Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 08/03/14
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
854 PM MDT SAT AUG 2 2014
.UPDATE...
ISSUED AT 854 PM MDT SAT AUG 2 2014
LATEST RADAR SHOWS ISOLATED SHOWERS/STORMS CONTINUING OVER THE
NORTHEAST CORNER OF THE STATE WHILE IN THE MOUNTAINS THEY HAVE
MOSTLY DISSIPATED. THE SHOWERS/STORMS ON THE NORTHEAST PLAINS MAY
LINGER FOR ANOTHER COUPLE HOURS AS WEAK OUTFLOW BOUNDARY PUSHES
BACK INTO THE STATE...BUT BY MIDNIGHT SHOULD ALL BE OVER AS TEMPS
ALOFT ARE WARMING. OVERALL FORECAST RIGHT ON TRACK.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 338 PM MDT SAT AUG 2 2014
THE AIRMASS IS DRY OVER THE MOUNTAINS AND FRONT RANGE WHERE
PRECIPITABLE WATER VALUES ARE A HALF INCH OR LESS. STILL COULD SEE A
FEW WEAK STORMS THROUGH EARLY EVENING OVER THE HIGHER
TERRAIN...MAINLY SOUTH OF I-70 WHERE THE MOISTURE IS A LITTLE
GREATER.
SATELLITE SHOWING CUMULUS CLOUDS OVER THE EASTERN PLAINS. CAPES WILL
CLIMB TO AROUND 500 J/KG BASED ON THE RAP AND PRECIPITABLE WATER
WILL BE JUST LESS THAN INCH. BECAUSE OF THIS AND THAT THE HRRR/HIRES
MODELS ARE SHOWING CONVECTION...DECIDED TO EXPAND THE LOW POPS
ACROSS THE EASTERN PLAINS THROUGH 03Z. IF ANY STORMS FORM...EXPECT
THEM TO BE WEAK AND SHORT LIVED.
ONCE THE CONVECTION DIES OFF...EXPECT MOSTLY CLEAR SKIES TONIGHT AND
SUNDAY MORNING. AIRMASS WILL SLOWLY WARM OVER THE NEXT 24 HOURS.
EXPECT LOWS TONIGHT ALONG WITH THE HIGHS SUNDAY AFTERNOON TO BE A
FEW DEGREES WARMER. MOISTURE WILL INCREASE OVER THE MOUNTAINS
SUNDAY...SO EXPECT A LITTLE BETTER CHANCE OF STORMS...SCATTERED AT
BEST. SMALL HAIL...BRIEF MODERATE RAIN AND GUSTY WINDS WILL
ACCOMPANY THE STRONGER STORMS. OVER THE PLAINS...AIRMASS WILL BE A
LITTLE DRIER AND LESS UNSTABLE. WILL JUST HAVE A SLIGHT CHANCE OVER
THE FAR NORTHEAST CORNER OF COLORADO AND LEAVE OUT THE MENTION OF
STORMS ELSEWHERE.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 338 PM MDT SAT AUG 2 2014
UPPER RIDGING OVER THE STATE SUNDAY NIGHT WILL WEAKEN THROUGH
MONDAY AND TUESDAY AS A WEAK UPPER TROUGH MOVES OUT OF THE GREAT
BASIN AND OVER WYOMING. MID-LEVEL MOISTURE WILL INCREASE OVER THE
STATE. SHOWERS OVER THE MOUNTAINS STARTING MONDAY MORNING WILL
SPREAD OUT ONTO THE PLAINS MONDAY AFTERNOON. AS THE WEAK UPPER
TROUGH SLOWLY MOVES TOWARD THE NORTHERN PLAINS ON
TUESDAY...UNSETTLED WEATHER SHOULD CONTINUE ACROSS COLORADO.
MOIST SOUTHWEST FLOW AT MID LEVELS WILL CONTINUE THROUGH THE
REMAINDER OF THE WEEK AS AN UPPER RIDGE REBUILDS OVER THE
SOUTHWESTERN UNITED STATES. TEMPERATURES SHOULD REMAIN SLIGHTLY
COOLER THAN NORMAL THROUGH THE FORECAST PERIOD. SHOWER ACTIVITY
WILL HAVE THE THREAT OF PRODUCING LOCALLY HEAVY RAIN AT TIMES DUE
TO THE SUBTROPICAL NATURE OF THE AIRMASS AND SLOW PROGRESSION OF
INDIVIDUAL STORMS. MOUNTAIN AREAS WILL SEE A CHANCE OF
THUNDERSTORMS THROUGH THE WEEK WHILE THE PLAINS SEE A LITTLE BIT
DRIER WEATHER AFTER TUESDAY.
&&
.AVIATION...(FOR THE TAFS THROUGH 06Z SUNDAY EVENING)
ISSUED AT 854 PM MDT SAT AUG 2 2014
NO WEATHER CONCERNS THROUGH SUNDAY EVENING AS AIRMASS WILL REMAIN
TOO DRY AND STABLE FOR ANY STORM DEVELOPMENT. NORMAL DIURNAL WIND
PATTERNS WILL PREVAIL.
&&
.HYDROLOGY...
ISSUED AT 338 PM MDT SAT AUG 2 2014
DUE TO A DRY AIRMASS...ANY STORMS THAT FORM OVER THE HIGHER TERRAIN
TODAY AND SUNDAY WILL ONLY PRODUCE LIGHT TO MODERATE RAINFALL.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BARJENBRUCH
SHORT TERM...MEIER
LONG TERM...DANKERS
AVIATION...BARJENBRUCH
HYDROLOGY...MEIER
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1155 PM MDT THU JUL 31 2014
.UPDATE...
ISSUED AT 540 PM MDT THU JUL 31 2014
UPDATED FORECAST FOR LATEST RADAR AND MODEL TRENDS. SPOTTY
CONVECTION SHOULD REMAIN MAINLY OVER THE SAN LUIS
VALLEY...CONTDVD...AND ERN MTS THIS EVENING...AND SHOULD
GRADUALLY DISSIPATE AFTER SUNSET. HAVE REMOVED MENTIONABLE
POPS FOR THE PLAINS AS THE PROBABILITY LOOKS FAIRLY LOW
E OF THE MTS. REST OF FORECAST ON TRACK. ROSE
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 229 PM MDT THU JUL 31 2014
CURRENTLY...STORMS HAVE DEVELOPED OVER THE CONTINENTAL DIVIDE
REGION AND HEADED SOUTHEAST. ONCE THE STORMS MOVE INTO TELLER
COUNTY OR CROSS THE SANGRES...THEY WEAKEN QUICKLY. COOL STABLE
AIRMASS IS OVER PORTIONS OF EASTERN MOUNTAINS AND EASTWARD
SUPPRESSING CONVECTION. WEAK UPSLOPE FLOW AND THE ABUNDANT LOW
LEVEL MOISTURE HAS KEPT PERSISTENT CLOUD OVER OVER THE EASTERN
MOUNTAINS AND MUCH OF THE I25 CORRIDOR....WHICH HAS KEPT THE
ATMOSPHERE STABLE OVER TELLER COUNTY AND THE EASTERN MOUNTAINS.
TONIGHT...EXPECT THE ATMOSPHERE TO REMAIN STABLE FROM THE WET
MOUNTAINS AND TELLER COUNTY EASTWARD...AND OVER THE EASTERN
PLAINS. ANY CONVECTION WHICH MOVES INTO THIS REGION FROM THE WEST
SHOULD WEAKEN CONSIDERABLY. THROUGHOUT THE DAY...THE HRRR RUNS
HAVE TRENDED TOWARDS THE STRONGER STORMS STAYING FURTHER WEST OF
THE I25 CORRIDOR THIS EVENING. CANNOT RULE OUT A STRONG STORM
REACHING WALDO CANYON...BUT THE PROBABILITY IS LOW. HAVE TRIMMED
BACK POPS OVER THE EASTERN MOUNTAINS FROM EARLIER GRIDS AS STORMS
WILL WEAKEN. APPROACHING WEAK DISTURBANCE COULD ALLOW A FEW WEAK
STORMS TO MOVE EASTWARD ONTO THE I25 CORRIDOR. WITH WEAK UPSLOPE
CONTINUING OVERNIGHT...AREAS OF LOW CLOUDS COULD DEVELOP ALONG THE
EASTERN MOUNTAINS AND PORTIONS OF THE I25 CORRIDOR.
FRIDAY...THERE COULD BE MORE SUNSHINE TOMORROW OVER THE EASTERN
MOUNTAINS AND INTERSTATE 25 CORRIDOR AS SOME DRIER AIR ALOFT TRIES
TO MOVE SOUTHWARD AND THE UPSLOPE GRADIENT CONTINUES TO WEAKEN.
PRECIPITABLE WATERS COULD DECREASE BY THE AFTERNOON WITH THE DRIER
AIR ALOFT...ESPECIALLY OVER TELLER AND EL PASO COUNTIES.
HOWEVER...THERE WILL STILL BE ENOUGH MOISTURE FOR ANY STORMS TO
PRODUCE LOCALLY HEAVY RAINFALL...EVEN OVER TELLER COUNTY. LATEST
NAM STILL KEEPS PW OVER AN INCH ON THE PLAINS FROM ROUGHLY THE
ARKANSAS RIVER AND SOUTHWARD. KEPT LIKELY POPS FOR THE AFTERNOON
OVER THE EASTERN MOUNTAINS WITH INCREASED SUNSHINE. STILL APPEARS
TO BE CAPPED FURTHER EAST WITH ISOLATED POPS BY THE KANSAS BORDER.
OVER THE REMAINING MOUNTAINS...DRIER AIR ALOFT WILL MOSTLY STAY
NORTH OF THE CWA FOR ANOTHER DAY OF SCATTERED TO LIKELY AFTERNOON
STORMS. - -PGW--
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 229 PM MDT THU JUL 31 2014
NORTHERLY MID LEVEL FLOW WILL CONTINUE TO ADVECT DRIER AIR SOUTH
ACROSS THE AREA FRIDAY EVENING...PUSHING BEST CHANCE FOR
CONVECTION SOUTH INTO NM OVERNIGHT. WILL END POPS MOST AREAS LATE
FRI EVENING...KEEPING SOME LOW POPS PAST 06Z FOR A FEW STORMS
NEAR THE NM BORDER. FOR SAT...CENTER OF UPPER LEVEL HIGH PRESSURE
DRIFTS EASTWARD FROM UTAH INTO WRN CO...AND NORTHERLY FLOW AROUND
THE HIGH WILL KEEP SLIGHTLY DRIER AIR MASS IN PLACE OVER THE
EASTERN HALF OF THE AREA. STILL ENOUGH MOISTURE OVER THE MOUNTAINS
TO PRODUCE SCT AFTERNOON TSRA...WITH AN ISOLATED STORM OR TWO
ALONG THE I-25 CORRIDOR...ESPECIALLY FROM PUEBLO SOUTHWARD. MAX
TEMPS WILL FINALLY REBOUND BACK TOWARD AVERAGE LEVELS FOR EARLY
AUG...THOUGH EVEN WARMEST LOCATIONS ON THE PLAINS MAY NOT REACH
90F. HIGH THEN MOVES OVERHEAD SUN...WITH INCREASING MID LEVEL
MOISTURE OVER THE CONTINENTAL DIVIDE BY LATE AFTERNOON AS FLOW
BECOME SOUTHERLY ON THE BACK SIDE OF THE HIGH. THUS EXPECT AN
INCREASE IN TSRA COVERAGE OVER WESTERN MOUNTAINS AND
VALLEYS...WITH ISOLATED ACTIVITY FARTHER EAST. PLAINS...ESPECIALLY
EAST OF I-25 LOOK TO REMAIN DRY THROUGH SUN EVENING. MAXES SUN
CONTINUE TO CREEP UPWARD WITH HIGH OVERHEAD...AND A FEW 90S MAY
FINALLY REAPPEAR ON THE PLAINS.
UPPER LEVEL HIGH THEN DRIFTS SOUTH INTO EASTERN NM MON WHILE
FAIRLY DEEP TROUGH BEGINS TO TAKE SHAPE OVER THE GREAT BASIN. WITH
WESTERLY COMPONENT TO THE MID/UPPER FLOW DEVELOPING...SHOULD SEE
MOISTURE SPREAD EASTWARD ACROSS THE STATE WITH AN UPTURN IN PRECIP
CHANCES MOST LOCATIONS MON AFTERNOON/EVENING. UPPER TROUGH THEN
LIFTS NORTHEASTWARD OVER THE RIDGE TUE...PUSHING A COLD FRONT
SOUTH THROUGH THE PLAINS BY AFTERNOON. BEST COMBINATION OF DYNAMIC
LIFT AND MOISTURE APPEAR TO STAY OVER NRN CO TUE...WITH MORE ISOLATED
TO SCT CONVECTION FARTHER SOUTH...THOUGH UPSLOPE SURGE BEHIND THE
COLD FRONT COULD AID IN CONVECTION ALONG THE PALMER DIVIDE BY TUE
EVENING. DEEPENING UPSLOPE FLOW WILL LIKELY LEAD TO A RENEWED
CHANCE OF THUNDERSTORMS AND HEAVY RAIN POTENTIAL
WED/THU...ESPECIALLY OVER THE EASTERN MOUNTAINS AND PLAINS.
TEMPERATURES WILL REMAIN WARM MON/TUE MOST LOCATIONS...THEN
GRADUALLY COOL WED/THU AS UPPER HIGH RETREATS AND COOLER AIR
SPREADS SOUTH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1151 PM MDT THU JUL 31 2014
LOOKS LIKE THE CLOUD DECK SHOULD HOLD THROUGH MORNING...WHICH
SHOULD PREVENT FG OR BR FROM FORMING ALTHOUGH IT CANNOT
BE COMPLETELY RULED OUT DUE TO THE HIGH MOISTURE LEVELS
PRESENT. SOME SPOTTY SHOWERS ARE POSSIBLE THROUGH TOMORROW
MORNING...THEN THERE MAY BE A SECOND ROUND OF STRONGER SHOWERS
AND STORMS AFTER 20Z IN THE AFTERNOON. LATEST FORECAST GUIDANCE
SUGGESTS THE STRONGER STORMS WILL BE SOUTH OF HGWY 50...BUT
ISOLD- SCT STORMS WILL BE POSSIBLE AT THE TAF SITES AS WELL. ROSE
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ROSE
SHORT TERM...PGW
LONG TERM...PETERSEN
AVIATION...ROSE
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1123 PM MDT THU JUL 31 2014
.UPDATE...
ISSUED AT 935 PM MDT THU JUL 31 2014
THE HRRR MODEL HAS PICKED UP THE LINE OF THUNDERSTORMS THAT ARE
CURRENTLY CROSSING THE GREEN RIVER. NO OTHER MODEL HAVE SHOWED
THIS TREND...ALTHOUGH THE RAP KEPT THE AIR MASS UNSETTLED ACROSS
SW COLORADO THROUGH THE NIGHT INTO FRIDAY MORNING. THIS LINE IS
EXPECTED TO TRACK INTO SW COLORADO AFTER MIDNIGHT WITH SOME DECENT
QPF AMOUNTS BETWEEN A QUARTER /0.25/ TO ONE HALF /0.50/ INCH. WITH
THE AIR MASS STAYING RELATIVELY MOIST...THESE STORMS SHOULD BE
FAIRLY EFFICIENT RAIN PRODUCERS. FORECAST GRIDS HAVE BEEN UPDATED
TO REFLECT THE HRRR AND SHORT TERM TRENDS.
&&
.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 249 PM MDT THU JUL 31 2014
LOW STRATUS AND PATCHY MORNING FOG BURNED OFF BY 15Z THIS MORNING AS
SURFACE HEATING COMMENCED. THINKING FOG WAS A RESULT OF THE
SATURATED GROUND FROM RAIN YESTERDAY ALONG WITH COOLER OVERNIGHT
TEMPERATURES. STORMS WERE QUICK TO FIRE ONCE THIS LOW CLOUD DECK
CLEARED AROUND 17Z WITH STORMS STAYING CONFINED TO HIGHER TERRAIN
AND MORE NUMEROUS OVER THE SAN JUANS AS EXPECTED. THE EXCEPTION WAS
THE SOUTHERN COLORADO VALLEYS IN WHICH STORMS DRIFTED OFF THE SAN
JUANS JUST BEFORE 18Z. PRECIPITABLE WATER (PW) VALUES AROUND AN INCH
ON THE 12Z GJT SOUNDING THIS MORNING SO STILL PLENTY OF MOISTURE
AROUND TO GENERATE STORMS WITH SOME HEAVY RAIN POSSIBLE. BEST
ACTIVITY WILL BE SOUTH OF I-70 AS OPPOSED TO YESTERDAY WITH LESS
NORTH OF I-70 WHERE THERE IS LESS MOISTURE AND STORMS ARE EXPECTED
TO DRIFT INTO SOME VALLEY LOCATIONS BY MID AFTERNOON. SOME LOCALIZED
FLOODING IS POSSIBLE UNDER THE STRONGER STORMS WITH SOME SMALL HAIL
AND GUSTY OUTFLOW WINDS TO 40 MPH POSSIBLE. RECEIVED A REPORT OF A
MUDSLIDE ALONG HIGHWAY 133 NORTH OF MCCLURE PASS EARLY THIS
AFTERNOON OUT OF A STORM THAT DID NOT APPEAR THAT STRONG ON RADAR.
LOCALIZED MUDSLIDES AND DEBRIS FLOW ARE STILL POSSIBLE GIVEN THE
SATURATED GROUND FROM RECENT RAINS IN SOME OF THE STEEPER TERRAIN.
STORMS WILL LINGER THROUGH THE EVENING AND COME TO AN END BY
MIDNIGHT.
LESS MOISTURE IN PLACE ON FRIDAY AS THE HIGH PRESSURE RIDGE STARTS
SHIFTING WESTWARD BUT STILL ENOUGH TO GENERATE SHOWERS AND
THUNDERSTORMS DURING THE AFTERNOON AND EVENING HOURS WITH PW VALUES
AROUND 0.75 INCHES ON AVERAGE WITH HIGHER AMTS NEAR AN INCH TOWARDS
THE FOUR CORNERS. MUCH LESS MOISTURE EVIDENT ACROSS NE UTAH AND NW
COLORADO WITH 0.5 TO 0.75 INCHES. THE GFS INDICATES A DISTURBANCE
MOVING THROUGH THE NORTHWEST FLOW TOPPING THE RIDGE. THIS IS
INDICATED BY SOME VORT MAXES AND A 55 KT JET STREAK THAT MOVES
THROUGH. THE NAM IS NOT AS PRONOUNCED WITH THIS FEATURE BUT THIS
MAY ENHANCE ACTIVITY. DECIDED TO INCREASE POPS AS GIVEN THE
DISTURBANCE MOVING THROUGH AND REMAINING MOISTURE BEING RECYCLED
UNDER THE RIDGE...THIS WILL LEAD TO AN INCREASE IN STORM ACTIVITY
AND COVERAGE. LOOKS LIKE THE WESTERN COLORADO MOUNTAINS ARE FAVORED
IN THE AFTERNOON WITH STORMS DRIFTING OFF THE HIGHER TERRAIN INTO
VALLEYS LATER IN THE DAY. STORMS WILL HAVE DECENT MOTION WITH SOME
LOCALLY HEAVY RAINERS. STORMS SHOULD DIE DOWN AFTER SUNSET AS DRIER
AIR MOVES IN FRIDAY NIGHT WITH PW VALUES OF 0.5 TO THE NORTH AND
0.75 TO THE SOUTH.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 249 PM MDT THU JUL 31 2014
...HEAVY RAIN POTENTIAL INCREASES BEGINNING LATER SUNDAY...
SATURDAY...WITH THE RIDGE OF HIGH PRESSURE NEARLY OVERHEAD AND A
LIGHT NORTHWESTERLY FLOW ALOFT FURTHER DRYING IS EXPECTED. PW DROPS
TO AROUND 0.5 INCH ACROSS THE NORTH/0.8 INCH OVER THE FAR SOUTH WITH
NO SIGNIFICANT DISTURBANCE NOTED...THUS A GENERAL DOWN TURN IN
THUNDERSTORM ACTIVITY IS ANTICIPATED.
SUNDAY THROUGH TUESDAY...THE SUBTROPICAL RIDGE AXIS SLIDES BACK TO
THE PLAINS SUNDAY OPENING THE DOOR FOR ANOTHER SURGE OF DEEP
MONSOONAL MOISTURE FROM THE SOUTH. MODELS CONTINUE TO HINT AT
STRONGER WAVES FOR LATE SUNDAY INTO EARLY MONDAY AND AGAIN MONDAY
NIGHT INTO TUESDAY...WHICH WOULD HELP TO FOCUS CONVECTION AND LEAD
TO AN INCREASED THREAT FOR HEAVY RAINFALL.
WEDNESDAY THROUGH THURSDAY...A DRIER NORTHWEST FLOW IS INDICATED
BEHIND THE TUESDAY DISTURBANCE AS THE HIGH PRESSURE RIDGE REBUILDS
TO OUR WEST. DAILY THUNDERSTORMS ARE STILL EXPECTED BUT LESS WIDESPREAD
COMPARED TO EARLIER IN THE WEEK. TEMPERATURES ARE EXPECTED TO BE
AT SEASONAL TO SLIGHTLY BELOW SEASONAL LEVELS THROUGHOUT THE
EXTENDED PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1122 PM MDT THU JUL 31 2014
A FEW SHOWERS AND THUNDERSTORMS WILL PERSIST THROUGH THE NIGHT
ACROSS SOUTHWEST COLORADO. AFTER 17Z...SHOWERS AND THUNDERSTORMS
WILL EXPAND IN AREAL COVERAGE OVER THE HIGH TERRAIN AND SOUTHWEST
COLORADO. LOCALLY HEAVY SHOWERS MAY LOWER CIGS TO MVFR LEVELS OVER
THE MOUNTAINS. THE BEST THREAT FOR STORMS AND SHOWERS WILL BE
OVER SW COLORADO.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATE...PF
SHORT TERM...MDA
LONG TERM...TB
AVIATION...JDC
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
939 PM EDT SAT AUG 2 2014
.SYNOPSIS...
A FRONTAL BOUNDARY WILL REMAIN STALLED JUST OFF THE MID-ATLANTIC
COAST THROUGH THE REMAINDER OF THE WEEKEND. THIS REMNANTS OF THIS
BOUNDARY WILL DISSIPATE ALONG THE EASTERN SEABOARD EARLY NEXT WEEK
BEFORE A COLD FRONT MOVES THROUGH WEDNESDAY. HIGH PRESSURE BUILDS IN
FROM THE GREAT LAKES LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
ANOTHER WEAK LOW WILL AFFECT THE REGION TONIGHT INTO EARLY
SUNDAY. THE MODELS DIFFER WITH RESPECT TO THE SYSTEM WITH THE NAM
OFFERING GENEROUS QPF AND HIGH POPS EVERYWHERE...WHILE THE GFS IS
LIGHTER WITH THE QPF AND LESSER WITH THE POPS (MOSTLY CHC). THE EC
IS SHOWING COVERAGE LIKE THE NAM AND HIGHER QPF MORE LIKE THE GFS
(CLOSER TO THE COAST). WE HAVE LOWERED AND SLOWED THE TIMING OF THE POPS
ACROSS THE BOARD BASED ON THE LATEST RADAR TRENDS AND THE LATEST RAP
RUNS THE HRRR LOOKS A LITTLE TO WEST ON THE COVERAGE OF THE
PRECIPITATION. THE ONSET OF THE HIGHER POPS WERE ALSO SLOWED A BIT
BASED ON THE LATEST RAP AND RADAR TRENDS. SKY COVER WILL GRADUALLY
INCREASE TONIGHT SO LEFT MOSTLY SKIES IN TACT TEMPS MOSTLY
MAV/MET MIX WITH LOWS IN THE MID/UPPER 60S S/E AND UPPER 50S TO
LOW 60S N/W. THE TEMPERATURES AND DEWPOINTS WERE ADJUSTED SLIGHTLY
OVER THE NEXT FEW HOURS WERE ADJUSTED TO THE LATEST 01Z METAR OBS
AS WELL.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
SUNDAY MAY WELL END UP BEING LIKE SATURDAY...WITH A WEAK WAVE OF LOW
PRESSURE MOVING ALONG THE SHORE DURING THE FIRST PART OF THE
DAY...FOLLOWED BY SLOW IMPROVEMENT LATE. THE UPPER TROUGH TO THE
WEST WHICH WILL BE DIMINISHING...MAY STILL TRIGGER SOME SHOWERS N/W
DURING THE AFTERNOON. WE HAVE HIGHER POPS EARLY THEN DECREASING
THROUGH THE AFTERNOON. TEMPS WILL REMAIN BELOW NORMAL WITH MOSTLY
UPPER 70S/LOW 80S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
A MID-LVL SHORTWAVE TROUGH WILL LIFT NEWD THRU PA AND INTO NEW
ENGLAND SUNDAY NIGHT. A FEW SHOWERS AHEAD OF THIS SYSTEM MAY LINGER
INTO THE EARLY EVE BUT ACTIVITY SHOULD BE DIURNALLY DRIVEN...
DISSIPATING WITH THE LOSS OF SOLAR HEATING.
THE REMNANTS OF AN OLD SFC BOUNDARY THAT HAD STALLED NEAR THE
MID-ATLANTIC COAST OVER THE PAST FEW DAYS WILL REMAIN NEARBY EARLY
NEXT WEEK. HOWEVER, MODELS GENERALLY SHOW THE BOUNDARY BECOMING SO
DIFFUSE THAT IT IS DIFFICULT TO DISCERN WHERE THE ASSOCIATED LLVL
LIFT WOULD RESIDE. STILL EXPECT SOME SHOWERS TO INITIATE DURING THE
PEAK HEATING HOURS BOTH MONDAY AND TUESDAY OVER THE HIGHER TERRAIN,
BUT OPTED TO LOWER POPS TO AROUND 20 PERCENT AND MAINLY WEST OF I-95
(EXCEPT 30 PERCENT IN THE POCONOS) OWING TO A LACK OF ORGANIZED
LIFT. ENVIRONMENT MARGINALLY SUPPORTIVE OF THUNDERSTORM CHANCES BOTH
DAYS UNDER WEAK MID-LVL LAPSE RATES AND LIMITED INSTABILITY.
POSITIVELY-TILTED TROUGH WILL AMPLIFY UPSTREAM OVER GREAT LAKES/
MIDWEST/ERN CANADA TOWARD MIDWEEK. HEIGHT FALL AHEAD OF THIS TROUGH
WILL OCCUR IN CONJUNCTION WITH A STRENGTHENING COLD FRONT NEAR THE
EASTERN SEABOARD LATE TUESDAY NIGHT INTO WEDNESDAY. CHANCES FOR
SHOWERS AND STORMS AS THE FRONT PUSHES THRU.
12Z OPERATIONAL ECMWF/GFS/CANADIAN MODELS IN REASONABLE AGREEMENT
WITH THE COLD FRONT PROGRESSING SOUTH AND EAST OF THE AREA BY
THURSDAY. HIGH PRESSURE BUILDS IN FROM THE GREAT LAKES IN ITS
WAKE. THIS PATTERN FAVORS DRY CONDITIONS TO LATE IN THE WEEK.
TEMPS LOOK TO BE CLOSE TO CLIMO EARLY IN THE WEEK AND PERHAPS A
FEW DEGREES BELOW CLIMO MID TO LATE PART OF THE WEEK. MAX TEMPS
GENERALLY IN THE MU80S MON-TUE AND LM 80S WED-FRI.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
THE LOW PRESSURE SYSTEM THAT AFFECTED THE REGION EARLIER TODAY HAS
MOVED OFFSHORE. ABUNDANT LOW LEVEL MOISTURE REMAINS ACROSS THE
REGION...CONDITIONS AT KACY ARE STILL IFR...AND AT THE OTHER
END...VFR CONDITIONS ARE BEING OBSERVED AT KRDG AND KABE ALONG
WITH SOME PORTIONS OF THE DELAWARE VALLEY. ANOTHER WAVE WILL MOVE UP
ALONG THE COAST TONIGHT AND CIGS/VSBYS WILL DECREASE OR STAY AT
MVFR OVERNIGHT AND PERSIST INTO SUNDAY MORNING WITH SOME SHOWERS. THE
MAIN WINDOW FOR THE LOWEST CEILINGS WILL BE FROM 05Z-15Z WITH MVFR
MOST PREDOMINATE, SOME IFR CONDITIONS ARE LIKELY OVERNIGHT/ EARLY
SUNDAY MORNING FOR KMIV AND KACY. THERE IS A CHANCE FOR A BRIEF
PERIOD OF IFR CEILINGS JUST BEFORE SUNRISE FOR KPHL,KILG,KPNE,KTTN BUT
WITH LOWER CONFIDENCE OF THIS OCCURRING LEFT IT OUT OF THE 00Z TAFS.
WITH KRDG AND KABE BEING FURTHER AWAY FROM THE NEXT WAVE OF LOW
PRESSURE THEY WILL BE LEAST IMPACTED BY MVFR RESTRICTIONS
OVERNIGHT AND SUNDAY MORNING AND A SMALLER TIMEFRAME FOR MFVR
CEILINGS IS SHOWN.
OUTLOOK...
SUNDAY NIGHT THROUGH TUESDAY...A FEW SHRA AND PERHAPS AN ISO TSTM
DURING THE AFTN/EVE HRS EACH DAY, PRIMARILY WEST OF PHL AREA
TERMINALS. MAINLY VFR. LGT WINDS PREDOMINATELY OUT OF THE SOUTH.
TUESDAY NIGHT AND WEDNESDAY...CHANCE FOR SHRA/TSRA INCREASE AHEAD OF
A COLD FRONT. BRIEF FLIGHT RESTRICTIONS POSSIBLE IN HEAVIER
ACTIVITY. OTHERWISE VFR.
THURSDAY...VFR WITH HIPRES BUILDING IN.
&&
.MARINE...
THE PREVAILING WINDS ALONG THE NRN NJ COASTAL WATERS WERE 15 TO 20
KNOTS WITH SOME SCA GUSTS EARLIER. SEAS MOSTLY 4 - 5 FT. THE LATEST
OBS SHOW THE BEGINNINGS OF WHAT IS EXPECTED TO BE LIGHTER WINDS AND
DIMINISHING SEAS FOR THE OVERNIGHT PERIOD. WE WILL TAKE THE SCA FLAG
DOWN WITH THE 330 PM FORECAST. SCT SHOWERS INTO THE EARLY EVENING
THEN MORE SHOWERS MOVING FROM S TO N AROUND DAWN.
OUTLOOK...
SUNDAY NIGHT THROUGH THURSDAY...NO MARINE HEADLINES EXPECTED WITH
LIGHT WINDS. BEST CHANCES FOR THUNDERSTORMS IN THIS PERIOD WILL BE
WEDNESDAY.
&&
.RIP CURRENTS...
LONG PERIOD SWELLS FROM TROPICAL STORM BERTHA MAY AFFECT THE
COASTS OF DELAWARE AND NEW JERSEY PERHAPS AS EARLY AS LATE MONDAY.
AND CONTINUE TUESDAY INTO WEDNESDAY. THESE SWELLS WOULD BRING AN
ENHANCED THREAT FOR DANGEROUS RIP CURRENTS.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KLEIN
NEAR TERM...GAINES/O`HARA
SHORT TERM...O`HARA
LONG TERM...KLEIN
AVIATION...GAINES/KLEIN/O`HARA
MARINE...KLEIN/O`HARA
RIP CURRENTS...KLEIN
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
900 PM EDT SAT AUG 2 2014
.SYNOPSIS...
A FRONTAL BOUNDARY WILL REMAIN STALLED JUST OFF THE MID-ATLANTIC
COAST THROUGH THE REMAINDER OF THE WEEKEND. THIS REMNANTS OF THIS
BOUNDARY WILL DISSIPATE ALONG THE EASTERN SEABOARD EARLY NEXT WEEK
BEFORE A COLD FRONT MOVES THROUGH WEDNESDAY. HIGH PRESSURE BUILDS IN
FROM THE GREAT LAKES LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AN UPPER TROUGH REMAIN TO THE WEST OVER THE OHIO VALLEY WHILE A
FRONT/TROUGH REMAIN ALONG THE COASTAL AREAS. A WAVE MOVED ALONG THE
TROUGH THIS MORNING WHICH HELPED PRODUCE THIS MORNINGS SHOWERS
ACROSS THE REGION. WE ARE PRESENTLY BETWEEN SYSTEMS AS ANOTHER WEAK
LOW WILL AFFECT THE REGION TONIGHT INTO EARLY SUNDAY. THE MODELS
DIFFER WITH RESPECT TO THE SYSTEM WITH THE NAM OFFERING GENEROUS QPF
AND HIGH POPS EVERYWHERE...WHILE THE GFS IS LIGHTER WITH THE QPF AND
LESSER WITH THE POPS (MOSTLY CHC). THE EC IS SHOWING COVERAGE LIKE
THE NAM AND HIGHER QPF MORE LIKE THE GFS (CLOSER TO THE COAST). WE
HAVE MOSTLY CONTINUED WITH THE PREVIOUS FCST WITH HIGH POPS
(CATEGORICAL/LIKELY) FOR MOST OF THE ERN HALF OF THE REGION WITH
CHANCE POPS NORTH AND WEST. THE ONSET OF THE HIGHER POPS WERE SLOWED A
BIT BASED ON THE LATEST RAP AND RADAR TRENDS. SKY COVER WAS ALSO
ADJUSTED DOWNWARD FOR THE NEXT FEW HOURS NW OF PHL AS SOME BREAKS
ARE BECOMING MORE PREDOMINANT OVER THE LAST FEW HOURS. TEMPS
MOSTLY MAV/MET MIX WITH LOWS IN THE MID/UPPER 60S S/E AND UPPER
50S TO LOW 60S N/W.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
SUNDAY MAY WELL END UP BEING LIKE SATURDAY...WITH A WEAK WAVE OF LOW
PRESSURE MOVING ALONG THE SHORE DURING THE FIRST PART OF THE
DAY...FOLLOWED BY SLOW IMPROVEMENT LATE. THE UPPER TROUGH TO THE
WEST WHICH WILL BE DIMINISHING...MAY STILL TRIGGER SOME SHOWERS N/W
DURING THE AFTERNOON. WE HAVE HIGHER POPS EARLY THEN DECREASING
THROUGH THE AFTERNOON. TEMPS WILL REMAIN BELOW NORMAL WITH MOSTLY
UPPER 70S/LOW 80S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
A MID-LVL SHORTWAVE TROUGH WILL LIFT NEWD THRU PA AND INTO NEW
ENGLAND SUNDAY NIGHT. A FEW SHOWERS AHEAD OF THIS SYSTEM MAY LINGER
INTO THE EARLY EVE BUT ACTIVITY SHOULD BE DIURNALLY DRIVEN...
DISSIPATING WITH THE LOSS OF SOLAR HEATING.
THE REMNANTS OF AN OLD SFC BOUNDARY THAT HAD STALLED NEAR THE
MID-ATLANTIC COAST OVER THE PAST FEW DAYS WILL REMAIN NEARBY EARLY
NEXT WEEK. HOWEVER, MODELS GENERALLY SHOW THE BOUNDARY BECOMING SO
DIFFUSE THAT IT IS DIFFICULT TO DISCERN WHERE THE ASSOCIATED LLVL
LIFT WOULD RESIDE. STILL EXPECT SOME SHOWERS TO INITIATE DURING THE
PEAK HEATING HOURS BOTH MONDAY AND TUESDAY OVER THE HIGHER TERRAIN,
BUT OPTED TO LOWER POPS TO AROUND 20 PERCENT AND MAINLY WEST OF I-95
(EXCEPT 30 PERCENT IN THE POCONOS) OWING TO A LACK OF ORGANIZED
LIFT. ENVIRONMENT MARGINALLY SUPPORTIVE OF THUNDERSTORM CHANCES BOTH
DAYS UNDER WEAK MID-LVL LAPSE RATES AND LIMITED INSTABILITY.
POSITIVELY-TILTED TROUGH WILL AMPLIFY UPSTREAM OVER GREAT LAKES/
MIDWEST/ERN CANADA TOWARD MIDWEEK. HEIGHT FALL AHEAD OF THIS TROUGH
WILL OCCUR IN CONJUNCTION WITH A STRENGTHENING COLD FRONT NEAR THE
EASTERN SEABOARD LATE TUESDAY NIGHT INTO WEDNESDAY. CHANCES FOR
SHOWERS AND STORMS AS THE FRONT PUSHES THRU.
12Z OPERATIONAL ECMWF/GFS/CANADIAN MODELS IN REASONABLE AGREEMENT
WITH THE COLD FRONT PROGRESSING SOUTH AND EAST OF THE AREA BY
THURSDAY. HIGH PRESSURE BUILDS IN FROM THE GREAT LAKES IN ITS
WAKE. THIS PATTERN FAVORS DRY CONDITIONS TO LATE IN THE WEEK.
TEMPS LOOK TO BE CLOSE TO CLIMO EARLY IN THE WEEK AND PERHAPS A
FEW DEGREES BELOW CLIMO MID TO LATE PART OF THE WEEK. MAX TEMPS
GENERALLY IN THE MU80S MON-TUE AND LM 80S WED-FRI.
&&
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
THE LOW PRESSURE SYSTEM THAT AFFECTED THE REGION EARLIER TODAY HAS
MOVED OFFSHORE. ABUNDANT LOW LEVEL MOISTURE REMAINS ACROSS THE
REGION...CONDITIONS AT KACY ARE STILL IFR...AND AT THE OTHER
END...VFR CONDITIONS ARE BEING OBSERVED AT KRDG AND KABE ALONG
WITH SOME PORTIONS OF THE DELAWARE VALLEY. ANOTHER WAVE WILL MOVE UP
ALONG THE COAST TONIGHT AND CIGS/VSBYS WILL DECREASE OR STAY AT
MVFR OVERNIGHT AND PERSIST INTO SUNDAY MORNING WITH SOME SHOWERS. THE
MAIN WINDOW FOR THE LOWEST CEILINGS WILL BE FROM 05Z-15Z WITH MVFR
MOST PREDOMINATE, SOME IFR CONDITIONS ARE LIKELY OVERNIGHT/ EARLY
SUNDAY MORNING FOR KMIV AND KACY. THERE IS A CHANCE FOR A BRIEF
PERIOD OF IFR CEILINGS JUST BEFORE SUNRISE FOR KPHL,KILG,KPNE,KTTN BUT
WITH LOWER CONFIDENCE OF THIS OCCURRING LEFT IT OUT OF THE 00Z TAFS.
WITH KRDG AND KABE BEING FURTHER AWAY FROM THE NEXT WAVE OF LOW
PRESSURE THEY WILL BE LEAST IMPACTED BY MVFR RESTRICTIONS
OVERNIGHT AND SUNDAY MORNING AND A SMALLER TIMEFRAME FOR MFVR
CEILINGS IS SHOWN.
OUTLOOK...
SUNDAY NIGHT THROUGH TUESDAY...A FEW SHRA AND PERHAPS AN ISO TSTM
DURING THE AFTN/EVE HRS EACH DAY, PRIMARILY WEST OF PHL AREA
TERMINALS. MAINLY VFR. LGT WINDS PREDOMINATELY OUT OF THE SOUTH.
TUESDAY NIGHT AND WEDNESDAY...CHANCE FOR SHRA/TSRA INCREASE AHEAD OF
A COLD FRONT. BRIEF FLIGHT RESTRICTIONS POSSIBLE IN HEAVIER
ACTIVITY. OTHERWISE VFR.
THURSDAY...VFR WITH HIPRES BUILDING IN.
&&
.MARINE...
THE PREVAILING WINDS ALONG THE NRN NJ COASTAL WATERS WERE 15 TO 20
KNOTS WITH SOME SCA GUSTS EARLIER. SEAS MOSTLY 4 - 5 FT. THE LATEST
OBS SHOW THE BEGINNINGS OF WHAT IS EXPECTED TO BE LIGHTER WINDS AND
DIMINISHING SEAS FOR THE OVERNIGHT PERIOD. WE WILL TAKE THE SCA FLAG
DOWN WITH THE 330 PM FORECAST. SCT SHOWERS INTO THE EARLY EVENING
THEN MORE SHOWERS MOVING FROM S TO N AROUND DAWN.
OUTLOOK...
SUNDAY NIGHT THROUGH THURSDAY...NO MARINE HEADLINES EXPECTED WITH
LIGHT WINDS. BEST CHANCES FOR THUNDERSTORMS IN THIS PERIOD WILL BE
WEDNESDAY.
&&
.RIP CURRENTS...
LONG PERIOD SWELLS FROM TROPICAL STORM BERTHA MAY AFFECT THE
COASTS OF DELAWARE AND NEW JERSEY PERHAPS AS EARLY AS LATE MONDAY.
AND CONTINUE TUESDAY INTO WEDNESDAY. THESE SWELLS WOULD BRING AN
ENHANCED THREAT FOR DANGEROUS RIP CURRENTS.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KLEIN
NEAR TERM...GAINES/O`HARA
SHORT TERM...O`HARA
LONG TERM...KLEIN
AVIATION...GAINES/KLEIN/O`HARA
MARINE...KLEIN/O`HARA
RIP CURRENTS...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
216 PM EDT FRI AUG 1 2014
.SYNOPSIS...
SEVERAL WEAK SURFACE TROUGHS WILL MOVE INTO THE AREA TODAY, BEFORE
HIGH PRESSURE OVER THE WESTERN ATLANTIC PUSHES AN OFFSHORE WARM
FRONT NORTHWESTWARD ACROSS THE EAST COAST THIS WEEKEND. SEVERAL
DISTURBANCES WILL MOVE NORTHEAST ALONG THIS BOUNDARY THROUGH THE
WEEKEND. ANOTHER COLD FRONT WILL THEN MOVE ACROSS THE AREA LATE
TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WITH THE UPDATE, WE RAISED DEWPOINTS ACROSS THE REGION BY TWO TO
THREE DEGREES USING THE LAV/LAMP GUIDANCE TO REFLECT CURRENT OBS
AND TRENDS THROUGH LATE MORNING AND INTO THE AFTERNOON. NOT MUCH
ADJUSTMENT WAS NEEDED TO HOURLY TEMPS, AND TODAYS MAXIMUM TEMPS
LOOK ON TRACK, ESPECIALLY WITH THE INCOMING MID AND HIGH CLOUDS.
WE DID ADJUST POPS DOWN A BIT THROUGH THE REMAINDER OF THE
MORNING, BASED ON CURRENT RADAR TRENDS AND HRRR GUIDANCE AS
SHOWERS ARE HAVING A DIFFICULT TIME MAKING IT INTO OUR SOUTHERN
DELMARVA ZONES, WITH SOMEWHAT DRIER MID/UPPER LEVEL AIR. WE ALSO
CONFINED ANY ISOLATED TO SCATTERED TSTORM CHANCES TO THE
AFTERNOON.
OTHERWISE, AN ACTIVE WEATHER PATTERN WILL BE RAMPING UP IN THE
NEAR AND SHORT TERM. FIRST...A SHORT WAVE TROUGH CURRENTLY OVER
VIRGINIA WILL MOVE OVER THE REGION BY 18Z. THERE IS CURRENTLY AN
AREA OF MOSTLY STRATIFORM PRECIPITATION ASSOCIATED WITH THIS
TROUGH. HOWEVER...AS THIS TROUGH PROPAGATES NORTHEAST...IT WILL
ENCOUNTER DRIER AIR ESPECIALLY IN THE MID AND UPPER LEVELS.
THUS...EXPECT CLOUDS, BUT NOT NECESSARILY WIDESPREAD PRECIP TO
MOVE INTO THE REGION EARLY IN THE DAY. WHAT SHOWERS AND STORMS DO
MOVE INTO THE REGION SHOULD BE LIMITED IN COVERAGE, AT LEAST AT
FIRST. IT DOES APPEAR THAT THERE WILL BE ENOUGH INSTABILITY TO
SUPPORT THUNDERSTORMS. THE NAM EVEN SHOWS ML CAPE VALUES NEAR 1000
J/KG. HOWEVER, IT SEEMS THAT THE NAM IS OVERLY AGGRESSIVE WITH LOW
LEVEL MOISTURE RETURN, AND THUS TOO HIGH ON THE INSTABILITY. ALSO,
THE PERSISTENT CLOUD COVER SHOULD HELP TO KEEP SURFACE
TEMPERATURES DOWN SLIGHTLY, FURTHER LIMITING INSTABILITY. THUS,
THE GFS SEEMS TO HAVE A BETTER HANDLE ON THIS ASPECT, WITH ML CAPE
VALUES GENERALLY LESS THAN 500 J/KG.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
RIGHT ON THE HEALS OF THE FIRST SHORT WAVE TROUGH TODAY, A SECOND
UPPER LEVEL SHORT WAVE TROUGH APPROACHES THE REGION. THIS, COUPLED
WITH THE MOIST SOUTHERLY AND SOUTHWESTERLY FLOW, AND A SLOW MOVING
WARM FRONT WHICH APPROACHES THE REGION LATE TONIGHT, WILL MEAN
INCREASED PRECIP CHANCES FOR MUCH OF THE REGION. THIS IS ESPECIALLY
TRUE FOR THE EASTERN HALF OF THE REGION WHICH SHOULD HAVE SLIGHTLY
BETTER LIFT, AND SEE PRECIPITABLE WATER VALUES CLIMB TO NEAR 2
INCHES BY LATE IN THE PERIOD.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
OVERALL THE MEDIUM RANGE IS ON PAR WITH ONE ANOTHER WITH THE
SYNOPTIC FEATURES THROUGH EARLY NEXT WEEK. THE EARLY PART OF THE
LONGTERM PERIOD, THIS WEEKEND, IS STILL VIEWED AS AN AVERAGE TO
SLIGHTLY BELOW AVERAGE CONFIDENCE, INLAND, AS THE TIMING AND
PLACEMENT OF SEVERAL SMALLER IMPULSES AND COASTAL BAROCLINIC ZONE
INTERACTION OCCURS.
SATURDAY...STARTING TO SEE SOME BETTER CONSENSUS, THOUGH STILL NOT
GREAT, AND ACCORDING TO THE 01/00Z DATA THE NON-NCEP MEMBERS HAVE JUMPED
MORE TOWARDS THE NCEP GUIDANCE IN KEEPING THE BAROCLINIC ZONE AND
ITS SUBSEQUENT SURFACE WAVES MORE OFFSHORE...EC INCLUDED. THE GEFS
HAS BEEN PRETTY CONSISTENT THE PAST FEW NIGHTS WHILE THE EC
ENSEMBLES HAVE BEEN TRENDING LESS CONFIDENT IN THE MID-LEVELS AND AT
MORESO AT THE SURFACE. PWATS INCREASE UPWARDS 1.5 TO 1.75 INCHES BY
SATURDAY EVENING WITH GREATER AMOUNTS EAST OF THE DELAWARE RIVER.
UPPER LEVEL JET DYNAMICS WITH THE RIGHT ENTRANCE REGION SITTING
ACROSS THE MID-ATLANTIC AND AMPLE SUB-TROPICAL MOISTURE AVAILABLE
FOR THE PASSING WAVES TO TAP INTO, WE COULD BE LOOKING AT A HEAVY
RAIN POTENTIAL...GREATER CHANCES EAST OF THE RIVER CLOSER TO THE
COAST AND FRONTAL BOUNDARY. TEMPERATURES WILL STRUGGLE TO GET OUT OF
THE 70S IN A LOT OF PLACES WITH LOTS OF CLOUD COVER, RAIN, AND
EASTERLY FLOW. THE METMOS SEEMED TOO LOW, AS IT USUALLY GOES CRAZY
WITH STRATUS WHEN RAIN IS FORECASTED. ANY BREAKS IN THE CLOUDS FOR
AN HOUR OR TWO COULD EASILY BOOST SOME LOCATIONS INTO THE LOW-80S.
SUNDAY...THERE LOOKS TO BE A DRIER PERIOD, AT LEAST THE FIRST HALF
OF THE DAY BEFORE A STRONGER MID-LEVEL WAVE NEARS FROM THE WEST
DURING THE AFTERNOON HOURS...THIS IS THE KICKER VORT LOBE. COLD POOL
INTERACTION ALOFT AND MINIMAL SURFACE HEATING SHOULD BE ENOUGH FOR
SCATTERED SHOWERS WITH VERY ISOLATED CONVECTION. AGAIN, FRONTAL
BOUNDARY STILL CLOSE TO THE REGION SO WE HAVE LIKELY POPS ACROSS
SOUTHERN DELMARVA AND ALONG THE NJ COAST. TEMPERATURES MAY END UP
BEING A DEGREE OR TWO WARMER THAN SATURDAY WITH POSSIBLY MORE BREAKS
IN THE CLOUDS.
MONDAY...DEPENDING ON THE TIMING OF MORE MID-LEVEL SHORTWAVES, OR
LACK THEREOF, MONDAY COULD END UP BEING A MOSTLY DRY DAY. EC DOES
NOT SHOW MUCH FORCING WHILE THE GFS KEEPS A FEW IMPULSES SHEARING
THROUGH. GEFS PAINTS A PRETTY BROAD AREA OF AT LEAST CHANCE POPS AND
GIVEN THE UNCERTAINTY AT THIS POINT DID NOT WANT TO CHANGE TOO MUCH
DURING THE TIMEFRAME...CONTINUE CHANCE POPS WITH MODERATING
TEMPERATURES.
TUESDAY - THURSDAY...CONTINUING CYCLONIC FLOW ALOFT MAY BE ENOUGH
FOR ISOLATED SHOWER ACTIVITY EACH AFTERNOON, OTHERWISE A MOSTLY DRY
FORECAST IS EXPECTED THIS TIMEFRAME. WEAK FRONT MAY CROSS ON
WEDNESDAY WITH OUR BEST CHANCES AT SCATTERED ACTIVITY. TEMPERATURES
MODERATE EVEN MORE AND SHOULD END UP BEING NORMAL.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
WITH THE 18Z TAFS, WE HAVE INCLUDED A TEMPO GROUP FOR EITHER SHRA OR
TSRA COVERING THE AFTERNOON TO EARLY EVENING TIMEFRAME TO BEST
REFLECT THE POSSIBLE TIMING OF ISOLATED TO SCATTERED SHWRS/TSTORMS
ACROSS THE REGION. OVERALL, MOST CIGS/VSBYS WILL REMAIN VFR, BUT AN
ISOLATED SHWR/TSTORM COULD CAUSE LOCALLY REDUCED CIGS/VSBYS.
THEREAFTER, WE EXPECT A BIT OF A LULL IN ACTIVITY LATER IN THE
EVENING AS ISOLATED/SCATTERED CONVECTION WANES. ANOTHER DISTURBANCE
AND OFFSHORE FRONTAL BOUNDARY IS THEN EXPECTED TO BRING ANOTHER
ROUND OF RAIN/SHOWERS TO THE AREA DURING THE OVERNIGHT AND INTO
SATURDAY, GRADUALLY SPREADING FROM SOUTHEAST TO NORTHWEST AND MAINLY
IN THE 06Z TO 18Z SATURDAY TIMEFRAME. WITH THIS BATCH OF PRECIP, WE
DO EXPECT CONDITIONS TO LOWER TO MVFR, ESPECIALLY FOR KACY/KMIV AND
THE DELAWARE VALLEY TAF SITES, WITH SOMEWHAT LESS OF A CHANCE FOR
KABE/KRDG.
WITH REGARDS TO WINDS, SPEEDS ARE EXPECTED TO BE MAINLY UNDER 10
KNOTS THROUGH THE TAF PERIOD, WITH WINDS TURNING MORE FROM THE
SOUTHWEST TO THE SOUTHEAST WITH TIME THROUGH THIS EVENING. THE WINDS
WILL CONTINUE TO BACK MORE TOWARD AN EASTERLY TO NORTHEAST
DIRECTION DURING THE OVERNIGHT AND THROUGH SATURDAY, REMAINING
MOSTLY UNDER 10 KNOTS.
OUTLOOK...
SUNDAY...MOSTLY VFR WITH SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS POSSIBLE IN THE AFTERNOON. HEAVY RAIN MAY OCCUR CLOSER
TO THE COAST. MVFR/IFR CONDITIONS LIKELY IN SHOWERY ACTIVITY.
EASTERLY FLOW IN PLACE. MEDIUM CONFIDENCE.
MONDAY - TUESDAY...VFR. ISOLATED SHOWERS POSSIBLE ON EACH AFTERNOON.
MEDIUM CONFIDENCE.
&&
.MARINE...
EXPECT WINDS AND SEAS TO REMAIN BELOW SMALL CRAFT ADVISORY TODAY AND
TONIGHT WITH WINDS STAYING NEAR OR BELOW 20 KT AND SEAS BETWEEN 2
AND 3 FEET.
OUTLOOK...
FRIDAY - TUESDAY...SUB-SCA CONDITIONS ARE EXPECTED ACROSS OUR
WATERS THIS PERIOD.
&&
.RIP CURRENTS...
THE RISK OF RIP CURRENTS WILL INCREASE TO MODERATE TODAY AS THE
WINDS SHIFT TO SOUTHEASTERLY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...HEAVENER
NEAR TERM...JOHNSON/KLINE
SHORT TERM...JOHNSON
LONG TERM...HEAVENER
AVIATION...HEAVENER/KLINE
MARINE...HEAVENER/JOHNSON
RIP CURRENTS...JOHNSON
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1025 AM EDT FRI AUG 1 2014
.SYNOPSIS...
SEVERAL WEAK SURFACE TROUGHS WILL MOVE INTO THE AREA TODAY, BEFORE
HIGH PRESSURE OVER THE WESTERN ATLANTIC PUSHES AN OFFSHORE WARM
FRONT NORTHWESTWARD ACROSS THE EAST COAST THIS WEEKEND. SEVERAL
DISTURBANCES WILL MOVE NORTHEAST ALONG THIS BOUNDARY THROUGH THE
WEEKEND. ANOTHER COLD FRONT WILL THEN MOVE ACROSS THE AREA LATE
TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WITH THE UPDATE, WE RAISED DEWPOINTS ACROSS THE REGION BY TWO TO
THREE DEGREES USING THE LAV/LAMP GUIDANCE TO REFLECT CURRENT OBS
AND TRENDS THROUGH LATE MORNING AND INTO THE AFTERNOON. NOT MUCH
ADJUSTMENT WAS NEEDED TO HOURLY TEMPS, AND TODAYS MAXIMUM TEMPS
LOOK ON TRACK, ESPECIALLY WITH THE INCOMING MID AND HIGH CLOUDS.
WE DID ADJUST POPS DOWN A BIT THROUGH THE REMAINDER OF THE
MORNING, BASED ON CURRENT RADAR TRENDS AND HRRR GUIDANCE AS
SHOWERS ARE HAVING A DIFFICULT TIME MAKING IT INTO OUR SOUTHERN
DELMARVA ZONES, WITH SOMEWHAT DRIER MID/UPPER LEVEL AIR. WE ALSO
CONFINED ANY ISOLATED TO SCATTERED TSTORM CHANCES TO THE
AFTERNOON.
OTHERWISE, AN ACTIVE WEATHER PATTERN WILL BE RAMPING UP IN THE
NEAR AND SHORT TERM. FIRST...A SHORT WAVE TROUGH CURRENTLY OVER
VIRGINIA WILL MOVE OVER THE REGION BY 18Z. THERE IS CURRENTLY AN
AREA OF MOSTLY STRATIFORM PRECIPITATION ASSOCIATED WITH THIS
TROUGH. HOWEVER...AS THIS TROUGH PROPAGATES NORTHEAST...IT WILL
ENCOUNTER DRIER AIR ESPECIALLY IN THE MID AND UPPER LEVELS.
THUS...EXPECT CLOUDS, BUT NOT NECESSARILY WIDESPREAD PRECIP TO
MOVE INTO THE REGION EARLY IN THE DAY. WHAT SHOWERS AND STORMS DO
MOVE INTO THE REGION SHOULD BE LIMITED IN COVERAGE, AT LEAST AT
FIRST. IT DOES APPEAR THAT THERE WILL BE ENOUGH INSTABILITY TO
SUPPORT THUNDERSTORMS. THE NAM EVEN SHOWS ML CAPE VALUES NEAR 1000
J/KG. HOWEVER, IT SEEMS THAT THE NAM IS OVERLY AGGRESSIVE WITH LOW
LEVEL MOISTURE RETURN, AND THUS TOO HIGH ON THE INSTABILITY. ALSO,
THE PERSISTENT CLOUD COVER SHOULD HELP TO KEEP SURFACE
TEMPERATURES DOWN SLIGHTLY, FURTHER LIMITING INSTABILITY. THUS,
THE GFS SEEMS TO HAVE A BETTER HANDLE ON THIS ASPECT, WITH ML CAPE
VALUES GENERALLY LESS THAN 500 J/KG.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
RIGHT ON THE HEALS OF THE FIRST SHORT WAVE TROUGH TODAY, A SECOND
UPPER LEVEL SHORT WAVE TROUGH APPROACHES THE REGION. THIS, COUPLED
WITH THE MOIST SOUTHERLY AND SOUTHWESTERLY FLOW, AND A SLOW MOVING
WARM FRONT WHICH APPROACHES THE REGION LATE TONIGHT, WILL MEAN
INCREASED PRECIP CHANCES FOR MUCH OF THE REGION. THIS IS ESPECIALLY
TRUE FOR THE EASTERN HALF OF THE REGION WHICH SHOULD HAVE SLIGHTLY
BETTER LIFT, AND SEE PRECIPITABLE WATER VALUES CLIMB TO NEAR 2
INCHES BY LATE IN THE PERIOD.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
OVERALL THE MEDIUM RANGE IS ON PAR WITH ONE ANOTHER WITH THE
SYNOPTIC FEATURES THROUGH EARLY NEXT WEEK. THE EARLY PART OF THE
LONGTERM PERIOD, THIS WEEKEND, IS STILL VIEWED AS AN AVERAGE TO
SLIGHTLY BELOW AVERAGE CONFIDENCE, INLAND, AS THE TIMING AND
PLACEMENT OF SEVERAL SMALLER IMPULSES AND COASTAL BAROCLINIC ZONE
INTERACTION OCCURS.
SATURDAY...STARTING TO SEE SOME BETTER CONSENSUS, THOUGH STILL NOT
GREAT, AND ACCORDING TO THE 01/00Z DATA THE NON-NCEP MEMBERS HAVE JUMPED
MORE TOWARDS THE NCEP GUIDANCE IN KEEPING THE BAROCLINIC ZONE AND
ITS SUBSEQUENT SURFACE WAVES MORE OFFSHORE...EC INCLUDED. THE GEFS
HAS BEEN PRETTY CONSISTENT THE PAST FEW NIGHTS WHILE THE EC
ENSEMBLES HAVE BEEN TRENDING LESS CONFIDENT IN THE MID-LEVELS AND AT
MORESO AT THE SURFACE. PWATS INCREASE UPWARDS 1.5 TO 1.75 INCHES BY
SATURDAY EVENING WITH GREATER AMOUNTS EAST OF THE DELAWARE RIVER.
UPPER LEVEL JET DYNAMICS WITH THE RIGHT ENTRANCE REGION SITTING
ACROSS THE MID-ATLANTIC AND AMPLE SUB-TROPICAL MOISTURE AVAILABLE
FOR THE PASSING WAVES TO TAP INTO, WE COULD BE LOOKING AT A HEAVY
RAIN POTENTIAL...GREATER CHANCES EAST OF THE RIVER CLOSER TO THE
COAST AND FRONTAL BOUNDARY. TEMPERATURES WILL STRUGGLE TO GET OUT OF
THE 70S IN A LOT OF PLACES WITH LOTS OF CLOUD COVER, RAIN, AND
EASTERLY FLOW. THE METMOS SEEMED TOO LOW, AS IT USUALLY GOES CRAZY
WITH STRATUS WHEN RAIN IS FORECASTED. ANY BREAKS IN THE CLOUDS FOR
AN HOUR OR TWO COULD EASILY BOOST SOME LOCATIONS INTO THE LOW-80S.
SUNDAY...THERE LOOKS TO BE A DRIER PERIOD, AT LEAST THE FIRST HALF
OF THE DAY BEFORE A STRONGER MID-LEVEL WAVE NEARS FROM THE WEST
DURING THE AFTERNOON HOURS...THIS IS THE KICKER VORT LOBE. COLD POOL
INTERACTION ALOFT AND MINIMAL SURFACE HEATING SHOULD BE ENOUGH FOR
SCATTERED SHOWERS WITH VERY ISOLATED CONVECTION. AGAIN, FRONTAL
BOUNDARY STILL CLOSE TO THE REGION SO WE HAVE LIKELY POPS ACROSS
SOUTHERN DELMARVA AND ALONG THE NJ COAST. TEMPERATURES MAY END UP
BEING A DEGREE OR TWO WARMER THAN SATURDAY WITH POSSIBLY MORE BREAKS
IN THE CLOUDS.
MONDAY...DEPENDING ON THE TIMING OF MORE MID-LEVEL SHORTWAVES, OR
LACK THEREOF, MONDAY COULD END UP BEING A MOSTLY DRY DAY. EC DOES
NOT SHOW MUCH FORCING WHILE THE GFS KEEPS A FEW IMPULSES SHEARING
THROUGH. GEFS PAINTS A PRETTY BROAD AREA OF AT LEAST CHANCE POPS AND
GIVEN THE UNCERTAINTY AT THIS POINT DID NOT WANT TO CHANGE TOO MUCH
DURING THE TIMEFRAME...CONTINUE CHANCE POPS WITH MODERATING
TEMPERATURES.
TUESDAY - THURSDAY...CONTINUING CYCLONIC FLOW ALOFT MAY BE ENOUGH
FOR ISOLATED SHOWER ACTIVITY EACH AFTERNOON, OTHERWISE A MOSTLY DRY
FORECAST IS EXPECTED THIS TIMEFRAME. WEAK FRONT MAY CROSS ON
WEDNESDAY WITH OUR BEST CHANCES AT SCATTERED ACTIVITY. TEMPERATURES
MODERATE EVEN MORE AND SHOULD END UP BEING NORMAL.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
MOSTLY VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD;
ALTHOUGH, SOME MVFR CIGS ARE STILL LINGERING FOR OUR WESTERN TAF
SITES, NAMELY KABE AND KRDG. THIS SHOULD IMPROVE TO VFR CIGS FOR
THESE SITES BY AROUND 16Z. THE BIGGER QUESTION FOR TODAY WILL BE
TIMING OF SHRA AND TSRA. VERY LOW CONFIDENCE ON THE TIMING OF ANY
SHRA AND TSRA THROUGH THE DAY TODAY, BUT IF ANY DO MOVE OVER
TERMINALS THROUGH THE DAY, EXPECT VFR CONDITIONS EVEN WITH THE
PRECIPITATION. COVERAGE THROUGH 00Z IS EXPECTED TO BE TOO LIMITED
TO INCLUDE IN THE TAFS AT THIS TIME. AFTER 00Z...CHANCE FOR SHRA
INCREASES. THERE MAY REMAIN ISOLATED TSRA AFTER SUNSET, BUT EXPECT
THE RISK FOR LIGHTNING TO DECREASE BY LATE EVENING, AND AT THIS
TIME WE HAVE KEPT ANY MENTION OF TSRA OUT OF THE TAFS AS ANY
OCCURENCE LOOKS TO BE ISOLATED. FOR THE PERIOD BETWEEN 00 AND
12Z, EXPECT SHRA TO BE MORE WIDESPREAD ESPECIALLY FOR LOCATIONS
ALONG AND EAST OF THE DELAWARE RIVER, INCLUDING KPHL, KPNE, KTTN,
KILG, KMIV, AND KACY. MVFR VISIBILITIES WILL BE POSSIBLE WITH ANY
OVERNIGHT SHRA.
OUTLOOK...
SATURDAY - SUNDAY...MOSTLY VFR WITH SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS POSSIBLE EACH AFTERNOON. HEAVY RAIN MAY OCCUR CLOSER
TO THE COAST. MVFR/IFR CONDITIONS LIKELY IN SHOWERY ACTIVITY.
EASTERLY FLOW IN PLACE. MEDIUM CONFIDENCE.
MONDAY - TUESDAY...VFR. ISOLATED SHOWERS POSSIBLE ON EACH AFTERNOON.
MEDIUM CONFIDENCE.
&&
.MARINE...
EXPECT WINDS AND SEAS TO REMAIN BELOW SMALL CRAFT ADVISORY TODAY AND
TONIGHT WITH WINDS STAYING NEAR OR BELOW 20 KT AND SEAS BETWEEN 2
AND 3 FEET.
OUTLOOK...
FRIDAY - TUESDAY...SUB-SCA CONDITIONS ARE EXPECTED ACROSS OUR
WATERS THIS PERIOD.
&&
.RIP CURRENTS...
THE RISK OF RIP CURRENTS WILL INCREASE TO MODERATE TODAY AS THE
WINDS SHIFT TO SOUTHEASTERLY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...HEAVENER
NEAR TERM...JOHNSON/KLINE
SHORT TERM...JOHNSON
LONG TERM...HEAVENER
AVIATION...HEAVENER/JOHNSON/KLINE
MARINE...HEAVENER/JOHNSON
RIP CURRENTS...JOHNSON
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
211 PM EDT FRI AUG 1 2014
.NEAR TERM /THROUGH TONIGHT/...
PERSISTENT SURFACE LOW IS CENTERED ALONG THE FL/GA LINE NEAR THE
OKEFENOKEE SWAMP...WITH ASSOCIATED TROUGH EXTENDING NE ALONG THE
GA/SC COAST WHERE IT`S BEEN STUCK FOR A COUPLE DAYS. A LONGWAVE
TROUGH COVERS A LARGE PORTION OF THE U.S. FROM A STACKED LOW OVER
ONTARIO SWD OVER THE GREAT LAKES INTO THE CENTRAL GULF OF MEXICO.
THE TROUGH IS PROVIDING A DEEP SWLY FLOW WHICH IS PUSHING COPIOUS
TROPICAL MOISTURE OVER OUR REGION. SCATTERED SHOWERS/STORMS HAVE
ERUPTED OVER SE GA AS ISENTROPIC LIFT INCREASES NORTH OF THE SFC
TROUGH...AND HAVE HIGH CHANCE POPS INTO THE EVENING HOURS. AT 18Z
THE SEA BREEZE IS PINNED ALONG THE COAST...BUT AS IT DRIFTS INLAND
LATER THIS AFTN...CONVECTION WILL FIRE ALONG THE SBRZ AND ST.
JOHNS RIVER BREEZE. THE HRRR ONLY SHOWS ISOLATED ACTIVITY ACROSS
MOST OF NE FL WITH HIGHER COVERAGE NEAR THE OCALA NAT`L FOREST.
WILL KEEP LOW CHANCE POPS BETWEEN HWY 301 AND I-95 LATER THIS
AFTN. CONVECTION WILL FADE DURING THE EVENING AND THEN INCREASE
AGAIN OVER THE COASTAL WATERS LATE TONIGHT. SOME OF THESE SHOWERS
CAN BE EXPECTED TO SLIDE ONSHORE GIVING BRIEF DOWNPOURS TO A FEW
BEACH LOCATIONS.
.SHORT TERM /SATURDAY THROUGH MONDAY/...
UPPER LEVEL TROUGHING WILL RESIDE JUST TO THE NORTHWEST OF THE
REGION INTO EARLY NEXT WEEK...WITH AN INVERTED TROUGH AT THE LOWER
LEVELS. THE RESULT WILL BE ABOVE NORMAL PRECIP CHANCES WITH HIGH
END CHANCE TO LIKELY POPS EACH AFTERNOON INTO EARLY EVENING.
SHWRS/TSTMS WILL DIMINISH LATE EVENING THROUGH EARLY MORNING AS
INSTABILITY DECREASES. WITH INCREASING DEEP LAYER SHEAR IN CLOSE
PROXIMITY TO THE UPPER TROUGH...A FEW STORMS COULD BECOME STRONG.
EXPECT TEMPERATURES TO REMAIN WITHIN A DEGREE OR TWO OF NORMAL.
.LONG TERM /TUESDAY THROUGH FRIDAY/...
TS BERTHA IS EXPECTED TO RECURVE TO THE N/NE BY MIDWEEK AS TROUGHING
REMAINS IN PLACE ACROSS THE EASTERN CONUS. ANY IMPACTS TO THE AREA
WILL BE MINIMAL IF ANY...WITH SOME POSSIBILITY OF ELEVATED RIP
CURRENTS. MEDIUM RANGE MODELS CONTINUE TO SHOW THE UPPER TROUGH
MOVING BACK TO THE NORTH WITH ZONAL FLOW TO LOW AMPLITUDE RIDGING
DEVELOPING ACROSS THE FL PENINSULA FOR THE MIDDLE/LATTER PORTIONS OF
NEXT WEEK. PRECIP COVERAGE WILL DECREASE...WITH MAINLY LOW END
CHANCES OF AFTN SHWRS/TSTMS. NEAR NORMAL TEMPERATURES WILL CONTINUE.
.AVIATION...
VFR EXPECTED AT NE FL TERMINALS AND WITH SHOWERS ALREADY
DEVELOPING OVER SE GA...HAVE MVFR CONDS AT SSI THIS AFTERNOON.
SCATTERED STORMS WILL DEVELOP AND HAVE VCTS UNTIL 00Z-02Z. LOW
STRATUS AND/OR FOG ARE POSSIBLE LATE TONIGHT...BUT CONFIDENCE IS
TOO LOW TO INCLUDE FOR NOW.
&&
.MARINE...
SURFACE TROUGH DIVIDES THE FL AND GA WATERS WITH S-SE FLOW ACROSS
FL WATERS AND N-NE FLOW OVER GA WATERS. THE TROUGH IS FORECAST TO
DRIFT WEST ALLOWING FOR ONSHORE FLOW TO DEVELOP THROUGH THE
WEEKEND. A TROUGH IS EXPECTED TO RE-DEVELOP ALONG THE EAST COAST
EARLY NEXT WEEK.
RIP CURRENTS: LOW TO MODERATE RISK IS EXPECTED OVER THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 74 92 74 91 / 50 60 40 60
SSI 77 87 77 85 / 30 50 30 60
JAX 75 90 75 89 / 30 60 30 60
SGJ 75 88 75 89 / 20 50 30 60
GNV 72 92 72 91 / 20 60 40 60
OCF 72 92 72 91 / 20 60 40 60
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
TRABERT/ALLEN
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
1004 AM EDT Fri Aug 1 2014
.Near Term [Through Today]...
13Z MSAS and RAP objective analysis indicated a subtle surface
ridge extending from the Piedmont of North Carolina southwest to
central Georgia. Northeasterly low-level flow was associated with
this over much of the same region, and this coincided with an
area of stratus extending as far southwest as our Georgia
counties more reminiscent of autumn. This stratus should scatter
out later this morning, but there should be a weak convergence
zone and thetae gradient somewhere in the vicinity of the current
edge of the cloud shield by 18-20Z. Convection-allowing models are
consistent in developing isolated-scattered showers and storms in
our Georgia zones this afternoon. This is where we have focused
our >20% PoPs today. To the west and south - in southeast Alabama
and our Florida zones - boundary layer average mixing ratios are
considerably lower, indicating that dewpoints are likely to mix
out into the low-mid 60s this afternoon. The drier low level air
should inhibit most convective development, so we have indicated a
mainly dry forecast in these areas. High temperatures should be in
the low-mid 90s for the most part, although we tweaked the highs
down slightly in the northeast part of our Georgia counties where
cloud cover may hang on later into the day.
&&
.Prev Discussion [342 AM EDT]...
.Short Term [Tonight Through Sunday]...
A combination of upper level support from an eastern U.S.
mid/upper trough will combine with a weak front, and disturbed
sea breeze circulations to yield near, to slightly above average
rain chances through the weekend. Afternoon highs will be near
average (lower 90s) each afternoon, with overnight lows in the
lower 70s.
.Long Term [Sunday Night Through Friday]...
The aforementioned positive-tilt 500 mb trough will continue to
stretch from TN to the Northwest Gulf of Mexico, bringing moist
southwest flow aloft over our forecast area through Tuesday. This,
along with aforementioned remnant frontal system across our
region will contribute to above-climo rain chances (50-60% PoPs).
By Wednesday and Thursday, however, a deep layer ridge will build
across the Gulf of Mexico and Gulf Coast, reducing (somewhat) the
deep layer moisture and synoptic scale forcing. This will mark a
return to a more typical late summertime pattern, with near-climo
PoPs (30-40%) and thunderstorms driven primarily by the sea/land
breeze circulation and other mesoscale boundaries. Temperatures
will be near climatology, with highs in the lower to mid 90s and
lows in the 70s.
.Aviation...
[Through 12Z Saturday]
VFR conditions are expected to prevail through the TAF period but
there is a chance of VCTS at ABY, and VLD late this afternoon.
There are no major CIGS/VIS concerns but any terminals that receive
TS could briefly drop down to MVFR/IFR.
.Marine...
Low wind and sea conditions will prevail for the next several days
under a weak surface pressure pattern.
.Fire Weather...
Summer-like conditions and increasing rain chances will result in no
fire weather concerns over the next few days.
.Hydrology...
With our area rivers below bank full stage and seasonable rainfall
totals in the forecast, no flooding is expected through the next
week.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 95 71 93 72 92 / 10 10 50 20 50
Panama City 89 75 89 75 88 / 10 10 40 30 40
Dothan 93 71 91 71 90 / 20 10 40 20 60
Albany 91 71 91 72 90 / 40 30 40 20 50
Valdosta 96 70 95 71 95 / 20 20 50 30 60
Cross City 92 69 93 71 92 / 10 10 30 30 40
Apalachicola 89 72 88 74 89 / 10 10 30 30 30
&&
.TAE Watches/Warnings/Advisories...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...LAMERS
SHORT TERM...HARRIGAN
LONG TERM...FOURNIER
AVIATION...GOULD/DOBBS
MARINE...HARRIGAN
FIRE WEATHER...GOULD/DOBBS
HYDROLOGY...MOORE
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
123 AM EDT FRI AUG 1 2014
.SYNOPSIS...
A TROUGH OF LOW PRESSURE WILL LINGER NEAR THE SOUTHEAST COAST THROUGH
THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
00Z MODEL GUIDANCE CONTINUES TO INDICATE POTENTIAL FOR NOCTURNAL
CONVECTIVE RAINS ALONG THE CENTRAL SOUTH CAROLINA COASTAL AREA
WHERE LOW AND DEEP LAYERED MOISTURE CONVERGENCE REMAINS SIGNIFICANT.
MINOR ADJUSTMENTS TO THE FORECAST ON THE MIDNIGHT UPDATE...SKY COVER
IN SE GEORGIA AND SOME WINDS WITH THE CURRENT POSITION OF THE
COASTAL SURFACE TROUGH.
WATER VAPOR IMAGERY SHOWS A PRONOUNCED IMPULSE MOVE ACROSS ALABAMA
AND GEORGIA EARLY THIS EVENING WHICH IS PROGGED TO APPROACH THE
AREA FROM THE SOUTHWEST OVERNIGHT. SHOWERS/TSTMS ARE ALREADY
REDEVELOPING OVER CENTRAL AND WESTERN GEORGIA AHEAD OF THIS
FEATURE WITHIN A CORRIDOR OF ENHANCED UVM. THE LATEST SET OF
MESOSCALE MODELS INCLUDING THE RAP AND 4KM-WRF SUGGEST ADDITIONAL
SHOWERS/TSTMS WILL REDEVELOP OVER THE ATLANTIC AND MOVE INLAND
WELL AFTER MIDNIGHT. IT APPEARS SEVERAL ENHANCED CONFLUENCE ZONES
WILL SETUP OFF THE GEORGIA COAST IN THE VICINITY OF THE COASTAL
TROUGH WITH MEAN STEERING TRAJECTORIES FAVORING THE LOWER SOUTH
CAROLINA COAST AS 850-700 HPA WINDS VEER WITH TIME. PWATS SURGING
BACK NEAR 2 INCHES...ENHANCED UVM ASSOCIATED WITH THE APPROACHING
SHORTWAVE AND FAVORABLE WIND PROFILES ATOP THE HYBRID WEDGE
SUGGEST THERE WILL BE A CONTINUE RISK FOR HEAVY RAINFALL OVERNIGHT
INTO FRIDAY MORNING. ADJUSTED POPS UP PER GOING SHORT TERM AND
MODEL TRENDS...SHOWING CATEGORICAL POPS ACROSS THE FAR NORTH
THROUGH ABOUT 11 PM WITH 30-50 PERCENT POPS AFTER MIDNIGHT--HIGHEST
ALONG THE LOWER SOUTH CAROLINA COAST.
AS MUCH AS 4-8 INCHES OF RAIN HAS FALLEN OVER PORTIONS OF
CHARLESTON...BERKELEY...DORCHESTER AND COLLETON COUNTIES OVER THE
PAST 12 HOURS...MOST OF WHICH HAS FALLEN WITH THE LAST 6 HOURS.
WITH THE RISK FOR ADDITIONAL HEAVY RAIN AND FLOODING POSSIBLE
OVERNIGHT INTO FRIDAY MORNING...A PRECAUTIONARY FLASH FLOOD WATCH
WAS ISSUED FOR THE AFOREMENTIONED COUNTIES UNTIL LATE FRIDAY
MORNING.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY/...
FRIDAY AND FRIDAY NIGHT...A DEEP SOUTHWEST FLOW ALOFT WILL PREVAIL
ACROSS THE REGION BETWEEN AN UPPER TROUGH EXTENDING FROM THE GREAT
LAKES REGION THROUGH THE MIDDLE/LOWER MISSISSIPPI VALLEY AND A
STRONG UPPER RIDGE OVER THE WESTERN ATLANTIC. THIS WILL PUSH
PRECIPITABLE WATER VALUES UPWARDS OF 1.9 INCHES ACROSS THE AREA. AT
THE SURFACE...A WELL-DEFINED COASTAL TROUGH APPEARS TO SHIFT JUST
INLAND DURING THE DAY WHERE IT WILL LINGER THROUGH FRIDAY NIGHT. THE
DEEP MOISTURE COMBINED WITH CONVERGENCE ALONG/NEAR THE SURFACE
TROUGH WILL CAUSE SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS TO
DEVELOP. IT APPEARS THE GREATEST COVERAGE WILL BE OFFSHORE EXTENDING
NORTHWARD INTO NORTH CAROLINA...AND ALSO JUST INLAND FROM THE COAST
ALONG THE WESTERN PERIPHERY OF THE TROUGH. GIVEN WEAK STORM MOTIONS
HAVE ADDED HEAVY RAINFALL TO THE FORECAST AS LOCALIZED FLOODING WILL
BE POSSIBLE. EXTENSIVE CLOUD COVER AND ONSHORE FLOW WILL LIMIT HIGHS
TO THE UPPER 80S TO AROUND 90 ACROSS MUCH OF THE AREA INLAND FROM
THE COAST. LOWS FRIDAY NIGHT SHOULD BE IN THE LOWER TO MID 70S.
SATURDAY THROUGH SUNDAY...UNSETTLED CONDITIONS WILL CONTINUE THROUGH
THE WEEKEND. THE UPPER TROUGH TO THE WEST WILL AMPLIFY WHILE STRONG
RIDGING PERSISTS OVER THE WESTERN ATLANTIC. MEANWHILE...A TROUGH OF
LOW PRESSURE AT THE SURFACE WILL LINGER NEAR OR JUST INLAND OF THE
COAST. DEEP SOUTHWEST FLOW ALOFT WILL CONTINUE TO CAUSE PRECIPITABLE
WATER VALUES TO RISE...LIKELY EXCEEDING 2 INCHES ACROSS MOST OF THE
REGION. THE ABUNDANT MOISTURE...CONVERGENCE NEAR THE TROUGH AND
SEVERAL DISTURBANCES PASSING IN THE SOUTHWEST FLOW ALOFT WILL RESULT
IN SHOWERS AND THUNDERSTORMS BECOMING LIKELY ACROSS MOST OF THE
AREA. THE THREAT FOR HEAVY RAINFALL AND LOCALIZED FLOODING WILL
CONTINUE AS WELL. TEMPERATURES WILL BE IMPACTED BY EXTENSIVE
CLOUDINESS AND GOOD COVERAGE OF SHOWERS/THUNDERSTORMS...THUS DO NOT
ANTICIPATE HIGHS EXCEEDING THE UPPER 80S. LOWS SATURDAY NIGHT SHOULD
BE IN THE LOWER TO MID 70S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THANKS TO THE PRESENCE OF THE LINGERING DEEP TROUGH ALOFT AND DEEP
MOISTURE ACROSS THE AREA...THE ACTIVE PERIOD OF WEATHER WILL
CONTINUE INTO EARLY NEXT WEEK. THE SURFACE TROUGH IN THE AREA
FINALLY BEGINS TO WEAKEN TUESDAY INTO WEDNESDAY WHILE ATLANTIC
RIDGING BEGINS TO PUSH BACK IN FROM THE EAST. BY THE MIDDLE OF THE
WEEK IT APPEARS THAT WE WILL RETURN TO A MUCH MORE TYPICAL DIURNAL
PATTERN OF SHOWERS AND THUNDERSTORMS. ALSO...TEMPERATURES WILL WARM
BACK TO NEAR NORMAL VALUES LATE IN THE PERIOD.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
KCHS...SHOWERS AND POSSIBLY SOME THUNDERSTORMS ARE EXPECTED TO
ADVECT ONSHORE AND IMPACT THE TERMINAL BEGINNING NEARING DAYBREAK
IF NOT SOONER. IN ADDITION...GIVEN THE EARLIER HEAVY RAINFALL
THAT OCCURRED...SOME PATCHY GROUND FOG AND LOW STRATUS COULD
DEVELOP AND RESULT IN FLIGHT RESTRICTIONS. IFR CIGS LURK JUST OFF
THE WEST IN SATURATED LOW LEVEL AIR AT 0530Z. AS A RESULT...THE
TAF INDICATES TEMPO SHOWERS WITH MVFR CONDITIONS IN THE 10-14Z
TIME FRAME. THEN VFR CONDITIONS SHOULD PREVAIL...ALTHOUGH SHOWERS
WITH AT LEAST SOME THUNDERSTORMS IN THE VICINITY COULD BE AN ISSUE
THROUGH ABOUT 20Z WITH ANY FLIGHT RESTRICTIONS BEING TEMPORARY
DURING TIMES OF HEAVIER RAINFALL. THE SHOWERS/THUNDERSTORMS SHOULD
SHIFT WEST OF THE TERMINAL LATER IN THE AFTERNOON AS A COASTAL
TROUGH MOVES INLAND.
KSAV...VFR CONDITIONS ARE GENERALLY EXPECTED TO PREVAIL AT THE
TERMINAL THROUGH 06Z SATURDAY. HOWEVER...PATCHY GROUND FOG OR EVEN
SOME LOW CLOUDS COULD RESULT IN TEMPORARY FLIGHT RESTRICTIONS TO
MVFR/IFR LEVELS IN THE 09-13Z TIME FRAME. SCATTERED SHOWERS AND
THUNDERSTORMS ARE EXPECTED THIS AFTERNOON...BUT GIVEN LOWER
CONFIDENCE IN TIMING/COVERAGE HAVE LEFT MENTION OUT OF THE
FORECAST AT THIS TIME.
EXTENDED AVIATION...A SURFACE TROUGH WILL LINGER THROUGH EARLY NEXT
WEEK. AN UNSETTLED PERIOD IS EXPECTED AND THERE ARE INCREASING
CHANCES FOR PERIODIC FLIGHT RESTRICTIONS DUE TO SHOWERS AND
THUNDERSTORMS DURING THIS TIME.
&&
.MARINE...
ACROSS SC WATERS...A GRADIENT ENHANCED BETWEEN LOW PRESSURE TO THE
SOUTH AND HIGH PRESSURE TO THE NORTH WILL SUPPORT ELEVATED ONSHORE
WINDS OF 15-20 KT THIS EVENING...THEN THE GRADIENT AND ASSOCIATED
WINDS COULD RELAX SOMEWHAT OVERNIGHT. ACROSS GA WATERS...A WEAKER
GRADIENT CLOSER TO LOW PRESSURE WILL SUPPORT S/SE WINDS MAINLY 15
KT OR LESS. SEAS WILL RANGE FROM 2-4 FT ACROSS THE WATERS THROUGH
TONIGHT.
FRIDAY THROUGH MONDAY...A TROUGH OF LOW PRESSURE WILL LINGER NEAR OR
JUST INLAND OF THE COAST THROUGH EARLY NEXT WEEK. WINDS WILL
GENERALLY REMAIN ANYWHERE FROM EAST TO SOUTH ACROSS THE WATERS
DURING THIS TIME. WHILE THE GRADIENT MAY TIGHTEN AT TIMES AND ALLOW
FOR MODEST WIND INCREASES...OVERALL WINDS AND SEAS ARE EXPECTED TO
REMAIN BELOW ADVISORY THRESHOLDS.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...FLASH FLOOD WATCH UNTIL 11 AM EDT THIS MORNING FOR SCZ043>045-
049-050-052.
MARINE...NONE.
&&
$$
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...
AREA FORECAST DISCUSSION...CORRECTED AVIATION DISCUSSION
NWS QUAD CITIES IA IL
1138 PM CDT THU JUL 31 2014
.UPDATE...
ISSUED AT 1137 PM CDT THU JUL 31 2014
A SHORTWAVE AROUND 700 MB IN THE CYCLONIC NW FLOW CURRENTLY
MOVING THROUGH SW IA MAY TRIGGER ADDITIONAL ISOLATED SHOWERS OVER
SOUTHEAST IA...NE MO INTO W CENTRAL IL LATER TONIGHT AND WILL
KEEP SLIGHT CHANCE WORDING GOING. WHILE THE POTENTIAL FOR
THUNDERSTORMS IS NOT ZERO...MARGINAL MID LEVEL LAPSE RATES WILL
SUPPORT PRIMARILY WEAK SHOWERS AND WILL LEAVE THUNDERSTORMS OUT FOR
NOW. OTHERWISE...THE REST OF THE NIGHT LOOKS PARTLY CLOUDY...WHICH
ALONG WITH SLIGHTLY HIGHER DEWPOINTS...POINT TOWARD SLIGHTLY WARMER
MINS THAN LAST NIGHT AND CURRENT FORECAST LOWS APPEAR TO BE ON TRACK.
&&
.SYNOPSIS...
ISSUED AT 303 PM CDT THU JUL 31 2014
12Z UA ANALYSIS HAS AN 850MB LOW NEAR JAMES BAY AND ANOTHER ALONG
THE RED RIVER SOUTH OF KOUN. SEVERAL VERY WEAK TROFS RAN FROM THE
MID ATLANTIC STATES BACK INTO THE NORTHERN PLAINS. SATELLITE TRENDS
THROUGH MID AFTERNOON SHOW DIURNAL CLOUDS ACROSS THE AREA WITH SOME
CONVECTION ACROSS NORTHEAST WISCONSIN AND FAR WESTERN IOWA.
18Z SFC ANALYSIS HAS A WEAK LOW NORTHEAST OF KONL. SEVERAL WEAK
TROFS RAN FROM THE EASTERN GREAT LAKES INTO THE UPPER MIDWEST. DEW
POINTS WERE MAINLY IN THE 50S ACROSS THE MIDWEST WITH 60S FROM THE
SOUTHERN PLAINS INTO THE OHIO VALLEY.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 303 PM CDT THU JUL 31 2014
SATELLITE TRENDS SHOW SOME VERTICAL DEVELOPMENT IN THE CLOUDS ACROSS
NORTHERN ILLINOIS AND WEST OF KCID/KIOW. HOWEVER...THE VERTICAL
DEVELOPMENT IS VERY WEAK FOR PEAK HEATING. RAP TRENDS CONTINUE TO
SHOW THE INVERSION PRESENT ABOVE 700MB WHICH IS PLAYING INTO THE
LACK OF CONVECTION ACROSS THE AREA.
THE POSSIBILITY DOES EXIST FOR SOME VERY ISOLATED CONVECTION TO
OCCUR THROUGH SUNSET WITH THE FAR EAST AND WEST SECTIONS BEING
SLIGHTLY MORE FAVORED.
AFTER SUNSET...ANOTHER WEAK DISTURBANCE WILL ROTATE THROUGH THE
AREA. INITIALLY DOWNWARD MOTION IS OCCURRING ACROSS THE AREA BUT
SOME VERY WEAK LIFT DEVELOPS BY LATE EVENING AND CONTINUES
OVERNIGHT. THUS SOME ISOLATED SHOWERS MAY BE POSSIBLE THROUGH
SUNRISE.
IF DEVELOPMENT OCCURS WITH THE DISTURBANCE OVERNIGHT...LINGERING
SHOWERS WILL BE SEEN ACROSS THE AREA FRIDAY MORNING. HOWEVER...ANY
SHOWERS WOULD BE VERY ISOLATED IN NATURE.
DAYTIME HEATING AND THE APPROACH OF ANOTHER DISTURBANCE ALOFT SHOULD
FIRE OFF NEW DIURNAL CLOUDS BY MID DAY. THIS DISTURBANCE IS A BIT
STRONGER THAN PREVIOUS ONES SO THE POTENTIAL FOR AFTERNOON
CONVECTION IS EXPECTED TO BE SOMEWHAT HIGHER. AS SUCH...CONVECTION
SHOULD BE ISOLATED TO SCATTERED ACROSS THE AREA DURING THE AFTERNOON
HOURS.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 303 PM CDT THU JUL 31 2014
MAIN FORECAST FOCUS IS ON CHANGING LARGE SCALE PATTERN NEXT WEEK.
FRIDAY NIGHT THROUGH SATURDAY...LONG WAVE TROUGH OVER THE EASTERN
CONUS...WITH RESULTANT NORTHWEST FLOW OVER THE UPPER MIDWEST
DOMINATES THE START OF THE WEEKEND. MAIN SHORT WAVE DROPS ACROSS IA
AND MN FRIDAY NIGHT...BRINGING A REINFORCING COLD SURGE INTO THE
UPPER TROUGH. THUS SCATTERED CONVECTION REMAINS A POSSIBILITY FROM
FRIDAY EVENING THROUGH SATURDAY. WITHOUT A STRONG SURFACE
BOUNDARY... BEST CHANCES WILL OCCUR IN THE AFTERNOON AND EARLY
EVENING WITH PEAK HEATING. GIVEN THE COLD POOL ALOFT...COULD SEE
SOME PULSE TYPE STORMS WITH SMALL HAIL...ESPECIALLY FRIDAY EVENING.
SATURDAY IS SIMILAR...ALTHOUGH SOME MODELS SUGGEST SIGNIFICANT
SUBSIDENCE BY AFTERNOON THAT COULD SUPPRESS AND CONVECTION. THUS
HAVE HIGHEST POPS FRIDAY EVENING...THEN LOWER POPS SATURDAY
AFTERNOON.
SUNDAY...MAIN STORM TRACK REMAINS NORTH OF OUR AREA OVER MN
AND WI. THIS...COUPLED WITH WEAK RIDGING AT THE SURFACE SUGGESTS
QUIET WEATHER SUNDAY.
MONDAY THROUGH THURSDAY...THE RIDGE OVER THE SWRN US WILL SLOWLY
FLATTEN THROUGH THIS PERIOD...SETTING UP WEAK...GRADUALLY MORE
ZONAL FLOW OVER THE AREA. AT THE SURFACE...BOUNDARIES WILL BE IN
THE REGION. DEPENDING ON WHERE THOSE BOUNDARIES SET UP...WILL HAVE
SEVERAL OPPORTUNITIES FOR MCS/WIDESPREAD RAINFALL TO IMPACT OUR
CWFA...ESPECIALLY WEDNESDAY INTO THURSDAY WHEN THE GULF IS PROGGED
TO BE MORE OPEN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1137 PM CDT THU JUL 31 2014
WEAK SHOWERS...MOSTLY SPRINKLES...MAY BE IN THE BRL VICINITY
AROUND MIDNIGHT. OTHERWISE...THE REST OF TONIGHT AND FRIDAY WILL
HAVE MAINLY VFR CONDITIONS AND VERY LIGHT WINDS UNDER A BROAD
AREA OF HIGH PRESSURE AT THE SURFACE. LOW LEVEL MOISTURE MAY
AGAIN LEAD TO MORNING GROUND FOG...WHICH HAS BEEN INCLUDED WITH
POTENTIAL MVFR VISIBILITIES AT BOTH CID AND BRL. AT BRL...REPORTED
VISIBILITY MAY BE AFFECTED AT TIMES BY GRAVEL ROAD DUST IN THE
MORNING...MUCH AS IT WAS THURSDAY EVENING. SKIES WILL AGAIN BE
HAZY ALOFT AT ALL TERMINALS THROUGH FRIDAY DUE TO AN EXTENSIVE
PLUME OF THICK HIGH ALTITUDE SMOKE STREAMING SOUTH OUT OF WILDFIRES
IN NORTHERN CANADA. THERE WILL BE A CHANCE FOR AFTERNOON SHOWERS AND
THUNDERSTORMS...BUT THESE LOOK TO FEW TO MENTION IN THE TAFS IN THIS
TIMEFRAME.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...SHEETS
SYNOPSIS...08
SHORT TERM...08
LONG TERM...DMD
AVIATION...SHEETS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
339 PM CDT Fri Aug 1 2014
.SHORT TERM...(This Evening through Saturday)
Issued at 332 PM CDT FRI AUG 1 2014
Latest water vapor loops shows a shortwave axis moving over
Missouri with subsidence over eastern Kansas at 19Z. Surface trough
and low extended from northeast to southwest Kansas. Scattered
clouds have developed in layer around 750-700mb and forecast
soundings from the RUC show clouds dissolving by 02Z. Winds expected
to become easterly this evening as the surface low and trough moves
into southeast Kansas. Some isentropic lift develops after 06Z
tonight with low condensation pressure deficits over east central
Kansas. NAM has best lift over southeast Kansas after 09Z on the
305K isentropic surface. Have kept in some partly cloudy skies in
east central Kansas later tonight and into early Saturday morning.
There is little in the way of upper support, but could see some
isolated very light showers or sprinkles develop in the isentropic
lift and models have shown over the last few runs. Lows tonight will
range from the lower to mid 60s.
Saturday, the northwest upper flow continues with heights rising
slightly through the day. Expect highs to be a few degrees warmer
out toward central Kansas and similar to today. Some small chances
of showers are possible on Saturday with weak embedded waves and
some weak isentropic lift especially in the morning. With nothing
showing up upstream in water vapor will keep the dry forecast going.
Models show a 700 mb wave over north central Nebraska Saturday
afternoon. The NAM develops some showers and isolated thunderstorms
across central and parts of east central Kansas in a zone of
700-500mb frontogenesis in the afternoon. Slight warming aloft may
inhibit any precipitation from forming and will increase pops but
remain less than 15 percent attm.
.LONG TERM...(Saturday Night through Friday)
Issued at 332 PM CDT FRI AUG 1 2014
A board upper level ridge across the west-central conus will
gradually build east across the southern plains by mid week.
Weak upper level troughs embedded in northwesterly flow aloft may
provide enough ascent when combined with weak isentropic lift at
night for isolated showers Saturday Night through Sunday night. At
this time I will only carry 10 to 14 pops due to the uncertainty on
areal coverage and timing. Highs on Sunday will be in the upper 80s
to lower 90s. lows will be in the 60s.
It looks dry Monday through Tuesday as the upper level ridge
builds eastward into the southern plains. Highs will be in the lower
to mid 90s. lows will be in the upper 60s to lower 70s.
Tuesday Night through Thursday, A series of upper level troughs will
round the upper level ridge axis across the northern and central
plains. A cold front will also push southward into eastern KS on
Wednesday and may stall out across the CWA through Thursday. The
combination of ascent ahead of the upper level troughs and surface
convergence along the surface cold front will provide the CWA with
chances for showers and thunderstorms. Highs will gradually cool
into the mid 80s to lower 90s, with overnight lows in the mid 60s
to lower 70s.
&&
.AVIATION...(For the 18Z TAFs through 18Z Saturday Afternoon)
Issued at 1235 PM CDT FRI AUG 1 2014
VFR conditions expected through the period. Winds near 10 kts at
TOP and FOE through 22Z then becoming east under 10 kts through
the end of the period.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...53
LONG TERM...Gargan
AVIATION...53
AREA FORECAST DISCUSSION
NWS JACKSON KY
1110 PM EDT SAT AUG 2 2014
.UPDATE...
ISSUED AT 1110 PM EDT SAT AUG 2 2014
FOG HAS DEVELOPED AND INTENSIFIED EARLY THIS EVENING...AND IS
BECOMING MORE WIDESPREAD ACROSS THE NORTHEASTERN TWO THIRDS OF THE
CWA. BEEFED UP THE FOG IN THE GRIDS AND ZONES FOR THE REMAINDER OF
THE OVERNIGHT PERIOD. AS WE ARE HEADING INTO SUNDAY...IMPACT SHOULD
BE RELATIVELY LOW AS FOG SHOULD HAVE BEGUN TO LIFT BY THE TIME CHURCH
GOERS GET OUT. ALSO AM NOT CONVINCED FOG WILL BE WIDESPREAD ENOUGH
TO WARRANT HEADLINES. HIT THE FOG HARDEST ALONG AND NORTHEAST OF A
IRVINE TO MANCHESTER TO WHITESBURG LINE...WHERE LOCATIONS MOST LIKELY
SAW EVENING CONVECTION AND RAINFALL. ISSUED A SPECIAL WEATHER
STATEMENT TO HIGHLIGHT FOG FOR THESE AREAS. FURTHER SOUTHWEST WHERE
LESS RAIN WAS EVIDENT WENT WITH PATCHY DENSE WORDING IN THE ZONES AND
GRIDS. ALSO TWEAKED GRIDS FOR HOURLY TRENDS. NO OTHER CHANGES TO THE
FORECAST PACKAGE ATTM.
UPDATE ISSUED AT 827 PM EDT SAT AUG 2 2014
CONVECTIVE ACTIVITY IS DISSIPATING AT A RAPID PACE THIS EVENING AS
AIR MASS IN PLACE STABILIZES. WILL REMOVE ALL MENTION OF THUNDER
WITH NEXT UPDATE...AND POSSIBLY ALL POPS. FOG WILL LIKELY FORM
THROUGH THE OVERNIGHT PERIOD. POTENTIAL IS ADDRESSED WELL IN THE
PRESENT FORECAST. OTHERWISE BROUGHT GRIDS IN LINE WITH HOURLY OBS AND
FRESHENED UP ZONE WORDING.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 301 PM EDT SAT AUG 2 2014
THE HRRR MODEL SEEMED TO HAVE THE BEST HANDLE ON THE SHOWER AND STORM
ACTIVITY THAT HAS BEEN ONGOING ACROSS EASTERN KENTUCKY FOR THE PAST
FEW HOURS. THEREFORE...THE HRRR SOLUTION WAS USED TO CREATE THE NEW
FORECAST PRECIPITATION PROBABILITIES FOR THE AREA FOR THE REST OF
THIS AFTERNOON THROUGH 2Z THIS EVENING. AFTER 2Z TONIGHT...THE NAM12
MODEL WAS USED. SHOWERS AND STORMS ARE EXPECTED TO PERSIST THROUGH
ROUGHLY 2Z THIS EVENING...WITH THE PEAK ACTIVITY OCCURRING DURING
PEAK HEATING HOURS THIS AFTERNOON. A SHORTWAVE TROUGH INTERACTING
WITH LIMITED LOW LEVEL MOISTURE IS THE DRIVING FORCE FOR
PRECIPITATION THIS AFTERNOON...AND WILL BE UNTIL THE TROUGH MOVES
EAST OF THE AREA EARLY THIS EVENING. SOME OF THE STORMS THIS
AFTERNOON HAVE BEEN A BIT STRONG AND CAPABLE OF PRODUCING SMALL
HAIL...LOCALLY HEAVY RAINFALL...AND WIND GUSTS UP TO 30 MPH. AFTER
THIS EVENING...HIGH PRESSURE WILL SETTLE OVER THE AREA...ALLOWING FOR
A DRIER AND SLIGHTLY WARMER PATTERN. HIGHS ON SUNDAY ARE EXPECTED TO
RISE INTO THE LOW TO MID 80S UNDER AMPLE SUNSHINE AND LIGHT WINDS.
LOWS THE NEXT COUPLE OF NIGHTS WILL BOTTOM OUT AROUND 60...WHICH IS
A BIT BELOW NORMAL FOR THIS TIME OF YEAR. THE WEATHER RELATED ISSUED
TO LOOK OVERNIGHT WILL BE FOG FORMATION. FOG WILL BE POSSIBLE IN OUR
RIVER VALLEYS OVERNIGHT. THE MAIN QUESTION WILL BE THE EXTENT AND
DENSITY OF FOG THAT FORMS WHERE PRECIPITATION HAS ALREADY OCCURRED
TODAY. THE OTHER FACTOR INVOLVED WITH THE FOG WILL BE THE AMOUNT OF
CLOUD COVER THAT PERSISTS OVERNIGHT. IF THE CLOUDS CLEAR OUT MORE
QUICKLY THEN FOG FORMATION WILL BE FAVORED...PARTICULARLY FOR
LOCATIONS WHERE IT RAINED TODAY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 403 PM EDT SAT AUG 2 2014
THE MODELS REMAIN IN DECENT AGREEMENT WITH THE LONG WAVE PATTERN
THROUGH NEXT WEEKEND. OVERALL...THE FLOW LOOKS TO FLATTEN OUT ACROSS
THE MISSISSIPPI VALLEY...WITH THE DEEPER AND PERSISTENT TROUGHING
BECOMING MORE CONFINED TO THE NORTHEASTERN CONUS.
FOR EASTERN KENTUCKY...DRY WEATHER WILL HANG IN THROUGH
TUESDAY...BEFORE A COLD FRONT SAGS SOUTHEAST AND EVENTUALLY STALLS
ACROSS OUR VICINITY. DAILY CHANCES OF SCATTERED SHOWERS AND
THUNDERSTORMS WILL REIGN FROM TUESDAY NIGHT THROUGH NEXT WEEKEND.
STAYED CLOSE TO THE BLENDED GUIDANCE...ALTHOUGH DID UNDERCUT A BIT IN
THE POPS FURTHER OUT GIVEN THE LOW CONFIDENCE IN TRYING TO NAIL DOWN
SMALLER SCALE FEATURES. TEMPERATURES WILL AVERAGE NEAR NORMAL THROUGH
THE PERIOD AS WELL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 827 PM EDT SAT AUG 2 2014
PRIMARY ISSUES FOR THIS FORECAST PERIOD WILL BE THE POTENTIAL FOR FOG
OVERNIGHT. WITH RECENT RAINFALL ACROSS MUCH OF THE AREA AND CHANGE OF
AIR MASS BEHIND FRONTAL BOUNDARY DECIDED TO STICK CLOSE TO MODEL
GUIDANCE...BUT NOT QUITE AS PESSIMISTIC. CONSEQUENTLY CAN EXPECT
TYPICAL MVFR VSBYS CLOSE TO MIDNIGHT...LIFR CONDITIONS DURING THE
EARLY MORNING...PREDAWN HOURS OF SUNDAY. WINDS WILL BE LIGHT...
VEERING MORE NORTHERLY WITH TIME AT ABOUT 3-5 KTS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...RAY
SHORT TERM...AR
LONG TERM...GEOGERIAN
AVIATION...RAY
AREA FORECAST DISCUSSION
NWS JACKSON KY
827 PM EDT SAT AUG 2 2014
.UPDATE...
ISSUED AT 827 PM EDT SAT AUG 2 2014
CONVECTIVE ACTIVITY IS DISSIPATING AT A RAPID PACE THIS EVENING AS
AIR MASS IN PLACE STABILIZES. WILL REMOVE ALL MENTION OF THUNDER
WITH NEXT UPDATE...AND POSSIBLY ALL POPS. FOG WILL LIKELY FORM
THROUGH THE OVERNIGHT PERIOD. POTENTIAL IS ADDRESSED WELL IN THE
PRESENT FORECAST. OTHERWISE BROUGHT GRIDS IN LINE WITH HOURLY OBS AND
FRESHENED UP ZONE WORDING.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 301 PM EDT SAT AUG 2 2014
THE HRRR MODEL SEEMED TO HAVE THE BEST HANDLE ON THE SHOWER AND STORM
ACTIVITY THAT HAS BEEN ONGOING ACROSS EASTERN KENTUCKY FOR THE PAST
FEW HOURS. THEREFORE...THE HRRR SOLUTION WAS USED TO CREATE THE NEW
FORECAST PRECIPITATION PROBABILITIES FOR THE AREA FOR THE REST OF
THIS AFTERNOON THROUGH 2Z THIS EVENING. AFTER 2Z TONIGHT...THE NAM12
MODEL WAS USED. SHOWERS AND STORMS ARE EXPECTED TO PERSIST THROUGH
ROUGHLY 2Z THIS EVENING...WITH THE PEAK ACTIVITY OCCURRING DURING
PEAK HEATING HOURS THIS AFTERNOON. A SHORTWAVE TROUGH INTERACTING
WITH LIMITED LOW LEVEL MOISTURE IS THE DRIVING FORCE FOR
PRECIPITATION THIS AFTERNOON...AND WILL BE UNTIL THE TROUGH MOVES
EAST OF THE AREA EARLY THIS EVENING. SOME OF THE STORMS THIS
AFTERNOON HAVE BEEN A BIT STRONG AND CAPABLE OF PRODUCING SMALL
HAIL...LOCALLY HEAVY RAINFALL...AND WIND GUSTS UP TO 30 MPH. AFTER
THIS EVENING...HIGH PRESSURE WILL SETTLE OVER THE AREA...ALLOWING FOR
A DRIER AND SLIGHTLY WARMER PATTERN. HIGHS ON SUNDAY ARE EXPECTED TO
RISE INTO THE LOW TO MID 80S UNDER AMPLE SUNSHINE AND LIGHT WINDS.
LOWS THE NEXT COUPLE OF NIGHTS WILL BOTTOM OUT AROUND 60...WHICH IS
A BIT BELOW NORMAL FOR THIS TIME OF YEAR. THE WEATHER RELATED ISSUED
TO LOOK OVERNIGHT WILL BE FOG FORMATION. FOG WILL BE POSSIBLE IN OUR
RIVER VALLEYS OVERNIGHT. THE MAIN QUESTION WILL BE THE EXTENT AND
DENSITY OF FOG THAT FORMS WHERE PRECIPITATION HAS ALREADY OCCURRED
TODAY. THE OTHER FACTOR INVOLVED WITH THE FOG WILL BE THE AMOUNT OF
CLOUD COVER THAT PERSISTS OVERNIGHT. IF THE CLOUDS CLEAR OUT MORE
QUICKLY THEN FOG FORMATION WILL BE FAVORED...PARTICULARLY FOR
LOCATIONS WHERE IT RAINED TODAY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 403 PM EDT SAT AUG 2 2014
THE MODELS REMAIN IN DECENT AGREEMENT WITH THE LONG WAVE PATTERN
THROUGH NEXT WEEKEND. OVERALL...THE FLOW LOOKS TO FLATTEN OUT ACROSS
THE MISSISSIPPI VALLEY...WITH THE DEEPER AND PERSISTENT TROUGHING
BECOMING MORE CONFINED TO THE NORTHEASTERN CONUS.
FOR EASTERN KENTUCKY...DRY WEATHER WILL HANG IN THROUGH
TUESDAY...BEFORE A COLD FRONT SAGS SOUTHEAST AND EVENTUALLY STALLS
ACROSS OUR VICINITY. DAILY CHANCES OF SCATTERED SHOWERS AND
THUNDERSTORMS WILL REIGN FROM TUESDAY NIGHT THROUGH NEXT WEEKEND.
STAYED CLOSE TO THE BLENDED GUIDANCE...ALTHOUGH DID UNDERCUT A BIT IN
THE POPS FURTHER OUT GIVEN THE LOW CONFIDENCE IN TRYING TO NAIL DOWN
SMALLER SCALE FEATURES. TEMPERATURES WILL AVERAGE NEAR NORMAL THROUGH
THE PERIOD AS WELL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 827 PM EDT SAT AUG 2 2014
PRIMARY ISSUES FOR THIS FORECAST PERIOD WILL BE THE POTENTIAL FOR FOG
OVERNIGHT. WITH RECENT RAINFALL ACROSS MUCH OF THE AREA AND CHANGE OF
AIR MASS BEHIND FRONTAL BOUNDARY DECIDED TO STICK CLOSE TO MODEL
GUIDANCE...BUT NOT QUITE AS PESSIMISTIC. CONSEQUENTLY CAN EXPECT
TYPICAL MVFR VSBYS CLOSE TO MIDNIGHT...LIFR CONDITIONS DURING THE
EARLY MORNING...PREDAWN HOURS OF SUNDAY. WINDS WILL BE LIGHT...
VEERING MORE NORTHERLY WITH TIME AT ABOUT 3-5 KTS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...RAY
SHORT TERM...AR
LONG TERM...GEOGERIAN
AVIATION...RAY
AREA FORECAST DISCUSSION
NWS JACKSON KY
434 PM EDT FRI AUG 1 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 300 PM EDT FRI AUG 1 2014
THE MODELS WERE IN MODEST AGREEMENT THIS GO ROUND...WITH EACH
RESPECTIVE MODEL HAVING VARYING DEGREES OF DIFFICULTY RESOLVING THE
CONVECTIVE ACTIVITY THAT HAS BEEN TAKING PLACE THIS AFTERNOON. ALL IN
ALL...THE SREF AND HRRR MODELS SEEMED TO HAVE THE BEST HANDLE ON
THINGS...SO THOSE TWO MODELS WERE USED TO FORMULATE THE FIRST 36
HOURS OF THE NEW FORECAST. ISOLATED TO SCATTERED SHOWERS AND STORMS
ARE EXPECTED TO CONTINUE THROUGH EARLY THIS EVENING...AS AN
DISTURBANCE IN THE MIDDLE AND UPPER LEVELS OF THE ATMOSPHERE MAKES
ITS WAY ACROSS THE OHIO VALLEY. THIS ACTIVITY WILL TAPER OFF QUICKLY
AFTER SUNSET...WITH NO SHOWERS OR STORMS EXPECTED AFTER 4Z. ANOTHER
ROUND OF SHOWERS AND STORMS IS EXPECTED ON SATURDAY AS YET ANOTHER
DISTURBANCE...AND EVENTUALLY A SURFACE COLD FRONT...MOVE ACROSS THE
AREA. THE ACTIVITY ON SATURDAY WILL LIKELY BE A BIT MORE WIDESPREAD
DUE TO THE PASSAGE OF A COLD FRONT. THEREFORE...THE PRECIPITATION
CHANCES FOR TOMORROW ON AVERAGE WILL BE HIGHER THAN WHAT WAS FORECAST
FOR TODAY. TEMPERATURES WILL CONTINUE TO RUN SLIGHTLY BELOW NORMAL
FOR THIS TIME OF YEAR...WITH HIGHS TOMORROW RISING IN THE UPPER 70S
AND LOWER 80S ACROSS THE BOARD. OVERNIGHT LOWS TONIGHT AND TOMORROW
NIGHT WILL ALSO BE SLIGHTLY BELOW NORMAL...WITH READINGS BOTTOMING
OUT MOSTLY IN THE LOWER 60S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 434 PM EDT FRI AUG 1 2014
A LARGE UPPER TROUGH WILL REMAIN IN PLACE OVER THE REGION UNTIL LATE
IN THE PERIOD. HOWEVER...LOW LEVEL MOISTURE WILL BE LACKING...WITH
GULF OF MEXICO MOISTURE ALSO CUT OFF UNTIL AROUND THE END OF THE
PERIOD. THIS SHOULD RESULT IN CLEAR TO PARTLY CLOUDY SKIES THROUGH
TUESDAY. VERY ISOLATED SHOWERS/THUNDERSTORMS CAN NOT BE RULED OUT
DURING PEAK HEATING SUNDAY THROUGH TUESDAY...BUT THE PROBABILITY IS
TOO LOW TO WARRANT 20 PERCENT POPS BEING INCLUDED IN THE FORECAST.
MODELS SHOW A REINFORCEMENT OF THE MID/UPPER LEVEL TROUGH ON
WEDNESDAY...WITH AN ASSOCIATED SURFACE COLD FRONT SWINGING THROUGH
THE LOCAL AREA. EVEN WITH MEAGER MOISTURE...THIS COULD BE ENOUGH TO
INCREASE PRECIP COVERAGE...AND A SLIGHT CHANCE WAS USED ON
WEDNESDAY. THIS REINFORCING WAVE IS EXPECTED TO BE PROGRESSIVE...AND
CARRY THE LARGER SCALE TROUGH ON TO THE EAST...AS AN UPPER RIDGE
WHICH HAS PERSISTED OVER THE ROCKIES ALSO BREAKS DOWN. IN RESPONSE...
SURFACE FEATURES WILL ALSO UNDERGO A TRANSITION...AND FLOW OFF THE
GULF SHOULD FINALLY MAKE A COMEBACK. LOW POPS WERE USED FROM THURSDAY
ONWARD DUE TO BETTER MOISTURE AVAILABILITY...BUT ONLY WEAK FEATURES
ALOFT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 127 PM EDT FRI AUG 1 2014
EXPECTED VFR CONDITIONS TO PREVAIL AT THE TAF SITES THROUGH AROUND 6Z
TONIGHT. ISOLATED TO SCATTERED SHOWERS AND STORMS WERE ONGOING ALONG
THE VIRGINIA BORDER AT TAF ISSUANCE...AND THIS ACTIVITY IS EXPECTED
TO SPREAD WESTWARD THROUGHOUT THE REST OF THE DAY. THE MORE
WIDESPREAD SHOWERS AND STORMS ARE EXPECTED TO FORM OVER OUR HIGHER
TERRAIN EAST OF THE WEATHER OFFICE...AS A DISTURBANCE IN THE MIDDLE
OF THE ATMOSPHERE INTERACTS WITH THE MOUNTAINS. THE SHOWERS AND
STORMS ARE EXPECTED TO DECREASE TO ISOLATED COVERAGE OVERNIGHT. FOG
WILL BE ON TAP BETWEEN 5 AND 12Z...PARTICULARLY FOR LOCATIONS THE
RECEIVE RAINFALL DURING THE DAY TODAY. THE FOG COULD BECOME DENSE AT
TIMES BETWEEN 8 AND 12Z. IN GENERAL...MVFR CONDITIONS ARE EXPECTED AT
JKL AND SJS. LOZ AND SME COULD SEE PERIODS OF IFR OR EVEN LIFR
CONDITIONS IF THE FOG BECOME DENSE AND PERSISTENT ENOUGH AFTER 8 OR
9Z TONIGHT. MORE RAIN IS POSSIBLE ON SATURDAY...AS YET ANOTHER UPPER
LEVEL WEATHER SYSTEM MOVES ACROSS THE OHIO VALLEY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AR
LONG TERM...HAL
AVIATION...AR
AREA FORECAST DISCUSSION
NWS JACKSON KY
300 PM EDT FRI AUG 1 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 300 PM EDT FRI AUG 1 2014
THE MODELS WERE IN MODEST AGREEMENT THIS GO ROUND...WITH EACH
RESPECTIVE MODEL HAVING VARYING DEGREES OF DIFFICULTY RESOLVING THE
CONVECTIVE ACTIVITY THAT HAS BEEN TAKING PLACE THIS AFTERNOON. ALL IN
ALL...THE SREF AND HRRR MODELS SEEMED TO HAVE THE BEST HANDLE ON
THINGS...SO THOSE TWO MODELS WERE USED TO FORMULATE THE FIRST 36
HOURS OF THE NEW FORECAST. ISOLATED TO SCATTERED SHOWERS AND STORMS
ARE EXPECTED TO CONTINUE THROUGH EARLY THIS EVENING...AS AN
DISTURBANCE IN THE MIDDLE AND UPPER LEVELS OF THE ATMOSPHERE MAKES
ITS WAY ACROSS THE OHIO VALLEY. THIS ACTIVITY WILL TAPER OFF QUICKLY
AFTER SUNSET...WITH NO SHOWERS OR STORMS EXPECTED AFTER 4Z. ANOTHER
ROUND OF SHOWERS AND STORMS IS EXPECTED ON SATURDAY AS YET ANOTHER
DISTURBANCE...AND EVENTUALLY A SURFACE COLD FRONT...MOVE ACROSS THE
AREA. THE ACTIVITY ON SATURDAY WILL LIKELY BE A BIT MORE WIDESPREAD
DUE TO THE PASSAGE OF A COLD FRONT. THEREFORE...THE PRECIPITATION
CHANCES FOR TOMORROW ON AVERAGE WILL BE HIGHER THAN WHAT WAS FORECAST
FOR TODAY. TEMPERATURES WILL CONTINUE TO RUN SLIGHTLY BELOW NORMAL
FOR THIS TIME OF YEAR...WITH HIGHS TOMORROW RISING IN THE UPPER 70S
AND LOWER 80S ACROSS THE BOARD. OVERNIGHT LOWS TONIGHT AND TOMORROW
NIGHT WILL ALSO BE SLIGHTLY BELOW NORMAL...WITH READINGS BOTTOMING
OUT MOSTLY IN THE LOWER 60S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 300 PM EDT FRI AUG 1 2014
AN EXTENDED DISCUSSION WILL BE ISSUED SHORTLY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 127 PM EDT FRI AUG 1 2014
EXPECTED VFR CONDITIONS TO PREVAIL AT THE TAF SITES THROUGH AROUND 6Z
TONIGHT. ISOLATED TO SCATTERED SHOWERS AND STORMS WERE ONGOING ALONG
THE VIRGINIA BORDER AT TAF ISSUANCE...AND THIS ACTIVITY IS EXPECTED
TO SPREAD WESTWARD THROUGHOUT THE REST OF THE DAY. THE MORE
WIDESPREAD SHOWERS AND STORMS ARE EXPECTED TO FORM OVER OUR HIGHER
TERRAIN EAST OF THE WEATHER OFFICE...AS A DISTURBANCE IN THE MIDDLE
OF THE ATMOSPHERE INTERACTS WITH THE MOUNTAINS. THE SHOWERS AND
STORMS ARE EXPECTED TO DECREASE TO ISOLATED COVERAGE OVERNIGHT. FOG
WILL BE ON TAP BETWEEN 5 AND 12Z...PARTICULARLY FOR LOCATIONS THE
RECEIVE RAINFALL DURING THE DAY TODAY. THE FOG COULD BECOME DENSE AT
TIMES BETWEEN 8 AND 12Z. IN GENERAL...MVFR CONDITIONS ARE EXPECTED AT
JKL AND SJS. LOZ AND SME COULD SEE PERIODS OF IFR OR EVEN LIFR
CONDITIONS IF THE FOG BECOME DENSE AND PERSISTENT ENOUGH AFTER 8 OR
9Z TONIGHT. MORE RAIN IS POSSIBLE ON SATURDAY...AS YET ANOTHER UPPER
LEVEL WEATHER SYSTEM MOVES ACROSS THE OHIO VALLEY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AR
LONG TERM...HAL
AVIATION...AR
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1230 PM CDT Fri Aug 1 2014
.UPDATE...
Updated aviation section for the 18Z TAF issuance
&&
.SHORT TERM...(Today through Sunday)
Issued at 305 AM CDT FRI AUG 1 2014
Will be monitoring the patchy and shallow dense fog across much of
the area again this morning. See no reason why it wouldn`t be
similar to yesterday`s development.
A sharper mid/upper level trough will develop within the broad
cyclonic flow over the region through tonight, but the 00Z models
are a bit weaker and farther east with it compared to yesterday`s
runs. It will push just east of the area by Saturday evening.
In the low-levels, weak warm advection is noted within the KPAH
VAD wind profile, but the surface pressure pattern is very flat. A
minor push of surface high pressure into the area is expected in
the wake of the upper trough late Saturday into Sunday.
The weak warm advection over southeast Missouri may result in some
isolated shower activity this morning. The NAM soundings in western
portions of southeast Missouri indicate a shallow layer of
instability based around 7kft, and the HRRR develops showers
northward into that area from the Boot Heel region and northeast
Arkansas through the morning. The soundings dry up by 18Z, but as
the mid/upper trough develops southward toward our region, a small
chance of deep convection exists across northern portions of
southern Illinois in the late afternoon and possibly into the
early evening. If a storm develops it should be short-lived and
rather weak.
With the upper trough over the eastern half of the region
Saturday, isolated diurnal showers and thunderstorms can be
expected generally along and east of the Mississippi River. Once
again any storms should be short-lived and rather weak.
As for temperatures, the consensus of rather tightly grouped guidance
looks pretty good through the period.
.LONG TERM...(Sunday Night through Friday Night)
Issued at 305 AM CDT FRI AUG 1 2014
High Pressure aloft dominates the WFO PAH forecast area through 12z
Thursday. effectively suppressing convection across the region.
Between 18z Wednesday and 18z Thursday, the latest 00z Friday medium
range model guidance begin to differ sharply in the position of a
deepening shortwave in the Upper Midwest/Northern Plains region.
This significantly impacts the rapidly evolving baroclinic zone to
the northwest of the WFO PAH forecast area. The ECMWF sets up a warm
advection flow with convection being developed along a warm front
developing over the Tri-State region (Southwest IN, Northwest
Kentucky, Southeast Illinois. The GFS keeps the WFO PAH forecast
area in the warm sector ahead of the impressed warm and cold fronts.
By Thursday, the movement and deepening of the Upper
Midwest/Northern Plains low continues to differ sharply with the
GFS/ECMWF/NAM guidance in locations and to a lesser degree timing of
upstream convection. Regardless of the latest solution, slowed down
the onset of convection into the area into Thursday.
Beyond Thursday, the east-southeast movement and deepening of the
Upper Midwest/Northern Plains shortwave transitions into an upper
Low over the Great Lakes by late Friday night. Although there is
some initial concern on the timing of the precipitation into the WFO
PAH CWA, this becomes a moot point Thursday into Friday as the
baroclinic zone becomes stretched across the area, prolonging rain
chances across the area. In fact, several of the recent model runs
are consistent in keeping higher than normal PoPs/Weather in place
during this time period.
Therefore, PoPs and Weather have been included for the period from
next Thursday into Friday. All other forecast changes minor, with
the exception of those sensible weather elements impacted by the
forecast convection.
&&
.AVIATION...
Issued at 1230 PM CDT FRI AUG 1 2014
For the southern terminals /kcgi and kpah/...mid level cigs around
10k feet will persist through this evening in advance of a
southeastward moving upper level disturbance. Once skies clear out
later tonight...there will likely be some fog as winds become calm.
Conditions should be similar to early this morning. The fog will
burn off quickly within a couple hours after sunrise.
For the northern terminals /kevv and kowb/...cumulus clouds will
gradually increase this afternoon but should remain scattered for
the most part. A mid level cloud deck will arrive early this evening
in advance of an upper level disturbance. Could not rule out some
showers this evening...but probabilities are too low to include in
tafs. Skies will clear out by early Saturday morning.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...DRS
LONG TERM...Smith
AVIATION...MY
AREA FORECAST DISCUSSION
NWS JACKSON KY
127 PM EDT FRI AUG 1 2014
.UPDATE...
ISSUED AT 127 PM EDT FRI AUG 1 2014
MADE A FEW MINOR TWEAKS TO THE FORECAST SINCE THE LAST UPDATE. SOME
SHOWERS AND STORMS HAVE POPPED UP OVER OUR VIRGINIA BORDER COUNTIES
OVER THE PAST HOUR OR SO...WHICH WAS A LITTLE BIT LATER IN THE DAY
THAN ORIGINALLY FORECAST. THEREFORE...THE FORECAST GRIDS WERE UPDATED
TO REFLECT THE LATER THAN ANTICIPATED SHOWER AND STORM ACTIVITY. SINCE
THINGS GOT GOING A BIT LATER...ALSO DECIDED TO SLIGHTLY LOWER
PRECIPITATION CHANCES ACROSS THE BOARD. THE REST OF THE FORECAST WAS
IN GOOD SHAPE AS IS WITH NO OTHER CHANGES MADE.
UPDATE ISSUED AT 955 AM EDT FRI AUG 1 2014
UPDATED THE ZONE FORECAST TEXT PRODUCT TO REMOVE MENTION OF FOG NOT
THAT ALL THE FOG HAS BURNED OFF AROUND THE AREA. LEFT IN MENTION OF
LATE MORNING THROUGH EARLY EVENING SHOWER AND STORM CHANCES AS THE
LATEST DATA FROM THE SREF AND HRRR BOTH STILL SUPPORTING IT. WILL
MONITOR THAT PART OF THE FORECAST OVER THE NEXT FEW HOURS TO
DETERMINE IF ANOTHER UPDATE WILL BE NEEDED.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 326 AM EDT FRI AUG 1 2014
THE MODELS START OUT IN GOOD AGREEMENT WITH AN UPPER LOW NEAR HUDSONS
BAY. THE KEY FEATURE IS A SHORT WAVE MOVING DOWN THE BACK SIDE OF THE
UPPER TROUGH. THIS SHORT WAVE IS FORECAST TO INTENSIFY AS IT DIPS
SOUTH INTO THE CENTRAL US. BY TONIGHT...THE SHORT WAVE WILL EXTEND
FROM LAKE SUPERIOR SOUTH ACROSS CENTRAL ILLINOIS INTO LOUISIANA. WITH
THIS SYNOPTIC PATTERN...THE COLD FRONT IS WELL THE SOUTH OF THE AREA
ALONG THE GULF COAST AND THE BLOCKING RIDGE OUT WEST IS BLOCKING ANY
FRONTS FROM MOVING INTO THE AREA. THE SHORT WAVE TROUGH AXIS IS FORECAST
TO MOVE ACROSS EASTERN KENTUCKY ON SATURDAY EVENING. THE MODELS ARE
IN GOOD AGREEMENT WITH THE TIMING OF THE TROUGH PASSAGE. THE MAIN
DRIVER OF THE WEATHER WILL BE THE GENERAL INSTABILITY ASSOCIATED WITH
THE UPPER LOW AND THEN THE PASSING OF THE UPPER TROUGH AXIS. THERE
HAS BEEN SOME MID LEVEL CAPPING THAT HAS HELD DOWN ANY CLOUDS FROM
GROWING BIG ENOUGH TO PRODUCE RAIN SHOWERS. AS THE TROUGH NEARS...THE
MID LEVEL CAPPING WILL BEGIN TO ERODE AND THE NET RESULT IS THAT SOME
ISOLATED TO SCATTERED THUNDERSTORMS AND SHOWERS WILL BE ABLE TO FORM.
THERE ARE ENOUGH DIFFERENCES IN HOW THE MODELS HANDLE THIS
SYSTEM...THAT CONFIDENCE IS LOWER THAN NORMAL WITH HOW WIDESPREAD
THE PRECIPITATION WILL BE. THERE COULD BE A SCENARIO WHERE THE ENERGY
WILL PASS TO THE NORTH AND SOUTH OF THE AREA AND THERE WILL BE
MINIMAL CONVECTION OF EASTERN KENTUCKY. THE PROBABILITY OF
PRECIPITATION IS A BIT LOWER THAN WHAT THE PREVIOUS FORECASTS HAD.
FOR TEMPERATURES USED A BLEND OF THE NAM AND GFS MOS AND THEN MADE
SOME ADJUSTMENTS FOR TERRAIN EFFECTS.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 AM EDT FRI AUG 1 2014
THE PERSISTENT TROUGH OVER THE EASTERN U.S. WILL DEAMPLIFY A BIT
THROUGH THE LONG TERM PERIOD BUT REMAIN PRETTY MUCH IN PLACE IN THE
MEANS. A PASSING SHORTWAVE WILL KEEP THE THREAT OF SHOWERS/STORMS IN
OUR FORECAST FOR SATURDAY NIGHT AND SUNDAY. WEAK HIGH PRESSURE WILL
THEN BUILD INTO THE REGION BY EARLY NEXT WEEK AND MOST LOCATIONS
SHOULD BE DRY AS A RESULT WITH THE EXCEPTION OF ALONG THE VIRGINIA
BORDER WHERE PROXIMITY TO DEEPER MOISTURE JUST TO OUR SOUTHEAST MAY
ALLOW A FEW SHOWERS/STORMS TO FIRE WITH DAYTIME HEATING MONDAY
AFTERNOON. A COLD FRONT WILL SAG SOUTHWARD SLOWLY THROUGH TIME INTO
THE OHIO VALLEY. MOST MODELS KEEP THIS FRONT WELL TO OUR NORTH
THROUGH MIDWEEK...BUT THE 01/00Z ECMWF SHIFTED COURSE AND IS AN
OUTLIER DROPPING IT ALL THE WAY THROUGH OUR AREA. WILL CONTINUE WITH
A DRY FORECAST FOR NOW THROUGH WEDNESDAY BEFORE RAIN CHANCES
INCREASE AGAIN ON THURSDAY AS THE FRONT APPROACHES. TEMPERATURES
WILL MODERATE SLOWLY THROUGH TIME BUT ONLY UP TO NORMAL LEVELS FOR
EARLY AUGUST BY WEDNESDAY AND THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 127 PM EDT FRI AUG 1 2014
EXPECTED VFR CONDITIONS TO PREVAIL AT THE TAF SITES THROUGH AROUND 6Z
TONIGHT. ISOLATED TO SCATTERED SHOWERS AND STORMS WERE ONGOING ALONG
THE VIRGINIA BORDER AT TAF ISSUANCE...AND THIS ACTIVITY IS EXPECTED
TO SPREAD WESTWARD THROUGHOUT THE REST OF THE DAY. THE MORE
WIDESPREAD SHOWERS AND STORMS ARE EXPECTED TO FORM OVER OUR HIGHER
TERRAIN EAST OF THE WEATHER OFFICE...AS A DISTURBANCE IN THE MIDDLE
OF THE ATMOSPHERE INTERACTS WITH THE MOUNTAINS. THE SHOWERS AND
STORMS ARE EXPECTED TO DECREASE TO ISOLATED COVERAGE OVERNIGHT. FOG
WILL BE ON TAP BETWEEN 5 AND 12Z...PARTICULARLY FOR LOCATIONS THE
RECEIVE RAINFALL DURING THE DAY TODAY. THE FOG COULD BECOME DENSE AT
TIMES BETWEEN 8 AND 12Z. IN GENERAL...MVFR CONDITIONS ARE EXPECTED AT
JKL AND SJS. LOZ AND SME COULD SEE PERIODS OF IFR OR EVEN LIFR
CONDITIONS IF THE FOG BECOME DENSE AND PERSISTENT ENOUGH AFTER 8 OR
9Z TONIGHT. MORE RAIN IS POSSIBLE ON SATURDAY...AS YET ANOTHER UPPER
LEVEL WEATHER SYSTEM MOVES ACROSS THE OHIO VALLEY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AR
SHORT TERM...JJ
LONG TERM...ABE
AVIATION...AR
AREA FORECAST DISCUSSION
NWS JACKSON KY
955 AM EDT FRI AUG 1 2014
.UPDATE...
ISSUED AT 955 AM EDT FRI AUG 1 2014
UPDATED THE ZONE FORECAST TEXT PRODUCT TO REMOVE MENTION OF FOG NOT
THAT ALL THE FOG HAS BURNED OFF AROUND THE AREA. LEFT IN MENTION OF
LATE MORNING THROUGH EARLY EVENING SHOWER AND STORM CHANCES AS THE
LATEST DATA FROM THE SREF AND HRRR BOTH STILL SUPPORTING IT. WILL
MONITOR THAT PART OF THE FORECAST OVER THE NEXT FEW HOURS TO
DETERMINE IF ANOTHER UPDATE WILL BE NEEDED.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 326 AM EDT FRI AUG 1 2014
THE MODELS START OUT IN GOOD AGREEMENT WITH AN UPPER LOW NEAR HUDSONS
BAY. THE KEY FEATURE IS A SHORT WAVE MOVING DOWN THE BACK SIDE OF THE
UPPER TROUGH. THIS SHORT WAVE IS FORECAST TO INTENSIFY AS IT DIPS
SOUTH INTO THE CENTRAL US. BY TONIGHT...THE SHORT WAVE WILL EXTEND
FROM LAKE SUPERIOR SOUTH ACROSS CENTRAL ILLINOIS INTO LOUISIANA. WITH
THIS SYNOPTIC PATTERN...THE COLD FRONT IS WELL THE SOUTH OF THE AREA
ALONG THE GULF COAST AND THE BLOCKING RIDGE OUT WEST IS BLOCKING ANY
FRONTS FROM MOVING INTO THE AREA. THE SHORT WAVE TROUGH AXIS IS FORECAST
TO MOVE ACROSS EASTERN KENTUCKY ON SATURDAY EVENING. THE MODELS ARE
IN GOOD AGREEMENT WITH THE TIMING OF THE TROUGH PASSAGE. THE MAIN
DRIVER OF THE WEATHER WILL BE THE GENERAL INSTABILITY ASSOCIATED WITH
THE UPPER LOW AND THEN THE PASSING OF THE UPPER TROUGH AXIS. THERE
HAS BEEN SOME MID LEVEL CAPPING THAT HAS HELD DOWN ANY CLOUDS FROM
GROWING BIG ENOUGH TO PRODUCE RAIN SHOWERS. AS THE TROUGH NEARS...THE
MID LEVEL CAPPING WILL BEGIN TO ERODE AND THE NET RESULT IS THAT SOME
ISOLATED TO SCATTERED THUNDERSTORMS AND SHOWERS WILL BE ABLE TO FORM.
THERE ARE ENOUGH DIFFERENCES IN HOW THE MODELS HANDLE THIS
SYSTEM...THAT CONFIDENCE IS LOWER THAN NORMAL WITH HOW WIDESPREAD
THE PRECIPITATION WILL BE. THERE COULD BE A SCENARIO WHERE THE ENERGY
WILL PASS TO THE NORTH AND SOUTH OF THE AREA AND THERE WILL BE
MINIMAL CONVECTION OF EASTERN KENTUCKY. THE PROBABILITY OF
PRECIPITATION IS A BIT LOWER THAN WHAT THE PREVIOUS FORECASTS HAD.
FOR TEMPERATURES USED A BLEND OF THE NAM AND GFS MOS AND THEN MADE
SOME ADJUSTMENTS FOR TERRAIN EFFECTS.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 AM EDT FRI AUG 1 2014
THE PERSISTENT TROUGH OVER THE EASTERN U.S. WILL DEAMPLIFY A BIT
THROUGH THE LONG TERM PERIOD BUT REMAIN PRETTY MUCH IN PLACE IN THE
MEANS. A PASSING SHORTWAVE WILL KEEP THE THREAT OF SHOWERS/STORMS IN
OUR FORECAST FOR SATURDAY NIGHT AND SUNDAY. WEAK HIGH PRESSURE WILL
THEN BUILD INTO THE REGION BY EARLY NEXT WEEK AND MOST LOCATIONS
SHOULD BE DRY AS A RESULT WITH THE EXCEPTION OF ALONG THE VIRGINIA
BORDER WHERE PROXIMITY TO DEEPER MOISTURE JUST TO OUR SOUTHEAST MAY
ALLOW A FEW SHOWERS/STORMS TO FIRE WITH DAYTIME HEATING MONDAY
AFTERNOON. A COLD FRONT WILL SAG SOUTHWARD SLOWLY THROUGH TIME INTO
THE OHIO VALLEY. MOST MODELS KEEP THIS FRONT WELL TO OUR NORTH
THROUGH MIDWEEK...BUT THE 01/00Z ECMWF SHIFTED COURSE AND IS AN
OUTLIER DROPPING IT ALL THE WAY THROUGH OUR AREA. WILL CONTINUE WITH
A DRY FORECAST FOR NOW THROUGH WEDNESDAY BEFORE RAIN CHANCES
INCREASE AGAIN ON THURSDAY AS THE FRONT APPROACHES. TEMPERATURES
WILL MODERATE SLOWLY THROUGH TIME BUT ONLY UP TO NORMAL LEVELS FOR
EARLY AUGUST BY WEDNESDAY AND THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 800 AM EDT FRI AUG 1 2014
EXPECTING VFR CONDITIONS THROUGH THE NEAR DAWN TOMORROW AT THE TAF
STATIONS...HOWEVER THERE WILL BE SOME VLIFR IN SOME OF THE
VALLEYS...ESPECIALLY NEAR RIVERS AND STREAMS. THE FOG SHOULD BE
BURNING OFF BY 13Z. THE MIGHT BE SOME TEMPO IFR AS THE FOG LIFTS OUT
OF THE VALLEYS...SOME OF THE STRATUS MAY MOVE ACROSS THE AIRFIELD. LOOKING
FOR SOME ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS MOVING
ACROSS THE AREA FROM THE MID MORNING THROUGH AROUND 6Z. THE TIMING IS
TOO UNCERTAIN TO PUT IN ANY TEMPO GROUPS AT THIS TIME...HOWEVER DO
EXPECT SOME MVFR CONDITIONS UNDER THE STORMS IF THEY MOVE ACROSS A TAF
STATION. FOG IS MORE LIKELY TOMORROW DUE TO THE RAIN WHICH IS
EXPECTED TODAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AR
SHORT TERM...JJ
LONG TERM...ABE
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS PADUCAH KY
644 AM CDT Fri Aug 1 2014
.UPDATE...
Issued at 644 AM CDT FRI AUG 1 2014
The AVIATION section has been updated for the 12Z TAF issuance.
&&
.SHORT TERM...(Today through Sunday)
Issued at 305 AM CDT FRI AUG 1 2014
Will be monitoring the patchy and shallow dense fog across much of
the area again this morning. See no reason why it wouldn`t be
similar to yesterday`s development.
A sharper mid/upper level trough will develop within the broad
cyclonic flow over the region through tonight, but the 00Z models
are a bit weaker and farther east with it compared to yesterday`s
runs. It will push just east of the area by Saturday evening.
In the low-levels, weak warm advection is noted within the KPAH
VAD wind profile, but the surface pressure pattern is very flat. A
minor push of surface high pressure into the area is expected in
the wake of the upper trough late Saturday into Sunday.
The weak warm advection over southeast Missouri may result in some
isolated shower activity this morning. The NAM soundings in western
portions of southeast Missouri indicate a shallow layer of
instability based around 7kft, and the HRRR develops showers
northward into that area from the Boot Heel region and northeast
Arkansas through the morning. The soundings dry up by 18Z, but as
the mid/upper trough develops southward toward our region, a small
chance of deep convection exists across northern portions of
southern Illinois in the late afternoon and possibly into the
early evening. If a storm develops it should be short-lived and
rather weak.
With the upper trough over the eastern half of the region
Saturday, isolated diurnal showers and thunderstorms can be
expected generally along and east of the Mississippi River. Once
again any storms should be short-lived and rather weak.
As for temperatures, the consensus of rather tightly grouped guidance
looks pretty good through the period.
.LONG TERM...(Sunday Night through Friday Night)
Issued at 305 AM CDT FRI AUG 1 2014
High Pressure aloft dominates the WFO PAH forecast area through 12z
Thursday. effectively suppressing convection across the region.
Between 18z Wednesday and 18z Thursday, the latest 00z Friday medium
range model guidance begin to differ sharply in the position of a
deepening shortwave in the Upper Midwest/Northern Plains region.
This significantly impacts the rapidly evolving baroclinic zone to
the northwest of the WFO PAH forecast area. The ECMWF sets up a warm
advection flow with convection being developed along a warm front
developing over the Tri-State region (Southwest IN, Northwest
Kentucky, Southeast Illinois. The GFS keeps the WFO PAH forecast
area in the warm sector ahead of the impressed warm and cold fronts.
By Thursday, the movement and deepening of the Upper
Midwest/Northern Plains low continues to differ sharply with the
GFS/ECMWF/NAM guidance in locations and to a lesser degree timing of
upstream convection. Regardless of the latest solution, slowed down
the onset of convection into the area into Thursday.
Beyond Thursday, the east-southeast movement and deepening of the
Upper Midwest/Northern Plains shortwave transitions into an upper Low
over the Great Lakes by late Friday night. Although there is some
initial concern on the timing of the precipitation into the WFO PAH
CWA, this becomes a moot point Thursday into Friday as the
baroclinic zone becomes stretched across the area, prolonging rain
chances across the area. In fact, several of the recent model runs
are consistent in keeping higher than normal PoPs/Weather in place
during this time period.
Therefore, PoPs and Weather have been included for the period from
next Thursday into Friday. All other forecast changes minor, with
the exception of those sensible weather elements impacted by the
forecast convection.
&&
.AVIATION...
Issued at 644 AM CDT FRI AUG 1 2014
Weak flow regime continues over the region through the period. Any
convection that develops today should not impact the TAF sites.
Guidance continues to indicate scattered to broken clouds between
5kft and 12kft through the period. The only concern to aviation
will be fog once again. This morning`s fog should lift to VFR in
the first hour or two of the forecast. Tonight, some more
development seems likely at KCGI, but not at the other sites. Will
keep KCGI at MVFR late tonight, but will not be surprised if it
tries to tank again.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
UPDATE...DRS
SHORT TERM...DRS
LONG TERM...Smith
AVIATION...DRS
AREA FORECAST DISCUSSION
NWS PADUCAH KY
306 AM CDT Fri Aug 1 2014
.SHORT TERM...(Today through Sunday)
Issued at 305 AM CDT FRI AUG 1 2014
Will be monitoring the patchy and shallow dense fog across much of
the area again this morning. See no reason why it wouldn`t be
similar to yesterday`s development.
A sharper mid/upper level trough will develop within the broad
cyclonic flow over the region through tonight, but the 00Z models
are a bit weaker and farther east with it compared to yesterday`s
runs. It will push just east of the area by Saturday evening.
In the low-levels, weak warm advection is noted within the KPAH
VAD wind profile, but the surface pressure pattern is very flat. A
minor push of surface high pressure into the area is expected in
the wake of the upper trough late Saturday into Sunday.
The weak warm advection over southeast Missouri may result in some
isolated shower activity this morning. The NAM soundings in western
portions of southeast Missouri indicate a shallow layer of
instability based around 7kft, and the HRRR develops showers
northward into that area from the Boot Heel region and northeast
Arkansas through the morning. The soundings dry up by 18Z, but as
the mid/upper trough develops southward toward our region, a small
chance of deep convection exists across northern portions of
southern Illinois in the late afternoon and possibly into the
early evening. If a storm develops it should be short-lived and
rather weak.
With the upper trough over the eastern half of the region
Saturday, isolated diurnal showers and thunderstorms can be
expected generally along and east of the Mississippi River. Once
again any storms should be short-lived and rather weak.
As for temperatures, the consensus of rather tightly grouped guidance
looks pretty good through the period.
.LONG TERM...(Sunday Night through Friday Night)
Issued at 305 AM CDT FRI AUG 1 2014
High Pressure aloft dominates the WFO PAH forecast area through 12z
Thursday. effectively suppressing convection across the region.
Between 18z Wednesday and 18z Thursday, the latest 00z Friday medium
range model guidance begin to differ sharply in the position of a
deepening shortwave in the Upper Midwest/Northern Plains region.
This significantly impacts the rapidly evolving baroclinic zone to
the northwest of the WFO PAH forecast area. The ECMWF sets up a warm
advection flow with convection being developed along a warm front
developing over the Tri-State region (Southwest IN, Northwest
Kentucky, Southeast Illinois. The GFS keeps the WFO PAH forecast
area in the warm sector ahead of the impressed warm and cold fronts.
By Thursday, the movement and deepening of the Upper
Midwest/Northern Plains low continues to differ sharply with the
GFS/ECMWF/NAM guidance in locations and to a lesser degree timing of
upstream convection. Regardless of the latest solution, slowed down
the onset of convection into the area into Thursday.
Beyond Thursday, the east-southeast movement and deepening of the
Upper Midwest/Northern Plains shortwave transitions into an upper Low
over the Great Lakes by late Friday night. Although there is some
initial concern on the timing of the precipitation into the WFO PAH
CWA, this becomes a moot point Thursday into Friday as the
baroclinic zone becomes stretched across the area, prolonging rain
chances across the area. In fact, several of the recent model runs
are consistent in keeping higher than normal PoPs/Weather in place
during this time period.
Therefore, PoPs and Weather have been included for the period from
next Thursday into Friday. All other forecast changes minor, with
the exception of those sensible weather elements impacted by the
forecast convection.
&&
.AVIATION...
Issued at 632 PM CDT THU JUL 31 2014
Conditions will be primarily VFR over the next 24 hours. Patchy fog
may restrict visibilities late tonight, especially at KCGI and KPAH.
The presence of an upper level trough will keep a scattering of VFR
clouds around through the period. Winds will be light and variable
tonight then northeast around 5 knots Friday.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...DRS
LONG TERM...Smith
AREA FORECAST DISCUSSION
NWS JACKSON KY
156 AM EDT FRI AUG 1 2014
.UPDATE...
ISSUED AT 156 AM EDT FRI AUG 1 2014
UPDATED THE FORECAST TO SLOW DOWN THE ONSET OF PRECIPITATION MOVING
IN FROM THE SOUTH. IT MAY NEED SOME FURTHER SLOWING DOWN BASED ON THE
CURRENT RADAR. ALSO MADE SOME UPDATES TO THE FIRST THREE PERIODS
BASED ON THE NEWEST MODEL DATA AVAILABLE. THE UNCERTAINTY HAS REALLY
INCREASED IN THE SHORT TERM DUE TO THE RUN TO RUN INCONSISTENCIES AND
THE MODEL DIFFERENCES. WILL WAIT AND SEE THE NEW ECMWF BEFORE
FINALIZING THE SHORT TERM FORECAST.
UPDATE ISSUED AT 1055 PM EDT THU JUL 31 2014
SEEING A LITTLE CONVECTION IN OUR FAR SOUTHEAST...BEING THE RESULT OF
SOME SFC/BOUNDARY LAYER OF CONVERGENCE. APPEARS TO BE SOME UPSLOPE
COMPONENT ON THE SOUTH SIDE OF BLACK MOUNTAIN AS WELL WHICH HAS BEEN
STRONG ENOUGH TO PRODUCE A COUPLE OF THUNDERSTORM CELLS RIGHT ALONG
OR JUST SOUTH OF THE KY/VA STATE LINE. THE VAST MAJORITY OF THE
ACTIVITY HAS BEEN OUTSIDE OF OUR CWA...AND THE OCCASIONAL CELL THAT
MANAGES TO MOVE INTO KY WEAKENS QUICKLY. BEING OF SUCH AN ISOLD
NATURE...DECIDED TO LEAVE ANY MENTION OF THUNDER OUT OF THE GRIDS AND
ZONES AND TO ADDRESS THE POTENTIAL WITH A GRAPHICAL NOWCAST PRODUCT.
ALSO MADE A FEW MINOR ADJUSTMENTS TO OVERNIGHT LOWS AS THIN CI CANOPY
HAS DONE LITTLE TO PREVENT A RAPID DROP OFF OF TEMPS THROUGH THE
EVENING...WHICH HAS BEEN MORE DRAMATIC IN THE NORTH AND EAST.
HOWEVER...MID LEVEL CLOUDS WILL BE ON THE INCREASE AND ARE BEING
PICKED UP NOW AT A FEW OF OUR SOUTHERN STATIONS. INCREASE IN CLOUDS
SHOULD HELP KEEP OVERNIGHT LOWS FROM BOTTOMING OUT TOO MUCH AND MAY
EVEN TEND TO CAUSE A BIT OF REBOUNDING WHERE CEILINGS MATERIALIZE.
OTHERWISE UPDATED THE ZONE PACKAGE TO FRESHEN UP WORDING.
UPDATE ISSUED AT 836 PM EDT THU JUL 31 2014
FORECAST IS IN VERY GOOD SHAPE THIS EVENING. MADE SOME MINOR TWEAKS
TO THE GRIDS FOR LATEST HOURLY OBS. WILL HOLD OFF ON ANY CHANGES TO
THE ZONES UNTIL NEXT UPDATE...WHEN AT A MINIMUM WORDING WILL BE
FRESHENED UP TO REMOVE EVENING REFERENCES.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 355 PM EDT THU JUL 31 2014
19Z SFC ANALYSIS SHOWS A WEAK AREA OF HIGH PRESSURE THROUGH KENTUCKY
TO THE MID ATLANTIC STATES. TO THE SOUTH...A COUPLE OF WAVES OF LOW
PRESSURE ARE TAKING SHAPE...ONE OVER THE SOUTHERN APPALACHIANS AND
ANOTHER NEAR BAYOU COUNTRY IN LOUISIANA. ON RADAR...A FEW SHOWERS
HAVE DEVELOPED OVER THE SOUTHERN APPALACHIANS...BUT SO FAR EAST
KENTUCKY HAS BEEN CLEAR. ON SATELLITE...THE EARLIER LOW CLOUDS BROKE
UP IN THE SOUTH AND A DECENT CU FIELD HAS FORMED OVER THE ENTIRE CWA.
THESE CLOUDS HAVE NOT HAMPERED TEMPERATURES MUCH...THOUGH...AS THEY
HAVE MADE IT TO THE UPPER 70S AND LOW 80S...SO FAR. WITH THE RETURN
OF WARMER AFTERNOON WEATHER...THE DEW POINTS HAVE ALSO CREPT UP SO
THAT THEY ARE IN THE MID TO UPPER 50S...AND ALL THE WHILE THE WINDS
REMAIN LIGHT AND VARIABLE.
THE MODELS ARE IN GOOD AGREEMENT ALOFT AS THE UPPER LOW THAT HAS
DOMINATED THE WEATHER OVER THE OHIO VALLEY WILL RETREAT TO THE NORTH
THROUGH THE SHORT TERM ALLOWING FOR MORE ENERGY TO MOVE ACROSS THE
TENNESSEE VALLEY INTO THE DAY FRIDAY. MORE SIGNIFICANTLY...THOUGH...A
MID LEVEL WAVE WILL DROP SOUTHEAST THROUGH THE PLAINS AND INTO THE
MID MISSISSIPPI VALLEY FRIDAY NIGHT...STARTING TO CARVE OUT ANOTHER
NODE OF THE EASTERN TROUGH THROUGH THE WESTERN OHIO VALLEY BY
SATURDAY MORNING. THE ECMWF AND GEM ARE A BIT QUICKER AND FURTHER
EAST WITH THIS DEVELOPMENT THAN THE NAM AND GFS. FOR NOW...WILL
FOLLOW A GENERAL MODEL BLEND WITH SOME LEANING ON THE SPECIFICS FROM
THE HRRR AND NAM12.
SENSIBLE WEATHER WILL FEATURE A MILDER NIGHT THROUGH EAST KENTUCKY
DUE TO AN INCREASE IN CLOUD COVER AND HIGHER DEW POINTS. THIS WILL
ALSO LIKELY LIMIT THE FOG DEVELOPMENT TO JUST THE DEEPEST VALLEYS. IN
ADDITION TO THE CLOUDS...A FEW SHOWERS WILL BE POSSIBLE LATER
TONIGHT ACROSS THE EASTERN PARTS OF THE AREA WITH MORE SUBSTANTIAL
RAINS EXPECTED LATER FRIDAY...PRIMARILY IN THE FAR EAST. THUNDER WILL
BE A POSSIBILITY LATER FRIDAY AND INTO THE NIGHT AS A COUPLE OF SFC
WAVES PASS THROUGH THE AREA. HAVE GONE WITH JUST ISOLATED THUNDER
CHANCES...THOUGH...AS THE INSTABILITY WILL BE LESS THEN OPTIMAL FOR
WIDESPREAD STORMS INTO SATURDAY MORNING. THE CLOUDS TONIGHT AND AGAIN
FRIDAY NIGHT WILL ALSO LIMIT THE RIDGE AND VALLEY TEMPERATURE
DIFFERENCES SO HAVE MINIMIZED THESE. LIKEWISE...TEMPS WILL BE
TEMPERED BY THE CLOUDS AND PCPN DURING THE DAY FRIDAY.
STARTED WITH THE BC/CONSSHORT FOR THE T...TD...AND WIND GRIDS
THROUGH THE FIRST 24 HOURS AND THEN PLUGGED IN THE CONSALL SUITE FOR
THE REMAINDER OF THE SHORT TERM FORECAST. MADE SOME SMALL ADJUSTMENTS
TO LOW TEMPERATURES TONIGHT AND FRIDAY NIGHT FOR SOME MINOR RIDGE
TO VALLEY SPLITS. AS FOR POPS...ENDED UP CLOSER TO THE MAV NUMBERS
FROM LATER TONIGHT THROUGH SATURDAY MORNING RATHER THAN THE HIGH MET
ONES TONIGHT AND LOW VALUES FOR FRIDAY.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 300 PM EDT THU JUL 31 2014
GENERALLY SPEAKING OUR WEATHER WILL BE UNDER THE INFLUENCE OF A MEAN
EASTERN CONUS TROUGH THROUGH THE PERIOD. EXCEPTION WILL BE A SHORT
WINDOW OF TIME...DYS 6/7...WED/THUR OF NEXT WEEK WHERE FLOW ALOFT
WILL BE ANTICYCLONIC TO ZONAL IN NATURE. THIS PERIOD OF SHORT WAVE
RIDGING WILL PROVIDE OUR WARMEST WEATHER OF THE EXTENDED...ALLOWING
TEMPS TO RISE TO MORE NORMAL SUMMERTIME LEVELS AND HIGHER DURING THE
LATTER HALF OF THE FORECAST. MODELS ARE SHOWING A DECENT ENOUGH
CONSENSUS IN SOLUTIONS WHERE DEEP TROUGH OVER THE EASTERN CONUS
GRADUALLY LIFTS OUT OF THE AREA BY LATE DY5...TUE. ADDITIONAL ENERGY
DROPS OUT OF CANADA BY LATE WEEK...JUST BEYOND THE EXTENDED FORECAST
WINDOW...EFFECTIVELY CARVING OUT A NEW EASTERN CONUS TROUGH.
HOWEVER...CONSIDERABLE DISAGREEMENT EXISTS BETWEEN THE GFS AND A
MORE CONSISTENT ECMWF WITH RESPECT TO AMPLITUDE/STRUCTURE OF THE
LATTER TROUGH. ECMWF ACTUALLY DEVELOPS A STACKED UPPER LEVEL LOW
OVER THE SOUTHERN OHIO VALLEY REGION WHILE THE GFS ADVERTISES A
LOWER AMPLITUDE TROUGH WITH ITS PARENT LOW NORTH OF THE GREAT LAKES.
FOR SENSIBLE WEATHER...ENERGY ROUNDING THE BASE OF DEEP EASTERN
CONUS TROUGH WILL KEEP A THREAT OF MAINLY AFTERNOON AND EVENING
SHOWERS AND THUNDERSTORMS IN THE FORECAST THROUGH ROUGHLY THE FIRST
30 HOURS OF THE EXTENDED. THEN WE WILL SEE WARMER AND DRYER WEATHER
THROUGH THE MID TERM. POTENTIAL FOR RAIN RETURNS AT THE END OF THE
FORECAST PERIOD WITH APPROACH OF ANOTHER SYSTEM FROM THE WEST BY
DY7...THU. WE CAN EXPECT A MODERATION OF TEMPERATURES THROUGH THE
EXTENDED...PEAKING OUT CLOSE TO 90 FOR AFTERNOON HIGHS BY NEXT
WED...AND POSSIBLY THURSDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 156 AM EDT FRI AUG 1 2014
IN GENERAL EXPECTING VFR CONDITIONS THROUGH THE FORECAST PERIOD AT
THE TAF STATIONS...HOWEVER THERE WILL BE SOME VLIFR IN SOME OF THE
VALLEYS...ESPECIALLY NEAR RIVER AND STREAMS. THE ONLY TAF STATION
THAT IS IN DANGER OF IFR OR LOWER IS SME. THEY IS A ZERO SPREAD
BETWEEN TEMPERATURE AND DEWPOINT ALREADY...SO PRETTY MUCH WENT WITH A
PERSISTENCE FORECAST. AT THE OTHER TAF STATIONS...THE ONLY CONCERN IS
SOME STRATUS MOVING ACROSS THE TAF STATIONS AS THE FOG LIFTS OUT OF
THE VALLEY. LOOKING FOR SOME ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS MOVING ACROSS THE AREA FROM THE MID MORNING THROUGH THE
END OF THE TAF PERIOD. THE TIMING IS TOO UNCERTAIN TO PUT IN ANY
TEMPO GROUPS AT THIS TIME...HOWEVER DO EXPECT SOME MVFR CONDITIONS
UNDER THE STORMS IF THE MOVE ACROSS A TAF STATION.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJ
SHORT TERM...GREIF
LONG TERM...RAY
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
950 PM EDT SAT AUG 2 2014
.SYNOPSIS...
A FRONTAL BOUNDARY REMAINS NEARLY STATIONARY ALONG THE MID ATLANTIC
COAST THROUGH MONDAY. AREAS OF LOW PRESSURE WILL TRACK NORTHEAST
ALONG THIS BOUNDARY...KEEPING UNSETTLED CONDITIONS IN PLACE INTO
EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
LATEST ANALYSIS SHOWING SFC TROUGH PERSISTING ALONG THE COASTAL
AREAS WITH WEAK HIGH PRESSURE CENTERED OFF NEW ENGLAND NOSING SSW
INTO THE MID ATLC. THIS IN SITU CAD SETUP MAKING FOR AN
ANOMALOUSLY COOL EARLY AUGUST WX ACRS THE REGION...TEMPERATURES
TDA GENLY NO BETTER THAN THE 70S.
WILL HAVE HI PROB FOR SHRAS OVRNGT ERN PORTION (60-80%)...NOT
RULING OUT LOCALLY HEAVY RA...BUT THAT APPEARS TO BE A LO PROB
ATTM (UNLESS PAST COUPLE RUC RUNS TURNS OUT RIGHT W/
DEVELOPING/MOVING AREA OF MDT/HEAVY RA NE NR THE CST OVRNGT).
HANGING ONTO 20% W. LO TEMPS FM THE M60S TO ARND 70F.
MAIN CONCERN OVER THE NEXT 24 HRS CONTINUES TO BE HEAVY
RAINFALL...AND ACRS MOST OF SE VA/NE NC PRECIP AMOUNTS HAVE
AVERAGED 2-3" WITH LOCAL AMOUNTS OVER 4" RECEIVED. WHILE PRECIP
THUS FAR TODAY HAS BEEN SOMEWHAT SPOTTY AND SPORADIC...THINK THERE
ARE ENOUGH ATMOSPHERIC INGREDIENTS IN PLACE LATER TONIGHT TO
JUSTIFY A FLOOD WATCH. PER COLLABORATION W/ NEIGHBORING OFFICES
WENT FLOOD WATCH RATHER THAN FLASH FLOOD WATCH...ALTHOUGH SOME
LOCALIZED FLASH FLOODING CAN`T BE RULED OUT LT TNGT OR SUN ESP IN
URBAN AREAS.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
ON SUNDAY...LITTLE CHANGE SEEN IN OVERALL PATTERN WITH YET ANOTHER
S/W ENHANCING RAINFALL PTNTL ALONG COASTAL SECTIONS...BUT AREAS
FARTHER INLAND MAY TEND TO SEE MORE BREAKS AND LESS COVERAGE OF
PRECIP AS FORCING IS EXPECTED TO REMAIN FARTHER EAST THAN PAST 2
DAYS. A BIT WARMER INLAND AS PCPN SHOULD BECOME A BIT MORE SPOTTY
IN NATURE. HIGHS U70S/LOWER 80S EAST TO LWR/MID 80S ALONG/WEST OF
I-95.
LOWS SUN NIGHT 65-70 F WITH HIGHEST PCPN CHCS ALONG THE
COAST...HAVE SCALED BACK TO ONLY 20-30% CHC POPS NW 1/2 OF THE CWA
AFTER MIDNIGHT.
FOR MON/TUE...GFS/ECMWF DIFFER AS TO EXTENT OF SFC TROUGHING
REMAINING ALONG THE COAST...LIKELY DUE TO UNCERTAINTIES WITH
RESPECT TO WHERE TC BERTHA WILL BE LOCATED. WILL RETAIN CHC POPS
ALL AREAS MON BUT WILL STILL FOCUS HIGHEST POPS ALONG THE COAST.
ON TUE...A LOW CONFIDENCE FORECAST AS LATEST ECMWF IS WETTER AS
TROUGH STRENGTHENS AND PUSHES DEEPER MOISTURE BACK N INTO THE MID
ATLC WHILE GFS IS GENLY DRY. WILL RETAIN SLIGHT CHC TO LOW CHC
POPS MOST AREAS WITH HIGHS MON MAINLY IN THE MID-UPPER 80S AND
HIGHS TUE 85-90 F.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
A BRIEF DRY PERIOD IS EXPECTED TUE NIGHT INTO EARLY WED AS THE MID
ATLANTIC REGION SITS BTWN THE DEPARTING FRONTAL BOUNDARY AND ANOTHER
APPROACHING COLD FRONT FROM THE NW. THIS FRONT IS EXPECTED TO CROSS
THE AREA LATE DAY WED INTO THU MORNING...AND THEN GET STRETCHED
ACROSS THE CAROLINAS LATER THU INTO FRI. SCATTERED
SHOWERS/THUNDERSTORMS WILL BE POSSIBLE AREAWIDE ON WED...THEN PRECIP
GETS SHUNTED SOUTH ALONG THE VA/NC BORDER AND POINTS SWD FOR
THU/FRI. HIGH PRESSURE BUILDS BACK INTO THE REGION FROM THE NW LATE
FRI INTO NEXT WEEKEND. HIGH TEMPERATURES WILL BE NEAR NORMAL WED
(UPPER 80S TO LOWER 90S) AND THEN COOL UP TO 5 DEGREES BELOW NORMAL
FOR THU-SAT (GENERALLY IN THE 80S). LOW TEMPERATURES TUE/WED NIGHTS
WILL AVERAGE OUT IN THE UPPER 60S TO LOWER 70S AND THEN EXPERIENCE A
SLIGHT COOL DOWN WITH LOWS GENERALLY IN THE 60S THU/FRI NIGHTS.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
WEAK COASTAL TROF HAS MOVED TO KECG AND WILL BE SLOW TO MOVE WEST.
CURRENTLY SHOWERS CONFINED TO THE EASTERN PORTION OF THE AKQ
CWA...MOVING SLOWLY TO THE NNE. NEXT SHORTWAVE INTERACTING WITH
BOUNDARY OVER SOUTH CAROLINA WILL BRING MORE SHOWERS NORTH
STARTING AT KECG BEFORE MIDNIGHT AND GRADUALLY MOVING NORTH ACROSS
THE SITES. NOT SURE HOW MUCH WILL GET WEST TO KRIC. COULD HAVE AN
ISOLATED TSTM NEAR THE BOUNDARY TONIGHT. WILL AGAIN BRING BACK IFR
CIGS TO ALL SITES EXCEPT KECG BY 06Z WITH KECG BEING ON THE EAST
SIDE OF THE BOUNDARY THEY COULD STAY MVFR TONIGHT. ON SUNDAY
PRECIP MOVES TOWARD THE COAST AND CIGS RISE TO MVFR ALL LOCATIONS.
PRECIPITATION COVERAGE MOVES MORE ALONG THE COAST BY SUNDAY NIGHT
AND MAINLY OVER NORTHEAST NORTH CAROLINA BY MONDAY. SHOULD SEE ALL
BUT KECG BECOME VFR BY MONDAY AND EVEN KECG BY MONDAY.
&&
.MARINE...
A FRONTAL BOUNDARY WILL REMAIN INVOF THE MID-ATLANTIC COAST THROUGH
THE WEEKEND. NO FLAGS ARE EXPECTED AS WIND SPEEDS REMAIN GENERALLY
E-SE AOB 15 KT AND SEAS/WAVES SHOULD REMAIN BELOW 5FT/4FT.
NEVERTHELESS...PERSISTENT ONSHORE FLOW SHOULD KEEP SEAS AROUND 3
FT...WITH OCCASIONAL 4 FT SEAS OUT NEAR 20NM. WAVES IN THE BAY WILL
AVERAGE 1-2 FT. THE FRONT GETS PULLED OFFSHORE BY TROPICAL STORM
BERTHA AS IT STAYS WELL EAST OF THE OUTER BANKS...AND ALSO AS HIGH
PRESSURE BUILDS INTO THE REGION FROM THE NW. SOME LONG PERIOD SWELL
COULD ENCROACH THE AREA DEPENDING ON THE STRENGTH/TRACK OF TROPICAL
STORM BERTHA. CURRENT 02/1200Z WAVEWATCH GUIDANCE NOW ONLY BRINGS 3
FT SWELL OUT NEAR 20 NM TUESDAY AND WEDNESDAY OF NEXT WEEK...WITH 4
FT SWELL POSSIBLE BEYOND 20 NM FROM THE OUTER BANKS.
ANOTHER COLD FRONT APPROACHES FROM THE NW WEDNESDAY AND MOVES TWD
THE VA/NC BORDER BY THURSDAY. OVERALL SUB-SCA CONDITIONS ARE
EXPECTED TO PREVAIL TONIGHT THROUGH NEXT WEEK WITH THE EXCEPTION OF
MINOR AFFECTS FELT BY THE PASSING OF TROPICAL STORM BERTHA.
&&
.HYDROLOGY...
PERIODIC RAINFALL ALONG A SLOW-MOVING FRONTAL BOUNDARY WILL
CONTINUE TO BRING ACCUMULATING PRECIPITATION TO THE REGION TODAY
THROUGH MONDAY. HIGHEST ACCUMULATIONS FOCUSED OVER NE NC AND SE
VA WITH ADDNTL QPF AMTS BTWN 1.5-2.5 INCHES (LCLLY HIGHER IN
TRAINING ECHOES) PRIMARILY OVER THE NEXT 24 HRS.
RAISED FLOOD WATCH IN AREAS THAT HAVE GENLY RECEIVED 2-4" OVER PAST
24 HRS WHERE ADDITIONAL SIGNIFICANT RAINFALL AMOUNTS MAY RESULT IN
FLOODING OF URBAN AREAS...AREAS OF POOR DRAINAGE...LOW LYING
AREAS...AND TO RISES OF SMALL STREAMS/CREEKS. WILL CONTINUE TO
HIGHLIGHT LOCALLY HEAVY RAINFALL POTENTIAL FOR AREAS NOT IN THE
WATCH IN THE HWO.
&&
.CLIMATE...
COOL DAYTIME TEMPERATURES FOR EARLY AUGUST...COMING CLOSE TO
CHALLENGING RECORDS. FOR REFERENCE...THE RECORD LOW MAXIMUM
TEMPERATURES FOR TODAY/AUGUST 2ND:
RICHMOND....74 F (1903).
NORFOLK.....74 F (1916).
SALISBURY...74 F (1959).
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK THROUGH SUNDAY EVENING FOR MDZ025.
NC...FLOOD WATCH THROUGH SUNDAY EVENING FOR NCZ013>017-030>032-102.
MODERATE RIP CURRENT RISK THROUGH SUNDAY EVENING FOR NCZ102.
VA...FLOOD WATCH THROUGH SUNDAY EVENING FOR VAZ095>100.
MODERATE RIP CURRENT RISK THROUGH SUNDAY EVENING FOR
VAZ098>100.
MARINE...NONE.
&&
$$
SYNOPSIS...ALB/LKB
NEAR TERM...ALB/LKB
SHORT TERM...LKB/MPR
LONG TERM...BMD
AVIATION...DAP/JAB
MARINE...BMD
HYDROLOGY...AKQ
CLIMATE...AKQ
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
830 PM CDT SAT AUG 2 2014
.SYNOPSIS...
ISSUED AT 320 PM CDT SAT AUG 2 2014
THE WESTERN CONUS RIDGE/EASTERN CONUS TROUGH PATTERN CONTINUES IN
THE UPPER LEVELS WITH THE CENTRAL PLAINS UNDER THE INFLUENCE OF
NORTHWEST FLOW WITH WEAK SHORTWAVES PERIODICALLY MOVING OVER THE
RIDGE AND ACROSS THE AREA AS THEY DIVE INTO THE TROUGH. AT
19Z...NOTING A SHORTWAVE TROUGH MOVING INTO NORTHERN SOUTH
DAKOTA...WITH ANOTHER OVER SOUTHERN WYOMING. 02.12Z SOUNDINGS SHOWED
700MB TEMPERATURES OF 9C AND 8C AT KUNR AND KLBF RESPECTIVELY...WITH
5C AND 6C AT KABR AND KOAX. THIS WOULD INDICATE THAT ALTHOUGH THE
AREA IS UNDER NORTHWEST FLOW...THE WARM AIR ALOFT UNDER THE RIDGE
CONTINUES TO STAY IN PLACE ACROSS THE WESTERN PLAINS. HOWEVER...THIS
AIR IS NOT WARM ENOUGH TO CAP THE BOUNDARY LAYER. AT THE
SURFACE...LOW PRESSURE WAS SITUATED OVER SOUTH CENTRAL SOUTH
DAKOTA...JUST NORTH AND EAST OF KVTN WITH A WEAK TROUGH OF LOW
PRESSURE EXTENDING SOUTH THEN WEST /TO AROUND KBBW THROUGH KLBF AND
KOGA. STRONG HEATING AT THE SURFACE WITH HIGHS IN THE UPPER 80S AND
LOW 90S HAS CREATED DEEP MIXING UP TO 600MB AND WITH STEEP LAPSE
RATES CONVECTION HAS BEGUN TO DEVELOP ACROSS THE AREA WHERE
CONVERGENT BOUNDARIES EXIST. MU CAPES ARE 1500 TO 2000 J/KG BUT
THERE IS VERY LITTLE SHEAR OVER ONGOING CONVECTION SO ACTIVITY HAS
BEEN VERY UNORGANIZED THUS FAR THIS AFTERNOON.
&&
.UPDATE...
ISSUED AT 828 PM CDT SAT AUG 2 2014
THUNDERSTORMS IN SOUTH CENTRAL SOUTH DAKOTA ARE PRODUCING LARGE
HAIL...SO WE HAVE UPDATED THE FORECAST FOR NORTH CENTRAL NEBRASKA
TO INCLUDE THE POSSIBILITY OF SEVERE THUNDERSTORMS.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 320 PM CDT SAT AUG 2 2014
SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH THE AFTERNOON AND
INTO THIS EVENING UNTIL LOSS OF DAYTIME HEATING STABILIZES THE
BOUNDARY LAYER AND CUTS OFF THE ENERGY INTO THE STORMS. THE SURFACE
LOW OVER SOUTH DAKOTA WILL SLOWLY MOVE SOUTHEAST THROUGH THE EVENING
WITH THE PRECIPITATION GENERALLY STAYING ALONG AND SOUTH OF AN ARC
FROM THE LOW TO KTIF TO KAIA. PRECIPITATION CHANCES WILL SLIDE SOUTH
AND EAST THROUGH THE EVENING...AND SHOULD GENERALLY BE DONE BY 06Z.
THE RAP AND THE NAM DO INDICATE AN INCREASE IN DEEP LAYER SHEAR AS A
SHORTWAVE TROUGH OVER THE DAKOTAS SLIDES SOUTHEAST THIS EVENING. IS
NOT OUT OF THE QUESTION TO GET AN ISOLATED STORM THAT IS ABLE TO GET
ORGANIZED AND PRODUCE HAIL OR STRONG WINDS...BUT FEEL IT WILL BE
SHORT LIVED AND NO REAL THREAT FOR SEVERE STORMS IS CURRENTLY A
CONCERN.
AS THE SHORTWAVE OVER SOUTH DAKOTA MOVES SOUTHEAST INTO NORTHERN
NEBRASKA LATER THIS EVENING AND OVERNIGHT THERE ARE INDICATIONS OF
WARM AIR ADVECTION AND STRONGER LIFT AHEAD OF IT...ALONG WITH
MOISTURE TRANSPORT IN THE 850MB TO 700MB LAYER. ALTHOUGH NONE OF
THIS IS REAL STRONG COULD GET MORE CONVECTION TONIGHT. IF IT DOES
DEVELOP...ONE QUESTION WILL BE HOW FAR WEST IT WILL BE. CURRENT
SUITE OF MODELS SHOW MOST OF THIS ACTIVITY WILL JUST SKIRT THE LOCAL
FORECAST AREA...MAINLY KEEPS IT OVER NORTHEAST NEBRASKA.
THEN FOR SUNDAY...NOT MUCH CHANGE IN THE GENERAL WEATHER PATTERN.
TEMPERATURES ALOFT WARM SLIGHTLY BUT NOT MUCH SO STILL LOOKING FOR
HIGHS NEAR 90 OR IN THE LOW 90S MOST LOCATIONS. WITH THE EXCEPTION
OF THE GFS...MODELS ARE ALL DEVELOPING CONVECTION IN THE AFTERNOON
ALONG A WEAK SURFACE FRONT FROM NORTHWEST TO SOUTH CENTRAL NEBRASKA.
STRONG DAYTIME HEATING WILL AGAIN DESTABILIZE THE LOW LEVELS OF THE
TROPOSPHERE AND WILL CREATE STEEP LAPSE RATES WITH MIXING TO NEAR
650MB. ALSO...THERE IS A WEAK SHORTWAVE PROJECTED TO MOVE INTO
NORTHWEST NEBRASKA NEAR MID AFTERNOON TO ENHANCE THE LIFT IN THE
AREA. AS SIMILAR CONDITIONS OVER THE PAST SEVERAL DAYS HAVE CAUSED
DEVELOPMENT OF ISOLATED TO SCATTERED SHOWER AND THUNDERSTORM
ACTIVITY SEE NO REASON WHY IT WON/T OCCUR AGAIN SUNDAY AFTERNOON AND
HAVE ADDED CHANCES FOR PRECIPITATION INTO THE FORECAST.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 320 PM CDT SAT AUG 2 2014
SUNDAY NIGHT...WRN STATES UPPER RIDGE AXIS BUILDS EWD AS UPPER LOW
OVER SERN CANADA ALSO SHIFTS EWD. SURFACE HIGH PRESSURE BEGINS TO
SLIDE SWD INTO THE GREAT LAKES AND UPPER MISSISSIPPI VALLEY WHICH
ALLOWS A WEAK BOUNDARY TO BACK WWD INTO THE NERN PORTION OF THE FCST
AREA SUNDAY NIGHT INTO MONDAY. AS THIS HAPPENS...LEE SIDE LOW
PRESSURE REDEVLOPS ACROSS THE NRN HIGH PLAINS SETTING UP A
BAROCLINIC ZONE ALONG THE PERIPHERY OF THE ERN SIDE OF THE UPPER
RIDGE AXIS...ACROSS THE DAKOTAS AND NRN NEBRASKA. THE ULITMATE
PLACEMENT OF THIS FRONTAL BOUNDARY WILL BE KEY TO THE PRECIPITATION
FCST THROUGH THE WEEK AND IS DISCUSSED FURTHER BELOW. MODELS ARE
SIMILAR WITH THIS PLACEMENT BY MONDAY THOUGH DIFFER BEYOND. THE NRN
PORTION OF THIS BOUNDARY BECOMES CO-LOCATED WITH AN AREA OF MID
LEVEL FRONTOGENESIS SUNDAY EVE WHICH WILL HELP TO GENERATE DEEP
LAYER LIFT AND A BETTER CHC OF THUNDERSTORMS NORTH OF NEB SUNDAY
EVE. HOWEVER...UPPER NW FLOW HAS GENERATED ISOLATED THUNDERSTORMS IN
THE CURRENT PATTERN DUE TO WEAK BOUNDARY INTERACTIONS AND STEEP
LAPSE RATES ALOFT...AND WOULD EXPECT A SIMILAR SCENARIO FOR SUNDAY
EVE FURTHER SOUTH INTO WESTERN AND NORTH CENTRAL NEB...AND THEREFORE
SLIGHT CHANCES FOR THUNDERSTORMS WILL BE IN THE FCST BEFORE MIDNIGHT
SUNDAY. MIN TEMPS SUNDAY NIGHT NEAR TO SLIGHTLY ABOVE AVERAGE FOR THIS
TIME OF YEAR.
MONDAY INTO TUESDAY THE SHIFT IN THE RIDGE AXIS ALONG THE FRONT
RANGE ALLOWS SUBSIDENCE AND DRYING TO OCCUR OVER THE HIGHER TERRAIN
FURTHER WEST. THIS IN TURN WILL ALLOW FOR A RETURN OF THE NOCTURNAL HIGH
PLAINS LLJ WHICH DEVELOPS IN RESPONSE TO THE MORE RAPID COOLING OF
THE HIGHER TERRAIN IN THE EVENING COMPARED TO A MORE MOIST
ATMOSPHERE FURTHER EAST. THIS LLJ ALSO STRENGTHENS IN RESPONSE TO
UPPER PV ANOMALIES ROUNDING THE NOW FLATTENED RIDGE WITH ASSOCIATED
SFC CYCLOGENESIS FAVORING THE WY/CO FRONT RANGE AND WRN HIGH PLAINS
BY MID WEEK. THIS ALL SETS THE STAGE FOR INCREASED THUNDERSTORM
DEVELOPMENT...ESPECIALLY DURING THE LATE EVENING AND OVERNIGHT
HOURS...MONDAY AND TUESDAY AND ON INTO THE REST OF THE WEEK. THE
PREVIOUSLY MENTIONED FRONTAL BOUNDARY CONTINUES TO SAG FURTHER SWD
AND EVENTUALLY ACROSS THE WESTERN AND NORTH CENTRAL PORTION OF
NEBRASKA DURING MID WEEK. THE LLJ WILL BE EFFICIENT AT SUPPLYING LOW
LEVEL MOISTURE TO THE ATMOSPHERE WHICH WILL BE FURTHER ENHANCED BY
TROPICAL MOISTURE MOVING NWD THROUGH THE GREAT BASIN AREA AROUND THE
AFOREMENTIONED UPPER HIGH. THE RESULT IS PW VALUES APPROACHING +2
STANDARD DEVIATIONS ABOVE THE MEAN FOR THIS TIME OF YEAR...NEARING
1.75 INCHES BY THU. IN ADDITION...MODEST INSTABILITY DEVELOPS E OF
THE STATIONARY/WARM FRONTAL BOUNDARY IN ERN NEB EARLY IN THE WEEK
BUT SHIFTS SWWD BY WED/THU TIME FRAME AS DOES THE BOUNDARY. THE
SPECIFIC DETAILS OF BOUNDARY LOCATION FROM DAY TO DAY WILL BE
DETERMINED LARGELY BY EACH ITERATION OF CONVECTIVE DEVELOPMENT AS
MESOSCALE COLD POOL AUGMENTATION OF THE BOUNDARY TAKES
PLACE...MAKING SPECIFIC DETAILS OF THUNDERSTORM DEVELOPMENT
DIFFICULT. IN GENERAL...THE DEVELOPING LARGE SCALE PATTERN BY MID
WEEK SUPPORTS AN INCREASED CONFIDENCE IN INCREASING THUNDERSTORM
CHANCES THROUGH THE WEEK. DAYTIME MAX TEMPERATURES WILL BE AVERAGE
TO SLIGHTLY ABOVE TO START THE WEEK...BUT WILL LOWER TO BELOW
AVERAGE BY THE END OF THE WEEK. THE DIURNAL RANGE OF TEMPS AS THE
WEEK PROGRESSES HOWEVER LESSENS WITH LOWS REMAINING NEAR OR ABOVE
AVERAGE THROUGH THE WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 658 PM CDT SAT AUG 2 2014
THUNDERSTORMS IN WESTERN NEBRASKA ARE EXPECTED TO WEAKEN AS THEY
LOSE THE ENERGY FROM DAYTIME HEATING. THERE IS STILL A POSSIBILITY
OF ANOTHER THUNDERSTORM AT KLBF...BUT THE PROBABILITY IS TOO LOW
FOR INCLUSION IN THE TERMINAL FORECAST. ELSEWHERE...STORMS COULD
AFFECT OGA AND BBW BEFORE 02Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SPRINGER
SYNOPSIS...BROOKS
SHORT TERM...BROOKS
LONG TERM...JWS
AVIATION...SPRINGER
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
659 PM CDT SAT AUG 2 2014
.SYNOPSIS...
ISSUED AT 320 PM CDT SAT AUG 2 2014
THE WESTERN CONUS RIDGE/EASTERN CONUS TROUGH PATTERN CONTINUES IN
THE UPPER LEVELS WITH THE CENTRAL PLAINS UNDER THE INFLUENCE OF
NORTHWEST FLOW WITH WEAK SHORTWAVES PERIODICALLY MOVING OVER THE
RIDGE AND ACROSS THE AREA AS THEY DIVE INTO THE TROUGH. AT
19Z...NOTING A SHORTWAVE TROUGH MOVING INTO NORTHERN SOUTH
DAKOTA...WITH ANOTHER OVER SOUTHERN WYOMING. 02.12Z SOUNDINGS SHOWED
700MB TEMPERATURES OF 9C AND 8C AT KUNR AND KLBF RESPECTIVELY...WITH
5C AND 6C AT KABR AND KOAX. THIS WOULD INDICATE THAT ALTHOUGH THE
AREA IS UNDER NORTHWEST FLOW...THE WARM AIR ALOFT UNDER THE RIDGE
CONTINUES TO STAY IN PLACE ACROSS THE WESTERN PLAINS. HOWEVER...THIS
AIR IS NOT WARM ENOUGH TO CAP THE BOUNDARY LAYER. AT THE
SURFACE...LOW PRESSURE WAS SITUATED OVER SOUTH CENTRAL SOUTH
DAKOTA...JUST NORTH AND EAST OF KVTN WITH A WEAK TROUGH OF LOW
PRESSURE EXTENDING SOUTH THEN WEST /TO AROUND KBBW THROUGH KLBF AND
KOGA. STRONG HEATING AT THE SURFACE WITH HIGHS IN THE UPPER 80S AND
LOW 90S HAS CREATED DEEP MIXING UP TO 600MB AND WITH STEEP LAPSE
RATES CONVECTION HAS BEGUN TO DEVELOP ACROSS THE AREA WHERE
CONVERGENT BOUNDARIES EXIST. MU CAPES ARE 1500 TO 2000 J/KG BUT
THERE IS VERY LITTLE SHEAR OVER ONGOING CONVECTION SO ACTIVITY HAS
BEEN VERY UNORGANIZED THUS FAR THIS AFTERNOON.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 320 PM CDT SAT AUG 2 2014
SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH THE AFTERNOON AND
INTO THIS EVENING UNTIL LOSS OF DAYTIME HEATING STABILIZES THE
BOUNDARY LAYER AND CUTS OFF THE ENERGY INTO THE STORMS. THE SURFACE
LOW OVER SOUTH DAKOTA WILL SLOWLY MOVE SOUTHEAST THROUGH THE EVENING
WITH THE PRECIPITATION GENERALLY STAYING ALONG AND SOUTH OF AN ARC
FROM THE LOW TO KTIF TO KAIA. PRECIPITATION CHANCES WILL SLIDE SOUTH
AND EAST THROUGH THE EVENING...AND SHOULD GENERALLY BE DONE BY 06Z.
THE RAP AND THE NAM DO INDICATE AN INCREASE IN DEEP LAYER SHEAR AS A
SHORTWAVE TROUGH OVER THE DAKOTAS SLIDES SOUTHEAST THIS EVENING. IS
NOT OUT OF THE QUESTION TO GET AN ISOLATED STORM THAT IS ABLE TO GET
ORGANIZED AND PRODUCE HAIL OR STRONG WINDS...BUT FEEL IT WILL BE
SHORT LIVED AND NO REAL THREAT FOR SEVERE STORMS IS CURRENTLY A
CONCERN.
AS THE SHORTWAVE OVER SOUTH DAKOTA MOVES SOUTHEAST INTO NORTHERN
NEBRASKA LATER THIS EVENING AND OVERNIGHT THERE ARE INDICATIONS OF
WARM AIR ADVECTION AND STRONGER LIFT AHEAD OF IT...ALONG WITH
MOISTURE TRANSPORT IN THE 850MB TO 700MB LAYER. ALTHOUGH NONE OF
THIS IS REAL STRONG COULD GET MORE CONVECTION TONIGHT. IF IT DOES
DEVELOP...ONE QUESTION WILL BE HOW FAR WEST IT WILL BE. CURRENT
SUITE OF MODELS SHOW MOST OF THIS ACTIVITY WILL JUST SKIRT THE LOCAL
FORECAST AREA...MAINLY KEEPS IT OVER NORTHEAST NEBRASKA.
THEN FOR SUNDAY...NOT MUCH CHANGE IN THE GENERAL WEATHER PATTERN.
TEMPERATURES ALOFT WARM SLIGHTLY BUT NOT MUCH SO STILL LOOKING FOR
HIGHS NEAR 90 OR IN THE LOW 90S MOST LOCATIONS. WITH THE EXCEPTION
OF THE GFS...MODELS ARE ALL DEVELOPING CONVECTION IN THE AFTERNOON
ALONG A WEAK SURFACE FRONT FROM NORTHWEST TO SOUTH CENTRAL NEBRASKA.
STRONG DAYTIME HEATING WILL AGAIN DESTABILIZE THE LOW LEVELS OF THE
TROPOSPHERE AND WILL CREATE STEEP LAPSE RATES WITH MIXING TO NEAR
650MB. ALSO...THERE IS A WEAK SHORTWAVE PROJECTED TO MOVE INTO
NORTHWEST NEBRASKA NEAR MID AFTERNOON TO ENHANCE THE LIFT IN THE
AREA. AS SIMILAR CONDITIONS OVER THE PAST SEVERAL DAYS HAVE CAUSED
DEVELOPMENT OF ISOLATED TO SCATTERED SHOWER AND THUNDERSTORM
ACTIVITY SEE NO REASON WHY IT WON/T OCCUR AGAIN SUNDAY AFTERNOON AND
HAVE ADDED CHANCES FOR PRECIPITATION INTO THE FORECAST.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 320 PM CDT SAT AUG 2 2014
SUNDAY NIGHT...WRN STATES UPPER RIDGE AXIS BUILDS EWD AS UPPER LOW
OVER SERN CANADA ALSO SHIFTS EWD. SURFACE HIGH PRESSURE BEGINS TO
SLIDE SWD INTO THE GREAT LAKES AND UPPER MISSISSIPPI VALLEY WHICH
ALLOWS A WEAK BOUNDARY TO BACK WWD INTO THE NERN PORTION OF THE FCST
AREA SUNDAY NIGHT INTO MONDAY. AS THIS HAPPENS...LEE SIDE LOW
PRESSURE REDEVLOPS ACROSS THE NRN HIGH PLAINS SETTING UP A
BAROCLINIC ZONE ALONG THE PERIPHERY OF THE ERN SIDE OF THE UPPER
RIDGE AXIS...ACROSS THE DAKOTAS AND NRN NEBRASKA. THE ULITMATE
PLACEMENT OF THIS FRONTAL BOUNDARY WILL BE KEY TO THE PRECIPITATION
FCST THROUGH THE WEEK AND IS DISCUSSED FURTHER BELOW. MODELS ARE
SIMILAR WITH THIS PLACEMENT BY MONDAY THOUGH DIFFER BEYOND. THE NRN
PORTION OF THIS BOUNDARY BECOMES CO-LOCATED WITH AN AREA OF MID
LEVEL FRONTOGENESIS SUNDAY EVE WHICH WILL HELP TO GENERATE DEEP
LAYER LIFT AND A BETTER CHC OF THUNDERSTORMS NORTH OF NEB SUNDAY
EVE. HOWEVER...UPPER NW FLOW HAS GENERATED ISOLATED THUNDERSTORMS IN
THE CURRENT PATTERN DUE TO WEAK BOUNDARY INTERACTIONS AND STEEP
LAPSE RATES ALOFT...AND WOULD EXPECT A SIMILAR SCENARIO FOR SUNDAY
EVE FURTHER SOUTH INTO WESTERN AND NORTH CENTRAL NEB...AND THEREFORE
SLIGHT CHANCES FOR THUNDERSTORMS WILL BE IN THE FCST BEFORE MIDNIGHT
SUNDAY. MIN TEMPS SUNDAY NIGHT NEAR TO SLIGHTLY ABOVE AVERAGE FOR THIS
TIME OF YEAR.
MONDAY INTO TUESDAY THE SHIFT IN THE RIDGE AXIS ALONG THE FRONT
RANGE ALLOWS SUBSIDENCE AND DRYING TO OCCUR OVER THE HIGHER TERRAIN
FURTHER WEST. THIS IN TURN WILL ALLOW FOR A RETURN OF THE NOCTURNAL HIGH
PLAINS LLJ WHICH DEVELOPS IN RESPONSE TO THE MORE RAPID COOLING OF
THE HIGHER TERRAIN IN THE EVENING COMPARED TO A MORE MOIST
ATMOSPHERE FURTHER EAST. THIS LLJ ALSO STRENGTHENS IN RESPONSE TO
UPPER PV ANOMALIES ROUNDING THE NOW FLATTENED RIDGE WITH ASSOCIATED
SFC CYCLOGENESIS FAVORING THE WY/CO FRONT RANGE AND WRN HIGH PLAINS
BY MID WEEK. THIS ALL SETS THE STAGE FOR INCREASED THUNDERSTORM
DEVELOPMENT...ESPECIALLY DURING THE LATE EVENING AND OVERNIGHT
HOURS...MONDAY AND TUESDAY AND ON INTO THE REST OF THE WEEK. THE
PREVIOUSLY MENTIONED FRONTAL BOUNDARY CONTINUES TO SAG FURTHER SWD
AND EVENTUALLY ACROSS THE WESTERN AND NORTH CENTRAL PORTION OF
NEBRASKA DURING MID WEEK. THE LLJ WILL BE EFFICIENT AT SUPPLYING LOW
LEVEL MOISTURE TO THE ATMOSPHERE WHICH WILL BE FURTHER ENHANCED BY
TROPICAL MOISTURE MOVING NWD THROUGH THE GREAT BASIN AREA AROUND THE
AFOREMENTIONED UPPER HIGH. THE RESULT IS PW VALUES APPROACHING +2
STANDARD DEVIATIONS ABOVE THE MEAN FOR THIS TIME OF YEAR...NEARING
1.75 INCHES BY THU. IN ADDITION...MODEST INSTABILITY DEVELOPS E OF
THE STATIONARY/WARM FRONTAL BOUNDARY IN ERN NEB EARLY IN THE WEEK
BUT SHIFTS SWWD BY WED/THU TIME FRAME AS DOES THE BOUNDARY. THE
SPECIFIC DETAILS OF BOUNDARY LOCATION FROM DAY TO DAY WILL BE
DETERMINED LARGELY BY EACH ITERATION OF CONVECTIVE DEVELOPMENT AS
MESOSCALE COLD POOL AUGMENTATION OF THE BOUNDARY TAKES
PLACE...MAKING SPECIFIC DETAILS OF THUNDERSTORM DEVELOPMENT
DIFFICULT. IN GENERAL...THE DEVELOPING LARGE SCALE PATTERN BY MID
WEEK SUPPORTS AN INCREASED CONFIDENCE IN INCREASING THUNDERSTORM
CHANCES THROUGH THE WEEK. DAYTIME MAX TEMPERATURES WILL BE AVERAGE
TO SLIGHTLY ABOVE TO START THE WEEK...BUT WILL LOWER TO BELOW
AVERAGE BY THE END OF THE WEEK. THE DIURNAL RANGE OF TEMPS AS THE
WEEK PROGRESSES HOWEVER LESSENS WITH LOWS REMAINING NEAR OR ABOVE
AVERAGE THROUGH THE WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 658 PM CDT SAT AUG 2 2014
THUNDERSTORMS IN WESTERN NEBRASKA ARE EXPECTED TO WEAKEN AS THEY
LOSE THE ENERGY FROM DAYTIME HEATING. THERE IS STILL A POSSIBILITY
OF ANOTHER THUNDERSTORM AT KLBF...BUT THE PROBABILITY IS TOO LOW
FOR INCLUSION IN THE TERMINAL FORECAST. ELSEWHERE...STORMS COULD
AFFECT OGA AND BBW BEFORE 02Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BROOKS
SHORT TERM...BROOKS
LONG TERM...JWS
AVIATION...SPRINGER
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1248 PM CDT FRI AUG 1 2014
.UPDATE...
ISSUED AT 1206 PM CDT FRI AUG 1 2014
INHERITED FORECAST FROM EARLY THIS MORNING REMAINS LARGELY ON
TRACK THROUGH THE AFTERNOON HOURS...AS CONFIDENCE REMAINS HIGH IN
DRY CONDITIONS CWA-WIDE UNDER PLENTY OF SUNSHINE. OTHER THAN THE
USUAL MINOR TWEAKS TO MATCH THE LATEST OBSERVED DATA...DID NUDGE
DOWN HIGH TEMPS GENERALLY 1-3 DEGREES...LEANING THE MAJORITY OF
THE CWA MORE INTO THE MID-UPPER 80S RANGE VERSUS UPPER 80S-LOW
90S...ALTHOUGH STILL ANTICIPATE SOME SOUTHERN ZONES MAINLY IN KS
TO TOUCH 90. OVERALL THOUGH...TODAY IS TRENDING A FEW DEGREES
COOLER THAN YESTERDAY WAS. THE LATEST FORECAST REFLECTS NO
UPDATES/CHANGES YET FOR TONIGHT AND BEYOND.
UPDATE ISSUED AT 621 AM CDT FRI AUG 1 2014
JUST SOME MINOR BRUSH-UPS ON TEMPS/DWPTS FOR THIS ENHANCED SHORT-
TERM FCST /ESTF/ UPDATE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 341 AM CDT FRI AUG 1 2014
...SEASONABLE TEMPS AND DRY TODAY FOLLOWED BY ANOTHER MINOR THREAT
OF A STORM OR TWO TONIGHT...
ALOFT: STAGNANT NW FLOW REMAINS THRU TONIGHT. THERE IS A MINOR
UNDULATION /SHORTWAVE TROF/ ON THE TROPOPAUSE ALONG THE MT-ALBERTA
BORDER EARLY THIS MORNING...AND IT IS SUSTAINING OVERNIGHT TSTMS.
THIS WAVE WILL ROUND THE RIDGE AND DROP SE INTO THE DAKOTAS THIS
AFTERNOON AND INTO NEB TONIGHT.
SURFACE: JUST AS YESTERDAY EXPANSIVE W ATLANTIC HIGH PRES
ENCOMPASSES THE ENTIRE CNTRL/ERN USA WITH A LARGELY BAROTROPIC
REGIME IN PLACE. AS YESTERDAYS WEAK SFC LOW FILLS AND DISAPPEARS
TODAY...THE NEXT WEAK LOW OVER MT WILL SLOWLY SLIP DOWN THE SD/WY
BORDER THRU TONIGHT.
EARLY THIS MORNING: MOSTLY CLEAR AND QUIET. LOW TEMPS OF 55-62F
WILL OCCUR RIGHT AROUND SUNRISE.
WE HAVE NOTED A COUPLE SHWRS AND EVEN A TSTM HAVE DEVELOPED OVER
CNTRL SD BETWEEN 2-3 AM. THIS IS A BIT BOTHERSOME AS I HAVE THE
FCST DRY DURING THE TODAY. THE 04Z HRRR ENSEMBLE DOES HAVE TWO
RUNS THAT BRING A FADING SHWR OR TWO DOWN TO THE SANDHILLS. THIS
WILL NEED TO BE WATCHED BY THE DAY SHIFT TO ENSURE THEY ACTUALLY
DISSIPATE.
TODAY: SUNNY WITH SOME STRAY PATCHES OF CIRRUS OF ALTOCU
OCCASIONALLY FLOATING THRU. SUBSIDENCE BEHIND YESTERDAYS
DEPARTING TROF SHOULD PRODUCE ENOUGH OF A CAP TO SUPPORT A DRY
FCST.
AS FOR HIGH TEMPS...WAS NOT PLEASED WITH ANY OF WHAT THE GUIDANCE
OFFERED. YESTERDAYS HIGHS /85-92F/ WERE 3-5F HIGHER THAN THIS FCSTR
ANTICIPATED AND YET NEARLY ALL OF THE 00Z GUIDANCE OFFERS NOTHING
NEAR THAT...DESPITE 850 MB TEMPS BEING ABOUT THE SAME. THE 06Z
RAP WAS THE WARMEST AVAILABLE GUIDANCE AND I BLENDED IT WITH THE
OBSERVED TEMPS FROM YESTERDAY. THIS SHOULD DO WELL WITH NEARLY
FULL SUN.
USED STRAIGHT MAV DEWPOINTS AT 21Z TO BETTER CAPTURE THE LOWEST
RH VS THE CONSENSUS GUIDANCE.
ISOLATED HIGH-BASED TSTMS WILL DEVELOP OVER WRN SD DOWN INTO THE
SANDHILLS THIS AFTERNOON IN THE CONVERGENCE ASSOCIATED WITH THE SFC
LOW.
TONIGHT: TURNING P/CLOUDY AS CLOUD DEBRIS FROM UPSTREAM TSTMS DRIFTS
INTO THE FCST AREA. CANT RULE OUT A COUPLE ISOLATED SHWRS/TSTMS
ROAMING INTO AREAS N OF I-80. INSTABILITY LOOKS WEAK WITH MLCAPE NO
MORE THAN 500 J/KG WITH A SKINNY CAPE PROFILE. CINH REMAINS IN THE
FCST SOUNDINGS. SO IT MAY TAKE AN OUTFLOW BOUNDARY TO MAINTAIN
ANY STORMS THAT THREATEN FROM THE NW.
THE HIGHEST PROBABILITIES FOR MEASURABLE RAIN VIA THE 03Z/SREF WILL
REMAIN NW OF THE FCST AREA...BUT THAT DOES NOT MEAN A STRAY SHWR OR
TSTM WONT MAKE IT HERE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 341 AM CDT FRI AUG 1 2014
GUIDANCE SUGGESTS NORTHWESTERLY UPPER TROPOSPHERIC FLOW WILL BE
NOTED ACROSS THE CENTRAL PLAINS TO THE START THE LONG TERM
FORECAST PERIOD...ALTHOUGH THIS FLOW IS EXPECTED TO WEAKEN DURING
THE WEEKEND AS UPPER TROPOSPHERIC RIDGING BUILDS INTO THE REGION
FROM THE SOUTHWEST. THE UPPER TROPOSPHERIC FLOW IS THEN EXPECTED
TO BECOME MORE ZONAL BY TUESDAY OR WEDNESDAY AS AN UPPER
TROPOSPHERIC SHORT WAVE MOVES INTO THE CENTRAL CONUS FROM THE
NORTH/NORTHWEST. CLOSER TO THE SURFACE...LOWER TROPOSPHERIC FLOW
IS EXPECTED TO REMAIN FROM THE SOUTH FOR THE MOST PART SATURDAY
THROUGH TUESDAY. BY WEDNESDAY HOWEVER...THE AFOREMENTIONED UPPER
TROPOSPHERIC SHORT WAVE IS EXPECTED TO PROMOTE AN AREA OF LOW
BAROMETRIC PRESSURE AT THE SURFACE OVER EASTERN NEBRASKA...WITH
THIS LOW EXPECTED TO MOVE EAST THUS ALLOWING A LOWER TROPOSPHERIC
BAROCLINIC ZONE TO CLEAR OUR AREA AND ALLOW FOR MORE OF A
NORTHERLY LOWER TROPOSPHERIC WIND FIELD WEDNESDAY AND THURSDAY.
VARIOUS SETS OF GUIDANCE SUGGEST SUBTLE UPPER TROPOSPHERIC
PERTURBATIONS MOVING WITHIN THE MEAN NORTHWESTERLY FLOW COULD
PROMOTE PRECIPITATION PRODUCTION ACROSS PORTIONS OF OUR AREA AT
TIMES SATURDAY THROUGH MONDAY. UNFORTUNATELY...QPF FIELDS FROM
VARIOUS SETS OF MODEL GUIDANCE ARE ALL OVER THE PLACE...WITH NO
TWO SETS OF GUIDANCE IN AGREEMENT AS TO WHEN AND/OR WHERE
PRECIPITATION WILL ACTUALLY BE REALIZED. GIVEN THE DISAGREEMENT
BETWEEN VARIOUS MODELS...OPTED TO GO AHEAD AND MAINTAIN THE DRY
FORECAST WHICH WAS INHERITED...WITH THE HOPES THAT FUTURE MODEL
RUNS WILL PRESENT A MORE CONCRETE SOLUTION WITH RESPECT TO
PRECIPITATION CHANCES AT SOME POINT BETWEEN SATURDAY AND MONDAY.
STARTING TUESDAY...OMEGA IS EXPECTED TO INCREASE ACROSS THE
REGION AS THE AFOREMENTIONED UPPER TROPOSPHERIC SHORT WAVE
APPROACHES FROM THE NORTH/NORTHWEST. ALLBLEND RESPONDED BY
PRESENTING 20-40% POPS TO MUCH OF THE AREA TUESDAY THROUGH
WEDNESDAY NIGHT...WITH SOMEWHAT LOWER POPS HEADING INTO THE DAY
THURSDAY. THESE POPS WERE LEFT UNCHANGED FOR THE MOST PART.
LITTLE CHANGE IN THE LOWER TROPOSPHERIC AIR MASS IS EXPECTED TO
PROMOTE SIMILAR TEMPERATURE READINGS FROM DAY TO DAY ACROSS OUR
AREA SATURDAY THROUGH TUESDAY...WITH AFTERNOON HIGHS IN THE UPPER
80S TO LOWER 90S AND OVERNIGHT LOWS IN THE 60S TO NEAR 70
CURRENTLY FORECAST. THE PASSAGE OF THE AFOREMENTIONED LOWER
TROPOSPHERIC BAROCLINIC ZONE SHOULD THEN ALLOW FOR A COOLING TREND
STARTING WEDNESDAY...WITH AFTERNOON HIGHS IN THE LOWER TO MID 80S
AND OVERNIGHT LOWS IN THE LOWER TO MID 60S EXPECTED TO FINISH THE
FORECAST PERIOD.
&&
.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z SATURDAY)
ISSUED AT 1248 PM CDT FRI AUG 1 2014
CONFIDENCE IS RATHER HIGH IN VFR CEILING/VISIBILITY THROUGH THE
PERIOD...WITH ONLY SOME INCREASING POTENTIAL FOR A POSSIBLE MID
LEVEL CEILING MAINLY DURING THE FINAL 6 HOURS OF THE PERIOD. SOME
MODELS ALSO SUGGEST SOME LIMITED POTENTIAL FOR A PASSING
SHOWER/WEAK THUNDERSTORM LATE IN THE PERIOD AS WELL...BUT
CONFIDENCE IN DEVELOPMENT/COVERAGE REMAINS TOO LOW TO EVEN JUSTIFY
A VICINITY SHOWER (VCSH) MENTION AT THIS JUNCTURE.
OTHERWISE...SURFACE WINDS SHOULD NOT BE A MAJOR ISSUE AS
SUSTAINED NORTHEASTERLY SPEEDS OF GENERALLY 10-12KT THIS
AFTERNOON WITH SLIGHTLY HIGHER GUSTS TRANSITION TO LIGHT/VARIABLE
OVERNIGHT BEFORE BECOMING SOMEWHAT MORE ESTABLISHED FROM THE
SOUTH-SOUTHEAST ON SATURDAY MORNING.
&&
.CLIMATE...
ISSUED AT 412 AM CDT FRI AUG 1 2014
THE PRELIMINARY FINAL NUMBERS ARE IN FOR JULY:
HASTINGS
TEMP 73.6 3.5F BELOW NORMAL
PRECIP 1.48 2.26 BELOW NORMAL
GRAND ISLAND
TEMP 73.4 2.8F BELOW NORMAL
PRECIP 2.19 1.21 BELOW NORMAL
ORD
TEMP 70.1 4.3F BELOW NORMAL
PRECIP 2.07 0.90 BELOW NORMAL
KEARNEY
TEMP 73.0 1.7F BELOW NORMAL
PRECIP 0.13 3.15 BELOW NORMAL
THE MONTHLY SUMMARIES WILL BE OUT LATER TODAY. BOTTOM LINE IS JULY
WAS COOLER AND DRIER THAN NORMAL.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...PFANNKUCH
SHORT TERM...HALBLAUB
LONG TERM...BRYANT
AVIATION...PFANNKUCH
CLIMATE...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1208 PM CDT FRI AUG 1 2014
.UPDATE...
ISSUED AT 1206 PM CDT FRI AUG 1 2014
INHERITED FORECAST FROM EARLY THIS MORNING REMAINS LARGELY ON
TRACK THROUGH THE AFTERNOON HOURS...AS CONFIDENCE REMAINS HIGH IN
DRY CONDITIONS CWA-WIDE UNDER PLENTY OF SUNSHINE. OTHER THAN THE
USUAL MINOR TWEAKS TO MATCH THE LATEST OBSERVED DATA...DID NUDGE
DOWN HIGH TEMPS GENERALLY 1-3 DEGREES...LEANING THE MAJORITY OF
THE CWA MORE INTO THE MID-UPPER 80S RANGE VERSUS UPPER 80S-LOW
90S...ALTHOUGH STILL ANTICIPATE SOME SOUTHERN ZONES MAINLY IN KS
TO TOUCH 90. OVERALL THOUGH...TODAY IS TRENDING A FEW DEGREES
COOLER THAN YESTERDAY WAS. THE LATEST FORECAST REFLECTS NO
UPDATES/CHANGES YET FOR TONIGHT AND BEYOND.
UPDATE ISSUED AT 621 AM CDT FRI AUG 1 2014
JUST SOME MINOR BRUSH-UPS ON TEMPS/DWPTS FOR THIS ENHANCED SHORT-
TERM FCST /ESTF/ UPDATE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 341 AM CDT FRI AUG 1 2014
...SEASONABLE TEMPS AND DRY TODAY FOLLOWED BY ANOTHER MINOR THREAT
OF A STORM OR TWO TONIGHT...
ALOFT: STAGNANT NW FLOW REMAINS THRU TONIGHT. THERE IS A MINOR
UNDULATION /SHORTWAVE TROF/ ON THE TROPOPAUSE ALONG THE MT-ALBERTA
BORDER EARLY THIS MORNING...AND IT IS SUSTAINING OVERNIGHT TSTMS.
THIS WAVE WILL ROUND THE RIDGE AND DROP SE INTO THE DAKOTAS THIS
AFTERNOON AND INTO NEB TONIGHT.
SURFACE: JUST AS YESTERDAY EXPANSIVE W ATLANTIC HIGH PRES
ENCOMPASSES THE ENTIRE CNTRL/ERN USA WITH A LARGELY BAROTROPIC
REGIME IN PLACE. AS YESTERDAYS WEAK SFC LOW FILLS AND DISAPPEARS
TODAY...THE NEXT WEAK LOW OVER MT WILL SLOWLY SLIP DOWN THE SD/WY
BORDER THRU TONIGHT.
EARLY THIS MORNING: MOSTLY CLEAR AND QUIET. LOW TEMPS OF 55-62F
WILL OCCUR RIGHT AROUND SUNRISE.
WE HAVE NOTED A COUPLE SHWRS AND EVEN A TSTM HAVE DEVELOPED OVER
CNTRL SD BETWEEN 2-3 AM. THIS IS A BIT BOTHERSOME AS I HAVE THE
FCST DRY DURING THE TODAY. THE 04Z HRRR ENSEMBLE DOES HAVE TWO
RUNS THAT BRING A FADING SHWR OR TWO DOWN TO THE SANDHILLS. THIS
WILL NEED TO BE WATCHED BY THE DAY SHIFT TO ENSURE THEY ACTUALLY
DISSIPATE.
TODAY: SUNNY WITH SOME STRAY PATCHES OF CIRRUS OF ALTOCU
OCCASIONALLY FLOATING THRU. SUBSIDENCE BEHIND YESTERDAYS
DEPARTING TROF SHOULD PRODUCE ENOUGH OF A CAP TO SUPPORT A DRY
FCST.
AS FOR HIGH TEMPS...WAS NOT PLEASED WITH ANY OF WHAT THE GUIDANCE
OFFERED. YESTERDAYS HIGHS /85-92F/ WERE 3-5F HIGHER THAN THIS FCSTR
ANTICIPATED AND YET NEARLY ALL OF THE 00Z GUIDANCE OFFERS NOTHING
NEAR THAT...DESPITE 850 MB TEMPS BEING ABOUT THE SAME. THE 06Z
RAP WAS THE WARMEST AVAILABLE GUIDANCE AND I BLENDED IT WITH THE
OBSERVED TEMPS FROM YESTERDAY. THIS SHOULD DO WELL WITH NEARLY
FULL SUN.
USED STRAIGHT MAV DEWPOINTS AT 21Z TO BETTER CAPTURE THE LOWEST
RH VS THE CONSENSUS GUIDANCE.
ISOLATED HIGH-BASED TSTMS WILL DEVELOP OVER WRN SD DOWN INTO THE
SANDHILLS THIS AFTERNOON IN THE CONVERGENCE ASSOCIATED WITH THE SFC
LOW.
TONIGHT: TURNING P/CLOUDY AS CLOUD DEBRIS FROM UPSTREAM TSTMS DRIFTS
INTO THE FCST AREA. CANT RULE OUT A COUPLE ISOLATED SHWRS/TSTMS
ROAMING INTO AREAS N OF I-80. INSTABILITY LOOKS WEAK WITH MLCAPE NO
MORE THAN 500 J/KG WITH A SKINNY CAPE PROFILE. CINH REMAINS IN THE
FCST SOUNDINGS. SO IT MAY TAKE AN OUTFLOW BOUNDARY TO MAINTAIN
ANY STORMS THAT THREATEN FROM THE NW.
THE HIGHEST PROBABILITIES FOR MEASURABLE RAIN VIA THE 03Z/SREF WILL
REMAIN NW OF THE FCST AREA...BUT THAT DOES NOT MEAN A STRAY SHWR OR
TSTM WONT MAKE IT HERE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 341 AM CDT FRI AUG 1 2014
GUIDANCE SUGGESTS NORTHWESTERLY UPPER TROPOSPHERIC FLOW WILL BE
NOTED ACROSS THE CENTRAL PLAINS TO THE START THE LONG TERM
FORECAST PERIOD...ALTHOUGH THIS FLOW IS EXPECTED TO WEAKEN DURING
THE WEEKEND AS UPPER TROPOSPHERIC RIDGING BUILDS INTO THE REGION
FROM THE SOUTHWEST. THE UPPER TROPOSPHERIC FLOW IS THEN EXPECTED
TO BECOME MORE ZONAL BY TUESDAY OR WEDNESDAY AS AN UPPER
TROPOSPHERIC SHORT WAVE MOVES INTO THE CENTRAL CONUS FROM THE
NORTH/NORTHWEST. CLOSER TO THE SURFACE...LOWER TROPOSPHERIC FLOW
IS EXPECTED TO REMAIN FROM THE SOUTH FOR THE MOST PART SATURDAY
THROUGH TUESDAY. BY WEDNESDAY HOWEVER...THE AFOREMENTIONED UPPER
TROPOSPHERIC SHORT WAVE IS EXPECTED TO PROMOTE AN AREA OF LOW
BAROMETRIC PRESSURE AT THE SURFACE OVER EASTERN NEBRASKA...WITH
THIS LOW EXPECTED TO MOVE EAST THUS ALLOWING A LOWER TROPOSPHERIC
BAROCLINIC ZONE TO CLEAR OUR AREA AND ALLOW FOR MORE OF A
NORTHERLY LOWER TROPOSPHERIC WIND FIELD WEDNESDAY AND THURSDAY.
VARIOUS SETS OF GUIDANCE SUGGEST SUBTLE UPPER TROPOSPHERIC
PERTURBATIONS MOVING WITHIN THE MEAN NORTHWESTERLY FLOW COULD
PROMOTE PRECIPITATION PRODUCTION ACROSS PORTIONS OF OUR AREA AT
TIMES SATURDAY THROUGH MONDAY. UNFORTUNATELY...QPF FIELDS FROM
VARIOUS SETS OF MODEL GUIDANCE ARE ALL OVER THE PLACE...WITH NO
TWO SETS OF GUIDANCE IN AGREEMENT AS TO WHEN AND/OR WHERE
PRECIPITATION WILL ACTUALLY BE REALIZED. GIVEN THE DISAGREEMENT
BETWEEN VARIOUS MODELS...OPTED TO GO AHEAD AND MAINTAIN THE DRY
FORECAST WHICH WAS INHERITED...WITH THE HOPES THAT FUTURE MODEL
RUNS WILL PRESENT A MORE CONCRETE SOLUTION WITH RESPECT TO
PRECIPITATION CHANCES AT SOME POINT BETWEEN SATURDAY AND MONDAY.
STARTING TUESDAY...OMEGA IS EXPECTED TO INCREASE ACROSS THE
REGION AS THE AFOREMENTIONED UPPER TROPOSPHERIC SHORT WAVE
APPROACHES FROM THE NORTH/NORTHWEST. ALLBLEND RESPONDED BY
PRESENTING 20-40% POPS TO MUCH OF THE AREA TUESDAY THROUGH
WEDNESDAY NIGHT...WITH SOMEWHAT LOWER POPS HEADING INTO THE DAY
THURSDAY. THESE POPS WERE LEFT UNCHANGED FOR THE MOST PART.
LITTLE CHANGE IN THE LOWER TROPOSPHERIC AIR MASS IS EXPECTED TO
PROMOTE SIMILAR TEMPERATURE READINGS FROM DAY TO DAY ACROSS OUR
AREA SATURDAY THROUGH TUESDAY...WITH AFTERNOON HIGHS IN THE UPPER
80S TO LOWER 90S AND OVERNIGHT LOWS IN THE 60S TO NEAR 70
CURRENTLY FORECAST. THE PASSAGE OF THE AFOREMENTIONED LOWER
TROPOSPHERIC BAROCLINIC ZONE SHOULD THEN ALLOW FOR A COOLING TREND
STARTING WEDNESDAY...WITH AFTERNOON HIGHS IN THE LOWER TO MID 80S
AND OVERNIGHT LOWS IN THE LOWER TO MID 60S EXPECTED TO FINISH THE
FORECAST PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 621 AM CDT FRI AUG 1 2014
NOW THRU 13Z: GRI/EAR ARE FLIRTING WITH MVFR LIGHT FOG. HAVE A
TEMPO GROUP THRU 13Z TO ACCT FOR POSSIBLE BRIEF LOWER
VISIBILITIES. CONFIDENCE: MEDIUM
TODAY: VFR SKC. A FEW ALTOCU OR SOME THIN CIRROSTRATUS COULD
DRIFT THRU...BUT NOT OF ENOUGH CONSEQUENCE TO INCLUDE IN THE TAFS.
NNE WINDS WILL GUST UP TO 17 KTS. CONFIDENCE: HIGH
TONIGHT: VFR SKC TO START...INCREASING MID-HIGH CLOUDS AFTER
MIDNIGHT...CLOUD DEBRIS FROM UPSTREAM TSTMS. THERE IS A VERY LOW
PROBABILITY AN ISOLATED SHWR/TSTM COULD THREATEN THE TERMINALS. IT
IS TOO LOW TO INCLUDE IN THE TAFS AT THIS TIME. NNE WINDS WILL
SUBSIDE BY 01Z AND GRADUALLY SHIFT TO SE UNDER 5 KTS AND THEN
BECOME LIGHT AND VARIABLE. CONFIDENCE: MEDIUM
&&
.CLIMATE...
ISSUED AT 412 AM CDT FRI AUG 1 2014
THE PRELIMINARY FINAL NUMBERS ARE IN FOR JULY:
HASTINGS
TEMP 73.6 3.5F BELOW NORMAL
PRECIP 1.48 2.26 BELOW NORMAL
GRAND ISLAND
TEMP 73.4 2.8F BELOW NORMAL
PRECIP 2.19 1.21 BELOW NORMAL
ORD
TEMP 70.1 4.3F BELOW NORMAL
PRECIP 2.07 0.90 BELOW NORMAL
KEARNEY
TEMP 73.0 1.7F BELOW NORMAL
PRECIP 0.13 3.15 BELOW NORMAL
THE MONTHLY SUMMARIES WILL BE OUT LATER TODAY. BOTTOM LINE IS JULY
WAS COOLER AND DRIER THAN NORMAL.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...PFANNKUCH
SHORT TERM...HALBLAUB
LONG TERM...BRYANT
AVIATION...HALBLAUB
CLIMATE...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
621 AM CDT FRI AUG 1 2014
.UPDATE...
ISSUED AT 621 AM CDT FRI AUG 1 2014
JUST SOME MINOR BRUSH-UPS ON TEMPS/DWPTS FOR THIS ENHANCED SHORT-
TERM FCST /ESTF/ UPDATE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 341 AM CDT FRI AUG 1 2014
...SEASONABLE TEMPS AND DRY TODAY FOLLOWED BY ANOTHER MINOR THREAT
OF A STORM OR TWO TONIGHT...
ALOFT: STAGNANT NW FLOW REMAINS THRU TONIGHT. THERE IS A MINOR
UNDULATION /SHORTWAVE TROF/ ON THE TROPOPAUSE ALONG THE MT-ALBERTA
BORDER EARLY THIS MORNING...AND IT IS SUSTAINING OVERNIGHT TSTMS.
THIS WAVE WILL ROUND THE RIDGE AND DROP SE INTO THE DAKOTAS THIS
AFTERNOON AND INTO NEB TONIGHT.
SURFACE: JUST AS YESTERDAY EXPANSIVE W ATLANTIC HIGH PRES
ENCOMPASSES THE ENTIRE CNTRL/ERN USA WITH A LARGELY BAROTROPIC
REGIME IN PLACE. AS YESTERDAYS WEAK SFC LOW FILLS AND DISAPPEARS
TODAY...THE NEXT WEAK LOW OVER MT WILL SLOWLY SLIP DOWN THE SD/WY
BORDER THRU TONIGHT.
EARLY THIS MORNING: MOSTLY CLEAR AND QUIET. LOW TEMPS OF 55-62F
WILL OCCUR RIGHT AROUND SUNRISE.
WE HAVE NOTED A COUPLE SHWRS AND EVEN A TSTM HAVE DEVELOPED OVER
CNTRL SD BETWEEN 2-3 AM. THIS IS A BIT BOTHERSOME AS I HAVE THE
FCST DRY DURING THE TODAY. THE 04Z HRRR ENSEMBLE DOES HAVE TWO
RUNS THAT BRING A FADING SHWR OR TWO DOWN TO THE SANDHILLS. THIS
WILL NEED TO BE WATCHED BY THE DAY SHIFT TO ENSURE THEY ACTUALLY
DISSIPATE.
TODAY: SUNNY WITH SOME STRAY PATCHES OF CIRRUS OF ALTOCU
OCCASIONALLY FLOATING THRU. SUBSIDENCE BEHIND YESTERDAYS
DEPARTING TROF SHOULD PRODUCE ENOUGH OF A CAP TO SUPPORT A DRY
FCST.
AS FOR HIGH TEMPS...WAS NOT PLEASED WITH ANY OF WHAT THE GUIDANCE
OFFERED. YESTERDAYS HIGHS /85-92F/ WERE 3-5F HIGHER THAN THIS FCSTR
ANTICIPATED AND YET NEARLY ALL OF THE 00Z GUIDANCE OFFERS NOTHING
NEAR THAT...DESPITE 850 MB TEMPS BEING ABOUT THE SAME. THE 06Z
RAP WAS THE WARMEST AVAILABLE GUIDANCE AND I BLENDED IT WITH THE
OBSERVED TEMPS FROM YESTERDAY. THIS SHOULD DO WELL WITH NEARLY
FULL SUN.
USED STRAIGHT MAV DEWPOINTS AT 21Z TO BETTER CAPTURE THE LOWEST
RH VS THE CONSENSUS GUIDANCE.
ISOLATED HIGH-BASED TSTMS WILL DEVELOP OVER WRN SD DOWN INTO THE
SANDHILLS THIS AFTERNOON IN THE CONVERGENCE ASSOCIATED WITH THE SFC
LOW.
TONIGHT: TURNING P/CLOUDY AS CLOUD DEBRIS FROM UPSTREAM TSTMS DRIFTS
INTO THE FCST AREA. CANT RULE OUT A COUPLE ISOLATED SHWRS/TSTMS
ROAMING INTO AREAS N OF I-80. INSTABILITY LOOKS WEAK WITH MLCAPE NO
MORE THAN 500 J/KG WITH A SKINNY CAPE PROFILE. CINH REMAINS IN THE
FCST SOUNDINGS. SO IT MAY TAKE AN OUTFLOW BOUNDARY TO MAINTAIN
ANY STORMS THAT THREATEN FROM THE NW.
THE HIGHEST PROBABILITIES FOR MEASURABLE RAIN VIA THE 03Z/SREF WILL
REMAIN NW OF THE FCST AREA...BUT THAT DOES NOT MEAN A STRAY SHWR OR
TSTM WONT MAKE IT HERE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 341 AM CDT FRI AUG 1 2014
GUIDANCE SUGGESTS NORTHWESTERLY UPPER TROPOSPHERIC FLOW WILL BE
NOTED ACROSS THE CENTRAL PLAINS TO THE START THE LONG TERM
FORECAST PERIOD...ALTHOUGH THIS FLOW IS EXPECTED TO WEAKEN DURING
THE WEEKEND AS UPPER TROPOSPHERIC RIDGING BUILDS INTO THE REGION
FROM THE SOUTHWEST. THE UPPER TROPOSPHERIC FLOW IS THEN EXPECTED
TO BECOME MORE ZONAL BY TUESDAY OR WEDNESDAY AS AN UPPER
TROPOSPHERIC SHORT WAVE MOVES INTO THE CENTRAL CONUS FROM THE
NORTH/NORTHWEST. CLOSER TO THE SURFACE...LOWER TROPOSPHERIC FLOW
IS EXPECTED TO REMAIN FROM THE SOUTH FOR THE MOST PART SATURDAY
THROUGH TUESDAY. BY WEDNESDAY HOWEVER...THE AFOREMENTIONED UPPER
TROPOSPHERIC SHORT WAVE IS EXPECTED TO PROMOTE AN AREA OF LOW
BAROMETRIC PRESSURE AT THE SURFACE OVER EASTERN NEBRASKA...WITH
THIS LOW EXPECTED TO MOVE EAST THUS ALLOWING A LOWER TROPOSPHERIC
BAROCLINIC ZONE TO CLEAR OUR AREA AND ALLOW FOR MORE OF A
NORTHERLY LOWER TROPOSPHERIC WIND FIELD WEDNESDAY AND THURSDAY.
VARIOUS SETS OF GUIDANCE SUGGEST SUBTLE UPPER TROPOSPHERIC
PERTURBATIONS MOVING WITHIN THE MEAN NORTHWESTERLY FLOW COULD
PROMOTE PRECIPITATION PRODUCTION ACROSS PORTIONS OF OUR AREA AT
TIMES SATURDAY THROUGH MONDAY. UNFORTUNATELY...QPF FIELDS FROM
VARIOUS SETS OF MODEL GUIDANCE ARE ALL OVER THE PLACE...WITH NO
TWO SETS OF GUIDANCE IN AGREEMENT AS TO WHEN AND/OR WHERE
PRECIPITATION WILL ACTUALLY BE REALIZED. GIVEN THE DISAGREEMENT
BETWEEN VARIOUS MODELS...OPTED TO GO AHEAD AND MAINTAIN THE DRY
FORECAST WHICH WAS INHERITED...WITH THE HOPES THAT FUTURE MODEL
RUNS WILL PRESENT A MORE CONCRETE SOLUTION WITH RESPECT TO
PRECIPITATION CHANCES AT SOME POINT BETWEEN SATURDAY AND MONDAY.
STARTING TUESDAY...OMEGA IS EXPECTED TO INCREASE ACROSS THE
REGION AS THE AFOREMENTIONED UPPER TROPOSPHERIC SHORT WAVE
APPROACHES FROM THE NORTH/NORTHWEST. ALLBLEND RESPONDED BY
PRESENTING 20-40% POPS TO MUCH OF THE AREA TUESDAY THROUGH
WEDNESDAY NIGHT...WITH SOMEWHAT LOWER POPS HEADING INTO THE DAY
THURSDAY. THESE POPS WERE LEFT UNCHANGED FOR THE MOST PART.
LITTLE CHANGE IN THE LOWER TROPOSPHERIC AIR MASS IS EXPECTED TO
PROMOTE SIMILAR TEMPERATURE READINGS FROM DAY TO DAY ACROSS OUR
AREA SATURDAY THROUGH TUESDAY...WITH AFTERNOON HIGHS IN THE UPPER
80S TO LOWER 90S AND OVERNIGHT LOWS IN THE 60S TO NEAR 70
CURRENTLY FORECAST. THE PASSAGE OF THE AFOREMENTIONED LOWER
TROPOSPHERIC BAROCLINIC ZONE SHOULD THEN ALLOW FOR A COOLING TREND
STARTING WEDNESDAY...WITH AFTERNOON HIGHS IN THE LOWER TO MID 80S
AND OVERNIGHT LOWS IN THE LOWER TO MID 60S EXPECTED TO FINISH THE
FORECAST PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 621 AM CDT FRI AUG 1 2014
NOW THRU 13Z: GRI/EAR ARE FLIRTING WITH MVFR LIGHT FOG. HAVE A
TEMPO GROUP THRU 13Z TO ACCT FOR POSSIBLE BRIEF LOWER
VISIBILITIES. CONFIDENCE: MEDIUM
TODAY: VFR SKC. A FEW ALTOCU OR SOME THIN CIRROSTRATUS COULD
DRIFT THRU...BUT NOT OF ENOUGH CONSEQUENCE TO INCLUDE IN THE TAFS.
NNE WINDS WILL GUST UP TO 17 KTS. CONFIDENCE: HIGH
TONIGHT: VFR SKC TO START...INCREASING MID-HIGH CLOUDS AFTER
MIDNIGHT...CLOUD DEBRIS FROM UPSTREAM TSTMS. THERE IS A VERY LOW
PROBABILITY AN ISOLATED SHWR/TSTM COULD THREATEN THE TERMINALS. IT
IS TOO LOW TO INCLUDE IN THE TAFS AT THIS TIME. NNE WINDS WILL
SUBSIDE BY 01Z AND GRADUALLY SHIFT TO SE UNDER 5 KTS AND THEN
BECOME LIGHT AND VARIABLE. CONFIDENCE: MEDIUM
&&
.CLIMATE...
ISSUED AT 412 AM CDT FRI AUG 1 2014
THE PRELIMINARY FINAL NUMBERS ARE IN FOR JULY:
HASTINGS
TEMP 73.6 3.5F BELOW NORMAL
PRECIP 1.48 2.26 BELOW NORMAL
GRAND ISLAND
TEMP 73.4 2.8F BELOW NORMAL
PRECIP 2.19 1.21 BELOW NORMAL
ORD
TEMP 70.1 4.3F BELOW NORMAL
PRECIP 2.07 0.90 BELOW NORMAL
KEARNEY
TEMP 73.0 1.7F BELOW NORMAL
PRECIP 0.13 3.15 BELOW NORMAL
THE MONTHLY SUMMARIES WILL BE OUT LATER TODAY. BOTTOM LINE IS JULY
WAS COOLER AND DRIER THAN NORMAL.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...HALBLAUB
LONG TERM...BRYANT
AVIATION...HALBLAUB
CLIMATE...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
412 AM CDT FRI AUG 1 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 341 AM CDT FRI AUG 1 2014
...SEASONABLE TEMPS AND DRY TODAY FOLLOWED BY ANOTHER MINOR THREAT
OF A STORM OR TWO TONIGHT...
ALOFT: STAGNANT NW FLOW REMAINS THRU TONIGHT. THERE IS A MINOR
UNDULATION /SHORTWAVE TROF/ ON THE TROPOPAUSE ALONG THE MT-ALBERTA
BORDER EARLY THIS MORNING...AND IT IS SUSTAINING OVERNIGHT TSTMS.
THIS WAVE WILL ROUND THE RIDGE AND DROP SE INTO THE DAKOTAS THIS
AFTERNOON AND INTO NEB TONIGHT.
SURFACE: JUST AS YESTERDAY EXPANSIVE W ATLANTIC HIGH PRES
ENCOMPASSES THE ENTIRE CNTRL/ERN USA WITH A LARGELY BAROTROPIC
REGIME IN PLACE. AS YESTERDAYS WEAK SFC LOW FILLS AND DISAPPEARS
TODAY...THE NEXT WEAK LOW OVER MT WILL SLOWLY SLIP DOWN THE SD/WY
BORDER THRU TONIGHT.
EARLY THIS MORNING: MOSTLY CLEAR AND QUIET. LOW TEMPS OF 55-62F
WILL OCCUR RIGHT AROUND SUNRISE.
WE HAVE NOTED A COUPLE SHWRS AND EVEN A TSTM HAVE DEVELOPED OVER
CNTRL SD BETWEEN 2-3 AM. THIS IS A BIT BOTHERSOME AS I HAVE THE
FCST DRY DURING THE TODAY. THE 04Z HRRR ENSEMBLE DOES HAVE TWO
RUNS THAT BRING A FADING SHWR OR TWO DOWN TO THE SANDHILLS. THIS
WILL NEED TO BE WATCHED BY THE DAY SHIFT TO ENSURE THEY ACTUALLY
DISSIPATE.
TODAY: SUNNY WITH SOME STRAY PATCHES OF CIRRUS OF ALTOCU
OCCASIONALLY FLOATING THRU. SUBSIDENCE BEHIND YESTERDAYS
DEPARTING TROF SHOULD PRODUCE ENOUGH OF A CAP TO SUPPORT A DRY
FCST.
AS FOR HIGH TEMPS...WAS NOT PLEASED WITH ANY OF WHAT THE GUIDANCE
OFFERED. YESTERDAYS HIGHS /85-92F/ WERE 3-5F HIGHER THAN THIS FCSTR
ANTICIPATED AND YET NEARLY ALL OF THE 00Z GUIDANCE OFFERS NOTHING
NEAR THAT...DESPITE 850 MB TEMPS BEING ABOUT THE SAME. THE 06Z
RAP WAS THE WARMEST AVAILABLE GUIDANCE AND I BLENDED IT WITH THE
OBSERVED TEMPS FROM YESTERDAY. THIS SHOULD DO WELL WITH NEARLY
FULL SUN.
USED STRAIGHT MAV DEWPOINTS AT 21Z TO BETTER CAPTURE THE LOWEST
RH VS THE CONSENSUS GUIDANCE.
ISOLATED HIGH-BASED TSTMS WILL DEVELOP OVER WRN SD DOWN INTO THE
SANDHILLS THIS AFTERNOON IN THE CONVERGENCE ASSOCIATED WITH THE SFC
LOW.
TONIGHT: TURNING P/CLOUDY AS CLOUD DEBRIS FROM UPSTREAM TSTMS DRIFTS
INTO THE FCST AREA. CANT RULE OUT A COUPLE ISOLATED SHWRS/TSTMS
ROAMING INTO AREAS N OF I-80. INSTABILITY LOOKS WEAK WITH MLCAPE NO
MORE THAN 500 J/KG WITH A SKINNY CAPE PROFILE. CINH REMAINS IN THE
FCST SOUNDINGS. SO IT MAY TAKE AN OUTFLOW BOUNDARY TO MAINTAIN
ANY STORMS THAT THREATEN FROM THE NW.
THE HIGHEST PROBABILITIES FOR MEASURABLE RAIN VIA THE 03Z/SREF WILL
REMAIN NW OF THE FCST AREA...BUT THAT DOES NOT MEAN A STRAY SHWR OR
TSTM WONT MAKE IT HERE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 341 AM CDT FRI AUG 1 2014
GUIDANCE SUGGESTS NORTHWESTERLY UPPER TROPOSPHERIC FLOW WILL BE
NOTED ACROSS THE CENTRAL PLAINS TO THE START THE LONG TERM
FORECAST PERIOD...ALTHOUGH THIS FLOW IS EXPECTED TO WEAKEN DURING
THE WEEKEND AS UPPER TROPOSPHERIC RIDGING BUILDS INTO THE REGION
FROM THE SOUTHWEST. THE UPPER TROPOSPHERIC FLOW IS THEN EXPECTED
TO BECOME MORE ZONAL BY TUESDAY OR WEDNESDAY AS AN UPPER
TROPOSPHERIC SHORT WAVE MOVES INTO THE CENTRAL CONUS FROM THE
NORTH/NORTHWEST. CLOSER TO THE SURFACE...LOWER TROPOSPHERIC FLOW
IS EXPECTED TO REMAIN FROM THE SOUTH FOR THE MOST PART SATURDAY
THROUGH TUESDAY. BY WEDNESDAY HOWEVER...THE AFOREMENTIONED UPPER
TROPOSPHERIC SHORT WAVE IS EXPECTED TO PROMOTE AN AREA OF LOW
BAROMETRIC PRESSURE AT THE SURFACE OVER EASTERN NEBRASKA...WITH
THIS LOW EXPECTED TO MOVE EAST THUS ALLOWING A LOWER TROPOSPHERIC
BAROCLINIC ZONE TO CLEAR OUR AREA AND ALLOW FOR MORE OF A
NORTHERLY LOWER TROPOSPHERIC WIND FIELD WEDNESDAY AND THURSDAY.
VARIOUS SETS OF GUIDANCE SUGGEST SUBTLE UPPER TROPOSPHERIC
PERTURBATIONS MOVING WITHIN THE MEAN NORTHWESTERLY FLOW COULD
PROMOTE PRECIPITATION PRODUCTION ACROSS PORTIONS OF OUR AREA AT
TIMES SATURDAY THROUGH MONDAY. UNFORTUNATELY...QPF FIELDS FROM
VARIOUS SETS OF MODEL GUIDANCE ARE ALL OVER THE PLACE...WITH NO
TWO SETS OF GUIDANCE IN AGREEMENT AS TO WHEN AND/OR WHERE
PRECIPITATION WILL ACTUALLY BE REALIZED. GIVEN THE DISAGREEMENT
BETWEEN VARIOUS MODELS...OPTED TO GO AHEAD AND MAINTAIN THE DRY
FORECAST WHICH WAS INHERITED...WITH THE HOPES THAT FUTURE MODEL
RUNS WILL PRESENT A MORE CONCRETE SOLUTION WITH RESPECT TO
PRECIPITATION CHANCES AT SOME POINT BETWEEN SATURDAY AND MONDAY.
STARTING TUESDAY...OMEGA IS EXPECTED TO INCREASE ACROSS THE
REGION AS THE AFOREMENTIONED UPPER TROPOSPHERIC SHORT WAVE
APPROACHES FROM THE NORTH/NORTHWEST. ALLBLEND RESPONDED BY
PRESENTING 20-40% POPS TO MUCH OF THE AREA TUESDAY THROUGH
WEDNESDAY NIGHT...WITH SOMEWHAT LOWER POPS HEADING INTO THE DAY
THURSDAY. THESE POPS WERE LEFT UNCHANGED FOR THE MOST PART.
LITTLE CHANGE IN THE LOWER TROPOSPHERIC AIR MASS IS EXPECTED TO
PROMOTE SIMILAR TEMPERATURE READINGS FROM DAY TO DAY ACROSS OUR
AREA SATURDAY THROUGH TUESDAY...WITH AFTERNOON HIGHS IN THE UPPER
80S TO LOWER 90S AND OVERNIGHT LOWS IN THE 60S TO NEAR 70
CURRENTLY FORECAST. THE PASSAGE OF THE AFOREMENTIONED LOWER
TROPOSPHERIC BAROCLINIC ZONE SHOULD THEN ALLOW FOR A COOLING TREND
STARTING WEDNESDAY...WITH AFTERNOON HIGHS IN THE LOWER TO MID 80S
AND OVERNIGHT LOWS IN THE LOWER TO MID 60S EXPECTED TO FINISH THE
FORECAST PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1233 AM CDT FRI AUG 1 2014
REST OF TONIGHT: VFR SKC. N WIND 5 KTS OR LESS. CONFIDENCE: HIGH
FRI: VFR SKC. NNE WINDS WILL GUST UP TO 17 KTS. CONFIDENCE: HIGH
FRI EVE: VFR SKC...BUT SOME SCT 25K FT CIRRUS COULD INVADE TOWARD
05Z. NNE WINDS WILL SUBSIDE BY 01Z AND GRADUALLY SHIFT TO SE UNDER
5 KTS. CONFIDENCE: MEDIUM
&&
.CLIMATE...
ISSUED AT 412 AM CDT FRI AUG 1 2014
THE PRELIMINARY FINAL NUMBERS ARE IN FOR JULY:
HASTINGS
TEMP 73.6 3.5F BELOW NORMAL
PRECIP 1.48 2.26 BELOW NORMAL
GRAND ISLAND
TEMP 73.4 2.8F BELOW NORMAL
PRECIP 2.19 1.21 BELOW NORMAL
ORD
TEMP 70.1 4.3F BELOW NORMAL
PRECIP 2.07 0.90 BELOW NORMAL
KEARNEY
TEMP 73.0 1.7F BELOW NORMAL
PRECIP 0.13 3.15 BELOW NORMAL
THE MONTHLY SUMMARIES WILL BE OUT LATER TODAY. BOTTOM LINE IS JULY
WAS COOLER AND DRIER THAN NORMAL.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...HALBLAUB
LONG TERM...BRYANT
AVIATION...HALBLAUB
CLIMATE...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
341 AM CDT FRI AUG 1 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 341 AM CDT FRI AUG 1 2014
...SEASONABLE TEMPS AND DRY TODAY FOLLOWED BY ANOTHER MINOR THREAT
OF A STORM OR TWO TONIGHT...
ALOFT: STAGNANT NW FLOW REMAINS THRU TONIGHT. THERE IS A MINOR
UNDULATION /SHORTWAVE TROF/ ON THE TROPOPAUSE ALONG THE MT-ALBERTA
BORDER EARLY THIS MORNING...AND IT IS SUSTAINING OVERNIGHT TSTMS.
THIS WAVE WILL ROUND THE RIDGE AND DROP SE INTO THE DAKOTAS THIS
AFTERNOON AND INTO NEB TONIGHT.
SURFACE: JUST AS YESTERDAY EXPANSIVE W ATLANTIC HIGH PRES
ENCOMPASSES THE ENTIRE CNTRL/ERN USA WITH A LARGELY BAROTROPIC
REGIME IN PLACE. AS YESTERDAYS WEAK SFC LOW FILLS AND DISAPPEARS
TODAY...THE NEXT WEAK LOW OVER MT WILL SLOWLY SLIP DOWN THE SD/WY
BORDER THRU TONIGHT.
EARLY THIS MORNING: MOSTLY CLEAR AND QUIET. LOW TEMPS OF 55-62F
WILL OCCUR RIGHT AROUND SUNRISE.
WE HAVE NOTED A COUPLE SHWRS AND EVEN A TSTM HAVE DEVELOPED OVER
CNTRL SD BETWEEN 2-3 AM. THIS IS A BIT BOTHERSOME AS I HAVE THE
FCST DRY DURING THE TODAY. THE 04Z HRRR ENSEMBLE DOES HAVE TWO
RUNS THAT BRING A FADING SHWR OR TWO DOWN TO THE SANDHILLS. THIS
WILL NEED TO BE WATCHED BY THE DAY SHIFT TO ENSURE THEY ACTUALLY
DISSIPATE.
TODAY: SUNNY WITH SOME STRAY PATCHES OF CIRRUS OF ALTOCU
OCCASIONALLY FLOATING THRU. SUBSIDENCE BEHIND YESTERDAYS
DEPARTING TROF SHOULD PRODUCE ENOUGH OF A CAP TO SUPPORT A DRY
FCST.
AS FOR HIGH TEMPS...WAS NOT PLEASED WITH ANY OF WHAT THE GUIDANCE
OFFERED. YESTERDAYS HIGHS /85-92F/ WERE 3-5F HIGHER THAN THIS FCSTR
ANTICIPATED AND YET NEARLY ALL OF THE 00Z GUIDANCE OFFERS NOTHING
NEAR THAT...DESPITE 850 MB TEMPS BEING ABOUT THE SAME. THE 06Z
RAP WAS THE WARMEST AVAILABLE GUIDANCE AND I BLENDED IT WITH THE
OBSERVED TEMPS FROM YESTERDAY. THIS SHOULD DO WELL WITH NEARLY
FULL SUN.
USED STRAIGHT MAV DEWPOINTS AT 21Z TO BETTER CAPTURE THE LOWEST
RH VS THE CONSENSUS GUIDANCE.
ISOLATED HIGH-BASED TSTMS WILL DEVELOP OVER WRN SD DOWN INTO THE
SANDHILLS THIS AFTERNOON IN THE CONVERGENCE ASSOCIATED WITH THE SFC
LOW.
TONIGHT: TURNING P/CLOUDY AS CLOUD DEBRIS FROM UPSTREAM TSTMS DRIFTS
INTO THE FCST AREA. CANT RULE OUT A COUPLE ISOLATED SHWRS/TSTMS
ROAMING INTO AREAS N OF I-80. INSTABILITY LOOKS WEAK WITH MLCAPE NO
MORE THAN 500 J/KG WITH A SKINNY CAPE PROFILE. CINH REMAINS IN THE
FCST SOUNDINGS. SO IT MAY TAKE AN OUTFLOW BOUNDARY TO MAINTAIN
ANY STORMS THAT THREATEN FROM THE NW.
THE HIGHEST PROBABILITIES FOR MEASURABLE RAIN VIA THE 03Z/SREF WILL
REMAIN NW OF THE FCST AREA...BUT THAT DOES NOT MEAN A STRAY SHWR OR
TSTM WONT MAKE IT HERE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 341 AM CDT FRI AUG 1 2014
GUIDANCE SUGGESTS NORTHWESTERLY UPPER TROPOSPHERIC FLOW WILL BE
NOTED ACROSS THE CENTRAL PLAINS TO THE START THE LONG TERM
FORECAST PERIOD...ALTHOUGH THIS FLOW IS EXPECTED TO WEAKEN DURING
THE WEEKEND AS UPPER TROPOSPHERIC RIDGING BUILDS INTO THE REGION
FROM THE SOUTHWEST. THE UPPER TROPOSPHERIC FLOW IS THEN EXPECTED
TO BECOME MORE ZONAL BY TUESDAY OR WEDNESDAY AS AN UPPER
TROPOSPHERIC SHORT WAVE MOVES INTO THE CENTRAL CONUS FROM THE
NORTH/NORTHWEST. CLOSER TO THE SURFACE...LOWER TROPOSPHERIC FLOW
IS EXPECTED TO REMAIN FROM THE SOUTH FOR THE MOST PART SATURDAY
THROUGH TUESDAY. BY WEDNESDAY HOWEVER...THE AFOREMENTIONED UPPER
TROPOSPHERIC SHORT WAVE IS EXPECTED TO PROMOTE AN AREA OF LOW
BAROMETRIC PRESSURE AT THE SURFACE OVER EASTERN NEBRASKA...WITH
THIS LOW EXPECTED TO MOVE EAST THUS ALLOWING A LOWER TROPOSPHERIC
BAROCLINIC ZONE TO CLEAR OUR AREA AND ALLOW FOR MORE OF A
NORTHERLY LOWER TROPOSPHERIC WIND FIELD WEDNESDAY AND THURSDAY.
VARIOUS SETS OF GUIDANCE SUGGEST SUBTLE UPPER TROPOSPHERIC
PERTURBATIONS MOVING WITHIN THE MEAN NORTHWESTERLY FLOW COULD
PROMOTE PRECIPITATION PRODUCTION ACROSS PORTIONS OF OUR AREA AT
TIMES SATURDAY THROUGH MONDAY. UNFORTUNATELY...QPF FIELDS FROM
VARIOUS SETS OF MODEL GUIDANCE ARE ALL OVER THE PLACE...WITH NO
TWO SETS OF GUIDANCE IN AGREEMENT AS TO WHEN AND/OR WHERE
PRECIPITATION WILL ACTUALLY BE REALIZED. GIVEN THE DISAGREEMENT
BETWEEN VARIOUS MODELS...OPTED TO GO AHEAD AND MAINTAIN THE DRY
FORECAST WHICH WAS INHERITED...WITH THE HOPES THAT FUTURE MODEL
RUNS WILL PRESENT A MORE CONCRETE SOLUTION WITH RESPECT TO
PRECIPITATION CHANCES AT SOME POINT BETWEEN SATURDAY AND MONDAY.
STARTING TUESDAY...OMEGA IS EXPECTED TO INCREASE ACROSS THE
REGION AS THE AFOREMENTIONED UPPER TROPOSPHERIC SHORT WAVE
APPROACHES FROM THE NORTH/NORTHWEST. ALLBLEND RESPONDED BY
PRESENTING 20-40% POPS TO MUCH OF THE AREA TUESDAY THROUGH
WEDNESDAY NIGHT...WITH SOMEWHAT LOWER POPS HEADING INTO THE DAY
THURSDAY. THESE POPS WERE LEFT UNCHANGED FOR THE MOST PART.
LITTLE CHANGE IN THE LOWER TROPOSPHERIC AIR MASS IS EXPECTED TO
PROMOTE SIMILAR TEMPERATURE READINGS FROM DAY TO DAY ACROSS OUR
AREA SATURDAY THROUGH TUESDAY...WITH AFTERNOON HIGHS IN THE UPPER
80S TO LOWER 90S AND OVERNIGHT LOWS IN THE 60S TO NEAR 70
CURRENTLY FORECAST. THE PASSAGE OF THE AFOREMENTIONED LOWER
TROPOSPHERIC BAROCLINIC ZONE SHOULD THEN ALLOW FOR A COOLING TREND
STARTING WEDNESDAY...WITH AFTERNOON HIGHS IN THE LOWER TO MID 80S
AND OVERNIGHT LOWS IN THE LOWER TO MID 60S EXPECTED TO FINISH THE
FORECAST PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1233 AM CDT FRI AUG 1 2014
REST OF TONIGHT: VFR SKC. N WIND 5 KTS OR LESS. CONFIDENCE: HIGH
FRI: VFR SKC. NNE WINDS WILL GUST UP TO 17 KTS. CONFIDENCE: HIGH
FRI EVE: VFR SKC...BUT SOME SCT 25K FT CIRRUS COULD INVADE TOWARD
05Z. NNE WINDS WILL SUBSIDE BY 01Z AND GRADUALLY SHIFT TO SE UNDER
5 KTS. CONFIDENCE: MEDIUM
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...HALBLAUB
LONG TERM...BRYANT
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
558 PM MDT SAT AUG 2 2014
.AVIATION...
00Z TAF CYCLE
THUNDERSTORMS FAR FEWER IN NUMBER AND LESS INTENSE AS COMPARED TO
24 HOURS AGO. THIS IS LARGELY THE RESULT OF DRIER AND MORE STABLE
AIR SLOWLY ADVANCING WESTWARD AS THE MAIN MONSOON MOISTURE PLUME
TEMPORARILY SHIFTS FARTHER WEST INTO ARIZONA. LATEST HIGH
RESOLUTION MODELING SUGGESTS ONLY ISOLATED CONVECTION DRIFTING
WESTWARD OVER THE FOUR CORNERS REGION TO INCLUDE KFMN AS WELL AS
OVER THE WC/SW MOUNTAINS TO INCLUDE KGUP. THE LATEST NAM AND GFS
ARE MORE BULLISH ON AT LEAST SCATTERED -SHRA EXPANDING OVER WC/SW
NEW MEXICO AFTER 04Z AND SLOWLY LIFTING NWD THRU 12Z SUN.
CONFIDENCE HIGHEST FOR DIRECT IMPACTS AT KFMN AND KGUP. WILL
MAINTAIN LOW CONFIDENCE AND SHORT DURATION VCSH AT KSAF...AS WELL
AS KABQ/KAEG BUT PREDOMINATELY A VFR FORECAST EXPECTED TONIGHT.
QUIET WX EXPECTED FOR EASTERN NEW MEXICO TAF SITES. KJ
&&
.PREV DISCUSSION...300 PM MDT SAT AUG 2 2014...
.SYNOPSIS...
ABUNDANT MOISTURE WILL LINGER OVER NEW MEXICO THROUGH EARLY NEXT
WEEK...AND SLOW MOVING STORMS WILL CONTINUE TO BE CAPABLE OF
PRODUCING LOCALLY HEAVY RAIN...WHICH COULD LEAD TO FLASH FLOODING.
AREAS ALONG AND WEST OF THE CONTINENTAL DIVIDE WILL BE THE FOCUS FOR
THE HEAVIER STORMS TONIGHT AND INTO SUNDAY...WHILE THE FOCUS SLOWLY
SHIFTS TO THE NORTHWEST THIRD TO HALF SUNDAY NIGHT...AND PORTIONS OF
THE WEST AND CENTRAL MONDAY. HIGH TEMPERATURES WILL REMAIN BELOW
AVERAGE THROUGH MONDAY. A WARMING AND DRYING TREND IS EXPECTED BY
THE MIDDLE OF NEXT WEEK.
&&
.DISCUSSION...
ABUNDANT CLOUD COVER LINGERING THIS AFTERNOON...AND LAPS SHOWING THE
EAST REMAINING STABLE SO FAR. CELLS HAVE BEEN FIRING ALONG/WEST OF
THE CENTRAL MT CHAIN AND MOST NOTABLY OVER WESTERN SOCORRO COUNTY TO
THE GALLUP AREA...BUT LESS ACTIVE OVERALL COMPARED TO THIS TIME THE
LAST COUPLE OF DAYS. PWATS FROM AREA 12Z SOUNDINGS SHOWED LITTLE
CHANGE FROM FRIDAY ALTHOUGH MID LEVEL WINDS ARE TRANSITIONING AS THE
WEAK UPPER LOW PREPARES TO MOVE NORTH INTO ARIZONA. INITIAL THOUGHTS
WERE THAT THE CURRENT FLASH FLOOD WATCH MAY HAVE NEEDED TO BE
EXPANDED NORTHWARD AND SOMEWHAT EASTWARD FOR TONIGHT...BUT 12Z LOCAL
WRF...NAM AND HRRR DON/T SUPPORT THAT IDEA AND ARE RATHER SPARSE
LOOKING IN AREAL COVERAGE. THEREFORE DECIDED TO LET THE CURRENT
WATCH RIDE...WHERE MOST OF THIS AFTERNOON/S ECHOS EXIST SO FAR.
SUNDAY/SUNDAY EVENING COULD BE QUITE ACTIVE ALONG AND WEST OF THE
CONTINENTAL DIVIDE AND CAN/T RULE OUT THE POTENTIAL FOR HEAVY RAIN
OVER THAT AREA...HOWEVER STORM MOTION LOOKS TO BE GENERALLY SOUTH TO
NORTH AT 10 TO 15 MPH. MODELS SUGGEST THE EAST WILL CONTINUE TO BE
FAIRLY QUIET. AS THE UPPER LOW MOVES INTO THE GREAT BASIN
MONDAY...THE THETA-E RIDGE AXIS SHIFTS MORE SOUTHWEST TO NE OVER NEW
MEXICO...PUTTING THE FOCUS FOR STORMS MORE INTO THE NORTHWEST AND
NORTH CENTRAL AND ALLOWING THEM TO DRIFT OFF THE MTS INTO THE
NORTHEAST AND CENTRAL HIGHLANDS. THE MID TO LATE WEEK PERIOD STILL
FEATURES A SUPPRESSION OF THE RIDGE...ALLOWING THE NORTHWEST TO DRY
OUT SOME...AND A DECREASE OVERALL IN CONVECTION. HIGH TEMPERATURES
SHOULD FINALLY EXPERIENCE A REBOUND TOWARDS NORMAL FOR THE FIRST
WEEK OF AUGUST.
&&
.FIRE WEATHER...
A WET AND ACTIVE MONSOON PATTERN WILL CONTINUE OVER THE NEXT FEW
DAYS...KEEPING CRITICAL FIRE WEATHER CONDITIONS FROM DEVELOPING.
FOOTPRINTS OF WETTING RAINFALL HAVE BEEN SCATTERED EACH DAY OVER THE
PAST WEEK...BUT MOST AREAS OUTSIDE OF THE EASTERN PLAINS HAVE SEEN
PRECIPITATION ON OCCASION. WINDS WILL REMAIN LIGHT FOR THE MOST
PART...ONLY GETTING SLIGHTLY BREEZY IN THE VICINITY OF CENTRAL
GAPS/CANYONS THIS EVENING...AND OF COURSE GUSTY WITH ANY BRIEF AND
LOCALIZED THUNDERSTORM OUTFLOWS. THE FOCUS FOR STORMS WILL BE IN
SOUTHWESTERN SECTIONS OF THE FORECAST AREA TODAY AND
TONIGHT...SHIFTING TO THE WESTERN THIRD OF THE STATE SUNDAY.
THE BEST PLUME OF MOISTURE ALOFT WILL THEN BEGIN TO GRADUALLY LAY
OVER OR TOPPLE TO MORE OF A SOUTHWEST-NORTHEAST ORIENTATION MONDAY
AND TUESDAY...WITH STORMS STRETCHING FROM THE SW MOUNTAINS TO THE
NORTHERN MOUNTAINS BOTH DAYS. STORMS WILL ALSO PERIODICALLY BE
FILLING IN BETWEEN THESE AREAS. SOME LEE SIDE SURFACE TROUGHING WILL
ALLOW MODERATE BREEZES TO DEVELOP IN THE NORTHEAST MONDAY AND
TUESDAY. OVERALL HUMIDITY TRENDS WILL NOT VARY MUCH THROUGH THE NEXT
FEW DAYS WITH GOOD TO EXCELLENT RECOVERIES IN MUCH OF THE FORECAST
AREA EACH NIGHT/MORNING...ESPECIALLY WITHIN AREAS THAT RECEIVE
WETTING RAIN. BELOW AVERAGE TEMPERATURES ARE ALSO EXPECTED TO
CONTINUE THROUGH TUESDAY...KEEPING DAYTIME HUMIDITY FAIRLY ELEVATED
THROUGH TUESDAY. SOME DAY-TO-DAY DRYING IS THEN EXPECTED WEDNESDAY
THROUGH THE END OF NEXT WEEK. THIS WILL ALLOW TEMPERATURES TO START
CLIMBING BACK TO NEAR AVERAGE FOR EARLY AUGUST.
52
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR THE FOLLOWING ZONES...
NMZ505-506-508-509-520.
&&
$$
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
140 PM EDT FRI AUG 1 2014
.SYNOPSIS...
LOOK FOR TODAY TO HAVE THE LOWEST CHANCES FOR PRECIPITATION OVER
THE COMING DAYS. THERE WILL BE JUST A SLIGHT CHANCE OF SHOWERS OR
THUNDERSTORMS OVER THE MOUNTAINS THIS AFTERNOON WITH SEASONAL
TEMPERATURES. CHANCES FOR AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS INCREASE ON SATURDAY AND SUNDAY WITH TEMPERATURES
REMAINING RIGHT AROUND SEASONAL NORMALS.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 132 PM EDT FRIDAY...GOING FORECAST IN DECENT SHAPE. AS
EXPECTED ISOLATED SHOWERS (AT THIS POINT, EXACTLY 2) HAVE
DEVELOPED -- ONE BETWEEN PLATTSBURGH AND BURLINGTON, THE OTHER
VERY NEAR ST JOHNSBURY. THESE SHOWERS ARE WITHIN AN AXIS OF
SLIGHTLY ENHANCED MOISTURE (BASED ON THE DISTRIBUTION OF CUMULUS
CLOUDS) THAT EXTENDS FROM THE ADIRONDACKS, ACROSS THE NORTHERN
THIRD OF VERMONT AND INTO EXTREME NORTHERN NEW HAMPSHIRE. THE
LATEST RUN OF THE HRRR INDICATES IT IS THIS REGION THAT ANY
ISOLATED SHOWERS WILL OCCUR OVER THE NEXT FEW HOURS. MADE SLIGHT
ADJUSTMENTS TO THE HOURLY POP FORECAST TO SHOW THIS TO BE THE
PRIMARY ZONE OF ISOLATED CONVECTION. KEPT THE WORDING AS
"THUNDERSTORM", BUT HONESTLY 12Z SOUNDINGS AS WELL AS MODEL
SOUNDINGS INDICATE A LOT OF DRY AIR ALOFT THAT SHOULD MAKE IT HARD
FOR DEEP CONVECTION TO REALLY DEVELOP, SO THUNDERSTORM MAY BE
OVERDONE. ON THE FLIP SIDE, LOCAL MESO ANALYSIS SHOWS 1000+ J/KG
CAPE VALUES IN PLACE ACROSS THE NORTHERN CHAMPLAIN VALLEY THANKS
TO TEMPERATURES AROUND 80F AND DEWPOINTS IN THE LOWER 60S.
AFTER ALL THAT TALK ABOUT CONVECTION, A SOLID 98.83% OF THE AREA
WILL REMAIN DRY TODAY. TEMPERATURES WILL PROBABLY RISE ANOTHER 3
DEGREES OR SO FROM WHERE THEY CURRENTLY ARE. ALL IN ALL, A DECENT
SUMMER DAY.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH SUNDAY/...
AS OF 419 AM EDT FRIDAY...ANY CONVECTION COMES TO AN END SHORTLY
AFTER SUNSET. FLOW ALOFT ACTUALLY BACKS JUST A BIT WHICH WILL
ALLOW FOR SOME DEEPER MOISTURE TO MOVE INTO THE REGION SATURDAY
AND SUNDAY. THE INCREASED MOISTURE WILL BRING ABOUT MORE CLOUDS ON
SATURDAY AND SUNDAY AND INSTABILITY SHOULD INCREASE DURING THIS
TIME PERIOD AS WELL. THIS SHOULD RESULT IN BETTER CHANCES FOR
AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS BOTH SATURDAY AND
SUNDAY. WEAKLY SHEARED ENVIRONMENT AND LACK OF STRONG INSTABILITY
SHOULD KEEP STORMS FROM BECOMING SEVERE WITH BRIEF HEAVY DOWNPOURS
BEING THE MAIN THREAT...ALONG WITH LIGHTNING OF COURSE. HIGH
TEMPERATURES ON SATURDAY AND SUNDAY WILL GENERALLY BE IN THE 70S
TO AROUND 80.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 419 AM EDT FRIDAY...UPPER TROUGH REMAINS OVER GREAT LAKES
REGION INTO MONDAY. WITH SOUTHWEST FLOW ALOFT AND WEAK DISTURBANCE
IN FLOW ALOFT...THERE WILL BE A LOW CHANCE FOR A FEW SHOWERS...AND
PERHAPS A THUNDERSTORM MONDAY AFTERNOON.
WE BEGIN TO SEE SOME HEIGHT FALLS TUESDAY INTO WEDNESDAY WHILE FLOW
ALOFT TURNS MORE WESTERLY. STILL SOME EMBEDDED DISTURBANCES IN THE
FLOW ALOFT. IN ADDITION...INDICATIONS THAT A WEAK SURFACE COLD FRONT
WILL MAKE ITS WAY SOUTHEAST ACROSS THE AREA DURING THIS PERIOD. THE
RESULT WILL BE A BETTER CHANCE OF SHOWERS AND PERHAPS A FEW STORMS
TUESDAY. STILL CHANCES FOR A FEW SHOWERS WEDNESDAY...AND
POSSIBLY EVEN THURSDAY...DEPENDING ON ANY LINGERING SHORTWAVES IN
FLOW ALOFT. BUT OVERALL THE TREND WILL BE TOWARDS DRIER CONDITIONS
AS FLOW BECOMES MORE NORTHWEST AND WEAK SURFACE HIGH PRESSURE BUILDS
INTO THE AREA.
TEMPERATURE PROFILES REMAIN FAIRLY UNIFORM THROUGH THE PERIOD WITH
850 MB TEMPS MOSTLY BETWEEN 12-14C MONDAY/TUESDAY...COOLING JUST A
DEGREE OR TWO WEDNESDAY/THURSDAY. WITH PARTIAL SUN...THIS SUPPORTS
VALLEY HIGHS IN THE MID 70S TO LOWER 80S...NEAR SEASONABLE LEVELS.
MIN TEMPS EXPECTED TO RANGE FROM THE 50S IN THE MOUNTAINS TO LOWER
60S IN THE VALLEYS...WITH A SLIGHT COOLING TREND BY MID WEEK
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
THROUGH 18Z SATURDAY...DIURNAL CUMULUS CLOUDS CONTINUE THIS
AFTERNOON WITH VFR CONDITIONS PREVAILING INTO THE EARLY EVENING.
A FEW ISOLATED SHOWERS WILL BE POSSIBLE THROUGH THE LATE
AFTERNOON...HAVE INCLUDED VCSH IN THE CPV.
LIGHT TO CALM WINDS AND DISSIPATING CLOUDS THIS EVENING WILL
RESULT IN LIFR/VLIFR VSBYS IN FOG AFTER 06Z SATURDAY AT KSLK AND
KMPV. VFR LOW AND MID LEVEL CLOUDS WILL INCREASE FROM THE SOUTH
AFTER 06Z...WITH DIURNAL CUMULUS CLOUDS AGAIN DEVELOPING SATURDAY
MORNING. EXPECT SCATTERED SHOWERS/STORMS TO DEVELOP IN THE LATE
MORNING/EARLY AFTERNOON...MAINLY AFTER 15Z/16Z. BRIEF PERIOD OF
MVFR MAY BE POSSIBLE WITHIN SHOWERS. WINDS WILL INCREASE TO
5-10KTS OUT OF THE SOUTH SATURDAY MORNING.
OUTLOOK 18Z SATURDAY THROUGH WEDNESDAY... MAINLY VFR ALTHOUGH
BRIEF PERIODS OF MVFR POSSIBLE IN SCATTERED SHOWERS OR
THUNDERSTORM EACH DAY WHICH WILL BE MOST LIKELY DURING THE
AFTERNOON.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...NASH
SHORT TERM...EVENSON
LONG TERM...RJS
AVIATION...KGM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
915 PM EDT SAT AUG 2 2014
.SYNOPSIS... THE COMBINATION OF A UNSEASONABLY STRONG UPPER TROUGH
AND A NEARLY STATIONARY SURFACE FRONT WILL KEEP VERY MOIST
CONDITIONS ACROSS THE REGION THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 915 PM SATURDAY...
THE CURRENT HISTORICAL WARM SEASON HYBRID COLD AIR DAMMING (CAD)
EVENT CONTINUES IN PLACE THIS EVENING. COOL ADVECTION HAS LONG
CEASED AS THE PARENT SURFACE HIGH PRESSURE CENTER SLID OFF THE MID-
ATLANTIC COAST. HOWEVER... THE SURFACE RIDGE AXIS (LOCKED IN PLACE
BY THE 24-36 HOUR MODERATE TO HEAVY RAIN EVENT) EXTENDED DIRECTLY
OVER THE HEART OF OUR PIEDMONT DAMMING REGION INTO UPSTATE SOUTH
CAROLINA AND INTO THE PIEDMONT OF GEORGIA. THE CAD BOUNDARY WAS
NEARLY STATIONARY JUST TO THE EAST AND SOUTHEAST OF OUR REGION...
EXTENDING FROM COLUMBUS COUNTY NORTHEAST TO NEAR THE WEST SIDE OF
THE ALBEMARLE SOUND. EVEN IN THE WARM SECTOR THE BOUNDARY LAYER WAS
WELL WORKED OVER BY EARLIER RAINS. BACK INLAND... INTO THE CAD
AREA... LOW OVERCAST CONDITIONS PERSISTED ALONG WITH A EVER
WEAKENING NNE FLOW.
AREAS OF LIGHT RAIN CONTINUED OVER THE EASTERN PIEDMONT AND COASTAL
PLAIN AS THE HEAVIER SHOWERS FROM EARLIER HAVE LIFTED OFF TO THE NE.
OUR REGION WAS CURRENTLY ON THE BACK SIDE OF ONE DEPARTING VORTICITY
MAXIMUM TRACKING NE IN THE SW FLOW ALOFT... WITH ANOTHER UPSTREAM
OVER THE SOUTHERN APPALACHIANS. A LINE OF CONVECTION HAS BEEN
BEARING DOWN ON THE APPALACHIANS OF SW VIRGINIA AND NW NORTH
CAROLINA. HOWEVER... WITH THE STABLE CAD DOME OVER THE REGION...
LITTLE IN THE WAY OF CONVECTION IS EXPECTED TO REACH INTO OUR NW
PIEDMONT... WHICH IS PROTECTED BY THE STABLE BOUNDARY LAYER LEFT
FROM THE CAD. THEREFORE... LITTLE GENERAL THUNDERSTORM ACTION IS
ANTICIPATED IN CENTRAL OR EASTERN NC FOR MUCH OF THE NIGHT.
HOWEVER... HI-RES MODELS DO SHOW ADDITIONAL SHOWERS AND GENERAL
THUNDERSTORMS DEVELOP/SPREAD BACK INTO THE SOUTHERN AND EASTERN
ZONES LATER TONIGHT AND SUNDAY MORNING AS THIS VORT MAX TRACKS
OVERHEAD. NOT MUCH GOING ON NOW BUT WE WILL MAINTAIN LIKELY POP
SOUTH AND EAST AND HIGH CHANCE IN THE NW ZONES OVERNIGHT. ADDITIONAL
QPF OF 0.25 TO 0.50 EXPECTED WITH LOCALLY 1+ INCH AMOUNTS EXPECTED
IN THE SE NEARER THE STATIONARY BOUNDARY. TEMPERATURES SHOULD HOLD
NEARLY STEADY AS THE CAD EVOLUTION NEARS ITS END.
AS FAR AS THE HISTORY MAKING WARM SEASON CAD FOR CENTRAL NC... NEW
RECORD EVENTS HAVE BEEN SENT. THEY INCLUDE THE FOLLOWING: THE HIGH
AT RALEIGH-DURHAM WAS 70 DEGREES. THIS SET A NEW DAILY RECORD LOW
MAXIMUM TEMPERATURE FOR AUGUST 2. THE PREVIOUS RECORD WAS 71 DEGREES
RECORDED IN 1916. THE HIGH WAS ALSO 20 DEGREES BELOW THE 30 YEAR
AVERAGE FOR RALEIGH-DURHAM. AT FAYETTEVILLE... A NEW RECORD LOW
MAXIMUM FOR AUGUST 2 WAS ALSO RECORDED WITH 72 DEGREES. THE PREVIOUS
RECORD WAS 74 DEGREES SET IN 1916. GREENSBORO RECORDED 71 DEGREES
TODAY. THEY DID NOT HAVE A NEW DAILY RECORD AS THE RECORD LOW
MAXIMUM TEMPERATURE RECORDED ON AUGUST 2 AT GREENSBORO IS 65 SET IN
1903.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 PM SATURDAY...
THE PLACEMENT OF THE UPPER TROUGH REMAINS VIRTUALLY UNCHANGED FOR
SUNDAY AND SO THERE IS NO SURPRISE THAT THE LONGER TERM MODELS ARE
VERY BULLISH ON PRODUCING PRECIPITATION. THE CONVECTIVE ALLOWING
MODELS TELL A DIFFERENT STORY HOWEVER AS THEY...AS THEY HAVE BEEN
OVER THE PAST COUPLE OF DAYS...ONLY PRODUCING SPORADIC PRECIPITATION
OVER CENTRAL NC. THE BEST FORCING WILL BE TO THE EAST AND SO THE
FOCUS FOR PRECIPIATION WILL ONCE AGAIN BE THERE BUT THERE COULD BE A
VERY SHARP GRADIENT BETWEEN GETTING A LOT OF QPF AND GETTING NONE AT
ALL. BEST CHANCES FOR RAIN WILL BE EAST OF 95 WITH DIMINISHING
CHANCES TO THE WEST. DEPENDING ON HOW WELL THE WEDGE REMAINS LOCKED
IN WILL HAVE A BIG INFLUENCE ON TEMPERATURES. THE GFS...AS IT
USUALLY DOES...SEEMS TO HAVE DESTROYED THE CAD WEDGE TOO QUICKLY
WITH A WEAK COASTAL LOW THE ONLY EROSION MECHANISM. THERE IS
HOWEVER...A SHORTWAVE MOVING THROUGH THE NORTHERN STREAM THAT COULD
HELP ERODE THE WEDGE FROM THE NORTHWEST LATE IN THE DAY. THIS
COMBINED WITH BETTER WILL BRING MUCH WARMER TEMPERATURES TO THE AREA
ON SATURDAY AFTERNOON WITH HIGHS MOST LIKELY IN THE LOW 80S BUT
POSSIBLY THE MIDDLE 80S WITH THE TRIAD BEING THE WARMEST. THERE MAY
BE A LULL IN WHATEVER PRECIPITATION OCCURS IN THE EAST OVERNIGHT
BEFORE A NEW AND STRONGER COASTAL LOW APPROACHES FROM THE SOUTH ON
MONDAY. LOWS 65 TO 70 DEGREES. -RE
FOR MON/MON NIGHT: THE SIGNIFICANT WAVE CROSSING WV LATE TONIGHT/SUN
MORNING WILL HAVE DAMPENED AND BE MOVING NE THROUGH NEW ENGLAND
EARLY MON MORNING. BUT BAGGY TROUGHING WILL LINGER OVER THE EASTERN
HALF OF THE CONUS WITH SUBTLE PERTURBATIONS SHIFTING ESE THROUGH THE
MID MISS VALLEY/OH VALLEY/MIDSOUTH... WHILE OTHERS TRACK NE THROUGH
THE ERN CAROLINAS. THE INCREASINGLY DIFFUSE SURFACE FRONTAL ZONE
OVER ERN NC IS EXPECTED TO EASE EASTWARD AND OFFSHORE THROUGH MON
NIGHT. HOWEVER... WHAT INFLUENCE NOW-TS BERTHA WILL HAVE ON THE
FRONTAL ZONE AS IT MOVES NORTHWARD WELL OFF OUR COAST REMAINS TO BE
SEEN. WE`RE LIKELY TO SEE CONTINUED ABOVE-NORMAL PW FROM THE
TRIANGLE TO THE ESE WITH LOWER VALUES TO THE WNW AS DRIER MID LEVEL
AIR IMPINGES ON THE CENTRAL/SRN APPALACHIANS... RESULTING IN HIGHER
RAIN CHANCES EAST VERSUS WEST. BUT MODEL MASS FIELDS REMAIN WILDLY
DIVERGENCE WITH A WIDE RANGE OF QPF SOLUTIONS... AND WE COULD EASILY
SEE LOWER PRECIP COVERAGE OVER CENTRAL/ERN NC DUE TO LARGE SCALE
SUBSIDENCE IN THE REGIONS SURROUNDING BERTHA`S CIRCULATION.
INTERESTINGLY THE NAM CONTINUES TO INDICATE A STRONG SURFACE LOW OFF
THE GA OR NRN FL COAST MON MORNING WHICH THEN TRACKS NE ALONG THE
CAROLINA COAST THROUGH TUE MORNING. WHILE THIS IS AN OUTLIER AMONG
THE OPERATIONAL MODELS AND APPEARS TO TAKE BERTHA`S ENERGY WESTWARD
TO ALONG THE SURFACE FRONTAL ZONE... THE NAM HAS BEEN PRETTY
CONSISTENT WITH THIS... HAS SUPPORT FROM MANY OF THE WRF-HEAVY SREF
MEMBERS... AND THERE IS INDEED EVIDENCE OF SURFACE LOW FORMATION
JUST SOUTH OF THE BAHAMAS THIS MORNING. GIVEN ALL OF THIS... WILL
STICK WITH THE GENERAL FLAVOR OF THE EXISTING POPS... GOOD CHANCES
WITH HIGHER SE THAN NW... BUT CAN`T REMOVE POPS ENTIRELY ANYWHERE AT
THIS TIME. AND IF THE NAM COMES TO FRUITION... THE PIEDMONT COULD
GET A SHOT OF HEAVY RAIN (INSTEAD OF COASTAL NC)... WITH MUCH COOLER
TEMPS. WILL FOCUS ON SHOWERS WITH ONLY ISOLATED STORMS MAINLY EAST
BASED ON SMALL FORECAST CAPE DUE IN PART TO EXPECTED EXPANSIVE
CLOUDINESS. BELOW-NORMAL HIGHS IN THE MID 80S AND LOWS 66-72. -GIH
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 305 PM SATURDAY...
FOR TUE/TUE NIGHT: FORECAST DETAILS GET INCREASINGLY MURKY BUT THE
OVERALL CONDITIONS SHOULD CHANGE LITTLE... WITH RAIN CHANCES AND
CLOUD COVER A BIT GREATER THAN USUAL (ESPECIALLY IN OUR SE)... AND
TEMPS A BIT LOWER THAN NORMAL. THE AXIS OF THE BAGGY MID LEVEL
TROUGH WILL EXTEND THROUGH CENTRAL NC AS A WEAK VORTICITY LOBE
TRANSLATES TO THE NNE THROUGH CENTRAL/ERN NC. VERY LITTLE REMAINS OF
THE SURFACE FRONTAL ZONE WITH A WEAK PRESSURE/WIND FIELD IN PLACE...
WHICH COULD LEAD TO SLOW-MOVING HEAVY SHOWERS IF ABOVE-NORMAL PW
HOLDS OVER THE AREA (AS THE GFS INDICATES). WILL MAINTAIN GOOD
CHANCE POPS... AGAIN HIGHER SE THAN NW... FOCUSED FROM MIDDAY
THROUGH MID EVENING. HIGHS 86-89. LOWS TUE NIGHT 65-70.
FOR WED-SAT: MID LEVEL FLOW WEAKENS AND FLATTENS THROUGH THE PERIOD
BUT REMAINS GENTLY CYCLONIC THROUGH FRI WITH THE UPPER LOW HOLDING
OVER ERN CANADA AND THE NORTHEAST STATES. WE SHOULD SEE ANOTHER
ROUND OF SHOWERS AND A FEW STORMS WED... MAINLY SE... BUT WITH LOWER
COVERAGE THAN EARLIER IN THE WEEK DUE TO THE WEAKER DEEP LAYER SHEAR
AND MODERATING PW. THE STRONGEST WAVE ROTATING AROUND THE BASE OF
THE MEAN TROUGH WED NIGHT (GFS) OR THU (ECMWF) IS EXPECTED TO PUSH A
WEAK COLD FRONT SOUTHEAST THROUGH NC... BRINGING A TREND BACK DOWN
TO SLIGHTLY BELOW NORMAL TEMPS LATE IN THE WEEK. WITH THE GFS AND
ECMWF ABOUT 12 HRS APART ON FRONTAL PASSAGE... IT`S TOUGH TO TELL
WHEN THE BEST FRONT-ASSOCIATED RAIN CHANCES WILL BE... SO WILL CARRY
CHANCE POPS WED NIGHT THROUGH THU... FOLLOWED BY LOWER CHANCES
FRI/SAT FIGURING THAT HIGH PRESSURE WILL BE PUSHING IN FROM THE NNW.
THE 00Z/02 ECMWF TAKES THIS HIGH OFF THE MIDATLANTIC COAST SAT WHILE
WEDGING SOUTHWARD THROUGH CENTRAL/WRN NC WITH INCREASING OVERRUNNING
AND SUGGESTIONS OF ANOTHER DAMMING EVENT NEXT WEEKEND... AND THE GFS
IS HINTING AT THIS AS WELL. WILL NOT DEPART TOO MUCH FROM
CLIMATOLOGY THIS FAR OUT... BUT STAY TUNED... AS WE COULD SEE
COOLER/WETTER WEATHER NEXT WEEKEND. -GIH
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AS OF 750 PM SATURDAY...
LOW CIGS (RANGING FROM IFR TO LOW-MVFR) CONTINUE ACROSS MUCH OF
CENTRAL NC ATTM...AND IS EXPECTED TO CONTINUE OVERNIGHT. GIVEN THE
MOIST ENVIRONMENT AND LIGHT WIND...GUIDANCE SUGGESTS IFR...AND IN
SOME CASES LIFR...FOG DEVELOPING AFTER 06Z TONIGHT AND LASTING
THROUGH 12Z SUNDAY. OTHERWISE...AFTER THE CURRENT LIGHT RAIN THATS
PRESENTLY ALONG AND EAST OF A LINE FROM KIXA TO KSOP MOVES EAST
DURING THE NEXT HOUR OR TWO...LATEST HRRR SHOWS MUCH OF CENTRAL NC
REMAINING DRY THROUGH MOST OF THE OVERNIGHT PERIOD...WITH THE BEST
CHANCE FOR ADDITIONAL RAIN LATER OVERNIGHT ALONG AND EAST OF THE I-
95 CORRIDOR. FOR THE DAYTIME SUNDAY...MODELS INDICATE SOME DRIER AIR
MOVING INTO THE WESTERN PORTION OF OUR FORECAST AREA...AND THE
DEEPER MOISTURE AND BEST RAIN CHANCES FROM KRDU EASTWARD. AS FOR
WIND...EXPECT LIGHT AND VARIABLE WIND OVERNIGHT...BECOMING EAST TO
SOUTHEAST LESS THAN 10 KT DURING THE DAY SUNDAY.
LONG TERM: UNSETTLED WEATHER CONTINUES AS THE UPPER LEVEL TROUGH
REMAINS WEST OF THE AREA FOR THE FIRST HALF OF THE WORK WEEK BEFORE
FINALLY BEGINNING TO LIFT OFF TO THE NORTHEAST BY THE END OF THE
WEEK. PRECIPITATION...AND CONSEQUENTLY AVIATION CONDITIONS...WILL
COME AND GO WITH VARIOUS SMALLER IMPULSES EXPECTED TO MOVE THROUGH
THE AREA.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH THROUGH SUNDAY EVENING FOR NCZ028-043-078-088-089.
&&
$$
SYNOPSIS...PWB
NEAR TERM...PWB
SHORT TERM...ELLIS/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...NP/ELLIS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
750 PM EDT SAT AUG 2 2014
.SYNOPSIS... UNSETTLED WEATHER WILL CONTINUE THROUGH THE WEEKEND AND
INTO EARLY NEXT WEEK AS AN UPPER LEVEL TROUGH REMAINS WEST OF THE
AREA AND A COASTAL FRONT TO THE EAST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM SATURDAY...
CENTRAL NC CONTINUES TO BE LOCKED INTO THE CAD WEDGE THIS AFTERNOON
WITH LOW CEILINGS PERSISTING. SURFACE ANALYSIS SHOWS THE COASTAL
FRONT HAS NOT MOVED MUCH AT ALL SINCE THIS MORNING AND THEREFORE THE
FOCUS FOR PRECIPIATION HAS BEEN IN THE EAST...AIDED BY A COUPLE OF
SHORT WAVES THAT MOVES THROUGH THE COASTAL PLAIN. THE FOCUS WILL
SHIFT FURTHER WEST TO CENTRAL NC AS A 500 MB VORT MAX ENTERS THE SW
CORNER OF THE CWA AND PROGRESSES NORTHEASTWARD ALONG HIGHWAY 1
QUICKLY EXITING THE AREA TO THE NORTH BY 0Z. WE HAVE ALREADY SEEN AN
UPTICK IN PRECIPITATION COVERAGE ACROSS THE AREA AND THIS SHOULD
CONTINUE FOR THE NEXT 6 HOURS OR SO. WHICH WE HAVE SEEN SOME PERIODS
OF MODERATE TO HEAVY RAIN...THERE IS A LOT OF CONVECTIVE INHIBITION
OVER THE AREA AND WHILE THERE IS A DECENT AMOUNT OF SHEAR...BETWEEN
THE LOW TEMPERATURES AND POOR INSTABILITY...FIND IT HARD TO BELIEVE
THAT WE WILL SEE MUCH IN THE WAY OF SEVERE WEATHER TODAY. THEREFORE
THE FOCUS WILL REMAIN ON THE HEAVY RAIN AND POTENTIAL URBAN AND
SMALL STREAM FLOODING THAT MAY BE POSSIBLE THIS EVENING AS UPWARDS
OF 1 TO 2 INCHES OF RAIN COULD BE POSSIBLE IN SOME SPOTS. MOST AREAS
HAVE STRUGGLED TO GET OUT OF THE 60S TODAY WITH THE SOUTH AND EAST
FINALLY BREAKING INTO THE LOWER 70S. TEMPS SHOULD NOT GET MUCH
HIGHER THAN THEY ARE NOW...PERHAPS A DEGREE OR TWO SO WILL GO WITH
HIGHS IN THE LOW TO MID 70S.
TONIGHT EXPECT ANOTHER UNSETTLED EVENING WITH SEVERAL SMALLER
IMPULSES GENERATING SOME SHOWER ACTIVITY OVERNIGHT BEFORE A NEW
PERTURBATION BRINGS HEAVIER RAIN BACK TO EASTERN NC EARLY SUNDAY
MORNING. EXPECT PROLONGED PERIODS OF REDUCED VISIBILITY AND CEILINGS
LESS THAN 500 FEET THROUGH SUNRISE. LOWS IN THE MID 60S NW TO UPPER
60S TO NEAR 70 IN THE SE.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 PM SATURDAY...
THE PLACEMENT OF THE UPPER TROUGH REMAINS VIRTUALLY UNCHANGED FOR
SUNDAY AND SO THERE IS NO SURPRISE THAT THE LONGER TERM MODELS ARE
VERY BULLISH ON PRODUCING PRECIPITATION. THE CONVECTIVE ALLOWING
MODELS TELL A DIFFERENT STORY HOWEVER AS THEY...AS THEY HAVE BEEN
OVER THE PAST COUPLE OF DAYS...ONLY PRODUCING SPORADIC PRECIPITATION
OVER CENTRAL NC. THE BEST FORCING WILL BE TO THE EAST AND SO THE
FOCUS FOR PRECIPIATION WILL ONCE AGAIN BE THERE BUT THERE COULD BE A
VERY SHARP GRADIENT BETWEEN GETTING A LOT OF QPF AND GETTING NONE AT
ALL. BEST CHANCES FOR RAIN WILL BE EAST OF 95 WITH DIMINISHING
CHANCES TO THE WEST. DEPENDING ON HOW WELL THE WEDGE REMAINS LOCKED
IN WILL HAVE A BIG INFLUENCE ON TEMPERATURES. THE GFS...AS IT
USUALLY DOES...SEEMS TO HAVE DESTROYED THE CAD WEDGE TOO QUICKLY
WITH A WEAK COASTAL LOW THE ONLY EROSION MECHANISM. THERE IS
HOWEVER...A SHORTWAVE MOVING THROUGH THE NORTHERN STREAM THAT COULD
HELP ERODE THE WEDGE FROM THE NORTHWEST LATE IN THE DAY. THIS
COMBINED WITH BETTER WILL BRING MUCH WARMER TEMPERATURES TO THE AREA
ON SATURDAY AFTERNOON WITH HIGHS MOST LIKELY IN THE LOW 80S BUT
POSSIBLY THE MIDDLE 80S WITH THE TRIAD BEING THE WARMEST. THERE MAY
BE A LULL IN WHATEVER PRECIPITATION OCCURS IN THE EAST OVERNIGHT
BEFORE A NEW AND STRONGER COASTAL LOW APPROACHES FROM THE SOUTH ON
MONDAY. LOWS 65 TO 70 DEGREES. -RE
FOR MON/MON NIGHT: THE SIGNIFICANT WAVE CROSSING WV LATE TONIGHT/SUN
MORNING WILL HAVE DAMPENED AND BE MOVING NE THROUGH NEW ENGLAND
EARLY MON MORNING. BUT BAGGY TROUGHING WILL LINGER OVER THE EASTERN
HALF OF THE CONUS WITH SUBTLE PERTURBATIONS SHIFTING ESE THROUGH THE
MID MISS VALLEY/OH VALLEY/MIDSOUTH... WHILE OTHERS TRACK NE THROUGH
THE ERN CAROLINAS. THE INCREASINGLY DIFFUSE SURFACE FRONTAL ZONE
OVER ERN NC IS EXPECTED TO EASE EASTWARD AND OFFSHORE THROUGH MON
NIGHT. HOWEVER... WHAT INFLUENCE NOW-TS BERTHA WILL HAVE ON THE
FRONTAL ZONE AS IT MOVES NORTHWARD WELL OFF OUR COAST REMAINS TO BE
SEEN. WE`RE LIKELY TO SEE CONTINUED ABOVE-NORMAL PW FROM THE
TRIANGLE TO THE ESE WITH LOWER VALUES TO THE WNW AS DRIER MID LEVEL
AIR IMPINGES ON THE CENTRAL/SRN APPALACHIANS... RESULTING IN HIGHER
RAIN CHANCES EAST VERSUS WEST. BUT MODEL MASS FIELDS REMAIN WILDLY
DIVERGENCE WITH A WIDE RANGE OF QPF SOLUTIONS... AND WE COULD EASILY
SEE LOWER PRECIP COVERAGE OVER CENTRAL/ERN NC DUE TO LARGE SCALE
SUBSIDENCE IN THE REGIONS SURROUNDING BERTHA`S CIRCULATION.
INTERESTINGLY THE NAM CONTINUES TO INDICATE A STRONG SURFACE LOW OFF
THE GA OR NRN FL COAST MON MORNING WHICH THEN TRACKS NE ALONG THE
CAROLINA COAST THROUGH TUE MORNING. WHILE THIS IS AN OUTLIER AMONG
THE OPERATIONAL MODELS AND APPEARS TO TAKE BERTHA`S ENERGY WESTWARD
TO ALONG THE SURFACE FRONTAL ZONE... THE NAM HAS BEEN PRETTY
CONSISTENT WITH THIS... HAS SUPPORT FROM MANY OF THE WRF-HEAVY SREF
MEMBERS... AND THERE IS INDEED EVIDENCE OF SURFACE LOW FORMATION
JUST SOUTH OF THE BAHAMAS THIS MORNING. GIVEN ALL OF THIS... WILL
STICK WITH THE GENERAL FLAVOR OF THE EXISTING POPS... GOOD CHANCES
WITH HIGHER SE THAN NW... BUT CAN`T REMOVE POPS ENTIRELY ANYWHERE AT
THIS TIME. AND IF THE NAM COMES TO FRUITION... THE PIEDMONT COULD
GET A SHOT OF HEAVY RAIN (INSTEAD OF COASTAL NC)... WITH MUCH COOLER
TEMPS. WILL FOCUS ON SHOWERS WITH ONLY ISOLATED STORMS MAINLY EAST
BASED ON SMALL FORECAST CAPE DUE IN PART TO EXPECTED EXPANSIVE
CLOUDINESS. BELOW-NORMAL HIGHS IN THE MID 80S AND LOWS 66-72. -GIH
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 305 PM SATURDAY...
FOR TUE/TUE NIGHT: FORECAST DETAILS GET INCREASINGLY MURKY BUT THE
OVERALL CONDITIONS SHOULD CHANGE LITTLE... WITH RAIN CHANCES AND
CLOUD COVER A BIT GREATER THAN USUAL (ESPECIALLY IN OUR SE)... AND
TEMPS A BIT LOWER THAN NORMAL. THE AXIS OF THE BAGGY MID LEVEL
TROUGH WILL EXTEND THROUGH CENTRAL NC AS A WEAK VORTICITY LOBE
TRANSLATES TO THE NNE THROUGH CENTRAL/ERN NC. VERY LITTLE REMAINS OF
THE SURFACE FRONTAL ZONE WITH A WEAK PRESSURE/WIND FIELD IN PLACE...
WHICH COULD LEAD TO SLOW-MOVING HEAVY SHOWERS IF ABOVE-NORMAL PW
HOLDS OVER THE AREA (AS THE GFS INDICATES). WILL MAINTAIN GOOD
CHANCE POPS... AGAIN HIGHER SE THAN NW... FOCUSED FROM MIDDAY
THROUGH MID EVENING. HIGHS 86-89. LOWS TUE NIGHT 65-70.
FOR WED-SAT: MID LEVEL FLOW WEAKENS AND FLATTENS THROUGH THE PERIOD
BUT REMAINS GENTLY CYCLONIC THROUGH FRI WITH THE UPPER LOW HOLDING
OVER ERN CANADA AND THE NORTHEAST STATES. WE SHOULD SEE ANOTHER
ROUND OF SHOWERS AND A FEW STORMS WED... MAINLY SE... BUT WITH LOWER
COVERAGE THAN EARLIER IN THE WEEK DUE TO THE WEAKER DEEP LAYER SHEAR
AND MODERATING PW. THE STRONGEST WAVE ROTATING AROUND THE BASE OF
THE MEAN TROUGH WED NIGHT (GFS) OR THU (ECMWF) IS EXPECTED TO PUSH A
WEAK COLD FRONT SOUTHEAST THROUGH NC... BRINGING A TREND BACK DOWN
TO SLIGHTLY BELOW NORMAL TEMPS LATE IN THE WEEK. WITH THE GFS AND
ECMWF ABOUT 12 HRS APART ON FRONTAL PASSAGE... IT`S TOUGH TO TELL
WHEN THE BEST FRONT-ASSOCIATED RAIN CHANCES WILL BE... SO WILL CARRY
CHANCE POPS WED NIGHT THROUGH THU... FOLLOWED BY LOWER CHANCES
FRI/SAT FIGURING THAT HIGH PRESSURE WILL BE PUSHING IN FROM THE NNW.
THE 00Z/02 ECMWF TAKES THIS HIGH OFF THE MIDATLANTIC COAST SAT WHILE
WEDGING SOUTHWARD THROUGH CENTRAL/WRN NC WITH INCREASING OVERRUNNING
AND SUGGESTIONS OF ANOTHER DAMMING EVENT NEXT WEEKEND... AND THE GFS
IS HINTING AT THIS AS WELL. WILL NOT DEPART TOO MUCH FROM
CLIMATOLOGY THIS FAR OUT... BUT STAY TUNED... AS WE COULD SEE
COOLER/WETTER WEATHER NEXT WEEKEND. -GIH
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AS OF 750 PM SATURDAY...
LOW CIGS (RANGING FROM IFR TO LOW-MVFR) CONTINUE ACROSS MUCH OF
CENTRAL NC ATTM...AND IS EXPECTED TO CONTINUE OVERNIGHT. GIVEN THE
MOIST ENVIRONMENT AND LIGHT WIND...GUIDANCUE SUGGESTS IFR...AND IN
SOME CASES LIFR...FOG DEVELOPING AFTER 06Z TONIGHT AND LASTING
THROUGH 12Z SUNDAY. OTHERWISE...AFTER THE CURRENT LIGHT RAIN THATS
PRESENTLY ALONG AND EAST OF A LINE FROM KIXA TO KSOP MOVES EAST
DURING THE NEXT HOUR OR TWO...LATEST HRRR SHOWS MUCH OF CENTRAL NC
REMAINING DRY THROUGH MOST OF THE OVERNIGHT PERIOD...WITH THE BEST
CHANCE FOR ADDITIONAL RAIN LATER OVERNIGHT ALONG AND EAST OF THE I-
95 CORRIDOR. FOR THE DAYTIME SUNDAY...MODELS INDICATE SOME DRIER AIR
MOVING INTO THE WESTERN PORTION OF OUR FORECAST AREA...AND THE
DEEPER MOISTURE AND BEST RAIN CHANCES FROM KRDU EASTWARD. AS FOR
WIND...EXPECT LIGHT AND VARIABLE WIND OVERNIGHT...BECOMING EAST TO
SOUTHEAST LESS THAN 10 KT DURING THE DAY SUNDAY.
LONG TERM: UNSETTLED WEATHER CONTINUES AS THE UPPER LEVEL TROUGH
REMAINS WEST OF THE AREA FOR THE FIRST HALF OF THE WORK WEEK BEFORE
FINALLY BEGINNING TO LIFT OFF TO THE NORTHEAST BY THE END OF THE
WEEK. PRECIPITATION...AND CONSEQUENTLY AVIATION CONDITIONS...WILL
COME AND GO WITH VARIOUS SMALLER IMPULSES EXPECTED TO MOVE THROUGH
THE AREA.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH THROUGH SUNDAY EVENING FOR NCZ028-043-078-088-089.
&&
$$
SYNOPSIS...ELLIS
NEAR TERM...ELLIS
SHORT TERM...ELLIS/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...NP/ELLIS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
126 AM EDT FRI AUG 1 2014
.SYNOPSIS...
A COASTAL FRONT JUST OFFSHORE WILL PUSH INLAND ON FRIDAY...THEN
SHOULD STALL OVER THE AREA DURING THE WEEKEND. THIS WILL BRING
GOOD RAIN CHANCES...WITH PERIODS OF HEAVY RAINFALL POSSIBLE FRIDAY
THROUGH MONDAY. MORE SEASONABLE WEATHER WILL DEVELOP THE MIDDLE OF
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1:30 AM FRIDAY...SCATTERED SHOWERS WITH A FEW EMBEDDED
THUNDERSTORMS ONGOING ACROSS THE FORECAST AREA. MOISTURE TAP SEEMS
TO BE GRADUALLY SHIFTING EASTWARDS. FORECAST UPDATED ACCORDINGLY.
PREVIOUS DISCUSSION FOLLOWS:
SEVERAL THINGS HAVE TRANSPIRED (OR IS IT CONSPIRED?) OVER THE FEW
HOURS TO CHANGE THE FORECAST PRETTY DRAMATICALLY. A MOIST CONVEYOR
ORIGINATING FROM THE EDGE OF THE GULF STREAM OFF THE SOUTH
CAROLINA COAST IS FEEDING INTO GEORGETOWN COUNTY AND HAS ITS EYES
FIXED ON THE I-95 CORRIDOR/PEE DEE REGION FOR THE NEXT FEW HOURS.
JUST GIVEN THE OBSERVED TRAJECTORY ON RADAR THIS MOISTURE IS
ENCOUNTERING RATHER SIGNIFICANT ISENTROPIC ASCENT AS IT MOVES UP
INTO THE IN-SITU COLD DOME IN PLACE ACROSS THE CENTRAL CAROLINAS.
EVEN THOUGH THE 00Z CHS SOUNDING SHOWED DRY AIR ABOVE 700 MB AND A
PRECIPITABLE WATER VALUE OF ONLY 1.55 INCHES...AMSU + SSM/I BLENDED
TOTAL PRECIPITABLE WATER SATELLITE DATA HAD A RELATIVE MAXIMUM
ACROSS THE SANTEE RIVER INTO THE PEE DEE REGION OF 1.9 INCHES. THIS
IS CO-LOCATED WITH THE HEAVY RAINFALL BAND OBSERVED ON RADAR. I HAVE
INCREASED AREAL AVERAGE RAINFALL FORECASTS TO AROUND 0.75 INCHES
ACROSS FLORENCE AND MARION NORTHWARD INTO DILLON AND BENNETTSVILLE
OVERNIGHT...WITH THE EXPECTATION THAT ISOLATED AREAS WILL SEE 2 TO
2.5 INCHES. THE HAZARDOUS WEATHER OUTLOOK HAS BEEN UPDATED WITH THE
POTENTIAL FOR MINOR FLOODING OVERNIGHT AS WELL. OBVIOUSLY FORECAST
POPS ACROSS THIS CORRIDOR ARE 100 PERCENT.
THE HRRR IS TOO FAR WEST WITH THE CURRENT CONVECTIVE ACTIVITY...BUT
SHOWS THAT ONCE THIS HEAVY RAIN MOVES NORTHWARD INTO CENTRAL NORTH
CAROLINA THE NEXT WAVE OF CONVECTION MAY DEVELOP OVER THE COASTAL
WATERS OFF THE SC COAST MOVING NORTHWARD INTO COASTAL SE NORTH
CAROLINA AROUND OR SHORTLY AFTER DAYBREAK.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY NIGHT/...
AS OF 230 PM THURSDAY...PERIOD CONTINUES TO LOOK UNSETTLED WITH
INCREASING DEEP MOISTURE AND DEVELOPING LOW LEVEL CONVERGENCE. MID
LEVEL TROUGH HANGING OVER THE EASTERN CONUS THE PAST SEVERAL DAYS
STARTS TO WEAKEN AND SHIFT WEST AS 5H RIDGE OVER THE WESTERN
ATLANTIC EXPANDS. MEANWHILE AT THE SURFACE WESTERN ATLANTIC HIGH
WILL EXTEND WEST...PUSHING FRONT STALLED OFF THE COAST INTO THE
REGION. DEEP SOUTHWEST FLOW...TAPPING GULF MOISTURE...COMBINED
WITH LOW LEVEL SOUTHEAST FLOW...TAPPING ATLANTIC MOISTURE...WILL
PUSH PRECIPITABLE WATER VALUES TO AND ABOVE 2 INCHES FOR MUCH OF
THE PERIOD. DIVERGENT FLOW ALOFT AND LOW LEVEL CONVERGENCE ALONG
THE QUASI-STATIONARY BOUNDARY IN A MODERATELY UNSTABLE ENVIRONMENT
SHOULD PRODUCE PLENTY OF SHOWERS AND THUNDERSTORMS. NOT
ANTICIPATING ANY WIDESPREAD STRONG TO SEVERE STORMS BUT GIVEN THE
TIME OF YEAR CANNOT RULE OUT AN ISOLATED STRONGER STORM. ALTHOUGH
THERE IS LIKELY TO BE A DIURNAL INCREASE IN ACTIVITY PRECIP
CHANCES WILL REMAIN ELEVATED OVERNIGHT GIVEN FAVORABLE CONDITIONS.
HIGH TEMPERATURES WILL CONTINUE TO RUN BELOW CLIMO WITH CLOUD COVER
AND PRECIP KEEPING HIGHS IN THE LOW TO MID 80S. SOUTHERLY
FLOW...INCREASING MOISTURE...AND CLOUD COVER WILL KEEP LOWS NEAR TO
SLIGHTLY ABOVE CLIMO...LOW TO MID 70S.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 230 PM THURSDAY...ATYPICALLY WELL DEFINED (FOR THE TIME OF
YEAR) MID AND UPPER LEVEL TROUGHINESS TO OUR WEST ON SUNDAY.
DECAYING SURFACE BOUNDARY TO PROVIDE LOW LEVEL LIFT...WHICH WILL
THEN BE AIDED BY MID LEVEL PVA AND UPPER DIVERGENCE ASSOC WITH
RIGHT ENTRANCE OF UPPER JET STREAK ACROSS NORTHEAST AND MID
ATLANTIC. AND WHILE RAIN CHANCES SEEM TO WARRANT LIKELY POPS
MODELS ARE NOT SUGGESTIVE OF HIGH QPF AMOUNTS. THIS MAY BE DUE TO
IT BEING SUCH A CLOUDY DAY THAT VERY LITTLE INSTABILITY MANAGES TO
DEVELOP SAVE FOR PERHAPS ALONG THE IMMEDIATE COAST. THESE PLAYERS
ALL REMAIN NEARLY IN PLACE HEADING INTO MONDAY ALTHOUGH ALL OF
THEM WEAKEN. LOOKING FOR ANOTHER DAY OF HIGH POPS AND SUPPRESSED
AFTERNOON TEMPS. TUESDAY SHOULD BRING LOWER RAIN CHANCES BUT STILL
ONES THAT ARE HIGHER THAN NORMAL. THE UPPER JET CONTINUES TO
WEAKEN AND LIFT OUT TO THE NORTHEAST WHILE THE MID LEVEL TROUGH
WEAKENS...BUT ALSO SENDS ITS REMAINING VORT CENTER ACROSS THE
CAROLINAS. IN RESPONSE TO THIS THE GFS STRAIGHTENS THE PIEDMONT
TROUGH AT THE SURFACE. WE ALSO MAY SEE A BIT MORE SUNSHINE IN
CONTRAST TO THE EARLY PARTS OF THE PERIOD. TUESDAY MAY THUS BE A
DAY WHERE WE TRANSITION TO MORE SCATTERED AND DEEPER CONVECTION
ESP IF TEMPS START BOUNCING BACK TOWARDS CLIMO. WEDNESDAY AND
THURSDAY LOOK SEASONABLE WITH RESPECT TO BOTH TEMPERATURES AND
AREAL COVERAGE OF CONVECTION. MID LEVEL FLOW SHOULD BE OF A DRIER
WESTERLY DIRECTION WHILE SOME SEMBLANCE OF A PIEDMONT TROUGH
REMAINS.
&&
.AVIATION /05Z FRIDAY THROUGH TUESDAY/...
AS OF 06Z...SHOWERS WILL BE LIKELY THIS TAF VALID PERIOD AT ALL
TERMINALS. THUNDERSTORMS WILL BE POSSIBLE THIS MORNING NEAR THE
COASTAL TERMINALS...THEN RE-DEVELOP THIS AFTERNOON ACROSS MAINLY
INLAND LOCATIONS. TEMPO PERIODS OF MVFR CAN BE EXPECTED WITH THE
ACTIVITY. DUE TO THE QUICK MOVEMENT OF CELLS ONLY BRIEF PERIODS OF
IFR EXPECTED. WINDS WILL BE E-ESE AROUND 10KT...EXCEPT VRBL TO 20
KT NEAR CONVECTION. RADAR AND SATELLITE TRENDS SUGGEST THAT THE
COASTAL TERMINALS WILL BE MOST LIKELY TO EXPERIENCE SHRA/TEMPO
MVFR THROUGH SUNRISE. SHOWERS AT THE COASTAL TERMINALS SHOULD END
12-15Z. LIGHT RA SHOULD END OVER THE NEXT SEVERAL HOURS AT
KFLO/KLBT. MVFR CIGS/VSBYS SHOULD DEVELOP AFTERWARDS AT KFLO/KLBT
AND PERSIST THROUGH SUNRISE.
EXTENDED OUTLOOK...SHRA/TSRA LIKELY WITH PERIODS OF MVFR
CONDITIONS THROUGH MON AS A FRONT STALLS AND FINALLY DISSIPATES
OVER THE EASTERN CAROLINAS. A CHANCE OF SHOWERS CONTINUES ON TUE.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1:30 PM FRIDAY...NO CHANGES TO THE FORECAST WITH THE LATEST
UPDATE. PREVIOUS DISCUSSION FOLLOWS:
THE PINCHED PRESSURE GRADIENT ALONG THE WEST SIDE OF THE COASTAL
TROUGH/WARM FRONT OFFSHORE HAS PUSHED WIND SPEEDS TO 20 KNOTS WITH
GUSTS AS HIGH AS 24 KNOTS ALONG THE HORRY COUNTY SC COAST EARLIER.
THIS IS STRONGER THAN ANY MODEL INDICATED...AND THIS MOST-RECENT
FORECAST UPDATE IS BASED MORE ON CURRENT OBSERVATIONS THAN ANY
COMPUTER MODEL. EAST WINDS AROUND 20 KNOTS SHOULD BEGIN TO
DIMINISH AROUND 2-3 AM AS THE FRONT GETS A LITTLE CLOSER TO THE
COAST AND THE BAGGIER PRESSURE GRADIENT SURROUNDING THE BOUNDARY
ARRIVES. SEAS HAVE RESPONDED TO THE HIGHER WIND SPEEDS WITH 5 FEET
SHOWING UP AT THE NEARSHORE WRIGHTSVILLE BEACH CORMP BUOY. THIS IS
A FULL 3 FEET HIGHER THAN FORECASTS JUST SIX HOURS AGO AND SHOWS
HOW QUICKLY CONDITIONS HAVE DETERIORATED HERE. AN EXERCISE CAUTION
HEADLINE HAS BEEN ADDED TO THE FORECAST THROUGH 3 AM FOR ALL
WATERS.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 230 PM THURSDAY...PERIOD WILL BE DOMINATED BY SOUTHEAST
FLOW AS FRONT STALLED OFFSHORE MOVES TO THE COAST FRI THEN PUSHES
ONSHORE SAT. GRADIENT WILL BE WEAK FOR MUCH OF THE PERIOD WITH THE
ONLY POSSIBLE EXCEPTION DURING FRI NIGHT WHEN GRADIENT SHARPENS AS
BOUNDARY BECOMES A LITTLE MORE DEFINED. SPEEDS FRI NIGHT MAY TOUCH
15 KT BUT OTHERWISE SPEEDS WILL BE ON THE LOWER END OF THE 10 TO
15 KT RANGE. SEAS 2 TO 3 FT EARLY IN THE PERIOD INCREASE TO A
SOLID 3 FT GIVEN THE PROLONGED SOUTHEAST WINDS AND DEVELOPMENT OF
EAST-SOUTHEAST WIND WAVE.
LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 230 PM THURSDAY...LIGHT SOUTHERLY WINDS ON SUNDAY WITH
FRONTAL BOUNDARY JUST INLAND OF THE COAST. WIND CHOP WILL BE
COINCIDENT WITH 11 SECOND SOUTHEASTERLY SWELL. THE WEAKENING
BOUNDARY WILL MOVE FURTHER INLAND FOR THE REMAINDER OF THE PERIOD
AND THE WEST ATLANTIC HIGH POKES A BIT WESTWARD FURTHER INTO THE
CAROLINAS. THIS COULD LEAD TO AN OCCASIONAL INCREASE IN FLOW BY A
FEW KNOTS AND ALSO A SLIGHT VEER FROM S TO SW.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...III
NEAR TERM...REK/TRA/SGL
SHORT TERM...III
LONG TERM...MBB
AVIATION...MRR
MARINE...REK/TRA/III/MBB/SGL
AREA FORECAST DISCUSSION
NWS BISMARCK ND
134 PM CDT FRI AUG 1 2014
.UPDATE...
ISSUED AT 134 PM CDT FRI AUG 1 2014
FORECAST REMAINS VALID THROUGH THE AFTERNOON/EVENING. AREA OF
SHOWERS AND ISOLATED THUNDERSTORMS CONTINUE TO TRACK SOUTHEAST
ACROSS WESTERN NORTH DAKOTA AS A MID LEVEL EMBEDDED IMPULSE MOVES
THROUGH ALOFT. THIS FEATURE MAY TRIGGER ADDITIONAL CONVECTION THIS
AFTERNOON/EVENING SOUTHWEST AND SOUTH CENTRAL NEAR ITS PROXIMITY
AND ALONG A STATIONARY BOUNDARY MENTIONED IN THE PREVIOUS
DISCUSSION. ANOTHER EMBEDDED S/WV CAN BE SEEN SPINNING OVER
SOUTHWESTERN SASKATCHEWAN...WHICH IS PROJECTED TO CONTINUE SOUTH
AND EAST INTO NORTHWEST/NORTH CENTRAL ND LATER THIS EVENING AND
OVERNIGHT...SPARKING ADDITIONAL SHOWERS/THUNDERSTORMS WHICH LOOK
TO CONTINUE PAST DAYBREAK SAT MORNING OVER PORTIONS OF
CENTRAL/EASTERN ND.
UPDATE
ISSUED AT 955 AM CDT FRI AUG 1 2014
SURFACE LOW PRESSURE CENTERED NEAR SOUTHWEST NORTH DAKOTA...WITH
A FRONTAL BOUNDARY STRETCHED FROM WESTERN SOUTH DAKOTA BACK
NORTHWEST ACROSS EASTERN MONTANA. NORTHWEST FLOW ALOFT WITH A MID
LEVEL S/WV IMPULSE MOVING SLOWLY SOUTHEAST ACROSS EASTERN MONTANA
IS INTERACTING WITH THIS BOUNDARY TO TRIGGER A FEW
SHOWERS/ISOLATED THUNDERSTORMS OVER MY FAR WESTERN COUNTIES.
ADDITIONAL MID LEVEL IMPULSES WILL PUSH THROUGH ALOFT
TODAY/TONIGHT. WITH THE FRONTAL BOUNDARY REMAINING QUASI-
STATIONARY...WILL CONTINUE TO MENTION A CHANCE OF
PRECIPITATION...WEST AND SOUTH THIS EVENING...NORTH OVERNIGHT.
WHILE WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED...WILL HAVE
ENOUGH INSTABILITY AND SUFFICIENT 0-6KM SHEAR FOR THE POSSIBILITY
OF A FEW ORGANIZED UPDRAFTS AND THUS A SMALL THREAT FOR LARGE
HAIL. ALSO...CIGS AT AROUND 8-10K FEET AGL WILL ELEVATE THE CHANCE
FOR A FEW STRONGER WIND GUSTS WITH ANY STORMS.
UPDATE ISSUED AT 643 AM CDT FRI AUG 1 2014
NO SIGNIFICANT CHANGES REQUIRED WITH THIS UPDATE OTHER THAN TO
BLEND TO THE 1130 UTC OBSERVED TRENDS AS THE INHERITED FORECAST IS
IN LINE WITH THE 06 UTC GFS/NAM AND 08-09 UTC HRRR ITERATIONS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM CDT FRI AUG 1 2014
CURRENTLY...A SURFACE LOW WAS OVER EASTERN MONTANA WHILE BROAD HIGH
PRESSURE STRETCHES FROM MANITOBA THROUGH THE EASTERN DAKOTAS INTO
THE MINNESOTA. AT UPPER LEVELS A RIDGE EXTENDED FROM THE GREAT BASIN
INTO THE NORTHERN ROCKIES WHILE AN UPPER LEVEL LOW SPINS NEAR JAMES
BAY BRINGING NORTH-NORTHWESTERLY FLOW TO OUR AREA WITH A VARIETY OF
WEAK IMPULSES SLIDING THROUGH.
A SMALL CLUSTER OF THUNDERSTORMS OVER SOUTH CENTRAL SASKATCHEWAN...IN
THE SWIFT CURRENT AREA...CONTINUED TO SUSTAIN ITS CONVECTION THROUGH
THE EARLY MORNING HOURS. THE MODELS DEPICT A WEAK UPPER LEVEL
IMPULSE IN THE AREA WHERE CURRENT THUNDERSTORM ACTIVITY WAS
OCCURRING. THE NAM DEPICTS THE WEAK UPPER LEVEL IMPULSE MOVING
SOUTHEASTWARD SLOWLY...APPROACHING NORTHWESTERN NORTH DAKOTA
BEFORE/AROUND DAYBREAK...THEN MOVING THROUGH SOUTHWESTERN NORTH
DAKOTA FRIDAY AFTERNOON.
LATER TODAY...THE MODELS INDICATE THE EASTERN MONTANA SURFACE LOW
DEVELOPS SOUTHWARD AND AN EAST-WEST SURFACE FRONTAL BOUNDARY BECOMES
ESTABLISHED OVER NORTHERN SOUTH DAKOTA. THIS SURFACE BOUNDARY
COMBINED WITH WEAK UPPER LEVEL IMPULSES MOVING THROUGH THE
NORTHWESTERLY FLOW ALOFT SHOULD RESULT IN BETTER CHANCES OF
CONVECTION IN SOUTH DAKOTA...THUS WILL KEEP THE MENTION OF SLIGHT
CHANCE OF THUNDERSTORMS ACROSS THE SOUTH.
FRIDAY NIGHT...THE UPPER LEVEL IMPULSE AND ASSOCIATED SURFACE
BOUNDARY IN SOUTH DAKOTA MOVES FARTHER SOUTH. ATTENTION THEN TURNS
TO THE NEXT UPPER LEVEL IMPULSE MOVING SOUTHEASTWARD OUT OF
SASKATCHEWAN. THIS FEATURE APPROACHES NORTHWESTERN NORTH DAKOTA
FRIDAY EVENING...AND IS PROGGED TO REACH THE CENTRAL DAKOTAS AFTER
MIDNIGHT. WILL KEEP SLIGHT CHANCES OF THUNDERSTORMS NORTHWEST THIS
EVENING...WITH ISOLATED TO SCATTERED CHANCES LATE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 333 AM CDT FRI AUG 1 2014
A MORE ACTIVE WEATHER PATTERN WILL HIGHLIGHT THE EXTENDED FORECAST.
THE 00 UTC DETERMINISTIC AND ENSEMBLE SUITES ARE IN GOOD AGREEMENT
ON AN UPPER LEVEL RIDGE CENTERED ACROSS THE INTERMOUNTAIN WEST
THIS WEEKEND...SLOWLY BREAKING DOWN WITH A TRANSITION TO NEAR
ZONAL FLOW EARLY NEXT WEEK. THIS SUPPORTS DAILY CHANCES FOR
THUNDERSTORMS ASSOCIATED WITH IMPULSES PROPAGATING ALONG THE
NORTHERN PERIPHERY OF THE RIDGE AND EMBEDDED WITHIN THE ZONAL
FLOW. CERTAINLY CANNOT RULE OUT AN ISOLATED SEVERE THREAT EACH DAY
SUNDAY THROUGH WEDNESDAY...HOWEVER...A WIDESPREAD SEVERE THREAT
IS NOT EXPECTED AT THIS TIME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 134 PM CDT FRI AUG 1 2014
A SMALL CLUSTER OF SHOWERS/THUNDERSTORMS CONTINUES SOUTHEAST
ACROSS WESTERN ND...AND MAY IMPACT KDIK 20-22Z. OTHERWISE VFR
CONDITIONS EXPECTED THROUGH THE FORECAST PERIOD. ADDITIONAL
ISOLATED STORMS ARE FORECAST LATE THIS AFTERNOON AND EVENING
ACROSS WESTERN AND SOUTH CENTRAL NORTH DAKOTA. HOWEVER...GIVEN LOW
COVERAGE...DIRECT IMPACTS TO ANY ONE TERMINAL ARE UNLIKELY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...JV
LONG TERM...AYD
AVIATION...NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
955 AM CDT FRI AUG 1 2014
.UPDATE...
ISSUED AT 955 AM CDT FRI AUG 1 2014
SURFACE LOW PRESSURE CENTERED NEAR SOUTHWEST NORTH DAKOTA...WITH
A FRONTAL BOUNDARY STRETCHED FROM WESTERN SOUTH DAKOTA BACK
NORTHWEST ACROSS EASTERN MONTANA. NORTHWEST FLOW ALOFT WITH A MID
LEVEL S/WV IMPULSE MOVING SLOWLY SOUTHEAST ACROSS EASTERN MONTANA
IS INTERACTING WITH THIS BOUNDARY TO TRIGGER A FEW
SHOWERS/ISOLATED THUNDERSTORMS OVER MY FAR WESTERN COUNTIES.
ADDITIONAL MID LEVEL IMPULSES WILL PUSH THROUGH ALOFT
TODAY/TONIGHT. WITH THE FRONTAL BOUNDARY REMAINING QUASI-
STATIONARY...WILL CONTINUE TO MENTION A CHANCE OF
PRECIPITATION...WEST AND SOUTH THIS EVENING...NORTH OVERNIGHT.
WHILE WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED...WILL HAVE
ENOUGH INSTABILITY AND SUFFICIENT 0-6KM SHEAR FOR THE POSSIBILITY
OF A FEW ORGANIZED UPDRAFTS AND THUS A SMALL THREAT FOR LARGE
HAIL. ALSO...CIGS AT AROUND 8-10K FEET AGL WILL ELEVATE THE CHANCE
FOR A FEW STRONGER WIND GUSTS WITH ANY STORMS.
UPDATE ISSUED AT 643 AM CDT FRI AUG 1 2014
NO SIGNIFICANT CHANGES REQUIRED WITH THIS UPDATE OTHER THAN TO
BLEND TO THE 1130 UTC OBSERVED TRENDS AS THE INHERITED FORECAST IS
IN LINE WITH THE 06 UTC GFS/NAM AND 08-09 UTC HRRR ITERATIONS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM CDT FRI AUG 1 2014
CURRENTLY...A SURFACE LOW WAS OVER EASTERN MONTANA WHILE BROAD HIGH
PRESSURE STRETCHES FROM MANITOBA THROUGH THE EASTERN DAKOTAS INTO
THE MINNESOTA. AT UPPER LEVELS A RIDGE EXTENDED FROM THE GREAT BASIN
INTO THE NORTHERN ROCKIES WHILE AN UPPER LEVEL LOW SPINS NEAR JAMES
BAY BRINGING NORTH-NORTHWESTERLY FLOW TO OUR AREA WITH A VARIETY OF
WEAK IMPULSES SLIDING THROUGH.
A SMALL CLUSTER OF THUNDERSTORMS OVER SOUTH CENTRAL SASKATCHEWAN...IN
THE SWIFT CURRENT AREA...CONTINUED TO SUSTAIN ITS CONVECTION THROUGH
THE EARLY MORNING HOURS. THE MODELS DEPICT A WEAK UPPER LEVEL
IMPULSE IN THE AREA WHERE CURRENT THUNDERSTORM ACTIVITY WAS
OCCURRING. THE NAM DEPICTS THE WEAK UPPER LEVEL IMPULSE MOVING
SOUTHEASTWARD SLOWLY...APPROACHING NORTHWESTERN NORTH DAKOTA
BEFORE/AROUND DAYBREAK...THEN MOVING THROUGH SOUTHWESTERN NORTH
DAKOTA FRIDAY AFTERNOON.
LATER TODAY...THE MODELS INDICATE THE EASTERN MONTANA SURFACE LOW
DEVELOPS SOUTHWARD AND AN EAST-WEST SURFACE FRONTAL BOUNDARY BECOMES
ESTABLISHED OVER NORTHERN SOUTH DAKOTA. THIS SURFACE BOUNDARY
COMBINED WITH WEAK UPPER LEVEL IMPULSES MOVING THROUGH THE
NORTHWESTERLY FLOW ALOFT SHOULD RESULT IN BETTER CHANCES OF
CONVECTION IN SOUTH DAKOTA...THUS WILL KEEP THE MENTION OF SLIGHT
CHANCE OF THUNDERSTORMS ACROSS THE SOUTH.
FRIDAY NIGHT...THE UPPER LEVEL IMPULSE AND ASSOCIATED SURFACE
BOUNDARY IN SOUTH DAKOTA MOVES FARTHER SOUTH. ATTENTION THEN TURNS
TO THE NEXT UPPER LEVEL IMPULSE MOVING SOUTHEASTWARD OUT OF
SASKATCHEWAN. THIS FEATURE APPROACHES NORTHWESTERN NORTH DAKOTA
FRIDAY EVENING...AND IS PROGGED TO REACH THE CENTRAL DAKOTAS AFTER
MIDNIGHT. WILL KEEP SLIGHT CHANCES OF THUNDERSTORMS NORTHWEST THIS
EVENING...WITH ISOLATED TO SCATTERED CHANCES LATE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 333 AM CDT FRI AUG 1 2014
A MORE ACTIVE WEATHER PATTERN WILL HIGHLIGHT THE EXTENDED FORECAST.
THE 00 UTC DETERMINISTIC AND ENSEMBLE SUITES ARE IN GOOD AGREEMENT
ON AN UPPER LEVEL RIDGE CENTERED ACROSS THE INTERMOUNTAIN WEST
THIS WEEKEND...SLOWLY BREAKING DOWN WITH A TRANSITION TO NEAR
ZONAL FLOW EARLY NEXT WEEK. THIS SUPPORTS DAILY CHANCES FOR
THUNDERSTORMS ASSOCIATED WITH IMPULSES PROPAGATING ALONG THE
NORTHERN PERIPHERY OF THE RIDGE AND EMBEDDED WITHIN THE ZONAL
FLOW. CERTAINLY CANNOT RULE OUT AN ISOLATED SEVERE THREAT EACH DAY
SUNDAY THROUGH WEDNESDAY...HOWEVER...A WIDESPREAD SEVERE THREAT
IS NOT EXPECTED AT THIS TIME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 643 AM CDT FRI AUG 1 2014
A SMALL CLUSTER OF THUNDERSTORMS THAT ENTERED NORTHEASTERN MONTANA
FROM SASKATCHEWAN WILL CONTINUE TO MOVE TOWARDS KISN. STORMS COULD
DIMINISH GREATLY AFTER 13Z-15Z. OTHERWISE VFR CONDITIONS EXPECTED
THROUGH THE FORECAST PERIOD. ADDITIONAL ISOLATED STORMS ARE
FORECAST LATE THIS AFTERNOON AND EVENING ACROSS WESTERN AND SOUTH
CENTRAL NORTH DAKOTA. HOWEVER...GIVEN LOW COVERAGE...DIRECT IMPACTS
TO ANY ONE TERMINAL ARE UNLIKELY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...JV
LONG TERM...AYD
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
647 AM CDT FRI AUG 1 2014
.UPDATE...
ISSUED AT 643 AM CDT FRI AUG 1 2014
NO SIGNIFICANT CHANGES REQUIRED WITH THIS UPDATE OTHER THAN TO
BLEND TO THE 1130 UTC OBSERVED TRENDS AS THE INHERITED FORECAST IS
IN LINE WITH THE 06 UTC GFS/NAM AND 08-09 UTC HRRR ITERATIONS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM CDT FRI AUG 1 2014
CURRENTLY...A SURFACE LOW WAS OVER EASTERN MONTANA WHILE BROAD HIGH
PRESSURE STRETCHES FROM MANITOBA THROUGH THE EASTERN DAKOTAS INTO
THE MINNESOTA. AT UPPER LEVELS A RIDGE EXTENDED FROM THE GREAT BASIN
INTO THE NORTHERN ROCKIES WHILE AN UPPER LEVEL LOW SPINS NEAR JAMES
BAY BRINGING NORTH-NORTHWESTERLY FLOW TO OUR AREA WITH A VARIETY OF
WEAK IMPULSES SLIDING THROUGH.
A SMALL CLUSTER OF THUNDERSTORMS OVER SOUTH CENTRAL SASKATCHEWAN...IN
THE SWIFT CURRENT AREA...CONTINUED TO SUSTAIN ITS CONVECTION THROUGH
THE EARLY MORNING HOURS. THE MODELS DEPICT A WEAK UPPER LEVEL
IMPULSE IN THE AREA WHERE CURRENT THUNDERSTORM ACTIVITY WAS
OCCURRING. THE NAM DEPICTS THE WEAK UPPER LEVEL IMPULSE MOVING
SOUTHEASTWARD SLOWLY...APPROACHING NORTHWESTERN NORTH DAKOTA
BEFORE/AROUND DAYBREAK...THEN MOVING THROUGH SOUTHWESTERN NORTH
DAKOTA FRIDAY AFTERNOON.
LATER TODAY...THE MODELS INDICATE THE EASTERN MONTANA SURFACE LOW
DEVELOPS SOUTHWARD AND AN EAST-WEST SURFACE FRONTAL BOUNDARY BECOMES
ESTABLISHED OVER NORTHERN SOUTH DAKOTA. THIS SURFACE BOUNDARY
COMBINED WITH WEAK UPPER LEVEL IMPULSES MOVING THROUGH THE
NORTHWESTERLY FLOW ALOFT SHOULD RESULT IN BETTER CHANCES OF
CONVECTION IN SOUTH DAKOTA...THUS WILL KEEP THE MENTION OF SLIGHT
CHANCE OF THUNDERSTORMS ACROSS THE SOUTH.
FRIDAY NIGHT...THE UPPER LEVEL IMPULSE AND ASSOCIATED SURFACE
BOUNDARY IN SOUTH DAKOTA MOVES FARTHER SOUTH. ATTENTION THEN TURNS
TO THE NEXT UPPER LEVEL IMPULSE MOVING SOUTHEASTWARD OUT OF
SASKATCHEWAN. THIS FEATURE APPROACHES NORTHWESTERN NORTH DAKOTA
FRIDAY EVENING...AND IS PROGGED TO REACH THE CENTRAL DAKOTAS AFTER
MIDNIGHT. WILL KEEP SLIGHT CHANCES OF THUNDERSTORMS NORTHWEST THIS
EVENING...WITH ISOLATED TO SCATTERED CHANCES LATE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 333 AM CDT FRI AUG 1 2014
A MORE ACTIVE WEATHER PATTERN WILL HIGHLIGHT THE EXTENDED FORECAST.
THE 00 UTC DETERMINISTIC AND ENSEMBLE SUITES ARE IN GOOD AGREEMENT
ON AN UPPER LEVEL RIDGE CENTERED ACROSS THE INTERMOUNTAIN WEST
THIS WEEKEND...SLOWLY BREAKING DOWN WITH A TRANSITION TO NEAR
ZONAL FLOW EARLY NEXT WEEK. THIS SUPPORTS DAILY CHANCES FOR
THUNDERSTORMS ASSOCIATED WITH IMPULSES PROPAGATING ALONG THE
NORTHERN PERIPHERY OF THE RIDGE AND EMBEDDED WITHIN THE ZONAL
FLOW. CERTAINLY CANNOT RULE OUT AN ISOLATED SEVERE THREAT EACH DAY
SUNDAY THROUGH WEDNESDAY...HOWEVER...A WIDESPREAD SEVERE THREAT
IS NOT EXPECTED AT THIS TIME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 643 AM CDT FRI AUG 1 2014
A SMALL CLUSTER OF THUNDERSTORMS THAT ENTERED NORTHEASTERN MONTANA
FROM SASKATCHEWAN WILL CONTINUE TO MOVE TOWARDS KISN. STORMS COULD
DIMINISH GREATLY AFTER 13Z-15Z. OTHERWISE VFR CONDITIONS EXPECTED
THROUGH THE FORECAST PERIOD. ADDITIONAL ISOLATED STORMS ARE
FORECAST LATE THIS AFTERNOON AND EVENING ACROSS WESTERN AND SOUTH
CENTRAL NORTH DAKOTA. HOWEVER...GIVEN LOW COVERAGE...DIRECT IMPACTS
TO ANY ONE TERMINAL ARE UNLIKELY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...JV
LONG TERM...AYD
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
753 PM EDT SAT AUG 2 2014
.SYNOPSIS...
AN UPPER LEVEL LOW CROSSES TONIGHT INTO SUNDAY. WEAK HIGH PRESSURE
PASSES EARLY NEXT WEEK. A COLD FRONT CROSSES MID WEEK. A STRONGER
HIGH THEN BUILDS IN TO CLOSE OUT THE WORK WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
600 PM UPDATE...
EARLY UPDATE TO ADJUST TO CATEGORICAL POPS WITH THE MAIN LINE OF
SHOWERS AND THUNDERSTORMS THIS EVENING...AND TO BETTER TIME THE
LINE AS IT CROSSES WEST TO EAST. STORMS SHOWING SIGNS OF
WEAKENING...AND EXPECT THIS TREND TO CONTINUE AS THEY CONTINUE
EASTWARD THIS EVENING...WITH LESS INSTABILITY NOTED FURTHER EAST
OF THE I79 CORRIDOR.
PREVIOUS DISCUSSION...
THE HRRR SEEMS TO HAVE THE BEST HANDLE ON WHAT IS CURRENTLY GOING
ON ALTHOUGH NONE OF THE MODELS SEEM TO BE GRASPING WHAT APPEARS TO
BE A LINE OF SHOWERS AND THUNDERSTORMS JUST AHEAD OF AN UPPER
LEVEL TROUGH APPROACHING THE MIDDLE OHIO VALLEY. THAT TROUGH
BECOMES A CLOSED LOW AT TIMES AS IT MOVES ACROSS TONIGHT. IT THEN
OPENS UP AND PULLS OUT OF THE AREA ON SUNDAY.
HAVE THE ASSOCIATED CONVECTION WANING WITH THE SUNSET TONIGHT...THEN
REFIRING A BIT DURING THE HEATING OF THE DAY SUNDAY...BEFORE
TRENDING DRIER FROM THE W LATE IN THE DAY...AS THE SYSTEM BEGINS
PULLING OUT OF THE AREA. WILL HAVE TO WATCH THE SLOWER CELL
MOVEMENT AS THE FLOW IN THE COLUMN WEAKENS UNDERNEATH THE UPPER
LEVEL TROUGH AXIS.
TEMPERATURES LOOKED GOOD IN LIGHT OF THE LATEST GUIDANCE.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
SHORTWAVE ENERGY PUSHES OFF TO THE EAST BEGINNING OF THE
PERIOD...WITH DRIER WEATHER AS HIGH PRESSURE BUILDS IN. FLOW WILL
TURN MORE SOUTHEASTERLY LATER IN THE DAY MONDAY...WITH UPSLOPE
SHOWERS POSSIBLE OVER THE HIGHER TERRAIN COUNTIES.
UNSETTLED WEATHER WILL RETURN TO THE AREA TUESDAY THROUGH THURSDAY
AS A FRONTAL BOUNDARY SAGS SOUTH ACROSS THE AREA. STILL SOME
TIMING...PLACEMENT DIFFERENCES AMONG THE MODELS...AND FOLLOWED THE
TREND OF THE ECMWF IN TERMS OF POPS...WHICH IS SLOWER...AND NOT AS
COOL AS THE GFS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
UNCERTAINTY EXISTS IN THE LONG TERM PERIOD CONCERNING THE SOUTHWARD
EXTENT OF A FRONTAL BOUNDARY MID WEEK...AND THE APPROACH OF ANOTHER
SYSTEM...THAT SHOULD AFFECT THE AREA TOWARDS THE END OF THE PERIOD.
KEPT A BROAD BRUSH OF POPS...AND OVERALL UNSETTLED WEATHER TREND
DURING THE EXTENDED PERIOD.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
00Z SUNDAY THROUGH 00Z MONDAY...
A NEARLY SOLID LINE OF SHOWERS AND THUNDERSTORMS CURRENTLY
STRETCHING FROM NEAR CKB SSW-WARD TO NEAR BKW WILL CONTINUE TO
SLOWLY PROGRESS EASTWARD...AND CLEAR THE EASTERN MOUNTAINS IN THE
NEXT 3-4 HOURS. EVEN NOW...THE INTENSITY OF THE THUNDERSTORMS IS
DIMINISHING AND SHOULD CONTINUE TO DO SO. BUT VERY HEAVY RAINFALL
RATES AND GUSTY WINDS ARE STILL POSSIBLE. ANOTHER AREA OF LIGHT
SHOWERS IS CURRENTLY PUSHING SE-WARD ACROSS SOUTH-CENTRAL
OHIO...BUT THIS IS EXPECTED TO WEAKEN AND EVENTUALLY DISSIPATE OVER
THE NEXT FEW HOURS WITH MINIMAL IMPACTS TO SOUTHWEST PARTS OF THE
AREA.
IN THE WAKE OF THE PRECIP...DENSE VALLEY FOG IS LIKELY OVERNIGHT
INTO SUNDAY MORNING. MVFR STRATOCU MAY ALSO SHOW UP OVER EASTERN
WV TONIGHT.
SUNDAY WILL BE A MAINLY VFR DAY ONCE THE FOG BURNS OFF...AS THE
UPPER LEVEL TROUGH PULLS OUT OF THE AREA...WITH ISOLATED TO
SCATTERED CONVECTION MOVING EWD.
FLOW SFC AND ALOFT WILL BE LIGHT AND VARIABLE...BECOMING LIGHT NW
ALOFT OVERNIGHT AND SUNDAY.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z MONDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING AND EXTENT OF FOG MAY VARY...ALTHOUGH
CONFIDENCE IN DENSE FOG IS GENERALLY HIGH.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SUN 08/03/14
UTC 1HRLY 00 01 02 03 04 05 06 07 08 09 10 11
EDT 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07
CRW CONSISTENCY M H H M M L L L L L L L
HTS CONSISTENCY H H H M H H L L L L L L
BKW CONSISTENCY H M M M H H H H H H L M
EKN CONSISTENCY M M H L L L L L L L L L
PKB CONSISTENCY M H H H M H L L L L L L
CKB CONSISTENCY M M H M M M L L L L L L
AFTER 00Z MONDAY...
VLIFR IN DENSE RIVER VALLEY FOG OVERNIGHT AND EARLY MONDAY MORNING
AS FOG SEASON IS UPON US...AND WEAK HIGH PRESSURE BUILDS ACROSS
THE AREA EARLY NEXT WEEK.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/RPY/30
NEAR TERM...TRM/50
SHORT TERM...SL
LONG TERM...SL
AVIATION...50
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
142 AM EDT FRI AUG 1 2014
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN WEDGED ACROSS THE AREA TO THE
EAST OF THE MOUNTAINS THROUGH THE WEEKEND AS AN UPPER TROUGH
CONTINUES OVER THE EASTERN STATES. TO THE EAST...A FRONT WILL REMAIN
NEARLY STATIONARY ALONG THE COAST. ATLANTIC MOISTURE WILL CONTINUE
TO SPREAD INTO THE AREA WHICH WILL FUEL WIDESPREAD SHOWERS AND A FEW
THUNDERSTORMS. SOME LOCALLY HEAVY RAINFALL IS LIKELY. CONDITIONS ARE
EXPECTED TO RETURN TO MORE TYPICAL LATE SUMMER WEATHER BY THE MIDDLE
OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
130 AM EDT UPDATE...PRECIP SHIELD AROUND IS SHIFTING JUST ENOUGH TO
PRECLUDE MUCH OF A HYDRO THREAT THIS MORNING. SOME CELLS ARE
PRODUCING INSTANTANEOUS RATES ON THE ORDER OF 1 IN/HR OVER THE EAST
CENTRAL UPSTATE...BUT 3-HR FFG RATIOS REMAIN 50 PERCENT OR LESS PER
DUAL POL. THE 02Z HRRR HAS INITIALIZED PRETTY WELL WITH THE LLVL MASS
FIELDS AND WILL LEAN TOWARD THE GENERAL IDEA OF THE PRECIP FOCUS
ALIGNING ALONG THE BLUE RIDGE AND NC FOOTHILLS OVER THE NEXT SEVERAL
HRS. THE OP MODELS ALSO HAVE THIS SAME GENERAL QPF TREND. THERE
COULD BE ENUF RAINFALL ACROSS THE CENTRAL UPSTATE TO WARRANT AN SPS
OR POSSIBLY AN ADVISORY OVER THE NEXT FEW HRS....ESP OVER AREAS THAT
RECEIVED HIGH AMOUNTS YESTERDAY. POPS WERE CUT BACK SIGFNTLY ACROSS
THE FAR WRN ZONES WHERE VERY SHALLOW MOISTURE IS CURRENTLY WORKING
IN. TEMPS AND TDS ARE IN GOOD SHAPE WITH STEADY STATE CONDS.
1015 PM UPDATE...WIDESPREAD LIGHT RAIN EXTENDS IN A SHIELD FROM
METRO ATLANTA NEWD INTO THE CENTRAL NC PIEDMONT...ON THE COOL SIDE
OF THE FIXED BOUNDARY ACROSS THE LOWER SC MIDLANDS. SELY FLOW
CONTINUES OVER THE BOUNDARY WITH PWAT VALUES HAVING STEADILY
INCREASED TODAY AS A RESULT. THIS SHOULD CONTINUE OVERNIGHT AND
LATEST GUIDANCE STILL FEATURES INCREASING PRECIP RATES ACRS THE CWFA
INTO EARLY FRIDAY. CONVECTION HAS WANED WITHIN THE RAIN SHIELD OVER
THE PAST COUPLE HRS THOUGH 00Z KGSO RAOB SUGGESTS FAIRLY STRONG
LAPSE RATES REMAIN ABOVE THE NOCTURNAL INVERSION. THIS BACKS UP THE
EXPECTATION THAT WE WILL SEE INCREASING AMOUNTS OF PRECIP OVERNIGHT
WITH SHORTWAVE ENERGY APPROACHING FROM THE GULF STATES. FLOOD THREAT
CURRENTLY IS RATHER LOW WITH HRLY RATES OF ONE OR TWO TENTHS PER
HOUR AT MOST SITES. WITHOUT CONVECTION IT IS UNLIKELY FLASH FLOODING
WILL OCCUR...BUT THE LONG DURATION OF RAIN IN AREAS WHICH RECEIVED
HEAVY RAIN EARLIER WILL LIKELY BECOME A CONCERN. PORTIONS OF
ANDERSON AND GREENVILLE COUNTIES GOT 4-6 INCHES OF RAIN THIS AFTN
AND THESE AREAS WILL BE CLOSELY MONITORED.
IN GENERAL...RAISED POPS UNDERNEATH THE CONTIGUOUS AREA OF
PRECIP...HOLDING ONTO CATEGORICAL WORDING UNTIL AFTER MIDNIGHT WHEN
UPSLOPING IS SUGGESTED TO INCREASE ITS INFLUENCE. TEMPS ARE TRICKY
WITH HRLY TRENDS SUGGESTIVE OF RAIN COOLING...BUT I REVISED
OVERNIGHT TRENDS/LOWS BASED ON THE LATEST OBS AND LAMP TRENDS.
AS OF 210 PM EDT...A POSITIVELY TILTED UPPER TROUGH WILL REMAIN FROM
EASTERN CANADA TO THE GULF COAST TODAY AND TONIGHT. A SHORTWAVE
TROUGH ROUNDING THE BASE OF THIS TROUGH WILL CROSS THE SOUTHERN
APPALACHIANS TONIGHT...AND THE FOOTHILLS AND PIEDMONT ON FRIDAY. LOW
LEVEL UPSLOPE FLOW IS SHOWN TO INCREASE IN MODEL TIME HEIGHTS...
WITH ISENTROPIC UPGLIDE INCREASING AS WELL.
THE COMBINATION OF THESE INGREDIENTS WILL SUPPORT HEAVY
RAINFALL...ESPECIALLY LATE TONIGHT AND EARLY FRIDAY. THE GREATEST
RAINFALL POTENTIAL WILL BE ALONG AND NEAR THE BLUE RIDGE. WITH
ROBUST ANTECEDENT RAINFALL ON THE SC FOOTHILLS...THAT AREA WILL BE
ESPECIALLY VULNERABLE TO FLOODING. THE FLASH FLOOD WATCH FORM AREAS
WEST OF THE INTERSTATE 77 CORRIDOR WILL REMAIN IN PLACE THROUGH
FRIDAY MORNING.
INSTABILITY WILL BE SUFFICIENT FOR CONVECTION...MAINLY DURING
MAXIMUM DAYTIME HEATING EACH AFTERNOON. MODEL SOUNDINGS INDICATE
THAT THERE MAY BE A BRIEF PEAK OF ELEVATED INSTABILITY LATE TONIGHT
AS THE SHORTWAVE MOVES OVERHEAD. THIS OVERNIGHT PEAK APPEARS TO
COINCIDE WITH SOME LOW LEVEL SHEAR...BUT THE TWO INDICES DO NOT
APPEAR TO OVERLAP IN HEIGHT. THE DIURNAL TEMPERATURE RANGE WILL BE
LIMITED BY MOISTURE AND CLOUDS COVER.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY/...
AT 2 PM EDT THURSDAY...THE WET PATTERN WILL CONTINUE THROUGH THE
WEEKEND. AN UPPER TROUGH WILL REMAIN WEST OF THE APPALACHIANS WHICH
WILL SEND A SERIES OF IMPULSES THROUGH THE AREA. AT THE SURFACE...
AN OSCILLATING QUASI-STATIONARY FRONT WILL REMAIN JUST EAST OF THE
AREA AS WAVES OF LOW PRESSURE RIPPLE NE ALONG IT. ALSO...ISENTROPIC
LIFT WILL CONTINUE OVER A WEDGE BOUNDARY LOCATED ALONG THE EAST
SLOPES OF THE MOUNTAIN CHAIN. THERE MAY BE A LULL/DOWN TICK IN
COVERAGE OF RAIN EARLY SATURDAY EAST OF THE MOUNTAINS AS A WAVE OF
LOW PRESSURE INDUCES THE FRONT TO MOVE EASTWARD SOMEWHAT. HOWEVER...
GUIDANCE POPS REMAIN HIGH SO EXPECT THAT AREAS OF RAIN/DRIZZLE WILL
REMAIN AND UPSLOPE FLOW IN THE MOUNTAINS WILL CONTINUE TO PRODUCE
EVEN MORE WIDESPREAD SHOWER COVERAGE THERE. ANOTHER WAVE ON THE
FRONT IS LIKELY TO DEVELOP BY SUN MORNING OVER EASTERN SC WHICH WILL
PRODUCE INCREASED ISENTROPIC UPGLIDE AND MORE WIDESPREAD SHOWERS SAT
NIGHT THROUGH SUN. PW`S WILL REMAIN ELEVATED THROUGH THE PERIOD...SO
AREAS OF HEAVY RAINFALL ARE A GOOD BET. RAINFALL IN THE 1-2 INCH
RANGE IS LIKELY MOST PLACES....WITH LOCALLY HEAVIER AMOUNTS. MAX
TEMPS WILL REMAIN WELL BELOW NORMAL.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 1220 AM FRIDAY...THIS MEDIUM RANGE PERIOD BEGINNING AT 12Z
MONDAY WITH THE UPPER AIR PATTERN WITH A TROUGH AXIS WEST OF THE
APPALACHIANS. THIS TROUGH WILL GRADUALLY TRANSITION INTO MORE ZONAL
WEST TO EAST FLOW IN MID WEEK. AS THE TROUGH BREAKS DOWN...A WEAK
UPPER LOW WILL BE LEFT OVER THE LOWER MISSISSIPPI VALLEY. AS THE
GENERAL WESTERLY FLOW INCREASES IN MID WEEK...OUR AIRMASS WILL
BECOME DRIER AND TEMPS WILL RETURN TO NEAR NORMAL. ON MONDAY...THE
STALLED OUT SURFACE FRONT FROM NRN FL TO ALONG THE CAROLINA COAST
WILL HAVE WEAK LOWS RIDING NE ALONG THE FRONT. IT APPEARS THE
TROPICAL LOW BERTHA IS FORECAST TO BE EAST OF THE CAROLINAS OUT
TOWARD BERMUDA ON TUESDAY AS IT TURNS FROM NW TO N THEN NE AVOIDING
THE EAST COAST. BY WED AND THUR WE CAN EXPECT A TYPICAL SUMMERTIME
PATTERN OF PM TSTORMS FAVORING THE MTNS WITH LESS OUT OVER THE
PIEDMONT. SOME UPPER ENERGY WILL BE APPROACHING FROM THE NW LATE
THURS...BUT MOST EFFECTS SHOULD HOLD OFF UNTIL AFTER THE END OF THE
CURRENT FORECAST.
MONDAY HIGH TEMPS WILL BE AROUND 7 DEGREES BELOW NORMAL THEN REBOUND
TO NEAR NORMAL WED AND THURS.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AT KCLT...LIGHT TO MODERATE RAIN SHIELD WILL CONTINUE TO COME AND GO
AT CLT THIS MORNING AND A GRADUAL LOWERING OF CIGS TO IFR ARND 10Z.
NOT MUCH IMPROVEMENT TIL 15Z OR SO AS SFC HEATING WILL BE SLOW. THE
TAF REMAINS PESSIMISTIC WITH MVFR CIGS EXPECTED MOST OF THE DAY THEN
A DROP BACK IFR LATE ARND 03Z. THUNDER CHANCES REMAIN HIGH ENOUGH
FOR PROB30 MENTION AFT 18Z.
ELSEWHERE...A MIXED BAG OF CIGS/VSBY THIS MORNING DEPENDING ON THE
INTENSITY AND LOCATION OF RAINFALL. ALL SITES SHOULD DROP TO LOW
MVFR IF NOT IFR THIS MORNING MAINLY FOR CIGS. KAND WILL SEE THE
QUICKEST IMPROVEMENT BY 15Z TO POSSIBLY VFR CONDS AS PRECIP SHIELD
PUSHES NORTH. OTHER SITES WILL LIKELY TEMPO MVFR/VFR THROUGH THE
DAY...WITH LOWERING CIGS TO IFR LATE IN THE TAF PERIOD. THUNDER
CHANCES REMAIN HIGH ENOUGH FOR PROB30S AND VCTS THIS AFTERNOON.
OUTLOOK...UNSETTLED WEATHER WITH ENHANCED PRECIPITATION CHANCES
ALONG WITH MORNING FOG/STRATUS ARE EXPECTED THROUGH THE WEEKEND.
CONFIDENCE TABLE...
05-11Z 11-17Z 17-23Z 23-05Z
KCLT MED 71% MED 78% HIGH 94% HIGH 80%
KGSP HIGH 89% MED 76% HIGH 86% MED 69%
KAVL MED 78% HIGH 80% MED 76% MED 78%
KHKY HIGH 82% HIGH 80% HIGH 99% HIGH 91%
KGMU HIGH 86% MED 72% HIGH 85% MED 71%
KAND HIGH 85% MED 73% MED 67% MED 69%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FLASH FLOOD WATCH UNTIL NOON EDT TODAY FOR GAZ010-017-018-026-
028-029.
NC...FLASH FLOOD WATCH UNTIL NOON EDT TODAY FOR NCZ033-048>053-058-
059-062>065-501>510.
SC...FLASH FLOOD WATCH UNTIL NOON EDT TODAY FOR SCZ001>007-010>012-
019.
&&
$$
SYNOPSIS...LG
NEAR TERM...JAT/WIMBERLEY/SBK
SHORT TERM...LG
LONG TERM...LG
AVIATION...SBK
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
1218 PM CDT FRI AUG 1 2014
.UPDATE...
UPDATE TO 18Z AVIATION DISCUSSION BELOW.
ONLY SOME MINOR CHANGES TO THE FORECAST FOR TODAY. BASED ON MOST
RECENT HRRR RUNS AND 12Z DATA COMING IN...IT APPEARS LESS LIKELY
THAT ANY ISOLATED STORMS WILL GET GOING ACROSS THE EASTERN
COUNTIES THIS AFTERNOON....ALTHOUGH CANNOT BE COMPLETELY RULED
OUT. MOST LIKELY SCENARIO APPEARS TO FAVOR AFTERNOON DEVELOPMENT
ACROSS WESTERN SD AND MOVING INTO CENTRAL SD BY THIS EVENING. THIS
WILL FORM IN VICINITY OF WEAK SFC LOW AND SFC BOUNDARY OVER
WESTERN SD. CURRENT HIGHS APPEAR ON TRACK AND LITTLE CHANGES
NEEDED THERE.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TODAY THROUGH SUNDAY
UPPER LEVEL RIDGING WILL REMAIN IN PLACE OVER THE WESTERN PART OF
THE COUNTRY THROUGH THE SHORT TERM PERIOD. WILL SEE SOME WEAK
ENERGY RIDE OVER THE RIDGE AND ACROSS THE CWA TODAY...THEN AGAIN
SATURDAY NIGHT OVER THE NORTHEASTERN CWA. WEAK SURFACE LOW
PRESSURE WILL BE OVER THE AREA...BUT WITH NO REAL SIGNIFICANT
BOUNDARY AROUND. THEREFORE...WILL ONCE AGAIN JUST SEE SOME
ISOLATED SHOWERS OR WEAK THUNDERSTORMS DEVELOP DUE TO DAYTIME
HEATING...MAINLY ACROSS THE WESTERN CWA WHERE WEAK INSTABILITY
DEVELOPS.
WITH NO REAL UPPER SUPPORT LATE TONIGHT AND SATURDAY...EXPECT
MAINLY DRY CONDITIONS...THEN WILL REINTRODUCE SMALL POPS TO THE
NORTHEASTERN CWA IN ASSOCIATION WITH THE UPPER WAVE SATURDAY
NIGHT. SUNDAY LOOKS TO BE PRETTY MUCH DRY AS THE WAVE TRACKS AWAY
FROM THE AREA.
NEAR TO SLIGHTLY ABOVE NORMAL TEMPERATURES WILL CONTINUE THROUGH
THE SHORT TERM PERIOD...WITH HIGHS MAINLY IN THE MID 80S ACROSS
THE EAST...AND IN THE UPPER 80S TO LOWER 90S ACROSS THE WEST.
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
MID LEVEL RIDGING OVER THE ROCKIES SHOULD GRADUALLY DE-AMPLIFY AS
ENERGY MAKES ITS WAY THROUGH THE RIDGE AND FLATTENS IT. THERE ARE
CHANCES FOR CONVECTION JUST ABOUT EVERY PERIOD OF THE LONG
TERM...HOWEVER THE BEST OPPORTUNITY LOOKS TO BE ABOUT TUESDAY
NIGHT THROUGH WEDNESDAY AS MORE CONSOLIDATED LOOKING ENERGY WILL
BE ABLE TO INTERACT WITH A NEARLY STATIONARY BOUNDARY ACROSS THE
REGION. THUS POPS ARE HIGHEST FOR THIS TIME PERIOD. THE REST OF
THE TIME WILL FEATURE HIT AND MISS RAIN CHANCES. TEMPERATURES WILL
PROBABLY START OUT NEAR OR ABOVE NORMAL AT THE BEGINNING OF THE
PERIOD...THEN TREND TO NEAR OR BELOW NORMAL BY THE MIDDLE OF NEXT
WEEK.
&&
.AVIATION...
18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
VFR CONDITIONS ARE EXPECTED THIS AFTERNOON AND OVERNIGHT.
ISOLATED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE ACROSS CENTRAL
SOUTH DAKOTA...ESPECIALLY AROUND KPIR AND KMBG.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...TMT
SHORT TERM...PARKIN
LONG TERM...TDK
AVIATION...SCARLETT
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1106 AM CDT FRI AUG 1 2014
.UPDATE...REST OF TODAY
ONLY SOME MINOR CHANGES TO THE FORECAST FOR TODAY. BASED ON MOST
RECENT HRRR RUNS AND 12Z DATA COMING IN...IT APPEARS LESS LIKELY
THAT ANY ISOLATED STORMS WILL GET GOING ACROSS THE EASTERN
COUNTIES THIS AFTERNOON....ALTHOUGH CANNOT BE COMPLETELY RULED
OUT. MOST LIKELY SCENARIO APPEARS TO FAVOR AFTERNOON DEVELOPMENT
ACROSS WESTERN SD AND MOVING INTO CENTRAL SD BY THIS EVENING. THIS
WILL FORM IN VICINITY OF WEAK SFC LOW AND SFC BOUNDARY OVER
WESTERN SD. CURRENT HIGHS APPEAR ON TRACK AND LITTLE CHANGES
NEEDED THERE.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TODAY THROUGH SUNDAY
UPPER LEVEL RIDGING WILL REMAIN IN PLACE OVER THE WESTERN PART OF
THE COUNTRY THROUGH THE SHORT TERM PERIOD. WILL SEE SOME WEAK
ENERGY RIDE OVER THE RIDGE AND ACROSS THE CWA TODAY...THEN AGAIN
SATURDAY NIGHT OVER THE NORTHEASTERN CWA. WEAK SURFACE LOW
PRESSURE WILL BE OVER THE AREA...BUT WITH NO REAL SIGNIFICANT
BOUNDARY AROUND. THEREFORE...WILL ONCE AGAIN JUST SEE SOME
ISOLATED SHOWERS OR WEAK THUNDERSTORMS DEVELOP DUE TO DAYTIME
HEATING...MAINLY ACROSS THE WESTERN CWA WHERE WEAK INSTABILITY
DEVELOPS.
WITH NO REAL UPPER SUPPORT LATE TONIGHT AND SATURDAY...EXPECT
MAINLY DRY CONDITIONS...THEN WILL REINTRODUCE SMALL POPS TO THE
NORTHEASTERN CWA IN ASSOCIATION WITH THE UPPER WAVE SATURDAY
NIGHT. SUNDAY LOOKS TO BE PRETTY MUCH DRY AS THE WAVE TRACKS AWAY
FROM THE AREA.
NEAR TO SLIGHTLY ABOVE NORMAL TEMPERATURES WILL CONTINUE THROUGH
THE SHORT TERM PERIOD...WITH HIGHS MAINLY IN THE MID 80S ACROSS
THE EAST...AND IN THE UPPER 80S TO LOWER 90S ACROSS THE WEST.
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
MID LEVEL RIDGING OVER THE ROCKIES SHOULD GRADUALLY DE-AMPLIFY AS
ENERGY MAKES ITS WAY THROUGH THE RIDGE AND FLATTENS IT. THERE ARE
CHANCES FOR CONVECTION JUST ABOUT EVERY PERIOD OF THE LONG
TERM...HOWEVER THE BEST OPPORTUNITY LOOKS TO BE ABOUT TUESDAY
NIGHT THROUGH WEDNESDAY AS MORE CONSOLIDATED LOOKING ENERGY WILL
BE ABLE TO INTERACT WITH A NEARLY STATIONARY BOUNDARY ACROSS THE
REGION. THUS POPS ARE HIGHEST FOR THIS TIME PERIOD. THE REST OF
THE TIME WILL FEATURE HIT AND MISS RAIN CHANCES. TEMPERATURES WILL
PROBABLY START OUT NEAR OR ABOVE NORMAL AT THE BEGINNING OF THE
PERIOD...THEN TREND TO NEAR OR BELOW NORMAL BY THE MIDDLE OF NEXT
WEEK.
&&
.AVIATION...
12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
VFR CONDITIONS ARE PREDICTED AT ALL TERMINALS THROUGH TODAY.
TOWARD EVENING A FEW SHOWERS/STORMS WILL BE POSSIBLE...ESPECIALLY
AROUND KPIR OR EVEN KMBG. HOWEVER KATY/KABR SHOULD REMAIN DRY.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...TMT
SHORT TERM...PARKIN
LONG TERM...TDK
AVIATION...TDK
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
951 AM EDT FRI AUG 1 2014
.DISCUSSION...
RAIN HAS STAYED MAINLY EAST OF OUR AREA THIS MORNING...WITH JUST
SOME LIGHT SHOWERS IN OUR EXTREME EASTERN COUNTIES. ACTIVITY IN
THIS AREA WILL CONTINUE TO DECREASE THROUGH THE DAY AS THE LOW
MOVES AWAY. THE RAP AND HRRR SHOW SOME REDEVELOPMENT THIS
AFTERNOON WITH DAYTIME HEATING...MAINLY SOUTH AND IN HIGHER
TERRAIN...BUT COVERAGE SHOULD BE ISOLATED TO SCATTERED AT BEST.
WILL MAKE SOME SLIGHT POP ADJUSTMENTS FOR THE UPDATE...AS WELL AS
LOWERING CLOUD COVER. WITH LESS CLOUD COVER...TEMPS WILL NEED TO
BE BUMPED UP SLIGHTLY AS WELL IN NORTHERN AREAS.
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1200 AM CDT FRI AUG 1 2014
.DISCUSSION...
SEE AVIATION FOR 6Z TAF ISSUANCE.
&&
.AVIATION...
HEAVY RAINFALL HAS NOW MOVED OVER KIAH WITH OTHER SHOWERS AND
THUNDERSTORMS FROM THIS EVENING DISSIPATED OR WEAKENING. HIGH RES
MODELS CONTINUE TO SHOW REDEVELOPMENT EARLY THIS MORNING AS THE
FRONT MAKES A SECOND ATTEMPT TO PUSH SOUTHWARDS. LOOKS THAT FRONT
HAS STARTED ITS PUSH AS DEWPOINT AT KCLL HAS STARTED TO FALL AND
WINDS ARE NOW OUT OF THE NORTH. HIGH RES RAP AND HRRR REDEVELOP
PRECIP FROM KCXO SOUTHWARDS AND BRING AN END TO THE PRECIP FOR THE
INLAND SITES BY 10AM. NEAR THE COAST THE CHANCES OF PRECIP WILL
CONTINUE THROUGHOUT THE DAY AS HIGH MOISTURE/ SURFACE BOUNDARY
REMAIN OVER THE AREA. STILL LEFT MENTION FOR A POSSIBLE SHOWER AS
FAR INLAND AS KIAH THANKS TO NAM KEEPING PWAT VALUES AT 1.90".
FOR OUR NORTHERN TAF SITES OF KCLL AND KUTS REDEVELOPMENT DOES NOT
LOOK LIKELY AS THE FRONT IS NEAR OR ALREADY THROUGH THE AREA.
KUTS IT WILL BE CLOSE THIS MORNING AS WINDS HAVE NOT YET SHIFTED.
23
&&
.PREV DISCUSSION... /ISSUED 1049 PM CDT THU JUL 31 2014/
UPDATE...
BEEN A BUSY NIGHT WITH LOTS OF RAIN AND ONE DAMAGE REPORT. RADAR
ESTIMATES IN THE POLK/SAN JACINTO/LIBERTY SHOW WIDESPREAD RAINFALL
TOTALS OF 2 INCHES WITH ISOLATED AMOUNTS OF 4 TO 6.5 INCHES.
COLD FRONT HAS STALLED AROUND A HEARNE TO TYLER LINE WITH THE
STORMS HAVING MOVED OFF THE BOUNDARY REINFORCING THE COLD POOL
WITH THE OUTFLOW FROM THE FRONTAL BOUNDARY STORMS COLLIDING WITH
THE SEABREEZE AND FOCUS THE RAINS ACROSS THE NORTH. THE STORMS
HAVE CONTINUED TO PUSH VERY SLOWLY SOUTH AND 2 INCH PW AT GLS
STREAMING INTO THE CLUSTER IN EAST HARRIS-LIBERTY COUNTY. HAVE
CONCERNS THAT REDEVELOPMENT IS GOING TO OCCUR AFTER MIDNIGHT ALONG
THE FRONT AS IT GETS A NUDGE LATER TONIGHT AND PUSHED THE FRONT
DOWN TOWARD THE COAST BY 15-18Z FRIDAY.
HAVE ADJUSTED POPS BASED THE HRRR/RUC OF LATE WHICH HAVE DONE A
GOOD JOB AND SHOW THIS REDEVELOPMENT SCENARIO...GENERALLY RAISED
IN THE CENTRAL AND EAST...AND CONTINUED THE HEAVY RAIN THREAT.
TEMPERATURES LOOK ON TRACK TO COOL INTO THE LOWER 70S NORTH IN THE
WAKE OF THE FRONT.
45/23
PREV DISCUSSION... /ISSUED 652 PM CDT THU JUL 31 2014/
DISCUSSION...
SEE AVIATION FOR 0Z TAF ISSUANCE.
AVIATION...
SHOWERS AND THUNDERSTORMS ARE NOW INTO COLLEGE STATION AND
FORECASTED TO CONTINUE TO PUSH TO THE SOUTHEAST THIS EVENING. HIGH
RES MODELS HAVE STRUGGLED INITIALIZING AS ALL BUT THE RAP MISSED
THIS AFTERNOONS PRECIP NEAR KSGR/ KLBX. BECAUSE OF THE ABOVE HAVE
LEANED TOWARDS RAP WITH EVOLUTION OF SHOWERS AND THUNDERSTORMS.
MOST LIKELY THIS LINE WILL MOVE INTO KIAH AND KHOU IN THE NEXT TWO
HOURS BEFORE STARTING TO WEAKEN. LOOKS LIKE MOST TAF SITES WILL
SEE THUNDER WITH KLBX AND KGLS STILL IN QUESTION ON WHETHER
CURRENT CONVECTION WILL MAKE IT OR NOT. GLOBAL MODELS THEN BEGIN
TO DIFFER ON HOW THE FRONT WILL PROGRESS TOMORROW MORNING. THE GFS
PLUNGES THE DRIER AIR FARTHER TO THE SOUTH WHILE THE NAM HOLDS THE
DRIER AIR UP JUST AROUND KIAH TOMORROW. IF THE NAM IS RIGHT RAIN
COULD LINGER AROUND NEAR AND SOUTH OF KIAH TOMORROW. IF THE GFS
IS RIGHT THE PRECIP WILL BE CONFINED MORE NEAR THE COAST. FUTURE
TAF PACKAGES WILL WORK TO NARROW DOWN WHEN AND WHERE THE FRONT
WILL STALL. EITHER WAY BEHIND THE FONT PRECIP LOOKS TO COME TO AN
END. 23
PREV DISCUSSION... /ISSUED 627 PM CDT THU JUL 31 2014/
UPDATE...
HEAVY RAIN THREAT LOOKS TO BE RAPIDLY TAKING SHAPE OVER THE
NORTHERN 1/3 OF THE AREA. AREAS FROM CALDWELL TO COLLEGE STATION
TO MADISONVILLE HAVE ONGOING THUNDERSTORM THAT MOVED OFF THE
FRONTAL BOUNDARY AND GENERALLY MOVING AT 15-20 KNOTS TO THE SE.
SEABREEZE AND OUTFLOW BOUNDARY FROM STORMS IN THE METRO MARCHING
INLAND AND THE COLLISION AREA LOOKS TO FAVOR SOMETHING 20 MILES EITHER
SIDE OF A LINE FROM BRENHAM TO NAVASOTA TO CUT AND SHOOT TO
LIVINGSTON. HAVE DONE A QUICK UPDATE TO ADD LOCALLY HEAVY RAINFALL
AND RAISED POPS FOR THIS CORRIDOR. PW 2+ INCHES POOLED IN THERE
AND A BOUNDARY COLLISION LOOK TO FAVOR AT LEAST A FEW HOURS OF
HEAVY RAIN. STORM MOTIONS SHOULD SLOW AND SOME BACKBUILDING MAY
OCCUR...LATEST SPENES HIGHLIGHTING THIS THREAT AS WELL.
45/23
PREV DISCUSSION... /ISSUED 325 PM CDT THU JUL 31 2014/
DISCUSSION...
A NORTHWESTERLY FLOW ALOFT WILL HELP PUSH A COLD FRONT INTO SE TX
TONIGHT AND FRIDAY MORNING...AND THEN OFF THE COAST LATE FRIDAY.
LEANED HEAVILY ON THE 12Z NAM12 ALTHOUGH A MODEL CONSENSUS AGREED
WITH THE NAM OUTPUT. THE MAIN FORECAST CHALLENGE FOR TONIGHT
THROUGH FRIDAY IS THUNDERSTORM COVERAGE.
WEAK SHORTWAVE TROUGHS MOVING THROUGH THE FLOW ALOFT MAY HELP
GENERATE THUNDERSTORMS AHEAD OF THE COLD FRONT. THE SEABREEZE HAS
HELPED GENERATE THUNDERSTORMS TO THE SOUTHWEST OF METRO HOUSTON.
EXPECT THESE WILL BE FAIRLY SCATTERED THIS EVENING. OVERNIGHT
SHOULD SEE MORE WIDESPREAD COVERAGE AHEAD OF THE FRONT AS IT SINKS
INTO THE FORECAST AREA. THERE MAY BE A BREAK IN THE COVERAGE LATER
FRIDAY MORNING BEFORE REDEVELOPMENT FRIDAY AFTERNOON. THE FRONT
SHOULD WORK ITS WAY ALONG THE COAST BY FRIDAY NIGHT. THAT SAID...
THE MODELS HAVE BACKED OFF OF THE RAINFALL POTENTIAL...ESPECIALLY
ON FRIDAY. MODEL SOUNDINGS HAVE THE BEST PW/S OF ABOUT 2 INCHES
TONIGHT AND EARLY FRIDAY. THE NAMBUFR FORECAST SOUNDINGS SHOW THAT
THE BEST CHANCES FOR ISOLATED STRONG STORMS WILL BE LATE THIS
AFTERNOON AND EARLY EVENING.
THE FRONT WILL MOVE BACK INLAND AND THE SUBTROPICAL RIDGE WILL TRY
AND BUILD BACK OVER THE AREA NEXT WEEK. THIS WILL LEAD TO A WARMER
AND MORE HUMID TREND DURING THE FIRST HALF OF THE WEEK.
40
MARINE...
LIGHT TO OCCASIONALLY MODERATE ONSHORE WINDS WILL CONTINUE THROUGH
TONIGHT. A WEAK COLD FRONT WILL APPROACH THE COAST ON FRIDAY...
PROBABLY STALL AND MEANDER BACK AND FORTH NEAR THE COASTLINE
THROUGH THE WEEKEND. THIS BOUNDARY SHOULD SERVE AS A FOCUS FOR
PERIODS OF SHOWERS AND THUNDERSTORMS. LIGHT AND VARIABLE WINDS
SHOULD PERSIST WITH LOW SEAS... EXCEPT IN AND NEAR STORMS. AN
ONSHORE FLOW IS EXPECTED TO RETURN TO THE AREA WITH WINDS AND SEAS
REMAINING BELOW CAUTION LEVELS. 47
PREV DISCUSSION... /ISSUED 1209 PM CDT THU JUL 31 2014/
AVIATION...
NOT TOO MANY CHANGES TO ONGOING TAF PACKAGE...MAINLY TO PUSH BACK
TEMPOS A FEW HOURS. FRONTAL BOUNDARY MAKING SLOW PROGRESS TOWARD
SE TX. SAT IMAGERY DOES SHOW SOME BREAKS IN CLOUDS AHEAD OF IT
WHICH SHOULD ALLOW SOME DESTABILIZATION IN ADVANCE. GOES PW
ESTIMATES 2-2.3" PW`S ACROSS THE AREA. DO ANTICIPATE INCREASED SCT
ACTIVITY TO DEVELOP ACROSS N HALF OF SE TX THIS AFTN...THEN
SAGGING SWD TOWARD 1-10 & METRO AREAS DURING THE EVENING AND
NIGHTTIME HOURS. SEVERAL MODELS SHOWING FURTHER
ENHANCEMENT/REDEVELOPMENT BETWEEN 1-7AM CDT SOUTH OF A COLUMBUS-
LIVINGSTON LINE SO KEPT VCTS`S GOING OVERNIGHT AT LEAST UNTIL
TRENDS & INCREASED CONFIDENCE CAN BE ESTABLISHED. CONSIDERING
DEEPER AVAILABLE MOISTURE...RAINFALL COULD BE LOCALLY HEAVY AT
TIMES. PROBABLY SEE A BREAK AFTER SUNRISE...FOLLOWED BY POSSIBLE
MORE SCT ACTIVITY DURING THE AFTN DEPENDING WHERE THE BOUNDARY
BECOMES SITUATED AND IF WE CAN GET SOME INSTABILITY.
OTHERWISE...VFR OUTSIDE OF CONVECTION. 47
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 90 73 89 71 90 / 50 30 20 10 20
HOUSTON (IAH) 91 75 90 73 90 / 40 60 40 30 20
GALVESTON (GLS) 88 80 87 79 89 / 20 40 30 30 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
AVIATION/MARINE...23
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
150 PM EDT FRI AUG 1 2014
.SYNOPSIS...
AN UPPER TROUGH OF LOW PRESSURE WILL CONTINUE TO RETROGRADE WEST
TO THE MISSISSIPPI RIVER VALLEY...AND THE CENTER OF SURFACE HIGH
PRESSURE WILL SHIFT TO OUR EAST TODAY. AN UPPER DISTURBANCE
TRACKING JUST SOUTHEAST OF THE AREA WILL BRING MORE IN THE WAY OF
WIDESPREAD RAINFALL INTO THIS AFTERNOON. LINGERING MOISTURE IN
THE WAKE OF THIS FEATURE WILL COMBINE WITH HEATING TO RESULT IN
MORE SHOWERS AND STORMS OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1050 AM EDT FRIDAY...
TWO SHORT WAVES MOVING INTO GEORGIA AND WET VIRGINIA WILL CONTINUE
TO PROVIDE LIFT ACROSS THE FORECAST AREA THIS AFTERNOON. MAXIMUM RAINFALL
AMOUNT ALONG THE FOOTHILLS FROM HENRY COUNTY THROUGH WILKES COUNTY
WITH 1.5 TO 2.0 INCHES OF RAIN. FOR THE REST OF THE REGION MAINLY
EAST OF A LINE FROM HOT SPRINGS TO BOONE...AMOUNTS HAVE BEEN
GENERALLY FROM ONE THIRD TO THREE QUARTERS OF AN INCH.
UNUSUAL WIDESPREAD RAIN EVENT FOR MID SUMMER LOOKS IN STORE FOR
MUCH OF TODAY AS SHORTWAVE ENERGY CURRENTLY OVER SOUTHERN S
CAROLINA TRACKS NE CROSSING THE EASTERN PORTIONS OF THE CWA BY
THIS EVENING. THIS WILL CONTINUE TO ENHANCE THE OVERRUNNING OF
WARM/MOIST AIR ON SE FLOW OVERTOP A DEVELOPING COOL WEDGE EARLY
THIS MORNING...WITH SOME DEGREE OF PRECIP SPREADING NORTH AND WEST
ACROSS MUCH OF THE REGION BY 12Z.
STILL APPEARS THAT THE HEAVIEST RAINFALL WILL BE ACROSS SOUTHERN
SECTIONS AND ENHANCED ALONG THE SOUTHERN BLUE RIDGE BY UPSLOPE
FLOW OF NEAR 2 INCH PWATS INTO THIS AFTERNOON. HOWEVER APPEARS
CONVECTION ALONG THE COASTAL CAROLINAS CONTINUES TO DISRUPT THE
DEEPER SE TRAJECTORY WITH MORE CONVECTIVE NATURE COVERAGE FARTHER
TO THE SOUTH IN CONJUNCTION WITH THE HIGHER THETA-E AIR BEING
ADVECTED ACROSS THE FRONT INTO THE N CAROLINA COASTAL PLAINS. THIS
MAY HAVE ALSO CAUSED THE MODEL INIT TO BE TOO FAR WEST WITH THE
CORE OF HEAVIER RAINFALL BUT EXPECT THE CURRENT AXIS TO PIVOT MORE
NORTH-SOUTH ORIENTED SIMILAR TO THE LATEST HRRR AS THE WAVE HELPS
SHARPEN THE TROF WHILE BACKING THE FLOW ALOFT THIS MORNING.
QUESTION IS WHETHER OR NOT WILL GET ENOUGH HEAVIER RAINFALL OVER A
PROLONGED PERIOD TO PRODUCE FLOOD ISSUES GIVEN DRY CONDITIONS PER
LATEST FFG SHOWING 6 HOUR AMOUNTS OF 3.5-4.5 INCHES TO CAUSE
FLOODING. SINCE EXPECTING MOST OF THE RAINFALL TO REMAIN MORE
STRATIFORM WITH EMBEDDED HEAVIER DOWNPOURS WONT POST A WATCH OVER
THE SW FOR NOW BUT EXPECT UPSLOPE MAY CAUSE A GOOD 2-3+ INCHES
ALONG THE EASTERN SLOPES.
BEST LIFT SPREADS NE WITH THE WAVE THIS AFTERNOON CAUSING THE SOLID
AXIS OF PRECIP TO SHIFT ACROSS EASTERN/NE SECTIONS DURING THE
AFTERNOON WITH SOME TAPERING TO LIGHTER SHRA WEST/SW. COULD EVEN
SEE A FEW BREAKS DEVELOP FAR WEST ON THE PERIMETER OF THE COOL AIR
OTRW CLOUDY AND VERY COOL TO START AUGUST. HIGHS QUITE TRICKY AS
SOME SPOTS MAY SEE MORE OF A WINTER CAD EVENT WITH TEMPS ONLY
RISING A FEW DEGREES AT MOST ALONG THE BLUE RIDGE WHERE KEEPING IT
IN THE 60S FOR THE MOST PART. THINK SPOTS OVER THE PIEDMONT
INCLUDING SW VA INTO SE WVA MAY BE ABLE TO BUMP VALUES INTO THE
LOW/MID 70S ESPCLY IF THE RAINFALL DIMINISHES A BIT FASTER AND
THINGS BRIGHTEN SLIGHTLY.
IMPULSE EXITS THIS EVENING LEAVING THE REGION WITHIN THE RESIDUAL
WEDGE BUT UNDERNEATH A CONTINUED DIFFLUENT PATTERN ALOFT ON THE
FRONT OF THE 5H TROF. LITTLE UPPER SUPPORT REMAINING OVERNIGHT FOR
MUCH ADDED RAINFALL ESPCLY AFTER MIDNIGHT BUT LIKELY ENOUGH WEAK
UPSLOPE TO KEEP LIKELY OR HIGHER POPS GOING BLUE RIDGE INTO LATE
THIS EVENING. FLOW BEHIND THE DEPARTING WAVE MAY ACTUALLY TURN
WESTERLY ENOUGH TO SHUT OFF SHRA WESTERN HALF LATE SO CUT POPS
BACK TO MAINLY CHANCE AFTER MIDNIGHT WHEN MAY BE MORE DRIZZLE/FOG
OUT EAST. CONTINUED COOL WITH LOWS LIKELY ONLY FALLING A FEW
DEGREES BUT AFTER A CHILLY DAY WONT TAKE MUCH TO GET INTO THE 50S
WEST AND LOW 60S EAST.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
AS OF 314 AM EDT FRIDAY...
A BERMUDA HIGH REMAINS OVER THE WESTERN ATLANTIC WHILE AN UPPER
LEVEL TROUGH IS DRAPED OVER THE MISSISSIPPI VALLEY THIS WEEKEND.
WITH THE FORECAST AREA IN BETWEEN THESE TWO SYNOPTIC
FEATURES...IMPULSES WITH TROPICAL MOISTURE WILL KEEP A GOOD CHANCE
FOR SHOWERS AND SCATTERED THUNDERSTORMS IN THE AREA OVER THE
WEEKEND. COMPARED TO YESTERDAY...MODELS HAVE SHIFTED THE AXIS OF
HEAVY STEADY RAIN EAST ALONG THE COAST. THE FORECAST AREA WILL STILL
SEE A FAIR AMOUNT OF RAIN OVER THE WEEKEND...BUT WILL BE MORE
CONFIDED TO THE AFTERNOON AND EVENING HOURS. DESPITE THE MODELS
TRENDING DRIER...KEEP POPS THROUGH THE ENTIRE PERIOD WITH LOW CHANCE
DURING NON-DIURNAL HEATING HOURS AND HIGH CHANCE-LIKELY DURING THE
AFTERNOON AND EVENING. ALSO WITH THE DRIER MODEL SOLUTIONS...EDGE
TEMPERATURES UP A FEW DEGREES EACH AFTERNOON. DESPITE WARMING THE
FORECAST TEMPERATURES...THEY WILL REMAIN COOLER THAN NORMAL BY AT
LEAST 10F FOR THE FIRST WEEKEND IN AUGUST.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 1230 PM EDT FRIDAY...
AT THE SURFACE TUESDAY...HIGH PRESSURE SITS OVER WEST VIRGINIA WHILE
A SLOW MOVING COLD FRONT IS ACROSS THE OHIO VALLEY. TS BERTHA OR
WHAT IS REMAINING OF IT IS FORECAST TO REMAIN WELL OFF SHORE AND
WILL NOT BE A FACTOR IN OUR REGION NEXT WEEK. AN UPPER LEVEL TROUGH
REMAINS SITUATED ACROSS THE EASTERN US. THE UPPER LEVEL FLOW WILL
BECOME MORE ZONAL BY THE END OF THE PERIOD. THE FRONT ACROSS THE
OHIO VALLEY WILL SLOWLY DRIFT AND PARTIALLY STALL OUT ACROSS
NORTHERN PORTIONS OF OUR CWA BY THURSDAY INTO FRIDAY. WHILE PWATS
ARE NOT IMPRESSIVE...GENERALLY 0.75-1.25 INCHES DEPENDING ON THE
LOCATION...EXPECT ISOLATED TO SCATTERED THUNDERSTORMS EACH AFTERNOON
BEGINNING DURING PEAK HEATING AND TAPERING OFF AROUND SUNSET. FOCUS
OF THE LOW CHANCE POPS ARE ACROSS THE MOUNTAINS AND GENERALLY NORTH
OF ROUTE 460.
SURFACE TEMPS WILL BE RIGHT AROUND NORMAL FOR THE PERIOD. 850MB
TEMPS OF +15-17C WILL CORRESPOND TO SURFACE HIGHS OF MID TO UPPER
80S EAST OF THE BLUE RIDGE AND LOWER 80S ACROSS THE MOUNTAINS.
DEWPTS IN THE UPPER 50S TO LOWER 60S WILL KEEP NIGHT TIME TEMPS UP A
BIT.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 145 PM EDT FRIDAY...
COMBINATION OF UPSLOPE LOW LEVEL FLOW AND LOFT FROM TWO SHORT
WAVES CROSSING THE AREA...POOR FLYING CONDITIONS WILL CONTINUE
ACROSS MUCH OF THE REGION TONIGHT. THE BEST COVERAGE OF RAIN WILL
BE ALONG AND EAST OF THE BLUE RIDGE BEFORE 06Z/2AM TONIGHT.
AFTER SUNSET...CEILINGS WILL DROP AND REMAIN AT IFR TO LIFR
LEVELS WITH AREAS OF FOG AND DRIZZLE. BOTH THE NAM AND GFS SHOWED
THE MAJORITY OF THE HEAVIER PRECIPITATION MOVING NORTHEAST AND OUT
OF SOUTHWEST VIRGINIA BY 09Z/5AM.
LOWER CONFIDENCE ON HOW FAST WEDGE WILL ERODE ON SATURDAY. BUFKIT
FORECAST SOUNDINGS SUGGEST SURFACE AND LOW LEVEL WINDS WILL COME
AROUND TO THE SOUTHWEST AFTER 15Z/11AM. EXPECT KLYH WILL BE THE
LAST AIRPORT TO LIFT OUT OF IFR CONDITIONS.
EXTENDED AVIATION DISCUSSION...
THE BROAD UPPER TROUGH OF LOW PRESSURE WILL LINGER ACROSS THE
EASTERN UNITED STATES THROUGH SUNDAY CONTINUING TO RETROGRADE
FROM THE EASTERN/CENTRAL GREAT LAKES TO THE WESTERN GREAT LAKES BY
THE WEEKEND. SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ARE
EXPECTED AGAIN ON SUNDAY.
FOR MONDAY AND TUESDAY...THE AIR MASS WILL SLOWLY BECOME WARMER
AND MORE UNSTABLE. ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS ARE EXPECTED IN THE AFTERNOON AND
EVENING...ESPECIALLY TUESDAY...WITH BRIEF PERIODS OF MVFR- IFR
CIGS/VSBYS EXPECTED IN SHRA/TSRA.
A WEAK COLD FRONT MOVES SLOWLY SOUTH FROM THE OHIO VALLEY ACROSS
THE MID ATLANTIC REGION...THIS WILL ALSO BRING A CHANCE OF SHOWERS
AND THUNDERSTORMS.
&&
.HYDROLOGY...
AS OF 330 AM EDT FRIDAY...
RAINFALL TOTALS OF 1-3 INCHES IS EXPECTED ALONG THE ENHANCED
UPSLOPE REGIONS OF THE BLUE RIDGE AND FOOTHILLS MAINLY SOUTH OF
ROANOKE WITH A GOOD 1-2 INCHES ELSW OVER THE PIEDMONT SECTIONS OF
NORTHWEST NORTH CAROLINA INTO SOUTHSIDE VIRGINIA BY THIS
AFTERNOON.
GIVEN THE VERY DRY ANTECEDENT CONDITIONS OF LATE AND THE OVERALL
LACK OF HEAVIER RAINFALL RATES...WIDESPREAD FLOODING OR FLASH
FLOODING IS NOT EXPECTED BUT LOCALIZED SMALL STREAM AND POOR
DRAINAGE FLOODING COULD OCCUR ESPCLY WHERE HEAVIER DOWNPOURS ARE
REALIZED. RAINFALL TOTALS WILL QUICKLY TAPER OFF HEADING INTO FAR
WESTERN VIRGINIA AND SE WEST VIRGINIA WHERE ONLY UP TO A HALF INCH
LOOKS POSSIBLE WITH AN INCH OR MORE LIKELY IN AREAS AROUND
LYNCHBURG.
&&
.EQUIPMENT...
AS OF 100 PM EDT FRIDAY...
THE NOAA WEATHER RADIO AT WYTHEVILLE VA...WZ2500...BROADCASTING
ON A FREQUENCY OF 162.450 MHZ...IS BACK ON THE AIR.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/NF
NEAR TERM...AMS/JH
SHORT TERM...RCS
LONG TERM...CF
AVIATION...JH/AMS
HYDROLOGY...JH
EQUIPMENT...AMS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1052 AM EDT FRI AUG 1 2014
.SYNOPSIS...
AN UPPER TROUGH OF LOW PRESSURE WILL CONTINUE TO RETROGRADE WEST
TO THE MISSISSIPPI RIVER VALLEY...AND THE CENTER OF SURFACE HIGH
PRESSURE WILL SHIFT TO OUR EAST TODAY. AN UPPER DISTURBANCE
TRACKING JUST SOUTHEAST OF THE AREA WILL BRING MORE IN THE WAY OF
WIDESPREAD RAINFALL INTO THIS AFTERNOON. LINGERING MOISTURE IN
THE WAKE OF THIS FEATURE WILL COMBINE WITH HEATING TO RESULT IN
MORE SHOWERS AND STORMS OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1050 AM EDT FRIDAY...
TWO SHORT WAVES MOVING INTO GEORGIA AND WET VIRGINIA WILL CONTINUE
TO PROVIDE LIFT ACROSS THE FORECAST AREA THIS AFTERNOON. MAXIMUM RAINFALL
AMOUNT ALONG THE FOOTHILLS FROM HENRY COUNTY THROUGH WILKES COUNTY
WITH 1.5 TO 2.0 INCHES OF RAIN. FOR THE REST OF THE REGION MAINLY
EAST OF A LINE FROM HOT SPRINGS TO BOONE...AMOUNTS HAVE BEEN
GENERALLY FROM ONE THIRD TO THREE QUARTERS OF AN INCH.
UNUSUAL WIDESPREAD RAIN EVENT FOR MID SUMMER LOOKS IN STORE FOR
MUCH OF TODAY AS SHORTWAVE ENERGY CURRENTLY OVER SOUTHERN S
CAROLINA TRACKS NE CROSSING THE EASTERN PORTIONS OF THE CWA BY
THIS EVENING. THIS WILL CONTINUE TO ENHANCE THE OVERRUNNING OF
WARM/MOIST AIR ON SE FLOW OVERTOP A DEVELOPING COOL WEDGE EARLY
THIS MORNING...WITH SOME DEGREE OF PRECIP SPREADING NORTH AND WEST
ACROSS MUCH OF THE REGION BY 12Z.
STILL APPEARS THAT THE HEAVIEST RAINFALL WILL BE ACROSS SOUTHERN
SECTIONS AND ENHANCED ALONG THE SOUTHERN BLUE RIDGE BY UPSLOPE
FLOW OF NEAR 2 INCH PWATS INTO THIS AFTERNOON. HOWEVER APPEARS
CONVECTION ALONG THE COASTAL CAROLINAS CONTINUES TO DISRUPT THE
DEEPER SE TRAJECTORY WITH MORE CONVECTIVE NATURE COVERAGE FARTHER
TO THE SOUTH IN CONJUNCTION WITH THE HIGHER THETA-E AIR BEING
ADVECTED ACROSS THE FRONT INTO THE N CAROLINA COASTAL PLAINS. THIS
MAY HAVE ALSO CAUSED THE MODEL INIT TO BE TOO FAR WEST WITH THE
CORE OF HEAVIER RAINFALL BUT EXPECT THE CURRENT AXIS TO PIVOT MORE
NORTH-SOUTH ORIENTED SIMILAR TO THE LATEST HRRR AS THE WAVE HELPS
SHARPEN THE TROF WHILE BACKING THE FLOW ALOFT THIS MORNING.
QUESTION IS WHETHER OR NOT WILL GET ENOUGH HEAVIER RAINFALL OVER A
PROLONGED PERIOD TO PRODUCE FLOOD ISSUES GIVEN DRY CONDITIONS PER
LATEST FFG SHOWING 6 HOUR AMOUNTS OF 3.5-4.5 INCHES TO CAUSE
FLOODING. SINCE EXPECTING MOST OF THE RAINFALL TO REMAIN MORE
STRATIFORM WITH EMBEDDED HEAVIER DOWNPOURS WONT POST A WATCH OVER
THE SW FOR NOW BUT EXPECT UPSLOPE MAY CAUSE A GOOD 2-3+ INCHES
ALONG THE EASTERN SLOPES.
BEST LIFT SPREADS NE WITH THE WAVE THIS AFTERNOON CAUSING THE SOLID
AXIS OF PRECIP TO SHIFT ACROSS EASTERN/NE SECTIONS DURING THE
AFTERNOON WITH SOME TAPERING TO LIGHTER SHRA WEST/SW. COULD EVEN
SEE A FEW BREAKS DEVELOP FAR WEST ON THE PERIMETER OF THE COOL AIR
OTRW CLOUDY AND VERY COOL TO START AUGUST. HIGHS QUITE TRICKY AS
SOME SPOTS MAY SEE MORE OF A WINTER CAD EVENT WITH TEMPS ONLY
RISING A FEW DEGREES AT MOST ALONG THE BLUE RIDGE WHERE KEEPING IT
IN THE 60S FOR THE MOST PART. THINK SPOTS OVER THE PIEDMONT
INCLUDING SW VA INTO SE WVA MAY BE ABLE TO BUMP VALUES INTO THE
LOW/MID 70S ESPCLY IF THE RAINFALL DIMINISHES A BIT FASTER AND
THINGS BRIGHTEN SLIGHTLY.
IMPULSE EXITS THIS EVENING LEAVING THE REGION WITHIN THE RESIDUAL
WEDGE BUT UNDERNEATH A CONTINUED DIFFLUENT PATTERN ALOFT ON THE
FRONT OF THE 5H TROF. LITTLE UPPER SUPPORT REMAINING OVERNIGHT FOR
MUCH ADDED RAINFALL ESPCLY AFTER MIDNIGHT BUT LIKELY ENOUGH WEAK
UPSLOPE TO KEEP LIKELY OR HIGHER POPS GOING BLUE RIDGE INTO LATE
THIS EVENING. FLOW BEHIND THE DEPARTING WAVE MAY ACTUALLY TURN
WESTERLY ENOUGH TO SHUT OFF SHRA WESTERN HALF LATE SO CUT POPS
BACK TO MAINLY CHANCE AFTER MIDNIGHT WHEN MAY BE MORE DRIZZLE/FOG
OUT EAST. CONTINUED COOL WITH LOWS LIKELY ONLY FALLING A FEW
DEGREES BUT AFTER A CHILLY DAY WONT TAKE MUCH TO GET INTO THE 50S
WEST AND LOW 60S EAST.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
AS OF 314 AM EDT FRIDAY...
A BERMUDA HIGH REMAINS OVER THE WESTERN ATLANTIC WHILE AN UPPER
LEVEL TROUGH IS DRAPED OVER THE MISSISSIPPI VALLEY THIS WEEKEND.
WITH THE FORECAST AREA IN BETWEEN THESE TWO SYNOPTIC
FEATURES...IMPULSES WITH TROPICAL MOISTURE WILL KEEP A GOOD CHANCE
FOR SHOWERS AND SCATTERED THUNDERSTORMS IN THE AREA OVER THE
WEEKEND. COMPARED TO YESTERDAY...MODELS HAVE SHIFTED THE AXIS OF
HEAVY STEADY RAIN EAST ALONG THE COAST. THE FORECAST AREA WILL STILL
SEE A FAIR AMOUNT OF RAIN OVER THE WEEKEND...BUT WILL BE MORE
CONFIDED TO THE AFTERNOON AND EVENING HOURS. DESPITE THE MODELS
TRENDING DRIER...KEEP POPS THROUGH THE ENTIRE PERIOD WITH LOW CHANCE
DURING NON-DIURNAL HEATING HOURS AND HIGH CHANCE-LIKELY DURING THE
AFTERNOON AND EVENING. ALSO WITH THE DRIER MODEL SOLUTIONS...EDGE
TEMPERATURES UP A FEW DEGREES EACH AFTERNOON. DESPITE WARMING THE
FORECAST TEMPERATURES...THEY WILL REMAIN COOLER THAN NORMAL BY AT
LEAST 10F FOR THE FIRST WEEKEND IN AUGUST.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 330 PM EDT THURSDAY...
MONDAY THROUGH WEDNESDAY THE TROFFING IN THE EAST FLATTENS. A
SURFACE COLD FRONT COMES SOUTH THROUGH NEW ENGLAND MONDAY
TUESDAY...BUT WILL ONLY MOVE SO FAR SOUTH WITH THE BOUNDARY PARALLEL
TO THE UPPER FLOW.
THIS WILL KEEP THE FORECAST AREA ON THE WARM UNSTABLE AIR MASS ON
THE SOUTH SIDE OF THE FRONT THROUGH THURSDAY. DEEPEST MOISTURE AND
BEST LIFT WILL BE FOCUSED ALONG THE COAST FRONT ACROSS THE CAROLINAS
AND GEORGIA. NOT SEEING ANY ORGANIZED FORCING FOR THE COUNTY WARNING
AREA.
TEMPERATURES WILL BE NEAR NORMAL THROUGH THE PERIOD.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
AS OF 650 AM EDT FRIDAY...
FLYING CONDITIONS WILL CONTINUE TO DETERIORATE THIS MORNING AS AN
AXIS OF SHOWERS WITH EMBEDDED HEAVY RAIN SLIDES SLOWLY
NORTH...LIKELY COVERING MOST OF THE REGION BY MID MORNING. MODELS
CONTINUE TO SHOW THIS SCENARIO WITH WIDESPREAD RAINFALL ESPCLY
BLUE RIDGE EAST INTO THIS AFTERNOON BUT DIFFER ON EXACTLY WHERE
THE HEAVIEST MAY TAKE SHAPE. STILL APPEARS SOUTHERN SECTIONS
RUNNING UP ALONG THE EASTERN SLOPES OF THE SOUTHERN BLUE RIDGE
WILL SEE THE HEAVIEST RAINFALL INCLUDING WIDESPREAD MVFR TO IFR
FOR MUCH OF TODAY...AND PERHAPS INTO THE OVERNIGHT. WESTERN
LOCATIONS SUCH AS KBLF/KLWB MAY BREAK BACK OUT INTO VFR AFTER
EARLY RAINFALL GIVEN DOWNSLOPE AND PASSAGE OF DEEPER MOISTURE TO
THE EAST SO WENT CLOSER TO THE LESS PESSIMISTIC GFS THERE. ELSW
STAYING CLOSER TO THE LOWER CIGS SUGGESTED BY THE NAM BY THIS
AFTERNOON GIVEN EASTERLY FLOW ONCE THINGS BECOME SATURATED THIS
MORNING. ALSO PERIODS OF MVFR VSBYS LIKELY ESPCLY FROM THE
MOUNTAINS EAST INTO THE AFTERNOON...WITH POSSIBLE IFR AT TIMES IN
HEAVIER RAIN/FOG NEAR THE BLUE RIDGE...INCLUDING LOCATIONS SUCH
AS KBCB/KROA.
DESPITE THE EXODUS OF THE WAVE THIS EVENING...LINGERING WEDGE AND
DIFFLUENCE ALOFT LIKELY TO KEEP AT LEAST SOME SPOTTY RAIN/DRIZZLE
AROUND WHICH MAY HOLD MVFR TO IFR CIGS ALONG WITH FOG IN PLACE
UNTIL EARLY SATURDAY MORNING. OTRW WILL HAVE WIDESPREAD IFR CONDITIONS
FROM THE BLUE RIDGE EAST OVERNIGHT WITH MVFR AT KBLF AND LIFR LATE
AT KLWB DUE TO DENSE FOG.
EXTENDED AVIATION DISCUSSION...
THE BROAD UPPER TROUGH OF LOW PRESSURE WILL LINGER ACROSS THE
EASTERN UNITED STATES THROUGH SUNDAY CONTINUING TO RETROGRADE
FROM THE EASTERN/CENTRAL GREAT LAKES TO THE WESTERN GREAT LAKES BY
THE WEEKEND.
FOR SATURDAY AND SUNDAY...THE AIR MASS WILL SLOWLY BECOME WARMER
AND MORE UNSTABLE. SCT SHRA/TSRA EXPECTED AGAIN SATURDAY WITH
ONLY LIMITED INSTABILITY EVIDENT. FOR SUNDAY...BETTER CHANCE OF
TSRA WITH BETTER INSTABILITY ACROSS MUCH OF THE CWA...SW FLOW
ALOFT...AND INCREASING MOISTURE LEVELS. THUS...BRIEF PERIODS OF
MVFR-IFR CIGS/VSBYS EXPECTED IN SHRA/TSRA SATURDAY AND MORE
LIKELY SUNDAY AFTERNOON. SOME DRYING WITH A RETURN TO OVERALL VFR
POSSIBLE MONDAY INTO TUESDAY AS ANOTHER WEAK COOL FRONT SWEEPS IN
FROM THE NW AND TAKES MOST MOISTURE TO THE SE OF THE REGION.
&&
.HYDROLOGY...
AS OF 330 AM EDT FRIDAY...
STEADY LIGHT TO MODERATE RAINFALL WILL SPREAD SLOWLY NORTH THROUGH
THE MORNING WITH PERIODS OF HEAVY RAIN POSSIBLE FROM THE SOUTHERN
BLUE RIDGE...FOOTHILLS EAST ACROSS THE PIEDMONT. RAINFALL TOTALS OF
1-3 INCHES IS EXPECTED ALONG THE ENHANCED UPSLOPE REGIONS OF THE
BLUE RIDGE AND FOOTHILLS MAINLY SOUTH OF ROANOKE WITH A GOOD 1-2
INCHES ELSW OVER THE PIEDMONT SECTIONS OF NORTHWEST NORTH CAROLINA
INTO SOUTHSIDE VIRGINIA BY THIS AFTERNOON. GIVEN THE VERY DRY
ANTECEDENT CONDITIONS OF LATE AND THE OVERALL LACK OF HEAVIER
RAINFALL RATES...WIDESPREAD FLOODING OR FLASH FLOODING IS NOT
EXPECTED BUT LOCALIZED SMALL STREAM AND POOR DRAINAGE FLOODING
COULD OCCUR ESPCLY WHERE HEAVIER DOWNPOURS ARE REALIZED. RAINFALL
TOTALS SHOULD QUICKLY TAPER OFF HEADING INTO FAR WESTERN VIRGINIA
AND SE WEST VIRGINIA WHERE ONLY UP TO A HALF INCH LOOKS POSSIBLE
WITH AN INCH OR MORE LIKELY IN AREAS AROUND LYNCHBURG.
&&
.EQUIPMENT...
THE NOAA WEATHER RADIO AT WYTHEVILLE VA...WZ2500...BROADCASTING
ON A FREQUENCY OF 162.450 MHZ...IS OFF THE AIR. TECHNICIANS ARE
WAITING ON DELIVERY OF PARTS TO MAKE REPAIRS. THE EARLIEST THE
RADIO WILL BE WORKING AGAIN IS LATER TODAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/NF
NEAR TERM...AMS/JH
SHORT TERM...RCS
LONG TERM...AMS
AVIATION...JH/NF/WP
HYDROLOGY...JH
EQUIPMENT...DS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
724 AM EDT FRI AUG 1 2014
.SYNOPSIS...
AN UPPER TROUGH OF LOW PRESSURE WILL CONTINUE TO RETROGRADE WEST
TO THE MISSISSIPPI RIVER VALLEY...AND THE CENTER OF SURFACE HIGH
PRESSURE WILL SHIFT TO OUR EAST TODAY. AN UPPER DISTURBANCE
TRACKING JUST SOUTHEAST OF THE AREA WILL BRING MORE IN THE WAY OF
WIDESPREAD RAINFALL INTO THIS AFTERNOON. LINGERING MOISTURE IN
THE WAKE OF THIS FEATURE WILL COMBINE WITH HEATING TO RESULT IN
MORE SHOWERS AND STORMS OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 240 AM EDT FRIDAY...
UNUSUAL WIDESPREAD RAIN EVENT FOR MID SUMMER LOOKS IN STORE FOR
MUCH OF TODAY AS SHORTWAVE ENERGY CURRENTLY OVER SOUTHERN S
CAROLINA TRACKS NE CROSSING THE EASTERN PORTIONS OF THE CWA BY
THIS EVENING. THIS WILL CONTINUE TO ENHANCE THE OVERRUNNING OF
WARM/MOIST AIR ON SE FLOW OVERTOP A DEVELOPING COOL WEDGE EARLY
THIS MORNING...WITH SOME DEGREE OF PRECIP SPREADING NORTH AND WEST
ACROSS MUCH OF THE REGION BY 12Z. STILL APPEARS THAT THE HEAVIEST
RAINFALL WILL BE ACROSS SOUTHERN SECTIONS AND ENHANCED ALONG THE
SOUTHERN BLUE RIDGE BY UPSLOPE FLOW OF NEAR 2 INCH PWATS INTO THIS
AFTERNOON. HOWEVER APPEARS CONVECTION ALONG THE COASTAL CAROLINAS
CONTINUES TO DISRUPT THE DEEPER SE TRAJECTORY WITH MORE CONVECTIVE
NATURE COVERAGE FARTHER TO THE SOUTH IN CONJUNCTION WITH THE
HIGHER THETA-E AIR BEING ADVECTED ACROSS THE FRONT INTO THE
N CAROLINA COASTAL PLAINS. THIS MAY HAVE ALSO CAUSED THE MODEL
INIT TO BE TOO FAR WEST WITH THE CORE OF HEAVIER RAINFALL BUT
EXPECT THE CURRENT AXIS TO PIVOT MORE NORTH- SOUTH ORIENTED
SIMILAR TO THE LATEST HRRR AS THE WAVE HELPS SHARPEN THE TROF
WHILE BACKING THE FLOW ALOFT THIS MORNING. QUESTION IS WHETHER OR
NOT WILL GET ENOUGH HEAVIER RAINFALL OVER A PROLONGED PERIOD TO
PRODUCE FLOOD ISSUES GIVEN DRY CONDITIONS PER LATEST FFG SHOWING 6
HOUR AMOUNTS OF 3.5-4.5 INCHES TO CAUSE FLOODING. SINCE EXPECTING
MOST OF THE RAINFALL TO REMAIN MORE STRATIFORM WITH EMBEDDED
HEAVIER DOWNPOURS WONT POST A WATCH OVER THE SW FOR NOW BUT EXPECT
UPSLOPE MAY CAUSE A GOOD 2-3+ INCHES ALONG THE EASTERN SLOPES.
BEST LIFT SPREADS NE WITH THE WAVE THIS AFTERNOON CAUSING THE SOLID
AXIS OF PRECIP TO SHIFT ACROSS EASTERN/NE SECTIONS DURING THE
AFTERNOON WITH SOME TAPERING TO LIGHTER SHRA WEST/SW. COULD EVEN
SEE A FEW BREAKS DEVELOP FAR WEST ON THE PERIMETER OF THE COOL AIR
OTRW CLOUDY AND VERY COOL TO START AUGUST. HIGHS QUITE TRICKY AS
SOME SPOTS MAY SEE MORE OF A WINTER CAD EVENT WITH TEMPS ONLY
RISING A FEW DEGREES AT MOST ALONG THE BLUE RIDGE WHERE KEEPING IT
IN THE 60S FOR THE MOST PART. THINK SPOTS OVER THE PIEDMONT
INCLUDING SW VA INTO SE WVA MAY BE ABLE TO BUMP VALUES INTO THE
LOW/MID 70S ESPCLY IF THE RAINFALL DIMINISHES A BIT FASTER AND
THINGS BRIGHTEN SLIGHTLY.
IMPULSE EXITS THIS EVENING LEAVING THE REGION WITHIN THE RESIDUAL
WEDGE BUT UNDERNEATH A CONTINUED DIFFLUENT PATTERN ALOFT ON THE
FRONT OF THE 5H TROF. LITTLE UPPER SUPPORT REMAINING OVERNIGHT FOR
MUCH ADDED RAINFALL ESPCLY AFTER MIDNIGHT BUT LIKELY ENOUGH WEAK
UPSLOPE TO KEEP LIKELY OR HIGHER POPS GOING BLUE RIDGE INTO LATE
THIS EVENING. FLOW BEHIND THE DEPARTING WAVE MAY ACTUALLY TURN
WESTERLY ENOUGH TO SHUT OFF SHRA WESTERN HALF LATE SO CUT POPS
BACK TO MAINLY CHANCE AFTER MIDNIGHT WHEN MAY BE MORE DRIZZLE/FOG
OUT EAST. CONTINUED COOL WITH LOWS LIKELY ONLY FALLING A FEW
DEGREES BUT AFTER A CHILLY DAY WONT TAKE MUCH TO GET INTO THE 50S
WEST AND LOW 60S EAST.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
AS OF 314 AM EDT FRIDAY...
A BERMUDA HIGH REMAINS OVER THE WESTERN ATLANTIC WHILE AN UPPER
LEVEL TROUGH IS DRAPED OVER THE MISSISSIPPI VALLEY THIS WEEKEND.
WITH THE FORECAST AREA IN BETWEEN THESE TWO SYNOPTIC
FEATURES...IMPULSES WITH TROPICAL MOISTURE WILL KEEP A GOOD CHANCE
FOR SHOWERS AND SCATTERED THUNDERSTORMS IN THE AREA OVER THE
WEEKEND. COMPARED TO YESTERDAY...MODELS HAVE SHIFTED THE AXIS OF
HEAVY STEADY RAIN EAST ALONG THE COAST. THE FORECAST AREA WILL STILL
SEE A FAIR AMOUNT OF RAIN OVER THE WEEKEND...BUT WILL BE MORE
CONFIDED TO THE AFTERNOON AND EVENING HOURS. DESPITE THE MODELS
TRENDING DRIER...KEEP POPS THROUGH THE ENTIRE PERIOD WITH LOW CHANCE
DURING NON-DIURNAL HEATING HOURS AND HIGH CHANCE-LIKELY DURING THE
AFTERNOON AND EVENING. ALSO WITH THE DRIER MODEL SOLUTIONS...EDGE
TEMPERATURES UP A FEW DEGREES EACH AFTERNOON. DESPITE WARMING THE
FORECAST TEMPERATURES...THEY WILL REMAIN COOLER THAN NORMAL BY AT
LEAST 10F FOR THE FIRST WEEKEND IN AUGUST.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 330 PM EDT THURSDAY...
MONDAY THROUGH WEDNESDAY THE TROFFING IN THE EAST FLATTENS. A
SURFACE COLD FRONT COMES SOUTH THROUGH NEW ENGLAND MONDAY
TUESDAY...BUT WILL ONLY MOVE SO FAR SOUTH WITH THE BOUNDARY PARALLEL
TO THE UPPER FLOW.
THIS WILL KEEP THE FORECAST AREA ON THE WARM UNSTABLE AIR MASS ON
THE SOUTH SIDE OF THE FRONT THROUGH THURSDAY. DEEPEST MOISTURE AND
BEST LIFT WILL BE FOCUSED ALONG THE COAST FRONT ACROSS THE CAROLINAS
AND GEORGIA. NOT SEEING ANY ORGANIZED FORCING FOR THE COUNTY WARNING
AREA.
TEMPERATURES WILL BE NEAR NORMAL THROUGH THE PERIOD.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 650 AM EDT FRIDAY...
FLYING CONDITIONS WILL CONTINUE TO DETERIORATE THIS MORNING AS AN
AXIS OF SHOWERS WITH EMBEDDED HEAVY RAIN SLIDES SLOWLY
NORTH...LIKELY COVERING MOST OF THE REGION BY MID MORNING. MODELS
CONTINUE TO SHOW THIS SCENARIO WITH WIDESPREAD RAINFALL ESPCLY
BLUE RIDGE EAST INTO THIS AFTERNOON BUT DIFFER ON EXACTLY WHERE
THE HEAVIEST MAY TAKE SHAPE. STILL APPEARS SOUTHERN SECTIONS
RUNNING UP ALONG THE EASTERN SLOPES OF THE SOUTHERN BLUE RIDGE
WILL SEE THE HEAVIEST RAINFALL INCLUDING WIDESPREAD MVFR TO IFR
FOR MUCH OF TODAY...AND PERHAPS INTO THE OVERNIGHT. WESTERN
LOCATIONS SUCH AS KBLF/KLWB MAY BREAK BACK OUT INTO VFR AFTER
EARLY RAINFALL GIVEN DOWNSLOPE AND PASSAGE OF DEEPER MOISTURE TO
THE EAST SO WENT CLOSER TO THE LESS PESSIMISTIC GFS THERE. ELSW
STAYING CLOSER TO THE LOWER CIGS SUGGESTED BY THE NAM BY THIS
AFTERNOON GIVEN EASTERLY FLOW ONCE THINGS BECOME SATURATED THIS
MORNING. ALSO PERIODS OF MVFR VSBYS LIKELY ESPCLY FROM THE
MOUNTAINS EAST INTO THE AFTERNOON...WITH POSSIBLE IFR AT TIMES IN
HEAVIER RAIN/FOG NEAR THE BLUE RIDGE...INCLUDING LOCATIONS SUCH
AS KBCB/KROA.
DESPITE THE EXODUS OF THE WAVE THIS EVENING...LINGERING WEDGE AND
DIFFLUENCE ALOFT LIKELY TO KEEP AT LEAST SOME SPOTTY RAIN/DRIZZLE
AROUND WHICH MAY HOLD MVFR TO IFR CIGS ALONG WITH FOG IN PLACE
UNTIL EARLY SATURDAY MORNING. OTRW WILL HAVE WIDESPREAD IFR CONDITIONS
FROM THE BLUE RIDGE EAST OVERNIGHT WITH MVFR AT KBLF AND LIFR LATE
AT KLWB DUE TO DENSE FOG.
EXTENDED AVIATION DISCUSSION...
THE BROAD UPPER TROUGH OF LOW PRESSURE WILL LINGER ACROSS THE
EASTERN UNITED STATES THROUGH SUNDAY CONTINUING TO RETROGRADE
FROM THE EASTERN/CENTRAL GREAT LAKES TO THE WESTERN GREAT LAKES BY
THE WEEKEND.
FOR SATURDAY AND SUNDAY...THE AIR MASS WILL SLOWLY BECOME WARMER
AND MORE UNSTABLE. SCT SHRA/TSRA EXPECTED AGAIN SATURDAY WITH
ONLY LIMITED INSTABILITY EVIDENT. FOR SUNDAY...BETTER CHANCE OF
TSRA WITH BETTER INSTABILITY ACROSS MUCH OF THE CWA...SW FLOW
ALOFT...AND INCREASING MOISTURE LEVELS. THUS...BRIEF PERIODS OF
MVFR-IFR CIGS/VSBYS EXPECTED IN SHRA/TSRA SATURDAY AND MORE
LIKELY SUNDAY AFTERNOON. SOME DRYING WITH A RETURN TO OVERALL VFR
POSSIBLE MONDAY INTO TUESDAY AS ANOTHER WEAK COOL FRONT SWEEPS IN
FROM THE NW AND TAKES MOST MOISTURE TO THE SE OF THE REGION.
&&
.HYDROLOGY...
AS OF 330 AM EDT FRIDAY...
STEADY LIGHT TO MODERATE RAINFALL WILL SPREAD SLOWLY NORTH THROUGH
THE MORNING WITH PERIODS OF HEAVY RAIN POSSIBLE FROM THE SOUTHERN
BLUE RIDGE...FOOTHILLS EAST ACROSS THE PIEDMONT. RAINFALL TOTALS OF
1-3 INCHES IS EXPECTED ALONG THE ENHANCED UPSLOPE REGIONS OF THE
BLUE RIDGE AND FOOTHILLS MAINLY SOUTH OF ROANOKE WITH A GOOD 1-2
INCHES ELSW OVER THE PIEDMONT SECTIONS OF NORTHWEST NORTH CAROLINA
INTO SOUTHSIDE VIRGINIA BY THIS AFTERNOON. GIVEN THE VERY DRY
ANTECEDENT CONDITIONS OF LATE AND THE OVERALL LACK OF HEAVIER
RAINFALL RATES...WIDESPREAD FLOODING OR FLASH FLOODING IS NOT
EXPECTED BUT LOCALIZED SMALL STREAM AND POOR DRAINAGE FLOODING
COULD OCCUR ESPCLY WHERE HEAVIER DOWNPOURS ARE REALIZED. RAINFALL
TOTALS SHOULD QUICKLY TAPER OFF HEADING INTO FAR WESTERN VIRGINA
AND SE WEST VIRGINIA WHERE ONLY UP TO A HALF INCH LOOKS POSSIBLE
WITH AN INCH OR MORE LIKELY IN AREAS AROUND LYNCHBURG.
&&
.EQUIPMENT...
THE NOAA WEATHER RADIO AT WYTHEVILLE VA...WZ2500...BROADCASTING
ON A FREQUENCY OF 162.450 MHZ...IS OFF THE AIR. TECHNICIANS ARE
WAITING ON DELIVERY OF PARTS TO MAKE REPAIRS. THE EARLIEST THE
RADIO WILL BE WORKING AGAIN IS LATER TODAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/NF
NEAR TERM...JH
SHORT TERM...RCS
LONG TERM...AMS
AVIATION...JH/NF/WP
HYDROLOGY...JH
EQUIPMENT...DS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
338 AM EDT FRI AUG 1 2014
.SYNOPSIS...
AN UPPER TROUGH OF LOW PRESSURE WILL CONTINUE TO RETROGRADE WEST
TO THE MISSISSIPPI RIVER VALLEY...AND THE CENTER OF SURFACE HIGH
PRESSURE WILL SHIFT TO OUR EAST TODAY. AN UPPER DISTURBANCE
TRACKING JUST SOUTHEAST OF THE AREA WILL BRING MORE IN THE WAY OF
WIDESPREAD RAINFALL INTO THIS AFTERNOON. LINGERING MOISTURE IN
THE WAKE OF THIS FEATURE WILL COMBINE WITH HEATING TO RESULT IN
MORE SHOWERS AND STORMS OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 240 AM EDT FRIDAY...
UNUSUAL WIDESPREAD RAIN EVENT FOR MID SUMMER LOOKS IN STORE FOR
MUCH OF TODAY AS SHORTWAVE ENERGY CURRENTLY OVER SOUTHERN S
CAROLINA TRACKS NE CROSSING THE EASTERN PORTIONS OF THE CWA BY
THIS EVENING. THIS WILL CONTINUE TO ENHANCE THE OVERRUNNING OF
WARM/MOIST AIR ON SE FLOW OVERTOP A DEVELOPING COOL WEDGE EARLY
THIS MORNING...WITH SOME DEGREE OF PRECIP SPREADING NORTH AND WEST
ACROSS MUCH OF THE REGION BY 12Z. STILL APPEARS THAT THE HEAVIEST
RAINFALL WILL BE ACROSS SOUTHERN SECTIONS AND ENHANCED ALONG THE
SOUTHERN BLUE RIDGE BY UPSLOPE FLOW OF NEAR 2 INCH PWATS INTO THIS
AFTERNOON. MODEL INIT WAS TOO FAR WEST WITH THE CORE OF HEAVIER
RAINFALL BUT EXPECT THE CURRENT AXIS TO PIVOT MORE NORTH-SOUTH
ORIENTED SIMILAR TO THE LATEST HRRR AS THE WAVE HELPS SHARPEN THE
TROF WHILE BACKING THE FLOW ALOFT THIS MORNING. QUESTION IS
WHETHER OR NOT WILL GET ENOUGH HEAVIER RAINFALL OVER A PROLONGED
PERIOD TO PRODUCE FLOOD ISSUES GIVEN DRY CONDITIONS PER LATEST FFG
SHOWING 6 HOUR AMOUNTS OF 3.5-4.5 INCHES TO CAUSE FLOODING. SINCE
EXPECTING MOST OF THE RAINFALL TO REMAIN MORE STRATIFORM WITH
EMBEDDED HEAVIER DOWNPOURS WONT POST A WATCH OVER THE SW FOR NOW
BUT EXPECT UPSLOPE MAY CAUSE A GOOD 2-3+ INCHES ALONG THE EASTERN
SLOPES.
BEST LIFT SPREADS NE WITH THE WAVE THIS AFTERNOON CAUSING THE SOLID
AXIS OF PRECIP TO SHIFT ACROSS EASTERN/NE SECTIONS DURING THE
AFTERNOON WITH SOME TAPERING TO LIGHTER SHRA WEST/SW. COULD EVEN
SEE A FEW BREAKS DEVELOP FAR WEST ON THE PERIMETER OF THE COOL AIR
OTRW CLOUDY AND VERY COOL TO START AUGUST. HIGHS QUITE TRICKY AS
SOME SPOTS MAY SEE MORE OF A WINTER CAD EVENT WITH TEMPS ONLY
RISING A FEW DEGREES AT MOST ALONG THE BLUE RIDGE WHERE KEEPING IT
IN THE 60S FOR THE MOST PART. THINK SPOTS OVER THE PIEDMONT
INCLUDING SW VA INTO SE WVA MAY BE ABLE TO BUMP VALUES INTO THE
LOW/MID 70S ESPCLY IF THE RAINFALL DIMINISHES A BIT FASTER AND
THINGS BRIGHTEN SLIGHTLY.
IMPULSE EXITS THIS EVENING LEAVING THE REGION WITHIN THE RESIDUAL
WEDGE BUT UNDERNEATH A CONTINUED DIFFLUENT PATTERN ALOFT ON THE
FRONT OF THE 5H TROF. LITTLE UPPER SUPPORT REMAINING OVERNIGHT FOR
MUCH ADDED RAINFALL ESPCLY AFTER MIDNIGHT BUT LIKELY ENOUGH WEAK
UPSLOPE TO KEEP LIKELY OR HIGHER POPS GOING BLUE RIDGE INTO LATE
THIS EVENING. FLOW BEHIND THE DEPARTING WAVE MAY ACTUALLY TURN
WESTERLY ENOUGH TO SHUT OFF SHRA WESTERN HALF LATE SO CUT POPS
BACK TO MAINLY CHANCE AFTER MIDNIGHT WHEN MAY BE MORE DRIZZLE/FOG
OUT EAST. CONTINUED COOL WITH LOWS LIKELY ONLY FALLING A FEW
DEGREES BUT AFTER A CHILLY DAY WONT TAKE MUCH TO GET INTO THE 50S
WEST AND LOW 60S EAST.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
AS OF 314 AM EDT FRIDAY...
A BERMUDA HIGH REMAINS OVER THE WESTERN ATLANTIC WHILE AN UPPER
LEVEL TROUGH IS DRAPED OVER THE MISSISSIPPI VALLEY THIS WEEKEND.
WITH THE FORECAST AREA IN BETWEEN THESE TWO SYNOPTIC
FEATURES...IMPULSES WITH TROPICAL MOISTURE WILL KEEP A GOOD CHANCE
FOR SHOWERS AND SCATTERED THUNDERSTORMS IN THE AREA OVER THE
WEEKEND. COMPARED TO YESTERDAY...MODELS HAVE SHIFTED THE AXIS OF
HEAVY STEADY RAIN EAST ALONG THE COAST. THE FORECAST AREA WILL STILL
SEE A FAIR AMOUNT OF RAIN OVER THE WEEKEND...BUT WILL BE MORE
CONFIDED TO THE AFTERNOON AND EVENING HOURS. DESPITE THE MODELS
TRENDING DRIER...KEEP POPS THROUGH THE ENTIRE PERIOD WITH LOW CHANCE
DURING NON-DIURNAL HEATING HOURS AND HIGH CHANCE-LIKELY DURING THE
AFTERNOON AND EVENING. ALSO WITH THE DRIER MODEL SOLUTIONS...EDGE
TEMPERATURES UP A FEW DEGREES EACH AFTERNOON. DESPITE WARMING THE
FORECAST TEMPERATURES...THEY WILL REMAIN COOLER THAN NORMAL BY AT
LEAST 10F FOR THE FIRST WEEKEND IN AUGUST.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 330 PM EDT THURSDAY...
MONDAY THROUGH WEDNESDAY THE TROFFING IN THE EAST FLATTENS. A
SURFACE COLD FRONT COMES SOUTH THROUGH NEW ENGLAND MONDAY
TUESDAY...BUT WILL ONLY MOVE SO FAR SOUTH WITH THE BOUNDARY PARALLEL
TO THE UPPER FLOW.
THIS WILL KEEP THE FORECAST AREA ON THE WARM UNSTABLE AIR MASS ON
THE SOUTH SIDE OF THE FRONT THROUGH THURSDAY. DEEPEST MOISTURE AND
BEST LIFT WILL BE FOCUSED ALONG THE COAST FRONT ACROSS THE CAROLINAS
AND GEORGIA. NOT SEEING ANY ORGANIZED FORCING FOR THE COUNTY WARNING
AREA.
TEMPERATURES WILL BE NEAR NORMAL THROUGH THE PERIOD.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
AS OF 1245 AM EDT FRIDAY...
FLYING CONDITIONS WILL GRADUALLY DETERIORATE OVERNIGHT INTO EARLY
FRIDAY MORNING AS AN AXIS OF SHOWERS WITH EMBEDDED HEAVY RAIN
SLIDES SLOWLY NORTH...LIKELY COVERING MOST OF THE REGION WITH THE
EXCEPTION OF KLWB BY DAYBREAK. MODELS CONTINUE TO SHOW THIS
SCENARIO WITH WIDESPREAD RAINFALL ESPCLY BLUE RIDGE EAST OVERNIGHT
THROUGH MUCH OF FRIDAY BUT DIFFER ON EXACTLY WHERE THE HEAVIEST
MAY TAKE SHAPE. STILL APPEARS SOUTHERN SECTIONS RUNNING UP ALONG
THE EASTERN SLOPES OF THE SOUTHERN BLUE RIDGE LOCATIONS WILL SEE
THE HEAVIEST RAINFALL INCLUDING WIDESPREAD MVFR TO IFR LATER
TONIGHT THROUGH MUCH OF FRIDAY...AND PERHAPS INTO FRIDAY NIGHT.
WESTERN LOCATIONS SUCH AS KBLF/KLWB MAY BREAK BACK OUT INTO VFR
AFTER EARLY RAINFALL GIVEN DOWNSLOPE AND PASSAGE OF DEEPER
MOISTURE TO THE EAST SO WENT CLOSER TO THE LESS PESSIMISTIC GFS
THERE. ELSW STAYING CLOSER TO THE LOWER CIGS SUGGESTED BY THE NAM
GIVEN EASTERLY FLOW ONCE THINGS BECOME SATURATED. ALSO PERIODS OF
MVFR VSBYS LIKELY BY EARLY FRIDAY WITH POSSIBLE IFR AT TIMES IN
HEAVIER RAIN/FOG NEAR THE BLUE RIDGE IN SPOTS SUCH AS KBCB/KROA.
DESPITE THE EXODUS OF THE WAVE FRIDAY EVENING...LINGERING WEDGE
AND DIFFLUENCE ALOFT LIKELY TO KEEP AT LEAST SOME SPOTTY SHOWERS
AROUND WHICH MAY HOLD MVFR TO IFR CIGS ALONG WITH FOG IN PLACE
FRIDAY NIGHT.
EXTENDED AVIATION DISCUSSION...
THE BROAD UPPER TROUGH OF LOW PRESSURE WILL LINGER ACROSS THE
EASTERN UNITED STATES THROUGH SUNDAY CONTINUING TO RETROGRADE
FROM THE EASTERN/CENTRAL GREAT LAKES TO THE WESTERN GREAT LAKES BY
THE WEEKEND.
FOR SATURDAY AND SUNDAY...THE AIR MASS WILL SLOWLY BECOME WARMER
AND MORE UNSTABLE. SCT SHRA/TSRA EXPECTED AGAIN SATURDAY WITH
ONLY LIMITED INSTABILITY EVIDENT. FOR SUNDAY...BETTER CHANCE OF
TSRA WITH BETTER INSTABILITY ACROSS MUCH OF THE CWA...SW FLOW
ALOFT...AND INCREASING MOISTURE LEVELS. THUS...BRIEF PERIODS OF
MVFR-IFR CIGS/VSBYS EXPECTED IN SHRA/TSRA SATURDAY AND MORE
LIKELY SUNDAY AFTERNOON. SOME DRYING WITH A RETURN TO OVERALL VFR
POSSIBLE MONDAY INTO TUESDAY AS ANOTHER WEAK COOL FRONT SWEEPS IN
FROM THE NW AND TAKES MOST MOISTURE TO THE SE OF THE REGION.
&&
.HYDROLOGY...
AS OF 330 AM EDT FRIDAY...
STEADY LIGHT TO MODERATE RAINFALL WILL SPREAD SLOWLY NORTH THROUGH
THE MORNING WITH PERIODS OF HEAVY RAIN POSSIBLE ALONG THE SOUTHERN
BLUE RIDGE AND ACROSS THE PIEDMONT. ADDED RAINFALL OF 2-3 INCHES
IS EXPECTED ALONG THE ENHANCED UPSLOPE REGIONS OF THE BLUE RIDGE
MAINLY SOUTH OF ROANOKE WITH A GOOD 1-2 INCHES ELSW OVER THE
FOOTHILLS AND PIEDMONT SECTIONS OF NORTHWEST NORTH CAROLINA INTO
SOUTHSIDE VIRGINIA BY THIS AFTERNOON. GIVEN THE VERY DRY
ANTECEDENT CONDITIONS OF LATE AND THE OVERALL LACK OF HEAVIER
RAINFALL RATES...WIDESPREAD FLOODING OR FLASH FLOODING IS NOT
EXPECTED BUT LOCALIZED SMALL STREAM AND POOR DRAINAGE FLOODING
COULD OCCUR ESPCLY WHERE HEAVIER DOWNPOURS ARE REALIZED. RAINFALL
TOTALS SHOULD QUICKLY TAPER OFF HEADING INTO FAR WESTERN VIRGINA
AND SE WEST VIRGINIA WHERE ONLY UP TO A HALF INCH LOOKS POSSIBLE
WITH AN INCH OR MORE LIKELY IN AREAS AROUND LYNCHBURG.
&&
.EQUIPMENT...
THE NOAA WEATHER RADIO AT WYTHEVILLE VA...WZ2500...BROADCASTING
ON A FREQUENCY OF 162.450 MHZ...IS OFF THE AIR. TECHNICIANS ARE
WAITING ON DELIVERY OF PARTS TO MAKE REPAIRS. THE EARLIEST THE
RADIO WILL BE WORKING AGAIN IS LATER TODAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/NF
NEAR TERM...JH
SHORT TERM...RCS
LONG TERM...AMS
AVIATION...JH/NF/WP
HYDROLOGY...JH
EQUIPMENT...DS
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
244 PM MDT FRI AUG 1 2014
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
SHOWERS WITH A FEW EMBEDDED TSTORMS ARE DEVELOPING JUST NORTH AND
NORTHWEST OF THE CWA THIS AFTERNOON IN ADVANCE OF A WEAK SHORTWAVE
EVIDENT ON WATER VAPOR MOVING SOUTHEAST ACROSS WYOMING. STILL EXPECT
SOME OF THIS ACTIVITY TO TREK SOUTHWARD INTO THE CWA WHILE ALSO
DEVELOPING ALONG THE PINE RIDGE AND MOUNTAINS OF SOUTHEAST WYOMING.
THUS MAINTAINED A SLIGHT CHANCE FOR ISOLATED THUNDER IN THESE AREAS
THROUGH THE EARLY EVENING. EXTENDED THE RISK SLIGHTLY FURTHER SOUTH
FROM THE PREVIOUS FORECAST TO THE NORTH PLATTE RIVER VALLEY TO LINE
UP WITH DEVELOPING TOWERING CU SEEN ON VIS SAT IMAGERY...IN ADDITION
TO THE LATEST HRRR GUIDANCE. LATEST MESOANALYSIS SHOWS MINIMAL CAPE
IN PLACE ACROSS THE AREA THO...SO NOT EXPECTING THIS ACTIVITY TO
BECOME STRONG NOR WIDESPREAD THIS AFTERNOON.
THE UPPER RIDGE AXIS WILL SLOWLY SHIFT EASTWARD TOWARD THE ROCKIES
TONIGHT AND SATURDAY...WITH THE MIDLEVELS LOOKING OVERALL LESS
ENERGETIC THAN TODAY. A WEAK FRONT LOOKS TO DROP SOUTH ACROSS THE
AREA ON SATURDAY...WITH PERHAPS A FEW SHOWERS AND WEAK STORMS
DEVELOPING OVER THE MOUNTAINS IN THE AFTERNOON AS WINDS WILL BECOME
MORE OF AN UPSLOPE COMPONENT BEHIND THE FRONT. WITH MINIMAL UPPER
SUPPORT ANTICIPATED...AM NOT VERY CONFIDENT COVERAGE WILL SHIFT INTO
THE PLAINS...SO CONFINED CHANCES FOR THUNDER TO THE MOUNTAINS.
CONDITIONS WILL REMAIN WARM WITH H7 TEMPS RANGING FROM 10 TO 14C.
SIMILAR CONDITIONS ARE EXPECTED FOR SUNDAY WITH TEMPS A FEW DEGREES
WARMER AS THE THERMAL RIDGE AXIS APPROACHES FROM THE WEST.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 300 PM MDT FRI AUG 1 2014
MODELS IN DECENT AGREEMENT WITH THE OVERALL PATTERN THROUGH NEXT
WEEK...SHOWING MONSOON MOISTURE INCREASING OVER THE FORECAST AREA
AS THE MID TO UPPERLEVEL FLOW BECOMES MORE SOUTHWESTERLY AHEAD OF
A WEAK SHORTWAVE ACROSS THE EASTERN PACIFIC. AS FOR INDIVIDUAL
DISTURBANCES/SHORTWAVE ENERGY MOVING NORTHWARD AND EVENTUALLY
EASTWARD ACROSS THE AREA...MODELS SHOW POOR CONSISTENCY AND ARE
OUT OF SYNC WITH THE MOVEMENT AND TIMING. THE ECMWF IS INITIALLY
18 TO 24 HOURS LATER THAN THE GFS AND GEM...WITH THE GEM ALSO
MUCH WEAKER WITH THE FIRST DISTURBANCE ON TUESDAY THAN THE OTHER
MODELS. THIS CONTINUES INTO LATE NEXT WEEK WITH THE MAIN SHORTWAVE
TROUGH AS IT MOVES NORTHEAST FROM SOUTHERN CALIFORNIA TO THE
CENTRAL ROCKY MOUNTAINS. THIS IS MAKING POP AND WEATHER FORECASTS
DIFFICULT GOING INTO NEXT WEEK IN TERMS OF WHICH DAYS HAVE THE
HIGHEST POTENTIAL FOR WIDESPREAD RAINFALL AND THUNDERSTORM
OUTBREAKS. THEREFORE...KEPT POP NO HIGHER THAN 40 PERCENT OUTSIDE
OF THE MOUNTAINS DUE TO LOWER THAN AVERAGE CONFIDENCE. DO EXPECT
SHOWERS AND TSTORMS NEARLY EVERYDAY HOWEVER. TUESDAY APPEARS TO BE
THE BEST DAY FOR WIDESPREAD CONVECTION AS THE FIRST DISTURBANCE
MOVES ACROSS WYOMING IN SOME FORM. WEAK WINDS ALOFT MAY RESULT IN
VERY HEAVY RAINFALL AND FLASH FLOODING THROUGH TUESDAY NIGHT.
TEMPERATURES WILL NOT CHANGE MUCH WITH A SUBTROPICAL AIRMASS OVER
THE REGION. EXPECT HIGHS IN THE UPPER 70S TO UPPER 80S...WHICH
WILL BE NEAR OR SLIGHTLY LOWER THAN AVERAGE. KEPT TEMPERATURES A
FEW DEGREES BELOW MOS DUE TO AN OBSERVED WARM BIAS WITH SOUTH TO
SOUTHEAST WINDS ACROSS THE HIGH PLAINS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH SATURDAY MORNING)
ISSUED AT 1135 AM MDT FRI AUG 1 2014
VFR EXPECTED OVER ALL TERMINALS THROUGH THE PERIOD. ISOLATED
SHOWERS AND THUNDERSTORMS POSSIBLE MAINLY OVER THE SOUTHEAST WYOMING
MTNS THIS AFTERNOON INTO THIS EVENING. WINDS WILL BE LIGHT OUT OF
THE SOUTH OR SOUTHEAST INTO LATE THIS EVENING.
&&
.FIRE WEATHER...
WARM AND MOSTLY DRY CONDITIONS ARE EXPECTED FOR THE DISTRICT
THROUGH THE WEEKEND AS AN UPPER LEVEL RIDGE OF HIGH PRESSURE REMAINS
OVER THE REGION. MINIMUM HUMIDITIES ARE EXPECTED TO DROP INTO THE
UPPER TEENS TO UPPER 20S...WITH 30 PERCENTS IN THE MOUNTAINS. WINDS
WILL REMAIN LIGHT OVERALL...WITH A FEW LOCATIONS ALONG AND WEST OF
THE LARAMIE RANGE GUSTING 15 TO 25 MPH IN THE AFTERNOONS. THERE
REMAINS A SLIGHT CHANCE FOR ISOLATED THUNDERSTORMS THROUGH EARLY
THIS EVENING FOR LOCATIONS WEST OF THE LARAMIE RANGE AND ALSO ALONG
THE PINE RIDGE. THIS ACTIVITY IS NOT EXPECTED TO PRODUCE MUCH
RAIN...WITH AMOUNTS OF ONLY A COUPLE HUNDREDTHS TO ONE TENTH OF AN
INCH. A MUCH BETTER CHANCE OF MORE SUBSTANTIAL PRECIPITATION WILL
OCCUR MONDAY THRU WEDNESDAY OF NEXT WEEK.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...RJM
LONG TERM...TJT
AVIATION...TJT
FIRE WEATHER...RJM
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1135 AM MDT FRI AUG 1 2014
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 334 AM MDT FRI AUG 1 2014
THE PATTERN WILL BE FAIRLY STAGNANT THRU THE PERIOD. MORNING WV
IMAGERY DEPICTS UPPER RIDGE AXIS EXTENDING FROM SRN CALIFORNIA
NORTH INTO THE NRN ROCKIES. THIS WILL GRADUALLY PROGRESS EAST AND
AMPLIFY SOMEWHAT THRU THE WEEKEND...WITH THE RIDGE AXIS REACHING
THE ENTIRE SPINE OF THE ROCKIES BY SUNDAY. REGIONAL RADARS ARE
EMPTY THIS MORNING WITH THE LAST CONVECTION DISSIPATING OVR ERN
MONTANA OVER THE PAST FEW HOURS. QUESTION MARK REMAINS ON WHETHER
OR NOT CONVECTION WILL BE ABLE TO GET GOING TODAY...ESPECIALLY
GIVEN ITS INABILITY TO INITIATE ON THURSDAY. 00Z MODELS ARE PALTRY
WITH QPF OUTPUT TODAY COMPARED TO RUNS 24 HOURS AGO. WV IMAGERY
DOES SHOW A POCKET OF MOISTURE THAT WILL DRIFT SE THRU PORTION OF
THE CWFA TODAY. THE MOISTURE WAS ABLE TO SPARK SOME WK
THUNDERSTORM ACTIVITY IN YNP YESTERDAY. LATEST HRRR SUPPORTS THIS
IDEA AS WELL... DEVELOPING AT LEAST SOME WK UPDRAFTS OVR EAST
CENTRAL WYOMING/NRN NEBRASKA PANHANDLE BY EARLY AFTERNOON. WILL
KEEP THE INHERITED PRECIP CHANCES GOING FOR THIS AFTERNOON...
MAINLY ALONG AND WEST OF THE LARAMIE RANGE AND IN AREAS NR THE
PINE RIDGE. IF CONVECTION DOES MATERIALIZE...IT WILL BE WEAK AND
DISSIPATE EARLY THIS EVENING. HIGH TEMPERATURES WILL BE 3-5F
WARMER TODAY EAST OF THE LARAMIE RANGE.
THE WEEKEND LOOKS DRY ACROSS ALL LOWER ELEVATIONS AS TEMPERATURES
WARM ALOFT AND SUBSIDENCE DOMINATES. THERE MAY BE SOME WEAK DAILY
CONVECTION OVR THE SNOWY/SIERRA MADRE RANGES...BUT THAT WILL BE
ABOUT IT. TEMPERATURES WILL CONTINUE TO WARM SLOWLY THRU THE
WEEKEND..REACHING THE 80S AND LOW 90S FOR ALL LOCATIONS BELOW 7KFT
SUNDAY.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 334 AM MDT FRI AUG 1 2014
MONSOONAL MOISTURE SHOULD SPREAD OVER MUCH OF THE CWA BEGINNING
MONDAY THOUGH CONVECTION SHOULD REMAIN GENERALLY WEST OF THE CWA.
MORE WIDESPREAD ACTIVITY EXPECTED ACROSS THE CWA TUESDAY WITH AN
UPPER TROF MOVING EAST ACROSS THE AREA THROUGH TUESDAY NIGHT
HELPING TO ENHANCE SHOWERS AND ISOLATED TSTMS. AT LEAST ISOLATED
CONVECTION SHOULD PERSIST WEDS THOUGH BETTER SUPPORT LOOKS TO
SHIFT NORTH OF THE CWA AT THAT TIME. MAINLY DRY WEATHER EXPECTED
ON FRIDAY AS MONSOONAL MOISTURE GETS CUT OFF FOR THE MOST PART ONCE
AGAIN. TEMPERATURES WILL BE MILD TO WARM DURING THE PERIOD WITH THE
COOLEST DAY LIKELY BEING TUESDAY WHEN CLOUDS AND PCPN WILL BE MOST
PREVALENT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH SATURDAY MORNING)
ISSUED AT 1135 AM MDT FRI AUG 1 2014
VFR EXPECTED OVER ALL TERMINALS THROUGH THE PERIOD. ISOLATED
SHOWERS AND THUNDERSTORMS POSSIBLE MAINLY OVER THE SOUTHEAST WYOMING
MTNS THIS AFTERNOON INTO THIS EVENING. WINDS WILL BE LIGHT OUT OF
THE SOUTH OR SOUTHEAST INTO LATE THIS EVENING.
&&
.FIRE WEATHER...
ISSUED AT 334 AM MDT FRI AUG 1 2014
LIMITED FIRE WEATHER CONCERNS SEEN THROUGH THE MIDDLE OF NEXT
WEEK. A RIDGE OF HIGH PRESSURE THROUGH THE WEEKEND WILL RESULT IN
RELATIVELY LIGHT AND WINDS AND SLIGHTLY ABOVE NORMAL TEMPERATURES.
TODAY WILL SEE A SMALL CHANCE FOR AFTERNOON AND EARLY EVENING
SHOWER/THUNDERSTORM ACTIVITY MAINLY WEST OF THE LARAMIE RANGE AND
NEAR THE PINE RIDGE. ALTHOUGH ANY CHANCE FOR WETTING RAIN WILL BE
EXTREMELY LOW. TEMPERATURES WILL GRADUALLY WARM THROUGH THE
WEEKEND WITH THE 80 DEGREE TEMPERATURE LINE REACHING AROUND 6000
FEET. MINIMUM HUMIDITIES SHOULD ONLY FALL INTO THE 20 TO 30
PERCENT RANGE THROUGH THE WEEKEND...WHICH WILL HELP KEEP FIRE
WEATHER CONCERNS AT BAY. THE NEXT CHANCE FOR MORE SUBSTANTIAL
PRECIPITATION RETURNS MON AND ESPECIALLY TUE OF NEXT WEEK.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...HAHN
LONG TERM...RE
AVIATION...TJT
FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
334 AM MDT FRI AUG 1 2014
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 334 AM MDT FRI AUG 1 2014
THE PATTERN WILL BE FAIRLY STAGNANT THRU THE PERIOD. MORNING WV
IMAGERY DEPICTS UPPER RIDGE AXIS EXTENDING FROM SRN CALIFORNIA
NORTH INTO THE NRN ROCKIES. THIS WILL GRADUALLY PROGRESS EAST AND
AMPLIFY SOMEWHAT THRU THE WEEKEND...WITH THE RIDGE AXIS REACHING
THE ENTIRE SPINE OF THE ROCKIES BY SUNDAY. REGIONAL RADARS ARE
EMPTY THIS MORNING WITH THE LAST CONVECTION DISSIPATING OVR ERN
MONTANA OVER THE PAST FEW HOURS. QUESTION MARK REMAINS ON WHETHER
OR NOT CONVECTION WILL BE ABLE TO GET GOING TODAY...ESPECIALLY
GIVEN ITS INABILITY TO INITIATE ON THURSDAY. 00Z MODELS ARE PALTRY
WITH QPF OUTPUT TODAY COMPARED TO RUNS 24 HOURS AGO. WV IMAGERY
DOES SHOW A POCKET OF MOISTURE THAT WILL DRIFT SE THRU PORTION OF
THE CWFA TODAY. THE MOISTURE WAS ABLE TO SPARK SOME WK
THUNDERSTORM ACTIVITY IN YNP YESTERDAY. LATEST HRRR SUPPORTS THIS
IDEA AS WELL... DEVELOPING AT LEAST SOME WK UPDRAFTS OVR EAST
CENTRAL WYOMING/NRN NEBRASKA PANHANDLE BY EARLY AFTERNOON. WILL
KEEP THE INHERITED PRECIP CHANCES GOING FOR THIS AFTERNOON...
MAINLY ALONG AND WEST OF THE LARAMIE RANGE AND IN AREAS NR THE
PINE RIDGE. IF CONVECTION DOES MATERIALIZE...IT WILL BE WEAK AND
DISSIPATE EARLY THIS EVENING. HIGH TEMPERATURES WILL BE 3-5F
WARMER TODAY EAST OF THE LARAMIE RANGE.
THE WEEKEND LOOKS DRY ACROSS ALL LOWER ELEVATIONS AS TEMPERATURES
WARM ALOFT AND SUBSIDENCE DOMINATES. THERE MAY BE SOME WEAK DAILY
CONVECTION OVR THE SNOWY/SIERRA MADRE RANGES...BUT THAT WILL BE
ABOUT IT. TEMPERATURES WILL CONTINUE TO WARM SLOWLY THRU THE
WEEKEND..REACHING THE 80S AND LOW 90S FOR ALL LOCATIONS BELOW 7KFT
SUNDAY.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 334 AM MDT FRI AUG 1 2014
MONSOONAL MOISTURE SHOULD SPREAD OVER MUCH OF THE CWA BEGINNING
MONDAY THOUGH CONVECTION SHOULD REMAIN GENERALLY WEST OF THE CWA.
MORE WIDESPREAD ACTIVITY EXPECTED ACROSS THE CWA TUESDAY WITH AN
UPPER TROF MOVING EAST ACROSS THE AREA THROUGH TUESDAY NIGHT
HELPING TO ENHANCE SHOWERS AND ISOLATED TSTMS. AT LEAST ISOLATED
CONVECTION SHOULD PERSIST WEDS THOUGH BETTER SUPPORT LOOKS TO
SHIFT NORTH OF THE CWA AT THAT TIME. MAINLY DRY WEATHER EXPECTED
ON FRIDAY AS MONSOONAL MOISTURE GETS CUT OFF FOR THE MOST PART ONCE
AGAIN. TEMPERATURES WILL BE MILD TO WARM DURING THE PERIOD WITH THE
COOLEST DAY LIKELY BEING TUESDAY WHEN CLOUDS AND PCPN WILL BE MOST
PREVALENT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 334 AM MDT FRI AUG 1 2014
VFR EXPECTED OVER ALL TERMINALS THROUGH THE PERIOD. ISOLATED
SHOWERS AND THUNDERSTORMS POSSIBLE MAINLY OVER THE SOUTHEAST
WYOMING MTNS THIS AFTERNOON INTO THIS EVENING. COVERAGE WILL BE
VERY LIMITED HOWEVER.
&&
.FIRE WEATHER...
ISSUED AT 334 AM MDT FRI AUG 1 2014
LIMITED FIRE WEATHER CONCERNS SEEN THROUGH THE MIDDLE OF NEXT
WEEK. A RIDGE OF HIGH PRESSURE THROUGH THE WEEKEND WILL RESULT IN
RELATIVELY LIGHT AND WINDS AND SLIGHTLY ABOVE NORMAL TEMPERATURES.
TODAY WILL SEE A SMALL CHANCE FOR AFTERNOON AND EARLY EVENING
SHOWER/THUNDERSTORM ACTIVITY MAINLY WEST OF THE LARAMIE RANGE AND
NEAR THE PINE RIDGE. ALTHOUGH ANY CHANCE FOR WETTING RAIN WILL BE
EXTREMELY LOW. TEMPERATURES WILL GRADUALLY WARM THROUGH THE
WEEKEND WITH THE 80 DEGREE TEMPERATURE LINE REACHING AROUND 6000
FEET. MINIMUM HUMIDITIES SHOULD ONLY FALL INTO THE 20 TO 30
PERCENT RANGE THROUGH THE WEEKEND...WHICH WILL HELP KEEP FIRE
WEATHER CONCERNS AT BAY. THE NEXT CHANCE FOR MORE SUBSTANTIAL
PRECIPITATION RETURNS MON AND ESPECIALLY TUE OF NEXT WEEK.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...HAHN
LONG TERM...RE
AVIATION...RE
FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
340 AM MDT SUN AUG 3 2014
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 339 AM MDT SUN AUG 3 2014
MOISTURE CONTINUES LIFTING NORTHWARD INTO THE FOUR CORNERS REGION
THIS MORNING WITH A FEW SHOWERS AND ISOLATED THUNDERSTORMS FIRING
ALONG WESTWARD PROPAGATING WAVE. HRRR HAS A FAIRLY GOOD HANDLE ON
THIS ACTIVITY AND INDICATES A BREAK ARRIVING AFTER 9 AM. CELLS
QUICKLY REFIRE BY EARLY THIS AFTERNOON AS A STRONGER WAVE LIFTS
SLOWLY NORTH OUT OF ARIZONA AND ACROSS WESTERN UTAH. NEW MODEL
RUNS CONTINUE TO SLIDE THIS WAVE A BIT TO OUR WEST...RESULTING IN
BEST DYNAMIC FORCING ALONG AND TO THE WEST OF OUR EASTERN MOST
UTAH ZONES. WITH EDGE OF DEEPER MOISTURE ROTATING IN AND FORCING
FROM APPROACHING WAVE...EXPECT POTENTIAL FOR HEAVY RAIN AND FLASH
FLOODING WILL BE ON THE RISE LATE THIS AFTERNOON AND THROUGH THE
EVENING HOURS...MAINLY ACROSS SOUTHEAST UTAH. FCST PRECIPITABLE
WATER VALUES EXCEED 1.25 INCHES...OR CLOSE TO 3 STANDARD
DEVIATIONS ABOVE NORMAL FOR THIS TIME OF YEAR. K INDEX VALUES ALSO
ECLIPSING 40...INDICATING SUFFICIENTLY DEEP MOISTURE AND COMMON
DURING FLASH FLOODS EVENTS. WILL GO AHEAD AND ISSUE A FLASH FLOOD
WATCH FOR MUCH OF SOUTHEAST UTAH BEGINNING AROUND MID AFTERNOON
AND CONTINUING UNTIL MIDNIGHT TONIGHT WHERE LOCAL RAINFALL AMOUNTS
MAY EXCEED AN INCH IN A SHORT PERIOD OF TIME.
ELSEWHERE...EXPECT A FAIRLY QUIET START TO THE DAY AS WE AWAIT THE
ARRIVAL OF THE DEEPER MOISTURE. SHOULD SEE SHOWERS AND
THUNDERSTORMS FIRE OVER THE SAN JUANS BY EARLY THIS AFTERNOON AND
GRADUALLY FILL IN AND LIFT NORTH AS THE DAY PROGRESSES. WITH
INCREASING MOISTURE...SURFACE AND ALOFT...AND INCREASED CLOUD
COVER...TEMPS WILL BE DOWN A COUPLE DEGREES FROM READINGS
YESTERDAY.
THE POSSIBILITY OF LOCALLY HEAVY RAIN IS PRESENT TONIGHT AND MONDAY.
MOISTURE CONTINUES TO SPREAD NORTH ACROSS THE FORECAST AREA TONIGHT.
PRECIPITABLE WATER VALUES RUNNING 1+ INCH WITH SURFACE DEWPOINTS
RISING INTO THE 50S AS THE LOWER LEVELS MOISTENS...BOTH COMPONENTS
FOR AN INCREASED CHANCE OF LOCALLY HEAVY RAIN WITH THE ADDED CONCERN
OF POSSIBLE LOCALIZED FLOODING AT NIGHT WHEN IT IS MORE DIFFICULT TO
SEE. MODELS KEEP THE MAIN UPPER LOW CIRCULATION OVER WESTERN NV...
BUT THE NAM/GFS SHOW AN EJECTING SHORTWAVE LIFTING ACROSS SUNDAY
EVENING. SOME UNCERTAINTY IN TIMING AND EASTWARD EXTENT OF ITS
TRACK...BUT SHOULD IT MATERIALIZE IT COULD CONTRIBUTE TO NOCTURNAL
CONVECTION ACROSS ERN UT INTO WRN CO. BLENDED IN 25% OF THE 21Z SREF
TO BUMP UP THE CHANCE OF RAIN FOR MOST AREAS TONIGHT.
40KT SPEED MAX AT 300 MB SLIDES OVERHEAD MONDAY AFTERNOON FOR
CONTINUED SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. CLOUDS
AND SHOWERS WILL KEEP TEMPS BELOW NORMAL.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 339 AM MDT SUN AUG 3 2014
THE UPPER LEVEL DISTURBANCE EXITS WRN CO TO THE NE BY LATE MONDAY
EVENING. MAIN LOW STILL OVER NRN CA/NRN NV BY TUE MORNING...WITH
ANOTHER TROUGH ROTATING AROUND IT AND POSSIBLY LIFTING ACROSS OUR
AREA TOWARD 12Z TUE. NOT CONFIDENT IN THESE FEATURES OR THEIR
TIMING...SO WILL KEEP A CHANCE OF SHOWERS AND THUNDERSTORMS PRESENT
TUESDAY.
MONSOONAL FLOW GETS CUTOFF WEDNESDAY WITH HIGH PRESSURE BUILDING
OVER THE CENTRAL ROCKIES. RIDGE AXIS SPLITS COLORADO WITH
SOUTHWEST FLOW BECOMING ESTABLISHED BY WEDNESDAY AFTERNOON. WILL
CARRY LOW POPS FOR MOUNTAIN CONVECTION THAT WORKS ON LINGERING LOW
LEVEL MOISTURE...OTHERWISE A DRY DAY APPEARS IN STORE. THE RIDGE
SLIDES EAST THURSDAY AS A PACIFIC SYSTEM PUSHES ACROSS THE
NORTHERN GREAT BASIN. THIS WILL BRING ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS TO EASTERN UTAH AND WESTERN COLORADO THURSDAY AND
FRIDAY...ALTHOUGH COVERAGE IS NOT EXPECTED TO BE AS WIDESPREAD AND
STORMS WILL NOT GENERATE AS MUCH RAINFALL WITH PRECIPITABLE WATER
VALUES UNDER THREE QUARTERS OF AN INCH. HOWEVER...COOLING ALOFT
AND WEAK TO MODERATE SHEAR PROFILE COULD TRIGGER A FEW STRONGER
STORMS. ONCE THIS WAVE EXITS LATE FRIDAY...RIDGING ONCE AGAIN SETS
UP OVER THE ROCKIES WITH TROUGHING ALONG THE WEST COAST...KEEPING
EASTERN UTAH AND WESTERN COLORADO CUTOFF FROM THE DEEPER MONSOONAL
MOISTURE TO OUR SOUTH. TEMPS WILL BE MODERATE UPWARD THROUGH THE
PERIOD WITH AFTERNOON HIGHS CLIMBING BACK TO NORMAL FOR THIS TIME
OF SEASON.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 339 AM MDT SUN AUG 3 2014
SHOWERS AND THUNDERSTORMS WILL GRADUALLY SPREAD NORTH AND EAST
ACROSS EASTERN UTAH AND WESTERN COLORADO TODAY AS DEEPER MOISTURE
LIFTS NORTH. A STRONGER DISTURBANCE ARRIVES LATE THIS AFTERNOON
AND EVENING. THIS WILL ENHANCE SHOWERS AND THUNDERSTORMS...WITH
SOME STORMS PRODUCING VERY HEAVY RAINFALL AND GUSTY WINDS TO 40
MPH. EXPECT FREQUENT MOUNTAIN OBSCURATIONS AFTER 19Z THIS
AFTERNOON WITH LOCAL MVFR CIGS AND VSBYS NEAR THE STRONGEST
STORMS. ALL TERMINAL SITES WILL SEE AT LEAST A 50 PERCENT CHANCE
OF BEING IMPACTED BETWEEN 19Z AND 06Z TONIGHT.
&&
.HYDROLOGY...
ISSUED AT 339 AM MDT SUN AUG 3 2014
DEEP SURGE OF MONSOONAL MOISTURE WILL LIFT NORTH AND WEST ACROSS
EASTERN UTAH AND WESTERN COLORADO THIS AFTERNOON AND TONIGHT. AT
THE SAME TIME...A STRONG UPPER LEVEL DISTURBANCE WILL MOVE INTO
THE AREA BY 3 PM MDT...RESULTING IN RAPID DEVELOPMENT OF SHOWERS
AND HEAVY RAIN PRODUCING THUNDERSTORMS...ESPECIALLY ACROSS
PORTIONS OF SOUTHEAST UTAH. AS A RESULT...A FLASH FLOOD WATCH HAS
BEEN ISSUED FOR MUCH OF SOUTHEAST UTAH BEGINNING AT 3 PM THIS
AFTERNOON AND CONTINUING UNTIL MIDNIGHT TONIGHT. RAINFALL RATES
EXCEEDING ONE INCH PER HOUR CAN BE EXPECTED AND MAY LEAD TO FLASH
FLOODING OF SLOT CANYONS AND AREAS NEAR OLD FIRE SCARS. ARCHES AND
CANYONLANDS NATIONAL PARKS ARE BOTH INCLUDED IN THIS FLASH FLOOD
WATCH.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...FLASH FLOOD WATCH FROM 3 PM MDT THIS AFTERNOON THROUGH THIS
EVENING FOR UTZ022-025-027-029.
&&
$$
SHORT TERM...JDC/JAD
LONG TERM...JAD/JDC
AVIATION...JDC
HYDROLOGY...JDC
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
440 AM EDT SUN AUG 3 2014
.SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A SIMILAR LONGWAVE PATTERN
TO 24 HOURS AGO...WITH RIDGING ACROSS THE WESTERN HALF OF THE CONUS
AND PERSISTENT TROUGHING OVER MUCH OF THE EAST. UPPER LEVEL PATTERN
OVER THE FLORIDA PENINSULA IS RATHER UNDEFINED EARLY THIS MORNING
BETWEEN THE MAIN LONGWAVE TROUGH TO OUR NORTH...AND A WEAK IMPULSE
APPROACHING FROM OVER THE BAHAMAS. THE OVERALL ATMOSPHERE IS QUITE
MOIST REGION WIDE AHEAD OF THIS IMPULSE WITH PW VALUES HOLDING IN
THE VICINITY OF 2". THE SURFACE REFLECTION OF THIS APPROACHING
IMPULSE IS SEEN AS A WEAK INVERTED TROUGH ACROSS SOUTH FLORIDA AND
THE FL STRAITS...AND IS PROGGED BY JUST ABOUT ALL NWP GUIDANCE
MEMBERS TO CLOSE OFF INTO A WEAK SURFACE LOW OVER THE PENINSULA
TODAY AND THEN DRIFT NORTHWARD THROUGH TONIGHT.
REGIONAL RADARS A FAIRLY QUIET THIS EARLY MORNING WITH JUST A FEW
SHOWERS OVER THE COASTAL WATERS OF THE EASTERN GULF OF MEXICO...AND
A SCATTERING OF SHOWERS MOVING ONSHORE THE FLORIDA EAST COAST.
THESE SHOWERS WILL HAVE A HARD TIME REACHING OUR FORECAST AREA THE
NEXT SEVERAL HOURS AS THEY TEND TO DISSIPATE WITH INLAND
PENETRATION. CAN NOT RULE OUT A BRIEF SPRINKLE IN FAR EASTERN
POLK/HIGHLANDS COUNTIES EARLY THIS MORNING...BUT THAT SHOULD BE JUST
ABOUT IT.
&&
.SHORT TERM (TODAY THROUGH MONDAY)...
TODAY...
UNFORTUNATELY THE SYNOPTIC PATTERN IS NOT ONE THAT SUPPORTS A VERY
SPATIALLY OR TEMPORALLY DETAILED FORECAST PACKAGE. THE ATMOSPHERE IS
PRETTY FAVORABLE FOR DEEP CONVECTION WITH THE DEEP MOISTURE...AND
LITTLE TO NO DRY AIR LAYERS FOR THE CONVECTIVE UPDRAFTS TO FIGHT. IN
ADDITION...THE WEAK LOW FEATURE TRAVERSING THE AREA TODAY WILL ADD A
BROAD LOW LEVEL FOCUS FOR ASCENT AND INTERACT WITH DEVELOPING
SEA-BREEZE BOUNDARIES TO GIVE US ANOTHER FAIRLY ACTIVE SECOND HALF
OF THE DAY IN TERMS OF CONVECTION. DO FEEL...MUCH OF THE MORNING
WILL BE ON THE QUIET SIDE...HOWEVER ONCE WE GET SOME DECENT SURFACE
HEATING...IT WILL NOT TAKE MUCH TO GET THE STORMS BUBBLING UP.
AS MENTIONED ABOVE...THE BROAD LOW LEVEL FOCUS FOR ASCENT ACROSS THE
REGION MAKES IT DIFFICULT TO GET VERY DETAILED WITH THE TIMING OF
STORMS FOR ANY ONE LOCATION. THE BEST RAIN CHANCES (> 60%) DO APPEAR
TO BE ALONG AND EAST OF THE I-75 CORRIDOR AS THE SEA-BREEZE SHOULD
BE ABLE TO MAKE SOME PROGRESS INLAND. THEREFORE...THE BEST CHANCES
FOR A DRY AFTERNOON WOULD BE CLOSE TO THE COAST FROM MANATEE COUNTY
NORTHWARD. THE FORECAST UNCERTAINLY STILL SUGGESTS KEEPING A CHANCE
POP FOR THESE COASTAL AREAS AS WELL...AND THE DAY SHIFT CAN SEE HOW
THINGS ARE EVOLVING LATER THIS MORNING AND MAKE ANY NECESSARY
ADJUSTMENTS.
SIMILAR TO SATURDAY...STORMS THAT DO DEVELOP WILL BE SLOW
MOVERS...AND COMBINED WITH THE MOIST ATMOSPHERE WILL BE CAPABLE OF
SOME LOCALLY HEFTY RAINFALL TOTALS. WILL HAVE TO WATCH CLOSELY AREAS
THAT SAW SIGNIFICANT RAINFALL ON SATURDAY AND MAY NOT BE ABLE TO
HANDLE THE RUNOFF AS WELL IN CASE THESE SAME AREA FIND THEMSELVES
UNDER SLOW MOVING STORMS ONCE AGAIN.
MONDAY...
STARTING OUT THE WORK WEEK...WE WILL FIND THE WEAK LOW PRESSURE AREA
BEGINNING TO LIFT NORTHWARD ALONG THE GA/CAROLINA COAST. IN THE WAKE
OF THIS SYSTEM...LOW LEVEL WINDS WILL COME AROUND TO A MORE UNIFORM
WESTERLY DIRECTION. THE WEST WIND AND MOIST PROFILE SUGGEST A CHANCE
FOR SOME EARLY MORNING SHOWERS DEVELOPING OVER THE COASTAL WATERS
AND MOVING TOWARD SHORE.
A WESTERLY FLOW PATTERN IN TERMS OF CLIMO WOULD SHIFT THE BETTER
RAIN CHANCES INLAND FOR THE AFTERNOON IN A MORE DEFINED MANNER. WILL
FOLLOW THIS APPROACH FOR THE FORECAST GRIDS AND SHOW SHOWERS
SHIFTING INLAND FROM THE COAST DURING THE LATER MORNING AND EARLY
AFTERNOON HOURS AND THEN BECOMING MORE NUMEROUS EAST OF THE I-75
CORRIDOR.
A RETURN TO A MORE TYPICAL EARLY AUGUST PATTERN WILL ARRIVE FOR
TUESDAY INTO THE MIDDLE OF THE WEEK. READ MORE ABOUT THIS PATTERN
CHANGE IN THE LONG TERM DISCUSSION BELOW. ENJOY THE SECOND HALF OF
YOUR WEEKEND!
&&
.LONG TERM (TUESDAY THROUGH NEXT SATURDAY)...
THROUGH WED...AN UPPER TROUGH RESIDES ACROSS THE EASTERN CONUS WHILE
AN UPPER RIDGE EXTENDS FROM THE ATLANTIC ACROSS CUBA TO THE
CARRIBEAN SEA. AT THE SURFACE A TROUGH ACROSS SOUTH GA/NORTH FL AND
THE COASTAL WATERS LIFTS NORTHWARD ALONG THE EASTERN SEABOARD
WHILE THE NATIONAL HURRICANE CENTER MOVES BERTHA FROM EAST OF THE
BAHAMAS TO WELL SOUTHEAST OF NEW ENGLAND. A SURFACE RIDGE FROM THE
ATLANTIC ACROSS THE BAHAMAS TO THE SOUTHERN GULF TRACKS INTO SOUTH
FL. THE AREA CONTINUES IN A MOIST AND UNSTABLE AIRMASS WITH ISOLATED
TO HIGH END...50 POP...SCATTERED SHOWERS AND THUNDERSTORMS.
TEMPERATURES WILL RUN CLOSE TO NORMAL. THE SURFACE PRESSURE FIELD
WILL BE RELAXED WITH LIGHT WESTERLY FLOW ENHANCED BY AFTERNOON SEA
BREEZES.
FOR THU INTO SAT...THE EASTERN U.S. UPPER TROUGH LIFTS UP
NORTHEASTWARD AS IT SLIDES OUT OVER THE ATLANTIC WHILE THE CUBAN
RIDGE MOVES TO THE GULF AND FL. IN RESPONSE THE SURFACE RIDGE MOVES
INTO CENTRAL FL WITH THE LOW LEVEL FLOW GRADUALLY BECOMING MORE
SOUTHEASTERLY SOUTH OF THE RIDGE AXIS...BUT WITH A GRADIENT LIGHT
ENOUGH TO ALLOW AFTERNOON SEA BREEZES. NORTH OF THE THE AXIS THE
FLOW WILL BE SW TO WEST. THE ATMOSPHERE DRIES AND WARMS SLIGHTLY.
BUT STILL EXPECT SHOWERS AND STORMS IN THE LOW TO MID...30 TO 40
POPS...SCATTERED RANGE. TEMPERATURES WILL BE JUST ABOVE NORMAL.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS THE REGION EARLY THIS MORNING. LARGE
SWATH OF BKN-OVC HIGH LEVEL CIRRUS WILL SLOWLY SCATTER OUT THROUGH
SUNRISE TO THE SOUTH OF THE I-4 CORRIDOR. GENERAL VFR CONDITIONS
WILL REMAIN COMMON THROUGH THE DAY ON SUNDAY...HOWEVER SCATTERED TO
NUMEROUS SHOWERS AND STORMS WILL INITIATE DURING THE AFTERNOON. BEST
CHANCES TO SEE A STORM AND ASSOCIATED RESTRICTIONS WILL BE AT
KFMY/KRSW/KPGD AND KLAL. THE TERMINALS AROUND THE TAMPA BAY AREA MAY
STILL SEE A STORM...HOWEVER STORM COVERAGE SHOULD BE LESS INSIDE THE
I-75 CORRIDOR.
&&
.MARINE...
A WEAK AREA OF LOW PRESSURE WILL TRACK NORTHWARD TODAY AND TONIGHT
OVER THE FLORIDA PENINSULA BEFORE EXITING TO THE NORTHEAST DURING
MONDAY AND TUESDAY. IN THE WAKE OF THIS LOW HIGH PRESSURE WILL AGAIN
TAKE UP POSITION OVER THE CENTRAL AND EASTERN GULF OF MEXICO. WINDS
AND SEAS WILL BE LOW THE NEXT SEVERAL DAYS ALTHOUGH WIND DIRECTION
MAY BE A BIT ERRATIC THROUGH TONIGHT AS THE WEAK LOW MOVES NORTHWARD
THROUGH THE REGION.
&&
.FIRE WEATHER...
A MOIST LOW LEVEL ENVIRONMENT WILL KEEP RELATIVE HUMIDITY LEVELS WELL
ABOVE CRITICAL LEVELS THE NEXT SEVERAL DAYS. RAIN CHANCES WILL REMAIN
HIGH THROUGH MONDAY AND THEN SHOWERS AND STORM COVERAGE SHOULD RETURN
TO MORE NORMAL LEVELS FOR EARLY AUGUST BY THE MIDDLE PORTION OF THE
WEEK.
FOG POTENTIAL...SOME SHALLOW GROUND FOG MAY FORM OVER INLAND
LOCATIONS DURING THE EARLY MORNING HOURS THE NEXT FEW DAYS
BUT NO SIGNIFICANT VISIBILITY RESTRICTIONS ARE EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 91 77 91 78 / 50 40 40 40
FMY 92 77 91 76 / 70 40 50 40
GIF 93 77 92 76 / 60 40 60 30
SRQ 91 78 90 77 / 40 40 40 40
BKV 93 73 92 73 / 50 40 40 30
SPG 91 80 91 80 / 40 40 40 40
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/MARINE/AVIATION/FIRE WX...MROCZKA
LONG TERM...RUDE
AREA FORECAST DISCUSSION
NWS MIAMI FL
415 AM EDT SUN AUG 3 2014
.DISCUSSION...
DEEP MOISTURE HAS ARRIVED WITH 2"+ PWATS IN PLACE ACROSS SOUTH
FLORIDA ASSOCIATED WITH AN AREA OF LOW PRESSURE WHICH HAS BEEN
MOVING OUR WAY FROM THE BAHAMAS. FOR SEVERAL RUNS...MODELS HAVE BEEN
ADVERTISING NUMEROUS THUNDERSTORMS UNDERNEATH THIS SURFACE LOW
TODAY. MAY NEED TO BE WARY OF VERY SLOW MOVING STORMS AND STORM
COLLISIONS/MERGERS DUE TO LIGHT WINDS...LEADING TO POSSIBLE WATER
PROBLEMS OVER THE NEXT FEW DAYS. HRRR AND HI RES MODELS INDICATE
STORMS FIRST EITHER MOVE ONSHORE OR DEVELOP ALONG THE ATLANTIC
COAST...THEN CRAWL TO THE INTERIOR LATE DAY. THE WEAK LOW THEN
MOVES NORTH SUNDAY NIGHT AND MERGES WITH THE STATIONARY BOUNDARY
WHICH HAS BEEN DRAPED THROUGH THE SOUTHEAST FOR SEVERAL DAYS.
MODEL SOUNDINGS INDICATE THAT THE 2"+ PWATS REMAIN THROUGH
TUESDAY...ALTHOUGH THIS MAY BE SLIGHTLY OVERDONE CONSIDERING THE
MEAN RH IN SOME OF THE MODEL MASS FIELDS WHICH SHOWS A BIT OF A
DRYING TREND.
SURFACE WINDS WILL BECOME SW TO W MONDAY AND TUESDAY WITH THE
SURFACE LOW ACROSS NORTH FLORIDA. A MORNING GULF COAST IS EXPECTED
WITH FOCUS THEN SHIFTING TO THE INTERIOR AND ATLANTIC COAST LATER
IN THE DAY.
ALTHOUGH THE STATIONARY BOUNDARY WILL WASH OUT ACROSS THE
SOUTHEAST...A SUBTLE WEAKNESS/TROUGH WILL REMAIN ALONG THE EAST
COAST INTO THE MIDDLE OF NEXT WEEK. THIS WILL DELAY THE ARRIVAL OF
UPPER RIDGING/RISING HEIGHTS/SUBSIDENCE ACROSS SOUTH FLORIDA
UNTIL LATE NEXT WORK WEEK OR NEXT WEEKEND. THUS...WEDNESDAY MAY BE
A WETTER DAY THAN PREVIOUS FORECASTS HAVE SUGGESTED.
&&
.MARINE...
TROPICAL STORM BERTHA IS FORECAST TO REMAIN WELL EAST OF THE SOUTH
FLORIDA MARINE AREAS AS IT TURNS NORTH EAST OF THE BAHAMAS LATE
SUNDAY NIGHT THROUGH MONDAY. WINDS ARE FORECAST TO SHIFT TO THE
SOUTHWEST THROUGH THE EARLY PORTION OF THE WEEK FROM 5 KTS TO 15
KTS...THEN BECOMING VARIABLE AROUND 5 KTS BY THE END OF THE WEEK.
SCATTERED SHOWERS AND STORMS COULD LEAD TO GUSTY WINDS AND LOCALLY
CHOPPIER CONDITIONS EACH DAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 89 79 90 77 / 70 30 40 30
FORT LAUDERDALE 88 79 91 80 / 70 30 40 40
MIAMI 88 78 90 79 / 70 30 40 40
NAPLES 90 77 88 77 / 60 30 60 60
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...21/KM
LONG TERM....21/KM
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
343 AM CDT SUN AUG 3 2014
.DISCUSSION...
338 AM CDT
MAIN FORECAST CONCERNS/CHALLENGES ARE WITH RETURNING CHANCES FOR
WIDELY SCATTERED SHOWER/THUNDERSTORMS TODAY...AND THEN BETTER
CHANCES MONDAY AND MONDAY NIGHT.
GENERALLY CLEAR SKIES IN PLACE THIS MORNING AS A MID/UPPER LEVEL
RIDGE IS STILL IN PLACE...AND WITH SURFACE HIGH SETTLED OVERHEAD.
AS THIS RIDGE SLIDES TO THE SOUTHEAST TODAY...THE SURFACE HIGH
WILL LIKEWISE SLOWLY SHIFT EAST WITH A MORE FAVORABLE SETUP FOR
WEST/SOUTHWEST WINDS ACROSS THE CWA TODAY. AS HAS BEEN THE CASE
FOR THE LAST COUPLE OF DAYS...PLENTY SUNSHINE IN PLACE THIS
MORNING WILL HELP TO QUICKLY STEEPENING LOW LEVEL LAPSE RATES WITH
GUIDANCE INDICATING A WELL MIXED ENVIRONMENT BY MID/LATE MORNING.
INCREASING INSTABILITY WITHIN LOW 60S DEWPOINTS TODAY AS
APPROACHING SHORTWAVE ENERGY MOVES OVERHEAD COULD SUPPORT THE
DEVELOPMENT OF WIDELY SCATTERED THUNDERSTORMS AS EARLY AS MID DAY.
A MORE FAVORED LOCATION FOR THIS DEVELOPMENT WOULD BE ACROSS
NORTHERN ILLINOIS WHERE BETTER LARGE SCALE ASCENT WILL
RESIDE...ALTHOUGH STILL WEAK. DESPITE THESE MORE FAVORABLE
VARIABLES FOR SHOWER/THUNDERSTORM DEVELOPMENT...THERE WILL BE A
LACK OF ANY REAL GOOD SURFACE FOCUS TODAY WITH BETTER CHANCES
FOR PRECIP APPEARING TO BE ACROSS WISCONSIN. NONETHELESS...AT
LEAST ISOLATED BRIEF POP UP SHOWERS/THUNDERSTORMS STILL APPEAR
POSSIBLE AS WELL AS ISOLATED DEVELOPMENT ALONG LAKE BREEZE TODAY.
SO HAVE MAINTAINED SLIGHT CHANCE/CHANCE POPS THIS AFTERNOON...WITH
ONCE AGAIN BETTER CHANCES FURTHER NORTH NEAR THE
ILLINOIS/WISCONSIN BORDER. NOT OVERLY CONCERNED WITH ANY STRONGER
DEVELOPMENT TODAY...BUT BRIEF HEAVY DOWNPOUR AND GUSTY WINDS STILL
CANT BE COMPLETELY RULED OUT. DID INCREASE HIGH TEMPS FOR TODAY AS
LOW/MID 80S WITH EVEN SOME MID TO UPPER 80S DEFINITELY A
POSSIBILITY TODAY.
HAVE BACKED OFF ON POPS TONIGHT AS WHATEVER DEVELOPS THIS
AFTERNOON QUICKLY DIMINISHES EARLY THIS EVENING. FOCUS FOR
THUNDERSTORM DEVELOPMENT TONIGHT APPEAR TO REMAIN WELL WEST OF THE
CWA BACK TOWARDS IOWA AND MISSOURI WHERE INCREASING LLJ AND
SURFACE LOW/FRONTAL BOUNDARY WILL RESIDE...WITH A SEPARATE AREA OF
BETTER THUNDERSTORM DEVELOPMENT APPEARING TO BE WELL NORTH OVER
NORTHERN WISCONSIN ASSOCIATED WITH SOUTHWARD DROPPING COLD FRONT.
AS THIS COLD FRONT DROPS FURTHER SOUTH ON MONDAY...SURFACE
LOW/TROUGH TO THE WEST WILL BEGIN SHIFTING EAST TOWARDS THE CWA.
AS THESE FEATURES DRAW CLOSER TO THE CWA LATER IN THE DAY
MONDAY...SHOWER/THUNDERSTORM CHANCES WILL INCREASE ESPECIALLY
OVER NORTHERN ILLINOIS. DID INCREASE POPS OVER THIS AREA TO HIGH
CHANCE POPS AND BROUGHT AT LEAST A SLIGHT CHANCE FOR THUNDERSTORMS
FOR THE REMAINING CWA BY THE AFTERNOON TIME FRAME AS FAVORABLE
INSTABILITY IN PLACE WHILE SEVERAL WAVES OF ENERGY MOVE OVERHEAD
COULD PROVIDE SOME OUTSIDE SCATTERED DEVELOPMENT. NOT CONCERNED
WITH ANY SEVERE THREAT AT THIS TIME...AS BEST THUNDERSTORM
DEVELOPMENT SHOULD REMAIN TIED CLOSER TO THE LOW/TROUGH AND BETTER
INSTABILITY TO THE WEST DURING MOST OF THE DAY.
BEST CHANCES SHOWERS/THUNDERSTORMS DURING THIS PERIOD WILL BE
MONDAY NIGHT AS SURFACE LOW/TROUGH AND FRONTAL BOUNDARY PUSH
THROUGH. INCREASING MOISTURE COULD SUPPORT HEAVY DOWNPOURS WITH
CONFIDENCE REMAINING LOW ON THE STRENGTH OF THIS CONVECTION. WEAK
AND UNFAVORABLE DIRECTED LLJ AND LOWER INSTABILITY SHOULD HELP TO
LIMIT STRENGTH...BUT COULD STILL SEE AT LEAST SOME ISOLATED
STRONGER STORMS STILL DEVELOPING.
RODRIGUEZ
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* SMALL CHANCE OF ISOLATED AFTERNOON TSRA.
* WIND SHIFT TO EAST POSSIBLE WITH LAKE BREEZE LATE THIS
AFTERNOON.
RATZER
//DISCUSSION...UPDATED 06Z...
CALM OR LIGHT/VARIABLE WINDS ARE EXPECTED TO BECOME WEST-
SOUTHWEST AFTER SUNRISE THIS MORNING. GRADIENT REMAINS WEAK ENOUGH
THAT A LAKE BREEZE WILL LIKELY DEVELOP...THOUGH HOW FAR INLAND IT
MOVES IS UNCERTAIN. MOST HIGH-RES GUIDANCE KEEPS THE BOUNDARY EAST
OR ORD/MDW THROUGH THE AFTERNOON AND HAVE ELECTED TO KEEP WIND
SHIFT OUT OF TAFS AT THIS POINT EXCEPT AT GYY.
POTENTIAL FOR ISOLATED TSRA RETURNS TODAY AS UPPER TROUGH MOVES
OVER REGION. FORECAST SOUNDINGS DEPICT UNSTABLE THERMODYNAMIC
PROFILES WITH LITTLE/NO CAP BY EARLY AFTERNOON. WEAK WINDS AND
LACK OF ORGANIZED CONVERGENCE ARE THE ONLY LIMITS TO DEVELOPMENT
OF SOME TSRA...AND LAKE BREEZE BOUNDARY COULD FOCUS FOR
DEVELOPMENT ESPECIALLY NORTH TOWARD WI WHERE INSTABILITY WILL BE
GREATER. HAVE MAINTAINED PROB30 MENTION AT ORD AND ADDED SAME AT
RFD WHERE POTENTIAL...WHILE STILL LOW...WILL BE A LITTLE HIGHER
THAN AREAS FARTHER SOUTH/SOUTHEAST. IF DEVELOPMENT DOES OCCUR
HOWEVER...TSRA WILL LIKELY SPREAD ALONG OUTFLOW BOUNDARIES OR LAKE
BREEZE IF IT DEVELOPS.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* LOW CONFIDENCE IN TSRA COVERAGE THIS AFTERNOON.
* LOW CONFIDENCE IN LAKE BREEZE PASSAGE/WIND SHIFT TO EAST THIS
AFTERNOON.
RATZER
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY AND TUESDAY...SLIGHT CHANCE OF TSRA BUT MAINLY VFR.
WEDNESDAY THROUGH FRIDAY...PREDOMINANTLY VFR.
IZZI
&&
.MARINE...
231 AM CDT
A PERIOD OF QUIET WEATHER LOOKS TO CONTINUE ACROSS LAKE MICHIGAN
THROUGH THE PERIOD...WITH HIGH PRESSURE DOMINATING THE SURFACE
PATTERN ACROSS THE WESTERN LAKES REGION. A WEAK LOW MOVING FROM
NORTHEASTERN ONTARIO INTO QUEBEC TODAY AND TONIGHT WILL TRAIL A WEAK
COLD FRONT ACROSS LAKE MICHIGAN THIS AFTERNOON THROUGH MONDAY. HIGH
PRESSURE WILL THEN BUILD IN BEHIND THE FRONT AGAIN TUESDAY...WITH A
PERIOD OF NORTHERLY WINDS WHICH MAY STRENGTHEN INTO THE 15-20 KT
RANGE FOR A TIME TUESDAY INTO TUESDAY EVENING. THE HIGH WILL THEN
TAKE UP RESIDENCE ACROSS THE REGION DURING THE MIDDLE AND END OF THE
WEEK WITH LIGHTER WINDS AND DAILY LAKE BREEZES.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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[top]
Area Forecast Discussion
National Weather Service Lincoln IL
245 AM CDT Sun Aug 3 2014
.DISCUSSION...
ISSUED 245 AM CDT Sun Aug 3 2014
SHORT TERM...Today through Tuesday
Another pleasant summer day is on tap across central Illinois
today, as 1020mb high centered over the region remains in control
of the weather. A short-wave trough currently evident on 07z/2am
water vapor imagery over southwest Iowa will track southeastward,
but will remain W/SW of the KILX CWA. Small cluster of showers/storms
associated with this feature will drop into northern Missouri over
the next few hours, then will gradually dissipate later this
morning as it pushes toward the ridge axis. Am therefore expecting
mostly sunny and dry conditions today with highs in the middle
80s.
A series of upper-level waves is expected to reinforce the mean
trough over eastern Canada and the Great Lakes over the next
couple of days, with the first wave pushing a cold front southward
toward central Illinois by late Monday. Models in relatively good
agreement that boundary will sag into the northern KILX CWA by 12z
Tue accompanied by scattered showers/thunder. Models have trended
slightly faster with the approach of the front, with both the NAM
and GFS now bringing precip into the W/NW as early as Monday
afternoon. Have therefore added low chance PoPs from the Peoria
area northward late in the day. Better rain chances arrive Monday
night into Tuesday as front approaches and gradually stalls across
the area.
LONG TERM...Wednesday through Saturday
Main forecast concern in the extended is how far south front will
get pushed as additional short-wave energy deepens the Great Lakes
trough later in the week. Both the 12z Aug 2 and 00z Aug 3 runs of
the GFS featured a prominent surface high building southward into
the Great Lakes, pushing the cold front south of the Ohio River by
Thursday. This solution would bring an end to the rain chances as
a slightly cooler/drier airmass arrives during the Thursday
through Saturday time frame. Meanwhile the 12z ECMWF offered a
much different solution showing a weaker high which subsequently
kept the boundary further north across central Illinois. 00z run
of the ECMWF has changed its tune completely and now looks a lot
more like the GFS. As a result, have begun to trim PoPs from north
to south later in the week as confidence is growing that front
will drop south of the area by Thursday. At this time, will
maintain low chance PoPs for both Thursday/Friday, but these will
likely be removed completely with later forecasts as better model
consistency is achieved.
Barnes
&&
.AVIATION...
ISSUED 1139 PM CDT Sat Aug 2 2014
Forecast concern focused on potential for light fog the rest of
tonight. Moisture levels a bit higher than last night, with dew
points expected to remain at or above 60 degrees over most of the
area. Latest HRRR guidance indicates the best shot for lower
visibilities in fog would be near KSPI, and this area also was
affected earlier Saturday morning. Will hit that area a little
harder than the other TAF sites with a TEMPO group of around 1SM,
with 2-3SM elsewhere. Beyond that, VFR conditions to prevail. Any
ceilings that form later Sunday afternoon and evening will likely
be at or above 6000 feet.
Geelhart
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1258 AM CDT SUN AUG 3 2014
.DISCUSSION...
156 PM CDT
TONIGHT...
SFC RIDGE REMAINS OVERHEAD THIS AFTERNOON...WHICH HAS LIMITED THE
COVERAGE OF CLOUDS AND CONTINUES TO PROVIDE MINIMAL WIND FOR THE
CWFA. A LAKE BREEZE WAS TRYING TO FORM ALONG THE SHORELINE...AND
WILL LIKELY BECOME MORE NOTICEABLE LATER THIS AFTERNOON AS THE
INLAND AREAS WARM INTO THE LOW 80S. MEANWHILE ALONG THE IMMEDIATE
LAKESHORE...LAND SITES WILL LIKELY REMAIN IN THE LOWER/MIDDLE 70S
THIS AFTERNOON. LLVL MOISTURE HAS ALSO BEEN MORE PLEASANT...WITH DEW
POINTS HOVERING AROUND 60 AND PWAT VALUES LESS THAN 1". GUIDANCE
CONTINUES TO SUGGEST THIS AFTN WILL REMAIN DRY...AND LATEST LOCAL
ARW8KM HAS INDICATED EVEN LESS CLOUDS DEVELOPING UNDERNEATH THE SFC
RIDGE.
SFC RIDGE REMAINS OVERHEAD THRU THIS EVENING/OVERNIGHT...WHICH SHUD
ALLOW FOR A DRY PERIOD.
CONFIDENCE...HIGH.
SUNDAY THROUGH MON NGT...
A MID-LVL WAVE OVER THE CENTRAL/NORTHERN PLAINS WILL STEADILY SLIDE
EAST AND SHUD ARRIVE OVER THE FORECAST AREA CLOSER TO DAYBREAK SUN.
THE SFC WAVE WILL BE DRIFTING EAST...ALLOWING THE FLOW TO TURN
SOUTHERLY TO SOUTHWESTERLY. A CHANNEL OF INCREASED LLVL MOISTURE
WILL LAYOUT FROM NORTHERN MISSOURI STRETCHING NORTHEAST THROUGH THE
NORTHERN CWFA INTO NORTHERN LAKE MICHIGAN. THE COMBINATION OF AN
APPROACHING WEAK WAVE AND INCREASED LLVL MOISTURE...ALL POINTS
TOWARDS SOME PRECIP/STORMS POSSIBLE LATE SUN MORNING THRU AFTN.
ALTHOUGH THAT BEING SAID...GUIDANCE SUGGESTS THE WAVE WILL BE IN A
WEAKENING PHASE AS IT ARRIVES AND THE LACK OF FORCING SEEMS TO
SUGGEST THAT ANY CONVECTION THAT DEVELOPS WILL BE ISOLATED AND
LIKELY CONFINED TO AREAS ALONG AND NORTH OF I-80 IN NORTHERN IL.
MID-LVL TROUGH REMAINS OVER THE EASTERN GREAT LAKES...WHICH SHUD
KEEP OUR FORECAST AREA GENERALLY IN A WEAK NORTHWEST FLOW THRU MON.
SOLUTIONS CONTINUE TO POINT TOWARDS A SERIES OF WEAK WAVES SLIDING
SOUTHEAST WHICH COULD CONTINUE THE LOW POPS SUN NGT THRU MON NGT.
HAVE HELD ONTO A DRY FORECAST FOR THE FAR SOUTHERN CWFA THROUGH MON.
MON EVE THE LOCAL ARW8KM IS INDICATING A SLIGHTLY STRONGER WAVE
ARRIVING LATE MON EVE...THUS HAVE NUDGED POPS UP FOR THE ENTIRE
AREA.
TEMPS BOTH SUN/MON WILL GENERALLY BE SEASONAL...IN THE LOW 80S.
HUMIDITY WILL BE SLIGHTLY HIGHER WITH DEW POINTS IN THE LOW
60S...NEARING THE MID/UPR 60S MON NGT.
TUESDAY...MON NGT A BROAD SFC RIDGE OVER THE CANADIAN PRAIRIES WILL
DRIFT SOUTHEAST...WITH A STALLED FRONTAL BOUNDARY OVER THE FORECAST
AREA THRU TUE. GUIDANCE HAS BEEN LEANING TOWARDS THIS FEATURE BEING
FOCUSED OVER THE CENTRAL CWFA TUE...WHICH WOULD ALLOW FOR A COOLER
NORTHEAST FLOW ACROSS THE NORTHERN CWFA. MEANWHILE THE SOUTHERN CWFA
WILL STILL BE IN THE LOW 80S. STILL LOOKS FAVORABLE FOR CONVECTIVE
CHANCES TUE...SO HAVE HELD ONTO THE CHC POPS.
TROUGH AXIS PIVOTS OVERHEAD TUE EVE...WITH BROAD SFC RIDGE PROGGED
IT IS POSSIBLE DRY CONDS COULD DEVELOP TUE NGT. UNFORTUNATELY WITH
THE LACK OF A STRONG PUSH TO MOVE THE STALLED FRONTAL BOUNDARY
FURTHER SOUTH...AND A DEVELOPING WAVE OVER THE COLORADO FRONT-RANGE
TUE EVE...FEEL HOLDING ONTO LOW CHC POPS AT THIS TIME LOOKS
APPROPRIATE.
CONFIDENCE...MEDIUM.
WEDNESDAY THROUGH SATURDAY...
NORTH ATLANTIC RIDGE WILL BE WEAKENING...ALLOWING THE BLOCKED FLOW
OVER THE CONUS TO BECOME A LITTLE MORE FLUID. HIGH AMPLITUDE RIDGE
ACROSS THE ROCKIES WILL START TO FLATTEN WITH TIME...WHICH SHOULD
ALLOW FOR A SEMI-ZONAL PATTERN FOR THE SECOND HALF OF NEXT WEEK.
CURRENT GFS/EC SOLUTIONS HAVE COME INTO BETTER AGREEMENT THAT WEAK
MID-LVL RIDGING WILL PUSH OVERHEAD WED/THUR WITH SFC RIDGE...AND
COULD PRODUCE A FEW DRY PERIODS NEXT WEEK. BEYOND THUR THOUGH
GUIDANCE STARTS TO DIFFER WITH ENSEMBLES STILL SHOWING CONSIDERABLE
SPREAD IN THE NEAR SFC FIELDS. LONGWAVE PATTERN STILL IS SUGGESTIVE
OF A TROUGH DEVELOPING OVER THE MID-ATLANTIC AND COULD HELP TO KEEP
THE GREAT LAKES IN A SEMI-FLAT FLOW TRENDING NORTHWEST.
TEMPS COULD PUSH BACK BELOW SEASONAL CONDS FOR THE START OF THE
EXTENDED...BUT SHUD THEN RETURN TO THE LOW 80S. THEN AS NOTED
EARLIER...PERIODIC CHANCES FOR SHOWERS AND THUNDERSTORMS WITH THE
GREATEST POSSIBILITY BEING THE FAR WEST/SOUTH CWFA AS A PARKED
FRONTAL BOUNDARY WILL BE ORIENTED FROM THE CENTRAL PLAINS SOUTHEAST
THROUGH THE TENN VALLEY.
CONFIDENCE...MEDIUM.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* SMALL CHANCE OF ISOLATED AFTERNOON TSRA.
* WIND SHIFT TO EAST POSSIBLE WITH LAKE BREEZE LATE THIS
AFTERNOON.
RATZER
//DISCUSSION...UPDATED 06Z...
CALM OR LIGHT/VARIABLE WINDS ARE EXPECTED TO BECOME WEST-
SOUTHWEST AFTER SUNRISE THIS MORNING. GRADIENT REMAINS WEAK ENOUGH
THAT A LAKE BREEZE WILL LIKELY DEVELOP...THOUGH HOW FAR INLAND IT
MOVES IS UNCERTAIN. MOST HIGH-RES GUIDANCE KEEPS THE BOUNDARY EAST
OR ORD/MDW THROUGH THE AFTERNOON AND HAVE ELECTED TO KEEP WIND
SHIFT OUT OF TAFS AT THIS POINT EXCEPT AT GYY.
POTENTIAL FOR ISOLATED TSRA RETURNS TODAY AS UPPER TROUGH MOVES
OVER REGION. FORECAST SOUNDINGS DEPICT UNSTABLE THERMODYNAMIC
PROFILES WITH LITTLE/NO CAP BY EARLY AFTERNOON. WEAK WINDS AND
LACK OF ORGANIZED CONVERGENCE ARE THE ONLY LIMITS TO DEVELOPMENT
OF SOME TSRA...AND LAKE BREEZE BOUNDARY COULD FOCUS FOR
DEVELOPMENT ESPECIALLY NORTH TOWARD WI WHERE INSTABILITY WILL BE
GREATER. HAVE MAINTAINED PROB30 MENTION AT ORD AND ADDED SAME AT
RFD WHERE POTENTIAL...WHILE STILL LOW...WILL BE A LITTLE HIGHER
THAN AREAS FARTHER SOUTH/SOUTHEAST. IF DEVELOPMENT DOES OCCUR
HOWEVER...TSRA WILL LIKELY SPREAD ALONG OUTFLOW BOUNDARIES OR LAKE
BREEZE IF IT DEVELOPS.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* LOW CONFIDENCE IN TSRA COVERAGE THIS AFTERNOON.
* LOW CONFIDENCE IN LAKE BREEZE PASSAGE/WIND SHIFT TO EAST THIS
AFTERNOON.
RATZER
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY AND TUESDAY...SLIGHT CHANCE OF TSRA BUT MAINLY VFR.
WEDNESDAY THROUGH FRIDAY...PREDOMINANTLY VFR.
IZZI
&&
.MARINE...
228 PM CDT
NO MAJOR CONCERNS OVER THE LAKE FOR THE COMING DAYS. HIGH PRESSURE
REMAINS IN CONTROL THIS AFTERNOON AND EVENING. WEAK LOW PRESSURE
WILL GLIDE THROUGH THE NORTHERN LAKES AND SOUTHERN ONTARIO THE
NEXT FEW DAYS. THE MAIN IMPACT WILL BE TO INCREASE THE GRADIENT
ACROSS THE LAKE ON SUNDAY THOUGH SOUTHERLY WINDS REMAIN 15 KT OR
LESS. AS THESE WEAK SYSTEMS PASS TO THE EAST...HIGH PRESSURE
BUILDS OVER LAKE SUPERIOR AND WILL PUSH A WEAK COLD FRONT THROUGH
THE NORTHERN HALF OF THE LAKE BEFORE DISSIPATING WITH A SWITCH
BACK TO MORE OF A NORTHERLY WIND PATTERN ON MONDAY.
MEANWHILE...LOW PRESSURE WILL ORGANIZE IN THE PLAINS BUT WILL BE
SLOW TO APPROACH THE AREA. A FEW WEAK SURFACE LOWS MAY PASS BY
WELL TO THE SOUTH MAINTAINING A NORTH TO NORTHEAST FLOW THROUGH
MID TO LATE WEEK. KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1139 PM CDT Sat Aug 2 2014
.DISCUSSION...
ISSUED 837 PM CDT Sat Aug 2 2014
High pressure axis extending southwest from lower Michigan into
northern Missouri early this evening. Diurnal cumulus has faded
and we may see a few high clouds move in overnight, but mostly
clear skies to prevail. Temperatures still on track to fall into
the upper 50s and lower 60s overnight. Sent an update earlier to
adjust the sky grids, but no changes needed to the worded
forecasts.
Geelhart
&&
.AVIATION...
ISSUED 1139 PM CDT Sat Aug 2 2014
Forecast concern focused on potential for light fog the rest of
tonight. Moisture levels a bit higher than last night, with dew
points expected to remain at or above 60 degrees over most of the
area. Latest HRRR guidance indicates the best shot for lower
visibilities in fog would be near KSPI, and this area also was
affected earlier Saturday morning. Will hit that area a little
harder than the other TAF sites with a TEMPO group of around 1SM,
with 2-3SM elsewhere. Beyond that, VFR conditions to prevail. Any
ceilings that form later Sunday afternoon and evening will likely
be at or above 6000 feet.
Geelhart
&&
.PREV DISCUSSION...
ISSUED 148 PM CDT Sat Aug 2 2014
Models in general agreement with overall evolution of upper trough
over the Great Lakes and the Midwest gradually beginning to shift
east of the region by late next week. However, individual wave
timing and strength have a significant bearing on the forecast and
leads to increased uncertainty.
SHORT TERM...Tonight through Monday
Cumulus are suppressed under high pressure this afternoon though
boundary layer moisture remains in place with dew points similar
to what was in place in dry areas at this time yesterday. The
combination of the trapped low-level moisture, clear skies, and
light winds will likely lead to some patchy fog again late tonight.
12z NAM moves some precip into northern forecast area Sunday and
even more so on Monday. Although there will be waves rotating
through the long wave trough over eastern Canada, question is how
much moisture will interact with the energy. Stability remains
relatively limited per forecast soundings with warming mid-levels
and slowly building 500mb heights. There is also not a clear
indication of surface boundaries to focus convergence. Wouldn`t
completely rule out convection at some point Sunday and/or Monday
afternoon, but coverage should remain isolated and will leave PoPs
below slight chance category for now.
LONG TERM...Monday Night through Saturday
Heights begin to fall again Monday Night and Tuesday as final vort
max rotates around eastern trough and pushes its surface
reflection in the form of a cold front. The front should provide a
focus for the development of thunderstorms. Deep moisture should
remain limited as the Gulf remains cutoff. Evapotranspiration
should provide enough for scattered storms, but widespread precip
will likely need to wait until southerly moisture advection sets
up Wednesday Night and Thursday.
Big model differences focus on how far south the cold front can
push before the flow weakens and moisture becomes available. GFS
is strongest with the push behind the front with overrunning
precip behind the front clearing central and southeast Illinois
Thursday and Thursday Night. The ECMWF is much weaker with the
upper energy and stalls the front over the southern half of
Illinois from Tuesday through Friday bringing periodic chances
for MCS development along and north of the front. The 12z ECMWF
will be favored as it is more consistent with the 00z suite. Will
therefore keep more clouds and PoPs in place across the area than
would be suggested by the GFS with rain chances persisting through
the weak with the axis of the higher QPF slowly shifting south
with time. It is likely that much more detail as to timing and
track can be added as the period approaches.
Model temperatures also vary significantly given the differences
in frontal position. The GFS being further south with the cold
front is 2-4C colder than the ECMWF at 850 mb through the end of
the week. Will go closer to the smaller diurnal range and overall
warmer solution of the ECMWF.
Barker
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS JACKSON KY
118 AM EDT SUN AUG 3 2014
.UPDATE...
ISSUED AT 118 AM EDT SUN AUG 3 2014
UPDATED THE FORECAST TO ADD A DENSE FOG ADVISORY FOR MUCH OF EASTERN
KENTUCKY. THE FOG SHOULD BEGIN TO LIFT BETWEEN 9 AND 10 AM.
UPDATE ISSUED AT 1110 PM EDT SAT AUG 2 2014
FOG HAS DEVELOPED AND INTENSIFIED EARLY THIS EVENING...AND IS
BECOMING MORE WIDESPREAD ACROSS THE NORTHEASTERN TWO THIRDS OF THE
CWA. BEEFED UP THE FOG IN THE GRIDS AND ZONES FOR THE REMAINDER OF
THE OVERNIGHT PERIOD. AS WE ARE HEADING INTO SUNDAY...IMPACT SHOULD
BE RELATIVELY LOW AS FOG SHOULD HAVE BEGUN TO LIFT BY THE TIME CHURCH
GOERS GET OUT. ALSO AM NOT CONVINCED FOG WILL BE WIDESPREAD ENOUGH
TO WARRANT HEADLINES. HIT THE FOG HARDEST ALONG AND NORTHEAST OF A
IRVINE TO MANCHESTER TO WHITESBURG LINE...WHERE LOCATIONS MOST LIKELY
SAW EVENING CONVECTION AND RAINFALL. ISSUED A SPECIAL WEATHER
STATEMENT TO HIGHLIGHT FOG FOR THESE AREAS. FURTHER SOUTHWEST WHERE
LESS RAIN WAS EVIDENT WENT WITH PATCHY DENSE WORDING IN THE ZONES AND
GRIDS. ALSO TWEAKED GRIDS FOR HOURLY TRENDS. NO OTHER CHANGES TO THE
FORECAST PACKAGE ATTM.
UPDATE ISSUED AT 827 PM EDT SAT AUG 2 2014
CONVECTIVE ACTIVITY IS DISSIPATING AT A RAPID PACE THIS EVENING AS
AIR MASS IN PLACE STABILIZES. WILL REMOVE ALL MENTION OF THUNDER
WITH NEXT UPDATE...AND POSSIBLY ALL POPS. FOG WILL LIKELY FORM
THROUGH THE OVERNIGHT PERIOD. POTENTIAL IS ADDRESSED WELL IN THE
PRESENT FORECAST. OTHERWISE BROUGHT GRIDS IN LINE WITH HOURLY OBS AND
FRESHENED UP ZONE WORDING.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 301 PM EDT SAT AUG 2 2014
THE HRRR MODEL SEEMED TO HAVE THE BEST HANDLE ON THE SHOWER AND STORM
ACTIVITY THAT HAS BEEN ONGOING ACROSS EASTERN KENTUCKY FOR THE PAST
FEW HOURS. THEREFORE...THE HRRR SOLUTION WAS USED TO CREATE THE NEW
FORECAST PRECIPITATION PROBABILITIES FOR THE AREA FOR THE REST OF
THIS AFTERNOON THROUGH 2Z THIS EVENING. AFTER 2Z TONIGHT...THE NAM12
MODEL WAS USED. SHOWERS AND STORMS ARE EXPECTED TO PERSIST THROUGH
ROUGHLY 2Z THIS EVENING...WITH THE PEAK ACTIVITY OCCURRING DURING
PEAK HEATING HOURS THIS AFTERNOON. A SHORTWAVE TROUGH INTERACTING
WITH LIMITED LOW LEVEL MOISTURE IS THE DRIVING FORCE FOR
PRECIPITATION THIS AFTERNOON...AND WILL BE UNTIL THE TROUGH MOVES
EAST OF THE AREA EARLY THIS EVENING. SOME OF THE STORMS THIS
AFTERNOON HAVE BEEN A BIT STRONG AND CAPABLE OF PRODUCING SMALL
HAIL...LOCALLY HEAVY RAINFALL...AND WIND GUSTS UP TO 30 MPH. AFTER
THIS EVENING...HIGH PRESSURE WILL SETTLE OVER THE AREA...ALLOWING FOR
A DRIER AND SLIGHTLY WARMER PATTERN. HIGHS ON SUNDAY ARE EXPECTED TO
RISE INTO THE LOW TO MID 80S UNDER AMPLE SUNSHINE AND LIGHT WINDS.
LOWS THE NEXT COUPLE OF NIGHTS WILL BOTTOM OUT AROUND 60...WHICH IS
A BIT BELOW NORMAL FOR THIS TIME OF YEAR. THE WEATHER RELATED ISSUED
TO LOOK OVERNIGHT WILL BE FOG FORMATION. FOG WILL BE POSSIBLE IN OUR
RIVER VALLEYS OVERNIGHT. THE MAIN QUESTION WILL BE THE EXTENT AND
DENSITY OF FOG THAT FORMS WHERE PRECIPITATION HAS ALREADY OCCURRED
TODAY. THE OTHER FACTOR INVOLVED WITH THE FOG WILL BE THE AMOUNT OF
CLOUD COVER THAT PERSISTS OVERNIGHT. IF THE CLOUDS CLEAR OUT MORE
QUICKLY THEN FOG FORMATION WILL BE FAVORED...PARTICULARLY FOR
LOCATIONS WHERE IT RAINED TODAY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 403 PM EDT SAT AUG 2 2014
THE MODELS REMAIN IN DECENT AGREEMENT WITH THE LONG WAVE PATTERN
THROUGH NEXT WEEKEND. OVERALL...THE FLOW LOOKS TO FLATTEN OUT ACROSS
THE MISSISSIPPI VALLEY...WITH THE DEEPER AND PERSISTENT TROUGHING
BECOMING MORE CONFINED TO THE NORTHEASTERN CONUS.
FOR EASTERN KENTUCKY...DRY WEATHER WILL HANG IN THROUGH
TUESDAY...BEFORE A COLD FRONT SAGS SOUTHEAST AND EVENTUALLY STALLS
ACROSS OUR VICINITY. DAILY CHANCES OF SCATTERED SHOWERS AND
THUNDERSTORMS WILL REIGN FROM TUESDAY NIGHT THROUGH NEXT WEEKEND.
STAYED CLOSE TO THE BLENDED GUIDANCE...ALTHOUGH DID UNDERCUT A BIT IN
THE POPS FURTHER OUT GIVEN THE LOW CONFIDENCE IN TRYING TO NAIL DOWN
SMALLER SCALE FEATURES. TEMPERATURES WILL AVERAGE NEAR NORMAL THROUGH
THE PERIOD AS WELL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 118 AM EDT SUN AUG 3 2014
THERE IS A DENSE FOG ADVISORY OUT FOR MUCH OF EASTERN KENTUCKY FOR
THE NORTHEASTERN TWO THIRDS OF THE AREA. IN THOSE AREA...THE FOG IS
IN THE VALLEYS AND WELL AS ON SOME OF THE RIDGES. THE REST OF EASTERN
KENTUCKY HAS OR WILL HAVE AREAS FOG OF DENSE FOG IN THE VALLEYS. THIS
LOOKS LIKE ONE OF THOSE DAYS WHERE THE FOG WILL CONTINUE THICKEN AND
EVENTUALLY MOVE INTO THE TAF STATIONS. THE MODEL GUIDANCE IS SPLIT
AND THE GFS MOS IS MORE OPTIMISTIC THAN THE NAM AND THE LAMP
GUIDANCE. WILL HAVE SOME TEMPO VLIFR IN ALL OF THE TAF STATIONS. SJS
IS THE MOST LIKELY TO HAVE THE WORST CONDITIONS. ONCE THE FOG BURNS
OFF BETWEEN 13-14Z...THE REST OF THE PERIOD WILL BE VFR.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR KYZ044-
050>052-058>060-104-106>120.
&&
$$
UPDATE...JJ
SHORT TERM...AR
LONG TERM...GEOGERIAN
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
346 AM CDT SUN AUG 3 2014
.SHORT TERM...
THE OLD STATIONARY FRONT AND A BROAD LOW PRESSURE SYSTEM REMAIN IN
PLACE TODAY. OVERNIGHT PRECIPITATION WAS ASSOCIATED WITH THE LOW
PRESSURE SYSTEM. WITH THESE SMALL SCALE FEATURES AND A PWAT OF
NEARLY 2 INCHES... SOME SHOWERS AND EVEN AN ISOLATED THUNDERSTORM
ARE POSSIBLE AGAIN TODAY. RUC MEAN RH FROM H10 TO H5 HAS 85
PERCENT JUST OFFSHORE FOR THIS MORNING. EVEN WITH ALL THESE
FACTORS...LOWERED THE POPS SOME FOR TODAY WITH THE RATIONAL THAT
OFTEN A WEAKNESS AREA AWAY FROM THE SFC LOW ACTS TO DAMPEN RAIN
CHANCES AS WE SAW THE LAST FEW DAYS OVER THE EASTERN PART OF OUR
FORECAST AREA PER THE STP 8BIT DATA FROM THE WSR88D. MOST OF RAIN
TODAY AND TOMORROW WILL BE INFLUENCED NEAR AND AROUND THE LOW.
NEVERTHELESS... SOME SHOWERS AND AN ISOLATED THUNDERSTORM WILL
STILL BE POSSIBLE. AREAS THAT DO RECEIVE RAIN CAN EXPECT THESE
SLOW MOVING STORMS TO PRODUCE SOME HEAVY RAIN AND FREQUENT
LIGHTNING. KEG
.LONG TERM...
AS THESE OLD BOUNDARIES GRADUALLY WASH OUT... WE WILL SEE A RETURN
TO A NORMAL SUMMER REGIME WITH AFTERNOON THUNDERSTORMS ALONG SEA
BREEZE FRONTS..BUT OVERALL DRIER. THE EAST COAST TROUGH WILL
CONTINUE TO DOMINATE AND EVENTUALLY RELEASE SOME OF ITS GRIP ON
THE SE US BY THE END OF THE WEEK AS HIGH PRESSURE BUILDS OVER THE
DESERT SW AND THE BERMUDA HIGH TRIES TO NUDGE WESTWARD. KEG
&&
.AVIATION...
SOME PATCHY MVFR IN LIGHT RADIATIONAL FOG AT A FEW LOCATIONS THIS
MORNING. OTHERWISE VFR CONDITIONS TO PREVAIL DURING THE DAY AND
EVENING OUTSIDE LIMITED CONVECTION AREAS. DOWNBURST GUST POTENTIAL
25-30 KT TODAY. PATCHY SHALLOW RADIATIONAL FOG MAY ONCE AGAIN
DEVELOP OVERNIGHT IN AREAS THAT MAY BE AFFECTED BY RAINFALL TODAY.
24/RR
&&
.MARINE...
BENIGN WINDS AND SEAS ARE EXPECTED TO PREVAIL NEXT 5 DAYS AS WEAK
HIGH PRESSURE STAYS PARKED OVER THE NORTH GULF. THE GULF-LAND BREEZE
CYCLE APPEARS TO BE PERTURBED BY LARGER SCALE FEATURES BUT NOCTURNAL
CONVECTION IS STILL POSSIBLE EACH NIGHT FOCUSED ON SUBTLE
CONVERGENCE BOUNDARIES...AS IS CURRENTLY THE CASE OVER AND SOUTH OF
THE ATCHAFALAYA BAY. 24/RR
&&
.DECISION SUPPORT...
DSS CODE...GREEN.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TO HIGH RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE.
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 85 71 87 71 / 40 20 30 20
BTR 88 72 89 72 / 40 20 30 20
ASD 89 72 88 72 / 40 30 40 20
MSY 89 76 89 76 / 40 30 30 20
GPT 91 76 91 77 / 40 30 30 20
PQL 87 71 88 72 / 40 30 30 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
300 AM EDT SUN AUG 3 2014
.SYNOPSIS...
A FRONTAL BOUNDARY REMAINS NEARLY STATIONARY ALONG THE MID ATLANTIC
COAST THROUGH MONDAY. AREAS OF LOW PRESSURE WILL TRACK NORTHEAST
ALONG THIS BOUNDARY...KEEPING UNSETTLED CONDITIONS IN PLACE INTO
EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
LATEST ANALYSIS SHOWING SFC TROUGH PERSISTING ALONG THE COASTAL
AREAS WITH WEAK HIGH PRESSURE CENTERED OFF NEW ENGLAND NOSING SSW
INTO THE MID ATLC. THIS IN SITU CAD SETUP MAKING FOR AN
ANOMALOUSLY COOL EARLY AUGUST WX ACRS THE REGION...TEMPERATURES
TDA GENLY NO BETTER THAN THE 70S.
WILL HAVE HI PROB FOR SHRAS OVRNGT ERN PORTION (60-80%)...NOT
RULING OUT LOCALLY HEAVY RA...BUT THAT APPEARS TO BE A LO PROB
ATTM (UNLESS PAST COUPLE RUC RUNS TURNS OUT RIGHT W/
DEVELOPING/MOVING AREA OF MDT/HEAVY RA NE NR THE CST OVRNGT).
HANGING ONTO 20% W. LO TEMPS FM THE M60S TO ARND 70F.
MAIN CONCERN OVER THE NEXT 24 HRS CONTINUES TO BE HEAVY
RAINFALL...AND ACRS MOST OF SE VA/NE NC PRECIP AMOUNTS HAVE
AVERAGED 2-3" WITH LOCAL AMOUNTS OVER 4" RECEIVED. WHILE PRECIP
THUS FAR TODAY HAS BEEN SOMEWHAT SPOTTY AND SPORADIC...THINK THERE
ARE ENOUGH ATMOSPHERIC INGREDIENTS IN PLACE LATER TONIGHT TO
JUSTIFY A FLOOD WATCH. PER COLLABORATION W/ NEIGHBORING OFFICES
WENT FLOOD WATCH RATHER THAN FLASH FLOOD WATCH...ALTHOUGH SOME
LOCALIZED FLASH FLOODING CAN`T BE RULED OUT LT TNGT OR SUN ESP IN
URBAN AREAS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY/...
ON SUNDAY...LITTLE CHANGE SEEN IN OVERALL PATTERN WITH YET ANOTHER
S/W ENHANCING RAINFALL PTNTL ALONG COASTAL SECTIONS...BUT AREAS
FARTHER INLAND MAY TEND TO SEE MORE BREAKS AND LESS COVERAGE OF
PRECIP AS FORCING IS EXPECTED TO REMAIN FARTHER EAST THAN PAST 2
DAYS. A BIT WARMER INLAND AS PCPN SHOULD BECOME A BIT MORE SPOTTY
IN NATURE. HIGHS U70S/LOWER 80S EAST TO LWR/MID 80S ALONG/WEST OF
I-95.
LOWS SUN NIGHT 65-70 F WITH HIGHEST PCPN CHCS ALONG THE
COAST...HAVE SCALED BACK TO ONLY 20-30% CHC POPS NW 1/2 OF THE CWA
AFTER MIDNIGHT.
FOR MON/TUE...GFS/ECMWF DIFFER AS TO EXTENT OF SFC TROUGHING
REMAINING ALONG THE COAST...LIKELY DUE TO UNCERTAINTIES WITH
RESPECT TO WHERE TC BERTHA WILL BE LOCATED. WILL RETAIN CHC POPS
ALL AREAS MON BUT WILL STILL FOCUS HIGHEST POPS ALONG THE COAST.
ON TUE...A LOW CONFIDENCE FORECAST AS LATEST ECMWF IS WETTER AS
TROUGH STRENGTHENS AND PUSHES DEEPER MOISTURE BACK N INTO THE MID
ATLC WHILE GFS IS GENLY DRY. WILL RETAIN SLIGHT CHC TO LOW CHC
POPS MOST AREAS WITH HIGHS MON MAINLY IN THE MID-UPPER 80S AND
HIGHS TUE 85-90 F.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
A BRIEF DRY PERIOD IS EXPECTED TUE NIGHT INTO EARLY WED AS THE MID
ATLANTIC REGION SITS BTWN THE DEPARTING FRONTAL BOUNDARY AND ANOTHER
APPROACHING COLD FRONT FROM THE NW. THIS FRONT IS EXPECTED TO CROSS
THE AREA LATE DAY WED INTO THU MORNING...AND THEN GET STRETCHED
ACROSS THE CAROLINAS LATER THU INTO FRI. SCATTERED
SHOWERS/THUNDERSTORMS WILL BE POSSIBLE AREAWIDE ON WED...THEN PRECIP
GETS SHUNTED SOUTH ALONG THE VA/NC BORDER AND POINTS SWD FOR
THU/FRI. HIGH PRESSURE BUILDS BACK INTO THE REGION FROM THE NW LATE
FRI INTO NEXT WEEKEND. HIGH TEMPERATURES WILL BE NEAR NORMAL WED
(UPPER 80S TO LOWER 90S) AND THEN COOL UP TO 5 DEGREES BELOW NORMAL
FOR THU-SAT (GENERALLY IN THE 80S). LOW TEMPERATURES TUE/WED NIGHTS
WILL AVERAGE OUT IN THE UPPER 60S TO LOWER 70S AND THEN EXPERIENCE A
SLIGHT COOL DOWN WITH LOWS GENERALLY IN THE 60S THU/FRI NIGHTS.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
A STATIONARY FRONTAL BOUNDARY WILL REMAIN INVOF SE VA AND NE NC
TODAY. LIGHT TO MODERATE RAIN WILL CONTINUE TO MOVE NORTHWARD
ACROSS EASTERN VA AND THE DELMARVA THRU 12Z...ESPECIALLY EAST OF
INTERSTATE 95. CONDS EXPECTED TO REMAIN IFR DURING THIS
TIME...EXCEPT ONLY MVFR AT KECG. FOR THE REST OF TODAY...PRECIP
WILL LARGELY BE CONFINED TO FAR SE VA AND NE NC WITH SOME
IMPROVEMENT IN CONDITIONS ELSEWHERE.
MVFR/IFR CONDITIONS EXPECTED TONIGHT INTO MONDAY AS THE FRONTAL
BOUNDARY REMAINS NEARBY. IMPROVED CONDITIONS TUESDAY AND WEDNESDAY
AS THE BOUNDARY MOVES OFFSHORE.
&&
.MARINE...
A FRONTAL BOUNDARY WILL REMAIN INVOF THE MID-ATLANTIC COAST THROUGH
MONDAY. NO FLAGS ARE EXPECTED AS WIND SPEEDS REMAIN GENERALLY BELOW
15 KT. SEAS 2-4 FT WITH WAVES 1-2 FT. THE FRONT GETS PULLED
OFFSHORE BY TROPICAL STORM BERTHA BY TUESDAY AS IT STAYS WELL EAST
OF THE OUTER BANKS...AND ALSO AS HIGH PRESSURE BUILDS INTO THE
REGION FROM THE NW. SOME LONG PERIOD SWELL COULD ENCROACH THE AREA
DEPENDING ON THE STRENGTH/TRACK OF TROPICAL STORM BERTHA. CURRENT
WAVEWATCH GUIDANCE BRINGS 4-5 FT SWELL OUT NEAR 20 NM LATE
TUESDAY/TUESDAY NIGHT. ANOTHER COLD FRONT APPROACHES FROM THE NW
WEDNESDAY AND MOVES TWD THE VA/NC BORDER BY THURSDAY. OVERALL SUB-
SCA CONDITIONS ARE EXPECTED TO PREVAIL THROUGH NEXT WEEK WITH THE
EXCEPTION OF MINOR AFFECTS FELT BY THE PASSING OF TROPICAL STORM
BERTHA.
&&
.HYDROLOGY...
PERIODIC RAINFALL ALONG A SLOW-MOVING FRONTAL BOUNDARY WILL
CONTINUE TO BRING ACCUMULATING PRECIPITATION TO THE REGION TODAY
THROUGH MONDAY. HIGHEST ACCUMULATIONS FOCUSED OVER NE NC AND SE
VA WITH ADDNTL QPF AMTS BTWN 1.5-2.5 INCHES (LCLLY HIGHER IN
TRAINING ECHOES) PRIMARILY OVER THE NEXT 24 HRS.
RAISED FLOOD WATCH IN AREAS THAT HAVE GENLY RECEIVED 2-4" OVER PAST
24 HRS WHERE ADDITIONAL SIGNIFICANT RAINFALL AMOUNTS MAY RESULT IN
FLOODING OF URBAN AREAS...AREAS OF POOR DRAINAGE...LOW LYING
AREAS...AND TO RISES OF SMALL STREAMS/CREEKS. WILL CONTINUE TO
HIGHLIGHT LOCALLY HEAVY RAINFALL POTENTIAL FOR AREAS NOT IN THE
WATCH IN THE HWO.
&&
.CLIMATE...
COOL DAYTIME TEMPERATURES FOR EARLY AUGUST...COMING CLOSE TO
CHALLENGING RECORDS. FOR REFERENCE...THE RECORD LOW MAXIMUM
TEMPERATURES FOR TODAY/AUGUST 2ND:
RICHMOND....74 F (1903).
NORFOLK.....74 F (1916).
SALISBURY...74 F (1959).
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR MDZ025.
NC...FLOOD WATCH THROUGH THIS EVENING FOR NCZ013>017-030>032-102.
MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR NCZ102.
VA...FLOOD WATCH THROUGH THIS EVENING FOR VAZ095>100.
MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR VAZ098>100.
MARINE...NONE.
&&
$$
SYNOPSIS...ALB/LKB
NEAR TERM...ALB/LKB
SHORT TERM...LKB/MPR
LONG TERM...BMD
AVIATION...JDM
MARINE...JDM
HYDROLOGY...AKQ
CLIMATE...AKQ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
352 AM EDT SUN AUG 3 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 351 AM EDT SUN AUG 3 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW NW FLOW OVER THE
UPR LKS BTWN TROF CENTERED OVER QUEBEC AND MEAN RDG OVER THE
ROCKIES. DESPITE SHARP MID LVL INVRN/VERY DRY MID LVLS SHOWN ON THE
00Z GRB RAOB ASSOCIATED WITH SHRTWV RDG PASSING THRU THE UPR LKS
THAT IS BRINGING MOCLR CONDITIONS TO UPR MI...THERE ARE SOME ISOLD
SHOWERS OVER WI AND FAR WRN UPR MI IN ADVANCE OF A SHRTWV DROPPING
SEWD THRU SRN MN. A STRONGER SHRTWV EMBEDDED IN THE NW FLOW ALF IS
MOVING ESEWD THRU NW ONTARIO...WITH ATTENDANT RATHER WEAK SFC-H85
COLD FNT MOVING INTO NRN MN. THERE WERE SOME SHOWERS/TS LAST EVNG
OVER FARN NRN MN/ADJOINING ONTARIO IN ADVANCE OF THIS FNT IN THE
FAIRLY MOIST ENVIRONMENT DEPICTED ON THE 00Z INL RAOB /00Z PWAT WAS
1.25 INCH OR ALMOST 150 PCT OF NORMAL AND KINX WAS 32/...BUT LOSS OF
DAYTIME HEATING...PASSAGE OF SHARPER FORCING TO THE N AND ABSENCE OF
SGNFT H85-7 MSTR INFLOW NECESSARY TO SUSTAIN NOCTURNAL CONVECTION
HAVE CAUSED THESE SHOWERS TO DIMINISH ALMOST ENTIRELY EARLY THIS
MRNG IN AN ENVIRONMENT WHERE MUCAPE IS 100-250 J/KG AT BEST.
MAIN FCST CONCERNS THRU TNGT ARE FOCUSED ON POPS ASSOCIATED WITH
APRCHG COLD FNT.
TODAY...SHRTWV OVER ONTARIO IS PROGGED TO CONTINUE ESEWD...WITH
ATTENDANT SFC COLD FNT ON A LINE THRU NW LK SUP AT 12Z THIS MRNG
FCST TO REACH THE SE CWA BY LATE THIS AFTN. WL CARRY ONLY ISOLD
SHOWERS THIS MRNG OVER THE NW CWA ASSOCIATED WITH THE FROPA GIVEN
PRESENT COVERAGE ALONG THE FNT AND PASSAGE OF SHARPER FORCING TO THE
N. BUT AS THE FNT/MID LVL COMMA TAIL MSTR RIBBON PRESSES TO THE SE
THIS AFTN IN THE PRESENCE OF DAYTIME HEATING...EXPECT THE SHOWER/TS
COVERAGE TO INCRS. INTERACTION BTWN THE FNT AND LK BREEZE BNDRYS
THAT WL SHARPEN THE LLVL CNVGC WL ALSO AID THE CONVECTION. BOTH THE
00Z NAM/LOCAL WRF-ARW MODELS INDICATE THE LI WL DROP AS LO AS -6 TO
-8C AS MUCAPES REACH ARND 2500 J/KG THIS AFTN OVER THE SCNTRL CWA...
JUSTIFYING THE GOING LIKELY POPS IN THE CURRENT FCST FOR THAT AREA
THIS AFTN. WITH SFC-6KM BULK SHEAR AS HI AS 30 KTS...THERE COULD BE
SOME STRONGER CELLS. WITH SFC TEMPS RISING TO 80-85 AHEAD OF THE FNT
RESULTING IN ADIABATIC LAPSE RATES IN THE PBL...GUSTY WINDS SHOULD
BE THE MAIN THREAT. BUT MARGINAL LAPSE RATES AND SHEAR INDICATE SVR
WX IS NOT LIKELY.
TNGT...ARRIVAL OF SOME DRYING ALF FOLLOWING THE FROPA AND LOSS OF
DAYTIME HEATING SHOULD RESULT IN LINGERING POPS OVER THE SE CWA
DIMINISHING THIS EVNG. BUT SINCE SEVERAL MODELS SHOW ANOTHER
WEAKER SHRTWV DROPPING SEWD IN THE NW FLOW ALF AND ASSOCIATED
DPVA/DEEP LYR QVECTOR CNVGC IMPACTING THE CWA OVERNGT...WL RETAIN
SOME LOWER CHC POPS MAINLY OVER THE SRN TIER CLOSER TO THE HIER
LINGERING PWAT AOA AN INCH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 351 AM EDT SUN AUG 3 2014
GENERALLY QUIET WEATHER EXPECTED THROUGH THE EXTENDED WITH DRY
WEATHER AND MODERATING TEMPERATURES EXPECTED. ISOLATED SHOWERS AND
THUNDERSTORMS ARE POSSIBLE NEAR THE WISCONSIN BORDER DURING THE DAY
MONDAY AS A SHORTWAVE PASSES THROUGH THE BROAD TROUGHING STILL IN
PLACE OVER MUCH OF THE EASTERN U.S. THE BETTER FORCING AN MOISTURE
IS EXPECTED TO REMAIN MAINLY SOUTH OF THE REGION AS THE VORT MAX
SWINGS THROUGH...HOWEVER...IT WILL BRUSH CLOSE ENOUGH TO THE U.P./WI
BORDER TO KEEP SLIGHT POPS IN THE FORECAST. ANOTHER SHORTWAVE IS
PROGGED TO ROTATE AROUND THE TROUGH TUESDAY
NIGHT...HOWEVER...CONDITIONS WILL REMAIN DRY AS THIS WILL SWING
THROUGH DURING THE COOLER OVERNIGHT HOURS WITH VERY LIMITED MOISTURE
AVAILABLE DURING THAT TIME.
THE REMAINDER OF THE EXTENDED...WEDNESDAY THROUGH SATURDAY WILL BE
DOMINATED BY BROAD SURFACE HIGH PRESSURE ALONG WITH UPPER LEVEL
500MB RIDGING SLIDING FROM THE WESTERN U.S. INTO THE CENTRAL U.S.
THIS WILL ALLOW TEMPERATURES TO WARM TO NEAR OR SLIGHTLY ABOVE
NORMAL BY THE END OF THE WORK WEEK AND INTO THE UPCOMING WEEKEND.
CONDITIONS WILL REMAIN DRY AS DRY AIR REMAINS IN PLACE ACROSS THE
GREAT LAKES REGION THROUGH THIS TIME PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 126 AM EDT SUN AUG 3 2014
DRY HI PRES WILL MAINTAIN VFR CONDITIONS AND LGT WINDS AT TAF SITES
OVERNIGHT. MID CLDS IN ADVANCE OF AN APRCHG DISTURBANCE/COLD FNT WL
ARRIVE LATE TNGT WHILE ISOLD TO SCT SHRA MOVE ACROSS THE AREA ON
SUNDAY WITH THE FRONTAL PASSAGE. GIVEN UNCERTAINTY OF THE SHRA
COVERAGE ALONG THE FRONT ON SUNDAY HAVE ONLY MENTIONED VCSH IN THE
TAFS. INCLUDED VCTS IN KSAW WHERE THERE WILL BE BETTER INSTABILITY
AND ENHANCED CONVERGENCE ALONG POSSIBLE LAKE BREEZE BOUNDARIES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 351 AM EDT SUN AUG 3 2014
TYPICAL SUMMER TYPE FLOW REGIME/WEAK PRES GRADIENT WILL KEEP WINDS
UNDER 15 KT THROUGH MUCH OF THIS COMING WEEK. SOME PATCHY FOG IS
POSSIBLE INTO MON...ESPECIALLY IF RAIN FALLS TODAY. BUT ANY
WIDESPREAD DENSE FOG IS UNLIKELY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KEC
AVIATION...VOSS
MARINE...KC
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1207 AM CDT Sun Aug 3 2014
.UPDATE...
Issued at 1207 AM CDT SUN AUG 3 2014
Convection is developing over the Mid-Missouri River Valley near
Omaha ahead of a weak vort max dropping in from the north. HRRR has
had a good handle on this convection and brings it into northwest MO
and toward the KC area later tonight toward sunrise. 00Z TOP sounding
indicates a deep enough unstable layer in the boundary layer that
shallow decoupling shouldn`t have much effect on MUCAPE values which
are progged to be around 1000 J/kg. Have therefore bumped PoPs up to
as high as 50 percent across northwest MO late tonight and into the
chance category as far south as the KC metro early Sunday morning.
&&
.DISCUSSION...
Issued at 259 PM CDT SAT AUG 2 2014
Tonight through Sunday: As of early this afternoon, a shallow
cumulus field has developed over much of the area. Some of this
activity is slightly more enhanced across eastern Kansas, and may
spawn a few light showers just west of the forecast area through
early evening. A decaying area of showers continues to push southward
over far southeast Nebraska, but is not expected to gain intensity or
coverage. Outside of far northwestern sections of the CWA, the
trajectory should keep most areas dry through this evening. Models
show a weak shortwave trough to move across the region late tonight
into tomorrow morning. Have continued a slight chance for
thunderstorms over the northwest quarter of the forecast area
tonight into tomorrow as this feature moves through, but most
locations should remain dry. Otherwise, similar temperatures are
expected on Sunday, with highs warming into the middle 80s to near 90
degrees.
Monday/Tuesday: Northwest flow aloft with continue over the region,
with maximum temperatures increasing daily with readings in the
upper 80s to middle 90s. Slight chances for thunderstorms will
continue for most sections each day as projected subtle upper
disturbances within the northwest flow move across the area.
Coverage of precipitation is not expected to be widespread nor
persistent for lengthy periods of time.
Wednesday through Saturday: The extended forecast features
increasing probabilities for precipitation with persistent northwest
flow aloft. The general pattern as advertised by numerical models
suggest several upper disturbances to move across the region during
the period, with one or more thunderstorm complexes to develop
upstream and move into portions of the area. Additional
thunderstorms may develop along a quasi-stationary frontal boundary
oriented northwest-southeast, located over or just southeast of the
forecast area. While uncertainty remains with regards to the
specifics, the overall pattern provides increasing confidence for
measurable rainfall for many locations during the extended period,
especially during the Wednesday/Thursday timeframe. In addition,
temperatures will be cooler than earlier in the week with readings
closer to or slightly cooler than seasonal averages.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1207 AM CDT SUN AUG 3 2014
Thunderstorms developing near Omaha appear poised to hold together
longer than previously anticipated and could affect the STJ and KC
areas toward sunrise. Chances for storms at these airports are
running around 30 to 40 percent, and therefore introduced VCTS to the
TAFs early Sunday morning. If this activity continues to hold
together prevailing or tempo groups will be needed. Any storms this
far south should be fairly weak in intensity.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
UPDATE...Hawblitzel
DISCUSSION...Blair
AVIATION...Hawblitzel
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1226 AM CDT SUN AUG 3 2014
.SYNOPSIS...
ISSUED AT 320 PM CDT SAT AUG 2 2014
THE WESTERN CONUS RIDGE/EASTERN CONUS TROUGH PATTERN CONTINUES IN
THE UPPER LEVELS WITH THE CENTRAL PLAINS UNDER THE INFLUENCE OF
NORTHWEST FLOW WITH WEAK SHORTWAVES PERIODICALLY MOVING OVER THE
RIDGE AND ACROSS THE AREA AS THEY DIVE INTO THE TROUGH. AT
19Z...NOTING A SHORTWAVE TROUGH MOVING INTO NORTHERN SOUTH
DAKOTA...WITH ANOTHER OVER SOUTHERN WYOMING. 02.12Z SOUNDINGS SHOWED
700MB TEMPERATURES OF 9C AND 8C AT KUNR AND KLBF RESPECTIVELY...WITH
5C AND 6C AT KABR AND KOAX. THIS WOULD INDICATE THAT ALTHOUGH THE
AREA IS UNDER NORTHWEST FLOW...THE WARM AIR ALOFT UNDER THE RIDGE
CONTINUES TO STAY IN PLACE ACROSS THE WESTERN PLAINS. HOWEVER...THIS
AIR IS NOT WARM ENOUGH TO CAP THE BOUNDARY LAYER. AT THE
SURFACE...LOW PRESSURE WAS SITUATED OVER SOUTH CENTRAL SOUTH
DAKOTA...JUST NORTH AND EAST OF KVTN WITH A WEAK TROUGH OF LOW
PRESSURE EXTENDING SOUTH THEN WEST /TO AROUND KBBW THROUGH KLBF AND
KOGA. STRONG HEATING AT THE SURFACE WITH HIGHS IN THE UPPER 80S AND
LOW 90S HAS CREATED DEEP MIXING UP TO 600MB AND WITH STEEP LAPSE
RATES CONVECTION HAS BEGUN TO DEVELOP ACROSS THE AREA WHERE
CONVERGENT BOUNDARIES EXIST. MU CAPES ARE 1500 TO 2000 J/KG BUT
THERE IS VERY LITTLE SHEAR OVER ONGOING CONVECTION SO ACTIVITY HAS
BEEN VERY UNORGANIZED THUS FAR THIS AFTERNOON.
&&
.UPDATE...
ISSUED AT 828 PM CDT SAT AUG 2 2014
THUNDERSTORMS IN SOUTH CENTRAL SOUTH DAKOTA ARE PRODUCING LARGE
HAIL...SO WE HAVE UPDATED THE FORECAST FOR NORTH CENTRAL NEBRASKA
TO INCLUDE THE POSSIBILITY OF SEVERE THUNDERSTORMS.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 320 PM CDT SAT AUG 2 2014
SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH THE AFTERNOON AND
INTO THIS EVENING UNTIL LOSS OF DAYTIME HEATING STABILIZES THE
BOUNDARY LAYER AND CUTS OFF THE ENERGY INTO THE STORMS. THE SURFACE
LOW OVER SOUTH DAKOTA WILL SLOWLY MOVE SOUTHEAST THROUGH THE EVENING
WITH THE PRECIPITATION GENERALLY STAYING ALONG AND SOUTH OF AN ARC
FROM THE LOW TO KTIF TO KAIA. PRECIPITATION CHANCES WILL SLIDE SOUTH
AND EAST THROUGH THE EVENING...AND SHOULD GENERALLY BE DONE BY 06Z.
THE RAP AND THE NAM DO INDICATE AN INCREASE IN DEEP LAYER SHEAR AS A
SHORTWAVE TROUGH OVER THE DAKOTAS SLIDES SOUTHEAST THIS EVENING. IS
NOT OUT OF THE QUESTION TO GET AN ISOLATED STORM THAT IS ABLE TO GET
ORGANIZED AND PRODUCE HAIL OR STRONG WINDS...BUT FEEL IT WILL BE
SHORT LIVED AND NO REAL THREAT FOR SEVERE STORMS IS CURRENTLY A
CONCERN.
AS THE SHORTWAVE OVER SOUTH DAKOTA MOVES SOUTHEAST INTO NORTHERN
NEBRASKA LATER THIS EVENING AND OVERNIGHT THERE ARE INDICATIONS OF
WARM AIR ADVECTION AND STRONGER LIFT AHEAD OF IT...ALONG WITH
MOISTURE TRANSPORT IN THE 850MB TO 700MB LAYER. ALTHOUGH NONE OF
THIS IS REAL STRONG COULD GET MORE CONVECTION TONIGHT. IF IT DOES
DEVELOP...ONE QUESTION WILL BE HOW FAR WEST IT WILL BE. CURRENT
SUITE OF MODELS SHOW MOST OF THIS ACTIVITY WILL JUST SKIRT THE LOCAL
FORECAST AREA...MAINLY KEEPS IT OVER NORTHEAST NEBRASKA.
THEN FOR SUNDAY...NOT MUCH CHANGE IN THE GENERAL WEATHER PATTERN.
TEMPERATURES ALOFT WARM SLIGHTLY BUT NOT MUCH SO STILL LOOKING FOR
HIGHS NEAR 90 OR IN THE LOW 90S MOST LOCATIONS. WITH THE EXCEPTION
OF THE GFS...MODELS ARE ALL DEVELOPING CONVECTION IN THE AFTERNOON
ALONG A WEAK SURFACE FRONT FROM NORTHWEST TO SOUTH CENTRAL NEBRASKA.
STRONG DAYTIME HEATING WILL AGAIN DESTABILIZE THE LOW LEVELS OF THE
TROPOSPHERE AND WILL CREATE STEEP LAPSE RATES WITH MIXING TO NEAR
650MB. ALSO...THERE IS A WEAK SHORTWAVE PROJECTED TO MOVE INTO
NORTHWEST NEBRASKA NEAR MID AFTERNOON TO ENHANCE THE LIFT IN THE
AREA. AS SIMILAR CONDITIONS OVER THE PAST SEVERAL DAYS HAVE CAUSED
DEVELOPMENT OF ISOLATED TO SCATTERED SHOWER AND THUNDERSTORM
ACTIVITY SEE NO REASON WHY IT WON/T OCCUR AGAIN SUNDAY AFTERNOON AND
HAVE ADDED CHANCES FOR PRECIPITATION INTO THE FORECAST.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 320 PM CDT SAT AUG 2 2014
SUNDAY NIGHT...WRN STATES UPPER RIDGE AXIS BUILDS EWD AS UPPER LOW
OVER SERN CANADA ALSO SHIFTS EWD. SURFACE HIGH PRESSURE BEGINS TO
SLIDE SWD INTO THE GREAT LAKES AND UPPER MISSISSIPPI VALLEY WHICH
ALLOWS A WEAK BOUNDARY TO BACK WWD INTO THE NERN PORTION OF THE FCST
AREA SUNDAY NIGHT INTO MONDAY. AS THIS HAPPENS...LEE SIDE LOW
PRESSURE REDEVELOPS ACROSS THE NRN HIGH PLAINS SETTING UP A
BAROCLINIC ZONE ALONG THE PERIPHERY OF THE ERN SIDE OF THE UPPER
RIDGE AXIS...ACROSS THE DAKOTAS AND NRN NEBRASKA. THE ULTIMATE
PLACEMENT OF THIS FRONTAL BOUNDARY WILL BE KEY TO THE PRECIPITATION
FCST THROUGH THE WEEK AND IS DISCUSSED FURTHER BELOW. MODELS ARE
SIMILAR WITH THIS PLACEMENT BY MONDAY THOUGH DIFFER BEYOND. THE NRN
PORTION OF THIS BOUNDARY BECOMES CO-LOCATED WITH AN AREA OF MID
LEVEL FRONTOGENESIS SUNDAY EVE WHICH WILL HELP TO GENERATE DEEP
LAYER LIFT AND A BETTER CHC OF THUNDERSTORMS NORTH OF NEB SUNDAY
EVE. HOWEVER...UPPER NW FLOW HAS GENERATED ISOLATED THUNDERSTORMS IN
THE CURRENT PATTERN DUE TO WEAK BOUNDARY INTERACTIONS AND STEEP
LAPSE RATES ALOFT...AND WOULD EXPECT A SIMILAR SCENARIO FOR SUNDAY
EVE FURTHER SOUTH INTO WESTERN AND NORTH CENTRAL NEB...AND THEREFORE
SLIGHT CHANCES FOR THUNDERSTORMS WILL BE IN THE FCST BEFORE MIDNIGHT
SUNDAY. MIN TEMPS SUNDAY NIGHT NEAR TO SLIGHTLY ABOVE AVERAGE FOR THIS
TIME OF YEAR.
MONDAY INTO TUESDAY THE SHIFT IN THE RIDGE AXIS ALONG THE FRONT
RANGE ALLOWS SUBSIDENCE AND DRYING TO OCCUR OVER THE HIGHER TERRAIN
FURTHER WEST. THIS IN TURN WILL ALLOW FOR A RETURN OF THE NOCTURNAL HIGH
PLAINS LLJ WHICH DEVELOPS IN RESPONSE TO THE MORE RAPID COOLING OF
THE HIGHER TERRAIN IN THE EVENING COMPARED TO A MORE MOIST
ATMOSPHERE FURTHER EAST. THIS LLJ ALSO STRENGTHENS IN RESPONSE TO
UPPER PV ANOMALIES ROUNDING THE NOW FLATTENED RIDGE WITH ASSOCIATED
SFC CYCLOGENESIS FAVORING THE WY/CO FRONT RANGE AND WRN HIGH PLAINS
BY MID WEEK. THIS ALL SETS THE STAGE FOR INCREASED THUNDERSTORM
DEVELOPMENT...ESPECIALLY DURING THE LATE EVENING AND OVERNIGHT
HOURS...MONDAY AND TUESDAY AND ON INTO THE REST OF THE WEEK. THE
PREVIOUSLY MENTIONED FRONTAL BOUNDARY CONTINUES TO SAG FURTHER SWD
AND EVENTUALLY ACROSS THE WESTERN AND NORTH CENTRAL PORTION OF
NEBRASKA DURING MID WEEK. THE LLJ WILL BE EFFICIENT AT SUPPLYING LOW
LEVEL MOISTURE TO THE ATMOSPHERE WHICH WILL BE FURTHER ENHANCED BY
TROPICAL MOISTURE MOVING NWD THROUGH THE GREAT BASIN AREA AROUND THE
AFOREMENTIONED UPPER HIGH. THE RESULT IS PW VALUES APPROACHING +2
STANDARD DEVIATIONS ABOVE THE MEAN FOR THIS TIME OF YEAR...NEARING
1.75 INCHES BY THU. IN ADDITION...MODEST INSTABILITY DEVELOPS E OF
THE STATIONARY/WARM FRONTAL BOUNDARY IN ERN NEB EARLY IN THE WEEK
BUT SHIFTS SWWD BY WED/THU TIME FRAME AS DOES THE BOUNDARY. THE
SPECIFIC DETAILS OF BOUNDARY LOCATION FROM DAY TO DAY WILL BE
DETERMINED LARGELY BY EACH ITERATION OF CONVECTIVE DEVELOPMENT AS
MESOSCALE COLD POOL AUGMENTATION OF THE BOUNDARY TAKES
PLACE...MAKING SPECIFIC DETAILS OF THUNDERSTORM DEVELOPMENT
DIFFICULT. IN GENERAL...THE DEVELOPING LARGE SCALE PATTERN BY MID
WEEK SUPPORTS AN INCREASED CONFIDENCE IN INCREASING THUNDERSTORM
CHANCES THROUGH THE WEEK. DAYTIME MAX TEMPERATURES WILL BE AVERAGE
TO SLIGHTLY ABOVE TO START THE WEEK...BUT WILL LOWER TO BELOW
AVERAGE BY THE END OF THE WEEK. THE DIURNAL RANGE OF TEMPS AS THE
WEEK PROGRESSES HOWEVER LESSENS WITH LOWS REMAINING NEAR OR ABOVE
AVERAGE THROUGH THE WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1226 AM CDT SUN AUG 3 2014
ISOLATED THUNDERSTORMS IN NORTH CENTRAL NEBRASKA...AROUND ONL...WILL
DISSIPATE BY 10Z. AFTER THAT...RESIDUAL MOISTURE FROM THE RAIN COULD
RESULT IN AREAS OF FOG WITH LOCALIZED VISIBILITY LESS THAN 1SM.
HOWEVER...THE SHORT RANGE PROJECTIONS INDICATE THAT IT WILL BE NORTH
AND EAST OF A VTN-TIF-BBW LINE.
WITH NO SIGNIFICANT CHANGE IN THE WEATHER PATTERN...ISOLATED
THUNDERSTORMS CAN BE EXPECTED AGAIN SUNDAY EVENING. HOWEVER...WITH
MUCH UNCERTAINTY IN THE LOCATION AND TIMING...THEY WILL NOT BE
INCLUDED IN THE TERMINAL FORECASTS FOR LBF AND VTN AT THIS TIME.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SPRINGER
SYNOPSIS...BROOKS
SHORT TERM...BROOKS
LONG TERM...JWS
AVIATION...SPRINGER
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1147 PM MDT SAT AUG 2 2014
.AVIATION...
06Z TAF CYCLE
SHRA AND ISOLATED LOW-TOPPED TSRA OVER FAR SW NM JUST AROUND 06Z
SHOULD EXPAND IN COVERAGE AND SLOWLY TRACK NORTH DURING THE
OVERNIGHT INTO SUNDAY AM. ENOUGH CONFIDENCE TO INCLUDE A MENTION AT
KGUP AFTER DAYBREAK GIVEN GOOD RUN-TO-RUN CONSISTENCY IN
MODELS....BUT LOWER CONFIDENCE ON PRECISE TIMING AND HAVE TARGETED
14Z-15Z AS FIRST GUESS. ELSEWHERE... WEAK UPSLOPE REGIME THAT HAD BEEN
IN PLACE EAST OF THE CENTRAL MOUNTAIN CHAIN HAS YIELDED SOME VERY
SPOTTY LIGHT SHOWERS AT KLVS AS WELL AS NEAR KROW PAST FEW HOURS. WILL
NOT INCLUDE A VC PLACEHOLDER AT EITHER SITE THOUGH VFR MID LEVEL
CIGS MAY LINGER A LITTLE LONGER THAN EXPECTED...ESPECIALLY KROW.
OTHERWISE...TRENDED KFMN...KSAF AND ABQ AREA TERMINAL FORECASTS TO
REFLECT AN INCREASE IN MAINLY MID-LEVEL CLOUD COVER AFT 12Z BEFORE
DIURNAL TRENDS PREDOMINATE AFTER 18Z. FOCUS FOR CONVECTION SUN PM WILL
AGAIN BE ACROSS THE WEST... WITH A MORE ACTIVE ROUND OF SHRA/TSRA
AS COMPARED TO SATURDAY. KJ
&&
.PREV DISCUSSION...300 PM MDT SAT AUG 2 2014...
.SYNOPSIS...
ABUNDANT MOISTURE WILL LINGER OVER NEW MEXICO THROUGH EARLY NEXT
WEEK...AND SLOW MOVING STORMS WILL CONTINUE TO BE CAPABLE OF
PRODUCING LOCALLY HEAVY RAIN...WHICH COULD LEAD TO FLASH FLOODING.
AREAS ALONG AND WEST OF THE CONTINENTAL DIVIDE WILL BE THE FOCUS FOR
THE HEAVIER STORMS TONIGHT AND INTO SUNDAY...WHILE THE FOCUS SLOWLY
SHIFTS TO THE NORTHWEST THIRD TO HALF SUNDAY NIGHT...AND PORTIONS OF
THE WEST AND CENTRAL MONDAY. HIGH TEMPERATURES WILL REMAIN BELOW
AVERAGE THROUGH MONDAY. A WARMING AND DRYING TREND IS EXPECTED BY
THE MIDDLE OF NEXT WEEK.
&&
.DISCUSSION...
ABUNDANT CLOUD COVER LINGERING THIS AFTERNOON...AND LAPS SHOWING THE
EAST REMAINING STABLE SO FAR. CELLS HAVE BEEN FIRING ALONG/WEST OF
THE CENTRAL MT CHAIN AND MOST NOTABLY OVER WESTERN SOCORRO COUNTY TO
THE GALLUP AREA...BUT LESS ACTIVE OVERALL COMPARED TO THIS TIME THE
LAST COUPLE OF DAYS. PWATS FROM AREA 12Z SOUNDINGS SHOWED LITTLE
CHANGE FROM FRIDAY ALTHOUGH MID LEVEL WINDS ARE TRANSITIONING AS THE
WEAK UPPER LOW PREPARES TO MOVE NORTH INTO ARIZONA. INITIAL THOUGHTS
WERE THAT THE CURRENT FLASH FLOOD WATCH MAY HAVE NEEDED TO BE
EXPANDED NORTHWARD AND SOMEWHAT EASTWARD FOR TONIGHT...BUT 12Z LOCAL
WRF...NAM AND HRRR DON/T SUPPORT THAT IDEA AND ARE RATHER SPARSE
LOOKING IN AREAL COVERAGE. THEREFORE DECIDED TO LET THE CURRENT
WATCH RIDE...WHERE MOST OF THIS AFTERNOON/S ECHOS EXIST SO FAR.
SUNDAY/SUNDAY EVENING COULD BE QUITE ACTIVE ALONG AND WEST OF THE
CONTINENTAL DIVIDE AND CAN/T RULE OUT THE POTENTIAL FOR HEAVY RAIN
OVER THAT AREA...HOWEVER STORM MOTION LOOKS TO BE GENERALLY SOUTH TO
NORTH AT 10 TO 15 MPH. MODELS SUGGEST THE EAST WILL CONTINUE TO BE
FAIRLY QUIET. AS THE UPPER LOW MOVES INTO THE GREAT BASIN
MONDAY...THE THETA-E RIDGE AXIS SHIFTS MORE SOUTHWEST TO NE OVER NEW
MEXICO...PUTTING THE FOCUS FOR STORMS MORE INTO THE NORTHWEST AND
NORTH CENTRAL AND ALLOWING THEM TO DRIFT OFF THE MTS INTO THE
NORTHEAST AND CENTRAL HIGHLANDS. THE MID TO LATE WEEK PERIOD STILL
FEATURES A SUPPRESSION OF THE RIDGE...ALLOWING THE NORTHWEST TO DRY
OUT SOME...AND A DECREASE OVERALL IN CONVECTION. HIGH TEMPERATURES
SHOULD FINALLY EXPERIENCE A REBOUND TOWARDS NORMAL FOR THE FIRST
WEEK OF AUGUST.
&&
.FIRE WEATHER...
A WET AND ACTIVE MONSOON PATTERN WILL CONTINUE OVER THE NEXT FEW
DAYS...KEEPING CRITICAL FIRE WEATHER CONDITIONS FROM DEVELOPING.
FOOTPRINTS OF WETTING RAINFALL HAVE BEEN SCATTERED EACH DAY OVER THE
PAST WEEK...BUT MOST AREAS OUTSIDE OF THE EASTERN PLAINS HAVE SEEN
PRECIPITATION ON OCCASION. WINDS WILL REMAIN LIGHT FOR THE MOST
PART...ONLY GETTING SLIGHTLY BREEZY IN THE VICINITY OF CENTRAL
GAPS/CANYONS THIS EVENING...AND OF COURSE GUSTY WITH ANY BRIEF AND
LOCALIZED THUNDERSTORM OUTFLOWS. THE FOCUS FOR STORMS WILL BE IN
SOUTHWESTERN SECTIONS OF THE FORECAST AREA TODAY AND
TONIGHT...SHIFTING TO THE WESTERN THIRD OF THE STATE SUNDAY.
THE BEST PLUME OF MOISTURE ALOFT WILL THEN BEGIN TO GRADUALLY LAY
OVER OR TOPPLE TO MORE OF A SOUTHWEST-NORTHEAST ORIENTATION MONDAY
AND TUESDAY...WITH STORMS STRETCHING FROM THE SW MOUNTAINS TO THE
NORTHERN MOUNTAINS BOTH DAYS. STORMS WILL ALSO PERIODICALLY BE
FILLING IN BETWEEN THESE AREAS. SOME LEE SIDE SURFACE TROUGHING WILL
ALLOW MODERATE BREEZES TO DEVELOP IN THE NORTHEAST MONDAY AND
TUESDAY. OVERALL HUMIDITY TRENDS WILL NOT VARY MUCH THROUGH THE NEXT
FEW DAYS WITH GOOD TO EXCELLENT RECOVERIES IN MUCH OF THE FORECAST
AREA EACH NIGHT/MORNING...ESPECIALLY WITHIN AREAS THAT RECEIVE
WETTING RAIN. BELOW AVERAGE TEMPERATURES ARE ALSO EXPECTED TO
CONTINUE THROUGH TUESDAY...KEEPING DAYTIME HUMIDITY FAIRLY ELEVATED
THROUGH TUESDAY. SOME DAY-TO-DAY DRYING IS THEN EXPECTED WEDNESDAY
THROUGH THE END OF NEXT WEEK. THIS WILL ALLOW TEMPERATURES TO START
CLIMBING BACK TO NEAR AVERAGE FOR EARLY AUGUST.
52
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 6 AM MDT SUNDAY FOR THE FOLLOWING ZONES...
NMZ505-506-508-509-520.
&&
$$
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
301 AM MDT SUN AUG 3 2014
.SHORT TERM...TODAY THROUGH MONDAY NIGHT
ISSUED AT 259 AM MDT SUN AUG 3 2014
UPPER RIDGING CONTINUES ACROSS THE WESTERN CONUS WITH NW FLOW
CROSSING THE NRN PLAINS. WEAK UPPER WAVES CONTINUE TO ROUND THE TOP
OF THE RIDGE OVER THE NRN ROCKIES INTO THE NRN HIGH PLAINS. WV
IMAGERY SHOWS AN UPPER WAVE NOW CROSSING ERN MT BRINGING SHOWERS TO
SE MT. HRRR SHOWS THESE SHOWERS MAKING INTO FAR NE WY THRU NW SD
BEFORE 18Z SO HAVE ADDED SL CHC POPS THERE. MLCAPE FORECAST TO BE
500-1000 J/KG AGAIN TODAY...BUT BETTER LL SHEAR DEVELOPS LATE
AFTN/EVNG AS SFC LOW DEVELOPS JUST NW OF THE CWA. COULD SEE ISOLATED
STRONG STORMS OR PERHAPS A SVR STORM OR TWO.
WRN CONUS RIDGE BREAKS DOWN MONDAY AS UPPER LOW SLIDES INTO GREAT
BASIN. MONSOONAL STORMS WILL DEVELOP ACROSS WY AND BLKHLS...THEN
CROSS INTO THE CWA PLAINS THROUGH THE EVNG. MLCAPE OF 500-1000 AGAIN
EXPECTED...BUT THIS TIME WITH WEAKER AVAILABLE SHEAR. SEVERE STORMS
ARE NOT EXPECTED MON/MON NIGHT.
&&
.LONG TERM...TUESDAY THROUGH SATURDAY
ISSUED AT 259 AM MDT SUN AUG 3 2014
ACTIVE SW FLOW WILL DEVELOP BY TUESDAY...WITH DAILY CHANCE FOR
SHRA/TS THROUGH MOST OF THE WEEK...AS THE NE PAC NEGATIVE HEIGHT
ANOMALY SUPPORTS NUMEROUS LOW AMPLITUDE IMPULSES INTO THE FLOW AND
THE WESTERN RIDGE BREAKS DOWN. MOST ACTIVITY IS EXPECTED TO A HAVE
A STRONG DIURNAL COMPONENT...SUPPORTING THE HIGHEST CHANCES FOR
PRECIP IN THE AFTERNOON PERIODS...AND ESP OVER THE BLACK HILLS
GIVEN OROGRAPHIC INFLUENCES. GENERAL WSW FLOW WILL PERSIST INTO
THE WEEKEND WITH NO NOTED HIGH LATITUDE BLOCKING FAVORED IN MEAN
MODEL AND ENSEMBLE SOLUTIONS UNTIL EARLY NEXT WEEK WHEN THE
EASTERN NOAM UPPER TROUGH MAY MAKE A RETURN.
CARRIED AT LEAST A SLIGHT CHANCE POP MENTION THROUGH THE
PERIOD...RETAINING HIGHER NUMBERS TUESDAY THROUGH WED GIVEN
CONSISTENT SIGNALS FOR ADVECTING IMPULSES WITH APPRECIABLE LL
MOISTURE/WEAK CAPPING/AND A STALLED FRONTAL BOUNDARY OVER THE
REGION. RETAINED HIGHEST NUMBERS OVER THE BLACK HILLS...ESP TUE AND
WED. GENERAL WEAK 0-8 KM FLOW WITH PW VALUES IN EXCESS OF 1 INCH
MOST PLACES WILL SUPPORT AN INCREASED CHANCE FOR HEAVY
RAINFALL...ESP IN THE NORTHERN BLACK HILLS. SOME STRONG TO SEVERE
STORMS CANNOT BE RULED OUT IN THE PERIOD GIVEN POTENTIAL INCREASE IN
MID LEVEL FLOW AND POTENTIAL LL MOISTURE...ESP EARLY IN THE PERIOD.
TEMPERATURES ARE EXPECTED TO BE ON THE COOL SIDE OF SEASONAL NORMS
THROUGH MOST OF THE WEEK. LL EASTERLY FLOW/INCREASED CHANCES FOR
RAIN/AND INCREASED CLOUD COVER ARE ALL EXPECTED TO SUPPORT COOLER
TEMPS. HAVE CONTINUED TO NUDGE TEMPS DOWN TUES GIVEN MODEL/MOS
TRENDS. WARMER WEATHER LOOKS TO RETURN BY THE END OF THE WEEK AS BL
DRYING OCCURS UNDER HEIGHT RISES AND THERMAL RIDGING.
&&
.AVIATION...FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT
ISSUED AT 259 AM MDT SUN AUG 3 2014
VFR CONDITIONS EXPECTED THROUGH MORNING. SCT-ISOLATED SHRA/TSTMS
EXPECTED TO DEVELOP SUNDAY AFTN...ESPECIALLY OVER THE
BLKHLS...WITH LCL MVFR VSBY. ISOLD SHRA/TS WILL LINGER THROUGH
MUCH OF SUNDAY NIGHT...ESP ACROSS NW SD.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
SHORT TERM...13
LONG TERM...JC
AVIATION...JC
AREA FORECAST DISCUSSION
NWS SEATTLE WA
1008 PM PDT SAT AUG 2 2014
.SYNOPSIS...A WEAK DISTURBANCE ALOFT WILL KEEP THE AIR MASS UNSTABLE
ENOUGH FOR A RISK OF THUNDERSTORMS OVER MAINLY THE CASCADES THROUGH
SUNDAY. HIGH PRESSURE ALOFT WILL PREVAIL OVER THE REGION MONDAY AND
TUESDAY FOR DRY AND STABLE CONDITIONS.
&&
.SHORT TERM...
THERE WAS A SOUTHWEST TO NORTHEAST LINE OF TOWERING CUMULUS OVER
THE PUGET SOUND REGION AT THIS TIME. SHOWERS WERE FALLING FROM THE
FAR NORTH END OF THIS LINE IN SOUTHWEST SNOHOMISH COUNTY.
INTERESTINGLY...THE RUC DID SHOW A BAND OF SHOWERS OVER THE PUGET
SOUND REGION BUT EARLIER THAN OBSERVED. WILL UPDATE THE FORECAST
TO ADD SHOWERS TO THE PUGET SOUND REGION FOR TONIGHT. CANNOT
COMPLETELY RULE OUT TSTMS EITHER.
THE SURFACE ONSHORE PRESSURE GRADIENT WAS TIGHTER THAN LAST
NIGHT...HENCE STRATUS AND FOG HAS MADE IT AS FAR EAST AS THE LOWER
CHEHALIS RIVER VALLEY. THERE ALSO APPEARED TO BE STRATUS AND/OR FOG
OVER THE WATERS OF THE STRAIT OF JUAN DE FUCA. THE INTERIOR
LOWLANDS SHOULD SHOULD SEE SOME STRATUS SUNDAY MORNING. IT LOOKS
LIKE THE NAM MOS GUIDANCE PROBABLY HAS A BETTER HANDLE ON THE LOW
CLOUDS.
THE AIR MASS WILL BE GENERALLY STABLE ON SUNDAY WITH WEAK RIDGING
OVER WESTERN WA. THUNDERSTORMS WILL BE LIMITED TO THE NORTH
CASCADES ALONG THE CREST AS ANOTHER WEAK DISTURBANCE TRACKS ACROSS
SOUTHERN BRITISH COLUMBIA.
THE RIDGE WILL STRENGTHEN ON MONDAY FOR MORE DRY AND STABLE WEATHER.
TEMPS WILL BE A FEW DEGREES WARMER WITH HIGHS IN THE MID 80S IN THE
INTERIOR. ONSHORE FLOW WILL CONTINUE FOR COOLER AND CLOUDIER WEATHER
ALONG THE COAST. THE RIDGE WILL START TO EXIT ON TUE BUT WE ARE
STILL LOOKING FOR DRY AND WARM WEATHER. NO MAJOR CHANGES FROM THE
PREVIOUS FORECAST. 33/05
.LONG TERM FROM THE PREV DISCUSSION...
LONG TERM MODELS SHOWED THE UPPER LEVEL FLOW TURNING ZONAL BY
MIDWEEK AS THE STRONG UPPER RIDGE SHIFTS TO THE MIDWEST. A WEAK
FRONT WILL MOVE ACROSS WESTERN WA ON WEDNESDAY BUT THIS SYSTEM
LOOKS DRY. HOWEVER...WILL SEE AN INCREASE IN LOW LEVEL ONSHORE
FLOW THAT WILL LIKELY INCREASE THE COVERAGE OF MARINE STRATUS.
THIS WILL ALSO KEEP TEMPS CLOSER TO NORMAL. THE PATTERN WILL
REMAIN THE SAME THROUGH THE WEEKEND. WILL STICK WITH THE TREND OF
MORNING LOW CLOUDS WITH AFTERNOON SUN BREAKS. ANOTHER RIDGE MAY
BUILD OVER THE PAC NW EARLY NEXT WEEK FOR SLIGHTLY WARMER WEATHER.
33
&&
.AVIATION...FLOW ALOFT OVER WESTERN WASHINGTON IS SOUTHWESTERLY WITH
AN UPPER RIDGE CENTERED OVER THE ROCKIES. AT THE SURFACE HIGH
PRESSURE WILL REMAIN OFFSHORE WITH LOWER PRESSURE INLAND.
IFR STRATUS ALONG THE COAST WILL SPREAD INLAND LATE TONIGHT BUT WILL
LIKELY STOP AROUND THE WEST SHORES OF PUGET SOUND SUNDAY MORNING.
SKIES ARE MOSTLY CLEAR AWAY FROM THE STRATUS. ISOLATED THUNDERSTORMS
WILL CONTINUE OVER THE CASCADES THIS EVENING.
KSEA...MOSTLY CLEAR. COASTAL STRATUS SPREADING INLAND SUNDAY MORNING
IS EXPECTED TO STOP A LITTLE SHORT OF THE TERMINAL. NORTHWEST WIND
4-8 KNOTS BECOMING LIGHT SOUTHERLY AFTER MIDNIGHT. SCHNEIDER
&&
.MARINE...HIGH PRESSURE WILL REMAIN OFFSHORE WITH LOWER PRESSURE
INLAND FOR THE NEXT SEVERAL DAYS. SMALL CRAFT ADVISORY WEST WINDS
ARE POSSIBLE EACH AFTERNOON AND EVENING IN THE STRAIT OF JUAN DE
FUCA. AT THIS POINT MODELS POINT TO MONDAY EVENING AS HAVING THE
STRONGEST ONSHORE GRADIENTS. GALES ARE POSSIBLE IN THE STRAIT MONDAY
EVENING. SCHNEIDER
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...RED FLAG WARNING IN EFFECT TIL 11 PM TONIGHT FOR THE EAST
PORTION OF THE NORTH CASCADES NATIONAL PARK/LAKE CHELAN
NATIONAL RECREATIONAL AREA.
PZ...SMALL CRAFT ADVISORY IN EFFECT FOR THE COASTAL WATERS FROM
CAPE FLATTERY TO CAPE SHOALWATER FROM 10 NM TO OUT TO 60 NM
AND CENTRAL/EASTERN STRAIT OF JUAN DE FUCA.
&&
$$
WWW.WEATHER.GOV/SEATTLE
FOR THE GRAPHICAL AFD...VISIT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
AREA FORECAST DISCUSSION
NWS SEATTLE WA
930 PM PDT SAT AUG 2 2014
.SYNOPSIS...A WEAK DISTURBANCE ALOFT WILL KEEP THE AIR MASS
UNSTABLE ENOUGH FOR A RISK OF THUNDERSTORMS OVER MAINLY THE
CASCADES THROUGH SUNDAY. HIGH PRESSURE ALOFT WILL PREVAIL OVER THE
REGION MONDAY AND TUESDAY FOR DRY AND STABLE CONDITIONS.
&&
.SHORT TERM...
THERE WAS A SOUTHWEST TO NORTHEAST LINE OF TOWERING CUMULUS OVER
THE PUGET SOUND REGION AT THIS TIME. SHOWERS WERE FALLING FROM THE
FAR NORTH END OF THIS LINE IN SOUTHWEST SNOHOMISH COUNTY.
INTERESTINGLY...THE RUC DID SHOW A BAND OF SHOWERS OVER THE PUGET
SOUND REGION BUT EARLIER THAN OBSERVED. WILL UPDATE THE FORECAST
TO ADD SHOWERS TO THE PUGET SOUND REGION FOR TONIGHT. CANNOT
COMPLETELY RULE OUT TSTMS EITHER.
THE SURFACE ONSHORE PRESSURE GRADIENT WAS TIGHTER THAN LAST
NIGHT...HENCE STRATUS AND FOG HAS MADE IT AS FAR EAST AS THE LOWER
CHEHALIS RIVER VALLEY. THERE ALSO APPEARED TO BE STRATUS AND/OR FOG
OVER THE WATERS OF THE STRAIT OF JUAN DE FUCA. THE INTERIOR
LOWLANDS SHOULD SHOULD SEE SOME STRATUS SUNDAY MORNING. IT LOOKS
LIKE THE NAM MOS GUIDANCE PROBABLY HAS A BETTER HANDLE ON THE LOW
CLOUDS.
THE AIR MASS WILL BE GENERALLY STABLE ON SUNDAY WITH WEAK RIDGING
OVER WESTERN WA. THUNDERSTORMS WILL BE LIMITED TO THE NORTH
CASCADES ALONG THE CREST AS ANOTHER WEAK DISTURBANCE TRACKS ACROSS
SOUTHERN BRITISH COLUMBIA.
THE RIDGE WILL STRENGTHEN ON MONDAY FOR MORE DRY AND STABLE WEATHER.
TEMPS WILL BE A FEW DEGREES WARMER WITH HIGHS IN THE MID 80S IN THE
INTERIOR. ONSHORE FLOW WILL CONTINUE FOR COOLER AND CLOUDIER WEATHER
ALONG THE COAST. THE RIDGE WILL START TO EXIT ON TUE BUT WE ARE
STILL LOOKING FOR DRY AND WARM WEATHER. NO MAJOR CHANGES FROM THE
PREVIOUS FORECAST. 33
.LONG TERM FROM THE PREV DISCUSSION...
LONG TERM MODELS SHOWED THE UPPER LEVEL FLOW TURNING ZONAL BY
MIDWEEK AS THE STRONG UPPER RIDGE SHIFTS TO THE MIDWEST. A WEAK
FRONT WILL MOVE ACROSS WESTERN WA ON WEDNESDAY BUT THIS SYSTEM
LOOKS DRY. HOWEVER...WILL SEE AN INCREASE IN LOW LEVEL ONSHORE
FLOW THAT WILL LIKELY INCREASE THE COVERAGE OF MARINE STRATUS.
THIS WILL ALSO KEEP TEMPS CLOSER TO NORMAL. THE PATTERN WILL
REMAIN THE SAME THROUGH THE WEEKEND. WILL STICK WITH THE TREND OF
MORNING LOW CLOUDS WITH AFTERNOON SUN BREAKS. ANOTHER RIDGE MAY
BUILD OVER THE PAC NW EARLY NEXT WEEK FOR SLIGHTLY WARMER WEATHER.
33
&&
.AVIATION...FLOW ALOFT OVER WESTERN WASHINGTON IS SOUTHWESTERLY WITH
AN UPPER RIDGE CENTERED OVER THE ROCKIES. AT THE SURFACE HIGH
PRESSURE WILL REMAIN OFFSHORE WITH LOWER PRESSURE INLAND.
IFR STRATUS ALONG THE COAST WILL SPREAD INLAND LATE TONIGHT BUT WILL
LIKELY STOP AROUND THE WEST SHORES OF PUGET SOUND SUNDAY MORNING.
SKIES ARE MOSTLY CLEAR AWAY FROM THE STRATUS. ISOLATED THUNDERSTORMS
WILL CONTINUE OVER THE CASCADES THIS EVENING.
KSEA...MOSTLY CLEAR. COASTAL STRATUS SPREADING INLAND SUNDAY MORNING
IS EXPECTED TO STOP A LITTLE SHORT OF THE TERMINAL. NORTHWEST WIND
4-8 KNOTS BECOMING LIGHT SOUTHERLY AFTER MIDNIGHT. SCHNEIDER
&&
.MARINE...HIGH PRESSURE WILL REMAIN OFFSHORE WITH LOWER PRESSURE
INLAND FOR THE NEXT SEVERAL DAYS. SMALL CRAFT ADVISORY WEST WINDS
ARE POSSIBLE EACH AFTERNOON AND EVENING IN THE STRAIT OF JUAN DE
FUCA. AT THIS POINT MODELS POINT TO MONDAY EVENING AS HAVING THE
STRONGEST ONSHORE GRADIENTS. GALES ARE POSSIBLE IN THE STRAIT MONDAY
EVENING. SCHNEIDER
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...RED FLAG WARNING IN EFFECT TIL 11 PM TONIGHT FOR THE EAST
PORTION OF THE NORTH CASCADES NATIONAL PARK/LAKE CHELAN
NATIONAL RECREATIONAL AREA.
PZ...SMALL CRAFT ADVISORY IN EFFECT FOR THE COASTAL WATERS FROM
CAPE FLATTERY TO CAPE SHOALWATER FROM 10 NM TO OUT TO 60 NM
AND CENTRAL/EASTERN STRAIT OF JUAN DE FUCA.
&&
$$
WWW.WEATHER.GOV/SEATTLE
FOR THE GRAPHICAL AFD...VISIT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
855 AM MST SUN AUG 3 2014
&&
.SYNOPSIS...
EXPECT LESS CLOUDINESS THIS MORNING BEFORE THUNDERSTORM ACTIVITY
BEGINS TO DEVELOP IN THE AFTERNOON AS AN UPPER LOW CONTINUES TO
AFFECT THE REGION TODAY. FOR THE LOWER DESERTS...BEST CHANCES FOR
SHOWERS AND THUNDERSTORMS WILL BE OVER SOUTHEAST CALIFORNIA AND
PORTIONS OF SOUTHWEST ARIZONA. STORM CHANCES TREND DOWN MONDAY AS
THE LOW SHIFTS NORTHWARD AND WEAKENS. DRY SOUTHWESTERLY FLOW WILL
LIMIT STORM CHANCES TO EASTERN ARIZONA TUESDAY AND WEDNESDAY.
ANTICIPATE A GRADUAL RETURN OF STORM CHANCES FROM EAST TO WEST
DURING THE LATTER HALF OF THE WEEK.
&&
.DISCUSSION...
DRIER AIR ALOFT SPREADING IN FROM THE SOUTH BEHIND THE VORT LOBE
THAT PRODUCED STORMS OVER SOUTH-CENTRAL AZ HAVE PRETTY MUCH CLEARED
SKIES OVER MOST OF OUR CWA THIS MORNING...WITH JUST SOME LINGERING
CLOUDINESS CLOSER TO THE PARENT UPPER LOW CENTER OVER SE CA. THESE
CLEAR SKIES...COMBINED WITH ABUNDANT LOW-LEVEL MOISTURE...AND
ANOTHER WEAK VORT LOBE/JET MAX WILL LIKELY TRIGGER ANOTHER ROUND OF
TS ACTIVITY TODAY ACROSS SOUTH-CENTRAL AND SOUTHWEST AZ...WITH EVEN
BETTER CHANCES FOR TSTMS ACROSS SE CA THIS AFTERNOON AS THE MAIN
UPPER LOW MOVES NORTHWARD OVER SAN DIEGO COUNTY. GIVEN THE FACT THE
THE LATEST HRRR CONTINUES TO INDICATE TS DEVELOPMENT OVER WESTERN
MARICOPA AND YUMA COUNTIES EARLY THIS AFTERNOON JUST AHEAD OF THE
VORT LOBE...HAVE RAISED POPS WELL INTO THE CHANCE RANGE IN THE
18Z-00Z TIME FRAME ACROSS THAT REGION. THE MAIN THREAT FROM THIS
STORMS WILL BE STRONG WINDS AND BRIEF HEAVY DOWNPOURS...SINCE THEY
WILL TEND TO BE FASTER MOVING THEN THE STORMS WE SAW
YESTERDAY...WITH DECENT UPPER-LEVEL SHEAR ENHANCING TS DOWNBURSTS.
OTHER THAN THIS INCREASE IN POPS...INHERITED GRIDS ARE HOLDING UP
WELL.
&&
.PREVIOUS DISCUSSION...
TODAY...
UPPER LOW CENTERED NEAR ENSENADA THIS MORNING. SOUTHWESTERLY FLOW
ALOFT FURTHER SOUTH OVER BAJA IS SPREADING SOMEWHAT DRIER AIR INTO
ARIZONA SUCH THAT SKIES ARE CLEARING FROM THE SOUTH. THIS TREND WILL
ENABLE BETTER SURFACE HEATING TO OCCUR TODAY COMPARED TO YESTERDAY.
PROGGED CAPE VARIES CONSIDERABLY FROM ONE MODEL TO ANOTHER BUT THE
GFS AND NAM BOTH SHOW ROUGHLY 500-750 J/KG OF RELATIVELY SKINNY CAPE
OVER MUCH OF OUR FORECAST AREA. NOT SURPRISING SINCE MID LEVELS DONT
COOL MUCH. WITH DEEP SOUTHERLY FLOW...PIMA COUNTY WILL NEED TO BE
ACTIVE FOR THE SOUTH-CENTRAL ARIZONA DESERTS TO HAVE MUCH ACTIVITY.
NEARBY HIGHER TERRAIN WILL HAVE A BETTER OPPORTUNITY.
YESTERDAY...THE LOWER DESERTS OF SOUTHWEST ARIZONA AND ESPECIALLY
FAR SOUTHEAST CALIFORNIA WERE NOT VERY ACTIVE DUE TO STABLE BOUNDARY
LAYERS. TODAY MAY BE THE REVERSE. FOR ONE...THERE WILL BE LESS
CLOUDINESS WHICH WILL HELP THE BOUNDARY LAYER TO DESTABILIZE.
ALSO...THERE IS ANOTHER VORT LOBE ASSOCIATED WITH THE UPPER LOW THAT
IS PROGGED TO MOVE THROUGH TODAY AND PROVIDE SOME MODEST DYNAMICAL
FORCING. THIS WILL MAKE CONDITIONS MORE RESPONSIVE TO OUTFLOWS FROM
STORMS THAT DEVELOP OVER HIGHER TERRAIN AREAS SUCH AS FAR NORTHERN
BAJA AND SAN DIEGO COUNTY. AS A RESULT...THE HI RES MODELS GENERALLY
SHOW WESTERN PORTIONS OF THE FORECAST AREA BEING QUITE A BIT MORE
ACTIVE THAN EASTERN PORTIONS THIS AFTERNOON...EXCEPT FOR SOUTHERN
GILA COUNTY. FORECASTS REFLECT THIS AND IN FACT POPS WERE RAISED
OVER SOUTHEAST CALIFORNIA AND PORTIONS OF SOUTHWEST ARIZONA. A
LITTLE BIT OF VERTICAL WIND SHEAR AND MORE DCAPE WILL IMPROVE THE
CAPABILITY OF THE STORMS TO LAST LONGER AND PRODUCE STRONGER
DOWNDRAFTS. THE STRONGEST STORMS WILL HAVE THE POTENTIAL TO PRODUCE
BOTH VERY HEAVY RAIN AND DAMAGING WINDS.
MONDAY...
THE UPPER LOW CONTINUES MOVING NORTHWARD AND WEAKENS WITH TIME. ONE
LAST WAVE IS PROGGED TO TRACK ACROSS SOUTHEAST CALIFORNIA AND INTO
ARIZONA MONDAY BUT IT WEAKENS IN THE PROCESS. MEANWHILE...DRIER AIR
FILTERS INTO THE AREA. THUS POPS FOR MONDAY TREND DOWN...ESPECIALLY
OVER SOUTHEAST CALIFORNIA.
TUESDAY THROUGH SATURDAY...
DRY SOUTHWEST FLOW ALOFT WILL LEAD TO FURTHER DECLINE OF STORM
CHANCES WITH ONLY VERY SLIGHT CHANCES OVER THE HIGHER TERRAIN EAST
OF PHOENIX TUESDAY AND WEDNESDAY. FOR THE LATTER HALF OF THE
WEEK...BOTH GFS AND ECMWF DEPICT A MOIST ADVECTION TREND AND THUS AN
EAST TO WEST TREND OF SLIGHT CHANCE POPS OVER THE FORECAST
AREA...STOPPING SHORT OF THE LOWER COLORADO RIVER VALLEY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...
SKIES WILL REMAIN MOSTLY CLEAR THROUGH MUCH OF THE MORNING HOURS
BEFORE SCATTERED CU DEVELOPS AROUND NOON. WIND DIRECTIONS WILL SHIFT
TO A SOUTHERLY DIRECTION BY THE AFTERNOON AND GENERALLY STAY MOSTLY
SOUTH TO SOUTHWESTERLY UNTIL STORM OUTFLOWS AFFECT THE AREA.
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED FROM
LATE AFTERNOON THROUGH MID EVENING AND MAY IMPACT AREA TERMINALS FOR
A BRIEF TIME. THERE WILL BE THE POTENTIAL FOR STRONG GUSTY OUTFLOW
WINDS TODAY AS DRIER AIR AND STRONGER WINDS ALOFT MOVE INTO SOUTHERN
ARIZONA BY THIS AFTERNOON.
SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA......KIPL...AND KBLH...
UPPER LEVEL LOW OVER THE NORTHERN BAJA INTO FAR SOUTHERN CALIFORNIA
COAST WILL CONTINUE TO SUPPORT ISOLATED SHOWER ACTIVITY THROUGH THE
MORNING HOURS. EXPECTING SOME ISOLATED TO SCATTERED THUNDERSTORM
DEVELOPMENT AFTER 21Z...AND HAVE FAIRLY HIGH CONFIDENCE OF AFFECTING
AREA TERMINALS AT LEAST FOR A BRIEF TIME LATE THIS AFTERNOON. STRONG
GUSTY WINDS IN AND AROUND THUNDERSTORMS WILL BE THE MAIN THREAT. THE
UPPER LOW WILL PULL OUT OF THE AREA THIS EVENING LEAVING CLEARING
SKIES AND WEST TO SOUTHWESTERLY WINDS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
A DRY START TO THE FORECAST PERIOD IS EXPECTED WITH ONLY SLIGHT
CHANCES OF STORMS CONFINED TO HIGHER TERRAIN AREAS NORTH AND EAST OF
PHOENIX. THIS DRY AIR WILL LIKELY LAST THROUGH THURSDAY AND
POTENTIALLY LONGER...RESULTING IN AFTERNOON MINIMUM HUMIDITY
VALUES IN THE TEENS. A GRADUAL INCREASE IN MOISTURE SHOULD BEGIN
EITHER FRIDAY OR SATURDAY ALLOWING FOR A CHANCE OF STORMS INTO THE
SOUTH-CENTRAL ARIZONA DESERTS. HIGH TEMPERATURES WILL BE RIGHT
AROUND NORMAL FOR THE ENTIRE PERIOD.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...PERCHA
PREVIOUS DISCUSSION...AJ
AVIATION....KUHLMAN
FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
306 AM PDT SUN AUG 3 2014
.SYNOPSIS...
MONSOONAL MOISTURE WILL CONTINUE TO SURGE NORTH...BRINGING AT LEAST
A SLIGHT CHANCE OF SHOWERS/THUNDERSTORMS TO MUCH OF THE AREA THROUGH
THE AFTERNOON HOURS. THUNDERSTORM ACTIVITY WILL SHIFT TO THE HIGHER
ELEVATIONS LATE TONIGHT INTO EARLY MONDAY. OTHERWISE...NEAR NORMAL
DAYTIME HIGH TEMPERATURE WILL BE PRESENT OVER THE REGION THROUGH THE
END OF NEXT WEEK WITH A SLIGHT CHANCE OF THUNDERSTORMS OVER THE
SIERRA CREST EACH AFTERNOON.
&&
.DISCUSSION...AN UPPER LOW IN SOUTHERN CALIFORNIA IS MOVING
QUICKLY NORTHWARD...BRINGING ABUNDANT MOISTURE AND INSTABILITY TO
THE AREA. HANFORD RADAR IS ALREADY DETECTING RAIN SHOWERS
EXTENDING INTO NORTHERN KERN COUNTY THIS MORNING...AS A
SIGNIFICANT MONSOONAL SURGE MAKES ITS WAY NORTHWEST INTO THE AREA.
IN FACT...BY 2 AM...BAKERSFIELD HAD PICKED UP A TRACE OF
RAIN...SETTING A NEW RAINFALL RECORD FOR THE DAY. IT HAD NEVER
RAINED IN BAKERSFIELD ON AUGUST 3RD ACCORDING TO THE RECORD
ARCHIVES.
THUNDERSTORM ACTIVITY HAS MAINLY BEEN EAST OF THE SIERRA CREST
OVERNIGHT...HOWEVER...THERE WAS AT LEAST 1 STRIKE IN FAR EASTERN
KERN CO AROUND 2 AM. THUNDERSTORM ACTIVITY IS FORECAST TO INCREASE
INTO THE MORNING HOURS...AS MU CAPE VALUES INCREASE OVER NOT ONLY
THE HIGHER ELEVATIONS...BUT OVER THE SOUTHERN HALF OF THE VALLEY
AS WELL.
THE THUNDERSTORM ACTIVITY IS LIKELY TO PEAK LATER THIS MORNING INTO
THE EARLY AFTERNOON HOURS...WITH MU CAPE VALUES PEAKING OVER THE
SIERRA CREST...WITH VALUES BETWEEN 300 AND 500 J/KG. STORMS THAT DO
FORM OVER THE CREST WILL MOVE SOUTHWEST INTO THE EASTERN HALF OF
THE VALLEY...WITH THE NAM INDICATING MU CAPE VALUES BETWEEN 100 TO
200 J/KG...SUFFICIENT ENOUGH FOR STRIKES OVER THE VALLEY. IN
ADDITION...THE LAST FEW RUNS OF THE HRRR HAVE BEEN VERY CONSISTENT
WITH RAIN/THUNDERSTORM ACTIVITY SPREADING INTO NORTHERN FRESNO
COUNTY BY 10 AM. FORECASTER CONFIDENCE MEDIUM TO HIGH WITH REGARDS
TO THUNDERSTORM ACTIVITY.
ADDITIONALLY...PWAT VALUES ARE FORECAST TO INCREASE TO 1.5 INCHES
FROM FRESNO COUNTY SOUTHWARD...RESULTING IN FLASH FLOODING
CONCERNS...MAINLY FOR THE KERN COUNTY DESERT AND MOUNTAIN.
FORECAST MODELS ARE IN GOOD AGREEMENT THAT AREAS IN KERN COUNTY
COULD EASILY SEE BETWEEN A QUARTER AND A THIRD OF AN INCH OF RAIN
BY THIS AFTERNOON...WITH LOCALLY HIGHER AMOUNTS TO ONE-HALF INCH.
WITH RECENT FIRES/BURN SCARS IN MIND...A FLASH FLOOD WATCH WAS
ISSUED FOR THESE AREAS AND IS VALID FROM THIS MORNING THROUGH
EARLY MONDAY MORNING. FORECASTER CONFIDENCE MEDIUM.
ONE LAST INTERESTING THING ABOUT THE FORECAST FOR TODAY...MUCH OF
THE AREA HAS LIKELY HIT THEIR FORECAST HIGH TEMPERATURE. FORECAST
HIGH TEMPERATURES FOR THE VALLEY WILL GENERALLY RANGE FROM THE
UPPER 80S TO MID 90S...BETWEEN 10 AND 15 DEGREES COOLER COMPARED
TO YESTERDAY.
THUNDERSTORM ACTIVITY IS FORECAST TO SHIFT NORTH THROUGH THE
DAY...WITH ACTIVITY MAINLY CONFINED TO THE SIERRA CREST LATE
TONIGHT INTO EARLY MONDAY MORNING AS THE UPPER LOW MOVES NORTHEAST
INTO CENTRAL CALIFORNIA.
AFTER MONDAY MORNING...THE SHORT AND MEDIUM RANGE MODELS ARE IN
GOOD AGREEMENT THAT MONSOONAL MOISTURE WILL SHIFT QUICKLY TO THE
EAST...WITH THUNDERSTORM ACTIVITY CONFINED TO THE SIERRA CREST
EACH AFTERNOON AND EVENING. FORECASTER CONFIDENCE MEDIUM.
TEMPERATURES ARE FORECAST TO REBOUND MONDAY INTO THE REST OF THE
WORK WEEK...WITH VALLEY TEMPERATURES IN THE MID TO UPPER
90S...NEAR NORMAL FOR THE BEGINNING OF AUGUST. BY FRIDAY...A FEW
VALLEY LOCATIONS MAY WARM TO THE CENTURY MARK.
&&
.AVIATION...
SCATTERED THUNDERSTORMS CAN BE EXPECTED OVER THE MOUNTAINS
THROUGH TONIGHT WITH LOCAL MVFR VISIBILITIES AND CEILINGS.
ISOLATED THUNDERSTORMS WILL OCCUR IN THE KERN COUNTY DESERT
THROUGH EARLY THIS EVENING. THERE IS A SLIGHT CHANCE OF
THUNDERSTORMS OVER THE KERN COUNTY PORTION OF THE SAN JOAQUIN
VALLEY AND THE EAST SIDE OF THE SAN JOAQUIN VALLEY AND ADJACENT
FOOTHILLS UNTIL 06Z MONDAY. VFR CONDITIONS CAN BE EXPECTED
ELSEWHERE ACROSS THE CENTRAL CALIFORNIA INTERIOR DURING THE
NEXT 24 HOURS.
&&
.AIR QUALITY ISSUES...
ON SUNDAY AUGUST 3 2014... UNHEALTHY IN MADERA COUNTY. UNHEALTHY
FOR SENSITIVE GROUPS IN FRESNO COUNTY AND SEQUOIA NATIONAL PARK
AND FOREST.
FURTHER INFORMATION IS AVAILABLE AT VALLEYAIR.ORG
&&
.CERTAINTY...
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.
&&
.CLIMATE...
RECORDS
SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR
KFAT 08-03 110:1946 80:1976 78:1901 55:1953
KFAT 08-04 110:1889 83:1976 82:1901 53:1956
KFAT 08-05 110:1895 83:1957 79:1998 51:1950
KBFL 08-03 112:1938 81:1953 81:1974 53:1912
KBFL 08-04 109:1901 85:1953 82:1961 53:1903
KBFL 08-05 110:1998 85:1957 80:1998 52:1899
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH LATE TONIGHT CAZ095-098-099.
&&
$$
PUBLIC...RILEY
AVN/FW...DURFEE
SYNOPSIS...RILEY
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS MIAMI FL
955 AM EDT SUN AUG 3 2014
.UPDATE...
THE LATEST FORECAST PACKAGE HAS BEEN UPDATED TO REFLECT THE LATEST
OBSERVATIONS AND TRENDS AROUND THE AREA THIS MORNING AND TO
INCREASE THE RAINFALL CHANCES FOR TODAY THROUGH MONDAY. THE
MORNING SURFACE ANALYSIS SHOWED A TROUGH OF LOW PRESSURE EXTENDING
NORTHWARD ACROSS THE AREA AND NUMEROUS SHOWERS AND STORMS
DEVELOPING ALONG A CONVERGENT BOUNDARY OFF OF THE SE FLORIDA COAST
ACROSS THE ATLANTIC WATERS. THE LATEST HRRR CYCLE SHOWED THIS
COASTAL ACTIVITY SHIFTING WESTWARD THIS AFTERNOON THROUGH THE
EARLY EVENING PERIOD, ESPECIALLY ALONG THE EAST COAST AS THE
TROUGH SHIFTS WEST AND THE LOW-LEVEL FLOW VEERS TO THE SW.
PROVIDED THE EXTENSIVE CLOUD COVERAGE ALONG THE EAST COAST...IT
MAY TAKE LONGER INTO THE AFTERNOON BEFORE THE EAST COAST SEA
BREEZE DEVELOPS. THIS COULD DELAY THIS COASTAL ACTIVITY FROM
SHIFTING WESTWARD WELL INTO THE EARLY AFTERNOON HOURS. IF THE HRRR
ENDS UP VERIFYING, LOCALIZED FLOODING CAN`T BE RULED OUT LATER
TODAY OVER THE EAST COAST AND METRO AREAS CONSIDERING THE RECENT
ACTIVITY AND THE SATURATED GROUNDS. 85/AG
&&
.PREV DISCUSSION... /ISSUED 813 AM EDT SUN AUG 3 2014/
AVIATION...
AN AREA OF LOW PRESSURE ACROSS THE BAHAMAS CONTINUES TO SPREAD
DEEP MOISTURE ACROSS THE ATLANTIC WATERS AND INTO SOUTH FLORIDA.
THIS WILL RESULT IN NUMEROUS SHOWERS AND A FEW THUNDERSTORMS
AFFECTING THE EAST COAST SITES THROUGH THE DAY. PREVAILING WIND
DIRECTION WILL BE A CHALLENGE AS IT WILL BE DEPENDENT ON THE EXACT
TRACK OF THE LOW AS IT PROGRESSES NORTHWARD. FOR NOW...PREVAILED
MAINLY SOUTHEAST WINDS THROUGH THE AFTERNOON FROM KFLL NORTHWARD
WITH MORE SOUTHWESTERLY FROM KOPF SOUTHWARD. CONFIDENCE IS LOW
HOWEVER AS MODELS DIFFER ON THE EXACT TRACK OF THE LOW.
PREV DISCUSSION... /ISSUED 415 AM EDT SUN AUG 3 2014/
DISCUSSION...
DEEP MOISTURE HAS ARRIVED WITH 2"+ PWATS IN PLACE ACROSS SOUTH
FLORIDA ASSOCIATED WITH AN AREA OF LOW PRESSURE WHICH HAS BEEN
MOVING OUR WAY FROM THE BAHAMAS. FOR SEVERAL RUNS...MODELS HAVE BEEN
ADVERTISING NUMEROUS THUNDERSTORMS UNDERNEATH THIS SURFACE LOW
TODAY. MAY NEED TO BE WARY OF VERY SLOW MOVING STORMS AND STORM
COLLISIONS/MERGERS DUE TO LIGHT WINDS...LEADING TO POSSIBLE WATER
PROBLEMS OVER THE NEXT FEW DAYS. HRRR AND HI RES MODELS INDICATE
STORMS FIRST EITHER MOVE ONSHORE OR DEVELOP ALONG THE ATLANTIC
COAST...THEN CRAWL TO THE INTERIOR LATE DAY. THE WEAK LOW THEN
MOVES NORTH SUNDAY NIGHT AND MERGES WITH THE STATIONARY BOUNDARY
WHICH HAS BEEN DRAPED THROUGH THE SOUTHEAST FOR SEVERAL DAYS.
MODEL SOUNDINGS INDICATE THAT THE 2"+ PWATS REMAIN THROUGH
TUESDAY...ALTHOUGH THIS MAY BE SLIGHTLY OVERDONE CONSIDERING THE
MEAN RH IN SOME OF THE MODEL MASS FIELDS WHICH SHOWS A BIT OF A
DRYING TREND.
SURFACE WINDS WILL BECOME SW TO W MONDAY AND TUESDAY WITH THE
SURFACE LOW ACROSS NORTH FLORIDA. A MORNING GULF COAST IS EXPECTED
WITH FOCUS THEN SHIFTING TO THE INTERIOR AND ATLANTIC COAST LATER
IN THE DAY.
ALTHOUGH THE STATIONARY BOUNDARY WILL WASH OUT ACROSS THE
SOUTHEAST...A SUBTLE WEAKNESS/TROUGH WILL REMAIN ALONG THE EAST
COAST INTO THE MIDDLE OF NEXT WEEK. THIS WILL DELAY THE ARRIVAL OF
UPPER RIDGING/RISING HEIGHTS/SUBSIDENCE ACROSS SOUTH FLORIDA
UNTIL LATE NEXT WORK WEEK OR NEXT WEEKEND. THUS...WEDNESDAY MAY BE
A WETTER DAY THAN PREVIOUS FORECASTS HAVE SUGGESTED.
MARINE...
TROPICAL STORM BERTHA IS FORECAST TO REMAIN WELL EAST OF THE SOUTH
FLORIDA MARINE AREAS AS IT TURNS NORTH EAST OF THE BAHAMAS LATE
SUNDAY NIGHT THROUGH MONDAY. WINDS ARE FORECAST TO SHIFT TO THE
SOUTHWEST THROUGH THE EARLY PORTION OF THE WEEK FROM 5 KTS TO 15
KTS...THEN BECOMING VARIABLE AROUND 5 KTS BY THE END OF THE WEEK.
SCATTERED SHOWERS AND STORMS COULD LEAD TO GUSTY WINDS AND LOCALLY
CHOPPIER CONDITIONS EACH DAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 91 79 90 77 / 80 30 70 30
FORT LAUDERDALE 90 79 91 80 / 80 30 70 40
MIAMI 90 78 90 79 / 80 30 70 40
NAPLES 92 77 88 77 / 60 30 50 60
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...84/AK
LONG TERM....21/KM
AREA FORECAST DISCUSSION
NWS MIAMI FL
813 AM EDT SUN AUG 3 2014
.AVIATION...
AN AREA OF LOW PRESSURE ACROSS THE BAHAMAS CONTINUES TO SPREAD
DEEP MOISTURE ACROSS THE ATLANTIC WATERS AND INTO SOUTH FLORIDA.
THIS WILL RESULT IN NUMEROUS SHOWERS AND A FEW THUNDERSTORMS
AFFECTING THE EAST COAST SITES THROUGH THE DAY. PREVAILING WIND
DIRECTION WILL BE A CHALLENGE AS IT WILL BE DEPENDENT ON THE EXACT
TRACK OF THE LOW AS IT PROGRESSES NORTHWARD. FOR NOW...PREVAILED
MAINLY SOUTHEAST WINDS THROUGH THE AFTERNOON FROM KFLL NORTHWARD
WITH MORE SOUTHWESTERLY FROM KOPF SOUTHWARD. CONFIDENCE IS LOW
HOWEVER AS MODELS DIFFER ON THE EXACT TRACK OF THE LOW.
&&
.PREV DISCUSSION... /ISSUED 415 AM EDT SUN AUG 3 2014/
DISCUSSION...
DEEP MOISTURE HAS ARRIVED WITH 2"+ PWATS IN PLACE ACROSS SOUTH
FLORIDA ASSOCIATED WITH AN AREA OF LOW PRESSURE WHICH HAS BEEN
MOVING OUR WAY FROM THE BAHAMAS. FOR SEVERAL RUNS...MODELS HAVE BEEN
ADVERTISING NUMEROUS THUNDERSTORMS UNDERNEATH THIS SURFACE LOW
TODAY. MAY NEED TO BE WARY OF VERY SLOW MOVING STORMS AND STORM
COLLISIONS/MERGERS DUE TO LIGHT WINDS...LEADING TO POSSIBLE WATER
PROBLEMS OVER THE NEXT FEW DAYS. HRRR AND HI RES MODELS INDICATE
STORMS FIRST EITHER MOVE ONSHORE OR DEVELOP ALONG THE ATLANTIC
COAST...THEN CRAWL TO THE INTERIOR LATE DAY. THE WEAK LOW THEN
MOVES NORTH SUNDAY NIGHT AND MERGES WITH THE STATIONARY BOUNDARY
WHICH HAS BEEN DRAPED THROUGH THE SOUTHEAST FOR SEVERAL DAYS.
MODEL SOUNDINGS INDICATE THAT THE 2"+ PWATS REMAIN THROUGH
TUESDAY...ALTHOUGH THIS MAY BE SLIGHTLY OVERDONE CONSIDERING THE
MEAN RH IN SOME OF THE MODEL MASS FIELDS WHICH SHOWS A BIT OF A
DRYING TREND.
SURFACE WINDS WILL BECOME SW TO W MONDAY AND TUESDAY WITH THE
SURFACE LOW ACROSS NORTH FLORIDA. A MORNING GULF COAST IS EXPECTED
WITH FOCUS THEN SHIFTING TO THE INTERIOR AND ATLANTIC COAST LATER
IN THE DAY.
ALTHOUGH THE STATIONARY BOUNDARY WILL WASH OUT ACROSS THE
SOUTHEAST...A SUBTLE WEAKNESS/TROUGH WILL REMAIN ALONG THE EAST
COAST INTO THE MIDDLE OF NEXT WEEK. THIS WILL DELAY THE ARRIVAL OF
UPPER RIDGING/RISING HEIGHTS/SUBSIDENCE ACROSS SOUTH FLORIDA
UNTIL LATE NEXT WORK WEEK OR NEXT WEEKEND. THUS...WEDNESDAY MAY BE
A WETTER DAY THAN PREVIOUS FORECASTS HAVE SUGGESTED.
MARINE...
TROPICAL STORM BERTHA IS FORECAST TO REMAIN WELL EAST OF THE SOUTH
FLORIDA MARINE AREAS AS IT TURNS NORTH EAST OF THE BAHAMAS LATE
SUNDAY NIGHT THROUGH MONDAY. WINDS ARE FORECAST TO SHIFT TO THE
SOUTHWEST THROUGH THE EARLY PORTION OF THE WEEK FROM 5 KTS TO 15
KTS...THEN BECOMING VARIABLE AROUND 5 KTS BY THE END OF THE WEEK.
SCATTERED SHOWERS AND STORMS COULD LEAD TO GUSTY WINDS AND LOCALLY
CHOPPIER CONDITIONS EACH DAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 91 79 90 77 / 70 30 40 30
FORT LAUDERDALE 90 79 91 80 / 70 30 40 40
MIAMI 90 78 90 79 / 70 30 40 40
NAPLES 92 77 88 77 / 60 30 60 60
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
857 AM EDT SUN AUG 3 2014
.SYNOPSIS...
WEAK LOW PRESSURE WILL TRACK NORTHEAST ALONG A STALLED FRONTAL
BOUNDARY OFF THE NEW ENGLAND COAST TODAY. THE FRONTAL BOUNDARY
WILL DRIFT OFF TO THE EAST TONIGHT AND MONDAY. A SLOW MOVING COLD
FRONT WILL APPROACH FROM THE NORTHWEST ON TUESDAY AND WILL
GRADUALLY PUSH EAST OF THE REGION ON WEDNESDAY. A TROUGH OF LOW
PRESSURE WILL LINGER OVER THE AREA ON THURSDAY AND FRIDAY. HIGH
PRESSURE WILL BUILD IN FROM THE WEST OVER THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
.UPDATE...
A FEW MINOR CHANGES TO THE FORECAST THIS MORNING INCLUDING
TAILORING SOUTHERN POPS CLOSER TO WHAT MESOSCALE MODELS HAVE OVER
THE NEXT FEW HOURS. HRRR HAS A GOOD HANDLE ON PRECIPITATION THIS
MORNING WHILE NAM IS A LITTLE FAST. INCREASED POPS OVER HIGHER
TERRAIN THIS AFTERNOON. ISOLATED THUNDERSTORMS WILL POSE A BRIEF
THREAT ONCE AGAIN THIS AFTERNOON.
&&
PREVIOUS DISCUSSION...LOW PRESSURE TRACKING NORTHEAST ALONG A
STALLED FRONTAL BOUNDARY OFF THE NEW ENGLAND COAST WILL KEEP
HIGH CLOUDS ACROSS THE REGION FOR MUCH OF TODAY. EXPECT PRECIP TO
ONCE AGAIN REMAIN OFFSHORE.
EXPECT ENOUGH INSTABILITY TO DEVELOP ACROSS NORTHERN ZONES TO
KICK OFF A FEW SHOWERS AND THUNDERSTORMS IN THE MOUNTAINS. HIGH
TEMPS TODAY WILL BE ABOUT THE SAME AS SATURDAY WITH LOWER TO MID
70S ALONG THE COAST AND MID 70S TO NEAR 80 INLAND.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
VARIABLE HIGH CLOUDS AND AREAS OF FOG OVERNIGHT AS STALLED FRONTAL
BOUNDARY DRIFTS OFF TO THE EAST. AFTER A FEW EVENING SHOWERS OR
THUNDERSTORMS IN THE NORTH EXPECT ACTIVITY TO DIE OFF. LOW TEMPS
WILL GENERALLY BE IN THE MID TO UPPER 50S ACROSS THE REGION.
ENTIRE FORECAST AREA WILL SEE A CHANCE OF SHOWERS OR THUNDERSTORMS
ON MONDAY. EXPECT PARTLY TO MOSTLY SUNNY SKIES WITH HIGHS IN THE
MID 70S TO MID 80S.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
AN UPPER LVL TROF MOVING IN FROM THE WEST BRINGS A SFC COLD FNT
TOWARD THE REGION MONDAY NGT AND TUESDAY THEN THE FNT SLOWLY CROSSES
THE REGION TUESDAY NGT AND WEDNESDAY. AT THIS TIME TROPICAL STORM
BERTHA TRACKS TO THE NE STAYING WELL OUT TO SEA AND HAVING NO IMPACT
ON OUR WX. THE FNT WILL RESULT IN MORE SHRA/TSTMS FOR THE FCST
AREA...ESPECIALLY ON WEDNESDAY AS THE INTENSIFYING UPPER LEVEL
FEATURE GETS CLOSER. THE FNT MOVES JUST OFFSHORE WEDNESDAY NGT
CONTINUING THE CHC OF SHRA/TSTMS. ON THURSDAY A SECOND FNT MOVES
THRU AS A VIGOROUS UPPER LEVEL SHORT WAVE TROF BECOMES A CUTOFF LOW
AND MOVES OVER THE REGION. THIS UPPER LVL SYSTEM WILL REMAIN OVER
THE REGION THRU FRIDAY ALONG WITH A SERIES OF WEAK SFC TROFS MOVING
THRU THUS GIVING US A CHC OF SHRA/TSTMS. ON SATURDAY THE UPPER LEVEL
SYSTEM SLOWLY MOVES OFF TO THE E AS AN UPPER LEVEL RIDGE BUILDS IN
BEHIND IT ALLOWING A SFC HIGH PRESSURE SYSTEM TO ALSO BUILD IN FROM
THE W. THIS SHOULD GIVE US IMPROVING WX ON SATURDAY.
USED A BLEND OF VARIOUS MODELS...HPC GUIDANCE...PREVIOUS FCST FOR
PERSISTENCE AND CLIMATOLOGY FOR THE LONG TERM FCST.
&&
.AVIATION /13Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...AREAS OF MVFR/IFR CEILINGS AND VSBY IN PATCHY MORNING
FOG... IMPROVING TO VFR. DITTO FOR TONIGHT AND MONDAY.
LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...UNSETTLED WX PATTERN
WITH A RISK OF SHRA/TSTMS EACH DAY WHICH MAY CREATE MVFR/IFR
CONDITIONS...MORE SO IN THE AFTERNOON AND EVENING HOURS.
&&
.MARINE...
SHORT TERM...NO FLAGS.
LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...TROPICAL STORM BERTHA
MOVES TO THE NE STAYING WELL OUT TO SEA. HOWEVER THIS STORM MAY
GENERATE SWELLS THAT IMPACT OUR COASTAL WATERS IN THE TUESDAY THRU
WEDNESDAY TIME FRAME. OTHERWISE THE SFC WEATHER PATTERN HAS WEAK
FEATURES DOMINATING THRU THE LONG TERM FCST PERIOD RESULTING IN
WINDS AND SEAS BELOW SCA LEVELS.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
UPDATE...HANES
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1101 AM EDT SUN AUG 3 2014
LATEST UPDATE...
UPDATE/MARINE
.SYNOPSIS...
ISSUED AT 330 AM EDT SUN AUG 3 2014
A WEAK HIGH PRESSURE RIDGE WILL BRING FAIR WEATHER TODAY WITH
SEASONABLY WARM TEMPERATURES. A WEAK COLD FRONT WILL BRING
SCATTERED SHOWERS AND THUNDERSTORMS MONDAY INTO MONDAY EVENING.
A FEW SHOWERS AND STORMS WILL LINGER MAINLY NEAR TO SOUTH OF
INTERSTATE 96 TUESDAY BEFORE DRY WEATHER RETURNS WEDNESDAY THROUGH
THE REMAINDER OF THE WEEK. TEMPERATURES WILL AVERAGE RATHER CLOSE
TO NORMAL THROUGH THE UPCOMING WEEK.
&&
.UPDATE...
ISSUED AT 1046 AM EDT SUN AUG 3 2014
BUMPED UP AFTERNOON TEMPERATURES A DEGREE OR TWO...OTHERWISE NO
CHANGES ON MORNING UPDATE.
LOOKING AT TOMORROW...INITIAL THINKING IS THAT THERE WILL BE A
GOOD BIT OF EVENING SHOWER / THUNDERSTORM ACTIVITY SLOWLY WORKING
NORTH TO SOUTH AHEAD OF DEVELOPING COLD FRONT. EXPECTING A FEW
STRONG STORMS WITH HEAVY RAIN AND MICROBURST POTENTIAL ASSOCIATED
WITH POORLY ORGANIZED MULITCELLS SUPPORTED BY ML CAPE AROUND 1000
J/KG AND WEAK DEEP LAYER SHEAR OF < 20 KTS. SOME MOISTURE POOLING
ALONG FRONTAL BOUNDARY WITH WEAK MOIST FLUX CONVERGENCE AND MODEST UPPER
DIVERGENCE AHEAD OF DIGGING SHORT WAVE WILL PROVIDE FORCING. THAT SHORTWAVE
IS NOW PUSHING THROUGH SOUTHERN ALBERTA AND N MO AND LOOKS PRETTY
GOOD ON WATER VAPOR IMAGERY.
UPDATE ISSUED AT 604 AM EDT SUN AUG 3 2014
I HAVE UPDATED OUR GRIDS AND ZONE FORECAST TO INCLUDE AREAS OF
DENSE FOG NORTH AND EAST OF US-131 AND I-96 TILL ABOUT 9 AM. THE
RAP MODEL SHOWS THE LOW LEVEL FLOW HAS BEEN OFF LAKE HURON INTO
CENTRAL LOWER MICHIGAN AIMED DIRECTLY INTO THE WHERE DENSE FOG HAS
DEVELOPED. THE RAP MODEL VISIBILITY FORECAST...WHICH IS DOING
GREAT ON THE AREA OF DENSE FOG CURRENTLY (05 AM) SHOWS IT TOTALLY
MIXING OUT BY 9 AM. THAT MAKES SENSE AS THERE IS LITTLE IN THE WAY
OF CLOUDS OVER THE FOG AND IT IS SHALLOW FOG TOO. AFTER COORDINATING
WITH APX ON THE ISSUE WE DECIDED NOT TO ISSUE A DENSE FOG ADVISORY
BUT JUST TO PUT AREAS OF DENSE FOG IN THE GRIDS AND CALL THAT
GOOD.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 330 AM EDT SUN AUG 3 2014
OUR PRIMARY SHORT TERM FORECAST CONCERNS INVOLVE DETERMINING
POTENTIAL FOR CONVECTION MONDAY THROUGH TUESDAY.
A WEAK COLD FRONT WILL BRING SCATTERED SHOWERS AND THUNDERSTORMS
MONDAY INTO MONDAY NIGHT. THE BEST CHANCE FOR STORMS MONDAY WILL BE
NEAR TO MAINLY EAST OF US-131 WHERE THERE WILL BE LESS OF A
STABILIZING INFLUENCE FROM LAKE MI.
SB CAPE VALUES WILL POTENTIALLY REACH AROUND 2000 J/KG OVER OUR
EASTERN FCST AREA AS SUGGESTED BY LATEST 00Z GFS AND ECMWF
GUIDANCE. HOWEVER ML CAPE VALUES MAY ONLY REACH AROUND 750 J/KG
OVER OUR SE FCST AREA ACCORDING TO LATEST SREF GUIDANCE.
SEVERE WEATHER IS NOT ANTICIPATED DUE TO RELATIVELY WEAK FORCING
FROM THE WEAK COLD FRONT... WEAK 0-6 KM BULK SHEAR VALUES OF ONLY
AROUND 15-20 KTS AND LACK OF STRONGER INSTABILITY.
A CONSENSUS OF LATEST SHORT RANGE GUIDANCE SUGGESTS SCATTERED
SHOWERS AND PERHAPS A FEW STORMS WILL LINGER MONDAY NIGHT AND THEN
INTO TUESDAY MAINLY NEAR TO SOUTH OF I-96. HOWEVER WEAKER INSTABILITY
IS ANTICIPATED TUESDAY AND IT WILL BE MORE CONFINED TO THE AREA
NEAR TO SOUTH OF I-96.
A WEAK HIGH PRESSURE RIDGE WILL BRING FAIR AND SEASONABLY WARM WX
TODAY WITH MAX TEMPS REACHING THE LOWER TO MIDDLE 80S... EXCEPT A
LITTLE COOLER RIGHT ALONG THE LAKE MI SHORELINE DUE TO SW FLOW AND
THE LAKE BREEZE OFF OF RELATIVELY COLD LAKE WATERS. CANNOT
COMPLETELY RULE OUT POTENTIAL FOR AN ISOLATED SHOWER NEAR OR EAST OF
US-131 THIS AFTERNOON BUT THERE IS NOT ENOUGH POTENTIAL IN IT TO
WARRANT INCLUSION IN THE FCST.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 335 AM EDT SUN AUG 3 2014
IT WOULD NOT BE OUT OF THE QUESTION THERE COULD BE A LINGERING
SHOWER OR THUNDERSTORMS INTO EARLY WEDNESDAY BEHIND THE COLD FRONT
THE PRIMARY MESSAGE FOR THIS FORECAST TIME PERIOD WEATHERWISE IS
DRY. TEMPERATURES WILL ONCE AGAIN FALL BELOW NORMAL DURING THE MID
WEEK PERIOD. BY THE WEEKEND EXPECT TEMPERATURES TO RISE TO ABOVE
NORMAL LEVELS... BUT STILL I DO NOT SEE HIGHS IN THE 90S... MORE
LIKE MID 80S HIGHS BY SATURDAY.
AS I HAVE BEEN SAYING THE PAST FEW NIGHTS... THE EASTERN TROUGH
FORECAST BY THE ECMWF WILL BE STRONG ENOUGH TO BRING THE POLAR JET
SOUTH OF MICHIGAN ONCE AGAIN BY WEDNESDAY. WE THEN GET SHORTWAVE
RIDGING TO BUILD INTO THE AREA BY SATURDAY. THAT WILL BRING THE
WARMER TEMPERATURES TO THE AREA. UNLIKE THIS LAST DEEP UPPER TROUGH
WHEN THE POLAR JET WAS WELL SOUTH OF MICHIGAN FOR SEVERAL DAYS...
THIS TIME IT WILL BE ONLY FOR A DAY. THAT MEANS THERE WILL NOT BE
ENOUGH COLD AIR ALOFT FOR AFTERNOON CONVECTION. HENCE THE DRY
FORECAST FOR WEDNESDAY AFTERNOON THROUGH SATURDAY.
ONE THING TO WATCH FOR... TUESDAY NIGHT WE HAVE THE JET EXIT REGION
OVER SOUTHWEST MICHIGAN. THAT MAY BE ENOUGH TO SUPPORT SOME
THUNDERSTORM ACTIVITY. HOWEVER AT THIS POINT IT LOOKS LIKE TO MUCH
DRY AIR AT MID LEVELS. EVEN SO I HAVE LOW CHANCE POPS FOR THE
SOUTHERN SECTIONS OF THE CWA TUESDAY NIGHT INTO WEDNESDAY MORNING
JUST I CASE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 742 AM EDT SUN AUG 3 2014
ANY AREAS OF FOG WILL LIFT OUT QUICKLY THIS MORNING WITH STRONG
AUGUST SUNSHINE AND THE FOG BEING OF A SHALLOW NATURE. THEN VFR
CONDITIONS WILL PREVAIL THROUGH THE DAY TIME INTO THIS EVENING.
DURING THE EARLY MORNING HOURS OF MONDAY...I EXPECT AND AREA OF
SHOWERS AND THUNDERSTORMS TO MOVE SOUTH SOUTHEAST AS THE WARMER AND
MORE MOIST AIR ARRIVES AT MID AND HIGH LEVELS. THE CHANCES OF
SEEING SUCH A STORM IS BEST CLOSER TO THE LAKE SHORE. I EXPECT
MVFR FOG MONDAY MORNING AS HIGHER DEW POINT AIR MOVES INTO THE
AREA FROM THE SOUTH.
&&
.MARINE...
ISSUED AT 1046 AM EDT SUN AUG 3 2014
CONTINUE TO SEE SOME FOG...MAY INCREASE IN COVERAGE AND DENSITY
OVERNIGHT TONIGHT AS AIRMASS MOISTENS FURTHER AHEAD OF NEXT COLD
FRONT. FOG MAY CONTINUE TO BE A THREAT UNTIL TUE AFTERNOON WHEN
DRIER AIR WORKS INTO THE AREA. NO WIND OR WAVE ISSUES IN THE
FORESEABLE FUTURE.
&&
.HYDROLOGY...
ISSUED AT 306 PM EDT SAT AUG 2 2014
NO HYDRO ISSUES DUE TO A FAIRLY DRY WEATHER PATTERN. BRIEF PERIODS
OF LOCALLY HEAVY RAINFALL ARE POSSIBLE THIS EVENING IN SCATTERED
THUNDERSTORMS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...COBB
SYNOPSIS...LAURENS
SHORT TERM...LAURENS
LONG TERM...WDM
AVIATION...WDM
HYDROLOGY...93
MARINE...COBB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1010 AM EDT SUN AUG 3 2014
.UPDATE...
ISSUED AT 1009 AM EDT SUN AUG 3 2014
NO MAJOR CHANGES TO THE FORECAST PLANNED. LATEST SFC AND OBJECTIVE
DATA SUGGESTS THAT THE SFC FRONT AT 14Z EXTENDS FROM WAWA ONTARIO
THROUGH MARQUETTE TO IRONWOOD. THE FRONT LIKELY SURGED ACROSS THE
COLD LAKE AND WILL NOW SLOW DOWN DUE TO THE HEATING OF THE LANDMASS
OVER UPPER MI. LATEST OBSERVATIONS ALSO SHOW POOLING OF HIGHER SFC
DEW POINTS ALONG THE FRONT WITH DWPTS IN THE LOWER 60S ACROSS NRN WI
AND SRN UPPER MI. WITH THAT SAID...THE EXPECTATION OF SHOWERS AND
THUNDERSTORMS DEVELOPING LATER THIS MORNING INTO THIS AFTERNOON
ALONG JUST INLAND OF LAKE SUPERIOR ACROSS THE EASTERN HALF OF THE
FORECAST AREA STILL SEEMS REASONABLE. THE CONVECTION BEARING HI RES
NWP ARE IN FAIRLY GOOD AGREEMENT IN THIS OCCURRING BY 18Z...WITH
BROKEN THUNDERSTORMS EXTENDING ALONG THE LAKE BREEZE BOUNDARIES FROM
NEGAUNEE THROUGH CHATHAM TO SENEY AND NEWBERRY. DESPITE FORECAST
MLCAPE VALUES OF 1000 J/KG...DUE TO RELATIVELY WEAK MID LEVEL LAPSE
RATES OF ONLY 6-6.25C/KM...IT SEEMS UNLIKELY THAT SEVERE WEATHER
WILL DEVELOP. HOWEVER...THE MODEL SOUNDINGS DO SUGGEST SOME DRYING
IN THE LOWER LEVELS WHICH MAY PERHAPS SUGGEST A MINOR WIND GUST
THREAT WITH ANY STORM. MOST LIKELY...ANY STRONGER STORM MAY SEE SOME
GUSTY WINDS OF 30-40 MPH AND SMALL HAIL DUE TO THE RELATIVELY LOW
WET BULB ZERO LEVELS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 351 AM EDT SUN AUG 3 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW NW FLOW OVER THE
UPR LKS BTWN TROF CENTERED OVER QUEBEC AND MEAN RDG OVER THE
ROCKIES. DESPITE SHARP MID LVL INVRN/VERY DRY MID LVLS SHOWN ON THE
00Z GRB RAOB ASSOCIATED WITH SHRTWV RDG PASSING THRU THE UPR LKS
THAT IS BRINGING MOCLR CONDITIONS TO UPR MI...THERE ARE SOME ISOLD
SHOWERS OVER WI AND FAR WRN UPR MI IN ADVANCE OF A SHRTWV DROPPING
SEWD THRU SRN MN. A STRONGER SHRTWV EMBEDDED IN THE NW FLOW ALF IS
MOVING ESEWD THRU NW ONTARIO...WITH ATTENDANT RATHER WEAK SFC-H85
COLD FNT MOVING INTO NRN MN. THERE WERE SOME SHOWERS/TS LAST EVNG
OVER FARN NRN MN/ADJOINING ONTARIO IN ADVANCE OF THIS FNT IN THE
FAIRLY MOIST ENVIRONMENT DEPICTED ON THE 00Z INL RAOB /00Z PWAT WAS
1.25 INCH OR ALMOST 150 PCT OF NORMAL AND KINX WAS 32/...BUT LOSS OF
DAYTIME HEATING...PASSAGE OF SHARPER FORCING TO THE N AND ABSENCE OF
SGNFT H85-7 MSTR INFLOW NECESSARY TO SUSTAIN NOCTURNAL CONVECTION
HAVE CAUSED THESE SHOWERS TO DIMINISH ALMOST ENTIRELY EARLY THIS
MRNG IN AN ENVIRONMENT WHERE MUCAPE IS 100-250 J/KG AT BEST.
MAIN FCST CONCERNS THRU TNGT ARE FOCUSED ON POPS ASSOCIATED WITH
APRCHG COLD FNT.
TODAY...SHRTWV OVER ONTARIO IS PROGGED TO CONTINUE ESEWD...WITH
ATTENDANT SFC COLD FNT ON A LINE THRU NW LK SUP AT 12Z THIS MRNG
FCST TO REACH THE SE CWA BY LATE THIS AFTN. WL CARRY ONLY ISOLD
SHOWERS THIS MRNG OVER THE NW CWA ASSOCIATED WITH THE FROPA GIVEN
PRESENT COVERAGE ALONG THE FNT AND PASSAGE OF SHARPER FORCING TO THE
N. BUT AS THE FNT/MID LVL COMMA TAIL MSTR RIBBON PRESSES TO THE SE
THIS AFTN IN THE PRESENCE OF DAYTIME HEATING...EXPECT THE SHOWER/TS
COVERAGE TO INCRS. INTERACTION BTWN THE FNT AND LK BREEZE BNDRYS
THAT WL SHARPEN THE LLVL CNVGC WL ALSO AID THE CONVECTION. BOTH THE
00Z NAM/LOCAL WRF-ARW MODELS INDICATE THE LI WL DROP AS LO AS -6 TO
-8C AS MUCAPES REACH ARND 2500 J/KG THIS AFTN OVER THE SCNTRL CWA...
JUSTIFYING THE GOING LIKELY POPS IN THE CURRENT FCST FOR THAT AREA
THIS AFTN. WITH SFC-6KM BULK SHEAR AS HI AS 30 KTS...THERE COULD BE
SOME STRONGER CELLS. WITH SFC TEMPS RISING TO 80-85 AHEAD OF THE FNT
RESULTING IN ADIABATIC LAPSE RATES IN THE PBL...GUSTY WINDS SHOULD
BE THE MAIN THREAT. BUT MARGINAL LAPSE RATES AND SHEAR INDICATE SVR
WX IS NOT LIKELY.
TNGT...ARRIVAL OF SOME DRYING ALF FOLLOWING THE FROPA AND LOSS OF
DAYTIME HEATING SHOULD RESULT IN LINGERING POPS OVER THE SE CWA
DIMINISHING THIS EVNG. BUT SINCE SEVERAL MODELS SHOW ANOTHER
WEAKER SHRTWV DROPPING SEWD IN THE NW FLOW ALF AND ASSOCIATED
DPVA/DEEP LYR QVECTOR CNVGC IMPACTING THE CWA OVERNGT...WL RETAIN
SOME LOWER CHC POPS MAINLY OVER THE SRN TIER CLOSER TO THE HIER
LINGERING PWAT AOA AN INCH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 351 AM EDT SUN AUG 3 2014
GENERALLY QUIET WEATHER EXPECTED THROUGH THE EXTENDED WITH DRY
WEATHER AND MODERATING TEMPERATURES EXPECTED. ISOLATED SHOWERS AND
THUNDERSTORMS ARE POSSIBLE NEAR THE WISCONSIN BORDER DURING THE DAY
MONDAY AS A SHORTWAVE PASSES THROUGH THE BROAD TROUGHING STILL IN
PLACE OVER MUCH OF THE EASTERN U.S. THE BETTER FORCING AN MOISTURE
IS EXPECTED TO REMAIN MAINLY SOUTH OF THE REGION AS THE VORT MAX
SWINGS THROUGH...HOWEVER...IT WILL BRUSH CLOSE ENOUGH TO THE U.P./WI
BORDER TO KEEP SLIGHT POPS IN THE FORECAST. ANOTHER SHORTWAVE IS
PROGGED TO ROTATE AROUND THE TROUGH TUESDAY
NIGHT...HOWEVER...CONDITIONS WILL REMAIN DRY AS THIS WILL SWING
THROUGH DURING THE COOLER OVERNIGHT HOURS WITH VERY LIMITED MOISTURE
AVAILABLE DURING THAT TIME.
THE REMAINDER OF THE EXTENDED...WEDNESDAY THROUGH SATURDAY WILL BE
DOMINATED BY BROAD SURFACE HIGH PRESSURE ALONG WITH UPPER LEVEL
500MB RIDGING SLIDING FROM THE WESTERN U.S. INTO THE CENTRAL U.S.
THIS WILL ALLOW TEMPERATURES TO WARM TO NEAR OR SLIGHTLY ABOVE
NORMAL BY THE END OF THE WORK WEEK AND INTO THE UPCOMING WEEKEND.
CONDITIONS WILL REMAIN DRY AS DRY AIR REMAINS IN PLACE ACROSS THE
GREAT LAKES REGION THROUGH THIS TIME PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 724 AM EDT SUN AUG 3 2014
EXPECT ANY LINGERING FOG AT IWD/SAW TO BURN OFF QUICKLY THIS MRNG. A
COLD FNT PUSHING ACRS UPR MI TDAY MAY BRING SOME -SHRA/TS TO MAINLY
SAW THIS AFTN. RIGHT NOW...IT APPEARS THE FROPA WL OCCUR TOO EARLY
AT IWD AND CMX TO ALLOW FOR ANY SHOWERS AT THOSE SITES. ALTHOUGH VFR
CONDITIONS WL PREDOMINATE TDAY AND THIS EVNG...LINGERING LLVL MSTR
BLO SOME MID LVL DRYING SHOULD ALLOW FOR MORE FOG FORMATION TNGT AS
WINDS WL BE LGT. IFR CONDITIONS ARE A GOOD POSSIBILITY...ESPECIALLY
AT CMX AND IWD...WHERE THE MID LVL DRYING WL BE MOST PRONOUNCED.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 351 AM EDT SUN AUG 3 2014
TYPICAL SUMMER TYPE FLOW REGIME/WEAK PRES GRADIENT WILL KEEP WINDS
UNDER 15 KT THROUGH MUCH OF THIS COMING WEEK. SOME PATCHY FOG IS
POSSIBLE INTO MON...ESPECIALLY IF RAIN FALLS TODAY. BUT ANY
WIDESPREAD DENSE FOG IS UNLIKELY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...MRD
SHORT TERM...KC
LONG TERM...KEC
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
742 AM EDT SUN AUG 3 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 330 AM EDT SUN AUG 3 2014
A WEAK HIGH PRESSURE RIDGE WILL BRING FAIR WEATHER TODAY WITH
SEASONABLY WARM TEMPERATURES. A WEAK COLD FRONT WILL BRING
SCATTERED SHOWERS AND THUNDERSTORMS MONDAY INTO MONDAY EVENING.
A FEW SHOWERS AND STORMS WILL LINGER MAINLY NEAR TO SOUTH OF
INTERSTATE 96 TUESDAY BEFORE DRY WEATHER RETURNS WEDNESDAY THROUGH
THE REMAINDER OF THE WEEK. TEMPERATURES WILL AVERAGE RATHER CLOSE
TO NORMAL THROUGH THE UPCOMING WEEK.
&&
.UPDATE...
ISSUED AT 604 AM EDT SUN AUG 3 2014
I HAVE UPDATED OUR GRIDS AND ZONE FORECAST TO INCLUDE AREAS OF
DENSE FOG NORTH AND EAST OF US-131 AND I-96 TILL ABOUT 9 AM. THE
RAP MODEL SHOWS THE LOW LEVEL FLOW HAS BEEN OFF LAKE HURON INTO
CENTRAL LOWER MICHIGAN AIMED DIRECTLY INTO THE WHERE DENSE FOG HAS
DEVELOPED. THE RAP MODEL VISIBILITY FORECAST...WHICH IS DOING
GREAT ON THE AREA OF DENSE FOG CURRENTLY (05 AM) SHOWS IT TOTALLY
MIXING OUT BY 9 AM. THAT MAKES SENSE AS THERE IS LITTLE IN THE WAY
OF CLOUDS OVER THE FOG AND IT IS SHALLOW FOG TOO. AFTER COORDINATING
WITH APX ON THE ISSUE WE DECIDED NOT TO ISSUE A DENSE FOG ADVISORY
BUT JUST TO PUT AREAS OF DENSE FOG IN THE GRIDS AND CALL THAT
GOOD.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 330 AM EDT SUN AUG 3 2014
OUR PRIMARY SHORT TERM FORECAST CONCERNS INVOLVE DETERMINING
POTENTIAL FOR CONVECTION MONDAY THROUGH TUESDAY.
A WEAK COLD FRONT WILL BRING SCATTERED SHOWERS AND THUNDERSTORMS
MONDAY INTO MONDAY NIGHT. THE BEST CHANCE FOR STORMS MONDAY WILL BE
NEAR TO MAINLY EAST OF US-131 WHERE THERE WILL BE LESS OF A
STABILIZING INFLUENCE FROM LAKE MI.
SB CAPE VALUES WILL POTENTIALLY REACH AROUND 2000 J/KG OVER OUR
EASTERN FCST AREA AS SUGGESTED BY LATEST 00Z GFS AND ECMWF
GUIDANCE. HOWEVER ML CAPE VALUES MAY ONLY REACH AROUND 750 J/KG
OVER OUR SE FCST AREA ACCORDING TO LATEST SREF GUIDANCE.
SEVERE WEATHER IS NOT ANTICIPATED DUE TO RELATIVELY WEAK FORCING
FROM THE WEAK COLD FRONT... WEAK 0-6 KM BULK SHEAR VALUES OF ONLY
AROUND 15-20 KTS AND LACK OF STRONGER INSTABILITY.
A CONSENSUS OF LATEST SHORT RANGE GUIDANCE SUGGESTS SCATTERED
SHOWERS AND PERHAPS A FEW STORMS WILL LINGER MONDAY NIGHT AND THEN
INTO TUESDAY MAINLY NEAR TO SOUTH OF I-96. HOWEVER WEAKER INSTABILITY
IS ANTICIPATED TUESDAY AND IT WILL BE MORE CONFINED TO THE AREA
NEAR TO SOUTH OF I-96.
A WEAK HIGH PRESSURE RIDGE WILL BRING FAIR AND SEASONABLY WARM WX
TODAY WITH MAX TEMPS REACHING THE LOWER TO MIDDLE 80S... EXCEPT A
LITTLE COOLER RIGHT ALONG THE LAKE MI SHORELINE DUE TO SW FLOW AND
THE LAKE BREEZE OFF OF RELATIVELY COLD LAKE WATERS. CANNOT
COMPLETELY RULE OUT POTENTIAL FOR AN ISOLATED SHOWER NEAR OR EAST OF
US-131 THIS AFTERNOON BUT THERE IS NOT ENOUGH POTENTIAL IN IT TO
WARRANT INCLUSION IN THE FCST.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 335 AM EDT SUN AUG 3 2014
IT WOULD NOT BE OUT OF THE QUESTION THERE COULD BE A LINGERING
SHOWER OR THUNDERSTORMS INTO EARLY WEDNESDAY BEHIND THE COLD FRONT
THE PRIMARY MESSAGE FOR THIS FORECAST TIME PERIOD WEATHERWISE IS
DRY. TEMPERATURES WILL ONCE AGAIN FALL BELOW NORMAL DURING THE MID
WEEK PERIOD. BY THE WEEKEND EXPECT TEMPERATURES TO RISE TO ABOVE
NORMAL LEVELS... BUT STILL I DO NOT SEE HIGHS IN THE 90S... MORE
LIKE MID 80S HIGHS BY SATURDAY.
AS I HAVE BEEN SAYING THE PAST FEW NIGHTS... THE EASTERN TROUGH
FORECAST BY THE ECMWF WILL BE STRONG ENOUGH TO BRING THE POLAR JET
SOUTH OF MICHIGAN ONCE AGAIN BY WEDNESDAY. WE THEN GET SHORTWAVE
RIDGING TO BUILD INTO THE AREA BY SATURDAY. THAT WILL BRING THE
WARMER TEMPERATURES TO THE AREA. UNLIKE THIS LAST DEEP UPPER TROUGH
WHEN THE POLAR JET WAS WELL SOUTH OF MICHIGAN FOR SEVERAL DAYS...
THIS TIME IT WILL BE ONLY FOR A DAY. THAT MEANS THERE WILL NOT BE
ENOUGH COLD AIR ALOFT FOR AFTERNOON CONVECTION. HENCE THE DRY
FORECAST FOR WEDNESDAY AFTERNOON THROUGH SATURDAY.
ONE THING TO WATCH FOR... TUESDAY NIGHT WE HAVE THE JET EXIT REGION
OVER SOUTHWEST MICHIGAN. THAT MAY BE ENOUGH TO SUPPORT SOME
THUNDERSTORM ACTIVITY. HOWEVER AT THIS POINT IT LOOKS LIKE TO MUCH
DRY AIR AT MID LEVELS. EVEN SO I HAVE LOW CHANCE POPS FOR THE
SOUTHERN SECTIONS OF THE CWA TUESDAY NIGHT INTO WEDNESDAY MORNING
JUST I CASE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 742 AM EDT SUN AUG 3 2014
ANY AREAS OF FOG WILL LIFT OUT QUICKLY THIS MORNING WITH STRONG
AUGUST SUNSHINE AND THE FOG BEING OF A SHALLOW NATURE. THEN VFR
CONDITIONS WILL PREVAIL THROUGH THE DAY TIME INTO THIS EVENING.
DURING THE EARLY MORNING HOURS OF MONDAY...I EXPECT AND AREA OF
SHOWERS AND THUNDERSTORMS TO MOVE SOUTH SOUTHEAST AS THE WARMER AND
MORE MOIST AIR ARRIVES AT MID AND HIGH LEVELS. THE CHANCES OF
SEEING SUCH A STORM IS BEST CLOSER TO THE LAKE SHORE. I EXPECT
MVFR FOG MONDAY MORNING AS HIGHER DEW POINT AIR MOVES INTO THE
AREA FROM THE SOUTH.
&&
.MARINE...
ISSUED AT 330 AM EDT SUN AUG 3 2014
A WEAK PRESSURE GRADIENT WILL CONTINUE TO RESULT IN FAIRLY MINIMAL
WIND AND WAVE ACTION THE NEXT COUPLE OF DAYS WITH WAVE HEIGHTS UNDER
TWO FEET. HOWEVER SOME PATCHY FOG THAT MAY BE DENSE AT TIMES IS
ANTICIPATED THAT WILL CONTINUE TO POSE A HAZARD TO MARINERS DUE TO
RELATIVELY COLD LAKE WATERS AND HIGHER DEW POINT AIR JUST ABOVE
THE LAKE SURFACE.
&&
.HYDROLOGY...
ISSUED AT 306 PM EDT SAT AUG 2 2014
NO HYDRO ISSUES DUE TO A FAIRLY DRY WEATHER PATTERN. BRIEF PERIODS
OF LOCALLY HEAVY RAINFALL ARE POSSIBLE THIS EVENING IN SCATTERED
THUNDERSTORMS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...LAURENS
SHORT TERM...LAURENS
LONG TERM...WDM
AVIATION...WDM
HYDROLOGY...93
MARINE...LAURENS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
725 AM EDT SUN AUG 3 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 351 AM EDT SUN AUG 3 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW NW FLOW OVER THE
UPR LKS BTWN TROF CENTERED OVER QUEBEC AND MEAN RDG OVER THE
ROCKIES. DESPITE SHARP MID LVL INVRN/VERY DRY MID LVLS SHOWN ON THE
00Z GRB RAOB ASSOCIATED WITH SHRTWV RDG PASSING THRU THE UPR LKS
THAT IS BRINGING MOCLR CONDITIONS TO UPR MI...THERE ARE SOME ISOLD
SHOWERS OVER WI AND FAR WRN UPR MI IN ADVANCE OF A SHRTWV DROPPING
SEWD THRU SRN MN. A STRONGER SHRTWV EMBEDDED IN THE NW FLOW ALF IS
MOVING ESEWD THRU NW ONTARIO...WITH ATTENDANT RATHER WEAK SFC-H85
COLD FNT MOVING INTO NRN MN. THERE WERE SOME SHOWERS/TS LAST EVNG
OVER FARN NRN MN/ADJOINING ONTARIO IN ADVANCE OF THIS FNT IN THE
FAIRLY MOIST ENVIRONMENT DEPICTED ON THE 00Z INL RAOB /00Z PWAT WAS
1.25 INCH OR ALMOST 150 PCT OF NORMAL AND KINX WAS 32/...BUT LOSS OF
DAYTIME HEATING...PASSAGE OF SHARPER FORCING TO THE N AND ABSENCE OF
SGNFT H85-7 MSTR INFLOW NECESSARY TO SUSTAIN NOCTURNAL CONVECTION
HAVE CAUSED THESE SHOWERS TO DIMINISH ALMOST ENTIRELY EARLY THIS
MRNG IN AN ENVIRONMENT WHERE MUCAPE IS 100-250 J/KG AT BEST.
MAIN FCST CONCERNS THRU TNGT ARE FOCUSED ON POPS ASSOCIATED WITH
APRCHG COLD FNT.
TODAY...SHRTWV OVER ONTARIO IS PROGGED TO CONTINUE ESEWD...WITH
ATTENDANT SFC COLD FNT ON A LINE THRU NW LK SUP AT 12Z THIS MRNG
FCST TO REACH THE SE CWA BY LATE THIS AFTN. WL CARRY ONLY ISOLD
SHOWERS THIS MRNG OVER THE NW CWA ASSOCIATED WITH THE FROPA GIVEN
PRESENT COVERAGE ALONG THE FNT AND PASSAGE OF SHARPER FORCING TO THE
N. BUT AS THE FNT/MID LVL COMMA TAIL MSTR RIBBON PRESSES TO THE SE
THIS AFTN IN THE PRESENCE OF DAYTIME HEATING...EXPECT THE SHOWER/TS
COVERAGE TO INCRS. INTERACTION BTWN THE FNT AND LK BREEZE BNDRYS
THAT WL SHARPEN THE LLVL CNVGC WL ALSO AID THE CONVECTION. BOTH THE
00Z NAM/LOCAL WRF-ARW MODELS INDICATE THE LI WL DROP AS LO AS -6 TO
-8C AS MUCAPES REACH ARND 2500 J/KG THIS AFTN OVER THE SCNTRL CWA...
JUSTIFYING THE GOING LIKELY POPS IN THE CURRENT FCST FOR THAT AREA
THIS AFTN. WITH SFC-6KM BULK SHEAR AS HI AS 30 KTS...THERE COULD BE
SOME STRONGER CELLS. WITH SFC TEMPS RISING TO 80-85 AHEAD OF THE FNT
RESULTING IN ADIABATIC LAPSE RATES IN THE PBL...GUSTY WINDS SHOULD
BE THE MAIN THREAT. BUT MARGINAL LAPSE RATES AND SHEAR INDICATE SVR
WX IS NOT LIKELY.
TNGT...ARRIVAL OF SOME DRYING ALF FOLLOWING THE FROPA AND LOSS OF
DAYTIME HEATING SHOULD RESULT IN LINGERING POPS OVER THE SE CWA
DIMINISHING THIS EVNG. BUT SINCE SEVERAL MODELS SHOW ANOTHER
WEAKER SHRTWV DROPPING SEWD IN THE NW FLOW ALF AND ASSOCIATED
DPVA/DEEP LYR QVECTOR CNVGC IMPACTING THE CWA OVERNGT...WL RETAIN
SOME LOWER CHC POPS MAINLY OVER THE SRN TIER CLOSER TO THE HIER
LINGERING PWAT AOA AN INCH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 351 AM EDT SUN AUG 3 2014
GENERALLY QUIET WEATHER EXPECTED THROUGH THE EXTENDED WITH DRY
WEATHER AND MODERATING TEMPERATURES EXPECTED. ISOLATED SHOWERS AND
THUNDERSTORMS ARE POSSIBLE NEAR THE WISCONSIN BORDER DURING THE DAY
MONDAY AS A SHORTWAVE PASSES THROUGH THE BROAD TROUGHING STILL IN
PLACE OVER MUCH OF THE EASTERN U.S. THE BETTER FORCING AN MOISTURE
IS EXPECTED TO REMAIN MAINLY SOUTH OF THE REGION AS THE VORT MAX
SWINGS THROUGH...HOWEVER...IT WILL BRUSH CLOSE ENOUGH TO THE U.P./WI
BORDER TO KEEP SLIGHT POPS IN THE FORECAST. ANOTHER SHORTWAVE IS
PROGGED TO ROTATE AROUND THE TROUGH TUESDAY
NIGHT...HOWEVER...CONDITIONS WILL REMAIN DRY AS THIS WILL SWING
THROUGH DURING THE COOLER OVERNIGHT HOURS WITH VERY LIMITED MOISTURE
AVAILABLE DURING THAT TIME.
THE REMAINDER OF THE EXTENDED...WEDNESDAY THROUGH SATURDAY WILL BE
DOMINATED BY BROAD SURFACE HIGH PRESSURE ALONG WITH UPPER LEVEL
500MB RIDGING SLIDING FROM THE WESTERN U.S. INTO THE CENTRAL U.S.
THIS WILL ALLOW TEMPERATURES TO WARM TO NEAR OR SLIGHTLY ABOVE
NORMAL BY THE END OF THE WORK WEEK AND INTO THE UPCOMING WEEKEND.
CONDITIONS WILL REMAIN DRY AS DRY AIR REMAINS IN PLACE ACROSS THE
GREAT LAKES REGION THROUGH THIS TIME PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 724 AM EDT SUN AUG 3 2014
EXPECT ANY LINGERING FOG AT IWD/SAW TO BURN OFF QUICKLY THIS MRNG. A
COLD FNT PUSHING ACRS UPR MI TDAY MAY BRING SOME -SHRA/TS TO MAINLY
SAW THIS AFTN. RIGHT NOW...IT APPEARS THE FROPA WL OCCUR TOO EARLY
AT IWD AND CMX TO ALLOW FOR ANY SHOWERS AT THOSE SITES. ALTHOUGH VFR
CONDITIONS WL PREDOMINATE TDAY AND THIS EVNG...LINGERING LLVL MSTR
BLO SOME MID LVL DRYING SHOULD ALLOW FOR MORE FOG FORMATION TNGT AS
WINDS WL BE LGT. IFR CONDITIONS ARE A GOOD POSSIBILITY...ESPECIALLY
AT CMX AND IWD...WHERE THE MID LVL DRYING WL BE MOST PRONOUNCED.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 351 AM EDT SUN AUG 3 2014
TYPICAL SUMMER TYPE FLOW REGIME/WEAK PRES GRADIENT WILL KEEP WINDS
UNDER 15 KT THROUGH MUCH OF THIS COMING WEEK. SOME PATCHY FOG IS
POSSIBLE INTO MON...ESPECIALLY IF RAIN FALLS TODAY. BUT ANY
WIDESPREAD DENSE FOG IS UNLIKELY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KEC
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
604 AM EDT SUN AUG 3 2014
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 330 AM EDT SUN AUG 3 2014
A WEAK HIGH PRESSURE RIDGE WILL BRING FAIR WEATHER TODAY WITH
SEASONABLY WARM TEMPERATURES. A WEAK COLD FRONT WILL BRING
SCATTERED SHOWERS AND THUNDERSTORMS MONDAY INTO MONDAY EVENING.
A FEW SHOWERS AND STORMS WILL LINGER MAINLY NEAR TO SOUTH OF
INTERSTATE 96 TUESDAY BEFORE DRY WEATHER RETURNS WEDNESDAY THROUGH
THE REMAINDER OF THE WEEK. TEMPERATURES WILL AVERAGE RATHER CLOSE
TO NORMAL THROUGH THE UPCOMING WEEK.
&&
.UPDATE...
ISSUED AT 604 AM EDT SUN AUG 3 2014
I HAVE UPDATED OUR GRIDS AND ZONE FORECAST TO INCLUDE AREAS OF
DENSE FOG NORTH AND EAST OF US-131 AND I-96 TILL ABOUT 9 AM. THE
RAP MODEL SHOWS THE LOW LEVEL FLOW HAS BEEN OFF LAKE HURON INTO
CENTRAL LOWER MICHIGAN AIMED DIRECTLY INTO THE WHERE DENSE FOG HAS
DEVELOPED. THE RAP MODEL VISIBILITY FORECAST...WHICH IS DOING
GREAT ON THE AREA OF DENSE FOG CURRENTLY (05 AM) SHOWS IT TOTALLY
MIXING OUT BY 9 AM. THAT MAKES SENSE AS THERE IS LITTLE IN THE WAY
OF CLOUDS OVER THE FOG AND IT IS SHALLOW FOG TOO. AFTER COORDINATING
WITH APX ON THE ISSUE WE DECIDED NOT TO ISSUE A DENSE FOG ADVISORY
BUT JUST TO PUT AREAS OF DENSE FOG IN THE GRIDS AND CALL THAT
GOOD.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 330 AM EDT SUN AUG 3 2014
OUR PRIMARY SHORT TERM FORECAST CONCERNS INVOLVE DETERMINING
POTENTIAL FOR CONVECTION MONDAY THROUGH TUESDAY.
A WEAK COLD FRONT WILL BRING SCATTERED SHOWERS AND THUNDERSTORMS
MONDAY INTO MONDAY NIGHT. THE BEST CHANCE FOR STORMS MONDAY WILL BE
NEAR TO MAINLY EAST OF US-131 WHERE THERE WILL BE LESS OF A
STABILIZING INFLUENCE FROM LAKE MI.
SB CAPE VALUES WILL POTENTIALLY REACH AROUND 2000 J/KG OVER OUR
EASTERN FCST AREA AS SUGGESTED BY LATEST 00Z GFS AND ECMWF
GUIDANCE. HOWEVER ML CAPE VALUES MAY ONLY REACH AROUND 750 J/KG
OVER OUR SE FCST AREA ACCORDING TO LATEST SREF GUIDANCE.
SEVERE WEATHER IS NOT ANTICIPATED DUE TO RELATIVELY WEAK FORCING
FROM THE WEAK COLD FRONT... WEAK 0-6 KM BULK SHEAR VALUES OF ONLY
AROUND 15-20 KTS AND LACK OF STRONGER INSTABILITY.
A CONSENSUS OF LATEST SHORT RANGE GUIDANCE SUGGESTS SCATTERED
SHOWERS AND PERHAPS A FEW STORMS WILL LINGER MONDAY NIGHT AND THEN
INTO TUESDAY MAINLY NEAR TO SOUTH OF I-96. HOWEVER WEAKER INSTABILITY
IS ANTICIPATED TUESDAY AND IT WILL BE MORE CONFINED TO THE AREA
NEAR TO SOUTH OF I-96.
A WEAK HIGH PRESSURE RIDGE WILL BRING FAIR AND SEASONABLY WARM WX
TODAY WITH MAX TEMPS REACHING THE LOWER TO MIDDLE 80S... EXCEPT A
LITTLE COOLER RIGHT ALONG THE LAKE MI SHORELINE DUE TO SW FLOW AND
THE LAKE BREEZE OFF OF RELATIVELY COLD LAKE WATERS. CANNOT
COMPLETELY RULE OUT POTENTIAL FOR AN ISOLATED SHOWER NEAR OR EAST OF
US-131 THIS AFTERNOON BUT THERE IS NOT ENOUGH POTENTIAL IN IT TO
WARRANT INCLUSION IN THE FCST.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 335 AM EDT SUN AUG 3 2014
IT WOULD NOT BE OUT OF THE QUESTION THERE COULD BE A LINGERING
SHOWER OR THUNDERSTORMS INTO EARLY WEDNESDAY BEHIND THE COLD FRONT
THE PRIMARY MESSAGE FOR THIS FORECAST TIME PERIOD WEATHERWISE IS
DRY. TEMPERATURES WILL ONCE AGAIN FALL BELOW NORMAL DURING THE MID
WEEK PERIOD. BY THE WEEKEND EXPECT TEMPERATURES TO RISE TO ABOVE
NORMAL LEVELS... BUT STILL I DO NOT SEE HIGHS IN THE 90S... MORE
LIKE MID 80S HIGHS BY SATURDAY.
AS I HAVE BEEN SAYING THE PAST FEW NIGHTS... THE EASTERN TROUGH
FORECAST BY THE ECMWF WILL BE STRONG ENOUGH TO BRING THE POLAR JET
SOUTH OF MICHIGAN ONCE AGAIN BY WEDNESDAY. WE THEN GET SHORTWAVE
RIDGING TO BUILD INTO THE AREA BY SATURDAY. THAT WILL BRING THE
WARMER TEMPERATURES TO THE AREA. UNLIKE THIS LAST DEEP UPPER TROUGH
WHEN THE POLAR JET WAS WELL SOUTH OF MICHIGAN FOR SEVERAL DAYS...
THIS TIME IT WILL BE ONLY FOR A DAY. THAT MEANS THERE WILL NOT BE
ENOUGH COLD AIR ALOFT FOR AFTERNOON CONVECTION. HENCE THE DRY
FORECAST FOR WEDNESDAY AFTERNOON THROUGH SATURDAY.
ONE THING TO WATCH FOR... TUESDAY NIGHT WE HAVE THE JET EXIT REGION
OVER SOUTHWEST MICHIGAN. THAT MAY BE ENOUGH TO SUPPORT SOME
THUNDERSTORM ACTIVITY. HOWEVER AT THIS POINT IT LOOKS LIKE TO MUCH
DRY AIR AT MID LEVELS. EVEN SO I HAVE LOW CHANCE POPS FOR THE
SOUTHERN SECTIONS OF THE CWA TUESDAY NIGHT INTO WEDNESDAY MORNING
JUST I CASE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1155 PM EDT SAT AUG 2 2014
MVFR TO LOCALLY IFR CONDITIONS IN FOG DEVELOPING BY 09-10Z.
CONDITIONS IMPROVING TO VFR AFTER 13Z SUNDAY. NO CONVECTION
ANTICIPATED ON SUNDAY AFTERNOON.
&&
.MARINE...
ISSUED AT 330 AM EDT SUN AUG 3 2014
A WEAK PRESSURE GRADIENT WILL CONTINUE TO RESULT IN FAIRLY MINIMAL
WIND AND WAVE ACTION THE NEXT COUPLE OF DAYS WITH WAVE HEIGHTS UNDER
TWO FEET. HOWEVER SOME PATCHY FOG THAT MAY BE DENSE AT TIMES IS
ANTICIPATED THAT WILL CONTINUE TO POSE A HAZARD TO MARINERS DUE TO
RELATIVELY COLD LAKE WATERS AND HIGHER DEW POINT AIR JUST ABOVE
THE LAKE SURFACE.
&&
.HYDROLOGY...
ISSUED AT 306 PM EDT SAT AUG 2 2014
NO HYDRO ISSUES DUE TO A FAIRLY DRY WEATHER PATTERN. BRIEF PERIODS
OF LOCALLY HEAVY RAINFALL ARE POSSIBLE THIS EVENING IN SCATTERED
THUNDERSTORMS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...LAURENS
SHORT TERM...LAURENS
LONG TERM...WDM
AVIATION...MEADE
HYDROLOGY...93
MARINE...LAURENS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1021 AM EDT SUN AUG 3 2014
.SYNOPSIS...A SLOW MOVING UPPER LEVEL TROUGH OVER THE TENNESSEE
VALLEY COUPLED WITH A STATIONARY SURFACE BOUNDARY STRETCHING SOUTH
TO NORTH OVER COASTAL CAROLINAS WILL MAINTAIN A MOIST AND UNSETTLED
WEATHER PATTERN OVER MOST OF CENTRAL NC THROUGH MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 AM SUNDAY...
UPPER LEVEL TROUGH REMAINS WEST OF THE AREA WITH UPPER LEVEL LOW
PRESSURE CENTERED OVER THE OHIO VALLEY. UPPER AIR ANALYSIS FROM 12Z
SHOWS SHEAR AXIS ASSOCIATED WITH SHORTWAVE EXTENDING DOWN THROUGH
TENNESSEE. THIS WAVE WILL MOVE INTO THE NW PIEDMONT LATER TODAY AND
HOPEFULLY WILL ACT AS AN ERODING MECHANISM TO BEGIN BREAKING UP THE
CAD WEDGE...AT LEAST THE TRIAD. TIMING OF THIS FEATURE WILL BE TOUGH
BUT THE RAP HAS IT MAKING HEADWAY INTO THE TRIAD BY EARLY AFTERNOON
WITH A SUBSEQUENT DROP IN DEWPOINTS AND RELATIVE HUMIDITY. THEREFORE
EXPECTING A SIMILAR DEPICTION OF THE PRECIP TO WHAT THE RADAR IS
SHOWING NOW WHICH IS A VERY DEFINITIVE LINE OF PRECIP IN THE COASTAL
PLAIN WITH MUCH DRIER CONDITIONS WEST OF I-95. THAT BEING SAID...THE
TRIANGLE AREA WILL PROBABLY STAY CLOUDY FOR MUCH OF THE DAY WITH
ONLY THE NW PIEDMONT HAVING A REAL CHANCE OF BREAKING OUT THIS
AFTERNOON. THIS WILL MAKE TEMPERATURES TRICKY WITH AN ABNORMAL
DISTRIBUTION OF WARMEST TEMPERATURES IN THE NW AND COOLEST IN THE
SOUTHEAST. IF THE CAD BREAKS DOWN...COULD EASILY SEE LOWER 80S IN
THE TRIAD WITH POSSIBLY ONLY MID 70S IN THE SOUTHEAST. THE GREATEST
THREAT FOR PRECIPITATION WILL BE IN THE EXTREME SOUTHEAST TODAY WITH
SAMPSON COUNTY BEING MONITORED AT THIS TIME FOR POTENTIAL URBAN AND
SMALL STREAM FLOODING. KLTX RADAR INDICATES BETWEEN 2 AND 3 INCHES
OF RAIN FALLEN IN THIS LOCATION ALREADY WITH SOME FURTHER TRAINING
OF MODERATE TO HEAVY RAIN POSSIBLE OVER THE NEXT FEW HOURS. THE
FLOOD WATCH REMAINS IN EFFECT THROUGH 00Z MONDAY FOR THE EASTERN
TIER OF COUNTIES. NOT EXPECTING MUCH IN THE WAY OF SEVERE WEATHER
THIS AFTERNOON ALTHOUGH THERE WILL BE SOME DECENT INSTABILITY IN THE
EAST...SHEAR VALUES HAVE DROPPED OFF SIGNIFICANTLY BUT ARE STILL AT
A MODEST 25 KTS. AS IN PREVIOUS DAYS...THE EXTENSIVE OVERCAST AND
LACK OF INSOLATION SHOULD INHIBIT MOST THUNDERSTORM ACTIVITY THIS
AFTERNOON.
IF SOME CLEARING DOES OCCUR IN THE TRIAD...CAN EXPECT ANOTHER ROUND
OF POTENTIALLY DENSE FOG OVERNIGHT. ELSEWHERE A PERSISTENCE FORECAST
OF LIFR/IFR CEILINGS WILL PROBABLY WORK OUT WELL. THERE SHOULD BE A
LULL IN PRECIPIATION AS PRECIPITATION BEGINS TO PUSH EASTWARD
OFFSHORE. LOW TEMPERATURES TONIGHT MID 60S NW TO NEAR 70 SE.
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
AS OF 420 AM SUNDAY...
STILL A DECENT THREAT FOR ADDITIONAL SHOWERS AND STORMS OVER OUR
EASTERN PERIPHERY AS MID-UPPER LEVEL SHEAR AXIS WITHIN THE MOISTURE
PLUME ONLY DRIFTS SLOWLY EWD. PLAN TO HAVE LIKELY POPS OVER THE
COASTAL PLAIN AND SANDHILLS...TAPERING TO A SMALL CHANCE IN THE
WESTERN PIEDMONT. AFTER MORNING LOW CLOUDS AND FOG BURN-OFF...EXPECT
PARTIAL SUNSHINE ACROSS THE PIEDMONT. THIS SHOULD WARM TEMPS INTO
THE LOW-MID 80S. A SURFACE WAVE LIFTING NEWD JUST OFFSHORE WILL
MAINTAIN A THREAT FOR SHOWERS ACROSS THE COASTAL PLAIN THROUGH THE
OVERNIGHT HOURS. AGAIN...SHOULD SEE AREAS OF LOW CLOUDS AND/OR FOG
DEVELOP. MIN TEMPS MID 60S TO AROUND 70.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 320 AM SUNDAY...
TUESDAY THROUGH WEDNESDAY NIGHT: HIGHER PW`S ARE EXPECTED TO PUSH TO
THE EAST OF THE AREA DURING THE PERIOD AS WE CONTINUE TO TRANSITION
TO MORE OF A TYPICAL SUMMERTIME PATTERN. MID LEVEL TROUGHING ACROSS
THE EASTERN U.S. WILL REMAIN THOUGH... WITH A LEE SIDE TROUGH
DEVELOPING/BECOMES MORE ESTABLISHED OVER THE AREA. THIS WILL LEAD TO
MORE OF A SLIGHT CHANCE/LOW END CHANCE OF SHOWERS AND STORMS FOR
TUESDAY... WITH EVEN A LESSER CHANCE ON WEDNESDAY (BEST CHANCE
ACROSS THE EAST). GIVEN THE DRIER MID LEVEL AIR EXPECTED TO MOVE
INTO THE AREA DURING THIS TIME... EXPECT WE SHOULD SEE MORE INCOMING
SOLAR RADIATION... RESULTING IN WARMING TEMPS BOTH DAYS AS AFTERNOON
LOW LEVEL THICKNESS VALUES AREA EXPECTED TO CLIMB INTO 1415-1430
METER RANGE... HIGHEST WEDNESDAY IN ADVANCE OF ANOTHER FRONT. THIS
WILL YIELD A CONTINUED WARMING TREND... WITH HIGHS AT LEAST IN THE
UPPER 80S TO LOWER 90S ON TUESDAY... WITH HIGHS A FEW DEGREES WARMER
ON WEDNESDAY (WITH POSSIBLY SOME MID 90S SOUTH). LOWS ARE EXPECTED
TO BE IN THE MID TO UPPER 60S... WITH SOME LOWER 70S SOUTH/SOUTHEAST.
THURSDAY THROUGH SATURDAY: A NORTHERN STREAM TROUGH IS EXPECTED TO
AMPLIFY THE MID LEVEL TROUGH ACROSS THE EASTERN U.S. AND SEND
ANOTHER COLD FRONT INTO AND POSSIBLY ACROSS CENTRAL NC ON THURSDAY.
THIS SHOULD LEAD TO A BETTER CHANCE OF SHOWERS AND STORMS ON
THURSDAY. HOWEVER... THIS WILL DEPEND ON THE ACTUAL TIMING OF THE
FRONT. FOR NOW WILL TREND CLOSER TO WPC... WHICH IS SIMILAR TO THE
LATEST ECMWF ALLOWING THE FRONT TO BECOME MORE ACTIVE AS IT MOVES
INTO THE AREA DURING PEAK HEATING ON THURSDAY. THE SURFACE FRONT IS
EXPECTED TO STALL NEAR THE NC/SC BORDER... LEADING TO CONTINUED
CHANCES OF SHOWERS AND STORMS... ESPECIALLY ACROSS THE SOUTHERN HALF
OF THE AREA. EXPECT HIGHS WILL BE COOLER BEHIND THE FRONT. FOR NOW
WILL STICK CLOSE TO WPC... HIGHS IN THE 80S... LOWS IN THE 60S.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 740 AM SUNDAY...
ADVERSE AVIATION WEATHER CONDITIONS WILL PERSIST ACROSS MUCH OF
CENTRAL NC THROUGH MONDAY AS THE LOW LEVEL AIR MASS WILL REMAIN VERY
MOIST AND A SERIES OF UPPER LEVEL DISTURBANCES TRIGGER SCATTERED
SHOWERS AND STORMS. THE GREATEST RISK FOR SHOWERS AND POSSIBLY A
THUNDERSTORM WILL BE IN VICINITY OF KFAY AND KRWI. THE RISK FOR
SHOWERS WILL DIMINISH APPRECIABLY AS YOU GO FARTHER WEST INTO THE
PIEDMONT AND FOOTHILLS. WIDESPREAD IFR/LIFR CEILINGS WILL PERSIST
OVERNIGHT INTO THE FIRST HALF OF THIS MORNING WITH AREAS OF DENSE
FOG...MAINLY ACROSS THE WESTERN AND SOUTHERN PIEDMONT.
A SLOW IMPROVEMENT IN AVIATION CONDITIONS SHOULD OCCUR LATER TODAY
IN THE WESTERN PIEDMONT AS DRIER AIR ALOFT MIXES TOWARD THE
SURFACE...AIDING TO DIMINISH LOW LEVEL CLOUDINESS. THERE IS A GOOD
CHANCE THAT VFR CONDITIONS WILL RETURN TO KINT AND KGSO BY EARLY
AFTERNOON. ELSEWHERE...SUB VFR CONDITIONS WILL PERSIST.
ANOTHER ROUND OF MVFR/IFR CEILINGS AND IFR/LIFR FOG APPEARS LIKELY
TONIGHT INTO EARLY MONDAY. EXPECT TO SEE CONDITIONS IMPROVE TO VFR
AT KRDU...KGSO AND KINT BY LATE MORNING-EARLY AFTERNOON MONDAY WHILE
MOSTLY MVFR CONDITIONS LINGER AT KFAY AND KRWI WHERE A RISK OF
SHOWERS AND POSSIBLY A THUNDERSTORM WILL REMAIN.
A SLOW IMPROVEMENT IN AVIATION CONDITIONS ANTICIPATED TUESDAY
THROUGH THURSDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH THROUGH THIS EVENING FOR NCZ028-043-078-088-089.
&&
$$
SYNOPSIS...WSS
NEAR TERM...ELLIS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1015 AM EDT SUN AUG 3 2014
.SYNOPSIS...
A COASTAL FRONT WILL KEEP THE WEATHER UNSETTLED TODAY. RAIN CHANCES
CONTINUE OR POSSIBLY INCREASE ON MONDAY AS A TROPICAL WAVE MOVES
NORTHWARD BY THE AREA. BERTHA WILL REMAIN MUCH TOO FAR OFFSHORE FOR
ANY DIRECT IMPACTS THROUGH TUESDAY. MORE SEASONABLE WEATHER RETURNS
WEDNESDAY AND THURSDAY. COOLER WEATHER IS THEN SLATED FOR THE LATE
WEEK PERIOD BEHIND A COLD FRONT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 10 AM SUNDAY...A HEAVY BAND OF SHOWERS AND THUNDERSTORMS
HAS DEVELOPED INLAND THIS MORNING. ENHANCED ISENTROPIC LIFT IN AN
AREA OF 850-500MB LAYER RH GREATER THAN 95% IS PARTLY RESPONSIBLE
BUT SO IS AN AREA OF 850 MB FRONTOGENESIS. ALL OF THIS IS BEING
AIDED BY DIVERGENCE ALOFT. SOME OF THESE AREAS HAVE BEEN SHOWING
2 TO 2.5 INCH PER HOUR RAINFALL RATES. GFS HAS THE LOCATION OF
THESE FEATURES FAIRLY CLOSE TO REALITY AND SHOWS THE ISENTROPIC
LIFT AND FRONTOGENESIS SHIFTING OF TO THE NORTH-NORTHEAST AROUND
MIDDAY.
FOR THE REMAINDER OF THE AREA THE SETUP REMAINS RELATIVELY
UNCHANGED. THE TROUGH HAS SHIFTED BACK TO THE COAST...AS IT DID
YESTERDAY MORNING. TROUGH WILL ONCE AGAIN TRY TO MOVE INLAND TODAY
AND THINK IT WILL HAVE A LITTLE MORE SUCCESS THIS AFTERNOON AS THE
HIGH WEDGING DOWN THE COAST IS NOT QUITE AS STRONG AS IT WAS
YESTERDAY. DEEP MOISTURE REMAINS IN PLACE...WITH PRECIPITABLE
WATER VALUES REMAINING ABOVE 2 INCHES...ALONG WITH SOME WEAK
INSTABILITY. STORM MOTION IS SLOWER THAN THE PAST FEW
DAYS...AROUND 7 KT...AND WARM LAYER REMAINS QUITE DEEP AROUND 15K
FT. FLOODING WILL REMAIN A CONCERN WITH ANY STORMS THAT DO
DEVELOP...ESPECIALLY GIVEN THE AMOUNT OF RAINFALL IN MANY AREAS
OVER THE LAST FEW DAYS.
TEMPERATURES THIS AFTERNOON WILL REMAIN WELL BELOW CLIMO WITH
HIGHS RUNNING IN THE UPPER 70S TO LOWER 80S.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...MONDAYS FORECAST WILL NOW HINGE UPON WHAT MAY
END UP BEING A COMPLEX (AND POORLY SAMPLED) INTERACTION BETWEEN TWO
CIRCULATIONS OFF THE EAST COAST...BERTHA AND TROPICAL WAVE NOW IN
THE BAHAMAS. WRF SCORED A BIT OF A COUP WHEN IT STARTED SHOWING THIS
LAST NIGHT. THE QUESTION THAT NOW REMAINS TO BE SEEN...WHICH
CIRCULATION BECOMES THE DOMINANT ONE? WRF MAINTAINS THAT IT WILL BE
THE WESTERN SYSTEM AND THAT THE COAST IS IN FOR QUITE A RAINSTORM
FOLLOWING A WET WEEKEND AND OUR CURRENT FLOOD WATCH WILL LIKELY NEED
TO BE EXTENDED. BERTHA CURRENTLY UNDERGOING LAND INTERACTION WITH
HISPANIOLA...AND SEEMINGLY MAINTAINING A FAIR AMOUNT OF
CONVECTION...AND SO RIGHT NOW IT SEEMS THAT THE WRF IS A BIT
EXTREME. GFS LAST NIGHT PRETTY MUCH IGNORED THE BAHAMA LOW BUT NOW
GIVES IT AN IDENTITY THROUGH THE PERIOD WHILE SEEMINGLY PLAUSIBLY
KEEPING BERTHA AS A SEPARATE ENTITY. THE MAIN PROBLEM WITH THE GFS
IS IT SEEMS ERRONEOUSLY SLOW WITH THE WESTERN LOW AND SHOWS
SURPRISINGLY LITTLE QPF FOR A SYSTEM THAT IS NOT ONLY OF TROPICAL
ORIGIN BUT ALSO POSSIBLY TAPPING SOME MOISTURE FROM A TROPICAL
STORM. THIS SYSTEM WILL LIKELY STILL BE PUSHING MOISTURE TOWARDS THE
COAST MONDAY NIGHT INTO TUESDAY MORNING. TUESDAY AFTERNOON WILL
BRING A DRYING TREND AT LEAST IN THE MID LEVELS. RAIN CHANCES WILL
BE ON THE DECLINE AND THE AREA MAY START TO SEE SOME MORE BREAKS OF
SUN THAN IT HAS RECENTLY.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 3 PM SUNDAY...WEDNESDAY WILL OFFER UP SEASONABLY WARM
WEATHER AND MINIMAL RAIN CHANCES. NEARLY ZONAL/WESTERLY MID LEVEL
FLOW LOCALLY AROUND PERSISTENT TROUGHINESS IN THE NORTHEAST TO KEEP
THINGS FAIRLY DRY. VERY LOW RAIN CHANCES COMING FROM SEA BREEZE AND
PIEDMONT TROUGH WHERE AN ISOLATED SHOWER OR TSTM CANNOT BE RULED
OUT. AFOREMENTIONED UPPER TROUGH SHARPENS ON THURSDAY DRIVING A LATE
DAY COLD FRONT INTO THE REGION. WITH THE LACK OF MID LEVEL MOISTURE
AND EVEN NO APPRECIABLE INFLUX OF GULF OR ATLANTIC LOW LEVEL
MOISTURE AHEAD OF THE BOUNDARY ITS HARD TO IMAGINE HOW IT BRINGS AN
APPRECIABLE INCREASE IN RAIN CHANCES. AS IT STALLS TO OUR SOUTH IT
WILL USHER IN SOME COOLER AIR OVER THE WEEKEND. TOUGH TO SAY HOW
MUCH PENDING HOW CLOUDY IT GETS VS THE ACTUAL AIRMASS CHANGE/COOL
ADVECTION.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
AS OF 12Z...STALLED FRONT/TROUGH WILL CONTINUE OVER THE REGION WITH
CONVECTION FIRING ALONG THE COAST ALL MORNING. INLAND TERMINALS WILL
REMAIN IFR AT LEAST THROUGH 15Z...PERHAPS INTO THE AFTERNOON.
PREDOMINATELY MVFR ALONG THE COAST WITH OCCASIONAL THUNDER POSSIBLE
WITH BRIEF HEAVY RAIN. THE HRRR MODEL INDICATES PRECIP MAY MOVE
INLAND FROM THE COAST BY NOON...BUT CONFIDENCE IS RATHER LOW.
TONIGHT...SHOWERS WILL RETURN DUE TO AN INVERTED TROUGH FROM LOW
PRESSURE MOVING UP FROM THE SOUTH.
EXTENDED OUTLOOK...SHRA/TSRA LIKELY WITH PERIODS OF MVFR CONDITIONS
THROUGH TUESDAY AS A FRONT STALLS AND FINALLY DISSIPATES OVER THE
EASTERN CAROLINAS. A CHANCE OF SHOWERS CONTINUES ON WEDNESDAY LATE
INTO THURSDAY MORNING.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 10 AM SUNDAY...SOUTHEAST FLOW 10 TO 15 KT WILL CONTINUE
THROUGH THE PERIOD. TROUGH STALLED ALONG THE COAST THIS MORNING
WILL SLOWLY PUSH INLAND TODAY. CONVECTION IS LIKELY TO CONTINUE
OVER THE WATERS BUT WITH COVERAGE DECREASING. SEAS WILL RUN 3
FT...MAINLY AS SOUTHEAST WIND WAVE...THOUGH 4 FT IS POSSIBLE IN
AND AROUND CONVECTION.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...PRETTY DIFFICULT FORECAST ON MONDAY. WINDS WILL
BE MAINLY A FUNCTION OF THE INTERACTION BETWEEN BERTHA AND A
TROPICAL WAVE NOW OVER THE BAHAMAS. MODEL SOLUTIONS VARY
CONSIDERABLY AS TO HOW THESE TWO WILL INTERACT AND WHICH ONE WILL
END UP BECOMING A DOMINANT CIRCULATION AS THEY BOTH PASS NORTHWARD
ACROSS OUR LATITUDE ON MONDAY. BERTHA CURRENTLY INTERACTING WITH
HISPANIOLA FURTHER COMPLICATING THE ISSUE. SOUTHEASTERLY WINDS
SHOULD BE PREDOMINANT LOCALLY EITHER WAY...ALTHOUGH THE STRENGTH OF
THESE WINDS AND TO A LESSER EXTENT THE MAGNITUDE OF SEAS REALIZED
WILL BE MODULATED BY WHICH SYSTEM TAKES OVER. SHOULD IT BE BERTHA
THEN THE CURRENT FCST APPLIES. SHOULD THE WESTWARD WAVE TAKE OVER
THEN WINDS MAY BE A BIT HIGHER IN SPEED AND CHANGE MORE THROUGH THE
DAY AS THE FCST ZONES EXPERIENCE MORE CLOSED ISOBARS. A SMALL CRAFT
ADVISORY IS GETTING TOUGH TO RULE OUT ESP FOR NRN ZONES BUT THERE IS
JUST TOO MUCH UNCERTAINTY TO RAISE AT THIS POINT. EITHER WAY WINDS
SHOULD SWING AROUND TO THE NORTH AND THEN WEST ON TUESDAY AS THE
SYSTEMS ACCELERATE OFF TO THE NORTH AND EAST. SUCH A TURN TO
OFFSHORE OFTEN ACTS TO DIMINISH NEARSHORE SEAS AS LANDMASS WAVE
SHADOWING TAKES OVER BUT THERE WILL BE ENOUGH BACKSWELL TO MINIMIZE
THIS FOR MUCH OF TUESDAY. THE EXCEPTION SHOULD BE BRUNSWICK WATERS
WHERE THERE WILL NOT ONLY BE WESTERLY SHADOWING OF WIND WAVES BUT
ALSO A SWELL SHADOWING FROM CAPE FEAR.
LONG TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 3 PM SUNDAY...WEAK PIEDMONT TROUGHINESS TAKES SHAPE ON
WEDNESDAY YIELDING A SOUTHWESTERLY WIND OF FAIRLY `SEASONABLE`
SPEED. SEAS NORMALLY 2 TO 3 FT IN SUCH A SETUP BUT A REMNANT
EASTERLY SWELL MAY STILL BE GIVING RISE TO 4 FT DOMINANT WAVES OVER
NRN ZONES. THE TROUGH MOVES CLOSER TO THE COAST ON THURSDAY WHILE A
COLD FRONT ALSO APPROACHES FROM THE NW. OVERALL THE GRADIENT WILL
EASE AND THE FLOW MAY BACK TO SRLY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR SCZ017-023-024-032-
033-039-053>056.
NC...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR NCZ087-096-099-
105>110.
MARINE...NONE.
&&
$$
SYNOPSIS...MBB
NEAR TERM...III
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...43
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
642 AM EDT SUN AUG 3 2014
.SYNOPSIS...
A COASTAL FRONT WILL KEEP THE WEATHER UNSETTLED TODAY. RAIN CHANCES
CONTINUE OR POSSIBLY INCREASE ON MONDAY AS A TROPICAL WAVE MOVES
NORTHWARD BY THE AREA. BERTHA WILL REMAIN MUCH TOO FAR OFFSHORE FOR
ANY DIRECT IMPACTS THROUGH TUESDAY. MORE SEASONABLE WEATHER RETURNS
WEDNESDAY AND THURSDAY. COOLER WEATHER IS THEN SLATED FOR THE LATE
WEEK PERIOD BEHIND A COLD FRONT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 6:30 AM SUNDAY...NO CHANGES TO THE FORECAST WITH THE LATEST
UPDATE. PREVIOUS DISCUSSION FOLLOWS:
LATEST WRINKLE IN THE NEAR TERM FORECAST CONCERNS FORMATION OF A
TROPICAL DISTURBANCE OVER THE BAHAMAS. SYSTEM IS MOVING NORTH AT
AROUND 10 MPH. ALTHOUGH THE NHC SAYS DISTURBANCE IS SHOWING NO
SIGNS OF ORGANIZATION AND ONLY GIVES IT A 10 PERCENT CHANCE OF
FORMATION OUT THROUGH 5 DAYS...NAM AND TO A LESSER EXTEND THE GFS
HINT AT AN INTERACTION BETWEEN THIS FEATURE AND AN INVERTED
TROUGH/TROPICAL WAVE FEATURE JUST OFFSHORE THAT COULD MARKEDLY
INCREASE PRECIPITATION CHANCES OVERNIGHT. THE ECMWF IS ALSO IN
THIS CAMP WITH THEIR LATEST AVAILABLE GUIDANCE. IF THIS SCENARIO
COME TO PASS...WE WILL HAVE TO CONSIDER EXTENDING THE PRESENT
FLOOD WATCH THROUGH TONIGHT.
IN ANY CASE...CONDITIONS REMAIN FAVORABLE FOR PERIODS OF HEAVY RAIN
AT LEAST THROUGH THE DAYLIGHT HOURS..SO WILL BE KEEPING THE RESENT
FLOOD WATCH UP INTO THE NEAR TERM. A PERSISTENT AND NEARLY
STATIONARY FRONT IS ANALYZED OVER OUR NC AND SC COASTAL PLAIN
COUNTIES THIS MORNING. MODEL CONSENSUS HAS THIS FRONT WAVERING BACK
AND FORTH THROUGH THE PERIOD...ALTHOUGH TIMING OF FRONT PLACEMENT IS
LOW CONFIDENCE DUE TO MODEL SPREAD IN ITS MOTION. AT THE UPPER
LEVELS A LONG-WAVE TROUGH WILL MAINTAIN ITS HOLD OVER EASTERN CONUS
AS A SERIES OF WEAK DISTURBANCES ROUND ITS BASE AND MOVE NE OVER THE
EASTERN CAROLINAS. WATER VAPOR LOOPS CONTINUE TO SHOW A TROPICAL
PLUME OF MOISTURE ADVECTING NE OVER THE FORECAST AREA...ESPECIALLY
OVER THE COASTAL PLAIN. MODEL SOUNDINGS ALSO CONTINUE TO SHOW A
DEEPLY MOIST COLUMN THROUGH THE PERIOD...WITH A MODERATELY UNSTABLE
AIRMASS AND P/W VALUES WELL IN EXCESS OF 2 INCHES. ALL ELEMENTS
REMAIN IN PLACE FOR POTENTIAL WIDESPREAD SHOWER AND THUNDERSTORM
ACTIVITY...WITH THE ATTENDANT HEAVY RAIN THREAT CONTINUING WELL INTO
TODAY.
GUIDANCE HAS BEEN WOEFULLY POOR LATELY IN CAPTURING THE UNUSUALLY
LOW MAXIMUM TEMPERATURES BROUGHT ABOUT BY EXTENSIVE CLOUD COVER AND
PRECIPITATION. SO...WILL GO SIGNIFICANTLY UNDER GUIDANCE BY LIMITING
MAXIMUM TEMPERATURES TO THE LOWER 80S FOR TODAY. OVERNIGHT LOWS WILL
HOVER AROUND 70.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...MONDAYS FORECAST WILL NOW HINGE UPON WHAT MAY
END UP BEING A COMPLEX (AND POORLY SAMPLED) INTERACTION BETWEEN TWO
CIRCULATIONS OFF THE EAST COAST...BERTHA AND TROPICAL WAVE NOW IN
THE BAHAMAS. WRF SCORED A BIT OF A COUP WHEN IT STARTED SHOWING THIS
LAST NIGHT. THE QUESTION THAT NOW REMAINS TO BE SEEN...WHICH
CIRCULATION BECOMES THE DOMINANT ONE? WRF MAINTAINS THAT IT WILL BE
THE WESTERN SYSTEM AND THAT THE COAST IS IN FOR QUITE A RAINSTORM
FOLLOWING A WET WEEKEND AND OUR CURRENT FLOOD WATCH WILL LIKELY NEED
TO BE EXTENDED. BERTHA CURRENTLY UNDERGOING LAND INTERACTION WITH
HISPANIOLA...AND SEEMINGLY MAINTAINING A FAIR AMOUNT OF
CONVECTION...AND SO RIGHT NOW IT SEEMS THAT THE WRF IS A BIT
EXTREME. GFS LAST NIGHT PRETTY MUCH IGNORED THE BAHAMA LOW BUT NOW
GIVES IT AN IDENTITY THROUGH THE PERIOD WHILE SEEMINGLY PLAUSIBLY
KEEPING BERTHA AS A SEPARATE ENTITY. THE MAIN PROBLEM WITH THE GFS
IS IT SEEMS ERRONEOUSLY SLOW WITH THE WESTERN LOW AND SHOWS
SURPRISINGLY LITTLE QPF FOR A SYSTEM THAT IS NOT ONLY OF TROPICAL
ORIGIN BUT ALSO POSSIBLY TAPPING SOME MOISTURE FROM A TROPICAL
STORM. THIS SYSTEM WILL LIKELY STILL BE PUSHING MOISTURE TOWARDS THE
COAST MONDAY NIGHT INTO TUESDAY MORNING. TUESDAY AFTERNOON WILL
BRING A DRYING TREND AT LEAST IN THE MID LEVELS. RAIN CHANCES WILL
BE ON THE DECLINE AND THE AREA MAY START TO SEE SOME MORE BREAKS OF
SUN THAN IT HAS RECENTLY.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 3 PM SUNDAY...WEDNESDAY WILL OFFER UP SEASONABLY WARM
WEATHER AND MINIMAL RAIN CHANCES. NEARLY ZONAL/WESTERLY MID LEVEL
FLOW LOCALLY AROUND PERSISTENT TROUGHINESS IN THE NORTHEAST TO KEEP
THINGS FAIRLY DRY. VERY LOW RAIN CHANCES COMING FROM SEA BREEZE AND
PIEDMONT TROUGH WHERE AN ISOLATED SHOWER OR TSTM CANNOT BE RULED
OUT. AFOREMENTIONED UPPER TROUGH SHARPENS ON THURSDAY DRIVING A LATE
DAY COLD FRONT INTO THE REGION. WITH THE LACK OF MID LEVEL MOISTURE
AND EVEN NO APPRECIABLE INFLUX OF GULF OR ATLANTIC LOW LEVEL
MOISTURE AHEAD OF THE BOUNDARY ITS HARD TO IMAGINE HOW IT BRINGS AN
APPRECIABLE INCREASE IN RAIN CHANCES. AS IT STALLS TO OUR SOUTH IT
WILL USHER IN SOME COOLER AIR OVER THE WEEKEND. TOUGH TO SAY HOW
MUCH PENDING HOW CLOUDY IT GETS VS THE ACTUAL AIRMASS CHANGE/COOL
ADVECTION.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 12Z...STALLED FRONT/TROUGH WILL CONTINUE OVER THE REGION WITH
CONVECTION FIRING ALONG THE COAST ALL MORNING. INLAND TERMINALS WILL
REMAIN IFR AT LEAST THROUGH 15Z...PERHAPS INTO THE AFTERNOON.
PREDOMINATELY MVFR ALONG THE COAST WITH OCCASIONAL THUNDER POSSIBLE
WITH BRIEF HEAVY RAIN. THE HRRR MODEL INDICATES PRECIP MAY MOVE
INLAND FROM THE COAST BY NOON...BUT CONFIDENCE IS RATHER LOW.
TONIGHT...SHOWERS WILL RETURN DUE TO AN INVERTED TROUGH FROM LOW
PRESSURE MOVING UP FROM THE SOUTH.
EXTENDED OUTLOOK...SHRA/TSRA LIKELY WITH PERIODS OF MVFR CONDITIONS
THROUGH TUESDAY AS A FRONT STALLS AND FINALLY DISSIPATES OVER THE
EASTERN CAROLINAS. A CHANCE OF SHOWERS CONTINUES ON WEDNESDAY LATE
INTO THURSDAY MORNING.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 6:30 AM SUNDAY...NO CHANGES TO THE FORECAST WITH THE LATEST
UPDATE. PREVIOUS DISCUSSION FOLLOWS:
AN INVERTED TROUGH/TROPICAL WAVE FEATURE OVER THE WATERS IS
KEEPING WINDS LIGHT AND VARIABLE WITH SEAS IN THE 3 FT RANGE. A
NEARLY STATIONARY FRONT WILL REMAIN INLAND OR JUST NEAR THE COAST
TODAY AND TONIGHT. WINDS WILL BECOME SOUTHEASTERLY LATER THIS
MORNING IN THE 10 TO 15 KT RANGE...WITH SEAS REMAINING AROUND 3
FT. THESE CONDITIONS WILL PERSIST THROUGH THE NEAR TERM. EXPECT
EXTENSIVE SHOWER AND THUNDERSTORM ACTIVITY OVER THE WATERS AS A
TROPICAL PLUME OF MOISTURE MOVES NORTH ACROSS THE WATERS.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...PRETTY DIFFICULT FORECAST ON MONDAY. WINDS WILL
BE MAINLY A FUNCTION OF THE INTERACTION BETWEEN BERTHA AND A
TROPICAL WAVE NOW OVER THE BAHAMAS. MODEL SOLUTIONS VARY
CONSIDERABLY AS TO HOW THESE TWO WILL INTERACT AND WHICH ONE WILL
END UP BECOMING A DOMINANT CIRCULATION AS THEY BOTH PASS NORTHWARD
ACROSS OUR LATITUDE ON MONDAY. BERTHA CURRENTLY INTERACTING WITH
HISPANIOLA FURTHER COMPLICATING THE ISSUE. SOUTHEASTERLY WINDS
SHOULD BE PREDOMINANT LOCALLY EITHER WAY...ALTHOUGH THE STRENGTH OF
THESE WINDS AND TO A LESSER EXTENT THE MAGNITUDE OF SEAS REALIZED
WILL BE MODULATED BY WHICH SYSTEM TAKES OVER. SHOULD IT BE BERTHA
THEN THE CURRENT FCST APPLIES. SHOULD THE WESTWARD WAVE TAKE OVER
THEN WINDS MAY BE A BIT HIGHER IN SPEED AND CHANGE MORE THROUGH THE
DAY AS THE FCST ZONES EXPERIENCE MORE CLOSED ISOBARS. A SMALL CRAFT
ADVISORY IS GETTING TOUGH TO RULE OUT ESP FOR NRN ZONES BUT THERE IS
JUST TOO MUCH UNCERTAINTY TO RAISE AT THIS POINT. EITHER WAY WINDS
SHOULD SWING AROUND TO THE NORTH AND THEN WEST ON TUESDAY AS THE
SYSTEMS ACCELERATE OFF TO THE NORTH AND EAST. SUCH A TURN TO
OFFSHORE OFTEN ACTS TO DIMINISH NEARSHORE SEAS AS LANDMASS WAVE
SHADOWING TAKES OVER BUT THERE WILL BE ENOUGH BACKSWELL TO MINIMIZE
THIS FOR MUCH OF TUESDAY. THE EXCEPTION SHOULD BE BRUNSWICK WATERS
WHERE THERE WILL NOT ONLY BE WESTERLY SHADOWING OF WIND WAVES BUT
ALSO A SWELL SHADOWING FROM CAPE FEAR.
LONG TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 3 PM SUNDAY...WEAK PIEDMONT TROUGHINESS TAKES SHAPE ON
WEDNESDAY YIELDING A SOUTHWESTERLY WIND OF FAIRLY `SEASONABLE`
SPEED. SEAS NORMALLY 2 TO 3 FT IN SUCH A SETUP BUT A REMNANT
EASTERLY SWELL MAY STILL BE GIVING RISE TO 4 FT DOMINANT WAVES OVER
NRN ZONES. THE TROUGH MOVES CLOSER TO THE COAST ON THURSDAY WHILE A
COLD FRONT ALSO APPROACHES FROM THE NW. OVERALL THE GRADIENT WILL
EASE AND THE FLOW MAY BACK TO SRLY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...FLOOD WATCH THROUGH THIS EVENING FOR SCZ017-023-024-032-033-
039-053>056.
NC...FLOOD WATCH THROUGH THIS EVENING FOR NCZ087-096-099-105>110.
MARINE...NONE.
&&
$$
SYNOPSIS...MBB
NEAR TERM...REK
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...43
MARINE...REK/MBB
AREA FORECAST DISCUSSION
NWS BISMARCK ND
941 AM CDT SUN AUG 3 2014
.UPDATE...
ISSUED AT 941 AM CDT SUN AUG 3 2014
SCATTERED TO NUMEROUS SHOWERS WITH EMBEDDED THUNDERSTORMS WILL
CONTINUE TO MOVE EAST ACROSS WESTERN NORTH DAKOTA THIS MORNING.
THIS ACTIVITY IS ASSOCIATED WITH AN UPPER LEVEL SHORTWAVE
OVERTOPPING A RIDGE AXIS OVER EASTERN MONTANA.
THE LATEST HRRR PROGS THIS ACTIVITY TO CONTINUE TO MOVE EAST OVER
CENTRAL NORTH DAKOTA THROUGH THE AFTERNOON. THE INCREASED CLOUD
COVER MAY INHIBIT DIABATIC FORCING FROM AFTERNOON HEATING. THIS
WILL LIKELY KEEP AFTERNOON THUNDERSTORMS ELEVATED FOR THE MOST
PART...KEEPING THE STRONG TO SEVERE POSSIBILITIES LOW. FOR NOW
WILL KEEP THE ONGOING CONVECTIVE FORECAST AS IS...AND WILL
CONTINUE TO MONITOR CONVECTIVE TRENDS THROUGH THE AFTERNOON.
OTHERWISE...ONLY REMOVED MORNING FOG FROM THE ONGOING FORECAST.
THE REMAINING FORECAST ELEMENTS ARE ON TRACK. THE UPDATED PRODUCTS
HAVE BEEN SENT.
UPDATE ISSUED AT 648 AM CDT SUN AUG 3 2014
FOLLOWING THE 08 AND 09 UTC HRRR AND 06 UTC NAM...THE CURRENT
CONVECTION ACROSS NORTHEAST MONTANA IS FORECAST TO PROPAGATE
SOUTHEAST ALONG THE LOW LEVEL INSTABILITY AXIS INTO SOUTH CENTRAL
NORTH DAKOTA BY 19-20 UTC. GIVEN CURRENT CLOUD COVER SPREADING
AHEAD OF THE CONVECTION...SURFACE DESTABILIZATION AND OVERALL
INTENSIFICATION OF THIS CONVECTION INTO THE AFTERNOON WILL BE
LIMITED. THEREAFTER...THE GENERAL CONSENSUS OF 00 UTC HIGH
RESOLUTION AND GLOBAL GUIDANCE IS FOR A SECOND CONVECTIVE COMPLEX
TO INITIATE ACROSS EASTERN MONTANA INTO SOUTHERN SASKATCHEWAN LATE
THIS AFTERNOON/EVENING AND PROPAGATE AGAIN SOUTHEAST ALONG THE
INSTABILITY AXIS INTO WESTERN AND CENTRAL NORTH DAKOTA TONIGHT.
GIVEN A LIKELY ARRIVAL NEARING TO AFTER SUNSET...THE SEVERE THREAT
WILL BE MARGINAL WITH THIS SECOND ROUND.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 341 AM CDT SUN AUG 3 2014
THE MAIN CONCERN IN THE SHORT TERM IS THUNDERSTORM CHANCES...AND THE
POSSIBILITY THAT SEVERE STORMS ARE POSSIBLE TODAY AND TONIGHT.
CURRENTLY...SURFACE HIGH PRESSURE WAS OVER MANITOBA WITH LOW
PRESSURE ALONG THE FRONT RANGE OF THE ROCKIES. THE UPPER LEVEL RIDGE
OVER THE ROCKIES AND THE TROUGH OVER HUDSON BAY WAS KEEPING THE
NORTHWEST FLOW ALOFT OVER NORTH DAKOTA. AN EMBEDDED SHORTWAVE MOVING
ACROSS MONTANA WAS ASSOCIATED WITH A CONVECTIVE LINE OF SHOWERS THAT
WAS APPROACHING THE WESTERN BORDER OF NORTH DAKOTA.
THE AFOREMENTIONED EASTERN MONTANA SHORTWAVE IS PROGGED TO MOVE
EAST/SOUTHEAST ACROSS NORTH DAKOTA TODAY...FOLLOWED BY ANOTHER GROUP
OF SHORTWAVES TONIGHT. THIS SETUP WILL KEEP SCATTERED THUNDERSTORMS
IN THE FORECAST TODAY AND TONIGHT.
CAPE VALUES LATE THIS MORNING AND AFTERNOON APPROACH OR EXCEED 2000
J/KG OVER WESTERN NORTH DAKOTA...WITH 0-6 KM BULK SHEAR VALUES OVER
40 KNOTS IN THE SAME AREA. THE STORM PREDICTION CENTER ASSESSMENT
WAS THAT THE SEVERE THREAT WAS MARGINAL AND FOR ISOLATED COVERAGE.
WILL MENTION THIS THREAT IN THE HAZARDOUS WEATHER OUTLOOK...BUT
CONFIDENCE NOT HIGH ENOUGH TO MENTION IN GRAPHICAL FORECAST.
IN THE EARLY MORNING HOURS TODAY...SURFACE DEWPOINT TEMPERATURES
WERE IN THE UPPER 50S AND LOWER 60S. EARLIER FORECAST PACKAGE
MENTIONED THE POSSIBILITY OF PATCHY/AREAS OF FOG...AND WILL KEEP
THIS MENTIONED IN THIS MORNING`S FORECAST PACKAGE AS WELL.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 341 AM CDT SUN AUG 3 2014
RATHER NORMAL SENSIBLE SUMMER WEATHER HIGHLIGHTS THE EXTENDED FORECAST.
THE 00 UTC GUIDANCE SUITE IS IN AGREEMENT ON THE LARGE SCALE
PATTERN OF A BROAD...LOW AMPLITUDE RIDGE ACROSS THE WESTERN AND
CENTRAL CONUS...CONTAINING WITHIN IT MULTIPLE LOW PREDICTABILITY
IMPULSES THROUGH THE EXTENDED FORECAST. ALL FIELDS ARE WITHIN ONE
AND A HALF STANDARD DEVIATIONS OR LESS OF NORMAL...SUGGESTING RATHER
AVERAGE EARLY AUGUST WEATHER WITH DAILY ISOLATED TO SCATTERED
THUNDERSTORMS...GIVEN THE AFOREMENTIONED IMPULSES...AND HIGHS IN
THE UPPER 70S TO MID 80S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 648 AM CDT SUN AUG 3 2014
HIGH PRESSURE OVER MANITOBA AND LOW PRESSURE OVER THE FRONT RANGE
WILL KEEP AN EASTERLY WIND FLOW ACROSS THE TAF SITES. EARLY THIS
MORNING FOG WITH MVFR AND IFR VSBYS AT KDIK...AND MVFR VSBYS AT
KBIS/KMOT/KJMS. AREA OF SHOWERS AND THUNDERSTORMS IN EASTERN MONTANA
SHOULD MOVE INTO KISN AFT 13Z...WITH CHANCES OF THUNDERSTORMS AFT
16-18Z AT KMOT/KDIK/KBIS...AND NOT UNTIL TONIGHT AT KJMS. VCTS
CONTINUES THROUGH THE TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TM
SHORT TERM...JV
LONG TERM...AYD
AVIATION...JV
AREA FORECAST DISCUSSION
NWS BISMARCK ND
649 AM CDT SUN AUG 3 2014
.UPDATE...
ISSUED AT 648 AM CDT SUN AUG 3 2014
FOLLOWING THE 08 AND 09 UTC HRRR AND 06 UTC NAM...THE CURRENT
CONVECTION ACROSS NORTHEAST MONTANA IS FORECAST TO PROPAGATE
SOUTHEAST ALONG THE LOW LEVEL INSTABILITY AXIS INTO SOUTH CENTRAL
NORTH DAKOTA BY 19-20 UTC. GIVEN CURRENT CLOUD COVER SPREADING
AHEAD OF THE CONVECTION...SURFACE DESTABILIZATION AND OVERALL
INTENSIFICATION OF THIS CONVECTION INTO THE AFTERNOON WILL BE
LIMITED. THEREAFTER...THE GENERAL CONSENSUS OF 00 UTC HIGH
RESOLUTION AND GLOBAL GUIDANCE IS FOR A SECOND CONVECTIVE COMPLEX
TO INITIATE ACROSS EASTERN MONTANA INTO SOUTHERN SASKATCHEWAN LATE
THIS AFTERNOON/EVENING AND PROPAGATE AGAIN SOUTHEAST ALONG THE
INSTABILITY AXIS INTO WESTERN AND CENTRAL NORTH DAKOTA TONIGHT.
GIVEN A LIKELY ARRIVAL NEARING TO AFTER SUNSET...THE SEVERE THREAT
WILL BE MARGINAL WITH THIS SECOND ROUND.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 341 AM CDT SUN AUG 3 2014
THE MAIN CONCERN IN THE SHORT TERM IS THUNDERSTORM CHANCES...AND THE
POSSIBILITY THAT SEVERE STORMS ARE POSSIBLE TODAY AND TONIGHT.
CURRENTLY...SURFACE HIGH PRESSURE WAS OVER MANITOBA WITH LOW
PRESSURE ALONG THE FRONT RANGE OF THE ROCKIES. THE UPPER LEVEL RIDGE
OVER THE ROCKIES AND THE TROUGH OVER HUDSON BAY WAS KEEPING THE
NORTHWEST FLOW ALOFT OVER NORTH DAKOTA. AN EMBEDDED SHORTWAVE MOVING
ACROSS MONTANA WAS ASSOCIATED WITH A CONVECTIVE LINE OF SHOWERS THAT
WAS APPROACHING THE WESTERN BORDER OF NORTH DAKOTA.
THE AFOREMENTIONED EASTERN MONTANA SHORTWAVE IS PROGGED TO MOVE
EAST/SOUTHEAST ACROSS NORTH DAKOTA TODAY...FOLLOWED BY ANOTHER GROUP
OF SHORTWAVES TONIGHT. THIS SETUP WILL KEEP SCATTERED THUNDERSTORMS
IN THE FORECAST TODAY AND TONIGHT.
CAPE VALUES LATE THIS MORNING AND AFTERNOON APPROACH OR EXCEED 2000
J/KG OVER WESTERN NORTH DAKOTA...WITH 0-6 KM BULK SHEAR VALUES OVER
40 KNOTS IN THE SAME AREA. THE STORM PREDICTION CENTER ASSESSMENT
WAS THAT THE SEVERE THREAT WAS MARGINAL AND FOR ISOLATED COVERAGE.
WILL MENTION THIS THREAT IN THE HAZARDOUS WEATHER OUTLOOK...BUT
CONFIDENCE NOT HIGH ENOUGH TO MENTION IN GRAPHICAL FORECAST.
IN THE EARLY MORNING HOURS TODAY...SURFACE DEWPOINT TEMPERATURES
WERE IN THE UPPER 50S AND LOWER 60S. EARLIER FORECAST PACKAGE
MENTIONED THE POSSIBILITY OF PATCHY/AREAS OF FOG...AND WILL KEEP
THIS MENTIONED IN THIS MORNING`S FORECAST PACKAGE AS WELL.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 341 AM CDT SUN AUG 3 2014
RATHER NORMAL SENSIBLE SUMMER WEATHER HIGHLIGHTS THE EXTENDED FORECAST.
THE 00 UTC GUIDANCE SUITE IS IN AGREEMENT ON THE LARGE SCALE
PATTERN OF A BROAD...LOW AMPLITUDE RIDGE ACROSS THE WESTERN AND
CENTRAL CONUS...CONTAINING WITHIN IT MULTIPLE LOW PREDICTABILITY
IMPULSES THROUGH THE EXTENDED FORECAST. ALL FIELDS ARE WITHIN ONE
AND A HALF STANDARD DEVIATIONS OR LESS OF NORMAL...SUGGESTING RATHER
AVERAGE EARLY AUGUST WEATHER WITH DAILY ISOLATED TO SCATTERED
THUNDERSTORMS...GIVEN THE AFOREMENTIONED IMPULSES...AND HIGHS IN
THE UPPER 70S TO MID 80S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 648 AM CDT SUN AUG 3 2014
HIGH PRESSURE OVER MANITOBA AND LOW PRESSURE OVER THE FRONT RANGE
WILL KEEP AN EASTERLY WIND FLOW ACROSS THE TAF SITES. EARLY THIS
MORNING FOG WITH MVFR AND IFR VSBYS AT KDIK...AND MVFR VSBYS AT
KBIS/KMOT/KJMS. AREA OF SHOWERS AND THUNDERSTORMS IN EASTERN MONTANA
SHOULD MOVE INTO KISN AFT 13Z...WITH CHANCES OF THUNDERSTORMS AFT
16-18Z AT KMOT/KDIK/KBIS...AND NOT UNTIL TONIGHT AT KJMS. VCTS
CONTINUES THROUGH THE TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...JV
LONG TERM...AYD
AVIATION...JV
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
722 AM EDT SUN AUG 3 2014
.SYNOPSIS...
AN AREA OF LOW PRESSURE MOVING UP THE EAST COAST WILL SPREAD
MOISTURE WEST INTO THE LOCAL AREA THIS MORNING. HIGH PRESSURE TO
THE WEST WILL BEGIN TO BUILD OVER THE REGION THIS AFTERNOON AND
THEN WILL MOVE ACROSS THE UPPER OHIO VALLEY ON MONDAY. A COLD
FRONT WILL SLIDE SOUTHEAST INTO THE REGION TUESDAY INTO TUESDAY
NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HAVE BACKED OFF ON PRECIP A LITTLE ALONG THE I-71 CORRIDOR. THE
LATEST HRRR STILL SHOWS PRECIP REACHING KCLE IN A COUPLE OF HOURS.
ALSO ADDED A MENTION OF FOG TO THE KMFD AREA.
PREVIOUS...AS EXPECTED SHOWERS HAVE REDEVELOPED OVER THE EASTERN THIRD OF THE
AREA AS A VORT MAX ROTATES ACROSS THE AREA. EXPECT THE COVERAGE TO
CONTINUE TO INCREASE AND SPREAD WEST. HAVE PUSHED PRECIP CHANCES
WESTWARD TO THE I-71 CORRIDOR WITH LIKELY POPS OVER NE OH AND NW
PA. THE CURRENT ROUND OF SHOWERS WILL WORK THE ATMOSPHERE OVER
AND NOT EXPECTING MUCH IF ANY THUNDER GIVEN THE LACK OF CAPE. THE
PRECIP SHOULD START TO DIMINISH AFTER MIDDAY AND EXPECT MAINLY DRY
WEATHER BY 00Z. THE INTENSITY OF THE PRECIP SHOULD BE MUCH LESS
THAN YESTERDAY AND DO NOT EXPECT FLOODING TO BE AN ISSUE TODAY.
WEAK HIGH PRESSURE WILL DOMINATE IN THE FAR WEST TODAY AND A LOT
OF SUNSHINE IS EXPECTED. THAT SHOULD PUSH TEMPS INTO THE LOWER
80S. THE EASTERN END OF THE AREA WILL BE LUCKY TO GET INTO THE
MIDDLE 70S. HAVE USED A BLEND OF GUIDANCE TEMPS AGAIN TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
THE AREA WILL ENJOY A 24 TO 36 HOUR PERIOD OF DRY WEATHER AS HIGH
PRESSURE BUILDS OVER THE REGION. A COLD FRONT IS STILL ON TRACK TO
MOVE ACROSS THE REGION ON TUESDAY. MOISTURE WILL BEGIN TO INCREASE
LATE TOMORROW...ESPECIALLY IN THE NW. THE LATEST GUIDANCE
CONTINUES TO HINT AT PRECIP JUST NORTH OF KTOL TOMORROW EVENING.
WILL PUT A 20 POP IN FOR A FEW HOURS FOR THAT AREA BUT NOT REALLY
EXPECTING MUCH. MONDAY NIGHT SHOULD BE DRY BUT PRECIP CHANCES WILL
RAMP UP ON TUESDAY. WILL GO WITH CHANCE POPS FOR NOW BUT MAY
EVENTUALLY NEED LIKELY WORDING...ESPECIALLY IN THE SOUTH. WILL SEE
SOME LINGERING PRECIP TUESDAY. STILL GETTING MIXED SIGNALS FROM
THE MODELS FOR WEDNESDAY. SOME OF THE GUIDANCE SUGGESTS THE FRONT
STALLING OUT WITH CONTINUING PRECIP CHANCES. THE PREVIOUS FORECAST
HAD MAINLY DRY WEATHER AND WILL BE OPTIMISTIC AND STICK WITH THAT
SCENARIO FOR THE TIME BEING. TEMPERATURES DURING THE PERIOD SHOULD
BE WITHIN A DEGREE OR TWO OF NORMAL.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
UPPER LEVEL TROUGH WILL MOVE EAST OF THE REGION THURSDAY NIGHT WITH
LARGE AREA OF SURFACE HIGH PRESSURE BUILDING BUILDING OVER THE GREAT
LAKES. YDY THE ECMWF MOVED LOW PRESSURE ACROSS FORECAST AREA ON
FRIDAY...NOW KEEPS HIGH PRESSURE IN PLACE FORCING THE LOW SOUTH OF
THE FORECAST AREA. NOW BOTH MODELS SOLUTION SIMILAR...WITH HIGH
PRESSURE BECOMING ANCHORED OVER THE EASTERN LAKES THROUGH THE
EXTENDED PERIOD. THIS WILL CONTINUE TO PROVIDE A DRY FORECAST WITH
BELOW NORMAL TEMPS.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
EASTERN 2/3 FORECAST AREA SHROUDED BY SCATTERED SHRA...BR AND
STRATUS. CONDITIONS WILL SLOWLY IMPROVE FROM THE WEST DURING THE
DAY AS THE UPPER LEVEL SHORT WAVE OVER OHIO DRIFTS EAST OF THE
AREA THIS AFTERNOON.
OUTLOOK...NON VFR POSSIBLE TONIGHT IN BR AND STRATUS...AGAIN TUESDAY
IN SHOWERS/THUNDERSTORMS.
&&
.MARINE...
WEAK HIGH PRESSURE WILL REMAIN OVER THE LAKE THROUGH MONDAY
PROVIDING LIGHT WINDS ACROSS THE LAKE. MODELS CONTINUE TO PUSH WEAK
COLD FRONT ACROSS THE LAKE LATE TUESDAY. THIS MAY PRODUCE SOME
ISOLATED TO SCATTERED THUNDERSTORMS. AFTER THIS HIGH PRESSURE WILL
THEN REESTABLISH ITSELF OVER THE LAKE INTO NEXT WEEKEND.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KUBINA
NEAR TERM...KUBINA
SHORT TERM...KUBINA
LONG TERM...DJB
AVIATION...DJB
MARINE...DJB
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
625 AM EDT SUN AUG 3 2014
.SYNOPSIS...
AN AREA OF LOW PRESSURE MOVING UP THE EAST COAST WILL SPREAD
MOISTURE WEST INTO THE LOCAL AREA THIS MORNING. HIGH PRESSURE TO
THE WEST WILL BEGIN TO BUILD OVER THE REGION THIS AFTERNOON AND
THEN WILL MOVE ACROSS THE UPPER OHIO VALLEY ON MONDAY. A COLD
FRONT WILL SLIDE SOUTHEAST INTO THE REGION TUESDAY INTO TUESDAY
NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HAVE BACKED OFF ON PRECIP A LITTLE ALONG THE I-71 CORRIDOR. THE
LATEST HRRR STILL SHOWS PRECIP REACHING KCLE IN A COUPLE OF HOURS.
ALSO ADDED A MENTION OF FOG TO THE KMFD AREA.
PREVIOUS...AS EXPECTED SHOWERS HAVE REDEVELOPED OVER THE EASTERN THIRD OF THE
AREA AS A VORT MAX ROTATES ACROSS THE AREA. EXPECT THE COVERAGE TO
CONTINUE TO INCREASE AND SPREAD WEST. HAVE PUSHED PRECIP CHANCES
WESTWARD TO THE I-71 CORRIDOR WITH LIKELY POPS OVER NE OH AND NW
PA. THE CURRENT ROUND OF SHOWERS WILL WORK THE ATMOSPHERE OVER
AND NOT EXPECTING MUCH IF ANY THUNDER GIVEN THE LACK OF CAPE. THE
PRECIP SHOULD START TO DIMINISH AFTER MIDDAY AND EXPECT MAINLY DRY
WEATHER BY 00Z. THE INTENSITY OF THE PRECIP SHOULD BE MUCH LESS
THAN YESTERDAY AND DO NOT EXPECT FLOODING TO BE AN ISSUE TODAY.
WEAK HIGH PRESSURE WILL DOMINATE IN THE FAR WEST TODAY AND A LOT
OF SUNSHINE IS EXPECTED. THAT SHOULD PUSH TEMPS INTO THE LOWER
80S. THE EASTERN END OF THE AREA WILL BE LUCKY TO GET INTO THE
MIDDLE 70S. HAVE USED A BLEND OF GUIDANCE TEMPS AGAIN TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
THE AREA WILL ENJOY A 24 TO 36 HOUR PERIOD OF DRY WEATHER AS HIGH
PRESSURE BUILDS OVER THE REGION. A COLD FRONT IS STILL ON TRACK TO
MOVE ACROSS THE REGION ON TUESDAY. MOISTURE WILL BEGIN TO INCREASE
LATE TOMORROW...ESPECIALLY IN THE NW. THE LATEST GUIDANCE
CONTINUES TO HINT AT PRECIP JUST NORTH OF KTOL TOMORROW EVENING.
WILL PUT A 20 POP IN FOR A FEW HOURS FOR THAT AREA BUT NOT REALLY
EXPECTING MUCH. MONDAY NIGHT SHOULD BE DRY BUT PRECIP CHANCES WILL
RAMP UP ON TUESDAY. WILL GO WITH CHANCE POPS FOR NOW BUT MAY
EVENTUALLY NEED LIKELY WORDING...ESPECIALLY IN THE SOUTH. WILL SEE
SOME LINGERING PRECIP TUESDAY. STILL GETTING MIXED SIGNALS FROM
THE MODELS FOR WEDNESDAY. SOME OF THE GUIDANCE SUGGESTS THE FRONT
STALLING OUT WITH CONTINUING PRECIP CHANCES. THE PREVIOUS FORECAST
HAD MAINLY DRY WEATHER AND WILL BE OPTIMISTIC AND STICK WITH THAT
SCENARIO FOR THE TIME BEING. TEMPERATURES DURING THE PERIOD SHOULD
BE WITHIN A DEGREE OR TWO OF NORMAL.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
UPPER LEVEL TROUGH WILL MOVE EAST OF THE REGION THURSDAY NIGHT WITH
LARGE AREA OF SURFACE HIGH PRESSURE BUILDING BUILDING OVER THE GREAT
LAKES. YDY THE ECMWF MOVED LOW PRESSURE ACROSS FORECAST AREA ON
FRIDAY...NOW KEEPS HIGH PRESSURE IN PLACE FORCING THE LOW SOUTH OF
THE FORECAST AREA. NOW BOTH MODELS SOLUTION SIMILAR...WITH HIGH
PRESSURE BECOMING ANCHORED OVER THE EASTERN LAKES THROUGH THE
EXTENDED PERIOD. THIS WILL CONTINUE TO PROVIDE A DRY FORECAST WITH
BELOW NORMAL TEMPS.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
THE UPPER LEVEL SHORT WAVE OVER CENTRAL OHIO WILL DRIFT EAST OF
THE AREA THIS AFTERNOON...BUT WILL BE ENOUGH TO PRODUCE SHOWERS
OVER THE EASTERN HALF OF THE FORECAST AREA THIS MORNING. CLOUDS
WILL SLOWLY ERODE FROM THE WEST AS SHORT WAVE DRIFTS EAST. IN
AREAS WHERE CLOUDS SCATTER LIKELY SEE MVFR BR WITH AREAS OF IFR
FOG...POTENTIALLY LI FR. THE FOG WILL BURN OFF MID MORNING AND
CUMULUS WILL DEVELOP WITH THE DAYTIME HEATING.
OUTLOOK...NON VFR POSSIBLE TUESDAY IN SHOWERS/THUNDERSTORMS.
&&
.MARINE...
WEAK HIGH PRESSURE WILL REMAIN OVER THE LAKE THROUGH MONDAY
PROVIDING LIGHT WINDS ACROSS THE LAKE. MODELS CONTINUE TO PUSH WEAK
COLD FRONT ACROSS THE LAKE LATE TUESDAY. THIS MAY PRODUCE SOME
ISOLATED TO SCATTERED THUNDERSTORMS. AFTER THIS HIGH PRESSURE WILL
THEN REESTABLISH ITSELF OVER THE LAKE INTO NEXT WEEKEND.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KUBINA
NEAR TERM...KUBINA
SHORT TERM...KUBINA
LONG TERM...DJB
AVIATION...DJB
MARINE...DJB
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
900 AM MDT SUN AUG 3 2014
.UPDATE...
ISSUED AT 856 AM MDT SUN AUG 3 2014
A WEAK WAVE CONTINUES TO MOVE THROUGH THE WESTERN DAKOTAS...PRODUCING
SOME LIGHT SHOWERS ACROSS NORTHEASTERN WYOMING AND FAR WESTERN
SOUTH DAKOTA. WINDS ACROSS THE AREA ARE LIGHT AND VARIABLE...AND
TEMPS ARE IN THE UPPER 60S AND LOWER 70S. UPDATED GRIDS TO
INCREASE POPS SLIGHTLY AND TWEAK SKY GRIDS. REST OF FORECAST LOOKS
FINE AT THIS TIME.
&&
.SHORT TERM...TODAY THROUGH MONDAY NIGHT
ISSUED AT 259 AM MDT SUN AUG 3 2014
UPPER RIDGING CONTINUES ACROSS THE WESTERN CONUS WITH NW FLOW
CROSSING THE NRN PLAINS. WEAK UPPER WAVES CONTINUE TO ROUND THE TOP
OF THE RIDGE OVER THE NRN ROCKIES INTO THE NRN HIGH PLAINS. WV
IMAGERY SHOWS AN UPPER WAVE NOW CROSSING ERN MT BRINGING SHOWERS TO
SE MT. HRRR SHOWS THESE SHOWERS MAKING INTO FAR NE WY THRU NW SD
BEFORE 18Z SO HAVE ADDED SL CHC POPS THERE. MLCAPE FORECAST TO BE
500-1000 J/KG AGAIN TODAY...BUT BETTER LL SHEAR DEVELOPS LATE
AFTN/EVNG AS SFC LOW DEVELOPS JUST NW OF THE CWA. COULD SEE ISOLATED
STRONG STORMS OR PERHAPS A SVR STORM OR TWO.
WRN CONUS RIDGE BREAKS DOWN MONDAY AS UPPER LOW SLIDES INTO GREAT
BASIN. MONSOONAL STORMS WILL DEVELOP ACROSS WY AND BLKHLS...THEN
CROSS INTO THE CWA PLAINS THROUGH THE EVNG. MLCAPE OF 500-1000 AGAIN
EXPECTED...BUT THIS TIME WITH WEAKER AVAILABLE SHEAR. SEVERE STORMS
ARE NOT EXPECTED MON/MON NIGHT.
&&
.LONG TERM...TUESDAY THROUGH SATURDAY
ISSUED AT 259 AM MDT SUN AUG 3 2014
ACTIVE SW FLOW WILL DEVELOP BY TUESDAY...WITH DAILY CHANCE FOR
SHRA/TS THROUGH MOST OF THE WEEK...AS THE NE PAC NEGATIVE HEIGHT
ANOMALY SUPPORTS NUMEROUS LOW AMPLITUDE IMPULSES INTO THE FLOW AND
THE WESTERN RIDGE BREAKS DOWN. MOST ACTIVITY IS EXPECTED TO A HAVE
A STRONG DIURNAL COMPONENT...SUPPORTING THE HIGHEST CHANCES FOR
PRECIP IN THE AFTERNOON PERIODS...AND ESP OVER THE BLACK HILLS
GIVEN OROGRAPHIC INFLUENCES. GENERAL WSW FLOW WILL PERSIST INTO
THE WEEKEND WITH NO NOTED HIGH LATITUDE BLOCKING FAVORED IN MEAN
MODEL AND ENSEMBLE SOLUTIONS UNTIL EARLY NEXT WEEK WHEN THE
EASTERN NOAM UPPER TROUGH MAY MAKE A RETURN.
CARRIED AT LEAST A SLIGHT CHANCE POP MENTION THROUGH THE
PERIOD...RETAINING HIGHER NUMBERS TUESDAY THROUGH WED GIVEN
CONSISTENT SIGNALS FOR ADVECTING IMPULSES WITH APPRECIABLE LL
MOISTURE/WEAK CAPPING/AND A STALLED FRONTAL BOUNDARY OVER THE
REGION. RETAINED HIGHEST NUMBERS OVER THE BLACK HILLS...ESP TUE AND
WED. GENERAL WEAK 0-8 KM FLOW WITH PW VALUES IN EXCESS OF 1 INCH
MOST PLACES WILL SUPPORT AN INCREASED CHANCE FOR HEAVY
RAINFALL...ESP IN THE NORTHERN BLACK HILLS. SOME STRONG TO SEVERE
STORMS CANNOT BE RULED OUT IN THE PERIOD GIVEN POTENTIAL INCREASE IN
MID LEVEL FLOW AND POTENTIAL LL MOISTURE...ESP EARLY IN THE PERIOD.
TEMPERATURES ARE EXPECTED TO BE ON THE COOL SIDE OF SEASONAL NORMS
THROUGH MOST OF THE WEEK. LL EASTERLY FLOW/INCREASED CHANCES FOR
RAIN/AND INCREASED CLOUD COVER ARE ALL EXPECTED TO SUPPORT COOLER
TEMPS. HAVE CONTINUED TO NUDGE TEMPS DOWN TUES GIVEN MODEL/MOS
TRENDS. WARMER WEATHER LOOKS TO RETURN BY THE END OF THE WEEK AS BL
DRYING OCCURS UNDER HEIGHT RISES AND THERMAL RIDGING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 517 AM MDT SUN AUG 3 2014
VFR CONDITIONS EXPECTED THROUGH THE PERIOD MOST PLACES. ISOLD SHRA
WILL BE POSSIBLE ACROSS THE WESTERN HALF THIS MORNING...WITH SCT-
ISOLATED SHRA/TSTMS EXPECTED TO DEVELOP THIS AFTN...ESPECIALLY
OVER THE BLKHLS. LCL MVFR VSBY AND GUSTY WINDS ARE POSSIBLE IN
HEAVIER CELLS THIS AFTERNOON. ISOLD SHRA/TS WILL LINGER THROUGH
TONIGHT...ESP ACROSS NW SD.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
UPDATE...POJORLIE
SHORT TERM...13
LONG TERM...JC
AVIATION...JC
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
956 AM CDT SUN AUG 3 2014
.UPDATE...
ISSUED AT 956 AM CDT SUN AUG 3 2014
HAVE MADE MINOR ADJUSTMENTS TO THE FORECAST. VIS AND WATER VAPOR
IMAGERY SHOWS TWO WAVE MOVES IN THE NORTHERN PLAINS. THE FIRST IS
IN THE RED RIVER VALLEY WITH SOME CONVECTION ASSOCIATED WITH IT. A
STRONGER WAVE WAS JUST MOVING INTO THE WESTERN DAKOTAS. SKIES ARE
CURRENTLY CLEAR ACROSS MOST OF THE AREA...BUT WITH HEATING LATE
THIS MORNING...EXPECT CU TO BEGIN TO DEVELOP FAIRLY
RAPIDLY...FIRST ALONG THE BUFFALO RIDGE AND THEN SPREADING TO MOST
AREAS ALONG AND EAST OF I29. BASED UPON NAM SOUNDINGS...VIRTUALLY
NO CAP WILL EXIST OVER PORTIONS OF SW MN AND NW IA WITH ONLY A
WEAK CAPPING INVERSION AROUND KFSD. THE HRRR DOES SHOW SCATTERED
CONVECTION FORMING DURING THE AFTERNOON IN SW MN AND NW IA. A
STRONGER CAP...AROUND 50 J/KG...EXISTS FARTHER WEST IN THE JAMES
AND MISSOURI VALLEYS AND SHOULD PREVENT ANY CONVECTION TODAY.
THEREFORE EXPECT A FEW THUNDERSTORMS TO DEVELOP DURING THE
AFTERNOON AND PERSIST INTO THE EVENING. BELIEVE CONVECTION WILL
FAVOR THE BUFFALO RIDGE AREA BUT ISOLATED STORMS ARE POSSIBLE
ALMOST ANYWHERE ALONG AND EAST OF 29 AND HAVE INCLUDED SIOUX FALLS
AND MOST OF NW IA IN AREA FOR ISOLATED CONVECTION.
THERE IS ENOUGH INSTABILITY...CAPES BETWEEN 1000 AND 1500 J/KG TO
SUPPORT AT LEAST SMALL HAIL ALTHOUGH...AS MENTIONED IN THE
PREVIOUS DISCUSSION...WITH EFFECTIVE SHEAR AROUND 20 KTS...STORMS
WILL NOT BE ORGANIZED. IN ADDITION...SFC TO 3 KM THETA-E
DIFFERENCE WILL EXCEED 20 K. THE FLOW AROUND 3 KM IS ONLY 10 TO 15
KTS SO NOT A LOT OF MOMENTUM TO BRING DOWN BUT WITH THE POSSIBLE
ACCELERATION OF AIR PARCELS IN THE DOWNDRAFT...A FEW GUSTS TO 30
OR 40 MPH ARE POSSIBLE AS STORMS COLLAPSE. IN ADDITION...WITH
LIGHT SYNOPTIC SCALE WINDS...OUTFLOW BOUNDARIES ARE LIKELY TO
SPREAD OUT FROM CONVECTION AND MAY INCREASE WIND SPEEDS
TEMPORARILY MILES FROM ANY ACTUAL RAIN.
UPDATED GRIDS SENT. WILL BE UPDATING HWO TO ADD THREAT OF SMALL
HAIL AND STRONGER WIND GUSTS TO TODAY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT SUN AUG 3 2014
LAST OF THE OVERNIGHT CONVECTION IS PULLING OUT OF OUR CWA VERY
EARLY THIS MORNING AS THE ASSOCIATED SHORTWAVE DROPS INTO SOUTHERN
IOWA. WITH THE DEPARTURE OF THIS CONVECTION THINK THAT MUCH OF THE
REMAINDER OF THE MORNING AND AFTERNOON WILL BE DRY IN THE ABSENCE OF
ANY SIGNIFICANT FORCING...UNTIL LATER AFTERNOON WHEN A WEAK BOUNDARY
BEGINS TO DROP OUT OF NORTHERN SOUTH DAKOTA. AS ANOTHER SHORTWAVE
FALLS SOUTHWARD THROUGH WESTERN MINNESOTA ON A NORTHWESTERLY UPPER
LEVEL FLOW...MAY GET ENOUGH INTERACTION WITH THE FRONT TO AGAIN KICK
OFF ISOLATED CONVECTION IN OUR EAST IN THE LATE AFTERNOON AND
EVENING...THOUGH MODELS WOULD SUGGEST THAT THE BETTER ACTIVITY WILL
REMAIN TO THE EAST OF OUR CWA. WHILE MODERATE INSTABILITY WILL EXIST
IN THE VICINITY OF THE BOUNDARY...EFFECTIVE SHEAR REMAINS WEAK...SO
WOULD NOT EXPECT ANY REAL ORGANIZATION TO ANY STORMS THAT DEVELOP
AND THINKING THAT ANY SEVERE THREAT IS MINIMAL. AS FOR TEMPERATURES
TODAY...850 MB THERMAL PROFILES ARE SIMILAR TO YESTERDAY AND LOOKING
AT HIGHS ONCE AGAIN IN THE 80S...CLOSING IN ON 90 THROUGH SOUTH
CENTRAL SOUTH DAKOTA.
BY TONIGHT ANY ISOLATED CONVECTION THAT DEVELOPS IN OUR EAST WILL
TREND DOWNWARD THROUGH THE LATER EVENING/EARLY NIGHT TIME HOURS AS
THE ASSOCIATED SHORTWAVE PULLS AWAY FROM THE AREA. IT WILL BE
ANOTHER MILD NIGHT WITH LOWS IN THE LOWER 60S.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 345 AM CDT SUN AUG 3 2014
SUBTLE UPPER WAVE SLIDES SOUTHEAST ACROSS NORTHEAST PORTIONS OF THE
AREA MONDAY. WITH THIS REGION NEAR AXIS OF LOW LEVEL RIDGE...WILL
LIKELY SEE FAIRLY HIGH CLOUD BASES. HOWEVER THESE WEAK WAVES HAVE
BEEN ABLE TO TRIGGER SPOTTY ACTIVITY RECENTLY AND SEE NO REASON WHY
MONDAY SHOULD BE ANY DIFFERENT. MID LEVEL INSTABILITY IS NOT OVERLY
IMPRESSIVE...SO WOULD NOT EXPECT ANY SEVERE STORMS TO DEVELOP.
ATTENTION THEN TURNS TO MORE SIGNIFICANT SYSTEM SET TO AFFECT THE
REGION. FIRST EXPECT ISOLATED TO SCATTERED ELEVATED ACTIVITY MONDAY
NIGHT/TUESDAY WITH THE INITIAL SURGE OF WARM ADVECTION. THIS WILL BE
FOLLOWED TUESDAY NIGHT/WEDNESDAY BY FIRST REAL POTENTIAL FOR MORE
WIDESPREAD...POSSIBLY HEAVY...PRECIPITATION THAT THE REGION HAS SEEN
IN QUITE A WHILE. SEEING SOME DISAGREEMENT IN THE MODELS REGARDING
NORTH-SOUTH PLACEMENT OF THEIR RESPECTIVE PRECIPITATION OUTPUT...BUT
LARGE SCALE FORCING FROM DEEP WARM ADVECTION/ISENTROPIC LIFT/THETA-E
ADVECTION SEEM TO SHOW BETTER CONSENSUS...WHICH CURRENTLY POINTS TO
BETTER CHANCES BETWEEN MISSOURI VALLEY AND I-90 CORRIDOR. THIS LENDS
SOME CONFIDENCE IN BUMPING POPS IN THESE AREAS UP INTO CATEGORICAL
RANGE FOR TUESDAY NIGHT...THOUGH AT THIS TIME LOOKS LIKE FAIRLY GOOD
POTENTIAL FOR AT LEAST MEASURABLE PRECIP OVER MOST OF THE FORECAST
AREA.
SYSTEM WILL GRADUALLY PULL AWAY FROM THE REGION ON WEDNESDAY...AFTER
WHICH TIME MODEL CONSENSUS DIMINISHES AS WELL. MODELS DO GENERALLY
AGREE THAT LONGER RANGE...WEDNESDAY THROUGH SATURDAY...WILL START
OFF ON THE COOL SIDE WITH HIGHS LARGELY BACK IN THE 70S WEDNESDAY
AND THURSDAY. MORE PROGRESSIVE GFS THEN A LITTLE FASTER IN EXPANDING
WARMER AIR BACK INTO THE REGION...ACCOMPANIED BY FAIRLY WET PATTERN
FOR FRIDAY/SATURDAY. MEANWHILE ECMWF/GEM HOLD ONTO COOLER LOW LEVEL
FLOW...WHILE KEEPING THINGS DRY WITH RIDGING ALOFT. GIVEN THESE
DISCREPANCIES...HAVE NOT STRAYED FAR FROM BROAD CONSENSUS GRIDS FOR
THE LATTER PART OF THE FORECAST PERIOD...SHOWING A SLOW WARMING
TREND WITH LOW PRECIP CHANCES EACH DAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 604 AM CDT SUN AUG 3 2014
PATCHY MVFR VISIBILITIES EARLY THIS MORNING...OTHERWISE EXPECTING
VFR CONDITIONS THROUGH THE TAF PERIOD. MAY SEE ISOLATED
THUNDERSTORMS DEVELOP GENERALLY EAST OF INTERSTATE 29 THIS
AFTERNOON AND EVENING...THOUGH NOT EXPECTED TO AFFECT TAF SITES.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...SCHUMACHER
SHORT TERM...JM
LONG TERM...JH
AVIATION...JM
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
520 AM MDT SUN AUG 3 2014
.SHORT TERM...TODAY THROUGH MONDAY NIGHT
ISSUED AT 259 AM MDT SUN AUG 3 2014
UPPER RIDGING CONTINUES ACROSS THE WESTERN CONUS WITH NW FLOW
CROSSING THE NRN PLAINS. WEAK UPPER WAVES CONTINUE TO ROUND THE TOP
OF THE RIDGE OVER THE NRN ROCKIES INTO THE NRN HIGH PLAINS. WV
IMAGERY SHOWS AN UPPER WAVE NOW CROSSING ERN MT BRINGING SHOWERS TO
SE MT. HRRR SHOWS THESE SHOWERS MAKING INTO FAR NE WY THRU NW SD
BEFORE 18Z SO HAVE ADDED SL CHC POPS THERE. MLCAPE FORECAST TO BE
500-1000 J/KG AGAIN TODAY...BUT BETTER LL SHEAR DEVELOPS LATE
AFTN/EVNG AS SFC LOW DEVELOPS JUST NW OF THE CWA. COULD SEE ISOLATED
STRONG STORMS OR PERHAPS A SVR STORM OR TWO.
WRN CONUS RIDGE BREAKS DOWN MONDAY AS UPPER LOW SLIDES INTO GREAT
BASIN. MONSOONAL STORMS WILL DEVELOP ACROSS WY AND BLKHLS...THEN
CROSS INTO THE CWA PLAINS THROUGH THE EVNG. MLCAPE OF 500-1000 AGAIN
EXPECTED...BUT THIS TIME WITH WEAKER AVAILABLE SHEAR. SEVERE STORMS
ARE NOT EXPECTED MON/MON NIGHT.
&&
.LONG TERM...TUESDAY THROUGH SATURDAY
ISSUED AT 259 AM MDT SUN AUG 3 2014
ACTIVE SW FLOW WILL DEVELOP BY TUESDAY...WITH DAILY CHANCE FOR
SHRA/TS THROUGH MOST OF THE WEEK...AS THE NE PAC NEGATIVE HEIGHT
ANOMALY SUPPORTS NUMEROUS LOW AMPLITUDE IMPULSES INTO THE FLOW AND
THE WESTERN RIDGE BREAKS DOWN. MOST ACTIVITY IS EXPECTED TO A HAVE
A STRONG DIURNAL COMPONENT...SUPPORTING THE HIGHEST CHANCES FOR
PRECIP IN THE AFTERNOON PERIODS...AND ESP OVER THE BLACK HILLS
GIVEN OROGRAPHIC INFLUENCES. GENERAL WSW FLOW WILL PERSIST INTO
THE WEEKEND WITH NO NOTED HIGH LATITUDE BLOCKING FAVORED IN MEAN
MODEL AND ENSEMBLE SOLUTIONS UNTIL EARLY NEXT WEEK WHEN THE
EASTERN NOAM UPPER TROUGH MAY MAKE A RETURN.
CARRIED AT LEAST A SLIGHT CHANCE POP MENTION THROUGH THE
PERIOD...RETAINING HIGHER NUMBERS TUESDAY THROUGH WED GIVEN
CONSISTENT SIGNALS FOR ADVECTING IMPULSES WITH APPRECIABLE LL
MOISTURE/WEAK CAPPING/AND A STALLED FRONTAL BOUNDARY OVER THE
REGION. RETAINED HIGHEST NUMBERS OVER THE BLACK HILLS...ESP TUE AND
WED. GENERAL WEAK 0-8 KM FLOW WITH PW VALUES IN EXCESS OF 1 INCH
MOST PLACES WILL SUPPORT AN INCREASED CHANCE FOR HEAVY
RAINFALL...ESP IN THE NORTHERN BLACK HILLS. SOME STRONG TO SEVERE
STORMS CANNOT BE RULED OUT IN THE PERIOD GIVEN POTENTIAL INCREASE IN
MID LEVEL FLOW AND POTENTIAL LL MOISTURE...ESP EARLY IN THE PERIOD.
TEMPERATURES ARE EXPECTED TO BE ON THE COOL SIDE OF SEASONAL NORMS
THROUGH MOST OF THE WEEK. LL EASTERLY FLOW/INCREASED CHANCES FOR
RAIN/AND INCREASED CLOUD COVER ARE ALL EXPECTED TO SUPPORT COOLER
TEMPS. HAVE CONTINUED TO NUDGE TEMPS DOWN TUES GIVEN MODEL/MOS
TRENDS. WARMER WEATHER LOOKS TO RETURN BY THE END OF THE WEEK AS BL
DRYING OCCURS UNDER HEIGHT RISES AND THERMAL RIDGING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 517 AM MDT SUN AUG 3 2014
VFR CONDITIONS EXPECTED THROUGH THE PERIOD MOST PLACES. ISOLD SHRA
WILL BE POSSIBLE ACROSS THE WESTERN HALF THIS MORNING...WITH SCT-
ISOLATED SHRA/TSTMS EXPECTED TO DEVELOP THIS AFTN...ESPECIALLY
OVER THE BLKHLS. LCL MVFR VSBY AND GUSTY WINDS ARE POSSIBLE IN
HEAVIER CELLS THIS AFTERNOON. ISOLD SHRA/TS WILL LINGER THROUGH
TONIGHT...ESP ACROSS NW SD.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
SHORT TERM...13
LONG TERM...JC
AVIATION...JC
AREA FORECAST DISCUSSION...UPDATED
NWS PHOENIX AZ
1215 PM MST SUN AUG 3 2014.
&&
.SYNOPSIS...
AFTER ONE MORE DAY OF WIDESPREAD THUNDERSTORM ACTIVITY TODAY...AS A
UPPER LEVEL LOW CENTER MOVING INLAND INTO SOUTHERN CA AFFECTS OUR
REGION...A SIGNIFICANT DRYING TREND IS THEN EXPECTED TO BEGIN ON
MONDAY...UNDER SOUTHWESTERLY FLOW ALOFT...LIMITING STORM CHANCES TO
EASTERN ARIZONA THROUGH MIDWEEK. A GRADUAL RETURN OF STORM CHANCES
FROM EAST TO WEST IS THEN EXPECTED TO BEGIN BY THE END OF THE
WEEK...PERHAPS CONTINUING INTO THE UPCOMING WEEKEND.
&&
.DISCUSSION...
TODAY AND TONIGHT...
AFTER A QUIET START THIS MORNING...AS DRIER AIR ALOFT SPREAD IN FROM
THE SOUTH ACROSS THE REGION...ONE MORE BUSY AFTERNOON OF TS ACTIVITY
IS EXPECTED TO OCCUR TODAY BEFORE A SIGNIFICANT DRYING TREND TAKES
HOLD FROM MONDAY ONWARD INTO THE MIDDLE OF THIS WEEK. THE PARENT
UPPER LOW THAT BROUGHT THE MOISTURE SURGE INTO THE REGION THE LAST
FEW DAYS IS NOW MAKING ITS CLOSEST APPROACH AS IT MOVES SLOWLY
NORTHWARD INTO SOUTHERN CA. A WEAK VORT LOBE CAN BE SEEN ON WATER
VAPOR IMAGERY SLOWLY ROTATING NORTHWARD AROUND THE UPPER LOW CENTER
INTO SOUTHWEST AZ. LATEST NAM AND GFS FCST SOUNDINGS ARE SHOWING A
30KT SOUTHERLY JET MAX AT 500MB MOVING INTO SOUTHERN AZ THIS
AFTERNOON. THIS MODEST VERTICAL SHEAR...COMBINED WITH AMPLE
LOW-LEVEL MOISTURE...AND MODEST MUCAPES...IN THE 500-750 J/KG
RANGE...WILL LIKELY BE ENOUGH TO TRIGGER SCATTERED-NUMEROUS
THUNDERSTORMS THIS AFTERNOON ACROSS YUMA...LA PAZ...AND WESTERN
MARICOPA COUNTY...WITH SOMEWHAT LESS CHANCES ACROSS EASTERN MARICOPA
COUNTY. THE MAIN THREAT FROM THIS STORMS WILL BE STRONG WINDS AND
BRIEF HEAVY DOWNPOURS...SINCE THEY WILL TEND TO BE FASTER MOVING
THEN THE STORMS WE SAW YESTERDAY...WITH DECENT UPPER-LEVEL SHEAR
ENHANCING TS DOWNBURSTS. THE LATEST FEW RUNS OF THE HRRR ARE
INDICATING THAT MOST OF THE ACTIVITY ACROSS SW AND SOUTH-CENTRAL
ARIZONA WILL BE OCCURRING THIS AFTERNOON AND EARLY EVENING...WITH A
SHARP REDUCTION IN TS ACTIVITY BY LATE THIS EVENING ONCE THE VORT
LOBE PASSES TO OUR NORTH.
THE AREA OF GREATEST CONCERN TODAY CONTINUES TO BE SE CA...WHERE THE
COMBINATION OF DEEPER MOISTURE AND A MORE UNSTABLE AIRMASS CLOSER TO
THE UPPER LOW CENTER IS EXPECTED TO PRODUCE WIDESPREAD TS
DEVELOPMENT...WITH HEAVY RAIN AND FLOODING TO BE THE GREATEST
ISSUE...WITH RAINFALL AMOUNTS LOCALLY IN THE 1 TO 2 INCH RANGE
POSSIBLE...AND FLASH FLOODING/URBAN AND SMALL STREAM FLOODING. ALONG
WITH THE HEAVY RAIN AND EVEN SOME SMALL HAIL...THERE COULD ALSO BE
LOCALLY STRONG WINDS AS WET MICROBURSTS REACH THE SFC. TS ACTIVITY
OVER THIS REGION IS THEN EXPECTED TO CONTINUE INTO THE EARLY EVENING
HOURS BEFORE DIMINISHING AS THE UPPER LOW MOVES OFF TO THE NORTH.
MONDAY...
THE UPPER LOW CONTINUES MOVING NORTHWARD AND WEAKENS WITH TIME. ONE
LAST WAVE IS PROGGED TO TRACK ACROSS SOUTHEAST CALIFORNIA AND INTO
ARIZONA MONDAY BUT IT WEAKENS IN THE PROCESS. MEANWHILE...DRIER AIR
FILTERS INTO THE AREA. THUS POPS FOR MONDAY TREND DOWN...ESPECIALLY
OVER SOUTHEAST CALIFORNIA.
TUESDAY THROUGH SATURDAY...
DRY SOUTHWEST FLOW ALOFT WILL LEAD TO FURTHER DECLINE OF STORM
CHANCES WITH ONLY VERY SLIGHT CHANCES OVER THE HIGHER TERRAIN EAST
OF PHOENIX TUESDAY AND WEDNESDAY. FOR THE LATTER HALF OF THE
WEEK...BOTH GFS AND ECMWF DEPICT A MOIST ADVECTION TREND AND THUS AN
EAST TO WEST TREND OF SLIGHT CHANCE POPS OVER THE FORECAST
AREA...STOPPING SHORT OF THE LOWER COLORADO RIVER VALLEY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...
SKIES WILL REMAIN MOSTLY CLEAR THROUGH MUCH OF THE MORNING HOURS
BEFORE SCATTERED CU DEVELOPS AROUND NOON. WIND DIRECTIONS WILL SHIFT
TO A SOUTHERLY DIRECTION BY THE AFTERNOON AND GENERALLY STAY MOSTLY
SOUTH TO SOUTHWESTERLY UNTIL STORM OUTFLOWS AFFECT THE AREA.
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED FROM
LATE AFTERNOON THROUGH MID EVENING AND MAY IMPACT AREA TERMINALS FOR
A BRIEF TIME. THERE WILL BE THE POTENTIAL FOR STRONG GUSTY OUTFLOW
WINDS TODAY AS DRIER AIR AND STRONGER WINDS ALOFT MOVE INTO SOUTHERN
ARIZONA BY THIS AFTERNOON.
DUE TO LOWER CONFIDENCE IN STORM TIMING AND INTENSITY...WILL
CONTINUE TO MENTION JUST VCTS IN THE PHOENIX AREA TAFS...BEGINNING
AROUND 22Z. ONCE CONVECTION DEVELOPS AND STORMS START APPROACHING
THE TERMINALS...WE WILL UPDATE TAFS AND ADD APPROPRIATE TEMPO GROUPS
FOR THUNDER.
SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA......KIPL...AND KBLH...
UPPER LEVEL LOW OVER THE NORTHERN BAJA INTO FAR SOUTHERN CALIFORNIA
COAST WILL CONTINUE TO SUPPORT ISOLATED TO SCATTERED AND
THUNDERSTORM ACTIVITY THIS AFTERNOON AND EARLY EVENING. EXPECTING
THUNDERSTORM DEVELOPMENT AFTER 21Z...AND HAVE FAIRLY HIGH CONFIDENCE
OF AFFECTING AREA TERMINALS AT LEAST FOR A BRIEF TIME LATER THIS
AFTERNOON. STRONG GUSTY WINDS IN AND AROUND THUNDERSTORMS WILL BE
THE MAIN THREAT...AND VISIBILITY MAY BE BRIEFLY AND SHARPLY REDUCED
DUE TO LOCALLY HEAVY RAIN AND OR BLOWING DUST. THE UPPER LOW WILL
PULL OUT OF THE AREA THIS EVENING LEAVING CLEARING SKIES AND WEST TO
SOUTHWESTERLY WINDS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
A DRY START TO THE FORECAST PERIOD IS EXPECTED WITH ONLY SLIGHT
CHANCES OF STORMS CONFINED TO HIGHER TERRAIN AREAS NORTH AND EAST OF
PHOENIX. THIS DRY AIR WILL LIKELY LAST THROUGH THURSDAY AND
POTENTIALLY LONGER...RESULTING IN AFTERNOON MINIMUM HUMIDITY
VALUES IN THE TEENS. A GRADUAL INCREASE IN MOISTURE SHOULD BEGIN
EITHER FRIDAY OR SATURDAY ALLOWING FOR A CHANCE OF STORMS INTO THE
SOUTH-CENTRAL ARIZONA DESERTS. HIGH TEMPERATURES WILL BE RIGHT
AROUND NORMAL FOR THE ENTIRE PERIOD.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...PERCHA/AJ
AVIATION....KUHLMAN/CB
FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION...UPDATED
NWS PHOENIX AZ
1020 AM MST SUN AUG 3 2014
.UPDATE...UPDATED AVIATION DISCUSSION.
&&
.SYNOPSIS...
EXPECT LESS CLOUDINESS THIS MORNING BEFORE THUNDERSTORM ACTIVITY
BEGINS TO DEVELOP IN THE AFTERNOON AS AN UPPER LOW CONTINUES TO
AFFECT THE REGION TODAY. FOR THE LOWER DESERTS...BEST CHANCES FOR
SHOWERS AND THUNDERSTORMS WILL BE OVER SOUTHEAST CALIFORNIA AND
PORTIONS OF SOUTHWEST ARIZONA. STORM CHANCES TREND DOWN MONDAY AS
THE LOW SHIFTS NORTHWARD AND WEAKENS. DRY SOUTHWESTERLY FLOW WILL
LIMIT STORM CHANCES TO EASTERN ARIZONA TUESDAY AND WEDNESDAY.
ANTICIPATE A GRADUAL RETURN OF STORM CHANCES FROM EAST TO WEST
DURING THE LATTER HALF OF THE WEEK.
&&
.DISCUSSION...
DRIER AIR ALOFT SPREADING IN FROM THE SOUTH BEHIND THE VORT LOBE
THAT PRODUCED STORMS OVER SOUTH-CENTRAL AZ HAVE PRETTY MUCH CLEARED
SKIES OVER MOST OF OUR CWA THIS MORNING...WITH JUST SOME LINGERING
CLOUDINESS CLOSER TO THE PARENT UPPER LOW CENTER OVER SE CA. THESE
CLEAR SKIES...COMBINED WITH ABUNDANT LOW-LEVEL MOISTURE...AND
ANOTHER WEAK VORT LOBE/JET MAX WILL LIKELY TRIGGER ANOTHER ROUND OF
TS ACTIVITY TODAY ACROSS SOUTH-CENTRAL AND SOUTHWEST AZ...WITH EVEN
BETTER CHANCES FOR TSTMS ACROSS SE CA THIS AFTERNOON AS THE MAIN
UPPER LOW MOVES NORTHWARD OVER SAN DIEGO COUNTY. GIVEN THE FACT THE
THE LATEST HRRR CONTINUES TO INDICATE TS DEVELOPMENT OVER WESTERN
MARICOPA AND YUMA COUNTIES EARLY THIS AFTERNOON JUST AHEAD OF THE
VORT LOBE...HAVE RAISED POPS WELL INTO THE CHANCE RANGE IN THE
18Z-00Z TIME FRAME ACROSS THAT REGION. THE MAIN THREAT FROM THIS
STORMS WILL BE STRONG WINDS AND BRIEF HEAVY DOWNPOURS...SINCE THEY
WILL TEND TO BE FASTER MOVING THEN THE STORMS WE SAW
YESTERDAY...WITH DECENT UPPER-LEVEL SHEAR ENHANCING TS DOWNBURSTS.
OTHER THAN THIS INCREASE IN POPS...INHERITED GRIDS ARE HOLDING UP
WELL.
&&
.PREVIOUS DISCUSSION...
TODAY...
UPPER LOW CENTERED NEAR ENSENADA THIS MORNING. SOUTHWESTERLY FLOW
ALOFT FURTHER SOUTH OVER BAJA IS SPREADING SOMEWHAT DRIER AIR INTO
ARIZONA SUCH THAT SKIES ARE CLEARING FROM THE SOUTH. THIS TREND WILL
ENABLE BETTER SURFACE HEATING TO OCCUR TODAY COMPARED TO YESTERDAY.
PROGGED CAPE VARIES CONSIDERABLY FROM ONE MODEL TO ANOTHER BUT THE
GFS AND NAM BOTH SHOW ROUGHLY 500-750 J/KG OF RELATIVELY SKINNY CAPE
OVER MUCH OF OUR FORECAST AREA. NOT SURPRISING SINCE MID LEVELS DONT
COOL MUCH. WITH DEEP SOUTHERLY FLOW...PIMA COUNTY WILL NEED TO BE
ACTIVE FOR THE SOUTH-CENTRAL ARIZONA DESERTS TO HAVE MUCH ACTIVITY.
NEARBY HIGHER TERRAIN WILL HAVE A BETTER OPPORTUNITY.
YESTERDAY...THE LOWER DESERTS OF SOUTHWEST ARIZONA AND ESPECIALLY
FAR SOUTHEAST CALIFORNIA WERE NOT VERY ACTIVE DUE TO STABLE BOUNDARY
LAYERS. TODAY MAY BE THE REVERSE. FOR ONE...THERE WILL BE LESS
CLOUDINESS WHICH WILL HELP THE BOUNDARY LAYER TO DESTABILIZE.
ALSO...THERE IS ANOTHER VORT LOBE ASSOCIATED WITH THE UPPER LOW THAT
IS PROGGED TO MOVE THROUGH TODAY AND PROVIDE SOME MODEST DYNAMICAL
FORCING. THIS WILL MAKE CONDITIONS MORE RESPONSIVE TO OUTFLOWS FROM
STORMS THAT DEVELOP OVER HIGHER TERRAIN AREAS SUCH AS FAR NORTHERN
BAJA AND SAN DIEGO COUNTY. AS A RESULT...THE HI RES MODELS GENERALLY
SHOW WESTERN PORTIONS OF THE FORECAST AREA BEING QUITE A BIT MORE
ACTIVE THAN EASTERN PORTIONS THIS AFTERNOON...EXCEPT FOR SOUTHERN
GILA COUNTY. FORECASTS REFLECT THIS AND IN FACT POPS WERE RAISED
OVER SOUTHEAST CALIFORNIA AND PORTIONS OF SOUTHWEST ARIZONA. A
LITTLE BIT OF VERTICAL WIND SHEAR AND MORE DCAPE WILL IMPROVE THE
CAPABILITY OF THE STORMS TO LAST LONGER AND PRODUCE STRONGER
DOWNDRAFTS. THE STRONGEST STORMS WILL HAVE THE POTENTIAL TO PRODUCE
BOTH VERY HEAVY RAIN AND DAMAGING WINDS.
MONDAY...
THE UPPER LOW CONTINUES MOVING NORTHWARD AND WEAKENS WITH TIME. ONE
LAST WAVE IS PROGGED TO TRACK ACROSS SOUTHEAST CALIFORNIA AND INTO
ARIZONA MONDAY BUT IT WEAKENS IN THE PROCESS. MEANWHILE...DRIER AIR
FILTERS INTO THE AREA. THUS POPS FOR MONDAY TREND DOWN...ESPECIALLY
OVER SOUTHEAST CALIFORNIA.
TUESDAY THROUGH SATURDAY...
DRY SOUTHWEST FLOW ALOFT WILL LEAD TO FURTHER DECLINE OF STORM
CHANCES WITH ONLY VERY SLIGHT CHANCES OVER THE HIGHER TERRAIN EAST
OF PHOENIX TUESDAY AND WEDNESDAY. FOR THE LATTER HALF OF THE
WEEK...BOTH GFS AND ECMWF DEPICT A MOIST ADVECTION TREND AND THUS AN
EAST TO WEST TREND OF SLIGHT CHANCE POPS OVER THE FORECAST
AREA...STOPPING SHORT OF THE LOWER COLORADO RIVER VALLEY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...
SKIES WILL REMAIN MOSTLY CLEAR THROUGH MUCH OF THE MORNING HOURS
BEFORE SCATTERED CU DEVELOPS AROUND NOON. WIND DIRECTIONS WILL SHIFT
TO A SOUTHERLY DIRECTION BY THE AFTERNOON AND GENERALLY STAY MOSTLY
SOUTH TO SOUTHWESTERLY UNTIL STORM OUTFLOWS AFFECT THE AREA.
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED FROM
LATE AFTERNOON THROUGH MID EVENING AND MAY IMPACT AREA TERMINALS FOR
A BRIEF TIME. THERE WILL BE THE POTENTIAL FOR STRONG GUSTY OUTFLOW
WINDS TODAY AS DRIER AIR AND STRONGER WINDS ALOFT MOVE INTO SOUTHERN
ARIZONA BY THIS AFTERNOON.
DUE TO LOWER CONFIDENCE IN STORM TIMING AND INTENSITY...WILL
CONTINUE TO MENTION JUST VCTS IN THE PHOENIX AREA TAFS...BEGINNING
AROUND 22Z. ONCE CONVECTION DEVELOPS AND STORMS START APPROACHING
THE TERMINALS...WE WILL UPDATE TAFS AND ADD APPROPRIATE TEMPO GROUPS
FOR THUNDER.
SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA......KIPL...AND KBLH...
UPPER LEVEL LOW OVER THE NORTHERN BAJA INTO FAR SOUTHERN CALIFORNIA
COAST WILL CONTINUE TO SUPPORT ISOLATED TO SCATTERED AND
THUNDERSTORM ACTIVITY THIS AFTERNOON AND EARLY EVENING. EXPECTING
THUNDERSTORM DEVELOPMENT AFTER 21Z...AND HAVE FAIRLY HIGH CONFIDENCE
OF AFFECTING AREA TERMINALS AT LEAST FOR A BRIEF TIME LATER THIS
AFTERNOON. STRONG GUSTY WINDS IN AND AROUND THUNDERSTORMS WILL BE
THE MAIN THREAT...AND VISIBILITY MAY BE BRIEFLY AND SHARPLY REDUCED
DUE TO LOCALLY HEAVY RAIN AND OR BLOWING DUST. THE UPPER LOW WILL
PULL OUT OF THE AREA THIS EVENING LEAVING CLEARING SKIES AND WEST TO
SOUTHWESTERLY WINDS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
A DRY START TO THE FORECAST PERIOD IS EXPECTED WITH ONLY SLIGHT
CHANCES OF STORMS CONFINED TO HIGHER TERRAIN AREAS NORTH AND EAST OF
PHOENIX. THIS DRY AIR WILL LIKELY LAST THROUGH THURSDAY AND
POTENTIALLY LONGER...RESULTING IN AFTERNOON MINIMUM HUMIDITY
VALUES IN THE TEENS. A GRADUAL INCREASE IN MOISTURE SHOULD BEGIN
EITHER FRIDAY OR SATURDAY ALLOWING FOR A CHANCE OF STORMS INTO THE
SOUTH-CENTRAL ARIZONA DESERTS. HIGH TEMPERATURES WILL BE RIGHT
AROUND NORMAL FOR THE ENTIRE PERIOD.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...PERCHA
PREVIOUS DISCUSSION...AJ
AVIATION....KUHLMAN/CB
FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS EUREKA CA
918 AM PDT SUN AUG 3 2014
.SYNOPSIS...ABOVE NORMAL TEMPERATURES WILL CONTINUE ACROSS THE
INTERIOR TODAY. INCREASING MOISTURE AND INSTABILITY WILL HEIGHTEN
THE THREAT OF THUNDERSTORMS FOR THE INTERIOR MONDAY AND TUESDAY.
MEANWHILE...THE COAST SHOULD ANTICIPATE OVERNIGHT LOW CLOUDS AND
FOG.
&&
.UPDATE...WITH LIGHT OFFSHORE FLOW OBSERVED ACROSS THE NORTH THIS
MORNING...DID A QUICK UPDATE TO EXPAND THE AREA OF SMOKE ACROSS
NORTHERN HUMBOLDT AND DEL NORTE COUNTY TO THE COAST. VISIBLE
SATELLITE IMAGERY AND HRRR AEROSOL DRY MASS PRODUCTS ALL SHOW SMOKE
FROM AREA WILDFIRES HAS MADE IT WEST TO THE COAST. THE SMOKE SHOULD
SLOWLY MIGRATE EAST FROM THE COAST THROUGH THE DAY AS WINDS SWITCH
TO THE NORTHWEST. THE REST OF THE FORECAST REMAINS UNCHANGED. STP
&&
.MARINE...9 AM...I DROPPED THE GALE FOR THE SOUTHERN OUTER WATERS
THIS MORNING AND CONVERTED IT TO A SMALL CRAFT AS MODELS SHOWING
WINDS WELL BELOW GALE. WINDS OVER THE NORTERN OUTER WATERS ARE
EXPECTED TO REMAIN STRONG WITH GALE GUSTS. UNFORTUNATELY THERE
HAVE NOT BEEN SATELLITE OR MARINE OBSERVATIOSN TO VERIFY THIS WIND
FORECAST. ON THE OTHER HAND THE WINDS OVER THE OFFSHORE WATERS
HAVE PRODUCED STEEP SEAS THAT ARE TRANSLATING INTO THE NEARSHORE
WATERS AND SEAS AT BUOY 14 ARE STEEP 6 FT AT 7 SECONDS SO HOISTED
SCA FOR THIS AREA. REST OF FORECAST LOOKS GOOD WITH FRONT
DISSPATING OVER THE EASTERN PACIFIC MONDAY INTO TUESDAY WEAKENING
THE PRESSURE GRADIENT. DEAN
&&
.PREV DISCUSSION......ISSUED AT 510 AM PDT...
SYNOPSIS...ABOVE NORMAL TEMPERATURES WILL CONTINUE ACROSS THE
INTERIOR TODAY. INCREASING MOISTURE AND INSTABILITY WILL HEIGHTEN
THE THREAT OF THUNDERSTORMS FOR THE INTERIOR MONDAY AND TUESDAY.
MEANWHILE...THE COAST SHOULD ANTICIPATE OVERNIGHT LOW CLOUDS AND
FOG.
DISCUSSION...SIGNIFICANT CHANGES WERE MADE WITH THIS FORECAST
PACKAGE. THE PERSISTENT WEATHER PATTERN THAT HAS BEEN IN PLACE
WILL REMAIN IN PLACE AT LEAST ONE MORE DAY. NORTHWEST CALIFORNIA
IS BETWEEN A RIDGE ACROSS THE INTER-MOUNTAIN WEST AND A TROUGH OFF
OF THE WEST COAST. COASTAL CLOUDS SHOULD BURN OFF TODAY AND INLAND
TEMPERATURES WILL REMAIN ABOVE NORMAL. THERE WILL BE A SLIGHT
CHANCE OF THUNDERSTORMS OVER THE TRINITY ALPS TODAY. MODELS SHOW
FAIRLY GOOD INSTABILITY. HOWEVER, MOISTURE AND SHEAR ARE MARGINAL
AND CAPPING SHOULD LIMIT SOME OF THE CONVECTION. THAT CHANGES
TONIGHT INTO MONDAY AS MODELS SHOW A WEAK UPPER LEVEL LOW FORMING
JUST TO OUR SOUTH. THIS LOW WILL MOVE SLIGHTLY TO THE NORTH LATE
MONDAY INTO TUESDAY. AS IT DOES, MONSOONAL MOISTURE WILL STREAM IN
FROM THE SOUTHEAST. THE PLENTIFUL MOISTURE AND GOOD INSTABILITY
COULD GENERATE ISOLATED TO SCATTERED THUNDERSTORMS ACROSS THE
INTERIOR MONDAY AND TUESDAY. PWATS AT OR ABOVE 1 INCH MAY ALLOW
SOME STORMS TO PRODUCE HEAVY RAIN. LIGHT TO MODERATE BULK SHEAR
AND A GENERAL LIGHT OFFSHORE ATMOSPHERIC FLOW PATTERN MAY PREVENT
THE STORMS FROM GETTING TOO STRONG. BUT IF THIS CHANGES, THEN THE
THREAT WILL CHANGE. THE CONDITIONS WON`T BE AS CONDUCIVE TO
THUNDERSTORMS ON WEDNESDAY AS THE LOW BEGINS TO MOVE TO THE EAST.
BEYOND THAT, ZONAL FLOW STARTS TO TAKE HOLD. THE INTERIOR CAN
EXPECT AT OR ABOVE NORMAL TEMPERATURES AND DRY CONDITIONS. THE
COAST CAN EXPECT TEMPERATURES NEAR NORMAL.
AVIATION...LIFR TO IFR CONDITIONS OBSERVED ALONG THE COAST THIS
MORNING WITH EXTENSIVE STRATUS ALONG BOTH THE REDWOOD AND
MENDOCINO COASTS. CONDITIONS HAVE IMPROVED SLIGHTLY TONIGHT OVER
LAST NIGHT WITH CIGS AROUND 5 OR 6 HUNDRED FEET WITH P6SM VSBYS.
EXPECT LIFR CONDITIONS TO REDEVELOP EARLY THIS MORNING AT BOTH
KCEC AND KACV BUT THEN LIFT TO VFR BY EARLY AFTERNOON MUCH LIKE
YESTERDAY. MODELS CONTINUE TO INDICATE THAT THIS WILL NOT CHANGE
MUCH OVER THE NEXT COUPLE OF DAYS. AS SUCH...HAVE CONTINUED WITH A
PERSISTENCE FORECAST. A FEW HOURS OF VFR CONDITIONS ARE POSSIBLE
ALONG THE COAST THIS AFTERNOON/EVENING BEFORE COASTAL STRATUS
EXPANDS ONCE AGAIN THIS OVERNIGHT. VFR CONDITIONS WILL PREVAIL
ACROSS THE INTERIOR. SMOKE FROM AREA WILDFIRES IS EXPECTED TO
SPREAD ACROSS MUCH OF THE CWA. MKN
MARINE...LITTLE CHANGE IN THE PATTERN WITH PERSISTENT N WINDS
CONTINUING WELL INTO THE COMING WEEK AS HIGH PRESSURE OFFSHORE
INTERACTS WITH THE INLAND THERMAL TROF. HAVE CONTINUED THE LOW END
GALE WARNING THROUGH TONIGHT FOR GUSTS. NO SHIP REPORTS OR SAT
WINDS ATTM BUT MODELS CONTINUED TO INDICATE THE TIGHTENING
GRADIENT AS EARLIER FORECAST. GRADIENT SLACKENS OFF SLIGHTLY ABOUT
TUESDAY AS DISSIPATING FRONT MOVES BY TO THE NORTH WEAKENING THE
HIGH. GRADIENT TIGHTENS BACK UP AGAIN LATER IN THE WEEK AND MAY
NEED GALE AGAIN IN OUTER WATERS.
TROPICAL SYSTEMS MOVING ACROSS THE EASTERN PACIFIC WILL GENERATE
SOME LONG PERIOD SOUTHERLY SWELL IN THE 2 FT 14-17 SECOND RANGE.
MKN
FIRE WEATHER...MONSOONAL MOISTURE STREAMING IN FROM THE SOUTHEAST
COMBINED WITH A WEAK UPPER LEVEL LOW JUST TO OUR SOUTH MAY PRODUCE
ISOLATED TO SCATTERED THUNDERSTORMS FOR SOME OF THE INLAND
DISTRICTS MONDAY AND TUESDAY. PWATS AT OR ABOVE 1 INCH MAY ALLOW
SOME STORMS TO PRODUCE HEAVY WETTING RAINS. REGARDLESS, GIVEN THE
SCATTERED THREAT OF THESE STORMS, ISSUED A FIRE WEATHER WATCH FOR
ZONE 283 ON MONDAY. MORE WATCHES MAY BE NEEDED ON TUESDAY IF THE
WEATHER PATTERN REMAINS CONDUCIVE. BUT CONFIDENCE IS NOT HIGH
ENOUGH TO ISSUE THEM WITH THIS FORECAST PACKAGE.
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
CA...FIRE WEATHER WATCH FROM MONDAY MORNING THROUGH MONDAY EVENING
CAZ004.
NORTHWEST CALIFORNIA COASTAL WATERS...
SMALL CRAFT ADVISORY UNTIL 3 AM PDT MONDAY PZZ450-455-475.
GALE WARNING UNTIL 3 AM PDT MONDAY PZZ470.
&&
$$
VISIT US AT HTTP://WWW.WEATHER.GOV/EUREKA
FOLLOW US ON FACEBOOK AND TWITTER AT:
HTTP://WWW.FACEBOOK.COM/NWSEUREKA
HTTP://WWW.TWITTER.COM/NWSEUREKA
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
621 PM EDT SUN AUG 3 2014
.SYNOPSIS...
AN UPPER LOW OVER WESTERN PENNSYLVANIA THIS AFTERNOON WILL LIFT
NORTHEAST INTO NEW ENGLAND TONIGHT. MEANWHILE, A FRONTAL BOUNDARY
WILL REMAIN POSITIONED OFF THE EAST COAST EARLY THIS WEEK. TROPICAL
STORM BERTHA IS FORECAST TO TRACK NORTHWARD OFF THE SOUTHEAST COAST
MONDAY BEFORE RE-CURVING TO THE NORTHEAST TUESDAY, WELL EAST OF THE
MID-ATLANTIC COAST. A COLD FRONT WILL MOVE THROUGH THE REGION
WEDNESDAY. THE FRONT IS EXPECTED TO STALL JUST SOUTH OF THE AREA
LATE IN THE WEEK INTO NEXT WEEKEND AS HIGH PRESSURE ATTEMPTS TO
BUILD IN FROM THE GREAT LAKES.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
AN UPPER LOW WHICH IS CURRENTLY MOVING SLOWLY ACROSS WRN/CNTRL PA
WILL WEAKEN AND MOVE NORTH OF THE REGION TONIGHT. IT HAS CAUSED
SHOWERS WITH HEAVY RAINS ACROSS WRN/CNTRL PA SO FAR. SCT SHOWERS
ARE POSSIBLE FOR THE REST OF THE AFTERNOON AND INTO THE EVENING
WITH THIS FEATURE. RIGHT NOW THE HRRR, RAP AND THE HIRES 18Z NAM
ARE TARGETING THE CLUSTERS OF SHOWERS AND THUNDER OVER MARYLAND
AND SOUTHERN PA TO MOVE EAST TOWARD THE EASTERN SHORE OF MD AND
CHESTER/BERKS COUNTIES PA. FOG IS EXPECTED TO DEVELOP
OVERNIGHT...AND WE HAVE INCLUDED AREAS OF FOG IN THE GRIDS. LOWS
TONIGHT WILL RANGE FROM THE UPPER 50S NORTH TO THE UPPER 60D
SOUTH. MET/MAV MOS TEMPS WERE USED FOR THE FCST.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
THE WEAK UPPER LOW WILL HAVE MOVED AWAY BY MON MORNING AND WITH HIGH
PRESSURE STARTING TO MOVE TOWARD THE AREA...A BETTER WEATHER DAY IS
EXPECTED. THERE WILL BE SOME FOG EARLY...BUT DRIER AIR ALOFT WILL
LEAD TO AT LEAST PARTLY SUNNY SKIES BY AFTERNOON. SCT SHOWERS WILL
PROBABLY DEVELOP DURING THE AFTERNOON...BUT COVERAGE WILL NOT BE AS
WIDESPREAD AS THE PAST FEW DAYS. TEMPERATURES WILL JUMP BACK TO
NORMAL LEVELS WITH MOSTLY MID 80S ACROSS THE AREA. WINDS WILL BE
WRLY/NWRLY AT 5 TO 10 MPH.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
LARGE-SCALE PATTERN WILL FEATURE A PERSISTENT TROUGH OVER THE ERN
CONUS THRU MUCH OF THE WEEK. SEVERAL SHORTWAVE DISTURBANCES ROTATING
AROUND THE MAIN TROUGH WILL PROVIDE THE CHANCE OF SHOWERS AND
THUNDERSTORMS THRU MIDWEEK, PARTICULARLY ON WEDNESDAY WHEN A COLD
FRONT MOVES THRU THE CWA. ALSO, DO NOT EXPECT ANY HEATWAVES TO OCCUR
ACROSS OUR REGION UNDER THIS SETUP. TEMPS WILL BE NEAR NORMAL
THROUGHOUT THE LONG-TERM PERIOD. THE WARMEST DAY EXPECTED IN THE
PERIOD IS TUESDAY, BUT MAX TEMPS IN THE MU 80S (PERHAPS REACHING
90F IN A FEW SPOTS) AND MIN TEMPS IN THE MU 60S MONDAY NIGHT AND
TUESDAY NIGHT WOULD ONLY BE AT OR A COUPLE OF DEGREES ABOVE NORMAL
FOR EARLY AUGUST.
MONDAY NIGHT SHOULD BE DRY ACROSS MOST OF THE REGION. TROPICAL STORM
BERTHA IS EXPECTED TO INTERACT WITH THE STALLED OFFSHORE BOUNDARY AS
IT TRACKS EAST OF THE OUTERBANKS. CANNOT RULE OUT A FEW SHOWERS ON
THE NRN PERIPHERY OF THE SYSTEM REACHING THE DELMARVA.
BERTHA IS FORECAST BY THE NATIONAL HURRICANE CENTER TO RE-CURVE TO
THE NORTHEAST TUESDAY AND TUESDAY NIGHT, WITH A TRACK THAT IS WELL
EAST OF THE DELMARVA/NJ COAST. MODEST LIFT PROVIDED BY AN UPSTREAM
SHORTWAVE TROUGH MAY YIELD ISO TO SCT SHOWERS/TSTMS ON TUESDAY.
CONFINED LOW CHANCE POPS TO THE SOUTHERN TIER OF THE CWA, WHERE
DIFFERENTIAL HEATING MAY PROVIDE A FOCUS FOR DIURNAL CONVECTION ON
THE NWRN PERIPHERY OF THE TROPICAL SYSTEM AND ALSO IN THE POCONOS,
WHERE CONVECTION COULD INITIATE OVER THE HIGHER TERRAIN.
A BETTER CHANCE FOR SHOWERS AND STORMS EXPECTED ON WEDNESDAY WHEN A
COLD FRONT MOVES THRU THE AREA. LATEST TREND IN THE FCST WAS TO
RAISE POPS A BIT TO 40-50 PERCENT SINCE THERE IS BETTER MODEL
AGREEMENT REGARDING THE POSITION/TIMING OF THE COLD FRONT, ULVL JET
STREAK AND THE UPPER SHORTWAVE TROUGH. IT APPEARS THAT FAVORABLE
DYNAMICS FROM THESE FEATURES WILL BECOME JUXTAPOSED OVER THE CWA FOR
A PERIOD WEDNESDAY AFTERNOON.
THE FRONT IS FORECAST TO GRADUALLY SHIFT SOUTH OF THE AREA WEDNESDAY
NIGHT BEFORE STALLING SOMEWHERE NEAR THE NC-VA BORDER LATE IN THE
WEEK. ISO SHOWERS POSSIBLE IN EXTREME NERN PA/NRN NJ THURSDAY
AFTERNOON AS COLD POOL ASSOCIATED WITH A TROUGH ALOFT PROVIDES SOME
INSTABILITY. CONVECTION WOULD BE MAINLY DIURNALLY-DRIVEN, LOW-TOPPED
AND ANY COVERAGE OF SHOWERS/STORMS SHOULD BE LOW.
MODEL SPREAD DOES INCREASE LATE IN THE PERIOD, PARTICULARLY THIS
WEEKEND IN REGARDS TO THE POSITION OF THE BOUNDARY AND THE
DEVELOPMENT OF LOPRES ALONG THAT BOUNDARY. ATTM...KEPT THE FCST
NEXT WEEKEND DRY, BUT IF MODELS CONTINUE TO TREND FARTHER
NORTHWARD, PRECIP CHANCES MAY NEED TO BE ADDED, ESPECIALLY ACROSS
THE SRN TIER.
&&
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
RATHER POOR FLYING CONDITIONS HAVE BEEN ACROSS THE AREA TODAY...MUCH
LIKE YESTERDAY. MOSTLY MVFR CIGS HAVE BEEN ACROSS THE DEL VALLEY AND
NORTH/WEST. IFR CONDITIONS WITH SOME LIGHT SHOWERS HAVE BEEN ACROSS
KMIV/KACY. CIGS HAVE BEEN SLOWLY RISING THE PAST FEW HOURS...SO SOME
VFR CONDITIONS WILL LIKELY OCCUR SHORTLY. SAT ALSO SHOWS THIN SPOTS
DEVELOPING IN THE OVC.
THE IMPROVING CONDITIONS WILL CONTINUE THRU THE EARLY EVENING BEFORE
COOLING AND FOG FORMATION IS EXPECTED. WE HAVE CONTINUED WITH THE
PREVIOUS FCST FOR THE EVENING...AND THEN FOLLOWED THE GFS LAMP AND
HIT THE FOG RATHER HARD FOR THE TAF SITES...ESPECIALLY KMIV/KACY.
THE FOG MAY NOT GET AS INTENSE...IF MORE LOW CIGS ROLL IN TONIGHT.
MONDAY...AFTER THE FOG BURNS OFF...VFR EXPECTED WITH WEST/NORTHWEST
WINDS AROUND 10 KTS BY NOON.
OUTLOOK...
MONDAY NIGHT AND TUESDAY...PREDOMINATELY VFR WITH LOW CHANCE FOR
SHRA/TSRA MAINLY SOUTH OF PHILA TERMINALS. LIGHT WINDS DURING THE
PERIOD.
TUESDAY NIGHT AND WEDNESDAY...COLD FRONT APPROACHES TUESDAY NIGHT.
CHANCE FOR SHRA/TSRA WITH HIGHEST COVERAGE OF CONVECTION EXPECTED
WEDNESDAY AFTERNOON AS THE COLD FRONT MOVES THRU. MAINLY VFR BUT
LOCAL/TEMPORARY FLIGHT RESTRICTIONS WOULD BE ANTICIPATED IN HEAVIER
ACTIVITY.
WEDNESDAY NIGHT THROUGH FRIDAY...COLD FRONT MOVES SOUTH OF THE
TERMINALS. ATTM, EXPECT A MAINLY DRY PERIOD WITH HIPRES TRYING TO
BUILD IN FROM THE GREAT LAKES.
&&
.MARINE...
RATHER SHOWERY/FOGGY CONDITIONS ACROSS THE WATERS AS A FRONT AND
WAVES OF LOW PRESSURE MOVE ALONG IT. THE FRONT WILL EDGE EASTWARD
TONIGHT BRINGING SCT SHOWERS AND LIGHT WINDS. WIND DIRECTIONS WHICH
HAVE BEEN MOSTLY NE OR E WILL SWITCH MORE WRLY/NWRLY ON MONDAY. SEAS
ON THE OCEAN WILL REMAIN MOSTLY AROUND 3 FT. OVER DEL BAY...SE WINDS
WILL BECOME NW MONDAY WITH SPEEDS 5 TO 10 KTS. AREAS OF FOG ARE
POSSIBLE TONIGHT WITH LOWER VSBYS.
OUTLOOK...
MONDAY NIGHT...NO HAZARDS EXPECTED ON THE WATERS.
TUESDAY THROUGH WEDNESDAY...TROPICAL STORM BERTHA IS EXPECTED TO
TRACK WELL EAST OF THE AREA, BUT IS FORECAST TO PRODUCE WAVES OF
3-4 FT. IF THE TRACK OF BERTHA SHIFTS CLOSER TO THE COAST, LOCALLY
HIGHER WAVES MAY REACH SCA CRITERIA. LONG-PERIOD SWELLS OF 10-13
S ARE CURRENTLY FORECAST FOR TUESDAY AND WEDNESDAY.
WEDNESDAY NIGHT THROUGH FRIDAY...NO MARINE HEADLINES ARE ANTICIPATED.
&&
.RIP CURRENTS...
THERE REMAINS SOME ENHANCED WAVE ACTION ALONG THE COAST THIS
AFTERNOON. CONTINUE TO HIGHLIGHT A MODERATE RISK OF RIP CURRENTS
THROUGH THIS EVENING.
LONG PERIOD SWELLS FROM TROPICAL STORM BERTHA MAY AFFECT THE
COASTS OF DELAWARE AND NEW JERSEY FROM LATE MONDAY INTO WEDNESDAY.
THE SWELLS COULD BRING AN ENHANCED THREAT FOR DANGEROUS RIP
CURRENTS DURING THIS TIME.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KLEIN
NEAR TERM...GAINES/O`HARA
SHORT TERM...O`HARA
LONG TERM...KLEIN
AVIATION...KLEIN/O`HARA
MARINE...KLEIN/O`HARA
RIP CURRENTS...KLEIN/O`HARA
AREA FORECAST DISCUSSION
NWS MIAMI FL
252 PM EDT SUN AUG 3 2014
.NEAR TERM...(THIS AFTERNOON)
THE HEAVY LINE OF SHOWERS/TSTMS THAT MOVED ASHORE EARLY THIS
AFTERNOON HAS WEAKENED AND DISSIPATED...MAINLY DUE TO THE MORE
STABLE EAST COAST WHERE TEMPERATURES HAVE REMAINED STEADY IN THE
LOWER 80S FROM THE EXTENSIVE CLOUD COVERAGE ASSOCIATED WITH THE
OFFSHORE CONVECTION EARLIER. FARTHER INLAND...ADDITIONAL SHOWERS
HAVE BEGUN TO DEVELOP WHERE A BETTER SOURCE OF INSTABILITY EXISTS
(TEMPERATURES HAVE ALREADY REACHED THE UPPER 80S TO 90 DEG RANGE).
THE LATEST HRRR HAS PICKED UP ON THESE TRENDS AND HAS BACKED OFF
ON THE EARLIER SUGGESTED EAST COAST ACTIVITY LATER THIS
AFTERNOON/EARLY EVENING SHOWING MOSTLY STRATIFIED PRECIP FOR THE
SE FL COAST (OR LIGHT RAIN WITH EMBEDDED HEAVIER SHOWERS/TSTMS
ALONG THE EAST COAST) THROUGH THE AFTERNOON HOURS. HOWEVER...THE
LAKE REGION INCLUDING PALM BEACH COUNTY COULD OBSERVE SOME
HEAVIER AFTERNOON SHOWERS/TSTMS.
.SHORT TERM...(TONIGHT-TUESDAY NIGHT)
THE LATEST SHORT-RANGE MODEL GUIDANCE REMAINS CONSISTENT FROM CYCLE
TO CYCLE AND INDICATES THE WET PATTERN PERSISTING INTO THE UPCOMING
WEEK AS A SURFACE TROUGH OF LOW PRESSURE AND UPPER TROUGH CONTINUE
TO INFLUENCE THE LOCAL WEATHER PATTERN. AN ASCAT PASS THIS
AFTERNOON SHOWED TS BERTHA CENTERED NEAR THE SOUTHEASTERN BAHAMA
ISLANDS. THE LATEST ADVISORY INDICATES BERTHA TURNING NORTHWARD
AND REMAINING JUST EAST OF THE BAHAMAS THROUGH MONDAY AS IT PASSES
(SHOULD NOT HAVE ANY DIRECT IMPACT ON THE LOCAL AREA). THE LATEST
GUIDANCE INDICATES THE SFC TROUGH OVERHEAD THAT IS IMPACTING THE
LOCAL WEATHER SLOWLY LIFTING NWD INTO MONDAY...WHICH WILL
TRANSLATE TO SW LOW-LEVEL FLOW WITH THE RIDGE AXIS ORIENTED E-W
SOUTH OF THE AREA OVER THE STRAITS. THIS LOW-LEVEL FLOW COMBINED
WITH THE AFOREMENTIONED DEEP LAYER MOISTURE (MODEL PWAT VALUES
RANGING FROM 2- 2.3" MONDAY-TUESDAY EVENING) COULD TRANSLATE TO A
POTENTIAL HEAVY RAINFALL/FLOODING CONCERN OVER PORTIONS OF THE
LOCAL AREA PERIODICALLY...ESPECIALLY WITH THE RECENT ACTIVITY AND
THE ALREADY SATURATED GROUNDS. THE LATEST RAINFALL ACCUMULATION
PROJECTION INDICATES 1.5 TO 2.5" WIDESPREAD AMOUNTS. MUCH HIGHER
LOCALIZED AMOUNTS WHERE ANY ACTIVITY BECOMES FOCUSED FOR A PERIOD
OF TIME WILL REMAIN POSSIBLE EACH DAY. THE SURFACE FLOW IS
PROJECTED TO REMAIN LIGHT ENOUGH FOR AN EAST COAST SEA BREEZE TO
DEVELOP EACH DAY...WHICH TYPICALLY RESULTS IN THE AFTERNOON
CONVECTION SETTING UP AND FAVORING THE EAST COAST.
HOWEVER...SIMILAR TO TODAY...STABILITY COULD PLAY A ROLE HERE AND
END UP REDUCING THE OVERALL HEAVY RAIN/FLOODING CONCERNS...IF THE
OVERCAST AND RELATIVELY COOL CONDITIONS ARE REALIZED THROUGH THE
AFTERNOON PERIODS AGAIN MONDAY AND TUESDAY.
.LONG TERM (WEDNESDAY-WEEKEND)...
THE LATEST EXTENDED GUIDANCE CONTINUES TO SUGGEST A RETURN OF A MORE
TYPICAL SUMMER-LIKE PATTERN ACROSS THE REGION THROUGH THE SECOND
HALF OF THE WEEK AND INTO THE WEEKEND AS A DEEP LAYER RIDGE BUILDS
BACK OVERHEAD. AT THIS TIME...IT APPEARS WEDNESDAY COULD BE THE
TRANSITION DAY...WHICH WOULD MEAN ANOTHER WET AFTERNOON WITH A
SUFFICIENT AMOUNT OF DEEP LAYER MOISTURE AND LIGHT SW LOW-LEVEL FLOW
TO FOCUS THE AFTERNOON ACTIVITY TOWARD THE EAST COAST.
&&
.AVIATION...
MOST OF THE CONVECTION HAS DISSIPATED ACROSS THE NEAR
SHORE ATLANTIC WATERS THIS AFTERNOON AFTER ENCOUNTERING A MORE
STABLE AIR MASS. ONLY AREAS OF LIGHT TO MODERATE SHOWERS REMAIN
WHICH SHOULD BE COVERED WELL WITH VCSH. LATEST HRRR KEEPS SHOWERS
ACROSS THE EAST COAST THROUGH THE EARLY EVENING WITH CONTINUED
SOUTHEAST TO SOUTHERLY WINDS. ANY REMAINING CONVECTION SHOULD STAY
ACROSS THE INTERIOR POSSIBLY AFFECTING KAPF. LEFT VCTS MENTION
THERE UNTIL 01Z.
&&
.MARINE...
TROPICAL STORM BERTHA IS FORECAST TO REMAIN WELL EAST OF THE SOUTH
FLORIDA MARINE AREAS AS IT TURNS NORTH EAST OF THE BAHAMAS LATE
TONIGHT THROUGH MONDAY. WINDS ARE FORECAST TO REMAIN LIGHT AND SHIFT
TO THE SOUTHWEST THROUGH THE EARLY PORTION OF THE WEEK. SCATTERED
SHOWERS AND STORMS COULD LEAD TO GUSTY WINDS AND LOCALLY CHOPPIER
CONDITIONS EACH DAY ALONG WITH REDUCED VISIBILITIES.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 76 90 77 92 / 50 70 40 60
FORT LAUDERDALE 77 90 80 92 / 50 70 40 50
MIAMI 77 90 79 91 / 50 70 40 50
NAPLES 77 90 76 91 / 30 50 60 50
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AVIATION...10/CD
REST OF DISCUSSION....85/AG
AREA FORECAST DISCUSSION...UPDATED
NWS DES MOINES IA
106 PM CDT SUN AUG 3 2014
.UPDATE...
ISSUED AT 1101 AM CDT SUN AUG 3 2014
A FEW TWEAKS WITH THE MORNING UPDATE...MAINLY DUE TO PRECIP
TRENDS. RAP SEEMS TO DEPICT SOME SUBSIDENCE BEHIND DEPARTING WEAK
CONVECTIVE CLUSTERS AND ELEVATED KINEMATICALLY DRIVEN MN
CONVECTION SHOULD MOVE MORE EAST THAN SOUTH. ALTHOUGH CAP IS
ERODING...SURFACE CONVERGENCE IS WEAK SO DO NOT MUCH SURFACE BASED
POTENTIAL. HI RES MODELS SUGGEST THAT AS WELL SO HAVE CAPPED POPS
AT SLIGHTS/ISOLATED WORDING. LITTLE CHANGE TO TEMPS OUTSIDE OF
LOWERING E CENTRAL A TOUCH WHERE RAIN AND CLOUDS LINGERED.
&&
.SHORT TERM /TODAY/...
ISSUED AT 311 AM CDT SUN AUG 3 2014
AIRMASS MORE UNSTABLE THIS MORNING THAN THE PAST SEVERAL DAYS AS AN
EXTENSION OF COLORADO LOW PRESSURE HAS REACHED INTO SOUTH CENTRAL
NEBRASKA AND HAS HELPED VEER THE LOW LEVEL JET INTO THE MID MISSOURI
VALLEY. UPPER PV ANOMALY IS PASSING ACROSS CENTRAL IOWA CURRENTLY
WITH THE MID LEVEL SHORTWAVE SLIGHTLY LAGGING. THE OVERALL RESULT IS
A THUNDERSTORM COMPLEX MOVING SOUTHEAST ACROSS SOUTHWEST IA WITH
MORE SPORADIC DEVELOPMENT NORTH AND EAST OF THIS REGION. THE
ACTIVITY SHOULD DIMINISH IN AREAL COVERAGE AS THE AFOREMENTIONED
UPPER LEVEL ENERGY PASSES TO THE SOUTHEAST LATER THIS MORNING.
ANOTHER SHORTWAVE EMBEDDED IN THE NORTHWEST FLOW WILL APPROACH
NORTHERN IOWA BY MID TO LATE AFTERNOON AND IS EXPECTED TO ARRIVE
WITH A CONVECTIVELY UNSTABLE AIRMASS IN PLACE WITH DIURNAL HEATING
OCCURRING. THIS SYSTEM SHOULD FORCE ENOUGH VERTICAL ASCENT TO
TRIGGER SCATTERED THUNDERSTORMS BY 00Z. THESE STORMS WILL BRING AN
ATTENDANT LARGE HAIL THREAT WITH THE STRONGEST UPDRAFTS AS MUCAPES
APPROACH 2000 J/KG THIS AFTERNOON ALONG WITH MODEST DEEP LAYER SHEAR
NEAR 25 KTS.
.LONG TERM /TONIGHT THROUGH SATURDAY/...
ISSUED AT 311 AM CDT SUN AUG 3 2014
FORECAST CONCERN FOR EXTENDED WILL CONTINUE TO REVOLVE AROUND
PRECIPITATION CHANCES...WITH LOW CONFIDENCE IN PRECIPITATION
CHANCES FOR BEGINNING OF PERIOD BEFORE MID WEEK SYSTEM PUSHES
THROUGH.
NORTHWESTERLY FLOW WILL REMAIN IN PLACE ACROSS IOWA FOR THE
BEGINNING OF THE PERIOD AS RIDGE REMAINS ACROSS ROCKIES. WITH
GENERALLY WEAK SURFACE FLOW...PRECIPITATION CHANCES WILL COME AS
SEVERAL WAVES PUSH SOUTHEAST THROUGH UPPER LEVEL FLOW.
FOR TONIGHT...MODELS HAVE BEGUN TO PULL WAVE FURTHER SOUTH TO NEAR
MO/IA BORDER. IN ADDITION...GIVEN BEST FORCING ACROSS FAR
SOUTHWESTERN IOWA...HAVE PULLED POPS FURTHER SOUTH. ISENTROPIC
ANALYSIS SHOWS BEST MOISTURE ALSO IN THIS AREA...AND MAY BE TOO
LOW ON POPS IN SOUTHERN CWA. AS WAVE PUSHES EASTWARD WILL SEE
CHANCES FOR PRECIPITATION SPREADING ACROSS THE CWA. ANTICIPATE
PRECIPITATION TO DIMINISH INTO THE LATE MORNING HOURS MONDAY
BEFORE ADDITIONAL ROUNDS OF SCATTERED THUNDERSTORMS ARE POSSIBLE
MONDAY AFTERNOON WITH DIURNAL HEATING. AGAIN...LIMITED FORCING FOR
PRECIPITATION THOUGH BEST INSTABILITY INDICATED IN THE EAST AND
NORTH AND HAVE INCREASED POPS THERE. DECENT INSTABILITY WITH
LACKING SHEAR MAY ALLOW FOR A FEW STRONG STORMS MONDAY AFTERNOON.
ADDITIONAL WAVE WILL DROP SOUTH INTO IOWA FOR MONDAY
NIGHT...THOUGH AGAIN MODELS HAVE COME INTO BETTER ALIGNMENT WITH
FURTHER SOUTH SOLUTION...AND HAVE TRENDED POPS SOUTH. MAIN SYSTEM
FOR EXTENDED WILL BEGIN TO INFLUENCE AREA LATE TUESDAY AS MUCH
STRONGER WAVE PUSHES SOUTH INTO IOWA. MODELS HAVE AGAIN COME INTO
BETTER AGREEMENT WITH THIS SYSTEM...TRENDING TOWARDS THE ECMWF
SOLUTION. BEST CHANCES FOR WIDESPREAD...AND POTENTIALLY
HEAVY...RAIN WILL COME TUESDAY INTO WEDNESDAY AS SYSTEM PUSHES
THROUGH. HOWEVER...HIGH PRESSURE ACROSS NORTHERN PLAINS WILL
IMPACT HOW FAR NORTH AND EAST PRECIPITATION FROM SYSTEM GETS.
ATTM...HAVE KEPT POPS WIDESPREAD ACROSS CWA...THOUGH MAY NEED TO
BE SCALED IF SYSTEM PULLS FURTHER WEST. THIS SYSTEM WILL BRIEFLY
BREAK DOWN ROCKIES RIDGE...AND ALLOW FOR COOLER
TEMPERATURES THROUGH WEEKS END...BEFORE LARGE UPPER LEVEL LOW
PRESSURE SYSTEM WILL PUSH ACROSS SOUTHERN CANADA WITH BOUNDARY
INTO IOWA...WHICH WILL ALLOW FOR ADDITIONAL CHANCES FOR
PRECIPITATION THROUGH THE END OF THE PERIOD...THOUGH AGAIN HAVE
LOWER CONFIDENCE IN TIMING AND LOCATION OF LATER PERIOD
PRECIPITATION AS MODELS AGAIN DO NOT HAVE GOOD AGREEMENT ON
PRECIPITATION WITH GFS FASTER THAN ECMWF.
&&
.AVIATION...03/18Z
ISSUED AT 106 PM CDT SUN AUG 3 2014
VFR CONDITIONS ARE ANTICIPATED THROUGH THE EVENING. OUTLOOK FOR
CONVECTION HAS DIMINISHED SO MENTION HAS BEEN REMOVED DUE TO
LITTLE PREDICTABILITY. MAIN CONCERN MAY BE VSBY TRENDS OVERNIGHT.
ALTHOUGH RESTRICTIONS DID NOT OCCUR LAST NIGHT...MOS GUIDANCE
CONSENSUS SUGGESTS IFR/LIFR VSBYS BEFORE SUNRISE. DEWPOINTS HAVE
RISEN A FEW DEGREES SINCE YESTERDAY WITH LIGHT WINDS AGAIN AND
PATCHY MORNING RAINS SO SOME RESTRICTIONS ARE POSSIBLE. HAVE NOT
GONE ALL IN YET...BUT DID MENTION MVFR/VFR VSBYS FOR A START.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...SMALL
SHORT TERM...DONAVON
LONG TERM...AWB
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1102 AM CDT SUN AUG 3 2014
.UPDATE...
ISSUED AT 1101 AM CDT SUN AUG 3 2014
A FEW TWEAKS WITH THE MORNING UPDATE...MAINLY DUE TO PRECIP
TRENDS. RAP SEEMS TO DEPICT SOME SUBSIDENCE BEHIND DEPARTING WEAK
CONVECTIVE CLUSTERS AND ELEVATED KINEMATICALLY DRIVEN MN
CONVECTION SHOULD MOVE MORE EAST THAN SOUTH. ALTHOUGH CAP IS
ERODING...SURFACE CONVERGENCE IS WEAK SO DO NOT MUCH SURFACE BASED
POTENTIAL. HI RES MODELS SUGGEST THAT AS WELL SO HAVE CAPPED POPS
AT SLIGHTS/ISOLATED WORDING. LITTLE CHANGE TO TEMPS OUTSIDE OF
LOWERING E CENTRAL A TOUCH WHERE RAIN AND CLOUDS LINGERED.
&&
.SHORT TERM /TODAY/...
ISSUED AT 311 AM CDT SUN AUG 3 2014
AIRMASS MORE UNSTABLE THIS MORNING THAN THE PAST SEVERAL DAYS AS AN
EXTENSION OF COLORADO LOW PRESSURE HAS REACHED INTO SOUTH CENTRAL
NEBRASKA AND HAS HELPED VEER THE LOW LEVEL JET INTO THE MID MISSOURI
VALLEY. UPPER PV ANOMALY IS PASSING ACROSS CENTRAL IOWA CURRENTLY
WITH THE MID LEVEL SHORTWAVE SLIGHTLY LAGGING. THE OVERALL RESULT IS
A THUNDERSTORM COMPLEX MOVING SOUTHEAST ACROSS SOUTHWEST IA WITH
MORE SPORADIC DEVELOPMENT NORTH AND EAST OF THIS REGION. THE
ACTIVITY SHOULD DIMINISH IN AREAL COVERAGE AS THE AFOREMENTIONED
UPPER LEVEL ENERGY PASSES TO THE SOUTHEAST LATER THIS MORNING.
ANOTHER SHORTWAVE EMBEDDED IN THE NORTHWEST FLOW WILL APPROACH
NORTHERN IOWA BY MID TO LATE AFTERNOON AND IS EXPECTED TO ARRIVE
WITH A CONVECTIVELY UNSTABLE AIRMASS IN PLACE WITH DIURNAL HEATING
OCCURRING. THIS SYSTEM SHOULD FORCE ENOUGH VERTICAL ASCENT TO
TRIGGER SCATTERED THUNDERSTORMS BY 00Z. THESE STORMS WILL BRING AN
ATTENDANT LARGE HAIL THREAT WITH THE STRONGEST UPDRAFTS AS MUCAPES
APPROACH 2000 J/KG THIS AFTERNOON ALONG WITH MODEST DEEP LAYER SHEAR
NEAR 25 KTS.
.LONG TERM /TONIGHT THROUGH SATURDAY/...
ISSUED AT 311 AM CDT SUN AUG 3 2014
FORECAST CONCERN FOR EXTENDED WILL CONTINUE TO REVOLVE AROUND
PRECIPITATION CHANCES...WITH LOW CONFIDENCE IN PRECIPITATION
CHANCES FOR BEGINNING OF PERIOD BEFORE MID WEEK SYSTEM PUSHES
THROUGH.
NORTHWESTERLY FLOW WILL REMAIN IN PLACE ACROSS IOWA FOR THE
BEGINNING OF THE PERIOD AS RIDGE REMAINS ACROSS ROCKIES. WITH
GENERALLY WEAK SURFACE FLOW...PRECIPITATION CHANCES WILL COME AS
SEVERAL WAVES PUSH SOUTHEAST THROUGH UPPER LEVEL FLOW.
FOR TONIGHT...MODELS HAVE BEGUN TO PULL WAVE FURTHER SOUTH TO NEAR
MO/IA BORDER. IN ADDITION...GIVEN BEST FORCING ACROSS FAR
SOUTHWESTERN IOWA...HAVE PULLED POPS FURTHER SOUTH. ISENTROPIC
ANALYSIS SHOWS BEST MOISTURE ALSO IN THIS AREA...AND MAY BE TOO
LOW ON POPS IN SOUTHERN CWA. AS WAVE PUSHES EASTWARD WILL SEE
CHANCES FOR PRECIPITATION SPREADING ACROSS THE CWA. ANTICIPATE
PRECIPITATION TO DIMINISH INTO THE LATE MORNING HOURS MONDAY
BEFORE ADDITIONAL ROUNDS OF SCATTERED THUNDERSTORMS ARE POSSIBLE
MONDAY AFTERNOON WITH DIURNAL HEATING. AGAIN...LIMITED FORCING FOR
PRECIPITATION THOUGH BEST INSTABILITY INDICATED IN THE EAST AND
NORTH AND HAVE INCREASED POPS THERE. DECENT INSTABILITY WITH
LACKING SHEAR MAY ALLOW FOR A FEW STRONG STORMS MONDAY AFTERNOON.
ADDITIONAL WAVE WILL DROP SOUTH INTO IOWA FOR MONDAY
NIGHT...THOUGH AGAIN MODELS HAVE COME INTO BETTER ALIGNMENT WITH
FURTHER SOUTH SOLUTION...AND HAVE TRENDED POPS SOUTH. MAIN SYSTEM
FOR EXTENDED WILL BEGIN TO INFLUENCE AREA LATE TUESDAY AS MUCH
STRONGER WAVE PUSHES SOUTH INTO IOWA. MODELS HAVE AGAIN COME INTO
BETTER AGREEMENT WITH THIS SYSTEM...TRENDING TOWARDS THE ECMWF
SOLUTION. BEST CHANCES FOR WIDESPREAD...AND POTENTIALLY
HEAVY...RAIN WILL COME TUESDAY INTO WEDNESDAY AS SYSTEM PUSHES
THROUGH. HOWEVER...HIGH PRESSURE ACROSS NORTHERN PLAINS WILL
IMPACT HOW FAR NORTH AND EAST PRECIPITATION FROM SYSTEM GETS.
ATTM...HAVE KEPT POPS WIDESPREAD ACROSS CWA...THOUGH MAY NEED TO
BE SCALED IF SYSTEM PULLS FURTHER WEST. THIS SYSTEM WILL BRIEFLY
BREAK DOWN ROCKIES RIDGE...AND ALLOW FOR COOLER
TEMPERATURES THROUGH WEEKS END...BEFORE LARGE UPPER LEVEL LOW
PRESSURE SYSTEM WILL PUSH ACROSS SOUTHERN CANADA WITH BOUNDARY
INTO IOWA...WHICH WILL ALLOW FOR ADDITIONAL CHANCES FOR
PRECIPITATION THROUGH THE END OF THE PERIOD...THOUGH AGAIN HAVE
LOWER CONFIDENCE IN TIMING AND LOCATION OF LATER PERIOD
PRECIPITATION AS MODELS AGAIN DO NOT HAVE GOOD AGREEMENT ON
PRECIPITATION WITH GFS FASTER THAN ECMWF.
&&
.AVIATION...03/12Z
ISSUED AT 645 AM CDT SUN AUG 3 2014
ISOLD TO SCT THUNDERSTORMS ARE POSSIBLE DURING THE PERIOD AT ALL
SITES. BEST POTENTIAL EARLY IN THE PERIOD WILL BE NEAR KOTM THEN
KALO AND KMCW LATER THIS AFTERNOON. MVFR CIGS POSSIBLE IN VICINITY
OF THUNDERSTORMS OTHERWISE VFR WILL PERSIST. LIGHT SOUTHERLY
WINDS WILL CONTINUE TODAY.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...SMALL
SHORT TERM...DONAVON
LONG TERM...AWB
AVIATION...DONAVON
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
351 PM CDT Sun Aug 3 2014
...UPDATE TO LONG TERM...
.SHORT TERM...(This evening through Monday)
ISSUED AT 333 PM CDT SUN AUG 3 2014
This mornings convective allowing models allowed some room for
convection to develop once again just north of the I-70 corridor and
be driven southeast by the man flow, much like last evening. So far
this afternoon the area of enhanced cu development across northwest
Kansas has not shown signs of stronger shower or storm development
although the GLD 88D was indicating rain in the HCA. We will
continue to carry less than 20 PoPs trough the end of the afternoon
and early evening to see how this evolves, especially given the
increasingly robust HRRR model drives a few storms into Rush and
Stafford counties.
For the rest of the period including tonight into tomorrow, we
followed the NAM and Raw Model Blend which seemed to do the best job
collectively with temperatures and surface winds for yesterday.
little overall change in airmass will take place with the upper
ridge settling slightly farther east.
.LONG TERM...(Monday night through Sunday)
ISSUED AT 350 PM CDT SUN AUG 3 2014
Drier conditions will persist across western Kansas through early
Tuesday afternoon as an upper level ridge axis shifts eastward across
the Western High Plains. Medium range models then indicate the ridge
breaking down late Tuesday as a series of H5 vort maxima associated
with a shortwave eject out of the Rockies into the high plains of
western Nebraska and western Kansas. A developing lee side trough
will strengthen as the shortwave approaches while low/mid level
moisture continues to pool slowly across central and portions of
western Kansas. This will set the stage for possible thunderstorm
development across portions of southwest and central Kansas Tuesday
evening into Wednesday. Although low/mid level lapse rates will
steepen through the afternoon period Tuesday, NAM/GFS model
soundings show very little instability in regards to available CAPE
with values well under 100 J/KG. This will likely hinder storm
development through much of the afternoon with chances increasing
Tuesday evening as CAPE begins to rise. Although less than
favorable, a slightly strengthened flow aloft along with decent
directional shear may be enough to support stronger thunderstorms
with gusty winds the primary threat.
Precip chances will shift eastward across western into central
Kansas Wednesday as the surface trough migrates through.
Thunderstorms will be possible again into Thursday as H5 vort
maxima continue to move out of the Rockies into the Western High
Plains. However, better chances will be more to the north across
west central and central Kansas in association with the stronger
flow. Seasonal temperatures will continue through Thursday as a
south to southeasterly flow prevails through much of the period.
This will reinforce the warm air mass already in place across
western Kansas keeping highs up into the 90s(F) each day through
the end of the week.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
ISSUED AT 1237 PM CDT SUN AUG 3 2014
A very slowly changing surface pressure pattern marked by relative
high pressure over Missouri will result in light winds veering south
with time through tonight. VFR - clear conditions are expected with
only a very small chance of surface convergence/diurnally forced
high based CB`s between around 22-and 02 near and east of KHYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 65 92 69 94 / 0 0 0 10
GCK 63 92 68 94 / 0 0 0 20
EHA 64 91 67 95 / 0 0 0 10
LBL 65 93 69 96 / 0 0 0 20
HYS 67 95 70 93 / 20 0 0 10
P28 66 93 69 94 / 0 0 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Russell
LONG TERM...JJohnson
AVIATION...Russell
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
335 PM CDT Sun Aug 3 2014
...updated short term...
.SYNOPSIS...
ISSUED AT 333 PM CDT SUN AUG 3 2014
Weak anticyclonic surface flow was in place over the Kansas High
Plains with a weak moisture gradient from west to east. Surface dew
points were in the lower 40s in the far west to around 60 degrees
from Stafford country through Medicine lodge. Weak downslope
through the Smoky Hills region likely added a few degrees to
temperatures this afternoon, reaching the low 90s at Hays. The upper
ridging pattern in place and light winds also were contributing to
a significant lack of bulk shear across the area. The higher dew
points of central Kansas contributed to higher CAPE values up to
around 1500 j/kg in the south central Kansas counties. A weak
surface convergence zone across northwest Kansas and sn Nebraska was
a zone of current ongoing cu development
&&
.SHORT TERM...(This evening through Monday)
ISSUED AT 333 PM CDT SUN AUG 3 2014
This mornings convective allowing models allowed some room for
convection to develop once again just north of the I-70 corridor and
be driven southeast by the man flow, much like last evening. So far
this afternoon the area of enhanced cu development across northwest
Kansas has not shown signs of stronger shower or storm development
although the GLD 88D was indicating rain in the HCA. We will
continue to carry less than 20 PoPs trough the end of the afternoon
and early evening to see how this evolves, especially given the
increasingly robust HRRR model drives a few storms into Rush and
Stafford counties.
For the rest of the period including tonight into tomorrow, we
followed the NAM and Raw Model Blend which seemed to do the best job
collectively with temperatures and surface winds for yesterday.
little overall change in airmass will take place with the upper
ridge settling slightly farther east.
.LONG TERM...(Monday through Saturday)
ISSUED AT 317 AM CDT SUN AUG 3 2014
The upper level ridge currently situated over the Rockies and
adjacent High Plains will flatten out somewhat through the early
part of the extended period. Mainly dry weather will persist across
western Kansas through Tuesday. Chances for showers and
thunderstorms will increase from late Tuesday through Wednesday as
an upper level disturbance lifts out of the Desert Southwest through
the central Rockies and Plains through mid week. Model soundings are
not overly unstable but a favorable warm advection pattern develops
which should enhance upward vertical motion and thunderstorm
development. Thursday should see a lull in precipitation chances as
the energy from the first disturbance moves east of the region and
upper level ridging briefly builds back into the central High
Plains. The models show additional disturbances moving east through
the Rockies into the northern and central Plains later in the week.
Tough to say how much energy with these systems will move over
Kansas as the stronger upper level westerly flow will reside over
the northern portions of the country later in the week but for now,
the chance/slight chance pops in the extended initialization look
reasonable.
High temperatures should be in the low to mid 90s through the period
which is near seasonal normals for early August.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
ISSUED AT 1237 PM CDT SUN AUG 3 2014
A very slowly changing surface pressure pattern marked by relative
high pressure over Missouri will result in light winds veering south
with time through tonight. VFR - clear conditions are expected with
only a very small chance of surface convergence/diurnally forced
high based CB`s between around 22-and 02 near and east of KHYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 65 92 69 94 / 0 0 0 10
GCK 63 92 68 94 / 0 0 0 20
EHA 64 91 67 95 / 0 0 0 10
LBL 65 93 69 96 / 0 0 0 20
HYS 67 95 70 93 / 20 0 0 10
P28 66 93 69 94 / 0 0 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...Russell
SHORT TERM...Russell
LONG TERM...Gerard
AVIATION...Russell
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
402 PM CDT SUN AUG 3 2014
.DISCUSSION...
FRONTAL BOUNDARY AND WEAK SURFACE LOW THAT WERE STALLED ACROSS THE
FORECAST AREA HAVE DISSIPATED. SHOWERS AND THUNDERSTORMS HAVE TAKEN
A LITTLE LONGER TO GET GOING TODAY BUT RADAR SHOWS QUITE A FEW
SHOWERS AND THUNDERSTORMS DEVELOPING ALONG THE EASTERN AND WESTERN
FRINGES OF THE CWA WHERE DEWPOINTS ARE GENERALLY IN THE LOWER TO MID
70S VS UPPER 60S ELSEWHERE. STORM MOTION PER THIS MORNINGS UPPER AIR
SOUNDING IS A WHOPPING 1 KT. SO DONT EXPECT ANY SHOWER OVERHEAD TO
MOVE AWAY FAST IN ANY WAY SHAPE OR FORM. IT WILL HAVE TO BASICALLY
RAIN ITSELF OUT. MINOR STREET FLOODING WILL BE POSSIBLE UNDER MORE
INTENSE CELLS. HRRR ONCE AGAIN OVER DOING COVERAGE TODAY BUT
STILL BELIEVE THE DIURNAL TREND ITS SHOWING WITH MOST ACTIVITY
DISSIPATED BY 04Z.
ECMWF AND GFS MODELS SHOW UPPER LEVEL TROUGH THAT CURRENTLY EXTENDS
SOUTH ACROSS THE ENTIRE GULF COAST WILL GRADUALLY LIFT NORTHEAST THE
REMAINDER OF THIS WEEK AND INTO NEXT WEEKEND WHILE RIDGE CENTERED TO
THE WEST BUILDS EAST. THIS ALONG WILL LEAVE CONVECTION DEVELOP TO
JUST DAYTIME HEATING AND THUS A RETURN TO MORE TYPICAL SUMMERTIME
SHOWERS AND STORMS. COVERAGE WILL REMAIN IN THE 20-40 PERCENT RANGE.
TEMPERATURES TO REMAIN AT OR SLIGHTLY BELOW NORMAL UNTIL AT LEAST
THE LATTER HALF OF THE WEEK.
MEFFER
&&
.AVIATION...
VFR CONDITIONS WILL GENERALLY PREVAIL AT THE TERMINALS THROUGH THE
TAF FORECAST PERIOD. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS
WILL BE POSSIBLE...PRIMARILY DURING THE REMAINDER OF THE AFTERNOON
HOURS TODAY. 11
&&
.MARINE...
WEAK HIGH PRESSURE WILL BUILD OVER THE NORTH GULF DURING THE WEEK
RESULTING IN GENERALLY LIGHT AND AT TIMES VARIABLE WINDS AND LOW
SEAS. 11
&&
.DECISION SUPPORT...
DSS CODE...GREEN.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TO HIGH RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE.
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 71 91 71 90 / 20 30 20 30
BTR 72 90 72 91 / 20 30 20 30
ASD 72 91 72 88 / 30 40 20 30
MSY 76 90 76 89 / 30 40 20 30
GPT 76 90 77 92 / 30 40 20 30
PQL 71 91 72 90 / 30 40 20 30
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
139 PM EDT SUN AUG 3 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 330 AM EDT SUN AUG 3 2014
A WEAK HIGH PRESSURE RIDGE WILL BRING FAIR WEATHER TODAY WITH
SEASONABLY WARM TEMPERATURES. A WEAK COLD FRONT WILL BRING
SCATTERED SHOWERS AND THUNDERSTORMS MONDAY INTO MONDAY EVENING.
A FEW SHOWERS AND STORMS WILL LINGER MAINLY NEAR TO SOUTH OF
INTERSTATE 96 TUESDAY BEFORE DRY WEATHER RETURNS WEDNESDAY THROUGH
THE REMAINDER OF THE WEEK. TEMPERATURES WILL AVERAGE RATHER CLOSE
TO NORMAL THROUGH THE UPCOMING WEEK.
&&
.UPDATE...
ISSUED AT 1046 AM EDT SUN AUG 3 2014
BUMPED UP AFTERNOON TEMPERATURES A DEGREE OR TWO...OTHERWISE NO
CHANGES ON MORNING UPDATE.
LOOKING AT TOMORROW...INITIAL THINKING IS THAT THERE WILL BE A
GOOD BIT OF EVENING SHOWER / THUNDERSTORM ACTIVITY SLOWLY WORKING
NORTH TO SOUTH AHEAD OF DEVELOPING COLD FRONT. EXPECTING A FEW
STRONG STORMS WITH HEAVY RAIN AND MICROBURST POTENTIAL ASSOCIATED
WITH POORLY ORGANIZED MULITCELLS SUPPORTED BY ML CAPE AROUND 1000
J/KG AND WEAK DEEP LAYER SHEAR OF < 20 KTS. SOME MOISTURE POOLING
ALONG FRONTAL BOUNDARY WITH WEAK MOIST FLUX CONVERGENCE AND MODEST UPPER
DIVERGENCE AHEAD OF DIGGING SHORT WAVE WILL PROVIDE FORCING. THAT SHORTWAVE
IS NOW PUSHING THROUGH SOUTHERN ALBERTA AND N MO AND LOOKS PRETTY
GOOD ON WATER VAPOR IMAGERY.
UPDATE ISSUED AT 604 AM EDT SUN AUG 3 2014
I HAVE UPDATED OUR GRIDS AND ZONE FORECAST TO INCLUDE AREAS OF
DENSE FOG NORTH AND EAST OF US-131 AND I-96 TILL ABOUT 9 AM. THE
RAP MODEL SHOWS THE LOW LEVEL FLOW HAS BEEN OFF LAKE HURON INTO
CENTRAL LOWER MICHIGAN AIMED DIRECTLY INTO THE WHERE DENSE FOG HAS
DEVELOPED. THE RAP MODEL VISIBILITY FORECAST...WHICH IS DOING
GREAT ON THE AREA OF DENSE FOG CURRENTLY (05 AM) SHOWS IT TOTALLY
MIXING OUT BY 9 AM. THAT MAKES SENSE AS THERE IS LITTLE IN THE WAY
OF CLOUDS OVER THE FOG AND IT IS SHALLOW FOG TOO. AFTER COORDINATING
WITH APX ON THE ISSUE WE DECIDED NOT TO ISSUE A DENSE FOG ADVISORY
BUT JUST TO PUT AREAS OF DENSE FOG IN THE GRIDS AND CALL THAT
GOOD.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 330 AM EDT SUN AUG 3 2014
OUR PRIMARY SHORT TERM FORECAST CONCERNS INVOLVE DETERMINING
POTENTIAL FOR CONVECTION MONDAY THROUGH TUESDAY.
A WEAK COLD FRONT WILL BRING SCATTERED SHOWERS AND THUNDERSTORMS
MONDAY INTO MONDAY NIGHT. THE BEST CHANCE FOR STORMS MONDAY WILL BE
NEAR TO MAINLY EAST OF US-131 WHERE THERE WILL BE LESS OF A
STABILIZING INFLUENCE FROM LAKE MI.
SB CAPE VALUES WILL POTENTIALLY REACH AROUND 2000 J/KG OVER OUR
EASTERN FCST AREA AS SUGGESTED BY LATEST 00Z GFS AND ECMWF
GUIDANCE. HOWEVER ML CAPE VALUES MAY ONLY REACH AROUND 750 J/KG
OVER OUR SE FCST AREA ACCORDING TO LATEST SREF GUIDANCE.
SEVERE WEATHER IS NOT ANTICIPATED DUE TO RELATIVELY WEAK FORCING
FROM THE WEAK COLD FRONT... WEAK 0-6 KM BULK SHEAR VALUES OF ONLY
AROUND 15-20 KTS AND LACK OF STRONGER INSTABILITY.
A CONSENSUS OF LATEST SHORT RANGE GUIDANCE SUGGESTS SCATTERED
SHOWERS AND PERHAPS A FEW STORMS WILL LINGER MONDAY NIGHT AND THEN
INTO TUESDAY MAINLY NEAR TO SOUTH OF I-96. HOWEVER WEAKER INSTABILITY
IS ANTICIPATED TUESDAY AND IT WILL BE MORE CONFINED TO THE AREA
NEAR TO SOUTH OF I-96.
A WEAK HIGH PRESSURE RIDGE WILL BRING FAIR AND SEASONABLY WARM WX
TODAY WITH MAX TEMPS REACHING THE LOWER TO MIDDLE 80S... EXCEPT A
LITTLE COOLER RIGHT ALONG THE LAKE MI SHORELINE DUE TO SW FLOW AND
THE LAKE BREEZE OFF OF RELATIVELY COLD LAKE WATERS. CANNOT
COMPLETELY RULE OUT POTENTIAL FOR AN ISOLATED SHOWER NEAR OR EAST OF
US-131 THIS AFTERNOON BUT THERE IS NOT ENOUGH POTENTIAL IN IT TO
WARRANT INCLUSION IN THE FCST.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 335 AM EDT SUN AUG 3 2014
IT WOULD NOT BE OUT OF THE QUESTION THERE COULD BE A LINGERING
SHOWER OR THUNDERSTORMS INTO EARLY WEDNESDAY BEHIND THE COLD FRONT
THE PRIMARY MESSAGE FOR THIS FORECAST TIME PERIOD WEATHERWISE IS
DRY. TEMPERATURES WILL ONCE AGAIN FALL BELOW NORMAL DURING THE MID
WEEK PERIOD. BY THE WEEKEND EXPECT TEMPERATURES TO RISE TO ABOVE
NORMAL LEVELS... BUT STILL I DO NOT SEE HIGHS IN THE 90S... MORE
LIKE MID 80S HIGHS BY SATURDAY.
AS I HAVE BEEN SAYING THE PAST FEW NIGHTS... THE EASTERN TROUGH
FORECAST BY THE ECMWF WILL BE STRONG ENOUGH TO BRING THE POLAR JET
SOUTH OF MICHIGAN ONCE AGAIN BY WEDNESDAY. WE THEN GET SHORTWAVE
RIDGING TO BUILD INTO THE AREA BY SATURDAY. THAT WILL BRING THE
WARMER TEMPERATURES TO THE AREA. UNLIKE THIS LAST DEEP UPPER TROUGH
WHEN THE POLAR JET WAS WELL SOUTH OF MICHIGAN FOR SEVERAL DAYS...
THIS TIME IT WILL BE ONLY FOR A DAY. THAT MEANS THERE WILL NOT BE
ENOUGH COLD AIR ALOFT FOR AFTERNOON CONVECTION. HENCE THE DRY
FORECAST FOR WEDNESDAY AFTERNOON THROUGH SATURDAY.
ONE THING TO WATCH FOR... TUESDAY NIGHT WE HAVE THE JET EXIT REGION
OVER SOUTHWEST MICHIGAN. THAT MAY BE ENOUGH TO SUPPORT SOME
THUNDERSTORM ACTIVITY. HOWEVER AT THIS POINT IT LOOKS LIKE TO MUCH
DRY AIR AT MID LEVELS. EVEN SO I HAVE LOW CHANCE POPS FOR THE
SOUTHERN SECTIONS OF THE CWA TUESDAY NIGHT INTO WEDNESDAY MORNING
JUST I CASE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 139 PM EDT SUN AUG 3 2014
THE FOG THAT WAS PRESENT THIS MORNING HAS DISSIPATED WITH THE
SUNSHINE TODAY ALONG WITH WINDS INCREASING A BIT. WE EXPECT VFR
CONDITIONS TO HOLD THROUGH THE AFTERNOON HOURS RIGHT ON THROUGH
THE EVENING HOURS WITH ONLY SCT CUMULUS DEVELOPMENT EXPECTED TO
TAKE SHAPE INLAND FROM LAKE MICHIGAN. WE EXPECT THAT CONVECTION
WILL REMAIN WEST OF LAKE MICHIGAN IN WI...AND EAST OF OUR
TERMINALS.
WE DO EXPECT FOG TO BECOME POSSIBLE ONCE AGAIN TONIGHT WITH LIGHT
WINDS EXPECTED AT THE SFC AND A SLIGHTLY MOIST AIR MASS IN PLACE.
MVFR CONDITIONS ARE A GOOD BET WITH SOME IFR POSSIBLE. THERE IS A
VERY SLIGHT CHC OF A SHOWER OR STORM LATE IN THE NIGHT...HOWEVER
WE FEEL THAT CONVECTION SHOULD HOLD OFF UNTIL MON AFTERNOON NORTH
AND ALMOST MON EVENING SOUTH AWAY FROM THE LAKE AS A FRONT DROPS
DOWN INTO THE AREA.
&&
.MARINE...
ISSUED AT 1046 AM EDT SUN AUG 3 2014
CONTINUE TO SEE SOME FOG...MAY INCREASE IN COVERAGE AND DENSITY
OVERNIGHT TONIGHT AS AIRMASS MOISTENS FURTHER AHEAD OF NEXT COLD
FRONT. FOG MAY CONTINUE TO BE A THREAT UNTIL TUE AFTERNOON WHEN
DRIER AIR WORKS INTO THE AREA. NO WIND OR WAVE ISSUES IN THE
&&
.HYDROLOGY...
ISSUED AT 306 PM EDT SAT AUG 2 2014
NO HYDRO ISSUES DUE TO A FAIRLY DRY WEATHER PATTERN. BRIEF PERIODS
OF LOCALLY HEAVY RAINFALL ARE POSSIBLE THIS EVENING IN SCATTERED
THUNDERSTORMS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...COBB
SYNOPSIS...LAURENS
SHORT TERM...LAURENS
LONG TERM...WDM
AVIATION...NJJ
HYDROLOGY...93
MARINE...COBB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
346 PM CDT SUN AUG 3 2014
.SYNOPSIS...
ISSUED AT 345 PM CDT SUN AUG 3 2014
AT 19Z WATER VAPOR IMAGERY SHOWS THE CONTINUED WESTERN RIDGE/EASTERN
TROUGH PATTERN ONGOING. HOWEVER THERE IS A POTENT UPPER LEVEL LOW
MOVING INTO SOUTHERN CALIFORNIA ON THE WESTERN SIDE OF THE RIDGE.
ACROSS CANADA...COULD SEE A FEW NOTABLE SHORTWAVE TROUGHS...THE
FIRST OVER NORTHERN SASKATCHEWAN AND THE SECOND OVER SOUTHERN
BRITISH COLUMBIA. OTHER WEAK DISTURBANCES COULD ALSO BE SEEN
ROUNDING THE RIDGE AND MOVING THROUGH NORTHWEST FLOW INTO THE
CENTRAL PLAINS AND UPPER MISSISSIPPI RIVER VALLEY. LOCALLY...A WEAK
SURFACE BOUNDARY WAS SEEN FROM NORTHWEST NEBRASKA ARCING DOWN INTO
SOUTH CENTRAL NEBRASKA...ROUGHLY FROM KCDR TO KLBF TO KGRI.
TEMPERATURES HAD REACHED THE UPPER 80S AND LOW 90S MOST
PLACES...WHICH WERE AT OR NEAR FULL MIXING POTENTIAL. STARTING TO
SEE SOME CUMULUS POP UP ACROSS THE AREA...WHILE AREAL COVERAGE IS
LOW DUE TO A LACK OF MID LEVEL MOISTURE.
&&
.SHORT TERM...(TONIGHT THROUGH MONDAY)
ISSUED AT 345 PM CDT SUN AUG 3 2014
ANY SHOWERS OR STORMS THAT DEVELOP ACROSS THE FORECAST AREA THIS
AFTERNOON DUE TO THE FAVORABLE LOW AND MID LEVEL CONDITIONS FOR GOOD
SB INSTABILITY WITH THE STEEP LOW AND MID LEVEL LAPSE RATES SHOULD
BE FAIRLY SHORT LIVED AND EXPECT ANY ACTIVITY TO END EARLY THIS
EVENING WITH THE LOSS OF DAYTIME HEATING AND STABILIZATION OF THE
BOUNDARY LAYER AS THERE WILL NOT BE SUPPORT ALOFT TO SUSTAIN ANY OF
THIS ACTIVITY.
ALTHOUGH IT IS DIFFICULT TO PICK OUT IN WATER VAPOR IMAGERY...MODELS
INDICATE A WEAK SHORTWAVE TROUGH OVER SOUTHERN MONTANA
CURRENTLY...WITH ANOTHER WEAK DISTURBANCE OVER WESTERN SOUTH DAKOTA.
THE SD SHORTWAVE MAY BRING ENOUGH LIFT TO BRING SOME SCATTERED
SHOWERS AND THUNDERSTORMS INTO NORTHWEST NEBRASKA THIS EVENING.
CONFIDENCE IS NOT HIGH IN THIS OCCURRING AS MOISTURE IS FAIRLY
LIMITED...BUT THE HRRR AND RAP HAVE BEEN CONSISTENTLY SIGNALING SOME
STRONGER CONVERGENCE AND LIFT IN THIS AREA SO WILL INCLUDE A SLIGHT
CHANCE IN THIS EVENING OVER THE NORTHWEST CORNER OF THE FORECAST
AREA. THEN OVERNIGHT...THE SHORTWAVE TROUGH OVER MONTANA WILL MAKE
ITS WAY INTO NORTH CENTRAL NEBRASKA. AS HAS BEEN OCCURRING FOR
SEVERAL DAYS...TEMPERATURES ARE COOL ENOUGH IN THE MID LEVELS TO
KEEP LAPSE RATES VERY STEEP AND EVEN SLIGHT LIFT FROM WEAK
SHORTWAVES SEEMS TO BE ENOUGH TO ALLOW STORMS TO DEVELOP
NOCTURNALLY. ALTHOUGH THERE IS QUESTION TO IF THERE WILL BE ENOUGH
MOISTURE TO WORK WITH...AND EXACTLY WHERE THE CHANCES WILL BE BEST
THE CURRENT THOUGHTS ARE THAT ACTIVITY WILL PASS ACROSS THE
NORTHEAST PART OF THE FORECAST AREA...ROUGHLY EAST OF A VALENTINE TO
TAYLOR LINE. THIS ENDS EARLY MONDAY MORNING.
THE UPPER LEVEL PATTERN DOES BEGIN TO SEE A SHIFT THROUGH THE DAY
MONDAY. THE UPPER LOW OVER CALIFORNIA WILL MOVE INTO THE RIDGE WHICH
WILL CAUSE THE RIDGE TO START SHIFTING EAST. MEANWHILE...THE
SHORTWAVE OVER SASKATCHEWAN WILL DIVE INTO THE GREAT LAKES REGION TO
PUSH A COLD FRONT THROUGH THE UPPER MISSISSIPPI RIVER VALLEY AND
APPROACH NORTHEAST NEBRASKA BY THE END OF THE DAY. ALSO...THE
BRITISH COLUMBIA SHORTWAVE WILL START SLOW EASTERLY MOVEMENT WHICH
WILL PLAY THE PART OF FLATTENING THE RIDGE. THIS MOVEMENT IN THE
UPPER LEVELS WILL LEAD TO LOW PRESSURE DEVELOPING OVER THE LEE SIDE
OF THE ROCKIES TONIGHT AND MONDAY...WITH WINDS IN TURN SWITCHING
AROUND TO THE SOUTH BY MONDAY MORNING. EXPECTING THE WINDS TO
INCREASE THROUGH THE DAY AS THE PRESSURE GRADIENT TIGHTENS. AS THE
RIDGE SHIFTS EAST...TEMPERATURES ALOFT WILL WARM ON MONDAY. CURRENT
700MB TEMPERATURES IN THE UPPER SINGLE DIGITS LOOK TO INCREASE TO
11-13C BY 00Z TUESDAY SO SHOULD HAVE THE POTENTIAL FOR A SLIGHTLY
WARMER DAY FOR MOST LOCATIONS FOR MONDAY WITH FORECAST HIGHS FROM
AROUND 90 TO THE MID 90S NORTHEAST TO SOUTHWEST.
MAINTAINED THE SLIGHT CHANCES FOR SHOWERS AND STORMS ACROSS THE
NORTH AND WEST MONDAY AFTERNOON. A SHORTWAVE MOVES TOWARDS NEBRASKA
IN THE AFTERNOON OUT OF WYOMING AND COLORADO...HOWEVER THE TIMING
LOOKS BETTER WITH THIS INTO THE EVENING. THE MODELS DO CONTINUE TO
DEVELOP PRECIPITATION OVER NORTHERN NEBRASKA IN THE AFTERNOON AS
MOISTURE POOLS ALONG A BOUNDARY IN THE VICINITY OF THE NE/SD BORDER.
DEWPOINTS RISE INTO THE UPPER 50S AND 60S AT THE SURFACE AND MID
LEVEL MOISTURE INCREASES...AND WITH LOW LEVEL LAPSE RATES STAYING
STEEP...PRECIPITATION CONTINUES TO LOOK POSSIBLE. INSTABILITY ISN/T
GREAT...WITH MU VALUES BEING UP TO 1000 J/KG...BUT DEEP LAYER SHEAR
WILL BE INCREASING SO COULD GET A FEW CELLS TO ORGANIZE IN THESE
AREAS TO GET A FEW STRONGER STORMS. WIDESPREAD SEVERE WEATHER IS NOT
ANTICIPATED.
&&
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 345 PM CDT SUN AUG 3 2014
A PATTERN SHIFT WILL LEAD TO A SURFACE LOW AND ASSOCIATED FRONTAL
SYSTEM MOVING SOUTHEAST MONDAY THROUGH WEDNESDAY NIGHT. A HIGHER
CHANCE FOR THUNDERSTORMS OCCURS TUESDAY NIGHT AS SEVERAL
DISTURBANCES MOVE EAST. THE PRECIPITABLE WATER RATIOS WILL BE
HIGHER WHERE HEAVY RAIN IS POSSIBLE WITH THUNDERSTORMS THAT MAY
FORM. AS THE FRONT MOVES EAST AND SOUTH THURSDAY THE TRAILING END
OF THE FRONT BACKS WEST AND NORTHWEST THROUGH THE WESTERN
PANHANDLE. IF THE FRONT STALLS ACROSS NORTHERN KANSAS AS SHOWN...A
PREVAILING EASTERLY SURFACE FLOW WOULD INCREASE THE MOISTURE
SUPPLY FOR INCREASED CLOUDS INTO THE EXTENDED PERIOD. A CHANCE OF
THUNDERSTORMS DAILY LINGERS AS THE STALLED BOUNDARY TO THE SOUTH
WOULD KEEP TEMPERATURES CLOSER TO NORMAL...OR BELOW NORMAL
...GOING FORWARD WITH DAYTIME HIGHS IN THE 80S OVER THE
SOUTHWEST...AND 70S IN THE NORTH AND NORTH CENTRAL. MODEL
CONSENSUS DIVERGES BEYOND WEDNESDAY NIGHT WITH A SUPERBLEND OF THE
SOLUTIONS USED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 125 PM CDT SUN AUG 3 2014
HAVE INCLUDED VICINITY THUNDER IN THE FORECAST FOR KLBF LATER THIS
AFTERNOON AS ISOLATD SHOWERS AND THUNDERSTORMS COULD DEVELOP IN THE
AREA ALONG A WEAK SURFACE BOUNDARY. THINK COVERAGE WILL BE VERY
ISOLATED AND LITTLE CONFIDENCE ON IMPACTS TO THE TERMINAL SO NO
PREVAILING MENTION AT THIS TIME. LATER TONIGHT THUNDERSTORMS ARE
POSSIBLE UP OVER NORTH CENTRAL NEBRASKA. HAVE HIGHER CONFIDENCE IN
STORMS TO THE EAST OF THE KVTN TERMINAL SO WILL KEEP PREVAILING
THUNDERSTORMS OUT OF THE FORECAST AT THIS TIME. OTHERWISE...LOOK
FOR A SLOW SHIFT IN THE WINDS TO THE SOUTH BY LATE MORNING ON
MONDAY. WILL LIKELY SEE WIND SPEEDS INCREASE INTO MONDAY AFTERNOON.
&&
.HYDROLOGY...
ISSUED AT 345 PM CDT SUN AUG 3 2014
ON THE NORTH PLATTE RIVER...FROM LAKE MCCONAUGHY DOWNSTREAM TO
BRADY...IRRIGATION RELEASES CONTINUE TO SLOWLY CREEP UP THE FLOWS WITH
THE CURRENT STAGE AT THE NORTH PLATTE GAGE AT 5.4 FEET. THE RIVER
FORECAST FOR THE NORTH PLATTE GAGE...NEAR THE HIGHWAY 83 BRIDGE...IS
FOR FLOWS TO REMAIN AROUND 5.5 FEET THROUGH THURSDAY. THERE IS A
CHANCE FOR THUNDERSTORMS DAILY WHERE SOME FLUCTUATIONS ARE
POSSIBLE.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...BROOKS
SHORT TERM...BROOKS
LONG TERM...KECK
AVIATION...BROOKS
HYDROLOGY...KECK
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
125 PM CDT SUN AUG 3 2014
.SYNOPSIS...
ISSUED AT 326 AM CDT SUN AUG 3 2014
STARTING TO SEE SOME CHANGES IN THE UPPER LEVELS. THE MAIN WESTERN
RIDGE AND EASTERN TROUGH CONTINUE...HOWEVER A CLOSED LOW ACROSS SRN
CAL IS SHOWING SIGNS OF MOVING NORTH WHICH WILL EVENTUALLY FLATTEN
THE RIDGE. THIS MOVEMENT OF THE LOW HAS NOT CHANGED ANYTHING FOR THE
HIGH PLAINS YET...THUS THE EFFECTIVE WEATHER REMAINS SIMILAR TO THE
PAST SEVERAL DAYS. NORTHWEST FLOW WITH NUMEROUS DISTURBANCES
DRIFTING ACROSS THE AREA. THIS MORNING A COUPLE OF DISTURBANCES HAVE
PUSHES SOUTH AND EAST OF THE CWA...WITH MORE OVER THE NORTHERN
ROCKIES. CLEAR TO MOSTLY CLEAR SKIES HAVE ALLOWED FOR TEMPS TO COOL
WITH SOME PATCHY FOG STARTING TO BE REPORTED IN THE EASTERN
ZONES...WHERE HIGHEST DEW PTS ARE LOCATED.
&&
.UPDATE...
ISSUED AT 125 PM CDT SUN AUG 3 2014
CONTINUING TO WATCH POTENTIAL FOR THUNDERSTORMS THIS
AFTERNOON. CURRENT LAPS SOUNDINGS SHOW A LACK OF MOISTURE IN THE
MID LEVELS SO THERE IS CONCERN THAT EVEN WHEN REACHING PEAK
HEATING AND FULL MIXING IN THE NEXT FEW HOURS THAT THERE WON/T BE
ENOUGH MOISTURE TO ALLOW ANY DEVELOPMENT. THE LATEST RUNS OF THE
RAP AND NAM INDICATE AN INCREASE IN 700-600MB MOISTURE THIS
AFTERNOON AND THE 03.16Z HRRR CONTINUES TO DEVELOP SOME ISOLATED
ACTIVITY IN THE VICINITY OF A WEAK SURFACE BOUNDARY FROM THE
WESTERN SANDHILLS DOWN THROUGH SOUTH CENTRAL NEBRASKA.
SO...DESPITE LOW CONFIDENCE WILL CONTINUE THE MENTION OF ISOLATED
SHOWERS AND THUNDERSTORMS THIS AFTERNOON.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 326 AM CDT SUN AUG 3 2014
SOME PATCHY MORNING FOG WILL QUICKLY BURN OFF WITH MOSTLY SUNNY
SKIES THIS MORNING. BY AFTERNOON TEMPS WILL WARM TO AROUND 90 WITH
SOME LOWER TO MID 90S POSSIBLE. THIS WILL CREATE ENOUGH INSTABILITY
FOR ANOTHER ROUND OF ISOLATED TO SCATTERED THUNDERSTORMS. A
DISTURBANCE ACROSS EASTERN MONTANA/NORTHEAST WYOMING...SHOULD BE
MOVING OVERHEAD AND ADD TO THE LIFT. SHEAR CONTINUES TO BE
MARGINAL...AS IS CAPE...HOWEVER SEEING WHAT HAS OCCURRED THE PAST
SEVERAL DAYS...A FEW STRONG STORMS ARE POSSIBLE. CANNOT TOTALLY RULE
OUT A STRAY SEVERE STORM OR TWO.
ONCE WE BEGIN TO COOL THIS EVENING...THE SHOWER ACTIVITY SHOULD
BEGIN TO DIMINISH. SKIES SHOULD SEE DECREASING CLOUDS WITH TEMPS TO
FALL INTO THE LOWER 60S...LOCALLY AN UPPER 50 READING POSSIBLE IN
THE WEST BY MORNING.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 326 AM CDT SUN AUG 3 2014
A WARM START TO THE WORK WEEK WILL BE FOLLOWED BY A COOL DOWN WITH
INCREASING CHANCES FOR RAIN BY MID INTO LATE WEEK.
SURFACE HIGH PRESSURE WILL NOSE INTO THE GREAT LAKES FROM CANADA
MONDAY AND TUESDAY. THIS WILL PUSH A COLD FRONT SOUTHWEST INTO THE
AREA. MODELS AGREE THAT THE FRONT WILL BECOME STATIONARY FROM
ROUGHLY THE NORTHERN NEBRASKA PANHANDLE...SOUTHEASTWARD THROUGH
CENTRAL AND INTO EASTERN NEBRASKA. TO THE SOUTH OF THE BOUNDARY
ACROSS THE SOUTHERN NEBRASKA PANHANDLE INTO SOUTHWEST
NEBRASKA...IT WILL REMAIN WARM WITH HIGHS IN THE 90S. MEANWHILE
EASTERLY WINDS AND POOLING MOISTURE TO THE NORTH OF THE FRONT
ACROSS NORTHERN NEBRASKA WILL KEEP IT COOLER...WITH HIGHS FROM 80
TO 85 DEGREES. WILL CONTINUE THE SLIGHT CHANCE FOR STORMS ACROSS
NORTHERN NEBRASKA MONDAY AFTERNOON NEAR THE FRONT...AND THEN
INCREASE INTO THE CHANCE CATEGORY MONDAY NIGHT AS A SOUTHERLY LOW
LEVEL JET DEVELOPS. A FAIRLY STRONG SHORTWAVE IS STILL ADVERTISED
TO CROSS THE REGION TUESDAY AND TUESDAY NIGHT...WITH THUNDERSTORM
CHANCES LOOKING PRETTY DECENT...ESPECIALLY ACROSS NORTHERN
PORTIONS OF THE STATE. THIS SHORTWAVE WILL FORCE THE STATIONARY
FRONT SOUTH INTO KANSAS WEDNESDAY...BRINGING COOLER HIGHS IN THE
80S INTO SOUTHWEST NEBRASKA AND PERHAPS ONLY UPPER 70S ACROSS THE
NORTH.
THE FRONT WILL REMAIN ACROSS KANSAS INTO LATE WEEK...WITH EAST TO
SOUTHEAST MOIST UPSLOPE FLOW ACROSS CENTRAL AND WESTERN NEBRASKA.
SOME CHANCE FOR CONVECTION EACH DAY...AS STORMS FIRE ON THE HIGHER
TERRAIN TO THE WEST AND ATTEMPT TO MOVE EAST DURING THE
AFTERNOONS AND EVENINGS. HIGHS WILL REMAIN NEAR OR SLIGHTLY BELOW
NORMAL IN THE 80S...LOW TEMPERATURES HOWEVER WILL BE NEAR OR
SLIGHTLY ABOVE NORMAL IN THE 60S DUE TO HIGHER HUMIDITY HELPING TO
KEEP THE NIGHTS WARM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 125 PM CDT SUN AUG 3 2014
HAVE INCLUDED VICINITY THUNDER IN THE FORECAST FOR KLBF LATER THIS
AFTERNOON AS ISOLATD SHOWERS AND THUNDERSTORMS COULD DEVELOP IN THE
AREA ALONG A WEAK SURFACE BOUNDARY. THINK COVERAGE WILL BE VERY
ISOLATED AND LITTLE CONFIDENCE ON IMPACTS TO THE TERMINAL SO NO
PREVAILING MENTION AT THIS TIME. LATER TONIGHT THUNDERSTORMS ARE
POSSIBLE UP OVER NORTH CENTRAL NEBRASKA. HAVE HIGHER CONFIDENCE IN
STORMS TO THE EAST OF THE KVTN TERMINAL SO WILL KEEP PREVAILING
THUNDERSTORMS OUT OF THE FORECAST AT THIS TIME. OTHERWISE...LOOK
FOR A SLOW SHIFT IN THE WINDS TO THE SOUTH BY LATE MORNING ON
MONDAY. WILL LIKELY SEE WIND SPEEDS INCREASE INTO MONDAY AFTERNOON.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BROOKS
SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...TAYLOR
AVIATION...BROOKS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
156 PM EDT SUN AUG 3 2014
.SYNOPSIS...A SLOW MOVING UPPER LEVEL TROUGH OVER THE TENNESSEE
VALLEY COUPLED WITH A STATIONARY SURFACE BOUNDARY STRETCHING SOUTH
TO NORTH OVER COASTAL CAROLINAS WILL MAINTAIN A MOIST AND UNSETTLED
WEATHER PATTERN OVER MOST OF CENTRAL NC THROUGH MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 AM SUNDAY...
UPPER LEVEL TROUGH REMAINS WEST OF THE AREA WITH UPPER LEVEL LOW
PRESSURE CENTERED OVER THE OHIO VALLEY. UPPER AIR ANALYSIS FROM 12Z
SHOWS SHEAR AXIS ASSOCIATED WITH SHORTWAVE EXTENDING DOWN THROUGH
TENNESSEE. THIS WAVE WILL MOVE INTO THE NW PIEDMONT LATER TODAY AND
HOPEFULLY WILL ACT AS AN ERODING MECHANISM TO BEGIN BREAKING UP THE
CAD WEDGE...AT LEAST THE TRIAD. TIMING OF THIS FEATURE WILL BE TOUGH
BUT THE RAP HAS IT MAKING HEADWAY INTO THE TRIAD BY EARLY AFTERNOON
WITH A SUBSEQUENT DROP IN DEWPOINTS AND RELATIVE HUMIDITY. THEREFORE
EXPECTING A SIMILAR DEPICTION OF THE PRECIP TO WHAT THE RADAR IS
SHOWING NOW WHICH IS A VERY DEFINITIVE LINE OF PRECIP IN THE COASTAL
PLAIN WITH MUCH DRIER CONDITIONS WEST OF I-95. THAT BEING SAID...THE
TRIANGLE AREA WILL PROBABLY STAY CLOUDY FOR MUCH OF THE DAY WITH
ONLY THE NW PIEDMONT HAVING A REAL CHANCE OF BREAKING OUT THIS
AFTERNOON. THIS WILL MAKE TEMPERATURES TRICKY WITH AN ABNORMAL
DISTRIBUTION OF WARMEST TEMPERATURES IN THE NW AND COOLEST IN THE
SOUTHEAST. IF THE CAD BREAKS DOWN...COULD EASILY SEE LOWER 80S IN
THE TRIAD WITH POSSIBLY ONLY MID 70S IN THE SOUTHEAST. THE GREATEST
THREAT FOR PRECIPITATION WILL BE IN THE EXTREME SOUTHEAST TODAY WITH
SAMPSON COUNTY BEING MONITORED AT THIS TIME FOR POTENTIAL URBAN AND
SMALL STREAM FLOODING. KLTX RADAR INDICATES BETWEEN 2 AND 3 INCHES
OF RAIN FALLEN IN THIS LOCATION ALREADY WITH SOME FURTHER TRAINING
OF MODERATE TO HEAVY RAIN POSSIBLE OVER THE NEXT FEW HOURS. THE
FLOOD WATCH REMAINS IN EFFECT THROUGH 00Z MONDAY FOR THE EASTERN
TIER OF COUNTIES. NOT EXPECTING MUCH IN THE WAY OF SEVERE WEATHER
THIS AFTERNOON ALTHOUGH THERE WILL BE SOME DECENT INSTABILITY IN THE
EAST...SHEAR VALUES HAVE DROPPED OFF SIGNIFICANTLY BUT ARE STILL AT
A MODEST 25 KTS. AS IN PREVIOUS DAYS...THE EXTENSIVE OVERCAST AND
LACK OF INSOLATION SHOULD INHIBIT MOST THUNDERSTORM ACTIVITY THIS
AFTERNOON.
IF SOME CLEARING DOES OCCUR IN THE TRIAD...CAN EXPECT ANOTHER ROUND
OF POTENTIALLY DENSE FOG OVERNIGHT. ELSEWHERE A PERSISTENCE FORECAST
OF LIFR/IFR CEILINGS WILL PROBABLY WORK OUT WELL. THERE SHOULD BE A
LULL IN PRECIPIATION AS PRECIPITATION BEGINS TO PUSH EASTWARD
OFFSHORE. LOW TEMPERATURES TONIGHT MID 60S NW TO NEAR 70 SE.
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
AS OF 420 AM SUNDAY...
STILL A DECENT THREAT FOR ADDITIONAL SHOWERS AND STORMS OVER OUR
EASTERN PERIPHERY AS MID-UPPER LEVEL SHEAR AXIS WITHIN THE MOISTURE
PLUME ONLY DRIFTS SLOWLY EWD. PLAN TO HAVE LIKELY POPS OVER THE
COASTAL PLAIN AND SANDHILLS...TAPERING TO A SMALL CHANCE IN THE
WESTERN PIEDMONT. AFTER MORNING LOW CLOUDS AND FOG BURN-OFF...EXPECT
PARTIAL SUNSHINE ACROSS THE PIEDMONT. THIS SHOULD WARM TEMPS INTO
THE LOW-MID 80S. A SURFACE WAVE LIFTING NEWD JUST OFFSHORE WILL
MAINTAIN A THREAT FOR SHOWERS ACROSS THE COASTAL PLAIN THROUGH THE
OVERNIGHT HOURS. AGAIN...SHOULD SEE AREAS OF LOW CLOUDS AND/OR FOG
DEVELOP. MIN TEMPS MID 60S TO AROUND 70.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 320 AM SUNDAY...
TUESDAY THROUGH WEDNESDAY NIGHT: HIGHER PW`S ARE EXPECTED TO PUSH TO
THE EAST OF THE AREA DURING THE PERIOD AS WE CONTINUE TO TRANSITION
TO MORE OF A TYPICAL SUMMERTIME PATTERN. MID LEVEL TROUGHING ACROSS
THE EASTERN U.S. WILL REMAIN THOUGH... WITH A LEE SIDE TROUGH
DEVELOPING/BECOMES MORE ESTABLISHED OVER THE AREA. THIS WILL LEAD TO
MORE OF A SLIGHT CHANCE/LOW END CHANCE OF SHOWERS AND STORMS FOR
TUESDAY... WITH EVEN A LESSER CHANCE ON WEDNESDAY (BEST CHANCE
ACROSS THE EAST). GIVEN THE DRIER MID LEVEL AIR EXPECTED TO MOVE
INTO THE AREA DURING THIS TIME... EXPECT WE SHOULD SEE MORE INCOMING
SOLAR RADIATION... RESULTING IN WARMING TEMPS BOTH DAYS AS AFTERNOON
LOW LEVEL THICKNESS VALUES AREA EXPECTED TO CLIMB INTO 1415-1430
METER RANGE... HIGHEST WEDNESDAY IN ADVANCE OF ANOTHER FRONT. THIS
WILL YIELD A CONTINUED WARMING TREND... WITH HIGHS AT LEAST IN THE
UPPER 80S TO LOWER 90S ON TUESDAY... WITH HIGHS A FEW DEGREES WARMER
ON WEDNESDAY (WITH POSSIBLY SOME MID 90S SOUTH). LOWS ARE EXPECTED
TO BE IN THE MID TO UPPER 60S... WITH SOME LOWER 70S SOUTH/SOUTHEAST.
THURSDAY THROUGH SATURDAY: A NORTHERN STREAM TROUGH IS EXPECTED TO
AMPLIFY THE MID LEVEL TROUGH ACROSS THE EASTERN U.S. AND SEND
ANOTHER COLD FRONT INTO AND POSSIBLY ACROSS CENTRAL NC ON THURSDAY.
THIS SHOULD LEAD TO A BETTER CHANCE OF SHOWERS AND STORMS ON
THURSDAY. HOWEVER... THIS WILL DEPEND ON THE ACTUAL TIMING OF THE
FRONT. FOR NOW WILL TREND CLOSER TO WPC... WHICH IS SIMILAR TO THE
LATEST ECMWF ALLOWING THE FRONT TO BECOME MORE ACTIVE AS IT MOVES
INTO THE AREA DURING PEAK HEATING ON THURSDAY. THE SURFACE FRONT IS
EXPECTED TO STALL NEAR THE NC/SC BORDER... LEADING TO CONTINUED
CHANCES OF SHOWERS AND STORMS... ESPECIALLY ACROSS THE SOUTHERN HALF
OF THE AREA. EXPECT HIGHS WILL BE COOLER BEHIND THE FRONT. FOR NOW
WILL STICK CLOSE TO WPC... HIGHS IN THE 80S... LOWS IN THE 60S.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
AS OF 200 PM SUNDAY...
24 HOUR TAF PERIOD: SOME SIGNS OF IMPROVING CONDITIONS OUT THERE
THIS AFTERNOON WITH MOST SIGHTS COMING IN WITH MVFR CEILINGS BUT THE
TRIAD IS STARTING TO SCATTER OUT A BIT AND THAT TREND SHOULD
CONTINUE THROUGH THE AFTERNOON. THEREFORE EXPECTING MOSTLY VFR
CONDITIONS IN THE TRIAD WITH MVFR CONDITIONS TO THE EAST BUT EVEN
THE EAST WILL HAVE A CHANCE TO BREAK OUT AS THE AFTERNOON GOES
ON...IF ONLY BRIEFLY. WITH A MOIST AIRMASS STILL IN PLACE AND SOME
POTENTIAL CLEARING...DENSE FOG IS A POSSIBILITY AGAIN
OVERNIGHT...ESPECIALLY IN THE TRIAD WITH AREAS OF FOG ELSEWHERE AND
LIFR CEILINGS AGAIN POSSIBLE OVER MUCH OF THE AREA. THIS WILL OCCUR
AFTER 6Z IN THE EAST AND MAY HOLD OFF TO NEAR 9Z IN THE WEST. WINDS
WILL BE LIGHT AND VARIABLE THROUGH THE TAF PERIOD AND FOR THE MOST
PART PRECIPIATION SHOULD STAY EAST OF THE FORECAST AREA...SO HAVE
TAKEN IT OUT OF THE TAFS AT THIS TIME BUT IT WILL BE A POSSIBILITY
AGAIN TOMORROW ESPECIALLY IN THE EAST.
LONG TERM: A LOW WILL TRACK OFF THE COAST ON MONDAY BUT THE UPPER
LEVEL TROUGH WILL BEGIN TO FINALLY LIFT OUT...LEADING TO A GENERAL
IMPROVEMENT IN CONDITIONS THROUGH THE FIRST HALF OF THE WEEK BEFORE
A SYSTEM MOVES IN FROM THE NORTHWEST FOR THE END OF THE WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...ELLIS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
132 PM EDT SUN AUG 3 2014
.SYNOPSIS...A SLOW MOVING UPPER LEVEL TROUGH OVER THE TENNESSEE
VALLEY COUPLED WITH A STATIONARY SURFACE BOUNDARY STRETCHING SOUTH
TO NORTH OVER COASTAL CAROLINAS WILL MAINTAIN A MOIST AND UNSETTLED
WEATHER PATTERN OVER MOST OF CENTRAL NC THROUGH MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 AM SUNDAY...
UPPER LEVEL TROUGH REMAINS WEST OF THE AREA WITH UPPER LEVEL LOW
PRESSURE CENTERED OVER THE OHIO VALLEY. UPPER AIR ANALYSIS FROM 12Z
SHOWS SHEAR AXIS ASSOCIATED WITH SHORTWAVE EXTENDING DOWN THROUGH
TENNESSEE. THIS WAVE WILL MOVE INTO THE NW PIEDMONT LATER TODAY AND
HOPEFULLY WILL ACT AS AN ERODING MECHANISM TO BEGIN BREAKING UP THE
CAD WEDGE...AT LEAST THE TRIAD. TIMING OF THIS FEATURE WILL BE TOUGH
BUT THE RAP HAS IT MAKING HEADWAY INTO THE TRIAD BY EARLY AFTERNOON
WITH A SUBSEQUENT DROP IN DEWPOINTS AND RELATIVE HUMIDITY. THEREFORE
EXPECTING A SIMILAR DEPICTION OF THE PRECIP TO WHAT THE RADAR IS
SHOWING NOW WHICH IS A VERY DEFINITIVE LINE OF PRECIP IN THE COASTAL
PLAIN WITH MUCH DRIER CONDITIONS WEST OF I-95. THAT BEING SAID...THE
TRIANGLE AREA WILL PROBABLY STAY CLOUDY FOR MUCH OF THE DAY WITH
ONLY THE NW PIEDMONT HAVING A REAL CHANCE OF BREAKING OUT THIS
AFTERNOON. THIS WILL MAKE TEMPERATURES TRICKY WITH AN ABNORMAL
DISTRIBUTION OF WARMEST TEMPERATURES IN THE NW AND COOLEST IN THE
SOUTHEAST. IF THE CAD BREAKS DOWN...COULD EASILY SEE LOWER 80S IN
THE TRIAD WITH POSSIBLY ONLY MID 70S IN THE SOUTHEAST. THE GREATEST
THREAT FOR PRECIPITATION WILL BE IN THE EXTREME SOUTHEAST TODAY WITH
SAMPSON COUNTY BEING MONITORED AT THIS TIME FOR POTENTIAL URBAN AND
SMALL STREAM FLOODING. KLTX RADAR INDICATES BETWEEN 2 AND 3 INCHES
OF RAIN FALLEN IN THIS LOCATION ALREADY WITH SOME FURTHER TRAINING
OF MODERATE TO HEAVY RAIN POSSIBLE OVER THE NEXT FEW HOURS. THE
FLOOD WATCH REMAINS IN EFFECT THROUGH 00Z MONDAY FOR THE EASTERN
TIER OF COUNTIES. NOT EXPECTING MUCH IN THE WAY OF SEVERE WEATHER
THIS AFTERNOON ALTHOUGH THERE WILL BE SOME DECENT INSTABILITY IN THE
EAST...SHEAR VALUES HAVE DROPPED OFF SIGNIFICANTLY BUT ARE STILL AT
A MODEST 25 KTS. AS IN PREVIOUS DAYS...THE EXTENSIVE OVERCAST AND
LACK OF INSOLATION SHOULD INHIBIT MOST THUNDERSTORM ACTIVITY THIS
AFTERNOON.
IF SOME CLEARING DOES OCCUR IN THE TRIAD...CAN EXPECT ANOTHER ROUND
OF POTENTIALLY DENSE FOG OVERNIGHT. ELSEWHERE A PERSISTENCE FORECAST
OF LIFR/IFR CEILINGS WILL PROBABLY WORK OUT WELL. THERE SHOULD BE A
LULL IN PRECIPIATION AS PRECIPITATION BEGINS TO PUSH EASTWARD
OFFSHORE. LOW TEMPERATURES TONIGHT MID 60S NW TO NEAR 70 SE.
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
AS OF 420 AM SUNDAY...
STILL A DECENT THREAT FOR ADDITIONAL SHOWERS AND STORMS OVER OUR
EASTERN PERIPHERY AS MID-UPPER LEVEL SHEAR AXIS WITHIN THE MOISTURE
PLUME ONLY DRIFTS SLOWLY EWD. PLAN TO HAVE LIKELY POPS OVER THE
COASTAL PLAIN AND SANDHILLS...TAPERING TO A SMALL CHANCE IN THE
WESTERN PIEDMONT. AFTER MORNING LOW CLOUDS AND FOG BURN-OFF...EXPECT
PARTIAL SUNSHINE ACROSS THE PIEDMONT. THIS SHOULD WARM TEMPS INTO
THE LOW-MID 80S. A SURFACE WAVE LIFTING NEWD JUST OFFSHORE WILL
MAINTAIN A THREAT FOR SHOWERS ACROSS THE COASTAL PLAIN THROUGH THE
OVERNIGHT HOURS. AGAIN...SHOULD SEE AREAS OF LOW CLOUDS AND/OR FOG
DEVELOP. MIN TEMPS MID 60S TO AROUND 70.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 320 AM SUNDAY...
TUESDAY THROUGH WEDNESDAY NIGHT: HIGHER PW`S ARE EXPECTED TO PUSH TO
THE EAST OF THE AREA DURING THE PERIOD AS WE CONTINUE TO TRANSITION
TO MORE OF A TYPICAL SUMMERTIME PATTERN. MID LEVEL TROUGHING ACROSS
THE EASTERN U.S. WILL REMAIN THOUGH... WITH A LEE SIDE TROUGH
DEVELOPING/BECOMES MORE ESTABLISHED OVER THE AREA. THIS WILL LEAD TO
MORE OF A SLIGHT CHANCE/LOW END CHANCE OF SHOWERS AND STORMS FOR
TUESDAY... WITH EVEN A LESSER CHANCE ON WEDNESDAY (BEST CHANCE
ACROSS THE EAST). GIVEN THE DRIER MID LEVEL AIR EXPECTED TO MOVE
INTO THE AREA DURING THIS TIME... EXPECT WE SHOULD SEE MORE INCOMING
SOLAR RADIATION... RESULTING IN WARMING TEMPS BOTH DAYS AS AFTERNOON
LOW LEVEL THICKNESS VALUES AREA EXPECTED TO CLIMB INTO 1415-1430
METER RANGE... HIGHEST WEDNESDAY IN ADVANCE OF ANOTHER FRONT. THIS
WILL YIELD A CONTINUED WARMING TREND... WITH HIGHS AT LEAST IN THE
UPPER 80S TO LOWER 90S ON TUESDAY... WITH HIGHS A FEW DEGREES WARMER
ON WEDNESDAY (WITH POSSIBLY SOME MID 90S SOUTH). LOWS ARE EXPECTED
TO BE IN THE MID TO UPPER 60S... WITH SOME LOWER 70S SOUTH/SOUTHEAST.
THURSDAY THROUGH SATURDAY: A NORTHERN STREAM TROUGH IS EXPECTED TO
AMPLIFY THE MID LEVEL TROUGH ACROSS THE EASTERN U.S. AND SEND
ANOTHER COLD FRONT INTO AND POSSIBLY ACROSS CENTRAL NC ON THURSDAY.
THIS SHOULD LEAD TO A BETTER CHANCE OF SHOWERS AND STORMS ON
THURSDAY. HOWEVER... THIS WILL DEPEND ON THE ACTUAL TIMING OF THE
FRONT. FOR NOW WILL TREND CLOSER TO WPC... WHICH IS SIMILAR TO THE
LATEST ECMWF ALLOWING THE FRONT TO BECOME MORE ACTIVE AS IT MOVES
INTO THE AREA DURING PEAK HEATING ON THURSDAY. THE SURFACE FRONT IS
EXPECTED TO STALL NEAR THE NC/SC BORDER... LEADING TO CONTINUED
CHANCES OF SHOWERS AND STORMS... ESPECIALLY ACROSS THE SOUTHERN HALF
OF THE AREA. EXPECT HIGHS WILL BE COOLER BEHIND THE FRONT. FOR NOW
WILL STICK CLOSE TO WPC... HIGHS IN THE 80S... LOWS IN THE 60S.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 740 AM SUNDAY...
ADVERSE AVIATION WEATHER CONDITIONS WILL PERSIST ACROSS MUCH OF
CENTRAL NC THROUGH MONDAY AS THE LOW LEVEL AIR MASS WILL REMAIN VERY
MOIST AND A SERIES OF UPPER LEVEL DISTURBANCES TRIGGER SCATTERED
SHOWERS AND STORMS. THE GREATEST RISK FOR SHOWERS AND POSSIBLY A
THUNDERSTORM WILL BE IN VICINITY OF KFAY AND KRWI. THE RISK FOR
SHOWERS WILL DIMINISH APPRECIABLY AS YOU GO FARTHER WEST INTO THE
PIEDMONT AND FOOTHILLS. WIDESPREAD IFR/LIFR CEILINGS WILL PERSIST
OVERNIGHT INTO THE FIRST HALF OF THIS MORNING WITH AREAS OF DENSE
FOG...MAINLY ACROSS THE WESTERN AND SOUTHERN PIEDMONT.
A SLOW IMPROVEMENT IN AVIATION CONDITIONS SHOULD OCCUR LATER TODAY
IN THE WESTERN PIEDMONT AS DRIER AIR ALOFT MIXES TOWARD THE
SURFACE...AIDING TO DIMINISH LOW LEVEL CLOUDINESS. THERE IS A GOOD
CHANCE THAT VFR CONDITIONS WILL RETURN TO KINT AND KGSO BY EARLY
AFTERNOON. ELSEWHERE...SUB VFR CONDITIONS WILL PERSIST.
ANOTHER ROUND OF MVFR/IFR CEILINGS AND IFR/LIFR FOG APPEARS LIKELY
TONIGHT INTO EARLY MONDAY. EXPECT TO SEE CONDITIONS IMPROVE TO VFR
AT KRDU...KGSO AND KINT BY LATE MORNING-EARLY AFTERNOON MONDAY WHILE
MOSTLY MVFR CONDITIONS LINGER AT KFAY AND KRWI WHERE A RISK OF
SHOWERS AND POSSIBLY A THUNDERSTORM WILL REMAIN.
A SLOW IMPROVEMENT IN AVIATION CONDITIONS ANTICIPATED TUESDAY
THROUGH THURSDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...ELLIS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1255 PM CDT SUN AUG 3 2014
.UPDATE...
ISSUED AT 1255 PM CDT SUN AUG 3 2014
AN UPPER LEVEL SHORTWAVE CONTINUES TO GENERATE ELEVATED SHOWER AND
THUNDERSTORM ACTIVITY OVER PORTIONS OF WESTERN NORTH
DAKOTA...MAINLY SOUTH OF THE MISSOURI RIVER. THE LATEST HRRR PROGS
THESE STORMS TO CONTINUE TO MOVE EAST ACROSS SOUTH CENTRAL NORTH
DAKOTA THIS AFTERNOON. THESE STORMS SHOULD CONTINUE TO REMAIN
BELOW SEVERE LIMITS GIVEN THE ELEVATED NATURE OF THIS CONVECTION.
UPDATED THE FORECAST TO INCREASE POPS FOR THE AFFECTED AREAS THIS
AFTERNOON. NUMEROUS SHOWERS WILL CONTINUE TO MOVE EAST ACROSS
CENTRAL NORTH DAKOTA THIS AFTERNOON...WITH SCATTERED EMBEDDED
THUNDERSTORMS EXPECTED.
UPDATE ISSUED AT 941 AM CDT SUN AUG 3 2014
SCATTERED TO NUMEROUS SHOWERS WITH EMBEDDED THUNDERSTORMS WILL
CONTINUE TO MOVE EAST ACROSS WESTERN NORTH DAKOTA THIS MORNING.
THIS ACTIVITY IS ASSOCIATED WITH AN UPPER LEVEL SHORTWAVE
OVERTOPPING A RIDGE AXIS OVER EASTERN MONTANA.
THE LATEST HRRR PROGS THIS ACTIVITY TO CONTINUE TO MOVE EAST OVER
CENTRAL NORTH DAKOTA THROUGH THE AFTERNOON. THE INCREASED CLOUD
COVER MAY INHIBIT DIABATIC FORCING FROM AFTERNOON HEATING. THIS
WILL LIKELY KEEP AFTERNOON THUNDERSTORMS ELEVATED FOR THE MOST
PART...KEEPING THE STRONG TO SEVERE POSSIBILITIES LOW. FOR NOW
WILL KEEP THE ONGOING CONVECTIVE FORECAST AS IS...AND WILL
CONTINUE TO MONITOR CONVECTIVE TRENDS THROUGH THE AFTERNOON.
OTHERWISE...ONLY REMOVED MORNING FOG FROM THE ONGOING FORECAST.
THE REMAINING FORECAST ELEMENTS ARE ON TRACK. THE UPDATED PRODUCTS
HAVE BEEN SENT.
UPDATE ISSUED AT 648 AM CDT SUN AUG 3 2014
FOLLOWING THE 08 AND 09 UTC HRRR AND 06 UTC NAM...THE CURRENT
CONVECTION ACROSS NORTHEAST MONTANA IS FORECAST TO PROPAGATE
SOUTHEAST ALONG THE LOW LEVEL INSTABILITY AXIS INTO SOUTH CENTRAL
NORTH DAKOTA BY 19-20 UTC. GIVEN CURRENT CLOUD COVER SPREADING
AHEAD OF THE CONVECTION...SURFACE DESTABILIZATION AND OVERALL
INTENSIFICATION OF THIS CONVECTION INTO THE AFTERNOON WILL BE
LIMITED. THEREAFTER...THE GENERAL CONSENSUS OF 00 UTC HIGH
RESOLUTION AND GLOBAL GUIDANCE IS FOR A SECOND CONVECTIVE COMPLEX
TO INITIATE ACROSS EASTERN MONTANA INTO SOUTHERN SASKATCHEWAN LATE
THIS AFTERNOON/EVENING AND PROPAGATE AGAIN SOUTHEAST ALONG THE
INSTABILITY AXIS INTO WESTERN AND CENTRAL NORTH DAKOTA TONIGHT.
GIVEN A LIKELY ARRIVAL NEARING TO AFTER SUNSET...THE SEVERE THREAT
WILL BE MARGINAL WITH THIS SECOND ROUND.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 341 AM CDT SUN AUG 3 2014
THE MAIN CONCERN IN THE SHORT TERM IS THUNDERSTORM CHANCES...AND THE
POSSIBILITY THAT SEVERE STORMS ARE POSSIBLE TODAY AND TONIGHT.
CURRENTLY...SURFACE HIGH PRESSURE WAS OVER MANITOBA WITH LOW
PRESSURE ALONG THE FRONT RANGE OF THE ROCKIES. THE UPPER LEVEL RIDGE
OVER THE ROCKIES AND THE TROUGH OVER HUDSON BAY WAS KEEPING THE
NORTHWEST FLOW ALOFT OVER NORTH DAKOTA. AN EMBEDDED SHORTWAVE MOVING
ACROSS MONTANA WAS ASSOCIATED WITH A CONVECTIVE LINE OF SHOWERS THAT
WAS APPROACHING THE WESTERN BORDER OF NORTH DAKOTA.
THE AFOREMENTIONED EASTERN MONTANA SHORTWAVE IS PROGGED TO MOVE
EAST/SOUTHEAST ACROSS NORTH DAKOTA TODAY...FOLLOWED BY ANOTHER GROUP
OF SHORTWAVES TONIGHT. THIS SETUP WILL KEEP SCATTERED THUNDERSTORMS
IN THE FORECAST TODAY AND TONIGHT.
CAPE VALUES LATE THIS MORNING AND AFTERNOON APPROACH OR EXCEED 2000
J/KG OVER WESTERN NORTH DAKOTA...WITH 0-6 KM BULK SHEAR VALUES OVER
40 KNOTS IN THE SAME AREA. THE STORM PREDICTION CENTER ASSESSMENT
WAS THAT THE SEVERE THREAT WAS MARGINAL AND FOR ISOLATED COVERAGE.
WILL MENTION THIS THREAT IN THE HAZARDOUS WEATHER OUTLOOK...BUT
CONFIDENCE NOT HIGH ENOUGH TO MENTION IN GRAPHICAL FORECAST.
IN THE EARLY MORNING HOURS TODAY...SURFACE DEWPOINT TEMPERATURES
WERE IN THE UPPER 50S AND LOWER 60S. EARLIER FORECAST PACKAGE
MENTIONED THE POSSIBILITY OF PATCHY/AREAS OF FOG...AND WILL KEEP
THIS MENTIONED IN THIS MORNING`S FORECAST PACKAGE AS WELL.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 341 AM CDT SUN AUG 3 2014
RATHER NORMAL SENSIBLE SUMMER WEATHER HIGHLIGHTS THE EXTENDED FORECAST.
THE 00 UTC GUIDANCE SUITE IS IN AGREEMENT ON THE LARGE SCALE
PATTERN OF A BROAD...LOW AMPLITUDE RIDGE ACROSS THE WESTERN AND
CENTRAL CONUS...CONTAINING WITHIN IT MULTIPLE LOW PREDICTABILITY
IMPULSES THROUGH THE EXTENDED FORECAST. ALL FIELDS ARE WITHIN ONE
AND A HALF STANDARD DEVIATIONS OR LESS OF NORMAL...SUGGESTING RATHER
AVERAGE EARLY AUGUST WEATHER WITH DAILY ISOLATED TO SCATTERED
THUNDERSTORMS...GIVEN THE AFOREMENTIONED IMPULSES...AND HIGHS IN
THE UPPER 70S TO MID 80S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1255 PM CDT SUN AUG 3 2014
LIFR CONDITIONS IN THUNDERSTORMS HAVE JUST NOW ENDED OVER KDIK.
THIS CONVECTION WILL CONTINUE TO MOVE EAST ACROSS SOUTH CENTRAL
NORTH DAKOTA THROUGH THE AFTERNOON AND SHOULD IMPACT KBIS BETWEEN
20Z-22Z WITH IFR CONDITIONS...AND COULD BE INTO KJMS BY 23Z.
HOWEVER...THE STORMS SHOULD BE WEAKER BY THE TIME THEY REACH KJMS
AND WILL LIKELY HAVE LESS OF AN IMPACT.
ANOTHER ROUND OF THUNDERSTORMS WILL BE POSSIBLE AFTER MIDNIGHT
TONIGHT MOVING FROM NORTHWEST NORTH DAKOTA INTO SOUTHEASTERN
NORTH DAKOTA THROUGH THE MONDAY MORNING HOURS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TM
SHORT TERM...JV
LONG TERM...AYD
AVIATION...TM
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1244 PM CDT SUN AUG 3 2014
.UPDATE...
ISSUED AT 956 AM CDT SUN AUG 3 2014
HAVE MADE MINOR ADJUSTMENTS TO THE FORECAST. VIS AND WATER VAPOR
IMAGERY SHOWS TWO WAVE MOVES IN THE NORTHERN PLAINS. THE FIRST IS
IN THE RED RIVER VALLEY WITH SOME CONVECTION ASSOCIATED WITH IT. A
STRONGER WAVE WAS JUST MOVING INTO THE WESTERN DAKOTAS. SKIES ARE
CURRENTLY CLEAR ACROSS MOST OF THE AREA...BUT WITH HEATING LATE
THIS MORNING...EXPECT CU TO BEGIN TO DEVELOP FAIRLY
RAPIDLY...FIRST ALONG THE BUFFALO RIDGE AND THEN SPREADING TO MOST
AREAS ALONG AND EAST OF I29. BASED UPON NAM SOUNDINGS...VIRTUALLY
NO CAP WILL EXIST OVER PORTIONS OF SW MN AND NW IA WITH ONLY A
WEAK CAPPING INVERSION AROUND KFSD. THE HRRR DOES SHOW SCATTERED
CONVECTION FORMING DURING THE AFTERNOON IN SW MN AND NW IA. A
STRONGER CAP...AROUND 50 J/KG...EXISTS FARTHER WEST IN THE JAMES
AND MISSOURI VALLEYS AND SHOULD PREVENT ANY CONVECTION TODAY.
THEREFORE EXPECT A FEW THUNDERSTORMS TO DEVELOP DURING THE
AFTERNOON AND PERSIST INTO THE EVENING. BELIEVE CONVECTION WILL
FAVOR THE BUFFALO RIDGE AREA BUT ISOLATED STORMS ARE POSSIBLE
ALMOST ANYWHERE ALONG AND EAST OF 29 AND HAVE INCLUDED SIOUX FALLS
AND MOST OF NW IA IN AREA FOR ISOLATED CONVECTION.
THERE IS ENOUGH INSTABILITY...CAPES BETWEEN 1000 AND 1500 J/KG TO
SUPPORT AT LEAST SMALL HAIL ALTHOUGH...AS MENTIONED IN THE
PREVIOUS DISCUSSION...WITH EFFECTIVE SHEAR AROUND 20 KTS...STORMS
WILL NOT BE ORGANIZED. IN ADDITION...SFC TO 3 KM THETA-E
DIFFERENCE WILL EXCEED 20 K. THE FLOW AROUND 3 KM IS ONLY 10 TO 15
KTS SO NOT A LOT OF MOMENTUM TO BRING DOWN BUT WITH THE POSSIBLE
ACCELERATION OF AIR PARCELS IN THE DOWNDRAFT...A FEW GUSTS TO 30
OR 40 MPH ARE POSSIBLE AS STORMS COLLAPSE. IN ADDITION...WITH
LIGHT SYNOPTIC SCALE WINDS...OUTFLOW BOUNDARIES ARE LIKELY TO
SPREAD OUT FROM CONVECTION AND MAY INCREASE WIND SPEEDS
TEMPORARILY MILES FROM ANY ACTUAL RAIN.
UPDATED GRIDS SENT. WILL BE UPDATING HWO TO ADD THREAT OF SMALL
HAIL AND STRONGER WIND GUSTS TO TODAY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT SUN AUG 3 2014
LAST OF THE OVERNIGHT CONVECTION IS PULLING OUT OF OUR CWA VERY
EARLY THIS MORNING AS THE ASSOCIATED SHORTWAVE DROPS INTO SOUTHERN
IOWA. WITH THE DEPARTURE OF THIS CONVECTION THINK THAT MUCH OF THE
REMAINDER OF THE MORNING AND AFTERNOON WILL BE DRY IN THE ABSENCE OF
ANY SIGNIFICANT FORCING...UNTIL LATER AFTERNOON WHEN A WEAK BOUNDARY
BEGINS TO DROP OUT OF NORTHERN SOUTH DAKOTA. AS ANOTHER SHORTWAVE
FALLS SOUTHWARD THROUGH WESTERN MINNESOTA ON A NORTHWESTERLY UPPER
LEVEL FLOW...MAY GET ENOUGH INTERACTION WITH THE FRONT TO AGAIN KICK
OFF ISOLATED CONVECTION IN OUR EAST IN THE LATE AFTERNOON AND
EVENING...THOUGH MODELS WOULD SUGGEST THAT THE BETTER ACTIVITY WILL
REMAIN TO THE EAST OF OUR CWA. WHILE MODERATE INSTABILITY WILL EXIST
IN THE VICINITY OF THE BOUNDARY...EFFECTIVE SHEAR REMAINS WEAK...SO
WOULD NOT EXPECT ANY REAL ORGANIZATION TO ANY STORMS THAT DEVELOP
AND THINKING THAT ANY SEVERE THREAT IS MINIMAL. AS FOR TEMPERATURES
TODAY...850 MB THERMAL PROFILES ARE SIMILAR TO YESTERDAY AND LOOKING
AT HIGHS ONCE AGAIN IN THE 80S...CLOSING IN ON 90 THROUGH SOUTH
CENTRAL SOUTH DAKOTA.
BY TONIGHT ANY ISOLATED CONVECTION THAT DEVELOPS IN OUR EAST WILL
TREND DOWNWARD THROUGH THE LATER EVENING/EARLY NIGHT TIME HOURS AS
THE ASSOCIATED SHORTWAVE PULLS AWAY FROM THE AREA. IT WILL BE
ANOTHER MILD NIGHT WITH LOWS IN THE LOWER 60S.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 345 AM CDT SUN AUG 3 2014
SUBTLE UPPER WAVE SLIDES SOUTHEAST ACROSS NORTHEAST PORTIONS OF THE
AREA MONDAY. WITH THIS REGION NEAR AXIS OF LOW LEVEL RIDGE...WILL
LIKELY SEE FAIRLY HIGH CLOUD BASES. HOWEVER THESE WEAK WAVES HAVE
BEEN ABLE TO TRIGGER SPOTTY ACTIVITY RECENTLY AND SEE NO REASON WHY
MONDAY SHOULD BE ANY DIFFERENT. MID LEVEL INSTABILITY IS NOT OVERLY
IMPRESSIVE...SO WOULD NOT EXPECT ANY SEVERE STORMS TO DEVELOP.
ATTENTION THEN TURNS TO MORE SIGNIFICANT SYSTEM SET TO AFFECT THE
REGION. FIRST EXPECT ISOLATED TO SCATTERED ELEVATED ACTIVITY MONDAY
NIGHT/TUESDAY WITH THE INITIAL SURGE OF WARM ADVECTION. THIS WILL BE
FOLLOWED TUESDAY NIGHT/WEDNESDAY BY FIRST REAL POTENTIAL FOR MORE
WIDESPREAD...POSSIBLY HEAVY...PRECIPITATION THAT THE REGION HAS SEEN
IN QUITE A WHILE. SEEING SOME DISAGREEMENT IN THE MODELS REGARDING
NORTH-SOUTH PLACEMENT OF THEIR RESPECTIVE PRECIPITATION OUTPUT...BUT
LARGE SCALE FORCING FROM DEEP WARM ADVECTION/ISENTROPIC LIFT/THETA-E
ADVECTION SEEM TO SHOW BETTER CONSENSUS...WHICH CURRENTLY POINTS TO
BETTER CHANCES BETWEEN MISSOURI VALLEY AND I-90 CORRIDOR. THIS LENDS
SOME CONFIDENCE IN BUMPING POPS IN THESE AREAS UP INTO CATEGORICAL
RANGE FOR TUESDAY NIGHT...THOUGH AT THIS TIME LOOKS LIKE FAIRLY GOOD
POTENTIAL FOR AT LEAST MEASURABLE PRECIP OVER MOST OF THE FORECAST
AREA.
SYSTEM WILL GRADUALLY PULL AWAY FROM THE REGION ON WEDNESDAY...AFTER
WHICH TIME MODEL CONSENSUS DIMINISHES AS WELL. MODELS DO GENERALLY
AGREE THAT LONGER RANGE...WEDNESDAY THROUGH SATURDAY...WILL START
OFF ON THE COOL SIDE WITH HIGHS LARGELY BACK IN THE 70S WEDNESDAY
AND THURSDAY. MORE PROGRESSIVE GFS THEN A LITTLE FASTER IN EXPANDING
WARMER AIR BACK INTO THE REGION...ACCOMPANIED BY FAIRLY WET PATTERN
FOR FRIDAY/SATURDAY. MEANWHILE ECMWF/GEM HOLD ONTO COOLER LOW LEVEL
FLOW...WHILE KEEPING THINGS DRY WITH RIDGING ALOFT. GIVEN THESE
DISCREPANCIES...HAVE NOT STRAYED FAR FROM BROAD CONSENSUS GRIDS FOR
THE LATTER PART OF THE FORECAST PERIOD...SHOWING A SLOW WARMING
TREND WITH LOW PRECIP CHANCES EACH DAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1244 PM CDT SUN AUG 3 2014
SMALL CHANCES FOR THUNDERSTORMS THROUGH 18Z MONDAY ARE THE MAIN
CONCERN. WHILE THERE IS NO STRONG SYSTEM TO ORGANIZE CONVECTION A
WEAK WAVE THIS AFTERNOON AND ANOTHER LATE TONIGHT AND MONDAY
MORNING WILL BRING SMALL CHANCES OF THUNDERSTORMS. IN THE CASE OF
THIS AFTERNOON...THIS CHANCE WILL BE PRIMARILY EAST OF I-29
ALTHOUGH A STORM COULD OCCUR AS FAR WEST AS KFSD. LATE TONIGHT AND
MONDAY MORNING...THERE WILL BE A LOW PROBABILITY OF STORMS
BEGINNING AROUND KHON AND SPREADING SOUTHEAST TOWARD KFSD AND KSUX
ON MONDAY MORNING. BUT WITH LOW PROBABILITIES FOR CONVECTION AT
ANY TIME FOR TAF LOCATIONS...DID NOT INCLUDE IN FORECAST.
OTHERWISE LIGHT WINDS AND VFR CONDITIONS EXPECTED THROUGH 18Z MONDAY.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...SCHUMACHER
SHORT TERM...JM
LONG TERM...JH
AVIATION...SCHUMACHER
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1120 AM MDT SUN AUG 3 2014
.UPDATE...
ISSUED AT 856 AM MDT SUN AUG 3 2014
A WEAK WAVE CONTINUES TO MOVE THROUGH THE WESTERN DAKOTAS...PRODUCING
SOME LIGHT SHOWERS ACROSS NORTHEASTERN WYOMING AND FAR WESTERN
SOUTH DAKOTA. WINDS ACROSS THE AREA ARE LIGHT AND VARIABLE...AND
TEMPS ARE IN THE UPPER 60S AND LOWER 70S. UPDATED GRIDS TO
INCREASE POPS SLIGHTLY AND TWEAK SKY GRIDS. REST OF FORECAST LOOKS
FINE AT THIS TIME.
&&
.SHORT TERM...TODAY THROUGH MONDAY NIGHT
ISSUED AT 259 AM MDT SUN AUG 3 2014
UPPER RIDGING CONTINUES ACROSS THE WESTERN CONUS WITH NW FLOW
CROSSING THE NRN PLAINS. WEAK UPPER WAVES CONTINUE TO ROUND THE TOP
OF THE RIDGE OVER THE NRN ROCKIES INTO THE NRN HIGH PLAINS. WV
IMAGERY SHOWS AN UPPER WAVE NOW CROSSING ERN MT BRINGING SHOWERS TO
SE MT. HRRR SHOWS THESE SHOWERS MAKING INTO FAR NE WY THRU NW SD
BEFORE 18Z SO HAVE ADDED SL CHC POPS THERE. MLCAPE FORECAST TO BE
500-1000 J/KG AGAIN TODAY...BUT BETTER LL SHEAR DEVELOPS LATE
AFTN/EVNG AS SFC LOW DEVELOPS JUST NW OF THE CWA. COULD SEE ISOLATED
STRONG STORMS OR PERHAPS A SVR STORM OR TWO.
WRN CONUS RIDGE BREAKS DOWN MONDAY AS UPPER LOW SLIDES INTO GREAT
BASIN. MONSOONAL STORMS WILL DEVELOP ACROSS WY AND BLKHLS...THEN
CROSS INTO THE CWA PLAINS THROUGH THE EVNG. MLCAPE OF 500-1000 AGAIN
EXPECTED...BUT THIS TIME WITH WEAKER AVAILABLE SHEAR. SEVERE STORMS
ARE NOT EXPECTED MON/MON NIGHT.
&&
.LONG TERM...TUESDAY THROUGH SATURDAY
ISSUED AT 259 AM MDT SUN AUG 3 2014
ACTIVE SW FLOW WILL DEVELOP BY TUESDAY...WITH DAILY CHANCE FOR
SHRA/TS THROUGH MOST OF THE WEEK...AS THE NE PAC NEGATIVE HEIGHT
ANOMALY SUPPORTS NUMEROUS LOW AMPLITUDE IMPULSES INTO THE FLOW AND
THE WESTERN RIDGE BREAKS DOWN. MOST ACTIVITY IS EXPECTED TO A HAVE
A STRONG DIURNAL COMPONENT...SUPPORTING THE HIGHEST CHANCES FOR
PRECIP IN THE AFTERNOON PERIODS...AND ESP OVER THE BLACK HILLS
GIVEN OROGRAPHIC INFLUENCES. GENERAL WSW FLOW WILL PERSIST INTO
THE WEEKEND WITH NO NOTED HIGH LATITUDE BLOCKING FAVORED IN MEAN
MODEL AND ENSEMBLE SOLUTIONS UNTIL EARLY NEXT WEEK WHEN THE
EASTERN NOAM UPPER TROUGH MAY MAKE A RETURN.
CARRIED AT LEAST A SLIGHT CHANCE POP MENTION THROUGH THE
PERIOD...RETAINING HIGHER NUMBERS TUESDAY THROUGH WED GIVEN
CONSISTENT SIGNALS FOR ADVECTING IMPULSES WITH APPRECIABLE LL
MOISTURE/WEAK CAPPING/AND A STALLED FRONTAL BOUNDARY OVER THE
REGION. RETAINED HIGHEST NUMBERS OVER THE BLACK HILLS...ESP TUE AND
WED. GENERAL WEAK 0-8 KM FLOW WITH PW VALUES IN EXCESS OF 1 INCH
MOST PLACES WILL SUPPORT AN INCREASED CHANCE FOR HEAVY
RAINFALL...ESP IN THE NORTHERN BLACK HILLS. SOME STRONG TO SEVERE
STORMS CANNOT BE RULED OUT IN THE PERIOD GIVEN POTENTIAL INCREASE IN
MID LEVEL FLOW AND POTENTIAL LL MOISTURE...ESP EARLY IN THE PERIOD.
TEMPERATURES ARE EXPECTED TO BE ON THE COOL SIDE OF SEASONAL NORMS
THROUGH MOST OF THE WEEK. LL EASTERLY FLOW/INCREASED CHANCES FOR
RAIN/AND INCREASED CLOUD COVER ARE ALL EXPECTED TO SUPPORT COOLER
TEMPS. HAVE CONTINUED TO NUDGE TEMPS DOWN TUES GIVEN MODEL/MOS
TRENDS. WARMER WEATHER LOOKS TO RETURN BY THE END OF THE WEEK AS BL
DRYING OCCURS UNDER HEIGHT RISES AND THERMAL RIDGING.
&&
.AVIATION...FOR THE 18Z TAFS THROUGH 18Z MONDAY
ISSUED AT 1120 AM MDT SUN AUG 3 2014
VFR CONDITIONS EXPECTED THROUGH THE PERIOD FOR MOST PLACES. ISOLD
TSRA WITH SCT -SHRA POSSIBLE THIS AFTERNOON/EVENING...ESPECIALLY
OVER THE BLKHLS. LCL MVFR VSBY AND GUSTY WINDS ARE POSSIBLE IN
HEAVIER CELLS. ISOLD SHRA/TS WILL LINGER THROUGH TONIGHT ACROSS
THE WESTERN HALF OF SD.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
UPDATE...POJORLIE
SHORT TERM...13
LONG TERM...JC
AVIATION...MLS
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
147 PM CDT SUN AUG 3 2014
.UPDATE...
CONVECTIVE TEMPS HAVE REMAINED IN THE MID 80S FOR MUCH OF THE DAY.
THIS TEMPERATURE HAS BEEN REACHED AND WE ARE SEEING SOME CU
DEVELOPMENT OVER THE LAST COUPLE OF HOURS. WILL GO AHEAD AND
INCREASE THE CLOUD COVER TO PARTLY CLOUDY FOR THE REMAINDER OF
TODAY. OTW...CAPE VALUES ARE QUITE LOW AND THE DEVELOPMENT OF
CONVECTIVE PRECIP IS NOT EXPECTED. THE HRRR DOES ELUDE TOWARD A
SHOWER OR TWO POPPING UP ACROSS SOUTH CENTRAL AREAS LATER THIS
AFTERNOON. BUT COVERAGE SHOULD BE AT OR LESS THAN 10 PERCENT AND
SHORT LIVED.
&&
.PREV DISCUSSION... /ISSUED 1225 PM CDT SUN AUG 3 2014/
AVIATION 18Z DISCUSSION...NORTHWESTERLY FLOW WILL ALLOW DRIER AIRMASS TO
REMAIN ACROSS THE TAF AREAS THROUGH THE NEXT 24 HOURS. THIS WILL
KEEP CAPE VALUES AT A MINIMUM AND AS A RESULT...MOSTLY CLEAR SKIES
AND DRY WEATHER IS EXPECTED TO CONTINUE. OTW...SOME LIGHT FOG MAY
OCCUR AT CSV LATE TONIGHT.
PREV DISCUSSION... /ISSUED 643 AM CDT SUN AUG 3 2014/
UPDATE...FOR 12Z AVIATION FORECASTS.
AVIATION...
AT CKV AND CSV...VFR THR0UGH 07Z/04, THEN BECOMING MVFR DUE TO BR.
AT BNA...VFR CONDITIONS EXPECTED THROUGH THE FORECAST PERIOD.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1113 AM CDT SUN AUG 3 2014
.UPDATE...SPS MESO PLOTS SHOW DESTABILIZATION ACROSS SRN WITH ML
CAPE VALUES ALREADY TO AROUND 1000 J/KG. PRIMARY SHORTWAVE IS
TRACKING FROM SE IA INTO WC IL. HOWEVER AN EXTENSION OF THIS VORT
EXTENDS INTO SC WI. MESO MODELS CONTINUE TO SHOW A FAIR AMOUNT OF
DEVELOPMENT THIS AFTERNOON...BUT A FORMIDABLE TRIGGER IS TOUGH TO
LATCH ONTO. IN THE LOW LEVELS THERE REALLY IS NOTHING. BUT WE ARE
EXPECTING THE LAKE BREEZE TO POSSIBLY SERVE AS A FOCUS. THERE
JUST ISN/T MUCH GOING ON UPSTAIRS OUTSIDE OF THIS WEAK VORT AXIS.
THE RAP SOUNDINGS APPEAR TO BE UNDERDOING THE CAPE WITH THE NAM
SOUNDINGS MATCHING UP MORE WITH THE SPC MESO ANALYSIS. THE 12Z NAM
AND 00Z ECMWF ARE BASICALLY DRY FOR THIS AFTERNOON. ALSO THE
MAV/MET GUIDANCE HAS VERY LOW POPS FOR THIS AFTERNOON. AT THIS
POINT WILL TREND POPS A SMIDGE LOWER AND GO WITH MORE ISOLD/SCT
DEVELOPMENT. SHEAR AND MID LEVEL LAPSE RATES ARE NON-EXISTENT SO
SVR POTENTIAL VERY LOW. ALSO 500 MILLIBAR TEMPS ARE -12C...SO
NOT AS COLD AS YESTERDAY AND FRIDAY.
PC
&&
.AVIATION/18Z TAFS/...MAIN FOCUS IS ON COVERAGE OF CONVECTION THIS
AFTERNOON. WEAK VORT AXIS EXPECTED TO MOVE THROUGH. STARTING TO
SEE SOME CU POPPING. AIRMASS IS DESTABILIZING SO GOING WITH
ISOLD/SCT DEVELOPMENT WITH SOME COOL AIR ALOFT AS WELL. WILL KEEP
MUCH OF THIS FORECAST PERIOD VFR WITH PATCHY FOG POSSIBLE ONCE
AGAIN LATER TONIGHT. FRONTAL BOUNDARY SAGS INTO SRN WI MONDAY WITH
MORE NOTABLE SHORTWAVE ACTIVITY MOVING CLOSER FROM NRN WI AFFECTING
THE AREA SO MAY SEE MORE COVERAGE ON THE STORMS FOR MON AFTN/EVE.
PC
&&
.PREV DISCUSSION... /ISSUED 338 AM CDT SUN AUG 3 2014/
TODAY AND TONIGHT...FORECAST CONFIDENCE MEDIUM.
THE CORE OF THE SHORTWAVE TROUGH OVER IA WILL TRACK TO THE SOUTH
BUT THE NORTHERN EXTENSION WILL SLOWLY MOVE ACROSS SRN WI THROUGH
THE DAY. MLCAPE WILL RANGE FROM 500-1000 J/KG WITH LITTLE TO NO
CAPPING. GIVEN THE TSTORM ACTIVITY THAT HAS OCCURRED FOR THE LAST
SEVERAL DAYS...WOULD EXPECT SCT TSTORMS THIS AFTERNOON INTO THE
EVENING WITH THE BEST FOCUS OVER THE NRN CWA AND ALONG THE LAKE
BREEZE FRONT. ANOTHER SHORTWAVE TROUGH WILL APPROACH FROM THE NW
LATE TNT ALONG WITH A WEAK COLD FRONT FROM THE NORTH...SO ISOLD TO
SCT SHOWERS AND STORMS WILL REMAIN IN THE FORECAST. SMALL HAIL
WILL LIKELY OCCUR WITH THE TSTORMS THIS AFTERNOON. HIGH TEMPS WILL
BE SIMILAR TO YESTERDAY BUT WARMER NEAR THE LAKE AS THE LAKE
BREEZE DEVELOPS LATER.
MONDAY AND TUESDAY...FORECAST CONFIDENCE...MEDIUM
A WEAK INVERTED SURFACE TROUGH IS EXPECTED TO KICK OFF MORE
SHOWERS AND THUNDERSTORMS ON MONDAY. STORM MOTION WILL BE A LITTLE
HIGHER THAN THE LAST FEW DAYS...UP AROUND 15 TO 20 KNOTS...SO THE
STORMS SHOULD BE ABLE TO COVER A LITTLE MORE GROUND. BETWEEN THIS
AND PLENTY OF INSTABILITY AND MOISTURE...DECIDED TO GO LIKELY POPS
MOST PLACES.
KEPT CHANCE POPS FOR MONDAY NIGHT AS A SHORTWAVE PUSHES THROUGH.
WENT WITH ONLY SLIGHT CHANCE POPS TUESDAY...GOING DRY IN THE
NORTHEAST AS A MUCH DRIER AIRMASS MOVES IN UNDER HIGH PRESSURE.
SHOULD SEE TEMPS RIGHT AROUND NORMAL FOR MONDAY AND TUESDAY.
WEDNESDAY THROUGH SATURDAY...FORECAST CONFIDENCE...MEDIUM
MODELS SEEM TO BE FINALLY SETTLING ON A SOLUTION FOR THE SECOND
HALF OF THE WEEK...BRINGING UPPER RIDGING AND SURFACE HIGH
PRESSURE IN FOR MOST OF THIS PERIOD. KEPT A LITTLE POPS HERE AND
THERE...THOUGH THESE WILL LIKELY NEED TO BE DROPPED IN THE FUTURE
IF MODELS ARE PERSISTENT WITH FORECASTING THIS PATTERN.
OTHERWISE...THIS SETUP SHOULD RESULT IN DRY WEATHER...WITH A GOOD
AMOUNT OF SUNSHINE AND TEMPS NEAR TO A FEW DEGREES ABOVE NORMAL.
AVIATION/12Z TAFS/...SCT-BKN050 WILL DEVELOP BY LATE MORNING AND
LAST THROUGH THE REMAINDER OF THE DAY AND INTO MUCH OF SUN NT AS A
COUPLE UPPER LEVEL DISTURBANCES AFFECT THE REGION. SCT TSTORMS ARE
MAINLY EXPECTED THIS AFTERNOON WITH ISOLD TO SCT TSTORMS TNT. PATCHY
FOG WILL OCCUR THROUGH SUNRISE THIS MORNING AND WILL AFFECT KMSN.
OTHERWISE PATCHY FOG IS POSSIBLE AGAIN LATE SUN NT AND MAY AFFECT
KMSN...KUES...KENW.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...GEHRING
MONDAY THROUGH SATURDAY...DDV