Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/26/15
AREA FORECAST DISCUSSION...UPDATED
NWS LITTLE ROCK AR
630 PM CDT THU JUN 25 2015
.AVIATION...
ISOLATED TSRA WILL DISSIPATE...WITH VFR CONDITIONS PREVAILING
DURING THE OVERNIGHT HOURS. A LINE OF TSRA WILL DEVELOP TO THE
NORTHWEST AFTER 26/15Z...AND WILL MOVE INTO THE STATE DURING THE
DAY. HAVE ADDED VCTS/PROB30 GROUPS FOR THE END OF THIS TAF CYCLE.
&&
.PREV DISCUSSION... /ISSUED 220 PM CDT THU JUN 25 2015/
SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT
TODAY...HAVE CONTINUED TO SEE A FEW CLOUDS BEGIN TO POP IN THE HEAT
OF THE DAY...GENERALLY ACROSS SOUTHERN ARKANSAS. WITHIN THE PAST
HOUR OR TWO... HAVE BEGUN TO SEE A FEW SHOWERS AND THUNDERSTORMS
FIRE IN NORTHERN LOUISIANA. AT THIS TIME...DO HAVE POPS ACROSS
SOUTHERN ARKANSAS. HRRR SUGGESTS STORMS COULD FIRE AS FAR NORTH AS
LITTLE ROCK...BUT DO HAVE SOME DOUBTS THAT CENTRAL ARKANSAS WILL SEE
RAIN. AS A RESULT...KEPT SLIGHT CHANCE POPS LIMITED TO SOUTHERN
ARKANSAS.
UPPER LEVEL RIDGE HAS BEGUN TO RETROGRADE TO THE WEST WITH WESTERLY
FLOW SETTING UP ALOFT. NORTHWESTERLY FLOW WILL BE MOVING INTO THE
REGION AND HELP TO DRIVE A FRONT INTO THE STATE ON FRIDAY. 12Z WRF
SUGGESTS PRECIP WILL BE IN PLACE ACROSS NORTHERN ARKANSAS BEFORE 12Z
ON FRIDAY. DO THINK THE FRONT WILL BE A BIT QUICKER THAN THE MODELS
SUGGEST...BUT BELIEVE THE WRF IS MUCH TOO QUICK. THEREFORE JUST KEPT
CHANCE POPS MENTIONED ACROSS NORTHERN ARKANSAS DURING THE MORNING
HOURS.
AMPLE CAPE WILL BE AVAILABLE AHEAD OF THE FRONT ON FRIDAY WITH DEEP
LAYER SHEAR AROUND 30 KNOTS. MID LEVEL LAPSE RATES...WILL NOT BE
OUTRAGEOUS...BUT DO EXPECT DAMAGING WIND GUSTS TO BE THE PRIMARY
THREAT.
IT DOES APPEAR THE COLD FRONT WILL CLEAR THE STATE BY MID MORNING ON
FRIDAY WITH DRY AND NOTICEABLY COOLER AND DRIER AIR FILTERING INTO
THE STATE. DRY WEATHER WILL BE SHORT LIVED AS THE NEXT CHANCE FOR
PRECIPITATION MOVES INTO NORTHERN ARKANSAS AS THE SHORT TERM ENDS.
LONG TERM...MONDAY THROUGH THURSDAY
FLOW ALOFT WILL BE FROM THE NW OVER THE REGION AT THE START OF THE
LONG TERM PERIOD AS AN ELONGATED UPPER RIDGE WILL BE OVER THE
ROCKIES...WITH A TROUGH OVER THE GREAT LAKES REGION. A NEW COLD
FRONT WILL SLOW OVER PORTIONS OF THE STATE...WITH CHANCES FOR
SHOWERS AND THUNDERSTORMS RETURNING. INITIALLY...BEST POPS WILL BE
ACROSS THE NRN COUNTIES...BUT DO THINK SOME CHANCES FOR PRECIP WILL
EXIST FURTHER SOUTH BY LATE MON INTO TUE WITH THE FRONT WASHING OUT.
SRLY FLOW WILL RETURN FOR TUE AND THROUGH MUCH OF THE REST OF THE
FORECAST...WHICH WILL ALLOW FOR TEMPS TO INCREASE FROM JUST BELOW
NORMAL...TO AROUND NORMAL FOR MUCH OF NEXT WEEK. CHANCES FOR
DIURNALLY DRIVEN CONVECTION WILL BE SEEN...ESPECIALLY WITH THE UPPER
RIDGE REMAINING WEST OF THE STATE...AND AR IN GENERAL NW FLOW ALOFT.
BY THE END OF NEXT WEEK...ANOTHER COLD FRONT WILL ATTEMPT TO MOVE
INTO THE STATE...WITH ANOTHER SHOT OF COOLER AIR AND MORE CHANCES
FOR PRECIP.
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AVIATION...58
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
227 PM CDT WED JUN 24 2015
.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT
QUITE A BIT OF CLOUDS HAVE BEEN POPPING UP AROUND THE STATE TODAY
WITH TEMPS AND DEW POINTS FAIRLY SIMILAR TO WHAT WAS SEEN YESTERDAY.
HAVE ALREADY BEGAN TO SEE A FEW SHOWERS AND THUNDERSTORMS FIRE ALONG
THE MISSISSIPPI RIVER...AND THEREFORE HAVE ADDED POPS TO MUCH OF THE
EASTERN PORTIONS OF THE CWA. BOTH HRRR AND WRF AGREE POP UP SHOWERS
AND THUNDERSTORMS WILL BE POSSIBLE IN EASTERN ARKNASAS...HOWEVER DO
BELIEVE THE BETTER CHANCES FOR PRECIPITATION WILL REMAIN EAST OF THE
RIVER AND THUS JUST HAVE SLIGHT CHANCE POPS AT THIS TIME.
SIMILAR CONDITIONS WILL BE EXPECTED ON THURSDAY WITH CHANCES FOR
DIURNALLY DRIVEN PRECIPITATION ACROSS SOUTHERN AND EASTERN ARKANSAS.
CONDITIONS WILL ONCE AGAIN BE HOT AND HUMID ON THURSDAY...SO A HEAT
ADVISORY WILL ONCE AGAIN BE IN EFFECT.
ATTENTION THEN SHIFTS TO FRIDAY AS THE UPPER LEVEL RIDGE RETROGRADES
TO THE WEST AND NW FLOW ALOFT DRIVES A COLD FRONT INTO THE STATE
LATE FRIDAY AND INTO SATURDAY. SHOWERS AND THUNDERSTORMS WILL
DEVELOP AHEAD OF THE FRONT FRIDAY AFTERNOON AND EVENING...RESULTING
IN CHANCES FOR STRONG TO SEVERE THUNDERSTORMS. THE MAIN THREATS WITH
THESE STORMS WOULD BE DAMAGING WINDS.
DO BELIEVE THE COLD FRONT WILL CLEAR THE STATE BY MID DAY ON
SATURDAY WHICH IS A LITTLE EARLIER THAN PREVIOUSLY ADVERTISED. AS A
RESULT...DID BEGIN TO TREND POPS DOWN SATURDAY MORNING AND REMOVE
THEM SATURDAY AFTERNOON. THIS SETS THE STAGE FOR COOLER AND DRY AIR
IN THE FORECAST FOR THE LONG TERM.
&&
.LONG TERM...SUNDAY THROUGH THURSDAY
UPPER AIR PATTERNS ACROSS NORTH AMERICA WILL BE WELL AMPLIFIED AT
THE START OF THIS PERIOD...WITH A 2 SIGMA RIDGE CENTERED OVER THE
NORTHERN ROCKIES...AND A 2 SIGMA TROUGH CENTERED OVER THE OHIO
VALLEY. WELL BELOW NORMAL TEMPERATURES ARE EXPECTED A THE START OF
THE PERIOD...WITH A SLOW WARMING TREND EXPECTED THEREAFTER...AS
THE PATTERN DEAMPLIFIES.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 74 95 74 90 / 20 20 30 60
CAMDEN AR 73 96 75 92 / 20 20 10 40
HARRISON AR 71 93 71 85 / 10 10 30 60
HOT SPRINGS AR 74 97 75 92 / 20 10 10 50
LITTLE ROCK AR 76 96 76 93 / 20 10 20 50
MONTICELLO AR 76 96 75 93 / 20 20 20 40
MOUNT IDA AR 70 95 73 91 / 10 10 10 50
MOUNTAIN HOME AR 71 95 71 86 / 10 20 30 60
NEWPORT AR 74 96 74 90 / 20 20 30 60
PINE BLUFF AR 75 96 74 92 / 20 20 20 50
RUSSELLVILLE AR 72 96 73 92 / 10 10 20 60
SEARCY AR 73 95 74 92 / 20 10 20 60
STUTTGART AR 76 96 75 92 / 20 20 20 50
&&
.LZK WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 6 PM CDT THIS EVENING FOR ARKANSAS-BRADLEY-
CALHOUN-CLEBURNE-CLEVELAND-DALLAS-DESHA-DREW-FAULKNER-GRANT-
INDEPENDENCE-JACKSON-JEFFERSON-LINCOLN-LONOKE-MONROE-PRAIRIE-
PULASKI-SALINE-WHITE-WOODRUFF.
HEAT ADVISORY FROM 1 PM TO 6 PM CDT THURSDAY FOR ARKANSAS-
BRADLEY-CALHOUN-CLEBURNE-CLEVELAND-DALLAS-DESHA-DREW-FAULKNER-
GRANT-INDEPENDENCE-JACKSON-JEFFERSON-LINCOLN-LONOKE-MONROE-
PRAIRIE-PULASKI-SALINE-WHITE-WOODRUFF.
&&
$$
SHORT TERM...65 / LONG TERM...55
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
859 PM MDT THU JUN 25 2015
.UPDATE...
ISSUED AT 858 PM MDT THU JUN 25 2015
ISOLATED SEVERE STORMS CONTINUE AT THIS HOUR BUT OVERALL TREND
WILL BE WEAKENING THROUGH LATE EVENING AS STORMS EVENTUALLY MOVE
BACK INTO AREAS ALREADY WORKED OVER BY EARLIER STORMS.
HOWEVER...STILL EXPECT A FEW SHOWERS AND STORMS TO CONTINUE
THROUGH THE NIGHT. OVERALL ONLY MINOR CHANGES MADE TO EXISTING
FORECAST.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 330 PM MDT THU JUN 25 2015
CONVECTION BEGINNING OVER THE HIGHER TERRAIN AND LARIMER COUNTY AS
A SHORTWAVE MOVES CLOSER OUT WYOMING. A LONG LIVED
MCS....MESOSCALE CONVECTIVE SYSTEM HAS BEEN MOVING SOUTHEAST FROM
WYOMING AND INTO NEBRASKA ALL DAY....AND OUTFLOW FROM THIS SYSTEM
WILL LIKELY HELP KICK OFF ADDITIONAL CONVECTION THIS EVENING.
DEWPOINTS IN THE UPPER 50S TO LOWER 60S ALONG WITH TEMPERATURES IN
THE MID TO UPPER 80S ARE HELPING CAPES REACH IN THE 1000-2000 J/KG
AND UPWARDS OF 3000 NEAR THE WY/NE BORDER. SHEAR IS EXPECTED TO
INCREASE TO 35 KTS TO NEAR 50 KTS NEAR THE WYOMING BORDER. THESE
INGREDIENTS ARE COMBINING TO BRING THE THREAT OF SEVERE
WEATHER...MAINLY FOR LARGE HAIL AND DAMAGING OUTFLOW WINDS TO THE
PLAINS TONIGHT. BEST AREA IS ALONG AND EAST OF A LINE FROM GREELEY
TO LIMON. HOWEVER OUTFLOW FROM STORMS...IN ADDITION TO ENHANCED UPSLOPE
FLOW THIS EVENING MAY PRODUCE OTHER STORM FURTHER WEST. SEVERE
THUNDERSTORM WATCH HAS BEEN ISSUED FOR MOST OF THE PLAINS AND
URBAN CORRIDOR FOR THIS REASON. ACTIVITY UP NEAR CHEYENNE HAS
BEEN PROGGED BY THE LATEST HRRR MODEL TO BECOME THE LONG
ADVERTISED POSSIBLE MCS SYSTEM TO PUSH SOUTHEAST OVER NORTHEASTERN
COLORADO AND INTO KANSAS BY MIDNIGHT. THE OUTFLOW FROM THIS SYSTEM
IS EXPECTED TO PUSH BACK TOWARD THE FOOTHILLS TO BRING STRATUS AND
SOME FOG OVER THE PLAINS OVER NIGHT. SO EVEN THOUGH TEMPERATURES
SHOULD BE COOLING TONIGHT AND INTO TOMORROW...MINIMUM TEMPERATURES
WILL BE MODERATED OVER THE PLAINS UNDER WHAT STRATUS FORMS.
STRATUS WILL LIKELY STICK IN ALONG THE URBAN CORRIDOR AND PALMER
DIVIDE FOR MOST OF TOMORROW. THIS WILL ALLOW FOR TEMPERATURES
ABOUT 5 TO 10 DEGREES COOLER THAN TODAY. EXPECT AFTERNOON SHOWERS
AND THUNDERSTORMS TO FIRE OFF THE MOUNTAINS ABOVE THE STABLE
STRATUS DECK FIRST...THEN SOME MAY PUSH EAST DURING THE LATE
AFTERNOON OVER THE URBAN CORRIDOR AND ADJACENT PLAINS. WITH THE
UPPER RIDGE PUSHING IN FROM THE WEST SLIGHTLY MORE...THIS MAY
LIMIT CONVECTION OVER THE PLAINS.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 330 PM MDT THU JUN 25 2015
THE MAIN MESSAGE CONTINUES TO BE UPPER LEVEL RIDGING OVER THE
GREAT BASIN DURING THE PERIOD. THIS PUTS OUR AREA UNDER A NORTH
TO NORTHWEST FLOW ALOFT WITH LITTLE IN THE WAY OF DISCERNIBLE QG
DYNAMICS AFFECTING OUR WEATHER. THIS ALSO KEEPS THE PLAINS
SUSCEPTIBLE TO OCCASIONAL OUTFLOWS AND FRONTAL SURGES FROM
CONVECTION THAT FORMS OVER THE GREAT PLAINS. ADDITIONALLY ENOUGH
MOISTURE WILL LIKELY BE CAUGHT IN THE RIDGE TO KEEP THE USUAL
DIURNAL CONVECTIVE CYCLE GOING. NWP BIAS-CORRECTED CONSENSUS
TEMPERATURES ARE PREDICTING SEASONAL VALUES BUT SOME OF THE LATEST
GUIDANCE IS SUGGESTING MUCH WARMER VALUES. WE SHALL SEE.
&&
.AVIATION...(FOR THE TAFS THROUGH 06Z FRIDAY EVENING)
ISSUED AT 858 PM MDT THU JUN 25 2015
ANOTHER BATCH OF CONVECTION DROPPING SOUTHWARD WILL KEEP THE
THREAT OF STORMS IN THE FRONT RANGE METRO AREA AIRPORTS THROUGH
06Z-07Z. STRONGER STORMS MAY STILL BE SEVERE WITH HAIL AND HEAVY
RAIN REDUCING VISIBILITIES. COULD SEE A FEW STORMS LINGER
OVERNIGHT...AND SOME HIGH RESOLUTION MODELS CONTINUE TO SHOW
ADDITIONAL ACTIVITY ALONG THE FOOTHILLS AND ADJACENT PLAINS. WILL
HAVE TO FOLLOW PROGRESSION OF STORMS AND ADJUST TAFS AS NECESSARY.
EXPECTING STRATUS/FOG TO PUSH IN OVER THE AREA AFTER 09Z. IFR
CONDITIONS POSSIBLE FROM 09-15Z...THEN MVFR CEILINGS MAY LAST
THROUGH 00Z.
&&
.HYDROLOGY...
ISSUED AT 330 PM MDT THU JUN 25 2015
STORMS MOVING RATHER QUICKLY THIS AFTERNOON AND EVENING WITH
RAINFALL AMOUNTS MAINLY UNDER ONE HALF INCH. HOWEVER...WITH A
RELATIVELY WET AIRMASS...COULD SEE LOCALLY HIGHER AMOUNTS UP TO
AN INCH OVER THE PLAINS. FOR THIS EVENING...WITH INCREASING
UPSLOPE FLOW ALONG THE FRONT RANGE...IF STORMS FIRE IN AND NEAR
THE FOOTHILLS...COULD SEE HEAVY RAINFALL DEVELOP OVER PORTIONS OF
THE URBAN CORRIDOR WITH RAINFALL AMOUNTS UP TO AN INCH OR TWO IN A
FEW LOCATIONS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BARJENBRUCH
SHORT TERM...KRIEDERMAN
LONG TERM...ET
AVIATION...BARJENBRUCH
HYDROLOGY...KRIEDERMAN
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
350 AM MDT WED JUN 24 2015
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 350 AM MDT WED JUN 24 2015
THE FLOW ALOFT WILL REMAIN NEARLY ZONAL TODAY THRU TONIGHT WITH SOME
MID LVL MOISTURE MOVING ACROSS THE AREA. EXPECT SCT TSTMS OVER THE
HIGHER TERRAIN THIS AFTN WITH WIDELY SCT ACTIVITY OVER THE VALLEYS.
OVER NERN CO AN OUTFLOW BNDRY FM CONVECTION OVER NWRN NEBRASKA AND
WRN SOUTH DAKOTA WILL EVENTUALLY MOVE INTO NERN CO BY MIDDAY AND
THEN MOVE WESTWARD INTO THE FRONT RANGE BY MID TO LATE AFTN IF HRRR
IS CORRECT. AHEAD OF THIS BNDRY WINDS ARE SUPPOSED TO BECOME MORE
WNW ALONG THE FRONT RANGE AS BEST INSTABILITY STAYS OVER THE FAR
NERN PLAINS FOR MOST OF AFTN. OVERALL NOT SURE HOW THINGS ARE GOING
TO EVOLVE THIS AFTN SO WILL KEEP WDLY SCT TSTMS OVER THE PLAINS.
BEST CHC FOR SVR LOOKS TO BE NE OF A LINE FM GREELEY TO FORT MORGAN
TO LIMON WITH MARGINAL LARGE HAIL AND STG WINDS.
AS FOR HIGHS WILL KEEP READINGS SIMILAR TO YESTERDAY AS 850-700 MB
TEMPS CHANGE LITTLE HOWEVER IF WNW DOWNSLOPE WINDS DO DVLP ALONG THE
FRONT RANGE HIGHS COULD END UP BEING A FEW DEGREES WARMER THAN FCST.
FOR TONIGHT TSTMS SHOULD END OVER THE HIGHER TERRAIN DURING THE
EARLY EVENING HOURS. OVER THE PLAINS MAY SEE SOME ACTIVITY LINGER
INTO THE MID EVENING HOURS WITH AN OUTSIDE CHC OF AN MCS CLIPPING
THE FAR NERN CORNER LATE TONIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 350 AM MDT WED JUN 24 2015
A TYPICAL SUMMER WEATHER PATTERN FOR COLORADO WILL BE IN PLACE
THROUGH THE FORECAST PERIOD...BRINGING TEMPERATURES AROUND
SEASONAL NORMALS AND A CHANCE OR SLIGHT CHANCE OF AFTERNOON
SHOWERS ACROSS THE FORECAST AREA EACH DAY. INITIALLY...MODERATE
WESTERLY FLOW ALOFT WILL BE IN PLACE AS AN UPPER RIDGE CONTINUES
OVER THE SOUTHEASTERN UNITED STATES. AT LOWER AND MID LEVELS...
MOISTURE AND INSTABILITY WILL BE MOVING INTO THE STATE FROM THE
SOUTHERN PLAINS. DAYTIME HEATING WILL DE-STABILIZE THE AIRMASS IN
THE AFTERNOONS...LEADING TO THUNDERSTORM DEVELOPMENT OVER THE
MOUNTAINS AND FOOTHILLS WHICH WILL DRIFT EASTWARD THROUGH THE
EARLY EVENINGS. ON THURSDAY NIGHT A SURFACE COLD FRONT WILL MOVE
INTO NORTHEAST COLORADO...WHICH WILL KEEP TEMPERATURES COOLER ON
FRIDAY. AT THE SAME TIME HIGH PRESSURE ALOFT OVER THE WESTERN U.S.
WILL STRENGTHEN...BRINGING COLORADO UNDER A MORE NORTHWESTERLY
FLOW ALOFT. GULF MOISTURE AT LOW AND MID-LEVELS WILL CONTINUE
MOVING INTO EASTERN COLORADO THROUGH THE WEEKEND AND EACH DAY WILL
BE A BALANCE BETWEEN WEAK SUBSIDENCE DOWNSTREAM FROM THE WESTERN
U.S. UPPER RIDGE AND DAYTIME HEATING OF THE AIRMASS PRODUCING THE
CHANCE OF AFTERNOON SHOWERS EACH DAY. THE NORTHWESTERLY FLOW AT
MID AND UPPER LEVELS COULD ASSIST IN THE DEVELOPMENT OF SHOWER
ACTIVITY DUE TO FAVORABLE VERTICAL WIND SHEAR PROFILES THAT WILL
RESULT. IN THE END...EACH DAY SHOULD SEE PLENTY OF SUNSHINE
THROUGH MORNING AND EARLY AFTERNOONS...AND THEN THE DEVELOPMENT OF
CLOUDS AND SHOWERS THROUGH THE LATE AFTERNOONS. THE EXCEPTION TO
THIS MAY BE FRIDAY MORNING WHEN STRATUS AND LOW CLOUDS WILL BE
POSSIBLE IN THE POST-FRONTAL AIRMASS. THIS WILL BE ADDRESSED IN
LATER FORECASTS.
&&
.AVIATION...(FOR THE TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 350 AM MDT WED JUN 24 2015
THERE IS A WK DENVER CYCLONE NR DIA SO EXPECT LOW CLOUDS AND SOME
FOG TO DVLP BY 11Z TO THE N AND NW OF THE AIRPORT. IF THE WINDS
BECOME LIGHT WNW THEN COULD SEE SOME STRATUS/FOG FOR A FEW HOURS
THRU 14Z AT DIA.
OTHERWISE EXPECT ISOLD TO WDLY SCT HIGHER BASED TSTMS WILL BE
POSSIBLE IN THE 21Z-01Z TIMEFRAME WITH GUSTY OUTFLOW WINDS.
AS FOR WINDS BOTH THE HRRR AND RAP SHOW WINDS BECOMING MORE WNW BY
15Z AND LASTING THRU 18Z. AFTER 18Z THEY DIVERGE AS THE RAP KEEPS
THEM MAINLY WNW THRU THE REST OF THE AFTN WHILE THE HRRR HAS THEM
BECOMING MORE ELY AS A WK BNDRY MOVES IN FM THE NE. FOR NOW WILL
TREND MORE WITH THE HRRR SOLUTION. FOR THIS EVENING WINDS SHOULD
GRADUALLY TREND TOWARDS TO MORE OF A SSW DIRECTION AND REMAIN
DRAINAGE OVERNIGHT.
&&
.HYDROLOGY...
ISSUED AT 350 AM MDT WED JUN 24 2015
STORMS WILL MOVE RATHER QUICKLY THIS AFTN AND EVENING SO RAINFALL
AMOUNTS SHOULD BE MAINLY UNDER A QUARTER INCH.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RPK
LONG TERM...DANKERS
AVIATION...RPK
HYDROLOGY...RPK
AREA FORECAST DISCUSSION
NWS NEW YORK NY
745 PM EDT THU JUN 25 2015
.SYNOPSIS...
WAVES OF LOW PRESSURE TRACK ALONG A STATIONARY FRONT DRAPED
ACROSS THE MID ATLANTIC STATES INTO SATURDAY. ANOTHER LOW WILL
TRACK FROM THE CENTRAL APPALACHIANS THROUGH SOUTHERN NEW ENGLAND
FROM SATURDAY NIGHT INTO SUNDAY. WEAK HIGH PRESSURE WILL FOLLOW
FOR LATER SUNDAY THROUGH MONDAY NIGHT. A COLD FRONT WILL PASS
THROUGH TUESDAY NIGHT INTO WEDNESDAY MORNING...FOLLOWED AGAIN BY
HIGH PRESSURE LATER WEDNESDAY THROUGH THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
LATEST SATELLITE TRENDS AND OBSERVATIONS SHOW CLOUD COVER OVER THE
AREA TO BE PREDOMINATELY OVERCAST DUE TO MID-HIGH CLOUDS. WITH NO
EXPECTATION OF MUCH OF A CHANGE IN CLOUD COVERAGE...WILL SEE A
LOWERING OF CLOUD BASE THOUGH...HAVE GONE WITH A CLOUDY FORECAST
FOR TONIGHT.
23Z OBS HAVE PRECIPITATION ONLY REACHING THE GROUND FROM A
HAZLETON-POTTSTOWN-PHILADELPHIA LINE...SO RADAR RETURNS REPRESENT
VIRGA FARTHER EAST. BASED ON THIS...SLOWED DOWN ONSET OF
PRECIPITATION THIS EVENING. FOR NOW IT APPEARS THE BEST CHANCE
FOR SHOWERS SHOULD COME LATE TONIGHT FROM A COMBINATION OF LOW
LEVEL LIFT/CONVERGENCE...PLUS LIFT VIA A PASSING MID LEVEL
SHORTWAVE TROUGH AND COUPLED UPPER LEVEL JET STREAKS. SO BASED ON
THIS LEFT POPS OVERNIGHT AT CATEGORICAL FOR NYC METRO...NE NJ AND
NEARBY PARTS OF THE LOWER HUDSON VALLEY...AND LIKELY ELSEWHERE.
LATEST RUC AND HRRR SUPPORT THIS LINE OF THINKING.
NIGHTTIME LOWS SHOULD BE MAINLY IN THE 60S.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
LIKELY/CAT POP TO START SHOULD TAPER OFF EARLY AS THE BEST UPPER
LEVEL FORCING MOVES EAST. THE AREA WILL STILL BE IN A FAVORABLE
UPPER JET REGION...SO THIS IN COMBINATION WITH ANOTHER PASSING MID
LEVEL SHORTWAVE AND DAYTIME HEATING/LOW LEVEL DESTABILIZATION
SHOULD RESULT IN SCT AFTERNOON SHOWERS...MAINLY NORTH AND WEST OF
NYC. WITH AREA IN THE COOL SECTOR EXPECT HIGHS ONLY IN THE MID AND
UPPER 70S.
CHANCES FOR PRECIPITATION WILL WANE FRI EVENING WITH LOSS OF
HEATING/DESTABILIZATION...AND MOST OF THE NIGHT SHOULD BE DRY AS
SHORTWAVE RIDGING QUICKLY MOVES ACROSS. COULD HOWEVER START TO SEE
LIGHT RAIN ENTER FAR WRN AREAS TOWARD DAYBREAK AS THE UPPER RIDGE
MOVES EAST...AND LOW PRESSURE BEGINS TO APPROACH FROM THE
OH VALLEY.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
LOW PRESSURE SYSTEM IS PROGGED TO SHIFT IN ON SATURDAY WITH A
SECONDARY LOW CENTER PROBABLY PASSING NEARBY OR THROUGH SUNDAY
MORNING. INCREASING ISENTROPIC LIFT AND MOISTURE WILL BRING
INCREASING POPS THROUGH THE DAY...WITH ALL AREAS LIKELY SEEING
RAINFALL BY LATE DAY. PW INCREASES AS WELL...AND WITH A LOW LEVEL JET
SHIFTING THROUGH...RAINFALL COULD BE HEAVY AT TIMES LATE IN THE
DAY AT LEAST OVER THE SW ZONES...THEN FOR THE ENTIRE CWA DURING
SATURDAY EVENING. ENOUGH ELEVATED INSTABILITY AND FORCING WARRANTS
ISO THUNDER DURING THIS EVENT. LEANED TOWARD THE COOLER GUIDANCE
FOR TEMPS SAT/SAT NIGHT.
EXPECTING THE MAIN BATCH OF RAIN TO SHIFT EAST DURING SUNDAY
MORNING...SO BY NOON...JUST A CHANCE OF A SHOWER/TSTM REMAINS AS THE
TRAILING UPPER TROUGH AXIS APPROACHES. THE THREAT OF RAINFALL LOOKS
TO END SUNDAY EVENING AS THE EXITS MOVES EAST AND THE ATMOSPHERE
STABILIZES.
WEAK HIGH PRESSURE THEN BUILDS IN FOR MONDAY WITH A DRY DAY LIKELY
AND HIGH TEMPS CLOSE TO NORMAL. A COLD FRONT APPROACHES ON TUESDAY
AND IS FORECAST TO PASS THROUGH TUE NIGHT INTO EARLY WED MORNING.
CHANCE SHOWER/TSTM FOCUSED TOWARD THE WESTERN HALF OF THE CWA DURING
THE DAY...WITH BEST CHANCES FOR ALL DURING THE NIGHT.
OUTSIDE OF A POSSIBLE LINGERING SHOWER WEDNESDAY MORNING FOR THE
EASTERN ZONES...WEDNESDAY AND THURSDAY APPEAR TO BE DRY WITH A
RETURN TO WEAK HIGH PRESSURE. HIGHS NEAR NORMAL BOTH DAYS.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
LOW PRESSURE APPROACHES OVERNIGHT AND PASSES TO THE SOUTH FRIDAY
MORNING.
VFR THROUGH THE EVENING...HOWEVER LGT RAIN OR SPRINKLES WILL
IMPACT THE CITY ARPTS. MVFR CONDITIONS ARE POSSIBLE AFTER
MIDNIGHT IN PERIODS OF STEADIER RAIN. AN IMPROVEMENT TO VFR IS
EXPECTED FRIDAY MORNING AFTER THE MORNING PUSH.
S/SW WINDS LIGHTEN THIS EVENING BEFORE TURNING TO THE EAST/NE
LATE TONIGHT. ESE WINDS FROM ABOUT 18Z THRU THE REMAINDER OF THE
TAF PERIOD.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: SOME -RA OR SPRINKLES THRU 3Z BUT VFR VIS
EXPECTED.
KLGA FCSTER COMMENTS: SOME -RA OR SPRINKLES THRU 3Z BUT VFR VIS
EXPECTED.
KEWR FCSTER COMMENTS: SOME -RA OR SPRINKLES THRU 3Z BUT VFR VIS
EXPECTED. WINDS MAY BACK TO AROUND 190 TRUE THRU 3Z.
KTEB FCSTER COMMENTS: SOME -RA OR SPRINKLES THRU 3Z BUT VFR VIS
EXPECTED. WINDS MAY BACK TO AROUND 190 TRUE THRU 3Z.
KHPN FCSTER COMMENTS: SOME -RA OR SPRINKLES THRU 3Z BUT VFR VIS
EXPECTED.
KISP FCSTER COMMENTS: SOME -RA OR SPRINKLES THRU 3Z BUT VFR VIS
EXPECTED.
.OUTLOOK FOR 00Z SATURDAY THROUGH TUESDAY...
.FRIDAY NIGHT-SATURDAY MORNING...VFR.
.SATURDAY AFTERNOON-SATURDAY NIGHT...BECOMING MVFR IN THE
AFTERNOON...THEN IFR OR LOWER AT NIGHT IN RAIN. E-SE WIND
G20-30KT POSSIBLE.
.SUNDAY...CHANCE MVFR OR LOWER IN THE MORNING...THEN VFR. SW
WINDS G20-25KT POSSIBLE IN AFTERNOON.
.SUNDAY NIGHT-TUESDAY...VFR.
&&
.MARINE...
MADE MINOR CHANGES THIS UPDATE TO REFLECT THE LATEST TRENDS IN
OBSERVATIONS AND GUIDANCE. THE FORECAST APPEARS ON TRACK.
EASTERLY FLOW WILL INCREASE ON FRI AS LOW PRESSURE PASSES TO THE
SOUTH. WINDS AND SEAS MAY APPROACH SCA CRITERIA BUT IT WILL BE A
CLOSE CALL...SO NO HEADLINES YET.
A STRONG EASTERLY FLOW WILL DEVELOP SATURDAY INTO SATURDAY NIGHT
WITH THE APPROACH OF LOW PRESSURE FROM THE WEST. ALL WATERS WILL
LIKELY SEE AT LEAST SCA CONDITIONS. FOR THE OCEAN...THERE IS THE
POTENTIAL FOR GALE FORCE WINDS MAINLY SATURDAY AFTERNOON AND
EVENING AS THE PRESSURE GRADIENT TIGHTENS AND A LOW LEVEL JET
PASSES THROUGH. WINDS ARE CURRENTLY FORECAST TO DIMINISH LATE SAT
NIGHT INTO SUNDAY MORNING WITH THE THINKING THAT A WEAK LOW CENTER
PASSES THROUGH THE WATERS BEFORE SHIFTING EAST OF THE WATERS BY
SUNDAY AFTERNOON. WINDS THEN SHIFT SW-W AND PICK UP IN INTENSITY
AGAIN. THE OCEAN WATERS WOULD MORE LIKELY CONTINUE TO HAVE SCA
CONDITIONS THROUGH THE DAY SUNDAY. SEAS COULD TAKE SOME TIME TO
DIMINISH BELOW CRITERIA LEVELS DUE TO A LINGERING SWELL...
POSSIBLY NOT DROPPING BELOW 5 FT UNTIL LATE MONDAY NIGHT.
THEREAFTER...SUB-SCA CONDITIONS ARE FORECAST FOR ALL WATERS.
&&
.HYDROLOGY...
THERE IS THE POTENTIAL FOR 1/10 TO 1/4 INCH OF RAINFALL TONIGHT.
SIGNIFICANT WIDESPREAD RAINFALL IS LIKELY FROM LATE SATURDAY INTO
SUNDAY MORNING. RAINFALL AMOUNTS BETWEEN 1 AND 2 INCHES ARE
FORECAST. LOCALLY HIGHER AMOUNTS ARE POSSIBLE. THIS RAIN IS
EXPECTED TO OCCUR IN A RELATIVELY LONG DURATION SO THE CHANCE FOR
ANY SIGNIFICANT FLOODING IS LOW. HOWEVER...LOCALLY HEAVY RAINFALL
IS POSSIBLE LEADING TO MINOR URBAN AND POOR DRAINAGE
FLOODING...PARTICULARLY LATE IN THE DAY SATURDAY AND SATURDAY
EVENING.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MALOIT/GOODMAN/JC
NEAR TERM...MALOIT/GOODMAN
SHORT TERM...GOODMAN
LONG TERM...JC
AVIATION...JMC/PW
MARINE...MALOIT/GOODMAN/JC
HYDROLOGY...MALOIT/GOODMAN/JC
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
250 PM EDT WED JUN 24 2015
...ISOLD STRONG TO SEVERE STORMS REST OF TODAY...
.SHORT TERM...SO FAR TODAY ONLY ISOLD TO SCT CONVECTION OVER NE FL
SLOWLY MOVING ENEWD. WITH SBCAPE VALUES OF 2000-3000J...HIGH
CONFIDENCE CONVECTION WILL FURTHER INCREASE AND PROPAGATE SLOWLY EWD
GIVEN THE PREVAILING SWLY TO WLY FLOW AT ABOUT 5-10 MPH THROUGH
ABOUT 12 KFT. WET DOWNBURSTS ARE THE PRIMARY THREAT WITH GUSTS OF 50-
60 MPH POSSIBLE. HAVE PAINTED POPS OF 40-60 PERCENT IN NE FL AND 20-
40 PERCENT IN SE GA. FOR TONIGHT...ISOLD TO SCT CONVECTION WILL BE
ONGOING IN THE EVENING WITH BEST COVERAGE IN NE FL. EXPECT
CONVECTION TO WIND DOWN LATER TODAY THOUGH SOME ISOLD CELLS...MAINLY
SHOWERS WILL BE POSSIBLE WELL AFTER MIDNIGHT. MIN TEMPS IN THE LOWER
TO MID 70S EXPECTED.
THURSDAY...LOW LEVEL TROUGH REMAINS ENTRENCHED FROM THE CAROLINAS
SWWD TO CENTRAL AL AND MS. BEST MOISTURE POSITIONED AGAIN OVER NE FL
AND PORTIONS OF SE GA WITH GFS SOUNDING SHOW PWAT OF 2 INCHES.
GUIDANCE INDICATING AN ACTIVE DAY...MORE THAN TODAY. FOR NOW SHOWED
SOLID 60 PERCENT FOR NE FL AND 40-60 IN SE GA. PRIMARY THREATS
REMAIN FREQUENT LIGHTNING AND STRONG DOWNBURST WINDS WITH PULSE
STORMS GIVEN WEAK BULK SHEAR VALUES. HIGHS WILL BE A BIT LOWER THAN
THE PAST FEW DAYS...PREVAILING IN THE LOWER 90S.
UPPER PATTERN TRANSITIONS THURSDAY NIGHT THRU FRIDAY NIGHT FROM
UPPER RIDGE SOUTHERN STATES...ZONAL WESTERLIES NORTHERN STATES...TO
A PATTERN FEATURING A STRONG WESTERN UPR RIDGE...STRONG E-CTRL UPR
TROF BY SAT MORNING. WILL CONTINUE PATTERN OF CHANCE POPS FOR
AFTERNOON/EVENING SHOWERS/T-STORMS THRU FRIDAY EVENING. SLIGHTLY
LOWER HIGH TEMPS EXPECTED FRIDAY WITH LWR 90S INTERIOR...AROUND 90
EASTERN COUNTIES..UPR 80S COAST. LOW TEMPS LWR-MID 70S INLAND...MID-
UPR 70S COAST THURSDAY AND FRIDAY NIGHTS.
.LONG TERM /SATURDAY THRU WEDNESDAY/...
WEEKEND FEATURES STRONG UPR TROF OVER EASTERN STATES WITH SURFACE
COLD FRONT DRIFTING SE OVER SRN GA. ANTICIPATE A DECENT FRONTAL BAND
OF SHOWERS/ FEW T-STORMS OVER SRN GA SAT AFTN/NIGHT...AND ACROSS
ENTIRE FORECAST AREA SUNDAY. TEMPTED TO GO LIKELY POPS THESE
AREAS...BUT CAPPED AT 50 PCT FOR THE MOMENT...LATER SHIFTS MAY
INCREASE POPS FURTHER AS CERTAINTY ON THAT LEVEL OF COVERAGE
INCREASES. HIGH TEMPS SAT AROUND 90 COAST AND SCTRL GA... LWR 90S
ELSEWHERE. FOR SUNDAY...SLIGHTLY LOWER...WITH UPR 80S SRN GA AND
COAST...AROUND 90 INLAND NE FL.
UPPER PATTERN CHANGES VERY LITTLE THROUGH THE MIDDLE OF NEXT WEEK.
FRONTAL MOISTURE BAND SITS OVER NRN FL...WITH DECENT CHANCE POPS
EACH DAY ACROSS NE FL...LESSER CHANCES ACRS SE GA. CONSENSUS MODEL
GUIDANCE SUGGESTS SOME TEMPS EXPECTED TO BE CLOSE TO NORMAL EARLY
NEXT WEEK.
&&
.AVIATION...A FEW TSTMS CAN BE EXPECTED IN AND NEAR THE NE FL TAFS
REST OF TODAY WITH MVFR AND GUSTY WINDS. TEMPO GROUPS ADVERTISED
GENERALLY FROM 19Z-23Z...BUT THESE MAY NEED TO BE EXTENDED FURTHER
INTO THE EVENING BASED ON LATEST HRRR GUIDANCE. HOWEVER...ANTICIPATE
CONVECTION WILL BE ON A DOWNWARD TREND AFTER 01Z/02Z WITH VFR
PREVAILING THEREAFTER.
&&
.MARINE....SURFACE TROUGH REMAINS OVER SC INTO CTRL GA...WHILE
SURFACE HIGH PRESSURE IS CENTERED WELL EAST OF THE WATERS...SETTING
UP A S TO SW FLOW PATTERN OVER THE WATERS DURING THE REMAINDER OF
THE WEEK. NOCTURNAL SW FLOW SURGES MAY LEAD TO WINDS CLOSE TO
EXERCISE CAUTION LEVELS IN THE OFFSHORE COMPONENT EACH NIGHT.
A COLD FRONT APPROACHES FROM THE NW DURING THE WEEKEND...WHICH COULD
ENHANCE SW FLOW OVER THE WATERS THEN.
RIP CURRENTS: LOW RISK THROUGH THURSDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 74 95 74 91 / 30 50 40 50
SSI 77 91 77 88 / 20 40 30 50
JAX 74 92 74 90 / 40 60 40 50
SGJ 75 89 75 89 / 50 60 40 50
GNV 73 91 73 90 / 50 60 40 50
OCF 74 91 73 90 / 40 60 40 50
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
SHASHY/WOLF/WALSH
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
921 AM EDT WED JUN 24 2015
...A FEW STRONG TO SEVERE STORMS POSSIBLE THIS AFTERNOON...
.UPDATE...SFC RIDGE CONTS WELL S OF THE AREA WITH PREVAILING SW
TO W FLOW OVER THE LOCAL REGION. WATER VAPOR AND IR IMAGERY SHOWS
A SLOWLY WEAKENING MCS OVER SRN AL WITH SOME DEBRIS MID LEVEL
CLOUDS OVER PORTIONS OF NE FL AND SE GA. THESE CLOUDS MAY SLOW
HEATING SOMEWHAT BUT SHOULD STILL BE ABLE TO REACH THE LOWER TO
MID 90S TODAY. A MID LEVEL TROUGH ACROSS EXTREME SE GA AND NE FL
WILL SLOWLY SINK SWD AND COMBINE WITH HIGH MOISTURE (PWATS NEAR 2
INCHES) AND SEA BREEZES TO PRODUCE SCT TO NUMEROUS SHOWERS AND
STORMS LATER TODAY. SHORT RANGE GUIDANCE AND VSBY IMAGERY SUGGESTS
LIKELY INITIATION OF CONVECTION FROM THE W COAST SEA BREEZE
BOUNDARY...WHICH WILL MOVE INTO THE I-75 CORRIDOR BY EARLY AFTN.
BEST COVERAGE CONTINUES TO POINT TOWARD NE FL DUE TO BETTER
MOISTURE AND DYNAMICS. A MODIFIED RAP SOUNDING SHOWS SBCAPE OF
ABOUT 2600 J/KG AND LI OF -6 AND DCAPE SUPPORTIVE OF STRONG TO
POSSIBLY SEVERE WET DOWNBURSTS OF 50-60 MPH. WEAK STORM MOTION AND
HIGH CAPE VALUES WILL LEAD TO TORRENTIAL DOWNPOURS WITH LOCAL
FLOODING ISSUES POSSIBLE. SCT EVENING CONVECTION WILL SLOWLY
DISSIPATE LATE TONIGHT.
&&
.AVIATION...VFR PREVAILS THROUGH EARLY AFTN WITH A GOOD CHANCE OF
TSTMS AT GNV BY MID AFTN THEN REST OF TAFS BY MID TO LATE AFTN.
VCTS FOR MOST TAFS LOOKS GOOD AT THIS POINT WITH TEMPO GROUP FOR
GNV 17Z-20Z. MVFR VSBY/CIG WITH STRONG WIND GUSTS LIKELY IN
STRONGER STORMS THIS AFTERNOON.
&&
.MARINE...CURRENT FCST ON TRACK WITH OFFSHORE FLOW TURNING MORE S
AND SE BY LATE AFTN FROM E COAST SEA BREEZE. SEAS OF 3 FT OR LESS
WITH SHOWERS AND STORMS POSSIBLE THIS AFTN. WINDS INCREASE AGAIN
TONIGHT TO NEAR SCEC CONDS OFFSHORE. MAIN CONCERNS CENTERED AROUND
TSTMS ACTIVITY LATER THIS AFTN OVER THE NEARSHORE WATERS. WILL
ADJUST WX FCST A BIT TODAY AND TONIGHT FOR THE MORNING UPDATE.
RIP CURRENTS: LOW RISK THROUGH THU OWING TO LIGHT SWELLS AND
PREVAILING OFFSHORE FLOW.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 96 74 95 74 / 20 20 40 40
SSI 90 77 89 78 / 30 30 40 30
JAX 93 75 90 74 / 50 40 50 40
SGJ 90 75 89 75 / 60 50 50 40
GNV 92 73 89 72 / 60 50 50 40
OCF 91 75 89 73 / 50 50 50 40
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
SHASHY/ALLEN
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
401 PM EDT WED JUN 24 2015
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL PREVAIL MUCH OF THIS WEEK WHILE A TROUGH
OF LOW PRESSURE PERSISTS INLAND. A COLD FRONT WILL STALL TO THE
NORTH LATE WEEK INTO THE WEEKEND BEFORE FINALLY CROSSING THE AREA
SUNDAY. THE FRONT COULD STALL JUST OFFSHORE BEFORE DISSIPATING EARLY
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
THROUGH THIS EVENING...SATELLITE PICTURES INDICATE THAT WE/RE
FINALLY STARTING TO SEE SOME VERTICAL DEVELOPMENT TO THE CUMULUS
CLOUD FIELD...FEEDING OFF THE STEEPENING LAPSE RATES. THERE ARE
VARIOUS MESO-SCALE BOUNDARIES SUCH AS OUTFLOW FROM EARLIER MCS/S AND
THE EVER PRESENT PIEDMONT TROUGH. BUT THEY`RE OUTSIDE THE CWFA...SO
WE NEED TO FOCUS INITIALLY IN OUR AREA ON THE SEA BREEZE INLAND
FROM US-17 AND A FEW POPCORN TYPE CELLS THAT FORM DURING THE MAX
HEATING OF THE DAY. BUT DUE TO THE WARM MID LEVELS THEY STILL
MIGHT HAVE SOME DIFFICULTY IN REACHING ANY APPRECIABLE VERTICAL
GROWTH. HOWEVER THERE IS AN ABUNDANCE OF INSTABILITY...WITH
SBCAPES ARE 4000-5000 J/KG AND LIFTED INDICES AS COLD AS -6 TO
-8C. SO IF BOUNDARY MERGERS GET GOING WE WOULD CERTAINLY SEE AN
INCREASE IN BOTH COVERAGE AND UPDRAFT STRENGTH TO THE CONVECTION.
WITH DCAPES OF 1000-1200 J/KG AND WINDEX VALUES OF 65 KT THIS
WOULD SUPPORT STRONG DOWNBURST WINDS...AIDED BY PRECIP LOADING
WITH PWATS CLOSE TO THE 90TH PERCENTILE FOR LATE JUNE. OTHER
HAZARDS INCLUDE FREQUENT LIGHTNING STRIKES...VERY HEAVY RAINS DUE
TO A STORM MOTION OF ONLY AROUND 5 MPH AND SHOULD ANY TALL STORMS
DEVELOP THERE IS ALSO HAIL RISK. PROBABILITY OF SEVERE WEATHER IS
STILL TOO LOW TO INCLUDE IN THE HAZARDOUS WEATHER OUTLOOK...MOST
NOTABLY DUE TO THE HRRR SHOWING LITTLE IN THE WAY OF SIGNIFICANT
CONVECTIVE DEVELOPMENT/ORGANIZATION. WE/LL MAINTAIN A FORECAST OF
ISOLATED TO SCATTERED COVERAGE...ESPECIALLY INLAND...ALTHOUGH ANY
LOW-END SEVERE POTENTIAL LOOKS TO BE FROM ABOUT 6-9 PM. STORMS
WILL GRADUALLY DWINDLE IN BOTH INTENSITY AND AREAL SCOPE...COMING
TO AN END ENTIRELY 11 PM-MIDNIGHT.
THE HEAT ADVISORY HAS WORKED PERFECTLY WITH MANY SITES HAVING HIT
105-110F...WITH EVEN A FEW LOCATIONS SUCH AS WITHERBEE...GOOSE CREEK
AND SYLVANIA REACHING 111-114F. PROVIDED SHOWERS AND T-STORMS DON/T
ORGANIZE TOO MUCH TO IMPACT THE TEMP CURVE...THE HEAT ADVISORY WILL
CONTINUE THROUGH 7 PM.
FOR THE REST OF TONIGHT...THERE ARE HINTS THAT CONVECTION MIGHT GO
OVERNIGHT...BUT ODDS FAVOR THAT ANY ACTIVITY AFTER MIDNIGHT WOULD
IMPACT THE WATERS OUT NEAR THE GULF STREAM AS NOCTURNAL CINH
INCREASES. CONVECTIVE DEBRIS CLOUDINESS WILL DWINDLE AND
FADE...LEAVING US WITH MOSTLY CLEAR OR PARTLY CLOUDY SKIES. A WARM
SW SYNOPTIC FLOW AND MUCH OF THE AREA NEVER FULLY DECOUPLING WILL
PREVENT TEMPS FROM DROPPING ANY LOWER THAN 73-78 INLAND AND 79-82
ON THE COAST AND IN DOWNTOWN CHARLESTON.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
THURSDAY...A LARGE MID LVL RIDGE OF HIGH PRESSURE WILL PERSIST OVER
THE AREA. AT THE SFC...THE AREA WILL BE POSITIONED ALONG THE WESTERN
PERIPHERY OF ATLANTIC HIGH PRESSURE WHILE A PIEDMONT TROUGH BECOMES
SLIGHTLY MORE PRONOUNCED WITH A LOW PRESSURE SYSTEM TRACKING OVER
THE MID ATLANTIC STATES. DESPITE LARGE SCALE SINKING MOTION
ASSOCIATED WITH HIGH PRESSURE ALOFT...THE PROXIMITY OF THE LOW
PRESSURE TROUGH INLAND AND A STALLING COLD FRONT TO OUR NORTH SHOULD
SUPPORT A SLIGHT CHANCE TO LOW-END CHANCE OF SHOWERS AND
THUNDERSTORMS DURING AFTERNOON/EVENING HOURS. DCAPES IN EXCESS OF
1000 J/KG SUGGEST DAMAGING WIND GUST POTENTIAL WITH A FEW STRONGER
THUNDERSTORMS THAT DEVELOP. HOWEVER...THE THREAT OF WIDESPREAD
SEVERE WEATHER IS NOT EXPECTED.
THE MAIN CONCERN ON THURSDAY WILL BE HEAT/HUMIDITY LEVELS...WHICH
WILL BE DEPENDENT ON HOW MUCH CONVECTIVE ACTIVITY OCCURS BEFORE
TYPICAL PEAK HEATING HOURS. AT THIS TIME...HIGH TEMPS ARE FORECAST
TO REACH THE MID/UPPER 90S...WARMEST INLAND. HOWEVER...STRONG
HEATING SHOULD MIX OUT SFC DEWPTS TO AROUND 70 INLAND...WHILE DEWPTS
REMAIN IN THE MID 70S NEAR/BEHIND AN INLAND MOVING SEABREEZE. THESE
TEMPS AND MOISTURE LEVELS SHOULD SUPPORT HEAT INDEX VALUES NEAR 105
DEGREES FOR A FEW HOURS THURSDAY AFTERNOON AND A HEAT ADVISORY COULD
EVENTUALLY BE NEEDED. HOWEVER...SHOULD CLOUD COVER OR PRECIP SHIFT
OVER THE AREA EARLY...HEAT INDEX VALUES WILL LIKELY FALL JUST SHORT
OF ADVISORY LEVELS. OVERNIGHT LOWS WILL REMAIN MILD...IN THE
MID/UPPER 70S INLAND TO LOWER 80S ALONG THE COAST.
FRIDAY AND SATURDAY...MODELS INDICATE LOWERING 500 MB HEIGHTS OVER
THE AREA THIS WEEKEND AS THE MID LVL RIDGE OF HIGH PRESSURE WEAKENS
IN RESPONSE TO A TROUGH OF LOW PRESSURE DIGGING OVER THE
MIDWEST/GREAT LAKES REGION. MOISTURE LEVELS ARE EXPECTED TO INCREASE
AHEAD OF THE APPROACHING TROUGH...WITH PWATS PROJECTED TO BE NEAR
2.0 INCHES OVER THE SOUTHEASTERN UNITED STATES. THESE MOISTURE
LEVELS ALONG WITH INCREASED FORCING FROM A SFC LOW THAT DEVELOPS
ALONG A STALLED FRONT TO OUR NORTH...WILL LIKELY RESULT IN AT LEAST
CHANCES OF SHOWERS/THUNDERSTORMS ON FRIDAY. BY SATURDAY...GREATER
FORCING AND SHEAR WILL LIKELY ARRIVE AS STRONGER WIND FIELDS ROUND
THE SOUTHERN PERIPHERY OF THE MID/UPPER LOW CENTERED OVER THE GREAT
LAKES REGION. SHOWERS AND THUNDERSTORMS WILL LIKELY OCCUR SATURDAY
AFTERNOON...WITH SOME STRONGER THUNDERSTORMS POSSIBLE AHEAD OF A SFC
COLD FRONT MAKING WAY INTO THE SOUTHEASTERN UNITED STATES. DAMAGING
WIND GUSTS APPEAR TO BE THE MAIN THREAT WITH STRONGER THUNDERSTORMS
ON SATURDAY. GIVEN THE AMPLE MOISTURE...SOME THUNDERSTORMS COULD
ALSO PRODUCE HEAVY RAINFALL.
TEMPS ARE EXPECTED TO BE SLIGHTLY COOLER OVER THE WEEKEND...WITH MAX
TEMPS IN THE LOW/MID 90S ON FRIDAY...THEN LOW 90S ON SATURDAY DUE TO
AN INCREASE IN CONVECTIVE COVERAGE. GIVEN THE COOLING TREND...HEAT
ADVISORIES WILL LIKELY NO LONGER BE NEEDED THIS WEEKEND. OVERNIGHT
LOWS SHOULD REMAIN IN THE MID/UPPER 70S.&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
BROAD UPPER TROUGH WILL ENCOMPASS THE EASTERN U.S. THROUGH THE LONG
TERM PERIOD. A POTENT SHORTWAVE WILL SEND AN AREA OF LOW PRESSURE
AND ATTENDANT FRONT THROUGH THE FORECAST AREA ON SUNDAY. GIVEN
FORCING FROM UPPER JET...SHORTWAVE ENERGY AND COLD FRONT...IT SHOULD
BE A PRETTY ACTIVE DAY ESPECIALLY GIVEN DECENT SHEAR AND DEEP
MOISTURE. THE FRONT WILL LIKELY PUSH OFF THE COAST EARLY
MONDAY...AND REMAIN STATIONARY OFFSHORE BEFORE DISSIPATING TUESDAY.
WEAK HIGH PRESSURE IS EXPECTED TO PREVAIL BY MID WEEK. TEMPERATURES
WILL BE AT OR BELOW CLIMO THROUGH THE PERIOD.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
VFR THROUGH 18Z THURSDAY.
ISOLATED SHRA/TSRA WILL CONTINUE TO DEVELOP IN THE VICINITY OF
KCHS THROUGH 01Z...AND WE WILL AMEND AS NECESSARY SHOULD ANYTHING
LOOK TO MORE DIRECTLY AFFECT THE AIRFIELD.
WHILE WE CAN/T RULE OUT A TSRA IMPACTING KSAV FROM ABOUT
21-01Z...PROBABILITIES ARE STILL TOO LOW TO INCLUDE WITH THE
LATEST TAF SET.
EXTENDED AVIATION OUTLOOK...FLIGHT RESTRICTIONS ARE POSSIBLE IN
AFTERNOON SHOWERS/THUNDERSTORMS...ESPECIALLY LATE THIS WEEKEND.
&&
.MARINE...
TONIGHT...IT/S STATUS QUO IN REGARDS TO THE SYNOPTIC PATTERN AND
RESULTING CONDITIONS ACROSS THE COASTAL WATERS...WITH SUB-TROPICAL
RIDGING TO THE SOUTH/SE...MESO-HIGH PRESSURE IN THE NE GULF OF
MEXICO AND A NE-SW ALIGNED TROUGH INLAND. ADEQUATE MIXING OF 20-25
KT GEOSTROPHIC WINDS AND A MODEST GRADIENT WILL ALLOW FOR SOUTH/SW
WINDS UP TO 15 OR 20 KT WITH OCCASIONAL HIGHER GUSTS. WAVES OF 1-2
FT WILL BE COMMON IN CHARLESTON HARBOR...WITH 2-4 FT IN THE OPEN
ATLANTIC...HIGHEST ON AMZ350-374.
THURSDAY THROUGH MONDAY...ATLANTIC HIGH PRESSURE WILL DOMINATE THE
COASTAL WATERS WHILE A TROUGH OF LOW PRESSURE PERSISTS INLAND
THROUGH LATE WEEK. A COLD FRONT IS EXPECTED TO SHIFT OVER THE WATERS
LATE WEEKEND...BEFORE EVENTUALLY STALLING/DISSIPATING EARLY NEXT
WEEK. A TIGHTENED PRESSURE GRADIENT WILL KEEP WINDS FAIRLY ELEVATED
THROUGH THE PERIOD. NOCTURNAL JETTING AND AFTERNOON SEA BREEZE
CIRCULATIONS WILL RESULT IN SOUTH/SOUTHWEST WINDS PEAKING AROUND 15-
20 KTS AT TIMES...ESPECIALLY ACROSS THE CHARLESTON COUNTY COASTAL
WATERS. WIND GUSTS COULD REACH SMALL CRAFT ADVISORY CRITERIA
SATURDAY AFTERNOON OR NIGHT...THEN SLOWLY IMPROVE EARLY NEXT WEE,
SEAS WILL MAINLY BE 2-4 FEET...BUT COULD REACH 6 FEET IN THE OUTER
PORTIONS OF THE WATERS THIS WEEKEND.
&&
.CLIMATE...
RECORD HIGH MINIMUMS FOR JUNE 24TH...
KCHS...79 SET IN 1998.
KCXM...85 SET IN 1998.
KSAV...80 SET IN 1914.
RECORD HIGH MINIMUMS FOR JUNE 25TH...
KCHS...79 SET IN 2010.
KCXM...83 SET IN 1998.
KSAV...80 SET IN 1914.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR GAZ087-088-
099>101-114>119-137>141.
SC...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR SCZ040-042>045-
047>052.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...
CLIMATE...
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
138 PM EDT WED JUN 24 2015
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL PREVAIL MUCH OF THIS WEEK WHILE A TROUGH
OF LOW PRESSURE PERSISTS INLAND. A COLD FRONT WILL STALL TO THE NORTH
LATE WEEK INTO THE WEEKEND BEFORE FINALLY CROSSING THE AREA LATE
SUNDAY. THE FRONT MAY STALL JUST OFFSHORE BEFORE DISSIPATING EARLY
NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
FOR THE AFTERNOON UPDATE WE HAVE MADE MINOR CHANGES TO HOURLY/MAX
TEMPS...POPS AND SKY COVER...BUT NOTHING MAJOR. CONVECTION HAS
BEEN SLOW IN DEVELOPING...WITH ONLY FEW-SCATTERED CUMULUS
FORMATION. WE/LL SOON HIT OUR CONVECTIVE TEMP IN THE MID 90S...SO
THE GENERAL TREND OF THE FORECAST IS STILL ON TRACK.
AFTER OUR BRIEF RESPITE FROM THE EXTREME HEAT AND HUMIDITY
COMBINATION YESTERDAY...IT/S BACK TO THE OPPRESSIVE AND STICKY
CONDITIONS THAT WE HAVE SEEN MUCH OF THE PAST 2 WEEKS. TEMPS ARE
RUNNING ON AVERAGE ABOUT 2-3F WARMER THAN 24 HOURS AGO...AND WITH
850 MB TEMPS OF 19-20C AND PLENTY OF INSOLATION...WE/RE ON OUR WAY
TO THE MID AND UPPER 90S INLAND FROM US-17. A FEW SPOTS MIGHT EVEN
PEAK AT THE CENTURY MARK. DEW POINTS WILL MIX OUT A BIT
INLAND...BUT WILL POOL BEHIND THE SEA BREEZE...WHICH SUPPORTS MOST
HEAT INDICES AS HIGH AS 105-109F...BUT A FEW SPOTS OF THE COASTAL
CORRIDOR WILL MAX OUT AT 110-114F AROUND THE TIME OF THE SEA
BREEZE PASSAGE. OUR HEAT ADVISORY WILL OBVIOUSLY REMAIN ACTIVE.
THE FORECAST FOR HOW CONVECTION WILL PAN OUT IS FAR FROM CERTAIN
GIVEN A WIDE DISPARITY IN VARIOUS MODELS. WE STILL HAVE A SUBTLE
WEAKNESS IN THE RIDGING ALOFT...BUT THAT LOOKS TO BE JUST OFF THE
COAST. THERE WILL BE VARIOUS MESO-SCALE BOUNDARIES SUCH AS
OUTFLOW FROM EARLIER MCS THAT MOVED OFF THE MID-ATLANTIC AND
ANOTHER FROM ALABAMA. THERE IS ALSO THE EVER PRESENT PIEDMONT
TROUGH AND THE SEA BREEZE BOUNDARY. THESE FACTORS SHOULD PROVIDE
THE NECESSARY INITIATION...BUT THERE IS STILL A STRONG 3-5C CAP
AND UNFAVORABLE MID LEVEL LAPSE RATES WITH WARM 500 MB
TEMPS...IMPLYING THAT STORMS MAY HAVE A DIFFICULT TIME IN
ATTAINING MUCH VERTICAL GROWTH. ON THE FAVORABLE SIDE OUR LOW
LEVEL LAPSE RATES ARE FAVORABLE AND THERE IS PLENTY OF INSTABILITY
WITH SBCAPES FORECAST TO REACH 4000-4500 J/KG AND LIFTED INDEX OF
-6 TO -8C. LOOK FOR CONVECTION TO GET GOING AROUND 3-4 PM AS WE
HIT OUR CONVECTIVE TEMP IN THE MID 90S.
FOR THE MOMENT A PULSE TYPE ENVIRONMENT SEEMS A MORE LIKELY
CONVECTIVE MODE RATHER THAN MULTI-CELLULAR...BUT IF BOUNDARY
INTERACTIONS AND MERGERS TAKE PLACE THAT COULD CHANGE. WE/LL
MAINTAIN A PROBABILITY FORECAST OF 20-30 PERCENT...HIGHEST INLAND
AND MAINTAIN A CLOSE WATCH ON MESO-SCALE TRENDS TO SEE IF WE NEED
TO RAISE POPS.
DCAPES OF 1000-1200 J/KG AND WINDEX VALUES OF 65 KT WOULD SUPPORT
STRONG DOWNBURST WINDS...AIDED BY PRECIP LOADING WITH PWATS CLOSE
TO THE 90TH PERCENTILE FOR LATE JUNE. OTHER HAZARDS INCLUDE
FREQUENT LIGHTNING STRIKES...VERY HEAVY RAINS DUE TO A STORM
MOTION OF ONLY AROUND 5 MPH AND SHOULD ANY TALL STORMS DEVELOP
THERE IS ALSO HAIL RISK. PROBABILITY OF SEVERE WEATHER IS STILL
TOO LOW TO INCLUDE IN THE HAZARDOUS WEATHER OUTLOOK...MOST NOTABLY
DUE TO THE HRRR SHOWING LITTLE IN THE WAY OF CONVECTIVE
ORGANIZATION.
CONDITIONS SHOULD BE MAINLY QUIET TONIGHT WITH PARTLY CLOUDY SKIES
AND LOWS A BIT WARMER THAN WEDNESDAY MORNING...ESPECIALLY IF TSTMS
COVERAGE IS LOWER END TODAY.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
THURSDAY...PERSISTENT MID LEVEL RIDGE WILL HOLD FAIRLY STRONG FOR
ONE MORE DAY...ALTHOUGH SUBTLE WEAKENING WILL BEGIN TO OCCUR. THE
SURFACE PATTERN WILL CONTINUE TO BE FAIRLY STATIC AS THE AREA
REMAINS ON THE WESTERN PERIPHERY OF ATLANTIC HIGH PRESSURE WITH A
PIEDMONT TROUGH SITUATED INLAND. HIGH TEMPERATURES IN THE MID/UPPER
90S AWAY FROM THE COAST WILL COMBINE WITH MODERATE HUMIDITY LEVELS
TO PRODUCE HEAT INDICES OF 105-108 IN THE AFTERNOON. THUS A HEAT
ADVISORY WILL LIKELY BE NEEDED. LARGE SCALE FORCING WILL LARGELY BE
MISSING HOWEVER CONVECTION WILL DEVELOP AS A RESULT OF SEA BREEZE
AND/OR CONVERGENCE ALONG SURFACE TROUGH. FORECAST SURFACE BASED
CAPE NEAR 3000 J/KG MAY SUPPORT A FEW STRONGER POSSIBLY SEVERE
STORMS...WITH GUSTY WINDS THE PRIMARY THREAT GIVEN DCAPE VALUES IN
EXCESS OF 1000 J/KG. THURSDAY NIGHT...SURFACE LOW PRESSURE WILL
CROSS THE MID-ATLANTIC STATES ABSORBING THE PIEDMONT TROUGH. AN
ATTENDANT FRONT WILL STALL NORTH OF THE AREA. LOWS WILL BE QUITE
MILD RANGING FROM THE MID 70S INLAND TO AROUND 80 ALONG THE COAST.
FRIDAY...AN AREA OF LOW PRESSURE WILL DEVELOP OVER THE CAROLINAS
ALONG THE AFOREMENTIONED STALLED FRONT. DEEP MOISTURE AND PROXIMITY
TO BOUNDARY WILL ALLOW FOR HIGHER COVERAGE OF SHOWERS AND
THUNDERSTORMS. FORECAST CURRENTLY FEATURES HIGH CHANCE POPS OVER
MUCH OF THE AREA DURING PEAK HEATING HOURS. A FEW STRONGER STORMS
WILL BE POSSIBLE ESPECIALLY IN THE NORTHERN ZONES WHERE INSTABILITY
AND MID LEVEL ENVIRONMENT IS MORE FAVORABLE...WITH GUSTY WINDS
PRIMARY THREAT. FORECAST HEAT INDICES MAY BRIEFLY REACH THE LOCAL
HEAT ADVISORY CRITERIA OF 105 IN THE AFTERNOON WITH HIGH
TEMPERATURES IN THE LOW/MID 90S...HOWEVER DURATION AND AREAL EXTENT
WILL BE MARGINAL AT BEST AND GIVEN EXPECTED CONVECTION...THINK A
HEAT ADVISORY WILL LIKELY NOT BE NEEDED. CONVECTION MAY LINGER INTO
THE OVERNIGHT PERIOD...WITH FOCUS SHIFTING MORE TO THE COASTAL
WATERS. LOWS WILL AGAIN BE IN THE MID TO UPPER 70S.
SATURDAY...THE UPPER LEVEL PATTERN WILL BECOME MUCH MORE AMPLIFIED
AS DEEPENING TROUGH AND ASSOCIATED VORT MAX DIGS INTO THE GREAT
LAKES REGION. THIS WILL HELP SEND ANOTHER AREA OF LOW PRESSURE
TOWARDS EAST COAST WHICH WILL EVENTUALLY ENGULF THE STATIONARY
FRONT/LOW. BETTER UPPER SUPPORT...DEEP MOISTURE AND VARIOUS SURFACE
BOUNDARIES WILL ALLOW FOR A FAIRLY ACTIVE DAY WITH STRONGER STORMS
POSSIBLE GIVEN DECENT SHEAR AND FORECAST INSTABILITY. HIGH
TEMPERATURES WILL MAINLY BE IN THE LOW 90S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
BROAD UPPER TROUGH WILL ENCOMPASS THE EASTERN U.S. THROUGH THE LONG
TERM PERIOD. A POTENT SHORTWAVE WILL SEND AN AREA OF LOW PRESSURE
AND ATTENDANT FRONT THROUGH THE FORECAST AREA ON SUNDAY. GIVEN
FORCING FROM UPPER JET...SHORTWAVE ENERGY AND COLD FRONT...IT SHOULD
BE A PRETTY ACTIVE DAY ESPECIALLY GIVEN DECENT SHEAR AND DEEP
MOISTURE. THE FRONT WILL LIKELY PUSH OFF THE COAST EARLY
MONDAY...AND REMAIN STATIONARY OFFSHORE BEFORE DISSIPATING TUESDAY.
WEAK HIGH PRESSURE IS EXPECTED TO PREVAIL BY MID WEEK. TEMPERATURES
WILL BE AT OR BELOW CLIMO THROUGH THE PERIOD.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
VFR THROUGH 18Z THURSDAY. WHILE WE CAN/T RULE OUT A TSRA IMPACTING
EITHER TERMINAL FROM ABOUT 20Z-01Z...PROBABILITIES ARE STILL TOO
LOW TO INCLUDE WITH THE LATEST TAF SET.
EXTENDED AVIATION OUTLOOK...BRIEF FLIGHT RESTRICTIONS POSSIBLE IN
AFTERNOON SHOWERS/THUNDERSTORMS...ESPECIALLY THIS WEEKEND.
&&
.MARINE...
THE COASTAL WATERS SYNOPTIC PATTERN IS NOT CHANGING MUCH AND
MARINERS FAMILIAR WITH THE SUMMER PATTERNS WILL NOT GET ANY BIG
SURPRISES THROUGH TONIGHT. SOUTH/SW SEA BREEZE CIRCULATIONS THIS
AFTERNOON AND SW NOCTURNAL SURGES WILL PUSH SPEEDS INTO THE 15-20
KT RANGE WITH SOME HIGHER GUSTS AT FAVORED AREAS SUCH AS THE
CHARLESTON LAND/SEA INTERFACE. SEAS WILL BE 2-4 FT ON
AVERAGE...HIGHEST WELL OFFSHORE. WAVES IN THE HARBOR WILL BE 1 TO
2 FT THROUGH THIS EVENING.
THURSDAY THROUGH MONDAY...ATLANTIC HIGH PRESSURE WILL PREVAIL OVER
THE COASTAL WATERS WHILE A TROUGH OF LOW PRESSURE PERSISTS INLAND
THROUGH THE REMAINDER OF THE WEEK. A COLD FRONT IS EXPECTED TO
APPROACH THE WATERS OVER THE WEEKEND AND EVENTUALLY STALL AND
DISSIPATE EARLY NEXT WEEK. TIGHTENED PRESSURE GRADIENT WILL KEEP
WINDS FAIRLY ELEVATED THROUGH THE PERIOD. NOCTURNAL JETTING AND
AFTERNOON SEA BREEZE CIRCULATIONS WILL RESULT IN SOUTH/SOUTHWEST
WINDS PEAKING AROUND 15-20 KT...ESPECIALLY ACROSS THE CHARLESTON
COUNTY COASTAL WATERS. GUSTS MAY REACH NEAR SMALL CRAFT ADVISORY
CRITERIA OF 25 KT AT TIMES...AND HEADLINES MAY NEED TO BE
CONSIDERED. SEAS WILL MAINLY BE 2-4 FEET...BUT MAY REACH 5-6 FEET IN
THE OUTER PORTIONS OF THE WATERS DURING SURGES.
&&
.CLIMATE...
RECORD HIGH MINIMUMS FOR JUNE 24TH...
KCHS...79 SET IN 1998.
KCXM...85 SET IN 1998.
KSAV...80 SET IN 1914.
RECORD HIGH MINIMUMS FOR JUNE 25TH...
KCHS...79 SET IN 2010.
KCXM...83 SET IN 1998.
KSAV...80 SET IN 1914.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR GAZ087-088-
099>101-114>119-137>141.
SC...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR SCZ040-042>045-
047>052.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...ECT
LONG TERM...ECT
AVIATION...
MARINE...
CLIMATE...
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1139 AM EDT WED JUN 24 2015
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL PREVAIL MUCH OF THIS WEEK WHILE A TROUGH
OF LOW PRESSURE PERSISTS INLAND. A COLD FRONT WILL STALL TO THE NORTH
LATE WEEK INTO THE WEEKEND BEFORE FINALLY CROSSING THE AREA LATE
SUNDAY. THE FRONT MAY STALL JUST OFFSHORE BEFORE DISSIPATING EARLY
NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
FOR THE MIDDAY UPDATE WE HAVE MADE MINOR CHANGES TO HOURLY
TEMPS...POPS AND SKY COVER...BUT NOTHING MAJOR. SATELLITE IMAGES
AND SURFACE ANALYSIS SHOWING AN OUTFLOW BOUNDARY FROM THE PREVIOUS
MCS MOVING SOUTHWARD FROM FAR SE NC THROUGH THE PEE-DEE AND
UPSTATE OF SC INTO NORTHERN GA. THIS IS WHERE CONVECTION WILL
LIKELY START POPPING FIRST.
AFTER OUR BRIEF RESPITE FROM THE EXTREME HEAT AND HUMIDITY
COMBINATION YESTERDAY...IT/S BACK TO THE OPPRESSIVE AND STICKY
CONDITIONS THAT WE HAVE SEEN MUCH OF THE PAST 2 WEEKS. TEMPS ARE
RUNNING ON AVERAGE ABOUT 2-3F WARMER THAN 24 HOURS AGO...AND WITH
850 MB TEMPS OF 19-20C AND PLENTY OF INSOLATION...WE/RE ON OUR WAY
TO THE MID AND UPPER 90S INLAND FROM US-17. A FEW SPOTS MIGHT EVEN
PEAK AT THE CENTURY MARK. DEW POINTS WILL MIX OUT A BIT
INLAND...BUT WILL POOL BEHIND THE SEA BREEZE...WHICH SUPPORTS MOST
HEAT INDICES AS HIGH AS 105-109F...BUT A FEW SPOTS OF THE COASTAL
CORRIDOR WILL MAX OUT AT 110-112F AROUND THE TIME OF THE SEA
BREEZE PASSAGE. OUR HEAT ADVISORY WILL OBVIOUSLY REMAIN ACTIVE.
THE FORECAST FOR HOW CONVECTION WILL PAN OUT IS FAR FROM CERTAIN
GIVEN A WIDE DISPARITY IN VARIOUS MODELS. WE STILL HAVE A SUBTLE
WEAKNESS IN THE RIDGING ALOFT...BUT THAT LOOKS TO BE JUST OFF THE
COAST. THERE WILL BE VARIOUS MESO-SCALE BOUNDARIES SUCH S OUTFLOW
FROM EARLIER MCS THAT MOVED OFF THE MID-ATLANTIC AND ANOTHER FROM
ALABAMA. THERE IS ALSO THE EVER PRESENT PIEDMONT TROUGH AND THE
SEA BREEZE BOUNDARY. THESE FACTORS SHOULD PROVIDE THE NECESSARY
INITIATION...BUT THERE IS STILL A STRONG 3-5C CAP AND UNFAVORABLE
MID LEVEL LAPSE RATES WITH WARM 500 MB TEMPS...IMPLYING THAT
STORMS MAY HAVE A DIFFICULT TIME IN ATTAINING MUCH VERTICAL
GROWTH. ON THE FAVORABLE SIDE OUR LOW LEVEL LAPSE RATES ARE
FAVORABLE AND THERE IS PLENTY OF INSTABILITY WITH SBCAPES FORECAST
TO REACH 4000-4500 J/KG AND LIFTED INDEX OF -6 TO -8C. LOOK FOR
CONVECTION TO GET GOING AROUND 1-2 PM AS WE HIT OUR CONVECTIVE
TEMP IN THE MID 90S.
FOR THE MOMENT A PULSE TYPE ENVIRONMENT SEEMS A MORE LIKELY
CONVECTIVE MODE RATHER THAN MULTI-CELLULAR...BUT IF BOUNDARY
INTERACTIONS AND MERGERS TAKE PLACE THAT COULD CHANGE. WE/LL
MAINTAIN A PROBABILITY FORECAST OF 20-30 PERCENT...HIGHEST INLAND
AND MAINTAIN A CLOSE WATCH ON MESO-SCALE TRENDS TO SEE IF WE NEED
TO RAISE POPS.
DCAPES OF 1000-1200 J/KG AND WINDEX VALUES OF 65 KT WOULD SUPPORT
STRONG DOWNBURST WINDS...AIDED BY PRECIP LOADING WITH PWATS CLOSE
TO THE 90TH PERCENTILE FOR LATE JUNE. OTHER HAZARDS INCLUDE
FREQUENT LIGHTNING STRIKES...VERY HEAVY RAINS DUE TO A STORM
MOTION OF ONLY AROUND 5 MPH AND SHOULD ANY TALL STORMS DEVELOP
THERE IS ALSO HAIL RISK. PROBABILITY OF SEVERE WEATHER IS STILL
TOO LOW TO INCLUDE IN THE HAZARDOUS WEATHER OUTLOOK...MOST NOTABLY
DUE TO THE HRRR SHOWING LITTLE IN THE WAY OF CONVECTIVE
ORGANIZATION.
CONDITIONS SHOULD BE MAINLY QUIET TONIGHT WITH PARTLY CLOUDY SKIES
AND LOWS A BIT WARMER THAN WEDNESDAY MORNING...ESPECIALLY IF TSTMS
COVERAGE IS LOWER END TODAY.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
THURSDAY...PERSISTENT MID LEVEL RIDGE WILL HOLD FAIRLY STRONG FOR
ONE MORE DAY...ALTHOUGH SUBTLE WEAKENING WILL BEGIN TO OCCUR. THE
SURFACE PATTERN WILL CONTINUE TO BE FAIRLY STATIC AS THE AREA
REMAINS ON THE WESTERN PERIPHERY OF ATLANTIC HIGH PRESSURE WITH A
PIEDMONT TROUGH SITUATED INLAND. HIGH TEMPERATURES IN THE MID/UPPER
90S AWAY FROM THE COAST WILL COMBINE WITH MODERATE HUMIDITY LEVELS
TO PRODUCE HEAT INDICES OF 105-108 IN THE AFTERNOON. THUS A HEAT
ADVISORY WILL LIKELY BE NEEDED. LARGE SCALE FORCING WILL LARGELY BE
MISSING HOWEVER CONVECTION WILL DEVELOP AS A RESULT OF SEA BREEZE
AND/OR CONVERGENCE ALONG SURFACE TROUGH. FORECAST SURFACE BASED
CAPE NEAR 3000 J/KG MAY SUPPORT A FEW STRONGER POSSIBLY SEVERE
STORMS...WITH GUSTY WINDS THE PRIMARY THREAT GIVEN DCAPE VALUES IN
EXCESS OF 1000 J/KG. THURSDAY NIGHT...SURFACE LOW PRESSURE WILL
CROSS THE MID-ATLANTIC STATES ABSORBING THE PIEDMONT TROUGH. AN
ATTENDANT FRONT WILL STALL NORTH OF THE AREA. LOWS WILL BE QUITE
MILD RANGING FROM THE MID 70S INLAND TO AROUND 80 ALONG THE COAST.
FRIDAY...AN AREA OF LOW PRESSURE WILL DEVELOP OVER THE CAROLINAS
ALONG THE AFOREMENTIONED STALLED FRONT. DEEP MOISTURE AND PROXIMITY
TO BOUNDARY WILL ALLOW FOR HIGHER COVERAGE OF SHOWERS AND
THUNDERSTORMS. FORECAST CURRENTLY FEATURES HIGH CHANCE POPS OVER
MUCH OF THE AREA DURING PEAK HEATING HOURS. A FEW STRONGER STORMS
WILL BE POSSIBLE ESPECIALLY IN THE NORTHERN ZONES WHERE INSTABILITY
AND MID LEVEL ENVIRONMENT IS MORE FAVORABLE...WITH GUSTY WINDS
PRIMARY THREAT. FORECAST HEAT INDICES MAY BRIEFLY REACH THE LOCAL
HEAT ADVISORY CRITERIA OF 105 IN THE AFTERNOON WITH HIGH
TEMPERATURES IN THE LOW/MID 90S...HOWEVER DURATION AND AREAL EXTENT
WILL BE MARGINAL AT BEST AND GIVEN EXPECTED CONVECTION...THINK A
HEAT ADVISORY WILL LIKELY NOT BE NEEDED. CONVECTION MAY LINGER INTO
THE OVERNIGHT PERIOD...WITH FOCUS SHIFTING MORE TO THE COASTAL
WATERS. LOWS WILL AGAIN BE IN THE MID TO UPPER 70S.
SATURDAY...THE UPPER LEVEL PATTERN WILL BECOME MUCH MORE AMPLIFIED
AS DEEPENING TROUGH AND ASSOCIATED VORT MAX DIGS INTO THE GREAT
LAKES REGION. THIS WILL HELP SEND ANOTHER AREA OF LOW PRESSURE
TOWARDS EAST COAST WHICH WILL EVENTUALLY ENGULF THE STATIONARY
FRONT/LOW. BETTER UPPER SUPPORT...DEEP MOISTURE AND VARIOUS SURFACE
BOUNDARIES WILL ALLOW FOR A FAIRLY ACTIVE DAY WITH STRONGER STORMS
POSSIBLE GIVEN DECENT SHEAR AND FORECAST INSTABILITY. HIGH
TEMPERATURES WILL MAINLY BE IN THE LOW 90S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
BROAD UPPER TROUGH WILL ENCOMPASS THE EASTERN U.S. THROUGH THE LONG
TERM PERIOD. A POTENT SHORTWAVE WILL SEND AN AREA OF LOW PRESSURE
AND ATTENDANT FRONT THROUGH THE FORECAST AREA ON SUNDAY. GIVEN
FORCING FROM UPPER JET...SHORTWAVE ENERGY AND COLD FRONT...IT SHOULD
BE A PRETTY ACTIVE DAY ESPECIALLY GIVEN DECENT SHEAR AND DEEP
MOISTURE. THE FRONT WILL LIKELY PUSH OFF THE COAST EARLY
MONDAY...AND REMAIN STATIONARY OFFSHORE BEFORE DISSIPATING TUESDAY.
WEAK HIGH PRESSURE IS EXPECTED TO PREVAIL BY MID WEEK. TEMPERATURES
WILL BE AT OR BELOW CLIMO THROUGH THE PERIOD.
&&
.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
VFR THROUGH 12Z THURSDAY. POTENTIAL FOR AFTERNOON AND EVENING
SHOWERS AND TSTMS TODAY IS TOO LOW FOR ANY MENTIONS IN THE CURRENT
TAF CYCLE AT THIS TIME...ESPECIALLY WITH UNCERTAINTIES WITH
TIMING AND COVERAGE.
EXTENDED AVIATION OUTLOOK...BRIEF FLIGHT RESTRICTIONS POSSIBLE IN
AFTERNOON SHOWERS/THUNDERSTORMS...ESPECIALLY THIS WEEKEND.
&&
.MARINE...
THE COASTAL WATERS SYNOPTIC PATTERN IS NOT CHANGING MUCH AND
MARINERS FAMILIAR WITH THE SUMMER PATTERNS WILL NOT GET ANY BIG
SURPRISES THROUGH TONIGHT. SOUTH/SW SEA BREEZE CIRCULATIONS THIS
AFTERNOON AND SW NOCTURNAL SURGES WILL PUSH SPEEDS INTO THE 15-20
KT RANGE WITH SOME HIGHER GUSTS AT FAVORED AREAS SUCH AS THE
CHARLESTON LAND/SEA INTERFACE. SEAS WILL BE 2-4 FT ON
AVERAGE...HIGHEST WELL OFFSHORE. WAVES IN THE HARBOR WILL BE 1 TO
2 FT THROUGH THIS EVENING.
THURSDAY THROUGH MONDAY...ATLANTIC HIGH PRESSURE WILL PREVAIL OVER
THE COASTAL WATERS WHILE A TROUGH OF LOW PRESSURE PERSISTS INLAND
THROUGH THE REMAINDER OF THE WEEK. A COLD FRONT IS EXPECTED TO
APPROACH THE WATERS OVER THE WEEKEND AND EVENTUALLY STALL AND
DISSIPATE EARLY NEXT WEEK. TIGHTENED PRESSURE GRADIENT WILL KEEP
WINDS FAIRLY ELEVATED THROUGH THE PERIOD. NOCTURNAL JETTING AND
AFTERNOON SEA BREEZE CIRCULATIONS WILL RESULT IN SOUTH/SOUTHWEST
WINDS PEAKING AROUND 15-20 KT...ESPECIALLY ACROSS THE CHARLESTON
COUNTY COASTAL WATERS. GUSTS MAY REACH NEAR SMALL CRAFT ADVISORY
CRITERIA OF 25 KT AT TIMES...AND HEADLINES MAY NEED TO BE
CONSIDERED. SEAS WILL MAINLY BE 2-4 FEET...BUT MAY REACH 5-6 FEET IN
THE OUTER PORTIONS OF THE WATERS DURING SURGES.
&&
.CLIMATE...
RECORD HIGH MINIMUMS FOR JUNE 24TH...
KCHS...79 SET IN 1998.
KCXM...85 SET IN 1998.
KSAV...80 SET IN 1914.
RECORD HIGH MINIMUMS FOR JUNE 25TH...
KCHS...79 SET IN 2010.
KCXM...83 SET IN 1998.
KSAV...80 SET IN 1914.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR GAZ087-088-
099>101-114>119-137>141.
SC...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR SCZ040-042>045-
047>052.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...ECT
LONG TERM...ECT
AVIATION...
MARINE...
CLIMATE...
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1022 AM EDT WED JUN 24 2015
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL PREVAIL MUCH OF THIS WEEK WHILE A TROUGH
OF LOW PRESSURE PERSISTS INLAND. A COLD FRONT WILL STALL TO THE NORTH
LATE WEEK INTO THE WEEKEND BEFORE FINALLY CROSSING THE AREA LATE
SUNDAY. THE FRONT MAY STALL JUST OFFSHORE BEFORE DISSIPATING EARLY
NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AFTER OUR BRIEF RESPITE FROM THE EXTREME HEAT AND HUMIDITY
COMBINATION YESTERDAY...IT/S BACK TO THE OPPRESSIVE AND STICKY
CONDITIONS THAT WE HAVE SEEN MUCH OF THE PAST 2 WEEKS. TEMPS ARE
RUNNING ON AVERAGE ABOUT 2-3F WARMER THAN 24 HOURS AGO...AND WITH
850 MB TEMPS OF 19-20C AND PLENTY OF INSOLATION...WE/RE ON OUR WAY
TO THE MID AND UPPER 90S INLAND FROM US-17. A FEW SPOTS MIGHT EVEN
PEAK AT THE CENTURY MARK. DEW POINTS WILL MIX OUT A BIT
INLAND...BUT WILL POOL BEHIND THE SEA BREEZE...WHICH SUPPORTS MOST
HEAT INDICES AS HIGH AS 105-109F...BUT A FEW SPOTS OF THE COASTAL
CORRIDOR WILL MAX OUT AT 110-112F AROUND THE TIME OF THE SEA
BREEZE PASSAGE. OUR HEAT ADVISORY WILL OBVIOUSLY REMAIN ACTIVE.
THE FORECAST FOR HOW CONVECTION WILL PAN OUT IS FAR FROM CERTAIN
GIVEN A WIDE DISPARITY IN VARIOUS MODELS. WE STILL HAVE A SUBTLE
WEAKNESS IN THE RIDGING ALOFT...BUT THAT LOOKS TO BE JUST OFF THE
COAST. THERE WILL BE VARIOUS MESO-SCALE BOUNDARIES SUCH S OUTFLOW
FROM EARLIER MCS THAT MOVED OFF THE MID-ATLANTIC AND ANOTHER FROM
ALABAMA. THERE IS ALSO THE EVER PRESENT PIEDMONT TROUGH AND THE
SEA BREEZE BOUNDARY. THESE FACTORS SHOULD PROVIDE THE NECESSARY
INITIATION...BUT THERE IS STILL A STRONG 3-5C CAP AND UNFAVORABLE
MID LEVEL LAPSE RATES WITH WARM 500 MB TEMPS...IMPLYING THAT
STORMS MAY HAVE A DIFFICULT TIME IN ATTAINING MUCH VERTICAL
GROWTH. ON THE FAVORABLE SIDE OUR LOW LEVEL LAPSE RATES ARE
FAVORABLE AND THERE IS PLENTY OF INSTABILITY WITH SBCAPES FORECAST
TO REACH 4000-4500 J/KG AND LIFTED INDEX OF -6 TO -8C. LOOK FOR
CONVECTION TO GET GOING AROUND 1-2 PM AS WE HIT OUR CONVECTIVE
TEMP IN THE MID 90S.
FOR THE MOMENT A PULSE TYPE ENVIRONMENT SEEMS A MORE LIKELY
CONVECTIVE MODE RATHER THAN MULTI-CELLULAR...BUT IF BOUNDARY
INTERACTIONS AND MERGERS TAKE PLACE THAT COULD CHANGE. WE/LL
MAINTAIN A PROBABILITY FORECAST OF 20-30 PERCENT...HIGHEST INLAND
AND MAINTAIN A CLOSE WATCH ON MESO-SCALE TRENDS TO SEE IF WE NEED
TO RAISE POPS.
DCAPES OF 1000-1200 J/KG AND WINDEX VALUES OF 65 KT WOULD SUPPORT
STRONG DOWNBURST WINDS...AIDED BY PRECIP LOADING WITH PWATS CLOSE
TO THE 90TH PERCENTILE FOR LATE JUNE. OTHER HAZARDS INCLUDE
FREQUENT LIGHTNING STRIKES...VERY HEAVY RAINS DUE TO A STORM
MOTION OF ONLY AROUND 5 MPH AND SHOULD ANY TALL STORMS DEVELOP
THERE IS ALSO HAIL RISK. PROBABILITY OF SEVERE WEATHER IS STILL
TOO LOW TO INCLUDE IN THE HAZARDOUS WEATHER OUTLOOK...MOST NOTABLY
DUE TO THE HRRR SHOWING LITTLE IN THE WAY OF CONVECTIVE
ORGANIZATION.
CONDITIONS SHOULD BE MAINLY QUIET TONIGHT WITH PARTLY CLOUDY SKIES
AND LOWS A BIT WARMER THAN WEDNESDAY MORNING...ESPECIALLY IF TSTMS
COVERAGE IS LOWER END TODAY.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
THURSDAY...PERSISTENT MID LEVEL RIDGE WILL HOLD FAIRLY STRONG FOR
ONE MORE DAY...ALTHOUGH SUBTLE WEAKENING WILL BEGIN TO OCCUR. THE
SURFACE PATTERN WILL CONTINUE TO BE FAIRLY STATIC AS THE AREA
REMAINS ON THE WESTERN PERIPHERY OF ATLANTIC HIGH PRESSURE WITH A
PIEDMONT TROUGH SITUATED INLAND. HIGH TEMPERATURES IN THE MID/UPPER
90S AWAY FROM THE COAST WILL COMBINE WITH MODERATE HUMIDITY LEVELS
TO PRODUCE HEAT INDICES OF 105-108 IN THE AFTERNOON. THUS A HEAT
ADVISORY WILL LIKELY BE NEEDED. LARGE SCALE FORCING WILL LARGELY BE
MISSING HOWEVER CONVECTION WILL DEVELOP AS A RESULT OF SEA BREEZE
AND/OR CONVERGENCE ALONG SURFACE TROUGH. FORECAST SURFACE BASED
CAPE NEAR 3000 J/KG MAY SUPPORT A FEW STRONGER POSSIBLY SEVERE
STORMS...WITH GUSTY WINDS THE PRIMARY THREAT GIVEN DCAPE VALUES IN
EXCESS OF 1000 J/KG. THURSDAY NIGHT...SURFACE LOW PRESSURE WILL
CROSS THE MID-ATLANTIC STATES ABSORBING THE PIEDMONT TROUGH. AN
ATTENDANT FRONT WILL STALL NORTH OF THE AREA. LOWS WILL BE QUITE
MILD RANGING FROM THE MID 70S INLAND TO AROUND 80 ALONG THE COAST.
FRIDAY...AN AREA OF LOW PRESSURE WILL DEVELOP OVER THE CAROLINAS
ALONG THE AFOREMENTIONED STALLED FRONT. DEEP MOISTURE AND PROXIMITY
TO BOUNDARY WILL ALLOW FOR HIGHER COVERAGE OF SHOWERS AND
THUNDERSTORMS. FORECAST CURRENTLY FEATURES HIGH CHANCE POPS OVER
MUCH OF THE AREA DURING PEAK HEATING HOURS. A FEW STRONGER STORMS
WILL BE POSSIBLE ESPECIALLY IN THE NORTHERN ZONES WHERE INSTABILITY
AND MID LEVEL ENVIRONMENT IS MORE FAVORABLE...WITH GUSTY WINDS
PRIMARY THREAT. FORECAST HEAT INDICES MAY BRIEFLY REACH THE LOCAL
HEAT ADVISORY CRITERIA OF 105 IN THE AFTERNOON WITH HIGH
TEMPERATURES IN THE LOW/MID 90S...HOWEVER DURATION AND AREAL EXTENT
WILL BE MARGINAL AT BEST AND GIVEN EXPECTED CONVECTION...THINK A
HEAT ADVISORY WILL LIKELY NOT BE NEEDED. CONVECTION MAY LINGER INTO
THE OVERNIGHT PERIOD...WITH FOCUS SHIFTING MORE TO THE COASTAL
WATERS. LOWS WILL AGAIN BE IN THE MID TO UPPER 70S.
SATURDAY...THE UPPER LEVEL PATTERN WILL BECOME MUCH MORE AMPLIFIED
AS DEEPENING TROUGH AND ASSOCIATED VORT MAX DIGS INTO THE GREAT
LAKES REGION. THIS WILL HELP SEND ANOTHER AREA OF LOW PRESSURE
TOWARDS EAST COAST WHICH WILL EVENTUALLY ENGULF THE STATIONARY
FRONT/LOW. BETTER UPPER SUPPORT...DEEP MOISTURE AND VARIOUS SURFACE
BOUNDARIES WILL ALLOW FOR A FAIRLY ACTIVE DAY WITH STRONGER STORMS
POSSIBLE GIVEN DECENT SHEAR AND FORECAST INSTABILITY. HIGH
TEMPERATURES WILL MAINLY BE IN THE LOW 90S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
BROAD UPPER TROUGH WILL ENCOMPASS THE EASTERN U.S. THROUGH THE LONG
TERM PERIOD. A POTENT SHORTWAVE WILL SEND AN AREA OF LOW PRESSURE
AND ATTENDANT FRONT THROUGH THE FORECAST AREA ON SUNDAY. GIVEN
FORCING FROM UPPER JET...SHORTWAVE ENERGY AND COLD FRONT...IT SHOULD
BE A PRETTY ACTIVE DAY ESPECIALLY GIVEN DECENT SHEAR AND DEEP
MOISTURE. THE FRONT WILL LIKELY PUSH OFF THE COAST EARLY
MONDAY...AND REMAIN STATIONARY OFFSHORE BEFORE DISSIPATING TUESDAY.
WEAK HIGH PRESSURE IS EXPECTED TO PREVAIL BY MID WEEK. TEMPERATURES
WILL BE AT OR BELOW CLIMO THROUGH THE PERIOD.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
VFR THROUGH 12Z THURSDAY. POTENTIAL FOR AFTERNOON AND EVENING
SHOWERS AND TSTMS TODAY IS TOO LOW FOR ANY MENTIONS IN THE CURRENT
TAF CYCLE AT THIS TIME...ESPECIALLY WITH UNCERTAINTIES WITH
TIMING AND COVERAGE.
EXTENDED AVIATION OUTLOOK...BRIEF FLIGHT RESTRICTIONS POSSIBLE IN
AFTERNOON SHOWERS/THUNDERSTORMS...ESPECIALLY THIS WEEKEND.
&&
.MARINE...
THE COASTAL WATERS SYNOPTIC PATTERN IS NOT CHANGING MUCH AND
MARINERS FAMILIAR WITH THE SUMMER PATTERNS WILL NOT GET ANY BIG
SURPRISES THROUGH TONIGHT. SOUTH/SW SEA BREEZE CIRCULATIONS AND SW
NOCTURNAL SURGES WILL PUSH SPEEDS INTO THE 15-20 KT RANGE WITH
SOME HIGHER GUSTS AT FAVORED AREAS SUCH AS THE CHARLESTON LAND/SEA
INTERFACE WITH SEAS 2-4 FT ON AVERAGE...HIGHEST WELL OFFSHORE.
WAVES IN THE HARBOR WILL BUILD TO 1 TO 2 FT THROUGH THIS EVENING.
THURSDAY THROUGH MONDAY...ATLANTIC HIGH PRESSURE WILL PREVAIL OVER
THE COASTAL WATERS WHILE A TROUGH OF LOW PRESSURE PERSISTS INLAND
THROUGH THE REMAINDER OF THE WEEK. A COLD FRONT IS EXPECTED TO
APPROACH THE WATERS OVER THE WEEKEND AND EVENTUALLY STALL AND
DISSIPATE EARLY NEXT WEEK. TIGHTENED PRESSURE GRADIENT WILL KEEP
WINDS FAIRLY ELEVATED THROUGH THE PERIOD. NOCTURNAL JETTING AND
AFTERNOON SEA BREEZE CIRCULATIONS WILL RESULT IN SOUTH/SOUTHWEST
WINDS PEAKING AROUND 15-20 KT...ESPECIALLY ACROSS THE CHARLESTON
COUNTY COASTAL WATERS. GUSTS MAY REACH NEAR SMALL CRAFT ADVISORY
CRITERIA OF 25 KT AT TIMES...AND HEADLINES MAY NEED TO BE
CONSIDERED. SEAS WILL MAINLY BE 2-4 FEET...BUT MAY REACH 5-6 FEET IN
THE OUTER PORTIONS OF THE WATERS DURING SURGES.
&&
.CLIMATE...
RECORD HIGH MINIMUMS FOR JUNE 24TH...
KCHS...79 SET IN 1998.
KCXM...85 SET IN 1998.
KSAV...80 SET IN 1914.
RECORD HIGH MINIMUMS FOR JUNE 25TH...
KCHS...79 SET IN 2010.
KCXM...83 SET IN 1998.
KSAV...80 SET IN 1914.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR GAZ087-088-
099>101-114>119-137>141.
SC...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR SCZ040-042>045-
047>052.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...ECT
LONG TERM...ECT
AVIATION...
MARINE...
CLIMATE...
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
517 PM CDT WED JUN 24 2015
.SHORT TERM...
317 PM CDT
THROUGH SATURDAY...
WILL BE PUSHING BACK THE START TIME OF THE FLASH FLOOD WATCH OVER
EASTERN SECTIONS OF THE AREA TILL AROUND 06 UTC THIS
EVENING...OTHERWISE NO CHANGES TO THE WATCH PLANNED.
THE EARLY MORNING SHOWERS AND THUNDERSTORMS OVER WEST CENTRAL
ILLINOIS PUSHED AN OUTFLOW BOUNDARY SOUTHWARD OVER MISSOURI...AND
THIS HAS EFFECTIVELY PUSHED THE SURFACE WARM FRONT AND BETTER
INSTABILITY FARTHER SOUTH OVER MISSOURI. AS SUCH...I HAVE SOME
CONCERNS THAT THE HEAVY RAIN AND SEVERE THREAT...AT LEAST INITIALLY
THIS EVENING MAY BE DELAYED AND FOCUSED OVER WESTERN PORTIONS OF
ILLINOIS AND IOWA. THE HRRR RUNS HAVE BEEN PICKING UP ON THIS
POSSIBILITY OVER THE PAST COUPLE HOURS...AND WITH THE SURFACE
BOUNDARY STILL OVER CENTRAL AND WESTERN SECTIONS OF MISSOURI...I AM
THINKING IT MAY BE HEADING IN THE RIGHT DIRECTION. WITH THIS IN MIND
I DID CUT BACK ON POPS THIS EVENING OVER EASTERN SECTIONS OF THE
REGION AND HAVE PUSHED THE FLASH FLOOD WATCH OFF UNTIL 05 UTC FOR
THE CHICAGO METRO AREA AND NORTHWESTERN INDIANA.
THE CONVECTIVE ACTIVITY OVER IOWA IS ASSOCIATED WITH AN MCV...AND
THIS MAY MOVE OVER PORTIONS OF NORTHERN ILLINOIS LATE THIS
AFTERNOON AND EARLY THIS EVENING. HOWEVER...IT APPEARS WITH THE
INSTABILITY GRADIENT REMAINING TO OUR SOUTHWEST...THUNDERSTORMS WILL
LIKELY BECOME MORE SCATTERED WITH THE EASTWARD EXTENT OF THIS
PRECIPITATION. THEREFORE...ONLY A FEW LINGERING SHOWERS AND PERHAPS
A FEW THUNDERSTORMS MAY MOVE OVER THE AREA THROUGH EARLY THIS
EVENING.
THUNDERSTORMS WILL STILL LIKELY BEGIN TO DEVELOP UPSTREAM OVER
EASTERN IOWA AND INTO WESTERN ILLINOIS THROUGH THE EVENING A
SOUTHWESTERLY LOW LEVEL JET NOSES INTO THIS AREA. THIS WILL RESULT
IN BACKBULDING AND TRAINING THUNDERSTORMS WITH HEAVY RAINFALL.
HOWEVER...IT APPEARS THE MAIN FOCUS FOR THIS ACTIVITY MAY REMAIN JUST
WEST OF MY AREA...AT LEAST FOR MUCH OF THE EVENING. WITH TIME...IT
APPEARS THE FOCUS MAY BEGIN TO SHIFT EASTWARD INTO NORTHEASTERN
ILLINOIS AND NORTHWESTERN INDIANA...BUT THIS MAY NOT BE UNTIL AFTER
MIDNIGHT TONIGHT. HEAVY RAIN RATES WILL STILL BE A CONCERN...AND IT
APPEARS THE HEAVIEST RAIN MAY FALL SOUTH OF INTERSTATE 88.
THE HEAVY RAIN THREAT WILL CONTINUE INTO THE LATE MORNING/EARLY
AFTERNOON ON THURSDAY...ESPECIALLY SOUTH OF I-80 AS THE SURFACE
SYSTEM MOVES OVER THE AREA. HOWEVER...ONCE THE SURFACE LOW PASSES
EAST...THE FRONTAL BOUNDARY WILL SHIFT SOUTH OF THE AREA LATER IN
THE DAY...BRINGING THE SHOWER AND STORM THREAT TO AN END.
AS FOR THE SEVERE THREAT...IT APPEARS THIS TOO MAY END UP BEING
FARTHER SOUTH THAN PREVIOUSLY THOUGHT. ALTHOUGH UNCERTAINTY REMAINS
AS TO HOW THE SEVERE THREAT WILL EVOLVE TONIGHT. IT APPEARS AT THIS
POINT THAT THE HIGHEST THREAT MAY END UP BEING PRIMARILY SOUTH OF
INTERSTATE 80...AND BE MAINLY A DAMAGING WIND THREAT.
MUCH COOLER WEATHER WILL BUILD IN OVER MUCH OF THE REGION IN THE
WAKE OF THIS FRONT. ANOTHER SYSTEM LOOKS TO DEVELOP AND IMPACT THE
OHIO VALLEY REGION LATER FRIDAY INTO EARLY SATURDAY AS AN UPPER
TROUGH DIGS OVER THE LOWER GREAT LAKES REGION. IT APPEARS MOST OF THE
PRECIP WITH THIS SYSTEM WILL REMAIN SOUTH OF MOST OF MY AREA. COOL
CONDITIONS WILL BE THE RULE FOR A FEW DAYS...WITH A BREAK IN THE
WEATHER...FINALLY.
KJB
&&
.LONG TERM...
346 AM CDT
ADVERTISED UPPER LEVEL PATTERN SHIFT TO A MUCH HIGHER AMPLITUDE FLOW
WILL BE IN PLACE BY SUNDAY. THIS HIGH AMPLIFIED PATTERN WILL BREAK
DOWN GRADUALLY WITH TIME THROUGH THE 4 DAY PERIOD BUT A NORTHWEST
FLOW ALOFT WILL PERSIST THROUGH WEDNESDAY. WHILE MODELS TO DEPICT A
SERIES OF UPPER LEVEL SHORTWAVES TO SLIDE ACROSS THE AREA THROUGH
THE PERIOD THE NATURE OF THE PRECIPITATION SYSTEMS THESE FEATURES
WILL PRODUCE WILL BE MUCH DIFFERENT COMPARED TO THE PAST 3 WEEKS.
DESPITE MENTION OF POPS EACH DAY THERE WILL BE LONG DRY SPELLS IN
BETWEEN AND ANY RAIN THAT DOES FALL WILL BE GENERALLY BRIEF AND
RELATIVELY LIGHT. THE BETTER WINDOWS FOR RAINFALL APPEAR TO BE
DIURNALLY ENHANCED DURING THE AFTERNOONS MONDAY AND TUESDAY AND
ASSOCIATED WITH A PAIR OF WEAK SECONDARY COLD FRONTS BEING DRIVEN
SOUTH VIA UPPER LEVEL IMPULSES. TEMPERATURES WILL REMAIN BELOW
AVERAGE THROUGH THE PERIOD WITH LAKE BREEZES EXPECTED SUNDAY AND
WEDNESDAY... AND POSSIBLY LATE TUESDAY AS WELL.
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* AREA OF LGT-MOD RA TO MOVE ACROSS TERMINALS ROUGHLY 2330Z-0200Z.
LITTLE IN WAY OF LIGHTNING EXPECTED...THOUGH BRIEF 4-6SM VIS AND
MID/HIGH BASED MVFR CIG POSSIBLE DURING PRECIP.
* LIGHT/VARIABLE WINDS LESS THAN 10 KT INTO EARLY THIS EVENING...
THOUGH MAY FAVOR A TREND IN DIRECTION FROM SW BACKING TO SE OR E
BY EARLY EVENING.
* THUNDERSTORM POTENTIAL APPEARS TO BE DECREASING THROUGH MIDNIGHT
AS FOCUS EXPECTED TO BE FROM WEST/CENTRAL IA INTO CENTRAL IL AT
THIS TIME.
RATZER
//DISCUSSION...UPDATED 22Z...
MCV...MESOSCALE VORTICITY CENTER...CURRENTLY CENTERED JUST EAST OF
KCID/CEDAR RAPIDS IOWA AT 22Z. AREA OF LIGHT-MODERATE RAIN IN
ADVANCE OF THIS MID-LEVEL FEATURE EXTENDS INTO NORTHWEST/NORTH
CENTRAL IL AND EXTRAPOLATION OF RADAR FEATURES SUGGESTS A PERIOD
OF LIGHT-MODERATE RAIN FOR TERMINALS ALREADY BEGUN AT KRFD...WILL
ARRIVE CHI TERMINALS BETWEEN 23-00Z. LIGHTNING DETECTION NETWORK
SHOWING DECREASING TREND WITH INTRA-CLOUD DISCHARGES...AND
DECREASING INSTABILITY FARTHER EAST SUGGESTS ONLY LOW THUNDER
PROBABILITY FOR TERMINALS. TIMING OF TRAILING EDGE SUGGESTS RAIN
ENDING AROUND 01Z FOR KRFD...02Z-ISH FOR CHICAGO TERMINALS.
THUNDER THREAT LATER THIS EVENING LOOKS LATER THAN PREVIOUS
FORECAST...AND HAVE PUSHED THUNDER BACK TO AFTER MIDNIGHT.
RATZER
PREVIOUS DISCUSSION FROM 18Z...
AT THE SURFACE...A LARGE AREA OF HIGH PRESSURE IS CENTERED ALONG
THE IN/OH BORDER AS A MID LEVEL IMPULSE CROSSING THE MIDDLE
MISSISSIPPI VALLEY IS BRINGING AN AREA OF SHOWERS AND
THUNDERSTORMS FROM IOWA THROUGH CENTRAL IL TO CENTRAL IN. BASED ON
THE LATEST RADAR TRENDS...EXPECT THAT ANY PCPN AND TS SHOULD
REMAIN SOUTH OF OF THE TERMINALS EARLY THIS EVENING...THROUGH IT
COULD CLIP THE SOUTHERN PORTIONS OF THE C90 TRACON AREA. AS THE
CENTER OF THE HIGH CONTINUES TO SHIFT TO THE EAST...WINDS HAVE
BECOME SSWLY AND ARE INCREASING TO ARND 10KT. LATEST RADAR IMAGERY
AND COASTAL OBSERVATIONS SHOW A LAKE BREEZE MOVING ONSHORE NEAR
KUGN...BUT THERE IS LITTLE WESTWARD PROGRESSION AND DO NOT EXPECT
THAT THE BOUNDARY WILL REACH AS FAR WEST AS ORD/MDW.
RATHER...EXPECT THAT WINDS WILL GRADUALLY BACK TO MORE SELY
THROUGH THE AFTERNOON AND INTO THE EVENING IN RESPONSE TO THE
LARGER SCALE PRESSURE PATTERN WITH THE HIGH MOVING OFF TO THE EAST
AND LOW PRESSURE DEVELOPING OVER THE CNTRL PLAINS.
THE OTHER CONCERN FOR THE PERIOD WILL BE TIMING THE NEXT ROUND OF
THUNDERSTORMS TO IMPACT THE REGION. WHILE THE ONGOING PCPN SHOULD
REMAIN SOUTH OF THE TERMINALS...CONFIDENCE IS HIGHER THAT ANOTHER
ROUND OF THUNDERSTORMS WILL DEVELOP TONIGHT OVER THE CNTRL
PLAINS/IOWA AND THEN TRACK EASTWARD. LATEST GUIDANCE IS A LITTLE
FASTER THAN PREVIOUS MODEL RUNS AND SUGGESTS THAT TS COULD REACH
RFD BY ARND 03Z...AND THEN QUICKLY PUSHING TO THE EAST ACROSS THE
CHICAGO AREA TERMINALS. WHILE CONFIDENCE IS RELATIVELY HIGH IN TS
IMPACTING THE TERMINALS OVERNIGHT TONIGHT...TIMING AND DURATION IS
A LITTLE LOWER. ALSO...AS THE MAIN SFC LOW TRACKS ALONG A
DEVELOPING WARM FRONT EXPECTED TO SET THROUGH CNTRL OR NRN IL/IN
AND WITH UPPER LEVEL FLOW SETTING UP TO BE PARALLEL TO THE SFC
FRONT...AN EXTENDED PERIOD OF TSRA IMPACTING THE TERMINALS IS
QUITE POSSIBLE OVERNIGHT AND POSSIBLY EVEN INTO TOMORROW MORNING.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* MEDIUM CONFIDENCE IN WIND DIRECTION TRENDS...HIGH CONFIDENCE IN
WINDS GENERALLY LESS THAN 10 KTS THIS EVE.
* HIGH CONFIDENCE IN RA TIMING AND GENERAL LACK OF TSRA THIS
EVENING.
* LOW CONFIDENCE IN TSRA AFFECTING TERMINALS OVERNIGHT AND WITH
TIMING IF THEY DO.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR. WX NIL. NELY WINDS.
FRIDAY...VFR. WX NIL. NELY WINDS.
SATURDAY...VFR. WX NIL. NELY WINDS BACKING NWLY LATE.
SUNDAY...CHANCE TSRA. MVFR POSSIBLE. NWLY WINDS BACKING SWLY.
MONDAY...CHANCE TSRA. MVFR POSSIBLE. SWLY WINDS VEERING NWLY
TUESDAY...SLIGHT CHANCE TSRA. VRBL WINDS.
KREIN
&&
.MARINE...
258 PM CDT
HIGH PRESSURE RIDGING ACROSS THE SOUTHERN GREAT LAKES WILL EXIT
THE AREA TO THE EAST THIS EVENING ALLOWING LOW PRESSURE OVER THE
CENTRAL PLAINS TO MOVE NORTHEAST INTO NORTHERN ILLINOIS BY
THURSDAY MORNING. MEANWHILE A WEAK COLD FRONT ACROSS THE NORTHERN
GREAT LAKES WILL SAG SOUTH AHEAD OF HIGH PRESSURE OVER ONTARIO AND
WASH OUT AS THE AFFOREMENTIONED LOW PRESSURE AREA MOVES INTO
ILLINOIS. AS THIS LOW MOVES EAST TO OHIO THURSDAY NIGHT ITS
ASSOCIATED COLD FRONT WILL DROP SOUTH AWAY FROM THE AREA ALLOWING
ANOTHER AREA OF WEAK HIGH PRESSURE TO BUILD ACROSS THE GREAT
LAKES. THIS HIGH WILL DRIFT EAST SUNDAY NIGHT INTO MONDAY ALLOWING
A SECONDARY COLD FRONT TO SAG SOUTH ACROSS THE NORTHERN GREAT
LAKES.
ED F
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ008-ILZ010-ILZ011-ILZ019-
ILZ021-ILZ032-ILZ039 UNTIL 1 PM THURSDAY.
FLASH FLOOD WATCH...ILZ005-ILZ006-ILZ012-ILZ013-ILZ014-ILZ020-
ILZ022-ILZ023-ILZ033...MIDNIGHT THURSDAY TO 1 PM THURSDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-
INZ019...MIDNIGHT THURSDAY TO 1 PM THURSDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
346 PM CDT WED JUN 24 2015
.SHORT TERM...
317 PM CDT
THROUGH SATURDAY...
WILL BE PUSHING BACK THE START TIME OF THE FLASH FLOOD WATCH OVER
EASTERN SECTIONS OF THE AREA TILL AROUND 06 UTC THIS
EVENING...OTHERWISE NO CHANGES TO THE WATCH PLANNED.
THE EARLY MORNING SHOWERS AND THUNDERSTORMS OVER WEST CENTRAL
ILLINOIS PUSHED AN OUTFLOW BOUNDARY SOUTHWARD OVER MISSOURI...AND
THIS HAS EFFECTIVELY PUSHED THE SURFACE WARM FRONT AND BETTER
INSTABILITY FARTHER SOUTH OVER MISSOURI. AS SUCH...I HAVE SOME
CONCERNS THAT THE HEAVY RAIN AND SEVERE THREAT...AT LEAST INITIALLY
THIS EVENING MAY BE DELAYED AND FOCUSED OVER WESTERN PORTIONS OF
ILLINOIS AND IOWA. THE HRRR RUNS HAVE BEEN PICKING UP ON THIS
POSSIBILITY OVER THE PAST COUPLE HOURS...AND WITH THE SURFACE
BOUNDARY STILL OVER CENTRAL AND WESTERN SECTIONS OF MISSOURI...I AM
THINKING IT MAY BE HEADING IN THE RIGHT DIRECTION. WITH THIS IN MIND
I DID CUT BACK ON POPS THIS EVENING OVER EASTERN SECTIONS OF THE
REGION AND HAVE PUSHED THE FLASH FLOOD WATCH OFF UNTIL 05 UTC FOR
THE CHICAGO METRO AREA AND NORTHWESTERN INDIANA.
THE CONVECTIVE ACTIVITY OVER IOWA IS ASSOCIATED WITH AN MCV...AND
THIS MAY MOVE OVER PORTIONS OF NORTHERN ILLINOIS LATE THIS
AFTERNOON AND EARLY THIS EVENING. HOWEVER...IT APPEARS WITH THE
INSTABILITY GRADIENT REMAINING TO OUR SOUTHWEST...THUNDERSTORMS WILL
LIKELY BECOME MORE SCATTERED WITH THE EASTWARD EXTENT OF THIS
PRECIPITATION. THEREFORE...ONLY A FEW LINGERING SHOWERS AND PERHAPS
A FEW THUNDERSTORMS MAY MOVE OVER THE AREA THROUGH EARLY THIS
EVENING.
THUNDERSTORMS WILL STILL LIKELY BEGIN TO DEVELOP UPSTREAM OVER
EASTERN IOWA AND INTO WESTERN ILLINOIS THROUGH THE EVENING A
SOUTHWESTERLY LOW LEVEL JET NOSES INTO THIS AREA. THIS WILL RESULT
IN BACKBULDING AND TRAINING THUNDERSTORMS WITH HEAVY RAINFALL.
HOWEVER...IT APPEARS THE MAIN FOCUS FOR THIS ACTIVITY MAY REMAIN JUST
WEST OF MY AREA...AT LEAST FOR MUCH OF THE EVENING. WITH TIME...IT
APPEARS THE FOCUS MAY BEGIN TO SHIFT EASTWARD INTO NORTHEASTERN
ILLINOIS AND NORTHWESTERN INDIANA...BUT THIS MAY NOT BE UNTIL AFTER
MIDNIGHT TONIGHT. HEAVY RAIN RATES WILL STILL BE A CONCERN...AND IT
APPEARS THE HEAVIEST RAIN MAY FALL SOUTH OF INTERSTATE 88.
THE HEAVY RAIN THREAT WILL CONTINUE INTO THE LATE MORNING/EARLY
AFTERNOON ON THURSDAY...ESPECIALLY SOUTH OF I-80 AS THE SURFACE
SYSTEM MOVES OVER THE AREA. HOWEVER...ONCE THE SURFACE LOW PASSES
EAST...THE FRONTAL BOUNDARY WILL SHIFT SOUTH OF THE AREA LATER IN
THE DAY...BRINGING THE SHOWER AND STORM THREAT TO AN END.
AS FOR THE SEVERE THREAT...IT APPEARS THIS TOO MAY END UP BEING
FARTHER SOUTH THAN PREVIOUSLY THOUGHT. ALTHOUGH UNCERTAINTY REMAINS
AS TO HOW THE SEVERE THREAT WILL EVOLVE TONIGHT. IT APPEARS AT THIS
POINT THAT THE HIGHEST THREAT MAY END UP BEING PRIMARILY SOUTH OF
INTERSTATE 80...AND BE MAINLY A DAMAGING WIND THREAT.
MUCH COOLER WEATHER WILL BUILD IN OVER MUCH OF THE REGION IN THE
WAKE OF THIS FRONT. ANOTHER SYSTEM LOOKS TO DEVELOP AND IMPACT THE
OHIO VALLEY REGION LATER FRIDAY INTO EARLY SATURDAY AS AN UPPER
TROUGH DIGS OVER THE LOWER GREAT LAKES REGION. IT APPEARS MOST OF THE
PRECIP WITH THIS SYSTEM WILL REMAIN SOUTH OF MOST OF MY AREA. COOL
CONDITIONS WILL BE THE RULE FOR A FEW DAYS...WITH A BREAK IN THE
WEATHER...FINALLY.
KJB
&&
.LONG TERM...
346 AM CDT
ADVERTISED UPPER LEVEL PATTERN SHIFT TO A MUCH HIGHER AMPLITUDE FLOW
WILL BE IN PLACE BY SUNDAY. THIS HIGH AMPLIFIED PATTERN WILL BREAK
DOWN GRADUALLY WITH TIME THROUGH THE 4 DAY PERIOD BUT A NORTHWEST
FLOW ALOFT WILL PERSIST THROUGH WEDNESDAY. WHILE MODELS TO DEPICT A
SERIES OF UPPER LEVEL SHORTWAVES TO SLIDE ACROSS THE AREA THROUGH
THE PERIOD THE NATURE OF THE PRECIPITATION SYSTEMS THESE FEATURES
WILL PRODUCE WILL BE MUCH DIFFERENT COMPARED TO THE PAST 3 WEEKS.
DESPITE MENTION OF POPS EACH DAY THERE WILL BE LONG DRY SPELLS IN
BETWEEN AND ANY RAIN THAT DOES FALL WILL BE GENERALLY BRIEF AND
RELATIVELY LIGHT. THE BETTER WINDOWS FOR RAINFALL APPEAR TO BE
DIURNALLY ENHANCED DURING THE AFTERNOONS MONDAY AND TUESDAY AND
ASSOCIATED WITH A PAIR OF WEAK SECONDARY COLD FRONTS BEING DRIVEN
SOUTH VIA UPPER LEVEL IMPULSES. TEMPERATURES WILL REMAIN BELOW
AVERAGE THROUGH THE PERIOD WITH LAKE BREEZES EXPECTED SUNDAY AND
WEDNESDAY... AND POSSIBLY LATE TUESDAY AS WELL.
&&
ED F
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* CHANCE OF LAKE BREEZE DEVELOPMENT LATE THIS AFTERNOON.
* THUNDERSTORMS LIKELY OVERNIGHT TONIGHT...MVFR-IFR CIGS/VIS
LIKELY.
KREIN
//DISCUSSION...UPDATED 18Z...
AT THE SURFACE...A LARGE AREA OF HIGH PRESSURE IS CENTERED ALONG
THE IN/OH BORDER AS A MID LEVEL IMPULSE CROSSING THE MIDDLE
MISSISSIPPI VALLEY IS BRINGING AN AREA OF SHOWERS AND
THUNDERSTORMS FROM IOWA THROUGH CENTRAL IL TO CENTRAL IN. BASED
ON THE LATEST RADAR TRENDS...EXPECT THAT ANY PCPN AND TS SHOULD
REMAIN SOUTH OF OF THE TERMINALS EARLY THIS EVENING...THROUGH IT
COULD CLIP THE SOUTHERN PORTIONS OF THE C90 TRACON AREA. AS THE
CENTER OF THE HIGH CONTINUES TO SHIFT TO THE EAST...WINDS HAVE
BECOME SSWLY AND ARE INCREASING TO ARND 10KT. LATEST RADAR IMAGERY
AND COASTAL OBSERVATIONS SHOW A LAKE BREEZE MOVING ONSHORE NEAR
KUGN...BUT THERE IS LITTLE WESTWARD PROGRESSION AND DO NOT EXPECT
THAT THE BOUNDARY WILL REACH AS FAR WEST AS ORD/MDW.
RATHER...EXPECT THAT WINDS WILL GRADUALLY BACK TO MORE SELY
THROUGH THE AFTERNOON AND INTO THE EVENING IN RESPONSE TO THE
LARGER SCALE PRESSURE PATTERN WITH THE HIGH MOVING OFF TO THE EAST
AND LOW PRESSURE DEVELOPING OVER THE CNTRL PLAINS.
THE OTHER CONCERN FOR THE PERIOD WILL BE TIMING THE NEXT ROUND OF
THUNDERSTORMS TO IMPACT THE REGION. WHILE THE ONGOING PCPN SHOULD
REMAIN SOUTH OF THE TERMINALS...CONFIDENCE IS HIGHER THAT ANOTHER
ROUND OF THUNDERSTORMS WILL DEVELOP TONIGHT OVER THE CNTRL
PLAINS/IOWA AND THEN TRACK EASTWARD. LATEST GUIDANCE IS A LITTLE
FASTER THAN PREVIOUS MODEL RUNS AND SUGGESTS THAT TS COULD REACH
RFD BY ARND 03Z...AND THEN QUICKLY PUSHING TO THE EAST ACROSS THE
CHICAGO AREA TERMINALS. WHILE CONFIDENCE IS RELATIVELY HIGH IN TS
IMPACTING THE TERMINALS OVERNIGHT TONIGHT...TIMING AND DURATION IS
A LITTLE LOWER. ALSO...AS THE MAIN SFC LOW TRACKS ALONG A
DEVELOPING WARM FRONT EXPECTED TO SET THROUGH CNTRL OR NRN IL/IN
AND WITH UPPER LEVEL FLOW SETTING UP TO BE PARALLEL TO THE SFC
FRONT...AN EXTENDED PERIOD OF TSRA IMPACTING THE TERMINALS IS
QUITE POSSIBLE OVERNIGHT AND POSSIBLY EVEN INTO TOMORROW MORNING.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM TO HIGH CONFIDENCE IN GENERAL WIND TRENDS.
* MEDIUM CONFIDENCE IN LAKE BREEZE DETAILS...AND THAT THE LAKE
BREEZE BOUNDARY WILL REMAIN EAST OF THE TERMINALS.
* MEDIUM TO HIGH CONFIDENCE IN TS IMPACTING THE TERMINALS THIS
EVENING AND TONIGHT...LOWER CONFIDENCE IN EXACT TIMING AND
DURATION.
* MEDIUM CONFIDENCE IN A PERIOD OF MVFR-IFR CIGS/VIS WITH THE
TSRA/PCPN OVERNIGHT TONIGHT AND INTO TOMORROW MORNING.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR. WX NIL. NELY WINDS.
FRIDAY...VFR. WX NIL. NELY WINDS.
SATURDAY...VFR. WX NIL. NELY WINDS BACKING NWLY LATE.
SUNDAY...CHANCE TSRA. MVFR POSSIBLE. NWLY WINDS BACKING SWLY.
MONDAY...CHANCE TSRA. MVFR POSSIBLE. SWLY WINDS VEERING NWLY
TUESDAY...SLIGHT CHANCE TSRA. VRBL WINDS.
KREIN
&&
.MARINE...
258 PM CDT
HIGH PRESSURE RIDGING ACROSS THE SOUTHERN GREAT LAKES WILL EXIT
THE AREA TO THE EAST THIS EVENING ALLOWING LOW PRESSURE OVER THE
CENTRAL PLAINS TO MOVE NORTHEAST INTO NORTHERN ILLINOIS BY
THURSDAY MORNING. MEANWHILE A WEAK COLD FRONT ACROSS THE NORTHERN
GREAT LAKES WILL SAG SOUTH AHEAD OF HIGH PRESSURE OVER ONTARIO AND
WASH OUT AS THE AFFOREMENTIONED LOW PRESSURE AREA MOVES INTO
ILLINOIS. AS THIS LOW MOVES EAST TO OHIO THURSDAY NIGHT ITS
ASSOCIATED COLD FRONT WILL DROP SOUTH AWAY FROM THE AREA ALLOWING
ANOTHER AREA OF WEAK HIGH PRESSURE TO BUILD ACROSS THE GREAT
LAKES. THIS HIGH WILL DRIFT EAST SUNDAY NIGHT INTO MONDAY ALLOWING
A SECONDARY COLD FRONT TO SAG SOUTH ACROSS THE NORTHERN GREAT
LAKES.
ED F
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ008-ILZ010-ILZ011-ILZ019-
ILZ021-ILZ032-ILZ039...7 PM WEDNESDAY TO 1 PM THURSDAY.
FLASH FLOOD WATCH...ILZ005-ILZ006-ILZ012-ILZ013-ILZ014-ILZ020-
ILZ022-ILZ023-ILZ033...MIDNIGHT THURSDAY TO 1 PM THURSDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-
INZ019...MIDNIGHT THURSDAY TO 1 PM THURSDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
318 PM CDT WED JUN 24 2015
.SHORT TERM...
317 PM CDT
THROUGH SATURDAY...
WILL BE PUSHING BACK THE START TIME OF THE FLASH FLOOD WATCH OVER
EASTERN SECTIONS OF THE AREA TILL AROUND 06 UTC THIS
EVENING...OTHERWISE NO CHANGES TO THE WATCH PLANNED.
THE EARLY MORNING SHOWERS AND THUNDERSTORMS OVER WEST CENTRAL
ILLINOIS PUSHED AN OUTFLOW BOUNDARY SOUTHWARD OVER MISSOURI...AND
THIS HAS EFFECTIVELY PUSHED THE SURFACE WARM FRONT AND BETTER
INSTABILITY FARTHER SOUTH OVER MISSOURI. AS SUCH...I HAVE SOME
CONCERNS THAT THE HEAVY RAIN AND SEVERE THREAT...AT LEAST INITIALLY
THIS EVENING MAY BE DELAYED AND FOCUSED OVER WESTERN PORTIONS OF
ILLINOIS AND IOWA. THE HRRR RUNS HAVE BEEN PICKING UP ON THIS
POSSIBILITY OVER THE PAST COUPLE HOURS...AND WITH THE SURFACE
BOUNDARY STILL OVER CENTRAL AND WESTERN SECTIONS OF MISSOURI...I AM
THINKING IT MAY BE HEADING IN THE RIGHT DIRECTION. WITH THIS IN MIND
I DID CUT BACK ON POPS THIS EVENING OVER EASTERN SECTIONS OF THE
REGION AND HAVE PUSHED THE FLASH FLOOD WATCH OFF UNTIL 05 UTC FOR
THE CHICAGO METRO AREA AND NORTHWESTERN INDIANA.
THE CONVECTIVE ACTIVITY OVER IOWA IS ASSOCIATED WITH AN MCV...AND
THIS MAY MOVE OVER PORTIONS OF NORTHERN ILLINOIS LATE THIS
AFTERNOON AND EARLY THIS EVENING. HOWEVER...IT APPEARS WITH THE
INSTABILITY GRADIENT REMAINING TO OUR SOUTHWEST...THUNDERSTORMS WILL
LIKELY BECOME MORE SCATTERED WITH THE EASTWARD EXTENT OF THIS
PRECIPITATION. THEREFORE...ONLY A FEW LINGERING SHOWERS AND PERHAPS
A FEW THUNDERSTORMS MAY MOVE OVER THE AREA THROUGH EARLY THIS
EVENING.
THUNDERSTORMS WILL STILL LIKELY BEGIN TO DEVELOP UPSTREAM OVER
EASTERN IOWA AND INTO WESTERN ILLINOIS THROUGH THE EVENING A
SOUTHWESTERLY LOW LEVEL JET NOSES INTO THIS AREA. THIS WILL RESULT
IN BACKBULDING AND TRAINING THUNDERSTORMS WITH HEAVY RAINFALL.
HOWEVER...IT APPEARS THE MAIN FOCUS FOR THIS ACTIVITY MAY REMAIN JUST
WEST OF MY AREA...AT LEAST FOR MUCH OF THE EVENING. WITH TIME...IT
APPEARS THE FOCUS MAY BEGIN TO SHIFT EASTWARD INTO NORTHEASTERN
ILLINOIS AND NORTHWESTERN INDIANA...BUT THIS MAY NOT BE UNTIL AFTER
MIDNIGHT TONIGHT. HEAVY RAIN RATES WILL STILL BE A CONCERN...AND IT
APPEARS THE HEAVIEST RAIN MAY FALL SOUTH OF INTERSTATE 88.
THE HEAVY RAIN THREAT WILL CONTINUE INTO THE LATE MORNING/EARLY
AFTERNOON ON THURSDAY...ESPECIALLY SOUTH OF I-80 AS THE SURFACE
SYSTEM MOVES OVER THE AREA. HOWEVER...ONCE THE SURFACE LOW PASSES
EAST...THE FRONTAL BOUNDARY WILL SHIFT SOUTH OF THE AREA LATER IN
THE DAY...BRINGING THE SHOWER AND STORM THREAT TO AN END.
AS FOR THE SEVERE THREAT...IT APPEARS THIS TOO MAY END UP BEING
FARTHER SOUTH THAN PREVIOUSLY THOUGHT. ALTHOUGH UNCERTAINTY REMAINS
AS TO HOW THE SEVERE THREAT WILL EVOLVE TONIGHT. IT APPEARS AT THIS
POINT THAT THE HIGHEST THREAT MAY END UP BEING PRIMARILY SOUTH OF
INTERSTATE 80...AND BE MAINLY A DAMAGING WIND THREAT.
MUCH COOLER WEATHER WILL BUILD IN OVER MUCH OF THE REGION IN THE
WAKE OF THIS FRONT. ANOTHER SYSTEM LOOKS TO DEVELOP AND IMPACT THE
OHIO VALLEY REGION LATER FRIDAY INTO EARLY SATURDAY AS AN UPPER
TROUGH DIGS OVER THE LOWER GREAT LAKES REGION. IT APPEARS MOST OF THE
PRECIP WITH THIS SYSTEM WILL REMAIN SOUTH OF MOST OF MY AREA. COOL
CONDITIONS WILL BE THE RULE FOR A FEW DAYS...WITH A BREAK IN THE
WEATHER...FINALLY.
KJB
&&
.LONG TERM...
340 AM CDT
THURSDAY THROUGH TUESDAY...
THE UPPER LEVEL ZONAL FLOW FINALLY SHIFTS EAST LATE THIS WEEK AS AN
UPPER LEVEL TROUGH MOVES OVER THE REGION FRIDAY NIGHT. THE TROUGH
AXIS SHIFTS EAST SATURDAY WITH NORTHWEST FLOW SUNDAY. ANOTHER WEAKER
TROUGH IS POSSIBLE EARLY NEXT WEEK.
A SFC LOW WILL BE OVER NORTHERN IL AND NORTHWEST IN THURSDAY MORNING
AS A DYING MCS SLOWLY SHIFTS EAST. RAISED QPF AMOUNTS THURSDAY
MORNING AS THE DYING MCS SHOULD PRODUCE AT LEAST ANOTHER 0.35-0.5
INCHES OF RAIN SOUTH OF I-88. GUIDANCE DIFFERS ON HOW QUICKLY THE
MCS WILL EXIT THE REGION...BUT HAVE HIGH CONFIDENCE IN DRY
CONDITIONS THURSDAY NIGHT.
SADLY THERE IS A VERY SMALL BREAK BEFORE THE NEXT LOW PRESSURE
BRINGS MORE RAIN AND STORMS TO AREAS SOUTH OF I-80 FRIDAY. THE NEXT
LOW FORMS OVER THE SOUTHERN PLAINS THURSDAY NIGHT. IT THEN PASSES
OVER THE MID MISSISSIPPI VALLEY AND ALONG THE OHIO RIVER THROUGH
SATURDAY NIGHT. IT LOOKS LIKE THE MAJORITY OF PRECIP WILL FALL OVER
CENTRAL AND SOUTHERN IL...BUT KEPT A SLIGHT CHANCE TO CHANCE OF
THUNDERSTORMS SOUTH OF I-88. WE FINALLY SEE A DRY SPELL LATE THIS
WEEK AS THE LOW SHIFTS EAST AND HIGH PRESSURE SPREADS OVERHEAD.
THE NEXT CHANCE OF RAIN AND STORMS ARRIVES EARLY NEXT WEEK AS AN
UPPER LEVEL TROUGH SWINGS THROUGH. GUIDANCE DIFFERS ON HOW STRONG
THE TROUGH WILL BE AND HOW FAR SOUTH IT WILL TRAVEL...BUT HAVE
ENOUGH CONFIDENCE TO KEEP A CHANCE OF PRECIP IN THE FORECAST. WE
COULD SEE MULTIPLE VORTICITY STREAMERS SWING THROUGH AS THE TROUGH
SITS OVERHEAD SO KEPT A CHANCE OF PRECIP FROM SUNDAY NIGHT THROUGH
TUESDAY. DESPITE THE CONSTANT CHANCE OF RAIN...ONLY EXPECTING
PERIODS OF SHOWERS AND STORMS AT THIS POINT AND NOT COMPLETE
RAIN OUTS.
FOR TEMPS...THURSDAY LOOKS LIKE THE WARMEST DAY WITH HIGHS IN THE
UPPER 70S TO LOW 80S. LAKE COOLING WILL KEEP LAKEFRONT LOCATIONS IN
THE LOW 70S. COOLER AIR SINKS SOUTH THURSDAY NIGHT LEADING TO HIGH
TEMPS FRIDAY IN THE 70S WITH 60S ALONG THE LAKE. A SLOW WARM UP IS
EXPECTED WITH HIGHS BACK IN THE LOW 80S TUESDAY.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* CHANCE OF LAKE BREEZE DEVELOPMENT LATE THIS AFTERNOON.
* THUNDERSTORMS LIKELY OVERNIGHT TONIGHT...MVFR-IFR CIGS/VIS
LIKELY.
KREIN
//DISCUSSION...UPDATED 18Z...
AT THE SURFACE...A LARGE AREA OF HIGH PRESSURE IS CENTERED ALONG
THE IN/OH BORDER AS A MID LEVEL IMPULSE CROSSING THE MIDDLE
MISSISSIPPI VALLEY IS BRINGING AN AREA OF SHOWERS AND
THUNDERSTORMS FROM IOWA THROUGH CENTRAL IL TO CENTRAL IN. BASED
ON THE LATEST RADAR TRENDS...EXPECT THAT ANY PCPN AND TS SHOULD
REMAIN SOUTH OF OF THE TERMINALS EARLY THIS EVENING...THROUGH IT
COULD CLIP THE SOUTHERN PORTIONS OF THE C90 TRACON AREA. AS THE
CENTER OF THE HIGH CONTINUES TO SHIFT TO THE EAST...WINDS HAVE
BECOME SSWLY AND ARE INCREASING TO ARND 10KT. LATEST RADAR IMAGERY
AND COASTAL OBSERVATIONS SHOW A LAKE BREEZE MOVING ONSHORE NEAR
KUGN...BUT THERE IS LITTLE WESTWARD PROGRESSION AND DO NOT EXPECT
THAT THE BOUNDARY WILL REACH AS FAR WEST AS ORD/MDW.
RATHER...EXPECT THAT WINDS WILL GRADUALLY BACK TO MORE SELY
THROUGH THE AFTERNOON AND INTO THE EVENING IN RESPONSE TO THE
LARGER SCALE PRESSURE PATTERN WITH THE HIGH MOVING OFF TO THE EAST
AND LOW PRESSURE DEVELOPING OVER THE CNTRL PLAINS.
THE OTHER CONCERN FOR THE PERIOD WILL BE TIMING THE NEXT ROUND OF
THUNDERSTORMS TO IMPACT THE REGION. WHILE THE ONGOING PCPN SHOULD
REMAIN SOUTH OF THE TERMINALS...CONFIDENCE IS HIGHER THAT ANOTHER
ROUND OF THUNDERSTORMS WILL DEVELOP TONIGHT OVER THE CNTRL
PLAINS/IOWA AND THEN TRACK EASTWARD. LATEST GUIDANCE IS A LITTLE
FASTER THAN PREVIOUS MODEL RUNS AND SUGGESTS THAT TS COULD REACH
RFD BY ARND 03Z...AND THEN QUICKLY PUSHING TO THE EAST ACROSS THE
CHICAGO AREA TERMINALS. WHILE CONFIDENCE IS RELATIVELY HIGH IN TS
IMPACTING THE TERMINALS OVERNIGHT TONIGHT...TIMING AND DURATION IS
A LITTLE LOWER. ALSO...AS THE MAIN SFC LOW TRACKS ALONG A
DEVELOPING WARM FRONT EXPECTED TO SET THROUGH CNTRL OR NRN IL/IN
AND WITH UPPER LEVEL FLOW SETTING UP TO BE PARALLEL TO THE SFC
FRONT...AN EXTENDED PERIOD OF TSRA IMPACTING THE TERMINALS IS
QUITE POSSIBLE OVERNIGHT AND POSSIBLY EVEN INTO TOMORROW MORNING.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM TO HIGH CONFIDENCE IN GENERAL WIND TRENDS.
* MEDIUM CONFIDENCE IN LAKE BREEZE DETAILS...AND THAT THE LAKE
BREEZE BOUNDARY WILL REMAIN EAST OF THE TERMINALS.
* MEDIUM TO HIGH CONFIDENCE IN TS IMPACTING THE TERMINALS THIS
EVENING AND TONIGHT...LOWER CONFIDENCE IN EXACT TIMING AND
DURATION.
* MEDIUM CONFIDENCE IN A PERIOD OF MVFR-IFR CIGS/VIS WITH THE
TSRA/PCPN OVERNIGHT TONIGHT AND INTO TOMORROW MORNING.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR. WX NIL. NELY WINDS.
FRIDAY...VFR. WX NIL. NELY WINDS.
SATURDAY...VFR. WX NIL. NELY WINDS BACKING NWLY LATE.
SUNDAY...CHANCE TSRA. MVFR POSSIBLE. NWLY WINDS BACKING SWLY.
MONDAY...CHANCE TSRA. MVFR POSSIBLE. SWLY WINDS VEERING NWLY
TUESDAY...SLIGHT CHANCE TSRA. VRBL WINDS.
KREIN
&&
.MARINE...
258 PM CDT
HIGH PRESSURE RIDGING ACROSS THE SOUTHERN GREAT LAKES WILL EXIT
THE AREA TO THE EAST THIS EVENING ALLOWING LOW PRESSURE OVER THE
CENTRAL PLAINS TO MOVE NORTHEAST INTO NORTHERN ILLINOIS BY
THURSDAY MORNING. MEANWHILE A WEAK COLD FRONT ACROSS THE NORTHERN
GREAT LAKES WILL SAG SOUTH AHEAD OF HIGH PRESSURE OVER ONTARIO AND
WASH OUT AS THE AFFOREMENTIONED LOW PRESSURE AREA MOVES INTO
ILLINOIS. AS THIS LOW MOVES EAST TO OHIO THURSDAY NIGHT ITS
ASSOCIATED COLD FRONT WILL DROP SOUTH AWAY FROM THE AREA ALLOWING
ANOTHER AREA OF WEAK HIGH PRESSURE TO BUILD ACROSS THE GREAT
LAKES. THIS HIGH WILL DRIFT EAST SUNDAY NIGHT INTO MONDAY ALLOWING
A SECONDARY COLD FRONT TO SAG SOUTH ACROSS THE NORTHERN GREAT
LAKES.
ED F
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ008-ILZ010-ILZ011-ILZ019-
ILZ021-ILZ032-ILZ039...7 PM WEDNESDAY TO 1 PM THURSDAY.
FLASH FLOOD WATCH...ILZ005-ILZ006-ILZ012-ILZ013-ILZ014-ILZ020-
ILZ022-ILZ023-ILZ033...MIDNIGHT THURSDAY TO 1 PM THURSDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-
INZ019...MIDNIGHT THURSDAY TO 1 PM THURSDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
258 PM CDT WED JUN 24 2015
.UPDATE...
1217 PM CDT
ALL INDICATIONS THIS MORNING CONTINUE TO POINT TO A CLASSIC TYPE
HEAVY RAIN EVENT ACROSS THE AREA. THE THREAT OF SEVERE THUNDERSTORMS
IS ALSO DECENT WITH THIS ACTIVITY AS WELL LATER THIS EVENING...AND
THIS PRIMARILY LOOKS TO BE IN THE FORM OF STRONG STRAIGHT LINE WINDS.
SHOWERS...WITH SOME EMBEDDED THUNDERSTORMS CONTINUE TO WEAKEN OVER
CENTRAL ILLINOIS AS THEY MOVE AWAY FROM THE BETTER FOCUS OF LAST
NIGHTS LOW LEVEL JET. SATELLITE IMAGERY CONTINUES TO INDICATE CLOUD
TOPS WARMING WITH THIS ACTIVITY...AND EVEN INDICATES SOME BREAKS IN
THE CLOUDS OVER FAR NORTHERN ILLINOIS. FARTHER WEST...HOWEVER...AN
AREA OF CONVECTION OVER EASTERN NE AND NEAR FAR WESTERN IOWA
CONTINUES TO MAINTAIN ITSELF. IT IS CERTAINLY POSSIBLE THAT THIS
ACTIVITY COULD CONTINUE TO MOVE EAST OVER IOWA INTO THIS
AFTERNOON...THEN SHIFT MORE SOUTHEAST ALONG THE MLCAPE GRADIENT. THIS
ACTIVITY...SHOULD IT MAINTAIN ITSELF THOUGH THE DAY...WOULD LIKELY
MISS MOST OF MY AREA...POSSIBLY ONLY IMPACTING MY SOUTHWESTERN
COUNTIES. SOME OF THE LATEST HRRR SOLUTIONS ARE IN LINE WITH THIS
THINKING.
OTHERWISE...THE FOCUS CONTINUES TO CENTER ON THIS EVENING THROUGH
THE OVERNIGHT FOR THE POTENTIAL OF VERY HEAVY RAIN AND FLASH
FLOODING. IT IS STILL ANTICIPATED THAT RENEWED CONVECTION WILL
DEVELOP LATER THIS AFTERNOON/EARLY THIS EVENING OVER PORTIONS OF
EASTERN IOWA INTO NORTHWESTERN ILLINOIS ALONG AND ON THE COOL SIDE
OF A NORTHWARD MOVING WARM FRONTAL BOUNDARY. THIS ACTIVITY WOULD
THEN LIKELY CONTINUE TO GROW UPSCALE AS RENEWED DEVELOPMENT
CONTINUES UPSTREAM THANKS TO A PERSISTENT SOUTHWESTERLY 40+ KT LOW
LEVEL JET CONTINUALLY REPLENISHING THE DEEP MOISTURE. THESE STORMS
WILL OCCUR WITHIN AROUND A 2 INCH PRECIPITABLE WATER
ENVIRONMENT...SO EXTREMELY HEAVY RAIN RATES WILL BE A HIGH CONCERN.
ALSO...WITH CONTINUAL UPSTREAM DEVELOPMENT LOOKING LIKELY...TRAINING
AND BACKBULDING OF CELLS COULD RESULT IN PROLONGED PERIODS OF THESE
VERY HEAVY RAIN RATES OCCURRING OVER THE SAME AREAS. AS SUCH...SOME
ISOLATED AREAS OVER THE AREA COULD EXPERIENCE 4-5+ INCH AMOUNTS OF
RAIN BEFORE THIS ACTIVITY ABATES LATER TONIGHT OR EARLY THURSDAY
MORNING. THERE ARE STILL SOME UNCERTAINTIES ON WHERE EXACTLY THE
HEAVIEST RAINFALL AMOUNTS WILL FALL. HOWEVER...WITH THE ACTIVITY
LIKELY TO MOVE EAST-SOUTHEAST WITH TIME...IT WOULD APPEAR THAT AREAS
ALONG AND SOUTH OF INTERSTATE 88 WOULD LIKELY STAND THE BEST
POTENTIAL TO EXPERIENCE RAINFALL AMOUNTS IN EXCESS OF 1 TO 2 INCHES.
WITHIN THESE TRAINING THUNDERSTORMS...THE KINEMATIC FIELDS OVER THE
AREA WILL ALSO LIKELY SUPPORT FORWARD PROPAGATING EAST-SOUTHEASTWARD
MOVING BOWING SEGMENTS OVER THE AREA. THEREFORE...STRONG DAMAGING
WINDS...PERHAPS IN EXCESS OF 70 MPH...WILL ALSO BE A THREAT WITH
THESE STORMS. A TORNADO OR TWO CAN ALSO NOT BE RULED OUT. HOWEVER...
THIS THREAT APPEARS TO BE THE HIGHEST OVER MY SOUTHEASTERN CWA THIS
EVENING IN CLOSER PROXIMATELY TO THE APPROACHING WARM FRONTAL
BOUNDARY.
KJB
&&
.SHORT TERM...
320 AM CDT
THROUGH WEDNESDAY NIGHT...
STRONG TO SEVERE THUNDERSTORMS COMPRISE THE PRIMARY FORECAST
CONCERNS FOR TODAY AND TONIGHT.
EARLY THIS MORNING...SURFACE HIGH PRESSURE IS CENTERED ACROSS
CENTRAL ILLINOIS PROVIDING MOSTLY CLEAR SKIES AND LIGHT WINDS
ACROSS NORTHERN ILLINOIS AND NORTHWEST INDIANA. FARTHER WEST...A
SURFACE TROUGH IS ANALYZED FROM NORTHERN KANSAS NE ACROSS THE MID-
MISSOURI VALLEY INTO CENTRAL IOWA. WATER VAPOR IMAGERY SHOWS A
SUBTLE/SHEARED WAVE EMBEDDED WITHIN THE MAINLY ZONAL FLOW ALOFT
MOVING ACROSS NORTHERN IOWA WHERE NOCTURNAL THUNDERSTORMS HAVE
DEVELOPED MAINLY FOCUSED ACROSS THE I-80 CORRIDOR IN IOWA. NAM/GFS
INITIALIZE ON THIS AREA OF THUNDERSTORMS AND KEEPS THE FORCING
FOCUSED TO THE WEST OF THE FORECAST AREA THROUGH MOST OF THE DAY
TODAY...ALONG WITH THE INSTABILITY. CANT RULE OUT SOME DECAYING
ELEVATED CONVECTION PROPAGATING INTO THE FORECAST AREA LATER
TODAY...HOWEVER EXPECT MOST OF THE CWA TO BE DRY THIS MORNING INTO
AT LEAST EARLY EVENING. WILL HAVE TO KEEP AN EYE ON HOW EARLY
MORNING CONVECTION IMPACTS THE MOVEMENT OF THE WARM FRONT THROUGH
THE DAY.
THIS EVENING...SURFACE TROUGH/WARM FRONT IS PROGGED TO SETTLE
ACROSS CENTRAL/NORTHERN IOWA INTO NORTHERN ILLINOIS THOUGH THERE
ARE NOTABLE DIFFERENCES AT THIS POINT AS TO EXACTLY HOW FAR NORTH.
VERY STRONG INSTABILITY IS EXPECTED TO DEVELOP SOUTH OF THE FRONT
WITH THUNDERSTORMS EXPECTED TO REDEVELOP/RESTRENGTHEN ACROSS IOWA
AFTERNOON INTO THE EVENING AS ANOTHER SHEARED VORT LOBE TRAVERSES
ACROSS THE REGION AND RIGHT ENTRANCE REGION TO THE LOW LEVEL JET
PROVIDES ADDITIONAL SYNOPTIC SCALE ASCENT. ASSUMING ATMOSPHERE
EFFECTIVELY RECOVERS FROM MORNING CONVECTION...FAVORABLE
SHEAR/INSTABILITY PROFILES...IMPRESSIVE CYCLONICALLY CURVED
HODOGRAPHS AND WHAT SHOULD BE SUFFICIENT FORCING TO OVERCOME ANY
CAPPING INVERSION WILL RESULT IN STRONG TO SEVERE THUNDERSTORMS
DEVELOPING WEST OF THE CWA...POSSIBLY IN A DISCRETE/SUPERCELL MODE
INITIALLY WITH THE FULL GAMUT OF SEVERE WEATHER POSSIBLE.
STRENGTHENING NOCTURNAL LOW LEVEL JET INTO THE EVENING WILL RESULT
IN STORMS MERGING INTO AN MCS AND PUSHING EAST INTO THE LOCAL
FORECAST AREA. AS THIS OCCURS...EXPECT THE PRIMARY SEVERE THREAT
TO CHANGE TO MORE OF A STRAIGHT LINE WIND DAMAGE AND FLOODING
THREAT. CORFIDI VECTORS DROP OFF TO AROUND 5 KT OR SO ON THE
SOUTHERN FLANK OF THE STORMS SO BACKBUILDING AND TRAINING
THUNDERSTORMS REMAIN A CONCERN. A FLASH FLOOD WATCH WAS ISSUED
YESTERDAY AND OPTED TO EXPAND NORTHWARD GIVEN THE TRENDS FROM THE
GFS/NAM...ALTHOUGH CONFIDENCE IS ADMITTEDLY A BIT LOWER ACROSS THE
NORTHERN TIER OF COUNTIES.
DEUBELBEISS
&&
.LONG TERM...
340 AM CDT
THURSDAY THROUGH TUESDAY...
THE UPPER LEVEL ZONAL FLOW FINALLY SHIFTS EAST LATE THIS WEEK AS AN
UPPER LEVEL TROUGH MOVES OVER THE REGION FRIDAY NIGHT. THE TROUGH
AXIS SHIFTS EAST SATURDAY WITH NORTHWEST FLOW SUNDAY. ANOTHER WEAKER
TROUGH IS POSSIBLE EARLY NEXT WEEK.
A SFC LOW WILL BE OVER NORTHERN IL AND NORTHWEST IN THURSDAY MORNING
AS A DYING MCS SLOWLY SHIFTS EAST. RAISED QPF AMOUNTS THURSDAY
MORNING AS THE DYING MCS SHOULD PRODUCE AT LEAST ANOTHER 0.35-0.5
INCHES OF RAIN SOUTH OF I-88. GUIDANCE DIFFERS ON HOW QUICKLY THE
MCS WILL EXIT THE REGION...BUT HAVE HIGH CONFIDENCE IN DRY
CONDITIONS THURSDAY NIGHT.
SADLY THERE IS A VERY SMALL BREAK BEFORE THE NEXT LOW PRESSURE
BRINGS MORE RAIN AND STORMS TO AREAS SOUTH OF I-80 FRIDAY. THE NEXT
LOW FORMS OVER THE SOUTHERN PLAINS THURSDAY NIGHT. IT THEN PASSES
OVER THE MID MISSISSIPPI VALLEY AND ALONG THE OHIO RIVER THROUGH
SATURDAY NIGHT. IT LOOKS LIKE THE MAJORITY OF PRECIP WILL FALL OVER
CENTRAL AND SOUTHERN IL...BUT KEPT A SLIGHT CHANCE TO CHANCE OF
THUNDERSTORMS SOUTH OF I-88. WE FINALLY SEE A DRY SPELL LATE THIS
WEEK AS THE LOW SHIFTS EAST AND HIGH PRESSURE SPREADS OVERHEAD.
THE NEXT CHANCE OF RAIN AND STORMS ARRIVES EARLY NEXT WEEK AS AN
UPPER LEVEL TROUGH SWINGS THROUGH. GUIDANCE DIFFERS ON HOW STRONG
THE TROUGH WILL BE AND HOW FAR SOUTH IT WILL TRAVEL...BUT HAVE
ENOUGH CONFIDENCE TO KEEP A CHANCE OF PRECIP IN THE FORECAST. WE
COULD SEE MULTIPLE VORTICITY STREAMERS SWING THROUGH AS THE TROUGH
SITS OVERHEAD SO KEPT A CHANCE OF PRECIP FROM SUNDAY NIGHT THROUGH
TUESDAY. DESPITE THE CONSTANT CHANCE OF RAIN...ONLY EXPECTING
PERIODS OF SHOWERS AND STORMS AT THIS POINT AND NOT COMPLETE
RAIN OUTS.
FOR TEMPS...THURSDAY LOOKS LIKE THE WARMEST DAY WITH HIGHS IN THE
UPPER 70S TO LOW 80S. LAKE COOLING WILL KEEP LAKEFRONT LOCATIONS IN
THE LOW 70S. COOLER AIR SINKS SOUTH THURSDAY NIGHT LEADING TO HIGH
TEMPS FRIDAY IN THE 70S WITH 60S ALONG THE LAKE. A SLOW WARM UP IS
EXPECTED WITH HIGHS BACK IN THE LOW 80S TUESDAY.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* CHANCE OF LAKE BREEZE DEVELOPMENT LATE THIS AFTERNOON.
* THUNDERSTORMS LIKELY OVERNIGHT TONIGHT...MVFR-IFR CIGS/VIS
LIKELY.
KREIN
//DISCUSSION...UPDATED 18Z...
AT THE SURFACE...A LARGE AREA OF HIGH PRESSURE IS CENTERED ALONG
THE IN/OH BORDER AS A MID LEVEL IMPULSE CROSSING THE MIDDLE
MISSISSIPPI VALLEY IS BRINGING AN AREA OF SHOWERS AND
THUNDERSTORMS FROM IOWA THROUGH CENTRAL IL TO CENTRAL IN. BASED
ON THE LATEST RADAR TRENDS...EXPECT THAT ANY PCPN AND TS SHOULD
REMAIN SOUTH OF OF THE TERMINALS EARLY THIS EVENING...THROUGH IT
COULD CLIP THE SOUTHERN PORTIONS OF THE C90 TRACON AREA. AS THE
CENTER OF THE HIGH CONTINUES TO SHIFT TO THE EAST...WINDS HAVE
BECOME SSWLY AND ARE INCREASING TO ARND 10KT. LATEST RADAR IMAGERY
AND COASTAL OBSERVATIONS SHOW A LAKE BREEZE MOVING ONSHORE NEAR
KUGN...BUT THERE IS LITTLE WESTWARD PROGRESSION AND DO NOT EXPECT
THAT THE BOUNDARY WILL REACH AS FAR WEST AS ORD/MDW.
RATHER...EXPECT THAT WINDS WILL GRADUALLY BACK TO MORE SELY
THROUGH THE AFTERNOON AND INTO THE EVENING IN RESPONSE TO THE
LARGER SCALE PRESSURE PATTERN WITH THE HIGH MOVING OFF TO THE EAST
AND LOW PRESSURE DEVELOPING OVER THE CNTRL PLAINS.
THE OTHER CONCERN FOR THE PERIOD WILL BE TIMING THE NEXT ROUND OF
THUNDERSTORMS TO IMPACT THE REGION. WHILE THE ONGOING PCPN SHOULD
REMAIN SOUTH OF THE TERMINALS...CONFIDENCE IS HIGHER THAT ANOTHER
ROUND OF THUNDERSTORMS WILL DEVELOP TONIGHT OVER THE CNTRL
PLAINS/IOWA AND THEN TRACK EASTWARD. LATEST GUIDANCE IS A LITTLE
FASTER THAN PREVIOUS MODEL RUNS AND SUGGESTS THAT TS COULD REACH
RFD BY ARND 03Z...AND THEN QUICKLY PUSHING TO THE EAST ACROSS THE
CHICAGO AREA TERMINALS. WHILE CONFIDENCE IS RELATIVELY HIGH IN TS
IMPACTING THE TERMINALS OVERNIGHT TONIGHT...TIMING AND DURATION IS
A LITTLE LOWER. ALSO...AS THE MAIN SFC LOW TRACKS ALONG A
DEVELOPING WARM FRONT EXPECTED TO SET THROUGH CNTRL OR NRN IL/IN
AND WITH UPPER LEVEL FLOW SETTING UP TO BE PARALLEL TO THE SFC
FRONT...AN EXTENDED PERIOD OF TSRA IMPACTING THE TERMINALS IS
QUITE POSSIBLE OVERNIGHT AND POSSIBLY EVEN INTO TOMORROW MORNING.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM TO HIGH CONFIDENCE IN GENERAL WIND TRENDS.
* MEDIUM CONFIDENCE IN LAKE BREEZE DETAILS...AND THAT THE LAKE
BREEZE BOUNDARY WILL REMAIN EAST OF THE TERMINALS.
* MEDIUM TO HIGH CONFIDENCE IN TS IMPACTING THE TERMINALS THIS
EVENING AND TONIGHT...LOWER CONFIDENCE IN EXACT TIMING AND
DURATION.
* MEDIUM CONFIDENCE IN A PERIOD OF MVFR-IFR CIGS/VIS WITH THE
TSRA/PCPN OVERNIGHT TONIGHT AND INTO TOMORROW MORNING.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR. WX NIL. NELY WINDS.
FRIDAY...VFR. WX NIL. NELY WINDS.
SATURDAY...VFR. WX NIL. NELY WINDS BACKING NWLY LATE.
SUNDAY...CHANCE TSRA. MVFR POSSIBLE. NWLY WINDS BACKING SWLY.
MONDAY...CHANCE TSRA. MVFR POSSIBLE. SWLY WINDS VEERING NWLY
TUESDAY...SLIGHT CHANCE TSRA. VRBL WINDS.
KREIN
&&
.MARINE...
258 PM CDT
HIGH PRESSURE RIDGING ACROSS THE SOUTHERN GREAT LAKES WILL EXIT
THE AREA TO THE EAST THIS EVENING ALLOWING LOW PRESSURE OVER THE
CENTRAL PLAINS TO MOVE NORTHEAST INTO NORTHERN ILLINOIS BY
THURSDAY MORNING. MEANWHILE A WEAK COLD FRONT ACROSS THE NORTHERN
GREAT LAKES WILL SAG SOUTH AHEAD OF HIGH PRESSURE OVER ONTARIO AND
WASH OUT AS THE AFFOREMENTIONED LOW PRESSURE AREA MOVES INTO
ILLINOIS. AS THIS LOW MOVES EAST TO OHIO THURSDAY NIGHT ITS
ASSOCIATED COLD FRONT WILL DROP SOUTH AWAY FROM THE AREA ALLOWING
ANOTHER AREA OF WEAK HIGH PRESSURE TO BUILD ACROSS THE GREAT
LAKES. THIS HIGH WILL DRIFT EAST SUNDAY NIGHT INTO MONDAY ALLOWING
A SECONDARY COLD FRONT TO SAG SOUTH ACROSS THE NORTHERN GREAT
LAKES.
ED F
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ008-ILZ010-ILZ011-ILZ019-
ILZ021-ILZ032-ILZ039...7 PM WEDNESDAY TO 1 PM THURSDAY.
FLASH FLOOD WATCH...ILZ005-ILZ006-ILZ012-ILZ013-ILZ014-ILZ020-
ILZ022-ILZ023-ILZ033...MIDNIGHT THURSDAY TO 1 PM THURSDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-
INZ019...MIDNIGHT THURSDAY TO 1 PM THURSDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
235 PM CDT WED JUN 24 2015
.UPDATE...
1217 PM CDT
ALL INDICATIONS THIS MORNING CONTINUE TO POINT TO A CLASSIC TYPE
HEAVY RAIN EVENT ACROSS THE AREA. THE THREAT OF SEVERE THUNDERSTORMS
IS ALSO DECENT WITH THIS ACTIVITY AS WELL LATER THIS EVENING...AND
THIS PRIMARILY LOOKS TO BE IN THE FORM OF STRONG STRAIGHT LINE WINDS.
SHOWERS...WITH SOME EMBEDDED THUNDERSTORMS CONTINUE TO WEAKEN OVER
CENTRAL ILLINOIS AS THEY MOVE AWAY FROM THE BETTER FOCUS OF LAST
NIGHTS LOW LEVEL JET. SATELLITE IMAGERY CONTINUES TO INDICATE CLOUD
TOPS WARMING WITH THIS ACTIVITY...AND EVEN INDICATES SOME BREAKS IN
THE CLOUDS OVER FAR NORTHERN ILLINOIS. FARTHER WEST...HOWEVER...AN
AREA OF CONVECTION OVER EASTERN NE AND NEAR FAR WESTERN IOWA
CONTINUES TO MAINTAIN ITSELF. IT IS CERTAINLY POSSIBLE THAT THIS
ACTIVITY COULD CONTINUE TO MOVE EAST OVER IOWA INTO THIS
AFTERNOON...THEN SHIFT MORE SOUTHEAST ALONG THE MLCAPE GRADIENT. THIS
ACTIVITY...SHOULD IT MAINTAIN ITSELF THOUGH THE DAY...WOULD LIKELY
MISS MOST OF MY AREA...POSSIBLY ONLY IMPACTING MY SOUTHWESTERN
COUNTIES. SOME OF THE LATEST HRRR SOLUTIONS ARE IN LINE WITH THIS
THINKING.
OTHERWISE...THE FOCUS CONTINUES TO CENTER ON THIS EVENING THROUGH
THE OVERNIGHT FOR THE POTENTIAL OF VERY HEAVY RAIN AND FLASH
FLOODING. IT IS STILL ANTICIPATED THAT RENEWED CONVECTION WILL
DEVELOP LATER THIS AFTERNOON/EARLY THIS EVENING OVER PORTIONS OF
EASTERN IOWA INTO NORTHWESTERN ILLINOIS ALONG AND ON THE COOL SIDE
OF A NORTHWARD MOVING WARM FRONTAL BOUNDARY. THIS ACTIVITY WOULD
THEN LIKELY CONTINUE TO GROW UPSCALE AS RENEWED DEVELOPMENT
CONTINUES UPSTREAM THANKS TO A PERSISTENT SOUTHWESTERLY 40+ KT LOW
LEVEL JET CONTINUALLY REPLENISHING THE DEEP MOISTURE. THESE STORMS
WILL OCCUR WITHIN AROUND A 2 INCH PRECIPITABLE WATER
ENVIRONMENT...SO EXTREMELY HEAVY RAIN RATES WILL BE A HIGH CONCERN.
ALSO...WITH CONTINUAL UPSTREAM DEVELOPMENT LOOKING LIKELY...TRAINING
AND BACKBULDING OF CELLS COULD RESULT IN PROLONGED PERIODS OF THESE
VERY HEAVY RAIN RATES OCCURRING OVER THE SAME AREAS. AS SUCH...SOME
ISOLATED AREAS OVER THE AREA COULD EXPERIENCE 4-5+ INCH AMOUNTS OF
RAIN BEFORE THIS ACTIVITY ABATES LATER TONIGHT OR EARLY THURSDAY
MORNING. THERE ARE STILL SOME UNCERTAINTIES ON WHERE EXACTLY THE
HEAVIEST RAINFALL AMOUNTS WILL FALL. HOWEVER...WITH THE ACTIVITY
LIKELY TO MOVE EAST-SOUTHEAST WITH TIME...IT WOULD APPEAR THAT AREAS
ALONG AND SOUTH OF INTERSTATE 88 WOULD LIKELY STAND THE BEST
POTENTIAL TO EXPERIENCE RAINFALL AMOUNTS IN EXCESS OF 1 TO 2 INCHES.
WITHIN THESE TRAINING THUNDERSTORMS...THE KINEMATIC FIELDS OVER THE
AREA WILL ALSO LIKELY SUPPORT FORWARD PROPAGATING EAST-SOUTHEASTWARD
MOVING BOWING SEGMENTS OVER THE AREA. THEREFORE...STRONG DAMAGING
WINDS...PERHAPS IN EXCESS OF 70 MPH...WILL ALSO BE A THREAT WITH
THESE STORMS. A TORNADO OR TWO CAN ALSO NOT BE RULED OUT. HOWEVER...
THIS THREAT APPEARS TO BE THE HIGHEST OVER MY SOUTHEASTERN CWA THIS
EVENING IN CLOSER PROXIMATELY TO THE APPROACHING WARM FRONTAL
BOUNDARY.
KJB
&&
.SHORT TERM...
320 AM CDT
THROUGH WEDNESDAY NIGHT...
STRONG TO SEVERE THUNDERSTORMS COMPRISE THE PRIMARY FORECAST
CONCERNS FOR TODAY AND TONIGHT.
EARLY THIS MORNING...SURFACE HIGH PRESSURE IS CENTERED ACROSS
CENTRAL ILLINOIS PROVIDING MOSTLY CLEAR SKIES AND LIGHT WINDS
ACROSS NORTHERN ILLINOIS AND NORTHWEST INDIANA. FARTHER WEST...A
SURFACE TROUGH IS ANALYZED FROM NORTHERN KANSAS NE ACROSS THE MID-
MISSOURI VALLEY INTO CENTRAL IOWA. WATER VAPOR IMAGERY SHOWS A
SUBTLE/SHEARED WAVE EMBEDDED WITHIN THE MAINLY ZONAL FLOW ALOFT
MOVING ACROSS NORTHERN IOWA WHERE NOCTURNAL THUNDERSTORMS HAVE
DEVELOPED MAINLY FOCUSED ACROSS THE I-80 CORRIDOR IN IOWA. NAM/GFS
INITIALIZE ON THIS AREA OF THUNDERSTORMS AND KEEPS THE FORCING
FOCUSED TO THE WEST OF THE FORECAST AREA THROUGH MOST OF THE DAY
TODAY...ALONG WITH THE INSTABILITY. CANT RULE OUT SOME DECAYING
ELEVATED CONVECTION PROPAGATING INTO THE FORECAST AREA LATER
TODAY...HOWEVER EXPECT MOST OF THE CWA TO BE DRY THIS MORNING INTO
AT LEAST EARLY EVENING. WILL HAVE TO KEEP AN EYE ON HOW EARLY
MORNING CONVECTION IMPACTS THE MOVEMENT OF THE WARM FRONT THROUGH
THE DAY.
THIS EVENING...SURFACE TROUGH/WARM FRONT IS PROGGED TO SETTLE
ACROSS CENTRAL/NORTHERN IOWA INTO NORTHERN ILLINOIS THOUGH THERE
ARE NOTABLE DIFFERENCES AT THIS POINT AS TO EXACTLY HOW FAR NORTH.
VERY STRONG INSTABILITY IS EXPECTED TO DEVELOP SOUTH OF THE FRONT
WITH THUNDERSTORMS EXPECTED TO REDEVELOP/RESTRENGTHEN ACROSS IOWA
AFTERNOON INTO THE EVENING AS ANOTHER SHEARED VORT LOBE TRAVERSES
ACROSS THE REGION AND RIGHT ENTRANCE REGION TO THE LOW LEVEL JET
PROVIDES ADDITIONAL SYNOPTIC SCALE ASCENT. ASSUMING ATMOSPHERE
EFFECTIVELY RECOVERS FROM MORNING CONVECTION...FAVORABLE
SHEAR/INSTABILITY PROFILES...IMPRESSIVE CYCLONICALLY CURVED
HODOGRAPHS AND WHAT SHOULD BE SUFFICIENT FORCING TO OVERCOME ANY
CAPPING INVERSION WILL RESULT IN STRONG TO SEVERE THUNDERSTORMS
DEVELOPING WEST OF THE CWA...POSSIBLY IN A DISCRETE/SUPERCELL MODE
INITIALLY WITH THE FULL GAMUT OF SEVERE WEATHER POSSIBLE.
STRENGTHENING NOCTURNAL LOW LEVEL JET INTO THE EVENING WILL RESULT
IN STORMS MERGING INTO AN MCS AND PUSHING EAST INTO THE LOCAL
FORECAST AREA. AS THIS OCCURS...EXPECT THE PRIMARY SEVERE THREAT
TO CHANGE TO MORE OF A STRAIGHT LINE WIND DAMAGE AND FLOODING
THREAT. CORFIDI VECTORS DROP OFF TO AROUND 5 KT OR SO ON THE
SOUTHERN FLANK OF THE STORMS SO BACKBUILDING AND TRAINING
THUNDERSTORMS REMAIN A CONCERN. A FLASH FLOOD WATCH WAS ISSUED
YESTERDAY AND OPTED TO EXPAND NORTHWARD GIVEN THE TRENDS FROM THE
GFS/NAM...ALTHOUGH CONFIDENCE IS ADMITTEDLY A BIT LOWER ACROSS THE
NORTHERN TIER OF COUNTIES.
DEUBELBEISS
&&
.LONG TERM...
340 AM CDT
THURSDAY THROUGH TUESDAY...
THE UPPER LEVEL ZONAL FLOW FINALLY SHIFTS EAST LATE THIS WEEK AS AN
UPPER LEVEL TROUGH MOVES OVER THE REGION FRIDAY NIGHT. THE TROUGH
AXIS SHIFTS EAST SATURDAY WITH NORTHWEST FLOW SUNDAY. ANOTHER WEAKER
TROUGH IS POSSIBLE EARLY NEXT WEEK.
A SFC LOW WILL BE OVER NORTHERN IL AND NORTHWEST IN THURSDAY MORNING
AS A DYING MCS SLOWLY SHIFTS EAST. RAISED QPF AMOUNTS THURSDAY
MORNING AS THE DYING MCS SHOULD PRODUCE AT LEAST ANOTHER 0.35-0.5
INCHES OF RAIN SOUTH OF I-88. GUIDANCE DIFFERS ON HOW QUICKLY THE
MCS WILL EXIT THE REGION...BUT HAVE HIGH CONFIDENCE IN DRY
CONDITIONS THURSDAY NIGHT.
SADLY THERE IS A VERY SMALL BREAK BEFORE THE NEXT LOW PRESSURE
BRINGS MORE RAIN AND STORMS TO AREAS SOUTH OF I-80 FRIDAY. THE NEXT
LOW FORMS OVER THE SOUTHERN PLAINS THURSDAY NIGHT. IT THEN PASSES
OVER THE MID MISSISSIPPI VALLEY AND ALONG THE OHIO RIVER THROUGH
SATURDAY NIGHT. IT LOOKS LIKE THE MAJORITY OF PRECIP WILL FALL OVER
CENTRAL AND SOUTHERN IL...BUT KEPT A SLIGHT CHANCE TO CHANCE OF
THUNDERSTORMS SOUTH OF I-88. WE FINALLY SEE A DRY SPELL LATE THIS
WEEK AS THE LOW SHIFTS EAST AND HIGH PRESSURE SPREADS OVERHEAD.
THE NEXT CHANCE OF RAIN AND STORMS ARRIVES EARLY NEXT WEEK AS AN
UPPER LEVEL TROUGH SWINGS THROUGH. GUIDANCE DIFFERS ON HOW STRONG
THE TROUGH WILL BE AND HOW FAR SOUTH IT WILL TRAVEL...BUT HAVE
ENOUGH CONFIDENCE TO KEEP A CHANCE OF PRECIP IN THE FORECAST. WE
COULD SEE MULTIPLE VORTICITY STREAMERS SWING THROUGH AS THE TROUGH
SITS OVERHEAD SO KEPT A CHANCE OF PRECIP FROM SUNDAY NIGHT THROUGH
TUESDAY. DESPITE THE CONSTANT CHANCE OF RAIN...ONLY EXPECTING
PERIODS OF SHOWERS AND STORMS AT THIS POINT AND NOT COMPLETE
RAIN OUTS.
FOR TEMPS...THURSDAY LOOKS LIKE THE WARMEST DAY WITH HIGHS IN THE
UPPER 70S TO LOW 80S. LAKE COOLING WILL KEEP LAKEFRONT LOCATIONS IN
THE LOW 70S. COOLER AIR SINKS SOUTH THURSDAY NIGHT LEADING TO HIGH
TEMPS FRIDAY IN THE 70S WITH 60S ALONG THE LAKE. A SLOW WARM UP IS
EXPECTED WITH HIGHS BACK IN THE LOW 80S TUESDAY.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* CHANCE OF LAKE BREEZE DEVELOPMENT LATE THIS AFTERNOON.
* THUNDERSTORMS LIKELY OVERNIGHT TONIGHT...MVFR-IFR CIGS/VIS
LIKELY.
KREIN
//DISCUSSION...UPDATED 18Z...
AT THE SURFACE...A LARGE AREA OF HIGH PRESSURE IS CENTERED ALONG
THE IN/OH BORDER AS A MID LEVEL IMPULSE CROSSING THE MIDDLE
MISSISSIPPI VALLEY IS BRINGING AN AREA OF SHOWERS AND
THUNDERSTORMS FROM IOWA THROUGH CENTRAL IL TO CENTRAL IN. BASED
ON THE LATEST RADAR TRENDS...EXPECT THAT ANY PCPN AND TS SHOULD
REMAIN SOUTH OF OF THE TERMINALS EARLY THIS EVENING...THROUGH IT
COULD CLIP THE SOUTHERN PORTIONS OF THE C90 TRACON AREA. AS THE
CENTER OF THE HIGH CONTINUES TO SHIFT TO THE EAST...WINDS HAVE
BECOME SSWLY AND ARE INCREASING TO ARND 10KT. LATEST RADAR IMAGERY
AND COASTAL OBSERVATIONS SHOW A LAKE BREEZE MOVING ONSHORE NEAR
KUGN...BUT THERE IS LITTLE WESTWARD PROGRESSION AND DO NOT EXPECT
THAT THE BOUNDARY WILL REACH AS FAR WEST AS ORD/MDW.
RATHER...EXPECT THAT WINDS WILL GRADUALLY BACK TO MORE SELY
THROUGH THE AFTERNOON AND INTO THE EVENING IN RESPONSE TO THE
LARGER SCALE PRESSURE PATTERN WITH THE HIGH MOVING OFF TO THE EAST
AND LOW PRESSURE DEVELOPING OVER THE CNTRL PLAINS.
THE OTHER CONCERN FOR THE PERIOD WILL BE TIMING THE NEXT ROUND OF
THUNDERSTORMS TO IMPACT THE REGION. WHILE THE ONGOING PCPN SHOULD
REMAIN SOUTH OF THE TERMINALS...CONFIDENCE IS HIGHER THAT ANOTHER
ROUND OF THUNDERSTORMS WILL DEVELOP TONIGHT OVER THE CNTRL
PLAINS/IOWA AND THEN TRACK EASTWARD. LATEST GUIDANCE IS A LITTLE
FASTER THAN PREVIOUS MODEL RUNS AND SUGGESTS THAT TS COULD REACH
RFD BY ARND 03Z...AND THEN QUICKLY PUSHING TO THE EAST ACROSS THE
CHICAGO AREA TERMINALS. WHILE CONFIDENCE IS RELATIVELY HIGH IN TS
IMPACTING THE TERMINALS OVERNIGHT TONIGHT...TIMING AND DURATION IS
A LITTLE LOWER. ALSO...AS THE MAIN SFC LOW TRACKS ALONG A
DEVELOPING WARM FRONT EXPECTED TO SET THROUGH CNTRL OR NRN IL/IN
AND WITH UPPER LEVEL FLOW SETTING UP TO BE PARALLEL TO THE SFC
FRONT...AN EXTENDED PERIOD OF TSRA IMPACTING THE TERMINALS IS
QUITE POSSIBLE OVERNIGHT AND POSSIBLY EVEN INTO TOMORROW MORNING.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM TO HIGH CONFIDENCE IN GENERAL WIND TRENDS.
* MEDIUM CONFIDENCE IN LAKE BREEZE DETAILS...AND THAT THE LAKE
BREEZE BOUNDARY WILL REMAIN EAST OF THE TERMINALS.
* MEDIUM TO HIGH CONFIDENCE IN TS IMPACTING THE TERMINALS THIS
EVENING AND TONIGHT...LOWER CONFIDENCE IN EXACT TIMING AND
DURATION.
* MEDIUM CONFIDENCE IN A PERIOD OF MVFR-IFR CIGS/VIS WITH THE
TSRA/PCPN OVERNIGHT TONIGHT AND INTO TOMORROW MORNING.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR. WX NIL. NELY WINDS.
FRIDAY...VFR. WX NIL. NELY WINDS.
SATURDAY...VFR. WX NIL. NELY WINDS BACKING NWLY LATE.
SUNDAY...CHANCE TSRA. MVFR POSSIBLE. NWLY WINDS BACKING SWLY.
MONDAY...CHANCE TSRA. MVFR POSSIBLE. SWLY WINDS VEERING NWLY
TUESDAY...SLIGHT CHANCE TSRA. VRBL WINDS.
KREIN
&&
.MARINE...
410 AM CDT
HIGH PRESSURE IS OVER THE REGION WITH LIGHT SOUTHWEST WINDS. WINDS
REMAIN LIGHT AND BECOME EAST THURSDAY MORNING AS A LOW PRESSURE
SYSTEM MOVES OVER THE SOUTHERN END OF THE LAKE. GUIDANCE DIFFERS ON
HOW STRONG THE LOW WILL BE SO WIND SPEEDS COULD BE STRONGER OVER THE
SOUTHERN END OF THE LAKE IF THE LOW IS STRONGER. THE LOW SHIFTS
EAST AND ANOTHER LOW PASSES WELL SOUTH OF THE LAKE OVER THE OHIO
RIVER LATE THIS WEEK. PERSISTENT NORTH TO NORTHEAST WINDS AT 20KT OR
LESS ARE EXPECTED THROUGH SATURDAY NIGHT. HIGH PRESSURE SPREADS
SOUTH OF THE LAKE WHILE A LOW SPREADS OVER THE LAKE SUNDAY NIGHT
WITH WINDS BCMG SOUTH SUNDAY EVENING AND REMAINING SOUTH TO
SOUTHWEST THROUGH MONDAY NIGHT.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039...7 PM WEDNESDAY TO 1 PM
THURSDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019...7 PM
WEDNESDAY TO 1 PM THURSDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1238 PM CDT WED JUN 24 2015
.UPDATE...
1217 PM CDT
ALL INDICATIONS THIS MORNING CONTINUE TO POINT TO A CLASSIC TYPE
HEAVY RAIN EVENT ACROSS THE AREA. THE THREAT OF SEVERE THUNDERSTORMS
IS ALSO DECENT WITH THIS ACTIVITY AS WELL LATER THIS EVENING...AND
THIS PRIMARILY LOOKS TO BE IN THE FORM OF STRONG STRAIGHT LINE WINDS.
SHOWERS...WITH SOME EMBEDDED THUNDERSTORMS CONTINUE TO WEAKEN OVER
CENTRAL ILLINOIS AS THEY MOVE AWAY FROM THE BETTER FOCUS OF LAST
NIGHTS LOW LEVEL JET. SATELLITE IMAGERY CONTINUES TO INDICATE CLOUD
TOPS WARMING WITH THIS ACTIVITY...AND EVEN INDICATES SOME BREAKS IN
THE CLOUDS OVER FAR NORTHERN ILLINOIS. FARTHER WEST...HOWEVER...AN
AREA OF CONVECTION OVER EASTERN NE AND NEAR FAR WESTERN IOWA
CONTINUES TO MAINTAIN ITSELF. IT IS CERTAINLY POSSIBLE THAT THIS
ACTIVITY COULD CONTINUE TO MOVE EAST OVER IOWA INTO THIS
AFTERNOON...THEN SHIFT MORE SOUTHEAST ALONG THE MLCAPE GRADIENT. THIS
ACTIVITY...SHOULD IT MAINTAIN ITSELF THOUGH THE DAY...WOULD LIKELY
MISS MOST OF MY AREA...POSSIBLY ONLY IMPACTING MY SOUTHWESTERN
COUNTIES. SOME OF THE LATEST HRRR SOLUTIONS ARE IN LINE WITH THIS
THINKING.
OTHERWISE...THE FOCUS CONTINUES TO CENTER ON THIS EVENING THROUGH
THE OVERNIGHT FOR THE POTENTIAL OF VERY HEAVY RAIN AND FLASH
FLOODING. IT IS STILL ANTICIPATED THAT RENEWED CONVECTION WILL
DEVELOP LATER THIS AFTERNOON/EARLY THIS EVENING OVER PORTIONS OF
EASTERN IOWA INTO NORTHWESTERN ILLINOIS ALONG AND ON THE COOL SIDE
OF A NORTHWARD MOVING WARM FRONTAL BOUNDARY. THIS ACTIVITY WOULD
THEN LIKELY CONTINUE TO GROW UPSCALE AS RENEWED DEVELOPMENT
CONTINUES UPSTREAM THANKS TO A PERSISTENT SOUTHWESTERLY 40+ KT LOW
LEVEL JET CONTINUALLY REPLENISHING THE DEEP MOISTURE. THESE STORMS
WILL OCCUR WITHIN AROUND A 2 INCH PRECIPITABLE WATER
ENVIRONMENT...SO EXTREMELY HEAVY RAIN RATES WILL BE A HIGH CONCERN.
ALSO...WITH CONTINUAL UPSTREAM DEVELOPMENT LOOKING LIKELY...TRAINING
AND BACKBULDING OF CELLS COULD RESULT IN PROLONGED PERIODS OF THESE
VERY HEAVY RAIN RATES OCCURRING OVER THE SAME AREAS. AS SUCH...SOME
ISOLATED AREAS OVER THE AREA COULD EXPERIENCE 4-5+ INCH AMOUNTS OF
RAIN BEFORE THIS ACTIVITY ABATES LATER TONIGHT OR EARLY THURSDAY
MORNING. THERE ARE STILL SOME UNCERTAINTIES ON WHERE EXACTLY THE
HEAVIEST RAINFALL AMOUNTS WILL FALL. HOWEVER...WITH THE ACTIVITY
LIKELY TO MOVE EAST-SOUTHEAST WITH TIME...IT WOULD APPEAR THAT AREAS
ALONG AND SOUTH OF INTERSTATE 88 WOULD LIKELY STAND THE BEST
POTENTIAL TO EXPERIENCE RAINFALL AMOUNTS IN EXCESS OF 1 TO 2 INCHES.
WITHIN THESE TRAINING THUNDERSTORMS...THE KINEMATIC FIELDS OVER THE
AREA WILL ALSO LIKELY SUPPORT FORWARD PROPAGATING EAST-SOUTHEASTWARD
MOVING BOWING SEGMENTS OVER THE AREA. THEREFORE...STRONG DAMAGING
WINDS...PERHAPS IN EXCESS OF 70 MPH...WILL ALSO BE A THREAT WITH
THESE STORMS. A TORNADO OR TWO CAN ALSO NOT BE RULED OUT. HOWEVER...
THIS THREAT APPEARS TO BE THE HIGHEST OVER MY SOUTHEASTERN CWA THIS
EVENING IN CLOSER PROXIMATELY TO THE APPROACHING WARM FRONTAL
BOUNDARY.
KJB
&&
.SHORT TERM...
320 AM CDT
THROUGH WEDNESDAY NIGHT...
STRONG TO SEVERE THUNDERSTORMS COMPRISE THE PRIMARY FORECAST
CONCERNS FOR TODAY AND TONIGHT.
EARLY THIS MORNING...SURFACE HIGH PRESSURE IS CENTERED ACROSS
CENTRAL ILLINOIS PROVIDING MOSTLY CLEAR SKIES AND LIGHT WINDS
ACROSS NORTHERN ILLINOIS AND NORTHWEST INDIANA. FARTHER WEST...A
SURFACE TROUGH IS ANALYZED FROM NORTHERN KANSAS NE ACROSS THE MID-
MISSOURI VALLEY INTO CENTRAL IOWA. WATER VAPOR IMAGERY SHOWS A
SUBTLE/SHEARED WAVE EMBEDDED WITHIN THE MAINLY ZONAL FLOW ALOFT
MOVING ACROSS NORTHERN IOWA WHERE NOCTURNAL THUNDERSTORMS HAVE
DEVELOPED MAINLY FOCUSED ACROSS THE I-80 CORRIDOR IN IOWA. NAM/GFS
INITIALIZE ON THIS AREA OF THUNDERSTORMS AND KEEPS THE FORCING
FOCUSED TO THE WEST OF THE FORECAST AREA THROUGH MOST OF THE DAY
TODAY...ALONG WITH THE INSTABILITY. CANT RULE OUT SOME DECAYING
ELEVATED CONVECTION PROPAGATING INTO THE FORECAST AREA LATER
TODAY...HOWEVER EXPECT MOST OF THE CWA TO BE DRY THIS MORNING INTO
AT LEAST EARLY EVENING. WILL HAVE TO KEEP AN EYE ON HOW EARLY
MORNING CONVECTION IMPACTS THE MOVEMENT OF THE WARM FRONT THROUGH
THE DAY.
THIS EVENING...SURFACE TROUGH/WARM FRONT IS PROGGED TO SETTLE
ACROSS CENTRAL/NORTHERN IOWA INTO NORTHERN ILLINOIS THOUGH THERE
ARE NOTABLE DIFFERENCES AT THIS POINT AS TO EXACTLY HOW FAR NORTH.
VERY STRONG INSTABILITY IS EXPECTED TO DEVELOP SOUTH OF THE FRONT
WITH THUNDERSTORMS EXPECTED TO REDEVELOP/RESTRENGTHEN ACROSS IOWA
AFTERNOON INTO THE EVENING AS ANOTHER SHEARED VORT LOBE TRAVERSES
ACROSS THE REGION AND RIGHT ENTRANCE REGION TO THE LOW LEVEL JET
PROVIDES ADDITIONAL SYNOPTIC SCALE ASCENT. ASSUMING ATMOSPHERE
EFFECTIVELY RECOVERS FROM MORNING CONVECTION...FAVORABLE
SHEAR/INSTABILITY PROFILES...IMPRESSIVE CYCLONICALLY CURVED
HODOGRAPHS AND WHAT SHOULD BE SUFFICIENT FORCING TO OVERCOME ANY
CAPPING INVERSION WILL RESULT IN STRONG TO SEVERE THUNDERSTORMS
DEVELOPING WEST OF THE CWA...POSSIBLY IN A DISCRETE/SUPERCELL MODE
INITIALLY WITH THE FULL GAMUT OF SEVERE WEATHER POSSIBLE.
STRENGTHENING NOCTURNAL LOW LEVEL JET INTO THE EVENING WILL RESULT
IN STORMS MERGING INTO AN MCS AND PUSHING EAST INTO THE LOCAL
FORECAST AREA. AS THIS OCCURS...EXPECT THE PRIMARY SEVERE THREAT
TO CHANGE TO MORE OF A STRAIGHT LINE WIND DAMAGE AND FLOODING
THREAT. CORFIDI VECTORS DROP OFF TO AROUND 5 KT OR SO ON THE
SOUTHERN FLANK OF THE STORMS SO BACKBUILDING AND TRAINING
THUNDERSTORMS REMAIN A CONCERN. A FLASH FLOOD WATCH WAS ISSUED
YESTERDAY AND OPTED TO EXPAND NORTHWARD GIVEN THE TRENDS FROM THE
GFS/NAM...ALTHOUGH CONFIDENCE IS ADMITTEDLY A BIT LOWER ACROSS THE
NORTHERN TIER OF COUNTIES.
DEUBELBEISS
&&
.LONG TERM...
340 AM CDT
THURSDAY THROUGH TUESDAY...
THE UPPER LEVEL ZONAL FLOW FINALLY SHIFTS EAST LATE THIS WEEK AS AN
UPPER LEVEL TROUGH MOVES OVER THE REGION FRIDAY NIGHT. THE TROUGH
AXIS SHIFTS EAST SATURDAY WITH NORTHWEST FLOW SUNDAY. ANOTHER WEAKER
TROUGH IS POSSIBLE EARLY NEXT WEEK.
A SFC LOW WILL BE OVER NORTHERN IL AND NORTHWEST IN THURSDAY MORNING
AS A DYING MCS SLOWLY SHIFTS EAST. RAISED QPF AMOUNTS THURSDAY
MORNING AS THE DYING MCS SHOULD PRODUCE AT LEAST ANOTHER 0.35-0.5
INCHES OF RAIN SOUTH OF I-88. GUIDANCE DIFFERS ON HOW QUICKLY THE
MCS WILL EXIT THE REGION...BUT HAVE HIGH CONFIDENCE IN DRY
CONDITIONS THURSDAY NIGHT.
SADLY THERE IS A VERY SMALL BREAK BEFORE THE NEXT LOW PRESSURE
BRINGS MORE RAIN AND STORMS TO AREAS SOUTH OF I-80 FRIDAY. THE NEXT
LOW FORMS OVER THE SOUTHERN PLAINS THURSDAY NIGHT. IT THEN PASSES
OVER THE MID MISSISSIPPI VALLEY AND ALONG THE OHIO RIVER THROUGH
SATURDAY NIGHT. IT LOOKS LIKE THE MAJORITY OF PRECIP WILL FALL OVER
CENTRAL AND SOUTHERN IL...BUT KEPT A SLIGHT CHANCE TO CHANCE OF
THUNDERSTORMS SOUTH OF I-88. WE FINALLY SEE A DRY SPELL LATE THIS
WEEK AS THE LOW SHIFTS EAST AND HIGH PRESSURE SPREADS OVERHEAD.
THE NEXT CHANCE OF RAIN AND STORMS ARRIVES EARLY NEXT WEEK AS AN
UPPER LEVEL TROUGH SWINGS THROUGH. GUIDANCE DIFFERS ON HOW STRONG
THE TROUGH WILL BE AND HOW FAR SOUTH IT WILL TRAVEL...BUT HAVE
ENOUGH CONFIDENCE TO KEEP A CHANCE OF PRECIP IN THE FORECAST. WE
COULD SEE MULTIPLE VORTICITY STREAMERS SWING THROUGH AS THE TROUGH
SITS OVERHEAD SO KEPT A CHANCE OF PRECIP FROM SUNDAY NIGHT THROUGH
TUESDAY. DESPITE THE CONSTANT CHANCE OF RAIN...ONLY EXPECTING
PERIODS OF SHOWERS AND STORMS AT THIS POINT AND NOT COMPLETE
RAIN OUTS.
FOR TEMPS...THURSDAY LOOKS LIKE THE WARMEST DAY WITH HIGHS IN THE
UPPER 70S TO LOW 80S. LAKE COOLING WILL KEEP LAKEFRONT LOCATIONS IN
THE LOW 70S. COOLER AIR SINKS SOUTH THURSDAY NIGHT LEADING TO HIGH
TEMPS FRIDAY IN THE 70S WITH 60S ALONG THE LAKE. A SLOW WARM UP IS
EXPECTED WITH HIGHS BACK IN THE LOW 80S TUESDAY.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* CHANCE OF LAKE BREEZE DEVELOPMENT LATE THIS AFTERNOON.
* THUNDERSTORMS LIKELY OVERNIGHT TONIGHT...MVFR-IFR CIGS/VIS
LIKELY.
KREIN
//DISCUSSION...UPDATED 18Z...
AT THE SURFACE...A LARGE AREA OF HIGH PRESSURE IS CENTERED ALONG
THE IN/OH BORDER AS A MID LEVEL IMPULSE CROSSING THE MIDDLE
MISSISSIPPI VALLEY IS BRINGING AN AREA OF SHOWERS AND
THUNDERSTORMS FROM IOWA THROUGH CENTRAL IL TO CENTRAL IN. BASED
ON THE LATEST RADAR TRENDS...EXPECT THAT ANY PCPN AND TS SHOULD
REMAIN SOUTH OF OF THE TERMINALS EARLY THIS EVENING...THROUGH IT
COULD CLIP THE SOUTHERN PORTIONS OF THE C90 TRACON AREA. AS THE
CENTER OF THE HIGH CONTINUES TO SHIFT TO THE EAST...WINDS HAVE
BECOME SSWLY AND ARE INCREASING TO ARND 10KT. LATEST RADAR IMAGERY
AND COASTAL OBSERVATIONS SHOW A LAKE BREEZE MOVING ONSHORE NEAR
KUGN...BUT THERE IS LITTLE WESTWARD PROGRESSION AND DO NOT EXPECT
THAT THE BOUNDARY WILL REACH AS FAR WEST AS ORD/MDW.
RATHER...EXPECT THAT WINDS WILL GRADUALLY BACK TO MORE SELY
THROUGH THE AFTERNOON AND INTO THE EVENING IN RESPONSE TO THE
LARGER SCALE PRESSURE PATTERN WITH THE HIGH MOVING OFF TO THE EAST
AND LOW PRESSURE DEVELOPING OVER THE CNTRL PLAINS.
THE OTHER CONCERN FOR THE PERIOD WILL BE TIMING THE NEXT ROUND OF
THUNDERSTORMS TO IMPACT THE REGION. WHILE THE ONGOING PCPN SHOULD
REMAIN SOUTH OF THE TERMINALS...CONFIDENCE IS HIGHER THAT ANOTHER
ROUND OF THUNDERSTORMS WILL DEVELOP TONIGHT OVER THE CNTRL
PLAINS/IOWA AND THEN TRACK EASTWARD. LATEST GUIDANCE IS A LITTLE
FASTER THAN PREVIOUS MODEL RUNS AND SUGGESTS THAT TS COULD REACH
RFD BY ARND 03Z...AND THEN QUICKLY PUSHING TO THE EAST ACROSS THE
CHICAGO AREA TERMINALS. WHILE CONFIDENCE IS RELATIVELY HIGH IN TS
IMPACTING THE TERMINALS OVERNIGHT TONIGHT...TIMING AND DURATION IS
A LITTLE LOWER. ALSO...AS THE MAIN SFC LOW TRACKS ALONG A
DEVELOPING WARM FRONT EXPECTED TO SET THROUGH CNTRL OR NRN IL/IN
AND WITH UPPER LEVEL FLOW SETTING UP TO BE PARALLEL TO THE SFC
FRONT...AN EXTENDED PERIOD OF TSRA IMPACTING THE TERMINALS IS
QUITE POSSIBLE OVERNIGHT AND POSSIBLY EVEN INTO TOMORROW MORNING.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM TO HIGH CONFIDENCE IN GENERAL WIND TRENDS.
* MEDIUM CONFIDENCE IN LAKE BREEZE DETAILS...AND THAT THE LAKE
BREEZE BOUNDARY WILL REMAIN EAST OF THE TERMINALS.
* MEDIUM TO HIGH CONFIDENCE IN TS IMPACTING THE TERMINALS THIS
EVENING AND TONIGHT...LOWER CONFIDENCE IN EXACT TIMING AND
DURATION.
* MEDIUM CONFIDENCE IN A PERIOD OF MVFR-IFR CIGS/VIS WITH THE
TSRA/PCPN OVERNIGHT TONIGHT AND INTO TOMORROW MORNING.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR. WX NIL. NELY WINDS.
FRIDAY...VFR. WX NIL. NELY WINDS.
SATURDAY...VFR. WX NIL. NELY WINDS BACKING NWLY LATE.
SUNDAY...CHANCE TSRA. MVFR POSSIBLE. NWLY WINDS BACKING SWLY.
MONDAY...CHANCE TSRA. MVFR POSSIBLE. SWLY WINDS VEERING NWLY
TUESDAY...SLIGHT CHANCE TSRA. VRBL WINDS.
KREIN
&&
.MARINE...
410 AM CDT
HIGH PRESSURE IS OVER THE REGION WITH LIGHT SOUTHWEST WINDS. WINDS
REMAIN LIGHT AND BECOME EAST THURSDAY MORNING AS A LOW PRESSURE
SYSTEM MOVES OVER THE SOUTHERN END OF THE LAKE. GUIDANCE DIFFERS ON
HOW STRONG THE LOW WILL BE SO WIND SPEEDS COULD BE STRONGER OVER THE
SOUTHERN END OF THE LAKE IF THE LOW IS STRONGER. THE LOW SHIFTS
EAST AND ANOTHER LOW PASSES WELL SOUTH OF THE LAKE OVER THE OHIO
RIVER LATE THIS WEEK. PERSISTENT NORTH TO NORTHEAST WINDS AT 20KT OR
LESS ARE EXPECTED THROUGH SATURDAY NIGHT. HIGH PRESSURE SPREADS
SOUTH OF THE LAKE WHILE A LOW SPREADS OVER THE LAKE SUNDAY NIGHT
WITH WINDS BCMG SOUTH SUNDAY EVENING AND REMAINING SOUTH TO
SOUTHWEST THROUGH MONDAY NIGHT.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039...7 PM WEDNESDAY TO 1 PM
THURSDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019...7 PM
WEDNESDAY TO 1 PM THURSDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1218 PM CDT WED JUN 24 2015
.UPDATE...
1217 PM CDT
ALL INDICATIONS THIS MORNING CONTINUE TO POINT TO A CLASSIC TYPE
HEAVY RAIN EVENT ACROSS THE AREA. THE THREAT OF SEVERE THUNDERSTORMS
IS ALSO DECENT WITH THIS ACTIVITY AS WELL LATER THIS EVENING...AND
THIS PRIMARILY LOOKS TO BE IN THE FORM OF STRONG STRAIGHT LINE WINDS.
SHOWERS...WITH SOME EMBEDDED THUNDERSTORMS CONTINUE TO WEAKEN OVER
CENTRAL ILLINOIS AS THEY MOVE AWAY FROM THE BETTER FOCUS OF LAST
NIGHTS LOW LEVEL JET. SATELLITE IMAGERY CONTINUES TO INDICATE CLOUD
TOPS WARMING WITH THIS ACTIVITY...AND EVEN INDICATES SOME BREAKS IN
THE CLOUDS OVER FAR NORTHERN ILLINOIS. FARTHER WEST...HOWEVER...AN
AREA OF CONVECTION OVER EASTERN NE AND NEAR FAR WESTERN IOWA
CONTINUES TO MAINTAIN ITSELF. IT IS CERTAINLY POSSIBLE THAT THIS
ACTIVITY COULD CONTINUE TO MOVE EAST OVER IOWA INTO THIS
AFTERNOON...THEN SHIFT MORE SOUTHEAST ALONG THE MLCAPE GRADIENT. THIS
ACTIVITY...SHOULD IT MAINTAIN ITSELF THOUGH THE DAY...WOULD LIKELY
MISS MOST OF MY AREA...POSSIBLY ONLY IMPACTING MY SOUTHWESTERN
COUNTIES. SOME OF THE LATEST HRRR SOLUTIONS ARE IN LINE WITH THIS
THINKING.
OTHERWISE...THE FOCUS CONTINUES TO CENTER ON THIS EVENING THROUGH
THE OVERNIGHT FOR THE POTENTIAL OF VERY HEAVY RAIN AND FLASH
FLOODING. IT IS STILL ANTICIPATED THAT RENEWED CONVECTION WILL
DEVELOP LATER THIS AFTERNOON/EARLY THIS EVENING OVER PORTIONS OF
EASTERN IOWA INTO NORTHWESTERN ILLINOIS ALONG AND ON THE COOL SIDE
OF A NORTHWARD MOVING WARM FRONTAL BOUNDARY. THIS ACTIVITY WOULD
THEN LIKELY CONTINUE TO GROW UPSCALE AS RENEWED DEVELOPMENT
CONTINUES UPSTREAM THANKS TO A PERSISTENT SOUTHWESTERLY 40+ KT LOW
LEVEL JET CONTINUALLY REPLENISHING THE DEEP MOISTURE. THESE STORMS
WILL OCCUR WITHIN AROUND A 2 INCH PRECIPITABLE WATER
ENVIRONMENT...SO EXTREMELY HEAVY RAIN RATES WILL BE A HIGH CONCERN.
ALSO...WITH CONTINUAL UPSTREAM DEVELOPMENT LOOKING LIKELY...TRAINING
AND BACKBULDING OF CELLS COULD RESULT IN PROLONGED PERIODS OF THESE
VERY HEAVY RAIN RATES OCCURRING OVER THE SAME AREAS. AS SUCH...SOME
ISOLATED AREAS OVER THE AREA COULD EXPERIENCE 4-5+ INCH AMOUNTS OF
RAIN BEFORE THIS ACTIVITY ABATES LATER TONIGHT OR EARLY THURSDAY
MORNING. THERE ARE STILL SOME UNCERTAINTIES ON WHERE EXACTLY THE
HEAVIEST RAINFALL AMOUNTS WILL FALL. HOWEVER...WITH THE ACTIVITY
LIKELY TO MOVE EAST-SOUTHEAST WITH TIME...IT WOULD APPEAR THAT AREAS
ALONG AND SOUTH OF INTERSTATE 88 WOULD LIKELY STAND THE BEST
POTENTIAL TO EXPERIENCE RAINFALL AMOUNTS IN EXCESS OF 1 TO 2 INCHES.
WITHIN THESE TRAINING THUNDERSTORMS...THE KINEMATIC FIELDS OVER THE
AREA WILL ALSO LIKELY SUPPORT FORWARD PROPAGATING EAST-SOUTHEASTWARD
MOVING BOWING SEGMENTS OVER THE AREA. THEREFORE...STRONG DAMAGING
WINDS...PERHAPS IN EXCESS OF 70 MPH...WILL ALSO BE A THREAT WITH
THESE STORMS. A TORNADO OR TWO CAN ALSO NOT BE RULED OUT. HOWEVER...
THIS THREAT APPEARS TO BE THE HIGHEST OVER MY SOUTHEASTERN CWA THIS
EVENING IN CLOSER PROXIMATELY TO THE APPROACHING WARM FRONTAL
BOUNDARY.
KJB
&&
.SHORT TERM...
320 AM CDT
THROUGH WEDNESDAY NIGHT...
STRONG TO SEVERE THUNDERSTORMS COMPRISE THE PRIMARY FORECAST
CONCERNS FOR TODAY AND TONIGHT.
EARLY THIS MORNING...SURFACE HIGH PRESSURE IS CENTERED ACROSS
CENTRAL ILLINOIS PROVIDING MOSTLY CLEAR SKIES AND LIGHT WINDS
ACROSS NORTHERN ILLINOIS AND NORTHWEST INDIANA. FARTHER WEST...A
SURFACE TROUGH IS ANALYZED FROM NORTHERN KANSAS NE ACROSS THE MID-
MISSOURI VALLEY INTO CENTRAL IOWA. WATER VAPOR IMAGERY SHOWS A
SUBTLE/SHEARED WAVE EMBEDDED WITHIN THE MAINLY ZONAL FLOW ALOFT
MOVING ACROSS NORTHERN IOWA WHERE NOCTURNAL THUNDERSTORMS HAVE
DEVELOPED MAINLY FOCUSED ACROSS THE I-80 CORRIDOR IN IOWA. NAM/GFS
INITIALIZE ON THIS AREA OF THUNDERSTORMS AND KEEPS THE FORCING
FOCUSED TO THE WEST OF THE FORECAST AREA THROUGH MOST OF THE DAY
TODAY...ALONG WITH THE INSTABILITY. CANT RULE OUT SOME DECAYING
ELEVATED CONVECTION PROPAGATING INTO THE FORECAST AREA LATER
TODAY...HOWEVER EXPECT MOST OF THE CWA TO BE DRY THIS MORNING INTO
AT LEAST EARLY EVENING. WILL HAVE TO KEEP AN EYE ON HOW EARLY
MORNING CONVECTION IMPACTS THE MOVEMENT OF THE WARM FRONT THROUGH
THE DAY.
THIS EVENING...SURFACE TROUGH/WARM FRONT IS PROGGED TO SETTLE
ACROSS CENTRAL/NORTHERN IOWA INTO NORTHERN ILLINOIS THOUGH THERE
ARE NOTABLE DIFFERENCES AT THIS POINT AS TO EXACTLY HOW FAR NORTH.
VERY STRONG INSTABILITY IS EXPECTED TO DEVELOP SOUTH OF THE FRONT
WITH THUNDERSTORMS EXPECTED TO REDEVELOP/RESTRENGTHEN ACROSS IOWA
AFTERNOON INTO THE EVENING AS ANOTHER SHEARED VORT LOBE TRAVERSES
ACROSS THE REGION AND RIGHT ENTRANCE REGION TO THE LOW LEVEL JET
PROVIDES ADDITIONAL SYNOPTIC SCALE ASCENT. ASSUMING ATMOSPHERE
EFFECTIVELY RECOVERS FROM MORNING CONVECTION...FAVORABLE
SHEAR/INSTABILITY PROFILES...IMPRESSIVE CYCLONICALLY CURVED
HODOGRAPHS AND WHAT SHOULD BE SUFFICIENT FORCING TO OVERCOME ANY
CAPPING INVERSION WILL RESULT IN STRONG TO SEVERE THUNDERSTORMS
DEVELOPING WEST OF THE CWA...POSSIBLY IN A DISCRETE/SUPERCELL MODE
INITIALLY WITH THE FULL GAMUT OF SEVERE WEATHER POSSIBLE.
STRENGTHENING NOCTURNAL LOW LEVEL JET INTO THE EVENING WILL RESULT
IN STORMS MERGING INTO AN MCS AND PUSHING EAST INTO THE LOCAL
FORECAST AREA. AS THIS OCCURS...EXPECT THE PRIMARY SEVERE THREAT
TO CHANGE TO MORE OF A STRAIGHT LINE WIND DAMAGE AND FLOODING
THREAT. CORFIDI VECTORS DROP OFF TO AROUND 5 KT OR SO ON THE
SOUTHERN FLANK OF THE STORMS SO BACKBUILDING AND TRAINING
THUNDERSTORMS REMAIN A CONCERN. A FLASH FLOOD WATCH WAS ISSUED
YESTERDAY AND OPTED TO EXPAND NORTHWARD GIVEN THE TRENDS FROM THE
GFS/NAM...ALTHOUGH CONFIDENCE IS ADMITTEDLY A BIT LOWER ACROSS THE
NORTHERN TIER OF COUNTIES.
DEUBELBEISS
&&
.LONG TERM...
340 AM CDT
THURSDAY THROUGH TUESDAY...
THE UPPER LEVEL ZONAL FLOW FINALLY SHIFTS EAST LATE THIS WEEK AS AN
UPPER LEVEL TROUGH MOVES OVER THE REGION FRIDAY NIGHT. THE TROUGH
AXIS SHIFTS EAST SATURDAY WITH NORTHWEST FLOW SUNDAY. ANOTHER WEAKER
TROUGH IS POSSIBLE EARLY NEXT WEEK.
A SFC LOW WILL BE OVER NORTHERN IL AND NORTHWEST IN THURSDAY MORNING
AS A DYING MCS SLOWLY SHIFTS EAST. RAISED QPF AMOUNTS THURSDAY
MORNING AS THE DYING MCS SHOULD PRODUCE AT LEAST ANOTHER 0.35-0.5
INCHES OF RAIN SOUTH OF I-88. GUIDANCE DIFFERS ON HOW QUICKLY THE
MCS WILL EXIT THE REGION...BUT HAVE HIGH CONFIDENCE IN DRY
CONDITIONS THURSDAY NIGHT.
SADLY THERE IS A VERY SMALL BREAK BEFORE THE NEXT LOW PRESSURE
BRINGS MORE RAIN AND STORMS TO AREAS SOUTH OF I-80 FRIDAY. THE NEXT
LOW FORMS OVER THE SOUTHERN PLAINS THURSDAY NIGHT. IT THEN PASSES
OVER THE MID MISSISSIPPI VALLEY AND ALONG THE OHIO RIVER THROUGH
SATURDAY NIGHT. IT LOOKS LIKE THE MAJORITY OF PRECIP WILL FALL OVER
CENTRAL AND SOUTHERN IL...BUT KEPT A SLIGHT CHANCE TO CHANCE OF
THUNDERSTORMS SOUTH OF I-88. WE FINALLY SEE A DRY SPELL LATE THIS
WEEK AS THE LOW SHIFTS EAST AND HIGH PRESSURE SPREADS OVERHEAD.
THE NEXT CHANCE OF RAIN AND STORMS ARRIVES EARLY NEXT WEEK AS AN
UPPER LEVEL TROUGH SWINGS THROUGH. GUIDANCE DIFFERS ON HOW STRONG
THE TROUGH WILL BE AND HOW FAR SOUTH IT WILL TRAVEL...BUT HAVE
ENOUGH CONFIDENCE TO KEEP A CHANCE OF PRECIP IN THE FORECAST. WE
COULD SEE MULTIPLE VORTICITY STREAMERS SWING THROUGH AS THE TROUGH
SITS OVERHEAD SO KEPT A CHANCE OF PRECIP FROM SUNDAY NIGHT THROUGH
TUESDAY. DESPITE THE CONSTANT CHANCE OF RAIN...ONLY EXPECTING
PERIODS OF SHOWERS AND STORMS AT THIS POINT AND NOT COMPLETE
RAIN OUTS.
FOR TEMPS...THURSDAY LOOKS LIKE THE WARMEST DAY WITH HIGHS IN THE
UPPER 70S TO LOW 80S. LAKE COOLING WILL KEEP LAKEFRONT LOCATIONS IN
THE LOW 70S. COOLER AIR SINKS SOUTH THURSDAY NIGHT LEADING TO HIGH
TEMPS FRIDAY IN THE 70S WITH 60S ALONG THE LAKE. A SLOW WARM UP IS
EXPECTED WITH HIGHS BACK IN THE LOW 80S TUESDAY.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* CHANCE OF LAKE BREEZE DEVELOPMENT LATE THIS AFTERNOON.
* THUNDERSTORMS LIKELY OVERNIGHT TONIGHT.
KREIN
//DISCUSSION...UPDATED 12Z...
AT THE SURFACE...A LARGE AREA OF HIGH PRESSURE IS CENTERED OVER
THE SOUTHERN TIP OF LAKE MICHIGAN KEEPING A VERY WEAK PRESSURE
GRADIENT OVER THE REGION. A MID LEVEL IMPULSE CROSSING THE MIDDLE
MISSISSIPPI VALLEY IS BRINGING AN AREA OF SHOWERS AND
THUNDERSTORMS TO SERN IOWA AND INTO CENTRAL ILLINOIS. BASED ON THE
LATEST RADAR TRENDS...EXPECT THAT ANY PCPN AND TS SHOULD REMAIN
SOUTH OF OF THE TERMINALS THIS MORNING...THROUGH IT COULD CLIP THE
SOUTHERN PORTIONS OF THE C90 TRACON AREA. AS THE CENTER OF THE
HIGH SHIFT TO THE EAST TODAY...WINDS SHOULD BACK FROM SSWLY TO
SELY THROUGH THE DAY. BY THIS AFTERNOON...WINDS ALOFT SHOULD BE
LESS THAN 10KT WHILE SFC WINDS ALSO REMAIN LESS THAN 10KT...SO
THERE IS A CHANCE FOR A LAKE BREEZE TO FORM. CONFIDENCE IS LOWER
ON WHETHER THE LAKE BREEZE WILL PUSH FAR ENOUGH INLAND TO REACH
ORD/MDW...AND WHETHER WINDS WILL BACK FURTHER FROM SELY TO ELY. AT
THIS POINT...CONFIDENCE IS LOW ON THE LAKE BREEZE REACHING ORD/MDW
WITH WINDS SYNOPTICALLY SETTING UP SELY THIS AFTERNOON.
THE OTHER CONCERN FOR THE PERIOD WILL BE TIMING THE NEXT ROUND OF
THUNDERSTORMS TO IMPACT THE REGION. WHILE THE ONGOING PCPN SHOULD
REMAIN SOUTH OF THE TERMINALS...CONFIDENCE IS HIGHER THAT ANOTHER
ROUND OF THUNDERSTORMS WILL DEVELOP TONIGHT OVER THE CNTRL
PLAINS/IOWA AND THEN TRACK EASTWARD AS A STRONG LINE OF
THUNDERSTORMS. LATEST GUIDANCE SUGGESTS THAT TS COULD REACH RFD
ARND 06Z...AND THEN QUICKLY PUSHING TO THE EAST ACROSS THE CHICAGO
AREA TERMINALS. WHILE CONFIDENCE IS RELATIVELY HIGH IN TS
IMPACTING THE TERMINALS OVERNIGHT TONIGHT...TIMING AND DURATION IS
A LITTLE LOWER AND THERE IS A CHANCE THAT TS COULD REACH THE
TERMINALS A LITTLE EARLIER THAN CURRENTLY INDICATED IN THE TAFS.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM TO HIGH CONFIDENCE IN GENERAL WIND TRENDS.
* LOW TO MEDIUM CONFIDENCE IN LAKE BREEZE DETAILS AND WHETHER THE
LAKE BREEZE WILL REACH ORD/MDW.
* MEDIUM TO HIGH CONFIDENCE IN TS IMPACTING THE TERMINALS THIS
EVENING AND TONIGHT...LOWER CONFIDENCE IN EXACT TIMING...
DURATION AND IMPACTS.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR. WX NIL. NELY WINDS.
FRIDAY...VFR. WX NIL. NELY WINDS.
SATURDAY...VFR. WX NIL. NELY WINDS BACKING NWLY LATE.
SUNDAY...CHANCE TSRA. MVFR POSSIBLE. NWLY WINDS BACKING SWLY.
MONDAY...CHANCE TSRA. MVFR POSSIBLE. SWLY WINDS VEERING NWLY
TUESDAY...SLIGHT CHANCE TSRA. VRBL WINDS.
KREIN
&&
.MARINE...
410 AM CDT
HIGH PRESSURE IS OVER THE REGION WITH LIGHT SOUTHWEST WINDS. WINDS
REMAIN LIGHT AND BECOME EAST THURSDAY MORNING AS A LOW PRESSURE
SYSTEM MOVES OVER THE SOUTHERN END OF THE LAKE. GUIDANCE DIFFERS ON
HOW STRONG THE LOW WILL BE SO WIND SPEEDS COULD BE STRONGER OVER THE
SOUTHERN END OF THE LAKE IF THE LOW IS STRONGER. THE LOW SHIFTS
EAST AND ANOTHER LOW PASSES WELL SOUTH OF THE LAKE OVER THE OHIO
RIVER LATE THIS WEEK. PERSISTENT NORTH TO NORTHEAST WINDS AT 20KT OR
LESS ARE EXPECTED THROUGH SATURDAY NIGHT. HIGH PRESSURE SPREADS
SOUTH OF THE LAKE WHILE A LOW SPREADS OVER THE LAKE SUNDAY NIGHT
WITH WINDS BCMG SOUTH SUNDAY EVENING AND REMAINING SOUTH TO
SOUTHWEST THROUGH MONDAY NIGHT.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039...7 PM WEDNESDAY TO 1 PM
THURSDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019...7 PM
WEDNESDAY TO 1 PM THURSDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
406 PM EDT WED JUN 24 2015
.SYNOPSIS...
ISSUED AT 400 PM EDT WED JUN 24 2015
A WARM FRONT WILL MOVE NORTH INTO THE REGION TONIGHT INTO
THURSDAY...PROVIDING THE FOCUS FOR SHOWERS AND THUNDERSTORMS.
LOCALLY HEAVY RAINFALL WILL BE THE MAIN THREAT...BUT A RISK OF
DAMAGING WINDS DOES EXIST WITH THE STRONGEST STORMS. LOWS TONIGHT
WILL BE IN THE LOWER TO MIDDLE 60S. CLOUDS AND EXPECTED RAINFALL
WILL KEEP HIGHS IN THE MIDDLE 70S TO NEAR 80.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 400 PM EDT WED JUN 24 2015
AS USUAL WITH SUMMER CONVECTION...A VERY COMPLICATED SETUP WITH
OVERNIGHT AND THURSDAY CONVECTION HIGHLY DEPENDENT ON WHAT HAPPENS
UPSTREAM TONIGHT. SEVERE WEATHER AND LOCALLY HEAVY RAINFALL THE MAIN
CONCERNS.
SEVERAL CLUSTERS OF CONVECTION ONGOING THIS AFTERNOON. WEAKENING
CONVECTION IN IL HAS STALLED NORTHWARD MOVEMENT OF WARM FRONTAL
BOUNDARY BUT CONVECTION OVER IA BEING FUELED BY STRONG MOISTURE
ADVECTION AND LOW LEVEL JET OVER SURGING BOUNDARY. EXPECT EARLY
EVENING TO BE DRY IN OUR REGION BUT FIRST FOCUS WILL BE ON DECAYING
COMPLEX FROM IA MOVING INTO OUR NORTHWEST LATER THIS EVENING. HRRR
AND RAP NOW PICKING UP ON THIS WHILE LOWER RES SPECTRAL MODELS SEEM
TO KEEP THIS SYSTEM TOGETHER AND MOVE ACROSS OUR NORTH. THINK THE
HIGHER RES GUIDANCE HAVE A GOOD HANDLE ON THIS SYSTEM AS INSTABILITY
REMAINS WEAK TO NON EXISTENT UNTIL LATER TONIGHT WHEN MUCAPES RISE
TO BETWEEN 1000 AND 1500 J/KG. 0-3 KM AND DEEPER LAYER SHEAR ALSO
INCREASE LATE WITH STRENGTHENING WEST TO SOUTHWEST LOW LEVEL JET
FUELING SECONDARY MCS DEVELOPMENT UPSTREAM. THIS SYSTEM EXPECTED TO
PROPAGATE INTO OUR WEST AND SOUTH CLOSER TO DAYBREAK. THIS WOULD BE
THE SYSTEM TO BRING FIRST ROUND OF POTENTIAL SEVERE WEATHER IN FORM
OF MAINLY DAMAGING WINDS AND HEAVY RAINFALL BUT AN ISOLATED TORNADO
COULD OCCUR GIVEN MAGNITUDE OF SHEAR AND LOW LEVEL BOUNDARY WITH
BACKED WINDS. THUS THE ENHANCED TO SLIGHT RISK OUTLOOK FOR THIS
AREA.
NEXT FOCUS WILL BE ON POSSIBILITY OF ANOTHER ROUND OF SEVERE WEATHER
AND HEAVY RAIN THURSDAY AFTERNOON ALONG SFC BOUNDARY. THIS REMAINS
HIGHLY CONDITIONAL ON WHAT HAPPENS OVERNIGHT AND HOW MUCH WE CAN
DESTABILIZE THURSDAY AFTERNOON. SOUTHERN AREAS LOOK TO BE IN THE
MOST FAVORABLE AREA AND HEAVY RAINFALL REMAINS POSSIBLE WITH PWAT
VALUES IN THE 1.25 TO 1.50 INCH RANGE. ALL OF THESE FACTORS FOR
HEAVY RAINFALL POTENTIAL WITH MULTIPLE SYSTEMS COUPLED WITH THE VERY
SATURATED GROUND AND STILL NEARLY FULL RIVERS...STREAMS AND
RESERVOIRS WARRANTED THE FLASH FLOOD WATCH IN THESE AREAS THAT
CANNOT TAKE MUCH RAINFALL.
&&
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 400 PM EDT WED JUN 24 2015
THURSDAY NIGHT THROUGH WEDNESDAY...
WESTERLY FLOW WILL BUCKLE AND THE EASTERN TROF WILL DEEPENG
BEGINNING FRIDAY AND PERSISTING THROUGH THE REMAINDER OF THE
EXTNENDED FORECAST. WITH THE HIGH AMPLITUDE RIDGE OVER THE WESTERN
US...EXPECT TO SEE CONTINUED BELOW NORMAL TEMPERATURES...MOSTLY
CLOUDY SKIES AND CONTINUED THREAT OF SHOWERS / THUNHDERSTORMS.
BAROCLINIC DEEPENING FORECAST TO OCCUR OVER THE CENTRAL MISSISSIPPI
RIVER VALLEY FRIDAY NIGHT EJECTS INTO THE OHIO RIVER VALLEY DURING
THE DAY SATURDAY AND THIS WILL FAVOR RAINFALL OVER THE EASTERN HALF
OF THE CWA. THIS WILL BE SLOW TO MOVE OUT AS YET ANOTHER IN A SERIES
OF SHORT WAVES DIVES INTO THE REGION. THIS WILL DEEPEN THE TROF.
ALL LONG RANGE MODELS SUGGEST SEVERAL SHORTWAVES TO DROP THROUGH THE
GREAT LAKES REGION THROUGHOUT THE PERIOD...AND EACH HAS SLIGHT
TIMING AND INTENSITY DIFFERENCES. WITH THE WARM WATER TEMPERATURES
AND THE COLD FLOW OVER THE REGION...EXPECT A PROLONGED PERIOD OF
CLOUDS AND -SHRA TO CONTINUE FROM SUN-WEDNESDAY. APPEARS THAT THE
FRONTAL BOUNDARY WILL REMAIN SOUTH...OVER THE OHIO RIVER VALLEY AND
THIS WILL HELP KEEP SIGNIFICANT AND HEAVIER RAINFALL TO OUR SOUTH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 133 PM EDT WED JUN 24 2015
THUNDERSTORM CHANCES REMAIN PRIMARY CONCERN FOR AVIATION THIS
PERIOD. MID AND HIGH CLOUDS TO THIN THIS AFTERNOON BUT SHOULD SEE
VFR CONDITIONS THROUGH THE EVENING. A CONVECTIVE COMPLEX IS
EXPECTED TO MOVE THROUGH IL LATE TONIGHT AND LIKELY WILL DIVE INTO
NORTHERN INDIANA AFTER 06Z. SPREAD AMONG HIRES MODELS REMAINS HIGH
ON TRACK AND LOCATION OF STRONGEST THUNDERSTORMS. LOOKS LIKE BOTH
TAF SITES SHOULD AT LEAST SEE SOME SHOWERS WITH VICINITY THUNDER
SO CONTINUED THAT TREND WITH THIS PACKAGE UNTIL MORE DETAIL CAN BE
ADDED. IFR CIGS AND VIS POSSIBLE IF THIS SYSTEM TRACKS DIRECTLY
OVER TAF SITES WITH STRONG WIND GUSTS AND HEAVY RAIN POTENTIAL AS
WELL...MAINLY AFTER 06Z.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...FLASH FLOOD WATCH FROM LATE TONIGHT THROUGH THURSDAY EVENING FOR
INZ003-012>015-020-022>027-032>034.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...FISHER
SHORT TERM...LASHLEY
LONG TERM...LEWIS
AVIATION...LASHLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS DES MOINES IA
650 PM CDT THU JUN 25 2015
.SHORT TERM /TONIGHT/...
ISSUED AT 356 PM CDT THU JUN 25 2015
MAIN FORECAST CONCERN WAS FOCUSED ON WEAK SHORTWAVE
CUTTING ACROSS NEBRASKA AND POTENTIALLY BRINGING SOME LOCALLY HEAVY
RAIN TO FAR SOUTHERN IOWA TONIGHT. BOUNDARY LOOKS TO BE SET UP IN
NORTHERN MISSOURI AND POSSIBLY SHIFT NORTH ENOUGH TO THE IOWA BORDER
TONIGHT...BUT HAVE FAIRLY HIGH CONFIDENCE THAT IS THE FARTHEST
EXTENT NORTH IT WILL REACH. DECENT MOISTURE CONVERGENCE ALONG THE
MO/IA BORDER WITH STILL A GOOD ATMOSPHERE FOR EFFICIENT RAIN
PRODUCERS. PRECIPITABLE WATER VALUES AROUND 1.5 INCHES AND WARM
LAYER CLOUD DEPTHS IN THE 3500-3800 METER RANGE. FORWARD PROPAGATION
CORFIDI VECTORS ORIENTED WEST TO EAST PROVIDING SOME TRAINING
POTENTIAL ALONG THE FAR SOUTH. THE 25.19Z HRRR KEEPS MUCH OF THE
HEAVY CONVECTION IN MISSOURI. HOWEVER...INCREASED POPS AND QPF OVER
THE SOUTHERN TIER OF COUNTIES ALONG THE MISSOURI BORDER. OTHER
CONCERN WAS ANOTHER WEAK SHORTWAVE TO PROVIDE SOME ELEVATED SHOWERS
AND ISOLATED THUNDERSTORM OVER THE REMAINDER OF THE FORECAST AREA.
QPF AMOUNTS SHOULD REMAIN UNDER QUARTER OF AN INCH AND THUS LOW
IMPACT ON ANY ONGOING FLOODING
.LONG TERM /FRIDAY THROUGH THURSDAY/...
ISSUED AT 356 PM CDT THU JUN 25 2015
A MUCH...MUCH QUIETER 7 DAYS AHEAD IN THIS LONG TERM FCST PERIOD.
WATER VAPOR IMAGERY PICKING UP ON HIGH PRESSURE COMING ONSHORE NEAR
THE OREGON COASTLINE. THIS HIGH PRESSURE WILL HAVE SIGNIFICANT
INFLUENCE ON OUR WEATHER MUCH OF NEXT WEEK.
FRIDAY MORNING...MODELS PICKING UP ON A SHORTWAVE CONTINUING THROUGH
SOUTHERN IA/NORTHERN MO. ISENTROPIC LIFT PERSISTING INTO 12Z AS THIS
SYSTEM WILL LIKELY BE CLIPPING AT LEAST THE SOUTHERN TWO TO THREE
TIERS OF COUNTIES IN IA. WITH YESTERDAY/S BOUNDARY LINGERING IN
NORTHERN MO...A LOT OF THE MOISTURE FROM THURSDAY/S SYSTEM STILL
AROUND. MODELS FOCUSING IN ON PWATS BTX 1.5 AND 1.75 INCHES...WHICH
IS AROUND +1 TO +2 STD DEV. GOOD SUPPORT ALOFT AS MID-LEVEL Q-VECTOR
CONV PRESENT TO INCREASE LIFT. 0-6KM MIXING RATIOS AROUND 7 G/KG
WHICH IS DECENT ENOUGH. OVERALL SOUNDING PROFILE MUCH LESS SATURATED
THAN MOST OF THIS WEEK...SO THIS SYSTEM WILL NOT BE THE MOST
EFFICIENT IN RAIN PRODUCTION.
FRI AFTERNOON TEMPS...850MB TEMPS AROUND 12C IN OUR EAST AND 14C IN
OUR WEST...ABOUT -1 TO -2 STD DEV. THURSDAY/S 850 MB TEMPS WERE
AROUND 14C NE TO 17C SW. AM EXPECTING SUNSHINE TO BREAK
THROUGH...BUT NOT A LOT...SO HAVE KEPT TEMPS IN THE MID 70S.
FRI AFTERNOON THUNDERSTORM POTENTIAL...0-6KM MUCAPE VALUES BTX 700
AND 1000 J/KG WHICH WHICH IS MINIMAL. 0-6KM BULK SHEAR NEAR
30KTS...ALSO MINIMAL. LCL HEIGHTS ABOVE 1000M. OVERALL SOUNDING
PROFILE SUGGESTS ANYTHING THAT FORMS WOULD BE ELEVATED. THUS
OVERALL...AM EXPECTING NIL SVR/TOR THREAT FRI PM AND THERE MAY BE A
FEW SHORT LIVED NON-SEVERE STORMS PRIMARILY IN OUR NW.
FOR SATURDAY NIGHT INTO SUNDAY EVENING...MODELS CONSISTENT WITH
PROPAGATING AN AREA OF LOW PRESSURE FROM NW MINNESOTA INTO SE
MINNESOTA. A WEAK COLD FRONT WILL BE ATTACHED TO THIS AND PUSHING
THROUGH IA DURING THE DAYTIME. THE 12Z GFS IS A FAST OUTLIER WITH
THIS SYSTEM AS IT PLACES THE BOUNDARY EAST OF OUR CWA BY 12-15Z SUN.
HAVE MAINLY DISREGARDED THE GFS AND WENT WITH AN AVERAGE OF OTHER
MODELS. PWATS JUMP FROM AROUND 1.25 TO 1.5 INCHES AND 0-6KM MUCAPE
VALUES ARE AROUND 400 TO 600 J/KG. POSITION OF FRONT DURING PEAK
DAYTIME HEATING IMPORTANT FOR SVR POTENTIAL. AS OF NOW...ALL SIGNS
POINT TO THIS BOUNDARY BEING WELL EAST OF THE CWA BY DAYTIME
HEATING.
FOR MONDAY AND THE REST OF THIS LONG TERM FCST PERIOD...PERSISTENCE
BECOMES A GOOD FORECAST THROUGH MID-WEEK. AN UPPER LEVEL TROUGH OVER
THE NORTHEASTERN US AND AN UPPER LEVEL RIDGE OVER THE MOUNTAIN WEST
WILL KEEP THE DMX CWA IN NORTHWESTERLY FLOW SEEMING INTO THE NEXT
THU/FRI/SAT TIMEFRAME. A HUGE THERMAL RIDGE WILL BUILD OVER THE
MOUNTAIN WEST COINCIDENT WITH THE UPPER LEVEL HIGH. THE RIDGE WILL
STAY TO OUR WEST AND 850 MB TEMPS WILL BE IN THE DMX CWA WILL BE
AROUND 15C TO OUR EAST AND 18C TO THE WEST. MODELS HINTING AT
THERMAL RIDGE CRASHING DOWN INTO IA SOMETIME LATER IN THE
WEEK...BRINGING A RETURN TO POP CHANCES TO THE AREA.
&&
.AVIATION...26/00Z
ISSUED AT 650 PM CDT THU JUN 25 2015
THERE WILL BE A BRIEF BREAK IN THE MVFR CIGS BUT AN UPPER LEVEL WAVE
WILL PUSH INTO IA LATE EVENING AND OVERNIGHT THROUGH FRIDAY MORNING
LOWERING CIGS ONCE AGAIN AND BRINGING SOME SCT SHRA/TSRA TO MOST TAF
LOCATIONS. SFC FLOW WILL REMAIN GENERALLY AOB 10KTS OUT OF A N TO
NE DIRECTION.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...KOTENBERG
AVIATION...FAB
AREA FORECAST DISCUSSION
NWS DES MOINES IA
342 PM CDT WED JUN 24 2015
.SHORT TERM /TONIGHT/...
ISSUED AT 341 PM CDT WED JUN 24 2015
COMPLEX SCENARIO SETTING UP ACROSS IOWA TONIGHT WITH A
WARM FRONT SURGING NORTH-NORTHEAST INTO SOUTHWEST IOWA PROVIDING
SOME DESTABILIZATION OVER SOUTHWEST IOWA. MUCH OF THIS AREA REMAINS
CAPPED AT THE MOMENT...BUT WITH IMPRESSIVE EFFECTIVE SHEAR AND HIGH
CAPE VALUES AVAILABLE...IF STORMS DEVELOP IN THIS LOCATION THEY
LIKELY WILL RAPIDLY BECOME SEVERE THIS AFTERNOON AND EVENING.
SUPERCELLS ARE CERTAINLY POSSIBLE ON INITIATION WITH STRONG VEERING
AND DEEP LAYER SHEAR WILL PROVIDE A TORNADIC THREAT THROUGH THE MID-
EVENING HOURS.
HOWEVER...THINKING THIS AREA SHOULD REMAIN CAPPED UNTIL LLJ DEVELOPS
TONIGHT COMBINED WITH THE TIMING OF A STRONG SHORTWAVE OVER THE HIGH
PLAINS PUSH ACROSS THE STATE. EXPECTING THE WARM FRONT TO SURGE
NORTH BETWEEN THE INTERSTATE 80 TO HIGHWAY 20 CORRIDOR. STORM
REDEVELOPMENT THIS EVENING LOOKS TO BETWEEN 02Z TO 05Z THURSDAY OVER
THIS CORRIDOR FROM WEST TO EAST AND THE FRONT SHOULD LIGHT UP ALONG
THIS REGION. THE 24.19Z HRRR HAS A DECENT HANDLE ON CURRENT RADAR
TRENDS...ALTHOUGH DIMINISHES THE CURRENT CONVECTION OVER
CRAWFORD/CARROLL COUNTIES THIS AFTERNOON. POTENTIAL FOR STORMS TO
LINGER A LITTLE LONGER THAN WHAT THE HRRR SUGGESTS BUT STILL LOOKING
AT A BREAK BETWEEN REDEVELOPMENT LATER THIS EVENING. SEVERE
POTENTIAL STILL EXISTS DURING THE OVERNIGHT BUT LOOKING MORE LIKELY
STRAIGHT LINE WIND EVENT POTENTIAL.
.LONG TERM /THURSDAY THROUGH WEDNESDAY/...
ISSUED AT 341 PM CDT WED JUN 24 2015
MAIN SHORT WAVE TO TRACK SOUTHEAST OF AREA BY 12Z...BUT RESIDUAL
CONVECTION MAY LINGER OVER THE SOUTHEAST THROUGH MORNING. AS FRONT
SAGS SOUTH THURSDAY...EXPECTING A BREAK FROM THE CONVECTION THROUGH
LATE AFTERNOON. ANOTHER UPPER LEVEL SHORTWAVE WILL DROP SOUTHEAST
ACROSS THE AREA THURSDAY NIGHT AND INTO FRIDAY WITH ENOUGH LIFT AND
INSTABILITY TO PRODUCE SCT THUNDERSTORMS THROUGH THE DAY. WITH
CLOUDS ACROSS THE REGION EXPECT THAT HIGHS WILL BE HELD BACK IN THE
70S FOR ALL OF THE AREA. THE TROUGH FINALLY PULLS SOUTHEAST OF THE
REGION FRIDAY NIGHT WITH A PERIOD OF QUIET WEATHER FROM FRIDAY NIGHT
THROUGH SATURDAY EVENING. OVER THE NEXT FEW DAYS THE PATTERN WILL
SHIFT TO A NORTHWESTERLY FLOW ALOFT. THIS WILL LESSEN THE CHANCES
FOR HEAVY RAINFALL AND ALSO BRING TEMPERATURES TO NEAR NORMAL OR
SLIGHTLY BELOW NORMAL. ANOTHER NORTHERN STREAM SHORTWAVE AND COOL
FRONT WILL DROP SOUTH SATURDAY EVENING WITH ADDITIONAL SCATTERED
THUNDERSTORMS SUNDAY. HIGHS SATURDAY AND SUNDAY WILL BE SOMEWHAT
COOLER WITH NORTHWEST FLOW. HIGHS WILL REMAIN IN THE UPPER 70S TO
LOWER 80S. WITH THE NORTHWEST FLOW IN PLACE THROUGH MIDWEEK NEXT
WEEK...EXPECT MORE OF THE SAME. THE RIDGE SHOULD REMAIN WEST OF IOWA
WITH SOME CHANCES FOR SHOWERS OR THUNDERSTORMS AS COOL FRONTS DROP
SOUTH INTO THE PLAINS AND GREAT LAKES. TEMPERATURES WILL CHANGE
LITTLE WITH HIGHS IN THE 70S TO LOWER 80S AND LOWS IN THE 50S TO
60S.
&&
.AVIATION...24/18Z
ISSUED AT 115 PM CDT WED JUN 24 2015
STORM ACTIVITY WILL CONTINUE ACROSS CENTRAL TO NORTH-CENTRAL IOWA
THIS AFTERNOON INTO THE EVENING. CERTAINLY MVFR FOR CIGS AND VIS
ARE POSSIBLE AND EVEN TO IFR/LIFR CONDITIONS WITH THE HEAVY
TS...BUT LOW CONFIDENCE WITH MENTIONING IFR/LIFR CONDITIONS AS
DIFFICULT TO TIME AND LOCATE OF STORMS LATER THIS AFTERNOON. ONCE
THIS FIRST ROUND OF STORMS MOVES EAST BY 22Z...ANOTHER ROUND LOOKS
TO DEVELOP ALONG THE WARM FRONT LATER THIS EVENING. HAVE MVFR VIS
OR CIGS FOR RAIN MENTIONED BY 03Z.
&&
.HYDROLOGY...
ISSUED AT 341 PM CDT WED JUN 24 2015
WILL STILL NEED TO CONSIDER FLASH FLOODING OVERNIGHT AND HAVE
EXPANDED THE WATCH FARTHER WEST. VERY GOOD MOISTURE TRANSPORT...
WARM LAYER CLOUD DEPTHS IN THE 13-14KFT RANGE AND PRECIPITABLE
WATER VALUES WELL OVER 2 INCHES TONIGHT. FAIRLY HIGH CONFIDENCE IN
WIDESPREAD FLASH FLOODING OVER THE INTERSTATE 80 TO HIGHWAY 20
CORRIDOR. RAINFALL RATES OF 2 TO 4 INCHES PER HOUR ARE LIKELY AND
WITH THE RAIN THAT FELL ALREADY TODAY...IT WILL NOT TAKE MUCH TO
CAUSE SOME FLASH FLOODING AND POTENTIAL SIGNIFICANT FLASH
FLOODING ISSUES OVER THE AFOREMENTIONED CORRIDOR. THUS...EXPANDED
THE FLASH FLOOD WATCH FURTHER WEST AND INCREASED POPS AND QPF
CONSIDERABLY B/T 03-09Z THURSDAY.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR ADAIR-APPANOOSE-
AUDUBON-BLACK HAWK-BOONE-BREMER-BUTLER-CALHOUN-CARROLL-CLARKE-
CRAWFORD-DALLAS-DAVIS-FRANKLIN-GREENE-GRUNDY-GUTHRIE-HAMILTON-
HARDIN-HUMBOLDT-JASPER-LUCAS-MADISON-MAHASKA-MARION-MARSHALL-
MONROE-POLK-POWESHIEK-SAC-STORY-TAMA-WAPELLO-WARREN-WEBSTER-
WRIGHT.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...REV
AVIATION...PODRAZIK
HYDROLOGY...PODRAZIK
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
322 PM CDT WED JUN 24 2015
.SYNOPSIS...
ISSUED AT 305 PM CDT WED JUN 24 2015
12Z UA ANALYSYS HAS AN 850MB WARM FRONT FROM CENTRAL
NEBRASKA...THROUGH SOUTHWEST IOWA...AND INTO SOUTHERN ILLINOIS.
ALONG AND SOUTH OF THIS FRONT WAS VERY WARM AND MOIST AIR. A WEAK
LLJ RAN FROM WEST TEXAS INTO CENTRAL KANSAS. SATELLITE/RADAR
TRENDS THROUGH MID AFTERNOON HAS A LOOSELY ORGANIZED CONVECTIVE
COMPLEX MOVING ACROSS IOWA WITH ANOTHER DEVELOPING BACK ALONG THE
MISSOURI RIVER.
18Z SFC DATA PLACES AN INFERRED LOW JUST EAST OF KOMA WITH A WARM
FRONT RUNNING FROM THE LOW TO NEAR KSTL. DEW POINTS ALONG AND
SOUTH OF THE WARM FRONT WERE IN THE UPPER 60S TO LOWER 70S. NORTH
OF THE WARM FRONT DEW POINTS WERE IN THE 50S TO LOWER 60S.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 305 PM CDT WED JUN 24 2015
RADAR AND RAP TRENDS WILL TAKE THE CURRENT CONVECTIVE COMPLEX EAST
LATE THIS AFTERNOON AND INTO THE EARLY EVENING. THE LACK OF
INSTABILITY ACROSS THE AREA MEANS THE COMPLEX WILL BE RAIN WITH
EMBEDDED THUNDERSTORMS. LOCALLY HEAVY RAINFALL WILL BE POSSIBLE
WITH THE STRONGER CONVECTION.
THERE ARE STILL QUESTIONS REGARDING THE OVERALL SEVERE THREAT FOR
LATE THIS AFTERNOON AND EVENING. THE SECONDARY CONVECTIVE COMPLEX
BACK ALONG THE MISSOURI RIVER IN WESTERN IOWA MAY POSE THE BETTER
THREAT OF SEVERE STORMS. IF SEVERE STORMS DO OCCUR LATE THIS
AFTERNOON AND EVENING...AREAS SOUTH OF I-80 WOULD BE MORE AT
THREAT.
AFTER SUNSET AND THROUGH SUNRISE THURSDAY...THE SECONDARY
CONVECTIVE COMPLEX WILL GROW UPSCALE AS FORCING AND MOISTURE
INCREASES ACROSS THE AREA. THE MODELS DO SUGGEST A SURFACE LOW
MOVING THROUGH THE CENTRAL PART OF THE AREA TONIGHT HELPING TO
ENHANCE THE RAINFALL. HEAVY RAIN IS DEFINITELY A THREAT AS STORMS
MAY MOVE REPEATEDLY OVER THE SAME AREAS.
BASED ON WHAT HAS ALREADY OCCURRED TODAY...RAINFALL OF 2 TO 4
INCHES IS PLAUSIBLE SHORTLY AFTER SUNRISE THURSDAY.
ON THURSDAY...RAIN WILL SLOWLY END FROM NORTHWEST TO SOUTHEAST
DURING THE DAY. IF CLOUDS REMAIN ACROSS THE AREA FOR MUCH OF THE
DAY...THE NORTH HALF OF THE AREA MAY BE DRY DURING THE AFTERNOON
HOURS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 305 PM CDT WED JUN 24 2015
FORECAST HIGHLIGHTS OF THE LONG TERM PERIOD INCLUDE A TRANSITION TO
NORTHWEST FLOW...COOLER TEMPERATURES...AND PERIODIC RAIN CHANCES.
FOR THURSDAY NIGHT...THE FAR SOUTHERN FRINGE REMAINS IN THE MARGINAL
RISK AREA FOR SEVERE STORMS ALONG THE RESIDUAL BOUNDARY. WILL ALSO
HAVE TO MONITOR THIS AREA FOR HEAVY RAIN PER THE 12Z NAM...ALTHOUGH
THAT PARTICULAR MODEL IS THE MOST BULLISH ON QPF. ON FRIDAY...EXPECT
ADDITIONAL SCATTERED SHOWERS AND STORMS AS AN UPPER TROUGH DIPS
THROUGH THE REGION IN SHARPENING NORTHWEST FLOW. THIS FORCING WILL
EXIT QUICKLY FRIDAY NIGHT FOR A DRY PERIOD CONTINUING THROUGH
SATURDAY.
LOOKING AHEAD...ADDITIONAL SCATTERED RAIN WILL BE POSSIBLE EVERY DAY
FROM SUNDAY THROUGH WEDNESDAY. PERSISTENT NORTHWEST FLOW WILL GUIDE
PERIODIC SHORT WAVE ENERGY INTO THE FORECAST AREA. CONSENSUS BLENDED
POPS OF 20-40 PERCENT ARE REASONABLE. THE OVERALL SEVERE WEATHER
THREAT THROUGH THIS PERIOD IS LOW. SLIGHTLY BELOW NORMAL
TEMPERATURES ARE EXPECTED THROUGH THE BULK OF THE LONG TERM
PERIOD...WITH HIGHS MAINLY IN THE UPPER 70S...PERHAPS OCCASIONALLY
TOUCHING THE LOWER 80S.&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1233 PM CDT WED JUN 24 2015
CONVECTION ACROSS IOWA AND CENTRAL ILLINOIS WILL SLOWLY INCREASE
IN COVERAGE THROUGH 00Z/25 AND THEN EVOLVE INTO AN ORGANIZED
THUNDERSTORM COMPLEX AFT 00Z/25. VFR CONDITIONS ARE EXPECTED TO
CONTINUE THROUGH 00Z/25 WITH SPOTTY MVFR/IFR CONDITIONS IN
SHRA/TSRA. AFT 00Z/25 CONDITIONS WILL SLOWLY DETERIORATE TO MVFR
AS THE THUNDERSTORM COMPLEX DEVELOPS. PERIODS OF IFR CONDITIONS
ARE POSSIBLE IF A STRONGER STORM AFFECTS A TAF SITE.
&&
.HYDROLOGY...
ISSUED AT 305 PM CDT WED JUN 24 2015
ANOTHER ROUND OF HEAVY RAIN WILL BE SEEN ACROSS THE AREA FROM LATE
THIS AFTERNOON INTO THURSDAY MORNING. SOILS ACROSS THE AREA ARE
ALREADY QUITE MOIST AND THIS ADDITIONAL RAINFALL WILL QUICKLY
SATURATE THE SOILS. AREA RIVERS ARE ALREADY RUNNING HIGH FROM
HEAVY RAINFALL OVER THE PAST 10 DAYS AND SOME ARE IN FLOOD. THIS
ADDITIONAL RAIN WILL RESULT IN ADDITIONAL RISES...SOME POSSIBLY
SIGNIFICANT...ON AREA RIVERS AND INCREASE THE FLOOD THREAT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR BENTON-BUCHANAN-
CEDAR-CLINTON-DELAWARE-DES MOINES-DUBUQUE-HENRY IA-IOWA-
JACKSON-JEFFERSON-JOHNSON-JONES-KEOKUK-LEE-LINN-LOUISA-
MUSCATINE-SCOTT-VAN BUREN-WASHINGTON.
IL...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR BUREAU-CARROLL-
HANCOCK-HENDERSON-HENRY IL-JO DAVIESS-MCDONOUGH-MERCER-
PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE.
MO...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR CLARK-SCOTLAND.
&&
$$
SYNOPSIS...08
SHORT TERM...08
LONG TERM...RP KINNEY
AVIATION...08
HYDROLOGY...08
AREA FORECAST DISCUSSION
NWS GOODLAND KS
225 PM MDT WED JUN 24 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 206 PM MDT WED JUN 24 2015
MAIN PROBLEM IS WHERE THE FRONT CURRENTLY WAFFLING BACK AND FORTH
OVER OUR AREA IS GOING TO GO AND HOW FAST. INITIALLY THE FRONT
CAME FURTHER SOUTH FASTER THAN ANYTHING DEPICTED. THE LAST FEW
HOURS IT HAS STALLED NEAR A BURLINGTON TO GOODLAND TO OBERLIN TO
NORTON LINE. BOUNDARY IS FORECAST TO SLOWLY SAG SOUTH THROUGH
TOMORROW. MODELS...ESPECIALLY THE LARGE SCALE OUTPUT...NOT DOING
WELL WITH THE FRONT POSITION. THE RAP IS THE CLOSEST TO REALITY
RIGHT NOW.
FOR TONIGHT...700 MB TEMPERATURES ARE LESS BUT STILL NEAR PLUS 15.
SOME WEAK SHORTWAVE ENERGY IS OVER THE SOUTHEAST PORTION NEAREST
THE FRONT WITH ANOTHER SHORTWAVE TROUGH MOVING IN FROM THE WEST
DURING THE EVENING. SO GOING BY ABOVE REASONING WHICH MATCHES WHAT
THE RAP IS SHOWING...ISOLATED CONVECTION DEVELOPS ALONG AND JUST
TO THE EAST OF THE FRONTAL BOUNDARY. THIS CONVECTION GOES THROUGH
ROUGHLY MID EVENING. BELIEVE THAT THUNDERSTORMS WILL MOVE IN FROM
THE WEST MUCH LIKE LAST NIGHT. MODELS DO NOT SHOW THEM MAKING IT
VERY FAR INTO THE FORECAST AREA. THINK THAT THEY WILL MAKE FURTHER
THAN INDICATED AND THIS WILL NEED TO BE WATCHED. WENT AHEAD AND
HAVE SLIGHT CHANCE TO LOW CHANCE POPS FOR TONIGHT.
FOR THURSDAY...MODELS VERY SLOW IN MOVING THE FRONT SOUTH. NOT
SURE HOW FAR SOUTH IT WILL GO/WHERE IT WILL BE SINCE THE MODEL
OUTPUT IS SO POOR RIGHT NOW. NAM STILL DOES NOT HAVE IT THROUGH
THE AREA BY LATE TOMORROW. OTHER OUTPUT HAS IT JUST SOUTH OF THE
AREA. DO HAVE HAVE LOW LEVEL UPSLOPE BUT NOT A LOT OF FORCING IN
THE MID AND UPPER LEVELS. SINCE AM NOT SURE OF THE FINAL FRONTAL
POSITION AND THE POSSIBILITY OF A WEAK SHORTWAVE AFFECTING THE
AREA JUST HAVE SLIGHT POPS IN THE AFTERNOON AT THIS TIME.
TEMPERATURES WILL BE COOLER BUT HOW MUCH WILL BE DETERMINED BY
FRONTAL POSITION. WENT NEAR TO SLIGHTLY BELOW GUIDANCE AT THIS
TIME.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 225 PM MDT WED JUN 24 2015
THURSDAY NIGHT...MODELS CONTINUE TO SHOW POTENTIAL FOR THUNDERSTORM
INITIATION ALONG FRONTAL ZONE ACROSS THE SOUTHERN PART OF OUR CWA.
WITH LIMITING FORCING ALOFT I AM NOT SURE WHAT COVERAGE WILL
INITIALLY LOOK LIKE EARLY IN THE EVENING. INCREASING MOISTURE
FLUX/MODERATE INSTABILITY...AND PEAK HEIGHT FALLS/FORCING WILL OCCUR
LATER IN THE EVENING WITH SHORTWAVE TROUGH ROTATING INTO THE REGION
FROM THE NORTHERN PLAINS. THUNDERSTORM COMPLEX MAY DEVELOP OVER
NORTH CENTRAL NEBRASKA AND MOVE SOUTH INTO OUR CWA. TRACK WILL BE
DEPENDENT ON MAIN INSTABILITY AXIS/FRONT POSITION...HOWEVER THIS
SHOULD GENERALLY REMAIN ACROSS THE NORTH/NORTHEAST HALF OF THE CWA.
CONSIDERING THE VERY MOIST AIR MASS IN PLACE I COULD SEE LOCALLY
HEAVY RAINFALL...THOUGH SLOWEST STORMS WOULD BE ALONG FRONTAL ZONE
EARLY IN THE EVENING AS GUIDANCE SEEMS TO FAVOR A MORE PROGRESSIVE
FLOW LATER IN THE EVENING WHEN BETTER COVERAGE IS EXPECTED. MODERATE
INSTABILITY A GOOD EFFECTIVE SHEER WILL ALSO SUPPORT DAMAGING
WIND/SEVERE HAIL THREAT...PARTICULARLY WITH THUNDERSTORM COMPLEX
LATER IN THE EVENING.
FRIDAY-FRIDAY NIGHT...H5 RIDGE WILL BEGIN TO AMPLIFY WITH TROUGH
DEEPENING AS IT SLIDES EAST. MOISTURE ADVECTION/ LINGERING
INSTABILITY MAY ALLOW FOR FURTHER THUNDERSTORM DEVELOPMENT ALONG
FRONTAL ZONE LINGERING THROUGH FRIDAY NIGHT. LARGE SCALE FORCING
WILL BE LIMITED TO THE NORTHEAST...AND WITH SUBSIDENCE LIKELY
SPREADING INTO THE REGION FROM THE NORTHWEST FRIDAY AFTERNOON-FRIDAY
NIGHT. I KEPT POPS LIMITED TO 20...SINCE I AM NOT VERY CONFIDENT IN
MEASURABLE PRECIP DURING THESE PERIODS.
SATURDAY-WEDNESDAY...H5 RIDGE CONTINUES TO AMPLIFY OVER THE WESTERN
US WITH OMEGA BLOCK PATTERN EVENTUALLY ESTABLISHING ITSELF THROUGH
THE REMAINING EXTENDED PERIOD. THIS KEEPS AMPLIFIED NW FLOW IN PLACE
ACROSS THE PLAINS WITH PRIMARY STORM TRACK WELL OUTSIDE OF CWA.
MODELS SHOW LEE TROUGH ATTEMPTING TO REESTABLISH ITSELF WITH
SHORTWAVES ALONG THE MISSISSIPPI RIVER VALLEY OCCASIONAL KICKING
BACKDOOR FRONTS TOWARDS THE WESTERN PLAINS. TREND WILL BE TOWARDS
PRIMARILY DRY CONDITIONS AND NEAR SEASONAL HIGHS MOST PERIODS.
GUIDANCE IS SHOWING A LITTLE BIT BETTER PRECIP SIGNAL FROM THE ECMWF
WITH SHORTWAVE PASSAGE OVER OUR CWA TUESDAY AFTERNOON-TUESDAY
NIGHT...AS GFS/GEFS SHOWS LOWERING HEIGHTS ALOFT WITH RIDGE
FLATTENING SLIGHTLY. THERE ISN`T A LOT OF CONSISTENCY BETWEEN
MODELS...SO I LIMITED POPS TO 20/30. TUESDAY IS ALSO THE DAY WITH
THE LARGEST TEMP SPREAD ALOFT/AT THE SURFACE WITH GFS POSSIBLY
SUPPORTING NEAR 100F AND ECMWF CLOSER TO THE LOW/MID 90S. I KEPT MID-
UPPER 90S INHERITED FROM WEIGHTED BLEND CONSIDERING THE RANGE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1133 AM MDT WED JUN 24 2015
VERY LOW CONFIDENCE AND UNCERTAIN FORECAST DUE TO POOR MODEL
PERFORMANCE IN THE HANDLING THE FRONT CURRENTLY OVER OUR AREA. RAP
MODEL IS THE CLOSEST BUT IT STILL IS NOT FAR ENOUGH SOUTH. USED
THE RAP FOR THE WIND FORECAST THEN BLENDED IN THE OTHER MODEL
OUTPUT THAT FITS IN WITH THE RAP SCENARIO. AT THIS TIME THINK ANY
THUNDERSTORMS WILL DEVELOP TO THE EAST AND SOUTH OF BOTH SITES.
FOR MOST OF THE PERIOD EXPECT VFR CONDITIONS. HOWEVER MVFR
CONDITIONS WILL BE POSSIBLE AFTER 06Z...ESPECIALLY WITH THE
CEILINGS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...DR
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
220 PM MDT WED JUN 24 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 206 PM MDT WED JUN 24 2015
MAIN PROBLEM IS WHERE THE FRONT CURRENTLY WAFFLING BACK AND FORTH
OVER OUR AREA IS GOING TO GO AND HOW FAST. INITIALLY THE FRONT
CAME FURTHER SOUTH FASTER THAN ANYTHING DEPICTED. THE LAST FEW
HOURS IT HAS STALLED NEAR A BURLINGTON TO GOODLAND TO OBERLIN TO
NORTON LINE. BOUNDARY IS FORECAST TO SLOWLY SAG SOUTH THROUGH
TOMORROW. MODELS...ESPECIALLY THE LARGE SCALE OUTPUT...NOT DOING
WELL WITH THE FRONT POSITION. THE RAP IS THE CLOSEST TO REALITY
RIGHT NOW.
FOR TONIGHT...700 MB TEMPERATURES ARE LESS BUT STILL NEAR PLUS 15.
SOME WEAK SHORTWAVE ENERGY IS OVER THE SOUTHEAST PORTION NEAREST
THE FRONT WITH ANOTHER SHORTWAVE TROUGH MOVING IN FROM THE WEST
DURING THE EVENING. SO GOING BY ABOVE REASONING WHICH MATCHES WHAT
THE RAP IS SHOWING...ISOLATED CONVECTION DEVELOPS ALONG AND JUST
TO THE EAST OF THE FRONTAL BOUNDARY. THIS CONVECTION GOES THROUGH
ROUGHLY MID EVENING. BELIEVE THAT THUNDERSTORMS WILL MOVE IN FROM
THE WEST MUCH LIKE LAST NIGHT. MODELS DO NOT SHOW THEM MAKING IT
VERY FAR INTO THE FORECAST AREA. THINK THAT THEY WILL MAKE FURTHER
THAN INDICATED AND THIS WILL NEED TO BE WATCHED. WENT AHEAD AND
HAVE SLIGHT CHANCE TO LOW CHANCE POPS FOR TONIGHT.
FOR THURSDAY...MODELS VERY SLOW IN MOVING THE FRONT SOUTH. NOT
SURE HOW FAR SOUTH IT WILL GO/WHERE IT WILL BE SINCE THE MODEL
OUTPUT IS SO POOR RIGHT NOW. NAM STILL DOES NOT HAVE IT THROUGH
THE AREA BY LATE TOMORROW. OTHER OUTPUT HAS IT JUST SOUTH OF THE
AREA. DO HAVE HAVE LOW LEVEL UPSLOPE BUT NOT A LOT OF FORCING IN
THE MID AND UPPER LEVELS. SINCE AM NOT SURE OF THE FINAL FRONTAL
POSITION AND THE POSSIBILITY OF A WEAK SHORTWAVE AFFECTING THE
AREA JUST HAVE SLIGHT POPS IN THE AFTERNOON AT THIS TIME.
TEMPERATURES WILL BE COOLER BUT HOW MUCH WILL BE DETERMINED BY
FRONTAL POSITION. WENT NEAR TO SLIGHTLY BELOW GUIDANCE AT THIS
TIME.
.LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 302 AM MDT
WED JUN 24 2015
AT THE BEGINNING OF THE EXTENDED PERIOD MODELS ARE SHOWING THE
LONGWAVE PATTERN AMPLIFYING THROUGH THE END OF THE PERIOD. A
STRONG UPPER RIDGE IS LOCATED TO OUR WEST ALONG THE ROCKIES AND
EXTENDING WELL INTO WESTERN CANADA. AT THE SAME TIME A DEEPENING
TROUGH IS LOCATED OVER THE GREAT LAKES REGION AND EXTENDING IN THE
SOUTHEASTERN U.S. THIS PATTERN SETS UP A PREDOMINANTLY
NORTHWESTERLY UPPER FLOW OVER THE TRI STATE AREA. ON THE SURFACE
THE LOCATED AREA WILL BE UNDER THE INFLUENCE OF A HIGH PRESSURE
CENTER TO THE WEST OF THE CWA.
THERE IS A SLIGHT CHANCES OF PRECIPITATION... MOSTLY IN THE FORM
OF ISOLATED AFTERNOON AND EVENING CONVECTION... ASSOCIATED WITH
THE OCCASIONAL SHORTWAVE TROUGHS THAT WILL MOVE THROUGH THE AREA
FROM THE NORTH. OTHERWISE... EXPECT A MOSTLY DRY PERIOD WITH
TEMPERATURES CLOSER TO NORMAL DUE TO THE NORTHERLY FLOW ALOFT AND
A PERSISTENT EASTERLY SURFACE WINDS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1133 AM MDT WED JUN 24 2015
VERY LOW CONFIDENCE AND UNCERTAIN FORECAST DUE TO POOR MODEL
PERFORMANCE IN THE HANDLING THE FRONT CURRENTLY OVER OUR AREA. RAP
MODEL IS THE CLOSEST BUT IT STILL IS NOT FAR ENOUGH SOUTH. USED
THE RAP FOR THE WIND FORECAST THEN BLENDED IN THE OTHER MODEL
OUTPUT THAT FITS IN WITH THE RAP SCENARIO. AT THIS TIME THINK ANY
THUNDERSTORMS WILL DEVELOP TO THE EAST AND SOUTH OF BOTH SITES.
FOR MOST OF THE PERIOD EXPECT VFR CONDITIONS. HOWEVER MVFR
CONDITIONS WILL BE POSSIBLE AFTER 06Z...ESPECIALLY WITH THE
CEILINGS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...BW
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1138 AM MDT WED JUN 24 2015
.UPDATE...
ISSUED AT 1027 AM MDT WED JUN 24 2015
COLD FRONT HAS COME MUCH FURTHER SOUTH THAN EXPECTED. COMBINATION
OF COLD OUTFLOW FROM STORMS UP NORTH AND SURFACE LOWS OVER EASTERN
COLORADO DEVELOPING DIFFERENTLY THAN WHAT THE MODELS WERE
ANTICIPATING. NOTHING IS REALLY CATCHING THIS RIGHT NOW WITH THE
RAP THE CLOSEST. HOWEVER...IT STILL IS NOT FAR ENOUGH SOUTH.
ALSO SOME WEAK THUNDERSTORM DEVELOPMENT HAS OCCURRED ALONG THE
FRONT. SO HAD TO UPDATE THE FORECAST FOR THE WINDS...COOLER
TEMPERATURES IN THE NORTHERN PORTION OF THE AREA...MORE CLOUD
COVER...AND A WIDER AREA AND SOONER INITIATION OF ISOLATED
THUNDERSTORMS THROUGH THIS EVENING. WILL PROBABLY NOT BE THE LAST
UPDATE.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY NIGHT)
ISSUED AT 344 AM MDT WED JUN 24 2015
FORECAST FOCUS IS ON THE POSSIBILITY OF SEVERE THUNDERSTORMS
ACROSS THE FORECAST AREA LATE THURSDAY INTO THURSDAY NIGHT.
THE UPPER LEVEL ZONAL FLOW PATTERN ACROSS THE UNITED STATES
TRANSITIONS TO A MORE MERIDIONAL PATTERN THURSDAY AND THURSDAY
NIGHT. A RIDGE BUILDS OVER THE INTERMOUNTAIN WEST WHILE A TROUGH
DEEPENS IN THE LEE OF THE ROCKIES AND OVER THE PLAINS STATES WITH
THE PATTERN BECOMING MORE HIGHLY AMPLIFIED ON FRIDAY AND FRIDAY
NIGHT.
THE INITIAL SHORT WAVE TROUGH MOVING THROUGH THE WESTERLY FLOW
ALOFT ACROSS THE NORTHERN PLAINS TODAY LIFTS A LOW CENTER OUT OF
THE LOW PRESSURE AREA IN PLACE OVER THE FORECAST AREA. A PORTION
OF THE SURFACE LOW REMAINS ANCHORED OVER THE CENTRAL HIGH PLAINS
AND MOVES FURTHER SOUTH OVER THE PANHANDLE REGION THURSDAY AND
THURSDAY NIGHT ALONG WITH THE FRONTAL BOUNDARY AS HIGH PRESSURE
MOVES INTO THE NORTHERN SECTIONS OF THE CENTRAL HIGH PLAINS. THIS
WILL BRING SOMEWHAT COOLER TEMPERATURES TO MAINLY THE NORTHERN
SECTIONS OF THE REGION ON THURSDAY. IT WILL ALSO BRING A BETTER
CHANCE OF THUNDERSTORMS TO THE REGION LATE THURSDAY INTO THURSDAY
NIGHT. THE MARGINAL TO SLIGHT RISK OF SEVERE THUNDERSTORMS ALSO
TRANSITIONS SOUTHWARD FROM THE NORTHERN PLAINS TODAY TO THE
CENTRAL PLAINS ON THURSDAY AND THE SOUTHERN PLAIN ON FRIDAY.
COOLER MORE SEASONABLE TEMPERATURES WILL REMAIN IN PLACE THROUGH
FRIDAY AND FRIDAY NIGHT.
.LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 302 AM MDT
WED JUN 24 2015
AT THE BEGINNING OF THE EXTENDED PERIOD MODELS ARE SHOWING THE
LONGWAVE PATTERN AMPLIFYING THROUGH THE END OF THE PERIOD. A
STRONG UPPER RIDGE IS LOCATED TO OUR WEST ALONG THE ROCKIES AND
EXTENDING WELL INTO WESTERN CANADA. AT THE SAME TIME A DEEPENING
TROUGH IS LOCATED OVER THE GREAT LAKES REGION AND EXTENDING IN THE
SOUTHEASTERN U.S. THIS PATTERN SETS UP A PREDOMINANTLY
NORTHWESTERLY UPPER FLOW OVER THE TRI STATE AREA. ON THE SURFACE
THE LOCATED AREA WILL BE UNDER THE INFLUENCE OF A HIGH PRESSURE
CENTER TO THE WEST OF THE CWA.
THERE IS A SLIGHT CHANCES OF PRECIPITATION... MOSTLY IN THE FORM
OF ISOLATED AFTERNOON AND EVENING CONVECTION... ASSOCIATED WITH
THE OCCASIONAL SHORTWAVE TROUGHS THAT WILL MOVE THROUGH THE AREA
FROM THE NORTH. OTHERWISE... EXPECT A MOSTLY DRY PERIOD WITH
TEMPERATURES CLOSER TO NORMAL DUE TO THE NORTHERLY FLOW ALOFT AND
A PERSISTENT EASTERLY SURFACE WINDS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1133 AM MDT WED JUN 24 2015
VERY LOW CONFIDENCE AND UNCERTAIN FORECAST DUE TO POOR MODEL
PERFORMANCE IN THE HANDLING THE FRONT CURRENTLY OVER OUR AREA. RAP
MODEL IS THE CLOSEST BUT IT STILL IS NOT FAR ENOUGH SOUTH. USED
THE RAP FOR THE WIND FORECAST THEN BLENDED IN THE OTHER MODEL
OUTPUT THAT FITS IN WITH THE RAP SCENARIO. AT THIS TIME THINK ANY
THUNDERSTORMS WILL DEVELOP TO THE EAST AND SOUTH OF BOTH SITES.
FOR MOST OF THE PERIOD EXPECT VFR CONDITIONS. HOWEVER MVFR
CONDITIONS WILL BE POSSIBLE AFTER 06Z...ESPECIALLY WITH THE
CEILINGS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...LOCKHART
LONG TERM...BW
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
304 AM MDT WED JUN 24 2015
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 154 PM MDT TUE JUN 23 2015
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS RIDGE STILL IN
PLACE ACROSS SOUTHERN PLAINS WITH WESTERLY ZONAL FLOW ACROSS THE
NORTHERN PLAINS. WEAK SHORTWAVE TROUGHS AND MONSOONAL/PACIFIC FLOW
CONTINUE TO ROTATE ALONG THE WESTERN PERIPHERY OF THE RIDGE AND
INTO THE CENTRAL ROCKIES. AT THE SURFACE STATIONARY FRONT HAS
LIFTED TO NEAR SCOTT CITY JUST SOUTH OF OUR CWA WITH STATIONARY
FRONT ALONG FRONT RANGE.
THIS AFTERNOON-TONIGHT...GUIDANCE CONTINUES TO SHOW WARM FRONT
LIFTING NORTH THROUGH THE AFTERNOON AND EVENING AS LEE TROUGH
DEEPENS. THUNDERSTORMS HAVE ALREADY DEVELOPED ACROSS SOUTH CENTRAL
COLORADO. HIGH RES GUIDANCE CONTINUES TO SHOW CAP WEAKENING
ALONG THE FRONT FROM THE WEST TO THE EAST...AND THUNDERSTORMS
EITHER DEVELOPING OR MOVING INTO THE SW PART OF THE CWA SPREADING
NORTH AND EAST THIS EVENING. WHILE PWATS AND TD VALUES ARE
IMPRESSIVE...DEEP LAYER MIXING RATIOS/MOISTURE PROFILES ARE LESS
THAN FAVORABLE FOR WIDESPREAD COVERAGE LOCALLY WITHOUT
ORGANIZATION INTO MORE OF A CLUSTER FROM THE WEST. SHORTWAVE
TROUGH ADVERTISED TO MOVE ACROSS CWA THIS EVENING COULD HELP WITH
INITIATION...SO DESPITE THE DRY LAYERS ALOFT 20 TO 30 POPS STILL
SEEMS REASONABLE. VEERING SHEER PROFILES IN THE 0-3KM LAYER COULD
HELP SUPERCELL POTENTIAL ASSUMING THUNDERSTORMS DEVELOP THIS
AFTERNOON/EARLY EVENING ALONG WARM FRONT BEFORE LOW LEVELS
STABILIZE. AS EVENING PROGRESSES PROFILES FAVOR MAINLY ELEVATED
THUNDERSTORMS...AND GOOD EFFECTIVE SHEER VALUES SHOULD STILL
SUPPORT LARGE HAIL/DAMAGING WIND THREAT WITH ANY ONGOING ACTIVITY.
WEDNESDAY...WARM FRONT STALLS NEAR THE KS/NE BORDER EARLY WEDNESDAY
MORNING WITH MOISTURE POOLING NORTH OF THIS FRONT EARLY WEDNESDAY
MORNING WHEN FOG/STRATUS COULD DEVELOP. GUIDANCE STILL SHOWING A
POTENTIAL BUT I AM STILL NOT SURE VIS WILL BE LOW ENOUGH TO INCLUDE
MENTION IN FORECAST...SO WILL MONITOR SHORT RANGE
GUIDANCE/TRENDS. FRONT SETS UP ROUGHLY THROUGH THE CENTRAL PART OF
THE CWA AS SURFACE LOW SHIFTS EAST WEDNESDAY AFTERNOON...WITH NEAR
100F TEMPS SOUTH OF THIS FRONT AND IN THE 90S TO THE NW. THIS
FRONT WILL ACT AS A FOCUS FOR POSSIBLY THUNDERSTORM DEVELOPMENT IN
THE AFTERNOON...AGAIN AIDED BY HEIGHT FALLS FROM WEAK SHORTWAVE
ROTATING INTO THE REGION FROM THE WEST. I KEPT 20 POPS CONFINED TO
THE SW IN THE AFTERNOON...THOUGH DEPENDING ON CAP STRENGTH I COULD
SEE A ISOLATED THUNDERSTORM FURTHER EAST. NOT A STRONG SIGNAL IN
THE AFTERNOON FURTHER EAST..SO I FAVOR STICKING WITH A
CONSERVATIVE APPROACH FOR NOW.
.LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 302 AM MDT
WED JUN 24 2015
AT THE BEGINNING OF THE EXTENDED PERIOD MODELS ARE SHOWING THE
LONGWAVE PATTERN AMPLIFYING THROUGH THE END OF THE PERIOD. A
STRONG UPPER RIDGE IS LOCATED TO OUR WEST ALONG THE ROCKIES AND
EXTENDING WELL INTO WESTERN CANADA. AT THE SAME TIME A DEEPENING
TROUGH IS LOCATED OVER THE GREAT LAKES REGION AND EXTENDING IN THE
SOUTHEASTERN U.S. THIS PATTERN SETS UP A PREDOMINANTLY
NORTHWESTERLY UPPER FLOW OVER THE TRI STATE AREA. ON THE SURFACE
THE LOCATED AREA WILL BE UNDER THE INFLUENCE OF A HIGH PRESSURE
CENTER TO THE WEST OF THE CWA.
THERE IS A SLIGHT CHANCES OF PRECIPITATION... MOSTLY IN THE FORM
OF ISOLATED AFTERNOON AND EVENING CONVECTION... ASSOCIATED WITH
THE OCCASIONAL SHORTWAVE TROUGHS THAT WILL MOVE THROUGH THE AREA
FROM THE NORTH. OTHERWISE... EXPECT A MOSTLY DRY PERIOD WITH
TEMPERATURES CLOSER TO NORMAL DUE TO THE NORTHERLY FLOW ALOFT AND
A PERSISTENT EASTERLY SURFACE WINDS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1027 PM MDT TUE JUN 23 2015
CURRENT RADAR AND STORM TRENDS INDICATE INCREASING CHANCES THAT A
STORM WILL MOVE INTO KMCK NEAR THE BEGINNING OF THIS FORECAST. A
VICINITY THUNDERSTORM CANNOT BE RULED OUT NEAR KGLD AS WELL.
OVERNIGHT STORMS WILL WEAKEN AND DISSIPATE. FORECAST SOUNDINGS
INDICATE STRATUS AT KMCK TOWARD SUNRISE AND THEN BREAKING OUT
AROUND 15Z. CONDITIONS MAY GET CLOSE TO MVFR AT KMCK. DURING THE
DAY WEDNESDAY, EXPECT VFR CONDITIONS AT BOTH SITES WITH A SLIGHT
CHANCE OF THUNDERSTORMS NEAR KGLD DURING THE EVENING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...BW
AVIATION...FS
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
152 AM CDT WED JUN 24 2015
...UPDATE TO LONG TERM...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 132 AM CDT WED JUN 24 2015
EARLY MORNING CONVECTION NORTH OF THE I-70 CORRIDOR RELATED WELL
WITH WHERE 850MB WARM AIR CONVECTION, LOCATED NEAR THE NOSE OF A
50KT 850MB JET, WAS OCCURRING JUST NORTH OF THE 700MB 12C TO 14C
BAROCLINIC ZONE. THIS WAS ALSO JUST NORTH OF A SURFACE BOUNDARY
WHICH EXTENDED FROM WEST TO EAST ACROSS NORTH CENTRAL KANSAS. THE
RAP AND NAM WERE BOTH IN GOOD AGREEMENT EARLY THIS MORNING WITH
KEEPING THIS CONVECTION NORTH OF ELLIS AND TREGO COUNTIES AS THESE
THUNDERSTORMS WEAKEN DURING THE EARLY MORNING HOURS. AT THIS TIME
WILL LEAN TOWARDS NOT INSERTING ANY MENTION OF EARLY MORNING
CONVECTION IN THE HAYS OR WAKEENEY AREAS, HOWEVER WILL CONTINUE TO
MONITOR THE ONGOING CONVECTION GIVEN THE DEVELOPING NORTHWEST TO
SOUTHEAST ORIENTATION OF THE 700MB BAROCLINIC ZONE DURING THE
PREDAWN HOURS.
THE WEST TO EAST SURFACE FRONTAL BOUNDARY WILL MOVE NORTH ACROSS
NORTHWEST AND NORTH CENTRAL KANSAS TODAY AS AN UPPER HIGH SHIFTS
SLOWLY NORTH OUT OF NORTHERN OKLAHOMA INTO SOUTHERN KANSAS. THE
WARM 700MB TEMPERATURE THAT WAS LOCATED OVER SOUTHWEST KANSAS AT
00Z WEDNESDAY WILL ALSO LIFT SLOWLY NORTH AND BY 00Z THURSDAY
THESE WARM 700MB TEMPERATURES WILL EXTEND FROM EAST CENTRAL
COLORADO INTO NORTH CENTRAL KANSAS. 850MB NET 24 HOUR TEMPERATURE
TRENDS ACROSS SOUTHWEST KANSAS WILL CHANGE VERY LITTLE BETWEEN 00Z
THURSDAY TO 00Z FRIDAY AS THE 700MB TEMPERATURES COOL BY A COUPLE
OF DEGREES NEAR THE OKLAHOMA BORDER. BASED ON THESE TEMPERATURE
TRENDS AND A MIXING DEPTH OF 800MB WILL STAY CLOSE TO THE PREVIOUS
FORECAST WITH HIGHS RANGING FROM THE MID 90S IN SOUTH CENTRAL
KANSAS TO AROUND 100 DEGREES ACROSS WEST CENTRAL AND NORTH CENTRAL
KANSAS.
CONVECTION LATE THURSDAY SHOULD BE CONFINED NEAR A SURFACE TROUGH
OF LOW PRESSURE THAT WILL BE LOCATED WEST OF THE COLORADO BORDER
AS A WEAK UPPER LEVEL TROUGH EXITS THE ROCKIES AND BEGINS TO CROSS
THE CENTRAL HIGH PLAINS. 21Z THURSDAY AND 00Z FRIDAY CAPE VALUES
FROM THE NAM INDICATED THAT THE INSTABILITY AXIS OF 2000 TO 3000
J/KG WILL STRETCH FROM EASTERN COLORADO INTO NORTHWEST KANSAS LATE
DAY AND EARLY THIS EVENING WITH A 20 KNOT 0-6KM SHEAR. WIDELY
SCATTERED THUNDERSTORMS WILL BE POSSIBLE IN THIS REGION LATE DAY
BUT THESE STORMS ARE EXPECTED WEAKEN/DISSIPATE AS THEY MOVE EAST
INTO A MORE STABLE AIR MASS AFTER SUNSET.
TEMPERATURES TONIGHT WILL BE SIMILAR AS THE LOWS EARLY THIS
MORNING GIVEN A SOUTHERLY WIND AT AROUND 15 MPH, HIGH CLOUDS
SPREADING INCREASING ACROSS WEST CENTRAL/NORTH CENTRAL KANSAS
AFTER MIDNIGHT, AND EARLY MORNING DEWPOINTS IN THE UPPER 50S TO
LOWER 60S.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 150 AM CDT WED JUN 24 2015
PRECIP CHANCES PICK UP LATE THIS WEEK AS MEDIUM RANGE MODELS
INDICATE A NORTHWEST FLOW ALOFT DEVELOPING ACROSS THE WESTERN HIGH
PLAINS LATE THURSDAY WHILE AN UPPER LEVEL RIDGE OF HIGH PRESSURE
BUILDS ACROSS THE GREAT BASIN. MEANWHILE, THE GFS AND ECWMF
CONTINUE TO SHOW A SERIES OF H5 VORT MAXIMA COMING OFF THE
AMPLIFYING RIDGE AXIS AND DIGGING SOUTHEAST OUT OF THE NORTHERN
ROCKIES INTO THE PLAINS OF SOUTH DAKOTA AND NEBRASKA. AN ATTENDANT
COLD FRONT IS PROJECTED TO PUSH SOUTHWARD INTO WESTERN KANSAS
SOMETIME THURSDAY NIGHT/EARLY FRIDAY PROVIDING THE FOCUS FOR
POTENTIAL THUNDERSTORMS ACROSS PORTIONS OF CENTRAL AND WESTERN
KANSAS. THE NORTHWEST FLOW ALOFT WILL INCREASE SOME AS AN UPPER
LEVEL JET CRESTING THE RIDGE AXIS OUT WEST, DIGS SOUTHEAST INTO
THE SOUTHERN DAKOTAS AND NEBRASKA. ALONG WITH AMPLE LOW/MID LEVEL
MOISTURE AND INSTABILITY PRESENT, THE POTENTIAL FOR THUNDERSTORMS
WILL INCREASE THURSDAY NIGHT INTO FRIDAY. THUNDERSTORM CHANCES
WILL LESSEN SATURDAY AS THE UPPER LEVEL RIDGE CONTINUES TO AMPLIFY
OUT WEST WHILE THE AFOREMENTIONED COLD FRONT PUSHES FURTHER SOUTH
INTO NORTH TEXAS. THERE IS AN OUTSIDE SHOT AT ISOLATED THUNDERSTORMS
COMING OFF THE ROCKIES WITHIN A SOUTHEASTERLY UPSLOPE FLOW AND
POTENTIALLY DRIFTING INTO EXTREME SOUTHWEST KANSAS SATURDAY
EVENING.
SEASONAL TEMPERATURES WILL CONTINUE THURSDAY EVEN AS A WEAK COLD
FRONT/TROUGH AXIS BEGINS PUSHING INTO NORTHWEST AND NORTH CENTRAL
KANSAS. SO LOOK FOR HIGHS BACK UP INTO THE 90S(F) ACROSS MUCH OF
CENTRAL AND SOUTHWEST KANSAS THURSDAY AFTERNOON. THE COLD FRONT
WILL PUSH FURTHER SOUTH ACROSS SOUTHWEST AND CENTRAL KANSAS INTO
OKLAHOMA LATE THURSDAY NIGHT ALLOWING SLIGHTLY COOLER AIR TO
FILTER SOUTHWARD INTO THE AREA. THIS WILL LOWER HIGHS TO ONLY THE
80S(F) FRIDAY AFTERNOON. HIGHS WILL GRADUALLY REBOUND THROUGHOUT
THE WEEKEND AS A LOW LEVEL SOUTH TO SOUTHEASTERLY FLOW RETURNS TO
WESTERN KANSAS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1201 AM CDT WED JUN 24 2015
VFR CONDITIONS ARE EXPECTED OVERNIGHT AS ONLY MID AND HIGH LEVEL
MOISTURE PRECEDES AN UPPER LEVEL TROUGH AS IT CROSSES WESTERN
KANSAS. AS THIS UPPER LEVEL DISTURBANCE PASSES SKIES WILL CLEAR
FROM WEST TO EAST EARLY THURSDAY MORNING. SOUTH TO SOUTHWEST WINDS
OVERNIGHT WILL BE AT 10 TO 15 KNOTS. RAP AND NAM WERE SIMILAR WITH
HAVING A 50 KNOT LOW LEVEL JET ACROSS SOUTHWEST KANSAS BETWEEN
06Z AND 12Z. THIS JET AXIS APPEARS TO BE LOCATED NEAR AND WEST OF
GCK AND HYS SO WILL INSERT AS WIND SHEAR GROUP INTO THESE TAFS
THROUGH 12Z THURSDAY. BY LATE MORNING THESE SOUTHERLY WINDS
INCREASE INTO THE 20 TO NEAR 25 KNOTS RANGE AS STRONGER WINDS
LOCATED IN THE 900MB TO 850MB LEVEL BEGIN TO MIX DOWN TO THE
SURFACE. THESE GUSTY WINDS WILL THEN CONTINUE THROUGH THE
REMAINDER OF THE AFTERNOON.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 97 71 96 67 / 0 0 30 30
GCK 98 71 95 65 / 0 10 30 30
EHA 95 69 95 65 / 0 0 30 30
LBL 96 70 97 67 / 0 0 30 30
HYS 100 73 92 65 / 10 10 30 40
P28 98 73 97 70 / 0 0 30 30
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...JJOHNSON
AVIATION...BURGERT
AREA FORECAST DISCUSSION...CORRECTED
NWS DODGE CITY KS
136 AM CDT WED JUN 24 2015
...UPDATED SHORT TERM DISCUSSION
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 132 AM CDT WED JUN 24 2015
EARLY MORNING CONVECTION NORTH OF THE I-70 CORRIDOR RELATED WELL
WITH WHERE 850MB WARM AIR CONVECTION, LOCATED NEAR THE NOSE OF A
50KT 850MB JET, WAS OCCURRING JUST NORTH OF THE 700MB 12C TO 14C
BAROCLINIC ZONE. THIS WAS ALSO JUST NORTH OF A SURFACE BOUNDARY
WHICH EXTENDED FROM WEST TO EAST ACROSS NORTH CENTRAL KANSAS. THE
RAP AND NAM WERE BOTH IN GOOD AGREEMENT EARLY THIS MORNING WITH
KEEPING THIS CONVECTION NORTH OF ELLIS AND TREGO COUNTIES AS THESE
THUNDERSTORMS WEAKEN DURING THE EARLY MORNING HOURS. AT THIS TIME
WILL LEAN TOWARDS NOT INSERTING ANY MENTION OF EARLY MORNING
CONVECTION IN THE HAYS OR WAKEENEY AREAS, HOWEVER WILL CONTINUE TO
MONITOR THE ONGOING CONVECTION GIVEN THE DEVELOPING NORTHWEST TO
SOUTHEAST ORIENTATION OF THE 700MB BAROCLINIC ZONE DURING THE
PREDAWN HOURS.
THE WEST TO EAST SURFACE FRONTAL BOUNDARY WILL MOVE NORTH ACROSS
NORTHWEST AND NORTH CENTRAL KANSAS TODAY AS AN UPPER HIGH SHIFTS
SLOWLY NORTH OUT OF NORTHERN OKLAHOMA INTO SOUTHERN KANSAS. THE
WARM 700MB TEMPERATURE THAT WAS LOCATED OVER SOUTHWEST KANSAS AT
00Z WEDNESDAY WILL ALSO LIFT SLOWLY NORTH AND BY 00Z THURSDAY
THESE WARM 700MB TEMPERATURES WILL EXTEND FROM EAST CENTRAL
COLORADO INTO NORTH CENTRAL KANSAS. 850MB NET 24 HOUR TEMPERATURE
CHANGE ACROSS SOUTHWEST KANSAS WILL CHANGE VERY LITTLE BETWEEN
00Z WEDNESDAY TO 00Z THURSDAY AS THE 700MB TEMPERATURES COOL BY A
COUPLE OF DEGREES NEAR THE OKLAHOMA BORDER. BASED ON THESE
TEMPERATURE TRENDS AND A MIXING DEPTH OF 800MB WILL STAY CLOSE TO
THE PREVIOUS FORECAST WITH HIGHS RANGING FROM THE MID 90S IN SOUTH
CENTRAL KANSAS TO AROUND 100 DEGREES ACROSS WEST CENTRAL AND NORTH
CENTRAL KANSAS.
CONVECTION LATE WEDNESDAY SHOULD BE CONFINED NEAR A SURFACE
TROUGH OF LOW PRESSURE THAT WILL BE LOCATED WEST OF THE COLORADO
BORDER AS A WEAK UPPER LEVEL TROUGH EXITS THE ROCKIES AND BEGINS
TO CROSS THE CENTRAL HIGH PLAINS. 21Z WEDNESDAY AND 00Z THURSDAY CAPE
VALUES FROM THE NAM INDICATED THAT THE INSTABILITY AXIS OF 2000 TO
3000 J/KG WILL STRETCH FROM EASTERN COLORADO INTO NORTHWEST KANSAS
LATE DAY AND EARLY THIS EVENING WITH A 20 KNOT 0-6KM SHEAR. WIDELY
SCATTERED THUNDERSTORMS WILL BE POSSIBLE IN THIS REGION LATE DAY
BUT THESE STORMS ARE EXPECTED WEAKEN/DISSIPATE AS THEY MOVE EAST
INTO A MORE STABLE AIR MASS AFTER SUNSET.
TEMPERATURES TONIGHT WILL BE SIMILAR AS THE LOWS EARLY THIS
MORNING GIVEN A SOUTHERLY WIND AT AROUND 15 MPH, HIGH CLOUDS
SPREADING INCREASING ACROSS WEST CENTRAL/NORTH CENTRAL KANSAS
AFTER MIDNIGHT, AND EARLY MORNING DEWPOINTS IN THE UPPER 50S TO
LOWER 60S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 201 PM CDT TUE JUN 23 2015
ECMWF SHOWS SOME CONVECTION DEVELOPING ACROSS THE EASTERN ZONES
THURSDAY EVENING. THIS MATCHES THE TAIL END OF THE 4 KM NAM.
WILL HAVE CHANCE POPS HERE AND SLIGHT POPS TO THE WEST. WIND AND
HAIL MAY BE POSSIBLE WITH THIS ACTIVITY AS THERE IS LOW END SHEAR
AND MODERATE CAPE. LOWS WILL BE MORE MILD FOR FAR WESTERN KANSAS
FRIDAY MORNING AS COOLER AIR ADVECTS IN. SPEAKING OF, HIGHS FRIDAY
WILL BE COOLER WITH 80S INSTEAD OF 90S POST FRONTAL. LOWS IN THE
60S ARE EXPECTED FOR SATURDAY MORNING. ANOTHER DAY WITH A BREAK IN
THE HEAT IS EXPECTED FOR SATURDAY WITH HIGHS IN THE 80S AGAIN. FOR
NEXT WEEK, THE WARM SECTOR WILL LIFT NORTHWARD WITH 90S RETURNING.
THE REALLY INTENSE HEAT LOOKS TO REMAIN WEST OF HERE AS THE RIDGE
AMPLIFIES OUT WEST AND NORTHERLY FLOW DEVELOPS ACROSS KANSAS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1201 AM CDT WED JUN 24 2015
VFR CONDITIONS ARE EXPECTED OVERNIGHT AS ONLY MID AND HIGH LEVEL
MOISTURE PRECEDES AN UPPER LEVEL TROUGH AS IT CROSSES WESTERN
KANSAS. AS THIS UPPER LEVEL DISTURBANCE PASSES SKIES WILL CLEAR
FROM WEST TO EAST EARLY THURSDAY MORNING. SOUTH TO SOUTHWEST WINDS
OVERNIGHT WILL BE AT 10 TO 15 KNOTS. RAP AND NAM WERE SIMILAR WITH
HAVING A 50 KNOT LOW LEVEL JET ACROSS SOUTHWEST KANSAS BETWEEN
06Z AND 12Z. THIS JET AXIS APPEARS TO BE LOCATED NEAR AND WEST OF
GCK AND HYS SO WILL INSERT AS WIND SHEAR GROUP INTO THESE TAFS
THROUGH 12Z THURSDAY. BY LATE MORNING THESE SOUTHERLY WINDS
INCREASE INTO THE 20 TO NEAR 25 KNOTS RANGE AS STRONGER WINDS
LOCATED IN THE 900MB TO 850MB LEVEL BEGIN TO MIX DOWN TO THE
SURFACE. THESE GUSTY WINDS WILL THEN CONTINUE THROUGH THE
REMAINDER OF THE AFTERNOON.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 97 71 96 68 / 0 0 20 30
GCK 98 71 95 66 / 0 10 20 20
EHA 98 69 95 66 / 0 0 20 20
LBL 97 70 97 68 / 0 0 20 20
HYS 100 73 92 66 / 10 10 40 40
P28 97 73 97 71 / 0 0 20 40
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...99
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1204 AM CDT WED JUN 24 2015
...UPDATED SYNOPSIS AND AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 1201 AM CDT WED JUN 24 2015
AT 00Z WEDNESDAY A 500MB HIGH EXTENDED FROM NEAR THE FOUR CORNERS
REGION TO EASTERN OKLAHOMA NORTH OF THIS UPPER HIGH A WESTERLY
FLOW EXTENDED FROM THE ROCKIES TO THE MISSISSIPPI VALLEY. WATER
VAPOR LOOP AND 00Z WEDNESDAYS UPPER AIR ANALYSIS INDICATED SEVERAL
WEAK UPPER LEVEL TROUGH EMBEDDED IN THIS WESTERLY FLOW. OVER THE
CENTRAL HIGH PLAINS A SURFACE WARM FRONT EXTENDED FROM AN AREA OF
LOW PRESSURE OVER CENTRAL COLORADO TO EAST CENTRAL KANSAS. 850MB
TEMPERATURES EARLIER THIS EVENING INDICATED A BAROCLINIC ZONE
STRETCHED FROM WESTERN NEBRASKA TO NORTH EASTERN KANSAS AND
TEMPERATURES ACROSS THIS BAROCLNIC ZONE RANGE FROM +26C AT DODGE
CITY TO +14C AT OMAHA. 700MB TEMPERATURES VARIED FROM +12C AT
TOPEKA TO +16C AT DODGE CITY TO +17C AT DENVER.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 324 PM CDT TUE JUN 23 2015
A DRY FORECAST WILL CONTINUE TONIGHT THROUGH WEDNESDAY AS AN
EAST-WEST ORIENTED MID-UPPER TROPOSPHERIC ANTICYCLONE WILL
BASICALLY REMAIN UNCHANGED THROUGH WEDNESDAY. WE WILL CONTINUE TO
SEE STRONG FAIRLY STRONG DIURNAL WINDS ON WEDNESDAY, MUCH LIKE
TODAY. THE MOST INTENSE THERMAL RIDGE WILL BE FROM WEST CENTRAL
INTO NORTHWEST KANSAS ON WEDNESDAY, AND THIS WILL BE WHERE THE
WARMEST TEMPERATURES WILL BE IN THE FORECAST...AROUND 100 FROM
NEAR SYRACUSE NORTHEAST TO WAKEENEY-HAYS. OTHERWISE, MID TO UPPER
90S CAN BE EXPECTED ELSEWHERE. THUNDERSTORMS DEVELOPING ACROSS THE
HIGHER TERRAIN OF COLORADO LATE THIS AFTERNOON/EVENING WILL MOVE
NORTHEAST AND ARE EXPECTED TO REMAIN OUTSIDE OF THE DODGE CITY NWS
AREA OF FORECAST RESPONSIBILITY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 201 PM CDT TUE JUN 23 2015
ECMWF SHOWS SOME CONVECTION DEVELOPING ACROSS THE EASTERN ZONES
THURSDAY EVENING. THIS MATCHES THE TAIL END OF THE 4 KM NAM.
WILL HAVE CHANCE POPS HERE AND SLIGHT POPS TO THE WEST. WIND AND
HAIL MAY BE POSSIBLE WITH THIS ACTIVITY AS THERE IS LOW END SHEAR
AND MODERATE CAPE. LOWS WILL BE MORE MILD FOR FAR WESTERN KANSAS
FRIDAY MORNING AS COOLER AIR ADVECTS IN. SPEAKING OF, HIGHS FRIDAY
WILL BE COOLER WITH 80S INSTEAD OF 90S POST FRONTAL. LOWS IN THE
60S ARE EXPECTED FOR SATURDAY MORNING. ANOTHER DAY WITH A BREAK IN
THE HEAT IS EXPECTED FOR SATURDAY WITH HIGHS IN THE 80S AGAIN. FOR
NEXT WEEK, THE WARM SECTOR WILL LIFT NORTHWARD WITH 90S RETURNING.
THE REALLY INTENSE HEAT LOOKS TO REMAIN WEST OF HERE AS THE RIDGE
AMPLIFIES OUT WEST AND NORTHERLY FLOW DEVELOPS ACROSS KANSAS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1201 AM CDT WED JUN 24 2015
VFR CONDITIONS ARE EXPECTED OVERNIGHT AS ONLY MID AND HIGH LEVEL
MOISTURE PRECEDES AN UPPER LEVEL TROUGH AS IT CROSSES WESTERN
KANSAS. AS THIS UPPER LEVEL DISTURBANCE PASSES SKIES WILL CLEAR
FROM WEST TO EAST EARLY THURSDAY MORNING. SOUTH TO SOUTHWEST WINDS
OVERNIGHT WILL BE AT 10 TO 15 KNOTS. RAP AND NAM WERE SIMILAR WITH
HAVING A 50 KNOT LOW LEVEL JET ACROSS SOUTHWEST KANSAS BETWEEN
06Z AND 12Z. THIS JET AXIS APPEARS TO BE LOCATED NEAR AND WEST OF
GCK AND HYS SO WILL INSERT AS WIND SHEAR GROUP INTO THESE TAFS
THROUGH 12Z THURSDAY. BY LATE MORNING THESE SOUTHERLY WINDS
INCREASE INTO THE 20 TO NEAR 25 KNOTS RANGE AS STRONGER WINDS
LOCATED IN THE 900MB TO 850MB LEVEL BEGIN TO MIX DOWN TO THE
SURFACE. THESE GUSTY WINDS WILL THEN CONTINUE THROUGH THE
REMAINDER OF THE AFTERNOON.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 71 96 68 87 / 0 10 10 20
GCK 71 95 66 87 / 10 10 10 20
EHA 69 95 66 88 / 0 10 10 20
LBL 70 97 68 88 / 0 10 10 30
HYS 73 92 66 85 / 10 10 10 20
P28 73 97 71 90 / 0 10 10 30
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...UMSCHEID
LONG TERM...99
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1041 PM MDT TUE JUN 23 2015
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 154 PM MDT TUE JUN 23 2015
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS RIDGE STILL IN
PLACE ACROSS SOUTHERN PLAINS WITH WESTERLY ZONAL FLOW ACROSS THE
NORTHERN PLAINS. WEAK SHORTWAVE TROUGHS AND MONSOONAL/PACIFIC FLOW
CONTINUE TO ROTATE ALONG THE WESTERN PERIPHERY OF THE RIDGE AND
INTO THE CENTRAL ROCKIES. AT THE SURFACE STATIONARY FRONT HAS
LIFTED TO NEAR SCOTT CITY JUST SOUTH OF OUR CWA WITH STATIONARY
FRONT ALONG FRONT RANGE.
THIS AFTERNOON-TONIGHT...GUIDANCE CONTINUES TO SHOW WARM FRONT
LIFTING NORTH THROUGH THE AFTERNOON AND EVENING AS LEE TROUGH
DEEPENS. THUNDERSTORMS HAVE ALREADY DEVELOPED ACROSS SOUTH CENTRAL
COLORADO. HIGH RES GUIDANCE CONTINUES TO SHOW CAP WEAKENING
ALONG THE FRONT FROM THE WEST TO THE EAST...AND THUNDERSTORMS
EITHER DEVELOPING OR MOVING INTO THE SW PART OF THE CWA SPREADING
NORTH AND EAST THIS EVENING. WHILE PWATS AND TD VALUES ARE
IMPRESSIVE...DEEP LAYER MIXING RATIOS/MOISTURE PROFILES ARE LESS
THAN FAVORABLE FOR WIDESPREAD COVERAGE LOCALLY WITHOUT
ORGANIZATION INTO MORE OF A CLUSTER FROM THE WEST. SHORTWAVE
TROUGH ADVERTISED TO MOVE ACROSS CWA THIS EVENING COULD HELP WITH
INITIATION...SO DESPITE THE DRY LAYERS ALOFT 20 TO 30 POPS STILL
SEEMS REASONABLE. VEERING SHEER PROFILES IN THE 0-3KM LAYER COULD
HELP SUPERCELL POTENTIAL ASSUMING THUNDERSTORMS DEVELOP THIS
AFTERNOON/EARLY EVENING ALONG WARM FRONT BEFORE LOW LEVELS
STABILIZE. AS EVENING PROGRESSES PROFILES FAVOR MAINLY ELEVATED
THUNDERSTORMS...AND GOOD EFFECTIVE SHEER VALUES SHOULD STILL
SUPPORT LARGE HAIL/DAMAGING WIND THREAT WITH ANY ONGOING ACTIVITY.
WEDNESDAY...WARM FRONT STALLS NEAR THE KS/NE BORDER EARLY WEDNESDAY
MORNING WITH MOISTURE POOLING NORTH OF THIS FRONT EARLY WEDNESDAY
MORNING WHEN FOG/STRATUS COULD DEVELOP. GUIDANCE STILL SHOWING A
POTENTIAL BUT I AM STILL NOT SURE VIS WILL BE LOW ENOUGH TO INCLUDE
MENTION IN FORECAST...SO WILL MONITOR SHORT RANGE
GUIDANCE/TRENDS. FRONT SETS UP ROUGHLY THROUGH THE CENTRAL PART OF
THE CWA AS SURFACE LOW SHIFTS EAST WEDNESDAY AFTERNOON...WITH NEAR
100F TEMPS SOUTH OF THIS FRONT AND IN THE 90S TO THE NW. THIS
FRONT WILL ACT AS A FOCUS FOR POSSIBLY THUNDERSTORM DEVELOPMENT IN
THE AFTERNOON...AGAIN AIDED BY HEIGHT FALLS FROM WEAK SHORTWAVE
ROTATING INTO THE REGION FROM THE WEST. I KEPT 20 POPS CONFINED TO
THE SW IN THE AFTERNOON...THOUGH DEPENDING ON CAP STRENGTH I COULD
SEE A ISOLATED THUNDERSTORM FURTHER EAST. NOT A STRONG SIGNAL IN
THE AFTERNOON FURTHER EAST..SO I FAVOR STICKING WITH A
CONSERVATIVE APPROACH FOR NOW.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 318 PM MDT TUE JUN 23 2015
FORECAST PROBLEMS WILL BE CHANCES OF THUNDERSTORMS THROUGH FRIDAY.
SATELLITE SHOWING A PROGRESSIVE/NEAR ZONAL FLOW FROM THE PACIFIC
INTO THE WESTERN ATLANTIC. BROAD UPPER RIDGE NOW IN PLACE OVER MOST
OF THE SOUTHERN HALF OF THE COUNTRY.
AT JET LEVEL...MODELS START OUT FINE. AT MID LEVELS...THE CANADIAN
AND GFS WERE DOING A LITTLE BETTER THAN THE NAM AND ECMWF. THE ECMWF
WAS DOING A LITTLE BETTER THAN THE SREF/GFS/NAM ON THE SURFACE WIND
AND PRESSURE FIELD. THE SREF/ECMWF/NAM WERE DOING A LITTLE BETTER
THAN THE REST OF THE OUTPUT ON THE LOW LEVEL THERMAL FIELD.
WEDNESDAY NIGHT...RIGHT REAR QUADRANT OF JET CONTINUES ACROSS THE
NORTHERN HALF OF THE AREA THROUGH THE NIGHT ALTHOUGH IT WEAKENS A
LITTLE LATER IN THE NIGHT. BY LATE IN THE AFTERNOON THE FRONT HAS
SAGGED DOWN THROUGH ABOUT THE WHOLE AREA EXCEPT MAYBE FOR THE
SOUTHERN FRINGE. MID LEVEL SHORTWAVE/LIFT MOVE AFFECT THE
NORTHWEST HALF OF THE AREA THROUGH MIDDLE OF THE NIGHT BEFORE
MOVING OUT OF THE NORTHERN PORTION DURING THE OVERNIGHT HOURS. SO
THE NORTHWEST HALF OF THE AREA WILL HAVE THE HIGHEST POPS
ESPECIALLY THE FAR WEST AND NORTH.
THURSDAY/THURSDAY NIGHT... SHORTWAVE TROUGHS IN NORTHWEST FLOW IS
ALWAYS A TRICKY AND POTENTIALLY ACTIVE SETUP FOR THE AREA. THERE
LOOKS TO BE SOME WEAK LIFT FROM THE RIGHT REAR QUADRANT DURING THE
AFTERNOON. MAIN JET LOOKS TO STAY NORTH OF THE AREA DURING THE
NIGHT. THE FRONT INITIALLY STAYS CLOSE TO THE SOUTHERN PORTION OF
THE AREA BEFORE MOVING EVEN FARTHER SOUTH.
MULTIPLE SHORTWAVE TROUGHS MAKE AFTERNOON AND NIGHTTIME
PRECIPITATION FORECAST MESSY. ONE SHORTWAVE WILL AFFECT THE
SOUTHEAST PORTION OF THE AREA DURING THE AFTERNOON AS ANOTHER WAVE
APPROACHES THE FAR WEST. ALSO POST FRONTAL UPSLOPE OR THE
PROXIMITY OF THE BOUNDARY TO THE WESTERN PORTION OF THE AREA WILL
HELP DEVELOP STORMS. SO AT THIS TIME WILL HAVE SLIGHT CHANCE TO
LOW CHANCE POPS ALONG THE SOUTHEAST AND WESTERN PORTIONS OF THE
AREA.
FOR THE NIGHT...A DECENT BAROCLINIC ZONE LOOKS TO MOVE ACROSS IN
ADVANCE OF A FEW SHORTWAVE TROUGHS. ONE SHORTWAVE TROUGH MOVES
ACROSS THE SOUTHWEST PORTION WITH ANOTHER MOVING ACROSS THE NORTHERN
PORTION. COMBINATION OF THE BAROCLINIC ZONE AND FAVORABLE THETA-E
LAPSE RATES SHOULD ALLOW FOR A GOOD RESPONSE TO THE LIFT. SO CHANCE
POPS WILL TRANSITION FROM NORTHWEST TO SOUTHEAST DURING THIS TIME.
SEE THE POTENTIAL FOR THE POPS TO BE RAISED FROM THIS.
AS STATED ABOVE MOST IF NOT ALL OF THE AREA WILL BE IN POST FRONTAL
UPSLOPE FLOW AND LINGERING CLOUD COVER. AS A RESULT THE HIGH
TEMPERATURES WILL BE COOLER. DEPENDING ON HOW LONG LOW LEVEL CLOUD
COVER LASTS...TEMPERATURES MAY NEED TO BE MADE EVEN COOLER THAN WHAT
IS IN THERE NOW.
FRIDAY...MAIN JET REMAINS NORTH OF THE AREA. DECENT BAROCLINIC ZONE
AND COLD AIR ADVECTION WILL CONTINUE TO MOVE ACROSS DURING THE DAY.
SHORTWAVES WILL ROTATE THROUGH THE NORTHERLY FLOW ALOFT WITH A
MODERATELY STRONG SHORTWAVE MOVING THROUGH FROM LATE IN THE
MORNING THROUGH MID AFTERNOON. SO HAVE SLIGHT TO CHANCE POPS FOR
NOW.
COLD AIR ALOFT...POST FRONTAL SURFACE WINDS...CLOUD COVER AND
PRECIPITATION WILL HELP KEEP TEMPERATURES FROM RISING TOO MUCH.
TEMPERATURES LOOK TO BE COOLER THAN THE PREVIOUS DAY BUT ONCE AGAIN
THE POTENTIAL IS THERE AGAIN TO HAVE TO MAKE THESE TEMPERATURES
COOLER.
FRIDAY NIGHT THROUGH TUESDAY...PATTERN WILL AMPLIFY THROUGH THE
PERIOD WITH A RATHER STRONG/SHARP UPPER RIDGE TO OUR WEST. MODELS
ARE IN GOOD AGREEMENT WITH THIS. PERIODIC SHORTWAVE TROUGHS ALONG
WITH THE ASSOCIATED SURFACE FEATURES WILL MOVE THROUGH IN THE
NORTHWEST TO EVENTUALLY NORTH FLOW ALOFT.
HARD TO RULE OUT PRECIPITATION IN THIS PERIOD. AT THIS TIME...IT
LOOKS LIKE ISOLATED AFTERNOON AND EVENING CONVECTION...MAINLY IN MY
WESTERN/NORTHERN PORTIONS THROUGH THE PERIOD. THE CRH_INIT DEPICTED
THIS SCENARIO NICELY AND DID NOT CHANGE THE POPS THAT I WAS GIVEN.
THE ONLY TRULY DRY PERIOD LOOKS TO BE MONDAY AND MONDAY NIGHT.
TEMPERATURES SHOULD NOT GET TOO HOT OR WAY ABOVE NORMAL DUE TO THE
NORTHERLY FLOW ALOFT AND PERSISTENT EASTERLY SURFACE WINDS OF SOME
SORT. THIS IS ALSO DEPICTED NICELY BY THE INIT AND DID NOT CHANGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1027 PM MDT TUE JUN 23 2015
CURRENT RADAR AND STORM TRENDS INDICATE INCREASING CHANCES THAT A
STORM WILL MOVE INTO KMCK NEAR THE BEGINNING OF THIS FORECAST. A
VICINITY THUNDERSTORM CANNOT BE RULED OUT NEAR KGLD AS WELL.
OVERNIGHT STORMS WILL WEAKEN AND DISSIPATE. FORECAST SOUNDINGS
INDICATE STRATUS AT KMCK TOWARD SUNRISE AND THEN BREAKING OUT
AROUND 15Z. CONDITIONS MAY GET CLOSE TO MVFR AT KMCK. DURING THE
DAY WEDNESDAY, EXPECT VFR CONDITIONS AT BOTH SITES WITH A SLIGHT
CHANCE OF THUNDERSTORMS NEAR KGLD DURING THE EVENING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...BULLER
AVIATION...FS
AREA FORECAST DISCUSSION
NWS JACKSON KY
935 PM EDT THU JUN 25 2015
.UPDATE...
ISSUED AT 935 PM EDT THU JUN 25 2015
SHOWERS AND STORMS CONTINUE ACROSS NORTHEASTERN KENTUCKY THIS
EVENING...WITH MOST OF THEM PRODUCING HEAVY RAINFALL AND FREQUENT
LIGHTNING. STORMS EARLIER THIS AFTERNOON PRODUCED UP TO QUARTER
SIZED HAIL...AND THIS REMAINS POSSIBLE TONIGHT AS WELL.
SOME PATCHY FOG/MIST HAS ALREADY SET IN AT JKL DUE TO THE
MULTIPLE ROUNDS OF RAIN THIS EVENING...SO HAVE ADDED IN PATCHY
VALLEY FOG TO THE NORTHERN HALF OF THE CWA. OTHERWISE...ONLY MINOR
ADJUSTMENTS WERE MADE TO THE T/TD GRIDS TO ALIGN THEM WITH OBS.
SENT UPDATED GRIDS TO NDFD AND WEB SERVERS.
UPDATE ISSUED AT 640 PM EDT THU JUN 25 2015
STRONG TO SEVERE STORMS HAVE FINALLY STARTED TO DEVELOP ACROSS
EASTERN KENTUCKY BUT REMAIN MOSTLY SCATTERED IN NATURE. EXPECT THE
COVERAGE TO INCREASE THROUGHOUT THE EVENING HOURS SINCE THE CAP IS
NOW BROKEN. DECIDED TO BUMP POPS UP TO INCLUDE AT LEAST A SLIGHT
CHANCE POP ACROSS OUR SOUTHERN COUNTIES...AS WELL AS ADJUST T/TD
GRIDS TO ALIGN THEM WITH RECENT OBS. SENT UPDATED GRIDS TO NDFD
AND WEB SERVERS.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 359 PM EDT THU JUN 25 2015
CURRENT CONDITIONS ACROSS THE AREA FEATURE A STATIONARY BOUNDARY
DRAPED ACROSS CENTRAL AND EASTERN KENTUCKY. CURRENT VISIBLE SHOT
ACROSS THE AREA SHOWS SOME BREAKS IN THE CLOUD COVER ACROSS THE
AREA. THIS HAS ALLOWED SOME INCREASED HEATING DESPITE THE CAP
AND LACK OF INSTABILITY FROM THIS MORNINGS MCS. IF THE BREAKS
AND INCREASED HEATING CONTINUES...SOME CONVECTION MAY BEGIN TO
DEVELOP IN THE NEXT COUPLE OF HOURS. THE ISSUE HERE IS IF THE CAP
AT 800MB IS BROKEN. THE HRRR HAS BEEN SLIGHTLY LESS STELLAR
HINTING AT CONVECTION ALL AFTERNOON BUT TO NO AVAIL. SOME SHOWER
ACTIVITY HAS DEVELOPED UPSTREAM IN SOUTHERN IN AND WESTERN KY SO
WILL INTRODUCE SOME POPS INTO EASTERN KENTUCKY AFTER 21Z THIS
AFTERNOON.
HEADING INTO TONIGHT...THE NEXT CLUSTER OF STORMS DEVELOPS AND
BEGINS TO TRACK SOUTHEAST INTO KY. THE FORMATION OF THIS AREA
SHOULD BEGIN IN CENTRAL KY OR EVEN A BIT FURTHER WEST. IT IS WORTH
MENTIONING THAT MODELS HAVE BEEN LESS THAN STELLAR PICKING OUT
THIS DEVELOPMENT. THOUGH WITH TRENDS AND COLLABORATION WITH
NEIGHBORING OFFICES...WILL BE INTRODUCING LIKELY POPS INTO EASTERN
KENTUCKY SHORTLY AFTER 00Z BUT DEVELOPMENT AND A STARTING POINT
FOR CONVECTIVE INITIATION IS A BIT OF A TOUGH CALL.
TOMORROW...A STRONGER WAVE DIPS SOUTH INTO THE LOWER OH VALLEY
CROSSING OVER THE RIDGE OUT WEST AND MAKES FOR AN INTERESTING
SITUATION FOR KY ON FRIDAY EVENING AND FRIDAY NIGHT. WITH
THIS...THE WARM FRONT WITH A STRONG SOUTHERLY SURGE PUSHES
NORTH THROUGH THE AREA. AHEAD OF THIS SHOULD BE STRONG CONVECTION
AND POSSIBLY SEVERE THUNDERSTORMS. EARLY MORNING CONVECTION MAY
HINDER THIS A BIT BUT THE WARM AND MOIST AIR SURGING FROM THE
SOUTH SHOULD MAKE FRIDAY EVENING AND INTO FRIDAY NIGHT QUITE
INTERESTING. WILL MENTION THIS PERIOD IN THE HWO AS THIS WILL
BEGIN AN ACTIVE PERIOD.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 359 PM EDT THU JUN 25 2015
MODELS APPEAR TO BE IN GOOD AGREEMENT WITH MID AND UPPER LEVEL FLOW
THROUGH THE EXTENDED. WE FIND OURSELVES UNDER THE INFLUENCE OF A
HIGH AMPLITUDE PATTERN WITH A MEAN EAST CONUS TROUGH AND WEST CONUS
RIDGE. AS SUCH WE CAN EXPECT BELOW NORMAL TEMPERATURES THROUGH THE
PERIOD AND IN GENERAL AN UNSETTLED WEATHER PATTERN.
MODEL GUIDANCE IS IN GOOD AGREEMENT WITH A POSITIVELY TILTED TROUGH
CUTTING OFF ACROSS THE GREAT LAKES REGION BY EARLY SATURDAY. THIS
FEATURE WILL EVENTUALLY TRACK EAST...BECOMING NEGATIVELY TILTED AS
IT MOVES INTO SOUTHERN NEW ENGLAND STATES SUNDAY. ADDITIONAL
SHORTWAVE ENERGY DIGS OUT A REINFORCING TROUGH OVER OUR REGION BY
MONDAY WHICH ONLY GRADUALLY LIFTS OUT TO THE NORTHEAST BY THE END OF
THE FORECAST WINDOW. BY THEN THERE IS A TENDENCY FOR THE PATTERN TO
BECOME LESS AMPLIFIED AND A BIT MORE ZONALLY ORIENTED AS WESTERN
CONUS RIDGE SHIFTS OUT INTO THE PACIFIC AND ADDITIONAL SHORTWAVE
ENERGY DROPS INTO THE UPPER MIDWEST.
AT THE SURFACE...THE INITIAL TROUGH/CUT OFF LOW WILL AID IN
DEVELOPING A SURFACE LOW ACROSS THE WESTERN OHIO VALLEY AT THE START
OF THE PERIOD. THIS RELATIVELY DEEP AND WELL ORGANIZED SFC LOW WILL
RIDE UP THE OHIO VALLEY OVER THE WEEKEND...WITH A TRAILING COLD
FRONT ADVANCING ACROSS OUR AREA SATURDAY MORNING. ANOTHER FRONTAL
SYSTEM WILL SWEEP THROUGH THE REGION AT THE START OF THE WEEK...LATE
MONDAY INTO TUESDAY. ONCE AGAIN...THIS PATTERN WILL ENSURE BELOW
NORMAL TEMPS THROUGH THE PERIOD WITH HIGHS IN THE MID 70S TO LOWER
80S AND LOWS MAINLY FALLING INTO THE 50S TO LOWER 60S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 804 PM EDT THU JUN 25 2015
SHOWERS AND THUNDERSTORMS HAVE DEVELOPED OVER THE PAST COUPLE OF
HOURS...MAINLY IN AND AROUND THE JKL...SJS...AND SME TAF SITES.
EXPECT THESE STORMS TO GRADUALLY WEAKEN WITH THE LOSS OF DAYTIME
HEATING. BUT ANTICIPATE CIGS/VIS TO LOWER OVERNIGHT TONIGHT DUE TO
LEFTOVER SHOWERS AND FOG DEVELOPMENT...WITH ALTERNATE MIN VIS
POSSIBLE AT THE SJS...SME AND LOZ TAF SITES AND MVFR VIS AT THE
JKL AND SYM TAF SITES. A LULL IN PRECIP DURING THE MORNING HOURS
WILL ALLOW FOR VFR CONDITIONS FOR A TIME ON FRIDAY...BEFORE
AFTERNOON THUNDERSTORM ACTIVITY DEVELOPS ONCE AGAIN. WINDS WILL
REMAIN GENERALLY LIGHT THROUGH THE PERIOD OUTSIDE OF STORMS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JVM
SHORT TERM...SHALLENBERGER
LONG TERM...RAY/DJ
AVIATION...JVM/HAL
AREA FORECAST DISCUSSION
NWS JACKSON KY
804 PM EDT THU JUN 25 2015
.UPDATE...
ISSUED AT 640 PM EDT THU JUN 25 2015
STRONG TO SEVERE STORMS HAVE FINALLY STARTED TO DEVELOP ACROSS
EASTERN KENTUCKY BUT REMAIN MOSTLY SCATTERED IN NATURE. EXPECT THE
COVERAGE TO INCREASE THROUGHOUT THE EVENING HOURS SINCE THE CAP IS
NOW BROKEN. DECIDED TO BUMP POPS UP TO INCLUDE AT LEAST A SLIGHT
CHANCE POP ACROSS OUR SOUTHERN COUNTIES...AS WELL AS ADJUST T/TD
GRIDS TO ALIGN THEM WITH RECENT OBS. SENT UPDATED GRIDS TO NDFD
AND WEB SERVERS.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 359 PM EDT THU JUN 25 2015
CURRENT CONDITIONS ACROSS THE AREA FEATURE A STATIONARY BOUNDARY
DRAPED ACROSS CENTRAL AND EASTERN KENTUCKY. CURRENT VISIBLE SHOT
ACROSS THE AREA SHOWS SOME BREAKS IN THE CLOUD COVER ACROSS THE
AREA. THIS HAS ALLOWED SOME INCREASED HEATING DESPITE THE CAP
AND LACK OF INSTABILITY FROM THIS MORNINGS MCS. IF THE BREAKS
AND INCREASED HEATING CONTINUES...SOME CONVECTION MAY BEGIN TO
DEVELOP IN THE NEXT COUPLE OF HOURS. THE ISSUE HERE IS IF THE CAP
AT 800MB IS BROKEN. THE HRRR HAS BEEN SLIGHTLY LESS STELLAR
HINTING AT CONVECTION ALL AFTERNOON BUT TO NO AVAIL. SOME SHOWER
ACTIVITY HAS DEVELOPED UPSTREAM IN SOUTHERN IN AND WESTERN KY SO
WILL INTRODUCE SOME POPS INTO EASTERN KENTUCKY AFTER 21Z THIS
AFTERNOON.
HEADING INTO TONIGHT...THE NEXT CLUSTER OF STORMS DEVELOPS AND
BEGINS TO TRACK SOUTHEAST INTO KY. THE FORMATION OF THIS AREA
SHOULD BEGIN IN CENTRAL KY OR EVEN A BIT FURTHER WEST. IT IS WORTH
MENTIONING THAT MODELS HAVE BEEN LESS THAN STELLAR PICKING OUT
THIS DEVELOPMENT. THOUGH WITH TRENDS AND COLLABORATION WITH
NEIGHBORING OFFICES...WILL BE INTRODUCING LIKELY POPS INTO EASTERN
KENTUCKY SHORTLY AFTER 00Z BUT DEVELOPMENT AND A STARTING POINT
FOR CONVECTIVE INITIATION IS A BIT OF A TOUGH CALL.
TOMORROW...A STRONGER WAVE DIPS SOUTH INTO THE LOWER OH VALLEY
CROSSING OVER THE RIDGE OUT WEST AND MAKES FOR AN INTERESTING
SITUATION FOR KY ON FRIDAY EVENING AND FRIDAY NIGHT. WITH
THIS...THE WARM FRONT WITH A STRONG SOUTHERLY SURGE PUSHES
NORTH THROUGH THE AREA. AHEAD OF THIS SHOULD BE STRONG CONVECTION
AND POSSIBLY SEVERE THUNDERSTORMS. EARLY MORNING CONVECTION MAY
HINDER THIS A BIT BUT THE WARM AND MOIST AIR SURGING FROM THE
SOUTH SHOULD MAKE FRIDAY EVENING AND INTO FRIDAY NIGHT QUITE
INTERESTING. WILL MENTION THIS PERIOD IN THE HWO AS THIS WILL
BEGIN AN ACTIVE PERIOD.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 359 PM EDT THU JUN 25 2015
MODELS APPEAR TO BE IN GOOD AGREEMENT WITH MID AND UPPER LEVEL FLOW
THROUGH THE EXTENDED. WE FIND OURSELVES UNDER THE INFLUENCE OF A
HIGH AMPLITUDE PATTERN WITH A MEAN EAST CONUS TROUGH AND WEST CONUS
RIDGE. AS SUCH WE CAN EXPECT BELOW NORMAL TEMPERATURES THROUGH THE
PERIOD AND IN GENERAL AN UNSETTLED WEATHER PATTERN.
MODEL GUIDANCE IS IN GOOD AGREEMENT WITH A POSITIVELY TILTED TROUGH
CUTTING OFF ACROSS THE GREAT LAKES REGION BY EARLY SATURDAY. THIS
FEATURE WILL EVENTUALLY TRACK EAST...BECOMING NEGATIVELY TILTED AS
IT MOVES INTO SOUTHERN NEW ENGLAND STATES SUNDAY. ADDITIONAL
SHORTWAVE ENERGY DIGS OUT A REINFORCING TROUGH OVER OUR REGION BY
MONDAY WHICH ONLY GRADUALLY LIFTS OUT TO THE NORTHEAST BY THE END OF
THE FORECAST WINDOW. BY THEN THERE IS A TENDENCY FOR THE PATTERN TO
BECOME LESS AMPLIFIED AND A BIT MORE ZONALLY ORIENTED AS WESTERN
CONUS RIDGE SHIFTS OUT INTO THE PACIFIC AND ADDITIONAL SHORTWAVE
ENERGY DROPS INTO THE UPPER MIDWEST.
AT THE SURFACE...THE INITIAL TROUGH/CUT OFF LOW WILL AID IN
DEVELOPING A SURFACE LOW ACROSS THE WESTERN OHIO VALLEY AT THE START
OF THE PERIOD. THIS RELATIVELY DEEP AND WELL ORGANIZED SFC LOW WILL
RIDE UP THE OHIO VALLEY OVER THE WEEKEND...WITH A TRAILING COLD
FRONT ADVANCING ACROSS OUR AREA SATURDAY MORNING. ANOTHER FRONTAL
SYSTEM WILL SWEEP THROUGH THE REGION AT THE START OF THE WEEK...LATE
MONDAY INTO TUESDAY. ONCE AGAIN...THIS PATTERN WILL ENSURE BELOW
NORMAL TEMPS THROUGH THE PERIOD WITH HIGHS IN THE MID 70S TO LOWER
80S AND LOWS MAINLY FALLING INTO THE 50S TO LOWER 60S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 804 PM EDT THU JUN 25 2015
SHOWERS AND THUNDERSTORMS HAVE DEVELOPED OVER THE PAST COUPLE OF
HOURS...MAINLY IN AND AROUND THE JKL...SJS...AND SME TAF SITES.
EXPECT THESE STORMS TO GRADUALLY WEAKEN WITH THE LOSS OF DAYTIME
HEATING. BUT ANTICIPATE CIGS/VIS TO LOWER OVERNIGHT TONIGHT DUE TO
LEFTOVER SHOWERS AND FOG DEVELOPMENT...WITH ALTERNATE MIN VIS
POSSIBLE AT THE SJS...SME AND LOZ TAF SITES AND MVFR VIS AT THE
JKL AND SYM TAF SITES. A LULL IN PRECIP DURING THE MORNING HOURS
WILL ALLOW FOR VFR CONDITIONS FOR A TIME ON FRIDAY...BEFORE
AFTERNOON THUNDERSTORM ACTIVITY DEVELOPS ONCE AGAIN. WINDS WILL
REMAIN GENERALLY LIGHT THROUGH THE PERIOD OUTSIDE OF STORMS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JVM
SHORT TERM...SHALLENBERGER
LONG TERM...RAY/DJ
AVIATION...JVM/HAL
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
927 PM CDT THU JUN 25 2015
.DISCUSSION...
OUTFLOW BOUNDARY HAS PUSHED INTO NORTHEAST TEXAS LATE THIS EVENING
BUT CONVECTION HAS NOT BEEN ABLE TO SUSTAIN ITSELF THIS EVENING
LIKE THE PREVIOUS TWO EVENINGS. LATEST HRRR IN GOOD AGREEMENT WITH
THIS ASSESSMENT SO IT SHOULD BE SAFE TO REMOVE POPS FROM THE
FORECAST FOR THE REMAINDER OF THE EVENING. CONCERNING TEMPS...
HAVE LOWERED TEMPS A FEW DEGREES ACROSS N LA WHERE EARLIER
RAINFALL ALREADY HAD 02Z TEMPS NEAR OR AT FCST MIN TEMPS. DID
RAISE TEMPS A DEGREE OR TWO ACROSS NE TX WHERE THE RAINFALL DID
NOT MAKE IT...FOLLOWING PERSISTENCE OVER THE LAST SEVERAL MORNINGS
IN THIS LOCATION. WE ARE LEFT WITH AN EXPANSIVE CLOUD DEBRIS
PATTERN ON IR IMAGERY IN THE WAKE OF THE CONVECTION SO BEEFED UP
SKY CONDITIONS FOR THE NEXT 6 HOURS OR SO BUT THE CLOUD COVER
SHOULD BEGIN TO THIN AFTER MIDNIGHT.
OTHER DEWPOINT/WIND GRIDS CHANGES WERE MOSTLY COSMETIC. UPDATE OUT
SHORTLY...13.
&&
.PREV DISCUSSION... /ISSUED 707 PM CDT THU JUN 25 2015/
AVIATION...
SCT SHWRS/TSTM STILL ROAMING WESTWARD ON OUTFLOW FROM KSHV
VCNTY...DOWN INTO TOLEDO BEND COUNTRY FOR ANOTHER HOUR OR TWO. SFC
WINDS LIGHT S AND CLIMB WINDS SE-SW 10-20KTS...VEERING TO NW FLOW
BY 12KFT. SKC OVERNIGHT WITH MAYBE A SITE OR TWO WITH DAYBREAK BR.
ANOTHER ROUND OF DIURNAL HEATING CONVECTION FOR FRI. W/ A TWIST AS
A COLD FRONT EDGES INTO PLAY FOR THE OVERNIGHT AND MUCH OF SAT.
SCT/NUMEROUS STORMS EXPECTED...SOME NOCTURNAL. GUSTY WINDS AND
TURBULENCE NEAR DOWNPOURS/TOWERS WITH BETTER WX BY SUN.
24
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 75 93 75 85 / 10 20 60 60
MLU 74 93 75 86 / 10 30 60 60
DEQ 72 92 70 86 / 10 40 60 30
TXK 75 93 72 86 / 10 30 60 40
ELD 73 94 73 84 / 10 40 60 50
TYR 75 92 75 88 / 10 20 50 50
GGG 76 93 75 86 / 10 20 50 50
LFK 76 93 75 89 / 10 30 40 60
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
24/13
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
410 PM CDT WED JUN 24 2015
.SYNOPSIS...MOISTURE CONTINUES TO DEEPEN IN RESPONSE TO AN UPPER
LOW OVER THE SOUTHWESTERN GULF AND A PERSISTENT RIDGE OF HIGH
PRESSURE IN THE LOWER LEVELS OVER THE EASTERN GULF. THIS WILL GIVE
THE AREA A DECENT CHANCE FOR SHOWERS AND THUNDERSTORMS MAINLY
DURING THE AFTERNOON AND EVENING ON THURSDAY.
&&
.SHORT RANGE...THE HRRR DEPICTS ANOTHER IMPULSE MOVING THROUGH THE
ATCHAFALAYA IN EASTERLY FLOW AND MOVING INTO THE ACADIANA AREA
THIS EVENING BRINGING SCATTERED SHOWERS AND THUNDERSTORMS. WENT
HIGHER THAN GUIDANCE ON POPS DUE TO THIS FEATURE AS WELL AS HIGH
THETA AIR AND AMPLE MOISTURE WITH PRECIP WATER VALUES CONTINUING
ABOUT A STANDARD DEVIATION ABOVE CLIMO.
&&
.LONG RANGE...MODELS ARE STILL CONSISTENT ON A DIGGING UPPER LEVEL
TROF INTO THE MIDWEST WITH A FAIRLY DEEP LOW FOR THIS TIME OF YEAR
SOUTH OF THE GREAT LAKES. THIS WILL DRIVE A WEAK COLD FRONT INTO
OUR AREA AND BRING A LIKELY CHANCE FOR SHOWERS AND TSTMS THIS
WEEKEND. THE UPPER TROF REMAINS A FEATURE INTO NEXT WEEK OVER THE
EASTERN PORTION OF THE U.S. WHICH WILL WEAKEN THE RIDGE OVER OUR
AREA AND ALLOW FOR HIGHER THAN NORMAL RAIN CHANCES NEXT WEEK.
SWEENEY
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 73 91 77 90 / 30 40 20 30
LCH 75 90 79 88 / 30 40 10 30
LFT 77 92 77 88 / 30 40 10 30
BPT 76 90 78 89 / 30 30 10 30
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
PUBLIC...11
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
831 AM CDT WED JUN 24 2015
...SOUNDING DISCUSSION...
THE SOUNDING THIS MORNING DEPICTS AN ATMOSPHERE THAT IS MOIST AND
UNSTABLE. PW IS ABOVE AVERAGE AT 1.96 INCHES AND MIXED LAYER CAPE
IS 1000 J/KG... MOST UNSTABLE CAPE IS 2700 J/KG. A SHALLOW
TEMPERATURE INVERSION IS AT THE SFC TO 1500 FT AND WILL MIX OUT
QUICKLY. WINDS ARE LIGHT AND NORTHEASTERLY FROM THE SFC TO 500 MB
THEN BECOME EASTERLY THROUGH THE REST OF THE PROFILE. CONVECTIVE
TEMPERATURE ON THE SOUNDING IS LISTED AT 93F AND STORMS ARE
EXPECTED TO FIRE WITH DAYTIME HEATING SIMILAR TO THE PAST FEW
DAYS.
KRAUTMANN
&&
.PREV DISCUSSION... /ISSUED 333 AM CDT WED JUN 24 2015/
SHORT TERM...
CURRENTLY MONITORING TRENDS AND EVOLUTION OF CONVECTION OVER
ALABAMA AND NORTHERN MISSISSIPPI THIS MORNING AS A RESULT OF A
LARGE OUTFLOW BOUNDARY THAT IS MOWING SOUTHWEST THROUGH AN
UNSTABLE AIR MASS. THE SOUTHERN ALABAMA ACTIVITY HAS CONGEALED
INTO A RATHER LARGE AND EXPANDING MCS WITH PLENTY OF IN-CLOUD
LIGHTNING AND ONLY ABOUT 10 PERCENT CLOUD-TO-GROUND PRODUCTION.
THE LARGER SCALE MODELS ARE NOT HANDLING THIS DEVELOPMENT
PARTICULARLY WELLL BUT THE HIGHER RESOLUTION SHORT-RANGE
CONVECTIVE BASED MODELS LIKE THE HRRR AND WRF ARE LATCHED IN ON
CURRENT TRENDS. AS A RESULT...HAVE OPTED TO INCREASE RAIN CHANCES
TO 50 PERCENT WITH EARLY ONSET ON THE MISSISIPPI COAST...AND
EARLIER THAN TYPICAL IN LOUISIANA BY MID-MORNING. HIGH CAPE AND
LOW SHEAR ENVIRONMENT WOULD SUGGEST MAIN THREAT TO BE WET
MICROBURSTS OVER LAND AREAS AFTER SUNRISE AND TYPE II WATERSPOUT
PRODUCTION IN THE COASTAL WATERS AND POSSIBLY OVER AREA BAYS AND
INLAND WATERWAYS. RAINFALL CAN ALSO BE EFFICIENT WITH SOME
LOCALIZED PONDING POSSIBLE...THOUGH MUCH OF THE RAINFALL WILL BE
ANVIL DECAY TYPE AWAY FROM THE PRIMARY CORES. MOVEMENT AND
PROPAGATION DUE TO OUTFLOW SHOULD BE ABLE TO KEEP STORM TOTAL
RAINFALL AT MANAGEABLE LEVELS TODAY. CONVECTION WILL ALSO LIKELY
DISRUPT THE SEA BREEZE CYCLE TODAY...OR AT LEAST GREATLY DELAY THE
ONSET UNTIL MUCH LATER IN THE AFTERNOON AS THE AIR MASS WILL NEED
TIME TO RECOVER AFTER MORNING CONVECTION AND INDUCTION OF DEEPER
NORTHERLY FLOW ALOFT. OTHERWISE...TEMPERATURES OF MODEL CONSENSUS
WILL BE PROVIDED BUT MAY BE IN LINE FOR SOME BUSTS OR AT LEAST
ATYPICAL DIURNAL TREND BEHAVIORS DUE TO CLOUD COVER EARLY ON.
FRIDAY COULD BE A REPEAT AS A COLD POOL REMAINS IN PLACE ALOFT AND
NOCTURNAL CONVECTION MAY ONCE AGAIN ERUPT DUE TO OUTFLOW FEATURES
GENERATED FROM CONVECTION ALONG THE FRINGES OF UPPER RIDGE FARTHER
NORTH.
LONG TERM...
MODELS ARE STILL IN VERY GOOD AGREEMENT WITH LARGE SCALE TROUGHING
TO TAKE PLACE OVER THE WEEKEND. THIS SHOULD ALLOW A SURFACE
FRONTAL FEATURE TO SETTLE INTO THE AREA...POSSIBLY DROPPING INTO
THE NORTH GULF LATE SUNDAY...AND PROVIDING A GENERALLY COOLING TO
AT LEAST NEAR NORMAL TEMPERATURES FOR NEXT WEEK. THE PATTERN WOULD
ALSO FAVOR INCREASED CHANCES AT RAINFALL EACH DAY POSSIBLY IN MCS
FASHION IN BASE OF TROUGH BY MID-WEEK. CONSENSUS MODEL GUIDANCE ON
TEMPERATURES AND POPS DURING THE EXTENDED PORTION. 24/RR
AVIATION...
EXPECT VFR CONDITIONS TO PREVAIL THROUGH THE TAF PERIOD WITH
GENERALLY LIGHT AND VARIABLE WINDS. HOWEVER OVERNIGHT CONVECTION
FROM SOUTH CENTRAL ALABAMA CONTINUES TO DRIFT TOWARDS THE FORECAST
AREA THIS MORNING AND WILL PROBABLY HAVE TO AMEND TAFS BEFORE THE
12Z ISSUANCE TO ADD THUNDERSTORMS INTO THE KGPT TAF AND TO START
CONVECTION EARLIER AT KMCB AND KASD. WILL HAVE TO CONTINUE TO WATCH.
GUSTY WINDS AND FREQUENT LIGHTNING WILL BE THE MAIN THREATS. VSBY
WITHIN THUNDERSTORMS COULD DROP TO IFR CONDITIONS BUT OUTSIDE
OF CONVECTION EXPECT MOSTLY VFR CONDITIONS. 13/MH
MARINE...
A WEAK SURFACE RIDGE REMAINS ACROSS THE REGION WITH NO
MAJOR CHANGES TO THE FORECAST AS WINDS WILL BE GENERALLY 10 KNOTS OR
LESS. ISOLATED TO SCATTERED CONVECTION IS POSSIBLE EACH AFTERNOON.
THE PATTERN SHOULD BE BROKEN BY AN APPROACHING COLD FRONT ON
SATURDAY AS WIND SPEEDS AND SEAS WILL BEGIN TO PICK UP. 13/MH
DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...RIVER FLOOD WARNINGS ON MISSISSIPPI RIVER.
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 RISK SVR AND/OR DIRECT
TROPICAL THREATS; EVENTS OF NATIONAL SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 94 74 91 74 / 50 30 40 20
BTR 95 76 92 75 / 50 30 40 10
ASD 94 77 91 77 / 50 20 40 20
MSY 94 78 91 77 / 50 20 40 20
GPT 93 79 91 78 / 50 30 40 20
PQL 93 77 91 78 / 50 30 30 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
333 AM CDT WED JUN 24 2015
.SHORT TERM...
CURRENTLY MONITORING TRENDS AND EVOLUTION OF CONVECTION OVER
ALABAMA AND NORTHERN MISSISSIPPI THIS MORNING AS A RESULT OF A
LARGE OUTFLOW BOUNDARY THAT IS MOWING SOUTHWEST THROUGH AN
UNSTABLE AIR MASS. THE SOUTHERN ALABAMA ACTIVITY HAS CONGEALED
INTO A RATHER LARGE AND EXPANDING MCS WITH PLENTY OF IN-CLOUD
LIGHTNING AND ONLY ABOUT 10 PERCENT CLOUD-TO-GROUND PRODUCTION.
THE LARGER SCALE MODELS ARE NOT HANDLING THIS DEVELOPMENT
PARTICULARLY WELLL BUT THE HIGHER RESOLUTION SHORT-RANGE
CONVECTIVE BASED MODELS LIKE THE HRRR AND WRF ARE LATCHED IN ON
CURRENT TRENDS. AS A RESULT...HAVE OPTED TO INCREASE RAIN CHANCES
TO 50 PERCENT WITH EARLY ONSET ON THE MISSISIPPI COAST...AND
EARLIER THAN TYPICAL IN LOUISIANA BY MID-MORNING. HIGH CAPE AND
LOW SHEAR ENVIRONMENT WOULD SUGGEST MAIN THREAT TO BE WET
MICROBURSTS OVER LAND AREAS AFTER SUNRISE AND TYPE II WATERSPOUT
PRODUCTION IN THE COASTAL WATERS AND POSSIBLY OVER AREA BAYS AND
INLAND WATERWAYS. RAINFALL CAN ALSO BE EFFICIENT WITH SOME
LOCALIZED PONDING POSSIBLE...THOUGH MUCH OF THE RAINFALL WILL BE
ANVIL DECAY TYPE AWAY FROM THE PRIMARY CORES. MOVEMENT AND
PROPAGATION DUE TO OUTFLOW SHOULD BE ABLE TO KEEP STORM TOTAL
RAINFALL AT MANAGEABLE LEVELS TODAY. CONVECTION WILL ALSO LIKELY
DISRUPT THE SEA BREEZE CYCLE TODAY...OR AT LEAST GREATLY DELAY THE
ONSET UNTIL MUCH LATER IN THE AFTERNOON AS THE AIR MASS WILL NEED
TIME TO RECOVER AFTER MORNING CONVECTION AND INDUCTION OF DEEPER
NORTHERLY FLOW ALOFT. OTHERWISE...TEMPERATURES OF MODEL CONSENSUS
WILL BE PROVIDED BUT MAY BE IN LINE FOR SOME BUSTS OR AT LEAST
ATYPICAL DIURNAL TREND BEHAVIORS DUE TO CLOUD COVER EARLY ON.
FRIDAY COULD BE A REPEAT AS A COLD POOL REMAINS IN PLACE ALOFT AND
NOCTURNAL CONVECTION MAY ONCE AGAIN ERUPT DUE TO OUTFLOW FEATURES
GENERATED FROM CONVECTION ALONG THE FRINGES OF UPPER RIDGE FARTHER
NORTH.
.LONG TERM...
MODELS ARE STILL IN VERY GOOD AGREEMENT WITH LARGE SCALE TROUGHING
TO TAKE PLACE OVER THE WEEKEND. THIS SHOULD ALLOW A SURFACE
FRONTAL FEATURE TO SETTLE INTO THE AREA...POSSIBLY DROPPING INTO
THE NORTH GULF LATE SUNDAY...AND PROVIDING A GENERALLY COOLING TO
AT LEAST NEAR NORMAL TEMPERATURES FOR NEXT WEEK. THE PATTERN WOULD
ALSO FAVOR INCREASED CHANCES AT RAINFALL EACH DAY POSSIBLY IN MCS
FASHION IN BASE OF TROUGH BY MID-WEEK. CONSENSUS MODEL GUIDANCE ON
TEMPERATURES AND POPS DURING THE EXTENDED PORTION. 24/RR
&&
.AVIATION...
EXPECT VFR CONDITIONS TO PREVAIL THROUGH THE TAF PERIOD WITH
GENERALLY LIGHT AND VARIABLE WINDS. HOWEVER OVERNIGHT CONVECTION
FROM SOUTH CENTRAL ALABAMA CONTINUES TO DRIFT TOWARDS THE FORECAST
AREA THIS MORNING AND WILL PROBABLY HAVE TO AMEND TAFS BEFORE THE
12Z ISSUANCE TO ADD THUNDERSTORMS INTO THE KGPT TAF AND TO START
CONVECTION EARLIER AT KMCB AND KASD. WILL HAVE TO CONTINUE TO WATCH.
GUSTY WINDS AND FREQUENT LIGHTNING WILL BE THE MAIN THREATS. VSBY
WITHIN THUNDERSTORMS COULD DROP TO IFR CONDITIONS BUT OUTSIDE
OF CONVECTION EXPECT MOSTLY VFR CONDITIONS. 13/MH
&&
.MARINE...
A WEAK SURFACE RIDGE REMAINS ACROSS THE REGION WITH NO
MAJOR CHANGES TO THE FORECAST AS WINDS WILL BE GENERALLY 10 KNOTS OR
LESS. ISOLATED TO SCATTERED CONVECTION IS POSSIBLE EACH AFTERNOON.
THE PATTERN SHOULD BE BROKEN BY AN APPROACHING COLD FRONT ON
SATURDAY AS WIND SPEEDS AND SEAS WILL BEGIN TO PICK UP. 13/MH
&&
.DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...RIVER FLOOD WARNINGS ON MISSISSIPPI RIVER.
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 RISK SVR AND/OR DIRECT
TROPICAL THREATS; EVENTS OF NATIONAL SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 94 74 91 74 / 50 30 40 20
BTR 95 76 92 75 / 50 30 40 10
ASD 94 77 91 77 / 50 20 40 20
MSY 94 78 91 77 / 50 20 40 20
GPT 93 79 91 78 / 50 30 40 20
PQL 93 77 91 78 / 50 30 30 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
24/RR
13/MH
AREA FORECAST DISCUSSION
NWS GAYLORD MI
905 PM EDT THU JUN 25 2015
.UPDATE...
ISSUED AT 905 PM EDT THU JUN 25 2015
BROAD HIGH PRESSURE REMAINS DRAPED ACROSS THE NRN GREAT LAKES
REGION WITH GENERALLY LIGHT EASTERLY FLOW ACROSS NRN MICHIGAN
ALTHOUGH LAKE BREEZES AND OUTFLOW BOUNDARIES HAVE DOMINATING THE
SCENE TODAY. SATELLITE/WATER VAPOR IMAGERY CLEARLY SHOWS A SHORT
WAVE SAGGING DOWN INTO NRN MICHIGAN AND A DEFINITIVE PUSH OF SOME
DRIER AIR HEADING DOWN INTO NRN MICHIGAN BEHIND THE WAVE.
WITH THE LIGHT FLOW/HEATING AND SOME INSTABILITY/WEAK QG-
FORCING...WE GOT OUR INLAND CONVECTION TODAY...SOME OF WHICH
CONTINUES TO PERCOLATE AT THIS HOUR.
REST OF TONIGHT...ONGOING INLAND CONVECTION WILL CONTINUE TO
PERCOLATE ABOUT FOR A FEW MORE HOURS UNTIL REMAINING INSTABILITY
FADES. HAVE STRETCHED INLAND POPS INTO THE OVERNIGHT HOURS TO
COVER IT...ALTHOUGH I/VE SEEN THIS SORT OF STUFF LAST WELL INTO
THE NIGHT. OTHERWISE...DRIER AIR WILL EVENTUALLY SAG DOWN THROUGH
NRN LOWER MICHIGAN SUPPRESSING MUCH OF THIS MID AND HIGH CLOUD
COVER INTO THE LOWER LAKES DURING THE OVERNIGHT LEADING TO
DECREASING CLOUD TREND FOR ALL AREAS. SOME FOG IS POSSIBLE
PARTICULARLY FOR AREAS THAT HAVE HAD RAIN IN THE LAST FEW HOURS.
&&
.NEAR TERM...(THIS EVENING THROUGH TONIGHT)
ISSUED AT 309 PM EDT THU JUN 25 2015
THE STORM SYSTEM WHICH MOVED INTO THE OHIO VALLEY AND SRN GREAT
LAKES EARLIER...WILL PUSH EAST TOWARD THE MID ATLANTIC TONIGHT WHILE
A LARGE AREA OF HIGH PRESSURE BEGINS TO SETTLE INTO THE NORTHERN
GREAT LAKES. AT UPPER LVLS...A 500MB TROUGH CURRENTLY DROPPING
SOUTHWARD ACROSS THE STATE...WILL WEAKEN AND MOVE EAST OF THE REGION
AFTER 06Z. THE OVERALL TREND OVERNIGHT INTO EARLY FRIDAY WILL BE
CLEARING SKIES WITH DIMINISHING PCPN.
MODEL SOUNDINGS AND MSTR PROGS SHOWING SUFFICIENT MSTR IN PLACE
ACRS THE GREAT LAKES TO CONTINUE PCPN THROUGH THE EVENING HOURS.
850MB DEW PTS WILL BE BETWEEN 9C AND 11C...SFC DEW PTS WILL LINGER
IN THE MID AND UPPER 50S WHILE MODEL SOUNDINGS SHOW PWAT VALUES
NEAR 1.20 INCHES. FORCING THIS EVENING WILL BE FROM A COMBINED
EFFORT OF LAKE BREEZE BOUNDARIES AND UPPER LVL CONVERGENCE.
500-300MB QVECTORS SHOW FORCING (ASSOCIATED WITH THE 500MB
TROUGH)...CENTERED OVER NORTHERN MICHIGAN THIS EVENING BEFORE
SHIFTING EAST BY 06Z. CURRENT SFC OBS SHOWING SOME LAKE BREEZE
DEVELOPMENT THIS AFTN IN WEAK SYNOPTIC WIND FLOW AND AFTN TEMPS IN
THE MID 70S. THE LAKE BREEZE FORMATION HAS HELPED CONCENTRATE MOST
OF THE PCPN THIS AFTN TO INTERIOR PORTIONS OF NRN LWR MI. A
THUNDERSTORM IS ALSO POSSIBLE THIS EVENING...AS MODEL SOUNDINGS
AND HRRR DATA SHOW CAPE VALUES NEARING 1200 J/KG (AWAY FROM THE
GREAT LAKES). CAPES VALUES DIMINISH QUICKLY TO UNDER 500 J/KG ARND
03Z...AS DRIER AIR BEGINS TO FILTER INTO NRN MI. MODEL SOUNDINGS
AND MSTR PROGS SHOW MUCH DRIER AIRMASS TO DEVELOP OVER THE NRN
GREAT LAKES AFTER 03Z...THE RESULT OF A LARGE AREA OF CANADIAN
HIGH PRESSURE SETTLING FURTHER SOUTH INTO MI. 850/500MB RH FALLS
FROM 80 PCT TO UNDER 40 PCT...PWAT VALUES FALL FROM 1.20IN TO
0.50IN AND 850MB DEW PTS DRY FROM ARND 12C TO ARND 4C.
OVERALL WILL CONTINUE CURRENT FORECAST TREND OF SCATTERED SHOWERS
AND A FEW THUNDERSTORMS THIS EVENING...ENDING AROUND MIDNIGHT FOR
MOST LOCATIONS. WILL MENTION SOME PATCHY FOG OVERNIGHT AS TEMPS FALL
THROUGH THE 50S WHILE SFC DEW PTS SLOWLY DROP INTO THE LOWER 50S.
&&
.SHORT TERM...(FRIDAY THROUGH SUNDAY)
ISSUED AT 309 PM EDT THU JUN 25 2015
ZONAL FLOW BECOMING MORE AMPLIFIED OVER THE NEXT SEVERAL DAYS AS
QUASI-PERMANENT WESTERN CONUS RIDGE BUILDS WITH DOWNSTREAM
TROUGHING ACROSS THE EASTERN STATES. ALTHOUGH AIRMASS IS BECOMING
DRIER ON FRIDAY...STILL A HINT OF SOME HIGHER LOW LEVEL
MOISTURE/H9-H8 THETA-E RIDGING UP THE US-131 AND I-75 CORRIDORS IN
NORTHERN LOWER AND OVER PARTS OF EASTERN UPPER. THIS MOISTURE
COMBINED WITH SOME LAKE BREEZE CONVERGENCE...CAN/T RULE OUT AN
ISOLATED AFTERNOON SHOWER AND WILL ADD THIS TO THE FORECAST.
OTHERWISE...A TERRIFIC STRETCH OF SUMMER WEATHER FOR THE WEEKEND.
WILL STILL HAVE TO KEEP AN EYE ON THE UPPER LOW CLOSING OFF OVER
THE NORTHERN OHIO VALLEY ON SATURDAY AND PUSHING NORTH/NORTHEAST
INTO THE WESTERN LAKES. MODEL CONSENSUS STILL KEEPS THIS SYSTEM
JUST SOUTH/EAST OF OUR AREA...WHICH SEEMS PLAUSIBLE GIVEN THE LACK
OF DOWNSTREAM BLOCKING. BUT IT WILL BE VERY CLOSE FOR AREAS NEAR
SAGINAW BAY AND SOMETHING THAT COULD RESULT IN A FEW SHOWERS
CREEPING NORTHWARD TOWARD GLADWIN/ARENAC/IOSCO COUNTIES LATER
SATURDAY INTO SATURDAY NIGHT. NORTHERN MICHIGAN WILL BE BETWEEN
SYSTEMS ON SUNDAY...WITH UPPER LOW TO THE EAST AND NEXT UPSTREAM
SHORTWAVE DIVING THROUGH THE UPPER MIDWEST. THE END RESULT SHOULD
BE A FAIRLY NICE DAY WITH POSSIBLY A FEW MORE CLOUDS BUT
COMFORTABLE TEMPERATURES/DRY CONDITIONS.
&&
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 309 PM EDT THU JUN 25 2015
RIDGING OVER THE WESTERN THIRD OF THE CONUS WILL LEAD TO TROUGHING
OVER THE EASTERN TWO-THIRDS THROUGH MUCH...IF NOT ALL OF THE
EXTENDED PERIOD. THIS WILL LEAD TO SLIGHTLY COOLER THAN NORMAL
TEMPERATURES AND INCREASED CHANCES FOR SCATTERED RAIN SHOWERS AND
PERHAPS A FEW THUNDERSTORMS FROM SUNDAY NIGHT THROUGH AT LEAST
TUESDAY NIGHT (ALTHOUGH RECENT TRENDS HAVE INDICATED LIMITED
MOISTURE ACROSS NORTHERN MICHIGAN THROUGH THE MONDAY-TUESDAY
TIMEFRAME...SO BY ALL MEANS NEITHER DAY LOOKS LIKE A WASHOUT).
TOWARD THE VERY END OF THE PERIOD...LONG-RANGE GLOBAL MODEL GUIDANCE
SUGGESTS A MORE MOISTURE-RICH SYSTEM TO APPROACH THE MIDWEST/GREAT
LAKES...PERHAPS PROVIDING A BETTER CHANCE AT WIDESPREAD RAIN ACROSS
THE REGION. LOTS OF TIME TO IRON OF THE DETAILS ON IF/WHEN THAT`S
EXPECTED TO OCCUR.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 731 PM EDT THU JUN 25 2015
VFR CONDITIONS PERSIST ACROSS NRN LOWER MICHIGAN ALTHOUGH BKN-OVC MID
CLOUD WILL LINGER THROUGH THE EVENING HOURS BEFORE THINNING OUT
OVERNIGHT. SPOTTY HEATING OF THE DAY SHOWERS ARE OUT THERE AS WELL
BUT LARGELY IMPACTING INTERIOR NRN LOWER MICHIGAN. AS CLOUD COVER
THINS LATER TONIGHT...THERE IS A RISK FOR SOME FOG DEVELOPMENT
PARTICULARLY AT PLN AND APN...WITH MVFR CONDITIONS AND RISK FOR
IFR VSBYS OVERNIGHT.
WINDS GO NEARLY CALM BY LATER THIS EVENING...INCREASE AGAIN ON
FRIDAY BUT REMAIN UNDER 10 KNOTS FOR THE MOST PART. LAKE BREEZE
WIND DIRECTIONS WILL AGAIN DOMINATE THE TERMINAL SITES BY
AFTERNOON.
&&
.MARINE...
ISSUED AT 309 PM EDT THU JUN 25 2015
WINDS AND WAVES ARE TO REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA
THROUGH THE FORECAST PERIOD...AS A LARGE AREA OF CANADIAN HIGH
PRESSURE SINKS SOUTH OVER THE GREAT LAKES. MAINLY DRY CONDS CAN BE
EXPECTED IN THE NEARSHORE AREAS THROUGH THE FORECAST PERIOD. HOWEVER
SCATTERED SHOWERS AND A FEW THUNDERSTORMS WILL CONTINUE THIS EVENING
AS AN UPPER TROUGH EXITS THE STATE.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...ADAM
NEAR TERM...SWR
SHORT TERM...KEYSOR
LONG TERM...GILLEN
AVIATION...ADAM
MARINE...SWR
AREA FORECAST DISCUSSION
NWS GAYLORD MI
731 PM EDT THU JUN 25 2015
.NEAR TERM...(THIS EVENING THROUGH TONIGHT)
ISSUED AT 309 PM EDT THU JUN 25 2015
THE STORM SYSTEM WHICH MOVED INTO THE OHIO VALLEY AND SRN GREAT
LAKES EARLIER...WILL PUSH EAST TOWARD THE MID ATLANTIC TONIGHT WHILE
A LARGE AREA OF HIGH PRESSURE BEGINS TO SETTLE INTO THE NORTHERN
GREAT LAKES. AT UPPER LVLS...A 500MB TROUGH CURRENTLY DROPPING
SOUTHWARD ACROSS THE STATE...WILL WEAKEN AND MOVE EAST OF THE REGION
AFTER 06Z. THE OVERALL TREND OVERNIGHT INTO EARLY FRIDAY WILL BE
CLEARING SKIES WITH DIMINISHING PCPN.
MODEL SOUNDINGS AND MSTR PROGS SHOWING SUFFICIENT MSTR IN PLACE
ACRS THE GREAT LAKES TO CONTINUE PCPN THROUGH THE EVENING HOURS.
850MB DEW PTS WILL BE BETWEEN 9C AND 11C...SFC DEW PTS WILL LINGER
IN THE MID AND UPPER 50S WHILE MODEL SOUNDINGS SHOW PWAT VALUES
NEAR 1.20 INCHES. FORCING THIS EVENING WILL BE FROM A COMBINED
EFFORT OF LAKE BREEZE BOUNDARIES AND UPPER LVL CONVERGENCE.
500-300MB QVECTORS SHOW FORCING (ASSOCIATED WITH THE 500MB
TROUGH)...CENTERED OVER NORTHERN MICHIGAN THIS EVENING BEFORE
SHIFTING EAST BY 06Z. CURRENT SFC OBS SHOWING SOME LAKE BREEZE
DEVELOPMENT THIS AFTN IN WEAK SYNOPTIC WIND FLOW AND AFTN TEMPS IN
THE MID 70S. THE LAKE BREEZE FORMATION HAS HELPED CONCENTRATE MOST
OF THE PCPN THIS AFTN TO INTERIOR PORTIONS OF NRN LWR MI. A
THUNDERSTORM IS ALSO POSSIBLE THIS EVENING...AS MODEL SOUNDINGS
AND HRRR DATA SHOW CAPE VALUES NEARING 1200 J/KG (AWAY FROM THE
GREAT LAKES). CAPES VALUES DIMINISH QUICKLY TO UNDER 500 J/KG ARND
03Z...AS DRIER AIR BEGINS TO FILTER INTO NRN MI. MODEL SOUNDINGS
AND MSTR PROGS SHOW MUCH DRIER AIRMASS TO DEVELOP OVER THE NRN
GREAT LAKES AFTER 03Z...THE RESULT OF A LARGE AREA OF CANADIAN
HIGH PRESSURE SETTLING FURTHER SOUTH INTO MI. 850/500MB RH FALLS
FROM 80 PCT TO UNDER 40 PCT...PWAT VALUES FALL FROM 1.20IN TO
0.50IN AND 850MB DEW PTS DRY FROM ARND 12C TO ARND 4C.
OVERALL WILL CONTINUE CURRENT FORECAST TREND OF SCATTERED SHOWERS
AND A FEW THUNDERSTORMS THIS EVENING...ENDING AROUND MIDNIGHT FOR
MOST LOCATIONS. WILL MENTION SOME PATCHY FOG OVERNIGHT AS TEMPS FALL
THROUGH THE 50S WHILE SFC DEW PTS SLOWLY DROP INTO THE LOWER 50S.
&&
.SHORT TERM...(FRIDAY THROUGH SUNDAY)
ISSUED AT 309 PM EDT THU JUN 25 2015
ZONAL FLOW BECOMING MORE AMPLIFIED OVER THE NEXT SEVERAL DAYS AS
QUASI-PERMANENT WESTERN CONUS RIDGE BUILDS WITH DOWNSTREAM
TROUGHING ACROSS THE EASTERN STATES. ALTHOUGH AIRMASS IS BECOMING
DRIER ON FRIDAY...STILL A HINT OF SOME HIGHER LOW LEVEL
MOISTURE/H9-H8 THETA-E RIDGING UP THE US-131 AND I-75 CORRIDORS IN
NORTHERN LOWER AND OVER PARTS OF EASTERN UPPER. THIS MOISTURE
COMBINED WITH SOME LAKE BREEZE CONVERGENCE...CAN/T RULE OUT AN
ISOLATED AFTERNOON SHOWER AND WILL ADD THIS TO THE FORECAST.
OTHERWISE...A TERRIFIC STRETCH OF SUMMER WEATHER FOR THE WEEKEND.
WILL STILL HAVE TO KEEP AN EYE ON THE UPPER LOW CLOSING OFF OVER
THE NORTHERN OHIO VALLEY ON SATURDAY AND PUSHING NORTH/NORTHEAST
INTO THE WESTERN LAKES. MODEL CONSENSUS STILL KEEPS THIS SYSTEM
JUST SOUTH/EAST OF OUR AREA...WHICH SEEMS PLAUSIBLE GIVEN THE LACK
OF DOWNSTREAM BLOCKING. BUT IT WILL BE VERY CLOSE FOR AREAS NEAR
SAGINAW BAY AND SOMETHING THAT COULD RESULT IN A FEW SHOWERS
CREEPING NORTHWARD TOWARD GLADWIN/ARENAC/IOSCO COUNTIES LATER
SATURDAY INTO SATURDAY NIGHT. NORTHERN MICHIGAN WILL BE BETWEEN
SYSTEMS ON SUNDAY...WITH UPPER LOW TO THE EAST AND NEXT UPSTREAM
SHORTWAVE DIVING THROUGH THE UPPER MIDWEST. THE END RESULT SHOULD
BE A FAIRLY NICE DAY WITH POSSIBLY A FEW MORE CLOUDS BUT
COMFORTABLE TEMPERATURES/DRY CONDITIONS.
&&
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 309 PM EDT THU JUN 25 2015
RIDGING OVER THE WESTERN THIRD OF THE CONUS WILL LEAD TO TROUGHING
OVER THE EASTERN TWO-THIRDS THROUGH MUCH...IF NOT ALL OF THE
EXTENDED PERIOD. THIS WILL LEAD TO SLIGHTLY COOLER THAN NORMAL
TEMPERATURES AND INCREASED CHANCES FOR SCATTERED RAIN SHOWERS AND
PERHAPS A FEW THUNDERSTORMS FROM SUNDAY NIGHT THROUGH AT LEAST
TUESDAY NIGHT (ALTHOUGH RECENT TRENDS HAVE INDICATED LIMITED
MOISTURE ACROSS NORTHERN MICHIGAN THROUGH THE MONDAY-TUESDAY
TIMEFRAME...SO BY ALL MEANS NEITHER DAY LOOKS LIKE A WASHOUT).
TOWARD THE VERY END OF THE PERIOD...LONG-RANGE GLOBAL MODEL GUIDANCE
SUGGESTS A MORE MOISTURE-RICH SYSTEM TO APPROACH THE MIDWEST/GREAT
LAKES...PERHAPS PROVIDING A BETTER CHANCE AT WIDESPREAD RAIN ACROSS
THE REGION. LOTS OF TIME TO IRON OF THE DETAILS ON IF/WHEN THAT`S
EXPECTED TO OCCUR.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 731 PM EDT THU JUN 25 2015
VFR CONDITIONS PERSIST ACROSS NRN LOWER MICHIGAN ALTHOUGH BKN-OVC MID
CLOUD WILL LINGER THROUGH THE EVENING HOURS BEFORE THINNING OUT
OVERNIGHT. SPOTTY HEATING OF THE DAY SHOWERS ARE OUT THERE AS WELL
BUT LARGELY IMPACTING INTERIOR NRN LOWER MICHIGAN. AS CLOUD COVER
THINS LATER TONIGHT...THERE IS A RISK FOR SOME FOG DEVELOPMENT
PARTICULARLY AT PLN AND APN...WITH MVFR CONDITIONS AND RISK FOR
IFR VSBYS OVERNIGHT.
WINDS GO NEARLY CALM BY LATER THIS EVENING...INCREASE AGAIN ON
FRIDAY BUT REMAIN UNDER 10 KNOTS FOR THE MOST PART. LAKE BREEZE
WIND DIRECTIONS WILL AGAIN DOMINATE THE TERMINAL SITES BY
AFTERNOON.
&&
.MARINE...
ISSUED AT 309 PM EDT THU JUN 25 2015
WINDS AND WAVES ARE TO REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA
THROUGH THE FORECAST PERIOD...AS A LARGE AREA OF CANADIAN HIGH
PRESSURE SINKS SOUTH OVER THE GREAT LAKES. MAINLY DRY CONDS CAN BE
EXPECTED IN THE NEARSHORE AREAS THROUGH THE FORECAST PERIOD. HOWEVER
SCATTERED SHOWERS AND A FEW THUNDERSTORMS WILL CONTINUE THIS EVENING
AS AN UPPER TROUGH EXITS THE STATE.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
NEAR TERM...SWR
SHORT TERM...KEYSOR
LONG TERM...GILLEN
AVIATION...ADAM
MARINE...SWR
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
353 PM EDT WED JUN 24 2015
.UPDATE...
ISSUED AT 1120 AM EDT WED JUN 24 2015
ONLY MINOR TWEAKS TO THE GOING FORECAST WITH THIS MORNINGS UPDATE.
A SHORTWAVE MOVING THROUGH NORTHERN MINNESOTA HAS SPREAD SOME
SHOWERS AND A FEW THUNDERSTORMS EAST-SOUTHEAST INTO WESTERN LAKE
SUPERIOR...BETWEEN THE APOSTLE ISLANDS AND ISLE ROYALE. EXPECT THIS
WAVE TO CONTINUE TO THE EAST AND SPREAD SHOWERS ACROSS THE NORTHERN
HALF OF THE KEWEENAW PENINSULA EARLY THIS AFTERNOON. THE QUESTION
FOR THIS AFTERNOON WILL BE THE AMOUNT OF SHOWER DEVELOPMENT THAT
WILL OCCUR OVER THE LAND AREAS...WHICH WILL BE AIDED BY LAKE
BREEZES. SURFACE DEWPOINTS AT THE 11AM WERE IN THE MID-UPPER
50S...BUT THE 12Z KGRB SOUNDING AND RAP ANALYSIS SOUNDINGS SHOW A
DECENT POCKET OF DRY AIR JUST ABOVE THE SURFACE AND THROUGH
800MB/7KFT. EXPECT THE SUN THAT IS OCCURRING OVER THE AREA TO AID
MIXING OF THAT DRIER AIR TO THE SURFACE OVER THE NEXT COUPLE OF
HOURS...WHICH WILL LIMIT THE INSTABILITY OVER THE AREA (DEWPOINTS
FALLING INTO THE LOWER 50S AND PROBABLY UPPER 40S TOWARDS THE
WISCONSIN BORDER). WHILE THERE WILL BE ENOUGH MOISTURE ABOVE THAT
DRY AIR TO DEVELOP CLOUDS AND LIKELY SOME SHOWERS...CONFIDENCE IS
LOWER ON WIDESPREAD SHOWERS AND HEAVIER RAIN. MODIFIED SOUNDINGS TO
EXPECTED AFTERNOON T/TD VALUES CONTINUES TO SHOW 500-600J/KG OF
MLCAPE...SO THUNDER REMAINS POSSIBLE ALONG WITH BRIEF GUSTY WINDS
DUE TO ABUNDANT LOW LEVEL DRY AIR PUSHING DCAPE VALUES OVER 800-
900J/KG OVER AT LEAST THE SOUTHERN HALF OF THE CWA. OVERALL EXPECT
THE GREATEST FOCUS OF SHOWERS TO BE OVER THE INTERIOR CENTRAL CWA
WHEN THEY DEVELOP AROUND MID AFTERNOON AND THEN MOVE TO THE
SOUTHEAST AROUND 20-25KTS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 411 AM EDT WED JUN 24 2015
A COLD FRONT AND A SUBTLE UPPER SHORTWAVE WILL MOVE THROUGH TODAY.
THESE FEATURES AND LAKE BREEZE FORMATION WILL PROVIDE FORCING FOR
CONVECTION MAINLY INLAND FROM THE GREAT LAKES. SBCAPE VALUES SHOULD
BE IN THE 500-800J/KG RANGE INLAND...WITH RELATIVELY WEAK SHEAR DUE
TO NEARLY CALM WINDS AT AND BELOW 800MB. INVERTED V SOUNDINGS WITH
DRY LOW LEVELS AND EVEN AN INDICATION OF AN EML MAY LEAD TO SOME
GUSTY WINDS UNDER ANY COLLAPSING STORMS...BUT SEVERE IS NOT EXPECTED
AS BEST CONVECTION SHOULD BE WHERE LOW LEVEL MOISTURE IS
GREATER...AWAY FROM THE WI BORDER. CONVECTION IS STILL EXPECTED
ALONG THE WI BORDER...JUST TO A LESSER EXTENT.
NOT SURE ON EXACTLY HOW THINGS PLAY OUT TONIGHT AS A SHORTWAVE
CURRENTLY NEAR THE MT/ALBERTA BORDER MOVES INTO OR NEAR THE CWA
WHILE A SFC TROUGH MOVES THROUGH. THE NAM...GFS...GEM AND ECMWF HAVE
PRECIP MOVING ALONG WITH THESE FEATURES THROUGH THE CWA...BUT A
COUPLE OF HIGH-RES MODELS DO NOT SHOW NEARLY THE EXTENT OF PRECIP.
AT THIS TIME...SIDED WITH THE MAJORITY OF MODELS AND HAVE HIGH
CHANCE TO LIKELY POPS...BUT IS IS ENTIRELY POSSIBLE THAT SOME
LOCATIONS WILL STAY DRY TONIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 426 AM EDT WED JUN 24 2015
SEVERAL PERIODS OF LIGHT SHOWERS ARE EXPECTED ACROSS UPPER MICHIGAN
DURING THE LONG TERM PERIOD...FIRST WITH LINGERING SHOWERS ON
THURSDAY FROM A PASSING SHORTWAVE...AND AGAIN DURING THE LATER PART
OF THE WEEKEND AND INTO EARLY NEXT WEEK.
THURSDAY...PASSING SHORTWAVE IN A NW FLOW COULD ALLOW SOME ISOLD TO
SCT SHOWERS TO LINGER DURING THE MORNING INTO EARLY AFTERNOON HOURS
AS MODELS GENERALLY SHOW 200-400 J/KG MLCAPE FOR INSTABILITY OVER
INLAND LOCATIONS. OTHERWISE...CONFLUENT FLOW ALOFT AHEAD OF BUILDING
RIDGE AND ASSOC MID-LVL Q-VECT DIV/SUBSIDENCE SHOULD GENERALLY LEAD
TO DRYING CONDITIONS ESPECIALLY BY LATE AFTERNOON.
TEMPORARY SPLIT-FLOW PATTERN DEVELOPING WILL ALLOW AN AREA OF SFC
HIGH PRESSURE TO DROP SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION
THU NIGHT AND PERSIST INTO SATURDAY RESULTING IN MAINLY DRY
CONDITIONS. 00Z NAM HINTS AT A FEW DIURNAL SHOWERS DEVELOPING ON
FRIDAY ALONG THE LAKE BREEZES BUT FOR NOW WL MAINTAIN DRY FCST AS
MID-LVLS WILL LIKELY BE TOO DRY FOR SHRA DEVELOPMENT. OTHERWISE
SHOULD SEE PARTLY CLOUDY TO MOSTLY CLEAR SKIES OVER THE AREA.
AMPLIFICATION OF UPSTREAM RIDGE OVER THE WRN CONUS ALONG WITH A
SERIES OF WAVES DIVING SOUTH THROUGH THE NRN AND CENTRAL PLAINS LATE
THIS WEEK WILL HELP AMPLIFY THE UPPER TROUGH OVER THE EASTERN HALF
OF THE CONUS FOR THIS WEEKEND. WHILE THE TROUGH WILL WEAKEN AND
SHIFT EAST INTO EARLY NEXT WEEK...A SERIES OF SHORTWAVES DROPPING
SOUTHEAST INTO THE GREAT LAKES REGION SUNDAY INTO TUESDAY WILL
REINFORCE THE UPPER TROUGH OVER THE GREAT LAKES REGION FOR NEXT
WEEK. THIS WILL YIELD NORMAL TO BELOW NORMAL TEMPERATURES ALONG WITH
PERIODS OF RAIN SHOWERS AND MAYBE EVEN A FEW THUNDERSTORMS.
ALSO SOMETHING TO WATCH...THE LATEST 00Z RUN OF THE ECMWF SHOWS 850
MB TEMPS PLUMMETING TO AROUND 1C BY NEXT TUE EVENING (THE LAST DAY
OF JUNE)...BRRR! THIS 00Z SOLUTION IS DEFINITELY MORE AMPLIFIED
WITH THE MID-UPR TROUGH INTO THE UPPER GREAT LAKES THAN EITHER THE
00Z GFS OR THE PREVIOUS 12Z ECMWF SOLN...ALLOWING A DIRECT PATH FOR
ARCTIC AIR TO DIVE SOUTH INTO THE REGION. AGAIN THIS IS JUST ONE
MODEL RUN...BUT IT WILL BE SOMETHING TO MONITOR OVER THE NEXT
SEVERAL MODEL RUNS AS A TREND TOWARD THIS MORE AMPLIFIED AND COLDER
SOLUTION COULD RESULT IN A BRIEF SPELL OF WELL BELOW NORMAL TEMPS
FOR THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 152 PM EDT WED JUN 24 2015
DIURNAL HEATING HAS LED TO THE DEVELOPMENT OF CLOUDS AND SHOWERS
OVER THE INTERIOR PORTIONS OF UPPER MICHIGAN...WHILE A WEAK UPPER
LEVEL DISTURBANCE MOVING EAST ACROSS THE NORTHERN HALF OF LAKE
SUPERIOR IS PRODUCING SHOWERS THERE TOO. EXPECT THE SHOWERS THAT
ARE AFFECTING KCMX TO PUSH EAST AND DIMINISH OVER THE NEXT FEW
HOURS. MEANWHILE...THE SHOWERS DEVELOPING OVER THE INTERIOR
WEST/CENTRAL U.P. WILL CONTINUE TO EXPAND IN COVERAGE AND AFFECT
KIWD/KSAW A LITTLE LATER THIS AFTERNOON. THERE IS ENOUGH
INSTABILITY FOR SOME RUMBLES OF THUNDER...BUT DIDN/T FEEL CONFIDENT
ENOUGH TO INCLUDE AT KSAW/KIWD AND WILL AMEND AS NECESSARY IF THEY
DEVELOP. FOR TONIGHT...ANOTHER DISTURBANCE WILL MOVE THROUGH THE
AREA AND IT SHOULD LEAD TO SHOWERS AT ALL THREE SITES. DEPENDING ON
THE RAIN...COULD SEE SOME PATCHY GROUND FOG DEVELOP AND HAVE
INCLUDED A BRIEF MVFR VSBY FOR KSAW DUE TO THAT. THAT DISTURBANCE
WILL SHIFT EAST OF THE AREA THROUGH THE DAY TOMORROW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 352 PM EDT WED JUN 24 2015
THERE WAS SOME LOW CLOUDS AND FOG OVER PORTIONS OF LAKE
SUPERIOR THIS MORNING. SOME OF THAT HAS DISSIPATED AND THE NORTHERN
PORTIONS HAVE BEEN COVERED BY CLOUDS. THUS...HAVE LIMITED CONFIDENCE
ON COVERAGE AND THICKNESS.
HIGH PRESSURE DROPPING SOUTH OVER LAKE SUPERIOR TONIGHT WILL LEAD
TO WINDS STAYING BELOW 20KTS THROUGH AT LEAST SATURDAY. THEN A
SERIES OF WEAK TROUGHS WILL DROP SOUTHEAST ACROSS LAKE SUPERIOR
SUNDAY INTO EARLY NEXT WEEK...BUT WINDS ARE STILL EXPECTED TO STAY
BELOW 20KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...SRF
SHORT TERM...TITUS
LONG TERM...VOSS
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
153 PM EDT WED JUN 24 2015
.UPDATE...
ISSUED AT 1120 AM EDT WED JUN 24 2015
ONLY MINOR TWEAKS TO THE GOING FORECAST WITH THIS MORNINGS UPDATE.
A SHORTWAVE MOVING THROUGH NORTHERN MINNESOTA HAS SPREAD SOME
SHOWERS AND A FEW THUNDERSTORMS EAST-SOUTHEAST INTO WESTERN LAKE
SUPERIOR...BETWEEN THE APOSTLE ISLANDS AND ISLE ROYALE. EXPECT THIS
WAVE TO CONTINUE TO THE EAST AND SPREAD SHOWERS ACROSS THE NORTHERN
HALF OF THE KEWEENAW PENINSULA EARLY THIS AFTERNOON. THE QUESTION
FOR THIS AFTERNOON WILL BE THE AMOUNT OF SHOWER DEVELOPMENT THAT
WILL OCCUR OVER THE LAND AREAS...WHICH WILL BE AIDED BY LAKE
BREEZES. SURFACE DEWPOINTS AT THE 11AM WERE IN THE MID-UPPER
50S...BUT THE 12Z KGRB SOUNDING AND RAP ANALYSIS SOUNDINGS SHOW A
DECENT POCKET OF DRY AIR JUST ABOVE THE SURFACE AND THROUGH
800MB/7KFT. EXPECT THE SUN THAT IS OCCURRING OVER THE AREA TO AID
MIXING OF THAT DRIER AIR TO THE SURFACE OVER THE NEXT COUPLE OF
HOURS...WHICH WILL LIMIT THE INSTABILITY OVER THE AREA (DEWPOINTS
FALLING INTO THE LOWER 50S AND PROBABLY UPPER 40S TOWARDS THE
WISCONSIN BORDER). WHILE THERE WILL BE ENOUGH MOISTURE ABOVE THAT
DRY AIR TO DEVELOP CLOUDS AND LIKELY SOME SHOWERS...CONFIDENCE IS
LOWER ON WIDESPREAD SHOWERS AND HEAVIER RAIN. MODIFIED SOUNDINGS TO
EXPECTED AFTERNOON T/TD VALUES CONTINUES TO SHOW 500-600J/KG OF
MLCAPE...SO THUNDER REMAINS POSSIBLE ALONG WITH BRIEF GUSTY WINDS
DUE TO ABUNDANT LOW LEVEL DRY AIR PUSHING DCAPE VALUES OVER 800-
900J/KG OVER AT LEAST THE SOUTHERN HALF OF THE CWA. OVERALL EXPECT
THE GREATEST FOCUS OF SHOWERS TO BE OVER THE INTERIOR CENTRAL CWA
WHEN THEY DEVELOP AROUND MID AFTERNOON AND THEN MOVE TO THE
SOUTHEAST AROUND 20-25KTS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 411 AM EDT WED JUN 24 2015
A COLD FRONT AND A SUBTLE UPPER SHORTWAVE WILL MOVE THROUGH TODAY.
THESE FEATURES AND LAKE BREEZE FORMATION WILL PROVIDE FORCING FOR
CONVECTION MAINLY INLAND FROM THE GREAT LAKES. SBCAPE VALUES SHOULD
BE IN THE 500-800J/KG RANGE INLAND...WITH RELATIVELY WEAK SHEAR DUE
TO NEARLY CALM WINDS AT AND BELOW 800MB. INVERTED V SOUNDINGS WITH
DRY LOW LEVELS AND EVEN AN INDICATION OF AN EML MAY LEAD TO SOME
GUSTY WINDS UNDER ANY COLLAPSING STORMS...BUT SEVERE IS NOT EXPECTED
AS BEST CONVECTION SHOULD BE WHERE LOW LEVEL MOISTURE IS
GREATER...AWAY FROM THE WI BORDER. CONVECTION IS STILL EXPECTED
ALONG THE WI BORDER...JUST TO A LESSER EXTENT.
NOT SURE ON EXACTLY HOW THINGS PLAY OUT TONIGHT AS A SHORTWAVE
CURRENTLY NEAR THE MT/ALBERTA BORDER MOVES INTO OR NEAR THE CWA
WHILE A SFC TROUGH MOVES THROUGH. THE NAM...GFS...GEM AND ECMWF HAVE
PRECIP MOVING ALONG WITH THESE FEATURES THROUGH THE CWA...BUT A
COUPLE OF HIGH-RES MODELS DO NOT SHOW NEARLY THE EXTENT OF PRECIP.
AT THIS TIME...SIDED WITH THE MAJORITY OF MODELS AND HAVE HIGH
CHANCE TO LIKELY POPS...BUT IS IS ENTIRELY POSSIBLE THAT SOME
LOCATIONS WILL STAY DRY TONIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 426 AM EDT WED JUN 24 2015
SEVERAL PERIODS OF LIGHT SHOWERS ARE EXPECTED ACROSS UPPER MICHIGAN
DURING THE LONG TERM PERIOD...FIRST WITH LINGERING SHOWERS ON
THURSDAY FROM A PASSING SHORTWAVE...AND AGAIN DURING THE LATER PART
OF THE WEEKEND AND INTO EARLY NEXT WEEK.
THURSDAY...PASSING SHORTWAVE IN A NW FLOW COULD ALLOW SOME ISOLD TO
SCT SHOWERS TO LINGER DURING THE MORNING INTO EARLY AFTERNOON HOURS
AS MODELS GENERALLY SHOW 200-400 J/KG MLCAPE FOR INSTABILITY OVER
INLAND LOCATIONS. OTHERWISE...CONFLUENT FLOW ALOFT AHEAD OF BUILDING
RIDGE AND ASSOC MID-LVL Q-VECT DIV/SUBSIDENCE SHOULD GENERALLY LEAD
TO DRYING CONDITIONS ESPECIALLY BY LATE AFTERNOON.
TEMPORARY SPLIT-FLOW PATTERN DEVELOPING WILL ALLOW AN AREA OF SFC
HIGH PRESSURE TO DROP SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION
THU NIGHT AND PERSIST INTO SATURDAY RESULTING IN MAINLY DRY
CONDITIONS. 00Z NAM HINTS AT A FEW DIURNAL SHOWERS DEVELOPING ON
FRIDAY ALONG THE LAKE BREEZES BUT FOR NOW WL MAINTAIN DRY FCST AS
MID-LVLS WILL LIKELY BE TOO DRY FOR SHRA DEVELOPMENT. OTHERWISE
SHOULD SEE PARTLY CLOUDY TO MOSTLY CLEAR SKIES OVER THE AREA.
AMPLIFICATION OF UPSTREAM RIDGE OVER THE WRN CONUS ALONG WITH A
SERIES OF WAVES DIVING SOUTH THROUGH THE NRN AND CENTRAL PLAINS LATE
THIS WEEK WILL HELP AMPLIFY THE UPPER TROUGH OVER THE EASTERN HALF
OF THE CONUS FOR THIS WEEKEND. WHILE THE TROUGH WILL WEAKEN AND
SHIFT EAST INTO EARLY NEXT WEEK...A SERIES OF SHORTWAVES DROPPING
SOUTHEAST INTO THE GREAT LAKES REGION SUNDAY INTO TUESDAY WILL
REINFORCE THE UPPER TROUGH OVER THE GREAT LAKES REGION FOR NEXT
WEEK. THIS WILL YIELD NORMAL TO BELOW NORMAL TEMPERATURES ALONG WITH
PERIODS OF RAIN SHOWERS AND MAYBE EVEN A FEW THUNDERSTORMS.
ALSO SOMETHING TO WATCH...THE LATEST 00Z RUN OF THE ECMWF SHOWS 850
MB TEMPS PLUMMETING TO AROUND 1C BY NEXT TUE EVENING (THE LAST DAY
OF JUNE)...BRRR! THIS 00Z SOLUTION IS DEFINITELY MORE AMPLIFIED
WITH THE MID-UPR TROUGH INTO THE UPPER GREAT LAKES THAN EITHER THE
00Z GFS OR THE PREVIOUS 12Z ECMWF SOLN...ALLOWING A DIRECT PATH FOR
ARCTIC AIR TO DIVE SOUTH INTO THE REGION. AGAIN THIS IS JUST ONE
MODEL RUN...BUT IT WILL BE SOMETHING TO MONITOR OVER THE NEXT
SEVERAL MODEL RUNS AS A TREND TOWARD THIS MORE AMPLIFIED AND COLDER
SOLUTION COULD RESULT IN A BRIEF SPELL OF WELL BELOW NORMAL TEMPS
FOR THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 152 PM EDT WED JUN 24 2015
DIURNAL HEATING HAS LED TO THE DEVELOPMENT OF CLOUDS AND SHOWERS
OVER THE INTERIOR PORTIONS OF UPPER MICHIGAN...WHILE A WEAK UPPER
LEVEL DISTURBANCE MOVING EAST ACROSS THE NORTHERN HALF OF LAKE
SUPERIOR IS PRODUCING SHOWERS THERE TOO. EXPECT THE SHOWERS THAT
ARE AFFECTING KCMX TO PUSH EAST AND DIMINISH OVER THE NEXT FEW
HOURS. MEANWHILE...THE SHOWERS DEVELOPING OVER THE INTERIOR
WEST/CENTRAL U.P. WILL CONTINUE TO EXPAND IN COVERAGE AND AFFECT
KIWD/KSAW A LITTLE LATER THIS AFTERNOON. THERE IS ENOUGH
INSTABILITY FOR SOME RUMBLES OF THUNDER...BUT DIDN/T FEEL CONFIDENT
ENOUGH TO INCLUDE AT KSAW/KIWD AND WILL AMEND AS NECESSARY IF THEY
DEVELOP. FOR TONIGHT...ANOTHER DISTURBANCE WILL MOVE THROUGH THE
AREA AND IT SHOULD LEAD TO SHOWERS AT ALL THREE SITES. DEPENDING ON
THE RAIN...COULD SEE SOME PATCHY GROUND FOG DEVELOP AND HAVE
INCLUDED A BRIEF MVFR VSBY FOR KSAW DUE TO THAT. THAT DISTURBANCE
WILL SHIFT EAST OF THE AREA THROUGH THE DAY TOMORROW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 411 AM EDT WED JUN 24 2015
WINDS WILL REMAIN BELOW 20KTS INTO THE MIDDLE OF NEXT WEEK. A LOW
PRESSURE SYSTEM DEVELOPING IN THE CENTRAL PLAINS TODAY WILL SLIDE E
THROUGH FRIDAY...WHILE ELONGATING OVER THE TENNESSEE VALLEY. A HIGH
OVER W ONTARIO THURSDAY MORNING WILL REMAIN OVER THE W GREAT LAKES
THROUGH SATURDAY. THIS RIDGE WILL SLIDE SLOWLY TO THE SE SATURDAY
NIGHT INTO SUNDAY AS A LOW SLIDES ACROSS N ONTARIO.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...SRF
SHORT TERM...TITUS
LONG TERM...VOSS
AVIATION...SRF
MARINE...TITUS
AREA FORECAST DISCUSSION...UPDATED
NWS MARQUETTE MI
1122 AM EDT WED JUN 24 2015
.UPDATE...
ISSUED AT 1120 AM EDT WED JUN 24 2015
ONLY MINOR TWEAKS TO THE GOING FORECAST WITH THIS MORNINGS UPDATE.
A SHORTWAVE MOVING THROUGH NORTHERN MINNESOTA HAS SPREAD SOME
SHOWERS AND A FEW THUNDERSTORMS EAST-SOUTHEAST INTO WESTERN LAKE
SUPERIOR...BETWEEN THE APOSTLE ISLANDS AND ISLE ROYALE. EXPECT THIS
WAVE TO CONTINUE TO THE EAST AND SPREAD SHOWERS ACROSS THE NORTHERN
HALF OF THE KEWEENAW PENINSULA EARLY THIS AFTERNOON. THE QUESTION
FOR THIS AFTERNOON WILL BE THE AMOUNT OF SHOWER DEVELOPMENT THAT
WILL OCCUR OVER THE LAND AREAS...WHICH WILL BE AIDED BY LAKE
BREEZES. SURFACE DEWPOINTS AT THE 11AM WERE IN THE MID-UPPER
50S...BUT THE 12Z KGRB SOUNDING AND RAP ANALYSIS SOUNDINGS SHOW A
DECENT POCKET OF DRY AIR JUST ABOVE THE SURFACE AND THROUGH
800MB/7KFT. EXPECT THE SUN THAT IS OCCURRING OVER THE AREA TO AID
MIXING OF THAT DRIER AIR TO THE SURFACE OVER THE NEXT COUPLE OF
HOURS...WHICH WILL LIMIT THE INSTABILITY OVER THE AREA (DEWPOINTS
FALLING INTO THE LOWER 50S AND PROBABLY UPPER 40S TOWARDS THE
WISCONSIN BORDER). WHILE THERE WILL BE ENOUGH MOISTURE ABOVE THAT
DRY AIR TO DEVELOP CLOUDS AND LIKELY SOME SHOWERS...CONFIDENCE IS
LOWER ON WIDESPREAD SHOWERS AND HEAVIER RAIN. MODIFIED SOUNDINGS TO
EXPECTED AFTERNOON T/TD VALUES CONTINUES TO SHOW 500-600J/KG OF
MLCAPE...SO THUNDER REMAINS POSSIBLE ALONG WITH BRIEF GUSTY WINDS
DUE TO ABUNDANT LOW LEVEL DRY AIR PUSHING DCAPE VALUES OVER 800-
900J/KG OVER AT LEAST THE SOUTHERN HALF OF THE CWA. OVERALL EXPECT
THE GREATEST FOCUS OF SHOWERS TO BE OVER THE INTERIOR CENTRAL CWA
WHEN THEY DEVELOP AROUND MID AFTERNOON AND THEN MOVE TO THE
SOUTHEAST AROUND 20-25KTS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 411 AM EDT WED JUN 24 2015
A COLD FRONT AND A SUBTLE UPPER SHORTWAVE WILL MOVE THROUGH TODAY.
THESE FEATURES AND LAKE BREEZE FORMATION WILL PROVIDE FORCING FOR
CONVECTION MAINLY INLAND FROM THE GREAT LAKES. SBCAPE VALUES SHOULD
BE IN THE 500-800J/KG RANGE INLAND...WITH RELATIVELY WEAK SHEAR DUE
TO NEARLY CALM WINDS AT AND BELOW 800MB. INVERTED V SOUNDINGS WITH
DRY LOW LEVELS AND EVEN AN INDICATION OF AN EML MAY LEAD TO SOME
GUSTY WINDS UNDER ANY COLLAPSING STORMS...BUT SEVERE IS NOT EXPECTED
AS BEST CONVECTION SHOULD BE WHERE LOW LEVEL MOISTURE IS
GREATER...AWAY FROM THE WI BORDER. CONVECTION IS STILL EXPECTED
ALONG THE WI BORDER...JUST TO A LESSER EXTENT.
NOT SURE ON EXACTLY HOW THINGS PLAY OUT TONIGHT AS A SHORTWAVE
CURRENTLY NEAR THE MT/ALBERTA BORDER MOVES INTO OR NEAR THE CWA
WHILE A SFC TROUGH MOVES THROUGH. THE NAM...GFS...GEM AND ECMWF HAVE
PRECIP MOVING ALONG WITH THESE FEATURES THROUGH THE CWA...BUT A
COUPLE OF HIGH-RES MODELS DO NOT SHOW NEARLY THE EXTENT OF PRECIP.
AT THIS TIME...SIDED WITH THE MAJORITY OF MODELS AND HAVE HIGH
CHANCE TO LIKELY POPS...BUT IS IS ENTIRELY POSSIBLE THAT SOME
LOCATIONS WILL STAY DRY TONIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 426 AM EDT WED JUN 24 2015
SEVERAL PERIODS OF LIGHT SHOWERS ARE EXPECTED ACROSS UPPER MICHIGAN
DURING THE LONG TERM PERIOD...FIRST WITH LINGERING SHOWERS ON
THURSDAY FROM A PASSING SHORTWAVE...AND AGAIN DURING THE LATER PART
OF THE WEEKEND AND INTO EARLY NEXT WEEK.
THURSDAY...PASSING SHORTWAVE IN A NW FLOW COULD ALLOW SOME ISOLD TO
SCT SHOWERS TO LINGER DURING THE MORNING INTO EARLY AFTERNOON HOURS
AS MODELS GENERALLY SHOW 200-400 J/KG MLCAPE FOR INSTABILITY OVER
INLAND LOCATIONS. OTHERWISE...CONFLUENT FLOW ALOFT AHEAD OF BUILDING
RIDGE AND ASSOC MID-LVL Q-VECT DIV/SUBSIDENCE SHOULD GENERALLY LEAD
TO DRYING CONDITIONS ESPECIALLY BY LATE AFTERNOON.
TEMPORARY SPLIT-FLOW PATTERN DEVELOPING WILL ALLOW AN AREA OF SFC
HIGH PRESSURE TO DROP SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION
THU NIGHT AND PERSIST INTO SATURDAY RESULTING IN MAINLY DRY
CONDITIONS. 00Z NAM HINTS AT A FEW DIURNAL SHOWERS DEVELOPING ON
FRIDAY ALONG THE LAKE BREEZES BUT FOR NOW WL MAINTAIN DRY FCST AS
MID-LVLS WILL LIKELY BE TOO DRY FOR SHRA DEVELOPMENT. OTHERWISE
SHOULD SEE PARTLY CLOUDY TO MOSTLY CLEAR SKIES OVER THE AREA.
AMPLIFICATION OF UPSTREAM RIDGE OVER THE WRN CONUS ALONG WITH A
SERIES OF WAVES DIVING SOUTH THROUGH THE NRN AND CENTRAL PLAINS LATE
THIS WEEK WILL HELP AMPLIFY THE UPPER TROUGH OVER THE EASTERN HALF
OF THE CONUS FOR THIS WEEKEND. WHILE THE TROUGH WILL WEAKEN AND
SHIFT EAST INTO EARLY NEXT WEEK...A SERIES OF SHORTWAVES DROPPING
SOUTHEAST INTO THE GREAT LAKES REGION SUNDAY INTO TUESDAY WILL
REINFORCE THE UPPER TROUGH OVER THE GREAT LAKES REGION FOR NEXT
WEEK. THIS WILL YIELD NORMAL TO BELOW NORMAL TEMPERATURES ALONG WITH
PERIODS OF RAIN SHOWERS AND MAYBE EVEN A FEW THUNDERSTORMS.
ALSO SOMETHING TO WATCH...THE LATEST 00Z RUN OF THE ECMWF SHOWS 850
MB TEMPS PLUMMETING TO AROUND 1C BY NEXT TUE EVENING (THE LAST DAY
OF JUNE)...BRRR! THIS 00Z SOLUTION IS DEFINITELY MORE AMPLIFIED
WITH THE MID-UPR TROUGH INTO THE UPPER GREAT LAKES THAN EITHER THE
00Z GFS OR THE PREVIOUS 12Z ECMWF SOLN...ALLOWING A DIRECT PATH FOR
ARCTIC AIR TO DIVE SOUTH INTO THE REGION. AGAIN THIS IS JUST ONE
MODEL RUN...BUT IT WILL BE SOMETHING TO MONITOR OVER THE NEXT
SEVERAL MODEL RUNS AS A TREND TOWARD THIS MORE AMPLIFIED AND COLDER
SOLUTION COULD RESULT IN A BRIEF SPELL OF WELL BELOW NORMAL TEMPS
FOR THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 741 AM EDT WED JUN 24 2015
MAINLY VFR CONDITIONS AS HIGH BASED SHOWERS AND POSSIBLY SOME
THUNDER THIS AFTERNOON AND EARLY EVENING. ADDITIONAL SHOWERS WILL
MOVE IN FROM THE WEST THIS EVENING/TONIGHT...BRINGING SOME LOWERING
CIGS LATE TONIGHT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 411 AM EDT WED JUN 24 2015
WINDS WILL REMAIN BELOW 20KTS INTO THE MIDDLE OF NEXT WEEK. A LOW
PRESSURE SYSTEM DEVELOPING IN THE CENTRAL PLAINS TODAY WILL SLIDE E
THROUGH FRIDAY...WHILE ELONGATING OVER THE TENNESSEE VALLEY. A HIGH
OVER W ONTARIO THURSDAY MORNING WILL REMAIN OVER THE W GREAT LAKES
THROUGH SATURDAY. THIS RIDGE WILL SLIDE SLOWLY TO THE SE SATURDAY
NIGHT INTO SUNDAY AS A LOW SLIDES ACROSS N ONTARIO.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...SRF
SHORT TERM...TITUS
LONG TERM...VOSS
AVIATION...TITUS
MARINE...TITUS
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1104 PM CDT TUE JUN 23 2015
.UPDATE...CLUSTER OF STORMS OVER TN WILL MAKE A MORE SOUTHWARD
PUSH AND LIKELY ENTER THE N-CENTRAL AND NE PORTIONS OF THE CWA AS IT
BEGINS TO WEAKEN. THE LATEST ANALYSIS ALONG WITH HRRR GUID SUPPORTS
THE STORM CLUSTER TO MAKE A MUCH FURTHER SOUTHWARD PROGRESS THAN
EXPECTED. LOW LEVEL TRAJECTORIES SUPPORT STORM PROPAGATION INTO THE
NE CWA WITH TIMING OF THE CLUSTER BETWEEN 1-2 AM. VERY ANOMALOUS
HEAT/HUMIDITY EXIST FOR THIS TIME OF EVENING AND SBCAPE IS HOLDING
AT ROUGHLY 4000 J/KG ALONG WITH SFC THETA E >360 K AND 850MB THETA E
AROUND 350 K. THESE INGREDIENTS SHOULD BE PLENTY TO SUPPORT THESE
STORMS AS THEY ENTER N/NE MS BUT EXPECTATIONS ARE FOR THINGS TO
BECOME LESS FAVORABLE AS THEY NEAR THE CWA BOARDER AND THE HWY 82
CORRIDOR. AT THIS POINT...JUST STRONG GUSTS ARE EXPECTED BUT SOME
SEVERE THREAT CANNOT BE TOTALLY RULED OUT. HOWEVER...WILL SIDE WITH
THE HRRR AND FORECAST WEAKENING AS IT NEARS THE CWA. THE FORECAST
HAS BEEN ADJUSTED TO INCREASE POPS. /CME/
&&
.AVIATION...VFR CONDITIONS WILL PREVAIL MORE HAZY HOT CONDITIONS.
LIKE THE PREV DAYS...THE HAZE LOOKS TO NOT IMPACT CONDITIONS WITH
VIS REMAINING AT 6SM OR GREATER. MORE OF AN OPPORTUNITY FOR
CONVECTION LOOKS TO EXIST AFTER 21Z WED AND VCTS WAS INCLUDED FOR
THAT PERIOD AT A FEW LOCATIONS. /CME/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 77 96 76 93 / 9 33 27 40
MERIDIAN 76 96 74 94 / 13 38 27 45
VICKSBURG 76 96 75 93 / 6 29 25 33
HATTIESBURG 76 97 75 93 / 5 48 37 50
NATCHEZ 75 94 75 91 / 5 37 32 35
GREENVILLE 76 98 77 95 / 12 18 14 31
GREENWOOD 76 95 76 94 / 25 21 16 34
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...HEAT ADVISORY FROM 11 AM TO 7 PM CDT WEDNESDAY FOR MSZ026>033-
036>039-042>046-048>052.
HEAT ADVISORY UNTIL 7 PM CDT WEDNESDAY FOR MSZ018-019-025-034-
035-040-041-047-053.
LA...HEAT ADVISORY UNTIL 7 PM CDT WEDNESDAY FOR LAZ007>009-015-016-
023-025.
AR...HEAT ADVISORY UNTIL 7 PM CDT WEDNESDAY FOR ARZ074-075.
&&
$$
CME
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1202 AM CDT Wed Jun 24 2015
.SHORT TERM...(This Evening through Thursday)
Issued at 200 PM CDT TUE JUN 23 2015
A front has stalled out across the area. This frontal boundary
shows up very nicely on the visible satellite imagery and surface
obs this afternoon. The front was currently located from near
Nevada to near Eminence. This front will start to slowly back up
northward later this evening and tonight. There is a complex of
storms northwest of the Kansas City area which are moving east-
southeastward.
The latest Hi-Res models suggest this complex if it holds together
may clip our central Missouri counties late this afternoon and
early evening. The HRRR and the ARW continues to suggest a few
isolated showers and storms developing near the stalled out
frontal boundary across central Missouri into the eastern Missouri
Ozarks. There will be a limited risk for a strong storm or two
with small hail and gusty winds as the main threat. Any convection
should either dissipate or move off to the east of the area after sunset.
Wednesday and Thursday will be hot and humid with the upper level
ridge nosing in a bit over the area. High temperatures may be a
couple degrees warmer than today with most areas in the lower to
middle 90s. Heat index will be around 100. Southwest winds will be
gusty up to 30 mph for areas west of Highway 65.
.LONG TERM...(Thursday Night through Tuesday)
Issued at 200 PM CDT TUE JUN 23 2015
A stronger shortwave will move through the Midwest and Ohio River
Valley region on Friday. This feature will begin to carve out a
trough across the eastern U.S. while an upper level ridge builds
across the western U.S. A cold front will move down into the
region starting Thursday night. Showers and thunderstorms will
begin to impact portions of central Missouri late Thursday night
and area wide by Friday. Will not rule out a few strong storms
possible Friday with gusty winds and small hail the main threats.
The front will clear through the area by Friday night with rain
ending from north to south.
The weekend is shaping up to be extremely nice. Drier air will
move into the area with dewpoints in the 50s. The latest model
guidance came in a degree or two cooler with lows Saturday night
and Sunday night in the upper 50s to lower 60s. Highs will be in
the upper 70s to lower 80s and Mostly sunny skies. Looks like the
below average temperatures will continue into early next week.
Another weak front may try to move into the area by Monday night
with a few showers and storms possible.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday Night)
Issued at 1159 PM CDT TUE JUN 23 2015
Mostly clear skies and VFR conditions will continue through
Wednesday evening. Winds will increase out of the southwest on
Wednesday and will become somewhat gusty around Joplin.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Schaumann
AREA FORECAST DISCUSSION
NWS BILLINGS MT
328 PM MDT WED JUN 24 2015
.SHORT TERM...VALID FOR THU AND FRI...
THUNDERSTORMS REMAIN THE MAIN FOCUS IN THE SHORT TERM.
THUNDERSTORM CHANCES THE REST OF TODAY HAVE SHIFTED TOWARDS BIG
HORN AND SHERIDAN COUNTIES. MUCH OF THE ENERGY WHAT WAS EXPECTED
TO BE IN THE EASTERN ZONES HAS BEEN DISSIPATED BY CONVECTION
EARLIER THIS MORNING. MUCH OF THE HI RES GUIDANCE SHOWS LIMITED
CAPE VALUES FROM CUSTER AND POWDER RIVER COUNTIES EASTWARD. ACROSS
BIG HORN AND SHERIDAN COUNTIES CAPE VALUES REACH 1000 TO 1200 J/KG
ALONG WITH SHEAR VALUES FROM 0 TO 6 KM REACHING 50 TO 60 KNOTS.
MID MORNING RUNS OF THE HRRR...ALONG WITH THE 12Z NSSL WRF...SHOWS
ACTIVITY DEVELOPING OVER THE THE SNOWY MOUNTAINS AND THEN
STRENGTHENING ACROSS BIG HORN COUNTY IN THE BETTER ENVIRONMENT.
THE CAVEAT TO THIS IS THE HIGH CLOUDS OVER MUCH OF THE AREA AND
THE LOW CLOUDS THAT HAVE HUNG AROUND IN SHERIDAN INTO EARLY
AFTERNOON. THE LATEST RUNS OF THE HRRR ARE RATHER QUIET THIS
AFTERNOON. EVEN WITH THE SHORTWAVE MOVING THROUGH THE
AREA...MODELS ARE NOT GIVING A HIGH DEGREE OF CONFIDENCE IN THE
CHANCES FOR THUNDERSTORMS. GIVEN THE SHEAR AND CAPE...AT LEAST
ACROSS PART OF THE AREA...IF STORMS CAN DEVELOP THEY HAVE THE
POTENTIAL TO BE STRONG TO SEVERE.
THE SETUP FOR THURSDAY DOES NOT LOOK AS GOOD FOR SEVERE
WEATHER...ALTHOUGH SOME STORMS STILL COULD BE STRONGER. THE AREA
WILL BEGIN TO SEE THE INFLUENCE OF THE RIDGE THAT IS BUILDING INTO
THE WESTERN US. THIS WILL RESULT IN SUBTLE RISING HEIGHTS. THIS
WILL HELP TO DECREASE RAIN CHANCES SOME. THAT SAID ANOTHER
SHORTWAVE WILL MOVE ACROSS SOUTHEASTERN MONTANA...WHICH WILL
PLACES THE BEST CHANCES FOR CONVECTION AGAIN FROM POWDER RIVER AND
CUSTER COUNTIES EAST.
FRIDAY THE AREA IS WILL UNDER THE INFLUENCE OF THE BUILDING RIDGE
AND WILL SEE RAIN CHANCES DIMINISH. TEMPERATURES WILL ALSO BEGIN
THEIR INCREASE INTO THE WEEKEND. REIMER
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
VERY HOT WEATHER IS EXPECTED THIS WEEKEND AND INTO EARLY NEXT WEEK
THANKS TO A LARGE 500-MB RIDGE THAT WILL DEVELOP OVER THE WESTERN
UNITED STATES. THE MULTI-MODEL CONSENSUS THAT WE USED TO BUILD
THE FORECAST CALLS FOR HIGHS WELL INTO THE 90S F SATURDAY AND
SUNDAY...AND WE ARE STILL CALLING FOR HIGHS OF 100 F IN MANY SPOTS
ON MONDAY WHEN 700-MB TEMPERATURES PEAK AT +15 TO +18 C. THE 12
UTC GFS AND ECMWF SUGGEST THAT THE RIDGE WILL RETROGRADE A BIT
NEXT TUESDAY AND WEDNESDAY...WHICH WILL SHOULD LET HIGHS DROP BACK
A BIT INTO THE LOWER TO MIDDLE 90S F. THE FORECAST IS ESSENTIALLY
A DRY ONE AT THIS POINT SINCE MODEL OUTPUT HAS ONLY A WEAK SIGNAL
OF MONSOONAL MOISTURE REACHING THE REGION UNDERNEATH THE LARGE
RIDGE ALOFT. SCHULTZ
&&
.AVIATION...
A FEW SHOWERS AND THUNDERSTORMS ARE POSSIBLE ACROSS SOUTHERN MT
AND NORTH CENTRAL WY THROUGH TONIGHT...BUT OUR CONFIDENCE IS LOW
WITH REGARD TO THE COVERAGE OF THAT ACTIVITY. SUB-VFR CONDITIONS
ARE POSSIBLE IN ANY STORMS THAT DEVELOP...BUT VFR WEATHER WILL
OTHERWISE PREVAIL THROUGH TONIGHT. SCHULTZ
&&
.PRELIMINARY POINT TEMP/POPS...
THU FRI SAT SUN MON TUE WED
-----------------------------------------------------------
BIL 060/084 060/091 061/093 063/096 066/100 068/094 064/090
22/T 10/U 00/U 01/U 11/U 11/B 11/U
LVM 053/086 051/093 053/095 056/098 056/100 059/093 056/093
21/B 10/U 01/U 11/U 11/B 11/B 11/B
HDN 060/086 057/093 060/095 063/099 064/101 066/095 063/091
33/T 20/B 00/U 00/U 00/G 11/B 11/U
MLS 059/083 059/088 061/093 062/095 063/097 066/092 063/089
23/T 21/B 00/U 00/U 00/U 11/B 11/U
4BQ 059/081 058/086 058/090 060/093 062/095 065/092 061/088
34/T 31/B 00/U 00/U 11/U 11/B 11/U
BHK 056/080 057/084 058/089 059/089 061/091 062/086 059/084
24/T 31/B 10/U 00/U 00/U 11/B 12/T
SHR 057/080 054/085 055/088 056/091 057/093 061/091 058/086
33/T 21/B 10/U 11/U 11/U 11/B 11/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
557 PM MDT THU JUN 25 2015
.AVIATION...
00Z TAF CYCLE
SCATTERED THUNDERSTORMS WILL CONTINUE UNTIL AROUND 03Z BEFORE
GRADUALLY DIMINISHING. AN UPPER LEVEL NLY WIND SPEED MAX MOVING
THROUGH ERN NM THIS EVENING AND OVERNIGHT WILL KEEP CONVECTION
GOING FROM CENTRAL HIGHLANDS AND SOUTH-CENTRAL MTNS EAST TO EAST-
CENTRAL PLAINS UNTIL AROUND 07Z INCLUDING KTCC AND POSSIBLY AS FAR
SOUTH AS KROW. BRIEF PERIOD OF MODERATE EAST WINDS POSSIBLE AT
KABQ BTWN 02Z-05Z. ANOTHER ROUND OF AFTERNOON AND EVENING
CONVECTION EXPECTED FRIDAY BUT STORMS OVER CENTRAL AND EASTERN
AREAS WILL BE MARKEDLY STRONGER DUE TO A STRONG BACKDOOR COLD
FRONT DROPPING INTO ERN PLAINS.
33
&&
.PREV DISCUSSION...317 PM MDT THU JUN 25 2015...
.SYNOPSIS...
AN ACTIVE PERIOD OF WEATHER WILL BE THE RULE THROUGH AT LEAST
MONDAY. STORMS SHOULD EXPAND IN COVERAGE TONIGHT ACROSS THE
EASTERN PLAINS...PERHAPS RESULTING IN AN EAST CANYON WIND IN THE
RIO GRANDE VALLEY. STORM COVERAGE WILL INCREASE FURTHER ON FRIDAY
THANKS TO A BACK DOOR COLD FRONT PUSHING THROUGH THE GAPS OF THE
CENTRAL MOUNTAIN CHAIN. MOISTURE BEHIND THE FRONT WILL FUEL
THUNDERSTORMS THROUGH THE WEEKEND INTO MONDAY. SLOW STORM MOTIONS
AND HEAVY RAIN MAY LEAD TO FLASH FLOODING...ESPECIALLY ACROSS
VULNERABLE DRAINAGES. A DOWNTREND IN STORM COVERAGE IS POSSIBLE
TUESDAY AND WEDNESDAY...BUT STORM ACTIVITY WILL QUICKLY RAMP BACK
UP AGAIN ON THURSDAY THANKS TO ANOTHER BACK DOOR FRONT AND
MOISTURE SURGE.
&&
.DISCUSSION...
AS EXPECTED...ANOTHER CROP OF SHOWERS AND THUNDERSTORMS HAVE
DEVELOPED ACROSS THE HIGHER TERRAIN. AS THE UPPER HIGH REBUILDS
OVER THE FOUR CORNERS...STEERING FLOW WILL CONTINUE TO TAKE STORMS
TOWARD THE SOUTH. THUS FAR...STORMS HAVE BEEN MOVING JUST
ENOUGH...AND HAVE BEEN PULSEY ENOUGH...TO NOT CAUSE TOO MANY WATER
ISSUES.
HI-RES MODELS SHOWING STORMS FIRING ALONG A BOUNDARY NEAR THE E
NM/E CO BORDER THROUGH THE REMAINDER OF THE AFTN. APPEARS THAT
STORMS MAY GET SOMEWHAT ORGANIZED INTO A CLUSTER...FORMING A COLD
POOL...WITH STORMS PROPAGATING SOUTHWARD ACROSS THE PLAINS ALONG
THE OUTFLOW BOUNDARY. THE QUESTION WILL BE HOW FAR SOUTH THE
STORMS CAN HOLD TOGETHER BEFORE THE OUTFLOW BOUNDARY OUTRACES THE
STORMS. HRRR KEEPS STORMS TOGETHER AS FAR SOUTH AS ROSWELL...BUT
THE NAM SHOWS PRECIP FALLING APART SHORT OF THERE.
NONETHELESS...HAVE INCREASED POPS ACROSS THE EASTERN PLAINS
TONIGHT. THE SMALL DISTURBANCE NOTED ON WV SATELLITE IMAGERY
NOSING INTO NE NM ATTM SHOULD AID IN STORM DEVELOPMENT AND
MAINTENANCE. DEPENDING ON IF STORMS FIRE ALONG THE EAST SLOPES OF
THE SANDIAS...AS THE HRRR SUGGESTS...COULD SEE A PRETTY
STRONG...BUT SHORT-LIVED...EAST WIND INTO THE RGV.
FRIDAY LOOKS TO BE MORE ACTIVE THAN TODAY...ESPECIALLY ACROSS THE
PLAINS. THOUGH THE REMNANT BOUNDARY FROM TONIGHTS CONVECTION
SHOULD BE SOMEWHERE ACROSS THE PLAINS TOMORROW...A BACK DOOR
FRONT...LIKELY CONVECTIVELY AIDED... WILL SLIDE DOWN THE PLAINS
EARLY FRIDAY. THUS...MULTIPLE ROUNDS OF STORMS WILL BE
POSSIBLE...INITIALLY WITH THE FRONT...AND THEN AGAIN LATER IN THE
DAY AFTER THE FRONT NUDGES UP TO THE CENTRAL MTN CHAIN...IGNITING
STORMS...AND THOSE STORMS SHOULD TRAVEL S OR SE-WARD OUT INTO THE
PLAINS ONCE AGAIN. MEANWHILE...THE FRONT WILL PUSH THROUGH THE
CENTRAL MOUNTAIN CHAIN BY EARLY-MID AFTN...SPILLING LOW LEVEL
MOISTURE WESTWARD. THUS...EXPECT ANOTHER ROUND OF STORMS ACROSS
WESTERN NM AS WELL...PERHAPS WITH BETTER COVERAGE THAN TODAY. EAST
CANYON WINDS SHOULD ONCE AGAIN BE PRETTY STRONG.
WITH ABUNDANT MOISTURE /PWATS LIKELY ABOVE 1 INCH AREAWIDE/...
NORTH TO SOUTH STEERING FLOW...AND LOW LEVEL S TO SELY FLOW
THROUGH THE WEEKEND...AN ACTIVE PERIOD MIGHT BE AN UNDERSTATEMENT.
STEERING FLOW WILL REMAIN WEAK...AND STORMS CONTAINING HEAVY RAIN
IS A CERTAINTY. THIS SPELLS A RECIPE FOR FLASH FLOOD
POTENTIAL...AND A FLASH FLOOD WATCH MAY BE NEEDED. MONDAY LOOKS TO
BE MORE OF THE SAME...THOUGH A WEAK BOUNDARY WILL ALSO NOSE INTO
NE NM AS WELL.
ON TUESDAY AND WEDNESDAY... DRIER AIR LOOKS TO CIRCLE AROUND THE
HIGH AND OVER NM. THOUGH THIS SHOULD LIMIT CONVECTIVE COVERAGE
OVER THE FRI-SUN PERIOD...THERE WILL STILL BE ENOUGH MOISTURE
AROUND FOR THE HIGH TERRAIN TO SEE SOME ACTION.
ACTIVITY RAMPS BACK UP ON THURSDAY THANKS TO ANOTHER BACK DOOR
FRONT REPLENISHING MOISTURE ACROSS THE STATE. CURRENT INDICATIONS
IS THAT THIS FRONT WILL ALSO PUSH THROUGH THE GAPS OF THE CENTRAL
MTN CHAIN...SETTING THE STAGE FOR NUMEROUS SHRA/TSRA THURS...AND
FRIDAY. ANOTHER FRONT...OR PERHAPS OUTFLOW BOUNDARY FROM
CONVECTION MAY ARRIVE ON THE 4TH OF JULY. LOOKS LIKE MOTHER NATURE
WILL PROVIDE HER OWN FIREWORKS AGAIN THIS YEAR.
34
&&
.FIRE WEATHER...
NO REAL BIG CHANGES. A MORE SIGNIFICANT PUSH OF
MOISTURE FROM NORTHEAST TO SOUTHWEST WILL OCCUR TONIGHT THROUGH
FRIDAY NIGHT VIA A BACK DOOR COLD FRONT. THIS SURGE WILL KICK OFF
A WET PHASE TO THE MONSOON PERIOD.
AS FAR AS THE REST OF TODAY...HIT AND MISS STORMS CONTAINING WETTING
RAIN WILL IMPACT MOST OF THE AREA THROUGH THIS EVENING. THE MAIN
FOCUS AREA FOR WETTING RAIN WILL BE FOUND ACROSS EASTERN/CENTRAL
AREAS. THUNDERSTORMS SHOULD BLEED INTO THE EARLY MORNING HOURS ON
FRIDAY. EXPECT GOOD TO EXCELLENT HUMIDITY RECOVERIES. GUSTY OUTFLOW
WIND WILL BE ASSOCIATED WITH SOME OF THE STORMS. THE LOWEST HUMIDITY
WILL BE FOUND ACROSS THE FAR NORTHWEST. STORMS WILL TEND TO MOVE
TOWARDS A SOUTHERLY DIRECTION AND GENERALLY BE SLOW MOVING.
AS THE UPPER RIDGE SHIFTS FURTHER NORTHWEST OF THE STATE ON FRIDAY.
THIS WILL ALLOW A VIGOROUS BACK DOOR COLD FRONT TO SWEEP UNDERNEATH
AND REENERGIZE MOISTURE SUPPLIES WITHIN THE PERIPHERY OF THE UPPER
HIGH. HUMIDITY VALUES WILL GO UP AND TEMPERATURES WILL LOWER. A
FOCUS FOR WIDESPREAD WETTING RAIN WILL BE FOUND ALONG THIS FRONTAL
PUSH. CENTRAL AND EASTERN AREAS SHOULD BE FAVORED FRIDAY/FRIDAY
NIGHT AND THEN SHIFT WESTWARD ON SATURDAY. WETTING THUNDERSTORM
COVERAGE SHOULD LOWER SLIGHTLY ON SUNDAY BUT STILL BE PRETTY
WIDESPREAD. HIGHER HUMIDITY AND COOLER TEMPERATURES WILL ALSO
PREVAIL DURING THIS PERIOD. OUTFLOW WIND GUSTS WILL BE AROUND BUT
NOT AS STRONG COMPARED TO A DRIER ATMOSPHERIC ENVIRONMENT.
RESIDUAL IMPACTS OF THE MOISTURE TRAPPED WITHIN THE UPPER HIGH WILL
CONTINUE EARLY NEXT WEEK. ANOTHER BACK DOOR COLD FRONT IS POSSIBLE
SUNDAY NIGHT. A GRADUAL DRYING TREND IS EXPECTED TUESDAY AND COULD
POSSIBLY TREND INTO WEDNESDAY. BY LATE WEEK ANOTHER BACK DOOR COLD
FRONT SHOULD REPLENISH THE MOISTURE LOST EARLIER IN THE WAY AND
INCREASE WETTING THUNDERSTORM COVERAGE.
OVERALL VENTILATION WILL BE THE LOWEST DURING THE WEEKEND DUE TO
REDUCED MIXING HEIGHTS...PLENTY OF CLOUD COVER AND LOWER TRANSPORT
WINDS.
50
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
48
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
200 PM EDT WED JUN 24 2015
.SYNOPSIS...
HIGH PRESSURE WILL RESULT IN DRY WEATHER WITH INCREASING AMOUNTS
OF SUNSHINE THIS AFTERNOON. A PASSING WAVE OF LOW PRESSURE WILL
BRING SHOWERS THROUGH THE REGION LATE THURSDAY. OUR PATTERN WILL
REMAIN SLIGHTLY COOLER THAN NORMAL...AND UNSETTLED WITH PERIODIC
CHANCES OF SHOWERS THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
9 AM UPDATE...
VISIBLE SATELLITE IMAGERY SHOWS AN OVC LAYER OF STRATOCUMULUS
ACROSS NORTH CENTRAL NY TO THE CATSKILLS...EASTERN SOUTHERN TIER
OF NY AND SOUTH INTO THE POCONOS AND SCRANTON/WILKES BARRE AREAS
OF PA. THIS LAYER WAS BTWN 1800 AND 3000 FEET AND SLOWLY
DEVELOPING TO THE W-SW AS A LOW-LEVEL NW FLOW ASCENDS UP THE HILLS
OF C NY AND NE PA AND SATURATES OUT. THIS IS AIDED BY SOME
BOUNDARY LAYER HEATING. AS THE BNDRY LAYER HEATS AND GROWS INTO
THE AFTERNOON DRIER AIR FROM ABOVE WILL ENTRAIN DOWNWARD AND MUCH
OF THE CLOUDINESS WILL BREAK UP. MODEL SOUNDINGS FROM
NAM...GFS...RAP AND HRRR ALL SEEM TO QUICK TO MIX OUT THE OVC
LAYER. THE NAM4KM MODEL SOUNDINGS APPEAR TO HAVE THE BEST HANDLE
ON THE PRESENT SITUATION AND DELAY THE CLOUDS BREAKING UP INTO
THE AFTERNOON. SO WILL FOLLOW NAM 4KM. LOOKING AT THE CU RULE
WHICH TAKES THE 850 MB TEMP AND SUBTRACTS THE 1000 MB DWPT THE GFS...NAM
AND ECMWF SUGGEST A SCT CUMULUS LAYER THIS AFTERNOON AS THE BNDRY
LAYER REACHES ITS MAX HGHT PROBABLY ARND 5-6 KFT. SO WILL KEEP PC
SKIES BY MID AFTERNOON AS WE BELIEVE THE PRESENT OVC SC LAYER WILL
EVOLVE INTO SCT CU BY 19-20Z. ALSO ADJUSTED TEMPS DOWN A TAD TO
ACCOUNT FOR MORE CLOUD COVER. HARD TO BELIEVE IT IS LATE JUNE HERE
AT BGM AS THE SKY LOOKS VERY MUCH LIKE NOVEMBER NOW!!
4 AM UPDATE...
NORTHWEST WINDS WILL CONTINUE TO ADVECT IN A DRY AIR MASS...AS
HIGH PRESSURE SPREADS IN FROM THE MIDWEST. PLENTY OF SUNSHINE CAN
BE EXPECTED...WITH HIGHS TODAY MAINLY IN THE 70S...A FEW TO
SEVERAL DEGREES SHORT OF CLIMATOLOGY. DEWPOINTS WILL ONLY BE LOW
TO MID 50S...WHICH FOR MOST IS VERY COMFORTABLE.
QUIET CONDITIONS PERSIST TONIGHT WITH A MAINLY CLEAR SKY...THEN
INCREASING HIGH THIN CLOUDS TOWARDS DAWN AHEAD OF THE NEXT
DISTURBANCE...WITH LOWS IN THE 50S.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
4 AM UPDATE...
THURSDAY STARTS OFF FAIRLY QUIET...BUT A NORTHERN STREAM SUMMER
CLIPPER OF SORTS...WILL ARRIVE FROM THE UPPER MIDWEST MID TO LATE
AFTERNOON. MEANWHILE...SOUTHERN STREAM WARM FRONT WILL ATTEMPT TO
LIFT NORTHWARD FROM THE MIDATLANTIC STATES BUT WILL FALL SHORT.
BAROCLINIC LIFT WILL OCCUR NORTH OF THAT WARM FRONT...AS THE
NORTHERN STREAM WAVE ALSO PASSES. HOWEVER...INSTABILITY LOOKING
MORE DOUBTFUL...AND THUS EXPECTING MAINLY JUST SHOWERS OR EVEN
STRATIFORM RAIN INSTEAD OF THUNDER. I INCLUDE ONLY A SLIGHT CHANCE
OF THUNDER IN NORTHEAST PA AT THIS TIME...TO ACCOMPANY LIKELIHOOD
OF SHOWERS LATE THURSDAY INTO THURSDAY EVENING. FURTHER
NORTH...CHANCES DROP OFF...TO THE POINT THAT SOME PORTIONS OF
CENTRAL NY MAY RECEIVE VERY LITTLE RAIN FROM THIS SYSTEM.
00Z NAM APPEARS TO BE SUFFERING FROM CONVECTIVE FEEDBACK GIVEN
THE FAIR AMOUNT OF STABILITY...AND THUS ITS QPF AMOUNTS LOOK
UNREASONABLE. SOMETHING ON THE ORDER OF UP TO A FEW TENTHS OF AN
INCH...OR CONSENSUS OF NON-NAM MODELS...APPEARS MORE PROBABLE...AND
THOSE AMOUNTS FOCUSED MAINLY TWIN TIERS SOUTHWARD.
WITH TIME...EASTERN UPPER TROUGH WILL BE SETTING UP. SO WHILE
CHANCES OF ADDITIONAL SHOWERS FRIDAY-FRIDAY NIGHT ARE NOT THAT
HIGH...WE COULD STILL HAVE SCATTERED SHOWERS POPPING UP WITH WEAK
SHORTWAVES EMBEDDED IN THE LARGER DEVELOPING TROUGH...COMBINED
WITH DIURNAL HEATING.
TEMPERATURES THROUGH THE PERIOD WILL GENERALLY BE A FEW TO SEVERAL
DEGREES BELOW NORMAL VALUES.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
115 PM EDT UPDATE...
CLOSELY FOLLOWED WPC GUIDANCE.
A VERY ACTIVE PATTERN CONTINUES AND WILL REMAIN IN PLACE THRU THE
END OF THE FORECAST PERIOD. THIS PATTERN CONSISTS OF TROUGHING OVER
THE EAST AND RIDGING OVER THE WEST. KEPT A CHANCE FOR PRECIP OVER
THE CWA THRU THE WHOLE PERIOD. MULT WAVES WILL RIDE AROUND THE
TROUGH AND CREATE ENOUGH UPPR LVL SUPPORT FOR SHOWERS. THIS PATTERN
WILL ALSO CREATE CLOUDY SKIES ALONG WITH BELOW NORMAL TEMPS FOR THIS
TIME OF YR.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
SCT-BKN CUMULUS HAS EVOLVED FROM AN MVFR STRATOCUMULUS DECK OF
THIS MORNING WITH THE STRONG LATE SUMMER SUN. CLOUD BASES WERE UP
TO 5 KFT AND MAY EVEN REACH 6 KFT. HAVE TAFS ALL VFR SCT CUMULUS
FOR THE AFTERNOON. SKIES WILL CLEAR OUT QUICKLY BY SUNSET. THEN WE
WILL SEE HIGH CLOUDS STREAM IN ACRS OUR NRN TAF SITES BTWN 5-6Z
AND THESE CLOUDS WILL SPREAD SOUTHWARD BY 12Z-13Z ACRS REST OF TAF
SITES. AN ALTOCUMULUS DECK ARND 10 TO 12 KFT WILL REACH KRME AND
KSYR BY 12-13Z. THE REST OF THE NY TAFS CUD SEE SOME PATCHY MID
CLDS UNDER BKN-OVC CIRRUS.
WITH MAINLY CLEAR SKIES MOST OF THE NGT...WE EXPECT IFR FG TO
DEVELOP AT LEAST FOR A FEW HOURS AT KELM. CROSS-OVER TEMPS WILL
FALL TO ABT 52-53F THIS PM WITH MINS EXPECTED TO BE CLOSE TO 50F
AT KELM. OUR LOCAL ELM FOG CHECKLIST RETURNS IFR FOG AT LEAST A
FEW HOURS OR SO BETWEEN 9 AND 13Z AND THUS HAVE PATCHY IFR FG AT
KELM. REST OF TAFS VFR THRU 18Z THU.
WINDS WILL BE NW ARND 10 KNOTS THIS AFTERNOON AND LIGHT WESTERLY
AFTER SUNSET AND W-SW 5-10 KNOTS THU AM.
.OUTLOOK...
THURS NGT/FRI/SAT/SUN/MON...CHANCE OF SHRA AND ASSOCIATED
RESTRICTIONS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PCF
NEAR TERM...DJN/MDP
SHORT TERM...MDP
LONG TERM...MDP
AVIATION...DJN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
907 AM EDT WED JUN 24 2015
.SYNOPSIS...
HIGH PRESSURE WILL RESULT IN DRY WEATHER WITH INCREASING AMOUNTS
OF SUNSHINE THIS AFTERNOON. A PASSING WAVE OF LOW PRESSURE WILL
BRING SHOWERS THROUGH THE REGION LATE THURSDAY. OUR PATTERN WILL
REMAIN SLIGHTLY COOLER THAN NORMAL...AND UNSETTLED WITH PERIODIC
CHANCES OF SHOWERS THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
9 AM UPDATE...
VISIBLE SATELLITE IMAGERY SHOWS AN OVC LAYER OF STRATOCUMULUS
ACROSS NORTH CENTRAL NY TO THE CATSKILLS...EASTERN SOUTHERN TIER
OF NY AND SOUTH INTO THE POCONOS AND SCRANTON/WILKES BARRE AREAS
OF PA. THIS LAYER WAS BTWN 1800 AND 3000 FEET AND SLOWLY
DEVELOPING TO THE W-SW AS A LOW-LEVEL NW FLOW ASCENDS UP THE HILLS
OF C NY AND NE PA AND SATURATES OUT. THIS IS AIDED BY SOME
BOUNDARY LAYER HEATING. AS THE BNDRY LAYER HEATS AND GROWS INTO
THE AFTERNOON DRIER AIR FROM ABOVE WILL ENTRAIN DOWNWARD AND MUCH
OF THE CLOUDINESS WILL BREAK UP. MODEL SOUNDINGS FROM
NAM...GFS...RAP AND HRRR ALL SEEM TO QUICK TO MIX OUT THE OVC
LAYER. THE NAM4KM MODEL SOUNDINGS APPEAR TO HAVE THE BEST HANDLE
ON THE PRESENT SITUATION AND DELAY THE CLOUDS BREAKING UP INTO
THE AFTERNOON. SO WILL FOLLOW NAM 4KM. LOOKING AT THE CU RULE
WHICH TAKES THE 850 MB TEMP AND SUBTRACTS THE 1000 MB DWPT THE GFS...NAM
AND ECMWF SUGGEST A SCT CUMULUS LAYER THIS AFTERNOON AS THE BNDRY
LAYER REACHES ITS MAX HGHT PROBABLY ARND 5-6 KFT. SO WILL KEEP PC
SKIES BY MID AFTERNOON AS WE BELIEVE THE PRESENT OVC SC LAYER WILL
EVOLVE INTO SCT CU BY 19-20Z. ALSO ADJUSTED TEMPS DOWN A TAD TO
ACCOUNT FOR MORE CLOUD COVER. HARD TO BELIEVE IT IS LATE JUNE HERE
AT BGM AS THE SKY LOOKS VERY MUCH LIKE NOVEMBER NOW!!
4 AM UPDATE...
NORTHWEST WINDS WILL CONTINUE TO ADVECT IN A DRY AIR MASS...AS
HIGH PRESSURE SPREADS IN FROM THE MIDWEST. PLENTY OF SUNSHINE CAN
BE EXPECTED...WITH HIGHS TODAY MAINLY IN THE 70S...A FEW TO
SEVERAL DEGREES SHORT OF CLIMATOLOGY. DEWPOINTS WILL ONLY BE LOW
TO MID 50S...WHICH FOR MOST IS VERY COMFORTABLE.
QUIET CONDITIONS PERSIST TONIGHT WITH A MAINLY CLEAR SKY...THEN
INCREASING HIGH THIN CLOUDS TOWARDS DAWN AHEAD OF THE NEXT
DISTURBANCE...WITH LOWS IN THE 50S.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
4 AM UPDATE...
THURSDAY STARTS OFF FAIRLY QUIET...BUT A NORTHERN STREAM SUMMER
CLIPPER OF SORTS...WILL ARRIVE FROM THE UPPER MIDWEST MID TO LATE
AFTERNOON. MEANWHILE...SOUTHERN STREAM WARM FRONT WILL ATTEMPT TO
LIFT NORTHWARD FROM THE MIDATLANTIC STATES BUT WILL FALL SHORT.
BAROCLINIC LIFT WILL OCCUR NORTH OF THAT WARM FRONT...AS THE
NORTHERN STREAM WAVE ALSO PASSES. HOWEVER...INSTABILITY LOOKING
MORE DOUBTFUL...AND THUS EXPECTING MAINLY JUST SHOWERS OR EVEN
STRATIFORM RAIN INSTEAD OF THUNDER. I INCLUDE ONLY A SLIGHT CHANCE
OF THUNDER IN NORTHEAST PA AT THIS TIME...TO ACCOMPANY LIKELIHOOD
OF SHOWERS LATE THURSDAY INTO THURSDAY EVENING. FURTHER
NORTH...CHANCES DROP OFF...TO THE POINT THAT SOME PORTIONS OF
CENTRAL NY MAY RECEIVE VERY LITTLE RAIN FROM THIS SYSTEM.
00Z NAM APPEARS TO BE SUFFERING FROM CONVECTIVE FEEDBACK GIVEN
THE FAIR AMOUNT OF STABILITY...AND THUS ITS QPF AMOUNTS LOOK
UNREASONABLE. SOMETHING ON THE ORDER OF UP TO A FEW TENTHS OF AN
INCH...OR CONSENSUS OF NON-NAM MODELS...APPEARS MORE PROBABLE...AND
THOSE AMOUNTS FOCUSED MAINLY TWIN TIERS SOUTHWARD.
WITH TIME...EASTERN UPPER TROUGH WILL BE SETTING UP. SO WHILE
CHANCES OF ADDITIONAL SHOWERS FRIDAY-FRIDAY NIGHT ARE NOT THAT
HIGH...WE COULD STILL HAVE SCATTERED SHOWERS POPPING UP WITH WEAK
SHORTWAVES EMBEDDED IN THE LARGER DEVELOPING TROUGH...COMBINED
WITH DIURNAL HEATING.
TEMPERATURES THROUGH THE PERIOD WILL GENERALLY BE A FEW TO SEVERAL
DEGREES BELOW NORMAL VALUES.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
115 PM EDT UPDATE...
CLOSELY FOLLOWED WPC GUIDANCE.
A VERY ACTIVE PATTERN CONTINUES AND WILL REMAIN IN PLACE THRU THE
END OF THE FORECAST PERIOD. THIS PATTERN CONSISTS OF TROUGHING OVER
THE EAST AND RIDGING OVER THE WEST. KEPT A CHANCE FOR PRECIP OVER
THE CWA THRU THE WHOLE PERIOD. MULT WAVES WILL RIDE AROUND THE
TROUGH AND CREATE ENOUGH UPPR LVL SUPPORT FOR SHOWERS. THIS PATTERN
WILL ALSO CREATE CLOUDY SKIES ALONG WITH BELOW NORMAL TEMPS FOR THIS
TIME OF YR.
&&
.AVIATION /13Z WEDNESDAY THROUGH SUNDAY/...
PATCH OF SC OVER ERN NY BRINGING MVFR CIGS TO SYR AND RME THIS
MRNG. BRIEF FOG PSBL WEST OF THE CLDS...ESP AT ITH...OTRW HIPRES
WILL BRING MAINLY CLR SKIES AND VFR CONDS TO THE TAF SITES FOR THE
NEXT 24 HRS. WINDS WILL BE WEST BHD YSTRDYS COLD FNT...GNRLY 10
KTS OR LESS.
.OUTLOOK...
THURS AFTN/FRI/SAT/SUN...CHANCE OF SHRA AND ASSOCIATED
RESTRICTIONS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PCF/DJN
NEAR TERM...DJN/MDP
SHORT TERM...MDP
LONG TERM...MDP
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
955 PM EDT THU JUN 25 2015
.SYNOPSIS... A COUPLE OF DISTURBANCES IN THE NORTHWEST FLOW ALOFT
WILL IMPACT THE AREA TONIGHT. AN UPPER LEVEL TROUGH DIGGING
SOUTHEAST INTO THE OHIO VALLEY ON FRIDAY WILL DEEPEN ALONG THE
EASTERN SEABOARD OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 955 PM THURSDAY...
...SEVERE THUNDERSTORM WATCH 353 CONTINUES UNTIL MIDNIGHT EDT
TONIGHT AREA FROM THE TRIANGLE TO THE NORTHEAST..
THERE HAS BEEN NEARLY CONTINUOUS CONVECTIVE INITIATION THIS
EVENING.. ALONG WHAT MAY HAVE BEEN THE REMNANTS OF OUTFLOW FROM
EARLY MORNING CONVECTION STRETCHING FROM BURLINGTON TO RALEIGH.
MOST OF THE STORMS HAVE BEEN RATHER INTENSE IN WHAT ULTIMATELY WAS A
HIGH CAPE ENVIRONMENT ONCE STRONG HEATING FINALLY TOOK HOLD. WHILE
THESE STORMS HAVE FINALLY BEGUN MOVE SOUTHEAST AND WEAKEN..AT LEAST
TEMPORARILY...THERE IS ANOTHER ROUND OF CONVECTION POSSIBLE AS
MERGING SUPERCELLS OVER CENTRAL VA AND/OR OUTFLOW FROM STORMS OVER
EASTERN KY APPROACH THE AREA. WHILE A SMALL AREA BETWEEN THE TRIAD
AND TRIANGLE HAS BEEN WORKED OVER AND THERE WILL BE SOME SMALL
NOCTURNAL COOLING IN THE NEXT COUPLE OF HOURS...THERE SHOULD STILL
BE PLENTY OF ENERGY FOR STORMS TO FEED ON...POSSIBLY EVEN REMAINING
ROOTED NEAR THE SURFACE. DEEP LAYER SHEAR WILL BE STRONG...35-
40KT...AND BACKED SOUTHEASTERLY SURFACE WINDS WILL MAINTAIN AT LEAST
A SMALL AREA OF ENHANCED HELICITY AND A TORNADO THREAT OVER THE
NORTHERN COASTAL PLAIN. OTHERWISE...THE PRIMARY CONCERN WILL BE
DAMAGING WINDS WITH BOWING SEGMENTS. THE LATEST HRRR BRINGS A
CLUSTER OF STORMS THROUGH BETWEEN 04Z AND 09Z...WHICH EXTENDS BEYOND
THE CURRENT SEVERE WATCH THAT ENDS AT 05Z...SO SOME CONSIDERATION
WILL HAVE TO BE GIVEN TO THAT AS WELL. LOWS TONIGHT WILL BE IN THE
LOWER 70S ONCE CONVECTION CLEARS THE AREA.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 310 PM THURSDAY...
THE AREA WILL BE IN BETWEEN TWO SYSTEMS DURING THE DAY ON FRIDAY AND
WITH SOME BRIEF SHORT WAVE RIDGING MOVING OVERHEAD...PRECIP SHOULD
BE AT A MINIMUM DURING THE DAY (COMPARED TO RECENT DAYS). HOWEVER...
THIS WILL BE SHORT LIVED AS OUR NEXT SHORT WAVE APPROACHES DURING
THE EVENING OR OVERNIGHT HOURS. PRECIP CHANCES WILL QUICKLY INCREASE
THROUGH THE OVERNIGHT HOURS. GIVEN THE FACT THAT THIS WILL OCCUR
OVERNIGHT...AM NOT EXPECTING MUCH IN THE WAY OF SEVERE POTENTIAL
SINCE INSTABILITY WILL BE WEAK. HOWEVER...SHEAR WILL BEGIN TO
INCREASE THROUGH THE EARLY MORNING HOURS OF SATURDAY AS A DEEP LAYER
TROUGH GETS CLOSER...THEREFORE A FEW STORMS WILL HAVE THE POTENTIAL
TO BECOME MORE ORGANIZED.
ANOTHER HOT DAY IS EXPECTED ON FRIDAY (LIKELY OUR LAST FOR THIS
CURRENT HEAT WAVE)...WITH MID TO UPPER 90S EXPECTED. HEAT INDEX
VALUES MAY APPROACH OR EXCEED 105 DEGREES IN THE SOUTHEAST PORTIONS
OF THE CWA...POSSIBLY NECESSITATING A HEAT ADVISORY. OVERNIGHT LOWS
WILL GENERALLY BE IN THE LOW/MID 70S.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 310 PM THURSDAY...
AN UPPER LOW WILL DEEPEN OVER THE OHIO VALLEY/GREAT LAKES AS A
RATHER DEEP TROUGH DIGS SOUTH INTO THE TN VALLEY. AN ASSOCIATED COLD
FRONT WILL APPROACH AND CROSS THE REGION SATURDAY/SATURDAY NIGHT.
ALTHOUGH NOT OVERLY IMPRESSIVE...BULK SHEAR VALUES WILL BE ON THE
ORDER OF 30 KNOTS. MORE UNCERTAIN WILL BE THE AMOUNT OF INSTABILITY
SINCE CONVECTION SHOULD BE ONGOING SATURDAY MORNING...THUS LIMITING
THE AMOUNT OF INSOLATION. REGARDLESS...MODELS PROG MARGINAL
DESTABILIZATION AND SOME STORMS MAY BECOME STRONG TO SEVERE...WITH
DAMAGING WINDS AND HAIL BEING THE PRIMARY THREATS. PRECIP WILL
GRADUALLY COME TO AN END LATE SATURDAY NIGHT/EARLY SUNDAY THE FRONT
MOVES EAST OF THE AREA. HIGHS ON SATURDAY WILL BE TEMPERED SOME BY
THE CLOUDS/PRECIP...WITH MOSTLY MID/UPPER 80S TO LOWER 90S EXPECTED.
COOLER AND DRIER AIR WILL FILTER IN BEHIND THE FRONT FOR SUNDAY AND
INTO EARLY NEXT WEEK. THIS WILL RESULT IN MOSTLY DRY CONDITIONS AND
TEMPS ACTUALLY BEING BELOW NORMAL. LONGWAVE TROUGHING WILL SET UP
OVER THE EAST COAST THROUGH MUCH OF NEXT WEEK...WITH IT BECOME
SLIGHTLY MORE AMPLIFIED BY THE MIDDLE OF THE WEEK. GIVEN THIS SET
UP...ANY SHORT WAVE CROSSING THE REGION WILL BRING A CHANCE FOR
SHOWERS/STORMS...ESPECIALLY WEDNESDAY/THURSDAY. TEMPS WILL GRADUALLY
MODERATE...WITH MOSTLY NEAR TO SLIGHTLY ABOVE NORMAL EXPECTED.
&&
.AVIATION /00Z THURSDAY THROUGH TUESDAY/...
AS OF 735 PM THURSDAY
24 HOUR TAF PERIOD: CONVECTION CURRENTLY OCCURRING IN THE VICINITY
OF KRDU WITH A THUNDERSTORM HEADED FOR THE TERMINAL AT THIS TIME.
EXPECT THIS ACTIVITY TO CONTINUE FOR THE NEXT COUPLE OF HOURS. OTHER
TERMINALS NOT AFFECTED AT THIS TIME BUT KRWI AND KFAY COULD SEE
VICINITY SHOWERS OR STORMS OVER THE NEXT COUPLE OF HOURS.
A SECOND ROUND OF CONVECTION COMING OUT OF EASTERN KY COULD AFFECT
NORTHERN COUNTIES LATER DURING THE OVERNIGHT HOURS WITH KRWI THE
MOST LIKELY TO SEE STRONGER CONVECTION BUT KRDU AND TO A LESSER
EXTENT KGSO AND KINT ARE NOT COMPLETELY OUT OF THE PICTURE EITHER.
WITH THIS LINE OF STORMS STRONG WINDS GENERALLY OUT OF THE NORTHWEST
ARE PROBABLE. AFTER STORMS PASS OVERNIGHT...THERE IS A POTENTIAL FOR
SOME FOG/LOW STRATUS IN THE NORTHEAST. OTHERWISE CONDITIONS WILL
RETURN TO VFR AND SHOULD REMAIN THERE THROUGH THE END OF THE TAF
PERIOD.
LONG TERM: THE BEST CHANCE FOR ADVERSE CONDITIONS IN THE LONG TERM
WILL BE ON SATURDAY WITH A FRONTAL SYSTEM PROGRESSING ACROSS THE
AREA EXPECTED TO BRING WIDESPREAD RAINFALL TO THE AREA. SUB-VFR
CONDITIONS ARE PROBABLE THROUGH SUNDAY MORNING BEFORE CLEARING OUT
FROM NW TO SE WITH A RETURN TO VFR CONDITIONS PERSISTING THROUGH
EARLY NEXT WEEK.
&&
.CLIMATE...
REC
DAY MAX YR
RDU RECORDS
06/25 100 1952
06/26 102 1952
GSO RECORDS
06/25 101 1914
06/26 102 1914
FAY RECORDS
06/25 102 1914
06/26 101 1951
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RAH
NEAR TERM...ELLIS/22
SHORT TERM...KRD
LONG TERM...KRD
AVIATION...ELLIS
CLIMATE...RAH
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
347 PM EDT WED JUN 24 2015
.SYNOPSIS...
HOT AND HUMID CONDITIONS WILL PERSIST THROUGH THE END OF THE WEEK
WITH ISOLATED SHOWERS AND THUNDERSTORMS PRIMARILY DURING THE
AFTERNOONS AND EVENINGS. MUCH COOLER TEMPERATURES ALONG WITH A
BETTER CHANCE OF SHOWERS AND THUNDERSTORMS WILL DEVELOP THIS
WEEKEND. A DRYING TREND WILL BEGIN NEXT WEEK AS FRONT STALLED IN
THE AREA DISSIPATES AND HIGH PRESSURE RETURNS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 200 PM WEDNESDAY...A HEAT ADVISORY REMAINS IN EFFECT
THROUGH EARLY THIS EVENING AS TEMPS SOAR INTO AND THROUGH THE 90S
ONCE AGAIN AND COMBINE WITH A VERY HUMID AIR MASS TO CREATE
DANGEROUS HEAT. VISIBLE IMAGERY KEEPING MOSTLY SUNNY SKIES OVER
MUCH OF THE AREA VERY EARLY THIS AFTERNOON BUT CU WAS DEVELOPING
AND CLUSTERING MAINLY OVER NORTHERN TIER COUNTIES WITH SOME ALSO
EVIDENT ALONG SEA BREEZE BOUNDARY.
NORTHERLY WINDS REACHING DOWN TO NORTH/SC BORDER EARLY THIS AFTN
AS WEAKENING COLD FRONT DROPS SLOWLY SOUTH. THIS WILL HELP TO
ADVECT SLIGHTLY DRIER AIR IN FROM THE N-NW AND WILL CREATE A
TIGHTER GRADIENT FLOW AND ENHANCED LOW LEVEL CONVERGENCE. OVERALL
IT WILL JUST PRODUCE A WIND SHIFT TO A MORE N-NE DIRECTION BEHIND
IT AS IT REACHES DOWN ALONG THE NC/SC BORDER CUTTING ACROSS OUR
LOCAL FORECAST AREA THIS AFTERNOON. THE MUCH DRIER AIR WILL
REMAIN WELL TO THE NORTHWEST AS SW FLOW AT THE SURFACE CONTINUES
TO KEEP A MOISTURE RICH AIR MASS OVER MUCH OF LOCAL FORECAST
AREA....WITH DEWPOINT TEMPS INTO THE 70S AND PCP WATER VALUES
NEAR 2 INCHES. ML CAPE VALUES WERE REACHING CLOSE TO 4000 J/KG
WITH LI VALUES TO -11. THIS UNSTABLE ENVIRONMENT WILL INCREASE THE
POTENTIAL FOR CONVECTIVE DEVELOPMENT THIS AFTERNOON. OVERALL THE
FORCING WILL BE SHALLOW WITH STEEP LOW LEVEL LAPSE RATES TO
INITIATE STORM DEVELOPMENT THIS AFTERNOON.
THE FOCUS OF CONVECTION WILL BE ALONG THIS SFC BOUNDARY AS IT
SHIFTS SLIGHTLY SOUTH THROUGH THIS AFTERNOON AND COMBINES WITH
ENHANCED CONVERGENCE ALONG SEA BREEZE BOUNDARY AS IT ADVANCES
INLAND ALONG WITH OTHER LOCALIZED BOUNDARIES. WITH ALL THIS BEING
SAID...THERE IS NOT MUCH IN THE WAY OF UPPER LEVEL SUPPORT AS WE
REMAIN ON THE TOP OF RIDGE ALOFT. THE SW FLOW FROM THE SFC THROUGH
THE LOW LEVEL FLOW WILL VEER TO BECOME MORE WESTERLY WHICH WILL
AID IN DOWNSLOPE FLOW AND HEATING...SOME DRYING AND WILL ALSO HELP
TO KEEP SEA BREEZE PINNED CLOSER TO THE COAST INITIALLY. AS
HEATING INCREASES EXPECT CU AND SHWRS/TSTMS TO FORM ALONG
CONVERGENT BOUNDARIES. SPC HAS KEPT OUR AREA IN A MARGINAL RISK
FOR SVR STORMS AS A MODERATELY UNSTABLE AIR MASS YIELDS STRONG
UPDRAFT/DOWNDRAFT GROWTH WITH POTENTIAL FOR ISOLATED DAMAGING
WINDS. THE HRRR SHOWS MAIN FOCUS ALONG WEAKENING FRONT FROM
MARLBORO TO PENDER COUNTIES BY 18Z AND OTHER MORE ISOLATED
CONVECTIVE DEVELOPMENT ALONG SEA BREEZE FROM GEORGETOWN COUNTY UP
THROUGH THE GRAND STRAND INTO THE CAPE FEAR AREA. THE STEERING
FLOW WILL BE OUT OF THE NW WHICH WILL PUSH ALL STORMS SOUTHEAST
AND TOWARD THE COAST WITH OTHER STORMS DEVELOPING ALONG COLLIDING
BOUNDARIES.
MOST OF THIS ACTIVITY WILL END THIS EVENING AS CONVECTION WILL BE
ALMOST EXCLUSIVELY DIURNALLY FORCED. KEPT SOME LINGERING POPS INTO
LATE THIS EVENING BUT NOT TOO CONFIDENT AS TO HOW MUCH WILL LINGER
AFTER DARK. MIN TEMPS TONIGHT WILL AGAIN BE QUITE WARM...DROPPING
ONLY TO AROUND 80 AT THE BEACHES...75 WELL INLAND.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...LONG LIVED MID LEVEL RIDGE WILL START SHOWING
SIGNS OF WEAKENING DURING THE PERIOD ALTHOUGH THE HEAT AND HUMIDITY
WILL CONTINUE. RIDGE HOLDS ON THU BUT STARTS TO BREAK DOWN LATER FRI
AS 5H TROUGH APPROACHES FROM THE NORTHWEST. AT THE SURFACE THE
BERMUDA HIGH AND PIEDMONT TROUGH REMAIN IN PLACE ALONG WITH DAILY
DEVELOPMENT OF THE AFTERNOON SEA BREEZE. DEEP MOISTURE REMAINS IN
PLACE WITH PRECIPITABLE WATER VALUES RUNNING BETWEEN 1.75 AND 2
INCHES. MID LEVEL LAPSE RATES ARE STEEP ENOUGH FOR DEVELOPMENT OF
MODERATE TO STRONG UPDRAFTS WITH ONLY A SHALLOW LAYER OF LESS
FAVORABLE LAPSE RATES TO OVERCOME. THE PROBLEM IS THE HEIGHT OF THIS
SHALLOW STABLE LAYER WHICH IS BASED BETWEEN 7K AND 8K FT. THIS MAY
BE TOO HIGH FOR THE SEA BREEZE AND PIEDMONT TROUGH TO OVERCOME ON
THEIR OWN. ATMOSPHERE MAY REQUIRE SOME BOUNDARY INTERACTION...WITH
LEFT OVER CONVECTIVE BOUNDARIES...AND HEATING BEFORE DEEPER
CONVECTION IS ABLE TO DEVELOP. WILL CARRY CHC POP EACH AFTERNOON BUT
FAVOR A LATER TIMING GIVEN THE AFOREMENTIONED LIMITATIONS.
TEMPERATURES WILL CONTINUE TO RUN WELL ABOVE CLIMO WITH HIGHS IN THE
MID 90S AND LOWS IN THE MID TO UPPER 70S.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...MID LEVEL TROUGH AND STALLED SURFACE BOUNDARY
WILL RESULT IN UNSETTLED WEATHER FOR MUCH OF THE PERIOD. LARGE 5H
TROUGH SETS UP OVER THE EASTERN CONUS BUT THE TROUGHS AXIS WILL
REMAIN WEST OF THE AREA THROUGH TUE. COMBINATION OF DIURNAL
HEATING...DEEP AND MOIST SOUTHWEST FLOW...AND AN OCCASIONAL
SHORTWAVE ROTATING AROUND THE BASE OF THE TROUGH WILL LEAD TO AN
INCREASE IN SHOWER AND THUNDERSTORM ACTIVITY ACROSS THE AREA. BEST
CHANCES WILL BE SAT INTO SUN AS THE TROUGH ARRIVES AND PUSHES A COLD
FRONT INTO THE AREA. DEEP MOISTURE PRESENT AHEAD OF THE TROUGH ALONG
WITH SHORTWAVE ENERGY WARRANTS AT LEAST HIGH CHC TO LIKELY POP SAT.
MOISTURE LINGERS THROUGH THE FIRST HALF OF SUN BUT LOW LEVEL
INSTABILITY DECREASES. WILL HOLD ONTO PRECIP CHANCES SUN AND SUN
NIGHT BUT TREND POP DOWNWARD...ESPECIALLY SUN NIGHT.
MID LEVEL DRY AIR WORKS IN FOR LATE SUN THROUGH TUE AS A LOBE OF THE
5H TROUGH EJECTS NORTHEAST...WITH WEAK SUBSIDENCE OVER THE
SOUTHEAST. LONGWAVE TROUGH AXIS REMAINS WEST OF THE AREA AND THE
DISSIPATING FRONT WILL REMAIN STALLED OVER OR JUST EAST OF THE AREA.
THE LACK OF MID LEVEL MOISTURE WILL HINDER DEEPER CONVECTION BUT
STILL EXPECT AT LEAST SOME DEVELOPMENT. PLAN TO MAINTAIN INHERITED
SILENT POP MON AND TUE GIVEN AN UNFAVORABLE ENVIRONMENT AND A FAIR
AMOUNT OF UNCERTAINTY.
HIGH TEMPERATURES WILL BE NEAR TO SLIGHTLY BELOW CLIMO DUE TO THE
INCREASED MOISTURE/CLOUD COVER ALONG WITH THE POTENTIAL FOR MORE
CONVECTION. LOWS WILL CONTINUE TO RUN ABOVE CLIMO.
&&
.AVIATION /17Z WEDNESDAY THROUGH SUNDAY/...
AS OF 12Z...TERMINALS ARE VFR THIS MORNING AND VFR WILL LIKELY
CONTINUE THROUGH 18Z. WINDS WILL BE SW-W 5-10 KTS EXCEPT BECOMING
SSW AT THE COASTAL TERMINALS MID MORNING ON.
THUNDERSTORMS RESULTING IN TEMPO REDUCED FLIGHT CONDITIONS AND GUSTY
WINDS WILL BE THE BIGGEST THREATS TO AVIATION MAINLY THIS AFTERNOON
AND EVENING. THUNDERSTORMS SHOULD DEVELOP AFTER 17Z INITIALLY ALONG
A WEAK FRONT NEAR KLBT TO N OF KILM. DRY AIR IN THE MID LEVELS
SHOULD ALLOW FOR LESS ACTIVITY TO DEVELOP ELSEWHERE. SOME BOUNDARIES
COULD THROWN OFF TO THE SOUTH ALLOWING THUNDERSTORMS TO DEVELOP
FURTHER S IN THE AFTERNOON AND EVENING. CONFIDENCE OF THUNDERSTORM
OCCURRENCE IS HIGHEST N.
ACTIVITY DISSIPATES DURING THE EVENING. WINDS MAY BE VARIABLE IN THE
EVENING/EARLY MORNING WHERE STORMS HAVE OCCURRED...BUT GENERALLY
LIGHT SW WINDS CAN BE EXPECTED OVERNIGHT WITH VFR CONDITIONS.
EXTENDED OUTLOOK...ISOLATED SHOWERS AND STORMS THURSDAY. MODERATE
CONFIDENCE FOR SCATTERED TO NUMEROUS SHOWERS AND STORMS FRIDAY
AFTERNOON THROUGH SUNDAY WITH MVFR/IFR CONDITIONS AND POSSIBLE HEAVY
RAIN.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 200 PM WEDNESDAY...WINDS WILL REMAIN OUT OF THE SW BETWEEN
ATLANTIC HIGH PRESSURE AND TROUGH INLAND. SHOULD REMAIN BETWEEN 10
AND 15 KTS OVER MOST OF THE WATERS...BUT WILL SEE SOME HIGHER
GUSTS OVER 20 KTS. SEAS WILL BE 2 TO 4 FT WITH THE SW WIND CHOP
DOMINATING. WINDS WILL SPIKE UP AND REMAIN GUSTIER THROUGH EARLY THIS
EVENING AS SEA BREEZE ENHANCES THE FLOW.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...BERMUDA HIGH AND PIEDMONT TROUGH COMBO
WILL MAINTAIN SOUTHWEST FLOW ACROSS THE WATERS THROUGH THE PERIOD.
GRADIENT WILL INCREASE THU INTO FRI WITH SOLID 20 KT DEVELOPING
THU NIGHT AND CONTINUING THROUGH THE END OF THE PERIOD. SEAS 3 TO
4 FT AT THE START OF THE PERIOD WILL BUILD TO 3 TO 5 FT AND
POSSIBLY 4 TO 6 FT FRI AND FRI NIGHT. HEADLINES MAY BE REQUIRED
FOR THE SECOND HALF OF THE PERIOD.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 AM WEDNESDAY...BERMUDA HIGH COMBINED WITH LOW PRESSURE
ROTATING THROUGH THE MID ATLANTIC AND THE APPROACH OF THE
ASSOCIATED COLD FRONT WILL PINCH THE SURFACE GRADIENT SAT INTO
SUN. SOUTHWEST FLOW WILL REMAIN 15 TO 20 KT THOUGH THE PERIOD.
FRONT IS NOT EXPECTED TO MOVE OVER THE WATERS BUT INSTEAD REMAIN
STALLED INLAND. THIS WILL KEEP WINDS OUT OF THE SOUTHWEST THROUGH
SUN. SEAS WILL RUN 3 TO 5 FT BUT GIVEN THE EXTENDED PERIOD OF
WINDS AROUND 20 KT CANNOT RULE OUT SOME 6 FT SEAS...ESPECIALLY
WATERS NEAR 20 NM OPEN TO SOUTHWEST FETCH AND HEADLINES COULD BE
REQUIRED FOR AT LEAST A PORTION OF THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR SCZ017-023-024-
032-033-039-053>056.
HEAT ADVISORY FROM 10 AM TO 8 PM EDT THURSDAY FOR SCZ017-023-
024-032-033-039-053>056.
NC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NCZ087-096-099-
105>110.
HEAT ADVISORY FROM 10 AM TO 8 PM EDT THURSDAY FOR NCZ087-096-
099-105>110.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...III
LONG TERM...III
AVIATION...RGZ/MRR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
130 PM EDT WED JUN 24 2015
.SYNOPSIS...
HOT AND HUMID CONDITIONS WILL PERSIST THROUGH THE END OF THE WEEK
WITH ISOLATED SHOWERS AND THUNDERSTORMS PRIMARILY EACH AFTERNOON AND
EVENING. COOLER TEMPERATURES ALONG WITH A BETTER CHANCE OF SHOWERS
AND THUNDERSTORMS WILL DEVELOP THIS WEEKEND. A DRYING TREND WILL
BEGIN NEXT WEEK AS FRONT STALLED IN THE AREA DISSIPATES AND HIGH
PRESSURE RETURNS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 10 AM WEDNESDAY...A HEAT ADVISORY REMAINS IN EFFECT THROUGH
EARLY THIS EVENING AS TEMPS SOAR INTO AND THROUGH THE 90S ONCE AGAIN
AND COMBINE WITH A VERY HUMID AIR MASS TO CREATE DANGEROUS HEAT.
A COLD FRONT EXTENDING FROM THE MOUNTAINS OF WESTERN NC E-NE TOWARD
NC/VA COAST THIS MORNING WILL PUSH ONLY SLOWLY SOUTH AS IT WASHES
OUT. THIS WILL HELP TO ADVECT SLIGHTLY DRIER AIR IN FROM THE N-NW
AND WILL CREATE A TIGHTER GRADIENT FLOW PRODUCING ENHANCED LOW LEVEL
CONVERGENCE ALONG TROUGH AHEAD OF IT. OVERALL IT WILL JUST PRODUCE A
WIND SHIFT TO A MORE N-NE DIRECTION BEHIND IT AS IT REACHES DOWN
ALONG THE NC/SC BORDER CUTTING ACROSS OUR LOCAL FORECAST AREA THIS
AFTERNOON. THE MUCH LOWER DEWPOINT AIR WILL REMAIN WELL TO THE NORTH
AS SW FLOW AT THE SURFACE CONTINUES TO KEEP A MOISTURE RICH AIR MASS
OVER MUCH OF LOCAL FORECAST AREA....WITH DEWPOINT TEMPS INTO THE 70S
THIS MORNING AND PCP WATER VALUES NEAR 2 INCHES. ML CAPE VALUES WERE
REACHING CLOSE TO 4000 J/KG WITH LI VALUES TO -11. THIS UNSTABLE
ENVIRONMENT WILL INCREASE THE POTENTIAL FOR CONVECTIVE DEVELOPMENT
THIS AFTERNOON. OVERALL THE FORCING WILL BE SHALLOW WITH STEEP LOW
LEVEL LAPSE RATES TO INITIATE STORM DEVELOPMENT THIS AFTERNOON.
THE FOCUS OF CONVECTION WILL BE ALONG THIS SFC BOUNDARY AS IT SHIFTS
SLIGHTLY SOUTH THROUGH THIS AFTERNOON AND COMBINES WITH ENHANCED
CONVERGENCE ALONG SEA BREEZE BOUNDARY AS IT ADVANCES INLAND AND
OTHER LOCALIZED BOUNDARIES. WITH ALL THIS BEING SAID...THERE IS NOT
MUCH IN THE WAY OF UPPER LEVEL SUPPORT AS WE REMAIN ON THE TOP OF
RIDGE ALOFT. THE SW FLOW FROM THE SFC THROUGH THE LOW LEVEL FLOW
WILL VEER TO BECOME MORE WESTERLY WHICH WILL AID IN DOWNSLOPE FLOW
AND HEATING...SOME DRYING AND WILL ALSO HELP TO KEEP SEA BREEZE
PINNED CLOSER TO THE COAST INITIALLY. AS HEATING INCREASES EXPECT CU
AND SHWRS/TSTMS TO FORM ALONG CONVERGENT BOUNDARIES. SPC HAS KEPT
OUR AREA IN A MARGINAL RISK FOR SVR STORMS AS A MODERATELY UNSTABLE
AIR MASS YIELDS STRONG UPDRAFT/DOWNDRAFT GROWTH WITH POTENTIAL FOR
ISOLATED DAMAGING WINDS. THE HRRR SHOWS MAIN FOCUS ALONG WEAKENING
FRONT FROM MARLBORO TO PENDER COUNTIES BY 18Z AND OTHER MORE
ISOLATED CONVECTIVE DEVELOPMENT ALONG SEA BREEZE FROM GEORGETOWN
COUNTY UP THROUGH THE GRAND STRAND INTO THE CAPE FEAR AREA. THE
STEERING FLOW WILL BE OUT OF THE NW WHICH WILL PUSH ALL STORMS
SOUTHEAST AND TOWARD THE COAST WITH OTHER STORMS DEVELOPING ALONG
COLLIDING BOUNDARIES.
MOST OF THIS ACTIVITY WILL END THIS EVENING AS CONVECTION WILL BE
ALMOST EXCLUSIVELY DIURNALLY FORCED. MIN TEMPS TONIGHT WILL AGAIN BE
QUITE WARM...DROPPING ONLY TO AROUND 80 AT THE BEACHES...75 WELL
INLAND.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 130 PM WEDNESDAY...HOT/HUMID SOUTHWESTERLY FLOW WILL CONTINUE
THURSDAY AND FRIDAY NIGHT WHILE MID/UPPER RIDGE MAINTAINS ITS
PRESENCE FOR A COUPLE MORE DAYS. THE HEAT INDEX IS PROJECTED TO
SURPASS HEAT ADVISORY CRITERIA THURSDAY AND WILL LIKELY DO SO AGAIN
ON FRIDAY. THE SOUTHWESTERLY FLOW WILL ALSO SUPPORT ABOVE NORMAL MIN
TEMPERATURES EACH NIGHT WITH LOWS IN THE MID TO UPPER 70S. HIGHS
EACH DAY ARE EXPECTED TO RANGE FROM THE LOWER 90S AT THE COAST TO
THE UPPER 90S TO AROUND 100. ALTHOUGH THE BETTER CHANCES FOR
SHOWERS/TSTMS EXISTS IN THE EXTENDED A CHANCE EXISTS PRIMARILY FOR
EACH AFTERNOON AND EVENING WITH THE SEA BREEZE AS A TRIGGER. PLENTY
OF INSTABILITY EXISTS SO ANY STORM THAT DOES FIRE COULD BE STRONG.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 130 PM WEDNESDAY...A LONG WAVE TROUGH WILL DEVELOP OVER THE
GREAT LAKES BY SATURDAY AND BRING SOME RELIEF FROM THE EXTENDED HEAT
WAVE OF THE LAST COUPLE OF WEEKS. SOUTHWEST FLOW EAST OF THE TROUGH
AXIS WILL RESULT IN A SURGE OF GULF MOISTURE AND UNSETTLED WEATHER
SATURDAY INTO EARLY SUNDAY. CONVECTION WILL COME TO AN END AS A COLD
FRONT MOVES OFF THE COAST BY SUNDAY MORNING...AND SURFACE HIGH
PRESSURE SHOULD BRING TEMPERATURES DOWN TO AROUND CLIMO FOR MONDAY.
RETURN FLOW WILL SET UP TUESDAY AND CONTINUE WEDNESDAY BUT THE LACK
OF DEEP MOISTURE WILL KEEP CONVECTION SCATTERED AT BEST.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 1730Z...TERMINALS ARE VFR THIS AFTERNOON. WINDS ARE LIGHT AND
VARIABLE AT KFLO/KLBT SSW-W AT THE COASTAL TERMINALS.
THUNDERSTORMS RESULTING IN TEMPO REDUCED FLIGHT CONDITIONS AND GUSTY
WINDS WILL BE THE BIGGEST THREATS TO AVIATION MAINLY THIS AFTERNOON
AND EVENING. MOSTLY ISOLATED THUNDERSTORMS WILL DEVELOP ALONG A WEAK
TROUGH AHEAD OF A WEAK COLD FRONT FROM KLBT TO N OF KILM. BEST
CONFIDENCE OF OCCURRENCE WILL BE AT KILM WITH TROUGH/SEA BREEZE
BOUNDARY INTERACTIONS. SOME OUTFLOW BOUNDARIES COULD BE THROWN OFF
TO THE SOUTH ALLOWING THUNDERSTORMS TO RE-DEVELOP FURTHER S TOWARDS
THE SOUTHERN TERMINALS LATER THIS AFTERNOON AND EVENING...BUT
ACTIVITY SHOULD BE WEAKER AND EVEN ISOLATED.
ACTIVITY DISSIPATES DURING THE EVENING WITH LOSS OF HEATING. WINDS
MAY BE VARIABLE IN THE EVENING/EARLY MORNING WHERE STORMS HAVE
OCCURRED...BUT GENERALLY WILL RECOVER TO LIGHT SW FOR THE OVERNIGHT
WITH VFR CONDITIONS. VFR CONTINUES AFTER SUNRISE WITH LIGHT SW WINDS
CONTINUING.
EXTENDED OUTLOOK...ISOLATED SHOWERS AND STORMS THURSDAY. MODERATE
CONFIDENCE FOR SCATTERED TO NUMEROUS SHOWERS AND STORMS FRIDAY
AFTERNOON THROUGH SUNDAY WITH MVFR/IFR CONDITIONS AND POSSIBLE HEAVY
RAIN.
&&
.MARINE... NEAR TERM /THROUGH TONIGHT/...
AS OF 12 PM WEDNESDAY...WINDS WILL REMAIN OUT OF THE SW 10 TO 15 KTS
BETWEEN ATLANTIC HIGH PRESSURE AND TROUGH INLAND. SEAS WILL BE 2 TO
4 FT WITH THE SW WIND CHOP DOMINATING. WINDS WILL SPIKE UP AND BE
GUSTY THROUGH THIS AFTERNOON AS SEA BREEZE ENHANCES THE FLOW.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 130 PM WEDNESDAY...THE SOUTHWEST PRESSURE GRADIENT WILL
PERSIST BETWEEN INLAND TROUGH OF LOW PRESSURE AND HIGH PRESSURE OFF
THE SOUTHEAST UNITED STATES COAST EACH DAY. THE GRADIENT WILL
TIGHTEN BY THURSDAY AFTERNOON AND BREEZY SOUTHWEST FLOW WILL CARRY
INTO FRIDAY. WAVE GUIDANCE INDICATES THAT A 1-2 FT SOUTHEAST SWELL
WILL REMAIN MASKED BY THE MORE DOMINANT LOWER PERIOD WAVES AS A
RESULT OF THE SOUTHWESTERLY FETCH. THUS NOT THE BEST OF BOATING FOR
THE COASTAL WATERS WITH SOME STEEP CONDITIONS POSSIBLE.
LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 130 PM WEDNESDAY...SOUTHWEST FLOW WILL INCREASE SATURDAY WITH
A TIGHTENING GRADIENT AHEAD OF A COLD FRONT. SMALL CRAFT ADVISORY
CONDITIONS ARE POSSIBLE SATURDAY INTO EARLY SUNDAY AS WINDS SPEEDS
ARE EXPECTED TO REACH 20-25 KTS. THE GRADIENT WILL RELAX WITH THE
APPROACH FROM THE WEST OF THE SURFACE TROUGH AND ASSOCIATED COLD
FRONT. SCATTERED TO NUMEROUS SHOWERS AND TSTMS AHEAD OF THE FRONT
WILL DIMINISH ON SUNDAY...AND WINDS ARE EXPECTED TO SHIFT TO THE
NORTHEAST SUNDAY NIGHT AS HIGH PRESSURE BUILDS OVER THE WATERS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR SCZ017-023-024-
032-033-039-053>056.
HEAT ADVISORY FROM 10 AM TO 8 PM EDT THURSDAY FOR SCZ017-023-
024-032-033-039-053>056.
NC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NCZ087-096-099-
105>110.
HEAT ADVISORY FROM 10 AM TO 8 PM EDT THURSDAY FOR NCZ087-096-
099-105>110.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...SRP
LONG TERM...CRM
AVIATION...MRR/RGZ
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1212 PM EDT WED JUN 24 2015
.SYNOPSIS...
HOT AND HUMID CONDITIONS WILL PERSIST THROUGH THE END OF THE WEEK
WITH ISOLATED SHOWERS AND THUNDERSTORMS PRIMARILY DURING THE
AFTERNOONS AND EVENINGS. MUCH COOLER TEMPERATURES ALONG WITH A
BETTER CHANCE OF SHOWERS AND THUNDERSTORMS WILL DEVELOP THIS
WEEKEND. A DRYING TREND WILL BEGIN NEXT WEEK AS FRONT STALLED IN
THE AREA DISSIPATES AND HIGH PRESSURE RETURNS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM WEDNESDAY...A HEAT ADVISORY REMAINS IN EFFECT
THROUGH EARLY THIS EVENING AS TEMPS SOAR INTO AND THROUGH THE 90S
ONCE AGAIN AND COMBINE WITH A VERY HUMID AIR MASS TO CREATE
DANGEROUS HEAT.
A COLD FRONT EXTENDING FROM THE MOUNTAINS OF WESTERN NC E-NE
TOWARD NC/VA COAST THIS MORNING WILL PUSH ONLY SLOWLY SOUTH AS IT
WASHES OUT. THIS WILL HELP TO ADVECT SLIGHTLY DRIER AIR IN FROM
THE N-NW AND WILL CREATE A TIGHTER GRADIENT FLOW PRODUCING
ENHANCED LOW LEVEL CONVERGENCE ALONG TROUGH AHEAD OF IT. OVERALL
IT WILL JUST PRODUCE A WIND SHIFT TO A MORE N-NE DIRECTION BEHIND
IT AS IT REACHES DOWN ALONG THE NC/SC BORDER CUTTING ACROSS OUR
LOCAL FORECAST AREA THIS AFTERNOON. THE MUCH LOWER DEWPOINT AIR
WILL REMAIN WELL TO THE NORTH AS SW FLOW AT THE SURFACE CONTINUES
TO KEEP A MOISTURE RICH AIR MASS OVER MUCH OF LOCAL FORECAST
AREA....WITH DEWPOINT TEMPS INTO THE 70S THIS MORNING AND PCP
WATER VALUES NEAR 2 INCHES. ML CAPE VALUES WERE REACHING CLOSE TO
4000 J/KG WITH LI VALUES TO -11. THIS UNSTABLE ENVIRONMENT WILL
INCREASE THE POTENTIAL FOR CONVECTIVE DEVELOPMENT THIS AFTERNOON.
OVERALL THE FORCING WILL BE SHALLOW WITH STEEP LOW LEVEL LAPSE
RATES TO INITIATE STORM DEVELOPMENT THIS AFTERNOON.
THE FOCUS OF CONVECTION WILL BE ALONG THIS SFC BOUNDARY AS IT
SHIFTS SLIGHTLY SOUTH THROUGH THIS AFTERNOON AND COMBINES WITH
ENHANCED CONVERGENCE ALONG SEA BREEZE BOUNDARY AS IT ADVANCES
INLAND AND OTHER LOCALIZED BOUNDARIES. WITH ALL THIS BEING
SAID...THERE IS NOT MUCH IN THE WAY OF UPPER LEVEL SUPPORT AS WE
REMAIN ON THE TOP OF RIDGE ALOFT. THE SW FLOW FROM THE SFC THROUGH
THE LOW LEVEL FLOW WILL VEER TO BECOME MORE WESTERLY WHICH WILL
AID IN DOWNSLOPE FLOW AND HEATING...SOME DRYING AND WILL ALSO HELP
TO KEEP SEA BREEZE PINNED CLOSER TO THE COAST INITIALLY. AS
HEATING INCREASES EXPECT CU AND SHWRS/TSTMS TO FORM ALONG
CONVERGENT BOUNDARIES. SPC HAS KEPT OUR AREA IN A MARGINAL RISK
FOR SVR STORMS AS A MODERATELY UNSTABLE AIR MASS YIELDS STRONG
UPDRAFT/DOWNDRAFT GROWTH WITH POTENTIAL FOR ISOLATED DAMAGING
WINDS. THE HRRR SHOWS MAIN FOCUS ALONG WEAKENING FRONT FROM
MARLBORO TO PENDER COUNTIES BY 18Z AND OTHER MORE ISOLATED
CONVECTIVE DEVELOPMENT ALONG SEA BREEZE FROM GEORGETOWN COUNTY UP
THROUGH THE GRAND STRAND INTO THE CAPE FEAR AREA. THE STEERING
FLOW WILL BE OUT OF THE NW WHICH WILL PUSH ALL STORMS SOUTHEAST
AND TOWARD THE COAST WITH OTHER STORMS DEVELOPING ALONG COLLIDING
BOUNDARIES.
MOST OF THIS ACTIVITY WILL END THIS EVENING AS CONVECTION WILL BE
ALMOST EXCLUSIVELY DIURNALLY FORCED. MIN TEMPS TONIGHT WILL AGAIN
BE QUITE WARM...DROPPING ONLY TO AROUND 80 AT THE BEACHES...75
WELL INLAND.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...LONG LIVED MID LEVEL RIDGE WILL START SHOWING
SIGNS OF WEAKENING DURING THE PERIOD ALTHOUGH THE HEAT AND HUMIDITY
WILL CONTINUE. RIDGE HOLDS ON THU BUT STARTS TO BREAK DOWN LATER FRI
AS 5H TROUGH APPROACHES FROM THE NORTHWEST. AT THE SURFACE THE
BERMUDA HIGH AND PIEDMONT TROUGH REMAIN IN PLACE ALONG WITH DAILY
DEVELOPMENT OF THE AFTERNOON SEA BREEZE. DEEP MOISTURE REMAINS IN
PLACE WITH PRECIPITABLE WATER VALUES RUNNING BETWEEN 1.75 AND 2
INCHES. MID LEVEL LAPSE RATES ARE STEEP ENOUGH FOR DEVELOPMENT OF
MODERATE TO STRONG UPDRAFTS WITH ONLY A SHALLOW LAYER OF LESS
FAVORABLE LAPSE RATES TO OVERCOME. THE PROBLEM IS THE HEIGHT OF THIS
SHALLOW STABLE LAYER WHICH IS BASED BETWEEN 7K AND 8K FT. THIS MAY
BE TOO HIGH FOR THE SEA BREEZE AND PIEDMONT TROUGH TO OVERCOME ON
THEIR OWN. ATMOSPHERE MAY REQUIRE SOME BOUNDARY INTERACTION...WITH
LEFT OVER CONVECTIVE BOUNDARIES...AND HEATING BEFORE DEEPER
CONVECTION IS ABLE TO DEVELOP. WILL CARRY CHC POP EACH AFTERNOON BUT
FAVOR A LATER TIMING GIVEN THE AFOREMENTIONED LIMITATIONS.
TEMPERATURES WILL CONTINUE TO RUN WELL ABOVE CLIMO WITH HIGHS IN THE
MID 90S AND LOWS IN THE MID TO UPPER 70S.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...MID LEVEL TROUGH AND STALLED SURFACE BOUNDARY
WILL RESULT IN UNSETTLED WEATHER FOR MUCH OF THE PERIOD. LARGE 5H
TROUGH SETS UP OVER THE EASTERN CONUS BUT THE TROUGHS AXIS WILL
REMAIN WEST OF THE AREA THROUGH TUE. COMBINATION OF DIURNAL
HEATING...DEEP AND MOIST SOUTHWEST FLOW...AND AN OCCASIONAL
SHORTWAVE ROTATING AROUND THE BASE OF THE TROUGH WILL LEAD TO AN
INCREASE IN SHOWER AND THUNDERSTORM ACTIVITY ACROSS THE AREA. BEST
CHANCES WILL BE SAT INTO SUN AS THE TROUGH ARRIVES AND PUSHES A COLD
FRONT INTO THE AREA. DEEP MOISTURE PRESENT AHEAD OF THE TROUGH ALONG
WITH SHORTWAVE ENERGY WARRANTS AT LEAST HIGH CHC TO LIKELY POP SAT.
MOISTURE LINGERS THROUGH THE FIRST HALF OF SUN BUT LOW LEVEL
INSTABILITY DECREASES. WILL HOLD ONTO PRECIP CHANCES SUN AND SUN
NIGHT BUT TREND POP DOWNWARD...ESPECIALLY SUN NIGHT.
MID LEVEL DRY AIR WORKS IN FOR LATE SUN THROUGH TUE AS A LOBE OF THE
5H TROUGH EJECTS NORTHEAST...WITH WEAK SUBSIDENCE OVER THE
SOUTHEAST. LONGWAVE TROUGH AXIS REMAINS WEST OF THE AREA AND THE
DISSIPATING FRONT WILL REMAIN STALLED OVER OR JUST EAST OF THE AREA.
THE LACK OF MID LEVEL MOISTURE WILL HINDER DEEPER CONVECTION BUT
STILL EXPECT AT LEAST SOME DEVELOPMENT. PLAN TO MAINTAIN INHERITED
SILENT POP MON AND TUE GIVEN AN UNFAVORABLE ENVIRONMENT AND A FAIR
AMOUNT OF UNCERTAINTY.
HIGH TEMPERATURES WILL BE NEAR TO SLIGHTLY BELOW CLIMO DUE TO THE
INCREASED MOISTURE/CLOUD COVER ALONG WITH THE POTENTIAL FOR MORE
CONVECTION. LOWS WILL CONTINUE TO RUN ABOVE CLIMO.
&&
.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
AS OF 12Z...TERMINALS ARE VFR THIS MORNING AND VFR WILL LIKELY
CONTINUE THROUGH 18Z. WINDS WILL BE SW-W 5-10 KTS EXCEPT BECOMING
SSW AT THE COASTAL TERMINALS MID MORNING ON.
THUNDERSTORMS RESULTING IN TEMPO REDUCED FLIGHT CONDITIONS AND GUSTY
WINDS WILL BE THE BIGGEST THREATS TO AVIATION MAINLY THIS AFTERNOON
AND EVENING. THUNDERSTORMS SHOULD DEVELOP AFTER 17Z INITIALLY ALONG
A WEAK FRONT NEAR KLBT TO N OF KILM. DRY AIR IN THE MID LEVELS
SHOULD ALLOW FOR LESS ACTIVITY TO DEVELOP ELSEWHERE. SOME BOUNDARIES
COULD THROWN OFF TO THE SOUTH ALLOWING THUNDERSTORMS TO DEVELOP
FURTHER S IN THE AFTERNOON AND EVENING. CONFIDENCE OF THUNDERSTORM
OCCURRENCE IS HIGHEST N.
ACTIVITY DISSIPATES DURING THE EVENING. WINDS MAY BE VARIABLE IN THE
EVENING/EARLY MORNING WHERE STORMS HAVE OCCURRED...BUT GENERALLY
LIGHT SW WINDS CAN BE EXPECTED OVERNIGHT WITH VFR CONDITIONS.
EXTENDED OUTLOOK...ISOLATED SHOWERS AND STORMS THURSDAY. MODERATE
CONFIDENCE FOR SCATTERED TO NUMEROUS SHOWERS AND STORMS FRIDAY
AFTERNOON THROUGH SUNDAY WITH MVFR/IFR CONDITIONS AND POSSIBLE HEAVY
RAIN.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1200 PM WEDNESDAY...WINDS WILL REMAIN OUT OF THE SW 10 TO 15
KTS BETWEEN ATLANTIC HIGH PRESSURE AND TROUGH INLAND. SEAS WILL BE
2 TO 4 FT WITH THE SW WIND CHOP DOMINATING. WINDS WILL SPIKE UP
AND BE GUSTY THROUGH THIS AFTERNOON AS SEA BREEZE ENHANCES THE
FLOW.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...BERMUDA HIGH AND PIEDMONT TROUGH COMBO
WILL MAINTAIN SOUTHWEST FLOW ACROSS THE WATERS THROUGH THE PERIOD.
GRADIENT WILL INCREASE THU INTO FRI WITH SOLID 20 KT DEVELOPING
THU NIGHT AND CONTINUING THROUGH THE END OF THE PERIOD. SEAS 3 TO
4 FT AT THE START OF THE PERIOD WILL BUILD TO 3 TO 5 FT AND
POSSIBLY 4 TO 6 FT FRI AND FRI NIGHT. HEADLINES MAY BE REQUIRED
FOR THE SECOND HALF OF THE PERIOD.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 AM WEDNESDAY...BERMUDA HIGH COMBINED WITH LOW PRESSURE
ROTATING THROUGH THE MID ATLANTIC AND THE APPROACH OF THE
ASSOCIATED COLD FRONT WILL PINCH THE SURFACE GRADIENT SAT INTO
SUN. SOUTHWEST FLOW WILL REMAIN 15 TO 20 KT THOUGH THE PERIOD.
FRONT IS NOT EXPECTED TO MOVE OVER THE WATERS BUT INSTEAD REMAIN
STALLED INLAND. THIS WILL KEEP WINDS OUT OF THE SOUTHWEST THROUGH
SUN. SEAS WILL RUN 3 TO 5 FT BUT GIVEN THE EXTENDED PERIOD OF
WINDS AROUND 20 KT CANNOT RULE OUT SOME 6 FT SEAS...ESPECIALLY
WATERS NEAR 20 NM OPEN TO SOUTHWEST FETCH AND HEADLINES COULD BE
REQUIRED FOR AT LEAST A PORTION OF THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR SCZ017-023-024-
032-033-039-053>056.
NC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NCZ087-096-099-
105>110.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...III
LONG TERM...III
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1137 AM EDT WED JUN 24 2015
.SYNOPSIS...
HOT AND HUMID CONDITIONS WILL PERSIST THROUGH THE END OF THE WEEK
WITH ISOLATED SHOWERS AND THUNDERSTORMS PRIMARILY DURING THE
AFTERNOONS AND EVENINGS. MUCH COOLER TEMPERATURES ALONG WITH A
BETTER CHANCE OF SHOWERS AND THUNDERSTORMS WILL DEVELOP THIS
WEEKEND. A DRYING TREND WILL BEGIN NEXT WEEK AS FRONT STALLED IN
THE AREA DISSIPATES AND HIGH PRESSURE RETURNS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM WEDNESDAY...A HEAT ADVISORY REMAINS IN EFFECT
TODAY AS TEMPS SOAR INTO AND THROUGH THE 90S ONCE AGAIN AND
COMBINE WITH A VERY HUMID AIR MASS TO CREATE DANGEROUS HEAT. A
COLD FRONT EXTENDING FROM THE MOUNTAINS OF WESTERN NC E-NE TOWARD
NC/VA COAST THIS MORNING WILL PUSH ONLY SLOWLY SOUTH AS IT WASHES
OUT. THIS WILL HELP TO ADVECT SLIGHTLY DRIER AIR IN FROM THE N-NW
AND WILL CREATE A TIGHTER GRADIENT FLOW PRODUCING ENHANCED LOW
LEVEL CONVERGENCE ALONG TROUGH AHEAD OF IT. OVERALL IT WILL JUST
PRODUCE A WIND SHIFT TO A MORE N-NE DIRECTION BEHIND IT AS IT
REACHES DOWN ALONG THE NC/SC BORDER CUTTING ACROSS OUR LOCAL
FORECAST AREA THIS AFTERNOON. THE MUCH LOWER DEWPOINT AIR WILL
REMAIN WELL TO THE NORTH AS SW FLOW AT THE SURFACE CONTINUES TO
KEEP A MOISTURE RICH AIR MASS OVER MUCH OF LOCAL FORECAST
AREA....WITH DEWPOINT TEMPS INTO THE 70S THIS MORNING AND PCP
WATER VALUES NEAR 2 INCHES. ML CAPE VALUES WERE REACHING CLOSE TO
4000 J/KG WITH LI VALUES TO -11. THIS UNSTABLE ENVIRONMENT WILL
INCREASE THE POTENTIAL FOR CONVECTIVE DEVELOPMENT THIS AFTERNOON.
OVERALL THE FORCING WILL BE SHALLOW WITH STEEP LOW LEVEL LAPSE
RATES TO INITIATE STORM DEVELOPMENT THIS AFTERNOON. THE FOCUS OF
CONVECTION WILL BE ALONG THIS SFC BOUNDARY AS IT SHIFTS SLIGHTLY
SOUTH THROUGH THIS AFTERNOON AND COMBINES WITH ENHANCED
CONVERGENCE ALONG SEA BREEZE BOUNDARY AS IT ADVANCES INLAND AND
OTHER LOCALIZED BOUNDARIES. WITH ALL THIS BEING SAID...THERE IS
NOT MUCH IN THE WAY OF UPPER LEVEL SUPPORT AS WE REMAIN ON THE TOP
OF RIDGE ALOFT. THE SW FLOW FROM THE SFC THROUGH THE LOW LEVEL
FLOW WILL VEER TO BECOME MORE WESTERLY WHICH WILL AID IN DOWNSLOPE
FLOW AND HEATING...SOME DRYING AND WILL ALSO HELP TO KEEP SEA
BREEZE PINNED CLOSER TO THE COAST INITIALLY. AS HEATING INCREASES
EXPECT CU AND SHWRS/TSTMS TO FORM ALONG CONVERGENT BOUNDARIES. SPC
HAS KEPT OUR AREA IN A MARGINAL RISK FOR SVR STORMS AS A
MODERATELY UNSTABLE AIR MASS YIELDS STRONG UPDRAFT/DOWNDRAFT
GROWTH WITH POTENTIAL FOR ISOLATED DAMAGING WINDS. THE HRRR SHOWS
MAIN FOCUS ALONG WEAKENING FRONT FROM MARLBORO TO PENDER COUNTIES
BY 18Z AND OTHER MORE ISOLATED CONVECTIVE DEVELOPMENT ALONG SEA
BREEZE FROM GEORGETOWN COUNTY UP THROUGH THE GRAND STRAND INTO THE
CAPE FEAR AREA. THE STEERING FLOW WILL BE OUT OF THE NW WHICH WILL
PUSH ALL STORMS SOUTHEAST AND TOWARD THE COAST WITH OTHER STORMS
DEVELOPING ALONG COLLIDING BOUNDARIES.
MOST OF THIS ACTIVITY WILL END THIS EVENING AS CONVECTION WILL BE
ALMOST EXCLUSIVELY DIURNALLY FORCED. MIN TEMPS TONIGHT WILL AGAIN
BE QUITE WARM...DROPPING ONLY TO AROUND 80 AT THE BEACHES...75
WELL INLAND.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...LONG LIVED MID LEVEL RIDGE WILL START SHOWING
SIGNS OF WEAKENING DURING THE PERIOD ALTHOUGH THE HEAT AND HUMIDITY
WILL CONTINUE. RIDGE HOLDS ON THU BUT STARTS TO BREAK DOWN LATER FRI
AS 5H TROUGH APPROACHES FROM THE NORTHWEST. AT THE SURFACE THE
BERMUDA HIGH AND PIEDMONT TROUGH REMAIN IN PLACE ALONG WITH DAILY
DEVELOPMENT OF THE AFTERNOON SEA BREEZE. DEEP MOISTURE REMAINS IN
PLACE WITH PRECIPITABLE WATER VALUES RUNNING BETWEEN 1.75 AND 2
INCHES. MID LEVEL LAPSE RATES ARE STEEP ENOUGH FOR DEVELOPMENT OF
MODERATE TO STRONG UPDRAFTS WITH ONLY A SHALLOW LAYER OF LESS
FAVORABLE LAPSE RATES TO OVERCOME. THE PROBLEM IS THE HEIGHT OF THIS
SHALLOW STABLE LAYER WHICH IS BASED BETWEEN 7K AND 8K FT. THIS MAY
BE TOO HIGH FOR THE SEA BREEZE AND PIEDMONT TROUGH TO OVERCOME ON
THEIR OWN. ATMOSPHERE MAY REQUIRE SOME BOUNDARY INTERACTION...WITH
LEFT OVER CONVECTIVE BOUNDARIES...AND HEATING BEFORE DEEPER
CONVECTION IS ABLE TO DEVELOP. WILL CARRY CHC POP EACH AFTERNOON BUT
FAVOR A LATER TIMING GIVEN THE AFOREMENTIONED LIMITATIONS.
TEMPERATURES WILL CONTINUE TO RUN WELL ABOVE CLIMO WITH HIGHS IN THE
MID 90S AND LOWS IN THE MID TO UPPER 70S.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...MID LEVEL TROUGH AND STALLED SURFACE BOUNDARY
WILL RESULT IN UNSETTLED WEATHER FOR MUCH OF THE PERIOD. LARGE 5H
TROUGH SETS UP OVER THE EASTERN CONUS BUT THE TROUGHS AXIS WILL
REMAIN WEST OF THE AREA THROUGH TUE. COMBINATION OF DIURNAL
HEATING...DEEP AND MOIST SOUTHWEST FLOW...AND AN OCCASIONAL
SHORTWAVE ROTATING AROUND THE BASE OF THE TROUGH WILL LEAD TO AN
INCREASE IN SHOWER AND THUNDERSTORM ACTIVITY ACROSS THE AREA. BEST
CHANCES WILL BE SAT INTO SUN AS THE TROUGH ARRIVES AND PUSHES A COLD
FRONT INTO THE AREA. DEEP MOISTURE PRESENT AHEAD OF THE TROUGH ALONG
WITH SHORTWAVE ENERGY WARRANTS AT LEAST HIGH CHC TO LIKELY POP SAT.
MOISTURE LINGERS THROUGH THE FIRST HALF OF SUN BUT LOW LEVEL
INSTABILITY DECREASES. WILL HOLD ONTO PRECIP CHANCES SUN AND SUN
NIGHT BUT TREND POP DOWNWARD...ESPECIALLY SUN NIGHT.
MID LEVEL DRY AIR WORKS IN FOR LATE SUN THROUGH TUE AS A LOBE OF THE
5H TROUGH EJECTS NORTHEAST...WITH WEAK SUBSIDENCE OVER THE
SOUTHEAST. LONGWAVE TROUGH AXIS REMAINS WEST OF THE AREA AND THE
DISSIPATING FRONT WILL REMAIN STALLED OVER OR JUST EAST OF THE AREA.
THE LACK OF MID LEVEL MOISTURE WILL HINDER DEEPER CONVECTION BUT
STILL EXPECT AT LEAST SOME DEVELOPMENT. PLAN TO MAINTAIN INHERITED
SILENT POP MON AND TUE GIVEN AN UNFAVORABLE ENVIRONMENT AND A FAIR
AMOUNT OF UNCERTAINTY.
HIGH TEMPERATURES WILL BE NEAR TO SLIGHTLY BELOW CLIMO DUE TO THE
INCREASED MOISTURE/CLOUD COVER ALONG WITH THE POTENTIAL FOR MORE
CONVECTION. LOWS WILL CONTINUE TO RUN ABOVE CLIMO.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS OF 12Z...TERMINALS ARE VFR THIS MORNING AND VFR WILL LIKELY
CONTINUE THROUGH 18Z. WINDS WILL BE SW-W 5-10 KTS EXCEPT BECOMING
SSW AT THE COASTAL TERMINALS MID MORNING ON.
THUNDERSTORMS RESULTING IN TEMPO REDUCED FLIGHT CONDITIONS AND GUSTY
WINDS WILL BE THE BIGGEST THREATS TO AVIATION MAINLY THIS AFTERNOON
AND EVENING. THUNDERSTORMS SHOULD DEVELOP AFTER 17Z INITIALLY ALONG
A WEAK FRONT NEAR KLBT TO N OF KILM. DRY AIR IN THE MID LEVELS
SHOULD ALLOW FOR LESS ACTIVITY TO DEVELOP ELSEWHERE. SOME BOUNDARIES
COULD THROWN OFF TO THE SOUTH ALLOWING THUNDERSTORMS TO DEVELOP
FURTHER S IN THE AFTERNOON AND EVENING. CONFIDENCE OF THUNDERSTORM
OCCURRENCE IS HIGHEST N.
ACTIVITY DISSIPATES DURING THE EVENING. WINDS MAY BE VARIABLE IN THE
EVENING/EARLY MORNING WHERE STORMS HAVE OCCURRED...BUT GENERALLY
LIGHT SW WINDS CAN BE EXPECTED OVERNIGHT WITH VFR CONDITIONS.
EXTENDED OUTLOOK...ISOLATED SHOWERS AND STORMS THURSDAY. MODERATE
CONFIDENCE FOR SCATTERED TO NUMEROUS SHOWERS AND STORMS FRIDAY
AFTERNOON THROUGH SUNDAY WITH MVFR/IFR CONDITIONS AND POSSIBLE HEAVY
RAIN.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM WEDNESDAY...A SCEC REMAINS IN EFFECT UNTIL NOON AS
MODERATE SW WINDS CONTINUED. CONDITIONS WILL IMPROVE AS WINDS
DIMINISH.
WINDS AND SEAS WILL EASE THIS AFTN AS THE LLJ WEAKENS AND THE
OVERALL GRADIENT RELAXES A BIT. WINDS WILL REMAIN FROM THE SW
THROUGH TODAY...BUT FALL TO AROUND 15 KTS...AND SEAS WILL DROP IN
TANDEM TO 3-4 FT WITH THE SW WIND CHOP DOMINATING THE SPECTRUM.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...BERMUDA HIGH AND PIEDMONT TROUGH COMBO
WILL MAINTAIN SOUTHWEST FLOW ACROSS THE WATERS THROUGH THE PERIOD.
GRADIENT WILL INCREASE THU INTO FRI WITH SOLID 20 KT DEVELOPING
THU NIGHT AND CONTINUING THROUGH THE END OF THE PERIOD. SEAS 3 TO
4 FT AT THE START OF THE PERIOD WILL BUILD TO 3 TO 5 FT AND
POSSIBLY 4 TO 6 FT FRI AND FRI NIGHT. HEADLINES MAY BE REQUIRED
FOR THE SECOND HALF OF THE PERIOD.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 AM WEDNESDAY...BERMUDA HIGH COMBINED WITH LOW PRESSURE
ROTATING THROUGH THE MID ATLANTIC AND THE APPROACH OF THE
ASSOCIATED COLD FRONT WILL PINCH THE SURFACE GRADIENT SAT INTO
SUN. SOUTHWEST FLOW WILL REMAIN 15 TO 20 KT THOUGH THE PERIOD.
FRONT IS NOT EXPECTED TO MOVE OVER THE WATERS BUT INSTEAD REMAIN
STALLED INLAND. THIS WILL KEEP WINDS OUT OF THE SOUTHWEST THROUGH
SUN. SEAS WILL RUN 3 TO 5 FT BUT GIVEN THE EXTENDED PERIOD OF
WINDS AROUND 20 KT CANNOT RULE OUT SOME 6 FT SEAS...ESPECIALLY
WATERS NEAR 20 NM OPEN TO SOUTHWEST FETCH AND HEADLINES COULD BE
REQUIRED FOR AT LEAST A PORTION OF THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR SCZ017-023-024-
032-033-039-053>056.
NC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NCZ087-096-099-
105>110.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...III
LONG TERM...III
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
107 PM CDT WED JUN 24 2015
.UPDATE...
ISSUED AT 1253 PM CDT WED JUN 24 2015
AS THE FOCUS BEGINS TO SHIFT TO THE NEXT ROUND OF SHOWERS AND
THUNDERSTORMS...TIMING ONCE AGAIN NEEDED ADJUSTMENT ON THE BROKEN
LINE OF SHOWERS AND THUNDERSTORMS MOVING THROUGH THE U.S. 83
CORRIDOR.
UPDATE ISSUED AT 940 AM CDT WED JUN 24 2015
THE LATEST RADAR INDICATES CONVECTION IS MOVING FASTER THAN A
CONSENSUS OF THE LAST THREE HRRR RUNS. PRECIPITATION CHANCES WERE
UPDATED TO DO A BETTER JOB OF INDICATING THE MOST LIKELY TIMES FOR
PRECIPITATION AS A MID LEVEL SHORTWAVE RACES ACROSS THE STATE
TODAY. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS WILL COMMENCE AS
THE NEXT IN A LONG TRAIN OF SHORTWAVES MOVES FROM WESTERN MONTANA
INTO THE DAKOTAS AFTER MIDNIGHT TONIGHT...SO THAT WILL BE THE
SHORT TERM FOCUS FOR LATER FORECAST UPDATES.
UPDATE ISSUED AT 618 AM CDT WED JUN 24 2015
APPROACHING SHORT WAVE IS BRINGING SCATTERED SHOWERS/THUNDERSTORMS
ACROSS EASTERN MONTANA NUDGING INTO NORTHWEST NORTH DAKOTA. HAVE
ADJUSTED POPS A BIT TO ACCOUNT FOR THIS. HAVE ALSO ADJUSTED CLOUD
COVER WITH THE APPROACHING STORMS AND TO ACCOUNT FOR CLOUDS STREAMING
OFF THE ONGOING CONVECTION OVER SOUTHWEST/SOUTH CENTRAL SOUTH
DAKOTA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM CDT WED JUN 24 2015
THUNDERSTORMS ONCE AGAIN HIGHLIGHT THE SHORT TERM.
WITH PERSISTENT ZONAL FLOW AND UPPER LEVEL JET PARKED OVER THE
REGION...AND LEE CYCLOGENESIS...DIURNAL THUNDERSTORMS WILL
CONTINUE TO BE POSSIBLE. SHORT TERM MODELS INDICATE THUNDERSTORM
DEVELOPMENT ACROSS EASTERN MONTANA AND WESTERN NORTH DAKOTA LATE
THIS MORNING INTO THE EARLY AFTERNOON HOURS...SPREADING ACROSS
CENTRAL NORTH DAKOTA LATE IN THE AFTERNOON AND EVENING HOURS. A
MOIST AND UNSTABLE BOUNDARY LAYER REMAINS ACROSS THE NORTHERN
PLAINS. WITH SOUTHERLY FLOW AT THE SURFACE AND STRONG WESTERLIES
ALOFT...SHEAR WILL CONTINUE TO BE VERY STRONG. SPC HAS NORTH
DAKOTA IN A MARGINAL RISK FOR SEVERE STORMS TODAY. WITH PERSISTENT
CAPE GREATER THAN 1K J/KG AND SHEAR GREATER THAN 50 KNOTS...ANY
STORMS THAT DO FORM COULD QUICKLY BECOME SUPERCELLULAR WITH THE
THREAT FOR DAMAGING WIND AND HAIL.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 333 AM CDT WED JUN 24 2015
HIGHLIGHT IN THE LONG TERM WILL BE DIMINISHING THUNDERSTORM
CHANCES GOING INTO THE WEEKEND ALONG WITH A WARMING TREND.
WEST/NORTHWEST FLOW CONTINUES ON THURSDAY WHILE UPPER RIDGE OVER
THE WESTERN CONUS STARTS TO GRADUALLY INTENSIFY. VARIETY OF WEAK
DISTURBANCES CONTINUE TO MOVE THROUGH THE FLOW BRINGING
THUNDERSTORM CHANCES. MODEST SHEAR/INSTABILITY OVER MOST OF THE
AREA WILL KEEP SEVERE THREAT ON THE LOW SIDE...THOUGH OVER THE
SOUTHWEST 0-6 KM BULK SHEAR WILL APPROACH 40KTS WITH CAPE VALUES
~1-1.5 KJ/KG WILL BRING A MARGINAL SEVERE THREAT.
FOR FRIDAY RIDGE CONTINUES TO AMPLIFY WITH UPPER FLOW SHIFTING
MORE NORTHWESTERLY...THOUGH A FEW WEAK WAVES MOVING THROUGH MAY
BRING A FEW THUNDERSTORMS TO THE AREA.
FOR THE WEEKEND...RIDGE CONTINUES TO AMPLIFY. THIS WILL BRING DRY
CONDITIONS OVER OUR WEST...WITH POSSIBLY A FEW STORMS TOWARDS THE
EAST AS A FEW WEAK WAVES MOVE THROUGH. TEMPERATURES WILL WARM TO
ABOVE AVERAGE.
WARM TEMPERATURES CONTINUE INTO EARLY NEXT WEEK WITH OCCASIONAL
LOW THUNDERSTORMS CHANCES AS A FEW WEAK WAVES MOVE THROUGH
NORTHWESTERLY UPPER LEVEL FLOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1253 PM CDT WED JUN 24 2015
A BROKEN LINE OF CONVECTION STRETCHING FROM KMOT TO KBIS WILL
PROGRESS EAST TO KJMS TODAY. A SECOND ROUND OF SHOWERS AND
THUNDERSTORMS ARE FORECAST FOR TONIGHT...WITH LOW CONFIDENCE ON
TIMING IN TAFS INDICATED BY VCTS AT KBIS/KISN/KDIK.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SCHECK
SHORT TERM...AJ
LONG TERM...JJS
AVIATION...SCHECK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
956 AM CDT WED JUN 24 2015
.UPDATE...
ISSUED AT 940 AM CDT WED JUN 24 2015
THE LATEST RADAR INDICATES CONVECTION IS MOVING FASTER THAN A
CONSENSUS OF THE LAST THREE HRRR RUNS. PRECIPITATION CHANCES WERE
UPDATED TO DO A BETTER JOB OF INDICATING THE MOST LIKELY TIMES FOR
PRECIPITATION AS A MID LEVEL SHORTWAVE RACES ACROSS THE STATE
TODAY. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS WILL COMMENCE AS
THE NEXT IN A LONG TRAIN OF SHORTWAVES MOVES FROM WESTERN MONTANA
INTO THE DAKOTAS AFTER MIDNIGHT TONIGHT...SO THAT WILL BE THE
SHORT TERM FOCUS FOR LATER FORECAST UPDATES.
UPDATE ISSUED AT 618 AM CDT WED JUN 24 2015
APPROACHING SHORT WAVE IS BRINGING SCATTERED SHOWERS/THUNDERSTORMS
ACROSS EASTERN MONTANA NUDGING INTO NORTHWEST NORTH DAKOTA. HAVE
ADJUSTED POPS A BIT TO ACCOUNT FOR THIS. HAVE ALSO ADJUSTED CLOUD
COVER WITH THE APPROACHING STORMS AND TO ACCOUNT FOR CLOUDS STREAMING
OFF THE ONGOING CONVECTION OVER SOUTHWEST/SOUTH CENTRAL SOUTH
DAKOTA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM CDT WED JUN 24 2015
THUNDERSTORMS ONCE AGAIN HIGHLIGHT THE SHORT TERM.
WITH PERSISTENT ZONAL FLOW AND UPPER LEVEL JET PARKED OVER THE
REGION...AND LEE CYCLOGENESIS...DIURNAL THUNDERSTORMS WILL
CONTINUE TO BE POSSIBLE. SHORT TERM MODELS INDICATE THUNDERSTORM
DEVELOPMENT ACROSS EASTERN MONTANA AND WESTERN NORTH DAKOTA LATE
THIS MORNING INTO THE EARLY AFTERNOON HOURS...SPREADING ACROSS
CENTRAL NORTH DAKOTA LATE IN THE AFTERNOON AND EVENING HOURS. A
MOIST AND UNSTABLE BOUNDARY LAYER REMAINS ACROSS THE NORTHERN
PLAINS. WITH SOUTHERLY FLOW AT THE SURFACE AND STRONG WESTERLIES
ALOFT...SHEAR WILL CONTINUE TO BE VERY STRONG. SPC HAS NORTH
DAKOTA IN A MARGINAL RISK FOR SEVERE STORMS TODAY. WITH PERSISTENT
CAPE GREATER THAN 1K J/KG AND SHEAR GREATER THAN 50 KNOTS...ANY
STORMS THAT DO FORM COULD QUICKLY BECOME SUPERCELLULAR WITH THE
THREAT FOR DAMAGING WIND AND HAIL.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 333 AM CDT WED JUN 24 2015
HIGHLIGHT IN THE LONG TERM WILL BE DIMINISHING THUNDERSTORM
CHANCES GOING INTO THE WEEKEND ALONG WITH A WARMING TREND.
WEST/NORTHWEST FLOW CONTINUES ON THURSDAY WHILE UPPER RIDGE OVER
THE WESTERN CONUS STARTS TO GRADUALLY INTENSIFY. VARIETY OF WEAK
DISTURBANCES CONTINUE TO MOVE THROUGH THE FLOW BRINGING
THUNDERSTORM CHANCES. MODEST SHEAR/INSTABILITY OVER MOST OF THE
AREA WILL KEEP SEVERE THREAT ON THE LOW SIDE...THOUGH OVER THE
SOUTHWEST 0-6 KM BULK SHEAR WILL APPROACH 40KTS WITH CAPE VALUES
~1-1.5 KJ/KG WILL BRING A MARGINAL SEVERE THREAT.
FOR FRIDAY RIDGE CONTINUES TO AMPLIFY WITH UPPER FLOW SHIFTING
MORE NORTHWESTERLY...THOUGH A FEW WEAK WAVES MOVING THROUGH MAY
BRING A FEW THUNDERSTORMS TO THE AREA.
FOR THE WEEKEND...RIDGE CONTINUES TO AMPLIFY. THIS WILL BRING DRY
CONDITIONS OVER OUR WEST...WITH POSSIBLY A FEW STORMS TOWARDS THE
EAST AS A FEW WEAK WAVES MOVE THROUGH. TEMPERATURES WILL WARM TO
ABOVE AVERAGE.
WARM TEMPERATURES CONTINUE INTO EARLY NEXT WEEK WITH OCCASIONAL
LOW THUNDERSTORMS CHANCES AS A FEW WEAK WAVES MOVE THROUGH
NORTHWESTERLY UPPER LEVEL FLOW.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 618 AM CDT WED JUN 24 2015
ISOLD/SCT TSRA EXPECTED THROUGH TODAY INTO TONIGHT ACROSS WESTERN
AND CENTRAL NORTH DAKOTA. OTHERWISE...VFR CONDITIONS WILL PREVAIL.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SCHECK
SHORT TERM...AJ
LONG TERM...JJS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1220 AM CDT WED JUN 24 2015
.UPDATE...
ISSUED AT 1216 AM CDT WED JUN 24 2015
NO MAJOR CHANGES WITH THIS UPDATE. THUNDERSTORMS CONTINUE TO
DIMINISH EARLY THIS MORNING. ANOTHER ROUND OF THUNDERSTORMS IS
EXPECTED LATER THIS MORNING ACROSS EASTERN MONTANA AND WESTERN
NORTH DAKOTA.
UPDATE ISSUED AT 937 PM CDT TUE JUN 23 2015
THE CHALLENGE FOR THE REMAINDER OF THE NIGHT IS THE COVERAGE AND
INTENSITY OF CONVECTION LATE TONIGHT ACROSS WESTERN AND CENTRAL
NORTH DAKOTA FROM THUNDERSTORM ACTIVITY THAT WILL PROPAGATE EAST
FROM CENTRAL AND EASTERN MONTANA. THE 01 UTC RAP DEPICTS MULTIPLE
IMPULSES EVIDENCED BY ONGOING CONVECTION ACROSS MONTANA
PROPAGATING INTO NORTH DAKOTA TONIGHT. 850 MB CAPE VALUES ARE IN
THE 500-800 J/KG RANGE WITH STRONG DEEP LAYER SHEAR WITH THE FAST
WESTERLIES ALOFT. THUS...SMALL HAIL APPEARS TO BE THE LIKELY
THREAT WITH SCATTERED CONVECTION SUSTAINED BY A STRENGTHENING LOW
LEVEL JET AND WARM AIR ADVECTION INTO NORTH DAKOTA.
UPDATE ISSUED AT 543 PM CDT TUE JUN 23 2015
THE 19-21 UTC HRRR ITERATIONS HAVE A GOOD HANDLE ON THE ONGOING
CONVECTION ACROSS WESTERN NORTH DAKOTA...AND WILL USE A BLEND OF
THEIR SOLUTIONS FOR SKY COVER AND POPS THROUGH THE EVENING AND
OVERNIGHT.
A MARGINAL THREAT FOR LARGE HAIL AND DAMAGING WINDS WILL CONTINUE
ACROSS SOUTHWEST AND POSSIBLY INTO SOUTH CENTRAL NORTH DAKOTA
THROUGH SUNSET. THE 22 UTC RAP ANALYSIS DEPICTS STRONG DEEP LAYER
SHEAR OF 40 KTS...WITH ML CAPE VALUES AROUND 1000-1500 J/KG...400
J/KG OF HAIL CAPE AND DOWNDRAFT CAPE AROUND 1000 J/KG.
OVERALL...DEEPER MOISTURE APPEARS TO BE A MITIGATING FACTOR FOR
GREATER STORM INTENSITY. MULTIPLE FUNNEL CLOUD REPORTS HAVE ALSO
BEEN RECEIVED ACROSS THE SOUTHWEST GIVEN THE AT TIMES SUPERCELLUR
NATURE OF THE STORMS. HOWEVER...LOW LEVEL KINEMATIC FIELDS ARE NOT
OVERLY SUPPORTIVE OF TORNADOES.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 129 PM CDT TUE JUN 23 2015
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE CHANCES FOR
THUNDERSTORMS THROUGH THE PERIOD...SOME MARGINALLY SEVERE SOUTHWEST
THIS AFTERNOON/EVENING...AND ACROSS WESTERN AND CENTRAL NORTH DAKOTA
WEDNESDAY.
CURRENTLY...ACTIVE WEST-NORTHWEST FLOW ALOFT WITH A SFC TROUGH
STATIONARY ACROSS THE NORTHERN HIGH PLAINS OF MT/WY. UPPER LEVEL
DIVERGENCE IN THE EXIT REGION OF AN UPPER LEVEL JET COUPLED WITH
DIURNAL INSTABILITY WILL SEE THE CHANCE FOR SHOWERS AND
THUNDERSTORMS THIS AFTERNOON WEST AND NORTH...THEN SPREADING SLOWLY
SOUTHEAST TONIGHT. BEST CHANCE FOR STRONGER STORMS REMAINS ACROSS
THE WESTERN THIRD OF THE STATE...MORE SO THE SOUTHWEST WHERE MODELS
PORTRAY 800-1200 J/KG OF MUCAPE ALONG WITH 50KTS OF 0-6KM SHEAR.
LATEST HRRR ALONG WITH THE 00Z 4KM NSSL WRF INDICATE CONVECTIVE
DEVELOPMENT EARLY TO MID AFTERNOON FROM EASTERN MONTANA INTO
SOUTHWEST AND WEST CENTRAL NORTH DAKOTA. WILL MAINTAIN HIGH CHANCE
SCATTERED POPS FOR THIS AREA.
FOR WEDNESDAY...FLOW ALOFT AND UPPER DIVERGENCE REMAINS UNCHANGED
OVER THE NORTHERN PLAINS. SFC TROUGH ADVANCES EAST WED MORNING AND
AFTERNOON INTO THE CENTRAL DAKOTAS. DAYTIME INSTABILITY AND BULK
SHEAR INDICATE CHANCE FOR THUNDERSTORMS AREA WIDE...MARGINALLY
SEVERE OVER THE ENTIRE COUNTY WARNING AREA (ALL OF WEST AND CENTRAL
ND). WILL MAINTAIN POSSIBLE SEVERE WORDING IN THE HWO. DUE TO THE
UNCERTAINTY...OPTED TO NOT INCLUDE IN THE GRIDS AT THIS TIME.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 129 PM CDT TUE JUN 23 2015
CHANCES FOR SHOWERS AND THUNDERSTORMS ARE EXPECTED TO PERSIST INTO
WEDNESDAY NIGHT...AS AN UPPER LEVEL SHORTWAVE TROUGH CONTINUES ON AN
EASTWARD TRACK OUT OF THE STATE.
A TRANSITION FROM QUASI ZONAL FLOW ALOFT INTO NORTHWEST FLOW IS
EXPECTED THROUGH THURSDAY. THE CURRENT MODEL PACKAGE PROVIDES GOOD
AGREEMENT ON NORTH/NORTHWEST FLOW ALOFT REMAINING IN PLACE THROUGH
THE REST OF THE EXTENDED. SEVERAL EMBEDDED MID-LEVEL SHORTWAVES ARE
PROJECTED ACROSS THE AREA...RESULTING IN FREQUENT CHANCES FOR
ISOLATED/SCATTERED THUNDERSTORMS THOUGH PREDICTABILITY IS LOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1216 AM CDT WED JUN 24 2015
VFR CONDITIONS EXPECTED AT ALL TAF SITES THROUGH THE PERIOD.
THUNDERSTORMS ARE ONCE AGAIN POSSIBLE BEGINNING LATE THIS MORNING
AND EARLY THIS AFTERNOON ACROSS WESTERN NORTH DAKOTA AND
SPREADING EAST THROUGH THE EVENING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AJ
SHORT TERM...NH
LONG TERM...AC
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
658 PM EDT WED JUN 24 2015
.SYNOPSIS...
HIGH PRESSURE OVER THE AREA WILL MOVE EAST INTO PENNSYLVANIA BY
MORNING. LOW PRESSURE WILL MOVE SLOWLY EAST ACROSS OHIO BY
THURSDAY EVENING AND SOUTHEAST OF THE AREA BY FRIDAY. ANOTHER WAVE
OF LOW PRESSURE WILL FORM ALONG A STALLED FRONT OVER THE LOWER
OHIO VALLEY ON FRIDAY AND TRACK INTO PENNSYLVANIA ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
A FAIRLY THICK CIRRUS DECK HAS OVERSPREAD THE AREA AND RAISED
CLOUD COVER IN THE FORECAST THROUGH THE EVENING. CLOUDS WILL
THIN SOME LATER THIS EVENING AND THEN INCREASE AGAIN OVERNIGHT AS
MID-LEVEL MOISTURE ADVECTION ARRIVES.
ALSO MADE SOME ADJUSTMENTS TO HIGH TEMPERATURES ON THURDSDAY.
ALTHOUGH CAN NOT ENTIRELY RULE OUT THE MORE NORTHERN TRACK OF THE
LOW EXHIBITED BY SOME OF THE HIGH RESOLUTION MODELS...THE 18Z
SUITE CONTINUES TO FAVOR A MORE SOUTHERN TRACK. LOOKS LIKE OUR
SOUTHERN TIER OF COUNTIES HAS A CHANCE OF APPROACHING THE 80
DEGREE MARK BUT THINK IT IS UNLIKELY TO REACH MUCH FARTHER NORTH
SO LOWERED HIGHS...ESPECIALLY FROM TOLEDO TO AKRON GIVEN THE
EXPECTED CLOUD COVER AND PRECIPITATION.
PREVIOUS DISCUSSION...
FAIR WEATHER THIS EVENING WILL END AS CLOUDS AND MOISTURE
INCREASE AFTER MIDNIGHT AS THE NEXT CONVECTIVE SYSTEM APPROACHES
FROM THE WEST. MODEL GUIDANCE IS RATHER CONSISTENT OVERNIGHT IN
BRINGING ABOUT A TENTH OF INCH OF QPF INTO THE TOL AREA BY 12Z AS
THE NOSE OF A LOW LEVEL JET AND ATTENDANT CONVERGENCE INCREASES
TOWARD MORNING. ALL CONVECTION ALLOWING MODELS PRODUCE SIMILAR QPF
AND PROGRESSION OF PRECIPITATION INTO NW OHIO. ELSEWHERE FAIR
WEATHER CLOUDS WILL DISSIPATE BEFORE SUNSET WITH JUST THICKENING
HIGH AND MID CLOUDS. THERE IS A SMALL CHANCE OF SHOWERS TOWARD
MORNING MAINLY WEST OF I-71. HAVE USED MAV MEX GUIDANCE FOR
OVERNIGHT LOW TEMPERATURES.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY NIGHT/...
MORE PRECIPITATION IS EXPECTED IN TWO ROUNDS. ONE ON THURSDAY AND
ANOTHER OVER THE WEEKEND.
FOR THURSDAY THE HIGH RESOLUTION MODELS TRACK THE SURFACE LOW FARTHER
NORTH ACROSS NORTHERN OHIO WHILE THE LARGE SCALE MODELS HAVE IT
FARTHER SOUTH. SPC HAS LIKELY MOVED THE SLIGHT RISK AREA FARTHER
NORTH TO ACKNOWLEDGE THE MORE NORTHERLY TRACK OF THE LOW AND HAS
NOW INCLUDED THE SOUTHERN PORTION OF REGION IN A SLIGHT RISK. WITH
LOW LCL HEIGHTS AND CLOSE PROXIMITY TO THE WARM FRONT WILL NEED TO
BE VERY AWARE OF ANY ROTATING STORMS. FARTHER NORTH MORE RAIN IS
EXPECTED AS THE REGION WILL BE IN THE ENTRANCE REGION OF THE UPPER
JET AS WELL AS IN THE NOSE OF THE LOW LEVEL JET. THIS ISENTROPIC
SETUP SHOULD PROVIDE MOD TO STRONG UPWARD MOTION FOR INCREASING
HUMID AIR. WOULD NOT RULE OUT 1-2 INCHES OF QPF ON ALREADY NEARLY
SATURATED SOIL. WE MAY HAVE MORE WATER/FLOOD ISSUES. WILL HOLD OFF
ON MENTIONING ANY FLOOD HEADLINES FOR NOW.
WITH THE REGION MORE IN THE WARM SECTOR...WILL RAISE MAX
TEMPERATURES AS DEPICTED BY THE DOWNSCALED NAM.
THE LOW WILL TRACK EAST THURSDAY EVENING AND THE ATTENDANT
TRAILING FRONT WILL STALL SOUTH OF THE REGION. WILL ATTEMPT TO
KEEP THE FORECAST DRY FOR FRIDAY BUT CAN NOT RULE OUT A BRIEF
LIGHT SHOWER IN THE SOUTH.
ANOTHER MORE SIGNIFICANT SHORT WAVE WILL PROGRESS ACROSS THE
REGION FRIDAY NIGHT AND DEEPEN AS IT PROGRESSES ACROSS THE REGION
OVER THE WEEKEND. THE SREF/GFS/ECMWF ALL TRACK A RATHER
STRONG/DEEP SURFACE LOW JUST SOUTH AND EAST OF THE CWA. THIS WILL
LIKELY PRODUCE MORE RAIN WHICH MAY BE HEAVY. THE SHOWERS WILL
SPREAD INTO THE REGION AFTER MIDNIGHT FRIDAY NIGHT AND CONTINUE
INTO SUNDAY. EXPECT THE HEAVIEST RAIN OVER THE CENTRAL AND EASTERN
PORTIONS OF THE AREA.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AN UNSEASONABLY STRONG UPPER LOW WILL BE OVERHEAD THE
OHIO VALLEY THIS WEEKEND. ON SUNDAY THIS SYSTEM WILL BE SLOWLY
PULLING AWAY. GFSENS BRINGS H8 TEMPERATURES DOWN BELOW 10C. HIGHS
SUNDAY WILL BE SIGNIFICANTLY BELOW NORMAL...LIKELY NOT GETTING OUT OF
THE 60S ACROSS EASTERN OH/NW PA. WILL LINGER PRECIP CHANCES ACROSS
THE AREA UNTIL THAT SYSTEM FULLY DEPARTS. MONDAY WILL BE IN BETWEEN
SYSTEMS WITH SLIGHT RIDGING. THE NEXT SHORTWAVE OF NOTE WILL ARRIVE
WITH A COLD FRONT FOR TUESDAY...RE-ENFORCING THE EASTERN U.S.
TROUGH. THIS IS LATER THAN PREVIOUS FORECAST...BUT WITH STRONG AND
SLOWER WEEKEND SYSTEM THIS IS EXPECTED. SHOWERS AND THUNDERSTORMS
WILL BE ASSOCIATED WITH THIS FRONT. WEDNESDAY SHOULD BE A FAIR
WEATHER WITH CURRENT TIMING OF ALL OF THESE SYSTEMS.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
A LOW WILL MOVE INTO OHIO BY LATE THU. WIDESPREAD SHRA AND SOME
TSRA ARE EXPECTED TO MOVE INTO TOL AND FDY TOWARD THE END OF THE
NIGHT AND SHOULD REACH CLE AROUND 9 TO 10 AM AND FINALLY YNG AND
MAYBE ERI ABOUT MIDDAY. THE RAP MODEL AND NOW THE HRRR ARE SHOWING
A SLOWER AND FURTHER SOUTHWARD PROGRESSION SO UNCERTAINTY WITH THE
FORECAST IS PRESENT. AREAS OF MVFR WILL LIKELY DEVELOP AFTER A FEW
HOURS OF RAIN AS THE LOWER LEVELS BECOME SATURATED. WINDS SHOULD
STAY LIGHT...GENERALLY UNDER 12 KNOTS THRU THU.
OUTLOOK...NON VFR LIKELY THU NIGHT INTO EARLY FRI IN SHRA THEN NON
VFR MAY LINGER ACROSS EASTERN OH/NW PA THE REST OF FRI. WIDESPREAD
NON VFR RETURNS FOR FRIDAY NIGHT THROUGH SUNDAY IN MORE WIDESPREAD
RAIN.
&&
.MARINE...
FAIR WEATHER AND A QUIET LAKE TONIGHT. AFTER THAT WEATHER
QUITE UNSETTLED. LOW PRESSURE WILL TRACK EAST ACROSS OHIO ON
THURSDAY...BRINGING WINDS AROUND TO THE NORTHEAST ON THE LAKE BY
THURSDAY EVENING. NORTHEAST WINDS WILL CONTINUE THROUGH FRIDAY AS
HIGH PRESSURE REMAINS NEARLY STATIONARY ACROSS THE CENTRAL GREAT
LAKES. SIGNIFICANT CHANGES FOR THE WEEKEND FORECAST WITH A TREND
TOWARD A STRONG LOW MOVING INTO THE OHIO VALLEY FRIDAY NIGHT AND
SLOWLY MOVING UP THE OHIO VALLEY THROUGH THE WEEKEND. THIS WOULD
CONTINUE AND STRENGTHEN THE NORTHEAST FLOW ON THE LAKE FOR SATURDAY.
STILL STRONG BUT MORE NORTHERLY WINDS ARE EXPECTED SUNDAY AS THE LOW
BEGINS TO PULL AWAY. SMALL CRAFT ADVISORIES WILL BE A CERTAINTY. WE
ARE TALKING 20 TO 30 KNOTS FOR A BIG CHUNK OF THE WEEKEND.
CONDITIONS SLOWLY IMPROVE ON MONDAY WITH HIGH PRESSURE CENTERED OVER
THE TN VALLEY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LAPLANTE
NEAR TERM...KEC/LAPLANTE
SHORT TERM...LAPLANTE
LONG TERM...OUDEMAN
AVIATION...ADAMS
MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS NORMAN OK
1029 PM CDT THU JUN 25 2015
.AVIATION...
06Z TAFS... A COLD FRONT WILL MOVE ACROSS THE REGION FRIDAY.
SCATTERED SHOWERS/STORMS WILL ALSO BE POSSIBLE EARLY FRIDAY
MORNING THROUGH FRIDAY EVENING ACROSS THE AREA ALTHOUGH CHANCES
ARE TOO LOW FOR MENTION IN SOME TAFS. VFR/LOW VFR CEILINGS ARE
EXPECTED... HOWEVER... SOME MVFR CEILINGS ARE NOT OUT OF THE
QUESTION AT A FEW LOCATIONS.
&&
.PREV DISCUSSION... /ISSUED 901 PM CDT THU JUN 25 2015/
UPDATE...
INCREASED PRECIPITATION CHANCES IN THE NORTH GIVEN THE ROBUST
STORMS IN KANSAS AND RECENT HRRR SOLUTIONS SHOWING SOME
REDEVELOPMENT OVERNIGHT EVEN IF THESE INITIAL STORMS DO DISSIPATE.
HRRR MAY BE TOO AGGRESSIVE BUT STILL BELIEVE THERE IS ENOUGH
CHANCE TO INCREASE POPS A LITTLE OVERNIGHT. OTHERWISE... FORECAST
APPEARS TO BE IN GOOD SHAPE.
PREV DISCUSSION... /ISSUED 617 PM CDT THU JUN 25 2015/
AVIATION...
0Z TAFS...VFR CEILINGS... POSSIBLY SOME MVFR CEILINGS... THIS TAF
PERIOD. A COLD FRONT WILL MOVE ACROSS THE REGION FRIDAY. SCATTERED
SHOWERS/STORMS WILL BE POSSIBLE FRIDAY... WITH THE BEST CHANCE IN
NORTH CENTRAL AND CENTRAL OK ALONG THE FRONT. SOME OF THE RAIN
COULD OCCUR IN PARTS OF N OK BEFORE 12Z FRI BUT CHANCES TOO LOW
FOR MENTION ATTM.
PREV DISCUSSION... /ISSUED 243 PM CDT THU JUN 25 2015/
DISCUSSION...
HOT WEATHER PATTERN WILL PERSIST THROUGH THE REST OF TODAY...AS
WEAK MID LEVEL RIDGING PREVAILS ACROSS THE REGION WITHIN
SOUTHWESTERLY SFC FLOW. HOWEVER...A PATTERN CHANGE IS ON THE WAY
AS WE HEAD TOWARD THIS WEEKEND.
LATE TONIGHT THROUGH EARLY FRIDAY...A COLD FRONT WILL MOVE FROM
KANSAS INTO NORTHERN OKLAHOMA. A FEW STORMS MAY ACCOMPANY THIS
FRONT...THOUGH NO SEVERE STORMS ARE EXPECTED THROUGH TONIGHT. THE
PRESENCE OF SOUTHWESTERLY WINDS AHEAD OF THE FRONT WILL KEEP
OVERNIGHT LOWS QUITE WARM...WITH TEMPS ONLY BOTTOMING OUT IN THE
LOW TO MID 70S.
THE FRONT WILL CONTINUE TO MOVE SOUTHWARD THROUGH THE DAY ON
FRIDAY...AS A DOMINANT UPPER RIDGE BUILDS ACROSS THE WESTERN U.S.
TEMPERATURES NORTH OF THE BOUNDARY SHOULD GENERALLY BE IN THE
UPPER 80S...WITH LOW TO MID 90S COMMON SOUTH OF THE FRONT.
DIFFLUENT UPPER FLOW WILL OVERSPREAD THE AREA ALONG/SOUTH OF THE
FRONT BY MID TO LATE AFTERNOON...ALLOWING FOR SCATTERED
THUNDERSTORM DEVELOPMENT. GIVEN AMPLE MOISTURE AND
INSTABILITY...AND SOME INCREASE IN MID LEVEL WINDS...SEVERE STORMS
WILL BE POSSIBLE. THE MAIN CONCERNS WILL BE DAMAGING WIND GUSTS
AND LARGE HAIL...THOUGH LOCALLY HEAVY RAINFALL MAY ALSO OCCUR.
STORMS WILL LIKELY MERGE INTO ONE OR MORE SOUTHEASTWARD MOVING
STORM COMPLEXES...MOVING ALONG THE FRONT TOWARD THE RED RIVER AND
INTO NORTH TEXAS OVERNIGHT.
IN THE WAKE OF THE FRONT...THE WEEKEND LOOKS FANTASTIC...WITH
HIGHS IN THE MID TO UPPER 80S TO LOW 90S...AND A DRIER AIRMASS
OVERALL.
THE WESTERN U.S. RIDGE/EAST COAST TROUGH CONFIGURATION LOOKS TO
LINGER INTO MUCH OF NEXT WEEK...WITH SEVERAL PASSING FRONTS AND
ASSOCIATED THUNDERSTORM CHANCES MONDAY THROUGH THE LATTER HALF OF
THE WEEK.
AUSTIN
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 76 90 67 85 / 10 50 40 10
HOBART OK 75 93 67 87 / 20 40 40 10
WICHITA FALLS TX 76 95 70 87 / 10 30 50 10
GAGE OK 72 87 63 87 / 30 30 10 0
PONCA CITY OK 77 88 66 86 / 30 40 20 10
DURANT OK 75 92 69 85 / 0 20 60 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
26/25/25
AREA FORECAST DISCUSSION
NWS NORMAN OK
901 PM CDT THU JUN 25 2015
.UPDATE...
INCREASED PRECIPITATION CHANCES IN THE NORTH GIVEN THE ROBUST
STORMS IN KANSAS AND RECENT HRRR SOLUTIONS SHOWING SOME
REDEVELOPMENT OVERNIGHT EVEN IF THESE INITIAL STORMS DO DISSIPATE.
HRRR MAY BE TOO AGGRESSIVE BUT STILL BELIEVE THERE IS ENOUGH
CHANCE TO INCREASE POPS A LITTLE OVERNIGHT. OTHERWISE... FORECAST
APPEARS TO BE IN GOOD SHAPE.
&&
.PREV DISCUSSION... /ISSUED 617 PM CDT THU JUN 25 2015/
AVIATION...
0Z TAFS...VFR CEILINGS... POSSIBLY SOME MVFR CEILINGS... THIS TAF
PERIOD. A COLD FRONT WILL MOVE ACROSS THE REGION FRIDAY. SCATTERED
SHOWERS/STORMS WILL BE POSSIBLE FRIDAY... WITH THE BEST CHANCE IN
NORTH CENTRAL AND CENTRAL OK ALONG THE FRONT. SOME OF THE RAIN
COULD OCCUR IN PARTS OF N OK BEFORE 12Z FRI BUT CHANCES TOO LOW
FOR MENTION ATTM.
PREV DISCUSSION... /ISSUED 243 PM CDT THU JUN 25 2015/
DISCUSSION...
HOT WEATHER PATTERN WILL PERSIST THROUGH THE REST OF TODAY...AS
WEAK MID LEVEL RIDGING PREVAILS ACROSS THE REGION WITHIN
SOUTHWESTERLY SFC FLOW. HOWEVER...A PATTERN CHANGE IS ON THE WAY
AS WE HEAD TOWARD THIS WEEKEND.
LATE TONIGHT THROUGH EARLY FRIDAY...A COLD FRONT WILL MOVE FROM
KANSAS INTO NORTHERN OKLAHOMA. A FEW STORMS MAY ACCOMPANY THIS
FRONT...THOUGH NO SEVERE STORMS ARE EXPECTED THROUGH TONIGHT. THE
PRESENCE OF SOUTHWESTERLY WINDS AHEAD OF THE FRONT WILL KEEP
OVERNIGHT LOWS QUITE WARM...WITH TEMPS ONLY BOTTOMING OUT IN THE
LOW TO MID 70S.
THE FRONT WILL CONTINUE TO MOVE SOUTHWARD THROUGH THE DAY ON
FRIDAY...AS A DOMINANT UPPER RIDGE BUILDS ACROSS THE WESTERN U.S.
TEMPERATURES NORTH OF THE BOUNDARY SHOULD GENERALLY BE IN THE
UPPER 80S...WITH LOW TO MID 90S COMMON SOUTH OF THE FRONT.
DIFFLUENT UPPER FLOW WILL OVERSPREAD THE AREA ALONG/SOUTH OF THE
FRONT BY MID TO LATE AFTERNOON...ALLOWING FOR SCATTERED
THUNDERSTORM DEVELOPMENT. GIVEN AMPLE MOISTURE AND
INSTABILITY...AND SOME INCREASE IN MID LEVEL WINDS...SEVERE STORMS
WILL BE POSSIBLE. THE MAIN CONCERNS WILL BE DAMAGING WIND GUSTS
AND LARGE HAIL...THOUGH LOCALLY HEAVY RAINFALL MAY ALSO OCCUR.
STORMS WILL LIKELY MERGE INTO ONE OR MORE SOUTHEASTWARD MOVING
STORM COMPLEXES...MOVING ALONG THE FRONT TOWARD THE RED RIVER AND
INTO NORTH TEXAS OVERNIGHT.
IN THE WAKE OF THE FRONT...THE WEEKEND LOOKS FANTASTIC...WITH
HIGHS IN THE MID TO UPPER 80S TO LOW 90S...AND A DRIER AIRMASS
OVERALL.
THE WESTERN U.S. RIDGE/EAST COAST TROUGH CONFIGURATION LOOKS TO
LINGER INTO MUCH OF NEXT WEEK...WITH SEVERAL PASSING FRONTS AND
ASSOCIATED THUNDERSTORM CHANCES MONDAY THROUGH THE LATTER HALF OF
THE WEEK.
AUSTIN
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 76 90 67 85 / 10 50 40 10
HOBART OK 75 93 67 87 / 20 40 40 10
WICHITA FALLS TX 76 95 70 87 / 10 30 50 10
GAGE OK 72 87 63 87 / 30 30 10 0
PONCA CITY OK 77 88 66 86 / 30 40 20 10
DURANT OK 75 92 69 85 / 0 20 60 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
805 PM EDT THU JUN 25 2015
.SYNOPSIS...
STRONG MID LEVEL HIGH PRESSURE WILL DISSIPATE ACROSS THE SOUTHEAST
FRIDAY AS A SIGNIFICANT COLD FRONT APPROACHES THE AREA...ENDING THE
RECENT PERIOD OF ABOVE AVERAGE TEMPS. THE COLD FRONT MOVES THROUGH
SATURDAY BRINGING WIDESPREAD SHOWERS AND THUNDERSTORMS TO THE AREA.
BY SUNDAY THE FRONT WILL HAVE MOVED EAST OF THE REGION LEAVING
BEHIND SLIGHTLY BELOW NORMAL TEMPERATURES AND DRIER AIR ACROSS THE
AREA. A WEAK FRONTAL BOUNDARY WILL APPROACH THE AREA BY MID-WEEK
AND LINGER NEAR THE REGION...INCREASING CHANCES FOR SHOWERS THROUGH
THE END OF NEXT WEEK AND RETURNING TEMPERATURES TO SEASONAL NORMS.
&&
.NEAR TERM /THROUGH FRIDAY/...
730 PM UPDATE...THE CHANCE OF CONVECTION FIRING IN SITU OVER THE
CWFA APPEARS MINIMAL. A COUPLE CLUSTERS OF CELLS OVER ERN KY HAVE
FORMED IN AN AREA WITH SUFFICIENT INSTABILTIY AND SHEAR THAT THEY
LOOKED LIKELY TO ORGANIZE AND PROPAGATE INTO EAST TN...BUT THEY ARE
NOT LOOKING THAT HEALTHY NOW THAT THE SUN IS LOWERING. EARLIER CAM
RUNS SHOWING A WELL DEVELOPED LINEAR MCS OVERNIGHT ARE NOT VERIFYING
WELL SO FAR. THE HRRR IS KEYING ON THE SHEAR...TRYING TO ORGANIZE
ACTIVITY OVER KY OR IL OVER THE NEXT COUPLE HRS...BUT THESE RUNS TOO
SEEM TO BE A BIT OVERDONE. THE CHANCE OF ANY ACTIVITY MOVING ACRS
THE MTNS LOOKS EVEN LESS AT THIS POINT...BUT HAVE KEPT A SCHC NEAR
THE TN/NC BORDER FOR THE SECOND HALF OF THE NIGHT. POPS OVER THE
PIEDMONT WILL DIMINISH STEADILY THRU THE EVENING.
AS OF 230 PM THU...THE AXIS OF A THERMAL SURFACE TROUGH CURRENTLY
EXTENDS THROUGH THE CHARLOTTE METRO AREA INTO THE NC TRIAD. SBCAPE
ALONG THIS AXIS IS QUITE ROBUST...IN EXCESS OF 3000 J/KG PER THE
LATEST SPC MESOANALYSIS. SOME CONGESTUS WAS BEGINNING TO DEVELOP IN
THIS AREA...ALTHOUGH FROM ITS APPEARANCE AND SATELLITE...WE/RE STILL
PROBABLY A GOOD 1-2 HOURS FROM SEEING THE FIRST CELL INITIATE. THERE
ARE STILL DOUBTS AS TO HOW MUCH COVERAGE WILL BE SEEN IN THIS
AREA...AND THE CONSENSUS OF CURRENT CAM MODELS STILL SUGGESTS AREAS
TO OUR EAST WILL BE MORE LIKELY TO SEE CONVECTION. THUS...HELD POPS
IN THE LOW CHANCE RANGE. FARTHER WEST...CONVECTION APPEARS EVEN LESS
LIKELY TO INITIATE ANYTIME SOON. DEWPOINTS WERE MIXING OUT ACROSS
THE MTNS...AND THE CU FIELD THERE IS ATYPICALLY FLAT AND SPARSE.
HELD ON TO A SLIGHT CHANCE POPS ACROSS MOST OF THE REMAINDER OF THE
AREA...WITH A LOW CHANCE IN THE CLIMO-FAVORED INITIATION AREA ACROSS
THE UPPER FRENCH BROAD VALLEY AND VICINITY...BUT EVEN THIS MAY PROVE
TO BE A BIT OF A STRETCH.
ATTENTION THIS EVENING WILL TURN TOWARD THE OHIO VALLEY...WHERE
CONVECTION IS FORECAST TO DEVELOP ALONG A FRONTAL ZONE. SBCAPE IN
THIS REGION HAS INCREASED TO AS MUCH AS 5000 J/KG THIS
AFTERNOON...WHILE BULK SHEAR IS MORE THAN RESPECTABLE FOR LATE JUNE.
SOME OF THE CONVECTION-ALLOWING MODELS AND SHORT TERM GUIDANCE
ORGANIZES CLUSTERS OF CONVECTION FROM THE OHIO VALLEY INTO THE
CENTRAL APPALACHIANS...AND TRIES TO DROP SOME ACTIVITY TOWARD THE
WESTERN CAROLINAS LATER THIS EVENING. JUST DO NOT HAVE MUCH
CONFIDENCE THAT ORGANIZED CONVECTION WILL BE ABLE TO SUSTAIN ITSELF
THIS FAR SOUTHEAST...WHERE SHEAR AND INSTABILITY ARE EXPECTED TO
REMAIN CONSIDERABLY WEAKER. THUS...WILL LIMIT OVERNIGHT POPS TO A
SLIGHT CHANCE ACROSS THE FAR NW ZONES.
FRIDAY WILL BE ANOTHER QUITE UNSTABLE DAY ACROSS THE FORECAST
AREA...WITH TEMPS EXPECTED TO SOAR INTO THE 90S ONCE AGAIN. IN TERMS
OF THE CONVECTIVE POTENTIAL...MIXED SIGNALS ABOUND...WITH THE NAM
BLOWING UP A CONSIDERABLE AMOUNT OF CONVECTIVE QPF ACROSS THE AREA
DURING THE AFTERNOON...WHILE THE GFS AND OPERATIONAL CAMS DEPICT
VERY LITTLE IN THE WAY OF CONVECTION OUTSIDE THE MTNS. AS SURFACE
LOW PRESSURE DEVELOPS ACROSS THE OHIO VALLEY LATE IN THE DAY...THERE
COULD BE A PSEUDO-WARM FRONT/SURFACE TROUGH THAT DEVELOPS ACROSS THE
AREA...POSSIBLY PROVIDING AN ADDITIONAL FOCUS FOR CONVECTION. IN
ADDITION...HEIGHT FALLS ARE EXPECTED TO BEGIN OVERSPREADING THE AREA
BY LATE IN THE DAY. THEREFORE...WILL FORECAST 50-60 POPS ACROSS A
MAJORITY OF THE AREA...FAVORING THE EVENING HOURS FOR THE HIGHEST
COVERAGE. SEVERE STORMS WILL BE POSSIBLE...ESPECIALLY IF THE
ATMOSPHERE DOES WAIT THAT LATE IN THE DAY TO RELEASE INSTABILITY...
WHILE HEIGHT FALLS WILL RESULT IN IMPROVING PROFILES...WITH POSSIBLY
AS MUCH AS 25 KTS OF DEEP LAYER SHEAR ANTICIPATED BY EVENING.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY/...
AS OF 210 PM...EXPECT THAT RATHER WIDESPREAD CONVECTION WILL BE
ONGOING AT THE START OF THE PERIOD FRIDAY EVENING AS THE RESULT OF
CONVERGENCE ASSOCIATED WITH A WEAK LOW MOVING NORTHEAST ACROSS THE
SC PIEDMONT IN NC. THE NAM SEEMS TO BE MOST CONSISTENT WITH THIS
FEATURE AND RESULTANT CONVECTION. HENCE...WILL ADVERTISE SCT-
NUMEROUS TYPE POPS FRIDAY EVENING AND SOME OF THESE STORMS COULD BE
SEVERE AS THEY TAP INTO AN AIRMASS WITH CAPES IN EXCESS OF 2000J AND
ENOUGH DRY AIR ALOFT FOR A FEW MICROBURSTS. SOME LOCALLY HEAVY RAIN
IS ALSO POSSIBLE AS PRECIP. WATER INCREASES TO AROUND 2 INCHES OVER
THE PIEDMONT WITH SLOW MOVING STORMS. CONVECTION SHOULD WANE OVER
OUR AREA AS IT MOVES/REDEVLOPS EASTWARD. HENCE...WILL SHOW A
DECREASING TREND IN THE POPS OVERNIGHT BUT SOME SCT
SHOWERS/THUNDERSTORMS MAY PERSIST AS HEIGHTS FALL AS UPPER TROUGH
APPROACHES.
ON SATURDAY...THE 12Z OPERATIONAL MODELS ARE IN AGREEMENT THAT THE
WELL ADVERTISED COLD FRONT IS STILL ON TRACK TO CROSS THE AREA AS AN
UPPER TROUGH DEVELOPS OVER THE EAST. BULK SHEAR IS FORECAST TO
INCREASE INTO THE 30-40 KT RANGE AS THE FRONT APPROACHES. HOWEVER...
ONLY MODEST INSTABILITY IN THE RANGE OF 1000-1500J IS FORECAST. THIS
MAY BE ENOUGH FOR SOME ORGANIZED LINE SEGMENTS TO DEVELOP ALONG AND
AHEAD OF THE COLD FRONT DURING THE SATURDAY. THEREFORE...SOME SCT
DAMAGING WIND EVENTS ARE POSSIBLE MAINLY OUTSIDE THE MOUNTAINS WHERE
THE BEST INSTABILITY WILL EXIST. SPC HAS A LARGE PART OF THE CWA IN
A MARGINAL RISK FOR SEVERE STORMS ON SAT.
THE FRONT AND ASSOCIATED SHOWERS/STORMS WILL MOVE EAST OF THE AREA
SATURDAY EVENING. A MUCH DRYER AND COOLER AIRMASS WILL BEGIN
OVERSPREADING THE AREA SAT NIGHT PRODUCING CLEARING. HIGH PRESSURE
WILL BUILD OVER THE AREA ON SUNDAY PRODUCING PLENTY OF SUNSHINE WITH
PLEASANT TEMPS AND MUCH LOWER HUMIDITY. STAYED CLOSE TO A MODEL
BLEND FOR MOST GRID FIELDS...EXCEPT LEANED ON THE NAM FOR POP TRENDS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
AS OF 300 PM THURSDAY...THE EXTENDED PERIOD BEGINS SUNDAY DRY AND
WITH SLIGHTLY BELOW AVERAGE TEMPERATURES THANKS TO A SIGNIFICANT
COLD FRONTAL PASSAGE. TEMPERATURES REBOUND TO SEASONAL LEVELS
THROUGH THE REMAINDER OF THE WEEK AS THE AREA REMAINS NEAR THE BASE
OF A BROAD MID-LEVEL TROUGH. GUIDANCE BRINGS A WEAKENING FRONT INTO
THE AREA BY MIDWEEK ASSOCIATED WITH A SHORTWAVE TROUGH OVER THE
LOWER GREAT LAKES. THE FRONT WILL STALL INVOF THE TENNESSEE VALLEY
THROUGH THE REMAINDER OF THE WEEK AS WEAK SHORTWAVES RIDE THE BASE
OF THE TROUGH. AS A RESULT...CHANCE POPS EXIST ACROSS THE
AREA BEGINNING TUESDAY AND LASTING THROUGH THE WEEK WITH THE HIGHEST
POPS ACROSS THE MOUNTAINS CLOSER TO THE DIFFUSE FRONTAL BOUNDARY AND
WEAK SHORTWAVE ENERGY.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
AT KCLT...EXPECTING VFR THRU FRI MRNG WITH DRY PROFILES AND WITH
DEWPOINTS HAVING MIXED OUT APPRECIABLY THU AFTN. CYCLONIC UPPER FLOW
WILL SPIN UP A WEAK SFC LOW OVER THE MID-ATLANTIC COAST TONIGHT
WHICH WILL EVENTUALLY VEER WINDS TO NW. THESE WINDS WILL PERSIST
THRU THE MRNG BEFORE STRONGER LOW PRESSURE DEVELOPS OVER THE OHIO
VALLEY AND WINDS RETURN TO SW. HEIGHTS ALOFT GRADUALLY BEGIN TO FALL
FRIDAY WHICH WILL INCREASINGLY SUPPORT CONVECTION THRU THE DAY. BEST
TSRA CHANCE IS LIKELY NEAR THE END OF THE PERIOD...BUT CHC SUPPORTS
PROB30 FROM 18Z ONWARD.
ELSEWHERE...EXPECTING VFR AT ALL TERMINALS INTO FRI MRNG. TSRA NOW
OVER ERN KY MAY PROPAGATE SWD TO NEAR THE TN/NC BORDER LATER
TONIGHT. HOWEVER THE CHC OF ANY PRECIP CROSSING THE MTNS IS QUITE
LOW...THOUGH SOME REMNANT LOW VFR CLOUDS COULD DRIFT OVER KAVL. SOME
OF THE OUTLYING MTN VALLEYS MAY FOG UP OVERNIGHT. DESTABILIZATION
AND TSRA WILL LIKELY BE A BIT LATER THAN NORMAL ON FRIDAY...AS UPPER
DYNAMIC FORCING STRENGTHENS OVER THE AREA...BUT CHC RAMPS UP TO A
MENTIONABLE LEVEL BY MIDDAY. LIGHT NWLY WINDS WILL RETURN OVERNIGHT
OVER NC IN RESPONSE TO LOW PRESSURE DEVELOPING OVER THE
MID-ATLANTIC...WITH THE SC SITES LIKELY REMAINING SW. ALL SITES
RETURN SW BY FRI AFTN AS A STRONGER LOW DEVELOPS TO THE W.
OUTLOOK...A COLD FRONT APPROACHES FROM THE NW FRI NIGHT AND PASSES
SATURDAY. MORNING RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE
POSSIBLE...PARTICULARLY WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND
IN THE MOUNTAIN RIVER VALLEYS. BEHIND THE COLD FRONT...A MUCH DRIER
AND COOLER AIRMASS WILL OVERSPREAD THE REGION FOR EARLY NEXT
WEEK...WITH A SECOND COLD FRONT POSSIBLY ARRIVING BY MID-WEEK.
CONFIDENCE TABLE...
00-06Z 06-12Z 12-18Z 18-00Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 97% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JP
NEAR TERM...JDL/WIMBERLEY
SHORT TERM...LG
LONG TERM...JP
AVIATION...WIMBERLEY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
459 PM EDT WED JUN 24 2015
.SYNOPSIS...
STRONG MID LEVEL HIGH PRESSURE WILL PERSIST ACROSS THE REGION
THROUGH THE REMAINDER OF THE WORK WEEK...MAINTAINING WELL ABOVE
NORMAL TEMPERATURES. A BROAD UPPER LEVEL TROF WILL MOVE OVER THE
REGION OVER THE WEEKEND RETURNING TEMPERATURES TO SEASONAL LEVELS BY
SUNDAY AND INCREASING CHANCES FOR WIDESPREAD SHOWERS AND
THUNDERSTORMS. A COOLER AND DRIER PATTERN WILL TAKE SHAPE AFTER A
FRONT PASSES EARLY IN THE WEEK BEFORE ANOTHER FRONTAL BOUNDARY
APPROACHES THE AREA LATER NEXT WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
445 PM UPDATE...CLUSTERS OF CONVECTION ARE ONGOING OVER NE GA AND
THE SRN FACING BLUE RIDGE OF SW NC. GENERAL CONSENSUS FROM
CONVECTION ALLOWING GUIDANCE IS THAT THE ACTIVITY WILL PROPAGATE
SEWD OVER THE NEXT 2-3 HRS. SOME DEVELOPMENT OF SHOWERS OR TSTMS
OVER THE NC PIEDMONT AND ERN UPSTATE CANNOT BE RULED OUT...BUT THE
LOOK OF CUMULUS ON SATELLITE SUGGESTS SPARSE COVERAGE AT BEST. A
COUPLE OF LIGHT RETURNS HAVE BEEN SEEN ON RADAR IN THESE AREAS...BUT
MODEL PROGS OF WIDESPREAD SMALL CELLS DEVELOPING JUST LOOKS
OVERDONE. POPS HAVE BEEN REDUCED BASICALLY EAST OF I-26.
AS OF 230 PM...CUMULUS CLOUDS HAVE CAPPED THE TEMP RUN UP SOMEWHAT
THIS AFTERNOON PARTICULARLY IN THE GREENVILLE-SPARTANBURG AREA.
THEREFORE...DIALED BACK THE MAX TEMPS BY A 2-3 DEGREES THOSE AREAS.
THE RISE AT CLT HAS SLOWED AS WELL SO THEY SHOULD COME UP SHY OF
100. CONVECTION FIRING OVER FAR WESTERN NC AND NE GA AS EXPECTED.
LATEST HRRR USES THE SFC TROUGH LAYING ACROSS UPSTATE SC INTO
WESTERN NC TO DEVELOP SCT THUNDERSTORMS BY LATE AFTERNOON. WITH
CAPES BETWEEN 2000-3000J AND DCAPES >1000J A FEW WET DAMAGING
MICROBURSTS ARE LIKELY. THE CONVECTION SHOULD ASH OUT DURING THE
EVENING WITH THE LOSS OF HEATING.
FOR THE OVERNIGHT...IT WILL BE A MUGGY NIGHT WITH CLEAR TO PARTLY
CLOUDY CONDITIONS. MIN TEMPS WILL BE WELL ABOVE CLIMO WITH LOW TO
MID 70S OUTSIDE THE MOUNTAINS AND LOW TO MID 60S MOUNTAINS.
THURSDAY WILL BE ANOTHER HOT DAY AS THE UPPER HIGH TO THE WEST
BEGINS TO SLIP EASTWARD BUT WEAKEN SOMEWHAT. ALSO SUBTLE CHANGES
OCCUR AT THE SURFACE AS THE WEAK BOUNDARY ACROSS THE AREA IS
FORECAST TO MOVE NORTHEAST AS A LOW MOVES THROUGH THE OHIO VALLEY.
HENCE...THE AMOUNT OF FORCING FOR THUNDERSTORMS WILL BE SOMEWHAT
LESS WITH SOME DEGREE OF SYNOPTIC SUBSIDENCE. HOWEVER...FORECAST
SOUNDINGS SHOW CIN ERODING IN THE AFTERNOON TO WHERE WE EXPECT A FEW
UPDRAFTS TO BREAK THE CAP. HENCE...WILL CARRY ISOLATED TO SCATTERED
POPS OVER THE MOUNTAINS AND THE SOUTHERN PIEDMONT. THE OTHER CONCERN
WILL CONTINUE TO BE THE HEAT. HAVE GONE ON THE HIGH END OF THE
GUIDANCE ENVELOPE FOR MAX TEMPS ON FRIDAY WHICH IS WHAT THE
THICKNESS WOULD SUPPORT. DEWPOINTS WILL TRY TO MIX OUT SOME DURING
THE AFTERNOON...BUT PROBABLY NOT ENOUGH TO PRECLUDE AN HOUR OR TWO
OF APPARENT TEMPS REACHING 105 ACROSS PARTS OF THE UPSTATE. IF
CURRENT NUMBERS HOLD...MAY HAVE TO CONSIDER A HEAT ADVISORY FOR
PARTS OF NE GA...UPSTATE SC AND PERHAPS THE CLT AREA.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 145 PM WEDNESDAY...THE BIG STORY OF THE SHORT TERM PERIOD WILL
BE THE SIGNIFICANT PATTERN CHANGE THAT IS ANTICIPATED...AS A
SIGNIFICANT SHORT WAVE DIVES OUT OF THE NORTHERN CONUS...AND CARVES
OUT A LONG WAVE TROUGH ACROSS THE EASTERN CONUS BY THE START OF THE
WEEKEND. SURFACE LOW PRESSURE TRACKING ALONG THE ASSOCIATED FRONTAL
ZONE...FROM THE TENN TO THE OHIO VALLEY IS EXPECTED TO ACTIVATE A
PSEUDO-WARM FRONT/E-W ORIENTED CONVERGENCE ZONE ACROSS THE REGION ON
FRIDAY...AND THIS COULD ACT AS AN ADDITIONAL FOCUS FOR CONVECTIVE
INITIATION ACROSS OUR AREA FRI AFTERNOON. HOWEVER...THERE ARE QUITE
A FEW MIXED SIGNALS IN THE GUIDANCE REGARDING HOW WIDESPREAD ANY
CONVECTION WILL BE DURING THE AFTERNOON. THE HIGHEST POPS (LIKELY)
WILL BE FOCUSED ACROSS THE NORTHERN ZONES...WHERE A MODEL CONSENSUS
SUGGESTS THE CONVERGENCE ZONE WILL RESIDE DURING PEAK HEATING...AND
ACROSS THE HIGH TERRAIN...WHERE THE COMBINATION OF TERRAIN EFFECTS
AND INCREASED CONVERGENCE SHOULD RESULT IN HIGHER THAN NORMAL
COVERAGE. DESPITE IMPROVING MID/UPPER FLOW RESPONDING TO HEIGHT
FALLS...SHEAR MAGNITUDE WILL REMAIN QUITE WEAK OWING TO
UNIDIRECTIONAL PROFILES. NEVERTHELESS...A FEW SEVERE STORMS WILL BE
POSSIBLE.
WITH HEIGHTS CONTINUING TO FALL AND AN APPROACHING FRONTAL ZONE...
GOOD CHANCES FOR CONVECTION ARE EXPECTED TO CONTINUE WELL INTO FRI
NIGHT...AND LIKELY POPS WILL ACTUALLY BE CARRIED THROUGH THE
OVERNIGHT HOURS...DUE TO THE POTENTIAL FOR PRE-FRONTAL CONVECTION
MOVING INTO THE FORECAST AREA...BUT ALSO DUE TO DEVELOPMENT OF AN
ANOMALOUSLY STRONG W/SW LOW LEVEL FLOW...WHICH COULD ALLOW FOR SOME
TERRAIN-INDUCED CONVECTION.
SATURDAY WILL FEATURE AMPLE GOOD SOURCES OF LIFT...WITH LOW LEVEL
CONVERGENCE ALONG THE FRONT...AND AN UPPER PATTERN SUPPORTIVE OF
UVV. HOWEVER...SATURDAY WILL BE THE MOST STABLE DAY OF THE WEEK AS
WELL...OWING TO THE LIKELIHOOD OF ABUNDANT MORNING CLOUD COVER AND
DEEP MOIST ADIABATIC LAPSE RATES. ON THE OTHER HAND...SHEAR WILL BE
RATHER IMPRESSIVE FOR LATE JUNE...ABOUT 30 KTS THROUGH A DEEP LAYER.
SOME UPSCALE ORGANIZATION COULD THEREFORE OCCUR IF POCKETS OF MORE
ROBUST INSTABILITY CAN BE REALIZED. LIKELY POPS WILL BE CARRIED
ACROSS THE MAJORITY OF THE AREA SAT AFTERNOON.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 300 PM WEDNESDAY...THE MEDIUM RANGE BEGINS SATURDAY NIGHT
WITH A FRONTAL BOUNDARY APPROACHING THE FORECAST AREA. POPS WILL
REMAIN ELEVATED THROUGH EARLY SUNDAY BEFORE THE FRONT CLEARS THE
REGION AND DRIER AIR WORKS IN. THE PLEASANT DRIER AND UNSEASONABLY
COOL REGIME WILL PERSIST THROUGH MONDAY AND PERHAPS EARLY TUESDAY.
LOW-LEVEL FLOW TURNS SOUTHWESTERLY ON TUESDAY...ADVECTING SLIGHTLY
WARMER AND MORE MOIST AIR INTO THE CWA. ANOTHER FRONT APPROACHES
THE AREA TOWARDS THE END OF THE PERIOD. MODEL DISCREPANCIES ON
TIMING AND ASSOCIATED QPF AMOUNTS REMAIN SIGNIFICANT THOUGH
INCREASED POPS TOWARDS THE END OF THE PERIOD ARE LIKELY.
GIVEN ABUNDANT CLOUD COVER ASSOCIATED WITH THE INITIAL FRONTAL
PASSAGE...TEMPS WILL BE 5-10 DEGREES BELOW CLIMO ON SUNDAY AND
MONDAY. HEADING INTO TUESDAY TEMPS WILL RECOVER TO NEAR NORMAL
VALUES AND REMAIN NEAR NORMAL THROUGH THE END OF THE PERIOD.
&&
.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
AT KCLT...A WEAK FRONTAL TROUGH IN THE VICINITY OF THE AIRFIELD
WILL SERVE TO TRIGGER ISOLD TO WIDELY SCT TSRA IN UNSTABLE AIRMASS.
HENCE...WILL CARRY A TEMPO TSRA FROM 22-00Z THIS AFTERNOON.
OTHERWISE...VFR CUMULUS WILL DISSIPATE AFTER SUNSET. WINDS SHOULD
PREVAIL NORTHERLY BUT OCNL VARIABILITY IS POSSIBLE DUE TO THE
PROXIMITY OF THE TROUGH...AND ANY NEARBY TSRA WILL PRODUCE GUSTY
OUTFLOWS.
ELSEWHERE...AIRMASS IS QUITE UNSTABLE OUTSIDE THE MOUNTAINS THIS
AFTERNOON ALONG WITH A WEAK FRONTAL TROUGH EXTENDING FROM WESTERN
NC...THROUGH UPSTATE SC INTO NE GA. SCATTERED THUNDERSTORMS ARE
EXPECTED TO DEVELOP BY MID AFTERNOON. CAMS FAVOR WESTERN AREAS WITH
THE BEST COVERAGE...SO WILL CARRY A TEMPO TSRA AT KAND. WILL MENTION
VCTS AT GSP AND GMU. THE CHANCE OF TSRA TOO LOW TO MENTION AT AVL
AND HKY. EXPECT SOME FOG FORMATION EARLY THURSDAY MORNING WITH
GUIDANCE SUGGESTING MVFR RESTRICTIONS AT AVL AND HKY.
OUTLOOK...TSTM CHANCES WILL INCREASE LATE IN THE WEEK INTO THE
WEEKEND AS A COLD FRONT EVENTUALLY APPROACHES FROM THE NW. MORNING
RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY
WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND IN THE MOUNTAIN RIVER
VALLEYS. BEHIND THE COLD FRONT...A MUCH DRYER AND COOLER AIRMASS
WILL OVERSPREAD THE REGION ON SUNDAY.
CONFIDENCE TABLE...
21-03Z 03-09Z 09-15Z 15-18Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 91% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 91% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 91% HIGH 100%
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
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE
VALUES WERE LAST REACHED.
WEDNESDAY JUNE 24...
AVL 94 1952
CLT 102 1930
GSP 100 1952
THURSDAY JUNE 25...
AVL 96 1952
CLT 102 1914
GSP 101 1952
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...LEV
NEAR TERM...LG/WIMBERLEY
SHORT TERM...JDL
LONG TERM...JP/LEV
AVIATION...LG/WIMBERLEY
CLIMATE...GSP
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
346 PM EDT WED JUN 24 2015
.SYNOPSIS...
STRONG MID LEVEL HIGH PRESSURE WILL PERSIST ACROSS THE REGION
THROUGH THE REMAINDER OF THE WORK WEEK...MAINTAINING WELL ABOVE
NORMAL TEMPERATURES. A BROAD UPPER LEVEL TROF WILL MOVE OVER THE
REGION OVER THE WEEKEND RETURNING TEMPERATURES TO SEASONAL LEVELS BY
SUNDAY AND INCREASING CHANCES FOR WIDESPREAD SHOWERS AND
THUNDERSTORMS. A COOLER AND DRIER PATTERN WILL TAKE SHAPE AFTER A
FRONT PASSES EARLY IN THE WEEK BEFORE ANOTHER FRONTAL BOUNDARY
APPROACHES THE AREA LATER NEXT WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 230 PM...CUMULUS CLOUDS HAVE CAPPED THE TEMP RUN UP SOMEWHAT
THIS AFTERNOON PARTICULARLY IN THE GREENVILLE-SPARTANBURG AREA.
THEREFORE...DIALED BACK THE MAX TEMPS BY A 2-3 DEGREES THOSE AREAS.
THE RISE AT CLT HAS SLOWED AS WELL SO THEY SHOULD COME UP SHY OF
100. CONVECTION FIRING OVER FAR WESTERN NC AND NE GA AS EXPECTED.
LATEST HRRR USES THE SFC TROUGH LAYING ACROSS UPSTATE SC INTO
WESTERN NC TO DEVELOP SCT THUNDERSTORMS BY LATE AFTERNOON. WITH
CAPES BETWEEN 2000-3000J AND DCAPES >1000J A FEW WET DAMAGING
MICROBURSTS ARE LIKELY. THE CONVECTION SHOULD ASH OUT DURING THE
EVENING WITH THE LOSS OF HEATING.
FOR THE OVERNIGHT...IT WILL BE A MUGGY NIGHT WITH CLEAR TO PARTLY
CLOUDY CONDITIONS. MIN TEMPS WILL BE WELL ABOVE CLIMO WITH LOW TO
MID 70S OUTSIDE THE MOUNTAINS AND LOW TO MID 60S MOUNTAINS.
THURSDAY WILL BE ANOTHER HOT DAY AS THE UPPER HIGH TO THE WEST
BEGINS TO SLIP EASTWARD BUT WEAKEN SOMEWHAT. ALSO SUBTLE CHANGES
OCCUR AT THE SURFACE AS THE WEAK BOUNDARY ACROSS THE AREA IS
FORECAST TO MOVE NORTHEAST AS A LOW MOVES THROUGH THE OHIO VALLEY.
HENCE...THE AMOUNT OF FORCING FOR THUNDERSTORMS WILL BE SOMEWHAT
LESS WITH SOME DEGREE OF SYNOPTIC SUBSIDENCE. HOWEVER...FORECAST
SOUNDINGS SHOW CIN ERODING IN THE AFTERNOON TO WHERE WE EXPECT A FEW
UPDRAFTS TO BREAK THE CAP. HENCE...WILL CARRY ISOLATED TO SCATTERED
POPS OVER THE MOUNTAINS AND THE SOUTHERN PIEDMONT. THE OTHER CONCERN
WILL CONTINUE TO BE THE HEAT. HAVE GONE ON THE HIGH END OF THE
GUIDANCE ENVELOPE FOR MAX TEMPS ON FRIDAY WHICH IS WHAT THE
THICKNESS WOULD SUPPORT. DEWPOINTS WILL TRY TO MIX OUT SOME
DURING THE AFTERNOON...BUT PROBABLY NOT ENOUGH TO PRECLUDE AN HOUR
OR TWO OF APPARENT TEMPS REACHING 105 ACROSS PARTS OF THE UPSTATE.
IF CURRENT NUMBERS HOLD...MAY HAVE TO CONSIDER A HEAT ADVISORY FOR
PARTS OF NE GA...UPSTATE SC AND PERHAPS THE CLT AREA.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 145 PM WEDNESDAY...THE BIG STORY OF THE SHORT TERM PERIOD WILL
BE THE SIGNIFICANT PATTERN CHANGE THAT IS ANTICIPATED...AS A
SIGNIFICANT SHORT WAVE DIVES OUT OF THE NORTHERN CONUS...AND CARVES
OUT A LONG WAVE TROUGH ACROSS THE EASTERN CONUS BY THE START OF THE
WEEKEND. SURFACE LOW PRESSURE TRACKING ALONG THE ASSOCIATED FRONTAL
ZONE...FROM THE TENN TO THE OHIO VALLEY IS EXPECTED TO ACTIVATE A
PSEUDO-WARM FRONT/E-W ORIENTED CONVERGENCE ZONE ACROSS THE REGION ON
FRIDAY...AND THIS COULD ACT AS AN ADDITIONAL FOCUS FOR CONVECTIVE
INITIATION ACROSS OUR AREA FRI AFTERNOON. HOWEVER...THERE ARE QUITE
A FEW MIXED SIGNALS IN THE GUIDANCE REGARDING HOW WIDESPREAD ANY
CONVECTION WILL BE DURING THE AFTERNOON. THE HIGHEST POPS (LIKELY)
WILL BE FOCUSED ACROSS THE NORTHERN ZONES...WHERE A MODEL CONSENSUS
SUGGESTS THE CONVERGENCE ZONE WILL RESIDE DURING PEAK HEATING...AND
ACROSS THE HIGH TERRAIN...WHERE THE COMBINATION OF TERRAIN EFFECTS
AND INCREASED CONVERGENCE SHOULD RESULT IN HIGHER THAN NORMAL
COVERAGE. DESPITE IMPROVING MID/UPPER FLOW RESPONDING TO HEIGHT
FALLS...SHEAR MAGNITUDE WILL REMAIN QUITE WEAK OWING TO
UNIDIRECTIONAL PROFILES. NEVERTHELESS...A FEW SEVERE STORMS WILL BE
POSSIBLE.
WITH HEIGHTS CONTINUING TO FALL AND AN APPROACHING FRONTAL ZONE...
GOOD CHANCES FOR CONVECTION ARE EXPECTED TO CONTINUE WELL INTO FRI
NIGHT...AND LIKELY POPS WILL ACTUALLY BE CARRIED THROUGH THE
OVERNIGHT HOURS...DUE TO THE POTENTIAL FOR PRE-FRONTAL CONVECTION
MOVING INTO THE FORECAST AREA...BUT ALSO DUE TO DEVELOPMENT OF AN
ANOMALOUSLY STRONG W/SW LOW LEVEL FLOW...WHICH COULD ALLOW FOR SOME
TERRAIN-INDUCED CONVECTION.
SATURDAY WILL FEATURE AMPLE GOOD SOURCES OF LIFT...WITH LOW LEVEL
CONVERGENCE ALONG THE FRONT...AND AN UPPER PATTERN SUPPORTIVE OF
UVV. HOWEVER...SATURDAY WILL BE THE MOST STABLE DAY OF THE WEEK AS
WELL...OWING TO THE LIKELIHOOD OF ABUNDANT MORNING CLOUD COVER AND
DEEP MOIST ADIABATIC LAPSE RATES. ON THE OTHER HAND...SHEAR WILL BE
RATHER IMPRESSIVE FOR LATE JUNE...ABOUT 30 KTS THROUGH A DEEP LAYER.
SOME UPSCALE ORGANIZATION COULD THEREFORE OCCUR IF POCKETS OF MORE
ROBUST INSTABILITY CAN BE REALIZED. LIKELY POPS WILL BE CARRIED
ACROSS THE MAJORITY OF THE AREA SAT AFTERNOON.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 300 PM WEDNESDAY...THE MEDIUM RANGE BEGINS SATURDAY NIGHT
WITH A FRONTAL BOUNDARY APPROACHING THE FORECAST AREA. POPS WILL
REMAIN ELEVATED THROUGH EARLY SUNDAY BEFORE THE FRONT CLEARS THE
REGION AND DRIER AIR WORKS IN. THE PLEASANT DRIER AND UNSEASONABLY
COOL REGIME WILL PERSIST THROUGH MONDAY AND PERHAPS EARLY TUESDAY.
LOW-LEVEL FLOW TURNS SOUTHWESTERLY ON TUESDAY...ADVECTING SLIGHTLY
WARMER AND MORE MOIST AIR INTO THE CWA. ANOTHER FRONT APPROACHES
THE AREA TOWARDS THE END OF THE PERIOD. MODEL DISCREPANCIES ON
TIMING AND ASSOCIATED QPF AMOUNTS REMAIN SIGNIFICANT THOUGH
INCREASED POPS TOWARDS THE END OF THE PERIOD ARE LIKELY.
GIVEN ABUNDANT CLOUD COVER ASSOCIATED WITH THE INITIAL FRONTAL
PASSAGE...TEMPS WILL BE 5-10 DEGREES BELOW CLIMO ON SUNDAY AND
MONDAY. HEADING INTO TUESDAY TEMPS WILL RECOVER TO NEAR NORMAL
VALUES AND REMAIN NEAR NORMAL THROUGH THE END OF THE PERIOD.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
AT KCLT...A WEAK FRONTAL TROUGH IN THE VICINITY OF THE AIRFIELD
WILL SERVE TO TRIGGER SCT TSRA AS AIRMASS IS QUITE UNSTABLE THIS
AFTERNOON. HENCE...WILL CARRY A TEMPO TSRA FROM 21-23Z THIS
AFTERNOON. OTHERWISE...VFR CUMULUS WILL DISSIPATE AFTER SUNSET.
ELSEWHERE...AIRMASS IS QUITE UNSTABLE OUTSIDE THE MOUNTAINS THIS
AFTERNOON ALONG WITH A WEAK FRONTAL TROUGH EXTENDING FROM WESTERN
NC...THROUGH UPSTATE SC INTO NE GA. SCATTERED THUNDERSTORMS ARE
EXPECTED TO DEVELOP BY MID AFTERNOON. CAMS FAVOR WESTERN AREAS WITH
THE BEST COVERAGE...SO WILL CARRY A TEMPO TSRA AT KAND. WILL MENTION
VCTS AT GSP AND GMU. THE CHANCE OF TSRA TOO LOW TO MENTION AT AVL
AND HKY. EXPECT SOME FOG FORMATION EARLY THURSDAY MORNING WITH
GUIDANCE SUGGESTING MVFR RESTRICTIONS AT AVL AND HKY.
OUTLOOK...TSTM CHANCES WILL INCREASE LATE IN THE WEEK INTO THE
WEEKEND AS A COLD FRONT EVENTUALLY APPROACHES FROM THE NW. MORNING
RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY
WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND IN THE MOUNTAIN RIVER
VALLEYS. BEHIND THE COLD FRONT...A MUCH DRYER AND COOLER AIRMASS
WILL OVERSPREAD THE REGION ON SUNDAY.
CONFIDENCE TABLE...
19-01Z 01-07Z 07-13Z 13-18Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 86% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 96% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 93% HIGH 100%
KGMU HIGH 86% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 93% HIGH 100%
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
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE
VALUES WERE LAST REACHED.
THURSDAY JUNE 25...
AVL 96 1952
CLT 102 1914
GSP 101 1952
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...LEV
NEAR TERM...LG
SHORT TERM...JDL
LONG TERM...JP/LEV
AVIATION...LG
CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
252 PM EDT WED JUN 24 2015
.SYNOPSIS...
STRONG MID LEVEL HIGH PRESSURE WILL PERSIST ACROSS THE REGION
THROUGH THE REMAINDER OF THE WORK WEEK...MAINTAINING WELL ABOVE
NORMAL TEMPERATURES. A BROAD UPPER LEVEL TROF WILL MOVE OVER THE
REGION OVER THE WEEKEND RETURNING TEMPERATURES TO SEASONAL LEVELS BY
SUNDAY AND INCREASING CHANCES FOR WIDESPREAD SHOWERS AND
THUNDERSTORMS. A COOLER AND DRIER PATTERN WILL TAKE SHAPE AFTER A
FRONT PASSES EARLY IN THE WEEK BEFORE ANOTHER FRONTAL BOUNDARY
APPROACHES THE AREA LATER NEXT WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 230 PM...CUMULUS CLOUDS HAVE CAPPED THE TEMP RUN UP SOMEWHAT
THIS AFTERNOON PARTICULARLY IN THE GREENVILLE-SPARTANBURG AREA.
THEREFORE...DIALED BACK THE MAX TEMPS BY A 2-3 DEGREES THOSE AREAS.
THE RISE AT CLT HAS SLOWED AS WELL SO THEY SHOULD COME UP SHY OF
100. CONVECTION FIRING OVER FAR WESTERN NC AND NE GA AS EXPECTED.
LATEST HRRR USES THE SFC TROUGH LAYING ACROSS UPSTATE SC INTO
WESTERN NC TO DEVELOP SCT THUNDERSTORMS BY LATE AFTERNOON. WITH
CAPES BETWEEN 2000-3000J AND DCAPES >1000J A FEW WET DAMAGING
MICROBURSTS ARE LIKELY. THE CONVECTION SHOULD ASH OUT DURING THE
EVENING WITH THE LOSS OF HEATING.
FOR THE OVERNIGHT...IT WILL BE A MUGGY NIGHT WITH CLEAR TO PARTLY
CLOUDY CONDITIONS. MIN TEMPS WILL BE WELL ABOVE CLIMO WITH LOW TO
MID 70S OUTSIDE THE MOUNTAINS AND LOW TO MID 60S MOUNTAINS.
THURSDAY WILL BE ANOTHER HOT DAY AS THE UPPER HIGH TO THE WEST
BEGINS TO SLIP EASTWARD BUT WEAKEN SOMEWHAT. ALSO SUBTLE CHANGES
OCCUR AT THE SURFACE AS THE WEAK BOUNDARY ACROSS THE AREA IS
FORECAST TO MOVE NORTHEAST AS A LOW MOVES THROUGH THE OHIO VALLEY.
HENCE...THE AMOUNT OF FORCING FOR THUNDERSTORMS WILL BE SOMEWHAT
LESS WITH SOME DEGREE OF SYNOPTIC SUBSIDENCE. HOWEVER...FORECAST
SOUNDINGS SHOW CIN ERODING IN THE AFTERNOON TO WHERE WE EXPECT A
FEW UPDRAFTS TO BREAK THE CAP. HENCE...WILL CARRY ISOLATED TO
SCATTERED POPS OVER THE MOUNTAINS AND THE SOUTHERN PIEDMONT. THE
OTHER CONCERN WILL CONTINUE TO BE THE HEAT. HAVE GONE ON THE HIGH
END OF THE GUIDANCE ENVELOPE FOR MAX TEMPS ON FRIDAY WHICH IS WHAT
THE THICKNESS WOULD SUPPORT. DEWPOINTS WILL TRY TO MIX OUT SOME
DURING THE AFTERNOON...BUT PROBABLY NOT ENOUGH TO PRECLUDE AN HOUR
OR TWO OF APPARENT TEMPS REACHING 105 ACROSS PARTS OF THE UPSTATE.
IF CURRENT NUMBERS HOLD...MAY HAVE TO CONSIDER A HEAT ADVISORY FOR
PARTS OF NE GA...UPSTATE SC AND PERHAPS THE CLT AREA.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 145 PM WEDNESDAY...THE BIG STORY OF THE SHORT TERM PERIOD WILL
BE THE SIGNIFICANT PATTERN CHANGE THAT IS ANTICIPATED...AS A
SIGNIFICANT SHORT WAVE DIVES OUT OF THE NORTHERN CONUS...AND CARVES
OUT A LONG WAVE TROUGH ACROSS THE EASTERN CONUS BY THE START OF THE
WEEKEND. SURFACE LOW PRESSURE TRACKING ALONG THE ASSOCIATED FRONTAL
ZONE...FROM THE TENN TO THE OHIO VALLEY IS EXPECTED TO ACTIVATE A
PSEUDO-WARM FRONT/E-W ORIENTED CONVERGENCE ZONE ACROSS THE REGION ON
FRIDAY...AND THIS COULD ACT AS AN ADDITIONAL FOCUS FOR CONVECTIVE
INITIATION ACROSS OUR AREA FRI AFTERNOON. HOWEVER...THERE ARE QUITE
A FEW MIXED SIGNALS IN THE GUIDANCE REGARDING HOW WIDESPREAD ANY
CONVECTION WILL BE DURING THE AFTERNOON. THE HIGHEST POPS (LIKELY)
WILL BE FOCUSED ACROSS THE NORTHERN ZONES...WHERE A MODEL CONSENSUS
SUGGESTS THE CONVERGENCE ZONE WILL RESIDE DURING PEAK HEATING...AND
ACROSS THE HIGH TERRAIN...WHERE THE COMBINATION OF TERRAIN EFFECTS
AND INCREASED CONVERGENCE SHOULD RESULT IN HIGHER THAN NORMAL
COVERAGE. DESPITE IMPROVING MID/UPPER FLOW RESPONDING TO HEIGHT
FALLS...SHEAR MAGNITUDE WILL REMAIN QUITE WEAK OWING TO
UNIDIRECTIONAL PROFILES. NEVERTHELESS...A FEW SEVERE STORMS WILL BE
POSSIBLE.
WITH HEIGHTS CONTINUING TO FALL AND AN APPROACHING FRONTAL ZONE...
GOOD CHANCES FOR CONVECTION ARE EXPECTED TO CONTINUE WELL INTO FRI
NIGHT...AND LIKELY POPS WILL ACTUALLY BE CARRIED THROUGH THE
OVERNIGHT HOURS...DUE TO THE POTENTIAL FOR PRE-FRONTAL CONVECTION
MOVING INTO THE FORECAST AREA...BUT ALSO DUE TO DEVELOPMENT OF AN
ANOMALOUSLY STRONG W/SW LOW LEVEL FLOW...WHICH COULD ALLOW FOR SOME
TERRAIN-INDUCED CONVECTION.
SATURDAY WILL FEATURE AMPLE GOOD SOURCES OF LIFT...WITH LOW LEVEL
CONVERGENCE ALONG THE FRONT...AND AN UPPER PATTERN SUPPORTIVE OF
UVV. HOWEVER...SATURDAY WILL BE THE MOST STABLE DAY OF THE WEEK AS
WELL...OWING TO THE LIKELIHOOD OF ABUNDANT MORNING CLOUD COVER AND
DEEP MOIST ADIABATIC LAPSE RATES. ON THE OTHER HAND...SHEAR WILL BE
RATHER IMPRESSIVE FOR LATE JUNE...ABOUT 30 KTS THROUGH A DEEP LAYER.
SOME UPSCALE ORGANIZATION COULD THEREFORE OCCUR IF POCKETS OF MORE
ROBUST INSTABILITY CAN BE REALIZED. LIKELY POPS WILL BE CARRIED
ACROSS THE MAJORITY OF THE AREA SAT AFTERNOON.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 3 AM WEDNESDAY...SIGNIFICANT PATTERN CHANGE WILL SETTLE OVER
THE REGION THIS WEEKEND AND SHOULD REMAIN THROUGH THE EXTENDED
PERIOD. MODELS INDICATE THAT THE AXIS OF A L/W TROUGH WILL SWEEP
ACROSS THE REGION THIS WEEKEND...WITH A SECONDARY WAVE EXPECTED TO
CROSS THE APPALACHIANS ON TUESDAY. AT THE SFC...THE CENTER OF A
DEEPENING LOW WILL MOVE FROM THE OHIO RIVER VALLEY ON SATURDAY TO
SOUTHERN NY BY SUNDAY EVENING. A COLD FRONT SHOULD PUSH ACROSS THE
REGION LATE SATURDAY AFTERNOON AND EVENING. THE ENVIRONMENT AHEAD OF
THE FRONT WILL FEATURE WIDESPREAD INSTABILITY AND WEAK
SHEAR...POSSIBLY SUPPORTING A BAND OF TSRA SAT AFTERNOON. I WILL
FORECAST CATE COVERAGE NEAR THE TN LINE...WITH GENERALLY LIKELY POPS
ACROSS THE REST OF THE CWA. DRIER AIR WILL BUILD ACROSS THE REGION
ON SUNDAY...RESULTING IN FALLING POP VALUES. I WILL FORECAST
PRIMARILY DIURNAL POPS ACROSS THE REGION MON AND TUES. TEMPERATURES
THROUGH THE EXTENDED ARE FORECAST TO RANGE FROM BELOW NORMAL THIS
WEEKEND TO NEAR NORMAL BY TUESDAY.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
AT KCLT...A WEAK FRONTAL TROUGH IN THE VICINTY OF THE AIRFIELD WILL
SERVE TO TRIGGER SCT TSRA AS AIRMASS IS QUITE UNSTABLE THIS
AFTERNOON. HENCE...WILL CARRY A TEMPO TSRA FROM 21-23Z THIS
AFTERNOON. OTHERWISE...VFR CUMULUS WILL DISSIPATE AFTER SUNSET.
ELSEWHERE...AIRMASS IS QUITE UNSTABLE OUTSIDE THE MOUNTAINS THIS
AFTERNOON ALONG WITH A WEAK FRONTAL TROUGH EXTENDING FROM WESTERN
NC...THROUGH UPSTATE SC INTO NE GA. SCATTERED THUNDERSTORMS ARE
EXPECTED TO DEVELOP BY MID AFTERNOON. CAMS FAVOR WESTERN AREAS WITH
THE BEST COVERAGE...SO WILL CARRY A TEMPO TSRA AT KAND. WILL MENTION
VCTS AT GSP AND GMU. THE CHANCE OF TSRA TOO LOW TO MENTION AT AVL
AND HKY. EXPECT SOME FOG FORMATION EARLY THURSDAY MORNING WITH
GUIDNACE SUGGESTING MVFR RESTRICTIONS AT AVL AND HKY.
OUTLOOK...TSTM CHANCES WILL INCREASE LATE IN THE WEEK INTO THE
WEEKEND AS A COLD FRONT EVENTUALLY APPROACHES FROM THE NW. MORNING
RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY
WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND IN THE MOUNTAIN RIVER
VALLEYS. BEHIND THE COLD FRONT...A MUCH DRYER AND COOLER AIRMASS
WILL OVERSPREAD THE REGION ON SUNDAY.
CONFIDENCE TABLE...
19-01Z 01-07Z 07-13Z 13-18Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 86% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 96% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 93% HIGH 100%
KGMU HIGH 86% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 93% HIGH 100%
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
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE
VALUES WERE LAST REACHED.
WEDNESDAY JUNE 24...
AVL 94 1952
CLT 102 1930
GSP 100 1952
THURSDAY JUNE 25...
AVL 96 1952
CLT 102 1914
GSP 101 1952
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...LEV
NEAR TERM...LG
SHORT TERM...JDL
LONG TERM...JP/LEV
AVIATION...LG
CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
707 AM EDT WED JUN 24 2015
.SYNOPSIS...
STRONG MID LEVEL HIGH PRESSURE WILL PERSIST ACROSS THE REGION
THROUGH THE REMAINDER OF THE WORK WEEK...MAINTAINING WELL ABOVE
NORMAL TEMPERATURES. A BROAD UPPER LEVEL TROF WILL MOVE OVER THE
REGION OVER THE WEEKEND RETURNING TEMPERATURES TO SEASONAL LEVELS BY
SUNDAY AND INCREASING CHANCES FOR WIDESPREAD SHOWERS AND
THUNDERSTORMS. A COOLER AND DRIER PATTERN WILL TAKE SHAPE AFTER A
FRONT PASSES EARLY IN THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 700 AM EDT...DEBRIS CLOUDS HAVE KEPT ANY MORNING VALLEY FOG TO
A MINIMUM. OTHERWISE...THE WEAK SURFACE FRONTAL BOUNDARY IS FORECAST
TO STALL OVER THE FORECAST AREA TODAY AND THEN GRADUALLY LIFT
NORTHWARD AS A WARM FRONT TONIGHT. THE HRRR CONTINUES TO TREND
TOWARD BETTER TSTM COVERAGE IN SRN SECTIONS THIS AFTN...SOUTH OF THE
BOUNDARY. MODEL PROFILES REMAIN FAIRLY WARM ALOFT...HOWEVER...SEVERE
WEATHER WILL BE A THREAT WITH ANY TSTMS THAT FORM AS MODERATE OR
BETTER CAPE LOOKS LIKELY ALONG WITH MID LEVEL DRY AIR AND ASSOCIATED
THETA E LAPSES YIELDING SOME MEASURE OF MICROBURST POTENTIAL. THE
SRN HALF WILL BE MOST AT RISK GIVEN THE BOUNDARY LOCATION AND LIKELY
SBCAPE VALUES OF 3000 TO 3500 J/KG THERE DURING PEAK HEATING.
TEMPERATURES AND ASSOCIATED HEAT INDEX VALUES WILL BE THE OTHER
ISSUE FOR THE FORECAST TODAY. BL AND 850 TEMPS LOOK COMPARABLE TO
YESTERDAY...BUT SO DOES THE POTENTIAL FOR SOME DEWPOINT MIXING IN
THE WARMEST PIEDMONT SECTIONS. PLUS...THERE COULD BE DEBRIS CLOUDS
AROUND AT TIMES TODAY. WILL KEEP HEAT INDEX VALUES IN THE SRN
PIEDMONT AT 100 TO 104 THIS AFTN. ANTICIPATE ANOTHER VERY MILD NIGHT
WITH PRECIPITATION CHANCES STEADILY WANING WITH THE LOSS OF HEATING.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
AS OF 245 AM WEDNESDAY...ON THURSDAY...THE H5 AND H7 RIDGE WILL
REMAIN CENTERED OVER THE DEEP SOUTH. HOWEVER...HEIGHTS SHOULD RISE
FROM THE SOUTH AS THE RIDGE CENTER DRIFTS EAST DURING THE DAY. USING
A BLEND OF PREFERRED GUIDANCE...I WILL FORECAST HIGHS AROUND 90
WITHIN THE MTN VALLEYS TO MID TO HIGH 90S ACROSS THE FOOTHILLS AND
PIEDMONT. A WEST TO EAST FRONT WILL REMAIN ACROSS THE OHIO RIVER
VALLEYS AS A SFC TROF COVERS THE FOOTHILLS AND PIEDMONT. GIVEN THE
SFC PATTERN...LLVL WINDS ARE FORECAST TO REMAIN LIGHT FROM THE WSW.
FORECAST SOUNDINGS REVEAL THAT A SIGNIFICANT LAYER OF CIN WILL
REMAIN AROUND H75...VALUES RANGING FROM 40-60 J/KG. THE LACK OF
FORCING AND LINGERING CAPPING SHOULD FAVOR LITTLE TO NO COVERAGE OF
DEEP CONVECTION ON THURSDAY. I WILL FORECAST DRY CONDITIONS EAST OF
THE MTNS...WITH SCHC OVER THE RIDGES.
ON FRIDAY...SHORT RANGE MODELS INDICATE THAT A WEAK MID LEVEL LOW
WILL LINGER NEAR THE GA/FL LINE DURING THE DAY. IN ADDITION...A
POSITIVE TILTED L/W TROF WILL BEGIN TO AMPLIFY ACROSS THE MID
WEST...SLIDING EAST. AT THE SFC...A BROAD AREA OF LOW PRESSURE IS
EXPECTED TO DEVELOP ACROSS THE CAROLINAS AS A SFC FRONT STALLS OVER
THE REGION. FORECAST SOUNDINGS INDICATE THAT MOISTURE WILL SURGE
ACROSS THE REGION...WITH PW VALUES OVER 2 INCHES BY THE AFTERNOON.
THE MOISTURE COMBINED WITH WELL ABOVE AVERAGE HIGH TEMPERATURES
SHOULD YIELD WIDESPREAD MODERATE VALUES OF CAPE. GIVEN THE BROAD
AREA OF LLVL MOISTURE CONVERGENCE...INSTABILITY...AND INCREASING MID
LEVEL FORCING...TSRA COVERAGE WILL INCREASE SIGNIFICANTLY FROM
THURSDAY. I WILL FORECAST LIKELY POPS ACROSS THE MTNS WITH VALUES IN
THE 40 TO 50 RANGE EAST.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...SIGNIFICANT PATTERN CHANGE WILL SETTLE OVER
THE REGION THIS WEEKEND AND SHOULD REMAIN THROUGH THE EXTENDED
PERIOD. MODELS INDICATE THAT THE AXIS OF A L/W TROUGH WILL SWEEP
ACROSS THE REGION THIS WEEKEND...WITH A SECONDARY WAVE EXPECTED TO
CROSS THE APPALACHIANS ON TUESDAY. AT THE SFC...THE CENTER OF A
DEEPENING LOW WILL MOVE FROM THE OHIO RIVER VALLEY ON SATURDAY TO
SOUTHERN NY BY SUNDAY EVENING. A COLD FRONT SHOULD PUSH ACROSS THE
REGION LATE SATURDAY AFTERNOON AND EVENING. THE ENVIRONMENT AHEAD OF
THE FRONT WILL FEATURE WIDESPREAD INSTABILITY AND WEAK
SHEAR...POSSIBLY SUPPORTING A BAND OF TSRA SAT AFTERNOON. I WILL
FORECAST CATE COVERAGE NEAR THE TN LINE...WITH GENERALLY LIKELY POPS
ACROSS THE REST OF THE CWA. DRIER AIR WILL BUILD ACROSS THE REGION
ON SUNDAY...RESULTING IN FALLING POP VALUES. I WILL FORECAST
PRIMARILY DIURNAL POPS ACROSS THE REGION MON AND TUES. TEMPERATURES
THROUGH THE EXTENDED ARE FORECAST TO RANGE FROM BELOW NORMAL THIS
WEEKEND TO NEAR NORMAL BY TUESDAY.
&&
.AVIATION /11Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...A WEAK FRONT SAGGING SOUTH ACROSS THE TERMINAL AREA THIS
MORNING WILL TOGGLE SURFACE WINDS TO NE LATE MORNING THROUGH THE
AFTN. PRECIPITATION CHANCES LOOK RATHER SMALL AROUND THE AIRFIELD
GIVEN THE WARM PROFILES ALOFT...BUT ANY CONVECTION THAT FORMS WILL
BE STRONG. VFR CONDITIONS WILL CONTINUE WITH HIGH BASED CUMULUS
FORMING AND BEING TOPPED BY TEMPO HIGH CLOUD DEBRIS CIGS FROM TIME
TO TIME.
ELSEWHERE...CONVECTIVE CHANCES REMAIN GREATEST AT KAVL THIS AFTN DUE
TO TERRAIN FLOW AND LOW LEVEL CONVERGENCE...BUT A TSRA CANNOT BE
RULED OUT ACROSS THE UPSTATE SITES WHERE INSTABILITY WILL BE THE
GREATEST. ANY TSRA WOULD BE QUITE STRONG WITH THE POTENTIAL FOR
GUSTY WINDS GIVEN THE MID LEVEL DRY AIR. EXPECT SFC WINDS TO TOGGLE
NW THEN NE THROUGH THE DAY BEFORE TURNING AROUND THE DIAL TO SE
LATE. THE BEST CHANCE FOR RESTRICTIONS EARLY THU MORNING WILL BE IN
THE MTN VALLEYS...BUT WILL CONFINE THE FOG TO MVFR AT KAVL FOR NOW.
OUTLOOK...SCT DIURNAL TSTM CHANCES WILL INCREASE LATE WEEK INTO THE
WEEKEND AS A COLD FRONT EVENTUALLY APPROACHES FROM THE NW. MORNING
RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY
WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND IN THE MOUNTAIN RIVER
VALLEYS.
CONFIDENCE TABLE...
11-17Z 17-23Z 23-05Z 05-06Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 94% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
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
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE
VALUES WERE LAST REACHED.
WEDNESDAY JUNE 24...
AVL 94 1952
CLT 102 1930
GSP 100 1952
THURSDAY JUNE 25...
AVL 96 1952
CLT 102 1914
GSP 101 1952
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...NED
NEAR TERM...HG
SHORT TERM...NED
LONG TERM...NED
AVIATION...HG
CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
452 AM EDT WED JUN 24 2015
.SYNOPSIS...
STRONG MID LEVEL HIGH PRESSURE WILL PERSIST ACROSS THE REGION
THROUGH THE REMAINDER OF THE WORK WEEK...MAINTAINING WELL ABOVE
NORMAL TEMPERATURES. A BROAD UPPER LEVEL TROF WILL MOVE OVER THE
REGION OVER THE WEEKEND RETURNING TEMPERATURES TO SEASONAL LEVELS BY
SUNDAY AND INCREASING CHANCES FOR WIDESPREAD SHOWERS AND
THUNDERSTORMS. A COOLER AND DRIER PATTERN WILL TAKE SHAPE AFTER A
FRONT PASSES EARLY IN THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 445 AM EDT...THE LATEST HRRR RUNS ALLOW ANY LINGERING ERN TN
CONVECTION TO DIMINISH OVER THE WESTERN MOUNTAINS THROUGH DAYBREAK.
OTHERWISE...THE WEAK SURFACE FRONTAL BOUNDARY WILL STALL IN THE
FORECAST AREA TODAY AND THEN LIKELY LIFT NORTHWARD AS A WARM FRONT
TONIGHT. THE HRRR HAS ALSO TRENDED TOWARD BETTER TSTM COVERAGE IN
SRN SECTIONS THIS AFTN...SOUTH OF THE BOUNDARY. MODEL PROFILES
REMAIN FAIRLY WARM ALOFT...HOWEVER...SEVERE WEATHER WILL BE A THREAT
WITH ANY TSTMS THAT FORM AS MODERATE OR BETTER CAPE LOOKS LIKELY
ALONG WITH MID LEVEL DRY AIR AND ASSOCIATED THETA E LAPSES YIELDING
SOME MEASURE OF MICROBURST POTENTIAL. THE SRN HALF WILL BE MOST AT
RISK GIVEN THE BOUNDARY LOCATION AND LIKELY SBCAPE VALUES OF 3000 TO
3500 J/KG THERE DURING PEAK HEATING.
TEMPERATURES AND ASSOCIATED HEAT INDEX VALUES WILL BE THE OTHER
ISSUE FOR THE FORECAST TODAY. BL AND 850 TEMPS LOOK COMPARABLE TO
YESTERDAY...BUT SO DOES THE POTENTIAL FOR SOME DEWPOINT MIXING IN
THE WARMEST PIEDMONT SECTIONS. PLUS...THERE COULD BE DEBRIS CLOUDS
AROUND AT TIMES TODAY. WILL KEEP HEAT INDEX VALUES IN THE SRN
PIEDMONT AT 100 TO 104 THIS AFTN. ANTICIPATE ANOTHER VERY MILD NIGHT
WITH PRECIPITATION CHANCES STEADILY WANING WITH THE LOSS OF HEATING.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
AS OF 245 AM WEDNESDAY...ON THURSDAY...THE H5 AND H7 RIDGE WILL
REMAIN CENTERED OVER THE DEEP SOUTH. HOWEVER...HEIGHTS SHOULD RISE
FROM THE SOUTH AS THE RIDGE CENTER DRIFTS EAST DURING THE DAY. USING
A BLEND OF PREFERRED GUIDANCE...I WILL FORECAST HIGHS AROUND 90
WITHIN THE MTN VALLEYS TO MID TO HIGH 90S ACROSS THE FOOTHILLS AND
PIEDMONT. A WEST TO EAST FRONT WILL REMAIN ACROSS THE OHIO RIVER
VALLEYS AS A SFC TROF COVERS THE FOOTHILLS AND PIEDMONT. GIVEN THE
SFC PATTERN...LLVL WINDS ARE FORECAST TO REMAIN LIGHT FROM THE WSW.
FORECAST SOUNDINGS REVEAL THAT A SIGNIFICANT LAYER OF CIN WILL
REMAIN AROUND H75...VALUES RANGING FROM 40-60 J/KG. THE LACK OF
FORCING AND LINGERING CAPPING SHOULD FAVOR LITTLE TO NO COVERAGE OF
DEEP CONVECTION ON THURSDAY. I WILL FORECAST DRY CONDITIONS EAST OF
THE MTNS...WITH SCHC OVER THE RIDGES.
ON FRIDAY...SHORT RANGE MODELS INDICATE THAT A WEAK MID LEVEL LOW
WILL LINGER NEAR THE GA/FL LINE DURING THE DAY. IN ADDITION...A
POSITIVE TILTED L/W TROF WILL BEGIN TO AMPLIFY ACROSS THE MID
WEST...SLIDING EAST. AT THE SFC...A BROAD AREA OF LOW PRESSURE IS
EXPECTED TO DEVELOP ACROSS THE CAROLINAS AS A SFC FRONT STALLS OVER
THE REGION. FORECAST SOUNDINGS INDICATE THAT MOISTURE WILL SURGE
ACROSS THE REGION...WITH PW VALUES OVER 2 INCHES BY THE AFTERNOON.
THE MOISTURE COMBINED WITH WELL ABOVE AVERAGE HIGH TEMPERATURES
SHOULD YIELD WIDESPREAD MODERATE VALUES OF CAPE. GIVEN THE BROAD
AREA OF LLVL MOISTURE CONVERGENCE...INSTABILITY...AND INCREASING MID
LEVEL FORCING...TSRA COVERAGE WILL INCREASE SIGNIFICANTLY FROM
THURSDAY. I WILL FORECAST LIKELY POPS ACROSS THE MTNS WITH VALUES IN
THE 40 TO 50 RANGE EAST.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...SIGNIFICANT PATTERN CHANGE WILL SETTLE OVER
THE REGION THIS WEEKEND AND SHOULD REMAIN THROUGH THE EXTENDED
PERIOD. MODELS INDICATE THAT THE AXIS OF A L/W TROUGH WILL SWEEP
ACROSS THE REGION THIS WEEKEND...WITH A SECONDARY WAVE EXPECTED TO
CROSS THE APPALACHIANS ON TUESDAY. AT THE SFC...THE CENTER OF A
DEEPENING LOW WILL MOVE FROM THE OHIO RIVER VALLEY ON SATURDAY TO
SOUTHERN NY BY SUNDAY EVENING. A COLD FRONT SHOULD PUSH ACROSS THE
REGION LATE SATURDAY AFTERNOON AND EVENING. THE ENVIRONMENT AHEAD OF
THE FRONT WILL FEATURE WIDESPREAD INSTABILITY AND WEAK
SHEAR...POSSIBLY SUPPORTING A BAND OF TSRA SAT AFTERNOON. I WILL
FORECAST CATE COVERAGE NEAR THE TN LINE...WITH GENERALLY LIKELY POPS
ACROSS THE REST OF THE CWA. DRIER AIR WILL BUILD ACROSS THE REGION
ON SUNDAY...RESULTING IN FALLING POP VALUES. I WILL FORECAST
PRIMARILY DIURNAL POPS ACROSS THE REGION MON AND TUES. TEMPERATURES
THROUGH THE EXTENDED ARE FORECAST TO RANGE FROM BELOW NORMAL THIS
WEEKEND TO NEAR NORMAL BY TUESDAY.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...EXPECT MAINLY LIGHT SW TO WSW FLOW EARLY THIS MORNING AS A
WEAK FRONT SAGS SOUTH TOWARD THE TERMINAL...WITH FLOW TOGGLING NW
AND THEN NE TODAY BEHIND THE BOUNDARY. PRECIPITATION CHANCES LOOK
RATHER SMALL AROUND THE AIRFIELD GIVEN THE WARM PROFILES ALOFT...BUT
ANY CONVECTION THAT FORMS WILL BE STRONG. VFR CONDITIONS WILL
CONTINUE WITH HIGH BASED CUMULUS FORMING AND BEING TOPPED BY TEMPO
HIGH CLOUD DEBRIS CIGS FROM TIME TO TIME.
ELSEWHERE...CONVECTIVE CHANCES REMAIN GREATEST AT KAVL THIS AFTN DUE
TO TERRAIN FLOW AND LOW LEVEL CONVERGENCE...BUT A TSRA CANNOT BE
RULED OUT ACROSS THE UPSTATE SITES WHERE INSTABILITY WILL BE THE
GREATEST. ANY TSRA WOULD BE QUITE STRONG WITH THE POTENTIAL FOR
GUSTY WINDS GIVEN THE MID LEVEL DRY AIR. EXPECT SFC WINDS TO TOGGLE
NW THEN NE THROUGH THE DAY BEFORE TURNING AROUND THE DIAL TO SE
LATE. THE BEST CHANCE FOR DAYBREAK RESTRICTIONS WILL BE IN THE MTN
VALLEYS...BUT WILL CONFINE THE FOG TO MVFR AT KAVL FOR NOW.
OUTLOOK...SCT DIURNAL TSTM CHANCES WILL INCREASE LATE WEEK INTO THE
WEEKEND AS A FRONT EVENTUALLY APPROACHES FROM THE NW. MORNING
RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY
WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND IN THE MOUNTAIN RIVER
VALLEYS.
CONFIDENCE TABLE...
09-15Z 15-21Z 21-03Z 03-06Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 88% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 91% HIGH 100% HIGH 100% HIGH 100%
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
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE
VALUES WERE LAST REACHED.
WEDNESDAY JUNE 24...
AVL 94 1952
CLT 102 1930
GSP 100 1952
THURSDAY JUNE 25...
AVL 96 1952
CLT 102 1914
GSP 101 1952
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...NED
NEAR TERM...HG/WJM
SHORT TERM...NED
LONG TERM...NED
AVIATION...HG
CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
307 AM EDT WED JUN 24 2015
.SYNOPSIS...
STRONG MID LEVEL HIGH PRESSURE WILL PERSIST ACROSS THE REGION
THROUGH THE REMAINDER OF THE WORK WEEK...MAINTAINING WELL ABOVE
NORMAL TEMPERATURES. A BROAD UPPER LEVEL TROF WILL MOVE OVER THE
REGION OVER THE WEEKEND RETURNING TEMPERATURES TO SEASONAL LEVELS BY
SUNDAY AND INCREASING CHANCES FOR WIDESPREAD SHOWERS AND
THUNDERSTORMS. A COOLER AND DRIER PATTERN WILL TAKE SHAPE AFTER A
FRONT PASSES EARLY IN THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 250 AM EDT...THE LATEST HRRR RUNS ALLOW LINGERING EARLY
MORNING DECAYING CONVECTION TO PASS MAINLY NE OF THE AREA ALONG THE
FRONTAL BOUNDARY DROPPING SWD...AND ALSO W OF THE AREA WITH
CONVECTION FANNING OUT IN THE BETTER INSTABILITY ACROSS SRN TN AND
INTO THE DEEP SOUTH OVERNIGHT. LITTLE MORE THAN AN ISOLD TO SCT
EARLY MORNING SHRA/TSRA MENTION WILL BE NEEDED ALONG THE SPINE OF
THE SOUTHERN APPALACHIANS.
OTHERWISE...THE WEAK SURFACE FRONTAL BOUNDARY WILL STALL IN THE
FORECAST AREA TODAY AND THEN LIKELY LIFT NORTHWARD AS A WARM FRONT
TONIGHT. THE NUMERICAL MODELS HAVE SURPRISINGLY LITTLE CONVECTION
FIRING OVER THE FORECAST AREA THIS AFTN GIVEN THE BOUNDARY IN THE
REGION. THIS APPEARS TO BE DUE TO WARM PROFILES ALOFT AND NEGATIVE
AREA IN MODEL SOUNDINGS. HOWEVER...SEVERE WEATHER WILL BE A THREAT
WITH ANY TSTMS THAT FORM AS MODERATE OR BETTER CAPE LOOKS LIKELY
ALONG WITH MID LEVEL DRY AIR AND ASSOCIATED THETA E LAPSES YIELDING
SOME MEASURE OF MICROBURST POTENTIAL. THE SRN HALF WILL BE MOST AT
RISK GIVEN THE BOUNDARY LOCATION AND LIKELY SBCAPE VALUES OF 3000 TO
3500 J/KG THERE DURING PEAK HEATING.
TEMPERATURES AND ASSOCIATED HEAT INDEX VALUES WILL BE THE OTHER
ISSUE FOR THE FORECAST TODAY. BL AND 850 TEMPS LOOK COMPARABLE TO
YESTERDAY...BUT SO DOES THE POTENTIAL FOR SOME DEWPOINT MIXING IN
THE WARMEST PIEDMONT SECTIONS. PLUS...THERE COULD BE CONSIDERABLE
DEBRIS CLOUDS AROUND AT TIMES TODAY. WILL KEEP HEAT INDEX VALUES IN
THE SRN PIEDMONT AT 100 TO 104 THIS AFTN. ANTICIPATE ANOTHER VERY
MILD NIGHT WITH PRECIPITATION CHANCES STEADILY WANING WITH THE LOSS
OF HEATING.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
AS OF 245 AM WEDNESDAY...ON THURSDAY...THE H5 AND H7 RIDGE WILL
REMAIN CENTERED OVER THE DEEP SOUTH. HOWEVER...HEIGHTS SHOULD RISE
FROM THE SOUTH AS THE RIDGE CENTER DRIFTS EAST DURING THE DAY. USING
A BLEND OF PREFERRED GUIDANCE...I WILL FORECAST HIGHS AROUND 90
WITHIN THE MTN VALLEYS TO MID TO HIGH 90S ACROSS THE FOOTHILLS AND
PIEDMONT. A WEST TO EAST FRONT WILL REMAIN ACROSS THE OHIO RIVER
VALLEYS AS A SFC TROF COVERS THE FOOTHILLS AND PIEDMONT. GIVEN THE
SFC PATTERN...LLVL WINDS ARE FORECAST TO REMAIN LIGHT FROM THE WSW.
FORECAST SOUNDINGS REVEAL THAT A SIGNIFICANT LAYER OF CIN WILL
REMAIN AROUND H75...VALUES RANGING FROM 40-60 J/KG. THE LACK OF
FORCING AND LINGERING CAPPING SHOULD FAVOR LITTLE TO NO COVERAGE OF
DEEP CONVECTION ON THURSDAY. I WILL FORECAST DRY CONDITIONS EAST OF
THE MTNS...WITH SCHC OVER THE RIDGES.
ON FRIDAY...SHORT RANGE MODELS INDICATE THAT A WEAK MID LEVEL LOW
WILL LINGER NEAR THE GA/FL LINE DURING THE DAY. IN ADDITION...A
POSITIVE TILTED L/W TROF WILL BEGIN TO AMPLIFY ACROSS THE MID
WEST...SLIDING EAST. AT THE SFC...A BROAD AREA OF LOW PRESSURE IS
EXPECTED TO DEVELOP ACROSS THE CAROLINAS AS A SFC FRONT STALLS OVER
THE REGION. FORECAST SOUNDINGS INDICATE THAT MOISTURE WILL SURGE
ACROSS THE REGION...WITH PW VALUES OVER 2 INCHES BY THE AFTERNOON.
THE MOISTURE COMBINED WITH WELL ABOVE AVERAGE HIGH TEMPERATURES
SHOULD YIELD WIDESPREAD MODERATE VALUES OF CAPE. GIVEN THE BROAD
AREA OF LLVL MOISTURE CONVERGENCE...INSTABILITY...AND INCREASING MID
LEVEL FORCING...TSRA COVERAGE WILL INCREASE SIGNIFICANTLY FROM
THURSDAY. I WILL FORECAST LIKELY POPS ACROSS THE MTNS WITH VALUES IN
THE 40 TO 50 RANGE EAST.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...SIGNIFICANT PATTERN CHANGE WILL SETTLE OVER
THE REGION THIS WEEKEND AND SHOULD REMAIN THROUGH THE EXTENDED
PERIOD. MODELS INDICATE THAT THE AXIS OF A L/W TROUGH WILL SWEEP
ACROSS THE REGION THIS WEEKEND...WITH A SECONDARY WAVE EXPECTED TO
CROSS THE APPALACHIANS ON TUESDAY. AT THE SFC...THE CENTER OF A
DEEPENING LOW WILL MOVE FROM THE OHIO RIVER VALLEY ON SATURDAY TO
SOUTHERN NY BY SUNDAY EVENING. A COLD FRONT SHOULD PUSH ACROSS THE
REGION LATE SATURDAY AFTERNOON AND EVENING. THE ENVIRONMENT AHEAD OF
THE FRONT WILL FEATURE WIDESPREAD INSTABILITY AND WEAK
SHEAR...POSSIBLY SUPPORTING A BAND OF TSRA SAT AFTERNOON. I WILL
FORECAST CATE COVERAGE NEAR THE TN LINE...WITH GENERALLY LIKELY POPS
ACROSS THE REST OF THE CWA. DRIER AIR WILL BUILD ACROSS THE REGION
ON SUNDAY...RESULTING IN FALLING POP VALUES. I WILL FORECAST
PRIMARILY DIURNAL POPS ACROSS THE REGION MON AND TUES. TEMPERATURES
THROUGH THE EXTENDED ARE FORECAST TO RANGE FROM BELOW NORMAL THIS
WEEKEND TO NEAR NORMAL BY TUESDAY.
&&
.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...EXPECT MAINLY LIGHT SW TO WSW FLOW EARLY THIS MORNING AS A
WEAK FRONT SAGS SOUTH TOWARD THE TERMINAL...WITH FLOW TOGGLING NW
AND THEN NE TODAY BEHIND THE BOUNDARY. PRECIPITATION CHANCES
CONTINUE TO LOOK SMALL AROUND THE AIRFIELD GIVEN THE WARM PROFILES
ALOFT...BUT ANY CONVECTION THAT FORMS WILL BE STRONG. VFR CONDITIONS
WILL CONTINUE WITH HIGH BASED CUMULUS FORMING AND BEING TOPPED BY
TEMPO HIGH CLOUD DEBRIS CIGS FROM TIME TO TIME.
ELSEWHERE...CONVECTIVE CHANCES REMAIN GREATEST AT KAVL THIS AFTN DUE
TO TERRAIN FLOW AND LOW LEVEL CONVERGENCE...BUT A TSRA CANNOT BE
RULED OUT ACROSS THE UPSTATE SITES WHERE INSTABILITY WILL BECOME THE
GREATEST. ANY TSRA WOULD BE QUITE STRONG WITH THE POTENTIAL FOR
GUSTY WINDS GIVEN THE MID LEVEL DRY AIR. EXPECT SFC WINDS TO TOGGLE
NW THEN NE THROUGH THE DAY BEFORE TURNING AROUND THE DIAL TO SE
LATE. THE BEST CHANCE FOR DAYBREAK RESTRICTIONS WILL BE IN THE MTN
VALLEYS...BUT WILL CONFINE THE FOG TO MVFR AT KAVL FOR NOW.
OUTLOOK...SCT DIURNAL TSTM CHANCES WILL INCREASE LATE WEEK INTO THE
WEEKEND AS A FRONT EVENTUALLY APPROACHES FROM THE NW. MORNING
RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY
WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND IN THE MOUNTAIN RIVER
VALLEYS.
CONFIDENCE TABLE...
07-13Z 13-19Z 19-01Z 01-06Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 96% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 95% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 93% HIGH 100% HIGH 100% HIGH 100%
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
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE
VALUES WERE LAST REACHED.
WEDNESDAY JUNE 24...
AVL 94 1952
CLT 102 1930
GSP 100 1952
THURSDAY JUNE 25...
AVL 96 1952
CLT 102 1914
GSP 101 1952
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...LEV/NED
NEAR TERM...HG/WJM
SHORT TERM...NED
LONG TERM...NED
AVIATION...HG
CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
229 AM EDT WED JUN 24 2015
.SYNOPSIS...
STRONG MID LEVEL HIGH PRESSURE WILL PERSIST ACROSS THE REGION
THROUGH THE REMAINDER OF THE WORK WEEK...MAINTAINING WELL ABOVE
NORMAL TEMPERATURES. A BROAD UPPER LEVEL TROF WILL MOVE OVER THE
REGION OVER THE WEEKEND RETURNING TEMPERATURES TO SEASONAL LEVELS BY
SUNDAY AND INCREASING CHANCES FOR WIDESPREAD SHOWERS AND
THUNDERSTORMS. A COOLER AND DRIER PATTERN WILL TAKE SHAPE AFTER A
FRONT PASSES EARLY IN THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 210 AM EDT...THE LATEST HRRR RUNS ALLOW CONVECTION TO PASS
MAINLY NE OF THE AREA ALONG THE FRONTAL BOUNDARY DROPPING SWD...AND
ALSO W OF THE AREA WITH CONVECTION FANNING OUT IN THE BETTER
INSTABILITY ACROSS SRN TN AND INTO THE DEEP SOUTH OVERNIGHT. LITTLE
MORE THAN AN ISOLD TO SCT EARLY MORNING SHRA/TSRA MENTION WILL BE
NEEDED ALONG THE SPINE OF THE SOUTHERN APPALACHIANS.
OTHERWISE...A SURFACE FRONTAL BOUNDARY WILL STALL IN THE FORECAST
AREA TODAY AND THEN LIKELY LIFT NORTHWARD AS A WARM FRONT TONIGHT.
THE NUMERICAL MODELS HAVE SURPRISINGLY LITTLE CONVECTION FIRING OVER
THE FORECAST AREA THIS AFTN GIVEN THE BOUNDARY IN THE REGION. THIS
APPEARS TO BE DUE TO WARM PROFILES ALOFT AND NEGATIVE AREA IN MODEL
SOUNDINGS. HOWEVER...SEVERE WEATHER WILL BE A THREAT WITH ANY TSTMS
THAT FORM AS MODERATE OR BETTER CAPE LOOKS LIKELY ALONG WITH SOME
MID LEVEL DRY AIR AND ASSOCIATED THETA E LAPSES YIELDING SOME
MICROBURST POTENTIAL. THE SRN HALF WILL BE MOST AT RISK GIVEN THE
BOUNDARY LOCATION AND LIKELY SBCAPE VALUES OF 3000 TO 3500 J/KG
THERE DURING PEAK HEATING.
TEMPERATURES AND ASSOCIATED HEAT INDEX VALUES WILL BE THE OTHER
ISSUE FOR THE FORECAST TODAY. BL AND 850 TEMPS LOOK COMPARABLE TO
YESTERDAY...BUT SO DOES THE POTENTIAL FOR SOME DEWPOINT MIXING IN
THE WARMEST PIEDMONT SECTIONS. PLUS...THERE COULD BE CONSIDERABLE
DEBRIS CLOUDS AROUND AT TIMES TODAY. WILL KEEP HEAT INDEX VALUES IN
THE SRN PIEDMONT AT 100 TO 104 THIS AFTN. ANTICIPATE ANOTHER VERY
MILD NIGHT WITH PRECIPITATION CHANCES STEADILY WANING WITH THE LOSS
OF HEATING.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
AS OF 205 PM TUESDAY...SOME SUBTLE CHANGES OCCUR BY THE END OF THE
SHORT TERM PERIOD WHICH WILL PORTEND AN EVENTUAL END TO THE
ABNORMALLY HOT CONDITIONS THAT HAVE PREVAILED. HOWEVER PRIOR TO
THAT...THE UPPER HIGH OVER THE TN VALLEY WILL CONTINUE TO NOSE
EASTWARD INTO THE SOUTHERN APPALACHIANS AND WESTERN CAROLINAS WED
NIGHT AND THEN SLOWLY WEAKEN AS IT SLIDES EASTWARD TO THE COAST BY
EARLY FRIDAY. THIS IS IN REPONSE TO A SHORT WAVE TROUGH DIGGING SE
INTO THE MIDWEST WHICH WILL BEGIN LOWERING HEIGHTS ACROSS THE SE
STATES DURING FRIDAY.
AT THE SURFACE...THE WEAK FRONTAL BOUNDARY IS FORECAST TO LIE FROM
NEAR CLT...SW THROUGH GREENVILLE INTO NE GA WEDNESDAY EVENING. BOTH
THE NAM AND GFS USE THIS BOUNDARY TO FIRE UP SOME WED EVENING
CONVECTION. HENCE...WILL NEED TO ADDRESS THIS POSSIBILITY WITH SOME
SCT TYPE POPS. BOTH THE NAM AND GFS ARE IN AGREEMENT THAT CONVECTIVE
CHANCES WILL BE SUPRESSED ON THURSDAY AS THE WEAKENING UPPER HIGH
SLIDES EAST INTO THE AREA. THE SYNOPTIC SUBSIDENCE ASSOCIATED WITH
THE UPPER HIGH SHOULD SERVE TO LIMIT CONVECTION TO THE MOUNTAINS AND
THAT MAY BE JUST ALONG THE BLUE RIDGE WHERE BEST DIFFERENTIAL
HEATING SETS UP. MODEL SOUNDINGS INDICATE CONSIDERABLE CINH TO
OVERCOME SO WILL LIMIT POPS TO WIDELY SCT OVER THE MOUNTAINS. IT
WILL REMAIN QUITE HOT ON THURSDAY AND WILL TREND MAX TEMPERATURES
TOWARD THE UPPER RANGE OF GUIDANCE WHICH MEANS MID TO UPPER 90S
OUTSIDE THE MOUNTAINS.
ON FRIDAY AS HEIGHTS BEGIN TO LOWER...WE SHOULD SEE A NOTABLE UPTICK
IN CONVECTIVE COVERAGE. THEREFORE...WILL FEATURE SCT-NUMEROUS TYPE
POPS WITH THE BEST COVERAGE OVER THE MOUNTAINS AND WESTERN AREAS.
THE INCREASED CONVECTIVE COVERAGE SHOULD SERVE TO KEEP MAXIMUM
TEMPERATURES IN CHECK SOMEWHAT. HOWEVER...IT WILL STILL BE QUITE
WARM WITH THE HOTTEST TEMPS OVER THE I-77 CORRIDOR WHERE MID 90S ARE
IN THE FORECAST.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 230 PM TUESDAY...THE BEGINNING OF THE MEDIUM RANGE FEATURES A
PRONOUNCED TRANSITION IN THE SYNOPTIC PATTERN OVER THE CONUS. AN H5
TROUGH WILL DIG DEEP INTO THE SOUTHEAST ON SATURDAY...WITH A TRAIL
OF SURFACE LOWS ROUNDING THE BASE OF THE TROUGH AND TRACKING THROUGH
THE OHIO RIVER VALLEY. A FRONTAL BOUNDARY ASSOCIATED WITH A CLOSED
SURFACE LOW ON THAT TRACK WILL APPROACH THE FORECAST AREA SATURDAY
AND EARLY SUNDAY...BRINGING LIKELY POPS TO THE ENTIRE CWA. THE FRONT
WILL PASS THE AREA BY LATE SUNDAY. THERE IS SOME DISCREPANCY IN THE
AMOUNT OF CLEARING BEHIND THE FRONT...WITH THE ECMWF MAINTAINING
MORE MOISTURE AFTER THE FRONTAL PASSAGE THAN THE DRY GFS. THE
PATTERN DOES LOOK TO DRY OUT SOMEWHAT MONDAY AND TUESDAY AS A
SURFACE HIGH BUILDS OVER THE SOUTHEAST...WITH POPS PEAKING DIURNALLY
YET REMAINING JUST BELOW CLIMO THROUGH THE END OF THE EXTENDED
PERIOD.
THE EXTENDED PERIOD WILL BEGIN WITH MAX TEMPS JUST ABOVE CLIMO...AND
WILL TAPER TO NEAR AVEAGE OVER THE WEEKEND. TEMPS WILL BE A CATEGORY
OR TWO COOLER THAN THE SHORT TERM ON MONDAY AND TUESDAY AFTER THE
FRONTAL PASSAGE.
&&
.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...EXPECT MAINLY LIGHT SW TO WSW FLOW EARLY THIS MORNING AS A
WEAK FRONT SAGS SOUTH INTO THE REGION...WITH FLOW TOGGLING NW AND
THEN NE TODAY BEHIND THE BOUNDARY. PRECIPITATION CHANCES CONTINUE TO
LOOK SMALL AROUND THE AIRFIELD GIVEN THE WARM PROFILES ALOFT...BUT
ANY CONVECTION THAT FORMS WILL BE STRONG. VFR CONDITIONS WILL
CONTINUE WITH HIGH BASED CUMULUS FORMING AND BEING TOPPED BY TEMPO
HIGH CLOUD DEBRIS CIGS FROM TIME TO TIME.
ELSEWHERE...CONVECTIVE CHANCES REMAIN GREATEST AT KAVL THIS AFTN DUE
TO TERRAIN FLOW AND LOW LEVEL CONVERGENCE...BUT A TSRA CANNOT BE
RULED OUT ACROSS THE UPSTATE SITES WHERE INSTABILITY WILL BECOME THE
GREATEST. ANY TSRA WOULD BE QUITE STRONG WITH THE POTENTIAL FOR
GUSTY WINDS GIVEN THE MID LEVEL DRY AIR. EXPECT SFC WINDS TO TOGGLE
NW THEN NE THROUGH THE DAY BEFORE TURNING AROUND THE DIAL TO SE
LATE. THE BEST CHANCE FOR DAYBREAK RESTRICTIONS WILL BE IN THE MTN
VALLEYS...BUT WILL CONFINE IT TO MVFR AT KAVL FOR NOW.
OUTLOOK...SCT DIURNAL TSTM CHANCES WILL INCREASE LATE WEEK INTO THE
WEEKEND AS A FRONT EVENTUALLY APPROACHES FROM THE NW. MORNING
RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY
WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND IN THE MOUNTAIN RIVER
VALLEYS.
CONFIDENCE TABLE...
06-12Z 12-18Z 18-24Z 00-06Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 91% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 94% HIGH 100% HIGH 100% HIGH 100%
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
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE
VALUES WERE LAST REACHED.
WEDNESDAY JUNE 24...
AVL 94 1952
CLT 102 1930
GSP 100 1952
THURSDAY JUNE 25...
AVL 96 1952
CLT 102 1914
GSP 101 1952
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...LEV
NEAR TERM...HG/WJM
SHORT TERM...LG
LONG TERM...JP/LEV
AVIATION...HG
CLIMATE...
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
948 PM CDT THU JUN 25 2015
.UPDATE...
A WARM AND MUGGY EVENING ACROSS THE MIDSOUTH...WITH FAIR WEATHER
PREVAILING NEAR THE CENTER OF OF A 592DM 500MB RIDGE. TO THE
NORTH... AN MCS WAS RIDING THE PERIPHERY OF THE RIDGE ALONG THE
I-70 CORRIDOR.
THE 01Z HRRR MODEL APPEARED A LITTLE TOO QUICK IN GENERATING AND
ACCELERATING A COLD POOL DIRECTLY SOUTH FROM THE CENTRAL MO MCS.
REGARDLESS...OUTFLOW FROM THE CURRENT ACTIVITY ENTERING SOUTH
CENTRAL MO WILL LIKELY ENTER NORTHEAST AR AND THE MO BOOTHEEL
DURING THE EARLY OVERNIGHT. IT/S UNKNOWN IF THIS OUTFLOW WILL
GENERATE NEW CONVECTION AT IT MOVES SOUTH UNDER THE MIDLEVEL
RIDGE. MUCH WILL DEPEND ON IF THE COLD POOL CAN ORGANIZE AND
ACCELERATE SOUTHWARD AT THE RATE THE HRRR SUGGESTS.
FOR THE LATE EVENING UPDATE...HAVE INTRODUCED SLIGHT CHANCE POPS
FROM NORTHEAST AR THROUGH NORTHWEST LATE TONIGHT.
PWB
&&
.PREV DISCUSSION... /ISSUED 624 PM CDT THU JUN 25 2015/
DISCUSSION...
UPDATED FOR 00Z AVIATION DISCUSSION.
PREV DISCUSSION... /ISSUED 256 PM CDT THU JUN 25 2015/
DISCUSSION...
SKIES REMAIN MOSTLY SUNNY OVER MUCH OF THE FORECAST AREA THIS
AFTERNOON WITH TEMPERATURES IN THE LOW TO MID 90S. TEMPERATURES
ARE ACTUALLY RUNNING A COUPLE OF DEGREES COOLER THAN YESTERDAY AND
HEAT INDEX VALUE ARE ALSO NOT QUITE AS HIGH AS WELL. SOME LOCATIONS
ALREADY HAVE HAD HEAT INDEX READINGS ABOVE 105 AND WITH A COUPLE
MORE HOURS OF HEATING LEFT SOME OTHER AREAS MAY ALSO REACH ABOVE
105. WILL LET HEAT ADVISORY CONTINUE THROUGH 7 PM CDT. CURRENT
RADAR SHOWS VERY LITTLE IF ANY THUNDERSTORM ACTIVITY OVER THE
FORECAST AREA SO IT APPEARS THAT MOST AREAS SHOULD REMAIN DRY
TONIGHT.
CURRENTLY A NEARLY STATIONARY BOUNDARY EXTENDS ACROSS THE CENTRAL
PLAINS THROUGH THE OHIO VALLEY AND INTO THE MID-ATLANTIC STATES.
THIS FRONT WILL START TO MOVE SOUTH AS A COLD FRONT ON FRIDAY.
THUNDERSTORMS ARE EXPECTED TO DEVELOP AHEAD OF THE FRONT AND SOME
OF THESE THUNDERSTORMS SHOULD MOVE INTO THE FORECAST AREA. THERE
IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
NORTHEAST ARKANSAS...THE MISSOURI BOOTHEEL AND NORTHWEST TENNESSEE
WITH DAMAGING WINDS AND LARGE HAIL AS THE MAIN THREATS.
TEMPERATURES WILL BE A LITTLE COOLER WITH THE INCREASE IN CLOUDS
AHEAD OF THE FRONT AS HIGHS WILL BE MAINLY IN THE LOWER 90S. HEAT
INDEX VALUES WILL NOT BE AS HIGH AS THEY HAVE BEEN THE LAST COUPLE
OF DAYS SO A HEAT ADVISORY WILL NOT BE NEEDED.
THE COLD FRONT WILL CONTINUE TO MOVE SOUTH AND WILL REACH NORTHERN
SECTIONS OF THE FORECAST AREA FRIDAY NIGHT SO THERE WILL BE A
BETTER CHANCE OF THUNDERSTORMS. THE SLIGHT RISK OF SEVERE
THUNDERSTORMS WILL CONTINUE OVER NORTHERN SECTIONS OF THE FORECAST
AREA AS WELL. TEMPERATURES WILL NOT BE AS WARM AS THEY BEEN THE
LAST FEW DAYS WITH LOWS SATURDAY MORNING IN THE UPPER 60S TO LOWER
70S.
THE COLD FRONT WILL EXIT THE FORECAST AREA SATURDAY MORNING WITH
THUNDERSTORMS ENDING OVER NORTH MISSISSIPPI. MUCH COOLER AND DRIER
AIR WILL MOVE INTO THE REGION BEHIND THE FRONT WITH HIGHS ON
SATURDAY ONLY IN THE LOW TO MID 80S. HIGH PRESSURE WILL BUILD INTO
THE REGION SATURDAY NIGHT WITH LOWS SUNDAY MORNING MAINLY IN THE
60S. DRY WEATHER AND BELOW NORMAL TEMPERATURES WILL CONTINUE INTO
SUNDAY.
BY SUNDAY NIGHT...ANOTHER COLD FRONT WILL START TO MOVE INTO THE
CENTRAL PLAINS AND THE MID MISSISSIPPI VALLEY. SOME ISOLATED
THUNDERSTORMS MAY BE POSSIBLE OVER EXTREME NORTHWEST SECTIONS OF
THE FORECAST AREA. BY MONDAY...THE COLD FRONT WILL CONTINUE TO
MOVE SLOWLY SOUTH TOWARD THE FORECAST AREA. AS IT DOES THERE WILL
BE A LITTLE BETTER CHANCE OF THUNDERSTORMS. TEMPERATURES WILL
CONTINUE TO BE BELOW NORMAL WITH HIGHS IN THE MID 80S.
THE COLD FRONT WILL START TO STALL OUT ALONG THE NORTHERN BORDER
OF THE FORECAST AREA SO THERE WILL STILL BE SCATTERED THUNDERSTORMS
FOR TUESDAY THROUGH NEXT THURSDAY. TEMPERATURES WILL CONTINUE TO
BE BELOW NORMAL THROUGH THE PERIOD.
ARS
&&
.AVIATION...
00Z TAF CYCLE (26/00Z-26/24Z)
VFR THIS PERIOD...WITH THE EXCEPTION FOR TEMPO STORMS AT JBR
LATE. OTHER SITES EXPECTING CONVECTIVE ACTIVITY NEARBY WITH
IMPACTS ON SITE JUST BEYOND THE PERIOD. LIGHT SOUTHWEST WINDS
TONIGHT WILL INCREASE TO 8-10 KTS...WITH OCCASIONAL HIGHER GUSTS.
JAB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
1154 PM CDT TUE JUN 23 2015
.UPDATE...FOR 06Z AVIATION DISCUSSION.
&&
.AVIATION UPDATE...06Z AVIATION DISCUSSION.
SFC FRONT IS EXPECTED TO MOVE S OF MID STATE BY 24/12Z...WHICH WILL USHER IN
SOME DRIER AIR TO THE AREA. WITH CONVECTION THIS EVENING NOW HAVING MOVED
S OF TERMINALS..SOME MVFR FOG INDUCED VSBYS/CEILINGS POSSIBLE CKV/BNA AROUND
24/06Z-24/15Z PER SUITABLE DEWPOINT DEPRESSIONS AND FROM RAINFALL FROM THIS
EVENING`S CONVECTION ALONG WITH LOW LEVEL MOISTURE POOLING POTENTIAL AND
SLOWLY CLRING SKIES APPROACHING 24/12Z. WITH DRIER AIR WORKING INTO MID
STATE THRU 25/06Z...BELIEVE POTENTIAL FOR ISO SHWRS/TSTMS WILL BE OVERALL
LESS THAN THIS AFTERNOON`S COVERAGE AND WILL MENTION ONLY SCT CU...SCT/BKN
AC...AND SCT/BKN CI THRU 25/02Z...WITH BKN CI THRU 25/06Z.
&&
.PREV DISCUSSION... /ISSUED 939 PM CDT TUE JUN 23 2015/
UPDATE...
18Z GFS RUN SHOWING UPPER HIGH OVER EASTERN OK WITH THE RIDGE AXIS
EXTENDING ESE ACROSS NRN AL. CURVATURE AND SHEAR NOTED UPSTREAM
WITH VORT MAX NOW MOVING THROUGH NRN MIDDLE TN. PVA IS CURRENTLY
ACROSS SOUTHERN MIDDLE TN AND IS COUPLING WITH DIVERGENCE
ALOFT...JUST NORTH OF THE RIDGE AXIS. MEAN 700-500MB FLOW IS
RATHER WEAK AND THUS STORMS ARE SLOW MOVERS. PWATS ARE STILL
RATHER HIGH AND ISOL AREAS OF FLOODING IS ONGOING.
FOR THE UPDATE...WILL INCREASE POPS ACROSS SOUTHWESTERN AREAS AND
THE SOUTHERN AND CENTRAL PLATEAU...PER ONGOING CONVECTION. WILL
ALSO MAKE A SLIGHT UPWARD TWEAK WITH THE SKY GRIDS.
PREV DISCUSSION... /ISSUED 801 PM CDT TUE JUN 23 2015/
UPDATE...
WILL ISSUE A QUICK UPDATE AND INCREASE POPS INTO THE CHANCE
CATEGORY AREA WIDE BETWEEN NOW AND 03Z. ALSO...WILL INCLUDE FOG
ACROSS THE PLATEAU FOR THE AFT MIDNIGHT PERIOD.
WILL ALLOW THE SLIGHT CHANCE TO COVER THE PRECIP CHANCES FROM 03Z
TO 06Z. THE FRONT IS APPROACHING THE KY/TN BORDER AT THIS TIME. IT
IS QUITE WEAK AND THE UPPER RIDGING BUILDING IN FROM THE WEST IS
STRENGTHENING. THEREFORE...THIS ACTIVITY SHOULD DIE OUT AS THE
NIGHT PROGRESSES. HRRR AND ISC BOTH CONCUR.
UPDATE OUT SHORTLY.
PREV DISCUSSION... /ISSUED 703 PM CDT TUE JUN 23 2015/
UPDATE...FOR 00Z AVIATION DISCUSSION.
AVIATION UPDATE...00Z AVIATION DISCUSSION.
SFC FRONT IS EXPECTED TO MOVE S OF MID STATE BY 24/12Z...WHICH WILL USHER IN
SOME DRIER AIR TO THE AREA. WITH CONVECTION THIS EVENING NOW HAVING MOVED
S OF TERMINALS..SOME MVFR FOG INDUCED VSBYS/CEILINGS POSSIBLE CKV/BNA AROUND
24/06Z-24/15Z PER SUITABLE DEWPOINT DEPRESSIONS AND FROM RAINFALL FROM THIS
EVENING`S CONVECTION ALONG WITH LOW LEVEL MOISTURE POOLING POTENTIAL AND
SLOWLY CLRING SKIES APPROACHING 24/12Z. WITH DRIER AIR WORKING INTO MID
STATE THRU 25/06Z...BELIEVE POTENTIAL FOR ISO SHWRS/TSTMS WILL BE OVERALL
LESS THAN THIS AFTERNOON`S COVERAGE AND WILL MENTION ONLY SCT CU...SCT/BKN
AC...AND SCT/BKN CI THRU 25/02Z...WITH BKN CI THRU 25/06Z.
PREV DISCUSSION.../ISSUED 404 PM CDT TUE JUN 23 2015/
DISCUSSION...
TEMPS AND DEWPOINTS SOARING AGAIN THIS AFTERNOON...HEAT INDICES
WILL BE BETWEEN 100 AND 104 TODAY. A FEW STORMS HAVE BEEN MOVING
ACROSS NORTHERN KENTUCKY THIS AFTERNOON AHEAD OF A COLD FRONT
SLOWLY MAKING ITS WAY THROUGH THE OHIO VALLEY. MODELS INDICATE IT
WILL MAKE IT FAR ENOUGH SOUTH THIS EVENING TO BRING A FEW ISOLATED
SHOWERS AND THUNDERSTORMS TO MIDDLE TENNESSEE...WITH THE BEST
CHANCE FOR PRECIP IN THE NORTHEAST COUNTIES. SOME STORMS MAY
BECOME STRONG WITH GUSTY WINDS AND HEAVY RAIN. WINDS WILL SHIFT
OUT OF THE NORTH OVERNIGHT TONIGHT BRINGING IN SLIGHTLY DRIER
AIR...WHICH LOOKS TO KEEP OUR DEWPOINTS LOW ENOUGH ON WEDNESDAY TO
ALLOW US TO ONCE AGAIN AVOID A HEAT ADVISORY. HOWEVER, THE HEAT
INDICES ARE STILL EXPECTED TO BE IN THE 100 TO 105 RANGE FOR OUR
SOUTHERN COUNTIES...SO WE`LL CONTINUE TO KEEP AN EYE ON DEWPOINTS
AND TEMPS THROUGHOUT THE DAY IN THAT AREA. WITH WEDNESDAY`S DRIER
AIR COMES LOWER POPS WITH ONLY AN AFTERNOON THUNDERSTORM OR TWO
EXPECTED.
DEWPOINTS RECOVER ON THURSDAY AS A SURFACE HIGH PASSES NORTHEAST
OF THE TENNESSEE VALLEY STIRRING UP A LIGHT SOUTHERLY FLOW AND AN
INCREASE IN MOISTURE OVER MIDDLE TENNESSEE. CONSEQUENTLY EXPECT A
FEW MORE SHOWERS AND THUNDERSTORMS THURSDAY AFTERNOON AND EVENING
ALONG WITH HEAT INDICES AROUND ADVISORY CRITERIA...105 TO 108.
WILL HOLD OFF ON ISSUING AN ADVISORY AT THIS TIME UNTIL CONFIDENCE
IS HIGHER.
PRECIP CHANCES INCREASE AS WE HEAD INTO FRIDAY. AN UPPER TROUGH
WILL DEEPEN OVER THE EASTERN U.S. AND SWING A COLD FRONT THROUGH
THE TENNESSEE VALLEY EARLY SATURDAY MORNING. THIS WILL ALLOW FOR
A GOOD FOCUSING MECHANISM FOR THUNDERSTORM DEVELOPMENT. FRIDAY
AFTERNOON INSTABILITY IS HIGH ENOUGH FOR THUNDERSTORM
DEVELOPMENT...HOWEVER THE FRONT WILL BE LOCATED TO THE NORTH OF
THE CWA DURING THIS TIME...SO ANY STORMS WILL LIKELY SPARK DUE TO
AFTERNOON HEATING. ALONG WITH THE LACK OF A FOCUSING
MECHANISM...ORGANIZATION MAY BE LIMITED BY BULK SHEAR VALUES
LESS THAN 30KTS...HOWEVER SOME SEVERE STORMS WILL STILL BE
POSSIBLE WITH THE AMOUNT OF INSTABILITY IN PLACE. PWATS ARE
IMPRESSIVE DURING THIS TIME FRAME WITH VALUES OF 1.9 TO 2.00
INCHES STILL INDICATED ON BOTH THE NAM AND THE GFS...SO EXPECTING
STRONG...POSSIBLY SEVERE STORMS WITH HEAVY RAINFALL FRIDAY
AFTERNOON AND EVENING.
AS THE FRONT APPROACHES ON SATURDAY MORNING BULK SHEAR VALUES
INCREASE TO AROUND 40KTS. COULD SEE A SPIKE IN THUNDERSTORM
ACTIVITY EARLY SATURDAY MORNING ALONG THE FRONTAL BOUNDARY THEN
COOLER TEMPS DURING THE AFTERNOON WITH MOSTLY CLOUDY SKIES BEHIND
THE FRONT. CONDITIONS DRY OUT GOING INTO SUNDAY AS THE PREVIOUS
SYSTEM CONTINUES OFF TO THE EAST AND LEAVES THE MID STATE WITH
MUCH MORE PLEASANT DEWPOINTS AND HIGH TEMPERATURES. SUNDAY LOOKS
TO BE A GREAT DAY TO GET OUTSIDE AND ENJOY TEMPERATURES AROUND 80
WITH DEWPOINTS IN THE LOW 60S. TEMPERATURES GRADUALLY WARM DURING
THE FIRST HALF OF THE WORK WEEK NEXT WEEK AS A WEAK SURFACE HIGH
MOVES ACROSS THE TENNESSEE VALLEY. A CHANCE OF THUNDERSTORMS
CREEPS INTO THE FORECAST BY TUESDAY.
PREV DISCUSSION... /ISSUED 108 PM CDT TUE JUN 23 2015/
AVIATION UPDATE...
SURFACE FRONT JUST NORTH OF THE OHIO RIVER WILL MOVE SOUTHWARD AS
WE GO THROUGH THE AFTERNOON AND INTO TONIGHT. AM LOOKING FOR A LINE
OF CONVECTION TO FIRE OFF ALONG THE OHIO RIVER 20Z-21Z TIME FRAME
AND SINK SOUTHWARD WITH THE LEADING EDGE ALONG THE TENNESSEE/KENTUCKY
BORDER AROUND 00Z AND CONTINUE SOUTHWARD INTO MIDDLE TENNESSEE DURING
THE EVENING. FOR NOW WILL RUN VICINITY THUNDERSTORMS AT TERMINALS
BUT WILL UPDATE ONCE LINE DEVELOPS AND TRY AND TIME IT A LITTLE
BETTER. ALSO...LOOKING FOR SOME LATE NIGHT FOG.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 74 92 73 96 / 30 20 10 20
CLARKSVILLE 72 89 72 94 / 30 20 10 10
CROSSVILLE 70 86 68 90 / 40 20 10 20
COLUMBIA 74 93 73 97 / 30 20 10 20
LAWRENCEBURG 74 93 73 95 / 50 20 10 20
WAVERLY 73 91 73 95 / 30 20 10 20
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1124 PM CDT TUE JUN 23 2015
.UPDATE...
UPDATED TO ADD 06Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 1022 PM CDT TUE JUN 23 2015/
UPDATE...EVENING UPDATE
IT NOW LOOKS MORE LIKELY THAT THUNDERSTORMS WILL CONTINUE
OVERNIGHT PUSHING SOUTH ACROSS MOST IF NOT ALL OF THE MIDSOUTH.
ADJUSTED POPS ACCORDINGLY. STORMS WILL MAINLY IMPACT WEST
TENNESSEE AND NORTH MISSISSIPPI...BUT CANNOT BE RULED OUT
ANYWHERE. FREQUENT LIGHTENING AND VERY HEAVY RAINFALL CAN BE
EXPECTED. LOCALIZED FLOODING IS POSSIBLE. WIDESPREAD SEVERE
WEATHER IS NOT ANTICIPATED AT THIS TIME.
30
PREV DISCUSSION... /ISSUED 719 PM CDT TUE JUN 23 2015/
UPDATE...EVENING UPDATE.
DISCUSSION...
INCREASED POPS ACROSS WEST TENNESSEE...THE MISSOURI BOOTHEEL AND
NORTHEAST ARKANSAS. DON`T THINK THERE IS ANY REAL SEVERE THREAT
BUT LOCALLY HEAVY RAIN AND FREQUENT LIGHTNING IS LIKELY. STORMS
SHOULD DIMINISH IN BOTH INTENSITY AND COVERAGE AFTER SUNSET.
PREV DISCUSSION... /ISSUED 623 PM CDT TUE JUN 23 2015/
CURRENTLY...STRONG UPPER RIDGE EXTENDS FROM THE SOUTHERN PLAINS
INTO THE MIDSOUTH. MEANWHILE A WEAK COLD FRONT HAS PUSHED INTO
SOUTHERN MISSOURI AND WESTERN KY...JUST NORTH OF THE MIDSOUTH.
VERY WARM AIR HAS PUSHED INTO THE MIDSOUTH WITH TEMPS IN THE MID
90S ACROSS MUCH OF THE AREA. SURFACE DEWPOINTS ARE POOLING ACROSS
THE REGION...SOUTH OF THE COLD FRONT...WITH READINGS IN THE MID
TO SOMETIMES UPPER 70S. THIS IS CREATING HEAT INDEX VALUES ABOVE
105 ACROSS MUCH OF THE MIDSOUTH. HAVE EXPANDED THE HEAT ADVISORY
TO COVER MOST OF THE MIDSOUTH THIS AFTERNOON INTO WEDNESDAY.
THE HRRR HAS BEEN TRYING TO DEVELOP CONVECTION ALONG THE WEAK COLD
FRONT TO THE NORTH FOR THE LAST FEW HOURS BUT IT HAS NOT HAPPENED
YET. GIVEN THE WEAK CAP AND SBCAPES AROUND 5000 J/KG THERE IS
STILL THE POSSIBILITY OF ISOLATED STORMS DEVELOPING OVER THE NEXT
FEW HOURS.
TONIGHT...ANY CONVECTION WILL DISSIPATE BY 02Z OR SO WITH MOSTLY
CLEAR SKIES AND WARM TEMPERATURES OVERNIGHT. LOWS IN THE 70S.
WEDNESDAY...ANOTHER VERY HOT AND HUMID DAY WITH THE UPPER RIDGE
CENTERED OVER THE AREA. EXPECT HIGHS IN THE MID 90S AND DEWPOINTS
IN THE MID 70S. THE HEAT ADVISORY HAS BEEN EXTENDED THROUGH 7 PM
THURSDAY FOR MOST OF THE MIDSOUTH FOR HEAT INDICES EXCEEDING 105
DEGREES WEDNESDAY AFTERNOON. AN ISOLATED AFTERNOON STORM COULD
OCCUR ANYWHERE BUT THE BEST CHANCE WILL PROBABLY BE ACROSS NORTH
MISSISSIPPI.
THURSDAY...THE UPPER RIDGE WEAKENS A BIT ON THURSDAY BUT STILL
HOT AND HUMID. HEAT ADVISORIES MAY NEED TO BE EXTENDED. STILL VERY
WARM AIRMASS ACROSS THE REGION WITH 925MB TEMPS OF 28C ACROSS MUCH
OF THE AREA. MODELS ARE POINTING TOWARD INCREASING MOISTURE MOVING
UP FROM THE GULF WITH BETTER CHANCES OF AFTERNOON SHOWERS AND
THUNDERSTORMS ACROSS NORTH MISSISSIPPI.
FRIDAY AND SATURDAY...MAJOR PATTERN SHIFT AS THE UPPER RIDGE
BREAKS DOWN AND A DEEP UPPER TROF DEVELOPS OVER THE EASTERN U.S.
A COLD FRONT WILL PUSH THROUGH THE AREA FRIDAY INTO SATURDAY
MORNING WITH NUMEROUS SHOWERS AND THUNDERSTORMS. A FEW STRONG TO
SEVERE STORMS ARE POSSIBLE DURING THIS PERIOD. MUCH COOLER AND
DRIER WEATHER WILL SETTLE OVER THE REGION LATER SATURDAY INTO
EARLY NEXT WEEK AS THE REGION REMAINS UNDER THE INFLUENCE OF THE
UNSEASONABLE DEEP UPPER TROF.
SJM
&&
.AVIATION...
06Z TAF CYCLE
SHOWERS AND THUNDERSTORMS WILL AFFECT TUP THROUGH 24/08Z.
OTHERWISE...SHORT TERM TRENDS SUGGEST A WEAK SURFACE BOUNDARY AND
LEFTOVER OUTFLOW BOUNDARIES FROM TONIGHT/S CONVECTIVE ACTIVITY MAY
INTERACT WITH AN UNSTABLE ATMOSPHERE TO TRIGGER REDEVELOPMENT OF SHOWERS
AND THUNDERSTORMS ACROSS TAF SITES...PREDOMINANTLY AT
MKL...TUP...AND MEM MAINLY AFTER 24/17Z. TEMPORARY IFR CONDITIONS
POSSIBLE WITHIN THUNDERSTORMS. OTHERWISE...VFR CONDITIONS EXPECTED
TO PERSIST THROUGH MUCH OF THE PERIOD. LIGHT W/NW WINDS WILL VEER
N ON WEDNESDAY.
CJC
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...HEAT ADVISORY FROM NOON TO 7 PM CDT WEDNESDAY FOR CLAY-CRAIGHEAD-
CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI-
PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...HEAT ADVISORY FROM NOON TO 7 PM CDT WEDNESDAY FOR DUNKLIN-
PEMISCOT.
MS...HEAT ADVISORY FROM NOON TO 7 PM CDT WEDNESDAY FOR ALCORN-BENTON
MS-CALHOUN-CHICKASAW-COAHOMA-DESOTO-ITAWAMBA-LAFAYETTE-LEE
MS-MARSHALL-MONROE-PANOLA-PONTOTOC-PRENTISS-QUITMAN-
TALLAHATCHIE-TATE-TIPPAH-TISHOMINGO-TUNICA-UNION-YALOBUSHA.
TN...HEAT ADVISORY FROM NOON TO 7 PM CDT WEDNESDAY FOR CHESTER-
CROCKETT-DYER-FAYETTE-HARDEMAN-HARDIN-HAYWOOD-LAKE-
LAUDERDALE-MADISON-MCNAIRY-OBION-SHELBY-TIPTON.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
110 AM CDT WED JUN 24 2015
.UPDATE...
PLEASE SEE THE 06Z AVIATION DISCUSSION BELOW.
&&
.AVIATION...
LITTLE CHANGES HAVE BEEN MADE TO THE ONGOING AVIATION FORECASTS.
THE LATEST RADAR DATA DOES SHOW SOME CONVECTION ACROSS THE WESTERN
HILL COUNTRY...SOUTHERN EDWARDS PLATEAU AND RIO GRANDE PLAINS
EARLY THIS MORNING. THIS ACTIVITY IS EXPECTED TO REMAIN TOO
ISOLATED TO MENTION IN THE LATEST FORECAST. OTHERWISE...LOW CLOUDS
WILL CONTINUE TO DEVELOP OVERNIGHT...LEADING TO MVFR AND IFR
CONDITIONS THROUGH ROUGHLY 16Z. CLOUDS WILL LIFT WITH VFR EXPECTED
FOR TOMORROW AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 1124 PM CDT TUE JUN 23 2015/
UPDATE...
HAVE MADE A QUICK PRE-MORNING PACKAGE UPDATE TO THE ONGOING
FORECAST BASED ON CURRENT RADAR TRENDS AND RECENT RUNS OF THE
HRRR. THE HRRR SUGGESTS THAT THE VERY ISOLATED SHOWERS THAT ARE
CURRENTLY ONGOING FROM COMSTOCK...EAST TO HONDO...AND NORTH TO
LLANO WILL CONTINUE THROUGH THE EARLY MORNING HOURS. HAVE ADDED
SLIGHT CHANCE POPS TO THE WESTERN HILL COUNTRY...EDWARDS
PLATEAU...AND RIO GRANDE PLAINS. HAVE ALSO RETRENDED HOURLY GRIDS.
PREV DISCUSSION... /ISSUED 543 PM CDT TUE JUN 23 2015/
UPDATE... /SLIGHT ADJUSTMENT TO EVENING POPS/
SOME POPS WERE ADDED DEEPER INTO THE HILL COUNTRY TO ACCOUNT FOR
SOME SEA-BREEZE ENHANCED STREAMER CONVECTION...AND WERE RAISED TO
30 PERCENT WHERE SOME CLUSTERS HAVE FORMED OVER THE RIO GRANDE
PLAINS. RAPID REFRESH MODELS STILL SHOW A WEAKENING TREND WITH
THE LOSS OF DAYTIME HEATING...SO THE AFTERNOON FORECAST PACKAGE
REMAINS ON TRACK FOR THE REST OF TONIGHT.
PREV DISCUSSION... /ISSUED 233 PM CDT TUE JUN 23 2015/
SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...
STARTING TO SEE MORE EFFECTS FROM THE UPPER RIDGE TODAY AND THE
OVERALL COVERAGE OF SHOWERS AND THUNDERSTORMS IS LOWER. WE DO
HAVE A FEW STORMS ACROSS THE SOUTHERN COUNTIES...BUT THIS IS NOT
ACCOUNTING FOR MUCH RAINFALL. SHOULD SEE THIS ACTIVITY LINGER FOR
THE NEXT SEVERAL HOURS BEFORE DISSIPATING WITH THE LOSS OF DAYTIME
HEATING. WILL CARRY 20 POPS AFTER 00Z FOR VAL VERDE COUNTY AS
HIGH-RES MODELS ARE HINTING AT SOME ACTIVITY REMAINING CLOSER TO
THE DEPARTING UPPER LOW. TOMORROW SHOULD BE SIMILAR TO TODAY WITH
20-40 POPS ACROSS THE SOUTHERN AND SOUTHEASTERN CWA FOR ANY
ACTIVITY ASSOCIATED WITH THE AFTERNOON SEA BREEZE. HIGHS TOMORROW
WILL BE NEAR 90 DEGREES AND WITH AFTERNOON DEWPOINTS REMAINING IN
THE LOW 70S...HEAT INDICES WILL REACH THE UPPER 90S.
LONG TERM (THURSDAY THROUGH TUESDAY)...
THURSDAY SHOULD CONTINUE TO SAME FORECAST AS THE PREVIOUS COUPLE
OF DAYS. WE COULD SEE THE BEST DAY FOR SEA BREEZE ACTIVITY AS
LOW-LEVEL WINDS ARE A BIT LESS AND SHOULD PROMOTE A BIT MORE
COVERAGE OF SHOWERS AND STORMS. THE ATMOSPHERE SHOULD TEMPORARILY
DRY OUT A BIT FRIDAY AND WE SHOULD NOT SEE MUCH ACTIVITY.
THE FOCUS OF THE REMAINING FORECASTS SHIFTS TO A POSSIBLE COLD
FRONT AFFECTING THE AREA AND INCREASING RAIN CHANCES SATURDAY
NIGHT THROUGH TUESDAY. A STRONG RIDGE WILL AMPLIFY ACROSS THE
WESTERN CONUS THIS WEEKEND WITH A DEEP TROUGH ACROSS THE EASTERN
CONUS. THIS WILL ALLOW A LATE-SEASON COLD FRONT TO DIVE SOUTH AND
BEGIN TO ENTER OUR NORTHERN CWA SATURDAY NIGHT. POPS FOR NOW WILL
BE IN THE 20 TO 50 PERCENT RANGE BUT COULD BE RAISED AS
CONFIDENCE INCREASES CLOSER TO THIS WEEKEND. PRECIPITABLE WATER
VALUES WILL BE NEAR 2 INCHES AND THIS COMBINED WITH A FRONTAL
BOUNDARY AND EXPECTED SLOW STORM MOTIONS COULD LEAD TO LOCALLY
HEAVY RAINFALL. THIS WILL BE SOMETHING THAT NEEDS TO BE WATCHED
CLOSELY AS WE NEAR THE WEEKEND. THE FRONT IS EXPECTED TO LIFT
NORTH ON MONDAY AND ADDITIONAL RAIN CHANCES WILL CONTINUE THROUGH
TUESDAY WITH PLENTY OF MOISTURE LEFT OVER.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 90 72 89 73 91 / 20 10 20 10 -
AUSTIN BERGSTROM INTL AIRPORT 89 71 88 72 90 / 20 10 20 10 -
NEW BRAUNFELS MUNI AIRPORT 89 72 89 73 91 / 20 10 20 10 -
BURNET MUNI AIRPORT 88 71 89 72 91 / 10 10 10 10 -
DEL RIO INTL AIRPORT 89 73 91 73 93 / 20 10 10 10 -
GEORGETOWN MUNI AIRPORT 89 72 89 73 91 / 10 10 10 10 -
HONDO MUNI AIRPORT 88 72 89 72 90 / 20 10 20 10 -
SAN MARCOS MUNI AIRPORT 88 72 88 73 90 / 20 10 20 10 -
LA GRANGE - FAYETTE REGIONAL 90 73 89 74 90 / 30 10 40 10 10
SAN ANTONIO INTL AIRPORT 88 73 89 74 90 / 20 10 20 10 -
STINSON MUNI AIRPORT 89 73 89 73 91 / 20 10 20 10 -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...24
SYNOPTIC/GRIDS...TREADWAY
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
352 PM CDT WED JUN 24 2015
.SHORT TERM...
TONIGHT... FORECAST CONFIDENCE MEDIUM.
CONVECTION ASSOCIATED WITH THE LOW LEVEL JET /LLJ/... SHORTWAVE
ENERGY AND UPPER LEVEL DIVERGENCE OVER CENTRAL IOWA WILL CONTINUE TO
MOVE ESE THROUGH NORTHERN IL. ONLY LIGHT SHOWERS... IF ANYTHING...
ARE EXPECTED TO REACH SOUTHERN WI FROM LATE AFTERNOON THROUGH EARLY
EVENING.
THE LLJ IS EXPECTED TO INTENSIFY OVER SOUTH CENTRAL IOWA THIS
EVENING AS IT VEERS EAST. THE NOSE OF THE LLJ IS NOW EXPECTED TO
REMAIN OVER EAST CENTRAL IOWA OR SOUTH... ALONG WITH THE 850MB WARM
FRONT. THIS IS FARTHER SOUTH THAN MANY OF THE PREVIOUS MODEL RUNS.
THUNDERSTORMS ARE ANTICIPATED TO FIRE UP ALONG THE SURFACE WARM
FRONT OVER CENTRAL IOWA WITH THE INCREASING LLJ LATE THIS EVENING
PER THE HRRR AND THEN SLIDE EAST THROUGH CENTRAL IL.
KEPT CHANCE FOR SHOWERS AND THUNDERSTORMS ACROSS SOUTHERN WI DUE TO
THE VICINITY OF THE NOSE OF THE LLJ... UPPER DIVERGENCE WITH THE
RIGHT ENTRANCE REGION OF THE UPPER JET... AND WEAK VORTICITY
ADVECTION. ELEVATED INSTABILITY WILL REMAIN WEAK WITH LESS THAN 500
J/KG CAPE. NOT EXPECTING HEAVY RAIN TRAINING OVER AN AREA FOR A LONG
PERIOD OF TIME. NOT EXPECTING SEVERE WEATHER ALTHOUGH SPC HAS NOT
TRIMMED SOUTHERN WI OUT OF THE SLIGHT RISK YET THIS AFTERNOON.
.THURSDAY... FORECAST CONFIDENCE MEDIUM.
LIGHT SURFACE WINDS AND LINGERING LOW LEVEL MOISTURE SHOULD LEAD TO
LOW CLOUDS ACROSS SOUTHERN WI EARLY THURSDAY MORNING. THESE SHOULD
SLOWLY SCOUR OUT THROUGH THE DAY. LIGHT RAIN SHOWERS MAY LINGER WITH
THIS MOISTURE THROUGH THE MORNING HOURS BUT CONFIDENCE IS LOW... SO
ONLY HAVE SLIGHT CHANCE POPS IN FORECAST. AFTERNOON SHOULD BE DRY
WITH INCREASING SUNSHINE AND HIGHS BACK UP AROUND 80 EXCEPT NEAR THE
LAKE.
.LONG TERM...
.FRIDAY AND SATURDAY...
NW FLOW ALOFT WILL TURN MORE CYCLONIC AS A SHARP UPPER LEVEL TROF
DIVES SOUTH ACROSS THE REGION ON FRIDAY AND SATURDAY. HOWEVER...THE
FLOW OVER WISCONSIN DURING THIS PERIOD WILL BE WEAK...AND THERE WILL
BE LITTLE FORCING FOR ASCENT IN THE UPPER LEVELS. IN THE MID-
LEVELS...WE WILL BE ON THE COOL AND DRY SIDE OF A FRONT EXTENDING
WEST FROM THE LOW THAT WILL PASS ON THURSDAY. A SECOND LOW WILL
APPROACH THE STATE FROM THE SOUTHWEST ON FRIDAY...BUT SHOULD STAY TO
THE SOUTH OF THE STATE THANKS TO THE FRONT IN PLACE. GFS AND EURO DO
BRING SOME LIGHT PRECIP INTO THE AREA ON FRIDAY AFTERNOON...BUT
CHOSE TO REMAIN DRY AT THIS POINT GIVEN THE MEAGER ASCENT AND
MOISTURE.
BY FRIDAY EVENING...THE UPPER LEVEL TROF AXIS WILL HAVE PASSED TO
THE EAST OF THE STATE...PLACING WISCONSIN UNDER NORTHERLY FLOW
ALOFT. THE MID AND LOW LEVELS WILL DRY OUT...MAKING FOR A VERY NICE
DAY ON SATURDAY.
.SUNDAY THROUGH WEDNESDAY...
WISCONSIN WILL BE FIRMLY ENTRENCHED IN NNW FLOW ALOFT AS A DEEP
UPPER LEVEL TROF STALLS OVER THE EASTERN CONUS AND A ROBUST
RIDGE/CLOSED HIGH BUILDS INTO THE WESTERN CONUS. THIS PATTERN WILL
PERSIST THROUGH THE PERIOD AS A FEW SHORTWAVE TROFS PASS ACROSS THE
STATE REINFORCING THE TROF OVER THE EAST. THOSE SHORTWAVES WILL
PROVIDE THE LIFT FOR RAIN CHANCES EACH DAY IN THIS PERIOD. THE NW
FLOW SHOULD KEEP TEMPS SLIGHTLY BELOW NORMAL THROUGH THIS PERIOD.
&&
.AVIATION/00Z TAFS/...
VFR CONDITIONS ARE EXPECTED THROUGH LATE EVENING. A COMPLEX OF
STORMS IS THEN EXPECTED TO TRACK ACROSS CENTRAL ILLINOIS OVERNIGHT.
SOUTHERN WI SHOULD GET CLIPPED BY SHOWERS AND A FEW THUNDERSTORMS ON
THE NORTHERN SIDE OF THE MAIN AREA OF CONVECTION. MVFR CONDITIONS
CAN BE EXPECTED WITHIN ANY THUNDERSTORMS.
IFR CONDITIONS WITH CIGS/VSBYS ARE POSSIBLE LATER TONIGHT AS THE
CONVECTION MOVES OFF WHILE THE ATMOSPHERE REMAINS VERY MOIST WITHIN
A VERY WEAK LOW LEVEL FLOW. VFR EXPECTED BY THU AFTERNOON.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TONIGHT/THURSDAY AND AVIATION/MARINE...MRC
THURSDAY NIGHT THROUGH WEDNESDAY...BSH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
217 PM CDT WED JUN 24 2015
.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 217 PM CDT WED JUN 24 2015
WATER VAPOR IMAGERY AND RAP 500MB ANALYSIS THIS AFTERNOON SHOWS
WEST/NORTHWEST FLOW ACROSS THE DAKOTAS INTO THE GREAT LAKES REGION.
WITHIN THIS FLOW A COUPLE OF WEAK EMBEDDED SHORT WAVE TROUGHS WERE
ACROSS NORTHERN MN AND ACROSS EASTERN NEB/WESTERN IA. STRONG TO
SEVERE THUNDERSTORMS WERE TIED TO SHORTWAVE COMING ACROSS EASTERN
NEB/WESTERN IA WHILE THE CONVECTION ACROSS NORTHERN MN/UPPER MI WAS
TIED MORE TO CONVERGENCE OF LAKE BREEZE FRONT. OUR AREA WAS IN
BETWEEN THESE TWO SYSTEM...HIGH AND DRY FOR NOW. UNDER PARTLY CLOUDY
SKIES...TEMPERATURES RANGED FROM THE MIDDLE 70S TO THE LOWER 80S.
FOR TONIGHT...WILL SEE THAT MID-LEVEL SHORTWAVE AND MCV ACROSS IA
PASS SOUTH OF THE AREA EARLY THIS EVENING. MODELS THEN SHOW RETURN
850MB FLOW BEHIND THIS SYSTEM LATER THIS EVENING INTO THE OVERNIGHT
HOURS. THIS PUSHES A WARM FRONT THAT WAS OVER NORTHERN KS INTO
NORTHERN MO...NORTHWARD NEAR I-80. 850MB MOISTURE TRANSPORT LOOKS TO
REGENERATE A BAND OF ELEVATED SHOWERS AND THUNDERSTORMS NORTH OF THE
WARM FRONT...POSSIBLE GRAZING OUR NORTHEAST IA COUNTIES. LATEST WRF
RUNS KEEP CONVECTION JUST TO OUR SOUTH WHILE COARSER DETERMINISTIC
NAM/GFS/ECMWF MODELS SUGGESTING CONVECTION REACHING INTO NORTHEAST
IA AND SOUTHWEST WI. WILL KEEP LIKELY POPS CONFINED TO FAR SOUTHERN
FAYETTE/CLAYTON COUNTIES IN NORTHEAST IA AND FAR SOUTHER GRANT
COUNTY IN WI...TAPERING OFF RAPIDLY TO SLIGHT CHANCE POPS
ALONG/SOUTH OF I-90. HIGHER CAPE AXIS STAYS SOUTH OF THE AREA
THROUGH TONIGHT...SO NOT ANTICIPATING ANY SEVERE WEATHER IN OUR
FORECAST AREA...BUT WILL CONTINUE TO MAINTAIN A WATCHFUL EYE IN CASE
THE WARM FRONT/CAPE POOL SURGES FARTHER NORTHWARD THAN ANTICIPATED.
ALSO...WILL HAVE TO KEEP AN EYE ON THE SHOWERS/STORMS ACROSS
NORTHERN WI OVERNIGHT AS THAT WEAK MID-LEVEL TROUGH SWINGS THROUGH.
NOT MUCH WORKING FOR IT OTHER THAN STEEPER MID-LEVEL LAPSE
RATES...BUT NO SURFACE CONVERGENCE OR TRIGGER. IN FACT...MOST OF THE
WRF MODELS SHOW A WEAKENING TREND AFTER SUNSET WITH LOSS OF HEATING.
THURSDAY LOOKS FAIRLY QUIET AND COOLER THAN NORMAL AS NORTHWEST FLOW
ALOFT DOMINATES THE REGION. WITH SURFACE HIGH PRESSURE OVER LAKE
SUPERIOR PUMPING DRIER NORTHEAST FLOW INTO THE AREA...THINKING
MODELS ARE OVERDONE ON CONVECTION. LOOKS LIKE A LOT OF CUMULUS...BUT
ANY SHOWER/THUNDER SHOULD REMAIN CONFINED TO FAR NORTHERN WI/U.P. IN
STEEPER LAPSE RATES AND CLOSER TO ANY LAKE BREEZE CONVERGENCE ZONES.
OTHERWISE...LOOK FOR HIGHS GENERALLY IN THE 75-80 DEGREE RANGE.
FOR THURSDAY NIGHT...NORTHWEST FLOW DROPS ANOTHER MID-LEVEL
TROUGH/PV-ADVECTION ACROSS MN INTO IA WITH A SURFACE TROUGH IN
PLACE. THIS LOOKS TO PRODUCE A FEW SHOWERS/ISOLATED STORMS WEST OF
THE MISSISSIPPI RIVER. LOOK FOR OVERNIGHT TEMPERATURES DROPPING INTO
THE MID 50S TO THE LOWER 60S.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 217 PM CDT WED JUN 24 2015
WILL STILL SEE A SLIGHT CHANCE OF SHOWERS AND ISOLATED THUNDERSTORMS
MAINLY WEST OF THE MISSISSIPPI RIVER FRIDAY AS THE MID-LEVEL TROUGH
CONTINUES TO ROTATE SOUTHEAST ACROSS THAT AREA. OTHERWISE...PLAN ON
A PARTLY SUNNY DAY DOMINATED WITH DECENT CUMULUS FIELD WITH HIGHS
ONLY TOPPING OFF IN THE LOWER/MIDDLE 70S.
FRIDAY NIGHT THROUGH SATURDAY LOOK DRY AS A WEAK RIDGE OF HIGH
PRESSURE BUILDS INTO THE REGION. LOOK FOR HIGHS IN THE 75-80 DEGREE
RANGE.
THE REST OF THE WEEKEND INTO MID-NEXT WEEK IS DOMINATED WITH MUDDLED
NORTHWEST FLOW ALOFT WITH EMBEDDED SHORTWAVE TROUGH ENERGY. AS A
RESULT...PLAN ON PERIODIC ON/OFF SHOWER AND THUNDERSTORM CHANCES
WITH TEMPERATURES REMAINING BELOW NORMAL. LOOK FOR HIGHS IN THE
MIDDLE/UPPER 70S WITH LOWS IN THE MIDDLE 50S TO THE LOWER 60S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1215 PM CDT WED JUN 24 2015
WARM FRONT OF INTEREST FOR CONVECTION LATE THIS AFTERNOON AND
TONIGHT REMAINS IN NORTHERN MO EARLY THIS AFTERNOON. CONVECTION
EARLY THIS AFTERNOON CONFINED TO FAR EASTERN NEB AND SOUTHERN 2/3 OF
IA...MOVING STEADILY EAST. THIS CONVECTION WILL KEEP THE FRONT FROM
MOVING NORTH THRU THE AFTERNOON...WITH LITTLE MORE THAN SCT DIURNAL
CUMULUS AND GOOD VFR EXPECTED AT THE TAF SITES THRU EARLY THIS
EVENING. STILL A SHRA/TSRA CHANCE LATER THIS EVENING AND OVERNIGHT
AS A SURGE OF MOISTURE PUSHES NORTHEAST OVER THE WARM FRONT. APPEARS
THE BULK OF THIS WILL STAY SOUTH OF THE MN/IA BORDER AND LEFT TAFS
FREE OF A SHRA/TSRA MENTION TONIGHT BUT DID INCLUDE SOME 3500-4500
FT CIGS OVERNIGHT. SFC LOW PASSES ACROSS IA TONIGHT WITH DRIER
NORTHEAST TO NORTH FLOW AND GOOD VFR SPREADING ACROSS THE AREA THU.
&&
.HYDROLOGY...
ISSUED AT 217 PM CDT WED JUN 24 2015
RIVERS ARE RECEDING. SOME MINOR FLOODING REMAINS ALONG THE CEDAR
RIVER AT CHARLES CITY...BUT THE RIVER IS FORECAST TO FALL BELOW
STAGE THIS AFTERNOON. REFER TO THE LATEST FLOOD STATEMENTS FOR THE
LATEST STAGES AND FORECAST.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION.....RRS
HYDROLOGY....DAS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
346 AM CDT WED JUN 24 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 346 AM CDT WED JUN 24 2015
LATEST WATER VAPOR SATELLITE IMAGERY INDICATING WEST TO EAST ZONAL
FLOW ACROSS THE NORTHERN TIER STATES WITH SEVERAL PIECES OF
ENERGY EMBEDDED IN THE FLOW. LATEST 08Z SURFACE ANALYSIS SHOWS
SURFACE FRONT EXTENDING FROM WESTERN KANSAS INTO WESTERN KENTUCKY.
CURRENT MOSAIC RADAR INDICATES SHOWERS AND THUNDERSTORMS OVER
EASTERN NEBRASKA...CENTRAL AND WESTERN IOWA. THIS IS IN RESPONSE
TO 850-700MB MOISTURE TRANSPORT/CONVERGENCE IN ASSOCIATION WITH A
SUBTLE SHORTWAVE TROUGH OVER CENTRAL NEBRASKA.
MAIN FORECAST CONCERNS TODAY INTO TONIGHT CONTINUE TO BE PLACEMENT
OF SURFACE FRONT AND HOW FAR NORTH SURFACE FRONT MOVES TODAY.
FIRST WEAK SHORTWAVE OVER EASTERN NEBRASKA/WESTERN IOWA AND
ASSOCIATED CONVECTION IS EXPECTED TO REMAIN TO THE SOUTH OF THE
FORECAST AREA THIS MORNING. A SECOND PIECE OF ENERGY OVER WESTERN
SOUTH DAKOTA WILL QUICKLY PUSH INTO CENTRAL IOWA AROUND 18Z TODAY
AND SPREAD SCATTERED CONVECTION INTO THE FAR SOUTHERN PART OF THE
FORECAST AREA.
THEN FOCUS TURNS TO SURFACE FRONT...AS THE LATEST 24.00Z GFS/NAM
CONTINUE TO LIFT SURFACE FRONT INTO CENTRAL IOWA...AND THE 24.00Z
ECMWF SUGGEST FRONT WILL REMAIN OVER IOWA/MISSOURI BORDER THIS
AFTERNOON INTO TONIGHT. HIGH RESOLUTION MODELS...ARW/NMM/NAM
NEST...SHOW SETTLE DIFFERENCES ON PLACEMENT OF SURFACE FRONT OVER
SOUTHERN IOWA. WITH THE 24.00Z GFS/NAM FARTHER NORTH SOLUTION...CONVECTION
DEVELOPS OVER THE SOUTHERN HALF OF THE FORECAST AREA. WITH THE
FARTHER SOLUTION PLACEMENT OF THE FRONT...THE 24.00Z ECMWF AND
HIGH RESOLUTION MODELS FOCUS CONVECTION OVER THE FAR SOUTHERN
FORECAST AREA OR JUST TO THE SOUTH OF THE FORECAST AREA THIS
AFTERNOON INTO TONIGHT. WITH THIS...CONFIDENCE TODAY INTO TONIGHT
REMAINS ON THE LOW SIDE. GIVEN THE HIGH RESOLUTION MODELS ARE
SOMEWHAT IN AGREEMENT WITH THE 24.00Z ECMWF...WILL CONTINUE TO
FOCUS HIGHER PRECIPITATION CHANCES OVER THE SOUTHERN PART OF THE
FORECAST AREA TODAY INTO TONIGHT.
MODELS CONTINUE TO SHOW DECENT SHEAR OF 30 TO 40 KNOTS OF 0-3KM
SHEAR/AROUND 50 KNOTS OF 0-6KM SHEAR ACROSS MUCH OF THE FORECAST
AREA...AND 0-6KM MOST UNSTABLE CAPE OF 1000-2000 J/KG ACROSS THE
EXTREME SOUTHERN PORTION OF THE FORECAST AREA. CANNOT RULE THE
POSSIBILITY OF AN ISOLATED LARGE HAIL OR DAMAGING WIND WITH ANY
THUNDERSTORMS CONFINED TO THE FAR SOUTHERN PART OF THE FORECAST
AREA. THE BIGGEST CONCERN IS THE POSSIBILITY OF ENTRAINMENT OF
CONVECTION ACROSS THE FAR SOUTHERN PART OF THE FORECAST AREA LATE
THIS EVENING INTO TONIGHT...WHICH WOULD POSE A FLASH FLOODING
THREAT. THE MAJORITY OF THE HIGH RESOLUTION MODELS SUGGEST
ENTRAINMENT OF THE CONVECTION TO BE JUST SOUTH OF THE FORECAST
AREA. IF CONVECTION DEVELOPS FARTHER NORTH...THEN THE FAR SOUTHERN
FORECAST AREA...COULD SEE THE POTENTIAL FOR LOCALLY HEAVY
RAINFALL.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 346 AM CDT WED JUN 24 2015
MAIN SHORTWAVE TROUGH PUSHES EAST OF THE FORECAST AREA AND WEAK
SUBSIDENCE BEHIND SHORTWAVE TROUGH WILL ALLOW FOR PRECIPITATION TO
MOVE EAST OF THE FORECAST AREA THURSDAY INTO THURSDAY NIGHT. THE
24.00Z GFS/NAM/ECMWF ARE IN AGREEMENT IN DIGGING UPPER LEVEL
TROUGH INTO THE OHIO RIVER VALLEY FRIDAY. WITH DEEPER
MOISTURE/CONVERGENCE WEST/SOUTH OF THE FORECAST AREA...AND A DRY
EASTERLY FLOW ALOFT OVER FORECAST AREA. HAVE REDUCED PRECIPITATION
CHANCES OVER THE EASTERN FORECAST AREA AND KEPT PRECIPITATION
CHANCES CONFINED OVER THE WESTERN FORECAST AREA.
THE LATEST 24.00Z GFS/ECMWF/GEM CONTINUE TO DIG UPPER LEVEL TROUGH
OVER THE OHIO RIVER VALLEY SATURDAY INTO EARLY NEXT WEEK. TIMING
DIFFERENCES ON EACH INDIVIDUAL IMPULSE EMBEDDED IN THE NORTHWEST
FLOW ALOFT ARE INDICATED BETWEEN THE MODELS THROUGH THIS PERIOD.
WILL CONTINUE WITH TREND OF PERIODIC SMALL CHANCES OF PRECIPITATION
SATURDAY THROUGH TUESDAY. TEMPERATURES THROUGH THE PERIOD ARE
EXPECTED TO BE SLIGHTLY BELOW NORMAL OR NEAR NORMAL...AS NORTHERLY
FLOW ALOFT ADVECTS COOLER AIRMASS INTO THE FORECAST AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1141 PM CDT TUE JUN 23 2015
THE FRONT REMAINS OVER CENTRAL KANSAS INTO CENTRAL MISSOURI LATE
THIS EVENING. CONVECTION HAS FORMED NEAR AN AREA OF LOW PRESSURE
OVER EASTERN COLORADO AND WAS MOVING EAST ALONG AND NORTH OF THE
FRONT. NO MODEL IS PICKING UP ON THIS CONVECTION WITH THE 24.00Z
NAM AND 24.03Z HRRR COMPLETELY WHIFFING ON THIS. THE 24.00Z SPC
WRF AT LEAST SHOWED THIS BUT THEN DIES IT OUT IN FAVOR OF
DEVELOPING CONVECTION OVER EASTERN NEBRASKA AND SOUTHERN
IOWA...WHICH IS WHERE THE NAM AND HRRR ALSO TRY TO INITIATE
OVERNIGHT. WITH BOTH SCENARIOS...THE CONVECTION WILL STAY TO THE
SOUTH TONIGHT BUT IT WILL IMPACT HOW FAR NORTH THE FRONT CAN
PROGRESS WEDNESDAY. THE NAM WITH THE 00Z RUN IS EVEN FARTHER NORTH
WITH DEVELOPMENT LATE WEDNESDAY AFTERNOON AND EVENING THAN WHAT
THE 18Z RUN WAS. THE SPC WRF SUGGESTS THE FRONT STAYS WELL TO THE
SOUTH WITH DEVELOPMENT OCCURRING ACROSS SOUTHERN NEBRASKA AND IOWA
INTO NORTHERN MISSOURI. THE 24.00Z GFS LOOKS TO BE IN BETWEEN
THESE OTHER TWO SOLUTIONS WITH MOST OF THE ACTIVITY OVER THE
NORTHERN HALF OF IOWA. WITH TWO OUT THREE OF THE NEW MODEL RUNS
KEEPING THE CONVECTION SOUTH OF THE AREA WEDNESDAY...PLAN TO TO DO
THE SAME WITH THE UPCOMING TAFS.
&&
.HYDROLOGY...
ISSUED AT 346 AM CDT WED JUN 24 2015
THE RECENT RAINFALL THAT OCCURRED MONDAY MORNING NEAR THE
MINNESOTA/IOWA BORDER HAS CAUSED HIGH RIVER LEVELS ON AREA RIVERS
AND STREAMS. MANY OF THE RIVERS HAVE BEGUN TO RECEDE...HOWEVER SOME
FLOODING REMAINS ALONG THE CEDAR RIVER. REFER TO THE LATEST FLOOD
STATEMENTS FOR THE LATEST STAGES AND FORECAST.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DTJ
LONG TERM...DTJ
AVIATION...04
HYDROLOGY...DTJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1141 PM CDT TUE JUN 23 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 341 PM CDT TUE JUN 23 2015
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED SUBTROPICAL RIDGING ENCOMPASSING THE SOUTHERN U.S.. WHILE A
WEST-NORTHWEST FLOW RUNS FROM THE PACIFIC NORTHWEST INTO THE MID-
ATLANTIC. THE TWO MAIN SHORTWAVES OF NOTE WERE OVER THE SIOUX FALLS
AREA AND SOUTHERN BRITISH COLUMBIA. THE ONE IN SIOUX FALLS ALONG
WITH A WIDE AREA OF LOW TO MID LEVEL FRONTOGENESIS WAS HELPING TO
PRODUCE PLENTY OF ALTOSTRATUS FROM SOUTH DAKOTA/NEBRASKA EAST INTO
THE SOUTHERN PORTION OF THE FORECAST AREA. AIRMASS HAS BEEN TOO DRY
TO SUPPORT ANY PRECIPITATION DESPITE SEEING ECHOES ON RADAR...AS
REFLECTED BY THE 12Z MPX SOUNDING WITH A 700MB DEWPOINT DEPRESSION
OF 40C. ONLY A VERY FEW SITES HAVE REPORTED SPRINKLES. MAIN SURFACE
FRONTAL BOUNDARY ASSOCIATED WITH THE FRONTOGENESIS WAS WELL TO THE
SOUTH...SITUATED JUST SOUTH OF I-70 AND WAS VERY SLOWLY LIFTING
NORTH TODAY. THAT NORTHWARD PROGRESS HAS BEEN HELD BACK BY A
PERSISTENT COMPLEX OF CONVECTION FROM SOUTHEAST NEBRASKA INTO THE
KANSAS CITY AREA. SUNSHINE TODAY COMBINED WITH 850MB TEMPS AROUND
10C HAS RESULTED IN HIGHS MOSTLY IN THE 70S. MUCH LOWER DEWPOINTS
TODAY THAN YESTERDAY WITH MIXING AND DRY AIR RESULTING IN READINGS
OF 45 TO 55F.
LOOK FOR A CONTINUATION OF QUIET CONDITIONS TONIGHT ACROSS THE
FORECAST AREA AS THE AREA OF HIGH PRESSURE HELPING TO PROVIDE THE
DRY CONDITIONS ONLY DRIFTS OFF TO THE SOUTHEAST. WE WILL HAVE TO
DEAL WITH THE SOME HIGHER BASED FRONTOGENESIS...YIELDING SOME
ALTOSTRATUS AS WE ARE SEEING TODAY. THESE CLOUDS SHOULD HELP TO
PRECLUDE FOG FORMATION...AND ALSO KEEP TEMPERATURES FROM FALLING
BELOW THE MID 50S.
THE MORE INTERESTING PART OF THE SHORT TERM IS FOR WEDNESDAY. MODELS
CONTINUE TO ADVERTISE THAT THE FRONTAL BOUNDARY IN KANSAS WILL LIFT
NORTHWARD OVER THE NEXT 24 HOURS...IN RESPONSE TO A MONSOONAL
SHORTWAVE COMING OUT OF COLORADO AND ROTATING AROUND THE SOUTHERN
U.S. SUBTROPICAL RIDGE. AS THIS OCCURS WITH THE NOCTURNAL LOW LEVEL
JET...MODELS ARE ADVERTISING AT LEAST CONVECTION IF NOT AN MCS TO
DEVELOP OVER EASTERN NEBRASKA AND WESTERN IOWA LATE TONIGHT. CORFIDI
VECTORS WOULD TAKE THIS MCS INTO NORTHERN MO WEDNESDAY MORNING...
HOLDING THE FRONT BACK. HOWEVER...SOME GUIDANCE LIKE THE 23.12Z
GFS/NAM WANT TO KEEP MOVING THE FRONT NORTH INTO THE AFTERNOON...
SPREADING EITHER PREVIOUS OR NEW CONVECTION INTO NORTHEAST IA AND
SOUTHWEST WI. BELIEVE THIS IS GOING TO BE TOUGH AS CLOUD DEBRIS
LIMITS DAYTIME MIXING...AND CONVECTIVE OUTFLOW HOLDS THE BOUNDARY
BACK. MORE LIKELY...WHEN NEW CONVECTION FIRES IT WILL BE FARTHER
SOUTH CLOSER TO THE FRONT...WHICH SHOULD BE HUNG UP NEAR THE MO/IA
BORDER BY 00Z THU. THE 23.12Z ECMWF REMAINS THE FARTHEST SOUTH MODEL
WITH THE FRONT AND CONVECTION...AND SEEMS MOST REASONABLE GIVEN
EXPECTED CONVECTION TRACKS. THEREFORE...PRECIPITATION CHANCES ARE
HIGHEST IN NORTHEAST IA BUT STILL ONLY AS MUCH AS 50 PERCENT BY LATE
IN THE DAY GIVEN ANTICIPATION FOR MOST CONVECTION TO STAY SOUTH.
GIVEN THE MAJORITY OF CAPE TO STAY WELL SOUTH OF THE AREA...THE
SLIGHT RISK ON SPCS DAY 2 OUTLOOK WAS SHIFTED MOSTLY OUT OF THE
FORECAST AREA. ITS WORTH NOTING THAT MODELS...OUTSIDE THE 23.12Z
ECMWF...HAVE REALLY STRUGGLED WITH THE ONGOING CONVECTION NORTH OF
THE FRONT IN THE KANSAS CITY AREA.
THERE IS ALSO SOME CONCERN FOR SHOWERS AND STORMS TO FIRE NORTH OF
HIGHWAY 29 WEDNESDAY AFTERNOON...RELATED TO THE SHORTWAVE IN BRITISH
COLUMBIA HEADING INTO NORTHERN PORTIONS OF MN OR WI. THE ECMWF IS
SLOWEST WITH THE SHORTWAVE AND THEREFORE IS DRY...WHEREAS THE GFS
AND NAM ARE FASTER AND HAVE PRECIP. THE GFS/NAM ALSO HAVE HIGHER
SURFACE DEWPOINTS WHICH SEEM TOO HIGH. THEREFORE...HAVE ONLY KEPT A
20 PERCENT CHANCE IN TAYLOR COUNTY LATE IN THE DAY.
WITH 850MB TEMPS IN THE 12-14C RANGE AND SOME SUN LIKELY FOR AT
LEAST THE MORNING HOURS...HIGHS SHOULD PUSH INTO THE MID 70S TO LOW
80S...WARMEST TO THE NORTH WHERE LONGER PERIOD OF SUN IS EXPECTED.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 341 PM CDT TUE JUN 23 2015
23.12Z ECMWF/GFS/CANADIAN MAINTAIN THE SAME LONG WAVE PATTERN THEY
HAVE BEEN SHOWING THE PAST SEVERAL DAYS...WITH STRONG SUBTROPICAL
RIDGING SHIFTING AND BUILDING OVER THE WESTERN U.S. ON
THURSDAY...CAUSING FAIRLY DEEP TROUGHING FOR THIS TIME OF YEAR OVER
THE EASTERN U.S.. THIS SHIFT IS IN RESPONSE TO THE MADDEN JULIAN
OSCILLATION GOING INTO AN ANOMALOUSLY STRONG PHASE 6. WHAT THIS
MEANS FOR THE FORECAST AREA IS TEMPERATURES TO HOLD AT OR NEAR
SEASONABLE NORMALS...WITH PERHAPS A SLOW WARMUP LATE IN THE WEEKEND
INTO EARLY NEXT WEEK. ANY GULF OF MEXICO RETURN OF MOISTURE SHOULD
GET SHUTOFF WITH MOISTURE SOURCES MOSTLY TURNING TO
EVAPOTRANSPIRATION AND WHAT SYSTEMS CAN BRING OFF THE PACIFIC DOWN
THE RIDGE.
THE MAIN FOCUS FOR PRECIPITATION REMAINS WEDNESDAY NIGHT.
HOWEVER...SIMILAR TO WEDNESDAY...HOW FAR NORTH THE WARM FRONT NEAR
THE IA/MO BORDER AT 00Z THU REALLY DETERMINES THE CONVECTION
CHANCES. CURRENT THINKING LIES ALONG THE MORE PREFERRED ECMWF VERSUS
THE BIASED NORTH GFS/NAM/SREF/CANADIAN...WHICH SUGGESTS ANOTHER MCS
FORMING OVER CENTRAL IOWA WEDNESDAY EVENING...MARCHING LIKELY
SOUTHEASTWARD FOLLOWING CORFIDI VECTORS. THIS IS IN LINE WITH THE
HIGHEST SPC DAY 2 OUTLOOK PROBABILITIES. THE NORTHERN PART OF THIS
MCS COULD CLIP OUR FAR SOUTH...THUS HAVE THE HIGHEST 50-60 PERCENT
CHANCES THERE FOR THE EVENING. TRIMMED CHANCES BACK FARTHER NORTH
AND AREAS NORTH OF U.S. HIGHWAY 18 MAY END UP DRY. THE LONE
EXCEPTION WOULD BE NORTH OF HIGHWAY 29...CLOSER TO THAT SHORTWAVE
TROUGH MARCHING ACROSS MN AND NORTHERN WI. PRECIPITATION SHOULD
DIMINISH WEST TO EAST DURING THE OVERNIGHT HOURS AS THE MCS AND
SHORTWAVE TROUGHS MOVE FURTHER AWAY FROM THE AREA.
FOR THURSDAY AND FRIDAY...THE 23.12Z GFS AND TO A LESSER EXTENT THE
NAM WANT TO FIRE UP SOME DIURNAL SHOWERS AND STORMS...ASSOCIATED
WITH WEAK SHORTWAVES DROPPING THROUGH THE NORTHWEST FLOW. THE 23.12Z
ECMWF SHOWS THESE SAME SHORTWAVES BUT IS DRY. MUCH OF THE DIFFERENCE
RELATES TO BOUNDARY LAYER MOISTURE AND ITS IMPACT TO CAPE. AT BOTH
00Z FRI AND 00Z SAT...THE GFS IS NEARLY 10F HIGHER ON SURFACE
DEWPOINTS TO THE ECMWF. THINKING THE ECMWF IS MORE CORRECT AND THUS
HAVE ONLY 20-30 PERCENT CHANCES AT MOST...HIGHEST IN WESTERN AREAS.
SATURDAY LOOKS DRY WITH HIGH PRESSURE IN PLACE...BUT THEN THERE IS
AN ISSUE WITH SUNDAY INTO MONDAY WITH MODELS TIMING A STRONGER
SHORTWAVE TROUGH DROPPING THROUGH THE NORTHWEST FLOW. THE 23.12Z
ECMWF IS FASTEST AND SPREADS SOME CONVECTION ACROSS THE AREA ON
SUNDAY...WHEREAS THE 23.12Z CANADIAN/GFS WAIT UNTIL EITHER LATER
SUNDAY NIGHT OR MONDAY. GIVEN THE SPREAD...HAVE KEPT A 20-40 PERCENT
CHANCE FOR ALL 3 12 HOUR TIME PERIOD. NEEDLESS TO SAY A GOOD PORTION
CAN PROBABLY BE DRIED OUT IN LATER FORECASTS ONCE THE TIMING GETS
RESOLVED. ANOTHER NORTHWEST FLOW WAVE IS PROGGED FOR TUESDAY...
RESULTING IN MORE CHANCES OF PRECIPITATION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1141 PM CDT TUE JUN 23 2015
THE FRONT REMAINS OVER CENTRAL KANSAS INTO CENTRAL MISSOURI LATE
THIS EVENING. CONVECTION HAS FORMED NEAR AN AREA OF LOW PRESSURE
OVER EASTERN COLORADO AND WAS MOVING EAST ALONG AND NORTH OF THE
FRONT. NO MODEL IS PICKING UP ON THIS CONVECTION WITH THE 24.00Z
NAM AND 24.03Z HRRR COMPLETELY WHIFFING ON THIS. THE 24.00Z SPC
WRF AT LEAST SHOWED THIS BUT THEN DIES IT OUT IN FAVOR OF
DEVELOPING CONVECTION OVER EASTERN NEBRASKA AND SOUTHERN
IOWA...WHICH IS WHERE THE NAM AND HRRR ALSO TRY TO INITIATE
OVERNIGHT. WITH BOTH SCENARIOS...THE CONVECTION WILL STAY TO THE
SOUTH TONIGHT BUT IT WILL IMPACT HOW FAR NORTH THE FRONT CAN
PROGRESS WEDNESDAY. THE NAM WITH THE 00Z RUN IS EVEN FARTHER NORTH
WITH DEVELOPMENT LATE WEDNESDAY AFTERNOON AND EVENING THAN WHAT
THE 18Z RUN WAS. THE SPC WRF SUGGESTS THE FRONT STAYS WELL TO THE
SOUTH WITH DEVELOPMENT OCCURRING ACROSS SOUTHERN NEBRASKA AND IOWA
INTO NORTHERN MISSOURI. THE 24.00Z GFS LOOKS TO BE IN BETWEEN
THESE OTHER TWO SOLUTIONS WITH MOST OF THE ACTIVITY OVER THE
NORTHERN HALF OF IOWA. WITH TWO OUT THREE OF THE NEW MODEL RUNS
KEEPING THE CONVECTION SOUTH OF THE AREA WEDNESDAY...PLAN TO TO DO
THE SAME WITH THE UPCOMING TAFS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
730 PM MDT THU JUN 25 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 330 PM MDT THU JUN 25 2015
ANTICIPATED SEVERE WEATHER EVENT ONGOING THIS AFTERNOON. AFTER
MORNING SEVERE THUNDERSTORMS WE ARE IN A LULL RIGHT NOW AND
GETTING READY FOR ROUND TWO.
CURRENTLY...MCS COMPLEX HAS CLEARED THE NEBRASKA PANHANDLE THIS
AFTERNOON AND IS PUSHING OFF INTO CENTRAL NEBRASKA. LATEST RADAR
MOSAIC SHOWING ISOLATED TO SCATTERED THUNDERSTORMS BEGINNING TO
DEVELOP OVER NORTH CENTRAL AND NORTHEASTERN WYOMING...MOVING
SOUTHEAST. LATEST MESOANALYSIS PAGE SHOWING SOUTHEAST WYOMING IN
AN AREA OF UNCAPPED ENVIRONMENT...WITH SURFACE BASED CAPES BETWEEN
2500 AND 3500 J/KG. AREAS THAT SAW CONVECTION THIS MORNING ARE
SEEING SOME CONVECTIVE INHIBITION RANGING FROM -50 TO -75 J/KG
OVER THE NORTHERN PANHANDLE. WATER VAPOR IMAGERY SHOWING A WEAK
SHORTWAVE MOVING INTO NORTH CENTRAL WYOMING THIS AFTERNOON AND
THIS SHOULD BE THE CATALYST FOR MORE WIDESPREAD CONVECTION THIS
AFTERNOON.
FOR THE REMAINDER OF THIS AFTERNOON AND EVENING...A SCATTERED
COVERAGE OF STORMS BEING FORECAST FOR AREAS EAST OF THE LARAMIE
RANGE. WITH AFTERNOON HEATING...CAPE SHOULD REMAIN HIGH...IN THE
2500-3000 J/KG RANGE. LATEST HRRR SIMULATED RADAR IMAGERY SHOWING
THE MAJORITY OF CONVECTION OVER THE SOUTHERN PANHANDLE THROUGH MID
EVENING.
ONE AREA OF CONCERN HYDRO WISE. MORNING CONVECTION OVER DAWES AND
NORTHERN SIOUX COUNTIES HAVE PRIMED THIS AREA FOR POTENTIAL FLASH
FLOODING. WE RECEIVED REPORTS OF UP TO AS MUCH AS 2.5 INCHES OF
RAIN HAS THAT HAS ALREADY FALLEN IN DAWES COUNTY JUST SOUTH OF
CHADRON. REPORTS OVER NORTHERN SIOUX AROUND AN INCH AND FURTHER
WEST IN CONVERSE COUNTY...WE RECEIVED REPORTS CLOSE TO AN INCH
FROM MORNING CONVECTION. WILL KEEP THE FLASH FLOOD WATCH GOING AS
ANY MORE STORMS UP THERE COULD PRODUCE FLOODING CONDITIONS
QUICKLY.
SHORTWAVE PASSES TO THE EAST INTO WESTERN NEBRASKA AFTER 06Z THIS
EVENING AND CONVECTION SHOULD COME TO AN END FROM WEST TO EAST AS
THIS OCCURS THROUGH THE EVENING HOURS. CONTINUED THE POTENTIAL FOR
AM FOG ESPECIALLY ACROSS THE PANHANDLE WHERE NORTHEAST WINDS WILL
LINGER.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 330 PM MDT THU JUN 25 2015
RELATIVELY QUIET WEATHER THIS WEEKEND AS A STRONG UPPER LEVEL
HIGH DEVELOPS NEAR THE FOUR CORNERS REGION AND GRADUALLY DRIFTS
NORTHWARD OVER THE NORTHERN GREAT BASIN. MODEL SOUNDINGS CONTINUE
TO INDICATE STRONG MIDLEVEL SUBSIDENCE OVER THE FORECAST AREA
WHICH WILL GREATLY INHIBIT CONVECTION SATURDAY AND SUNDAY
AFTERNOON. CAN NOT RULE OUT A FEW THUNDER SHOWERS OVER THE
MOUNTAINS THIS WEEKEND...OTHERWISE KEPT POP BELOW 10 PERCENT OVER
THE HIGH PLAINS. ALTHOUGH PRECIPITATION CHANCES WILL BE
LOW...DEWPOINTS WILL BE HIGH EAST OF THE LARAMIE RANGE WITH PRETTY
HIGH RELATIVE HUMIDITIES. HOWEVER...SUBSIDENCE ALOFT WILL BE TOO
GREAT TO OVERCOME FOR DEEP CONVECTION. THIS MAY CHANGE BY EARLY
NEXT WEEK AS THE UPPER LEVEL HIGH DRIFTS TO THE
WEST AND WEAKENS...ALLOWING SHORTWAVE ACTIVITY AND A MORE
FAVORABLE SHEAR PROFILE TO ENTER THE FORECAST AREA. INCREASED POP
TUESDAY THROUGH THURSDAY...WITH THE HIGHEST POTENTIAL FOR TSTORMS
OVER SOUTHEAST WYOMING. HIGH TEMPERATURES WILL BE NEAR OR
SLIGHTLY ABOVE NORMAL FOR THIS TIME OF THE YEAR WITH HIGHS IN THE
80S TO NEAR 90. MODELS THEN INDICATE A COOL FRONT QUICKLY MOVING
SOUTHWARD ACROSS THE AREA BY WEDNESDAY EVENING...WHICH MAY RESULT
IN TEMPERATURES SLIGHTLY BELOW NORMAL BY THE END OF NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH FRIDAY AFTERNOON)
THE STRONGEST THUNDERSTORMS HAVE PUSHED EAST OF KSNY AND KBFF THIS
EVENING. IFR CONDITIONS AND HEAVY RAIN WILL BE POSSIBLE OVER THE
NEXT FEW HOURS UNTIL THUNDERSTORMS DISSIPATE AFTER 03Z. AFTER A
BRIEF BREAK...IFR CONDITIONS MAY RETURN TO LOCATIONS EAST OF THE
LARAMIE RANGE DUE TO LOW CLOUDS AND FOG. PATCHY FOG AND LOW CIGS
WILL CONTINUE INTO EARLY FRIDAY MORNING.
&&
.FIRE WEATHER...
ISSUED AT 330 PM MDT THU JUN 25 2015
ACTIVE WEATHER TODAY AS SCATTERED SHOWERS AND THUNDERSTORMS WILL
IMPACT MUCH OF SOUTHEAST WYOMING AND NEBRASKA PANHANDLE. THESE
STORMS LOOK TO GRADUALLY DECREASE AS THE EVENING PROGRESSES.
A DRIER DAY ON TAP FOR FRIDAY AS THE FRONT THATS CURRENTLY OVER THE
AREA MOVES EAST. NICE AND DRY WEATHER FOR THE WEEKEND WITH AFTERNOON
HUMIDITIES IN THE UPPER TEENS WEST OF THE LARAMIE RANGE AND LOWER
30S EAST. NO FIRE WEATHER CONCERNS AS AREA FUELS ARE RATED
NONRECEPTIVE TO LARGE FIRE GROWTH.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...FLASH FLOOD WATCH UNTIL MIDNIGHT MDT TONIGHT FOR WYZ102.
NE...FLASH FLOOD WATCH UNTIL MIDNIGHT MDT TONIGHT FOR NEZ002-095.
&&
$$
SHORT TERM...GCC
LONG TERM...TJT
AVIATION...TJT
FIRE WEATHER...GCC
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
1247 AM CDT FRI JUN 26 2015
.AVIATION...26/06Z TAF CYCLE
VFR CONDS WL PREVAIL THRU THE MRNG HRS ACRS THE FA. A CDFNT IS
FCST TO MOVE INTO NRN AR FRI AFTN. SCTD SHRA/TSRA WL DVLP ALONG
THE FNT...PRODUCING MAINLY MVFR CONDS. CONVECTION WL BCM MORE
ORGANIZED AS IT SHIFTS SWD INTO CNTRL AR BY EARLY FRI EVENING...
AND EVENTUALLY AFFECTING SRN AR LATE IN THE FCST PD. /44/
&&
.PREV DISCUSSION... /ISSUED 220 PM CDT THU JUN 25 2015/
SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT
TODAY...HAVE CONTINUED TO SEE A FEW CLOUDS BEGIN TO POP IN THE HEAT
OF THE DAY...GENERALLY ACROSS SOUTHERN ARKANSAS. WITHIN THE PAST
HOUR OR TWO... HAVE BEGUN TO SEE A FEW SHOWERS AND THUNDERSTORMS
FIRE IN NORTHERN LOUISIANA. AT THIS TIME...DO HAVE POPS ACROSS
SOUTHERN ARKANSAS. HRRR SUGGESTS STORMS COULD FIRE AS FAR NORTH AS
LITTLE ROCK...BUT DO HAVE SOME DOUBTS THAT CENTRAL ARKANSAS WILL SEE
RAIN. AS A RESULT...KEPT SLIGHT CHANCE POPS LIMITED TO SOUTHERN
ARKANSAS.
UPPER LEVEL RIDGE HAS BEGUN TO RETROGRADE TO THE WEST WITH WESTERLY
FLOW SETTING UP ALOFT. NORTHWESTERLY FLOW WILL BE MOVING INTO THE
REGION AND HELP TO DRIVE A FRONT INTO THE STATE ON FRIDAY. 12Z WRF
SUGGESTS PRECIP WILL BE IN PLACE ACROSS NORTHERN ARKANSAS BEFORE 12Z
ON FRIDAY. DO THINK THE FRONT WILL BE A BIT QUICKER THAN THE MODELS
SUGGEST...BUT BELIEVE THE WRF IS MUCH TOO QUICK. THEREFORE JUST KEPT
CHANCE POPS MENTIONED ACROSS NORTHERN ARKANSAS DURING THE MORNING
HOURS.
AMPLE CAPE WILL BE AVAILABLE AHEAD OF THE FRONT ON FRIDAY WITH DEEP
LAYER SHEAR AROUND 30 KNOTS. MID LEVEL LAPSE RATES...WILL NOT BE
OUTRAGEOUS...BUT DO EXPECT DAMAGING WIND GUSTS TO BE THE PRIMARY
THREAT.
IT DOES APPEAR THE COLD FRONT WILL CLEAR THE STATE BY MID MORNING ON
FRIDAY WITH DRY AND NOTICEABLY COOLER AND DRIER AIR FILTERING INTO
THE STATE. DRY WEATHER WILL BE SHORT LIVED AS THE NEXT CHANCE FOR
PRECIPITATION MOVES INTO NORTHERN ARKANSAS AS THE SHORT TERM ENDS.
LONG TERM...MONDAY THROUGH THURSDAY
FLOW ALOFT WILL BE FROM THE NW OVER THE REGION AT THE START OF THE
LONG TERM PERIOD AS AN ELONGATED UPPER RIDGE WILL BE OVER THE
ROCKIES...WITH A TROUGH OVER THE GREAT LAKES REGION. A NEW COLD
FRONT WILL SLOW OVER PORTIONS OF THE STATE...WITH CHANCES FOR
SHOWERS AND THUNDERSTORMS RETURNING. INITIALLY...BEST POPS WILL BE
ACROSS THE NRN COUNTIES...BUT DO THINK SOME CHANCES FOR PRECIP WILL
EXIST FURTHER SOUTH BY LATE MON INTO TUE WITH THE FRONT WASHING OUT.
SRLY FLOW WILL RETURN FOR TUE AND THROUGH MUCH OF THE REST OF THE
FORECAST...WHICH WILL ALLOW FOR TEMPS TO INCREASE FROM JUST BELOW
NORMAL...TO AROUND NORMAL FOR MUCH OF NEXT WEEK. CHANCES FOR
DIURNALLY DRIVEN CONVECTION WILL BE SEEN...ESPECIALLY WITH THE UPPER
RIDGE REMAINING WEST OF THE STATE...AND AR IN GENERAL NW FLOW ALOFT.
BY THE END OF NEXT WEEK...ANOTHER COLD FRONT WILL ATTEMPT TO MOVE
INTO THE STATE...WITH ANOTHER SHOT OF COOLER AIR AND MORE CHANCES
FOR PRECIP.
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
1035 PM MST THU JUN 25 2015
.UPDATE...UPDATED AVIATION DISCUSSION...
.SYNOPSIS...
ABOVE NORMAL TEMPERATURES WILL PERSIST ACROSS THE REGION THROUGH THE
WEEKEND. THUNDERSTORMS ARE EXPECTED TO BE LARGELY CONFINED TO THE
WHITE MOUNTAINS AND SOUTHEAST ARIZONA THROUGH SATURDAY...BUT WITH
STRONG WINDS AND AREAS OF BLOWING DUST POSSIBLE ON THE LOWER DESERTS
DUE TO DISTANT STORMS. MORE HUMID AIR IS ANTICIPATED TO OVERSPREAD
THE REGION BEGINNING LATER IN THE WEEKEND WITH STORM CHANCES
EXPANDING TO MANY LOWER DESERT LOCATIONS BY EARLY NEXT WEEK. THE
INCREASE IN MONSOON STORM ACTIVITY COULD LEAD TO SLIGHTLY COOLER
DAYTIMES BUT WARMER OVERNIGHTS.
&&
.DISCUSSION... AS EXPECTED...TODAY WAS NOT QUITE AS ACTIVE ACROSS
OUR CWA THEN WHAT WE SAW YESTERDAY...WHEN A WEAK INVERTED TROF
HELPED TO TRIGGER THUNDERSTORM ACTIVITY ACROSS THE HIGHER TERRAIN OF
SOUTH-CENTRAL ARIZONA...WHICH GENERATED AN OUTFLOW BOUNDARY THAT
MOVED WESTWARD INTO THE GREATER PHOENIX AREA. ALTHOUGH A FEW STORMS
DID AGAIN DEVELOP OVER GILA COUNTY...TODAY/S ACTIVITY WAS MORE
FOCUSED OVER SE AZ...WITH TUCSON INTERNATIONAL AIRPORT SEEING WIND
GUSTS UP TO 60 MPH FROM NEARBY THUNDERSTORMS. ALTHOUGH OUTFLOWS FROM
THE STORMS OVER THE TUCSON AREA DID ATTEMPT TO MOVE NORTHWARD...THEY
PRETTY MUCH DISSIPATED WELL TO THE SOUTH OF OUR CWA. ANOTHER AREA
THAT ACTUALLY SAW A FEW SPRINKLES TODAY...WITH CONSIDERABLE
CLOUDINESS THAT KEPT HIGHS DOWN AT/BELOW 100 WAS THE YUMA AREA. THE
CLOUDINESS OVER THAT AREA IS NOW BEGINNING TO THIN/CLEAR AS THE
MOISTURE PLUME IS PUSHED OFF TO THE WEST. AS FAR AS THE FORECAST FOR
THE REST OF THE NIGHT AND EARLY FRIDAY IS CONCERNED...IT SHOULD BE
PRETTY QUIET...WITH THE LATEST HRRR KEEPING CONVECTIVE ACTIVITY
PRETTY MUCH OVER THE TUCSON CWA. OTHER THAN SOME MINOR ADJUSTMENTS
TO HOURLY TRENDS...INHERITED FORECASTS ARE LOOKING GOOD.
&&
.PREVIOUS DISCUSSION... STRONG HIGH PRESSURE ALOFT WAS SITUATED OVER
THE DESERT SOUTHWEST EARLY THIS AFTERNOON WITH THE UPPER HIGH CENTER
LOCATED OVER FAR NCENTRAL ARIZONA NEAR THE UTAH BORDER. H5 HEIGHTS
REMAINED HIGH ACROSS SRN AZ...NEAR 592DM AND UNDER MOSTLY SUNNY
SKIES THE CENTRAL DESERTS WERE RAPIDLY CLIMBING TOWARDS 110 DEGREES
AS OF 1 PM. SURFACE DEWPOINTS OVER THE CENTRAL DESERTS WERE ELEVATED
EARLY THIS AFTERNOON COMPARED TO 24 HOURS AGO...RANGING FROM UPPER
40S TO MID 50S...BUT THEY WILL LIKELY DROP ANOTHER FEW DEGREES BY
LATE AFTERNOON AND WILL BE TOO LOW TO SUPPORT DESERT CONVECTION.
RADAR AS WELL AS IR/LIGHTNING IMAGERY SHOWED A FEW STORMS DEVELOPING
OVER FAR SERN AZ AND THE WHITE MOUNTAINS BUT LITTLE WAS HAPPENING
CONVECTIVELY OVER SRN GILA COUNTY. PART OF THE REDUCTION IN
CONVECTION IS DUE TO THE COOLER TEMPS TODAY COMPARED TO YESTERDAY.
FOR TONIGHT THROUGH FRIDAY NIGHT...THE STRONG UPPER HIGH WILL REMAIN
CENTERED TO OUR NORTH...GIVING THE SRN DESERTS A WEAK ELY STEERING
FLOW MOSTLY AOB 15KT. MODEL GUIDANCE IS CONSISTENT IN CALLING FOR
LIMITED MOISTURE AND INSTABILITY OVER THE LOWER DESERTS...WITH CAPE
VALUES MOSTLY BELOW 200J/KG. THE STRENGTH OF THE UPPER HIGH WILL ACT
TO CAP CONVECTION SOMEWHAT OVER OUR AREA WITH THE ONLY REAL THREAT
FOR STORMS TO FOCUS OVER THE HIGHER TERRAIN OF SOUTHERN GILA COUNTY.
ESSENTIALLY WE ARE LOOKING AT LOW GRADE MONSOON CONDITIONS TONIGHT
THROUGH FRIDAY NIGHT WITH SLIGHT CHANCES ACROSS ZONE 24 AND SINGLE
DIGIT POPS ELSEWHERE. GIVEN THE RATHER LOW GRADE CONDITIONS...THE
THREAT OF BLOWING DUST INTO NRN PINAL COUNTY OR THE EAST VALLEY WILL
BE MINIMAL AS WELL. LOW GRADE MONSOON CONDITIONS WILL ALSO CONTINUE
DURING THE DAY ON SATURDAY.
UNDER PARTLY TO MOSTLY SUNNY SKIES FRIDAY INTO SATURDAY...HIGH TEMPS
WILL STAY WELL ABOVE SEASONAL NORMALS WITH MOST OF THE HOTTER
DESERTS REACHING OR EXCEEDING 110 DEGREES. WE EXPECT HIGHS TO STAY
SLIGHTLY BELOW EXCESSIVE HEAT WARNING CRITERIA HOWEVER.
OVERNIGHT SATURDAY INTO SUNDAY A DEEPER MOISTURE FROM
THE EAST WILL OVERSPREAD THE AREA...INCREASING CHANCES FOR SHOWER
AND THUNDERSTORM ACTIVITY FOR THE LATE WEEKEND AND EARLY NEXT WEEK.
FLOW THROUGH THE 700-500MB LAYER BECOMES A BIT MORE UNIDIRECTIONAL
FROM THE SOUTHEAST AND ELEVATED IN VELOCITY ACROSS SOUTHEAST AZ
FIRST ON SUNDAY BUT THEN EXPANDS INTO SOUTH-CENTRAL AND SOUTHWEST AZ
LATER INTO THE DAY ON MONDAY. PWATS NEAR THE 1.25 INCH MARK AND
850MB DEWPOINTS ARE PROGGED INTO THE 8-10C RANGE ACROSS THE NORTHERN
CWA TIER AND 10C+ ACROSS SW AZ AND SOUTHERN CWA BORDER. A GRADUAL
SHIFT IN THE 500MB HIGH CENTER FURTHER TO THE NORTH ACROSS THE
INTERMOUNTAIN WEST COULD ALLOW FOR MORE INVERTED TROUGHING TO SKIRT
ALONG ITS SOUTHERN PERIPHERY AND RIGHT THROUGH THE SOUTHWEST DURING
THIS TIME FRAME. CONCEPTUALLY WITH THE INCREASE IN THE MOISTURE AND
DEEP EASTERLY FLOW THROUGH THE MID AND UPPER LEVELS OF THE
PROFILE...STORM ACTIVITY HAS THE POTENTIAL TO INCREASE ACROSS
ARIZONA FOR SUNDAY AND CWA-WIDE BY MONDAY AS MOISTURE REACHES BEYOND
THE CO RIVER VALLEY. ELEVATED DEWPOINTS AND EASTERLY FLOW ALOFT
WARRANT CONTINUED ABOVE CLIMO POPS FOR NEXT WEEK...HOWEVER ONE DAY`S
FORECAST MAY BE OFFSET BY THE PREVIOUS NIGHT`S ACTIVITY. DAYTIME
TEMPERATURES WILL GRADUALLY TREND COOLER AND CLOSER TOWARD SEASONAL
NORMALS WHILE THE OVERNIGHTS WILL REMAIN ON THE MILD TO WARM SIDE.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL... OUTFLOWS
FROM DECAYING THUNDERSTORMS OVER THE TUCSON AREA ARE EXPECTED TO
REACH THE GREATER PHX AREA DURING THE NEXT HOUR OR TWO...WITH A
PERIOD OF GUSTY SE-LY WINDS LIKELY AS THE BOUNDARY PASSES THROUGH
EACH TAF SITE. AS THIS POINT...IT DOES NOT APPEAR THAT THE WINDS
WILL BE STRONG ENOUGH TO PRODUCE SIGNIFICANT BLOWING DUST. WINDS
WILL THEN REVERT BACK TO TYPICAL DIURNAL DIRECTIONS/SPEEDS AT ALL OF
THE PHOENIX TAF SITES LATER TONIGHT AND ON FRIDAY. SCT-BKN MID TO
HIGH LEVEL CIGS TO PREVAIL THROUGH THE TAF PERIOD AT ALL OF THE
TERMINALS.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
MOSTLY CLEAR SKIES AND LIGHT/DIURNALLY DRIVEN WINDS EXPECTED AT BOTH
TAF SITES THROUGH FRIDAY.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY...
STORM CHANCES WILL BE CONFINED TO THE HIGHER TERRAIN LOCATIONS OF
EASTERN ARIZONA TO FINISH OUT THE WEEK BEFORE STORM CHANCES EXPAND
ACROSS THE AREA EARLY NEXT WEEK. STRONG WINDS AND LIGHTNING WILL
GRADUALLY BECOME MORE LIKELY DURING THIS TIME FRAME WITH WETTING
RAINS TENDING TO BE LOCALIZED. ACCORDINGLY...HUMIDITIES WILL BE
TRENDING UPWARD.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER CONDITIONS
ACCORDING TO STANDARD OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...PERCHA/CB/NOLTE
AVIATION...LEINS
FIRE WEATHER...DEWEY
AREA FORECAST DISCUSSION
NWS TUCSON AZ
925 PM MST THU JUN 25 2015
.SYNOPSIS...THUNDERSTORM CHANCES WILL INTO EARLY NEXT WEEK AS
MOISTURE INCREASES ACROSS THE AREA. HEAVIER RAINFALL SHOULD OCCUR
ACROSS VALLEY LOCATIONS...AND DAYTIME TEMPERATURES WILL TREND CLOSER
TO NORMAL BY EARLY NEXT WEEK.
&&
.DISCUSSION...SCATTERED SHOWERS HAVE DEVELOPED DURING ABOUT THE PAST
30-60 MINUTES ACROSS SRN GRAHAM/NRN COCHISE COUNTIES EAST TO
NORTHEAST OF TUCSON. THE REST OF SE ARIZONA WAS VOID OF PRECIP
ECHOES AS PER KEMX WSR-88D AT THIS TIME. LATEST HRRR SUGGESTS THE
BULK OF THIS RAINFALL WILL DISSIPATE BY AROUND DAYBREAK FRI. FOR THE
REST OF TONIGHT...HAVE MAINTAINED A SLIGHT CHANCE OF SHOWERS/TSTMS
MAINLY FROM TUCSON EWD/SWD TO THE NEW MEXICO/INTERNATIONAL BORDERS.
CLEARING SKIES MAY THEN OCCUR AROUND DAYBREAK FRI FOLLOWED BY
ANOTHER ROUND OF SHOWERS/TSTMS MAINLY EAST TO SOUTH OF TUCSON FRI
AFTERNOON/EVENING.
PLEASE REFER TO THE ADDITIONAL SECTIONS FOR FURTHER DETAIL.
&&
.AVIATION...VALID THRU 27/06Z.
SCATTERED -SHRA WITH ISOLATED -TSRA WILL MOSTLY END AROUND 26/12Z.
ISOLATED TO SCATTERED -TSRA/-SHRA WILL RETURN MAINLY EAST TO SOUTH
OF KTUS FRIDAY AFTERNOON AND EVENING. BRIEF WIND GUSTS OF 40-50 KTS
SHOULD ACCOMPANY THE STRONGER TSRA FRIDAY AFTERNOON. OTHERWISE...
CLOUD DECKS WILL GENERALLY BE AT OR ABOVE 10K FT AGL...AND SURFACE
WIND BE LESS THAN 10 KTS. AVIATION DISCUSSION NOT UPDATED FOR TAF
AMENDMENTS.
&&
.FIRE WEATHER...ADEQUATE MOISTURE WILL RESULT IN DAILY THUNDERSTORM
ACTIVITY INTO NEXT WEEK. FRIDAY MAY BE A BIT LESS ACTIVE DAY BUT
THIS WEEKEND AND MONDAY SHOULD SEE SUBSTANTIAL STORM COVERAGE.
INITIAL THUNDERSTORM HAZARDS WILL BE STRONG GUSTY OUTFLOWS AND DRY
LIGHTNING UNTIL MOISTURE BECOMES MORE ENTRENCHED THIS WEEKEND. WIND
GUSTS OF 35-45 MPH WILL BE FAIRLY COMMON WITH THE POTENTIAL FOR THE
STRONGEST AFTERNOON AND EARLY EVENING STORMS TO PRODUCE WINDS IN
EXCESS OF 50 MPH.
&&
.PREVIOUS DISCUSSION...FOR FRIDAY...HIGH PRESSURE WILL BRIEFLY
STRENGTHEN AND RECONSOLIDATE SLIGHTLY OVER NORTHERN ARIZONA WHICH
WILL RESULT IN LESSER CHANCES OF SHOWERS AND THUNDERSTORMS FROM
TUCSON NORTH AND WEST WITH THE BULK OF THE STORMS SOUTH AND EAST OF
TUCSON AND ESPECIALLY NEAR THE NEW MEXICO AND INTERNATIONAL BORDERS.
FOR THIS WEEKEND INTO NEXT WEEK...HIGH PRESSURE ALOFT WILL BE
LOCATED OVER THE GREAT BASIN RESULTING IN FAVORABLE EASTERLY FLOW
WITH CONSIDERABLE MOISTURE. THERE WILL BE EMBEDDED WEAK INVERTED
TROUGHS IN THE FLOW TO OUR SOUTH THAT WILL LIKELY ENHANCE
CONVECTION...PERHAPS SUNDAY INTO MONDAY BUT THESE ARE SMALL SCALE
FEATURES THAT THE MODELS WILL HAVE A HARD TIME PICKING UP ON THIS
FAR OUT. BOTTOM LINE IS PLENTY OF MOISTURE TO WORK WITH FOR AN
OVERALL MID GRADE MONSOON THIS WEEKEND INTO NEXT WEEK BUT CERTAINLY
ACTIVE FOR LATE JUNE.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
915 PM MST THU JUN 25 2015
.SYNOPSIS...
ABOVE NORMAL TEMPERATURES WILL PERSIST ACROSS THE REGION THROUGH THE
WEEKEND. THUNDERSTORMS ARE EXPECTED TO BE LARGELY CONFINED TO THE
WHITE MOUNTAINS AND SOUTHEAST ARIZONA THROUGH SATURDAY...BUT WITH
STRONG WINDS AND AREAS OF BLOWING DUST POSSIBLE ON THE LOWER DESERTS
DUE TO DISTANT STORMS. MORE HUMID AIR IS ANTICIPATED TO OVERSPREAD
THE REGION BEGINNING LATER IN THE WEEKEND WITH STORM CHANCES
EXPANDING TO MANY LOWER DESERT LOCATIONS BY EARLY NEXT WEEK. THE
INCREASE IN MONSOON STORM ACTIVITY COULD LEAD TO SLIGHTLY COOLER
DAYTIMES BUT WARMER OVERNIGHTS.
&&
.DISCUSSION... AS EXPECTED...TODAY WAS NOT QUITE AS ACTIVE ACROSS
OUR CWA THEN WHAT WE SAW YESTERDAY...WHEN A WEAK INVERTED TROF
HELPED TO TRIGGER THUNDERSTORM ACTIVITY ACROSS THE HIGHER TERRAIN OF
SOUTH-CENTRAL ARIZONA...WHICH GENERATED AN OUTFLOW BOUNDARY THAT
MOVED WESTWARD INTO THE GREATER PHOENIX AREA. ALTHOUGH A FEW STORMS
DID AGAIN DEVELOP OVER GILA COUNTY...TODAY/S ACTIVITY WAS MORE
FOCUSED OVER SE AZ...WITH TUCSON INTERNATIONAL AIRPORT SEEING WIND
GUSTS UP TO 60 MPH FROM NEARBY THUNDERSTORMS. ALTHOUGH OUTFLOWS FROM
THE STORMS OVER THE TUCSON AREA DID ATTEMPT TO MOVE NORTHWARD...THEY
PRETTY MUCH DISSIPATED WELL TO THE SOUTH OF OUR CWA. ANOTHER AREA
THAT ACTUALLY SAW A FEW SPRINKLES TODAY...WITH CONSIDERABLE
CLOUDINESS THAT KEPT HIGHS DOWN AT/BELOW 100 WAS THE YUMA AREA. THE
CLOUDINESS OVER THAT AREA IS NOW BEGINNING TO THIN/CLEAR AS THE
MOISTURE PLUME IS PUSHED OFF TO THE WEST. AS FAR AS THE FORECAST FOR
THE REST OF THE NIGHT AND EARLY FRIDAY IS CONCERNED...IT SHOULD BE
PRETTY QUIET...WITH THE LATEST HRRR KEEPING CONVECTIVE ACTIVITY
PRETTY MUCH OVER THE TUCSON CWA. OTHER THAN SOME MINOR ADJUSTMENTS
TO HOURLY TRENDS...INHERITED FORECASTS ARE LOOKING GOOD.
&&
.PREVIOUS DISCUSSION... STRONG HIGH PRESSURE ALOFT WAS SITUATED OVER
THE DESERT SOUTHWEST EARLY THIS AFTERNOON WITH THE UPPER HIGH CENTER
LOCATED OVER FAR NCENTRAL ARIZONA NEAR THE UTAH BORDER. H5 HEIGHTS
REMAINED HIGH ACROSS SRN AZ...NEAR 592DM AND UNDER MOSTLY SUNNY
SKIES THE CENTRAL DESERTS WERE RAPIDLY CLIMBING TOWARDS 110 DEGREES
AS OF 1 PM. SURFACE DEWPOINTS OVER THE CENTRAL DESERTS WERE ELEVATED
EARLY THIS AFTERNOON COMPARED TO 24 HOURS AGO...RANGING FROM UPPER
40S TO MID 50S...BUT THEY WILL LIKELY DROP ANOTHER FEW DEGREES BY
LATE AFTERNOON AND WILL BE TOO LOW TO SUPPORT DESERT CONVECTION.
RADAR AS WELL AS IR/LIGHTNING IMAGERY SHOWED A FEW STORMS DEVELOPING
OVER FAR SERN AZ AND THE WHITE MOUNTAINS BUT LITTLE WAS HAPPENING
CONVECTIVELY OVER SRN GILA COUNTY. PART OF THE REDUCTION IN
CONVECTION IS DUE TO THE COOLER TEMPS TODAY COMPARED TO YESTERDAY.
FOR TONIGHT THROUGH FRIDAY NIGHT...THE STRONG UPPER HIGH WILL REMAIN
CENTERED TO OUR NORTH...GIVING THE SRN DESERTS A WEAK ELY STEERING
FLOW MOSTLY AOB 15KT. MODEL GUIDANCE IS CONSISTENT IN CALLING FOR
LIMITED MOISTURE AND INSTABILITY OVER THE LOWER DESERTS...WITH CAPE
VALUES MOSTLY BELOW 200J/KG. THE STRENGTH OF THE UPPER HIGH WILL ACT
TO CAP CONVECTION SOMEWHAT OVER OUR AREA WITH THE ONLY REAL THREAT
FOR STORMS TO FOCUS OVER THE HIGHER TERRAIN OF SOUTHERN GILA COUNTY.
ESSENTIALLY WE ARE LOOKING AT LOW GRADE MONSOON CONDITIONS TONIGHT
THROUGH FRIDAY NIGHT WITH SLIGHT CHANCES ACROSS ZONE 24 AND SINGLE
DIGIT POPS ELSEWHERE. GIVEN THE RATHER LOW GRADE CONDITIONS...THE
THREAT OF BLOWING DUST INTO NRN PINAL COUNTY OR THE EAST VALLEY WILL
BE MINIMAL AS WELL. LOW GRADE MONSOON CONDITIONS WILL ALSO CONTINUE
DURING THE DAY ON SATURDAY.
UNDER PARTLY TO MOSTLY SUNNY SKIES FRIDAY INTO SATURDAY...HIGH TEMPS
WILL STAY WELL ABOVE SEASONAL NORMALS WITH MOST OF THE HOTTER
DESERTS REACHING OR EXCEEDING 110 DEGREES. WE EXPECT HIGHS TO STAY
SLIGHTLY BELOW EXCESSIVE HEAT WARNING CRITERIA HOWEVER.
OVERNIGHT SATURDAY INTO SUNDAY A DEEPER MOISTURE FROM
THE EAST WILL OVERSPREAD THE AREA...INCREASING CHANCES FOR SHOWER
AND THUNDERSTORM ACTIVITY FOR THE LATE WEEKEND AND EARLY NEXT WEEK.
FLOW THROUGH THE 700-500MB LAYER BECOMES A BIT MORE UNIDIRECTIONAL
FROM THE SOUTHEAST AND ELEVATED IN VELOCITY ACROSS SOUTHEAST AZ
FIRST ON SUNDAY BUT THEN EXPANDS INTO SOUTH-CENTRAL AND SOUTHWEST AZ
LATER INTO THE DAY ON MONDAY. PWATS NEAR THE 1.25 INCH MARK AND
850MB DEWPOINTS ARE PROGGED INTO THE 8-10C RANGE ACROSS THE NORTHERN
CWA TIER AND 10C+ ACROSS SW AZ AND SOUTHERN CWA BORDER. A GRADUAL
SHIFT IN THE 500MB HIGH CENTER FURTHER TO THE NORTH ACROSS THE
INTERMOUNTAIN WEST COULD ALLOW FOR MORE INVERTED TROUGHING TO SKIRT
ALONG ITS SOUTHERN PERIPHERY AND RIGHT THROUGH THE SOUTHWEST DURING
THIS TIME FRAME. CONCEPTUALLY WITH THE INCREASE IN THE MOISTURE AND
DEEP EASTERLY FLOW THROUGH THE MID AND UPPER LEVELS OF THE
PROFILE...STORM ACTIVITY HAS THE POTENTIAL TO INCREASE ACROSS
ARIZONA FOR SUNDAY AND CWA-WIDE BY MONDAY AS MOISTURE REACHES BEYOND
THE CO RIVER VALLEY. ELEVATED DEWPOINTS AND EASTERLY FLOW ALOFT
WARRANT CONTINUED ABOVE CLIMO POPS FOR NEXT WEEK...HOWEVER ONE DAY`S
FORECAST MAY BE OFFSET BY THE PREVIOUS NIGHT`S ACTIVITY. DAYTIME
TEMPERATURES WILL GRADUALLY TREND COOLER AND CLOSER TOWARD SEASONAL
NORMALS WHILE THE OVERNIGHTS WILL REMAIN ON THE MILD TO WARM SIDE.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
STORMS EXPECTED AGAIN THIS AFTERNOON BUT THERE SHOULD BE MUCH LESS
COVERAGE AND MUCH LOWER CHANCES OF OUTFLOWS MAKING THEIR WAY THROUGH
THE METRO AREA. THUS...GOING WITH TYPICAL DIURNAL WINDS AT ALL
PHOENIX TAF SITES. LIKELY LOOKING AT SOME AFTERNOON/EARLY EVENING
GUSTINESS OUT OF THE WEST EVENTUALLY TURNING AROUND OUT OF THE EAST
RIGHT BEFORE 12Z FRIDAY.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
MOSTLY CLEAR SKIES AND LIGHT/DIURNALLY DRIVEN WINDS EXPECTED AT BOTH
TAF SITES THROUGH THURSDAY.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY...
STORM CHANCES WILL BE CONFINED TO THE HIGHER TERRAIN LOCATIONS OF
EASTERN ARIZONA TO FINISH OUT THE WEEK BEFORE STORM CHANCES EXPAND
ACROSS THE AREA EARLY NEXT WEEK. STRONG WINDS AND LIGHTNING WILL
GRADUALLY BECOME MORE LIKELY DURING THIS TIME FRAME WITH WETTING
RAINS TENDING TO BE LOCALIZED. ACCORDINGLY...HUMIDITIES WILL BE
TRENDING UPWARD.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER CONDITIONS
ACCORDING TO STANDARD OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...PERCHA/CB/NOLTE
AVIATION...LEINS
FIRE WEATHER...DEWEY
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
457 AM EDT FRI JUN 26 2015
.SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS ARE SHOWING THE BEGINNING
STAGES OF A SIGNIFICANT UPPER LEVEL PATTERN AMPLIFICATION THAT
WILL COMPLETE DURING THE UPCOMING WEEKEND. CURRENT PATTERN
CONSISTS OF RIDGING OVER THE INTER-MOUNTAIN WEST INTO SOUTHWEST
CANADA...WITH THE NORTHERN STREAM FLOW THEN DIPPING SOUTHWARD
ACROSS THE UPPER MIDWEST AND OHIO VALLEY. AS MENTIONED
ABOVE...THIS IS JUST THE BEGINNING TO A MUCH GREATER
AMPLIFICATION. SHORTWAVE ENERGY CURRENTLY MOVING THROUGH THE
NORTHERN PLAINS IS FORECAST TO SHARPEN AND EVENTUALLY CUT OFF AS
IT MOVES EASTWARD DURING THE NEXT 24-30 HOURS. THIS WILL RESULT
IN AN UNUSUALLY PATTERN FOR THE END OF JUNE SUPPORTIVE OF A DEEP
SURFACE CYCLONE OVER THE OHIO VALLEY BY LATE SATURDAY.
CURRENTLY WE FIND THE SUBTROPICAL SURFACE RIDGE AXIS IN A POSITION
ACROSS THE CENTRAL FLORIDA PENINSULA/EASTERN GULF OF
MEXICO...HOWEVER THIS RIDGE WILL BE SETTLING SOUTHWARD TODAY INTO
TONIGHT AS THE AMPLIFICATION EVOLVES INTO THE EASTERN CONUS.
CONDITIONS ARE CURRENTLY QUIET AND DRY ACROSS THE FORECAST
AREA...AND OTHER THAN A FEW ISOLATED SHOWERS UP TOWARD LEVY
COUNTY...ANTICIPATE THESE QUIET CONDITIONS TO CONTINUE FOR AT
LEAST A FEW HOURS AFTER SUNRISE. THEREAFTER...THE TYPICAL DAILY
SEA BREEZE AND ASSOCIATED SCT CONVECTION WILL BEGIN TO EVOLVE.
&&
.SHORT TERM...
TODAY...
AS THE SURFACE RIDGE AXIS SLOWLY SETTLES SOUTHWARD TODAY...THIS
WILL PRESENT OUR FORECAST AREA WITH A GENERAL LIGHT SOUTHWESTERLY
LOW LEVEL FLOW REGIME...WITH THE MOST DEFINED SOUTHWEST FLOW
ACROSS THE NATURE COAST ZONES. SOUTHWEST FLOW REGIME DAYS TEND TO
RESULT IN A SCATTERING OF STORMS ALONG THE COAST DURING THE LATE
MORNING/EARLY AFTERNOON HOURS...WITH THE MAJORITY OF THE
CONVECTION THEN MIGRATING RAPIDLY INLAND WITH THE SEA BREEZE FOR
THE LATER AFTERNOON AND EVENING HOURS. WILL USE THIS MODEL FOR THE
TEMPORAL AND SPATIAL RAINFALL CHANCES TODAY. WILL HAVE THE
GREATEST PUSH INLAND OVER THE NORTHERN ZONES...WITH A SLOWER
INLAND PROPAGATION DOWN TOWARD LEE/CHARLOTTE COUNTIES IN CLOSER
PROXIMITY TO THE RIDGE AXIS. THE HIGHEST COVERAGE OF STORMS TODAY
WILL LIKELY BE DURING THE LATE AFTERNOON/EARLY EVENING OVER THE
SOUTH-CENTRAL ZONES OF POLK/HIGHLANDS/HARDEE/DESOTO COUNTIES.
AWAY FROM THE STORMS...TYPICAL SUMMER CONDITIONS ARE EXPECTED WITH
PARTLY SUNNY SKIES AND TEMPERATURES CLIMBING TO WITHIN A COUPLE
DEGREES OF 90.
TONIGHT...CONVECTION LIKELY LINGERS INTO THE LATE EVENING HOURS
ACROSS EASTERN POLK/HIGHLANDS COUNTIES...WHILE THE REMAINDER OF
THE FORECAST AREA SEE DRIER CONDITIONS. AFTER MIDNIGHT...WOULD
EXPECT MOST DRY CONDITIONS FOR ALL INLAND ZONES...ALTHOUGH A FEW
LATE NIGHT SHOWERS ARE CLIMO FAVORED WITHIN THE SOUTHWEST FLOW OFF
THE GULF OF MEXICO AT THE IMMEDIATE COAST.
SATURDAY...THE FORECAST AREA WILL RESIDE BETWEEN THE SUBTROPICAL
RIDGE AXIS TO OUR SOUTH...AND AN APPROACHING COLD FRONT DROPPING
THROUGH THE SOUTHEAST CONUS TO OUR NORTH. THE ENTIRE REGION WILL
SEE A DEFINED SOUTHWEST FLOW FOR THE DAYLIGHT HOURS OF
SATURDAY...SUGGESTING THE SEA-BREEZE WILL REMAIN LESS DEFINED AND
ALSO RAPIDLY PROGRESS INLAND TOWARD THE EASTERN PORTION OF THE
STATE. THIS PATTERN FAVORS MOST OF THE AFTERNOON/EVENING STORMS TO
OCCUR TO THE EAST OF OUR FORECAST ZONES. IN ADDITION TO THE
PATTERN...THE NWP ENSEMBLES ARE ALL SUGGESTING SOME MUCH DRIER AIR
ARRIVING IN THE MID-LEVELS FROM THE WEST DURING THE DAY. THE
COMBINATION OF THESE TWO FACTORS SHOULD KEEP RAIN CHANCES BELOW
CLIMO NORMS FOR JUST ABOUT ALL. RAIN CHANCES ACTUALLY LOOK QUITE
LOW DURING THE AFTERNOON HOURS ALONG AREA BEACHES. HOWEVER...IF
HEADING TO THE BEACHES...KEEP IN MIND THAT THE STEADY SOUTHWEST
FLOW WILL BEGIN TO INCREASE THE RISK FOR STRONGER AND MORE
FREQUENT RIP CURRENTS BY THE SECOND HALF OF THE DAY. THIS THREAT
FOR ENHANCED RIP CURRENTS WILL CONTINUE THROUGH SUNDAY AS WELL.
&&
.LONG TERM (SATURDAY NIGHT - THURSDAY)...
BY THE START OF THE LONG TERM PERIOD...A DEEP UPPER LEVEL TROUGH
WILL ALREADY BE IN PLACE OVER THE EASTERN CONUS...AND WILL HOLD IN
PLACE THROUGH THE START OF THE WORK WEEK. AT THE SURFACE...A LOW
PRESSURE SYSTEM CENTERED JUST SOUTH OF THE EASTERN GREAT LAKES WILL
LIFT NORTHEAST INTO CANADA...DRAGGING A WEAK COLD FRONT INTO
NORTHERN FLORIDA ON SUNDAY...WHERE IT WILL STALL OUT. THE SURFACE
RIDGE AXIS WILL REMAIN SOUTH OF FLORIDA SUNDAY AND MONDAY...SETTING
UP SOUTHWESTERLY FLOW ACROSS THE FORECAST AREA. ALTHOUGH SUNDAY WILL
START OUT WITH A PATCH OF DRY AIR OVER MUCH OF THE FORECAST
AREA...THE ENHANCED SOUTHEASTERLY FLOW SOUTH OF THE FRONTAL BOUNDARY
WILL BRING DEEP MOISTURE BACK INTO THE REGION...ALLOWING FOR
SCATTERED TO NUMEROUS THUNDERSTORMS SUNDAY AFTERNOON THROUGH
MONDAY...WITH THE HIGHEST CHANCES FARTHER NORTH.
TUESDAY THROUGH THURSDAY...THE UPPER LEVEL TROUGH WILL PULL AWAY
FROM FLORIDA...ALLOWING THE COLD FRONT TO DEGRADE AND THE SURFACE
RIDGE AXIS TO LIFT BACK NORTH TO AROUND THE INTERSTATE 4 CORRIDOR.
THIS WILL BRING ABOUT A MORE TYPICAL SUMMERTIME PATTERN...WITH LIGHT
GRADIENT FLOW AND SCATTERED THUNDERSTORMS...MOSTLY DURING THE
AFTERNOON AND EARLY EVENING HOURS ALONG SEA BREEZE BOUNDARIES.
&&
.AVIATION...
VFR CONDITIONS ARE OBSERVED EARLY THIS MORNING ACROSS WEST-CENTRAL
AND SOUTHWEST FLORIDA. OVERALL EXPECTING A TYPICAL SUMMER TYPE DAY
FOR THE FORECAST TERMINALS WITH VFR CONDITIONS PERSISTING OUTSIDE
OF SCATTERED MAINLY AFTERNOON/EVENING THUNDERSTORMS. SCATTERED
STORMS WILL BE MOST LIKELY FOR KTPA/KPIE/KSRQ DURING THE LATE
MORNING OR EARLY AFTERNOON...WITH STORMS THEN MOVING INLAND
TOWARD KLAL. FURTHER SOUTH...A SCATTERING OF STORMS DURING THE
AFTERNOON SHOULD PUSH EAST OF KPGD/KFMY/KRSW BY THE EVENING HOURS.
&&
.MARINE...
HIGH PRESSURE ACROSS THE EASTERN GULF OF MEXICO WILL SETTLE SOUTH
THROUGH SATURDAY AS A COLD FRONT DROPS INTO THE SOUTHEASTERN
STATES AND STALLS JUST NORTH OF THE AREA ON SUNDAY. WINDS AND SEAS
WILL REMAIN LOW TONIGHT...HOWEVER THE GRADIENT WILL TIGHTEN THIS
WEEKEND AHEAD OF THE FRONT RESULTING IN MORE STEADY SOUTHWEST
FLOW AND HIGHER SEAS. THE WINDS AND SEAS WILL GENERALLY BE HIGHEST
TO THE NORTH OF TARPON SPRINGS. WINDS NORTH OF TARPON SPRINGS
MAY APPROACH CAUTIONARY LEVELS AT TIMES THIS WEEKEND. SHOWERS AND
THUNDERSTORMS WILL ALSO BECOME MORE NUMEROUS THIS WEEKEND...MAINLY
TO THE NORTH OF TARPON SPRINGS.
&&
.FIRE WEATHER...
NO SIGNIFICANT FIRE WEATHER CONCERNS ARE EXPECTED THROUGH THE
UPCOMING WEEKEND AS RELATIVE HUMIDITY VALUES REMAIN ABOVE CRITICAL
LEVELS. SHOWERS AND THUNDERSTORM WILL TAKE ON A TYPICAL PATTERN
TODAY...BUT IT NOW APPEARS THAT DRIER AIR ARRIVING ALOFT WILL KEEP
CONVECTIVE ACTIVITY BELOW NORMAL FOR SATURDAY. A FRONT WILL STALL
JUST NORTH OF THE REGION SUNDAY INTO THE EARLY PORTION OF NEXT
WEEK BRINGING HIGHER THAN NORMAL RAIN CHANCES TO AREAS NORTH OF
THE INTERSTATE 4 CORRIDOR.
FOG IMPACT...NO WIDESPREAD FOG IMPACTS ARE EXPECTED OVER THE NEXT
SEVERAL DAYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 91 79 91 79 / 40 10 20 10
FMY 92 76 93 77 / 40 20 20 10
GIF 93 75 93 75 / 60 40 30 10
SRQ 89 78 89 78 / 30 20 20 10
BKV 92 74 92 74 / 40 10 20 10
SPG 90 80 91 79 / 30 10 20 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WEATHER...14/MROCZKA
LONG TERM/DECISION SUPPORT...18/FLEMING
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1152 PM CDT THU JUN 25 2015
.SHORT TERM /TONIGHT/...
ISSUED AT 356 PM CDT THU JUN 25 2015
MAIN FORECAST CONCERN WAS FOCUSED ON WEAK SHORTWAVE
CUTTING ACROSS NEBRASKA AND POTENTIALLY BRINGING SOME LOCALLY HEAVY
RAIN TO FAR SOUTHERN IOWA TONIGHT. BOUNDARY LOOKS TO BE SET UP IN
NORTHERN MISSOURI AND POSSIBLY SHIFT NORTH ENOUGH TO THE IOWA BORDER
TONIGHT...BUT HAVE FAIRLY HIGH CONFIDENCE THAT IS THE FARTHEST
EXTENT NORTH IT WILL REACH. DECENT MOISTURE CONVERGENCE ALONG THE
MO/IA BORDER WITH STILL A GOOD ATMOSPHERE FOR EFFICIENT RAIN
PRODUCERS. PRECIPITABLE WATER VALUES AROUND 1.5 INCHES AND WARM
LAYER CLOUD DEPTHS IN THE 3500-3800 METER RANGE. FORWARD PROPAGATION
CORFIDI VECTORS ORIENTED WEST TO EAST PROVIDING SOME TRAINING
POTENTIAL ALONG THE FAR SOUTH. THE 25.19Z HRRR KEEPS MUCH OF THE
HEAVY CONVECTION IN MISSOURI. HOWEVER...INCREASED POPS AND QPF OVER
THE SOUTHERN TIER OF COUNTIES ALONG THE MISSOURI BORDER. OTHER
CONCERN WAS ANOTHER WEAK SHORTWAVE TO PROVIDE SOME ELEVATED SHOWERS
AND ISOLATED THUNDERSTORM OVER THE REMAINDER OF THE FORECAST AREA.
QPF AMOUNTS SHOULD REMAIN UNDER QUARTER OF AN INCH AND THUS LOW
IMPACT ON ANY ONGOING FLOODING
.LONG TERM /FRIDAY THROUGH THURSDAY/...
ISSUED AT 356 PM CDT THU JUN 25 2015
A MUCH...MUCH QUIETER 7 DAYS AHEAD IN THIS LONG TERM FCST PERIOD.
WATER VAPOR IMAGERY PICKING UP ON HIGH PRESSURE COMING ONSHORE NEAR
THE OREGON COASTLINE. THIS HIGH PRESSURE WILL HAVE SIGNIFICANT
INFLUENCE ON OUR WEATHER MUCH OF NEXT WEEK.
FRIDAY MORNING...MODELS PICKING UP ON A SHORTWAVE CONTINUING THROUGH
SOUTHERN IA/NORTHERN MO. ISENTROPIC LIFT PERSISTING INTO 12Z AS THIS
SYSTEM WILL LIKELY BE CLIPPING AT LEAST THE SOUTHERN TWO TO THREE
TIERS OF COUNTIES IN IA. WITH YESTERDAY/S BOUNDARY LINGERING IN
NORTHERN MO...A LOT OF THE MOISTURE FROM THURSDAY/S SYSTEM STILL
AROUND. MODELS FOCUSING IN ON PWATS BTX 1.5 AND 1.75 INCHES...WHICH
IS AROUND +1 TO +2 STD DEV. GOOD SUPPORT ALOFT AS MID-LEVEL Q-VECTOR
CONV PRESENT TO INCREASE LIFT. 0-6KM MIXING RATIOS AROUND 7 G/KG
WHICH IS DECENT ENOUGH. OVERALL SOUNDING PROFILE MUCH LESS SATURATED
THAN MOST OF THIS WEEK...SO THIS SYSTEM WILL NOT BE THE MOST
EFFICIENT IN RAIN PRODUCTION.
FRI AFTERNOON TEMPS...850MB TEMPS AROUND 12C IN OUR EAST AND 14C IN
OUR WEST...ABOUT -1 TO -2 STD DEV. THURSDAY/S 850 MB TEMPS WERE
AROUND 14C NE TO 17C SW. AM EXPECTING SUNSHINE TO BREAK
THROUGH...BUT NOT A LOT...SO HAVE KEPT TEMPS IN THE MID 70S.
FRI AFTERNOON THUNDERSTORM POTENTIAL...0-6KM MUCAPE VALUES BTX 700
AND 1000 J/KG WHICH WHICH IS MINIMAL. 0-6KM BULK SHEAR NEAR
30KTS...ALSO MINIMAL. LCL HEIGHTS ABOVE 1000M. OVERALL SOUNDING
PROFILE SUGGESTS ANYTHING THAT FORMS WOULD BE ELEVATED. THUS
OVERALL...AM EXPECTING NIL SVR/TOR THREAT FRI PM AND THERE MAY BE A
FEW SHORT LIVED NON-SEVERE STORMS PRIMARILY IN OUR NW.
FOR SATURDAY NIGHT INTO SUNDAY EVENING...MODELS CONSISTENT WITH
PROPAGATING AN AREA OF LOW PRESSURE FROM NW MINNESOTA INTO SE
MINNESOTA. A WEAK COLD FRONT WILL BE ATTACHED TO THIS AND PUSHING
THROUGH IA DURING THE DAYTIME. THE 12Z GFS IS A FAST OUTLIER WITH
THIS SYSTEM AS IT PLACES THE BOUNDARY EAST OF OUR CWA BY 12-15Z SUN.
HAVE MAINLY DISREGARDED THE GFS AND WENT WITH AN AVERAGE OF OTHER
MODELS. PWATS JUMP FROM AROUND 1.25 TO 1.5 INCHES AND 0-6KM MUCAPE
VALUES ARE AROUND 400 TO 600 J/KG. POSITION OF FRONT DURING PEAK
DAYTIME HEATING IMPORTANT FOR SVR POTENTIAL. AS OF NOW...ALL SIGNS
POINT TO THIS BOUNDARY BEING WELL EAST OF THE CWA BY DAYTIME
HEATING.
FOR MONDAY AND THE REST OF THIS LONG TERM FCST PERIOD...PERSISTENCE
BECOMES A GOOD FORECAST THROUGH MID-WEEK. AN UPPER LEVEL TROUGH OVER
THE NORTHEASTERN US AND AN UPPER LEVEL RIDGE OVER THE MOUNTAIN WEST
WILL KEEP THE DMX CWA IN NORTHWESTERLY FLOW SEEMING INTO THE NEXT
THU/FRI/SAT TIMEFRAME. A HUGE THERMAL RIDGE WILL BUILD OVER THE
MOUNTAIN WEST COINCIDENT WITH THE UPPER LEVEL HIGH. THE RIDGE WILL
STAY TO OUR WEST AND 850 MB TEMPS WILL BE IN THE DMX CWA WILL BE
AROUND 15C TO OUR EAST AND 18C TO THE WEST. MODELS HINTING AT
THERMAL RIDGE CRASHING DOWN INTO IA SOMETIME LATER IN THE
WEEK...BRINGING A RETURN TO POP CHANCES TO THE AREA.
&&
.AVIATION...26/06Z
ISSUED AT 1152 PM CDT THU JUN 25 2015
AN UPPER LEVEL WAVE WILL PUSH INTO IA OVERNIGHT THROUGH FRIDAY
MORNING LOWERING CIGS TO OCNL MVFR IN PRECIP. SCT SHRA/TSRA WILL
OCCUR WITH THIS FEATURE AND WHILE MOST LOCATIONS WILL SEE
SOMETHING...IT IS NOT EXPECTED TO BE WIDESPREAD. THE BEST LOCATIONS
TO SEE STORMS WILL BE ACROSS FAR SOUTHERN IA...MAINLY AFFECTING
KOTM. A LINE OF STORMS ACROSS MO/KS AND INTO NE WILL SHIFT A LITTLE
NORTH AFFECTING FAR SRN IA. MVFR CIGS WILL BE MOST PREVALENT ACROSS
THIS AREA. AS THE UPPER WAVE PASSES EAST PRECIP CHANCES WILL WANE
AFT 18Z THOUGH SOME SPOTTY SHRA MAY PERSIST. ALL LOCATIONS WILL CLR
AFT 21Z THROUGH THE REMAINDER OF THE TAF PERIOD.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...KOTENBERG
AVIATION...FAB
AREA FORECAST DISCUSSION
NWS JACKSON KY
141 AM EDT FRI JUN 26 2015
.UPDATE...
ISSUED AT 141 AM EDT FRI JUN 26 2015
GIVEN ONGOING CONVECTION OVERNIGHT AND STORMS THURSDAY PRODUCING
HEAVY RAINFALL HAVE OPTED TO ISSUE A FLASH FLOOD WATCH THROUGH
THIS EVENING. DID UPDATE GRIDS AND GRIDS SENT TO NDFD.
UPDATE ISSUED AT 1205 AM EDT FRI JUN 26 2015
QUICK UPDATE TO REFRESH THE T/TD GRIDS AND TO REMOVE THE SEVERE
THUNDERSTORM WATCH. EXPECT SCATTERED STORMS TO CONTINUE THROUGHOUT
THE NIGHT BUT THE SITUATION SEEMS TO HAVE TRANSITIONED TO MORE OF
A HYDRO ISSUE...SO WILL HAVE TO KEEP AN EYE ON STORMS UPSTREAM.
SENT UPDATED GRIDS TO NDFD AND WEB SERVERS.
UPDATE ISSUED AT 935 PM EDT THU JUN 25 2015
SHOWERS AND STORMS CONTINUE ACROSS NORTHEASTERN KENTUCKY THIS
EVENING...WITH MOST OF THEM PRODUCING HEAVY RAINFALL AND FREQUENT
LIGHTNING. STORMS EARLIER THIS AFTERNOON PRODUCED UP TO QUARTER
SIZED HAIL...AND THIS REMAINS POSSIBLE TONIGHT AS WELL.
SOME PATCHY FOG/MIST HAS ALREADY SET IN AT JKL DUE TO THE
MULTIPLE ROUNDS OF RAIN THIS EVENING...SO HAVE ADDED IN PATCHY
VALLEY FOG TO THE NORTHERN HALF OF THE CWA. OTHERWISE...ONLY MINOR
ADJUSTMENTS WERE MADE TO THE T/TD GRIDS TO ALIGN THEM WITH OBS.
SENT UPDATED GRIDS TO NDFD AND WEB SERVERS.
UPDATE ISSUED AT 640 PM EDT THU JUN 25 2015
STRONG TO SEVERE STORMS HAVE FINALLY STARTED TO DEVELOP ACROSS
EASTERN KENTUCKY BUT REMAIN MOSTLY SCATTERED IN NATURE. EXPECT THE
COVERAGE TO INCREASE THROUGHOUT THE EVENING HOURS SINCE THE CAP IS
NOW BROKEN. DECIDED TO BUMP POPS UP TO INCLUDE AT LEAST A SLIGHT
CHANCE POP ACROSS OUR SOUTHERN COUNTIES...AS WELL AS ADJUST T/TD
GRIDS TO ALIGN THEM WITH RECENT OBS. SENT UPDATED GRIDS TO NDFD
AND WEB SERVERS.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 359 PM EDT THU JUN 25 2015
CURRENT CONDITIONS ACROSS THE AREA FEATURE A STATIONARY BOUNDARY
DRAPED ACROSS CENTRAL AND EASTERN KENTUCKY. CURRENT VISIBLE SHOT
ACROSS THE AREA SHOWS SOME BREAKS IN THE CLOUD COVER ACROSS THE
AREA. THIS HAS ALLOWED SOME INCREASED HEATING DESPITE THE CAP
AND LACK OF INSTABILITY FROM THIS MORNINGS MCS. IF THE BREAKS
AND INCREASED HEATING CONTINUES...SOME CONVECTION MAY BEGIN TO
DEVELOP IN THE NEXT COUPLE OF HOURS. THE ISSUE HERE IS IF THE CAP
AT 800MB IS BROKEN. THE HRRR HAS BEEN SLIGHTLY LESS STELLAR
HINTING AT CONVECTION ALL AFTERNOON BUT TO NO AVAIL. SOME SHOWER
ACTIVITY HAS DEVELOPED UPSTREAM IN SOUTHERN IN AND WESTERN KY SO
WILL INTRODUCE SOME POPS INTO EASTERN KENTUCKY AFTER 21Z THIS
AFTERNOON.
HEADING INTO TONIGHT...THE NEXT CLUSTER OF STORMS DEVELOPS AND
BEGINS TO TRACK SOUTHEAST INTO KY. THE FORMATION OF THIS AREA
SHOULD BEGIN IN CENTRAL KY OR EVEN A BIT FURTHER WEST. IT IS WORTH
MENTIONING THAT MODELS HAVE BEEN LESS THAN STELLAR PICKING OUT
THIS DEVELOPMENT. THOUGH WITH TRENDS AND COLLABORATION WITH
NEIGHBORING OFFICES...WILL BE INTRODUCING LIKELY POPS INTO EASTERN
KENTUCKY SHORTLY AFTER 00Z BUT DEVELOPMENT AND A STARTING POINT
FOR CONVECTIVE INITIATION IS A BIT OF A TOUGH CALL.
TOMORROW...A STRONGER WAVE DIPS SOUTH INTO THE LOWER OH VALLEY
CROSSING OVER THE RIDGE OUT WEST AND MAKES FOR AN INTERESTING
SITUATION FOR KY ON FRIDAY EVENING AND FRIDAY NIGHT. WITH
THIS...THE WARM FRONT WITH A STRONG SOUTHERLY SURGE PUSHES
NORTH THROUGH THE AREA. AHEAD OF THIS SHOULD BE STRONG CONVECTION
AND POSSIBLY SEVERE THUNDERSTORMS. EARLY MORNING CONVECTION MAY
HINDER THIS A BIT BUT THE WARM AND MOIST AIR SURGING FROM THE
SOUTH SHOULD MAKE FRIDAY EVENING AND INTO FRIDAY NIGHT QUITE
INTERESTING. WILL MENTION THIS PERIOD IN THE HWO AS THIS WILL
BEGIN AN ACTIVE PERIOD.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 359 PM EDT THU JUN 25 2015
MODELS APPEAR TO BE IN GOOD AGREEMENT WITH MID AND UPPER LEVEL FLOW
THROUGH THE EXTENDED. WE FIND OURSELVES UNDER THE INFLUENCE OF A
HIGH AMPLITUDE PATTERN WITH A MEAN EAST CONUS TROUGH AND WEST CONUS
RIDGE. AS SUCH WE CAN EXPECT BELOW NORMAL TEMPERATURES THROUGH THE
PERIOD AND IN GENERAL AN UNSETTLED WEATHER PATTERN.
MODEL GUIDANCE IS IN GOOD AGREEMENT WITH A POSITIVELY TILTED TROUGH
CUTTING OFF ACROSS THE GREAT LAKES REGION BY EARLY SATURDAY. THIS
FEATURE WILL EVENTUALLY TRACK EAST...BECOMING NEGATIVELY TILTED AS
IT MOVES INTO SOUTHERN NEW ENGLAND STATES SUNDAY. ADDITIONAL
SHORTWAVE ENERGY DIGS OUT A REINFORCING TROUGH OVER OUR REGION BY
MONDAY WHICH ONLY GRADUALLY LIFTS OUT TO THE NORTHEAST BY THE END OF
THE FORECAST WINDOW. BY THEN THERE IS A TENDENCY FOR THE PATTERN TO
BECOME LESS AMPLIFIED AND A BIT MORE ZONALLY ORIENTED AS WESTERN
CONUS RIDGE SHIFTS OUT INTO THE PACIFIC AND ADDITIONAL SHORTWAVE
ENERGY DROPS INTO THE UPPER MIDWEST.
AT THE SURFACE...THE INITIAL TROUGH/CUT OFF LOW WILL AID IN
DEVELOPING A SURFACE LOW ACROSS THE WESTERN OHIO VALLEY AT THE START
OF THE PERIOD. THIS RELATIVELY DEEP AND WELL ORGANIZED SFC LOW WILL
RIDE UP THE OHIO VALLEY OVER THE WEEKEND...WITH A TRAILING COLD
FRONT ADVANCING ACROSS OUR AREA SATURDAY MORNING. ANOTHER FRONTAL
SYSTEM WILL SWEEP THROUGH THE REGION AT THE START OF THE WEEK...LATE
MONDAY INTO TUESDAY. ONCE AGAIN...THIS PATTERN WILL ENSURE BELOW
NORMAL TEMPS THROUGH THE PERIOD WITH HIGHS IN THE MID 70S TO LOWER
80S AND LOWS MAINLY FALLING INTO THE 50S TO LOWER 60S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 141 AM EDT FRI JUN 26 2015
SHOWER AND THUNDERSTORMS CONTINUE TO DEVELOP TONIGHT SO HAVE OPTED
TO KEEP AT LEAST VCTS IN THE TAFS OVERNIGHT. ALSO GIVEN ONGOING
CONVECTION AND MORE OVERNIGHT MANY SITES WILL ALSO SEE POSSIBILITY
OF FOG AND LOWER VIS DURING CONVECTION. IT DOES LOOK LIKE WE WILL
SEE A LULL AS WE MOVE INTO THE DAY ON FRIDAY BEFORE MORE
CONVECTION IS POSSIBLE ONCE AGAIN IN THE AFTERNOON. WINDS WILL
REMAIN LIGHT...EXCEPT UNDER STORMS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR KYZ044-050>052-
058>060-068-069-079-080-083>088-104-106>120.
&&
$$
UPDATE...DJ
SHORT TERM...SHALLENBERGER
LONG TERM...RAY
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
1204 AM EDT FRI JUN 26 2015
.UPDATE...
ISSUED AT 1205 AM EDT FRI JUN 26 2015
QUICK UPDATE TO REFRESH THE T/TD GRIDS AND TO REMOVE THE SEVERE
THUNDERSTORM WATCH. EXPECT SCATTERED STORMS TO CONTINUE THROUGHOUT
THE NIGHT BUT THE SITUATION SEEMS TO HAVE TRANSITIONED TO MORE OF
A HYDRO ISSUE...SO WILL HAVE TO KEEP AN EYE ON STORMS UPSTREAM.
SENT UPDATED GRIDS TO NDFD AND WEB SERVERS.
UPDATE ISSUED AT 935 PM EDT THU JUN 25 2015
SHOWERS AND STORMS CONTINUE ACROSS NORTHEASTERN KENTUCKY THIS
EVENING...WITH MOST OF THEM PRODUCING HEAVY RAINFALL AND FREQUENT
LIGHTNING. STORMS EARLIER THIS AFTERNOON PRODUCED UP TO QUARTER
SIZED HAIL...AND THIS REMAINS POSSIBLE TONIGHT AS WELL.
SOME PATCHY FOG/MIST HAS ALREADY SET IN AT JKL DUE TO THE
MULTIPLE ROUNDS OF RAIN THIS EVENING...SO HAVE ADDED IN PATCHY
VALLEY FOG TO THE NORTHERN HALF OF THE CWA. OTHERWISE...ONLY MINOR
ADJUSTMENTS WERE MADE TO THE T/TD GRIDS TO ALIGN THEM WITH OBS.
SENT UPDATED GRIDS TO NDFD AND WEB SERVERS.
UPDATE ISSUED AT 640 PM EDT THU JUN 25 2015
STRONG TO SEVERE STORMS HAVE FINALLY STARTED TO DEVELOP ACROSS
EASTERN KENTUCKY BUT REMAIN MOSTLY SCATTERED IN NATURE. EXPECT THE
COVERAGE TO INCREASE THROUGHOUT THE EVENING HOURS SINCE THE CAP IS
NOW BROKEN. DECIDED TO BUMP POPS UP TO INCLUDE AT LEAST A SLIGHT
CHANCE POP ACROSS OUR SOUTHERN COUNTIES...AS WELL AS ADJUST T/TD
GRIDS TO ALIGN THEM WITH RECENT OBS. SENT UPDATED GRIDS TO NDFD
AND WEB SERVERS.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 359 PM EDT THU JUN 25 2015
CURRENT CONDITIONS ACROSS THE AREA FEATURE A STATIONARY BOUNDARY
DRAPED ACROSS CENTRAL AND EASTERN KENTUCKY. CURRENT VISIBLE SHOT
ACROSS THE AREA SHOWS SOME BREAKS IN THE CLOUD COVER ACROSS THE
AREA. THIS HAS ALLOWED SOME INCREASED HEATING DESPITE THE CAP
AND LACK OF INSTABILITY FROM THIS MORNINGS MCS. IF THE BREAKS
AND INCREASED HEATING CONTINUES...SOME CONVECTION MAY BEGIN TO
DEVELOP IN THE NEXT COUPLE OF HOURS. THE ISSUE HERE IS IF THE CAP
AT 800MB IS BROKEN. THE HRRR HAS BEEN SLIGHTLY LESS STELLAR
HINTING AT CONVECTION ALL AFTERNOON BUT TO NO AVAIL. SOME SHOWER
ACTIVITY HAS DEVELOPED UPSTREAM IN SOUTHERN IN AND WESTERN KY SO
WILL INTRODUCE SOME POPS INTO EASTERN KENTUCKY AFTER 21Z THIS
AFTERNOON.
HEADING INTO TONIGHT...THE NEXT CLUSTER OF STORMS DEVELOPS AND
BEGINS TO TRACK SOUTHEAST INTO KY. THE FORMATION OF THIS AREA
SHOULD BEGIN IN CENTRAL KY OR EVEN A BIT FURTHER WEST. IT IS WORTH
MENTIONING THAT MODELS HAVE BEEN LESS THAN STELLAR PICKING OUT
THIS DEVELOPMENT. THOUGH WITH TRENDS AND COLLABORATION WITH
NEIGHBORING OFFICES...WILL BE INTRODUCING LIKELY POPS INTO EASTERN
KENTUCKY SHORTLY AFTER 00Z BUT DEVELOPMENT AND A STARTING POINT
FOR CONVECTIVE INITIATION IS A BIT OF A TOUGH CALL.
TOMORROW...A STRONGER WAVE DIPS SOUTH INTO THE LOWER OH VALLEY
CROSSING OVER THE RIDGE OUT WEST AND MAKES FOR AN INTERESTING
SITUATION FOR KY ON FRIDAY EVENING AND FRIDAY NIGHT. WITH
THIS...THE WARM FRONT WITH A STRONG SOUTHERLY SURGE PUSHES
NORTH THROUGH THE AREA. AHEAD OF THIS SHOULD BE STRONG CONVECTION
AND POSSIBLY SEVERE THUNDERSTORMS. EARLY MORNING CONVECTION MAY
HINDER THIS A BIT BUT THE WARM AND MOIST AIR SURGING FROM THE
SOUTH SHOULD MAKE FRIDAY EVENING AND INTO FRIDAY NIGHT QUITE
INTERESTING. WILL MENTION THIS PERIOD IN THE HWO AS THIS WILL
BEGIN AN ACTIVE PERIOD.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 359 PM EDT THU JUN 25 2015
MODELS APPEAR TO BE IN GOOD AGREEMENT WITH MID AND UPPER LEVEL FLOW
THROUGH THE EXTENDED. WE FIND OURSELVES UNDER THE INFLUENCE OF A
HIGH AMPLITUDE PATTERN WITH A MEAN EAST CONUS TROUGH AND WEST CONUS
RIDGE. AS SUCH WE CAN EXPECT BELOW NORMAL TEMPERATURES THROUGH THE
PERIOD AND IN GENERAL AN UNSETTLED WEATHER PATTERN.
MODEL GUIDANCE IS IN GOOD AGREEMENT WITH A POSITIVELY TILTED TROUGH
CUTTING OFF ACROSS THE GREAT LAKES REGION BY EARLY SATURDAY. THIS
FEATURE WILL EVENTUALLY TRACK EAST...BECOMING NEGATIVELY TILTED AS
IT MOVES INTO SOUTHERN NEW ENGLAND STATES SUNDAY. ADDITIONAL
SHORTWAVE ENERGY DIGS OUT A REINFORCING TROUGH OVER OUR REGION BY
MONDAY WHICH ONLY GRADUALLY LIFTS OUT TO THE NORTHEAST BY THE END OF
THE FORECAST WINDOW. BY THEN THERE IS A TENDENCY FOR THE PATTERN TO
BECOME LESS AMPLIFIED AND A BIT MORE ZONALLY ORIENTED AS WESTERN
CONUS RIDGE SHIFTS OUT INTO THE PACIFIC AND ADDITIONAL SHORTWAVE
ENERGY DROPS INTO THE UPPER MIDWEST.
AT THE SURFACE...THE INITIAL TROUGH/CUT OFF LOW WILL AID IN
DEVELOPING A SURFACE LOW ACROSS THE WESTERN OHIO VALLEY AT THE START
OF THE PERIOD. THIS RELATIVELY DEEP AND WELL ORGANIZED SFC LOW WILL
RIDE UP THE OHIO VALLEY OVER THE WEEKEND...WITH A TRAILING COLD
FRONT ADVANCING ACROSS OUR AREA SATURDAY MORNING. ANOTHER FRONTAL
SYSTEM WILL SWEEP THROUGH THE REGION AT THE START OF THE WEEK...LATE
MONDAY INTO TUESDAY. ONCE AGAIN...THIS PATTERN WILL ENSURE BELOW
NORMAL TEMPS THROUGH THE PERIOD WITH HIGHS IN THE MID 70S TO LOWER
80S AND LOWS MAINLY FALLING INTO THE 50S TO LOWER 60S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 804 PM EDT THU JUN 25 2015
SHOWERS AND THUNDERSTORMS HAVE DEVELOPED OVER THE PAST COUPLE OF
HOURS...MAINLY IN AND AROUND THE JKL...SJS...AND SME TAF SITES.
EXPECT THESE STORMS TO GRADUALLY WEAKEN WITH THE LOSS OF DAYTIME
HEATING. BUT ANTICIPATE CIGS/VIS TO LOWER OVERNIGHT TONIGHT DUE TO
LEFTOVER SHOWERS AND FOG DEVELOPMENT...WITH ALTERNATE MIN VIS
POSSIBLE AT THE SJS...SME AND LOZ TAF SITES AND MVFR VIS AT THE
JKL AND SYM TAF SITES. A LULL IN PRECIP DURING THE MORNING HOURS
WILL ALLOW FOR VFR CONDITIONS FOR A TIME ON FRIDAY...BEFORE
AFTERNOON THUNDERSTORM ACTIVITY DEVELOPS ONCE AGAIN. WINDS WILL
REMAIN GENERALLY LIGHT THROUGH THE PERIOD OUTSIDE OF STORMS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JVM
SHORT TERM...SHALLENBERGER
LONG TERM...RAY/DJ
AVIATION...JVM/HAL
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1205 AM CDT FRI JUN 26 2015
.AVIATION...
FAIR AND VFR WITH SFC WINDS LIGHT S AND CLIMB WINDS SE- SW
10-20KTS...VEERING TO NW FLOW BY 12KFT. THERE MAYBE A SITE OR TWO
WITH DAYBREAK BR. EXPECTING ANOTHER ROUND OF DIURNAL HEATING
CONVECTION FOR FRI AFTN. W/ A TWIST AS A COLD FRONT EDGES INTO
PLAY FOR THE OVERNIGHT AND MUCH OF SAT. SCT/NUMEROUS STORMS
EXPECTED TO BECOME NOCTURNAL. GUSTY WINDS AND TURBULENCE NEAR
DOWNPOURS/TOWERS WITH BETTER WX BY SUN WITH WEAK FROPA. /24/
&&
.PREV DISCUSSION... /ISSUED 927 PM CDT THU JUN 25 2015/
DISCUSSION...
OUTFLOW BOUNDARY HAS PUSHED INTO NORTHEAST TEXAS LATE THIS EVENING
BUT CONVECTION HAS NOT BEEN ABLE TO SUSTAIN ITSELF THIS EVENING
LIKE THE PREVIOUS TWO EVENINGS. LATEST HRRR IN GOOD AGREEMENT WITH
THIS ASSESSMENT SO IT SHOULD BE SAFE TO REMOVE POPS FROM THE
FORECAST FOR THE REMAINDER OF THE EVENING. CONCERNING TEMPS...
HAVE LOWERED TEMPS A FEW DEGREES ACROSS N LA WHERE EARLIER
RAINFALL ALREADY HAD 02Z TEMPS NEAR OR AT FCST MIN TEMPS. DID
RAISE TEMPS A DEGREE OR TWO ACROSS NE TX WHERE THE RAINFALL DID
NOT MAKE IT...FOLLOWING PERSISTENCE OVER THE LAST SEVERAL MORNINGS
IN THIS LOCATION. WE ARE LEFT WITH AN EXPANSIVE CLOUD DEBRIS
PATTERN ON IR IMAGERY IN THE WAKE OF THE CONVECTION SO BEEFED UP
SKY CONDITIONS FOR THE NEXT 6 HOURS OR SO BUT THE CLOUD COVER
SHOULD BEGIN TO THIN AFTER MIDNIGHT.
OTHER DEWPOINT/WIND GRIDS CHANGES WERE MOSTLY COSMETIC. UPDATE OUT
SHORTLY...13.
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 75 85 70 89 / 60 60 30 0
MLU 75 86 70 88 / 60 60 30 20
DEQ 70 86 66 87 / 60 30 10 0
TXK 72 86 68 88 / 60 40 10 0
ELD 73 84 68 88 / 60 50 20 0
TYR 75 88 70 89 / 50 50 20 0
GGG 75 86 70 88 / 50 50 20 0
LFK 75 89 71 90 / 40 60 40 30
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
24/14
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
326 AM CDT Fri Jun 26 2015
.SHORT TERM: (Tonight through Friday)
Issued at 322 AM CDT Fri Jun 26 2015
Active elements of large MCS over western MO will continue to move
south and southeast early this morning while the stratiform rain
area will continue to move east. RAP and HRRR continue to support
the solution that stratiform rain area with moderate to occasionally
heavy rain will slowly move east across the CWA today. RAP as well
as the GFS/NAM show strong 850-925 moisture convergence moving from
west to east across the area with PWATS near 2 inches. Will
maintain going flash flood watch given these parameters and the
saturated soils. Both the GFS and NAM show low level moisture
convergence shifting southeast of the CWA by 00Z with the upper
trough shifting east of the CWA by 06Z. Think that that the current
end time of the flash flood watch of 00Z still is okay because the
heavy rain should have ended by then. Rain chances overnight should
be just scattered showers over the southeast half of the CWA after
midnight.
Temperatures will be much cooler today behind the front with cloudy
skies, cold air advection, and rain. Highs in most areas will only
be in the 70s.
Britt
.LONG TERM: (Tonight through Thursday)
Issued at 322 AM CDT Fri Jun 26 2015
(Saturday and Sunday)
Dry weather is expect on Saturday as subsidence sets in behind the
exiting trough. Then chances of showers and thunderstorms increases
Sunday and Sunday night as a shortwave trough dives down embedded in
the northwestly flow aloft. MUCAPES will be in the 1500-2000 J/kg
range and deep layer shear will be in the 30-40kt range which may be
sufficient to produce a few isolated severe storms.
(Monday through Thursday)
Amplified upper pattern will dominate next week with shortwave
troughs moving through the area every other day. This will keep a
chance of showers and thunderstorm in the forecast during the period
with below normal temperatures.
Britt
&&
.AVIATION: (For the 00z TAFs through 00z Friday Evening)
Issued at 640 PM CDT Thu Jun 25 2015
Complex of showers and thunderstorms will affect the metro TAF
sites over the next few hours with heavy rain accompanied by IFR
visbilities possible along with gusty northwest winds. KUIN is
likely to stay just north of most activity while KCOU will also
likely have a period of storms this evening. Still anticipating
some break late this evening/early overnight period before an
organized bout of showers/storms associated with an MCS moves
roughly along I-70. MVFR ceilings and even visibilities are likely
behind this system into Friday afternoon along with a wind shift
to the northwest.
Specifics for KSTL:
Complex of showers and thunderstorms will affect the metro TAF
sites over the next few hours with heavy rain accompanied by IFR
visbilities possible along with gusty northwest winds. Still
anticipating some break late this evening/early overnight period
before an organized bout of showers/storms associated with an MCS
moves roughly along I-70 and affect KSTL Friday morning. Lingering
showers with embedded thunder likely into early Friday afternoon.
MVFR ceilings and even visibilities are also likely behind this
system into Friday afternoon along with a wind shift to the
northwest.
Gosselin
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...FLASH FLOOD WATCH through this evening FOR Audrain MO-Boone MO-
Callaway MO-Cole MO-Franklin MO-Gasconade MO-Jefferson MO-
Knox MO-Lewis MO-Lincoln MO-Marion MO-Moniteau MO-Monroe MO-
Montgomery MO-Osage MO-Pike MO-Ralls MO-Shelby MO-St.
Charles MO-St. Louis City MO-St. Louis MO-Ste. Genevieve MO-
Warren MO.
IL...FLASH FLOOD WATCH through this evening FOR Adams IL-Bond IL-
Brown IL-Calhoun IL-Clinton IL-Fayette IL-Greene IL-Jersey
IL-Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL-
Pike IL-Randolph IL-St. Clair IL-Washington IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
337 AM CDT FRI JUN 26 2015
.SYNOPSIS...
ISSUED AT 336 AM CDT FRI JUN 26 2015
AT 08Z...ISOLATED SHOWERS CONTINUE TO TRAIL TO THE WEST ACROSS
NCTRL NEBR BUT HAVE SHOWN RECENT TRENDS OF SLOWLY DISSIPATING AS
THEY DROP SOUTHWARD. MOST OF THE THUNDERSTORM ACTIVITY RESIDES
ACROSS PARTS OF KS AND MO. UPSTREAM ACROSS THE WRN DAKOTAS...MT
AND WYOMING SKIES ARE CLEAR IN MOST AREAS. TEMPERATURES IN WRN
NEBR RANGE FROM 59 TO 64 DEGREES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 336 AM CDT FRI JUN 26 2015
TODAY...THE H5 UPPER TROUGH AXIS AND ASSOCIATED VORT MAX AT 12Z
TO BE LOCATED IN WRN IA. UPSTREAM...THERE WILL BE CHANNELIZED
VORTICITY TODAY. WHILE THIS WOULD SEEM SUPPORTIVE OF AT LEAST
ISOLATED SHOWERS ACROSS THE ERN HALF OF FA AS INDICATED BY THE
HRRR AND RAP MODELS...LATEST NAM AND GFS ARE DRIER. A CROSS
SECTION ACROSS EASTERN AREAS SHOWS SUFFICIENT MOISTURE AVBL
EXCEPT THAT GENERAL SUBSIDENCE NOTED. CURRENT FCST IS DRY
TODAY...ALTHOUGH ISOLATED SHOWERS WOULD BE POSSIBLE. CURRENT BAND
OF SHOWERS EAST-WEST ACROSS CHERRY COUNTY TO HOLT COUNTY
CONTINUES TO DIMINISH IN COVERAGE AND EXPECTED TO DISSIPATED BY
12Z. THERE IS HOWEVER INCREASING COVERAGE OF STRATUS ACROSS THE
CENTRAL SANDHILLS INCLUDING THEDFORD ATTM. SATELLITE TRENDS SHOWS
AREA IS DEVELOPING TO THE SOUTHWEST WITH MAINLY MID LEVEL CLOUDS
COVERING NCTRL NEBR. ANY STRATUS SHOULD BEGIN TO SCATTER OUT
AFTER 15Z WITH SCT TO BKN STRATOCUMULUS EXPECTED TODAY. HIGHS
TODAY NEAR PREVIOUS FCST FROM 77 TO 81 DEGREES. WINDS STEADY
NORTH TO NORTHEAST 5 TO 10 MPH.
LOOKING SYNOPTICALLY ACROSS THE CONUS...THE UPPER RIDGE WILL
INTENSIFY ACROSS THE WRN CONUS AS THE UPPER TROUGH AMPLIFIES FROM
THE GREAT LAKES INTO THE MID MISSISSIPPI VALLEY. WEAK SURFACE
HIGH PRESSURE WILL BUILD SOUTH FROM THE NRN INTO THE CNTRL
PLAINS.
TONIGHT...UPPER FLOW WILL REMAIN NWRLY AS SURFACE HIGH PRESSURE
RESIDES OVER THE CENTRAL PLAINS. SKIES EXPECTED TO BE MOSTLY
CLEAR AND TEMPERATURES WILL BE COOLER FROM 55 TO 59 DEGREES.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 336 AM CDT FRI JUN 26 2015
THIS WEEKEND INTO THE FIRST OF NEXT WEEK WILL SEE A RIDGE
DOMINATE THE WESTERN CONUS AS A TROUGH DIGS OVER THE GREAT LAKES
REGION. NORTHWEST FLOW ACROSS THE HIGH PLAINS...HOWEVER THE RIDGE
RIDING SHORT WAVES/STORMS ARE EXPECTED TO REMAIN TO THE NORTHEAST
OF THE CWA. TEMPS ABOVE NORMAL /MORE SUMMER LIKE/ WITH HIGHS IN
THE MID 80S TO LOWER 90S.
MONDAY NIGHT INTO TUESDAY A STRONG DISTURBANCE WILL RIDE THE
CREST OF THE RIDGE AND CAUSE A SFC LOW PRESSURE TO DEVELOP ON THE
LEE SIDE OF THE ROCKIES. BY TUESDAY NIGHT THE LOW PRESSURE ALONG
WITH A TRAILING WEAK COLD FRONT WILL SLIDE SOUTH ACROSS THE
CENTRAL/HIGH PLAINS. MODELS STILL DIFFERING ON THE STRENGTH OF
LOW PRESSURE AND HOW STRONG THE CAP WILL BE. THUS STORMS ARE
POSSIBLE BUT THERE IS GREAT UNCERTAINTY. THE LATEST GFS HAS GONE
DRIER WHILE THE ECMWF HAS INCREASED QPF ACROSS THE AREA. ONE
AGREEMENT IS A SLIGHT BOOST OF TEMPS FOR TUESDAY AHEAD OF THE
FRONT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1135 PM CDT THU JUN 25 2015
THE PROBABILITY OF THUNDERSTORMS WILL DECREASE THE REST OF
TONIGHT. IN NORTHERN NEBRASKA...NORTH OF A BBW-TIF-MHN
LINE...ANOTHER THUNDERSTORM SYSTEM WILL MOVE THROUGH. AFTER THE
STORMS PASS...LOWER CEILINGS ARE LIKELY AS STRATUS FORMS IN THE
MOIST STABLE AIR LEFT IN THE WAKE OF THE STORMS. THOUGH THERE IS
A POSSIBILITY THAT CEILINGS BELOW 1000 FEET AGL WOULD FORM...THE
MORE LIKELY SCENARIO IS CEILINGS WILL BE 1000-2000 FEET. THE
NORTHERN STATIONS...NAMELY VTN...ANW AND ONL...HAVE A BETTER
CHANCE OF HAVING CEILINGS AT OR BELOW 1000 FEET THAN ARE THE
CENTRAL AND SOUTHWEST STATIONS...NAMELY BBW...LBF...OGA AND IML.
&&
.HYDROLOGY...
ISSUED AT 336 AM CDT FRI JUN 26 2015
CURRENT FLOOD WARNINGS FOR BRADY ON THE PLATTE RIVER SYSTEM AND
LEWELLEN ON THE NORTH PLATTE RIVER SYSTEM REMAIN IN PLACE. RIVER
LEVELS CONTINUE TO SLOWLY FALL. THE SOUTH PLATTE RIVER AT ROSCOE
IS CURRENTLY JUST BELOW FLOOD STAGE AT 8.9 FEET AND WILL CONTINUE
TO SLOWLY FALL THROUGH EARLY NEXT WEEK WITH THE FLOOD ADVISORY TO
CONTINUE. THE SOUTH PLATTE RIVER AT NORTH PLATTE IS CURRENTLY
NEAR 12.35 FEET AND WILL ALSO SLOWLY FALL THROUGH EARLY NEXT WEEK
WITH THE FLOOD ADVISORY TO CONTINUE. RECENT RAINFALL FROM LAST
EVENING DOES NOT APPEAR TO CAUSE CONCERN FOR ANY RISES...ONLY A
SLIGHTLY LESS FALL IN STAGE IN THE NEAR TERM. RIVER LEVELS ALONG
THE NORTH PLATTE RIVER UPSTREAM OF LAKE MCCONAUGHY ARE ELEVATED
NEAR ACTION STAGE AT LISCO WHILE REMAINING ABOVE MINOR FLOOD
STAGE AT LEWELLEN THROUGH EARLY NEXT WEEK.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...ROBERG
SHORT TERM...ROBERG
LONG TERM...MASEK
AVIATION...SPRINGER
HYDROLOGY...ROBERG
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
333 AM CDT FRI JUN 26 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 333 AM CDT FRI JUN 26 2015
THE CHANCE FOR THUNDERSTORMS TODAY IS THE PRIMARY FORECAST CONCERN.
THEN A GENERALLY DRY AND WARMER WEEKEND...WITH THE EXCEPTION OF A
SMALL CHANCE FOR STORMS SUNDAY.
NORTHWEST MID LEVEL FLOW ACROSS THE PLAINS WAS NOTED ON EVENING
UPPER AIR CHARTS AND SHORT TERM MODEL OUTPUT. A COUPLE OF SHORTWAVES
COULD BE IDENTIFIED WITHIN THE FLOW...AND RECENT RAP HEIGHT
FORECASTS ALONG WITH WATER VAPOR IMAGERY SUGGESTED ONE WAVE WAS
MOVING OUT OF SOUTHEAST NEBRASKA AS OF 3 AM...AND ANOTHER WAS
APPROACHING NORTHEAST NEBRASKA FROM SOUTH DAKOTA. BOTH WAVES WERE
TRIGGERING SCATTERED SHOWERS AND STORMS...HOWEVER THE STRONGEST WERE
IN NORTHERN KANSAS WHERE LIFT WAS MAXIMIZED JUST NORTH OF FRONTAL
BOUNDARY EXTENDING FROM KANSAS CITY TO WICHITA.
GIVEN NORTHWEST FLOW ALOFT...SOUTHERN STORMS MOVING OUT OF OUR AREA
WILL REMAIN THERE THIS MORNING. SHORTWAVE TO THE NORTH WILL
GRADUALLY WORK SOUTHEAST TODAY...BUT ABSENCE OF SURFACE BOUNDARY/LOW
LEVEL CONVERGENCE SUGGESTS ACTIVITY WILL REMAIN ISOLATED TO
SCATTERED IN NATURE. IN FACT...MANY SHORT RANGE MESOSCALE MODELS
INCLUDING HRRR AND RAP SUGGEST A DECREASE IN ACTIVITY THROUGH THE
MORNING BEFORE AFTERNOON HEATING HELPS BUBBLE UP WIDELY SCATTERED
AFTERNOON CONVECTION. SO WILL PLAY THE HIGHEST POPS IN NORTHEAST
NEBRASKA THIS MORNING...THEN BROADBRUSH SMALL CHANCES THROUGH THE
AFTERNOON ACROSS MUCH OF EASTERN NEBRASKA AND SOUTHWEST IOWA. COULD
SEE SOME LINGERING SHOWERS/STORMS IN SOUTHEAST NEBRASKA OR SOUTHWEST
IOWA DURING THE EARLY EVENING BEFORE SHORTWAVE PUSHES FARTHER AWAY
AND WE LOSE AFTERNOON HEATING.
OTHERWISE WE WILL SEE A TENDENCY TOWARD NORTHERLY LOW LEVEL FLOW
TONIGHT AND SATURDAY AS HIGH PRESSURE SETTLES ACROSS THE
REGION...AND BRINGS SLIGHTLY DRIER AIR INTO OUR AREA. SHOULD SEE
PLENTY OF SUNSHINE SATURDAY WITH HIGHS IN THE LOWER 80S AFTER
MORNING LOWS IN THE LOWER 60S.
SOUTHERLY FLOW WILL RETURN SATURDAY NIGHT AS A SHORTWAVE DIVES INTO
MINNESOTA THEN EVENTUALLY IOWA/WISCONSIN/ILLINOIS. SURFACE COLD
FRONT WILL FOLLOW THIS WAVE AND SWEEP THROUGH EASTERN NEBRASKA AND
SOUTHWEST IOWA ON SUNDAY. CONVECTION SATURDAY NIGHT SHOULD BE
CONFINED TO AREAS TO OUR NORTHEAST WHERE STRONG WARM ADVECTION IS
REALIZED JUST AHEAD OF MID LEVEL WAVE. ON SUNDAY...AXIS OF BEST LIFT
NEAR SHORTWAVE AND SURFACE REFLECTION WILL STILL LIE WELL TO OUR
EAST AND NORTHEAST IN MINNESOTA AND IOWA...BUT COULD SEE A FEW
SHOWERS OR STORMS NEAR AND EAST OF THE NEBRASKA/IOWA BORDER AS COLD
FRONT SWINGS SOUTHEAST. SHOULD SEE NICE WARMING ON SUNDAY AS
SOUTHWEST FLOW AHEAD AND NORTHWEST FLOW BEHIND FRONT WILL PROMOTE
DECENT MIXING. HIGHS THEN SHOULD EASILY REACH THE MID AND UPPER
80S.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 333 AM CDT FRI JUN 26 2015
GENERAL MID LEVEL FLOW PATTERN CHANGES ONLY A LITTLE DURING THE
WEEK. BROAD HIGH PRESSURE WILL REMAIN OVER THE SOUTHWESTERN STATES
THROUGH THE PERIOD. MEANWHILE UPPER LOW IN THE EASTERN GREAT LAKES
EARLY IN THE PERIOD WILL LIFT TO THE NORTHEAST...LEAVING BROAD
TROUGH BEHIND OVER THE EASTERN HALF OF THE COUNTRY. IN BETWEEN THESE
FEATURES...FLOW IN THE CENTRAL PLAINS WILL SHIFT FROM NEARLY
NORTHERLY TO NORTHWESTERLY BY MID WEEK. SEVERAL IMPULSES RIDING OVER
WESTERN RIDGE WILL ENTER THE PLAINS...BRINGING OFF AND ON
THUNDERSTORM CHANCES TO OUR REGION. GFS AND ECMWF ARE IN FAIRLY GOOD
AGREEMENT WITH THIS OVERALL PATTERN CHANGE...BUT DIFFER ON TIMING OF
PRECIPITATION-PRODUCING SHORTWAVES.
HOWEVER BOTH MODELS ARE RELATIVELY SIMILAR IN DROPPING A MORE
SIGNIFICANT SHORTWAVE INTO THE PLAINS ON TUESDAY...INCREASING
THUNDERSTORM CHANCES IN EASTERN NEBRASKA AND WESTERN IOWA TUESDAY
NIGHT AS ATTENDANT SURFACE LOW AND FRONTAL SYSTEM MOVE THROUGH THE
REGION. WILL HAVE THE HIGHEST PRECIP CHANCES AT THIS TIME...THOUGH
STILL ONLY IN THE CHANCE CATEGORY AS MOISTURE RETURN AFTER SUNDAY
COLD FRONT WILL BE SLOW TO OCCUR. SHOULD SEE MINIMAL RAIN CHANCES
BEHIND THIS SYSTEM ON WEDNESDAY AND THURSDAY...BUT GIVEN UNCERTAINTY
IN SMALL-SCALE MID LEVEL FEATURES...CAN NOT RULE OUT A STRAY STORM
OR TWO. OTHERWISE EXPECT TEMPERATURES TO AVERAGE 60S AND 80S FOR
LOWS AND HIGHS THROUGH THE PERIOD.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1200 AM CDT FRI JUN 26 2015
SHORTWAVE STILL MOVING THROUGH TONIGHT AND FRIDAY WILL RESULT IN
SPOTTY SHOWERS AND A FEW THUNDERSTORMS. MAINLY HAVE VFR CIGS WITH
SOME PERIODS OF SHOWERS THROUGH 18Z. DUE TO THE SPOTTY NATURE OF
THE THUNDERSTORM WILL HAVE TO MONITOR AND ADD IF NEEDED FOR THE
THUNDER THREAT. SOME PATCHY MVFR VSBYS MAY TRY TO DEVELOP BY
MORNING.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...DERGAN
LONG TERM...DERGAN
AVIATION...ZAPOTOCNY
AREA FORECAST DISCUSSION
NWS ELKO NV
230 AM PDT FRI JUN 26 2015
.SYNOPSIS...HIGH PRESSURE WILL BUILD OVER THE BATTLE BORN STATE
RESULTING IN TRIPLE DIGIT TEMPERATURES. EXPECT THE HEAT WAVE TO
PERSIST THROUGH MONDAY.
&&
.SHORT TERM...TODAY THROUGH SATURDAY. LOTS OF RIDGING THIS
FORECAST PERIOD...MEANWHILE THE HRRR AND GFS ARE DRY AS A
BONE...WITH THE RMOP IN UBER CONFIDENT TERRITORY. THE MEAN MAX
TEMP FOR THE ELKO AIRPORT ON JUNE 26TH IS 85F...AND IS 87F FOR
WINNEMUCCA... WENT FOR A HIGH OF 99F AND 101F RESPECTIVELY. FOR
JUNE 27TH THE MEAN MAX TEMP FOR THE ELKO AIRPORT IS 85F...AND IS
88F FOR WINNEMUCCA... WENT FOR A HIGH OF 101F AND 104F
RESPECTIVELY. ALL EYES WILL BE ON THE ASOS TO SEE IF THE RECORD
MAXIMUM TEMPERATURES GET SHATTERED.
.LONG TERM...SATURDAY NIGHT THROUGH NEXT FRIDAY. HUGE RIDGE IN PLACE
THROUGH THE PERIOD MAKES IT LOOK LIKE THE DOGS DAYS WHEN IT`S BARELY
THE END OF SPRING. HIGH TEMPS IN THE TRIPLE DIGITS OR NEAR THEM FOR
EVERYWHERE. SOME PLACES WILL CERTAINLY SET DAILY RECORD HIGHS...SOME
JUNE RECORDS. HOT ENOUGH TO PRODUCE LIMITED INSTABILITY...DRY
ENOUGH THAT INITIALLY CB BASES WILL BE ABOVE 12000 FEET...SOME CLOSE
TO 18000 FEET...FOR DRY THUNDERSTORMS. LATER A LOW FORMS
OFFSHORE...FUNNELING MOISTURE INTO THE GREAT BASIN...BUT IT`S
PATHETIC IN THE LOWER ATMOSPHERE AND...ALTHOUGH POPS RISE A FEW
POINTS...QPF IS STILL BASEMENT BARGAIN. TOWARD THE END OF THE LONG
TERM THE MODELS START TO QUARREL OVER HEIGHTS AND ORIENTATION...SO
NO TWEAKS THEN...JUST STATUS QUO. BB
&&
.AVIATION...VFR CONDITIONS ARE EXPECTED AT ALL TAF TERMINALS FOR THE
ENSUING 24 HR PERIOD. ISOLATED DRY THUNDER POSSIBLE AT KTPH AND KELY
FRIDAY AFTERNOON.
NOTE: LIGHTNING SENSOR AT KWMC HAS BEEN TEMPORARILY TURNED OFF TO
ELIMINATE FALSE REPORTS OF VCTS. REPAIRS WILL EFFECTED WHEN
POSSIBLE.
&&
.FIRE WEATHER...HOT AND DRY...HAINES OF 6 IMMINENT. WITH THE
RIDGE IN PLACE EXPECTING A MAJOR HEAT WAVE. SOME MOISTURE WILL BE
ABLE TO WORK ITS WAY AROUND THE BACK SIDE OF THE RIDGE SUPPORTING
ISOLATED DRY THUNDERSTORMS.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY FROM 11 AM THIS MORNING TO 8 PM PDT SUNDAY FOR
HUMBOLDT COUNTY-NORTHERN LANDER COUNTY AND NORTHERN EUREKA
COUNTY.
&&
$$
97/98/98
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1152 PM MDT THU JUN 25 2015
.AVIATION...
06Z TAF CYCLE
ISOLD THUNDERSTORMS WILL CONTINUE OVER SOUTH-CENTRAL NM OVERNIGHT...WITH
SCATTERED ACTIVITY NEAR KCVS CONTINUING UNTIL AROUND 07Z. ANOTHER
ROUND OF AFTERNOON AND EVENING CONVECTION EXPECTED FRIDAY BUT
STORMS WILL BE MARKEDLY STRONGER DUE TO A STRONG BACKDOOR COLD
FRONT DROPPING INTO ERN PLAINS DURING THE AFTERNOON AND THROUGH
CENTRAL NM DURING THE AFTERNOON. STORM MOTION WILL BE TOWARD THE
WEST OR SOUTHWEST AROUND 5KT. STRONG EAST CANYON WINDS LIKELY AT
KABQ BY LATE AFTERNOON WITH MODERATE TO STRONG SE WINDS AT KSAF.
SHOWERS AND STORMS WILL LINGER WELL AFTER SUNSET FRIDAY AS LARGE
SCALE ATMOSPHERIC LIFT KEEPS STORMS GOING.
33
&&
.PREV DISCUSSION...317 PM MDT THU JUN 25 2015...
.SYNOPSIS...
AN ACTIVE PERIOD OF WEATHER WILL BE THE RULE THROUGH AT LEAST
MONDAY. STORMS SHOULD EXPAND IN COVERAGE TONIGHT ACROSS THE
EASTERN PLAINS...PERHAPS RESULTING IN AN EAST CANYON WIND IN THE
RIO GRANDE VALLEY. STORM COVERAGE WILL INCREASE FURTHER ON FRIDAY
THANKS TO A BACK DOOR COLD FRONT PUSHING THROUGH THE GAPS OF THE
CENTRAL MOUNTAIN CHAIN. MOISTURE BEHIND THE FRONT WILL FUEL
THUNDERSTORMS THROUGH THE WEEKEND INTO MONDAY. SLOW STORM MOTIONS
AND HEAVY RAIN MAY LEAD TO FLASH FLOODING...ESPECIALLY ACROSS
VULNERABLE DRAINAGES. A DOWNTREND IN STORM COVERAGE IS POSSIBLE
TUESDAY AND WEDNESDAY...BUT STORM ACTIVITY WILL QUICKLY RAMP BACK
UP AGAIN ON THURSDAY THANKS TO ANOTHER BACK DOOR FRONT AND
MOISTURE SURGE.
&&
.DISCUSSION...
AS EXPECTED...ANOTHER CROP OF SHOWERS AND THUNDERSTORMS HAVE
DEVELOPED ACROSS THE HIGHER TERRAIN. AS THE UPPER HIGH REBUILDS
OVER THE FOUR CORNERS...STEERING FLOW WILL CONTINUE TO TAKE STORMS
TOWARD THE SOUTH. THUS FAR...STORMS HAVE BEEN MOVING JUST
ENOUGH...AND HAVE BEEN PULSEY ENOUGH...TO NOT CAUSE TOO MANY WATER
ISSUES.
HI-RES MODELS SHOWING STORMS FIRING ALONG A BOUNDARY NEAR THE E
NM/E CO BORDER THROUGH THE REMAINDER OF THE AFTN. APPEARS THAT
STORMS MAY GET SOMEWHAT ORGANIZED INTO A CLUSTER...FORMING A COLD
POOL...WITH STORMS PROPAGATING SOUTHWARD ACROSS THE PLAINS ALONG
THE OUTFLOW BOUNDARY. THE QUESTION WILL BE HOW FAR SOUTH THE
STORMS CAN HOLD TOGETHER BEFORE THE OUTFLOW BOUNDARY OUTRACES THE
STORMS. HRRR KEEPS STORMS TOGETHER AS FAR SOUTH AS ROSWELL...BUT
THE NAM SHOWS PRECIP FALLING APART SHORT OF THERE.
NONETHELESS...HAVE INCREASED POPS ACROSS THE EASTERN PLAINS
TONIGHT. THE SMALL DISTURBANCE NOTED ON WV SATELLITE IMAGERY
NOSING INTO NE NM ATTM SHOULD AID IN STORM DEVELOPMENT AND
MAINTENANCE. DEPENDING ON IF STORMS FIRE ALONG THE EAST SLOPES OF
THE SANDIAS...AS THE HRRR SUGGESTS...COULD SEE A PRETTY
STRONG...BUT SHORT-LIVED...EAST WIND INTO THE RGV.
FRIDAY LOOKS TO BE MORE ACTIVE THAN TODAY...ESPECIALLY ACROSS THE
PLAINS. THOUGH THE REMNANT BOUNDARY FROM TONIGHTS CONVECTION
SHOULD BE SOMEWHERE ACROSS THE PLAINS TOMORROW...A BACK DOOR
FRONT...LIKELY CONVECTIVELY AIDED... WILL SLIDE DOWN THE PLAINS
EARLY FRIDAY. THUS...MULTIPLE ROUNDS OF STORMS WILL BE
POSSIBLE...INITIALLY WITH THE FRONT...AND THEN AGAIN LATER IN THE
DAY AFTER THE FRONT NUDGES UP TO THE CENTRAL MTN CHAIN...IGNITING
STORMS...AND THOSE STORMS SHOULD TRAVEL S OR SE-WARD OUT INTO THE
PLAINS ONCE AGAIN. MEANWHILE...THE FRONT WILL PUSH THROUGH THE
CENTRAL MOUNTAIN CHAIN BY EARLY-MID AFTN...SPILLING LOW LEVEL
MOISTURE WESTWARD. THUS...EXPECT ANOTHER ROUND OF STORMS ACROSS
WESTERN NM AS WELL...PERHAPS WITH BETTER COVERAGE THAN TODAY. EAST
CANYON WINDS SHOULD ONCE AGAIN BE PRETTY STRONG.
WITH ABUNDANT MOISTURE /PWATS LIKELY ABOVE 1 INCH AREAWIDE/...
NORTH TO SOUTH STEERING FLOW...AND LOW LEVEL S TO SELY FLOW
THROUGH THE WEEKEND...AN ACTIVE PERIOD MIGHT BE AN UNDERSTATEMENT.
STEERING FLOW WILL REMAIN WEAK...AND STORMS CONTAINING HEAVY RAIN
IS A CERTAINTY. THIS SPELLS A RECIPE FOR FLASH FLOOD
POTENTIAL...AND A FLASH FLOOD WATCH MAY BE NEEDED. MONDAY LOOKS TO
BE MORE OF THE SAME...THOUGH A WEAK BOUNDARY WILL ALSO NOSE INTO
NE NM AS WELL.
ON TUESDAY AND WEDNESDAY... DRIER AIR LOOKS TO CIRCLE AROUND THE
HIGH AND OVER NM. THOUGH THIS SHOULD LIMIT CONVECTIVE COVERAGE
OVER THE FRI-SUN PERIOD...THERE WILL STILL BE ENOUGH MOISTURE
AROUND FOR THE HIGH TERRAIN TO SEE SOME ACTION.
ACTIVITY RAMPS BACK UP ON THURSDAY THANKS TO ANOTHER BACK DOOR
FRONT REPLENISHING MOISTURE ACROSS THE STATE. CURRENT INDICATIONS
IS THAT THIS FRONT WILL ALSO PUSH THROUGH THE GAPS OF THE CENTRAL
MTN CHAIN...SETTING THE STAGE FOR NUMEROUS SHRA/TSRA THURS...AND
FRIDAY. ANOTHER FRONT...OR PERHAPS OUTFLOW BOUNDARY FROM
CONVECTION MAY ARRIVE ON THE 4TH OF JULY. LOOKS LIKE MOTHER NATURE
WILL PROVIDE HER OWN FIREWORKS AGAIN THIS YEAR.
34
&&
.FIRE WEATHER...
NO REAL BIG CHANGES. A MORE SIGNIFICANT PUSH OF
MOISTURE FROM NORTHEAST TO SOUTHWEST WILL OCCUR TONIGHT THROUGH
FRIDAY NIGHT VIA A BACK DOOR COLD FRONT. THIS SURGE WILL KICK OFF
A WET PHASE TO THE MONSOON PERIOD.
AS FAR AS THE REST OF TODAY...HIT AND MISS STORMS CONTAINING WETTING
RAIN WILL IMPACT MOST OF THE AREA THROUGH THIS EVENING. THE MAIN
FOCUS AREA FOR WETTING RAIN WILL BE FOUND ACROSS EASTERN/CENTRAL
AREAS. THUNDERSTORMS SHOULD BLEED INTO THE EARLY MORNING HOURS ON
FRIDAY. EXPECT GOOD TO EXCELLENT HUMIDITY RECOVERIES. GUSTY OUTFLOW
WIND WILL BE ASSOCIATED WITH SOME OF THE STORMS. THE LOWEST HUMIDITY
WILL BE FOUND ACROSS THE FAR NORTHWEST. STORMS WILL TEND TO MOVE
TOWARDS A SOUTHERLY DIRECTION AND GENERALLY BE SLOW MOVING.
AS THE UPPER RIDGE SHIFTS FURTHER NORTHWEST OF THE STATE ON FRIDAY.
THIS WILL ALLOW A VIGOROUS BACK DOOR COLD FRONT TO SWEEP UNDERNEATH
AND REENERGIZE MOISTURE SUPPLIES WITHIN THE PERIPHERY OF THE UPPER
HIGH. HUMIDITY VALUES WILL GO UP AND TEMPERATURES WILL LOWER. A
FOCUS FOR WIDESPREAD WETTING RAIN WILL BE FOUND ALONG THIS FRONTAL
PUSH. CENTRAL AND EASTERN AREAS SHOULD BE FAVORED FRIDAY/FRIDAY
NIGHT AND THEN SHIFT WESTWARD ON SATURDAY. WETTING THUNDERSTORM
COVERAGE SHOULD LOWER SLIGHTLY ON SUNDAY BUT STILL BE PRETTY
WIDESPREAD. HIGHER HUMIDITY AND COOLER TEMPERATURES WILL ALSO
PREVAIL DURING THIS PERIOD. OUTFLOW WIND GUSTS WILL BE AROUND BUT
NOT AS STRONG COMPARED TO A DRIER ATMOSPHERIC ENVIRONMENT.
RESIDUAL IMPACTS OF THE MOISTURE TRAPPED WITHIN THE UPPER HIGH WILL
CONTINUE EARLY NEXT WEEK. ANOTHER BACK DOOR COLD FRONT IS POSSIBLE
SUNDAY NIGHT. A GRADUAL DRYING TREND IS EXPECTED TUESDAY AND COULD
POSSIBLY TREND INTO WEDNESDAY. BY LATE WEEK ANOTHER BACK DOOR COLD
FRONT SHOULD REPLENISH THE MOISTURE LOST EARLIER IN THE WAY AND
INCREASE WETTING THUNDERSTORM COVERAGE.
OVERALL VENTILATION WILL BE THE LOWEST DURING THE WEEKEND DUE TO
REDUCED MIXING HEIGHTS...PLENTY OF CLOUD COVER AND LOWER TRANSPORT
WINDS.
50
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1157 PM CDT THU JUN 25 2015
.UPDATE...
ISSUED AT 1157 PM CDT THU JUN 25 2015
LATEST LOCAL RADAR SHOWS AREAL COVERAGE OF SHOWERS SOUTHWEST AND
FAR SOUTH CENTRAL DIMINISHING. A RENEWED AREA OF SHOWERS
DEVELOPING OVER WELLS COUNTY MAY CONTINUE FOR THE NEXT COUPLE OF
HOURS PER LATEST HRRR AS THIS AREA SLIDES SOUTH. HAVE MENTIONED
ISOLATED SHOWERS NORTHERN JAMES RIVER VALLEY. ONLY ADDITION OF
WEATHER TO THE OVERNIGHT PERIOD WAS PATCHY FOG WEST AND PORTIONS
OF CENTRAL NORTH DAKOTA PER HRRR MODEL. THIS SEEMS REASONABLE
GIVEN THE SHOWERS EARLIER TODAY AND TEMPERATURE/DEWPOINT SPREADS
CLOSING UP ON EACH OTHER. WILL LET THE FLASH FLOOD WARNING THAT
WAS ISSUED EARLIER THIS EVENING FOR SOUTHWESTERN WILLIAMS AND
NORTHWESTERN MCKENZIE COUNTIES TO EXPIRE AT 1215 AM CDT FRIDAY.
STATE RADIO TELLS US TRAFFIC WAS MOVING NORMALLY IN THIS AREA AND
THE WATER HAS RECEDED.
UPDATE
ISSUED AT 944 PM CDT THU JUN 25 2015
WILL CONTINUE THE TREND OF SHOWERS/THUNDERSTORM CHANCES DECREASING
AS WE APPROACH MIDNIGHT. DRY OVERNIGHT THROUGH FRIDAY
MORNING...FOLLOWED BY ANOTHER ROUND OF AFTERNOON AND EVENING
SHOWERS AND THUNDERSTORMS.
UPDATE ISSUED AT 710 PM CDT THU JUN 25 2015
ISOLATED STORMS CONTINUE TO MOVE SOUTHEAST THROUGH THE WESTERN AND
CENTRAL PARTS OF THE FORECAST AREA...GENERALLY ALONG AND WEST OF
THE MISSOURI RIVER. SOME WERE PRODUCING SMALL HAIL AND WINDS TO 45
MPH. MESOSCALE MODELS SHOW A DECREASE IN INSTABILITY OVER THE
NEXT FEW HOURS. WILL EXPECT A WEAKENING OF STORMS...AND FOR THEM
TO DISSIPATE BY 10 PM OR SO.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 400 PM CDT THU JUN 25 2015
THE FORECAST FOCUS TODAY IS ON THUNDERSTORMS.
THUNDERSTORMS HAVE GREATLY INCREASED IN COVERAGE OVER THE PAST
COUPLE HOURS...AND PRECIPITATION CHANCES HAVE ONCE AGAIN BEEN
INCREASED. THE SOUTHWEST REMAINS THE MOST LIKELY AREA FOR SUSTAINED
CONVECTION...BUT WATER VAPOR SATELLITE IMAGERY INDICATES A COMPLEX
TRAIN OF MID LEVEL SHORTWAVES PARADING TOWARD THE DAKOTAS.
SO...WHILE ANY ONE OF THESE WAVES HAS SUFFICIENT DYNAMICS TO RELEASE
THE CONVECTIVE INSTABILITY IN PLACE...COVERAGE SHOULD DIMINISH AS
DIURNAL DESTABILIZATION REDUCES THIS EVENING. THIS FORECAST IS
SUPPORTED BY THE 12 UTC HIRES ARW/NMM AND THE LAST SEVERAL RUNS OF
THE HRRR. FINALLY...THE HIRES AND GLOBAL MODEL SUITE IS DRY BETWEEN
MIDNIGHT AND SUNRISE...SO PRECIPITATION CHANCES HAVE BEEN REMOVED
FROM THE FORECAST.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 358 PM CDT THU JUN 25 2015
THE WAVE THAT BRINGS ISOLATED STORMS AGAIN FRIDAY MOVES OUT BY
DAYBREAK SATURDAY ENDING THE STORM CHANCES. SATURDAY AND
SUNDAY...EVEN MONDAY...WILL BE DRY...MOSTLY SUNNY...AND VERY WARM
WITH HIGHS IN THE 80S...TOUCHING 90 LIKELY ON SATURDAY ACROSS THE
SOUTH. WINDS THROUGH THE PERIOD WILL BE 15 MPH OR LESS...LIGHT FOR
NORTH DAKOTA STANDARDS.
STORM CHANCES RETURN FOR TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1157 PM CDT THU JUN 25 2015
MENTIONED VCFG AT KDIK/KISN/KBIS THROUGH 15Z FRIDAY. OTHERWISE VFR
CIGS/VSBYS NEXT 24HR. A VCTS WAS ADDED TO KMOT/KBIS/KJMS AFTER
22Z FRIDAY THROUGH 02Z SATURDAY. ANY SHOWER OR THUNDERSTORM THAT
DEVELOPS WILL BE ISOLATED.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...SCHECK
LONG TERM...JPM
AVIATION...KS
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
321 AM EDT FRI JUN 26 2015
.SHORT TERM (TODAY AND TONIGHT)...
CONVECTION OVER KY HAS NOT MADE MUCH SOUTHWARD PROGRESS IN THE
PAST FEW HOURS. WITH THE MIDLEVEL FLOW GENERALLY FROM THE
WEST...OUR SW VA COUNTIES WILL HAVE THE BEST CHANCES OF RAIN THIS
MORNING. THE HRRR HAS NOT BEEN HANDLING THE SITUATION VERY
WELL...AND IT IS PROBABLY TOO AGGRESSIVE TO BRING THE CONVECTION
SE. THE NAM IS REALLY UNDERDONE WITH THE ONGOING ACTIVITY...AS WELL
AS THE RAP. WILL HAVE CHANCE POPS JUST ACROSS THE NORTH THIS
MORNING. WITH DAYTIME HEATING...WILL BRING POPS SOUTHWARD IN THE
AFTERNOON. CAPE WILL BE ABUNDANT TODAY WITH MLCAPES IN THE NAM OVER
3000 J/KG...SO SEVERE STORMS (WIND/HAIL) WILL BE POSSIBLE. THE
THREAT OF STORMS WILL CONTINUE OVERNIGHT AS LOW PRESSURE TRACKS
EAST ACROSS THE OHIO VALLEY...STRENGTHENING THE LLJ AND PUSHING THE
SURFACE COLD FRONT IN TO MIDDLE TN. RAIN CHANCES WILL RISE AFTER
MIDNIGHT TO LIKELY AND CATEGORICAL AS FORCING INCREASES. FLOODING
WILL BE A THREAT AS WELL WITH HIGH PW VALUES AND TRAINING CELLS
EXPECTED IN THE UNIDIRECTIONAL FLOW ALOFT. MOST AREAS HAVE BEEN DRY
THE PAST FEW DAYS AND CAN ABSORB QUITE A BIT OF RAIN...SO WILL NOT
ISSUE A FLOOD WATCH AT THIS TIME.
.LONG TERM (TOMORROW THROUGH FRIDAY)...
TOMORROW MORNING STARTS WITH THE COLD FRONT KNOCKING ON THE DOOR
OF OUR AREA. FRONT WILL USHER IN TWO THINGS THAT WE`VE BEEN MISSING
OUT ON FOR MOST OF THE MONTH... RAIN AND BELOW NORMAL TEMPERATURES.
LOOKS LIKE THE TIMING OF THE FRONT WILL LIMIT THE CHANCES FOR
WIDESPREAD SEVERE WEATHER AS ENERGY WILL BE LIMITED BY COOLER
TEMPERATURES. HOWEVER... CAN`T RULE OUT THE CHANCE FOR A FEW STORMS
TO CONVERGE OR STRENGTHEN TO THE POINT OF SEVERE LEVELS. THEY WILL
BE AIDED BY AN 850MB JET OVER THE AREA OF AROUND 30 - 40 KNOTS.
CAN`T RULE OUT SEVERE SIZE HAIL, BUT THE BIGGEST THREAT WOULD BE
DAMAGING WIND GUSTS WITH THESE STORMS. HIGH TEMPERATURES ON
SATURDAY WILL BE ABOUT 10 DEGREES COOLER THAN THEY WILL BE ON
FRIDAY, WITH MUCH OF THE AREA EXPECTED TO ONLY GET INTO THE LOWER
80`S. LOOKS LIKELY THAT WE WILL NOT EXPERIENCE ANY HIGH
TEMPERATURES IN THE 90`S THROUGH THE REMAINDER OF THE FORECAST.
RAIN CHANCES LOOK GOOD FOR MOST PLACES, WITH THE BEST CHANCES IN
THE NORTH CLOSER TO THE LOW MOVING OFF INTO NEW ENGLAND.
WE THEN DRY OUT BEHIND THE FRONT AS IT PUSHES MOISTURE SOUTH INTO
THE GULF OF MEXICO. RAIN CHANCES THEN INCREASE AS A SERIES OF WEAKER
SYSTEMS MOVE THROUGH THE AREA. CURRENTLY HAVE CONTINUOUS RAIN
CHANCES STARTING MONDAY THROUGH THE END OF THE 7-DAY FORECAST.
UNFORTUNATELY MODEL DIFFERENCES BECOME LARGER AS THEY STRUGGLE WITH
WHERE THE SYSTEMS WILL TRACK AND HOW MUCH PRECIPITATION WILL OCCUR.
BUT THEY ALL DO AGREE THAT WE WILL SEE SEVERAL SYSTEMS MOVE THROUGH
THAT SHOULD CAUSE AN INCREASE IN RAIN CHANCES/CLOUD COVERAGE WHILE
SEEING CONTINUOUSLY COOLER TEMPERATURES.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 94 72 85 63 / 50 70 80 20
KNOXVILLE MCGHEE TYSON AIRPORT, TN 92 71 82 61 / 40 70 80 20
OAK RIDGE, TN 91 70 81 62 / 50 80 80 20
TRI CITIES AIRPORT, TN 88 70 80 56 / 50 80 80 30
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS/ABM
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1139 PM CDT THU JUN 25 2015
.DISCUSSION...
UPDATED FOR 06Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 948 PM CDT THU JUN 25 2015/
UPDATE...
A WARM AND MUGGY EVENING ACROSS THE MIDSOUTH...WITH FAIR WEATHER
PREVAILING NEAR THE CENTER OF OF A 592DM 500MB RIDGE. TO THE
NORTH... AN MCS WAS RIDING THE PERIPHERY OF THE RIDGE ALONG THE
I-70 CORRIDOR.
THE 01Z HRRR MODEL APPEARED A LITTLE TOO QUICK IN GENERATING AND
ACCELERATING A COLD POOL DIRECTLY SOUTH FROM THE CENTRAL MO MCS.
REGARDLESS...OUTFLOW FROM THE CURRENT ACTIVITY ENTERING SOUTH
CENTRAL MO WILL LIKELY ENTER NORTHEAST AR AND THE MO BOOTHEEL
DURING THE EARLY OVERNIGHT. IT/S UNKNOWN IF THIS OUTFLOW WILL
GENERATE NEW CONVECTION AT IT MOVES SOUTH UNDER THE MIDLEVEL
RIDGE. MUCH WILL DEPEND ON IF THE COLD POOL CAN ORGANIZE AND
ACCELERATE SOUTHWARD AT THE RATE THE HRRR SUGGESTS.
FOR THE LATE EVENING UPDATE...HAVE INTRODUCED SLIGHT CHANCE POPS
FROM NORTHEAST AR THROUGH NORTHWEST LATE TONIGHT.
PWB
&&
.PREV DISCUSSION... /ISSUED 624 PM CDT THU JUN 25 2015/
.DISCUSSION...
UPDATED FOR 00Z AVIATION DISCUSSION.
PREV DISCUSSION... /ISSUED 256 PM CDT THU JUN 25 2015/
DISCUSSION...
SKIES REMAIN MOSTLY SUNNY OVER MUCH OF THE FORECAST AREA THIS
AFTERNOON WITH TEMPERATURES IN THE LOW TO MID 90S. TEMPERATURES
ARE ACTUALLY RUNNING A COUPLE OF DEGREES COOLER THAN YESTERDAY AND
HEAT INDEX VALUE ARE ALSO NOT QUITE AS HIGH AS WELL. SOME LOCATIONS
ALREADY HAVE HAD HEAT INDEX READINGS ABOVE 105 AND WITH A COUPLE
MORE HOURS OF HEATING LEFT SOME OTHER AREAS MAY ALSO REACH ABOVE
105. WILL LET HEAT ADVISORY CONTINUE THROUGH 7 PM CDT. CURRENT
RADAR SHOWS VERY LITTLE IF ANY THUNDERSTORM ACTIVITY OVER THE
FORECAST AREA SO IT APPEARS THAT MOST AREAS SHOULD REMAIN DRY
TONIGHT.
CURRENTLY A NEARLY STATIONARY BOUNDARY EXTENDS ACROSS THE CENTRAL
PLAINS THROUGH THE OHIO VALLEY AND INTO THE MID-ATLANTIC STATES.
THIS FRONT WILL START TO MOVE SOUTH AS A COLD FRONT ON FRIDAY.
THUNDERSTORMS ARE EXPECTED TO DEVELOP AHEAD OF THE FRONT AND SOME
OF THESE THUNDERSTORMS SHOULD MOVE INTO THE FORECAST AREA. THERE
IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
NORTHEAST ARKANSAS...THE MISSOURI BOOTHEEL AND NORTHWEST TENNESSEE
WITH DAMAGING WINDS AND LARGE HAIL AS THE MAIN THREATS.
TEMPERATURES WILL BE A LITTLE COOLER WITH THE INCREASE IN CLOUDS
AHEAD OF THE FRONT AS HIGHS WILL BE MAINLY IN THE LOWER 90S. HEAT
INDEX VALUES WILL NOT BE AS HIGH AS THEY HAVE BEEN THE LAST COUPLE
OF DAYS SO A HEAT ADVISORY WILL NOT BE NEEDED.
THE COLD FRONT WILL CONTINUE TO MOVE SOUTH AND WILL REACH NORTHERN
SECTIONS OF THE FORECAST AREA FRIDAY NIGHT SO THERE WILL BE A
BETTER CHANCE OF THUNDERSTORMS. THE SLIGHT RISK OF SEVERE
THUNDERSTORMS WILL CONTINUE OVER NORTHERN SECTIONS OF THE FORECAST
AREA AS WELL. TEMPERATURES WILL NOT BE AS WARM AS THEY BEEN THE
LAST FEW DAYS WITH LOWS SATURDAY MORNING IN THE UPPER 60S TO LOWER
70S.
THE COLD FRONT WILL EXIT THE FORECAST AREA SATURDAY MORNING WITH
THUNDERSTORMS ENDING OVER NORTH MISSISSIPPI. MUCH COOLER AND DRIER
AIR WILL MOVE INTO THE REGION BEHIND THE FRONT WITH HIGHS ON
SATURDAY ONLY IN THE LOW TO MID 80S. HIGH PRESSURE WILL BUILD INTO
THE REGION SATURDAY NIGHT WITH LOWS SUNDAY MORNING MAINLY IN THE
60S. DRY WEATHER AND BELOW NORMAL TEMPERATURES WILL CONTINUE INTO
SUNDAY.
BY SUNDAY NIGHT...ANOTHER COLD FRONT WILL START TO MOVE INTO THE
CENTRAL PLAINS AND THE MID MISSISSIPPI VALLEY. SOME ISOLATED
THUNDERSTORMS MAY BE POSSIBLE OVER EXTREME NORTHWEST SECTIONS OF
THE FORECAST AREA. BY MONDAY...THE COLD FRONT WILL CONTINUE TO
MOVE SLOWLY SOUTH TOWARD THE FORECAST AREA. AS IT DOES THERE WILL
BE A LITTLE BETTER CHANCE OF THUNDERSTORMS. TEMPERATURES WILL
CONTINUE TO BE BELOW NORMAL WITH HIGHS IN THE MID 80S.
THE COLD FRONT WILL START TO STALL OUT ALONG THE NORTHERN BORDER
OF THE FORECAST AREA SO THERE WILL STILL BE SCATTERED THUNDERSTORMS
FOR TUESDAY THROUGH NEXT THURSDAY. TEMPERATURES WILL CONTINUE TO
BE BELOW NORMAL THROUGH THE PERIOD.
ARS
&&
.AVIATION...
06Z TAF CYCLE (26/06Z-27/06Z)
VFR MOST OF THE PERIOD UNTIL CONVECTION DEVELOPS ALONG A PASSING
COLD FRONT. NARROWED DOWN TIMING OF HEAVIER ACTIVITY...RESULTING
IN EXPECTED IMPACTS DURING FEDEX NIGHT OPS AT MEM. IT IS POSSIBLE
FOR ISOLATED EARLIER/AFTERNOON ACTIVITY AHEAD OF THE FRONT...BUT
CONFIDENCE FOR NOW IS LEANING TOWARDS A VCSH REMARK. REMAINED
CONSERVATIVE WITH STORM INDUCED WINDS...KNOWING THAT A FEW STORMS
IN THE AREA COULD PRODUCE STRONGER GUSTS. CONVECTION WILL START TO
IMPACT TUP AT THE VERY END OF THE PERIOD WHILE IT STARTS TAPERING
OFF AT JBR. LIGHT SOUTHWEST GRADIENT WINDS WILL INCREASE TO 8 TO
12 KTS BY MID MORNING...WITH AFTERNOON GUSTS AT JBR AND MEM.
JAB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS ALBANY NY
959 AM EDT FRI JUN 26 2015
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE REGION THIS
AFTERNOON WITH ISOLATED SHOWERS MAINLY FROM THE MOHAWK VALLEY
SOUTH AND EAST. THEREAFTER...HIGH PRESSURE WILL BUILD OVER THE
REGION LATE THIS AFTERNOON INTO THIS EVENING...RESULTING IN A
BRIEF PERIOD OF FAIR AND DRY WEATHER. AN INTENSIFYING STORM OVER
THE OHIO VALLEY WILL APPROACH ON SATURDAY...BRINGING PERIODS OF
RAIN AND COOL CONDITIONS FOR THIS FIRST FULL WEEKEND OF SUMMER.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 959 AM EDT...THIS UPDATE IS TO RETOOL THE POP TRENDS AND
CLOUD COVERAGE ACROSS THE REGION. THE COLD FRONT HAS SLIPPED SOUTH
OF THE REGION WITH THE MAIN FEATURE OF INTEREST THE UPPER LEVEL
TROUGH AXIS MOVING TOWARDS THE ST LAWRENCE RIVER VALLEY PER THE
LATEST HRRR/RAP40/NAM. PARTLY CLOUDY/MOSTLY CLEAR CONDITIONS WILL
BECOME MOSTLY CLOUDY FROM THE CAPITAL REGION/MOHAWK VALLEY SOUTH
WITH THE UPPER TROUGH PASSAGE THIS AFTERNOON. SOME ISOLD SHOWERS
ARE POSSIBLE DUE TO THE CYCLONIC VORTICITY ADVECTION DUE TO THE
SHORT-WAVE ROTATING AROUND THE UPPER LOW. SOME SCT SHOWERS ARE
POSSIBLE OVER THE HIGHER TERRAIN. ANY RAINFALL AMOUNTS SHOULD BE
LIGHT WITH A FEW HUNDREDTHS. THE LATEST HRRR INDICATES THE SHOWER
SHOULD DIMINISH NORTH OF THE CAPITAL REGION/MOHAWK VALLEY IN THE
EARLY PM.
HIGHS MOSTLY IN THE MID TO UPPER 70S FOR VALLEY LOCATIONS WITH
UPPER 60S TO LOWER 70S FOR THE HIGHER TERRAIN.
INTO TONIGHT...SURFACE HIGH BUILDS AND CRESTS ACROSS THE REGION
FOR A TRANQUIL PERIOD OF WEATHER. A LIGHT NORTHERLY WIND WILL
SUBSIDE TO LIGHT AND VARIABLE UNDER PTCLOUDY-MOCLEAR SKIES.
HOWEVER...THE METEOROLOGICAL EYES WILL BE WATCHING WHAT TRANSPIRES
UPSTREAM AS NCEP MODEL SUITE AND INTERNATIONAL GUIDANCE ARE
BECOMING MORE IN AGREEMENT WITH AN ANOMALOUS DIGGING/PHASING
TROUGH ACROSS THE MID WEST WITH EXPANDING AREA OF CLOUDS AND
RAIN/SHOWERS. CLOUD COVERAGE MAY APPROACHING OUR SOUTHERN MOST
ZONES OVERNIGHT BUT IT WILL REMAIN DRY. OVERNIGHT LOWS MAINLY INTO
THE 50S WITH SOME UPPER 40S ACROSS PORTIONS OF THE
DACKS...BERKS...SOUTHERN GREENS.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
IMPRESSIVE STORM TO DEVELOP ACROSS THE OHIO VALLEY AND IMPACT
OUR REGION THIS WEEKEND...
THE PREVIOUS EXCELLENT AFD FOLLOWS WITH MINOR UPDATES PER THE 00Z
GUIDANCE.
SATURDAY...THE 26/00Z ECMWF SHOWS THE SFC WAVE MOVING A LITTLE
SLOWER TOWARDS A MID LEVEL JET CONFLUENT REGION OVER E-OH AND W-PA
BY MID MORNING. THE ISENTROPIC LIFT INCREASES QUICKLY ON THE
290-300K SFC BY THE LATE MORNING INTO THE AFTERNOON ESPECIALLY
SOUTH AND WEST OF THE CAPITAL REGION. THE LOW-LEVEL BAROCLINIC
LEAFLET STRENGTHENS BETWEEN THE RETREATING AND STRENGTHENING HIGH
OFF THE NEW ENGLAND COAST /1022MB/ ...AND THE LOW PRESSURE SYSTEM
MOVING TOWARDS LAKE ERIE AND WRN PA BY THE EARLY PM WITH SUB
1000MB EXPECTED. THE GFS/ECMWF ATTEMPT TO HAVE A SECONDARY LOW
FORM OVER THE MID ATLANTIC REGION THROUGH THE AFTERNOON. OVER
RUNNING RAINFALL AHEAD OF THE PRIMARY SFC CYCLONE...AND THE WARM
FRONT SHOULD OVER SPREAD THE REGION BY THE EARLY EVENING. AN
ANOMALOUS H850/925 E/SE LLJ INCREASES AHEAD OF THE SFC WAVE TO
BETTER THAN 40KTS. THE LATEST GFS/ECMWF HAVE E/SE WINDS OF 45-55KTS
OVER THE FCST AREA BY 8 PM SAT. PLENTY OF ATLANTIC MOISTURE
ENTRAINMENT SHOULD BE ADVECTED INTO THE REGION FOR PERIODS OF
MDT-HVY RAIN BY SAT EVENING. HIGHS WILL BE BELOW NORMAL WITH MID
AND U60S COMMON IN THE LOWER ELEVATIONS AND M50S TO L60S OVER THE
HIGHER TERRAIN ACROSS THE CATSKILLS.
SATURDAY NIGHT...THIS WILL BE THE HIGHEST POTENTIAL IMPACT
PERIOD...AND WILL CONTINUE WHAT THE PREVIOUS SHIFT HIGHLIGHTED IN
THE SEGMENTED HWO. THE GEFS INDICATE ANOMALOUS LLJ WITH U-WIND
ANOMALIES 3 TO 5 STANDARD DEVIATIONS GREATER THAN NORMAL /STRONG
EASTERLIES/ AND STRONG V-WIND ANOMALIES /STRONG SOUTHERLIES/ 3 TO
5 STANDARD DEVIATIONS GREATER THAN NORMAL. HENCE...A SE LOW-LEVEL
JET MAX WILL FOCUS PERIODS OF MODERATE TO HEAVY RAINFALL. THE E/SE
FLOW WILL ENHANCE THE RAINFALL ALONG THE SPINE OF THE ERN
DACKS...ERN CATSKILLS...SRN GREENS..BERKS...AND NORTHERN LITCHFIELD
HILLS. PWATS LOOK TO BE 1 TO 2 STD DEVS ABOVE NORMAL...SLIGHTLY
HIGHER SOUTH AND EAST OF THE CAPITAL DISTRICT WHERE UP TO 3 STD IS
CURRENT PROGGED. THERE IS A SMALL WINDOW WHERE THE E/SE WINDS MAY
GUST CLOSE TO WIND ADVISORY LEVELS OVER THE SRN GREENS IN SRN
VT...NRN TACONICS...AND POSSIBLY THE NRN BERKS. IT WILL DEPEND ON
HOW MUCH MOMENTUM CAN BE TRANSFERRED TO SFC THROUGH A STRONG
INVERSION IN THE SOUNDINGS AND ITS OCCURRING NOCTURNALLY. WE WILL
MENTION THE THREAT AND CONTINUE WHAT THE DAY SHIFT HAS IN THE
HWO. IT IS HARD TO TELL HOW MUCH OF A THREAT THE RAIN WILL HAVE
FOR FLOODING AT THIS TIME. 1 TO 3 INCHES LOOKS POSSIBLE SAT PM
INTO SUNDAY MORNING BASED ON THE EC/WPC/CAN GGEM GUIDANCE...WITH
THE MESOSCALE MODELS SHOWING SOME 3-4 INCH AMOUNTS IN THE ERN
CATSKILLS...AND ERN DACKS. PER EXTENSIVE COLLABORATION FROM
SURROUNDING WFOS...CONFIDENCE REMAINS LOW FOR A FLOOD WATCH
AT THIS TIME...BUT WILL CONTINUE TO MONITOR AND MENTION IN THE
HWO. ZONE FFG VALUES REMAIN HIGH IN THE 3/6-HR TIME FRAME.
CATEGORICAL POPS WERE CONTINUED WITH RAIN...HVY AT
TIMES...SATURDAY NIGHT. IN ADDITION...SHOWALTER VALUES ARE PROGGED
EVEN LOWER WITH SUB ZERO VALUES ADVECTING INTO THE REGION TO
WARRANT AN INCLUSION OF THUNDERSTORMS OVERNIGHT. LOWS WILL BE
MAINLY IN THE 50S.
SUNDAY...MODEL TRENDS NOW WANT TO ADVECT IN A DRY SLOT DURING THE
DAY WHICH WILL REDUCE THE PRECIP COVERAGE AND INTENSITY ACROSS
MOST OF THE REGION FOR A SMALL WINDOW OF TIME. QUESTION IS IF WE
ARE ABLE TO SEE SOME INSOLATION TO ASSIST WITH DESTABILIZATION.
WHILE THE MAIN THRUST OF ADVECTION WILL BE WELL TO OUR NORTH...THE
VERTICALLY STACKED LOW ACROSS WESTERN NY WITH SECONDARY LOW
POSSIBLY TRACKING NORTH...NARROW LINES OF CONVECTION COULD EVOLVE.
WE WILL FOLLOW A BLENDED MOS VALUES WHICH REQUIRES A SLIGHT
ADJUSTMENT UPWARD IN THE AFTERNOON HIGH TEMPS TO LOWER HALF OF THE
70S FOR VALLEY LOCATIONS AND 60S ELSEWHERE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE LARGE VERTICALLY STACKED STORM SYSTEM IMPACTING THE REGION WILL
FINALLY START TO MOVE AWAY ON SUNDAY NIGHT...AS BOTH THE SFC AND
UPPER LEVEL LOWS MOVE FROM UPSTATE NY TOWARDS SOUTHERN QUEBEC AND
NORTHERN NEW ENGLAND. AS A RESULT...CHANCES FOR RAIN SHOWERS WILL
DECREASE THROUGH THE OVERNIGHT HOURS ON SUN NIGHT...ALTHOUGH WITH
CYCLONIC FLOW STILL IN PLACE...A FEW LIGHT RAIN SHOWERS AND PLENTY
OF CLOUDS REMAIN POSSIBLE. MIN TEMPS LOOK TO FALL INTO THE MID 50S
FOR MOST PLACES.
BY MONDAY...WEAK RIDGING ALOFT WILL POKE INTO THE REGION...ALLOWING
FOR PARTIAL SUNSHINE. CANNOT TOTALLY RULE OUT A BRIEF SHOWER...ESP
EARLY IN THE DAY...ACROSS THE ADIRONDACKS OR SRN GREENS...BUT MOST
AREAS LOOK TO STAY DRY. MAX TEMPS SHOULD REACH INTO THE MIDDLE TO
UPPER 70S FOR VALLEY AREAS...WITH 60S FOR THE HIGH TERRAIN. DRY
WEATHER LOOKS TO CONTINUE INTO MONDAY NIGHT WITH LOWS IN THE 50S
ONCE AGAIN.
WITHIN THE FLOW AT 500 HPA...ANOTHER SHORTWAVE TROUGH WILL ROTATE
TOWARDS THE REGION FROM THE GREAT LAKES. COMBINED WITH A MOIST
SOUTHERLY FLOW AND DAYTIME HEATING...A FEW ROUNDS OF SHOWERS AND
THUNDERSTORMS CAN BE EXPECTED FOR TUESDAY...ESP DURING THE AFTN AND
EVENING. CAN/T RULE OUT A FEW STRONG STORMS...ALTHOUGH WILL
ULTIMATELY DEPEND ON HOW MUCH INSTABILITY WILL BE IN PLACE. MAX
TEMPS LOOK TO REACH CLOSE TO 80 IN MANY VALLEY AREAS.
SHOWERS AND THUNDERSTORMS WILL WIND DOWN ON TUESDAY EVENING WITH THE
LOSS OF DAYTIME HEATING AND AS THE BEST UPPER LEVEL FORCING SHIFT
EASTWARD. HOWEVER...MORE SHOWERS AND THUNDERSTORMS ARE POSSIBLE ON
WEDNESDAY WITH THE BROAD UPPER LEVEL TROUGH REMAINING OVER THE AREA
AND ANOTHER SHORTWAVE ROTATING BY CLOSE TO THE REGION. TEMPS ONCE
AGAIN LOOK TO REACH THE UPPER 70S TO NEAR 80.
DRIER WEATHER LOOKS TO RETURN FOR THE LATE WEEK PERIOD...ALTHOUGH
THIS WILL BE DETERMINED BY JUST WHEN THE FLOW AT 500 HPA CAN FLATTEN
OUT. WILL CONTINUE SLIGHT TO LOW CHC POPS FOR THURSDAY DUE TO THE
UNCERTAINTY...WITH TEMPS MAINLY IN THE UPPER 70S.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS WILL CONTINUE FOR ALL TAF SITES FOR TODAY INTO
TONIGHT.
A WEAK UPPER LEVEL DISTURBANCE IS PASSING BY TO THE NORTH OF THE
REGION. THIS SYSTEM HAS ALLOWED FOR SOME VERY LIGHT RAIN SHOWERS
OVERNIGHT. MOST OF THESE SHOWERS ARE DEPARTING OFF TO THE
EAST...AND ASIDE FROM A BRIEF SHOWER/SPRINKLE OVER THE NEXT HOUR
OR TWO...NO ADDIIONAL RAIN IS EXPECTED AT THE TERMINALS TODAY. ANY
SHOWER EARLY THIS MORNING WILL BE VERY LIGHT AND HAVE LITTLE TO
NO EFFECT ON VSBYS/CIGS.
OTHERWISE...BKN MID LEVEL CLOUDS THIS MORNING WILL EVENTUALLY
BECOME SCT FOR THIS AFTN. NORTHERLY WINDS WILL PICK UP TO 5-10 KTS
FOR DURING THE DAY TODAY.
WINDS WILL DECREASE THIS EVENING WITH THE LOSS OF DAYTIME
HEATING/MIXING. HIGH CLOUDS WILL INCREASE THROUGH THE EVENING
HOURS...AND BECOME SCT-BKN FOR ALL SITES BY THE LATE EVENING
HOURS...AS A STORM SYSTEM STARTS TO APPROACH FROM THE OHIO VALLEY.
ANY RAIN LOOKS TO HOLD OFF UNTIL DURING THE DAY SATURDAY.
OUTLOOK...
SATURDAY THROUGH SUNDAY: HIGH OPERATIONAL IMPACT. RA LIKELY.
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
MONDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
&&
.FIRE WEATHER...
MINIMAL TO LOW FIRE WEATHER RELATED CONCERNS THROUGH THE WEEKEND
AS ISOLATED TO SCATTERED SHOWERS PERSIST INTO THIS MORNING. A
BRIEF PERIOD OF DRY WEATHER IS EXPECTED LATER THIS AFTERNOON INTO
EARLY SATURDAY MORNING BEFORE A WIDESPREAD...SOAKING RAINFALL
OCCURS FOR THE MAJORITY OF THE REGION SATURDAY AFTERNOON INTO
SUNDAY MORNING.
THE RH VALUES WILL LOWER TO 40 TO 60 PERCENT TODAY WITH THE LOWER
VALUES NORTH OF THE MOHAWK RIVER VALLEY. THE RH VALUES WILL HAVE
AN EXCELLENT RECOVERY SATURDAY MORNING IN THE 75 TO 100 PERCENT
RANGE AND REMAIN HIGH THROUGH THE DAY AS WET WEATHER SPREADS
ACROSS THE ENTIRE REGION.
THE WINDS WILL LIGHT FROM THE NORTH TO NORTHWEST AT AROUND 10 MPH
TODAY...BECOMING LIGHT AND VARIABLE TO CALM WINDS FRIDAY NIGHT.
&&
.HYDROLOGY...
LIGHT RAIN SHOWERS WILL IMPACT MANY PORTIONS OF THE FORECAST AREA
THROUGH THIS MORNING WITH RAINFALL AMOUNTS GENERALLY ONE TENTH OF
AN INCH OR LESS.
DRIER WEATHER IS EXPECTED LATE THIS AFTERNOON INTO SATURDAY
MORNING BEFORE A STRONG LOW PRESSURE SYSTEM DEVELOPS NEAR THE OHIO
VALLEY AND MOVES TOWARDS THE EASTERN GREAT LAKES REGION. PERIODS
OF MODERATE TO HEAVY RAINFALL ARE POSSIBLE LATE SATURDAY AFTERNOON
INTO SUNDAY...DEPENDING ON THE EVENTUAL TRACK AND EVOLUTION OF LOW
PRESSURE DEVELOPING ACROSS THE OHIO VALLEY REGION.
RIGHT NOW...ONE TO UP TO TWO INCHES OF RAINFALL ARE POSSIBLE
ACROSS THE HSA WITH UP TO 3 INCHES OR SO OVER THE EASTERN
CATSKILLS...AND POSSIBLE THE EASTERN ADIRONDACKS. THE TRACK AND
RAINFALL DURATION WILL DETERMINE WHERE THE HIGHER AMOUNTS WILL OCCUR.
THE LATEST MMEFS GUIDANCE CONTINUES TO SUGGEST WITHIN BANK RISES
TO THE CAUTION OR ALERT STAGES AT A FEW SITES AT THIS TIME.
URBAN AND SMALL STREAM CONCERNS ACROSS THE HSA WILL HAVE TO BE
MONITORED...AND WILL MENTION IN THE HWO. ALSO...IF CONFIDENCE
INCREASES FOR THE POTENTIAL OF WIDESPREAD MINOR FLOODING...THEN A
FLOOD WATCH MAY BE NEEDED FOR PORTIONS OF THE HSA LATER IN TIME.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR
WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...BGM/WASULA
NEAR TERM...BGM/WASULA
SHORT TERM...BGM/WASULA
LONG TERM...FRUGIS
AVIATION...FRUGIS
FIRE WEATHER...BGM/WASULA
HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
913 AM EDT FRI JUN 26 2015
.SYNOPSIS...
HOT TEMPERATURES WILL PREVAIL TODAY AS A COLD FRONT LINGERS TO OUR
NORTH. SOMEWHAT COOLER TEMPERATURES AND MORE WIDESPREAD
THUNDERSTORMS ARE LIKELY SATURDAY AS AN UPPER-LEVEL TROUGH
DEVELOPS OVER THE EASTERN STATES. A COLD FRONT WILL CROSS THE AREA
SATURDAY NIGHT WITH DRY CONDITIONS AND TEMPERATURES NEAR NORMAL
ARRIVING EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPPER-LEVEL RIDGING OVER THE FORECAST AREA WILL HELP SUPPORT
ANOTHER HOT DAY WITH HIGHS NEAR 100. SUPPORT FOR THUNDERSTORMS
WILL BE MAINLY CONVERGENCE INTO A HEAT TROUGH AND POSSIBLE OUTFLOW
BOUNDARIES FROM PREVIOUS CONVECTION...MAINLY IN THE NORTH PART.
SOMEWHAT SHALLOW MOISTURE ASSOCIATED WITH THE UPPER-RIDGING SHOULD
LIMIT COVERAGE. THE HRRR AND ARW DISPLAY ISOLATED TO SCATTERED
COVERAGE MAINLY AFTER 200 PM AND IN THE NORTH PART. THE SPC WRF HAS
THE GREATEST THUNDERSTORM COVERAGE AROUND 800 PM. A THREAT OF
THUNDERSTORMS WILL CONTINUE TONIGHT MAINLY BECAUSE OF OUTFLOW
BOUNDARY INTERACTION EARLY. THE MODELS ALSO INDICATE UPPER-LEVEL
LIFT LATE AHEAD OF A MID-LEVEL SHORTWAVE TROUGH. WE KEPT CHANCE
POPS THROUGH THE NIGHT.
STRONG INSTABILITY WITH CONSIDERABLE CAPE IN THE HAIL GROWTH AREA
INDICATES A THREAT OF DAMAGING WIND AND HAIL WITH ANY
THUNDERSTORMS THIS AFTERNOON INTO THE EVENING.
THE TEMPERATURE GUIDANCE WAS CLOSE TONIGHT WITH LOWS IN THE MID
AND UPPER 70S.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
AS THE UPPER TROUGH DEEPENS OVER THE EASTERN STATES...A SURFACE
LOW PRESSURE SYSTEM WILL CROSS THE UPPER MISSISSIPPI RIVER VALLEY
TO THE GREAT LAKES REGION. ITS ASSOCIATED COLD FRONT WILL CROSS
OUR AREA SATURDAY NIGHT. EXPECT WIDESPREAD CONVECTION SATURDAY AS
A COUPLE OF SHORT WAVES MOVE THROUGH AND INSTABILITY INCREASES. PW
VALUES WILL BE AROUND 2.O SO LOCALLY HEAVY RAINS WILL BE
ASSOCIATED WITH THUNDERSTORMS. KEPT HIGHS IN THE UPPER 80S AND
LOWER 90S ON SATURDAY...WHICH ARE A FEW DEGREES BELOW GUIDANCE
CONSENSUS...GIVEN CLOUDS AND PRECIP. LOWS SATURDAY NIGHT ARE
EXPECTED TO RANGE FROM THE MID 60S WEST TO LOWER 70S EAST AS
CONVECTION COMES TO AN END BEHIND THE COLD FRONT.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
GFS AND ECMWF IN GOOD AGREEMENT KEEPING THE UPPER LEVEL TROUGH
ACROSS THE EASTERN STATES SUNDAY THEN SHIFTING OFF THE COAST BY
THE MIDDLE OF NEXT WEEK. SURFACE HIGH PRESSURE WILL USHER IN DRIER
MORE STABLE AIR BEGINNING SUNDAY AND CONTINUING THROUGH MONDAY.
MOISTURE AND INSTABILITY BEGIN TO INCREASE AGAIN TUESDAY AND
WEDNESDAY.
HIGHS IN THE UPPER 80S SUNDAY...AROUND 90 MONDAY...AND 90 TO 95
TUESDAY AND WEDNESDAY.
&&
.AVIATION /13Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS ARE EXPECTED FOR MUCH OF THE TAF PERIOD...BUT
THERE WILL BE A THREAT OF THUNDERSTORMS.
SUPPORT FOR THUNDERSTORMS WILL BE MAINLY CONVERGENCE INTO A HEAT
TROUGH AND POSSIBLE OUTFLOW BOUNDARIES FROM PREVIOUS CONVECTION.
SOMEWHAT SHALLOW MOISTURE ASSOCIATED WITH THE UPPER-RIDGING
SHOULD LIMIT COVERAGE. THE HRRR AND ARW DISPLAY ISOLATED TO
SCATTERED COVERAGE MAINLY AFTER 200 PM. THE SPC WRF HAS THE
GREATEST THUNDERSTORM COVERAGE AROUND 800 PM. A THREAT OF
THUNDERSTORMS WILL CONTINUE TONIGHT MAINLY BECAUSE OF OUTFLOW
BOUNDARY INTERACTION EARLY. THE MODELS ALSO INDICATE UPPER-LEVEL
LIFT LATE AHEAD OF A MID-LEVEL SHORTWAVE TROUGH. THERE WILL BE A
THUNDERSTORM CHANCE THROUGH THE NIGHT DESPITE NOCTURNAL COOLING.
UNCERTAINTY WAS TOO HIGH TO FORECAST THUNDERSTORMS EXPLICITLY IN
THE TAFS AT ISSUANCE TIME...BUT WE DID INCLUDE A VICINITY MENTION
DURING THE MORE LIKELY TIME OF CONVECTION.
STRONG INSTABILITY WITH CONSIDERABLE CAPE IN THE HAIL GROWTH AREA
INDICATES A THREAT OF STRONG WIND AND HAIL WITH ANY THUNDERSTORMS
THIS AFTERNOON INTO THE EVENING.
OTHER THAN IN SHOWERS...THE THREAT OF FOG IS LOW OVERNIGHT BECAUSE
OF CONTINUED INSTABILITY.
EXTENDED AVIATION OUTLOOK...WIDESPREAD RESTRICTIONS IN SHOWERS
AND THUNDERSTORMS MAY OCCUR SATURDAY AND SATURDAY NIGHT ASSOCIATED
WITH A COLD FRONT MOVING INTO THE AREA.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
99
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1053 AM CDT FRI JUN 26 2015
.UPDATE...
ISSUED AT 1045 AM CDT FRI JUN 26 2015
WILL UPDATE THE FORECAST TO EXPAND THE FLASH FLOOD WATCH FURTHER
NORTH THIS AFTERNOON AND INTO MID EVENING UNTIL 10 PM TO INCLUDE
ALL OF OUR CWA EXCEPT FOR KNOX...STARK AND MARSHALL COUNTIES.
SHOWERS AND THUNDERSTORMS HAVE SPREAD SLOWLY AS FAR NORTH AS
PEORIA BY LATE MORNING WITH HEAVIEST RAINS OVER 1 INCH ALONG A
LEWISTOWN TO PEKIN TO BLOOMINGTON TO DANVILLE LINE. A QUASI
STATIONARY BOUNDARY WAS NEAR I-72 AND EXTENDED TO 1013 MB SURFACE
LOW PRESSURE OVER NE MO BETWEEN KIRKSVILLE AND QUINCY. ANOTHER
1013 MB SURFACE LOW PRESSURE WAS OVER SOUTHEAST MO. HRRR MODEL
HANDLING THIS CONVECTION WELL AND USED THIS MODEL FOR FORECAST
THIS AFTERNOON AND EVENING. SURFACE LOW PRESSURE TO QUICKLY DEEPEN
TO 1006 MB AS IT TRACKS TO NEAR TERRE HAUTE INDIANA BY SUNSET.
HEAVIEST RAINS TO FALL ALONG AND NORTH OF THE LOW PRESSURE TRACK
AND FRONTAL BOUNDARY NORTH OF I-70 WHERE ADDITIONAL 1 INCH OF RAIN
EXPECTED WITH LOCALLY 1 TO 2 MORE INCHES OF RAIN POSSIBLE FROM
I-72 NORTH. SPC ALSO HAS SLIGHT RISK OF SEVERE STORMS THIS
AFTERNOON OVER FAR SE IL SE OF A OLNEY TO ROBINSON LINE FOR 15%
RISK OF DAMAGING WIND GUSTS AND LARGE HAIL AND 2% RISK OF
TORNADOES. ENHANCED SLIGHT RISK WAS SE OF LAWERNCE COUNTY AND
CENTERED OVER KY AND MID/NW TN. HIGHS MOSTLY IN THE MID 70S OVER
CENTRAL IL WITH LOWER 80S IN FAR SOUTHEAST IL AND HUMID WITH
DEWPOINTS IN THE MID 60S TO LOWER 70S.
&&
.SHORT TERM...(TODAY)
ISSUED AT 305 AM CDT FRI JUN 26 2015
08Z/3AM SURFACE ANALYSIS SHOWS LOW PRESSURE NEAR KANSAS CITY...WITH
STATIONARY FRONTAL BOUNDARY EXTENDING E/SE INTO FAR SOUTHERN
ILLINOIS. MCS THAT IMPACTED THE SE KILX CWA EARLIER THIS EVENING
HAS NOW TRACKED INTO CENTRAL/EASTERN KENTUCKY...WHILE A SECOND MCS
HAS DEVELOPED UPSTREAM OVER EASTERN KANSAS INTO WEST-CENTRAL
MISSOURI. THIS SECOND SYSTEM WILL CONTINUE TO TRACK E/SE ALONG THE
SYNOPTIC FRONT/OUTFLOW FROM PREVIOUS COMPLEX INTO SOUTHERN ILLINOIS
LATER THIS MORNING. FURTHER NORTH...STRATIFORM RAIN WITH A FEW
EMBEDDED THUNDERSTORMS WILL SPREAD INTO CENTRAL ILLINOIS FROM THE
WEST. DUE TO EXTENSIVE CLOUD COVER NORTH OF THE FRONT...WILL ONLY
MENTION ISOLATED THUNDER ALONG/NORTH OF THE I-72 CORRIDOR. FURTHER
SOUTH...WILL GO WITH PREDOMINANT THUNDER CLOSER TO THE BOUNDARY AND
THE MORE UNSTABLE AIRMASS ALONG/SOUTH OF I-70. LATEST DAY 1
CONVECTIVE OUTLOOK PLACES THE FAR SOUTHEAST CWA IN A SLIGHT RISK FOR
SEVERE...WITH DAMAGING WIND GUSTS AND LARGE HAIL BEING THE PRIMARY
THREATS LATER TODAY. HEAVIEST RAINFALL WILL ALSO BE FOCUSED ACROSS
THE SOUTHEAST WHERE 1 TO 1.5 INCHES WILL BE LIKELY.
.LONG TERM...(TONIGHT THROUGH THURSDAY)
ISSUED AT 305 AM CDT FRI JUN 26 2015
SHORT-WAVE TROUGH EVIDENT ON CURRENT WATER VAPOR IMAGERY OVER
EASTERN NEBRASKA/KANSAS WILL TRACK EASTWARD INTO INDIANA TONIGHT.
SHOWERS AND A FEW THUNDERSTORMS WILL CONTINUE ALONG/AHEAD OF THIS
FEATURE THIS EVENING...WITH RAIN CHANCES DIMINISHING FROM WEST TO
EAST AFTER MIDNIGHT. ONCE THE WAVE PASSES TO THE EAST AND THE
PERSISTENT FRONTAL BOUNDARY DRAPED ACROSS SOUTHERN ILLINOIS GETS A
GOOD PUSH SOUTHWARD...COOLER AND DRIER WEATHER WILL BE ON TAP FOR
SATURDAY. EVEN WITH MOSTLY SUNNY SKIES...BRISK NORTHERLY FLOW WILL
KEEP TEMPS SEVERAL DEGREES BELOW NORMAL FOR THIS TIME OF YEAR IN THE
MIDDLE TO UPPER 70S.
SYNOPTIC PATTERN THROUGHOUT THE EXTENDED WILL FEATURE A LARGE UPPER
RIDGE OVER THE ROCKIES AND A CORRESPONDING DOWNSTREAM TROUGH ACROSS
THE GREAT LAKES/MIDWEST. WITH THIS PATTERN REMAINING FIRMLY IN PLACE
THROUGH NEXT WEEK...A CONTINUATION OF BELOW NORMAL TEMPERATURES IS
ANTICIPATED ALONG WITH PERIODIC RAIN CHANCES. SEVERAL SHORT-WAVES
WILL DROP INTO THE REGION WITHIN THE BROAD NORTHWESTERLY FLOW
PATTERN...HOWEVER THE EXACT TIMING AND STRENGTH OF THESE FEATURES
WILL BE DIFFICULT TO DETERMINE THIS FAR OUT. BASED ON GFS/ECMWF
CONSENSUS...IT APPEARS TWO DISTINCT PERIODS OF ENHANCED RAIN CHANCES
ARE EMERGING. ONE LATE SUNDAY INTO MONDAY AND ANOTHER LATE TUESDAY
INTO WEDNESDAY. HAVE INCLUDED MENTIONABLE POPS DURING THOSE TIME
FRAMES...THEN HAVE GONE WITH A DRY FORECAST THE REST OF THE TIME.
NEITHER OF THESE TWO SYSTEMS WILL HAVE NEARLY AS MUCH MOISTURE TO
WORK WITH AS RECENT SYSTEMS...SO DESPITE POPS...RAINFALL AMOUNTS
WILL REMAIN LIGHT NEXT WEEK. MAIN STORY WILL THE UNSEASONABLY COOL
CONDITIONS...WITH HIGHS IN THE UPPER 70S AND LOWER 80S THROUGH THE
ENTIRE WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 653 AM CDT FRI JUN 26 2015
LOW STRATUS AND LIGHT TO MODERATE FOG HAS OVERSPREAD THE TAF SITES
THIS MORNING WHILE REMNANTS OF AN MCS WILL BE MOVING ACROSS THE
AERA MOST OF THE DAY. ADDITIONAL DEVELOPMENT BEHIND THIS AREA WILL
ALSO OCCUR...SO RAIN WILL CONTINUE THROUGH THE AFTERNOON AT ALL
TAF SITES. IFR AND LIFR CONDITIONS ARE EXPECTED THROUGH THE
MORNING AND INTO THE AFTERNOON. CONDITIONS SHOULD GRADUALLY
IMPROVE LATE AFTERNOON/EARLY EVENING AT ALL SITES AS THE MCS/LOW
PRESSURE AREA MOVES FURTHER EAST OF THE AREA. PCPN SHOULD END AS
WELL BUT CIGS WILL REMAIN LOW. CONDITIONS FINALLY IMPROVE TO
AROUND VFR AROUND MIDNIGHT.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 10 PM CDT THIS EVENING FOR ILZ029-031-
036>038-040>057-061>063-066>068-071>073.
&&
$$
UPDATE...07
SHORT TERM...BARNES
LONG TERM...BARNES
AVIATION...AUTEN
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
710 AM CDT Fri Jun 26 2015
.SHORT TERM: (Tonight through Friday)
Issued at 322 AM CDT Fri Jun 26 2015
Active elements of large MCS over western MO will continue to move
south and southeast early this morning while the stratiform rain
area will continue to move east. RAP and HRRR continue to support
the solution that stratiform rain area with moderate to occasionally
heavy rain will slowly move east across the CWA today. RAP as well
as the GFS/NAM show strong 850-925 moisture convergence moving from
west to east across the area with PWATS near 2 inches. Will
maintain going flash flood watch given these parameters and the
saturated soils. Both the GFS and NAM show low level moisture
convergence shifting southeast of the CWA by 00Z with the upper
trough shifting east of the CWA by 06Z. Think that that the current
end time of the flash flood watch of 00Z still is okay because the
heavy rain should have ended by then. Rain chances overnight should
be just scattered showers over the southeast half of the CWA after
midnight.
Temperatures will be much cooler today behind the front with cloudy
skies, cold air advection, and rain. Highs in most areas will only
be in the 70s.
Britt
.LONG TERM: (Tonight through Thursday)
Issued at 322 AM CDT Fri Jun 26 2015
(Saturday and Sunday)
Dry weather is expect on Saturday as subsidence sets in behind the
exiting trough. Then chances of showers and thunderstorms increases
Sunday and Sunday night as a shortwave trough dives down embedded in
the northwestly flow aloft. MUCAPES will be in the 1500-2000 J/kg
range and deep layer shear will be in the 30-40kt range which may be
sufficient to produce a few isolated severe storms.
(Monday through Thursday)
Amplified upper pattern will dominate next week with shortwave
troughs moving through the area every other day. This will keep a
chance of showers and thunderstorm in the forecast during the period
with below normal temperatures.
Britt
&&
.AVIATION: (For the 12z TAFs through 12z Saturday Morning)
Issued at 650 AM CDT Fri Jun 26 2015
Area of rain with embedded thunderstorms will continue moving east
across the area today. Have seen visibility drop as low as 3/4SM
in the heaviest thunderstorms, but surprisingly the vast majority
of the area remains VFR. Think some lower ceilings across northern
Missouri will gradually work their way southeast across central
and eastern Missouri into Illinois later this morning...though I
am not certain this will occur. If the ceilings don`t move
southeast..my TAFs are too pessimistic. Rain should slowly come to
an end from northwest to southeast...with perhaps some showers
lingering over parts of eastern Missouri and west
central/southwest Illinois into the evening. Ceiling forecast is
low confidence into the evening, but it looks like there is a
decent chance much of the area will stay MVFR and possibly drop to
IFR range tonight.
Specifics for KSTL:
Heaviest thunderstorms should clear Lambert in the next hour or
so. Until then...there`s a decent threat for heavy rain dropping
visibility to 1-2 miles. Am unsure how long the lighter rain will
last...but it looks like it should stick around until early
afternoon at least. However, if there`s no redevelopment behind
the clearing line currently moving through central Missouri, my
TAF is too pessimistic. Do not have a great deal of confidence in
the ceiling forecast either. Guidance suggests that the lower
ceilings over northern Missouri will drop down into the STL area
later this morning/this afternoon. However, guidance hasn`t been
doing a stellar job, and it looks like the lower ceilings are
having some trouble making southward progress. Again, my TAF may
be too pessimistic if those ceilings don`t start coming south over
the next 2-3 hours.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...FLASH FLOOD WATCH through this evening FOR Audrain MO-Boone MO-
Callaway MO-Cole MO-Franklin MO-Gasconade MO-Jefferson MO-
Knox MO-Lewis MO-Lincoln MO-Marion MO-Moniteau MO-Monroe MO-
Montgomery MO-Osage MO-Pike MO-Ralls MO-Shelby MO-St.
Charles MO-St. Louis City MO-St. Louis MO-Ste. Genevieve MO-
Warren MO.
IL...FLASH FLOOD WATCH through this evening FOR Adams IL-Bond IL-
Brown IL-Calhoun IL-Clinton IL-Fayette IL-Greene IL-Jersey
IL-Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL-
Pike IL-Randolph IL-St. Clair IL-Washington IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
707 AM CDT FRI JUN 26 2015
.SYNOPSIS...
ISSUED AT 336 AM CDT FRI JUN 26 2015
AT 08Z...ISOLATED SHOWERS CONTINUE TO TRAIL TO THE WEST ACROSS
NCTRL NEBR BUT HAVE SHOWN RECENT TRENDS OF SLOWLY DISSIPATING AS
THEY DROP SOUTHWARD. MOST OF THE THUNDERSTORM ACTIVITY RESIDES
ACROSS PARTS OF KS AND MO. UPSTREAM ACROSS THE WRN DAKOTAS...MT
AND WYOMING SKIES ARE CLEAR IN MOST AREAS. TEMPERATURES IN WRN
NEBR RANGE FROM 59 TO 64 DEGREES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 336 AM CDT FRI JUN 26 2015
TODAY...THE H5 UPPER TROUGH AXIS AND ASSOCIATED VORT MAX AT 12Z
TO BE LOCATED IN WRN IA. UPSTREAM...THERE WILL BE CHANNELIZED
VORTICITY TODAY. WHILE THIS WOULD SEEM SUPPORTIVE OF AT LEAST
ISOLATED SHOWERS ACROSS THE ERN HALF OF FA AS INDICATED BY THE
HRRR AND RAP MODELS...LATEST NAM AND GFS ARE DRIER. A CROSS
SECTION ACROSS EASTERN AREAS SHOWS SUFFICIENT MOISTURE AVBL
EXCEPT THAT GENERAL SUBSIDENCE NOTED. CURRENT FCST IS DRY
TODAY...ALTHOUGH ISOLATED SHOWERS WOULD BE POSSIBLE. CURRENT BAND
OF SHOWERS EAST-WEST ACROSS CHERRY COUNTY TO HOLT COUNTY
CONTINUES TO DIMINISH IN COVERAGE AND EXPECTED TO DISSIPATED BY
12Z. THERE IS HOWEVER INCREASING COVERAGE OF STRATUS ACROSS THE
CENTRAL SANDHILLS INCLUDING THEDFORD ATTM. SATELLITE TRENDS SHOWS
AREA IS DEVELOPING TO THE SOUTHWEST WITH MAINLY MID LEVEL CLOUDS
COVERING NCTRL NEBR. ANY STRATUS SHOULD BEGIN TO SCATTER OUT
AFTER 15Z WITH SCT TO BKN STRATOCUMULUS EXPECTED TODAY. HIGHS
TODAY NEAR PREVIOUS FCST FROM 77 TO 81 DEGREES. WINDS STEADY
NORTH TO NORTHEAST 5 TO 10 MPH.
LOOKING SYNOPTICALLY ACROSS THE CONUS...THE UPPER RIDGE WILL
INTENSIFY ACROSS THE WRN CONUS AS THE UPPER TROUGH AMPLIFIES FROM
THE GREAT LAKES INTO THE MID MISSISSIPPI VALLEY. WEAK SURFACE
HIGH PRESSURE WILL BUILD SOUTH FROM THE NRN INTO THE CNTRL
PLAINS.
TONIGHT...UPPER FLOW WILL REMAIN NWRLY AS SURFACE HIGH PRESSURE
RESIDES OVER THE CENTRAL PLAINS. SKIES EXPECTED TO BE MOSTLY
CLEAR AND TEMPERATURES WILL BE COOLER FROM 55 TO 59 DEGREES.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 336 AM CDT FRI JUN 26 2015
THIS WEEKEND INTO THE FIRST OF NEXT WEEK WILL SEE A RIDGE
DOMINATE THE WESTERN CONUS AS A TROUGH DIGS OVER THE GREAT LAKES
REGION. NORTHWEST FLOW ACROSS THE HIGH PLAINS...HOWEVER THE RIDGE
RIDING SHORT WAVES/STORMS ARE EXPECTED TO REMAIN TO THE NORTHEAST
OF THE CWA. TEMPS ABOVE NORMAL /MORE SUMMER LIKE/ WITH HIGHS IN
THE MID 80S TO LOWER 90S.
MONDAY NIGHT INTO TUESDAY A STRONG DISTURBANCE WILL RIDE THE
CREST OF THE RIDGE AND CAUSE A SFC LOW PRESSURE TO DEVELOP ON THE
LEE SIDE OF THE ROCKIES. BY TUESDAY NIGHT THE LOW PRESSURE ALONG
WITH A TRAILING WEAK COLD FRONT WILL SLIDE SOUTH ACROSS THE
CENTRAL/HIGH PLAINS. MODELS STILL DIFFERING ON THE STRENGTH OF
LOW PRESSURE AND HOW STRONG THE CAP WILL BE. THUS STORMS ARE
POSSIBLE BUT THERE IS GREAT UNCERTAINTY. THE LATEST GFS HAS GONE
DRIER WHILE THE ECMWF HAS INCREASED QPF ACROSS THE AREA. ONE
AGREEMENT IS A SLIGHT BOOST OF TEMPS FOR TUESDAY AHEAD OF THE
FRONT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 705 AM CDT FRI JUN 26 2015
SOME LIFR CEILINGS EXIST ACROSS WRN NEBR...MAINLY NEAR THE KLBF
TERMINAL. RECENT LIFR CEILINGS HAVE MOVED SOUTH OF KVTN WITH VFR
CONDITIONS EXPECTED TODAY. AT KLBF...DURATION OF LIFR CEILINGS ARE
PROBLEMATIC. UPSTREAM CONDITIONS AT TIF HAVE IMPROVED TO MVFR AND
THE AREA SURROUNDING KLBF CONTINUES TO MOVE SOUTH. MVFR CEILINGS
ARE FORECAST AT 13Z...IMPROVING TO VFR BY 15Z. WILL NEED TO
MONITOR TRENDS AND MAKE ADJUSTMENTS AS NEEDED.
&&
.HYDROLOGY...
ISSUED AT 336 AM CDT FRI JUN 26 2015
CURRENT FLOOD WARNINGS FOR BRADY ON THE PLATTE RIVER SYSTEM AND
LEWELLEN ON THE NORTH PLATTE RIVER SYSTEM REMAIN IN PLACE. RIVER
LEVELS CONTINUE TO SLOWLY FALL. THE SOUTH PLATTE RIVER AT ROSCOE
IS CURRENTLY JUST BELOW FLOOD STAGE AT 8.9 FEET AND WILL CONTINUE
TO SLOWLY FALL THROUGH EARLY NEXT WEEK WITH THE FLOOD ADVISORY TO
CONTINUE. THE SOUTH PLATTE RIVER AT NORTH PLATTE IS CURRENTLY
NEAR 12.35 FEET AND WILL ALSO SLOWLY FALL THROUGH EARLY NEXT WEEK
WITH THE FLOOD ADVISORY TO CONTINUE. RECENT RAINFALL FROM LAST
EVENING DOES NOT APPEAR TO CAUSE CONCERN FOR ANY RISES...ONLY A
SLIGHTLY LESS FALL IN STAGE IN THE NEAR TERM. RIVER LEVELS ALONG
THE NORTH PLATTE RIVER UPSTREAM OF LAKE MCCONAUGHY ARE ELEVATED
NEAR ACTION STAGE AT LISCO WHILE REMAINING ABOVE MINOR FLOOD
STAGE AT LEWELLEN THROUGH EARLY NEXT WEEK.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...ROBERG
SHORT TERM...ROBERG
LONG TERM...MASEK
AVIATION...ROBERG
HYDROLOGY...ROBERG
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
629 AM CDT FRI JUN 26 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 333 AM CDT FRI JUN 26 2015
THE CHANCE FOR THUNDERSTORMS TODAY IS THE PRIMARY FORECAST CONCERN.
THEN A GENERALLY DRY AND WARMER WEEKEND...WITH THE EXCEPTION OF A
SMALL CHANCE FOR STORMS SUNDAY.
NORTHWEST MID LEVEL FLOW ACROSS THE PLAINS WAS NOTED ON EVENING
UPPER AIR CHARTS AND SHORT TERM MODEL OUTPUT. A COUPLE OF SHORTWAVES
COULD BE IDENTIFIED WITHIN THE FLOW...AND RECENT RAP HEIGHT
FORECASTS ALONG WITH WATER VAPOR IMAGERY SUGGESTED ONE WAVE WAS
MOVING OUT OF SOUTHEAST NEBRASKA AS OF 3 AM...AND ANOTHER WAS
APPROACHING NORTHEAST NEBRASKA FROM SOUTH DAKOTA. BOTH WAVES WERE
TRIGGERING SCATTERED SHOWERS AND STORMS...HOWEVER THE STRONGEST WERE
IN NORTHERN KANSAS WHERE LIFT WAS MAXIMIZED JUST NORTH OF FRONTAL
BOUNDARY EXTENDING FROM KANSAS CITY TO WICHITA.
GIVEN NORTHWEST FLOW ALOFT...SOUTHERN STORMS MOVING OUT OF OUR AREA
WILL REMAIN THERE THIS MORNING. SHORTWAVE TO THE NORTH WILL
GRADUALLY WORK SOUTHEAST TODAY...BUT ABSENCE OF SURFACE BOUNDARY/LOW
LEVEL CONVERGENCE SUGGESTS ACTIVITY WILL REMAIN ISOLATED TO
SCATTERED IN NATURE. IN FACT...MANY SHORT RANGE MESOSCALE MODELS
INCLUDING HRRR AND RAP SUGGEST A DECREASE IN ACTIVITY THROUGH THE
MORNING BEFORE AFTERNOON HEATING HELPS BUBBLE UP WIDELY SCATTERED
AFTERNOON CONVECTION. SO WILL PLAY THE HIGHEST POPS IN NORTHEAST
NEBRASKA THIS MORNING...THEN BROADBRUSH SMALL CHANCES THROUGH THE
AFTERNOON ACROSS MUCH OF EASTERN NEBRASKA AND SOUTHWEST IOWA. COULD
SEE SOME LINGERING SHOWERS/STORMS IN SOUTHEAST NEBRASKA OR SOUTHWEST
IOWA DURING THE EARLY EVENING BEFORE SHORTWAVE PUSHES FARTHER AWAY
AND WE LOSE AFTERNOON HEATING.
OTHERWISE WE WILL SEE A TENDENCY TOWARD NORTHERLY LOW LEVEL FLOW
TONIGHT AND SATURDAY AS HIGH PRESSURE SETTLES ACROSS THE
REGION...AND BRINGS SLIGHTLY DRIER AIR INTO OUR AREA. SHOULD SEE
PLENTY OF SUNSHINE SATURDAY WITH HIGHS IN THE LOWER 80S AFTER
MORNING LOWS IN THE LOWER 60S.
SOUTHERLY FLOW WILL RETURN SATURDAY NIGHT AS A SHORTWAVE DIVES INTO
MINNESOTA THEN EVENTUALLY IOWA/WISCONSIN/ILLINOIS. SURFACE COLD
FRONT WILL FOLLOW THIS WAVE AND SWEEP THROUGH EASTERN NEBRASKA AND
SOUTHWEST IOWA ON SUNDAY. CONVECTION SATURDAY NIGHT SHOULD BE
CONFINED TO AREAS TO OUR NORTHEAST WHERE STRONG WARM ADVECTION IS
REALIZED JUST AHEAD OF MID LEVEL WAVE. ON SUNDAY...AXIS OF BEST LIFT
NEAR SHORTWAVE AND SURFACE REFLECTION WILL STILL LIE WELL TO OUR
EAST AND NORTHEAST IN MINNESOTA AND IOWA...BUT COULD SEE A FEW
SHOWERS OR STORMS NEAR AND EAST OF THE NEBRASKA/IOWA BORDER AS COLD
FRONT SWINGS SOUTHEAST. SHOULD SEE NICE WARMING ON SUNDAY AS
SOUTHWEST FLOW AHEAD AND NORTHWEST FLOW BEHIND FRONT WILL PROMOTE
DECENT MIXING. HIGHS THEN SHOULD EASILY REACH THE MID AND UPPER
80S.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 333 AM CDT FRI JUN 26 2015
GENERAL MID LEVEL FLOW PATTERN CHANGES ONLY A LITTLE DURING THE
WEEK. BROAD HIGH PRESSURE WILL REMAIN OVER THE SOUTHWESTERN STATES
THROUGH THE PERIOD. MEANWHILE UPPER LOW IN THE EASTERN GREAT LAKES
EARLY IN THE PERIOD WILL LIFT TO THE NORTHEAST...LEAVING BROAD
TROUGH BEHIND OVER THE EASTERN HALF OF THE COUNTRY. IN BETWEEN THESE
FEATURES...FLOW IN THE CENTRAL PLAINS WILL SHIFT FROM NEARLY
NORTHERLY TO NORTHWESTERLY BY MID WEEK. SEVERAL IMPULSES RIDING OVER
WESTERN RIDGE WILL ENTER THE PLAINS...BRINGING OFF AND ON
THUNDERSTORM CHANCES TO OUR REGION. GFS AND ECMWF ARE IN FAIRLY GOOD
AGREEMENT WITH THIS OVERALL PATTERN CHANGE...BUT DIFFER ON TIMING OF
PRECIPITATION-PRODUCING SHORTWAVES.
HOWEVER BOTH MODELS ARE RELATIVELY SIMILAR IN DROPPING A MORE
SIGNIFICANT SHORTWAVE INTO THE PLAINS ON TUESDAY...INCREASING
THUNDERSTORM CHANCES IN EASTERN NEBRASKA AND WESTERN IOWA TUESDAY
NIGHT AS ATTENDANT SURFACE LOW AND FRONTAL SYSTEM MOVE THROUGH THE
REGION. WILL HAVE THE HIGHEST PRECIP CHANCES AT THIS TIME...THOUGH
STILL ONLY IN THE CHANCE CATEGORY AS MOISTURE RETURN AFTER SUNDAY
COLD FRONT WILL BE SLOW TO OCCUR. SHOULD SEE MINIMAL RAIN CHANCES
BEHIND THIS SYSTEM ON WEDNESDAY AND THURSDAY...BUT GIVEN UNCERTAINTY
IN SMALL-SCALE MID LEVEL FEATURES...CAN NOT RULE OUT A STRAY STORM
OR TWO. OTHERWISE EXPECT TEMPERATURES TO AVERAGE 60S AND 80S FOR
LOWS AND HIGHS THROUGH THE PERIOD.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 627 AM CDT FRI JUN 26 2015
SHOWERS ARE AFFECTING KOFK THIS MORNING AND MAY AFFECT KOMA/KLNK
THROUGH THE MORNING HOURS...WITH BRIEF MVFR VIS POSSIBLE. A FEW
SHOWERS/STORMS ARE POSSIBLE IN THE AREA THIS AFTERNOON...BUT WITH
LOW CONFIDENCE ON DEVELOPMENT AND COVERAGE...HAVE LEFT MENTION OUT
OF TAFS. OTHERWISE...WILL SEE A CLEARING TREND TONIGHT...WITH
WINDS BECOMING LIGHT AND VARIABLE THROUGH SATURDAY MORNING.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...DERGAN
LONG TERM...DERGAN
AVIATION...MAYES
AREA FORECAST DISCUSSION
NWS BISMARCK ND
834 AM CDT FRI JUN 26 2015
.UPDATE...
ISSUED AT 829 AM CDT FRI JUN 26 2015
GIVEN A TIME LAGGED ENSEMBLE OF THE 09-11 UTC HRRR ITERATIONS AND
A CONSENSUS OF THE 00 UTC WRF-ARW/NMM AND 06 UTC NAM...DECREASED
THE OVERALL MENTION OF ISOLATED THUNDERSTORMS ACROSS CENTRAL
NORTH DAKOTA TODAY...CONFINING THE MENTION TO PRIMARILY THE TURTLE
MOUNTAINS THROUGH THE JAMES RIVER VALLEY.
UPDATE ISSUED AT 639 AM CDT FRI JUN 26 2015
MAIN ADJUSTMENT TO THE FORECAST WAS TO ADD ISOLATED SHOWERS IN THE
JAMES RIVER VALLEY THIS MORNING. KBIS WSR-88D SHOWS A FEW SHOWERS
IN THAT AREA...AND THE LATEST HRRR HINTS THAT THEY COULD PERSIST
FOR A FEW HOURS. PATCHY FOG WAS LEFT IN PLACE WITH A FEW SPOTS
ACROSS WESTERN AND CENTRAL NORTH DAKOTA REPORTING REDUCED
VISIBILITIES. DID NOT ADJUST POPS FOR THIS AFTERNOON WITH ISOLATED
TO SCATTERED SHOWERS / THUNDERSTORMS STILL SUPPORTED IN THE HRRR
AND 26.06Z NAM.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CDT FRI JUN 26 2015
THE LATEST WATER VAPOR IMAGERY DEPICTS A NORTHWEST FLOW INTO
NORTH DAKOTA WITH THE NEXT SIGNIFICANT UPSTREAM SHORTWAVE TROUGH
WORKING THROUGH CENTRAL BRITISH COLUMBIA. THIS SHORTWAVE TROUGH
WILL MOVE EAST THEN PIVOT SOUTHEAST AS IT SLIDES INTO SOUTH CENTRAL
MANITOBA 12Z SATURDAY. IN RESPONSE...A SURFACE LOW PRESSURE AND
ASSOCIATED COLD FRONT WILL EMERGE OVER SOUTHERN ALBERTA/SASKATCHEWAN
INTO NORTHERN MONTANA FRIDAY EVENING/NIGHT. THE COLD FRONT WILL
ENTER NORTHWESTERN NORTH DAKOTA AROUND 12Z SATURDAY. IN ADVANCE OF
THIS SYSTEM FOR TODAY(FRIDAY)...A COUPLE OF SUBTLE SHORTWAVES
STRETCHING FROM SOUTHERN/EASTERN SASKATCHEWAN INTO CENTRAL NORTH
DAKOTA WILL HELP PRODUCE ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS DURING THE AFTERNOON/EVENING. CAPE/SHEAR VALUES
REMAIN WEAK AND THE LATEST HIGH RESOLUTION MODELS...ARW WEST/NMM
WEST/HRRR...PORTRAY ISOLATED TO SCATTERED SHOWERS/THUNDERSTORMS...MAINLY
FROM THE TURTLE MOUNTAINS SOUTH INTO THE JAMES RIVER VALLEY. THE
GLOBAL MODELS EXTEND PRECIPITATION CHANCES ACROSS CENTRAL NORTH
DAKOTA WITH THE FAR WEST REMAINING DRY. USED A BLEND OF THE HIGH
RESOLUTION AND GLOBAL SUITE FOR POPS TODAY...AS THE SHORTWAVES
INTERACT WITH THE WEAK INSTABILITY ALREADY IN PLACE THIS AFTERNOON
AND EVENING. THE ISOLATED SHOWERS/THUNDERSTORMS WILL CONTINUE
FRIDAY NIGHT AS A WEAK LOW LEVEL/850MB JET BRIEFLY DEVELOPS FRIDAY
EVENING ADVECTING IN MOISTURE AHEAD OF THE AFOREMENTIONED
SHORTWAVE TROUGH AND SURFACE FRONT. HOWEVER NOT EXPECTING ANY
SEVERE WEATHER AT THIS TIME...AND SPC CONVECTIVE OUTLOOK
HIGHLIGHTS GENERAL THUNDERSTORMS FRIDAY/FRIDAY NIGHT. HIGH
TEMPERATURES FRIDAY AFTERNOON WILL BE IN THE LOW TO MID 80S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 308 AM CDT FRI JUN 26 2015
A WEAK COLD FRONT MOVING ACROSS THE NORTHERN PLAINS COULD BRING A
CHANCE OF THUNDERSTORMS ON SATURDAY. THE MAIN CHANCES SHOULD BE IN
THE EASTERN PART OF THE FORECAST AREA WITH THE BOUNDARY REACHING
THAT AREA SATURDAY AFTERNOON DURING PEAK HEATING. THE THUNDERSTORM
CHANCES ARE EXPECTED TO DIMINISH IN THE EVENING AS THE BOUNDARY
EXITS THE REGION.
DRY WEATHER IS EXPECTED SUNDAY AND MONDAY WITH H5 HEIGHTS BUILDING
ACROSS NORTH DAKOTA. BY MONDAY NIGHT...THE FIRST IN A SERIES OF
UPPER WAVES MOVES ACROSS IN NORTHWESTERLY FLOW ALOFT. WILL FOLLOW
THE MODEL BLEND IN REGARDS TO POPS WHICH BRINGS SMALL CHANCES OF
THUNDERSTORMS ACROSS AT LEAST PARTS OF WESTERN AND CENTRAL NORTH
DAKOTA FROM MONDAY NIGHT AND BEYOND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 829 AM CDT FRI JUN 26 2015
MORNING FOG IS QUICKLY BURNING OFF ACROSS WESTERN AND CENTRAL
NORTH DAKOTA AS OF 1330 UTC. OTHERWISE...VFR CONDITIONS ARE
EXPECTED TODAY WITH SURFACE HIGH PRESSURE. ISOLATED THUNDERSTORMS
MAY BE POSSIBLE IN THE KJMS VICINITY THIS AFTERNOON. FOG WILL ONCE
AGAIN BE POSSIBLE TONIGHT FOR KBIS/KJMS. GIVEN UNCERTAINTY...WILL
LEAVE THE MENTION OUT FOR NOW.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...KS
LONG TERM...CK
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
639 AM CDT FRI JUN 26 2015
.UPDATE...
ISSUED AT 639 AM CDT FRI JUN 26 2015
MAIN ADJUSTMENT TO THE FORECAST WAS TO ADD ISOLATED SHOWERS IN THE
JAMES RIVER VALLEY THIS MORNING. KBIS WSR-88D SHOWS A FEW SHOWERS
IN THAT AREA...AND THE LATEST HRRR HINTS THAT THEY COULD PERSIST
FOR A FEW HOURS. PATCHY FOG WAS LEFT IN PLACE WITH A FEW SPOTS
ACROSS WESTERN AND CENTRAL NORTH DAKOTA REPORTING REDUCED
VISIBILITIES. DID NOT ADJUST POPS FOR THIS AFTERNOON WITH ISOLATED
TO SCATTERED SHOWERS / THUNDERSTORMS STILL SUPPORTED IN THE HRRR
AND 26.06Z NAM.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CDT FRI JUN 26 2015
THE LATEST WATER VAPOR IMAGERY DEPICTS A NORTHWEST FLOW INTO
NORTH DAKOTA WITH THE NEXT SIGNIFICANT UPSTREAM SHORTWAVE TROUGH
WORKING THROUGH CENTRAL BRITISH COLUMBIA. THIS SHORTWAVE TROUGH
WILL MOVE EAST THEN PIVOT SOUTHEAST AS IT SLIDES INTO SOUTH CENTRAL
MANITOBA 12Z SATURDAY. IN RESPONSE...A SURFACE LOW PRESSURE AND
ASSOCIATED COLD FRONT WILL EMERGE OVER SOUTHERN ALBERTA/SASKATCHEWAN
INTO NORTHERN MONTANA FRIDAY EVENING/NIGHT. THE COLD FRONT WILL
ENTER NORTHWESTERN NORTH DAKOTA AROUND 12Z SATURDAY. IN ADVANCE OF
THIS SYSTEM FOR TODAY(FRIDAY)...A COUPLE OF SUBTLE SHORTWAVES
STRETCHING FROM SOUTHERN/EASTERN SASKATCHEWAN INTO CENTRAL NORTH
DAKOTA WILL HELP PRODUCE ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS DURING THE AFTERNOON/EVENING. CAPE/SHEAR VALUES
REMAIN WEAK AND THE LATEST HIGH RESOLUTION MODELS...ARW WEST/NMM
WEST/HRRR...PORTRAY ISOLATED TO SCATTERED SHOWERS/THUNDERSTORMS...MAINLY
FROM THE TURTLE MOUNTAINS SOUTH INTO THE JAMES RIVER VALLEY. THE
GLOBAL MODELS EXTEND PRECIPITATION CHANCES ACROSS CENTRAL NORTH
DAKOTA WITH THE FAR WEST REMAINING DRY. USED A BLEND OF THE HIGH
RESOLUTION AND GLOBAL SUITE FOR POPS TODAY...AS THE SHORTWAVES
INTERACT WITH THE WEAK INSTABILITY ALREADY IN PLACE THIS AFTERNOON
AND EVENING. THE ISOLATED SHOWERS/THUNDERSTORMS WILL CONTINUE
FRIDAY NIGHT AS A WEAK LOW LEVEL/850MB JET BRIEFLY DEVELOPS FRIDAY
EVENING ADVECTING IN MOISTURE AHEAD OF THE AFOREMENTIONED
SHORTWAVE TROUGH AND SURFACE FRONT. HOWEVER NOT EXPECTING ANY
SEVERE WEATHER AT THIS TIME...AND SPC CONVECTIVE OUTLOOK
HIGHLIGHTS GENERAL THUNDERSTORMS FRIDAY/FRIDAY NIGHT. HIGH
TEMPERATURES FRIDAY AFTERNOON WILL BE IN THE LOW TO MID 80S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 308 AM CDT FRI JUN 26 2015
A WEAK COLD FRONT MOVING ACROSS THE NORTHERN PLAINS COULD BRING A
CHANCE OF THUNDERSTORMS ON SATURDAY. THE MAIN CHANCES SHOULD BE IN
THE EASTERN PART OF THE FORECAST AREA WITH THE BOUNDARY REACHING
THAT AREA SATURDAY AFTERNOON DURING PEAK HEATING. THE THUNDERSTORM
CHANCES ARE EXPECTED TO DIMINISH IN THE EVENING AS THE BOUNDARY
EXITS THE REGION.
DRY WEATHER IS EXPECTED SUNDAY AND MONDAY WITH H5 HEIGHTS BUILDING
ACROSS NORTH DAKOTA. BY MONDAY NIGHT...THE FIRST IN A SERIES OF
UPPER WAVES MOVES ACROSS IN NORTHWESTERLY FLOW ALOFT. WILL FOLLOW
THE MODEL BLEND IN REGARDS TO POPS WHICH BRINGS SMALL CHANCES OF
THUNDERSTORMS ACROSS AT LEAST PARTS OF WESTERN AND CENTRAL NORTH
DAKOTA FROM MONDAY NIGHT AND BEYOND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 639 AM CDT FRI JUN 26 2015
PATCHY FOG IS POSSIBLE AT KDIK/KISN/KBIS THROUGH 15Z FRIDAY.
OTHERWISE VFR CIGS/VSBYS NEXT 24HR. HELD ONTO VCTS AT KMOT/KBIS/KJMS
FROM 22Z FRIDAY THROUGH 04Z SATURDAY. ANY SHOWER OR THUNDERSTORM
THAT DEVELOPS WILL BE ISOLATED.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CK
SHORT TERM...KS
LONG TERM...CK
AVIATION...KS
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1038 AM EDT FRI JUN 26 2015
.SYNOPSIS...
A LOW PRESSURE CENTER WILL APPROACH TODAY AND TONIGHT...BRINGING A
WARM FRONT NORTHWARD ACROSS THE AREA TONIGHT. THE LOW WILL PULL A
COLD FRONT ACROSS THE AREA SATURDAY. NEXT FRONT EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
1030 AM UPDATE...
EVALUATING THE 12Z NAM AS IT COMES IN...AND LOOKS A LITTLE TOO
ACTIVE IN THE NEAR TERM...LIKE YESTERDAY. HAVE WEAKER LOW LEVEL
FLOWS IN PLACE...AND LIKE THE LOOKS OF THE HRRR RIGHT NOW THAT
HAVE A BREAK IN THE CONVECTION FOR A FEW HOURS.
PREV DISCN...
A LOW PRESSURE CENTER OVER THE CENTRAL PLAINS EARLY THIS MORNING
WILL MOVE E AND DEEPEN...REACHING W CENTRAL OHIO BY DAWN SAT. THE
ASSOCIATED UPPER LEVEL S/W TROUGH DEEPENS AND ACTUALLY CLOSES OFF
DURING THIS TIME.
CONVECTIVE COMPLEX MOVING INTO THE AREA EARLY THIS MORNING WAS
ASSOCIATED WITH WARM / THETA E ADVECTION AHEAD OF THE APPROACHING
SYSTEM...AND WILL LIKELY HOLD TOGETHER AT LEAST SOMEWHAT BEFORE
BREAKING UP LATER THIS MORNING. MODELS KEEP WARM FRONT S OF THE
AREA MOST OF THE DAY TODAY...NOT PUSHING N IN EARNEST UNTIL LATE
TODAY AND TONIGHT...IN RESPONSE TO STRENGTHENING LOW TO MID LEVEL
S TO SW FLOW AHEAD OF THE APPROACHING LOW CENTER. THIS BRINGS TO
QUESTION THE NATURE OF CONVECTION THIS AFTERNOON...WHICH IS LIKELY
TO BE MOST INTENSE ACROSS THE FAR S.
WARM ADVECTION PRECIPITATION SHOULD BECOME MORE WIDESPREAD ACROSS
THE AREA LATE TODAY BEFORE SHIFTING N TONIGHT...ALLOWING FOR
BREAKS IN PRECIPITATION AT LEAST ACROSS EASTERN PORTIONS OF THE
AREA. CONVECTION OUT AHEAD OF THE COLD FRONT SHOULD THEN SPREAD W
TO E ACROSS THE AREA OVERNIGHT TONIGHT.
WITH MULTIPLE ROUNDS OF CONVECTION AND PW VALUES 1.5 TO AT TIMES
CLOSE TO TWO INCHES...FLASH FLOODING IS A CONCERN...AND A FLASH
FLOOD WATCH IS ISSUED FOR 2 PM TODAY THROUGH SAT. NOTWITHSTANDING
THE CONVECTION THIS MORNING...WHICH WILL PRIME SRN AND PERHAPS
CENTRAL PORTIONS OF THE CWA...THE THREAT THIS AFTERNOON COULD
MATERIALIZE IF WARM FRONTAL PRECIPITATION MANAGES TO BE PERSISTENT
ALTHOUGH THAT MAY BE MORE OF A STRAIGHT FLOOD THREAT OR JUST A
PRIMER FOR TONIGHT.
CONVECTION AHEAD OF THE COLD FRONT COULD THEN BRING THE POTENTIAL
FOR FLASH FLOODING TONIGHT ALTHOUGH THE MODELS APPEAR TO STABILIZE
THE ATMOSPHERE IN THE WARM SECTOR FAIRLY QUICKLY AFTER SUNSET. FFA
IS ISSUED AREA WIDE ALTHOUGH THE THREAT IS LIKELY TO BE PIECEMEAL
IN NATURE. THE WPC SLIGHT RISK FOR EXCESSIVE RAINFALL FOR TODAY
AND TONIGHT IS MAINLY N OF WHERE THE WARM FRONT WILL BE MOST OF
TODAY.
AFTER THE QUICKLY WANING THREAT EARLY THIS MORNING...THE SEVERE
THREAT IS GREATEST IN OUR FAR SRN ZONES THIS AFTERNOON BEFORE
SPREADING NWD AHEAD OF THE COLD FRONT TONIGHT. THE THREAT TONIGHT
IS HIGHEST IN THE W EARLY ON...WITH A DIMINISHING THREAT OVERALL
OVERNIGHT TONIGHT. THE SLIGHT RISK OUTLOOK FROM SPC REFLECTS BOTH
OF THESE FACTORS AS IT IS PLACED ACROSS SRN AND CENTRAL PORTIONS
OF THE FCST AREA...WITH AN ENHANCED THREAT OVER SWRN PORTIONS OF
THE AREA.
A BIAS CORRECTED CONSENSUS BLEND WAS USED FOR TEMPERATURES
ALTHOUGH THE BUST POTENTIAL IS THAT A CLOUDY...WETTER DAY WOULD
HOLD HIGH TEMPERATURES DOWN.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
NO SIGNIFICANT CHANGES MADE TO THE PREVIOUS FORECAST. A STRONG
COLD FRONT WILL SWEEP ACROSS THE AREA ON SATURDAY AS LOW PRESSURE
LIFTS NORTHEAST ACROSS THE AREA. FRONT WILL BE TO THE EAST OF THE
CWA BY SATURDAY AFTERNOON OR EVENING. COULD BE SEVERE WEATHER ON
SATURDAY...MAINLY ACROSS THE EASTERN ZONES...BUT CANT BE
COMPLETELY RULED OUT OTHER PLACES AS WELL. IN ADDITION...GUSTY
WINDS EXPECTED ACROSS THE AREA ON SATURDAY AS THE LOW AND
ASSOCIATED FRONT PUSH THROUGH THE AREA.
LOW WILL CONTINUE TO PUSH OFF TO THE NORTHEAST SATURDAY NIGHT AND
SUNDAY. AREA WILL BE IN A COOL MOIST PATTERN ON SUNDAY...WITH SOME
LIGHT SHOWERS CONTINUING ON SUNDAY...PARTICULARLY ACROSS THE
MOUNTAINS AND NORTHERN WV/SOUTHEAST OHIO ZONES IN THE NW FLOW.
BRIEF HIGH PRESSURE WILL BUILD IN LATER IN THE DAY SUNDAY...FOR
SOME GRADUAL CLEARING/DRYING...PARTICULARLY ACROSS THE WEST AND
SOUTH.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
GIVEN THE CONTINUATION OF A SERIES OF UPPER TROUGHS AND FRONTS
MOVING ACROSS THE AREA NEXT WEEK...WILL GENERALLY KEEP THIS
PERIOD UNSETTLED. HARD TO TIME THESE SYSTEMS...SO WILL BROADBRUSH
AND KEEP CHANCE POPS FOR SHOWERS AND STORMS FOR EACH DAY NEXT
WEEK. TEMPERATURES WILL CONTINUE TO BE MODERATE DUE TO THE CLOUDS
AND SHOWERS...EVEN AS THE COOLER CANADIAN AIRMASS EXITS EAST BY
MONDAY.
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
MORNING CONVECTIVE COMPLEX ASSOCIATED WITH A WARM FRONT WAS MOVING
OUT AND DISSIPATING JUST AS QUICKLY. MVFR CONDITIONS OR BETTER
EXPECTED FROM WHAT IS LEFT.
THE FRONT WILL STAY S OF THE TAF SITES TODAY...SO AFTER A MIDDAY
BREAK...THE SHOWERS AND THUNDERSTORMS MAY REFIRE THIS AFTERNOON
BRINGING OCCASIONAL MVFR TO PERHAPS IFR CONDITIONS.
A COLD FRONT AND LOW PRESSURE SYSTEM WILL BRING EVEN MORE
WIDESPREAD SHOWERS AND THUNDERSTORMS TONIGHT THAT WILL LIKELY
EVENTUALLY BRING IFR CONDITIONS OVERNIGHT TONIGHT.
SFC FLOW WILL BE VARIABLE TO LIGHT W ACROSS NRN SITES AND
MOUNTAINS OVERNIGHT TODAY AND VARIABLE TO LIGHT E ELSEWHERE
BECOMING LIGHT E TO SE EVERYWHERE TONIGHT. LIGHT W TO NW FLOW
ALOFT THIS MORNING WILL BECOME LIGHT SW THIS AFTERNOON AND
EVENING AND THEN MODERATE TO STRONG SW OVERNIGHT TONIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z SATURDAY...
FORECAST CONFIDENCE: LOW.
ALTERNATE SCENARIOS: CONDITIONS IN SHOWERS AND THUNDERSTORMS WILL
VARY.
AFTER 12Z SATURDAY...POSSIBLE IFR IN SHOWERS AND THUNDERSTORMS
SAT.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FLASH FLOOD WATCH FROM 2 PM EDT THIS AFTERNOON THROUGH
SATURDAY AFTERNOON FOR WVZ005>011-013>020-024>040-046-047.
OH...FLASH FLOOD WATCH FROM 2 PM EDT THIS AFTERNOON THROUGH
SATURDAY AFTERNOON FOR OHZ066-067-075-076-083>087.
KY...FLASH FLOOD WATCH FROM 2 PM EDT THIS AFTERNOON THROUGH
SATURDAY AFTERNOON FOR KYZ101>103-105.
VA...FLASH FLOOD WATCH FROM 2 PM EDT THIS AFTERNOON THROUGH
SATURDAY AFTERNOON FOR VAZ003-004.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...TRM/26
SHORT TERM...SL
LONG TERM...JMV
AVIATION...TRM
AREA FORECAST DISCUSSION...UPDATED
NWS MEDFORD OR
0850 AM PDT FRI JUN 26 2015
.UPDATED MARINE DISCUSSION.
.DISCUSSION...A HOT AND UNSTABLE AIR MASS WILL PERSIST OVER THE
REGION DURING THE NEXT WEEK. LOW PRESSURE OFFSHORE FROM CALIFORNIA
AND HIGH PRESSURE CENTERED IN THE GREAT BASIN ARE THE MAIN UPPER
LEVEL FEATURES AFFECTING OUR WEATHER IN THE SHORT TERM WITH THAT
STRONG RIDGING LIKELY TO PERSIST THROUGH THE WEEK.
TODAY AND SATURDAY WILL BE THE HOTTEST DAYS WITH RECORD HIGHS LIKELY
TO BE SET. BUT, THE FOLLOWING FIVE DAYS WILL NOT BE THAT MUCH
COOLER. THE FORECAST HAS BEEN CONSISTENT IN EXPECTING VALLEY HIGHS
DURING THE NEXT TWO DAYS OF 95 TO 110 DEGREES ON THE WEST SIDE OF
THE CASCADES THIS AFTERNOON AND 92 TO 102 ON THE EAST SIDE.
THE OTHER MAIN FOCUS OF THE FORECAST IS THE DEVELOPMENT OF
THUNDERSTORMS WITH THE POTENTIAL FOR LIGHTNING TO CAUSE NEW FIRES.
ATMOSPHERIC MOISTURE LEVELS WILL GRADUALLY INCREASE WITH
PRECIPITABLE WATER AMOUNTS THAT WERE AT 0.50 TO 0.75 INCHES
YESTERDAY TO RISE TO 0.75 TO 1.00 INCHES TODAY. THE LEAST AMOUNT
OF RAINFALL WITH THUNDERSTORMS WILL BE IN THOSE THAT DEVELOP SOUTH
AND EAST OF SOUTHWEST OREGON. AN EARLY AFTERNOON THUNDERSTORM
CANNOT BE COMPLETELY RULED OUT, BUT THERE IS GOOD MODEL AGREEMENT
BETWEEN THE NAM AND THE SREF AND RAP SHORT TERM MODELS THAT THE
FIRST THUNDERSTORMS WILL DEVELOP AROUND 3 PM OVER THE HIGHER
TERRAIN FROM WESTERN SISKIYOU COUNTY TO THE SISKIYOU MOUNTAINS AND
CASCADES EASTWARD. COVERAGE OF STORMS WILL INCREASE DURING THE
EVENING WITH A PRIMARY FOCUS FOR NORTHWARD MOVING THUNDERSTORMS
FROM THE FOOTHILLS OF THE CASCADES (IN EASTERN PORTIONS OF JACKSON
AND DOUGLAS COUNTIES) EASTWARD. THAT WILL NOT BE THE EXCLUSIVE
LOCATION OF THUNDERSTORMS, JUST THE LIKELY FOCUS. THESE STORMS
WILL BE MOVING AT 10 TO 15 KNOTS. EMBEDDED SHORTWAVES IN THE
SOUTHERLY FLOW ALOFT ARE EXPECTED TO KEEP THUNDERSTORMS GOING
OVERNIGHT INTO SATURDAY MORNING WITH THE HIGHEST PROBABILITY ALONG
THE CASCADES. THERE IS UNCERTAINTY IN THE TRACK AND STRENGTH OF
SHORTWAVES AS THE GFS HAS A FOCUS DURING THE EVENING HOURS BEFORE
LIFTING THE MAJORITY OF ACTIVITY INTO NORTHERN OREGON WHILE THE
NAM SOLUTION WOULD ACTUALLY INCREASE THE NUMBER OF THUNDERSTORMS
IN OUR AREA DURING THE OVERNIGHT HOURS WHILE SPREADING THEM IN A
SOUTHEAST RATHER THAN SOUTH FLOW ALOFT TO THE COAST AND COASTAL
WATERS.
THUNDERSTORMS ON SATURDAY WILL PRODUCE MORE RAINFALL BUT THEY WILL
ALSO BE FASTER MOVING AT 15 TO 25 KNOTS. THUNDERSTORM COVERAGE IS
EXPECTED TO BE AT ITS PEAK DURING SATURDAY AFTERNOON AND EVENING.
THE PERSISTENT PATTERN WILL ONCE AGAIN PRODUCE NOCTURNAL
THUNDERSTORMS SATURDAY NIGHT INTO SUNDAY MORNING.
THERE IS UNCERTAINTY IN THE TIMING AND TRACK OF THE OFFSHORE LOW.
THE NAM IS FASTER THAN THE GFS BUT BOTH HAVE IT MOVING NORTH TO
THE SOUTHERN OREGON COAST ON SUNDAY. THIS WILL BRING IN SLIGHTLY
COOLER AIR AND EVENTUALLY KICK THE CONVECTIVE ACTIVITY TO THE
EAST WITH WEST SIDE OF THE CASCADES FOCUS OF THUNDERSTORMS ON
SUNDAY MORNING SHIFTING TO THE EAST SIDE FOR SUNDAY EVENING INTO
MONDAY. THUNDERSTORMS ON SUNDAY WILL HAVE A HIGHER PROBABILITY OF
PRODUCING SEVERE WIND GUSTS. THE TROUGH WITH A MUCH DRIER AIR
MASS WILL BE IN PLACE OVER THE PACIFIC NORTHWEST ON MONDAY. THUS,
A SLIGHT CHANCE OF THUNDERSTORMS WILL BE NEARLY LIMITED TO ONLY
LAKE AND MODOC COUNTIES. MONDAY NIGHT SHOULD TRANSPIRE WITHOUT
THUNDERSTORMS.
RIDGING FROM THE GREAT BASIN IS EXPECTED TO REBUILD INTO OUR AREA
TUESDAY FOR THE START OF ANOTHER WARMING TREND INTO THURSDAY.
THIS WILL ALSO SEND HIGHER AMOUNTS OF MOISTURE INTO THE EAST SIDE
ON TUESDAY THAT WILL EXPAND FARTHER WEST...TO THE WEST SIDE ON
WEDNESDAY FOR ANOTHER EPISODE OF A SLIGHT CHANCE OF AFTERNOON AND
EVENING THUNDERSTORMS. THE PROBABILITY WILL BE THE LOWEST FOR THE
COAST AND DOUGLAS COUNTY.
FORECAST UNCERTAINTY INCREASES BEYOND WEDNESDAY AS THE ECMWF MODEL
INDICATES A STRONG TROUGH MOVING INTO THE PACIFIC NORTHWEST WILL
FINALLY CHANGE THE PATTERN AND BRING SOME COOLING FOR THE END OF
THE WEEK, BUT THE GFS IS PERSISTENT AND LEAVES THE HOT GREAT
BASIN RIDGE IN COMMAND. FOR NOW, WE WILL LEAN TOWARD PERSISTENCE.
&&
.AVIATION...FOR THE 26/12Z TAF CYCLE...LOW CLOUDS WILL CONTINUE
ALONG THE NORTH COAST WITH IFR TO LIFR CIGS THIS MORNING GRADUALLY
RISING TO MVFR THIS AFTERNOON. ELSEWHERE VFR CONDITIONS WILL
PREVAIL.
LATE THIS AFTERNOON INTO THE EVENING ISOLATED THUNDERSTORMS ARE
EXPECTED ALONG AND NEAR THE OREGON CASCADES...THE UPPER KLAMATH
BASIN...AND WESTERN SISKIYOU COUNTY. THE BEST CHANCE OF
THUNDERSTORMS IS IN THE 00-06Z TIME FRAME FOR THIS TAF CYCLE AT KLMT
AND KRBG. THESE STORMS ARE EXPECTED TO BE HIGH-BASED, DRY, AND
THEREFORE COULD CONTAIN GUSTY OUTFLOW WINDS AND POSSIBLY ISOLATED
MICROBURSTS. BTL/SPILDE
&&
.MARINE...UPDATED 900 AM PDT FRIDAY 26 JUNE 2015...A THERMAL TROUGH
WILL BRING GALE FORCE NORTH WINDS SOUTH OF CAPE BLANCO TODAY WITH
VERY STEEP WIND WAVE DOMINATED SEAS. AS IS TYPICAL WITH THERMAL
TROUGH WIND PATTERNS...CONFIDENCE IS ONLY MODERATE ON EXACTLY HOW
CLOSE TO SHORE THE GALES REACH...WITH THE FORECAST REFLECTING GALES
BEYOND 10 NM FROM SHORE TODAY. THE THERMAL TROUGH WILL WEAKEN AND
BOTH WINDS AND SEAS ARE EXPECTED TO LOWER THIS WEEKEND.
THUNDERSTORMS ARE POSSIBLE TONIGHT INTO SATURDAY MORNING WITHIN 10
NM FROM SHORE. THE THERMAL TROUGH WILL THEN STRENGTHEN AGAIN MONDAY
AND TUESDAY WITH CONDITIONS AT LEAST HAZARDOUS TO SMALL CRAFT.
STRONGEST WINDS AND SEAS WILL AGAIN BE SOUTH OF CAPE BLANCO.
SK/SPILDE
&&
.FIRE WEATHER...UPDATED 400 AM PDT FRIDAY 26 JUNE 2015...HAVE MADE
NO CHANGES WITH RESPECT TO THE RED FLAG WARNING (RFWMFR) HEADLINES
IN PLACE ACROSS THE AREA BEGINNING LATER THIS AFTERNOON. MODELS
CONTINUE TO SHOW MOISTURE INCREASING IN THE SOUTH TO SOUTHEAST FLOW
DEVELOPING ALOFT IN A CORRIDOR BETWEEN AN UPPER LOW OFFSHORE AND THE
MID LEVEL RIDGE CENTERED OVER THE GREAT BASIN. THIS IS A FAVORABLE
THUNDERSTORM PATTERN AND THIS CORRIDOR IS AIMED RIGHT OVER SW
OREGON/NORCAL, WHERE ISOLATED TO SCATTERED THUNDERSTORMS ARE
EXPECTED TO DEVELOP LATER THIS AFTERNOON AND EVENING. THIS PATTERN
WILL PERSIST FRIDAY NIGHT THROUGH MUCH OF THE WEEKEND AS THE UPPER
LOW SLOWLY MOVES NORTHWARD ALONG THE CALIFORNIA COAST.
CONFIDENCE ON THE EXACT LOCATION OF STORMS REMAINS FAIRLY LOW AS MID
AND UPPER LEVEL SUPPORT FOR STORMS (SHORTWAVES) IS WEAK, BUT WITH
STRONG HEATING AND THE RESULTING INSTABILITY OVER ABNORMALLY DRY
FUELS ACROSS A LARGE PART OF THE AREA (NEAR-RECORD DRYNESS ALONG THE
COAST)...THE THREAT FOR ABUNDANT LIGHTNING IS A BIG CONCERN FOR
INITIAL ATTACK. STORMS SHOULD INITIATE OVER THE HIGHER TERRAIN THIS
AFTERNOON, THEN PROPAGATE NORTHWESTWARD WITH TIME THIS EVENING AND
OVERNIGHT. A STRONG MOISTURE GRADIENT WILL EXIST ALONG THE CASCADES.
STORMS OVER THE EAST SIDE SHOULD BE FAIRLY DRY, WHERE PWS ARE
GENERALLY LESS THAN 0.75 OF AN INCH. PWS OF 1.00-1.25 INCHES EXIST
ALONG AND WEST OF THE CASCADES WHERE STORMS THAT DEVELOP SHOULD BE
COMPARABLY WETTER. ANY STORMS WILL HAVE THE ABILITY TO PRODUCE GUSTY
OUTFLOWS THAT COULD CAUSE NEW FIRE STARTS TO SPREAD QUICKLY.
BY SATURDAY AND SATURDAY NIGHT, ADDITIONAL SHORT WAVE ACTIVITY WILL
MOVE NORTH-NORTHWESTWARD INTO THE AREA AND MOISTURE SHOULD BE
ADEQUATE FOR MOSTLY WET STORMS. WE STILL EXPECT SATURDAY TO BE THE
MOST ACTIVE DAY (AT LEAST IN TERMS OF COVERAGE OF STORMS). BY
SUNDAY, THE MODELS SUGGEST THE STRONGEST SHORT WAVE WILL MOVE
THROUGH THE AREA. BUT THE AREA OF GREATEST INSTABILITY WILL SLOWLY
SHIFT EASTWARD, SO AREAS ALONG AND EAST OF THE CASCADES WILL BE THE
AREAS THAT LIKELY SEE THE MOST COVERAGE OF STORMS. FIRE ZONES 615
AND 618 SHOULD BE IN THE CLEAR, WHILE ISOLATED STORMS MAY STILL FORM
INLAND OVER THE WEST SIDE. IT WILL BE A CLOSE CALL FOR FIRE ZONE
619.
THE RIDGE AXIS SHIFTS EAST MONDAY AS THE UPPER TROUGH AXIS MOVES
THROUGH AND THUNDERSTORM THREAT SHOULD BE MOSTLY CONFINED TO
PORTIONS OF FIRE ZONES 624 AND 625. SPILDE
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...RED FLAG WARNING FROM 5 PM THIS AFTERNOON TO 11 PM PDT SUNDAY
FOR ORZ615>625.
HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 5 AM PDT SUNDAY FOR
ORZ023.
HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 5 AM PDT SUNDAY FOR
ORZ024-026.
CA...RED FLAG WARNING FROM 5 PM THIS AFTERNOON TO 11 PM PDT SUNDAY
FOR CAZ280-281-284-285.
HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 5 AM PDT SUNDAY FOR
CAZ080-081.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL
11 PM PDT THIS EVENING FOR PZZ356-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 AM PDT SATURDAY
FOR PZZ350-356.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 PM PDT THIS EVENING FOR
PZZ350-370.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 AM PDT SATURDAY
FOR PZZ370-376.
GALE WARNING UNTIL 11 PM PDT THIS EVENING FOR PZZ376.
HAZARDOUS SEAS WARNING UNTIL 11 PM PDT THIS EVENING FOR PZZ376.
$$
DW/MAS
AREA FORECAST DISCUSSION...UPDATED
NWS MEDFORD OR
501 AM PDT FRI JUN 26 2015
.DISCUSSION...A HOT AND UNSTABLE AIR MASS WILL PERSIST OVER THE
REGION DURING THE NEXT WEEK. LOW PRESSURE OFFSHORE FROM CALIFORNIA
AND HIGH PRESSURE CENTERED IN THE GREAT BASIN ARE THE MAIN UPPER
LEVEL FEATURES AFFECTING OUR WEATHER IN THE SHORT TERM WITH THAT
STRONG RIDGING LIKELY TO PERSIST THROUGH THE WEEK.
TODAY AND SATURDAY WILL BE THE HOTTEST DAYS WITH RECORD HIGHS
LIKELY TO BE SET. BUT, AT LEAST THE FOLLOWING FIVE DAYS WILL NOT
BE THAT MUCH COOLER. THE FORECAST HAS BEEN CONSISTENT IN EXPECTING
VALLEY HIGHS DURING THE NEXT TWO DAYS OF 95 TO 110 DEGREES ON THE
WEST SIDE OF THE CASCADES THIS AFTERNOON AND 92 TO 102 ON THE EAST
SIDE.
THE OTHER MAIN FOCUS OF THE FORECAST IS THE DEVELOPMENT OF
THUNDERSTORMS WITH THE POTENTIAL FOR LIGHTNING TO CAUSE NEW FIRES.
ATMOSPHERIC MOISTURE LEVELS WILL GRADUALLY INCREASE WITH
PRECIPITABLE WATER AMOUNTS THAT WERE AT 0.50 TO 0.75 INCHES
YESTERDAY TO RISE TO 0.75 TO 1.00 INCHES TODAY. THE LEAST AMOUNT
OF RAINFALL WITH THUNDERSTORMS WILL BE IN THOSE THAT DEVELOP SOUTH
AND EAST OF SOUTHWEST OREGON. AN EARLY AFTERNOON THUNDERSTORM
CANNOT BE COMPLETELY RULED OUT, BUT THERE IS GOOD MODEL AGREEMENT
BETWEEN THE NAM AND THE SREF AND RAP SHORT TERM MODELS THAT THE
FIRST THUNDERSTORMS WILL DEVELOP AROUND 3 PM OVER THE HIGHER
TERRAIN FROM WESTERN SISKIYOU COUNTY TO THE SISKIYOU MOUNTAINS AND
CASCADES EASTWARD. COVERAGE OF STORMS WILL INCREASE DURING THE
EVENING WITH A PRIMARY FOCUS FOR NORTHWARD MOVING THUNDERSTORMS
FROM THE FOOTHILLS OF THE CASCADES (IN EASTERN PORTIONS OF JACKSON
AND DOUGLAS COUNTIES) EASTWARD. THAT WILL NOT BE THE EXCLUSIVE
LOCATION OF THUNDERSTORMS, JUST THE LIKELY FOCUS. THESE STORMS
WILL BE MOVING AT 10 TO 15 KNOTS. EMBEDDED SHORTWAVES IN THE
SOUTHERLY FLOW ALOFT ARE EXPECTED TO KEEP THUNDERSTORMS GOING
OVERNIGHT INTO SATURDAY MORNING WITH THE HIGHEST PROBABILITY ALONG
THE CASCADES. THERE IS UNCERTAINTY IN THE TRACK AND STRENGTH OF
SHORTWAVES AS THE GFS HAS A FOCUS DURING THE EVENING HOURS BEFORE
LIFTING THE MAJORITY OF ACTIVITY INTO NORTHERN OREGON WHILE THE
NAM SOLUTION WOULD ACTUALLY INCREASE THE NUMBER OF THUNDERSTORMS
IN OUR AREA DURING THE OVERNIGHT HOURS WHILE SPREADING THEM IN A
SOUTHEAST RATHER THAN SOUTH FLOW ALOFT TO THE COAST AND COASTAL
WATERS.
THUNDERSTORMS ON SATURDAY WILL PRODUCE MORE RAINFALL BUT THEY WILL
ALSO BE FASTER MOVING AT 15 TO 25 KNOTS. THUNDERSTORM COVERAGE IS
EXPECTED TO BE AT ITS PEAK DURING SATURDAY AFTERNOON AND EVENING.
THE PERSISTENT PATTERN WILL ONCE AGAIN PRODUCE NOCTURNAL
THUNDERSTORMS SATURDAY NIGHT INTO SUNDAY MORNING.
THERE IS UNCERTAINTY IN THE TIMING AND TRACK OF THE OFFSHORE LOW.
THE NAM IS FASTER THAN THE GFS BUT BOTH HAVE IT MOVING NORTH TO
THE SOUTHERN OREGON COAST ON SUNDAY. THIS WILL BRING IN SLIGHTLY
COOLER AIR AND EVENTUALLY KICK THE CONVECTIVE ACTIVITY TO THE
EAST WITH WEST SIDE OF THE CASCADES FOCUS OF THUNDERSTORMS ON
SUNDAY MORNING SHIFTING TO THE EAST SIDE FOR SUNDAY EVENING INTO
MONDAY. THUNDERSTORMS ON SUNDAY WILL HAVE A HIGHER PROBABILITY OF
PRODUCING SEVERE WIND GUSTS. THE TROUGH WITH A MUCH DRIER AIR
MASS WILL BE IN PLACE OVER THE PACIFIC NORTHWEST ON MONDAY. THUS,
A SLIGHT CHANCE OF THUNDERSTORMS WILL BE NEARLY LIMITED TO ONLY
LAKE AND MODOC COUNTIES. MONDAY NIGHT SHOULD TRANSPIRE WITHOUT
THUNDERSTORMS.
RIDGING FROM THE GREAT BASIN IS EXPECTED TO REBUILD INTO OUR AREA
TUESDAY FOR THE START OF ANOTHER WARMING TREND INTO THURSDAY.
THIS WILL ALSO SEND HIGHER AMOUNTS OF MOISTURE INTO THE EAST SIDE
ON TUESDAY THAT WILL EXPAND FARTHER WEST...TO THE WEST SIDE ON
WEDNESDAY FOR ANOTHER EPISODE OF A SLIGHT CHANCE OF AFTERNOON AND
EVENING THUNDERSTORMS. THE PROBABILITY WILL BE THE LOWEST FOR THE
COAST AND DOUGLAS COUNTY.
FORECAST UNCERTAINTY INCREASES BEYOND WEDNESDAY AS THE ECMWF MODEL
INDICATES A STRONG TROUGH MOVING INTO THE PACIFIC NORTHWEST WILL
FINALLY CHANGE THE PATTERN AND BRING SOME COOLING FOR THE END OF
THE WEEK, BUT THE GFS IS PERSISTENT AND LEAVES THE HOT GREAT
BASIN RIDGE IN COMMAND. FOR NOW, WE WILL LEAN TOWARD PERSISTENCE.
&&
.AVIATION...FOR THE 26/12Z TAF CYCLE...LOW CLOUDS WILL CONTINUE
ALONG THE NORTH COAST WITH IFR TO LIFR CIGS THIS MORNING GRADUALLY
RISING TO MVFR THIS AFTERNOON. ELSEWHERE VFR CONDITIONS WILL
PREVAIL.
LATE THIS AFTERNOON INTO THE EVENING ISOLATED THUNDERSTORMS ARE
EXPECTED ALONG AND NEAR THE OREGON CASCADES...THE UPPER KLAMATH
BASIN...AND WESTERN SISKIYOU COUNTY. THE BEST CHANCE OF
THUNDERSTORMS IS IN THE 00-06Z TIME FRAME FOR THIS TAF CYCLE AT KLMT
AND KRBG. THESE STORMS ARE EXPECTED TO BE HIGH-BASED, DRY, AND
THEREFORE COULD CONTAIN GUSTY OUTFLOW WINDS AND POSSIBLY ISOLATED
MICROBURSTS. BTL/SPILDE
&&
.MARINE...UPDATED 300 AM PDT FRIDAY 26 JUNE 2015...A THERMAL TROUGH
WILL BRING GALE FORCE NORTH WINDS SOUTH OF CAPE BLANCO TODAY WITH
VERY STEEP WIND WAVE DOMINATED SEAS. THE THERMAL TROUGH WILL WEAKEN
AND BOTH WINDS AND SEAS ARE EXPECTED TO LOWER THIS WEEKEND.
THUNDERSTORMS ARE POSSIBLE TONIGHT INTO SATURDAY MORNING. THE
THERMAL TROUGH WILL THEN STRENGTHEN AGAIN MONDAY AND TUESDAY WITH
CONDITIONS AT LEAST HAZARDOUS TO SMALL CRAFT. STRONGEST
WINDS AND SEAS WILL AGAIN BE SOUTH OF CAPE BLANCO. SPILDE
&&
.FIRE WEATHER...UPDATED 400 AM PDT FRIDAY 26 JUNE 2015...HAVE MADE
NO CHANGES WITH RESPECT TO THE RED FLAG WARNING (RFWMFR) HEADLINES
IN PLACE ACROSS THE AREA BEGINNING LATER THIS AFTERNOON. MODELS
CONTINUE TO SHOW MOISTURE INCREASING IN THE SOUTH TO SOUTHEAST FLOW
DEVELOPING ALOFT IN A CORRIDOR BETWEEN AN UPPER LOW OFFSHORE AND THE
MID LEVEL RIDGE CENTERED OVER THE GREAT BASIN. THIS IS A FAVORABLE
THUNDERSTORM PATTERN AND THIS CORRIDOR IS AIMED RIGHT OVER SW
OREGON/NORCAL, WHERE ISOLATED TO SCATTERED THUNDERSTORMS ARE
EXPECTED TO DEVELOP LATER THIS AFTERNOON AND EVENING. THIS PATTERN
WILL PERSIST FRIDAY NIGHT THROUGH MUCH OF THE WEEKEND AS THE UPPER
LOW SLOWLY MOVES NORTHWARD ALONG THE CALIFORNIA COAST.
CONFIDENCE ON THE EXACT LOCATION OF STORMS REMAINS FAIRLY LOW AS MID
AND UPPER LEVEL SUPPORT FOR STORMS (SHORTWAVES) IS WEAK, BUT WITH
STRONG HEATING AND THE RESULTING INSTABILITY OVER ABNORMALLY DRY
FUELS ACROSS A LARGE PART OF THE AREA (NEAR-RECORD DRYNESS ALONG THE
COAST)...THE THREAT FOR ABUNDANT LIGHTNING IS A BIG CONCERN FOR
INITIAL ATTACK. STORMS SHOULD INITIATE OVER THE HIGHER TERRAIN THIS
AFTERNOON, THEN PROPAGATE NORTHWESTWARD WITH TIME THIS EVENING AND
OVERNIGHT. A STRONG MOISTURE GRADIENT WILL EXIST ALONG THE CASCADES.
STORMS OVER THE EAST SIDE SHOULD BE FAIRLY DRY, WHERE PWS ARE
GENERALLY LESS THAN 0.75 OF AN INCH. PWS OF 1.00-1.25 INCHES EXIST
ALONG AND WEST OF THE CASCADES WHERE STORMS THAT DEVELOP SHOULD BE
COMPARABLY WETTER. ANY STORMS WILL HAVE THE ABILITY TO PRODUCE GUSTY
OUTFLOWS THAT COULD CAUSE NEW FIRE STARTS TO SPREAD QUICKLY.
BY SATURDAY AND SATURDAY NIGHT, ADDITIONAL SHORT WAVE ACTIVITY WILL
MOVE NORTH-NORTHWESTWARD INTO THE AREA AND MOISTURE SHOULD BE
ADEQUATE FOR MOSTLY WET STORMS. WE STILL EXPECT SATURDAY TO BE THE
MOST ACTIVE DAY (AT LEAST IN TERMS OF COVERAGE OF STORMS). BY
SUNDAY, THE MODELS SUGGEST THE STRONGEST SHORT WAVE WILL MOVE
THROUGH THE AREA. BUT THE AREA OF GREATEST INSTABILITY WILL SLOWLY
SHIFT EASTWARD, SO AREAS ALONG AND EAST OF THE CASCADES WILL BE THE
AREAS THAT LIKELY SEE THE MOST COVERAGE OF STORMS. FIRE ZONES 615
AND 618 SHOULD BE IN THE CLEAR, WHILE ISOLATED STORMS MAY STILL FORM
INLAND OVER THE WEST SIDE. IT WILL BE A CLOSE CALL FOR FIRE ZONE
619.
THE RIDGE AXIS SHIFTS EAST MONDAY AS THE UPPER TROUGH AXIS MOVES
THROUGH AND THUNDERSTORM THREAT SHOULD BE MOSTLY CONFINED TO
PORTIONS OF FIRE ZONES 624 AND 625. SPILDE
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...RED FLAG WARNING FROM 5 PM THIS AFTERNOON TO 11 PM PDT SUNDAY
FOR ORZ615>625.
HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 5 AM PDT SUNDAY FOR
ORZ023.
HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 5 AM PDT SUNDAY FOR
ORZ024-026.
CA...RED FLAG WARNING FROM 5 PM THIS AFTERNOON TO 11 PM PDT SUNDAY
FOR CAZ280-281-284-285.
HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 5 AM PDT SUNDAY FOR
CAZ080-081.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL
11 PM PDT THIS EVENING FOR PZZ356-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 AM PDT SATURDAY
FOR PZZ350-356.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 PM PDT THIS EVENING FOR
PZZ350-370.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 AM PDT SATURDAY
FOR PZZ370-376.
GALE WARNING UNTIL 11 PM PDT THIS EVENING FOR PZZ376.
HAZARDOUS SEAS WARNING UNTIL 11 PM PDT THIS EVENING FOR PZZ376.
$$
DW/MAS
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1035 AM EDT FRI JUN 26 2015
.SYNOPSIS...
HIGH PRESSURE WILL WEAKEN ACROSS THE SOUTHEAST TODAY AS A COLD FRONT
APPROACHES. THE COLD FRONT MOVES THROUGH SATURDAY...MOVING EAST OF
THE REGION BY SUNDAY. A WEAK FRONT WILL APPROACH BY MID WEEK AND
LINGER NEAR THE REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
1030 AM EDT UPDATE...AREA IS CLEAR OF RADAR ACTIVITY AT THE
MOMENT...WITH AT LEAST SOME ACTIVITY EXPECTED LATER THIS AFTERNOON.
LATEST HRRR HAS SOME CONVECTION AFTER 19Z. SHEAR IS BETTER TO THE
NORTH IN THE BLUE RIDGE MOUNTAINS...WITH A CONSEQUENT INCREASE IN
THE POSSIBILITY FOR SEVERE WEATHER. TWEAKED
TEMPERATURES...SKY...AND POP TO ACCOUNT FOR LATEST OBSERVATIONS AND
HRRR EXPECTATIONS.
AS OF 6 AM...AIDED BY ENCROACHING OUTFLOW BOUNDARIES...A FEW SHOWERS
SHOULD PERCOLATE ALONG THE TENN BORDER COUNTIES BEFORE ASHING OUT
LATER THIS MORNING. OTHERWISE...VARYING DEGREES OF HIGH LVL DEBRIS
CLOUDS WILL GIVE WAY TO DEVELOPING CU.
THERE REMAINS THE POSSIBILITY OF DEEP CONVECTIVE REMNANTS FROM KY
MCS ACTIVITY REACHING THE NC MTNS BY DAYBREAK BEFORE ASHING OUT
COMPLETELY BY MID-MORNING. WILL CONTINUE TO MONITOR CONVECTION
ALLOWING MODELS AND UPSTREAM TRENDS. EXPECTING AN UPTICK IN FORCING
AND FLOW AS THE AFTERNOON AND EVENING WEARS ON AS S/WV ENERGY
ENCROACHES THE SE CONUS AND UPPER HEIGHTS STEADILY FALL. GIVEN
THIS...TSTM CVRG MAY WIND UP BECOMING NUMEROUS AND POSSIBLY SVR
THIS AFTERNOON GIVEN FORECAST SNDGS DEPICTING MODERATE
INSTABILITY...DECENTLY STEEP LAPSE RATES AND FAVORABLE DELTA THETA-E
VALUES. WILL FORECAST ONE MORE HOT DAY TODAY...CLOSE TO PERSISTENCE
AND FEATURING WIDESPREAD MIDDLE AND UPPER 90S ACRS THE PIEDMONT.
IMPULSES WITHIN THE QUICKENING SW FLOW MAY BE ABLE TO SUSTAIN SOME
DEGREE OF TSTM ACTIVITY WELL PAST SUNSET...WILL WILL KEEP AT LEAST A
TOKEN CHANCE POP INTO THE OVERNIGHT HOURS.
&&
.SHORT TERM /SATURDAY/...
AT 230 AM EDT FRIDAY...ON SATURDAY MORNING AN UPPER TROUGH WILL BE
OVER THE EASTER USA...WHILE A RIDGE WILL BE OVER THE WEST. THIS
PATTERN AMPLIFIES INTO SUNDAY...WHILE A CLOSED UPPER LOW CROSSES THE
LOWER GREAT LAKES. A WEAKER OPEN UPPER LOW CROSSES THE UPPER GREAT
LAKES ON SUNDAY NIGHT.
AT THE SURFACE...A ROBUST COLD WILL APPROACH FORM THE WEST ON ON
SATURDAY...CROSSING THE AREA IN THE EARLY EVENING. WHILE CAPE MAY BE
SOMEWHAT MODEST...SHEAR WILL BE PRESENT...AND ORGANIZED CONVECTION
CANNOT BE RULED OUT. COOLER AND DRIER AIR WILL MOVE IN BEHIND THE
FRONT FROM SATURDAY NIGHT THROUGH SUNDAY NIGHT. TEMPERATURES WILL
RUN BELOW NORMAL.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
AT 230 AM EDT FRIDAY...ON MONDAY AN ANOMALOUS HIGH AMPLITUDE UPPER
ROUGH WILL EXTENDING ROM HUDSON BAY TO THE GULF OF MEXICO...WHILE AN
UPPER RIDGE WILL BE OVER THE WESTERN USA AND WESTER CANADA. THIS
PATTER PERSISTS INTO TUESDAY...THEN DEAMPLIFIES ON WEDNESDAY. ON
THURSDAY THE UPPER TROUGH REAMPLIFIES SOMEWHAT...WHILE THE RIDGE TO
THE WEST REMAINS RATHER FLAT.
AT THE SURFACE...A SURFACE RIDGE WILL BE OVER THE SOUTHERN
APPALACHIANS ON MONDAY...IN THE WAKE OF A DEPARTING COLD FRONT. THE
TRAILING PORTION OF THE FRONT LIFTS NORTH ACROSS OUR AREA AS A WARM
FRONT BY EARLY TUESDAY. ANOTHER COLD FRONT DROPS SOUTHEAST ACROSS
OUR AREA ON WEDNESDAY...STALLING NEAR THE NC AND SC BORDER BY
THURSDAY. A WEAK CAPPING INVERSION ALOFT MAY KEEP OUR AREA SOMEWHAT
STABLE ON MONDAY...BUT WITH FRONTS MOVING TROUGH THE AREA AND
INSTABILITY INCREASING...THE REST OF THE WEEK SHOULD BE INCREASINGLY
MORE ACTIVE. TEMPERATURES WILL RUN NEAR NORMAL.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
AT KCLT...JUST VARYING DEGREES OF HIGH LVL DEBRIS CLOUDS AND A LIGHT
WIND TENDING TO THE NORTH THIS MORNING EXPECTED FOR THIS MORNING.
WINDS WILL BECOME SW 6-8 KTS THIS AFTERNOON AND TSTM CHANCES WILL
INCREASE...ESPECIALLY AFTER 20Z. THE THREAT FOR TSTMS REDEVELOPING
AND MOVING ACRS THE NC PIEDMONT WILL LINGER THROUGH LATE EVENING.
ELSEWHERE...JUST A FEW SHOWERS ACRS THE WESTERN NC MTNS THIS MORNING
WITH THE TSTM CVRG STEADILY INCREASING THIS AFTERNOON...A PROB30
GROUP WILL BE CARRIED FOR ALL TERMINAL LOCATIONS. TSTM CHANCES
SHOULD LINGER THROUGH AT LEAST LATE EVENING WITH AT LEAST SMALL
SHOWER CHANCES CONTINUING OVERNIGHT. GETTING MIXED SIGNALS WITH
RESPECT TO SATURDAY MORNING FLIGHT RESTRICTION CVRG...BUT THE SREF
LIMITS THE BEST CHANCES TO THE UPSLOPE AREAS OF THE SOUTHERN
MOUNTAINS.
OUTLOOK...A COLD FRONT WILL APPROACH FROM THE NW AND PASS THRU
ON SATURDAY. MORNING RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE
POSSIBLE...PARTICULARLY WHERE HEAVY RAIN FALLS LATER TODAY...AND IN
THE MOUNTAIN RIVER VALLEYS. BEHIND THE COLD FRONT...A MUCH DRIER AND
COOLER AIRMASS WILL OVERSPREAD THE REGION FOR EARLY NEXT WEEK...WITH
A SECOND COLD FRONT POSSIBLY ARRIVING BY MID-WEEK.
CONFIDENCE TABLE...
14-20Z 20-02Z 02-08Z 08-12Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 97%
KAVL HIGH 100% HIGH 100% HIGH 100% MED 68%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 87%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JAT
NEAR TERM...CSH/WJM
SHORT TERM...JAT
LONG TERM...JAT
AVIATION...CSH
AREA FORECAST DISCUSSION
NWS ALBANY NY
447 PM EDT FRI JUN 26 2015
.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVER THE REGION THIS EVENING...RESULTING IN
A BRIEF PERIOD OF FAIR AND DRY WEATHER. AN INTENSIFYING STORM OVER
THE OHIO VALLEY WILL APPROACH ON SATURDAY...BRINGING PERIODS OF RAIN
AND COOL CONDITIONS FOR THIS FIRST FULL WEEKEND OF SUMMER.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
COMING SOON...
AS OF 130 PM EDT...THIS UPDATE IS TO MAKE MINOR ADJUSTMENTS TO THE
POP...WX...SKY COVER...HOURLY TEMPS AND MAX TEMP GRIGDS FOR THIS
AFTERNOON.
PREVIOUS DISCUSSION...
THE COLD FRONT HAS SLIPPED SOUTH OF THE REGION WITH THE MAIN
FEATURE OF INTEREST THE UPPER LEVEL TROUGH AXIS MOVING TOWARDS THE
ST LAWRENCE RIVER VALLEY PER THE LATEST HRRR/RAP40/NAM. PARTLY
CLOUDY/MOSTLY CLEAR CONDITIONS WILL BECOME MOSTLY CLOUDY FROM THE
CAPITAL REGION/MOHAWK VALLEY SOUTH WITH THE UPPER TROUGH PASSAGE
THIS AFTERNOON. SOME ISOLD SHOWERS ARE POSSIBLE DUE TO THE
CYCLONIC VORTICITY ADVECTION DUE TO THE SHORT- WAVE ROTATING
AROUND THE UPPER LOW. SOME SCT SHOWERS ARE POSSIBLE OVER THE
HIGHER TERRAIN. ANY RAINFALL AMOUNTS SHOULD BE LIGHT WITH A FEW
HUNDREDTHS. THE LATEST HRRR INDICATES THE SHOWER SHOULD DIMINISH
NORTH OF THE CAPITAL REGION/MOHAWK VALLEY IN THE EARLY PM.
HIGHS MOSTLY 70 TO 80 WITH SOME UPPER 60S OVER THE HIGHER TERRAIN.
INTO TONIGHT...SURFACE HIGH BUILDS AND CRESTS ACROSS THE REGION
FOR A TRANQUIL PERIOD OF WEATHER. A LIGHT NORTHERLY WIND WILL
SUBSIDE TO LIGHT AND VARIABLE UNDER PTCLOUDY-MOCLEAR SKIES.
HOWEVER...THE METEOROLOGICAL EYES WILL BE WATCHING WHAT TRANSPIRES
UPSTREAM AS NCEP MODEL SUITE AND INTERNATIONAL GUIDANCE ARE
BECOMING MORE IN AGREEMENT WITH AN ANOMALOUS DIGGING/PHASING
TROUGH ACROSS THE MID WEST WITH EXPANDING AREA OF CLOUDS AND
RAIN/SHOWERS. CLOUD COVERAGE MAY APPROACHING OUR SOUTHERN MOST
ZONES OVERNIGHT BUT IT WILL REMAIN DRY. OVERNIGHT LOWS MAINLY INTO
THE 50S WITH SOME UPPER 40S ACROSS PORTIONS OF THE
DACKS...BERKS...SOUTHERN GREENS.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
COMING SOON...
IMPRESSIVE STORM TO DEVELOP ACROSS THE OHIO VALLEY AND IMPACT
OUR REGION THIS WEEKEND...
THE PREVIOUS EXCELLENT AFD FOLLOWS WITH MINOR UPDATES PER THE 00Z
GUIDANCE.
SATURDAY...THE 26/00Z ECMWF SHOWS THE SFC WAVE MOVING A LITTLE
SLOWER TOWARDS A MID LEVEL JET CONFLUENT REGION OVER E-OH AND W-PA
BY MID MORNING. THE ISENTROPIC LIFT INCREASES QUICKLY ON THE
290-300K SFC BY THE LATE MORNING INTO THE AFTERNOON ESPECIALLY
SOUTH AND WEST OF THE CAPITAL REGION. THE LOW-LEVEL BAROCLINIC
LEAFLET STRENGTHENS BETWEEN THE RETREATING AND STRENGTHENING HIGH
OFF THE NEW ENGLAND COAST /1022MB/ ...AND THE LOW PRESSURE SYSTEM
MOVING TOWARDS LAKE ERIE AND WRN PA BY THE EARLY PM WITH SUB
1000MB EXPECTED. THE GFS/ECMWF ATTEMPT TO HAVE A SECONDARY LOW
FORM OVER THE MID ATLANTIC REGION THROUGH THE AFTERNOON. OVER
RUNNING RAINFALL AHEAD OF THE PRIMARY SFC CYCLONE...AND THE WARM
FRONT SHOULD OVER SPREAD THE REGION BY THE EARLY EVENING. AN
ANOMALOUS H850/925 E/SE LLJ INCREASES AHEAD OF THE SFC WAVE TO
BETTER THAN 40KTS. THE LATEST GFS/ECMWF HAVE E/SE WINDS OF 45-55KTS
OVER THE FCST AREA BY 8 PM SAT. PLENTY OF ATLANTIC MOISTURE
ENTRAINMENT SHOULD BE ADVECTED INTO THE REGION FOR PERIODS OF
MDT-HVY RAIN BY SAT EVENING. HIGHS WILL BE BELOW NORMAL WITH MID
AND U60S COMMON IN THE LOWER ELEVATIONS AND M50S TO L60S OVER THE
HIGHER TERRAIN ACROSS THE CATSKILLS.
SATURDAY NIGHT...THIS WILL BE THE HIGHEST POTENTIAL IMPACT
PERIOD...AND WILL CONTINUE WHAT THE PREVIOUS SHIFT HIGHLIGHTED IN
THE SEGMENTED HWO. THE GEFS INDICATE ANOMALOUS LLJ WITH U-WIND
ANOMALIES 3 TO 5 STANDARD DEVIATIONS GREATER THAN NORMAL /STRONG
EASTERLIES/ AND STRONG V-WIND ANOMALIES /STRONG SOUTHERLIES/ 3 TO
5 STANDARD DEVIATIONS GREATER THAN NORMAL. HENCE...A SE LOW-LEVEL
JET MAX WILL FOCUS PERIODS OF MODERATE TO HEAVY RAINFALL. THE E/SE
FLOW WILL ENHANCE THE RAINFALL ALONG THE SPINE OF THE ERN
DACKS...ERN CATSKILLS...SRN GREENS..BERKS...AND NORTHERN LITCHFIELD
HILLS. PWATS LOOK TO BE 1 TO 2 STD DEVS ABOVE NORMAL...SLIGHTLY
HIGHER SOUTH AND EAST OF THE CAPITAL DISTRICT WHERE UP TO 3 STD IS
CURRENT PROGGED. THERE IS A SMALL WINDOW WHERE THE E/SE WINDS MAY
GUST CLOSE TO WIND ADVISORY LEVELS OVER THE SRN GREENS IN SRN
VT...NRN TACONICS...AND POSSIBLY THE NRN BERKS. IT WILL DEPEND ON
HOW MUCH MOMENTUM CAN BE TRANSFERRED TO SFC THROUGH A STRONG
INVERSION IN THE SOUNDINGS AND ITS OCCURRING NOCTURNALLY. WE WILL
MENTION THE THREAT AND CONTINUE WHAT THE DAY SHIFT HAS IN THE
HWO. IT IS HARD TO TELL HOW MUCH OF A THREAT THE RAIN WILL HAVE
FOR FLOODING AT THIS TIME. 1 TO 3 INCHES LOOKS POSSIBLE SAT PM
INTO SUNDAY MORNING BASED ON THE EC/WPC/CAN GGEM GUIDANCE...WITH
THE MESOSCALE MODELS SHOWING SOME 3-4 INCH AMOUNTS IN THE ERN
CATSKILLS...AND ERN DACKS. PER EXTENSIVE COLLABORATION FROM
SURROUNDING WFOS...CONFIDENCE REMAINS LOW FOR A FLOOD WATCH
AT THIS TIME...BUT WILL CONTINUE TO MONITOR AND MENTION IN THE
HWO. ZONE FFG VALUES REMAIN HIGH IN THE 3/6-HR TIME FRAME.
CATEGORICAL POPS WERE CONTINUED WITH RAIN...HVY AT
TIMES...SATURDAY NIGHT. IN ADDITION...SHOWALTER VALUES ARE PROGGED
EVEN LOWER WITH SUB ZERO VALUES ADVECTING INTO THE REGION TO
WARRANT AN INCLUSION OF THUNDERSTORMS OVERNIGHT. LOWS WILL BE
MAINLY IN THE 50S.
SUNDAY...MODEL TRENDS NOW WANT TO ADVECT IN A DRY SLOT DURING THE
DAY WHICH WILL REDUCE THE PRECIP COVERAGE AND INTENSITY ACROSS
MOST OF THE REGION FOR A SMALL WINDOW OF TIME. QUESTION IS IF WE
ARE ABLE TO SEE SOME INSOLATION TO ASSIST WITH DESTABILIZATION.
WHILE THE MAIN THRUST OF ADVECTION WILL BE WELL TO OUR NORTH...THE
VERTICALLY STACKED LOW ACROSS WESTERN NY WITH SECONDARY LOW
POSSIBLY TRACKING NORTH...NARROW LINES OF CONVECTION COULD EVOLVE.
WE WILL FOLLOW A BLENDED MOS VALUES WHICH REQUIRES A SLIGHT
ADJUSTMENT UPWARD IN THE AFTERNOON HIGH TEMPS TO LOWER HALF OF THE
70S FOR VALLEY LOCATIONS AND 60S ELSEWHERE.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
THE EXTENDED FORECAST BEGINS WITH A BRIEF PERIOD OF DRY WEATHER...AS
A SHORT-WAVE RIDGE BUILDS IN OVER NY AND NEW ENGLAND ON MONDAY.
SOME ISOLD-SCT INSTABILITY SHOWERS /AS THE COLD POOL ALOFT DRIFTS
OVER NEW ENGLAND AND SE QUEBEC/ ARE POSSIBLE DURING THE AFTERNOON
NORTH OF THE CAPITAL REGION/MOHAWK VALLEY ESPECIALLY OVER THE SRN
DACKS...AND SRN GREENS. MOST OF THE FCST AREA SHOULD BE DRY...WITH
MORE SUNSHINE FROM THE CAPITAL REGION SOUTH. TEMPS WILL STILL RUN A
LITTLE BELOW NORMAL WITH H850 TEMPS IN THE +10C TO +12C RANGE DURING
THE AFTERNOON. MAX TEMPS WILL BE IN THE M60S TO L70S OVER THE HILLS
AND MTNS...AND MAINLY LOWER TO M70S IN THE VALLEYS /A FEW U70S IN
THE MID HUDSON VALLEY/. CLOUDS BEGIN TO INCREASE FROM THE WEST
MONDAY NIGHT...AS THE NEXT UPPER LEVEL TROUGH MOVES TOWARDS NY AND
NEW ENGLAND. SOME WARM ADVECTION SHOWERS MAY GET CLOSE TO LOCATIONS
WEST OF THE HUDSON RIVER VALLEY BTWN 06Z-12Z. LOWS WILL BE MAINLY
IN THE 50S WITH A FEW LOWER 60S IN THE MID HUDSON VALLEY/NW CT.
TUE-TUE NIGHT...A POTENTIAL ACTIVE WEATHER DAY...AS A WARM FRONT OR
PREFRONTAL SFC TROUGH BASED ON THE GEFS/GFS/ECMWF IMPACTS THE FCST
AREA WITH SHOWERS AND THUNDERSTORMS. THE SHORT-WAVE PIVOTING
THROUGH THE NEUTRAL-NEGATIVELY TILTED LONG-WAVE TROUGH WILL ALSO
HELP ENHANCE THE LIFT FOR THE SHOWERS AND THUNDERSTORMS. THE GFS
CONTINUES TO HAVE SFC DEWPTS IN THE 60S WITH SOME L70S. NOT SURE
ABOUT L70S THIS FAR OUT...BUT SBCAPES IN THE 1000-2000 J/KG RANGE
ARE NOT OUT OF THE QUESTION...IF SUFFICIENT SFC
DESTABILIZATION/HEATING OCCURS. THE GFS FOR TUE CONTINUES TO HAVE 0-
6 KM BULK SHEAR VALUES OF 35-40 KTS INDICATIVE OF SOME DEEP
ORGANIZED CONVECTION. SOME STRONGER STORMS WILL BE POSSIBLE IN THE
PM INTO THE EARLY EVENING...ESPECIALLY IF THERE IS ENOUGH SUNSHINE.
THE GEFS HAVE PWATS RISE ABOUT 1-2 STANDARD DEVIATIONS ABOVE
NORMAL...AS SOME LOCALLY HEAVY RAINFALL WILL BE POSSIBLE. IT WILL BE
MORE HUMID WITH HIGHS IN THE 70S TO L80S. THE SHOWERS AND
THUNDERSTORMS SHOULD DIMINISH OVERNIGHT WITH LOWS IN THE U50S TO
L60S.
WEDNESDAY-WEDNESDAY NIGHT...THE UPPER LEVEL TROUGH CONTINUES TO BE
OVER SE CANADA AND THE NORTHEAST WITH BROAD CYCLONIC FLOW. THE
FIRST COLD FRONT SHOULD PASS SOUTH OF THE REGION EARLY IN THE DAY.
ANOTHER SFC TROUGH OR SECONDARY COLD FRONT MAY MOVE THROUGH IN THE
CYCLONIC FLOW FOR SCT SHOWERS AND ISOLD THUNDERSTORMS. HIGHS WILL
BE IN THE U60S TO L70S OVER THE MTNS...AND MAINLY MID AND U70S OVER
THE HILLS AND VALLEY LOCATIONS. THE MEDIUM RANGE GUIDANCE HAS
TRENDED DRIER WED NIGHT WITH HIGH PRESSURE RIDGING IN FROM THE GREAT
LAKES REGION. COOLER AND DRIER CONDITIONS WILL RETURN WITH LOWS IN
THE 50S.
THURSDAY INTO FRIDAY...TEMPERED THE POPS DOWN FURTHER THURSDAY TO
NOTHING OR SLIGHT CHC...AS THE ECMWF/GFS INDICATES A BRIEF PERIOD OF
DRY WX WITH THE UPPER TROUGH AXIS MOVING DOWNSTREAM OF ERN NY AND
WRN NEW ENGLAND...AND A SFC RIDGE MOVING IN OVER THE REGION IN THE
QUASI-ZONAL FLOW UPSTREAM. LOWS PRESSURE MAY MOVE NORTHEAST FROM
THE MID ATLANTIC REGION THU NIGHT INTO FRIDAY WITH INCREASING
CHANCES OF SHOWERS FROM SOUTH TO NORTH. TEMPS STILL LOOK A LITTLE
BELOW NORMAL TO CLOSE THE EXTENDED.
&&
.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
VFR CONDITIONS THROUGH THE FIRST 24 HOURS...EXCEPT PERHAPS MVFR
LAST COUPLE OF HOURS AT KPOU AS -RA MOVES IN TO LOWER VSBYS...PART
OF LOW PRESSURE DEEPENING OVER THE OHIO VALLEY AND HEADING EAST.
THINGS LOOK MUCH WORSE JUST BEYOND 24 HOURS...WITH MOISTURE AND
INSTABILITY INCREASING. ONLY SUB-MARGINAL SHEAR AT KPOU TOWARD 18Z
SAT. SFC WINDS SHOULD REMAIN UNDER 10 KTS AT ALL AIRPORTS.
OUTLOOK...
SATURDAY NIGHT: HIGH OPERATIONAL IMPACT. BREEZY DEFINITE RA...TSRA.
SUNDAY: HIGH OPERATIONAL IMPACT. BREEZY DEFINITE SHRA...TSRA.
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. BREEZY CHANCE OF SHRA.
MONDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
&&
.FIRE WEATHER...
MINIMAL TO LOW FIRE WEATHER RELATED CONCERNS THROUGH THE WEEKEND
AS A WIDESPREAD...SOAKING RAINFALL OCCURS ACROSS THE REGION SATURDAY
AFTERNOON INTO SUNDAY. THE RH VALUES WILL RECOVER TO BETWEEN 75
AND 100 PERCENT TONIGHT AND REMAIN HIGH THROUGH THE WEEKEND.
&&
.HYDROLOGY...
EXCEPT FOR ISOLATED SHOWERS THIS EVENING...DRY WEATHER IS EXPECTED
INTO SATURDAY MORNING BEFORE A STRONG LOW PRESSURE SYSTEM DEVELOPS
NEAR THE OHIO VALLEY AND MOVES TOWARDS THE EASTERN GREAT LAKES
REGION. PERIODS OF MODERATE TO HEAVY RAINFALL ARE POSSIBLE LATE
SATURDAY AFTERNOON INTO EARLY SUNDAY...DEPENDING ON THE EVENTUAL
TRACK AND EVOLUTION OF LOW PRESSURE DEVELOPING ACROSS THE OHIO
VALLEY REGION.
RIGHT NOW...ONE TO TWO INCHES OF RAINFALL ARE POSSIBLE ACROSS THE
HSA WITH SOME UPSLOPE AREAS GETTING A LITTLE MORE. THE TRACK AND
RAINFALL DURATION WILL DETERMINE WHERE THE HIGHER AMOUNTS WILL
OCCUR. 12Z MODEL RUNS HAVE GENERALLY DECREASED THE RAINFALL
AMOUNTS BY A QUARTER TO HALF AN INCH COMPARED TO PREVIOUS RUNS.
THE LATEST MMEFS GUIDANCE CONTINUES TO SUGGEST WITHIN BANK RISES
TO THE CAUTION OR ALERT STAGES AT ONLY A COUPLE OF SITES AT THIS
TIME.
URBAN AND SMALL STREAM CONCERNS ACROSS THE HSA WILL HAVE TO BE
MONITORED...AND WILL MENTION IN THE HWO. ALSO...IF CONFIDENCE
INCREASES FOR THE POTENTIAL OF WIDESPREAD MINOR FLOODING...THEN A
FLOOD WATCH MAY BE NEEDED FOR PORTIONS OF THE HSA LATER IN TIME.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR
WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...GJM
NEAR TERM...GJM
SHORT TERM...GJM
LONG TERM...WASULA
AVIATION...ELH
FIRE WEATHER...GJM/BGM/WASULA
HYDROLOGY...GJM/BGM/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
159 PM EDT FRI JUN 26 2015
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE REGION THIS
AFTERNOON WITH ISOLATED SHOWERS MAINLY FROM THE MOHAWK VALLEY
SOUTH AND EAST. THEREAFTER...HIGH PRESSURE WILL BUILD OVER THE
REGION LATE THIS AFTERNOON INTO THIS EVENING...RESULTING IN A
BRIEF PERIOD OF FAIR AND DRY WEATHER. AN INTENSIFYING STORM OVER
THE OHIO VALLEY WILL APPROACH ON SATURDAY...BRINGING PERIODS OF
RAIN AND COOL CONDITIONS FOR THIS FIRST FULL WEEKEND OF SUMMER.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 130 PM EDT...THIS UPDATE IS TO MAKE MINOR ADJUSTMENTS TO THE
POP...WX...SKY COVER...HOURLY TEMPS AND MAX TEMP GRIGDS FOR THIS
AFTERNOON.
PREVIOUS DISCUSSION...
THE COLD FRONT HAS SLIPPED SOUTH OF THE REGION WITH THE MAIN
FEATURE OF INTEREST THE UPPER LEVEL TROUGH AXIS MOVING TOWARDS THE
ST LAWRENCE RIVER VALLEY PER THE LATEST HRRR/RAP40/NAM. PARTLY
CLOUDY/MOSTLY CLEAR CONDITIONS WILL BECOME MOSTLY CLOUDY FROM THE
CAPITAL REGION/MOHAWK VALLEY SOUTH WITH THE UPPER TROUGH PASSAGE
THIS AFTERNOON. SOME ISOLD SHOWERS ARE POSSIBLE DUE TO THE
CYCLONIC VORTICITY ADVECTION DUE TO THE SHORT- WAVE ROTATING
AROUND THE UPPER LOW. SOME SCT SHOWERS ARE POSSIBLE OVER THE
HIGHER TERRAIN. ANY RAINFALL AMOUNTS SHOULD BE LIGHT WITH A FEW
HUNDREDTHS. THE LATEST HRRR INDICATES THE SHOWER SHOULD DIMINISH
NORTH OF THE CAPITAL REGION/MOHAWK VALLEY IN THE EARLY PM.
HIGHS MOSTLY 70 TO 80 WITH SOME UPPER 60S OVER THE HIGHER TERRAIN.
INTO TONIGHT...SURFACE HIGH BUILDS AND CRESTS ACROSS THE REGION
FOR A TRANQUIL PERIOD OF WEATHER. A LIGHT NORTHERLY WIND WILL
SUBSIDE TO LIGHT AND VARIABLE UNDER PTCLOUDY-MOCLEAR SKIES.
HOWEVER...THE METEOROLOGICAL EYES WILL BE WATCHING WHAT TRANSPIRES
UPSTREAM AS NCEP MODEL SUITE AND INTERNATIONAL GUIDANCE ARE
BECOMING MORE IN AGREEMENT WITH AN ANOMALOUS DIGGING/PHASING
TROUGH ACROSS THE MID WEST WITH EXPANDING AREA OF CLOUDS AND
RAIN/SHOWERS. CLOUD COVERAGE MAY APPROACHING OUR SOUTHERN MOST
ZONES OVERNIGHT BUT IT WILL REMAIN DRY. OVERNIGHT LOWS MAINLY INTO
THE 50S WITH SOME UPPER 40S ACROSS PORTIONS OF THE
DACKS...BERKS...SOUTHERN GREENS.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
IMPRESSIVE STORM TO DEVELOP ACROSS THE OHIO VALLEY AND IMPACT
OUR REGION THIS WEEKEND...
THE PREVIOUS EXCELLENT AFD FOLLOWS WITH MINOR UPDATES PER THE 00Z
GUIDANCE.
SATURDAY...THE 26/00Z ECMWF SHOWS THE SFC WAVE MOVING A LITTLE
SLOWER TOWARDS A MID LEVEL JET CONFLUENT REGION OVER E-OH AND W-PA
BY MID MORNING. THE ISENTROPIC LIFT INCREASES QUICKLY ON THE
290-300K SFC BY THE LATE MORNING INTO THE AFTERNOON ESPECIALLY
SOUTH AND WEST OF THE CAPITAL REGION. THE LOW-LEVEL BAROCLINIC
LEAFLET STRENGTHENS BETWEEN THE RETREATING AND STRENGTHENING HIGH
OFF THE NEW ENGLAND COAST /1022MB/ ...AND THE LOW PRESSURE SYSTEM
MOVING TOWARDS LAKE ERIE AND WRN PA BY THE EARLY PM WITH SUB
1000MB EXPECTED. THE GFS/ECMWF ATTEMPT TO HAVE A SECONDARY LOW
FORM OVER THE MID ATLANTIC REGION THROUGH THE AFTERNOON. OVER
RUNNING RAINFALL AHEAD OF THE PRIMARY SFC CYCLONE...AND THE WARM
FRONT SHOULD OVER SPREAD THE REGION BY THE EARLY EVENING. AN
ANOMALOUS H850/925 E/SE LLJ INCREASES AHEAD OF THE SFC WAVE TO
BETTER THAN 40KTS. THE LATEST GFS/ECMWF HAVE E/SE WINDS OF 45-55KTS
OVER THE FCST AREA BY 8 PM SAT. PLENTY OF ATLANTIC MOISTURE
ENTRAINMENT SHOULD BE ADVECTED INTO THE REGION FOR PERIODS OF
MDT-HVY RAIN BY SAT EVENING. HIGHS WILL BE BELOW NORMAL WITH MID
AND U60S COMMON IN THE LOWER ELEVATIONS AND M50S TO L60S OVER THE
HIGHER TERRAIN ACROSS THE CATSKILLS.
SATURDAY NIGHT...THIS WILL BE THE HIGHEST POTENTIAL IMPACT
PERIOD...AND WILL CONTINUE WHAT THE PREVIOUS SHIFT HIGHLIGHTED IN
THE SEGMENTED HWO. THE GEFS INDICATE ANOMALOUS LLJ WITH U-WIND
ANOMALIES 3 TO 5 STANDARD DEVIATIONS GREATER THAN NORMAL /STRONG
EASTERLIES/ AND STRONG V-WIND ANOMALIES /STRONG SOUTHERLIES/ 3 TO
5 STANDARD DEVIATIONS GREATER THAN NORMAL. HENCE...A SE LOW-LEVEL
JET MAX WILL FOCUS PERIODS OF MODERATE TO HEAVY RAINFALL. THE E/SE
FLOW WILL ENHANCE THE RAINFALL ALONG THE SPINE OF THE ERN
DACKS...ERN CATSKILLS...SRN GREENS..BERKS...AND NORTHERN LITCHFIELD
HILLS. PWATS LOOK TO BE 1 TO 2 STD DEVS ABOVE NORMAL...SLIGHTLY
HIGHER SOUTH AND EAST OF THE CAPITAL DISTRICT WHERE UP TO 3 STD IS
CURRENT PROGGED. THERE IS A SMALL WINDOW WHERE THE E/SE WINDS MAY
GUST CLOSE TO WIND ADVISORY LEVELS OVER THE SRN GREENS IN SRN
VT...NRN TACONICS...AND POSSIBLY THE NRN BERKS. IT WILL DEPEND ON
HOW MUCH MOMENTUM CAN BE TRANSFERRED TO SFC THROUGH A STRONG
INVERSION IN THE SOUNDINGS AND ITS OCCURRING NOCTURNALLY. WE WILL
MENTION THE THREAT AND CONTINUE WHAT THE DAY SHIFT HAS IN THE
HWO. IT IS HARD TO TELL HOW MUCH OF A THREAT THE RAIN WILL HAVE
FOR FLOODING AT THIS TIME. 1 TO 3 INCHES LOOKS POSSIBLE SAT PM
INTO SUNDAY MORNING BASED ON THE EC/WPC/CAN GGEM GUIDANCE...WITH
THE MESOSCALE MODELS SHOWING SOME 3-4 INCH AMOUNTS IN THE ERN
CATSKILLS...AND ERN DACKS. PER EXTENSIVE COLLABORATION FROM
SURROUNDING WFOS...CONFIDENCE REMAINS LOW FOR A FLOOD WATCH
AT THIS TIME...BUT WILL CONTINUE TO MONITOR AND MENTION IN THE
HWO. ZONE FFG VALUES REMAIN HIGH IN THE 3/6-HR TIME FRAME.
CATEGORICAL POPS WERE CONTINUED WITH RAIN...HVY AT
TIMES...SATURDAY NIGHT. IN ADDITION...SHOWALTER VALUES ARE PROGGED
EVEN LOWER WITH SUB ZERO VALUES ADVECTING INTO THE REGION TO
WARRANT AN INCLUSION OF THUNDERSTORMS OVERNIGHT. LOWS WILL BE
MAINLY IN THE 50S.
SUNDAY...MODEL TRENDS NOW WANT TO ADVECT IN A DRY SLOT DURING THE
DAY WHICH WILL REDUCE THE PRECIP COVERAGE AND INTENSITY ACROSS
MOST OF THE REGION FOR A SMALL WINDOW OF TIME. QUESTION IS IF WE
ARE ABLE TO SEE SOME INSOLATION TO ASSIST WITH DESTABILIZATION.
WHILE THE MAIN THRUST OF ADVECTION WILL BE WELL TO OUR NORTH...THE
VERTICALLY STACKED LOW ACROSS WESTERN NY WITH SECONDARY LOW
POSSIBLY TRACKING NORTH...NARROW LINES OF CONVECTION COULD EVOLVE.
WE WILL FOLLOW A BLENDED MOS VALUES WHICH REQUIRES A SLIGHT
ADJUSTMENT UPWARD IN THE AFTERNOON HIGH TEMPS TO LOWER HALF OF THE
70S FOR VALLEY LOCATIONS AND 60S ELSEWHERE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE LARGE VERTICALLY STACKED STORM SYSTEM IMPACTING THE REGION WILL
FINALLY START TO MOVE AWAY ON SUNDAY NIGHT...AS BOTH THE SFC AND
UPPER LEVEL LOWS MOVE FROM UPSTATE NY TOWARDS SOUTHERN QUEBEC AND
NORTHERN NEW ENGLAND. AS A RESULT...CHANCES FOR RAIN SHOWERS WILL
DECREASE THROUGH THE OVERNIGHT HOURS ON SUN NIGHT...ALTHOUGH WITH
CYCLONIC FLOW STILL IN PLACE...A FEW LIGHT RAIN SHOWERS AND PLENTY
OF CLOUDS REMAIN POSSIBLE. MIN TEMPS LOOK TO FALL INTO THE MID 50S
FOR MOST PLACES.
BY MONDAY...WEAK RIDGING ALOFT WILL POKE INTO THE REGION...ALLOWING
FOR PARTIAL SUNSHINE. CANNOT TOTALLY RULE OUT A BRIEF SHOWER...ESP
EARLY IN THE DAY...ACROSS THE ADIRONDACKS OR SRN GREENS...BUT MOST
AREAS LOOK TO STAY DRY. MAX TEMPS SHOULD REACH INTO THE MIDDLE TO
UPPER 70S FOR VALLEY AREAS...WITH 60S FOR THE HIGH TERRAIN. DRY
WEATHER LOOKS TO CONTINUE INTO MONDAY NIGHT WITH LOWS IN THE 50S
ONCE AGAIN.
WITHIN THE FLOW AT 500 HPA...ANOTHER SHORTWAVE TROUGH WILL ROTATE
TOWARDS THE REGION FROM THE GREAT LAKES. COMBINED WITH A MOIST
SOUTHERLY FLOW AND DAYTIME HEATING...A FEW ROUNDS OF SHOWERS AND
THUNDERSTORMS CAN BE EXPECTED FOR TUESDAY...ESP DURING THE AFTN AND
EVENING. CAN/T RULE OUT A FEW STRONG STORMS...ALTHOUGH WILL
ULTIMATELY DEPEND ON HOW MUCH INSTABILITY WILL BE IN PLACE. MAX
TEMPS LOOK TO REACH CLOSE TO 80 IN MANY VALLEY AREAS.
SHOWERS AND THUNDERSTORMS WILL WIND DOWN ON TUESDAY EVENING WITH THE
LOSS OF DAYTIME HEATING AND AS THE BEST UPPER LEVEL FORCING SHIFT
EASTWARD. HOWEVER...MORE SHOWERS AND THUNDERSTORMS ARE POSSIBLE ON
WEDNESDAY WITH THE BROAD UPPER LEVEL TROUGH REMAINING OVER THE AREA
AND ANOTHER SHORTWAVE ROTATING BY CLOSE TO THE REGION. TEMPS ONCE
AGAIN LOOK TO REACH THE UPPER 70S TO NEAR 80.
DRIER WEATHER LOOKS TO RETURN FOR THE LATE WEEK PERIOD...ALTHOUGH
THIS WILL BE DETERMINED BY JUST WHEN THE FLOW AT 500 HPA CAN FLATTEN
OUT. WILL CONTINUE SLIGHT TO LOW CHC POPS FOR THURSDAY DUE TO THE
UNCERTAINTY...WITH TEMPS MAINLY IN THE UPPER 70S.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
VFR CONDITIONS THROUGH THE FIRST 24 HOURS...EXCEPT PERHAPS MVFR
LAST COUPLE OF HOURS AT KPOU AS -RA MOVES IN TO LOWER VSBYS...PART
OF LOW PRESSURE DEEPENING OVER THE OHIO VALLEY AND HEADING EAST.
THINGS LOOK MUCH WORSE JUST BEYOND 24 HOURS...WITH MOISTURE AND
INSTABILITY INCREASING. ONLY SUB-MARGINAL SHEAR AT KPOU TOWARD 18Z
SAT. SFC WINDS SHOULD REMAIN UNDER 10 KTS AT ALL AIRPORTS.
OUTLOOK...
SATURDAY NIGHT: HIGH OPERATIONAL IMPACT. BREEZY DEFINITE RA...TSRA.
SUNDAY: HIGH OPERATIONAL IMPACT. BREEZY DEFINITE SHRA...TSRA.
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. BREEZY CHANCE OF SHRA.
MONDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
&&
.FIRE WEATHER...
MINIMAL TO LOW FIRE WEATHER RELATED CONCERNS THROUGH THE WEEKEND
AS ISOLATED TO SCATTERED SHOWERS PERSIST INTO THIS MORNING. A
BRIEF PERIOD OF DRY WEATHER IS EXPECTED LATER THIS AFTERNOON INTO
EARLY SATURDAY MORNING BEFORE A WIDESPREAD...SOAKING RAINFALL
OCCURS FOR THE MAJORITY OF THE REGION SATURDAY AFTERNOON INTO
SUNDAY MORNING.
THE RH VALUES WILL LOWER TO 40 TO 60 PERCENT TODAY WITH THE LOWER
VALUES NORTH OF THE MOHAWK RIVER VALLEY. THE RH VALUES WILL HAVE
AN EXCELLENT RECOVERY SATURDAY MORNING IN THE 75 TO 100 PERCENT
RANGE AND REMAIN HIGH THROUGH THE DAY AS WET WEATHER SPREADS
ACROSS THE ENTIRE REGION.
THE WINDS WILL LIGHT FROM THE NORTH TO NORTHWEST AT AROUND 10 MPH
TODAY...BECOMING LIGHT AND VARIABLE TO CALM WINDS FRIDAY NIGHT.
&&
.HYDROLOGY...
LIGHT RAIN SHOWERS WILL IMPACT MANY PORTIONS OF THE FORECAST AREA
THROUGH THIS MORNING WITH RAINFALL AMOUNTS GENERALLY ONE TENTH OF
AN INCH OR LESS.
DRIER WEATHER IS EXPECTED LATE THIS AFTERNOON INTO SATURDAY
MORNING BEFORE A STRONG LOW PRESSURE SYSTEM DEVELOPS NEAR THE OHIO
VALLEY AND MOVES TOWARDS THE EASTERN GREAT LAKES REGION. PERIODS
OF MODERATE TO HEAVY RAINFALL ARE POSSIBLE LATE SATURDAY AFTERNOON
INTO SUNDAY...DEPENDING ON THE EVENTUAL TRACK AND EVOLUTION OF LOW
PRESSURE DEVELOPING ACROSS THE OHIO VALLEY REGION.
RIGHT NOW...ONE TO UP TO TWO INCHES OF RAINFALL ARE POSSIBLE
ACROSS THE HSA WITH UP TO 3 INCHES OR SO OVER THE EASTERN
CATSKILLS...AND POSSIBLE THE EASTERN ADIRONDACKS. THE TRACK AND
RAINFALL DURATION WILL DETERMINE WHERE THE HIGHER AMOUNTS WILL OCCUR.
THE LATEST MMEFS GUIDANCE CONTINUES TO SUGGEST WITHIN BANK RISES
TO THE CAUTION OR ALERT STAGES AT A FEW SITES AT THIS TIME.
URBAN AND SMALL STREAM CONCERNS ACROSS THE HSA WILL HAVE TO BE
MONITORED...AND WILL MENTION IN THE HWO. ALSO...IF CONFIDENCE
INCREASES FOR THE POTENTIAL OF WIDESPREAD MINOR FLOODING...THEN A
FLOOD WATCH MAY BE NEEDED FOR PORTIONS OF THE HSA LATER IN TIME.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR
WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...BGM/WASULA
NEAR TERM...GJM/BGM/WASULA
SHORT TERM...BGM/WASULA
LONG TERM...FRUGIS
AVIATION...ELH
FIRE WEATHER...BGM/WASULA
HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
138 PM EDT FRI JUN 26 2015
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE REGION THIS
AFTERNOON WITH ISOLATED SHOWERS MAINLY FROM THE MOHAWK VALLEY
SOUTH AND EAST. THEREAFTER...HIGH PRESSURE WILL BUILD OVER THE
REGION LATE THIS AFTERNOON INTO THIS EVENING...RESULTING IN A
BRIEF PERIOD OF FAIR AND DRY WEATHER. AN INTENSIFYING STORM OVER
THE OHIO VALLEY WILL APPROACH ON SATURDAY...BRINGING PERIODS OF
RAIN AND COOL CONDITIONS FOR THIS FIRST FULL WEEKEND OF SUMMER.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 130 PM EDT...THIS UPDATE IS TO MAKE MINOR ADJUSTMENTS TO THE
POP...WX...SKY COVER...HOURLY TEMPS AND MAX TEMP GRIGDS FOR THIS
AFTERNOON.
PREVIOUS DISCUSSION...
THE COLD FRONT HAS SLIPPED SOUTH OF THE REGION WITH THE MAIN
FEATURE OF INTEREST THE UPPER LEVEL TROUGH AXIS MOVING TOWARDS THE
ST LAWRENCE RIVER VALLEY PER THE LATEST HRRR/RAP40/NAM. PARTLY
CLOUDY/MOSTLY CLEAR CONDITIONS WILL BECOME MOSTLY CLOUDY FROM THE
CAPITAL REGION/MOHAWK VALLEY SOUTH WITH THE UPPER TROUGH PASSAGE
THIS AFTERNOON. SOME ISOLD SHOWERS ARE POSSIBLE DUE TO THE
CYCLONIC VORTICITY ADVECTION DUE TO THE SHORT- WAVE ROTATING
AROUND THE UPPER LOW. SOME SCT SHOWERS ARE POSSIBLE OVER THE
HIGHER TERRAIN. ANY RAINFALL AMOUNTS SHOULD BE LIGHT WITH A FEW
HUNDREDTHS. THE LATEST HRRR INDICATES THE SHOWER SHOULD DIMINISH
NORTH OF THE CAPITAL REGION/MOHAWK VALLEY IN THE EARLY PM.
HIGHS MOSTLY 70 TO 80 WITH SOME UPPER 60S OVER THE HIGHER TERRAIN.
INTO TONIGHT...SURFACE HIGH BUILDS AND CRESTS ACROSS THE REGION
FOR A TRANQUIL PERIOD OF WEATHER. A LIGHT NORTHERLY WIND WILL
SUBSIDE TO LIGHT AND VARIABLE UNDER PTCLOUDY-MOCLEAR SKIES.
HOWEVER...THE METEOROLOGICAL EYES WILL BE WATCHING WHAT TRANSPIRES
UPSTREAM AS NCEP MODEL SUITE AND INTERNATIONAL GUIDANCE ARE
BECOMING MORE IN AGREEMENT WITH AN ANOMALOUS DIGGING/PHASING
TROUGH ACROSS THE MID WEST WITH EXPANDING AREA OF CLOUDS AND
RAIN/SHOWERS. CLOUD COVERAGE MAY APPROACHING OUR SOUTHERN MOST
ZONES OVERNIGHT BUT IT WILL REMAIN DRY. OVERNIGHT LOWS MAINLY INTO
THE 50S WITH SOME UPPER 40S ACROSS PORTIONS OF THE
DACKS...BERKS...SOUTHERN GREENS.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
IMPRESSIVE STORM TO DEVELOP ACROSS THE OHIO VALLEY AND IMPACT
OUR REGION THIS WEEKEND...
THE PREVIOUS EXCELLENT AFD FOLLOWS WITH MINOR UPDATES PER THE 00Z
GUIDANCE.
SATURDAY...THE 26/00Z ECMWF SHOWS THE SFC WAVE MOVING A LITTLE
SLOWER TOWARDS A MID LEVEL JET CONFLUENT REGION OVER E-OH AND W-PA
BY MID MORNING. THE ISENTROPIC LIFT INCREASES QUICKLY ON THE
290-300K SFC BY THE LATE MORNING INTO THE AFTERNOON ESPECIALLY
SOUTH AND WEST OF THE CAPITAL REGION. THE LOW-LEVEL BAROCLINIC
LEAFLET STRENGTHENS BETWEEN THE RETREATING AND STRENGTHENING HIGH
OFF THE NEW ENGLAND COAST /1022MB/ ...AND THE LOW PRESSURE SYSTEM
MOVING TOWARDS LAKE ERIE AND WRN PA BY THE EARLY PM WITH SUB
1000MB EXPECTED. THE GFS/ECMWF ATTEMPT TO HAVE A SECONDARY LOW
FORM OVER THE MID ATLANTIC REGION THROUGH THE AFTERNOON. OVER
RUNNING RAINFALL AHEAD OF THE PRIMARY SFC CYCLONE...AND THE WARM
FRONT SHOULD OVER SPREAD THE REGION BY THE EARLY EVENING. AN
ANOMALOUS H850/925 E/SE LLJ INCREASES AHEAD OF THE SFC WAVE TO
BETTER THAN 40KTS. THE LATEST GFS/ECMWF HAVE E/SE WINDS OF 45-55KTS
OVER THE FCST AREA BY 8 PM SAT. PLENTY OF ATLANTIC MOISTURE
ENTRAINMENT SHOULD BE ADVECTED INTO THE REGION FOR PERIODS OF
MDT-HVY RAIN BY SAT EVENING. HIGHS WILL BE BELOW NORMAL WITH MID
AND U60S COMMON IN THE LOWER ELEVATIONS AND M50S TO L60S OVER THE
HIGHER TERRAIN ACROSS THE CATSKILLS.
SATURDAY NIGHT...THIS WILL BE THE HIGHEST POTENTIAL IMPACT
PERIOD...AND WILL CONTINUE WHAT THE PREVIOUS SHIFT HIGHLIGHTED IN
THE SEGMENTED HWO. THE GEFS INDICATE ANOMALOUS LLJ WITH U-WIND
ANOMALIES 3 TO 5 STANDARD DEVIATIONS GREATER THAN NORMAL /STRONG
EASTERLIES/ AND STRONG V-WIND ANOMALIES /STRONG SOUTHERLIES/ 3 TO
5 STANDARD DEVIATIONS GREATER THAN NORMAL. HENCE...A SE LOW-LEVEL
JET MAX WILL FOCUS PERIODS OF MODERATE TO HEAVY RAINFALL. THE E/SE
FLOW WILL ENHANCE THE RAINFALL ALONG THE SPINE OF THE ERN
DACKS...ERN CATSKILLS...SRN GREENS..BERKS...AND NORTHERN LITCHFIELD
HILLS. PWATS LOOK TO BE 1 TO 2 STD DEVS ABOVE NORMAL...SLIGHTLY
HIGHER SOUTH AND EAST OF THE CAPITAL DISTRICT WHERE UP TO 3 STD IS
CURRENT PROGGED. THERE IS A SMALL WINDOW WHERE THE E/SE WINDS MAY
GUST CLOSE TO WIND ADVISORY LEVELS OVER THE SRN GREENS IN SRN
VT...NRN TACONICS...AND POSSIBLY THE NRN BERKS. IT WILL DEPEND ON
HOW MUCH MOMENTUM CAN BE TRANSFERRED TO SFC THROUGH A STRONG
INVERSION IN THE SOUNDINGS AND ITS OCCURRING NOCTURNALLY. WE WILL
MENTION THE THREAT AND CONTINUE WHAT THE DAY SHIFT HAS IN THE
HWO. IT IS HARD TO TELL HOW MUCH OF A THREAT THE RAIN WILL HAVE
FOR FLOODING AT THIS TIME. 1 TO 3 INCHES LOOKS POSSIBLE SAT PM
INTO SUNDAY MORNING BASED ON THE EC/WPC/CAN GGEM GUIDANCE...WITH
THE MESOSCALE MODELS SHOWING SOME 3-4 INCH AMOUNTS IN THE ERN
CATSKILLS...AND ERN DACKS. PER EXTENSIVE COLLABORATION FROM
SURROUNDING WFOS...CONFIDENCE REMAINS LOW FOR A FLOOD WATCH
AT THIS TIME...BUT WILL CONTINUE TO MONITOR AND MENTION IN THE
HWO. ZONE FFG VALUES REMAIN HIGH IN THE 3/6-HR TIME FRAME.
CATEGORICAL POPS WERE CONTINUED WITH RAIN...HVY AT
TIMES...SATURDAY NIGHT. IN ADDITION...SHOWALTER VALUES ARE PROGGED
EVEN LOWER WITH SUB ZERO VALUES ADVECTING INTO THE REGION TO
WARRANT AN INCLUSION OF THUNDERSTORMS OVERNIGHT. LOWS WILL BE
MAINLY IN THE 50S.
SUNDAY...MODEL TRENDS NOW WANT TO ADVECT IN A DRY SLOT DURING THE
DAY WHICH WILL REDUCE THE PRECIP COVERAGE AND INTENSITY ACROSS
MOST OF THE REGION FOR A SMALL WINDOW OF TIME. QUESTION IS IF WE
ARE ABLE TO SEE SOME INSOLATION TO ASSIST WITH DESTABILIZATION.
WHILE THE MAIN THRUST OF ADVECTION WILL BE WELL TO OUR NORTH...THE
VERTICALLY STACKED LOW ACROSS WESTERN NY WITH SECONDARY LOW
POSSIBLY TRACKING NORTH...NARROW LINES OF CONVECTION COULD EVOLVE.
WE WILL FOLLOW A BLENDED MOS VALUES WHICH REQUIRES A SLIGHT
ADJUSTMENT UPWARD IN THE AFTERNOON HIGH TEMPS TO LOWER HALF OF THE
70S FOR VALLEY LOCATIONS AND 60S ELSEWHERE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE LARGE VERTICALLY STACKED STORM SYSTEM IMPACTING THE REGION WILL
FINALLY START TO MOVE AWAY ON SUNDAY NIGHT...AS BOTH THE SFC AND
UPPER LEVEL LOWS MOVE FROM UPSTATE NY TOWARDS SOUTHERN QUEBEC AND
NORTHERN NEW ENGLAND. AS A RESULT...CHANCES FOR RAIN SHOWERS WILL
DECREASE THROUGH THE OVERNIGHT HOURS ON SUN NIGHT...ALTHOUGH WITH
CYCLONIC FLOW STILL IN PLACE...A FEW LIGHT RAIN SHOWERS AND PLENTY
OF CLOUDS REMAIN POSSIBLE. MIN TEMPS LOOK TO FALL INTO THE MID 50S
FOR MOST PLACES.
BY MONDAY...WEAK RIDGING ALOFT WILL POKE INTO THE REGION...ALLOWING
FOR PARTIAL SUNSHINE. CANNOT TOTALLY RULE OUT A BRIEF SHOWER...ESP
EARLY IN THE DAY...ACROSS THE ADIRONDACKS OR SRN GREENS...BUT MOST
AREAS LOOK TO STAY DRY. MAX TEMPS SHOULD REACH INTO THE MIDDLE TO
UPPER 70S FOR VALLEY AREAS...WITH 60S FOR THE HIGH TERRAIN. DRY
WEATHER LOOKS TO CONTINUE INTO MONDAY NIGHT WITH LOWS IN THE 50S
ONCE AGAIN.
WITHIN THE FLOW AT 500 HPA...ANOTHER SHORTWAVE TROUGH WILL ROTATE
TOWARDS THE REGION FROM THE GREAT LAKES. COMBINED WITH A MOIST
SOUTHERLY FLOW AND DAYTIME HEATING...A FEW ROUNDS OF SHOWERS AND
THUNDERSTORMS CAN BE EXPECTED FOR TUESDAY...ESP DURING THE AFTN AND
EVENING. CAN/T RULE OUT A FEW STRONG STORMS...ALTHOUGH WILL
ULTIMATELY DEPEND ON HOW MUCH INSTABILITY WILL BE IN PLACE. MAX
TEMPS LOOK TO REACH CLOSE TO 80 IN MANY VALLEY AREAS.
SHOWERS AND THUNDERSTORMS WILL WIND DOWN ON TUESDAY EVENING WITH THE
LOSS OF DAYTIME HEATING AND AS THE BEST UPPER LEVEL FORCING SHIFT
EASTWARD. HOWEVER...MORE SHOWERS AND THUNDERSTORMS ARE POSSIBLE ON
WEDNESDAY WITH THE BROAD UPPER LEVEL TROUGH REMAINING OVER THE AREA
AND ANOTHER SHORTWAVE ROTATING BY CLOSE TO THE REGION. TEMPS ONCE
AGAIN LOOK TO REACH THE UPPER 70S TO NEAR 80.
DRIER WEATHER LOOKS TO RETURN FOR THE LATE WEEK PERIOD...ALTHOUGH
THIS WILL BE DETERMINED BY JUST WHEN THE FLOW AT 500 HPA CAN FLATTEN
OUT. WILL CONTINUE SLIGHT TO LOW CHC POPS FOR THURSDAY DUE TO THE
UNCERTAINTY...WITH TEMPS MAINLY IN THE UPPER 70S.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
VFR CONDITIONS THROUGH THE
FIRST 24 HOURS...EXCEPT PERHAPS MVFR LAST COUPLE OF HOURS AT KPOU AS
-RA MOVES IN TO LOWER VSBYS...PART OF LOW PRESSURE DEEPENING OVER
THE OHIO VALLEY AND HEADING EAST. THINGS LOOK MUCH WORSE JUST
BEYOND 24 HOURS...WITH MOISTURE AND INSTABILITY INCREASING. ONLY
SUB-MARGINAL SHEAR AT KPOU TOWARD 18Z SAT. SFC WINDS SHOULD REMAIN
UNDER 10 KTS AT ALL AIRPORTS.
OUTLOOK...
SATURDAY NIGHT: HIGH OPERATIONAL IMPACT. BREEZY DEFINITE RA...TSRA.
SUNDAY: HIGH OPERATIONAL IMPACT. BREEZY DEFINITE SHRA...TSRA.
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. BREEZY CHANCE OF SHRA.
MONDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
&&
.FIRE WEATHER...
MINIMAL TO LOW FIRE WEATHER RELATED CONCERNS THROUGH THE WEEKEND
AS ISOLATED TO SCATTERED SHOWERS PERSIST INTO THIS MORNING. A
BRIEF PERIOD OF DRY WEATHER IS EXPECTED LATER THIS AFTERNOON INTO
EARLY SATURDAY MORNING BEFORE A WIDESPREAD...SOAKING RAINFALL
OCCURS FOR THE MAJORITY OF THE REGION SATURDAY AFTERNOON INTO
SUNDAY MORNING.
THE RH VALUES WILL LOWER TO 40 TO 60 PERCENT TODAY WITH THE LOWER
VALUES NORTH OF THE MOHAWK RIVER VALLEY. THE RH VALUES WILL HAVE
AN EXCELLENT RECOVERY SATURDAY MORNING IN THE 75 TO 100 PERCENT
RANGE AND REMAIN HIGH THROUGH THE DAY AS WET WEATHER SPREADS
ACROSS THE ENTIRE REGION.
THE WINDS WILL LIGHT FROM THE NORTH TO NORTHWEST AT AROUND 10 MPH
TODAY...BECOMING LIGHT AND VARIABLE TO CALM WINDS FRIDAY NIGHT.
&&
.HYDROLOGY...
LIGHT RAIN SHOWERS WILL IMPACT MANY PORTIONS OF THE FORECAST AREA
THROUGH THIS MORNING WITH RAINFALL AMOUNTS GENERALLY ONE TENTH OF
AN INCH OR LESS.
DRIER WEATHER IS EXPECTED LATE THIS AFTERNOON INTO SATURDAY
MORNING BEFORE A STRONG LOW PRESSURE SYSTEM DEVELOPS NEAR THE OHIO
VALLEY AND MOVES TOWARDS THE EASTERN GREAT LAKES REGION. PERIODS
OF MODERATE TO HEAVY RAINFALL ARE POSSIBLE LATE SATURDAY AFTERNOON
INTO SUNDAY...DEPENDING ON THE EVENTUAL TRACK AND EVOLUTION OF LOW
PRESSURE DEVELOPING ACROSS THE OHIO VALLEY REGION.
RIGHT NOW...ONE TO UP TO TWO INCHES OF RAINFALL ARE POSSIBLE
ACROSS THE HSA WITH UP TO 3 INCHES OR SO OVER THE EASTERN
CATSKILLS...AND POSSIBLE THE EASTERN ADIRONDACKS. THE TRACK AND
RAINFALL DURATION WILL DETERMINE WHERE THE HIGHER AMOUNTS WILL OCCUR.
THE LATEST MMEFS GUIDANCE CONTINUES TO SUGGEST WITHIN BANK RISES
TO THE CAUTION OR ALERT STAGES AT A FEW SITES AT THIS TIME.
URBAN AND SMALL STREAM CONCERNS ACROSS THE HSA WILL HAVE TO BE
MONITORED...AND WILL MENTION IN THE HWO. ALSO...IF CONFIDENCE
INCREASES FOR THE POTENTIAL OF WIDESPREAD MINOR FLOODING...THEN A
FLOOD WATCH MAY BE NEEDED FOR PORTIONS OF THE HSA LATER IN TIME.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR
WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...BGM/WASULA
NEAR TERM...GJM/BGM/WASULA
SHORT TERM...BGM/WASULA
LONG TERM...FRUGIS
AVIATION...FRUGIS
FIRE WEATHER...BGM/WASULA
HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
131 PM EDT FRI JUN 26 2015
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE REGION THIS
AFTERNOON WITH ISOLATED SHOWERS MAINLY FROM THE MOHAWK VALLEY
SOUTH AND EAST. THEREAFTER...HIGH PRESSURE WILL BUILD OVER THE
REGION LATE THIS AFTERNOON INTO THIS EVENING...RESULTING IN A
BRIEF PERIOD OF FAIR AND DRY WEATHER. AN INTENSIFYING STORM OVER
THE OHIO VALLEY WILL APPROACH ON SATURDAY...BRINGING PERIODS OF
RAIN AND COOL CONDITIONS FOR THIS FIRST FULL WEEKEND OF SUMMER.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 959 AM EDT...THIS UPDATE IS TO RETOOL THE POP TRENDS AND
CLOUD COVERAGE ACROSS THE REGION. THE COLD FRONT HAS SLIPPED SOUTH
OF THE REGION WITH THE MAIN FEATURE OF INTEREST THE UPPER LEVEL
TROUGH AXIS MOVING TOWARDS THE ST LAWRENCE RIVER VALLEY PER THE
LATEST HRRR/RAP40/NAM. PARTLY CLOUDY/MOSTLY CLEAR CONDITIONS WILL
BECOME MOSTLY CLOUDY FROM THE CAPITAL REGION/MOHAWK VALLEY SOUTH
WITH THE UPPER TROUGH PASSAGE THIS AFTERNOON. SOME ISOLD SHOWERS
ARE POSSIBLE DUE TO THE CYCLONIC VORTICITY ADVECTION DUE TO THE
SHORT-WAVE ROTATING AROUND THE UPPER LOW. SOME SCT SHOWERS ARE
POSSIBLE OVER THE HIGHER TERRAIN. ANY RAINFALL AMOUNTS SHOULD BE
LIGHT WITH A FEW HUNDREDTHS. THE LATEST HRRR INDICATES THE SHOWER
SHOULD DIMINISH NORTH OF THE CAPITAL REGION/MOHAWK VALLEY IN THE
EARLY PM.
HIGHS MOSTLY IN THE MID TO UPPER 70S FOR VALLEY LOCATIONS WITH
UPPER 60S TO LOWER 70S FOR THE HIGHER TERRAIN.
INTO TONIGHT...SURFACE HIGH BUILDS AND CRESTS ACROSS THE REGION
FOR A TRANQUIL PERIOD OF WEATHER. A LIGHT NORTHERLY WIND WILL
SUBSIDE TO LIGHT AND VARIABLE UNDER PTCLOUDY-MOCLEAR SKIES.
HOWEVER...THE METEOROLOGICAL EYES WILL BE WATCHING WHAT TRANSPIRES
UPSTREAM AS NCEP MODEL SUITE AND INTERNATIONAL GUIDANCE ARE
BECOMING MORE IN AGREEMENT WITH AN ANOMALOUS DIGGING/PHASING
TROUGH ACROSS THE MID WEST WITH EXPANDING AREA OF CLOUDS AND
RAIN/SHOWERS. CLOUD COVERAGE MAY APPROACHING OUR SOUTHERN MOST
ZONES OVERNIGHT BUT IT WILL REMAIN DRY. OVERNIGHT LOWS MAINLY INTO
THE 50S WITH SOME UPPER 40S ACROSS PORTIONS OF THE
DACKS...BERKS...SOUTHERN GREENS.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
IMPRESSIVE STORM TO DEVELOP ACROSS THE OHIO VALLEY AND IMPACT
OUR REGION THIS WEEKEND...
THE PREVIOUS EXCELLENT AFD FOLLOWS WITH MINOR UPDATES PER THE 00Z
GUIDANCE.
SATURDAY...THE 26/00Z ECMWF SHOWS THE SFC WAVE MOVING A LITTLE
SLOWER TOWARDS A MID LEVEL JET CONFLUENT REGION OVER E-OH AND W-PA
BY MID MORNING. THE ISENTROPIC LIFT INCREASES QUICKLY ON THE
290-300K SFC BY THE LATE MORNING INTO THE AFTERNOON ESPECIALLY
SOUTH AND WEST OF THE CAPITAL REGION. THE LOW-LEVEL BAROCLINIC
LEAFLET STRENGTHENS BETWEEN THE RETREATING AND STRENGTHENING HIGH
OFF THE NEW ENGLAND COAST /1022MB/ ...AND THE LOW PRESSURE SYSTEM
MOVING TOWARDS LAKE ERIE AND WRN PA BY THE EARLY PM WITH SUB
1000MB EXPECTED. THE GFS/ECMWF ATTEMPT TO HAVE A SECONDARY LOW
FORM OVER THE MID ATLANTIC REGION THROUGH THE AFTERNOON. OVER
RUNNING RAINFALL AHEAD OF THE PRIMARY SFC CYCLONE...AND THE WARM
FRONT SHOULD OVER SPREAD THE REGION BY THE EARLY EVENING. AN
ANOMALOUS H850/925 E/SE LLJ INCREASES AHEAD OF THE SFC WAVE TO
BETTER THAN 40KTS. THE LATEST GFS/ECMWF HAVE E/SE WINDS OF 45-55KTS
OVER THE FCST AREA BY 8 PM SAT. PLENTY OF ATLANTIC MOISTURE
ENTRAINMENT SHOULD BE ADVECTED INTO THE REGION FOR PERIODS OF
MDT-HVY RAIN BY SAT EVENING. HIGHS WILL BE BELOW NORMAL WITH MID
AND U60S COMMON IN THE LOWER ELEVATIONS AND M50S TO L60S OVER THE
HIGHER TERRAIN ACROSS THE CATSKILLS.
SATURDAY NIGHT...THIS WILL BE THE HIGHEST POTENTIAL IMPACT
PERIOD...AND WILL CONTINUE WHAT THE PREVIOUS SHIFT HIGHLIGHTED IN
THE SEGMENTED HWO. THE GEFS INDICATE ANOMALOUS LLJ WITH U-WIND
ANOMALIES 3 TO 5 STANDARD DEVIATIONS GREATER THAN NORMAL /STRONG
EASTERLIES/ AND STRONG V-WIND ANOMALIES /STRONG SOUTHERLIES/ 3 TO
5 STANDARD DEVIATIONS GREATER THAN NORMAL. HENCE...A SE LOW-LEVEL
JET MAX WILL FOCUS PERIODS OF MODERATE TO HEAVY RAINFALL. THE E/SE
FLOW WILL ENHANCE THE RAINFALL ALONG THE SPINE OF THE ERN
DACKS...ERN CATSKILLS...SRN GREENS..BERKS...AND NORTHERN LITCHFIELD
HILLS. PWATS LOOK TO BE 1 TO 2 STD DEVS ABOVE NORMAL...SLIGHTLY
HIGHER SOUTH AND EAST OF THE CAPITAL DISTRICT WHERE UP TO 3 STD IS
CURRENT PROGGED. THERE IS A SMALL WINDOW WHERE THE E/SE WINDS MAY
GUST CLOSE TO WIND ADVISORY LEVELS OVER THE SRN GREENS IN SRN
VT...NRN TACONICS...AND POSSIBLY THE NRN BERKS. IT WILL DEPEND ON
HOW MUCH MOMENTUM CAN BE TRANSFERRED TO SFC THROUGH A STRONG
INVERSION IN THE SOUNDINGS AND ITS OCCURRING NOCTURNALLY. WE WILL
MENTION THE THREAT AND CONTINUE WHAT THE DAY SHIFT HAS IN THE
HWO. IT IS HARD TO TELL HOW MUCH OF A THREAT THE RAIN WILL HAVE
FOR FLOODING AT THIS TIME. 1 TO 3 INCHES LOOKS POSSIBLE SAT PM
INTO SUNDAY MORNING BASED ON THE EC/WPC/CAN GGEM GUIDANCE...WITH
THE MESOSCALE MODELS SHOWING SOME 3-4 INCH AMOUNTS IN THE ERN
CATSKILLS...AND ERN DACKS. PER EXTENSIVE COLLABORATION FROM
SURROUNDING WFOS...CONFIDENCE REMAINS LOW FOR A FLOOD WATCH
AT THIS TIME...BUT WILL CONTINUE TO MONITOR AND MENTION IN THE
HWO. ZONE FFG VALUES REMAIN HIGH IN THE 3/6-HR TIME FRAME.
CATEGORICAL POPS WERE CONTINUED WITH RAIN...HVY AT
TIMES...SATURDAY NIGHT. IN ADDITION...SHOWALTER VALUES ARE PROGGED
EVEN LOWER WITH SUB ZERO VALUES ADVECTING INTO THE REGION TO
WARRANT AN INCLUSION OF THUNDERSTORMS OVERNIGHT. LOWS WILL BE
MAINLY IN THE 50S.
SUNDAY...MODEL TRENDS NOW WANT TO ADVECT IN A DRY SLOT DURING THE
DAY WHICH WILL REDUCE THE PRECIP COVERAGE AND INTENSITY ACROSS
MOST OF THE REGION FOR A SMALL WINDOW OF TIME. QUESTION IS IF WE
ARE ABLE TO SEE SOME INSOLATION TO ASSIST WITH DESTABILIZATION.
WHILE THE MAIN THRUST OF ADVECTION WILL BE WELL TO OUR NORTH...THE
VERTICALLY STACKED LOW ACROSS WESTERN NY WITH SECONDARY LOW
POSSIBLY TRACKING NORTH...NARROW LINES OF CONVECTION COULD EVOLVE.
WE WILL FOLLOW A BLENDED MOS VALUES WHICH REQUIRES A SLIGHT
ADJUSTMENT UPWARD IN THE AFTERNOON HIGH TEMPS TO LOWER HALF OF THE
70S FOR VALLEY LOCATIONS AND 60S ELSEWHERE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE LARGE VERTICALLY STACKED STORM SYSTEM IMPACTING THE REGION WILL
FINALLY START TO MOVE AWAY ON SUNDAY NIGHT...AS BOTH THE SFC AND
UPPER LEVEL LOWS MOVE FROM UPSTATE NY TOWARDS SOUTHERN QUEBEC AND
NORTHERN NEW ENGLAND. AS A RESULT...CHANCES FOR RAIN SHOWERS WILL
DECREASE THROUGH THE OVERNIGHT HOURS ON SUN NIGHT...ALTHOUGH WITH
CYCLONIC FLOW STILL IN PLACE...A FEW LIGHT RAIN SHOWERS AND PLENTY
OF CLOUDS REMAIN POSSIBLE. MIN TEMPS LOOK TO FALL INTO THE MID 50S
FOR MOST PLACES.
BY MONDAY...WEAK RIDGING ALOFT WILL POKE INTO THE REGION...ALLOWING
FOR PARTIAL SUNSHINE. CANNOT TOTALLY RULE OUT A BRIEF SHOWER...ESP
EARLY IN THE DAY...ACROSS THE ADIRONDACKS OR SRN GREENS...BUT MOST
AREAS LOOK TO STAY DRY. MAX TEMPS SHOULD REACH INTO THE MIDDLE TO
UPPER 70S FOR VALLEY AREAS...WITH 60S FOR THE HIGH TERRAIN. DRY
WEATHER LOOKS TO CONTINUE INTO MONDAY NIGHT WITH LOWS IN THE 50S
ONCE AGAIN.
WITHIN THE FLOW AT 500 HPA...ANOTHER SHORTWAVE TROUGH WILL ROTATE
TOWARDS THE REGION FROM THE GREAT LAKES. COMBINED WITH A MOIST
SOUTHERLY FLOW AND DAYTIME HEATING...A FEW ROUNDS OF SHOWERS AND
THUNDERSTORMS CAN BE EXPECTED FOR TUESDAY...ESP DURING THE AFTN AND
EVENING. CAN/T RULE OUT A FEW STRONG STORMS...ALTHOUGH WILL
ULTIMATELY DEPEND ON HOW MUCH INSTABILITY WILL BE IN PLACE. MAX
TEMPS LOOK TO REACH CLOSE TO 80 IN MANY VALLEY AREAS.
SHOWERS AND THUNDERSTORMS WILL WIND DOWN ON TUESDAY EVENING WITH THE
LOSS OF DAYTIME HEATING AND AS THE BEST UPPER LEVEL FORCING SHIFT
EASTWARD. HOWEVER...MORE SHOWERS AND THUNDERSTORMS ARE POSSIBLE ON
WEDNESDAY WITH THE BROAD UPPER LEVEL TROUGH REMAINING OVER THE AREA
AND ANOTHER SHORTWAVE ROTATING BY CLOSE TO THE REGION. TEMPS ONCE
AGAIN LOOK TO REACH THE UPPER 70S TO NEAR 80.
DRIER WEATHER LOOKS TO RETURN FOR THE LATE WEEK PERIOD...ALTHOUGH
THIS WILL BE DETERMINED BY JUST WHEN THE FLOW AT 500 HPA CAN FLATTEN
OUT. WILL CONTINUE SLIGHT TO LOW CHC POPS FOR THURSDAY DUE TO THE
UNCERTAINTY...WITH TEMPS MAINLY IN THE UPPER 70S.
&&
.AVIATION /18Z FRIDAY THROUGH TUESDAY/... VFR CONDITIONS THROUGH THE
FIRST 24 HOURS...EXCEPT PERHAPS MVFR LAST COUPLE OF HOURS AT KPOU AS
-RA MOVES IN TO LOWER VSBYS...PART OF LOW PRESSURE DEEPENING OVER
THE OHIO VALLEY AND HEADING EAST. THINGS LOOK MUCH WORSE JUST
BEYOND 24 HOURS...WITH MOISTURE AND INSTABILITY INCREASING. ONLY
SUB-MARGINAL SHEAR AT KPOU TOWARD 18Z SAT. SFC WINDS SHOULD REMAIN
UNDER 10 KTS AT ALL AIRPORTS.
OUTLOOK...
SATURDAY NIGHT: HIGH OPERATIONAL IMPACT. BREEZY DEFINITE RA...TSRA.
SUNDAY: HIGH OPERATIONAL IMPACT. BREEZY DEFINITE SHRA...TSRA.
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. BREEZY CHANCE OF SHRA.
MONDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
&&
.FIRE WEATHER...
MINIMAL TO LOW FIRE WEATHER RELATED CONCERNS THROUGH THE WEEKEND
AS ISOLATED TO SCATTERED SHOWERS PERSIST INTO THIS MORNING. A
BRIEF PERIOD OF DRY WEATHER IS EXPECTED LATER THIS AFTERNOON INTO
EARLY SATURDAY MORNING BEFORE A WIDESPREAD...SOAKING RAINFALL
OCCURS FOR THE MAJORITY OF THE REGION SATURDAY AFTERNOON INTO
SUNDAY MORNING.
THE RH VALUES WILL LOWER TO 40 TO 60 PERCENT TODAY WITH THE LOWER
VALUES NORTH OF THE MOHAWK RIVER VALLEY. THE RH VALUES WILL HAVE
AN EXCELLENT RECOVERY SATURDAY MORNING IN THE 75 TO 100 PERCENT
RANGE AND REMAIN HIGH THROUGH THE DAY AS WET WEATHER SPREADS
ACROSS THE ENTIRE REGION.
THE WINDS WILL LIGHT FROM THE NORTH TO NORTHWEST AT AROUND 10 MPH
TODAY...BECOMING LIGHT AND VARIABLE TO CALM WINDS FRIDAY NIGHT.
&&
.HYDROLOGY...
LIGHT RAIN SHOWERS WILL IMPACT MANY PORTIONS OF THE FORECAST AREA
THROUGH THIS MORNING WITH RAINFALL AMOUNTS GENERALLY ONE TENTH OF
AN INCH OR LESS.
DRIER WEATHER IS EXPECTED LATE THIS AFTERNOON INTO SATURDAY
MORNING BEFORE A STRONG LOW PRESSURE SYSTEM DEVELOPS NEAR THE OHIO
VALLEY AND MOVES TOWARDS THE EASTERN GREAT LAKES REGION. PERIODS
OF MODERATE TO HEAVY RAINFALL ARE POSSIBLE LATE SATURDAY AFTERNOON
INTO SUNDAY...DEPENDING ON THE EVENTUAL TRACK AND EVOLUTION OF LOW
PRESSURE DEVELOPING ACROSS THE OHIO VALLEY REGION.
RIGHT NOW...ONE TO UP TO TWO INCHES OF RAINFALL ARE POSSIBLE
ACROSS THE HSA WITH UP TO 3 INCHES OR SO OVER THE EASTERN
CATSKILLS...AND POSSIBLE THE EASTERN ADIRONDACKS. THE TRACK AND
RAINFALL DURATION WILL DETERMINE WHERE THE HIGHER AMOUNTS WILL OCCUR.
THE LATEST MMEFS GUIDANCE CONTINUES TO SUGGEST WITHIN BANK RISES
TO THE CAUTION OR ALERT STAGES AT A FEW SITES AT THIS TIME.
URBAN AND SMALL STREAM CONCERNS ACROSS THE HSA WILL HAVE TO BE
MONITORED...AND WILL MENTION IN THE HWO. ALSO...IF CONFIDENCE
INCREASES FOR THE POTENTIAL OF WIDESPREAD MINOR FLOODING...THEN A
FLOOD WATCH MAY BE NEEDED FOR PORTIONS OF THE HSA LATER IN TIME.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR
WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...BGM/WASULA
NEAR TERM...BGM/WASULA
SHORT TERM...BGM/WASULA
LONG TERM...FRUGIS
AVIATION...ELH
FIRE WEATHER...BGM/WASULA
HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
525 PM EDT FRI JUN 26 2015
.SYNOPSIS...
THUNDERSTORMS WILL BE SCATTERED WELL AHEAD OF A COLD FRONT
THROUGH TONIGHT. THUNDERSTORM COVERAGE WILL INCREASE FOR SATURDAY
AS THE FRONT GETS CLOSER TO THE AREA. THE FRONT WILL CROSS THE
AREA SATURDAY NIGHT WITH DRY CONDITIONS AND TEMPERATURES NEAR
NORMAL ARRIVING EARLY NEXT WEEK.
&&
.NEAR TERM /TONIGHT/...
CONVERGENCE INTO THE HEAT TROUGH OVER THE AREA AND OUTFLOW
BOUNDARIES FROM PREVIOUS CONVECTION WILL RESULT IN ISOLATED TO
SCATTERED THUNDERSTORMS. SOMEWHAT SHALLOW MOISTURE ASSOCIATED WITH
THE UPPER-RIDGING SHOULD HELP TO LIMIT COVERAGE. DAMAGING WIND AND
HAIL WILL BE A THREAT WITH THE THUNDERSTORMS THIS AFTERNOON AND
EVENING.
THE THREAT OF THUNDERSTORMS WILL CONTINUE TONIGHT MAINLY BECAUSE
OF OUTFLOW BOUNDARY INTERACTION EARLY...ALONG WITH UPPER-LEVEL
LIFT LATE AHEAD OF A MID-LEVEL SHORTWAVE TROUGH. KEPT CHANCE POPS
THROUGH THE NIGHT. THE TEMPERATURE GUIDANCE WAS CLOSE TONIGHT
WITH LOWS IN THE MID AND UPPER 70S.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
A COLD FRONT WILL BE OFF TO THE WEST OF THE AREA THROUGH MUCH OF
THE DAY SATURDAY. PW VALUES WILL BE AROUND 2.0 SO LOCALLY HEAVY
RAINS WILL BE ASSOCIATED WITH THUNDERSTORMS. HIGHS WILL BE NEAR
NORMAL SATURDAY WITH THE MERCURY RANGING FROM 90 TO 95 DEGREES.
COLD FRONT WILL PUSH THROUGH THE AREA SATURDAY NIGHT. EXPECT
WIDESPREAD CONVECTION AS UPPER LEVEL SUPPORT VIA A SERIES OF SHORT
WAVES AND INCREASED INSTABILITY. SATURDAY NIGHT LOWS WILL RANGE
FROM THE MID 60S WEST TO LOWER 70S EAST AS CONVECTION COMES TO AN
END BEHIND THE COLD FRONT.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
MODELS CONTINUE TO BE IN GOOD AGREEMENT KEEPING THE UPPER LEVEL
TROUGH ACROSS THE EASTERN STATES SUNDAY THEN SHIFTING OFF THE
COAST BY THE MIDDLE OF NEXT WEEK. SURFACE HIGH PRESSURE WILL USHER
IN DRIER MORE STABLE AIR BEGINNING SUNDAY AND CONTINUING THROUGH
MONDAY. INCREASING MOISTURE AND INSTABILITY TUESDAY THROUGH
THURSDAY WILL INCREASE THE CHANCE FOR AFTERNOON/EVENING
CONVECTION. HIGHS WILL BE IN THE UPPER 80S SUNDAY...AROUND 90
MONDAY...AND 90 TO 95 TUESDAY THROUGH THURSDAY.
&&
.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
VFR CONDITIONS ARE EXPECTED FOR MUCH OF THE TAF PERIOD...BUT
THERE WILL BE A THREAT OF THUNDERSTORMS.
SUPPORT FOR THUNDERSTORMS WILL BE MAINLY CONVERGENCE INTO A HEAT
TROUGH AND POSSIBLE OUTFLOW BOUNDARIES FROM PREVIOUS CONVECTION.
SOMEWHAT SHALLOW MOISTURE ASSOCIATED WITH THE UPPER-RIDGING
SHOULD LIMIT COVERAGE. THE HRRR AND ARW DISPLAY ISOLATED TO
SCATTERED COVERAGE. THE SPC WRF HAS THE GREATEST THUNDERSTORM
COVERAGE AROUND 800 PM. A THREAT OF THUNDERSTORMS WILL CONTINUE
TONIGHT MAINLY BECAUSE OF OUTFLOW BOUNDARY INTERACTION EARLY. THE
MODELS ALSO INDICATE UPPER-LEVEL LIFT LATE AHEAD OF A MID-LEVEL
SHORTWAVE TROUGH. THERE WILL BE A THUNDERSTORM CHANCE THROUGH THE
NIGHT DESPITE NOCTURNAL COOLING. UNCERTAINTY WAS TOO HIGH TO
FORECAST THUNDERSTORMS EXPLICITLY IN THE TAFS AT ISSUANCE
TIME...BUT WE DID INCLUDE A VICINITY MENTION DURING THE MORE
LIKELY TIME OF CONVECTION.
THE THREAT OF FOG IS LOW OVERNIGHT BECAUSE OF CONTINUED
INSTABILITY AND LOW-LEVEL WINDS.
EXTENDED AVIATION OUTLOOK...WIDESPREAD RESTRICTIONS IN SHOWERS
AND THUNDERSTORMS MAY OCCUR SATURDAY EVENING AND SATURDAY NIGHT
ASSOCIATED WITH A COLD FRONT MOVING INTO THE AREA.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
208 PM EDT FRI JUN 26 2015
.SYNOPSIS...
THUNDERSTORMS WILL BE SCATTERED WELL AHEAD OF A COLD FRONT
THROUGH TONIGHT. THUNDERSTORM COVERAGE WILL INCREASE FOR SATURDAY
AS THE FRONT GETS CLOSER TO THE AREA. THE FRONT WILL CROSS THE
AREA SATURDAY NIGHT WITH DRY CONDITIONS AND TEMPERATURES NEAR
NORMAL ARRIVING EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
IT IS ANOTHER HOT AFTERNOON. UPPER-LEVEL RIDGING OVER THE FORECAST
AREA HAS HELPED PUSH TEMPERATURES TO AROUND 100 WITH HEAT INDEX
VALUES NEAR 105.
CONVERGENCE INTO THE HEAT TROUGH OVER THE AREA AND OUTFLOW
BOUNDARIES FROM PREVIOUS CONVECTION WILL RESULT IN THUNDERSTORMS.
SOMEWHAT SHALLOW MOISTURE ASSOCIATED WITH THE UPPER-RIDGING SHOULD
LIMIT COVERAGE. THE HRRR AND ARW DISPLAY ISOLATED TO SCATTERED
COVERAGE. THE SPC WRF HAS THE GREATEST THUNDERSTORM COVERAGE
AROUND 800 PM. A THREAT OF THUNDERSTORMS WILL CONTINUE TONIGHT
MAINLY BECAUSE OF OUTFLOW BOUNDARY INTERACTION EARLY. THE MODELS
ALSO INDICATE UPPER-LEVEL LIFT LATE AHEAD OF A MID-LEVEL SHORTWAVE
TROUGH. WE KEPT CHANCE POPS THROUGH THE NIGHT.
STRONG INSTABILITY HAS DEVELOPED. MIXED-LAYER CAPE WAS ABOVE
3000 J/KG OVER PART OF THE FORECAST AREA EARLY THIS AFTERNOON. THE
LATEST LAPS SOUNDINGS HAD CONSIDERABLE CAPE IN THE HAIL GROWTH
AREA. DAMAGING WIND AND HAIL WILL BE A THREAT WITH THE
THUNDERSTORMS THIS AFTERNOON AND EVENING.
THE TEMPERATURE GUIDANCE WAS CLOSE TONIGHT WITH LOWS IN THE MID
AND UPPER 70S.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
COLD FRONT WILL PUSH THROUGH THE AREA SATURDAY NIGHT. EXPECT
WIDESPREAD CONVECTION AS UPPER LEVEL SUPPORT VIA A SERIES OF
SHORT WAVES AND INCREASED INSTABILITY. PW VALUES WILL BE AROUND
2.O SO LOCALLY HEAVY RAINS WILL BE ASSOCIATED WITH THUNDERSTORMS.
HIGHS WILL BE NEAR NORMAL SATURDAY WITH THE MERCURY RANGING FROM
90 TO 95 DEGREES. SATURDAY NIGHT LOWS WILL RANGE FROM THE MID 60S
WEST TO LOWER 70S EAST AS CONVECTION COMES TO AN END BEHIND THE
COLD FRONT.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
MODELS CONTINUE TO BE IN GOOD AGREEMENT KEEPING THE UPPER LEVEL
TROUGH ACROSS THE EASTERN STATES SUNDAY THEN SHIFTING OFF THE
COAST BY THE MIDDLE OF NEXT WEEK. SURFACE HIGH PRESSURE WILL USHER
IN DRIER MORE STABLE AIR BEGINNING SUNDAY AND CONTINUING THROUGH
MONDAY. INCREASING MOISTURE AND INSTABILITY TUESDAY THROUGH
THURSDAY WILL INCREASE THE CHANCE FOR AFTERNOON/EVENING
CONVECTION. HIGHS WILL BE IN THE UPPER 80S SUNDAY...AROUND 90
MONDAY...AND 90 TO 95 TUESDAY THROUGH THURSDAY.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
VFR CONDITIONS ARE EXPECTED FOR MUCH OF THE TAF PERIOD...BUT
THERE WILL BE A THREAT OF THUNDERSTORMS.
SUPPORT FOR THUNDERSTORMS WILL BE MAINLY CONVERGENCE INTO A HEAT
TROUGH AND POSSIBLE OUTFLOW BOUNDARIES FROM PREVIOUS CONVECTION.
SOMEWHAT SHALLOW MOISTURE ASSOCIATED WITH THE UPPER-RIDGING
SHOULD LIMIT COVERAGE. THE HRRR AND ARW DISPLAY ISOLATED TO
SCATTERED COVERAGE. THE SPC WRF HAS THE GREATEST THUNDERSTORM
COVERAGE AROUND 800 PM. A THREAT OF THUNDERSTORMS WILL CONTINUE
TONIGHT MAINLY BECAUSE OF OUTFLOW BOUNDARY INTERACTION EARLY. THE
MODELS ALSO INDICATE UPPER-LEVEL LIFT LATE AHEAD OF A MID-LEVEL
SHORTWAVE TROUGH. THERE WILL BE A THUNDERSTORM CHANCE THROUGH THE
NIGHT DESPITE NOCTURNAL COOLING. UNCERTAINTY WAS TOO HIGH TO
FORECAST THUNDERSTORMS EXPLICITLY IN THE TAFS AT ISSUANCE
TIME...BUT WE DID INCLUDE A VICINITY MENTION DURING THE MORE
LIKELY TIME OF CONVECTION.
STRONG INSTABILITY WITH CONSIDERABLE CAPE IN THE HAIL GROWTH AREA
INDICATES A THREAT OF STRONG WIND AND HAIL WITH ANY THUNDERSTORMS
THIS AFTERNOON INTO THE EVENING.
OTHER THAN IN SHOWERS...THE THREAT OF FOG IS LOW OVERNIGHT BECAUSE
OF CONTINUED INSTABILITY.
EXTENDED AVIATION OUTLOOK...WIDESPREAD RESTRICTIONS IN SHOWERS
AND THUNDERSTORMS MAY OCCUR SATURDAY AND SATURDAY NIGHT ASSOCIATED
WITH A COLD FRONT MOVING INTO THE AREA.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
99
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1238 PM EDT FRI JUN 26 2015
.SYNOPSIS...
THUNDERSTORMS WILL BE SCATTERED WELL AHEAD OF A
COLD FRONT THROUGH TONIGHT. THUNDERSTORM COVERAGE WILL INCREASE
FOR SATURDAY AS THE FRONT GETS CLOSER TO THE AREA. THE FRONT WILL
CROSS THE AREA SATURDAY NIGHT WITH DRY CONDITIONS AND TEMPERATURES
NEAR NORMAL ARRIVING EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
IT IS ANOTHER HOT AFTERNOON. UPPER-LEVEL RIDGING OVER THE FORECAST
AREA HAS HELPED PUSH TEMPERATURES TO AROUND 100.
CONVERGENCE INTO THE HEAT TROUGH OVER THE AREA AND OUTFLOW
BOUNDARIES FROM PREVIOUS CONVECTION...MAINLY IN THE NORTH PART
WILL RESULT IN THUNDERSTORMS. SOMEWHAT SHALLOW MOISTURE
ASSOCIATED WITH THE UPPER-RIDGING SHOULD LIMIT COVERAGE. THE HRRR
AND ARW DISPLAY ISOLATED TO SCATTERED COVERAGE MAINLY IN THE
NORTH PART. THE SPC WRF HAS THE GREATEST THUNDERSTORM COVERAGE
AROUND 800 PM. A THREAT OF THUNDERSTORMS WILL CONTINUE TONIGHT
MAINLY BECAUSE OF OUTFLOW BOUNDARY INTERACTION EARLY. THE MODELS
ALSO INDICATE UPPER-LEVEL LIFT LATE AHEAD OF A MID-LEVEL SHORTWAVE
TROUGH. WE KEPT CHANCE POPS THROUGH THE NIGHT.
STRONG INSTABILITY HAS DEVELOPED. MIXED-LAYER CAPE WAS ABOVE
3000 J/KG OVER PART OF THE FORECAST AREA EARLY THIS AFTERNOON. THE
LATEST LAPS SOUNDING HAD CONSIDERABLE CAPE IN THE HAIL GROWTH
AREA. DAMAGING WIND AND HAIL WILL BE A THREAT WITH THE
THUNDERSTORMS THIS AFTERNOON AND EVENING.
THE TEMPERATURE GUIDANCE WAS CLOSE TONIGHT WITH LOWS IN THE MID
AND UPPER 70S.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
COLD FRONT WILL PUSH THROUGH THE AREA SATURDAY NIGHT. EXPECT
WIDESPREAD CONVECTION AS UPPER LEVEL SUPPORT VIA A SERIES OF
SHORT WAVES AND INCREASED INSTABILITY. PW VALUES WILL BE AROUND
2.O SO LOCALLY HEAVY RAINS WILL BE ASSOCIATED WITH THUNDERSTORMS.
HIGHS WILL BE NEAR NORMAL SATURDAY WITH THE MERCURY RANGING FROM
90 TO 95 DEGREES. SATURDAY NIGHT LOWS WILL RANGE FROM THE MID 60S
WEST TO LOWER 70S EAST AS CONVECTION COMES TO AN END BEHIND THE
COLD FRONT.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
MODELS CONTINUE TO BE IN GOOD AGREEMENT KEEPING THE UPPER LEVEL
TROUGH ACROSS THE EASTERN STATES SUNDAY THEN SHIFTING OFF THE
COAST BY THE MIDDLE OF NEXT WEEK. SURFACE HIGH PRESSURE WILL USHER
IN DRIER MORE STABLE AIR BEGINNING SUNDAY AND CONTINUING THROUGH
MONDAY. INCREASING MOISTURE AND INSTABILITY TUESDAY THROUGH
THURSDAY WILL INCREASE THE CHANCE FOR AFTERNOON/EVENING
CONVECTION. HIGHS WILL BE IN THE UPPER 80S SUNDAY...AROUND 90
MONDAY...AND 90 TO 95 TUESDAY THROUGH THURSDAY.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
VFR CONDITIONS ARE EXPECTED FOR MUCH OF THE TAF PERIOD...BUT
THERE WILL BE A THREAT OF THUNDERSTORMS.
SUPPORT FOR THUNDERSTORMS WILL BE MAINLY CONVERGENCE INTO A HEAT
TROUGH AND POSSIBLE OUTFLOW BOUNDARIES FROM PREVIOUS CONVECTION.
SOMEWHAT SHALLOW MOISTURE ASSOCIATED WITH THE UPPER-RIDGING
SHOULD LIMIT COVERAGE. THE HRRR AND ARW DISPLAY ISOLATED TO
SCATTERED COVERAGE. THE SPC WRF HAS THE GREATEST THUNDERSTORM
COVERAGE AROUND 800 PM. A THREAT OF THUNDERSTORMS WILL CONTINUE
TONIGHT MAINLY BECAUSE OF OUTFLOW BOUNDARY INTERACTION EARLY. THE
MODELS ALSO INDICATE UPPER-LEVEL LIFT LATE AHEAD OF A MID-LEVEL
SHORTWAVE TROUGH. THERE WILL BE A THUNDERSTORM CHANCE THROUGH THE
NIGHT DESPITE NOCTURNAL COOLING. UNCERTAINTY WAS TOO HIGH TO
FORECAST THUNDERSTORMS EXPLICITLY IN THE TAFS AT ISSUANCE
TIME...BUT WE DID INCLUDE A VICINITY MENTION DURING THE MORE
LIKELY TIME OF CONVECTION.
STRONG INSTABILITY WITH CONSIDERABLE CAPE IN THE HAIL GROWTH AREA
INDICATES A THREAT OF STRONG WIND AND HAIL WITH ANY THUNDERSTORMS
THIS AFTERNOON INTO THE EVENING.
OTHER THAN IN SHOWERS...THE THREAT OF FOG IS LOW OVERNIGHT BECAUSE
OF CONTINUED INSTABILITY.
EXTENDED AVIATION OUTLOOK...WIDESPREAD RESTRICTIONS IN SHOWERS
AND THUNDERSTORMS MAY OCCUR SATURDAY AND SATURDAY NIGHT ASSOCIATED
WITH A COLD FRONT MOVING INTO THE AREA.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
99
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1231 PM EDT FRI JUN 26 2015
.SYNOPSIS...THUNDERSTORMS WILL BE SCATTERED WELL AHEAD OF A
COLD FRONT THROUGH TONIGHT. THUNDERSTORM COVERAGE WILL INCREASE
FOR SATURDAY AS THE FRONT GETS CLOSER TO THE AREA. THE FRONT WILL
CROSS THE AREA SATURDAY NIGHT WITH DRY CONDITIONS AND TEMPERATURES
NEAR NORMAL ARRIVING EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
IT IS ANOTHER HOT AFTERNOON. UPPER-LEVEL RIDGING OVER THE FORECAST
AREA HAS HELPED PUSH TEMPERATURES TO AROUND 100.
CONVERGENCE INTO THE HEAT TROUGH OVER THE AREA AND OUTFLOW
BOUNDARIES FROM PREVIOUS CONVECTION...MAINLY IN THE NORTH PART
WILL RESULT IN THUNDERSTORMS. SOMEWHAT SHALLOW MOISTURE
ASSOCIATED WITH THE UPPER-RIDGING SHOULD LIMIT COVERAGE. THE HRRR
AND ARW DISPLAY ISOLATED TO SCATTERED COVERAGE MAINLY IN THE
NORTH PART. THE SPC WRF HAS THE GREATEST THUNDERSTORM COVERAGE
AROUND 800 PM. A THREAT OF THUNDERSTORMS WILL CONTINUE TONIGHT
MAINLY BECAUSE OF OUTFLOW BOUNDARY INTERACTION EARLY. THE MODELS
ALSO INDICATE UPPER-LEVEL LIFT LATE AHEAD OF A MID-LEVEL SHORTWAVE
TROUGH. WE KEPT CHANCE POPS THROUGH THE NIGHT.
STRONG INSTABILITY HAS DEVELOPED. MIXED-LAYER CAPE WAS ABOVE
3000 J/KG OVER PART OF THE FORECAST AREA EARLY THIS AFTERNOON. THE
LATEST LAPS SOUNDING HAD CONSIDERABLE CAPE IN THE HAIL GROWTH
AREA. DAMAGING WIND AND HAIL WILL BE A THREAT WITH THE
THUNDERSTORMS THIS AFTERNOON AND EVENING.
THE TEMPERATURE GUIDANCE WAS CLOSE TONIGHT WITH LOWS IN THE MID
AND UPPER 70S.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
AS THE UPPER TROUGH DEEPENS OVER THE EASTERN STATES...A SURFACE
LOW PRESSURE SYSTEM WILL CROSS THE UPPER MISSISSIPPI RIVER VALLEY
TO THE GREAT LAKES REGION. ITS ASSOCIATED COLD FRONT WILL CROSS
OUR AREA SATURDAY NIGHT. EXPECT WIDESPREAD CONVECTION SATURDAY AS
A COUPLE OF SHORT WAVES MOVE THROUGH AND INSTABILITY INCREASES. PW
VALUES WILL BE AROUND 2.O SO LOCALLY HEAVY RAINS WILL BE
ASSOCIATED WITH THUNDERSTORMS. KEPT HIGHS IN THE UPPER 80S AND
LOWER 90S ON SATURDAY...WHICH ARE A FEW DEGREES BELOW GUIDANCE
CONSENSUS...GIVEN CLOUDS AND PRECIP. LOWS SATURDAY NIGHT ARE
EXPECTED TO RANGE FROM THE MID 60S WEST TO LOWER 70S EAST AS
CONVECTION COMES TO AN END BEHIND THE COLD FRONT.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
GFS AND ECMWF IN GOOD AGREEMENT KEEPING THE UPPER LEVEL TROUGH
ACROSS THE EASTERN STATES SUNDAY THEN SHIFTING OFF THE COAST BY
THE MIDDLE OF NEXT WEEK. SURFACE HIGH PRESSURE WILL USHER IN DRIER
MORE STABLE AIR BEGINNING SUNDAY AND CONTINUING THROUGH MONDAY.
MOISTURE AND INSTABILITY BEGIN TO INCREASE AGAIN TUESDAY AND
WEDNESDAY.
HIGHS IN THE UPPER 80S SUNDAY...AROUND 90 MONDAY...AND 90 TO 95
TUESDAY AND WEDNESDAY.
&&
.AVIATION /16Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS ARE EXPECTED FOR MUCH OF THE TAF PERIOD...BUT
THERE WILL BE A THREAT OF THUNDERSTORMS.
SUPPORT FOR THUNDERSTORMS WILL BE MAINLY CONVERGENCE INTO A HEAT
TROUGH AND POSSIBLE OUTFLOW BOUNDARIES FROM PREVIOUS CONVECTION.
SOMEWHAT SHALLOW MOISTURE ASSOCIATED WITH THE UPPER-RIDGING
SHOULD LIMIT COVERAGE. THE HRRR AND ARW DISPLAY ISOLATED TO
SCATTERED COVERAGE. THE SPC WRF HAS THE GREATEST THUNDERSTORM
COVERAGE AROUND 800 PM. A THREAT OF THUNDERSTORMS WILL CONTINUE
TONIGHT MAINLY BECAUSE OF OUTFLOW BOUNDARY INTERACTION EARLY. THE
MODELS ALSO INDICATE UPPER-LEVEL LIFT LATE AHEAD OF A MID-LEVEL
SHORTWAVE TROUGH. THERE WILL BE A THUNDERSTORM CHANCE THROUGH THE
NIGHT DESPITE NOCTURNAL COOLING. UNCERTAINTY WAS TOO HIGH TO
FORECAST THUNDERSTORMS EXPLICITLY IN THE TAFS AT ISSUANCE
TIME...BUT WE DID INCLUDE A VICINITY MENTION DURING THE MORE
LIKELY TIME OF CONVECTION.
STRONG INSTABILITY WITH CONSIDERABLE CAPE IN THE HAIL GROWTH AREA
INDICATES A THREAT OF STRONG WIND AND HAIL WITH ANY THUNDERSTORMS
THIS AFTERNOON INTO THE EVENING.
OTHER THAN IN SHOWERS...THE THREAT OF FOG IS LOW OVERNIGHT BECAUSE
OF CONTINUED INSTABILITY.
EXTENDED AVIATION OUTLOOK...WIDESPREAD RESTRICTIONS IN SHOWERS
AND THUNDERSTORMS MAY OCCUR SATURDAY AND SATURDAY NIGHT ASSOCIATED
WITH A COLD FRONT MOVING INTO THE AREA.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
99
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1259 PM CDT FRI JUN 26 2015
.UPDATE...
ISSUED AT 1045 AM CDT FRI JUN 26 2015
WILL UPDATE THE FORECAST TO EXPAND THE FLASH FLOOD WATCH FURTHER
NORTH THIS AFTERNOON AND INTO MID EVENING UNTIL 10 PM TO INCLUDE
ALL OF OUR CWA EXCEPT FOR KNOX...STARK AND MARSHALL COUNTIES.
SHOWERS AND THUNDERSTORMS HAVE SPREAD SLOWLY AS FAR NORTH AS
PEORIA BY LATE MORNING WITH HEAVIEST RAINS OVER 1 INCH ALONG A
LEWISTOWN TO PEKIN TO BLOOMINGTON TO DANVILLE LINE. A QUASI
STATIONARY BOUNDARY WAS NEAR I-72 AND EXTENDED TO 1013 MB SURFACE
LOW PRESSURE OVER NE MO BETWEEN KIRKSVILLE AND QUINCY. ANOTHER
1013 MB SURFACE LOW PRESSURE WAS OVER SOUTHEAST MO. HRRR MODEL
HANDLING THIS CONVECTION WELL AND USED THIS MODEL FOR FORECAST
THIS AFTERNOON AND EVENING. SURFACE LOW PRESSURE TO QUICKLY DEEPEN
TO 1006 MB AS IT TRACKS TO NEAR TERRE HAUTE INDIANA BY SUNSET.
HEAVIEST RAINS TO FALL ALONG AND NORTH OF THE LOW PRESSURE TRACK
AND FRONTAL BOUNDARY NORTH OF I-70 WHERE ADDITIONAL 1 INCH OF RAIN
EXPECTED WITH LOCALLY 1 TO 2 MORE INCHES OF RAIN POSSIBLE FROM
I-72 NORTH. SPC ALSO HAS SLIGHT RISK OF SEVERE STORMS THIS
AFTERNOON OVER FAR SE IL SE OF A OLNEY TO ROBINSON LINE FOR 15%
RISK OF DAMAGING WIND GUSTS AND LARGE HAIL AND 2% RISK OF
TORNADOES. ENHANCED SLIGHT RISK WAS SE OF LAWERNCE COUNTY AND
CENTERED OVER KY AND MID/NW TN. HIGHS MOSTLY IN THE MID 70S OVER
CENTRAL IL WITH LOWER 80S IN FAR SOUTHEAST IL AND HUMID WITH
DEWPOINTS IN THE MID 60S TO LOWER 70S.
&&
.SHORT TERM...(TODAY)
ISSUED AT 305 AM CDT FRI JUN 26 2015
08Z/3AM SURFACE ANALYSIS SHOWS LOW PRESSURE NEAR KANSAS CITY...WITH
STATIONARY FRONTAL BOUNDARY EXTENDING E/SE INTO FAR SOUTHERN
ILLINOIS. MCS THAT IMPACTED THE SE KILX CWA EARLIER THIS EVENING
HAS NOW TRACKED INTO CENTRAL/EASTERN KENTUCKY...WHILE A SECOND MCS
HAS DEVELOPED UPSTREAM OVER EASTERN KANSAS INTO WEST-CENTRAL
MISSOURI. THIS SECOND SYSTEM WILL CONTINUE TO TRACK E/SE ALONG THE
SYNOPTIC FRONT/OUTFLOW FROM PREVIOUS COMPLEX INTO SOUTHERN ILLINOIS
LATER THIS MORNING. FURTHER NORTH...STRATIFORM RAIN WITH A FEW
EMBEDDED THUNDERSTORMS WILL SPREAD INTO CENTRAL ILLINOIS FROM THE
WEST. DUE TO EXTENSIVE CLOUD COVER NORTH OF THE FRONT...WILL ONLY
MENTION ISOLATED THUNDER ALONG/NORTH OF THE I-72 CORRIDOR. FURTHER
SOUTH...WILL GO WITH PREDOMINANT THUNDER CLOSER TO THE BOUNDARY AND
THE MORE UNSTABLE AIRMASS ALONG/SOUTH OF I-70. LATEST DAY 1
CONVECTIVE OUTLOOK PLACES THE FAR SOUTHEAST CWA IN A SLIGHT RISK FOR
SEVERE...WITH DAMAGING WIND GUSTS AND LARGE HAIL BEING THE PRIMARY
THREATS LATER TODAY. HEAVIEST RAINFALL WILL ALSO BE FOCUSED ACROSS
THE SOUTHEAST WHERE 1 TO 1.5 INCHES WILL BE LIKELY.
.LONG TERM...(TONIGHT THROUGH THURSDAY)
ISSUED AT 305 AM CDT FRI JUN 26 2015
SHORT-WAVE TROUGH EVIDENT ON CURRENT WATER VAPOR IMAGERY OVER
EASTERN NEBRASKA/KANSAS WILL TRACK EASTWARD INTO INDIANA TONIGHT.
SHOWERS AND A FEW THUNDERSTORMS WILL CONTINUE ALONG/AHEAD OF THIS
FEATURE THIS EVENING...WITH RAIN CHANCES DIMINISHING FROM WEST TO
EAST AFTER MIDNIGHT. ONCE THE WAVE PASSES TO THE EAST AND THE
PERSISTENT FRONTAL BOUNDARY DRAPED ACROSS SOUTHERN ILLINOIS GETS A
GOOD PUSH SOUTHWARD...COOLER AND DRIER WEATHER WILL BE ON TAP FOR
SATURDAY. EVEN WITH MOSTLY SUNNY SKIES...BRISK NORTHERLY FLOW WILL
KEEP TEMPS SEVERAL DEGREES BELOW NORMAL FOR THIS TIME OF YEAR IN THE
MIDDLE TO UPPER 70S.
SYNOPTIC PATTERN THROUGHOUT THE EXTENDED WILL FEATURE A LARGE UPPER
RIDGE OVER THE ROCKIES AND A CORRESPONDING DOWNSTREAM TROUGH ACROSS
THE GREAT LAKES/MIDWEST. WITH THIS PATTERN REMAINING FIRMLY IN PLACE
THROUGH NEXT WEEK...A CONTINUATION OF BELOW NORMAL TEMPERATURES IS
ANTICIPATED ALONG WITH PERIODIC RAIN CHANCES. SEVERAL SHORT-WAVES
WILL DROP INTO THE REGION WITHIN THE BROAD NORTHWESTERLY FLOW
PATTERN...HOWEVER THE EXACT TIMING AND STRENGTH OF THESE FEATURES
WILL BE DIFFICULT TO DETERMINE THIS FAR OUT. BASED ON GFS/ECMWF
CONSENSUS...IT APPEARS TWO DISTINCT PERIODS OF ENHANCED RAIN CHANCES
ARE EMERGING. ONE LATE SUNDAY INTO MONDAY AND ANOTHER LATE TUESDAY
INTO WEDNESDAY. HAVE INCLUDED MENTIONABLE POPS DURING THOSE TIME
FRAMES...THEN HAVE GONE WITH A DRY FORECAST THE REST OF THE TIME.
NEITHER OF THESE TWO SYSTEMS WILL HAVE NEARLY AS MUCH MOISTURE TO
WORK WITH AS RECENT SYSTEMS...SO DESPITE POPS...RAINFALL AMOUNTS
WILL REMAIN LIGHT NEXT WEEK. MAIN STORY WILL THE UNSEASONABLY COOL
CONDITIONS...WITH HIGHS IN THE UPPER 70S AND LOWER 80S THROUGH THE
ENTIRE WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1255 PM CDT FRI JUN 26 2015
LARGE AREA OF SHOWERS AND ISOLATED THUNDERSTORMS OVER CENTRAL IL
WILL BRING IFR TO MVFR VISIBILITIES AND CEILINGS THIS AFTERNOON
AND GENERALLY LOWEST ALONG I-74 AIRPORTS OF PIA...BMI AND CMI
WHERE CEILINGS AS LOW AS AROUND 500 FT. RAIN SHOWERS TO GRADUALLY
DIMINISH FROM WEST TO EAST DURING MID/LATE EVENING AS 1012 MB LOW
PRESSURE OVER NE MO DEEPENS TO 1005 MB AS IT TRACKS TO SOUTH
CENTRAL INDIANA BY MIDNIGHT TONIGHT. MVFR CEILINGS TO CONTINUE
TONIGHT INTO SAT MORNING AND COULD BE BELOW 1K FT OVER EASTERN TAF
SITES TONIGHT. LOW CLOUDS SHOULD SCATTER OUT FROM NW TO SE BETWEEN
14-18Z SAT HAPPENING FIRST AT PIA AND LAST AT CMI. SSE WINDS NEAR
10 KTS OR LESS AT SPI AND DEC SHOULD VEER NE NEXT FEW HOURS AND NE
WINDS TO INCREASE TO 10-15 KTS ACROSS CENTRAL IL LATER THE
AFTERNOON AND EVENING. NE WINDS TO VEER NORTHERLY DURING TONIGHT
INTO SAT MORNING AS LOW PRESSURE DEEPENS AND PULLS AWAY FROM IL.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 10 PM CDT THIS EVENING FOR ILZ029-031-
036>038-040>057-061>063-066>068-071>073.
&&
$$
UPDATE...07
SHORT TERM...BARNES
LONG TERM...BARNES
AVIATION...07
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
607 PM EDT FRI JUN 26 2015
.SYNOPSIS...
UNSEASONABLY DEEP LOW PRESSURE WILL MOVE THROUGH THE REGION ON
SATURDAY...WITH MUCH COLDER AND WINDY CONDITIONS TO END THE
WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
NO MAJOR CHANGES WERE COMPLETED FOR THE EARLY EVE UPDATE ALTHOUGH
THE THUNDER MENTION WAS REMOVED GIVEN A PROGGED LACK OF INSTABILITY.
PREVIOUS...
THE UPPER TROUGH OVER THE WESTERN GREAT LAKES WILL CONTINUE TO
DEEPEN AS IT PIVOTS EASTWARD TOWARD THE OHIO VALLEY OVERNIGHT.
THIS AND A COUPLED JET WILL HELP TO INTENSIFY THE SURFACE LOW AS
IT MOVES TOWARD NORTHERN OHIO BY SATURDAY MORNING. TONIGHT...THE
WARM FRONT WILL BE LIFTED ACROSS THE REGION. THE MODELS HAVE
STRUGGLED TO RESOLVE THIS INITIAL PRECIPITATION WITH THE
BOUNDARY...BUT SO FAR THE RUC AND THE HRRR HAVE HANDLED IT
BEST...SO LOW CHANCE POPS WERE MAINTAIN AND THEN RAMPED UP AS THE
LOW APPROACHES.
OVERNIGHT...STRONG ISENTROPIC LIFT AND DEEP MOISTURE WILL PROVIDE
FOR A PROLONGED PERIOD OF RAINFALL...AT LEAST UNTIL DRY AIR WRAPS
INTO THE MID LEVELS OF THE OCCLUDING LOW LATER ON SATURDAY
MORNING.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
RAIN WILL BE ONGOING AT THE START OF THIS PERIOD...WITH SURFACE LOW
POSITIONED IN WESTERN OHIO. OVERALL SURFACE LOW PROGRESSION AND
DEEPENING IS FORECAST TO SLOW AS THE MID LEVEL LOW CLOSES OVER
NORTHEAST OHIO. THE MATURING SYSTEM IS THEN PROJECTED TO DRIFT
NORTHEASTWARD THROUGH SUNDAY.
TAIL END OF RAIN SHIELD WILL THUS PROGRESS NORTHEASTWARD WITH THE
MID LEVEL DRY SLOT THROUGH THE MORNING. THE TIMING OF THAT FEATURE
WITH WARM FRONT POSITIONING AND PROLONGED MOISTURE CONVERGENCE
NORTH AND EAST OF THE MID LEVEL LOW WILL DETERMINE WHERE THE
HEAVIEST RAINFALL OCCURS. AT MOMENT...AREAS NORTH OF
PITTSBURGH...ESPECIALLY THOSE ALONG AND NORTH OF I-80...ARE
PROJECTED FOR THE HIGHER TOTALS AROUND...AND IN EXCESS OF 2
INCHES. GIVEN THE RECENT WET PERIOD...THE COLLABORATED FLOOD WATCH
HAS BEEN CONTINUED WITH A GENERAL 1 TO 2 INCHES ANTICIPATED
ELSEWHERE.
THERE IS AN INTERESTING CONDITIONAL COMPONENT TO THE SATURDAY
AFTERNOON/EVENING FORECAST. GIVEN THE STRENGTH AND CUTOFF NATURE
OF THIS SYSTEM...DEEP LAYER SPEED AND DIRECTIONAL SHEAR WILL BE
DANGEROUSLY HIGH...WHILE BOUNDARY LAYER VALUES ESCALATE IN
VICINITY OF THE AFOREMENTIONED WARM FRONT. SHOULD SUFFICIENT
DESTABILIZATION OCCUR UNDER THE ENCROACHING DRY SLOT...THEN THE
POTENTIAL FOR SEVERE WEATHER WILL ESCALATE. NO ACTION WAS TAKEN
JUST YET...BUT THIS POTENTIAL WILL BE CLOSELY MONITORED.
PERIODIC SHOWER POTENTIAL AND COOLER TEMPERATURES CAN BE EXPECTED
THEREAFTER AS AN AMPLIFIED GREAT LAKE-TO-GULF OF MEXICO UPPER
TROUGH DEVELOPS FOR THE START OF THE NEW WEEK.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
LONGER RANGE MODEL GUIDANCE FAVORS DRASTICALLY INCREASED RIDGING
IN THE WEST WITH DOWNSTREAM DEEPENING TROUGHING ACROSS THE GREAT
LAKES. THIS WILL LIKELY KEEP THINGS FAIRLY ACTIVE AND WET OVER THE
CWA...WITH TEMPERATURES LIKELY TO REMAIN A BIT BELOW NORMAL. MODEL
TIMING OF INDIVIDUAL SHORT WAVES IS EXCEEDINGLY SUSPECT AT THIS
JUNCTURE...HOWEVER MONDAY NIGHT INTO TUESDAY PROBABLY SEES THE
BEST SHOT AT WIDESPREAD RAIN SHOWERS ACROSS THE AREA. FRIES
&&
.AVIATION /22Z FRIDAY THROUGH WEDNESDAY/...
WARM FRONT SHOULD SLOWLY LIFT ACROSS THE REGION OVERNIGHT. HAVE
CONTINUED VCTS AT ZZV WITH THUNDERSTORMS CONTINUING ACROSS CENTRAL
OHIO...BUT WITH AMOUNT OF CLOUD COVER ACROSS EASTERN OHIO INTO
WESTERN PENNSYLVANIA...THINK THAT THUNDERSTORM COVERAGE SHOULD
REMAIN CONTAINED TO CENTRAL WEST VIRGINIA. MAINLY MVFR CIG
RESTRICTIONS ARE ANTICIPATED UNTIL THE LOW APPROACHES OVERNIGHT
AND STRATIFORM RAINFALL APPROACHES AT WHICH POINT MOST SITES
SHOULD EXPERIENCE A PERIOD OF IFR CIGS AND/OR VISIBILITY.
CONDITIONS MAY IMPROVE TOWARD MORNING AS THE DRY SLOT APPROACHES.
STARTED AN UPWARD TREND BUT DID NOT GO BACK TO VFR AT THIS TIME.
THUNDERSTORMS MAY BE POSSIBLE TOMORROW AFTERNOON IF WE CAN SCATTER
OUT THE CLOUDS IN THE DRY SLOT.
.OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
RESTRICTIONS ARE LIKELY THROUGH THE REST OF THE WEEKEND WITH
PASSAGE OF A STRONG LOW PRESSURE SYSTEM. AN APPROACHING COLD FRONT
MAY CAUSE POSSIBLE RESTRICTIONS WITH RAIN MONDAY AND TUESDAY.
&&
.HYDROLOGY...
A RAPIDLY DEEPENING SYSTEM WILL DROP HEAVY RAIN ONTO THE AREA
FRIDAY NIGHT INTO SATURDAY. AT THIS TIME...MOST OF THE AREA SEEMS
LIKELY TO RECEIVE 1 TO 1.75 INCHES THROUGH THE PERIOD...HOWEVER
SOME AREAS NORTH OF I-80 MAY SEE IN EXCESS OF 2 INCHES. LOCALIZED
URBAN AND SMALL STREAM FLOODING WILL BE THE MOST LIKELY
PROBLEM...HOWEVER AS THE TRACK OF THE SYSTEM IS PINNED DOWN MORE
CLOSELY...AND EXACT BASINS WHICH WILL RECEIVE THE MOST RAINFALL
ARE DETERMINED...A MORE ADEQUATE DETERMINATION OF THE RISK OF
RIVER FLOODING CAN BE MADE.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...FLOOD WATCH THROUGH SATURDAY AFTERNOON FOR MDZ001.
OH...FLOOD WATCH THROUGH SATURDAY AFTERNOON FOR OHZ039>041-048>050-
057>059-068-069.
PA...FLOOD WATCH THROUGH SATURDAY AFTERNOON FOR PAZ014-020>023-029-
031-073>076.
FLOOD WATCH FROM 11 PM EDT THIS EVENING THROUGH LATE SATURDAY
NIGHT FOR PAZ007>009-013-015-016.
WV...FLOOD WATCH THROUGH SATURDAY AFTERNOON FOR WVZ001>004-012-
021>023-041.
&&
$$
15/33
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
312 PM EDT FRI JUN 26 2015
.SYNOPSIS...
UNSEASONABLY DEEP LOW PRESSURE WILL MOVE THROUGH THE REGION ON
SATURDAY...WITH MUCH COLDER AND WINDY CONDITIONS TO END THE
WEEKEND. UNSETTLED WEATHER REMAINS THROUGH MUCH OF THE UPCOMING
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPPER TROUGH OVER THE WESTERN GREAT LAKES WILL CONTINUE TO DEEPEN
AS IT PIVOTS EASTWARD TOWARD THE OHIO VALLEY OVERNIGHT. THIS AND
A COUPLED JET WILL HELP TO INTENSIFY THE SURFACE LOW AS IT MOVES
TOWARD NORTHERN OHIO BY SATURDAY MORNING. TONIGHT...THE WARM FRONT
WILL BE LIFTED ACROSS THE REGION. THE MODELS HAVE STRUGGLED TO
RESOLVE THIS INITIAL PRECIPITATION WITH THE BOUNDARY...BUT SO FAR
THE RUC AND THE HRRR HAVE HANDLED IT BEST...SO LOW CHANCE POPS
WERE MAINTAIN AND THEN RAMPED UP AS THE LOW APPROACHES.
OVERNIGHT...STRONG ISENTROPIC LIFT AND DEEP MOISTURE WILL PROVIDE
FOR A PROLONGED PERIOD OF RAINFALL. PWAT VALUES WILL APPROACH 1.75
TO 2.00 INCHES...WHICH SHOULD ALLOW FOR DECENT RAINFALL RATES AT
LEAST UNTIL MORNING BEFORE DRY AIR WRAPS AROUND THE OCCLUDING LOW
PRESSURE. WITH AMPLE CLOUD COVER AND PRECIPITATION...DO NOT SEE
TEMPERATURES DOING MUCH OVERNIGHT. SO...LOWS WERE KEPT ABOVE
SEASONAL AVERAGES...IN THE 60`S.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/... HEAVY RAIN EVENT WILL BE
ONGOING AT THE START OF THIS PERIOD...WITH SURFACE LOW POSITIONED IN
WESTERN OHIO. CONTINUE TO BE IMPRESSED WITH THIS SYSTEM...AS IT
COMBINES WINTERTIME SYNOPTIC FORCING WITH SUMMERTIME MOISTURE.
OVERALL SURFACE LOW PROGRESSION AND DEEPENING WILL SLOW WITH TIME AS
H500 PATTERN CLOSES OFF AND SYSTEM BECOMES VERTICALLY STACKED ACROSS
NORTHEAST OHIO SATURDAY NIGHT. THE UPPER LOW WILL THEN DRIFT
NORTHEASTWARD OVER THE EASTERN GREAT LAKES THROUGH SUNDAY BEFORE
FINALLY PULLING AWAY SUNDAY NIGHT.
TAIL END OF HEAVY RAIN SHIELD WILL PROGRESS FROM SOUTHWEST TO
NORTHEAST DURING THE MORNING AS THE LONG-ADVERTISED DRY SLOT
DEVELOPS. THE TIMING AND POSITIONING OF THIS FEATURE WILL OF COURSE
ULTIMATELY DETERMINE WHERE THE HEAVIEST RAINFALL TOTALS OCCUR. FOR
NOW...IT APPEARS THAT AREAS ALONG AND NORTH OF I-80 WILL SEE THE
HIGHER TOTALS AS DRY SLOT MAY NOT BE ABLE TO FULLY DEVELOP IN THIS
REGION BEFORE COMMAHEAD PRECIP MOVES IN. THIS IS WHERE THE 2+ INCH
STORM TOTAL RAINFALL VALUES ARE MOST LIKELY. AREAS TO THE SOUTH
WILL STILL REACH THE 1-2 INCH RANGE AT LEAST WITH LOCALLY HIGHER
TOTALS. WHILE FLOODING ISSUES ARE NOT EXPECTED TO BE
WIDESPREAD...ENOUGH OF A THREAT REMAINS TO MAINTAIN THE GOING WATCH.
THERE IS AN INTERESTING CONDITIONAL COMPONENT TO THE SATURDAY
AFTERNOON/EVENING FORECAST. BUFKIT SOUNDINGS ARE SHOWING A FAIRLY
DECENT ENVIRONMENT THAT COULD FAVOR STRONG TO EVEN SEVERE
THUNDERSTORMS. BETWEEN 18Z SAT AND 00Z SUN...PROFILES SHOW
IMPRESSIVELY CURVED HODOGRAPHS IN THE DRY SLOT ACROSS SOUTHWEST PA
WITH DIRECTIONAL AND SPEED SHEAR. THE NAM HINTS AT THE DEVELOPMENT
OF A FAST-MOVING CONVECTIVE LINE AFTER 21Z. INSTABILITY IS THE
CRITICAL FACTOR. IF THE DRY SLOT DEVELOPS EARLY ENOUGH TO ALLOW FOR
GOOD DIABATIC HEATING...THE ENVIRONMENT COULD QUITE READILY SUPPORT
STRONG STORMS. CERTAINLY SOMETHING TO MONITOR.
A BRIEF LULL IN PRECIP IS EXPECTED BEHIND ANY EVENING CONVECTION BUT
NUMEROUS SHOWERS WILL REDEVELOP DURING THE NIGHT AS THE WRAPAROUND
PRECIP ARRIVES IN THE DEFORMATION ZONE. THIS WILL BE OF A MORE
SHOWERY AND LIGHTER NATURE...AND SHOULD NOT AGGRAVATE ANY WATER
PROBLEMS THAT MANAGE TO OCCUR. THIS PATTERN WILL CONTINUE THROUGH
SUNDAY MORNING...WITH PRECIP SLOWLY PULLING AWAY DURING THE
AFTERNOON AND EVENING. A LONGER DRY BREAK SUNDAY NIGHT WILL BE
FOLLOWED ANOTHER SYSTEM ON MONDAY...WITH MORE RAIN IN THE FORECAST.
TEMPERATURES WILL OF COURSE BE BELOW SEASONAL LEVELS IN THIS TROFFY
PATTERN. SUNDAY IN PARTICULAR LOOKS COOL WITH HIGHS REACHING THE
60S AT BEST. RECORD LOW MAXIMUM TEMPERATURES COULD BE CHALLENGED AT
PIT. CL
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
LONGER RANGE MODEL GUIDANCE FAVORS DRASTICALLY INCREASED RIDGING
IN THE WEST WITH DOWNSTREAM DEEPENING TROUGHING ACROSS THE GREAT
LAKES. THIS WILL LIKELY KEEP THINGS FAIRLY ACTIVE AND WET OVER THE
CWA...WITH TEMPERATURES LIKELY TO REMAIN A BIT BELOW NORMAL. MODEL
TIMING OF INDIVIDUAL SHORT WAVES IS EXCEEDINGLY SUSPECT AT THIS
JUNCTURE...HOWEVER MONDAY NIGHT INTO TUESDAY PROBABLY SEES THE
BEST SHOT AT WIDESPREAD RAIN SHOWERS ACROSS THE AREA. FRIES
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
WARM FRONT SHOULD SLOWLY LIFT ACROSS THE REGION THIS EVE AND
OVERNIGHT. AT THIS TIME...WITH CONVECTION FIRING IN CENTRAL
OHIO...DECIDED TO ADD A VCTS MENTION TO ZZV. FURTHER NORTH...WILL
LEAVE TS MENTION OUT AS THUNDERSTORM COVERAGE LOOKS TO BE LOWER
BASED ON MODEL SOUNDINGS AND THE TIMING OF PRECIP ONSET WITH THE
BOUNDARY. MAINLY MVFR CIG RESTRICTIONS ARE ANTICIPATED UNTIL THE
LOW APPROACHES OVERNIGHT AND STRATIFORM RAINFALL APPROACHES AT
WHICH POINT MOST SITES SHOULD EXPERIENCE A PERIOD OF IFR CIGS
AND/OR VISIBILITY.
CONDITIONS MAY IMPROVE TOWARD MORNING AS THE DRY SLOT APPROACHES.
STARTED AN UPWARD TREND BUT DID NOT GO BACK TO VFR AT THIS TIME.
THUNDERSTORMS MAY BE POSSIBLE TOMORROW AFTERNOON IF WE CAN SCATTER
OUT THE CLOUDS IN THE DRY SLOT.
.OUTLOOK.../FRIDAY NIGHT THROUGH TUESDAY/...
RESTRICTIONS ARE LIKELY OVER THE WEEKEND WITH PASSAGE OF A STRONG
LOW PRESSURE SYSTEM. AN APPROACHING COLD FRONT ON MONDAY MAY CAUSE
POSSIBLE RESTRICTIONS WITH RAIN.
&&
.HYDROLOGY...
A RAPIDLY DEEPENING SYSTEM WILL DROP HEAVY RAIN ONTO THE AREA
FRIDAY NIGHT INTO SATURDAY. AT THIS TIME...MOST OF THE AREA SEEMS
LIKELY TO RECEIVE 1 TO 1.75 INCHES THROUGH THE PERIOD...HOWEVER
SOME AREAS NORTH OF I-80 MAY SEE IN EXCESS OF 2 INCHES. LOCALIZED
URBAN AND SMALL STREAM FLOODING WILL BE THE MOST LIKELY
PROBLEM...HOWEVER AS THE TRACK OF THE SYSTEM IS PINNED DOWN MORE
CLOSELY...AND EXACT BASINS WHICH WILL RECEIVE THE MOST RAINFALL
ARE DETERMINED...A MORE ADEQUATE DETERMINATION OF THE RISK OF
RIVER FLOODING CAN BE MADE.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...FLOOD WATCH FROM 8 PM EDT THIS EVENING THROUGH SATURDAY
AFTERNOON FOR MDZ001.
OH...FLOOD WATCH FROM 8 PM EDT THIS EVENING THROUGH SATURDAY
AFTERNOON FOR OHZ039>041-048>050-057>059-068-069.
PA...FLOOD WATCH FROM 8 PM EDT THIS EVENING THROUGH SATURDAY
AFTERNOON FOR PAZ014-020>023-029-031-073>076.
FLOOD WATCH FROM 11 PM EDT THIS EVENING THROUGH LATE SATURDAY
NIGHT FOR PAZ007>009-013-015-016.
WV...FLOOD WATCH FROM 8 PM EDT THIS EVENING THROUGH SATURDAY
AFTERNOON FOR WVZ001>004-012-021>023-041.
&&
$$
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1231 PM CDT Fri Jun 26 2015
.SHORT TERM: (Tonight through Friday)
Issued at 322 AM CDT Fri Jun 26 2015
Active elements of large MCS over western MO will continue to move
south and southeast early this morning while the stratiform rain
area will continue to move east. RAP and HRRR continue to support
the solution that stratiform rain area with moderate to occasionally
heavy rain will slowly move east across the CWA today. RAP as well
as the GFS/NAM show strong 850-925 moisture convergence moving from
west to east across the area with PWATS near 2 inches. Will
maintain going flash flood watch given these parameters and the
saturated soils. Both the GFS and NAM show low level moisture
convergence shifting southeast of the CWA by 00Z with the upper
trough shifting east of the CWA by 06Z. Think that that the current
end time of the flash flood watch of 00Z still is okay because the
heavy rain should have ended by then. Rain chances overnight should
be just scattered showers over the southeast half of the CWA after
midnight.
Temperatures will be much cooler today behind the front with cloudy
skies, cold air advection, and rain. Highs in most areas will only
be in the 70s.
Britt
.LONG TERM: (Tonight through Thursday)
Issued at 322 AM CDT Fri Jun 26 2015
(Saturday and Sunday)
Dry weather is expect on Saturday as subsidence sets in behind the
exiting trough. Then chances of showers and thunderstorms increases
Sunday and Sunday night as a shortwave trough dives down embedded in
the northwestly flow aloft. MUCAPES will be in the 1500-2000 J/kg
range and deep layer shear will be in the 30-40kt range which may be
sufficient to produce a few isolated severe storms.
(Monday through Thursday)
Amplified upper pattern will dominate next week with shortwave
troughs moving through the area every other day. This will keep a
chance of showers and thunderstorm in the forecast during the period
with below normal temperatures.
Britt
&&
.AVIATION: (For the 18z TAFs through 18z Saturday Afternoon)
Issued at 1226 PM CDT Fri Jun 26 2015
Main concerns over the next 24 hours will be on chances of rain
and ceiling trends. Actual cold front is still across north-
central Missouri so will have to monitor chances for showers and
possibly a thunderstorm out ahead of this boundary. KUIN most
likely to see rain this afternoon whereas KCOU and metro St. Louis
TAF sites have a lesser chance so included a VCSH group for now.
Thinking ceiling trends will improve a bit through late this
afternoon before coming back down into MVFR...with IFR also
possible...particularly for metro St. Louis terminals. Ceilings
should scatter out by Saturday morning with northerly winds around
10 knots continuing.
Specifics for KSTL:
Main concerns over the next 24 hours will be on chances of rain
and ceiling trends. Actual cold front is still across north-
central Missouri so will have to monitor chances for showers and
possibly a thunderstorm out ahead of this boundary. Have a VCSH
group for late this afternoon/early this evening for nwo but will
continue to have to monitor. Thinking ceiling trends will improve
a bit through late this afternoon before coming back down into
MVFR...with IFR also possible late tonight. Ceilings should scatter out
by Saturday morning with northerly winds around 10 knots
continuing through Saturday afternoon.
Gosselin
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...FLASH FLOOD WATCH until 7 PM CDT this evening FOR Knox MO-Lewis
MO-Marion MO-Monroe MO-Pike MO-Ralls MO-Shelby MO.
IL...FLASH FLOOD WATCH until 7 PM CDT this evening FOR Adams IL-Brown
IL-Pike IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1229 PM CDT FRI JUN 26 2015
.UPDATE...
ISSUED AT 1151 AM CDT FRI JUN 26 2015
NO SIGNIF CHANGES...BUT DID ADJUST TEMPS TO SLOW THE FCST RISE
OVER S-CNTRL NEB WHERE CLOUDS WERE LIMITING HEATING. THE BAND OF
SHWRS DROPPING S HAS DISSIPATED. DID ADD SOME 20% POPS TO THE FCST
FOR ISOLATED SHWRS THAT MIGHT DEVELOP IN DAYTIME HEATING 4PM- 7PM.
CONFIDENCE IS LOW. FCST SOUNDINGS FROM THE RAP AND NAM INDICATE NO
CAP WHILE THE GFS MIXES DEEPER AND HAS A CAP. THE SOURCE REGION IS
FROM SD AND THE 12Z ABR SOUNDING DOES INDICATE INSTABILITY AND NO
CAP EVEN WITH MIXING OUT THE DWPT IN THE SFC LAYER.
THERE IS NO DISCERNIBLE FORCING MECHANISM...BUT BELIEVE ONE OR TWO
SHWRS COULD POP-UP. MOST LOCATIONS WILL REMAIN DRY AND ANYTHING
THAT DOES DEVELOP WILL DISSIPATE EARLY THIS EVE.
OVERALL...EXPECT A NICE AFTERNOON WITH A GOOD AMOUNT OF CU AND
STRATOCU.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 340 AM CDT FRI JUN 26 2015
A WEAKENING LINE OF SHOWERS AND ISOLATED THUNDERSTORMS IS MAKING
ITS WAY SOUTH ACROSS NORTHERN NEBRASKA THIS MORNING. SATELLITE AND
RADAR TRENDS SHOW THIS LINE IS WEAKENING RAPIDLY...AND ONLY KEPT
SOME SMALL POPS PRIMARILY NORTH OF HIGHWAY 92 DURING THE EARLY
MORNING HOURS TO REFLECT THIS. OTHERWISE...SKY COVER IS
ANTICIPATED TO DECREASE THROUGH THE MORNING HOURS...WITH A PARTLY
TO MOSTLY SUNNY AFTERNOON ALONG WITH PLEASANT TEMPERATURES IN
STORE.
OVERNIGHT...EXPECT SURFACE HIGH PRESSURE TO TRANSITION FROM THE
HIGH PLAINS TOWARDS THE MISSOURI RIVER VALLEY...RESULTING IN LIGHT
WINDS ACROSS THE LOCAL AREA. WITH LIGHT WINDS...AND MAINLY CLOUD
FREE SKIES...FELT SAFE UNDERCUTTING GUIDANCE A FEW DEGREES ON LOW
TEMPERATURES TO START THE WEEKEND...WITH LOWS EXPECTED TO DIP INTO
THE MID TO UPPER 50S ACROSS THE MAJORITY OF THE FORECAST AREA.
OTHER THAN THE SMALL CHANCE FOR SHOWERS WITH A WEAK UPPER WAVE
VISIBLE IN WV IMAGERY TO OUR NORTH THIS MORNING...EXPECT DRY
CONDITIONS OVER THE NEXT 24 HOURS WITH LIGHT WINDS AND SEASONABLY
COOL TEMPERATURES FOR LATE JUNE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 340 AM CDT FRI JUN 26 2015
LOOKING AT THE START OF THE LONG TERM PERIOD SATURDAY
MORNING...MODELS ARE IN GOOD AGREEMENT SHOWING A WELL AMPLIFIED
UPPER LEVEL PATTERN ACROSS THE CONUS. HIGH PRESSURE CENTERED OVER
THE NV/UT/AZ BORDER AREA IS RESULTING IN RIDGING WELL NORTH INTO WRN
CANADA...WHILE AN AREA OF LOW PRESSURE IS EXPECTED TO BE LOCATED
OVER THE MIDWEST REGION. THE RESULT OVER THE CENTRAL PLAINS IS SHARP
N/NWRLY FLOW...AND AT THIS TIME NO NOTABLE DISTURBANCES IN THE
IMMEDIATE AREA. LITTLE CHANGE IN THE FLOW IS EXPECTED FOR THIS
UPCOMING WEEKEND...AND WHILE NO DISTURBANCES LOOK TO PASS DIRECTLY
OVER THE CWA...MODELS ARE IN GOOD AGREEMENT SHOWING ONE PASSING
SOUTH THROUGH THE MAIN FLOW JUST OFF TO OUR EAST. THE CURRENT
FORECAST REMAINS A DRY ONE...BUT A LITTLE UNCERTAINTY EXISTS WITH
THAT...MAINLY DURING THE LATE SUNDAY AFTERNOON/EVENING HOURS. WHILE
THE SURFACE PATTERN ACROSS THE AREA ON SATURDAY IS DOMINATED BY HIGH
PRESSURE...BRINGING FAIRLY LIGHT WINDS...SUNDAY A FRONTAL BOUNDARY
WILL BE PUSHED SOUTH THROUGH THE AREA BY THIS UPPER LEVEL
DISTURBANCE. SIMILAR TO RECENT FRONTAL PASSAGES...NOT LOOKING AT A
NOTABLE DROP IN TEMPS...BUT IT WILL USHER IN ANOTHER ROUND OF NRLY
WINDS ACROSS THE CWA DURING THE DAYTIME HOURS. SOME MODELS SUGGEST
THE DEVELOPMENT OF THUNDERSTORMS IN PROXIMITY TO THIS FRONT...WHICH
BY LATE SUNDAY AFTERNOON SHOULD BE JUST SOUTH OF THE CWA...BUT IS
CLOSE ENOUGH TO ESP OUR NC KS COUNTIES THAT IT WOULDNT TAKE MUCH OF
A SLOW DOWN FROM MODELS AND POPS MAY NEED TO BE ADDED TO THE
FORECAST. WILL SEE HOW THINGS TREND. FORECAST STILL CALLING FOR
DEWPOINTS THIS WEEKEND TO BE IN THE MID 50S TO LOWER 60S...WITH
HIGHS IN THE 80S FOR MOST OF THE CWA...THOUGH A FEW LOWER 90S ARE
POSSIBLE MAINLY ACROSS NC KS.
AS WE GET INTO THE NEXT WORK WEEK...MONDAY THROUGH
THURSDAY...THUNDERSTORM CHANCES DO EVENTUALLY MAKE THEIR WAY BACK
INTO THE FORECAST. MONDAY MORNING...OVERALL NOT A LOT OF CHANGE IS
EXPECTED LOOKING AT THE UPPER LEVEL PATTERN...REMAINING WELL
AMPLIFIED. HOWEVER...A COUPLE OF PIECES OF SHORTWAVE ENERGY ARE
SHOWN BY MODELS TO BE WORKING INTO THE PAC NW REGION MONDAY
MORNING...BREAKING DOWN THE RIDGE A TOUCH AS WE GET INTO TUESDAY.
THE NEXT CHANCED FOR THUNDERSTORMS CURRENTLY IN THE FORECAST COME
TUESDAY NIGHT THROUGH THURSDAY...AS THESE WEAKER DISTURBANCES MOVE
THROUGH THE MORE NWRLY FLOW. CONFIDENCE THOUGH IS ON THE LOWER
SIDE...WITH SOME DIFFERENCES IN MODELS STILL IN PLACE TO BE WORKED
OUT IN THE COMING DAYS. OTHERWISE...NO BIG SWINGS IN TEMPERATURES
EXPECTED...WITH HIGHS GENERALLY IN THE 80S.
&&
.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z SAT AFTERNOON)
ISSUED AT 1229 PM CDT FRI JUN 26 2015
THIS AFTERNOON: VFR WITH SCT 2000-2500 FT STRATOCU LIFTING TO
AROUND 5K FT. THERE IS A LOW PROBABILITY OF A BRIEF SHWR PRIMARILY
AFTER 20Z. N WINDS 10-12 KTS WITH OCCASIONAL G17-18 KTS.
CONFIDENCE: MEDIUM
TONIGHT: BECOMING VFR SKC BY 02Z. LGT AND VRBL OR CALM WINDS.
CONFIDENCE: HIGH
SAT THRU 18Z: VFR WITH A FEW STRATOCU DEVELOPING AFTER 15Z. LIGHT
NW WINDS. CONFIDENCE: HIGH
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...ROSSI
LONG TERM...ADP
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1227 PM CDT FRI JUN 26 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 333 AM CDT FRI JUN 26 2015
THE CHANCE FOR THUNDERSTORMS TODAY IS THE PRIMARY FORECAST CONCERN.
THEN A GENERALLY DRY AND WARMER WEEKEND...WITH THE EXCEPTION OF A
SMALL CHANCE FOR STORMS SUNDAY.
NORTHWEST MID LEVEL FLOW ACROSS THE PLAINS WAS NOTED ON EVENING
UPPER AIR CHARTS AND SHORT TERM MODEL OUTPUT. A COUPLE OF SHORTWAVES
COULD BE IDENTIFIED WITHIN THE FLOW...AND RECENT RAP HEIGHT
FORECASTS ALONG WITH WATER VAPOR IMAGERY SUGGESTED ONE WAVE WAS
MOVING OUT OF SOUTHEAST NEBRASKA AS OF 3 AM...AND ANOTHER WAS
APPROACHING NORTHEAST NEBRASKA FROM SOUTH DAKOTA. BOTH WAVES WERE
TRIGGERING SCATTERED SHOWERS AND STORMS...HOWEVER THE STRONGEST WERE
IN NORTHERN KANSAS WHERE LIFT WAS MAXIMIZED JUST NORTH OF FRONTAL
BOUNDARY EXTENDING FROM KANSAS CITY TO WICHITA.
GIVEN NORTHWEST FLOW ALOFT...SOUTHERN STORMS MOVING OUT OF OUR AREA
WILL REMAIN THERE THIS MORNING. SHORTWAVE TO THE NORTH WILL
GRADUALLY WORK SOUTHEAST TODAY...BUT ABSENCE OF SURFACE BOUNDARY/LOW
LEVEL CONVERGENCE SUGGESTS ACTIVITY WILL REMAIN ISOLATED TO
SCATTERED IN NATURE. IN FACT...MANY SHORT RANGE MESOSCALE MODELS
INCLUDING HRRR AND RAP SUGGEST A DECREASE IN ACTIVITY THROUGH THE
MORNING BEFORE AFTERNOON HEATING HELPS BUBBLE UP WIDELY SCATTERED
AFTERNOON CONVECTION. SO WILL PLAY THE HIGHEST POPS IN NORTHEAST
NEBRASKA THIS MORNING...THEN BROADBRUSH SMALL CHANCES THROUGH THE
AFTERNOON ACROSS MUCH OF EASTERN NEBRASKA AND SOUTHWEST IOWA. COULD
SEE SOME LINGERING SHOWERS/STORMS IN SOUTHEAST NEBRASKA OR SOUTHWEST
IOWA DURING THE EARLY EVENING BEFORE SHORTWAVE PUSHES FARTHER AWAY
AND WE LOSE AFTERNOON HEATING.
OTHERWISE WE WILL SEE A TENDENCY TOWARD NORTHERLY LOW LEVEL FLOW
TONIGHT AND SATURDAY AS HIGH PRESSURE SETTLES ACROSS THE
REGION...AND BRINGS SLIGHTLY DRIER AIR INTO OUR AREA. SHOULD SEE
PLENTY OF SUNSHINE SATURDAY WITH HIGHS IN THE LOWER 80S AFTER
MORNING LOWS IN THE LOWER 60S.
SOUTHERLY FLOW WILL RETURN SATURDAY NIGHT AS A SHORTWAVE DIVES INTO
MINNESOTA THEN EVENTUALLY IOWA/WISCONSIN/ILLINOIS. SURFACE COLD
FRONT WILL FOLLOW THIS WAVE AND SWEEP THROUGH EASTERN NEBRASKA AND
SOUTHWEST IOWA ON SUNDAY. CONVECTION SATURDAY NIGHT SHOULD BE
CONFINED TO AREAS TO OUR NORTHEAST WHERE STRONG WARM ADVECTION IS
REALIZED JUST AHEAD OF MID LEVEL WAVE. ON SUNDAY...AXIS OF BEST LIFT
NEAR SHORTWAVE AND SURFACE REFLECTION WILL STILL LIE WELL TO OUR
EAST AND NORTHEAST IN MINNESOTA AND IOWA...BUT COULD SEE A FEW
SHOWERS OR STORMS NEAR AND EAST OF THE NEBRASKA/IOWA BORDER AS COLD
FRONT SWINGS SOUTHEAST. SHOULD SEE NICE WARMING ON SUNDAY AS
SOUTHWEST FLOW AHEAD AND NORTHWEST FLOW BEHIND FRONT WILL PROMOTE
DECENT MIXING. HIGHS THEN SHOULD EASILY REACH THE MID AND UPPER
80S.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 333 AM CDT FRI JUN 26 2015
GENERAL MID LEVEL FLOW PATTERN CHANGES ONLY A LITTLE DURING THE
WEEK. BROAD HIGH PRESSURE WILL REMAIN OVER THE SOUTHWESTERN STATES
THROUGH THE PERIOD. MEANWHILE UPPER LOW IN THE EASTERN GREAT LAKES
EARLY IN THE PERIOD WILL LIFT TO THE NORTHEAST...LEAVING BROAD
TROUGH BEHIND OVER THE EASTERN HALF OF THE COUNTRY. IN BETWEEN THESE
FEATURES...FLOW IN THE CENTRAL PLAINS WILL SHIFT FROM NEARLY
NORTHERLY TO NORTHWESTERLY BY MID WEEK. SEVERAL IMPULSES RIDING OVER
WESTERN RIDGE WILL ENTER THE PLAINS...BRINGING OFF AND ON
THUNDERSTORM CHANCES TO OUR REGION. GFS AND ECMWF ARE IN FAIRLY GOOD
AGREEMENT WITH THIS OVERALL PATTERN CHANGE...BUT DIFFER ON TIMING OF
PRECIPITATION-PRODUCING SHORTWAVES.
HOWEVER BOTH MODELS ARE RELATIVELY SIMILAR IN DROPPING A MORE
SIGNIFICANT SHORTWAVE INTO THE PLAINS ON TUESDAY...INCREASING
THUNDERSTORM CHANCES IN EASTERN NEBRASKA AND WESTERN IOWA TUESDAY
NIGHT AS ATTENDANT SURFACE LOW AND FRONTAL SYSTEM MOVE THROUGH THE
REGION. WILL HAVE THE HIGHEST PRECIP CHANCES AT THIS TIME...THOUGH
STILL ONLY IN THE CHANCE CATEGORY AS MOISTURE RETURN AFTER SUNDAY
COLD FRONT WILL BE SLOW TO OCCUR. SHOULD SEE MINIMAL RAIN CHANCES
BEHIND THIS SYSTEM ON WEDNESDAY AND THURSDAY...BUT GIVEN UNCERTAINTY
IN SMALL-SCALE MID LEVEL FEATURES...CAN NOT RULE OUT A STRAY STORM
OR TWO. OTHERWISE EXPECT TEMPERATURES TO AVERAGE 60S AND 80S FOR
LOWS AND HIGHS THROUGH THE PERIOD.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1226 PM CDT FRI JUN 26 2015
VFR CONDITIONS ARE EXPECTED TO PREVAIL AT ALL TAF SITES. A FEW
SHOWERS AND THUNDERSTORMS COULD POP UP THIS AFTERNOON WITH DAYTIME
HEATING...HOWEVER CONFIDENCE IN COVERAGE STILL REMAINS FAIRLY LOW.
NORTHERLY WINDS WILL BECOME LIGHT AND VARIABLE TONIGHT WITH SKIES
CLEARING THROUGH SATURDAY MORNING.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...DERGAN
LONG TERM...DERGAN
AVIATION...KG
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1225 PM CDT FRI JUN 26 2015
.SYNOPSIS...
ISSUED AT 336 AM CDT FRI JUN 26 2015
AT 08Z...ISOLATED SHOWERS CONTINUE TO TRAIL TO THE WEST ACROSS
NCTRL NEBR BUT HAVE SHOWN RECENT TRENDS OF SLOWLY DISSIPATING AS
THEY DROP SOUTHWARD. MOST OF THE THUNDERSTORM ACTIVITY RESIDES
ACROSS PARTS OF KS AND MO. UPSTREAM ACROSS THE WRN DAKOTAS...MT
AND WYOMING SKIES ARE CLEAR IN MOST AREAS. TEMPERATURES IN WRN
NEBR RANGE FROM 59 TO 64 DEGREES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 336 AM CDT FRI JUN 26 2015
TODAY...THE H5 UPPER TROUGH AXIS AND ASSOCIATED VORT MAX AT 12Z
TO BE LOCATED IN WRN IA. UPSTREAM...THERE WILL BE CHANNELIZED
VORTICITY TODAY. WHILE THIS WOULD SEEM SUPPORTIVE OF AT LEAST
ISOLATED SHOWERS ACROSS THE ERN HALF OF FA AS INDICATED BY THE
HRRR AND RAP MODELS...LATEST NAM AND GFS ARE DRIER. A CROSS
SECTION ACROSS EASTERN AREAS SHOWS SUFFICIENT MOISTURE AVBL
EXCEPT THAT GENERAL SUBSIDENCE NOTED. CURRENT FCST IS DRY
TODAY...ALTHOUGH ISOLATED SHOWERS WOULD BE POSSIBLE. CURRENT BAND
OF SHOWERS EAST-WEST ACROSS CHERRY COUNTY TO HOLT COUNTY
CONTINUES TO DIMINISH IN COVERAGE AND EXPECTED TO DISSIPATED BY
12Z. THERE IS HOWEVER INCREASING COVERAGE OF STRATUS ACROSS THE
CENTRAL SANDHILLS INCLUDING THEDFORD ATTM. SATELLITE TRENDS SHOWS
AREA IS DEVELOPING TO THE SOUTHWEST WITH MAINLY MID LEVEL CLOUDS
COVERING NCTRL NEBR. ANY STRATUS SHOULD BEGIN TO SCATTER OUT
AFTER 15Z WITH SCT TO BKN STRATOCUMULUS EXPECTED TODAY. HIGHS
TODAY NEAR PREVIOUS FCST FROM 77 TO 81 DEGREES. WINDS STEADY
NORTH TO NORTHEAST 5 TO 10 MPH.
LOOKING SYNOPTICALLY ACROSS THE CONUS...THE UPPER RIDGE WILL
INTENSIFY ACROSS THE WRN CONUS AS THE UPPER TROUGH AMPLIFIES FROM
THE GREAT LAKES INTO THE MID MISSISSIPPI VALLEY. WEAK SURFACE
HIGH PRESSURE WILL BUILD SOUTH FROM THE NRN INTO THE CNTRL
PLAINS.
TONIGHT...UPPER FLOW WILL REMAIN NWRLY AS SURFACE HIGH PRESSURE
RESIDES OVER THE CENTRAL PLAINS. SKIES EXPECTED TO BE MOSTLY
CLEAR AND TEMPERATURES WILL BE COOLER FROM 55 TO 59 DEGREES.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 336 AM CDT FRI JUN 26 2015
THIS WEEKEND INTO THE FIRST OF NEXT WEEK WILL SEE A RIDGE
DOMINATE THE WESTERN CONUS AS A TROUGH DIGS OVER THE GREAT LAKES
REGION. NORTHWEST FLOW ACROSS THE HIGH PLAINS...HOWEVER THE RIDGE
RIDING SHORT WAVES/STORMS ARE EXPECTED TO REMAIN TO THE NORTHEAST
OF THE CWA. TEMPS ABOVE NORMAL /MORE SUMMER LIKE/ WITH HIGHS IN
THE MID 80S TO LOWER 90S.
MONDAY NIGHT INTO TUESDAY A STRONG DISTURBANCE WILL RIDE THE
CREST OF THE RIDGE AND CAUSE A SFC LOW PRESSURE TO DEVELOP ON THE
LEE SIDE OF THE ROCKIES. BY TUESDAY NIGHT THE LOW PRESSURE ALONG
WITH A TRAILING WEAK COLD FRONT WILL SLIDE SOUTH ACROSS THE
CENTRAL/HIGH PLAINS. MODELS STILL DIFFERING ON THE STRENGTH OF
LOW PRESSURE AND HOW STRONG THE CAP WILL BE. THUS STORMS ARE
POSSIBLE BUT THERE IS GREAT UNCERTAINTY. THE LATEST GFS HAS GONE
DRIER WHILE THE ECMWF HAS INCREASED QPF ACROSS THE AREA. ONE
AGREEMENT IS A SLIGHT BOOST OF TEMPS FOR TUESDAY AHEAD OF THE
FRONT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1223 PM CDT FRI JUN 26 2015
LOW CIGS FROM MORNING STRATUS DECK WILL CONTINUE TO RISE THIS
AFTERNOON. CLOUD COVER WILL BEGIN TO DECREASE THIS EVENING WITH
SKC EXPECTED OVERNIGHT AND INTO SATURDAY MORNING. VFR CONDITIONS
WILL PREVAIL ACROSS ALL OF WESTERN AND NORTH CENTRAL NEBRASKA
THROUGH THE CURRENT TAF PERIOD.
&&
.HYDROLOGY...
ISSUED AT 336 AM CDT FRI JUN 26 2015
CURRENT FLOOD WARNINGS FOR BRADY ON THE PLATTE RIVER SYSTEM AND
LEWELLEN ON THE NORTH PLATTE RIVER SYSTEM REMAIN IN PLACE. RIVER
LEVELS CONTINUE TO SLOWLY FALL. THE SOUTH PLATTE RIVER AT ROSCOE
IS CURRENTLY JUST BELOW FLOOD STAGE AT 8.9 FEET AND WILL CONTINUE
TO SLOWLY FALL THROUGH EARLY NEXT WEEK WITH THE FLOOD ADVISORY TO
CONTINUE. THE SOUTH PLATTE RIVER AT NORTH PLATTE IS CURRENTLY
NEAR 12.35 FEET AND WILL ALSO SLOWLY FALL THROUGH EARLY NEXT WEEK
WITH THE FLOOD ADVISORY TO CONTINUE. RECENT RAINFALL FROM LAST
EVENING DOES NOT APPEAR TO CAUSE CONCERN FOR ANY RISES...ONLY A
SLIGHTLY LESS FALL IN STAGE IN THE NEAR TERM. RIVER LEVELS ALONG
THE NORTH PLATTE RIVER UPSTREAM OF LAKE MCCONAUGHY ARE ELEVATED
NEAR ACTION STAGE AT LISCO WHILE REMAINING ABOVE MINOR FLOOD
STAGE AT LEWELLEN THROUGH EARLY NEXT WEEK.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...ROBERG
SHORT TERM...ROBERG
LONG TERM...MASEK
AVIATION...MARTIN
HYDROLOGY...ROBERG
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1151 AM CDT FRI JUN 26 2015
.UPDATE...
ISSUED AT 1151 AM CDT FRI JUN 26 2015
NO SIGNIF UPDATES CHANGES...BUT DID ADJUST TEMPS TO SLOW THE FCST
RISE OVER S-CNTRL NEB WHERE CLOUDS WERE LIMITING HEATING. THE
BAND OF SHWRS DROPPING S HAS DISSIPATED. DID ADD SOME 20% POPS TO
THE FCST FOR ISOLATED SHWRS THAT MIGHT DEVELOP IN DAYTIME HEATING
4PM- 7PM. CONFIDENCE IS LOW. FCST SOUNDINGS FROM THE RAP AND NAM
INDICATE NO CAP WHILE THE GFS MIXES DEEPER AND HAS A CAP. THE
SOURCE REGION IS FROM SD AND THE 12Z ABR SOUNDING DOES INDICATE
INSTABILITY AND NO CAP EVEN WITH MIXING OUT THE DWPT IN THE SFC
LAYER.
THERE IS NO DISCERNIBLE FORCING MECHANISM...BUT BELIEVE ONE OR TWO
SHWRS COULD POP-UP. MOST LOCATIONS WILL REMAIN DRY AND ANYTHING
THAT DOES DEVELOP WILL DISSIPATE EARLY THIS EVE.
OVERALL...EXPECT A NICE AFTERNOON WITH A GOOD AMOUNT OF CU AND
STRATOCU.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 340 AM CDT FRI JUN 26 2015
A WEAKENING LINE OF SHOWERS AND ISOLATED THUNDERSTORMS IS MAKING
ITS WAY SOUTH ACROSS NORTHERN NEBRASKA THIS MORNING. SATELLITE AND
RADAR TRENDS SHOW THIS LINE IS WEAKENING RAPIDLY...AND ONLY KEPT
SOME SMALL POPS PRIMARILY NORTH OF HIGHWAY 92 DURING THE EARLY
MORNING HOURS TO REFLECT THIS. OTHERWISE...SKY COVER IS
ANTICIPATED TO DECREASE THROUGH THE MORNING HOURS...WITH A PARTLY
TO MOSTLY SUNNY AFTERNOON ALONG WITH PLEASANT TEMPERATURES IN
STORE.
OVERNIGHT...EXPECT SURFACE HIGH PRESSURE TO TRANSITION FROM THE
HIGH PLAINS TOWARDS THE MISSOURI RIVER VALLEY...RESULTING IN LIGHT
WINDS ACROSS THE LOCAL AREA. WITH LIGHT WINDS...AND MAINLY CLOUD
FREE SKIES...FELT SAFE UNDERCUTTING GUIDANCE A FEW DEGREES ON LOW
TEMPERATURES TO START THE WEEKEND...WITH LOWS EXPECTED TO DIP INTO
THE MID TO UPPER 50S ACROSS THE MAJORITY OF THE FORECAST AREA.
OTHER THAN THE SMALL CHANCE FOR SHOWERS WITH A WEAK UPPER WAVE
VISIBLE IN WV IMAGERY TO OUR NORTH THIS MORNING...EXPECT DRY
CONDITIONS OVER THE NEXT 24 HOURS WITH LIGHT WINDS AND SEASONABLY
COOL TEMPERATURES FOR LATE JUNE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 340 AM CDT FRI JUN 26 2015
LOOKING AT THE START OF THE LONG TERM PERIOD SATURDAY
MORNING...MODELS ARE IN GOOD AGREEMENT SHOWING A WELL AMPLIFIED
UPPER LEVEL PATTERN ACROSS THE CONUS. HIGH PRESSURE CENTERED OVER
THE NV/UT/AZ BORDER AREA IS RESULTING IN RIDGING WELL NORTH INTO WRN
CANADA...WHILE AN AREA OF LOW PRESSURE IS EXPECTED TO BE LOCATED
OVER THE MIDWEST REGION. THE RESULT OVER THE CENTRAL PLAINS IS SHARP
N/NWRLY FLOW...AND AT THIS TIME NO NOTABLE DISTURBANCES IN THE
IMMEDIATE AREA. LITTLE CHANGE IN THE FLOW IS EXPECTED FOR THIS
UPCOMING WEEKEND...AND WHILE NO DISTURBANCES LOOK TO PASS DIRECTLY
OVER THE CWA...MODELS ARE IN GOOD AGREEMENT SHOWING ONE PASSING
SOUTH THROUGH THE MAIN FLOW JUST OFF TO OUR EAST. THE CURRENT
FORECAST REMAINS A DRY ONE...BUT A LITTLE UNCERTAINTY EXISTS WITH
THAT...MAINLY DURING THE LATE SUNDAY AFTERNOON/EVENING HOURS. WHILE
THE SURFACE PATTERN ACROSS THE AREA ON SATURDAY IS DOMINATED BY HIGH
PRESSURE...BRINGING FAIRLY LIGHT WINDS...SUNDAY A FRONTAL BOUNDARY
WILL BE PUSHED SOUTH THROUGH THE AREA BY THIS UPPER LEVEL
DISTURBANCE. SIMILAR TO RECENT FRONTAL PASSAGES...NOT LOOKING AT A
NOTABLE DROP IN TEMPS...BUT IT WILL USHER IN ANOTHER ROUND OF NRLY
WINDS ACROSS THE CWA DURING THE DAYTIME HOURS. SOME MODELS SUGGEST
THE DEVELOPMENT OF THUNDERSTORMS IN PROXIMITY TO THIS FRONT...WHICH
BY LATE SUNDAY AFTERNOON SHOULD BE JUST SOUTH OF THE CWA...BUT IS
CLOSE ENOUGH TO ESP OUR NC KS COUNTIES THAT IT WOULDNT TAKE MUCH OF
A SLOW DOWN FROM MODELS AND POPS MAY NEED TO BE ADDED TO THE
FORECAST. WILL SEE HOW THINGS TREND. FORECAST STILL CALLING FOR
DEWPOINTS THIS WEEKEND TO BE IN THE MID 50S TO LOWER 60S...WITH
HIGHS IN THE 80S FOR MOST OF THE CWA...THOUGH A FEW LOWER 90S ARE
POSSIBLE MAINLY ACROSS NC KS.
AS WE GET INTO THE NEXT WORK WEEK...MONDAY THROUGH
THURSDAY...THUNDERSTORM CHANCES DO EVENTUALLY MAKE THEIR WAY BACK
INTO THE FORECAST. MONDAY MORNING...OVERALL NOT A LOT OF CHANGE IS
EXPECTED LOOKING AT THE UPPER LEVEL PATTERN...REMAINING WELL
AMPLIFIED. HOWEVER...A COUPLE OF PIECES OF SHORTWAVE ENERGY ARE
SHOWN BY MODELS TO BE WORKING INTO THE PAC NW REGION MONDAY
MORNING...BREAKING DOWN THE RIDGE A TOUCH AS WE GET INTO TUESDAY.
THE NEXT CHANCED FOR THUNDERSTORMS CURRENTLY IN THE FORECAST COME
TUESDAY NIGHT THROUGH THURSDAY...AS THESE WEAKER DISTURBANCES MOVE
THROUGH THE MORE NWRLY FLOW. CONFIDENCE THOUGH IS ON THE LOWER
SIDE...WITH SOME DIFFERENCES IN MODELS STILL IN PLACE TO BE WORKED
OUT IN THE COMING DAYS. OTHERWISE...NO BIG SWINGS IN TEMPERATURES
EXPECTED...WITH HIGHS GENERALLY IN THE 80S.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z SAT MORNING)
ISSUED AT 653 AM CDT FRI JUN 26 2015
WHILE A VCSH IS NOT OUT OF THE QUESTION OVER THE NEXT FEW
HOURS...VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD AS HIGH
PRESSURE BEGINS TO APPROACH THE AREA FROM THE WEST. EXPECT MID
LEVEL CLOUD COVER THIS MORNING TO BEGIN TO BREAK UP OVER THE NEXT
SEVERAL HOURS...WITH CLEAR SKIES AND LIGHT NORTHERLY WINDS
EXPECTED THEREAFTER.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...ROSSI
LONG TERM...ADP
AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS ELKO NV
149 PM PDT FRI JUN 26 2015
.SYNOPSIS...HIGH PRESSURE REMAINS ENTRENCHED OVER
THE BATTLE BORN STATE RESULTING IN TRIPLE DIGIT
TEMPERATURES AND ISOLATED AFTERNOON THUNDERSTORMS.
EXPECT THE HEAT WAVE TO PERSIST THROUGH MONDAY.
&&
.SHORT TERM...TODAY THROUGH SUNDAY. 595 500MB HIGH IS CENTERED
ALONG THE UT/NV BORDER WITH AN WEAK 500MB LOW WELL OFF THE
SOUTHERN CA COAST. THIS SETUP IS DRAWING SOME MOISTURE INTO THE
CWA AND CREATING UNSTABLE CONDITIONS ALOFT. SOME ISOLATED
THUNDERSTORMS ARE DEVELOPING OVER NORTHERN NYE AND SOUTHERN
LANDER/EUREKA COUNTIES WHERE THE DEEPER MOISTURE EXIST.
NAM12...RAP...AND HRRR MODELED RADAR OUTPUT AGREE WITH THIS
ASSESSMENT...BUT ALSO POINT SOME ISOLATED CONVECTION IN HUMBOLDT
COUNTY. ALTHOUGH PW VALUES INCREASED THE PAST 24HRS...ANY
THUNDERSTORMS THAT DO DEVELOP WILL STILL REMAIN ON THE DRY;
THEREFORE THE MAIN THREAT FROM THESE IS GUSTY OUTFLOW WINDS. THIS
SOUTHERN FLOW ALOFT WILL BUILD THE RIDGE FURTHER OVER THE AREA
TOMORROW...PUSHING 500MB HEIGHTS TO 598DM. ONCE AGAIN PW HANGS
AROUND .5 TO .6 AS MOISTURE REMAINS TRAPPED UNDERNEATH THE
RIDGE...SO ISOLATED DRY THUNDERSTORMS ARE POSSIBLE OVER THE HIGHER
MTNS TOPS. RIDGE AXIS ORIENTATION BECOMES MORE NORTH TO SOUTH AND
SHIFTS EAST SLIGHTLY ON SUNDAY AS THE ABOVE MENTIONED UPPER LEVEL
LOW LIFTS NORTH TO OREGON...ALLOWING ADDITIONAL MOISTURE TO BE
PULLED INTO THE AREA... AND INCREASING THE CHANCES OF
THUNDERSTORMS WITH SOME TRANSITIONING TO WET OVER THE HIGHER
TERRAIN. THE HIGHEST MOISTURE VALUES ARE POSITIONED ALONG THE
WESTERN EDGE...PUSHING 1 INCH IN WESTERN HUMBOLDT COUNTY. AS FOR
THE HEAT ADV...IT STILL LOOKS VALID; THEREFORE NO CHANGES MADE AT
THIS TIME.
.LONG TERM...SUNDAY NIGHT THROUGH NEXT FRIDAY. HIGH PRESSURE WILL
REMAIN STRONG AND CENTERED WEST OF THE 4 CORNERS AREA OF THE COUNTRY
THROUGH THURSDAY BEFORE MODELS INDICATE A BREAKDOWN OF THE RIDGE
PATTERN. PERSISTENCE WILL BE THE KEY TO TEMPERATURES ALL THROUGH THE
PERIOD AND MOISTURE WILL CREEP NORTH THROUGH THE LKN CWFA. 100
DEGREE TEMPERATURES WILL CONTINUE...FAVORING WESTERN NEVADA. HOWEVER
DUE TO THE ECCENTRIC NATURE OF THE SYNOPTIC RIDGE...INSTABILITY
ASSOCIATED WITH THE MOISTURE INFLUX UNDERNEATH THE RIDGE MAY BE
INTERMITTENT WITH A PULSE ATTRIBUTE DUE TO THE OSCILLATIONS OF THE
RIDGE AXIS. DO NOT THINK THERE WILL BE OVERNIGHT CONVECTION AT THIS
POINT HOWEVER THUNDERSTORMS WITH LITTLE OR NO RAINFALL IS EXPECTED
EACH AFTERNOON AND EVENING WITH ISOLATED ACTIVITY POSSIBLE ALL
ACROSS THE LKN CWFA.
&&
.AVIATION...VFR CONDITIONS ARE EXPECTED AT KWMC KEKO KELY AND KTPH
THROUGH SATURDAY AFTERNOON.
NOTE: LIGHTNING SENSOR AT KWMC HAS BEEN TEMPORARILY TURNED OFF TO
ELIMINATE FALSE REPORTS OF VCTS. REPAIRS WILL EFFECTED WHEN
POSSIBLE.
&&
.FIRE WEATHER...MAINLY HOT AND DRY...HAINES OF 6 IMMINENT. WITH THE
RIDGE IN PLACE EXPECTING A MAJOR HEAT WAVE. SOME MOISTURE WILL BE
ABLE TO WORK ITS WAY AROUND THE BACK SIDE OF THE RIDGE SUPPORTING
ISOLATED DRY THUNDERSTORMS TODAY AND TOMORROW...WITH A TRANSITION
TO ISOLATED WET THUNDERSTORMS IN THE HIGHER TERRAIN ON SUNDAY. ANY
OF THESE THUNDERSTORMS MAY PRODUCE ERRACTIC AND GUSTY SURFACE
WINDS.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 8 PM PDT SUNDAY FOR HUMBOLDT COUNTY-NORTHERN
LANDER COUNTY AND NORTHERN EUREKA COUNTY.
&&
$$
85/92/92
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
313 PM MDT FRI JUN 26 2015
.SYNOPSIS...
THOUGH STORMS HAVE BEEN SLOW TO START THIS AFTERNOON...THEY ARE
EXPECTED TO INCREASE IN COVERAGE THIS EVENING. STORM MOTIONS WILL
BE SLOW AND HEAVY RAIN IS POSSIBLE. THANKS TO THE BACK DOOR FRONT
AND ASSOCIATED MOISTURE SURGE FROM TODAY...AN ACTIVE PATTERN IS
EXPECTED FOR THE WEEKEND INTO MONDAY WITH WIDESPREAD STORMS
PRODUCING HEAVY RAINFALL. AREAS OF FLASH FLOODING WILL BE
POSSIBLE. STORM COVERAGE WILL TREND DOWNWARD ON TUESDAY...BUT
WILL RAMP BACK UP LATER IN THE WEEK.
&&
.DISCUSSION...
BACK DOOR COLD FRONT NUDGED UP TO THE CENTRAL MOUNTAIN CHAIN THIS
MORNING...AND HAS BEEN STUCK THERE SINCE. LATEST HRRR SUGGESTS IT
MAY BE A FEW HOURS YET UNTIL THE FRONT IS ABLE TO PUSH THROUGH THE
GAPS OF THE CENTRAL MOUNTAIN CHAIN...BUT SHOULD OCCUR BY 02-03Z.
WHEN THAT DOES OCCUR...COULD SEE SOME STORMS DEVELOP IN THE ABQ
METRO AREA.
MEANWHILE...DUE TO THE FRONTS EARLY ARRIVAL...IT HAS TAKEN A BIT
FOR STORMS TO DEVELOP SINCE AREAS ALONG THE EAST SLOPES HAVE NOT
YET REACHED THERE CONVECTIVE TEMPERATURE. THIS WILL OCCUR LATER
THIS AFTERNOON...AND STORMS ARE EXPECTED TO ROLL SOUTH OFF THE
HIGHER TERRAIN INTO THE CENTRAL HIGH PLAINS. THE HRRR SHOWS STORMS
FURTHER EAST...BUT THE NAM MAKES MORE SENSE AT THIS POINT THAT
UPSLOPE FLOW AND OROGRAPHICS WILL BE THE MAIN TRIGGER FOR STORMS
AND STORM MOTION WILL TAKE THEM SLOWLY SOUTH...IF NOT SW. MOISTURE
VALUES LOOK TO BE AROUND 125 PERCENT OF NORMAL...THUS STORMS WILL
BE CAPABLE OF PRODUCING HEAVY RAIN. THEREFORE...THE FLASH FLOOD
WATCH WILL REMAIN INTACT...BUT CERTAINLY BEARS WATCHING.
STORMS SHOULD INITIATE A BIT EARLIER ON SATURDAY...AND FAVOR THE
HIGH TERRAIN INITIALLY. STORM MOTIONS WILL BE SLOW ONCE AGAIN...
ESPECIALLY ACROSS WESTERN NM. GIVEN HOW WARM IT IS EXPECTED TO
BE...WOULD NOT BE SURPRISED TO SEE SOME STRONG OUTFLOW WINDS FROM
THESE STORMS. OTHERWISE...HEAVY RAIN WILL BE THE MAIN THREAT.
PENDING HOW MODELS TREND TONIGHT...THE MIDNIGHT SHIFT MAY NEED TO
ISSUE A FLASH FLOOD WATCH FOR PORTIONS OF WESTERN AND CENTRAL NM.
THE ACTIVE PERIOD STILL LOOKS TO CONTINUE THROUGH MONDAY.
RELATIVELY SLOW STORM MOTIONS AND HEAVY RAIN POTENTIAL WILL
CONTINUE AS PWATS RAISE TO ABOUT 1 INCH OR BETTER ACROSS THE AREA.
SOME RELIEF STILL LOOKS TO COME ON TUESDAY AS DRIER AIR ROUNDS THE
UPPER HIGH INTO THE STATE. STILL ENOUGH MOISTURE FOR STORMS TO
DEVELOP OVER THE MOUNTAINS...BUT OVERALL STORM COVERAGE SHOULD
DECREASE SOME. COULD SEE A FEW MORE HAIL PRODUCING STORMS THOUGH
VS MAINLY RAIN.
MODELS NOW SHOWING A BACK DOOR FRONT/WIND SHIFT ON WEDNESDAY...
RATHER THAN THURSDAY...WHICH MAY RESULT IN WEDNESDAY BEING A
LITTLE MORE ACTIVE THAT THOUGHT YESTERDAY...ESPECIALLY ACROSS THE
NE. A MUCH STRONGER FRONT LOOKS TO ARRIVE NEXT FRIDAY AND
SATURDAY...AS A SHORTWAVE TROUGH SLIDES ACROSS COLORADO IN NW
FLOW. THIS WILL BE JUST IN TIME FOR 4TH OF JULY FESTIVITIES. STAY
TUNED.
34
&&
.FIRE WEATHER...
WETTING SHOWERS AND THUNDERSTORMS WILL CONTINUE TO BE ACTIVE
THROUGH THE WEEKEND INTO THE EARLY HALF OF NEXT WEEK. TEMPERATURES
WILL RANGE NEAR TO BELOW NORMAL FOLLOWING AN INCREASE IN SURFACE
MOISTURE. STORM MOTIONS WILL BE SLOW MOVING INCREASING FLASH
FLOODING POTENTIAL...ESPECIALLY EAST OF THE CENTRAL MOUNTAIN
CHAIN. THE FOUR CORNERS WILL BE THE LEAST ACTIVE FOR THE NEXT
SEVERAL DAYS. TUESDAY AND WEDNESDAY WILL SEE A SLIGHT DOWNTREND IN
STORM ACTIVITY AND UPTICK IN TEMPERATURES. ANOTHER BACK DOOR COLD
FRONT SHOULD REPLENISH MOISTURE LATER NEXT WEEK.
WETTING SHOWERS AND THUNDERSTORMS WILL CONTINUE THIS AFTERNOON INTO
THE EVENING ACROSS MUCH OF CENTRAL AND EASTERN NEW MEXICO.
THUNDERSTORM COVERAGE WILL BE HIGHER THAN PREVIOUS BECAUSE OF A BACK
DOOR FRONT SLOWLY PUSHING SOUTH/WESTWARD TOWARD THE CENTRAL MOUNTAIN
CHAIN. A DEEP SURGE IN MOISTURE WILL FOLLOW THE BACK DOOR COLD FRONT
AS IT PUSHES WESTWARD INCREASING THUNDERSTORM CHANCES WITH HEAVY
RAINFALL. GUSTY GAP WINDS WILL BE EXPECTED LATE TONIGHT WITHIN THE
CENTRAL RIO GRANDE VALLEY...ALTHOUGH THE FORECAST TIMING FOR THE GAP
WINDS WILL BE A BIT TRICKY SINCE THE FRONT IS MOVING SLOWER THAN
ANTICIPATED. STORM MOTION WILL BE SLOW MOVING FROM NORTHEAST TO
SOUTHWEST OVER THE NEXT 24 HOUR...INCREASING FLASH FLOODING
POTENTIAL FOR AREAS EAST OF THE CENTRAL MOUNTAIN CHAIN
TONIGHT...THEN EXPANDING TO CENTRAL AND WESTERN AREAS OVER THE
WEEKEND.
LOW LEVEL MOISTURE WILL CONTINUE TO PUSH TOWARD THE CONTINENTAL
DIVIDE BY SATURDAY INCREASING WET THUNDERSTORMS FOR CENTRAL AND
WESTERN NEW MEXICO. THE HIGHER THUNDERSTORM COVERAGE TREND SHOULD
CONTINUE INTO EARLY NEXT WEEK. BASED ON THE UPPER HIGH POSITION THE
STEERING FLOW SHOULD BE NORTHERLY FOR THE STORMS. TEMPERATURES WILL
BE COOLER WITH HIGHER RELATIVE HUMIDITY VALUES.
BY TUESDAY....STORMS WILL DOWNTREND A BIT BECAUSE OF DRIER MID LEVEL
AIR ROTATING AROUND THE UPPER LEVEL HIGH. THIS DRIER TREND WILL NOT
ELIMINATE STORM CHANCES. STORM CHANCES SHOULD INCREASE BY THURSDAY
DUE TO A BACK DOOR COLD FRONT.
32
&&
.AVIATION...
18Z TAF CYCLE
SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP. INITIALLY
IMPACTING THE MOUNTAINS BUT EVENTUALLY PUSHING OFF AND IMPACTS
LOWLAND SITES. TS COVERAGE WILL BE HIGHER TODAY AND THE STORMS
HAVE MORE POTENTIAL OF PRODUCING BRIEF MVFR/IFR CONDITIONS. MTN
TOP OBSCD WILL ALSO BE POSSIBLE FOR A BRIEF PERIOD OVER MOST OF
THE MTN RANGES. MOST OF THE TERMINAL SITES WILL BE IMPACTED BUT
USING VCSH/VCTS FOR MOST OF THEM UNTIL THE DEVELOPMENT BECOMES
MORE ROBUST. LVS/TCC ARE LIKELY TO BE IMPACTED BY THE HEAVIER
RAIN. GUSTY EAST WIND WILL ALSO DEVELOP AND IMPACT ABQ LATER
TODAY. SUSPECT GUSTS BETWEEN 35-40 KT BUT COULD BE SLIGHTLY HIGHER
FOR A BRIEF PERIOD. TIMING OF THE ONSET OF THIS EAST WIND IS
PRETTY TRICKY. AWW WIND SPEEDS DUE TO GUSTY EAST WIND POSSIBLE.
LOW CLOUD DEVELOPMENT ALONG THE EAST SLOPES OF THE CENTRAL MTNS
ARE POSSIBLE INCLUDING IMPACTS TO LVS BUT THE SIGNAL ISNT AS GOOD
RIGHT NOW IN THE MODELS SO WILL HOLD OFF THERE.
50
&&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 63 95 63 94 / 5 20 30 10
DULCE........................... 51 87 49 86 / 30 40 50 30
CUBA............................ 53 82 53 83 / 40 60 60 40
GALLUP.......................... 55 91 55 90 / 10 30 30 30
EL MORRO........................ 55 87 53 85 / 40 60 60 70
GRANTS.......................... 57 87 54 87 / 30 50 60 50
QUEMADO......................... 59 88 56 84 / 40 70 60 60
GLENWOOD........................ 56 90 57 87 / 40 60 60 60
CHAMA........................... 48 81 48 82 / 40 60 60 50
LOS ALAMOS...................... 60 82 59 84 / 50 70 60 60
PECOS........................... 56 79 55 81 / 70 60 90 60
CERRO/QUESTA.................... 50 74 50 76 / 60 60 60 60
RED RIVER....................... 46 67 46 69 / 70 70 60 60
ANGEL FIRE...................... 47 71 43 71 / 80 70 60 70
TAOS............................ 51 80 50 82 / 40 50 50 60
MORA............................ 52 74 51 78 / 80 80 70 60
ESPANOLA........................ 58 87 56 89 / 30 40 50 40
SANTA FE........................ 61 80 59 83 / 50 70 70 60
SANTA FE AIRPORT................ 60 85 58 87 / 50 40 60 50
ALBUQUERQUE FOOTHILLS........... 66 88 63 87 / 60 50 70 50
ALBUQUERQUE HEIGHTS............. 68 90 67 90 / 40 30 60 50
ALBUQUERQUE VALLEY.............. 66 92 64 91 / 40 30 60 40
ALBUQUERQUE WEST MESA........... 68 91 65 90 / 40 30 60 30
LOS LUNAS....................... 65 92 63 91 / 30 20 60 30
RIO RANCHO...................... 67 91 64 91 / 40 30 60 50
SOCORRO......................... 66 93 64 91 / 30 20 50 30
SANDIA PARK/CEDAR CREST......... 58 84 58 84 / 70 50 80 60
TIJERAS......................... 60 86 59 86 / 60 50 80 60
MORIARTY/ESTANCIA............... 53 85 53 85 / 70 50 80 50
CLINES CORNERS.................. 56 80 56 82 / 80 60 90 70
GRAN QUIVIRA.................... 59 83 58 82 / 60 50 70 50
CARRIZOZO....................... 62 86 61 85 / 50 40 60 30
RUIDOSO......................... 56 78 56 79 / 70 60 60 50
CAPULIN......................... 56 79 56 81 / 60 40 30 30
RATON........................... 54 81 54 84 / 70 40 30 30
SPRINGER........................ 56 81 55 85 / 70 50 30 30
LAS VEGAS....................... 53 78 53 81 / 80 60 70 40
CLAYTON......................... 60 83 61 90 / 30 30 20 20
ROY............................. 58 79 58 84 / 70 40 40 30
CONCHAS......................... 64 86 64 92 / 70 30 40 20
SANTA ROSA...................... 63 86 62 90 / 80 30 60 20
TUCUMCARI....................... 64 88 65 93 / 50 20 30 20
CLOVIS.......................... 63 83 63 88 / 50 20 40 20
PORTALES........................ 65 85 64 89 / 50 20 40 20
FORT SUMNER..................... 66 85 64 89 / 70 20 60 20
ROSWELL......................... 67 90 66 93 / 60 20 50 20
PICACHO......................... 61 83 60 86 / 70 40 50 20
ELK............................. 59 76 58 79 / 60 50 50 30
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR THE FOLLOWING ZONES...
NMZ515-523-526-528-529-532-533-537>539.
&&
$$
34
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
622 PM EDT FRI JUN 26 2015
.SYNOPSIS...
A WEAK FRONT WILL MOVE SOUTH INTO EASTERN NORTH CAROLINA THIS
EVENING, THEN MOVE BACK NORTH TONIGHT. A STRONGER COLD FRONT WILL
MOVE THROUGH SUNDAY MORNING THAT WILL BECOME STATIONARY SOUTH OF
THE REGION THROUGH MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 610 PM FRI...SEVERAL STRONG TO SEVERE STORMS MOVING THROUGH
EASTERN NORTH CAROLINA THIS EARLY EVENING. THESE WILL CONTINUE TO
EFFECT EASTERN SECTIONS OVER THE NEXT FEW HOURS. SEVERE THUNDERSTORM
WATCH HAS BEEN EXTENDED TO INCLUDE ALL COUNTIES IN FORECAST AREA AND
WATERS.
AS OF 410 PM FRIDAY...SEVERE THUNDERSTORM WATCH 361 IS NOW IN
EFFECT UNTIL 1000 PM EDT.
HIGH RESOLUTION AND GLOBAL GUIDANCE INDICATE A WEAK FRONTAL
BOUNDARY WILL SHIFT SOUTH ACROSS THE NORTHERN PORTIONS OF THE MHX
CWA LATER THIS AFTERNOON. LATEST RUNS OF THE HRRR SUGGESTS AN MCS
WILL DEVELOP ACROSS THE NORTHERN PIEDMONT AND MOVE INTO EASTERN NC
LATER THIS EVENING. 12Z NAM DOES NOT INDICATE THE MCS FEATURE BUT
INDICATES DECENT CONVECTIVE COVERAGE ASSOCIATED WITH THE FRONT
SINKING SOUTH INTO EASTERN NC. WE HAVE REACHED CONVECTIVE TEMP
ACROSS MANY INLAND LOCATIONS BUT LACK A TRIGGER AND ALSO SUFFER
FROM SUBSIDENCE IN THE WAKE OF THIS MORNINGS SHORTWAVE/SQUALL LINE
THAT MOVED THROUGH THE OBX. EXPECT CONVECTION TO DEVELOP AFTER
19-20Z DUE TO A COMBINATION OF THE FRONT, SEABREEZE, AND LEFTOVER
BOUNDARIES FROM OVERNIGHT CONVECTION. TRIED TO BETTER PINPOINT
TIMING OF CONVECTION THIS AFTERNOON AND TRENDED POPS A BIT HIGHER
FOR THE HWY 64 AND NORTH AREAS ASSOCIATED WITH THE FRONT SAGGING
INTO THE AREA. SOME ISOLATED CONVECTION BEGINNING TO DEVELOP IN
RAH CWA SLOWLY PUSHING EAST BUT STRUGGLING TO SEE MUCH DEVELOPMENT
ALONG THE SEABREEZE JUST YET. NUCAPS SOUNDINGS MIRROR THE
SIGNIFICANT INSTABILITY ACROSS EASTERN NC NOTED IN THE SPC
MESOANALYSES, WITH MUCAPE VALUES NEAR 4000 J/KG. WEAK WEST-
SOUTHWESTERLY SHEAR 25-30 KNOTS IS FORECAST TO INCREASE, ESPECIALLY
ACROSS NORTHERN PORTIONS OF THE CWA, TO 35-45 KNOTS LATE THIS
AFTERNOON AND EVENING. ANY STORMS THAT BECOME SEVERE WILL HAVE THE
POTENTIAL TO PRODUCE HAIL AND/OR DAMAGING WIND GUSTS.
A FEW SITES ARE REPORTING HEAT INDICES ABOVE 105 DEGREES F BUT
EXPECT CLOUDS AND CONVECTIVE COVERAGE IN INCREASE WHICH SHOULD
DIMINISH TEMPS AND THUS HEAT INDEX VALUES BELOW HEAT ADVISORY
THRESHOLDS.
TONIGHT...THE FRONT WILL LIFT NORTH OF THE REGION TONIGHT. TIMING
AND COVERAGE OF SHOWERS AND THUNDERSTORMS REMAINS TRICKY DUE TO
LOSS OF DAYTIME HEATING AND LIFTING MECHANISMS. WILL MAINTAIN
CHANCE POPS THROUGH LATE EVENING, THEN LIKELY POPS LATE TONIGHT AS
A MOIST SOUTHERLY FLOW OVERTAKES THE REGION WHICH WOULD SUPPORT
SLIGHTLY BETTER COVERAGE OF SHOWERS AND THUNDERSTORMS. OVERNIGHT
LOWS WILL FALL INTO THE LOW/MID 70S INLAND TO MID/UPPER 70S ALONG
THE COAST.
&&
.SHORT TERM /SATURDAY/...
AS OF 3 PM FRIDAY...WIDESPREAD SHOWERS AND THUNDERSTORMS EXPECTED
ON SATURDAY. AN UPPER TROUGH WILL CONTINUE TO DIG SOUTHEAST INTO
THE MIDWESTERN STATES AND INTO THE EASTERN CONUS. A SURFACE LOW
WILL STRENGTHEN AS IT MOVES THROUGH THE OHIO RIVER VALLEY
SATURDAY. A MOIST/MODERATE SOUTHWESTERLY FLOW WILL PERSIST DURING
THE DAY SATURDAY. A VORTMAX/SHORTWAVE EMBEDDED IN THE MEAN
NORTHEASTERLY FLOW ALOFT WILL TRAVERSE EASTERN NC DURING THE
AFTERNOON HOURS. PWATS INCREASE TO ABOVE 2 INCHES, NEARLY 2
STANDARD DEVIATIONS ABOVE NORMAL FOR JUNE. A SLIGHT RISK FOR
SEVERE STORMS CONTINUES FOR SATURDAY WITH THE MAIN THREATS OF
DAMAGING WIND GUSTS, HAIL, AND AN ISOLATED TORNADO (GIVEN AN
IMPROVING SHEAR PROFILE). MAX TEMPERATURES WILL BUILD INTO THE
UPPER 80S TO NEAR 90S INLAND WITH MID 80S ALONG THE COAST, THOUGH
TEMP FORECAST REMAINS TRICKY AS SHOWERS/CLOUDS COULD SIGNIFICANTLY
IMPACT TEMPERATURES.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
AS OF 310 PM FRIDAY...WET WEEKEND FOLLOWED BY SOME DRIER MORE
COMFORTABLE DAYS. THREAT OF RAIN RETURNS BY THE MIDDLE OF NEXT
WEEK.
SATURDAY NIGHT/SUNDAY...DEEPENING UPPER TROUGH COUPLED WITH A
GULF MOISTURE FEED PUSHING PRECIPITABLE WATER TO 2 INCHES OR
GREATER...AND A STALLED FRONTAL BOUNDARY TO OUR NORTH WILL LEAD TO
WIDESPREAD SHOWERS AND THUNDERSTORMS SATURDAY NIGHT. THE FRONT
WILL PUSH OFFSHORE WITH THE UPPER TROUGH AXIS EXITING THE COAST
DURING SUNDAY. KEPT A CHANCE OF SHOWERS/THUNDERSTORMS NEAR THE
COAST DURING SUNDAY MORNING...BUT DOWNSLOPING FLOW SHOULD QUICKLY
CLEAR THINGS OUT SUNDAY AFTERNOON. DRIER AIR FILTERS IN LEADING TO
A MUCH MORE COMFORTABLE SUNDAY WITH HIGHS IN THE 80S AND DEWPOINTS
DROPPING INTO THE 60S.
SUNDAY NIGHT THROUGH TUESDAY...SURFACE HIGH PRESSURE AND LOW UPPER
HEIGHTS LEAD TO MORE SEASONABLE WEATHER SUNDAY NIGHT THROUGH
TUESDAY WITH NO PRECIPITATION EXPECTED. TEMPERATURES WILL
GENERALLY BE IN THE MID/UPPER 80S FOR HIGHS AND MID 60S/LOW 70S
FOR LOWS...BEFORE WARMING BACK WELL INTO THE 90S BY TUESDAY.
WEDNESDAY THROUGH FRIDAY...A SIMILAR PATTERN TO THIS WEEKEND`S
PATTERN WILL SET UP FOR MID/LATE NEXT WEEK. A MID-LEVEL TROUGH
WILL DEVELOP AS HEIGHTS LOWER. COUPLED WITH A STALLED FRONTAL
BOUNDARY AND DEEP MOISTURE...EXPECT A RETURN OF RAIN CHANCES
WEDNESDAY THROUGH THURSDAY NIGHT...WITH SLIGHTLY LOWER POPS FRIDAY
AS THE UPPER TROUGH LIFTS OUT. TEMPERATURES WILL BE BACK CLOSE TO
SEASONAL NORMALS FOR LATE NEXT WEEK.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH 18Z SATURDAY/...
AS OF 130 PM FRI...VFR CONDITIONS EXPECTED DURING MUCH OF THE
PERIOD. HOWEVER...WITH SUMMER-TIME HEATING...INSTABILITY IN PLACE
AND DISTURBANCES CROSSING THE AREA...THUNDERSTORMS ARE POSSIBLE
AGAIN THIS AFTERNOON/EVENING. GIVEN THIS...EXPECT SUB-VFR
CONDITIONS COLLOCATED WITH THIS PRECIPITATION ACTIVITY. TIMING
THESE SHOWER/STORMS AND THEIR OVERALL EXTENT IS PROVING DIFFICULT
AT THIS TIME. AS OF RIGHT NOW...BKN CU FIELD IS DEVELOPING AROUND
4-5 KFT AND EXPECT CLOUD COVER TO LINGER THROUGH THE OVERNIGHT AS
ANY CONVECTIVE DEBRIS WORKS ITS WAY EASTWARD. ANTICIPATE WINDS TO
BECOME SSW OVERNIGHT.
LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 330 PM FRIDAY...WIDESPREAD SUB-VFR CONDITIONS ARE LIKELY
SATURDAY NIGHT INTO EARLY SUNDAY AS SHOWERS AND THUNDERSTORMS WILL
BE NUMEROUS. VFR RETURNS ON SUNDAY AS DOWNSLOPING DRIER AIR MOVES
IN WITH GENERALLY DRY WEATHER THROUGH TUESDAY. A CHANCE OF
SCATTERED THUNDERSTORMS RETURNS FOR WEDNESDAY...AND SOME BRIEF
PERIODS OF LATE DAY MVFR CEILINGS/VSBYS ARE POSSIBLE.
&&
.MARINE...
SHORT TERM /THROUGH SATURDAY/
AS OF 620 PM FRI...MAINLY SOUTHWEST FLOW OVER THE COASTAL WATERS
SOUTH OF FRONTAL BOUNDARY NEAR OREGON INLET WITH NORTHEASTERLY FLOW
NORTH OF THE BOUNDARY. SEAS 4 TO 5 FEET SOUTH OF THIS BOUNDARY WITH
2 TO 3 FEET NORTH OF IT. BOUNDARY EXPECT TO DROP A LITTLE FURTHER
SOUTH THIS EVENING BEFORE SHIFTING NORTH OVERNIGHT. SEVERE
THUNDERSTORM WATCH IS IN EFFECT FOR ALL THE WATERS THROUGH 10PM WITH
ASSOCIATED STORMS.
PREV DISC...AS OF 305 PM FRIDAY...LATEST SURFACE AND BUOY DATA
INDICATE MOSTLY SOUTHWESTERLY FLOW 15-20 KT WITH SEAS 3-5 FT.
CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY LEVELS THROUGH
TONIGHT DUE TO A FRONTAL BOUNDARY SHIFTING SOUTH ACROSS THE
NORTHERN/CENTRAL COASTAL WATERS. THE FRONT SHOULD ACT TO DIMINISH
THE SW GRADIENT OVER THE WATERS THROUGH TONIGHT, THEN EXPECT THE
GRADIENT TO INCREASE ON SATURDAY AS THE WEAK BOUNDARY SHIFTS NORTH
OF THE EASTERN NC WATERS. POOR BOATING CONDITIONS EXPECTED LATE
SATURDAY AS SOUTH-SOUTHWESTERLY WINDS INCREASE, BUILDING SEAS 5-8 FT
THROUGH SATURDAY NIGHT. SMALL CRAFT ADVISORIES WILL BE ISSUED FOR
MOST OF THE EASTERN NC COASTAL WATERS FOR SOUTHWESTERLY WINDS 20-30
KT AND SEAS PEAKING AT 6-9 FT FOR THE OUTER WATERS. LOCAL SWAN/NWPS
AND WAVEWATCH IN DECENT AGREEMENT FOR THE SHORT TERM, THOUGH HEDGED
CLOSER TO SWAN/NWPS FOR THE NORTHERN WATERS GIVEN ITS BETTER
PERFORMANCE IN NEAR SHORE NORTHEASTERLY FLOW.
LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 330 PM FRIDAY...SMALL CRAFT ADVISORY CONDITIONS WILL BE
ONGOING AT THE BEGINNING OF THE EXTENDED PERIOD WITH GRADIENT
BEHIND BOUNDARY TO THE NORTH AND BERMUDA HIGH PRESSURE. SOUTHWEST
WINDS OF 20 TO 25 KNOTS WITH 25 TO 30 KNOTS CENTRAL WATERS CAN BE
EXPECTED WITH SEAS AS HIGH AS 8 FEET. GUSTY WINDS CONTINUE THROUGH
SUNDAY BEFORE SUBSIDING AS A COLD FRONT EASES OFFSHORE AND WINDS
BECOME MORE W/NW BY LATE SUNDAY THEN NE AT 10 KNOTS OR LESS BY
EARLY MONDAY MORNING. THE FRONT QUICKLY WASHES OUT WITH A S/SW
WIND FLOW RESUMING MONDAY EVENING. THE GRADIENT TIGHTENS AGAIN
WEDNESDAY WITH 15 TO 20 KNOT SOUTHWEST WINDS AND SEAS BUILDING TO
AS HIGH AS 6 FEET WEDNESDAY AFTERNOON.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM TO 11 PM EDT SATURDAY FOR
AMZ136-137.
SMALL CRAFT ADVISORY FROM 2 PM SATURDAY TO NOON EDT SUNDAY FOR
AMZ135.
SMALL CRAFT ADVISORY FROM 4 PM SATURDAY TO 5 AM EDT SUNDAY FOR
AMZ130-131.
SMALL CRAFT ADVISORY FROM 2 PM SATURDAY TO 1 AM EDT MONDAY FOR
AMZ152-154.
SMALL CRAFT ADVISORY FROM 4 PM SATURDAY TO 10 PM EDT SUNDAY
FOR AMZ156-158.
SMALL CRAFT ADVISORY FROM 2 PM SATURDAY TO 8 PM EDT SUNDAY FOR
AMZ150.
&&
$$
SYNOPSIS...DAG
NEAR TERM...CGG/DAG
SHORT TERM...DAG
LONG TERM...CTC
AVIATION...CTC/LEP
MARINE...CGG/CTC/DAG
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
411 PM EDT FRI JUN 26 2015
.SYNOPSIS...
A WEAK FRONT WILL MOVE SOUTH INTO EASTERN NORTH CAROLINA THIS
EVENING, THEN MOVE BACK NORTH TONIGHT. A STRONGER COLD FRONT WILL
MOVE THROUGH SUNDAY MORNING THAT WILL BECOME STATIONARY SOUTH OF
THE REGION THROUGH MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 410 PM FRIDAY...SEVERE THUNDERSTORM WATCH 361 IS NOW IN
EFFECT UNTIL 1000 PM EDT.
HIGH RESOLUTION AND GLOBAL GUIDANCE INDICATE A WEAK FRONTAL
BOUNDARY WILL SHIFT SOUTH ACROSS THE NORTHERN PORTIONS OF THE MHX
CWA LATER THIS AFTERNOON. LATEST RUNS OF THE HRRR SUGGESTS AN MCS
WILL DEVELOP ACROSS THE NORTHERN PIEDMONT AND MOVE INTO EASTERN NC
LATER THIS EVENING. 12Z NAM DOES NOT INDICATE THE MCS FEATURE BUT
INDICATES DECENT CONVECTIVE COVERAGE ASSOCIATED WITH THE FRONT
SINKING SOUTH INTO EASTERN NC. WE HAVE REACHED CONVECTIVE TEMP
ACROSS MANY INLAND LOCATIONS BUT LACK A TRIGGER AND ALSO SUFFER
FROM SUBSIDENCE IN THE WAKE OF THIS MORNINGS SHORTWAVE/SQUALL LINE
THAT MOVED THROUGH THE OBX. EXPECT CONVECTION TO DEVELOP AFTER
19-20Z DUE TO A COMBINATION OF THE FRONT, SEABREEZE, AND LEFTOVER
BOUNDARIES FROM OVERNIGHT CONVECTION. TRIED TO BETTER PINPOINT
TIMING OF CONVECTION THIS AFTERNOON AND TRENDED POPS A BIT HIGHER
FOR THE HWY 64 AND NORTH AREAS ASSOCIATED WITH THE FRONT SAGGING
INTO THE AREA. SOME ISOLATED CONVECTION BEGINNING TO DEVELOP IN
RAH CWA SLOWLY PUSHING EAST BUT STRUGGLING TO SEE MUCH DEVELOPMENT
ALONG THE SEABREEZE JUST YET. NUCAPS SOUNDINGS MIRROR THE
SIGNIFICANT INSTABILITY ACROSS EASTERN NC NOTED IN THE SPC
MESOANALYSES, WITH MUCAPE VALUES NEAR 4000 J/KG. WEAK WEST-
SOUTHWESTERLY SHEAR 25-30 KNOTS IS FORECAST TO INCREASE, ESPECIALLY
ACROSS NORTHERN PORTIONS OF THE CWA, TO 35-45 KNOTS LATE THIS
AFTERNOON AND EVENING. ANY STORMS THAT BECOME SEVERE WILL HAVE THE
POTENTIAL TO PRODUCE HAIL AND/OR DAMAGING WIND GUSTS.
A FEW SITES ARE REPORTING HEAT INDICES ABOVE 105 DEGREES F BUT
EXPECT CLOUDS AND CONVECTIVE COVERAGE IN INCREASE WHICH SHOULD
DIMINISH TEMPS AND THUS HEAT INDEX VALUES BELOW HEAT ADVISORY
THRESHOLDS.
TONIGHT...THE FRONT WILL LIFT NORTH OF THE REGION TONIGHT. TIMING
AND COVERAGE OF SHOWERS AND THUNDERSTORMS REMAINS TRICKY DUE TO
LOSS OF DAYTIME HEATING AND LIFTING MECHANISMS. WILL MAINTAIN
CHANCE POPS THROUGH LATE EVENING, THEN LIKELY POPS LATE TONIGHT AS
A MOIST SOUTHERLY FLOW OVERTAKES THE REGION WHICH WOULD SUPPORT
SLIGHTLY BETTER COVERAGE OF SHOWERS AND THUNDERSTORMS. OVERNIGHT
LOWS WILL FALL INTO THE LOW/MID 70S INLAND TO MID/UPPER 70S ALONG
THE COAST.
&&
.SHORT TERM /SATURDAY/...
AS OF 3 PM FRIDAY...WIDESPREAD SHOWERS AND THUNDERSTORMS EXPECTED
ON SATURDAY. AN UPPER TROUGH WILL CONTINUE TO DIG SOUTHEAST INTO
THE MIDWESTERN STATES AND INTO THE EASTERN CONUS. A SURFACE LOW
WILL STRENGTHEN AS IT MOVES THROUGH THE OHIO RIVER VALLEY
SATURDAY. A MOIST/MODERATE SOUTHWESTERLY FLOW WILL PERSIST DURING
THE DAY SATURDAY. A VORTMAX/SHORTWAVE EMBEDDED IN THE MEAN
NORTHEASTERLY FLOW ALOFT WILL TRAVERSE EASTERN NC DURING THE
AFTERNOON HOURS. PWATS INCREASE TO ABOVE 2 INCHES, NEARLY 2
STANDARD DEVIATIONS ABOVE NORMAL FOR JUNE. A SLIGHT RISK FOR
SEVERE STORMS CONTINUES FOR SATURDAY WITH THE MAIN THREATS OF
DAMAGING WIND GUSTS, HAIL, AND AN ISOLATED TORNADO (GIVEN AN
IMPROVING SHEAR PROFILE). MAX TEMPERATURES WILL BUILD INTO THE
UPPER 80S TO NEAR 90S INLAND WITH MID 80S ALONG THE COAST, THOUGH
TEMP FORECAST REMAINS TRICKY AS SHOWERS/CLOUDS COULD SIGNIFICANTLY
IMPACT TEMPERATURES.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
AS OF 310 PM FRIDAY...WET WEEKEND FOLLOWED BY SOME DRIER MORE
COMFORTABLE DAYS. THREAT OF RAIN RETURNS BY THE MIDDLE OF NEXT
WEEK.
SATURDAY NIGHT/SUNDAY...DEEPENING UPPER TROUGH COUPLED WITH A
GULF MOISTURE FEED PUSHING PRECIPITABLE WATER TO 2 INCHES OR
GREATER...AND A STALLED FRONTAL BOUNDARY TO OUR NORTH WILL LEAD TO
WIDESPREAD SHOWERS AND THUNDERSTORMS SATURDAY NIGHT. THE FRONT
WILL PUSH OFFSHORE WITH THE UPPER TROUGH AXIS EXITING THE COAST
DURING SUNDAY. KEPT A CHANCE OF SHOWERS/THUNDERSTORMS NEAR THE
COAST DURING SUNDAY MORNING...BUT DOWNSLOPING FLOW SHOULD QUICKLY
CLEAR THINGS OUT SUNDAY AFTERNOON. DRIER AIR FILTERS IN LEADING TO
A MUCH MORE COMFORTABLE SUNDAY WITH HIGHS IN THE 80S AND DEWPOINTS
DROPPING INTO THE 60S.
SUNDAY NIGHT THROUGH TUESDAY...SURFACE HIGH PRESSURE AND LOW UPPER
HEIGHTS LEAD TO MORE SEASONABLE WEATHER SUNDAY NIGHT THROUGH
TUESDAY WITH NO PRECIPITATION EXPECTED. TEMPERATURES WILL
GENERALLY BE IN THE MID/UPPER 80S FOR HIGHS AND MID 60S/LOW 70S
FOR LOWS...BEFORE WARMING BACK WELL INTO THE 90S BY TUESDAY.
WEDNESDAY THROUGH FRIDAY...A SIMILAR PATTERN TO THIS WEEKEND`S
PATTERN WILL SET UP FOR MID/LATE NEXT WEEK. A MID-LEVEL TROUGH
WILL DEVELOP AS HEIGHTS LOWER. COUPLED WITH A STALLED FRONTAL
BOUNDARY AND DEEP MOISTURE...EXPECT A RETURN OF RAIN CHANCES
WEDNESDAY THROUGH THURSDAY NIGHT...WITH SLIGHTLY LOWER POPS FRIDAY
AS THE UPPER TROUGH LIFTS OUT. TEMPERATURES WILL BE BACK CLOSE TO
SEASONAL NORMALS FOR LATE NEXT WEEK.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH 18Z SATURDAY/...
AS OF 130 PM FRI...VFR CONDITIONS EXPECTED DURING MUCH OF THE
PERIOD. HOWEVER...WITH SUMMER-TIME HEATING...INSTABILITY IN PLACE
AND DISTURBANCES CROSSING THE AREA...THUNDERSTORMS ARE POSSIBLE
AGAIN THIS AFTERNOON/EVENING. GIVEN THIS...EXPECT SUB-VFR
CONDITIONS COLLOCATED WITH THIS PRECIPITATION ACTIVITY. TIMING
THESE SHOWER/STORMS AND THEIR OVERALL EXTENT IS PROVING DIFFICULT
AT THIS TIME. AS OF RIGHT NOW...BKN CU FIELD IS DEVELOPING AROUND
4-5 KFT AND EXPECT CLOUD COVER TO LINGER THROUGH THE OVERNIGHT AS
ANY CONVECTIVE DEBRIS WORKS ITS WAY EASTWARD. ANTICIPATE WINDS TO
BECOME SSW OVERNIGHT.
LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 330 PM FRIDAY...WIDESPREAD SUB-VFR CONDITIONS ARE LIKELY
SATURDAY NIGHT INTO EARLY SUNDAY AS SHOWERS AND THUNDERSTORMS WILL
BE NUMEROUS. VFR RETURNS ON SUNDAY AS DOWNSLOPING DRIER AIR MOVES
IN WITH GENERALLY DRY WEATHER THROUGH TUESDAY. A CHANCE OF
SCATTERED THUNDERSTORMS RETURNS FOR WEDNESDAY...AND SOME BRIEF
PERIODS OF LATE DAY MVFR CEILINGS/VSBYS ARE POSSIBLE.
&&
.MARINE...
SHORT TERM /THROUGH SATURDAY/
AS OF 305 PM FRIDAY...LATEST SURFACE AND BUOY DATA INDICATE
MOSTLY SOUTHWESTERLY FLOW 15-20 KT WITH SEAS 3-5 FT. CONDITIONS
SHOULD REMAIN BELOW SMALL CRAFT ADVISORY LEVELS THROUGH TONIGHT
DUE TO A FRONTAL BOUNDARY SHIFTING SOUTH ACROSS THE NORTHERN/CENTRAL
COASTAL WATERS. THE FRONT SHOULD ACT TO DIMINISH THE SW GRADIENT
OVER THE WATERS THROUGH TONIGHT, THEN EXPECT THE GRADIENT TO
INCREASE ON SATURDAY AS THE WEAK BOUNDARY SHIFTS NORTH OF THE
EASTERN NC WATERS. POOR BOATING CONDITIONS EXPECTED LATE SATURDAY
AS SOUTH-SOUTHWESTERLY WINDS INCREASE, BUILDING SEAS 5-8 FT
THROUGH SATURDAY NIGHT. SMALL CRAFT ADVISORIES WILL BE ISSUED FOR
MOST OF THE EASTERN NC COASTAL WATERS FOR SOUTHWESTERLY WINDS
20-30 KT AND SEAS PEAKING AT 6-9 FT FOR THE OUTER WATERS. LOCAL
SWAN/NWPS AND WAVEWATCH IN DECENT AGREEMENT FOR THE SHORT TERM,
THOUGH HEDGED CLOSER TO SWAN/NWPS FOR THE NORTHERN WATERS GIVEN
ITS BETTER PERFORMANCE IN NEAR SHORE NORTHEASTERLY FLOW.
LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 330 PM FRIDAY...SMALL CRAFT ADVISORY CONDITIONS WILL BE
ONGOING AT THE BEGINNING OF THE EXTENDED PERIOD WITH GRADIENT
BEHIND BOUNDARY TO THE NORTH AND BERMUDA HIGH PRESSURE. SOUTHWEST
WINDS OF 20 TO 25 KNOTS WITH 25 TO 30 KNOTS CENTRAL WATERS CAN BE
EXPECTED WITH SEAS AS HIGH AS 8 FEET. GUSTY WINDS CONTINUE THROUGH
SUNDAY BEFORE SUBSIDING AS A COLD FRONT EASES OFFSHORE AND WINDS
BECOME MORE W/NW BY LATE SUNDAY THEN NE AT 10 KNOTS OR LESS BY
EARLY MONDAY MORNING. THE FRONT QUICKLY WASHES OUT WITH A S/SW
WIND FLOW RESUMING MONDAY EVENING. THE GRADIENT TIGHTENS AGAIN
WEDNESDAY WITH 15 TO 20 KNOT SOUTHWEST WINDS AND SEAS BUILDING TO
AS HIGH AS 6 FEET WEDNESDAY AFTERNOON.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM TO 11 PM EDT SATURDAY FOR
AMZ136-137.
SMALL CRAFT ADVISORY FROM 2 PM SATURDAY TO NOON EDT SUNDAY FOR
AMZ135.
SMALL CRAFT ADVISORY FROM 4 PM SATURDAY TO 5 AM EDT SUNDAY FOR
AMZ130-131.
SMALL CRAFT ADVISORY FROM 2 PM SATURDAY TO 1 AM EDT MONDAY FOR
AMZ152-154.
SMALL CRAFT ADVISORY FROM 4 PM SATURDAY TO 10 PM EDT SUNDAY
FOR AMZ156-158.
SMALL CRAFT ADVISORY FROM 2 PM SATURDAY TO 8 PM EDT SUNDAY FOR
AMZ150.
&&
$$
SYNOPSIS...DAG
NEAR TERM...DAG
SHORT TERM...DAG
LONG TERM...CTC
AVIATION...CTC/LEP
MARINE...CTC/DAG
AREA FORECAST DISCUSSION
NWS RALEIGH NC
259 PM EDT FRI JUN 26 2015
.SYNOPSIS...AN UPPER LEVEL TROUGH DIGGING SOUTHEAST INTO THE OHIO
VALLEY TODAY WILL DEEPEN ALONG THE EASTERN SEABOARD OVER THE WEEKEND.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 300 PM FRIDAY...
THINGS HAVING A REALLY HARD TIME GETTING GOING THIS AFTERNOON AS
SUBSIDENCE BEHIND THIS MORNINGS WAVE OF CONVECTION ACROSS THE VA
BORDER IS DELAYING THE ONSET OF AFTERNOON SHOWERS AND THUNDERSTORMS.
CONVECTIVE ALLOWING MODELS ALREADY HEAD SHOWERS IN THE TRIAD BY 18Z
WHICH IS NOT CLOSE TO HAPPENING AT THIS POINT AND RAP MODEL
VORTICITY NOW SHOWS ANY SHORTWAVE ACTIVITY REMAINING NORTHEAST OF
THE AREA FOR THE MOST PART. LOOKING AT VARIOUS PARAMETERS ON THE SPC
MESOSCALE ANALYSIS THERE ARE STILL SEVERAL THINGS STILL GOING WELL
FOR THE CHANCES FOR CONVECTION THIS AFTERNOON INCLUDING INCREASING
SHEAR FROM THE NORTH...DECENT INSTABILITY...AND UPWARDS OF 2 INCHES
OF PRECIPITABLE WATER. THE PROBLEM WE MAY HAVE HOWEVER...IS GETTING
THINGS TO LINE UP. WHILE SHEAR IS BEST IN THE NORTH...DCAPE IS BEST
IN THE SOUTH. WHILE THE BEST VORTICITY WOULD BE IN THE
NORTHEAST...THE STRONGEST LAPSE RATES WILL BE IN THE SOUTHWEST. WITH
THE SHORTWAVE MOVING OFF TO THE NORTHEAST...ANY FOCUS FOR CONVECTION
WILL BE ALONG THE RESIDUAL FRONT AND A POTENTIAL DIFFERENTIAL
HEATING BOUNDARY. SURFACE OBS CURRENTLY SHOW 80S IN THE NORTHEAST
WITH LOW 90S ACROSS THE US 64 CORRIDOR BUT MID 90S ACROSS THE
SOUTHERN TIER OF COUNTIES.
HERE ARE THE TAKEAWAYS. FIRST...CONVECTION THIS AFTERNOON IS STILL
POSSIBLE AND SEVERE WEATHER IS ALSO POSSIBLE AS SUGGESTED BY THE SPC
SLIGHT RISK AREA. HOWEVER...COVERAGE AND STRENGTH OF STORMS SHOULD
NOT BE AS STRONG AS YESTERDAY. THE EVOLUTION OF THE CUMULUS FIELD ON
SATELLITE SUGGEST THAT THE FRONTAL BOUNDARY WILL BE THE MOST LIKELY
SPOT FOR CONVECTION THIS AFTERNOON WHICH IS ROUGHLY ALONG THE US 64
CORRIDOR. MAIN THREATS TODAY WILL BE FROM WIND AND POTENTIALLY SOME
HAIL AS A SECONDARY THREAT AS WELL AS FLOODING IN ANY SLOW MOVING OR
TRAINING CELLS. TIMING WILL BE LATER THIS AFTERNOON INTO THE EVENING.
FOR TONIGHT...ATTENTION WILL TURN TO THE WEST AND AN APPROACHING
COLD FRONTAL SYSTEM. AS THE SYSTEM MOVES CLOSER TO THE AREA...A PRE-
FRONTAL TROUGH WILL FIRST MOVE THROUGH THE AREA DURING THE OVERNIGHT
AREAS FROM SOUTHWEST TO NORTHEAST. THIS COULD BRING A ROUND OF
CONVECTION INTO THE TRIAD AROUND 6Z AND PUSHING THROUGH THE
NORTHEASTERN PART OF THE CWA BY 9Z. AFTER THIS MOVES
THROUGH...EXPECT A LULL IN PRECIPITATION THROUGH SUNRISE. LOWS
MAINLY IN THE LOWER 70S WITH SOME FOG/STRATUS POSSIBLE BEFORE
DAYBREAK.
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...
CENTRAL NC IS UNDER A SLIGHT RISK FOR SEVERE WEATHER ON SATURDAY AS
AN UPPER LEVEL TROUGH BEGINS TO DIG INTO THE SOUTHEAST AND A SURFACE
LOW AMPLIFIES OVER THE OHIO VALLEY. THE ATTENDANT COLD FRONT IS
PROGGED TO SWING THROUGH THE CWA ON SATURDAY EVENING. PRIOR TO THAT
HAPPENING...DIURNAL DESTABILIZATION AND INCREASING MOISTURE
TRANSPORT WILL HELP CONVECTION TO BEGIN DEVELOPING ACROSS THE CWA BY
EARLY AFTERNOON. WHAT WILL START AS SCATTERED SHOWERS AND
THUNDERSTORMS WILL GRADUALLY BECOME MORE ORGANIZED INTO CLUSTERS AND
SMALL LINE SEGMENTS WHICH WILL BEGIN TO MOVE EAST AS FORCING FROM
THE FRONT GETS CLOSER. BY EVENING...THE MAIN COLD FRONT WILL BEGIN
TO MOVE THROUGH THE AREA SUPPORTING A QUASI-LINEAR CONVECTIVE SYSTEM
THAT WILL BE CAPABLE OF PRODUCING SEVERE WEATHER...MOST LIKELY IN
THE FORM OF DAMAGING WINDS ALONG BOWING SEGMENTS OF THE LINE.
CONVECTIVE ALLOWING MODELS HAVE BEEN CONSISTENTLY SHOWING A SIMILAR
EVOLUTION OF THE CONVECTION AND THIS IS SUPPORTED BY THE LARGER
SCALE MODELS SO CONFIDENCE IS FAIRLY HIGH AT THIS TIME. IN ADDITION
TO DAMAGING WINDS...SECONDARY THREATS WILL BE FROM LARGE HAIL AND
POTENTIALLY A BRIEF TORNADO...MOST LIKELY ALONG THE LINE OF
CONVECTION. THE SYSTEM WILL MOVE THROUGH FAIRLY QUICKLY SO FLOODING
DOES NOT LOOK PARTICULARLY LIKELY BUT URBAN AREAS AND PLACES WHERE
ANTECEDENT CONDITIONS ARE FAIRLY WET COULD BECOME SUBJECT TO
FLOODING.
TIMING OF THE SYSTEM SHOULD HAVE CONVECTION STARTING ACROSS THE CWA
AROUND 18Z...WITH THE MAIN FRONTAL BOUNDARY MOVING THROUGH THE TRIAD
AROUND 00Z ON SUNDAY WITH THE TRIANGLE AFFECTED JUST BEFORE MIDNIGHT
AND OUT OF THE EASTERN PORTION OF THE AREA BY 6Z ON SUNDAY. WITH
MORE CLOUD COVER BY AFTERNOON...HIGHS ON SATURDAY WILL ONLY GET INTO
THE MID 80S ACROSS THE NORTH TO NEAR 90 IN THE SOUTH. LOWS ON SUNDAY
MORNING WILL BE DEPENDENT UPON THE TIMING OF THE FRONT WITH THE
TRIAD MOST LIKELY IN THE LOWER 60S TO LOWER 70S IN THE EAST.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 1240 PM FRIDAY...
A LINGERING SHOWER IS POSSIBLE IN THE FAR SOUTHEASTERN CWFA SUNDAY
MORNING...OTHERWISE COOLER AND DRIER AIR WILL FILTER IN RAPIDLY
BEHIND THE FRONT. HIGHS WILL TOP OUT MOSTLY IN THE MID 80S...A
COUPLE OF DEGREES BELOW NORMAL. AN UPPER TROF IN THE WAKE OF THIS
SYSTEM WILL SETTLE OVER THE EASTERN CONUS AND PERSIST FOR THE
REMAINDER OF THE WEEK.
MONDAY LOOKS DRY AND SEASONABLE...WITH LEE SURFACE TROF SETTING UP
THE PREDOMINANTLY WESTERLY FLOW. HIGHS WILL BEGIN THE INEVITABLE
CREEP UPWARDS...REACHING THE MID TO UPPER 80S AFTER MORNING LOWS
FROM 60 TO 65. WARMING CONTINUES TUESDAY WITH HIGHS IN THE UPPER 80S
TO LOWER 90S...AND THE SURFACE REFLECTION OF AN INITIAL SHORT WAVE
DIGGING INTO THE UPPER TROF WILL MOVE ACROSS THE AREA TUESDAY NIGHT.
MOISTURE WILL BE LIMITED...BUT INSTABILITY WILL BE SUFFICIENT FOR AT
LEAST WIDELY SCATTERED CONVECTION INTO THE EVENING.
A SECOND FRONT NUDGES SOUTH AND STALLS IN THE VICINITY OF THE
CAROLINAS ON WEDNESDAY...WITH A SERIES OF DISTURBANCES IN THE
NORTHWEST FLOW PROVIDING US WITH A HIGH CONFIDENCE IN THE OCCURRENCE
OF CONVECTION...BUT LOW CONFIDENCE IN THE TIMING OTHER THAN COVERAGE
WHICH WILL BE MAXIMIZED DURING FAVORABLE DIURNAL HEATING. HIGHS
WEDNESDAY THROUGH FRIDAY WILL PROBABLY BE A SHADE WARMER THAN
NORMAL...UPPER 80S NORTH TO LOW 90S ACROSS THE SOUTHERN TIER.
MORNING LOWS WILL BE WITHIN A DEGREE OR TWO OF 70.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 200 PM FRIDAY
24 HOUR TAF PERIOD: VFR CONDITIONS ACROSS THE AREA AS EARLIER SHOWER
ACTIVITY HAS DISSIPATED AND LEFT SOME SUBSIDENCE IN ITS WAKE. AS A
RESULT...CONVECTION HAS BEEN A LITTLE SLOW TO GET GOING THIS
AFTERNOON. NOT SURE IF RECOVERY WILL BEGIN EARLY ENOUGH TO THREATEN
THE TRIAD AS THE NEXT WAVE MOVES THROUGH SO HAVE TAKEN THUNDER OUT
OF THE TAFS THERE FOR THIS AFTERNOON BUT KEPT IT IN AT KRDU AND KRWI
AS WE WILL CONTINUE TO DESTABILIZE THIS AFTERNOON AND SHOULD REALIZE
CONVECTION A BIT LATER. PARAMETERS ARE STILL GOOD FOR SEVERE WX SO
THERE IS A RISK FOR SOME STRONG WIND GUSTS IN THE VICINITY OF
SHOWERS AND THUNDERSTORMS. OTHERWISE WINDS WILL BE LIGHT AND
VARIABLE STRATOCUMULUS ACROSS THE AREA.
OVERNIGHT TONIGHT A FIRST WAVE AHEAD OF AN APPROACHING COLD FRONT
WILL MOVE THROUGH DURING THE EARLY MORNING HOURS...BRINING A CHANCE
FOR SHOWERS AND THUNDERSTORMS TO ALL SITES BEFORE MOVING NORTHEAST
OUT OF THE AREA. A BREAK IN PRECIPITATION NEAR SUNRISE WILL GIVE WAY
TO MUCH BETTER CHANCES FOR SHOWERS...THUNDERSTORMS...A GOOD CHANCE
OF SEVERE WEATHER SATURDAY AFTERNOON IN THE WEST THROUGH THE EARLY
MORNING HOURS ON SUNDAY IN THE EAST.
LONG TERM: CONDITIONS SHOULD RETURN TO VFR ON SUNDAY WITH THE FIRST
HALF OF THE WORK WEEK LOOKING VERY NICE WITH A MORE UNSETTLED
PATTERN RETURN FOR THE SECOND HALF OF THE WEEK.
&&
.CLIMATE...
REC
DAY MAX YR
RDU RECORDS
06/26 102 1952
GSO RECORDS
06/26 102 1914
FAY RECORDS
06/26 101 1951
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...NP
NEAR TERM...ELLIS
SHORT TERM...ELLIS
LONG TERM...MLM
AVIATION...ELLIS
CLIMATE...BLAES
AREA FORECAST DISCUSSION
NWS BISMARCK ND
504 PM CDT FRI JUN 26 2015
.UPDATE...
ISSUED AT 504 PM CDT FRI JUN 26 2015
CONFINED POPS TO THE MORE DENSE CU FIELDS...SOUTHWEST AND
EAST...ALSO WHERE RADAR RETURNS ARE AT. OTHERWISE UPDATES WERE
MINOR FOR THIS FORECAST ISSUANCE.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 238 PM CDT FRI JUN 26 2015
THUNDERSTORM POTENTIAL THIS AFTERNOON THROUGH TONIGHT AND A WARM
SATURDAY HIGHLIGHT THE SHORT TERM FORECAST.
THE 18 UTC RAP ANALYSIS DEPICTS 800-1500 J/KG OF ML CAPE FROM THE
JAMES RIVER VALLEY THROUGH THE TURTLE MOUNTAINS AND INTO THE
SOURIS BASIN...WITH DEEP LAYER SHEAR ON THE ORDER OF 20-25 KTS.
RADAR TRENDS THROUGH 1940 UTC DEPICT ISOLATED CONVECTION
INITIATING ACROSS THESE AREAS...WITH A FEW WEAK IMPULSES EMBEDDED
IN NORTHWEST FLOW ALOFT. CANNOT RULE OUT A STRONG STORM WITH SMALL
HAIL AND GUSTY WINDS...HOWEVER...ANY SEVERE THREAT AT THIS TIME
APPEARS LOW. THESE AFTERNOON STORMS ARE EXPECTED TO FADE WITH
SUNSET. ANOTHER ROUND OF STORMS ASSOCIATED WITH A WAVE ACROSS
CENTRAL SASKATCHEWAN THIS AFTERNOON MAY PROPAGATE INTO NORTHERN
NORTH DAKOTA TONIGHT. THESE STORMS ARE EXPECTED TO BE NON-SEVERE.
ACROSS SOUTH CENTRAL NORTH DAKOTA AND THE JAMES RIVER VALLEY...A
SIMILAR FOG SETUP TONIGHT IS EXPECTED WHICH PRODUCED FOG THIS
MORNING FOR THESE AREAS. THUS...ADDED FOG FOR LATE TONIGHT INTO
SATURDAY MORNING FOR THESE LOCATIONS.
FOR SATURDAY...A WARM DAY IS FORECAST AHEAD OF A WEAK COLD FRONT
THAT WILL PROPAGATE ACROSS WESTERN AND CENTRAL NORTH DAKOTA FROM
SOUTHERN CANADA THROUGH THE AFTERNOON. WITH GOOD MIXING AND
INSOLATION...WIDESPREAD HIGHS IN THE UPPER 80S TO LOWER 90S ARE
EXPECTED...ON THE WARMER EDGE OF THE 12 UTC DETERMINISTIC AND
STATISTICAL SUITES.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 238 PM CDT FRI JUN 26 2015
DETERMINISTIC AND ENSEMBLE MODELS INDICATE MAINLY DRY CONDITIONS TO
BEGIN THE LONG TERM PERIOD. ALTHOUGH AN ISOLATED THUNDERSTORM CAN
NOT BE COMPLETELY RULED OUT DUE TO DAYTIME HEATING. UPPER LEVEL
RIDGING WILL BE THE DOMINANT FEATURE IN THE FORECAST SUNDAY AND
MONDAY.
SHORTWAVE ENERGY BEGINS TO MAKE ITS WAY THROUGH THE MEAN UPPER
LEVEL RIDGE BEGINNING MONDAY NIGHT. WILL UTILIZE THE MODEL BLEND
IN REGARDS TO POPS WHICH BRINGS SMALL CHANCES OF THUNDERSTORMS
ACROSS AT LEAST PARTS OF WESTERN AND CENTRAL NORTH DAKOTA MONDAY
NIGHT THROUGH FRIDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 238 PM CDT FRI JUN 26 2015
VFR CONDITIONS ARE EXPECTED TODAY WITH SURFACE HIGH PRESSURE.
ISOLATED THUNDERSTORMS MAY BE POSSIBLE IN THE KJMS VICINITY THIS
AFTERNOON...AND KMOT THIS AFTERNOON INTO TONIGHT. FOG WILL ONCE
AGAIN BE POSSIBLE TONIGHT FOR KBIS/KJMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...AYD
LONG TERM...TWH
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
252 PM CDT FRI JUN 26 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 238 PM CDT FRI JUN 26 2015
THUNDERSTORM POTENTIAL THIS AFTERNOON THROUGH TONIGHT AND A WARM
SATURDAY HIGHLIGHT THE SHORT TERM FORECAST.
THE 18 UTC RAP ANALYSIS DEPICTS 800-1500 J/KG OF ML CAPE FROM THE
JAMES RIVER VALLEY THROUGH THE TURTLE MOUNTAINS AND INTO THE
SOURIS BASIN...WITH DEEP LAYER SHEAR ON THE ORDER OF 20-25 KTS.
RADAR TRENDS THROUGH 1940 UTC DEPICT ISOLATED CONVECTION
INITIATING ACROSS THESE AREAS...WITH A FEW WEAK IMPULSES EMBEDDED
IN NORTHWEST FLOW ALOFT. CANNOT RULE OUT A STRONG STORM WITH SMALL
HAIL AND GUSTY WINDS...HOWEVER...ANY SEVERE THREAT AT THIS TIME
APPEARS LOW. THESE AFTERNOON STORMS ARE EXPECTED TO FADE WITH
SUNSET. ANOTHER ROUND OF STORMS ASSOCIATED WITH A WAVE ACROSS
CENTRAL SASKATCHEWAN THIS AFTERNOON MAY PROPAGATE INTO NORTHERN
NORTH DAKOTA TONIGHT. THESE STORMS ARE EXPECTED TO BE NON-SEVERE.
ACROSS SOUTH CENTRAL NORTH DAKOTA AND THE JAMES RIVER VALLEY...A
SIMILAR FOG SETUP TONIGHT IS EXPECTED WHICH PRODUCED FOG THIS
MORNING FOR THESE AREAS. THUS...ADDED FOG FOR LATE TONIGHT INTO
SATURDAY MORNING FOR THESE LOCATIONS.
FOR SATURDAY...A WARM DAY IS FORECAST AHEAD OF A WEAK COLD FRONT
THAT WILL PROPAGATE ACROSS WESTERN AND CENTRAL NORTH DAKOTA FROM
SOUTHERN CANADA THROUGH THE AFTERNOON. WITH GOOD MIXING AND
INSOLATION...WIDESPREAD HIGHS IN THE UPPER 80S TO LOWER 90S ARE
EXPECTED...ON THE WARMER EDGE OF THE 12 UTC DETERMINISTIC AND
STATISTICAL SUITES.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 238 PM CDT FRI JUN 26 2015
DETERMINISTIC AND ENSEMBLE MODELS INDICATE MAINLY DRY CONDITIONS TO
BEGIN THE LONG TERM PERIOD. ALTHOUGH AN ISOLATED THUNDERSTORM CAN
NOT BE COMPLETELY RULED OUT DUE TO DAYTIME HEATING. UPPER LEVEL
RIDGING WILL BE THE DOMINANT FEATURE IN THE FORECAST SUNDAY AND
MONDAY.
SHORTWAVE ENERGY BEGINS TO MAKE ITS WAY THROUGH THE MEAN UPPER
LEVEL RIDGE BEGINNING MONDAY NIGHT. WILL UTILIZE THE MODEL BLEND
IN REGARDS TO POPS WHICH BRINGS SMALL CHANCES OF THUNDERSTORMS
ACROSS AT LEAST PARTS OF WESTERN AND CENTRAL NORTH DAKOTA MONDAY
NIGHT THROUGH FRIDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 238 PM CDT FRI JUN 26 2015
VFR CONDITIONS ARE EXPECTED TODAY WITH SURFACE HIGH PRESSURE.
ISOLATED THUNDERSTORMS MAY BE POSSIBLE IN THE KJMS VICINITY THIS
AFTERNOON...AND KMOT THIS AFTERNOON INTO TONIGHT. FOG WILL ONCE
AGAIN BE POSSIBLE TONIGHT FOR KBIS/KJMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AYD
LONG TERM...TWH
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
101 PM CDT FRI JUN 26 2015
.UPDATE...
ISSUED AT 1255 PM CDT FRI JUN 26 2015
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE...AS THE 15-17
UTC HRRR ITERATIONS CONTINUE TO SUPPORT AFTERNOON ISOLATED TO
SCATTERED THUNDERSTORM ACTIVITY FROM THE TURTLE MOUNTAINS THROUGH
THE JAMES RIVER VALLEY AND POINTS EAST...WHERE CUMULUS FIELDS
CONTINUE TO BUILD ON VISIBLE SATELLITE.
UPDATE ISSUED AT 829 AM CDT FRI JUN 26 2015
GIVEN A TIME LAGGED ENSEMBLE OF THE 09-11 UTC HRRR ITERATIONS AND
A CONSENSUS OF THE 00 UTC WRF-ARW/NMM AND 06 UTC NAM...DECREASED
THE OVERALL MENTION OF ISOLATED THUNDERSTORMS ACROSS CENTRAL
NORTH DAKOTA TODAY...CONFINING THE MENTION TO PRIMARILY THE TURTLE
MOUNTAINS THROUGH THE JAMES RIVER VALLEY.
UPDATE ISSUED AT 639 AM CDT FRI JUN 26 2015
MAIN ADJUSTMENT TO THE FORECAST WAS TO ADD ISOLATED SHOWERS IN THE
JAMES RIVER VALLEY THIS MORNING. KBIS WSR-88D SHOWS A FEW SHOWERS
IN THAT AREA...AND THE LATEST HRRR HINTS THAT THEY COULD PERSIST
FOR A FEW HOURS. PATCHY FOG WAS LEFT IN PLACE WITH A FEW SPOTS
ACROSS WESTERN AND CENTRAL NORTH DAKOTA REPORTING REDUCED
VISIBILITIES. DID NOT ADJUST POPS FOR THIS AFTERNOON WITH ISOLATED
TO SCATTERED SHOWERS / THUNDERSTORMS STILL SUPPORTED IN THE HRRR
AND 26.06Z NAM.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CDT FRI JUN 26 2015
THE LATEST WATER VAPOR IMAGERY DEPICTS A NORTHWEST FLOW INTO
NORTH DAKOTA WITH THE NEXT SIGNIFICANT UPSTREAM SHORTWAVE TROUGH
WORKING THROUGH CENTRAL BRITISH COLUMBIA. THIS SHORTWAVE TROUGH
WILL MOVE EAST THEN PIVOT SOUTHEAST AS IT SLIDES INTO SOUTH CENTRAL
MANITOBA 12Z SATURDAY. IN RESPONSE...A SURFACE LOW PRESSURE AND
ASSOCIATED COLD FRONT WILL EMERGE OVER SOUTHERN ALBERTA/SASKATCHEWAN
INTO NORTHERN MONTANA FRIDAY EVENING/NIGHT. THE COLD FRONT WILL
ENTER NORTHWESTERN NORTH DAKOTA AROUND 12Z SATURDAY. IN ADVANCE OF
THIS SYSTEM FOR TODAY(FRIDAY)...A COUPLE OF SUBTLE SHORTWAVES
STRETCHING FROM SOUTHERN/EASTERN SASKATCHEWAN INTO CENTRAL NORTH
DAKOTA WILL HELP PRODUCE ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS DURING THE AFTERNOON/EVENING. CAPE/SHEAR VALUES
REMAIN WEAK AND THE LATEST HIGH RESOLUTION MODELS...ARW WEST/NMM
WEST/HRRR...PORTRAY ISOLATED TO SCATTERED SHOWERS/THUNDERSTORMS...MAINLY
FROM THE TURTLE MOUNTAINS SOUTH INTO THE JAMES RIVER VALLEY. THE
GLOBAL MODELS EXTEND PRECIPITATION CHANCES ACROSS CENTRAL NORTH
DAKOTA WITH THE FAR WEST REMAINING DRY. USED A BLEND OF THE HIGH
RESOLUTION AND GLOBAL SUITE FOR POPS TODAY...AS THE SHORTWAVES
INTERACT WITH THE WEAK INSTABILITY ALREADY IN PLACE THIS AFTERNOON
AND EVENING. THE ISOLATED SHOWERS/THUNDERSTORMS WILL CONTINUE
FRIDAY NIGHT AS A WEAK LOW LEVEL/850MB JET BRIEFLY DEVELOPS FRIDAY
EVENING ADVECTING IN MOISTURE AHEAD OF THE AFOREMENTIONED
SHORTWAVE TROUGH AND SURFACE FRONT. HOWEVER NOT EXPECTING ANY
SEVERE WEATHER AT THIS TIME...AND SPC CONVECTIVE OUTLOOK
HIGHLIGHTS GENERAL THUNDERSTORMS FRIDAY/FRIDAY NIGHT. HIGH
TEMPERATURES FRIDAY AFTERNOON WILL BE IN THE LOW TO MID 80S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 308 AM CDT FRI JUN 26 2015
A WEAK COLD FRONT MOVING ACROSS THE NORTHERN PLAINS COULD BRING A
CHANCE OF THUNDERSTORMS ON SATURDAY. THE MAIN CHANCES SHOULD BE IN
THE EASTERN PART OF THE FORECAST AREA WITH THE BOUNDARY REACHING
THAT AREA SATURDAY AFTERNOON DURING PEAK HEATING. THE THUNDERSTORM
CHANCES ARE EXPECTED TO DIMINISH IN THE EVENING AS THE BOUNDARY
EXITS THE REGION.
DRY WEATHER IS EXPECTED SUNDAY AND MONDAY WITH H5 HEIGHTS BUILDING
ACROSS NORTH DAKOTA. BY MONDAY NIGHT...THE FIRST IN A SERIES OF
UPPER WAVES MOVES ACROSS IN NORTHWESTERLY FLOW ALOFT. WILL FOLLOW
THE MODEL BLEND IN REGARDS TO POPS WHICH BRINGS SMALL CHANCES OF
THUNDERSTORMS ACROSS AT LEAST PARTS OF WESTERN AND CENTRAL NORTH
DAKOTA FROM MONDAY NIGHT AND BEYOND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1255 PM CDT FRI JUN 26 2015
VFR CONDITIONS ARE EXPECTED TODAY WITH SURFACE HIGH PRESSURE.
ISOLATED THUNDERSTORMS MAY BE POSSIBLE IN THE KJMS VICINITY THIS
AFTERNOON. FOG WILL ONCE AGAIN BE POSSIBLE TONIGHT FOR KBIS/KJMS.
GIVEN UNCERTAINTY...WILL LEAVE THE MENTION OUT FOR NOW.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...KS
LONG TERM...CK
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS MEDFORD OR
235 PM PDT FRI JUN 26 2015
.DISCUSSION...DISCUSSION...THE LATEST VISIBLE IMAGE IS STARTING TO
SHOW SOME CU DEVELOP OVER THE CASCADES...SISKIYOUS...EASTERN
SIKSYOU...MODOC AND HIGHER TERRAIN IN LAKE AND KLAMATH COUNTY. THE
SPC MESOSCALE ANALYSIS SHOWS CAPE VALUES INCREASING ALONG THE
CASCADES AND WESTERN SIKSYOU COUNTY THROUGH SOUTHWEST OREGON.
INTERESTING IS THE CIN VALUES HAVE TRENDED LOWER IN THE LAST FEW
HOURS. THE SOUNDING PUT OUR CONVECTIVE TEMPERATURE AT 93 DEGREES
AND IT WAS NOT MUCH LONGER AFTER WE REACHED AND EXCEEDED THAT IS
WHEN THE CU HAS STARTED TO POP UP. THE LATEST HRRR REFLECTIVITY
MODEL PUTS MOST OF THE RETURNS ALONG AND EAST OF THE CASCADES AND
A FEW IN SOUTHWEST OREGON. THE LATEST RAP SHOWS A SIMILAR
SOLUTION, BUT WITH MORE "QPF" IN SOUTHWEST OREGON. ALSO THE RAP
SHOWS A SHORTWAVE MOVING NORTHWEST INTO SOUTHWEST OREGON EARLY
THIS EVENING AND WITH CONDITIONS ALREADY UNSTABLE WITH INCREASING
MID LEVEL MOISTURE, COULD SET THE TABLE FOR ISOLATED THUNDERSTORMS
IN THIS AREA. MEANWHILE INSTABILITY WILL BE GREATER ALONG THE
CASCADES AND SISKIYOUS...SO WE COULD SEE MORE FREQUENT
THUNDERSTORMS IN THESE AREAS. UNFORTUNATELY THE MODEL SOUNDINGS
HAVE AN INVERTED "V" PROFILE WHICH MEANS THAT STORMS COULD PRODUCE
LITTLE OR NO PRECIPITATION, SO WE`LL KEEP DRY THUNDERSTORMS IN THE
FORECAST. OF NOTE SPC HAS A MARGINAL RISK IN THE CENTER OF OUR CWA
AND THE POTENTIAL FOR SCATTERED DRY THUNDERSTORMS FOR A GOOD CHUNK
OF OUR AREA TONIGHT. OF BIG CONCERN WILL BE THE POTENTIAL FOR NEW
STARTS FROM LIGHTNING. THIS WILL BE ADDRESSED IN MORE DETAIL IN
THE FORE WEATHER SECTION.
TODAY AND SATURDAY WILL BE THE HOTTEST DAYS WITH RECORD HIGHS LIKELY
TO BE SET. THE FORECAST HAS BEEN CONSISTENT IN EXPECTING VALLEY
HIGHS DURING THE NEXT TWO DAYS OF 95 TO 110 DEGREES ON THE WEST SIDE
OF THE CASCADES THIS AFTERNOON AND 92 TO 102 ON THE EAST SIDE. THE
ONLY THING THAT COULD LIMIT THE AMOUNT OF HEATING SATURDAY AND
SUNDAY WILL BE CLOUD COVER...EVEN THEN WE`LL BE HOT, BUT NOT AS HOT
AS TODAY.
PWATS WILL GRADUALLY INCREASE TO 0.75 TO 1.00 INCHES. THE LEAST
AMOUNT OF RAINFALL WITH THUNDERSTORMS WILL BE IN THOSE THAT DEVELOP
SOUTH AND EAST OF SOUTHWEST OREGON.
COVERAGE OF STORMS WILL INCREASE DURING THE EVENING WITH A PRIMARY
FOCUS FOR NORTHWARD MOVING THUNDERSTORMS FROM THE FOOTHILLS OF THE
CASCADES AND CASCADES ITSELF AND SISKIYOUS. HOWEVER THE RAP SHOWS A
SHORTWAVE MOVING INTO SOUTHWEST OREGON THIS EVENING, SO THERE COULD
BE A SECONDARY FOCUS IN JOSEPHINE...CURRY...COOS AND PARTS OF
DOUGLAS COUNTY. THESE STORMS WILL BE MOVING AT 10 TO 15 KNOTS.
EMBEDDED SHORTWAVES IN THE SOUTHERLY FLOW ALOFT ARE EXPECTED TO KEEP
THUNDERSTORMS GOING OVERNIGHT INTO SATURDAY MORNING WITH THE HIGHEST
PROBABILITY ALONG THE CASCADES.
THUNDERSTORMS CONTINUE SATURDAY AND THERE IS A BETTER CHANCE WE
COULD GET SOME WETTING RAINS FROM THIS, BUT THEY COULD BE FASTER
MOVING. WE EXPECT A GREATER COVERAGE OF THUNDERSTORMS SATURDAY
OVERING A GOOD PORTION OF THE CWA, PEAKING IN THE AFTERNOON AND
EARLY EVENING.
THERE IS CONCERN FOR ANOTHER SURGE IN MID LEVEL MOISTURE AND
INSTABILITY SATURDAY NIGHT INTO SUNDAY. THE GFS AND EC ARE IN FAIRLY
GOOD AGREEMENT SHOWING ANOTHER SURGE OF MID LEVEL MOISTURE AND
SHORTWAVES MOVING INTO SOUTHWEST OREGON AS THE UPPER TROUGH MOVES
NORTH ALONG THE CALIFORNIA COAST. AT THE SAME TIME 850 LI`S WILL GET
INTO THE NEGATIVE TERRITORY. SO THERE IS CONCERN WE COULD SEE
ANOTHER ROUND OF NOCTURNAL STORMS IN PARTS OF
JOSEPHINE...JACKSON...CURRY...COOS AND DOUGLAS COUNTY AND CASCADES
AND SISKIYOUS SATURDAY NIGHT INTO SUNDAY MORNING. THEREFORE HAVE
INCREASED POPS IN THESE AREAS. PWATS ARE EXPECTED TO BE HIGHER, SO
WE THINK STORMS WILL PRODUCE SOME RAINFALL. HOWEVER 700-500MB WIND
SPEED IS EXPECTED TO BE BETWEEN 20-25 KTS, SO THEY WILL BE FASTER
MOVING.
THE MODELS ARE IN FAIRLY GOOD AGREEMENT WITH THE TIMING OF THE
TROUGH AXIS SUNDAY. IT WILL STILL BE TO OUR SOUTH SUNDAY, BUT THE
MID LEVELS WILL GRADUALLY DRY OUT IN SOUTHWEST OREGON AND WESTERN
SISKIYOU COUNTY LATE SUNDAY AFTERNOON...THEREFORE WE COULD BE
LOOKING AT ANOTHER ACTIVE DAY WITH SLOW IMPROVEMENT IN THE ABOVE
MENTIONED AREAS LATE SUNDAY AFTERNOON. BY SUNDAY NIGHT, THE FOCUS
FOR THUNDERSTORMS WILL SHIFT EAST WITH THE BEST CHANCE FOR STORMS
ALONG AND EAST OF THE CASCADES.
THE TROUGH AXIS WILL MOVE NORTHEAST SUNDAY NIGHT INTO MONDAY AND THE
FOCUS FOR THUNDERSTORMS WILL SHRINK AND BE MAINLY CONFINED TO
KLAMATH AND LAKE COUNTY. IT LOOKS LIKE WE COULD CATCH A BREAK IN THE
ACTION TUESDAY AS WE GET A MORE STABLE SOUTHWEST FLOW. I LEFT IN A
SLIGHT CHANCE FOR THUNDERSTORMS IN THE SOUTHEAST PORTION OF THE
FORECAST AREA, BUT THERE IS PLENTY OF DRYING AT THE MID LEVELS, SO
WOULD NOT BE SURPRISED IF WE DON`T GET ANYTHING.
THE MODELS SHOW THE RIDGE RE BUILDING WESTWARD BEYOND TUESDAY, BUT
THE HIGHEST MID LEVEL MOISTURE AND INSTABILITY SHOULD BE MOSTLY
ALONG AND EAST OF THE CASCADES, THUS HAVE TRIMMED BACK THE POPS AND
THREAT OF THUNDERSTORMS TO MODOC AND SOUTHEAST LAKE AND KLAMATH
COUNTY. -PETRUCELLI
&&
.AVIATION...FOR THE 26/18Z TAF CYCLE...LOW CLOUDS WILL CONTINUE TO
HUG THE COAST NORTH OF CAPE BLANCO WITH MAINLY IFR CONDITIONS...AND
OCCASIONAL SCATTERING TO VFR CONDITIONS. NORTH BEND SHOULD BE IN AND
OUT OF THE CEILINGS DURING THE MORNING...AND IN THE AFTERNOON THE
TERMINAL IS MORE LIKELY TO BE SOCKED IN...REMAINING THAT WAY
OVERNIGHT. ELSEWHERE VFR CONDITIONS WILL PREVAIL.
LATE THIS AFTERNOON INTO THE EVENING ISOLATED THUNDERSTORMS ARE
EXPECTED ALONG AND NEAR THE OREGON CASCADES...THE UPPER KLAMATH
BASIN...AND WESTERN SISKIYOU COUNTY. THE BEST CHANCE OF
THUNDERSTORMS IS IN THE 00-06Z TIME FRAME FOR THIS TAF CYCLE AT KLMT
AND KRBG. THESE STORMS ARE EXPECTED TO BE HIGH-BASED, DRY, AND
THEREFORE COULD CONTAIN GUSTY OUTFLOW WINDS AND POSSIBLY ISOLATED
MICROBURSTS. SK/SPILDE
&&
.MARINE...UPDATED 200 PM PDT FRIDAY 26 JUNE 2015...A THERMAL TROUGH
WILL BRING GALE FORCE NORTH WINDS SOUTH OF CAPE BLANCO THIS
AFTERNOON AND EVENING WITH VERY STEEP WIND WAVE DOMINATED SEAS. AS
IS TYPICAL WITH THERMAL TROUGH WIND PATTERNS...CONFIDENCE IS ONLY
MODERATE ON EXACTLY HOW CLOSE TO SHORE THE GALES REACH...WITH THE
FORECAST REFLECTING GALES BEYOND 10 NM FROM SHORE TODAY. THE THERMAL
TROUGH WILL WEAKEN AND BOTH WINDS AND SEAS ARE EXPECTED TO LOWER
THIS WEEKEND. THUNDERSTORMS ARE POSSIBLE TONIGHT INTO SATURDAY
MORNING WITHIN 10 NM FROM SHORE. THE THERMAL TROUGH WILL THEN
STRENGTHEN AGAIN MONDAY AND TUESDAY WITH CONDITIONS AT LEAST
HAZARDOUS TO SMALL CRAFT. STRONGEST WINDS AND SEAS WILL AGAIN BE
SOUTH OF CAPE BLANCO. /FB
&&
.FIRE WEATHER...UPDATED 200 PM PDT FRIDAY 26 JUNE 2015...ONLY MINOR
CHANGES TO THE AREAS COVERED BY THE RED FLAG WARNING THROUGH THE
WEEKEND. THE CONVECTIVE TEMPERATURE HAS FINALLY BEEN REACHED WITH
CUMULUS DEVELOPING FROM THE SOUTH AS THE CAP OVER THE REGION IS
BEING BROKEN. WIDESPREAD INSTABILITY IS OVER THE REGION BUT WITH THE
STRONGEST THETA E CONVERGENCE OVER WESTERN SISKIYOU COUNTY...THE
MOUNT SHASTA AREA AND UP THE CASCADES AND THEN DOWN THE RIDGES
BETWEEN 624 AND 625 THIS SHOULD BE WHERE THE MOST CONVECTION WILL
DEVELOP. THE 700 MB WINDS ARE FROM THE SSE AND WILL BE BORDERLINE
STRENGTH TO PUSH THE THUNDERSTORMS THAT DO DEVELOP OFF OF THE HIGHER
TERRAIN AND INTO THE WEST SIDE OF OREGON. WITH THE DRY LAYER BENEATH
AT LOWER LEVEL THE BASES OF THE STORMS SHOULD GENERALLY BE ABOVE TEN
THOUSAND FEET WITH MUCH OF THE PRECIPITATION EVAPORATING BEFORE
REACHING THE GROUND EARLY ON IN THE AFTERNOON THROUGH EARLY EVENING.
ELEVATED INSTABILITY REMAINS OVERNIGHT WITH A STRONG SHORT WAVE
MOVING THROUGH OVERNIGHT. WITH THIS A CONTINUATION OF THUNDERSTORMS
OVERNIGHT TONIGHT SEEMS A GOOD POSSIBILITY. THE MOISTURE FLOW
CONTINUES TO POUR INTO THE REGION WITH PRECIPITABLE WATER VALUES
INCREASING TO A LITTLE OVER 1.2 INCHES. THERE SHOULD BE ENOUGH
CLEARING AFTER THE SHORT WAVE BRINGS CONVECTION THROUGH THE REGION
AROUND 6-9Z TO ALLOW FOR SUFFICIENT SURFACE HEATING TO REACH THE
LEVEL OF INSTABILITY INDICATED AND MOST OF THE REGION FROM THE
COASTAL RANGES ACROSS THE EAST SIDE SHOULD BE AT LEAST CLOSE TO SOME
CONVECTION TOMORROW AS WELL. TOMORROW NIGHT WILL ALSO SEE THE
COMBINATION OF ELEVATED CONVECTION WITH A SHORT WAVE MOVING THROUGH
THE AREA...BRINGING ANOTHER NIGHT OF AT LEAST ISOLATED
THUNDERSTORMS. THE PATTERN CONTINUES SUNDAY...BUT A DRY MID LAYER
MOVES INTO THE WEST SIDE WITH 700-500 RH IN THE 20S INHIBITING
THUNDERSTORM DEVELOPMENT IN THAT AREA. THE OVERALL PATTERN REMAINS
THROUGH MUCH OF NEXT WEEK...WITH ADJUSTMENTS TO THE AREAS OF
THUNDERSTORMS BEING THE MAIN ADJUSTER TO CONFIDENCE. -SVEN
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR... RED FLAG WARNING UNTIL 11 PM PDT SUNDAY FOR ORZ615>625.
HEAT ADVISORY UNTIL 5 AM PDT SUNDAY FOR ORZ023.
HEAT ADVISORY UNTIL 5 AM PDT SUNDAY FOR ORZ024-026.
CA...RED FLAG WARNING UNTIL 11 PM PDT SUNDAY FOR CAZ280>282-284-285.
HEAT ADVISORY UNTIL 5 AM PDT SUNDAY FOR CAZ080-081.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 PM PDT THIS EVENING FOR
PZZ350-356-370-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 AM PDT SATURDAY
FOR PZZ350-356.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 AM PDT SATURDAY
FOR PZZ370-376.
GALE WARNING UNTIL 11 PM PDT THIS EVENING FOR PZZ376.
HAZARDOUS SEAS WARNING UNTIL 11 PM PDT THIS EVENING FOR PZZ376.
$$
AREA FORECAST DISCUSSION
NWS MEDFORD OR
1027 AM PDT FRI JUN 26 2015
.UPDATED AVIATION DISCUSSION.
.DISCUSSION...CURRENT VISIBLE IMAGE SHOWS CLEAR SKIES WITH SOME
LIGHT HAZE FROM THE FIRES IN CALIFORNIA MOVING NORTHWEST INTO THE
AREA AS THE UPPER FLOW HAS NOT BECOME SOUTH TO SOUTHEAST. MARINE
STRATUS REMAIN NORTH OF CAPE BLANCO AND IN THE COQUILLE VALLEY,
BUT THAT WILL BURN OFF IN THE NEXT FEW HOURS. THE WATER VAPOR
IMAGE SHOWS A WEAK UPPER LOW OFF THE CALIFORNIA COAST AND MOISTURE
ALREADY STARTING TO MOVE NORTH INTO CENTRAL NEVADA. THIS WILL
CONTINUE TO MOVE NORTH TO NORTHWEST DURING THE DAY AND WE`LL START
TO SEE CUMULUS DEVELOPING OVER THE CASCADES AND NORTHERN CAL
AROUND MIDDAY. HOWEVER THE ATMOSPHERE IS EXPECTED TO BE RATHER DRY
AND THE MID LEVEL MOISTURE IS NOT EXPECTED TO INCREASE UNTIL LATER
THIS AFTERNOON, THUS HAVE REMOVED ISOLATED THUNDERSTORMS FOR LATE
MORNING AND AFTERNOON. HOWEVER THEY ARE STILL A CONCERN STARTING
MID AFTERNOON. SOME GUIDANCE SUGGEST THE BEST CHANCE FOR STORMS
MAY END UP OVER THE CASCADES AND EASTSIDE, BUT FIND THIS SUSPECT
GIVEN WE`LL STILL BE IN A MOIST SOUTH TO SOUTHEAST FLOW AND THE
RAP SHOWS PVA MOVING THROUGH SOUTHWEST OREGON IN THE EVENING WITH
850 LI`S IN THE NEGATIVE. ALSO MID LEVEL LAPSE RATES ARE EXPECTED
TO INCREASE AND MODEL SOUNDINGS SHOW ENOUGH INSTABILITY TO KEEP
ISOLATED STORMS IN THE FORECAST TONIGHT WEST OF THE CASCADES.
IT STILL LOOKS LIKE SATURDAY WILL BE THE MOST ACTIVE WITH A GOOD
CHUNK OF THE AREA UNDER THE THREAT OF STORMS WITH MORE FREQUENT
STORMS POSSIBLE. THE BULK OF THE ACTION WILL GRADUALLY SHIFT EAST
SUNDAY AS THE UPPER TROUGH MOVES NORTH SQUEEZING THE RIDGE DOWN A
LITTLE. -PETRUCELLI
&&
.AVIATION...FOR THE 26/18Z TAF CYCLE...LOW CLOUDS WILL CONTINUE TO
HUG THE COAST NORTH OF CAPE BLANCO WITH MAINLY IFR CONDITIONS...AND
OCCASIONAL SCATTERING TO VFR CONDITIONS. NORTH BEND SHOULD BE IN AND
OUT OF THE CEILINGS DURING THE MORNING...AND IN THE AFTERNOON THE
TERMINAL IS MORE LIKELY TO BE SOCKED IN...REMAINING THAT WAY
OVERNIGHT. ELSEWHERE VFR CONDITIONS WILL PREVAIL.
LATE THIS AFTERNOON INTO THE EVENING ISOLATED THUNDERSTORMS ARE
EXPECTED ALONG AND NEAR THE OREGON CASCADES...THE UPPER KLAMATH
BASIN...AND WESTERN SISKIYOU COUNTY. THE BEST CHANCE OF
THUNDERSTORMS IS IN THE 00-06Z TIME FRAME FOR THIS TAF CYCLE AT KLMT
AND KRBG. THESE STORMS ARE EXPECTED TO BE HIGH-BASED, DRY, AND
THEREFORE COULD CONTAIN GUSTY OUTFLOW WINDS AND POSSIBLY ISOLATED
MICROBURSTS. SK/SPILDE
&&
.MARINE....MARINE...UPDATED 900 AM PDT FRIDAY 26 JUNE 2015...A THERMAL
TROUGH WILL BRING GALE FORCE NORTH WINDS SOUTH OF CAPE BLANCO
TODAY WITH VERY STEEP WIND WAVE DOMINATED SEAS. AS IS TYPICAL WITH
THERMAL TROUGH WIND PATTERNS...CONFIDENCE IS ONLY MODERATE ON
EXACTLY HOW CLOSE TO SHORE THE GALES REACH...WITH THE FORECAST
REFLECTING GALES BEYOND 10 NM FROM SHORE TODAY. THE THERMAL TROUGH
WILL WEAKEN AND BOTH WINDS AND SEAS ARE EXPECTED TO LOWER THIS
WEEKEND. THUNDERSTORMS ARE POSSIBLE TONIGHT INTO SATURDAY MORNING
WITHIN 10 NM FROM SHORE. THE THERMAL TROUGH WILL THEN STRENGTHEN
AGAIN MONDAY AND TUESDAY WITH CONDITIONS AT LEAST HAZARDOUS TO
SMALL CRAFT. STRONGEST WINDS AND SEAS WILL AGAIN BE SOUTH OF CAPE
BLANCO. SK/SPILDE
&&
FIRE WEATHER...UPDATED 400 AM PDT FRIDAY 26 JUNE 2015...HAVE MADE
NO CHANGES WITH RESPECT TO THE RED FLAG WARNING (RFWMFR) HEADLINES
IN PLACE ACROSS THE AREA BEGINNING LATER THIS AFTERNOON. MODELS
CONTINUE TO SHOW MOISTURE INCREASING IN THE SOUTH TO SOUTHEAST FLOW
DEVELOPING ALOFT IN A CORRIDOR BETWEEN AN UPPER LOW OFFSHORE AND THE
MID LEVEL RIDGE CENTERED OVER THE GREAT BASIN. THIS IS A FAVORABLE
THUNDERSTORM PATTERN AND THIS CORRIDOR IS AIMED RIGHT OVER SW
OREGON/NORCAL, WHERE ISOLATED TO SCATTERED THUNDERSTORMS ARE
EXPECTED TO DEVELOP LATER THIS AFTERNOON AND EVENING. THIS PATTERN
WILL PERSIST FRIDAY NIGHT THROUGH MUCH OF THE WEEKEND AS THE UPPER
LOW SLOWLY MOVES NORTHWARD ALONG THE CALIFORNIA COAST.
CONFIDENCE ON THE EXACT LOCATION OF STORMS REMAINS FAIRLY LOW AS MID
AND UPPER LEVEL SUPPORT FOR STORMS (SHORTWAVES) IS WEAK, BUT WITH
STRONG HEATING AND THE RESULTING INSTABILITY OVER ABNORMALLY DRY
FUELS ACROSS A LARGE PART OF THE AREA (NEAR-RECORD DRYNESS ALONG THE
COAST)...THE THREAT FOR ABUNDANT LIGHTNING IS A BIG CONCERN FOR
INITIAL ATTACK. STORMS SHOULD INITIATE OVER THE HIGHER TERRAIN THIS
AFTERNOON, THEN PROPAGATE NORTHWESTWARD WITH TIME THIS EVENING AND
OVERNIGHT. A STRONG MOISTURE GRADIENT WILL EXIST ALONG THE CASCADES.
STORMS OVER THE EAST SIDE SHOULD BE FAIRLY DRY, WHERE PWS ARE
GENERALLY LESS THAN 0.75 OF AN INCH. PWS OF 1.00-1.25 INCHES EXIST
ALONG AND WEST OF THE CASCADES WHERE STORMS THAT DEVELOP SHOULD BE
COMPARABLY WETTER. ANY STORMS WILL HAVE THE ABILITY TO PRODUCE GUSTY
OUTFLOWS THAT COULD CAUSE NEW FIRE STARTS TO SPREAD QUICKLY.
BY SATURDAY AND SATURDAY NIGHT, ADDITIONAL SHORT WAVE ACTIVITY WILL
MOVE NORTH-NORTHWESTWARD INTO THE AREA AND MOISTURE SHOULD BE
ADEQUATE FOR MOSTLY WET STORMS. WE STILL EXPECT SATURDAY TO BE THE
MOST ACTIVE DAY (AT LEAST IN TERMS OF COVERAGE OF STORMS). BY
SUNDAY, THE MODELS SUGGEST THE STRONGEST SHORT WAVE WILL MOVE
THROUGH THE AREA. BUT THE AREA OF GREATEST INSTABILITY WILL SLOWLY
SHIFT EASTWARD, SO AREAS ALONG AND EAST OF THE CASCADES WILL BE THE
AREAS THAT LIKELY SEE THE MOST COVERAGE OF STORMS. FIRE ZONES 615
AND 618 SHOULD BE IN THE CLEAR, WHILE ISOLATED STORMS MAY STILL FORM
INLAND OVER THE WEST SIDE. IT WILL BE A CLOSE CALL FOR FIRE ZONE
619.
THE RIDGE AXIS SHIFTS EAST MONDAY AS THE UPPER TROUGH AXIS MOVES
THROUGH AND THUNDERSTORM THREAT SHOULD BE MOSTLY CONFINED TO
PORTIONS OF FIRE ZONES 624 AND 625. SPILDE
&&
.PREV DISCUSSION... /ISSUED 0850 AM PDT FRI JUN 26 2015/
UPDATED MARINE DISCUSSION.
DISCUSSION...A HOT AND UNSTABLE AIR MASS WILL PERSIST OVER THE
REGION DURING THE NEXT WEEK. LOW PRESSURE OFFSHORE FROM CALIFORNIA
AND HIGH PRESSURE CENTERED IN THE GREAT BASIN ARE THE MAIN UPPER
LEVEL FEATURES AFFECTING OUR WEATHER IN THE SHORT TERM WITH THAT
STRONG RIDGING LIKELY TO PERSIST THROUGH THE WEEK.
TODAY AND SATURDAY WILL BE THE HOTTEST DAYS WITH RECORD HIGHS LIKELY
TO BE SET. BUT, THE FOLLOWING FIVE DAYS WILL NOT BE THAT MUCH
COOLER. THE FORECAST HAS BEEN CONSISTENT IN EXPECTING VALLEY HIGHS
DURING THE NEXT TWO DAYS OF 95 TO 110 DEGREES ON THE WEST SIDE OF
THE CASCADES THIS AFTERNOON AND 92 TO 102 ON THE EAST SIDE.
THE OTHER MAIN FOCUS OF THE FORECAST IS THE DEVELOPMENT OF
THUNDERSTORMS WITH THE POTENTIAL FOR LIGHTNING TO CAUSE NEW FIRES.
ATMOSPHERIC MOISTURE LEVELS WILL GRADUALLY INCREASE WITH
PRECIPITABLE WATER AMOUNTS THAT WERE AT 0.50 TO 0.75 INCHES
YESTERDAY TO RISE TO 0.75 TO 1.00 INCHES TODAY. THE LEAST AMOUNT
OF RAINFALL WITH THUNDERSTORMS WILL BE IN THOSE THAT DEVELOP SOUTH
AND EAST OF SOUTHWEST OREGON. AN EARLY AFTERNOON THUNDERSTORM
CANNOT BE COMPLETELY RULED OUT, BUT THERE IS GOOD MODEL AGREEMENT
BETWEEN THE NAM AND THE SREF AND RAP SHORT TERM MODELS THAT THE
FIRST THUNDERSTORMS WILL DEVELOP AROUND 3 PM OVER THE HIGHER
TERRAIN FROM WESTERN SISKIYOU COUNTY TO THE SISKIYOU MOUNTAINS AND
CASCADES EASTWARD. COVERAGE OF STORMS WILL INCREASE DURING THE
EVENING WITH A PRIMARY FOCUS FOR NORTHWARD MOVING THUNDERSTORMS
FROM THE FOOTHILLS OF THE CASCADES (IN EASTERN PORTIONS OF JACKSON
AND DOUGLAS COUNTIES) EASTWARD. THAT WILL NOT BE THE EXCLUSIVE
LOCATION OF THUNDERSTORMS, JUST THE LIKELY FOCUS. THESE STORMS
WILL BE MOVING AT 10 TO 15 KNOTS. EMBEDDED SHORTWAVES IN THE
SOUTHERLY FLOW ALOFT ARE EXPECTED TO KEEP THUNDERSTORMS GOING
OVERNIGHT INTO SATURDAY MORNING WITH THE HIGHEST PROBABILITY ALONG
THE CASCADES. THERE IS UNCERTAINTY IN THE TRACK AND STRENGTH OF
SHORTWAVES AS THE GFS HAS A FOCUS DURING THE EVENING HOURS BEFORE
LIFTING THE MAJORITY OF ACTIVITY INTO NORTHERN OREGON WHILE THE
NAM SOLUTION WOULD ACTUALLY INCREASE THE NUMBER OF THUNDERSTORMS
IN OUR AREA DURING THE OVERNIGHT HOURS WHILE SPREADING THEM IN A
SOUTHEAST RATHER THAN SOUTH FLOW ALOFT TO THE COAST AND COASTAL
WATERS.
THUNDERSTORMS ON SATURDAY WILL PRODUCE MORE RAINFALL BUT THEY WILL
ALSO BE FASTER MOVING AT 15 TO 25 KNOTS. THUNDERSTORM COVERAGE IS
EXPECTED TO BE AT ITS PEAK DURING SATURDAY AFTERNOON AND EVENING.
THE PERSISTENT PATTERN WILL ONCE AGAIN PRODUCE NOCTURNAL
THUNDERSTORMS SATURDAY NIGHT INTO SUNDAY MORNING.
THERE IS UNCERTAINTY IN THE TIMING AND TRACK OF THE OFFSHORE LOW.
THE NAM IS FASTER THAN THE GFS BUT BOTH HAVE IT MOVING NORTH TO
THE SOUTHERN OREGON COAST ON SUNDAY. THIS WILL BRING IN SLIGHTLY
COOLER AIR AND EVENTUALLY KICK THE CONVECTIVE ACTIVITY TO THE
EAST WITH WEST SIDE OF THE CASCADES FOCUS OF THUNDERSTORMS ON
SUNDAY MORNING SHIFTING TO THE EAST SIDE FOR SUNDAY EVENING INTO
MONDAY. THUNDERSTORMS ON SUNDAY WILL HAVE A HIGHER PROBABILITY OF
PRODUCING SEVERE WIND GUSTS. THE TROUGH WITH A MUCH DRIER AIR
MASS WILL BE IN PLACE OVER THE PACIFIC NORTHWEST ON MONDAY. THUS,
A SLIGHT CHANCE OF THUNDERSTORMS WILL BE NEARLY LIMITED TO ONLY
LAKE AND MODOC COUNTIES. MONDAY NIGHT SHOULD TRANSPIRE WITHOUT
THUNDERSTORMS.
RIDGING FROM THE GREAT BASIN IS EXPECTED TO REBUILD INTO OUR AREA
TUESDAY FOR THE START OF ANOTHER WARMING TREND INTO THURSDAY.
THIS WILL ALSO SEND HIGHER AMOUNTS OF MOISTURE INTO THE EAST SIDE
ON TUESDAY THAT WILL EXPAND FARTHER WEST...TO THE WEST SIDE ON
WEDNESDAY FOR ANOTHER EPISODE OF A SLIGHT CHANCE OF AFTERNOON AND
EVENING THUNDERSTORMS. THE PROBABILITY WILL BE THE LOWEST FOR THE
COAST AND DOUGLAS COUNTY.
FORECAST UNCERTAINTY INCREASES BEYOND WEDNESDAY AS THE ECMWF MODEL
INDICATES A STRONG TROUGH MOVING INTO THE PACIFIC NORTHWEST WILL
FINALLY CHANGE THE PATTERN AND BRING SOME COOLING FOR THE END OF
THE WEEK, BUT THE GFS IS PERSISTENT AND LEAVES THE HOT GREAT
BASIN RIDGE IN COMMAND. FOR NOW, WE WILL LEAN TOWARD PERSISTENCE.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR... RED FLAG WARNING FROM 5 PM THIS AFTERNOON TO 11 PM PDT SUNDAY
FOR ORZ615>625.
HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 5 AM PDT SUNDAY FOR
ORZ023.
HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 5 AM PDT SUNDAY FOR
ORZ024-026.
CA...RED FLAG WARNING FROM 5 PM THIS AFTERNOON TO 11 PM PDT SUNDAY
FOR CAZ280-281-284-285.
HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 5 AM PDT SUNDAY FOR
CAZ080-081.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 PM PDT THIS EVENING FOR
PZZ350-356-370-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 AM PDT SATURDAY
FOR PZZ350-356.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 AM PDT SATURDAY
FOR PZZ370-376.
GALE WARNING UNTIL 11 PM PDT THIS EVENING FOR PZZ376.
HAZARDOUS SEAS WARNING UNTIL 11 PM PDT THIS EVENING FOR PZZ376.
$$
AREA FORECAST DISCUSSION
NWS MEDFORD OR
936 AM PDT FRI JUN 26 2015
.DISCUSSION...CURRENT VISIBLE IMAGE SHOWS CLEAR SKIES WITH SOME
LIGHT HAZE FROM THE FIRES IN CALIFORNIA MOVING NORTHWEST INTO THE
AREA AS THE UPPER FLOW HAS NOT BECOME SOUTH TO SOUTHEAST. MARINE
STRATUS REMAIN NORTH OF CAPE BLANCO AND IN THE COQUILLE VALLEY,
BUT THAT WILL BURN OFF IN THE NEXT FEW HOURS. THE WATER VAPOR
IMAGE SHOWS A WEAK UPPER LOW OFF THE CALIFORNIA COAST AND MOISTURE
ALREADY STARTING TO MOVE NORTH INTO CENTRAL NEVADA. THIS WILL
CONTINUE TO MOVE NORTH TO NORTHWEST DURING THE DAY AND WE`LL START
TO SEE CUMULUS DEVELOPING OVER THE CASCADES AND NORTHERN CAL
AROUND MIDDAY. HOWEVER THE ATMOSPHERE IS EXPECTED TO BE RATHER DRY
AND THE MID LEVEL MOISTURE IS NOT EXPECTED TO INCREASE UNTIL LATER
THIS AFTERNOON, THUS HAVE REMOVED ISOLATED THUNDERSTORMS FOR LATE
MORNING AND AFTERNOON. HOWEVER THEY ARE STILL A CONCERN STARTING
MID AFTERNOON. SOME GUIDANCE SUGGEST THE BEST CHANCE FOR STORMS
MAY END UP OVER THE CASCADES AND EASTSIDE, BUT FIND THIS SUSPECT
GIVEN WE`LL STILL BE IN A MOIST SOUTH TO SOUTHEAST FLOW AND THE
RAP SHOWS PVA MOVING THROUGH SOUTHWEST OREGON IN THE EVENING WITH
850 LI`S IN THE NEGATIVE. ALSO MID LEVEL LAPSE RATES ARE EXPECTED
TO INCREASE AND MODEL SOUNDINGS SHOW ENOUGH INSTABILITY TO KEEP
ISOLATED STORMS IN THE FORECAST TONIGHT WEST OF THE CASCADES.
IT STILL LOOKS LIKE SATURDAY WILL BE THE MOST ACTIVE WITH A GOOD
CHUNK OF THE AREA UNDER THE THREAT OF STORMS WITH MORE FREQUENT
STORMS POSSIBLE. THE BULK OF THE ACTION WILL GRADUALLY SHIFT EAST
SUNDAY AS THE UPPER TROUGH MOVES NORTH SQUEEZING THE RIDGE DOWN A
LITTLE. -PETRUCELLI
&&
.AVIATION....AVIATION...FOR THE 26/12Z TAF CYCLE...LOW CLOUDS WILL
CONTINUE ALONG THE NORTH COAST WITH IFR TO LIFR CIGS THIS MORNING
GRADUALLY RISING TO MVFR THIS AFTERNOON. ELSEWHERE VFR CONDITIONS
WILL PREVAIL.
LATE THIS AFTERNOON INTO THE EVENING ISOLATED THUNDERSTORMS ARE
EXPECTED ALONG AND NEAR THE OREGON CASCADES...THE UPPER KLAMATH
BASIN...AND WESTERN SISKIYOU COUNTY. THE BEST CHANCE OF
THUNDERSTORMS IS IN THE 00-06Z TIME FRAME FOR THIS TAF CYCLE AT KLMT
AND KRBG. THESE STORMS ARE EXPECTED TO BE HIGH-BASED, DRY, AND
THEREFORE COULD CONTAIN GUSTY OUTFLOW WINDS AND POSSIBLY ISOLATED
MICROBURSTS. BTL/SPILDE
&&
.MARINE....MARINE...UPDATED 900 AM PDT FRIDAY 26 JUNE 2015...A THERMAL
TROUGH WILL BRING GALE FORCE NORTH WINDS SOUTH OF CAPE BLANCO
TODAY WITH VERY STEEP WIND WAVE DOMINATED SEAS. AS IS TYPICAL WITH
THERMAL TROUGH WIND PATTERNS...CONFIDENCE IS ONLY MODERATE ON
EXACTLY HOW CLOSE TO SHORE THE GALES REACH...WITH THE FORECAST
REFLECTING GALES BEYOND 10 NM FROM SHORE TODAY. THE THERMAL TROUGH
WILL WEAKEN AND BOTH WINDS AND SEAS ARE EXPECTED TO LOWER THIS
WEEKEND. THUNDERSTORMS ARE POSSIBLE TONIGHT INTO SATURDAY MORNING
WITHIN 10 NM FROM SHORE. THE THERMAL TROUGH WILL THEN STRENGTHEN
AGAIN MONDAY AND TUESDAY WITH CONDITIONS AT LEAST HAZARDOUS TO
SMALL CRAFT. STRONGEST WINDS AND SEAS WILL AGAIN BE SOUTH OF CAPE
BLANCO. SK/SPILDE
&&
FIRE WEATHER...UPDATED 400 AM PDT FRIDAY 26 JUNE 2015...HAVE MADE
NO CHANGES WITH RESPECT TO THE RED FLAG WARNING (RFWMFR) HEADLINES
IN PLACE ACROSS THE AREA BEGINNING LATER THIS AFTERNOON. MODELS
CONTINUE TO SHOW MOISTURE INCREASING IN THE SOUTH TO SOUTHEAST FLOW
DEVELOPING ALOFT IN A CORRIDOR BETWEEN AN UPPER LOW OFFSHORE AND THE
MID LEVEL RIDGE CENTERED OVER THE GREAT BASIN. THIS IS A FAVORABLE
THUNDERSTORM PATTERN AND THIS CORRIDOR IS AIMED RIGHT OVER SW
OREGON/NORCAL, WHERE ISOLATED TO SCATTERED THUNDERSTORMS ARE
EXPECTED TO DEVELOP LATER THIS AFTERNOON AND EVENING. THIS PATTERN
WILL PERSIST FRIDAY NIGHT THROUGH MUCH OF THE WEEKEND AS THE UPPER
LOW SLOWLY MOVES NORTHWARD ALONG THE CALIFORNIA COAST.
CONFIDENCE ON THE EXACT LOCATION OF STORMS REMAINS FAIRLY LOW AS MID
AND UPPER LEVEL SUPPORT FOR STORMS (SHORTWAVES) IS WEAK, BUT WITH
STRONG HEATING AND THE RESULTING INSTABILITY OVER ABNORMALLY DRY
FUELS ACROSS A LARGE PART OF THE AREA (NEAR-RECORD DRYNESS ALONG THE
COAST)...THE THREAT FOR ABUNDANT LIGHTNING IS A BIG CONCERN FOR
INITIAL ATTACK. STORMS SHOULD INITIATE OVER THE HIGHER TERRAIN THIS
AFTERNOON, THEN PROPAGATE NORTHWESTWARD WITH TIME THIS EVENING AND
OVERNIGHT. A STRONG MOISTURE GRADIENT WILL EXIST ALONG THE CASCADES.
STORMS OVER THE EAST SIDE SHOULD BE FAIRLY DRY, WHERE PWS ARE
GENERALLY LESS THAN 0.75 OF AN INCH. PWS OF 1.00-1.25 INCHES EXIST
ALONG AND WEST OF THE CASCADES WHERE STORMS THAT DEVELOP SHOULD BE
COMPARABLY WETTER. ANY STORMS WILL HAVE THE ABILITY TO PRODUCE GUSTY
OUTFLOWS THAT COULD CAUSE NEW FIRE STARTS TO SPREAD QUICKLY.
BY SATURDAY AND SATURDAY NIGHT, ADDITIONAL SHORT WAVE ACTIVITY WILL
MOVE NORTH-NORTHWESTWARD INTO THE AREA AND MOISTURE SHOULD BE
ADEQUATE FOR MOSTLY WET STORMS. WE STILL EXPECT SATURDAY TO BE THE
MOST ACTIVE DAY (AT LEAST IN TERMS OF COVERAGE OF STORMS). BY
SUNDAY, THE MODELS SUGGEST THE STRONGEST SHORT WAVE WILL MOVE
THROUGH THE AREA. BUT THE AREA OF GREATEST INSTABILITY WILL SLOWLY
SHIFT EASTWARD, SO AREAS ALONG AND EAST OF THE CASCADES WILL BE THE
AREAS THAT LIKELY SEE THE MOST COVERAGE OF STORMS. FIRE ZONES 615
AND 618 SHOULD BE IN THE CLEAR, WHILE ISOLATED STORMS MAY STILL FORM
INLAND OVER THE WEST SIDE. IT WILL BE A CLOSE CALL FOR FIRE ZONE
619.
THE RIDGE AXIS SHIFTS EAST MONDAY AS THE UPPER TROUGH AXIS MOVES
THROUGH AND THUNDERSTORM THREAT SHOULD BE MOSTLY CONFINED TO
PORTIONS OF FIRE ZONES 624 AND 625. SPILDE
&&
.PREV DISCUSSION... /ISSUED 0850 AM PDT FRI JUN 26 2015/
UPDATED MARINE DISCUSSION.
DISCUSSION...A HOT AND UNSTABLE AIR MASS WILL PERSIST OVER THE
REGION DURING THE NEXT WEEK. LOW PRESSURE OFFSHORE FROM CALIFORNIA
AND HIGH PRESSURE CENTERED IN THE GREAT BASIN ARE THE MAIN UPPER
LEVEL FEATURES AFFECTING OUR WEATHER IN THE SHORT TERM WITH THAT
STRONG RIDGING LIKELY TO PERSIST THROUGH THE WEEK.
TODAY AND SATURDAY WILL BE THE HOTTEST DAYS WITH RECORD HIGHS LIKELY
TO BE SET. BUT, THE FOLLOWING FIVE DAYS WILL NOT BE THAT MUCH
COOLER. THE FORECAST HAS BEEN CONSISTENT IN EXPECTING VALLEY HIGHS
DURING THE NEXT TWO DAYS OF 95 TO 110 DEGREES ON THE WEST SIDE OF
THE CASCADES THIS AFTERNOON AND 92 TO 102 ON THE EAST SIDE.
THE OTHER MAIN FOCUS OF THE FORECAST IS THE DEVELOPMENT OF
THUNDERSTORMS WITH THE POTENTIAL FOR LIGHTNING TO CAUSE NEW FIRES.
ATMOSPHERIC MOISTURE LEVELS WILL GRADUALLY INCREASE WITH
PRECIPITABLE WATER AMOUNTS THAT WERE AT 0.50 TO 0.75 INCHES
YESTERDAY TO RISE TO 0.75 TO 1.00 INCHES TODAY. THE LEAST AMOUNT
OF RAINFALL WITH THUNDERSTORMS WILL BE IN THOSE THAT DEVELOP SOUTH
AND EAST OF SOUTHWEST OREGON. AN EARLY AFTERNOON THUNDERSTORM
CANNOT BE COMPLETELY RULED OUT, BUT THERE IS GOOD MODEL AGREEMENT
BETWEEN THE NAM AND THE SREF AND RAP SHORT TERM MODELS THAT THE
FIRST THUNDERSTORMS WILL DEVELOP AROUND 3 PM OVER THE HIGHER
TERRAIN FROM WESTERN SISKIYOU COUNTY TO THE SISKIYOU MOUNTAINS AND
CASCADES EASTWARD. COVERAGE OF STORMS WILL INCREASE DURING THE
EVENING WITH A PRIMARY FOCUS FOR NORTHWARD MOVING THUNDERSTORMS
FROM THE FOOTHILLS OF THE CASCADES (IN EASTERN PORTIONS OF JACKSON
AND DOUGLAS COUNTIES) EASTWARD. THAT WILL NOT BE THE EXCLUSIVE
LOCATION OF THUNDERSTORMS, JUST THE LIKELY FOCUS. THESE STORMS
WILL BE MOVING AT 10 TO 15 KNOTS. EMBEDDED SHORTWAVES IN THE
SOUTHERLY FLOW ALOFT ARE EXPECTED TO KEEP THUNDERSTORMS GOING
OVERNIGHT INTO SATURDAY MORNING WITH THE HIGHEST PROBABILITY ALONG
THE CASCADES. THERE IS UNCERTAINTY IN THE TRACK AND STRENGTH OF
SHORTWAVES AS THE GFS HAS A FOCUS DURING THE EVENING HOURS BEFORE
LIFTING THE MAJORITY OF ACTIVITY INTO NORTHERN OREGON WHILE THE
NAM SOLUTION WOULD ACTUALLY INCREASE THE NUMBER OF THUNDERSTORMS
IN OUR AREA DURING THE OVERNIGHT HOURS WHILE SPREADING THEM IN A
SOUTHEAST RATHER THAN SOUTH FLOW ALOFT TO THE COAST AND COASTAL
WATERS.
THUNDERSTORMS ON SATURDAY WILL PRODUCE MORE RAINFALL BUT THEY WILL
ALSO BE FASTER MOVING AT 15 TO 25 KNOTS. THUNDERSTORM COVERAGE IS
EXPECTED TO BE AT ITS PEAK DURING SATURDAY AFTERNOON AND EVENING.
THE PERSISTENT PATTERN WILL ONCE AGAIN PRODUCE NOCTURNAL
THUNDERSTORMS SATURDAY NIGHT INTO SUNDAY MORNING.
THERE IS UNCERTAINTY IN THE TIMING AND TRACK OF THE OFFSHORE LOW.
THE NAM IS FASTER THAN THE GFS BUT BOTH HAVE IT MOVING NORTH TO
THE SOUTHERN OREGON COAST ON SUNDAY. THIS WILL BRING IN SLIGHTLY
COOLER AIR AND EVENTUALLY KICK THE CONVECTIVE ACTIVITY TO THE
EAST WITH WEST SIDE OF THE CASCADES FOCUS OF THUNDERSTORMS ON
SUNDAY MORNING SHIFTING TO THE EAST SIDE FOR SUNDAY EVENING INTO
MONDAY. THUNDERSTORMS ON SUNDAY WILL HAVE A HIGHER PROBABILITY OF
PRODUCING SEVERE WIND GUSTS. THE TROUGH WITH A MUCH DRIER AIR
MASS WILL BE IN PLACE OVER THE PACIFIC NORTHWEST ON MONDAY. THUS,
A SLIGHT CHANCE OF THUNDERSTORMS WILL BE NEARLY LIMITED TO ONLY
LAKE AND MODOC COUNTIES. MONDAY NIGHT SHOULD TRANSPIRE WITHOUT
THUNDERSTORMS.
RIDGING FROM THE GREAT BASIN IS EXPECTED TO REBUILD INTO OUR AREA
TUESDAY FOR THE START OF ANOTHER WARMING TREND INTO THURSDAY.
THIS WILL ALSO SEND HIGHER AMOUNTS OF MOISTURE INTO THE EAST SIDE
ON TUESDAY THAT WILL EXPAND FARTHER WEST...TO THE WEST SIDE ON
WEDNESDAY FOR ANOTHER EPISODE OF A SLIGHT CHANCE OF AFTERNOON AND
EVENING THUNDERSTORMS. THE PROBABILITY WILL BE THE LOWEST FOR THE
COAST AND DOUGLAS COUNTY.
FORECAST UNCERTAINTY INCREASES BEYOND WEDNESDAY AS THE ECMWF MODEL
INDICATES A STRONG TROUGH MOVING INTO THE PACIFIC NORTHWEST WILL
FINALLY CHANGE THE PATTERN AND BRING SOME COOLING FOR THE END OF
THE WEEK, BUT THE GFS IS PERSISTENT AND LEAVES THE HOT GREAT
BASIN RIDGE IN COMMAND. FOR NOW, WE WILL LEAN TOWARD PERSISTENCE.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR... RED FLAG WARNING FROM 5 PM THIS AFTERNOON TO 11 PM PDT SUNDAY
FOR ORZ615>625.
HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 5 AM PDT SUNDAY FOR
ORZ023.
HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 5 AM PDT SUNDAY FOR
ORZ024-026.
CA...RED FLAG WARNING FROM 5 PM THIS AFTERNOON TO 11 PM PDT SUNDAY
FOR CAZ280-281-284-285.
HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 5 AM PDT SUNDAY FOR
CAZ080-081.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 PM PDT THIS EVENING FOR
PZZ350-356-370-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 AM PDT SATURDAY
FOR PZZ350-356.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 AM PDT SATURDAY
FOR PZZ370-376.
GALE WARNING UNTIL 11 PM PDT THIS EVENING FOR PZZ376.
HAZARDOUS SEAS WARNING UNTIL 11 PM PDT THIS EVENING FOR PZZ376.
$$
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
142 PM EDT FRI JUN 26 2015
.SYNOPSIS...
HIGH PRESSURE WILL WEAKEN ACROSS THE SOUTHEAST TODAY AS A COLD FRONT
APPROACHES. THE COLD FRONT MOVES THROUGH SATURDAY...MOVING EAST OF
THE REGION BY SUNDAY. A WEAK FRONT WILL APPROACH BY MID WEEK AND
LINGER NEAR THE REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
130 PM EDT UPDATE...CONVECTIVE ACTIVITY HAS HELD OFF THUS FAR THIS
AFTERNOON DUE TO SOME INHIBITION TO VERTICAL MOTION...ESPECIAL IN
AREAS IN THE MOUNTAINS TO THE NORTH. MOST MODELS HAVE CONVECTIVE
ACTIVITY LATER THIS AFTERNOON...THOUGH WITH DISAGREEMENTS IN
LOCATION AND TIMING. CURRENTLY EXPECT CUMULUS FIELD OVER WESTERN
GEORGIA TO CONTINUE TO DEVELOP INTO PULSE-TYPE THUNDERSTORMS LATER
THIS AFTERNOON. POTENTIALLY MORE SEVERE STORMS COULD DEVELOP OVER
THE BLUE RIDGE AS WELL...IF NEGATIVE ENERGY IN THE SOUNDINGS CAN BE
OVERCOME...CURRENT SATELLITE SHOWS SOME CU FINALLY BEGINNING TO
DEVELOP OVER THE MOUNTAINS AS WELL.
1030 AM EDT UPDATE...AREA IS CLEAR OF RADAR ACTIVITY AT THE
MOMENT...WITH AT LEAST SOME ACTIVITY EXPECTED LATER THIS AFTERNOON.
LATEST HRRR HAS SOME CONVECTION AFTER 19Z. SHEAR IS BETTER TO THE
NORTH IN THE BLUE RIDGE MOUNTAINS...WITH A CONSEQUENT INCREASE IN
THE POSSIBILITY FOR SEVERE WEATHER. TWEAKED
TEMPERATURES...SKY...AND POP TO ACCOUNT FOR LATEST OBSERVATIONS AND
HRRR EXPECTATIONS.
AS OF 6 AM...AIDED BY ENCROACHING OUTFLOW BOUNDARIES...A FEW SHOWERS
SHOULD PERCOLATE ALONG THE TENN BORDER COUNTIES BEFORE ASHING OUT
LATER THIS MORNING. OTHERWISE...VARYING DEGREES OF HIGH LVL DEBRIS
CLOUDS WILL GIVE WAY TO DEVELOPING CU.
THERE REMAINS THE POSSIBILITY OF DEEP CONVECTIVE REMNANTS FROM KY
MCS ACTIVITY REACHING THE NC MTNS BY DAYBREAK BEFORE ASHING OUT
COMPLETELY BY MID-MORNING. WILL CONTINUE TO MONITOR CONVECTION
ALLOWING MODELS AND UPSTREAM TRENDS. EXPECTING AN UPTICK IN FORCING
AND FLOW AS THE AFTERNOON AND EVENING WEARS ON AS S/WV ENERGY
ENCROACHES THE SE CONUS AND UPPER HEIGHTS STEADILY FALL. GIVEN
THIS...TSTM CVRG MAY WIND UP BECOMING NUMEROUS AND POSSIBLY SVR
THIS AFTERNOON GIVEN FORECAST SNDGS DEPICTING MODERATE
INSTABILITY...DECENTLY STEEP LAPSE RATES AND FAVORABLE DELTA THETA-E
VALUES. WILL FORECAST ONE MORE HOT DAY TODAY...CLOSE TO PERSISTENCE
AND FEATURING WIDESPREAD MIDDLE AND UPPER 90S ACRS THE PIEDMONT.
IMPULSES WITHIN THE QUICKENING SW FLOW MAY BE ABLE TO SUSTAIN SOME
DEGREE OF TSTM ACTIVITY WELL PAST SUNSET...WILL WILL KEEP AT LEAST A
TOKEN CHANCE POP INTO THE OVERNIGHT HOURS.
&&
.SHORT TERM /SATURDAY/...
AT 230 AM EDT FRIDAY...ON SATURDAY MORNING AN UPPER TROUGH WILL BE
OVER THE EASTER USA...WHILE A RIDGE WILL BE OVER THE WEST. THIS
PATTERN AMPLIFIES INTO SUNDAY...WHILE A CLOSED UPPER LOW CROSSES THE
LOWER GREAT LAKES. A WEAKER OPEN UPPER LOW CROSSES THE UPPER GREAT
LAKES ON SUNDAY NIGHT.
AT THE SURFACE...A ROBUST COLD WILL APPROACH FORM THE WEST ON ON
SATURDAY...CROSSING THE AREA IN THE EARLY EVENING. WHILE CAPE MAY BE
SOMEWHAT MODEST...SHEAR WILL BE PRESENT...AND ORGANIZED CONVECTION
CANNOT BE RULED OUT. COOLER AND DRIER AIR WILL MOVE IN BEHIND THE
FRONT FROM SATURDAY NIGHT THROUGH SUNDAY NIGHT. TEMPERATURES WILL
RUN BELOW NORMAL.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
AT 230 AM EDT FRIDAY...ON MONDAY AN ANOMALOUS HIGH AMPLITUDE UPPER
ROUGH WILL EXTENDING ROM HUDSON BAY TO THE GULF OF MEXICO...WHILE AN
UPPER RIDGE WILL BE OVER THE WESTERN USA AND WESTER CANADA. THIS
PATTER PERSISTS INTO TUESDAY...THEN DEAMPLIFIES ON WEDNESDAY. ON
THURSDAY THE UPPER TROUGH REAMPLIFIES SOMEWHAT...WHILE THE RIDGE TO
THE WEST REMAINS RATHER FLAT.
AT THE SURFACE...A SURFACE RIDGE WILL BE OVER THE SOUTHERN
APPALACHIANS ON MONDAY...IN THE WAKE OF A DEPARTING COLD FRONT. THE
TRAILING PORTION OF THE FRONT LIFTS NORTH ACROSS OUR AREA AS A WARM
FRONT BY EARLY TUESDAY. ANOTHER COLD FRONT DROPS SOUTHEAST ACROSS
OUR AREA ON WEDNESDAY...STALLING NEAR THE NC AND SC BORDER BY
THURSDAY. A WEAK CAPPING INVERSION ALOFT MAY KEEP OUR AREA SOMEWHAT
STABLE ON MONDAY...BUT WITH FRONTS MOVING TROUGH THE AREA AND
INSTABILITY INCREASING...THE REST OF THE WEEK SHOULD BE INCREASINGLY
MORE ACTIVE. TEMPERATURES WILL RUN NEAR NORMAL.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AT KCLT AND ELSEWHERE...SHOWERS AND STORMS HAVE HELD OFF THUS FAR
THIS AFTERNOON...HOWEVER SOME CUMULUS IS DEVELOPING AS SEEN ON THE
VISIBLE SATELLITE...WHICH MAY SIGNAL THE APPROACH OF CONVECTIVE
ACTIVITY LATER THIS AFTERNOON. LOCATION AND TIMING OF THUNDER IS
SOMEWHAT UNCERTAIN DUE TO POORLY DEFINED SURFACE BOUNDARIES AND
FORCING MECHANISMS. CAMS HAVE BEEN INCONSISTENT AS WELL. CURRENTLY
EXPECT SOME PULSE STORM ACTIVITY IN AREAS ON THE PIEDMONT HELPED BY
A WEAK SHORTWAVE IMPULSE TRAVERSING THE AREA...POTENTIALLY MORE
SEVERE ACTIVITY MAY INITIATE IN THE HIGHER TERRAIN IF SOME
CONVECTIVE INHIBITION CAN BE OVERCOME. A BREAK IN SHOWERS IS
EXPECTED AFTER 6Z BEFORE THE APPROACH OF A COLD FRONT SATURDAY
AFTERNOON.
OUTLOOK...A COLD FRONT WILL APPROACH FROM THE NW AND PASS THRU
ON SATURDAY. MORNING RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE
POSSIBLE...PARTICULARLY WHERE HEAVY RAIN FALLS LATER TODAY...AND IN
THE MOUNTAIN RIVER VALLEYS. BEHIND THE COLD FRONT...A MUCH DRIER AND
COOLER AIRMASS WILL OVERSPREAD THE REGION FOR EARLY NEXT WEEK...WITH
A SECOND COLD FRONT POSSIBLY ARRIVING BY MID-WEEK.
CONFIDENCE TABLE...
17-23Z 23-05Z 05-11Z 11-12Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 91%
KAVL HIGH 100% HIGH 100% HIGH 100% LOW 58%
KHKY HIGH 100% HIGH 100% HIGH 100% LOW 58%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 91%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JAT
NEAR TERM...CSH/WJM
SHORT TERM...JAT
LONG TERM...JAT
AVIATION...WJM
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
130 PM EDT FRI JUN 26 2015
.SYNOPSIS...
HIGH PRESSURE WILL WEAKEN ACROSS THE SOUTHEAST TODAY AS A COLD FRONT
APPROACHES. THE COLD FRONT MOVES THROUGH SATURDAY...MOVING EAST OF
THE REGION BY SUNDAY. A WEAK FRONT WILL APPROACH BY MID WEEK AND
LINGER NEAR THE REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
1030 AM EDT UPDATE...AREA IS CLEAR OF RADAR ACTIVITY AT THE
MOMENT...WITH AT LEAST SOME ACTIVITY EXPECTED LATER THIS AFTERNOON.
LATEST HRRR HAS SOME CONVECTION AFTER 19Z. SHEAR IS BETTER TO THE
NORTH IN THE BLUE RIDGE MOUNTAINS...WITH A CONSEQUENT INCREASE IN
THE POSSIBILITY FOR SEVERE WEATHER. TWEAKED
TEMPERATURES...SKY...AND POP TO ACCOUNT FOR LATEST OBSERVATIONS AND
HRRR EXPECTATIONS.
AS OF 6 AM...AIDED BY ENCROACHING OUTFLOW BOUNDARIES...A FEW SHOWERS
SHOULD PERCOLATE ALONG THE TENN BORDER COUNTIES BEFORE ASHING OUT
LATER THIS MORNING. OTHERWISE...VARYING DEGREES OF HIGH LVL DEBRIS
CLOUDS WILL GIVE WAY TO DEVELOPING CU.
THERE REMAINS THE POSSIBILITY OF DEEP CONVECTIVE REMNANTS FROM KY
MCS ACTIVITY REACHING THE NC MTNS BY DAYBREAK BEFORE ASHING OUT
COMPLETELY BY MID-MORNING. WILL CONTINUE TO MONITOR CONVECTION
ALLOWING MODELS AND UPSTREAM TRENDS. EXPECTING AN UPTICK IN FORCING
AND FLOW AS THE AFTERNOON AND EVENING WEARS ON AS S/WV ENERGY
ENCROACHES THE SE CONUS AND UPPER HEIGHTS STEADILY FALL. GIVEN
THIS...TSTM CVRG MAY WIND UP BECOMING NUMEROUS AND POSSIBLY SVR
THIS AFTERNOON GIVEN FORECAST SNDGS DEPICTING MODERATE
INSTABILITY...DECENTLY STEEP LAPSE RATES AND FAVORABLE DELTA THETA-E
VALUES. WILL FORECAST ONE MORE HOT DAY TODAY...CLOSE TO PERSISTENCE
AND FEATURING WIDESPREAD MIDDLE AND UPPER 90S ACRS THE PIEDMONT.
IMPULSES WITHIN THE QUICKENING SW FLOW MAY BE ABLE TO SUSTAIN SOME
DEGREE OF TSTM ACTIVITY WELL PAST SUNSET...WILL WILL KEEP AT LEAST A
TOKEN CHANCE POP INTO THE OVERNIGHT HOURS.
&&
.SHORT TERM /SATURDAY/...
AT 230 AM EDT FRIDAY...ON SATURDAY MORNING AN UPPER TROUGH WILL BE
OVER THE EASTER USA...WHILE A RIDGE WILL BE OVER THE WEST. THIS
PATTERN AMPLIFIES INTO SUNDAY...WHILE A CLOSED UPPER LOW CROSSES THE
LOWER GREAT LAKES. A WEAKER OPEN UPPER LOW CROSSES THE UPPER GREAT
LAKES ON SUNDAY NIGHT.
AT THE SURFACE...A ROBUST COLD WILL APPROACH FORM THE WEST ON ON
SATURDAY...CROSSING THE AREA IN THE EARLY EVENING. WHILE CAPE MAY BE
SOMEWHAT MODEST...SHEAR WILL BE PRESENT...AND ORGANIZED CONVECTION
CANNOT BE RULED OUT. COOLER AND DRIER AIR WILL MOVE IN BEHIND THE
FRONT FROM SATURDAY NIGHT THROUGH SUNDAY NIGHT. TEMPERATURES WILL
RUN BELOW NORMAL.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
AT 230 AM EDT FRIDAY...ON MONDAY AN ANOMALOUS HIGH AMPLITUDE UPPER
ROUGH WILL EXTENDING ROM HUDSON BAY TO THE GULF OF MEXICO...WHILE AN
UPPER RIDGE WILL BE OVER THE WESTERN USA AND WESTER CANADA. THIS
PATTER PERSISTS INTO TUESDAY...THEN DEAMPLIFIES ON WEDNESDAY. ON
THURSDAY THE UPPER TROUGH REAMPLIFIES SOMEWHAT...WHILE THE RIDGE TO
THE WEST REMAINS RATHER FLAT.
AT THE SURFACE...A SURFACE RIDGE WILL BE OVER THE SOUTHERN
APPALACHIANS ON MONDAY...IN THE WAKE OF A DEPARTING COLD FRONT. THE
TRAILING PORTION OF THE FRONT LIFTS NORTH ACROSS OUR AREA AS A WARM
FRONT BY EARLY TUESDAY. ANOTHER COLD FRONT DROPS SOUTHEAST ACROSS
OUR AREA ON WEDNESDAY...STALLING NEAR THE NC AND SC BORDER BY
THURSDAY. A WEAK CAPPING INVERSION ALOFT MAY KEEP OUR AREA SOMEWHAT
STABLE ON MONDAY...BUT WITH FRONTS MOVING TROUGH THE AREA AND
INSTABILITY INCREASING...THE REST OF THE WEEK SHOULD BE INCREASINGLY
MORE ACTIVE. TEMPERATURES WILL RUN NEAR NORMAL.
&&
.AVIATION /17Z FRIDAY THROUGH TUESDAY/...
AT KCLT AND ELSEWHERE...SHOWERS AND STORMS HAVE HELD OFF THUS FAR
THIS AFTERNOON...HOWEVER SOME CUMULUS IS DEVELOPING AS SEEN ON THE
VISIBLE SATELLITE...WHICH MAY SIGNAL THE APPROACH OF CONVECTIVE
ACTIVITY LATER THIS AFTERNOON. LOCATION AND TIMING OF THUNDER IS
SOMEWHAT UNCERTAIN DUE TO POORLY DEFINED SURFACE BOUNDARIES AND
FORCING MECHANISMS. CAMS HAVE BEEN INCONSISTENT AS WELL. CURRENTLY
EXPECT SOME PULSE STORM ACTIVITY IN AREAS ON THE PIEDMONT HELPED BY
A WEAK SHORTWAVE IMPULSE TRAVERSING THE AREA...POTENTIALLY MORE
SEVERE ACTIVITY MAY INITIATE IN THE HIGHER TERRAIN IF SOME
CONVECTIVE INHIBITION CAN BE OVERCOME. A BREAK IN SHOWERS IS
EXPECTED AFTER 6Z BEFORE THE APPROACH OF A COLD FRONT SATURDAY
AFTERNOON.
OUTLOOK...A COLD FRONT WILL APPROACH FROM THE NW AND PASS THRU
ON SATURDAY. MORNING RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE
POSSIBLE...PARTICULARLY WHERE HEAVY RAIN FALLS LATER TODAY...AND IN
THE MOUNTAIN RIVER VALLEYS. BEHIND THE COLD FRONT...A MUCH DRIER AND
COOLER AIRMASS WILL OVERSPREAD THE REGION FOR EARLY NEXT WEEK...WITH
A SECOND COLD FRONT POSSIBLY ARRIVING BY MID-WEEK.
CONFIDENCE TABLE...
17-23Z 23-05Z 05-11Z 11-12Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 91%
KAVL HIGH 100% HIGH 100% HIGH 100% LOW 58%
KHKY HIGH 100% HIGH 100% HIGH 100% LOW 58%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 91%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JAT
NEAR TERM...CSH/WJM
SHORT TERM...JAT
LONG TERM...JAT
AVIATION...WJM
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
235 PM EDT FRI JUN 26 2015
.SHORT TERM /THIS AFTERNOON THROUGH SATURDAY/...
THE ATMOSPHERE HAS VERY QUICKLY DESTABILIZED EARLY THIS
AFTERNOON...UNDER A SUNNY SKY AND A MOIST ENVIRONMENT. TEMPERATURES
HAVE SOARED INTO THE UPPER 80S TO LOWER 90S OVER MUCH OF THE AREA
AS OF 2 PM EDT...WITH DEWPOINTS STILL IN THE LOW 70S IN MANY
PLACES. THE STAGE IS SET FOR SCATTERED DIURNAL THUNDERSTORM
DEVELOPMENT THIS AFTERNOON...WITH STORMS HAVING THE POTENTIAL TO GO
STRONG/SEVERE VERY QUICKLY. CAPE VALUES /ALREADY HIGH/...ARE
PROGGED TO CLIMB AS HIGH AS 4000+ J/KG BY THE AFTERNOON. THIS WILL
ALSO FOR SOME STRONG/ROBUST UPDRAFTS CAPABLE OF PRODUCING LOCALIZED
DOWNBURSTS IN THIS FAVORABLE ENVIRONMENT. ADDITIONALLY...LIGHTNING...
HEAVY RAINFALL AND MARGINALLY SEVERE HAIL ARE POSSIBLE.
THIS INITIAL DIURNAL ACTIVITY SHOULD WANE BY EARLY EVENING. THE THEN
MORE CHALLENGING ASPECT OF THE FORECAST WILL BE WHAT EXACTLY WILL
OCCUR THIS EVENING/OVERNIGHT. THE LATEST RUNS OF THE HRRR SHOW A
MUCH MORE PROGRESSIVE MCS/CONVECTIVE SYSTEM DEVELOPING OVER WESTERN
KY/TN AND MOVING INTO THE NW PLATEAU/CUMBERLAND MTNS OF SW VA AROUND
03Z. THE NAM/GFS SOLUTIONS ARE SLOWER...WITH THE CONVECTIVE LINE /IN
A WEAKER STATE/...MAKING IT IN AROUND/AFTER 06Z. WHILE INSTABILITY IS
MUCH WEAKER /COMPARED TO THIS AFTERNOON/ AFTER SUNSET...WIND SHEAR
INCREASES QUITE A BIT AS THE 850 MB LLJ RAMPS UP AND MOVES NORTHEAST
OF MIDDLE TN/EASTERN KY. THOUGH SLIGHTLY DISPLACED...THIS FEATURE
MAY HELP TO KEEP THE LINE GOING INTO OUR AREA LATE THIS EVENING AND
INTO PARTS OF THE OVERNIGHT HOURS. THUS...THINK THAT THERE IS AT
SOME RISK FOR ADDITIONAL SEVERE STORMS ALONG THE LINE LATER TONIGHT
DESPITE SOME UNCERTAINTY WITH THE EXACT TIMING/DETAILS.
THIS ACTIVITY WILL CONTINUE INTO THE MORNING ON SATURDAY...THOUGH IN
A MUCH WEAKENED STATE. GOOD CHANCES FOR MUCH NEEDED RAINFALL WILL
EXIST WITH THIS SHOWERY ACTIVITY AHEAD OF THE FRONT. ATTENTION WILL
QUICKLY TURN TO THE AFTERNOON AS THE ACTUAL COLD FRONT FINALLY MAKES
IT INTO THE REGION. SOUNDING PROFILES INDICATE THAT SOME HEATING
WILL OCCUR PRIOR TO THE FRONTAL PASSAGE. THIS WILL ALLOW FOR AT
LEAST A MARGINALLY UNSTABLE ENVIRONMENT TO DEVELOP OVER THE AREA BY
THE MID AFTERNOON. COMBINED WITH BETTER 40-50 KT BULK SHEAR AND
SOME COOLER TEMPS ALOFT/LOWER WET-BULB ZERO HGTS...A MARGINAL RISK
FOR SEVERE STORMS WILL EXIST IN THE AFTERNOON...MAINLY IN THE
18-00Z TIMEFRAME. SOUNDINGS ALSO SHOW SOME DRIER AIR NEAR THE
SURFACE...WHICH WOULD SUGGEST A LOCALIZED DOWNBURST THREAT...ALONG
WITH SMALL HAIL. COOLER TEMPS WILL BE IN STORE...WITH HIGHS IN THE
UPPER 70S TO LOWER 80S EXPECTED.
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
A COLD FRONT WILL BE EXITING THE AREA SATURDAY EVENING AND A FEW
SHOWERS MAY LINGER ACROSS THE REGION UNTIL AROUND MIDNIGHT.
HOWEVER...BEHIND THE FRONT...DRY AND MUCH COOLER AIR WILL PUSH IN.
SUNDAY SHOULD BE DRY AND WILL ONLY SEE HIGHS REACH INTO THE LOWER
TO MID 80S ACROSS MUCH OF THE VALLEY. THE COOLER AIR MASS WILL
PERSIST THROUGHOUT THE EXTENDED BUT THE DRY CONDITIONS WILL BE
SHORT LIVED AS WE QUICKLY TRANSITION INTO AN UNSETTLE WEATHER
PATTERN. THROUGHOUT THE WEEK...A SERIES OF WEATHER SYSTEMS WILL
MOVE THROUGH. TIMING OF EACH SYSTEM OR DISTURBANCE IS IN QUESTION
BUT SHOULD SEE A CHANCE OF CONVECTION PRETTY MUCH EACH PERIOD. THE
PERIODS WITH THE BEST CHANCE OF SCATTERED THUNDERSTORM DEVELOP WILL
BE MONDAY NIGHT INTO TUESDAY AND AGAIN AROUND THE THURSDAY TIME
FRAME.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 73 83 63 85 / 70 80 20 0
KNOXVILLE MCGHEE TYSON AIRPORT, TN 71 81 60 82 / 80 80 20 0
OAK RIDGE, TN 71 80 60 82 / 80 80 20 0
TRI CITIES AIRPORT, TN 68 78 58 79 / 80 80 30 10
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
AMP/MJB
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
215 PM CDT FRI JUN 26 2015
.SHORT TERM...(TONIGHT THROUGH SUNDAY)
ISSUED AT 215 PM CDT FRI JUN 26 2015
CONVECTION FIRING IN A BROAD REGION OF UNSTABLE AIR...JUST NEEDING A
FOCUS TO GET IT GOING. LATEST RADAR IMAGERY PLACES ONE CLUSTER
DIVING SOUTH ACROSS CENTRAL MN IS TIED TO A BIT OF UPPER LEVEL
ENERGY. OVER IA INTO NORTHERN ILL IS CO-LOCATED WITH THE BASE OF THE
UPPER LEVEL TROUGH. ELSEWHERE...ENHANCED CU AND SOME ISOLATED
SHOWERS WERE THE RULE. HEADING INTO THE EVENING...EXPECT BOTH AREAS
OF PCPN TO CONTINUE - DYING OUT WITH THE LOSS OF THE DAYTIME
HEATING. BUT...THE RAP AND NAM12 SUGGEST A SOUTHWEST-NORTHEAST
RUNNING BOUNDARY ACROSS THE FORECAST AREA...WHICH COULD SERVE AS A
TRIGGER FOR A SCATTERED LINE OF SHOWERS/STORMS LATE AFTERNOON/EARLY
EVENING. WILL MONITOR AND INCREASE POPS IF THIS BECOMES LIKELY.
UPPER LEVEL SHORTWAVE TROUGH SLATED TO MOVE ACROSS THE AMPLIFIED
RIDGE OVER THE WEST...SPINNING ACROSS THE UPPER MISSISSIPPI RIVER
VALLEY ON SUNDAY. DECENT QG CONVERGENCE WITH THIS FEATURE...ALONG
WITH LOW LEVEL WARMING - ALTHOUGH MOSTLY CENTERED OVER IA. 300 MB
JET STREAK LOOKS TO ENHANCE THE LIFT. PLENTY OF DYNAMICS AND ENOUGH
SATURATION FOR AN AREA OF SHOWERS AND THUNDERSTORMS...AND ALL THE
MODELS HAVE SAID AS MUCH OVER THE PAST FEW DAYS.
QUESTIONS ARISE WITH THE TIMING OF THE SHORTWAVE/AREAS OF RAIN AND
HOW MUCH INSTABILITY/SHEAR WILL BE PRESENT. 12Z GFS/NAM RUNS BRING
THE SHORTWAVE IN BY 12Z SUN...WITH PCPN LIKELY FOR AT LEAST THE
WESTERN 1/2 OF THE FORECAST AREA BY THAT TIME. THE PCPN AND TROUGH
AXIS THEN SWINGS INTO WESTERN WI FOR SUN AFTERNOON. NOT A LOT OF
SHEAR THROUGH THE DAY...MOST OF WHICH LIES IN THE 0-3KM LAYER -
ROUGHLY 20-30 KTS. AS ONE WOULD EXPECT...NOT MUCH INSTABILITY AT 12Z
SUN MORNING...BUT THE GFS/NAM DEVELOP A RIBBON OF 1500-2000 J/KG
SBCAPE ACROSS THE WESTERN 2/3RDS OF THE FORECAST AREA IN THE
AFTERNOON. HOWEVER...THIS IS POST THE PCPN SHIELD AND MUCH OF THE
DYNAMICS. NOT SURE IT WILL/COULD BE UTILIZED BY THE EXPECTED ONGOING
CONVECTION...OR FOR ANY REDEVELOPMENT IN THE WEST. AS A
RESULT...BELIEVE THE POTENTIAL FOR ORGANIZED SEVERE WEATHER IS
LOW...ALTHOUGH A FEW STRONGER STORMS COULD BE POSSIBLE. ALL IN
ALL...SUNDAY LOOKS LIKE A WET DAY...WEST OF THE MISSISSIPPI RIVER IN
THE MORNING...EAST IN THE AFTERNOON.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 215 PM CDT FRI JUN 26 2015
AFTER SUNDAY...THE GFS/ECMWF HOLD ONTO THE WESTERN RIDGE-EASTERN
TROUGH CONFIGURATION FOR MUCH OF THE NEW WEEK...KEEPING THE LOCAL
AREA UNDER NORTHWEST FLOW. VARIOUS PERTURBATIONS IN THE UPPER LEVEL
LEVEL FLOW WOULD SPIN ACROSS THE UPPER MISSISSIPPI RIVER
VALLEY...RESULTING IN PERIODIC RAIN CHANCES. MODEL DIFFERENCES IN
PLACEMENT AND TIMING OF THESE BITS OF ENERGY - AS EXPECTED - BUT
NONE OF THE SOLUTIONS ARE SUGGESTIVE OF WIDESPREAD...ALL-DAY KIND OF
RAIN EVENTS. INSTABILITY AND WIND SHEAR DON/T FAVOR ORGANIZED SEVERE
WEATHER AT THIS TIME EITHER. WILL CONTINUE THE BLANKET OF SMALL RAIN
CHANCES THROUGH THE PERIOD...REVISING AS THE DETAILS BECOMING
CLEARER.
WITH THE RELATIVELY COOLER NORTHWEST TRAJECTORY COUPLED WITH
CLOUDS/RAIN POTENTIAL...TEMPERATURES SHOULD HOLD NEAR OR BELOW THE
SEASONABLE NORMALS. IN ADDITION...NO TO LIMITED TAP INTO GULF
MOISTURE DURING THE WEEK SHOULD KEEP HUMIDITIES IN CHECK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1254 PM CDT FRI JUN 26 2015
ISOLATED SHOWERS ARE DEVELOPING ALONG A WEAK AREA OF CONVERGENCE
ACROSS SOUTHEAST MINNESOTA. DUE TO THIS...INCLUDED SHOWERS IN THE
TEMPO GROUP AT KRST THROUGH 26.20Z. OTHERWISE...THERE WILL BE A
SCATTERED TO BROKEN 3-5K DECK OF CLOUDS THROUGH 27.05Z AND THEN
SKIES WILL CLEAR. WINDS WILL BE INITIALLY BE NORTHEAST AND THEN
SHIFT TO NORTH AFTER 27.05Z. WIND SPEEDS WILL BE LESS THAN 10 KNOTS.
WITH LIGHT WINDS TONIGHT AND SCATTERED SHOWERS THROUGH THIS
EVENING...WILL HAVE TO WATCH FOR THE POTENTIAL OF FOG...BUT WITH
UNCERTAINTY ON WHERE THESE SHOWERS WILL OCCUR...DID NOT INCLUDE IT
IN THE TAFS AT THIS TIME.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION.....BOYNE