EXTENDING
FROM DETROIT...SW TO ST LOUIS. THE NORTHERN PART OF THIS FRONT
WILL MOVE STEADILY EAST/SOUTHEAST AND BECOME LOCATED ACROSS
CENTRAL PENN THIS EVENING...AND STAY THERE THROUGH MUCH OF
TUESDAY. A BIT OF DRYING WILL BE SEEN ACROSS THE REGION NEAR AND
TO THE NORTH OF INTERSTATE 80.
03Z SREF PROB OF CAPE EXCEEDING 1000 J/KG CLIMBS TO THE 60-80
PERCENT RANGE THIS AFTERNOON...HOWEVER THE PROB OF 2000 J/KG IS
VERY LOW AT 10 PERCENT OR LESS TODAY THROUGH THURSDAY...THUS THE
LOW DIURNAL POP/CVRG FOR CONVECTION. 07Z HRRR CONFIRMS THIS
THINKING AS IT PLACES GENERALLY ISOLATED- SCATTERED/POPCORN LIKE
COVERAGE BETWEEN 17Z-22Z TODAY.
PLENTY OF BKN-OVC ALTO CU /TOPPED BY SOME CIRRUS/ BLANKETED THE
SE HALF TO TWO-THIRDS OF PENN EARLY TODAY...WHILE MOSTLY CLEAR
SKIES AND THE COOLEST TEMPS IN THE L60S WERE FOUND INVOF KBFD.
ELSEWHERE...TEMPS RANGED FROM THE MID 60S TO MID 70S - A RATHER
MUGGY EARLY MORNING FOR THE FINAL DAY OF METEOROLOGICAL SUMMER.
ASIDE FROM A HIGHLY ISOLATED AND BRIEF LIGHT SHOWER OR TWO ON THE
RADAR SCOPE EARLY TODAY...CONDITIONS ACROSS MUCH OF CENTRAL AND
NORTHERN PENN WILL BE DRY WITH A VERY LIGHT AND VARIABLE WIND
THROUGH THE MID MORNING HOURS.
FARTHER SOUTH...WEAK UPPER LOW OVER THE WESTERN CAROLINAS WILL
LIFT NORTHWARD OVERNIGHT ON THE WESTERN PERIPHERY OF THE SPRAWLING
WESTERN ATLANTIC UPPER HIGH CIRCULATION. THIS WILL MAINTAIN THE
FOCUS FOR POOLING MOISTURE AND FORCING FOR SHOWER ACTIVITY THROUGH
THE PRE DAWN HOURS ACROSS MY FAR SOUTH. AGAIN...AREAS TO THE
NORTH SHOULD BE DRY AFTER 06Z AS DEFORMATION LESSENS AND FORCING
FOCUS SHIFTS TO AREAS ALONG AND SOUTH OF MY SOUTHERN TIER.
SOME FOG HAS FORMED...BUT VSBYS ARE HOLDING UP AOA 1 SM
MINS AROUND SUNRISE TODAY WILL RUN IN THE 60S IN PRACTICALLY ALL
LOCATIONS AS DEWPOINTS SHOULD NOT GO ANY LOWER THAN 60F. A FEW OF
THE NORMALLY COLD SPOTS NEAR...AND THE EAST OF KBFD WILL SEE A LOW
TEMP IN THE MID 50S.
HIGH TEMPS THIS AFTERNOON WILL VARY FROM THE U70S OVER THE HIGHEST
ELEVATIONS OF THE NORTH AND WEST...TO THE MID AND UPPER 80S ACROSS
OUR SE ZONES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
TONIGHT SHOULD BE A NEAR REPEAT OF SUNDAY NIGHT/EARLY MONDAY WITH
VARIABLE AMTS OF MAINLY MID AND HIGH CLOUDS AND PERHAPS JUST A
COUPLE SMALL SHOWERS ROAMING THE STREETS.
CONSALL TEMP BLEND YIELDS LOWS AROUND 60F ACROSS THE NRN
MTNS...AND INTHE MID TO UPPER 60S ELSEWHERE.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
ANOMALOUS UPPER LEVEL RIDGE WILL DOMINATE THE OHIO VALLEY AND
EASTERN UNITED STATES MUCH OF THE UPCOMING WEEK...WITH LATEST
GUIDANCE REMAINING FIRM FOR AN EXTENDED RUN OF 850HPA TEMPS
PEAKING DAILY AROUND 16-18C. THIS WILL TRANSLATE TO WELL ABOVE-
NORMAL SFC TEMPS. THIS WARMTH AND INCREASING HUMIDITY SHOULD ALLOW
FOR AT LEAST A SLIGHT CHC FOR DIURNAL CONVECTION EACH DAY...BUT
WARM MID-LEVELS WILL KEEP THE PROBABILITY OF WIDESPREAD RAINFALL
QUITE LOW.
BEST CHANCES FOR PRECIP WILL BE DURING THE MID-LATE WEEK PERIOD
/WED-THU-FRI/ WITH A COUPLE SUBTLE FEATURES. FIRST...A WEAK UPPER
LEVEL WAVE /BEST PROGGED ON THE ECMWF/ SLIPS OVERHEAD ON WED AS
BERMUDA HIGH BRIEFLY RECEDES. AT SAME TIME A WEAK BACKDOOR COLD
FRONT SLIPS SOUTHWARD OFF THE EAST COAST. THIS COULD HELP POOL
SOME LOW LEVEL MOISTURE OVER THE MID ATLANTIC AND OHIO VALLEY AS
MID LEVELS COOL JUST A BIT...BRINGING POTENTIAL FOR SCT TSTMS.
RIDGE BUILDS BACK IN FOR FRI...BUT ANOTHER SURFACE BACKDOOR FRONT
TRIES TO SLIP ACROSS THE STATE AS SURFACE HIGH EXPANDS IN FROM THE
NORTH. THIS BOUNDARY SHOULD BRING SCT CONVECTION FOR FRI.
EXTENDED MODELS HINT AT POTENTIAL FOR DAILY CONVECTION CONTINUING
INTO THE WEEKEND ALONG SOUTHER BORDER...BUT OVERALL CONDITIONS
WILL BE MAINLY RAIN-FREE.
TEMPS PEAK MIDWEEK WITH READINGS APPROACHING 90F IN THE SE...AND
EVEN GETTING INTO THE 80S ELSEHERE...EASILY WELL ABOVE NORMAL FOR
THE FIRST WEEK OF SEPT. LOWS WILL ALSO REMAIN QUITE MILD MID/LATE
WEEK AS HIGH HUMIDITY AIR HANGS AROUND. SLIGHTLY COOLER BUT STILL
ABOVE AVERAGE TEMPS WILL CONTINUE THROUGH THE WEEKEND.
&&
.AVIATION /10Z MONDAY THROUGH FRIDAY/...
REGIONAL RADAR AT 03Z STILL SHOWING A FEW ISOLATED SHOWERS ACROSS
SOUTHERN PA. LOSS OF HEATING SHOULD CAUSE THE REMAINING SHOWERS TO DISSIPATE
AFTER MIDNIGHT.
FOCUS OVERNIGHT WILL SHIFT TOWARD POTENTIAL OF FOG. LIGHT WIND
AND PTCLDY SKIES SHOULD PROMOTE LOCALLY DENSE VALLEY FOG AFTER
MIDNIGHT ACROSS NORTHERN PA. CLIMATOLOGY AND LATEST SREF/MOS
SUGGEST KBFD IS LIKELY TO EXPERIENCE IFR/LIFR VIS REDUCTIONS LATE
TONIGHT. ALSO...MAY HAVE TO CONTEND WITH DENSE FOG AT KIPT...WHERE
GROUND IS NOW WET FROM A SHOWER EARLIER THIS EVENING. COMPLICATING
FACTOR IS MID LVL CLOUDINESS OVERSPREADING THE SOUTHERN PART OF
THE STATE. FEEL CONFIDENT THESE MID LVL CLOUDS WILL BE THICK
ENOUGH TO DIMINISH THE RADIATIONAL COOLING AND ASSOC DENSE FOG
THREAT ACROSS SOUTHERN PA. HOWEVER...NOT AS CONFIDENT AT KIPT.
ANY AM VALLEY FOG ACROSS NORTHERN PA SHOULD BURN OFF BY LATE AM.
OTHERWISE...WIDESPREAD VFR CONDS AND LIGHT WIND APPEAR VERY
LIKELY MONDAY WITH ONLY ISOLD LATE DAY SHRA/TSRA POSSIBLE...AS
HIGH PRESSURE BUILDS OFF THE MID ATLANTIC COAST.
OUTLOOK...
TUE-FRI...PATCHY AM FOG POSS...MAINLY KBFD. ISOLD PM TSRA IMPACTS
POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/RXR
AVIATION...FITZGERALD/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
542 AM EDT MON AUG 31 2015
.SYNOPSIS...
A MODERATELY HIGH AMOUNT OF MOISTURE STREAMING EAST FROM THE OHIO
VALLEY WILL EXTEND ACROSS PENN THROUGH MUCH OF THIS WEEK. THE
CLOSE PROXIMITY OF A NEARLY EAST-WEST FRONTAL BOUNDARY ACROSS
PENNSYLAVNAI WILL LEAD TO ISOLATED MAINLY AFTERNOON AND EARLY
EVENING SHRA/TSRA TODAY THROUGH THURSDAY.
HIGH PRESSURE OFF THE EAST COAST WILL RIDGE NORTHWEST INTO
PENNSYLVANIA AND LEAD TO TEMPERATURES WELL ABOVE NORMAL THIS
ENTIRE WEEK. IT WILL FEEL MORE LIKE THE MIDDLE OF SUMMER THAN
SEPTEMBER.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SFC HIGH PRESSURE LOCATED JUST OFF THE SE U.S. COAST WILL SLOWLY
BUILD NORTHWEST...AS AN UPPER RIDGE LOCATED OVER THE UPPER GLAKES
AND MISS VALLEY MOVES EAST TO THE OHIO RIVER VALLEY AND MID
ATLANIC REGION BY 12Z TUES.
925-850 MB THETA-E RIDGE EXTENDS FROM THE OHIO VALLEY...ENE THROUGH
PENN EARLY TODAY...WITH A WEAK/STALLED-OUT SFC FRONT EXTENDING
FROM DETROIT...SW TO ST LOUIS. THE NORTHERN PART OF THIS FRONT
WILL MOVE STEADILY EAST/SOUTHEAST AND BECOME LOCATED ACROSS
CENTRAL PENN THIS EVENING...AND STAY THERE THROUGH MUCH OF
TUESDAY. A BIT OF DRYING WILL BE SEEN ACROSS THE REGION NEAR AND
TO THE NORTH OF INTERSTATE 80.
03Z SREF PROB OF CAPE EXCEEDING 1000 J/KG CLIMBS TO THE 60-80
PERCENT RANGE THIS AFTERNOON...HOWEVER THE PROB OF 2000 J/KG IS
VERY LOW AT 10 PERCENT OR LESS TODAY THROUGH THURSDAY...THUS THE
LOW DIURNAL POP/CVRG FOR CONVECTION. 07Z HRRR CONFIRMS THIS
THINKING AS IT PLACES GENERALLY ISOLATED- SCATTERED/POPCORN LIKE
COVERAGE BETWEEN 17Z-22Z TODAY.
PLENTY OF BKN-OVC ALTO CU /TOPPED BY SOME CIRRUS/ BLANKETED THE
SE HALF TO TWO-THIRDS OF PENN EARLY TODAY...WHILE MOSTLY CLEAR
SKIES AND THE COOLEST TEMPS IN THE L60S WERE FOUND INVOF KBFD.
ELSEWHERE...TEMPS RANGED FROM THE MID 60S TO MID 70S - A RATHER
MUGGY EARLY MORNING FOR THE FINAL DAY OF METEOROLOGICAL SUMMER.
ASIDE FROM A HIGHLY ISOLATED AND BRIEF LIGHT SHOWER OR TWO ON THE
RADAR SCOPE EARLY TODAY...CONDITIONS ACROSS MUCH OF CENTRAL AND
NORTHERN PENN WILL BE DRY WITH A VERY LIGHT AND VARIABLE WIND
THROUGH THE MID MORNING HOURS.
FARTHER SOUTH...WEAK UPPER LOW OVER THE WESTERN CAROLINAS WILL
LIFT NORTHWARD OVERNIGHT ON THE WESTERN PERIPHERY OF THE SPRAWLING
WESTERN ATLANTIC UPPER HIGH CIRCULATION. THIS WILL MAINTAIN THE
FOCUS FOR POOLING MOISTURE AND FORCING FOR SHOWER ACTIVITY THROUGH
THE PRE DAWN HOURS ACROSS MY FAR SOUTH. AGAIN...AREAS TO THE
NORTH SHOULD BE DRY AFTER 06Z AS DEFORMATION LESSENS AND FORCING
FOCUS SHIFTS TO AREAS ALONG AND SOUTH OF MY SOUTHERN TIER.
SOME FOG HAS FORMED...BUT VSBYS ARE HOLDING UP AOA 1 SM
MINS AROUND SUNRISE TODAY WILL RUN IN THE 60S IN PRACTICALLY ALL
LOCATIONS AS DEWPOINTS SHOULD NOT GO ANY LOWER THAN 60F. A FEW OF
THE NORMALLY COLD SPOTS NEAR...AND THE EAST OF KBFD WILL SEE A LOW
TEMP IN THE MID 50S.
HIGH TEMPS THIS AFTERNOON WILL VARY FROM THE U70S OVER THE HIGHEST
ELEVATIONS OF THE NORTH AND WEST...TO THE MID AND UPPER 80S ACROSS
OUR SE ZONES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
TONIGHT SHOULD BE A NEAR REPEAT OF SUNDAY NIGHT/EARLY MONDAY WITH
VARIABLE AMTS OF MAINLY MID AND HIGH CLOUDS AND PERHAPS JUST A
COUPLE SMALL SHOWERS ROAMING THE STREETS.
CONSALL TEMP BLEND YIELDS LOWS AROUND 60F ACROSS THE NRN
MTNS...AND INTHE MID TO UPPER 60S ELSEWHERE.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
ANOMALOUS UPPER LEVEL RIDGE WILL DOMINATE THE OHIO VALLEY AND
EASTERN UNITED STATES MUCH OF THE UPCOMING WEEK...WITH LATEST
GUIDANCE REMAINING FIRM FOR AN EXTENDED RUN OF 850HPA TEMPS
PEAKING DAILY AROUND 16-18C. THIS WILL TRANSLATE TO WELL ABOVE-
NORMAL SFC TEMPS. THIS WARMTH AND INCREASING HUMIDITY SHOULD ALLOW
FOR AT LEAST A SLIGHT CHC FOR DIURNAL CONVECTION EACH DAY...BUT
WARM MID-LEVELS WILL KEEP THE PROBABILITY OF WIDESPREAD RAINFALL
QUITE LOW.
BEST CHANCES FOR PRECIP WILL BE DURING THE MID-LATE WEEK PERIOD
/WED-THU-FRI/ WITH A COUPLE SUBTLE FEATURES. FIRST...A WEAK UPPER
LEVEL WAVE /BEST PROGGED ON THE ECMWF/ SLIPS OVERHEAD ON WED AS
BERMUDA HIGH BRIEFLY RECEDES. AT SAME TIME A WEAK BACKDOOR COLD
FRONT SLIPS SOUTHWARD OFF THE EAST COAST. THIS COULD HELP POOL
SOME LOW LEVEL MOISTURE OVER THE MID ATLANTIC AND OHIO VALLEY AS
MID LEVELS COOL JUST A BIT...BRINGING POTENTIAL FOR SCT TSTMS.
RIDGE BUILDS BACK IN FOR FRI...BUT ANOTHER SURFACE BACKDOOR FRONT
TRIES TO SLIP ACROSS THE STATE AS SURFACE HIGH EXPANDS IN FROM THE
NORTH. THIS BOUNDARY SHOULD BRING SCT CONVECTION FOR FRI.
EXTENDED MODELS HINT AT POTENTIAL FOR DAILY CONVECTION CONTINUING
INTO THE WEEKEND ALONG SOUTHER BORDER...BUT OVERALL CONDITIONS
WILL BE MAINLY RAIN-FREE.
TEMPS PEAK MIDWEEK WITH READINGS APPROACHING 90F IN THE SE...AND
EVEN GETTING INTO THE 80S ELSEHERE...EASILY WELL ABOVE NORMAL FOR
THE FIRST WEEK OF SEPT. LOWS WILL ALSO REMAIN QUITE MILD MID/LATE
WEEK AS HIGH HUMIDITY AIR HANGS AROUND. SLIGHTLY COOLER BUT STILL
ABOVE AVERAGE TEMPS WILL CONTINUE THROUGH THE WEEKEND.
&&
.AVIATION /10Z MONDAY THROUGH FRIDAY/...
REGIONAL RADAR AT 03Z STILL SHOWING A FEW ISOLATED SHOWERS ACROSS
SOUTHERN PA. LOSS OF HEATING SHOULD CAUSE THE REMAINING SHOWERS TO DISSIPATE
AFTER MIDNIGHT.
FOCUS OVERNIGHT WILL SHIFT TOWARD POTENTIAL OF FOG. LIGHT WIND
AND PTCLDY SKIES SHOULD PROMOTE LOCALLY DENSE VALLEY FOG AFTER
MIDNIGHT ACROSS NORTHERN PA. CLIMATOLOGY AND LATEST SREF/MOS
SUGGEST KBFD IS LIKELY TO EXPERIENCE IFR/LIFR VIS REDUCTIONS LATE
TONIGHT. ALSO...MAY HAVE TO CONTEND WITH DENSE FOG AT KIPT...WHERE
GROUND IS NOW WET FROM A SHOWER EARLIER THIS EVENING. COMPLICATING
FACTOR IS MID LVL CLOUDINESS OVERSPREADING THE SOUTHERN PART OF
THE STATE. FEEL CONFIDENT THESE MID LVL CLOUDS WILL BE THICK
ENOUGH TO DIMINISH THE RADIATIONAL COOLING AND ASSOC DENSE FOG
THREAT ACROSS SOUTHERN PA. HOWEVER...NOT AS CONFIDENT AT KIPT.
ANY AM VALLEY FOG ACROSS NORTHERN PA SHOULD BURN OFF BY LATE AM.
OTHERWISE...WIDESPREAD VFR CONDS AND LIGHT WIND APPEAR VERY
LIKELY MONDAY WITH ONLY ISOLD LATE DAY SHRA/TSRA POSSIBLE...AS
HIGH PRESSURE BUILDS OFF THE MID ATLANTIC COAST.
OUTLOOK...
TUE-FRI...PATCHY AM FOG POSS...MAINLY KBFD. ISOLD PM TSRA IMPACTS
POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/RXR
AVIATION...FITZGERALD/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
529 AM EDT MON AUG 31 2015
.SYNOPSIS...
A MODERATELY HIGH AMOUNT OF MOISTURE STREAMING EAST FROM THE OHIO
VALLEY WILL EXTEND ACROSS PENN THROUGH MUCH OF THIS WEEK. THE
CLOSE PROXIMITY OF A NEARLY EAST-WEST FRONTAL BOUNDARY ACROSS
PENNSYLAVNAI WILL LEAD TO ISOLATED MAINLY AFTERNOON AND EARLY
EVENING SHRA/TSRA TODAY THROUGH THURSDAY.
HIGH PRESSURE OFF THE EAST COAST WILL RIDGE NORTHWEST INTO
PENNSYLVANIA AND LEAD TO TEMPERATURES WELL ABOVE NORMAL THIS
ENTIRE. IT WILL FEEL MORE LIKE THE MIDDLE OF SUMMER THAN
SEPTEMBER.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SFC HIGH PRESSURE LOCATED JUST OFF THE SE U.S. COAST WILL SLOWLY
BUILD NORTHWEST AS AN UPPER RIDGE LOCATED OVER THE UPPER GLAKES
AND MISS VALLEY MOVES EAST TO THE OHIO RIVER VALLEY AND MID
ATLANIC REGION BY 12Z TUES.
925-850 MB THETA-E RIDGE EXTENDS FROM THE OHIO VALLEY...ENE THROUGH
PENN EARLY TODAY...WITH A WEAK...STALLED-OUT SFC FRONT EXTENDING
FROM DETROIT...SW TO ST LOUIS. THE NORTHERN PORTIONS OF THIS FRONT
WILL MOVE STEADILY EAST/SOUTHEAST AND BECOME LOCATED ACROSS
CENTRAL PENN THIS EVENING...THROUGH MUCH OF TUESDAY. A BIT OF
DRYING WILL BE SEEN ACROSS THE REGION NEAR AND TO THE NORTH OF
INTERSTATE 80.
03Z SREF PROB OF CAPE EXCEEDING 2000 J/KG IS VERY LOW AT 10
PERCENT OR LESS TODAY THROUGH THURSDAY...THUS THE LOW DIURNAL
POP/CVRG FOR CONVECTION. 07Z HRRR CONFIRMS THIS THINKING AS IT
PLACES GENERALLY ISOLATED-SCATTERED/POPCORN LIKE COVERAGE BETWEEN
17Z-22Z TODAY.
PLENTY OF BKN-OVC ALTO CU /TOPPED BY SOME CIRRUS/ BLANKETED THE
SE HALF TO TWO-THIRDS OF PENN EARLY TODAY...WHILE MOSTLY CLEAR
SKIES AND THE COOLEST TEMPS IN THE L60S WERE FOUND INVOF KBFD.
ELSEWHERE...TEMPS RANGED FROM THE MID 60S TO MID 70S - A RATHER
MUGGY EARLY MORNING FOR THE FINAL DAY OF METEOROLOGICAL SUMMER.
ASIDE FROM A HIGHLY ISOLATED AND BRIEF LIGHT SHOWER OR TWO ON THE
RADAR SCOPE EARLY TODAY...CONDITIONS ACROSS MUCH OF CENTRAL AND
NORTHERN PENN WILL BE DRY WITH A VERY LIGHT AND VARIABLE WIND
THROUGH THE MID MORNING HOURS.
FARTHER SOUTH...WEAK UPPER LOW OVER THE WESTERN CAROLINAS WILL
LIFT NORTHWARD OVERNIGHT ON THE WESTERN PERIPHERY OF THE SPRAWLING
WESTERN ATLANTIC UPPER HIGH CIRCULATION. THIS WILL MAINTAIN THE
FOCUS FOR POOLING MOISTURE AND FORCING FOR SHOWER ACTIVITY THROUGH
THE PRE DAWN HOURS ACROSS MY FAR SOUTH. AGAIN...AREAS TO THE
NORTH SHOULD BE DRY AFTER 06Z AS DEFORMATION LESSENS AND FORCING
FOCUS SHIFTS TO AREAS ALONG AND SOUTH OF MY SOUTHERN TIER.
SOME FOG HAS FORMED...BUT VSBYS ARE HOLDING UP AOA 1 SM
MINS AROUND SUNRISE TODAY WILL RUN IN THE 60S IN PRACTICALLY ALL
LOCATIONS AS DEWPOINTS SHOULD NOT GO ANY LOWER THAN 60F. A FEW OF
THE NORMALLY COLD SPOTS NEAR...AND THE EAST OF KBFD WILL SEE A LOW
TEMP IN THE MID 50S.
HIGH TEMPS THIS AFTERNOON WILL VARY FROM THE U70S OVER THE HIGHEST
ELEVATIONS OF THE NORTH AND WEST...TO THE MID AND UPPER 80S ACROSS
OUR SE ZONES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
TONIGHT SHOULD BE A NEAR REPEAT OF SUNDAY NIGHT/EARLY MONDAY WITH
VARIABLE AMTS OF MAINLY MID AND HIGH CLOUDS AND PERHAPS JUST A
COUPLE SMALL SHOWERS ROAMING THE STREETS.
CONSALL TEMP BLEND YIELDS LOWS AROUND 60F ACROSS THE NRN
MTNS...AND INTHE MID TO UPPER 60S ELSEWHERE.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
ANOMALOUS UPPER LEVEL RIDGE WILL DOMINATE THE OHIO VALLEY AND
EASTERN UNITED STATES MUCH OF THE UPCOMING WEEK...WITH LATEST
GUIDANCE REMAINING FIRM FOR AN EXTENDED RUN OF 850HPA TEMPS
PEAKING DAILY AROUND 16-18C. THIS WILL TRANSLATE TO WELL ABOVE-
NORMAL SFC TEMPS. THIS WARMTH AND INCREASING HUMIDITY SHOULD ALLOW
FOR AT LEAST A SLIGHT CHC FOR DIURNAL CONVECTION EACH DAY...BUT
WARM MID-LEVELS WILL KEEP THE PROBABILITY OF WIDESPREAD RAINFALL
QUITE LOW.
BEST CHANCES FOR PRECIP WILL BE MIDWEEK /WED-THU-FRI/ WITH A
COUPLE SUBTLE FEATURES. FIRST...A WEAK UPPER LEVEL WAVE /BEST
PROGGED ON THE ECMWF/ SLIPS OVERHEAD ON WED AS BERMUDA HIGH
BRIEFLY RECEDES. AT SAME TIME A WEAK BACKDOOR COLD FRONT SLIPS
SOUTHWARD OFF THE EAST COAST. THIS COULD HELP POOL SOME LOW LEVEL
MOISTURE OVER THE MID ATLANTIC AND OHIO VALLEY AS MID LEVELS COOL
JUST A BIT...BRINGING POTENTIAL FOR SCT TSTMS. RIDGE BUILDS BACK
IN FOR FRI...BUT ANOTHER SURFACE BACKDOOR FRONT TRIES TO SLIP
ACROSS THE STATE AS SURFACE HIGH EXPANDS IN FROM THE NORTH. THIS
BOUNDARY SHOULD BRING SCT CONVECTION FOR FRI.
EXTENDED MODELS HINT AT POTENTIAL FOR DAILY CONVECTION CONTINUING
INTO THE WEEKEND ALONG SOUTHER BORDER...BUT OVERALL CONDITIONS
WILL BE MAINLY RAIN-FREE.
TEMPS PEAK MIDWEEK WITH READINGS APPROACHING 90F IN THE SE...AND
EVEN GETTING INTO THE 80S ELSEHERE...EASILY WELL ABOVE NORMAL FOR
THE FIRST WEEK OF SEPT. LOWS WILL ALSO REMAIN QUITE MILD MID/LATE
WEEK AS HIGH HUMIDITY AIR HANGS AROUND. SLIGHTLY COOLER BUT STILL
ABOVE AVERAGE TEMPS WILL CONTINUE THROUGH THE WEEKEND.
&&
.AVIATION /09Z MONDAY THROUGH FRIDAY/...
REGIONAL RADAR AT 03Z STILL SHOWING A FEW ISOLATED SHOWERS ACROSS
SOUTHERN PA. LOSS OF HEATING SHOULD CAUSE THE REMAINING SHOWERS TO DISSIPATE
AFTER MIDNIGHT.
FOCUS OVERNIGHT WILL SHIFT TOWARD POTENTIAL OF FOG. LIGHT WIND
AND PTCLDY SKIES SHOULD PROMOTE LOCALLY DENSE VALLEY FOG AFTER
MIDNIGHT ACROSS NORTHERN PA. CLIMATOLOGY AND LATEST SREF/MOS
SUGGEST KBFD IS LIKELY TO EXPERIENCE IFR/LIFR VIS REDUCTIONS LATE
TONIGHT. ALSO...MAY HAVE TO CONTEND WITH DENSE FOG AT KIPT...WHERE
GROUND IS NOW WET FROM A SHOWER EARLIER THIS EVENING. COMPLICATING
FACTOR IS MID LVL CLOUDINESS OVERSPREADING THE SOUTHERN PART OF
THE STATE. FEEL CONFIDENT THESE MID LVL CLOUDS WILL BE THICK
ENOUGH TO DIMINISH THE RADIATIONAL COOLING AND ASSOC DENSE FOG
THREAT ACROSS SOUTHERN PA. HOWEVER...NOT AS CONFIDENT AT KIPT.
ANY AM VALLEY FOG ACROSS NORTHERN PA SHOULD BURN OFF BY LATE AM.
OTHERWISE...WIDESPREAD VFR CONDS AND LIGHT WIND APPEAR VERY
LIKELY MONDAY WITH ONLY ISOLD LATE DAY SHRA/TSRA POSSIBLE...AS
HIGH PRESSURE BUILDS OFF THE MID ATLANTIC COAST.
OUTLOOK...
TUE-FRI...PATCHY AM FOG POSS...MAINLY KBFD. ISOLD PM TSRA IMPACTS
POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/RXR
AVIATION...FITZGERALD/CERU
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
328 AM MDT MON AUG 31 2015
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
ISSUED AT 327 AM MDT MON AUG 31 2015
WATER VAPOR IMAGERY SHOWS STRONG UPPER WAVE CROSSING CNTRL TO ERN MT
INTO NRN WY. SURFACE ANALYSIS SHOWS LOW PRES ACROSS THE WRN/CNTRL
DAKOTAS AHEAD OF THE UPPER WAVE...WITH A COLD FRONT QUICKLY PUSHING
THRU ERN MT/CNTRL WY TOWARD THE CWA. TEMPS ACROSS THE CWA ARE IN THE
60S/70S...EVEN 80S ACROSS THE DOWNSLOPING N/NE BLKHLS. BEHIND THE
FRONT...OBS SHOWING TEMPS DROPPING INTO THE 50S WITH WINDS OF 15 TO
30 GUSTING TO 30 TO 40 MPH. RADAR SHOWS SHOWER ACTIVITY CROSSING WRN
SD...HOWEVER NEARLY ALL THE PRECIP IS VIRGA WITH LITTLE TO NO RAIN
REACHING THE GROUND. THE COLD FRONT WILL PUSH THROUGH NE WY TO WRN
SD IN THE NEXT 4/5 HOURS OR SO...AND CLEAR SCNTRL SD BY MID TO LATE
MORNING. HRRR SUGGESTS WINDS WILL GENERALLY BE 15 TO 25 MPH WITH
GUSTS TO 30 TO 40 MPH...BUT IS ALSO SHOWING STRONGER WINDS ACROSS
THE WRN SD PLAINS NORTH AND EAST OF THE BLKHLS. WIND ADVISORY
CRITERIA WINDS ARE EXPECTED...HOWEVER JUST FOR COUPLE HOURS OR SO
IMMEDIATELY AFTER THE FROPA. COULD SEE LINGERING SHRA ACTIVITY EARLY
THIS MORNING AS MODELS ARE HAVING A HARD TIME DECIDING HOW MUCH
PRECIP WILL REACH THE GROUND. WILL LEAN TOWARD A DRY FORECAST FOR
NOW CONSIDERING THE LATEST RADAR IMAGERY...BUT WILL REASSESS CLOSER
TO 12Z. OTHERWISE A DRY DAY IS EXPECTED WITH MUCH COOLER
TEMPERATURES AND CLEARING SKIES. HIGHS WILL REACH THE UPPER 70S TO
UPPER 80S. TEMPS TONIGHT WILL DROP INTO THE 50S TO LOWER 60S. RETURN
FLOW WILL SET UP BY MON NGHT/TUE MRNG WITH WARMER TEMPS EXPECTED.
HIGHS WILL RETURN TO THE MID 80S TO MID 90S. DRY WEATHER WILL
CONTINUE TUE/TUE NGHT WITH BROAD SWRLY FLOW ALOFT PERSISTING.
.LONG TERM...WEDNESDAY THROUGH SUNDAY
ISSUED AT 327 AM MDT MON AUG 31 2015
THE UPPER TROUGH WILL REMAIN OVER THE NORTH AMERICAN PACIFIC
COAST THROUGH MOST OF THE WEEK...EVENTUALLY MOVING INLAND BY THE
WEEKEND AS ANOTHER IMPULSE DROPS INTO THE UPPER TROUGH FROM THE
NORTHWEST. THIS PATTERN WILL LEAD TO CONTINUED VERY WARM
TEMPERATURES OVER THE NORTHERN PLAINS BOTH WEDNESDAY AND THURSDAY.
FRIDAY AND SATURDAY WILL BE SLIGHTLY COOLER...WITH MUCH COOLER
TEMPS ON SUNDAY AND MONDAY BEHIND A RELATIVELY STRONG COLD FRONT
WHICH WILL PASS THROUGH THE AREA EARLY SUNDAY. DRY WEATHER IS
EXPECTED ON WEDNESDAY AND THURSDAY WITH A CHANCE OF THUNDERSTORMS
EACH DAY FROM FRIDAY THROUGH THE WEEKEND AS A SERIES OF UPPER
IMPULSES CROSS THE REGION AND COOLER AIR FLOWS IN AT THE SFC.
&&
.AVIATION...FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING
ISSUED AT 327 AM MDT MON AUG 31 2015
BREEZY NORTHWEST WINDS WILL FOLLOW A COLD FRONT THIS MORNING. VFR
CONDITIONS ARE EXPECTED TODAY AND TONIGHT.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
SHORT TERM...13
LONG TERM...10
AVIATION...10
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
358 AM CDT MON AUG 31 2015
.SHORT TERM /TODAY THROUGH TUESDAY/...FORECAST CHALLENGE FOR THE SHORT
TERM WILL BE PRECIPITATION CHANCES AND PLACEMENT.
EARLY MORNING WATER VAPOR IMAGERY DEPICTS A MID LEVEL LOW PRESSURE
AREA SPINNING NICELY ACROSS SOUTH CENTRAL TEXAS WITH A FINGER OF DRY
AIR ADVECTING INTO TO THE WESTERN CWA ON THE SOUTHSIDE OF THIS
FEATURE. TIME HEIGHTS SHOW THIS DRY AIR NICELY IN THE 600-400MB
LAYER. THIS LOW PRESSURE AREA IS LOCATED WITHIN A BROAD TROUGH
EXTENDING FROM NORTHEAST MEXICO NORTHEASTWARD THROUGH EASTERN
ARKANSAS. PWAT ON THE 00Z BRO SOUNDING WAS 1.93 INCHES WITH EVEN
HIGHER PWATS SOUTHWARD INTO THE BAY OF CAMPECHE ACCORDING TO BLENDED
TPW PRODUCTS. AT THIS HOUR CONVECTION IN THE GULF IS INCREASING
AHEAD OF DEEPER MOISTURE AND LARGE SCALE LIFT.
TROUGH AXIS WILL MOVE SLOWLY EASTWARD TODAY FROM ITS PRESENT
LOCATION LEAVING THE AREA IN FAVORABLE LARGE SCALE LIFT. MID LEVEL
DRY AIR WILL QUICKLY MOISTEN THROUGH THE MORNING HOURS WITH
FAVORABLE SFC-700MB MOISTURE PROFILE. LOOKING UPSTAIRS AT
250MB...THERE IS SOME WEAK SPEED DIFFLUENCE IN CYCLONIC FLOW SOUTH
OF THE LOW AND TROUGH AXIS. NOT MUCH TO HANG YOUR HAT ON AT THE
SURFACE EXCEPT FOR WEAK SPEED AND DIRECTIONAL CONVERGENCE SO THE
SEABREEZE WILL BECOME ACTIVE LATER THIS MORNING WITH CONVECTION
SPREADING WESTWARD WITH TIME. HRRR SHOWS INITIATION IN THE COASTAL
SECTIONS AROUND 16Z THEN SPREADING WESTWARD AND I FOLLOWED THIS
TREND. EXPECT SCATTERED COVERAGE OF CONVECTION WITH BRIEF HEAVY
RAINFALL AND GUSTY WINDS CORRESPONDING TO INVERTED-V FORECAST
SOUNDINGS ACROSS MUCH OF THE AREA.
CONVECTION WILL WANE IN THE EVENING HOURS REACHING THE FAR WESTERN
SECTIONS. HIGHER PWAT AND MOISTURE WILL BE ADVECTED ACROSS THE AREA
TONIGHT INTO TUESDAY. DEEPER MOISTURE ARRIVES AS THE LARGE SCALE
LIFT MOVES EAST OF THE AREA AND THE TROUGH AXIS IS DIRECTLY
OVERHEAD. THEREFORE...LARGE SCALE LIFT IS NEUTRAL. CONVECTION WILL
GET GOING OVERNIGHT ONCE AGAIN ACROSS THE GULF WATERS THEN SPREAD
INLAND AND DEVELOP ON THE SEABREEZE ONCE AGAIN. A LITTLE COOLER MID
LEVEL TEMPERATURES WILL LEAD TO SLIGHTLY BETTER CAPES AND
INSTABILITY. GUSTY WINDS AND HEAVY DOWNPOURS WILL BE OF CONCERN ONCE
AGAIN TUESDAY.
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...500MB TROUGH AXIS TO
LINGER ALONG THE TEXAS COAST EXTENDING INTO THE RGV WEDNESDAY
THEN SHIFT EASTWARD THURSDAY BEFORE SOME OF THE ENERGY SPLITS AND
THE SOUTHERN END OF THE TROUGH TAKES ON A RETROGRADING TRACK AS AN
INVERTED TROUGH FRIDAY INTO SATURDAY. GFS ENSEMBLE MEAN AND
DETERMINISTIC MODELS ARE MORE DISTINCT WITH THE SOUTHERN ENERGY
/INVERTED TROUGH/ WITH WITH THE ECMWF NOT AS TRANSPARENT
INDICATING MORE ENERGY REMAINING WITH THE TROUGH RESIDING OVER THE
SE U.S. MOISTURE FIELDS AND POPS GUIDANCE TREND DOWN WEDNESDAY AND
THURSDAY FROM THE HIGH POPS OF MONDAY AND TUESDAY. GFS/MAV TRENDS
UP FRIDAY AS THE INVERTED TROUGH APPROACHES. ECMWF CONTINUES TO
HAVE A HIGH POP BIAS BUT SHOWS A DOWNWARD TREND THROUGH THE WEEK.
THE FORECAST IS LEANING MORE WITH GFS AND ITS STRONGER SOUTHERN
INVERTED TROUGH FEATURE WITH BOTH THE EMSEMBLE AND DETERMINISTIC
SOLUTIONS IN BETTER AGREEMENT THEN THE DIVERGING OR WEAKER ECMWF.
FORECAST TAKES ON A GENERAL MIDDLE OF THE ROAD TREND WITH
ISOLATED TO SCATTERED CONVECTION WITH WEDNESDAY AND FRIDAY AND
POSSIBLY NEXT SATURDAY SEEING THE HIGHEST CHANCES BETTER OVERALL
AREAL COVERAGE. DIFFICULT TO PINPOINT IF THE EAST WILL SEE MORE
PRECIPITATION THAN THE WEST ON ANY PARTICULAR DAY AS WE MOVE INTO
OUR RAINIEST MONTH. MODELS SUGGEST AN AVERAGE MOISTURE CONTENT
THROUGH THE ATMOSPHERIC COLUMN WITH PWATS AROUND 1.75 INCH RANGE.
DO NOT SEE ANY DEEP TROPICAL MOISTURE THAT WOULD RAISE THE CONCERN
OF HEAVY RAIN AT THIS TIME BUT ISOLATED DOWNPOURS ARE NOT OUT OF
QUESTION WITH ANY STORMS THAT DO DEVELOP. TEMPERATURES TO AVERAGE
NEAR SEASONAL NORMALS WITH NO EXTREMES INDICATED.
&&
.MARINE...NOW THROUGH TUESDAY...WEAK HIGH PRESSURE WILL SUPPORT
LIGHT TO MODERATE SOUTHEAST WINDS AND LOW SEAS. SHOWERS AND
THUNDERSTORMS WILL INCREASE TODAY THROUGH TUESDAY DUE TO
INSTABILITY ALOFT AND INCREASED MOISTURE MOVING UP FROM SOUTH OF
THE AREA.
TUESDAY NIGHT THROUGH FRIDAY...BROAD HIGH PRESSURE TO REMAIN OVER
THE GULF WITH A WEAK UPPER LEVEL TROUGH OVER THE NORTHWEST AND
NORTH CENTRAL GULF. LIGHT ONSHORE WINDS AND SLIGHT SEAS TO PERSIST
INTO THURSDAY. A MID LEVEL INVERTED TROUGH TO TRACK THROUGH THE
LOWER TEXAS COASTAL WATERS FRIDAY INTO SATURDAY WIND A SLIGHT
INCREASE OF ONSHORE WINDS AND SLIGHT UPTICK OF SEAS. DAILY SHOWERS
AND THUNDERSTORMS ARE EXPECTED WITH BEST CHANCES WEDNESDAY AND
FRIDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL 90 78 90 77 / 30 40 50 20
BROWNSVILLE 92 76 91 76 / 40 40 50 20
HARLINGEN 93 75 93 75 / 40 30 50 20
MCALLEN 96 78 96 78 / 40 20 40 20
RIO GRANDE CITY 97 76 98 75 / 30 20 30 20
SOUTH PADRE ISLAND 85 79 86 80 / 30 40 50 20
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
55...SHORT TERM
59...LONG TERM
65...GRAPHICS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
340 AM CDT MON AUG 31 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 340 AM CDT MON AUG 31 2015
EARLY THIS MORNING...LOW STRATUS HAS QUICKLY DEVELOPED ACROSS
NORTH-CENTRAL IA AND ALONG THE MN/IA BORDER AS WELL AS ACROSS
NORTHERN WI. 31.07Z RAP SHOWS THIS STRATUS FILLING-IN ACROSS MUCH
OF THE FORECAST AREA BY SUNRISE. THESE CLOUDS...COMBINED WITH
BRISK WEST-SOUTHWEST WIND JUST OFF THE SURFACE SHOULD PRECLUDE
WIDESPREAD DENSE FOG...BUT CAN STILL EXPECT SOME AREAS OF REDUCED
VISIBILITY...ESPECIALLY FOR THOSE AREAS THAT REMAIN MOSTLY CLEAR
FOR A LONGER PERIOD.
AS QUICKLY AS THE STRATUS DEVELOPS...MOST HIGH RESOLUTION MODELS
DISSIPATE IT JUST AS QUICKLY BY LATE MORNING AS 15 TO 20 KTS MIX
WITHIN DEEPENING BOUNDARY LAYER. EXPECT A RETURN TO AT LEAST
PARTLY SUNNY SKIES BY EARLY AFTERNOON. PRIMARY IMPACT OF CLOUDS
WILL BE TO SLOW TEMPERATURE RISE THROUGH THE DAY...SO DROPPED
AFTERNOON HIGHS A FEW DEGREES INTO THE LOWER TO MID 80S.
TONIGHT NOT LIKELY TO BE COMPLETELY CLOUD FREE AND WITH 10 TO 20
KTS ATOP NOCTURNAL INVERSION...FOG THREAT SHOULD BE LOWER THAN THE
PAST COUPLE NIGHTS. TEMPERATURES WILL DROP INTO THE MID TO UPPER
60S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 340 AM CDT MON AUG 31 2015
MAIN STORY FOR THE WEEK CONTINUES TO BE WELL ABOVE NORMAL
TEMPERATURES WITH A BROAD 500 HPA RIDGE PARKED ACROSS THE EASTERN
CONUS. WITH 925 HPA TEMPERATURES GENERALLY WOBBLING BETWEEN 24 AND
26 CELSIUS...DAILY HIGHS HIGHS WILL TOP OUT IN THE MID TO UPPER
80S WITH SOME 90 PLUS DEGREE READINGS ALONG AND EAST OF THE MS
RIVER.
WILL KEEP 20-30 PERCENT MODEL CONSENSUS POPS WEDNESDAY NIGHT
THROUGH FRIDAY...BUT THINK MAJORITY OF THE WEEK WILL REMAIN DRY.
MULTIPLE WEAK/ILL-RESOLVED SHORT-WAVES MOVE ACROSS THE REGION IN
SOUTHWEST FLOW ALOFT THAT COULD PROVIDE A FOCUSING MECHANISM FOR
CONVECTION. HOWEVER...AXIS OF MAXIMUM MID-LEVEL MOISTURE TRANSPORT
REMAINS WEST OF THE FORECAST AREA...CLOSER TO THE WESTERN CONUS
TROUGH. DAILY INSTABILITY IS PRESENT WITH ABOVE NORMAL TEMPERATURES/
SURFACE DEWPOINTS IN THE 60S...BUT LARGE SCALE RIDGE SQUASHES ANY
DEEP LAYER SHEAR OF SIGNIFICANCE. FOR NOW...DIFFICULT TO PROVIDE
DETAILS ON TIMING OR COVERAGE IF ANYTHING DOES DEVELOP SO BROAD-
BRUSHED POPS SEEM REASONABLE.
BETTER CHANCES FOR SHOWERS AND THUNDERSTORMS RETURN SATURDAY NIGHT
INTO SUNDAY AS 31.00Z GFS/ECMWF ATTEMPT TO BREAK DOWN EASTERN
CONUS RIDGE BY MOVING A BROAD PACIFIC TROUGH INTO THE ROCKIES/
NORTHERN PLAINS. GFS IS MUCH QUICKER IN DOING SO COMPARED TO THE
SLOWER ECMWF...SO DEFINITE TIMING ISSUES EMERGE. FOR NOW...A
BLENDED APPROACH IS PRUDENT RESULTING IN CHANCE POPS SATURDAY
NIGHT THROUGH THE DAY ON SUNDAY. SHOULD SEE TEMPERATURES FALL BACK
TO MORE SEASONABLE LEVELS ONCE TROUGH PASSES...BUT WHETHER THIS
OCCURS BY SUNDAY OR EARLY NEXT WEEK IS YET TO BE SEEN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1125 PM CDT SUN AUG 30 2015
LIGHT SFC WINDS...HIGH PRESSURE IN THE VICINITY...AND T/TD SPREAD
AROUND 2 F AT LATE EVENING ALL SUPPORT DENSE FOG IN THE RIVER VALLEY
AT KLSE. HOWEVER...THE DEPTH OF THE LIGHT WIND LAYER DOES NOT.
BUFKIT HRRR/RAP/NAM SOUNDINGS ALL POINT TO 10+ KTS OF WIND WITHIN A
COUPLE HUNDRED FEET OF THE SURFACE. THIS STIRRING GENERALLY
PRECLUDES DENSE FOG FORMATION IN THE VALLEY - OR AT LEAST ITS
ABILITY TO SPREAD. IN ADDITION...IT CAN WORK AGAINST A LOW STRATUS
LAYER DEVELOPING. HOWEVER...WITH WIDESPREAD LOW LEVEL SATURATION
ACROSS THE REGION...MVFR BR IS CERTAINLY POSSIBLE...AT KLSE AND
KRST.
AS FOR CIGS...HRRR/RAP INCREASE THE LOW SATURATION ACROSS THE
SOUTH...WHICH COULD MANIFEST AS LOW STRATUS AND/OR THICK FOG. LATEST
RUNS KEEP THIS STRATUS/FOG THREAT SOUTH OF THE TAF SITES...AND WILL
HAVE THE FORECAST FOLLOW SUIT.
IT WILL BE ANOTHER EARLY MORNING OF CLOSELY FOLLOWING
OBS/TRENDS...WITH UPDATES MADE IF NEEDED.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...ROGERS
LONG TERM...ROGERS
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
901 AM EDT MON AUG 31 2015
.DISCUSSION...
...FLOOD WATCH CONTINUES AREAWIDE THROUGH EARLY THIS EVENING...
CURRENT-TONIGHT...MORNING 915MHZ CAPE PROFILES SHOW DEEP SSE/S FLOW
FROM THE SURFACE THROUGH 10.0KFT. KXMR SOUNDING PROFILE SHOWS MID-
LEVEL TEMPERATURES (700/500MB, +9.0C/-7.8C) RESPECTIVELY WITH A
PRECIPITABLE WATER VALUE OF 2.07 INCHES.
AN INVERTED SURFACE TROUGH IS STILL DEPICTED IN THE EASTERN GULF AND
IS FORECAST TO PUSH VERY SLOWLY WESTWARD AWAY FROM THE FLORIDA
PENINSULA OVER THE NEXT 24 HOURS. THIS WILL ALLOW THE ATLANTIC RIDGE
TO GRADUALLY BUILD EASTWARD TOWARD ECFL. THE GFS POOLS DEEPER
PRECIPITABLE WATER VALUES ACROSS NORTH/NORTH CENTRAL FLORIDA UP TO
2.40 INCHES. MOISTURE VALUES TAPER DOWN THROUGH THE TREASURE COAST.
THE EAST COAST SEA BREEZE BOUNDARY WILL DEVELOP BY EARLY AFTERNOON
AND PUSH SLOWLY INLAND. EXPECT INITIAL SHOWERS/STORMS TO FORM ALONG
THIS BOUNDARY AND JUST INLAND WITH COVERAGE INCREASING THROUGH LATE
DAY AND INCREASING NORTH/WEST FROM THE TREASURE COAST. WILL KEEP 60
TO 70 PERCENT POPS ALONG THE I-4 CORRIDOR AND TAPER DOWN TO AROUND
40 TO 50 PERCENT ALONG THE IMMEDIATE MARTIN COUNTY COAST AND THIS
HERE COULD STILL BE A BIT HIGH. THE LOCAL HRRR MODEL ALSO SUGGESTS
STRONGER STORMS/HIGHER COVERAGE INLAND/NORTH TODAY WITH ADDITIONAL
BOUNDARY MERGERS AND DEEPER MOISTURE HERE.
HEAVY RAINFALL...FREQUENT LIGHTNING AND GUSTY WINDS TO AROUND 45 MPH
WILL CONTINUE AS THREATS. HEAVY RAINFALL COULD LEAD TO PONDING OF
WATER ON ROADWAYS AND NUISANCE FLOODING IN LOW-LYING AREAS AS WELL
AS ANYWHERE ELSE WHERE ABUNDANT RAINFALL HAS OCCURRED OVER RECENT
DAYS. CELL MOVEMENT WILL BE MAINLY FROM THE SOUTH TO THE NORTH AT
AROUND 20 MPH.
&&
.AVIATION...DEEP SOUTHERLY MOIST FLOW WITH NUMEROUS SHOWERS AND
SCATTERED STORMS THIS AFTERNOON/EARLY EVENING. VCTS MAINLY AFT 18Z
WITH ASSOC TEMPO GROUPS. TEMPO IFR/MVFR CIGS/VSBYS IN SCT-NMRS
CONVECTION. SEA BREEZE/MESOSCALE BOUNDARY COLLISIONS WILL AID TO
INCREASE COVERAGE LATE IN THE DAY. DIURNAL ACTIVITY WILL DECREASE IN
COVERAGE/INTENSITY THROUGH THE EVENING WITH MAINLY DRY CONDS
OVERNIGHT.
&&
.MARINE...TODAY-TONIGHT...CAUTIONARY STATEMENTS LIKELY TO BE DROPPED
FOR OFFSHORE ZONES FOR THE 10AM/14Z CWF ISSUANCE AS BOTH WINDS/SEAS
CONTINUE TO DECREASE/SUBSIDE. PERSISTENT LONG PERIOD SWELL CONTINUES
OVER THE WATERS. S/SSE WINDS DECREASING TO 10-15 KTS INTO THE
AFTERNOON AND AROUND 10 KTS OR LESS THROUGH THE EVENING/OVERNIGHT.
SEAS FALLING TO 3-5 FT THRU THE AFTN AND 3-4 FT TONIGHT.
THERE WILL BE A HIGHER COVERAGE OF STORMS NORTH OF THE CAPE WITH
LOWER (POSSIBLY MUCH LOWER) COVERAGE OVER THE TREASURE COAST WATERS.
STORM MOTION WILL BE OUT OF THE SOUTH TO SOUTH-SOUTHWEST SO SOME
STORMS NEAR THE COAST...ALONG THE EAST COAST SEA BREEZE...MAY PUSH
ACROSS INTRACOASTAL/NEAR SHORE ATLC WATERS THIS AFTERNOON/EARLY
EVENING.
&&
.HYDROLOGY...SHINGLE CREEK AT CAMPBELL (SHIF1) REMAINS WITHIN 0.78
FOOT OF FLOOD STAGE. FORTUNATELY LITTLE IF ANY RAINFALL OCCURRED
OVER THE BASIN OVERNIGHT BUT WILL NEED TO WATCH FOR PERSISTENT
RAINFALL OVER THE BASIN THIS AFTERNOON AND EARLY EVENING.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...FLOOD WATCH THROUGH THIS EVENING FOR COASTAL VOLUSIA COUNTY-
INDIAN RIVER-INLAND VOLUSIA COUNTY-MARTIN-NORTHERN BREVARD
COUNTY-NORTHERN LAKE COUNTY-OKEECHOBEE-ORANGE-OSCEOLA-
SEMINOLE-SOUTHERN BREVARD COUNTY-SOUTHERN LAKE COUNTY-ST.
LUCIE.
AM...NONE.
&&
$$
FORECASTS...SEDLOCK
IMPACT WEATHER...VOLKMER/LASCODY
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1100 AM CDT MON AUG 31 2015
.UPDATE...
ISSUED AT 1049 AM CDT MON AUG 31 2015
WEAK REMNANTS OF THE BOUNDARY IN THE REGION FROM YESTERDAY
PROVIDING JUST ENOUGH OF A FOCUS FOR SHOWERS AND THUNDERSTORMS
THIS MORNING. SOME INTENSE PRECIPITATION RATES COMBINED WITH
A LACK OF SIGNIFICANT STORM MOTION HAS RESULTED IN HIGH RAINFALL
TOTALS UNDER THE NEARLY STATIONARY STORMS. HAVE HAD TO SENT OUT
UPDATES FOR PRECIP IN THE SOUTHEAST. ENOUGH GAPS IN THE CLOUD
COVER OVER THE SE THAT NO RUSH TO KNOCK DOWN THE MAX TEMPS FOR
TODAY...BUT WILL KEEP AN EYE ON THE AREA. OTHERWISE, A WARM A
MUGGY DAY FOR CENTRAL ILLINOIS.
&&
.SHORT TERM...(TODAY)
ISSUED AT 317 AM CDT MON AUG 31 2015
08Z/3AM SURFACE ANALYSIS SHOWS DISSIPATING FRONTAL BOUNDARY
EXTENDING FROM NORTHERN INDIANA INTO CENTRAL ILLINOIS...GENERALLY
ALONG A FORT WAYNE TO QUINCY LINE. AS WAS THE CASE LAST
NIGHT...QUITE A BIT OF FOG IS DEVELOPING ALONG/NORTH OF THE BOUNDARY
WHERE WINDS ARE NEARLY CALM AND LOW-LEVEL MOISTURE IS ABUNDANT.
LATEST OBS SHOW LOWEST VISBYS CONCENTRATED ALONG THE SOUTHERN SHORE
OF LAKE MICHIGAN ACROSS NORTHERN INDIANA INTO THE CHICAGO AREA.
HRRR HAS BEEN CONSISTENTLY SPREADING THIS THICKER FOG W/SW ALONG THE
FRONT INTO THE NORTHERN KILX CWA OVER THE NEXT COUPLE HOURS...AND AM
BEGINNING TO SEE THIS UNFOLDING WITH VISBY NOW DOWN TO 1/4SM AS FAR
SW AS KIKK. FOLLOWING THE HRRR TREND...WILL MENTION AREAS OF DENSE
FOG ALONG/NORTHEAST OF A GALESBURG TO BLOOMINGTON-NORMAL LINE EARLY
THIS MORNING...WITH PATCHY/AREAS OF FOG ELSEWHERE AROUND THE AREA.
HIGH-RES MODELS SUCH AS THE HRRR AND RAPID REFRESH ARE SUGGESTING
THAT ISOLATED CONVECTION MAY DEVELOP ACROSS SOUTHEAST ILLINOIS OVER
THE NEXT COUPLE OF HOURS. LATEST RADAR IMAGERY IS CLEAR...HOWEVER
SCATTERED MID-LEVEL CLOUDS ARE BEGINNING TO DEVELOP ON IR SATELLITE
IMAGERY ALONG/SOUTH OF I-70...SO HAVE OPTED TO CARRY SLIGHT CHANCE
POPS HERE EARLY THIS MORNING. LATEST WATER VAPOR IMAGERY SHOWS A
SMALL BUT VIGOROUS SHORT-WAVE DROPPING SOUTHWESTWARD FROM NORTHEAST
INDIANA. THIS FEATURE WILL LIKELY INTERACT WITH THE DECAYING FRONT
TO TRIGGER ISOLATED CONVECTION FURTHER NORTH INTO THE CWA THIS
AFTERNOON. MOST MODELS ARE HINTING AT LEAST SOME QPF ACROSS THE
SOUTHERN TWO-THIRDS OF THE AREA...SO HAVE ADDED SLIGHT CHANCE POPS
ALONG/SOUTH OF A JACKSONVILLE TO BLOOMINGTON-NORMAL LINE FOR THE
AFTERNOON.
.LONG TERM...(TONIGHT THROUGH SUNDAY)
ISSUED AT 317 AM CDT MON AUG 31 2015
MAIN WEATHER STORY THROUGH THE EXTENDED WILL BE THE VERY WARM AND
HUMID CONDITIONS THAT ARE EXPECTED TO PERSIST THROUGH EARLY NEXT
WEEK. HIGH TEMPERATURES ON TUESDAY WILL REACH THE UPPER 80S TO
AROUND 90 DEGREES...THEN READINGS WILL CLIMB INTO THE LOWER 90S FOR
THE REMAINDER OF THE PERIOD. DRY WEATHER WILL GENERALLY BE THE
RULE...HOWEVER ISOLATED CONVECTION CANNOT BE RULED OUT...ESPECIALLY
TUESDAY AFTERNOON AS A WEAKNESS IN THE MEAN 500MB RIDGE AXIS REMAINS
IN THE VICINITY. MODELS ARE HINTING AT SOME QPF ACROSS THE E/NE CWA
AS THIS FEATURE GRADUALLY SHIFTS INTO THE GREAT LAKES BY WEDNESDAY.
THE NEXT SIGNIFICANT CHANCE FOR RAIN WILL NOT ARRIVE UNTIL EARLY
NEXT WEEK...WHEN A STRONG SHORT-WAVE FLATTENS THE UPPER RIDGE AND
PUSHES A COLD FRONT INTO THE REGION. MODELS ARE IN DISAGREEMENT
CONCERNING THE SPEED OF THIS PROCESS...WITH THE GFS BEING ABOUT 24
HOURS FASTER THAN THE ECMWF/GEM. THE 00Z AUG 31 GFS SHOWS THE COLD
FRONT PASSING THROUGH CENTRAL ILLINOIS LATE SUNDAY NIGHT INTO
MONDAY...WHILE THE ECMWF/GEM HAVE DELAYED FROPA UNTIL LATE MONDAY
NIGHT INTO TUESDAY. GIVEN PERSISTENT AND HIGHLY AMPLIFIED RIDGE
POSITIONED ACROSS THE MIDWEST...THINK A SLOWER BREAK DOWN TO THE
PATTERN IS PRUDENT. HAVE THEREFORE TRENDED THE FORECAST TOWARD THE
SLOWER ECMWF/GEM CONSENSUS. AS A RESULT...AM EXPECTING DRY
CONDITIONS THROUGH SUNDAY NIGHT...WITH HIGHER RAIN CHANCES ARRIVING
BY LATE MONDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 653 AM CDT MON AUG 31 2015
ASIDE FROM SOME EARLY MORNING IFR/MVFR FOG TODAY AND AGAIN LATE
TONIGHT, PREDOMINANTLY VFR CONDITIONS EXPECTED ACROSS THE CENTRAL
ILLINOIS TERMINALS THROUGH THE 12Z TAF VALID TIME. DIURNALLY
DRIVEN CU WILL POP THIS MORNING, WITH ISOLATED SHOWER/STORMS
POSSIBLY DEVELOPING. HOWEVER, SHOWER/STORM COVERAGE IS EXPECTED TO
BE TOO LOW TO MENTION AT THIS TIME. WINDS SHOULD CONTINUE TO BE
LIGHT OVERALL.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HJS
SHORT TERM...BARNES
LONG TERM...BARNES
AVIATION...BAK
AREA FORECAST DISCUSSION
NWS LINCOLN IL
659 AM CDT MON AUG 31 2015
.SHORT TERM...(TODAY)
ISSUED AT 317 AM CDT MON AUG 31 2015
08Z/3AM SURFACE ANALYSIS SHOWS DISSIPATING FRONTAL BOUNDARY
EXTENDING FROM NORTHERN INDIANA INTO CENTRAL ILLINOIS...GENERALLY
ALONG A FORT WAYNE TO QUINCY LINE. AS WAS THE CASE LAST
NIGHT...QUITE A BIT OF FOG IS DEVELOPING ALONG/NORTH OF THE BOUNDARY
WHERE WINDS ARE NEARLY CALM AND LOW-LEVEL MOISTURE IS ABUNDANT.
LATEST OBS SHOW LOWEST VISBYS CONCENTRATED ALONG THE SOUTHERN SHORE
OF LAKE MICHIGAN ACROSS NORTHERN INDIANA INTO THE CHICAGO AREA.
HRRR HAS BEEN CONSISTENTLY SPREADING THIS THICKER FOG W/SW ALONG THE
FRONT INTO THE NORTHERN KILX CWA OVER THE NEXT COUPLE HOURS...AND AM
BEGINNING TO SEE THIS UNFOLDING WITH VISBY NOW DOWN TO 1/4SM AS FAR
SW AS KIKK. FOLLOWING THE HRRR TREND...WILL MENTION AREAS OF DENSE
FOG ALONG/NORTHEAST OF A GALESBURG TO BLOOMINGTON-NORMAL LINE EARLY
THIS MORNING...WITH PATCHY/AREAS OF FOG ELSEWHERE AROUND THE AREA.
HIGH-RES MODELS SUCH AS THE HRRR AND RAPID REFRESH ARE SUGGESTING
THAT ISOLATED CONVECTION MAY DEVELOP ACROSS SOUTHEAST ILLINOIS OVER
THE NEXT COUPLE OF HOURS. LATEST RADAR IMAGERY IS CLEAR...HOWEVER
SCATTERED MID-LEVEL CLOUDS ARE BEGINNING TO DEVELOP ON IR SATELLITE
IMAGERY ALONG/SOUTH OF I-70...SO HAVE OPTED TO CARRY SLIGHT CHANCE
POPS HERE EARLY THIS MORNING. LATEST WATER VAPOR IMAGERY SHOWS A
SMALL BUT VIGOROUS SHORT-WAVE DROPPING SOUTHWESTWARD FROM NORTHEAST
INDIANA. THIS FEATURE WILL LIKELY INTERACT WITH THE DECAYING FRONT
TO TRIGGER ISOLATED CONVECTION FURTHER NORTH INTO THE CWA THIS
AFTERNOON. MOST MODELS ARE HINTING AT LEAST SOME QPF ACROSS THE
SOUTHERN TWO-THIRDS OF THE AREA...SO HAVE ADDED SLIGHT CHANCE POPS
ALONG/SOUTH OF A JACKSONVILLE TO BLOOMINGTON-NORMAL LINE FOR THE
AFTERNOON.
.LONG TERM...(TONIGHT THROUGH SUNDAY)
ISSUED AT 317 AM CDT MON AUG 31 2015
MAIN WEATHER STORY THROUGH THE EXTENDED WILL BE THE VERY WARM AND
HUMID CONDITIONS THAT ARE EXPECTED TO PERSIST THROUGH EARLY NEXT
WEEK. HIGH TEMPERATURES ON TUESDAY WILL REACH THE UPPER 80S TO
AROUND 90 DEGREES...THEN READINGS WILL CLIMB INTO THE LOWER 90S FOR
THE REMAINDER OF THE PERIOD. DRY WEATHER WILL GENERALLY BE THE
RULE...HOWEVER ISOLATED CONVECTION CANNOT BE RULED OUT...ESPECIALLY
TUESDAY AFTERNOON AS A WEAKNESS IN THE MEAN 500MB RIDGE AXIS REMAINS
IN THE VICINITY. MODELS ARE HINTING AT SOME QPF ACROSS THE E/NE CWA
AS THIS FEATURE GRADUALLY SHIFTS INTO THE GREAT LAKES BY WEDNESDAY.
THE NEXT SIGNIFICANT CHANCE FOR RAIN WILL NOT ARRIVE UNTIL EARLY
NEXT WEEK...WHEN A STRONG SHORT-WAVE FLATTENS THE UPPER RIDGE AND
PUSHES A COLD FRONT INTO THE REGION. MODELS ARE IN DISAGREEMENT
CONCERNING THE SPEED OF THIS PROCESS...WITH THE GFS BEING ABOUT 24
HOURS FASTER THAN THE ECMWF/GEM. THE 00Z AUG 31 GFS SHOWS THE COLD
FRONT PASSING THROUGH CENTRAL ILLINOIS LATE SUNDAY NIGHT INTO
MONDAY...WHILE THE ECMWF/GEM HAVE DELAYED FROPA UNTIL LATE MONDAY
NIGHT INTO TUESDAY. GIVEN PERSISTENT AND HIGHLY AMPLIFIED RIDGE
POSITIONED ACROSS THE MIDWEST...THINK A SLOWER BREAK DOWN TO THE
PATTERN IS PRUDENT. HAVE THEREFORE TRENDED THE FORECAST TOWARD THE
SLOWER ECMWF/GEM CONSENSUS. AS A RESULT...AM EXPECTING DRY
CONDITIONS THROUGH SUNDAY NIGHT...WITH HIGHER RAIN CHANCES ARRIVING
BY LATE MONDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 653 AM CDT MON AUG 31 2015
ASIDE FROM SOME EARLY MORNING IFR/MVFR FOG TODAY AND AGAIN LATE
TONIGHT, PREDOMINANTLY VFR CONDITIONS EXPECTED ACROSS THE CENTRAL
ILLINOIS TERMINALS THROUGH THE 12Z TAF VALID TIME. DIURNALLY
DRIVEN CU WILL POP THIS MORNING, WITH ISOLATED SHOWER/STORMS
POSSIBLY DEVELOPING. HOWEVER, SHOWER/STORM COVERAGE IS EXPECTED TO
BE TOO LOW TO MENTION AT THIS TIME. WINDS SHOULD CONTINUE TO BE
LIGHT OVERALL.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BARNES
LONG TERM...BARNES
AVIATION...BAK
AREA FORECAST DISCUSSION
NWS DES MOINES IA
647 AM CDT MON AUG 31 2015
.UPDATE...
ISSUED AT 646 AM CDT MON AUG 31 2015
VISIBILITIES NEVER DETERIORATED AS EXPECTED OVER MUCH OF SOUTHERN
AND EAST CENTRAL IOWA...ONLY DOWN TO A FEW MILES AT WORST...SO THE
PREVIOUS ADVISORY HAS BEEN CANCELLED. LOW VISIBILITIES DO CONTINUE
IN AREAS OVER THE NORTHERN HALF OF IOWA HOWEVER...BUT THEY ARE
EXPECTED TO IMPROVE SHORTLY.
&&
.SHORT TERM /TODAY/...
ISSUED AT 320 AM CDT MON AUG 31 2015
MUCH LIKE YESTERDAY...THE MAIN CONCERNS ARE TEMP AND VISIBILITY
TRENDS. STRATUS COVERAGE IS LESS THAN LAST NIGHT WITH ONLY SOME
TOKEN CIRRUS NW. THIS WOULD SUGGEST A MORE UNIFORM RADIATION FOG
DEVELOPMENT BUT THAT HAS NOT BEEN THE CASE WITH VISIBILITIES
SOMEWHAT VARIABLE. EVEN THOUGH SRN IA WAS HIT HARDEST WITH DENSE FOG
LAST NIGHT AND CONDITIONS ARE SIMILAR...VISIBILITIES HAVE NOT REALLY
DROPPED MUCH IN THE ADVISORY AREA. RAP 1000-950MB RH IS ACTUALLY
RELATIVELY LOWER IN THIS AREA SO ADVISORY CONFIDENCE IS NOT GREAT.
HOWEVER CONFIDENCE IS EQUALLY NOT GREAT THAT CONDITIONS WILL NOT
TANK IN THE NEXT SEVERAL HOURS EITHER SO WILL LEAVE HEADLINE AS IS
AND EVALUATE HOURLY FOR NEEDED CHANGES. LOWEST VISIBILITIES ARE
ACTUALLY NORTH SO WILL GO WITH KEEPING HEADLINE AND SPS OTHER AREAS
FOR NOW.
TEMPS WILL BE PROBLEMATIC ONCE AGAIN. MODEL SOUNDINGS ARE SOMEWHAT
MORE AGGRESSIVE WITH MIXING POTENTIAL...WHICH MAKES SOME SENSE WITH
WINDS A TAD HIGHER AND LESS STRATUS AROUND. HOWEVER IS HAS BEEN
DIFFICULT WARMING TOO MUCH OVER THE PAST FEW WEEKS...ESPECIALLY TO
GFS EXPECTATIONS WHICH HAS SHOWN AND WARM BIAS. COOLER NAM MOS HAS
BEEN BETTER RECENTLY AND WILL CONTINUE TO FOLLOW THAT LEAD. THIS
RESULTS IN TRIMMING PREVIOUS FORECAST SEVERAL DEGREES.
.LONG TERM /TONIGHT THROUGH SUNDAY/...
ISSUED AT 320 AM CDT MON AUG 31 2015
THE FORECAST FOR THIS WEEK REMAINS WARM AND MOSTLY DRY. A DEEP
LAYER RIDGE BLANKETING THE SOUTHERN U.S. WILL GRADUALLY PIVOT
AROUND OVER THE EASTERN U.S. AS A LONGWAVE TROUGH STEADILY DIGS
DOWN THE WEST COAST. THIS WILL PLACE IOWA BENEATH THE PROVERBIAL
RING OF FIRE FOR SEVERAL DAYS THIS WEEK...HOWEVER...THE SUBTLE
SHORTWAVES MOVING THROUGH THE STEERING FLOW ALOFT WILL BE FAIRLY
WEAK AND DIFFICULT TO PIN DOWN IN TERMS OF TIMING. WILL MAINTAIN
LOW 20 TO 30 POPS AT TIMES DURING THE WORK WEEK...MAINLY ACROSS
THE NORTHWEST HALF OF THE FORECAST AREA...BUT ANY STORMS SHOULD BE
OF LITTLE IMPACT. MEANWHILE TEMPERATURES WILL CLIMB WELL INTO THE
80S EACH DAY GIVEN THE WARM TEMPERATURES ALOFT...MODEST SOUTH TO
SOUTHWEST LOW LEVEL FLOW...AND MOSTLY SUNNY SKIES FORECAST.
LATER IN THE WEEK...FROM ABOUT THURSDAY THROUGH SATURDAY...THE
DEEPENING WESTERN TROUGH WILL SHUNT THE LARGE SOUTHERN RIDGE OVER
TOWARD THE APPALACHIANS AND RESULT IN ANY SUBTLE SHORTWAVES
EJECTING OUT OF THE TROUGH MOVING MORE NORTHEASTWARD ACROSS THE
HIGH PLAINS AND MINNESOTA. THIS RESULTS IN A PERIOD OF LOWER POPS
BUT SLIGHTLY HIGHER TEMPERATURES AS ANY STORMS THAT FORM SHOULD
RANGE FROM NEBRASKA UP ACROSS THE DAKOTAS AND THE WARM AIRMASS TO
OUR SOUTHEAST WILL ENCROACH A BIT MORE INTO IOWA BY THE END OF THE
WEEK. THE WEST COAST TROUGH WILL EVENTUALLY KICK OUT ACROSS THE
CENTRAL U.S. AND PUSH A COLD FRONT ACROSS OUR REGION...GENERATING
MORE WIDESPREAD SHOWERS AND THUNDERSTORMS FOLLOWED BY COOLER
WEATHER. HOWEVER...THERE CONTINUES TO BE A CONSIDERABLE AMOUNT OF
SPREAD AMONG THE LONG RANGE MODELS IN THEIR SOLUTIONS FOR THIS
EVOLUTION AND PARTICULARLY THE TIMING OF RAIN AND FRONTAL PASSAGE
FOR IOWA. HAVE THUS STUCK CLOSE TO MODEL CONSENSUS WITH RAIN
CHANCES MOSTLY IN THE SUNDAY/SUNDAY NIGHT TIME FRAMES AND COOLER
WEATHER LIKELY BY NEXT MONDAY. THESE DETAILS WILL GRADUALLY COME
INTO FOCUS LATER THIS WEEK.
&&
.AVIATION...31/12Z
ISSUED AT 646 AM CDT MON AUG 31 2015
FOG TRENDS REMAIN THE PRIMARY CONCERN EARLY THIS MORNING.
CONDITIONS VARY WIDELY AT TAF SITES FROM LIFR /KMCW/ TO VFR /KDSM/
BUT ALL SITES SHOULD CONTINUE TO IMPROVE THROUGH 15Z. ALTHOUGH
SOME SCT/BKN CU MAY DEVELOP DURING PEAK HEATING OF THE DAY...THEY
SHOULD BE ABOVE 3K FT WITH VFR ANTICIPATED THROUGH THE AFTERNOON
AND EVENING. SOME PATCHY MVFR RADIATION FOG MAY DEVELOP AGAIN INTO
EARLY TUE MORNING...BUT NOT TO THE EXTENT SEEN THE PAST FEW
MORNINGS.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...SMALL
SHORT TERM...SMALL
LONG TERM...LEE
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1159 AM EDT MON AUG 31 2015
...FORECAST UPDATE...
ISSUED AT 1155 AM EDT MON AUG 31 2015
GOES SOUNDER DATA INDICATE PRECIPITABLE WATER LEVELS ARE AROUND 1.3
INCHES...QUITE A BIT LESS THAN THIS TIME YESTERDAY. AMDAR SOUNDINGS
SHOW A PRETTY GOOD CAP AT 500 MB. LATEST RUC SOUNDINGS SHOW MORE PW
THAN WHAT THE GOES SOUNDER HAS. WITH THE DRYING OUT...MULTIPLE
MODELS SHOW LITTLE IN THE WAY OF PRECIP. DECIDED TO BACK OFF ON POPS
FOR ALL BUT OUR NORTHERN STRIPE OF COUNTIES IN INDIANA. REST OF THE
FORECAST LOOKS GOOD WITH LOUISVILLE METRO GETTING TO THE UPPER 80S
AND THE REST OF THE AREA IN THE MID 80S.
.SHORT TERM (NOW THROUGH TUESDAY)...
ISSUED AT 315 AM EDT MON AUG 31 2015
EARLY THIS MORNING SOME PATCHY FOG HAS DEVELOPED IN SPOTS. THINK WE
MAY SEE MORE DEVELOP ESPECIALLY IN AREAS THAT RECEIVED RAINFALL
YESTERDAY, SO WILL CONTINUE EARLY MORNING PATCHY FOG MENTION BUT
DON`T THINK FOG SHOULD BECOME DENSE OR WIDESPREAD. FOG SHOULD
DIMINISH SHORTLY AFTER SUNRISE.
FOR THE REST OF THE DAY, EXPECT PARTLY CLOUDY SKIES WITH ISOLATED
AFTERNOON/EVENING SHOWERS/STORMS DEVELOPING AGAIN. RIDGING WILL BE
ON THE INCREASE TODAY AND INHIBIT CONVECTION COVERAGE A LITTLE MORE
THAN YESTERDAY. THE MOST LIKELY LOCATIONS TO SEE AN ISLD SHOWER OR
STORM LOOK TO BE SOUTHERN INDIANA OR NORTH CENTRAL KY WHERE CAPPING
MAY BE WEAKER. EXPECT HIGH TEMPS TO BE SIMILAR TO YESTERDAY IN THE
MIDDLE 80S.
TONIGHT IS EXPECTED TO BE MAINLY DRY WITH ANY CONVECTION ENDING
DURING THE EVENING HOURS. RIDGING WILL CONTINUE TO INCREASE OVER
THE REGION WITH A GOOD MID LEVEL CAP NOTED IN SOUNDINGS FOR TUESDAY.
THEREFORE WILL KEEP TUES DRY. LOWS TONIGHT SHOULD RANGE FROM THE
MID 60S TO AROUND 70. HIGHS ON TUES WILL WARM INTO THE UPPER 80S TO
AROUND 90.
.LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)...
ISSUED AT 258 AM EDT MON AUG 31 2015
THE MAIN STORY FOR THE LONG TERM PERIOD IS THE LIKELY HOT AND DRY
CONDITIONS AS WE HEAD INTO THE FIRST FULL WEEK OF SEPTEMBER AND THE
UPCOMING HOLIDAY WEEKEND.
THE 31.00Z GUIDANCE TRENDED TOWARD SIMILAR SOLUTIONS WITH REGARD TO
THE UPPER LEVEL PATTERN...SHOWING BUILDING HEIGHTS AND RIDGING
WEDNESDAY THROUGH THIS UPCOMING WEEKEND. AT THE SURFACE...THE REGION
WILL BE MOSTLY UNDER THE INFLUENCE OF HIGH PRESSURE.
SENSIBLE WEATHER INCLUDES SEASONABLY WARM TO HOT CONDITIONS AS
READINGS TOP OUT IN THE UPPER 80S TO LOW 90S EACH AFTERNOON. LOOKING
AT SOME OF THE EXTENDED ENSEMBLE MOS DATA...THURSDAY THROUGH
SATURDAY LOOK TO BE THE WARMEST...AND A FEW MID 90 READINGS ARE
POSSIBLE IN THE TYPICAL WARM SPOTS AND URBAN CORES THOSE DAYS. PLAN
ON MILD TO MUGGY MORNINGS WITH READINGS IN THE UPPER 60S TO LOW 70S.
A WEAK CAP AND SUBSIDENCE ALOFT SHOULD PRECLUDE THE DEVELOPMENT OF
AFTERNOON/EVENING SHOWERS FOR THE MAJORITY OF FOLKS MOST
DAYS...HOWEVER GIVEN THE WARM TEMPERATURES AND MODEST DEWPOINTS
/MID 60S/...COULDN`T RULE OUT A STRAY SHOWER OR STORM. FOR
CONTINUITY...KEPT A VERY SLIGHT CHANCE IN THE FORECAST FOR SOUTHERN
INDIANA AND NORTHERN KENTUCKY WEDNESDAY. BY THIS WEEKEND...A MODEL
CONSENSUS SHOWS SLIGHT CHANCES OF SHOWER/STORMS...THOUGH WITH NO
REAL FORCING MECHANISM OR STRONG MOISTURE TRANSPORT THIS MAY BE
OVERDONE. A CONTINUATION OF DRY WEATHER COULD CONTINUE THROUGH
SUNDAY.
&&
.AVIATION (12Z TAF UPDATE)...
ISSUED AT 645 AM EDT MON AUG 31 2015
SOME LIGHT BR AT BWG WILL BE THE MAIN TAF CONCERN. WITH LIGHT WINDS
AND DECENT LOW LEVEL MOISTURE BWG HAS DIPPED INTO THE IFR CAT AND
MAY CONTINUE TO DO SO FOR THE NEXT HOUR OR TWO. WINDS WILL BECOME
SWW DURING THE DAYLIGHT HOURS WITH SOME AFTERNOON CU EXPECTED. A
STRAY SHOWER/STORM CANNOT BE RULED OUT THIS AFTERNOON/EVENING BUT
FEEL THAT CHANCES ARE TOO SLIM TO INCLUDE IN THE TAFS. SKIES WILL
BECOME MOSTLY CLEAR FOR TONIGHT WITH LIGHT AND VRB WINDS.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
UPDATE.........RJS
SHORT TERM.....AMS
LONG TERM......ZBT
AVIATION.......AMS
AREA FORECAST DISCUSSION
NWS DULUTH MN
915 AM CDT MON AUG 31 2015
.UPDATE...
ISSUED AT 915 AM CDT MON AUG 31 2015
A COLD FRONT WAS DRAPED OVER EASTERN ND AND THE EXTREME CORNER OF NW
MN AT 14Z. THUNDERSTORMS WERE OCCURRING BEHIND THE FRONT IN NE ND
AND LIFTING NEWD INTO CANADA. SOUTHERLY FLOW OVER THE FORECAST
AREA HAS LED TO A STRATUS DECK OVER NW WI AND ADJACENT MN AND
ALONG THE NORTH SHORE OF LAKE SUPERIOR WITH SOME FOG THAT WAS
SLOWLY LIFTING. EXPECT THE STRATUS AND FOG TO CONTINUE TO ERODE
THIS MORNING AND HAVE ADJUSTED FOR THIS TREND. WITH THE STORMS
MOVING INTO CANADA AND LATEST HRRR INDICATING NO STORMS INTO THE
REGION THROUGH THE AFTERNOON FOR THE LAST FEW RUNS. HAVE REMOVED
THE MENTION OF STORMS TODAY.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 240 AM CDT MON AUG 31 2015
AN UPPER RIDGE WILL MOVE EAST OF THE REGION TODAY WITH SOUTHERLY
SURFACE FLOW KEEPING HIGHER DEWPOINTS IN PLACE. A COLD FRONT WILL
MOVE INTO FAR WESTERN MINNESOTA BY LATE AFTERNOON/EARLY EVENING
AND PROGRESS INTO NORTHEAST MINNESOTA TONIGHT BEFORE WEAKENING
TUESDAY.
STRATUS AND SOME PATCHY FOG HAVE ONCE AGAIN FORMED ACROSS
NORTHERN WISCONSIN AND PORTIONS OF NORTHEAST MINNESOTA THIS
MORNING. THE STRATUS/FOG SHOULD BURN OFF THIS MORNING AND THE RAP
SEEMS TO BE HANDLING THIS DECENTLY. CLOUDS WILL DIMINISH THROUGH
THE MORNING...THEN INCREASE AGAIN OVER WESTERN AREAS THIS
AFTERNOON AHEAD OF THE COLD FRONT. WE KEPT A MENTION OF
SHOWERS/STORMS IN THE WEST LATE TODAY...THEN PROGRESS THE CHANCE
EAST TONIGHT. THE NAM/GFS/ECMWF ALONG WITH THE HIGHER RESOLUTION
CAMS SUGGEST COVERAGE WILL BE LIMITED SO WE ONLY HAVE LOW POPS AT
THIS TIME. WE EXPECT HIGHS ABOVE NORMAL AGAIN TODAY...BUT DID
LOWER A BIT IN SPOTS DUE TO THE STRATUS IN PLACE EARLY. WE HAVE
HIGHS FROM AROUND 80 TO 85 FOR MOST AREAS.
THE FRONT WILL WEAKEN TUESDAY...BUT MAY STILL BE STRONG ENOUGH TO
FORCE A FEW SHOWERS/STORMS OVER PORTIONS OF NORTHWEST WISCONSIN
WHERE WE KEPT SOME POPS INTO THE AFTERNOON AND OVER FAR EASTERN
MINNESOTA IN THE MORNING. THERE MAY AGAIN BE SOME STRATUS/FOG THAT
FORM TONIGHT. HIGHS TUESDAY WILL AGAIN BE FROM 80 TO 85 FOR MOST
AREAS.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 240 AM CDT MON AUG 31 2015
WARM AND HUMID THROUGH THE REST OF THE WORK WEEK WITH OCCASIONAL
CHANCES FOR STORMS. THIS WEEKEND A STRONGER UPPER-LEVEL SYSTEM
COMBINED WITH A COLD FRONT MOVING IN FROM THE WEST WILL LEAD TO
BETTER CHANCES FOR WIDESPREAD SHOWERS AND STORMS OVER THE
WEEKEND...WITH MORE SEASONABLE TEMPERATURES BEHIND THE FRONT.
WED/THURS/FRI...FEELING LIKE MID-SUMMER WITH TEMPERATURES ABOVE
NORMAL...DEW POINTS IN THE MID 60S TO NEAR 70...AND CHANCES FOR
STORMS INCREASING TOWARDS THE WEEKEND. THIS PATTERN WILL BE DUE TO A
LONGWAVE TROUGH DEVELOPING IN THE WEST AND A WEAK RIDGE OVER THE
EASTERN THIRD OF THE COUNTRY...A PATTERN WHICH GENERALLY PERSISTS
MID TO LATE WEEK. WITH A WARM FRONT LIFTING NORTH WEDNESDAY WINDS
WILL BE BREEZY WEDNESDAY AND WINDY THURSDAY...GUSTS UP TO 30 MPH
POSSIBLE THURSDAY. WHILE THERE WILL BE A SLIGHT CHANCE FOR ISOLATED
STORMS WED AND THURS...THE BETTER CHANCES FOR STORMS COME FRIDAY
WHEN A MID-LEVEL SHORTWAVE TROUGH LIFTS THROUGH THE CENTRAL/NORTHERN
PLAINS INTO THE UPPER MIDWEST. PLENTY OF ELEVATED INSTABILITY AND
INCREASING UPPER LEVEL WINDS COULD SUSTAIN A FEW STRONG STORMS...BUT
IN GENERAL DO NOT EXPECT SEVERE THUNDERSTORMS. HIGHS IN THE LOW 80S.
SAT/SUN...A MUCH MORE ACTIVE PERIOD WITH A COLD FRONT EVENTUALLY
SWEEPING ACROSS THE UPPER MIDWEST...WITH MUCH COOLER TEMPERATURES
BEHIND THE FRONT ON TAP FOR NEXT WEEK. GFS IS A VERY WET OUTLIER
WITH FRONTAL PASSAGE QUICKER THAN OTHER GUIDANCE...WITH THE GEFS
ENSEMBLE MEMBERS DEPICTING A WIDE RANGE OF TIMING POSSIBILITIES.
THERE IS POTENTIAL FOR SOME STRONG TO SEVERE STORMS GIVEN STRONGER
WINDS ALOFT...BUT WILL CONTINUE TO HOLD OFF MENTIONING THIS
POSSIBILITY IN THE HWO DUE TO LOW CONFIDENCE WITH REGARDS TO IF THE
RIGHT CONDITIONS WILL DEVELOP. HIGH FREEZING LEVELS /12-14 KFT/ MAY
LIMIT POTENTIAL FOR LARGE HAIL...AND FAIRLY SATURATED MODEL
SOUNDINGS INDICATE MORE OF A HEAVY RAIN THREAT. GFS DEPICTS A SWATH
OF 2+ INCH RAINFALL OVER NORTHEAST MINNESOTA FOR SATURDAY AFTERNOON
WHICH SEEMS LIKE AN OUTLIER COMPARED TO THE GEFS ENSEMBLE MEAN OF 3-
4 TENTHS OF AN INCH. GEFS NARR-REFORECAST-CALIBRATED PRECIP
PROBABILITIES FROM ESRL/PSD...A METHOD OF TRYING TO CALIBRATE THE
GEFS FORECASTS TO PAST EVENTS TO PRODUCE A MORE RELIABLE FORECAST
THAN THE RAW GEFS PROBABILITIES...INDICATE ONLY A 10-20 PERCENT
CHANCE FOR 1"+ PRECIP OVER ANY 12-HOUR PERIOD THIS WEEKEND...SO
THERE IS LITTLE SUPPORT FOR THE DETERMINISTIC GFS FROM ITS ENSEMBLE
AND THEREFORE AM TREATING IT MORE AS AN INTERESTING OUTLIER THAN A
LIKELY SCENARIO. TEMPS WILL BE COOLER BEHIND THE FRONT...WHICH WILL
PROBABLY BE ON SUNDAY GIVEN THE ECMWF SLOWER TIMING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 653 AM CDT MON AUG 31 2015
ANOTHER MORNING WITH LIFR/IFR CEILINGS ACROSS THE
REGION...CONDITIONS WHICH SHOULD IMPROVE BY MID-MORNING. THIS
AFTERNOON WILL BE VFR WITH BREEZY WINDS OUT OF THE SOUTH...WINDS
STRONGEST AT BRD WHERE PEAK GUSTS TO AROUND 30 MPH ARE POSSIBLE.
THIS EVENING A WEAK FRONT WILL MOVE EAST ACROSS NORTHEAST
MINNESOTA WITH THE POTENTIAL FOR ISOLATED SHOWER/STORMS. CHANCES
ARE LOW...AND ONLY FELT CONFIDENT ENOUGH AT HIB TO INTRODUCE A
VCTS GROUP FOR THE EARLY EVENING. TONIGHT ANOTHER ROUND OF AT
LEAST MVFR VISIBILITY/CEILINGS ARE POSSIBLE AT DLH/HIB/HYR...BUT
THIS WILL BE DEPENDENT ON IF PRECIPITATION DEVELOPS AND HOW
WIDESPREAD IT BECOMES. INCLUDING A BEST GUESS IN THE TAFS ASSUMING
CONVECTION WILL BE ISOLATED IN NATURE AT BEST.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 81 65 84 63 / 0 30 20 10
INL 85 54 82 56 / 10 30 10 30
BRD 83 63 85 66 / 0 20 10 10
HYR 81 66 84 63 / 0 20 20 10
ASX 83 65 82 61 / 0 20 20 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
UPDATE...GSF
SHORT TERM...MELDE
LONG TERM...JJM
AVIATION...JJM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
935 AM EDT MON AUG 31 2015
.SYNOPSIS...AN UPPER LEVEL LOW WILL MOVE NORTHEASTWARD AWAY FROM THE
AREA LATE THIS MORNING...AS A WEAK SURFACE TROUGH PUSHES TOWARD THE
COAST. ASIDE FROM A WEAK WAVE APPROACHING FROM THE OHIO VALLEY
MIDWEEK...GENERAL HIGH PRESSURE WILL RESIDE OVER THE AREA AS DEEP
MOISTURE IS SHUNTED TO OUR SOUTH.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 935 AM MONDAY...
EARLIER UPDATE TARGETED THE CENTRAL/ERN CWA WITH HIGHEST POPS
(LIKELY TO CATEGORICAL) FOR THE ONGOING TROPICAL RAINFALL. THESE HIGH
POPS WILL SHIFT SLOWLY EASTWARD OVER THE NEXT SEVERAL HOURS AS THE
UPPER LEVEL LOW THAT CROSSED THE STATE EARLIER THIS MORNING HEADS
NNE INTO VA. RAIN RATES OF 1-2 INCHES PER HOUR HAVE BEEN COMMON...
ENOUGH TO PRODUCE SOME MINOR URBAN AND STREET FLOODING AND RISING
CREEKS BUT UNDER FLOODING THRESHOLDS... AND THIS RAIN SHOULD
ACTUALLY BE BENEFICIAL FOR MOST. WATER VAPOR IMAGERY SHOWS DRYING
OVER THE WRN CWA... SO WHILE A FEW WRAPAROUND SHOWERS ARE POSSIBLE
IN AREAS NW OF THE TRIANGLE... THESE SHOULD GENERATE LITTLE
ADDITIONAL RAINFALL. EASTERN SECTIONS ESPECIALLY ALONG AND EAST OF I-
95 MAY SEE A SLOWER TAPERING OF THE WIDESPREAD MODERATE RAIN...
GIVEN THAT ANOTHER WAVE NOW APPROACHING SAVANNAH GA WILL BE TRACKING
TO THE N OR NNE... SLOWING THE ARRIVAL OF DRIER AIR... AND THIS
TREND IS NOTED WELL IN THE RECENT RAP RUNS. POPS WILL START OUT
RANGING FROM ISOLATED AT MOST WEST TO CATEGORICAL EAST... TRENDING
DOWNWARD WEST TO EAST THROUGH THE REST OF THE DAY. ANY INSTABILITY
SHOULD BE MARGINAL... WITH MUCAPE MOSTLY HOLDING AT OR BELOW 1000
J/KG... SO WILL KEEP ANY THUNDER MENTION AT ISOLATED TO SCATTERED AT
MOST. TEMPS ARE A TOUGH CALL GIVEN THE GREATLY LIMITED INSOLATION IN
THE EAST... SO EXPECT HIGHS IN THE LOW-MID 80S WEST AND NEAR 80 TO
LOWER 80S EAST... WITH THESE EASTERN HIGHS NOT BEING REACHED UNTIL
VERY LATE IN THE DAY. -GIH
LOWS TONIGHT IN THE UPPER 60S TO LOWER 70S.
&&
.SHORT TERM /TUESDAY AND TUESDAY NIGHT/...
AS OF 345 AM MONDAY...
A WEAK/NONDESCRIPT SFC PATTERN WILL EXTEND ACROSS THE AREA ON
TUESDAY WITH HEIGHTS ALOFT BUILDING OVER THE SOUTHEAST AS THE
SUBTROPICAL RIDGE OVER THE SOUTHWEST ATLANTIC RETROGRADES WESTWARD.
OTHER THAN DAYTIME HEATING ATOP A SEASONABLY MOIST AIRMASS...
FORCING MECHANISM IS LACKING WITH ISOLATED DIURNAL CONVECTION AT
BEST.
HIGHS IN THE UPPER 80S TO LOWER 90S. LOWS IN THE UPPER 60S TO LOWER
70S.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 310 AM MONDAY...
MEDIUM RANGE MODELS ARE IN GENERAL AGREEMENT IN SHOWING A WEAK
DISTURBANCE ALOFT TRACKING FROM THE OHIO VALLEY MIDWEEK TO ACROSS
CENTRAL NC THURSDAY OR THURSDAY NIGHT. HOWEVER... THE LATEST GFS AND
ECMWF CONTINUE TO DISAGREE WRT WHAT HAPPENS TO IT. THE LATEST ECMWF
CONTINUES TO SHOW THE S/W SHIFTING TO THE EAST/SOUTHEAST AND
OFFSHORE BY THURSDAY AFTERNOON... WITH BRIEF S/W RIDGING BUILDING
OVER THE AREA BEFORE A WEAK MID LEVEL LOW LIFTS NORTHEASTWARD OUT OF
THE NORTHWEST GULF OF MEXICO AND INTO THE CAROLINAS BY FRIDAY NIGHT
AND LINGERING THROUGH THE END OF THE FORECAST PERIOD. MEANWHILE...
THE LATEST GFS IS SLOWER MOVING THE INITIAL S/W DISTURBANCE THROUGH
THE AREA ON THURSDAY... LINGERING INTO FRIDAY MORNING. THE S/W IS
THEN EXPECTED TO CLOSE OFF INTO A MID LEVEL LOW AND CONTINUE TO
SLOWLY SINK SOUTHWARD AS A STRONG 595 DECAMETER HIGH BEGINS TO BUILD
SOUTHWARD TOWARDS CENTRAL NC. GIVEN THIS PATTERN... THE LOW IN THE
NORTHWESTERN GULF OF MEXICO ACTUALLY SINKS FURTHER SOUTH AND NOT IN
THE DIRECTION OF CENTRAL. AT THE SURFACE... WE SHOULD SEE SOME TYPE
OF WEAK SURFACE TROUGH TRACK ACROSS THE AREA WITH THE INITIAL S/W
DISTURBANCE... WITH SURFACE HIGH PRESSURE BUILDING/EXTENDING INTO
CENTRAL NC FROM THE NORTH/NORTHEAST DURING THE WEEKEND. THUS... AT
THIS TIME... WILL KEEP POPS GENERALLY LOW... SLIGHT CHANCE TO LOW
END CHANCE DURING THE MEDIUM RANGE... GIVEN THE UNCERTAINTY IN WHAT
WILL GENERALLY BE MEAN RIDING OVER THE EASTERN HALF OF THE COUNTRY
DURING THIS TIME (WITH THE EMBEDDED DISTURBANCES/WEAK CLOSED LOWS).
HIGH TEMPS WILL GENERALLY BE NEAR TO SLIGHTLY ABOVE NORMAL FOR THE
MID TO LATE WEEK TIME FRAME... THEN NEAR NORMAL TO POSSIBLY SLIGHT
BELOW NORMAL FOR THE WEEKEND. LOW TEMPS ARE EXPECTED TO BE NEAR TO
SLIGHTLY ABOVE NORMAL DURING THE PERIOD.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AS OF 657 AM MONDAY...
DAMPENING MID-LEVEL OVER THE WESTERN CAROLINAS WILL MOVE NORTHEASTWARD
ACROSS THE AREA THIS MORNING AND OFF THE MID-ATLANTIC COAST BY THE
AFTERNOON. ASSOCIATED PLUME OF TROPICAL MOISTURE OVER THE AREA WILL
EVENTUALLY SHIFT OFFSHORE BY THE AFTERNOON. EXPECT WIDESPREAD RAIN
TO MOVE STEADILY WEST TO EAST WITH ASSOCIATED IFR TO MVFR
CEILINGS/VISIBILITIES.
AS THE SYSTEM LIFTS AWAY FROM THE AREA AND THE TROPICAL MOISTURE
PLUME SHIFTS OFFSHORE...CONDITIONS SHOULD IMPROVE TO VFR FROM WEST
TO EAST DURING THE EARLY TO MID AFTERNOON. DAYTIME HEATING COULD
ALLOW FOR ISOLATED TO SCATTERED SHOWERS DURING THE
AFTERNOON...ALTHOUGH CONFIDENCE IS TOO LOW TO INCLUDE AT THIS TIME.
EASTERN TERMINALS COULD SEE WIDESPREAD STRATUS/FOG MONDAY
NIGHT/TUESDAY MORNING WITH VFR CONDITIONS RETURNING ON TUESDAY.
OUTSIDE OF ISOLATED TO WIDELY SCATTERED DIURNAL CONVECTION...EXPECT
PREDOMINATELY VFR CONDITIONS TUESDAY NIGHT THROUGH FRIDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...KS
NEAR TERM...HARTFIELD/CBL
SHORT TERM...CBL
LONG TERM...77
AVIATION...CBL
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1000 AM CDT MON AUG 31 2015
.UPDATE...
ISSUED AT 956 AM CDT MON AUG 31 2015
AT 9 PM CDT...A COLD FRONT WAS PROCEEDING THROUGH THE EASTERN
PORTION OF THE STATE. SKIES WERE CLEARING ACROSS THE WEST. BREEZY
CONDITIONS WILL SOON DEVELOP WEST. TRIMMED THE POPS BACK TO FOLLOW
THE FRONTAL BOUNDARY EAST. THE CHANCES FOR PRECIP WILL END BY
NOON. TEMPERATURES LOOK GOOD.
UPDATE ISSUED AT 632 AM CDT MON AUG 31 2015
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS CONTINUE TO LIFT
NORTHEAST ACROSS NORTHERN AND EASTERN NORTH DAKOTA. CONVECTION HAS
EXITED THE SOUTHWEST QUARTER OF THE STATE. MAIN UPDATE WAS TO POPS
BASED ON LATEST RADAR AND THE TIME LAGGED HRRR OUTPUT THROUGH THIS
MORNING. OTHERWISE NO SIGNIFICANT UPDATES NEEDED.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 335 AM CDT MON AUG 31 2015
SHOWERS AND THUNDERSTORMS ENDING BY NOON. THEN BREEZY WEST WINDS
BRING A DRIER AND COOLER AIRMASS INTO THE STATE.
A SURFACE COLD FRONT EXTENDED FROM AROUND LAKE WINNIPEG
SOUTHWESTWARD TO THE TURTLE MOUNTAIN AND DEVILS LAKE AREA...TO NEAR
BISMARCK TO THE BLACK HILLS AREA IN WESTERN SOUTH DAKOTA. SCATTERED
SHOWERS AND THUNDERSTORMS CONTINUED TO DEVELOP ALONG AND WEST OF THE
SURFACE FRONT...MOVING NORTHEASTWARD ALONG THE UPPER LEVEL FLOW. AT
UPPER LEVELS...A SERIES OF UPPER LEVEL IMPULSES WERE MOVING
NORTHEASTWARD FROM WYOMING INTO THE CENTRAL AND WESTERN DAKOTAS. A
STRONG UPPER LEVEL SHORTWAVE WAS FARTHER WEST OVER CENTRAL
MONTANA/SOUTHERN SASKATCHEWAN...AND IS FORECAST TO CONTINUE LIFTING
NORTHEASTWARD ACROSS NORTHWESTERN NORTH DAKOTA AND INTO SOUTHERN
MANITOBA.
THE SURFACE COLD FRONT IS FORECAST TO MOVE EAST...REACHING THE RED
RIVER VALLEY AREA AROUND NOON. THE SHOWERS AND THUNDERSTORMS SHOULD
BE ENDING IN THE SOUTHWEST EARLY THIS MORNING...AND ENDING BY EARLY
AFTERNOON IN THE FAR NORTH AND JAMES RIVER VALLEY. THIS SHOULD OCCUR
AS THE LAST OF THE UPPER LEVEL IMPULSES AND STRONG SHORTWAVE MOVE
EAST OUT OF WESTERN AND CENTRAL NORTH DAKOTA.
A SECONDARY SURGE OF COOLER AND DRIER AIR WELL BEHIND THE FRONT
IS PROGGED TO PUSH INTO FAR WESTERN NORTH DAKOTA BEFORE DAYBREAK
THIS MORNING...WITH H850 WINDS OF 25 TO 35 KNOTS AT THE LEADING EDGE
OF THE AIRMASS. THIS IS DRY AIR MOVING ACROSS THE ROCKIES AND INTO
THE FRONT RANGE. CURRENT DEWPOINT TEMPERATURES IN THE WEST WERE IN
THE 50S WITH 60S IN THE EASTERN HALF OF THE STATE. THIS AFTERNOON
THE DEWPOINTS SHOULD BE AS LOW AS THE LOW TO MID 30S IN WESTERN
NORTH DAKOTA...AND IN THE 40S AND 50S EAST. HIGHS IN THE UPPER 70S
WEST WILL RESULT IN AFTERNOON MINIMUM RELATIVE HUMIDITY VALUES
AROUND 20 PERCENT. WEST WINDS OF 20 TO 25 MPH WITH GUSTS TO 30 MPH
CAN BE EXPECTED LATER THIS MORNING...BUT SHOULD DIMINISH SOMEWHAT
THIS AFTERNOON AFTER THE INITIAL PUSH OF DRY AIR. THUS THE STRONGEST
WINDS TODAY SHOULD NOT COINCIDE WITH THE LOWEST RELATIVE HUMIDITY
VALUES...AND RED FLAG CRITERIA ARE NOT EXPECTED TO BE MET.
LOOK FOR BREEZY WEST WINDS TO DEVELOP TODAY WITH DECREASING CLOUDS
FROM SOUTHWEST TO NORTHEAST. HIGHS SHOULD RANGE FROM THE UPPER 70S
NORTH AND WEST TO THE LOW TO MID 80S SOUTH CENTRAL.
DECREASING WINDS THIS EVENING WITH CLEAR SKIES. LOWS SHOULD BE
MAINLY IN THE 50S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 335 AM CDT MON AUG 31 2015
CONTINUED WARM TEMPERATURES AND SLIGHT/PERIODIC THUNDERSTORM CHANCES
WILL HIGHLIGHT THE EXTENDED FORECAST PERIOD THROUGH THE WORK WEEK.
MODEL DIFFERENCES APPEAR BY THE WEEKEND WITH A POSSIBLE PATTERN
CHANGE INTO THE EARLY PORTIONS OF NEXT WEEK.
ON TUESDAY...MAINTAINED A SLIGHT CHANCE OF MAINLY EVENING AND
OVERNIGHT THUNDERSTORMS FOR THE DEVILS LAKE BASIN AND JAMES RIVER
VALLEY WITH MODELS STILL SHOWING INCREASING INSTABILITY WITH DAYTIME
HEATING COUPLED WITH AN INCREASING LOW LEVEL JET ACROSS THE EASTERN
HALF OF THE STATE. CAPPING DURING THE DAY MAY HOLD OFF ON CONVECTION
UNTIL AFTER 00Z.
BEYOND TUESDAY...OUR SOUTHWEST UPPER FLOW WILL CONTINUE THROUGH THE
END OF THE WORK WEEK WITH TROUGHING ACROSS THE PACIFIC NORTHWEST AND
RIDGING OFF TO OUR EAST. A QUASI-STATIONARY SURFACE TROUGH COMBINED
WITH ANY EMBEDDED WAVES ALOFT WILL PROVIDE A FOCUS FOR MAINLY
ISOLATED DAILY SHOWER AND THUNDERSTORM ACTIVITY. BEST CHANCES APPEAR
TO BE TOWARDS THE END OF THE WORK WEEK AND INTO NEXT WEEKEND WHEN A
STRONG UPPER JET APPROACHES THE NORTHERN PLAINS. TEMPERATURES WILL
REMAIN NEAR TO SLIGHTLY ABOVE NORMAL THROUGH THE WORK WEEK.
DISAGREEMENT IN DETERMINISTIC MODELS CROPS UP BY THE WEEKEND
REGARDING THE STRONG UPPER LEVEL TROUGH TO OUR WEST. THE 00 UTC 31
AUG GFS IS NOW MUCH MORE PROGRESSIVE AND WEAKER WITH THIS FEATURE.
THUS COOLER CONDITIONS ENTER THE NORTHERN PLAINS SATURDAY AND SUNDAY
WITH A WARM-UP RETURNING BY THE BEGINNING OF NEXT WEEK. THE ECMWF
IS MUCH SLOWER AND STRONGER...KEEPING IT MILD THROUGH THE FIRST
HALF OF THE WEEKEND...THEN COOLING SUNDAY INTO EARLY NEXT WEEK AND
WITH MUCH COLDER TEMPERATURES OVER THE AREA EARLY NEXT WEEK. THE
GLOBAL GEM WAS ALSO SHOWING A SLOWER SOLUTION THAN THE GFS THROUGH
SUNDAY. THE GFSENSEMBLE SPREAD WAS MUCH GREATER LATE IN THE
WEEKEND COMPARED TO THE ECMWF ENSEMBLE...THUS MAYBE AN INDICATION
THAT THE SLOWER SOLUTION WILL PREVAIL. BUT FOR NOW WILL HOLD
STEADY WITH OUR CURRENT MODEL BLEND SOLUTION WHICH IS STILL
TRENDING COOLER FOR THE WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 632 AM CDT MON AUG 31 2015
SCATTERED THUNDERSTORMS ARE POSSIBLE AT KISN/KMOT/KJMS THIS MORNING.
THOUGH NOT OUT OF THE QUESTION...IT APPEARS THAT THE THUNDERSTORM
THREAT AT KDIK AND KBIS HAS PASSED. A COLD FRONT EXTENDED FROM NEAR
DEVILS LAKE TO NEAR STEELE TO LINTON...TO NEAR MOBRIDGE IN SOUTH
DAKOTA. COOLER AND DRIER AIR WAS PUSHING INTO THE WESTERN PART OF
NORTH DAKOTA. NORTHWEST WINDS HAD JUST BEGUN TO INCREASE AT CROSBY.
INCREASE OF NORTHWEST WINDS SHOULD SPREAD FROM NORTHWEST TO
SOUTHEAST AT TAF SITES...BEGINNING AT KISN SOON AFTER 12Z AND
REACHING KJMS BY AROUND 18Z. DECREASING WINDS AFT 00Z.
SMOKE MAY BECOME MORE WIDESPREAD AND THICKER THROUGH THE
DAY...BUT NOT CONFIDENT REGARDING AFFECTS AT THE SURFACE AT MOST TAF
SITES. MENTIONED VSBY REDUCTION AT KBIS WITH 4SM REPORTED AT 6 AM
CDT BECAUSE OF SMOKE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...JV
LONG TERM...TWH
AVIATION...JV
AREA FORECAST DISCUSSION
NWS BISMARCK ND
637 AM CDT MON AUG 31 2015
.UPDATE...
ISSUED AT 632 AM CDT MON AUG 31 2015
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS CONTINUE TO LIFT
NORTHEAST ACROSS NORTHERN AND EASTERN NORTH DAKOTA. CONVECTION HAS
EXITED THE SOUTHWEST QUARTER OF THE STATE. MAIN UPDATE WAS TO POPS
BASED ON LATEST RADAR AND THE TIME LAGGED HRRR OUTPUT THROUGH THIS
MORNING. OTHERWISE NO SIGNIFICANT UPDATES NEEDED.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 335 AM CDT MON AUG 31 2015
SHOWERS AND THUNDERSTORMS ENDING BY NOON. THEN BREEZY WEST WINDS
BRING A DRIER AND COOLER AIRMASS INTO THE STATE.
A SURFACE COLD FRONT EXTENDED FROM AROUND LAKE WINNIPEG
SOUTHWESTWARD TO THE TURTLE MOUNTAIN AND DEVILS LAKE AREA...TO NEAR
BISMARCK TO THE BLACK HILLS AREA IN WESTERN SOUTH DAKOTA. SCATTERED
SHOWERS AND THUNDERSTORMS CONTINUED TO DEVELOP ALONG AND WEST OF THE
SURFACE FRONT...MOVING NORTHEASTWARD ALONG THE UPPER LEVEL FLOW. AT
UPPER LEVELS...A SERIES OF UPPER LEVEL IMPULSES WERE MOVING
NORTHEASTWARD FROM WYOMING INTO THE CENTRAL AND WESTERN DAKOTAS. A
STRONG UPPER LEVEL SHORTWAVE WAS FARTHER WEST OVER CENTRAL
MONTANA/SOUTHERN SASKATCHEWAN...AND IS FORECAST TO CONTINUE LIFTING
NORTHEASTWARD ACROSS NORTHWESTERN NORTH DAKOTA AND INTO SOUTHERN
MANITOBA.
THE SURFACE COLD FRONT IS FORECAST TO MOVE EAST...REACHING THE RED
RIVER VALLEY AREA AROUND NOON. THE SHOWERS AND THUNDERSTORMS SHOULD
BE ENDING IN THE SOUTHWEST EARLY THIS MORNING...AND ENDING BY EARLY
AFTERNOON IN THE FAR NORTH AND JAMES RIVER VALLEY. THIS SHOULD OCCUR
AS THE LAST OF THE UPPER LEVEL IMPULSES AND STRONG SHORTWAVE MOVE
EAST OUT OF WESTERN AND CENTRAL NORTH DAKOTA.
A SECONDARY SURGE OF COOLER AND DRIER AIR WELL BEHIND THE FRONT
IS PROGGED TO PUSH INTO FAR WESTERN NORTH DAKOTA BEFORE DAYBREAK
THIS MORNING...WITH H850 WINDS OF 25 TO 35 KNOTS AT THE LEADING EDGE
OF THE AIRMASS. THIS IS DRY AIR MOVING ACROSS THE ROCKIES AND INTO
THE FRONT RANGE. CURRENT DEWPOINT TEMPERATURES IN THE WEST WERE IN
THE 50S WITH 60S IN THE EASTERN HALF OF THE STATE. THIS AFTERNOON
THE DEWPOINTS SHOULD BE AS LOW AS THE LOW TO MID 30S IN WESTERN
NORTH DAKOTA...AND IN THE 40S AND 50S EAST. HIGHS IN THE UPPER 70S
WEST WILL RESULT IN AFTERNOON MINIMUM RELATIVE HUMIDITY VALUES
AROUND 20 PERCENT. WEST WINDS OF 20 TO 25 MPH WITH GUSTS TO 30 MPH
CAN BE EXPECTED LATER THIS MORNING...BUT SHOULD DIMINISH SOMEWHAT
THIS AFTERNOON AFTER THE INITIAL PUSH OF DRY AIR. THUS THE STRONGEST
WINDS TODAY SHOULD NOT COINCIDE WITH THE LOWEST RELATIVE HUMIDITY
VALUES...AND RED FLAG CRITERIA ARE NOT EXPECTED TO BE MET.
LOOK FOR BREEZY WEST WINDS TO DEVELOP TODAY WITH DECREASING CLOUDS
FROM SOUTHWEST TO NORTHEAST. HIGHS SHOULD RANGE FROM THE UPPER 70S
NORTH AND WEST TO THE LOW TO MID 80S SOUTH CENTRAL.
DECREASING WINDS THIS EVENING WITH CLEAR SKIES. LOWS SHOULD BE
MAINLY IN THE 50S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 335 AM CDT MON AUG 31 2015
CONTINUED WARM TEMPERATURES AND SLIGHT/PERIODIC THUNDERSTORM CHANCES
WILL HIGHLIGHT THE EXTENDED FORECAST PERIOD THROUGH THE WORK WEEK.
MODEL DIFFERENCES APPEAR BY THE WEEKEND WITH A POSSIBLE PATTERN
CHANGE INTO THE EARLY PORTIONS OF NEXT WEEK.
ON TUESDAY...MAINTAINED A SLIGHT CHANCE OF MAINLY EVENING AND
OVERNIGHT THUNDERSTORMS FOR THE DEVILS LAKE BASIN AND JAMES RIVER
VALLEY WITH MODELS STILL SHOWING INCREASING INSTABILITY WITH DAYTIME
HEATING COUPLED WITH AN INCREASING LOW LEVEL JET ACROSS THE EASTERN
HALF OF THE STATE. CAPPING DURING THE DAY MAY HOLD OFF ON CONVECTION
UNTIL AFTER 00Z.
BEYOND TUESDAY...OUR SOUTHWEST UPPER FLOW WILL CONTINUE THROUGH THE
END OF THE WORK WEEK WITH TROUGHING ACROSS THE PACIFIC NORTHWEST AND
RIDGING OFF TO OUR EAST. A QUASI-STATIONARY SURFACE TROUGH COMBINED
WITH ANY EMBEDDED WAVES ALOFT WILL PROVIDE A FOCUS FOR MAINLY
ISOLATED DAILY SHOWER AND THUNDERSTORM ACTIVITY. BEST CHANCES APPEAR
TO BE TOWARDS THE END OF THE WORK WEEK AND INTO NEXT WEEKEND WHEN A
STRONG UPPER JET APPROACHES THE NORTHERN PLAINS. TEMPERATURES WILL
REMAIN NEAR TO SLIGHTLY ABOVE NORMAL THROUGH THE WORK WEEK.
DISAGREEMENT IN DETERMINISTIC MODELS CROPS UP BY THE WEEKEND
REGARDING THE STRONG UPPER LEVEL TROUGH TO OUR WEST. THE 00 UTC 31
AUG GFS IS NOW MUCH MORE PROGRESSIVE AND WEAKER WITH THIS FEATURE.
THUS COOLER CONDITIONS ENTER THE NORTHERN PLAINS SATURDAY AND SUNDAY
WITH A WARM-UP RETURNING BY THE BEGINNING OF NEXT WEEK. THE ECMWF
IS MUCH SLOWER AND STRONGER...KEEPING IT MILD THROUGH THE FIRST
HALF OF THE WEEKEND...THEN COOLING SUNDAY INTO EARLY NEXT WEEK AND
WITH MUCH COLDER TEMPERATURES OVER THE AREA EARLY NEXT WEEK. THE
GLOBAL GEM WAS ALSO SHOWING A SLOWER SOLUTION THAN THE GFS THROUGH
SUNDAY. THE GFSENSEMBLE SPREAD WAS MUCH GREATER LATE IN THE
WEEKEND COMPARED TO THE ECMWF ENSEMBLE...THUS MAYBE AN INDICATION
THAT THE SLOWER SOLUTION WILL PREVAIL. BUT FOR NOW WILL HOLD
STEADY WITH OUR CURRENT MODEL BLEND SOLUTION WHICH IS STILL
TRENDING COOLER FOR THE WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 632 AM CDT MON AUG 31 2015
SCATTERED THUNDERSTORMS ARE POSSIBLE AT KISN/KMOT/KJMS THIS MORNING.
THOUGH NOT OUT OF THE QUESTION...IT APPEARS THAT THE THUNDERSTORM
THREAT AT KDIK AND KBIS HAS PASSED. A COLD FRONT EXTENDED FROM NEAR
DEVILS LAKE TO NEAR STEELE TO LINTON...TO NEAR MOBRIDGE IN SOUTH
DAKOTA. COOLER AND DRIER AIR WAS PUSHING INTO THE WESTERN PART OF
NORTH DAKOTA. NORTHWEST WINDS HAD JUST BEGUN TO INCREASE AT CROSBY.
INCREASE OF NORTHWEST WINDS SHOULD SPREAD FROM NORTHWEST TO
SOUTHEAST AT TAF SITES...BEGINNING AT KISN SOON AFTER 12Z AND
REACHING KJMS BY AROUND 18Z. DECREASING WINDS AFT 00Z.
SMOKE MAY BECOME MORE WIDESPREAD AND THICKER THROUGH THE
DAY...BUT NOT CONFIDENT REGARDING AFFECTS AT THE SURFACE AT MOST TAF
SITES. MENTIONED VSBY REDUCTION AT KBIS WITH 4SM REPORTED AT 6 AM
CDT BECAUSE OF SMOKE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...JV
LONG TERM...TWH
AVIATION...JV
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1137 AM EDT MON AUG 31 2015
.SYNOPSIS...
A MODERATELY HIGH AMOUNT OF MOISTURE STREAMING EAST FROM THE OHIO
VALLEY WILL EXTEND ACROSS PENN THROUGH MUCH OF THIS WEEK. THE
CLOSE PROXIMITY OF A NEARLY EAST-WEST FRONTAL BOUNDARY ACROSS
PENNSYLVANIA WILL LEAD TO ISOLATED SHOWERS TODAY THROUGH
THURSDAY.
HIGH PRESSURE OFF THE EAST COAST WILL RIDGE NORTHWEST INTO
PENNSYLVANIA AND LEAD TO TEMPERATURES WELL ABOVE NORMAL THIS
ENTIRE WEEK. IT WILL FEEL MORE LIKE THE MIDDLE OF SUMMER THAN
SEPTEMBER.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
1130 AM UPDATE...
SHOWERS DEVELOPING QUICKLY OVER THE LAURELS. SOME 50+ DBZ RETURNS
IN EACH CELL...BUT SO FAR NO LTG. WILL ASUME THAT THIS IS
INEVITABLE AND KEEP THUNDER IN THE FCST. 40-50 POPS ALONG THE SRN
BORDER WILL DO WELL. AS WITH YESTERDAY...THE CELLS ARE MOVING
ALONG SLOWLY...BUT ONE OR TWO WHICH ANCHOR OR REDEVELOP OVER THE
SAME AREA COULD MAKE ISOLATED SPOTS OF HEAVY RAIN.
730 AM UPDATE...
RADAR RETURNS ACROSS THE SRN TIER ARE VERY LIGHT AND MAY STILL BE
ALOFT. PATCH HEADED FOR KTHV SHOULD TELL THE TALE. BUT IT IS ALSO
THE AREA OF HIGHEST RETURNS AS WELL. THUS...THE 30 POPS ACROSS THE
SRN TIER STILL LOOK STELLAR AND SFC CONVERGENCE AND HEATING UNDER
LESS CLOUDS IN THE NORTH WILL POP A FEW CELLS THIS AFTN.
PREV...
SFC HIGH PRESSURE LOCATED JUST OFF THE SE U.S. COAST WILL SLOWLY
BUILD NORTHWEST...AS AN UPPER RIDGE LOCATED OVER THE UPPER GLAKES
AND MISS VALLEY MOVES EAST TO THE OHIO RIVER VALLEY AND MID
ATLANTIC REGION BY 12Z TUES.
925-850 MB THETA-E RIDGE EXTENDS FROM THE OHIO VALLEY...ENE THROUGH
PENN EARLY TODAY...WITH A WEAK/STALLED-OUT SFC FRONT EXTENDING
FROM DETROIT...SW TO ST LOUIS. THE NORTHERN PART OF THIS FRONT
WILL MOVE STEADILY EAST/SOUTHEAST AND BECOME LOCATED ACROSS
CENTRAL PENN THIS EVENING...AND STAY THERE THROUGH MUCH OF
TUESDAY. A BIT OF DRYING WILL BE SEEN ACROSS THE REGION NEAR AND
TO THE NORTH OF INTERSTATE 80.
03Z SREF PROB OF CAPE EXCEEDING 1000 J/KG CLIMBS TO THE 60-80
PERCENT RANGE THIS AFTERNOON...HOWEVER THE PROB OF 2000 J/KG IS
VERY LOW AT 10 PERCENT OR LESS TODAY THROUGH THURSDAY...THUS THE
LOW DIURNAL POP/CVRG FOR CONVECTION. 07Z HRRR CONFIRMS THIS
THINKING AS IT PLACES GENERALLY ISOLATED- SCATTERED/POPCORN LIKE
COVERAGE BETWEEN 17Z-22Z TODAY.
PLENTY OF BKN-OVC ALTO CU /TOPPED BY SOME CIRRUS/ BLANKETED THE
SE HALF TO TWO-THIRDS OF PENN EARLY TODAY...WHILE MOSTLY CLEAR
SKIES AND THE COOLEST TEMPS IN THE L60S WERE FOUND INVOF KBFD.
ELSEWHERE...TEMPS RANGED FROM THE MID 60S TO MID 70S - A RATHER
MUGGY EARLY MORNING FOR THE FINAL DAY OF METEOROLOGICAL SUMMER.
ASIDE FROM A HIGHLY ISOLATED AND BRIEF LIGHT SHOWER OR TWO ON THE
RADAR SCOPE EARLY TODAY...CONDITIONS ACROSS MUCH OF CENTRAL AND
NORTHERN PENN WILL BE DRY WITH A VERY LIGHT AND VARIABLE WIND
THROUGH THE MID MORNING HOURS.
FARTHER SOUTH...WEAK UPPER LOW OVER THE WESTERN CAROLINAS WILL
LIFT NORTHWARD OVERNIGHT ON THE WESTERN PERIPHERY OF THE SPRAWLING
WESTERN ATLANTIC UPPER HIGH CIRCULATION. THIS WILL MAINTAIN THE
FOCUS FOR POOLING MOISTURE AND FORCING FOR SHOWER ACTIVITY THROUGH
THE PRE DAWN HOURS ACROSS MY FAR SOUTH. AGAIN...AREAS TO THE
NORTH SHOULD BE DRY AFTER 06Z AS DEFORMATION LESSENS AND FORCING
FOCUS SHIFTS TO AREAS ALONG AND SOUTH OF MY SOUTHERN TIER.
SOME FOG HAS FORMED...BUT VSBYS ARE HOLDING UP AOA 1 SM
MINS AROUND SUNRISE TODAY WILL RUN IN THE 60S IN PRACTICALLY ALL
LOCATIONS AS DEWPOINTS SHOULD NOT GO ANY LOWER THAN 60F. A FEW OF
THE NORMALLY COLD SPOTS NEAR...AND THE EAST OF KBFD WILL SEE A LOW
TEMP IN THE MID 50S.
HIGH TEMPS THIS AFTERNOON WILL VARY FROM THE U70S OVER THE HIGHEST
ELEVATIONS OF THE NORTH AND WEST...TO THE MID AND UPPER 80S ACROSS
OUR SE ZONES.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH 6 AM TUESDAY/...
TONIGHT SHOULD BE A NEAR REPEAT OF SUNDAY NIGHT/EARLY MONDAY WITH
VARIABLE AMTS OF MAINLY MID AND HIGH CLOUDS AND PERHAPS JUST A
COUPLE SMALL SHOWERS ROAMING THE STREETS.
CONSALL TEMP BLEND YIELDS LOWS AROUND 60F ACROSS THE NRN
MTNS...AND IN THE MID TO UPPER 60S ELSEWHERE.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
ANOMALOUS UPPER LEVEL RIDGE WILL DOMINATE THE OHIO VALLEY AND
EASTERN UNITED STATES MUCH OF THE UPCOMING WEEK...WITH LATEST
GUIDANCE REMAINING FIRM FOR AN EXTENDED RUN OF 850HPA TEMPS
PEAKING DAILY AROUND 16-18C. THIS WILL TRANSLATE TO WELL ABOVE-
NORMAL SFC TEMPS. THIS WARMTH AND INCREASING HUMIDITY SHOULD ALLOW
FOR AT LEAST A SLIGHT CHC FOR DIURNAL CONVECTION EACH DAY...BUT
WARM MID-LEVELS WILL KEEP THE PROBABILITY OF WIDESPREAD RAINFALL
QUITE LOW.
BEST CHANCES FOR PRECIP WILL BE DURING THE MID-LATE WEEK PERIOD
/WED-THU-FRI/ WITH A COUPLE SUBTLE FEATURES. FIRST...A WEAK UPPER
LEVEL WAVE /BEST PROGGED ON THE ECMWF/ SLIPS OVERHEAD ON WED AS
BERMUDA HIGH BRIEFLY RECEDES. AT SAME TIME A WEAK BACKDOOR COLD
FRONT SLIPS SOUTHWARD OFF THE EAST COAST. THIS COULD HELP POOL
SOME LOW LEVEL MOISTURE OVER THE MID ATLANTIC AND OHIO VALLEY AS
MID LEVELS COOL JUST A BIT...BRINGING POTENTIAL FOR SCT TSTMS.
RIDGE BUILDS BACK IN FOR FRI...BUT ANOTHER SURFACE BACKDOOR FRONT
TRIES TO SLIP ACROSS THE STATE AS SURFACE HIGH EXPANDS IN FROM THE
NORTH. THIS BOUNDARY SHOULD BRING SCT CONVECTION FOR FRI.
EXTENDED MODELS HINT AT POTENTIAL FOR DAILY CONVECTION CONTINUING
INTO THE WEEKEND ALONG SOUTHER BORDER...BUT OVERALL CONDITIONS
WILL BE MAINLY RAIN-FREE.
TEMPS PEAK MIDWEEK WITH READINGS APPROACHING 90F IN THE SE...AND
EVEN GETTING INTO THE 80S ELSE HERE...EASILY WELL ABOVE NORMAL
FOR THE FIRST WEEK OF SEPT. LOWS WILL ALSO REMAIN QUITE MILD
MID/LATE WEEK AS HIGH HUMIDITY AIR HANGS AROUND. SLIGHTLY COOLER
BUT STILL ABOVE AVERAGE TEMPS WILL CONTINUE THROUGH THE WEEKEND.
&&
.AVIATION /16Z MONDAY THROUGH FRIDAY/...
WIDESPREAD VFR CONDS AND LIGHT WIND APPEAR VERY LIKELY WITH ISOLD
TO SCT SHRA/TSRA OVER THE SRN TIER AND NRN MTNS. THE MAY BE A
SHRA OR TWO IN THE CENTRAL MTNS...BUT LESS OF A CHANCE OF ANY
VSBY/CIG REDUCTIONS THERE. HIGH PRESSURE WILL REMAIN OFF THE MID
ATLANTIC COAST.
OUTLOOK...
TUE-FRI...PATCHY AM FOG POSS...MAINLY KBFD. ISOLD PM TSRA IMPACTS
POSSIBLE...MAINLY W.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/RXR
AVIATION...DANGELO/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
754 AM EDT MON AUG 31 2015
.SYNOPSIS...
A MODERATELY HIGH AMOUNT OF MOISTURE STREAMING EAST FROM THE OHIO
VALLEY WILL EXTEND ACROSS PENN THROUGH MUCH OF THIS WEEK. THE
CLOSE PROXIMITY OF A NEARLY EAST-WEST FRONTAL BOUNDARY ACROSS
PENNSYLVANIA WILL LEAD TO ISOLATED MAINLY AFTERNOON AND EARLY
EVENING SHRA/TSRA TODAY THROUGH THURSDAY.
HIGH PRESSURE OFF THE EAST COAST WILL RIDGE NORTHWEST INTO
PENNSYLVANIA AND LEAD TO TEMPERATURES WELL ABOVE NORMAL THIS
ENTIRE WEEK. IT WILL FEEL MORE LIKE THE MIDDLE OF SUMMER THAN
SEPTEMBER.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
730 AM UPDATE...
RADAR RETURNS ACROSS THE SRN TIER ARE VERY LIGHT AND MAY STILL BE
ALOFT. PATCH HEADED FOR KTHV SHOULD TELL THE TALE. BUT IT IS ALSO
THE AREA OF HIGHEST RETURNS AS WELL. THUS...THE 30 POPS ACROSS THE
SRN TIER STILL LOOK STELLAR AND SFC CONVERGENCE AND HEATING UNDER
LESS CLOUDS IN THE NORTH WILL POP A FEW CELLS THIS AFTN.
PREV...
SFC HIGH PRESSURE LOCATED JUST OFF THE SE U.S. COAST WILL SLOWLY
BUILD NORTHWEST...AS AN UPPER RIDGE LOCATED OVER THE UPPER GLAKES
AND MISS VALLEY MOVES EAST TO THE OHIO RIVER VALLEY AND MID
ATLANTIC REGION BY 12Z TUES.
925-850 MB THETA-E RIDGE EXTENDS FROM THE OHIO VALLEY...ENE THROUGH
PENN EARLY TODAY...WITH A WEAK/STALLED-OUT SFC FRONT EXTENDING
FROM DETROIT...SW TO ST LOUIS. THE NORTHERN PART OF THIS FRONT
WILL MOVE STEADILY EAST/SOUTHEAST AND BECOME LOCATED ACROSS
CENTRAL PENN THIS EVENING...AND STAY THERE THROUGH MUCH OF
TUESDAY. A BIT OF DRYING WILL BE SEEN ACROSS THE REGION NEAR AND
TO THE NORTH OF INTERSTATE 80.
03Z SREF PROB OF CAPE EXCEEDING 1000 J/KG CLIMBS TO THE 60-80
PERCENT RANGE THIS AFTERNOON...HOWEVER THE PROB OF 2000 J/KG IS
VERY LOW AT 10 PERCENT OR LESS TODAY THROUGH THURSDAY...THUS THE
LOW DIURNAL POP/CVRG FOR CONVECTION. 07Z HRRR CONFIRMS THIS
THINKING AS IT PLACES GENERALLY ISOLATED- SCATTERED/POPCORN LIKE
COVERAGE BETWEEN 17Z-22Z TODAY.
PLENTY OF BKN-OVC ALTO CU /TOPPED BY SOME CIRRUS/ BLANKETED THE
SE HALF TO TWO-THIRDS OF PENN EARLY TODAY...WHILE MOSTLY CLEAR
SKIES AND THE COOLEST TEMPS IN THE L60S WERE FOUND INVOF KBFD.
ELSEWHERE...TEMPS RANGED FROM THE MID 60S TO MID 70S - A RATHER
MUGGY EARLY MORNING FOR THE FINAL DAY OF METEOROLOGICAL SUMMER.
ASIDE FROM A HIGHLY ISOLATED AND BRIEF LIGHT SHOWER OR TWO ON THE
RADAR SCOPE EARLY TODAY...CONDITIONS ACROSS MUCH OF CENTRAL AND
NORTHERN PENN WILL BE DRY WITH A VERY LIGHT AND VARIABLE WIND
THROUGH THE MID MORNING HOURS.
FARTHER SOUTH...WEAK UPPER LOW OVER THE WESTERN CAROLINAS WILL
LIFT NORTHWARD OVERNIGHT ON THE WESTERN PERIPHERY OF THE SPRAWLING
WESTERN ATLANTIC UPPER HIGH CIRCULATION. THIS WILL MAINTAIN THE
FOCUS FOR POOLING MOISTURE AND FORCING FOR SHOWER ACTIVITY THROUGH
THE PRE DAWN HOURS ACROSS MY FAR SOUTH. AGAIN...AREAS TO THE
NORTH SHOULD BE DRY AFTER 06Z AS DEFORMATION LESSENS AND FORCING
FOCUS SHIFTS TO AREAS ALONG AND SOUTH OF MY SOUTHERN TIER.
SOME FOG HAS FORMED...BUT VSBYS ARE HOLDING UP AOA 1 SM
MINS AROUND SUNRISE TODAY WILL RUN IN THE 60S IN PRACTICALLY ALL
LOCATIONS AS DEWPOINTS SHOULD NOT GO ANY LOWER THAN 60F. A FEW OF
THE NORMALLY COLD SPOTS NEAR...AND THE EAST OF KBFD WILL SEE A LOW
TEMP IN THE MID 50S.
HIGH TEMPS THIS AFTERNOON WILL VARY FROM THE U70S OVER THE HIGHEST
ELEVATIONS OF THE NORTH AND WEST...TO THE MID AND UPPER 80S ACROSS
OUR SE ZONES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
TONIGHT SHOULD BE A NEAR REPEAT OF SUNDAY NIGHT/EARLY MONDAY WITH
VARIABLE AMTS OF MAINLY MID AND HIGH CLOUDS AND PERHAPS JUST A
COUPLE SMALL SHOWERS ROAMING THE STREETS.
CONSALL TEMP BLEND YIELDS LOWS AROUND 60F ACROSS THE NRN
MTNS...AND IN THE MID TO UPPER 60S ELSEWHERE.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
ANOMALOUS UPPER LEVEL RIDGE WILL DOMINATE THE OHIO VALLEY AND
EASTERN UNITED STATES MUCH OF THE UPCOMING WEEK...WITH LATEST
GUIDANCE REMAINING FIRM FOR AN EXTENDED RUN OF 850HPA TEMPS
PEAKING DAILY AROUND 16-18C. THIS WILL TRANSLATE TO WELL ABOVE-
NORMAL SFC TEMPS. THIS WARMTH AND INCREASING HUMIDITY SHOULD ALLOW
FOR AT LEAST A SLIGHT CHC FOR DIURNAL CONVECTION EACH DAY...BUT
WARM MID-LEVELS WILL KEEP THE PROBABILITY OF WIDESPREAD RAINFALL
QUITE LOW.
BEST CHANCES FOR PRECIP WILL BE DURING THE MID-LATE WEEK PERIOD
/WED-THU-FRI/ WITH A COUPLE SUBTLE FEATURES. FIRST...A WEAK UPPER
LEVEL WAVE /BEST PROGGED ON THE ECMWF/ SLIPS OVERHEAD ON WED AS
BERMUDA HIGH BRIEFLY RECEDES. AT SAME TIME A WEAK BACKDOOR COLD
FRONT SLIPS SOUTHWARD OFF THE EAST COAST. THIS COULD HELP POOL
SOME LOW LEVEL MOISTURE OVER THE MID ATLANTIC AND OHIO VALLEY AS
MID LEVELS COOL JUST A BIT...BRINGING POTENTIAL FOR SCT TSTMS.
RIDGE BUILDS BACK IN FOR FRI...BUT ANOTHER SURFACE BACKDOOR FRONT
TRIES TO SLIP ACROSS THE STATE AS SURFACE HIGH EXPANDS IN FROM THE
NORTH. THIS BOUNDARY SHOULD BRING SCT CONVECTION FOR FRI.
EXTENDED MODELS HINT AT POTENTIAL FOR DAILY CONVECTION CONTINUING
INTO THE WEEKEND ALONG SOUTHER BORDER...BUT OVERALL CONDITIONS
WILL BE MAINLY RAIN-FREE.
TEMPS PEAK MIDWEEK WITH READINGS APPROACHING 90F IN THE SE...AND
EVEN GETTING INTO THE 80S ELSE HERE...EASILY WELL ABOVE NORMAL
FOR THE FIRST WEEK OF SEPT. LOWS WILL ALSO REMAIN QUITE MILD
MID/LATE WEEK AS HIGH HUMIDITY AIR HANGS AROUND. SLIGHTLY COOLER
BUT STILL ABOVE AVERAGE TEMPS WILL CONTINUE THROUGH THE WEEKEND.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
EARLY MORNING FOG HAS REMAINED ISOLATED AT IPT AND BFD...WITH IFR
AND MVFR RESPECTIVELY. ANY AM VALLEY FOG WILL BURN OFF BY LATE
AM. OTHERWISE...WIDESPREAD VFR CONDS AND LIGHT WIND APPEAR VERY
LIKELY MONDAY WITH ONLY ISOLD LATE DAY SHRA/TSRA POSSIBLE...AS
HIGH PRESSURE BUILDS OFF THE MID ATLANTIC COAST. SHOWERS WILL BE
MOST LIKELY THROUGH THE SOUTHERN TAF SITES WITH LNS AND MDT MOST
LIKELY...MAINLY BETWEEN NOW AND THROUGH THE EARLY AFTERNOON HOURS.
OUTLOOK...
TUE-FRI...PATCHY AM FOG POSS...MAINLY KBFD. ISOLD PM TSRA IMPACTS
POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/RXR
AVIATION...FITZGERALD/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
704 AM EDT MON AUG 31 2015
.SYNOPSIS...
A MODERATELY HIGH AMOUNT OF MOISTURE STREAMING EAST FROM THE OHIO
VALLEY WILL EXTEND ACROSS PENN THROUGH MUCH OF THIS WEEK. THE
CLOSE PROXIMITY OF A NEARLY EAST-WEST FRONTAL BOUNDARY ACROSS
PENNSYLVANIA WILL LEAD TO ISOLATED MAINLY AFTERNOON AND EARLY
EVENING SHRA/TSRA TODAY THROUGH THURSDAY.
HIGH PRESSURE OFF THE EAST COAST WILL RIDGE NORTHWEST INTO
PENNSYLVANIA AND LEAD TO TEMPERATURES WELL ABOVE NORMAL THIS
ENTIRE WEEK. IT WILL FEEL MORE LIKE THE MIDDLE OF SUMMER THAN
SEPTEMBER.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SFC HIGH PRESSURE LOCATED JUST OFF THE SE U.S. COAST WILL SLOWLY
BUILD NORTHWEST...AS AN UPPER RIDGE LOCATED OVER THE UPPER GLAKES
AND MISS VALLEY MOVES EAST TO THE OHIO RIVER VALLEY AND MID
ATLANTIC REGION BY 12Z TUES.
925-850 MB THETA-E RIDGE EXTENDS FROM THE OHIO VALLEY...ENE THROUGH
PENN EARLY TODAY...WITH A WEAK/STALLED-OUT SFC FRONT EXTENDING
FROM DETROIT...SW TO ST LOUIS. THE NORTHERN PART OF THIS FRONT
WILL MOVE STEADILY EAST/SOUTHEAST AND BECOME LOCATED ACROSS
CENTRAL PENN THIS EVENING...AND STAY THERE THROUGH MUCH OF
TUESDAY. A BIT OF DRYING WILL BE SEEN ACROSS THE REGION NEAR AND
TO THE NORTH OF INTERSTATE 80.
03Z SREF PROB OF CAPE EXCEEDING 1000 J/KG CLIMBS TO THE 60-80
PERCENT RANGE THIS AFTERNOON...HOWEVER THE PROB OF 2000 J/KG IS
VERY LOW AT 10 PERCENT OR LESS TODAY THROUGH THURSDAY...THUS THE
LOW DIURNAL POP/CVRG FOR CONVECTION. 07Z HRRR CONFIRMS THIS
THINKING AS IT PLACES GENERALLY ISOLATED- SCATTERED/POPCORN LIKE
COVERAGE BETWEEN 17Z-22Z TODAY.
PLENTY OF BKN-OVC ALTO CU /TOPPED BY SOME CIRRUS/ BLANKETED THE
SE HALF TO TWO-THIRDS OF PENN EARLY TODAY...WHILE MOSTLY CLEAR
SKIES AND THE COOLEST TEMPS IN THE L60S WERE FOUND INVOF KBFD.
ELSEWHERE...TEMPS RANGED FROM THE MID 60S TO MID 70S - A RATHER
MUGGY EARLY MORNING FOR THE FINAL DAY OF METEOROLOGICAL SUMMER.
ASIDE FROM A HIGHLY ISOLATED AND BRIEF LIGHT SHOWER OR TWO ON THE
RADAR SCOPE EARLY TODAY...CONDITIONS ACROSS MUCH OF CENTRAL AND
NORTHERN PENN WILL BE DRY WITH A VERY LIGHT AND VARIABLE WIND
THROUGH THE MID MORNING HOURS.
FARTHER SOUTH...WEAK UPPER LOW OVER THE WESTERN CAROLINAS WILL
LIFT NORTHWARD OVERNIGHT ON THE WESTERN PERIPHERY OF THE SPRAWLING
WESTERN ATLANTIC UPPER HIGH CIRCULATION. THIS WILL MAINTAIN THE
FOCUS FOR POOLING MOISTURE AND FORCING FOR SHOWER ACTIVITY THROUGH
THE PRE DAWN HOURS ACROSS MY FAR SOUTH. AGAIN...AREAS TO THE
NORTH SHOULD BE DRY AFTER 06Z AS DEFORMATION LESSENS AND FORCING
FOCUS SHIFTS TO AREAS ALONG AND SOUTH OF MY SOUTHERN TIER.
SOME FOG HAS FORMED...BUT VSBYS ARE HOLDING UP AOA 1 SM
MINS AROUND SUNRISE TODAY WILL RUN IN THE 60S IN PRACTICALLY ALL
LOCATIONS AS DEWPOINTS SHOULD NOT GO ANY LOWER THAN 60F. A FEW OF
THE NORMALLY COLD SPOTS NEAR...AND THE EAST OF KBFD WILL SEE A LOW
TEMP IN THE MID 50S.
HIGH TEMPS THIS AFTERNOON WILL VARY FROM THE U70S OVER THE HIGHEST
ELEVATIONS OF THE NORTH AND WEST...TO THE MID AND UPPER 80S ACROSS
OUR SE ZONES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
TONIGHT SHOULD BE A NEAR REPEAT OF SUNDAY NIGHT/EARLY MONDAY WITH
VARIABLE AMTS OF MAINLY MID AND HIGH CLOUDS AND PERHAPS JUST A
COUPLE SMALL SHOWERS ROAMING THE STREETS.
CONSALL TEMP BLEND YIELDS LOWS AROUND 60F ACROSS THE NRN
MTNS...AND IN THE MID TO UPPER 60S ELSEWHERE.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
ANOMALOUS UPPER LEVEL RIDGE WILL DOMINATE THE OHIO VALLEY AND
EASTERN UNITED STATES MUCH OF THE UPCOMING WEEK...WITH LATEST
GUIDANCE REMAINING FIRM FOR AN EXTENDED RUN OF 850HPA TEMPS
PEAKING DAILY AROUND 16-18C. THIS WILL TRANSLATE TO WELL ABOVE-
NORMAL SFC TEMPS. THIS WARMTH AND INCREASING HUMIDITY SHOULD ALLOW
FOR AT LEAST A SLIGHT CHC FOR DIURNAL CONVECTION EACH DAY...BUT
WARM MID-LEVELS WILL KEEP THE PROBABILITY OF WIDESPREAD RAINFALL
QUITE LOW.
BEST CHANCES FOR PRECIP WILL BE DURING THE MID-LATE WEEK PERIOD
/WED-THU-FRI/ WITH A COUPLE SUBTLE FEATURES. FIRST...A WEAK UPPER
LEVEL WAVE /BEST PROGGED ON THE ECMWF/ SLIPS OVERHEAD ON WED AS
BERMUDA HIGH BRIEFLY RECEDES. AT SAME TIME A WEAK BACKDOOR COLD
FRONT SLIPS SOUTHWARD OFF THE EAST COAST. THIS COULD HELP POOL
SOME LOW LEVEL MOISTURE OVER THE MID ATLANTIC AND OHIO VALLEY AS
MID LEVELS COOL JUST A BIT...BRINGING POTENTIAL FOR SCT TSTMS.
RIDGE BUILDS BACK IN FOR FRI...BUT ANOTHER SURFACE BACKDOOR FRONT
TRIES TO SLIP ACROSS THE STATE AS SURFACE HIGH EXPANDS IN FROM THE
NORTH. THIS BOUNDARY SHOULD BRING SCT CONVECTION FOR FRI.
EXTENDED MODELS HINT AT POTENTIAL FOR DAILY CONVECTION CONTINUING
INTO THE WEEKEND ALONG SOUTHER BORDER...BUT OVERALL CONDITIONS
WILL BE MAINLY RAIN-FREE.
TEMPS PEAK MIDWEEK WITH READINGS APPROACHING 90F IN THE SE...AND
EVEN GETTING INTO THE 80S ELSE HERE...EASILY WELL ABOVE NORMAL
FOR THE FIRST WEEK OF SEPT. LOWS WILL ALSO REMAIN QUITE MILD
MID/LATE WEEK AS HIGH HUMIDITY AIR HANGS AROUND. SLIGHTLY COOLER
BUT STILL ABOVE AVERAGE TEMPS WILL CONTINUE THROUGH THE WEEKEND.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
EARLY MORNING FOG HAS REMAINED ISOLATED AT IPT AND BFD...WITH IFR
AND MVFR RESPECTIVELY. ANY AM VALLEY FOG WILL BURN OFF BY LATE
AM. OTHERWISE...WIDESPREAD VFR CONDS AND LIGHT WIND APPEAR VERY
LIKELY MONDAY WITH ONLY ISOLD LATE DAY SHRA/TSRA POSSIBLE...AS
HIGH PRESSURE BUILDS OFF THE MID ATLANTIC COAST. SHOWERS WILL BE
MOST LIKELY THROUGH THE SOUTHERN TAF SITES WITH LNS AND MDT MOST
LIKELY...MAINLY BETWEEN NOW AND THROUGH THE EARLY AFTERNOON HOURS.
OUTLOOK...
TUE-FRI...PATCHY AM FOG POSS...MAINLY KBFD. ISOLD PM TSRA IMPACTS
POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/RXR
AVIATION...FITZGERALD/CERU
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
859 AM MDT MON AUG 31 2015
.UPDATE...
ISSUED AT 852 AM MDT MON AUG 31 2015
UPPER WAVE CONTINUES TO PUSH THROUGH THE NORTHERN PLAINS. RADAR
STILL INDICATES SHOWER ACTIVITY BEHIND THE COLD FRONT ACROSS
SOUTHWEST INTO CENTRAL SD. ADDED SOME ISOLATED SHOWERS THROUGH
THE DAY FOR ANY RAIN THAT MIGHT BE REACHING THE GROUND...ALTHOUGH
OBS STILL SHOW PRETTY DRY AIR SO IT MAY REMAIN VIRGA. INCREASED
CLOUD COVER TO REFLECT CURRENT TRENDS...BUT REST OF FORECAST LOOKS
ON TRACK FOR NOW.
&&
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
ISSUED AT 327 AM MDT MON AUG 31 2015
WATER VAPOR IMAGERY SHOWS STRONG UPPER WAVE CROSSING CNTRL TO ERN MT
INTO NRN WY. SURFACE ANALYSIS SHOWS LOW PRES ACROSS THE WRN/CNTRL
DAKOTAS AHEAD OF THE UPPER WAVE...WITH A COLD FRONT QUICKLY PUSHING
THRU ERN MT/CNTRL WY TOWARD THE CWA. TEMPS ACROSS THE CWA ARE IN THE
60S/70S...EVEN 80S ACROSS THE DOWNSLOPING N/NE BLKHLS. BEHIND THE
FRONT...OBS SHOWING TEMPS DROPPING INTO THE 50S WITH WINDS OF 15 TO
30 GUSTING TO 30 TO 40 MPH. RADAR SHOWS SHOWER ACTIVITY CROSSING WRN
SD...HOWEVER NEARLY ALL THE PRECIP IS VIRGA WITH LITTLE TO NO RAIN
REACHING THE GROUND. THE COLD FRONT WILL PUSH THROUGH NE WY TO WRN
SD IN THE NEXT 4/5 HOURS OR SO...AND CLEAR SCNTRL SD BY MID TO LATE
MORNING. HRRR SUGGESTS WINDS WILL GENERALLY BE 15 TO 25 MPH WITH
GUSTS TO 30 TO 40 MPH...BUT IS ALSO SHOWING STRONGER WINDS ACROSS
THE WRN SD PLAINS NORTH AND EAST OF THE BLKHLS. WIND ADVISORY
CRITERIA WINDS ARE EXPECTED...HOWEVER JUST FOR COUPLE HOURS OR SO
IMMEDIATELY AFTER THE FROPA. COULD SEE LINGERING SHRA ACTIVITY EARLY
THIS MORNING AS MODELS ARE HAVING A HARD TIME DECIDING HOW MUCH
PRECIP WILL REACH THE GROUND. WILL LEAN TOWARD A DRY FORECAST FOR
NOW CONSIDERING THE LATEST RADAR IMAGERY...BUT WILL REASSESS CLOSER
TO 12Z. OTHERWISE A DRY DAY IS EXPECTED WITH MUCH COOLER
TEMPERATURES AND CLEARING SKIES. HIGHS WILL REACH THE UPPER 70S TO
UPPER 80S. TEMPS TONIGHT WILL DROP INTO THE 50S TO LOWER 60S. RETURN
FLOW WILL SET UP BY MON NIGHT/TUE MRNG WITH WARMER TEMPS
EXPECTED. HIGHS WILL RETURN TO THE MID 80S TO MID 90S. DRY WEATHER
WILL CONTINUE TUE/TUE NIGHT WITH BROAD SWRLY FLOW ALOFT
PERSISTING.
.LONG TERM...WEDNESDAY THROUGH SUNDAY
ISSUED AT 327 AM MDT MON AUG 31 2015
THE UPPER TROUGH WILL REMAIN OVER THE NORTH AMERICAN PACIFIC
COAST THROUGH MOST OF THE WEEK...EVENTUALLY MOVING INLAND BY THE
WEEKEND AS ANOTHER IMPULSE DROPS INTO THE UPPER TROUGH FROM THE
NORTHWEST. THIS PATTERN WILL LEAD TO CONTINUED VERY WARM
TEMPERATURES OVER THE NORTHERN PLAINS BOTH WEDNESDAY AND THURSDAY.
FRIDAY AND SATURDAY WILL BE SLIGHTLY COOLER...WITH MUCH COOLER
TEMPS ON SUNDAY AND MONDAY BEHIND A RELATIVELY STRONG COLD FRONT
WHICH WILL PASS THROUGH THE AREA EARLY SUNDAY. DRY WEATHER IS
EXPECTED ON WEDNESDAY AND THURSDAY WITH A CHANCE OF THUNDERSTORMS
EACH DAY FROM FRIDAY THROUGH THE WEEKEND AS A SERIES OF UPPER
IMPULSES CROSS THE REGION AND COOLER AIR FLOWS IN AT THE SFC.
&&
.AVIATION...FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING
ISSUED AT 327 AM MDT MON AUG 31 2015
BREEZY NORTHWEST WINDS WILL FOLLOW A COLD FRONT THIS MORNING. VFR
CONDITIONS ARE EXPECTED TODAY AND TONIGHT.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
UPDATE...POJORLIE
SHORT TERM...13
LONG TERM...10
AVIATION...10
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1052 AM CDT MON AUG 31 2015
.UPDATE...
EARLIER FOG THIS MORNING HAS DISSIPATED WITH TEMPERATURES NOW INTO
THE UPPER 70S AND LOWER 80S. LATEST MODELS INCLUDING THE HRRR SHOW
LITTLE IN THE WAY OF CONVECTION TODAY...WITH BEST CHANCES OVER THE
SOUTHEAST THIRD OF THE CWA. ALTHOUGH CANNOT RULE OUT AN ISOLATED
STORM OR TWO ANYWHERE...WILL TRIM POPS BACK TO SOUTHERN AND
EASTERN ZONES FOR THIS AFTERNOON. REST OF FORECAST INCLUDING HIGH
TEMPS LOOKS GOOD.
SHAMBURGER
&&
.PREV DISCUSSION... /ISSUED 615 AM CDT MON AUG 31 2015/
AVIATION UPDATE...FOR 12Z TAF`S.
BNA/CKV/CSV...MORNING RADIATION FOG AT CKV & CSV SHOULD DISSIPATE
BY 14Z. HIGH PRESSURE CONTINUES TO BUILD INTO THE MID STATE FROM
THE NORTHEAST, WITH DRIER AIR NOW IN PLACE AND GREATLY REDUCED
POP`S. THERE MAY BE A STRAY ECHO OR TWO DURING THE AFTERNOON, BUT
WON`T MENTION PRECIP IN THE TAF`S. EXPECT FULL RADIATIONAL COOLING
AGAIN OVERNIGHT, SO FOG WILL MORE THAN LIKELY BECOME AN ISSUE.
PREV DISCUSSION... /ISSUED 300 AM CDT MON AUG 31 2015/
DISCUSSION...
AFTER A FEW SHOWERS AND THUNDERSTORMS YESTERDAY AFTERNOON THINGS
HAVE QUIETED DOWN CONSIDERABLY ACROSS MIDDLE TN. PARTLY TO MOSTLY
CLOUDY SKIES ARE BEING SEEN ACROSS THE AREA AND A FEW FOLKS ARE
EXPERIENCING PATCHY DENSE FOG...ESPECIALLY THOSE WHO SAW RAIN
YESTERDAY. THIS FOG WILL PERSIST UNTIL A COUPLE HOURS AFTER SUNRISE
THIS MORNING SO BE CAUTIOUS WHEN YOU HEAD OUT FOR THE MONDAY MORNING
COMMUTE AS SOME VISIBILITIES ARE BELOW 1 MILE.
BEYOND THIS MORNING`S FOG WE ARE IN FOR A FAIRLY STAGNANT PATTERN
OVER THE NEXT SEVERAL DAYS. WEAK RIDGING ALOFT WILL SETTLE IN AND
WITHOUT MUCH IN THE WAY OF RETURN FLOW...NOR A PUSH OF DRY AIR FROM
THE NORTH...DEW POINTS WILL REMAIN THE SAME THROUGHOUT THE WEEK AND
TEMPERATURES WILL WARM A DEGREE OR TWO EACH AFTERNOON. RAIN CHANCES
WILL BE LOW EACH AFTERNOON...BUT NOT ZERO...AS THERE WILL BE JUST
ENOUGH LOW LEVEL MOISTURE TO FEED A COUPLE OF STORMS EACH DAY.
COVERAGE WILL ALMOST BE NEGLIGIBLE.
OUR NEXT SHOT AT ANY SIGNIFICANT RAIN MIGHT BE OVER THE LABOR DAY
WEEKEND. WHILE THERE WON`T BE ANY FRONTAL PASSAGE...THE RIDGE ALOFT
FROM DURING THE WEEK MAY BEGIN TO BREAK DOWN AND GIVE US SOME
GENERAL TROUGHINESS OVER THE SOUTHEAST. THIS WON`T INCREASE POPS A
GREAT DEAL...BUT IT SHOULD OPEN THE DOOR FOR SLIGHTLY BETTER
COVERAGE SATURDAY AND SUNDAY AFTERNOONS. WHILE POPS MIGHT INCREASE A
LITTLE FOR THE UPCOMING HOLIDAY WEEKEND...IT DEFINITELY WON`T BE A
WASHOUT.
EXTENDED RANGE GUIDANCE IS ACTUALLY IN DECENT AGREEMENT ABOUT A
DIFFUSE FRONT TRYING TO PUSH INTO THE REGION AFTER LABOR DAY...SO
IT MAY BE AWHILE BEFORE ANY WIDESPREAD RAINS RETURNS TO THE
FORECAST.
UNGER
AVIATION...
06Z TAF DISCUSSION.
EARLIER SHOWERS HAVE DISSIPATED AND MUCH OF THE CLOUD COVER
OVERHEAD IS THINNING OUT. ONLY EXCEPTION IS CLOSER TO THE PLATEAU
AND THUS CSV WHERE A WEAK UPPER LOW IS LOCATED. CLOUD COVER AND
ISOLATED SHRA FROM THAT COULD STILL AFFECT CSV THROUGH ROUGHLY
12Z AS THE UPPER LOW PUSHES NORTHWARD INTO KY.
OTHERWISE...PARTIAL CLEARING AND AMPLE LOW LEVEL MOISTURE SHOULD
LEAD TO LIGHT FOG ACROSS MIDDLE TN. LOWEST VSBYS...AT TIMES BELOW
1 SM...SHOULD BE LOCATED AT CKV AND CSV FROM 07-13Z WHERE RAIN
FELL EARLIER TODAY. ONCE THE FOG BURNS OFF MID-MORNING
MONDAY...VFR CONDITIONS ARE EXPECTED THRU 06Z TUESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 88 68 91 70 / 10 10 20 10
CLARKSVILLE 87 66 90 68 / 10 10 20 0
CROSSVILLE 81 65 84 67 / 20 10 20 10
COLUMBIA 86 66 90 68 / 10 10 20 0
LAWRENCEBURG 85 67 89 68 / 20 10 20 10
WAVERLY 87 67 90 69 / 10 10 20 0
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
55
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
635 AM CDT MON AUG 31 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 340 AM CDT MON AUG 31 2015
EARLY THIS MORNING...LOW STRATUS HAS QUICKLY DEVELOPED ACROSS
NORTH-CENTRAL IA AND ALONG THE MN/IA BORDER AS WELL AS ACROSS
NORTHERN WI. 31.07Z RAP SHOWS THIS STRATUS FILLING-IN ACROSS MUCH
OF THE FORECAST AREA BY SUNRISE. THESE CLOUDS...COMBINED WITH
BRISK WEST-SOUTHWEST WIND JUST OFF THE SURFACE SHOULD PRECLUDE
WIDESPREAD DENSE FOG...BUT CAN STILL EXPECT SOME AREAS OF REDUCED
VISIBILITY...ESPECIALLY FOR THOSE AREAS THAT REMAIN MOSTLY CLEAR
FOR A LONGER PERIOD.
AS QUICKLY AS THE STRATUS DEVELOPS...MOST HIGH RESOLUTION MODELS
DISSIPATE IT JUST AS QUICKLY BY LATE MORNING AS 15 TO 20 KTS MIX
WITHIN DEEPENING BOUNDARY LAYER. EXPECT A RETURN TO AT LEAST
PARTLY SUNNY SKIES BY EARLY AFTERNOON. PRIMARY IMPACT OF CLOUDS
WILL BE TO SLOW TEMPERATURE RISE THROUGH THE DAY...SO DROPPED
AFTERNOON HIGHS A FEW DEGREES INTO THE LOWER TO MID 80S.
TONIGHT NOT LIKELY TO BE COMPLETELY CLOUD FREE AND WITH 10 TO 20
KTS ATOP NOCTURNAL INVERSION...FOG THREAT SHOULD BE LOWER THAN THE
PAST COUPLE NIGHTS. TEMPERATURES WILL DROP INTO THE MID TO UPPER
60S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 340 AM CDT MON AUG 31 2015
MAIN STORY FOR THE WEEK CONTINUES TO BE WELL ABOVE NORMAL
TEMPERATURES WITH A BROAD 500 HPA RIDGE PARKED ACROSS THE EASTERN
CONUS. WITH 925 HPA TEMPERATURES GENERALLY WOBBLING BETWEEN 24 AND
26 CELSIUS...DAILY HIGHS HIGHS WILL TOP OUT IN THE MID TO UPPER
80S WITH SOME 90 PLUS DEGREE READINGS ALONG AND EAST OF THE MS
RIVER.
WILL KEEP 20-30 PERCENT MODEL CONSENSUS POPS WEDNESDAY NIGHT
THROUGH FRIDAY...BUT THINK MAJORITY OF THE WEEK WILL REMAIN DRY.
MULTIPLE WEAK/ILL-RESOLVED SHORT-WAVES MOVE ACROSS THE REGION IN
SOUTHWEST FLOW ALOFT THAT COULD PROVIDE A FOCUSING MECHANISM FOR
CONVECTION. HOWEVER...AXIS OF MAXIMUM MID-LEVEL MOISTURE TRANSPORT
REMAINS WEST OF THE FORECAST AREA...CLOSER TO THE WESTERN CONUS
TROUGH. DAILY INSTABILITY IS PRESENT WITH ABOVE NORMAL TEMPERATURES/
SURFACE DEWPOINTS IN THE 60S...BUT LARGE SCALE RIDGE SQUASHES ANY
DEEP LAYER SHEAR OF SIGNIFICANCE. FOR NOW...DIFFICULT TO PROVIDE
DETAILS ON TIMING OR COVERAGE IF ANYTHING DOES DEVELOP SO BROAD-
BRUSHED POPS SEEM REASONABLE.
BETTER CHANCES FOR SHOWERS AND THUNDERSTORMS RETURN SATURDAY NIGHT
INTO SUNDAY AS 31.00Z GFS/ECMWF ATTEMPT TO BREAK DOWN EASTERN
CONUS RIDGE BY MOVING A BROAD PACIFIC TROUGH INTO THE ROCKIES/
NORTHERN PLAINS. GFS IS MUCH QUICKER IN DOING SO COMPARED TO THE
SLOWER ECMWF...SO DEFINITE TIMING ISSUES EMERGE. FOR NOW...A
BLENDED APPROACH IS PRUDENT RESULTING IN CHANCE POPS SATURDAY
NIGHT THROUGH THE DAY ON SUNDAY. SHOULD SEE TEMPERATURES FALL BACK
TO MORE SEASONABLE LEVELS ONCE TROUGH PASSES...BUT WHETHER THIS
OCCURS BY SUNDAY OR EARLY NEXT WEEK IS YET TO BE SEEN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 635 AM CDT MON AUG 31 2015
LIGHT SOUTHERLY FLOW IS BRINGING A MORE HUMID AIR MASS INTO THE
REGION THIS MORNING. THIS WAS PRODUCING EXPANSIVE AREA OF LIFR TO
MVFR STRATUS FROM IOWA INTO SOUTHEAST MN/WESTERN AND NORTHERN WI.
THERE WAS ALSO POCKETS OF VSBY BLO 1SM IN BR. EXPECTING
STRATUS/FOG TO LIFT AND SCATTER OUT LATER THIS MORNING AS
STRONGER SOUTH/SOUTHWEST WINDS MIX OUT THE BOUNDARY LAYER. VFR
CONDITIONS THEN EXPECTED AFTER 16Z. SOUTHERLY AIRFLOW WILL LIKELY
PRODUCE MORE STRATUS TONIGHT ACROSS THE AREA...BUT EXTENT IS NOT
CERTAIN AT THIS TIME. LOOKS LIKE IF CEILINGS DID FORM AT KRST/KLSE
IT WOULD LIKELY BE IN MVFR CATEGORY. SHOULD ALSO SEE SOME LIGHT
FOG WITH VSBY IN THE 5-6SM RANGE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...ROGERS
LONG TERM...ROGERS
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1253 PM CDT MON AUG 31 2015
.UPDATE...
ISSUED AT 1049 AM CDT MON AUG 31 2015
WEAK REMNANTS OF THE BOUNDARY IN THE REGION FROM YESTERDAY
PROVIDING JUST ENOUGH OF A FOCUS FOR SHOWERS AND THUNDERSTORMS
THIS MORNING. SOME INTENSE PRECIPITATION RATES COMBINED WITH
A LACK OF SIGNIFICANT STORM MOTION HAS RESULTED IN HIGH RAINFALL
TOTALS UNDER THE NEARLY STATIONARY STORMS. HAVE HAD TO SENT OUT
UPDATES FOR PRECIP IN THE SOUTHEAST. ENOUGH GAPS IN THE CLOUD
COVER OVER THE SE THAT NO RUSH TO KNOCK DOWN THE MAX TEMPS FOR
TODAY...BUT WILL KEEP AN EYE ON THE AREA. OTHERWISE, A WARM A
MUGGY DAY FOR CENTRAL ILLINOIS.
&&
.SHORT TERM...(TODAY)
ISSUED AT 317 AM CDT MON AUG 31 2015
08Z/3AM SURFACE ANALYSIS SHOWS DISSIPATING FRONTAL BOUNDARY
EXTENDING FROM NORTHERN INDIANA INTO CENTRAL ILLINOIS...GENERALLY
ALONG A FORT WAYNE TO QUINCY LINE. AS WAS THE CASE LAST
NIGHT...QUITE A BIT OF FOG IS DEVELOPING ALONG/NORTH OF THE BOUNDARY
WHERE WINDS ARE NEARLY CALM AND LOW-LEVEL MOISTURE IS ABUNDANT.
LATEST OBS SHOW LOWEST VISBYS CONCENTRATED ALONG THE SOUTHERN SHORE
OF LAKE MICHIGAN ACROSS NORTHERN INDIANA INTO THE CHICAGO AREA.
HRRR HAS BEEN CONSISTENTLY SPREADING THIS THICKER FOG W/SW ALONG THE
FRONT INTO THE NORTHERN KILX CWA OVER THE NEXT COUPLE HOURS...AND AM
BEGINNING TO SEE THIS UNFOLDING WITH VISBY NOW DOWN TO 1/4SM AS FAR
SW AS KIKK. FOLLOWING THE HRRR TREND...WILL MENTION AREAS OF DENSE
FOG ALONG/NORTHEAST OF A GALESBURG TO BLOOMINGTON-NORMAL LINE EARLY
THIS MORNING...WITH PATCHY/AREAS OF FOG ELSEWHERE AROUND THE AREA.
HIGH-RES MODELS SUCH AS THE HRRR AND RAPID REFRESH ARE SUGGESTING
THAT ISOLATED CONVECTION MAY DEVELOP ACROSS SOUTHEAST ILLINOIS OVER
THE NEXT COUPLE OF HOURS. LATEST RADAR IMAGERY IS CLEAR...HOWEVER
SCATTERED MID-LEVEL CLOUDS ARE BEGINNING TO DEVELOP ON IR SATELLITE
IMAGERY ALONG/SOUTH OF I-70...SO HAVE OPTED TO CARRY SLIGHT CHANCE
POPS HERE EARLY THIS MORNING. LATEST WATER VAPOR IMAGERY SHOWS A
SMALL BUT VIGOROUS SHORT-WAVE DROPPING SOUTHWESTWARD FROM NORTHEAST
INDIANA. THIS FEATURE WILL LIKELY INTERACT WITH THE DECAYING FRONT
TO TRIGGER ISOLATED CONVECTION FURTHER NORTH INTO THE CWA THIS
AFTERNOON. MOST MODELS ARE HINTING AT LEAST SOME QPF ACROSS THE
SOUTHERN TWO-THIRDS OF THE AREA...SO HAVE ADDED SLIGHT CHANCE POPS
ALONG/SOUTH OF A JACKSONVILLE TO BLOOMINGTON-NORMAL LINE FOR THE
AFTERNOON.
.LONG TERM...(TONIGHT THROUGH SUNDAY)
ISSUED AT 317 AM CDT MON AUG 31 2015
MAIN WEATHER STORY THROUGH THE EXTENDED WILL BE THE VERY WARM AND
HUMID CONDITIONS THAT ARE EXPECTED TO PERSIST THROUGH EARLY NEXT
WEEK. HIGH TEMPERATURES ON TUESDAY WILL REACH THE UPPER 80S TO
AROUND 90 DEGREES...THEN READINGS WILL CLIMB INTO THE LOWER 90S FOR
THE REMAINDER OF THE PERIOD. DRY WEATHER WILL GENERALLY BE THE
RULE...HOWEVER ISOLATED CONVECTION CANNOT BE RULED OUT...ESPECIALLY
TUESDAY AFTERNOON AS A WEAKNESS IN THE MEAN 500MB RIDGE AXIS REMAINS
IN THE VICINITY. MODELS ARE HINTING AT SOME QPF ACROSS THE E/NE CWA
AS THIS FEATURE GRADUALLY SHIFTS INTO THE GREAT LAKES BY WEDNESDAY.
THE NEXT SIGNIFICANT CHANCE FOR RAIN WILL NOT ARRIVE UNTIL EARLY
NEXT WEEK...WHEN A STRONG SHORT-WAVE FLATTENS THE UPPER RIDGE AND
PUSHES A COLD FRONT INTO THE REGION. MODELS ARE IN DISAGREEMENT
CONCERNING THE SPEED OF THIS PROCESS...WITH THE GFS BEING ABOUT 24
HOURS FASTER THAN THE ECMWF/GEM. THE 00Z AUG 31 GFS SHOWS THE COLD
FRONT PASSING THROUGH CENTRAL ILLINOIS LATE SUNDAY NIGHT INTO
MONDAY...WHILE THE ECMWF/GEM HAVE DELAYED FROPA UNTIL LATE MONDAY
NIGHT INTO TUESDAY. GIVEN PERSISTENT AND HIGHLY AMPLIFIED RIDGE
POSITIONED ACROSS THE MIDWEST...THINK A SLOWER BREAK DOWN TO THE
PATTERN IS PRUDENT. HAVE THEREFORE TRENDED THE FORECAST TOWARD THE
SLOWER ECMWF/GEM CONSENSUS. AS A RESULT...AM EXPECTING DRY
CONDITIONS THROUGH SUNDAY NIGHT...WITH HIGHER RAIN CHANCES ARRIVING
BY LATE MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1235 PM CDT MON AUG 31 2015
CU FIELD AND SOME CIRRUS TODAY WITH THE CIGS LINGERING AT THE
MVFR/VFR BREAK. PIA MORE LIKELY TO BE IN THE SCT TERRITORY, AND A
COLD POOL FROM THIS MORNINGS CONVECTION IN THE SOUTHEAST HAS
SCOURED OUT THE VERTICAL GROWTH FOR CMI. LIGHT SOUTHERLY WINDS
OVERNIGHT, VEERING TO MORE SOUTHWESTERLY BY MORNING. BIGGER ISSUE
FOR THE OVERNIGHT WILL BE THE POTENTIAL FOR FOG DEVELOPMENT.
ALTHOUGH LAST NIGHT WAS MORE SCATTERED, DEWPOINTS ARE IN THE LOWER
70S, SEVERAL DEGREES ABOVE THIS TIME YESTERDAY IN MANY LOCATIONS.
HAVE DROPPED TEMPO TO 1SM FOR NOW KEEPING IT TO IFR PREDAWN.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HJS
SHORT TERM...BARNES
LONG TERM...BARNES
AVIATION...HJS
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1243 PM CDT MON AUG 31 2015
.UPDATE...
ISSUED AT 1243 PM CDT MON AUG 31 2015
MINOR UPDATE...KEEP SLIGHTLY MORE CLOUD COVER OVER THE WEST THOUGH
AREA SHOULD MIX OUT TO SCT BY MID TO LATE AFTERNOON. ALSO RAISED
TMAX ABOUT 2 DEGREES OVER THE WEST/CENTRAL/SOUTHEAST AS
TEMPERATURES CONTINUE TO CLIMB NOW THAT THE LOWER CLOUDS HAVE
DEPARTED./REV
UPDATE ISSUED AT 646 AM CDT MON AUG 31 2015
VISIBILITIES NEVER DETERIORATED AS EXPECTED OVER MUCH OF SOUTHERN
AND EAST CENTRAL IOWA...ONLY DOWN TO A FEW MILES AT WORST...SO THE
PREVIOUS ADVISORY HAS BEEN CANCELLED. LOW VISIBILITIES DO CONTINUE
IN AREAS OVER THE NORTHERN HALF OF IOWA HOWEVER...BUT THEY ARE
EXPECTED TO IMPROVE SHORTLY.
&&
.SHORT TERM /TODAY/...
ISSUED AT 320 AM CDT MON AUG 31 2015
MUCH LIKE YESTERDAY...THE MAIN CONCERNS ARE TEMP AND VISIBILITY
TRENDS. STRATUS COVERAGE IS LESS THAN LAST NIGHT WITH ONLY SOME
TOKEN CIRRUS NW. THIS WOULD SUGGEST A MORE UNIFORM RADIATION FOG
DEVELOPMENT BUT THAT HAS NOT BEEN THE CASE WITH VISIBILITIES
SOMEWHAT VARIABLE. EVEN THOUGH SRN IA WAS HIT HARDEST WITH DENSE FOG
LAST NIGHT AND CONDITIONS ARE SIMILAR...VISIBILITIES HAVE NOT REALLY
DROPPED MUCH IN THE ADVISORY AREA. RAP 1000-950MB RH IS ACTUALLY
RELATIVELY LOWER IN THIS AREA SO ADVISORY CONFIDENCE IS NOT GREAT.
HOWEVER CONFIDENCE IS EQUALLY NOT GREAT THAT CONDITIONS WILL NOT
TANK IN THE NEXT SEVERAL HOURS EITHER SO WILL LEAVE HEADLINE AS IS
AND EVALUATE HOURLY FOR NEEDED CHANGES. LOWEST VISIBILITIES ARE
ACTUALLY NORTH SO WILL GO WITH KEEPING HEADLINE AND SPS OTHER AREAS
FOR NOW.
TEMPS WILL BE PROBLEMATIC ONCE AGAIN. MODEL SOUNDINGS ARE SOMEWHAT
MORE AGGRESSIVE WITH MIXING POTENTIAL...WHICH MAKES SOME SENSE WITH
WINDS A TAD HIGHER AND LESS STRATUS AROUND. HOWEVER IS HAS BEEN
DIFFICULT WARMING TOO MUCH OVER THE PAST FEW WEEKS...ESPECIALLY TO
GFS EXPECTATIONS WHICH HAS SHOWN AND WARM BIAS. COOLER NAM MOS HAS
BEEN BETTER RECENTLY AND WILL CONTINUE TO FOLLOW THAT LEAD. THIS
RESULTS IN TRIMMING PREVIOUS FORECAST SEVERAL DEGREES.
.LONG TERM /TONIGHT THROUGH SUNDAY/...
ISSUED AT 320 AM CDT MON AUG 31 2015
THE FORECAST FOR THIS WEEK REMAINS WARM AND MOSTLY DRY. A DEEP
LAYER RIDGE BLANKETING THE SOUTHERN U.S. WILL GRADUALLY PIVOT
AROUND OVER THE EASTERN U.S. AS A LONGWAVE TROUGH STEADILY DIGS
DOWN THE WEST COAST. THIS WILL PLACE IOWA BENEATH THE PROVERBIAL
RING OF FIRE FOR SEVERAL DAYS THIS WEEK...HOWEVER...THE SUBTLE
SHORTWAVES MOVING THROUGH THE STEERING FLOW ALOFT WILL BE FAIRLY
WEAK AND DIFFICULT TO PIN DOWN IN TERMS OF TIMING. WILL MAINTAIN
LOW 20 TO 30 POPS AT TIMES DURING THE WORK WEEK...MAINLY ACROSS
THE NORTHWEST HALF OF THE FORECAST AREA...BUT ANY STORMS SHOULD BE
OF LITTLE IMPACT. MEANWHILE TEMPERATURES WILL CLIMB WELL INTO THE
80S EACH DAY GIVEN THE WARM TEMPERATURES ALOFT...MODEST SOUTH TO
SOUTHWEST LOW LEVEL FLOW...AND MOSTLY SUNNY SKIES FORECAST.
LATER IN THE WEEK...FROM ABOUT THURSDAY THROUGH SATURDAY...THE
DEEPENING WESTERN TROUGH WILL SHUNT THE LARGE SOUTHERN RIDGE OVER
TOWARD THE APPALACHIANS AND RESULT IN ANY SUBTLE SHORTWAVES
EJECTING OUT OF THE TROUGH MOVING MORE NORTHEASTWARD ACROSS THE
HIGH PLAINS AND MINNESOTA. THIS RESULTS IN A PERIOD OF LOWER POPS
BUT SLIGHTLY HIGHER TEMPERATURES AS ANY STORMS THAT FORM SHOULD
RANGE FROM NEBRASKA UP ACROSS THE DAKOTAS AND THE WARM AIRMASS TO
OUR SOUTHEAST WILL ENCROACH A BIT MORE INTO IOWA BY THE END OF THE
WEEK. THE WEST COAST TROUGH WILL EVENTUALLY KICK OUT ACROSS THE
CENTRAL U.S. AND PUSH A COLD FRONT ACROSS OUR REGION...GENERATING
MORE WIDESPREAD SHOWERS AND THUNDERSTORMS FOLLOWED BY COOLER
WEATHER. HOWEVER...THERE CONTINUES TO BE A CONSIDERABLE AMOUNT OF
SPREAD AMONG THE LONG RANGE MODELS IN THEIR SOLUTIONS FOR THIS
EVOLUTION AND PARTICULARLY THE TIMING OF RAIN AND FRONTAL PASSAGE
FOR IOWA. HAVE THUS STUCK CLOSE TO MODEL CONSENSUS WITH RAIN
CHANCES MOSTLY IN THE SUNDAY/SUNDAY NIGHT TIME FRAMES AND COOLER
WEATHER LIKELY BY NEXT MONDAY. THESE DETAILS WILL GRADUALLY COME
INTO FOCUS LATER THIS WEEK.
&&
.AVIATION...31/18Z
ISSUED AT 1243 PM CDT MON AUG 31 2015
SIMILAR CONCERNS OF PAST FEW NIGHTS...ABUNDANT LOW LEVEL MOISTURE
WITH LIGHT WINDS OVERNIGHT. AS UPPER LEVEL TROUGH AND SFC
REFLECTION BOTH REMAIN NORTHWEST OF THE AREA TONIGHT/TUE
MORNING...WILL EXPECT TO SEE BR/POSSIBLE FG AGAIN DEVELOP AFT 06Z.
HAVE NOT HIT TERMINALS AS HARD WITH VSBY AS AIRMASS CONTINUES TO
WARM WHICH SHOULD OFFSET POTENTIAL FOR WIDESPREAD THICK FOG. NONE
THE LESS...HAVE LOWERED A FEW SPOTS TO 1SM...2SM BY 09-12Z. LIKELY
THE LAYER WILL BE SHALLOWER THAN PAST NIGHTS THOUGH SOME
UNCERTAINTY WITH THAT. 00Z/06Z PACKAGES SHOULD HAVE A BETTER IDEA
OF DETAILS. OTHERWISE...WIND OF LITTLE CONCERN THOUGH SOME MIXING
EXPECTED WEST TODAY/TOMORROW.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...REV
SHORT TERM...SMALL
LONG TERM...LEE
AVIATION...REV
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
102 PM EDT MON AUG 31 2015
...UPDATED AVIATION DISCUSSION...
...FORECAST UPDATE...
ISSUED AT 1155 AM EDT MON AUG 31 2015
GOES SOUNDER DATA INDICATE PRECIPITABLE WATER LEVELS ARE AROUND 1.3
INCHES...QUITE A BIT LESS THAN THIS TIME YESTERDAY. AMDAR SOUNDINGS
SHOW A PRETTY GOOD CAP AT 500 MB. LATEST RUC SOUNDINGS SHOW MORE PW
THAN WHAT THE GOES SOUNDER HAS. WITH THE DRYING OUT...MULTIPLE
MODELS SHOW LITTLE IN THE WAY OF PRECIP. DECIDED TO BACK OFF ON POPS
FOR ALL BUT OUR NORTHERN STRIPE OF COUNTIES IN INDIANA. REST OF THE
FORECAST LOOKS GOOD WITH LOUISVILLE METRO GETTING TO THE UPPER 80S
AND THE REST OF THE AREA IN THE MID 80S.
.SHORT TERM (NOW THROUGH TUESDAY)...
ISSUED AT 315 AM EDT MON AUG 31 2015
EARLY THIS MORNING SOME PATCHY FOG HAS DEVELOPED IN SPOTS. THINK WE
MAY SEE MORE DEVELOP ESPECIALLY IN AREAS THAT RECEIVED RAINFALL
YESTERDAY, SO WILL CONTINUE EARLY MORNING PATCHY FOG MENTION BUT
DON`T THINK FOG SHOULD BECOME DENSE OR WIDESPREAD. FOG SHOULD
DIMINISH SHORTLY AFTER SUNRISE.
FOR THE REST OF THE DAY, EXPECT PARTLY CLOUDY SKIES WITH ISOLATED
AFTERNOON/EVENING SHOWERS/STORMS DEVELOPING AGAIN. RIDGING WILL BE
ON THE INCREASE TODAY AND INHIBIT CONVECTION COVERAGE A LITTLE MORE
THAN YESTERDAY. THE MOST LIKELY LOCATIONS TO SEE AN ISLD SHOWER OR
STORM LOOK TO BE SOUTHERN INDIANA OR NORTH CENTRAL KY WHERE CAPPING
MAY BE WEAKER. EXPECT HIGH TEMPS TO BE SIMILAR TO YESTERDAY IN THE
MIDDLE 80S.
TONIGHT IS EXPECTED TO BE MAINLY DRY WITH ANY CONVECTION ENDING
DURING THE EVENING HOURS. RIDGING WILL CONTINUE TO INCREASE OVER
THE REGION WITH A GOOD MID LEVEL CAP NOTED IN SOUNDINGS FOR TUESDAY.
THEREFORE WILL KEEP TUES DRY. LOWS TONIGHT SHOULD RANGE FROM THE
MID 60S TO AROUND 70. HIGHS ON TUES WILL WARM INTO THE UPPER 80S TO
AROUND 90.
.LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)...
ISSUED AT 258 AM EDT MON AUG 31 2015
THE MAIN STORY FOR THE LONG TERM PERIOD IS THE LIKELY HOT AND DRY
CONDITIONS AS WE HEAD INTO THE FIRST FULL WEEK OF SEPTEMBER AND THE
UPCOMING HOLIDAY WEEKEND.
THE 31.00Z GUIDANCE TRENDED TOWARD SIMILAR SOLUTIONS WITH REGARD TO
THE UPPER LEVEL PATTERN...SHOWING BUILDING HEIGHTS AND RIDGING
WEDNESDAY THROUGH THIS UPCOMING WEEKEND. AT THE SURFACE...THE REGION
WILL BE MOSTLY UNDER THE INFLUENCE OF HIGH PRESSURE.
SENSIBLE WEATHER INCLUDES SEASONABLY WARM TO HOT CONDITIONS AS
READINGS TOP OUT IN THE UPPER 80S TO LOW 90S EACH AFTERNOON. LOOKING
AT SOME OF THE EXTENDED ENSEMBLE MOS DATA...THURSDAY THROUGH
SATURDAY LOOK TO BE THE WARMEST...AND A FEW MID 90 READINGS ARE
POSSIBLE IN THE TYPICAL WARM SPOTS AND URBAN CORES THOSE DAYS. PLAN
ON MILD TO MUGGY MORNINGS WITH READINGS IN THE UPPER 60S TO LOW 70S.
A WEAK CAP AND SUBSIDENCE ALOFT SHOULD PRECLUDE THE DEVELOPMENT OF
AFTERNOON/EVENING SHOWERS FOR THE MAJORITY OF FOLKS MOST
DAYS...HOWEVER GIVEN THE WARM TEMPERATURES AND MODEST DEWPOINTS
/MID 60S/...COULDN`T RULE OUT A STRAY SHOWER OR STORM. FOR
CONTINUITY...KEPT A VERY SLIGHT CHANCE IN THE FORECAST FOR SOUTHERN
INDIANA AND NORTHERN KENTUCKY WEDNESDAY. BY THIS WEEKEND...A MODEL
CONSENSUS SHOWS SLIGHT CHANCES OF SHOWER/STORMS...THOUGH WITH NO
REAL FORCING MECHANISM OR STRONG MOISTURE TRANSPORT THIS MAY BE
OVERDONE. A CONTINUATION OF DRY WEATHER COULD CONTINUE THROUGH
SUNDAY.
&&
.AVIATION (18Z TAF UPDATE)...
ISSUED AT 100 PM EDT MON AUG 31 2015
QUITE WEATHER EXPECTED AT THE TERMINALS THIS PERIOD. ONLY EXCEPTION
MAY BE SOME BRIEF REDUCTIONS IN VSBY AT KBWG/KLEX. ONLY HAVE ENOUGH
CONFIDENCE TO PUT IN A TEMPO GROUP AT KBWG. WILL WAIT AND SEE HOW
DRY THE AFTERNOON GETS AT KLEX BEFORE DEALING WITH THAT POTENTIAL
LATER.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
UPDATE.........RJS
SHORT TERM.....AMS
LONG TERM......ZBT
AVIATION.......RJS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
426 PM EDT MON AUG 31 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 418 PM EDT MON AUG 31 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A PROMINENT MID/UPEPR LEVEL
RIDGE FROM NM INTO THE GREAT LAKES RESULSTING IN SW FLOW FROM THE
CNTRL ROCKIES INTO THE UPPER MS VALLEY. A WELL-DEFINED SHORTWAVE
TROUGH OVER SRN MANITOBA WAS LIFTING TO THE NE. AT THE SFC...SSW
FLOW PREAVILED ACROSS THE UPPER MS VALLEY AND WRN ALKES BETWEEN HIGH
PRES OVER THE CNTRL LAKES AND A COLD FRONT EXTENDING FROM THE SE
CORNER OF MANITOBA INTO ERN SD. MOST OF THE FOG FROM EARLIER TODAY
HAS BURNED OFF EXCEPT OVER THE FAR SE ALONG LAKE MI NEAR KISQ.
OTHERWISE...MOSTLY SUNNY SKIES PREVAILED WITH TEMPS AWAY FROM LAKE
MI INTO THE MID TO UPPER 80S.
TONIGHT...SEVERAL MODELS SUGGEST SOME SHRA/TSRA MAY DEVELOP FROM MN
INTO NW WI OR WRN LAKE SUPEROR AS AN AXIS OF HIGHER MOISTURE AND THE
TAIL OF THE MANITOBA SHRTWV SLIDES TO THE EAST. HOWEVER...THE AMOUNT
OF CAPPING AND ONLY WEAK MID LEVEL QVECTOR CONV...EXPECT ANY
COVERAGE TO BE MINIMAL AND REMAIN TO THE WEST OF THE CWA. ALTHOUGH
BNDRY LAYER WINDS WILL BE HIGHER THAN LAST NIGHT...EXPECT PATCHY/AREAS
TO REDEVELOP OVER MAINLY THE SE HALF.
TUE...PCPN CHANCES WILL INCREASE AS THE MOISTURE AXIS AND WEAK
TROUGH SAG INTO UPPER MICHIGAN. ALTHOUGH SOME PCPN MAY BE POSSIBLE
IN THE MORNING...EXPECT BETTER SHRA/TSRA CHANCES BY AFTERNOON WITH
INCREASED DAYTIME HEATING AND SUPPORT FROM DEVELOPING LAKE BREEZE
BOUNDARIES. TSRA WILL BE POSSIBLE WITH MLCAPE VALUES INTO THE 1K-2K
J/KG RANGE. HOWEVER WITH 0-6KM SHEAR VALUES ONLY AROUND 25-30 KNOTS
AND WITH WBZ HEGHTS NEAR 13K FT...SEVERE TS CHANCES WILL BE MINIMAL.
THE MAIN HAZARDS WILL BE BRIEF HEAVY RAIN AND GUSTY WINDS. EVEN WITH
INCREASED CLOUD COVER...TEMPS SHOULD AGAIN CLIMB INTO THE MID TO
UPPER 80S.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 426 PM EDT MON AUG 31 2015
MORE 80S ARE ON THE WAY THROUGH AT LEAST SATURDAY. THE 500MB RIDGE
SET UP FROM W TX-LOWER MI...EXTENDING UP THROUGH HUDSON BAY WILL
FLATTEN OUT ONLY SLIGHTLY...BEFORE REBOUNDING OVER THE UPPER GREAT
LAKES WEDNESDAY NIGHT THROUGH AT LEAST SATURDAY.
WE WILL HAVE A LONG STRETCH OF TEMPERATURES AT OR ABOVE
80F...PROBABLY 8 DAYS IN TOTAL. IT WILL LIKELY END UP THE LONGEST
STRETCH IN 2 YEARS...AND TIED FOR THE LONGEST STRETCH IN 9 YEARS.
THE LAST TIME WE HAD MORE THAN 7 DAYS IN A ROW WAS IN 2006.
ALTHOUGH A NEARING SFC TROUGH TUESDAY NIGHT WILL KEEP LOW POPS OVER
MAINLY E LAKE SUPERIOR...IT WILL WILL HAVE TO OVERCOME PLENTY OF DRY
AIR. PW VALUES DO INCREASE TO 1.7 TO NEAR 2IN E.
ANY WIDESPREAD PRECIP WILL LIKELY HOLD OFF UNTIL SUNDAY OR EVEN
SUNDAY NIGHT UNTIL MONDAY. THE GFS IS A BIT SLOWER THAN THEN ECMWF.
THE APEX OF THE 500MB RIDGE WILL SHIFT W ACROSS THE LOWER GREAT
LAKES AND NEW ENGLAND STATES FOR THE LATTER HALF OF THE
WEEKEND...WITH SW FLOW MOVING INTO OUR AREA. TIMING OF THE NEXT
500MB LOW OR SIGNIFICANT WAVE EJECTING OUT OF THE W TROUGH IS STILL
UNCERTAIN. HOWEVER...INITIAL LOOKS SHOW THAT NEXT TUESDAY OR
WEDNESDAY COULD GIVE US A BETTER CHANCE OF SOME COOLER
AIR...ALTHOUGH IT MAY BE SHORT LIVED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 741 AM EDT MON AUG 31 2015
PATCHY GROUND FOG IS AFFECTING KSAW/KCMX AT THE START OF THE TAF
PERIOD...BUT STRONGER WINDS ALOFT AND DIURNAL HEATING SHOULD
QUICKLY DISSIPATE THE FOG THIS MORNING. OTHERWISE...EXPECT VFR
CONDITIONS TO PREVAIL AT THE SITES THROUGH MUCH OF THE REST OF THE
PERIOD. A WEAK TROUGH WILL NEAR THE WESTERN SITES LATE TONIGHT AND
COULD PRODUCE SOME SPRINKLES...WITH KSAW ONCE AGAIN SEEING THE
POTENTIAL FOR PATCHY GROUND FOG (ALTHOUGH WINDS ABOVE THE SURFACE
WILL BE A TOUCH STRONGER).
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 418 PM EDT MON AUG 31 2015
EXPECT SOUTH-SOUTHWESTERLY WINDS TO CONTINUE OVER LAKE SUPERIOR
THROUGH MUCH OF THE WEEK...AS THE AREA IS ON THE NORTHWESTERN EDGE
OF A HIGH PRESSURE RIDGE CENTERED OVER THE CENTRAL APPALACHIANS.
THERE WILL BE A BRIEF INCREASE IN THE SOUTHWESTERLY WINDS
TONIGHT...UP TO 20KTS...AS A LOW PRESSURE SYSTEM MOVES THROUGH NW
ONTARIO TO SOUTHERN HUDSON BAY BY TUE MORNING. AT THIS TIME...THE
MARINE LAYER SHOULD KEEP THE WINDS IN CHECK...BUT COULD SEE HIGHER
GUSTS TO 25 OR EVEN 30KTS AT A FEW OF THE HIGHER PLATFORMS TOWARDS
ISLE ROYALE. OTHERWISE...EXPECT WINDS TO BE BELOW 20KTS FOR THE REST
OF THE PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...SRF
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
421 PM EDT MON AUG 31 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 418 PM EDT MON AUG 31 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A PROMINENT MID/UPEPR LEVEL
RIDGE FROM NM INTO THE GREAT LAKES RESULSTING IN SW FLOW FROM THE
CNTRL ROCKIES INTO THE UPPER MS VALLEY. A WELL-DEFINED SHORTWAVE
TROUGH OVER SRN MANITOBA WAS LIFTING TO THE NE. AT THE SFC...SSW
FLOW PREAVILED ACROSS THE UPPER MS VALLEY AND WRN ALKES BETWEEN HIGH
PRES OVER THE CNTRL LAKES AND A COLD FRONT EXTENDING FROM THE SE
CORNER OF MANITOBA INTO ERN SD. MOST OF THE FOG FROM EARLIER TODAY
HAS BURNED OFF EXCEPT OVER THE FAR SE ALONG LAKE MI NEAR KISQ.
OTHERWISE...MOSTLY SUNNY SKIES PREVAILED WITH TEMPS AWAY FROM LAKE
MI INTO THE MID TO UPPER 80S.
TONIGHT...SEVERAL MODELS SUGGEST SOME SHRA/TSRA MAY DEVELOP FROM MN
INTO NW WI OR WRN LAKE SUPEROR AS AN AXIS OF HIGHER MOISTURE AND THE
TAIL OF THE MANITOBA SHRTWV SLIDES TO THE EAST. HOWEVER...THE AMOUNT
OF CAPPING AND ONLY WEAK MID LEVEL QVECTOR CONV...EXPECT ANY
COVERAGE TO BE MINIMAL AND REMAIN TO THE WEST OF THE CWA. ALTHOUGH
BNDRY LAYER WINDS WILL BE HIGHER THAN LAST NIGHT...EXPECT PATCHY/AREAS
TO REDEVELOP OVER MAINLY THE SE HALF.
TUE...PCPN CHANCES WILL INCREASE AS THE MOISTURE AXIS AND WEAK
TROUGH SAG INTO UPPER MICHIGAN. ALTHOUGH SOME PCPN MAY BE POSSIBLE
IN THE MORNING...EXPECT BETTER SHRA/TSRA CHANCES BY AFTERNOON WITH
INCREASED DAYTIME HEATING AND SUPPORT FROM DEVELOPING LAKE BREEZE
BOUNDARIES. TSRA WILL BE POSSIBLE WITH MLCAPE VALUES INTO THE 1K-2K
J/KG RANGE. HOWEVER WITH 0-6KM SHEAR VALUES ONLY AROUND 25-30 KNOTS
AND WITH WBZ HEGHTS NEAR 13K FT...SEVERE TS CHANCES WILL BE MINIMAL.
THE MAIN HAZARDS WILL BE BRIEF HEAVY RAIN AND GUSTY WINDS. EVEN WITH
INCREASED CLOUD COVER...TEMPS SHOULD AGAIN CLIMB INTO THE MID TO
UPPER 80S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 428 AM EDT MON AUG 31 2015
NO BIG CHANGES TO THE OVERALL IDEA OF LATE SUMMER RIDGING DOMINATING
INTO NEXT WEEKEND. TROUGHING ALOFT WITH MUCH COOLER CONDITIONS STILL
ON TRACK TO ARRIVE AROUND LABOR DAY.
RIDGE ALOFT FLATTENS OUT SLIGHTLY TUE INTO WED WHICH ALLOWS WEAK
SHORTWAVES TO CROSS THE REGION AND AT LEAST SOME CHANCES OF RAIN.
STRONGEST WAVE BY FAR STAYS OVER NORTHERN ONTARIO WITH ASSOCIATED
SFC LOW...BUT THERE IS STILL HINT FM MODELS THAT TAIL OF THAT
SHORTWAVE OR ADDITIONAL MINOR WAVES LIFTING IN FM THE
SOUTHWEST...AND ASSOCIATED SUBTLE H7-H5 Q-VECTOR CONVERGENCE WILL
COMBINE WITH WEAK SFC TROUGH AND LAKE BREEZES TO DEVELOP A FEW
SHRA/TSRA. WITH HEIGHTS LOWERING ALSO CANNOT DISCOUNT IDEA SHOWN BY
NAM/GEM-REGIONAL THAT ISOLD SHRA COULD WORK IN AS EARLY AS THE
MORNING AS WEAK SHORTWAVES SLIDING THROUGH COMBINE WITH MOISTURE
ADVECTION AT H85. GEM-REGIONAL SHOWS QPF OVER KEWEENAW 12Z-15Z WHICH
IS ALSO SUPPORTED BY LATEST NCAR ENSEMBLES. OVERALL THOUGH...LACKING
DEEPER MOISTURE AS SEEN IN FORECAST SOUNDINGS WILL BE LIMITING
FACTOR FOR MUCH PRECIP. TSRA CHANCES PROBABLY TOP OUT DURING PEAK
HEATING OF DAY...BUT WITH 1-6KM MUCAPE OVER 500J/KG POKING IN OVER
WESTERN CWA IN THE MORNING...CANNOT COMPLETELY RULE OUT. IF A TSRA
COULD FORM...ESPECIALLY DURING PEAK HEATING OF AFTN...COULD SEE AN
ISOLD STRONGER STORM WITH MLCAPES TO AROUND 1000J/KG AND DEEP LAYER
SHEAR 30+ KTS. SMALL DCAPES AND WBZERO HEIGHTS TO 12KFT WOULD SUPPORT
ONLY A MARGINAL HAIL RISK. LIGHTNING AND HEAVY DOWNPOURS WOULD BE
MAIN HAZARDS. STORM MOTION WOULD BE FM WEST TO EAST AT 25-30 KTS.
BASED ON H85 TEMPS AROUND 18C WILL GO FOR HIGHS IN THE MID 80S...DOWN
SOME FM THE LOW 90S FORECAST TODAY.
WEAKNESS IN RIDGE STILL THERE FOR WED AND WED NIGHT SO MAY SEE
ANOTHER OPPORTUNITY FOR SOME SHRA/TSRA. WEAK LARGE SCALE SUPPORT AND
MARGINAL MOISTURE WILL CONTINUE TO LIMIT COVERAGE. BEST CHANCE OF
SHRA/TSRA SHOULD BE DURING PEAK HEATING ON WED AFTN. THEN INTO WED
NIGHT...BASED ON ITS OWN FORECAST SOUDNINGS...LAST COUPLE RUNS OF
GFS SEEM TOO AMBITIOUS SHOWING WIDESPREAD LIGHT QPF IN ARC FM CNTRL
MANITOBA/NORTHWEST ONTARIO TO THE UPPER GREAT LAKES. SOUNDINGS SHOW
A LOT OF DRY AIR BLO H6 AND THE MID LEVEL RH SUGGESTS MAYBE BKN
CLOUDS BUT NOT A LOT OF PRECIP. WILL FOLLOW THE DRIER NAM/GEM-
NH/ECMWF WITH ONLY SCATTERED MID CLOUDS. HEAT CONTINUES WITH
READINGS ON WED REACHING BACK TOWARD 90 DEGREES OVER WEST AND MID-
UPR 80S ELSEWHERE AWAY FM LK MICHIGAN. DEVELOPING SSE WINDS WILL
KEEP IMMEDIATE LAKE SUPERIOR SHORE FM KEWEENAW TO BIG BAY/MARQUETTE
A SHADE COOLER.
SHORTWAVE WORKING ACROSS UPPER GREAT LAKES THURDAY APPEARS TO STAY
SOUTH OF UPR MICHIGAN AT LEAST RIGHT NOW. CHANCES OF SHRA/TSRA WILL
BE LOW...BUT WILL KEEP SLIGHT CHANCES DURING PEAK HEATING ON THU
AFTN. TEMPS ON THU MID 80S TO NEAR 90...SIMILAR TO READINGS ON WED
WITH MINIMAL CHANGE IN H85 TEMPS OF 18-20C. UPPER RIDGE BUILDS BACK
OVER GREAT LAKES ON FRIDAY SO ANY SHORTWAVES WORKING THROUGH BY THAT
TIME SHOULD BE WEAK. WITHOUT MUCH LARGE SCALE SUPPORT...SHRA/TSRA
SHOULD BE TIED TO EDGE OF STRONGEST INSTABILITY EXPANDING FM THE
PLAINS. REMNANTS OF THIS ACTIVITY MAY TRY TO MAKE IT OVER UPPER
GREAT LAKES LATER FRIDAY INTO SATURDAY. TIME FRAME SEEMS LIKE IT
WILL END UP MOSTLY DRY THOUGH. HIGH TEMPS SIMILAR TO WED AND THU.
GFS AND ECMWF/GEM-NH SHOW DIFFERENCES FOR THE UPCOMING WEEKEND.
MAIN ISSUE IS HOW QUICKLY COLD FRONT THAT USHERS IN MUCH COOLER
CONDITIONS WILL ARRIVE. AS THE FRONT DRAWS CLOSER MAY SEE BETTER
CHANCES OF SHRA/TSRA OVER AT LEAST WESTERN CWA ON SATURDAY. HEAT
CONTINUES WITH HIGHS AGAIN UPR 80S TO AROUND 90 DEGREES. GFS HAS
BACKED AWAY FM THE 22-24C H85 TEMPS IT SHOWED YDY...SO PROBABLY
LOOKING AT MAX TEMPS INTO THE LOWER 90S AT THE WARMEST. GFS MUCH
QUICKER SHOWING FRONT MOVING THROUGH ON SUNDAY WHILE ECMWF IS
STRONGER WITH UPPER RIDGE AND DOES NOT BRING THE FRONT THROUGH
UNTIL MONDAY. TYPICALLY THE STRONGER RIDGE WINS OUT. AT THIS POINT
WILL NOT STRAY FM MODEL CONSENSUS WHICH RESULTS IN LOW CHANCE POPS
FOR SUNDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 741 AM EDT MON AUG 31 2015
PATCHY GROUND FOG IS AFFECTING KSAW/KCMX AT THE START OF THE TAF
PERIOD...BUT STRONGER WINDS ALOFT AND DIURNAL HEATING SHOULD
QUICKLY DISSIPATE THE FOG THIS MORNING. OTHERWISE...EXPECT VFR
CONDITIONS TO PREVAIL AT THE SITES THROUGH MUCH OF THE REST OF THE
PERIOD. A WEAK TROUGH WILL NEAR THE WESTERN SITES LATE TONIGHT AND
COULD PRODUCE SOME SPRINKLES...WITH KSAW ONCE AGAIN SEEING THE
POTENTIAL FOR PATCHY GROUND FOG (ALTHOUGH WINDS ABOVE THE SURFACE
WILL BE A TOUCH STRONGER).
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 418 PM EDT MON AUG 31 2015
EXPECT SOUTH-SOUTHWESTERLY WINDS TO CONTINUE OVER LAKE SUPERIOR
THROUGH MUCH OF THE WEEK...AS THE AREA IS ON THE NORTHWESTERN EDGE
OF A HIGH PRESSURE RIDGE CENTERED OVER THE CENTRAL APPALACHIANS.
THERE WILL BE A BRIEF INCREASE IN THE SOUTHWESTERLY WINDS
TONIGHT...UP TO 20KTS...AS A LOW PRESSURE SYSTEM MOVES THROUGH NW
ONTARIO TO SOUTHERN HUDSON BAY BY TUE MORNING. AT THIS TIME...THE
MARINE LAYER SHOULD KEEP THE WINDS IN CHECK...BUT COULD SEE HIGHER
GUSTS TO 25 OR EVEN 30KTS AT A FEW OF THE HIGHER PLATFORMS TOWARDS
ISLE ROYALE. OTHERWISE...EXPECT WINDS TO BE BELOW 20KTS FOR THE REST
OF THE PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...SRF
MARINE...JLB
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1220 PM CDT MON AUG 31 2015
.UPDATE...
ISSUED AT 1203 PM CDT MON AUG 31 2015
THE FOG HAS DISSIPATED EXCEPT ALONG THE NORTH SHORE FROM TACONITE
HARBOR TO GRAND PORTAGE. THE STRATUS IS HANGING ON IN NW WI...BUT
SOME IMPROVEMENT IS OCCURRING. HAZY SUNSHINE ELSEWHERE DUE TO
SMOKE FROM WESTERN U.S. WILDFIRES. COLD FRONT IN NW MN HAS MADE
LITTLE PROGRESS EWD...ALTHOUGH SOME CLOUDS ARE MOVING TOWARD
KOOCHICHING COUNTY. HAVE ADJUSTED FOR THESE TRENDS.
UPDATE ISSUED AT 915 AM CDT MON AUG 31 2015
A COLD FRONT WAS DRAPED OVER EASTERN ND AND THE EXTREME CORNER OF NW
MN AT 14Z. THUNDERSTORMS WERE OCCURRING BEHIND THE FRONT IN NE ND
AND LIFTING NEWD INTO CANADA. SOUTHERLY FLOW OVER THE FORECAST
AREA HAS LED TO A STRATUS DECK OVER NW WI AND ADJACENT MN AND
ALONG THE NORTH SHORE OF LAKE SUPERIOR WITH SOME FOG THAT WAS
SLOWLY LIFTING. EXPECT THE STRATUS AND FOG TO CONTINUE TO ERODE
THIS MORNING AND HAVE ADJUSTED FOR THIS TREND. WITH THE STORMS
MOVING INTO CANADA AND LATEST HRRR INDICATING NO STORMS INTO THE
REGION THROUGH THE AFTERNOON FOR THE LAST FEW RUNS. HAVE REMOVED
THE MENTION OF STORMS TODAY.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 240 AM CDT MON AUG 31 2015
AN UPPER RIDGE WILL MOVE EAST OF THE REGION TODAY WITH SOUTHERLY
SURFACE FLOW KEEPING HIGHER DEWPOINTS IN PLACE. A COLD FRONT WILL
MOVE INTO FAR WESTERN MINNESOTA BY LATE AFTERNOON/EARLY EVENING
AND PROGRESS INTO NORTHEAST MINNESOTA TONIGHT BEFORE WEAKENING
TUESDAY.
STRATUS AND SOME PATCHY FOG HAVE ONCE AGAIN FORMED ACROSS
NORTHERN WISCONSIN AND PORTIONS OF NORTHEAST MINNESOTA THIS
MORNING. THE STRATUS/FOG SHOULD BURN OFF THIS MORNING AND THE RAP
SEEMS TO BE HANDLING THIS DECENTLY. CLOUDS WILL DIMINISH THROUGH
THE MORNING...THEN INCREASE AGAIN OVER WESTERN AREAS THIS
AFTERNOON AHEAD OF THE COLD FRONT. WE KEPT A MENTION OF
SHOWERS/STORMS IN THE WEST LATE TODAY...THEN PROGRESS THE CHANCE
EAST TONIGHT. THE NAM/GFS/ECMWF ALONG WITH THE HIGHER RESOLUTION
CAMS SUGGEST COVERAGE WILL BE LIMITED SO WE ONLY HAVE LOW POPS AT
THIS TIME. WE EXPECT HIGHS ABOVE NORMAL AGAIN TODAY...BUT DID
LOWER A BIT IN SPOTS DUE TO THE STRATUS IN PLACE EARLY. WE HAVE
HIGHS FROM AROUND 80 TO 85 FOR MOST AREAS.
THE FRONT WILL WEAKEN TUESDAY...BUT MAY STILL BE STRONG ENOUGH TO
FORCE A FEW SHOWERS/STORMS OVER PORTIONS OF NORTHWEST WISCONSIN
WHERE WE KEPT SOME POPS INTO THE AFTERNOON AND OVER FAR EASTERN
MINNESOTA IN THE MORNING. THERE MAY AGAIN BE SOME STRATUS/FOG THAT
FORM TONIGHT. HIGHS TUESDAY WILL AGAIN BE FROM 80 TO 85 FOR MOST
AREAS.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 240 AM CDT MON AUG 31 2015
WARM AND HUMID THROUGH THE REST OF THE WORK WEEK WITH OCCASIONAL
CHANCES FOR STORMS. THIS WEEKEND A STRONGER UPPER-LEVEL SYSTEM
COMBINED WITH A COLD FRONT MOVING IN FROM THE WEST WILL LEAD TO
BETTER CHANCES FOR WIDESPREAD SHOWERS AND STORMS OVER THE
WEEKEND...WITH MORE SEASONABLE TEMPERATURES BEHIND THE FRONT.
WED/THURS/FRI...FEELING LIKE MID-SUMMER WITH TEMPERATURES ABOVE
NORMAL...DEW POINTS IN THE MID 60S TO NEAR 70...AND CHANCES FOR
STORMS INCREASING TOWARDS THE WEEKEND. THIS PATTERN WILL BE DUE TO A
LONGWAVE TROUGH DEVELOPING IN THE WEST AND A WEAK RIDGE OVER THE
EASTERN THIRD OF THE COUNTRY...A PATTERN WHICH GENERALLY PERSISTS
MID TO LATE WEEK. WITH A WARM FRONT LIFTING NORTH WEDNESDAY WINDS
WILL BE BREEZY WEDNESDAY AND WINDY THURSDAY...GUSTS UP TO 30 MPH
POSSIBLE THURSDAY. WHILE THERE WILL BE A SLIGHT CHANCE FOR ISOLATED
STORMS WED AND THURS...THE BETTER CHANCES FOR STORMS COME FRIDAY
WHEN A MID-LEVEL SHORTWAVE TROUGH LIFTS THROUGH THE CENTRAL/NORTHERN
PLAINS INTO THE UPPER MIDWEST. PLENTY OF ELEVATED INSTABILITY AND
INCREASING UPPER LEVEL WINDS COULD SUSTAIN A FEW STRONG STORMS...BUT
IN GENERAL DO NOT EXPECT SEVERE THUNDERSTORMS. HIGHS IN THE LOW 80S.
SAT/SUN...A MUCH MORE ACTIVE PERIOD WITH A COLD FRONT EVENTUALLY
SWEEPING ACROSS THE UPPER MIDWEST...WITH MUCH COOLER TEMPERATURES
BEHIND THE FRONT ON TAP FOR NEXT WEEK. GFS IS A VERY WET OUTLIER
WITH FRONTAL PASSAGE QUICKER THAN OTHER GUIDANCE...WITH THE GEFS
ENSEMBLE MEMBERS DEPICTING A WIDE RANGE OF TIMING POSSIBILITIES.
THERE IS POTENTIAL FOR SOME STRONG TO SEVERE STORMS GIVEN STRONGER
WINDS ALOFT...BUT WILL CONTINUE TO HOLD OFF MENTIONING THIS
POSSIBILITY IN THE HWO DUE TO LOW CONFIDENCE WITH REGARDS TO IF THE
RIGHT CONDITIONS WILL DEVELOP. HIGH FREEZING LEVELS /12-14 KFT/ MAY
LIMIT POTENTIAL FOR LARGE HAIL...AND FAIRLY SATURATED MODEL
SOUNDINGS INDICATE MORE OF A HEAVY RAIN THREAT. GFS DEPICTS A SWATH
OF 2+ INCH RAINFALL OVER NORTHEAST MINNESOTA FOR SATURDAY AFTERNOON
WHICH SEEMS LIKE AN OUTLIER COMPARED TO THE GEFS ENSEMBLE MEAN OF 3-
4 TENTHS OF AN INCH. GEFS NARR-REFORECAST-CALIBRATED PRECIP
PROBABILITIES FROM ESRL/PSD...A METHOD OF TRYING TO CALIBRATE THE
GEFS FORECASTS TO PAST EVENTS TO PRODUCE A MORE RELIABLE FORECAST
THAN THE RAW GEFS PROBABILITIES...INDICATE ONLY A 10-20 PERCENT
CHANCE FOR 1"+ PRECIP OVER ANY 12-HOUR PERIOD THIS WEEKEND...SO
THERE IS LITTLE SUPPORT FOR THE DETERMINISTIC GFS FROM ITS ENSEMBLE
AND THEREFORE AM TREATING IT MORE AS AN INTERESTING OUTLIER THAN A
LIKELY SCENARIO. TEMPS WILL BE COOLER BEHIND THE FRONT...WHICH WILL
PROBABLY BE ON SUNDAY GIVEN THE ECMWF SLOWER TIMING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1220 PM CDT MON AUG 31 2015
VFR CONDITIONS WILL CONTINUE THROUGH TODAY WITH GUSTY S/SW WINDS
15 TO 25 KTS. A WEAK COLD FRONT WILL SLIDE ACROSS THE REGION THIS
EVENING AND MAINLY ACT TO INCREASE CLOUD COVER...BUT COULD ALSO
INTERACT WITH A WEAKLY UNSTABLE AIR MASS TO TRIGGER A FEW SHOWERS
AND STORMS. PRECIP/STORM PROBABILITIES ARE LOW...BUT NOT LOW
ENOUGH TO NOT MENTION IN THE TAF WITH A VCTS/SH. FRONT CLEARS THE
AREA LATE TONIGHT AND ALLOWS PATCHY FOG TO DEVELOP TUE MORNING.
COULD SEE IFR/MVFR VSBYS/CIGS AT TIMES...BUT NOTHING TOO
WIDESPREAD. VFR CONDITIONS RETURN BY MID MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 81 65 84 63 / 0 30 20 10
INL 85 54 82 56 / 10 30 10 30
BRD 83 63 85 66 / 0 20 10 10
HYR 81 66 84 63 / 0 20 20 10
ASX 83 65 82 61 / 0 20 20 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
UPDATE...GSF
SHORT TERM...MELDE
LONG TERM...JJM
AVIATION...TENTINGER
AREA FORECAST DISCUSSION
NWS DULUTH MN
1203 PM CDT MON AUG 31 2015
.UPDATE...
ISSUED AT 1203 PM CDT MON AUG 31 2015
THE FOG HAS DISSIPATED EXCEPT ALONG THE NORTH SHORE FROM TACONITE
HARBOR TO GRAND PORTAGE. THE STRATUS IS HANGING ON IN NW WI...BUT
SOME IMPROVEMENT IS OCCURRING. HAZY SUNSHINE ELSEWHERE DUE TO
SMOKE FROM WESTERN U.S. WILDFIRES. COLD FRONT IN NW MN HAS MADE
LITTLE PROGRESS EWD...ALTHOUGH SOME CLOUDS ARE MOVING TOWARD
KOOCHICHING COUNTY. HAVE ADJUSTED FOR THESE TRENDS.
UPDATE ISSUED AT 915 AM CDT MON AUG 31 2015
A COLD FRONT WAS DRAPED OVER EASTERN ND AND THE EXTREME CORNER OF NW
MN AT 14Z. THUNDERSTORMS WERE OCCURRING BEHIND THE FRONT IN NE ND
AND LIFTING NEWD INTO CANADA. SOUTHERLY FLOW OVER THE FORECAST
AREA HAS LED TO A STRATUS DECK OVER NW WI AND ADJACENT MN AND
ALONG THE NORTH SHORE OF LAKE SUPERIOR WITH SOME FOG THAT WAS
SLOWLY LIFTING. EXPECT THE STRATUS AND FOG TO CONTINUE TO ERODE
THIS MORNING AND HAVE ADJUSTED FOR THIS TREND. WITH THE STORMS
MOVING INTO CANADA AND LATEST HRRR INDICATING NO STORMS INTO THE
REGION THROUGH THE AFTERNOON FOR THE LAST FEW RUNS. HAVE REMOVED
THE MENTION OF STORMS TODAY.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 240 AM CDT MON AUG 31 2015
AN UPPER RIDGE WILL MOVE EAST OF THE REGION TODAY WITH SOUTHERLY
SURFACE FLOW KEEPING HIGHER DEWPOINTS IN PLACE. A COLD FRONT WILL
MOVE INTO FAR WESTERN MINNESOTA BY LATE AFTERNOON/EARLY EVENING
AND PROGRESS INTO NORTHEAST MINNESOTA TONIGHT BEFORE WEAKENING
TUESDAY.
STRATUS AND SOME PATCHY FOG HAVE ONCE AGAIN FORMED ACROSS
NORTHERN WISCONSIN AND PORTIONS OF NORTHEAST MINNESOTA THIS
MORNING. THE STRATUS/FOG SHOULD BURN OFF THIS MORNING AND THE RAP
SEEMS TO BE HANDLING THIS DECENTLY. CLOUDS WILL DIMINISH THROUGH
THE MORNING...THEN INCREASE AGAIN OVER WESTERN AREAS THIS
AFTERNOON AHEAD OF THE COLD FRONT. WE KEPT A MENTION OF
SHOWERS/STORMS IN THE WEST LATE TODAY...THEN PROGRESS THE CHANCE
EAST TONIGHT. THE NAM/GFS/ECMWF ALONG WITH THE HIGHER RESOLUTION
CAMS SUGGEST COVERAGE WILL BE LIMITED SO WE ONLY HAVE LOW POPS AT
THIS TIME. WE EXPECT HIGHS ABOVE NORMAL AGAIN TODAY...BUT DID
LOWER A BIT IN SPOTS DUE TO THE STRATUS IN PLACE EARLY. WE HAVE
HIGHS FROM AROUND 80 TO 85 FOR MOST AREAS.
THE FRONT WILL WEAKEN TUESDAY...BUT MAY STILL BE STRONG ENOUGH TO
FORCE A FEW SHOWERS/STORMS OVER PORTIONS OF NORTHWEST WISCONSIN
WHERE WE KEPT SOME POPS INTO THE AFTERNOON AND OVER FAR EASTERN
MINNESOTA IN THE MORNING. THERE MAY AGAIN BE SOME STRATUS/FOG THAT
FORM TONIGHT. HIGHS TUESDAY WILL AGAIN BE FROM 80 TO 85 FOR MOST
AREAS.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 240 AM CDT MON AUG 31 2015
WARM AND HUMID THROUGH THE REST OF THE WORK WEEK WITH OCCASIONAL
CHANCES FOR STORMS. THIS WEEKEND A STRONGER UPPER-LEVEL SYSTEM
COMBINED WITH A COLD FRONT MOVING IN FROM THE WEST WILL LEAD TO
BETTER CHANCES FOR WIDESPREAD SHOWERS AND STORMS OVER THE
WEEKEND...WITH MORE SEASONABLE TEMPERATURES BEHIND THE FRONT.
WED/THURS/FRI...FEELING LIKE MID-SUMMER WITH TEMPERATURES ABOVE
NORMAL...DEW POINTS IN THE MID 60S TO NEAR 70...AND CHANCES FOR
STORMS INCREASING TOWARDS THE WEEKEND. THIS PATTERN WILL BE DUE TO A
LONGWAVE TROUGH DEVELOPING IN THE WEST AND A WEAK RIDGE OVER THE
EASTERN THIRD OF THE COUNTRY...A PATTERN WHICH GENERALLY PERSISTS
MID TO LATE WEEK. WITH A WARM FRONT LIFTING NORTH WEDNESDAY WINDS
WILL BE BREEZY WEDNESDAY AND WINDY THURSDAY...GUSTS UP TO 30 MPH
POSSIBLE THURSDAY. WHILE THERE WILL BE A SLIGHT CHANCE FOR ISOLATED
STORMS WED AND THURS...THE BETTER CHANCES FOR STORMS COME FRIDAY
WHEN A MID-LEVEL SHORTWAVE TROUGH LIFTS THROUGH THE CENTRAL/NORTHERN
PLAINS INTO THE UPPER MIDWEST. PLENTY OF ELEVATED INSTABILITY AND
INCREASING UPPER LEVEL WINDS COULD SUSTAIN A FEW STRONG STORMS...BUT
IN GENERAL DO NOT EXPECT SEVERE THUNDERSTORMS. HIGHS IN THE LOW 80S.
SAT/SUN...A MUCH MORE ACTIVE PERIOD WITH A COLD FRONT EVENTUALLY
SWEEPING ACROSS THE UPPER MIDWEST...WITH MUCH COOLER TEMPERATURES
BEHIND THE FRONT ON TAP FOR NEXT WEEK. GFS IS A VERY WET OUTLIER
WITH FRONTAL PASSAGE QUICKER THAN OTHER GUIDANCE...WITH THE GEFS
ENSEMBLE MEMBERS DEPICTING A WIDE RANGE OF TIMING POSSIBILITIES.
THERE IS POTENTIAL FOR SOME STRONG TO SEVERE STORMS GIVEN STRONGER
WINDS ALOFT...BUT WILL CONTINUE TO HOLD OFF MENTIONING THIS
POSSIBILITY IN THE HWO DUE TO LOW CONFIDENCE WITH REGARDS TO IF THE
RIGHT CONDITIONS WILL DEVELOP. HIGH FREEZING LEVELS /12-14 KFT/ MAY
LIMIT POTENTIAL FOR LARGE HAIL...AND FAIRLY SATURATED MODEL
SOUNDINGS INDICATE MORE OF A HEAVY RAIN THREAT. GFS DEPICTS A SWATH
OF 2+ INCH RAINFALL OVER NORTHEAST MINNESOTA FOR SATURDAY AFTERNOON
WHICH SEEMS LIKE AN OUTLIER COMPARED TO THE GEFS ENSEMBLE MEAN OF 3-
4 TENTHS OF AN INCH. GEFS NARR-REFORECAST-CALIBRATED PRECIP
PROBABILITIES FROM ESRL/PSD...A METHOD OF TRYING TO CALIBRATE THE
GEFS FORECASTS TO PAST EVENTS TO PRODUCE A MORE RELIABLE FORECAST
THAN THE RAW GEFS PROBABILITIES...INDICATE ONLY A 10-20 PERCENT
CHANCE FOR 1"+ PRECIP OVER ANY 12-HOUR PERIOD THIS WEEKEND...SO
THERE IS LITTLE SUPPORT FOR THE DETERMINISTIC GFS FROM ITS ENSEMBLE
AND THEREFORE AM TREATING IT MORE AS AN INTERESTING OUTLIER THAN A
LIKELY SCENARIO. TEMPS WILL BE COOLER BEHIND THE FRONT...WHICH WILL
PROBABLY BE ON SUNDAY GIVEN THE ECMWF SLOWER TIMING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 653 AM CDT MON AUG 31 2015
ANOTHER MORNING WITH LIFR/IFR CEILINGS ACROSS THE
REGION...CONDITIONS WHICH SHOULD IMPROVE BY MID-MORNING. THIS
AFTERNOON WILL BE VFR WITH BREEZY WINDS OUT OF THE SOUTH...WINDS
STRONGEST AT BRD WHERE PEAK GUSTS TO AROUND 30 MPH ARE POSSIBLE.
THIS EVENING A WEAK FRONT WILL MOVE EAST ACROSS NORTHEAST
MINNESOTA WITH THE POTENTIAL FOR ISOLATED SHOWER/STORMS. CHANCES
ARE LOW...AND ONLY FELT CONFIDENT ENOUGH AT HIB TO INTRODUCE A
VCTS GROUP FOR THE EARLY EVENING. TONIGHT ANOTHER ROUND OF AT
LEAST MVFR VISIBILITY/CEILINGS ARE POSSIBLE AT DLH/HIB/HYR...BUT
THIS WILL BE DEPENDENT ON IF PRECIPITATION DEVELOPS AND HOW
WIDESPREAD IT BECOMES. INCLUDING A BEST GUESS IN THE TAFS ASSUMING
CONVECTION WILL BE ISOLATED IN NATURE AT BEST.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 81 65 84 63 / 0 30 20 10
INL 85 54 82 56 / 10 30 10 30
BRD 83 63 85 66 / 0 20 10 10
HYR 81 66 84 63 / 0 20 20 10
ASX 83 65 82 61 / 0 20 20 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
UPDATE...GSF
SHORT TERM...MELDE
LONG TERM...JJM
AVIATION...JJM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
300 PM EDT MON AUG 31 2015
.SYNOPSIS...AN UPPER LEVEL LOW WILL MOVE NORTHEASTWARD AWAY FROM THE
AREA THROUGH THE REST OF TODAY. OTHERWISE... A WEAK SURFACE TROUGH
WILL HOLD OVER EASTERN NORTH CAROLINA... WHILE HIGH PRESSURE
CENTERED OVER KENTUCKY EXTENDS OVER WESTERN NORTH CAROLINA.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM MONDAY...
THE SHIELD OF TROPICAL RAIN HAS SHIFTED EAST OF THE FORECAST AREA...
WHILE THE MID LEVEL LOW HAS MOVED WELL TO OUR NE. WHILE A FEW
SHALLOW SHOWERS REMAIN POSSIBLE... THE THREAT OF ADDITIONAL
SIGNIFICANT RAINFALL WILL HOLD JUST TO OUR EAST FOR THE REMAINDER OF
THE DAY. LATEST SURFACE ANALYSIS SHOWS LOW PRESSURE JUST OFF THE CHS
COAST... AND THIS WILL TRACK TO THE NNE ALONG THE SURFACE TROUGH
OVER ERN NC... ACCOMPANIED BY A MID LEVEL WAVE NOTED ON WATER VAPOR
IMAGERY JUST UPSHEAR. EXTRAPOLATION SUGGESTS THAT THE RAIN SHIELD IS
LIKELY TO HOLD JUST TO OUR EAST OR PERHAPS BRUSH ALONG THE FAR ERN
COASTAL PLAIN AS THE LOW TRACKS OVER ERN NC... A SCENARIO NEARLY IN
LINE WITH THE LATEST HRRR RUNS. WILL RETAIN A LOW CHANCE POP OVER
THE CENTRAL/ERN FORECAST AREA INTO EARLY EVENING... THEN EXPECT DRY
WEATHER OVERNIGHT AS THE DRIER AIR NOTED ON WATER VAPOR IMAGERY TO
OUR SW CONTINUES TO OVERSPREAD ALL OF CENTRAL NC. IT`S A DIFFERENT
STORY NEAR THE GROUND HOWEVER... AS HIGHER DEWPOINTS AND LOW LEVEL
MOISTURE HOLDING OVER THE ERN HALF OF NC ALONG WITH A WET GROUND AND
LIGHT OR CALM SURFACE WINDS LEAD TO FAVORABLE CONDITIONS FOR
FOG/STRATUS DEVELOPMENT... PARTICULARLY FROM THE TRIANGLE AND FAY TO
THE EAST/NORTHEAST. EXPECT ABOVE-NORMAL LOWS FROM 67-72. -GIH
&&
.SHORT TERM /TUESDAY AND TUESDAY NIGHT/...
AS OF 300 PM MONDAY...
A WEAK SURFACE PATTERN FEATURING A BROAD TROUGH OVER ERN NC AND KY-
CENTERED RIDGE EXTENDING INTO WRN NC WILL REMAIN IN PLACE... WHILE
ALOFT... HEIGHTS RISE OVER NC IN THE WAKE OF THE EXITING WAVE... AND
AHEAD OF THE LOW NOW OVER CENTRAL INDIANA. FORECAST SOUNDINGS DEPICT
FAIRLY DRY AND STABLE AIR THROUGH THE MID AND UPPER LEVELS...
ALTHOUGH A MODERATE AMOUNT OF LINGERING LOW LEVEL MOISTURE
ESPECIALLY IN THE EAST SHOULD RESULT IN SCATTERED TO BROKEN STRATOCU
PARTICULARLY FROM LATE MORNING THROUGH EARLY EVENING. ONCE THE
MORNING FOG LIFTS AND MIXES OVER THE NRN AND ERN CWA... EXPECT
GENERALLY PARTLY CLOUDY SKIES. WILL KEEP A SLIGHT CHANCE OF AN
AFTERNOON SHOWER OR STORM IN THE FAR ERN CWA... WHERE LOW LEVEL
MOISTURE WILL BE BETTER AND WHERE MUCAPE IS FORECAST TO APPROACH OR
EXCEED 1000 J/KG... BUT THE LACK OF A FOCUS FOR ASCENT AND LIMITED
MOISTURE ALOFT SHOULD KEEP COVERAGE LOW. HIGHS 88-92 WITH
THICKNESSES A BIT ABOVE NORMAL. FAIR TO PARTLY CLOUDY TUE NIGHT WITH
LOWS 69-72. -GIH
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 300 PM MONDAY...
A FAIRLY LOW CONFIDENCE FORECAST FOR THE EXTENT OF THE LONG TERM AS
THERE IS VERY LITTLE FORCING IN THE UPPER LEVELS WITH NO REAL
DISCERNIBLE JETS OR STRONG SHORTWAVES IN THE VICINITY OF CENTRAL NC.
THEREFORE MUCH OF THE LONG TERM FORECAST WILL BE BUILT AROUND LOWER
LEVEL FEATURES.
WEDNESDAY SHOULD BE FAIRLY UNEVENTFUL WITH VERY WEAK HIGH PRESSURE
OVER THE WESTERN ATLANTIC AND A SURFACE LOW MOVING THROUGH EASTERN
CANADA. THE SURFACE FRONT ASSOCIATED WITH THIS FEATURE WILL BE VERY
WEAK WITH NOT MUCH OF AN AIRMASS CHANCE BUT MAYBE JUST ENOUGH
FORCING FOR A SLIGHT UPTICK IN CONVECTION ON THURSDAY
AFTERNOON/EVENING WITH SHOWERS LINGERING INTO THE EARLY MORNING
HOURS ON FRIDAY.
DURING THE DAY ON FRIDAY HIGH PRESSURE WILL BEGIN TO STRENGTHEN OVER
NEW ENGLAND AND RETROGRADE SOUTHWESTWARD INTO THE MID ATLANTIC
STATES. THIS WILL HELP PUSH A BACK DOOR COLD FRONT THROUGH THE AREA
LATER ON FRIDAY AND GIVING US A COOLER AIRMASS FOR THE WEEKEND AND
INTO MONDAY.
TEMPERATURES WILL MAINLY RUN IN THE UPPER 80S/LOW 90S EARLY IN THE
PERIOD AND THEN DROP INTO THE LOW TO MID 80S FOR THE WEEKEND AND
INTO EARLY NEXT WEEK. LOWS GENERALLY IN THE MID TO UPPER 60S. PRECIP
CHANCES WILL MAINLY BE SLIGHT CHANCE THROUGH THE WORK WEEK WITH
CHANCE POPS FOR THE WEEKEND. -RE
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 125 PM MONDAY...
MVFR CONDITIONS ARE LIKELY TO DOMINATE AT INT/GSO/FAY INTO
TONIGHT... WHILE IFR/LIFR CONDITIONS ARE EXPECTED TO DOMINATE AT
RDU/RWI. A STREAM OF TROPICAL MOISTURE WHICH BROUGHT THIS MORNING`S
RAIN IS BEING PUSHED SLOWLY EASTWARD INTO COASTAL NC... BUT LOWER
CIGS REMAIN WELL BACK INTO CENTRAL NC WITH WEAK SURFACE WINDS AND
PLENTY OF LINGERING LOW LEVEL MOISTURE. THESE TWO FACTORS WILL KEEP
A HIGH CHANCE OF SUB-VFR CIGS THROUGH THIS EVENING AT CENTRAL NC
TERMINALS... ALTHOUGH INT/GSO/FAY MAY BRIEFLY BREAK OUT TO VFR THIS
AFTERNOON. CIGS SHOULD REMAIN IFR AT RDU/RWI... ALTHOUGH THESE SITES
TOO MAY BRIEFLY JUMP UP A CATEGORY TO MVFR TODAY. CLOUDS ARE
EXPECTED TO BECOME SCT AT INT/GSO OVERNIGHT... BUT WITH A THREAT OF
MVFR TO IFR VSBYS IN FOG. AT FAY AND ESPECIALLY AT RDU/RWI... CIGS
ARE EXPECTED TO HOLD AT IFR OR EVEN LIFR OVERNIGHT INTO TUE
MORNING... WITH A RISK OF MVFR TO IFR FOG. LOW CLOUDS SHOULD SLOWLY
LIFT AND MIX OUT TO MVFR THEN VFR TUE MORNING IN THE 14-18Z TIME
FRAME... WITH CIGS AT RWI LAST TO LIFT TO VFR.
LOOKING BEYOND 18Z TUE: VFR CONDITIONS ARE EXPECTED TUE AFTERNOON
INTO TUE NIGHT... BUT MVFR TO IFR FOG IS POSSIBLE LATE TUE NIGHT
INTO WED MORNING. VFR CONDITIONS SHOULD THEN PREVAIL THROUGH SAT.
SCATTERED SUB-VFR SHOWERS/STORMS ARE POSSIBLE EACH AFTERNOON/EVENING
WED THROUGH SAT... ALTHOUGH FORECAST CONFIDENCE IS QUITE LOW WITH
DETAILS OF POSSIBLE TIMING OR COVERAGE. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...KS
NEAR TERM...HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...ELLIS
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
125 PM EDT MON AUG 31 2015
.SYNOPSIS...AN UPPER LEVEL LOW WILL MOVE NORTHEASTWARD AWAY FROM THE
AREA THROUGH THE REST OF TODAY. OTHERWISE... A WEAK SURFACE TROUGH
WILL HOLD OVER EASTERN NORTH CAROLINA... WHILE HIGH PRESSURE
CENTERED OVER KENTUCKY EXTENDS OVER WESTERN NORTH CAROLINA.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 935 AM MONDAY...
EARLIER UPDATE TARGETED THE CENTRAL/ERN CWA WITH HIGHEST POPS
(LIKELY TO CATEGORICAL) FOR THE ONGOING TROPICAL RAINFALL. THESE HIGH
POPS WILL SHIFT SLOWLY EASTWARD OVER THE NEXT SEVERAL HOURS AS THE
UPPER LEVEL LOW THAT CROSSED THE STATE EARLIER THIS MORNING HEADS
NNE INTO VA. RAIN RATES OF 1-2 INCHES PER HOUR HAVE BEEN COMMON...
ENOUGH TO PRODUCE SOME MINOR URBAN AND STREET FLOODING AND RISING
CREEKS BUT UNDER FLOODING THRESHOLDS... AND THIS RAIN SHOULD
ACTUALLY BE BENEFICIAL FOR MOST. WATER VAPOR IMAGERY SHOWS DRYING
OVER THE WRN CWA... SO WHILE A FEW WRAPAROUND SHOWERS ARE POSSIBLE
IN AREAS NW OF THE TRIANGLE... THESE SHOULD GENERATE LITTLE
ADDITIONAL RAINFALL. EASTERN SECTIONS ESPECIALLY ALONG AND EAST OF I-
95 MAY SEE A SLOWER TAPERING OF THE WIDESPREAD MODERATE RAIN...
GIVEN THAT ANOTHER WAVE NOW APPROACHING SAVANNAH GA WILL BE TRACKING
TO THE N OR NNE... SLOWING THE ARRIVAL OF DRIER AIR... AND THIS
TREND IS NOTED WELL IN THE RECENT RAP RUNS. POPS WILL START OUT
RANGING FROM ISOLATED AT MOST WEST TO CATEGORICAL EAST... TRENDING
DOWNWARD WEST TO EAST THROUGH THE REST OF THE DAY. ANY INSTABILITY
SHOULD BE MARGINAL... WITH MUCAPE MOSTLY HOLDING AT OR BELOW 1000
J/KG... SO WILL KEEP ANY THUNDER MENTION AT ISOLATED TO SCATTERED AT
MOST. TEMPS ARE A TOUGH CALL GIVEN THE GREATLY LIMITED INSOLATION IN
THE EAST... SO EXPECT HIGHS IN THE LOW-MID 80S WEST AND NEAR 80 TO
LOWER 80S EAST... WITH THESE EASTERN HIGHS NOT BEING REACHED UNTIL
VERY LATE IN THE DAY. -GIH
LOWS TONIGHT IN THE UPPER 60S TO LOWER 70S.
&&
.SHORT TERM /TUESDAY AND TUESDAY NIGHT/...
AS OF 345 AM MONDAY...
A WEAK/NONDESCRIPT SFC PATTERN WILL EXTEND ACROSS THE AREA ON
TUESDAY WITH HEIGHTS ALOFT BUILDING OVER THE SOUTHEAST AS THE
SUBTROPICAL RIDGE OVER THE SOUTHWEST ATLANTIC RETROGRADES WESTWARD.
OTHER THAN DAYTIME HEATING ATOP A SEASONABLY MOIST AIRMASS...
FORCING MECHANISM IS LACKING WITH ISOLATED DIURNAL CONVECTION AT
BEST.
HIGHS IN THE UPPER 80S TO LOWER 90S. LOWS IN THE UPPER 60S TO LOWER
70S.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 310 AM MONDAY...
MEDIUM RANGE MODELS ARE IN GENERAL AGREEMENT IN SHOWING A WEAK
DISTURBANCE ALOFT TRACKING FROM THE OHIO VALLEY MIDWEEK TO ACROSS
CENTRAL NC THURSDAY OR THURSDAY NIGHT. HOWEVER... THE LATEST GFS AND
ECMWF CONTINUE TO DISAGREE WRT WHAT HAPPENS TO IT. THE LATEST ECMWF
CONTINUES TO SHOW THE S/W SHIFTING TO THE EAST/SOUTHEAST AND
OFFSHORE BY THURSDAY AFTERNOON... WITH BRIEF S/W RIDGING BUILDING
OVER THE AREA BEFORE A WEAK MID LEVEL LOW LIFTS NORTHEASTWARD OUT OF
THE NORTHWEST GULF OF MEXICO AND INTO THE CAROLINAS BY FRIDAY NIGHT
AND LINGERING THROUGH THE END OF THE FORECAST PERIOD. MEANWHILE...
THE LATEST GFS IS SLOWER MOVING THE INITIAL S/W DISTURBANCE THROUGH
THE AREA ON THURSDAY... LINGERING INTO FRIDAY MORNING. THE S/W IS
THEN EXPECTED TO CLOSE OFF INTO A MID LEVEL LOW AND CONTINUE TO
SLOWLY SINK SOUTHWARD AS A STRONG 595 DECAMETER HIGH BEGINS TO BUILD
SOUTHWARD TOWARDS CENTRAL NC. GIVEN THIS PATTERN... THE LOW IN THE
NORTHWESTERN GULF OF MEXICO ACTUALLY SINKS FURTHER SOUTH AND NOT IN
THE DIRECTION OF CENTRAL. AT THE SURFACE... WE SHOULD SEE SOME TYPE
OF WEAK SURFACE TROUGH TRACK ACROSS THE AREA WITH THE INITIAL S/W
DISTURBANCE... WITH SURFACE HIGH PRESSURE BUILDING/EXTENDING INTO
CENTRAL NC FROM THE NORTH/NORTHEAST DURING THE WEEKEND. THUS... AT
THIS TIME... WILL KEEP POPS GENERALLY LOW... SLIGHT CHANCE TO LOW
END CHANCE DURING THE MEDIUM RANGE... GIVEN THE UNCERTAINTY IN WHAT
WILL GENERALLY BE MEAN RIDING OVER THE EASTERN HALF OF THE COUNTRY
DURING THIS TIME (WITH THE EMBEDDED DISTURBANCES/WEAK CLOSED LOWS).
HIGH TEMPS WILL GENERALLY BE NEAR TO SLIGHTLY ABOVE NORMAL FOR THE
MID TO LATE WEEK TIME FRAME... THEN NEAR NORMAL TO POSSIBLY SLIGHT
BELOW NORMAL FOR THE WEEKEND. LOW TEMPS ARE EXPECTED TO BE NEAR TO
SLIGHTLY ABOVE NORMAL DURING THE PERIOD.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 125 PM MONDAY...
MVFR CONDITIONS ARE LIKELY TO DOMINATE AT INT/GSO/FAY INTO
TONIGHT... WHILE IFR/LIFR CONDITIONS ARE EXPECTED TO DOMINATE AT
RDU/RWI. A STREAM OF TROPICAL MOISTURE WHICH BROUGHT THIS MORNING`S
RAIN IS BEING PUSHED SLOWLY EASTWARD INTO COASTAL NC... BUT LOWER
CIGS REMAIN WELL BACK INTO CENTRAL NC WITH WEAK SURFACE WINDS AND
PLENTY OF LINGERING LOW LEVEL MOISTURE. THESE TWO FACTORS WILL KEEP
A HIGH CHANCE OF SUB-VFR CIGS THROUGH THIS EVENING AT CENTRAL NC
TERMINALS... ALTHOUGH INT/GSO/FAY MAY BRIEFLY BREAK OUT TO VFR THIS
AFTERNOON. CIGS SHOULD REMAIN IFR AT RDU/RWI... ALTHOUGH THESE SITES
TOO MAY BRIEFLY JUMP UP A CATEGORY TO MVFR TODAY. CLOUDS ARE
EXPECTED TO BECOME SCT AT INT/GSO OVERNIGHT... BUT WITH A THREAT OF
MVFR TO IFR VSBYS IN FOG. AT FAY AND ESPECIALLY AT RDU/RWI... CIGS
ARE EXPECTED TO HOLD AT IFR OR EVEN LIFR OVERNIGHT INTO TUE
MORNING... WITH A RISK OF MVFR TO IFR FOG. LOW CLOUDS SHOULD SLOWLY
LIFT AND MIX OUT TO MVFR THEN VFR TUE MORNING IN THE 14-18Z TIME
FRAME... WITH CIGS AT RWI LAST TO LIFT TO VFR.
LOOKING BEYOND 18Z TUE: VFR CONDITIONS ARE EXPECTED TUE AFTERNOON
INTO TUE NIGHT... BUT MVFR TO IFR FOG IS POSSIBLE LATE TUE NIGHT
INTO WED MORNING. VFR CONDITIONS SHOULD THEN PREVAIL THROUGH SAT.
SCATTERED SUB-VFR SHOWERS/STORMS ARE POSSIBLE EACH AFTERNOON/EVENING
WED THROUGH SAT... ALTHOUGH FORECAST CONFIDENCE IS QUITE LOW WITH
DETAILS OF POSSIBLE TIMING OR COVERAGE. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...KS
NEAR TERM...HARTFIELD/CBL
SHORT TERM...CBL
LONG TERM...77
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1237 PM CDT MON AUG 31 2015
.UPDATE...
ISSUED AT 1233 PM CDT MON AUG 31 2015
DROPPED ALL CHANCES FOR PRECIPITATION FOR THE REMAINDER OF TODAY.
ADDED HIGH CLOUDS TO THE SOUTH CENTRAL WHERE SKIES SHOULD BE
PARTLY SUNNY. SUNNY WEST AND NORTH.
UPDATE ISSUED AT 956 AM CDT MON AUG 31 2015
AT 9 PM CDT...A COLD FRONT WAS PROCEEDING THROUGH THE EASTERN
PORTION OF THE STATE. SKIES WERE CLEARING ACROSS THE WEST. BREEZY
CONDITIONS WILL SOON DEVELOP WEST. TRIMMED THE POPS BACK TO FOLLOW
THE FRONTAL BOUNDARY EAST. THE CHANCES FOR PRECIP WILL END BY
NOON. TEMPERATURES LOOK GOOD.
UPDATE ISSUED AT 632 AM CDT MON AUG 31 2015
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS CONTINUE TO LIFT
NORTHEAST ACROSS NORTHERN AND EASTERN NORTH DAKOTA. CONVECTION HAS
EXITED THE SOUTHWEST QUARTER OF THE STATE. MAIN UPDATE WAS TO POPS
BASED ON LATEST RADAR AND THE TIME LAGGED HRRR OUTPUT THROUGH THIS
MORNING. OTHERWISE NO SIGNIFICANT UPDATES NEEDED.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 335 AM CDT MON AUG 31 2015
SHOWERS AND THUNDERSTORMS ENDING BY NOON. THEN BREEZY WEST WINDS
BRING A DRIER AND COOLER AIRMASS INTO THE STATE.
A SURFACE COLD FRONT EXTENDED FROM AROUND LAKE WINNIPEG
SOUTHWESTWARD TO THE TURTLE MOUNTAIN AND DEVILS LAKE AREA...TO NEAR
BISMARCK TO THE BLACK HILLS AREA IN WESTERN SOUTH DAKOTA. SCATTERED
SHOWERS AND THUNDERSTORMS CONTINUED TO DEVELOP ALONG AND WEST OF THE
SURFACE FRONT...MOVING NORTHEASTWARD ALONG THE UPPER LEVEL FLOW. AT
UPPER LEVELS...A SERIES OF UPPER LEVEL IMPULSES WERE MOVING
NORTHEASTWARD FROM WYOMING INTO THE CENTRAL AND WESTERN DAKOTAS. A
STRONG UPPER LEVEL SHORTWAVE WAS FARTHER WEST OVER CENTRAL
MONTANA/SOUTHERN SASKATCHEWAN...AND IS FORECAST TO CONTINUE LIFTING
NORTHEASTWARD ACROSS NORTHWESTERN NORTH DAKOTA AND INTO SOUTHERN
MANITOBA.
THE SURFACE COLD FRONT IS FORECAST TO MOVE EAST...REACHING THE RED
RIVER VALLEY AREA AROUND NOON. THE SHOWERS AND THUNDERSTORMS SHOULD
BE ENDING IN THE SOUTHWEST EARLY THIS MORNING...AND ENDING BY EARLY
AFTERNOON IN THE FAR NORTH AND JAMES RIVER VALLEY. THIS SHOULD OCCUR
AS THE LAST OF THE UPPER LEVEL IMPULSES AND STRONG SHORTWAVE MOVE
EAST OUT OF WESTERN AND CENTRAL NORTH DAKOTA.
A SECONDARY SURGE OF COOLER AND DRIER AIR WELL BEHIND THE FRONT
IS PROGGED TO PUSH INTO FAR WESTERN NORTH DAKOTA BEFORE DAYBREAK
THIS MORNING...WITH H850 WINDS OF 25 TO 35 KNOTS AT THE LEADING EDGE
OF THE AIRMASS. THIS IS DRY AIR MOVING ACROSS THE ROCKIES AND INTO
THE FRONT RANGE. CURRENT DEWPOINT TEMPERATURES IN THE WEST WERE IN
THE 50S WITH 60S IN THE EASTERN HALF OF THE STATE. THIS AFTERNOON
THE DEWPOINTS SHOULD BE AS LOW AS THE LOW TO MID 30S IN WESTERN
NORTH DAKOTA...AND IN THE 40S AND 50S EAST. HIGHS IN THE UPPER 70S
WEST WILL RESULT IN AFTERNOON MINIMUM RELATIVE HUMIDITY VALUES
AROUND 20 PERCENT. WEST WINDS OF 20 TO 25 MPH WITH GUSTS TO 30 MPH
CAN BE EXPECTED LATER THIS MORNING...BUT SHOULD DIMINISH SOMEWHAT
THIS AFTERNOON AFTER THE INITIAL PUSH OF DRY AIR. THUS THE STRONGEST
WINDS TODAY SHOULD NOT COINCIDE WITH THE LOWEST RELATIVE HUMIDITY
VALUES...AND RED FLAG CRITERIA ARE NOT EXPECTED TO BE MET.
LOOK FOR BREEZY WEST WINDS TO DEVELOP TODAY WITH DECREASING CLOUDS
FROM SOUTHWEST TO NORTHEAST. HIGHS SHOULD RANGE FROM THE UPPER 70S
NORTH AND WEST TO THE LOW TO MID 80S SOUTH CENTRAL.
DECREASING WINDS THIS EVENING WITH CLEAR SKIES. LOWS SHOULD BE
MAINLY IN THE 50S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 335 AM CDT MON AUG 31 2015
CONTINUED WARM TEMPERATURES AND SLIGHT/PERIODIC THUNDERSTORM CHANCES
WILL HIGHLIGHT THE EXTENDED FORECAST PERIOD THROUGH THE WORK WEEK.
MODEL DIFFERENCES APPEAR BY THE WEEKEND WITH A POSSIBLE PATTERN
CHANGE INTO THE EARLY PORTIONS OF NEXT WEEK.
ON TUESDAY...MAINTAINED A SLIGHT CHANCE OF MAINLY EVENING AND
OVERNIGHT THUNDERSTORMS FOR THE DEVILS LAKE BASIN AND JAMES RIVER
VALLEY WITH MODELS STILL SHOWING INCREASING INSTABILITY WITH DAYTIME
HEATING COUPLED WITH AN INCREASING LOW LEVEL JET ACROSS THE EASTERN
HALF OF THE STATE. CAPPING DURING THE DAY MAY HOLD OFF ON CONVECTION
UNTIL AFTER 00Z.
BEYOND TUESDAY...OUR SOUTHWEST UPPER FLOW WILL CONTINUE THROUGH THE
END OF THE WORK WEEK WITH TROUGHING ACROSS THE PACIFIC NORTHWEST AND
RIDGING OFF TO OUR EAST. A QUASI-STATIONARY SURFACE TROUGH COMBINED
WITH ANY EMBEDDED WAVES ALOFT WILL PROVIDE A FOCUS FOR MAINLY
ISOLATED DAILY SHOWER AND THUNDERSTORM ACTIVITY. BEST CHANCES APPEAR
TO BE TOWARDS THE END OF THE WORK WEEK AND INTO NEXT WEEKEND WHEN A
STRONG UPPER JET APPROACHES THE NORTHERN PLAINS. TEMPERATURES WILL
REMAIN NEAR TO SLIGHTLY ABOVE NORMAL THROUGH THE WORK WEEK.
DISAGREEMENT IN DETERMINISTIC MODELS CROPS UP BY THE WEEKEND
REGARDING THE STRONG UPPER LEVEL TROUGH TO OUR WEST. THE 00 UTC 31
AUG GFS IS NOW MUCH MORE PROGRESSIVE AND WEAKER WITH THIS FEATURE.
THUS COOLER CONDITIONS ENTER THE NORTHERN PLAINS SATURDAY AND SUNDAY
WITH A WARM-UP RETURNING BY THE BEGINNING OF NEXT WEEK. THE ECMWF
IS MUCH SLOWER AND STRONGER...KEEPING IT MILD THROUGH THE FIRST
HALF OF THE WEEKEND...THEN COOLING SUNDAY INTO EARLY NEXT WEEK AND
WITH MUCH COLDER TEMPERATURES OVER THE AREA EARLY NEXT WEEK. THE
GLOBAL GEM WAS ALSO SHOWING A SLOWER SOLUTION THAN THE GFS THROUGH
SUNDAY. THE GFSENSEMBLE SPREAD WAS MUCH GREATER LATE IN THE
WEEKEND COMPARED TO THE ECMWF ENSEMBLE...THUS MAYBE AN INDICATION
THAT THE SLOWER SOLUTION WILL PREVAIL. BUT FOR NOW WILL HOLD
STEADY WITH OUR CURRENT MODEL BLEND SOLUTION WHICH IS STILL
TRENDING COOLER FOR THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1233 PM CDT MON AUG 31 2015
AT NOON CDT A COLD FRONT WAS PROGRESSING THROUGH EASTERN NORTH
DAKOTA WITH HIGH PRESSURE BUILDING INTO MONTANA. VFR EXPECTED
THROUGH TEH 18ZTAF PERIOD,.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...JV
LONG TERM...TWH
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS NORMAN OK
326 PM CDT MON AUG 31 2015
.DISCUSSION...
A WEAK UPPER LOW CONTINUES TO SPIN ACROSS SOUTHEAST OKLAHOMA.
ALTHOUGH LATEST RAP & HRRR RUNS KEEP IT INACTIVE THERE, WATER
VAPOR IMAGERY CONTINUES TO SHOW A SLIGHT MIDLEVEL CIRCULATION,
ENOUGH TO MAINTAIN LOW TSRA POPS THERE UNTIL THIS EVENING.
OTHERWISE, AN UPPER RIDGE IS EXPECTED TO BUILD THROUGH MUCH OF THE
WEEK, KEEPING US DRY AND MAINTAINING SEASONABLY NORMAL
TEMPERATURES. HOWEVER, THE ECMWF SOLUTION SUGGEST A SHORT WAVE
DISTURBANCE DIGGING ACROSS FAR NORTHWEST OKLAHOMA FOR THURSDAY
NIGHT. FOR NOW, WILL BE KEEPING ANY POPS OUT OF THERE, MAINLY DUE
TO UNCERTAINTY OF MOISTURE AVAILABILITY.
A MUCH DEEPER TROUGH WILL BE DIGGING ACROSS THE NORTHERN U.S.
DURING THE WEEKEND, WHICH WILL BE PUSHING A COLD FRONT INTO OUR
AREA BEGINNING FOR MONDAY. AT THIS POINT, BOTH LONG RANGE MODELS
HINT A PACIFIC BASED MIDLEVEL MOISTURE PLUME, ORIGINATING FROM THE
GULF OF CALIFORNIA, EXTENDING INTO NORTHWEST OKLAHOMA BEGINNING
SUNDAY. WITH THE COLD FRONT APPROACHING NEAR THE TIME PERIOD, IT
WOULD CERTAINLY NOT RULE OUT LOW TSRA POPS IN OUR NORTHWEST FOR
THE SUNDAY THROUGH MONDAY TIME FRAME.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 71 92 70 92 / 0 0 0 0
HOBART OK 70 95 71 95 / 0 0 0 0
WICHITA FALLS TX 72 95 71 95 / 0 0 0 0
GAGE OK 69 94 70 94 / 0 0 10 0
PONCA CITY OK 71 93 70 92 / 0 0 0 0
DURANT OK 71 94 71 94 / 10 10 10 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
17/67
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
613 PM EDT MON AUG 31 2015
.SYNOPSIS...
A MODERATELY HIGH AMOUNT OF MOISTURE STREAMING EAST FROM THE OHIO
VALLEY WILL EXTEND ACROSS PENN THROUGH MUCH OF THIS WEEK. THE
CLOSE PROXIMITY OF A NEARLY EAST- WEST FRONTAL BOUNDARY ACROSS
PENNSYLVANIA WILL LEAD TO ISOLATED SHOWERS TODAY THROUGH THURSDAY.
HIGH PRESSURE OFF THE EAST COAST WILL RIDGE NORTHWEST INTO
PENNSYLVANIA AND LEAD TO TEMPERATURES WELL ABOVE NORMAL THIS
ENTIRE WEEK. IT WILL FEEL MORE LIKE THE MIDDLE OF SUMMER THAN
SEPTEMBER.
&&
.NEAR TERM /UNTIL 11 PM THIS EVENING/...
EVENING CONVECTION DWINDLING RAPIDLY AS MERE REMNANTS OF WHAT
EARLIER WERE LOCALLY HEAVY DOWNPOURS LINGER OVER SOUTHERN
PORTIONS OF THE LAUREL HIGHLANDS AND ARE JUST EXITING SOUTHERN
SCHUYLKILL COUNTY AS WELL. NOT EXPECTING ANY ADDITIONAL
DEVELOPMENT THIS EVENING...AS PER LATEST HRRR WHICH HAD A GOOD
HANDLE ON THE EXPLICIT DISSIPATION OF DIURNAL ACTIVITY THIS
EVENING. DROPPED LATE EVENING POPS AS A RESULT.
&&
.SHORT TERM /11 PM THIS EVENING THROUGH 6 PM TUESDAY/...
FOG IS NOT A SLAM-DUNK TONIGHT...BUT HIGH MOISTURE AND CLEARING
SKY SHOULD ALLOW FOR THE VALLEYS TO FOG UP AS IS USUAL IN SEPT.
YES...SEPT ALREADY. WILL ALSO MENTION SOME PATCHY FOG IN THE SRN
TIER WHERE IT IS RAINING. MINS SHOULD RUN IN THE MUGGY 60S AND
L70S AGAIN. TUESDAY LOOKS LIKE IT SHOULD HOLD FEWER SHOWERS...WITH
LITTLE FORCING AND ONLY WEAK BOUNDARIES RUNNING ABOUT.
THUS...WILL KEEP POPS TO 20S IN THE SW.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
ANOMALOUS UPPER LEVEL RIDGE IS FORECAST TO DOMINATE THE EASTERN
THIRD TO HALF OF THE UNITED STATES TROUGH THE LONG TERM PERIOD.
THIS WILL LEAD TO ABOVE- NORMAL TEMPERATURES FOR MUCH OF THE
PERIOD. THE WARMTH AND INCREASING HUMIDITY SHOULD ALLOW FOR AT
LEAST A SLIGHT CHC OF DIURNAL CONVECTION EACH DAY...BUT WARM MID-
LEVELS WILL KEEP THE PROBABILITY OF WIDESPREAD RAINFALL QUITE LOW.
THE HIEST CHANCES FOR PRECIP WILL BE DURING THE MID-LATE WEEK
PERIOD /WED-THU-FRI/ WITH A COUPLE SUBTLE FEATURES. FIRST...A WEAK
UPPER LEVEL WAVE /BEST PROGGED ON THE ECMWF/ SLIPS OVERHEAD ON WED
AS THE BERMUDA HIGH BRIEFLY RECEDES. AT SAME TIME A WEAK BACKDOOR
COLD FRONT SLIPS SOUTHWARD OFF THE EAST COAST. THIS COULD HELP
POOL SOME LOW LEVEL MOISTURE OVER THE MID ATLANTIC AND OHIO VALLEY
AS MID LEVELS COOL JUST A BIT...BRINGING POTENTIAL FOR SCT TSTMS.
RIDGE BUILDS BACK IN FOR FRI...BUT ANOTHER SURFACE BACKDOOR FRONT
TRIES TO SLIP ACROSS THE STATE AS SURFACE HIGH EXPANDS IN FROM THE
NORTH. THIS BOUNDARY SHOULD BRING SCT CONVECTION FOR FRI.
EXTENDED MODELS HINT AT POTENTIAL FOR DAILY CONVECTION CONTINUING
INTO THE WEEKEND ALONG SOUTHER BORDER...BUT OVERALL CONDITIONS
WILL BE MAINLY RAIN-FREE.
TEMPS PEAK MIDWEEK WITH READINGS APPROACHING 90F IN THE SE...AND
EVEN GETTING INTO THE 80S ELSE HERE...EASILY WELL ABOVE NORMAL
FOR THE FIRST WEEK OF SEPT. LOWS WILL ALSO REMAIN QUITE MILD
MID/LATE WEEK AS HIGH HUMIDITY AIR HANGS AROUND. SLIGHTLY COOLER
BUT STILL ABOVE AVERAGE TEMPS WILL CONTINUE THROUGH THE WEEKEND.
&&
.AVIATION /22Z MONDAY THROUGH SATURDAY/...
ISOLATED SHOWERS ACROSS SOUTHERN PA SHOULD DISSIPATE AROUND SUNSET
AS THE ATMOSPHERE COOLS/STABILIZES. MAIN FOCUS TONIGHT WILL BE ON
LATE NIGHT FOG...WHICH APPEARS A NEAR CERTAINTY IN THE DEEP VALLEYS
OF NORTH CENTRAL PA. LATEST MDL OUTPUT...COMBINED WITH CONDITIONAL
CLIMATOLOGY...IMPLY AT LEAST A 50 PCT CHC OF A PERIOD OF IFR
CONDS AT KBFD/KIPT/KAOO LATE TONIGHT...ONLY A SLIGHT CHC AT
KUNV/KLNS AND NEARLY NO CHC OF SIG REDUCTIONS AT KJST/KMDT.
ANY AM FOG SHOULD BURN OFF BY BTWN 12Z-14Z. OTHERWISE...HIGH
PRESSURE OFF THE EAST COAST WILL ENSURE WIDESPREAD VFR CONDS AND
LIGHT WINDS ON TUESDAY. THERE IS JUST A SLIGHT CHC OF A PM
SHRA/TSRA IN VICINITY OF KJST.
OUTLOOK...
WED-SAT...PATCHY AM FOG POSS...MAINLY KIPT/KBFD. ISOLD PM TSRA
IMPACTS POSSIBLE...MAINLY W.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO/DEVOIR
SHORT TERM...DANGELO
LONG TERM...LAMBERT
AVIATION...DANGELO/FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
550 PM EDT MON AUG 31 2015
.SYNOPSIS...
A MODERATELY HIGH AMOUNT OF MOISTURE STREAMING EAST FROM THE OHIO
VALLEY WILL EXTEND ACROSS PENN THROUGH MUCH OF THIS WEEK. THE
CLOSE PROXIMITY OF A NEARLY EAST- WEST FRONTAL BOUNDARY ACROSS
PENNSYLVANIA WILL LEAD TO ISOLATED SHOWERS TODAY THROUGH THURSDAY.
HIGH PRESSURE OFF THE EAST COAST WILL RIDGE NORTHWEST INTO
PENNSYLVANIA AND LEAD TO TEMPERATURES WELL ABOVE NORMAL THIS
ENTIRE WEEK. IT WILL FEEL MORE LIKE THE MIDDLE OF SUMMER THAN
SEPTEMBER.
&&
.NEAR TERM /UNTIL 11 PM THIS EVENING/...
EVENING CONVECTION DWINDLING RAPIDLY AS MERE REMNANTS OF WHAT
EARLIER WERE LOCALLY HEAVY DOWNPOURS LINGER OVER SOUTHERN
PORTIONS OF THE LAUREL HIGHLANDS AND ARE JUST EXITING SOUTHERN
SCHUYLKILL COUNTY AS WELL. NOT EXPECTING ANY ADDITIONAL
DEVELOPMENT THIS EVENING...AS PER LATEST HRRR WHICH HAD A GOOD
HANDLE ON THE EXPLICIT DISSIPATION OF DIURNAL ACTIVITY THIS
EVENING. DROPPED LATE EVENING POPS AS A RESULT.
&&
.SHORT TERM /11 PM THIS EVENING THROUGH 6 PM TUESDAY/...
FOG IS NOT A SLAM-DUNK TONIGHT...BUT HIGH MOISTURE AND CLEARING
SKY SHOULD ALLOW FOR THE VALLEYS TO FOG UP AS IS USUAL IN SEPT.
YES...SEPT ALREADY. WILL ALSO MENTION SOME PATCHY FOG IN THE SRN
TIER WHERE IT IS RAINING. MINS SHOULD RUN IN THE MUGGY 60S AND
L70S AGAIN. TUESDAY LOOKS LIKE IT SHOULD HOLD FEWER SHOWERS...WITH
LITTLE FORCING AND ONLY WEAK BOUNDARIES RUNNING ABOUT.
THUS...WILL KEEP POPS TO 20S IN THE SW.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
ANOMALOUS UPPER LEVEL RIDGE IS FORECAST TO DOMINATE THE EASTERN
THIRD TO HALF OF THE UNITED STATES TROUGH THE LONG TERM PERIOD.
THIS WILL LEAD TO ABOVE- NORMAL TEMPERATURES FOR MUCH OF THE
PERIOD. THE WARMTH AND INCREASING HUMIDITY SHOULD ALLOW FOR AT
LEAST A SLIGHT CHC OF DIURNAL CONVECTION EACH DAY...BUT WARM MID-
LEVELS WILL KEEP THE PROBABILITY OF WIDESPREAD RAINFALL QUITE LOW.
THE HIEST CHANCES FOR PRECIP WILL BE DURING THE MID-LATE WEEK
PERIOD /WED-THU-FRI/ WITH A COUPLE SUBTLE FEATURES. FIRST...A WEAK
UPPER LEVEL WAVE /BEST PROGGED ON THE ECMWF/ SLIPS OVERHEAD ON WED
AS THE BERMUDA HIGH BRIEFLY RECEDES. AT SAME TIME A WEAK BACKDOOR
COLD FRONT SLIPS SOUTHWARD OFF THE EAST COAST. THIS COULD HELP
POOL SOME LOW LEVEL MOISTURE OVER THE MID ATLANTIC AND OHIO VALLEY
AS MID LEVELS COOL JUST A BIT...BRINGING POTENTIAL FOR SCT TSTMS.
RIDGE BUILDS BACK IN FOR FRI...BUT ANOTHER SURFACE BACKDOOR FRONT
TRIES TO SLIP ACROSS THE STATE AS SURFACE HIGH EXPANDS IN FROM THE
NORTH. THIS BOUNDARY SHOULD BRING SCT CONVECTION FOR FRI.
EXTENDED MODELS HINT AT POTENTIAL FOR DAILY CONVECTION CONTINUING
INTO THE WEEKEND ALONG SOUTHER BORDER...BUT OVERALL CONDITIONS
WILL BE MAINLY RAIN-FREE.
TEMPS PEAK MIDWEEK WITH READINGS APPROACHING 90F IN THE SE...AND
EVEN GETTING INTO THE 80S ELSE HERE...EASILY WELL ABOVE NORMAL
FOR THE FIRST WEEK OF SEPT. LOWS WILL ALSO REMAIN QUITE MILD
MID/LATE WEEK AS HIGH HUMIDITY AIR HANGS AROUND. SLIGHTLY COOLER
BUT STILL ABOVE AVERAGE TEMPS WILL CONTINUE THROUGH THE WEEKEND.
&&
.AVIATION /22Z MONDAY THROUGH SATURDAY/...
SHRA/TSRA OVER THE SC MTNS WILL DIE OFF THIS AFTN/EVENING. MOST
WILL BE GONE BEFORE 22-23Z. FOG IS LIKELY IN THE VALLEYS AND
PERHAPS AOO WHERE IT RAINED TODAY.
HIGH PRESSURE OFF THE EAST COAST WILL REMAIN IN PLACE FOR A FEW
DAYS. RETURN FLOW FROM THE W/SW WILL MAKE IT VERY WARM AND
HUMID...BUT A RIDGE ALOFT WILL SERVE TO SUPPRESS CONVECTION.
THUS...MOST OF THE TIME WILL BE VFR WITH ONLY EARLY AM FOG IN THE
VALLEYS AS IS NORMAL FOR SEPT. AFTN REDUCTIONS IN ISOLD SH/TSRA
ARE POSS THROUGH THE NEXT FEW DAYS...BUT THE MAJORITY OF THE TIME
WILL BE VFR.
OUTLOOK...
WED-SAT...PATCHY AM FOG POSS...MAINLY KIPT/KBFD. ISOLD PM TSRA
IMPACTS POSSIBLE...MAINLY W.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO/DEVOIR
SHORT TERM...DANGELO
LONG TERM...LAMBERT
AVIATION...DANGELO
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
359 PM EDT MON AUG 31 2015
.SYNOPSIS...
A MODERATELY HIGH AMOUNT OF MOISTURE STREAMING EAST FROM THE OHIO
VALLEY WILL EXTEND ACROSS PENN THROUGH MUCH OF THIS WEEK. THE
CLOSE PROXIMITY OF A NEARLY EAST-WEST FRONTAL BOUNDARY ACROSS
PENNSYLVANIA WILL LEAD TO ISOLATED SHOWERS TODAY THROUGH
THURSDAY.
HIGH PRESSURE OFF THE EAST COAST WILL RIDGE NORTHWEST INTO
PENNSYLVANIA AND LEAD TO TEMPERATURES WELL ABOVE NORMAL THIS
ENTIRE WEEK. IT WILL FEEL MORE LIKE THE MIDDLE OF SUMMER THAN
SEPTEMBER.
&&
.NEAR TERM /UNTIL 11 PM THIS EVENING/...
SHOWERS AND ISOLD TSRA OVER THE SRN MTNS ARE DRIFTING ESE. A FEW
OTHER CELLS ARE SPRINKLED ABOUT THE CWA. IN GENERAL...THESE ARE
NOT ALL THAT TALL...BUT AS WE SAW YESTERDAY...THE PWATS ARE
INCHING UP AND 1.5 TO 1.75 INCH VALUES ARE NOT UNCOMMON - MAINLY
IN THE SOUTH. THUS...A FEW MAY CONTAIN HEAVY DOWNPOURS. THE RAP
AND HRRR HAVE ALL OF THE CURRENT SHOWERS DYING A QUICK DEATH VERY
EARLY THIS EVENING - PERHAPS BEFORE SUNSET IN THE CENTRAL COS
WHERE INSTABILITY IS NOT SO GREAT AND SUBSIDENCE/DRYING IS QUITE
EVIDENT. WILL KEEP POPS UNDER 20 THERE AND NORTH FOR THE REST OF
THE AFTN/EVENING.
&&
.SHORT TERM /11 PM THIS EVENING THROUGH 6 PM TUESDAY/...
FOG IS NOT A SLAM-DUNK TONIGHT...BUT HIGH MOISTURE AND CLEARING
SKY SHOULD ALLOW FOR THE VALLEYS TO FOG UP AS IS USUAL IN SEPT.
YES...SEPT ALREADY. WILL ALSO MENTION SOME PATCHY FOG IN THE SRN
TIER WHERE IT IS RAINING. MINS SHOULD RUN IN THE MUGGY 60S AND
L70S AGAIN. TUESDAY LOOKS LIKE IT SHOULD HOLD FEWER SHOWERS...WITH
LITTLE FORCING AND ONLY WEAK BOUNDARIES RUNNING ABOUT.
THUS...WILL KEEP POPS TO 20S IN THE SW.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
ANOMALOUS UPPER LEVEL RIDGE IS FORECAST TO DOMINATE THE EASTERN
THIRD TO HALF OF THE UNITED STATES TROUGH THE LONG TERM PERIOD.
THIS WILL LEAD TO ABOVE- NORMAL TEMPERATURES FOR MUCH OF THE
PERIOD. THE WARMTH AND INCREASING HUMIDITY SHOULD ALLOW FOR AT
LEAST A SLIGHT CHC OF DIURNAL CONVECTION EACH DAY...BUT WARM MID-
LEVELS WILL KEEP THE PROBABILITY OF WIDESPREAD RAINFALL QUITE LOW.
THE HIEST CHANCES FOR PRECIP WILL BE DURING THE MID-LATE WEEK
PERIOD /WED-THU-FRI/ WITH A COUPLE SUBTLE FEATURES. FIRST...A WEAK
UPPER LEVEL WAVE /BEST PROGGED ON THE ECMWF/ SLIPS OVERHEAD ON WED
AS THE BERMUDA HIGH BRIEFLY RECEDES. AT SAME TIME A WEAK BACKDOOR
COLD FRONT SLIPS SOUTHWARD OFF THE EAST COAST. THIS COULD HELP
POOL SOME LOW LEVEL MOISTURE OVER THE MID ATLANTIC AND OHIO VALLEY
AS MID LEVELS COOL JUST A BIT...BRINGING POTENTIAL FOR SCT TSTMS.
RIDGE BUILDS BACK IN FOR FRI...BUT ANOTHER SURFACE BACKDOOR FRONT
TRIES TO SLIP ACROSS THE STATE AS SURFACE HIGH EXPANDS IN FROM THE
NORTH. THIS BOUNDARY SHOULD BRING SCT CONVECTION FOR FRI.
EXTENDED MODELS HINT AT POTENTIAL FOR DAILY CONVECTION CONTINUING
INTO THE WEEKEND ALONG SOUTHER BORDER...BUT OVERALL CONDITIONS
WILL BE MAINLY RAIN-FREE.
TEMPS PEAK MIDWEEK WITH READINGS APPROACHING 90F IN THE SE...AND
EVEN GETTING INTO THE 80S ELSE HERE...EASILY WELL ABOVE NORMAL
FOR THE FIRST WEEK OF SEPT. LOWS WILL ALSO REMAIN QUITE MILD
MID/LATE WEEK AS HIGH HUMIDITY AIR HANGS AROUND. SLIGHTLY COOLER
BUT STILL ABOVE AVERAGE TEMPS WILL CONTINUE THROUGH THE WEEKEND.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
SHRA/TSRA OVER THE SC MTNS WILL DIE OFF THIS AFTN/EVENING. MOST
WILL BE GONE BEFORE 22-23Z. FOG IS LIKELY IN THE VALLEYS AND
PERHAPS AOO WHERE IT RAINED TODAY.
HIGH PRESSURE OFF THE EAST COAST WILL REMAIN IN PLACE FOR A FEW
DAYS. RETURN FLOW FROM THE W/SW WILL MAKE IT VERY WARM AND
HUMID...BUT A RIDGE ALOFT WILL SERVE TO SUPPRESS CONVECTION.
THUS...MOST OF THE TIME WILL BE VFR WITH ONLY EARLY AM FOG IN THE
VALLEYS AS IS NORMAL FOR SEPT. AFTN REDUCTIONS IN ISOLD SH/TSRA
ARE POSS THROUGH THE NEXT FEW DAYS...BUT THE MAJORITY OF THE TIME
WILL BE VFR.
OUTLOOK...
WED-SAT...PATCHY AM FOG POSS...MAINLY KIPT/KBFD. ISOLD PM TSRA
IMPACTS POSSIBLE...MAINLY W.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...LAMBERT
AVIATION...DANGELO
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
308 PM EDT MON AUG 31 2015
.SYNOPSIS...
A MODERATELY HIGH AMOUNT OF MOISTURE STREAMING EAST FROM THE OHIO
VALLEY WILL EXTEND ACROSS PENN THROUGH MUCH OF THIS WEEK. THE
CLOSE PROXIMITY OF A NEARLY EAST-WEST FRONTAL BOUNDARY ACROSS
PENNSYLVANIA WILL LEAD TO ISOLATED SHOWERS TODAY THROUGH
THURSDAY.
HIGH PRESSURE OFF THE EAST COAST WILL RIDGE NORTHWEST INTO
PENNSYLVANIA AND LEAD TO TEMPERATURES WELL ABOVE NORMAL THIS
ENTIRE WEEK. IT WILL FEEL MORE LIKE THE MIDDLE OF SUMMER THAN
SEPTEMBER.
&&
.NEAR TERM /UNTIL 11 PM THIS EVENING/...
SHOWERS AND ISOLD TSRA OVER THE SRN MTNS ARE DRIFTING ESE. A FEW
OTHER CELLS ARE SPRINKLED ABOUT THE CWA. IN GENERAL...THESE ARE
NOT ALL THAT TALL...BUT AS WE SAW YESTERDAY...THE PWATS ARE
INCHING UP AND 1.5 TO 1.75 INCH VALUES ARE NOT UNCOMMON - MAINLY
IN THE SOUTH. THUS...A FEW MAY CONTAIN HEAVY DOWNPOURS. THE RAP
AND HRRR HAVE ALL OF THE CURRENT SHOWERS DYING A QUICK DEATH VERY
EARLY THIS EVENING - PERHAPS BEFORE SUNST IN THE CENTRAL COS
WHERE INSTABILITY IS NOT SO GREAT AND SUBSIDENCE/DRYING IS QUITE
EVIDENT. WILL KEEP POPS UNDER 20 THERE AND NORTH FOR THE REST OF
THE AFTN/EVENING.
&&
.SHORT TERM /11 PM THIS EVENING THROUGH 6 PM TUESDAY/...
FOG IS NOT A SLAM-DUNK TONIGHT...BUT HIGH MOISTURE AND CLEARING
SKY SHOULD ALLOW FOR THE VALLEYS TO FOG UP AS IS USUAL IN SEPT.
YES...SEPT ALREADY. WILL ALSO MENTION SOME PATCHY FOG IN THE SRN
TIER WHERE IT IS RAINING. MINS SHOULD RUN IN THE MUGGY 60S AND
L70S AGAIN. TUESDAY LOOKS LIKE IT SHOULD HOLD FEWER SHOWERS...WITH
LITTLE FORCING AND ONLY WEAK BOUNDARIES RUNNING ABOUT.
THUS...WILL KEEP POPS TO 20S IN THE SW.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
ANOMALOUS UPPER LEVEL RIDGE WILL DOMINATE THE OHIO VALLEY AND
EASTERN UNITED STATES MUCH OF THE UPCOMING WEEK...WITH LATEST
GUIDANCE REMAINING FIRM FOR AN EXTENDED RUN OF 850HPA TEMPS
PEAKING DAILY AROUND 16-18C. THIS WILL TRANSLATE TO WELL ABOVE-
NORMAL SFC TEMPS. THIS WARMTH AND INCREASING HUMIDITY SHOULD ALLOW
FOR AT LEAST A SLIGHT CHC FOR DIURNAL CONVECTION EACH DAY...BUT
WARM MID-LEVELS WILL KEEP THE PROBABILITY OF WIDESPREAD RAINFALL
QUITE LOW.
BEST CHANCES FOR PRECIP WILL BE DURING THE MID-LATE WEEK PERIOD
/WED-THU-FRI/ WITH A COUPLE SUBTLE FEATURES. FIRST...A WEAK UPPER
LEVEL WAVE /BEST PROGGED ON THE ECMWF/ SLIPS OVERHEAD ON WED AS
BERMUDA HIGH BRIEFLY RECEDES. AT SAME TIME A WEAK BACKDOOR COLD
FRONT SLIPS SOUTHWARD OFF THE EAST COAST. THIS COULD HELP POOL
SOME LOW LEVEL MOISTURE OVER THE MID ATLANTIC AND OHIO VALLEY AS
MID LEVELS COOL JUST A BIT...BRINGING POTENTIAL FOR SCT TSTMS.
RIDGE BUILDS BACK IN FOR FRI...BUT ANOTHER SURFACE BACKDOOR FRONT
TRIES TO SLIP ACROSS THE STATE AS SURFACE HIGH EXPANDS IN FROM THE
NORTH. THIS BOUNDARY SHOULD BRING SCT CONVECTION FOR FRI.
EXTENDED MODELS HINT AT POTENTIAL FOR DAILY CONVECTION CONTINUING
INTO THE WEEKEND ALONG SOUTHER BORDER...BUT OVERALL CONDITIONS
WILL BE MAINLY RAIN-FREE.
TEMPS PEAK MIDWEEK WITH READINGS APPROACHING 90F IN THE SE...AND
EVEN GETTING INTO THE 80S ELSE HERE...EASILY WELL ABOVE NORMAL
FOR THE FIRST WEEK OF SEPT. LOWS WILL ALSO REMAIN QUITE MILD
MID/LATE WEEK AS HIGH HUMIDITY AIR HANGS AROUND. SLIGHTLY COOLER
BUT STILL ABOVE AVERAGE TEMPS WILL CONTINUE THROUGH THE WEEKEND.
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
SHRA/TSRA OVER THE SC MTNS WILL DIE OFF THIS AFTN/EVENING. MOST
WILL BE GONE BEFORE 22-23Z. FOG IS LIKELY IN THE VALLEYS AND
PERHAPS AOO WHERE IT RAINED TODAY.
HIGH PRESSURE OFF THE EAST COAST WILL REMAIN IN PLACE FOR A FEW
DAYS. RETURN FLOW FROM THE W/SW WILL MAKE IT VERY WARM AND
HUMID...BUT A RIDGE ALOFT WILL SERVE TO SUPPRESS CONVECTION.
THUS...MOST OF THE TIME WILL BE VFR WITH ONLY EARLY AM FOG IN THE
VALLEYS AS IS NORMAL FOR SEPT. AFTN REDUCTIONS IN ISOLD SH/TSRA
ARE POSS THROUGH THE NEXT FEW DAYS...BUT THE MAJORITY OF THE TIME
WILL BE VFR.
OUTLOOK...
WED-SAT...PATCHY AM FOG POSS...MAINLY KIPT/KBFD. ISOLD PM TSRA
IMPACTS POSSIBLE...MAINLY W.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...LAMBERT/RXR
AVIATION...DANGELO
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1109 AM MDT MON AUG 31 2015
.UPDATE...
ISSUED AT 852 AM MDT MON AUG 31 2015
UPPER WAVE CONTINUES TO PUSH THROUGH THE NORTHERN PLAINS. RADAR
STILL INDICATES SHOWER ACTIVITY BEHIND THE COLD FRONT ACROSS
SOUTHWEST INTO CENTRAL SD. ADDED SOME ISOLATED SHOWERS THROUGH
THE DAY FOR ANY RAIN THAT MIGHT BE REACHING THE GROUND...ALTHOUGH
OBS STILL SHOW PRETTY DRY AIR SO IT MAY REMAIN VIRGA. INCREASED
CLOUD COVER TO REFLECT CURRENT TRENDS...BUT REST OF FORECAST LOOKS
ON TRACK FOR NOW.
&&
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
ISSUED AT 327 AM MDT MON AUG 31 2015
WATER VAPOR IMAGERY SHOWS STRONG UPPER WAVE CROSSING CNTRL TO ERN MT
INTO NRN WY. SURFACE ANALYSIS SHOWS LOW PRES ACROSS THE WRN/CNTRL
DAKOTAS AHEAD OF THE UPPER WAVE...WITH A COLD FRONT QUICKLY PUSHING
THRU ERN MT/CNTRL WY TOWARD THE CWA. TEMPS ACROSS THE CWA ARE IN THE
60S/70S...EVEN 80S ACROSS THE DOWNSLOPING N/NE BLKHLS. BEHIND THE
FRONT...OBS SHOWING TEMPS DROPPING INTO THE 50S WITH WINDS OF 15 TO
30 GUSTING TO 30 TO 40 MPH. RADAR SHOWS SHOWER ACTIVITY CROSSING WRN
SD...HOWEVER NEARLY ALL THE PRECIP IS VIRGA WITH LITTLE TO NO RAIN
REACHING THE GROUND. THE COLD FRONT WILL PUSH THROUGH NE WY TO WRN
SD IN THE NEXT 4/5 HOURS OR SO...AND CLEAR SCNTRL SD BY MID TO LATE
MORNING. HRRR SUGGESTS WINDS WILL GENERALLY BE 15 TO 25 MPH WITH
GUSTS TO 30 TO 40 MPH...BUT IS ALSO SHOWING STRONGER WINDS ACROSS
THE WRN SD PLAINS NORTH AND EAST OF THE BLKHLS. WIND ADVISORY
CRITERIA WINDS ARE EXPECTED...HOWEVER JUST FOR COUPLE HOURS OR SO
IMMEDIATELY AFTER THE FROPA. COULD SEE LINGERING SHRA ACTIVITY EARLY
THIS MORNING AS MODELS ARE HAVING A HARD TIME DECIDING HOW MUCH
PRECIP WILL REACH THE GROUND. WILL LEAN TOWARD A DRY FORECAST FOR
NOW CONSIDERING THE LATEST RADAR IMAGERY...BUT WILL REASSESS CLOSER
TO 12Z. OTHERWISE A DRY DAY IS EXPECTED WITH MUCH COOLER
TEMPERATURES AND CLEARING SKIES. HIGHS WILL REACH THE UPPER 70S TO
UPPER 80S. TEMPS TONIGHT WILL DROP INTO THE 50S TO LOWER 60S. RETURN
FLOW WILL SET UP BY MON NIGHT/TUE MRNG WITH WARMER TEMPS
EXPECTED. HIGHS WILL RETURN TO THE MID 80S TO MID 90S. DRY WEATHER
WILL CONTINUE TUE/TUE NIGHT WITH BROAD SWRLY FLOW ALOFT
PERSISTING.
.LONG TERM...WEDNESDAY THROUGH SUNDAY
ISSUED AT 327 AM MDT MON AUG 31 2015
THE UPPER TROUGH WILL REMAIN OVER THE NORTH AMERICAN PACIFIC
COAST THROUGH MOST OF THE WEEK...EVENTUALLY MOVING INLAND BY THE
WEEKEND AS ANOTHER IMPULSE DROPS INTO THE UPPER TROUGH FROM THE
NORTHWEST. THIS PATTERN WILL LEAD TO CONTINUED VERY WARM
TEMPERATURES OVER THE NORTHERN PLAINS BOTH WEDNESDAY AND THURSDAY.
FRIDAY AND SATURDAY WILL BE SLIGHTLY COOLER...WITH MUCH COOLER
TEMPS ON SUNDAY AND MONDAY BEHIND A RELATIVELY STRONG COLD FRONT
WHICH WILL PASS THROUGH THE AREA EARLY SUNDAY. DRY WEATHER IS
EXPECTED ON WEDNESDAY AND THURSDAY WITH A CHANCE OF THUNDERSTORMS
EACH DAY FROM FRIDAY THROUGH THE WEEKEND AS A SERIES OF UPPER
IMPULSES CROSS THE REGION AND COOLER AIR FLOWS IN AT THE SFC.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY)
ISSUED AT 1105 AM MDT MON AUG 31 2015
VFR CONDITIONS EXPECTED THROUGH THE PERIOD. A NARROW BAND OF -SHRA
WILL MOVE ACROSS SCNTRL SD THROUGH THIS AFTN. GUSTY NORTHWEST
WINDS ACROSS THE SD PLAINS WILL DIMINISH THIS AFTN.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
UPDATE...POJORLIE
SHORT TERM...13
LONG TERM...10
AVIATION...BUNKERS
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
338 PM CDT MON AUG 31 2015
.SHORT TERM...
(Tonight and Tuesday)
The afternoon cumulus field development is well underway. The TTU
WRF and HRRR models continue to suggest isolated convection will
develop across the southeast third of the forecast area, or roughly
south and east of a Sonora to Eden to Brownwood line during the next
few hours, with any convection dissipating after sunset.
Temperatures dropped to near 60 degrees last night in low-lying
areas under clear skies and light winds. Given the dry soil
conditions in place with similar conditions expected tonight, we
went a couple degrees under guidance to account for this. Sunny
skies and afternoon cumulus are expected for Tuesday, with high
temperatures similar to today, generally in the lower to mid 90s.
.LONG TERM...
(Wednesday through Tuesday)
Weak upper level ridge in place across the area will gradually
strengthen across West Central Texas through the period. Low level
thickness and temperature fields are not forecasted by the models
to climb nearly as high as when the last upper level ridge was in
place, but still should be strong enough to keep temperatures at or
a few degrees above normal for the entire extended. Ridge really
nor forecasted to budge much through the entire first 10 days of
September, so it looks like a quiet extended forecast will
continue.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 69 94 71 94 / 0 5 0 0
San Angelo 69 95 70 95 / 5 5 5 5
Junction 67 93 69 91 / 10 5 5 5
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Doll/07
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
1235 PM CDT MON AUG 31 2015
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...SHOWER AND THUNDERSTORM ACTIVITY BEGINNING TO POP UP
NEAR KBRO AND KHRL...WITH SOME WELL-DEFINED LOWERED CIGS IN THEIR
WAKE. ACTIVITY WILL SPREAD INLAND...REACHING KMFE LATER THIS
AFTERNOON. MADE MINOR TWEAKS TO SKY COVER...BUT OTHERWISE CLOUD
AND SHOWER WORDING REMAINS THE SAME. LOW CLOUDS SHOULD BREAK UP
THIS EVENING WHILE WINDS DECREASE TO AROUND 5KTS. A FEW SHOWERS
MAY AGAIN DRIFT NORTHWARD ACROSS KBRO AND MAYBE KHRL JUST BEFORE
DAWN...SIMILAR TO TODAY.
&&
.PREV DISCUSSION... /ISSUED 637 AM CDT MON AUG 31 2015/
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
AVIATION...CURRENT RADAR SHOWS CONVECTION MOVING ASHORE FROM THE
GULF WATERS AND HAS IMPACTED BRO RECENTLY WITH ANOTHER BAND ON THE
MOVE TOWARDS THE LOWER VALLEY. CONVECTION WILL INCREASE IN
COVERAGE TODAY WITH A GOOD POSSIBILITY OF THE AERODROMES
EXPERIENCING SHOWERS AND STORMS TODAY. EXPECT TEMPO MVFR CONDS AND
POSSIBLY HIGH IFR UNDER THE STRONGER STORMS. CONVECTION WILL END
THIS EVENING.
PREV DISCUSSION... /ISSUED 358 AM CDT MON AUG 31 2015/
SHORT TERM /TODAY THROUGH TUESDAY/...FORECAST CHALLENGE FOR THE SHORT
TERM WILL BE PRECIPITATION CHANCES AND PLACEMENT.
EARLY MORNING WATER VAPOR IMAGERY DEPICTS A MID LEVEL LOW PRESSURE
AREA SPINNING NICELY ACROSS SOUTH CENTRAL TEXAS WITH A FINGER OF DRY
AIR ADVECTING INTO TO THE WESTERN CWA ON THE SOUTHSIDE OF THIS
FEATURE. TIME HEIGHTS SHOW THIS DRY AIR NICELY IN THE 600-400MB
LAYER. THIS LOW PRESSURE AREA IS LOCATED WITHIN A BROAD TROUGH
EXTENDING FROM NORTHEAST MEXICO NORTHEASTWARD THROUGH EASTERN
ARKANSAS. PWAT ON THE 00Z BRO SOUNDING WAS 1.93 INCHES WITH EVEN
HIGHER PWATS SOUTHWARD INTO THE BAY OF CAMPECHE ACCORDING TO BLENDED
TPW PRODUCTS. AT THIS HOUR CONVECTION IN THE GULF IS INCREASING
AHEAD OF DEEPER MOISTURE AND LARGE SCALE LIFT.
TROUGH AXIS WILL MOVE SLOWLY EASTWARD TODAY FROM ITS PRESENT
LOCATION LEAVING THE AREA IN FAVORABLE LARGE SCALE LIFT. MID LEVEL
DRY AIR WILL QUICKLY MOISTEN THROUGH THE MORNING HOURS WITH
FAVORABLE SFC-700MB MOISTURE PROFILE. LOOKING UPSTAIRS AT
250MB...THERE IS SOME WEAK SPEED DIFFLUENCE IN CYCLONIC FLOW SOUTH
OF THE LOW AND TROUGH AXIS. NOT MUCH TO HANG YOUR HAT ON AT THE
SURFACE EXCEPT FOR WEAK SPEED AND DIRECTIONAL CONVERGENCE SO THE
SEABREEZE WILL BECOME ACTIVE LATER THIS MORNING WITH CONVECTION
SPREADING WESTWARD WITH TIME. HRRR SHOWS INITIATION IN THE COASTAL
SECTIONS AROUND 16Z THEN SPREADING WESTWARD AND I FOLLOWED THIS
TREND. EXPECT SCATTERED COVERAGE OF CONVECTION WITH BRIEF HEAVY
RAINFALL AND GUSTY WINDS CORRESPONDING TO INVERTED-V FORECAST
SOUNDINGS ACROSS MUCH OF THE AREA.
CONVECTION WILL WANE IN THE EVENING HOURS REACHING THE FAR WESTERN
SECTIONS. HIGHER PWAT AND MOISTURE WILL BE ADVECTED ACROSS THE AREA
TONIGHT INTO TUESDAY. DEEPER MOISTURE ARRIVES AS THE LARGE SCALE
LIFT MOVES EAST OF THE AREA AND THE TROUGH AXIS IS DIRECTLY
OVERHEAD. THEREFORE...LARGE SCALE LIFT IS NEUTRAL. CONVECTION WILL
GET GOING OVERNIGHT ONCE AGAIN ACROSS THE GULF WATERS THEN SPREAD
INLAND AND DEVELOP ON THE SEABREEZE ONCE AGAIN. A LITTLE COOLER MID
LEVEL TEMPERATURES WILL LEAD TO SLIGHTLY BETTER CAPES AND
INSTABILITY. GUSTY WINDS AND HEAVY DOWNPOURS WILL BE OF CONCERN ONCE
AGAIN TUESDAY.
LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...500MB TROUGH AXIS TO
LINGER ALONG THE TEXAS COAST EXTENDING INTO THE RGV WEDNESDAY
THEN SHIFT EASTWARD THURSDAY BEFORE SOME OF THE ENERGY SPLITS AND
THE SOUTHERN END OF THE TROUGH TAKES ON A RETROGRADING TRACK AS AN
INVERTED TROUGH FRIDAY INTO SATURDAY. GFS ENSEMBLE MEAN AND
DETERMINISTIC MODELS ARE MORE DISTINCT WITH THE SOUTHERN ENERGY
/INVERTED TROUGH/ WITH WITH THE ECMWF NOT AS TRANSPARENT
INDICATING MORE ENERGY REMAINING WITH THE TROUGH RESIDING OVER THE
SE U.S. MOISTURE FIELDS AND POPS GUIDANCE TREND DOWN WEDNESDAY AND
THURSDAY FROM THE HIGH POPS OF MONDAY AND TUESDAY. GFS/MAV TRENDS
UP FRIDAY AS THE INVERTED TROUGH APPROACHES. ECMWF CONTINUES TO
HAVE A HIGH POP BIAS BUT SHOWS A DOWNWARD TREND THROUGH THE WEEK.
THE FORECAST IS LEANING MORE WITH GFS AND ITS STRONGER SOUTHERN
INVERTED TROUGH FEATURE WITH BOTH THE EMSEMBLE AND DETERMINISTIC
SOLUTIONS IN BETTER AGREEMENT THEN THE DIVERGING OR WEAKER ECMWF.
FORECAST TAKES ON A GENERAL MIDDLE OF THE ROAD TREND WITH
ISOLATED TO SCATTERED CONVECTION WITH WEDNESDAY AND FRIDAY AND
POSSIBLY NEXT SATURDAY SEEING THE HIGHEST CHANCES BETTER OVERALL
AREAL COVERAGE. DIFFICULT TO PINPOINT IF THE EAST WILL SEE MORE
PRECIPITATION THAN THE WEST ON ANY PARTICULAR DAY AS WE MOVE INTO
OUR RAINIEST MONTH. MODELS SUGGEST AN AVERAGE MOISTURE CONTENT
THROUGH THE ATMOSPHERIC COLUMN WITH PWATS AROUND 1.75 INCH RANGE.
DO NOT SEE ANY DEEP TROPICAL MOISTURE THAT WOULD RAISE THE CONCERN
OF HEAVY RAIN AT THIS TIME BUT ISOLATED DOWNPOURS ARE NOT OUT OF
QUESTION WITH ANY STORMS THAT DO DEVELOP. TEMPERATURES TO AVERAGE
NEAR SEASONAL NORMALS WITH NO EXTREMES INDICATED.
MARINE...NOW THROUGH TUESDAY...WEAK HIGH PRESSURE WILL SUPPORT
LIGHT TO MODERATE SOUTHEAST WINDS AND LOW SEAS. SHOWERS AND
THUNDERSTORMS WILL INCREASE TODAY THROUGH TUESDAY DUE TO
INSTABILITY ALOFT AND INCREASED MOISTURE MOVING UP FROM SOUTH OF
THE AREA.
TUESDAY NIGHT THROUGH FRIDAY...BROAD HIGH PRESSURE TO REMAIN OVER
THE GULF WITH A WEAK UPPER LEVEL TROUGH OVER THE NORTHWEST AND
NORTH CENTRAL GULF. LIGHT ONSHORE WINDS AND SLIGHT SEAS TO PERSIST
INTO THURSDAY. A MID LEVEL INVERTED TROUGH TO TRACK THROUGH THE
LOWER TEXAS COASTAL WATERS FRIDAY INTO SATURDAY WIND A SLIGHT
INCREASE OF ONSHORE WINDS AND SLIGHT UPTICK OF SEAS. DAILY SHOWERS
AND THUNDERSTORMS ARE EXPECTED WITH BEST CHANCES WEDNESDAY AND
FRIDAY.
BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
64
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1225 PM CDT MON AUG 31 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 340 AM CDT MON AUG 31 2015
EARLY THIS MORNING...LOW STRATUS HAS QUICKLY DEVELOPED ACROSS
NORTH-CENTRAL IA AND ALONG THE MN/IA BORDER AS WELL AS ACROSS
NORTHERN WI. 31.07Z RAP SHOWS THIS STRATUS FILLING-IN ACROSS MUCH
OF THE FORECAST AREA BY SUNRISE. THESE CLOUDS...COMBINED WITH
BRISK WEST-SOUTHWEST WIND JUST OFF THE SURFACE SHOULD PRECLUDE
WIDESPREAD DENSE FOG...BUT CAN STILL EXPECT SOME AREAS OF REDUCED
VISIBILITY...ESPECIALLY FOR THOSE AREAS THAT REMAIN MOSTLY CLEAR
FOR A LONGER PERIOD.
AS QUICKLY AS THE STRATUS DEVELOPS...MOST HIGH RESOLUTION MODELS
DISSIPATE IT JUST AS QUICKLY BY LATE MORNING AS 15 TO 20 KTS MIX
WITHIN DEEPENING BOUNDARY LAYER. EXPECT A RETURN TO AT LEAST
PARTLY SUNNY SKIES BY EARLY AFTERNOON. PRIMARY IMPACT OF CLOUDS
WILL BE TO SLOW TEMPERATURE RISE THROUGH THE DAY...SO DROPPED
AFTERNOON HIGHS A FEW DEGREES INTO THE LOWER TO MID 80S.
TONIGHT NOT LIKELY TO BE COMPLETELY CLOUD FREE AND WITH 10 TO 20
KTS ATOP NOCTURNAL INVERSION...FOG THREAT SHOULD BE LOWER THAN THE
PAST COUPLE NIGHTS. TEMPERATURES WILL DROP INTO THE MID TO UPPER
60S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 340 AM CDT MON AUG 31 2015
MAIN STORY FOR THE WEEK CONTINUES TO BE WELL ABOVE NORMAL
TEMPERATURES WITH A BROAD 500 HPA RIDGE PARKED ACROSS THE EASTERN
CONUS. WITH 925 HPA TEMPERATURES GENERALLY WOBBLING BETWEEN 24 AND
26 CELSIUS...DAILY HIGHS HIGHS WILL TOP OUT IN THE MID TO UPPER
80S WITH SOME 90 PLUS DEGREE READINGS ALONG AND EAST OF THE MS
RIVER.
WILL KEEP 20-30 PERCENT MODEL CONSENSUS POPS WEDNESDAY NIGHT
THROUGH FRIDAY...BUT THINK MAJORITY OF THE WEEK WILL REMAIN DRY.
MULTIPLE WEAK/ILL-RESOLVED SHORT-WAVES MOVE ACROSS THE REGION IN
SOUTHWEST FLOW ALOFT THAT COULD PROVIDE A FOCUSING MECHANISM FOR
CONVECTION. HOWEVER...AXIS OF MAXIMUM MID-LEVEL MOISTURE TRANSPORT
REMAINS WEST OF THE FORECAST AREA...CLOSER TO THE WESTERN CONUS
TROUGH. DAILY INSTABILITY IS PRESENT WITH ABOVE NORMAL TEMPERATURES/
SURFACE DEWPOINTS IN THE 60S...BUT LARGE SCALE RIDGE SQUASHES ANY
DEEP LAYER SHEAR OF SIGNIFICANCE. FOR NOW...DIFFICULT TO PROVIDE
DETAILS ON TIMING OR COVERAGE IF ANYTHING DOES DEVELOP SO BROAD-
BRUSHED POPS SEEM REASONABLE.
BETTER CHANCES FOR SHOWERS AND THUNDERSTORMS RETURN SATURDAY NIGHT
INTO SUNDAY AS 31.00Z GFS/ECMWF ATTEMPT TO BREAK DOWN EASTERN
CONUS RIDGE BY MOVING A BROAD PACIFIC TROUGH INTO THE ROCKIES/
NORTHERN PLAINS. GFS IS MUCH QUICKER IN DOING SO COMPARED TO THE
SLOWER ECMWF...SO DEFINITE TIMING ISSUES EMERGE. FOR NOW...A
BLENDED APPROACH IS PRUDENT RESULTING IN CHANCE POPS SATURDAY
NIGHT THROUGH THE DAY ON SUNDAY. SHOULD SEE TEMPERATURES FALL BACK
TO MORE SEASONABLE LEVELS ONCE TROUGH PASSES...BUT WHETHER THIS
OCCURS BY SUNDAY OR EARLY NEXT WEEK IS YET TO BE SEEN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1225 PM CDT MON AUG 31 2015
INCREASING SOUTH-SOUTHWEST LOWER LEVEL FLOW WAS ALLOWING FOR MORE
MIXING TODAY...WITH THE MVFR/IFR STRATO-CU DECK ERODING/LIFTING
NORTH OF THE TAF SITES BY 17Z TODAY. MORE DIURNAL WARMING/DEEPER
MIXING THIS AFTERNOON SHOULD RAISE SCT CUMULUS HGTS INTO THE 2500 FT
RANGE FOR THE AFTERNOON. SOUNDINGS/X-SECTIONS THEN SHOW DRYING BELOW
900MB IN THE SOUTHWEST FLOW FOR TONIGHT INTO TUE...WITH A MOISTURE
INCREASE TONIGHT AROUND 850MB OR ABOUT 4000 FT AGL. CARRIED THIS AS
A SCT035/SCT040 DECK AT KRST/KLSE RESPECTIVELY FOR TONIGHT-TUE
MORNING. WITH A MOIST BOUNDARY LAYER AIRMASS AND NOCTURNAL
COOLING...CONTINUED A MENTION OF SOME MVFR BR DURING THE LATE NIGHT
AND EARLY MORNING HOURS...MAINLY 08Z-14Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...ROGERS
LONG TERM....ROGERS
AVIATION.....RRS