Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/12/14
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
244 AM MDT THU JUL 10 2014
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 223 AM MDT THU JUL 10 2014
THE UPPER LEVEL RIDGE OVER THE SRN ROCKIES WILL EXPAND NORTHWARD
THRU THIS AFTN INTO NRN CO WITH THE MID FLOW BECOMING MORE WSW.
PRECIPITABLE WATER VALUES EAST OF THE MTNS HAVE DECREASED AROUND 25%
FROM YESTERDAY WHILE OVER WRN CO THEY ARE SLIGHTLY HIGHER.
MEANWHILE WITH THE UPPER LEVEL RIDGE BUILDING NORTHWARD MID LVL
TEMPS ARE FCST TO RISE A FEW DEGREES AS WELL.
IN THE MTNS WILL CONTINUE TO SEE A CHC OF SHOWERS AND TSTMS THIS
AFTN. OVER NERN CO AM SOMEWHAT CONCERNED WITH THE MID LVL WARMING
THIS AFTN WHICH COULD INHIBIT CONVECTION IN MOST AREAS EXCEPT
POSSIBLY NEAR THE WY BORDER. THUS WILL KEEP POPS IN THE 10 TO 20
PERCENT RANGE FOR THIS AFTN INTO THE EVENING HOURS EXCEPT NR THE WY
BORDER WHERE THERE WILL BE SLIGHTLY HIGHER POPS. WITH LESS
INSTABILITY THIS AFTN AND WK SHEAR PROFILE THREAT OF SVR WX LOOKS
LOW.
AS FOR HIGHS 850-700 MB TEMPS RISE ANOTHER COUPLE OF DEGREES SO AFTN
HIGHS WILL BE MOSTLY IN THE MID TO UPPER 90S ACROSS NERN CO.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 223 AM MDT THU JUL 10 2014
MODELS SHOW THE UPPER RIDGE CENTER JUST SOUTHEAST OF COLORADO
FRIDAY THROUGH FRIDAY EVENING...THEN THE CENTER MIGRATES WESTWARD
SATURDAY MORNING. IT IS CENTERED OVER THE EASTERN GREAT BASIN BY
12Z SUNDAY MORNING. THE FLOW ALOFT IS WEAK WEST-SOUTHWESTERLY
FRIDAY AND FRIDAY NIGHT...THEN ZONAL SATURDAY AND SATURDAY
EVENING...THEN WEST-NORTHWESTERLY BY 12Z SUNDAY MORNING. WEAK
UPWARD QG VERTICAL VELOCITY IS PROGGED FOR THE CWA FRIDAY THROUGH
SATURDAY. THE BOUNDARY LAYER FLOW LOOKS TO BE PREDOMINATELY
UPSLOPE FRIDAY...FRIDAY NIGHT AND SATURDAY. THERE ARE A COUPLE OF
COLD FRONTS PROGGED INTO THE CWA. THE MORE SIGNIFICANT ONE IS FOR
FRIDAY. FOR MOISTURE...THERE IS PLENTY PROGGED FRIDAY THROUGH
SATURDAY NIGHT. PRECIPITABLE WATER VALUES ON ALL THE MODELS FOR
ALL THE PLAINS AND LOWER FOOTHILLS ARE PROGGED OVER 1.00 INCH
FRIDAY THROUGH SATURDAY NIGHT. BOUNDARY LAYER DEW POINTS ARE IN
THE 50 TO 65 F RANGE FOR THE PLAINS AND FOOTHILLS ALL FOUR
PERIODS. PRETTY DECENT CAPE IS PROGGED OVER THE CWA...ESPECIALLY
DURING THE AFTERNOONS AND EVENINGS. SOME AREAS OF THE PLAINS HAVE
VALUES OVER 2000 J/KG. THE QPF FIELDS HAVE WIDESPREAD MEASURABLE
PRECIPITATION OVER THE CWA LATE DAY FRIDAY AND LATE DAY SATURDAY.
THE GFS HAS THE HIGHEST AMOUNTS BUT ALL THE MODELS WEIGHT IN WITH
SOMETHING. WILL GO WITH 30-50% POPS FRIDAY LATE AND SATURDAY LATE.
WILL EVEN KEEP SOME GOING...ESPECIALLY OVER THE EAST FOR THE
06-12Z PERIODS. FOR TEMPERATURES...FRIDAY`S HIGHS ARE 3-6 C
COOLER THAN TODAY`S WITH THE COOLER AIRMASS AND MORE MOISTURE.
SATURDAY`S HIGHS ARE 0-1 C COOLER THAN FRIDAY`S. FOR THE LATER
DAYS...SUNDAY THROUGH WEDNESDAY...MODELS HAVE THE UPPER RIDGE
CENTER STAYING OVER THE GREAT BASIN SUNDAY THROUGH TUESDAY
NIGHT...THEN IT MOVES FURTHER WEST THROUGH WEDNESDAY. AN UPPER
TROUGH/CLOSED LOW IS PROGGED OVER THE NORTHERN AND NORTHEASTERN
UNITED STATES SUNDAY THROUGH TUESDAY...WITH ITS TAIL END GETTING
INTO THE CWA PERHAPS. LATER TUESDAY INTO WEDNESDAY...A WEAK UPPER
TROUGH IS PROGGED TO MOVE INTO THE CWA. THERE WILL BE COOLER
TEMPERATURES AND MOISTURE FOR POPS.
&&
.AVIATION...(FOR THE TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 223 AM MDT THU JUL 10 2014
TSTM CHANCES LOOK RATHER LOW TODAY HOWEVER STILL CAN`T RULE OUT AN
ISOLATED HIGH BASED STORM IF OUTFLOW BOUNDARIES FM HIGHER TERRAIN
CONVECTION MOVE ACROSS LATE THIS AFTN SO WILL LEAVE VCTS IN TAF. AS
FAR AS WINDS WILL TREND TOWARDS THE HRRR AND HAVE AN ESE COMPONENT
DEVELOPING BY EARLY AFTN WITH SPEEDS IN THE 10-15 MPH RANGE. MAY
SEE A WIND SHIFT TO THE NW AROUND 00Z IF OUTFLOW BOUNDARIES MOVE
ACROSS AND THEN MORE SWLY BY 02Z WITH DRAINAGE WINDS OVERNIGHT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RPK
LONG TERM...RJK
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1109 PM MDT WED JUL 9 2014
.UPDATE...
ISSUED AT 903 PM MDT WED JUL 9 2014
QUICK UPDATE TO ACCOUNT FOR THE LATEST RADAR TRENDS. CURRENTLY A
BAND OF STRONG THUNDERSTORMS IS DROPPING SOUTH OUT OF CHEYENNE AND
KIT CARSON COUNTIES...AND WILL DROP SOUTH ACROSS OUR FAR EASTERN
PLAINS COUNTIES THROUGH 1 AM. STRONG OUTFLOW WINDS TO 50 MPH AND
HALF INCH HAIL ARE POSSIBLE AS THESE STORMS DROP SOUTH. LIGHT
RAINFALL WITH ISOLATED THUNDERSTORMS ARE ALSO CONTINUING OVER THE
MOUNTAIN REGIONS...AND SHOULD CONTINUE TO DISSIPATE THROUGH AROUND
2 AM. MOZLEY
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 319 PM MDT WED JUL 9 2014
ANOTHER ROUND OF TSRA OVER THE AREA TODAY...THOUGH SO FAR STORMS
HAVE BEEN WEAKER AND HIGHER BASED THAN YESTERDAY`S ACTIVITY...AS
PRECIPITABLE WATER HAS DECREASED SIGNIFICANTLY AND LOW LEVEL
MOISTURE HAS MIXED AT SOME LOCATIONS ALONG THE I-25 CORRIDOR. STILL
SOME FAIRLY STRONG INSTABILITY LEFT NEAR THE KS BORDER...WHERE
DEWPOINTS HAVE STAYED IN THE 50S...LEADING TO CAPES IN THE 1-2K J/KG
RANGE. FOR THE REST OF THE AFTERNOON AND EARLY EVENING...EXPECT SCT
TSRA TO CONTINUE OVER THE MTS...WITH A FEW STORMS DRIFTING ACROSS
THE VALLEYS AND INTERSTATE 25 CORRIDOR. LAST COUPLE RUNS OF THE HRRR
SUGGEST STORM INTENSITY WON`T BE PARTICULARLY STRONG...ESPECIALLY AS
STORMS MOVE AWAY FROM THE HIGHER TERRAIN. STILL...COULD BE A FEW
SMALL POCKETS OF BRIEF HEAVY RAIN...MAINLY NEAR THE NM BORDER WHERE
INSTABILITY IS A LITTLE BETTER. OVER THE FAR EASTERN PLAINS...WILL
HAVE TO WATCH FOR POTENTIAL STRONG/SEVERE CONVECTION DEVELOPING OVER
NERN CO BUILDING SOUTHWARD DURING THE EVENING...AS FAIRLY STRONG
SHEAR AND HEALTHY SURFACE S-SE FLOW MAY KEEP STORMS GOING PAST
SUNSET. HRRR SUPPORTS THIS IDEA WITH A FEW CELLS MOVING ACROSS
KIOWA/PROWERS COUNTIES 03Z-04Z. OVERNIGHT...MOST ACTIVITY WILL DIE
DURING THE EVENING...THOUGH WILL KEEP SOME LOW POPS GOING OVER THE
SAN JUANS WHERE MODELS SUGGEST DEEPER MOISTURE AND A FEW SHOWERS MAY
LINGER PAST MIDNIGHT.
ON THURSDAY...LITTLE CHANGE IN THE AIR MASS FROM TODAY...THOUGH WITH
SURFACE TROUGH PUSHING SLIGHTLY EAST TOWARD THE KS BORDER SUSPECT A
LITTLE BETTER MIXING WILL OCCUR ALONG AND EAST OF THE
MOUNTAINS...LEADING TO WEAKER/FEWER STORMS ON THE PLAINS/I-25
CORRIDOR. MOUNTAIN ACTIVITY LOOKS LITTLE CHANGED...WITH DEEPEST
MOISTURE ALONG THE CONTINENTAL DIVIDE ONCE AGAIN. MAX TEMPS WILL
LIKELY CREEP UP A FEW DEGREES OVER EASTERN SECTIONS WITH BETTER
MIXING...WITH READINGS NEAR OR A LITTLE OVER 100F FROM PUEBLO
EASTWARD.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 319 PM MDT WED JUL 9 2014
THE WEATHER PATTERN IS EXPECTED TO CHANGE VERY LITTLE AS A RIDGE OF
HIGH PRESSURE REMAINS OVER THE AREA THROUGH THE WEEKEND. MONSOON
MOISTURE TRAPPED UNDER THE RIDGE WILL PROVIDE THE FUEL FOR A DAILY
SHOT OF SHOWERS AND THUNDERSTORMS. CONVECTION WILL BE MAINLY
DIURNAL...BUT MAY START A BIT EARLIER OVER THE HIGHER TERRAIN DURING
THE LATE MORNING HRS...AS WELL AS LINGER INTO THE OVERNIGHT.
CONVECTION IS FORECAST TO BE SCATTERED OVER THE MTS...LIKELY OVER
THE PEAKS...AND MORE ISOLATED IN NATURE ACROSS THE PLAINS AND SAN
LUIS VALLEY.
THURSDAY NIGHT THROUGH SUNDAY...A SHORTWAVE PASSING TO THE NORTH
LATE THU WILL PUSH A COLD FRONT DOWN INTO EASTERN CO EARLY
FRI...THEN A REINFORCING BLAST OF COOLER MORE MOIST AIR COMES IN ON
SAT. THIS MEANS VERY WARM TEMPS FOR THE FORECAST AREA ON FRI...NEAR
NORMAL LEVELS ON SAT...THEN COOLER ON SUN. THIS WILL ALSO RESULT IN
SLIGHTLY HIGHER PCPN CHANCES FOR THE E PLAINS...ESPECIALLY ALONG THE
I25 CORRIDOR...FOR SAT AND SUN.
MONDAY THROUGH WEDNESDAY...LONG RANGE MODELS INTRODUCE A LARGE UPPER
LEVEL LOW PRESSURE SYSTEM THAT DROPS OUT OF CANADA AND HEADS TOWARDS
THE GREAT LAKES REGION ON MON...THEN SWEEPS IT TOWARDS THE NEW
ENGLAND STATES BY MIDWEEK. IF THIS OCCURS...IT MIGHT PUSH THE UPPER
RIDGE OVER THE ROCKIES MORE TO THE SW. FOR NOW...EXPECTED DAY TO DAY
CONVECTION CHANCES DO NOT SEEM TO CHANGE MUCH...SAVE FOR COOLER
TEMPS ON WED. MOORE
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1107 PM MDT WED JUL 9 2014
VFR CONDITIONS OVERNIGHT FOR ALL THREE TERMINALS. AFTERNOON AND
EVENING THUNDERSTORMS ARE POSSIBLE ACROSS THE MOUNTAINS ON
THURSDAY...WHICH WILL LIKELY MOVE OVER THE SAN LUIS VALLEY AND
PALMER DIVIDE. HAVE INCLUDED VCTS IN THE KALS AND KCOS TAFS TO
HIGHLIGHT THE POTENTIAL. THERE IS MUCH LESS CERTAINTY AT KPUB WITH
A LOW PROBABILITY OF A LATE AFTERNOON OR EVENING THUNDERSTORM.
MOZLEY
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MOZLEY
SHORT TERM...PETERSEN
LONG TERM...MOORE
AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
527 PM EDT THU JUL 10 2014
.SYNOPSIS...
A STATIONARY FRONTAL BOUNDARY WILL REMAIN OVER THE DELMARVA TONIGHT
BEFORE SLOWLY PUSHING SOUTH OF THE AREA FRIDAY. HIGH PRESSURE BUILDS
IN FROM THE NORTHEAST FRIDAY INTO SATURDAY. RETURN FLOW DEVELOPS
LATE IN THE WEEKEND AND EARLY NEXT WEEK AS HIGH PRESSURE MOVES
OFFSHORE AND AN STRONG UPPER LOW DIGS INTO THE UPPER MIDWEST. A COLD
FRONT WILL APPROACH THE EASTERN SEABOARD TUESDAY BEFORE MOVING
OFFSHORE BY WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
BACKDOOR COLD FRONT HAS CLEARED OUR CWA. BUT WITH TROFFING ALOFT,
THERE IS STILL SUFFICIENT INSTABILITY FOR SHOWERS AND
THUNDERSTORMS TO FORM. IF 7/8/14 WAS THE DAY THE HRRR AND COSPA
RAN TO THEIR AGENT AND RENEGOTIATE THEIR CONTRACTS, TODAY IS THE DAY
TO BE THANKFUL THE REVERSE CANT BE DONE. DIFFICULT MORE SUBTLE SCENARIO
WITH NONE OF THE MESOSCALE MODELS HANDLING/VERIFYING CONVECTION
WELL AND FALLING OFF TRACK RATHER QUICKLY WITHIN OUR CWA. WITH
SHORT WAVES STILL PROGGED TO PROGRESS THROUGH THE TROF, SFC BASED
INSTABILITY EXCEEDING 2K JOULES WEST, BOUNDARIES PROVIDING LIFT,
WE ARE GOING TO KEEP THE PRESENT FORECAST, WATCH, GOING UNTIL WE
SEE WHAT COMES OF THE CONVECTION EXITING THE ALLEGHENIES. ANY ESTF
UPDATES ARE GOING TO BE BASED ON ADJUSTING FOR TEMPS WHERE PCPN IS
OR JUST RECENTLY HAS OCCURRED.
A FLASH FLOOD WATCH HAS BEEN ISSUED FOR OUR DELMARVA AND SOUTHERN
NEW JERSEY COUNTIES WHERE IT HAS RAINED HEAVILY DURING THE DAY
TODAY, AND THE POTENTIAL FOR ADDITIONAL HEAVY RAIN EXISTS.
PW VALUES REMAIN HIGH WITH VALUES 1.75-2 INCHES ACROSS THE AREA.
MEANWHILE, THE MID-LEVEL TROUGH CONTINUES TO APPROACH THE AREA
FROM THE WEST AND SEVERAL VORTICITY IMPULSES WILL CONTINUE TO
SLIDE ACROSS THE AREA THROUGH THIS EVENING. ALL OF THIS COMBINED
WILL HELP ADDITIONAL SHOWERS AND THUNDERSTORMS DEVELOP. IT HAS
ALREADY RAINED ACROSS PORTIONS OF THE WATCH AREA TODAY, AND WHERE
IT HAS RAINED, IT`S BEEN VERY HEAVY WITH UP TO 3-4 INCHES IN SOME
AREAS IN AN HOUR OR TWO. WITH THE POTENTIAL FOR ADDITIONAL HEAVY
RAINFALL ACROSS THESE AREAS, WE HAVE ISSUED A FLASH FLOOD WATCH
THROUGH THIS EVENING.
THERE ARE SCATTERED SHOWERS AND THUNDERSTORMS MOVING THROUGH CENTRAL
AND NORTHEASTERN PENNSYLVANIA, THROUGH THESE HAVE BEEN MOVING AND
WILL LIKELY BE MORE DIURNAL IN NATURE AND SHOULD DISSIPATE AROUND
SUNSET; SO NO WATCH FURTHER NORTH.
WE EXPECT MUCH OF THE PRECIPITATION TO BEGIN TO DIMINISH LATER THIS
EVENING AND TOWARD MIDNIGHT AS INSATIABILITY WANES AND PW VALUES
BEGIN TO LOWER. THEREFORE THE WATCH ENDS AT LOCAL MIDNIGHT. HOWEVER,
WITH THE FRONT REMAINING NEARBY AND THE MID-LEVEL TROUGH STILL TO
OUR WEST, THERE WILL STILL BE THE POTENTIAL FOR A FEW SHOWERS AND
THUNDERSTORMS INTO FRIDAY MORNING.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
THE PESKY FRONTAL BOUNDARY IS EXPECTED TO PUSH BACK OFFSHORE ON
FRIDAY, AND STALL ACROSS THE OCEAN WATERS TO OUR EAST. PW VALUES
CONTINUE TO LOWER THROUGH THE DAY, BUT THE MID-LEVEL THROUGH WILL BE
MOVING OVERHEAD THROUGH THE DAY. THERE WILL REMAIN THE CHANCE FOR
ISOLATED-SCATTERED SHOWERS AND THUNDERSTORMS ACROSS THE AREA, WITH
THE BEST POTENTIAL ACROSS SOUTHERN NEW JERSEY AND SOUTHERN DELMARVA.
HIGHS ON FRIDAY WILL DEPEND ON HOW MUCH SUNSHINE WE GET, WITH CLOUDY
AREAS LIKELY BEING CLOSER TO THE COOLER MET GUIDANCE AND SUNNIER
AREAS CLOSER TO THE WARMER MAV GUIDANCE. FOR NOW, WE TOOK A BLEND OF
THE MAV/MET/MOSGUIDE FOR DAYTIME HIGHS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
SURFACE HIGH PRESSURE CENTERED JUST EAST OF NEW ENGLAND WILL PROVIDE
NICE WEATHER THROUGH SATURDAY. FRIDAY NIGHT WILL FEATURE CLEAR SKIES
AND COOL TEMPERATURES FOR THIS TIME OF YEAR, AND AN EASTERLY FLOW
WILL KEEP HIGHS IN THE 80S ON SATURDAY. CONDITIONS WILL BEGIN TO
DETERIORATE SOMEWHAT ON SUNDAY AS A FRONTAL BOUNDARY APPROACHES FROM
THE WEST. CLOUDS WILL BE ON THE INCREASE AND SHOWERS AND
THUNDERSTORM ACTIVITY WILL BECOME INCREASINGLY LIKELY FROM WEST TO
EAST AS THE DAY WEARS ON. THESE CLOUDS SHOULD KEEP THE HIGH
TEMPERATURES ON SUNDAY ONE OR TWO DEGREES COOLER THAN SATURDAY.
AN ANOMALOUSLY STRONG NRN STREAM CLOSED LOW IS FORECAST TO DIVE SOUTHWARD
FROM NEAR HUDSON BAY INTO THE UPPER MIDWEST EARLY NEXT WEEK, SETTING
UP A RATHER UNUSUAL PATTERN FOR THIS TIME OF YEAR. THE MID-ATLANTIC
REGION WILL BE SITUATED IN AN INCREASINGLY DIFFLUENT FLOW PATTERN
ALOFT ON THE SOUTHEASTERN PERIPHERY OF THE AMPLIFYING UPPER TROUGH
AND ON THE WESTERN PERIPHERY OF THE WESTERN ATLANTIC RIDGE. THE HEAT
AND HUMIDITY WILL RETURN MONDAY AND TUESDAY DURING THIS TIME AS
STRENGTHENING SOUTHWESTERLY FLOW AHEAD OF THE LOW BECOMES
ESTABLISHED OVER THE EASTERN CONUS. MAX TEMPS IN THE LOWER 90S
APPEAR LIKELY MONDAY AND TUESDAY. LEANED TOWARD THE SLOWER ECMWF
SOLUTION REGARDING THE ARRIVAL OF THE FROPA ON TUESDAY. RAISED MAX
TEMPS A FEW DEGREES FROM 12Z WPC GUIDANCE AS A SLOWER SOLUTION WOULD
KEEP THE PRE-FRONTAL WARM AIRMASS THAT IS CHARACTERIZED BY 850 MB
TEMPS NEAR 20C OVER THE AREA INTO TUESDAY. MAX TEMPS IN THE LOWER
90S OVER THE COASTAL MID-ATLANTIC REGION FOR ONE MORE DAY.
MONDAY AND TUESDAY BOTH LOOK TO BE A RATHER STORMY PERIOD FOR THE
AREA. THE FOCUS FOR CONVECTION APPEARS TO BE A PRE-FRONTAL/LEE
TROUGH ON MONDAY AND THE MAIN COLD FRONT FOR TUESDAY. FAVORABLE
DYNAMICS IN THE RIGHT ENTRANCE REGION OF AN UNSEASONABLY STRONG
UPPER-LEVEL JET STREAK AND AHEAD OF THE APPROACHING LONGWAVE TROUGH
ALSO LOOKS TO CONTRIBUTE TO SYNOPTIC LIFT OVER THE AREA ON TUESDAY.
THERE ARE STILL PLENTY OF DETAILS THAT NEED TO BE WORKED OUT THIS
FAR OUT, BUT THE POTENTIAL IS THERE FOR SEVERE THUNDERSTORM EVENTS
BOTH DAYS. SPC HAS DEPICTED THE AREA IN A DAY 6 SLIGHT RISK FOR
TUESDAY.
COLD FROPA LIKELY TUESDAY NIGHT OR EARLY WEDNESDAY. MUCH COOLER
AND DRIER CONDITIONS ARE FORECAST TO RETURN BEHIND THE COLD FRONT
BY WEDNESDAY. THE 12Z ECMWF INDICATES H8 TEMPS DROPPING INTO THE
SINGLE DIGITS BEHIND THE FRONT.
&&
.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
WE ARE FORECASTING VFR CONDITIONS FOR MOST AREAS THROUGH THE TAF
PERIOD. THE EXCEPTION IS MIV/ACY WHERE THERE HAVE BEEN MVFR AND EVEN
IFR CIGS/VSBYS ASSOCIATED WITH SHOWERS AND THUNDERSTORMS AND CLOUD
COVER FROM THE FRONTAL BOUNDARY OFF THE COAST. THERE COULD BE SOME
PATCH FOG OVERNIGHT TONIGHT AS WELL, ESPECIALLY FOR RDG/MIV AND
POSSIBLY ACY. THE REST OF THE TAF SITES WE DO NOT ANTICIPATE MUCH
FOG POTENTIAL. THERE REMAINS THE POSSIBILITY OF SHOWERS AND
THUNDERSTORMS LATE THIS AFTERNOON INTO THIS EVENING, ESPECIALLY FOR
SOUTHERN NEW JERSEY AND DELMARVA. WE HAVE KEPT ANY SHRA/TSRA GROUP
OUT OF THE TAFS EXCEPT AT MIV/ACY. THERE ARE A SOME
SHOWERS/THUNDERSTORMS MOVING ACROSS CENTRAL AND NORTHEASTERN
PENNSYLVANIA, BUT WE EXPECT THESE TO MOSTLY DISSIPATE AS THEY
APPROACH OUR AREA. IF THEY MAINTAIN THEMSELVES, WE WILL AMEND AS
NECESSARY.
WINDS WILL GENERALLY BE OUT OF THE EAST TO NORTHEAST TODAY, BEFORE
GOING LIGHT AND VARIABLE OVERNIGHT, THEN SETTLING BACK TO A
NORTHEAST DIRECTION AGAIN ON FRIDAY.
THE NAM SHOWS THE POSSIBILITY OF MVFR/IFR CIGS DEVELOPING OVERNIGHT
FOR ACY/MIV, SO WE WILL NEED TO MONITOR THIS IN CASE THIS COMES TO
FRUITION.
OUTLOOK...
FRIDAY NIGHT THRU SATURDAY NIGHT...POTENTIAL FOR IFR CIGS WITH
MARINE STRATUS TO IMPACT TERMINALS, PARTICULARLY ACY/MIV, FRIDAY AND
SATURDAY NIGHTS WITH ONSHORE FLOW. OTHERWISE VFR EXPECTED WITH DRY
CONDITIONS.
SUNDAY AND MONDAY...CHANCE FOR SHRA/TSRA BOTH DAYS. BETTER CHANCE
MAY BE MONDAY WITH A WELL-DEFINED SFC TROUGH DEVELOPING OVER THE
EASTERN SEABOARD. LOCAL/BRIEF RESTRICTIONS POSSIBLE.
TUESDAY...BETTER CHANCE FOR SHRA/TSRA TUESDAY AS A COLD FRONT
APPROACHES.
&&
.MARINE...
SUB-ADVISORY CONDITIONS ARE EXPECTED THROUGH TONIGHT AND FRIDAY WITH
A FRONTAL BOUNDARY DRAPED ACROSS THE WATERS. THERE REMAINS A CHANCE
FOR SHOWERS AND THUNDERSTORMS THROUGH FRIDAY; EXPECT HIGHER WINDS
AND WAVES NEAR THUNDERSTORMS.
OUTLOOK...
FRIDAY NIGHT THROUGH AND SATURDAY NIGHT...HIPRES BUILDS IN FROM THE
NORTHEAST STATES TO START THE WEEKEND. ONSHORE FLOW WILL BE LIGHT.
SUNDAY THROUGH TUESDAY...WINDS VEER, BECOMING SOUTHWESTERLY ON SUNDAY.
SOUTHWEST WINDS STRENGTHEN MONDAY BUT SHOULD REMAIN BELOW SCA
LEVELS. GUSTY SOUTHERLY WINDS AHEAD OF A COLD FRONT ON TUESDAY.
MARGINAL SCA POSSIBLE. CHANCE FOR SHRA/TSRA LATE SUNDAY. BETTER
CHANCE ON MONDAY AND TUESDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR NJZ016-
021>024.
DE...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR DEZ001>004.
MD...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR MDZ008-012-
015-019-020.
MARINE...NONE.
&&
$$
SYNOPSIS...KLEIN
NEAR TERM...GIGI/ROBERTSON
SHORT TERM...ROBERTSON
LONG TERM...KLEIN/MIKETTA
AVIATION...KLEIN/ROBERTSON
MARINE...KLEIN/ROBERTSON
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1242 AM EDT THU JUL 10 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THE AREA FROM THE NORTHWEST
OVERNIGHT BEFORE STALLING NEAR THE DELMARVA ON THURSDAY. HIGH
PRESSURE WILL BRIEFLY BUILD ACROSS THE NORTHEAST FRIDAY INTO
SATURDAY, BEFORE IT PUSHES OFFSHORE LATER IN THE DAY SATURDAY.
THEN A SERIES OF SURFACE TROUGHS WILL AFFECT THE AREA EARLY NEXT
WEEK, FOLLOWED BY A SLOW MOVING COLD FRONT TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
A FRONTAL BOUNDARY EXTENDED FROM AROUND RARITAN BAY SOUTHWESTWARD
ACROSS LOWER BUCKS COUNTY TO LANCASTER COUNTY AROUND MIDNIGHT. THE
BOUNDARY SHOULD CONTINUE TO SINK TO THE SOUTH OVERNIGHT.
SHOWERS WERE CONTINUING TO DEVELOP ALONG THE REMNANT OUTFLOW
BOUNDARIES FROM EARLIER CONVECTION FROM BERKS COUNTY AND THE
LEHIGH VALLEY INTO NORTHERN AND CENTRAL NEW JERSEY. THE ACTIVITY
WAS EXPERIENCING A WEAKENING TREND AND BASED ON THE HRRR THAT
TREND SHOULD CONTINUE WITH MOST OF THE PRECIPITATION DISSIPATING
BY ABOUT 300 AM.
WE WILL KEEP A SLIGHT CHANCE OF SHOWERS ACROSS MUCH OF THE
SOUTHERN PART OF OUR FORECAST AREA OVERNIGHT DUE TO THE FRONTAL
BOUNDARY. HOWEVER, THERE SHOULD BE NO OTHER SIGNIFICANT TRIGGERS
FOR PRECIPITATION SO WE WILL NOT MENTION THUNDER THERE.
MINIMUM TEMPERATURES ARE EXPECTED TO FALL INTO THE UPPER 50S AND
LOWER 60S IN THE ELEVATED TERRAIN UP NORTH IN THE WAKE OF THE
FRONTAL PASSAGE. MEANWHILE, LOW TEMPERATURES AHEAD OF THE FRONT
SHOULD DROP ONLY INTO THE UPPER 60S AND LOWER 70S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 AM FRIDAY/...
AN AMPLIFIED RIDGE OVER THE ATLANTIC OCEAN WILL BE ASSOCIATED
WITH AN OMEGA BLOCK THAT DEVELOPS OVER THE GREENLAND. UPSTREAM
RAMIFICATIONS OF THIS BLOCKING PATTERN WILL ALLOW THE UPPER LOW TO
REMAIN CUTOFF OVER QUEBEC AND ITS ASSOCIATED LONG WAVE TROUGH OVER
THE GREAT LAKES AND MIDWEST. OPERATIONAL MODEL GUIDANCE IN FAIRLY
GOOD AGREEMENT WITH THE POSITION OF THE COLD FRONT IN SRN
NJ/DELMARVA AT 12Z THURSDAY. THE FRONT WILL BECOME ORIENTED
PARALLEL TO THE S-SWLY STEERING FLOW IN BETWEEN THE UPSTREAM
TROUGH AND DOWNSTREAM RIDGE, CAUSING THE FRONTAL BOUNDARY TO STALL
OVER THE SRN THIRD OF THE CWA ON THURSDAY.
THE EXPECTED POSITION OF THE STATIONARY FRONT, POSITION OF THE
UPPER-LVL JET STREAK, AND TRACK OF A MID-LVL SHORTWAVE TROUGH ALL
CONTRIBUTE TO LARGE-SCALE LIFT FOR SRN NJ, DE, AND THE ERN SHORE
OF MD. POPS WERE INCREASED IN THESE SRN ZONES BUT DID NOT QUITE
HAVE THE FCST CONFIDENCE TO GO WITH LIKELY POPS DUE TO
UNCERTAINTIES IN TIMING OF PRECIP. CLOUDS EXPECTED TO LIMIT
CONVECTIVE POTENTIAL AND THUS THE SETUP FOR SEVERE TSTMS NOT
NEARLY AS FAVORABLE AS YESTERDAY AND TODAY.
CLOUD COVER AND SHOWER CHANCES DECREASE FARTHER NORTH. KEPT FCST
DRY NORTH OF INTERSTATES 195 AND 76.
MAX TEMP FCST WEIGHTED MORE WITH THE MET GUIDANCE. LIKED THE
GRIDDED OUTPUT WITH THE WARMEST TEMPS IN THE PHILA METRO AND
CENTRAL NJ, JUST NORTH, WHICH MAY BE JUST NORTH OF THE THICKER
CLOUD CLOVER.
&&
.LONG TERM /FRIDAY THROUGH THURSDAY/...
AT THE BEGINNING OF THE LONG TERM PERIOD, THE FRONTAL BOUNDARY
WILL REMAIN STALLED OUT OFFSHORE OF THE EAST COAST, WHILE PW
VALUES LOWER SLIGHTLY ACROSS THE AREA INTO FRIDAY. HOWEVER, THERE
COULD REMAIN JUST ENOUGH MOISTURE TO INTERACT WITH ANY SHORT
WAVE/VORTICITY IMPULSES THAT SLIDE ACROSS THE AREA WITHIN THE
BROAD TROUGH ALOFT THAT WILL REMAIN ACROSS THE EAST COAST. THE
GREATEST LIKELIHOOD IS ACROSS OUR FAR SOUTHERN NEW JERSEY AND
SOUTHERN DELMARVA ZONES, WHICH WILL BE CLOSER TO ANY INFLUENCE OF
THE FRONT TO OUR SOUTH AND WHERE ANY MOISTURE REMAINS POOLED.
HIGH PRESSURE WILL CONTINUE TO SLIDE ACROSS THE NORTHEAST FRIDAY
INTO FRIDAY NIGHT WHICH SHOULD HELP REINFORCE THE DRYING
POTENTIAL. THE HIGH BUILDS OFF THE NORTHEAST COAST SATURDAY, WHICH
WILL ALLOW A RETURN FLOW TO DEVELOP ACROSS THE AREA. WITH THIS
RETURN FLOW, MOISTURE RETURNS, AND WITH A VORTICITY IMPULSE
APPROACHING THE AREA SATURDAY, A FEW SCATTERED
SHOWERS/THUNDERSTORMS COULD DEVELOP. THESE WILL LIKELY BE MAINLY
AFTERNOON/DIURNALLY DRIVEN AND DIMINISH AFTER SUNSET.
AS WE MOVE INTO SUNDAY AND EARLY NEXT WEEK, WE ALMOST COPY AND
PAST THE FORECAST FROM THE LAST SEVERAL DAYS, AND PASTE IT INTO
THE FORECAST SUNDAY THROUGH WEDNESDAY PERIOD NEXT WEEK. AN AREA OF
LOW PRESSURE IS EXPECTED TO MOVE INTO SOUTHEASTERN CANADA, WHILE A
SERIES OF FRONTAL BOUNDARY CIRCLE AROUND THE LOW ACROSS THE GREAT
LAKES AND NORTHEAST. AHEAD OF THESE BOUNDARIES, A PRE-FRONTAL/LEE-
SIDE TROUGH IS POSSIBLE EACH DAY. SEVERAL SHORT WAVE/VORTICITY
IMPULSES ARE EXPECTED TO MOVE ACROSS OUR AREA EACH DAY, WHICH WILL
MAKE SHOWERS AND THUNDERSTORMS POSSIBLE EACH DAY UNTIL THE MAIN
COLD FRONT MOVES ACROSS THE AREA. THIS IS NOT EXPECTED UNTIL AT
LEAST TUESDAY NIGHT INTO WEDNESDAY. SO WE WILL HAVE AT LEAST A
CHANCE OF SHOWERS/THUNDERSTORMS EACH DAY FROM SUNDAY THROUGH
TUESDAY. EVEN THOUGH THERE IS A CHANCE EACH DAY, IT IS NOT
EXPECTED TO BE A COMPLETE WASHOUT EVERYWHERE EACH DAY. STILL,
INSTABILITY WILL BE INCREASING, AND PW VALUES WILL AS WELL. SO WE
IT REMAINS POSSIBLE FOR PERIOD OF HEAVY RAINFALL AND STRONG STORMS
AS WELL. ANY SEVERE POTENTIAL WILL DEPEND ON EACH DAY`S
INSTABILITY AND WIND/SHEAR PROFILES WHICH WILL BECOME MORE EVIDENT
IN THE DAYS TO COME.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
MAINLY VFR TONIGHT. THE EXCEPTION WILL BE IN LIGHT FOG WITH SOME
MVFR CONDITIONS.
THE COLD FRONT WILL PROGRESS SWD THRU THE TERMINALS TNGT AND WILL
BE ASSOCIATED WITH A WIND SHIFT FROM S TO NW AND EVENTUALLY N-NE
BY THU. ADDITIONAL SHRA EXPECTED IN VC OF ILG/MIV/ACY ON THU. TSRA
CHANCES WILL BE LOW.
OUTLOOK...
THURSDAY NIGHT-FRIDAY...MOSTLY VFR. A SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS, MAINLY ACROSS OUR SOUTHERN TAF SITES.
FRIDAY NIGHT-SATURDAY NIGHT...MVFR CIGS POSSIBLE WITH EASTERLY
FLOW.
SUNDAY-MONDAY...SHOWERS AND THUNDERSTORMS POSSIBLE, WHICH COULD
LOWER CIGS/VSBYS.
&&
.MARINE...
EXPECTING WIND SPEEDS TO DECREASE OVERNIGHT WITH 3 TO 4 FOOT SEAS
ON THE OCEAN.
WINDS SHOULD BE LIGHT ON THURSDAY WITH THE FRONTAL BOUNDARY
STALLING OVER THE WATERS. POTENTIAL FOR A FEW TSTMS ON THURSDAY
NEAR THE DELAWARE WATERS.
OUTLOOK...
THURSDAY NIGHT-FRIDAY...SUB-ADVISORY CONDITIONS EXPECTED. CHANCE
OF SHOWERS/THUNDERSTORMS, MAINLY SOUTHERN WATERS. HIGHER
WINDS/SEAS NEAR THUNDERSTORMS.
FRIDAY NIGHT-SATURDAY NIGHT...SUB-ADVISORY CONDITIONS EXPECTED.
SUNDAY-MONDAY...SUB-ADVISORY CONDITIONS EXPECTED, BUT WINDS WILL
BE INCREASING IN THE SOUTHWESTERLY FLOW AHEAD OF AN APPROACHING
FRONTAL BOUNDARY. CHANCE OF SHOWERS/THUNDERSTORMS. HIGHER
WINDS/SEAS NEAR THUNDERSTORMS.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ROBERTSON
NEAR TERM...IOVINO
SHORT TERM...KLEIN
LONG TERM...ROBERTSON
AVIATION...KLEIN/ROBERTSON
MARINE...KLEIN/KRUZDLO/ROBERTSON
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
134 AM EDT THU JUL 10 2014
.PREV DISCUSSION... /ISSUED 755 PM EDT WED JUL 9 2014/
UPDATE...
SCATTERED THUNDERSTORMS WILL OCCUR MAINLY OVER CENTRAL GA ALONG AND
SOUTH OF A WEAK FRONTAL BOUNDARY FROM FRANKLIN THROUGH CONYERS TO
ATHENS THIS EVENING. AN UPPER LEVEL DISTURBANCE CONTINUES TO TRIGGER
ADDITIONAL SCATTERED THUNDERSTORMS OVER EXTREME NORTH GA FROM TRENTON
TO DALTON. THE STORMS WILL GENERALLY MOVE EAST AT 15 KTS BEFORE
DISSIPATING BY MIDNIGHT. THE POPS OVER THE ATLANTA METRO AREA HAVE
BEEN LOWERED INTO THE 30-40 PERCENT RANGE AND ALL OF NORTH GA WILL
DROP TO AROUND 20 PERCENT AFTER MIDNIGHT.
16/39
SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
COLD FRONT IS PUSHING INTO NORTHWEST GEORGIA AT AFD TIME...WITH A
LINE OF CONVECTION ROUGHLY FROM ATHENS TO THE SOUTH SIDE OF ATLANTA
ALONG A WEAK SURFACE CONVERGENCE ZONE AND DIFFERENTIAL HEATING
BOUNDARY /FROM MIDLEVEL CLOUDS UP NORTH/. DEEP UPPER TROUGH REMAINS
IN PLACE OVER THE EASTERN PORTION OF THE COUNTRY BUT WILL BEGIN TO
LIFT TOWARD THE END OF THE SHORT TERM...WITH THE FRONT PROGGED TO
LINGER ACROSS CENTRAL GEORGIA THROUGH THURSDAY.
CONCERN FOR THIS EVENING WILL BE MAINLY ABOUT CONVECTION...NAMELY
COVERAGE AND INTENSITY. EXPECT CHANCES TO REMAIN PRETTY HIGH AS DEEP
LAYER MOISTURE HAS INCREASED AHEAD OF THE FRONT. BUFR SOUNDINGS
REMAIN FAIRLY SATURATED THROUGH THE EVENING AND OVERNIGHT HOURS AND
WITH PLENTIFUL SBCAPE...IT IS MAINLY JUST A MATTER OF WHERE
CONVECTION WILL BE ABLE TO GET GOING. CANNOT RULE OUT ISOLATED
SEVERE STORMS WITH MARGINALLY SEVERE HAIL AS THE MAIN THREAT. DCAPE
VALUES ARE BETWEEN 1000-1300 J/KG ACROSS NORTH GEORGIA AND ALSO
ACROSS PORTIONS OF CENTRAL GEORGIA...WITH AREAS FROM METRO ATLANTA
TO ATHENS TOO LOW FOR MUCH CONCERN. NEW TRENDS IN RAP DATA KEEP THE
HIGH DCAPE VALUES IN PLACE DOWN SOUTH BUT DIMINISH THEM UP NORTH
THROUGH THE AFTERNOON...SO BEST CHANCE FOR MARGINAL SEVERE WOULD
LIKELY BE ACROSS PORTIONS OF CENTRAL GEORGIA.
WIDESPREAD CLOUD COVER AND PLENTIFUL SURFACE MOISTURE WILL KEEP HIGH
TEMPS TOMORROW A FEW DEGREES LOWER THAN NORMAL...WITH NEAR-NORMAL
LOWS.
TDP
LONG TERM /FRIDAY THROUGH WEDNESDAY/...
LONG WAVE TROUGH TO CONTINUE TO FILL OVER ERN CONUS FRI THRU SUN
WHILE E-W ORIENTED RIDGE ALOFT BUILDS OVER SRN STATES. SHOULD SEE
WARMING TEMPS AND LOWER POPS IN THIS PATTERN. ISOLD SHRA/TSRA
STILL LIKELY BUT LESS COVERAGE THAN PREVIOUS DAYS. LARGE UPPER
VORTEX AND TROUGH PROGGED BY 12Z MED RANGE MODELS TO SWING SOUTH
FROM CANADA INTO ERN CONUS AGAIN MONDAY WITH PERIPHERY OF
WESTERLIES AND WEAK FRONT DIPPING INTO GA ON TUES. EXPECT RETURN
TO HIGHER POPS AND SLIGHTLY COOLER TEMP TUES/WED. MADE ONLY
SMALL MODIFICATIONS TO POPS/WX AND TEMPS WITH MODEST ADJUSTMENTS
TOWARD HPC GUIDANCE.
SNELSON
PREV LONG TERM DISCUSSION... /ISSUED 148 PM EDT WED JUL 9 2014/
/VALID THURSDAY NIGHT THROUGH TUESDAY/...
THURSDAY AND FRIDAY....EXTENDED PERIOD BEGINS WITH EASTERN US TROF
CENTERED NEAR 85 WEST AND REMNANT FRONTAL BOUNDARY DRAPED ACROSS
CENTRAL GA. BOTH THE ECMWF AND GFS IN GOOD AGREEMENT WITH BOTH THE
LOCATION OF THE FRONT AND DEPTH OF THE EASTERN TROF. END RESULT IS
MOSTLY DIURNAL CONVECTION PARTICULARLY NEAR THE BOUNDARY ALONG AND
SOUTH OF I85 WITH BEST CHANCES ON THURSDAY. MODEL CAPE VALUES ARE
MODEST AND TYPICAL FOR SUMMERTIME PATTERN...HOWEVER PRECIPITABLE
WATER VALUES PEAK ACROSS THE AREA ON THURSDAY BETWEEN 1.8 AND 2.0
INCHES WHICH COULD RESULT IN SOME EFFICIENT RAIN PRODUCING STORMS.
DRIER AIR WORKS IN BEHIND THE FRONT ON FRIDAY SQUASHING THE BEST
RAIN CHANCES TO THE SOUTH AND EAST PORTION OF THE AREA...I.E. CSG
TO MCN AND POINTS SOUTH NEAR THE REMNANT FRONT.
WEEKEND...THE GENERAL PATTERN PERSISTS INTO THE WEEKEND ACROSS THE
EASTERN U.S. WITH THE TROF AXIS SHIFTING SLIGHTLY EAST OF GA
BY SATURDAY AND SOME MID LEVEL RIDGING TRYING TO NOSE IN FROM THE
WEST...WHILE THE REMNANT FRONT IS ALL BUT A DISTANT MEMORY. END
RESULT WILL BE NEAR TO SLIGHTLY BELOW CLIMO POP CHANCES BOTH
SATURDAY AND SUNDAY. CAVEAT HERE IS THAT PW VALUES SOAR UP TO NEAR
OR SLIGHTLY ABOVE 2.0 INCHES MAKING FOR A MUGGY WEEKEND. STILL
THINK THE GREATEST CHANCES WILL BE SOUTH AND EAST CLOSER TO WHERE
SEA BREEZE ACTIVITY HAS THE BEST INFLUENCES LATE IN THE AFTERNOON.
MONDAY AND TUESDAY...GFS AND ECMWF SLIGHTLY DIFFERENT BUT STILL
GENERALLY AGREE THAT THE LARGER SCALE TROF WILL BE REINFORCED
ACROSS THE REGION WITH ANOTHER FRONT APPROACHING. END RESULT WILL
BE INCREASED POP CHANCES ON MONDAY AND PARTICULARLY TUESDAY. MUCH
CAN HAPPEN BETWEEN NOW AND THEN SO WILL TREND HIGHER BUT NOT GO
OVERBOARD.
STELLMAN
&&
.AVIATION...
06Z UPDATE...
CONVECTION HAS MOSTLY CLEARED OUT THIS MORNING...A FEW MVFR CLOUDS
MAY DEVELOP TOWARDS SUNRISE...BUT NOT CONFIDENT THAT THE MVFR DECK
WILL GO BKN. DIURNAL CU EXPECTED TO DEVELOP BY MID MORNING AND
SETTLE BETWEEN 040 AND 045. STALLED FRONTAL BOUNDARY SHOULD BE
JUST TO THE SOUTH OF ATL...AND SHOULD PROVIDE THE MAIN FOCUS FOR
TSRA TODAY. HOWEVER...ENOUGH CONFIDENCE SHRA/TSRA DEVELOPMENT WILL
BE CLOSE ENOUGH TO THE AIRPORT FOR A PROB30.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM CONFIDENCE ALL ELEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 89 69 91 68 / 50 30 30 20
ATLANTA 86 71 89 70 / 40 30 30 10
BLAIRSVILLE 82 63 84 61 / 40 30 20 20
CARTERSVILLE 86 67 89 65 / 40 30 20 10
COLUMBUS 90 73 92 72 / 60 30 30 10
GAINESVILLE 85 69 88 68 / 40 30 30 20
MACON 90 70 91 69 / 60 40 40 20
ROME 87 67 90 65 / 40 20 20 10
PEACHTREE CITY 87 68 89 67 / 50 30 30 10
VIDALIA 92 73 90 72 / 60 40 60 50
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS DODGE CITY KS
241 AM CDT Thu Jul 10 2014
...Updated for Long Term...
.SHORT TERM...(This evening through Thursday)
ISSUED AT 205 PM CDT WED JUL 9 2014
The main challenge in the forecast tonight and Thursday is
precipitation chances, extent, and thunderstorm severity.
Surface-based thunderstorms are expected to develop across northeast
Colorado in vicinity of, or just downstream of Cheyenne Ridge. The
former runs (00Z) of the WRF-ARW and WRF-NMMB cores suggested a
small MCS would develop and roll southeast toward far west-central
Kansas. The latest 12Z runs of both the models, however, are less
aggressive with this idea. That being said, the HRRR (using WRF-ARW
core) late morning runs insist on northeast Colorado activity
evolving southeast through the evening across northeastern Kansas
and eventually into our far northwestern zones (Syracuse to Scott
City). We will maintain some Chance POPs in the far west-central
Kansas counties north of Hwy 50 and generally west of Hwy 283
through the evening.
Another MCS will either roll south-southeast out of Nebraska and
interact with the western MCS or remain a separate entity all
together and redevelop around 04-06Z across north central/central
Kansas along a strengthening zone of warm frontogenesis in the
850-750mb layer. We will have some 40 POPs from Hays to Pratt in the
05-12Z time frame, but these may need to be raised early this
evening if short term trends favor a more western scenario for
potential MCS. The overall severe weather threat looks fairly
minimal, despite a SLGT risk being issued by SPC. Any large hail
threat would be confined to areas of far west-central Kansas (but
more likely across northeastern Colorado and northwestern Kansas)
with strong straight-line winds to 65 mph the most likely threat
with any bowing segments during the mid to late evening hours. After
that, a very heavy rain threat will develop during the overnight
hours across central Kansas. It remains to be seen, though, how far
west the core of the nocturnal MCS will be. It seems most likely
this will stay across portions of central and south central Kansas
just east of our forecast area (east of a Hays to Pratt line).
Going in to the day Thursday, a warmer day is forecast with warmer
overall temperatures in the lower troposphere (to +29C at 850mb as
far east as the Hwy 283 corridor). This should allow surface
temperatures late afternoon reaching close to, if not 100F
(especially along/west of Hwy 83 where evapotransporation will be
less). A fairly strong gradient will yield a windier day with
south-southwest winds 20 to 23 knots sustained in the afternoon.
.LONG TERM...(Friday through Wednesday)
ISSUED AT 239 AM CDT THU JUL 10 2014
For Friday into Sunday, a broad area of upper level high pressure
begins to weaken ahead of a strong upper level low moving southward
from Central Canada and into the Upper Midwest. Weak surface low
pressure will continue in far western Kansas then move slowly into
central Kansas by Sunday. Some moisture convergence along the trough
may be enough to set off a few thunderstorms mainly far west on
Friday then a slight chance into much of western Kansas into Sunday.
High temperatures will be warm and around 100 on Friday, and mid to
upper 90s Saturday, then low to mid 90s for Sunday. Overnight lows
will continue mild and in the low to mid 70s into Sunday morning.
For Monday into mid week next week, the upper level low and
associated cold upper trough will continue to build southward into
the Upper Midwest and Central Plains with a cooling trend. Highs
cool from around 90 on Monday into the 70s and 80s for Tuesday into
Wednesday. Some small chances for thunderstorms continue with the
best chances with and behind a cold front on Monday night and
Tuesday. Overnight lows look to be in the 60s.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
ISSUED AT 1251 AM CDT THU JUL 10 2014
Winds will generally stay southerly with VFR conditions at
DDC/GCK through the period as a lee trough remains in the lee of
the Rockies. An outflow boundary will pass trough KGCK just after
06z (now) and could temporarily shift winds to northwest. At KHYS,
thunderstorms will be in vicinity through 08z as low to mid level
warm advection persists early this morning, with winds persisting
from the southeast. Even at KHYS, CIGS and VISBYS will generally be
VFR except briefly lower in any thunderstorms.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 97 72 98 72 / 10 0 10 10
GCK 98 71 99 71 / 10 0 10 20
EHA 98 71 97 71 / 0 0 10 20
LBL 100 71 99 72 / 0 0 10 10
HYS 93 72 99 73 / 10 10 20 20
P28 93 72 98 75 / 20 0 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Umscheid
LONG TERM...Kruse
AVIATION...Finch
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
102 AM CDT Thu Jul 10 2014
...Updated for aviation discussion...
.SHORT TERM...(This evening through Thursday)
ISSUED AT 205 PM CDT WED JUL 9 2014
The main challenge in the forecast tonight and Thursday is
precipitation chances, extent, and thunderstorm severity.
Surface-based thunderstorms are expected to develop across northeast
Colorado in vicinity of, or just downstream of Cheyenne Ridge. The
former runs (00Z) of the WRF-ARW and WRF-NMMB cores suggested a
small MCS would develop and roll southeast toward far west-central
Kansas. The latest 12Z runs of both the models, however, are less
aggressive with this idea. That being said, the HRRR (using WRF-ARW
core) late morning runs insist on northeast Colorado activity
evolving southeast through the evening across northeastern Kansas
and eventually into our far northwestern zones (Syracuse to Scott
City). We will maintain some Chance POPs in the far west-central
Kansas counties north of Hwy 50 and generally west of Hwy 283
through the evening.
Another MCS will either roll south-southeast out of Nebraska and
interact with the western MCS or remain a separate entity all
together and redevelop around 04-06Z across north central/central
Kansas along a strengthening zone of warm frontogenesis in the
850-750mb layer. We will have some 40 POPs from Hays to Pratt in the
05-12Z time frame, but these may need to be raised early this
evening if short term trends favor a more western scenario for
potential MCS. The overall severe weather threat looks fairly
minimal, despite a SLGT risk being issued by SPC. Any large hail
threat would be confined to areas of far west-central Kansas (but
more likely across northeastern Colorado and northwestern Kansas)
with strong straight-line winds to 65 mph the most likely threat
with any bowing segments during the mid to late evening hours. After
that, a very heavy rain threat will develop during the overnight
hours across central Kansas. It remains to be seen, though, how far
west the core of the nocturnal MCS will be. It seems most likely
this will stay across portions of central and south central Kansas
just east of our forecast area (east of a Hays to Pratt line).
Going in to the day Thursday, a warmer day is forecast with warmer
overall temperatures in the lower troposphere (to +29C at 850mb as
far east as the Hwy 283 corridor). This should allow surface
temperatures late afternoon reaching close to, if not 100F
(especially along/west of Hwy 83 where evapotransporation will be
less). A fairly strong gradient will yield a windier day with
south-southwest winds 20 to 23 knots sustained in the afternoon.
.LONG TERM...(Thursday night through Wednesday)
ISSUED AT 246 PM CDT WED JUL 9 2014
Thursday night/Friday:
Minimums overnight Thursday will be quite mild - 70s - as southerly
winds continue through the overnight in association with continued
surface lee troughing.
Friday will be a hot day with max values at 97-100F. There will be
a slight chance for tstms from Hugoton to Hays and points west, but
convection may remain out of the area and limited to eastern Colorado
and into southwest Nebraska. Another mild night with widespread 70s
for lows is expected heading into Saturday morning.
Saturday and beyond:
A slightly better chance of coverage of storms is expected Saturday
as a frontal boundary sinks farther to the south across Kansas. Ahead
of the front, temperatures will be quite hot with values around 100F.
A weak cool down is expected Sunday as the front heads south and slightly
cooler 850-hPa temperatures advect across the region. Will have to watch
out for convection across the western zones in this upslope flow pattern.
The EC indicates another shot for an MCS Monday, as northwesterly flow
aloft and low-level upslope flow continues across the High Plains.
The best chance for precip area-wide is expected Tuesday as a rather
cold air mass (for July standards) moves across the Plains. The EC has
been very consistent with this cool down and associated precipitation.
850-hPa temperatures by the middle portion of next decrease as low as
8-10C! Very pleasant and highly abnormal Summer weather in regards to
temperatures is possible in about a week from now with highs in the
70/80s and lows possibly in the 50s! The front could slow down, so exact
timing is in question. Stuck with the allblend temperature solution
for now.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
ISSUED AT 1251 AM CDT THU JUL 10 2014
Winds will generally stay southerly with VFR conditions at
DDC/GCK through the period as a lee trough remains in the lee of
the Rockies. An outflow boundary will pass trough KGCK just after
06z (now) and could temporarily shift winds to northwest. At KHYS,
thunderstorms will be in vicinity through 08z as low to mid level
warm advection persists early this morning, with winds persisting
from the southeast. Even at KHYS, CIGS and VISBYS will generally be
VFR except briefly lower in any thunderstorms.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 72 98 73 99 / 0 10 10 20
GCK 71 99 72 98 / 0 20 20 20
EHA 71 97 71 94 / 0 20 20 10
LBL 71 99 72 98 / 0 10 20 10
HYS 72 99 72 97 / 10 20 20 30
P28 72 98 74 100 / 0 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Umscheid
LONG TERM...Sugden
AVIATION...Finch
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
138 PM EDT THU JUL 10 2014
.SYNOPSIS...
A FRONTAL BOUNDARY STALLS OVER THE REGION TODAY THROUGH FRIDAY.
A WEAK AREA OF LOW PRESSURE MOVES NORTHEAST ALONG THIS BOUNDARY
TONIGHT THEN PUSHES OFFSHORE FRIDAY. HIGH PRESSURE BUILDS SOUTH
ACROSS THE MID ATLANTIC REGION THIS WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATED TO ADD SEVERE TSTM WATCH FOR SE VA/NE NC.
PREVIOUS DISCUSSION...
LATEST ANALYSIS SHOWING FRONTAL BOUNDARY STALLED OVER WRN PORTIONS
OF THE CWA WITH AN AREA OF SHOWERS/EMBEDDED TSTMS DEVELOPING ALONG
THE FRONT ACRS MECKLENBURG/LUNENBURG AS OF 11 AM. VERY MOIST
AIRMASS IN PLACE ACRS THE REGION WITH PWAT VALUE OVER 2" ON 12Z
WAL SOUNDING (AND 1.75-2" AT GSO). 12Z NAM BRINGS PRECIP FARTHER
NORTH THAN PREVIOUS RUNS AND IT MAY BE ONTO SOMETHING AS IT IS
VERIFYING WELL THUS FAR. HAVE THUS INCREASED POPS TO 70% OVER MUCH
OF CENTRAL VA AS FAR N AS METRO RICHMOND THIS AFTN (WELCOME
RAINFALL HERE). SATELLITE TRENDS SUGGEST LITTLE CLEARING THIS
AFTN...WITH THE POSSIBLE EXCEPTION OF FAR SE VA/NE NC WHERE A
BRIEF PERIOD OF PARTIAL CLEARING MAY OVERSPREAD THE REGION OVER
THE NEXT FEW HRS BEFORE TSTMS REDEVELOP.
MAIN CONCERN TODAY WILL BE FOR HEAVY RAIN AND POSSIBLE FLASH
FLOODING HOWEVER SOME STRONG TO SEVERE STORMS WILL BE POSSIBLE IN
FAR SE VA/NE NC WHERE INSTABILITY IS A LITTLE HIGHER AND DUE TO
DEEP LAYER SHEAR 0-6 KM OF 30-35 KT. MAINLY A STRONG WIND THREAT
BUT AN ISOLATED VERY BRIEF WEAK TORNADO NOT OUT OF THE QUESTION
GIVEN THE LOW LEVEL BOUNDARY. IR SATELLITE SHOWS DEEP MOISTURE
PLUME FROM THE SW AND UPPER JET IS IN A FAVORABLE POSITION (RRQ
FORCING) TO SUPPORT LIKELY POPS MOST AREAS THIS AFTN AND TONIGHT.
IN ADDITION..SHOULD SEE TRAINING OF STORMS DUE TO LOW LEVEL SW JET
BEING NEARLY PARALLEL AND SIMILAR IN MAGNITUDE TO THE FLOW ALOFT
(LOW MBE VALUES). MUCH OF HAMPTON ROADS AND NE NC RECEIVED 2" OR
MORE OF RAINFALL OVER THE PAST 24 HRS AND MAY NEED TO CONSIDER A
FLASH FLOOD WATCH THIS AFTN THROUGH FRI MORNING IN THESE AREAS BUT
CONFIDENCE TOO LOW IN PLACEMENT OF HEAVIEST PRECIP (ESPECIALLY
GIVEN THE LATEST NAM KEEPING HEAVIER AMTS FARTHER INLAND/NW). WILL
CONTINUE MENTION OF LCLLY HEAVY RAINFALL THREAT IN HWO (AND SEVERE
THREAT OVER FAR SE VA/NE NC). LOWERED MAX TEMPS A FEW DEGREES WITH
HIGHS MAINLY IN THE LOWER-MID 80S.
S/W ENERGY TRACKS NE ALONG THE BNDRY TONIGHT. THIS WILL NOT ONLY
ENHANCE CONVECTION CHCS OVERNIGHT BUT SHOULD KEEP THE THREAT OF
PCPN GOING THROUGH THE NIGHT...PARTICULARLY ACRS SE VA/NE NC.
POPS WOULD LIKELY HAVE TO BE RAISED FURTHER WEST IF NAM VERIFIES.
LOWS M60S FAR NW TO LWR-MID 70S SE.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
SYSTEM LINGERS ALONG COASTAL AREAS FRIDAY MORNING BEFORE SLOWLY
EXITING OFF THE COAST DURING THE AFTN. DATA SHOWS PLENTY OF MSTR
ARND ALONG WITH SOME INSTABILITY TO INCLUDE CHC POPS THROUGH THE
DAY WITH THE HIGHEST POPS SERN AREAS. HIGHS GNRLY IN THE M80S. SCT
EVENING POPS FRI NIGHT...OTW BCMG PT CLDY. LOWS 65-70 F.
MODELS INDICATING THE FRONT WASHES OUT / DISSIPATES ACROSS THE AREA
SAT. KEPT A 20-30% POP OVER THE FAR NW AND IN SE VA/NE NC. PARTLY
SUNNY WITH HIGHS IN THE M-U80S.
QPF NXT 72 HRS AVGG 2/3RDS TO 1 IN ACROSS NWRN AREAS...1 TO 1.5
IN ACROSS CNTRL AREAS...1.5 TO 2.5 ACROSS SERN VA/NE NC.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AMPLIFIED UPPER FLOW OVER THE HIGHER LATITUDES WILL PUSH ANOTHER
ANOMALOUS TROUGH INTO THE NERN CONUS EARLY NEXT WEEK. THE RESULT
WILL BE BELOW NORMAL TEMPS AND WET CONDITIONS FROM THE UPPER MIDWEST
TO THE OH VALLEY. HOWEVER...THE LOCAL AREA REMAINS SEASONABLY WARM
AS MUCH OF THE COOLER AIR WILL BE LOCKED WEST OF THE CNTRL
APPALACHIANS.
FOR THE LATTER HALF OF THE WEEKEND...ONGOING RETURN FLOW ON THE
BACKSIDE OF HIGH PRESSURE ANCHORED OVER THE WRN ATLANTIC WILL RESULT
IN SLIGHTLY WARMER TEMPS AND DEWPOINTS SUN COMPARED TO SAT.
THICKNESSES YIELD TEMPS RIGHT AROUND 90 DEGS. A COLD FRONT WILL PUSH
INTO THE GREAT LAKES REGION SUN WITH SFC TROUGHING DEVELOPING OVER
THE LOCAL AREA. THETA-E ADVECTION AND A MOIST BL WILL RESULT IN
MLCAPE VALUES ~1500 J/KG. MODEL DERIVED PRECIP WATERS RANGE FROM
1.75 TO 2 INCHES. WHILE MOISTURE/INSTABILITY LOOK FAVORABLE...BEST
DYNAMICS/FORCING REMAINS WELL WEST OF THE AREA WITH THE BETTER
HEIGHT FALLS AND STRONGER WINDS ALOFT. SHEAR IS ALSO UNIMPRESSIVE
AND SOUNDINGS DEPICT SUBSIDENCE/WARM AIR ALOFT. WILL CARRY CHANCE
POPS IN THE NW...TAPERING OFF TO SILENT IN THE SE. BETTER COVERAGE
EXPECTED MON AS HEIGHT FALLS AND INCREASING WINDS ALOFT PROVIDE
BETTER FORCING FOR ASCENT AND COOLER MID-LEVEL TEMPS. COLD FRONT IS
EXPECTED TO REACH THE CNTRL APPALACHIANS LATE MON...SHARPENING THE
THERMAL TROUGH OVER THE LOCAL AREA. WARMER TEMPS AND DEWPOINTS WILL
PUSH MLCAPE VALUES HIGHER...BUT SHEAR REMAINS MARGINAL (AOB 20 KT).
THE RESULT WILL BE SCT AFTERNOON SHOWERS/THUNDERSTORMS ACROSS MUCH
OF THE REGION. COLD FRONT DROPS INTO THE REGION TUES-TUES NIGHT.
EXACT TIMING OF THE FRONT WILL IMPACT SENSIBLE WEATHER OVER THE
LOCAL AREA. WILL TREND TOWARD A BLEND BTWN THE MEDIUM RANGE
GUIDANCE...KEEPING THE BEST POPS ALONG THE COAST TUES. BASED ON THE
AIRMASS...WILL ALSO CARRY SLIGHT CHANCE POPS MON NIGHT-TUES MORNING
AS THE FRONT CROSS THE REGION. UPPER LOW BEGINS TO EJECT FROM THE
GREAT LAKES REGION TUES INTO SE CANADA...SLOWING THE FRONT AS IT
PUSHES OFFSHORE TUES NIGHT-WEDS MORNING. CONFIDENCE IS NOT HIGH
ATTM...BUT WILL HANG ON TO SLIGHT CHANCE POPS ALONG THE COAST WEDS
BASED ON THE FRONT LIKELY STALLING OFFSHORE.
TEMPS WILL REMAIN AROUND SEASONABLE NORMS...WARMING INTO THE UPPER
80S-LOW 90S THRU THE PERIOD. ANTICIPATE TUES TO BE THE WARMEST IN
ADVANCE OF THE FRONT...WITH HIGHS GENERALLY IN THE LOW 90S.
OVERNIGHT LOWS WILL GENERALLY BE IN THE UPPER 60S-LOW 70S...WITH MID
70S NEAR THE COAST.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
TSTMS CONTINUE TO DEVELOP ALONG THE ALBEMARLE SOUND. THIS IS ALONG
THE OUTFLOW FROM THE EARLIER CONVECTION. LOOKING AT THE HRRR THINK
THESE WILL FINALLY END BY AROUND 14Z. WILL HAVE A TEMPO GROUP AT
KECG AS THESE TSTMS COULD MOVE ACROSS THERE AT TIMES. UPPER TROF
CONTINUES ACROSS THE AREA TODAY. THERE WILL BE SEVERAL BOUNDARIES
ACROSS THE AREA WHICH COULD FOCUS CONVECTION THIS AFTERNOON INTO
TONIGHT. ALL MODELS AGREE ON CONVECTION DEVELOPING JUST NOT SURE
WHETHER TO THE WEST MOSTLY RECEIVES IT OR BACK ACROSS THE
SOUTHEAST. MOST HI RES MODELS ARE LEANING TOWARD SE VA AND NE NC
SO WILL PUT A TEMPO GROUP IN THAT AREA THIS AFTERNOON. HOWEVER
THINK MOST AREAS WILL GO TO MVFR OR EVEN IFR IN TSTMS SOMETIME
THIS AFTERNOON OR TONIGHT. WITH DIMINISHING FLOW BY TONIGHT ANY
THUNDERSTORMS THAT DO FORM WILL BE SLOW TO MOVE. OUTSIDE OF THE
PRECIPITATION EXPECT VFR CONDITIONS WITH SOME CLOUDS AROUND 10
THOUSAND FEET.
FRONT CROSSES AREA BY FRIDAY...LEAVING FRI NGT/SAT DRY ATTM. NEXT
FRONT COULD BRING THE POTENTIAL FOR MORE SHWRS/TSTMS TO THE REGION
LATE SUNDAY OR MONDAY.
&&
.MARINE...
SUB-SCA CONDITIONS ARE EXPECTED OVER THE WATERS THROUGH THE WEEK. A
WEAK TROF IS TO THE WEST OF THE WATERS KEEPING MAINLY A LIGHT
SOUTHERLY WIND OVER THE WATERS. A WEAK LOW PRESSURE SYSTEM WILL MOVE
ALONG THIS BOUNDARY TONIGHT AND FRIDAY. THIS WILL ALLOW THE WINDS TO
BE MORE SOUTHEAST AT TIMES. AFTER THE LOW MOVES PAST FRIDAY NIGHT
THE TROF WILL MOVE OFF THE COAST SATURDAY. WILL HAVE LIKELY
THUNDERSTORMS THIS AFTERNOON AND TONIGHT OVER THE SOUTHERN WATERS
WITH A CHANCE ACROSS THE NORTHERN WATERS.SCATTERED SHOWERS AND
THUNDERSTORMS WILL CONTINUE ACROSS THE WATERS FRIDAY INTO FRIDAY
NIGHT. WINDS WILL BECOME MORE WEST TO NORTH OVER THE WEEKEND. FLOW
VEERS TO THE SOUTH SUN...REMAINING SUB SCA AT 10-15 KT. SEAS REMAIN
2-3 FT. LOW PRESSURE LIFTS INTO THE GREAT LAKES REGION MON AS A COLD
FRONT PUSHES INTO THE OH VALLEY. GRADIENT WILL STRENGTHEN SLIGHTLY
OVER THE WATERS SUN NIGHT-MON...BUT REMAINS SUB-SCA. PERSISTENT SLY
FLOW WILL PUSH SEAS TO 4 FT IN THE NRN WATERS...BUT ANTICIPATE SEAS
TO REMAIN UNDER 5 FT. COLD FRONT CROSSES THE WATERS TUES NIGHT-WED
MORNING.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LKB
NEAR TERM...LKB
SHORT TERM...LKB/MPR
LONG TERM...SAM
AVIATION...JAB
MARINE...JAB
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1252 PM EDT THU JUL 10 2014
.SYNOPSIS...
A FRONTAL BOUNDARY STALLS OVER THE REGION TODAY THROUGH FRIDAY.
A WEAK AREA OF LOW PRESSURE MOVES NORTHEAST ALONG THIS BOUNDARY
TONIGHT THEN PUSHES OFFSHORE FRIDAY. HIGH PRESSURE BUILDS SOUTH
ACROSS THE MID ATLANTIC REGION THIS WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
LATEST ANALYSIS SHOWING FRONTAL BOUNDARY STALLED OVER WRN PORTIONS
OF THE CWA WITH AN AREA OF SHOWERS/EMBEDDED TSTMS DEVELOPING ALONG
THE FRONT ACRS MECKLENBURG/LUNENBURG AS OF 11 AM. VERY MOIST
AIRMASS IN PLACE ACRS THE REGION WITH PWAT VALUE OVER 2" ON 12Z
WAL SOUNDING (AND 1.75-2" AT GSO). 12Z NAM BRINGS PRECIP FARTHER
NORTH THAN PREVIOUS RUNS AND IT MAY BE ONTO SOMETHING AS IT IS
VERIFYING WELL THUS FAR. HAVE THUS INCREASED POPS TO 70% OVER MUCH
OF CENTRAL VA AS FAR N AS METRO RICHMOND THIS AFTN (WELCOME
RAINFALL HERE). SATELLITE TRENDS SUGGEST LITTLE CLEARING THIS
AFTN...WITH THE POSSIBLE EXCEPTION OF FAR SE VA/NE NC WHERE A
BRIEF PERIOD OF PARTIAL CLEARING MAY OVERSPREAD THE REGION OVER
THE NEXT FEW HRS BEFORE TSTMS REDEVELOP.
MAIN CONCERN TODAY WILL BE FOR HEAVY RAIN AND POSSIBLE FLASH
FLOODING HOWEVER SOME STRONG TO SEVERE STORMS WILL BE POSSIBLE IN
FAR SE VA/NE NC WHERE INSTABILITY IS A LITTLE HIGHER AND DUE TO
DEEP LAYER SHEAR 0-6 KM OF 30-35 KT. MAINLY A STRONG WIND THREAT
BUT AN ISOLATED VERY BRIEF WEAK TORNADO NOT OUT OF THE QUESTION
GIVEN THE LOW LEVEL BOUNDARY. IR SATELLITE SHOWS DEEP MOISTURE
PLUME FROM THE SW AND UPPER JET IS IN A FAVORABLE POSITION (RRQ
FORCING) TO SUPPORT LIKELY POPS MOST AREAS THIS AFTN AND TONIGHT.
IN ADDITION..SHOULD SEE TRAINING OF STORMS DUE TO LOW LEVEL SW JET
BEING NEARLY PARALLEL AND SIMILAR IN MAGNITUDE TO THE FLOW ALOFT
(LOW MBE VALUES). MUCH OF HAMPTON ROADS AND NE NC RECEIVED 2" OR
MORE OF RAINFALL OVER THE PAST 24 HRS AND MAY NEED TO CONSIDER A
FLASH FLOOD WATCH THIS AFTN THROUGH FRI MORNING IN THESE AREAS BUT
CONFIDENCE TOO LOW IN PLACEMENT OF HEAVIEST PRECIP (ESPECIALLY
GIVEN THE LATEST NAM KEEPING HEAVIER AMTS FARTHER INLAND/NW). WILL
CONTINUE MENTION OF LCLLY HEAVY RAINFALL THREAT IN HWO (AND SEVERE
THREAT OVER FAR SE VA/NE NC). LOWERED MAX TEMPS A FEW DEGREES WITH
HIGHS MAINLY IN THE LOWER-MID 80S.
S/W ENERGY TRACKS NE ALONG THE BNDRY TONIGHT. THIS WILL NOT ONLY
ENHANCE CONVECTION CHCS OVERNIGHT BUT SHOULD KEEP THE THREAT OF
PCPN GOING THROUGH THE NIGHT...PARTICULARLY ACRS SE VA/NE NC.
POPS WOULD LIKELY HAVE TO BE RAISED FURTHER WEST IF NAM VERIFIES.
LOWS M60S FAR NW TO LWR-MID 70S SE.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
SYSTEM LINGERS ALONG COASTAL AREAS FRIDAY MORNING BEFORE SLOWLY
EXITING OFF THE COAST DURING THE AFTN. DATA SHOWS PLENTY OF MSTR
ARND ALONG WITH SOME INSTABILITY TO INCLUDE CHC POPS THROUGH THE
DAY WITH THE HIGHEST POPS SERN AREAS. HIGHS GNRLY IN THE M80S. SCT
EVENING POPS FRI NIGHT...OTW BCMG PT CLDY. LOWS 65-70.
MODELS INDICATING THE FRONT WASHES OUT / DISSIPATES ACROSS THE AREA
SAT. KEPT A 20-30% POP OVER THE FAR NW AND IN SE VA/NE NC. PARTLY
SUNNY WITH HIGHS IN THE M-U80S.
QPF NXT 72 HRS AVGG 2/3RDS TO 1 IN ACROSS NWRN AREAS...1 TO 1.5
IN ACROSS CNTRL AREAS...1.5 TO 2.5 ACROSS SERN VA/NE NC.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AMPLIFIED UPPER FLOW OVER THE HIGHER LATITUDES WILL PUSH ANOTHER
ANOMALOUS TROUGH INTO THE NERN CONUS EARLY NEXT WEEK. THE RESULT
WILL BE BELOW NORMAL TEMPS AND WET CONDITIONS FROM THE UPPER MIDWEST
TO THE OH VALLEY. HOWEVER...THE LOCAL AREA REMAINS SEASONABLY WARM
AS MUCH OF THE COOLER AIR WILL BE LOCKED WEST OF THE CNTRL
APPALACHIANS.
FOR THE LATTER HALF OF THE WEEKEND...ONGOING RETURN FLOW ON THE
BACKSIDE OF HIGH PRESSURE ANCHORED OVER THE WRN ATLANTIC WILL RESULT
IN SLIGHTLY WARMER TEMPS AND DEWPOINTS SUN COMPARED TO SAT.
THICKNESSES YIELD TEMPS RIGHT AROUND 90 DEGS. A COLD FRONT WILL PUSH
INTO THE GREAT LAKES REGION SUN WITH SFC TROUGHING DEVELOPING OVER
THE LOCAL AREA. THETA-E ADVECTION AND A MOIST BL WILL RESULT IN
MLCAPE VALUES ~1500 J/KG. MODEL DERIVED PRECIP WATERS RANGE FROM
1.75 TO 2 INCHES. WHILE MOISTURE/INSTABILITY LOOK FAVORABLE...BEST
DYNAMICS/FORCING REMAINS WELL WEST OF THE AREA WITH THE BETTER
HEIGHT FALLS AND STRONGER WINDS ALOFT. SHEAR IS ALSO UNIMPRESSIVE
AND SOUNDINGS DEPICT SUBSIDENCE/WARM AIR ALOFT. WILL CARRY CHANCE
POPS IN THE NW...TAPERING OFF TO SILENT IN THE SE. BETTER COVERAGE
EXPECTED MON AS HEIGHT FALLS AND INCREASING WINDS ALOFT PROVIDE
BETTER FORCING FOR ASCENT AND COOLER MID-LEVEL TEMPS. COLD FRONT IS
EXPECTED TO REACH THE CNTRL APPALACHIANS LATE MON...SHARPENING THE
THERMAL TROUGH OVER THE LOCAL AREA. WARMER TEMPS AND DEWPOINTS WILL
PUSH MLCAPE VALUES HIGHER...BUT SHEAR REMAINS MARGINAL (AOB 20 KT).
THE RESULT WILL BE SCT AFTERNOON SHOWERS/THUNDERSTORMS ACROSS MUCH
OF THE REGION. COLD FRONT DROPS INTO THE REGION TUES-TUES NIGHT.
EXACT TIMING OF THE FRONT WILL IMPACT SENSIBLE WEATHER OVER THE
LOCAL AREA. WILL TREND TOWARD A BLEND BTWN THE MEDIUM RANGE
GUIDANCE...KEEPING THE BEST POPS ALONG THE COAST TUES. BASED ON THE
AIRMASS...WILL ALSO CARRY SLIGHT CHANCE POPS MON NIGHT-TUES MORNING
AS THE FRONT CROSS THE REGION. UPPER LOW BEGINS TO EJECT FROM THE
GREAT LAKES REGION TUES INTO SE CANADA...SLOWING THE FRONT AS IT
PUSHES OFFSHORE TUES NIGHT-WEDS MORNING. CONFIDENCE IS NOT HIGH
ATTM...BUT WILL HANG ON TO SLIGHT CHANCE POPS ALONG THE COAST WEDS
BASED ON THE FRONT LIKELY STALLING OFFSHORE.
TEMPS WILL REMAIN AROUND SEASONABLE NORMS...WARMING INTO THE UPPER
80S-LOW 90S THRU THE PERIOD. ANTICIPATE TUES TO BE THE WARMEST IN
ADVANCE OF THE FRONT...WITH HIGHS GENERALLY IN THE LOW 90S.
OVERNIGHT LOWS WILL GENERALLY BE IN THE UPPER 60S-LOW 70S...WITH MID
70S NEAR THE COAST.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
TSTMS CONTINUE TO DEVELOP ALONG THE ALBEMARLE SOUND. THIS IS ALONG
THE OUTFLOW FROM THE EARLIER CONVECTION. LOOKING AT THE HRRR THINK
THESE WILL FINALLY END BY AROUND 14Z. WILL HAVE A TEMPO GROUP AT
KECG AS THESE TSTMS COULD MOVE ACROSS THERE AT TIMES. UPPER TROF
CONTINUES ACROSS THE AREA TODAY. THERE WILL BE SEVERAL BOUNDARIES
ACROSS THE AREA WHICH COULD FOCUS CONVECTION THIS AFTERNOON INTO
TONIGHT. ALL MODELS AGREE ON CONVECTION DEVELOPING JUST NOT SURE
WHETHER TO THE WEST MOSTLY RECEIVES IT OR BACK ACROSS THE
SOUTHEAST. MOST HI RES MODELS ARE LEANING TOWARD SE VA AND NE NC
SO WILL PUT A TEMPO GROUP IN THAT AREA THIS AFTERNOON. HOWEVER
THINK MOST AREAS WILL GO TO MVFR OR EVEN IFR IN TSTMS SOMETIME
THIS AFTERNOON OR TONIGHT. WITH DIMINISHING FLOW BY TONIGHT ANY
THUNDERSTORMS THAT DO FORM WILL BE SLOW TO MOVE. OUTSIDE OF THE
PRECIPITATION EXPECT VFR CONDITIONS WITH SOME CLOUDS AROUND 10
THOUSAND FEET.
FRONT CROSSES AREA BY FRIDAY...LEAVING FRI NGT/SAT DRY ATTM. NEXT
FRONT COULD BRING THE POTENTIAL FOR MORE SHWRS/TSTMS TO THE REGION
LATE SUNDAY OR MONDAY.
&&
.MARINE...
SUB-SCA CONDITIONS ARE EXPECTED OVER THE WATERS THROUGH THE WEEK. A
WEAK TROF IS TO THE WEST OF THE WATERS KEEPING MAINLY A LIGHT
SOUTHERLY WIND OVER THE WATERS. A WEAK LOW PRESSURE SYSTEM WILL MOVE
ALONG THIS BOUNDARY TONIGHT AND FRIDAY. THIS WILL ALLOW THE WINDS TO
BE MORE SOUTHEAST AT TIMES. AFTER THE LOW MOVES PAST FRIDAY NIGHT
THE TROF WILL MOVE OFF THE COAST SATURDAY. WILL HAVE LIKELY
THUNDERSTORMS THIS AFTERNOON AND TONIGHT OVER THE SOUTHERN WATERS
WITH A CHANCE ACROSS THE NORTHERN WATERS.SCATTERED SHOWERS AND
THUNDERSTORMS WILL CONTINUE ACROSS THE WATERS FRIDAY INTO FRIDAY
NIGHT. WINDS WILL BECOME MORE WEST TO NORTH OVER THE WEEKEND. FLOW
VEERS TO THE SOUTH SUN...REMAINING SUB SCA AT 10-15 KT. SEAS REMAIN
2-3 FT. LOW PRESSURE LIFTS INTO THE GREAT LAKES REGION MON AS A COLD
FRONT PUSHES INTO THE OH VALLEY. GRADIENT WILL STRENGTHEN SLIGHTLY
OVER THE WATERS SUN NIGHT-MON...BUT REMAINS SUB-SCA. PERSISTENT SLY
FLOW WILL PUSH SEAS TO 4 FT IN THE NRN WATERS...BUT ANTICIPATE SEAS
TO REMAIN UNDER 5 FT. COLD FRONT CROSSES THE WATERS TUES NIGHT-WED
MORNING.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LKB
NEAR TERM...LKB
SHORT TERM...LKB/MPR
LONG TERM...SAM
AVIATION...JAB
MARINE...JAB
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1140 AM EDT THU JUL 10 2014
.SYNOPSIS...
A FRONTAL BOUNDARY STALLS OVER THE REGION TODAY THROUGH FRIDAY.
A WEAK AREA OF LOW PRESSURE MOVES NORTHEAST ALONG THIS BOUNDARY
TONIGHT THEN PUSHES OFFSHORE FRIDAY. HIGH PRESSURE BUILDS SOUTH
ACROSS THE MID ATLANTIC REGION THIS WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
LATEST ANALYSIS SHOWING FRONTAL BOUNDARY STALLED OVER WRN PORTIONS
OF THE CWA WITH AN AREA OF SHOWERS/EMBEDDED TSTMS DEVELOPING ALONG
THE FRONT ACRS MECKLENBURG/LUNENBURG AS OF 11 AM. VERY MOIST
AIRMASS IN PLACE ACRS THE REGION WITH PWAT VALUE OVER 2" ON 12Z
WAL SOUNDING (AND 1.75-2" AT GSO). 12Z NAM BRINGS PRECIP FARTHER
NORTH THAN PREVIOUS RUNS AND IT MAY BE ONTO SOMETHING AS IT IS
VERIFYING WELL THUS FAR. HAVE THUS INCREASED POPS TO 70% OVER MUCH
OF CENTRAL VA AS FAR N AS METRO RICHMOND THIS AFTN (WELCOME
RAINFALL HERE). SATELLITE TRENDS SUGGEST LITTLE CLEARING THIS
AFTN...WITH THE POSSIBLE EXCEPTION OF FAR SE VA/NE NC WHERE A
BRIEF PERIOD OF PARTIAL CLEARING MAY OVERSPREAD THE REGION OVER
THE NEXT FEW HRS BEFORE TSTMS REDEVELOP.
MAIN CONCERN TODAY WILL BE FOR HEAVY RAIN AND POSSIBLE FLASH
FLOODING. IR SATELLITE SHOWS DEEP MOISTURE PLUME FROM THE SW AND
UPPER JET IS IN A FAVORABLE POSITION (RRQ FORCING) TO SUPPORT
LIKELY POPS MOST AREAS THIS AFTN AND TONIGHT. IN ADDITION..SHOULD
SEE TRAINING OF STORMS DUE TO LOW LEVEL SW JET BEING NEARLY
PARALLEL AND SIMILAR IN MAGNITUDE TO THE FLOW ALOFT (LOW MBE
VALUES). MUCH OF HAMPTON ROADS AND NE NC RECEIVED 2" OR MORE OF
RAINFALL OVER THE PAST 24 HRS AND MAY NEED TO CONSIDER A FLASH
FLOOD WATCH THIS AFTN THROUGH FRI MORNING IN THESE AREAS BUT
CONFIDENCE TOO LOW IN PLACEMENT OF HEAVIEST PRECIP (ESPECIALLY
GIVEN THE LATEST NAM KEEPING HEAVIER AMTS FARTHER INLAND/NW). WILL
CONTINUE MENTION OF LCLLY HEAVY RAINFALL THREAT IN HWO. LOWERED
MAX TEMPS A FEW DEGREES WITH HIGHS MAINLY IN THE LOWER-MID 80S.
S/W ENERGY TRACKS NE ALONG THE BNDRY TONIGHT. THIS WILL NOT ONLY
ENHANCE CONVECTION CHCS OVERNIGHT BUT SHOULD KEEP THE THREAT OF
PCPN GOING THROUGH THE NIGHT...PARTICULARLY ACRS SE VA/NE NC.
POPS WOULD LIKELY HAVE TO BE RAISED FURTHER WEST IF NAM VERIFIES.
LOWS M60S FAR NW TO LWR-MID 70S SE.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
SYSTEM LINGERS ALONG COASTAL AREAS FRIDAY MORNING BEFORE SLOWLY
EXITING OFF THE COAST DURING THE AFTN. DATA SHOWS PLENTY OF MSTR
ARND ALONG WITH SOME INSTABILITY TO INCLUDE CHC POPS THROUGH THE
DAY WITH THE HIGHEST POPS SERN AREAS. HIGHS GNRLY IN THE M80S. SCT
EVENING POPS FRI NIGHT...OTW BCMG PT CLDY. LOWS 65-70.
MODELS INDICATING THE FRONT WASHES OUT / DISSIPATES ACROSS THE AREA
SAT. KEPT A 20-30% POP OVER THE FAR NW AND IN SE VA/NE NC. PARTLY
SUNNY WITH HIGHS IN THE M-U80S.
QPF NXT 72 HRS AVGG 2/3RDS TO 1 IN ACROSS NWRN AREAS...1 TO 1.5
IN ACROSS CNTRL AREAS...1.5 TO 2.5 ACROSS SERN VA/NE NC.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AMPLIFIED UPPER FLOW OVER THE HIGHER LATITUDES WILL PUSH ANOTHER
ANOMALOUS TROUGH INTO THE NERN CONUS EARLY NEXT WEEK. THE RESULT
WILL BE BELOW NORMAL TEMPS AND WET CONDITIONS FROM THE UPPER MIDWEST
TO THE OH VALLEY. HOWEVER...THE LOCAL AREA REMAINS SEASONABLY WARM
AS MUCH OF THE COOLER AIR WILL BE LOCKED WEST OF THE CNTRL
APPALACHIANS.
FOR THE LATTER HALF OF THE WEEKEND...ONGOING RETURN FLOW ON THE
BACKSIDE OF HIGH PRESSURE ANCHORED OVER THE WRN ATLANTIC WILL RESULT
IN SLIGHTLY WARMER TEMPS AND DEWPOINTS SUN COMPARED TO SAT.
THICKNESSES YIELD TEMPS RIGHT AROUND 90 DEGS. A COLD FRONT WILL PUSH
INTO THE GREAT LAKES REGION SUN WITH SFC TROUGHING DEVELOPING OVER
THE LOCAL AREA. THETA-E ADVECTION AND A MOIST BL WILL RESULT IN
MLCAPE VALUES ~1500 J/KG. MODEL DERIVED PRECIP WATERS RANGE FROM
1.75 TO 2 INCHES. WHILE MOISTURE/INSTABILITY LOOK FAVORABLE...BEST
DYNAMICS/FORCING REMAINS WELL WEST OF THE AREA WITH THE BETTER
HEIGHT FALLS AND STRONGER WINDS ALOFT. SHEAR IS ALSO UNIMPRESSIVE
AND SOUNDINGS DEPICT SUBSIDENCE/WARM AIR ALOFT. WILL CARRY CHANCE
POPS IN THE NW...TAPERING OFF TO SILENT IN THE SE. BETTER COVERAGE
EXPECTED MON AS HEIGHT FALLS AND INCREASING WINDS ALOFT PROVIDE
BETTER FORCING FOR ASCENT AND COOLER MID-LEVEL TEMPS. COLD FRONT IS
EXPECTED TO REACH THE CNTRL APPALACHIANS LATE MON...SHARPENING THE
THERMAL TROUGH OVER THE LOCAL AREA. WARMER TEMPS AND DEWPOINTS WILL
PUSH MLCAPE VALUES HIGHER...BUT SHEAR REMAINS MARGINAL (AOB 20 KT).
THE RESULT WILL BE SCT AFTERNOON SHOWERS/THUNDERSTORMS ACROSS MUCH
OF THE REGION. COLD FRONT DROPS INTO THE REGION TUES-TUES NIGHT.
EXACT TIMING OF THE FRONT WILL IMPACT SENSIBLE WEATHER OVER THE
LOCAL AREA. WILL TREND TOWARD A BLEND BTWN THE MEDIUM RANGE
GUIDANCE...KEEPING THE BEST POPS ALONG THE COAST TUES. BASED ON THE
AIRMASS...WILL ALSO CARRY SLIGHT CHANCE POPS MON NIGHT-TUES MORNING
AS THE FRONT CROSS THE REGION. UPPER LOW BEGINS TO EJECT FROM THE
GREAT LAKES REGION TUES INTO SE CANADA...SLOWING THE FRONT AS IT
PUSHES OFFSHORE TUES NIGHT-WEDS MORNING. CONFIDENCE IS NOT HIGH
ATTM...BUT WILL HANG ON TO SLIGHT CHANCE POPS ALONG THE COAST WEDS
BASED ON THE FRONT LIKELY STALLING OFFSHORE.
TEMPS WILL REMAIN AROUND SEASONABLE NORMS...WARMING INTO THE UPPER
80S-LOW 90S THRU THE PERIOD. ANTICIPATE TUES TO BE THE WARMEST IN
ADVANCE OF THE FRONT...WITH HIGHS GENERALLY IN THE LOW 90S.
OVERNIGHT LOWS WILL GENERALLY BE IN THE UPPER 60S-LOW 70S...WITH MID
70S NEAR THE COAST.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
TSTMS CONTINUE TO DEVELOP ALONG THE ALBEMARLE SOUND. THIS IS ALONG
THE OUTFLOW FROM THE EARLIER CONVECTION. LOOKING AT THE HRRR THINK
THESE WILL FINALLY END BY AROUND 14Z. WILL HAVE A TEMPO GROUP AT
KECG AS THESE TSTMS COULD MOVE ACROSS THERE AT TIMES. UPPER TROF
CONTINUES ACROSS THE AREA TODAY. THERE WILL BE SEVERAL BOUNDARIES
ACROSS THE AREA WHICH COULD FOCUS CONVECTION THIS AFTERNOON INTO
TONIGHT. ALL MODELS AGREE ON CONVECTION DEVELOPING JUST NOT SURE
WHETHER TO THE WEST MOSTLY RECEIVES IT OR BACK ACROSS THE
SOUTHEAST. MOST HI RES MODELS ARE LEANING TOWARD SE VA AND NE NC
SO WILL PUT A TEMPO GROUP IN THAT AREA THIS AFTERNOON. HOWEVER
THINK MOST AREAS WILL GO TO MVFR OR EVEN IFR IN TSTMS SOMETIME
THIS AFTERNOON OR TONIGHT. WITH DIMINISHING FLOW BY TONIGHT ANY
THUNDERSTORMS THAT DO FORM WILL BE SLOW TO MOVE. OUTSIDE OF THE
PRECIPITATION EXPECT VFR CONDITIONS WITH SOME CLOUDS AROUND 10
THOUSAND FEET.
FRONT CROSSES AREA BY FRIDAY...LEAVING FRI NGT/SAT DRY ATTM. NEXT
FRONT COULD BRING THE POTENTIAL FOR MORE SHWRS/TSTMS TO THE REGION
LATE SUNDAY OR MONDAY.
&&
.MARINE...
SUB-SCA CONDITIONS ARE EXPECTED OVER THE WATERS THROUGH THE WEEK. A
WEAK TROF IS TO THE WEST OF THE WATERS KEEPING MAINLY A LIGHT
SOUTHERLY WIND OVER THE WATERS. A WEAK LOW PRESSURE SYSTEM WILL MOVE
ALONG THIS BOUNDARY TONIGHT AND FRIDAY. THIS WILL ALLOW THE WINDS TO
BE MORE SOUTHEAST AT TIMES. AFTER THE LOW MOVES PAST FRIDAY NIGHT
THE TROF WILL MOVE OFF THE COAST SATURDAY. WILL HAVE LIKELY
THUNDERSTORMS THIS AFTERNOON AND TONIGHT OVER THE SOUTHERN WATERS
WITH A CHANCE ACROSS THE NORTHERN WATERS.SCATTERED SHOWERS AND
THUNDERSTORMS WILL CONTINUE ACROSS THE WATERS FRIDAY INTO FRIDAY
NIGHT. WINDS WILL BECOME MORE WEST TO NORTH OVER THE WEEKEND. FLOW
VEERS TO THE SOUTH SUN...REMAINING SUB SCA AT 10-15 KT. SEAS REMAIN
2-3 FT. LOW PRESSURE LIFTS INTO THE GREAT LAKES REGION MON AS A COLD
FRONT PUSHES INTO THE OH VALLEY. GRADIENT WILL STRENGTHEN SLIGHTLY
OVER THE WATERS SUN NIGHT-MON...BUT REMAINS SUB-SCA. PERSISTENT SLY
FLOW WILL PUSH SEAS TO 4 FT IN THE NRN WATERS...BUT ANTICIPATE SEAS
TO REMAIN UNDER 5 FT. COLD FRONT CROSSES THE WATERS TUES NIGHT-WED
MORNING.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LKB
NEAR TERM...LKB
SHORT TERM...LKB/MPR
LONG TERM...SAM
AVIATION...JAB
MARINE...JAB
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
650 AM EDT THU JUL 10 2014
.SYNOPSIS...
A FRONTAL BOUNDARY STALLS OVER THE REGION TODAY THROUGH FRIDAY.
A WEAK AREA OF LOW PRESSURE MOVES NORTHEAST ALONG THIS BOUNDARY
TONIGHT THEN PUSHES OFFSHORE FRIDAY. HIGH PRESSURE BUILDS SOUTH
ACROSS THE MID ATLANTIC REGION THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST MSAS SHOWING FRONTAL BNDRY NOW STALLED ACROSS THE FA WITH A
WEAK SFC TROF ALONG THE COAST. LATEST RADAR SHOWING SHWRS/TSTRMS
CONTG TO DVLP ALONG THE COAST WITH SCNDRY BATCH OF LIGHTER PCPN
APPRCHG WRN CNTYS FROM THE WEST. ADJUSTED MORNING GRIDS A BIT MORE
TOWARD THESE CURRENT CNDTNS.
PVS DSCN:
MODELS AGREE THE FRONT STALLS ACROSS SERN PORTIONS OF FA LATER
TODAY DUE TO A FLATTENING WSW FLOW ALOFT BCMG PARALLEL TO THE
BOUNDARY. WHERE THE MODELS DIFFER IS WHAT THIS BOUNDARY DOES ONCE
A WEAK S/W APPROACHES FROM THE SW BY THIS EVENING. NAM MOST
AGGRESSIVE IN RETROGRADING THE BOUNDARY TO NEAR THE I95 CORRIDOR
FOCUSING THE CONVECTION THERE. GFS/SREF HAVE IT MEANDERING AROUND
THE COASTAL PLAIN AREAS...FOCUSING CONVECTION ACROSS SERN AREAS.
TOSSED AROUND THE IDEA OF A FF WATCH FOR SERN VA/NE NC LATER TODAY
AND TONIGHT GIVEN DUAL POLE ESTIMATES OF 2 TO 3.5 IN (WHICH HAS
VERIFIED BY GROUND REPORTS) AND AN ADDITIONAL 1.5 TO 2.5 IN OF QPF.
HOWEVER...MY CONFIDENCE LOWERED AFTER SEEING THE 00Z GUIDANCE WHERE
THE NAM PUSHES AXIS OF HEAVIEST RAINFALL WEST OF WHERE ANY WATCH
WOULD BE GIVEN THE RECENT RAINFALL AND WHERE IT HAS BEEN RATHER
DRY OF LATE (I95 CORRIDOR) WHILE THE GFS ACTUALLY HAS THE HEAVIEST
RAINFALL AFTER 00Z TONIGHT. DECIDED TO HOLD OFF AN ANY FF WATCH
ATTM (FF GUID FOR THOSE AREAS AOA 2 IN PER HR)...BUT MENTIONED
THE LCLLY HEAVY RAINFALL THREAT IN HWO. LEANED TOWARD A SREF TIMING
SOLN WITH THIS PACKAGE WHICH SEEMS TO BE A COMPROMISE BTWN THE MODELS.
GIVEN THE ABOVE SCENARIO...HAVE EXPANDED THE LIKELY POPS A BIT FURTHER
NORTH THIS AFTRN BUT KEPT CHC POPS ACROSS NORTHERN HALF OF FA. ALSO
KEPT THE CHC POPS ACROSS WRN HALF OF FA THIS MORNING GIVEN BATCH OF
PCPN MOVG NE FROM WRN NC. HIGHS M-U80S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
S/W ENERGY TRACKS NE ALONG THE BNDRY TONIGHT. THIS WILL NOT ONLY
ENHANCE CONVECTION CHCS THIS EVENING BUT SHOULD KEEP THE THREAT OF
PCPN GOING THROUGH THE NIGHT. HIGHEST POPS ACROSS SERN AREAS GIVEN A
SREF SOLN. POPS WOULD LIKELY HAVE TO BE RAISED FURTHER WEST IF NAM
VERIFIES. LOWS M60S-L70S.
SYSTEM LINGERS ALONG COASTAL AREAS FRIDAY MORNING BEFORE SLOWLY
EXITING OFF THE COAST DURING THE AFTRN. DATA SHOWS PLNTY OF MSTR
ARND ALONG WITH SOME INSTABILITY TO INCLUDE CHC POPS THROUGH THE
DAY WITH THE HIGHEST POPS SERN AREAS. HIGHS GNRLY IN THE M80S.
SCT EVENING POPS FRI NIGHT...OTW BCMG PT CLDY. LOWS 65-70.
MODELS INDICATING THE FRONT WASHES OUT / DISSIPATES ACROSS THE AREA
SAT. KEPT A 20-30% POP OVER THE FAR NW AND IN SE VA/NE NC. PARTLY
SUNNY WITH HIGHS IN THE M-U80S.
QPF NXT 72 HRS AVGG 2/3RDS TO 1 IN ACROSS NWRN AREAS...1 TO 1.5
IN ACROSS CNTRL AREAS...1.5 TO 2.5 ACROSS SERN VA/NE NC.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AMPLIFIED UPPER FLOW OVER THE HIGHER LATITUDES WILL PUSH ANOTHER
ANOMALOUS TROUGH INTO THE NERN CONUS EARLY NEXT WEEK. THE RESULT
WILL BE BELOW NORMAL TEMPS AND WET CONDITIONS FROM THE UPPER MIDWEST
TO THE OH VALLEY. HOWEVER...THE LOCAL AREA REMAINS SEASONABLY WARM
AS MUCH OF THE COOLER AIR WILL BE LOCKED WEST OF THE CNTRL
APPALACHIANS.
FOR THE LATTER HALF OF THE WEEKEND...ONGOING RETURN FLOW ON THE
BACKSIDE OF HIGH PRESSURE ANCHORED OVER THE WRN ATLANTIC WILL RESULT
IN SLIGHTLY WARMER TEMPS AND DEWPOINTS SUN COMPARED TO SAT.
THICKNESSES YIELD TEMPS RIGHT AROUND 90 DEGS. A COLD FRONT WILL PUSH
INTO THE GREAT LAKES REGION SUN WITH SFC TROUGHING DEVELOPING OVER
THE LOCAL AREA. THETA-E ADVECTION AND A MOIST BL WILL RESULT IN
MLCAPE VALUES ~1500 J/KG. MODEL DERIVED PRECIP WATERS RANGE FROM
1.75 TO 2 INCHES. WHILE MOISTURE/INSTABILITY LOOK FAVORABLE...BEST
DYNAMICS/FORCING REMAINS WELL WEST OF THE AREA WITH THE BETTER
HEIGHT FALLS AND STRONGER WINDS ALOFT. SHEAR IS ALSO UNIMPRESSIVE
AND SOUNDINGS DEPICT SUBSIDENCE/WARM AIR ALOFT. WILL CARRY CHANCE
POPS IN THE NW...TAPERING OFF TO SILENT IN THE SE. BETTER COVERAGE
EXPECTED MON AS HEIGHT FALLS AND INCREASING WINDS ALOFT PROVIDE
BETTER FORCING FOR ASCENT AND COOLER MID-LEVEL TEMPS. COLD FRONT IS
EXPECTED TO REACH THE CNTRL APPALACHIANS LATE MON...SHARPENING THE
THERMAL TROUGH OVER THE LOCAL AREA. WARMER TEMPS AND DEWPOINTS WILL
PUSH MLCAPE VALUES HIGHER...BUT SHEAR REMAINS MARGINAL (AOB 20 KT).
THE RESULT WILL BE SCT AFTERNOON SHOWERS/THUNDERSTORMS ACROSS MUCH
OF THE REGION. COLD FRONT DROPS INTO THE REGION TUES-TUES NIGHT.
EXACT TIMING OF THE FRONT WILL IMPACT SENSIBLE WEATHER OVER THE
LOCAL AREA. WILL TREND TOWARD A BLEND BTWN THE MEDIUM RANGE
GUIDANCE...KEEPING THE BEST POPS ALONG THE COAST TUES. BASED ON THE
AIRMASS...WILL ALSO CARRY SLIGHT CHANCE POPS MON NIGHT-TUES MORNING
AS THE FRONT CROSS THE REGION. UPPER LOW BEGINS TO EJECT FROM THE
GREAT LAKES REGION TUES INTO SE CANADA...SLOWING THE FRONT AS IT
PUSHES OFFSHORE TUES NIGHT-WEDS MORNING. CONFIDENCE IS NOT HIGH
ATTM...BUT WILL HANG ON TO SLIGHT CHANCE POPS ALONG THE COAST WEDS
BASED ON THE FRONT LIKELY STALLING OFFSHORE.
TEMPS WILL REMAIN AROUND SEASONABLE NORMS...WARMING INTO THE UPPER
80S-LOW 90S THRU THE PERIOD. ANTICIPATE TUES TO BE THE WARMEST IN
ADVANCE OF THE FRONT...WITH HIGHS GENERALLY IN THE LOW 90S.
OVERNIGHT LOWS WILL GENERALLY BE IN THE UPPER 60S-LOW 70S...WITH MID
70S NEAR THE COAST.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
TSTMS CONTINUE TO DEVELOP ALONG THE ALBEMARLE SOUND. THIS IS ALONG
THE OUTFLOW FROM THE EARLIER CONVECTION. LOOKING AT THE HRRR THINK
THESE WILL FINALLY END BY AROUND 14Z. WILL HAVE A TEMPO GROUP AT
KECG AS THESE TSTMS COULD MOVE ACROSS THERE AT TIMES. UPPER TROF
CONTINUES ACROSS THE AREA TODAY. THERE WILL BE SEVERAL BOUNDARIES
ACROSS THE AREA WHICH COULD FOCUS CONVECTION THIS AFTERNOON INTO
TONIGHT. ALL MODELS AGREE ON CONVECTION DEVELOPING JUST NOT SURE
WHETHER TO THE WEST MOSTLY RECEIVES IT OR BACK ACROSS THE
SOUTHEAST. MOST HI RES MODELS ARE LEANING TOWARD SE VA AND NE NC
SO WILL PUT A TEMPO GROUP IN THAT AREA THIS AFTERNOON. HOWEVER
THINK MOST AREAS WILL GO TO MVFR OR EVEN IFR IN TSTMS SOMETIME
THIS AFTERNOON OR TONIGHT. WITH DIMINISHING FLOW BY TONIGHT ANY
THUNDERSTORMS THAT DO FORM WILL BE SLOW TO MOVE. OUTSIDE OF THE
PRECIPITATION EXPECT VFR CONDITIONS WITH SOME CLOUDS AROUND 10
THOUSAND FEET.
FRONT CROSSES AREA BY FRIDAY...LEAVING FRI NGT/SAT DRY ATTM. NEXT
FRONT COULD BRING THE POTENTIAL FOR MORE SHWRS/TSTMS TO THE REGION
LATE SUNDAY OR MONDAY.
&&
.MARINE...
SUB-SCA CONDITIONS ARE EXPECTED OVER THE WATERS THROUGH THE WEEK. A
WEAK TROF IS TO THE WEST OF THE WATERS KEEPING MAINLY A LIGHT
SOUTHERLY WIND OVER THE WATERS. A WEAK LOW PRESSURE SYSTEM WILL MOVE
ALONG THIS BOUNDARY TONIGHT AND FRIDAY. THIS WILL ALLOW THE WINDS TO
BE MORE SOUTHEAST AT TIMES. AFTER THE LOW MOVES PAST FRIDAY NIGHT
THE TROF WILL MOVE OFF THE COAST SATURDAY. WILL HAVE LIKELY
THUNDERSTORMS THIS AFTERNOON AND TONIGHT OVER THE SOUTHERN WATERS
WITH A CHANCE ACROSS THE NORTHERN WATERS.SCATTERED SHOWERS AND
THUNDERSTORMS WILL CONTINUE ACROSS THE WATERS FRIDAY INTO FRIDAY
NIGHT. WINDS WILL BECOME MORE WEST TO NORTH OVER THE WEEKEND. FLOW
VEERS TO THE SOUTH SUN...REMAINING SUB SCA AT 10-15 KT. SEAS REMAIN
2-3 FT. LOW PRESSURE LIFTS INTO THE GREAT LAKES REGION MON AS A COLD
FRONT PUSHES INTO THE OH VALLEY. GRADIENT WILL STRENGTHEN SLIGHTLY
OVER THE WATERS SUN NIGHT-MON...BUT REMAINS SUB-SCA. PERSISTENT SLY
FLOW WILL PUSH SEAS TO 4 FT IN THE NRN WATERS...BUT ANTICIPATE SEAS
TO REMAIN UNDER 5 FT. COLD FRONT CROSSES THE WATERS TUES NIGHT-WED
MORNING.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MPR
NEAR TERM...MPR
SHORT TERM...MPR
LONG TERM...SAM
AVIATION...JAB
MARINE...JAB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
753 PM EDT FRI JUL 11 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 429 PM EDT FRI JUL 11 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A ZONAL PATTERN THROUGH THE
NRN CONUS BETWEEN A TROUGH OVER CNTRL CANADA AND A RIDGE OVER THE
SRN PLAINS. A WEAK SHORTWAVE TROUGH OVER LAKE SUPERIOR INTO CNTRL
UPPER MI HELPED PRODUCE SOME LIGHT SHOWERS ACROSS THE CWA TODAY.
SCT/ISOLD SHRA/TSRA FROM NEAR KINL INTO N CNTRL MN HAD DEVELOPED
ALONG A COLD FRONT/TROUGH AHEAD OF ANOTHER WEAK SHRTWV MOVING
THROUGH NORTH DAKOTA. MOSTLY CLOUDY SKIES OVER UPPER MI HAD LIMITED
TEMPS TO THE LOWER TO MID 70S AND LIMITED MLCAPE VALUES TO LESS THAN
400 J/KG.
TONIGHT...EXPECT THAT SHRA/TSRA OVER NRN MN WILL EXPAND IN COVERAGE
AND MOVE TOWARD UPPER MI. HOWEVER...WITH ONLY MARGINAL INSTABILITY
FCST OVER THE AREA...MUCAPE INTO THE 400-800 J/KG RANGE...THE
CONVECTION SHOULD WEAKEN WITH ONLY ISOLD TSRA. SCT SHRA COVERAGE
WITH CHANCE POPS WAS MENTIONED GIVEN THE WEAK FORCING ASSOCIATED
WITH THE FRONT AND SHRTWV SLIDING THROUGH THE NRN GREAT LAKES. THE
REMAINING SHOWERS ARE EXPECTED TO MOVE INTO THE ERN CWA LATE THIS
EVENING AND DIMINISH FROM WEST TO EAST OVERNIGHT.
SATURDAY...THE WEAKENING COLD FRONT THROUGH UPPER MI WILL PROVIDE A
BOUNDARY/FOCUS FOR POTENTIAL SHRA/TSRA DEVELOPMENT...ESPECIALLY WITH
ONSET OF STRONGER DAYTIME HEATING. EXPECT THE GREATEST PCPN COVERAGE
OVER THE SOUTH AND THROUGH ERN UPPER MI WHERE THE HIGHER RES MODELS
SUGGEST THE LOW LEVEL CONV WILL BE STRONGEST. MLCAPE VALUES TO NEAR
1K J/KG...PER GEM-REGIONAL AND GFS COMBINED WITH 0-6KM SHEAR VALUES
OF 35-40 KNOTS COULD SUPPORT SOME STRONG AND POSSIBLY SEVERE STORMS
IF CLOUD DEPENDENT INSTABILITY IS REALIZED. THE MODELS HAVE ALSO SHOWN A
CONSISTENT SIGNAL THAT SHRA/TSRA WILL MOVE INTO WI ASSOCIATED WITH
STRONGER SHORTWAVE TROUGH. THERE IS STILL TIMING/POSITION UNCERTAINTY
ON HOW IT WOULD AFFECT MAINLY SRN UPPER MI BY LATE AFTERNOON.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 431 PM EDT FRI JUL 11 2014
THE MAIN STORY IN THE LONG TERM CONTINUES TO BE THE SEPTEMBER-LIKE
CONDITIONS EXPECTED ACROSS THE UPPER GREAT LAKES EARLY NEXT WEEK.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...A DEEP MID-LEVEL LOW OVER FAR
SOUTHWEST HUDSON BAY WILL CONTINUE ITS TREK SOUTHWARD AT THE
BEGINNING OF THE PERIOD. CONVECTIVE POTENTIAL ACROSS THE SOUTHEAST
HALF FOR SATURDAY NIGHT WILL DEPEND HEAVILY ON BOTH THE AMOUNT OF
DIURNAL HEATING SATURDAY AND THE LOCATION OF THE DECAYING LOW-LEVEL
CONVERGENCE ZONE. WHILE MCS ACTIVITY LOOKS TO BE MOST PRONOUNCED
ALONG THE NOSE OF A DEVELOPING LOW-LEVEL JET ACROSS WI SATURDAY
AFTERNOON AND EVENING...RESIDUAL 305-315K ISENTROPIC LIFT NORTH OF
THE LOW-LEVEL BOUNDARY MAY BE ENOUGH TO TAP INTO REMAINING MUCAPE OF
AROUND 500 J/KG AS NOTED BY BOTH THE 12Z NAM AND 12Z GEM. ANY
THUNDER ACTIVITY SHOULD REMAIN WEAK THIS FAR NORTH GIVEN A STABLE
SFC LAYER AND OVERALL LIMITED INSTABILITY. HOWEVER...A FEW STRONGER
GUSTS CANNOT BE RULED OUT IN THE EARLY EVENING HOURS FAR SOUTH
CENTRAL WITH ANY STORM ROOTED ALONG THE SFC CONVERGENCE ZONE.
A MID-LEVEL TROUGH AXIS ASSOCIATED WITH THE DEEP LOW WILL CROSS THE
CWA FROM WEST TO EAST LATE SATURDAY NIGHT INTO SUNDAY. WITH LITTLE
ADDITIONAL SUPPORT AND GENERALLY DRY CONDITIONS...ONLY SOME ISOLATED
SHOWER ACTIVITY IS EXPECTED. AFTER THE TROUGH PASSAGE ON
SUNDAY...SKIES LOOK TO BECOME MOSTLY CLEAR FOR A 12-18 HOUR WINDOW.
THIS WILL ALLOW FOR INCREASED MIXING ACROSS THE WEST...WITH WESTERLY
GUSTS TO 25 MPH ACROSS THE KEWEENAW.
MONDAY AND TUESDAY...BY MONDAY MORNING...THE MID-LEVEL LOW WILL
SPLIT INTO TWO WAVES OVER ONTARIO. THE EASTERN SEGMENT OVER
SOUTHERN JAMES BAY WILL EJECT NORTHEASTWARD ACROSS QUEBEC THROUGH
MONDAY. MEANWHILE...THE WESTERN SEGMENT WILL BE TRACKING
SOUTHEASTWARD ACROSS THE BOUNDARY WATERS OF MN AROUND 12Z MONDAY.
THIS WESTERN EXTENSION WILL BECOME STACKED UPWARD FROM H7...SO
PROGRESSION OF THE SYSTEM WILL BE QUITE SLOW. THE MID/UPPER-LOW IS
PROGGED TO TRACK FROM NEAR DLH MONDAY AFTERNOON TO NEAR GRB BY
TUESDAY AFTERNOON. GIVEN THE OVERALL DYNAMICS OF THE SYSTEM...THE
ENTIRE AREA SHOULD SEE AT LEAST SOME SHOWERS DURING THE DAY. ONE
LIMITING FACTOR TO COVERAGE IS A PRESENCE OF DEEP MOISTURE. SOMEWHAT
DRY AIR ABOVE H5 SHOULD KEEP SHOWERS LESS WIDESPREAD AWAY FROM THE
LOW CENTER. SOME DIURNAL HEATING ASSISTANCE WILL ALSO ALLOW FOR
GREATER COVERAGE AWAY FROM THE GREAT LAKES. THEREFORE...THE BEST
COVERAGE IS EXPECTED ALONG THE WI BORDER...WHERE LIKELY POPS HAVE
BEEN INTRODUCED.
TEMPS WILL BE QUITE COOL FOR MID-JULY...WITH H8 TEMPS AT OR BELOW
5C. WITH CLOUDY AND SHOWERS AROUND...HIGHS WILL STRUGGLE TO GET OUT
OF THE 50S ACROSS MUCH OF THE CWA BOTH MONDAY AND TUESDAY. SOME
LOCALES ALONG LAKE SUPERIOR MAY EVEN FAIL TO REACH 50. THESE NUMBERS
ARE 25 DEGREES BELOW AVERAGE...AND WILL LIKELY SET RECORD LOW
MAXIMUM TEMPS ACROSS THE AREA.
SHOWERY ACTIVITY WILL CONTINUE INTO TUESDAY WITH THE PASSAGE OF A
DEFORMATION/FGEN REGION ON THE BACKSIDE OF THE MID/UPPER LOW. THESE
SHOWERS WILL BE SLOW TO MOVE EASTWARD AS THE LOW ONLY REACHES
NORTHERN LAKE HURON BY LATE TUESDAY NIGHT.
WEDNESDAY THROUGH FRIDAY...THE GFS ADVERTISES A MUCH QUICKER
DEPARTURE OF THE MID-LEVEL LOW THAN THE ECMWF/GEM. THIS HAS
IMPLICATIONS ON THE AMOUNT OF MOISTURE AVAILABLE FOR CONTINUED CLOUD
COVER AND HIGH TEMPS ACROSS THE AREA. OTHERWISE...THE STOUT RIDGE
ACROSS THE WESTERN STATES AND PROVINCES THAT DEVELOPED IN RESPONSE
TO THE DEEP EASTERN TROUGH WILL BEGIN TO SHIFT ACROSS THE NORTHERN
PLAINS ON THURSDAY AND THE UPPER GREAT LAKES ON FRIDAY. THIS SHOULD
BRING AN OVERALL QUIET PERIOD OF WEATHER WITH A GRADUAL WARMING
TREND INTO THE WEEKEND. TEMPS LOOK TO BE BACK TO JUST BELOW AVERAGE
BY FRIDAY. HOWEVER...A FEW DIURNAL INLAND SHOWERS COULD BE POSSIBLE
WITH RETURN MOISTURE THURSDAY AFTERNOON.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 753 PM EDT FRI JUL 11 2014
MVFR CONDITIONS HAVE SETTLED IN AT KCMX WITH RECENT RAINFALL. EXPECT
MVFR CONDITIONS TO BE SHORT-LIVED WITH IMPROVEMENT TO VFR IN THE
NEXT COUPLE OF HRS AS -SHRA DEPART. OTHERWISE...VFR CONDITIONS
SHOULD BE THE RULE AT KIWD/KCMX/KSAW THRU THE EVENING HRS. ISOLD/SCT
SHRA/TSTMS TO THE W OF LAKE SUPERIOR ALONG/AHEAD OF APPROACHING COLD
FRONT SHOULD DISSIPATE BEFORE REACHING UPPER MI AS INSTABILITY
DIMINISHES...SO NOT EXPECTING ANY PCPN AT THE TERMINALS OVERNIGHT.
AS WINDS SHIFT AROUND TO A W TO NW DIRECTION BEHIND COLD FROPA SAT
MORNING...THE UPSLOPE WINDS AT KIWD/KCMX MAY RESULT IN A PERIOD OF
IFR CONDITIONS AND POTENTIALLY LIFR. MVFR CONDITIONS MAY DEVELOP AT
KSAW. ALL TERMINALS SHOULD RETURN TO VFR LATE MORNING INTO THE AFTN.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 429 PM EDT FRI JUL 11 2014
SOUTH WINDS OF UP TO 20 KTS...POSSIBLY 25 KTS AT HIGHER PLATFORMS
ABOVE MARINE LAYER...EXPECTED INTO THIS EVENING WILL DIMINISH
OVERNIGHT WITH WINDS SHIFTING TO SW. AS SCT SHOWERS ASSOCIATED WITH A
WEAK COLD FRONT OR TROUGH MOVE THROUGH LAKE SUPERIOR...FOG WILL BE
POSSIBLE ACROSS THE ENTIRE LAKE WITH THE TROUGH PASSAGE. LIGHT WINDS
WILL CONTINUE THROUGH SUNDAY BEFORE ANOTHER TROUGH PASSES
SOUTHEASTWARD ACROSS LAKE SUPERIOR SUNDAY NIGHT. GUSTY NORTHWEST
WINDS TO 20 KNOTS EXPECTED BEHIND THIS TROUGH EARLY NEXT WEEK AS HIGH
PRESSURE BUILDS OVER THE NORTHERN PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KLUBER
AVIATION...ROLFSON
MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
650 PM CDT FRI JUL 11 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 241 PM CDT FRI JUL 11 2014
LATEST VISIBLE IMAGERY SHOWS AN AREA OF EXTENSIVE LOW CLOUDS NEAR
AND DOWNWIND OF THE SURFACE FRONT/TROUGH AXIS WITH A MORE HEALTHY CU
FIELD TRYING TO DEVELOP NEAR ITS BACK EDGE AND POINTS UPSTREAM.
CLOUDS HAVE MANAGED TO BREAK UP SOUTHEAST OF THERE... INCLUDING THE
SOUTHERN AND EASTERN PORTION OF THE TWIN CITIES... IN THE WAKE OF
THIS MORNING/S CONVECTION. INSTABILITY HAS INCREASE ACROSS THE
WESTERN CWFA... WITH MLCAPE VALUES AOA 500 J/KG WITH NEAR 1500 J/KG
OVER THE FAR WEST. A SUBTLE SHORTWAVE FEATURE CAN BE SEEN IN THE
WATER VAPOR IMAGERY MOVING EAST THROUGH THE ZONAL FLOW ACROSS NORTH
DAKOTA AT THE CURRENT TIME. THIS COULD WORK WITH THE WEAK
CONVERGENCE PRESENT NEAR THE SURFACE TROUGH TO GENERATE SOME
ISOLATED/SCATTERED SHRA/TSRA LATE THIS AFTERNOON INTO EARLY THIS
EVENING. THE NAM IS NOT PARTICULARLY OPTIMISTIC ABOUT ANYTHING OVER
OUR AREA... WHILE THE GFS AND ECMWF MANAGE TO SHOW SOME LIGHT PCPN.
THE CAMS ARE A MIXED BAG... WITH MANY SUCH AS THE HRRR AND A COUPLE
HOPWRF MEMBERS KEEPING THINGS GENERALLY DRY... WHILE A COUPLE HOPWRF
MEMBERS AND THE HIRES WINDOW RUNS MANAGE TO SHOW A FEW CONVECTIVE
CELLS. ALLOWED FOR CHANCE POPS OVER THE AREA FROM LATE AFTERNOON
INTO EVENING TO ACCOUNT FOR THE POSSIBILITY OF A FEW SHRA/TSRA
GETTING GOING. OTHERWISE... THE MAIN LARGE SCALE SUPPORT FOR PCPN
THROUGH TOMORROW LOOKS TO SHIFT TO THE SOUTHERN PORTION OF THE AREA
AND EVEN MORE SO PERHAPS INTO IOWA WHERE THE BAROCLINIC ZONE LOOKS
TO STALL OUT AND THE BEST FRONTOGENESIS AND THETA-E ADVECTION IS
EXPECTED. ALLOWED FOR SOME OF THIS TO SPREAD NORTH DURING THE DAY ON
SATURDAY AS THE FLOW STARTS TO AMPLIFY AND WE SEE A SOMEWHAT
HEALTHIER SHORTWAVE ARRIVE FROM THE WEST.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 241 PM CDT FRI JUL 11 2014
THE LONG TERM PORTION OF THE FORECAST WILL BE GREATLY INFLUENCED BY
A HIGHLY AMPLIFIED LARGE SCALE PATTERN...WITH A DEEP TROUGH
DOMINATING EASTERN CANADA/CONUS...AND RIDGING PREVAILING OVER THE
WEST. SAID PATTERN WILL TRANSLATE TO BELOW NORMAL TEMPERATURES FOR
THE EASTERN TWO-THIRDS OF THE CONUS THROUGH MUCH OF NEXT WEEK.
SATURDAY EVENING SHOULD BRING THE EXIT OF ANY LINGERING SHOWERS
AND THUNDERSTORMS...WITH SKIES CLEARING OUT BY SUNDAY.
THUNDERSTORMS LOOK A BIT LESS LIKELY FOR SUNDAY PER THE 12Z MODEL
RUNS...WITH THE ONLY SLIM POTENTIAL APPEARING TO BE OVER FAR
SOUTHERN MN WHERE DIURNALLY-INDUCED ACTIVITY COULD DEVELOP IN THE
WANING BAROCLINIC ZONE.
MONDAY BRINGS THE ARRIVAL OF THE UPPER LOW OVERHEAD...MADE EVIDENT
BY SCATTERED SHOWERS AND TEMPERATURES NEARING 20 DEGREES BELOW
NORMAL. HIGHS IN THE LOW/MID 60S WILL COMBINE WITH BREEZY NORTHWEST
WINDS TO MAKE FOR A CHILLY DAY.
TUESDAY THE TROUGH CENTER WILL HAVE SHIFTED EAST OF THE AREA...SO
SHOWER CHANCES WILL BE MAINLY CONFINED TO WEST CENTRAL WI
COUNTIES. HIGHS WILL MODERATE A TAD...BUT WILL LIKELY STILL TOP
OUT IN THE MID/UPPER 60S.
WEDNESDAY AND THURSDAY THE LOW LIFTS INTO QUEBEC AND HEIGHTS RISE
A BIT. THIS WILL MEAN GRADUALLY MODERATING TEMPERATURES AND DRY
WEATHER...WITH HIGHS IN THE LOW/MID 70S ON WEDNESDAY...AND
MID/UPPER 70S FOR THURSDAY.
BY FRIDAY THE FLOW TRANSITIONS TO NEARLY ZONAL ACROSS THE
CONUS...AS WEAK MID LEVEL TROUGHING OVER SOUTHERN
SASKATCHEWAN/MANITOBA INDUCES HIGH PLAINS SURFACE CYCLOGENESIS.
SOUTHERLY FLOW AHEAD OF THIS FEATURE WILL AID IN FURTHER TEMPERATURE
MODERATION ON FRIDAY...WITH HIGHS IN THE UPPER 70S AND LOWER 80S.
STILL LOOKS TO BE DRY ON FRIDAY...ALTHOUGH THE AFOREMENTIONED
TROUGH SHOULD FACILITATE SHOWER AND THUNDERSTORM CHANCES AT SOME
POINT NEXT WEEKEND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 650 PM CDT FRI JUL 11 2014
A COLD FRONT STRETCHED FROM KINL TO KAXN TO KHON EARLY THIS
EVENING. ALTHOUGH SCATTERED STORMS ARE OCCURRING ACROSS NE MN
ATTM...ONLY ISOLATED SHRA/TSRA ARE EXPECTED THIS EVENING ALONG THE
FRONT ACROSS CENTRAL AND SOUTHERN MN. A FEW SHOWERS ARE POSSIBLE
AS WELL THIS EVENING ACROSS WEST CENTRAL WI. THE MAIN CONCERN
OVERNIGHT IS HOW EXTENSIVE MVFR OR LOWER CEILINGS MAY BECOME IN
THE VICINITY OF THE FRONT AS IT MOVES VERY SLOWLY EASTWARD.
CONFIDENCE IS HIGHEST FOR IFR OR LOWER CONDITIONS DEVELOPING LATE
FOR KRNH AND KEAU. THESE SITES WILL SLOWLY CLEAR THIS EVENING IN
THE WAKE OF SHOWERS TODAY WITH A VERY MOIST LOW LEVEL PROFILE.
IFR VSBYS HAVE ALSO BEEN INCLUDED FOR KRWF...KSTC AND KMSP. LOW
CEILINGS WERE NOT INCLUDED AT THESE SITES DUE TO INCOMING MID/HIGH
LEVEL CLOUDS DURING THE OVERNIGHT. RAIN WILL LIKELY SPREAD INTO
WEST CENTRAL THROUGH SOUTHERN MINNESOTA ON SATURDAY AS A WAVE OF
LOW PRESSURE PRESSURE PASSES TO OUR SOUTH. PREVAILING SHOWERS
MENTIONED FOR KRWF WITH VCSH AT KMSP FOR THE AFTERNOON.
OTHERWISE...VFR EXPECTED.
KMSP...THE LOW VFR CEILINGS ARE EXPECTED TO SCATTERED THIS EVENING
WITH CONFIDENCE HIGH ON MVFR/IFR FOG FOR THE OVERNIGHT HOURS. A
COLD FRONT SHOULD PASS THE AIRFIELD AROUND 08Z. ORGANIZED SHOWERS
WILL BE MAINLY SOUTH OF THE AIRFIELD SATURDAY AFTERNOON.
/OUTLOOK FOR KMSP/
SATURDAY NIGHT...VFR. WEST WINDS LESS THAN 10 KTS BECOMING
NORTHWEST.
SUNDAY...VFR. NORTHWEST WINDS 10 TO 15 KTS.
SUNDAY NIGHT. MVFR POSSIBLE WITH A CHANCE OF SHRA/TSRA. NORTHWEST
WINDS 5 TO 10 KTS.
MONDAY...MVFR POSSIBLE WITH A CHANCE OF SHRA/TSRA. NORTHWEST WINDS
15 TO 20 KTS.
MONDAY NIGHT...MVFR POSSIBLE. NORTHWEST WINDS 10 KTS.
TUESDAY...VFR. NORTHWEST WINDS 10 TO 15 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...TRH
LONG TERM...LS
AVIATION...RAH
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
327 PM CDT THU JUL 10 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 325 PM CDT THU JUL 10 2014
MAIN CONCERN FOR THE SHORT TERM IS TURNING OUT TO BE THE POTENTIAL
FOR HEAVY RAIN TONIGHT OVER WESTERN MN BASED ON LATEST HI-RES CAMS.
THIS AFTERNOON...SRLY LOW LEVEL WINDS HAVE BECOME WELL ESTABLISHED
AS HIGH PRESSURE HAS NOW PUSHED OFF TO MICHIGAN. THESE SRLY WINDS
HAVE FINALLY BROUGHT THE CANADIAN SMOKE PLUME THAT WAS LINGERING
JUST TO OUR SW THE PAST COUPLE OF DAYS UP INTO CENTRAL AND SRN
MN...HENCE THE MILKY COLOR IN THE SKY AND OCCASIONAL HAZE REPORTS
ACROSS THE AREA THIS AFTERNOON. BACK TO THE WEST...A SHORT WAVE CAN
BE SEEN APPROACHING WRN MN...THOUGH THIS HAS DONE NOTHING MORE THAN
CREATE MAINLY VIRGA...AND THIS IS EXPECTED TO BE THE CASE AS IT
WORKS ACROSS MN THIS EVENING. INSTEAD...THE MAIN WAVE DRIVING THE
WEATHER ACROSS THE NRN PLAINS IS THE CUT-OFF H5 LOW CURRENTLY
SPINNING FROM ALBERTA INTO SASKATCHEWAN. THIS WAVE IS WHAT IS
FORCING THE LLJ TO BE BACK MORE ACROSS CENTRAL INTO THE ERN DAKOTAS
TODAY.
FOR THIS AFTERNOON INTO TONIGHT...FAVORED THE FORECAST FOR POPS AND
QPF TOWARD THE RAP/ECMWF ALONG WITH JUST ABOUT ANY HI-RES CAM YOU
CAN FIND THAT WAS RUN AT 12Z OR LATER. ALL OF THESE MODELS SHOW
THUNDERSTORMS DEVELOPING OVER NE SODAK AROUND 21/22Z AND SLOWLY
WORKING EAST INTO WRN MN THIS EVENING. ALL HI-RES MODELS SHOW 2-4
INCHES OF RAIN FALLING IN THE GENERALLY VCNTY OF THE NE SODAK/WRN MN
BORDER. LOOKING AT THE RAP...THIS LOOKS TO BE TIED TO WHAT IS
HAPPENING IN THE 925-850MB LAYER. THE RAP HAS BEEN PRETTY CONSISTENT
WITH SHOWING MOISTURE TRANSPORT IN THIS LAYER INCREASING THIS
AFTERNOON ACROSS SE SODAK...WITH THE EDGE OF IT UP INTO NE SODAK. IN
ADDITION TO THAT...THE RAP SHOWS A STRONG FGEN SIGNAL AT THE NOSE OF
THIS LLJ. THE REASON FOR THE HEAVY PRECIP SIGNAL IS THIS LLJ AND ITS
ASSOCIATED FGEN REMAIN MORE OR LESS STATIONARY OUT NEAR THE MN/SD
BORDER THROUGH ABOUT 6Z. WITH THIS FORCING REMAINING
STATIONARY...THERE WILL BE A PERIOD THROUGH ABOUT 6Z WHERE THE
ACTIVITY CAN TRAIN OUT THERE...BEFORE EVERYTHING STARTS TO BECOME
MORE PROGRESSIVE LATE TONIGHT AS THE CANADIAN UPPER LOW MOVES TOWARD
MANITOBA. QPF GRIDS USED WERE A BLEND OF THE SHORT TERM CAMS
TEMPERED WITH THE 12Z ECMWF. THIS RESULTED IN 1-2 INCHES OF QPF
THROUGH FRI MORNING OUT IN WRN MN...WHICH MAY STILL BE CONSERVATIVE
CONSIDERING SOME OF THE HI-RES MODELS HAVE BEEN SHOWING THE
POTENTIAL FOR ISOLATED RAINFALL AMOUNTS OVER 5 INCHES TONIGHT...SO
THIS IS SOMETHING THAT CERTAINLY BEARS SOME WATCHING.
THROUGH THE REST OF THE SHORT TERM...THE LLJ AND SFC FRONT WILL
SLOWLY WORK EAST WITH TIME DURING THE MORNING ON FRIDAY...WITH BEST
RAINFALL CHANCES FOR ERN MN/WRN WI LIKELY COMING DURING THE MORNING
AS REMNANTS OF TONIGHTS ACTIVITY SHIFTS EAST. BACKED OFF SOME ON
POPS FRIDAY AFTERNOON...AS CAMS ARE FAIRLY SPARSE WITH ACTIVITY AS
WE LOOSE THE DEFINITION ON THE SFC FRONT...WHICH WILL COINCIDE WITH
A WEAKENING OF THE LLJ AS WE GET INTO SUBSIDENCE ASSOCIATED WITH THE
RIGHT ENTRANCE REGION OF THE UPPER JET WORKING ACROSS THE
INTERNATIONAL BORDER. WITH LESS ACTIVITY EXPECTED...ALSO BOOSTED
TEMPS A FEW DEGREES OUT IN WRN WI AS IT IS NOT LOOKING AS LIKELY FOR
FRIDAY TO BE DOMINATED BY CLOUDS AND RAIN AS WAS PREVIOUSLY
ANTICIPATED.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 325 PM CDT THU JUL 10 2014
AS WE PROGRESS THROUGH THE SATURDAY-THURSDAY PERIOD WE/LL SEE QUITE
THE EVOLUTION OF LARGE SCALE FEATURES AND WEATHER ACROSS THE AREA.
THINGS WILL START OUT WARM WITH THE UPPER JET NORTH OF THE AREA...
BUT AN UNSEASONABLY DEEP UPPER LOW WILL DROP SOUTH/EAST FROM CENTRAL
CANADA INTO THE UPPER MIDWEST AND GREAT LAKES REGION DURING THE
SUNDAY NIGHT THROUGH TUESDAY PERIOD. THIS WILL BRING VERY COOL
TEMPERATURES TO MUCH OF THE REGION... WITH THE HEART OF THE COLD AIR
TRACKING ACROSS MINNESOTA AND POINTS EAST. SOME PCPN CHANCES WILL
LOITER ACROSS THE REGION SATURDAY INTO SUNDAY PRIOR TO THE ARRIVAL
OF THE COLD FRONT AND UPPER TROUGH... WITH DIURNAL CHANCES FOR PCPN
AFTER THAT AS THE UPPER COLD POOL SWINGS ACROSS THE REGION. BEST
CHANCES FOR PCPN PRIOR TO FROPA WILL BE ACROSS THE SOUTHERN PORTIONS
OF THE AREA WHERE THE BAROCLINIC ZONE AND BEST INSTABILITY ARE
PROGGED... WITH CHANCES FOR DIURNAL SHRA FOLLOWING FROPA LOCATED
OVER EASTERN AREAS WHERE BOUNDARY LAYER CYCLONIC FLOW WILL BE MOST
PREVALENT AND LOW-MID LEVEL LAPSE RATES WILL BE STEEPEST BENEATH THE
MID-UPPER LEVEL COLD POOL. WE WILL SEE RIDGING BEGIN TO WORK INTO
THE AREA AFTER TUESDAY... WITH DRY WEATHER AND MODERATING
TEMPERATURES FOR THE LAST FEW DAYS OF THE FORECAST PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1250 PM CDT THU JUL 10 2014
MAIN DISTURBANCE IS NOW OVER NORTHERN SODAK WHICH WILL BE
GENERATING SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND TONIGHT AS
IT HEADS EAST TOWARD MN. DEFORMATION AREA TO THE WEST OF THIS
DISTURBANCE ALONG THE MT/WY BORDER WILL ALSO FOSTER STORM
DEVELOPMENT THIS EVENING...SO IT LOOKS LIKE A FAIRLY STORMY
EVENING AND OVERNIGHT ACROSS WEST CENTRAL AND PORTIONS OF CENTRAL
MN. HEAVY RAIN POTENTIAL IS INCREASING WITH SEVERAL INCHES
POSSIBLE...BUT IT IS STILL SOMEWHAT UNCLEAR WHICH TAF SITES WILL
BE MOST IMPACTED. AT THIS POINT IT LOOKS LIKE IT WILL SET UP JUST
SOUTH OF AXN/STC AND NORTH OF RWF THROUGH 06Z...EXPANDING EASTWARD
TOWARD MSP BETWEEN 08-11Z. MAINLY VFR CONDITIONS EXPECTED...
HOWEVER HEAVY RAINFALL WOULD BRING MUCH LOWER CONDITIONS.
KMSP...LITTLE CONCERNS THIS AFTERNOON AND EVENING. BIGGEST CONCERN
COMES LATE TONIGHT AND FRIDAY MORNING IF MESOSCALE MODELS ARE
CORRECT IN BRINGING A NARROW BAND OF HEAVY RAINFALL.
/OUTLOOK FOR KMSP/
SAT...VFR WITH MVFR/SHRA/TSRA POSSIBLE. WIND NW AT 5 KTS.
SUN...VFR WITH MVFR/SHRA/TSRA POSSIBLE. WINDS W AT 5-10 KTS.
MON...VFR WITH MVFR CIGS/SHRA POSSIBLE. WIND NW AT 10-20 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...TRH
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1041 AM CDT THU JUL 10 2014
.UPDATE...
ADJUSTED POPS AND HOURLY TEMPS REST OF TODAY.
.SHORT TERM...
SMALL MCS VORT CENTER CONTINUES TO MOVE SE AND PRODUCE SHRA/TSRA
ACROSS SE 1/3 OF FORECAST AREA LATE THIS MORNING. IN ITS WAKE...SUN
IS BREAKING OUT AND TEMPERATURES ARE BEGINNING TO RESPOND. WEAK
SURFACE BOUNDARY APPEARS TO BE DROPPING THROUGH THE TENN VALLEY AND
MID SOUTH REGIONS. BLENDED TOTAL PW CLEARLY SHOWS DEEP MOISTURE
POOLING AHEAD OF THIS BOUNDARY IN A NW-SE ORIENTATION FROM CENTRAL OK
ACROSS OUR AREA TOWARD FL PANHANDLE. WIDELY SCT SHRA/TSRA CONTINUE TO
POP UP IN THIS MOIST/UNSTABLE AIRMASS BEHIND LEAD VORTICITY CENTER OVER
SE MS. LARGER MCS CURRENTLY DROPPING SE ACROSS EASTERN OK AND FAR NW
AR WILL CONTINUE TO PUSH SE TOWARD OUR AREA. HRRR SEEMS A BIT TOO
SLOW WITH DROPPING THIS FEATURE SE...AND EXPECT THE COMINBATION OF
HEATING...BOUNDARY AND APPROACH OF THIS SYSTEM WILL YIELD AN INCREASE
IN COVERAGE OF SHRA/TSRA FROM THE NW LATER THIS AFTERNOON.
ADDITIONALLY...DAYTIME HEATING AND RESIDUAL BOUNDARIES WILL ALLOW
FORMATION OF AT LEAST WIDELY SCT SHRA/TSRA ELSEWHERE. HAVE ADJUSTED
POPS TO ACCOUNT FOR TREND OF HIGHEST POPS IN SE REST OF THIS AM...AND
THEN IN THE NW LATER TODAY. MAX TEMPS SEEM OK BASED ON CURRENT
TRENDS...BUT ADJUSTED HOURLY TEMPS TO ACCOUNT FOR COOLER READINGS
THIS MORNING DUE TO CLOUDS/PRECIP. /08/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 88 68 95 68 / 45 14 5 9
MERIDIAN 88 67 95 65 / 67 13 5 9
VICKSBURG 87 66 96 66 / 48 14 7 8
HATTIESBURG 86 70 96 70 / 68 21 19 7
NATCHEZ 86 69 95 70 / 46 18 17 6
GREENVILLE 89 69 96 70 / 53 5 2 8
GREENWOOD 89 67 94 66 / 47 5 2 9
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
AEG
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
825 AM CDT THU JUL 10 2014
.UPDATE...INCREASED POPS FOR THIS MORNING.
.SHORT TERM...RADAR AND SATELLITE SHOW A SMALL MCS MOVING ACROSS
CENTRAL AND SOUTHERN MS...WITH A FEW SHOWERS AND STORMS ALSO
DEVELOPING OVER SE AR IN ASSOCIATION WITH ANOTHER WAVE DROPPING ESE
ACROSS AR. GIVEN THIS...HAVE UPDATED FORECAST TO ADJUST TIMING OF
PRECIPITATION TODAY TO MOVE AWAY FROM CONCEPT OF HIGHER POPS IN THE
AFTERNOON. IN FACT...11Z HRRR SHOWS BULK OF PRECIPITATION OCCURRING
THIS MORNING WITH LITTLE IN WAY OF REDEVELOPMENT DURING THE
AFTERNOON. LOCAL WRF IS MORE BULLISH WITH AFTERNOON ACTIVITY IN
SOUTHERN AREAS...BUT IT DOES NOT HAVE A GOOD HANDLE ON WHAT IS GOING
ON NOW WHILE HRRR DOES. GIVEN SATELLITE SHOWING UPSTREAM ACTIVITY
OVER AR/OK WILL NOT MESS WITH AFTERNOON FORECAST YET...BUT COULD LOOK
AT ADJUSTING POPS FOR THE AFTERNOON DOWN IN SOME AREAS WITH A MIDDAY
UPDATE. TEMPS COULD ALSO NEED TO BE ADJUSTED AT THAT TIME AS
WELL...DEPENDING ON PRECIP COVERAGE THIS AM MAY BE TOO WARM IN
CENTRAL/SOUTHERN AREAS. /08/
&&
.PREV DISCUSSION... /ISSUED 349 AM CDT THU JUL 10 2014/
SHORT TERM...TODAY THROUGH FRIDAY NIGHT...
LATEST SATELLITE IMAGERY SHOWED AN UPPER TROUGH OVER THE MISSISSIPPI
VALLEY WITH SOME WEAK UPPER DIVERGENCE. A WEAK SHORTWAVE ON THE BASE
OF THE TROUGH WAS BRINGING IN SOME CONVECTION ACROSS THE REGION. THE
WEAK SURFACE FRONTAL BOUNDARY CURRENTLY LOCATED TO THE NORTH OF THE
AREA WILL DROP SOUTH INTO THE AREA THIS AFTERNOON. PWATS AROUND 2
INCHES WILL DECREASE FROM THE NORTH AS THE WEAK FRONT MOVES INTO THE
REGION. PWATS WILL DECREASE TO AROUND 1-1.3 INCHES BEHIND THE
BOUNDARY. A DRY SLOT OF LESS THAN ONE INCH WILL MOVE INTO THE REGION
FRIDAY NIGHT. WITH LITTLE UPPER SUPPORT EXPECT THE WEAK SURFACE
FRONTAL BOUNDARY TO STALL ACROSS AREA BY THIS EVENING. SO WILL KEEP
CHANCES OF CONVECTION GOING THROUGH THIS EVENING UNTIL AFTER SUNSET.
WITH MARGINAL INSTABILITY AND WEAK SHEAR UNDER DECENT CLOUD COVER
EXPECT THESE STORMS TO REMAIN SUB-SEVERE...BUT A STRONG STORM OR TWO
LOOK POSSIBLE THIS AFTERNOON AND EARLY EVENING WITH DAYTIME HEATING.
THERE ALSO COULD BE SOME LOCALLY HEAVY DOWNPOURS WITH SOME LIMITED
FLOODING POTENTIAL WITH THE LIGHT CORFIDI VECTORS. WITH LACK OF UPPER
SUPPORT THE ACTIVITY SHOULD DIMINISH THIS EVENING. ON FRIDAY THE
UPPER TROUGH WILL LIFT EAST OF THE REGION AS UPPER RIDGING BUILDS IN
FROM THE WEST. THIS WILL PUSH THE SURFACE BOUNDARY AWAY FROM THE
REGION. ON FRIDAY EXPECT DIURNAL CONVECTION TO BE AROUND WITH
ISOLATED COVERAGE ACROSS THE SOUTH DURING THE AFTERNOON WHICH WILL
DIMINISHING BY EVENING. WE SHOULD GET BETTER INSOLATION FOR WARMER
TEMPS ON FRIDAY.
AS FAR AS TEMPS ARE CONCERN WENT CLOSER TO NAM GUIDANCE FOR TODAY HIGHS
IN THE MID TO UPPER 80S DUE TO CLOUD COVER. FOR FRIDAY WENT CLOSER
TO THE WARMER GMOS GUIDANCE IN THE MID 90S. FOR NIGHTLY LOWS WENT
CLOSER TO THE MILDER BLEND OF NAM/MAV GUIDANCE WITH LOWS IN THE MID 60S
TO AROUND 70. AS FAR AS POPS MADE SOME ADJUSTMENTS TO MOS POPS WITH
BETTER COVERAGE FOR TODAY. WENT CLOSE TO MOS POPS FOR TONIGHT AND
FRIDAY./17/
LONG TERM...SATURDAY THROUGH THURSDAY...THE FIRST HALF OF THE
EXTENDED WILL BE FAIRLY QUIET AS UPPER RIDGING WILL BE IN PLACE
OVERHEAD. THIS WILL LEAD TO MOSTLY DRY CONDITIONS AND WARM
TEMPERATURES. THERE COULD BE SOME CHANCE FOR AN ISOLATED STORM IN
THE SOUTH THROUGH THE WEEKEND AS DAYTIME HEATING WILL COMBINE WITH
ENOUGH INSTABILITY AND MOISTURE IN PLACE. THE GFS SHOWED SOME DRIER
PW VALUES COMING THROUGH THE REGION WHICH WOULD PRECLUDE
SHOWERS/STORMS FROM DEVELOPING. THE NAM AND ECMWF ON THE OTHER HAND
CONTINUE TO SHOW PW VALUES AROUND 1.5 TO NEAR 2 INCHES THROUGH THE
WEEKEND. THIS...ALONG WITH HIGHS REACHING INTO THE MID 90S...COULD
SPARK SOME CONVECTION AND LEANED CLOSER TO THE NAM/ECMWF.
HEADING INTO THE WEEK...THE UPPER RIDGING GIVES WAY TO A RATHER
LARGE UPPER TROUGH THAT WILL BE LOCATED ACROSS THE GREAT LAKES
REGION. THIS WILL TAKE UP RESIDENCE THROUGH THE REST OF THE PERIOD.
A SERIES OF WAVES WILL MOVE THROUGH THE BASE OF THE TROUGH...ONE OF
WHICH WILL SEND A COLD FRONT IN OUR DIRECTION. THIS FRONT WILL MOVE
INTO THE ARKLAMISS TUESDAY INTO WEDNESDAY. BOTH THE GFS AND THE
ECMWF BRING THE FRONT ALL THE WAY THROUGH THE CWA BY EARLY THURSDAY.
GIVEN PLENTY OF MOISTURE AHEAD OF THE FRONT...WE WILL SEE A BETTER
CHANCE FOR SHOWERS AND STORMS COME TUESDAY AND WEDNESDAY. BEHIND THE
FRONT. ALSO BEHIND THE FRONT...SOME COOLER AIR WILL BE POSSIBLE WITH
SOME BELOW NORMAL TEMPERATURES POSSIBLE. /28/
&&
.AVIATION...
A FRONTAL BOUNDARY PUSHING SOUTH ACROSS THE AREA WILL
BRING ADDITIONAL SHRA/TSRA ACTIVITY FOR TODAY UNTIL AROUND 01Z.
OUTSIDE OF CONVECTION...MVFR CATEGORY FOG AND A FEW PATCHY AREAS OF
LOW STRATUS WILL BE COMMON DURING THE EARLY MORNING HOURS.
OTHERWISE...VFR CONDITIONS WILL PREVAIL OUTSIDE OF STORMS./17/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 88 68 95 68 / 55 14 5 9
MERIDIAN 88 67 95 65 / 56 13 5 9
VICKSBURG 87 66 96 66 / 50 14 7 8
HATTIESBURG 86 70 96 70 / 59 21 19 7
NATCHEZ 86 69 95 70 / 60 18 17 6
GREENVILLE 89 69 96 70 / 27 5 2 8
GREENWOOD 89 67 94 66 / 27 5 2 9
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
AEG
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
1100 PM MDT Wed Jul 9 2014
UPDATED AVIATION SECTION
.DISCUSSION...
Update forthcoming. Satellite imagery shows moisture continuing to
be advected over southwest Montana this evening where the airmass
remains somewhat unstable. The resulting showers and isolated
thunderstorms will persist through 06z, mainly south of a KDLN-KBZN
line. Latest RUC run, as well as HRRR analysis, indicate convective
activity will shift to the east after 06z and decrease in areal
coverage and intensity. North of the KDLN-KBZN line the airmass is
much more stable and no precipitation is expected overnight.
Temperatures look on track.
&&
.AVIATION...
UPDATED 0500Z.
VFR conditions are expected to continue across the area at least
through Thursday evening. Clouds and showers will continue to
diminish through 10Z across central Montana as a disturbance moves
through the area. A weak cold front will accompany the disturbance,
shifting the southwesterly winds more northwesterly from northwest
to southeast over the central Montana plains between 09Z and 15Z.
Clouds will then increase again after 18Z as the mid level flow
becomes more northwesterly and brings moisture into the area from
Canada. Surface winds will decrease during this time and there will
be a chance of showers along the Canadian border.
Coulston
&&
.PREV DISCUSSION...Issued 232 PM MDT Wed Jul 9 2014
Today through Friday...Southwest Montana will become slightly
unstable this afternoon as an increase in moisture should bring
scattered thunderstorms to the area. Moderate shear could allow
for the development of some stronger cells. Precipitable water is
somewhat high meaning some storms could produce brief heavy rain.
Activity diminishes by midnight tonight. Thursday and Friday look
to be much of the same with the days starting out quiet before
afternoon convection over far Southwest Montana. Temperatures
will remain warm and winds may be a bit breezy at times.
Friday night through Wednesday...The main upper level ridge of high
pressure that is residing over the region will slowly be
shifting/retrograde a bit more to the west from Saturday through
Tuesday. As a result...the warmest temperatures will likely be
staying west of the divide and over the Pacific Northwest.
Never-the-less...it will still be quite warm/very warm for Saturday
and Sunday...then seasonable/warm temperatures will reside over the
region from Monday thru Wednesday. In terms of precipitation...no
real organized areas of precipitation is expected from Friday
through Sunday...other than some passing monsoonal moisture. Thus
the chances for thunderstorms are generally isolated during this
period...and mainly over Central and Southwest Montana. For
Monday/Tuesday...the GFS tries to develop a bit more widespread
thunderstorm activity along the front range of the Rockies and then
southward into Southwest MT. Thus pops have been increased a
bit...but overall coverage still looks to be scattered at this time.
The thunderstorm activity starts to decrease a bit by next
Wednesday...as the upper level ridge will start to shift/wobble back
east a bit...also resulting in slightly warmer temperatures. Brusda
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 60 86 56 84 / 10 10 10 10
CTB 55 79 50 80 / 10 10 20 0
HLN 62 90 57 88 / 20 10 10 10
BZN 57 87 53 87 / 30 10 20 20
WEY 47 78 44 81 / 40 20 20 40
DLN 57 86 54 88 / 30 10 10 10
HVR 61 88 53 87 / 10 10 20 10
LWT 60 86 53 84 / 30 10 10 10
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
weather.gov/greatfalls
www.twitter.com/NWSGreatFalls
www.facebook.com/US.NationalWeatherService.GreatFalls.gov
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
615 PM CDT FRI JUL 11 2014
.SHORT TERM...(TONIGHT THROUGH MONDAY)
ISSUED AT 218 PM CDT FRI JUL 11 2014
MAIN ISSUES CONTINUE TO BE POSSIBLE SEVERE STORMS ALONG WITH
PERIODS OF EXCESSIVE RAINFALL.
THIS AFTN THROUGH SATURDAY...DISSIPATING CLOUD COVER/AFTN HEATING
WILL ALLOW ENVIRONMENT TO QUICKLY DESTABILIZE WITH BOTH NAM/GFS
ADVERTISING MUCAPES AROUND 3500 J/KG...LI -1O. THIS IN COMBINATION
WITH FAVORABLE EFF SHEAR/DEEP LYR SHEAR PRETTY MUCH SUGGEST INITIAL
DEVELOPMENT WILL BE SUPERCELLULAR IN NATURE BEFORE TRANSITIONING TO
LARGE CONVECTIVE COMPLEX. THUS SEVERE TSTMS A DISTINCT POSSIBILITY.
LIKELY THAT TSTM INITIATION WILL OCCUR SOMEWHERE IN THE VICINITY OF
WRN SD/NW NEB WHERE STRONG LLVL MOISTURE ADV WILL BE PERPENDICULAR
TO ZONE OF INTENSE BNDRY LYR THETA-E CONVG. CONVECTION WILL INCREASE
IN AREAL COVERAGE THEN OVERNIGHT ALONG THE SD/NEB BORDER WHERE
LLVL MOISTURE CONVG/STRONG 310K-315K ISENTROPIC UPGLIDE WILL BE
FOCUSED. APPEARS THAT WAA FORCING WILL BE MAINTAINED DURING THE
OVERNIGHT HOURS WITH 850-250MB DIFF DIVG CONTRIBUTING TO SYNOPTIC
SCALE ASCENT. IN ADDITION...PROLONGED RAINFALL EVENT APPEARS
PROBABLE MAINLY OVER THE NRN CWA ALONG THE NEARLY STALLED FRONTAL
BNDRY. KI VALUES 40-45 INDICATE DEEP LYR MOISTURE WILL BE IN PLACE
AT THAT TIME. PRECIP EFFICIENCY WILL BE VERY FAVORABLE CONSIDERING
DEPTH OF WARM CLOUD LYR ALONG WITH PWS OF 2" OR MORE.
CANNOT DISCOUNT SEVERE TSTM POTENTIAL SAT AFTN WHEN INSTABILITY
RAMPS UP AGAIN ALONG SFC BNDRY. CONDITIONS IMPROVING THEN MONDAY
AFTN.
CONVECTIVE PCPN WILL STILL BE POSSIBLE AT LEAST THRU MONDAY MORNING
WHEN A SECONDARY SHOT OF CAA PRESSES SWD INTO THE CNTRL PLAINS.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 218 PM CDT FRI JUL 11 2014
DETERMINISTIC ECM/GFS AS WELL AS ECMENS/CMCENS AGREE LARGE SCALE
PATTERN WILL BE RELATIVELY STAGNANT INTO NEXT WEEK HIGHLY ANOMALOUS
CLOSED UPPER LOW ENVELOPING THE ERN CONUS WITH AN UPSTREAM RIDGE
OVER THE WRN CONUS. PATTERN WILL BE QUITE FAVORABLE FOR DRY/COOL
AIRMASS TO FILTER INTO THE CNTRL PLAINS. THIS AIRMASS WILL BE STRONG
ENOUGH TO KEEP MAX/MIN TEMPS BELOW NORMAL THE DURATION OF THE
EXTENDED PDS. STILL LOOKS POSSIBLE MORNING LOWS MONDAY AND TUESDAY
WILL BE APPROACHING NEAR RECORD VALUES.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 615 PM CDT FRI JUL 11 2014
TSTM CHANCES ARE HIGHEST AT KOFK ACCORDING TO LATEST HRRR MODEL
RUNS WHICH KEEP MOST PCPN IN OUR AREA ACROSS NORTHEAST NEBRASKA
OVERNIGHT. DID MENTION SOME LOWER CEILINGS AND VSBYS THERE WITH
TSRA. FOR KOMA AND KLNK...CHANCES SEEM LOWER AND DID NOT MENTION
ANY TSTMS FOR NOW AND EXPECT MAINLY VFR CONDITIONS. SOME FOG IS
POSSIBLE TOWARD SUNRISE...SO INCLUDED A TEMPO GROUP FOR THAT.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...DEE
LONG TERM...DEE
AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
330 AM CDT THU JUL 10 2014
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 330 AM CDT THU JUL 10 2014
TEMPERATURES AND TSTM CHANCES WILL PROVIDE THE PRIMARY FORECAST
CHALLENGES IN THIS PERIOD. LARGE SCALE PATTERN SHOULD UNDERGO SOME
CHANGES. UPPER LEVEL RIDGE INITIALLY CENTERED OVER THE FOUR CORNERS
REGION EXPANDS EASTWARD THROUGH SATURDAY AS A STRONG SHORTWAVE MOVES
ACROSS CANADA. THE CENTER OF THE RIDGE THEN RETROGRADES INTO EARLY
NEXT WEEK WHILE FLOW AMPLIFIES. TOWARD THE END OF THE PERIOD A
CLOSED LOW AT 500 MB WILL DROP DOWN FROM CANADA INTO THE GREAT
LAKES REGION.
TODAY...SOUTHERLY SURFACE WINDS WILL INCREASE ACROSS THE CENTRAL
PLAINS AS HIGH PRESSURE CONTINUES TO MOVE OFF TO THE EAST. MAIN
AREA OF TSTMS SHOULD MOVE OUT OF THE FORECAST AREA BY AROUND
SUNRISE...BUT WILL HOLD ONTO SOME LOW POPS FOR PARTS OF SOUTHEAST
NEBRASKA INTO MID MORNING. EXPECT HIGHS TO BE MAINLY IN THE LOWER
TO MID 80S.
TONIGHT...BETTER MOISTURE WILL BE IN PLACE BOTH SURFACE AND ALOFT.
PRECIPITABLE WATER VALUES INCREASE INTO THE 1.50 TO 2.00 RANGE AND
THE 00Z NAM SUGGESTS SOME VALUES OVER 2.00 INCHES. COMBINATION OF
INCREASING MOISTURE AND A 50 KNOT LOW LEVEL JET WITH
WEST/NORTHWEST MID LEVEL FLOW SHOULD LEAD TO A TSTM COMPLEX
SOMEWHERE IN THE REGION. MODELS ARE NOT IN VERY GOOD AGREEMENT ON
LOCATION. FOR NOW TENDED TO FAVOR 00Z GFS FOR PLACEMENT OF HIGHEST
RAIN CHANCES AND HEAVIEST RAIN AMOUNTS. SO...THAT KEEPS HIGHEST
POPS FOR ABOUT THE NORTH OR NORTHEAST HALF OF THE AREA.
STORMS MAY LINGER INTO FRIDAY MORNING...THEN WEAKEN. HIGHS SHOULD
REACH 85 TO 90 MOST LOCATIONS WITH SOME LOWER 90S NEAR THE KANSAS
BORDER. FRONTAL BOUNDARY IS FORECAST TO SAG SOUTHWARD FRIDAY
NIGHT INTO SATURDAY. KEPT POPS MOSTLY 30 TO 50 PERCENT AS OUR AREA
WILL BE NORTH OF THE FRONT IN A FAVORABLE REGIME FOR PCPN...
ESPECIALLY LATE FRIDAY NIGHT. HIGHS SATURDAY WILL PROBABLY BE A
BIT COOLER WITH MID 80S NORTH AND UPPER 80S SOUTH.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM CDT THU JUL 10 2014
HIGH TEMPERATURES WILL BE A LITTLE BELOW NORMAL AT THE BEGINNING
OF THIS PERIOD...THEN COOL TO WELL BELOW TYPICAL VALUES FOR MID
JULY. HIGHLY AMPLIFIED FLOW WILL ALLOW A CANADIAN AIRMASS TO DROP
DOWN INTO THE AREA AS RIDGE AXIS ALOFT BUILDS OVER WESTERN NORTH
AMERICA. KEPT SOME MENTION OF PCPN THROUGH TUESDAY...THEN WENT
WITH POPS 14 OR LESS AS COOLER AND DRIER AIR SETTLES IN.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1150 PM CDT WED JUL 9 2014
POCKETS OF CONVECTION CONTINUE JUST WEST OF THE FORECAST AREA AT
05Z WITH KLNK STILL REPORTING OCCASIONAL SHOWERS. RAP STILL
INDICATES A GRADUAL EASTWARD SHIFT OF THE CENTRAL NEBRASKA SYSTEM
AS LOW LEVEL JET AND MOISTURE ADVECTION TRANSLATE INTO EASTERN
NEBRASKA BY 12Z AND CONTINUES THROUGH THE MORNING. HAVE LIMITED A
PERIOD OF CONVECTION AT KLNK DURING THE EARLY MORNING AND AT KOMA
AFTER 15Z. KOFK IS EXPECTED TO BE ON EDGE OF ACTIVITY THROUGH THE
PERIOD. LIMITED CONFIDENCE AT THIS TIME HOWEVER AND WILL NEED TO
MONITOR DEVELOPMENT TRENDS NEXT FEW HOURS TO SEE IF RAP IS HEADING
IN THE RIGHT DIRECTION WITH ITS SOLUTION.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
233 AM CDT THU JUL 10 2014
.SYNOPSIS...
ISSUED AT 318 PM CDT WED JUL 9 2014
H5 ANALYSIS FROM THIS MORNING HAS A CONTINUATION OF THE
RIDGE/TROUGH REGIME ACROSS THE CONUS. A TROUGH OF LOW PRESSURE
EXTENDED SOUTH FROM NORTHERN CANADA INTO THE OHIO VALLEY. RIDGING
EXTENDED NORTH FROM HIGH PRESSURE LOCATED OVER SRN UTAH INTO
NORTHERN PORTIONS OF ALBERTA AND SASKATCHEWAN. ACROSS THE CENTRAL
AND NORTHERN PLAINS...A NICE 40 TO 45 KT SPEED MAX EXTENDED FROM
WESTERN NEBRASKA NWD INTO WESTERN SD AND MT. THIS FEATURE ALONG WITH
A VERY WEAK CAP...HAS SUPPORTED CONVECTION ACROSS NORTHERN AND
EASTERN PORTIONS OF THE FORECAST AREA THIS MORNING AND THIS
AFTERNOON. SO FAR...STORMS HAVE LARGELY REMAINED BELOW SEVERE LIMITS
THROUGH THE MORNING...HOWEVER...WITH INCREASED HEATING THIS
AFTERNOON...STORMS HAVE INCREASED IN STRENGTH GIVEN THE DECENT
DEGREE OF BULK SHEAR. AS OF 3 PM CDT...UNDER PARTLY TO MOSTLY
CLOUDY SKIES...TEMPERATURES RANGED FROM 62 IN RAIN COOLED AIR AT
AINSWORTH...TO 90 AT IMPERIAL.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 318 PM CDT WED JUL 9 2014
TONIGHT AND THURSDAY...PRECIPITATION CHANCES TONIGHT
AND TOMORROW AFTERNOON ARE THE MAIN FORECAST CONCERNS. FOR
TONIGHT...THUNDERSTORM CHANCES WILL CONTINUE THROUGH LATE EVENING
AND MAY POSSIBLY CONTINUE INTO THE OVERNIGHT WITH THE PRESENCE OF A
LOW LEVEL JET ANCHORED ACROSS SOUTHERN NEBRASKA. ATTM CONFIDENCE IN
PCPN PERSISTING INTO THE OVERNIGHT IS NOT HIGH ATTM AS THE NAM SOLN
IS A TAD FARTHER EAST WITH ITS LOW LEVEL JET AND THE HRRR SOLN
PUSHES THIS ACTIVITY SOUTH OF THE AREA BY LATE EVENING. THURSDAY
MORNING WILL BE QUIET ACROSS WESTERN AND NORTH CENTRAL
NEBRASKA...HOWEVER...BY THURSDAY AFTERNOON...SURFACE HEATING AND THE
APPROACH OF AN UPPER LEVEL DISTURBANCE...WILL STEEPEN LAPSE RATES
ACROSS THE WESTERN FORECAST AREA BY 21Z THURSDAY. H85 TO H7 LAPSE
RATES WILL APPROACH 9.5 TO 10C THURSDAY AFTERNOON. IN ADDITION...THE
CAP WILL WEAKEN INVOF A SURFACE TROUGH MID AFTERNOON THURSDAY.
ATTM...THUNDERSTORMS ARE EXPECTED TO INITIATE MID AFTERNOON IN THE
PANHANDLE AND TRACK EAST. ATTM...WILL CONFINE PRECIP CHANCES TO THE
WESTERN HALF OF THE FORECAST AREA...AS LOCATIONS IN THE EAST ARE
STRONGLY CAPPED THURSDAY AFTERNOON.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 318 PM CDT WED JUL 9 2014
THURSDAY NIGHT THROUGH SATURDAY NIGHT...THE MAIN FORECASTING
CHALLENGE CONTINUES TO BE PRECIPITATION CHANCES AS THE FORECAST AREA
REMAINS IN NORTHWESTERLY AND WEST NORTHWESTERLY FLOW ALOFT. A
FRONTAL BOUNDARY WILL PUSH SOUTH ACROSS WESTERN AND NORTH CENTRAL
NEBRASKA THURSDAY NIGHT AND WILL BE THE FOCUS FOR SHOWER AND
THUNDERSTORM DEVELOPMENT THURSDAY NIGHT INTO FRIDAY MORNING. STRONG
STORMS WILL BE POSSIBLE INVOF THE FRONT THURSDAY EVENING...WITH 35
TO 45 KTS OF DEEP LAYER SHEAR THURSDAY EVENING. INTO THE OVERNIGHT
HOURS...A STRONG LOW LEVEL JET EXTENDING FROM SWRN NEBRASKA INTO
NERN NEBRASKA...WILL ALLOW THE THREAT FOR STORMS TO
CONTINUE...HOWEVER...THE THREAT FOR SEVERE STORMS WILL DIMINISH AS
DEEP LAYER SHEAR DECREASES TO 20 TO 30 KTS OVERNIGHT. ON
FRIDAY...THE FRONT WILL STALL EITHER IN SOUTHWESTERN KS TO SERN
NEBRASKA PER THE NAM SOLN OR FROM NWRN KS INTO SOUTH CENTRAL
NEBRASKA PER THE GFS SOLN. THE GFS GENERATES A NICE AREA OF POST
FRONTAL MID LEVEL LIFT NORTH OF THE FRONT ACROSS CENTRAL AND
NORTHERN NEBRASKA FRIDAY AFTERNOON INTO FRIDAY NIGHT...WHILE THIS IS
LARGELY ABSENT IN THE NAM SOLN. EVEN WITH A MODEL COMPROMISE AND THE
FRONT ACROSS NORTHERN KS...DECENT MID LEVEL LIFT AND WARM AIR
ADVECTION NORTH OF THE FRONT ACROSS THE FORECAST AREA PER THE GFS SOLN IS
HARD TO IGNORE. WITH THIS IN MIND...WILL CONTINUE POPS FRIDAY
AFTERNOON INTO FRIDAY NIGHT. ON SATURDAY...THE FRONT WILL WASH
OUT...ALLOWING SRLY WINDS TO SURGE NORTH INTO THE PANHANDLE. THETA E
RIDGING AND INCREASED MOISTURE WILL BUILD NORTH INTO THE PANHANDLE
AS WELL LEADING TO 1500 TO 2500 J/KG CAPES SATURDAY AFTERNOON.
THUNDERSTORMS SHOULD INITIATE QUICKLY LATE SAT AFTERNOON...WITHIN A
WEAKLY CAPPED AREA IN THE PANHANDLE AND WESTERN SANDHILLS. THIS
ACTIVITY WILL TRANSITION EAST SAT EVENING AND HAS THE POTENTIAL TO
BE SEVERE WITH FCST DEEP LAYER SHEAR OF 40 TO 50 KTS.
SUNDAY THROUGH WEDNESDAY...A STRONG UPPER LEVEL LOW OVER THE HUDSON
BAY WILL DROP SOUTH INTO WESTERN ONTARIO. THIS WILL FORCE A STRONG
NRN STREAM COLD FRONT INTO THE REGION SUNDAY AFTERNOON INTO SUNDAY
NIGHT. THUNDERSTORMS MAY DEVELOP ALONG AND BEHIND THIS FEATURE
SUNDAY AND SUNDAY NIGHT AND WILL SHIFT SOUTH BY MONDAY MORNING. HIGH
AMPLITUDE NORTHWESTERLY FLOW ALOFT WILL DEVELOP ACROSS THE HIGH
PLAINS MONDAY. ANY STORMS WHICH DO FIRE TO THE WEST UNDERNEATH THE
THETA E AXIS...SHOULD STAY MAINLY OFF TO THE WEST OF THE FORECAST
AREA GIVEN THE NWRLY STEERING WINDS. WITH THIS IN MIND...WILL KEEP
THE HIGHEST POPS IN THE PANHANDLE AND FAR SOUTHWEST. MUCH COOLER
TEMPERATURES WILL DEVELOP BEHIND THE FRONT WITH 70S FOR HIGHS
TUESDAY AND WEDNESDAY OF NEXT WEEK AND POPS GENERALLY CONFINED TO
THE HIGHER TERRAIN OF COLORADO AND SERN WYOMING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 232 AM CDT THU JUL 10 2014
IFR CEILING HAVE ENDED AT KLBF...WHICH WERE MOST LIKELY INDUCED BY
OUTFLOW WINDS FROM THUNDERSTORMS EAST OF THE TERMINAL. WILL NEED
TO MONITOR THE NEXT FEW HOURS HOWEVER.
VFR CONDITIONS SHOULD REVAIL UNTIL THE NEXT ROUND OF THUNDERSTORMS
INPACTS WESTERN NEBRASKA AFTER 21Z. HAVE INCLUDED A TEMPO FOR 5SM
TSRA AT KVTN FROM 23Z-03Z AND A PROB30 FOR KLBF FROM 01Z-05Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...CLB
AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1151 PM CDT WED JUL 9 2014
.SHORT TERM...(TONIGHT THROUGH SATURDAY)
ISSUED AT 319 PM CDT WED JUL 9 2014
MODELS IN RELATIVELY DECENT AGREEMENT LARGE SCALE FLOW OVER MOST OF
THE CONUS WILL BE NEAR ZONAL WHILE A POTENT SHORTWAVE TROF RUSHES
ACROSS CANADA. HEADING INTO THE WEEKEND THEN...PATTERN IS PROGGED TO
BEGIN AMPLIFYING WITH AN UPSTREAM RIDGE BECOMING ESTABLISHED OVER
THE WRN CONUS BY SAT AFTN. MEANWHILE...GULF MOISTURE ADVECTION WILL
BEGIN IN EARNEST LATER TONIGHT AS SFC HIGH PRESSURE SLIDES EAST AND
ALLOWS MOISTURE TO SLIDE UP ALONG THE WRN HIGH PLAINS. APPEARS THAT
MOISTURE RICH ENVIRONMENT WILL BE IN PLACE THEN THRU THE FCST PD.
CURRENT RADAR MOSAIC WAS SHOWING CLUSTER OF TSTMS FROM S-CNTRL SD
INTO N-CNTRL NEB MOVING SE WITHIN POCKET OF MID LYR ISENTROPIC
UPGLIDE. LATEST HRRR SUGGESTING AREA OF CONVECTION WILL GRADUALLY
INCREASE IN AREAL COVERAGE AND EXPAND INTO THE WRN CWA THEN EARLY
THIS EVENING AND POSSIBLY THE REST OF THE CWA OVERNIGHT.
OTHERWISE...MAIN ISSUE IS PINNING DOWN PLACEMENT/TIMING THUNDER POPS
THE NEXT COUPLE DAYS. HOWEVER...REASONABLE ASSUME ON THUR NIGHT/FRI
NIGHT...LLVL JET AND FAVORABLE FRONTOGENETIC FORCING/THETA-E CONVG
WITHIN BNDRY LYR WILL HELP INDUCE NOCTURNAL TSTM ACTIVITY. AS FOR
SVR TSTMS...NAM IS ADVERTISING POSSIBLE SVR DEVELOPMENT THUR NIGHT
OVER N-CNTRL NEB WITH MUCAPES 2000-2500 J/KG AND ADEQUATE VERTICAL
SHEAR. ALL THIS IN PART TO LEESIDE SFC LOW AND ATTENDANT THERMAL
BNDRY EXTENDING FROM ABOUT NERN CO TO NERN SD. GFS INSTABILITY/SHEAR
AT THAT TIME THOUGH IS SUBSTANTIALLY WEAKER.
NEVERTHELESS...SITUATION BEARS WATCHING.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 319 PM CDT WED JUL 9 2014
RATHER GOOD AGREEMENT BTWN CMC/ECM/GFS EARLY ON THAT AMPLIFICATION
WILL CONTINUE INTO EARLY NEXT WEEK WITH A HIGHLY ANOMALOUS UPPER
TROF OVER THE ERN CONUS AND UPSTREAM RIDGE OVER THE WRN CONUS. AT
THIS POINT DETERMINISTIC ECM/GFS AS WELL AS ECMENS/CMCENS ALL
INDICATE LARGE SCALE FLOW WILL BECOME STAGNANT AND ALLOW A RATHER
COOL AIRMASS FOR THIS TIME OF THE SEASON TO EXPAND SWD INTO THE
REGION DAY 6 AND 7. EXPECT THEN A GOOD CHUNK OF THE CNTRL PLAINS
WILL SEE WELL BELOW NORMAL AFTN TEMPS TUES AND WED. GOING POPS IN
THE EXT PDS LOOK GOOD FOR NOW SO NO MAJOR CHANGES PLANNED.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1150 PM CDT WED JUL 9 2014
POCKETS OF CONVECTION CONTINUE JUST WEST OF THE FORECAST AREA AT
05Z WITH KLNK STILL REPORTING OCCASIONAL SHOWERS. RAP STILL
INDICATES A GRADUAL EASTWARD SHIFT OF THE CENTRAL NEBRASKA SYSTEM
AS LOW LEVEL JET AND MOISTURE ADVECTION TRANSLATE INTO EASTERN
NEBRASKA BY 12Z AND CONTINUES THROUGH THE MORNING. HAVE LIMITED
A PERIOD OF CONVECTION AT KLNK DURING THE EARLY MORNING AND AT
KOMA AFTER 15Z. KOFK IS EXPECTED TO BE ON EDGE OF ACTIVITY THROUGH
THE PERIOD. LIMITED CONFIDENCE AT THIS TIME HOWEVER AND WILL NEED
TO MONITOR DEVELOPMENT TRENDS NEXT FEW HOURS TO SEE IF RAP IS
HEADING IN THE RIGHT DIRECTION WITH ITS SOLUTION.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...DEE
LONG TERM...DEE
AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
811 PM MDT FRI JUL 11 2014
.UPDATE...
ALLOWED THE FLASH FLOOD WATCH TO EXPIRE AT 8 PM MDT. TWEAKED POPS
A BIT FOR THE EVENING AND OVERNIGHT PERIODS. MAINLY ADJUSTED FAR
EASTERN EDGE TO LOWER OR REMOVE POPS. ZONES OUT SHORTLY. CHJ
&&
.PREV DISCUSSION...545 PM MDT FRI JUL 11 2014...
.AVIATION...
00Z TAF CYCLE
MAIN FOCUS FOR MONSOONAL SH/TS WILL BE FOUND OVER WESTERN AND
CENTRAL AREAS THROUGH EARLY-MID EVENING. APPEARS THAT WIDESPREAD
SH WOULD REMAIN ACROSS THE NORTHWEST THIRD OR SO DUE TO SOME
ADDITIONAL MID LEVEL FORCING THERE. DROPPED TS IMPACTS AFTER 2 TO
3Z AT FMN/GUP/ABQ/AEG AND SAF. THEN TRANSITION TO SH IMPACTS
THEREAFTER. GUP/FMN WOULD SEE THE LONGEST DURATION SH IMPACTS.
WATCHING LOW LEVEL CUMULUS FIELD PUSHING NORTHWESTWARD AHEAD OF AN
EASTERLY WAVE CURRENTLY OVER MEXICO. MVFR CIGS COULD IMPACT THE SE
PLAINS LATER THIS EVENING. CURRENTLY HAVE IMPACTS AT ROW AT THIS
TIME...GENERALLY AFTER 9Z. WILL MONITOR THAT TREND
ACCORDINGLY...WHETHER TCC NEEDS LOWER CIGS.
50
&&
.PREV DISCUSSION...328 PM MDT FRI JUL 11 2014...
.SYNOPSIS...
AN ACTIVE SHOWER AND THUNDERSTORM PERIOD IS ON TAP FOR THE NEXT
WEEK. SHOWERS AND THUNDERSTORMS WILL FAVOR WESTERN AND NORTHERN
NEW MEXICO FOR THE REST OF TODAY AND SATURDAY...BEFORE THE FOCUS
SHIFTS...OR PERHAPS JUST SPREADS...INTO EASTERN NEW MEXICO SUNDAY
THROUGH MUCH OF NEXT WEEK. SEVERAL BACK DOOR COLD FRONT NEXT WEEK
WILL BE A FOCUS FOR PRECIPITATION ACROSS THE PLAINS. THIS WILL
ALSO COOL TEMPERATURES BACK BELOW NORMAL. STORMS WILL MOVE SLOWLY
ALL WEEK...THUS THE POTENTIAL FOR FLOODING EXISTS DAILY...
ESPECIALLY OVER BURN SCARS.
&&
.DISCUSSION...
WATER VAPOR AND VIS SATELLITE IMAGERY SHOWING SUBSTANTIAL DRY AIR
AND SUBSIDENCE MOVING INTO MUCH OF EASTERN AND PORTIONS OF CENTRAL
NM AHEAD OF AN EASTERLY WAVE. MONSOONAL PLUME IS CERTAINLY FOCUSED
ACROSS WESTERN NM WHERE FLASH FLOOD WATCH IS IN PLACE AND PWATS ARE
AT OR JUST ABOVE NORMAL. APPEARS LIKE THE DRY AIR HAS PUSHED FURTHER
WEST THAN MODELS SUGGESTED...BUT THE 17Z HRRR APPEARS TO BE ON TRACK
WITH SHIFTING THE FOCUS FOR PRECIPITATION TONIGHT FURTHER TO THE
NORTHWEST...WHERE THETA-E RIDGE AXIS LIES. HAVE INCREASED POPS IN
THIS AREA AS THESE LOCALES HAVE RECEIVED PLENTY OF SUNSHINE
TODAY...AND WITH GOOD INSTABILITY AND STORM MOTIONS GENERALLY TOWARD
THE WEST...IT MAKES SENSE THAT STORMS FAVOR THAT AREA TONIGHT. THERE
IS ALSO A PRECARIOUS BOUNDARY RIGHT ALONG THE NE NM/SE CO BORDER
THAT HAS RECENTLY SPARKED AN ISOLATED STORM. LOOKS LIKE THIS
BOUNDARY WILL STAY NORTH OF THE AREA...THUS HAVE KEPT POPS AT A
MINIMUM. ABQ AREA WILL BE TRICKY...AS STORMS THUS FAR HAVE STRUGGLED
THAT HAVE FORMED ON THE SANDIAS DUE TO THE DRY AIR...BUT ADDITIONAL
STORMS HAVE DEVELOPED EAST OF THE MTNS AND BASED ON STORM
MOTIONS...SHOULD ARRIVE IN ABQ PRIOR TO 6PM IF THEY HOLD TOGETHER.
THE EASTERLY WAVE SLIDES SOUTH OF THE STATE TONIGHT. THERE WILL
STILL BE SOME DRY AIR IN PLACE OVER THE EAST TOMORROW...BUT THE UPPER
HIGH THAT IS OVER THE NE NOW...WILL START TO SHIFT WNW. THIS WILL
MEAN LITTLE CHANGE FOR STORM COVERAGE AND PLACEMENT FOR SATURDAY.
MOST STORMS WILL TRAVEL WESTWARD...EXCEPT STORMS ACROSS THE NE WHICH
MAY DRIFT EASTWARD. THESE NE STORMS WILL DEVELOP ALONG A WEAK COLD
FRONT THAT WILL GENERALLY STALL ACROSS THE AREA. OUTFLOW BOUNDARIES
LATER IN THE EVENING MAY PUSH IT FURTHER SOUTH HOWEVER.
THE WEAK FRONT ACROSS THE NE LOOKS TO BE REINFORCED A BIT ON
SUNDAY...AND THIS MAY PUSH THE FRONT FURTHER SOUTH. HAVE EXPANDED
CHANCE POPS ACROSS THE NE FOR THIS REASON. OTHERWISE...THE UPPER
HIGH WILL BE CENTERED ACROSS THE GREAT BASIN...WHICH GENERALLY TILTS
THE WEAK MONSOONAL PLUME OVER INTO MORE OF THE STATE.
WITH AN EXISTING BOUNDARY IN PLAY ACROSS THE EAST...HAVE INCREASED
POPS ACROSS THE PLAINS FOR MONDAY. THEN THE STRONGER
FRONT...ASSOCIATED WITH THE STRONG UPPER LOW ACROSS THE GREAT
LAKES...WILL ARRIVE MONDAY NIGHT AND TUESDAY...PUTTING ADDITIONAL
FOCUS FOR STORMS ACROSS THE EAST. THE WEST WILL REMAIN ACTIVE
TOO...ESPECIALLY IF THE FRONT PUSHES THRU THE GAPS.
NORTHWEST FLOW WILL BE IN PLACE OVER NM MID WEEK AS THE PATTERN
BECOMES QUITE AMPLIFIED. THIS IS NOT GOOD IN TERMS OF RECEIVING
MOISTURE FROM THE SOUTH...THE TRADITIONAL MONSOON WAY...BUT REGULAR
DISTURBANCES IN THE NORTHWEST FLOW WILL CONTINUE USHER IN MOISTURE
ACROSS THE EAST BEHIND BACK DOOR FRONTS...AND ONE SUCH STRONG FRONT
LOOKS TO ARRIVE WEDNESDAY NIGHT...WHICH MAY PUSH THRU THE GAPS OF
THE CENTRAL MTN CHAIN ONCE AGAIN. THUS...AN ACTIVE PATTERN WILL
PERSIST THRU THE NEXT WEEK. MODELS ARE HINTING AT REBUILDING THE
UPPER HIGH OVER NM NEXT WEEKEND. STAY TUNED.
34
&&
.FIRE WEATHER...
AN ACTIVE MONSOON MOISTURE PLUME WILL CONTINUE WITH WETTING RAIN
OVER THE WESTERN...CENTRAL AND NORTHERN CENTRAL ZONES THIS AFTERNOON
AND SATURDAY. AN EXPANSION IN THE WETTING RAIN PATTERN WILL COMMENCE
ON SUNDAY WHEN A BACK DOOR FRONT SUPPORTS INCREASED CHANCES OF
PRECIPITATION ACROSS NORTHEASTERN ZONES. A WIDESPREAD WET PATTERN
WILL THEN BE IN PLACE FOR THE WORK WEEK WITH INCREASED CHANCES OF
BURN SCAR FLOODING.
UPPER LEVEL HIGH CURRENTLY IS CENTERED OVER EXTREME EASTERN TEXAS
WITH AN EASTERLY WAVE CENTERED JUST SOUTH OF THE BIG BEND AREA AND
SLOWLY DRIFTING TO THE NORTHWEST. A BROAD AREA OF SUBSIDENCE AHEAD
OF THE WAVE IS USHERING IN MID LEVEL DRY AIR INTO EASTERN NEW
MEXICO...THUS SHUTTING DOWN WETTING RAIN ACROSS THE EASTERN ZONES.
SURFACE MOISTURE REMAINS IN PLACE ACROSS THE EAST WHERE SOME
EXCELLENT RH RECOVERIES ARE EXPECTED TONIGHT...WITH MAINLY GOOD
VALUES ELSEWHERE.
UPCOMING PATTERN CHANGES ARE CURRENTLY DEVELOPING WELL NORTH OF NEW
MEXICO AS AN UPPER RIDGE BUILDS OVER THE WEST COAST AND AN UPPER LOW
DEEPENS OVER CENTRAL CANADA. THIS PATTERN WILL AMPLIFY STARTING
SUNDAY AS THE HIGH CONTINUES TO STRENGTHEN AS THE LOW MOVES TOWARD
THE GREAT LAKES. THE FIRST OF SEVERAL BACK DOOR FRONTS WILL EDGE
INTO THE NORTHEAST ON SUNDAY...WITH COOLER TEMPERATURES...ENHANCED
LOW LEVEL MOISTURE AND INCREASED CHANCES OF WETTING RAIN FROM THE
NORTH CENTRAL MOUNTAIN TO THE NORTHEAST PLAINS. MONSOON PLUME WILL
PERSIST ACROSS THE WEST THUS ONLY THE EXTREME EAST CENTRAL PLAINS
LOOK TO REMAIN DRY.
FOR THE WORK WEEK...THE AMPLIFIED PATTERN PERSISTS WITH HIGH
PRESSURE TO THE WEST AND REGULAR WIND SHIFTS INTO THE NORTHEAST
MAINTAINING MOIST LOW LEVEL EAST TO SOUTHEAST FLOW ACROSS THE
EASTERN PLAINS THROUGH THE WORK WEEK. EXTEND MODELS SHOW REASONABLE
AGREEMENT WITH UPPER LEVEL DISTURBANCES IN THE NORTHWEST FLOW ALOFT
ON EARLY WEDNESDAY AND AGAIN ON THURSDAY. WHILE THERE IS STILL
UNCERTAINTY IN THE TIMING OF SPECIFIC FEATURES...THE CHANCES FOR
WIDESPREAD WETTING RAIN FOR THE WORK WEEK...RESULTING IN POSSIBLE BURN
SCAR FLOODING... ARE FAIRLY CERTAIN. OVERNIGHT RH RECOVERIES LOOK TO
BE GOOD TO EXCELLENT THROUGH THE WORK WEEK. PERIODS OF POOR TO FAIR
VENTILATION CAN BE EXPECTED...ESPECIALLY ACROSS THE NORTH ON
SUNDAY...PORTIONS OF THE WEST ON MONDAY AND TUESDAY...AND THE
NORTHEAST TO EAST WEDNESDAY INTO THURSDAY.
05
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
40
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
545 PM MDT FRI JUL 11 2014
.AVIATION...
00Z TAF CYCLE
MAIN FOCUS FOR MONSOONAL SH/TS WILL BE FOUND OVER WESTERN AND
CENTRAL AREAS THROUGH EARLY-MID EVENING. APPEARS THAT WIDESPREAD
SH WOULD REMAIN ACROSS THE NORTHWEST THIRD OR SO DUE TO SOME
ADDITIONAL MID LEVEL FORCING THERE. DROPPED TS IMPACTS AFTER 2 TO
3Z AT FMN/GUP/ABQ/AEG AND SAF. THEN TRANSITION TO SH IMPACTS
THEREAFTER. GUP/FMN WOULD SEE THE LONGEST DURATION SH IMPACTS.
WATCHING LOW LEVEL CUMULUS FIELD PUSHING NORTHWESTWARD AHEAD OF AN
EASTERLY WAVE CURRENTLY OVER MEXICO. MVFR CIGS COULD IMPACT THE SE
PLAINS LATER THIS EVENING. CURRENTLY HAVE IMPACTS AT ROW AT THIS
TIME...GENERALLY AFTER 9Z. WILL MONITOR THAT TREND
ACCORDINGLY...WHETHER TCC NEEDS LOWER CIGS.
50
&&
.PREV DISCUSSION...328 PM MDT FRI JUL 11 2014...
.SYNOPSIS...
AN ACTIVE SHOWER AND THUNDERSTORM PERIOD IS ON TAP FOR THE NEXT
WEEK. SHOWERS AND THUNDERSTORMS WILL FAVOR WESTERN AND NORTHERN
NEW MEXICO FOR THE REST OF TODAY AND SATURDAY...BEFORE THE FOCUS
SHIFTS...OR PERHAPS JUST SPREADS...INTO EASTERN NEW MEXICO SUNDAY
THROUGH MUCH OF NEXT WEEK. SEVERAL BACK DOOR COLD FRONT NEXT WEEK
WILL BE A FOCUS FOR PRECIPITATION ACROSS THE PLAINS. THIS WILL
ALSO COOL TEMPERATURES BACK BELOW NORMAL. STORMS WILL MOVE SLOWLY
ALL WEEK...THUS THE POTENTIAL FOR FLOODING EXISTS DAILY...
ESPECIALLY OVER BURN SCARS.
&&
.DISCUSSION...
WATER VAPOR AND VIS SATELLITE IMAGERY SHOWING SUBSTANTIAL DRY AIR
AND SUBSIDENCE MOVING INTO MUCH OF EASTERN AND PORTIONS OF CENTRAL
NM AHEAD OF AN EASTERLY WAVE. MONSOONAL PLUME IS CERTAINLY FOCUSED
ACROSS WESTERN NM WHERE FLASH FLOOD WATCH IS IN PLACE AND PWATS ARE
AT OR JUST ABOVE NORMAL. APPEARS LIKE THE DRY AIR HAS PUSHED FURTHER
WEST THAN MODELS SUGGESTED...BUT THE 17Z HRRR APPEARS TO BE ON TRACK
WITH SHIFTING THE FOCUS FOR PRECIPITATION TONIGHT FURTHER TO THE
NORTHWEST...WHERE THETA-E RIDGE AXIS LIES. HAVE INCREASED POPS IN
THIS AREA AS THESE LOCALES HAVE RECEIVED PLENTY OF SUNSHINE
TODAY...AND WITH GOOD INSTABILITY AND STORM MOTIONS GENERALLY TOWARD
THE WEST...IT MAKES SENSE THAT STORMS FAVOR THAT AREA TONIGHT. THERE
IS ALSO A PRECARIOUS BOUNDARY RIGHT ALONG THE NE NM/SE CO BORDER
THAT HAS RECENTLY SPARKED AN ISOLATED STORM. LOOKS LIKE THIS
BOUNDARY WILL STAY NORTH OF THE AREA...THUS HAVE KEPT POPS AT A
MINIMUM. ABQ AREA WILL BE TRICKY...AS STORMS THUS FAR HAVE STRUGGLED
THAT HAVE FORMED ON THE SANDIAS DUE TO THE DRY AIR...BUT ADDITIONAL
STORMS HAVE DEVELOPED EAST OF THE MTNS AND BASED ON STORM
MOTIONS...SHOULD ARRIVE IN ABQ PRIOR TO 6PM IF THEY HOLD TOGETHER.
THE EASTERLY WAVE SLIDES SOUTH OF THE STATE TONIGHT. THERE WILL
STILL BE SOME DRY AIR IN PLACE OVER THE EAST TOMORROW...BUT THE UPPER
HIGH THAT IS OVER THE NE NOW...WILL START TO SHIFT WNW. THIS WILL
MEAN LITTLE CHANGE FOR STORM COVERAGE AND PLACEMENT FOR SATURDAY.
MOST STORMS WILL TRAVEL WESTWARD...EXCEPT STORMS ACROSS THE NE WHICH
MAY DRIFT EASTWARD. THESE NE STORMS WILL DEVELOP ALONG A WEAK COLD
FRONT THAT WILL GENERALLY STALL ACROSS THE AREA. OUTFLOW BOUNDARIES
LATER IN THE EVENING MAY PUSH IT FURTHER SOUTH HOWEVER.
THE WEAK FRONT ACROSS THE NE LOOKS TO BE REINFORCED A BIT ON
SUNDAY...AND THIS MAY PUSH THE FRONT FURTHER SOUTH. HAVE EXPANDED
CHANCE POPS ACROSS THE NE FOR THIS REASON. OTHERWISE...THE UPPER
HIGH WILL BE CENTERED ACROSS THE GREAT BASIN...WHICH GENERALLY TILTS
THE WEAK MONSOONAL PLUME OVER INTO MORE OF THE STATE.
WITH AN EXISTING BOUNDARY IN PLAY ACROSS THE EAST...HAVE INCREASED
POPS ACROSS THE PLAINS FOR MONDAY. THEN THE STRONGER
FRONT...ASSOCIATED WITH THE STRONG UPPER LOW ACROSS THE GREAT
LAKES...WILL ARRIVE MONDAY NIGHT AND TUESDAY...PUTTING ADDITIONAL
FOCUS FOR STORMS ACROSS THE EAST. THE WEST WILL REMAIN ACTIVE
TOO...ESPECIALLY IF THE FRONT PUSHES THRU THE GAPS.
NORTHWEST FLOW WILL BE IN PLACE OVER NM MID WEEK AS THE PATTERN
BECOMES QUITE AMPLIFIED. THIS IS NOT GOOD IN TERMS OF RECEIVING
MOISTURE FROM THE SOUTH...THE TRADITIONAL MONSOON WAY...BUT REGULAR
DISTURBANCES IN THE NORTHWEST FLOW WILL CONTINUE USHER IN MOISTURE
ACROSS THE EAST BEHIND BACK DOOR FRONTS...AND ONE SUCH STRONG FRONT
LOOKS TO ARRIVE WEDNESDAY NIGHT...WHICH MAY PUSH THRU THE GAPS OF
THE CENTRAL MTN CHAIN ONCE AGAIN. THUS...AN ACTIVE PATTERN WILL
PERSIST THRU THE NEXT WEEK. MODELS ARE HINTING AT REBUILDING THE
UPPER HIGH OVER NM NEXT WEEKEND. STAY TUNED.
34
&&
.FIRE WEATHER...
AN ACTIVE MONSOON MOISTURE PLUME WILL CONTINUE WITH WETTING RAIN
OVER THE WESTERN...CENTRAL AND NORTHERN CENTRAL ZONES THIS AFTERNOON
AND SATURDAY. AN EXPANSION IN THE WETTING RAIN PATTERN WILL COMMENCE
ON SUNDAY WHEN A BACK DOOR FRONT SUPPORTS INCREASED CHANCES OF
PRECIPITATION ACROSS NORTHEASTERN ZONES. A WIDESPREAD WET PATTERN
WILL THEN BE IN PLACE FOR THE WORK WEEK WITH INCREASED CHANCES OF
BURN SCAR FLOODING.
UPPER LEVEL HIGH CURRENTLY IS CENTERED OVER EXTREME EASTERN TEXAS
WITH AN EASTERLY WAVE CENTERED JUST SOUTH OF THE BIG BEND AREA AND
SLOWLY DRIFTING TO THE NORTHWEST. A BROAD AREA OF SUBSIDENCE AHEAD
OF THE WAVE IS USHERING IN MID LEVEL DRY AIR INTO EASTERN NEW
MEXICO...THUS SHUTTING DOWN WETTING RAIN ACROSS THE EASTERN ZONES.
SURFACE MOISTURE REMAINS IN PLACE ACROSS THE EAST WHERE SOME
EXCELLENT RH RECOVERIES ARE EXPECTED TONIGHT...WITH MAINLY GOOD
VALUES ELSEWHERE.
UPCOMING PATTERN CHANGES ARE CURRENTLY DEVELOPING WELL NORTH OF NEW
MEXICO AS AN UPPER RIDGE BUILDS OVER THE WEST COAST AND AN UPPER LOW
DEEPENS OVER CENTRAL CANADA. THIS PATTERN WILL AMPLIFY STARTING
SUNDAY AS THE HIGH CONTINUES TO STRENGTHEN AS THE LOW MOVES TOWARD
THE GREAT LAKES. THE FIRST OF SEVERAL BACK DOOR FRONTS WILL EDGE
INTO THE NORTHEAST ON SUNDAY...WITH COOLER TEMPERATURES...ENHANCED
LOW LEVEL MOISTURE AND INCREASED CHANCES OF WETTING RAIN FROM THE
NORTH CENTRAL MOUNTAIN TO THE NORTHEAST PLAINS. MONSOON PLUME WILL
PERSIST ACROSS THE WEST THUS ONLY THE EXTREME EAST CENTRAL PLAINS
LOOK TO REMAIN DRY.
FOR THE WORK WEEK...THE AMPLIFIED PATTERN PERSISTS WITH HIGH
PRESSURE TO THE WEST AND REGULAR WIND SHIFTS INTO THE NORTHEAST
MAINTAINING MOIST LOW LEVEL EAST TO SOUTHEAST FLOW ACROSS THE
EASTERN PLAINS THROUGH THE WORK WEEK. EXTEND MODELS SHOW REASONABLE
AGREEMENT WITH UPPER LEVEL DISTURBANCES IN THE NORTHWEST FLOW ALOFT
ON EARLY WEDNESDAY AND AGAIN ON THURSDAY. WHILE THERE IS STILL
UNCERTAINTY IN THE TIMING OF SPECIFIC FEATURES...THE CHANCES FOR
WIDESPREAD WETTING RAIN FOR THE WORK WEEK...RESULTING IN POSSIBLE BURN
SCAR FLOODING... ARE FAIRLY CERTAIN. OVERNIGHT RH RECOVERIES LOOK TO
BE GOOD TO EXCELLENT THROUGH THE WORK WEEK. PERIODS OF POOR TO FAIR
VENTILATION CAN BE EXPECTED...ESPECIALLY ACROSS THE NORTH ON
SUNDAY...PORTIONS OF THE WEST ON MONDAY AND TUESDAY...AND THE
NORTHEAST TO EAST WEDNESDAY INTO THURSDAY.
05
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 8 PM MDT THIS EVENING FOR THE FOLLOWING
ZONES...NMZ504-506>508-511.
&&
$$
AREA FORECAST DISCUSSION
NWS RALEIGH NC
317 AM EDT THU JUL 10 2014
.SYNOPSIS...A WEAKENING COLD FRONT WILL MOVE INTO THE AREA TODAY
THEN DRIFT TOWARD THE COAST FRIDAY. WEAK HIGH PRESSURE WILL SETTLE
OVER THE REGION SATURDAY.
&&
.NEAR TERM /OVERNIGHT/...
AS OF 1045 PM WEDNESDAY...
CYCLONIC FLOW ALOFT WILL PREVAIL ACROSS THE REGION OVERNIGHT...
FOSTERING A POTENTIAL FOR DPVA ASSOCIATED WITH SMALL AMPLITUDE
DISTURBANCES TRACKING EAST FROM THE TN/OH VALLEY INTO THE MID-
ATLANTIC AND NORTH CAROLINA. GIVEN THE PRESENCE OF MARGINAL
NOCTURNAL INSTABILITY (500-1000 J/KG MUCAPE) AND THE PRESENCE OF A
SHORTWAVE JUST UPSTREAM OVER TN/KY (PER RAP DATA AND WV IMAGERY)...
WILL CONTINUE TO INDICATE A SLIGHT CHANCE OF SHOWERS/STORMS
THROUGHOUT THE NIGHT. EXPECT LOWS IN THE LOWER 70S. -VINCENT
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 230 PM WEDNESDAY...
SCATTERED SHOWERS AND THUNDERSTORMS WILL OCCUR AGAIN ON THURSDAY AS
A SERIES OF WEAK DISTURBANCES MOVE NE ACROSS OUR AREA IN ADVANCE OF
THE MID-LEVEL TROUGH AXIS TO OUR WEST. AT THE SFC...THE COLD FRONT
CURRENTLY TO OUR NW WILL DROP SOUTH AND MERGE WITH THE PIEDMONT
TROUGH...PROVIDING A LOW LEVEL FOCUS FOR CONVECTION INITIATION.
NOTED THAT GUIDANCE SHOWS AN AXIS OF HIGH PWAT (AROUND 2 INCHES)
WILL PERSIST ACROSS THE EASTERN 2/3 OF OUR CWA DURING THE AFTERNOON
INTO THE EVENING...TRENDING LOWER TO AROUND 1.5 INCHES ACROSS THE
TRIAD. MEANWHILE...DEEP LAYER SHEAR WILL BE SIMILAR TO TODAY...25KT
OR LESS. THUS...WHILE WE CAN`T RULE OUT THE POTENTIAL FOR AN
ISOLATED STRONG WIND GUST OR TWO...THE MAIN IMPACTS MAY INSTEAD BE
HEAVY RAIN INVOF OF THE BELT OF HIGH PWAT...AND THE POTENTIAL FOR
LOCALIZED POOR DRAINAGE FLOODING WITH ANY OF THE SLOWER CELLS OR
LOCATIONS THAT SEE REPETITIVE DOWNPOURS. GIVEN THIS MOISTURE
PROFILE...LOOK FOR THE BEST COVERAGE AND THUS HIGHEST POPS TO BE
EAST OF THE TRIAD. SIMILAR TO TODAY...HIGHS WILL BE DEPENDENT ON
CLOUD COVERAGE...WHICH MAY BE MORE WIDESPREAD ACROSS OUR CWA TOMORROW
COMPARED TO TODAY. HIGHS IN THE MID-UPR 80S AND LOWS THURSDAY NIGHT
IN THE UPPER 60S TO AROUND 70.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 310 AM THURSDAY...
SATURDAY THROUGH SUNDAY NIGHT: THE WEAK MID LEVEL TROUGH AXIS IS
PROGGED TO PUSH TO THE EAST AND SOUTH OF CENTRAL NC BY SATURDAY
MORNING. AT THE SURFACE THE LINGERING WEAK SURFACE TROUGH ACROSS
EASTERN NC IS EXPECTED TO SLOWLY RETROGRADE WESTWARD ACROSS THE
PIEDMONT (REMAINING VERY WEAK)... AS THE MID LEVEL RIDGE OVER THE
SOUTHERN PLAINS AND INTERMOUNTAIN WEST IS EXPECTED TO NUDGE EASTWARD
AND INTO OUR AREA. THIS COUPLED WITH DRIER AIR BEHIND THE DEPARTING
MID LEVEL TROUGH AND LACK OF A GOOD TRIGGER WILL LEAD TO GENERALLY
ISOLATED CONVECTION ON SATURDAY... WITH THE BEST CHANCE ACROSS OUR
FAR EAST/SOUTHEAST (BEST REMAINING MOISTURE AND WEAK CONVERGENCE
EARLY IN THE AFTERNOON). WITH AFTERNOON LOW LEVEL THICKNESS VALUES
EXPECTED TO BE AROUND 1420 METERS AND LACK OF GOOD CONVECTIVE
COVERAGE THINK WE WILL SEE TEMPS AT LEAST CLIMB INTO THE UPPER
80S/NEAR 90 NORTH/NORTHWEST TO THE LOWER 90S SOUTH. EXPECT GENERALLY
DRY CONDITIONS OVERNIGHT. HOWEVER... WITH CENTRAL NC ON THE
PERIPHERY OF THE MID LEVELE RIDGE AND MOISTURE EXPECTED TO BE
INCREASE CANNOT COMPLETELY RULE OUT A WEAK PERTURBATION MOVING
THROUGH THE MID LEVEL FLOW AND SETTING OFF A FEW ISOLATED
SHOWERS/STORMS. EXPECT LOWS SUNDAY MORNING WILL BE IN THE UPPER 60S
TO LOWER 70S.
CHANCES FOR SHOWERS AND STORMS WILL INCREASE A BIT ON SUNDAY...
ALTHOUGH STILL LOW CHANCE/SLIGHT CHANCE POPS AT THIS TIME. EXPECT WE
WILL BEGIN TO SEE A FULL LATITUDE EASTERN U.S. TROUGH DEVELOP. WHILE
THE MID LEVEL RIDGE WILL GENERALLY HOLD ACROSS OUR AREA ON SUNDAY...
WE WILL SEE THE MID LEVEL RIDGE CENTER BEGIN TO RETREAT WESTWARD AND
SETUP ACROSS THE WESTERN U.S. THIS COUPLED WITH INCREASING MOISTURE
THROUGHOUT THE COLUMN AND A SHARPENING SURFACE TROUGH WILL LEAD TO A
LITTLE BIT BETTER CHANCE OF SHOWERS AND STORMS FOR SUNDAY
AFTERNOON/EVENING... WITH THE BEST CHANCES ACROSS THE
NORTH/NORTHWEST PIEDMONT. AFTERNOON LOW LEVEL THICKNESS VALUES ARE
EXPECTED TO RISE BY ANOTHER 5 TO 10 METERS OVER SATURDAY AFTERNOON.
THUS... EXPECT WE WILL SEE HIGH TEMPS IN THE LOWER TO MID 90S (MAYBE
EVEN A FEW UPPER 90S ACROSS THE SANDHILLS). LOWS MONDAY MORNING ARE
EXPECTED TO BE GENERALLY IN THE LOWER 70S.
MONDAY THROUGH WEDNESDAY: A DEEP TROUGH IS EXPECTED TO DEVELOP
ACROSS THE EASTERN HALF OF THE COUNTRY EARLY NEXT WEEK... WITH A
DEEP VORTEX EXPECTED TO DIVE SOUTHWARD OUT OF CANADA AND ACROSS THE
NORTHERN PLAINS/UPPER MIDWEST AND GREAT LAKES REGION. THIS SHOULD
RESULT IN THE INCREASING LIKELIHOOD OF SHOWERS AND STORMS EARLY NEXT
WEEK ACROSS CENTRAL NC.... AS A STRONG COLD FRONT MOVES INTO THE
AREA EARLY NEXT WEEK (LOOKING LIKE LATE TUESDAY INTO TUESDAY NIGHT
OR EARLY WEDNESDAY). THUS... WILL SHOW CHANCES FOR SHOWERS AND
STORMS INCREASING EARLY NEXT WEEK... PEAKING ON TUESDAY
AFTERNOON/EVENING. WITH MODELS NOW SHOWING THE FRONT PUSHING TO THE
SOUTH OF THE AREA ON WEDNESDAY WILL LOWER POPS... BUT STILL KEEPING
AT LEAST A SLIGHT CHANCE NORTH TO CHANCE SOUTH MENTIONED AS WE ARE
TALKING ABOUT DAY 7 OF THE FORECAST AND DEALING WITH AN ANOMALOUS
SETUP FOR THIS TIME OF YEAR. IN FACT WE COULD EVEN SEE MORE OF AN
ORGANIZED SEVERE THREAT AS MID LEVEL FLOW IS EXPECTED TO STRENGTHEN
AS THE SYSTEM APPROACHES. HIGH TEMPS AHEAD OF THE FRONT MAY BE
SUPPRESSED SOME BY CONVECTION... BUT STILL THINK LOWER TO MID 90S
WILL STILL BE POSSIBLE ON MONDAY AND POSSIBLY TUESDAY (MAYBE A
CATEGORY COOLER ON TUESDAY DEPENDING ON TIMING OF THE PRECIP/FRONT).
HIGHS TEMPS WEDNESDAY WILL BE COOLER IF THE FRONT INDEED PUSHES
THROUGH THE AREA. FOR NOW WILL GO WITH HIGHS IN THE MID TO UPPER
80S. LOWS EARLY TO MID NEXT WEEK ARE EXPECTED TO BE IN THE LOWER TO
MID 70S IN ADVANCE OF THE FRONT AND UPPER 60S TO LOWER 70S ON
WEDNESDAY MORNING.
&&
AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 105 AM THURSDAY...
A MOIST AND UNSTABLE AIR MASS WILL SUPPORT THE DEVELOPMENT OF
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS OVERNIGHT THROUGH
THURSDAY NIGHT AS AN UPPER LEVEL TROUGH AND ATTENDANT SURFACE
BOUNDARY MOVES ACROSS THE AREA. THE SHOWERS AND STORMS WILL BE MOST
NUMEROUS DURING THE AFTERNOON AND EARLY EVENING HOURS. EXPECT
MVFR/IFR VISIBILITIES AND CEILINGS IN VICINITY OF THE HEAVIER
SHOWERS AND STORMS. AWAY FROM THE CONVECTION...EXPECT VFR CONDITIONS
WITH SFC WINDS PREDOMINATELY WEST-SOUTHWEST AT LESS THAN 10 KTS.
IMPROVING AVIATION CONDITIONS ANTICIPATED FRIDAY THROUGH SATURDAY AS
A SLIGHTLY DRIER MORE STABLE AIR MASS COVERS MOST OF THE REGION.
SCATTERED AFTERNOON-EARLY EVENING CONVECTION WILL STILL BE PROBABLE
IN VICINITY OF KFAY AND KRWI FRIDAY WHERE AVAILABLE MOISTURE AND LOW
LEVEL INSTABILITY WILL BE BEST COMPARED TO THE PIEDMONT. ANY
CONVECTION SATURDAY IS EXPECTED TO BE ISOLATED. BY SUNDAY AND MONDAY
...REMNANTS OF DECAYING THUNDERSTORM COMPLEXES ORIGINATING IN THE
MIDWEST MAY BEGIN TO AFFECT CENTRAL NC...LEADING TO A SLIGHTLY
BETTER CHANCE FOR SCATTERED CONVECTION AND ASSOCIATED MVFR
CONDITIONS.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...VINCENT
SHORT TERM...NP
LONG TERM...BSD
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
105 AM EDT THU JUL 10 2014
.SYNOPSIS...A WEAKENING COLD FRONT WILL MOVE INTO THE AREA TODAY
THEN DRIFT TOWARD THE COAST FRIDAY. WEAK HIGH PRESSURE WILL SETTLE
OVER THE REGION SATURDAY.
&&
.NEAR TERM /OVERNIGHT/...
AS OF 1045 PM WEDNESDAY...
CYCLONIC FLOW ALOFT WILL PREVAIL ACROSS THE REGION OVERNIGHT...
FOSTERING A POTENTIAL FOR DPVA ASSOCIATED WITH SMALL AMPLITUDE
DISTURBANCES TRACKING EAST FROM THE TN/OH VALLEY INTO THE MID-
ATLANTIC AND NORTH CAROLINA. GIVEN THE PRESENCE OF MARGINAL
NOCTURNAL INSTABILITY (500-1000 J/KG MUCAPE) AND THE PRESENCE OF A
SHORTWAVE JUST UPSTREAM OVER TN/KY (PER RAP DATA AND WV IMAGERY)...
WILL CONTINUE TO INDICATE A SLIGHT CHANCE OF SHOWERS/STORMS
THROUGHOUT THE NIGHT. EXPECT LOWS IN THE LOWER 70S. -VINCENT
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
AS OF 230 PM WEDNESDAY...
SCATTERED SHOWERS AND THUNDERSTORMS WILL OCCUR AGAIN ON THURSDAY AS
A SERIES OF WEAK DISTURBANCES MOVE NE ACROSS OUR AREA IN ADVANCE OF
THE MID-LEVEL TROUGH AXIS TO OUR WEST. AT THE SFC...THE COLD FRONT
CURRENTLY TO OUR NW WILL DROP SOUTH AND MERGE WITH THE PIEDMONT
TROUGH...PROVIDING A LOW LEVEL FOCUS FOR CONVECTION INITIATION.
NOTED THAT GUIDANCE SHOWS AN AXIS OF HIGH PWAT (AROUND 2 INCHES)
WILL PERSIST ACROSS THE EASTERN 2/3 OF OUR CWA DURING THE AFTERNOON
INTO THE EVENING...TRENDING LOWER TO AROUND 1.5 INCHES ACROSS THE
TRIAD. MEANWHILE...DEEP LAYER SHEAR WILL BE SIMILAR TO TODAY...25KT
OR LESS. THUS...WHILE WE CAN`T RULE OUT THE POTENTIAL FOR AN
ISOLATED STRONG WIND GUST OR TWO...THE MAIN IMPACTS MAY INSTEAD BE
HEAVY RAIN INVOF OF THE BELT OF HIGH PWAT...AND THE POTENTIAL FOR
LOCALIZED POOR DRAINAGE FLOODING WITH ANY OF THE SLOWER CELLS OR
LOCATIONS THAT SEE REPETITIVE DOWNPOURS. GIVEN THIS MOISTURE
PROFILE...LOOK FOR THE BEST COVERAGE AND THUS HIGHEST POPS TO BE
EAST OF THE TRIAD. SIMILAR TO TODAY...HIGHS WILL BE DEPENDENT ON
CLOUD COVERAGE...WHICH MAY BE MORE WIDESPREAD ACROSS OUR CWA TOMORROW
COMPARED TO TODAY. HIGHS IN THE MID-UPR 80S AND LOWS THURSDAY NIGHT
IN THE UPPER 60S TO AROUND 70.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 245 PM WEDNESDAY...
FOR FRI THROUGH SAT NIGHT: THE WEAKENING MID LEVEL TROUGH AXIS
SHIFTS EAST OF THE SRN APPALACHIANS FRI... BEFORE SWEEPING OVERHEAD
FRI NIGHT AND TO OUR EAST SAT. THE WEAK SURFACE TROUGH WILL ROUGHLY
FOLLOW THIS PACE AS WELL... SETTLING OVER THE COASTAL CAROLINAS BY
SAT MORNING BEFORE LARGELY DISSIPATING. THE EASTERN HALF OF NC WILL
REMAIN WITHIN SUFFICIENTLY DEEP MOISTURE FRI FOR MAINLY
AFTERNOON/EVENING SHOWERS AND STORMS... WHILE A DRIER COLUMN...
SLIGHT RISE IN HEIGHTS ALOFT... AND DOWNSLOPE LOW LEVEL FLOW OVER
THE WEST WILL LIMIT CONVECTION THERE... A PATTERN SUPPORTED BY THE
LATEST SREF PROBABILITIES OF CONVECTIVE PRECIP. THE GFS SHOWS MUCAPE
PEAKING AT 1500-2000 J/KG BUT SUBPAR DEEP LAYER SHEAR OF JUST AROUND
20 KTS OR SO... SO EXPECT ANOTHER ROUND OF WEAKLY FORCED AND SLOW
MOVING MULTICELL CLUSTER WITH SUPPRESSED SEVERITY BUT THE POTENTIAL
FOR TRAINING CELLS AND LOCALLY HEAVY RAIN GIVEN THE PW HOLDING NEAR
2.0 INCHES EAST OF HIGHWAY 1. THE SHEAR AXIS BROADENS AND WEAKENS
FURTHER ON SAT WITH MINOR RISES IN HEIGHTS ALOFT. ANY TRACE OF THE
SURFACE TROUGH IS TOUGH TO DETECT ON THE MODEL OUTPUT WITH A FAIRLY
UNIFORM LIGHT LOW LEVEL FLOW FROM THE S AND SE. MODELS SHOW CENTRAL
AND WRN NC WITHIN A RELATIVE PW MINIMUM... BETWEEN THE 1.5+ INCH
VALUES OVER COASTAL NC AND ERN SC... AND THE HIGHER VALUES PUSHING
INTO THE OH VALLEY ASSOCIATED WITH WHAT WILL LIKELY BE AN MCS
CROSSING THE MIDWEST AND SOUTHERN END OF THE GREAT LAKES SAT/SAT
NIGHT. BUT ANY AMOUNT OF ATLANTIC-SOURCE LOW LEVEL INFLOW COMBINED
WITH HEATING COULD GENERATE DISORGANIZED ISOLATED TO SCATTERED PULSE
CONVECTION IN THE AFTERNOON. WILL HAVE POPS ON THE LOW END... 20-30%
ORIENTED NW TO SE RESPECTIVELY...SAT AFTERNOON/EVENING. THICKNESSES
BOTH FRI AND SAT STAY SLIGHTLY BELOW NORMAL...WITH A BIT MORE
SUNSHINE ANTICIPATED SAT THAN FRI... SO WILL HOLD ONTO HIGHS FROM
THE MID 80S TO NEAR 90 WITH LOWS IN THE UPPER 60S TO LOWER 70S.
FOR SUN-WED: DEEP LAYER WIND FIELDS REMAIN VERY WEAK SUNDAY WITH
ONLY A SUBTLE SURFACE TROUGH EVIDENT THROUGH THE PIEDMONT... HOWEVER
WE WILL START TO SEE PW VALUES RECOVER BACK UP ABOVE SEASONAL
NORMALS... SUGGESTING A TREND BACK TO MORE SEASONALLY TYPICAL
COVERAGE OF AFTERNOON PULSE CONVECTION FOR SUNDAY. AN ANOMALOUSLY
STRONG MID LEVEL VORTEX (MID LEVEL HEIGHTS AS LOW S 2-3 STANDARD
DEVIATIONS BELOW NORMAL) AS LOW AS WILL WOBBLE EASTWARD ACROSS SRN
ONTARIO AND THE NRN GREAT LAKES SUN-TUE THEN INTO QUEBEC WED... AND
THIS BROAD TROUGHING OVER ERN NOAM WILL MEAN INCREASINGLY UNSETTLED
WEATHER FOR NC... WITH SW LOW LEVEL AHEAD OF THE SLOWLY APPROACHING
SURFACE COLD FRONT... AND STRENGTHENING MID LEVEL WESTERLY FLOW
FOSTERING BETTER STORM ORGANIZATION. WILL PLACE GOOD CHANCES OF
SHOWERS AND STORMS FOCUSED ON EACH AFTERNOON/EVENING MON-TUE... WITH
PERHAPS A SOUTHEASTWARD SHIFT OF THE HIGHER POPS WED TO LEVERAGE THE
POSSIBILITY THAT THE SURFACE FRONT MIGHT DROP SE INTO THE CWA AND
PUSH THE BETTER MOISTURE INTO SRN/ERN NC. SEE NOTHING TO INDICATE A
MAJOR DEPARTURE FROM CLIMATOLOGICAL TEMPS... AS GREATER-THAN-USUAL
CLOUD COVER WITH HEATING EACH DAY WILL MODULATE SLIGHTLY ABOVE-
NORMAL THICKNESSES... SO WILL STICK WITH DAILY HIGHS IN THE UPPER
80S TO LOWER 90S... AND DAILY LOWS NEAR 70 TO THE LOWER 70S. -GIH
&&
AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 105 AM THURSDAY...
A MOIST AND UNSTABLE AIR MASS WILL SUPPORT THE DEVELOPMENT OF
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS OVERNIGHT THROUGH
THURSDAY NIGHT AS AN UPPER LEVEL TROUGH AND ATTENDANT SURFACE
BOUNDARY MOVES ACROSS THE AREA. THE SHOWERS AND STORMS WILL BE MOST
NUMEROUS DURING THE AFTERNOON AND EARLY EVENING HOURS. EXPECT
MVFR/IFR VISIBILITIES AND CEILINGS IN VICINITY OF THE HEAVIER
SHOWERS AND STORMS. AWAY FROM THE CONVECTION...EXPECT VFR CONDITIONS
WITH SFC WINDS PREDOMINATELY WEST-SOUTHWEST AT LESS THAN 10 KTS.
IMPROVING AVIATION CONDITIONS ANTICIPATED FRIDAY THROUGH SATURDAY AS
A SLIGHTLY DRIER MORE STABLE AIR MASS COVERS MOST OF THE REGION.
SCATTERED AFTERNOON-EARLY EVENING CONVECTION WILL STILL BE PROBABLE
IN VICINITY OF KFAY AND KRWI FRIDAY WHERE AVAILABLE MOISTURE AND LOW
LEVEL INSTABILITY WILL BE BEST COMPARED TO THE PIEDMONT. ANY
CONVECTION SATURDAY IS EXPECTED TO BE ISOLATED. BY SUNDAY AND MONDAY
...REMNANTS OF DECAYING THUNDERSTORM COMPLEXES ORIGINATING IN THE
MIDWEST MAY BEGIN TO AFFECT CENTRAL NC...LEADING TO A SLIGHTLY
BETTER CHANCE FOR SCATTERED CONVECTION AND ASSOCIATED MVFR
CONDITIONS.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...VINCENT
SHORT TERM...NP
LONG TERM...HARTFIELD
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
120 AM EDT THU JUL 10 2014
.SYNOPSIS...
HIGH PRESSURE OVER THE UPPER MIDWEST WILL MOVE EAST ACROSS THE
GREAT LAKES ON THURSDAY AND BE LOCATED NEAR NEW YORK CITY BY
SATURDAY MORNING. A WARM FRONT WILL BE MOVING NORTHEAST FROM THE
LOWER OHIO VALLEY ON SATURDAY AS A COLD FRONT DROPS ACROSS THE
WESTERN GREAT LAKES. THE TWO FRONTS WILL CONVERGE ON THE AREA ON
SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
SOME SHOWERS DEVELOPING ON THE LAKE. UPDATED THE GRIDS TO REFLECT
THIS. SOME THUNDER IS ALSO POSSIBLE. AT THIS TIME EXPECTING IT TO
STAY OVER THE WATER...THIS WILL HAVE TO BE WATCHED.
COLD FRONT CONTINUING TO SAG SOUTH OF THE AREA THIS EVENING.
SHOWERS ON THE DECREASE. SOME TROFINESS AND RIGHT REAR QUAD OF THE
JET MAY KEEP SOME ISOLATED SHOWERS GOING TO AROUND MIDNIGHT MAINLY
OVER THE SOUTHERN PORTION OF THE FORECAST AREA. SKIES WILL BE
MOSTLY CLEAR TO PARTLY CLOUDY OVERNIGHT. THE MODELS HAVE PLENTY OF
LOW LEVEL MOISTURE AROUND AND WITH THE UPPER TROF ACROSS THE AREA
SOME CLOUDINESS WILL LINGER. THE HRRR MODEL TRIES TO DEVELOP SOME
SHOWERS OVER THE LAKE TOWARD DAYBREAK. THIS MAY OCCUR BECAUSE OF
THE WARM LAKE AND SOME CONVERGENCE. MADE ONLY MINOR ADJUSTMENTS TO
THE LOWS. IF THE CLOUDS STAY PATCHY TEMPERATURES SHOULD CONTINUE
TO DROP WITH THE LIGHT WINDS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY NIGHT/...
SOME OF THE MODELS SHOW ONE LAST SHORT WAVE SLIDING THROUGH THE
TROUGH ON THURSDAY MORNING. I SUPPOSE A SHOWER COULD SNEAK OFF THE
LAKE ACROSS EXTREME NE OH/NW PA IN THE MORNING OR MIDDAY OTHERWISE
THE DRY AIR AND SUBSIDENCE SHOULD WIN OUT. HIGHS IN THE 70S AGAIN.
SUNNY FRIDAY WITH PERHAPS A FEW HIGH CLOUDS AND PERHAPS A FEW
CUMULUS ACROSS NE OH/NW PA. HIGHS GENERALLY MID 70S TO LOWER 80S.
MOST OF THE MODELS ARE HOLDING OFF ON THE SHOWERS FOR SATURDAY WHICH
SEEMS REASONABLE AS THE SURFACE HIGH WILL JUST BE TO THE EAST AND
THERE SHOULD BE PLENTY OF DRY AIR IN THE LOWER LAYERS. CANNOT RULE
OUT A WARM ADVECTION SHOWER GETTING INTO NW OHIO. DEWPOINTS WILL
START TO INCREASE BUT WILL LIKELY NOT GET INTO THE UNCOMFORTABLE
RANGE YET. TEMPS SHOULD RECOVER TO NEAR NORMAL.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
MOST OF THE MODELS SHOW A SWATCH OF SHOWERS AND THUNDERSTORMS
SPILLING ACROSS THE LOWER GREAT LAKES SATURDAY NIGHT AND
ESPECIALLY ON SUNDAY AS A WARM FRONT PUSHES NORTH AND A COLD FRONT
SAGS SOUTHEAST ACROSS THE GREAT LAKES. WE MAY NEED TO GO WITH
HIGHER POPS BUT STILL NOT OVERLY CONFIDENT ABOUT THE TIMING. IF
THERE IS A THUNDERSTORM COMPLEX AND IT MISSES THE AREA OR MOVES
ACROSS THE AREA VERY QUICKLY THEN WE END UP WITH JUST A FEW
SHOWERS. WILL JUST KEEP IT A CHANCE FOR NOW. SHOULD BE MORE HUMID
BY SUNDAY BUT TEMPS ARE A LITTLE TRICKY DEPENDING ON THE AMOUNT
OF CLOUDS AND SHOWERS. WILL SPLIT THE DIFFERENCE AND GO FOR HIGHS
AROUND 80. COULD REACH THE LOWER/MID 80S WITH SOME SUNSHINE AND IT
COULD STAY IN THE 70S WITH ENOUGH CLOUDS AND SHOWERS.
UNSEASONABLY COOL AIR MASS FOR EARLY NEXT WEEK AS A PROMINENT TROUGH
REMAINS NEARLY STATIONARY ACROSS THE GREAT LAKES. COLD FRONT COMES
ACROSS MONDAY WITH SHOWERS/THUNDERSTORMS. THERE MAY BE SHOWERS THAT
POP UP WITH SECONDARY TROUGHS TUESDAY AND WEDNESDAY...BUT QUESTION
WILL BE HOW MUCH MOISTURE WILL BE AROUND. IF H8 TEMPS GET BELOW 8C
OR SO AND WINDS SHIFT OUT OF THE NORTHWEST THE LAKE MAY HELP WITH
THAT MOISTURE. TEMPERATURES WILL BE BELOW NORMAL AND BY MID WEEK
TEMPS WILL BE ON EITHER SIDE OF 70 FOR HIGHS.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
THE SHOWERS OVER WESTERN LAKE ERIE CONTINUE TO SLOWLY DIMINISH AND
EXPECT DRY WEATHER AT ALL OF THE TAFS. SOME PATCHES OF MID LEVEL
CLOUDS WILL AFFECT KCLE AND KERI OVERNIGHT. ALSO EXPECTING SOME
FAIR WEATHER CUMULUS DURING THE DAY. A FEW HOURS OF BKN CIGS ARE
POSSIBLE ACROSS NE OH AND NW PA AROUND MIDDAY. LIGHT AND VARIABLE
FLOW WILL BECOME N TO NE AFTER DAYBREAK. SPEEDS WILL BE UNDER 10
KNOTS THE ENTIRE PERIOD.
OUTLOOK...NON VFR AGAIN POSSIBLE LATE FRIDAY NIGHT THROUGH SUNDAY
IN THUNDERSTORMS.
&&
.MARINE...
ONE LAST TROUGH TO CROSS THE LAKE EARLY THIS EVENING THEN HIGH
PRESSURE MOVES OVERHEAD FOR THURSDAY. SO LIGHT WEST-NORTHWEST WINDS
WILL BECOME LIGHT/VARIABLE TONIGHT. THE HIGH SHIFTS EAST FRIDAY AND
A LIGHT SOUTHERLY FLOW RESULTS. SHOWERS/THUNDERSTORMS ENTER THE
FORECAST SATURDAY NIGHT AND SUNDAY AS THE ATMOSPHERE BECOMES MORE
UNSTABLE AHEAD OF THE NEXT SYSTEM. THE COLD FRONT WILL CROSS THE
LAKE ON MONDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KOSARIK
NEAR TERM...KIELTYKA
SHORT TERM...KOSARIK
LONG TERM...KOSARIK/OUDEMAN
AVIATION...KUBINA
MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS TULSA OK
1148 PM CDT WED JUL 9 2014
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
SHOWERS AND THUNDERSTORMS ACROSS KS CONTINUE TO DROP
SOUTHEAST LATE THIS EVENING. THIS ACTIVITY SHOULD BEGIN
TO IMPACT THE KBVO/KTUL AND KRVS TAF SITES AROUND 09-11Z
AND THE REMAINDER OF THE TAF SITES AFTER 14Z. BRIEF MVFR
CIGS/VSBYS WILL BE POSSIBLE IN THE STORMS.
&&
.PREV DISCUSSION... /ISSUED 952 PM CDT WED JUL 9 2014/
DISCUSSION...
DIFFUSE FRONTAL ZONE EXTENDING FROM ARKLATEX NORTHWEST INTO SW
KANSAS THIS EVENING IS EXPECTED TO GRADUALLY LIFT NORTH OVERNIGHT.
00Z NAM SHOWS BOUNDARY AT 8590MB FROM ABOUT FSM-ICT BY 12Z
THURSDAY. CLUSTERS OF STORMS CONTINUE TO ORGANIZE ACROSS NEBRASKA
AND NORTHERN KANSAS THIS EVENING AND SHOULD CONTINUE GROWING
UPSCALE AS LOW LEVEL WARM ADVECTION STRENGTHENS. GOOD CHANCE THAT
AN ORGANIZED COMPLEX OF STORMS WILL DEVELOP THERE AND MOVE SE
OVERNIGHT LIKELY REACHING PARTS OF NE OKLAHOMA BEFORE 12Z.
EXISTING FORECAST POP CONFIGURATION BASICALLY GOOD...BUT HAVE
RAISED TO LIKELY IN AREAS NW OF TULSA AFTER 09Z AS HRRR HAS
REMAINED VERY CONSISTENT IN BRINGING COMPLEX TO THESE AREAS
09-12Z. ALSO BUMPED POPS UP SOME FOR 12-18Z THURSDAY NORTH OF
I-40. SEVERE THREAT WILL BE DEPENDENT ON HOW ORGANIZED COLD POOL
CAN BECOME...AT THIS TIME IT STILL LOOKS LIMITED. UPDATED PRODUCTS
WILL BE OUT SHORTLY.
PREV DISCUSSION... /ISSUED 628 PM CDT WED JUL 9 2014/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
VFR CONDITIONS EXPECTED THIS EVENING AND THROUGH MOST OF
THE NIGHT. THUNDERSTORMS SHOULD DEVELOP ACROSS KS TONIGHT
EVENTUALLY IMPACTING ALL TAF SITES AROUND 10-12Z. BRIEF
MVFR CIGS/VSBYS POSSIBLE IN AND NEAR STORMS.
PREV DISCUSSION... /ISSUED 341 PM CDT WED JUL 9 2014/
DISCUSSION...
WEAKENING FRONTAL ZONE REMAINS ALONG THE RED RIVER AND WILL BEGIN
ITS NORTHEASTWARD MOVEMENT TONIGHT THROUGH THURSDAY. THE MOST
LIKELY SCENARIO FOR OVERNIGHT STORMS IS AN EXPANDING COMPLEX
TO DEVELOP ACROSS THE HIGH PLAINS...AND TRACK SOUTHEASTWARD INTO
THE AREA. HIGHEST PRECIP CHANCES WILL BE FOCUSED ACROSS NORTHERN
AND EASTERN PORTIONS OF THE FORECAST AREA ACCORDINGLY.
THE RETURN TO HOT AND HUMID CONDITIONS WILL BEGIN ON FRIDAY WITH
TEMPERATURES PEAKING SATURDAY INTO SUNDAY. A FEW STORMS MAY
DEVELOP IN THE HIGHER TERRAIN EACH DAY HOWEVER CHANCES WILL REMAIN
VERY LOW.
AN INITIAL WIND SHIFT BEING AN INITIAL FRONTAL BOUNDARY AND/OR
CONVECTIVE OUTFLOW WILL MAKE A PUSH INTO NORTHEAST OKLAHOMA ON
SUNDAY. THIS RAISES UNCERTAINTIES ON TEMPS IN THIS ZONE...WHILE HOT
TEMPS PREVAIL FURTHER SOUTH ACROSS MUCH OF THE FORECAST AREA. THIS
BOUNDARY WILL SLOWLY WORK SOUTHWARD SUNDAY NIGHT THROUGH
MONDAY...BEFORE A STRONGER SURGE OF COOLER AND DRIER AIR ARRIVES
FOR TUESDAY THROUGH MID NEXT WEEK. THE BOUNDARY WILL ALSO MARK A
ZONE OF INCREASED PRECIPITATION CHANCES. THE TEMPERATURES FOR MID
TO LATE NEXT WEEK CONTINUE TO BE SHOWN ABNORMALLY COOL FOR THIS
TIME OF THE YEAR...AND SHOULD THIS VERIFY IT WILL BE A MARKED
CHANGE FROM THE UPCOMING WEEKEND TEMPS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 69 91 75 97 / 40 50 0 0
FSM 70 91 73 94 / 10 40 0 0
MLC 73 92 74 94 / 20 10 0 0
BVO 65 87 72 97 / 50 50 0 0
FYV 63 87 70 89 / 10 40 10 10
BYV 63 86 69 89 / 10 30 10 10
MKO 69 91 73 94 / 20 40 0 0
MIO 65 88 71 92 / 20 50 10 0
F10 71 91 73 94 / 20 30 0 0
HHW 72 94 73 95 / 20 10 0 0
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
SHORT TERM...99
LONG TERM....99
AVIATION...18
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
721 AM EDT THU JUL 10 2014
.SYNOPSIS...
A PERSISTENT UPPER LEVEL TROUGH OVER THE GREAT LAKES WILL DAMPEN
AS IT CROSSES THE NEW ENGLAND STATES INTO THE WEEKEND...WITH A
WEAKENING QUASI-STATIONARY FRONT TRAILING SOUTHWARD ALONG THE MID
ATLANTIC COAST. DESPITE THE INFLUENCE OF HIGH PRESSURE AT THE
SURFACE...THE AREA WILL REMAIN VULNERABLE TO ISOLATED SHOWERS AND
THUNDERSTORMS INTO THE FIRST PART OF THE WEEKEND. A SERIES OF
REINFORCING COLD FRONTS WILL PROVIDE SEVERAL OPPORTUNITIES FOR
RAINFALL THROUGH EARLY NEXT WEEK...WHILE HELPING TO CARVE OUT A
HIGHLY ANOMALOUS UPPER TROUGH AND BONAFIDE POLAR VORTEX ACROSS
SOUTHEASTERN CANADA AND THE UPPER GREAT LAKES.
&&
.NEAR TERM /THROUGH TONIGHT/...
DWINDLING SHRA CONTINUE TO RIDE ALONG DYING SECONDARY COLD FRONT
ACROSS THE N MTNS EARLY THIS MORNING. LATEST RAP SUGGESTS THESE
SHOWERS DISAPPEAR TOWARD DAWN...AS BLYR CONTINUES TO COOL/STABILIZE.
ELSEWHERE...MCLEAR SKIES AND A LIGHT WIND HAVE RESULTED IN PATCHY
FOG. 11-3.9U IMAGERY INDICATES THE MOST EXTENSIVE FOG/LOW CLOUDS
ARE ACROSS THE NW MTNS.
ANY FOG AND LOW CLOUDS WILL BURN OFF SHORTLY AFTER DAWN...GIVING
WAY TO M/SUNNY START TO THE DAY OVER MOST OF CENTRAL PA.
HOWEVER...AN UPPER LEVEL TROUGH MOVG EWD ACRS THE LOWER GRT
LKS...COMBINED WITH WEAK INSTABILITY...SHOULD BE ENOUGH TO
GENERATE SCT SHRA/TSRA DURING THE AFTN...MAINLY ACRS THE SCNTRL
MTNS. 8H TEMPS BTWN 12-14C SHOULD TRANSLATE TO HIGHS FROM THE M70S
OVR THE HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE M80S ACROSS
THE LOWER SUSQ VALLEY.
A SHOWER OR TWO MAY LINGER OVER THE SERN ZONES LATE THIS
EVE...BUT HIGH PRES WILL DOMINATE FOR THE MOST PART WITH CLEARING
AND PATCHY VALLEY FOG DEVELOPING OVERNIGHT AND INTO EARLY FRIDAY
MORNING. GFS MOS APPEARS TOO COOL TONIGHT BASED ON BLEND OF ALL
MDL SFC DWPTS. BCCONSALL APPEARS MUCH MORE REASONABLE...WITH LOWS
RANGING FROM THE L50S OVR THE NW MTNS TO THE M60S OVR THE LOWER
SUSQ VALLEY.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
VERY LITTLE CHANGE IN THE OVERALL PATTERN EXPECTED INTO DAY 2
WITH EVEN WEAKER FORCING ALOFT DUE TO DAMPENING OF UPPER TROUGH.
EXPECT BULK OF PCPN TO REMAIN CONFINED TO ERN NC/VA TO THE
DELMARVA NEAR Q-STNRY FRONT AND HI MSTR PWS AXIS. STILL CANT RULE
OUT AN ISOLD SHRA/TSTM DURING THE AFTN OVER ERN PRTNS OF THE CWA
BUT POPS WILL BE BARELY MENTIONABLE/AOB 20 PCT. TEMPS SHOULD EDGE
A LITTLE WARMER THAN THURSDAY. STG WAA UPSTREAM OVER THE GRT
LKS/OH VLY WILL LKLY BRING SOME MID-HIGH CLOUDS INTO WRN SXNS BY
12Z SAT.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
THE AREA SHOULD BE IN MORE OF A RETURN FLOW REGIME BY SAT AS THE
SFC HIGH SLIPS OFF THE EAST COAST. SIMILAR TO DAYS 1 AND 2..STILL
CANT RULE OUT AN ISOLD SHRA/TSTM IN SPOTS WHILE MOST AREAS STAY
DRY. STALLED FRONT ALONG THE SOUTHEAST COAST SHOULD PIVOT BACK
NWD AS WARM FRONT SAT NGT INTO EARLY SUNDAY WITH S-SWLY LLJ INC
LLVL MSTR FLUX THRU THE UPPER OH VLY INTO WRN PA IN ADVANCE OF
LEAD SHORTWAVE ENERGY AND ASSOCD SFC COLD FRONT MOVG SEWD ACRS THE
GRT LKS-MIDWEST.
AMPLIFICATION OF THE UPPER PATTERN BEGINS EARLY NEXT WEEK WITH A
MODEL CONSENSUS GENERALLY INDICATING A FRONTAL PCPN AXIS SHIFTING
SEWD THRU THE GRT LKS/OH VLY REGIONS INTO CENTRAL PA SUN-MON.
ALTHOUGH PREDICTABILITY IS TOO LOW ATTM...A SEVERE WX THREAT
SHOULD SPREAD SEWD IN TIME FROM THE UPPER MIDWEST/GRT LKS/OH VLY
INTO THE MID ATLC AND NORTHEAST STATES...ALONG SRN PERIPHERY OF
STRONGER WINDS/CYC FLOW ALOFT AND SEVERAL REINFORCING COLD
FRONTAL SURGES ASSOCIATED WITH THE AMPLIFYING SYNOPTIC UPPER
TROUGH. EACH COLD FRONTAL SURGE WILL PROVIDE AN OPPORTUNITY FOR
SHOWERS/TSTMS THROUGH AT LEAST TUESDAY.
THE HIGHLY ANOMALOUS AMPLIFICATION OF THE LARGE SCALE PATTERN IS
A VIRTUAL LOCK BY THE END OF THE PERIOD AS INDICATED BY ALL MEDIUM
RANGE GLOBAL NUMERICAL MODELS AND ENSEMBLE SYSTEMS. THIS WELL-
ADVERTISED HIGH MERIDIONAL EVENT WILL FEATURE A FULL-LATITUDE
RIDGE AND SEARING HEAT OUT WEST...NOT BE BE OUTDONE BY THE RETURN
OF THE POLAR VORTEX IN THE EAST OVER QUE/ONT AND THE UPPER GREAT
LAKES. CONSIDERING THE MAGNITUDE OF THE UPPER LEVEL TROUGH WITH
500MB STANDARDIZED ANOMALIES ON THE ORDER OF -3 TO -4SD IN BOTH
THE DETERMINISTIC GLOBAL MODELS AND THEIR RESPECTIVE ENSEMBLE
MEANS...CONFIDENCE IN A PERIOD OF BELOW AVG TEMPS /DURING WHAT IS
CLIMATOLOGICALLY THE HOTTEST TIME OF THE YEAR/ IS VERY HIGH FROM
TUE-THU OF NEXT WEEK.
&&
.AVIATION /11Z THURSDAY THROUGH MONDAY/...
11-3.9UM SATL IMAGERY SHOWING EXTENSIVE VALLEY FOG ACROSS THE
NORTHERN MTNS EARLY THIS MORNING. HOWEVER...ANY LOW CIGS/FOG
SHOULD RAPIDLY MIX OUT ARND 12Z...WITH PREDOMINATELY VFR CONDS
EXPECTED FOR THE REST OF THE DAY. HOWEVER...A TROUGH OF LOW PRES
APPROACHING FROM THE WEST WILL LIKELY TRIGGER SCT SHRA/TSRA DURING
THE AFTN AND EVENING HRS. THE BEST CHANCE OF A BRIEF VIS REDUCTION
WILL BE ACROSS THE SC MTNS...INCLUDING KJST AND KAOO.
CLEARING SKIES AND A LIGHT WIND WILL PROMOTE PATCHY FOG
TONIGHT...ESP WHERE RAIN FALLS LATER TODAY.
OUTLOOK...
FRI-SAT...PATCHY AM FOG POSSIBLE.
SUN-MON...BRIEF...MAINLY PM...THUNDERSTORM IMPACTS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...FITZGERALD
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
525 AM EDT THU JUL 10 2014
.SYNOPSIS...
A PERSISTENT UPPER LEVEL TROUGH OVER THE GREAT LAKES WILL DAMPEN
AS IT CROSSES THE NEW ENGLAND STATES INTO THE WEEKEND...WITH A
WEAKENING QUASI-STATIONARY FRONT TRAILING SOUTHWARD ALONG THE MID
ATLANTIC COAST. DESPITE THE INFLUENCE OF HIGH PRESSURE AT THE
SURFACE...THE AREA WILL REMAIN VULNERABLE TO ISOLATED SHOWERS AND
THUNDERSTORMS INTO THE FIRST PART OF THE WEEKEND. A SERIES OF
REINFORCING COLD FRONTS WILL PROVIDE SEVERAL OPPORTUNITIES FOR
RAINFALL THROUGH EARLY NEXT WEEK...WHILE HELPING TO CARVE OUT A
HIGHLY ANOMALOUS UPPER TROUGH AND BONAFIDE POLAR VORTEX ACROSS
SOUTHEASTERN CANADA AND THE UPPER GREAT LAKES.
&&
.NEAR TERM /THROUGH TONIGHT/...
DWINDLING SHRA CONTINUE TO RIDE ALONG DYING SECONDARY COLD FRONT
ACROSS THE N MTNS EARLY THIS MORNING. LATEST RAP SUGGESTS THESE
SHOWERS DISAPPEAR TOWARD DAWN...AS BLYR CONTINUES TO COOL/STABILIZE.
ELSEWHERE...MCLEAR SKIES AND A LIGHT WIND HAVE RESULTED IN PATCHY
FOG. 11-3.9U IMAGERY INDICATES THE MOST EXTENSIVE FOG/LOW CLOUDS
ARE ACROSS THE NW MTNS.
ANY FOG AND LOW CLOUDS WILL BURN OFF SHORTLY AFTER DAWN...GIVING
WAY TO M/SUNNY START TO THE DAY OVER MOST OF CENTRAL PA.
HOWEVER...AN UPPER LEVEL TROUGH MOVG EWD ACRS THE LOWER GRT
LKS...COMBINED WITH WEAK INSTABILITY...SHOULD BE ENOUGH TO
GENERATE SCT SHRA/TSRA DURING THE AFTN...MAINLY ACRS THE SCNTRL
MTNS. 8H TEMPS BTWN 12-14C SHOULD TRANSLATE TO HIGHS FROM THE M70S
OVR THE HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE M80S ACROSS
THE LOWER SUSQ VALLEY.
A SHOWER OR TWO MAY LINGER OVER THE SERN ZONES LATE THIS
EVE...BUT HIGH PRES WILL DOMINATE FOR THE MOST PART WITH CLEARING
AND PATCHY VALLEY FOG DEVELOPING OVERNIGHT AND INTO EARLY FRIDAY
MORNING. GFS MOS APPEARS TOO COOL TONIGHT BASED ON BLEND OF ALL
MDL SFC DWPTS. BCCONSALL APPEARS MUCH MORE REASONABLE...WITH LOWS
RANGING FROM THE L50S OVR THE NW MTNS TO THE M60S OVR THE LOWER
SUSQ VALLEY.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
VERY LITTLE CHANGE IN THE OVERALL PATTERN EXPECTED INTO DAY 2
WITH EVEN WEAKER FORCING ALOFT DUE TO DAMPENING OF UPPER TROUGH.
EXPECT BULK OF PCPN TO REMAIN CONFINED TO ERN NC/VA TO THE
DELMARVA NEAR Q-STNRY FRONT AND HI MSTR PWS AXIS. STILL CANT RULE
OUT AN ISOLD SHRA/TSTM DURING THE AFTN OVER ERN PRTNS OF THE CWA
BUT POPS WILL BE BARELY MENTIONABLE/AOB 20 PCT. TEMPS SHOULD EDGE
A LITTLE WARMER THAN THURSDAY. STG WAA UPSTREAM OVER THE GRT
LKS/OH VLY WILL LKLY BRING SOME MID-HIGH CLOUDS INTO WRN SXNS BY
12Z SAT.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
THE AREA SHOULD BE IN MORE OF A RETURN FLOW REGIME BY SAT AS THE
SFC HIGH SLIPS OFF THE EAST COAST. SIMILAR TO DAYS 1 AND 2..STILL
CANT RULE OUT AN ISOLD SHRA/TSTM IN SPOTS WHILE MOST AREAS STAY
DRY. STALLED FRONT ALONG THE SOUTHEAST COAST SHOULD PIVOT BACK
NWD AS WARM FRONT SAT NGT INTO EARLY SUNDAY WITH S-SWLY LLJ INC
LLVL MSTR FLUX THRU THE UPPER OH VLY INTO WRN PA IN ADVANCE OF
LEAD SHORTWAVE ENERGY AND ASSOCD SFC COLD FRONT MOVG SEWD ACRS THE
GRT LKS-MIDWEST.
AMPLIFICATION OF THE UPPER PATTERN BEGINS EARLY NEXT WEEK WITH A
MODEL CONSENSUS GENERALLY INDICATING A FRONTAL PCPN AXIS SHIFTING
SEWD THRU THE GRT LKS/OH VLY REGIONS INTO CENTRAL PA SUN-MON.
ALTHOUGH PREDICTABILITY IS TOO LOW ATTM...A SEVERE WX THREAT
SHOULD SPREAD SEWD IN TIME FROM THE UPPER MIDWEST/GRT LKS/OH VLY
INTO THE MID ATLC AND NORTHEAST STATES...ALONG SRN PERIPHERY OF
STRONGER WINDS/CYC FLOW ALOFT AND SEVERAL REINFORCING COLD
FRONTAL SURGES ASSOCIATED WITH THE AMPLIFYING SYNOPTIC UPPER
TROUGH. EACH COLD FRONTAL SURGE WILL PROVIDE AN OPPORTUNITY FOR
SHOWERS/TSTMS THROUGH AT LEAST TUESDAY.
THE HIGHLY ANOMALOUS AMPLIFICATION OF THE LARGE SCALE PATTERN IS
A VIRTUAL LOCK BY THE END OF THE PERIOD AS INDICATED BY ALL MEDIUM
RANGE GLOBAL NUMERICAL MODELS AND ENSEMBLE SYSTEMS. THIS WELL-
ADVERTISED HIGH MERIDIONAL EVENT WILL FEATURE A FULL-LATITUDE
RIDGE AND SEARING HEAT OUT WEST...NOT BE BE OUTDONE BY THE RETURN
OF THE POLAR VORTEX IN THE EAST OVER QUE/ONT AND THE UPPER GREAT
LAKES. CONSIDERING THE MAGNITUDE OF THE UPPER LEVEL TROUGH WITH
500MB STANDARDIZED ANOMALIES ON THE ORDER OF -3 TO -4SD IN BOTH
THE DETERMINISTIC GLOBAL MODELS AND THEIR RESPECTIVE ENSEMBLE
MEANS...CONFIDENCE IN A PERIOD OF BELOW AVG TEMPS /DURING WHAT IS
CLIMATOLOGICALLY THE HOTTEST TIME OF THE YEAR/ IS VERY HIGH FROM
TUE-THU OF NEXT WEEK.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
11-3.9UM SATL IMAGERY SHOWING EXTENSIVE VALLEY FOG ACROSS THE
NORTHERN MTNS EARLY THIS MORNING. A COMBINATION OF 09Z SFC
OBS...CONDITIONAL CLIMATOLOGY AND LATEST RAP OUTPUT SUGGEST
KBFD...KIPT AND KUNV WILL EXPERIENCE SOME IFR CONDS IN THE 09Z-11Z
TIME FRAME.
ANY LOW CIGS/FOG SHOULD RAPIDLY MIX OUT BY 12Z...WITH
PREDOMINATELY VFR CONDS EXPECTED FOR THE REST OF THE DAY.
HOWEVER...A TROUGH OF LOW PRES APPROACHING FROM THE WEST WILL
LIKELY TRIGGER SCT SHRA/TSRA DURING THE AFTN AND EVENING HRS. THE
BEST CHANCE OF A BRIEF VIS REDUCTION WILL BE ACROSS THE SC
MTNS...INCLUDING KJST AND KAOO.
OUTLOOK...
FRI-SAT...PATCHY AM FOG POSSIBLE.
SUN-MON...BRIEF...MAINLY PM...THUNDERSTORM IMPACTS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...FITZGERALD
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
502 AM EDT THU JUL 10 2014
.SYNOPSIS...
PERSISTENT UPPER LEVEL TROUGH OVER THE GREAT LAKES WILL DAMPEN AS
IT CROSSES THE NEW ENGLAND STATES INTO THE WEEKEND...WITH A
WEAKENING QUASI-STATIONARY FRONT TRAILING SOUTHWARD ALONG THE MID
ATLANTIC COAST. DESPITE THE INFLUENCE OF HIGH PRESSURE AT THE
SURFACE...THE AREA WILL REMAIN VULNERABLE TO MAINLY ISOLATED
SHOWERS AND THUNDERSTORMS INTO THE FIRST PART OF THE WEEKEND. A
SERIES OF REINFORCING FRONTS PROVIDE SEVERAL OPPORTUNITIES FOR
RAIN THE MIDDLE OF NEXT WEEK...WHILE HELPING TO CARVE OUT A
BONAFIDE POLAR VORTEX OVER SOUTHEASTERN CANADA AND THE UPPER GREAT
LAKES.
&&
.NEAR TERM /THROUGH TONIGHT/...
DWINDLING SHRA CONTINUE TO RIDE ALONG DYING SECONDARY COLD FRONT
ACROSS THE N MTNS EARLY THIS MORNING. LATEST RAP SUGGESTS THESE
SHOWERS DISAPPEAR TOWARD DAWN...AS BLYR CONTINUES TO COOL/STABILIZE.
ELSEWHERE...MCLEAR SKIES AND A LIGHT WIND HAVE RESULTED IN PATCHY
FOG. 11-3.9U IMAGERY INDICATES THE MOST EXTENSIVE FOG/LOW CLOUDS
ARE ACROSS THE NW MTNS.
ANY FOG AND LOW CLOUDS WILL BURN OFF SHORTLY AFTER DAWN...GIVING
WAY TO M/SUNNY START TO THE DAY OVER MOST OF CENTRAL PA.
HOWEVER...AN UPPER LEVEL TROUGH MOVG EWD ACRS THE LOWER GRT
LKS...COMBINED WITH WEAK INSTABILITY...SHOULD BE ENOUGH TO
GENERATE SCT SHRA/TSRA DURING THE AFTN...MAINLY ACRS THE SCNTRL
MTNS. 8H TEMPS BTWN 12-14C SHOULD TRANSLATE TO HIGHS FROM THE M70S
OVR THE HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE M80S ACROSS
THE LOWER SUSQ VALLEY.
A SHOWER OR TWO MAY LINGER OVER THE SERN ZONES LATE THIS
EVE...BUT HIGH PRES WILL DOMINATE FOR THE MOST PART WITH CLEARING
AND PATCHY VALLEY FOG DEVELOPING OVERNIGHT AND INTO EARLY FRIDAY
MORNING. GFS MOS APPEARS TOO COOL TONIGHT BASED ON BLEND OF ALL
MDL SFC DWPTS. BCCONSALL APPEARS MUCH MORE REASONABLE...WITH LOWS
RANGING FROM THE L50S OVR THE NW MTNS TO THE M60S OVR THE LOWER
SUSQ VALLEY.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
VERY LITTLE CHANGE IN THE OVERALL PATTERN EXPECTED INTO DAY 2
WITH EVEN WEAKER FORCING ALOFT DUE TO DAMPENING OF UPPER TROUGH.
EXPECT BULK OF PCPN TO REMAIN CONFINED TO ERN NC/VA TO THE
DELMARVA NEAR Q-STNRY FRONT AND HI MSTR AXIS. STILL CANT RULE OUT
AN ISOLD SHRA/TSTM DURING THE AFTN OVER ERN PRTNS OF THE CWA BUT
POPS WILL BE BARELY MENTIONABLE/AOB 20 PCT. TEMPS SHOULD EDGE A
LITTLE WARMER THAN THURSDAY. STG WAA UPSTREAM OVER THE GRT LKS/OH
VLY SHOULD BRING SOME CLOUDS INTO WRN SXNS BY 12Z SAT.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
THE AREA SHOULD BE IN MORE OF A RETURN FLOW REGIME BY SAT AS THE
SFC HIGH SLIPS OFF THE EAST COAST. SIMILAR TO DAYS 1 AND 2..STILL
CANT RULE OUT AN ISOLD SHRA/TSTM IN SPOTS WHILE MOST AREAS STAY
DRY. STALLED FRONT ALONG THE EAST COAST SHOULD PIVOT BACK NWD AS
WARM FRONT SAT NGT INTO EARLY SUNDAY WITH S-SWLY LLJ INC LLVL MSTR
FLUX THRU THE UPPER OH VLY INTO WRN PA IN ADVANCE OF LEAD SHORTWAVE
ENERGY AND ASSOCD SFC COLD FRONT MOVG SEWD ACRS THE GRT LKS-MIDWEST.
AMPLIFICATION OF THE UPPER PATTERN BEGINS EARLY NEXT WEEK WITH A
MODEL CONSENSUS GENERALLY INDICATING A FRONTAL PCPN AXIS SHIFTING
SEWD THRU THE GRT LKS/OH VLY REGIONS INTO CENTRAL PA SUN-MON. ALTHOUGH
PREDICTABILITY IS TOO LOW ATTM...A SEVERE WX THREAT SHOULD SPREAD
SEWD IN TIME FROM THE UPPER MIDWEST/GRT LKS/OH VLY INTO THE MID
ATLC AND NORTHEAST STATES...ALONG SRN PERIPHERY OF STRONGER WINDS
ALOFT AND SEVERAL REINFORCING COLD FRONTAL SURGES ASSOCIATED WITH
THE AMPLIFYING SYNOPTIC UPPER TROUGH. EACH COLD FRONTAL SURGE WILL
PROVIDE AN OPPORTUNITY FOR SHOWERS/TSTMS THROUGH AT LEAST TUESDAY.
A HIGHLY ANOMALOUS AMPLIFICATION OF THE UPPER PATTERN IS A VIRTUAL
LOCK BY THE END OF THE PERIOD AS INDICATED BY ALL MEDIUM RANGE
GLOBAL NUMERICAL MODELS AND ENSEMBLE SYSTEMS...FEATURING A FULL-
LATITUDE RIDGE AND SEARING HEAT OUT WEST NOT BE BE OUTDONE BY THE
RETURN OF THE POLAR VORTEX IN THE EAST OVER QUE/ONT AND THE UPPER
GREAT LAKES. CONSIDERING THE MAGNITUDE OF THE UPPER LEVEL TROUGH
WITH STANDARDIZED ANOMALIES ON THE ORDER OF -3 TO -4SD IN BOTH THE
DETERMINISTIC GLOBAL MODELS AND THEIR RESPECTIVE ENSEMBLE
MEANS...CONFIDENCE IN A PERIOD OF BELOW AVG TEMPS /DURING WHAT IS
CLIMATOLOGICALLY THE HOTTEST TIME OF THE YEAR/ IS QUITE HIGH FROM
TUE-THU OF NEXT WEEK.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
11-3.9UM SATL IMAGERY SHOWING EXTENSIVE VALLEY FOG ACROSS THE
NORTHERN MTNS EARLY THIS MORNING. A COMBINATION OF 09Z SFC
OBS...CONDITIONAL CLIMATOLOGY AND LATEST RAP OUTPUT SUGGEST
KBFD...KIPT AND KUNV WILL EXPERIENCE SOME IFR CONDS IN THE 09Z-11Z
TIME FRAME.
ANY LOW CIGS/FOG SHOULD RAPIDLY MIX OUT BY 12Z...WITH
PREDOMINATELY VFR CONDS EXPECTED FOR THE REST OF THE DAY.
HOWEVER...A TROUGH OF LOW PRES APPROACHING FROM THE WEST WILL
LIKELY TRIGGER SCT SHRA/TSRA DURING THE AFTN AND EVENING HRS. THE
BEST CHANCE OF A BRIEF VIS REDUCTION WILL BE ACROSS THE SC
MTNS...INCLUDING KJST AND KAOO.
OUTLOOK...
FRI-SAT...PATCHY AM FOG POSSIBLE.
SUN-MON...BRIEF...MAINLY PM...THUNDERSTORM IMPACTS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...FITZGERALD
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
430 AM EDT THU JUL 10 2014
.SYNOPSIS...
PERSISTENT UPPER LEVEL TROUGH OVER THE GREAT LAKES WILL DAMPEN AS
IT CROSSES THE NEW ENGLAND STATES INTO THE WEEKEND...WITH A
WEAKENING QUASI-STATIONARY FRONT TRAILING SOUTHWARD ALONG THE MID
ATLANTIC COAST. DESPITE THE INFLUENCE OF HIGH PRESSURE AT THE
SURFACE...THE AREA WILL REMAIN VULNERABLE TO MAINLY ISOLATED
SHOWERS AND THUNDERSTORMS INTO THE FIRST PART OF THE WEEKEND. A
SERIES OF REINFORCING FRONTS PROVIDE SEVERAL OPPORTUNITIES FOR
RAIN THE MIDDLE OF NEXT WEEK...WHILE HELPING TO CARVE OUT A
BONAFIDE POLAR VORTEX OVER SOUTHEASTERN CANADA AND THE UPPER GREAT
LAKES.
&&
.NEAR TERM /THROUGH TONIGHT/...
DWINDLING SHRA CONTINUE TO RIDE ALONG DYING SECONDARY COLD FRONT
ACROSS THE N MTNS EARLY THIS MORNING. LATEST RAP SUGGESTS THESE
SHOWERS DISAPPEAR TOWARD DAWN...AS BLYR CONTINUES TO COOL/STABILIZE.
ELSEWHERE...MCLEAR SKIES AND A LIGHT WIND HAVE RESULTED IN PATCHY
FOG. 11-3.9U IMAGERY INDICATES THE MOST EXTENSIVE FOG/LOW CLOUDS
ARE ACROSS THE NW MTNS.
ANY FOG AND LOW CLOUDS WILL BURN OFF SHORTLY AFTER DAWN...GIVING
WAY TO M/SUNNY START TO THE DAY OVER MOST OF CENTRAL PA.
HOWEVER...AN UPPER LEVEL TROUGH MOVG EWD ACRS THE LOWER GRT
LKS...COMBINED WITH WEAK INSTABILITY...SHOULD BE ENOUGH TO
GENERATE SCT SHRA/TSRA DURING THE AFTN...MAINLY ACRS THE SCNTRL
MTNS. 8H TEMPS BTWN 12-14C SHOULD TRANSLATE TO HIGHS FROM THE M70S
OVR THE HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE M80S ACROSS
THE LOWER SUSQ VALLEY.
A SHOWER OR TWO MAY LINGER OVER THE SERN ZONES LATE THIS
EVE...BUT HIGH PRES WILL DOMINATE FOR THE MOST PART WITH CLEARING
AND PATCHY VALLEY FOG DEVELOPING OVERNIGHT AND INTO EARLY FRIDAY
MORNING. GFS MOS APPEARS TOO COOL TONIGHT BASED ON BLEND OF ALL
MDL SFC DWPTS. BCCONSALL APPEARS MUCH MORE REASONABLE...WITH LOWS
RANGING FROM THE L50S OVR THE NW MTNS TO THE M60S OVR THE LOWER
SUSQ VALLEY.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
VERY LITTLE CHANGE IN THE OVERALL PATTERN EXPECTED INTO DAY 2
WITH EVEN WEAKER FORCING ALOFT DUE TO DAMPENING OF UPPER TROUGH.
EXPECT BULK OF PCPN TO REMAIN CONFINED TO ERN NC/VA TO THE
DELMARVA NEAR Q-STNRY FRONT AND HI MSTR AXIS. STILL CANT RULE OUT
AN ISOLD SHRA/TSTM DURING THE AFTN OVER ERN PRTNS OF THE CWA BUT
POPS WILL BE BARELY MENTIONABLE/AOB 20 PCT. TEMPS SHOULD EDGE A
LITTLE WARMER THAN THURSDAY. STG WAA UPSTREAM OVER THE GRT LKS/OH
VLY SHOULD BRING SOME CLOUDS INTO WRN SXNS BY 12Z SAT.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
THE AREA SHOULD BE IN MORE OF A RETURN FLOW REGIME BY SAT AS THE
SFC HIGH SLIPS OFF THE EAST COAST. SIMILAR TO DAYS 1 AND 2..STILL
CANT RULE OUT AN ISOLD SHRA/TSTM IN SPOTS WHILE MOST AREAS STAY
DRY. STALLED FRONT ALONG THE EAST COAST SHOULD PIVOT BACK NWD AS
WARM FRONT SAT NGT INTO EARLY SUNDAY WITH S-SWLY LLJ INC LLVL MSTR
FLUX THRU THE UPPER OH VLY INTO WRN PA IN ADVANCE OF LEAD SHORTWAVE
ENERGY AND ASSOCD SFC COLD FRONT MOVG SEWD ACRS THE GRT LKS-MIDWEST.
AMPLIFICATION OF THE UPPER PATTERN BEGINS EARLY NEXT WEEK WITH A
MODEL CONSENSUS GENERALLY INDICATING A FRONTAL PCPN AXIS SHIFTING
SEWD THRU THE GRT LKS/OH VLY REGIONS INTO CENTRAL PA SUN-MON. ALTHOUGH
PREDICTABILITY IS TOO LOW ATTM...A SEVERE WX THREAT SHOULD SPREAD
SEWD IN TIME FROM THE UPPER MIDWEST/GRT LKS/OH VLY INTO THE MID
ATLC AND NORTHEAST STATES...ALONG SRN PERIPHERY OF STRONGER WINDS
ALOFT AND SEVERAL REINFORCING COLD FRONTAL SURGES ASSOCIATED WITH
THE AMPLIFYING SYNOPTIC UPPER TROUGH. EACH COLD FRONTAL SURGE WILL
PROVIDE AN OPPORTUNITY FOR SHOWERS/TSTMS THROUGH AT LEAST TUESDAY.
A HIGHLY ANOMALOUS AMPLIFICATION OF THE UPPER PATTERN IS A VIRTUAL
LOCK BY THE END OF THE PERIOD AS INDICATED BY ALL MEDIUM RANGE
GLOBAL NUMERICAL MODELS AND ENSEMBLE SYSTEMS...FEATURING A FULL-
LATITUDE RIDGE AND SEARING HEAT OUT WEST NOT BE BE OUTDONE BY THE
RETURN OF THE POLAR VORTEX IN THE EAST OVER QUE/ONT AND THE UPPER
GREAT LAKES. CONSIDERING THE MAGNITUDE OF THE UPPER LEVEL TROUGH
WITH STANDARDIZED ANOMALIES ON THE ORDER OF -3 TO -4SD IN BOTH THE
DETERMINISTIC GLOBAL MODELS AND THEIR RESPECTIVE ENSEMBLE
MEANS...CONFIDENCE IN A PERIOD OF BELOW AVG TEMPS /DURING WHAT IS
CLIMATOLOGICALLY THE HOTTEST TIME OF THE YEAR/ IS QUITE HIGH FROM
TUE-THU OF NEXT WEEK.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
CENTRAL PA REMAINS IN A REGION OF RELATIVELY HIGH LOW-LVL
MOISTURE TODAY...EVEN THOUGH STALLED COLD FRONT IS NOW EAST OF THE
AREA. THE MAIN AVIATION CONCERN THIS MORNING WILL BE THE POSSIBILITY
OF PATCHY FOG/LOW CIGS DUE TO RADIATIONAL COOLING. A COMBINATION
OF 05Z DWPT DEPRESSIONS...CONDITIONAL CLIMATOLOGY AND LATEST RAP
OUTPUT SUGGEST KBFD AND KIPT ARE MOST SUSCEPTIBLE TO A PERIOD OF
IFR CONDS EARLY THIS MORNING. KIPT ALREADY HAS A 500FT CIG AT
05Z...BUT ARRIVAL OF MID LVL CLOUDS MAY BRIEFLY IMPROVE CONDS BTWN
06Z-08Z.
ANY LOW CIGS/FOG SHOULD RAPIDLY MIX OUT BY 12Z...WITH
PREDOMINATELY VFR CONDS EXPECTED FOR THE REST OF THE DAY.
HOWEVER...A TROUGH OF LOW PRES APPROACHING FROM THE WEST WILL
LIKELY TRIGGER SCT SHRA/TSRA DURING THE AFTN AND EVENING HRS. THE
BEST CHANCE OF A BRIEF VIS REDUCTION WILL BE ACROSS THE SC
MTNS...INCLUDING KJST AND KAOO.
OUTLOOK...
FRI-SAT...PATCHY AM FOG POSSIBLE.
SUN-MON...BRIEF...MAINLY PM...THUNDERSTORM IMPACTS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...FITZGERALD/STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
204 AM EDT THU JUL 10 2014
.SYNOPSIS...
A FRONTAL BOUNDARY WILL PUSH THROUGH THE AREA TONIGHT AND REMAINS IN
PLACE THURSDAY BEFORE WASHING OUT BY FRIDAY. WEAK HIGH PRESSURE WILL
RETURN THROUGH THE WEEKEND BEFORE ANOTHER COLD FRONT APPROACHES THE
AREA EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 2 AM...REMNANT SHOWER AREA ASSOCIATED WITH EARLIER CONVECTIVE
COMPLEX IS BEGINNING TO LIFT AWAY FROM THE I-40 CORRIDOR...WHILE
ADDITIONAL SHOWER ACTIVITY WAS APPROACHING THE UPPER SAVANNAH RIVER
VALLEY. EVEN THIS WAS BEGINNING TO SHOW SIGNS OF STRUGGLING AGAINST
THE INCREASINGLY STABLE AIR MASS OVER THE AREA. POPS HAVE BEEN
INCREASED FOR THE NEXT FEW HOURS TO ACCOUNT FOR THESE TWO AREAS OF
CONVECTION...BUT FEEL THAT WE SHOULD BE FREE OF ALL BUT A COUPLE OF
STRAY SHOWERS BY DAYBREAK.
AS OF 915 PM...A BAND OF SHOWERS AND THUNDERSTORMS WAS DRIFTING EAST
ACROSS THE NC MTNS. LATEST MESOSCALE ANALYSIS INDICATED THAT CAPE
VALUES ALONG AND AHEAD OF THE CONVECTION RANGED FROM 500-1000 J/KG
WITH LITTLE TO NO CIN. HOWEVER...CIN IS ANTICIPATED TO INCREASE
ACROSS THE REGION OVER THE NEXT TWO HOURS. I WILL UPDATE THE
FORECAST TO ACCOUNT FOR THE RECENT COVERAGE AND TIME THE PLACEMENT
AND DECREASING COVERAGE FOR THE REST OF THIS EVENING.
AS OF 745 PM...WIDELY SCATTERED SHRA/TSRA REMAINED ACROSS THE
FORECAST AREA. I WILL UPDATE THE FORECAST TO LOWER POPS ACROSS THE
I-77 CORRIDOR...KEEP CHC POPS ELSEWHERE. I WILL ALSO INCREASE THE
MENTION OF FOG ACROSS THE REGION LATE TONIGHT.
AS OF 530 PM...A LARGE CLUSTER OF THUNDERSTORMS WAS PUSHING ACROSS
THE I-77 CORRIDOR. I WILL UPDATE THE FORECAST TO INCREASE POPS OVER
THE NEXT TWO HOURS ACROSS THE CLT METRO AREA. OUTFLOW GOVERNED
TEMPERATURES WILL REMAIN CHALLENGING THROUGH THE EVENING...I WILL
UPDATE WITH OBS.
AT 215PM...MOST THUNDERSTORM COVERAGE AT MID AFTERNOON IS ACROSS THE
SOUTHERN UPSTATE EASTWARD INTO NC. NUMEROUS STORMS DEVELOPED IN A
DIFFERENTIAL HEATING AXIS CREATED BY CLOUD COVER TO NORTH EARLIER
TODAY. PLUS THE LEE TROF HAS PROVIDED SOME LOW LEVEL CONVERGENCE. AN
UPPER SHORT WAVE DEPICTED BY THE RAP IS ALSO CROSSING THE AREA.
SHOULD SEE SOME ADDITIONAL DEVELOPMENT ACROSS THE NC
MOUNTAINS/FOOTHILLS PER CAMS SO WILL CONTINUE WITH SCT TYPE POPS
THOSE AREAS. SHOULD SEE THE COVERAGE OF CONVECTION WANE THIS EVENING
AS S/W MOVES TO THE E. HOWEVER...A COLD FRONT JUST WEST OF THE
APPALACHIANS IS FORECAST TO MOVE INTO THE NC MOUNTAINS THIS EVENING
WHICH COULD KICK OFF SOME ADDITIONAL SHOWERS/THUNDERSTORMS...SO WILL
SHOW AN UPTICK IN POPS OVER THE WEST THIS EVENING AGAIN. THE 12Z GFS
SEEMS TO HAVE SOME CONVECTIVE FEEDBACK OVER FAR WESTERN NC IN THE
00Z-06Z TIME FRAME AND WILL NOT BUY INTO THE HIGH GFS QPF DEPICTED
THERE.
ON THU...THE FRONT IS FORECAST TO REACH THE PIEDMONT. THE MODELS
DEPICT A WEAK WAVE DEVELOPING ON THE BOUNDARY WHICH SHOULD TEND TO
ENHANCE THE COVERAGE NEAR IT. PLUS...ANOTHER WEAK SHORT WAVE IS
FORECAST TO CROSS THE AREA. HENCE...WILL STAY WITH THE IDEA OF
SCT-NUMEROUS SHOWERS/STORMS ACROSS THE PIEDMONT DURING THE
AFTERNOON...WITH LOWER POPS TO THE NORTH. SOUNDINGS LOOK MORE
SATURATED WITH LESS DCAPE...SO DO NOT EXPECT MUCH IN THE WAY OF A
SEVERE THREAT. MAX TEMPS ARE FORECAST TO BE ABOUT A CATEGORY BELOW
CLIMO.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY/...
AS OF 100 PM WEDNESDAY...THE SHORT TERM PERIOD INITIALIZES THURSDAY
EVENING WITH A QUASI STATIONARY FRONTAL BOUNDARY POSITIONED JUST
SOUTH OF INTERSTATE 85 INTO THE MIDLANDS OF SC...STRETCHING
NORTHEASTWARD INTO CENTRAL NC. SCATTERED CONVECTION WILL LIKELY BE
ONGOING AS HEATING WILL HAVE STEEPENED LAPSE RATES IN PROXIMITY TO
THE SURFACE BOUNDARY...WHICH WILL PROVIDE A FOCUS FOR SAID
CONVECTION. MEANWHILE...POSITIVELY TILTED UPPER TROF WILL BE
LIFTING TO THE NORTHEAST ALLOWING H5 HEIGHTS TO RISE. POPS WILL
TAPER DOWN DUE TO RISING HEIGHTS ALOFT AND HEATING LOSS INTO THE
OVERNIGHT HOURS OF FRIDAY MORNING. LATEST GUIDANCE INDICATES
POTENTIAL WEAK MESOLOW DEVELOPMENT ALONG THE FL PANHANDLE ON FRIDAY
MORNING ALLOWING FOR ENHANCED SOUTHEASTERLY FLOW INTO THE
CAROLINAS. THIS COMBINED WITH FLOW AROUND THE WESTERN ATLANTIC
SURFACE RIDGE WILL ALLOW THE STALLED FRONTAL BOUNDARY TO GRADUALLY
LIFT NORTHWARD TOWARDS THE CWFA INTO THE LATE AFTERNOON HOURS.
MOISTURE CONVERGENCE ALONG THIS BOUNDARY WILL PROVIDE A FOCUS FOR
CONVECTION ACROSS THE NC/SC PIEDMONT WHERE STEEPENING LAPSE RATES
AND INCREASED MOISTURE YIELD SBCAPE VALUES IN EXCESS OF 1500J/KG.
THUS WILL FAVOR LOW END CHANCE LEVEL POPS ACROSS THE PIEDMONT...AND
ALSO ALONG THE HIGH TERRAIN WHERE EAST SOUTHEAST UPSLOPE FLOW AIDS
CONVECTION. SLIGHT CHANCE POPS WILL OVERSPREAD THE REMAINDER OF THE
FORECAST AREA BEFORE DIURNAL COOLING WARRANTS TAPERED POPS ACROSS
THE ENTIRE REGION FOR THE OVERNIGHT.
SURFACE HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS THE NORTHEAST
INTO THE WEEKEND...AND WILL EXTEND SOUTHWARD INTO THE
SOUTHERN/CENTRAL APPS. THIS COMBINED WITH RISING HEIGHTS ALOFT
WILL LIMIT CONVECTION EARLY ON SATURDAY BEFORE WEAK CIN IS OVERCOME
BY HEATING. EXPECTING INITIATION TO OCCUR ACROSS THE HIGH TERRAIN
ON SATURDAY AFTERNOON BEFORE WEAK NW FLOW ALOFT PROPAGATES SHOWERS
AND THUNDERSTORMS SOUTHEAST INTO THE FOOTHILLS/PIEDMONT REGIONS OF
NC/SC. DIURNALLY FAVORED LOW/MID LEVEL CHANCE POPS WILL HIGHLIGHT
THE FORECAST FOR SATURDAY. TEMPERATURES THROUGH THE SHORT TERM
PERIOD WILL BE AT OR JUST SLIGHTLY BELOW CLIMO.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 245 PM EDT TUE...THE LATEST GLOBAL MODELS CONTINUE TO INDICATE
THAT UPPER H5 HEIGHTS WILL FALL ACROSS THE SOUTHEAST SAT NIGHT INTO
SUN AS AN UPPER RIDGE OF HIGH AMPLIFIES OVER THE WESTERN CONUS WHILE
AN UPPER LOW PRESSURE TROUGH APPROACHES THE GREAT LAKES REGION FROM
SOUTH CENTRAL CANADA. THIS TROUGH IS EXPECTED TO SWING ACROSS THE
EASTERN STATES MON THROUGH WED.
AT THE SURFACE...BERMUDA HIGH WILL PERSIST THROUGH SUN BEFORE
SHIFTING TO THE EAST BY EARLY MON AS A COLD FRONT APPROACHES FROM
THE NW. THE FRONT IS EXPECTED TO CROSS THE AREA THROUGH MON NIGHT
FOLLOWED BY ANOTHER FRONT ON TUE. THE FRONT WILL REMAIN SOUTH OF THE
AREA WED AS A CONTINENTAL HIGH BUILDS IN FROM THE NW. AS FOR OUR
SENSIBLE WEATHER...POPS REMAIN NEAR CLIMO EACH DAY GIVEN LITTLE TO
NO CAPPING ALOFT AND SEASONABLY UNSTABLE AIRMASS DURING THE PEAK
HEATING HOURS. TEMPERATES WILL REMAIN NEAR...OR A FEW DEGREES BELOW
NORMAL THROUGH THE PERIOD.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AT CLT...A COMPLEX OF SHOWERS IS LIFTING NORTH OF THE TERMINAL EARLY
THIS MORNING...WHILE ADDITIONAL SCATTERED SHOWER ACTIVITY DEVELOPING
30 MILES OR SO SW OF THE AIRFIELD HAS STRUGGLED TO MAINTAIN ITSELF
UNDER WANING INSTABILITY. WHILE I CAN/T RULE OUR A SHOWER PASSING
NEAR THE TERMINAL FOR THE DURATION OF THE EARLY MORNING...FEEL THAT
A VCSH MENTION SHOULD BE SUFFICIENT. OTHERWISE...A TYPICALLY COMPLEX
JULY POST-CONVECTIVE FORECAST FOR THIS PERIOD...WITH A MYRIAD OF
COMPETING ISSUES RE: THE FOG/LOW STRATUS POTENTIAL FOR LATER THIS
MORNING. KCLT DID SEE SOME RAIN LAST EVENING...ALBEIT NOT VERY HEAVY
RAIN. HOWEVER...MANY AREAS WITHIN 10 MILES OF THE TERMINAL SAW A
VERY GOOD SOAKING...AND EXPECT PATCHES OF FOG AND/OR LOW STRATUS TO
DEVELOP WITHIN THESE AREAS TOWARD DAYBREAK...WITH THE POTENTIAL FOR
SOME IFR OR LOWER CIGS TO WAFT OVER KCLT. I THINK THIS IS ENOUGH OF
A LOW PROBABILITY EVENT TO MAINTAIN A TEMPO FOR A SCT IFR DECK...
ALONG WITH 3SM DURING THE PRE-DAWN HOURS. OTHERWISE...WITH WEAK COLD
FRONT SETTLING INTO THE AREA...AND PLENTY OF MOISTURE LINGERING...
EXPECT SCT TO NUMEROUS CONVECTIVE CELLS TO REDEVELOP THU
AFTERNOON...WARRANTING A PROB30 MENTION BY EARLY AFTERNOON...AND
CATEGORICAL TSRA BY MID-AFTERNOON OR SO.
ELSEWHERE...THE MAIN CONCERN WILL BE THE FOG/LOW STRATUS POTENTIAL
AT KAVL...WITH A BIT OF A LESSER CONCERN AT KHKY. KAVL HAS RECEIVED
QUITE THE SOAKING IN THE PAST FEW HOURS...AND DESPITE THE EXTENSIVE
MID/HIGH CLOUDS PERSISTING OVER THE AREA...IT SEEMS LIKELY THAT AS A
RESULT OF THE WET GROUND...IFR OR SUB-IFR CONDITIONS WILL DEVELOP
TOWARD DAYBREAK. KHKY HAS ALSO RECEIVED HEAVY RAINFALL RECENTLY...SO
HAVE OPTED TO INCLUDE A TEMPO FOR 2SM THERE AS WELL. OTHERWISE...THE
UPSTATE SC TERMINALS ARE EXPECTED TO REMAIN MVFR...EXCEPT FOR
PERHAPS A BRIEF VISBY RESTRICTION AT KAND TOWARD DAYBREAK.
OTHERWISE...WITH WEAK COLD FRONT SETTLING INTO THE AREA...AND PLENTY
OF MOISTURE LINGERING... EXPECT SCT TO NUMEROUS CONVECTIVE CELLS TO
REDEVELOP THU AFTERNOON...WARRANTING A PROB30/VCTS MENTION BY EARLY
AFTERNOON...AND CATEGORICAL TSRA BY MID-AFTERNOON OR SO.
OUTLOOK...SCATTERED MAINLY AFTN THUNDERSTORMS WILL CONTINUE THROUGH
LATE WEEK INTO THE WEEKEND AS HIGH PRESSURE SLOWLY SETTLES OVER THE
AREA. ANY RESTRICTIONS SHOULD MAINLY BE CONFINED TO DIURNAL TSTMS
AND MORNING VALLEY FOG EACH DAY.
CONFIDENCE TABLE...
06-12Z 12-18Z 18-24Z 00-06Z
KCLT HIGH 91% HIGH 100% HIGH 98% HIGH 100%
KGSP HIGH 95% HIGH 91% HIGH 100% HIGH 100%
KAVL MED 75% MED 68% HIGH 100% HIGH 95%
KHKY HIGH 91% HIGH 95% HIGH 100% HIGH 95%
KGMU HIGH 95% HIGH 91% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 95% 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...JOH
NEAR TERM...JDL/LG/NED
SHORT TERM...WIMBERLEY
LONG TERM...JOH/WIMBERLEY
AVIATION...JDL
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
343 PM CDT THU JUL 10 2014
.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT
SHORT WAVE TROUGH CLOUD COVER AND SCATTERED LIGHT SHOWERS HAVE
LESSENED THE BUILDUP OF INSTABILITY ACROSS THE REGION LATE THIS
AFTERNOON. THE SPC ANALYSIS SHOWED ONLY 500 TO 1500 J/KG OF MIXED
LAYER CAPE FROM NORTH TO SOUTH ACROSS THE CWA LATE THIS AFTERNOON.
ALTHOUGH...THE DEEP LAYER SHEAR WAS IMPRESSIVE UP TO OVER 50
KNOTS. EXPECT SOME MORE BUILDUP OF INSTABILITY INTO THE EVENING
ACROSS THE CWA AS CLOUDS AND LIGHT SHOWERS MOVE EAST. THE GFS AND
HI-RES MODELS STILL SHOWING NUMEROUS SHOWERS/STORMS DEVELOPING
MAINLY ACROSS THE EASTERN CWA THIS EVENING. CENTRAL SD ALSO SEEING
MORE SUNSHINE AND WARMING LATE THIS AFTERNOON. WITH AN INCREASING
85H LLJ ACROSS MAINLY THE EAST THIS EVENING...EXPECT A GOOD CHANCE
OF SHOWERS/STORMS ACROSS THIS REGION. INCREASED POPS THIS EVENING.
THE MODELS THEN SHOW A WEAK BOUNDARY DROPPING SLOWLY SOUTHEAST
TONIGHT AND FRIDAY BRINGING WINDS AROUND TO THE EAST AND NORTHEAST
ACROSS MOST OF THE CWA. AFTER THE CONVECTION TONIGHT...EXPECT MOST
OF FRIDAY TO NOW BE DRY ACROSS THE CWA. THE MODELS THEN SHOW
ANOTHER SHORT WAVE TROUGH FROM THE NORTHWEST DROPPING ACROSS THE
CWA FRIDAY NIGHT AND SATURDAY ALONG WITH A GOOD JET STREAK
DEVELOPING TO OUR NORTH AND NORTHEAST. THIS WILL PUT US IN THE
FAVORABLE RR QUADRANT. THUS...HAVE IN CHANCES OF MAINLY ELEVATED
SHOWERS/STORMS FOR FRIDAY NIGHT AND SATURDAY WITH EVERYTHING
MOVING OFF TO THE SOUTHEAST SATURDAY NIGHT. HIGHS WILL BE IN THE
80S ON FRIDAY AND A FEW DEGREES COOLER ON SATURDAY.
.LONG TERM...SUNDAY THROUGH THURSDAY
SUNDAY SHOULD PROVE TO BE THE WARMEST DAY OF THE EXTENDED FORECAST
PERIOD...WITH ANOMALOUSLY COOL AIR ADVECTING DOWN INTO THE CWA
MONDAY AND STICKING AROUND THROUGH PROBABLY WEDNESDAY...AT LEAST.
THIS SHOULD SPELL SOME MUCH BELOW NORMAL TEMPERATURES THROUGHOUT
THE PERIOD AND DRY CONDITIONS THROUGHOUT THE PERIOD. COLD AIR
INSTABILITY CU/STRATO-CU WILL LIKELY ONLY ADD INSULT TO INJURY ON
MONDAY CLOUDING THINGS UP AND KEEPING JULY INSOLATION FROM TAKING
THE EDGE OFF THE COLDNESS OF THE AIR ON MONDAY.
&&
.CLIMATOLOGICALLY...
AN ANOMALOUSLY COLD LOW PRESSURE SYSTEM WILL MOVE INTO UPPER
MIDWEST EARLY NEXT WEEK. THE COMBINATION OF A COOL CANADIAN
AIRMASS ALONG WITH INCREASING CLOUDS AND A CHANCE FOR SHOWERS
COULD RESULT IN A FEW RECORD LOW HIGH TEMPERATURES ON MONDAY.
BELOW IS A LIST OF LOCATIONS THAT COULD SEE NEAR RECORD COLD
READINGS ON MONDAY:
...LOCATION......FORECAST....RECORD LOW HIGH TEMP...
WHEATON MN 64 72 IN 1949
SISSETON 65 70 IN 1993
WATERTOWN 65 61 IN 1962
ABERDEEN 67 65 IN 1962
MOBRIDGE 69 64 IN 1962
PIERRE 72 65 IN 1989
&&
&&
.AVIATION...
18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
A RETURN FLOW SURFACE PRESSURE PATTERN WILL KEEP WINDS SOUTH-
SOUTHEAST OVER MUCH OF THE TAF VALID PERIOD AT KABR/KATY. A COLD
FRONT APPROACHING FROM THE NORTHWEST SHOULD BEGIN TO SWITCH WINDS
AROUND TO NORTH-NORTHEAST AT KPIR/KMBG BY FRIDAY MORNING. SOME OF
THE AVAILABLE GUIDANCE SUGGESTS PREVAILING VFR CONDITIONS MAY DIP
INTO MVFR/IFR FLT CATEGORY /PARTICULARLY AT KATY/ DUE TO POSSIBLE
LOW CIGS LATER TONIGHT INTO FRIDAY MORNING GIVEN THE AMOUNT OF
AVAILABLE LOW LEVEL MOISTURE. IF THUNDERSTORMS DEVELOP EARLY THIS
EVENING AND RUMBLE OVER KABR/KATY...THE LIKELIHOOD OF LOW CIGS
DEVELOPING LATE TONIGHT/EARLY FRIDAY MORNING BEGINS TO INCREASE.
THERE IS ALSO A CHANCE OF THUNDERSTORMS DEVELOPING BY EARLY THIS
EVENING ALONG THIS APPROACHING COLD FRONT...AS WELL AS IN THE LEE
OF THE BLACK HILLS SURFACE LOW...WHICH COULD REACH ALL THE WAY TO
KMBG/KPIR BEFORE FIZZLING OUT. HOWEVER...THE KMBG/KPIR TERMINALS
STAND A BETTER CHANCE OF REMAINING VFR THROUGH THE ENTIRE TAF
VALID PERIOD.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
SHORT TERM...MOHR
LONG TERM...DORN
AVIATION...DORN
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
1211 PM CDT THU JUL 10 2014
.UPDATE...
A PREVIOUSLY DIMINISHING MCS OVER EASTERN OK WAS BEGINNING TO
REORGANIZE AS IT MOVED INTO NORTHWEST AR A MIDDAY. HRRR SUGGESTS
CONVECTION WILL CONTINUE INTO CENTRAL AR... BEFORE DIMINISHING
OVER THE EAST AR DELTA BY 8 PM.
GIVEN THAT THE HRRR IS A LITTLE BEHIND ON THE EASTWARD PROGRESS
OF THE MCS... HAVE ADDED A SLIGHT CHANCE OF THUNDERSTORMS TO
PORTIONS OF EAST AR LATE THIS AFTERNOON INTO EARLY EVENING.
PWB
&&
.PREV DISCUSSION... /ISSUED 1153 AM CDT THU JUL 10 2014/
UPDATE...
UPDATED TO INCLUDE THE 18Z AVIATION DISCUSSION BELOW.
JCL
PREV DISCUSSION... /ISSUED 429 AM CDT THU JUL 10 2014/
CURRENTLY... AS OF 4AM...TEMPERATURES RANGE FROM THE MID 60S TO
LOWER 70S ACROSS THE MID-SOUTH. THE AREA IS FREE OF RAIN FOR THE
MOMENT...WITH PATCHY FOG ACROSS THE MAJORITY OF THE REGION.
SHOWERS AND THUNDERSTORMS ARE PASSING JUST TO THE SOUTH OF THE
FORECAST AREA ALONG A WEAK CONVERGENCE ZONE OVER THE ARKLATEX
REGION. FURTHER UPSTREAM...AN MCS IS DIVING SOUTHEAST ACROSS
KANSAS AND NORTHERN OKLAHOMA. DEWPOINTS HAVE LOWERED SLIGHTLY
ACROSS THE NORTHERN TIER OF THE CWA...HOWEVER READINGS ARE STILL
IN THE UPPER 60S AND LOWER 70S ACROSS MOST OF THE AREA AS THE
FRONTAL BOUNDARY HAS PRETTY MUCH WASHED OUT.
SHORT TERM...TODAY THROUGH SATURDAY...
A FEW SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON
OVER SOUTHERN PORTIONS OF THE FORECAST AREA. THIS AREA WILL HAVE
THE BEST COMBINATION OF LOW LEVEL MOISTURE AND INSTABILITY
ALLOWING FOR A FEW DAYTIME SHOWERS TO POP UP. THE REST THE OF THE
REGION WILL REMAIN DRY AS SURFACE HIGH PRESSURE BUILDS IN FROM THE
NORTH. IT SHOULD BE A NICE DAY ACROSS THE REGION WITH MOSTLY CLEAR
SKIES AND TEMPERATURES IN THE UPPER 80S TO AROUND 90 DEGREES.
FRIDAY AND SATURDAY WILL BE MOSTLY DRY AS A WEAK UPPER LEVEL
RIDGE BUILDS IN OVER THE MID-SOUTH. EXPECT TEMPERATURES TO BE NEAR
OR SLIGHTLY ABOVE SEASONAL READINGS IN THE LOWER TO MID 90S DURING
THE DAY. A STRAY SHOWER OR THUNDERSTORM CANNOT BE TOTALLY RULED
OUT DUE TO THE HOT AND HUMID AIRMASS...BUT DECIDED TO LEAVE MENTIONABLE
POPS OUT OF THE FORECAST AS CHANCES WILL BE ISOLATED AT BEST.
LONG TERM...SUNDAY THROUGH MIDDLE OF NEXT WEEK...
BY SUNDAY...SURFACE HIGH PRESSURE WILL SHIFT TO THE NORTHEAST AND WINDS
WILL TURN AROUND TO THE SOUTH DRAMATICALLY INCREASING LOW LEVEL
MOISTURE OVER THE REGION. THE LONGWAVE TROUGH THAT HAS RESIDED
OVER THE EASTERN TWO THIRDS OF THE COUNTRY FOR THE LAST FEW DAYS
WILL SHIFT BACK SOUTH INTO OUR AREA. HEIGHT FALLS WILL BEGIN TO
TAKE PLACE LATE SUNDAY NIGHT INTO MONDAY AFTERNOON TRIGGERING A
FEW SHOWERS AND THUNDERSTORMS OVER THE NORTHERN PORTION OF THE
FORECAST AREA.
BY MONDAY NIGHT...MODEL GUIDANCE IS IN PRETTY GOOD AGREEMENT ON A
COLD FRONT DROPPING INTO THE MID-SOUTH FROM THE NORTHWEST. TIMING
AND THE POSSIBILITY OF SEVERE WEATHER IS STILL A LITTLE
QUESTIONABLE BEING NEARLY FIVE DAYS OUT. FOR NOW...IT APPEARS THAT
THE FRONTAL PASSAGE LOOKS PRETTY SIMILAR TO WHAT WE HAD THIS PAST
TUESDAY EXCEPT FOR MUCH COOLER AIR BEHIND IT.
REST OF THE WEEK...NORTHWEST FLOW ALOFT WILL CONTINUE TO DOMINATE
THE WEATHER PATTERN THROUGH THE END OF THE WEEK...EFFECTIVELY
KEEPING THE MID-SOUTH WET WITH BELOW NORMAL TEMPERATURES.
AC3
&&
.AVIATION...
18Z TAF CYCLE (10/18Z-11/18Z)
VFR CONDITIONS WILL PREVAIL DURING THE PERIOD...THE EXCEPTION WILL
BE MVFR VISIBILITIES IN FOG AT KMKL AND KTUP 11/08Z-11/12Z. LIGHT
WINDS WILL OCCUR DURING THE PERIOD.
JCL
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS BLACKSBURG VA
114 AM EDT THU JUL 10 2014
.SYNOPSIS...
A SLOW MOVING COOL FRONT WILL SLIDE SOUTHEAST ACROSS THE REGION
OVERNIGHT BEFORE STALLING ACROSS NORTHERN NORTH CAROLINA THURSDAY.
WEAK AREAS OF LOW PRESSURE RIDING ALONG THE FRONT WILL KEEP
UNSETTLED WEATHER GOING INTO LATE THURSDAY BEFORE WEAK HIGH
PRESSURE SPILLS SOUTH INTO THE REGION FOR FRIDAY AND SATURDAY.
DEEPER MOISTURE WILL RETURN LATER IN THE WEEKEND AND EARLY NEXT
WEEK AHEAD OF A MUCH STRONGER COLD FRONT THAT WILL BE PASSING
THROUGH THE REGION BY NEXT TUESDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 1250 AM EDT THURSDAY...
SENT AN UPDATE TO RAISE POPS TO HIGH CHANCE/LIKELYS ACROSS THE SW
AHEAD OF THE NEXT WAVE OF CONVECTION SEEN HEADING NE INTO NW NC.
LATEST HRRR SPREADS THIS PRECIP NE INTO SOUTHERN VA AND PERHAPS
EVEN OUT INTO THE PIEDMONT LATE PENDING HOW MUCH SURVIVES
STABILITY OUT EAST. THUS ALSO INCLUDING CHANCE POPS SOUTHERN TIER
DURING THE NEXT FEW HOURS MORE IN LINE WITH THE LATEST 4KM NAM.
WILL KEEP SOME THUNDER MENTION AS WELL GIVEN LINGERING CAPE SEEN
FEEDING INTO NW NC ATTM...BUT THINK SHOULD SEE DEEPER CONVECTION
FADE IN THE NEXT COUPLE OF HOURS WITH MORE OF A HEAVY RAIN
SCENARIO.
AS OF 955 PM EDT WEDNESDAY...
SHOWERS AND ISOLATED STORMS HAVE WEAKENED. STILL GOING TO SEE A
THREAT ALONG A BOUNDARY STRETCHED FROM ERN KY SOUTHEAST TOWARD
NC/VA OVERNIGHT. WILL KEEP THE ISOLATED/LOW CHANCE THREAT HERE
WHILE HAVING IT MAINLY DRY ELSEWHERE. PATCHY FOG EXPECTED AS WELL
WHERE SKIES CLEAR OUT SOME WHICH FAVORS THE NW CWA. NOT MUCH
CHANGE TO THE OVERNIGHT FORECAST IN TERMS OF TEMPS.
PREVIOUS VALID DISCUSSION...
OVERNIGHT DRIER AIR AS SEEN ON THE WATER VAPOR LOOP WILL PUSH
INTO THE REGION AS THE LEADING WEAK COLD FRONT DRIFTS SOUTH INTO
NORTH CAROLINA AND STALLS. MODELS CONTINUED TO SHOW A LOW ALONG
THE FRONT LATE TONIGHT THAT PUSHES THE DEEPER MOISTURE BACK INTO
THE FORECAST AREA AFTER MIDNIGHT. HAVE A LULL IN THE
PRECIPITATION... ESPECIALLY IN THE NORTHWEST HALF OF THE FORECAST
AREA THIS EVENING...THEN BRING BETTER PROBABILITIES BACK IN BY
MORNING.
TEMPERATURES WILL DEPEND ON CLOUD COVER. WITH LITTLE DROP IN DEW
POINTS TONIGHT MINIMUM TEMPERATURES WILL REMAIN MILD. IF CLEARING
DOES OCCUR...MAY BE ADDING FOG BACK INTO THE FORECAST IN LOCATIONS
THAT HAD RAIN THIS AFTERNOON. CLOUDS AND SHOWERS WILL ALSO LIMIT
RISE IN TEMPERATURES...ESPECIALLY ACROSS THE SOUTH AND EAST ON
THURSDAY. STAYED CLOSER TO COOLER SIDE OF GUIDANCE FOR MAXIMUM
TEMPERATURES.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
AS OF 300 PM EDT WEDNESDAY...
EXPECT AN AREA OF PRECIPITATION TO BE COVERING THE SOUTHEAST PORTION
OF THE BLACKSBURG CWA AT THE START OF THE SHORT TERM PERIOD...WITH
GOOD LOW LEVEL MOISTURE CONVERGENCE ALONG A SFC BOUNDARY IN THIS
AREA. THIS REGION WILL ALSO FALL UNDER THE RIGHT REAR QUAD OF AN
UPPER LEVEL AND GOOD UPPER LEVEL DIVERGENCE.THIS AREA OF PRECIP WILL
GRADUALLY WANE DURING THE OVERNIGHT HOURS.
FOR FRIDAY...THE UPPER LEVEL TROF AXIS WEAKENS AND SHIFTS SLIGHT
EAST...PLACING THE BEST UPPER LEVEL SUPPORT EAST OF THE BLACKSBURG
FORECAST AREA. STILL EXPECT WIDELY SCATTERED SHOWERS AND STORMS IN
THIS AREA WITH WEAK CONVERGENCE ALONG THE DYING BOUNDARY. A
SECOND AREA FOR PRECIP DEVELOPMENT WILL BE POSSIBLE IN THE
MOUNTAINS...WITH AN UPSLOPE FLOW AND A SFC BOUNDARY FORECAST BY
THE GFS/NAM/SREF/ECMWF NEAR THE VA/WV BORDER.
AS THE DEEPEST MOISTURE AND BEST UPPER LEVEL SUPPORT SHIFT
EAST...THE COVERAGE OF PRECIPITATION FRIDAY SHOULD BE LESS...AS WELL
AS THE AMOUNT OF CLOUD COVER. GENERALLY FOLLOWED THE GFS MOS
GUIDANCE FOR HIGHS WITH HAS PERFORMED THE BEST IN OUR AREA OVER THE
PAST FEW DAYS.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 245 PM EDT WEDNESDAY...
AS SFC HIGH PRESSURE SHIFTS EAST ON SATURDAY...THE LOW LEVEL FLOW
BECOMES EAST/SOUTHEAST BRINGING WEAK UPSLOPE FLOW. AT THIS
POINT...THE DEEPEST MOISTURE WILL BE SOUTH AND EAST OF OUR
AREA...BUT ENOUGH LOW LEVEL CONVERGENCE SHOULD SPARK ISOLATED/WIDELY
SCATTERED SHOWERS/STORMS ACROSS THE SOUTHERN BLUE RIDGE.
BY SUNDAY AND MONDAY...A LOW LEVEL THETA-E AXIS SURGES INTO OUR AREA
WHICH WILL INCREASE COVERAGE OF DIURNALLY DRIVEN SHOWERS AND
STORMS. BUT SIMILAR TO WHAT WE HAVE EXPERIENCED RECENTLY...A DEEP
WEST/SOUTHWEST FLOW SHOULD KEEP THE CONVECTION SCATTERED.
TOWARD THE END OF THE LONG TERM PERIOD THE MEDIUM RANGE MODELS
CONTINUE TO FORECAST A BROAD UPPER TROF AND AN ASSOCIATED CUT OFF
LOW OVER THE NORTHERN GREAT LAKES BY TUESDAY. THIS FEATURE HELPS
DRIVE A COLD FRONT THROUGH OUR AREA ON TUESDAY. THERE ARE STILL
DIFFERENCES WITH REGARD TO THE TIMING OF THIS FRONT...WITH THE 06Z
GFS FASTER THAN THE 00Z ECMWF. USING A BLEND OF THESE
SOLUTIONS...WILL CONTINUE TO CARRY A CHANCE OF SHOWERS/STORMS ON
TUESDAY.
TEMPERATURES SHOULD CLIMB IN ADVANCE OF THE FRONT TO NEAR OR
SLIGHTLY ABOVE NORMAL...BEFORE FALLING BELOW NORMAL TUESDAY NIGHT
INTO WEDNESDAY WHEN DRIER AIR ARRIVES.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 100 AM EDT THURSDAY...
COMMS ISSUES REMAIN AT KDAN DESPITE AN INTERMITTENT RETURN OF
OBSERVATION DATA. AMD NOT SKED CONTINUED IN THE TAF.
BATCH OF SHRA/TSRA HEADING NE INTO NW NC WILL BE THE MAIN CONCERN
OVERNIGHT OUTSIDE OF DENSE FOG/STRATUS IN AREAS THAT SAW EARLIER
HEAVY RAIN. EXPECT SOME OF THE SHOWERS TO THE SW TO LIKELY AFFECT
KDAN AND PERHAPS AS FAR NORTH AS THE KBLF-KROA CORRIDOR THROUGH
ABOUT 09Z/5AM...THEN NE TO AROUND KLYH BEFORE DAWN. THEREFORE HAVE
INCLUDED A VCSH MENTION IN THESE SPOTS OR A FEW TEMPO HOURS FOR
REDUCED VSBY IN BOTH SHRA/FOG OVERNIGHT. OTRW FOG SHOULD BECOME
AN ISSUE AT TIMES OVERNIGHT ESPECIALLY WHERE IT RAINED...WHICH
WILL BE ALL SITES. ATTM...THE FOG WILL ALSO BE DEPENDENT ON
CLOUDS. THINK ENOUGH BREAKS TO ALLOW FOG FORMATION. WILL GO MAINLY
MVFR/IFR LATE TONIGHT BUT NOT AS WIDESPREAD AS EARLIER GIVEN
THICKER CLOUD CANOPY HEADING UP FROM THE SW.
FOG WILL FADE BY MID MORNING EXCEPT IN AREAS OVER THE EAST THAT
MIGHT STILL BE SEEING SOME SHRA BANDS LINGER. APPEARS CIGS WILL
ALSO BE SLOWER TO LIFT GIVEN SO MUCH MOISTURE AROUND SO INCLUDED
MORE LOW END VFR BASES AT MOST SPOTS DURING THE MORNING BEFORE
BREAKING OUT TO A 4-5K CU FIELD AFTER MIDDAY. KDAN MAY BE THE
EXCEPTION WHERE LOWER CIGS LINGER BEFORE MORE SHRA/TSRA DEVELOPS.
MODELS KEEPING THE THREAT OF SHRA/TSRA AROUND OVER THE SOUTHEAST
CWA THURSDAY...SO KEPT VCTS AT ROA/LYH/DAN...AND ADDED AT KBCB
WITH A VCSH AT KBLF/KLWB PER SLOWNESS OF THE FRONT TO PUSH SE AND
LINGERING LOW LEVEL MOISTURE WITH HEATING WHICH SHOULD BE BETTER
OVER THE WEST/NW. OTRW EXPECT VFR OUTSIDE OF ANY STORMS FOR THE
MOST PART.
WAVE SHOULD FINALLY TAKE THE NEXT ROUND OF SHRA/TSRA TO THE SE
THURSDAY EVENING WITH PERHAPS ENOUGH DRYING TO END CONVECTION AT
ALL LOCATIONS AFTER MIDNIGHT.
EXTENDED AVIATION...
A LOWER PROBABILITY OF PRECIPITATION IS EXPECTED ACROSS THE AREA
ON FRIDAY AND SATURDAY AS WEAK HIGH PRESSURE SLIDES IN FROM THE
NORTH.
MOISTURE AND MORE WIDESPREAD SHRA/TSRA LIKELY TO RETURN FOR THE
END OF THE WEEKEND AS THE FRONT RETURNS NORTH RESULTING IN PERIODS
OF MVFR CONDITIONS. OTRW PATCHY FOG RESULTING IN LOCAL MVFR TO IFR
CONDITIONS LIKELY DURING THE LATE NIGHTS AND EARLY MORNINGS ESPCLY
VALLEY LOCATIONS AND WHERE EARLIER AFTERNOON RAINFALL OCCURRED.
&&
.EQUIPMENT...
AS OF 100 AM EDT THURSDAY...
COMMUNICATIONS OUTAGE CONTINUES WITH KDAN ASOS NOT TRANSMITTING.
THE FAA IS AWARE OF THE OUTAGE AND WILL BE WORKING ON IT...BUT NO
ESTIMATED TIME OF WHEN IT WILL BE WORKING AGAIN.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS/JH
NEAR TERM...AMS/JH/WP
SHORT TERM...PH
LONG TERM...AMS/PH/WERT
AVIATION...AMS/JH/WP
EQUIPMENT...WP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
608 PM CDT FRI JUL 11 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 332 PM CDT FRI JUL 11 2014
MAIN FORECAST CONCERNS ARE ON SEVERE THUNDERSTORM POTENTIAL ON
SATURDAY INTO SATURDAY EVENING. FOCUS THEN TURNS TO UNSEASONABLY
COLD TEMPERATURES EARLY NEXT WEEK.
SURFACE OBSERVATIONS SHOWED A COLD FRONT EXTENDING FROM NORTHWEST
MINNESOTA INTO EXTREME NORTHEAST SOUTH DAKOTA...EDGING SOUTHEAST.
A BROAD WARM AIR ADVECTION REGIME WAS IN PLACE OVER THE UPPER
MISSISSIPPI RIVER VALLEY WITH A SHORTWAVE MOVING THROUGH AND
EXITING THE AREA LATE THIS AFTERNOON . THIS WAVE BROUGHT SHOWERS
AND ISOLATED THUNDERSTORMS TO PARTS OF THE REGION TODAY. A WARM
FRONT IS EXPECTED TO LIFT INTO CENTRAL IOWA/NORTHERN ILLINOIS
TONIGHT AND WILL BE THE FOCUS FOR MORE SHOWERS AND THUNDERSTORMS.
ACROSS THE LOCAL AREA IT SHOULD BE PRETTY QUIET TONIGHT OUTSIDE
OF SEEING MOSTLY CLOUDY SKIES AND POSSIBLY SOME PATCHY FOG. THE
CLOUD COVER AND SOUTH WINDS SHOULD HELP HOLD TEMPERATURES IN THE
MID TO UPPER 60S.
A SHORTWAVE ROUGH THEN RACES EAST ACROSS SOUTH DAKOTA EARLY SATURDAY
MORNING AND PUSHES THROUGH THE FORECAST AREA LATE SATURDAY MORNING
THROUGH SATURDAY AFTERNOON. THIS WAVE WILL INTERACT WITH THE COLD
FRONT EDGING INTO THE FORECAST AREA FROM THE NORTHWEST AND THE WARM
FRONT OVER PORTIONS OF NORTHERN IOWA INTO FAR SOUTHWEST WISCONSIN.
WHILE THIS FEATURE WILL GENERATE WIDESPREAD SHOWERS AND
THUNDERSTORMS OVER THE REGION THERE IS SOME UNCERTAINTY REGARDING
SEVERE WEATHER POTENTIAL. THE MAIN CONCERN LOOKS TO BE HEAVY RAIN
THROUGH MIDDAY ON SATURDAY THEN...IF THE INSTABILITY CAN LIFT
NORTH INTO LOCATIONS ALONG AND SOUTH OF INTERSTATE 90...WE COULD
SEE THE THREAT FOR DAMAGING WINDS AND LARGE HAIL. WHILE 0-1 KM
SHEAR ISN/T IMPRESSIVE...IT COULD POSSIBLY BE ENHANCED OVER
PORTIONS OF NORTHEAST IOWA AND EXTREME SOUTHWEST WISCONSIN CLOSER
TO WARM FRONT. THIS WOULD LEAD TO THE POSSIBILITY OF AN ISOLATED
TORNADO OVER THESE AREAS. THERE IS EXCELLENT UPPER LEVEL SUPPORT
FOR SHOWERS AND THUNDERSTORMS TOMORROW THANKS TO THE RIGHT
ENTRANCE REGION OF AN UPPER JET STREAK POSITIONED OVER THE
REGION SO HAVE INCREASED PRECIPITATION CHANCES SIGNIFICANTLY. 0-6
KM BULK SHEAR IS WEAK SATURDAY MORNING BUT THEN RAMPS UP SATURDAY
AFTERNOON WHEN VALUES INCREASE TO 40 TO 50 KTS. MOST OF THE SHEAR
IS LOCATED IN THE 1 TO 7 KM LAYER...SO EVEN ELEVATED STORMS COULD
POSSIBLY BECOME SEVERE. PRECIPITABLE WATER VALUES INCREASE TO 1.5
TO 2.0 INCHES TONIGHT OVER MUCH OF THE FORECAST AREA AND REMAIN IN
THIS RANGE THROUGH TOMORROW AFTERNOON FOR LOCATIONS ALONG AND
SOUTH OF INTERSTATE 90. THESE PW VALUES COMBINED WITH WARM CLOUD
DEPTH OF 3.5 TO 4 KM WILL INCREASE THE POTENTIAL FOR HEAVY
RAINFALL. WILL HAVE TO KEEP A CLOSE EYE ON HEAVY RAIN POTENTIAL
OVER NORTHEAST IOWA INTO SOUTHWEST WISCONSIN. THE FRONT.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 332 PM CDT FRI JUL 11 2014
THE FRONT THEN PUSHES SOUTHEAST OF THE FORECAST AREA SATURDAY
EVENING WITH SHOWERS AND THUNDERSTORM ENDING. A SECONDARY COLD FRONT
THEN DROPS SOUTH ACROSS THE AREA ON SUNDAY AND MAY GENERATE A
COUPLE OF SHOWERS AND THUNDERSTORMS BUT INSTABILITY IS RATHER
LACKING WITH THIS FEATURE. A POTENT UPPER TROUGH WILL DROP SOUTH
OUT OF CANADA AND INTO THE UPPER MISSISSIPPI RIVER VALLEY SUNDAY
NIGHT INTO MONDAY BRINGING UNSEASONABLY COLD AIR INTO THE REGION
ALONG WITH CHANCES FOR RAIN SHOWERS. 850 MB TEMPERATURES FALL TO
AROUND 4 C MONDAY NIGHT INTO TUESDAY WITH STANDARDIZED ANOMALIES
OF -2.0 TO -2.5 PLACING US IN RECORD COLD
TEMPERATURES...ESPECIALLY FOR HIGH TEMPERATURES ON MONDAY INTO
TUESDAY. TUESDAY LOOKS TO BE THE COLDEST DAY WHEN HIGHS WILL
STRUGGLE TO GET OUT OF THE LOWER TO MID 60S. THE TROUGH EXIT THE
REGION TUESDAY NIGHT INTO WEDNESDAY . TEMPERATURES THEN START TO
MODERATE WEDNESDAY THROUGH THE END OF THE WORK WEEK WITH HIGHS
CLIMBING BACK INTO THE 70S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 608 PM CDT FRI JUL 11 2014
BAND OF MVFR CLOUDS IS ADVANCING SOUTHEAST INTO THE AREA AHEAD OF
A WEAK COLD FRONT THAT WAS OVER CENTRAL MINNESOTA. EXPECT THESE
CLOUDS WILL HAVE OVERSPREAD KRST BY 00Z AND REACH KLSE BY THE
MIDDLE OF THE EVENING. NEITHER THE 11.18Z NAM OR 11.21Z RAP ARE
HANDLING THESE CLOUDS WELL AT ALL...BUT LOOKING AT SURFACE
OBSERVATIONS...WOULD TEND TO THINK THEY SHOULD SCATTER OUT AT
SOME POINT OVERNIGHT. IF THIS DOES OCCUR...IT WOULD SET UP THE
POTENTIAL FOR FOG TO DEVELOP WITH THE RAIN THAT FELL DURING THE
DAY PROVIDING ENOUGH LOW LEVEL MOISTURE FOR SATURATION TO OCCUR.
HAVE ADDED IN THIS FOG POTENTIAL WITH IFR VISIBILITIES FOR LATE
TONIGHT. THE FOG AND MVFR CEILINGS SHOULD THEN LIFT BY MID MORNING
SATURDAY. A SHORT WAVE TROUGH ADVANCING OUT OF THE ROCKIES SHOULD
PUSH A ROUND OF CONVECTION TOWARD BOTH SITES SATURDAY AFTERNOON.
FOR NOW HAVE ADDED IN VCTS WITH VFR CEILINGS AND WILL HAVE TO ADD
MORE DETAIL WITH LATER FORECASTS.
&&
.CLIMATE...
ISSUED AT 332 PM CDT FRI JUL 11 2014
RECORD COOL HIGH TEMPERATURES ARE POSSIBLE ON TUESDAY AS AN
UNSEASONABLY COLD AIRMASS SETTLES OVER THE UPPER MISSISSIPPI
RIVER VALLEY. FORECAST HIGH TEMPERATURES FOR TUESDAY ARE 65 AT
ROCHESTER AND 66 AT LA CROSSE. THESE TEMPERATURES WOULD BREAK THE
RECORD LOWEST HIGH TEMPERATURES FOR JULY 15TH. THE OLD RECORDS ARE
68 AT LA CROSSE SET BACK IN 1962 AND 67 AT ROCHESTER ALSO SET
BACK IN 1962.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...04
CLIMATE...WETENKAMP
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
433 AM EDT SAT JUL 12 2014
.SHORT TERM /TODAY THROUGH SUNDAY/...
WEAK BOUNDARY STILL SITUATED ACROSS CENTRAL GA THIS MORNING. THE
BOUNDARY IS VERY DIFFUSE AND IS ONLY BARELY NOTED IN THE TEMP/DEW
FIELDS. REGIONAL RADAR SHOWS ALL THE EARLIER SHOWER ACTIVITY HAS
DIMINISHED ACROSS THE CWFA EARLY THIS MORNING.
POP COVERAGE SHOULD BE LESS TODAY THAN IN PREVIOUS DAYS. THE FRONT
WILL CONTINUE TO BECOME MORE DIFFUSE WHILE PUSHING SOUTHWARD AS HIGH
PRESSURE ACROSS THE MIDDLE ATLANTIC BUILDS DOWN THE SPINE OF THE
APPALACHIAN MOUNTAINS. WILL HAVE THE HIGHEST POPS IN THE SOUTHERN
QUARTER OF THE CWFA...NEAREST THE SURFACE BOUNDARY. IN
ADDITION...THE HRRR IS SHOWING SOME ISOLD/LOW END SCT DEVELOPMENT
ACROSS THE HIGHER TERRAIN THIS AFTERNOON.
PWATS ARE A LITTLE HIGHER THAN YESTERDAY...WITH THE DEEPEST MOISTURE
STILL SOUTH OF THE WEAKENING BOUNDARY. HOWEVER...WITH BL WINDS AT OR
BLO 15 KT...STORM MOVEMENT SHOULD BE SLOW. THIS MAY ALSO LEAD TO ANY
STORMS DEVELOPING ACROSS NE GA TO STAY LOCKED ON THE HIGHEST
TERRAIN...LEADING TO LOCALLY HEAVY RAINFALL.
DO THINK CONVECTION WILL MOSTLY BE DIURNAL IN NATURE...AND BEGIN
DIMINISHING WITH THE SETTING SUN. CONVECTION SHOULD BE PULSE...WITH
HIGH CAPE AND LOW SHEAR. MID LEVEL LAPSE RATES REMAIN WEAK...AND
CAN`T FIND ANY SIGNIFICANT SHORTWAVES IN THE FLOW. SO...WIDESPREAD
SEVERE THUNDERSTORMS ARE NOT ANTICIPATED...EITHER TODAY OR SUNDAY
BUT A FEW STRONG STORMS WILL HAVE THE POTENTIAL TO PRODUCE LOCALLY
HEAVY RAINFALL AND GUSTY WINDS. THERE IS A LITTLE POTENTIAL FOR AN
ISOLD SEVERE STORM EACH DAY. CONVECTIVE COVERAGE FOR SUNDAY SHOULD
BE EVEN LESS THAN TODAY.
WITH LESSER CONVECTIVE COVERAGE...TEMPS WILL BE WARMER.
NLISTEMAA
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
NO IMPACT WEATHER EXPECTED IN THE LONG TERM PERIOD. PATTERN STILL
EXPECTED TO BECOME DOMINATED BY LARGE UPPER TROUGH OVER THE ERN
CONUS BY TUES AND PERSIST THRU FRIDAY. 00Z MED RANGE MODEL
GUIDANCE AGAIN IN GOOD AGREEMENT. FRONT ASSOCIATED WITH LEADING
EDGE OF WESTERLIES TO MOVE INTO STATE ON TUES SO BUMPED POPS TO
LIKELY. AS MODEL GUIDANCE STARTS TO HONE IN ON SPECIFICS AND WITH
LESS WEIGHT ON CLIMATOLOGY...BEGINNING TO APPEAR THAT TUES/WED
WILL BE SIGNIFICANTLY DRIER AND MODERATELY COOLER THAN NORMAL
AFTER FROPA. WED MAX TEMPS MAY REMAIN IN THE 70S IN HIGHER
ELEVATIONS OF NORTH GA. DEWPOINTS SHOULD BE IN THE 50S. AS FRONT
WASHES OUT AND LIFTS NORTH THURS/FRI WILL LIKELY SEE RETURN TO SCT
DIURNAL SHOWERS AND THUNDERSTORMS. USED DYNAMIC BLEND FOR FORECAST
TEMPS WHICH WEIGHTS RAW MODELS AND UNCORRECTED MOS GUIDANCE IN AREAS
OF RAIN AND CLOUDS AND BIAS CORRECTED MOS GUIDANCE IN AREAS OF NO
RAIN AND LESS CLOUDS.
SNELSON
&&
AVIATION...
06Z UPDATE...
PATCHY FOG AND LOW CIGS ARE POSSIBLE TONIGHT IN PLACES WHERE
HEAVIER RAINFALL OCCURRED. HAVE KEPT CIGS SCT FOR NOW WITH TEMPO
BKN VALUES...BUT WILL MONITOR OBS IN CASE PREVAILING BKN/OVC IS
NEEDED. ANY LOW CLOUDS SHOULD LIFT TO DIURNAL CU LATER THIS
MORNING. SCT CONVECTION WILL AGAIN BE POSSIBLE OVER MUCH OF THE
AREA...AND KEPT THE PREVIOUS TIMING IN THE TAFS.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM CONFIDENCE ON CIGS/VSBYS OVERNIGHT. HIGH CONFIDENCE
REMAINING ELEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 91 71 93 70 / 30 30 20 10
ATLANTA 90 73 92 73 / 20 20 20 10
BLAIRSVILLE 85 66 86 63 / 30 30 30 10
CARTERSVILLE 91 71 93 69 / 20 20 20 10
COLUMBUS 92 74 94 73 / 30 30 20 10
GAINESVILLE 88 70 91 72 / 30 30 20 10
MACON 91 72 93 69 / 30 30 20 10
ROME 92 72 93 70 / 20 20 20 10
PEACHTREE CITY 90 71 92 69 / 20 20 20 10
VIDALIA 89 73 93 72 / 30 30 30 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...NLISTEMAA
LONG TERM....SNELSON
AVIATION...NLISTEMAA
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
429 AM CDT SAT JUL 12 2014
.DISCUSSION...
316 AM CDT
TODAY THROUGH TONIGHT...
MAIN FOCUS FOR TODAY CONTINUES TO REVOLVE AROUND CONVECTIVE
TIMING/COVERAGE AND INTENSITY. EARLY THIS MORNING AN AREA OF SHOWERS
WAS BEGINNING TO DEVELOP OVER THE CENTRAL/SOUTHERN PORTIONS OF THE
FORECAST AREA...MAINLY ASSOCIATED WITH WARM AIR ADVECTION. DEW PTS
WERE NUDGING UP TO THE MID 60S...WITH THE EXPECTED 70 DEG DEW PTS
JUST SOUTH/SOUTHWEST OF THE CWFA. PWAT VALUES LATER TDY ARE STILL
PROGGED TO NEAR 2"...AND THE LCL ARW8KM IS SUGGESTING THAT A FEW
POCKETS OF JUST OVER 2" PWAT VALUES FOR PORTIONS OF THE AREA SOUTH
OF I-80 LATE THIS AFTN/EARLY EVE. TEMPS TODAY WILL BE A
CHALLENGE...AS IF ANY BREAKS IN THE CLOUDS CAN OCCUR TEMPS COULD
NUDGE UP A FEW DEGREES. AT THIS TIME WILL MAINTAIN TEMPS IN THE LOW
TO NEAR MID 80S. WITH THE HIGH AMOUNT OF MOISTURE IN PARCELS...IT
WILL BE DIFFICULT FOR TEMPS TO SOAR AND LIKELY BE A SLOW DIURNAL
CURVE TDY. CONFIDENCE OF ANY BREAKS IN THE CLOUDS LOOKS
MINIMAL...AND MAY QUICKLY FILL BACK-IN.
THERE REMAINS A CONCERN ABOUT STRONG TO POSSIBLY SEVERE STORMS. THE
SPC CONTINUES TO HAVE THE ENTIRE FORECAST AREA OUTLOOKED FOR A
SLIGHT RISK OF SEVERE STORMS IN THE DAY 1. THE FOCUS FOR ACTIVITY
CONTINUES TO BE ALONG MOIST BOUNDARY THAT WILL EXTEND FROM CENTRAL
IOWA EAST THROUGH NORTHERN IL/NORTHWEST IN. GUIDANCE SOUNDINGS WOULD
SUGGEST RATHER UNIFORM WIND AT 30-40KTS...HOWEVER THIS IS ALL AHEAD
OF THE POTENT TROUGH THAT WILL BE STARTING TO DIG INTO THE UPPER
MIDWEST THIS EVENING. EXPECT AN MCS TO DEVELOP AND COULD BE SLOW
MOVING ACROSS THE REGION THIS EVENING.
THE PRESENCE OF A WARM LYR ALOFT WILL LIKELY
CAP THE CONVECTIVE COVERAGE UNTIL 21Z...THEN SHUD STEADILY DISSOLVE.
SO THE FOCUS FOR TIMING APPEARS TO BE MORE THIS EVENING INTO THE
OVERNIGHT HOURS. SEVERAL WEAK PIECES OF VORTICITY ARE PROGGED TO
SLIDE ALONG THE MOIST BOUNDARY AS IT SLOWLY SAGS SOUTH/SOUTHEAST
OVERNIGHT. THUS IT IS POSSIBLE SOME TRAINING OF STORMS MAY
OCCUR...AND GIVEN THE ANOMALOUSLY MOIST ENVIRONMENT FLOODING
CONCERNS COULD BE AN ISSUE.
LATE TONIGHT INTO EARLY SUN MORNING...THE BOUNDARY IS PROGGED TO BE
SLOWLY SLIDING SOUTHEAST ACROSS THE FORECAST AREA. GUIDANCE APPEARS
TO HAVE BEEN SLIGHTLY MORE PROGRESSIVE...AND COULD BRING AN END TO
THE CONVECTION A FEW HOURS AFT MIDNIGHT FOR THE NORTHWEST CWFA.
SUNDAY THROUGH MONDAY...
GUIDANCE HAS BEEN TRENDING DRY FOR MUCH OF THE DAY SUN...WITH WEAK
DIFFLUENCE NEAR THE SFC COVERING WISC/NORTHERN IL. LCL ARW8KM HAS
ALSO BEEN TRENDING DRY WITH THE LATEST CYCLES...SO CONFIDENCE HAS
INCREASED AND WILL LEVERAGE THIS WITH A DRY FORECAST SUN. THE
EXCEPTION WILL BE THE SOUTHERN CWFA WHERE THE BOUNDARY WILL STILL BE
RATHER CLOSE. THERMAL TEMPS WOULD STILL BE SUPPORTIVE OF A WARM
AFTN...SO HAVE HELD ONTO TEMPS IN THE LOW 80S SUN.
THE WEAK SFC RIDGE SHUD HOLD ACROSS THE REGION THRU THE EVE
HOURS...THEN BEGIN TO WEAKEN WITH THE MAIN FRONTAL BOUNDARY
APPROACHING FROM THE NORTHWEST EARLY MON. 500MB VORT WILL BE DIGGING
INTO THE UPPER MIDWEST EARLY MON. THE COMBINATION OF COOLER AIR
ALOFT AND SOME THIN CLOUD COVER MON MORNING WILL ALLOW LAPSE RATES
TO STEEPEN AND ADD THE POTENTIAL FOR ISOLATED STORM MON. SFC TEMPS
MON WILL BE STARTING THE COOL DOWN WITH HIGHS GENERALLY IN THE
LOW/MID 70S.
CONFIDENCE...MEDIUM/HIGH.
TUESDAY THROUGH FRIDAY...
ENSEMBLES CONTINUE TO DEMONSTRATE HIGH CONFIDENCE WITH MINIMAL
SPREAD AMONGST MEMBERS FOR THE BULK OF THE EXTENDED FORECAST
PERIODS. POTENT 500MB VORT WILL ARRIVE OVER THE GREAT LAKES
TUE...AND PRODUCE AN UNSEASONABLY COOL DAY WITH HIGHS STRUGGLING TO
WARM BEYOND THE 60S AS THE 850MB THERMAL TROUGH IS PROGGED AT 4 TO 6
DEG C. FORTUNATELY WITH BROAD SFC RIDGING ARRIVING TUE NGT AND
EXPECTED TO PERSIST THRU THE END OF THE WEEK...TEMPS WILL STEADILY
WARM INTO THE 70S.
CONFIDENCE...HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* MVFR CIGS DEVELOPING AROUND DAYBREAK AND PERSISTING THROUGH THE
MORNING
* CHANCE FOR TSRA LATE TONIGHT THROUGH MID AFTERNOON
SATURDAY...WITH GREATER CHANCES LATE SATURDAY AFTERNOON INTO
NIGHT. SOME STORMS COULD BE STRONG WITH GUSTY WINDS...WITH HEAVY
RAIN LIKELY.
KMD
//DISCUSSION...UPDATED 09Z...
AFTER A SLOW PROGRESSION...CEILINGS ARE BEGINNING TO LOWER EAST OF
THE MISSISSIPPI RIVER EARLY THIS MORNING...THOUGH IT HAS LARGELY
OCCASIONAL BROKEN CEILINGS AT 3500-4000 FEET. HAVE BACKED OFF ON THE
MVFR ARRIVAL BUT STILL FEEL THAT IN THE ISENTROPIC LIFT REGIME
AHEAD OF THE WARM FRONT IN NORTHERN AND EASTERN MISSOURI THAT
THERE WILL STILL BE SOME LOWER CEILINGS THIS MORNING. FORECAST
CONFIDENCE IS DECREASING SOMEWHAT ON THE EXTENT OF THE MVFR CIGS...BUT
MOS GUIDANCE THE HRRR AND NARRE STILL SUGGESTING A PERIOD FROM
12-16Z OF POTENTIAL LOWER CEILINGS...THE RAP SAYING IT MAY ONLY BE
BRIEF. WILL HANG ONTO THE LOWER CEILINGS BUT NOT START THEM UNTIL
12Z.. SHOWER ACTIVITY IS AT A MINIMUM WITH NO OBVIOUS UPPER LEVEL
FORCING AT THIS TIME...BUT STILL EXPECT AT LEAST SOME SCATTERED
SHOWER ACTIVITY EXPECTED TO CONTINUE THIS MORNING. CONFIDENCE
STILL TOO LOW ON ANY TAF FOR ISOLATED THUNDER AS THUNDER HAS BEEN
LARGELY FROM KPNT SOUTHWARD...BUT IT CANNOT BE RULED OUT.
INSTABILITY WILL BE ON THE INCREASE THROUGH THE DAY TODAY. STILL
HAVE SOME QUESTIONS ABOUT CONVECTIVE ACTIVITY DURING THE
AFTERNOON...BUT THE MOST ORGANIZED COUPLED FORCING FROM UPPER
LEVELS AND MOISTURE CONVERGENCE AHEAD OF THE APPROACHING COLD
FRONT. HEAVY RAIN AND GUSTY WINDS REMAIN THE BIGGEST
CONCERNS...AND IT COULD BE A LONGER PERIOD THUNDERSTORM ACTIVITY
AS THE FRONT IS NOT MOVING ALL THAT QUICKLY.
KMD
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* LOW-MEDIUM IN CEILINGS DOWN TO 2000 FT DEVELOPING TOWARDS
DAYBREAK LOW IN TIMING OF SCATTERING THIS MORNING...
* MEDIUM IN NO TSRA THROUGH EARLY SATURDAY AFTERNOON. LOW IN
WHETHER TSRA WILL HOLD OFF THE REMAINDER OF THE AFTERNOON.
* MEDIUM IN TSRA OCCURRING SATURDAY EVE.
KMD
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY-MONDAY...LOW CHANCES OF TSRA.
TUESDAY...SLIGHT CHANCE OF SHRA.
WEDNESDAY-THURSDAY...VFR LIKELY.
MTF
&&
.MARINE...
244 AM CDT
STILL SEEING GUSTS TO NEAR 20 KT ON THE NORTHERN HALF OF THE
LAKE...BUT DO EXPECT THE PRESSURE GRADIENT TO RELAX TONIGHT INTO
SATURDAY AS HIGH PRESSURE ALONG THE ATLANTIC COAST CONTINUES EAST.
A TROUGH OF LOW PRESS SURE AND FRONTAL BOUNDARY WILL CROSS THE LAKE
ON SATURDAY NIGHT. CONFIDENCE IS LOWER WITH REGARDS TO OVERALL
WIND DIRECTION AND SPEEDS SATURDAY EVENING INTO SATURDAY NIGHT AS
PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED ALONG THIS
FRONTAL BOUNDARY. A SERIES OF WEAK LOW PRESSURE SYSTEMS AND
ASSOCIATED COLD FRONTS WILL THEN PASS THROUGH THE LAKE THROUGH
MONDAY WHILE HIGH PRESSURE BUILDS INTO THE NORTHERN CENTRAL
PLAINS. WINDS SHIFT TO WEST- NORTHWEST BEHIND THE STRONGER COLD
FRONTAL PUSH MONDAY NIGHT AND REACH 20 KT OR POSSIBLY HIGHER
TUESDAY.
KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS MARQUETTE MI
329 AM EDT SAT JUL 12 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 429 PM EDT FRI JUL 11 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A ZONAL PATTERN THROUGH THE
NRN CONUS BETWEEN A TROUGH OVER CNTRL CANADA AND A RIDGE OVER THE
SRN PLAINS. A WEAK SHORTWAVE TROUGH OVER LAKE SUPERIOR INTO CNTRL
UPPER MI HELPED PRODUCE SOME LIGHT SHOWERS ACROSS THE CWA TODAY.
SCT/ISOLD SHRA/TSRA FROM NEAR KINL INTO N CNTRL MN HAD DEVELOPED
ALONG A COLD FRONT/TROUGH AHEAD OF ANOTHER WEAK SHRTWV MOVING
THROUGH NORTH DAKOTA. MOSTLY CLOUDY SKIES OVER UPPER MI HAD LIMITED
TEMPS TO THE LOWER TO MID 70S AND LIMITED MLCAPE VALUES TO LESS THAN
400 J/KG.
TONIGHT...EXPECT THAT SHRA/TSRA OVER NRN MN WILL EXPAND IN COVERAGE
AND MOVE TOWARD UPPER MI. HOWEVER...WITH ONLY MARGINAL INSTABILITY
FCST OVER THE AREA...MUCAPE INTO THE 400-800 J/KG RANGE...THE
CONVECTION SHOULD WEAKEN WITH ONLY ISOLD TSRA. SCT SHRA COVERAGE
WITH CHANCE POPS WAS MENTIONED GIVEN THE WEAK FORCING ASSOCIATED
WITH THE FRONT AND SHRTWV SLIDING THROUGH THE NRN GREAT LAKES. THE
REMAINING SHOWERS ARE EXPECTED TO MOVE INTO THE ERN CWA LATE THIS
EVENING AND DIMINISH FROM WEST TO EAST OVERNIGHT.
SATURDAY...THE WEAKENING COLD FRONT THROUGH UPPER MI WILL PROVIDE A
BOUNDARY/FOCUS FOR POTENTIAL SHRA/TSRA DEVELOPMENT...ESPECIALLY WITH
ONSET OF STRONGER DAYTIME HEATING. EXPECT THE GREATEST PCPN COVERAGE
OVER THE SOUTH AND THROUGH ERN UPPER MI WHERE THE HIGHER RES MODELS
SUGGEST THE LOW LEVEL CONV WILL BE STRONGEST. MLCAPE VALUES TO NEAR
1K J/KG...PER GEM-REGIONAL AND GFS COMBINED WITH 0-6KM SHEAR VALUES
OF 35-40 KNOTS COULD SUPPORT SOME STRONG AND POSSIBLY SEVERE STORMS
IF CLOUD DEPENDENT INSTABILITY IS REALIZED. THE MODELS HAVE ALSO SHOWN A
CONSISTENT SIGNAL THAT SHRA/TSRA WILL MOVE INTO WI ASSOCIATED WITH
STRONGER SHORTWAVE TROUGH. THERE IS STILL TIMING/POSITION UNCERTAINTY
ON HOW IT WOULD AFFECT MAINLY SRN UPPER MI BY LATE AFTERNOON.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 328 AM EDT SAT JUL 12 2014
NAM SHOWS A CLOSED 500 MB LOW OVER SOUTH CENTRAL CANADA 12Z SUN WITH
A 500 MB TROUGH DIGGING INTO THE GREAT LAKES REGION. UPPER AIR
PATTERN AMPLIFIES OVER THE AREA 12Z MON WITH THE LOW MOVING OVER THE
AREA ON MON. AS THE LOW MOVES OVER THE AREA ON MON...EXPECT SOME
INSTABILITY SHOWERS TO BREAK OUT WITH THE HIGHEST POPS DURING THE
PEAK DIURNAL HEATING. NAM SHOWS SOME DEEPER MOISTURE AND 850-500 MB
Q-VECTOR CONVERGENCE MOVING THROUGH THE AREA ON MON INTO MON NIGHT.
WILL HAVE SOME SMALL CHANCE POPS IN FOR THE ERN CWA SUN MORNING AND
THEN GO DRY FOR SUN AFTERNOON AND SUNDAY EVENING. WITH APPROACH OF
THE UPPER LEVEL LOW ON MON...WILL HAVE POPS INCREASING TO LIKELY IN
A FEW PLACES MON WITH PEAK DIURNAL HEATING HAVING THE HIGHEST POPS
IN THE AFTERNOON. WITH LOSS OF DIURNAL HEATING MON NIGHT...HAVE POPS
DECREASING BACK TO CHANCE TO SLIGHT CHANCES. OVERALL...DID NOT MAKE
TOO MANY CHANGES TO THE GOING FORECAST. TEMPERATURES WILL BEGIN THE
COOLING TREND THIS FORECAST PERIOD AND LOWERED HIGHS A BIT FOR SUN
THROUGH MON NIGHT.
IN THE EXTENDED...GFS AND ECMWF SHOW A DEEP 500 MB TROUGH AND CLOSED
LOW OVER THE ERN HALF OF NORTH AMERICA WITH VERY COLD TEMPERATURES
OVER THE AREA 12Z TUE. THE TROUGH REMAINS NEARLY STATIONARY INTO THU
BEFORE PATTERN MODIFICATION TAKES PLACE WITH THE TROUGH AND
AMPLIFICATION BREAKING DOWN. A RIDGE MOVES INTO THE ROCKIES 12Z FRI.
WHAT THIS WILL MEAN IS THE COOL CONDITIONS WILL CONTINUE FOR MOST OF
THE FORECAST PERIOD WITH A SLOW MODERATION IN TEMPERATURES. SFC
HIGH PRESSURE REMAINS IN CONTROL OF THE WEATHER AND LOOKS COOL AND
DRY FOR THE MOST PART. WILL KEEP SOME SMALL POPS IN FOR TUE WITH
DEPARTING UPPER LOW IN THE AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 140 AM EDT SAT JUL 12 2014
VFR CONDITIONS...WITH MAINLY HIGHER MVFR CONDITIONS AT KCMX...PREVAIL
OVERNIGHT. AS WINDS SHIFT AROUND TO A W TO NW DIRECTION BEHIND COLD
FROPA THIS MORNING...THE UPSLOPE WINDS AT KIWD/KCMX MAY RESULT IN A
PERIOD OF IFR CONDITIONS AND POTENTIALLY LIFR. MVFR CONDITIONS MAY
DEVELOP AT KSAW. ALL TERMINALS SHOULD RETURN TO VFR LATE MORNING INTO
THE AFTN. THERE MAY BE SHRA/TSRA AROUND KSAW THIS AFTN...BUT
LOCATION/COVERAGE OF ANY SHRA/TSRA DEVELOPMENT IS TOO UNCERTAIN AT
THIS POINT TO INCLUDE A MENTION IN FCST.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 429 PM EDT FRI JUL 11 2014
SOUTH WINDS OF UP TO 20 KTS...POSSIBLY 25 KTS AT HIGHER PLATFORMS
ABOVE MARINE LAYER...EXPECTED INTO THIS EVENING WILL DIMINISH
OVERNIGHT WITH WINDS SHIFTING TO SW. AS SCT SHOWERS ASSOCIATED WITH A
WEAK COLD FRONT OR TROUGH MOVE THROUGH LAKE SUPERIOR...FOG WILL BE
POSSIBLE ACROSS THE ENTIRE LAKE WITH THE TROUGH PASSAGE. LIGHT WINDS
WILL CONTINUE THROUGH SUNDAY BEFORE ANOTHER TROUGH PASSES
SOUTHEASTWARD ACROSS LAKE SUPERIOR SUNDAY NIGHT. GUSTY NORTHWEST
WINDS TO 20 KNOTS EXPECTED BEHIND THIS TROUGH EARLY NEXT WEEK AS HIGH
PRESSURE BUILDS OVER THE NORTHERN PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...07
AVIATION...ROLFSON
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
141 AM EDT SAT JUL 12 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 429 PM EDT FRI JUL 11 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A ZONAL PATTERN THROUGH THE
NRN CONUS BETWEEN A TROUGH OVER CNTRL CANADA AND A RIDGE OVER THE
SRN PLAINS. A WEAK SHORTWAVE TROUGH OVER LAKE SUPERIOR INTO CNTRL
UPPER MI HELPED PRODUCE SOME LIGHT SHOWERS ACROSS THE CWA TODAY.
SCT/ISOLD SHRA/TSRA FROM NEAR KINL INTO N CNTRL MN HAD DEVELOPED
ALONG A COLD FRONT/TROUGH AHEAD OF ANOTHER WEAK SHRTWV MOVING
THROUGH NORTH DAKOTA. MOSTLY CLOUDY SKIES OVER UPPER MI HAD LIMITED
TEMPS TO THE LOWER TO MID 70S AND LIMITED MLCAPE VALUES TO LESS THAN
400 J/KG.
TONIGHT...EXPECT THAT SHRA/TSRA OVER NRN MN WILL EXPAND IN COVERAGE
AND MOVE TOWARD UPPER MI. HOWEVER...WITH ONLY MARGINAL INSTABILITY
FCST OVER THE AREA...MUCAPE INTO THE 400-800 J/KG RANGE...THE
CONVECTION SHOULD WEAKEN WITH ONLY ISOLD TSRA. SCT SHRA COVERAGE
WITH CHANCE POPS WAS MENTIONED GIVEN THE WEAK FORCING ASSOCIATED
WITH THE FRONT AND SHRTWV SLIDING THROUGH THE NRN GREAT LAKES. THE
REMAINING SHOWERS ARE EXPECTED TO MOVE INTO THE ERN CWA LATE THIS
EVENING AND DIMINISH FROM WEST TO EAST OVERNIGHT.
SATURDAY...THE WEAKENING COLD FRONT THROUGH UPPER MI WILL PROVIDE A
BOUNDARY/FOCUS FOR POTENTIAL SHRA/TSRA DEVELOPMENT...ESPECIALLY WITH
ONSET OF STRONGER DAYTIME HEATING. EXPECT THE GREATEST PCPN COVERAGE
OVER THE SOUTH AND THROUGH ERN UPPER MI WHERE THE HIGHER RES MODELS
SUGGEST THE LOW LEVEL CONV WILL BE STRONGEST. MLCAPE VALUES TO NEAR
1K J/KG...PER GEM-REGIONAL AND GFS COMBINED WITH 0-6KM SHEAR VALUES
OF 35-40 KNOTS COULD SUPPORT SOME STRONG AND POSSIBLY SEVERE STORMS
IF CLOUD DEPENDENT INSTABILITY IS REALIZED. THE MODELS HAVE ALSO SHOWN A
CONSISTENT SIGNAL THAT SHRA/TSRA WILL MOVE INTO WI ASSOCIATED WITH
STRONGER SHORTWAVE TROUGH. THERE IS STILL TIMING/POSITION UNCERTAINTY
ON HOW IT WOULD AFFECT MAINLY SRN UPPER MI BY LATE AFTERNOON.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 431 PM EDT FRI JUL 11 2014
THE MAIN STORY IN THE LONG TERM CONTINUES TO BE THE SEPTEMBER-LIKE
CONDITIONS EXPECTED ACROSS THE UPPER GREAT LAKES EARLY NEXT WEEK.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...A DEEP MID-LEVEL LOW OVER FAR
SOUTHWEST HUDSON BAY WILL CONTINUE ITS TREK SOUTHWARD AT THE
BEGINNING OF THE PERIOD. CONVECTIVE POTENTIAL ACROSS THE SOUTHEAST
HALF FOR SATURDAY NIGHT WILL DEPEND HEAVILY ON BOTH THE AMOUNT OF
DIURNAL HEATING SATURDAY AND THE LOCATION OF THE DECAYING LOW-LEVEL
CONVERGENCE ZONE. WHILE MCS ACTIVITY LOOKS TO BE MOST PRONOUNCED
ALONG THE NOSE OF A DEVELOPING LOW-LEVEL JET ACROSS WI SATURDAY
AFTERNOON AND EVENING...RESIDUAL 305-315K ISENTROPIC LIFT NORTH OF
THE LOW-LEVEL BOUNDARY MAY BE ENOUGH TO TAP INTO REMAINING MUCAPE OF
AROUND 500 J/KG AS NOTED BY BOTH THE 12Z NAM AND 12Z GEM. ANY
THUNDER ACTIVITY SHOULD REMAIN WEAK THIS FAR NORTH GIVEN A STABLE
SFC LAYER AND OVERALL LIMITED INSTABILITY. HOWEVER...A FEW STRONGER
GUSTS CANNOT BE RULED OUT IN THE EARLY EVENING HOURS FAR SOUTH
CENTRAL WITH ANY STORM ROOTED ALONG THE SFC CONVERGENCE ZONE.
A MID-LEVEL TROUGH AXIS ASSOCIATED WITH THE DEEP LOW WILL CROSS THE
CWA FROM WEST TO EAST LATE SATURDAY NIGHT INTO SUNDAY. WITH LITTLE
ADDITIONAL SUPPORT AND GENERALLY DRY CONDITIONS...ONLY SOME ISOLATED
SHOWER ACTIVITY IS EXPECTED. AFTER THE TROUGH PASSAGE ON
SUNDAY...SKIES LOOK TO BECOME MOSTLY CLEAR FOR A 12-18 HOUR WINDOW.
THIS WILL ALLOW FOR INCREASED MIXING ACROSS THE WEST...WITH WESTERLY
GUSTS TO 25 MPH ACROSS THE KEWEENAW.
MONDAY AND TUESDAY...BY MONDAY MORNING...THE MID-LEVEL LOW WILL
SPLIT INTO TWO WAVES OVER ONTARIO. THE EASTERN SEGMENT OVER
SOUTHERN JAMES BAY WILL EJECT NORTHEASTWARD ACROSS QUEBEC THROUGH
MONDAY. MEANWHILE...THE WESTERN SEGMENT WILL BE TRACKING
SOUTHEASTWARD ACROSS THE BOUNDARY WATERS OF MN AROUND 12Z MONDAY.
THIS WESTERN EXTENSION WILL BECOME STACKED UPWARD FROM H7...SO
PROGRESSION OF THE SYSTEM WILL BE QUITE SLOW. THE MID/UPPER-LOW IS
PROGGED TO TRACK FROM NEAR DLH MONDAY AFTERNOON TO NEAR GRB BY
TUESDAY AFTERNOON. GIVEN THE OVERALL DYNAMICS OF THE SYSTEM...THE
ENTIRE AREA SHOULD SEE AT LEAST SOME SHOWERS DURING THE DAY. ONE
LIMITING FACTOR TO COVERAGE IS A PRESENCE OF DEEP MOISTURE. SOMEWHAT
DRY AIR ABOVE H5 SHOULD KEEP SHOWERS LESS WIDESPREAD AWAY FROM THE
LOW CENTER. SOME DIURNAL HEATING ASSISTANCE WILL ALSO ALLOW FOR
GREATER COVERAGE AWAY FROM THE GREAT LAKES. THEREFORE...THE BEST
COVERAGE IS EXPECTED ALONG THE WI BORDER...WHERE LIKELY POPS HAVE
BEEN INTRODUCED.
TEMPS WILL BE QUITE COOL FOR MID-JULY...WITH H8 TEMPS AT OR BELOW
5C. WITH CLOUDY AND SHOWERS AROUND...HIGHS WILL STRUGGLE TO GET OUT
OF THE 50S ACROSS MUCH OF THE CWA BOTH MONDAY AND TUESDAY. SOME
LOCALES ALONG LAKE SUPERIOR MAY EVEN FAIL TO REACH 50. THESE NUMBERS
ARE 25 DEGREES BELOW AVERAGE...AND WILL LIKELY SET RECORD LOW
MAXIMUM TEMPS ACROSS THE AREA.
SHOWERY ACTIVITY WILL CONTINUE INTO TUESDAY WITH THE PASSAGE OF A
DEFORMATION/FGEN REGION ON THE BACKSIDE OF THE MID/UPPER LOW. THESE
SHOWERS WILL BE SLOW TO MOVE EASTWARD AS THE LOW ONLY REACHES
NORTHERN LAKE HURON BY LATE TUESDAY NIGHT.
WEDNESDAY THROUGH FRIDAY...THE GFS ADVERTISES A MUCH QUICKER
DEPARTURE OF THE MID-LEVEL LOW THAN THE ECMWF/GEM. THIS HAS
IMPLICATIONS ON THE AMOUNT OF MOISTURE AVAILABLE FOR CONTINUED CLOUD
COVER AND HIGH TEMPS ACROSS THE AREA. OTHERWISE...THE STOUT RIDGE
ACROSS THE WESTERN STATES AND PROVINCES THAT DEVELOPED IN RESPONSE
TO THE DEEP EASTERN TROUGH WILL BEGIN TO SHIFT ACROSS THE NORTHERN
PLAINS ON THURSDAY AND THE UPPER GREAT LAKES ON FRIDAY. THIS SHOULD
BRING AN OVERALL QUIET PERIOD OF WEATHER WITH A GRADUAL WARMING
TREND INTO THE WEEKEND. TEMPS LOOK TO BE BACK TO JUST BELOW AVERAGE
BY FRIDAY. HOWEVER...A FEW DIURNAL INLAND SHOWERS COULD BE POSSIBLE
WITH RETURN MOISTURE THURSDAY AFTERNOON.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 140 AM EDT SAT JUL 12 2014
VFR CONDITIONS...WITH MAINLY HIGHER MVFR CONDITIONS AT KCMX...PREVAIL
OVERNIGHT. AS WINDS SHIFT AROUND TO A W TO NW DIRECTION BEHIND COLD
FROPA THIS MORNING...THE UPSLOPE WINDS AT KIWD/KCMX MAY RESULT IN A
PERIOD OF IFR CONDITIONS AND POTENTIALLY LIFR. MVFR CONDITIONS MAY
DEVELOP AT KSAW. ALL TERMINALS SHOULD RETURN TO VFR LATE MORNING INTO
THE AFTN. THERE MAY BE SHRA/TSRA AROUND KSAW THIS AFTN...BUT
LOCATION/COVERAGE OF ANY SHRA/TSRA DEVELOPMENT IS TOO UNCERTAIN AT
THIS POINT TO INCLUDE A MENTION IN FCST. &&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 429 PM EDT FRI JUL 11 2014
SOUTH WINDS OF UP TO 20 KTS...POSSIBLY 25 KTS AT HIGHER PLATFORMS
ABOVE MARINE LAYER...EXPECTED INTO THIS EVENING WILL DIMINISH
OVERNIGHT WITH WINDS SHIFTING TO SW. AS SCT SHOWERS ASSOCIATED WITH A
WEAK COLD FRONT OR TROUGH MOVE THROUGH LAKE SUPERIOR...FOG WILL BE
POSSIBLE ACROSS THE ENTIRE LAKE WITH THE TROUGH PASSAGE. LIGHT WINDS
WILL CONTINUE THROUGH SUNDAY BEFORE ANOTHER TROUGH PASSES
SOUTHEASTWARD ACROSS LAKE SUPERIOR SUNDAY NIGHT. GUSTY NORTHWEST
WINDS TO 20 KNOTS EXPECTED BEHIND THIS TROUGH EARLY NEXT WEEK AS HIGH
PRESSURE BUILDS OVER THE NORTHERN PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KLUBER
AVIATION...ROLFSON
MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1103 PM CDT FRI JUL 11 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 241 PM CDT FRI JUL 11 2014
LATEST VISIBLE IMAGERY SHOWS AN AREA OF EXTENSIVE LOW CLOUDS NEAR
AND DOWNWIND OF THE SURFACE FRONT/TROUGH AXIS WITH A MORE HEALTHY CU
FIELD TRYING TO DEVELOP NEAR ITS BACK EDGE AND POINTS UPSTREAM.
CLOUDS HAVE MANAGED TO BREAK UP SOUTHEAST OF THERE... INCLUDING THE
SOUTHERN AND EASTERN PORTION OF THE TWIN CITIES... IN THE WAKE OF
THIS MORNING/S CONVECTION. INSTABILITY HAS INCREASE ACROSS THE
WESTERN CWFA... WITH MLCAPE VALUES AOA 500 J/KG WITH NEAR 1500 J/KG
OVER THE FAR WEST. A SUBTLE SHORTWAVE FEATURE CAN BE SEEN IN THE
WATER VAPOR IMAGERY MOVING EAST THROUGH THE ZONAL FLOW ACROSS NORTH
DAKOTA AT THE CURRENT TIME. THIS COULD WORK WITH THE WEAK
CONVERGENCE PRESENT NEAR THE SURFACE TROUGH TO GENERATE SOME
ISOLATED/SCATTERED SHRA/TSRA LATE THIS AFTERNOON INTO EARLY THIS
EVENING. THE NAM IS NOT PARTICULARLY OPTIMISTIC ABOUT ANYTHING OVER
OUR AREA... WHILE THE GFS AND ECMWF MANAGE TO SHOW SOME LIGHT PCPN.
THE CAMS ARE A MIXED BAG... WITH MANY SUCH AS THE HRRR AND A COUPLE
HOPWRF MEMBERS KEEPING THINGS GENERALLY DRY... WHILE A COUPLE HOPWRF
MEMBERS AND THE HIRES WINDOW RUNS MANAGE TO SHOW A FEW CONVECTIVE
CELLS. ALLOWED FOR CHANCE POPS OVER THE AREA FROM LATE AFTERNOON
INTO EVENING TO ACCOUNT FOR THE POSSIBILITY OF A FEW SHRA/TSRA
GETTING GOING. OTHERWISE... THE MAIN LARGE SCALE SUPPORT FOR PCPN
THROUGH TOMORROW LOOKS TO SHIFT TO THE SOUTHERN PORTION OF THE AREA
AND EVEN MORE SO PERHAPS INTO IOWA WHERE THE BAROCLINIC ZONE LOOKS
TO STALL OUT AND THE BEST FRONTOGENESIS AND THETA-E ADVECTION IS
EXPECTED. ALLOWED FOR SOME OF THIS TO SPREAD NORTH DURING THE DAY ON
SATURDAY AS THE FLOW STARTS TO AMPLIFY AND WE SEE A SOMEWHAT
HEALTHIER SHORTWAVE ARRIVE FROM THE WEST.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 241 PM CDT FRI JUL 11 2014
THE LONG TERM PORTION OF THE FORECAST WILL BE GREATLY INFLUENCED BY
A HIGHLY AMPLIFIED LARGE SCALE PATTERN...WITH A DEEP TROUGH
DOMINATING EASTERN CANADA/CONUS...AND RIDGING PREVAILING OVER THE
WEST. SAID PATTERN WILL TRANSLATE TO BELOW NORMAL TEMPERATURES FOR
THE EASTERN TWO-THIRDS OF THE CONUS THROUGH MUCH OF NEXT WEEK.
SATURDAY EVENING SHOULD BRING THE EXIT OF ANY LINGERING SHOWERS
AND THUNDERSTORMS...WITH SKIES CLEARING OUT BY SUNDAY.
THUNDERSTORMS LOOK A BIT LESS LIKELY FOR SUNDAY PER THE 12Z MODEL
RUNS...WITH THE ONLY SLIM POTENTIAL APPEARING TO BE OVER FAR
SOUTHERN MN WHERE DIURNALLY-INDUCED ACTIVITY COULD DEVELOP IN THE
WANING BAROCLINIC ZONE.
MONDAY BRINGS THE ARRIVAL OF THE UPPER LOW OVERHEAD...MADE EVIDENT
BY SCATTERED SHOWERS AND TEMPERATURES NEARING 20 DEGREES BELOW
NORMAL. HIGHS IN THE LOW/MID 60S WILL COMBINE WITH BREEZY NORTHWEST
WINDS TO MAKE FOR A CHILLY DAY.
TUESDAY THE TROUGH CENTER WILL HAVE SHIFTED EAST OF THE AREA...SO
SHOWER CHANCES WILL BE MAINLY CONFINED TO WEST CENTRAL WI
COUNTIES. HIGHS WILL MODERATE A TAD...BUT WILL LIKELY STILL TOP
OUT IN THE MID/UPPER 60S.
WEDNESDAY AND THURSDAY THE LOW LIFTS INTO QUEBEC AND HEIGHTS RISE
A BIT. THIS WILL MEAN GRADUALLY MODERATING TEMPERATURES AND DRY
WEATHER...WITH HIGHS IN THE LOW/MID 70S ON WEDNESDAY...AND
MID/UPPER 70S FOR THURSDAY.
BY FRIDAY THE FLOW TRANSITIONS TO NEARLY ZONAL ACROSS THE
CONUS...AS WEAK MID LEVEL TROUGHING OVER SOUTHERN
SASKATCHEWAN/MANITOBA INDUCES HIGH PLAINS SURFACE CYCLOGENESIS.
SOUTHERLY FLOW AHEAD OF THIS FEATURE WILL AID IN FURTHER TEMPERATURE
MODERATION ON FRIDAY...WITH HIGHS IN THE UPPER 70S AND LOWER 80S.
STILL LOOKS TO BE DRY ON FRIDAY...ALTHOUGH THE AFOREMENTIONED
TROUGH SHOULD FACILITATE SHOWER AND THUNDERSTORM CHANCES AT SOME
POINT NEXT WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1103 PM CDT FRI JUL 11 2014
LOW CONFIDENCE FORECAST OVERNIGHT WITH RESPECT TO THE IFR
CEILING/VSBY POTENTIAL AT KRNH AND KEAU. THE COLD FRONT NEAR AN KAXN
TO KHON LINE HAS HARDLY MOVED THIS EVENING IN RESPONSE TO A WAVE
OF LOW PRESSURE DEVELOPING ON THE TAIL END OF THE FRONT. A FEW
TSRA CONTINUE TO MOVE SE OF KJMR. THESE SHOULD DISSIPATE WHILE
PASSING JUST NE OF KRNH. WITH THE FRONT NEARLY STALLING...THIS HAS
KEPT LOW VFR CLOUDINESS FROM SE MN THROUGH WEST CENTRAL WI FROM
BEING PUSHED EAST. THERE IS STILL A WINDOW OF OPPORTUNITY LATE IN
THE NIGHT FOR THIS CLOUDINESS TO BREAK UP SOME...ALLOWING FOG AND
STRATUS CEILINGS TO FORM. HOWEVER...MORE MID/HIGH LEVEL CLOUDS ARE
ALREADY FILTERING INTO WESTERN MN FROM CONVECTION IN THE WESTERN
HIGH PLAINS. THEREFORE...MODIFIED MAINLY THE LOW VISIBILITY
FORECAST AT KRNH AND KEAU DUE TO MORE HIGHER LEVEL CLOUDINESS BUT
HELD ON TO THE LOW CEILING FORECAST. KMSP...KSTC AND KRWF ARE BETTER
SUITED FOR MVFR FOG ALMOST RIGHT OUT THE GATE...BUT AGAIN...THE
INCREASING MID/HIGH LEVEL CLOUDS SHOULD TEMPER ON HOW LOW VSBYS
GO. HELD ON TO MVFR CIGS FOR A TIME SATURDAY MORNING AT KRNH AND
KEAU AS THE WAVE OF LOW PRESSURE RIDES NORTHEAST ALONG THE FRONT.
SHOWERS AND ISOLATED THUNDERSTORM WILL SPREAD INTO WEST CENTRAL
AND SOUTHERN MN BEFORE DAYBREAK SATURDAY AND PERSIST THROUGH MUCH
OF THE DAY. KRWF SHOULD SEE SCATTERED SHOWERS BUT MVFR CONDITIONS
ARE FORECAST TO REMAIN SOUTH OF THIS SITE. LIGHT WINDS OVERNIGHT
TONIGHT WITH NORTHWEST TO WEST WINDS LESS THAN 10 KNOTS ON
SATURDAY.
KMSP...CONFIDENCE LOW ON THE CEILING/VSBY FORECAST OVERNIGHT.
CERTAINLY SEEMS TO BE HIGH POTENTIAL FOR LOW CONDITIONS DEVELOPING
WITH A VERY MOIST LOW LEVEL PROFILE IN PLACE. THE QUESTION IS
WHETHER THE INCREASING MID/HIGH LEVEL CLOUDS FROM THE WEST
OVERRULE AND KEEP THINGS VFR. IN KEEPING WITH THE LOW CEILINGS...HELD
ON TO MVFR CEILINGS INTO MID MORNING AS THE COLD FRONT MOVES
THROUGH. A RATHER ORGANIZED AREA OF SHOWERS WILL BE JUST SOUTH OF
THE AIRFIELD BY MIDDAY SATURDAY AND PERSIST THROUGH THE AFTERNOON.
VCSH USED AT THIS POINT.
/OUTLOOK FOR KMSP/
SATURDAY NIGHT...VFR. WEST WINDS LESS THAN 10 KTS BECOMING NORTHWEST.
SUNDAY...VFR. NORTHWEST WINDS 10 TO 15 KTS.
SUNDAY NIGHT. MVFR POSSIBLE WITH A CHANCE OF SHRA/TSRA. NORTHWEST
WINDS 5 TO 10 KTS.
MONDAY...MVFR POSSIBLE WITH A CHANCE OF SHRA/TSRA. NORTHWEST
WINDS 15 TO 25 KTS.
MONDAY NIGHT...MVFR POSSIBLE. NORTHWEST WINDS 10 TO 15 KTS.
TUESDAY...VFR. NORTHWEST WINDS 10 TO 15 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...TRH
LONG TERM...LS
AVIATION...RAH
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
351 AM CDT Sat Jul 12 2014
.DISCUSSION...
Issued at 351 AM CDT SAT JUL 12 2014
Overnight convection remains mostly located in areas from northeast
Nebraska arching through central Iowa into Illinois, which coincides
with edge of the nocturnal jet where warm air and moisture transport
is piling up early this morning. Closer to home, starting to get
some scattered radar returns across central Missouri likely owing to
weak moisture transport noted from the SPCs meso-analysis page.
Early morning showers in central Missouri don`t look like they will
last long. HRRR and other meso-models advertising this modest
activity all have it dissipating as quickly as it appeared as the
primary focus for moisture transport will remain to our north along
the southern edge of the prevailing westerlies across Nebraska and
Iowa today. Convection to our north will likely reinforce a weak
cold front settling south into Kansas and Missouri late tonight,
which will eventually bring the focus for some rain farther south
--likely after midnight--. However, before that occurs we will have
to get through a hot and muggy day. H8 temperatures today in the 20C
to 22C range, along with plenty of insolation thanks to clearing
skies, should allow temperates to reach into the 90s across the
entire forecast region today.
For tonight...have bumped POPs after midnight into the likely range
as models are consistent in settling the activity across Nebraska
and Iowa into at least northern Missouri as the front settles south.
Rainfall totals across far northern Missouri could be a bit high
owing to precipitable water values will be over 1.5 inches, though
the storms should be progressive enough with the fronts movement to
limit flooding issues. Otherwise, severe potential can not be ruled
out, but shear looks highly confined to the front and late night
instability is not looking overly favorable. That said, small hail,
locally gusty winds and torrential rain would be the hazards to
highlight with any of our late Saturday Night/early Sunday Morning
activity.
Storm chances will linger into Sunday, but the next best chance for
storms looks to hold off till Monday as a shortwave trough rotates
through the northern Plains into the Great Lakes. This will push a
more substantial cold front into Missouri providing focus for more
storms.
Otherwise, still looking at the potential for record low maximum
temperatures for Tuesday and record low temperatures both Tuesday
and Wednesday as cool Canadian air settles south into the Plains
States.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday Night)
Issued at 1212 AM CDT SAT JUL 12 2014
Little change in this forecast from the previous forecast. Inserted
an ending time for the wind gusts Saturday evening. A cold front will
sag southward through the evening/overnight hours on Saturday night.
Expect the convective activity to remain north of the terminals until
the very end of the forecast period, but thunderstorms should be
moving into KSTJ and KMCI/KMKC shortly after 06z.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
DISCUSSION...Cutter
AVIATION...Leighton
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
355 AM CDT SAT JUL 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM CDT SAT JUL 12 2014
THE MODELS BRING ANOTHER DISTURBANCE THROUGH THE FCST AREA THIS
AFTERNOON. THERE ARE DIFFERENCES IN THE FOCUS FOR THUNDERSTORM
DEVELOPMENT. THE ECM FAVORS THE HIGH PLAINS AND SWRN NEB WHILE
THE NAM AND GEM SOLNS FAVOR NRN NEB. THE FORECAST FOLLOWS A BLEND
OF THESE SOLNS FOR ISOLATED TO SCATTERED POPS. NONE OF THE MODELS
SHOW HEAVY RAIN DEVELOPING BUT GIVEN THE WEAK FOCUS THIS MIGHT BE
NORMAL.
THE RAP SUGGESTS NO SIGNIFICANT DECREASE IN MOISTURE...PWS OVER
1.5 INCHES...SO STORMS WHICH FORM SHOULD CONTINUE TO PRODUCE
LOCALLY HEAVY RAINFALL.
LIGHT NORTH WINDS DEVELOP TODAY WITH LOW PRESSURE SOUTH OF THE
FCST AREA. THIS SHOULD LIMIT HIGHS TO THE 70S TO MID 80S. TONIGHT
LOWS FALL INTO THE 50S TO LOWER 60S AS THE FIRST PUSH OF DRIER
COOLER AIR MOVES INTO THE FCST AREA.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 354 AM CDT SAT JUL 12 2014
A COLD FRONT WILL PUSH INTO THE REGION LATE SUNDAY. AHEAD OF THE
FRONT PARTLY CLOUDY TO MOSTLY SUNNY SKIES SHOULD HELP TO WARM
TEMPS INTO THE 80S. ELEVATED INSTABILITY IS MARGINAL AND NOT
LOOKING AS GOOD AS YESTERDAY. PWATS DROP TO AROUND 1 INCH...WHICH
IS BELOW THE 50 PERCENTILE FOR JULY. EVEN THOUGH MOISTURE IS
LIMITED COOL AIR ALOFT WILL CREATE SOME STEEP LAPSE RATES. LOWERED
POPS FOR THE DAY...ALTHOUGH DID NOT ELIMINATE. MEANWHILE
UNSEASONABLY COLD UPPER LEVEL WILL BE DRIFTING ACROSS CENTRAL
CANADA TOWARDS THE GREAT LAKES.
THE COLD FRONT WILL MOVE ACROSS THE AREA SUNDAY NIGHT. SFC HIGH
PRESSURE WILL DEVELOP OVER THE DAKOTAS INTO NEB FOR MONDAY. BY
TUESDAY NIGHT INTO WEDNESDAY THE HIGH WILL DOMINATE MOST OF THE
PLAINS. TEMPS ASSOCIATED WITH THE HIGH WILL BE NOTICEABLY
COOLER...WITH HIGHS ONLY IN THE 70S...WITH MANY LOCATIONS HOLDING
IN THE LOWER 70S. MONSOON FLOW CONTINUES ALONG THE
SOUTHERN/CENTRAL ROCKIES. MODELS BRING SOME OF THIS MOISTURE INTO
SW NEB AND WILL CONTINUE LOW POPS.
COLD SNAP WILL BEGIN TO RELAX LATE WED AS THE UPPER LEVEL LOW WILL
LIFT INTO TO THE NORTHEAST. THE WESTERN RIDGE WILL THEN EXPAND
ACROSS THE ROCKIES. MODELS PUSH THE MONSOON MOISTURE SOUTH AS WARM
AIR EXPANDS ACROSS THE AREA. HIGHS SHOULD REBOUND BACK TO AROUND
80 FOR THURSDAY AND INTO THE 80S FOR FRIDAY. NUMERICAL MOS
GUIDANCE BRINGS TEMPS INTO THE 90S FOR FRIDAY ACROSS THE
WEST...HOWEVER THE WAY THIS SUMMER HAS GONE...HIGHS LIKELY IN THE
MID TO UPPER 80S. FLOW BECOMES NORTHWEST AND WILL HAVE TO MONITOR
DISTURBANCES FOR POSSIBLE ISOLATED ACTIVITY. FORECAST IS DRY AT
THIS TIME...BUT LOW POPS MAY BE NEEDED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1237 AM CDT SAT JUL 12 2014
THUNDERSTORMS AROUND THE AREA WILL CONTINUE BEYOND 08Z...BUT THE
PROBABILITY OF A THUNDERSTORM AT ANY ONE POINT IS LOW.
THEREFORE...AFTER 07Z...WE WILL KEEP THE MENTION TO VCTS BOTH VTN
AND LBF. RADAR INDICATIONS ARE THAT TWO ORGANIZED STORM SYSTEMS ARE
DEVELOPING AS THE RAPID UPDATE SHORT TERM FORECASTS INDICATED. THERE
IS STILL A POSSIBILITY THAT THE MOVEMENT OF THE THUNDERSTORMS COULD
CHANGE AND BRING STORMS TO LBF AND VTN BEFORE 09Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1238 AM CDT SAT JUL 12 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 326 PM CDT FRI JUL 11 2014
A WARM FRONT EXTENDING FROM NEAR IMPERIAL IN SOUTHWEST NEBRASKA TO
OMAHA IN EASTERN NEBRASKA...WILL REMAIN NEARLY STATIONARY THROUGH
TONIGHT. A SOUTHERLY LOW LEVEL JET WILL DEVELOP ACROSS WESTERN
KANSAS THIS EVENING. THE NOSE OF THE JET WILL BE DIRECTED AT
SOUTHWEST NEBRASKA THROUGH THE EVENING HOURS...AND THEN VEER
SOUTHWEST TOWARD SOUTH CENTRAL NEBRASKA AFTER MIDNIGHT.
A COUPLE OF DIFFERENT SCENARIOS ARE POSSIBLE REGARDING CONVECTIVE
CHANCES LATE THIS AFTERNOON AND EVENING. FIRST...THUNDERSTORMS
CURRENTLY DEVELOPING NEAR THE LARAMIE RANGE ACROSS SOUTHEAST WYOMING
/AIDED BY A FAIRLY SIGNIFICANT SHORTWAVE ALOFT MOVING EASTWARD
TOWARD THAT AREA/ SHOULD PROPAGATE EAST INTO WESTERN NEBRASKA THIS
EVENING. DEEP MOISTURE AND UNSTABLE CONDITIONS RESIDE ACROSS MUCH OF
NEBRASKA TO THE NORTH OF THE AFOREMENTIONED WARM FRONT. LOW LEVEL
EASTERLY SURFACE WINDS NORTH OF FRONT WILL AID STORM-RELATIVE
INFLOW...AND THE DEVELOPING SOUTHERLY LOW LEVEL JET SHOULD FURTHER
SUPPORT INFLOW AS WELL AS CONTINUED MOISTURE ADVECTION. DUE TO THE
SEEMINGLY FAVORABLE CONDITIONS...THESE STORMS WILL LIKELY FORM INTO
A CLUSTER AND POSSIBLY AN MCS AS THEY MOVE EAST TOWARD CENTRAL/NORTH
CENTRAL NEBRASKA MID EVENING ONWARD. THE SECOND AND LESS LIKELY
SCENARIO WOULD BE FOR A FEW SURFACE BASED STORMS TO DEVELOP ACROSS
FAR SOUTHWEST NEBRASKA NEAR THE WARM FRONT LATE THIS AFTERNOON AND
EVENING. THESE WOULD LIKELY BE HIGH BASED AND ISOLATED. THE LATEST
RUN OF THE HRRR MODEL SUPPORTS THE FIRST SCENARIO...AND THE FORECAST
WILL BE TAILORED IN THAT DIRECTION.
A SHORTWAVE DISTURBANCE WILL BE CROSSING THE AREA SATURDAY
MORNING...WITH AT LEAST SCATTERED ELEVATED SHOWERS AND THUNDERSTORMS
EXPECTED TO BE ONGOING THROUGH THE MORNING HOURS. A WEAK COLD FRONT
WILL DROP SOUTH THROUGH THE AREA SATURDAY AFTERNOON. THIS FRONT WILL
MERGE WITH THE WARM FRONT ACROSS SOUTHERN NEBRASKA OR NORTHERN
KANSAS...WHERE SURFACE BASED CONVECTION IS POSSIBLE LATE IN THE
AFTERNOON. ACROSS OUR AREA...MOIST EAST/NORTHEAST UPSLOPE LOW LEVEL
FLOW WILL CONTINUE...AND THUNDERSTORMS SHOULD DEVELOP EASTWARD OFF
THE HIGHER TERRAIN INTO WESTERN NEBRASKA LATE SATURDAY AFTERNOON AND
EVENING. ACTIVITY SHOULD REMAIN SCATTERED AS FORCING IS EXPECTED TO
BE WEAK AS SHORTWAVE PUSHES EAST OF THE AREA. WILL LIMIT POPS TO 30
PERCENT FOR MOST LOCATIONS DURING THE AFTERNOON.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 326 PM CDT FRI JUL 11 2014
THE MAIN POINTS OF THE LONG TERM FORECAST INCLUDE COOLER
TEMPERATURES AND A DECREASE IN CHANCES OF SHOWERS/THUNDERSTORMS. THE
PERIOD STARTS OFF WITH AN UPPER LEVEL DISTURBANCE PASSING THROUGH
THE NORTHERN PLAINS INTO THE GREAT LAKES REGION. A STATIONARY FRONT
WILL EXIST TO THE SOUTH IN KS SATURDAY NIGHT...WHILE A COLD FRONT
ASSOCIATED WITH THE DISTURBANCE PUSHES SOUTH ACROSS THE DAKOTAS. A
STRONGER UPPER LEVEL WAVE ROTATING AROUND THE MAIN UPPER LEVEL LOW
WILL MOVE SOUTHEAST ACROSS ND/MN/WI ON MONDAY. STRONG SURFACE HIGH
PRESSURE WILL FOLLOW THIS UPPER LOW AND HELP PUSH UNSEASONABLY COOL
TEMPERATURES INTO THE REGION ON MONDAY. THE HIGH WILL SETTLE IN OVER
THE AREA MONDAY NIGHT...MAKING FOR A COOL TUESDAY MORNING. WITH THE
HIGH SLOW TO MOVE EAST...HIGHS WILL BE IN THE 70S ON TUESDAY AND
WEDNESDAY. TEMPERATURES BEGIN TO REBOUND CLOSER TO NORMAL TOWARD THE
END OF THE WEEK UNDER UPPER LEVEL RIDGING.
STRONG THUNDERSTORMS WILL BE POSSIBLE SATURDAY NIGHT AND SUNDAY
NIGHT. MODERATE INSTABILITY AND DEEP SHEAR OF 30-40 KTS MAY LEAD TO
A FEW SEVERE STORMS SATURDAY NIGHT. INSTABILITY AND SHEAR BOTH LOOK
A LITTLE WEAKER FOR SUNDAY...LIMITING THE SEVERE RISK A BIT COMPARED
TO SATURDAY NIGHT. THERE IS ALSO MORE UNCERTAINTY REGARDING THE
LOCATION OF THE FRONT AND INSTABILITY ON SUNDAY. A FEW OTHER CHANCES
WILL EXIST ACROSS THE AREA EARLY IN THE WEEK...PRIMARILY IN THE SW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1237 AM CDT SAT JUL 12 2014
THUNDERSTORMS AROUND THE AREA WILL CONTINUE BEYOND 08Z...BUT THE
PROBABILITY OF A THUNDERSTORM AT ANY ONE POINT IS LOW.
THEREFORE...AFTER 07Z...WE WILL KEEP THE MENTION TO VCTS BOTH VTN
AND LBF. RADAR INDICATIONS ARE THAT TWO ORGANIZED STORM SYSTEMS ARE
DEVELOPING AS THE RAPID UPDATE SHORT TERM FORECASTS INDICATED. THERE
IS STILL A POSSIBILITY THAT THE MOVEMENT OF THE THUNDERSTORMS COULD
CHANGE AND BRING STORMS TO LBF AND VTN BEFORE 09Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...TAYLOR
LONG TERM...KNUTSVIG
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1132 PM MDT FRI JUL 11 2014
.AVIATION...
06Z TAF CYCLE
MAIN FOCUS FOR RAIN SHOWERS AND SOME EMBEDDED THUNDERSTORMS WILL
LIE BETWEEN THE WESTERN AND CENTRAL TERMINAL SITES REST OF
TONIGHT. USING VCSH AT FMN/GUP FOR A GOOD PORTION OF THE
OVERNIGHT. TOOK VCSH OUT OF ABQ/AEG AND SAF ALTHOUGH CANT RULE OUT
SOME SHORT DURATION EFFECTS THROUGH THE NEXT FEW HOURS. MTN TOP
OBCSD WILL OCCASIONALLY BE FOUND ALONG THE SAN MATEOS AND
CONTINENTAL DIVIDE AREA BUT CIGS SHOULD GENERALLY REMAIN ABOVE
MVFR CATEGORIES. THE ONE EXCEPTION WOULD BE FOUND ACROSS THE SE
PLAINS. GUIDANCE IS GOING A LITTLE MORE BULLISH FOR ROW SEEING
SOME MVFR IMPACTS. LOWERED CIGS THERE ACCORDINGLY. SOME SIGNATURE
AT TCC/LVS BUT LESS LIKELY SO KEPT MENTION OUT OF THOSE TERMINAL
SITES. ANOTHER ROUND OF SH/TS WILL IMPACT WESTERN AND CENTRAL
SITES SATURDAY AFTERNOON/EVENING. USING VCSH AS A PLACEHOLDER AT
THE PRESENT TIME.
50
&&
.PREV DISCUSSION...811 PM MDT FRI JUL 11 2014...
.UPDATE...
ALLOWED THE FLASH FLOOD WATCH TO EXPIRE AT 8 PM MDT. TWEAKED POPS
A BIT FOR THE EVENING AND OVERNIGHT PERIODS. MAINLY ADJUSTED FAR
EASTERN EDGE TO LOWER OR REMOVE POPS. ZONES OUT SHORTLY. CHJ
&&
.PREV DISCUSSION...328 PM MDT FRI JUL 11 2014...
.SYNOPSIS...
AN ACTIVE SHOWER AND THUNDERSTORM PERIOD IS ON TAP FOR THE NEXT
WEEK. SHOWERS AND THUNDERSTORMS WILL FAVOR WESTERN AND NORTHERN
NEW MEXICO FOR THE REST OF TODAY AND SATURDAY...BEFORE THE FOCUS
SHIFTS...OR PERHAPS JUST SPREADS...INTO EASTERN NEW MEXICO SUNDAY
THROUGH MUCH OF NEXT WEEK. SEVERAL BACK DOOR COLD FRONT NEXT WEEK
WILL BE A FOCUS FOR PRECIPITATION ACROSS THE PLAINS. THIS WILL
ALSO COOL TEMPERATURES BACK BELOW NORMAL. STORMS WILL MOVE SLOWLY
ALL WEEK...THUS THE POTENTIAL FOR FLOODING EXISTS DAILY...
ESPECIALLY OVER BURN SCARS.
&&
.DISCUSSION...
WATER VAPOR AND VIS SATELLITE IMAGERY SHOWING SUBSTANTIAL DRY AIR
AND SUBSIDENCE MOVING INTO MUCH OF EASTERN AND PORTIONS OF CENTRAL
NM AHEAD OF AN EASTERLY WAVE. MONSOONAL PLUME IS CERTAINLY FOCUSED
ACROSS WESTERN NM WHERE FLASH FLOOD WATCH IS IN PLACE AND PWATS ARE
AT OR JUST ABOVE NORMAL. APPEARS LIKE THE DRY AIR HAS PUSHED FURTHER
WEST THAN MODELS SUGGESTED...BUT THE 17Z HRRR APPEARS TO BE ON TRACK
WITH SHIFTING THE FOCUS FOR PRECIPITATION TONIGHT FURTHER TO THE
NORTHWEST...WHERE THETA-E RIDGE AXIS LIES. HAVE INCREASED POPS IN
THIS AREA AS THESE LOCALES HAVE RECEIVED PLENTY OF SUNSHINE
TODAY...AND WITH GOOD INSTABILITY AND STORM MOTIONS GENERALLY TOWARD
THE WEST...IT MAKES SENSE THAT STORMS FAVOR THAT AREA TONIGHT. THERE
IS ALSO A PRECARIOUS BOUNDARY RIGHT ALONG THE NE NM/SE CO BORDER
THAT HAS RECENTLY SPARKED AN ISOLATED STORM. LOOKS LIKE THIS
BOUNDARY WILL STAY NORTH OF THE AREA...THUS HAVE KEPT POPS AT A
MINIMUM. ABQ AREA WILL BE TRICKY...AS STORMS THUS FAR HAVE STRUGGLED
THAT HAVE FORMED ON THE SANDIAS DUE TO THE DRY AIR...BUT ADDITIONAL
STORMS HAVE DEVELOPED EAST OF THE MTNS AND BASED ON STORM
MOTIONS...SHOULD ARRIVE IN ABQ PRIOR TO 6PM IF THEY HOLD TOGETHER.
THE EASTERLY WAVE SLIDES SOUTH OF THE STATE TONIGHT. THERE WILL
STILL BE SOME DRY AIR IN PLACE OVER THE EAST TOMORROW...BUT THE UPPER
HIGH THAT IS OVER THE NE NOW...WILL START TO SHIFT WNW. THIS WILL
MEAN LITTLE CHANGE FOR STORM COVERAGE AND PLACEMENT FOR SATURDAY.
MOST STORMS WILL TRAVEL WESTWARD...EXCEPT STORMS ACROSS THE NE WHICH
MAY DRIFT EASTWARD. THESE NE STORMS WILL DEVELOP ALONG A WEAK COLD
FRONT THAT WILL GENERALLY STALL ACROSS THE AREA. OUTFLOW BOUNDARIES
LATER IN THE EVENING MAY PUSH IT FURTHER SOUTH HOWEVER.
THE WEAK FRONT ACROSS THE NE LOOKS TO BE REINFORCED A BIT ON
SUNDAY...AND THIS MAY PUSH THE FRONT FURTHER SOUTH. HAVE EXPANDED
CHANCE POPS ACROSS THE NE FOR THIS REASON. OTHERWISE...THE UPPER
HIGH WILL BE CENTERED ACROSS THE GREAT BASIN...WHICH GENERALLY TILTS
THE WEAK MONSOONAL PLUME OVER INTO MORE OF THE STATE.
WITH AN EXISTING BOUNDARY IN PLAY ACROSS THE EAST...HAVE INCREASED
POPS ACROSS THE PLAINS FOR MONDAY. THEN THE STRONGER
FRONT...ASSOCIATED WITH THE STRONG UPPER LOW ACROSS THE GREAT
LAKES...WILL ARRIVE MONDAY NIGHT AND TUESDAY...PUTTING ADDITIONAL
FOCUS FOR STORMS ACROSS THE EAST. THE WEST WILL REMAIN ACTIVE
TOO...ESPECIALLY IF THE FRONT PUSHES THRU THE GAPS.
NORTHWEST FLOW WILL BE IN PLACE OVER NM MID WEEK AS THE PATTERN
BECOMES QUITE AMPLIFIED. THIS IS NOT GOOD IN TERMS OF RECEIVING
MOISTURE FROM THE SOUTH...THE TRADITIONAL MONSOON WAY...BUT REGULAR
DISTURBANCES IN THE NORTHWEST FLOW WILL CONTINUE USHER IN MOISTURE
ACROSS THE EAST BEHIND BACK DOOR FRONTS...AND ONE SUCH STRONG FRONT
LOOKS TO ARRIVE WEDNESDAY NIGHT...WHICH MAY PUSH THRU THE GAPS OF
THE CENTRAL MTN CHAIN ONCE AGAIN. THUS...AN ACTIVE PATTERN WILL
PERSIST THRU THE NEXT WEEK. MODELS ARE HINTING AT REBUILDING THE
UPPER HIGH OVER NM NEXT WEEKEND. STAY TUNED.
34
&&
.FIRE WEATHER...
AN ACTIVE MONSOON MOISTURE PLUME WILL CONTINUE WITH WETTING RAIN
OVER THE WESTERN...CENTRAL AND NORTHERN CENTRAL ZONES THIS AFTERNOON
AND SATURDAY. AN EXPANSION IN THE WETTING RAIN PATTERN WILL COMMENCE
ON SUNDAY WHEN A BACK DOOR FRONT SUPPORTS INCREASED CHANCES OF
PRECIPITATION ACROSS NORTHEASTERN ZONES. A WIDESPREAD WET PATTERN
WILL THEN BE IN PLACE FOR THE WORK WEEK WITH INCREASED CHANCES OF
BURN SCAR FLOODING.
UPPER LEVEL HIGH CURRENTLY IS CENTERED OVER EXTREME EASTERN TEXAS
WITH AN EASTERLY WAVE CENTERED JUST SOUTH OF THE BIG BEND AREA AND
SLOWLY DRIFTING TO THE NORTHWEST. A BROAD AREA OF SUBSIDENCE AHEAD
OF THE WAVE IS USHERING IN MID LEVEL DRY AIR INTO EASTERN NEW
MEXICO...THUS SHUTTING DOWN WETTING RAIN ACROSS THE EASTERN ZONES.
SURFACE MOISTURE REMAINS IN PLACE ACROSS THE EAST WHERE SOME
EXCELLENT RH RECOVERIES ARE EXPECTED TONIGHT...WITH MAINLY GOOD
VALUES ELSEWHERE.
UPCOMING PATTERN CHANGES ARE CURRENTLY DEVELOPING WELL NORTH OF NEW
MEXICO AS AN UPPER RIDGE BUILDS OVER THE WEST COAST AND AN UPPER LOW
DEEPENS OVER CENTRAL CANADA. THIS PATTERN WILL AMPLIFY STARTING
SUNDAY AS THE HIGH CONTINUES TO STRENGTHEN AS THE LOW MOVES TOWARD
THE GREAT LAKES. THE FIRST OF SEVERAL BACK DOOR FRONTS WILL EDGE
INTO THE NORTHEAST ON SUNDAY...WITH COOLER TEMPERATURES...ENHANCED
LOW LEVEL MOISTURE AND INCREASED CHANCES OF WETTING RAIN FROM THE
NORTH CENTRAL MOUNTAIN TO THE NORTHEAST PLAINS. MONSOON PLUME WILL
PERSIST ACROSS THE WEST THUS ONLY THE EXTREME EAST CENTRAL PLAINS
LOOK TO REMAIN DRY.
FOR THE WORK WEEK...THE AMPLIFIED PATTERN PERSISTS WITH HIGH
PRESSURE TO THE WEST AND REGULAR WIND SHIFTS INTO THE NORTHEAST
MAINTAINING MOIST LOW LEVEL EAST TO SOUTHEAST FLOW ACROSS THE
EASTERN PLAINS THROUGH THE WORK WEEK. EXTEND MODELS SHOW REASONABLE
AGREEMENT WITH UPPER LEVEL DISTURBANCES IN THE NORTHWEST FLOW ALOFT
ON EARLY WEDNESDAY AND AGAIN ON THURSDAY. WHILE THERE IS STILL
UNCERTAINTY IN THE TIMING OF SPECIFIC FEATURES...THE CHANCES FOR
WIDESPREAD WETTING RAIN FOR THE WORK WEEK...RESULTING IN POSSIBLE BURN
SCAR FLOODING... ARE FAIRLY CERTAIN. OVERNIGHT RH RECOVERIES LOOK TO
BE GOOD TO EXCELLENT THROUGH THE WORK WEEK. PERIODS OF POOR TO FAIR
VENTILATION CAN BE EXPECTED...ESPECIALLY ACROSS THE NORTH ON
SUNDAY...PORTIONS OF THE WEST ON MONDAY AND TUESDAY...AND THE
NORTHEAST TO EAST WEDNESDAY INTO THURSDAY.
05
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
300 AM EDT SAT JUL 12 2014
.SYNOPSIS...
HIGH PRESSURE OVER THE EASTERN SEABOARD WILL BRING ANOTHER NICE
DAY TO CENTRAL NEW YORK AND NORTHEAST PENNSYLVANIA. A STORM
SYSTEM WILL APPROACH THE REGION FROM THE WEST LATE TONIGHT BRINGING
A CHANCE FOR SHOWERS AND THUNDERSTORMS. THE CHANCE FOR SHOWERS
AND THUNDERSTORMS WILL CONTINUE INTO TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE SLIDING OFF THE EAST COAST WILL ALLOW WARMER AND
MORE HUMID AIR TO WORK INTO THE REGION TODAY. MDL PROFILES
DISPLAY ALOT OF VARIABILITY THIS AFTN W/RESPECT TO POTNL FOR AFTN
CONVECTION. 00Z BUF PROFILE SHOWS A GOOD CAP AT 700 MB WHICH WOULD
TEND TO INHIBIT ACTIVITY. LOW LVL MSTR APPEARS OVERDONE IN THE
NAM...WHILE THE RUC MAY BE DISPLAYING A DRY BIAS W/RESPECT TO LOW
LVL TD/S. GFS PROFILES APPEAR TO BE MOST REASONABLE AND SUGGEST
THE CAP WILL BE ENUF TO SUPPRESS CONVECTION THIS AFTN. IN
ADDN...FCST K`S ARE GNRLY IN THE U20S THIS AFTN. WHILE A STRAY
SHRA CAN`T BE RULED OUT LATE TDA...WE`VE OPTED TO LOWER POPS TO BLO
SLGT CHC. BETTER CHCS FOR CONVECTION WILL COME TWDS DAYBREAK AS
LEADING S/WV AHEAD OF THE DEEPENING GTLAKES UPR LOW APRCHS THE
RGN.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
XPCT SHRA/TSRA TO OVERSPREAD THE RGN SUN MRNG...THEN WORK THRU
DURING THE DAY. CAPES GNRLY IN THE 500-1000 RNG...WITH RATHER
IMPRSV WIND FIELDS. THIS WOULD SUGGEST A LOW END SVR THREAT FOR
MUCH OF THE RGN. AFTER THIS 1ST WAVE WORKS THRU...SOME DIFFS DVLP
IN THE GUIDANCE W/RESPECT TO TIMING AND DVLPMT AHEAD OF THE MAIN
UPR TROF AXIS. XPCT ANOTHER PUSH OF MSTR NWD AS NXT WAVE APRCHS. WE
KEPT HIGH CHC/LIKELY POPS FOR THESE PDS. THE FINGER LAKES...WRN
MOHAWK VLY AND SRN TUG COULD SEE A MAINLY DRY DAY ON MON BEFORE
THE NXT WAVES MOVS IN...SO ONLY INDICATE CHC POPS THERE WITH
HIGHER POPS FURTHER TO THE SOUTH.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
3 AM UPDATE...
NO CHGS TO LONG TERM GRIDS WITH THIS MORNING`S UPDATE. 00Z MODELS
CONTINUE TO SHOW SIGNIFICANT DISCREPANCIES WITH TIMING OF LOPRES
AND ASSOC FROPA WITH LATEST EURO NOT BRINGING CDFNT THRU AREA
UNTIL 12Z WED WHILE 00Z GFS BRINGS IT THRU BY 12Z TUE. UPR LVL
LOWS ARE NOTORIOUSLY HARD TO PREDICT AS THEY TEND TO MEANDER AS
THEY GET CUT OFF FM THE MAIN FLOW, THUS HV MADE NO CHGS TO EXTNDD
FOR THIS REASON.
PREV DISCUSSION BLO...
EXTENDED FORECAST PERIOD WILL BE DOMINATED BY A DEEP UPPER LEVEL
TROF THAT SETTLES OVER THE EASTERN UNITED STATES EARLY IN THE
PERIOD AND PERSISTS THROUGH LATE WEEK. AT THE SFC, A COLD FRONT
WILL TRACK ACROSS THE AREA MONDAY NIGHT INTO TUESDAY. THIS BOUNDARY
WILL BE ACCOMPANIED BY SHOWERS AND THUNDERSTORMS SOME OF WHICH MAY
BE STRONG TO SEVERE DEPENDING ON HOW UNSTABLE THE AIRMASS IS AT THE
TIME OF FROPA. THIS FAR OUT, MEDIUM RANGE MODELS CONTINUE TO SHOW
TIMING DIFFERENCES WITH FRONTAL PASSAGE THEREFORE THERE STILL
REMAINS MUCH UNCERTAINTY TO THE POTENTIAL FOR SEVERE WEATHER. WILL
CONTINUE TO ADVERTISE HIGH CHC/LOW LIKELY POPS MONDAY NIGHT AND
TUESDAY. AFTER SOME LINGERING SHOWERS TUESDAY NIGHT REST OF PERIOD
LOOKS DRY AND COOL WITH SFC HIGH PRES IN THE VCNTY. HIGH TEMPS WED
THROUGH FRIDAY WILL GENERALLY RANGE IN THE 70S.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
06Z UPDATE...
VFR NEXT 24 HOURS FOR ALL TERMINALS WITH THE EXCEPTION OF ELM. MAY
SEE MVFR VSBYS BETWEEN 08Z AND 12Z AT TERMINAL THOUGH POTENTIAL
REMAINS VERY MARGINAL WITH BKN MID-DECK OVER THE CENTRAL NY
TERMINALS AT THIS TIME. VERY LITTLE CONFIDENCE IN SHOWER CHANCES
TODAY AND WILL WITHHOLD FROM ANY TEMPO GROUPS UNTIL THEY CAN
ACTUALLY DEVELOP.
WINDS LIGHT OUT OF THE SOUTHEAST AND/OR LGT/VRB WILL INCREASE TO
BETWEEN 5-8 KTS OUT OF THE SOUTHWEST BY MID-MORNING, DIMINISHING
LATE IN THE DAY.
OUTLOOK...
SATURDAY NIGHT...VFR.
SUN THROUGH TUE NGT...POTENTIAL RESTRICTIONS FROM SHRA/TSRA.
WED...PRIMARILY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...PVN/RRM
AVIATION...PVN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
248 AM EDT SAT JUL 12 2014
.SYNOPSIS...
HIGH PRESSURE OVER THE EASTERN SEABOARD WILL BRING ANOTHER NICE
DAY TO CENTRAL NEW YORK AND NORTHEAST PENNSYLVANIA. A STORM
SYSTEM WILL APPROACH THE REGION FROM THE WEST LATE TONIGHT BRINGING
A CHANCE FOR SHOWERS AND THUNDERSTORMS. THE CHANCE FOR SHOWERS
AND THUNDERSTORMS WILL CONTINUE INTO TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE SLIDING OFF THE EAST COAST WILL ALLOW WARMER AND
MOREE HUMID AIR TO WORK INTO THE REGION TODAY. MDL PROFILES
DISPLAY ALOT OF VARIABILTY THIS AFTN W/RESPECT TO POTNL FOR AFTN
CONVECTION. 00Z BUF PROFILE SHOWS A GOOD CAP AT 700 MB WHICH WOULD
TEND TO INHIBIT ACTIVITY. LOW LVL MSTR APPEARS OVERDONE IN THE
NAM...WHILE THE RUC MAY BE DISPLAYING A DRY BIAS W/RESPECT TO LOW
LVL TD/S. GFS PROFILES APPEAR TO BE MOST REASONABLE AND SUGGEST
THE CAP WILL BE ENUF TO SUPRESS CONVECTION THIS AFTN. IN
ADDN...FCST K`S ARE GNRLY IN THE U20S THIS AFTN. WHILE A STRAY
SHRA CAN`T BE RULED OUT LATE TDA...WE`VE OPTED TO LOWER POPS TO BLO
SLGT CHC. BETTER CHCS FOR CONVECTION WILL COME TWDS DAYBREAK AS
LEADING S/WV AHEAD OF THE DEEPENING GTLAKES UPR LOW APRCHS THE
RGN.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
XPCT SHRA/TSRA TO OVERSPREAD THE RGN SUN MRNG...THEN WORK THRU
DURING THE DAY. CAPES GNRLY IN THE 500-1000 RNG...WITH RATHER
IMPRSV WIND FIELDS. THIS WOULD SUGGEST A LOW END SVR THREAT FOR
MUCH OF THE RGN. AFTER THIS 1ST WAVE WORKS THRU...SOME DIFFS DVLP
IN THE GUIDANCE W/RESPECT TO TIMING AND DVLPMT AHEAD OF THE MAIN
UPR TROF AXIS. XPCT ANOTHER PUSH OF MSTR NWD AS NXT WAVE APRCHS. WE
KEPT HIGH CHC/LIKELY POPS FOR THESE PDS. THE FINGER LAKES...WRN
MOHAWK VLY AND SRN TUG COULD SEE A MAINLY DRY DAY ON MON BEFORE
THE NXT WAVES MOVS IN...SO ONLY INDICATE CHC POPS THERE WITH
HIGHER POPS FURTHER TO THE SOUTH.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
EXTENDED FORECAST PERIOD WILL BE DOMINATED BY A DEEP UPPER LEVEL
TROF THAT SETTLES OVER THE EASTERN UNITED STATES EARLY IN THE
PERIOD AND PERSISTS THROUGH LATE WEEK. AT THE SFC, A COLD FRONT
WILL TRACK ACROSS THE AREA MONDAY NIGHT INTO TUESDAY. THIS BOUNDARY
WILL BE ACCOMPANIED BY SHOWERS AND THUNDERSTORMS SOME OF WHICH MAY
BE STRONG TO SEVERE DEPENDING ON HOW UNSTABLE THE AIRMASS IS AT THE
TIME OF FROPA. THIS FAR OUT, MEDIUM RANGE MODELS CONTINUE TO SHOW
TIMING DIFFERENCES WITH FRONTAL PASSAGE THEREFORE THERE STILL
REMAINS MUCH UNCERTAINTY TO THE POTENTIAL FOR SEVERE WEATHER. WILL
CONTINUE TO ADVERTISE HIGH CHC/LOW LIKELY POPS MONDAY NIGHT AND
TUESDAY. AFTER SOME LINGERING SHOWERS TUESDAY NIGHT REST OF PERIOD
LOOKS DRY AND COOL WITH SFC HIGH PRES IN THE VCNTY. HIGH TEMPS WED
THROUGH FRIDAY WILL GENERALLY RANGE IN THE 70S.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
06Z UPDATE...
VFR NEXT 24 HOURS FOR ALL TERMINALS WITH THE EXCEPTION OF ELM. MAY
SEE MVFR VSBYS BETWEEN 08Z AND 12Z AT TERMINAL THOUGH POTENTIAL
REMAINS VERY MARGINAL WITH BKN MID-DECK OVER THE CENTRAL NY
TERMINALS AT THIS TIME. VERY LITTLE CONFIDENCE IN SHOWER CHANCES
TODAY AND WILL WITHHOLD FROM ANY TEMPO GROUPS UNTIL THEY CAN
ACTUALLY DEVELOP.
WINDS LIGHT OUT OF THE SOUTHEAST AND/OR LGT/VRB WILL INCREASE TO
BETWEEN 5-8 KTS OUT OF THE SOUTHWEST BY MID-MORNING, DIMINISHING
LATE IN THE DAY.
OUTLOOK...
SATURDAY NIGHT...VFR.
SUN THROUGH TUE NGT...POTENTIAL RESTRICTIONS FROM SHRA/TSRA.
WED...PRIMARILY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
LONG TERM...RRM
AVIATION...PVN
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
319 AM CDT SAT JUL 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 319 AM CDT SAT JUL 12 2014
MAIN SHORT TERM CONCERN IS ON PRECIPITATION TRENDS THROUGH THE
EVENING AS WELL AS SEVERE WEATHER POTENTIAL.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A SUBTROPICAL HIGH OVER THE CENTRAL PLAINS AND A DEEP UPPER
TROUGHING COVERING MUCH OF CENTRAL CANADA. A SERIES OF MONSOONAL
SHORTWAVES WERE COMING AROUND THE WEST SIDE OF THE SUBTROPICAL
HIGH...ONE OVER SOUTH CENTRAL SOUTH DAKOTA AND A SECOND IN WYOMING. A
STREAM OF TROPICAL PACIFIC MOISTURE WAS ALSO EVIDENT AROUND THE
SUBTROPICAL HIGH. IN THE LOWER LEVELS...A PLUME OF 15-18C 850MB
DEWPOINTS STRETCHED FROM OKLAHOMA INTO SOUTH DAKOTA AND SOUTHERN
MINNESOTA PER 00Z RAOBS. ALL THIS MOISTURE EQUATES TO PRECIPITABLE
WATER VALUES OF AROUND 2 INCHES FROM SIOUX FALLS AREA SOUTHEAST INTO
CENTRAL ILLINOIS. A ZONE OF 850MB MOISTURE TRANSPORT AHEAD OF THE
MONSOONAL SHORTWAVES ACTING ON THIS MOISTURE...ALONG WITH LOW TO MID
LEVEL FRONTOGENESIS...HAS LED TO SHOWERS AND STORMS IN THAT
PRECIPITABLE WATER MAXIMUM. THIS PRECIPITATION HAS CAUSED THE
MAIN SURFACE WARM FRONT TO GET STUCK IN FAR SOUTHERN IOWA.
SOME OF THE GENERALITIES FOR TODAYS FORECAST. THE 2 MONSOONAL
SHORTWAVES WILL TRACK ACROSS THE FORECAST AREA...HELPING TO PULL THE
850MB MOISTURE TRANSPORT ZONE AND LOW TO MID LEVEL FRONTOGENESIS
NORTHWARD TOWARDS AND POSSIBLY INTO THE AREA. IN ADDITION...AN UPPER
JET STREAK ASSOCIATED WITH THE CENTRAL CANADA UPPER TROUGH IS
PROGGED TO ALIGN ITSELF FROM CENTRAL MN THROUGH LAKE SUPERIOR...
PLACING SOME IF NOT ALL OF THE FORECAST AREA IN THE FAVORABLE RIGHT
ENTRANCE REGION. INSTABILITY WISE...ALONG AND SOUTH OF THE WARM
FRONTAL BOUNDARY 1500-2500 J/KG OF MLCAPE SEEMS REASONABLE TO
DEVELOP THIS AFTERNOON...AS TEMPS CLIMB INTO THE 80S AND DEWPOINTS
HOVER IN THE MID 70S OR SO. PLENTIFUL PRECIPITABLE WATER AROUND AS
WELL AS NOTED IN THE CURRENT WEATHER DISCUSSION...RUNNING AROUND 2
INCHES. THUS...PLENTY OF MOISTURE EXISTS TO COMBINE WITH DYNAMIC AND
THERMODYNAMIC FORCING TO PRODUCE CONVECTION. 0-6KM AND 0-3KM SHEAR
VALUES REMAIN FAVORABLE FOR ORGANIZED SEVERE CONVECTION...ON THE
ORDER OF 40-50 KT AND 30-45 KT RESPECTIVELY. MUCH OF THIS SHEAR IS
CONFINED ABOVE 1 KM AS THE WINDS BELOW ARE FAIRLY LIGHT. STILL HAVE
CYCLONIC CURVATURE IN THE HODOGRAPH...THOUGH. BASED ON THE
AFOREMENTIONED PARAMETERS...DAMAGING WINDS AND HEAVY RAINS WOULD BE
THE MAIN CONCERNS...WITH SOME MARGINALLY SEVERE HAIL AND AN OUTSIDE
CHANCE OF A TORNADO. THE HIGHER SHEAR AND DRYING SOILS AS OF LATE
SHOULD HELP TO KEEP ANY FLOOD CONCERN LOCALIZED...IN AGREEMENT TOO
WITH THE DAY 1 EXCESSIVE RAINFALL OUTLOOK.
NOW...THE CRITICAL UNCERTAINTIES...
1. TIMING AND INTENSITY OF THE 2 MONSOONAL SHORTWAVES...WHICH
IMPACTS THE MOVEMENT OF THE 850MB MOISTURE TRANSPORT ZONE AND LOW TO
MID LEVEL FRONTOGENESIS. WHERE THAT MOISTURE TRANSPORT NOSE...F-GEN
ZONE...AND DPVA FROM THE SHORTWAVES WILL MODULATE WHERE THE
CONVECTION ENDS UP. MODELS ARE ALL OVER THE BOARD WITH THESE
SHORTWAVES...LEADING TO LOWERED CONFIDENCE.
2. HOW FAR NORTH THE WARM FRONT CAN MAKE IT WHICH IMPACTS THE ZONE
OF INSTABILITY AND THUS HOW FAR NORTH THROUGH THE FORECAST AREA A
SEVERE RISK EXISTS. ITEM NUMBER 1 ABOVE WILL IMPACT THE WARM FRONT.
DESPITE THE UNCERTAINTIES ABOVE...IT STILL APPEARS THROUGH THIS
EVENING LOCATIONS SOUTH OF I-90 STAND TO SEE THE HIGHEST CHANCE FOR
CONVECTION. ADDITIONALLY...SEVERE WEATHER IS GOING TO HAPPEN BETWEEN
I-80 AND I-90 AFTER 2 PM TODAY...CONSISTING OF SUPERCELLS AND BOW
SEGMENTS. PINNING DOWN THE LOCATION ANY FINER THAN THAT IS
PROBLEMATIC AT THIS TIME. LATER FORECAST UPDATES SHOULD BE ABLE TO
REFINE THE LOCATION AND TIMING.
HAVE ADJUSTED THE MORNING PORTION OF THE FORECAST TO FOLLOW TRENDS
IN THE HRRR...WHILE A MODEL CONSENSUS DOMINATES THE AFTERNOON AND
EVENING. NOTE THAT THERE COULD ALSO BE SOME SURFACE BASED CONVECTION
THAT FIRES OVER WEST CENTRAL WI THIS AFTERNOON ALONG A SOUTHEASTWARD
MOVING COLD FRONT. THE AFOREMENTIONED CONSENSUS JUST HAPPENS TO BE
SIMILAR TO THE 00Z NSSL WRF-ARW. HEADING INTO TONIGHT...THERE WILL
BE A NORTHWEST TO SOUTHEAST DRYING TREND AS THE SHORTWAVES PUSH OFF
TO THE EAST... USHERING IN SUBSIDENCE AND MUCH DRIER PRECIPITABLE
WATER VALUES.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 319 AM CDT SAT JUL 12 2014
A GRADUAL DESCENT OF THE DEEP UPPER TROUGH OVER CENTRAL CANADA INTO
THE FORECAST AREA REMAINS ON TRACK BETWEEN SUNDAY AND MONDAY...WITH
THE TROUGH SLOWLY PUSHING TO THE EAST ON TUESDAY. AS THIS
OCCURS...THERE ARE COUPLE OF ISSUES TO CONTEND WITH...
1. POTENTIAL FOR CONVECTION ON SUNDAY. A SURFACE COLD FRONT IS
PROGGED TO DROP THROUGH THE AREA...THOUGH THERE DOES NOT APPEAR TO
BE MUCH CONVERGENCE ON IT. THE 12.00Z ECMWF/NAM/REGIONAL
CANADIAN/HIRES ARW AND NMM ARE DRY...WHILE THE 12.00Z GFS HAS
REDUCED ITS QPF EVEN MORE. THE GFS STILL HAS TOO HIGH SURFACE
DEWPOINTS IN WHAT SHOULD BE A FAVORABLE MIXING REGIME...THUS PREFER
THE DRIER IDEA.
2. RAIN CHANCES MONDAY THROUGH TUESDAY. AN UPPER LOW WITHIN THE
TROUGH WILL SLIDE ACROSS NORTHERN WI MONDAY EVENING. DPVA FORCING
AHEAD OF THE UPPER LOW AND DAYTIME INSTABILITY SHOULD PROMOTE PLENTY
OF SHOWER ACTIVITY...ESPECIALLY ALONG AND NORTH OF HIGHWAY 29 CLOSER
TO THE UPPER LOW. SOME SHOWER ACTIVITY COULD CONTINUE INTO
TUESDAY...MAINLY IN WISCONSIN CLOSER TO THE UPPER TROUGH AXIS.
3. TEMPERATURES MONDAY AND TUESDAY. 850MB TEMP ANOMALIES PLUMMET TO
2 TO 2.5 STANDARD DEVIATIONS BELOW NORMAL DURING THIS PERIOD...OR
GENERALLY IN THE 4-7C RANGE. THESE READINGS GENERALLY SUPPORT HIGHS
IN THE 60S. HOWEVER...THERE ARE SOME MODEL SUGGESTIONS ON TUESDAY
THAT...DEPENDING ON HOW QUICK THE TROUGH PUSHES EAST...BOTH THE
850MB TEMP AND ACTUAL HIGH COULD BE A LITTLE WARMER. LOWS WILL BE
HELD UP SOMEWHAT BY BOTH CLOUDS AND A NORTHWESTERLY BREEZE. NEEDLESS
TO SAY...ITS GOING TO FEEL MORE LIKE FALL VERSUS SUMMER.
AFTER TUESDAY AND THROUGH THE END OF THE WEEK...EXPECT A LONG DRY
PERIOD AS SURFACE HIGH PRESSURE DOMINATES AND 500MB HEIGHTS RISE.
HOWEVER...THE 12.00Z GFS SHOWS DIURNALLY DRIVEN WIDESPREAD LIGHT
PRECIP WEDNESDAY...THURSDAY AND FRIDAY. THE MODEL APPEARS TO BE
SUFFERING FROM OVER-DOING EVAPOTRANSPIRATION...NOTED IN ITS SURFACE
DEWPOINT FIELD...AND THUS CONVECTS EASIER. THUS...HAVE IGNORED IT
AND STAYED WITH THE DRY ECMWF/CANADIAN.
TEMPERATURES WILL GRADUALLY WARM THROUGH THE WEEK...GETTING CLOSE TO
NORMAL FOR THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1143 PM CDT FRI JUL 11 2014
THE AREA OF MVFR CLOUDS HAS DISSIPATED OR LIFTED UP TO VFR
CEILINGS WITH THE BACK EDGE WORKING STEADILY EAST AND BY 06Z THE
CLOUDS SHOULD BE PAST KLSE. THIS INCREASES THE PROBABILITIES THAT
SOME FOG CAN FORM OVERNIGHT BUT AT THE SAME TIME...HIGH CLOUDS ARE
BEGINNING TO SPREAD IN FROM THE WEST...WHICH WOULD DECREASE THE
FOG PROBABILITIES. THE HIGH CLOUDS APPEAR TO BE DISSIPATING SOME
AS THEY COME INTO THE AREA AND IF THIS TREND CONTINUES...SOME FOG
COULD FORM SO HAVE HELD ONTO THIS IN BOTH FORECASTS. A WARM FRONT
SITS ACROSS SOUTHERN IOWA AND AS THE MOISTURE TRANSPORT INCREASES
INTO THIS OVERNIGHT SOME CONVECTION IS EXPECTED TO FORM ALONG THIS
BOUNDARY. THIS COMBINED WITH THE ONGOING ACTIVITY OVER NEBRASKA
AND SOUTH DAKOTA COULD DRIFT NORTHWARD INTO THE AREA EARLY
SATURDAY MORNING. THIS IS THE TREND THAT HAS BEEN SHOWN BY THE
LAST FEW RUNS OF THE HRRR AND HAVE INTRODUCED A VCSH FOR THIS BY
MID MORNING WITH A VFR CEILING. THE BETTER CHANCES FOR CONVECTION
WILL BE TIED TO THE SHORT WAVE TROUGH COMING ACROSS WYOMING AND
MONTANA. THE 12.00Z NAM SHOWS CONVECTION DEVELOPING AROUND MID DAY
OVER SOUTH DAKOTA AND NEBRASKA AND THEN MOVING EAST INTO THE AREA
LATE IN THE AFTERNOON INTO THE EVENING. BASED ON THIS
TIMING...HAVE PUSHED THE TIMING OF THE VCTS BACK A LITTLE AT BOTH
SITES BUT DID INTRODUCE A MVFR CEILING AT KRST.
&&
.HYDROLOGY...
ISSUED AT 319 AM CDT SAT JUL 12 2014
THERE IS A CONCERN FOR FLASH FLOODING THIS AFTERNOON INTO THIS
EVENING...PRIMARILY ACROSS NORTHEAST IOWA AND FAR SOUTHWEST
WISCONSIN. STORMS IN THIS REGION WILL BE CAPABLE OF PRODUCING VERY
HEAVY RAIN DUE TO A NEARLY TROPICAL AIRMASS IN PLACE. NO FLASH
FLOOD WATCH IS BEING ISSUED AT THIS TIME...THOUGH...BECAUSE OF
1. STRONG 0-3/0-6KM SHEAR WHICH SHOULD KEEP STORMS PROGRESSIVE
2. ANTECEDANT CONDITIONS HAVE DRIED OUT AND CAN TAKE MORE WATER
NEVERTHELESS...SINCE STORMS WILL HAVE HIGH RAINFALL RATES...THERE
COULD BE A NEED FOR A FLASH FLOOD WARNING OR TWO.
&&
.CLIMATE...
ISSUED AT 319 AM CDT SAT JUL 12 2014
RECORD COOL HIGH TEMPERATURES ARE POSSIBLE MONDAY AND TUESDAY AS AN
UNSEASONABLY COLD AIRMASS SETTLES OVER THE UPPER MISSISSIPPI RIVER
VALLEY.
FOR LA CROSSE...
MONDAY....FORECAST HIGH 69. RECORD 65 IN 1994
TUESDAY...FORECAST HIGH 68. RECORD 68 IN 1962
FOR ROCHESTER...
MONDAY....FORECAST HIGH 64. RECORD 64 IN 1952
TUESDAY...FORECAST HIGH 67. RECORD 67 IN 1962
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
HYDROLOGY...AJ
CLIMATE...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1144 PM CDT FRI JUL 11 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 332 PM CDT FRI JUL 11 2014
MAIN FORECAST CONCERNS ARE ON SEVERE THUNDERSTORM POTENTIAL ON
SATURDAY INTO SATURDAY EVENING. FOCUS THEN TURNS TO UNSEASONABLY
COLD TEMPERATURES EARLY NEXT WEEK.
SURFACE OBSERVATIONS SHOWED A COLD FRONT EXTENDING FROM NORTHWEST
MINNESOTA INTO EXTREME NORTHEAST SOUTH DAKOTA...EDGING SOUTHEAST.
A BROAD WARM AIR ADVECTION REGIME WAS IN PLACE OVER THE UPPER
MISSISSIPPI RIVER VALLEY WITH A SHORTWAVE MOVING THROUGH AND
EXITING THE AREA LATE THIS AFTERNOON . THIS WAVE BROUGHT SHOWERS
AND ISOLATED THUNDERSTORMS TO PARTS OF THE REGION TODAY. A WARM
FRONT IS EXPECTED TO LIFT INTO CENTRAL IOWA/NORTHERN ILLINOIS
TONIGHT AND WILL BE THE FOCUS FOR MORE SHOWERS AND THUNDERSTORMS.
ACROSS THE LOCAL AREA IT SHOULD BE PRETTY QUIET TONIGHT OUTSIDE
OF SEEING MOSTLY CLOUDY SKIES AND POSSIBLY SOME PATCHY FOG. THE
CLOUD COVER AND SOUTH WINDS SHOULD HELP HOLD TEMPERATURES IN THE
MID TO UPPER 60S.
A SHORTWAVE ROUGH THEN RACES EAST ACROSS SOUTH DAKOTA EARLY SATURDAY
MORNING AND PUSHES THROUGH THE FORECAST AREA LATE SATURDAY MORNING
THROUGH SATURDAY AFTERNOON. THIS WAVE WILL INTERACT WITH THE COLD
FRONT EDGING INTO THE FORECAST AREA FROM THE NORTHWEST AND THE WARM
FRONT OVER PORTIONS OF NORTHERN IOWA INTO FAR SOUTHWEST WISCONSIN.
WHILE THIS FEATURE WILL GENERATE WIDESPREAD SHOWERS AND
THUNDERSTORMS OVER THE REGION THERE IS SOME UNCERTAINTY REGARDING
SEVERE WEATHER POTENTIAL. THE MAIN CONCERN LOOKS TO BE HEAVY RAIN
THROUGH MIDDAY ON SATURDAY THEN...IF THE INSTABILITY CAN LIFT
NORTH INTO LOCATIONS ALONG AND SOUTH OF INTERSTATE 90...WE COULD
SEE THE THREAT FOR DAMAGING WINDS AND LARGE HAIL. WHILE 0-1 KM
SHEAR ISN/T IMPRESSIVE...IT COULD POSSIBLY BE ENHANCED OVER
PORTIONS OF NORTHEAST IOWA AND EXTREME SOUTHWEST WISCONSIN CLOSER
TO WARM FRONT. THIS WOULD LEAD TO THE POSSIBILITY OF AN ISOLATED
TORNADO OVER THESE AREAS. THERE IS EXCELLENT UPPER LEVEL SUPPORT
FOR SHOWERS AND THUNDERSTORMS TOMORROW THANKS TO THE RIGHT
ENTRANCE REGION OF AN UPPER JET STREAK POSITIONED OVER THE
REGION SO HAVE INCREASED PRECIPITATION CHANCES SIGNIFICANTLY. 0-6
KM BULK SHEAR IS WEAK SATURDAY MORNING BUT THEN RAMPS UP SATURDAY
AFTERNOON WHEN VALUES INCREASE TO 40 TO 50 KTS. MOST OF THE SHEAR
IS LOCATED IN THE 1 TO 7 KM LAYER...SO EVEN ELEVATED STORMS COULD
POSSIBLY BECOME SEVERE. PRECIPITABLE WATER VALUES INCREASE TO 1.5
TO 2.0 INCHES TONIGHT OVER MUCH OF THE FORECAST AREA AND REMAIN IN
THIS RANGE THROUGH TOMORROW AFTERNOON FOR LOCATIONS ALONG AND
SOUTH OF INTERSTATE 90. THESE PW VALUES COMBINED WITH WARM CLOUD
DEPTH OF 3.5 TO 4 KM WILL INCREASE THE POTENTIAL FOR HEAVY
RAINFALL. WILL HAVE TO KEEP A CLOSE EYE ON HEAVY RAIN POTENTIAL
OVER NORTHEAST IOWA INTO SOUTHWEST WISCONSIN. THE FRONT.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 332 PM CDT FRI JUL 11 2014
THE FRONT THEN PUSHES SOUTHEAST OF THE FORECAST AREA SATURDAY
EVENING WITH SHOWERS AND THUNDERSTORM ENDING. A SECONDARY COLD FRONT
THEN DROPS SOUTH ACROSS THE AREA ON SUNDAY AND MAY GENERATE A
COUPLE OF SHOWERS AND THUNDERSTORMS BUT INSTABILITY IS RATHER
LACKING WITH THIS FEATURE. A POTENT UPPER TROUGH WILL DROP SOUTH
OUT OF CANADA AND INTO THE UPPER MISSISSIPPI RIVER VALLEY SUNDAY
NIGHT INTO MONDAY BRINGING UNSEASONABLY COLD AIR INTO THE REGION
ALONG WITH CHANCES FOR RAIN SHOWERS. 850 MB TEMPERATURES FALL TO
AROUND 4 C MONDAY NIGHT INTO TUESDAY WITH STANDARDIZED ANOMALIES
OF -2.0 TO -2.5 PLACING US IN RECORD COLD
TEMPERATURES...ESPECIALLY FOR HIGH TEMPERATURES ON MONDAY INTO
TUESDAY. TUESDAY LOOKS TO BE THE COLDEST DAY WHEN HIGHS WILL
STRUGGLE TO GET OUT OF THE LOWER TO MID 60S. THE TROUGH EXIT THE
REGION TUESDAY NIGHT INTO WEDNESDAY . TEMPERATURES THEN START TO
MODERATE WEDNESDAY THROUGH THE END OF THE WORK WEEK WITH HIGHS
CLIMBING BACK INTO THE 70S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1143 PM CDT FRI JUL 11 2014
THE AREA OF MVFR CLOUDS HAS DISSIPATED OR LIFTED UP TO VFR
CEILINGS WITH THE BACK EDGE WORKING STEADILY EAST AND BY 06Z THE
CLOUDS SHOULD BE PAST KLSE. THIS INCREASES THE PROBABILITIES THAT
SOME FOG CAN FORM OVERNIGHT BUT AT THE SAME TIME...HIGH CLOUDS ARE
BEGINNING TO SPREAD IN FROM THE WEST...WHICH WOULD DECREASE THE
FOG PROBABILITIES. THE HIGH CLOUDS APPEAR TO BE DISSIPATING SOME
AS THEY COME INTO THE AREA AND IF THIS TREND CONTINUES...SOME FOG
COULD FORM SO HAVE HELD ONTO THIS IN BOTH FORECASTS. A WARM FRONT
SITS ACROSS SOUTHERN IOWA AND AS THE MOISTURE TRANSPORT INCREASES
INTO THIS OVERNIGHT SOME CONVECTION IS EXPECTED TO FORM ALONG THIS
BOUNDARY. THIS COMBINED WITH THE ONGOING ACTIVITY OVER NEBRASKA
AND SOUTH DAKOTA COULD DRIFT NORTHWARD INTO THE AREA EARLY
SATURDAY MORNING. THIS IS THE TREND THAT HAS BEEN SHOWN BY THE
LAST FEW RUNS OF THE HRRR AND HAVE INTRODUCED A VCSH FOR THIS BY
MID MORNING WITH A VFR CEILING. THE BETTER CHANCES FOR CONVECTION
WILL BE TIED TO THE SHORT WAVE TROUGH COMING ACROSS WYOMING AND
MONTANA. THE 12.00Z NAM SHOWS CONVECTION DEVELOPING AROUND MID DAY
OVER SOUTH DAKOTA AND NEBRASKA AND THEN MOVING EAST INTO THE AREA
LATE IN THE AFTERNOON INTO THE EVENING. BASED ON THIS
TIMING...HAVE PUSHED THE TIMING OF THE VCTS BACK A LITTLE AT BOTH
SITES BUT DID INTRODUCE A MVFR CEILING AT KRST.
&&
.CLIMATE...
ISSUED AT 332 PM CDT FRI JUL 11 2014
RECORD COOL HIGH TEMPERATURES ARE POSSIBLE ON TUESDAY AS AN
UNSEASONABLY COLD AIRMASS SETTLES OVER THE UPPER MISSISSIPPI
RIVER VALLEY. FORECAST HIGH TEMPERATURES FOR TUESDAY ARE 65 AT
ROCHESTER AND 66 AT LA CROSSE. THESE TEMPERATURES WOULD BREAK THE
RECORD LOWEST HIGH TEMPERATURES FOR JULY 15TH. THE OLD RECORDS ARE
68 AT LA CROSSE SET BACK IN 1962 AND 67 AT ROCHESTER ALSO SET
BACK IN 1962.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...04
CLIMATE...WETENKAMP
AREA FORECAST DISCUSSION
NWS PUEBLO CO
441 AM MDT SAT JUL 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 441 AM MDT SAT JUL 12 2014
A SHORTWAVE TROF PASSING TO THE NORTH OF THE AREA TODAY WL SEND A
FRONT INTO NE CO...WHICH IS THEN EXPECTED TO MAKE ITS WAY INTO SERN
CO LATE THIS AFTERNOON AND EVENING. CURRENTLY THIS EARLY MORNING
THERE ARE SOME LIGHT ECHOES OVER THE CONTDVD...SO WL HAVE SOME ISOLD
POPS IN THAT AREA FOR THE EARLY MORNING HOURS. HI RES FORECAST
MODELS THEN SHOW CONVECTION DEVELOPING OVR THE MTNS IN THE LATE
MORNING HRS. THE PCPN THEN SPREADS OVR THE SAN LUIS VALLEY AND I-25
CORRIDOR IN THE EARLY AFTERNOON...AND THEN OVR THE SOUTHEAST PLAINS
LATE IN THE AFTERNOON AND IN THE EVENING HOURS. THE WRF AND RAP
SHOW EL PASO COUNTY...ESPECIALLY NRN AND WRN PORTIONS POTENTIALLY
GETTING HIT WITH HEAVY RAIN IN THE LATE AFTERNOON AND EARLY EVENING
HOURS WITH LOW TO MID LEVEL NORTHEAST WINDS. WITH THE FLOW ALOFT
EXPECTED TO ONLY BE AROUND 5 KTS...THAT WOULD LEAD TO SLOW MOVING
STORMS AND THE THREAT OF HEAVY RAIN. AREA BURN SCARS WL BE A CONCERN
IF HEAVY RAIN DEVELOPS...AS WELL AS PORTIONS OF ERN EL PASO COUNTY
THAT RECEIVED HEAVY RAIN LAST EVENING.
IN THE EARLY EVENING HOURS AS THE FRONT MOVES SOUTH TO THE RATON
MESA AREA...THE HEAVY RAIN POTENTIAL MAY SHIFT TO THAT AREA FOR THE
REST OF THE EVENING. THE WRF THEN DECREASES OR END MOST OF THE PCPN
AFTER 06Z. HOWEVER...THE 06Z RUN OF THE NAM12 HAS COME IN WITH
HEAVY RAIN POTENTIAL THRU THE NIGHT OVR THE WET AND SANGRE DE CRISTO
MTNS AND THE ADJACENT LOWER ELEVATIONS. THE NAM IS SHOWING AROUND
2.5 INCHES OF PCPN OVR THE WET MTNS IN THE PERIOD FROM 00Z-12Z
SUN...WITH ABOUT 1-1.5 INCHES OVR SW PUEBLO...HUERFANO AND WRN LAS
ANIMAS COUNTIES...WITH MID LEVEL EASTERLY FLOW AROUND 15 KTS. THE
GFS ALSO PEGS THE SANGRES AND WET AS AN AREA THAT COULD SEE SOME
HEAVIER RAIN OVERNIGHT...HOWEVER ITS AMOUNTS ARE MUCH LESS WHEN
COMPARED TO THE NAM. SINCE THE HRRR AND RAP DO NOT GO OUT THROUGH
THE NIGHT PERIOD YET...WILL JUST GO WITH SOME SCT POPS OVERNIGHT
OVER THE SANGRES AND WETS AND NEARBY LOWER ELEVATIONS AND LET THE
NEXT SHIFT EVALUATE THE HI RES MODEL DATA AS IT COMES IN FOR THE
OVERNIGHT HOURS...ALONG WITH THE NEXT RUN OF THE NAM.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 441 AM MDT SAT JUL 12 2014
...COOL AND WET WEATHER EXPECTED INTO THE MIDDLE OF WORK WEEK...
SUNDAY-SUNDAY NIGHT...WEAK TO MODERATE NORTH TO NORTHWEST FLOW ALOFT
PROGGED ACROSS THE REGION WITH HIGH AMPLITUDE RIDGING BUILDING BACK
ACROSS THE WEST COAST AND GREAT BASIN AS AN UNSEASONABLY STRONG
UPPER LOW DIGS INTO THE UPPER GREAT LAKES REGION. LATEST MODELS ARE
INDICATING SHORT WAVE ENERGY TRANSLATING DOWN THE EASTERN PERIPHERY
OF THE RIDGE ACROSS THE NORTHERN ROCKIES AND NORTHERN HIGH PLAINS
WITH SECONDARY SURGE OF COOL AIR BUILDING INTO THE CENTRAL HIGH
PLAINS AND INTO EASTERN COLORADO. MODELS ARE ALSO INDICATING THE
MAIN MONSOONAL MOISTURE PLUME BEING SHUNTED SOUTH AND WEST OF THE
AREA WITH SOME DRIER AIR EMBEDDED WITHIN THE DEVELOPING NORTHERLY
FLOW SLOWLY WORKING INTO NORTHWESTERN COLORADO. HOWEVER....PRECIP
WATER...IS PROGGED TO REMAIN HIGH ACROSS THE AREA WITH READINGS
BETWEEN 0.75 INCHES AND 1.5 INCHES...GREATEST ACROSS THE EASTERN
PLAINS. THERE COULD BE SOME ONGOING SHOWERS ACROSS THE AREA EARLY
SUNDAY MORNING AS SECONDARY SURGE OF COOL AIR AND LOW LEVEL MOISTURE
BACKS INTO EASTERN COLORADO. WITH AMPLE MOISTURE IN PLACE...ALONG
WITH STRONG SOLAR HEATING AND SOME INCREASED UVV ASSOCIATED WITH
PASSING SHORT WAVE...SHOULD SEE SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS DEVELOPING ACROSS THE HIGHER TERRAIN LATE SUNDAY
MORNING AND AFTERNOON...WITH SCATTERED STORMS SPREADING ACROSS THE
ADJACENT PLAINS THROUGH THE FAR EASTERN PLAINS SUNDAY AFTERNOON AND
EVENING. STORMS WILL BE GENERALLY SLOW MOVING WITH LOCALLY HEAVY
RAINFALL LEADING TO POSSIBLE FLASH FLOODING CONCERNS...ESPECIALLY
ACROSS AREA BURN SCARS. THERE MAY ALSO BE ENOUGH SHEAR ACROSS THE
EASTERN PLAINS FOR A FEW STRONGER STORMS PRODUCING HAIL AND STRONG
WIND GUSTS.
MONDAY-WEDNESDAY...MODERATE NORTHWESTERLY FLOW CONTINUES ACROSS THE
REGION INTO THE MIDDLE OF WORK WEEK WITH THE HIGH AMPLITUDE UPPER
RIDGE PERSISTING ACROSS THE WEST COAST AND GREAT BASIN AS THE
UNSEASONABLY STRONG UPPER LOW OVER THE UPPER GREAT LAKES REGION DIGS
INTO THE CENTRAL CONUS. DRIER AIR EMBEDDED WITHIN THE FLOW ALOFT
CONTINUES TO SLOWLY WORK INTO WESTERN COLORADO...THOUGH PRECIP WATER
LOOKS TO REMAIN HIGH...ESPECIALLY ACROSS THE EASTERN MTS AND PLAINS
WITH CONTINUED MOIST EASTERLY UPSLOPE FLOW IN PLACE AS COOL CANADIAN
HIGH PRESSURE BUILDS THROUGH THE HIGH PLAINS STATES. AGAIN WITH THE
AMPLE MOISTURE IN PLACE...GENERALLY DIURNAL SCATTERED TO NUMEROUS
THUNDERSTORMS CAN BE EXPECTED ACROSS THE AREA...WITH BEST COVERAGE
OVER AND NEAR THE MTS. WITH THE MODERATE FLOW ALOFT...STORMS WILL BE
MOVING...HOWEVER LOCALLY HEAVY RAINFALL TO REMAIN POSSIBLE. WITH
FAIRLY CLOUDY CONDITIONS AND THE MOIST AND COOL UPSLOPE FLOW...
TEMPERATURES ARE EXPECTED TO BE BELOW TO WELL BELOW SEASONAL
AVERAGES THROUGH THE PERIOD.
THURSDAY-FRIDAY...A SLOW WARMING AND DRYING TREND IN THE OFFING INTO
THE UPCOMING WEEKEND WITH MORE WESTERLY FLOW ALOFT DEVELOPING AS
UPPER RIDGE FLATTENS ACROSS THE GREAT BASIN. ENOUGH MOISTURE REMAINS
TO KEEP ISOLATED TO SCATTERED POPS IN THE FORECAST...WITH BEST
COVERAGE REMAINING ACROSS THE MTS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 441 AM MDT SAT JUL 12 2014
COULD SEE SOME STRATUS THIS MORNING AT KCOS AND KPUB...OTHERWISE
EXPECTED MAINLY VFR CONDITIONS AT THESE SITES TODAY AND TONIGHT.
HOWEVER...WITH THE POTENTIAL FOR SOME HEAVY RAIN THIS AFTERNOON AND
EVENING THERE COULD BE BRIEF PERIODS OF MVFR CONDITIONS ASSOCIATED
WITH THE RAIN. KALS SHOULD GENERALLY SEE VFR CONDITIONS TODAY AND
TONIGHT...BUT IT THUNDERSTORMS MOVE OVER THE AREA...THERE COULD BE
BRIEF PERIODS OF MVFR CONDITIONS AS A RESULT OF HEAVY RAIN.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...28
LONG TERM...MW
AVIATION...28
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
941 AM EDT SAT JUL 12 2014
.DISCUSSION...
ATLANTIC RIDGE AXIS AT THE SURFACE WILL REMAIN JUST NORTH OF THE
REGION AND WILL KEEP LOW LEVEL WINDS OUT OF THE E/SE ACROSS
CENTRAL FLORIDA. THIS FLOW WILL ALLOW THE EAST COAST SEA BREEZE TO
DEVELOP EARLY AND MOVE WELL INLAND THROUGH THE AFTERNOON. MORNING
SOUNDINGS VERIFY GFS PW MODEL OUTPUT NICELY SHOWING A BAND OF DRIER
AIR ACROSS CENTRAL PORTIONS OF THE AREA (1.5" AT XMR) AND DEEPER
MOISTURE INTO NORTH FLORIDA AND MOVING INTO THE TREASURE COAST
(AROUND 2"). LOCAL WRF AND HRRR INDICATE THIS DRIER AIR MY LIMIT
CONVECTION ACROSS BREVARD COUNTY. HOWEVER STILL EXPECTING
INCREASING SHOWER AND THUNDERSTORM COVERAGE OVER THE INTERIOR
ESPECIALLY INLAND OF THE TREASURE COAST AND NEAR AND WEST OF THE
I-4 CORRIDOR FROM MID TO LATE AFTERNOON. A FEW STRONG STORMS
CONTINUE TO BE POSSIBLE...MAINLY OVER THE INTERIOR. HIGHS WILL
REACH THE UPPER 80S ALONG THE COAST TO AROUND 90 DEGREES INLAND.
&&
.AVIATION...VFR CONDS WITH TEMPO IFR/MVFR CONDS EXPECTED WITH
ISO/SCT SHRA/TSRA ALONG AND INLAND OF THE WESTWARD MOVING EAST
COAST SEA BREEZE. CONVECTION WILL BEGIN TO DEVELOP ALONG THE COAST
BY LATE MORNING/EARLY AFTERNOON AND THEN INCREASE IN COVERAGE
ACROSS THE INTERIOR THROUGH THE REMAINDER OF THE DAY. THIS
ACTIVITY WILL DIMINISH OVER THE INTERIOR THROUGH THE EVENING
HOURS.
&&
.MARINE...EAST/SOUTHEAST WINDS WILL OCCUR OVER THE WATERS TODAY
AROUND 10 KNOTS OR LESS WITH SEAS 2 TO 3 FEET. DESPITE ISOLATED
STORMS OVER THE WATERS THIS MORNING...THREAT FOR OFFSHORE MOVING
STORMS INTO THE AFTERNOON LOOKS VERY LOW. BEST CHANCE WOULD EXIST
INTO EARLY AFTERNOON NORTH OF THE CAPE.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
WEITLICH/GLITTO
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
720 AM EDT SAT JUL 12 2014
.PREV DISCUSSION... /ISSUED 433 AM EDT SAT JUL 12 2014/
SHORT TERM /TODAY THROUGH SUNDAY/...
WEAK BOUNDARY STILL SITUATED ACROSS CENTRAL GA THIS MORNING. THE
BOUNDARY IS VERY DIFFUSE AND IS ONLY BARELY NOTED IN THE TEMP/DEW
FIELDS. REGIONAL RADAR SHOWS ALL THE EARLIER SHOWER ACTIVITY HAS
DIMINISHED ACROSS THE CWFA EARLY THIS MORNING.
POP COVERAGE SHOULD BE LESS TODAY THAN IN PREVIOUS DAYS. THE FRONT
WILL CONTINUE TO BECOME MORE DIFFUSE WHILE PUSHING SOUTHWARD AS HIGH
PRESSURE ACROSS THE MIDDLE ATLANTIC BUILDS DOWN THE SPINE OF THE
APPALACHIAN MOUNTAINS. WILL HAVE THE HIGHEST POPS IN THE SOUTHERN
QUARTER OF THE CWFA...NEAREST THE SURFACE BOUNDARY. IN
ADDITION...THE HRRR IS SHOWING SOME ISOLD/LOW END SCT DEVELOPMENT
ACROSS THE HIGHER TERRAIN THIS AFTERNOON.
PWATS ARE A LITTLE HIGHER THAN YESTERDAY...WITH THE DEEPEST MOISTURE
STILL SOUTH OF THE WEAKENING BOUNDARY. HOWEVER...WITH BL WINDS AT OR
BLO 15 KT...STORM MOVEMENT SHOULD BE SLOW. THIS MAY ALSO LEAD TO ANY
STORMS DEVELOPING ACROSS NE GA TO STAY LOCKED ON THE HIGHEST
TERRAIN...LEADING TO LOCALLY HEAVY RAINFALL.
DO THINK CONVECTION WILL MOSTLY BE DIURNAL IN NATURE...AND BEGIN
DIMINISHING WITH THE SETTING SUN. CONVECTION SHOULD BE PULSE...WITH
HIGH CAPE AND LOW SHEAR. MID LEVEL LAPSE RATES REMAIN WEAK...AND
CAN`T FIND ANY SIGNIFICANT SHORTWAVES IN THE FLOW. SO...WIDESPREAD
SEVERE THUNDERSTORMS ARE NOT ANTICIPATED...EITHER TODAY OR SUNDAY
BUT A FEW STRONG STORMS WILL HAVE THE POTENTIAL TO PRODUCE LOCALLY
HEAVY RAINFALL AND GUSTY WINDS. THERE IS A LITTLE POTENTIAL FOR AN
ISOLD SEVERE STORM EACH DAY. CONVECTIVE COVERAGE FOR SUNDAY SHOULD
BE EVEN LESS THAN TODAY.
WITH LESSER CONVECTIVE COVERAGE...TEMPS WILL BE WARMER.
NLISTEMAA
LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
NO IMPACT WEATHER EXPECTED IN THE LONG TERM PERIOD. PATTERN STILL
EXPECTED TO BECOME DOMINATED BY LARGE UPPER TROUGH OVER THE ERN
CONUS BY TUES AND PERSIST THRU FRIDAY. 00Z MED RANGE MODEL
GUIDANCE AGAIN IN GOOD AGREEMENT. FRONT ASSOCIATED WITH LEADING
EDGE OF WESTERLIES TO MOVE INTO STATE ON TUES SO BUMPED POPS TO
LIKELY. AS MODEL GUIDANCE STARTS TO HONE IN ON SPECIFICS AND WITH
LESS WEIGHT ON CLIMATOLOGY...BEGINNING TO APPEAR THAT TUES/WED
WILL BE SIGNIFICANTLY DRIER AND MODERATELY COOLER THAN NORMAL
AFTER FROPA. WED MAX TEMPS MAY REMAIN IN THE 70S IN HIGHER
ELEVATIONS OF NORTH GA. DEWPOINTS SHOULD BE IN THE 50S. AS FRONT
WASHES OUT AND LIFTS NORTH THURS/FRI WILL LIKELY SEE RETURN TO SCT
DIURNAL SHOWERS AND THUNDERSTORMS. USED DYNAMIC BLEND FOR FORECAST
TEMPS WHICH WEIGHTS RAW MODELS AND UNCORRECTED MOS GUIDANCE IN AREAS
OF RAIN AND CLOUDS AND BIAS CORRECTED MOS GUIDANCE IN AREAS OF NO
RAIN AND LESS CLOUDS.
SNELSON
&&
.AVIATION...
12Z UPDATE...
PATCHY LOW CIGS AND FOG SKIRTING THE AIRFIELD THIS MORNING. HAVE
ADDED A TEMPO GROUP FOR IFR CIGS FOR THE NEXT TWO HOURS. DIURNAL
CU EXPECTED AFTER THE FOG/HAZE AND LOW CLOUDS BURN OFF. HRRR STILL
KEEPS THE CHANCES FOR CONVECTION LOW AT ATL...SO WILL CONTINUE
WITH NO MENTION FOR NOW.
//ATL CONFIDENCE...12Z UPDATE...
LOW-MED CONFIDENCE ON CIGS FOR THE NEXT 2-4 HOURS.
OTHERWISE...HIGH CONFIDENCE REMAINING ELEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 91 71 93 70 / 30 30 20 10
ATLANTA 90 73 92 73 / 20 20 20 10
BLAIRSVILLE 85 66 86 63 / 30 30 30 10
CARTERSVILLE 91 71 93 69 / 20 20 20 10
COLUMBUS 92 74 94 73 / 30 30 20 10
GAINESVILLE 88 70 91 72 / 30 30 20 10
MACON 91 72 93 69 / 30 30 20 10
ROME 92 72 93 70 / 20 20 20 10
PEACHTREE CITY 90 71 92 69 / 20 20 20 10
VIDALIA 89 73 93 72 / 30 30 30 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1030 AM EDT SAT JUL 12 2014
.SYNOPSIS...
OFFSHORE HIGH PRESSURE WILL DOMINATE THE MID-ATLANTIC INTO SUNDAY.
A COLD FRONT WILL APPROACH THE AREA SUNDAY NIGHT INTO
MONDAY...WITH A STRONGER COLD FRONT LIKELY CROSSING THE AREA LATE
TUESDAY. HIGH PRESSURE WILL BUILD ALONG THE EASTERN SEABOARD FOR
THE SECOND HALF OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 14Z...SFC HIGH PRESSURE AXIS IS ALONG THE MID-ATLANTIC AND
SRN NEW ENGLAND COAST. MID-LEVEL CLOUDS EAST OF THE I-95 CORRIDOR
WILL CONTINUE TO DRIFT EAST FROM THE AREA THROUGH MIDDAY.
UPDATED POP/WX FORECAST BASED ON 11Z HRRR WITH A FARTHER EAST
FOCUS OF AFTERNOON SHOWER AND THUNDERSTORM ACTIVITY. CONVECTIVE
STORMS SHOULD INITIATE NEAR THE BLUE RIDGE AND PROGRESS OVER AT
LEAST THE WESTERN BALT-WASH SUBURBS. THIS WILL CONTINUE TO
MONITORED.
CONVECTION SHOULD BE DIURNALLY-DRIVEN AND DISSIPATE WITH THE SETTING
OF THE SUN. PATCHY FOG MAY FORM AGAIN OVERNIGHT...PARTICULARLY IN
CLIMATOLOGICALLY FOG PRONE AREAS AND ALSO PLACES THAT RECEIVE
RAINFALL.
&&
.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
MODELS HAVE BEEN CONSISTENT THAT MOISTURE AND INSTABILITY WILL
INCREASE FOR SUNDAY. GFS HAS PRECIPITABLE WATER VALUES INCREASING
CLOSE TO 2 INCHES BY DAY/S END...WITH DEWPOINTS NEAR 70 DEGREES.
MODELS ALSO SHOW A DECENT VORT MAX AFFECTING THE CWA...PROMOTING AT
LEAST SCATTERED SHOWERS AND THUNDERSTORMS. WHILE SHEAR STILL LOOKS
BEST NORTHWEST OF THE CWA...INSTABILITY AND STRENGTH OF VORT MAX MAY
PROMOTE A FEW STRONG OR SEVERE STORMS DURING THE AFTERNOON.
ACTIVITY FROM SUNDAY AFTERNOON SHOULD DIMINISH/MOVE AWAY SUNDAY
EVENING BUT WILL CONTINUE WITH LOW POPS ACROSS NORTHWEST PORTION OF
THE CWA AS FASTER ADVANCE OF A TROUGH/COLD FRONT MAY ALLOW FOR SOME
OVERNIGHT CONVECTION WITHIN THIS ZONE.
LEANED CLOSER TO MAV FOR MAXIMA SUNDAY GIVEN SOUTHWEST FLOW IN THE
LOW LEVELS...MAV/MET WERE SIMILAR FOR SUNDAY NIGHT.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
FCST FOR THE BGNG OF THE WK WL BE DOMINATED BY AN INCRSGLY AMPLIFIED
H5 PTTN...WHERE S/WV ENERGY WL DIVE ACRS THE GRTLKS...PUSHING A WELL
DEFINED CDFNT TWD THE ERN SEABOARD. AS CAN BE XPCTD W/ ANY ANOMALOUS
SOLN...VARIANCES EXIST AMONGST GDNC MEMBERS. REGARDLESS OF SPECIFICS
THERE IS CONSENSUS THAT CWFA MON WL BE W/IN WM SECTOR... AFFECTED BY
A HOT/HUMID/UNSTBL AMS. A LEE TROF AXIS MAY PROVIDE A NCSRY FOCUSING
MECHANISM...ALTHO ANOTHER SOURCE OF UVV WUD RESIDE ACRS THE NWRN CWFA
DUE TO APPROACHING BULK SHEAR AND OROGRAPHIC LIFT. HV OPTED TO PLACE
FOCUS...BY WAY OF LIKELY POPS...THERE. XPCT UPDRAFTS TO BE VIGOROUS
ENUF TO SUSTAIN THEMSELVES...AND HV CARRIED LKLY POPS INTO THE I-95
CRRDR BY EVNG. ALL NCSRY INGREDIENTS AVBL FOR TSTMS TO NOT ONLY
BECOME SVR...BUT ALSO BE ORGANIZED. JUST NEED TO SEE HOW IT ALL
SHAKES OUT.
AM THINKING THAT THE GFS MAY BE A LTL TOO QUICK W/ PROGRESSION OF
CDFNT. ITS TIMING WL ULTIMATELY DETERMINE THE FATE FOR TUE. A FASTER
FNT WUD CURTAIN SVR TSTM CHCS. TOO MANY DEBRIS CLDS WUD YIELD THE
SAME OUTCOME. EITHER WAY...THE I-95 CRRDR STANDS THE BEST CHC AT
RECEIVING MEASUREABLE PCPN...WHICH WARRANTS LKLY POPS TUE. TO THE
W...POPS HELD BACK AT CHC LVLS. SVR TSTM RISK FOR BOTH MON AND TUE
WL BE CONT TO BE CARRIED IN THE HWO.
MAXT MON SIMLR TO PRVS FCST...GOING A PINCH ABV GDNC TO ACCT FOR
WARM H8 TEMPS AND AMPLE INSOLATION. TUE MAXT NEARER CLIMO DUE TO
XPCTD CLDS. IN FACT...W OF BLURDG A BIT BLO CLIMO. THIS FCST PD MAY
HV THE HIEST ERROR POTL IN THE XTNDD FCST. STAYED WARM FOR MIN-T MON
NGT...AS DEWPTS NEAR 70F WL INHIBIT SUBSTANTIVE COOLING.
BY TUE NGT-WED...CDFNT WL BE PUSHING AWAY FM CWFA...PERMITTING CNDN
HIPRES TO BLD. THIS HIGH WL BE THE CONTROLLING WX INFLUENCE FOR THE
REST OF THE WK. TEMPS/DEWPTS WL BE REFRESHING FOR JULY IN THE MID
ATLC.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
A FEW THUNDERSTORMS MAY FORM NEAR THE HIGHER TERRAIN THIS
AFTERNOON...MRB/CHO MOST VULNERABLE. SOME GUIDANCE SUGGESTS THERE
COULD BE CONVECTION MOVING EAST TO AFFECT IAD LATER IN THE
AFTERNOON. CONFIDENCE LOW...AND HAVE RESTRICTED CHANCES ALONG/WEST
OF THE BLUE RIDGE.
IF SKIES CLEAR OUT TONIGHT...SOME FOG IS POSSIBLE ESPECIALLY
CHO/MRB. HIGHER COVERAGE OF THUNDERSTORMS IS EXPECTED SUNDAY WITH
BETTER MOISTURE/INSTABILITY AND A SHORTWAVE. AFTERNOON THUNDERSTORMS
WILL BE POSSIBLE ALL TERMINALS.
FLGT RESTRICTIONS LKLY AT TIMES MON-TUE INVOF TSRA. VFR WL PREVAIL
FOR A MAJORITY OF THE TIME...BUT BRIEF PDS AOB IFR PSBL.
HIPRES BLDS WED. VFR.
&&
.MARINE...
SLY FLOW 5-10 KT THIS MORNING WILL INCREASE THROUGH THIS
AFTERNOON INTO TONIGHT AS HIGH PRESSURE PUSHES EAST FROM THE AREA.
SCA IS EFFECT FOR THE MAIN OF THE CHESAPEAKE BAY AND INTO THE
LOWER TIDAL POTOMAC LATE TODAY INTO TONIGHT. THERE MAY BE A LULL
DURING THE DAY SUNDAY...BUT IT/S POSSIBLE WINDS INCREASE INTO SCA
CRITERIA AGAIN SUNDAY EVENING OR SUNDAY NIGHT.
INTERVALS OF TSRA LKLY MON-TUE...EACH POSING A GUSTY WIND THREAT.
GRADIENT FLOW MAY BE ENUF TO PLACE WATERS ON THE CUSP OF SCA
ANYWAYS. ANY ADDTL WIND WUD NECESSITATE SMW/S. THE FINAL WAVE WUD BE
A CDFNT. ATTM GDNC NOT SUGGESTING GUSTY WNDS IN NW FLOW
POST-FROPA...BUT BASED ON TEMP CONTRAST...SUSPECT THAT WL CHG.
THERE/S A BIT OF UNCERTAINTY ON EXACTLY WHEN CFP WUD BE. SINCE THATS
AT THE END OF THE MARINE PD...WL OMIT ATTM. LATER FCSTS CAN ADDRESS
THESE DETAILS.
&&
.TIDES/COASTAL FLOODING...
WATER LEVELS ARE A COUPLE TENTHS FOOT ABOVE THE ASTRONOMICAL
PREDICTION THIS MORNING. THIS ANOMALY WILL INCREASE AS SOUTHERLY
FLOW STRENGTHENS INTO TONIGHT. THIS INCREASE AND A FULL MOON SOON
WILL ALLOW WATER LEVELS TO APPROACH MINOR FLOODING THRESHOLDS
AT SENSITIVE SITES LIKE ANNAPOLIS DURING THE PREFERRED SUNDAY
MORNING HIGH TIDE.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 AM EDT SUNDAY
FOR ANZ531-539>541.
SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EDT
SUNDAY FOR ANZ532>534-537-543.
&&
$$
SYNOPSIS...BAJ/HTS
NEAR TERM...BAJ/BPP
SHORT TERM...BPP
LONG TERM...HTS
AVIATION...BAJ/BPP/HTS
MARINE...BAJ/BPP/HTS
TIDES/COASTAL FLOODING...BAJ
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1121 AM EDT SAT JUL 12 2014
.UPDATE...
CLEANED UP THE GRIDS THIS MORNING TO ACCOUNT FOR LACK OF SKY
FRACTION EARLY. PUSHED A MORE OPTIMISTIC FORECAST INTO THE
AFTERNOON...ALTHOUGH HIGH CLOUD IS CLOSING IN FAST. OFF OF THE
WARM START...INCREASED MAXIMUM TEMPERATURES A DEGREE OR TWO.
RECENT HIRES..CONVECTION ALLOWING MODELS INCLUDING ITERATIONS OF
THE HRRR AND MEMBERS OF THE IN-HOUSE HI-RESOLUTION WRF ENSEMBLE
ARE PORTRAYING HIGH CERTAINTY THAT PRECIPITATION AND SHOWER/TSTORM
ACTIVITY WILL REMAIN WELL WEST OF THE CWA THROUGHOUT THE MAJORITY
OF THE AFTERNOON...THROUGH 6PM. BULLISH NAM IS REALLY ON AN ISLAND
WITH REGARDS TO BRINGING QPF INTO THE AREA BEFORE 00Z. FORECASTED
CAPE FROM PLAN VIEW IMAGES SHOW MODEST INSTABILITY BECOMING
BOTTLED UP THIS AFTERNOON ACROSS FAR WESTERN PORTIONS OF LOWER
PENINSULA CENTERED ALONG A WEAK LEE OF LAKE MICHIGAN SURFACE
TROUGH. CONTINUED ANTICYCLONIC CURVATURE SUPPORTS A SHORTWAVE
RIDGING FEATURE AMPLIFYING DOWNSTREAM OF THE INBOUND BULLDOZER
TROUGH WHICH WILL ACTUALLY SUPPORT SUBSIDENCE OR SYNOPTIC SCALE
DESCENT. SHORTWAVE ENERGY WILL ARRIVE AND PASS OVER THE AREA BETWEEN
6-8PM...WHICH WILL BE COLLOCATED WITH AN INCREASE IN TANGIBLE
LOWER TROPOSPHERIC HUMIDITY AND ENTRY LEVEL CAPE. IT IS ALONG THIS
LEAD EDGE AND THE RICH THETAE ADVECTION BURST THAT SHOWERS AND A
POSSIBLE THUNDERSTORM COULD ARRIVE FOR THE EARLY EVENING.
OTHERWISE...EXPECTING MUCH OF THIS TO STRUGGLE. NO STRONG OR
SEVERE WEATHER EXPECTED THROUGH THIS EVENING.
STILL EXPECTING THE CATEGORICAL PRECIPITATION CHANCES TO INCREASE
LATE TONIGHT...POSSIBLY AS LATE AS 8 OR 9Z. THIS WILL OCCUR IN
COMBINATION OF UPPER LEVEL FLOW BECOMING CYCLONIC IN TIME DUE TO
THE ARRIVAL OF THE INBOUND DIGGING CLOSED LOW AS WELL AS
UPSTREAM CONVECTION/FRESH LOW LEVEL JET RESPONSE SLIDING OVER FAR
SOUTHERN LOWER MICHIGAN. WILL INVESTIGATE THIS FOR THE AFTERNOON
PACKAGE.
&&
.AVIATION...ISSUED 658 AM EDT SAT JUL 12 2014
//DISCUSSION...
VFR CONDITIONS WILL PERSIST THROUGH TODAY WITH A SLIGHT UPTICK IN
WINDS THIS AFTERNOON OUT OF THE SOUTHWEST. CLOUDS WILL INCREASE IN
COVERAGE AS DIURNAL HEATING IGNITES A CU FIELD AND DEBRIS FROM
UPSTREAM CONVECTION STREAMS INTO THE AREA. THERE IS A POSSIBILITY
FOR A FEW THUNDERSTORMS TO DEVELOP LATE THIS AFTERNOON AND EVENING
BUT COVERAGE SHOULD BE QUITE SPARSE SO WILL KEEP OUT OF THE TAFS AT
THE MOMENT. BEST CHANCE FOR WIDESPREAD THUNDERSTORM ACTIVITY WILL
COME OVERNIGHT AS A COMPLEX WORKS EASTWARD ACROSS LOWER MI. AT THIS
POINT IT LOOKS LIKE THE BEST TIMING WILL BE BETWEEN 06-12Z.
//DTW THRESHOLD THREATS...
* THERE IS MEDIUM CONFIDENCE THAT THUNDERSTORMS WILL OCCUR OVERNIGHT.
* THERE IS HIGH CONFIDENCE THAT CEILINGS WILL FALL BELOW 5000 FT
OVERNIGHT...BUT LOW CONFIDENCE ON EXACT TIMING.
&&
.PREV DISCUSSION...ISSUED 351 AM EDT SAT JUL 12 2014
SHORT TERM...TODAY AND TONIGHT
THE INTERACTION OF A STRONG MID/UPPER LEVEL TROUGH DIGGING INTO THE
GREAT LAKES AND A RESIDUAL STATIONARY BOUNDARY OVER THE OHIO VALLEY
EXTENDING WESTWARD TO THE MISSISSIPPI WILL MAKE FOR AN ACTIVE
STRETCH OF WEATHER THIS WEEKEND. ADDING TO THE COMPLEXITY WILL BE
SEVERAL SHORTWAVES EMBEDDED WITHIN BOTH FEATURES. AS THE SYSTEM GETS
DEEPER INTO THE HIRES RUNS WE CONTINUE TO GET A BETTER FEEL FOR
HOW THE EVENT LOOKS TO PLAY OUT. TODAY WILL BE A PERIOD OF
TRANSITION FROM THE DRY AND STABLE AIRMASS BROUGHT TO US BY THE
EXITING HIGH PRESSURE SYSTEM. THE INITIAL SURGE OF JET ENERGY
EXITING THE TROUGH WILL STAY TO THE NORTH OVER LAKE SUPERIOR AS IT
ROUNDS THE RIDGE STILL IN PLACE AS WE START THE DAY OFF. SEMBLANCE
OF A LOW AMPLITUDE SHORTWAVE RIDGE IN THE NEARLY ZONAL FLOW OVER THE
MIDWEST SHOULD ADD TO THE ALREADY STABLE/WARM MID LEVELS HELPING TO
KEEP THE AREA DRY. THE LEAD EDGE OF THE THETA E PLUME IS ENTERING
THE AREA AT PRESS TIME ON THE HEALS OF A SHORTWAVE SEEN ON WATER
VAPOR EXITING LAKE HURON. THIS WILL MERELY START THE SATURATION
PROCESS IN THE COLUMN WHICH HAD A PWAT OF ONLY 0.73 INCHES IN THE
00Z DTX SOUNDING FROM FRIDAY EVENING. MODEL SOUNDINGS SHOW THIS
JUMPING TO ABOVE 1.3 INCHES BY 12Z THIS MORNING AND CLOSE TO 1.8
INCHES BY THIS EVENING.
A STRONGER SHORTWAVE EMBEDDED IN THE SOUTHERN STREAM OF THE JET WILL
UNDERGO CYCLOGENESIS AS IT TRACKS ALONG THE AFOREMENTIONED
STATIONARY BOUNDARY TARGETING SE MI AROUND 00Z THIS EVENING. THIS
WILL REALLY ENHANCE THE MOISTURE FLUX INTO SOUTHERN MI WITH DEEP
LAYER OF SW FLOW DEVELOPING AHEAD OF THIS LOW. THE LOW WILL REACH US
CO-LOCATED WITH UPPER LEVEL DIFFLUENCE ALOFT...RIGHT ENTRANCE REGION
OF THE JET STREAK...NOCTURNAL LL JET AND THE STRONGEST INSTABILITY
GRADIENT. THIS SHOULD YIELD THUNDERSTORMS OVER MOST OF THE AREA
OVERNIGHT. BEST TIME FOR STORMS LOOKS TO BE AROUND 06-12Z TONIGHT. A
FEW SHOWERS/THUNDERSTORMS MAY POP UP AS EARLY AS 21Z MAINLY ACROSS
THE WESTERN COUNTIES AS INSTABILITY AND MOISTURE BEGIN TO SPILL INTO
THE AREA ON THE LEADING EDGE OF THE WEAKER THETA E GRADIENT. WE
COULD ALSO SEE SOME ACTION ACROSS THE FAR SOUTH AS THE COMPLEX SET
TO DEVELOP ON TONIGHTS LL JET WORKS ALONG THE STATIONARY FRONT. THE
TREND FOR THESE STORMS SHOULD BE TO WEAKEN AND FADE OUT AS THEY LOSE
THE BATTLE TO STABLE AIR BUT COULD CLIP THE AREA.
SPC HAS THE SLIGHT RISK AREA TO OUR WEST BUT DOES COVER A PORTION OF
SW LOWER MI. THIS SEEMS FAIR WITH THE TREND IN THE MODELS TO KEEP
THE LL JET FROM ENTERING SE MI TIL POTENTIALLY 09Z. WILL MONITOR
TRENDS IN TIMING THE MAIN FEATURE AND HOW WELL DEVELOPED THE SYSTEM
GETS TONIGHT. CURRENTLY THINKING IS THAT FEW STRONG STORMS COULD
DEVELOP WITH A WIND AND HAIL THREAT OVERNIGHT...BUT HEAVY RAIN WILL
BE A BIGGER THREAT WITH SUCH A MOIST AIRMASS ADVECTING IN.
LONG TERM...
SUNDAY GETS A BIT TRICKY AS THERE ARE VARYING MODEL SOLUTIONS WITH A
FAIRLY DRY GFS/ECMWF/GEM SOLUTION WHILE THE NAM HOLDS ON TO ABUNDANT
QPF. WHILE MODEL CONSENSUS BY ITSELF IS NOT ENOUGH TO THROW OUT THE
NAM...UPPER LEVEL FEATURES LEND CREDENCE TO THIS SOLUTION AS A
PRONOUNCED 700 MB DRY SLOT ADVECTS IN FROM THE WEST WHILE THE UPPER
LEVEL JET SINKS SOUTH...GIVING THE BEST MOISTURE AND DYNAMICS TO
AREAS ACROSS THE SOUTH AND EAST. THIS IS ALSO IN LINE WITH THE MOST
RECENT SPC DAY 2 OUTLOOK WHICH HAS PUSHED THE SLIGHT RISK JUST SOUTH
OF OUR CWA WHICH SEEMS REASONABLE GIVEN THE AFOREMENTIONED FACTORS.
THE DRY SLOT AND SOME SUNSHINE WILL ALLOW TEMPERATURES TO GET INTO
THE LOWER 80S ACROSS SOUTHEAST MICHIGAN SUNDAY AFTERNOON.
THIS DRY AIR BECOMES VERY PRONOUNCED SUNDAY NIGHT WITH THE LOSS OF
DAYTIME HEATING TAKING AWAY ANY BOOST FROM INCOMING SOLAR RADIATION.
POPS SUNDAY NIGHT WILL MAINLY BE CONFINED TO THE EVENING HOURS WITH
MAINLY DRY WEATHER EXPECTED LATER IN THE EVENING INTO THE OVERNIGHT
HOURS. THE DRIER COOLER AIR WILL ALLOW SOME RADIATIONAL
COOLING...PUSHING NIGHTTIME LOWS DOWN INTO THE UPPER 50S TO LOWER
60S.
AN UNSEASONABLY COLD AIRMASS WILL THEN INVADE THE GREAT LAKES REGION
FROM CANADA DURING THE UPCOMING WORK WEEK AS A DEEP TROUGH TAKES
CONTROL OF THE WEATHER. AS 850 MB TEMPERATURES TUMBLE WELL INTO THE
SINGLE DIGITS ABOVE ZERO...HIGH TEMPERATURES WILL BE LIMITED TO THE
MIDDLE TO UPPER 60S ON TUESDAY AS LOWS TUESDAY NIGHT FALL INTO THE
LOWER TO MIDDLE 50S TUESDAY NIGHT. THIS COLD AIR MASS COULD
CHALLENGE SOME RECORDS...ESPECIALLY WEDNESDAY WHEN THE RECORDS ARE
FAIRLY HIGH. WITHIN THE TROUGH PRECIPITATION CHANCES WILL
REMAIN...ALTHOUGH THE BEST CHANCES WILL BE DURING THE DAYTIME WHEN
DIURNAL HEATING PROVIDES A BOOST TO RAIN CHANCES. MODEST RIDGING
WILL PUSH DAYTIME HIGHS BACK INTO THE UPPER 70S BY FRIDAY...WHICH IS
STILL A GOOD 5 DEGREES BELOW NORMAL FOR THIS TIME OF YEAR.
MARINE...
LIGHT SOUTHERLY WINDS TODAY WILL BRING WARMER AND MORE HUMID
AIR INTO THE REGION BY LATE IN THE DAY. THE CHANCE FOR SHOWERS AND
THUNDERSTORMS WILL INCREASE OVER THE CENTRAL GREAT LAKES BY LATE
TODAY AND TONIGHT...CONTINUING INTO SUNDAY. AN UNSEASONABLY COOL
AIRMASS WILL TRACK INTO THE REGION DURING THE EARLY PART OF THE
WEEK...WITH GUSTY WEST WINDS EXPECTED ON TUESDAY. HOWEVER WINDS AND
WAVES ARE EXPECTED TO REMAIN BELOW HEADLINE CRITERIA.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.
&&
$$
UPDATE.......CB
AVIATION.....DRK
SHORT TERM...DRK
LONG TERM....KURIMSKI
MARINE.......KURIMSKI
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
748 AM EDT SAT JUL 12 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 313 AM EDT SAT JUL 12 2014
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE TODAY...BUT THE BULK OF
THEM SHOULD HOLD UNTIL LATE THIS AFTERNOON. THE SHOWERS AND STORMS
WILL THEN CONTINUE INTO TONIGHT...BEFORE DIMINISHING SUNDAY
MORNING. PERIODS OF HEAVY RAIN WILL BE POSSIBLE TONIGHT INTO EARLY
SUNDAY MORNING MAINLY ALONG AND SOUTH OF I-96. THERE IS ALSO THE
SLIGHT RISK FOR SEVERE STORMS TONIGHT...MAINLY SOUTHWEST OF GRAND
RAPIDS. WE WILL GRADUALLY DRY OUT SUNDAY AFTERNOON AND SUNDAY
NIGHT. THEN MORE SHOWERS AND A FEW THUNDERSTORMS WILL BE POSSIBLE
AGAIN ON MONDAY...MAINLY NORTH OF I-96. DAYTIME TEMPERATURES WILL
BE AROUND 80 TODAY AND SUNDAY...THEN COOL TO 70 TO 75 BY MONDAY.
THE SHOWERS ARE EXPECTED TO MOVE OUT OF THE AREA MONDAY NIGHT WITH
COOLER AIR FILTERING IN. HIGHS ON TUESDAY AND WEDNESDAY SHOULD ONLY
BE AROUND 70...BUT THEN WARM TO AROUND 80 FOR THURSDAY AND FRIDAY.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 313 AM EDT SAT JUL 12 2014
A COLD FRONT WAS JUST MOVING ACROSS THE MS RIVER EARLY THIS
MORNING...ALONG THE MN/WI BORDER. MAIN MOISTURE FLUX AND LIFT WILL
STILL REMAIN TO OUR WEST MUCH OF THE DAY. THEREFORE WILL LOWER POPS
AS THE MAIN FORCING DOES NOT ARRIVE UNTIL LATE AFTERNOON AND INTO
THIS EVENING. WILL CARRY CHANCE POPS THROUGH MID AFTERNOON...THEN
RAMP THEM UP TO LIKELY AFTER 5 PM AS THE FRONT REACHES EASTERN
WISCONSIN BY THE END OF THE DAY.
TONIGHT CONTINUES TO LOOKS QUITE WET...ESPECIALLY ALONG AND SOUTH OF
I-96 WHERE DEEP MOISTURE POOLS AHEAD OF THE FRONT AND PERSISTS THERE
THROUGHOUT THE NIGHT. PRECIPITABLE WATER VALUES CONTINUE TO BE NEAR
OR SLIGHTLY OVER 2 INCHES. THOUGHT ABOUT ISSUING A FLOOD WATCH...
BUT NOT SURE HOW WIDESPREAD THE HEAVY RAIN WILL BE OR IF WE WILL
JUST SEE POCKETS OF HEAVY RAINS. CONFIDENCE WAS NOT STRONG ENOUGH
AT THIS POINT.
THE RISK OF SEVERE STORMS APPEARS A BIT LESSEN NOW THAT THE LOW
LEVEL JET SEEMS TO ARRIVE AFTER 06Z...DURING AN INSTABILITY DOWNWARD
TREND BY THAT HOUR. CAN NOT RULE OUT THAT A STRONGER STORM OR TWO
MAY MOVE ACROSS THE LAKE AND IMPACT AREAS ALONG AND SOUTH OF I-96.
THE FRONT AND THE BULK OF THE PCPN SHOULD MOVE OUT SUNDAY MORNING.
THERE IS A SECONDARY SURFACE TROUGH THAT PASSES THROUGH DURING THE
AFTERNOON AND MAY PRODUCE A FEW SHOWERS AND STORMS...PARTICULARLY SE
OF GRR. THEN BY MONDAY AN UPPER LOW DROPS OVER THE U.P. THE
SOUTHERN CWA MAY BE DRY SLOTTED MUCH OF THE DAY...BUT WILL CARRY CHC
POPS ACROSS THE NORTH. AFTER HIGHS AROUND 80 TODAY AND SUNDAY...
TEMPS WILL COOL TO 70 TO 75 MONDAY.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 313 AM EDT SAT JUL 12 2014
AN UNUSUALLY CHILLY PERIOD OF WEATHER FOR MID JULY... IN SOUTHWEST
LOWER MICHIGAN... IS LOOKING MORE AND MORE LIKE WITH EACH MODEL RUN
THROUGH MOST OF THIS FORECAST TIME FRAME. EXPECT AFTERNOON
INSTABILITY SHOWERS AND ISOLATED THUNDERSTORMS... MOSTLY INLAND OF
US-131 TUESDAY AND WEDNESDAY. A FEW ISOLATED SHOWERS REMAIN POSSIBLE
THURSDAY AFTERNOON TOO. THEN DRY WEATHER WITH A SLOW WARM UP WILL
COMMENCE.
THE ECMWF CONTINUES TO BE PREFERRED TO THE GFS SINCE THE CONTINUITY
OF THE ECMWF REMAINS SUPERIOR TO THE GFS. THIS IS ESPECIALLY TRUE
IN THE MID LEVELS LIKE 700...500 AND 300 MB... THROUGH THIS FORECAST
PERIOD. THE ECMWF IS SLOWER TO EJECT THE UPPER LOW OVER THE GREAT
LAKES COMPARED TO THE GFS AND ECMWF CONTINUES TO BE SIGNIFICANTLY
FARTHER SOUTH WITH CENTER OF THE UPPER LEVEL LOW AS WELL. IT SHOULD
BE POINTED OUT THE CANADIAN GEM IS SIMILAR TO THE ECMWF IN TERMS OF
THE DEVELOPMENT AND MOVEMENT OF THE DEEP 500 MB LOW OVER LOWER
MICHIGAN TUESDAY INTO WEDNESDAY.
WITH THE COLD POOL OF AIR ASSOCIATED WITH THE UPPER LOW REMAINING IN
PLACE TUESDAY INTO WEDNESDAY...AND LOOKING AT MODEL SOUNDING IT SURE
LOOKS TO ME LIKE THERE WOULD BE SCATTERED SHOWERS AND THUNDERSTORMS
AROUND THE AREA. TYPICAL OF THIS SORT OF SET UP IN THE SUMMER
TIME... SMALL HAIL IS CLASSIC CHARACTERISTIC OF THIS SORT OF
SCENARIO. ECMWF MODEL SOUNDING WOULD ALSO SUPPORT THIS (INTO
WEDNESDAY EVENING). BEYOND THAT THE UPPER LOW SLOWER MOVES EAST OF
THE AREA AND BY THURSDAY AFTERNOON THE BACK EDGE OF THE UPPER LEVEL
JET IS OVER LAKE MICHIGAN (ECMWF). SO I KEEP THE CHANCE OF SHOWERS
GOING INTO THURSDAY AFTERNOON SINCE WE WOULD STILL HAVE ENOUGH COLD
AIR ALOFT TO SPARK CONVECTION. I DID TREND THE POP DOWN EACH
AFTERNOON AS THAT IS ALSO TYPICAL OF THIS SORT OF EVENT. WATER
SPOUTS MAY BE POSSIBLE GIVEN HOW COLD THE AIR WILL BE AT MID LEVELS.
TEMPERATURES WILL RUN WELL BELOW NORMAL... AS MUCH AS 10 TO 15
DEGREES BELOW NORMAL FOR TUE AND WEDNESDAY. IT WOULD NOT BE OUT OF
THE QUESTION AREAS EAST OF REED CITY ALONG ROUTE 10 COULD SEE SOME
PATCHY FROST WED NIGHT AND THURSDAY NIGHT. BY FRIDAY TEMPERATURES
WILL HAVE WARMED TO WITHING 5 DEGREES OF NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 746 AM EDT SAT JUL 12 2014
CURRENTLY ALL TAF SITES ARE VFR AND SHOULD REMAIN SO THROUGH MID
AFTERNOON. CONDITIONS SHOULD DETERIORATE EARLY TONIGHT AND I WOULD
EXPECT LARGELY IFR/MVFR CONDITIONS AFTER 06Z AT ALL TAF SITES.
BASED ON BOTH THE HRRR IN COMBINATION WITH NAMDNG5 IT SEEMS THE
BULK OF THE THUNDERSTORMS ACTIVITY WILL BE IN THE 03Z TO 09Z TIME
FRAME. WHILE A FEW SCATTERED SHOWERS/THUNDERSTORMS (HRRR) COULD
IMPACT THE TAF SITES BY LATE AFTERNOON... THE UPPER DYNAMICS IN
COMBINATION WITH THE LOW LEVEL JET SUGGEST THE BULK OF THE STORM
ACTIVITY WILL BE AFTER 03Z SO ALL THE TAFS WERE WRITING TO SHOW
THE THUNDERSTORM ACTIVITY MOSTLY IN THAT TIME RANGE. SEEMS THESE
WILL BE TRAINING STORMS SO ONCE OVER THE TAF SITES THEY SHOULD NOT
BE QUICK TO LEAVE. IT IS AT THAT TIME THE CEILINGS/VSBY WILL
LIKELY GO MVFR/IFR. THE LOW CEILING/VSBY SHOULD CONTINUE THROUGH
12Z SUNDAY EVEN IF THE RAIN HAS ENDED BY THEN.
&&
.MARINE...
ISSUED AT 313 AM EDT SAT JUL 12 2014
IT WILL BE ROUGHER ON THE LAKE THAN IT HAS BEEN OVER THE LAST COUPLE
OF DAYS. SOUTH WINDS WERE ALREADY REACHING AROUND 15 KNOTS EARLY
THIS MORNING AND THEY MAY REACH TO 20 KNOTS AT TIMES TODAY AS THE
PRESSURE GRADIENT TIGHTENS AHEAD OF COLD FRONT. IT CONTINUES TO
APPEAR WE WILL STAY BELOW SCA CRITERIA...BUT 2-4 FOOT WAVES WILL BE
LIKELY FROM HOLLAND NORTHWARD. THE SWIM HAZARD RISK WILL BE
MODERATE WITH LONGSHORE CURRENTS AND SOUTH FACING STRUCTURAL
CURRENTS POSSIBLE.
WITH THE COLD FRONT MOVING IN TONIGHT WINDS WILL GRADUALLY DIMINISH
AND WAVES SHOULD TREND DOWN AFTER NIGHTFALL. A WEST TO NORTHWEST
WIND WILL THEN PERSIST SUNDAY AND MONDAY...BUT SHOULD GENERALLY BE
15 KNOTS OR LESS.
&&
.HYDROLOGY...
ISSUED AT 249 PM EDT FRI JUL 11 2014
MAY NEED TO CONSIDER A FLOOD WATCH FOR SATURDAY AFTERNOON THROUGH
SUNDAY NIGHT. LOW LCLS...DEEP CAPE AND A DEEP WARM CLOUD LAYER
SUPPORT EFFICIENT RAINFALL PROCESS. LOCAL AMOUNTS WELL OVER 2 INCHES
POSSIBLE...ESPECIALLY IF THE STORMS TRAIN. CORFIDI DO BECOME SMALL
SAT NIGHT. THE OVERALL RISK WILL DEPEND ON HOW THE CONVECTION
UNFOLDS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...WDM
AVIATION...WDM
HYDROLOGY...MJS
MARINE...JK
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1011 AM CDT SAT JUL 12 2014
.UPDATE...
MORNING SURFACE ANALYSIS INDICATES THAT THE PREVIOUS STALLED
BOUNDARY IN THE AREA YESTERDAY HAS WASHED OUT AND FRONTAL ZONE IS
FURTHER TO THE N. 12Z MESOANALYSIS INDICATES 925MB MOISTURE GRADIENT
ORIENTED FROM NW TO SE ACROSS THE W/SW AND INTO SE MS. DUE TO WASHED
OUT FRONTAL ZONE...PWATS IN REGIONAL SOUNDINGS AROUND 1.6-1.8
INCHES...CURRENT MOISTURE GRADIENT AND THE HRRR INDICATING
SHOWER/THUNDERSTORM ACTIVITY SLIGHTLY FURTHER N...DECIDED TO MOVE
SLIGHT CHANCE POPS SLIGHTLY BACK TO THE N/NW NEAR THE I-20 CORRIDOR.
MOST GLOBAL MODELS...INCLUDING GFS/NAM...KEEP CONVECTION FURTHER S
WHILE THE EURO WANTS TO BRING SOME BACK INTO W MS/NE LA TODAY.
HOWEVER...STILL EXPECTING MOST COVERAGE TO BE FURTHER TO THE S/SE.
THERE COULD BE AN ISOLATED STRONG STORM TODAY IN THE S DUE TO VERTICAL
TOTALS AROUND 25-26 DEG. C. HEAVY DOWNPOURS ARE ALSO POSSIBLE DUE TO
LIGHT CORFIDI VECTORS/DEEP MOISTURE/SLOW STORM MOVEMENT. DEWPOINTS
SHOULD SLOWLY MIX OUT THIS AFTERNOON AND KEEP HEAT INDICES IN THE
97-101 DEGREE RANGE. HIGHS LOOK ON TRACK...WHICH IS SLIGHTLY COOLER
THAN MAV. COULD POTENTIALLY BE A TOUCH COOLER DUE TO TEMPS ALOFT IN
12Z KJAN SOUNDING BEING SIMILAR TO YESTERDAY BUT LITTLE CLOUDS OVER
MOST OF THE AREA AND SOME MIXING WILL LEAD TO A WARM AFTERNOON IN THE
LOW/MID 90S. REST OF THE FORECAST IS ON TRACK. /DC/
&&
.AVIATION...EXPECT MOSTLY VFR CONDITIONS AT ALL TAF SITES TODAY. AN
ISOLATED SHOWER/STORM IS POSSIBLE NEAR KHBG TODAY AND COULD BRING
VIS/CIG DOWN BRIEFLY TO MVFR. SOME MIST/PATCHY FOG IS
POSSIBLE...MAINLY IN SOUTHERN TAF SITES. /DC/SW/
&&
.PREV DISCUSSION... /ISSUED 400 AM CDT SAT JUL 12 2014/
SHORT TERM...TODAY THROUGH SUNDAY NIGHT...IT WILL BE A MUCH
DIFFERENT WEEKEND THIS WEEKEND THAN IT WAS THE LAST. 595DM UPPER
RIDGE WILL NOSE INTO OUR REGION...LEAVING MANY LOCATIONS DRY BUT
WARMER. THERE STILL REMAINS A SLIGHT CHANCE FOR SOME AFTERNOON
STORMS IN THE SOUTH WHERE HEIGHTS ARE NOT AS HIGH BUT THE REST OF
THE AREA SHOULD SEE LESS CONVECTION TODAY. HIGHS WILL REACH INTO THE
MID 90S ESPECIALLY IN THE DELTA AND NORTHERN AREAS WHERE A LITTLE
DRIER AIR MAY BE PRESENT THIS AFTERNOON.
UPPER RIDGING WILL BEGIN TO BREAK DOWN ON SUNDAY IN RESPONSE TO A
DEEPENING LARGE UPPER LOW COMING DOWN OUT OF CANADA. HIGHS ON SUNDAY
WILL STILL BE WARM IN THE 90S BUT THERE SHOULD BE A BETTER CHANCE
FOR CONVECTION IN THE SOUTH DURING THE AFTERNOON WHERE BETTER
MOISTURE WILL RESIDE. MAV GUIDANCE WAS STILL A TAD TOO WARM FOR
HIGHS SUNDAY SO LOWERED HIGHS ABOUT 1-2 DEGREES. HEAT INDICES WILL
ALSO BE HIGHER ON SUNDAY ESPECIALLY IN THE DELTA WHERE HEAT INDEX
READINGS COULD REACH INTO THE LOWER 100S. OVERNIGHT LOWS THROUGH THE
PERIOD WILL DROP INTO THE UPPER 60S/LOWER 70S WHICH WILL PRECLUDE
ANY NEED FOR ADVISORIES. /28/
LONG TERM...MONDAY THROUGH SATURDAY...CONTINUED WARM MONDAY AS
SITES TOP OUT 92-95F BUT A COOLER AND WETTER WEATHER PATTERN IS
EXPECTED FOR THE LONG TERM. COME MONDAY A CLOSED LOW WILL BE
DROPPING OVER THE GREAT LAKES REGION AND HELP DEEPEN AN UPPER LEVEL
TROUGH OVER THE NORTHEAST HALF OF THE CONUS. THE RESULTING LOWER
HEIGHTS OVER OUR REGION COMBINED WITH DEEP MOISTURE AND DAYTIME
HEATING WILL LEAD TO A GREATER COVERAGE OF MOSTLY AFTERNOON AND
EVENING SHOWERS AND THUNDERSTORMS. LOW TO MID 70 DEW POINTS AND PWS
BETWEEN 1.75-2.0 INCHES WILL BE BACK ACROSS OUR CWA. THERE ARE
TIMING AND STRENGTH DIFFERENCES IN THE MODELS WITH THIS NEXT SYSTEM
BUT CONSENSUS DROPS AN ASSOCIATED COLD FRONT INTO THE NORTHERN
PORTIONS OF OUR CWA BY TUESDAY MORNING. A FEW STRONG THUNDERSTORMS
WITH LOCALLY HEAVY RAIN THAT HAVE DEVELOPED ALONG AND AHEAD OF THE
FRONT OVERNIGHT MAY DROP INTO OUR HIGHWAY 82 CORRIDOR PRIOR TO
DAYBREAK TUESDAY MORNING. MODELS DIFFER ON HOW FAR SOUTH THE COLD
FRONT WILL DROP BEFORE IT STALLS. THE GFS IS FASTER IN SHIFTING THE
CLOSED LOW TO THE NORTHEAST AND STALLS THE COLD FRONT ACROSS THE
MIDDLE OF THE CWA WEDNESDAY. THE ECMWF AND CANADIAN ARE SLOWER IN
LIFTING THE CLOSED LOW OUT AND DRIVE THE COLD FRONT SOUTH OF OUR CWA
WEDNESDAY. THIS WOULD RESULT IN A COOLER AND DRIER FORECAST THAN THE
GFS WOULD SUGGEST FOR WEDNESDAY AND THURSDAY. WITH THE BOUNDARY
STALLED ACROSS OUR CWA AND NORTHWEST FLOW ALOFT ACROSS OUR REGION
MODELS SUGGEST THE POTENTIAL FOR AN MCS WEDNESDAY AND THURSDAY
NIGHTS. WITH PWS POOLING ABOVE TWO INCHES ALONG AND AHEAD OF THE
FRONT HEAVY RAIN POTENTIAL WILL EXIST THROUGH THE PERIOD AT LEAST
ACROSS THE SOUTHERN HALF OF OUR AREA AND WILL DEPEND ON THE LOCATION
OF THE STALLED FRONT. WEAK UPPER LEVEL TROUGHING LOOKS TO REMAIN
OVER OUR REGION FRIDAY INTO SATURDAY MAINTAINING DECENT RAIN CHANCES
AND COOLER THAN NORMAL TEMPERATURES THROUGH THE LONG TERM. /22/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 95 71 95 72 / 9 7 9 7
MERIDIAN 94 69 95 70 / 9 5 8 7
VICKSBURG 94 70 95 71 / 11 8 7 7
HATTIESBURG 94 71 95 72 / 22 10 32 10
NATCHEZ 92 70 93 72 / 18 8 23 10
GREENVILLE 95 71 96 74 / 5 5 7 10
GREENWOOD 95 69 95 73 / 5 4 8 10
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
DC/SW/28/22
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
624 AM CDT Sat Jul 12 2014
.UPDATE...
Issued at 507 AM CDT SAT JUL 12 2014
Moisture transport across northern and central Missouri has proven
sufficient this morning to generate some scattered showers in areas
north and east of Kansas City. This activity is not expected to
persist into the morning much past sunrise, but may bring a quick
shower with a few hundredths of an inch of rain. Still expecting
morning activity to dissipate in time to allow plenty of time for
sunny skies to help make it a hot and humid day across the region.
&&
.DISCUSSION...
Issued at 351 AM CDT SAT JUL 12 2014
Overnight convection remains mostly located in areas from northeast
Nebraska arching through central Iowa into Illinois, which coincides
with edge of the nocturnal jet where warm air and moisture transport
is piling up early this morning. Closer to home, starting to get
some scattered radar returns across central Missouri likely owing to
weak moisture transport noted from the SPCs meso-analysis page.
Early morning showers in central Missouri don`t look like they will
last long. HRRR and other meso-models advertising this modest
activity all have it dissipating as quickly as it appeared as the
primary focus for moisture transport will remain to our north along
the southern edge of the prevailing westerlies across Nebraska and
Iowa today. Convection to our north will likely reinforce a weak
cold front settling south into Kansas and Missouri late tonight,
which will eventually bring the focus for some rain farther south
--likely after midnight--. However, before that occurs we will have
to get through a hot and muggy day. H8 temperatures today in the 20C
to 22C range, along with plenty of insolation thanks to clearing
skies, should allow temperates to reach into the 90s across the
entire forecast region today.
For tonight...have bumped POPs after midnight into the likely range
as models are consistent in settling the activity across Nebraska
and Iowa into at least northern Missouri as the front settles south.
Rainfall totals across far northern Missouri could be a bit high
owing to precipitable water values will be over 1.5 inches, though
the storms should be progressive enough with the fronts movement to
limit flooding issues. Otherwise, severe potential can not be ruled
out, but shear looks highly confined to the front and late night
instability is not looking overly favorable. That said, small hail,
locally gusty winds and torrential rain would be the hazards to
highlight with any of our late Saturday Night/early Sunday Morning
activity.
Storm chances will linger into Sunday, but the next best chance for
storms looks to hold off till Monday as a shortwave trough rotates
through the northern Plains into the Great Lakes. This will push a
more substantial cold front into Missouri providing focus for more
storms.
Otherwise, still looking at the potential for record low maximum
temperatures for Tuesday and record low temperatures both Tuesday
and Wednesday as cool Canadian air settles south into the Plains
States.
&&
.AVIATION...(For the 12Z TAFS through 12Z Sunday Morning)
Issued at 624 AM CDT SAT JUL 12 2014
Early morning showers will remain north and east of the terminals this
morning, thus VFR conditions are expected through the rest of the
daylight and much of the overnight hours. A front settling south
tonight will bring thunderstorms with it. Confidence in the coverage
of the storms is still a bit iffy, and the timing is out towards the
end of this TAF cycle, but have included VCTS at the terminals, and
a TEMPO group at KSTJ, to highlight when storms may impact aviation.
Otherwise, expect breezy southerly winds to prevail during the
daylight hours.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
UPDATE...Cutter
DISCUSSION...Cutter
AVIATION...Cutter
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
507 AM CDT Sat Jul 12 2014
.UPDATE...
Issued at 507 AM CDT SAT JUL 12 2014
Moisture transport across northern and central Missouri has proven
sufficient this morning to generate some scattered showers in areas
north and east of Kansas City. This activity is not expected to
persist into the morning much past sunrise, but may bring a quick
shower with a few hundredths of an inch of rain. Still expecting
morning activity to dissipate in time to allow plenty of time for
sunny skies to help make it a hot and humid day across the region.
&&
.DISCUSSION...
Issued at 351 AM CDT SAT JUL 12 2014
Overnight convection remains mostly located in areas from northeast
Nebraska arching through central Iowa into Illinois, which coincides
with edge of the nocturnal jet where warm air and moisture transport
is piling up early this morning. Closer to home, starting to get
some scattered radar returns across central Missouri likely owing to
weak moisture transport noted from the SPCs meso-analysis page.
Early morning showers in central Missouri don`t look like they will
last long. HRRR and other meso-models advertising this modest
activity all have it dissipating as quickly as it appeared as the
primary focus for moisture transport will remain to our north along
the southern edge of the prevailing westerlies across Nebraska and
Iowa today. Convection to our north will likely reinforce a weak
cold front settling south into Kansas and Missouri late tonight,
which will eventually bring the focus for some rain farther south
--likely after midnight--. However, before that occurs we will have
to get through a hot and muggy day. H8 temperatures today in the 20C
to 22C range, along with plenty of insolation thanks to clearing
skies, should allow temperates to reach into the 90s across the
entire forecast region today.
For tonight...have bumped POPs after midnight into the likely range
as models are consistent in settling the activity across Nebraska
and Iowa into at least northern Missouri as the front settles south.
Rainfall totals across far northern Missouri could be a bit high
owing to precipitable water values will be over 1.5 inches, though
the storms should be progressive enough with the fronts movement to
limit flooding issues. Otherwise, severe potential can not be ruled
out, but shear looks highly confined to the front and late night
instability is not looking overly favorable. That said, small hail,
locally gusty winds and torrential rain would be the hazards to
highlight with any of our late Saturday Night/early Sunday Morning
activity.
Storm chances will linger into Sunday, but the next best chance for
storms looks to hold off till Monday as a shortwave trough rotates
through the northern Plains into the Great Lakes. This will push a
more substantial cold front into Missouri providing focus for more
storms.
Otherwise, still looking at the potential for record low maximum
temperatures for Tuesday and record low temperatures both Tuesday
and Wednesday as cool Canadian air settles south into the Plains
States.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday Night)
Issued at 1212 AM CDT SAT JUL 12 2014
Little change in this forecast from the previous forecast. Inserted
an ending time for the wind gusts Saturday evening. A cold front will
sag southward through the evening/overnight hours on Saturday night.
Expect the convective activity to remain north of the terminals until
the very end of the forecast period, but thunderstorms should be
moving into KSTJ and KMCI/KMKC shortly after 06z.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
UPDATE...Cutter
DISCUSSION...Cutter
AVIATION...Leighton
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
628 AM CDT SAT JUL 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM CDT SAT JUL 12 2014
THE MODELS BRING ANOTHER DISTURBANCE THROUGH THE FCST AREA THIS
AFTERNOON. THERE ARE DIFFERENCES IN THE FOCUS FOR THUNDERSTORM
DEVELOPMENT. THE ECM FAVORS THE HIGH PLAINS AND SWRN NEB WHILE
THE NAM AND GEM SOLNS FAVOR NRN NEB. THE FORECAST FOLLOWS A BLEND
OF THESE SOLNS FOR ISOLATED TO SCATTERED POPS. NONE OF THE MODELS
SHOW HEAVY RAIN DEVELOPING BUT GIVEN THE WEAK FOCUS THIS MIGHT BE
NORMAL.
THE RAP SUGGESTS NO SIGNIFICANT DECREASE IN MOISTURE...PWS OVER
1.5 INCHES...SO STORMS WHICH FORM SHOULD CONTINUE TO PRODUCE
LOCALLY HEAVY RAINFALL.
LIGHT NORTH WINDS DEVELOP TODAY WITH LOW PRESSURE SOUTH OF THE
FCST AREA. THIS SHOULD LIMIT HIGHS TO THE 70S TO MID 80S. TONIGHT
LOWS FALL INTO THE 50S TO LOWER 60S AS THE FIRST PUSH OF DRIER
COOLER AIR MOVES INTO THE FCST AREA.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 354 AM CDT SAT JUL 12 2014
A COLD FRONT WILL PUSH INTO THE REGION LATE SUNDAY. AHEAD OF THE
FRONT PARTLY CLOUDY TO MOSTLY SUNNY SKIES SHOULD HELP TO WARM
TEMPS INTO THE 80S. ELEVATED INSTABILITY IS MARGINAL AND NOT
LOOKING AS GOOD AS YESTERDAY. PWATS DROP TO AROUND 1 INCH...WHICH
IS BELOW THE 50 PERCENTILE FOR JULY. EVEN THOUGH MOISTURE IS
LIMITED COOL AIR ALOFT WILL CREATE SOME STEEP LAPSE RATES. LOWERED
POPS FOR THE DAY...ALTHOUGH DID NOT ELIMINATE. MEANWHILE
UNSEASONABLY COLD UPPER LEVEL WILL BE DRIFTING ACROSS CENTRAL
CANADA TOWARDS THE GREAT LAKES.
THE COLD FRONT WILL MOVE ACROSS THE AREA SUNDAY NIGHT. SFC HIGH
PRESSURE WILL DEVELOP OVER THE DAKOTAS INTO NEB FOR MONDAY. BY
TUESDAY NIGHT INTO WEDNESDAY THE HIGH WILL DOMINATE MOST OF THE
PLAINS. TEMPS ASSOCIATED WITH THE HIGH WILL BE NOTICEABLY
COOLER...WITH HIGHS ONLY IN THE 70S...WITH MANY LOCATIONS HOLDING
IN THE LOWER 70S. MONSOON FLOW CONTINUES ALONG THE
SOUTHERN/CENTRAL ROCKIES. MODELS BRING SOME OF THIS MOISTURE INTO
SW NEB AND WILL CONTINUE LOW POPS.
COLD SNAP WILL BEGIN TO RELAX LATE WED AS THE UPPER LEVEL LOW WILL
LIFT INTO TO THE NORTHEAST. THE WESTERN RIDGE WILL THEN EXPAND
ACROSS THE ROCKIES. MODELS PUSH THE MONSOON MOISTURE SOUTH AS WARM
AIR EXPANDS ACROSS THE AREA. HIGHS SHOULD REBOUND BACK TO AROUND
80 FOR THURSDAY AND INTO THE 80S FOR FRIDAY. NUMERICAL MOS
GUIDANCE BRINGS TEMPS INTO THE 90S FOR FRIDAY ACROSS THE
WEST...HOWEVER THE WAY THIS SUMMER HAS GONE...HIGHS LIKELY IN THE
MID TO UPPER 80S. FLOW BECOMES NORTHWEST AND WILL HAVE TO MONITOR
DISTURBANCES FOR POSSIBLE ISOLATED ACTIVITY. FORECAST IS DRY AT
THIS TIME...BUT LOW POPS MAY BE NEEDED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 627 AM CDT SAT JUL 12 2014
TRAPPED MOISTURE IN THE PLATTE VALLEY IS PRODUCING IFR CIGS. THESE
SHOULD LIFT TO MVFR/VFR 14Z-16Z. OTHER IFR CIGS ACROSS KBBW-KONL
AREAS DEVELOPED FROM THE HEAVY RAINFALL LAST NIGHT. THESE ALSO
SHOULD LIFT SLOWLY TO MVFR/VFR 16Z-18Z. VFR IS EXPECTED ALL AREAS
THEREAFTER. ISOLATED TO SCATTERED TSTM COVERAGE DEVELOPS LATE THIS
AFTERNOON FROM WEST TO EAST. THIS ACTIVITY IS EXPECTED TO EXIT THE
FCST AREA 00Z-03Z FROM NORTH TO SOUTH.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1035 AM EDT SAT JUL 12 2014
.SYNOPSIS...
HIGH PRESSURE OVER THE EASTERN SEABOARD WILL BRING ANOTHER NICE
DAY TO CENTRAL NEW YORK AND NORTHEAST PENNSYLVANIA. A STORM
SYSTEM WILL APPROACH THE REGION FROM THE WEST LATE TONIGHT BRINGING
A CHANCE FOR SHOWERS AND THUNDERSTORMS. THE CHANCE FOR SHOWERS
AND THUNDERSTORMS WILL CONTINUE INTO TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
1030 AM UPDATE...12Z BUF RAOB AND LATEST RAP SOUNDINGS SHOW A
FAIRLY STRONG CAP AROUND 700 MB WHICH WILL INHIBIT CONVECTION THIS
AFTERNOON. WILL CONTINUE WITH DRY FORECAST FOR THIS AFTERNOON JUST
MINOR TWEAKS TO TEMPS OTHERWISE ALL GOOD.
PREVIOUS DISC...
HIGH PRESSURE SLIDING OFF THE EAST COAST WILL ALLOW
WARMER AND MORE HUMID AIR TO WORK INTO THE REGION TODAY. MDL
PROFILES DISPLAY ALOT OF VARIABILITY THIS AFTN W/RESPECT TO POTNL
FOR AFTN CONVECTION. 00Z BUF PROFILE SHOWS A GOOD CAP AT 700 MB
WHICH WOULD TEND TO INHIBIT ACTIVITY. LOW LVL MSTR APPEARS
OVERDONE IN THE NAM...WHILE THE RUC MAY BE DISPLAYING A DRY BIAS
W/RESPECT TO LOW LVL TD/S. GFS PROFILES APPEAR TO BE MOST
REASONABLE AND SUGGEST THE CAP WILL BE ENUF TO SUPPRESS CONVECTION
THIS AFTN. IN ADDN...FCST K`S ARE GNRLY IN THE U20S THIS AFTN.
WHILE A STRAY SHRA CAN`T BE RULED OUT LATE TDA...WE`VE OPTED TO
LOWER POPS TO BLO SLGT CHC. BETTER CHCS FOR CONVECTION WILL COME
TWDS DAYBREAK AS LEADING S/WV AHEAD OF THE DEEPENING GTLAKES UPR
LOW APRCHS THE RGN.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
XPCT SHRA/TSRA TO OVERSPREAD THE RGN SUN MRNG...THEN WORK THRU
DURING THE DAY. CAPES GNRLY IN THE 500-1000 RNG...WITH RATHER
IMPRSV WIND FIELDS. THIS WOULD SUGGEST A LOW END SVR THREAT FOR
MUCH OF THE RGN. AFTER THIS 1ST WAVE WORKS THRU...SOME DIFFS DVLP
IN THE GUIDANCE W/RESPECT TO TIMING AND DVLPMT AHEAD OF THE MAIN
UPR TROF AXIS. XPCT ANOTHER PUSH OF MSTR NWD AS NXT WAVE APRCHS. WE
KEPT HIGH CHC/LIKELY POPS FOR THESE PDS. THE FINGER LAKES...WRN
MOHAWK VLY AND SRN TUG COULD SEE A MAINLY DRY DAY ON MON BEFORE
THE NXT WAVES MOVS IN...SO ONLY INDICATE CHC POPS THERE WITH
HIGHER POPS FURTHER TO THE SOUTH.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
3 AM UPDATE...
NO CHGS TO LONG TERM GRIDS WITH THIS MORNING`S UPDATE. 00Z MODELS
CONTINUE TO SHOW SIGNIFICANT DISCREPANCIES WITH TIMING OF LOPRES
AND ASSOC FROPA WITH LATEST EURO NOT BRINGING CDFNT THRU AREA
UNTIL 12Z WED WHILE 00Z GFS BRINGS IT THRU BY 12Z TUE. UPR LVL
LOWS ARE NOTORIOUSLY HARD TO PREDICT AS THEY TEND TO MEANDER AS
THEY GET CUT OFF FM THE MAIN FLOW, THUS HV MADE NO CHGS TO EXTNDD
FOR THIS REASON.
PREV DISCUSSION BLO...
EXTENDED FORECAST PERIOD WILL BE DOMINATED BY A DEEP UPPER LEVEL
TROF THAT SETTLES OVER THE EASTERN UNITED STATES EARLY IN THE
PERIOD AND PERSISTS THROUGH LATE WEEK. AT THE SFC, A COLD FRONT
WILL TRACK ACROSS THE AREA MONDAY NIGHT INTO TUESDAY. THIS BOUNDARY
WILL BE ACCOMPANIED BY SHOWERS AND THUNDERSTORMS SOME OF WHICH MAY
BE STRONG TO SEVERE DEPENDING ON HOW UNSTABLE THE AIRMASS IS AT THE
TIME OF FROPA. THIS FAR OUT, MEDIUM RANGE MODELS CONTINUE TO SHOW
TIMING DIFFERENCES WITH FRONTAL PASSAGE THEREFORE THERE STILL
REMAINS MUCH UNCERTAINTY TO THE POTENTIAL FOR SEVERE WEATHER. WILL
CONTINUE TO ADVERTISE HIGH CHC/LOW LIKELY POPS MONDAY NIGHT AND
TUESDAY. AFTER SOME LINGERING SHOWERS TUESDAY NIGHT REST OF PERIOD
LOOKS DRY AND COOL WITH SFC HIGH PRES IN THE VCNTY. HIGH TEMPS WED
THROUGH FRIDAY WILL GENERALLY RANGE IN THE 70S.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
12Z UPDATE...
KELM HAS DROPPED DOWN TO MVFR VSBYS AND SHOULD REMAIN THERE
THROUGH 13Z, OTHER THAN THAT ALL TERMINALS SHOULD BE VFR FOR THE
NEXT 24 HOURS WITH THE POSSIBLE EXCEPTION OF AVP LATE IN THE
PERIOD. EXPECT ALL TERMINALS TO START OFF WITH A SCT MID-DECK ARND
7KFT AT 12Z WITH CUMULUS DEVELOPING BY 15Z WITH CLD HGTS STILL
REMAINING VFR AROUND 5KFT. CUMULUS EXPECTED TO DIMINISH BY 00Z
WITH JUST HIGH-LEVEL CIRRUS AHEAD OF NEXT WAVE LOWERING TO 10KFT
AT NY TERMINALS AFTER 09Z. AVP WILL BE LAST TO SEE BKN MID-DECK
ARRIVE IN, THUS HAVE GONE PREDOMINANT MVFR VSBYS AFTER 09Z AT THIS
TERMINAL. CONTINUE TO HAVE VERY LITTLE CONFIDENCE IN SHOWER
CHANCES TODAY AND WILL WITHHOLD FROM ANY TEMPO GROUPS UNTIL THEY
ACTUALLY DEVELOP.
WINDS LGT/VRB THIS MORNING WILL INCREASE TO BETWEEN 5-8 KTS OUT OF THE
SOUTHWEST BY MID-MORNING, DIMINISHING LATE IN THE DAY.
OUTLOOK...
SUN THROUGH TUE NGT...POTENTIAL RESTRICTIONS FROM SHRA/TSRA.
WED...PRIMARILY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...RRM
SHORT TERM...
LONG TERM...PVN/RRM
AVIATION...PVN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
638 AM EDT SAT JUL 12 2014
.SYNOPSIS...
HIGH PRESSURE OVER THE EASTERN SEABOARD WILL BRING ANOTHER NICE
DAY TO CENTRAL NEW YORK AND NORTHEAST PENNSYLVANIA. A STORM
SYSTEM WILL APPROACH THE REGION FROM THE WEST LATE TONIGHT BRINGING
A CHANCE FOR SHOWERS AND THUNDERSTORMS. THE CHANCE FOR SHOWERS
AND THUNDERSTORMS WILL CONTINUE INTO TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE SLIDING OFF THE EAST COAST WILL ALLOW WARMER AND
MORE HUMID AIR TO WORK INTO THE REGION TODAY. MDL PROFILES
DISPLAY ALOT OF VARIABILITY THIS AFTN W/RESPECT TO POTNL FOR AFTN
CONVECTION. 00Z BUF PROFILE SHOWS A GOOD CAP AT 700 MB WHICH WOULD
TEND TO INHIBIT ACTIVITY. LOW LVL MSTR APPEARS OVERDONE IN THE
NAM...WHILE THE RUC MAY BE DISPLAYING A DRY BIAS W/RESPECT TO LOW
LVL TD/S. GFS PROFILES APPEAR TO BE MOST REASONABLE AND SUGGEST
THE CAP WILL BE ENUF TO SUPPRESS CONVECTION THIS AFTN. IN
ADDN...FCST K`S ARE GNRLY IN THE U20S THIS AFTN. WHILE A STRAY
SHRA CAN`T BE RULED OUT LATE TDA...WE`VE OPTED TO LOWER POPS TO BLO
SLGT CHC. BETTER CHCS FOR CONVECTION WILL COME TWDS DAYBREAK AS
LEADING S/WV AHEAD OF THE DEEPENING GTLAKES UPR LOW APRCHS THE
RGN.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
XPCT SHRA/TSRA TO OVERSPREAD THE RGN SUN MRNG...THEN WORK THRU
DURING THE DAY. CAPES GNRLY IN THE 500-1000 RNG...WITH RATHER
IMPRSV WIND FIELDS. THIS WOULD SUGGEST A LOW END SVR THREAT FOR
MUCH OF THE RGN. AFTER THIS 1ST WAVE WORKS THRU...SOME DIFFS DVLP
IN THE GUIDANCE W/RESPECT TO TIMING AND DVLPMT AHEAD OF THE MAIN
UPR TROF AXIS. XPCT ANOTHER PUSH OF MSTR NWD AS NXT WAVE APRCHS. WE
KEPT HIGH CHC/LIKELY POPS FOR THESE PDS. THE FINGER LAKES...WRN
MOHAWK VLY AND SRN TUG COULD SEE A MAINLY DRY DAY ON MON BEFORE
THE NXT WAVES MOVS IN...SO ONLY INDICATE CHC POPS THERE WITH
HIGHER POPS FURTHER TO THE SOUTH.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
3 AM UPDATE...
NO CHGS TO LONG TERM GRIDS WITH THIS MORNING`S UPDATE. 00Z MODELS
CONTINUE TO SHOW SIGNIFICANT DISCREPANCIES WITH TIMING OF LOPRES
AND ASSOC FROPA WITH LATEST EURO NOT BRINGING CDFNT THRU AREA
UNTIL 12Z WED WHILE 00Z GFS BRINGS IT THRU BY 12Z TUE. UPR LVL
LOWS ARE NOTORIOUSLY HARD TO PREDICT AS THEY TEND TO MEANDER AS
THEY GET CUT OFF FM THE MAIN FLOW, THUS HV MADE NO CHGS TO EXTNDD
FOR THIS REASON.
PREV DISCUSSION BLO...
EXTENDED FORECAST PERIOD WILL BE DOMINATED BY A DEEP UPPER LEVEL
TROF THAT SETTLES OVER THE EASTERN UNITED STATES EARLY IN THE
PERIOD AND PERSISTS THROUGH LATE WEEK. AT THE SFC, A COLD FRONT
WILL TRACK ACROSS THE AREA MONDAY NIGHT INTO TUESDAY. THIS BOUNDARY
WILL BE ACCOMPANIED BY SHOWERS AND THUNDERSTORMS SOME OF WHICH MAY
BE STRONG TO SEVERE DEPENDING ON HOW UNSTABLE THE AIRMASS IS AT THE
TIME OF FROPA. THIS FAR OUT, MEDIUM RANGE MODELS CONTINUE TO SHOW
TIMING DIFFERENCES WITH FRONTAL PASSAGE THEREFORE THERE STILL
REMAINS MUCH UNCERTAINTY TO THE POTENTIAL FOR SEVERE WEATHER. WILL
CONTINUE TO ADVERTISE HIGH CHC/LOW LIKELY POPS MONDAY NIGHT AND
TUESDAY. AFTER SOME LINGERING SHOWERS TUESDAY NIGHT REST OF PERIOD
LOOKS DRY AND COOL WITH SFC HIGH PRES IN THE VCNTY. HIGH TEMPS WED
THROUGH FRIDAY WILL GENERALLY RANGE IN THE 70S.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
12Z UPDATE...
KELM HAS DROPPED DOWN TO MVFR VSBYS AND SHOULD REMAIN THERE
THROUGH 13Z, OTHER THAN THAT ALL TERMINALS SHOULD BE VFR FOR THE
NEXT 24 HOURS WITH THE POSSIBLE EXCEPTION OF AVP LATE IN THE
PERIOD. EXPECT ALL TERMINALS TO START OFF WITH A SCT MID-DECK ARND
7KFT AT 12Z WITH CUMULUS DEVELOPING BY 15Z WITH CLD HGTS STILL
REMAINING VFR AROUND 5KFT. CUMULUS EXPECTED TO DIMINISH BY 00Z
WITH JUST HIGH-LEVEL CIRRUS AHEAD OF NEXT WAVE LOWERING TO 10KFT
AT NY TERMINALS AFTER 09Z. AVP WILL BE LAST TO SEE BKN MID-DECK
ARRIVE IN, THUS HAVE GONE PREDOMINANT MVFR VSBYS AFTER 09Z AT THIS
TERMINAL. CONTINUE TO HAVE VERY LITTLE CONFIDENCE IN SHOWER
CHANCES TODAY AND WILL WITHHOLD FROM ANY TEMPO GROUPS UNTIL THEY
ACTUALLY DEVELOP.
WINDS LGT/VRB THIS MORNING WILL INCREASE TO BETWEEN 5-8 KTS OUT OF THE
SOUTHWEST BY MID-MORNING, DIMINISHING LATE IN THE DAY.
OUTLOOK...
SUN THROUGH TUE NGT...POTENTIAL RESTRICTIONS FROM SHRA/TSRA.
WED...PRIMARILY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...PVN/RRM
AVIATION...PVN
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
635 AM CDT SAT JUL 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 319 AM CDT SAT JUL 12 2014
MAIN SHORT TERM CONCERN IS ON PRECIPITATION TRENDS THROUGH THE
EVENING AS WELL AS SEVERE WEATHER POTENTIAL.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A SUBTROPICAL HIGH OVER THE CENTRAL PLAINS AND A DEEP UPPER
TROUGHING COVERING MUCH OF CENTRAL CANADA. A SERIES OF MONSOONAL
SHORTWAVES WERE COMING AROUND THE WEST SIDE OF THE SUBTROPICAL
HIGH...ONE OVER SOUTH CENTRAL SOUTH DAKOTA AND A SECOND IN WYOMING. A
STREAM OF TROPICAL PACIFIC MOISTURE WAS ALSO EVIDENT AROUND THE
SUBTROPICAL HIGH. IN THE LOWER LEVELS...A PLUME OF 15-18C 850MB
DEWPOINTS STRETCHED FROM OKLAHOMA INTO SOUTH DAKOTA AND SOUTHERN
MINNESOTA PER 00Z RAOBS. ALL THIS MOISTURE EQUATES TO PRECIPITABLE
WATER VALUES OF AROUND 2 INCHES FROM SIOUX FALLS AREA SOUTHEAST INTO
CENTRAL ILLINOIS. A ZONE OF 850MB MOISTURE TRANSPORT AHEAD OF THE
MONSOONAL SHORTWAVES ACTING ON THIS MOISTURE...ALONG WITH LOW TO MID
LEVEL FRONTOGENESIS...HAS LED TO SHOWERS AND STORMS IN THAT
PRECIPITABLE WATER MAXIMUM. THIS PRECIPITATION HAS CAUSED THE
MAIN SURFACE WARM FRONT TO GET STUCK IN FAR SOUTHERN IOWA.
SOME OF THE GENERALITIES FOR TODAYS FORECAST. THE 2 MONSOONAL
SHORTWAVES WILL TRACK ACROSS THE FORECAST AREA...HELPING TO PULL THE
850MB MOISTURE TRANSPORT ZONE AND LOW TO MID LEVEL FRONTOGENESIS
NORTHWARD TOWARDS AND POSSIBLY INTO THE AREA. IN ADDITION...AN UPPER
JET STREAK ASSOCIATED WITH THE CENTRAL CANADA UPPER TROUGH IS
PROGGED TO ALIGN ITSELF FROM CENTRAL MN THROUGH LAKE SUPERIOR...
PLACING SOME IF NOT ALL OF THE FORECAST AREA IN THE FAVORABLE RIGHT
ENTRANCE REGION. INSTABILITY WISE...ALONG AND SOUTH OF THE WARM
FRONTAL BOUNDARY 1500-2500 J/KG OF MLCAPE SEEMS REASONABLE TO
DEVELOP THIS AFTERNOON...AS TEMPS CLIMB INTO THE 80S AND DEWPOINTS
HOVER IN THE MID 70S OR SO. PLENTIFUL PRECIPITABLE WATER AROUND AS
WELL AS NOTED IN THE CURRENT WEATHER DISCUSSION...RUNNING AROUND 2
INCHES. THUS...PLENTY OF MOISTURE EXISTS TO COMBINE WITH DYNAMIC AND
THERMODYNAMIC FORCING TO PRODUCE CONVECTION. 0-6KM AND 0-3KM SHEAR
VALUES REMAIN FAVORABLE FOR ORGANIZED SEVERE CONVECTION...ON THE
ORDER OF 40-50 KT AND 30-45 KT RESPECTIVELY. MUCH OF THIS SHEAR IS
CONFINED ABOVE 1 KM AS THE WINDS BELOW ARE FAIRLY LIGHT. STILL HAVE
CYCLONIC CURVATURE IN THE HODOGRAPH...THOUGH. BASED ON THE
AFOREMENTIONED PARAMETERS...DAMAGING WINDS AND HEAVY RAINS WOULD BE
THE MAIN CONCERNS...WITH SOME MARGINALLY SEVERE HAIL AND AN OUTSIDE
CHANCE OF A TORNADO. THE HIGHER SHEAR AND DRYING SOILS AS OF LATE
SHOULD HELP TO KEEP ANY FLOOD CONCERN LOCALIZED...IN AGREEMENT TOO
WITH THE DAY 1 EXCESSIVE RAINFALL OUTLOOK.
NOW...THE CRITICAL UNCERTAINTIES...
1. TIMING AND INTENSITY OF THE 2 MONSOONAL SHORTWAVES...WHICH
IMPACTS THE MOVEMENT OF THE 850MB MOISTURE TRANSPORT ZONE AND LOW TO
MID LEVEL FRONTOGENESIS. WHERE THAT MOISTURE TRANSPORT NOSE...F-GEN
ZONE...AND DPVA FROM THE SHORTWAVES WILL MODULATE WHERE THE
CONVECTION ENDS UP. MODELS ARE ALL OVER THE BOARD WITH THESE
SHORTWAVES...LEADING TO LOWERED CONFIDENCE.
2. HOW FAR NORTH THE WARM FRONT CAN MAKE IT WHICH IMPACTS THE ZONE
OF INSTABILITY AND THUS HOW FAR NORTH THROUGH THE FORECAST AREA A
SEVERE RISK EXISTS. ITEM NUMBER 1 ABOVE WILL IMPACT THE WARM FRONT.
DESPITE THE UNCERTAINTIES ABOVE...IT STILL APPEARS THROUGH THIS
EVENING LOCATIONS SOUTH OF I-90 STAND TO SEE THE HIGHEST CHANCE FOR
CONVECTION. ADDITIONALLY...SEVERE WEATHER IS GOING TO HAPPEN BETWEEN
I-80 AND I-90 AFTER 2 PM TODAY...CONSISTING OF SUPERCELLS AND BOW
SEGMENTS. PINNING DOWN THE LOCATION ANY FINER THAN THAT IS
PROBLEMATIC AT THIS TIME. LATER FORECAST UPDATES SHOULD BE ABLE TO
REFINE THE LOCATION AND TIMING.
HAVE ADJUSTED THE MORNING PORTION OF THE FORECAST TO FOLLOW TRENDS
IN THE HRRR...WHILE A MODEL CONSENSUS DOMINATES THE AFTERNOON AND
EVENING. NOTE THAT THERE COULD ALSO BE SOME SURFACE BASED CONVECTION
THAT FIRES OVER WEST CENTRAL WI THIS AFTERNOON ALONG A SOUTHEASTWARD
MOVING COLD FRONT. THE AFOREMENTIONED CONSENSUS JUST HAPPENS TO BE
SIMILAR TO THE 00Z NSSL WRF-ARW. HEADING INTO TONIGHT...THERE WILL
BE A NORTHWEST TO SOUTHEAST DRYING TREND AS THE SHORTWAVES PUSH OFF
TO THE EAST... USHERING IN SUBSIDENCE AND MUCH DRIER PRECIPITABLE
WATER VALUES.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 319 AM CDT SAT JUL 12 2014
A GRADUAL DESCENT OF THE DEEP UPPER TROUGH OVER CENTRAL CANADA INTO
THE FORECAST AREA REMAINS ON TRACK BETWEEN SUNDAY AND MONDAY...WITH
THE TROUGH SLOWLY PUSHING TO THE EAST ON TUESDAY. AS THIS
OCCURS...THERE ARE COUPLE OF ISSUES TO CONTEND WITH...
1. POTENTIAL FOR CONVECTION ON SUNDAY. A SURFACE COLD FRONT IS
PROGGED TO DROP THROUGH THE AREA...THOUGH THERE DOES NOT APPEAR TO
BE MUCH CONVERGENCE ON IT. THE 12.00Z ECMWF/NAM/REGIONAL
CANADIAN/HIRES ARW AND NMM ARE DRY...WHILE THE 12.00Z GFS HAS
REDUCED ITS QPF EVEN MORE. THE GFS STILL HAS TOO HIGH SURFACE
DEWPOINTS IN WHAT SHOULD BE A FAVORABLE MIXING REGIME...THUS PREFER
THE DRIER IDEA.
2. RAIN CHANCES MONDAY THROUGH TUESDAY. AN UPPER LOW WITHIN THE
TROUGH WILL SLIDE ACROSS NORTHERN WI MONDAY EVENING. DPVA FORCING
AHEAD OF THE UPPER LOW AND DAYTIME INSTABILITY SHOULD PROMOTE PLENTY
OF SHOWER ACTIVITY...ESPECIALLY ALONG AND NORTH OF HIGHWAY 29 CLOSER
TO THE UPPER LOW. SOME SHOWER ACTIVITY COULD CONTINUE INTO
TUESDAY...MAINLY IN WISCONSIN CLOSER TO THE UPPER TROUGH AXIS.
3. TEMPERATURES MONDAY AND TUESDAY. 850MB TEMP ANOMALIES PLUMMET TO
2 TO 2.5 STANDARD DEVIATIONS BELOW NORMAL DURING THIS PERIOD...OR
GENERALLY IN THE 4-7C RANGE. THESE READINGS GENERALLY SUPPORT HIGHS
IN THE 60S. HOWEVER...THERE ARE SOME MODEL SUGGESTIONS ON TUESDAY
THAT...DEPENDING ON HOW QUICK THE TROUGH PUSHES EAST...BOTH THE
850MB TEMP AND ACTUAL HIGH COULD BE A LITTLE WARMER. LOWS WILL BE
HELD UP SOMEWHAT BY BOTH CLOUDS AND A NORTHWESTERLY BREEZE. NEEDLESS
TO SAY...ITS GOING TO FEEL MORE LIKE FALL VERSUS SUMMER.
AFTER TUESDAY AND THROUGH THE END OF THE WEEK...EXPECT A LONG DRY
PERIOD AS SURFACE HIGH PRESSURE DOMINATES AND 500MB HEIGHTS RISE.
HOWEVER...THE 12.00Z GFS SHOWS DIURNALLY DRIVEN WIDESPREAD LIGHT
PRECIP WEDNESDAY...THURSDAY AND FRIDAY. THE MODEL APPEARS TO BE
SUFFERING FROM OVER-DOING EVAPOTRANSPIRATION...NOTED IN ITS SURFACE
DEWPOINT FIELD...AND THUS CONVECTS EASIER. THUS...HAVE IGNORED IT
AND STAYED WITH THE DRY ECMWF/CANADIAN.
TEMPERATURES WILL GRADUALLY WARM THROUGH THE WEEK...GETTING CLOSE TO
NORMAL FOR THE WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY NIGHT)
ISSUED AT 635 AM CDT SAT JUL 11 2014
MAIN FLIGHT CONCERNS WILL BE TODAY INTO THE EARLY EVENING HOURS. A
WARM FRONT IN IA WILL SLOWLY LIFT NORTH TODAY. PLENTY OF LOWER LEVEL
MOISTURE ASSOCIATED WITH THIS FRONT WILL SPREAD ACROSS THE AREA...
WITH AREAS OF BR WEST OF THE MS RIVER THIS MORNING AND AREAS OF CIGS
IN THE 2500-4500 FT RANGE AS THE LOWER LEVEL CONTINUE TO SATURATE.
THESE CIGS WILL PERSIST THRU THE DAY INTO THE EVENING. THE FLOW WILL
SWING TO THE WEST AND NORTHWEST LATER THIS EVENING...USHERING IN SOME
DRIER AIR...DECREASING CLOUDS AND VFR CONDITIONS.
SHRA/TSRA REMAIN PROBLEMATIC ACROSS THE FCST AREA/TAF SITES TODAY
INTO THIS EVENING. SIGNAL FOR ONE ROUND OF WEAKENING CONVECTION TO
SPREAD ACROSS THE TAF SITES LATER THIS MORNING INTO EARLY THIS
AFTERNOON...WITH MAINLY VFR VSBYS EXPECTED. ONLY INCLUDED THIS AS
VCSH THRU MID AFTERNOON AT THIS TIME GIVEN CURRENT RADAR TRENDS AND
THE CONTINUED UNCERTAINTIES IN THE EVOLUTION. A STRONGER ROUND OF
SHRA/TSRA EXPECTED TO FIRE LATE THIS AFTERNOON AND SINK SOUTHEAST
ACROSS THE AREA THRU THE LATE AFTERNOON/EARLY EVENING HOURS.
QUESTION REMAINS IF THIS CONVECTION WILL DEVELOP NORTHWEST OF...OVER
OR SOUTHEAST OF THE TAF SITES BEFORE IT BEGINS ITS SOUTHEAST
MOVEMENT. WITH THIS UNKNOWN...ONLY CARRIED A VCTS/CB MENTION AT THE
TAF SITES IN ROUGHLY THE 22-03Z TIME-FRAME FOR NOW. IF THE
CONVECTION DEVELOPS OVER OR NORTHWEST OF THE TAF SITES...WOULD
LIKELY NEED A PERIOD OF TSRA WITH MVFR/IFR VSBYS IN THE DOWNPOURS
FOR A COUPLE HOURS IN THE 22-03Z WINDOW.
&&
.HYDROLOGY...
ISSUED AT 319 AM CDT SAT JUL 12 2014
THERE IS A CONCERN FOR FLASH FLOODING THIS AFTERNOON INTO THIS
EVENING...PRIMARILY ACROSS NORTHEAST IOWA AND FAR SOUTHWEST
WISCONSIN. STORMS IN THIS REGION WILL BE CAPABLE OF PRODUCING VERY
HEAVY RAIN DUE TO A NEARLY TROPICAL AIRMASS IN PLACE. NO FLASH
FLOOD WATCH IS BEING ISSUED AT THIS TIME...THOUGH...BECAUSE OF
1. STRONG 0-3/0-6KM SHEAR WHICH SHOULD KEEP STORMS PROGRESSIVE
2. ANTECEDENT CONDITIONS HAVE DRIED OUT AND CAN TAKE MORE WATER
NEVERTHELESS...SINCE STORMS WILL HAVE HIGH RAINFALL RATES...THERE
COULD BE A NEED FOR A FLASH FLOOD WARNING OR TWO.
&&
.CLIMATE...
ISSUED AT 319 AM CDT SAT JUL 12 2014
RECORD COOL HIGH TEMPERATURES ARE POSSIBLE MONDAY AND TUESDAY AS AN
UNSEASONABLY COLD AIRMASS SETTLES OVER THE UPPER MISSISSIPPI RIVER
VALLEY.
FOR LA CROSSE...
MONDAY....FORECAST HIGH 69. RECORD 65 IN 1994
TUESDAY...FORECAST HIGH 68. RECORD 68 IN 1962
FOR ROCHESTER...
MONDAY....FORECAST HIGH 64. RECORD 64 IN 1952
TUESDAY...FORECAST HIGH 67. RECORD 67 IN 1962
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....RRS
HYDROLOGY....AJ
CLIMATE......AJ
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1133 AM MDT SAT JUL 12 2014
.UPDATE...
ISSUED AT 1026 AM MDT SAT JUL 12 2014
ISSUED FLASH FLOOD WATCH FOR THE EASTERN MOUNTAINS AND INTERSTATE
25 CORRIDOR. VERY MOIST ATMOSPHERE OVER THE REGION WITH
PRECIPITABLE WATERS WELL OVER AN INCH OVER THE PLAINS AND
INTERSTATE 25 CORRIDOR. CONVECTION SHOULD START BY EARLY AFTERNOON
OVER EL PASO AND TELLER COUNTIES AS THE COLD FRONT MOVES
SOUTHWARD INTO INTO HE REGION. OF COURSE...HAVE CONCERNS FOR THE
WALDO CANYON BURN SCAR...BUT OTHER AREAS COULD GET FLOOD RAINS AS
WELL. AS THE FRONT MOVES SOUTHWARD...STORMS WILL DEVELOP FURTHER
SOUTH ALONG THE EASTERN MOUNTAINS AND INTERSTATE 25 CORRIDOR.
HIGH RESOLUTION MODELS SUGGEST THE HEAVIER RAIN WILL PROPAGATE TO
THE EAST DURING THE EVENING...BUT BUFKIT SOUNDING CONTINUE TO
SHOW SOME NORTHEAST FLOW INTO THE EASTERN MOUNTAINS. HAVE CONCERNS
THAT SOME HEAVIER RAIN COULD LINGER OVER THE EASTERN MOUNTAINS
DURING THE EVENING. IF BATCH OF HEAVIER RAIN DEVELOPS OVER THE
EASTERN PLAINS DURING THE EVENING...IT WILL BE WELCOMED RAIN FOR
THE AREAS UNDER SEVERE TO EXTREME DROUGHT. GIVEN THE DROUGHT
CONDITIONS AND DIFFICULTY IN PINPOINTING A SPECIFIC LOCATION FOR
HEAVIER RAIN...WILL NOT ISSUE A WATCH AT THIS TIME. --PGW--
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 441 AM MDT SAT JUL 12 2014
A SHORTWAVE TROF PASSING TO THE NORTH OF THE AREA TODAY WL SEND A
FRONT INTO NE CO...WHICH IS THEN EXPECTED TO MAKE ITS WAY INTO SERN
CO LATE THIS AFTERNOON AND EVENING. CURRENTLY THIS EARLY MORNING
THERE ARE SOME LIGHT ECHOES OVER THE CONTDVD...SO WL HAVE SOME ISOLD
POPS IN THAT AREA FOR THE EARLY MORNING HOURS. HI RES FORECAST
MODELS THEN SHOW CONVECTION DEVELOPING OVR THE MTNS IN THE LATE
MORNING HRS. THE PCPN THEN SPREADS OVR THE SAN LUIS VALLEY AND I-25
CORRIDOR IN THE EARLY AFTERNOON...AND THEN OVR THE SOUTHEAST PLAINS
LATE IN THE AFTERNOON AND IN THE EVENING HOURS. THE WRF AND RAP
SHOW EL PASO COUNTY...ESPECIALLY NRN AND WRN PORTIONS POTENTIALLY
GETTING HIT WITH HEAVY RAIN IN THE LATE AFTERNOON AND EARLY EVENING
HOURS WITH LOW TO MID LEVEL NORTHEAST WINDS. WITH THE FLOW ALOFT
EXPECTED TO ONLY BE AROUND 5 KTS...THAT WOULD LEAD TO SLOW MOVING
STORMS AND THE THREAT OF HEAVY RAIN. AREA BURN SCARS WL BE A CONCERN
IF HEAVY RAIN DEVELOPS...AS WELL AS PORTIONS OF ERN EL PASO COUNTY
THAT RECEIVED HEAVY RAIN LAST EVENING.
IN THE EARLY EVENING HOURS AS THE FRONT MOVES SOUTH TO THE RATON
MESA AREA...THE HEAVY RAIN POTENTIAL MAY SHIFT TO THAT AREA FOR THE
REST OF THE EVENING. THE WRF THEN DECREASES OR END MOST OF THE PCPN
AFTER 06Z. HOWEVER...THE 06Z RUN OF THE NAM12 HAS COME IN WITH
HEAVY RAIN POTENTIAL THRU THE NIGHT OVR THE WET AND SANGRE DE CRISTO
MTNS AND THE ADJACENT LOWER ELEVATIONS. THE NAM IS SHOWING AROUND
2.5 INCHES OF PCPN OVR THE WET MTNS IN THE PERIOD FROM 00Z-12Z
SUN...WITH ABOUT 1-1.5 INCHES OVR SW PUEBLO...HUERFANO AND WRN LAS
ANIMAS COUNTIES...WITH MID LEVEL EASTERLY FLOW AROUND 15 KTS. THE
GFS ALSO PEGS THE SANGRES AND WET AS AN AREA THAT COULD SEE SOME
HEAVIER RAIN OVERNIGHT...HOWEVER ITS AMOUNTS ARE MUCH LESS WHEN
COMPARED TO THE NAM. SINCE THE HRRR AND RAP DO NOT GO OUT THROUGH
THE NIGHT PERIOD YET...WILL JUST GO WITH SOME SCT POPS OVERNIGHT
OVER THE SANGRES AND WETS AND NEARBY LOWER ELEVATIONS AND LET THE
NEXT SHIFT EVALUATE THE HI RES MODEL DATA AS IT COMES IN FOR THE
OVERNIGHT HOURS...ALONG WITH THE NEXT RUN OF THE NAM.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 441 AM MDT SAT JUL 12 2014
...COOL AND WET WEATHER EXPECTED INTO THE MIDDLE OF WORK WEEK...
SUNDAY-SUNDAY NIGHT...WEAK TO MODERATE NORTH TO NORTHWEST FLOW ALOFT
PROGGED ACROSS THE REGION WITH HIGH AMPLITUDE RIDGING BUILDING BACK
ACROSS THE WEST COAST AND GREAT BASIN AS AN UNSEASONABLY STRONG
UPPER LOW DIGS INTO THE UPPER GREAT LAKES REGION. LATEST MODELS ARE
INDICATING SHORT WAVE ENERGY TRANSLATING DOWN THE EASTERN PERIPHERY
OF THE RIDGE ACROSS THE NORTHERN ROCKIES AND NORTHERN HIGH PLAINS
WITH SECONDARY SURGE OF COOL AIR BUILDING INTO THE CENTRAL HIGH
PLAINS AND INTO EASTERN COLORADO. MODELS ARE ALSO INDICATING THE
MAIN MONSOONAL MOISTURE PLUME BEING SHUNTED SOUTH AND WEST OF THE
AREA WITH SOME DRIER AIR EMBEDDED WITHIN THE DEVELOPING NORTHERLY
FLOW SLOWLY WORKING INTO NORTHWESTERN COLORADO. HOWEVER....PRECIP
WATER...IS PROGGED TO REMAIN HIGH ACROSS THE AREA WITH READINGS
BETWEEN 0.75 INCHES AND 1.5 INCHES...GREATEST ACROSS THE EASTERN
PLAINS. THERE COULD BE SOME ONGOING SHOWERS ACROSS THE AREA EARLY
SUNDAY MORNING AS SECONDARY SURGE OF COOL AIR AND LOW LEVEL MOISTURE
BACKS INTO EASTERN COLORADO. WITH AMPLE MOISTURE IN PLACE...ALONG
WITH STRONG SOLAR HEATING AND SOME INCREASED UVV ASSOCIATED WITH
PASSING SHORT WAVE...SHOULD SEE SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS DEVELOPING ACROSS THE HIGHER TERRAIN LATE SUNDAY
MORNING AND AFTERNOON...WITH SCATTERED STORMS SPREADING ACROSS THE
ADJACENT PLAINS THROUGH THE FAR EASTERN PLAINS SUNDAY AFTERNOON AND
EVENING. STORMS WILL BE GENERALLY SLOW MOVING WITH LOCALLY HEAVY
RAINFALL LEADING TO POSSIBLE FLASH FLOODING CONCERNS...ESPECIALLY
ACROSS AREA BURN SCARS. THERE MAY ALSO BE ENOUGH SHEAR ACROSS THE
EASTERN PLAINS FOR A FEW STRONGER STORMS PRODUCING HAIL AND STRONG
WIND GUSTS.
MONDAY-WEDNESDAY...MODERATE NORTHWESTERLY FLOW CONTINUES ACROSS THE
REGION INTO THE MIDDLE OF WORK WEEK WITH THE HIGH AMPLITUDE UPPER
RIDGE PERSISTING ACROSS THE WEST COAST AND GREAT BASIN AS THE
UNSEASONABLY STRONG UPPER LOW OVER THE UPPER GREAT LAKES REGION DIGS
INTO THE CENTRAL CONUS. DRIER AIR EMBEDDED WITHIN THE FLOW ALOFT
CONTINUES TO SLOWLY WORK INTO WESTERN COLORADO...THOUGH PRECIP WATER
LOOKS TO REMAIN HIGH...ESPECIALLY ACROSS THE EASTERN MTS AND PLAINS
WITH CONTINUED MOIST EASTERLY UPSLOPE FLOW IN PLACE AS COOL CANADIAN
HIGH PRESSURE BUILDS THROUGH THE HIGH PLAINS STATES. AGAIN WITH THE
AMPLE MOISTURE IN PLACE...GENERALLY DIURNAL SCATTERED TO NUMEROUS
THUNDERSTORMS CAN BE EXPECTED ACROSS THE AREA...WITH BEST COVERAGE
OVER AND NEAR THE MTS. WITH THE MODERATE FLOW ALOFT...STORMS WILL BE
MOVING...HOWEVER LOCALLY HEAVY RAINFALL TO REMAIN POSSIBLE. WITH
FAIRLY CLOUDY CONDITIONS AND THE MOIST AND COOL UPSLOPE FLOW...
TEMPERATURES ARE EXPECTED TO BE BELOW TO WELL BELOW SEASONAL
AVERAGES THROUGH THE PERIOD.
THURSDAY-FRIDAY...A SLOW WARMING AND DRYING TREND IN THE OFFING INTO
THE UPCOMING WEEKEND WITH MORE WESTERLY FLOW ALOFT DEVELOPING AS
UPPER RIDGE FLATTENS ACROSS THE GREAT BASIN. ENOUGH MOISTURE REMAINS
TO KEEP ISOLATED TO SCATTERED POPS IN THE FORECAST...WITH BEST
COVERAGE REMAINING ACROSS THE MTS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1124 AM MDT SAT JUL 12 2014
VERY MOIST AIR MASS WILL REMAIN OVER THE TAF SITES THROUGH AT
LEAST SUNDAY.
KCOS AND KPUB...THIS AFTERNOON...THUNDERSTORMS WILL DEVELOP IN
THE VICINITY OF KCOS AROUND 2000Z AND KPUB AROUND 2100Z. THE
THREAT OF STORMS WILL CONTINUE INTO THE EVENING. GIVEN THE WIDE
RANGE OF TIMES FOR CONVECTION..DECIDED NOT TO INCLUDE TEMPO
GROUPS AT THIS TIME. WITH MOST LOWER LEVELS...BELIEVE THE MAIN
THREATS FROM STORMS WILL BE HEAVY RAIN WHICH CAN LOCALLY REDUCE
CEILINGS AND VISIBILITIES. PLENTY OF MOISTURE REMAINING TONIGHT.
WITH LIGHT WINDS BEING DOWNSLOPE AT BOTH SITES...DECIDED TO HAVE
VFR CEILINGS OVERNIGHT INSTEAD OF MVFR.
KALS...MOIST AIRMASS WILL REMAIN OVER THE REGION. ANTICIPATE
AFTERNOON AND EARLY EVENING THUNDERSTORMS AROUND THE SAN LUIS
VALLEY. COVERAGE WILL NOT BE HIGH ENOUGH TO HAVE TEMPO GROUP FOR
THUNDERSTORMS. MAIN THREATS WILL BE LOCALLY HEAVY DOWNPOURS AS
WELL AS GUSTY WINDS. CONVECTION WILL END MY MID EVENING WITH VFR
OVERNIGHT. --PGW--
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH THIS EVENING FOR COZ072>088.
&&
$$
UPDATE...PGW
SHORT TERM...28
LONG TERM...MW
AVIATION...PGW
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1042 AM MDT SAT JUL 12 2014
.UPDATE...
ISSUED AT 1026 AM MDT SAT JUL 12 2014
ISSUED FLASH FLOOD WATCH FOR THE EASTERN MOUNTAINS AND INTERSTATE
25 CORRIDOR. VERY MOIST ATMOSPHERE OVER THE REGION WITH
PRECIPITABLE WATERS WELL OVER AN INCH OVER THE PLAINS AND
INTERSTATE 25 CORRIDOR. CONVECTION SHOULD START BY EARLY AFTERNOON
OVER EL PASO AND TELLER COUNTIES AS THE COLD FRONT MOVES
SOUTHWARD INTO INTO HE REGION. OF COURSE...HAVE CONCERNS FOR THE
WALDO CANYON BURN SCAR...BUT OTHER AREAS COULD GET FLOOD RAINS AS
WELL. AS THE FRONT MOVES SOUTHWARD...STORMS WILL DEVELOP FURTHER
SOUTH ALONG THE EASTERN MOUNTAINS AND INTERSTATE 25 CORRIDOR.
HIGH RESOLUTION MODELS SUGGEST THE HEAVIER RAIN WILL PROPAGATE TO
THE EAST DURING THE EVENING...BUT BUFKIT SOUNDING CONTINUE TO
SHOW SOME NORTHEAST FLOW INTO THE EASTERN MOUNTAINS. HAVE CONCERNS
THAT SOME HEAVIER RAIN COULD LINGER OVER THE EASTERN MOUNTAINS
DURING THE EVENING. IF BATCH OF HEAVIER RAIN DEVELOPS OVER THE
EASTERN PLAINS DURING THE EVENING...IT WILL BE WELCOMED RAIN FOR
THE AREAS UNDER SEVERE TO EXTREME DROUGHT. GIVEN THE DROUGHT
CONDITIONS AND DIFFICULTY IN PINPOINTING A SPECIFIC LOCATION FOR
HEAVIER RAIN...WILL NOT ISSUE A WATCH AT THIS TIME. --PGW--
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 441 AM MDT SAT JUL 12 2014
A SHORTWAVE TROF PASSING TO THE NORTH OF THE AREA TODAY WL SEND A
FRONT INTO NE CO...WHICH IS THEN EXPECTED TO MAKE ITS WAY INTO SERN
CO LATE THIS AFTERNOON AND EVENING. CURRENTLY THIS EARLY MORNING
THERE ARE SOME LIGHT ECHOES OVER THE CONTDVD...SO WL HAVE SOME ISOLD
POPS IN THAT AREA FOR THE EARLY MORNING HOURS. HI RES FORECAST
MODELS THEN SHOW CONVECTION DEVELOPING OVR THE MTNS IN THE LATE
MORNING HRS. THE PCPN THEN SPREADS OVR THE SAN LUIS VALLEY AND I-25
CORRIDOR IN THE EARLY AFTERNOON...AND THEN OVR THE SOUTHEAST PLAINS
LATE IN THE AFTERNOON AND IN THE EVENING HOURS. THE WRF AND RAP
SHOW EL PASO COUNTY...ESPECIALLY NRN AND WRN PORTIONS POTENTIALLY
GETTING HIT WITH HEAVY RAIN IN THE LATE AFTERNOON AND EARLY EVENING
HOURS WITH LOW TO MID LEVEL NORTHEAST WINDS. WITH THE FLOW ALOFT
EXPECTED TO ONLY BE AROUND 5 KTS...THAT WOULD LEAD TO SLOW MOVING
STORMS AND THE THREAT OF HEAVY RAIN. AREA BURN SCARS WL BE A CONCERN
IF HEAVY RAIN DEVELOPS...AS WELL AS PORTIONS OF ERN EL PASO COUNTY
THAT RECEIVED HEAVY RAIN LAST EVENING.
IN THE EARLY EVENING HOURS AS THE FRONT MOVES SOUTH TO THE RATON
MESA AREA...THE HEAVY RAIN POTENTIAL MAY SHIFT TO THAT AREA FOR THE
REST OF THE EVENING. THE WRF THEN DECREASES OR END MOST OF THE PCPN
AFTER 06Z. HOWEVER...THE 06Z RUN OF THE NAM12 HAS COME IN WITH
HEAVY RAIN POTENTIAL THRU THE NIGHT OVR THE WET AND SANGRE DE CRISTO
MTNS AND THE ADJACENT LOWER ELEVATIONS. THE NAM IS SHOWING AROUND
2.5 INCHES OF PCPN OVR THE WET MTNS IN THE PERIOD FROM 00Z-12Z
SUN...WITH ABOUT 1-1.5 INCHES OVR SW PUEBLO...HUERFANO AND WRN LAS
ANIMAS COUNTIES...WITH MID LEVEL EASTERLY FLOW AROUND 15 KTS. THE
GFS ALSO PEGS THE SANGRES AND WET AS AN AREA THAT COULD SEE SOME
HEAVIER RAIN OVERNIGHT...HOWEVER ITS AMOUNTS ARE MUCH LESS WHEN
COMPARED TO THE NAM. SINCE THE HRRR AND RAP DO NOT GO OUT THROUGH
THE NIGHT PERIOD YET...WILL JUST GO WITH SOME SCT POPS OVERNIGHT
OVER THE SANGRES AND WETS AND NEARBY LOWER ELEVATIONS AND LET THE
NEXT SHIFT EVALUATE THE HI RES MODEL DATA AS IT COMES IN FOR THE
OVERNIGHT HOURS...ALONG WITH THE NEXT RUN OF THE NAM.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 441 AM MDT SAT JUL 12 2014
...COOL AND WET WEATHER EXPECTED INTO THE MIDDLE OF WORK WEEK...
SUNDAY-SUNDAY NIGHT...WEAK TO MODERATE NORTH TO NORTHWEST FLOW ALOFT
PROGGED ACROSS THE REGION WITH HIGH AMPLITUDE RIDGING BUILDING BACK
ACROSS THE WEST COAST AND GREAT BASIN AS AN UNSEASONABLY STRONG
UPPER LOW DIGS INTO THE UPPER GREAT LAKES REGION. LATEST MODELS ARE
INDICATING SHORT WAVE ENERGY TRANSLATING DOWN THE EASTERN PERIPHERY
OF THE RIDGE ACROSS THE NORTHERN ROCKIES AND NORTHERN HIGH PLAINS
WITH SECONDARY SURGE OF COOL AIR BUILDING INTO THE CENTRAL HIGH
PLAINS AND INTO EASTERN COLORADO. MODELS ARE ALSO INDICATING THE
MAIN MONSOONAL MOISTURE PLUME BEING SHUNTED SOUTH AND WEST OF THE
AREA WITH SOME DRIER AIR EMBEDDED WITHIN THE DEVELOPING NORTHERLY
FLOW SLOWLY WORKING INTO NORTHWESTERN COLORADO. HOWEVER....PRECIP
WATER...IS PROGGED TO REMAIN HIGH ACROSS THE AREA WITH READINGS
BETWEEN 0.75 INCHES AND 1.5 INCHES...GREATEST ACROSS THE EASTERN
PLAINS. THERE COULD BE SOME ONGOING SHOWERS ACROSS THE AREA EARLY
SUNDAY MORNING AS SECONDARY SURGE OF COOL AIR AND LOW LEVEL MOISTURE
BACKS INTO EASTERN COLORADO. WITH AMPLE MOISTURE IN PLACE...ALONG
WITH STRONG SOLAR HEATING AND SOME INCREASED UVV ASSOCIATED WITH
PASSING SHORT WAVE...SHOULD SEE SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS DEVELOPING ACROSS THE HIGHER TERRAIN LATE SUNDAY
MORNING AND AFTERNOON...WITH SCATTERED STORMS SPREADING ACROSS THE
ADJACENT PLAINS THROUGH THE FAR EASTERN PLAINS SUNDAY AFTERNOON AND
EVENING. STORMS WILL BE GENERALLY SLOW MOVING WITH LOCALLY HEAVY
RAINFALL LEADING TO POSSIBLE FLASH FLOODING CONCERNS...ESPECIALLY
ACROSS AREA BURN SCARS. THERE MAY ALSO BE ENOUGH SHEAR ACROSS THE
EASTERN PLAINS FOR A FEW STRONGER STORMS PRODUCING HAIL AND STRONG
WIND GUSTS.
MONDAY-WEDNESDAY...MODERATE NORTHWESTERLY FLOW CONTINUES ACROSS THE
REGION INTO THE MIDDLE OF WORK WEEK WITH THE HIGH AMPLITUDE UPPER
RIDGE PERSISTING ACROSS THE WEST COAST AND GREAT BASIN AS THE
UNSEASONABLY STRONG UPPER LOW OVER THE UPPER GREAT LAKES REGION DIGS
INTO THE CENTRAL CONUS. DRIER AIR EMBEDDED WITHIN THE FLOW ALOFT
CONTINUES TO SLOWLY WORK INTO WESTERN COLORADO...THOUGH PRECIP WATER
LOOKS TO REMAIN HIGH...ESPECIALLY ACROSS THE EASTERN MTS AND PLAINS
WITH CONTINUED MOIST EASTERLY UPSLOPE FLOW IN PLACE AS COOL CANADIAN
HIGH PRESSURE BUILDS THROUGH THE HIGH PLAINS STATES. AGAIN WITH THE
AMPLE MOISTURE IN PLACE...GENERALLY DIURNAL SCATTERED TO NUMEROUS
THUNDERSTORMS CAN BE EXPECTED ACROSS THE AREA...WITH BEST COVERAGE
OVER AND NEAR THE MTS. WITH THE MODERATE FLOW ALOFT...STORMS WILL BE
MOVING...HOWEVER LOCALLY HEAVY RAINFALL TO REMAIN POSSIBLE. WITH
FAIRLY CLOUDY CONDITIONS AND THE MOIST AND COOL UPSLOPE FLOW...
TEMPERATURES ARE EXPECTED TO BE BELOW TO WELL BELOW SEASONAL
AVERAGES THROUGH THE PERIOD.
THURSDAY-FRIDAY...A SLOW WARMING AND DRYING TREND IN THE OFFING INTO
THE UPCOMING WEEKEND WITH MORE WESTERLY FLOW ALOFT DEVELOPING AS
UPPER RIDGE FLATTENS ACROSS THE GREAT BASIN. ENOUGH MOISTURE REMAINS
TO KEEP ISOLATED TO SCATTERED POPS IN THE FORECAST...WITH BEST
COVERAGE REMAINING ACROSS THE MTS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 441 AM MDT SAT JUL 12 2014
COULD SEE SOME STRATUS THIS MORNING AT KCOS AND KPUB...OTHERWISE
EXPECTED MAINLY VFR CONDITIONS AT THESE SITES TODAY AND TONIGHT.
HOWEVER...WITH THE POTENTIAL FOR SOME HEAVY RAIN THIS AFTERNOON AND
EVENING THERE COULD BE BRIEF PERIODS OF MVFR CONDITIONS ASSOCIATED
WITH THE RAIN. KALS SHOULD GENERALLY SEE VFR CONDITIONS TODAY AND
TONIGHT...BUT IT THUNDERSTORMS MOVE OVER THE AREA...THERE COULD BE
BRIEF PERIODS OF MVFR CONDITIONS AS A RESULT OF HEAVY RAIN.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH THIS EVENING FOR COZ072>088.
&&
$$
UPDATE...PGW
SHORT TERM...28
LONG TERM...MW
AVIATION...28
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1036 AM MDT SAT JUL 12 2014
.UPDATE...
ISSUED AT 1036 AM MDT SAT JUL 12 2014
A VERY MOIST AIRMASS WILL BE OVER THE AREA TODAY. DEW POINTS ARE
HIGHER THAN YESTERDAY WITH READINGS IN THE UPPER 50S AND LOWERS 60S.
WATER VAPOR SHOWING SLIGHT DRYING AT THE UPPER LEVELS...SO EXPECT
PRECIPITABLE WATER VALUES TO REMAIN IN THE INCH TO 1.25 RANGE
THROUGH THIS EVENING. DIFFICULT TO TELL FOR SURE...BUT MAY BE A WEAK
WAVE SHOWING UP ON WATER VAPOR OVER WESTERN COLORADO. THIS WILL HELP
TO TRIGGER THUNDERSTORMS TODAY. CLOUDS OVER THE AREA THIS MORNING
WILL LIMIT HEATING. EXPECT STORMS TO FIRST FORM OVER THE MOUNTAINS
AND FOOTHILLS...AND THEN SPREAD EAST TO SOUTHEAST AS OUTFLOW
BOUNDARIES KICK OFF ADDITIONAL STORMS.
MAIN CONCERN WILL BE THE THREAT FOR HEAVY RAIN. EXPECT STORMS TO
MOVE EAS TO SOUTHEAST AT 10 TO 15 MPH. THE FLASH FLOOD THREAT WILL
BE SLIGHTLY HIGHER THAN YESTERDAY. IT WILL LIKELY TAKE MULTIPLE
STORMS OR STORMS REGENERATING OVER THE SAME AREA FOR FLASH FLOODING.
HOWEVER IT MAY ONLY TAKE ONE STRONG STORM TO PRODUCE FLASH FLOOD IN
FLOOD PRONE AREAS. THE WIND PROFILE FAVORS A FEW BACK BUILDING
STORMS. PLUS THE AND HRRR DOES SHOW SOME REGENERATION AND TRAINING
OF STORMS. WILL HOIST A FLASH FLOOD WATCH FOR THE DENVER AREA AND
SOUTH. DRIER AIR WILL MOVE INTO THE AREA THIS EVENING AND HELP BRING
CONVECTION TO END EARLIER TONIGHT AND ALSO LOWER THE FLASH FLOOD
THREAT NORTH.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 458 AM MDT SAT JUL 12 2014
ONLY MINOR CHANGES MADE THIS MORNING. TODAY IS LOOKING MUCH LIKE
YESTERDAY. THERE ARE A FEW SUBTLE DIFFERENCES THAT MAY LEAD TO AN
INCREASED HEAVY RAIN POTENTIAL THIS AFTERNOON. PRECIPITABLE WATER
IS STILL RUNNING AROUND 1.25 INCHES. SURFACE DEW POINTS HAVE CREPT
UP INTO THE LOWER 60S IN MOST AREAS...WHICH MEANS THE WARM CLOUD
LAYER WILL BE INCREASED TO AROUND 5000 FEET TODAY ENHANCING RAIN
EFFICIENCY. STEERING WINDS LOOK LIKE THEY WILL BECOME A BIT
STRONGER BY AFTERNOON...FROM THE WNW AT 10-15 MPH. HOWEVER THE LOW
LEVEL WINDS WILL BE FROM THE NORTH TO NORTHEAST...A BIT BEHIND THE
STORM...WHICH COULD LEAD TO A BETTER CHANCE OF BACKBUILDING
RESULTING IN A SLOWER EFFECTIVE MOTION. CAPES SHOULD WIND UP IN
THE 800-1600 J/KG RANGE ON THE PLAINS...ENOUGH FOR STRONG
UPDRAFTS...WHILE SHEAR SHOULD BE LOWER THAN YESTERDAY.
SO IN GENERAL IT STILL LOOKS LIKE THERE SHOULD BE POCKETS OF
HEAVY RAIN...BUT A LOW RISK OF FLASH FLOODING. OF COURSE THE
THREAT IS HIGHER FOR THE FOOTHILLS BURN/FLOOD DAMAGE AREAS...URBAN
AREAS AND PLACES THAT GOT SIGNIFICANT RAIN LAST NIGHT.
MODELS SHOW CONVECTION DEVELOPING IN THE FOOTHILLS BY EARLY
AFTERNOON AND MOVING SOUTHEAST INITIALLY...THEN TURNING INTO ONE
OR MORE CLUSTERS MOVING MORE SOUTHERLY BY EVENING. SOME POTENTIAL
FOR THE NORTHEAST CORNER TO MISS OUT AS IT MAY BE A LITTLE TOO
COOL AND THE STORM MOTION MAY DRIVE EVERYTHING SOUTH OF THERE. WE
ALREADY HAVE A GRADIENT DRAWN LIKE THAT. IF THE MID LEVEL CLOUDS
DISSIPATE ENOUGH IT WOULD GET A BIT WARMER THAN FORECAST AND
CONVECTION ON THE PLAINS WOULD LIKELY BE MORE WIDESPREAD.
A WEAK SHORTWAVE WILL COUPLE WITH THE DIURNAL CONVECTION TO BRING
THE PEAK ACTIVITY IN THE AFTERNOON ACROSS MOST OF THE AREA WITH A
LITTLE DRYING COMING IN FROM THE NORTH THIS EVENING.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 458 AM MDT SAT JUL 12 2014
ON MONDAY...THE UPPER RIDGE WILL BE CENTERED OVER NEVADA/UTAH WITH
A PERSISTENT NORTHWESTERLY FLOW OVER NERN CO. A SYSTEM PASSING TO
THE NORTHEAST WILL PUSH ANOTHER COLD FRONT INTO THE NERN PLAINS.
THE MAIN FOCUS FOR TSTMS WILL BE ALONG THE FRONT RANGE FOOTHILLS
AND PALMER DIVIDE...WHERE THE FRONTAL BOUNDARY WILL BECOME
STATIONARY. PW VALUES WILL BE AROUND 0.90 INCHES AT DENVER BY LATE
AFTERNOON...WITH SFC BASED CAPES AROUND 350 J/KG. STORM MOTIONS
PRETTY DECENT...20-25 KTS...SO HEAVY RAINFALL SHOULD BE BRIEF. A
SIMILAR SYNOPTIC PATTERN WILL BE IN PLACE ON TUESDAY. THE
NORTHWESTERLY FLOW ALOFT WILL CONTINUE ON WEDNESDAY. ANOTHER
SYSTEM IS EXPECTED TO DROP OUT OF THE NRN ROCKIES AND WASH OUT
ACROSS NERN CO ON WEDNESDAY. AS A RESULT...ANOTHER SURGE AND
CORRESPONDING UPSLOPE WILL BRING WITH IT A PERSISTENT CHANCE OF
THUNDERSTORMS WEDNESDAY AFTERNOON AND NIGHT. THE FLOW ALOFT WILL
REMAIN NORTHWESTERLY ON THURSDAY AND FRIDAY...WITH A LESSENING
CHANCE OF THUNDERSTORMS AS THE AIRMASS DRIES OUT...ESPECIALLY ON
FRIDAY.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z SUNDAY MORNING)
ISSUED AT 1036 AM MDT SAT JUL 12 2014
LOW CLOUDS WILL SLOWLY RISE AND BURN OFF BY 18Z. CEILINGS WILL BE
ABOVE 1500 TO 2500 FEET. THUNDERSTORMS WILL LIKELY IMPACT THE DENVER
AIRPORTS TODAY SOMETIME BETWEEN 20Z AND 01Z. HEAVY RAIN...HAIL AND
STRONG WINDS WILL BE POSSIBLE WITH THE STORMS. NORTHEAST WINDS WILL
PREVAIL OUTSIDE OF THUNDERSTORMS.
&&
.HYDROLOGY...
ISSUED AT 458 AM MDT SAT JUL 12 2014
SLOW MOVING STORMS IN A MOIST AIRMASS WILL AGAIN HAVE POTENTIAL TO
PRODUCE HEAVY RAIN TODAY. THE STRONGER STORMS WILL PRODUCE ONE TO
TWO INCHES OF RAIN IN AN HOUR...WHICH WOULD PROVIDE SOME POTENTIAL
FOR FLOODING. THERE MAY BE A FEW CASES IN WHICH STORMS STALL AND
PRODUCE EVEN HEAVIER RAIN OVER A COUPLE OF HOURS. THE GREATEST
THREAT OF FLOODING WILL LIKELY BE WITH THE INITIAL STORMS...
ESPECIALLY IN THE EARLY TO MID AFTERNOON IN AND NEAR THE
FOOTHILLS.
OVERALL THE AIRMASS WILL REMAIN MOIST ON SUNDAY WITH A CONTINUED
CHANCE OF MAINLY AFTERNOON AND EVENING THUNDERSTORMS. AS A
RESULT...BRIEF HEAVY RAIN WILL BE THE PRIMARY THREAT. THE STORM
MOTIONS ARE EXPECTED TO BE AROUND 15 MPH...WHICH SHOULD HELP
OFFSET THE FLASH FLOOD THREAT. THERE WILL BE A PERSISTENT THREAT
OF MAINLY AFTERNOON AND EVENING THUNDERSTORMS THROUGH THE MIDDLE
OF NEXT WEEK. THE GENERAL PATTERN WILL CHANGE VERY LITTLE.
CONSEQUENTLY LOCALLY HEAVY RAINFALL WILL REMAIN THE PRIMARY
CONCERN.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 9 PM MDT THIS EVENING FOR COZ036-039>041.
&&
$$
UPDATE...MEIER
SHORT TERM...GIMMESTAD
LONG TERM...COOPER
AVIATION...MEIER
HYDROLOGY...COOPER/GIMMESTAD
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
329 PM EDT SAT JUL 12 2014
.PREV DISCUSSION... /ISSUED 720 AM EDT SAT JUL 12 2014/
PREV DISCUSSION... /ISSUED 433 AM EDT SAT JUL 12 2014/
SHORT TERM /TODAY THROUGH SUNDAY/...
WEAK BOUNDARY STILL SITUATED ACROSS CENTRAL GA THIS MORNING. THE
BOUNDARY IS VERY DIFFUSE AND IS ONLY BARELY NOTED IN THE TEMP/DEW
FIELDS. REGIONAL RADAR SHOWS ALL THE EARLIER SHOWER ACTIVITY HAS
DIMINISHED ACROSS THE CWFA EARLY THIS MORNING.
POP COVERAGE SHOULD BE LESS TODAY THAN IN PREVIOUS DAYS. THE FRONT
WILL CONTINUE TO BECOME MORE DIFFUSE WHILE PUSHING SOUTHWARD AS HIGH
PRESSURE ACROSS THE MIDDLE ATLANTIC BUILDS DOWN THE SPINE OF THE
APPALACHIAN MOUNTAINS. WILL HAVE THE HIGHEST POPS IN THE SOUTHERN
QUARTER OF THE CWFA...NEAREST THE SURFACE BOUNDARY. IN
ADDITION...THE HRRR IS SHOWING SOME ISOLD/LOW END SCT DEVELOPMENT
ACROSS THE HIGHER TERRAIN THIS AFTERNOON.
PWATS ARE A LITTLE HIGHER THAN YESTERDAY...WITH THE DEEPEST MOISTURE
STILL SOUTH OF THE WEAKENING BOUNDARY. HOWEVER...WITH BL WINDS AT OR
BLO 15 KT...STORM MOVEMENT SHOULD BE SLOW. THIS MAY ALSO LEAD TO ANY
STORMS DEVELOPING ACROSS NE GA TO STAY LOCKED ON THE HIGHEST
TERRAIN...LEADING TO LOCALLY HEAVY RAINFALL.
DO THINK CONVECTION WILL MOSTLY BE DIURNAL IN NATURE...AND BEGIN
DIMINISHING WITH THE SETTING SUN. CONVECTION SHOULD BE PULSE...WITH
HIGH CAPE AND LOW SHEAR. MID LEVEL LAPSE RATES REMAIN WEAK...AND
CAN`T FIND ANY SIGNIFICANT SHORTWAVES IN THE FLOW. SO...WIDESPREAD
SEVERE THUNDERSTORMS ARE NOT ANTICIPATED...EITHER TODAY OR SUNDAY
BUT A FEW STRONG STORMS WILL HAVE THE POTENTIAL TO PRODUCE LOCALLY
HEAVY RAINFALL AND GUSTY WINDS. THERE IS A LITTLE POTENTIAL FOR AN
ISOLD SEVERE STORM EACH DAY. CONVECTIVE COVERAGE FOR SUNDAY SHOULD
BE EVEN LESS THAN TODAY.
WITH LESSER CONVECTIVE COVERAGE...TEMPS WILL BE WARMER.
NLISTEMAA
LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
NO IMPACT WEATHER EXPECTED IN THE LONG TERM PERIOD. PATTERN STILL
EXPECTED TO BECOME DOMINATED BY LARGE UPPER TROUGH OVER THE ERN
CONUS BY TUES AND PERSIST THRU FRIDAY. 00Z MED RANGE MODEL
GUIDANCE AGAIN IN GOOD AGREEMENT. FRONT ASSOCIATED WITH LEADING
EDGE OF WESTERLIES TO MOVE INTO STATE ON TUES SO BUMPED POPS TO
LIKELY. AS MODEL GUIDANCE STARTS TO HONE IN ON SPECIFICS AND WITH
LESS WEIGHT ON CLIMATOLOGY...BEGINNING TO APPEAR THAT TUES/WED
WILL BE SIGNIFICANTLY DRIER AND MODERATELY COOLER THAN NORMAL
AFTER FROPA. WED MAX TEMPS MAY REMAIN IN THE 70S IN HIGHER
ELEVATIONS OF NORTH GA. DEWPOINTS SHOULD BE IN THE 50S. AS FRONT
WASHES OUT AND LIFTS NORTH THURS/FRI WILL LIKELY SEE RETURN TO SCT
DIURNAL SHOWERS AND THUNDERSTORMS. USED DYNAMIC BLEND FOR FORECAST
TEMPS WHICH WEIGHTS RAW MODELS AND UNCORRECTED MOS GUIDANCE IN AREAS
OF RAIN AND CLOUDS AND BIAS CORRECTED MOS GUIDANCE IN AREAS OF NO
RAIN AND LESS CLOUDS.
SNELSON
&&
.AVIATION...
18Z UPDATE...
GENERALLY VFR CONDITIONS EXPECTED THROUGH THE PERIOD. DIURNAL CU
EXPECTED TO DIMINISH INTO THE EVENING HOURS...AND DEVELOP AGAIN BY
LATE MORNING SUNDAY. ESE WINDS EXPECTED INTO THE OVERNIGHT
PERIOD...AND WITH SE/S BY SUNDAY MORNING...EXPECT FOG TO BE A
PROBLEM IN THE SOUTHERN AND SOUTHEASTERN PORTIONS OF THE STATE.
HAVE INCLUDED MENTION OF LOWER VSBYS 09-14Z FOR CSG...MCN...AND
AHN. RAIN/TS CHANCES LOW ENOUGH NOT TO INCLUDE IN THE TAFS AT THIS
TIME. WINDS SWITCH TO THE SW SUNDAY MORNING...AFTER 14Z.
//ATL CONFIDENCE...18Z UPDATE...
HIGH CONFIDENCE ON ALL ELEMENTS...EXCEPT FOR MEDIUM CONFIDENCE
09-14Z.
31
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 91 71 93 70 / 30 30 20 10
ATLANTA 90 73 92 73 / 20 20 20 10
BLAIRSVILLE 85 66 86 63 / 30 30 30 10
CARTERSVILLE 91 71 93 69 / 20 20 20 10
COLUMBUS 92 74 94 73 / 30 30 20 10
GAINESVILLE 88 70 91 72 / 30 30 20 10
MACON 91 72 93 69 / 30 30 20 10
ROME 92 72 93 70 / 20 20 20 10
PEACHTREE CITY 90 71 92 69 / 20 20 20 10
VIDALIA 89 73 93 72 / 30 30 30 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...31
LONG TERM....ARG
AVIATION...31
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
556 PM CDT SAT JUL 12 2014
.MESOSCALE DISCUSSION...555PM
LOCAL AREA CONTINUES TO DESTABILIZE EARLY THIS EVENING...ESPECIALLY
ACROSS SOUTHWESTERN COUNTIES IN THE CWA WHERE PARTIAL CLEARING AND
STRONG SOUTHWEST WINDS HAVE ALLOWED TEMPERATURES TO WARM INTO THE
LOWER TO MID 80S WITH DEWPOINTS INTO THE MID 70S. FARTHER NORTH
AND NORTHEAST MORE EXTENSIVE CLOUD COVER HAS HAMPERED
DESTABILIZATION TO SOME DEGREE...HOWEVER 22Z AMDAR SOUNDING OUT OF
ORD PAIRED WITH NAM MOISTURE PROFILES INDICATES AROUND 1000 J/KG
MLCAPE WITH AROUND 100 J/KG MLCIN TO OVERCOME. THIS LINES UP WELL
WITH SPC MESOANALYSIS SHOWING THE CAP OVER THE NORTHEAST CORNER OF
IL WITH OVER 2000 J/KG MLCAPE OVER THE SOUTHWEST WHICH IS MOSTLY
UNCAPPED. SHEARED VORT LOBE IS DRIVING EAST ACROSS MN/IA AND WI
CURRENTLY AND HAS PROVIDED SOME BROAD SCALE ASCENT TO KICK OFF A
FEW THUNDERSTORMS ALONG A FRONTAL BOUNDARY THAT STRETCHES FROM
SOUTH CENTRAL IA TO NEAR THE QUAD CITIES WHERE PWATS HAVE POOLED
TO AROUND 2 INCHES. A CORRIDOR OF 40+ KT 0-6KM SHEAR WILL SUPPORT
ORGANIZED THUNDERSTORMS AS ALREADY EVIDENT BY THE SUPERCELL NORTH
OF THE QUAD CITIES. EXPECT LINE OF STORMS TO CONTINUE TO FILL IN
AS THE EVENING PROGRESSES WITH A STEADY FEED OF MOISTURE INTO THE
REGION AS 40-50 KT LOW LEVEL JET DEVELOPS LATER THIS EVENING
HELPING TO MAINTAIN THUNDERSTORMS THROUGH THE LATE EVENING AND
OVERNIGHT HOURS. AS PREVIOUSLY DISCUSSED...HEAVY RAIN AND STRONG
WINDS STILL APPEAR TO BE THE PRIMARY THREATS THIS EVENING AND
TONIGHT.
DEUBELBEISS
510 PM CDT...
STORMS ARE INITIATING ACROSS SOUTHERN AND EASTERN IA AND HAVE
PROMPTED THE ISSUANCE OF A TORNADO WATCH THAT EXTENDS AS FAR EAST
AS NORTHWEST IL. LATEST HAND SURFACE ANALYSIS INDICATES A POOL OF
75+ DEW POINTS ACROSS SOUTHEAST IA INTO CENTRAL IL ADVANCING
NORTHWARD WITH MANY SURFACE OBS IN THIS AREA INDICATING
GUSTINESS. AT THE LEADING EDGE OF THIS A WARM FRONT WITH STRONG
MOISTURE CONVERGENCE IS INCHING NORTHWARD NEAR INTERSTATE 88
AHEAD OF A 1012MB SFC LOW IN CENTRAL IA. SUCH A SETUP OF A SLOWING
NORTHWARD-MOVING WARM FRONT AHEAD OF A NOT-TOO-STRONG LOW PRESSURE
WITH GOOD REPLENISHING MOISTURE REALLY SPELLS TROUBLE FOR HEAVY
RAINFALL TONIGHT WITHIN THE REGION. MOST FAVORED THIS EVE WOULD BE
ALONG AND IMMEDIATELY NORTH OF THIS WARM FRONTAL AXIS...SO THE
NORTHERN FORECAST AREA INCLUDING ROCKFORD. AS CONVECTION
EVOLVES/EXPANDS EASTWARD THROUGH MID-LATE EVENING...SOME
SOUTHWARD PROGRESSION IS THEN LIKELY INTO OVERNIGHT. SO THE ENTIRE
AREA REMAINS UNDER AN INCREASING RISK FOR HEAVY RAINFALL CAPABLE
OF FLASH FLOODING...WHICH OBSERVATIONAL TRENDS SUPPORT.
SEVERE WEATHER THREAT REMAINS AS MENTIONED IN PREV DISCUSSION.
MTF
&&
.DISCUSSION...
311 PM CDT
THIS AFTERNOON...
THE SURFACE LOW IS OVER NORTHERN MANITOBA AND THE UPPER LEVEL LOW IS
STACKED JUST ABOVE IT. STILL HAVE MOSTLY CLOUD SKIES WITH A FEW
BREAKS OF SUN AND WE ARE SLOWLY RECOVERING FROM THIS MORNING/S
CONVECTION. THE 18Z DVN SOUNDING FEATURED 1.7 INCHES OF PWAT AND
AROUND 1500 J/KG OF CAPE. THE SOUNDING ALSO HAD A STOUT CAP AT 850MB
WHICH MATCHES WELL WITH THE LATEST AMDAR SOUNDINGS. LAPSE RATES TO
950 MB WERE SURPRISINGLY STEEP GIVEN THE THICK CLOUD COVER. WITH THE
CAP IN PLACE AND SLOW RECOVERY NOT EXPECTING MUCH CONVECTIVE
ACTIVITY AHEAD OF THE MAIN LINE OF STORMS. IN GENERAL EXPECTING
CLOUDS TO CONTINUE THIN AND TEMPS RISE INTO THE MID 80S BY LATE THIS
AFTN. IT WILL CONTINUE TO BE MUGGY AS PWAT VALUES INCREASE TO
AROUND 2 INCHES.
THIS EVENING AND TONIGHT...
AN UPPER LEVEL SHORTWAVE CURRENTLY OVER IOWA WILL MOVE OVER THE CWA
THIS EVENING ADDING FORCING FOR STORMS. A SURFACE LOW IS OVER
NORTHERN MANITOBA AND ITS COLD FRONT STRETCHES FROM NORTHWEST
WISCONSIN THROUGH CENTRAL IOWA. A LINE OF STORMS WILL FORM ALONG
THE FRONT AND SLOWLY PUSH SOUTH THROUGH THE CWA THIS EVENING AND
OVERNIGHT. 850MB STEERING FLOW WILL BE WEST AT 30-40 KT AHEAD OF THE
LINE BUT ONLY AROUND 15 KT FROM THE NORTH BEHIND THE FRONT. TIMING
DIFFERS BETWEEN THE MODELS BUT THINKING A BLEND OF OUR LOCAL ARW AND
THE RAP LOOK REASONABLE. THE NAM LOOKS TOO FAST WHILE THE HRRR LOOKS
TOO SLOW.
THE LINE MAY PRODUCE SEVERE WIND GUSTS IN EXCESS OF 60 MPH...BUT THE
MAIN CONCERN WILL BE FLASH FLOODING. PWAT VALUES REMAIN HIGH AT
1.7-1.8 INCHES AND VALUES WILL INCREASE TO AROUND 2 INCHES BY THIS
EVENING. HAVE ISSUED A FLASH FLOOD WATCH FOR THE ENTIRE WARNING
AREA FOR THIS EVENING THROUGH TOMORROW MORNING. TOTAL RAINFALL FROM
THIS STORM WILL BE IN EXCESS OF 1 INCH. THE HIGHEST TOTALS WILL
LIKELY BE ALONG THE IL/WI STATE LINE WHERE RAINFALL TOTALS WILL
EASILY APPROACH 2 INCHES. IN ADDITION...SOME AREAS THIS MORNING
FROM COOK COUNTY SOUTH THROUGH PONTIAC AND GIBSON CITY SAW MULTIPLE
INCHES OF RAIN OVERNIGHT INTO THIS MORNING. THESE AREAS WILL BE THE
MOST SUSCEPTIBLE TO FLASH FLOODING AS WATER LEVELS ARE ALREADY
HIGH.
TEMPERATURES WILL QUICKLY FALL BEHIND THE LINE OF STORMS AND LOWS
WILL BE IN THE UPPER 60S TO LOWER 70S.
SUNDAY AND MONDAY...
THE UPPER LEVEL LOW SPLITS SUNDAY NIGHT AND THE FIRST TROUGH AXIS
MOVES THROUGH MONDAY NIGHT. AT THE SURFACE A SECOND COLD FRONT
MOVES THROUGH SUNDAY AND THEN STALLS OUT JUST SOUTH OF THE CWA
MONDAY MORNING. THE HIGHEST INSTABILITY VALUES WILL BE SOUTH OF I-80
SO ONLY HAVE A CHANCE OF STORMS SOUTH OF I-80. NOT EXPECTING MUCH IN
THE WAY OF PRECIP AT THIS TIME.
A BAND OF SHOWERS AND STORMS MAY FORM SUNDAY NIGHT FIRST ALONG THE
IL/WI STATE LINE AND THEN SPREAD SOUTH AS A VORTICITY STREAMER FROM
THE UPPER LEVEL LOW PUSHES SOUTH THROUGH THE REGION. THE SHOWERS
MAY PERSIST INTO LATE SUNDAY NIGHT AND BY THEN ONLY EXPECTING
SHOWERS. CONFIDENCE IS MEDIUM WITH THE STORMS DEVELOPING AND
COVERAGE.
YET ANOTHER COLD FRONT COMES THROUGH MONDAY AND HAVE A CHANCE OF
SHOWERS AND STORMS MONDAY AFTERNOON AND EVENING. THE BIGGER STORY
WILL BE THE COOL AIR THAT FOLLOWS THE COLD FRONT. HIGHS ON SUNDAY
WILL BE IN THE LOWER 80S WHILE MONDAY/S HIGHS WILL BE IN THE MID TO
UPPER 70S. MONDAY NIGHT LOOKS CRISP WITH LOWS IN THE LOWER 50S.
EXTENDED...TUESDAY THROUGH FRIDAY...
THE UPPER LEVEL TROUGH SLOWLY LIFTS NE THROUGH THURSDAY WHILE A
SURFACE HIGH BUILDS OVER THE REGION TUESDAY NIGHT. THE EXTENDED
LOOKS DRY WITH BELOW NORMAL TEMPERATURES.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* LOW CHANCE OF SHRA/TSRA BETWEEN 00Z AND 02Z...SHRA/TSRA EXPECTED
SOME TIME AROUND MID EVENING INTO EARLY OVERNIGHT. HEAVY
RAINFALL WITH IFR VISIBILITY AT TIMES BECOMING MORE LIKELY. WILL
LIKELY INCLUDE TEMPO IN 00Z TAFS FOR VISIBILITY OF 1 SM OR
POSSIBLY LOWER.
* CHANCE FOR MVFR CIGS TO LINGER INTO SUNDAY MORNING.
MTF/MDB
//DISCUSSION...UPDATED 20Z...
NO MAJOR CHANGES IN THINKING AT THIS POINT. CUMULUS IS STARTING TO
DEVELOP ALONG A NARROW LINE FROM SOUTHWEST IOWA NORTHEASTWARD UP
TOWARDS DBQ ALONG THE FRONTAL BOUNDARY THAT WILL IMPACT THE
TERMINALS THROUGH THE EVENING. EXPECT THAT THIS WILL EVOLVE INTO
THUNDERSTORMS OVER THE NEXT FEW HOURS WITH ACTIVITY POTENTIALLY
DEVELOPING INTO FAR NORTHWEST ILLINOIS...AND POSSIBLY RFD IN A FEW
HOURS. OVERALL TIMING SPECIFICS AT THE TERMINALS IS STILL SOMEWHAT
UNCERTAIN BUT DO NOT SEE MUCH TO SUPPORT ANY IMMEDIATE CHANGES.
OTHERWISE...MVFR CIGS HAVE BEEN SCATTERING THOUGH SOME BROKEN PATCH
MAY REMAIN ACROSS NORTH CENTRAL ILLINOIS.
FROM 18Z...
SOUTHWEST WINDS ARE STARTING TO INCREASE IN SPEED WITH GUSTS IN
THE 20-25 KT RANGE. CIGS ARE STARTING TO IMPROVE WITH MAINLY MVFR
IN PLACE. A LOOK OUT THE WINDOW AT THE OFFICE SHOWS STEADY
SCATTERING OF THE LOWEST CLOUDS WHICH SUPPORTS THE THINKING THAT
IMPROVEMENT TO VFR WILL OCCUR OVER THE NEXT FEW HOURS. FOCUS TURNS
TO TIMING OF SHRA/TSRA INTO THE EVENING. NOT MUCH IN THE WAY OF
FOCUS FOR DEVELOPMENT THROUGH MID AFTERNOON BUT FORCING WILL
INCREASE FAR NORTHWEST LATE THIS AFTERNOON. SOME SCATTERED
ACTIVITY IS POSSIBLE UP TOWARDS RFD BY THEN BUT THE FOCUS FOR THE
MOST WIDESPREAD DEVELOPMENT WILL BE ALONG A FRONTAL BOUNDARY FROM
SOUTHERN WISCONSIN WEST-SOUTHWEST INTO EASTERN IOWA. THIS ACTIVITY
WILL SAG SOUTHWARD THIS EVENING. TIMING IS STILL IN QUESTION SO
FURTHER ADJUSTMENTS MAY BE NEEDED BUT AT THIS POINT EARLY EVENING
IS FAVORED AT RFD WITH MID EVENING IN THE CHICAGO AREA AND
SLIGHTLY LATER AT GYY AS THINGS SAG SOUTHWARD. THE FRONT WILL BE
FAIRLY SLOW TO MOVE SO TRAINING OF STORMS ALONG THE FRONT IS
EXPECTED LEADING TO A FAIRLY LONG DURATION OF THUNDER. TORRENTIAL
RAINFALL MAY BRING VSBY DOWN BELOW 1SM BUT WILL HOLD OFF ON THIS
DETAIL IN THE TAF UNTIL IT BECOMES MORE CLEAR. WINDS MAY BE
ERRATIC OVERNIGHT BEHIND THE FRONT BUT TREND TO WEST THEN
NORTHWEST INTO SUNDAY MORNING. MVFR MAY LINGER BEHIND THE FRONT AS
WELL BUT VFR SHOULD BUILD IN.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* MEDIUM IN WINDS...BUT HIGH THEY WILL REMAIN FROM THE SOUTHWEST
THROUGH AT LEAST 01Z.
* HIGH THAT CHANCE FOR TSRA WILL WAIT UNTIL AFTER 00Z. HIGH THAT
TSRA WILL OCCUR TONIGHT...MEDIUM IN TIMING. HIGH THAT TEMPORARY
IFR VISIBILITY WILL OCCUR.
* MEDIUM-HIGH IN CIGS REMAINING VFR UNTIL TSRA.
MTF/MDB
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY-MONDAY...LOW CHANCES OF TSRA.
TUESDAY...SLIGHT CHANCE OF SHRA.
WEDNESDAY-THURSDAY...VFR LIKELY.
KMD
&&
.MARINE...
423 PM CDT
SOUTHERLY FLOW PERSISTING OVER THE ENTIRE LAKE THIS AFTERNOON AS
HIGH PRESSURE REMAINS SITUATED OVER THE ATLANTIC COAST...AND AS A
TROUGH OF LOW PRESSURE AND ASSOCIATED FRONTAL BOUNDARY ARE JUST
WEST OF THE LAKE. AS THESE SOUTHERLY WINDS BECOME MORE SOUTHWEST
AND THEN EVENTUALLY WEST TONIGHT WITH THE PASSAGE OF THIS
TROUGH...DO EXPECT SPEEDS TO REMAIN IN THE 10 TO 20 KT RANGE.
EXPECTED COMPLEX OF SHOWERS AND THUNDERSTORMS WILL LIKELY PROVIDE
ERRATIC WINDS LATER THIS EVENING AND OVERNIGHT...AS WELL AS THE
POSSIBILITY FOR SLIGHTLY HIGHER SPEEDS. DO EXPECT MORE OF A WEST
NORTHWEST WIND ACROSS THE LAKE ON SUNDAY...AS A SECONDARY
TROUGH/FRONT MOVE SOUTHEAST THROUGH THE GREAT LAKES REGION.
RODRIGUEZ
&&
.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 UNTIL 1 PM SUNDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 1
PM SUNDAY.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
511 PM CDT SAT JUL 12 2014
.MESOSCALE DISCUSSION...
510 PM CDT
STORMS ARE INITIATING ACROSS SOUTHERN AND EASTERN IA AND HAVE
PROMPTED THE ISSUANCE OF A TORNADO WATCH THAT EXTENDS AS FAR EAST
AS NORTHWEST IL. LATEST HAND SURFACE ANALYSIS INDICATES A POOL OF
75+ DEW POINTS ACROSS SOUTHEAST IA INTO CENTRAL IL ADVANCING
NORTHWARD WITH MANY SURFACE OBS IN THIS AREA INDICATING
GUSTINESS. AT THE LEADING EDGE OF THIS A WARM FRONT WITH STRONG
MOISTURE CONVERGENCE IS INCHING NORTHWARD NEAR INTERSTATE 88
AHEAD OF A 1012MB SFC LOW IN CENTRAL IA. SUCH A SETUP OF A SLOWING
NORTHWARD-MOVING WARM FRONT AHEAD OF A NOT-TOO-STRONG LOW PRESSURE
WITH GOOD REPLENISHING MOISTURE REALLY SPELLS TROUBLE FOR HEAVY
RAINFALL TONIGHT WITHIN THE REGION. MOST FAVORED THIS EVE WOULD BE
ALONG AND IMMEDIATELY NORTH OF THIS WARM FRONTAL AXIS...SO THE
NORTHERN FORECAST AREA INCLUDING ROCKFORD. AS CONVECTION
EVOLVES/EXPANDS EASTWARD THROUGH MID-LATE EVENING...SOME
SOUTHWARD PROGRESSION IS THEN LIKELY INTO OVERNIGHT. SO THE ENTIRE
AREA REMAINS UNDER AN INCREASING RISK FOR HEAVY RAINFALL CAPABLE
OF FLASH FLOODING...WHICH OBSERVATIONAL TRENDS SUPPORT.
SEVERE WEATHER THREAT REMAINS AS MENTIONED IN PREV DISCUSSION.
MTF
&&
.DISCUSSION...
311 PM CDT
THIS AFTERNOON...
THE SURFACE LOW IS OVER NORTHERN MANITOBA AND THE UPPER LEVEL LOW IS
STACKED JUST ABOVE IT. STILL HAVE MOSTLY CLOUD SKIES WITH A FEW
BREAKS OF SUN AND WE ARE SLOWLY RECOVERING FROM THIS MORNING/S
CONVECTION. THE 18Z DVN SOUNDING FEATURED 1.7 INCHES OF PWAT AND
AROUND 1500 J/KG OF CAPE. THE SOUNDING ALSO HAD A STOUT CAP AT 850MB
WHICH MATCHES WELL WITH THE LATEST AMDAR SOUNDINGS. LAPSE RATES TO
950 MB WERE SURPRISINGLY STEEP GIVEN THE THICK CLOUD COVER. WITH THE
CAP IN PLACE AND SLOW RECOVERY NOT EXPECTING MUCH CONVECTIVE
ACTIVITY AHEAD OF THE MAIN LINE OF STORMS. IN GENERAL EXPECTING
CLOUDS TO CONTINUE THIN AND TEMPS RISE INTO THE MID 80S BY LATE THIS
AFTN. IT WILL CONTINUE TO BE MUGGY AS PWAT VALUES INCREASE TO
AROUND 2 INCHES.
THIS EVENING AND TONIGHT...
AN UPPER LEVEL SHORTWAVE CURRENTLY OVER IOWA WILL MOVE OVER THE CWA
THIS EVENING ADDING FORCING FOR STORMS. A SURFACE LOW IS OVER
NORTHERN MANITOBA AND ITS COLD FRONT STRETCHES FROM NORTHWEST
WISCONSIN THROUGH CENTRAL IOWA. A LINE OF STORMS WILL FORM ALONG
THE FRONT AND SLOWLY PUSH SOUTH THROUGH THE CWA THIS EVENING AND
OVERNIGHT. 850MB STEERING FLOW WILL BE WEST AT 30-40 KT AHEAD OF THE
LINE BUT ONLY AROUND 15 KT FROM THE NORTH BEHIND THE FRONT. TIMING
DIFFERS BETWEEN THE MODELS BUT THINKING A BLEND OF OUR LOCAL ARW AND
THE RAP LOOK REASONABLE. THE NAM LOOKS TOO FAST WHILE THE HRRR LOOKS
TOO SLOW.
THE LINE MAY PRODUCE SEVERE WIND GUSTS IN EXCESS OF 60 MPH...BUT THE
MAIN CONCERN WILL BE FLASH FLOODING. PWAT VALUES REMAIN HIGH AT
1.7-1.8 INCHES AND VALUES WILL INCREASE TO AROUND 2 INCHES BY THIS
EVENING. HAVE ISSUED A FLASH FLOOD WATCH FOR THE ENTIRE WARNING
AREA FOR THIS EVENING THROUGH TOMORROW MORNING. TOTAL RAINFALL FROM
THIS STORM WILL BE IN EXCESS OF 1 INCH. THE HIGHEST TOTALS WILL
LIKELY BE ALONG THE IL/WI STATE LINE WHERE RAINFALL TOTALS WILL
EASILY APPROACH 2 INCHES. IN ADDITION...SOME AREAS THIS MORNING
FROM COOK COUNTY SOUTH THROUGH PONTIAC AND GIBSON CITY SAW MULTIPLE
INCHES OF RAIN OVERNIGHT INTO THIS MORNING. THESE AREAS WILL BE THE
MOST SUSCEPTIBLE TO FLASH FLOODING AS WATER LEVELS ARE ALREADY
HIGH.
TEMPERATURES WILL QUICKLY FALL BEHIND THE LINE OF STORMS AND LOWS
WILL BE IN THE UPPER 60S TO LOWER 70S.
SUNDAY AND MONDAY...
THE UPPER LEVEL LOW SPLITS SUNDAY NIGHT AND THE FIRST TROUGH AXIS
MOVES THROUGH MONDAY NIGHT. AT THE SURFACE A SECOND COLD FRONT
MOVES THROUGH SUNDAY AND THEN STALLS OUT JUST SOUTH OF THE CWA
MONDAY MORNING. THE HIGHEST INSTABILITY VALUES WILL BE SOUTH OF I-80
SO ONLY HAVE A CHANCE OF STORMS SOUTH OF I-80. NOT EXPECTING MUCH IN
THE WAY OF PRECIP AT THIS TIME.
A BAND OF SHOWERS AND STORMS MAY FORM SUNDAY NIGHT FIRST ALONG THE
IL/WI STATE LINE AND THEN SPREAD SOUTH AS A VORTICITY STREAMER FROM
THE UPPER LEVEL LOW PUSHES SOUTH THROUGH THE REGION. THE SHOWERS
MAY PERSIST INTO LATE SUNDAY NIGHT AND BY THEN ONLY EXPECTING
SHOWERS. CONFIDENCE IS MEDIUM WITH THE STORMS DEVELOPING AND
COVERAGE.
YET ANOTHER COLD FRONT COMES THROUGH MONDAY AND HAVE A CHANCE OF
SHOWERS AND STORMS MONDAY AFTERNOON AND EVENING. THE BIGGER STORY
WILL BE THE COOL AIR THAT FOLLOWS THE COLD FRONT. HIGHS ON SUNDAY
WILL BE IN THE LOWER 80S WHILE MONDAY/S HIGHS WILL BE IN THE MID TO
UPPER 70S. MONDAY NIGHT LOOKS CRISP WITH LOWS IN THE LOWER 50S.
EXTENDED...TUESDAY THROUGH FRIDAY...
THE UPPER LEVEL TROUGH SLOWLY LIFTS NE THROUGH THURSDAY WHILE A
SURFACE HIGH BUILDS OVER THE REGION TUESDAY NIGHT. THE EXTENDED
LOOKS DRY WITH BELOW NORMAL TEMPERATURES.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* LOW CHANCE OF SHRA/TSRA BETWEEN 00Z AND 02Z...SHRA/TSRA EXPECTED
SOME TIME AROUND MID EVENING INTO EARLY OVERNIGHT. HEAVY
RAINFALL WITH IFR VISIBILITY AT TIMES BECOMING MORE LIKELY. WILL
LIKELY INCLUDE TEMPO IN 00Z TAFS FOR VISIBILITY OF 1 SM OR
POSSIBLY LOWER.
* CHANCE FOR MVFR CIGS TO LINGER INTO SUNDAY MORNING.
MTF/MDB
//DISCUSSION...UPDATED 20Z...
NO MAJOR CHANGES IN THINKING AT THIS POINT. CUMULUS IS STARTING TO
DEVELOP ALONG A NARROW LINE FROM SOUTHWEST IOWA NORTHEASTWARD UP
TOWARDS DBQ ALONG THE FRONTAL BOUNDARY THAT WILL IMPACT THE
TERMINALS THROUGH THE EVENING. EXPECT THAT THIS WILL EVOLVE INTO
THUNDERSTORMS OVER THE NEXT FEW HOURS WITH ACTIVITY POTENTIALLY
DEVELOPING INTO FAR NORTHWEST ILLINOIS...AND POSSIBLY RFD IN A FEW
HOURS. OVERALL TIMING SPECIFICS AT THE TERMINALS IS STILL SOMEWHAT
UNCERTAIN BUT DO NOT SEE MUCH TO SUPPORT ANY IMMEDIATE CHANGES.
OTHERWISE...MVFR CIGS HAVE BEEN SCATTERING THOUGH SOME BROKEN PATCH
MAY REMAIN ACROSS NORTH CENTRAL ILLINOIS.
FROM 18Z...
SOUTHWEST WINDS ARE STARTING TO INCREASE IN SPEED WITH GUSTS IN
THE 20-25 KT RANGE. CIGS ARE STARTING TO IMPROVE WITH MAINLY MVFR
IN PLACE. A LOOK OUT THE WINDOW AT THE OFFICE SHOWS STEADY
SCATTERING OF THE LOWEST CLOUDS WHICH SUPPORTS THE THINKING THAT
IMPROVEMENT TO VFR WILL OCCUR OVER THE NEXT FEW HOURS. FOCUS TURNS
TO TIMING OF SHRA/TSRA INTO THE EVENING. NOT MUCH IN THE WAY OF
FOCUS FOR DEVELOPMENT THROUGH MID AFTERNOON BUT FORCING WILL
INCREASE FAR NORTHWEST LATE THIS AFTERNOON. SOME SCATTERED
ACTIVITY IS POSSIBLE UP TOWARDS RFD BY THEN BUT THE FOCUS FOR THE
MOST WIDESPREAD DEVELOPMENT WILL BE ALONG A FRONTAL BOUNDARY FROM
SOUTHERN WISCONSIN WEST-SOUTHWEST INTO EASTERN IOWA. THIS ACTIVITY
WILL SAG SOUTHWARD THIS EVENING. TIMING IS STILL IN QUESTION SO
FURTHER ADJUSTMENTS MAY BE NEEDED BUT AT THIS POINT EARLY EVENING
IS FAVORED AT RFD WITH MID EVENING IN THE CHICAGO AREA AND
SLIGHTLY LATER AT GYY AS THINGS SAG SOUTHWARD. THE FRONT WILL BE
FAIRLY SLOW TO MOVE SO TRAINING OF STORMS ALONG THE FRONT IS
EXPECTED LEADING TO A FAIRLY LONG DURATION OF THUNDER. TORRENTIAL
RAINFALL MAY BRING VSBY DOWN BELOW 1SM BUT WILL HOLD OFF ON THIS
DETAIL IN THE TAF UNTIL IT BECOMES MORE CLEAR. WINDS MAY BE
ERRATIC OVERNIGHT BEHIND THE FRONT BUT TREND TO WEST THEN
NORTHWEST INTO SUNDAY MORNING. MVFR MAY LINGER BEHIND THE FRONT AS
WELL BUT VFR SHOULD BUILD IN.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* MEDIUM IN WINDS...BUT HIGH THEY WILL REMAIN FROM THE SOUTHWEST
THROUGH AT LEAST 01Z.
* HIGH THAT CHANCE FOR TSRA WILL WAIT UNTIL AFTER 00Z. HIGH THAT
TSRA WILL OCCUR TONIGHT...MEDIUM IN TIMING. HIGH THAT TEMPORARY
IFR VISIBILITY WILL OCCUR.
* MEDIUM-HIGH IN CIGS REMAINING VFR UNTIL TSRA.
MTF/MDB
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY-MONDAY...LOW CHANCES OF TSRA.
TUESDAY...SLIGHT CHANCE OF SHRA.
WEDNESDAY-THURSDAY...VFR LIKELY.
KMD
&&
.MARINE...
423 PM CDT
SOUTHERLY FLOW PERSISTING OVER THE ENTIRE LAKE THIS AFTERNOON AS
HIGH PRESSURE REMAINS SITUATED OVER THE ATLANTIC COAST...AND AS A
TROUGH OF LOW PRESSURE AND ASSOCIATED FRONTAL BOUNDARY ARE JUST
WEST OF THE LAKE. AS THESE SOUTHERLY WINDS BECOME MORE SOUTHWEST
AND THEN EVENTUALLY WEST TONIGHT WITH THE PASSAGE OF THIS
TROUGH...DO EXPECT SPEEDS TO REMAIN IN THE 10 TO 20 KT RANGE.
EXPECTED COMPLEX OF SHOWERS AND THUNDERSTORMS WILL LIKELY PROVIDE
ERRATIC WINDS LATER THIS EVENING AND OVERNIGHT...AS WELL AS THE
POSSIBILITY FOR SLIGHTLY HIGHER SPEEDS. DO EXPECT MORE OF A WEST
NORTHWEST WIND ACROSS THE LAKE ON SUNDAY...AS A SECONDARY
TROUGH/FRONT MOVE SOUTHEAST THROUGH THE GREAT LAKES REGION.
RODRIGUEZ
&&
.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 UNTIL 1 PM SUNDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 1
PM SUNDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
424 PM CDT SAT JUL 12 2014
.DISCUSSION...
311 PM CDT
THIS AFTERNOON...
THE SURFACE LOW IS OVER NORTHERN MANITOBA AND THE UPPER LEVEL LOW IS
STACKED JUST ABOVE IT. STILL HAVE MOSTLY CLOUD SKIES WITH A FEW
BREAKS OF SUN AND WE ARE SLOWLY RECOVERING FROM THIS MORNING/S
CONVECTION. THE 18Z DVN SOUNDING FEATURED 1.7 INCHES OF PWAT AND
AROUND 1500 J/KG OF CAPE. THE SOUNDING ALSO HAD A STOUT CAP AT 850MB
WHICH MATCHES WELL WITH THE LATEST AMDAR SOUNDINGS. LAPSE RATES TO
950 MB WERE SURPRISINGLY STEEP GIVEN THE THICK CLOUD COVER. WITH THE
CAP IN PLACE AND SLOW RECOVERY NOT EXPECTING MUCH CONVECTIVE
ACTIVITY AHEAD OF THE MAIN LINE OF STORMS. IN GENERAL EXPECTING
CLOUDS TO CONTINUE THIN AND TEMPS RISE INTO THE MID 80S BY LATE THIS
AFTN. IT WILL CONTINUE TO BE MUGGY AS PWAT VALUES INCREASE TO
AROUND 2 INCHES.
THIS EVENING AND TONIGHT...
AN UPPER LEVEL SHORTWAVE CURRENTLY OVER IOWA WILL MOVE OVER THE CWA
THIS EVENING ADDING FORCING FOR STORMS. A SURFACE LOW IS OVER
NORTHERN MANITOBA AND ITS COLD FRONT STRETCHES FROM NORTHWEST
WISCONSIN THROUGH CENTRAL IOWA. A LINE OF STORMS WILL FORM ALONG
THE FRONT AND SLOWLY PUSH SOUTH THROUGH THE CWA THIS EVENING AND
OVERNIGHT. 850MB STEERING FLOW WILL BE WEST AT 30-40 KT AHEAD OF THE
LINE BUT ONLY AROUND 15 KT FROM THE NORTH BEHIND THE FRONT. TIMING
DIFFERS BETWEEN THE MODELS BUT THINKING A BLEND OF OUR LOCAL ARW AND
THE RAP LOOK REASONABLE. THE NAM LOOKS TOO FAST WHILE THE HRRR LOOKS
TOO SLOW.
THE LINE MAY PRODUCE SEVERE WIND GUSTS IN EXCESS OF 60 MPH...BUT THE
MAIN CONCERN WILL BE FLASH FLOODING. PWAT VALUES REMAIN HIGH AT
1.7-1.8 INCHES AND VALUES WILL INCREASE TO AROUND 2 INCHES BY THIS
EVENING. HAVE ISSUED A FLASH FLOOD WATCH FOR THE ENTIRE WARNING
AREA FOR THIS EVENING THROUGH TOMORROW MORNING. TOTAL RAINFALL FROM
THIS STORM WILL BE IN EXCESS OF 1 INCH. THE HIGHEST TOTALS WILL
LIKELY BE ALONG THE IL/WI STATE LINE WHERE RAINFALL TOTALS WILL
EASILY APPROACH 2 INCHES. IN ADDITION...SOME AREAS THIS MORNING
FROM COOK COUNTY SOUTH THROUGH PONTIAC AND GIBSON CITY SAW MULTIPLE
INCHES OF RAIN OVERNIGHT INTO THIS MORNING. THESE AREAS WILL BE THE
MOST SUSCEPTIBLE TO FLASH FLOODING AS WATER LEVELS ARE ALREADY
HIGH.
TEMPERATURES WILL QUICKLY FALL BEHIND THE LINE OF STORMS AND LOWS
WILL BE IN THE UPPER 60S TO LOWER 70S.
SUNDAY AND MONDAY...
THE UPPER LEVEL LOW SPLITS SUNDAY NIGHT AND THE FIRST TROUGH AXIS
MOVES THROUGH MONDAY NIGHT. AT THE SURFACE A SECOND COLD FRONT
MOVES THROUGH SUNDAY AND THEN STALLS OUT JUST SOUTH OF THE CWA
MONDAY MORNING. THE HIGHEST INSTABILITY VALUES WILL BE SOUTH OF I-80
SO ONLY HAVE A CHANCE OF STORMS SOUTH OF I-80. NOT EXPECTING MUCH IN
THE WAY OF PRECIP AT THIS TIME.
A BAND OF SHOWERS AND STORMS MAY FORM SUNDAY NIGHT FIRST ALONG THE
IL/WI STATE LINE AND THEN SPREAD SOUTH AS A VORTICITY STREAMER FROM
THE UPPER LEVEL LOW PUSHES SOUTH THROUGH THE REGION. THE SHOWERS
MAY PERSIST INTO LATE SUNDAY NIGHT AND BY THEN ONLY EXPECTING
SHOWERS. CONFIDENCE IS MEDIUM WITH THE STORMS DEVELOPING AND
COVERAGE.
YET ANOTHER COLD FRONT COMES THROUGH MONDAY AND HAVE A CHANCE OF
SHOWERS AND STORMS MONDAY AFTERNOON AND EVENING. THE BIGGER STORY
WILL BE THE COOL AIR THAT FOLLOWS THE COLD FRONT. HIGHS ON SUNDAY
WILL BE IN THE LOWER 80S WHILE MONDAY/S HIGHS WILL BE IN THE MID TO
UPPER 70S. MONDAY NIGHT LOOKS CRISP WITH LOWS IN THE LOWER 50S.
EXTENDED...TUESDAY THROUGH FRIDAY...
THE UPPER LEVEL TROUGH SLOWLY LIFTS NE THROUGH THURSDAY WHILE A
SURFACE HIGH BUILDS OVER THE REGION TUESDAY NIGHT. THE EXTENDED
LOOKS DRY WITH BELOW NORMAL TEMPERATURES.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* BREEZY SOUTHWEST WINDS GUSTING 20-25 KT THROUGH AFTERNOON.
* LOW CHANCE OF SHRA/TSRA LATE AFTERNOON INTO EARLY
EVENING...SHRA/TSRA EXPECTED SOME TIME AROUND MID EVENING. GUSTY
WINDS AND HEAVY RAINFALL POSSIBLE.
* MVFR CIGS EXPECTED TO SCATTER TO VFR MID AFTERNOON.
MDB
//DISCUSSION...UPDATED 20Z...
NO MAJOR CHANGES IN THINKING AT THIS POINT. CUMULUS IS STARTING TO
DEVELOP ALONG A NARROW LINE FROM SOUTHWEST IOWA NORTHEASTWARD UP
TOWARDS DBQ ALONG THE FRONTAL BOUNDARY THAT WILL IMPACT THE
TERMINALS THROUGH THE EVENING. EXPECT THAT THIS WILL EVOLVE INTO
THUNDERSTORMS OVER THE NEXT FEW HOURS WITH ACTIVITY POTENTIALLY
DEVELOPING INTO FAR NORTHWEST ILLINOIS...AND POSSIBLY RFD IN A FEW
HOURS. OVERALL TIMING SPECIFICS AT THE TERMINALS IS STILL SOMEWHAT
UNCERTAIN BUT DO NOT SEE MUCH TO SUPPORT ANY IMMEDIATE CHANGES.
OTHERWISE...MVFR CIGS HAVE BEEN SCATTERING THOUGH SOME BROKEN PATCH
MAY REMAIN ACROSS NORTH CENTRAL ILLINOIS.
FROM 18Z...
SOUTHWEST WINDS ARE STARTING TO INCREASE IN SPEED WITH GUSTS IN
THE 20-25 KT RANGE. CIGS ARE STARTING TO IMPROVE WITH MAINLY MVFR
IN PLACE. A LOOK OUT THE WINDOW AT THE OFFICE SHOWS STEADY
SCATTERING OF THE LOWEST CLOUDS WHICH SUPPORTS THE THINKING THAT
IMPROVEMENT TO VFR WILL OCCUR OVER THE NEXT FEW HOURS. FOCUS TURNS
TO TIMING OF SHRA/TSRA INTO THE EVENING. NOT MUCH IN THE WAY OF
FOCUS FOR DEVELOPMENT THROUGH MID AFTERNOON BUT FORCING WILL
INCREASE FAR NORTHWEST LATE THIS AFTERNOON. SOME SCATTERED
ACTIVITY IS POSSIBLE UP TOWARDS RFD BY THEN BUT THE FOCUS FOR THE
MOST WIDESPREAD DEVELOPMENT WILL BE ALONG A FRONTAL BOUNDARY FROM
SOUTHERN WISCONSIN WEST-SOUTHWEST INTO EASTERN IOWA. THIS ACTIVITY
WILL SAG SOUTHWARD THIS EVENING. TIMING IS STILL IN QUESTION SO
FURTHER ADJUSTMENTS MAY BE NEEDED BUT AT THIS POINT EARLY EVENING
IS FAVORED AT RFD WITH MID EVENING IN THE CHICAGO AREA AND
SLIGHTLY LATER AT GYY AS THINGS SAG SOUTHWARD. THE FRONT WILL BE
FAIRLY SLOW TO MOVE SO TRAINING OF STORMS ALONG THE FRONT IS
EXPECTED LEADING TO A FAIRLY LONG DURATION OF THUNDER. TORRENTIAL
RAINFALL MAY BRING VSBY DOWN BELOW 1SM BUT WILL HOLD OFF ON THIS
DETAIL IN THE TAF UNTIL IT BECOMES MORE CLEAR. WINDS MAY BE
ERRATIC OVERNIGHT BEHIND THE FRONT BUT TREND TO WEST THEN
NORTHWEST INTO SUNDAY MORNING. MVFR MAY LINGER BEHIND THE FRONT AS
WELL BUT VFR SHOULD BUILD IN.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN WINDS.
* HIGH CONFIDENCE THAT CHANCE FOR SHRA/TSRA IS LOW LATER THIS
AFTERNOON AND SHRA/TSRA IS LIKELY THIS EVENING. MEDIUM
CONFIDENCE IN TIMING THIS EVENING.
* MEDIUM-HIGH CONFIDENCE IN MVFR IMPROVING TO VFR THIS AFTERNOON.
LOW-MEDIUM CONFIDENCE IN TIMING.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY-MONDAY...LOW CHANCES OF TSRA.
TUESDAY...SLIGHT CHANCE OF SHRA.
WEDNESDAY-THURSDAY...VFR LIKELY.
KMD
&&
.MARINE...
423 PM CDT
SOUTHERLY FLOW PERSISTING OVER THE ENTIRE LAKE THIS AFTERNOON AS
HIGH PRESSURE REMAINS SITUATED OVER THE ATLANTIC COAST...AND AS A
TROUGH OF LOW PRESSURE AND ASSOCIATED FRONTAL BOUNDARY ARE JUST
WEST OF THE LAKE. AS THESE SOUTHERLY WINDS BECOME MORE SOUTHWEST
AND THEN EVENTUALLY WEST TONIGHT WITH THE PASSAGE OF THIS
TROUGH...DO EXPECT SPEEDS TO REMAIN IN THE 10 TO 20 KT RANGE.
EXPECTED COMPLEX OF SHOWERS AND THUNDERSTORMS WILL LIKELY PROVIDE
ERRATIC WINDS LATER THIS EVENING AND OVERNIGHT...AS WELL AS THE
POSSIBILITY FOR SLIGHTLY HIGHER SPEEDS. DO EXPECT MORE OF A WEST
NORTHWEST WIND ACROSS THE LAKE ON SUNDAY...AS A SECONDARY
TROUGH/FRONT MOVE SOUTHEAST THROUGH THE GREAT LAKES REGION.
RODRIGUEZ
&&
.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 UNTIL 1 PM SUNDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 1
PM SUNDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
312 PM CDT SAT JUL 12 2014
.DISCUSSION...
311 PM CDT
THIS AFTERNOON...
THE SURFACE LOW IS OVER NORTHERN MANITOBA AND THE UPPER LEVEL LOW IS
STACKED JUST ABOVE IT. STILL HAVE MOSTLY CLOUD SKIES WITH A FEW
BREAKS OF SUN AND WE ARE SLOWLY RECOVERING FROM THIS MORNING/S
CONVECTION. THE 18Z DVN SOUNDING FEATURED 1.7 INCHES OF PWAT AND
AROUND 1500 J/KG OF CAPE. THE SOUNDING ALSO HAD A STOUT CAP AT 850MB
WHICH MATCHES WELL WITH THE LATEST AMDAR SOUNDINGS. LAPSE RATES TO
950 MB WERE SURPRISINGLY STEEP GIVEN THE THICK CLOUD COVER. WITH THE
CAP IN PLACE AND SLOW RECOVERY NOT EXPECTING MUCH CONVECTIVE
ACTIVITY AHEAD OF THE MAIN LINE OF STORMS. IN GENERAL EXPECTING
CLOUDS TO CONTINUE THIN AND TEMPS RISE INTO THE MID 80S BY LATE THIS
AFTN. IT WILL CONTINUE TO BE MUGGY AS PWAT VALUES INCREASE TO
AROUND 2 INCHES.
THIS EVENING AND TONIGHT...
AN UPPER LEVEL SHORTWAVE CURRENTLY OVER IOWA WILL MOVE OVER THE CWA
THIS EVENING ADDING FORCING FOR STORMS. A SURFACE LOW IS OVER
NORTHERN MANITOBA AND ITS COLD FRONT STRETCHES FROM NORTHWEST
WISCONSIN THROUGH CENTRAL IOWA. A LINE OF STORMS WILL FORM ALONG
THE FRONT AND SLOWLY PUSH SOUTH THROUGH THE CWA THIS EVENING AND
OVERNIGHT. 850MB STEERING FLOW WILL BE WEST AT 30-40 KT AHEAD OF THE
LINE BUT ONLY AROUND 15 KT FROM THE NORTH BEHIND THE FRONT. TIMING
DIFFERS BETWEEN THE MODELS BUT THINKING A BLEND OF OUR LOCAL ARW AND
THE RAP LOOK REASONABLE. THE NAM LOOKS TOO FAST WHILE THE HRRR LOOKS
TOO SLOW.
THE LINE MAY PRODUCE SEVERE WIND GUSTS IN EXCESS OF 60 MPH...BUT THE
MAIN CONCERN WILL BE FLASH FLOODING. PWAT VALUES REMAIN HIGH AT
1.7-1.8 INCHES AND VALUES WILL INCREASE TO AROUND 2 INCHES BY THIS
EVENING. HAVE ISSUED A FLASH FLOOD WATCH FOR THE ENTIRE WARNING
AREA FOR THIS EVENING THROUGH TOMORROW MORNING. TOTAL RAINFALL FROM
THIS STORM WILL BE IN EXCESS OF 1 INCH. THE HIGHEST TOTALS WILL
LIKELY BE ALONG THE IL/WI STATE LINE WHERE RAINFALL TOTALS WILL
EASILY APPROACH 2 INCHES. IN ADDITION...SOME AREAS THIS MORNING
FROM COOK COUNTY SOUTH THROUGH PONTIAC AND GIBSON CITY SAW MULTIPLE
INCHES OF RAIN OVERNIGHT INTO THIS MORNING. THESE AREAS WILL BE THE
MOST SUSCEPTIBLE TO FLASH FLOODING AS WATER LEVELS ARE ALREADY
HIGH.
TEMPERATURES WILL QUICKLY FALL BEHIND THE LINE OF STORMS AND LOWS
WILL BE IN THE UPPER 60S TO LOWER 70S.
SUNDAY AND MONDAY...
THE UPPER LEVEL LOW SPLITS SUNDAY NIGHT AND THE FIRST TROUGH AXIS
MOVES THROUGH MONDAY NIGHT. AT THE SURFACE A SECOND COLD FRONT
MOVES THROUGH SUNDAY AND THEN STALLS OUT JUST SOUTH OF THE CWA
MONDAY MORNING. THE HIGHEST INSTABILITY VALUES WILL BE SOUTH OF I-80
SO ONLY HAVE A CHANCE OF STORMS SOUTH OF I-80. NOT EXPECTING MUCH IN
THE WAY OF PRECIP AT THIS TIME.
A BAND OF SHOWERS AND STORMS MAY FORM SUNDAY NIGHT FIRST ALONG THE
IL/WI STATE LINE AND THEN SPREAD SOUTH AS A VORTICITY STREAMER FROM
THE UPPER LEVEL LOW PUSHES SOUTH THROUGH THE REGION. THE SHOWERS
MAY PERSIST INTO LATE SUNDAY NIGHT AND BY THEN ONLY EXPECTING
SHOWERS. CONFIDENCE IS MEDIUM WITH THE STORMS DEVELOPING AND
COVERAGE.
YET ANOTHER COLD FRONT COMES THROUGH MONDAY AND HAVE A CHANCE OF
SHOWERS AND STORMS MONDAY AFTERNOON AND EVENING. THE BIGGER STORY
WILL BE THE COOL AIR THAT FOLLOWS THE COLD FRONT. HIGHS ON SUNDAY
WILL BE IN THE LOWER 80S WHILE MONDAY/S HIGHS WILL BE IN THE MID TO
UPPER 70S. MONDAY NIGHT LOOKS CRISP WITH LOWS IN THE LOWER 50S.
EXTENDED...TUESDAY THROUGH FRIDAY...
THE UPPER LEVEL TROUGH SLOWLY LIFTS NE THROUGH THURSDAY WHILE A
SURFACE HIGH BUILDS OVER THE REGION TUESDAY NIGHT. THE EXTENDED
LOOKS DRY WITH BELOW NORMAL TEMPERATURES.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* BREEZY SOUTHWEST WINDS GUSTING 20-25 KT THROUGH AFTERNOON.
* LOW CHANCE OF SHRA/TSRA LATE AFTERNOON INTO EARLY
EVENING...SHRA/TSRA EXPECTED SOME TIME AROUND MID EVENING. GUSTY
WINDS AND HEAVY RAINFALL POSSIBLE.
* MVFR CIGS EXPECTED TO SCATTER TO VFR MID AFTERNOON.
MDB
//DISCUSSION...UPDATED 20Z...
NO MAJOR CHANGES IN THINKING AT THIS POINT. CUMULUS IS STARTING TO
DEVELOP ALONG A NARROW LINE FROM SOUTHWEST IOWA NORTHEASTWARD UP
TOWARDS DBQ ALONG THE FRONTAL BOUNDARY THAT WILL IMPACT THE
TERMINALS THROUGH THE EVENING. EXPECT THAT THIS WILL EVOLVE INTO
THUNDERSTORMS OVER THE NEXT FEW HOURS WITH ACTIVITY POTENTIALLY
DEVELOPING INTO FAR NORTHWEST ILLINOIS...AND POSSIBLY RFD IN A FEW
HOURS. OVERALL TIMING SPECIFICS AT THE TERMINALS IS STILL SOMEWHAT
UNCERTAIN BUT DO NOT SEE MUCH TO SUPPORT ANY IMMEDIATE CHANGES.
OTHERWISE...MVFR CIGS HAVE BEEN SCATTERING THOUGH SOME BROKEN PATCH
MAY REMAIN ACROSS NORTH CENTRAL ILLINOIS.
FROM 18Z...
SOUTHWEST WINDS ARE STARTING TO INCREASE IN SPEED WITH GUSTS IN
THE 20-25 KT RANGE. CIGS ARE STARTING TO IMPROVE WITH MAINLY MVFR
IN PLACE. A LOOK OUT THE WINDOW AT THE OFFICE SHOWS STEADY
SCATTERING OF THE LOWEST CLOUDS WHICH SUPPORTS THE THINKING THAT
IMPROVEMENT TO VFR WILL OCCUR OVER THE NEXT FEW HOURS. FOCUS TURNS
TO TIMING OF SHRA/TSRA INTO THE EVENING. NOT MUCH IN THE WAY OF
FOCUS FOR DEVELOPMENT THROUGH MID AFTERNOON BUT FORCING WILL
INCREASE FAR NORTHWEST LATE THIS AFTERNOON. SOME SCATTERED
ACTIVITY IS POSSIBLE UP TOWARDS RFD BY THEN BUT THE FOCUS FOR THE
MOST WIDESPREAD DEVELOPMENT WILL BE ALONG A FRONTAL BOUNDARY FROM
SOUTHERN WISCONSIN WEST-SOUTHWEST INTO EASTERN IOWA. THIS ACTIVITY
WILL SAG SOUTHWARD THIS EVENING. TIMING IS STILL IN QUESTION SO
FURTHER ADJUSTMENTS MAY BE NEEDED BUT AT THIS POINT EARLY EVENING
IS FAVORED AT RFD WITH MID EVENING IN THE CHICAGO AREA AND
SLIGHTLY LATER AT GYY AS THINGS SAG SOUTHWARD. THE FRONT WILL BE
FAIRLY SLOW TO MOVE SO TRAINING OF STORMS ALONG THE FRONT IS
EXPECTED LEADING TO A FAIRLY LONG DURATION OF THUNDER. TORRENTIAL
RAINFALL MAY BRING VSBY DOWN BELOW 1SM BUT WILL HOLD OFF ON THIS
DETAIL IN THE TAF UNTIL IT BECOMES MORE CLEAR. WINDS MAY BE
ERRATIC OVERNIGHT BEHIND THE FRONT BUT TREND TO WEST THEN
NORTHWEST INTO SUNDAY MORNING. MVFR MAY LINGER BEHIND THE FRONT AS
WELL BUT VFR SHOULD BUILD IN.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN WINDS.
* HIGH CONFIDENCE THAT CHANCE FOR SHRA/TSRA IS LOW LATER THIS
AFTERNOON AND SHRA/TSRA IS LIKELY THIS EVENING. MEDIUM
CONFIDENCE IN TIMING THIS EVENING.
* MEDIUM-HIGH CONFIDENCE IN MVFR IMPROVING TO VFR THIS AFTERNOON.
LOW-MEDIUM CONFIDENCE IN TIMING.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY-MONDAY...LOW CHANCES OF TSRA.
TUESDAY...SLIGHT CHANCE OF SHRA.
WEDNESDAY-THURSDAY...VFR LIKELY.
KMD
&&
.MARINE...
244 AM CDT
STILL SEEING GUSTS TO NEAR 20 KT ON THE NORTHERN HALF OF THE
LAKE...BUT DO EXPECT THE PRESSURE GRADIENT TO RELAX TONIGHT INTO
SATURDAY AS HIGH PRESSURE ALONG THE ATLANTIC COAST CONTINUES EAST.
A TROUGH OF LOW PRESS SURE AND FRONTAL BOUNDARY WILL CROSS THE LAKE
ON SATURDAY NIGHT. CONFIDENCE IS LOWER WITH REGARDS TO OVERALL
WIND DIRECTION AND SPEEDS SATURDAY EVENING INTO SATURDAY NIGHT AS
PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED ALONG THIS
FRONTAL BOUNDARY. A SERIES OF WEAK LOW PRESSURE SYSTEMS AND
ASSOCIATED COLD FRONTS WILL THEN PASS THROUGH THE LAKE THROUGH
MONDAY WHILE HIGH PRESSURE BUILDS INTO THE NORTHERN CENTRAL
PLAINS. WINDS SHIFT TO WEST- NORTHWEST BEHIND THE STRONGER COLD
FRONTAL PUSH MONDAY NIGHT AND REACH 20 KT OR POSSIBLY HIGHER
TUESDAY.
KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
309 PM CDT SAT JUL 12 2014
.DISCUSSION...
300 PM CDT
THE SHORT TERM DISCUSSION WILL BE POSTED SHORTLY.
TONIGHT...
AN UPPER LEVEL SHORTWAVE CURRENTLY OVER IOWA WILL MOVE OVER THE CWA
THIS EVENING ADDING FORCING FOR STORMS. A SURFACE LOW IS OVER
NORTHERN MANITOBA AND ITS COLD FRONT STRETCHES FROM NORTHWEST
WISCONSIN THROUGH CENTRAL IOWA. A LINE OF STORMS WILL FORM ALONG
THE FRONT AND SLOWLY PUSH SOUTH THROUGH THE CWA THIS EVENING AND
OVERNIGHT. 850MB STEERING FLOW WILL BE WEST AT 30-40 KT AHEAD OF THE
LINE BUT ONLY AROUND 15 KT FROM THE NORTH BEHIND THE FRONT. TIMING
DIFFERS BETWEEN THE MODELS BUT THINKING A BLEND OF OUR LOCAL ARW AND
THE RAP LOOK REASONABLE. THE NAM LOOKS TOO FAST WHILE THE HRRR LOOKS
TOO SLOW.
THE LINE MAY PRODUCE SEVERE WIND GUSTS IN EXCESS OF 60 MPH...BUT THE
MAIN CONCERN WILL BE FLASH FLOODING. PWAT VALUES REMAIN HIGH AT
1.7-1.8 INCHES AND VALUES WILL INCREASE TO AROUND 2 INCHES BY THIS
EVENING. HAVE ISSUED A FLASH FLOOD WATCH FOR THE ENTIRE WARNING
AREA FOR THIS EVENING THROUGH TOMORROW MORNING. TOTAL RAINFALL FROM
THIS STORM WILL BE IN EXCESS OF 1 INCH. THE HIGHEST TOTALS WILL
LIKELY BE ALONG THE IL/WI STATE LINE WHERE RAINFALL TOTALS WILL
EASILY APPROACH 2 INCHES. IN ADDITION...SOME AREAS THIS MORNING
FROM COOK COUNTY SOUTH THROUGH PONTIAC AND GIBSON CITY SAW MULTIPLE
INCHES OF RAIN OVERNIGHT INTO THIS MORNING. THESE AREAS WILL BE THE
MOST SUSCEPTIBLE TO FLASH FLOODING AS WATER LEVELS ARE ALREADY
HIGH.
TEMPERATURES WILL QUICKLY FALL BEHIND THE LINE OF STORMS AND LOWS
WILL BE IN THE UPPER 60S TO LOWER 70S.
SUNDAY AND MONDAY...
THE UPPER LEVEL LOW SPLITS SUNDAY NIGHT AND THE FIRST TROUGH AXIS
MOVES THROUGH MONDAY NIGHT. AT THE SURFACE A SECOND COLD FRONT
MOVES THROUGH SUNDAY AND THEN STALLS OUT JUST SOUTH OF THE CWA
MONDAY MORNING. THE HIGHEST INSTABILITY VALUES WILL BE SOUTH OF I-80
SO ONLY HAVE A CHANCE OF STORMS SOUTH OF I-80. NOT EXPECTING MUCH IN
THE WAY OF PRECIP AT THIS TIME.
A BAND OF SHOWERS AND STORMS MAY FORM SUNDAY NIGHT FIRST ALONG THE
IL/WI STATE LINE AND THEN SPREAD SOUTH AS A VORTICITY STREAMER FROM
THE UPPER LEVEL LOW PUSHES SOUTH THROUGH THE REGION. THE SHOWERS
MAY PERSIST INTO LATE SUNDAY NIGHT AND BY THEN ONLY EXPECTING
SHOWERS. CONFIDENCE IS MEDIUM WITH THE STORMS DEVELOPING AND
COVERAGE.
YET ANOTHER COLD FRONT COMES THROUGH MONDAY AND HAVE A CHANCE OF
SHOWERS AND STORMS MONDAY AFTERNOON AND EVENING. THE BIGGER STORY
WILL BE THE COOL AIR THAT FOLLOWS THE COLD FRONT. HIGHS ON SUNDAY
WILL BE IN THE LOWER 80S WHILE MONDAY/S HIGHS WILL BE IN THE MID TO
UPPER 70S. MONDAY NIGHT LOOKS CRISP WITH LOWS IN THE LOWER 50S.
EXTENDED...TUESDAY THROUGH FRIDAY...
THE UPPER LEVEL TROUGH SLOWLY LIFTS NE THROUGH THURSDAY WHILE A
SURFACE HIGH BUILDS OVER THE REGION TUESDAY NIGHT. THE EXTENDED
LOOKS DRY WITH BELOW NORMAL TEMPERATURES.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* BREEZY SOUTHWEST WINDS GUSTING 20-25 KT THROUGH AFTERNOON.
* LOW CHANCE OF SHRA/TSRA LATE AFTERNOON INTO EARLY
EVENING...SHRA/TSRA EXPECTED SOME TIME AROUND MID EVENING. GUSTY
WINDS AND HEAVY RAINFALL POSSIBLE.
* MVFR CIGS EXPECTED TO SCATTER TO VFR MID AFTERNOON.
MDB
//DISCUSSION...UPDATED 20Z...
NO MAJOR CHANGES IN THINKING AT THIS POINT. CUMULUS IS STARTING TO
DEVELOP ALONG A NARROW LINE FROM SOUTHWEST IOWA NORTHEASTWARD UP
TOWARDS DBQ ALONG THE FRONTAL BOUNDARY THAT WILL IMPACT THE
TERMINALS THROUGH THE EVENING. EXPECT THAT THIS WILL EVOLVE INTO
THUNDERSTORMS OVER THE NEXT FEW HOURS WITH ACTIVITY POTENTIALLY
DEVELOPING INTO FAR NORTHWEST ILLINOIS...AND POSSIBLY RFD IN A FEW
HOURS. OVERALL TIMING SPECIFICS AT THE TERMINALS IS STILL SOMEWHAT
UNCERTAIN BUT DO NOT SEE MUCH TO SUPPORT ANY IMMEDIATE CHANGES.
OTHERWISE...MVFR CIGS HAVE BEEN SCATTERING THOUGH SOME BROKEN PATCH
MAY REMAIN ACROSS NORTH CENTRAL ILLINOIS.
FROM 18Z...
SOUTHWEST WINDS ARE STARTING TO INCREASE IN SPEED WITH GUSTS IN
THE 20-25 KT RANGE. CIGS ARE STARTING TO IMPROVE WITH MAINLY MVFR
IN PLACE. A LOOK OUT THE WINDOW AT THE OFFICE SHOWS STEADY
SCATTERING OF THE LOWEST CLOUDS WHICH SUPPORTS THE THINKING THAT
IMPROVEMENT TO VFR WILL OCCUR OVER THE NEXT FEW HOURS. FOCUS TURNS
TO TIMING OF SHRA/TSRA INTO THE EVENING. NOT MUCH IN THE WAY OF
FOCUS FOR DEVELOPMENT THROUGH MID AFTERNOON BUT FORCING WILL
INCREASE FAR NORTHWEST LATE THIS AFTERNOON. SOME SCATTERED
ACTIVITY IS POSSIBLE UP TOWARDS RFD BY THEN BUT THE FOCUS FOR THE
MOST WIDESPREAD DEVELOPMENT WILL BE ALONG A FRONTAL BOUNDARY FROM
SOUTHERN WISCONSIN WEST-SOUTHWEST INTO EASTERN IOWA. THIS ACTIVITY
WILL SAG SOUTHWARD THIS EVENING. TIMING IS STILL IN QUESTION SO
FURTHER ADJUSTMENTS MAY BE NEEDED BUT AT THIS POINT EARLY EVENING
IS FAVORED AT RFD WITH MID EVENING IN THE CHICAGO AREA AND
SLIGHTLY LATER AT GYY AS THINGS SAG SOUTHWARD. THE FRONT WILL BE
FAIRLY SLOW TO MOVE SO TRAINING OF STORMS ALONG THE FRONT IS
EXPECTED LEADING TO A FAIRLY LONG DURATION OF THUNDER. TORRENTIAL
RAINFALL MAY BRING VSBY DOWN BELOW 1SM BUT WILL HOLD OFF ON THIS
DETAIL IN THE TAF UNTIL IT BECOMES MORE CLEAR. WINDS MAY BE
ERRATIC OVERNIGHT BEHIND THE FRONT BUT TREND TO WEST THEN
NORTHWEST INTO SUNDAY MORNING. MVFR MAY LINGER BEHIND THE FRONT AS
WELL BUT VFR SHOULD BUILD IN.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN WINDS.
* HIGH CONFIDENCE THAT CHANCE FOR SHRA/TSRA IS LOW LATER THIS
AFTERNOON AND SHRA/TSRA IS LIKELY THIS EVENING. MEDIUM
CONFIDENCE IN TIMING THIS EVENING.
* MEDIUM-HIGH CONFIDENCE IN MVFR IMPROVING TO VFR THIS AFTERNOON.
LOW-MEDIUM CONFIDENCE IN TIMING.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY-MONDAY...LOW CHANCES OF TSRA.
TUESDAY...SLIGHT CHANCE OF SHRA.
WEDNESDAY-THURSDAY...VFR LIKELY.
KMD
&&
.MARINE...
244 AM CDT
STILL SEEING GUSTS TO NEAR 20 KT ON THE NORTHERN HALF OF THE
LAKE...BUT DO EXPECT THE PRESSURE GRADIENT TO RELAX TONIGHT INTO
SATURDAY AS HIGH PRESSURE ALONG THE ATLANTIC COAST CONTINUES EAST.
A TROUGH OF LOW PRESS SURE AND FRONTAL BOUNDARY WILL CROSS THE LAKE
ON SATURDAY NIGHT. CONFIDENCE IS LOWER WITH REGARDS TO OVERALL
WIND DIRECTION AND SPEEDS SATURDAY EVENING INTO SATURDAY NIGHT AS
PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED ALONG THIS
FRONTAL BOUNDARY. A SERIES OF WEAK LOW PRESSURE SYSTEMS AND
ASSOCIATED COLD FRONTS WILL THEN PASS THROUGH THE LAKE THROUGH
MONDAY WHILE HIGH PRESSURE BUILDS INTO THE NORTHERN CENTRAL
PLAINS. WINDS SHIFT TO WEST- NORTHWEST BEHIND THE STRONGER COLD
FRONTAL PUSH MONDAY NIGHT AND REACH 20 KT OR POSSIBLY HIGHER
TUESDAY.
KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
301 PM CDT SAT JUL 12 2014
.DISCUSSION...
300 PM CDT
THE SHORT TERM DISCUSSION WILL BE POSTED SHORTLY.
TONIGHT...
AN UPPER LEVEL SHORTWAVE CURRENTLY OVER IOWA WILL MOVE OVER THE CWA
THIS EVENING ADDING FORCING FOR STORMS. A SURFACE LOW IS OVER
NORTHERN MANITOBA AND ITS COLD FRONT STRETCHES FROM NORTHWEST
WISCONSIN THROUGH CENTRAL IOWA. A LINE OF STORMS WILL FORM ALONG
THE FRONT AND SLOWLY PUSH SOUTH THROUGH THE CWA THIS EVENING AND
OVERNIGHT. 850MB STEERING FLOW WILL BE WEST AT 30-40 KT AHEAD OF THE
LINE BUT ONLY AROUND 15 KT FROM THE NORTH BEHIND THE FRONT. TIMING
DIFFERS BETWEEN THE MODELS BUT THINKING A BLEND OF OUR LOCAL ARW AND
THE RAP LOOK REASONABLE. THE NAM LOOKS TOO FAST WHILE THE HRRR LOOKS
TOO SLOW.
THE LINE MAY PRODUCE SEVERE WIND GUSTS IN EXCESS OF 60 MPH...BUT THE
MAIN CONCERN WILL BE FLASH FLOODING. PWAT VALUES REMAIN HIGH AT
1.7-1.8 INCHES AND VALUES WILL INCREASE TO AROUND 2 INCHES BY THIS
EVENING. HAVE ISSUED A FLASH FLOOD WATCH FOR THE ENTIRE WARNING
AREA FOR THIS EVENING THROUGH TOMORROW MORNING. TOTAL RAINFALL FROM
THIS STORM WILL BE IN EXCESS OF 1 INCH. THE HIGHEST TOTALS WILL
LIKELY BE ALONG THE IL/WI STATE LINE WHERE RAINFALL TOTALS WILL
EASILY APPROACH 2 INCHES. IN ADDITION...SOME AREAS THIS MORNING
FROM COOK COUNTY SOUTH THROUGH PONTIAC AND GIBSON CITY SAW MULTIPLE
INCHES OF RAIN OVERNIGHT INTO THIS MORNING. THESE AREAS WILL BE THE
MOST SUSCEPTIBLE TO FLASH FLOODING AS WATER LEVELS ARE ALREADY
HIGH.
TEMPERATURES WILL QUICKLY FALL BEHIND THE LINE OF STORMS AND LOWS
WILL BE IN THE UPPER 60S TO LOWER 70S.
SUNDAY AND MONDAY...
THE UPPER LEVEL LOW SPLITS SUNDAY NIGHT AND THE FIRST TROUGH AXIS
MOVES THROUGH MONDAY NIGHT. AT THE SURFACE A SECOND COLD FRONT
MOVES THROUGH SUNDAY AND THEN STALLS OUT JUST SOUTH OF THE CWA
MONDAY MORNING. THE HIGHEST INSTABILITY VALUES WILL BE SOUTH OF I-80
SO ONLY HAVE A CHANCE OF STORMS SOUTH OF I-80. NOT EXPECTING MUCH IN
THE WAY OF PRECIP AT THIS TIME.
A BAND OF SHOWERS AND STORMS MAY FORM SUNDAY NIGHT FIRST ALONG THE
IL/WI STATE LINE AND THEN SPREAD SOUTH AS A VORTICITY STREAMER FROM
THE UPPER LEVEL LOW PUSHES SOUTH THROUGH THE REGION. THE SHOWERS
MAY PERSIST INTO LATE SUNDAY NIGHT AND BY THEN ONLY EXPECTING
SHOWERS. CONFIDENCE IS MEDIUM WITH THE STORMS DEVELOPING AND
COVERAGE.
YET ANOTHER COLD FRONT COMES THROUGH MONDAY AND HAVE A CHANCE OF
SHOWERS AND STORMS MONDAY AFTERNOON AND EVENING. THE BIGGER STORY
WILL BE THE COOL AIR THAT FOLLOWS THE COLD FRONT. HIGHS ON SUNDAY
WILL BE IN THE LOWER 80S WHILE MONDAY/S HIGHS WILL BE IN THE MID TO
UPPER 70S. MONDAY NIGHT LOOKS CRISP WITH LOWS IN THE LOWER 50S.
EXTENDED...TUESDAY THROUGH FRIDAY...
THE UPPER LEVEL TROUGH SLOWLY LIFTS NE THROUGH THURSDAY WHILE A
SURFACE HIGH BUILDS OVER THE REGION TUESDAY NIGHT. THE EXTENDED
LOOKS DRY WITH BELOW NORMAL TEMPERATURES.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* BREEZY SOUTHWEST WINDS GUSTING 20-25 KT THROUGH AFTERNOON.
* LOW CHANCE OF SHRA/TSRA LATE AFTERNOON INTO EARLY
EVENING...SHRA/TSRA EXPECTED SOME TIME AROUND MID EVENING. GUSTY
WINDS AND HEAVY RAINFALL POSSIBLE.
* MVFR CIGS EXPECTED TO SCATTER TO VFR MID AFTERNOON.
MDB
//DISCUSSION...UPDATED 18Z...
SOUTHWEST WINDS ARE STARTING TO INCREASE IN SPEED WITH GUSTS IN
THE 20-25 KT RANGE. CIGS ARE STARTING TO IMPROVE WITH MAINLY MVFR
IN PLACE. A LOOK OUT THE WINDOW AT THE OFFICE SHOWS STEADY
SCATTERING OF THE LOWEST CLOUDS WHICH SUPPORTS THE THINKING THAT
IMPROVEMENT TO VFR WILL OCCUR OVER THE NEXT FEW HOURS. FOCUS TURNS
TO TIMING OF SHRA/TSRA INTO THE EVENING. NOT MUCH IN THE WAY OF
FOCUS FOR DEVELOPMENT THROUGH MID AFTERNOON BUT FORCING WILL
INCREASE FAR NORTHWEST LATE THIS AFTERNOON. SOME SCATTERED
ACTIVITY IS POSSIBLE UP TOWARDS RFD BY THEN BUT THE FOCUS FOR THE
MOST WIDESPREAD DEVELOPMENT WILL BE ALONG A FRONTAL BOUNDARY FROM
SOUTHERN WISCONSIN WEST-SOUTHWEST INTO EASTERN IOWA. THIS ACTIVITY
WILL SAG SOUTHWARD THIS EVENING. TIMING IS STILL IN QUESTION SO
FURTHER ADJUSTMENTS MAY BE NEEDED BUT AT THIS POINT EARLY EVENING
IS FAVORED AT RFD WITH MID EVENING IN THE CHICAGO AREA AND
SLIGHTLY LATER AT GYY AS THINGS SAG SOUTHWARD. THE FRONT WILL BE
FAIRLY SLOW TO MOVE SO TRAINING OF STORMS ALONG THE FRONT IS
EXPECTED LEADING TO A FAIRLY LONG DURATION OF THUNDER. TORRENTIAL
RAINFALL MAY BRING VSBY DOWN BELOW 1SM BUT WILL HOLD OFF ON THIS
DETAIL IN THE TAF UNTIL IT BECOMES MORE CLEAR. WINDS MAY BE
ERRATIC OVERNIGHT BEHIND THE FRONT BUT TREND TO WEST THEN
NORTHWEST INTO SUNDAY MORNING. MVFR MAY LINGER BEHIND THE FRONT AS
WELL BUT VFR SHOULD BUILD IN.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE IN WINDS.
* HIGH CONFIDENCE THAT CHANCE FOR SHRA/TSRA IS LOW LATER THIS
AFTERNOON AND SHRA/TSRA IS LIKELY THIS EVENING. MEDIUM
CONFIDENCE IN TIMING THIS EVENING.
* MEDIUM-HIGH CONFIDENCE IN MVFR IMPROVING TO VFR THIS AFTERNOON.
LOW-MEDIUM CONFIDENCE IN TIMING.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY-MONDAY...LOW CHANCES OF TSRA.
TUESDAY...SLIGHT CHANCE OF SHRA.
WEDNESDAY-THURSDAY...VFR LIKELY.
KMD
&&
.MARINE...
244 AM CDT
STILL SEEING GUSTS TO NEAR 20 KT ON THE NORTHERN HALF OF THE
LAKE...BUT DO EXPECT THE PRESSURE GRADIENT TO RELAX TONIGHT INTO
SATURDAY AS HIGH PRESSURE ALONG THE ATLANTIC COAST CONTINUES EAST.
A TROUGH OF LOW PRESS SURE AND FRONTAL BOUNDARY WILL CROSS THE LAKE
ON SATURDAY NIGHT. CONFIDENCE IS LOWER WITH REGARDS TO OVERALL
WIND DIRECTION AND SPEEDS SATURDAY EVENING INTO SATURDAY NIGHT AS
PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED ALONG THIS
FRONTAL BOUNDARY. A SERIES OF WEAK LOW PRESSURE SYSTEMS AND
ASSOCIATED COLD FRONTS WILL THEN PASS THROUGH THE LAKE THROUGH
MONDAY WHILE HIGH PRESSURE BUILDS INTO THE NORTHERN CENTRAL
PLAINS. WINDS SHIFT TO WEST- NORTHWEST BEHIND THE STRONGER COLD
FRONTAL PUSH MONDAY NIGHT AND REACH 20 KT OR POSSIBLY HIGHER
TUESDAY.
KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS DES MOINES IA
330 PM CDT SAT JUL 12 2014
.SHORT TERM /TONIGHT/...
ISSUED AT 326 PM CDT SAT JUL 12 2014
MAIN CHALLENGE THIS PERIOD WILL BE EXTENT OF CONVECTION AND SEVERE
THREAT. MOST OF THE SYNOPTIC SCALE MODELS CONTINUE TO INDICATE
CONVERGENCE AND INSTABILITY SHOULD BE SUFFICIENT TO INITIATE
CONVECTION BETWEEN 3 TO 5 PM OVER CENTRAL IOWA BETWEEN US 20 AND US
30 THIS AFTERNOON...THEN SWINGING ACTIVITY OVER THE REMAINDER OF
THE AREA BETWEEN 5 PM AND 3 AM. SOME OF THE MESO MODELS AT ODDS
WITH MORE FOCUS ON BANDING SHOWERS/ISO THUNDER NORTH OF US 20 AND
SOME ADDITIONAL DEVELOPMENT OVER THE FAR SOUTH... ESPECIALLY
NEARER 06Z ALONG THE IA/MO BORDER WHEN LOW LEVEL JET INCREASES
ACROSS EXITING BOUNDARY. CURRENT MESO ANALYSIS SHOWS THE SOUTH
HALF NEARLY UNCAPPED WITH 3000 TO 3500 J/KG SBCAPE AND INCREASING
SFC CONVERGENCE ALONG BOUNDARY DRIFTING SOUTH AND CURRENTLY
LOCATED FROM EAST OF MASON CITY SOUTHWEST TO ABOUT OMAHA. H700
TEMPS SUGGEST WEAK CAP OF 10C AT THAT LEVEL FOR NOW...BUT EXPECT
THAT TO WEAKEN YET BY LATE AFTERNOON. EFFECTIVE BULK SHEAR
SUFFICIENT FOR SUPERCELL DEVELOPMENT. SOUNDINGS ACROSS THE SOUTH
SHOW SOME DRYING AROUND H700 SO EXPECT THAT WIND WILL REMAIN THE
GREATER THREAT THIS AFTERNOON/EVENING ALONG WITH AN ISOLATED
TORNADO. 0-3KM CAPE ALREADY NEAR 125 J/KG WITH LCL HTS NEAR 1000
TO 1250 M OVER THE SOUTH AS WELL. WITH WARM CLOUD DEPTHS
APPROACHING 15 KFT AND PRECIPITABLE WATER QUITE HIGH AT 2 TO 2.25
INCHES AVAILABLE THROUGH THE EVENING SOUTH HALF THERE WILL BE A
POTENTIAL FOR A QUICK RAINFALL TOTAL OF +2 INCHES WITH ANY OF THE
STRONGER STORMS. ALONG WITH THAT...A POTENTIAL FOR LOCALIZED WATER
ISSUES AND POSSIBLE FLASH FLOODING REMAINS. CONFIDENCE ON
WIDESPREAD HEAVY RAINFALL COVERAGE REMAINS TOO LOW FOR A FLASH
FLOOD WATCH. WITH RATHER WEAK CONVERGENCE AND THUNDERSTORM
DEVELOPMENT CONDITIONAL ON CAP BREAKING...WILL KEEP THUNDER
CHANCES AT SLIGHT/CHANCE CATEGORY THROUGH MID AFTERNOON SOUTH AND
THEN INCREASE POP THROUGH 23-03Z TIME FRAME. ACROSS THE NORTH
ACTIVITY SHOULD BE NEARING AN END AROUND 00Z-02Z. LOOKING AT ALL
THE DATA...FEEL THE HRRR AND HOP WRF MAY BE TOO PESSIMISTIC WITH
LACK OF THUNDER DEVELOPMENT ACROSS THE WARM SECTOR. LATEST 4 KM
WRF SHOWS INCREASING COVERAGE FROM US 20 SOUTH THIS
AFTERNOON...MATCHING UP BETTER WITH THE SYNOPTIC SCALE SOLUTIONS.
LOWS TONIGHT WILL DROP TO NEAR 60 NORTH AND IN THE UPPER 60S SOUTH
AS COOLER AIR FILTERS INTO THE REGION BY SUNDAY MORNING.
.LONG TERM /SUNDAY THROUGH SATURDAY/...
ISSUED AT 326 PM CDT SAT JUL 12 2014
MAIN CONCERN REMAINS FOCUSED ON UNSEASONABLY COLD TEMPERATURES TO
FILTER INTO THE STATE MONDAY THROUGH WEDNESDAY...AND THEN MILD
AND DRY CONDITIONS THROUGH THE END OF THE WORK WEEK.
SUNDAY INTO MONDAY...SECONDARY TROUGH/COLD FRONT LOOKS TO PUSH
ACROSS THE STATE ON SUNDAY AND MAY BRING A FEW LIGHT SHOWERS AND
AN ISOLATED THUNDERSTORMS IN THE AFTERNOON WITH SOME MARGINAL
INSTABILITY RECOVERING FROM CONVECTION TONIGHT. SURFACE DEWPOINTS
LOOK TO BE ABOUT 10 DEGREES LESS THAN TODAY BUT ENOUGH MOISTURE
AVAILABLE COMBINED WITH WEAK FORCING WITH BOUNDARY MOVING
THROUGH...SO KEPT SLIGHT POPS GOING IN THE AFTERNOON SUNDAY.
ANOTHER STRONGER COLD FRONT TO BRING THE WELL ANTICIPATED
UNSEASONABLY COOL TEMPERATURES WILL PUSH THROUGH THE STATE DURING
THE DAY MONDAY. GOOD MIXING BEHIND THE FRONT BY THE AFTERNOON AND
TWEAKED UP WINDS SLIGHTLY. LOW CONFIDENCE WITH MENTION THE NON-
DIURNAL TEMP TREND ON MONDAY WITH THE CAA AS SUN ANGLE STILL HIGH
ENOUGH TO WARM TEMPS UP IN THE AFTERNOON.
TUESDAY THROUGH SATURDAY...VERY COLD AIRMASS FOR THIS TIME OF YEAR
TO FILTER INTO THE STATE AS 850MB TEMPS DROP TO +5C TO +6C BY EARLY
TUESDAY MORNING. KEPT MENTION OF NEAR RECORD LOWS FOR TUESDAY
MORNING AS SURFACE RIDGE LOOKS TO BE CENTERED OVER EASTERN IOWA INTO
THE WESTERN GREAT LAKES BY 12Z TUESDAY AND EXPECTING DECENT
RADIATIONAL COOLING TO DEVELOP. SURFACE DEWPOINTS DROP TO AROUND 50F
BY TUESDAY MORNING AND WITH THE RADIATION COOLING EVENT...COULD SEE
SOME SHALLOW FOG DEVELOP IF WINDS DROP OFF ENTIRELY. SOMETHING TO
CONSIDER WITH NEXT FORECAST PACKAGE.
COOL AIRMASS REMAINS IN PLACE THROUGH MUCH OF THE WORK WEEK BEFORE
IT BEGINS MODERATE BACK TO NORMAL TEMPERATURES BY FRIDAY INTO
SATURDAY OF NEXT WEEK. NO SIGNIFICANT SYSTEM TO BRING PRECIPITATION
TO CENTRAL IOWA FROM MID TO LATE WEEK NEXT WEEK.
&&
.AVIATION...12/18Z
ISSUED AT 105 PM CDT SAT JUL 12 2014
FRONTAL BOUNDARY DRIFTING SOUTH THIS AFTERNOON AND EVENING. SHRA
CONTINUE ALONG THE BOUNDARY OVER NORTHERN IOWA WITH GENERALLY
UNSTABLE CONDITIONS DEVELOPING ACROSS THE SOUTH. EXPECTING LINE
OF SHOWERS TO BECOME MORE CONVECTIVE THIS AFTERNOON WITH POTENTIAL
FOR BRIEF PERIOD OF HEAVIER RAINFALL AND MVFR VSBY. TIMING FOR
NORTHERN AREAS BETWEEN 19 AND 00Z...FROM US 20 SOUTH TO HIGHWAY
30...22Z THROUGH 03Z AND SOUTH OF HIGHWAY 30 FROM 23Z THROUGH 06Z.
BEST CHANCES FOR SVR CONVECTION WILL BE FOR KDSM AND KOTM AS MAX
INSTABILITY EXPECTED THERE FROM 21Z THROUGH 03Z. SVR THREAT MOST
LIKELY WIND GUSTS ABOVE 45 TO 50 KTS. HAVE NOT ADDED TO TAFS AT
THIS TIME...DUE TO TIMING/UNCERTAINTY CONSIDERATIONS...BUT WILL
MONITOR/ADD AS NEEDED WHEN TRENDS BECOME MORE EVIDENT. AFT 06Z
MOST AREA WILL BE VFR WITH LIGHT NW WINDS BECOMING 10-15KTS AFT
15Z SUNDAY... ESPECIALLY NORTH HALF. /REV
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...REV
LONG TERM...PODRAZIK
AVIATION...REV
AREA FORECAST DISCUSSION
NWS TOPEKA KS
340 PM CDT Sat Jul 12 2014
.SHORT TERM...(This Evening through Sunday)
Issued at 336 PM CDT SAT JUL 12 2014
19Z water vapor imagery shows a broad mid level ridge centered over
northern OK/southern KS while a deep closed low spun over Manitoba
and was beginning to move south. One trough axis appears to have
rotated through NEB with a second shortwave trough digging southeast
through ND. At the surface a cold front stretched from northwest KS
into central IA, and has been slowly moving southeast this afternoon.
For tonight and Sunday, the models continue to show the cold front
moving through the forecast area late tonight. This seems to make
since with the initial mid level trough rotating through IA tonight
and the ridge overhead breaking down. Most of the model guidance
shows a well defined band of frontogenesis within the mid levels of
the atmosphere along with a narrow axis of moisture. This appears to
be the main driver of precip tonight and Sunday as forecast
soundings continue to show limited moisture in the lower atmosphere.
So think there is a good chance for elevated showers and storms to
develop this evening and overnight rather than deep moist convection
from surface parcels. Not sure if the HRRR is handling the
frontogenesis as well as it depicts convection and is the reason it
has been one of the drier solutions. Would not be surprised to see
precip lingering through the morning much like it has over
northeastern NEB and northern IA today. Since I`m expecting precip
to be elevated, chances for severe weather appear to be very limited
due to modest elevated instability from 700-500MB lapse rates only
around 6 C/km.
There does not appear to be a big surge in cold dry air behind the
front tonight. Obs upstream show decent moisture pooling behind the
boundary. With mostly cloudy skies anticipated behind the front and
dewpoints remaining in the mid and upper 60s behind the front, think
lows will once again be mild. Areas along the NEB state line should
see lows in the upper 60s while elsewhere is expected to remain in
the lower 70s. Think highs Sunday will depend on how much insolation
reaches the ground. With skies likely to remain partly to mostly
cloudy across east central KS from the elevated showers, have highs
in the mid 80s across Anderson and Coffey counties. Elsewhere think there
could be enough sunshine for highs to reach the upper 80s to around
90. Considered maybe bumping highs up a degree or two from what I
have now since there isn`t a lot of cold air advection behind the
front, but held off since models show some cooling at 850 and the
thermal ridge setting up further south.
.LONG TERM...(Sunday Night through Saturday)
Issued at 336 PM CDT SAT JUL 12 2014
Will linger a low pop across the far southeast counties of the cwa for
Sunday evening...otherwise will leave the remainder of the forecast dry
overnight except for the far northwest corner with the approach of the
next shortwave trough. As this wave and stronger cold front moves
through...mid level frontogenesis will increase from north to south
through midday with decreasing lift in the mid to late afternoon
across the southern cwa. Will therefore go dry all areas of the
county warning area. Rainfall amounts will generally average a tenth
to a third of an inch during the day.
Much cooler and drier air works southward across the cwa through the
night with 850 temps by sunrise Tuesday falling into the 7 to 10 deg
C range with diminishing winds and mostly clear skies. This will
probably be the coolest morning of the week with lows in the low to
middle 50s all areas which will be near or just above record lows
for July 15th.
By late Tuesday night models try to bring the remnants of an MCS
east and southeast across central Ks which may clip the far
southwest corner of the cwa by sunrise...then the southern half of
the cwa during the day. Have inserted low pops across this
area...and inched low temps up due to more cloudcover...but still
unseasonably cool in the middle to upper 50s and highs in the 70s.
As another northwest flow shortwave moves from the central high
plains into the southern plains...most of the precip through the end
of the week should remain south of the cwa with weak upper ridging
building back into the area by the weekend. Will keep the remainder
of the fcst beyond Wednesday dry with a gradual warming trend. Highs
will warm through the 80s as low temps moderate through the 60s to
around 70 by Saturday night.
&&
.AVIATION...(For the 18Z TAFs through 18Z Sunday Afternoon)
Issued at 1230 PM CDT SAT JUL 12 2014
VFR conditions should prevail through this evening due to the
surface front remaining north of the terminals while mid level
ridging sits overhead. The NAM and GFS show a decent band of mid
level frontogenesis collocated with some saturation directly behind
the surface front. Because of this think high based SCT SH and
embedded TS are possible on the north side of the boundary as it
moves south late tonight. Therefore have maintained a VCTS for the
early morning hours. Elevated instability appears to be limited so
precip looks to be light and there may not even be a VSBY
restriction with the precip. Will have to reevaluate this as the
front gets closer.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Wolters
LONG TERM...63
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS JACKSON KY
614 PM EDT SAT JUL 12 2014
.UPDATE...
ISSUED AT 614 PM EDT SAT JUL 12 2014
A SIGNIFICANT AMOUNT OF CIRRUS HAS MOVED INTO THE REGION...BUT IT
WAS GRADUALLY DISSIPATING. INCREASED SKY COVER FOR EARLY THIS
EVENING...BUT STAYED WITH A TREND TOWARD THE LOWER VALUES OF THE
PREVIOUS FORECAST FOR LATE TONIGHT. DRY SURFACE AIR AND WARM AIR
ADVECTION TONIGHT WOULD FAVOR SOME RIDGE/VALLEY TEMPERATURE
DIFFERENCES...AND HAVE LOWERED VALLEY MINS JUST A BIT FOR TONIGHT.
WITHOUT OVERCAST SKIES OR SIGNIFICANT WIND...CLIMATOLOGY STRONGLY
FAVORS AT LEAST SOME FOG IN THE DEEPER VALLEYS AT THIS TIME OF YEAR.
SO...DESPITE THE DRY AIR...HAVE ADDED SOME PATCHY FOG IN VALLEYS FOR
LATE TONIGHT...BUT PREVIOUS THINKING OF LESS SUBSTANTIAL FOG THAN IN
RECENT NIGHTS SHOULD STILL PLAY OUT.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 315 PM EDT SAT JUL 12 2014
ISOLATED CONVECTION MAINLY TIED TO TERRAIN IS EXPECTED TO REMAIN TO
OUR SOUTH AND SOUTHEAST OVER SW VA AND THE HIGHER TERRAIN OF TN AND
NC FOR THE REMAINDER OF THIS AFTERNOON. THE AREA OF SHOWERS AND
THUNDERSTORMS OVER WESTERN INDIANA AND WESTERN KY IS AHEAD OF A NEARLY
STATIONARY WARM FRONTAL BOUNDARY THAT REPRESENTS THE LEADING EDGE OF
70 PLUS DEW POINT TEMPERATURES OVER IL AND MO. SATELLITE...RADAR AND
LIGHTNING TRENDS ALL SHOW CONTINUING WEAKENING OF CONVECTION OVER
INDIANA...BUT THERE HAS BEEN SOME DEVELOPMENT INTO WESTERN KY. THE
SHORT RANGE RAP AND HRRR CONTINUE TO SHOW OVERALL DECAY OF CONVECTION
TO OUR WEST...AND ONLY IMPACT IN OUR AREA WILL BE SOME INCREASE IN
HIGH LEVEL CLOUDS.
WITH VERY DRY LOW LEVEL AIR IN PLACE IN EASTERN KY THIS
AFTERNOON...NOTE DEW POINT AS LOW AS 48 AT QUICKSAND MESONET...THERE
WILL BE EVEN LESS FOG TONIGHT AS THERE WAS LAST NIGHT. GUIDANCE NOT
HANDLING THE DRY AIR VERY WELL...AND EXPECT THERE TO BE ABOUT A 5
DEGREE RIDGE VALLEY TEMPERATURE SPLIT FOR TONIGHT.
ON SUNDAY INSTABILITY WILL INCREASE AHEAD OF AN APPROACHING COLD
FRONT WITH MUCAPE IN EXCESS OF 4000 J/KG DEVELOPING IN A CORRIDOR
NORTH OF THE OH RIVER ACROSS SOUTHERN IN AND OH. BEST SHEAR WILL ALSO
BE NORTH OF THE OH RIVER SUNDAY AFTERNOON AND CURRENT THINKING IS
THAT THUNDERSTORMS WILL DEVELOP ACROSS OH AND INDIANA AND THEN
PROGRESS INTO NORTHERN PARTS OF THE FORECAST AREA LATE SUNDAY
AFTERNOON OR SUNDAY NIGHT. AT THE SAME TIME SOME ISOLATED TO
SCATTERED CONVECTION MAY DEVELOP OVER THE SOUTHEAST MOUNTAINS SUNDAY
AFTERNOON. THIS WOULD ALSO BE IN A CORRIDOR OF SLIGHTLY GREATER
INSTABILITY AND ALSO PARTIALLY TIED TO THE HIGHER TERRAIN. THE MODELS
HAVE BEEN CONSISTENT AT HINTING AT THIS POSSIBILITY IN THE SE
FORECAST AREA. CONSIDERING ALL THIS WILL BRING CHANCE PROBABILITY OF
SHOWERS AND THUNDERSTORMS TO THE SOUTHEAST AND NORTHERN PARTS OF THE
FORECAST AREA FIRST ON SUNDAY...WITH THE CENTRAL AND SOUTHWEST PARTS
OF THE FORECAST AREA THE LAST TO SEE THE RAIN CHANCES.
THE CONVECTION THAT DEVELOPS TO OUR NORTH ON SUNDAY HAS SEVERE
POTENTIAL...BUT AS IT MOVES INTO OUR AREA SUNDAY NIGHT AWAY FROM
BEST SUPPORT...THE SEVERE THREAT WILL DECREASE. THE DAY 2 SEVERE
WEATHER OUTLOOK WITH ONLY OUR FAR NW COUNTIES HAVING A SLIGHT RISK OF
SEVERE WEATHER THROUGH 12Z MONDAY CONTINUES TO LOOK GOOD. WITH PW
INCREASING THROUGH SUNDAY NIGHT TO 1.7 TO POSSIBLY GREATER THAN 2
INCHES SOME HEAVY RAINERS ARE DEFINITELY A POSSIBILITY SUNDAY NIGHT. MUCH
OF THE AREA HAS BEEN PLACED IN THE DAY 2 EXCESSIVE RAINFALL OUTLOOK
VALID 00Z MONDAY TO 00Z TUESDAY. FLASH FLOOD GUIDANCE IS FAIRLY HIGH
HOWEVER...AND PART OF THE AREA IS CURRENTLY IN D1 DROUGHT. INITIALLY...
AT LEAST FOR SUNDAY NIGHT...WHICH IS THE FIRST HALF OF THIS OUTLOOK
PERIOD THE FLASH FLOOD THREAT LOOKS BE ISOLATED AT WORST.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 315 PM EDT SAT JUL 12 2014
THE GFS IS SHOWING SOME DECENT CONTINUITY THROUGH THE LAST FEW
CYCLES BUT STILL APPEARS OUTSIDE THE RANGE OF OTHER SOLUTIONS AND
TOO PROGRESSIVE...ESPECIALLY CONSIDERING THE EXPECTED AMPLITUDE OF
THE MID AND UPPER LEVEL PATTERNS. THE ECMWF...WHICH HAS BEEN MORE
CONSISTENT IS ADVERTISING A SLOWER SYSTEM THAT PUNCHES FURTHER SOUTH
THAN OTHER MODELS AND IS ON THE SLOWER SIDE OF THE ENVELOPE OF
SOLUTIONS THROUGH THE MID TERM. JUST THE SAME MODELS ROUGHLY AGREE
ON THE OVERALL SCENARIO OF THE LARGE SCALE PATTERN. THE MAIN...AND
MOST SIGNIFICANT DIFFERENCES CROP UP RESOLVING SURFACE FEATURES AND
THE TIMING OF SFC SYSTEMS THROUGH OUR AREA. ATTM TENDENCY IS TO LEAN
TOWARDS THE ECMWF SOLUTION THROUGH THE MID RANGE AFTER USING A
CONSENSUS SOLUTION TO INITIALIZE THE EXTENDED PORTION OF THE
FORECAST PACKAGE. WILL STICK TO A BLENDED APPROACH FOR THE END OF
THE FORECAST WINDOW AS ADDITIONAL ENERGY EMERGES FROM THE PACIFIC
NW/CANADA CAUSING THE PATTERN TO BECOME LESS AMPLIFIED...BUT ALSO
ALLOWING FOR THE MEAN STORM TRACK TO RETURN NORTHWARD CLOSER TO OUR
NECK OF THE WOODS.
HEIGHTS FALL DROP STEADILY THROUGH THE FIRST HALF OF THE PERIOD AS A
SPLITTING UPPER LEVEL LOW DROPS A SIGNIFICANT PORTION OF ITS ENERGY
INTO THE THE UPPER MIDWEST AND GREAT LAKES...RESULTING IN A LARGE
DEEP TROUGH ACROSS THE ENTIRE EASTERN CONUS BY MID WEEK. SURFACE
FRONTAL ZONE WILL DROP SOUTHWARD ALONG THE OHIO RIVER BY LATE SUNDAY
OR SUNDAY NIGHT. A SECOND STRONGER...FASTER FRONTAL BOUNDARY WILL
FOLLOW QUICKLY BEHIND THE FIRST SLIDING THROUGH OUR AREA AS SOON AS
MONDAY NIGHT...OR AS LATE AS TUESDAY AFTERNOON DEPENDING ON WHICH
MODEL YOU LOOK AT. IT STILL SEEMS LIKE THE GFS IS HAVING TROUBLE
RESOLVING THE TIMING OR PASSAGE OF THESE TWO FRONTAL BOUNDARIES...
WITH A TENDENCY TO MERGE EACH DISTINCT BOUNDARY INTO A SINGLE FINAL
SYSTEM THAT MOVES THROUGH EASTERN KENTUCKY TOO QUICKLY.
WE ARE STILL LOOKING AT THE POTENTIAL FOR SOME SEVERE WEATHER THOUGH
THE TIME OF DAY AND EXACT AMOUNT OF SUNLIGHT WILL BE SOMETHING THAT
WILL NEED TO BE FACTORED IN. AS IS TYPICAL...THE NAM IS CONSIDERABLY
MORE UNSTABLE IN THE BOUNDARY LAYER BECAUSE OF ITS WET BIAS. THE NAM
IS ALSO SHOWING HIGHER BULK SHEAR VALUES THROUGH THE EARLY MONDAY
MORNING TO MONDAY AFTERNOON TIME FRAME. PWATS AND LIFT THROUGH THE
COLUMN ARE MUCH MORE IMPRESSIVE AS WELL WHEN COMPARED TO THE GFS.
EXPECT THE TRUTH WILL LIE SOMEWHERE IN THE MIDDLE THOUGH THAT MAY BE
A BAD ASSUMPTION GIVEN THE GFS MIGHT BE HAVING TROUBLE
DISTINGUISHING SURFACE AND BOUNDARY LAYER DETAILS. FREEZING LEVELS
REMAIN HIGH. SO WHILE SOME HEAVY RAIN CAN NOT BE RULED OUT...STORM
MOTION IS HIGH ENOUGH THAT HYDRO PROBLEMS SHOULD NOT BECOME TOO MUCH
OF A PROBLEM...AT LEAST BASED ON CURRENT GUIDANCE. BIGGEST THREAT
FOR SEVERE WEATHER WILL GENERALLY LIE ACROSS OUR BLUE GRASS COUNTIES
SUNDAY...BUT THEN EXPAND SOUTHEASTWARD TO ENCOMPASS OUR ENTIRE
FORECAST AREA BY MONDAY.
WE ARE STILL LOOKING AT UNSEASONABLE COLD WEATHER FOR THE PEAK OF
SUMMER HEATING THROUGH THE MIDDLE OF UPCOMING WEEK. ECMWF H850 TEMPS
DROP TO AROUND 8C AND THE GFS HAS TRENDED TOWARDS THE ECMWF. ECMWF
MOS GUIDANCE IS QUITE COOL WITH AFTERNOON HIGHS IN THE LOWER TO MID
70S AND LOWS SOLIDLY IN THE 50S FROM TUESDAY THROUGH FRIDAY. WHILE
THERE IS SOME MODERATION TOWARDS THE END OF THE WEEK...THERE IS A
GOOD POTENTIAL FOR SOME RECORD COLD MORNING LOWS AND EVEN A FEW
RECORD LOW MAXES. GFS MOS IS CONSIDERABLY WARMER BUT HAS SHOWN SIGNS
OF COOLING. PAST EXPERIENCE HAS TAUGHT THAT A BLEND OF GUIDANCE
MAKES A BEST FIRST GUESS...AFTER A TWEAK TOWARDS THE TYPICALLY MORE
ACCURATE ECMWF MOS.
ADDITIONAL ENERGY MOVING OUT OF THE NORTHWEST AND INTO THE BASE OF
THE BY THEN LIFTING EASTERN CONUS TROUGH WILL BRING A THREAT OF RAIN
BACK INTO THE FORECAST AREA AT THE END OF THE WEEK AND INTO THE
WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 116 PM EDT SAT JUL 12 2014
SCATTERED CUMULUS AROUND 5K TO 6K FEET WITH LIGHT WINDS CAN BE
EXPECTED THIS AFTERNOON AS HIGH PRESSURE CONTINUES TO CONTROL THE
LOCAL WEATHER. ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
REMAIN JUST OUTSIDE OF THE FORECAST AREA THIS AFTERNOON IN THE HIGHER
TERRAIN OF SW VA...TN AND NC. THERE WAS LESS FOG THIS MORNING THAN
YESTERDAY MORNING AND EXPECT THAT TREND TO CONTINUE. AS SUCH WILL
LEAVE FOG OUT OF TAFS FOR THIS FORECAST. VFR CONDITIONS WILL PREVAIL
AGAIN ON SUNDAY...BUT SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE BY
SUNDAY NIGHT AHEAD OF A COLD FRONT DROPPING SOUTH ACROSS OH AND
INDIANA.
.JKL WATCHES/WARNINGS/ADVISORIES...
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...SBH
LONG TERM...RAY
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS JACKSON KY
316 PM EDT SAT JUL 12 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 315 PM EDT SAT JUL 12 2014
ISOLATED CONVECTION MAINLY TIED TO TERRAIN IS EXPECTED TO REMAIN TO
OUR SOUTH AND SOUTHEAST OVER SW VA AND THE HIGHER TERRAIN OF TN AND
NC FOR THE REMAINDER OF THIS AFTERNOON. THE AREA OF SHOWERS AND
THUNDERSTORMS OVER WESTERN INDIANA AND WESTERN KY IS AHEAD OF A NEARLY
STATIONARY WARM FRONTAL BOUNDARY THAT REPRESENTS THE LEADING EDGE OF
70 PLUS DEWPOINT TEMPERATURES OVER IL AND MO. SATELLITE...RADAR AND
LIGHTNING TRENDS ALL SHOW CONTINUING WEAKENING OF CONVECTION OVER
INDIANA...BUT THERE HAS BEEN SOME DEVELOPMENT INTO WESTERN KY. THE
SHORT RANGE RAP AND HRRR CONTINUE TO SHOW OVERALL DECAY OF CONVECTION
TO OUR WEST...AND ONLY IMPACT IN OUR AREA WILL BE SOME INCREASE IN
HIGH LEVEL CLOUDS.
WITH VERY DRY LOW LEVEL AIR IN PLACE IN EASTERN KY THIS
AFTERNOON...NOTE DEWPOINT AS LOW AS 48 AT QUICKSAND MESONET...THERE
WILL BE EVEN LESS FOG TONIGHT AS THERE WAS LAST NIGHT. GUIDANCE NOT
HANDLING THE DRY AIR VERY WELL...AND EXPECT THERE TO BE ABOUT A 5
DEGREE RIDGE VALLEY TEMPERATURE SPLIT FOR TONIGHT.
ON SUNDAY INSTABILITY WILL INCREASE AHEAD OF AN APPROACHING COLD
FRONT WITH MUCAPE IN EXCESS OF 4000 J/KG DEVELOPING IN A CORRIDOR
NORTH OF THE OH RIVER ACROSS SOUTHERN IN AND OH. BEST SHEAR WILL ALSO
BE NORTH OF THE OH RIVER SUNDAY AFTERNOON AND CURRENT THINKING IS
THAT THUNDERSTORMS WILL DEVELOP ACROSS OH AND INDIANA AND THEN
PROGRESS INTO NORTHERN PARTS OF THE FORECAST AREA LATE SUNDAY
AFTERNOON OR SUNDAY NIGHT. AT THE SAME TIME SOME ISOLATED TO
SCATTERED CONVECTION MAY DEVELOP OVER THE SOUTHEAST MOUNTAINS SUNDAY
AFTERNOON. THIS WOULD ALSO BE IN A CORRIDOR OF SLIGHTLY GREATER
INSTABILITY AND ALSO PARTIALLY TIED TO THE HIGHER TERRAIN. THE MODELS
HAVE BEEN CONSISTENT AT HINTING AT THIS POSSIBILITY IN THE SE
FORECAST AREA. CONSIDERING ALL THIS WILL BRING CHANCE PROBABILITY OF
SHOWERS AND THUNDERSTORMS TO THE SOUTHEAST AND NORTHERN PARTS OF THE
FORECAST AREA FIRST ON SUNDAY...WITH THE CENTRAL AND SOUTHWEST PARTS
OF THE FORECAST AREA THE LAST TO SEE THE RAIN CHANCES.
THE CONVECTION THAT DEVELOPS TO OUR NORTH ON SUNDAY HAS SEVERE
POTENTIAL...BUT AS IT MOVES INTO OUR AREA SUNDAY NIGHT AWAY FROM
BEST SUPPORT...THE SEVERE THREAT WILL DECREASE. THE DAY 2 SEVERE
WEATHER OUTLOOK WITH ONLY OUR FAR NW COUNTIES HAVING A SLIGHT RISK OF
SEVERE WEATHER THROUGH 12Z MONDAY CONTINUES TO LOOK GOOD. WITH PW
INCREASING THROUGH SUNDAY NIGHT TO 1.7 TO POSSIBLY GREATER THAN 2
INCHES SOME HEAVY RAINERS ARE DEFINITELY A POSSIBILITY SUNDAY NIGHT. MUCH
OF THE AREA HAS BEEN PLACED IN THE DAY 2 EXCESSIVE RAINFALL OUTLOOK
VALID 00Z MONDAY TO 00Z TUESDAY. FLASH FLOOD GUIDANCE IS FAIRLY HIGH
HOWEVER...AND PART OF THE AREA IS CURRENTLY IN D1 DROUGHT. INITIALLY...
AT LEAST FOR SUNDAY NIGHT...WHICH IS THE FIRST HALF OF THIS OUTLOOK
PERIOD THE FLASH FLOOD THREAT LOOKS BE ISOLATED AT WORST.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 315 PM EDT SAT JUL 12 2014
THE GFS IS SHOWING SOME DECENT CONTINUITY THROUGH THE LAST FEW
CYCLES BUT STILL APPEARS OUTSIDE THE RANGE OF OTHER SOLUTIONS AND
TOO PROGRESSIVE...ESPECIALLY CONSIDERING THE EXPECTED AMPLITUDE OF
THE MID AND UPPER LEVEL PATTERNS. THE ECMWF...WHICH HAS BEEN MORE
CONSISTENT IS ADVERTISING A SLOWER SYSTEM THAT PUNCHES FURTHER SOUTH
THAN OTHER MODELS AND IS ON THE SLOWER SIDE OF THE ENVELOPE OF
SOLUTIONS THROUGH THE MID TERM. JUST THE SAME MODELS ROUGHLY AGREE
ON THE OVERALL SCENARIO OF THE LARGE SCALE PATTERN. THE MAIN...AND
MOST SIGNIFICANT DIFFERENCES CROP UP RESOLVING SURFACE FEATURES AND
THE TIMING OF SFC SYSTEMS THROUGH OUR AREA. ATTM TENDENCY IS TO LEAN
TOWARDS THE ECMWF SOLUTION THROUGH THE MID RANGE AFTER USING A
CONSENSUS SOLUTION TO INITIALIZE THE EXTENDED PORTION OF THE
FORECAST PACKAGE. WILL STICK TO A BLENDED APPROACH FOR THE END OF
THE FORECAST WINDOW AS ADDITIONAL ENERGY EMERGES FROM THE PACIFIC
NW/CANADA CAUSING THE PATTERN TO BECOME LESS AMPLIFIED...BUT ALSO
ALLOWING FOR THE MEAN STORM TRACK TO RETURN NORTHWARD CLOSER TO OUR
NECK OF THE WOODS.
HEIGHTS FALL DROP STEADILY THROUGH THE FIRST HALF OF THE PERIOD AS A
SPLITTING UPPER LEVEL LOW DROPS A SIGNIFICANT PORTION OF ITS ENERGY
INTO THE THE UPPER MIDWEST AND GREAT LAKES...RESULTING IN A LARGE
DEEP TROUGH ACROSS THE ENTIRE EASTERN CONUS BY MID WEEK. SURFACE
FRONTAL ZONE WILL DROP SOUTHWARD ALONG THE OHIO RIVER BY LATE SUNDAY
OR SUNDAY NIGHT. A SECOND STRONGER...FASTER FRONTAL BOUNDARY WILL
FOLLOW QUICKLY BEHIND THE FIRST SLIDING THROUGH OUR AREA AS SOON AS
MONDAY NIGHT...OR AS LATE AS TUESDAY AFTERNOON DEPENDING ON WHICH
MODEL YOU LOOK AT. IT STILL SEEMS LIKE THE GFS IS HAVING TROUBLE
RESOLVING THE TIMING OR PASSAGE OF THESE TWO FRONTAL BOUNDARIES...
WITH A TENDENCY TO MERGE EACH DISTINCT BOUNDARY INTO A SINGLE FINAL
SYSTEM THAT MOVES THROUGH EASTERN KENTUCKY TOO QUICKLY.
WE ARE STILL LOOKING AT THE POTENTIAL FOR SOME SEVERE WEATHER THOUGH
THE TIME OF DAY AND EXACT AMOUNT OF SUNLIGHT WILL BE SOMETHING THAT
WILL NEED TO BE FACTORED IN. AS IS TYPICAL...THE NAM IS CONSIDERABLY
MORE UNSTABLE IN THE BOUNDARY LAYER BECAUSE OF ITS WET BIAS. THE NAM
IS ALSO SHOWING HIGHER BULK SHEAR VALUES THROUGH THE EARLY MONDAY
MORNING TO MONDAY AFTERNOON TIME FRAME. PWATS AND LIFT THROUGH THE
COLUMN ARE MUCH MORE IMPRESSIVE AS WELL WHEN COMPARED TO THE GFS.
EXPECT THE TRUTH WILL LIE SOMEWHERE IN THE MIDDLE THOUGH THAT MAY BE
A BAD ASSUMPTION GIVEN THE GFS MIGHT BE HAVING TROUBLE
DISTINGUISHING SURFACE AND BOUNDARY LAYER DETAILS. FREEZING LEVELS
REMAIN HIGH. SO WHILE SOME HEAVY RAIN CAN NOT BE RULED OUT...STORM
MOTION IS HIGH ENOUGH THAT HYDRO PROBLEMS SHOULD NOT BECOME TOO MUCH
OF A PROBLEM...AT LEAST BASED ON CURRENT GUIDANCE. BIGGEST THREAT
FOR SEVERE WEATHER WILL GENERALLY LIE ACROSS OUR BLUE GRASS COUNTIES
SUNDAY...BUT THEN EXPAND SOUTHEASTWARD TO ENCOMPASS OUR ENTIRE
FORECAST AREA BY MONDAY.
WE ARE STILL LOOKING AT UNSEASONABLE COLD WEATHER FOR THE PEAK OF
SUMMER HEATING THROUGH THE MIDDLE OF UPCOMING WEEK. ECMWF H850 TEMPS
DROP TO AROUND 8C AND THE GFS HAS TRENDED TOWARDS THE ECMWF. ECMWF
MOS GUIDANCE IS QUITE COOL WITH AFTERNOON HIGHS IN THE LOWER TO MID
70S AND LOWS SOLIDLY IN THE 50S FROM TUESDAY THROUGH FRIDAY. WHILE
THERE IS SOME MODERATION TOWARDS THE END OF THE WEEK...THERE IS A
GOOD POTENTIAL FOR SOME RECORD COLD MORNING LOWS AND EVEN A FEW
RECORD LOW MAXES. GFS MOS IS CONSIDERABLY WARMER BUT HAS SHOWN SIGNS
OF COOLING. PAST EXPERIENCE HAS TAUGHT THAT A BLEND OF GUIDANCE
MAKES A BEST FIRST GUESS...AFTER A TWEAK TOWARDS THE TYPICALLY MORE
ACCURATE ECMWF MOS.
ADDITIONAL ENERGY MOVING OUT OF THE NORTHWEST AND INTO THE BASE OF
THE BY THEN LIFTING EASTERN CONUS TROUGH WILL BRING A THREAT OF RAIN
BACK INTO THE FORECAST AREA AT THE END OF THE WEEK AND INTO THE
WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 116 PM EDT SAT JUL 12 2014
SCATTERED CUMULUS AROUND 5K TO 6K FEET WITH LIGHT WINDS CAN BE
EXPECTED THIS AFTERNOON AS HIGH PRESSURE CONTINUES TO CONTROL THE
LOCAL WEATHER. ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
REMAIN JUST OUTSIDE OF THE FORECAST AREA THIS AFTERNOON IN THE HIGHER
TERRAIN OF SW VA...TN AND NC. THERE WAS LESS FOG THIS MORNING THAN
YESTERDAY MORNING AND EXPECT THAT TREND TO CONTINUE. AS SUCH WILL
LEAVE FOG OUT OF TAFS FOR THIS FORECAST. VFR CONDITIONS WILL PREVAIL
AGAIN ON SUNDAY...BUT SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE BY
SUNDAY NIGHT AHEAD OF A COLD FRONT DROPPING SOUTH ACROSS OH AND
INDIANA.
.JKL WATCHES/WARNINGS/ADVISORIES...
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...SBH
LONG TERM...RAY
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS JACKSON KY
116 PM EDT SAT JUL 12 2014
.UPDATE...
ISSUED AT 116 PM EDT SAT JUL 12 2014
ISOLATED CONVECTION MAINLY TIED TO TERRAIN IS EXPECTED TO REMAIN TO
OUR SOUTHEAST THIS AFTERNOON AND WILL NOT ADD ANY ISOLATED SHOWERS OR
THUNDERSTORMS AT THIS TIME. HOWEVER WILL NEED TO CONTINUE TO MONITOR
THE HIGHER MOUNTAIN TERRAIN NEAR THE VA BORDER FOR ANY DEVELOPMENT.
THE AREA OF SHOWERS AND THUNDERSTORMS OVER WESTERN INDIANA IS AHEAD
OF NEARLY STATIONARY WARM FRONTAL BOUNDARY THAT REPRESENTS THE
LEADING EDGE OF 70 PLUS DEWPOINT TEMPERATURES OVER IL...MO AND
WESTERN KY. SATELLITE...RADAR AND LIGHTNING TRENDS ALL SHOW
CONTINUING WEAKENING OF CONVECTION OVER INDIANA. THE SHORT RANGE RAP
AND HRRR ALSO SHOW CONTINUING DECAY OF THIS CONVECTION...AND ONLY
IMPACT ON OUR AREA WILL BE SOME INCREASE IN HIGH LEVEL CLOUDS. QUITE
DRY HERE IN EASTERN KY EARLY THIS AFTERNOON WITH DEWPOINTS AS LOW AS
THE LOWER 50S. WILL BE UPDATING NDFD FOR LATEST OBSERVATIONAL TRENDS.
UPDATE ISSUED AT 935 AM EDT SAT JUL 12 2014
NDFD AND ASSOCIATED PRODUCTS HAVE BEEN UPDATED FOR LATEST
OBSERVATIONAL TRENDS. THE MENTION OF EARLY MORNING VALLEY FOG HAS
BEEN REMOVED FROM THE ZFP.
UPDATE ISSUED AT 748 AM EDT SAT JUL 12 2014
HOURLY GRIDS WERE FRESHENED UP BASED ON RECENT OBSERVATIONS AND
SATELLITE IMAGERY. OTHERWISE...THE CURRENT FORECAST IS ON TRACK. SFC
AND UPPER LEVEL RIDGING SHOULD BRING TO A WARM AND DRY DAY TO ALL
AREAS ONCE VALLEY FOG LIFTS AND DISSIPATE.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 405 AM EDT SAT JUL 12 2014
EARLY THIS MORNING...UPPER LEVEL RIDGING WAS CENTERED OVER THE PLAINS
STATES WITH RIDGING EAST INTO THE SOUTHEASTERN STATES AND ALSO WEST
AND NORTHWEST INTO THE DESERT SOUTHWEST AND NORTH INTO PARTS OF THE
INTER MOUNTAIN WEST. AN UPPER LEVEL LOW WAS CENTERED JUST WEST OF THE
HUDSON BAY REGION WITH SOME BROAD TROUGHING TO ITS SOUTH ACROSS PARTS
OF CENTRAL CANADA SOUTH INTO THE NORTH CENTRAL US AND NORTHERN GREAT
LAKES REGIONS. AT THE SFC...HIGH PRESSURE WAS CENTERED ALONG THE MID
ATLANTIC SEABOARD WITH THE RIDGE AXIS EXTENDING SOUTH INTO THE
SOUTHEASTERN STATES. EXTENDING SOUTH FROM SFC LOW PRESSURE OVER
CENTRAL CANADA WAS A COLD FRONT THAT DOWN SOUTH AND SOUTHWEST ACROSS
WESTERN LAKE SUPERIOR AND THEN FURTHER WEST AND SOUTHWEST INTO THE
NORTHERN PLAINS. MEANWHILE...THE REMNANTS OF A BOUNDARY THAT CROSSED
THE AREA EARLIER IN THE WEST EXTENDED FROM SFC LOW PRESSURE NEAR THE
LEE OF THE ROCKIES FIRST NORTH AND NORTHEAST INTO THE MID MS VALLEY
AND THEN SOUTH AND THEN SOUTHEAST ACROSS PARTS OF THE SOUTHEASTERN
STATES.
EARLY TODAY...MAINLY RIVER VALLEY FOG SHOULD GRADUALLY LIFT AND BEGIN
TO DISSIPATE WITHIN AND HOUR OR TWO AFTER SUNRISE. OVERALL...VIS
REDUCTIONS WITH THIS SHOULD BE LESS THAN ON FRIDAY AM.
TODAY AND TONIGHT...THE UPPER LEVEL LOW WILL DROP SOUTH AND THEN
SOUTHEAST INTO NORTHWESTERN ONTARIO BY DAWN ON SUNDAY. THIS WILL PUSH
THE INITIAL SFC COLD FRONT EAST MORE QUICKLY THAN SOUTH A RIDGING WILL
REMAIN IN PLACE FROM THE ROCKIES INTO THE SOUTHERN PLAINS AND
SOUTHEASTERN CONUS. THE SOUTHWESTERN PART OF THE BOUNDARY SHOULD
EVENTUALLY MERGE WITH THE OLD BOUNDARY ACROSS THE CENTRAL PLAINS AS A
SFC WAVE WORKS NORTHEAST FROM THE CENTRAL CONUS AND INTO THE GREAT
LAKES. THIS WILL ALSO SEND WHAT IS LEFT OF THE OLD BOUNDARY NORTHEAST
ACROSS THE AREA AS A WARM FRONT TONIGHT. THIS WILL USHER IN A RETURN
OF MUCH DEEPER MOISTURE LATE TONIGHT AND ESPECIALLY INTO SUNDAY.
THE UPPER LEVEL LOW SHOULD MOVE FURTHER SOUTH BY THE END OF TH PERIOD
AND LEAD TO FURTHER HEIGHT FALLS ACROSS THE GREAT LAKES AND LOCALLY.
DURING THIS PERIOD THE INITIAL COLD FRONT SHOULD REACH NEAR THE OH
RIVER BY THE END OF THE PERIOD. HOWEVER...A MORE POTENT FRONT WILL
ALSO DROP SOUTH INTO THE GREAT LAKES AND MIDWEST ALSO BY THE END OF
THE PERIOD. THE MOST ACTIVE WEATHER WITH THE LOWERING HEIGHTS AND
SHORTWAVES WORKING THROUGH THE FLOW SHOULD BE AFTER THE PERIOD. HOWEVER...
WITH INCREASING MOISTURE AND SOME SFC HEATING THE ATMOSPHERE WILL
BEGIN TO BECOME UNSTABLE ON SUNDAY AHEAD OF THE SLOW MOVING BOUNDARY.
THERE WILL ALSO BE SOME SLIGHT HEIGHT FALLS DURING SUNDAY AFTERNOON
AS WELL. SOME ISOLATED TO POSSIBLY SCATTERED CONVECTION IS
ANTICIPATED AT THAT POINT. SHEAR SHOULD BE GREATEST ACROSS THE FAR
NORTHWEST...BUT MODELS DIFFER IN THE DEGREE OF INSTABILITY. SPC HAS
PLACE THE FAR NORTHWEST CWA IN A SLIGHT RISK OF SEVERE THUNDERSTORMS
AND PENDING ON CONVECTIVE EVOLUTION THE SOUTHWEST END OF A PREFRONTAL
LINE OF STORMS MIGHT REACH THE FAR NORTHWEST CWA LATE IN THE PERIOD.
THE DEGREE OF INSTABILITY IN PLACE ACROSS THE NORTHWEST PART OF THE
AREA...WHEN A LINE POSSIBLY ARRIVES LATE ON SUNDAY WOULD DETERMINE
WHETHER ANY STRONG TO SEVERE STORMS WITH GUSTY WINDS BEING THE MAIN
THREAT WOULD OCCUR. IT WOULD SEEM HOWEVER IF ENOUGH INSTABILITY CAN
BE REALIZED THAT MONDAY WOULD BE THE DAY DURING THE ENTIRE FORECAST
PERIOD WHERE STRONG TO SEVERE THUNDERSTORMS WOULD BE MOST
PROBABLE...AHEAD OF A SHARPER FRONT AND STRONGER MID LEVEL SYSTEM.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 326 AM EDT SAT JUL 12 2014
THE MODELS WERE IN GENERAL AGREEMENT IN THE EXTENDED PERIOD. THE
WEATHER OF THE UPCOMING WEEK WILL FEATURE WIDESPREAD SHOWERS AND
STRONG TO POSSIBLY SEVERE THUNDERSTORMS SUNDAY NIGHT THROUGH MONDAY
EVENING. THE MODEL DATA ALL SUGGEST DECENT INSTABILITY...GOOD LOW
LEVEL MOISTURE FEED FROM THE SOUTH...AND SOME WIND SHEAR DURING THE
DAY ON MONDAY. THE TRIGGER FOR ALL THE EXPECTED SHOWER AND STORM
ACTIVITY WILL BE A SLOW MOVING AND FAIRLY POTENT COLD FRONT. SHOWERS
AND STORMS WILL BE MOST NUMEROUS AND STRONGEST DURING FRONTAL PASSAGE
MONDAY AFTERNOON AND EVENING...SHOULD THE LATEST MODEL SOLUTIONS PAN
OUT THAT IS. THE FRONT IS EXPECTED TO STALL OUT ALONG THE SPINE OF
THE APPALACHIANS MONDAY NIGHT...KEEPING A CHANCE OF RAIN IN THE
FORECAST THROUGH THE END OF THE DAY ON TUESDAY.
MUCH COOLER AND DRIER AIR WILL FILTER INTO THE REGION BEHIND THE
FRONT BEGINNING TUESDAY NIGHT. THIS NEW AIR MASS WILL CONTRIBUTE TO
WELL BELOW NORMAL TEMPERATURES FOR THIS TIME OF YEAR...WITH HIGHS
TOPPING OUT IN THE VERY COMFORTABLE MID TO UPPER 70S TUESDAY
WEDNESDAY AND THURSDAY. OVERNIGHT LOWS TUESDAY NIGHT AND WEDNESDAY
NIGHT SHOULD EASILY DROP INTO THE MID TO UPPER 50S ACROSS THE AREA
BENEATH PARTLY CLOUD SKIES. THE MERCURY SHOULD BE ABLE TO CLIMB A
BIT HIGHER TO END THE WEEK AS THE AIRMASS MODIFIES...WITH HIGHS
REACHING THE LOWER 80S ON FRIDAY. AFTER A DRY PERIOD DURING THE
MIDDLE OF THE WEEK...ANOTHER SHOT OF RAIN MIGHT BE IN THE OFFING
TOWARD THE END OF THE WEEK...AS A WEATHER SYSTEM PASSES BY TO OUR
SOUTH THURSDAY NIGHT THROUGH FRIDAY NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 116 PM EDT SAT JUL 12 2014
SCATTERED CUMULUS AROUND 5K TO 6K FEET WITH LIGHT WINDS CAN BE
EXPECTED THIS AFTERNOON AS HIGH PRESSURE CONTINUES TO CONTROL THE
LOCAL WEATHER. ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
REMAIN JUST OUTSIDE OF THE FORECAST AREA THIS AFTERNOON IN THE HIGHER
TERRAIN OF SW VA...TN AND NC. THERE WAS LESS FOG THIS MORNING THAN
YESTERDAY MORNING AND EXPECT THAT TREND TO CONTINUE. AS SUCH WILL
LEAVE FOG OUT OF TAFS FOR THIS FORECAST. VFR CONDITIONS WILL PREVAIL
AGAIN ON SUNDAY...BUT SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE BY
SUNDAY NIGHT AHEAD OF A COLD FRONT DROPPING SOUTH ACROSS OH AND
INDIANA.
.JKL WATCHES/WARNINGS/ADVISORIES...
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...JP
LONG TERM...AR
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
425 PM EDT SAT JUL 12 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 422 PM EDT SAT JUL 12 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A DEEP MID/UPPER LEVEL LOW FROM
WRN HUDSON BAY INTO NRN MANITOBA. A LINE OF SHRA/TSRA THROUGH SRN
MANITOBA WAS ASSOCIATED WITH A PROMINENT SHORTWAVE TROUGH AND COLD
FRONT NEARING WINNIPEG. FARTHER SOUTH...A WEAKER SHRTWV FROM ERN MN
INTO WRN WI COMBINED WITH MORE ABUNDANT MOISTURE (PWAT VALUES AROUND
1.5 INCH) SUPPORTED AN AREA OF SHRA AND ISOLD TSRA FROM SE MN INTO
CNTRL AND NRN WI. CONVERGENCE ALON LAKE SUPERIOR AND LAKE MICHIGAN
LAKE BREEZE BOUNDARIES WHERE MLCAPE HAS CLIMBED TO NEAR 1K J/KG HAS
TRIGGERED ISOLD ISOLD SHRA/TSRA FROM FAR NW DELTA COUNTY INTO NRN
SCHOOLCRAFT COUNTY.
TONIGHT...EXPECT ADDITIONAL SHRA/TSRA DEVELOPMENT ALONG THE LAKE
BREEZE BOUNDARIES INLAND FROM CNTRL INTO ERN UPPER MI INTO THIS
EVENING TIL THE LOSS OF DAYTIME HEATING. THERE IS MORE UNCERTAINTY
REGARDING THE SHRA/TSRA OVER NRN WI AS SEVERAL HIGH RES MODELS
SUGGEST THAT THEY MAY EXPAND INTO SRN UPPER MI AND POSSIBLE TOWARD
MQT/P53 AS THE WI SHRTWV ADVANCES TO THE EAST.
HOWEVER...RADAR/SATELLITE TRENDS WOULD FAVOR KEEPING HIGHER
COVERAGE/POPS MAINLY OVER THE FAR S/SE CWA. ADDITIONAL SHRA AND
POSSIBLY ISOLD THUNDER WILL BE POSSIBLE AS THE MANITOBA FRONT/SHRTWV
MOVE INTO UPPER MI OVERNIGHT. HOWEVER...SINCE THE PCPN FOCUS ARRIVES
WHEN MUCAPE HAS DIMINISHED TO 400 J/KG OR LESS...ONLY SLIGHT
CHANCE POPS WERE INCLUDED.
SUNDAY...AFTER ANY LINGERING SHRA DEPART FROM THE FAR ERN CWA
EARLY...BREEZY AND COOLER WEATHER IS EXPECTED BEHIND THE COLD FRONT.
HOWEVER...WITH WNW WINDS AND 850 MB TEMPS IN THE 6C-8C RANGE...MAX
READINGS SHOULD STILL CLIMB INTO THE UPPER 60S TO LOWER 70S FROM NW
TO SE.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 422 PM EDT SAT JUL 12 2014
MAIN CONCERNS DURING THIS TIME PERIOD WILL BE RAIN CHANCES MONDAY
AND TUESDAY WITH COOLER THAN NORMAL TEMPERATURES THROUGH MUCH OF THE
WORK WEEK.
SUNDAY NIGHT THROUGH TUESDAY...THE MAIN SURFACE LOW WILL BE CENTERED
OVER JAMES BAY AROUND 00Z/14 WHILE THE MAIN UPPER LEVEL
ENERGY/CLOSED LOW WILL REMAIN OVER THE ONTARIO/MANITOBA BORDER. THIS
WILL PLACE THE UPPER PENINUSLA AND MUCH OF THE EASTERN HALF OF THE
COUNTRY IN BROAD UPPER LEVEL TROUGHING. THE BREAK IN PRECIPITATION
WILL CONTINUE SUNDAY NIGHT AS A BRIEF WEDGE OF DRY AIR PUSHES
THROUGH THE CWA. BY LATE SUNDAY NIGHT...DEEPER MOISTURE...ASSOCIATED
WITH THE UPPER LEVEL 500MB LOW IN SOUTHERN CANADA...WILL APPROACH
THE FAR WESTERN U.P. IN ADDITION...A SURFACE TROUGH WILL EXTEND
SOUTHWESTWARD FROM THE PARENT SURFACE LOW INTO NORTHERN MN. THIS
WILL HELP TO KEEP THE BETTER FORCING TO THE NORTHWEST OF THE U.P.
SUNDAY NIGHT. THE SURFACE LOW WILL SHIFT FROM JAMES BAY 12Z/14 TO
CENTRAL QUEBEC BY 18Z/15. THIS WILL ALLOW THE SURFACE TROUGH TO PUSH
ACROSS THE U.P. THROUGH THE DAY MONDAY AND INTO THE LOWER GREAT
LAKES MONDAY NIGHT. AT THE SAME TIME THE UPPER LEVEL 500MB CLOSED
LOW OVER NORTHERN MN WILL SWEEP ACROSS THE U.P. AND REACH THE
QUEBEC/SOUTHERN ONTARIO BORDER BY 18Z/15. AS FAR AS PRECIP
GOES...HAVE KEPT THE TREND OF INCREASING POPS THROUGH THE DAY
MONDAY...DUE LARGELY TO THE CONVERGENCE ALONG THE SURFACE
TROUGH/INCREASED 1000-500MB RH/VORT MAX PRESSING THROUGH THE U.P.
ALONG WITH DIURNAL HEATING.
ONCE THE BETTER FORCING EXITS THE REGION MONDAY
EVENING...PRECIPITATION CHANCES WILL SLOWLY DIMINISH. STILL KEPT
ONGOING CHANCES OF SHOWERS IN THE FORECAST THROUGH TUESDAY AS THE
UPPER LEVEL 500MB AND INCREASED MOISTURE LINGERS ACROSS THE AREA.
THERE ARE SOME DIFFERENCES IN THE MODELS...WITH THE GFS HAS BEEN
MORE PROGRESSIVE WITH THE UPPER LEVEL LOW WHILE THE EC/GEM KEEP THE
UPPER LEVEL LOW OVER THE U.P. THROUGH TUESDAY AFTERNOON BEFORE
EXITING THE CWA BY 00Z/16. THE 12Z RUN OF THE GFS IS COMING INTO
BETTER AGREEMENT WITH THE EC/GEM LENDING MORE SUPPORT TO THESE
SOLUTIONS. TUESDAY WILL LIKELY END UP BEING THE COOLEST DAY OF THE
WEEK WITH THE UPPER LEVEL LOW PASSING THROUGH THE AREA PULLING 850MB
TEMPS DOWN TO AROUND 4 TO 5C. HIGHS WILL STRUGGLE TO GET INTO THE
60S ACROSS MANY AREAS...WHILE NORMAL HIGHS THIS TIME OF YEAR ARE
AROUND 77 DEGREES.
TUESDAY NIGHT THROUGH THE REST OF THE EXTENDED...VERY QUIET WEATHER
EXPECTED THROUGH THIS TIME PERIOD WITH SLOWLY MODERATING
TEMPERATURES THROUGH THE UPCOMING WEEKEND AS UPPER LEVEL RIDGING
BEGINS TO BUILD BACK INTO THE REGION. AT THE SURFACE...BROAD HIGH
PRESSURE WILL BUILD ACROSS THE UPPER GREAT LAKES REGION AND LINGER
THROUGH FRIDAY NIGHT. THE GFS KEEPS THE HIGH POSITIONED OVER THE
AREA THROUGH SATURDAY WHILE THE EC SLIDES THE HIGH
EASTWARD...ALLOWING A SURFACE LOW AND UPPER LEVEL TROUGH ALONG WITH
INCREASED MOISTURE TO PUSH INTO THE FAR WESTERN CWA. WITH MODEL
DIFFERENCES WILL STICK WITH A CONSENSUS OF THE MODELS FOR
SATURDAY..WHICH BRINGS A CHANCE OF SHOWERS TO THE FAR WESTERN U.P.
DURING THE AFTERNOON AND EVENING HOURS SATURDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 144 PM EDT SAT JUL 12 2014
EXPECT VFR CONDITIONS THROUGH THE FCST PERIODS WITH SCT DIURNAL
SHRA/TSRA REMAINING SOUTH OF THE TAF SITES LATE THIS AFTERNOON AND
EVENING. WITH A STRONG FRONT MOVING THROUGH THE UPPER MI LATE
TONIGHT...W WINDS MAY GUST OVER 20 KTS AT KCMX AS THE FRONT MOVES
THROUGH. GUSTY WNW WINDS WILL ALSO DEVELOP AT IWD/SAW WITH DAYTIME
HEATING/MIXING BY LATE SUN MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 422 PM EDT SAT JUL 12 2014
SOUTHWEST WINDS THIS EVENING WILL SHIFT SHARPLY TO THE WEST LATE
TONIGHT AS A COLD FRONT ARRIVES. THERE MAY BE SOME WIND GUSTS UP
TO 25 KTS AT LEAST BRIEFLY LATE TONIGHT OVER WEST AND NORTH CENTRAL
LK SUPERIOR BEHIND THE FRONT. AREAS OF FOG ARE CURRENTLY OVER LAKE
SUPERIOR WILL DISSIPATE ON SUNDAY IN WAKE OF THE STRONGER FRONT AS
STRONG DRY ADVECTION TAKES OVER. EXPECT NORTHWEST WINDS TO 20 KTS AT
TIMES INTO EARLY THIS WEEK IN WAKE OF THE COLD FRONT AND AS HIGH
PRESSURE BUILDS OVER THE NORTHERN PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KEC
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
419 PM EDT SAT JUL 12 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 418 PM EDT SAT JUL 12 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A DEEP MID/UPPER LEVEL LOW FROM
WRN HUDSON BAY INTO NRN MANITOBA. A LINE OF SHRA/TSRA THROUGH SRN
MANITOBA WAS ASSOCIATED WITH A PROMINENT SHORTWAVE TROUGH AND COLD
FRONT NEARING WINNIPEG. FARTHER SOUTH...A WEAKER SHRTWV FROM ERN MN
INTO WRN WI COMBINED WITH MORE ABUNDANT MOISTURE (PWAT VALUES AROUND
1.5 INCH) SUPPORTED AN AREA OF SHRA AND ISOLD TSRA FROM SE MN INTO
CNTRL AND NRN WI. CONVERGENCE ALON LAKE SUPERIOR AND LAKE MICHIGAN
LAKE BREEZE BOUNDARIES WHERE MLCAPE HAS CLIMBED TO NEAR 1K J/KG HAS
TRIGGERED ISOLD ISOLD SHRA/TSRA FROM FAR NW DELTA COUNTY INTO NRN
SCHOOLCRAFT COUNTY.
TONIGHT...EXPECT ADDITIONAL SHRA/TSRA DEVELOPMENT ALONG THE LAKE
BREEZE BOUNDARIES INLAND FROM CNTRL INTO ERN UPPER MI INTO THIS
EVENING TIL THE LOSS OF DAYTIME HEATING. THERE IS MORE UNCERTAINTY
REGARDING THE SHRA/TSRA OVER NRN WI AS SEVERAL HIGH RES MODELS
SUGGEST THAT THEY MAY EXPAND INTO SRN UPPER MI AND POSSIBLE TOWARD
MQT/P53 AS THE WI SHRTWV ADVANCES TO THE EAST.
HOWEVER...RADAR/SATELLITE TRENDS WOULD FAVOR KEEPING HIGHER
COVERAGE/POPS MAINLY OVER THE FAR S/SE CWA. ADDITIONAL SHRA AND
POSSIBLY ISOLD THUNDER WILL BE POSSIBLE AS THE MANITOBA FRONT/SHRTWV
MOVE INTO UPPER MI OVERNIGHT. HOWEVER...SINCE THE PCPN FOCUS ARRIVES
WHEN MUCAPE HAS DIMINISHED TO 400 J/KG OR LESS...ONLY SLIGHT
CHANCE POPS WERE INCLUDED.
SUNDAY...AFTER ANY LINGERING SHRA DEPART FROM THE FAR ERN CWA
EARLY...BREEZY AND COOLER WEATHER IS EXPECTED BEHIND THE COLD FRONT.
HOWEVER...WITH WNW WINDS AND 850 MB TEMPS IN THE 6C-8C RANGE...MAX
READINGS SHOULD STILL CLIMB INTO THE UPPER 60S TO LOWER 70S FROM NW
TO SE.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 328 AM EDT SAT JUL 12 2014
NAM SHOWS A CLOSED 500 MB LOW OVER SOUTH CENTRAL CANADA 12Z SUN WITH
A 500 MB TROUGH DIGGING INTO THE GREAT LAKES REGION. UPPER AIR
PATTERN AMPLIFIES OVER THE AREA 12Z MON WITH THE LOW MOVING OVER THE
AREA ON MON. AS THE LOW MOVES OVER THE AREA ON MON...EXPECT SOME
INSTABILITY SHOWERS TO BREAK OUT WITH THE HIGHEST POPS DURING THE
PEAK DIURNAL HEATING. NAM SHOWS SOME DEEPER MOISTURE AND 850-500 MB
Q-VECTOR CONVERGENCE MOVING THROUGH THE AREA ON MON INTO MON NIGHT.
WILL HAVE SOME SMALL CHANCE POPS IN FOR THE ERN CWA SUN MORNING AND
THEN GO DRY FOR SUN AFTERNOON AND SUNDAY EVENING. WITH APPROACH OF
THE UPPER LEVEL LOW ON MON...WILL HAVE POPS INCREASING TO LIKELY IN
A FEW PLACES MON WITH PEAK DIURNAL HEATING HAVING THE HIGHEST POPS
IN THE AFTERNOON. WITH LOSS OF DIURNAL HEATING MON NIGHT...HAVE POPS
DECREASING BACK TO CHANCE TO SLIGHT CHANCES. OVERALL...DID NOT MAKE
TOO MANY CHANGES TO THE GOING FORECAST. TEMPERATURES WILL BEGIN THE
COOLING TREND THIS FORECAST PERIOD AND LOWERED HIGHS A BIT FOR SUN
THROUGH MON NIGHT.
IN THE EXTENDED...GFS AND ECMWF SHOW A DEEP 500 MB TROUGH AND CLOSED
LOW OVER THE ERN HALF OF NORTH AMERICA WITH VERY COLD TEMPERATURES
OVER THE AREA 12Z TUE. THE TROUGH REMAINS NEARLY STATIONARY INTO THU
BEFORE PATTERN MODIFICATION TAKES PLACE WITH THE TROUGH AND
AMPLIFICATION BREAKING DOWN. A RIDGE MOVES INTO THE ROCKIES 12Z FRI.
WHAT THIS WILL MEAN IS THE COOL CONDITIONS WILL CONTINUE FOR MOST OF
THE FORECAST PERIOD WITH A SLOW MODERATION IN TEMPERATURES. SFC
HIGH PRESSURE REMAINS IN CONTROL OF THE WEATHER AND LOOKS COOL AND
DRY FOR THE MOST PART. WILL KEEP SOME SMALL POPS IN FOR TUE WITH
DEPARTING UPPER LOW IN THE AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 144 PM EDT SAT JUL 12 2014
EXPECT VFR CONDITIONS THROUGH THE FCST PERIODS WITH SCT DIURNAL
SHRA/TSRA REMAINING SOUTH OF THE TAF SITES LATE THIS AFTERNOON AND
EVENING. WITH A STRONG FRONT MOVING THROUGH THE UPPER MI LATE
TONIGHT...W WINDS MAY GUST OVER 20 KTS AT KCMX AS THE FRONT MOVES
THROUGH. GUSTY WNW WINDS WILL ALSO DEVELOP AT IWD/SAW WITH DAYTIME
HEATING/MIXING BY LATE SUN MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 418 PM EDT SAT JUL 12 2014
SOUTHWEST WINDS THIS EVENING WILL SHIFT SHARPLY TO THE WEST LATE
TONIGHT AS A COLD FRONT ARRIVES. THERE MAY BE SOME WIND GUSTS UP
TO 25 KTS AT LEAST BRIEFLY LATE TONIGHT OVER WEST AND NORTH CENTRAL
LK SUPERIOR BEHIND THE FRONT. AREAS OF FOG ARE CURRENTLY OVER LAKE
SUPERIOR WILL DISSIPATE ON SUNDAY IN WAKE OF THE STRONGER FRONT AS
STRONG DRY ADVECTION TAKES OVER. EXPECT NORTHWEST WINDS TO 20 KTS AT
TIMES INTO EARLY THIS WEEK IN WAKE OF THE COLD FRONT AND AS HIGH
PRESSURE BUILDS OVER THE NORTHERN PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...07
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
156 PM EDT SAT JUL 12 2014
.AVIATION...
//DISCUSSION...
VFR CONDITIONS WILL HOLD THROUGHOUT THE AFTERNOON HOURS AS RIDGING
HOLDS TIGHT OVER SOUTHEASTERN MICHIGAN. FOCUS FOR THIS SET OF TAFS
WAS TO REFINE TIMING OF PRECIPITATION AND THUNDERSTORMS. QUITE A BIT
OF UNCERTAINTY REMAINS. FIRST THING TO WATCH FOR WILL BE SHOWER
ACTIVITY POSSIBLY RELEASING OFF OF THE LEE OF LAKE MICHIGAN SURFACE
TROUGH...MAKING A RUN FOR THE TRI CITIES LATE THIS AFTERNOON. IN
ADDITION...LEAD PUSH OF WARM AIR ADVECTION WILL LEAD TO A LOW CHANCE
FOR A SHOWER OR THUNDERSTORM JUST ABOUT ANYWHERE OVER SOUTHEASTERN
MICHIGAN DURING THE SAME TIME. CONFIDENCE REMAINS TOO LOW TO INCLUDE
IN FORECAST. BEST FORCING AND POTENTIAL FOR SHOWERS AND
THUNDERSTORMS WILL COME LATER TONIGHT AS UPPER LEVEL FORCING FINALLY
SETTLE INTO THE REGION. THERE REMAINS SOME TIMING DIFFERENCES...BUT
A COUPLE OF HOURS. LATEST FEELING IS THAT MAJORITY OF UPSTREAM
CONVECTION WILL SLIDE THROUGH SOUTHEASTERN MICHIGAN BETWEEN 5-10Z.
THE THUNDERSTORM ACTIVITY IS EXPECTED TO BEGIN ACROSS THE SAGINAW
VALLEY...THEN SETTLE SOUTHWARD TOWARDS THE OHIO/MICHIGAN BORDER.
//DTW THRESHOLD THREATS...
* THERE IS HIGH CONFIDENCE THAT THUNDERSTORMS WILL OCCUR OVERNIGHT.
* THERE IS HIGH CONFIDENCE THAT CEILINGS WILL FALL BELOW 5000 FT
OVERNIGHT.
&&
.PREV DISCUSSION...ISSUED 1121 AM EDT SAT JUL 12 2014
UPDATE...
CLEANED UP THE GRIDS THIS MORNING TO ACCOUNT FOR LACK OF SKY
FRACTION EARLY. PUSHED A MORE OPTIMISTIC FORECAST INTO THE
AFTERNOON...ALTHOUGH HIGH CLOUD IS CLOSING IN FAST. OFF OF THE
WARM START...INCREASED MAXIMUM TEMPERATURES A DEGREE OR TWO.
RECENT HIRES..CONVECTION ALLOWING MODELS INCLUDING ITERATIONS OF
THE HRRR AND MEMBERS OF THE IN-HOUSE HI-RESOLUTION WRF ENSEMBLE
ARE PORTRAYING HIGH CERTAINTY THAT PRECIPITATION AND SHOWER/TSTORM
ACTIVITY WILL REMAIN WELL WEST OF THE CWA THROUGHOUT THE MAJORITY
OF THE AFTERNOON...THROUGH 6PM. BULLISH NAM IS REALLY ON AN ISLAND
WITH REGARDS TO BRINGING QPF INTO THE AREA BEFORE 00Z. FORECASTED
CAPE FROM PLAN VIEW IMAGES SHOW MODEST INSTABILITY BECOMING
BOTTLED UP THIS AFTERNOON ACROSS FAR WESTERN PORTIONS OF LOWER
PENINSULA CENTERED ALONG A WEAK LEE OF LAKE MICHIGAN SURFACE
TROUGH. CONTINUED ANTICYCLONIC CURVATURE SUPPORTS A SHORTWAVE
RIDGING FEATURE AMPLIFYING DOWNSTREAM OF THE INBOUND BULLDOZER
TROUGH WHICH WILL ACTUALLY SUPPORT SUBSIDENCE OR SYNOPTIC SCALE
DESCENT. SHORTWAVE ENERGY WILL ARRIVE AND PASS OVER THE AREA BETWEEN
6-8PM...WHICH WILL BE COLLOCATED WITH AN INCREASE IN TANGIBLE
LOWER TROPOSPHERIC HUMIDITY AND ENTRY LEVEL CAPE. IT IS ALONG THIS
LEAD EDGE AND THE RICH THETAE ADVECTION BURST THAT SHOWERS AND A
POSSIBLE THUNDERSTORM COULD ARRIVE FOR THE EARLY EVENING.
OTHERWISE...EXPECTING MUCH OF THIS TO STRUGGLE. NO STRONG OR
SEVERE WEATHER EXPECTED THROUGH THIS EVENING.
STILL EXPECTING THE CATEGORICAL PRECIPITATION CHANCES TO INCREASE
LATE TONIGHT...POSSIBLY AS LATE AS 8 OR 9Z. THIS WILL OCCUR IN
COMBINATION OF UPPER LEVEL FLOW BECOMING CYCLONIC IN TIME DUE TO
THE ARRIVAL OF THE INBOUND DIGGING CLOSED LOW AS WELL AS
UPSTREAM CONVECTION/FRESH LOW LEVEL JET RESPONSE SLIDING OVER FAR
SOUTHERN LOWER MICHIGAN. WILL INVESTIGATE THIS FOR THE AFTERNOON
PACKAGE.
PREV DISCUSSION...ISSUED 351 AM EDT SAT JUL 12 2014
SHORT TERM...TODAY AND TONIGHT
THE INTERACTION OF A STRONG MID/UPPER LEVEL TROUGH DIGGING INTO THE
GREAT LAKES AND A RESIDUAL STATIONARY BOUNDARY OVER THE OHIO VALLEY
EXTENDING WESTWARD TO THE MISSISSIPPI WILL MAKE FOR AN ACTIVE
STRETCH OF WEATHER THIS WEEKEND. ADDING TO THE COMPLEXITY WILL BE
SEVERAL SHORTWAVES EMBEDDED WITHIN BOTH FEATURES. AS THE SYSTEM GETS
DEEPER INTO THE HIRES RUNS WE CONTINUE TO GET A BETTER FEEL FOR
HOW THE EVENT LOOKS TO PLAY OUT. TODAY WILL BE A PERIOD OF
TRANSITION FROM THE DRY AND STABLE AIRMASS BROUGHT TO US BY THE
EXITING HIGH PRESSURE SYSTEM. THE INITIAL SURGE OF JET ENERGY
EXITING THE TROUGH WILL STAY TO THE NORTH OVER LAKE SUPERIOR AS IT
ROUNDS THE RIDGE STILL IN PLACE AS WE START THE DAY OFF. SEMBLANCE
OF A LOW AMPLITUDE SHORTWAVE RIDGE IN THE NEARLY ZONAL FLOW OVER THE
MIDWEST SHOULD ADD TO THE ALREADY STABLE/WARM MID LEVELS HELPING TO
KEEP THE AREA DRY. THE LEAD EDGE OF THE THETA E PLUME IS ENTERING
THE AREA AT PRESS TIME ON THE HEALS OF A SHORTWAVE SEEN ON WATER
VAPOR EXITING LAKE HURON. THIS WILL MERELY START THE SATURATION
PROCESS IN THE COLUMN WHICH HAD A PWAT OF ONLY 0.73 INCHES IN THE
00Z DTX SOUNDING FROM FRIDAY EVENING. MODEL SOUNDINGS SHOW THIS
JUMPING TO ABOVE 1.3 INCHES BY 12Z THIS MORNING AND CLOSE TO 1.8
INCHES BY THIS EVENING.
A STRONGER SHORTWAVE EMBEDDED IN THE SOUTHERN STREAM OF THE JET WILL
UNDERGO CYCLOGENESIS AS IT TRACKS ALONG THE AFOREMENTIONED
STATIONARY BOUNDARY TARGETING SE MI AROUND 00Z THIS EVENING. THIS
WILL REALLY ENHANCE THE MOISTURE FLUX INTO SOUTHERN MI WITH DEEP
LAYER OF SW FLOW DEVELOPING AHEAD OF THIS LOW. THE LOW WILL REACH US
CO-LOCATED WITH UPPER LEVEL DIFFLUENCE ALOFT...RIGHT ENTRANCE REGION
OF THE JET STREAK...NOCTURNAL LL JET AND THE STRONGEST INSTABILITY
GRADIENT. THIS SHOULD YIELD THUNDERSTORMS OVER MOST OF THE AREA
OVERNIGHT. BEST TIME FOR STORMS LOOKS TO BE AROUND 06-12Z TONIGHT. A
FEW SHOWERS/THUNDERSTORMS MAY POP UP AS EARLY AS 21Z MAINLY ACROSS
THE WESTERN COUNTIES AS INSTABILITY AND MOISTURE BEGIN TO SPILL INTO
THE AREA ON THE LEADING EDGE OF THE WEAKER THETA E GRADIENT. WE
COULD ALSO SEE SOME ACTION ACROSS THE FAR SOUTH AS THE COMPLEX SET
TO DEVELOP ON TONIGHTS LL JET WORKS ALONG THE STATIONARY FRONT. THE
TREND FOR THESE STORMS SHOULD BE TO WEAKEN AND FADE OUT AS THEY LOSE
THE BATTLE TO STABLE AIR BUT COULD CLIP THE AREA.
SPC HAS THE SLIGHT RISK AREA TO OUR WEST BUT DOES COVER A PORTION OF
SW LOWER MI. THIS SEEMS FAIR WITH THE TREND IN THE MODELS TO KEEP
THE LL JET FROM ENTERING SE MI TIL POTENTIALLY 09Z. WILL MONITOR
TRENDS IN TIMING THE MAIN FEATURE AND HOW WELL DEVELOPED THE SYSTEM
GETS TONIGHT. CURRENTLY THINKING IS THAT FEW STRONG STORMS COULD
DEVELOP WITH A WIND AND HAIL THREAT OVERNIGHT...BUT HEAVY RAIN WILL
BE A BIGGER THREAT WITH SUCH A MOIST AIRMASS ADVECTING IN.
LONG TERM...
SUNDAY GETS A BIT TRICKY AS THERE ARE VARYING MODEL SOLUTIONS WITH A
FAIRLY DRY GFS/ECMWF/GEM SOLUTION WHILE THE NAM HOLDS ON TO ABUNDANT
QPF. WHILE MODEL CONSENSUS BY ITSELF IS NOT ENOUGH TO THROW OUT THE
NAM...UPPER LEVEL FEATURES LEND CREDENCE TO THIS SOLUTION AS A
PRONOUNCED 700 MB DRY SLOT ADVECTS IN FROM THE WEST WHILE THE UPPER
LEVEL JET SINKS SOUTH...GIVING THE BEST MOISTURE AND DYNAMICS TO
AREAS ACROSS THE SOUTH AND EAST. THIS IS ALSO IN LINE WITH THE MOST
RECENT SPC DAY 2 OUTLOOK WHICH HAS PUSHED THE SLIGHT RISK JUST SOUTH
OF OUR CWA WHICH SEEMS REASONABLE GIVEN THE AFOREMENTIONED FACTORS.
THE DRY SLOT AND SOME SUNSHINE WILL ALLOW TEMPERATURES TO GET INTO
THE LOWER 80S ACROSS SOUTHEAST MICHIGAN SUNDAY AFTERNOON.
THIS DRY AIR BECOMES VERY PRONOUNCED SUNDAY NIGHT WITH THE LOSS OF
DAYTIME HEATING TAKING AWAY ANY BOOST FROM INCOMING SOLAR RADIATION.
POPS SUNDAY NIGHT WILL MAINLY BE CONFINED TO THE EVENING HOURS WITH
MAINLY DRY WEATHER EXPECTED LATER IN THE EVENING INTO THE OVERNIGHT
HOURS. THE DRIER COOLER AIR WILL ALLOW SOME RADIATIONAL
COOLING...PUSHING NIGHTTIME LOWS DOWN INTO THE UPPER 50S TO LOWER
60S.
AN UNSEASONABLY COLD AIRMASS WILL THEN INVADE THE GREAT LAKES REGION
FROM CANADA DURING THE UPCOMING WORK WEEK AS A DEEP TROUGH TAKES
CONTROL OF THE WEATHER. AS 850 MB TEMPERATURES TUMBLE WELL INTO THE
SINGLE DIGITS ABOVE ZERO...HIGH TEMPERATURES WILL BE LIMITED TO THE
MIDDLE TO UPPER 60S ON TUESDAY AS LOWS TUESDAY NIGHT FALL INTO THE
LOWER TO MIDDLE 50S TUESDAY NIGHT. THIS COLD AIR MASS COULD
CHALLENGE SOME RECORDS...ESPECIALLY WEDNESDAY WHEN THE RECORDS ARE
FAIRLY HIGH. WITHIN THE TROUGH PRECIPITATION CHANCES WILL
REMAIN...ALTHOUGH THE BEST CHANCES WILL BE DURING THE DAYTIME WHEN
DIURNAL HEATING PROVIDES A BOOST TO RAIN CHANCES. MODEST RIDGING
WILL PUSH DAYTIME HIGHS BACK INTO THE UPPER 70S BY FRIDAY...WHICH IS
STILL A GOOD 5 DEGREES BELOW NORMAL FOR THIS TIME OF YEAR.
MARINE...
LIGHT SOUTHERLY WINDS TODAY WILL BRING WARMER AND MORE HUMID
AIR INTO THE REGION BY LATE IN THE DAY. THE CHANCE FOR SHOWERS AND
THUNDERSTORMS WILL INCREASE OVER THE CENTRAL GREAT LAKES BY LATE
TODAY AND TONIGHT...CONTINUING INTO SUNDAY. AN UNSEASONABLY COOL
AIRMASS WILL TRACK INTO THE REGION DURING THE EARLY PART OF THE
WEEK...WITH GUSTY WEST WINDS EXPECTED ON TUESDAY. HOWEVER WINDS AND
WAVES ARE EXPECTED TO REMAIN BELOW HEADLINE CRITERIA.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....CB
UPDATE.......CB
SHORT TERM...DRK
LONG TERM....KURIMSKI
MARINE.......KURIMSKI
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1211 PM EDT SAT JUL 12 2014
LATEST UPDATE...
MARINE
.SYNOPSIS...
ISSUED AT 313 AM EDT SAT JUL 12 2014
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE TODAY...BUT THE BULK OF
THEM SHOULD HOLD UNTIL LATE THIS AFTERNOON. THE SHOWERS AND STORMS
WILL THEN CONTINUE INTO TONIGHT...BEFORE DIMINISHING SUNDAY
MORNING. PERIODS OF HEAVY RAIN WILL BE POSSIBLE TONIGHT INTO EARLY
SUNDAY MORNING MAINLY ALONG AND SOUTH OF I-96. THERE IS ALSO THE
SLIGHT RISK FOR SEVERE STORMS TONIGHT...MAINLY SOUTHWEST OF GRAND
RAPIDS. WE WILL GRADUALLY DRY OUT SUNDAY AFTERNOON AND SUNDAY
NIGHT. THEN MORE SHOWERS AND A FEW THUNDERSTORMS WILL BE POSSIBLE
AGAIN ON MONDAY...MAINLY NORTH OF I-96. DAYTIME TEMPERATURES WILL
BE AROUND 80 TODAY AND SUNDAY...THEN COOL TO 70 TO 75 BY MONDAY.
THE SHOWERS ARE EXPECTED TO MOVE OUT OF THE AREA MONDAY NIGHT WITH
COOLER AIR FILTERING IN. HIGHS ON TUESDAY AND WEDNESDAY SHOULD ONLY
BE AROUND 70...BUT THEN WARM TO AROUND 80 FOR THURSDAY AND FRIDAY.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 313 AM EDT SAT JUL 12 2014
A COLD FRONT WAS JUST MOVING ACROSS THE MS RIVER EARLY THIS
MORNING...ALONG THE MN/WI BORDER. MAIN MOISTURE FLUX AND LIFT WILL
STILL REMAIN TO OUR WEST MUCH OF THE DAY. THEREFORE WILL LOWER POPS
AS THE MAIN FORCING DOES NOT ARRIVE UNTIL LATE AFTERNOON AND INTO
THIS EVENING. WILL CARRY CHANCE POPS THROUGH MID AFTERNOON...THEN
RAMP THEM UP TO LIKELY AFTER 5 PM AS THE FRONT REACHES EASTERN
WISCONSIN BY THE END OF THE DAY.
TONIGHT CONTINUES TO LOOKS QUITE WET...ESPECIALLY ALONG AND SOUTH OF
I-96 WHERE DEEP MOISTURE POOLS AHEAD OF THE FRONT AND PERSISTS THERE
THROUGHOUT THE NIGHT. PRECIPITABLE WATER VALUES CONTINUE TO BE NEAR
OR SLIGHTLY OVER 2 INCHES. THOUGHT ABOUT ISSUING A FLOOD WATCH...
BUT NOT SURE HOW WIDESPREAD THE HEAVY RAIN WILL BE OR IF WE WILL
JUST SEE POCKETS OF HEAVY RAINS. CONFIDENCE WAS NOT STRONG ENOUGH
AT THIS POINT.
THE RISK OF SEVERE STORMS APPEARS A BIT LESSEN NOW THAT THE LOW
LEVEL JET SEEMS TO ARRIVE AFTER 06Z...DURING AN INSTABILITY DOWNWARD
TREND BY THAT HOUR. CAN NOT RULE OUT THAT A STRONGER STORM OR TWO
MAY MOVE ACROSS THE LAKE AND IMPACT AREAS ALONG AND SOUTH OF I-96.
THE FRONT AND THE BULK OF THE PCPN SHOULD MOVE OUT SUNDAY MORNING.
THERE IS A SECONDARY SURFACE TROUGH THAT PASSES THROUGH DURING THE
AFTERNOON AND MAY PRODUCE A FEW SHOWERS AND STORMS...PARTICULARLY SE
OF GRR. THEN BY MONDAY AN UPPER LOW DROPS OVER THE U.P. THE
SOUTHERN CWA MAY BE DRY SLOTTED MUCH OF THE DAY...BUT WILL CARRY CHC
POPS ACROSS THE NORTH. AFTER HIGHS AROUND 80 TODAY AND SUNDAY...
TEMPS WILL COOL TO 70 TO 75 MONDAY.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 313 AM EDT SAT JUL 12 2014
AN UNUSUALLY CHILLY PERIOD OF WEATHER FOR MID JULY... IN SOUTHWEST
LOWER MICHIGAN... IS LOOKING MORE AND MORE LIKE WITH EACH MODEL RUN
THROUGH MOST OF THIS FORECAST TIME FRAME. EXPECT AFTERNOON
INSTABILITY SHOWERS AND ISOLATED THUNDERSTORMS... MOSTLY INLAND OF
US-131 TUESDAY AND WEDNESDAY. A FEW ISOLATED SHOWERS REMAIN POSSIBLE
THURSDAY AFTERNOON TOO. THEN DRY WEATHER WITH A SLOW WARM UP WILL
COMMENCE.
THE ECMWF CONTINUES TO BE PREFERRED TO THE GFS SINCE THE CONTINUITY
OF THE ECMWF REMAINS SUPERIOR TO THE GFS. THIS IS ESPECIALLY TRUE
IN THE MID LEVELS LIKE 700...500 AND 300 MB... THROUGH THIS FORECAST
PERIOD. THE ECMWF IS SLOWER TO EJECT THE UPPER LOW OVER THE GREAT
LAKES COMPARED TO THE GFS AND ECMWF CONTINUES TO BE SIGNIFICANTLY
FARTHER SOUTH WITH CENTER OF THE UPPER LEVEL LOW AS WELL. IT SHOULD
BE POINTED OUT THE CANADIAN GEM IS SIMILAR TO THE ECMWF IN TERMS OF
THE DEVELOPMENT AND MOVEMENT OF THE DEEP 500 MB LOW OVER LOWER
MICHIGAN TUESDAY INTO WEDNESDAY.
WITH THE COLD POOL OF AIR ASSOCIATED WITH THE UPPER LOW REMAINING IN
PLACE TUESDAY INTO WEDNESDAY...AND LOOKING AT MODEL SOUNDING IT SURE
LOOKS TO ME LIKE THERE WOULD BE SCATTERED SHOWERS AND THUNDERSTORMS
AROUND THE AREA. TYPICAL OF THIS SORT OF SET UP IN THE SUMMER
TIME... SMALL HAIL IS CLASSIC CHARACTERISTIC OF THIS SORT OF
SCENARIO. ECMWF MODEL SOUNDING WOULD ALSO SUPPORT THIS (INTO
WEDNESDAY EVENING). BEYOND THAT THE UPPER LOW SLOWER MOVES EAST OF
THE AREA AND BY THURSDAY AFTERNOON THE BACK EDGE OF THE UPPER LEVEL
JET IS OVER LAKE MICHIGAN (ECMWF). SO I KEEP THE CHANCE OF SHOWERS
GOING INTO THURSDAY AFTERNOON SINCE WE WOULD STILL HAVE ENOUGH COLD
AIR ALOFT TO SPARK CONVECTION. I DID TREND THE POP DOWN EACH
AFTERNOON AS THAT IS ALSO TYPICAL OF THIS SORT OF EVENT. WATER
SPOUTS MAY BE POSSIBLE GIVEN HOW COLD THE AIR WILL BE AT MID LEVELS.
TEMPERATURES WILL RUN WELL BELOW NORMAL... AS MUCH AS 10 TO 15
DEGREES BELOW NORMAL FOR TUE AND WEDNESDAY. IT WOULD NOT BE OUT OF
THE QUESTION AREAS EAST OF REED CITY ALONG ROUTE 10 COULD SEE SOME
PATCHY FROST WED NIGHT AND THURSDAY NIGHT. BY FRIDAY TEMPERATURES
WILL HAVE WARMED TO WITHING 5 DEGREES OF NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 746 AM EDT SAT JUL 12 2014
CURRENTLY ALL TAF SITES ARE VFR AND SHOULD REMAIN SO THROUGH MID
AFTERNOON. CONDITIONS SHOULD DETERIORATE EARLY TONIGHT AND I WOULD
EXPECT LARGELY IFR/MVFR CONDITIONS AFTER 06Z AT ALL TAF SITES.
BASED ON BOTH THE HRRR IN COMBINATION WITH NAMDNG5 IT SEEMS THE
BULK OF THE THUNDERSTORMS ACTIVITY WILL BE IN THE 03Z TO 09Z TIME
FRAME. WHILE A FEW SCATTERED SHOWERS/THUNDERSTORMS (HRRR) COULD
IMPACT THE TAF SITES BY LATE AFTERNOON... THE UPPER DYNAMICS IN
COMBINATION WITH THE LOW LEVEL JET SUGGEST THE BULK OF THE STORM
ACTIVITY WILL BE AFTER 03Z SO ALL THE TAFS WERE WRITING TO SHOW
THE THUNDERSTORM ACTIVITY MOSTLY IN THAT TIME RANGE. SEEMS THESE
WILL BE TRAINING STORMS SO ONCE OVER THE TAF SITES THEY SHOULD NOT
BE QUICK TO LEAVE. IT IS AT THAT TIME THE CEILINGS/VSBY WILL
LIKELY GO MVFR/IFR. THE LOW CEILING/VSBY SHOULD CONTINUE THROUGH
12Z SUNDAY EVEN IF THE RAIN HAS ENDED BY THEN.
&&
.MARINE...
ISSUED AT 1206 PM EDT SAT JUL 12 2014
THE SOUTHERLY FLOW WILL KEEP THE WAVES GENERALLY IN THE 1 TO 3
FOOT RANGE WITH SOME VALUES UP NEAR 4 FEET BY THE TIME YOU GET TO
BIG SABLE POINT. OVERALL THE WINDS DO NOT STRENGTHEN...SO NO
HEADLINES AT THIS TIME. NEAR ANY THUNDERSTORMS...WINDS AND WAVES
COULD BE HIGHER.
&&
.HYDROLOGY...
ISSUED AT 249 PM EDT FRI JUL 11 2014
MAY NEED TO CONSIDER A FLOOD WATCH FOR SATURDAY AFTERNOON THROUGH
SUNDAY NIGHT. LOW LCLS...DEEP CAPE AND A DEEP WARM CLOUD LAYER
SUPPORT EFFICIENT RAINFALL PROCESS. LOCAL AMOUNTS WELL OVER 2 INCHES
POSSIBLE...ESPECIALLY IF THE STORMS TRAIN. CORFIDI DO BECOME SMALL
SAT NIGHT. THE OVERALL RISK WILL DEPEND ON HOW THE CONVECTION
UNFOLDS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...WDM
AVIATION...WDM
HYDROLOGY...MJS
MARINE...MJS
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
308 PM CDT SAT JUL 12 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 308 PM CDT SAT JUL 12 2014
RADAR IMAGERY CONTINUES TO SHOW RAIN WITH EMBEDDED THUNDERSTORMS
OVER THE AREA AS OF 330 PM. PCPN WAS FOCUSED OVER TWO AREAS... ONE
NEAR THE IOWA BORDER AND ANOTHER FROM EAST CENTRAL INTO WEST CENTRAL
MINNESOTA. THE FORMER AREA WAS BEING SUPPORTED BY A SHORTWAVE
EVIDENT IN WATER VAPOR IMAGERY OVER FAR SOUTHERN MINNESOTA AND THE
MAIN INSTABILITY GRADIENT/BAROCLINIC ZONE. HOWEVER... THE LATTER WAS
BEING AIDED BY THE SECONDARY FRONT/DEWPOINT GRADIENT DROPPING
SOUTHEAST THROUGH THE AREA AHEAD OF THE SHORTWAVE TROUGH PUSHING
EAST FROM THE DAKOTAS INTO MINNESOTA. MLCAPE VALUES OF 250-1000 J/KG
WERE APPARENT IN THE SPC MESOANALYSIS OVER THE EASTERN PORTION OF
THE AREA... WHERE EMBEDDED STORMS WITH HIGH RAINFALL RATES WERE
PRESENT. SOME PEA SIZED HAIL WAS OCCURRING WITH THE STRONGEST
STORMS... WHICH HAD SOME BETTER CORES ABV 25K FT AGL. THE HRRR HAS
HAD A DECENT HANDLE ON THINGS THROUGH THE DAY... SO GENERALLY
FOLLOWED ITS GUIDANCE TOGETHER WITH NEIGHBORHOOD PROBABILITIES FROM
THE HOPWRF. THAT BEING SAID... EXPECT THINGS TO SHIFT EAST/SOUTH
THROUGH EARLY EVENING... WITH MOST OF THE CWFA BECOMING PCPN FREE
BETWEEN 00Z AND 03Z. WE COULD SEE SOME SHRA SNEAK BACK INTO THE
NORTHWEST/NORTH CENTRAL PORTION OF THE AREA LATER THIS EVENING AND
OVERNIGHT BEHIND THE FRONTAL BOUNDARY AS THE MID-UPPER LEVEL PV LOBE
SWINGS THROUGH THAT AREA. COLD ADVECTION WILL ASSERT ITSELF OVER THE
AREA ON SUNDAY. SUBSIDENCE WITH THE COLD ADVECTION SHOULD BE
SUFFICIENT TO KEEP ANY SHRA FROM DEVELOPING ON SUNDAY GIVEN THAT THE
BETTER LOW-MID LEVEL LAPSE RATES WILL STILL BE UPSTREAM AND CLOSER
TO THE UPPER LOW AT THAT POINT. SO... EXPECT MAINLY JUST DIURNAL CU
WITH TEMPERATURES GETTING INTO THE LOWER TO MIDDLE 70S.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 308 PM CDT SAT JUL 12 2014
THE UPPER LOW WILL BEGIN DIGGING SOUTH AGGRESSIVELY SUNDAY NIGHT
AND WILL REACH THE CENTRAL GREAT LAKES MONDAY. CLOUDS AND
SCATTERED TO NUMEROUS SHOWERS WILL ACCOMPANY THE LOW
MONDAY...GREATEST COVERAGE NEAR THE LOW OVER WESTERN WI. STEEP LOW
LEVEL LAPSE RATES IN THE STRONG CAA REGIME MAY RESULT IN SOME
ISOLATED THUNDER...BUT NOTHING THAT WILL BE TOO STRONG GIVEN THE
RELATIVELY SHALLOW INSTABILITY/MOIST LAYER - MORE LIKE AN ISOLATED
STRIKE OR TWO AT BEST.
THE BIGGER STORY MONDAY WILL BE THE MUCH COOLER THAN NORMAL
TEMPERATURES EXPECTED. 925 MB TEMPS OF ONLY ABOUT +10C AND 850 MB
TEMPS AT BEST A FEW DEGREES ABOVE 0C WILL ALLOW HIGHS TO ONLY
REACH THE LOW TO MID 60S...EVEN IF THE SUN CAN MAKE A BRIEF
APPEARANCE. RECORD LOW MAX TEMPS ARE 68 AT MSP...STC AND EAU AND
RECORD LOWS MONDAY NIGHT ARE MID TO UPPER 40S. THE RECORD LOWS MAY
BE A BIT OF A STRETCH...BUT THE COLD HIGHS SHOULD BE RELATIVELY
EASILY ATTAINABLE IF HIGHS ARE NOT REACHED AT 06Z MONDAY.
THE TROUGH WILL SLOWLY LIFT OUT FOR MID TO LATE WEEK...BUT THE
MOISTURE WILL EXIT AS EARLY AS MONDAY NIGHT. THEREFORE...EXPECTING
A MOSTLY CLEAR REST OF THE WEEK WITH SLOWLY MODERATING TEMPERATURES.
FOR MOST...THIS MAY BE CONSIDERED THE NICEST WEEK OF THE SUMMER
THUS FAR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1248 PM CDT SAT JUL 12 2014
UPPER WAVE MOVING ACROSS SRN MN THIS MORNING IS ALSO HELPING TO
PUSH A COLD FRONT ACROSS THE AREA AS WELL...WITH AREAS OF SHOWERS
AND STORMS DEVELOPING OUT AHEAD OF IT. INSTABILITY IS SOMEWHAT
LIMITED...SO UPDRAFTS HAVE BEEN STRONG ENOUGH TO PRODUCE SOME
HEAVY DOWNPOURS...BUT NOT MUCH IN THE WAY OF LIGHTNING...SO TRENDED
PRECIP MENTION IN TAFS MORE TOWARD A SHRA MENTION. OUTSIDE OF
BEING A LITTLE SLOW IN DEVELOPING ACTIVITY...THE HRRR HAS HAD A
GOOD HANDEL ON ACTIVITY THIS MORNING...SO FOLLOWED IT TO TIME
ACTIVITY ACROSS THE TERMINALS. THERE IS ALSO AN AREA OF SHRA IN
THE WAKE OF THE FRONT ACROSS WRN MN...BUT WITH CIGS GETTING EVER
HIGHER OUT WEST...THAT RAIN WILL LIKELY HAVE A TOUGH TIME GETTING
MUCH FARTHER WEST OF ITS CURRENT LOCATION. AS THE FRONT MOVES
THROUGH IT WILL BE TAKING THE IFR/MVFR CIGS WITH IT...WITH VFR
CONDITIONS EXPECTED TO PREVAIL THE REST OF THE TAF. WILL HAVE TO
WATCH THE POTENTIAL FOR FOG TONIGHT AS SKIES CLEAR OUT...BUT WE
WILL BE BRINGING IN DRIER AIR THROUGH THE NIGHT AS WELL...SO THAT
SHOULD KEEP ANY LOWER VSBYS IN CHECK. WINDS WILL GRADUALLY TREND
MORE NWRLY OVERNIGHT...WITH SPEEDS INCREASING AND A FEW GUSTS OUT
OF THE NW DEVELOPING BY LATE SUNDAY MORNING.
KMSP...LIGHTNING ACTIVITY HAS BEEN MINIMAL WITH ACTIVITY THIS
MORNING AND WITH CLOUD TOPS RELATIVELY WARM...WILL LIKELY SEE
LIGHTNING ACTIVITY CONTINUE TO BE PRETTY SPARSE THROUGH THE
AFTERNOON...SO FEEL COMFORTABLE WITH JUST THE VCTS MENTION. THIS
ACTIVITY SHOULD CLEAR THE FIELD BY 23Z WITH NO OTHER ISSUES
EXPECTED THIS TAF PERIOD OTHER THAN THE NW WINDS STARTING TO GET
GUSTY BY SUNDAY AFTERNOON.
/OUTLOOK FOR KMSP/
MON...MVFR PSBL WITH CHC OF SHRA/TSRA. NW WINDS 15-30 KTS.
TUE...VFR. NW WINDS 10-15 KTS.
WED...VFR. NW WINDS 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...
LONG TERM...BORGHOFF
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
107 PM CDT SAT JUL 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 248 AM CDT SAT JUL 12 2014
IT`S WARM AND MUGGY ACROSS THE FORECAST AREA THIS MORNING...BUT SO
FAR THE HEAVY RAIN HAS REMAINED JUST TO THE SOUTH AND WEST
ACROSS SD/NE/IA. THIS SHOULD CHANGE OVER THE NEXT SEVERAL HOURS AS
MORE ACTIVITY IS EXPECTED TO FORM FARTHER NORTHEAST...ACROSS
SOUTHERN MINNESOTA. THE DEWPOINTS ARE EXPECTED TO SLOWLY FALL
TODAY...BUT THERE WON`T BE A DRAMATIC CHANGE IN THE AIRMASS
LOCALLY UNTIL NORTHWEST FLOW DEVELOPS ON SUNDAY.
WELL YOU REALLY WOULDN`T KNOW IT...BUT THERE IS A SLOW MOVING COLD
FRONT CREEPING SOUTHEAST ACROSS MINNESOTA EARLY THIS MORNING.
TEMPS AND DEWPOINTS ACROSS PORTIONS OF NORTHERN MN ARE 5-15
DEGREES COOLER THAN THEY WERE AT THIS TIME FRIDAY MORNING. THE
WIDESPREAD THUNDERSTORMS OFF TO OUR SOUTH AND WEST ARE CLOSER TO
THE SURFACE WARM FRONT IN AN AREA OF GOOD MID-LEVEL WARM ADVECTION
AND FGEN. THERE ARE ALSO PWATS NEAR 2" AND GOOD 850-300MB
THICKNESS DIFFLUENCE ACROSS IA...SO THERE IS A LOT WORKING IN
FAVOR FOR HEAVY RAIN IN AREAS TO OUR SOUTH. THAT BEING
SAID...SOUTHERN MN SHOULD SEE A SLIGHT INCREASE IN 925-850MB
MOISTURE TRANSPORT LATE THIS MORNING WITH MORE OF A SOUTHWEST
ORIENTATION TO THE LOW LEVEL FLOW VECTORS /THEY`VE BEEN NEAR ZERO
OR NORTH MOST OF THE NIGHT/. THERE IS ALSO A WEAK SHORTWAVE AND PV
FEATURE LOCATED IN ND/SD EARLY THIS MORNING...WHICH IS RESPONSIBLE
FOR THE CONVECTION FROM PIERRE, SD BACK TOWARD THE BLACK HILLS.
THIS FEATURE SHOULD MAKE IT TO THE SD/MN BORDER BY AROUND
15Z...WHICH COULD THEN KICK OFF MORE THUNDERSTORMS LATE THIS
MORNING AND INTO THE AFTERNOON. IN THE MEANTIME...WE ARE ALREADY
SEEING ACTIVITY IN SD TRANSLATE FARTHER EAST AND APPROACH THE
STATE LINE...NOT TO MENTION A COUPLE SHOWERS AND ENHANCED CUMULUS
DEVELOPMENT GOING UP ALONG THE SLOW MOVING COLD FRONT IN
MINNESOTA. THE SIGNAL FOR WIDESPREAD HEAVY RAIN OR EVEN WIDESPREAD
RAIN ISN`T GREAT TODAY...BUT THERE IS STILL PLENTY OF MOISTURE
AROUND AND ENOUGH FORCING TO JUSTIFY 40-70% RAIN ACROSS THE
FORECAST AREA. WE ARE SIMPLY NOT EXACTLY SURE WHICH FORCING
MECHANISM WILL DOMINATE AND AT WHAT TIME. THE AVAILABLE CAM
GUIDANCE OVERNIGHT...DOES SUGGEST A COUPLE DISTINCT AREAS OF
CONVECTIVE INITIATION ACROSS THE FORECAST TODAY /ONE NORTH AND ONE
SOUTH/...BUT THERE IS CONSIDERABLE DIFFERENCES IN TIMING AND
PLACEMENT...SO IT IS DIFFICULT TO INCLUDE HIGHER THAN 70-75%
CHANCE OF RAIN AT ANY ONE LOCATION GIVEN THE UNCERTAINTY. THUNDER
DOES SEEM MUCH MORE LIKELY ACROSS SOUTHERN MN WHEN COMPARED TO
WHAT IS EXPECTED IN CENTRAL MN AND EVEN WEST CENTRAL MN.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 248 AM CDT SAT JUL 12 2014
THE PERIOD WILL BEGIN WITH A CDFNT HAVING JUST SANK TO THE S OF
THE MPX CWFA...AND THIS WILL BEGIN THE POTENT CAA ADVERTISED FOR
THE N-CENTRAL CONUS OVER THE PAST SEVERAL DAYS. WHILE THE CDFNT
DROPS FURTHER S AND E DURG THE DAY SUN AND SUN NIGHT...A DEEP UPR
LVL CUTOFF LOW WILL DROP S FROM CENTRAL CANADA INTO THE GRT LKS
SUN NIGHT INTO MON. THERE WILL BE ENOUGH SEPARATION BETWEEN BOTH
FEATURES SUCH THAT A DRY DAY ON SUN FOR THE ENTIRE CWFA LOOKS IN
ORDER. HOWEVER...AS THE UPR LOW NEARS...SEVERAL SHTWV TROUGH AXES
WILL ROTATE ARND THE WRN FRINGES OF THE UPR LOW. IN ADDITION...A
WEAK POST-FRONTAL SFC TROUGH WILL ALSO DROP THRU THE REGION ON
MON...ALLOWING FOR SCATTERED RAIN SHWRS TO DEVELOP ACRS THE AREA.
AS THE UPR LOW PULLS AWAY FROM THE AREA MON NIGHT INTO TUE...THE
POTENTIAL FOR PRECIP WILL ALSO SHIFT OFF TO THE E. THUS LEAVING
THE MAIN STORY TO BE THE DROP IN TEMPERATURES. H85 TEMPS STILL
LOOK TO DROP TO THE 4 TO 6 DEG C RANGE...WELL BELOW NORMAL FOR
MID-JULY...AND THIS WILL TRANSLATE TO SFC TEMPS ARND 15 DEGREES
BELOW NORMAL. THE COLDEST AIR WILL DROP THRU THE REGION SUN NIGHT
THRU TUE NIGHT...WHERE HIGHS WILL ONLY HIT THE 60S WITH LOWS AS
FAR DOWN AS THE LWR 50S AND POTENTIALLY SOME UPR 40S IN NORMALLY
COLDER LOCATIONS. TEMPS DO LOOK TO MODERATE GOING INTO THE MID-TO-
LATE WEEK PERIOD AND THIS WILL BE ACCOMPANIED BY EXTENSIVE HIGH
PRES THAT WILL KEEP PRECIP AWAY FROM THE REGION STARTING TUE
NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1248 PM CDT SAT JUL 12 2014
UPPER WAVE MOVING ACROSS SRN MN THIS MORNING IS ALSO HELPING TO
PUSH A COLD FRONT ACROSS THE AREA AS WELL...WITH AREAS OF SHOWERS
AND STORMS DEVELOPING OUT AHEAD OF IT. INSTABILITY IS SOMEWHAT
LIMITED...SO UPDRAFTS HAVE BEEN STRONG ENOUGH TO PRODUCE SOME
HEAVY DOWNPOURS...BUT NOT MUCH IN THE WAY OF LIGHTNING...SO TRENDED
PRECIP MENTION IN TAFS MORE TOWARD A SHRA MENTION. OUTSIDE OF
BEING A LITTLE SLOW IN DEVELOPING ACTIVITY...THE HRRR HAS HAD A
GOOD HANDEL ON ACTIVITY THIS MORNING...SO FOLLOWED IT TO TIME
ACTIVITY ACROSS THE TERMINALS. THERE IS ALSO AN AREA OF SHRA IN
THE WAKE OF THE FRONT ACROSS WRN MN...BUT WITH CIGS GETTING EVER
HIGHER OUT WEST...THAT RAIN WILL LIKELY HAVE A TOUGH TIME GETTING
MUCH FARTHER WEST OF ITS CURRENT LOCATION. AS THE FRONT MOVES
THROUGH IT WILL BE TAKING THE IFR/MVFR CIGS WITH IT...WITH VFR
CONDITIONS EXPECTED TO PREVAIL THE REST OF THE TAF. WILL HAVE TO
WATCH THE POTENTIAL FOR FOG TONIGHT AS SKIES CLEAR OUT...BUT WE
WILL BE BRINGING IN DRIER AIR THROUGH THE NIGHT AS WELL...SO THAT
SHOULD KEEP ANY LOWER VSBYS IN CHECK. WINDS WILL GRADUALLY TREND
MORE NWRLY OVERNIGHT...WITH SPEEDS INCREASING AND A FEW GUSTS OUT
OF THE NW DEVELOPING BY LATE SUNDAY MORNING.
KMSP...LIGHTNING ACTIVITY HAS BEEN MINIMAL WITH ACTIVITY THIS
MORNING AND WITH CLOUD TOPS RELATIVELY WARM...WILL LIKELY SEE
LIGHTNING ACTIVITY CONTINUE TO BE PRETTY SPARSE THROUGH THE
AFTERNOON...SO FEEL COMFORTABLE WITH JUST THE VCTS MENTION. THIS
ACTIVITY SHOULD CLEAR THE FIELD BY 23Z WITH NO OTHER ISSUES
EXPECTED THIS TAF PERIOD OTHER THAN THE NW WINDS STARTING TO GET
GUSTY BY SUNDAY AFTERNOON.
/OUTLOOK FOR KMSP/
MON...MVFR PSBL WITH CHC OF SHRA/TSRA. NW WINDS 15-30 KTS.
TUE...VFR. NW WINDS 10-15 KTS.
WED...VFR. NW WINDS 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...CLF
LONG TERM...JPC
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1229 PM CDT Sat Jul 12 2014
.DISCUSSION...
Issued at 351 AM CDT SAT JUL 12 2014
Overnight convection remains mostly located in areas from northeast
Nebraska arching through central Iowa into Illinois, which coincides
with edge of the nocturnal jet where warm air and moisture transport
is piling up early this morning. Closer to home, starting to get
some scattered radar returns across central Missouri likely owing to
weak moisture transport noted from the SPCs meso-analysis page.
Early morning showers in central Missouri don`t look like they will
last long. HRRR and other meso-models advertising this modest
activity all have it dissipating as quickly as it appeared as the
primary focus for moisture transport will remain to our north along
the southern edge of the prevailing westerlies across Nebraska and
Iowa today. Convection to our north will likely reinforce a weak
cold front settling south into Kansas and Missouri late tonight,
which will eventually bring the focus for some rain farther south
--likely after midnight--. However, before that occurs we will have
to get through a hot and muggy day. H8 temperatures today in the 20C
to 22C range, along with plenty of insolation thanks to clearing
skies, should allow temperates to reach into the 90s across the
entire forecast region today.
For tonight...have bumped POPs after midnight into the likely range
as models are consistent in settling the activity across Nebraska
and Iowa into at least northern Missouri as the front settles south.
Rainfall totals across far northern Missouri could be a bit high
owing to precipitable water values will be over 1.5 inches, though
the storms should be progressive enough with the fronts movement to
limit flooding issues. Otherwise, severe potential can not be ruled
out, but shear looks highly confined to the front and late night
instability is not looking overly favorable. That said, small hail,
locally gusty winds and torrential rain would be the hazards to
highlight with any of our late Saturday Night/early Sunday Morning
activity.
Storm chances will linger into Sunday, but the next best chance for
storms looks to hold off till Monday as a shortwave trough rotates
through the northern Plains into the Great Lakes. This will push a
more substantial cold front into Missouri providing focus for more
storms.
Otherwise, still looking at the potential for record low maximum
temperatures for Tuesday and record low temperatures both Tuesday
and Wednesday as cool Canadian air settles south into the Plains
States.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1225 PM CDT SAT JUL 12 2014
Forecast still on track for areas of thunderstorm activity north of
the terminals through the evening hours. As the boundary sags
southward winds will eventually go light and variable. Concurrent
with the surface boundary could be periods of thunderstorm activity,
most likely during the late evening to overnight period. Confidence
in TS actually affecting the terminal is higher at KSTJ, with
confidence in TS at the terminal dropping quite a bit at KMCI and
KMKC. Will continue to carry VCTS group for now, and if convection
looks like it will make it into the terminals address it with future
forecast or AMD. Another concern for a brief 2-3 hour period of MVFR
CIGs also exists post frontal, but the saturated layer appears to be
shallow and short-lived, so left it out of this forecast.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
DISCUSSION...Cutter
AVIATION...Leighton
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1238 PM CDT SAT JUL 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM CDT SAT JUL 12 2014
THE MODELS BRING ANOTHER DISTURBANCE THROUGH THE FCST AREA THIS
AFTERNOON. THERE ARE DIFFERENCES IN THE FOCUS FOR THUNDERSTORM
DEVELOPMENT. THE ECM FAVORS THE HIGH PLAINS AND SWRN NEB WHILE
THE NAM AND GEM SOLNS FAVOR NRN NEB. THE FORECAST FOLLOWS A BLEND
OF THESE SOLNS FOR ISOLATED TO SCATTERED POPS. NONE OF THE MODELS
SHOW HEAVY RAIN DEVELOPING BUT GIVEN THE WEAK FOCUS THIS MIGHT BE
NORMAL.
THE RAP SUGGESTS NO SIGNIFICANT DECREASE IN MOISTURE...PWS OVER
1.5 INCHES...SO STORMS WHICH FORM SHOULD CONTINUE TO PRODUCE
LOCALLY HEAVY RAINFALL.
LIGHT NORTH WINDS DEVELOP TODAY WITH LOW PRESSURE SOUTH OF THE
FCST AREA. THIS SHOULD LIMIT HIGHS TO THE 70S TO MID 80S. TONIGHT
LOWS FALL INTO THE 50S TO LOWER 60S AS THE FIRST PUSH OF DRIER
COOLER AIR MOVES INTO THE FCST AREA.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 354 AM CDT SAT JUL 12 2014
A COLD FRONT WILL PUSH INTO THE REGION LATE SUNDAY. AHEAD OF THE
FRONT PARTLY CLOUDY TO MOSTLY SUNNY SKIES SHOULD HELP TO WARM
TEMPS INTO THE 80S. ELEVATED INSTABILITY IS MARGINAL AND NOT
LOOKING AS GOOD AS YESTERDAY. PWATS DROP TO AROUND 1 INCH...WHICH
IS BELOW THE 50 PERCENTILE FOR JULY. EVEN THOUGH MOISTURE IS
LIMITED COOL AIR ALOFT WILL CREATE SOME STEEP LAPSE RATES. LOWERED
POPS FOR THE DAY...ALTHOUGH DID NOT ELIMINATE. MEANWHILE
UNSEASONABLY COLD UPPER LEVEL WILL BE DRIFTING ACROSS CENTRAL
CANADA TOWARDS THE GREAT LAKES.
THE COLD FRONT WILL MOVE ACROSS THE AREA SUNDAY NIGHT. SFC HIGH
PRESSURE WILL DEVELOP OVER THE DAKOTAS INTO NEB FOR MONDAY. BY
TUESDAY NIGHT INTO WEDNESDAY THE HIGH WILL DOMINATE MOST OF THE
PLAINS. TEMPS ASSOCIATED WITH THE HIGH WILL BE NOTICEABLY
COOLER...WITH HIGHS ONLY IN THE 70S...WITH MANY LOCATIONS HOLDING
IN THE LOWER 70S. MONSOON FLOW CONTINUES ALONG THE
SOUTHERN/CENTRAL ROCKIES. MODELS BRING SOME OF THIS MOISTURE INTO
SW NEB AND WILL CONTINUE LOW POPS.
COLD SNAP WILL BEGIN TO RELAX LATE WED AS THE UPPER LEVEL LOW WILL
LIFT INTO TO THE NORTHEAST. THE WESTERN RIDGE WILL THEN EXPAND
ACROSS THE ROCKIES. MODELS PUSH THE MONSOON MOISTURE SOUTH AS WARM
AIR EXPANDS ACROSS THE AREA. HIGHS SHOULD REBOUND BACK TO AROUND
80 FOR THURSDAY AND INTO THE 80S FOR FRIDAY. NUMERICAL MOS
GUIDANCE BRINGS TEMPS INTO THE 90S FOR FRIDAY ACROSS THE
WEST...HOWEVER THE WAY THIS SUMMER HAS GONE...HIGHS LIKELY IN THE
MID TO UPPER 80S. FLOW BECOMES NORTHWEST AND WILL HAVE TO MONITOR
DISTURBANCES FOR POSSIBLE ISOLATED ACTIVITY. FORECAST IS DRY AT
THIS TIME...BUT LOW POPS MAY BE NEEDED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1237 PM CDT SAT JUL 12 2014
MODEL GUIDANCE HAS HAD DIFFICULTIES THUS FAR WITH THE STRATUS
THIS MORNING...STRUGGLING WITH THE EXTENT...TIMING OF BURN OFF AND
LOCATION...THUS FORECAST CONFIDENCE IS LOWER THAN USUAL IN THE NEAR
TERM. WITH THAT BEING SAID...THERE SHOULD BE GENERAL CEILING IMPROVEMENT
WITH MOST TERMINALS EXPERIENCING VFR BY 21Z TODAY. HOWEVER STORMS
MAY RE-FORM LATER THIS AFTERNOON/EVENING...WHICH COULD PRODUCE
HEAVY RAIN...ERRATIC WIND AND HAIL. ATTM...THE GREATEST THREAT OF
STORMS WILL BE ACROSS THE WESTERN SANDHILLS AND SOUTHWEST
NEBRASKA...BUT STORMS IMPACTING EASTERN TERMINALS CANNOT BE RULED
OUT. CONFIDENCE IN STORMS IMPACTING KLBF OR KVTN IS LOW ENOUGH TO
NOT INCLUDE A MENTION IN THE FORECAST AT THIS TIME. AVIATION
FORECAST AMENDMENTS MAY BE NEEDED IF CONVECTION IS REALIZED.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...JACOBS
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
135 PM EDT SAT JUL 12 2014
.SYNOPSIS...
HIGH PRESSURE OVER THE EASTERN SEABOARD WILL BRING ANOTHER NICE
DAY TO CENTRAL NEW YORK AND NORTHEAST PENNSYLVANIA. A STORM
SYSTEM WILL APPROACH THE REGION FROM THE WEST LATE TONIGHT BRINGING
A CHANCE FOR SHOWERS AND THUNDERSTORMS. THE CHANCE FOR SHOWERS
AND THUNDERSTORMS WILL CONTINUE INTO TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
1220 PM UPDATE...LOCAL RADAR SHOWING ISOLATED PULSE CONVECTION
OVER NE PA AND SRN CATSKILLS. WILL INCLUDE SLIGHT CHC ACROSS FA
THIS AFTERNOON EVEN THOUGH ALMOST ALL AREAS WILL REMAIN DRY.
1030 AM UPDATE...12Z BUF RAOB AND LATEST RAP SOUNDINGS SHOW A
FAIRLY STRONG CAP AROUND 700 MB WHICH WILL INHIBIT CONVECTION THIS
AFTERNOON. WILL CONTINUE WITH DRY FORECAST FOR THIS AFTERNOON JUST
MINOR TWEAKS TO TEMPS OTHERWISE ALL GOOD.
PREVIOUS DISC...
HIGH PRESSURE SLIDING OFF THE EAST COAST WILL ALLOW
WARMER AND MORE HUMID AIR TO WORK INTO THE REGION TODAY. MDL
PROFILES DISPLAY ALOT OF VARIABILITY THIS AFTN W/RESPECT TO POTNL
FOR AFTN CONVECTION. 00Z BUF PROFILE SHOWS A GOOD CAP AT 700 MB
WHICH WOULD TEND TO INHIBIT ACTIVITY. LOW LVL MSTR APPEARS
OVERDONE IN THE NAM...WHILE THE RUC MAY BE DISPLAYING A DRY BIAS
W/RESPECT TO LOW LVL TD/S. GFS PROFILES APPEAR TO BE MOST
REASONABLE AND SUGGEST THE CAP WILL BE ENUF TO SUPPRESS CONVECTION
THIS AFTN. IN ADDN...FCST K`S ARE GNRLY IN THE U20S THIS AFTN.
WHILE A STRAY SHRA CAN`T BE RULED OUT LATE TDA...WE`VE OPTED TO
LOWER POPS TO BLO SLGT CHC. BETTER CHCS FOR CONVECTION WILL COME
TWDS DAYBREAK AS LEADING S/WV AHEAD OF THE DEEPENING GTLAKES UPR
LOW APRCHS THE RGN.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
XPCT SHRA/TSRA TO OVERSPREAD THE RGN SUN MRNG...THEN WORK THRU
DURING THE DAY. CAPES GNRLY IN THE 500-1000 RNG...WITH RATHER
IMPRSV WIND FIELDS. THIS WOULD SUGGEST A LOW END SVR THREAT FOR
MUCH OF THE RGN. AFTER THIS 1ST WAVE WORKS THRU...SOME DIFFS DVLP
IN THE GUIDANCE W/RESPECT TO TIMING AND DVLPMT AHEAD OF THE MAIN
UPR TROF AXIS. XPCT ANOTHER PUSH OF MSTR NWD AS NXT WAVE APRCHS. WE
KEPT HIGH CHC/LIKELY POPS FOR THESE PDS. THE FINGER LAKES...WRN
MOHAWK VLY AND SRN TUG COULD SEE A MAINLY DRY DAY ON MON BEFORE
THE NXT WAVES MOVS IN...SO ONLY INDICATE CHC POPS THERE WITH
HIGHER POPS FURTHER TO THE SOUTH.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
NOON UPDATE...
AT THE BEGINNING OF THE LONG TERM FORECAST A COLD FRONT WILL BE
MOVING THROUGH THE AREA WITH SHOWERS ENDING EARLY TUESDAY NIGHT.
BEYOND THAT THE PERIOD WILL BE DOMINATED BY A CUT OFF LOW OVER
THE NORTHERN GREAT LAKES/SOUTHERN ONTARIO, THAT WILL KEEP OUR
WEATHER COOL. HIGHS DURING THE PERIOD WILL MOSTLY BE IN THE 70S,
WITH NIGHTTIME LOWS IN THE 50S (WITH 40S POSSIBLE IN OUR NORMALLY
COLDER SPOTS). BEYOND TUESDAY NIGHT, RAIN CHANCES LOOK LOW. WE
HAVE A SLIGHT CHANCE FOR A SHOWER WEDNESDAY NIGHT INTO EARLY
THURSDAY AS THE MAIN TROF AXIS MOVES THROUGH, AND YET AGAIN FRIDAY
NIGHT/EARLY SATURDAY AS SOME MOISTURE MOVES UP THE COAST. BOTH
CHANCES ARE TOO LOW RIGHT NOW TO INCLUDE ANY MENTION IN THE
FORECAST.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
MAINLY VFR WEATHER EXPECTED THROUGH EARLY SUNDAY MORNING. A SCT TO
AT TIMES BKN DECK OF CLOUDS AROUND 5KFT THIS AFTERNOON WILL GIVE
WAY TO JUST A FEW HIGH CLOUDS TONIGHT. A FEW ISOLATED SHOWERS ARE
POSSIBLE THIS AFTERNOON BUT WILL MAINLY BE EAST OF THE TERMINALS.
THE EXCEPTION WILL BE AT KAVP WHERE SHOWERS WILL BE AROUND BUT TOO
LIMITED IN DURATION OR COVERAGE TO INCLUDE ANY RESTRICTIONS.
FOG DOES NOT APPEAR LIKELY TONIGHT AT KELM DUE TO STRONG WINDS OFF
THE SURFACE. ON SUNDAY AHEAD OF A TROF A LINE OF SHOWERS AND
THUNDERSTORMS IS POSSIBLE BETWEEN 14Z AND 18Z. INCLUDED A PROB30
GROUP FOR THUNDER IN OUR MOST LIKELY AREAS FOR STORMS, WHICH WILL
BE ACROSS CENTRAL NY THROUGH EARLY AFTERNOON.
OUTLOOK...
SUN NIGHT THROUGH TUE NGT...POTENTIAL RESTRICTIONS FROM SHRA/TSRA.
WED/THUR...PRIMARILY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...RRM
SHORT TERM...
LONG TERM...HEDEN
AVIATION...HEDEN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1223 PM EDT SAT JUL 12 2014
.SYNOPSIS...
HIGH PRESSURE OVER THE EASTERN SEABOARD WILL BRING ANOTHER NICE
DAY TO CENTRAL NEW YORK AND NORTHEAST PENNSYLVANIA. A STORM
SYSTEM WILL APPROACH THE REGION FROM THE WEST LATE TONIGHT BRINGING
A CHANCE FOR SHOWERS AND THUNDERSTORMS. THE CHANCE FOR SHOWERS
AND THUNDERSTORMS WILL CONTINUE INTO TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
1220 PM UPDATE...LOCAL RADAR SHOWING ISOLATED PULSE CONVECTION
OVER NE PA AND SRN CATSKILLS. WILL INCLUDE SLIGHT CHC ACROSS FA
THIS AFTERNOON EVEN THOUGH ALMOST ALL AREAS WILL REMAIN DRY.
1030 AM UPDATE...12Z BUF RAOB AND LATEST RAP SOUNDINGS SHOW A
FAIRLY STRONG CAP AROUND 700 MB WHICH WILL INHIBIT CONVECTION THIS
AFTERNOON. WILL CONTINUE WITH DRY FORECAST FOR THIS AFTERNOON JUST
MINOR TWEAKS TO TEMPS OTHERWISE ALL GOOD.
PREVIOUS DISC...
HIGH PRESSURE SLIDING OFF THE EAST COAST WILL ALLOW
WARMER AND MORE HUMID AIR TO WORK INTO THE REGION TODAY. MDL
PROFILES DISPLAY ALOT OF VARIABILITY THIS AFTN W/RESPECT TO POTNL
FOR AFTN CONVECTION. 00Z BUF PROFILE SHOWS A GOOD CAP AT 700 MB
WHICH WOULD TEND TO INHIBIT ACTIVITY. LOW LVL MSTR APPEARS
OVERDONE IN THE NAM...WHILE THE RUC MAY BE DISPLAYING A DRY BIAS
W/RESPECT TO LOW LVL TD/S. GFS PROFILES APPEAR TO BE MOST
REASONABLE AND SUGGEST THE CAP WILL BE ENUF TO SUPPRESS CONVECTION
THIS AFTN. IN ADDN...FCST K`S ARE GNRLY IN THE U20S THIS AFTN.
WHILE A STRAY SHRA CAN`T BE RULED OUT LATE TDA...WE`VE OPTED TO
LOWER POPS TO BLO SLGT CHC. BETTER CHCS FOR CONVECTION WILL COME
TWDS DAYBREAK AS LEADING S/WV AHEAD OF THE DEEPENING GTLAKES UPR
LOW APRCHS THE RGN.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
XPCT SHRA/TSRA TO OVERSPREAD THE RGN SUN MRNG...THEN WORK THRU
DURING THE DAY. CAPES GNRLY IN THE 500-1000 RNG...WITH RATHER
IMPRSV WIND FIELDS. THIS WOULD SUGGEST A LOW END SVR THREAT FOR
MUCH OF THE RGN. AFTER THIS 1ST WAVE WORKS THRU...SOME DIFFS DVLP
IN THE GUIDANCE W/RESPECT TO TIMING AND DVLPMT AHEAD OF THE MAIN
UPR TROF AXIS. XPCT ANOTHER PUSH OF MSTR NWD AS NXT WAVE APRCHS. WE
KEPT HIGH CHC/LIKELY POPS FOR THESE PDS. THE FINGER LAKES...WRN
MOHAWK VLY AND SRN TUG COULD SEE A MAINLY DRY DAY ON MON BEFORE
THE NXT WAVES MOVS IN...SO ONLY INDICATE CHC POPS THERE WITH
HIGHER POPS FURTHER TO THE SOUTH.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
NOON UPDATE...
AT THE BEGINNING OF THE LONG TERM FORECAST A COLD FRONT WILL BE
MOVING THROUGH THE AREA WITH SHOWERS ENDING EARLY TUESDAY NIGHT.
BEYOND THAT THE PERIOD WILL BE DOMINATED BY A CUT OFF LOW OVER
THE NORTHERN GREAT LAKES/SOUTHERN ONTARIO, THAT WILL KEEP OUR
WEATHER COOL. HIGHS DURING THE PERIOD WILL MOSTLY BE IN THE 70S,
WITH NIGHTTIME LOWS IN THE 50S (WITH 40S POSSIBLE IN OUR NORMALLY
COLDER SPOTS). BEYOND TUESDAY NIGHT, RAIN CHANCES LOOK LOW. WE
HAVE A SLIGHT CHANCE FOR A SHOWER WEDNESDAY NIGHT INTO EARLY
THURSDAY AS THE MAIN TROF AXIS MOVES THROUGH, AND YET AGAIN FRIDAY
NIGHT/EARLY SATURDAY AS SOME MOISTURE MOVES UP THE COAST. BOTH
CHANCES ARE TOO LOW RIGHT NOW TO INCLUDE ANY MENTION IN THE
FORECAST.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
12Z UPDATE...
KELM HAS DROPPED DOWN TO MVFR VSBYS AND SHOULD REMAIN THERE
THROUGH 13Z, OTHER THAN THAT ALL TERMINALS SHOULD BE VFR FOR THE
NEXT 24 HOURS WITH THE POSSIBLE EXCEPTION OF AVP LATE IN THE
PERIOD. EXPECT ALL TERMINALS TO START OFF WITH A SCT MID-DECK ARND
7KFT AT 12Z WITH CUMULUS DEVELOPING BY 15Z WITH CLD HGTS STILL
REMAINING VFR AROUND 5KFT. CUMULUS EXPECTED TO DIMINISH BY 00Z
WITH JUST HIGH-LEVEL CIRRUS AHEAD OF NEXT WAVE LOWERING TO 10KFT
AT NY TERMINALS AFTER 09Z. AVP WILL BE LAST TO SEE BKN MID-DECK
ARRIVE IN, THUS HAVE GONE PREDOMINANT MVFR VSBYS AFTER 09Z AT THIS
TERMINAL. CONTINUE TO HAVE VERY LITTLE CONFIDENCE IN SHOWER
CHANCES TODAY AND WILL WITHHOLD FROM ANY TEMPO GROUPS UNTIL THEY
ACTUALLY DEVELOP.
WINDS LGT/VRB THIS MORNING WILL INCREASE TO BETWEEN 5-8 KTS OUT OF THE
SOUTHWEST BY MID-MORNING, DIMINISHING LATE IN THE DAY.
OUTLOOK...
SUN THROUGH TUE NGT...POTENTIAL RESTRICTIONS FROM SHRA/TSRA.
WED...PRIMARILY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...RRM
SHORT TERM...
LONG TERM...HEDEN
AVIATION...PVN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1217 PM EDT SAT JUL 12 2014
.SYNOPSIS...
HIGH PRESSURE OVER THE EASTERN SEABOARD WILL BRING ANOTHER NICE
DAY TO CENTRAL NEW YORK AND NORTHEAST PENNSYLVANIA. A STORM
SYSTEM WILL APPROACH THE REGION FROM THE WEST LATE TONIGHT BRINGING
A CHANCE FOR SHOWERS AND THUNDERSTORMS. THE CHANCE FOR SHOWERS
AND THUNDERSTORMS WILL CONTINUE INTO TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
1030 AM UPDATE...12Z BUF RAOB AND LATEST RAP SOUNDINGS SHOW A
FAIRLY STRONG CAP AROUND 700 MB WHICH WILL INHIBIT CONVECTION THIS
AFTERNOON. WILL CONTINUE WITH DRY FORECAST FOR THIS AFTERNOON JUST
MINOR TWEAKS TO TEMPS OTHERWISE ALL GOOD.
PREVIOUS DISC...
HIGH PRESSURE SLIDING OFF THE EAST COAST WILL ALLOW
WARMER AND MORE HUMID AIR TO WORK INTO THE REGION TODAY. MDL
PROFILES DISPLAY ALOT OF VARIABILITY THIS AFTN W/RESPECT TO POTNL
FOR AFTN CONVECTION. 00Z BUF PROFILE SHOWS A GOOD CAP AT 700 MB
WHICH WOULD TEND TO INHIBIT ACTIVITY. LOW LVL MSTR APPEARS
OVERDONE IN THE NAM...WHILE THE RUC MAY BE DISPLAYING A DRY BIAS
W/RESPECT TO LOW LVL TD/S. GFS PROFILES APPEAR TO BE MOST
REASONABLE AND SUGGEST THE CAP WILL BE ENUF TO SUPPRESS CONVECTION
THIS AFTN. IN ADDN...FCST K`S ARE GNRLY IN THE U20S THIS AFTN.
WHILE A STRAY SHRA CAN`T BE RULED OUT LATE TDA...WE`VE OPTED TO
LOWER POPS TO BLO SLGT CHC. BETTER CHCS FOR CONVECTION WILL COME
TWDS DAYBREAK AS LEADING S/WV AHEAD OF THE DEEPENING GTLAKES UPR
LOW APRCHS THE RGN.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
XPCT SHRA/TSRA TO OVERSPREAD THE RGN SUN MRNG...THEN WORK THRU
DURING THE DAY. CAPES GNRLY IN THE 500-1000 RNG...WITH RATHER
IMPRSV WIND FIELDS. THIS WOULD SUGGEST A LOW END SVR THREAT FOR
MUCH OF THE RGN. AFTER THIS 1ST WAVE WORKS THRU...SOME DIFFS DVLP
IN THE GUIDANCE W/RESPECT TO TIMING AND DVLPMT AHEAD OF THE MAIN
UPR TROF AXIS. XPCT ANOTHER PUSH OF MSTR NWD AS NXT WAVE APRCHS. WE
KEPT HIGH CHC/LIKELY POPS FOR THESE PDS. THE FINGER LAKES...WRN
MOHAWK VLY AND SRN TUG COULD SEE A MAINLY DRY DAY ON MON BEFORE
THE NXT WAVES MOVS IN...SO ONLY INDICATE CHC POPS THERE WITH
HIGHER POPS FURTHER TO THE SOUTH.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
NOON UPDATE...
AT THE BEGINNING OF THE LONG TERM FORECAST A COLD FRONT WILL BE
MOVING THROUGH THE AREA WITH SHOWERS ENDING EARLY TUESDAY NIGHT.
BEYOND THAT THE PERIOD WILL BE DOMINATED BY A CUT OFF LOW OVER
THE NORTHERN GREAT LAKES/SOUTHERN ONTARIO, THAT WILL KEEP OUR
WEATHER COOL. HIGHS DURING THE PERIOD WILL MOSTLY BE IN THE 70S,
WITH NIGHTTIME LOWS IN THE 50S (WITH 40S POSSIBLE IN OUR NORMALLY
COLDER SPOTS). BEYOND TUESDAY NIGHT, RAIN CHANCES LOOK LOW. WE
HAVE A SLIGHT CHANCE FOR A SHOWER WEDNESDAY NIGHT INTO EARLY
THURSDAY AS THE MAIN TROF AXIS MOVES THROUGH, AND YET AGAIN FRIDAY
NIGHT/EARLY SATURDAY AS SOME MOISTURE MOVES UP THE COAST. BOTH
CHANCES ARE TOO LOW RIGHT NOW TO INCLUDE ANY MENTION IN THE
FORECAST.
&&
.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
12Z UPDATE...
KELM HAS DROPPED DOWN TO MVFR VSBYS AND SHOULD REMAIN THERE
THROUGH 13Z, OTHER THAN THAT ALL TERMINALS SHOULD BE VFR FOR THE
NEXT 24 HOURS WITH THE POSSIBLE EXCEPTION OF AVP LATE IN THE
PERIOD. EXPECT ALL TERMINALS TO START OFF WITH A SCT MID-DECK ARND
7KFT AT 12Z WITH CUMULUS DEVELOPING BY 15Z WITH CLD HGTS STILL
REMAINING VFR AROUND 5KFT. CUMULUS EXPECTED TO DIMINISH BY 00Z
WITH JUST HIGH-LEVEL CIRRUS AHEAD OF NEXT WAVE LOWERING TO 10KFT
AT NY TERMINALS AFTER 09Z. AVP WILL BE LAST TO SEE BKN MID-DECK
ARRIVE IN, THUS HAVE GONE PREDOMINANT MVFR VSBYS AFTER 09Z AT THIS
TERMINAL. CONTINUE TO HAVE VERY LITTLE CONFIDENCE IN SHOWER
CHANCES TODAY AND WILL WITHHOLD FROM ANY TEMPO GROUPS UNTIL THEY
ACTUALLY DEVELOP.
WINDS LGT/VRB THIS MORNING WILL INCREASE TO BETWEEN 5-8 KTS OUT OF THE
SOUTHWEST BY MID-MORNING, DIMINISHING LATE IN THE DAY.
OUTLOOK...
SUN THROUGH TUE NGT...POTENTIAL RESTRICTIONS FROM SHRA/TSRA.
WED...PRIMARILY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...RRM
SHORT TERM...
LONG TERM...HEDEN
AVIATION...PVN
AREA FORECAST DISCUSSION
NWS BISMARCK ND
101 PM CDT SAT JUL 12 2014
.UPDATE...
ISSUED AT 100 PM CDT SAT JUL 12 2014
QUICK UPDATE TO REDUCE POPS TO SLIGHT CHC ACROSS ALL OF SOUTHERN
NORTH DAKOTA. LATEST HRRR AND 12Z WRF SHOWS POTENTIAL FOR ISOLATED
SHOWERS AND THUNDERSTORMS CENTRAL NORTH DAKOTA THIS AFTERNOON AND
HAVE EXPANDED THIS AREA FARTHER NORTH FROM PREVIOUS THOUGHTS. IN
ADDITION...IN COLLABORATING WITH GRAND FORKS...THE HRRR ALSO SHOWS
POTENTIAL FOR STRONG WIND GUSTS OVER BOTTINEAU AND ROLETTE COUNTIES
BY MID TO LATE AFTERNOON ALONG AND AHEAD OF MAIN CONVECTION NOW
OCCURRING FROM YORKTON SASKATCHEWAN INTO BRANDON MANITOBA. UPDATES
OUT SHORTLY.
UPDATE ISSUED AT 1149 AM CDT SAT JUL 12 2014
LATEST LOCAL RADAR SHOWS RAIN SHOWERS EXITING DICKEY COUNTY AS
UPPER LEVEL JET STREAK SHIFTS SOUTH AND EAST ACROSS MINNESOTA AND
INTO THE GREAT LAKES. NAM BUFKIT SOUNDINGS AND HRRR PRECIPITATION
FORECAST SHOWS SURFACE HEATING TODAY MAY ALLOW FOR ISOLATED
SHOWERS/THUNDERSTORMS TO DEVELOP ACROSS THE SOUTH AND WILL
MAINTAIN AN ISOLATED THREAT THROUGH 00Z. FARTHER NORTH...SURFACE
COLD FRONT INTO SOUTH CENTRAL MANITOBA WITH 3HR PRESSURE FALLS
CROSSING THE NORTHERN BORDER. POWERFUL JET 100KT JET STREAM WILL
SLIDE ACROSS THE TURTLE MOUNTAINS THROUGH 00Z SUNDAY. BEST JET
DYNAMICS RESIDES EAST OF THE TURTLE MOUNTAINS...HOWEVER FORECAST
0-6KM SHEAR STILL VERY IMPRESSIVE AT AROUND 65KT. CAPE/INSTABILITY
REMAINS MEAGER...BUT THE SHEAR MAY OVERCOME THIS AND WILL NEED TO
WATCH FOR A FEW STRONG TO SEVERE STORMS MID TO LATE AFTERNOON.
HRRR ADVERTISES A FEW CELLS OVER THE TURTLE MOUNTAINS BETWEEN 22Z
AND 02Z...BUT HIGHEST REFLECTIVITY`S REMAIN EAST.
UPDATE ISSUED AT 816 AM CDT SAT JUL 12 2014
LATEST WATER VAPOR IMAGERY ALONG WITH REGIONAL RADAR CONTINUES TO
SHOW UPWARD VERTICAL MOTION WITH RESULTANT RAIN SHOWERS OVER
SOUTH CENTRAL NORTH DAKOTA. RAIN SHOWERS WERE BECOMING MORE
ISOLATED IN EASTERN MONTANA AND SOUTHWEST NORTH DAKOTA. AS
MENTIONED IN THE PREVIOUS DISCUSSION...THE RIGHT ENTRANCE REGION
OF A 110KT JET STREAK/DIVERGENCE ALOFT INTERACTING WITH A FRONT
OVER CENTRAL/NORTHERN SOUTH DAKOTA WILL GRADUALLY ADVANCE FARTHER
EAST AND SOUTH THIS MORNING. THIS WILL SHIFT THE BULK OF THE
SHOWERS INTO THE JAMES RIVER VALLEY BY LATE MORNING. AN ELONGATED
SHORTWAVE OVER NORTH CENTRAL MONTANA WILL SLIDE SOUTHEAST INTO
NORTHWEST/NORTHERN SOUTH DAKOTA BY 18Z...AND THUS WILL MAINTAIN A
MENTION OF SHOWERS INTO THE SOUTHWEST AND SOUTHERN NORTH DAKOTA
THROUGH 18Z THEN BEGIN TO TAPER POPS OFF.
OTHERWISE...CONTINUED MOSTLY CLEAR AND DRY IN THE NORTH THIS MORNING.
WILL MONITOR THE FAR NORTH CENTRAL/TURTLE MOUNTAINS ESPECIALLY BY
MID TO LATE AFTERNOON AS STRONG TO SEVERE THUNDERSTORMS MAY DEVELOP
AHEAD OF A SHARP COLD FRONT. WILL AWAIT THE 12Z DATA...BUT IT
APPEARS THE BEST JET DYNAMICS JUST GRAZES THE TURTLE MOUNTAINS
LATE THIS AFTERNOON/EARLY EVENING. MADE MINOR ADJUSTMENTS TO
POPS/PRECIPITATION AREA BASED ON CURRENT RADAR AND SURFACE OBS.
OVERALL GRIDDED FORECAST IS IN GOOD SHAPE.
UPDATE ISSUED AT 608 AM CDT SAT JUL 12 2014
MAIN CHANGES ARE TO ADJUST POPS TOWARDS CURRENT TRENDS FOR THE
AREA OF SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS CURRENTLY
PUSHING FROM SOUTHWEST INTO SOUTH CENTRAL SOUTH DAKOTA...AND TO
ACCOUNT FOR A FEW SHOWERS AND STORMS TRYING TO PUSH INTO WEST-
CENTRAL NORTH DAKOTA. EXPECT COVERAGE WITH BOTH OF THESE TO
DECREASE LATER THIS MORNING AS RIGHT ENTRANCE REGION OF UPPER JET
SHIFTS TOWARDS THE SOUTHEAST. UPDATES HAVE BEEN SENT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 320 AM CDT SAT JUL 12 2014
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE CHANCES FOR
SHOWERS AND THUNDERSTORMS AGAIN TODAY AND THIS EVENING.
CURRENTLY...FORCING ASSOCIATED WITH THE RIGHT ENTRANCE REGION OF
AN UPPER LEVEL JET STREAK COUPLED WITH A SURFACE BOUNDARY
STRETCHED FROM ACROSS EASTERN MONTANA BACK EAST TO ALONG THE ND/SD
BORDER...RESULTS IN AREAS OF SHOWERS AND SCATTERED THUNDERSTORMS
FROM EAST-CENTRAL MONTANA...OVER SOUTHWEST/FAR SOUTH CENTRAL
NORTH DAKOTA...AND ACROSS MUCH OF SOUTH DAKOTA EARLY THIS MORNING.
THIS ACTIVITY WILL BE MAINTAINED ACROSS MY SOUTHWEST AND SLOWLY
EXPAND INTO MY SOUTH CENTRAL COUNTIES NOW THROUGH 15Z AS THE UPPER
JET STREAK CONTINUES EAST ACROSS THE GREAT LAKES REGION.
RIGHT ENTRANCE REGION (DIVERGENCE ALOFT) OF THE UPPER JET WILL
SHIFT SOUTH MORE INTO SOUTH DAKOTA LATER THIS MORNING AND
AFTERNOON...AND SO WILL PRECIPITATION CHANCES.
LATER TODAY...A DEEP CYCLONE WEST OF HUDSON BAY WILL SEND A
SURFACE COLD FRONT INTO SOUTHERN MANITOBA BY 18Z TODAY AND INTO
NORTHERN NORTH DAKOTA BETWEEN 18Z AND 00Z. THE TURTLE MOUNTAINS
WILL BE THE FAVORED AREA FOR ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS MID/LATE AFTERNOON. KEPT SOME LOW POPS AROUND THIS
FAVORED AREA AS WELL. MODELS STILL ADVERTISE IMPRESSIVE 0-6KM
SHEAR...60KT TO 70KT...ACROSS MY NORTHEAST CORNER. WHILE CAPE
REMAINS WEAK RANGING BETWEEN 200 AND 600 J/KG...MY NORTHEASTERN
COUNTIES WILL NEED TO BE WATCHED CLOSELY FOR SEVERE WEATHER
POTENTIAL LATE THIS SATURDAY AFTERNOON AND PERHAPS INTO THE
EVENING AS WELL.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 320 AM CDT SAT JUL 12 2014
ON SUNDAY...DEEP LOW CENTERED OVER WRN ONTARIO CONTINUES ITS
SOUTHERLY PROGRESSION TOWARDS NRN MINNESOTA. MODELS HAVE BEEN PRETTY
CONSISTENT HOW THEY HAVE HANDLED THIS SYSTEM...THOUGH GFS CONTINUES
TO TAKE A SLIGHTLY EASTERLY TRACK. COOLER AIRMASS ASSOCIATED WITH
THIS SYSTEM CONTINUES TO PUSH INTO THE AREA WITH HIGH TEMPERATURES
WELL BELOW AVERAGE.
PRIMARY PUSH OF COLD AIR WILL COME LATE SUNDAY NIGHT INTO EARLY
MONDAY MORNING. HIGH TEMPERATURES ACROSS THE STATE ARE EXPECTED TO
BE IN THE 60S...ABOUT 20 DEGREES BELOW AVERAGE OVER MANY LOCATIONS.
LOW CONTINUES ITS SOUTHERLY DIVE BEFORE IT STARTS TO TAKE AN
EASTERLY TRACK OVER THE GREAT LAKES REGION. WILL KEEP LOW POPS GOING
ON MONDAY OVER CENTRAL/EASTERN NORTH DAKOTA WITH ACTIVE CYCLONIC
FLOW ON BACKSIDE OF LOW.
BY TUESDAY...REGION WILL BE IN NORTHWESTERLY FLOW ALOFT BETWEEN
AFOREMENTIONED LOW SCOOTING OFF TO THE EAST AND RIDGE OVER WESTERN
CONUS...WHILE HIGH PRESSURE REMAINS AT THE SURFACE. DRY CONDITIONS
WITH A BIT MILDER TEMPERATURES EXPECTED.
FOR THE REMAINDER OF THE EXTENDED...TEMPERATURES WILL CONTINUE TO
REBOUND THROUGH MID-WEEK WITH DRY CONDITIONS. BY FRIDAY MODELS
SUGGESTING A MORE ACTIVE PATTERN DEVELOPING...BRINGING PRECIPITATION
CHANCES TO VARIOUS LOCATIONS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1149 AM CDT SAT JUL 12 2014
WEST WINDS WILL SHIFT TO NORTHWEST AT 15KT TO 25KT THROUGH THE TAF
PERIOD AS A STRONG COLD FRONT SLIDES SOUTH FROM MANITOBA. EXPECT
VFR CIGS/VSBYS THROUGH THE TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...NH
LONG TERM...JJS
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1149 AM CDT SAT JUL 12 2014
.UPDATE...
ISSUED AT 1149 AM CDT SAT JUL 12 2014
LATEST LOCAL RADAR SHOWS RAIN SHOWERS EXITING DICKEY COUNTY AS
UPPER LEVEL JET STREAK SHIFTS SOUTH AND EAST ACROSS MINNESOTA AND
INTO THE GREAT LAKES. NAM BUFKIT SOUNDINGS AND HRRR PRECIPITATION
FORECAST SHOWS SURFACE HEATING TODAY MAY ALLOW FOR ISOLATED
SHOWERS/THUNDERSTORMS TO DEVELOP ACROSS THE SOUTH AND WILL
MAINTAIN AN ISOLATED THREAT THROUGH 00Z. FARTHER NORTH...SURFACE
COLD FRONT INTO SOUTH CENTRAL MANITOBA WITH 3HR PRESSURE FALLS
CROSSING THE NORTHERN BORDER. POWERFUL JET 100KT JET STREAM WILL
SLIDE ACROSS THE TURTLE MOUNTAINS THROUGH 00Z SUNDAY. BEST JET
DYNAMICS RESIDES EAST OF THE TURTLE MOUNTAINS...HOWEVER FORECAST
0-6KM SHEAR STILL VERY IMPRESSIVE AT AROUND 65KT. CAPE/INSTABILITY
REMAINS MEAGER...BUT THE SHEAR MAY OVERCOME THIS AND WILL NEED TO
WATCH FOR A FEW STRONG TO SEVERE STORMS MID TO LATE AFTERNOON.
HRRR ADVERTISES A FEW CELLS OVER THE TURTLE MOUNTAINS BETWEEN 22Z
AND 02Z...BUT HIGHEST REFLECTIVITY`S REMAIN EAST.
UPDATE ISSUED AT 816 AM CDT SAT JUL 12 2014
LATEST WATER VAPOR IMAGERY ALONG WITH REGIONAL RADAR CONTINUES TO
SHOW UPWARD VERTICAL MOTION WITH RESULTANT RAIN SHOWERS OVER
SOUTH CENTRAL NORTH DAKOTA. RAIN SHOWERS WERE BECOMING MORE
ISOLATED IN EASTERN MONTANA AND SOUTHWEST NORTH DAKOTA. AS
MENTIONED IN THE PREVIOUS DISCUSSION...THE RIGHT ENTRANCE REGION
OF A 110KT JET STREAK/DIVERGENCE ALOFT INTERACTING WITH A FRONT
OVER CENTRAL/NORTHERN SOUTH DAKOTA WILL GRADUALLY ADVANCE FARTHER
EAST AND SOUTH THIS MORNING. THIS WILL SHIFT THE BULK OF THE
SHOWERS INTO THE JAMES RIVER VALLEY BY LATE MORNING. AN ELONGATED
SHORTWAVE OVER NORTH CENTRAL MONTANA WILL SLIDE SOUTHEAST INTO
NORTHWEST/NORTHERN SOUTH DAKOTA BY 18Z...AND THUS WILL MAINTAIN A
MENTION OF SHOWERS INTO THE SOUTHWEST AND SOUTHERN NORTH DAKOTA
THROUGH 18Z THEN BEGIN TO TAPER POPS OFF.
OTHERWISE...CONTINUED MOSTLY CLEAR AND DRY IN THE NORTH THIS MORNING.
WILL MONITOR THE FAR NORTH CENTRAL/TURTLE MOUNTAINS ESPECIALLY BY
MID TO LATE AFTERNOON AS STRONG TO SEVERE THUNDERSTORMS MAY DEVELOP
AHEAD OF A SHARP COLD FRONT. WILL AWAIT THE 12Z DATA...BUT IT
APPEARS THE BEST JET DYNAMICS JUST GRAZES THE TURTLE MOUNTAINS
LATE THIS AFTERNOON/EARLY EVENING. MADE MINOR ADJUSTMENTS TO
POPS/PRECIPITATION AREA BASED ON CURRENT RADAR AND SURFACE OBS.
OVERALL GRIDDED FORECAST IS IN GOOD SHAPE.
UPDATE ISSUED AT 608 AM CDT SAT JUL 12 2014
MAIN CHANGES ARE TO ADJUST POPS TOWARDS CURRENT TRENDS FOR THE
AREA OF SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS CURRENTLY
PUSHING FROM SOUTHWEST INTO SOUTH CENTRAL SOUTH DAKOTA...AND TO
ACCOUNT FOR A FEW SHOWERS AND STORMS TRYING TO PUSH INTO WEST-
CENTRAL NORTH DAKOTA. EXPECT COVERAGE WITH BOTH OF THESE TO
DECREASE LATER THIS MORNING AS RIGHT ENTRANCE REGION OF UPPER JET
SHIFTS TOWARDS THE SOUTHEAST. UPDATES HAVE BEEN SENT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 320 AM CDT SAT JUL 12 2014
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE CHANCES FOR
SHOWERS AND THUNDERSTORMS AGAIN TODAY AND THIS EVENING.
CURRENTLY...FORCING ASSOCIATED WITH THE RIGHT ENTRANCE REGION OF
AN UPPER LEVEL JET STREAK COUPLED WITH A SURFACE BOUNDARY
STRETCHED FROM ACROSS EASTERN MONTANA BACK EAST TO ALONG THE ND/SD
BORDER...RESULTS IN AREAS OF SHOWERS AND SCATTERED THUNDERSTORMS
FROM EAST-CENTRAL MONTANA...OVER SOUTHWEST/FAR SOUTH CENTRAL
NORTH DAKOTA...AND ACROSS MUCH OF SOUTH DAKOTA EARLY THIS MORNING.
THIS ACTIVITY WILL BE MAINTAINED ACROSS MY SOUTHWEST AND SLOWLY
EXPAND INTO MY SOUTH CENTRAL COUNTIES NOW THROUGH 15Z AS THE UPPER
JET STREAK CONTINUES EAST ACROSS THE GREAT LAKES REGION.
RIGHT ENTRANCE REGION (DIVERGENCE ALOFT) OF THE UPPER JET WILL
SHIFT SOUTH MORE INTO SOUTH DAKOTA LATER THIS MORNING AND
AFTERNOON...AND SO WILL PRECIPITATION CHANCES.
LATER TODAY...A DEEP CYCLONE WEST OF HUDSON BAY WILL SEND A
SURFACE COLD FRONT INTO SOUTHERN MANITOBA BY 18Z TODAY AND INTO
NORTHERN NORTH DAKOTA BETWEEN 18Z AND 00Z. THE TURTLE MOUNTAINS
WILL BE THE FAVORED AREA FOR ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS MID/LATE AFTERNOON. KEPT SOME LOW POPS AROUND THIS
FAVORED AREA AS WELL. MODELS STILL ADVERTISE IMPRESSIVE 0-6KM
SHEAR...60KT TO 70KT...ACROSS MY NORTHEAST CORNER. WHILE CAPE
REMAINS WEAK RANGING BETWEEN 200 AND 600 J/KG...MY NORTHEASTERN
COUNTIES WILL NEED TO BE WATCHED CLOSELY FOR SEVERE WEATHER
POTENTIAL LATE THIS SATURDAY AFTERNOON AND PERHAPS INTO THE
EVENING AS WELL.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 320 AM CDT SAT JUL 12 2014
ON SUNDAY...DEEP LOW CENTERED OVER WRN ONTARIO CONTINUES ITS
SOUTHERLY PROGRESSION TOWARDS NRN MINNESOTA. MODELS HAVE BEEN PRETTY
CONSISTENT HOW THEY HAVE HANDLED THIS SYSTEM...THOUGH GFS CONTINUES
TO TAKE A SLIGHTLY EASTERLY TRACK. COOLER AIRMASS ASSOCIATED WITH
THIS SYSTEM CONTINUES TO PUSH INTO THE AREA WITH HIGH TEMPERATURES
WELL BELOW AVERAGE.
PRIMARY PUSH OF COLD AIR WILL COME LATE SUNDAY NIGHT INTO EARLY
MONDAY MORNING. HIGH TEMPERATURES ACROSS THE STATE ARE EXPECTED TO
BE IN THE 60S...ABOUT 20 DEGREES BELOW AVERAGE OVER MANY LOCATIONS.
LOW CONTINUES ITS SOUTHERLY DIVE BEFORE IT STARTS TO TAKE AN
EASTERLY TRACK OVER THE GREAT LAKES REGION. WILL KEEP LOW POPS GOING
ON MONDAY OVER CENTRAL/EASTERN NORTH DAKOTA WITH ACTIVE CYCLONIC
FLOW ON BACKSIDE OF LOW.
BY TUESDAY...REGION WILL BE IN NORTHWESTERLY FLOW ALOFT BETWEEN
AFOREMENTIONED LOW SCOOTING OFF TO THE EAST AND RIDGE OVER WESTERN
CONUS...WHILE HIGH PRESSURE REMAINS AT THE SURFACE. DRY CONDITIONS
WITH A BIT MILDER TEMPERATURES EXPECTED.
FOR THE REMAINDER OF THE EXTENDED...TEMPERATURES WILL CONTINUE TO
REBOUND THROUGH MID-WEEK WITH DRY CONDITIONS. BY FRIDAY MODELS
SUGGESTING A MORE ACTIVE PATTERN DEVELOPING...BRINGING PRECIPITATION
CHANCES TO VARIOUS LOCATIONS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1149 AM CDT SAT JUL 12 2014
WEST WINDS WILL SHIFT TO NORTHWEST AT 15KT TO 25KT THROUGH THE TAF
PERIOD AS A STRONG COLD FRONT SLIDES SOUTH FROM MANITOBA. EXPECT
VFR CIGS/VSBYS THROUGH THE TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...NH
LONG TERM...JJS
AVIATION...KS
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
540 PM EDT SAT JUL 12 2014
.SYNOPSIS...
WEAK HIGH PRESSURE WILL LINGER OVER THE WESTERN CAROLINAS AND
NORTHEAST GEORGIA THE REST OF THE WEEKEND. AN UNSEASONABLY STRONG
COLD FRONT WILL APPROACH THE AREA FROM THE NORTHWEST ON MONDAY AND
CROSS THE REGION TUESDAY. COOLER THAN NORMAL TEMPERATURES WILL
ARRIVE FROM MID TO LATE WEEK BEHIND THE FRONT.
&&
.NEAR TERM /THROUGH SUNDAY/...
AS 530 PM...THE CURRENT FORECAST REMAINS IN GREAT SHAPE. SCT
CONVECTION OVER THE MTNS HAS TRENDED WEAKER OVER THE PAST HOUR...BUT
COVERAGE HAS REMAINED NEARLY UNCHANGED. I WILL UPDATE THE FORECAST
TO ALIGN SKY WITH SATELLITE OBSERVATIONS AND TO TWEAK TEMPS.
OTHERWISE...CHANGES TO FORECAST WILL BE MINOR.
AT 245 PM EDT SATURDAY... CURRENT MESOANALYSIS INDICATES CAPES OVER
THE MOUNTAINS ARE AROUND 1500 J/KG AND GENERALLY LESS THAN 1000 J/KG
EAST OF THE MOUNTAINS. RAP FORECAST INTO THE EVENING SHOWS CAPE
PERSISTS FOR A WHILE IN THE FAR WESTERN ZONES... ALIGNED WITH THE
AXIS OF HIGH TERRAIN... BUT CAPE DECREASES SUBSTANTIALLY IN THE
EAST. AS HAS BEEN THE CASE DURING THE PAST COUPLE OF NIGHTS...
ISOLATED CONVECTIVE STORMS MIGHT CONTINUE WELL AFTER SUNSET. VERY
LIGHT WINDS THROUGH A DEEP LAYER COULD RESULT IN SLOWLY MOVING
THUNDERSTORMS AND THE POTENTIAL FOR LOCALLY EXCESSIVE RAINFALL.
OTHERWISE... PRIMARY FEATURE ALOFT AFFECTING OUR WEATHER THROUGH
SUNDAY IS A RIDGE EXTENDING FROM THE WEST COAST ACROSS THE SOUTHERN
STATES TO THE CAROLINAS. AT THE SURFACE... HIGH PRESSURE WITH A VERY
WEAK GRADIENT WILL COVER THE REGION. AS HEIGHTS FALL OVER THE
NORTHERN U.S. ON SUNDAY... THE EASTERN PERIPHERY OF THE UPPER LEVEL
RIDGE WILL WITHDRAW WESTWARD A BIT... BUT THROUGH TOMORROW THE RIDGE
IS GOING TO BE THE PRIMARY PLAYER IN CONTINUING THE CURRENT PERIOD
OF GENERALLY TRANQUIL WEATHER. THE AIR MASS OVER THE WESTERN ZONES
WILL REMAIN FAIRLY MOIST AND MODERATELY UNSTABLE THUS SUPPORTING
SCATTERED SHOWERS AND THUNDERSTORMS WHICH WILL BE MOST NUMEROUS OVER
THE HIGHER TERRAIN. CAPE VALUES EAST OF THE MOUNTAINS ON SUNDAY WILL
BE HELD AT BAY BY A RATHER WARM TEMPERATURE PROFILE. AN ISOLATED
SHOWER OR THUNDERSTORM IS POSSIBLE... BUT CUMULUS AND TOWERING
CUMULUS SHOULD DOMINATE THE SKY IN OUR PIEDMONT ZONES TOMORROW. LOWS
WILL BE AROUND 70 IN THE PIEDMONT AND IN THE 60S IN THE MOUNTAINS.
HIGHS ON SUNDAY WILL BE FAIRLY CLOSE TO NORMAL... PERHAPS A FEW
DEGREES ABOVE NORMAL AT A FEW LOCATIONS. HIGHS WILL BE AROUND 90
EAST OF THE MOUNTAINS AND IN THE LOWER AND MID 80S IN THE MOUNTAIN
VALLEYS.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
AS OF 230 PM EDT SATURDAY...THE SHORT RANGE PERIOD INITIALIZES
SUNDAY EVENING WITH A BROAD LONGWAVE UPPER TROF ROTATING ACROSS
SOUTHERN ONTARIO. MEANWHILE...BERMUDA HIGH WILL CONTINUE TO ADVECT
WARM/MOIST AIR ACROSS THE SOUTHEAST...NORTHWARD INTO THE MID
ATLANTIC STATES. EXPECTING ONGOING CONVECTION ACROSS THE HIGH
TERRAIN AT FORECAST INITIALIZATION DUE TO IMPROVED INSTABILITY AXIS
AND WEAK SOUTHERLY UPSLOPE FLOW. CHANCE LEVEL POPS WILL BE
FEATURED INITIALLY ACROSS THE HIGH TERRAIN BEFORE TAPERING DOWN TO
SLIGHT CHANCE LEVELS BY DAYBREAK. BY MONDAY MORNING...THE
FIRST...AND WEAKER OF TWO COLD FRONTAL BOUNDARIES WILL APPROACH THE
REGION FROM THE WEST. ADJACENT WEAK UPPER IMPULSE COMBINED WITH
BOUNDARY INTRUSION WILL SPAWN CONVECTION ACROSS THE
MOUNTAINS/FOOTHILLS DURING THE AFTERNOON HOURS ON MONDAY. DUE TO
THE SUSTAINED SOUTHERLY FLOW IN DAYS PAST...THE ATMOSPHERE WILL HAVE
RECOVERED ENOUGH TO YIELD A MODERATELY UNSTABLE WARM SECTOR AHEAD OF
THIS FRONT. THUS...EXPECTING SHOWERS AND THUNDERSTORMS TO SPILL OUT
OF THE HIGH TERRAIN AND PROPAGATE EAST INTO THE PIEDMONT/FOOTHILLS
MONDAY EVENING. AS SAID ABOVE...SUBSTANTIAL CAPE WILL BE PRESENT TO
SUPPORT SOME DEEPER UPDRAFTS LEADING TO A FEW STRONG/SEVERE
THUNDERSTORMS MONDAY AFTERNOON/EVENING...DESPITE WEAKER YET
IMPROVING SHEAR. FORECAST WILL FEATURE LIKELY POPS ACROSS THE
MAJORITY OF THE MOUNTAIN/FOOTHILLS ZONES WHILE LOWER CHANCE POPS ARE
HIGHLIGHTED SOUTH EASTWARD ACROSS NORTHEAST GA AND THE NC/SC
PIEDMONTS.
TUESDAY MORNING THE ABOVE MENTIONED BOUNDARY WILL HAVE ESSENTIALLY
DISSIPATED AND BECOME STATIONARY ACROSS CENTRAL NC...SOUTHWARD
INTO THE MIDLANDS OF SC. AT THE SAME TIME THE RATHER
DEEP/IMPRESSIVE UPPER LOW WILL ROTATE DOWN ACROSS THE GREAT LAKES
WHILE SURFACE CYCLOGENESIS OCCURS ALONG THE EASTERN SEABOARD. THE
STRONG COLD FRONT WILL BE PUSHING THROUGH THE OHIO VALLEY BY EARLY
MORNING...EASTWARD INTO THE CENTRAL/SOUTHERN APPS BY MID/LATE
MORNING...THEN FINALLY FURTHER EAST INTO THE PIEDMONT REGIONS ON
TUESDAY AFTERNOON/EVENING. EXPECTING THE ABOVE MENTIONED SURFACE
CYCLONE TO DEEPEN SLIGHTLY AND AID IN DEVELOPMENT OF A LEE SIDE
TROF ACROSS THE PIEDMONT/COASTAL PLAINS OF NC LATE IN THE
AFTERNOON. THIS WEAK/DIFFUSE BOUNDARY COULD PROVIDE A FOCUS FOR
SURFACE CONVERGENCE AHEAD OF THE APPROACHING/STRONG COLD FRONT.
THERE WILL BE SUFFICIENT UPPER SUPPORT...SHEAR...AND BUOYANCY IN
PLACE TO SUPPORT ORGANIZED STRONG/SEVERE CONVECTION ACROSS THE
ENTIRE REGION ON TUESDAY. THE FORECAST WILL FEATURE WIDESPREAD
LIKELY POPS FOR TUESDAY ENCOMPASSING THE ENTIRE REGION. WILL
CONTINUE WITH SEVERE THUNDERSTORM POSSIBLE WORDING IN THE HWO FOR
BOTH MONDAY EVENING/OVERNIGHT...AND THROUGH THE DAY ON TUESDAY.
TEMPERATURES WILL BE ABOVE NORMAL ON MONDAY AS DEEP SOUTHERLY FLOW
PREVAILS AMONGST PARTLY CLOUDY SKIES WHILE MOSTLY CLOUDY SKIES
COMBINE WITH PRECIPITATION TO KEEP HIGHS A FEW DEGREES BELOW NORMAL
FOR TUESDAY. BY WEDNESDAY MORNING...THE FRONT WILL BE EXITING TO
THE EAST ALLOWING FOR POPS TO TREND DOWN...ALONG WITH TEMPS. LOWS
ON WEDNESDAY MORNING WILL REMAIN AT OR JUST BELOW NORMAL ACROSS THE
LOWER TERRAIN WHERE THE FROPA OCCURS LATER...WHILE THE HIGH TERRAIN
WILL SEE LOWS ON THE ORDER OF 5 DEGREES BELOW NORMAL.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 130 PM SAT...A BROAD TROUGH WILL BE IN PLACE ACROSS THE ERN
TWO THIRDS OF THE CONUS ON WED AS A DEEP LOW PRESSURE SYSTEM SPINS
OVER ERN CANADA AND THE NRN GREAT LAKES. DEEP LAYER DRYING IS
EXPECTED ON WEDNESDAY BEHIND THE SLOWLY DEPARTING/STALLING COLD
FRONT...WITH MAINLY NW FLOW ACROSS THE REGION. WEAK SFC HIGH PRES
WILL BUILD OVER FROM THE N...AND MAX TEMPS SHOULD DIP TO TWO
CATEGORIES BELOW NORMAL BY WED AFTN. AS THE WEAK HIGH SETTLES INTO
PLACE TO OUR N...LOW LEVEL EASTERLY FLOW COULD DEVELOP INTO THE SRN
APPALACHIANS BY THU. IT IS QUESTIONABLE HOW MUCH MOISTURE WILL
RETURN TO THE PROFILES...BUT SLIGHTLY IMPROVED BL RH COULD HELP
TRIGGER ISOLD TO SCT AFTN SHOWERS...ESPECIALLY IN AND NEAR THE MTNS.
MAX TEMPS LOOK TO BE A SOLID 5 TO 10 DEGREES BELOW NORMAL THU
AFTN...POSSIBLY MORE IF WE CLOUD UP QUICKER.
THOUGH SUBTLE MODEL DIFFERENCES EXIST BY LATE WEEK...THERE IS
REASONABLE CONSENSUS REGARDING SHORTWAVE ENERGY DIVING THROUGH THE
SRN PLAINS INTO THE BROAD TROUGH ON THU...AND THEN MOVING TO THE
BASE OF THE SRN APPALACHIANS BY FRI. THIS MAY BRING A WEAK SFC
REFLECTION AND ADDITIONAL MOISTURE BACK TO THE REGION...INTERACTING
WITH THE WEAK SFC HIGH TO THE NORTH AND POSSIBLY PROVIDING SOME
DEGREE OF COLD AIR DAMMING FRI INTO SAT. WILL KEEP MAXES WELL BELOW
NORMAL DURING THIS PERIOD...WITH MAINLY CHC POPS...HIGHEST NEAR THE
BLUE RIDGE.
&&
.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
AT KCLT... SCATTERED TO BROKEN CU AND TCU 4-6K WILL CONTINUE THROUGH
THE AFTERNOON THEN GRADUALLY DISSIPATE AROUND SUNSET. VISIBILITY
UNRESTRICTED EXCEPT 5 MILES IN HAZE NEAR SUNRISE. BY MID TO LATE
MORNING SUNDAY... SCATTERED CU 4-6K FT WILL DEVELOP AND VISIBILITY
WILL BECOME UNRESTRICTED. SURFACE WIND WILL REMAIN LIGHT SOUTHEAST
BECOMING LIGHT AND VARIABLE OVERNIGHT.
ELSEWHERE... SCATTERED TO BROKEN CU AND TCU 4-6K WILL PTHROUGH THE
AFTERNOON THEN GRADUALLY DISSIPATE AFTER SUNSET. MODEL PROFILES
INDICATE VERY LITTLE CAPE AVAILABLE FOR STRONG UPDRAFTS EXCEPT OVER
THE MOUNTAINS WHERE WIDELY SCATTERED THUNDERSTORMS ARE POSSIBLE.
ISOLATED THUNDERSTORMS COULD PERSIST UNTIL MIDNIGHT. CONVECTIVE
STORMS WILL BE MOST NUMEROUS NORTH AND WEST OF KAVL... SO WILL NOT
INCLUDE IN TAF UNLESS OCCURRENCE BECOMES MORE LIKELY. VALLEY FOG
LIKELY TO BEGIN FORMING AFTER 06Z WHICH WILL RESULT IN LIFR AT KAVL.
VISIBILITY EXPECTED TO BECOME UNRESTRICTED AT KAVL BY 14Z.
OUTLOOK...RESTRICTIONS IN THUNDERSTORMS ARE POSSIBLE MONDAY AND
TUESDAY. UNLIMITED CEILING AND UNRESTRICTED VISIBILITY WILL RETURN
ON WEDNESDAY FOLLOWING COLD FRONTAL PASSAGE.
CONFIDENCE TABLE...
21-03Z 03-09Z 09-15Z 15-21Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 81%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 81%
KAVL HIGH 100% HIGH 87% HIGH 88% MED 75%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 81%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 81%
KAND HIGH 100% HIGH 100% HIGH 87% HIGH 81%
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...HG
NEAR TERM...LGL/NED
SHORT TERM...CDG
LONG TERM...HG
AVIATION...LGL
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
251 PM EDT SAT JUL 12 2014
.SYNOPSIS...
WEAK HIGH PRESSURE WILL LINGER OVER THE WESTERN CAROLINAS AND
NORTHEAST GEORGIA THE REST OF THE WEEKEND. AN UNSEASONABLY STRONG
COLD FRONT WILL APPROACH THE AREA FROM THE NORTHWEST ON MONDAY AND
CROSS THE REGION TUESDAY. COOLER THAN NORMAL TEMPERATURES WILL
ARRIVE FROM MID TO LATE WEEK BEHIND THE FRONT.
&&
.NEAR TERM /THROUGH SUNDAY/...
AT 245 PM EDT SATURDAY... CURRENT MESOANALYSIS INDICATES CAPES OVER
THE MOUNTAINS ARE AROUND 1500 J/KG AND GENERALLY LESS THAN 1000 J/KG
EAST OF THE MOUNTAINS. RAP FORECAST INTO THE EVENING SHOWS CAPE
PERSISTS FOR A WHILE IN THE FAR WESTERN ZONES... ALIGNED WITH THE
AXIS OF HIGH TERRAIN... BUT CAPE DECREASES SUBSTANTIALLY IN THE
EAST. AS HAS BEEN THE CASE DURING THE PAST COUPLE OF NIGHTS...
ISOLATED CONVECTIVE STORMS MIGHT CONTINUE WELL AFTER SUNSET. VERY
LIGHT WINDS THROUGH A DEEP LAYER COULD RESULT IN SLOWLY MOVING
THUNDERSTORMS AND THE POTENTIAL FOR LOCALLY EXCESSIVE RAINFALL.
OTHERWISE... PRIMARY FEATURE ALOFT AFFECTING OUR WEATHER THROUGH
SUNDAY IS A RIDGE EXTENDING FROM THE WEST COAST ACROSS THE SOUTHERN
STATES TO THE CAROLINAS. AT THE SURFACE... HIGH PRESSURE WITH A VERY
WEAK GRADIENT WILL COVER THE REGION. AS HEIGHTS FALL OVER THE
NORTHERN U.S. ON SUNDAY... THE EASTERN PERIPHERY OF THE UPPER LEVEL
RIDGE WILL WITHDRAW WESTWARD A BIT... BUT THROUGH TOMORROW THE RIDGE
IS GOING TO BE THE PRIMARY PLAYER IN CONTINUING THE CURRENT PERIOD
OF GENERALLY TRANQUIL WEATHER. THE AIR MASS OVER THE WESTERN ZONES
WILL REMAIN FAIRLY MOIST AND MODERATELY UNSTABLE THUS SUPPORTING
SCATTERED SHOWERS AND THUNDERSTORMS WHICH WILL BE MOST NUMEROUS OVER
THE HIGHER TERRAIN. CAPE VALUES EAST OF THE MOUNTAINS ON SUNDAY WILL
BE HELD AT BAY BY A RATHER WARM TEMPERATURE PROFILE. AN ISOLATED
SHOWER OR THUNDERSTORM IS POSSIBLE... BUT CUMULUS AND TOWERING
CUMULUS SHOULD DOMINATE THE SKY IN OUR PIEDMONT ZONES TOMORROW. LOWS
WILL BE AROUND 70 IN THE PIEDMONT AND IN THE 60S IN THE MOUNTAINS.
HIGHS ON SUNDAY WILL BE FAIRLY CLOSE TO NORMAL... PERHAPS A FEW
DEGREES ABOVE NORMAL AT A FEW LOCATIONS. HIGHS WILL BE AROUND 90
EAST OF THE MOUNTAINS AND IN THE LOWER AND MID 80S IN THE MOUNTAIN
VALLEYS.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
AS OF 230 PM EDT SATURDAY...THE SHORT RANGE PERIOD INITIALIZES
SUNDAY EVENING WITH A BROAD LONGWAVE UPPER TROF ROTATING ACROSS
SOUTHERN ONTARIO. MEANWHILE...BERMUDA HIGH WILL CONTINUE TO ADVECT
WARM/MOIST AIR ACROSS THE SOUTHEAST...NORTHWARD INTO THE MID
ATLANTIC STATES. EXPECTING ONGOING CONVECTION ACROSS THE HIGH
TERRAIN AT FORECAST INITIALIZATION DUE TO IMPROVED INSTABILITY AXIS
AND WEAK SOUTHERLY UPSLOPE FLOW. CHANCE LEVEL POPS WILL BE
FEATURED INITIALLY ACROSS THE HIGH TERRAIN BEFORE TAPERING DOWN TO
SLIGHT CHANCE LEVELS BY DAYBREAK. BY MONDAY MORNING...THE
FIRST...AND WEAKER OF TWO COLD FRONTAL BOUNDARIES WILL APPROACH THE
REGION FROM THE WEST. ADJACENT WEAK UPPER IMPULSE COMBINED WITH
BOUNDARY INTRUSION WILL SPAWN CONVECTION ACROSS THE
MOUNTAINS/FOOTHILLS DURING THE AFTERNOON HOURS ON MONDAY. DUE TO
THE SUSTAINED SOUTHERLY FLOW IN DAYS PAST...THE ATMOSPHERE WILL HAVE
RECOVERED ENOUGH TO YIELD A MODERATELY UNSTABLE WARM SECTOR AHEAD OF
THIS FRONT. THUS...EXPECTING SHOWERS AND THUNDERSTORMS TO SPILL OUT
OF THE HIGH TERRAIN AND PROPAGATE EAST INTO THE PIEDMONT/FOOTHILLS
MONDAY EVENING. AS SAID ABOVE...SUBSTANTIAL CAPE WILL BE PRESENT TO
SUPPORT SOME DEEPER UPDRAFTS LEADING TO A FEW STRONG/SEVERE
THUNDERSTORMS MONDAY AFTERNOON/EVENING...DESPITE WEAKER YET
IMPROVING SHEAR. FORECAST WILL FEATURE LIKELY POPS ACROSS THE
MAJORITY OF THE MOUNTAIN/FOOTHILLS ZONES WHILE LOWER CHANCE POPS ARE
HIGHLIGHTED SOUTH EASTWARD ACROSS NORTHEAST GA AND THE NC/SC
PIEDMONTS.
TUESDAY MORNING THE ABOVE MENTIONED BOUNDARY WILL HAVE ESSENTIALLY
DISSIPATED AND BECOME STATIONARY ACROSS CENTRAL NC...SOUTHWARD
INTO THE MIDLANDS OF SC. AT THE SAME TIME THE RATHER
DEEP/IMPRESSIVE UPPER LOW WILL ROTATE DOWN ACROSS THE GREAT LAKES
WHILE SURFACE CYCLOGENESIS OCCURS ALONG THE EASTERN SEABOARD. THE
STRONG COLD FRONT WILL BE PUSHING THROUGH THE OHIO VALLEY BY EARLY
MORNING...EASTWARD INTO THE CENTRAL/SOUTHERN APPS BY MID/LATE
MORNING...THEN FINALLY FURTHER EAST INTO THE PIEDMONT REGIONS ON
TUESDAY AFTERNOON/EVENING. EXPECTING THE ABOVE MENTIONED SURFACE
CYCLONE TO DEEPEN SLIGHTLY AND AID IN DEVELOPMENT OF A LEE SIDE
TROF ACROSS THE PIEDMONT/COASTAL PLAINS OF NC LATE IN THE
AFTERNOON. THIS WEAK/DIFFUSE BOUNDARY COULD PROVIDE A FOCUS FOR
SURFACE CONVERGENCE AHEAD OF THE APPROACHING/STRONG COLD FRONT.
THERE WILL BE SUFFICIENT UPPER SUPPORT...SHEAR...AND BUOYANCY IN
PLACE TO SUPPORT ORGANIZED STRONG/SEVERE CONVECTION ACROSS THE
ENTIRE REGION ON TUESDAY. THE FORECAST WILL FEATURE WIDESPREAD
LIKELY POPS FOR TUESDAY ENCOMPASSING THE ENTIRE REGION. WILL
CONTINUE WITH SEVERE THUNDERSTORM POSSIBLE WORDING IN THE HWO FOR
BOTH MONDAY EVENING/OVERNIGHT...AND THROUGH THE DAY ON TUESDAY.
TEMPERATURES WILL BE ABOVE NORMAL ON MONDAY AS DEEP SOUTHERLY FLOW
PREVAILS AMONGST PARTLY CLOUDY SKIES WHILE MOSTLY CLOUDY SKIES
COMBINE WITH PRECIPITATION TO KEEP HIGHS A FEW DEGREES BELOW NORMAL
FOR TUESDAY. BY WEDNESDAY MORNING...THE FRONT WILL BE EXITING TO
THE EAST ALLOWING FOR POPS TO TREND DOWN...ALONG WITH TEMPS. LOWS
ON WEDNESDAY MORNING WILL REMAIN AT OR JUST BELOW NORMAL ACROSS THE
LOWER TERRAIN WHERE THE FROPA OCCURS LATER...WHILE THE HIGH TERRAIN
WILL SEE LOWS ON THE ORDER OF 5 DEGREES BELOW NORMAL.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 130 PM SAT...A BROAD TROUGH WILL BE IN PLACE ACROSS THE ERN
TWO THIRDS OF THE CONUS ON WED AS A DEEP LOW PRESSURE SYSTEM SPINS
OVER ERN CANADA AND THE NRN GREAT LAKES. DEEP LAYER DRYING IS
EXPECTED ON WEDNESDAY BEHIND THE SLOWLY DEPARTING/STALLING COLD
FRONT...WITH MAINLY NW FLOW ACROSS THE REGION. WEAK SFC HIGH PRES
WILL BUILD OVER FROM THE N...AND MAX TEMPS SHOULD DIP TO TWO
CATEGORIES BELOW NORMAL BY WED AFTN. AS THE WEAK HIGH SETTLES INTO
PLACE TO OUR N...LOW LEVEL EASTERLY FLOW COULD DEVELOP INTO THE SRN
APPALACHIANS BY THU. IT IS QUESTIONABLE HOW MUCH MOISTURE WILL
RETURN TO THE PROFILES...BUT SLIGHTLY IMPROVED BL RH COULD HELP
TRIGGER ISOLD TO SCT AFTN SHOWERS...ESPECIALLY IN AND NEAR THE MTNS.
MAX TEMPS LOOK TO BE A SOLID 5 TO 10 DEGREES BELOW NORMAL THU
AFTN...POSSIBLY MORE IF WE CLOUD UP QUICKER.
THOUGH SUBTLE MODEL DIFFERENCES EXIST BY LATE WEEK...THERE IS
REASONABLE CONSENSUS REGARDING SHORTWAVE ENERGY DIVING THROUGH THE
SRN PLAINS INTO THE BROAD TROUGH ON THU...AND THEN MOVING TO THE
BASE OF THE SRN APPALACHIANS BY FRI. THIS MAY BRING A WEAK SFC
REFLECTION AND ADDITIONAL MOISTURE BACK TO THE REGION...INTERACTING
WITH THE WEAK SFC HIGH TO THE NORTH AND POSSIBLY PROVIDING SOME
DEGREE OF COLD AIR DAMMING FRI INTO SAT. WILL KEEP MAXES WELL BELOW
NORMAL DURING THIS PERIOD...WITH MAINLY CHC POPS...HIGHEST NEAR THE
BLUE RIDGE.
&&
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
AT KCLT... SCATTERED TO BROKEN CU AND TCU 4-6K WILL CONTINUE THROUGH
THE AFTERNOON THEN GRADUALLY DISSIPATE AROUND SUNSET. VISIBILITY
UNRESTRICTED EXCEPT 5 MILES IN HAZE NEAR SUNRISE. BY MID TO LATE
MORNING SUNDAY... SCATTERED CU 4-6K FT WILL DEVELOP AND VISIBILITY
WILL BECOME UNRESTRICTED. SURFACE WIND WILL REMAIN LIGHT SOUTHEAST
BECOMING LIGHT AND VARIABLE OVERNIGHT.
ELSEWHERE... SCATTERED TO BROKEN CU AND TCU 4-6K WILL PTHROUGH THE
AFTERNOON THEN GRADUALLY DISSIPATE AFTER SUNSET. MODEL PROFILES
INDICATE VERY LITTLE CAPE AVAILABLE FOR STRONG UPDRAFTS EXCEPT OVER
THE MOUNTAINS WHERE WIDELY SCATTERED THUNDERSTORMS ARE POSSIBLE.
ISOLATED THUNDERSTORMS COULD PERSIST UNTIL MIDNIGHT. CONVECTIVE
STORMS WILL BE MOST NUMEROUS NORTH AND WEST OF KAVL... SO WILL NOT
INCLUDE IN TAF UNLESS OCCURRENCE BECOMES MORE LIKELY. VALLEY FOG
LIKELY TO BEGIN FORMING AFTER 06Z WHICH WILL RESULT IN LIFR AT KAVL.
VISIBILITY EXPECTED TO BECOME UNRESTRICTED AT KAVL BY 14Z.
OUTLOOK...RESTRICTIONS IN THUNDERSTORMS ARE POSSIBLE MONDAY AND
TUESDAY. UNLIMITED CEILING AND UNRESTRICTED VISIBILITY WILL RETURN
ON WEDNESDAY FOLLOWING COLD FRONTAL PASSAGE.
CONFIDENCE TABLE...
19-01Z 01-07Z 07-13Z 13-19Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 83%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 83%
KAVL HIGH 92% HIGH 91% MED 73% MED 74%
KHKY HIGH 100% HIGH 100% HIGH 97% HIGH 83%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 83%
KAND HIGH 100% HIGH 100% HIGH 88% HIGH 80%
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...HG
NEAR TERM...LGL
SHORT TERM...CDG
LONG TERM...HG
AVIATION...LGL
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
326 PM CDT SAT JUL 12 2014
.DISCUSSION...
TONIGHT INTO TUESDAY...
VERY ISOLATED SHOWERS AND THUNDERSTORMS DEVELOPING ACROSS THE
FORECAST AREA...95 PERCENT OF THE FORECAST WILL SEE NOTHING FROM
THESE...BUT AS THEY ARE DEVELOPING ON RADAR HAVE ADDED PRE-FIRST
PERIOD ISOLATED STORMS TO THE GRIDS. HRRR 3KM MODEL SHOWED THESE
STARTING TO DEVELOP AROUND 20Z...AND THEY DID...MAYBE I SHOULD
"LISTEN" TO THESE NEW HI-RES MODELS AFTER ALL...THOUGHT THE
DRY AIR ALOFT WITH THE RIDGING AND THE CAPPING SEEN ON THE
FORECAST SOUNDINGS ABOVE 700MB WOULD KEEP STORMS FROM
OCCURRING...BUT NOT TODAY AS I GUESS IT WAS OVERCOME WITH THE CAPES
PUSHING 3.5 TO 4.5K J/KG. PRECIP ENDS SHORTLY AFTER SUNSET WITH THE
LOSS OF HEATING AND CLOUDS WILL MOSTLY DISSIPATE WITH CLEAR TO
MOSTLY CLEAR SKIES.
MODELS STILL SHOWING THE WARMER TEMPS FOR TOMORROW WITH DEWPTS
AROUND THE LOWER 70S...PUSHING APPARENT TEMPS INTO THE 100-104
RANGE...OR JUST BELOW THE HEAT ADVISORY CRITERIA...HOTTEST DAY OF
THE YEAR POSSIBLY AND SHOULD BE DRY. THINGS BEGIN TO CHANGE AS WE
MOVE INTO MONDAY...EARLY DURING THE DAY THE DEEP TROUGH WILL START
TO PUSH SOUTH DIGGING INTO THE MIDDLE MS VALLEY...PRE FRONTAL
TROUGH PRECIP POSSIBLE ON MONDAY...SOME CHANCES FOR STRONG TO
SEVERE STORMS MONDAY AFTERNOON AND EVENING...ALL DEPENDING ON
CLOUD COVER AND IF ATMOSPHERE GETS WORKED OVER SOME OR NOT ABLE TO
FULLY DESTABILIZE TO CREATE VERY STRONG STORMS...SOMETHING TO
WATCH. CAPES EXCEED 2 TO 3K J/KG AND MODEST SHEAR...NOTHING OVERLY
EXCITING...BUT POSSIBLE STRONG TO SEVERE. DEEP TROUGH AXIS PUSHES
THROUGH OVERNIGHT MONDAY AND DRIVES THE COLD FRONT INTO NORTHERN
MS BY MID AFTN TUESDAY...BEST CHANCES FOR PRECIP EXISTS MONDAY
NIGHT THROUGH MIDDAY TUESDAY FOR MUCH...IF NOT ALL OF THE AREA.
DECREASING THROUGH THE AFTERNOON AND EVENING FROM NORTH TO SOUTH
AND THE BOUNDARY SAGS. NOT THINKING MUCH CHANCE FOR SEVERE STORMS
ON TUESDAY...BUT SOME MODELS DO SHOW DECENT CAPE STILL IN
PLACE...BUT UPPER LEVEL SUPPORT IS ALMOST NIL WITH UPPER LEVEL LOW
IN QUEBEC.
WEDNESDAY INTO NEXT WEEKEND...
MODELS SHOW DRYING ON WEDNESDAY WITH DECENT NORTHERLY FLOW PUSHING
MUCH COOLER AIR INTO THE REGION...HIGHS NEAR 80 TO THE LOWER
80S...NEARLY 10-15 DEGREES BELOW NORMAL. NORTHERLY FLOW CONTINUES
INTO THURSDAY WITH COOLER THAN NORMAL AND LIKELY DRY CONDITIONS.
MODELS DIVERGE SOME AS WE APPROACH THE WEEKEND...SOME STARTING TO
SHOW AN UPPER LEVEL FEATURE MOVE ACROSS THE REGION FRIDAY INTO
SATURDAY AND CREATING SHOWERS AND THUNDERSTORMS. HAVE LOW POPS IN
AS LITTLE CONSISTENCY SEEN THE LAST TWO DAYS WITH HOW THIS WILL
PLAY OUT WITH THE AMPLIFIED PATTERN OVER THE CONUS BREAKING
DOWN. GFS ENSEMBLE MEAN SHOWS THE REGION WET FRIDAY AND
SATURDAY AND THE EURO ALSO THIS AFTN...AND THAT MAYBE THE LIKELY
TREND TOWARDS A WET FORECAST FOR THOSE DAYS. -ABS
&&
.AVIATION...
18Z TAF CYCLE (12/18Z-13/18Z)
VFR CONDITIONS WILL OCCUR THROUGH THE PERIOD WITH THE EXCEPTION
BEING THE POSSIBILITY OF MVFR VISIBILITIES IN FOG AT KTUP AND KMKL
13/08Z-13/12Z. WINDS THIS AFTERNOON SW 4-7 KTS EXCEPT VRBL 4 KTS AT
KTUP. WINDS TONIGHT S-SW 4 KTS OR LESS. WINDS SUNDAY MORNING SW
4-10 KTS.
JCL
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
407 PM CDT SAT JUL 12 2014
TONIGHT...FORECAST CONFIDENCE MEDIUM.
A PERIOD OF HEAVY RAIN IS EXPECTED ACROSS SOUTHERN WI LATE THIS
AFTERNOON AND EVENING. THE 12-18Z MODELS HAVE COME INTO AGREEMENT ON
THE HIGHEST QPF PLACEMENT BEING OVER SOUTHERN WI. THE LATEST WPC QPF
DAY 1 GRAPHIC REFLECTS THIS WELL.
THE EXTENSIVE CLOUD COVER THIS MORNING HELPED TO KEEP THE SURFACE
FRONT WELL TO OUR SOUTH...AND THUS THE TORNADO CHANCE IS MINIMAL FOR
US. FORECAST SOUNDINGS SHOW LIMITED INSTABILITY OVER SOUTHERN WI DUE
TO THE MOIST ATMOSPHERE AND WEAK MID LEVEL LAPSE RATES...THUS SEVERE
HAIL IS NO LONGER LIKELY. THE ONLY THING LEFT FOR SEVERE POTENTIAL
IS STORM ORGANIZATION DUE TO BULK SHEAR OF 50 KNOTS AND MODERATE LOW
LEVEL LAPSE RATES TO ALLOW FOR STRONG THUNDERSTORM WIND GUSTS.
THE 850MB FRONT HAS CREPT INTO SOUTH CENTRAL WI THIS AFTERNOON PER
THE RAP MODEL ON THE SPC MESOANALYSIS PAGE. THE LEADING EDGE OF THE
PRECIP TRACKING EASTWARD ACROSS SOUTHERN WI THIS AFTERNOON IS
COINCIDENT WITH 850MB WARM AIR ADVECTION...DIFFERENTIAL VORTICITY
ADVECTION...AND UPPER LEVEL DIVERGENCE IN THE RIGHT ENTRANCE REGION
OF THE UPPER JET. THE NARROW TONGUE OF 500-1000 J/KG CAPE OVER SOUTH
CENTRAL WI IS NOT ENOUGH TO SUPPORT SUSTAINED UPDRAFTS...SO ANY OF
THE STRONGER LOOKING SHOWERS ON RADAR DO NOT LAST LONG. IN
ADDITION...THE MOIST PROFILE AND MINIMAL CAPE IN THE ICE GROWTH
REGION IS INHIBITING CHARGE SEPARATION AND THEREFORE LIGHTNING.
PRECIPITABLE WATER VALUES OF 1.9 ARE SPREADING ACROSS SOUTHERN WI
LATE THIS AFTERNOON. UPSTREAM OBSERVATIONS FROM THE LA CROSSE AREA
HAVE REPORTS OF 2 TO 3 INCHES WITHIN 1.5 HR. THAT AREA OF PRECIP...
A 3 TO 4 HOUR PERIOD OF EFFICIENT RAINFALL... WILL TRANSLATE EAST
LATER THIS AFTERNOON FROM 4 PM UNTIL AROUND 11 PM AND AFFECT AREAS
PRIMARILY ALONG AND SOUTH OF I-94. INCLUDING THE DELLS...MADISON AND
MILWAUKEE AREAS AND SOUTH. URBAN AREAS AND CONSTRUCTION AREAS WILL
BE SUSCEPTIBLE TO FLOODING.
THE HEAVY RAIN WILL BE ON THE NORTH SIDE OF THE 850MB THERMAL
BOUNDARY...IN AN AREA OF STRONG 850-700MB FRONTOGENESIS DURING THE
EARLY EVENING HOURS. THAT BOUNDARY WILL BE DROPPING SOUTHEAST THIS
EVENING. WE ARE WEIGHING THE SHORT TERM PRECIP FORECAST HEAVILY ON
THE HRRR GIVEN ITS GOOD PERFORMANCE SO FAR TODAY. IT CONTINUES TO
SHOW DEVELOPMENT OF STRONGER THUNDERSTORMS EARLY THIS EVENING AS THE
UPPER TROUGH DIGS INTO SOUTHERN WI...COINCIDENT WITH UPPER
DIVERGENCE... 700MB OMEGA AND FRONTOGENESIS. THE WRF MODELS SHOW
THIS AS WELL...BUT NOT THE RAP.
GIVEN THE SHORT NATURE OF THE EVENING HEAVY RAIN EVENT... WE ARE
STILL NOT PLANNING ON ISSUING A FLASH FLOOD WATCH AT THIS TIME.
SOUTHERN WI MISSED OUT ON THE EARLY MORNING RAIN THAT HIT THE
CHICAGO AREA SO WE ARE NOT PRE-CONDITIONED FOR FLASH FLOODING. THERE
IS DEFINITELY AN URBAN FLOODING AND PONDING CONCERN...AND WE PLAN TO
HANDLE THE RAIN WITH AN URBAN AND SMALL STREAM FLOOD ADVISORY
HEADLINE AT THIS TIME. OF COURSE...THAT IS SUBJECT TO CHANGE.
SUNDAY...FORECAST CONFIDENCE HIGH.
A STRONG COLD FRONT WILL DROP DOWN THROUGH WI ON SUNDAY...REACHING
SOUTHERN WI BY MID AFTERNOON. GIVEN THE STRONG DYNAMICS...OPTED TO
MENTION A SMALL CHANCE FOR SHOWERS AND MAYBE A THUNDERSTORM ALONG
THIS FRONT. IF IT HAPPENS...IT WILL BE A NARROW LINE. THE HIGHER
DEWPOINTS IN THE MID 60S WILL HANG AROUND UNTIL THE COLD FRONT DROPS
IN...SO MAX TEMPS SHOULD BE AROUND 80 WITH SOME SUNSHINE.
.SHORT TERM...SUNDAY NIGHT THROUGH TUESDAY NIGHT
SUNDAY NIGHT...FORECAST CONFIDENCE HIGH
UPPER TROUGH DIGS INTO THE UPPER GREAT LAKES REGION AS 250MB 100 KT
JET DIVES INTO...AND AROUND...THE BASE OF THE TROUGH BRINGING THE
LEADING EDGE OF THE COOLER AIR INTO THE STATE. LIGHT SHOWERS AND
POSSIBLY A THUNDERSTORM WILL EXIT THE SOUTHEAST SUNDAY EVENING WITH
THE SURFACE TROUGH/WEAK COLD FRONT. LOOKING FOR LOWS IN THE MID TO
UPPER 50S AS MAIN SHOT OF COOLER AIR STILL TO ARRIVE.
MONDAY NIGHT...FORECAST CONFIDENCE MEDIUM.
TROUGH BECOMES ELONGATED WITH A DOUBLE-BARREL STRUCTURE AS THE JET
STRENGTHENS ON THE EASTERN FLANK MONDAY/MONDAY NIGHT. LOOKING FOR
SHOWERS WITH CVA AS STRONG VORT IN SW CIRCULATION CENTER SWEEPS DOWN
THROUGH THE STATE. NAM SHOWING THE POTENTIAL FOR THUNDER WITH 150-
170 J/KG OF CAPE AND MOIST LAYER REACHING WELL ABOVE -10C...BUT GFS
SHOWING MUCH LESS CAPE AND SATURATION WELL BELOW -10C SO WILL GO
WITH SHOWERS AND LEAVE OUT MENTION OF THUNDER FOR NOW. COLD POOL
SETTLES OVER THE STATE UNDER CYCLONIC FLOW ALOFT WITH THE RESULTANT
CLOUD COVER KEEPING LOWS MONDAY NIGHT FROM FALLING BELOW THE UPPER
40S TO LOWER 50S...STILL COOL FOR THIS TIME OF YEAR.
TUESDAY AND TUESDAY NIGHT...FORECAST CONFIDENCE MEDIUM.
UPPER LOW BEGINS TO LIFT AWAY TO THE NE WITH JET MAX...WITH A
TRAILING SHORT WAVE TROUGH AND WEAK SURFACE TROUGH REFLECTION
PROVIDING CHANCES FOR RAIN SHOWERS TUESDAY. COOLEST DAY OF THE WEEK
TUESDAY IN NW FLOW...THOUGH 850 AND 925 MB HAVE TEMPERED
SOME...BRINGING HIGHS IN THE MID 60S TO UPPER 60S...OR ABOUT 10-15
DEGREES BELOW NORMAL. TROUGH SWINGS THROUGH BY TUESDAY
EVENING...WITH SLOWLY DECREASING CLOUD COVER AS HIGH PRESSURE BUILDS
IN. LOWS WILL DIP INTO THE LOWER TO MID 50S.
.LONG TERM...WEDNESDAY THROUGH SATURDAY. FORECAST CONFIDENCE
MEDIUM.
MODELS TRYING TO DEVELOP A POCKET OF LIGHT SHOWERS IN THE REGION
WEDNESDAY AFTERNOON AS WEAK...SHEARED VORT MAX SLIPS THROUGH REGION
BEFORE SHORT WAVE RIDGING BUILDS IN FOR THURSDAY. WILL LEAVE DRY FOR
NOW.
WARMER AIR BEGINS A SLOW RETURN AS UPPER FLOW BECOMES MORE
ZONAL...WITH DRY WEATHER EXPECTED THROUGH THE END OF THE WORK WEEK
INTO SATURDAY. GFS IS FASTER WITH RETURN OF MOIST WARM ADVECTION
AHEAD OF PLAINS TROUGH...BRUSHING FAR WESTERN WI WITH PCPN ON
SATURDAY AFTERNOON WITH ECMWF HOLDING OFF ON ANY PCPN UNTIL SURFACE
TROUGH MOVES IN SUNDAY AFTERNOON/EVENING.
&&
.AVIATION/00Z TAFS/...
MVFR CEILINGS MAY IMPROVE AS PERIODS OF HEAVY RAIN SPREAD INTO
SOUTHERN WI LATE THIS AFTERNOON INTO THE EARLY EVENING. BEHIND THE
RAIN...LIGHT FOG AND MVFR STRATUS WILL BE LIKELY. SKIES ARE EXPECTED
TO CLEAR SUNDAY MORNING...THEN VFR CLOUDS AND MAYBE A SHOWER OR
THUNDERSTORM IS POSSIBLE ALONG A STRONG COLD FRONT DROPPING INTO
SOUTHERN WI MID SUNDAY AFTERNOON.
THERE IS A THREAT FOR HEAVY RAIN ACROSS SOUTHERN WI BETWEEN 4 PM AND
11 PM THIS EVENING. THUNDER WILL BE ISOLATED. BEST CHANCE FOR THE
HEAVY RAIN WILL BE ALONG AND SOUTH OF THE I-94 CORRIDOR.
&&
.MARINE...
AREAS OF FOG EVIDENT VIA WEB CAMS OVER THE NEARSHORE WATERS AROUND
SHEBOYGAN THIS AFTERNOON. THIS IS DUE TO VERY MOIST AIR OVER THE
RELATIVELY COOL WATER OF LAKE MICHIGAN. FOG WILL SCOUR OUT FROM
NORTH TO SOUTH BY MIDDAY SUNDAY AS A COLD FRONT DROPS DOWN THE LAKE.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TONIGHT/SUNDAY AND AVIATION/MARINE...MRC
SUNDAY NIGHT THROUGH SATURDAY...REM
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1212 PM CDT SAT JUL 12 2014
.UPDATE...
IT IS LOOKING MORE AND MORE LIKE HEAVY RAIN ACROSS SOUTHERN WI IS
OUR MAIN THREAT FOR LATE THIS AFTERNOON/EVENING. SPC STILL HAS
SOUTHERN WI IN A SLIGHT RISK FOR SEVERE...BUT THAT IS MAINLY FOR
WIND.
THE EXTENSIVE CLOUD COVER THIS MORNING IS HELPING TO KEEP THE
SURFACE FRONT WELL TO OUR SOUTH. THE 850MB FRONT IS EXPECTED TO
SNEAK INTO SOUTH CENTRAL WI LATE THIS AFTERNOON WITH A QUICK
STRENGTHENING OF THE LOW LEVEL JET /LLJ/ AND THEN DROP SOUTHEAST
INTO NORTHERN IL THIS EVENING AS THE LLJ VEERS. FORECAST SOUNDINGS
SHOW LIMITED INSTABILITY OVER SOUTHERN WI DUE TO THE MOIST
ATMOSPHERE AND WEAK MID LEVEL LAPSE RATES...THUS SEVERE HAIL IS NO
LONGER LIKELY. THE ONLY THING LEFT FOR SEVERE POTENTIAL IS STORM
ORGANIZATION DUE TO INCREASING BULK SHEAR AND STEEP LOW LEVEL LAPSE
RATES TO ALLOW FOR STRONG THUNDERSTORM WIND GUSTS.
THERE WILL LIKELY BE A 3 TO 4 HOUR PERIOD OF MODERATE RAIN WITH
EMBEDDED AREAS OF HEAVY RAIN/THUNDERSTORMS MOVING WEST TO EAST
THROUGH SOUTHERN WI BETWEEN 5 PM AND 11 PM. THE AREA WITH GREATEST
THREAT FOR HEAVY RAIN WILL BE THE I-94 CORRIDOR AND SOUTH. INCLUDING
DELLS...MADISON AND MILWAUKEE AREAS AND SOUTH. TWO TO THREE INCHES
COULD FALL WITHIN A SHORT AMOUNT OF TIME. URBAN AREAS AND
CONSTRUCTION AREAS WILL BE SUSCEPTIBLE TO FLOODING.
WE ARE WEIGHING THE SHORT TERM PRECIP FORECAST HEAVILY ON THE HRRR
GIVEN ITS GOOD PERFORMANCE SO FAR THIS MORNING. THE HRRR AND NEW 12Z
WRF MODELS HAVE A SLIGHTLY LATER TIMING OF THE MAIN BATCH OF
THUNDERSTORMS ARRIVING IN SOUTHERN WI THAN THE RAP. THE 12Z NAM DID
NOT CAPTURE THE MORNING PRECIP VERY WELL AND SEEMS LIKE A SOUTHERN
OUTLIER AND LIGHT ON THE QPF ACROSS SOUTHERN WI...SO WILL LEAN AWAY
FROM THIS MODEL GUIDANCE TODAY. THE GFS AND CANADIAN MODELS BOTH
BULLSEYE THE PRECIP MAX OVER SOUTHERN WI EARLY THIS EVENING.
GIVEN THE SHORT NATURE OF THIS EXPECTED EVENING HEAVY RAIN EVENT...
WE ARE STILL NOT PLANNING ON ISSUING A FLASH FLOOD WATCH. SOUTHERN
WI MISSED OUT ON THE EARLY MORNING RAIN THAT HIT THE CHICAGO AREA SO
WE ARE NOT PRE-CONDITIONED FOR FLASH FLOODING. THERE IS DEFINITELY
AN URBAN FLOODING AND PONDING CONCERN...AND WE PLAN TO HANDLE THE
RAIN WITH AN URBAN AND SMALL STREAM FLOOD ADVISORY HEADLINE AT THIS
TIME. OF COURSE...THAT IS SUBJECT TO CHANGE.
&&
.AVIATION/18Z TAFS/...
INCREASING LOW LEVEL MOISTURE IS LEADING TO PATCHY MVFR CEILINGS
OVER SOUTH CENTRAL WI EARLY THIS AFTERNOON...INCLUDING KDLL AND
KMSN. THERE WILL BE BREAKS IN THE LOW CLOUDS...BUT EXPECT THE
LOWERING TREND TO CONTINUE THROUGH THE AFTERNOON ALONG AND SOUTH OF
THE I-94 CORRIDOR. THIS WILL BE THE AREA PRIMED FOR HEAVY RAIN FROM
LATE AFTERNOON THROUGH EARLY EVENING. THERE IS LESS OF A THREAT FOR
SEVERE WEATHER...BUT WITH STRONG WINDS STILL POSSIBLE. LIKELY MVFR
CIGS AND VSBYS ASSOCIATED WITH CONVECTION AND POSSIBLY BRIEFLY
LOWER.
&&
.PREV DISCUSSION... /ISSUED 330 AM CDT SAT JUL 12 2014/
TODAY...FORECAST CONFIDENCE - LOW.
WEAK WARM AIR ADVECTION FOCUSED INTO EASTERN IOWA AND NORTHERN
ILLINOIS THIS MRNG MAY CAUSE A FEW SHOWERS AND TSTORMS TO AFFECT
SOUTHERN WI...HOWEVER BETTER CHANCE FARTHER SOUTH. SEEING
CONSIDERABLE DIFFERENCES IN THE SHORT TERM GUIDANCE WITH REGARDS TO
APPROACHING SHORT WAVE AND FORCING. HENCE FORCED TO LOWER
CONFIDENCE TO LOW FOR TODAY. LEANING TOWARD MORE CONSISTENT ECMWF
IN THE SHORT TERM AS CANADIAN HAVING ISSUES WITH QPF VERIFICATION
OVERNIGHT. DO NOT CARE FOR NAM HANDLING OF UPSTREAM VIGOROUS SHORT
WAVE SO WL USE MORE OF A BLEND OF GFS AND ECMWF.
BOUNDARY LAYER MIXING AND DEEPENING LOW LEVEL MOISTURE HAVE BEEN
PRODUCING SCT-BKN STRATUS OVERNIGHT ACROSS SRN WI...HOWEVER INCREASE
IN STRATUS NOTED ON 11-3.9 MICRON IMAGERY OVER WESTERN HALF OF CWA
SINCE 05Z. INCREASE IN CLOUDS MAY ALSO BE AIDED BY WEAK LOW LEVEL
WARM AIR ADVECTION AS WELL. HENCE EXPECT CONSIDERABLE CLOUDS FOR A
TIME THIS MRNG. LOW CLOUDS WL LIKELY THIN LATER THIS MRNG AND
AFTN...BUT BY THEN MORE MID-HIGH LEVEL CLOUDS EXPECTED FROM
DEVELOPING UPSTREAM CONVECTION.
HERE ARE THE FACTORS WE ARE MORE CONFIDENT ON...PWAT VALUES LIKELY
TO INCREASE TO 1.5 TO 2 INCHES BY MID-LATE AFTN AS UPSTREAM DEWPTS
IN THE UPPER 60S TO AROUND 70 OVER SRN WI. THIS WILL REACH THE 75TH
PERCENTILE AT GRB WITH DVN HISTORICAL PWAT VALUES NEARING TWO
STANDARD DEVIATIONS FROM NORMAL. HENCE MOISTURE EXPECTED TO BE IN
PLACE. OTHER FACTOR IS THAT ALL SHORT TERM GUIDANCE IN REASONABLE
AGREEMENT ON RIGHT ENTRANCE REGION OF UPPER JET TO AFFECT SRN WI
FROM MID-AFTN INTO THE EARLY EVE. DURING THIS TIME...VIGOROUS MID-
LEVEL SHORT WAVE OVER SD/NE BORDER SHOULD BE PASSING ACROSS SRN WI
REGION. HENCE ENUF CONFIDENCE IN THESE FEATURES TO CONTINUE HIGH
MID-RANGE TO CATEGORICAL POPS LATE AFTN INTO THE EVE. THINKING BEST
THREAT WILL BE ACROSS SRN HALF OF CWA. CONSIDERED FLASH FLOOD WATCH
AS THETA-E RIDGE SPREADS ACROSS SRN CWA AROUND 00Z AND 925-850MB
MOISTURE CONVERGENCE WILL BE ALIGNED WITH 850-300MB FLOW FOR A
PERIOD. HOWEVER THESE FACTORS ONLY AFFECTING SRN WI FOR A 3-6 HOUR
PERIOD. IN ADDITION...3 HOUR FLASH FLOOD GUIDANCE ABOVE 2 INCHES
MOST AREAS AND CORFIDI VECTORS REMAIN PROGRESSIVE AND MOSTLY ABOVE
15KTS. HENCE HELD OFF ON WATCH AND WL MENTION IN HWO POTENTIAL FOR
HEAVY RAIN. WL NEED TO WATCH POTENTIAL TRAINING AFFECTING URBAN
AREAS.
TONIGHT...FORECAST CONFIDENCE - MEDIUM.
EXPECT NUMEROUS TO CATEGORICAL CONVECTION TO AFFECT SRN WI DURING
THE EVENING AS INCREASING LOW LEVEL JET BRUSHES THE AREA. BULK
SHEAR INCREASES DURING THE DAY TO 35 TO 45 KNOTS. UNSURE HOW MUCH
INSTABILITY WILL BE AVAILABLE DUE TO EXPECTED CLOUD COVER BUT CAPE
SHOULD STILL BE ABLE TO REACH 1000-2000 J. ABOUT HALF OF THE
MESOSCALE MODELS USED IN THE SPC SSEO PAINT OUT AREAS OF STRONG
UPDRAFT HELICITY AND UPDRAFT SPEED DURING THE LATE AFTN WHILE 10M
WIND SPEED NOT AS IMPRESSIVE. LOW LEVEL SHEAR APPEARS WEAK SO FOCUS
WOULD BE ON HAIL AND WINDS FROM LATE AFTN INTO THE EVENING...ALONG
WITH HEAVY RAINFALL. AS MENTIONED EARLIER...CLOUD COVER WILL BE
BIGGEST FACTOR TO SEVERE POTENTIAL.
LOW LEVEL JET PIVOTS EAST OF THE AREA LATER IN THE EVENING AS UPPER
LEVEL SHORT WAVE TRACKS OFF TO THE EAST. HENCE EXPECT CONVECTION TO
DIMINISH DURING THE EVENING IN THE WEST TO THE EAST AROUND MIDNIGHT.
WILL KEEP LINGERING SMALL POPS IN FOR AFTN MIDNIGHT IN THE EAST.
SUNDAY - CONFIDENCE...MEDIUM
WITH THE FRONT TO THE SOUTHEAST NW WINDS WILL USHER IN COOLER 850
TEMPS. THE NAM AND ECMWF ARE SHOWING A DRY SOLUTION WHILE THE GFS
HAS SHRA/ISOLD TSRA WITH A SECONDARY BOUNDARY. UPPER FLOW IS
BROADLY CYCLONIC WITH ANY VORT...MAINLY THE SHEAR/ELONGATED
VARIETY...ACROSS NORTHERN WI. WITH THE GFS BEING THE ONLY MODEL TO
GENERATE PRECIP WILL GO WI THE CONSENSUS OF MODELS AND GO WITH THE
DRY LOOK. 850 COLD ADVECTION WILL PICK UP A BIT DURING THE
AFTERNOON. HOWEVER 925 TEMPS STILL IN THE 18-20C RANGE SO HIGHS IN
THE UPPER 70S TO LOW 80S LOOK REASONABLE.
MONDAY - CONFIDENCE...MEDIUM
MORE PRONOUNCED INTRUSION OF VORTICITY AS AN UNSEASONABLY STRONG
UPPER LOW PRESSURE SYSTEM DIGS SOUTHWARD INTO THE GREAT LAKES.
DIFFERENTIAL CYCLONIC VORTICITY ADVECTION COMBINED WITH DECENT
LAPSE RATES AND SOME CAPE SHOULD RESULT IN BETTER POTENTIAL FOR
SHRA. 850 TEMPS CONTINUE TO TAKE A TUMBLE TO UNDER 10C. THE GFS
AND NAM ARE QUICKER THAN THE ECMWF ON THE COLD ADVECTION. 925
TEMPS DROP AS WELL AND SUPPORT COOL FOR JULY HIGHS IN THE MID 60S
TO LOW 70S.
TUESDAY - CONFIDENCE...MEDIUM
UPPER LOW SHIFTS EAST WITH THE GEM AND ECMWF SOLUTIONS SLOWER ON
THE PROGRESS AND THE NAM/GFS MUCH MORE PROGRESSIVE. THE ECMWF
SHOWS AN 850 TEMP JUST A SMIDGE UNDER 3C AT 12Z ACROSS SC WI. IN
EITHER CASE EXPECT A STRONGLY CYCLONIC FLOW TO KEEP SHRA CHANCES
GOING WITHIN THIS VERY COOL AIRMASS. 925 TEMPS ONLY MODIFY TO
10-13C IN THE AFTN HRS...WHICH TRANSLATES TO HIGHS FOR MOST NOT
GETTING OUT OF THE MID 60S. TAKING A COMPROMISE APPROACH WITH THE
925 TEMPS...WITH A NOD TO THE SOMEWHAT COOLER ECMWF SHOWS HIGHS
FOR MOST AREAS NOT GETTING OUT OF THE MID 60S.
WEDNESDAY - CONFIDENCE...MEDIUM
UPPER FLOW STILL SHOWING A CYCLONIC CURVATURE THOUGH SURFACE HIGH
DRAWS CLOSER AND AIRMASS DRIES OUT. MAY NEED A SMALL CHANCE OR
SPRINKLES ESP IN ERN AND NE CWA AS WE GET CLOSER BUT FOR NOW WILL
GO WITH THE DRY COLLAB WITH SURROUNDING OFFICES.
THURSDAY AND FRIDAY - CONFIDENCE...MEDIUM
FAIRLY BENIGN NW FLOW. CHILLY TEMPS SLOWLY MODIFY. NOT READY TO
BUY INTO THE LIGHT...SPOTTY AND RANDOM NATURE OF QPF BEING THROWN
AROUND BY THE MODELS WITH LOW LEVEL ANTICYCLONIC FLOW AND ANY
WAVES QUITE WEAK. SO WILL STICK WITH THE DRY POPS AT THIS POINT.
AVIATION/12Z TAFS/...STRATUS LOWERING TO MVFR WEST OF MADISON LAST
SEVERAL HOURS. EXPECT THIS TREND TO CONTINUE TO THE EAST SO FOR NOW
WL CONTINUE A PERIOD OF LOWER MVFR CIGS RISING TO VFR LATER THIS MRNG.
HIGH HUMIDITY AND DEWPTS RETURNING TODAY HELPING TO FUEL SCT TO NUMEROUS
CONVECTION FROM MID-AFTN THROUGH THE EVENING. LIKELY MVFR CIGS AND
VSBYS ASSOCD WITH CONVECTION AND POSSIBLY BRIEFLY LOWER. MOST FAVORABLE
TIMES FOR CONVECTION WL BE LISTED IN TAFS.
MARINE...PATCHY OVERNIGHT CLEARING HAS ALLOWED THE MODIS IMAGER TO
CATCH SOME SEA SURFACE TEMPERATURE MEASUREMENTS FROM THE NEARSHORE
WATERS OF LAKE MI. TEMPERATURES IN THE 50S...WITH THE COOLEST
READINGS NORTH OF NORTH POINT LIGHT TO SHEBOYGAN. WITH SFC
DEWPOINTS EXPECTED TO APPROACH 70 LATER TODAY AND TONIGHT...WOULD
EXPECT AT LEAST PATCHY FOG OVER THE NEARSHORE WATERS TO DEVELOP.
WILL HOLD OFF ON GOING MORE WIDESPREAD OR DENSE ATTM DUE TO SHOWERS
AND TSTORMS EXPECTED TO AFFECT THE NEAR SHORE WATERS TONIGHT. WILL
MENTION THREAT IN HAZARDOUS WX OUTLOOK.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...MRC
TODAY/TONIGHT AND AVIATION/MARINE...MBK
SUNDAY THROUGH FRIDAY...COLLAR
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1145 AM CDT SAT JUL 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 319 AM CDT SAT JUL 12 2014
MAIN SHORT TERM CONCERN IS ON PRECIPITATION TRENDS THROUGH THE
EVENING AS WELL AS SEVERE WEATHER POTENTIAL.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A SUBTROPICAL HIGH OVER THE CENTRAL PLAINS AND A DEEP UPPER
TROUGHING COVERING MUCH OF CENTRAL CANADA. A SERIES OF MONSOONAL
SHORTWAVES WERE COMING AROUND THE WEST SIDE OF THE SUBTROPICAL
HIGH...ONE OVER SOUTH CENTRAL SOUTH DAKOTA AND A SECOND IN WYOMING. A
STREAM OF TROPICAL PACIFIC MOISTURE WAS ALSO EVIDENT AROUND THE
SUBTROPICAL HIGH. IN THE LOWER LEVELS...A PLUME OF 15-18C 850MB
DEWPOINTS STRETCHED FROM OKLAHOMA INTO SOUTH DAKOTA AND SOUTHERN
MINNESOTA PER 00Z RAOBS. ALL THIS MOISTURE EQUATES TO PRECIPITABLE
WATER VALUES OF AROUND 2 INCHES FROM SIOUX FALLS AREA SOUTHEAST INTO
CENTRAL ILLINOIS. A ZONE OF 850MB MOISTURE TRANSPORT AHEAD OF THE
MONSOONAL SHORTWAVES ACTING ON THIS MOISTURE...ALONG WITH LOW TO MID
LEVEL FRONTOGENESIS...HAS LED TO SHOWERS AND STORMS IN THAT
PRECIPITABLE WATER MAXIMUM. THIS PRECIPITATION HAS CAUSED THE
MAIN SURFACE WARM FRONT TO GET STUCK IN FAR SOUTHERN IOWA.
SOME OF THE GENERALITIES FOR TODAYS FORECAST. THE 2 MONSOONAL
SHORTWAVES WILL TRACK ACROSS THE FORECAST AREA...HELPING TO PULL THE
850MB MOISTURE TRANSPORT ZONE AND LOW TO MID LEVEL FRONTOGENESIS
NORTHWARD TOWARDS AND POSSIBLY INTO THE AREA. IN ADDITION...AN UPPER
JET STREAK ASSOCIATED WITH THE CENTRAL CANADA UPPER TROUGH IS
PROGGED TO ALIGN ITSELF FROM CENTRAL MN THROUGH LAKE SUPERIOR...
PLACING SOME IF NOT ALL OF THE FORECAST AREA IN THE FAVORABLE RIGHT
ENTRANCE REGION. INSTABILITY WISE...ALONG AND SOUTH OF THE WARM
FRONTAL BOUNDARY 1500-2500 J/KG OF MLCAPE SEEMS REASONABLE TO
DEVELOP THIS AFTERNOON...AS TEMPS CLIMB INTO THE 80S AND DEWPOINTS
HOVER IN THE MID 70S OR SO. PLENTIFUL PRECIPITABLE WATER AROUND AS
WELL AS NOTED IN THE CURRENT WEATHER DISCUSSION...RUNNING AROUND 2
INCHES. THUS...PLENTY OF MOISTURE EXISTS TO COMBINE WITH DYNAMIC AND
THERMODYNAMIC FORCING TO PRODUCE CONVECTION. 0-6KM AND 0-3KM SHEAR
VALUES REMAIN FAVORABLE FOR ORGANIZED SEVERE CONVECTION...ON THE
ORDER OF 40-50 KT AND 30-45 KT RESPECTIVELY. MUCH OF THIS SHEAR IS
CONFINED ABOVE 1 KM AS THE WINDS BELOW ARE FAIRLY LIGHT. STILL HAVE
CYCLONIC CURVATURE IN THE HODOGRAPH...THOUGH. BASED ON THE
AFOREMENTIONED PARAMETERS...DAMAGING WINDS AND HEAVY RAINS WOULD BE
THE MAIN CONCERNS...WITH SOME MARGINALLY SEVERE HAIL AND AN OUTSIDE
CHANCE OF A TORNADO. THE HIGHER SHEAR AND DRYING SOILS AS OF LATE
SHOULD HELP TO KEEP ANY FLOOD CONCERN LOCALIZED...IN AGREEMENT TOO
WITH THE DAY 1 EXCESSIVE RAINFALL OUTLOOK.
NOW...THE CRITICAL UNCERTAINTIES...
1. TIMING AND INTENSITY OF THE 2 MONSOONAL SHORTWAVES...WHICH
IMPACTS THE MOVEMENT OF THE 850MB MOISTURE TRANSPORT ZONE AND LOW TO
MID LEVEL FRONTOGENESIS. WHERE THAT MOISTURE TRANSPORT NOSE...F-GEN
ZONE...AND DPVA FROM THE SHORTWAVES WILL MODULATE WHERE THE
CONVECTION ENDS UP. MODELS ARE ALL OVER THE BOARD WITH THESE
SHORTWAVES...LEADING TO LOWERED CONFIDENCE.
2. HOW FAR NORTH THE WARM FRONT CAN MAKE IT WHICH IMPACTS THE ZONE
OF INSTABILITY AND THUS HOW FAR NORTH THROUGH THE FORECAST AREA A
SEVERE RISK EXISTS. ITEM NUMBER 1 ABOVE WILL IMPACT THE WARM FRONT.
DESPITE THE UNCERTAINTIES ABOVE...IT STILL APPEARS THROUGH THIS
EVENING LOCATIONS SOUTH OF I-90 STAND TO SEE THE HIGHEST CHANCE FOR
CONVECTION. ADDITIONALLY...SEVERE WEATHER IS GOING TO HAPPEN BETWEEN
I-80 AND I-90 AFTER 2 PM TODAY...CONSISTING OF SUPERCELLS AND BOW
SEGMENTS. PINNING DOWN THE LOCATION ANY FINER THAN THAT IS
PROBLEMATIC AT THIS TIME. LATER FORECAST UPDATES SHOULD BE ABLE TO
REFINE THE LOCATION AND TIMING.
HAVE ADJUSTED THE MORNING PORTION OF THE FORECAST TO FOLLOW TRENDS
IN THE HRRR...WHILE A MODEL CONSENSUS DOMINATES THE AFTERNOON AND
EVENING. NOTE THAT THERE COULD ALSO BE SOME SURFACE BASED CONVECTION
THAT FIRES OVER WEST CENTRAL WI THIS AFTERNOON ALONG A SOUTHEASTWARD
MOVING COLD FRONT. THE AFOREMENTIONED CONSENSUS JUST HAPPENS TO BE
SIMILAR TO THE 00Z NSSL WRF-ARW. HEADING INTO TONIGHT...THERE WILL
BE A NORTHWEST TO SOUTHEAST DRYING TREND AS THE SHORTWAVES PUSH OFF
TO THE EAST... USHERING IN SUBSIDENCE AND MUCH DRIER PRECIPITABLE
WATER VALUES.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 319 AM CDT SAT JUL 12 2014
A GRADUAL DESCENT OF THE DEEP UPPER TROUGH OVER CENTRAL CANADA INTO
THE FORECAST AREA REMAINS ON TRACK BETWEEN SUNDAY AND MONDAY...WITH
THE TROUGH SLOWLY PUSHING TO THE EAST ON TUESDAY. AS THIS
OCCURS...THERE ARE COUPLE OF ISSUES TO CONTEND WITH...
1. POTENTIAL FOR CONVECTION ON SUNDAY. A SURFACE COLD FRONT IS
PROGGED TO DROP THROUGH THE AREA...THOUGH THERE DOES NOT APPEAR TO
BE MUCH CONVERGENCE ON IT. THE 12.00Z ECMWF/NAM/REGIONAL
CANADIAN/HIRES ARW AND NMM ARE DRY...WHILE THE 12.00Z GFS HAS
REDUCED ITS QPF EVEN MORE. THE GFS STILL HAS TOO HIGH SURFACE
DEWPOINTS IN WHAT SHOULD BE A FAVORABLE MIXING REGIME...THUS PREFER
THE DRIER IDEA.
2. RAIN CHANCES MONDAY THROUGH TUESDAY. AN UPPER LOW WITHIN THE
TROUGH WILL SLIDE ACROSS NORTHERN WI MONDAY EVENING. DPVA FORCING
AHEAD OF THE UPPER LOW AND DAYTIME INSTABILITY SHOULD PROMOTE PLENTY
OF SHOWER ACTIVITY...ESPECIALLY ALONG AND NORTH OF HIGHWAY 29 CLOSER
TO THE UPPER LOW. SOME SHOWER ACTIVITY COULD CONTINUE INTO
TUESDAY...MAINLY IN WISCONSIN CLOSER TO THE UPPER TROUGH AXIS.
3. TEMPERATURES MONDAY AND TUESDAY. 850MB TEMP ANOMALIES PLUMMET TO
2 TO 2.5 STANDARD DEVIATIONS BELOW NORMAL DURING THIS PERIOD...OR
GENERALLY IN THE 4-7C RANGE. THESE READINGS GENERALLY SUPPORT HIGHS
IN THE 60S. HOWEVER...THERE ARE SOME MODEL SUGGESTIONS ON TUESDAY
THAT...DEPENDING ON HOW QUICK THE TROUGH PUSHES EAST...BOTH THE
850MB TEMP AND ACTUAL HIGH COULD BE A LITTLE WARMER. LOWS WILL BE
HELD UP SOMEWHAT BY BOTH CLOUDS AND A NORTHWESTERLY BREEZE. NEEDLESS
TO SAY...ITS GOING TO FEEL MORE LIKE FALL VERSUS SUMMER.
AFTER TUESDAY AND THROUGH THE END OF THE WEEK...EXPECT A LONG DRY
PERIOD AS SURFACE HIGH PRESSURE DOMINATES AND 500MB HEIGHTS RISE.
HOWEVER...THE 12.00Z GFS SHOWS DIURNALLY DRIVEN WIDESPREAD LIGHT
PRECIP WEDNESDAY...THURSDAY AND FRIDAY. THE MODEL APPEARS TO BE
SUFFERING FROM OVER-DOING EVAPOTRANSPIRATION...NOTED IN ITS SURFACE
DEWPOINT FIELD...AND THUS CONVECTS EASIER. THUS...HAVE IGNORED IT
AND STAYED WITH THE DRY ECMWF/CANADIAN.
TEMPERATURES WILL GRADUALLY WARM THROUGH THE WEEK...GETTING CLOSE TO
NORMAL FOR THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY EVENING)
ISSUED AT 1145 AM CDT SAT JUL 11 2014
UPPER LEVEL SHORTWAVE...MID LEVEL WARM AIR ADVECTION/FRONTOGENETIC
LIFT ALL HAVING A PART IN PERSISTENT RAIN ACROSS MUCH OF MN LATE
THIS MORNING. THE -SHRA WAS PUSHING EAST...MOSTLY OUT OF MID
LEVEL/VFR CLOUDS. EXPECT THIS TO PERSIST THROUGH MUCH OF THE
AFTERNOON. SOME THREAT FOR -TSRA...BUT THE BEST INSTABILITY HOLDS
WELL SOUTH. FEEL THE CHANCES ARE MORE OF THE ISOLD/SCT VARIETY...AND
WILL LEAVE OUT OF THE TAFS FOR NOW. IF RADAR/MESO MODEL TRENDS START
TO FAVOR KRST/KLSE BEING IMPACTED BY A TS...WITH UPDATE FORECAST TO
REFLECT. WILL ALSO KEEP CIGS VFR FOR NOW...WITH THE CAVEAT OF MVFR
CONDITIONS IF THUNDERSTORMS BECOME MORE LIKELY. THE 5SM -SHRA/BR
SEEMS LIKELY FOR KRST THROUGH THE AFTERNOON.
EXPECT THE PCPN CHANCES TO CLEAR EAST NEAR 00Z THIS EVENING...WITH A
CLEARING TREND FOR THE OVERNIGHT HOURS. COULD HAVE SOME MVFR
BR...AND WILL SOME IN FOR KRST.
&&
.HYDROLOGY...
ISSUED AT 319 AM CDT SAT JUL 12 2014
THERE IS A CONCERN FOR FLASH FLOODING THIS AFTERNOON INTO THIS
EVENING...PRIMARILY ACROSS NORTHEAST IOWA AND FAR SOUTHWEST
WISCONSIN. STORMS IN THIS REGION WILL BE CAPABLE OF PRODUCING VERY
HEAVY RAIN DUE TO A NEARLY TROPICAL AIRMASS IN PLACE. NO FLASH
FLOOD WATCH IS BEING ISSUED AT THIS TIME...THOUGH...BECAUSE OF
1. STRONG 0-3/0-6KM SHEAR WHICH SHOULD KEEP STORMS PROGRESSIVE
2. ANTECEDENT CONDITIONS HAVE DRIED OUT AND CAN TAKE MORE WATER
NEVERTHELESS...SINCE STORMS WILL HAVE HIGH RAINFALL RATES...THERE
COULD BE A NEED FOR A FLASH FLOOD WARNING OR TWO.
&&
.CLIMATE...
ISSUED AT 319 AM CDT SAT JUL 12 2014
RECORD COOL HIGH TEMPERATURES ARE POSSIBLE MONDAY AND TUESDAY AS AN
UNSEASONABLY COLD AIRMASS SETTLES OVER THE UPPER MISSISSIPPI RIVER
VALLEY.
FOR LA CROSSE...
MONDAY....FORECAST HIGH 69. RECORD 65 IN 1994
TUESDAY...FORECAST HIGH 68. RECORD 68 IN 1962
FOR ROCHESTER...
MONDAY....FORECAST HIGH 64. RECORD 64 IN 1952
TUESDAY...FORECAST HIGH 67. RECORD 67 IN 1962
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....RIECK
HYDROLOGY....AJ
CLIMATE......AJ