Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/16/13
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
931 AM MST SUN JUL 14 2013
.SYNOPSIS...
A DEEP MONSOON AIRMASS WILL REMAIN OVER THE EASTERN PORTION OF THE
REGION THIS WEEK. THE THREAT OF AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS WILL CONTINUE...MAINLY OVER THE CENTRAL AND EASTERN
ARIZONA MOUNTAINS. AFTERNOON TEMPERATURES NEAR OR SLIGHTLY ABOVE
NORMAL ARE EXPECTED THROUGH MONDAY AND THEN COOLING CONSIDERABLY BY
THE MIDDLE PART OF THE WEEK. MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE ACROSS SOUTHERN ARIZONA STARTING
TUESDAY.
&&
.DISCUSSION...
12Z SOUNDING FROM PHOENIX INDICATED APPROXIMATELY 500 J/KG CAPE
ABOVE 700MB THIS MORNING...SURE ENOUGH THERE WERE A FEW ELEVATED
SHOWERS AND THUNDERSTORMS ACROSS THE AREA EARLIER TODAY /MAINLY
ACROSS SW AZ AND SE CA/. MOST OF THIS ACTIVITY HAS SINCE DISSIPATED
WITH LITTLE PRECIP LEFT ON THE RADAR AS OF 16Z. LINGERING CLOUD
COVER FROM THESE STORMS SURE TOOK AWAY SEVERAL HOURS OF GOOD
RADIATIONAL COOLING...MOST DESERT LOCATIONS ONLY DROPPED INTO THE
UPPER 80S/LOWER 90S THIS MORNING. NEEDLESS TO SAY...IT WAS A WARM
START TO THE MORNING.
FORECAST FOR LATER TODAY REMAINS LARGELY UNCHANGED...AS ALL HI-RES
MODELS AND LATEST HRRR MODEL INDICATE STORMS SHOULD BE CONFINED TO
THE RIM AND POINTS EAST OF PHOENIX. CURRENT FORECAST ONLY CALLS FOR
AN ISOLATED SHOWER OR THUNDERSTORM ACROSS THE DESERTS AND THIS STILL
SEEMS APPROPRIATE GIVEN 12Z MODEL DATA. HIGHER POPS /AROUND 30
PERCENT/ WILL REMAIN IN PLACE EAST OF PHOENIX...NO REAL CHANGES
NECESSARY.
MADE MINOR ADJUSTMENTS TO MAX TEMPS BASED ON TRENDS THROUGH 16Z.
GIVEN THE WARM START...I ADDED 1-2 DEGREES TO THE HIGHS ACROSS MOST
OF THE FORECAST AREA. ALREADY PUSHING 98 AT KPHX...HIGHS 105-110
SEEM REASONABLE GIVEN THE WARM START AND SLIGHTLY LOWER DEWPOINTS
THAN THIS TIME SATURDAY.
&&
.PREVIOUS DISCUSSION...
EVEN SMALLER CHANCES FOR MONSOON STORMS ARE EXPECTED FOR MONDAY AS
THE FULL EXTENT OF THE QUASI DRY AIR IS FELT. ALL STORMS SHOULD BE
CONFINED TO THE HIGHER TERRAIN NORTH AND EAST OF PHOENIX. ALTHOUGH
MONDAY WILL BE FAIRLY QUIET...THE RETROGRADING UPPER LOW FROM THE
OHIO RIVER VALLEY WILL BE NEARING THE DESERT SOUTHWEST. ALL
OPERATIONAL MODELS AND ENSEMBLES INDICATE IT WILL MOVE INTO NEW
MEXICO AND ARIZONA BY MONDAY NIGHT INTO TUESDAY. HARD TO IMAGINE AN
UPPER LOW RETROGRADING TO THAT DEGREE...BUT ITS BEEN ADVERTISED FOR
SEVERAL DAYS NOW AND WV IMAGERY CLEARLY DEPICTING THE SOUTHWESTERLY
MOVEMENT OF THE LOW.
THE UPPER LOW WILL USHER IN EVEN HIGHER MIXING RATIOS MONDAY INTO
TUESDAY. SOME OF OUR BIGGEST CONVECTIVE EVENTS CLIMATOLOGICALLY HAVE
BEEN EASTERLY WAVES COMING IN FROM THE FOUR CORNERS. CHANCE POPS FOR
MONDAY AND MONDAY NIGHT EAST OF PHOENIX STILL SEEMS REASONABLE WITH
CHANCE POPS TUESDAY ACROSS THE METRO PHOENIX AREA AND LIKELY POPS TO
THE EAST. THERE ARE STILL SOME MODEL DIFFERENCES IN THE TRACK AND
THE POSITIONING OF THE LOW AS IT NEARS AND MOVES THROUGH THE AREA SO
IT IS TOUGH TO SAY WHICH DAY WILL BE THE BUSIEST WEATHER DAY THIS
WEEK. TEMPERATURE FORECAST IS ALSO ON THE DIFFICULT SIDE WITH A
LARGE DISTRIBUTION OF TEMPERATURES AMONG GUIDANCE. HAVE TRENDED
COOLER FROM PHOENIX EASTWARD TUESDAY THROUGH THE END OF THE WEEK. IT
IS CONCEIVABLE WE COULD HAVE A DAY SOMEWHERE IN THE TUESDAY TO
FRIDAY TIME FRAME WHERE HIGHS DON/T MAKE IT ABOVE 90 IN SOME LOWER
DESERT LOCATIONS. THE QUESTION OF HOW LONG THE LOW WILL REMAIN OVER
THE AREA WILL DETERMINE RAIN CHANCES AND TEMPERATURES AFTER
WEDNESDAY. AT THIS POINT...IT IS TOO EARLY TO TELL HOW LONG THIS LOW
WILL END UP INFLUENCING OUR WEATHER IN THE COMING WEEK.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX...KIWA AND KSDL...
ONLY PERIODIC HIGH/MID CLOUDS ARE EXPECTED TO SPREAD OVER CNTRL
ARIZONA TERMINALS THROUGH MONDAY MORNING. SHRA/TSRA SHOULD REMAIN
WELL TO THE NORTH AND EAST OF THE PHOENIX AREA...WITH LITTLE CHANCE
OF ANY OUTFLOWS REACHING THE SITES. OTHERWISE...LARGELY LIGHT AND
VARIABLE WINDS SHOULD BECOME PREDOMINATELY W/SW BY LATE
MORNING...AND LIKELY PERSISTING AS SUCH WELL INTO THE EVENING HOURS.
SOUTHEAST CA AND SOUTHWEST AZ...INCLUDING KIPL AND KBLH...
MID/HIGH CLOUDS WILL PERIODICALLY COVER SERN CALIFORNIA
TERMINALS...WITH NO STORM ACTIVITY OR IMPACTS EXPECTED. WINDS WILL
GENERALLY REMAIN BELOW 10 KT AND RETAIN A BASE SOUTHERLY COMPONENT
THROUGH MONDAY MORNING.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH FRIDAY...
A SEASONABLY STRONG UPPER LOW WILL BE MOVE INTO THE REGION FROM THE
EAST...AND BECOME THE TRIGGER FOR AN ACTIVE PERIOD OF SHOWERS AND
THUNDERSTORMS. MOST LOCATIONS IN ARIZONA WILL EXPERIENCE A GOOD
CHANCE FOR WETTING RAINS...WITH SOMEWHAT LESSER CHANCES OVER
SOUTHEAST CALIFORNIA. MINIMUM HUMIDITIES WILL BE HIGHER THAN
NORMAL...IN THE 20-30 RANGE ACROSS THE LOWER DESERTS...AND 40
PERCENT OR HIGHER OVER THE HIGHER TERRAIN...WITH EXCELLENT OVERNIGHT
RECOVERY. WINDS WILL OBTAIN MORE OF A PERSISTENT EASTERLY DIRECTION
THROUGH MUCH OF THE PERIOD...WITH OCCASIONAL LOCALLY HIGHER GUSTS IN
ASSOCIATION WITH THUNDERSTORM OUTFLOW BOUNDARIES.
&&
$$
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...LEINS/KUHLMAN
AVIATION...MO
FIRE WEATHER...MO/PERCHA
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1055 AM EDT SUN JUL 14 2013
.SYNOPSIS...
HIGH PRESSURE REMAINS OVER THE REGION THROUGH THE MIDDLE OF THE
WEEK WITH A FEW TROUGHS OF LOW PRESSURE NEARBY. A COLD FRONT THEN
SLOWLY APPROACHES FROM THE NORTH LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WITH WESTERLY WINDS INCREASING...THE FOG AND LOW CLOUDS CONTINUES
TO DISSIPATE.
MADE NO CHANGES TO TEMP FORECAST AS SKIES WILL BE PARTLY TO
MOSTLY SUNNY THIS AFTERNOON. ALONG WITH A WESTERLY WIND...MIXING
PROFILES SUPPORT HIGHS IN THE LOW 90S FOR PARTS OF NE NJ...AND
AROUND 90 FOR ADJACENT AREAS. UPPER 80S EXPECTED ELSEWHERE.
DEW POINTS ALOFT ARE ON THE HIGH SIDE...AND WILL COUNTERACT THE
SURFACE WESTERLY WINDS IN LOWERING SURFACE DEW POINTS. THINKING IS
THAT SURFACE DEW POINTS OUTSIDE OF SEA BREEZE INFLUENCES DROP ONLY
A COUPLE OF DEGREES FROM 12Z READINGS. THIS PRODUCES HEAT INDICES
MEETING HEAT ADVISORY CRITERIA NYC AND PARTS OF NE NJ. AS
SUCH...THE HEAT ADVISORY WILL REMAIN POSTED AS IS.
MID-LEVEL SHORTWAVE APPROACHES THIS AFTERNOON AS WELL. SOME
QUESTIONS AS TO WHERE IT WILL TRACK...BUT NAM AND HRRR INDICATING
CONVECTION A BIT FARTHER TO THE WEST...WILL INCREASE POPS TO
CHANCE ACROSS AREAS NORTH AND WEST OF THE CITY AND WILL KEEP
SLIGHT CHANCE POPS THROUGHOUT. WITH SFC DEW POINTS IN THE LOW 70S
AND PWATS APPROACHING 2 INCHES...WILL MENTION POTENTIAL FOR HEAVY
RAIN IN TSTMS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
DRY WEATHER TONIGHT THROUGH TUESDAY NIGHT AS THE ATMOSPHERIC COLUMN
DRIES OUT.
ON MONDAY...850MB TEMPS RISE TO 18-19C...AND WITH A MOSTLY SUNNY
AFTERNOON...EXPECTING HIGHS IN THE LOWER AND MIDDLE 90S FOR MUCH OF
THE FORECAST AREA. WINDS IN THE MIXING LAYER...ALTHOUGH WITH AN
OFFSHORE COMPONENT...LOOK LIGHT ENOUGH TO ALLOW FOR SEA BREEZES TO
DEVELOP IN THE AFTERNOON...AND COMPLICATE THE SURFACE DEW POINT
FORECAST. DEW POINTS IN THE BOUNDARY LAYER ARE FORECAST TO BE LOW
ENOUGH TO ALLOW SURFACE DEW POINTS TO DROP AT LEAST 3-5 DEGREES FROM
12Z READINGS. BUT WITH AMBIENT TEMPERATURES IN THE MID 90S IN THE
CITY...WIDESPREAD HEAT INDEX VALUES OF 95-100 SHOULD BE REALIZED.
OUTSIDE OF THE CITY...100-104 DEGREE HEAT INDICES WILL BE WIDESPREAD
ACROSS PARTS OF NJ WHERE THE HEAT ADVISORY IS CURRENTLY IN EFFECT.
MIGHT NEED TO EVENTUALLY ADD ADJACENT ZONES TO THE ADVISORY...BUT AS
OF NOW...WIDESPREAD 100-104 INDICES ARE NOT FORECAST.
THERMAL TROUGH DEVELOPS IN THE AFTERNOON OVER WESTERN ZONES...AND
ANOTHER TROUGH APPROACHES FROM THE EAST. COMBINED WITH ANY LOCAL
SEA BREEZES...WILL GO AHEAD AND ADD ISOLATED POPS TO THE FORECAST
FOR THE AFTERNOON.
MODELS DIVERGE ON THE 850MB TEMPERATURE FORECAST FOR TUESDAY...BUT
BEST GUESS IS THAT THEY WILL BE THE SAME OR JUST SLIGHTLY LOWER THAN
ON MONDAY. EVEN IF THEY ARE LOWER...SURFACE HIGH TEMPERATURES WILL
PROBABLY BE VERY CLOSE TO THOSE OF MONDAY AS THE MIXED LAYER WILL BE
DRIER THIS TIME AROUND. THIS WILL ALSO SERVE TO ALLOW SURFACE
DEW POINTS TO MIX OUT MORE THAN ON MONDAY. THE RESULTING HEAT INDICES
WOULD STILL WARRANT A HEAT ADVISORY TO BE EXTENDED IN THE CITY...BUT
FALLING SHORT OF CRITERIA ELSEWHERE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
HEAT AND HUMIDITY CONTINUES THROUGH THE WEEK WITH ADDITIONAL HEAT
ADVSYS POSSIBLE...ESPECIALLY IN NYC. FORECASTING HEAT INDICES
BECOMES TROUBLESOME DUE TO THE POTENTIAL FOR THE MIXING DOWN OF
DRIER AIR FROM ALOFT EACH AFTERNOON. WILL NEED TO MONITOR TRENDS
CLOSELY IN THE COMING DAYS.
IN ADDITION TO THE HEAT...A TROUGH OF LOW PRES WILL BE NEAR OR OVER
THE AREA EACH DAY WITH THE POTENTIAL FOR DIURNALLY DRIVEN ISOLD
SHOWERS/TSTMS. PREDICTABILITY IS TOO LOW TO PINPOINT WHERE EXACTLY
THESE WILL OCCUR...HOWEVER ANY WEAK BOUNDARY OR CONVERGENCE ZONE
WILL BE CAPABLE OF TRIGGERING CONVECTION.
TOWARDS THE END OF THE FORECAST PERIOD A COLD FRONT WILL SLOWLY DROP
DOWN FROM THE N BRINGING THE POTENTIAL FOR MORE ORGANIZED PRECIP.
THE FRONT IS EXPECTED TO BECOME ALIGNED WITH THE FLOW ALOFT
RESULTING IN A SLOW PROGRESSION SOUTHWARD. THE DEGREE OF THIS VARIES
AMONGST THE MODEL GUIDANCE WHICH IS LEADING TO LARGE TIMING
DISCREPANCIES. HOWEVER...IT APPEARS THAT IT WILL COME THROUGH
SOMETIME NEXT WEEKEND.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE OVER THE AREA WILL MOVE SLOWLY WEST THROUGH MONDAY.
WEAK TROUGHS OF LOW PRESSURE EXTENDING FROM SOUTHWEST TO NORTHEAST
JUST WEST OF THE LOCAL AREA WILL FORM SUNDAY AND MONDAY AFTERNOONS.
ISOLATED MVFR CIGS ARE POSSIBLE ACROSS THE LOCAL AREA UNTIL 16Z.
ISOLATED SHOWERS DEVELOPING OVER CT MIGHT EXPAND WEST ACROSS THE
HUDSON VALLEY AS THEY MOVE SLOWLY SOUTHEAST. FCST CONFIDENCE IS TOO
LOW TO INCLUDE IN THE TAF FORECASTS.
WINDS WILL BE WEST ARND 10 KT UNTIL 19Z WITH WEAK SEA BREEZES
DEVELOPING ACROSS THE COASTAL TERMINALS.
PATCHY MVFR FOG IS POSSIBLE AFT 06Z TONIGHT OUTSIDE OF THE NYC METRO
TERMINALS.
.OUTLOOK FOR 12Z MONDAY THROUGH THURSDAY...
.MONDAY THROUGH THURSDAY...MAINLY VFR...BUT SUB-VFR CONDS POSSIBLE
IN SHRA/TSRA NORTH AND WEST OF NYC DURING THE AFTERNOON/EVENING
HOURS.
&&
.MARINE...
HIGH PRESSURE BUILDS OVER THE WATERS AND WILL REMAIN THROUGH THE
FORECAST PERIOD.
CONDITIONS ARE FORECAST TO REMAIN BELOW SMALL CRAFT ADVISORY LEVELS
THROUGH THURSDAY. NO HAZARDS ARE EXPECTED OTHER THAN POSSIBLY FOR
FOG THROUGH THE REMAINDER OF THE PERIOD WITH A RELATIVELY WEAK FLOW
OVER THE WATERS.
&&
.HYDROLOGY...
A MOIST AIR MASS OVER THE AREA WILL RESULT IN THE POTENTIAL FOR
HEAVY DOWNPOURS ASSOCIATED WITH ANY TSTM ACTIVITY TODAY INTO THE
EVENING. PWATS AROUND 2 INCHES ASSOCIATED WITH ANY SLOW MOVING STORM
WILL HAVE THE CAPABILITY TO PRODUCE FLASH FLOODING...ALTHOUGH
CONFIDENCE IS LOW AT THIS TIME.
MONDAY AND TUESDAY LIKELY REMAIN DRY. THEREAFTER...STORMS ARE
EXPECTED TO BE ISOLD IN NATURE THROUGH AT LEAST THURSDAY...LIMITING
THE POTENTIAL FOR WIDESPREAD FLASH FLOODING.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...HEAT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR NYZ072>075-
176-178.
NJ...HEAT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR NJZ006-104-
106-108.
MARINE...NONE.
&&
$$
SYNOPSIS...JC
NEAR TERM...JC/MPS
SHORT TERM...JC/MPS
LONG TERM...
AVIATION...MET
MARINE...MET
HYDROLOGY...JC
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
933 PM EDT MON JUL 15 2013
.SYNOPSIS...
AN OPPRESSIVE HIGH PRESSURE SYSTEM ALONG THE EASTERN SEABOARD IS
EXPECTED TO REMAIN NEARLY STATIONARY THROUGH FRIDAY. A SLOWLY
SOUTHWARD SAGGING COLD FRONT IS FORECAST TO REACH THE NORTHERN
GREAT LAKES ON THURSDAY, LAKE ONTARIO AND LAKE ERIE ON FRIDAY AND
THEN MOVE INTO OUR AREA ON SATURDAY. A SECOND COLD FRONT FROM
EASTERN CANADA IS THEN EXPECTED TO MOVE THROUGH OUR REGION LATER
SUNDAY INTO MONDAY.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
THE EXCESSIVE HEAT WARNING REMAINS IN EFFECT.
THE CAP WAS ABLE TO BE BROKEN ENOUGH LATE THIS AFTERNOON TO ALLOW
FOR A FEW SHOWERS AND THUNDERSTORMS TO DEVELOP. THESE WERE MAINLY
TRIGGERED BY A WEAK WIND SHIFT/THERMAL TROUGH. THE MODEL GUIDANCE
INDICATES A SUBTLE SHORT WAVE ROUNDING THE EASTERN SIDE OF THE
RIDGE OVERNIGHT. THERE DOES NOT APPEAR TO BE ANY APPRECIABLE
FORCING TIED TO IT, THEREFORE TIME MAY BE RUNNING OUT FOR ANY
ADDITIONAL DEVELOPMENT. WHILE THE HRRR HAS BEEN OVERDONE WITH
COVERAGE THUS FAR, IT AND THE SPC WRF PRETTY MUCH INSIST THAT SOME
NEW DEVELOPMENT OCCURS MAINLY IN THE DELMARVA FOR A TIME TONIGHT.
THE NAM HAS BEEN SHOWING THIS AS WELL. WHILE OUR CONFIDENCE IS ON
THE LOWER SIDE STILL, WE MAINTAINED A SLIGHT CHC POP BUT CONFINED
THIS TO PORTIONS OF THE DELMARVA /CLOSET TO THE FORECAST SHORT
WAVE/ AND LIMITED IT TO JUST A SHOWER MENTION.
THE FLOW IS RATHER LIGHT AND WITH THE LOSS OF DAYTIME HEATING,
MANY LOCALES HAVE A CALM WIND. THIS HAS ALLOWED THE SURFACE DEW
POINTS TO INCH BACK UP SOME AS WELL. THE URBAN CENTERS ARE COOLING
MUCH SLOWER, AND AS OF 01Z PHILADELPHIA /KPHL/ WAS STILL 91
DEGREES. ONCE AGAIN, A WARM AND MUGGY NIGHT IS IN STORE.
LOW TEMPERATURES WERE MOSTLY A GFS/NAM MOS BLEND WITH SOME MINOR
TWEAKS. THE HOURLY GRIDS WERE INITIALIZED WITH THE 01Z SURFACE
OBS AND THEN SOME BLENDING IN OF THE LAMP/LAV GUIDANCE WAS USED.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
WITH SOME SLIGHTLY DRIER AIR IN PLACE TOMORROW, ACTUAL AIR
TEMPERATURES SHOULD EITHER BE THE SAME AS TODAY OR A DEGREE OR TWO
HIGHER. BUT WITH DEWPOINTS DROPPING 5 TO 10 DEGREES, APPARENT
TEMPERATURES SHOULD BE SLIGHTLY COOLER THAN WHAT WE`RE EXPERIENCING
TODAY. THAT SAID, THE EXCESSIVE HEAT WARNING FOR THE URBAN AREAS
WILL STICK, BUT WE WILL NOT BE ISSUING ANY OTHER ADVISORIES LIKE WE
HAVE UP TODAY.
SO TEMPS WILL TOP OUT IN THE MID 90S IN MOST SPOTS TOMORROW. THE
POCONOS SHOULD TOP OUT AROUND 90. WINDS WILL BE OUT OF THE NORTH,
LESS THAN 10 MPH UNDER MOSTLY SUNNY SKIES.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
THE 500MB 12Z UA ANALYSIS HAD A BOATLOAD OF 599 DM HEIGHTS IN THE
OHIO VALLEY THIS MORNING WITH THE LATEST HEAT RIDGE. ACCORDING TO
METEOROLOGIST TOM GREEN, THE 600 DM HEIGHT OFF THE PBZ SOUNDING LAST
NIGHT IS BELIEVED (BUT NOT CONFIRMED) TO BE THE FIRST TIME THAT HAS
EVER HAPPENED THERE.
THE GFS INITIALIZATION OVERALL LOOKED PRETTY GOOD AND SLIGHTLY
BETTER THAN THE WRF-NMMB. THE LARGER GEOGRAPHICAL HEAT RIDGE LOOKS
BETTER (WELL SORT OF). DP/DTG THIS 12Z RUN IS SHOWING A ZERO SUM
GAIN AS THE RIDGE IS RETROGRADING FASTER, BUT IS ALSO LARGER LEAVING
SIMILAR HEIGHT VALUES. THE 12Z GFS ENSEMBLE MEAN IS PRETTY CLOSE TO
THE OPERATIONAL RUN, SLIGHTLY SLOWER OVERALL.
GIVEN THE ACCUMULATIVE EFFECT OF HEAT AND WHAT LOOKS LIKE 99.4%
ASSURED OF REACHING INTO THE MIDDLE 90S ALONG THE I95 URBAN CORRIDOR
INTO FRIDAY, WE DECIDED TO FORGO THE MULTIPLE HEADLINES AND EXTEND
THE EXCESSIVE HEAT WARNING THROUGH THE WORK WEEK. IN OTHER AREAS,
THURSDAY AND FRIDAY LOOK LIKE ADVISORY, POSSIBLY WARNING HEADLINE
DAYS, A LITTLE IFFIER FOR WEDNESDAY WHERE BORDERLINE HEAT ADVISORY
CRITERIA MAY BE MET. IN THESE AREAS, WE WILL CONTINUE MENTION IN THE
HWO. CONVECTIVE-WISE THE BREAK IN THE HEAT COULD COME WITH THE PRICE
OF AN ORGANIZED LINE OF STORMS ON SATURDAY. THAT IS DAYS AWAY AND
THERE IS UNCERTAINTY HOW THIS WILL AFFECT OUR AREA.
WE ARE BANKING ON A 95ISH HIGH FOR PHL TODAY AS THE TEMPLATE FOR
FUTURE DAYS MAX TEMPS. THE COMBINATION OF HOME GROWN (VS CENTRAL
CONUS BAKING) HEAT AND ALL OUR RECENT WETNESS WILL LIKELY PRECLUDE
MOST OF US FROM HITTING 100F AIR TEMPERATURES, IF THAT IS ANY
CONSOLATION.
THE SHIFT OF THE WINDS TO THE NORTH ON TUESDAY AND RELATIVE CLEAR
SKIES AND LIGHT WINDS WILL GIVE NON URBAN AREAS A BIT OF A NIGHT
TIME REPRIEVE FROM THE HEAT AS STAT GUIDANCE HAS TRENDED DOWNWARD
FROM A COUPLE OF DAYS AGO. MIN TEMPS ARE A BLEND OF CONTINUITY AND
THIS NEW GUIDANCE, STILL LIKELY FOR MINS TO ONLY FALL TO THE MID TO
UPPER 70S IN URBAN CENTERS.
ON WEDNESDAY WE ARE EXPECTING THE CAP TO HOLD WITH THE CONVECTIVE
TEMP VERY CLOSE TO THE MAX TEMP. NO THUNDER IN THE FORECAST. WE ARE
GETTING MIXED MESSAGES WITH THE THERMAL FIELDS, 1000-850MB THICK
SUGGEST EQUAL MAXES FROM TUE, WHILE 850S AND 925S SUGGEST A DEGREE
HIGHER. WE HAVE OPTED FOR ABOUT THE SAME. WE SHOULD MIX UP TO 850MB
AND WITH THE FCST AIR MASS EXPECTED TO BE RELATIVELY DRY, DEW POINT
STAT GUIDANCE DROPPING INTO THE MID TO UPPER 60S SEEMS LOGICAL. HEAT
INDEX VALUES IN URBAN CENTERS GET TO ABOUT 100F AND SERN CWA. THEY
MAY FALL JUST SHORT (POCONOS SHOULD REMAIN WELL BELOW) ELSEWHERE. SO
NO HEAT HEADLINES FOR OTHER LOCALES.
MUGGIER NIGHT WEDNESDAY NIGHT AS DEW POINTS WILL START OUT HIGHER
WITH A 1-3F BUMP UP IN MIN TEMPS FROM TUESDAY NIGHT. ON THURSDAY
BOTH THE GFS AND WRF-NMMB HAVE SUFFICIENT MOISTURE FORECAST FOR THE
CONVECTIVE TEMPERATURE TO BE REACHED. THEY ALSO HAVE A HINT OF A LEE
SIDE TROF FORMING AS A POSSIBLE CONVECTIVE FOCUS AS COULD BE THE SEA
AND BAY BREEZE FRONTS. WHILE WE ARE NOT EXPECTING ORGANIZED SEVERE,
THE POSSIBILITY OF ISOLATED PULSE TYPE SEVERE IS NOT OUT OF THE
QUESTION. THE SAME CAN BE SAID FOR FRIDAY. ON FRIDAY, AN EVEN UGLIER
COMBINATION OF TEMPERATURES AND DEW POINTS IS EXPECTED. MAX TEMPS
WERE BUMPED UP ABOUT A DEGREE, BUT HIGHER DEW POINTS ARE BRINGING
HEAT INDICES AT OR ABOVE 100F TO A LARGER PART OF OUR CWA.
AFTER ANOTHER MUGGY NIGHT, THE HEAT AND HUMIDITY MAY PEAK ON FRIDAY.
THE GFS ONCE AGAIN IS THE MOST BULLISH WITH THIS IDEA. UNLESS THERE
ARE CONSIDERABLE DEBRIS CLOUDS AROUND, AT THE LEAST MID 90S FOR
HIGHS IN THE URBAN CORRIDOR APPEAR LIKELY. COUPLED WITH WHAT SHOULD
BE HIGHER AND POOLING DEW POINTS AS THE COLD FRONT COMES CLOSER WE
HAVE THE HIEST FCST HEAT INDICES FOR THIS WEEK. MAX TEMPS WERE KEPT
ABOUT THE SAME.
SATURDAY LOOKS TO BE THE MOST CONVECTIVELY ACTIVE DAY OF THE WEEK.
SPC ALREADY HAS NORTHERN AREAS OF OUR CWA IN THEIR OUTLOOK FOR
POSSIBLE SEVERE WEATHER. AS THE JET STREAM DIPS SOUTHWARD, THE FCST
BULK SHEAR VALUES DO LOOK MORE FAVORABLE FOR ORGANIZED SEVERE AND
THE MID LEVEL LAPSE RATES AT THIS JUNCTURE ARE NOT FORECAST TO BE AN
IMPEDING FORCE. WE HAVE TO SEE HOW FRIDAY`S AND FRIDAY NIGHT`S
UPSTREAM CONVECTION AFFECTS US. FOR NOW WE CARRY THE HIEST POPS OF
THE WEEK IN THIS FORECAST PERIOD. SATURDAY COULD ALSO BE
PROBLEMATICAL FOR HEAT PENDING ON THE FRONT`S TIMING. MODELS OFTEN
GIVE CLOUDS TOO MUCH CREDIT ON THESE DAYS ON DAMPENING MAX TEMPS.
THEN FOR SUNDAY AND MONDAY WE KEPT IN LOWER CHANCES AS A SECOND FRONT
IS FORECAST TO MOVE THROUGH AND ALSO THE POSSIBILITY OF A WAVE
FORMING ON THE FRONT. THE PASSING OF THE FIRST FRONT SHOULD BRING
MORE TOLERABLE TEMPERATURES BACK INTO THE AREA.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
TONIGHT...VFR. WEST-NORTHWEST WINDS NEAR 5 KNOTS, BECOMING
NORTHERLY LATE. ANY MVFR FOG LATE SHOULD BE LOCALIZED, MAINLY AT
KRDG AND KMIV.
TUESDAY...PERHAPS RATHER LOCALIZED MVFR FOG EARLY, OTHERWISE VFR
WITH FEW TO SCATTERED CUMULUS DEVELOPING WITH BASES NEAR 5,000
FEET. NORTHERLY WINDS NEAR 10 KNOTS, ALTHOUGH PERHAPS SHIFTING TO
THE EAST OR SOUTHEAST IN THE AFTERNOON AT KACY.
OUTLOOK...
TUESDAY NIGHT THROUGH FRIDAY...MAINLY VFR WITH LATE NIGHT AND EARLY
MORNING VISIBILITY RESTRICTIONS IN HAZE POSSIBLE EACH DAY.
FRIDAY NIGHT AND ESPECIALLY SATURDAY...SOME MVFR TO IFR CONDITIONS
IN MORNING FOG AND HAZE AS WELL AS SHOWERS AND THUNDERSTORMS. GUSTY
WINDS FROM THUNDERSTORMS POSSIBLE.
&&
.MARINE...
SOUTHWEST WINDS 10 KT OR LESS THIS EVENING WILL BECOME NORTHWEST
LATE DAYBREAK. WINDS WILL GO NORTH-NORTHEAST TUESDAY AT THE SAME
SPEEDS. SEAS MAINLY 2 TO 3 FEET THROUGH TUESDAY AFTERNOON.
OUTLOOK...
SCA HEADLINES ARE NOT ANTICIPATED INTO FRIDAY MORNING ON THE OCEAN
AND THROUGH THE OUTLOOK PERIOD ON DELAWARE BAY. LATER FRIDAY INTO
SATURDAY ON THE OCEAN, THE INCREASING SOUTHWESTERLY FLOW PRECEDING
THE COLD FRONT COULD BRING SEAS UP TO SMALL CRAFT ADVISORY CRITERIA.
WE HAVE TAKEN AROUND A FOOT OFF OF WAVE WATCH GUIDANCE BASED ON ITS
PREVIOUS PERFORMANCE IN SIMILAR EVENTS WHICH BRINGS US NEAR THE
THRESHOLD OF SMALL CRAFT ADVISORY CRITERIA VS BEING WELL INTO IT.
&&
.CLIMATE...
BESIDE THE DAYTIME HEAT, THERE HAVE NOT BEEN TOO MANY PLEASANT
NIGHTS FOR SLEEPING. PRIOR TO THIS WEEK MORE OF THE ABOVE NORMAL
TEMPERATURE DEPARTURES THIS MONTH HAVE BEEN ATTRIBUTED TO THE NIGHTS
AS DEW POINT LEVELS HAVE NOT BEEN PLEASANT AT ALL. SO MUCH SO THAT
TO DATE, THE NIGHTMARISH AVERAGE MINIMUM TEMPERATURE IN PHILADELPHIA
OF 74.6 DEGREES IS THE WARMEST ON RECORD FOR ANY MONTH DATING BACK
TO 1874.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...EXCESSIVE HEAT WARNING UNTIL 8 PM EDT FRIDAY FOR PAZ070-071-
102-104-106.
NJ...EXCESSIVE HEAT WARNING UNTIL 8 PM EDT FRIDAY FOR NJZ015-
017>019.
DE...EXCESSIVE HEAT WARNING UNTIL 8 PM EDT FRIDAY FOR DEZ001.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...DRAG/GIGI
NEAR TERM...GORSE
SHORT TERM...KRUZDLO
LONG TERM...GIGI
AVIATION...DRAG/GIGI/GORSE
MARINE...GIGI/KRUZDLO
CLIMATE...GIGI
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
818 PM EDT MON JUL 15 2013
.SYNOPSIS...
AN OPPRESSIVE HIGH PRESSURE SYSTEM ALONG THE EASTERN SEABOARD IS
EXPECTED TO REMAIN NEARLY STATIONARY THROUGH FRIDAY. A SLOWLY
SOUTHWARD SAGGING COLD FRONT IS FORECAST TO REACH THE NORTHERN
GREAT LAKES ON THURSDAY, LAKE ONTARIO AND LAKE ERIE ON FRIDAY AND
THEN MOVE INTO OUR AREA ON SATURDAY. A SECOND COLD FRONT FROM
EASTERN CANADA IS THEN EXPECTED TO MOVE THROUGH OUR REGION LATER
SUNDAY INTO MONDAY.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
THE EXCESSIVE HEAT WARNING REMAINS IN EFFECT. A QUICK UPDATE WAS
SENT TO EXPIRE THE HEAT ADVISORY.
A THERMAL SURFACE TROUGH BISECTS THE CWA EARLY THIS EVENING
BENEATH A BUILDING UPPER-LEVEL RIDGE. THERE APPEARS TO BE A SUBTLE
SHORT WAVE ROUNDING THE EASTERN SIDE OF THE RIDGE, AND DESPITE NOT
MUCH FORCING WITH IT THE COMBINATION OF HEAT AND HUMIDITY AND JUST
ENOUGH SURFACE FOCUS HAS LEAD TO A FEW ISOLATED SHOWERS AND
THUNDERSTORMS. THE MAJORITY OF THE CWA IS EXPECTED TO REMAIN RAIN-
FREE, HOWEVER THE HRRR AND THE SPC WRF INDICATE SOME ADDITIONAL
DEVELOPMENT IS POSSIBLE ACROSS THE SOUTHERN ZONES THIS EVENING.
WHILE OUR CONFIDENCE IS ON THE LOWER SIDE, WE MAINTAINED A SLIGHT
CHC POP TO ACCOUNT FOR THIS POTENTIAL.
THERE IS NOT A LOT OF WIND HOWEVER THE FLOW IS FORECAST TO BECOME
MORE NORTHERLY DURING THE NIGHT, WHICH MAY TRY AND PULL DOWN SOME
DRIER AIR. THIS MAY NOT BE REALIZED THOUGH HOWEVER ACROSS MUCH OF
THE CWA GIVEN LIGHT ENOUGH SURFACE WINDS /REDUCED VERTICAL MIXING/
AN ENOUGH LINGERING LOW-LEVEL MOISTURE IN PLACE. WE DID MAINTAIN A
SIMILAR TREND IN DEW POINTS FROM CONTINUITY, WHICH SHOWS A LITTLE
BIT OF LOWERING ESPECIALLY ACROSS THE FAR NORTH.
LOW TEMPERATURES WERE MOSTLY A GFS/NAM MOS BLEND WITH SOME MINOR
TWEAKS. THE HOURLY GRIDS WERE INITIALIZED WITH THE LATEST SURFACE OBS
AND THEN SOME BLENDING IN OF THE LAMP/LAV GUIDANCE WAS USED.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
WITH SOME SLIGHTLY DRIER AIR IN PLACE TOMORROW, ACTUAL AIR
TEMPERATURES SHOULD EITHER BE THE SAME AS TODAY OR A DEGREE OR TWO
HIGHER. BUT WITH DEWPOINTS DROPPING 5 TO 10 DEGREES, APPARENT
TEMPERATURES SHOULD BE SLIGHTLY COOLER THAN WHAT WE`RE EXPERIENCING
TODAY. THAT SAID, THE EXCESSIVE HEAT WARNING FOR THE URBAN AREAS
WILL STICK, BUT WE WILL NOT BE ISSUING ANY OTHER ADVISORIES LIKE WE
HAVE UP TODAY.
SO TEMPS WILL TOP OUT IN THE MID 90S IN MOST SPOTS TOMORROW. THE
POCONOS SHOULD TOP OUT AROUND 90. WINDS WILL BE OUT OF THE NORTH,
LESS THAN 10 MPH UNDER MOSTLY SUNNY SKIES.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
THE 500MB 12Z UA ANALYSIS HAD A BOATLOAD OF 599 DM HEIGHTS IN THE
OHIO VALLEY THIS MORNING WITH THE LATEST HEAT RIDGE. ACCORDING TO
METEOROLOGIST TOM GREEN, THE 600 DM HEIGHT OFF THE PBZ SOUNDING LAST
NIGHT IS BELIEVED (BUT NOT CONFIRMED) TO BE THE FIRST TIME THAT HAS
EVER HAPPENED THERE.
THE GFS INITIALIZATION OVERALL LOOKED PRETTY GOOD AND SLIGHTLY
BETTER THAN THE WRF-NMMB. THE LARGER GEOGRAPHICAL HEAT RIDGE LOOKS
BETTER (WELL SORT OF). DP/DTG THIS 12Z RUN IS SHOWING A ZERO SUM
GAIN AS THE RIDGE IS RETROGRADING FASTER, BUT IS ALSO LARGER LEAVING
SIMILAR HEIGHT VALUES. THE 12Z GFS ENSEMBLE MEAN IS PRETTY CLOSE TO
THE OPERATIONAL RUN, SLIGHTLY SLOWER OVERALL.
GIVEN THE ACCUMULATIVE EFFECT OF HEAT AND WHAT LOOKS LIKE 99.4%
ASSURED OF REACHING INTO THE MIDDLE 90S ALONG THE I95 URBAN CORRIDOR
INTO FRIDAY, WE DECIDED TO FORGO THE MULTIPLE HEADLINES AND EXTEND
THE EXCESSIVE HEAT WARNING THROUGH THE WORK WEEK. IN OTHER AREAS,
THURSDAY AND FRIDAY LOOK LIKE ADVISORY, POSSIBLY WARNING HEADLINE
DAYS, A LITTLE IFFIER FOR WEDNESDAY WHERE BORDERLINE HEAT ADVISORY
CRITERIA MAY BE MET. IN THESE AREAS, WE WILL CONTINUE MENTION IN THE
HWO. CONVECTIVE-WISE THE BREAK IN THE HEAT COULD COME WITH THE PRICE
OF AN ORGANIZED LINE OF STORMS ON SATURDAY. THAT IS DAYS AWAY AND
THERE IS UNCERTAINTY HOW THIS WILL AFFECT OUR AREA.
WE ARE BANKING ON A 95ISH HIGH FOR PHL TODAY AS THE TEMPLATE FOR
FUTURE DAYS MAX TEMPS. THE COMBINATION OF HOME GROWN (VS CENTRAL
CONUS BAKING) HEAT AND ALL OUR RECENT WETNESS WILL LIKELY PRECLUDE
MOST OF US FROM HITTING 100F AIR TEMPERATURES, IF THAT IS ANY
CONSOLATION.
THE SHIFT OF THE WINDS TO THE NORTH ON TUESDAY AND RELATIVE CLEAR
SKIES AND LIGHT WINDS WILL GIVE NON URBAN AREAS A BIT OF A NIGHT
TIME REPRIEVE FROM THE HEAT AS STAT GUIDANCE HAS TRENDED DOWNWARD
FROM A COUPLE OF DAYS AGO. MIN TEMPS ARE A BLEND OF CONTINUITY AND
THIS NEW GUIDANCE, STILL LIKELY FOR MINS TO ONLY FALL TO THE MID TO
UPPER 70S IN URBAN CENTERS.
ON WEDNESDAY WE ARE EXPECTING THE CAP TO HOLD WITH THE CONVECTIVE
TEMP VERY CLOSE TO THE MAX TEMP. NO THUNDER IN THE FORECAST. WE ARE
GETTING MIXED MESSAGES WITH THE THERMAL FIELDS, 1000-850MB THICK
SUGGEST EQUAL MAXES FROM TUE, WHILE 850S AND 925S SUGGEST A DEGREE
HIGHER. WE HAVE OPTED FOR ABOUT THE SAME. WE SHOULD MIX UP TO 850MB
AND WITH THE FCST AIR MASS EXPECTED TO BE RELATIVELY DRY, DEW POINT
STAT GUIDANCE DROPPING INTO THE MID TO UPPER 60S SEEMS LOGICAL. HEAT
INDEX VALUES IN URBAN CENTERS GET TO ABOUT 100F AND SERN CWA. THEY
MAY FALL JUST SHORT (POCONOS SHOULD REMAIN WELL BELOW) ELSEWHERE. SO
NO HEAT HEADLINES FOR OTHER LOCALES.
MUGGIER NIGHT WEDNESDAY NIGHT AS DEW POINTS WILL START OUT HIGHER
WITH A 1-3F BUMP UP IN MIN TEMPS FROM TUESDAY NIGHT. ON THURSDAY
BOTH THE GFS AND WRF-NMMB HAVE SUFFICIENT MOISTURE FORECAST FOR THE
CONVECTIVE TEMPERATURE TO BE REACHED. THEY ALSO HAVE A HINT OF A LEE
SIDE TROF FORMING AS A POSSIBLE CONVECTIVE FOCUS AS COULD BE THE SEA
AND BAY BREEZE FRONTS. WHILE WE ARE NOT EXPECTING ORGANIZED SEVERE,
THE POSSIBILITY OF ISOLATED PULSE TYPE SEVERE IS NOT OUT OF THE
QUESTION. THE SAME CAN BE SAID FOR FRIDAY. ON FRIDAY, AN EVEN UGLIER
COMBINATION OF TEMPERATURES AND DEW POINTS IS EXPECTED. MAX TEMPS
WERE BUMPED UP ABOUT A DEGREE, BUT HIGHER DEW POINTS ARE BRINGING
HEAT INDICES AT OR ABOVE 100F TO A LARGER PART OF OUR CWA.
AFTER ANOTHER MUGGY NIGHT, THE HEAT AND HUMIDITY MAY PEAK ON FRIDAY.
THE GFS ONCE AGAIN IS THE MOST BULLISH WITH THIS IDEA. UNLESS THERE
ARE CONSIDERABLE DEBRIS CLOUDS AROUND, AT THE LEAST MID 90S FOR
HIGHS IN THE URBAN CORRIDOR APPEAR LIKELY. COUPLED WITH WHAT SHOULD
BE HIGHER AND POOLING DEW POINTS AS THE COLD FRONT COMES CLOSER WE
HAVE THE HIEST FCST HEAT INDICES FOR THIS WEEK. MAX TEMPS WERE KEPT
ABOUT THE SAME.
SATURDAY LOOKS TO BE THE MOST CONVECTIVELY ACTIVE DAY OF THE WEEK.
SPC ALREADY HAS NORTHERN AREAS OF OUR CWA IN THEIR OUTLOOK FOR
POSSIBLE SEVERE WEATHER. AS THE JET STREAM DIPS SOUTHWARD, THE FCST
BULK SHEAR VALUES DO LOOK MORE FAVORABLE FOR ORGANIZED SEVERE AND
THE MID LEVEL LAPSE RATES AT THIS JUNCTURE ARE NOT FORECAST TO BE AN
IMPEDING FORCE. WE HAVE TO SEE HOW FRIDAY`S AND FRIDAY NIGHT`S
UPSTREAM CONVECTION AFFECTS US. FOR NOW WE CARRY THE HIEST POPS OF
THE WEEK IN THIS FORECAST PERIOD. SATURDAY COULD ALSO BE
PROBLEMATICAL FOR HEAT PENDING ON THE FRONT`S TIMING. MODELS OFTEN
GIVE CLOUDS TOO MUCH CREDIT ON THESE DAYS ON DAMPENING MAX TEMPS.
THEN FOR SUNDAY AND MONDAY WE KEPT IN LOWER CHANCES AS A SECOND FRONT
IS FORECAST TO MOVE THROUGH AND ALSO THE POSSIBILITY OF A WAVE
FORMING ON THE FRONT. THE PASSING OF THE FIRST FRONT SHOULD BRING
MORE TOLERABLE TEMPERATURES BACK INTO THE AREA.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
TONIGHT...VFR. WEST-NORTHWEST WINDS AROUND 10 KNOTS EARLY, THEN BECOMING
NORTHERLY 4-8 KNOTS. AN ISOLATED SHOWER OR THUNDERSTORM THIS
EVENING. ANY LIGHT FOG LATE SHOULD BE RATHER LOCALIZED.
TUESDAY...VFR WITH FEW TO SCATTERED CUMULUS DEVELOPING WITH BASES
NEAR 5,000 FEET. NORTHERLY WINDS NEAR 10 KNOTS, ALTHOUGH PERHAPS
SHIFTING TO THE EAST OR SOUTHEAST IN THE AFTERNOON AT KACY.
OUTLOOK...
TUESDAY NIGHT THROUGH FRIDAY...MAINLY VFR WITH LATE NIGHT AND EARLY
MORNING VISIBILITY RESTRICTIONS IN HAZE POSSIBLE EACH DAY.
FRIDAY NIGHT AND ESPECIALLY SATURDAY...SOME MVFR TO IFR CONDITIONS
IN MORNING FOG AND HAZE AS WELL AS SHOWERS AND THUNDERSTORMS. GUSTY
WINDS FROM THUNDERSTORMS POSSIBLE.
&&
.MARINE...
WEST WINDS 10 KT OR LESS THIS EVENING WILL BECOME NORTHWEST BY
DAYBREAK. WINDS WILL GO NORTH TOMORROW AT THE SAME SPEEDS. SEAS
MAINLY 2 TO 3 FEET THROUGH TOMORROW AFTERNOON.
OUTLOOK...
SCA HEADLINES ARE NOT ANTICIPATED INTO FRIDAY MORNING ON THE OCEAN
AND THROUGH THE OUTLOOK PERIOD ON DELAWARE BAY. LATER FRIDAY INTO
SATURDAY ON THE OCEAN, THE INCREASING SOUTHWESTERLY FLOW PRECEDING
THE COLD FRONT COULD BRING SEAS UP TO SMALL CRAFT ADVISORY CRITERIA.
WE HAVE TAKEN AROUND A FOOT OFF OF WAVE WATCH GUIDANCE BASED ON ITS
PREVIOUS PERFORMANCE IN SIMILAR EVENTS WHICH BRINGS US NEAR THE
THRESHOLD OF SMALL CRAFT ADVISORY CRITERIA VS BEING WELL INTO IT.
&&
.CLIMATE...
BESIDE THE DAYTIME HEAT, THERE HAVE NOT BEEN TOO MANY PLEASANT
NIGHTS FOR SLEEPING. PRIOR TO THIS WEEK MORE OF THE ABOVE NORMAL
TEMPERATURE DEPARTURES THIS MONTH HAVE BEEN ATTRIBUTED TO THE NIGHTS
AS DEW POINT LEVELS HAVE NOT BEEN PLEASANT AT ALL. SO MUCH SO THAT
TO DATE, THE NIGHTMARISH AVERAGE MINIMUM TEMPERATURE IN PHILADELPHIA
OF 74.6 DEGREES IS THE WARMEST ON RECORD FOR ANY MONTH DATING BACK
TO 1874.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...EXCESSIVE HEAT WARNING UNTIL 8 PM EDT FRIDAY FOR PAZ070-071-
102-104-106.
NJ...EXCESSIVE HEAT WARNING UNTIL 8 PM EDT FRIDAY FOR NJZ015-
017>019.
DE...EXCESSIVE HEAT WARNING UNTIL 8 PM EDT FRIDAY FOR DEZ001.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...DRAG/GIGI
NEAR TERM...GORSE
SHORT TERM...KRUZDLO
LONG TERM...GIGI
AVIATION...DRAG/GIGI/GORSE
MARINE...GIGI/KRUZDLO
CLIMATE...GIGI
AREA FORECAST DISCUSSION
NWS MIAMI FL
241 PM EDT SUN JUL 14 2013
.DISCUSSION...
THE AREA OF PERSISTENT CONVERGENCE AND THUNDERSTORMS THAT HAS
BEEN AFFECTING AREAS AROUND NAPLES THIS MORNING MOVED TO THE
NORTHEAST INTO THE EVERGLADES DURING THE LATE MORNING AND IT IS
NOW AFFECTING AREAS AROUND THE LAKE.
THE 12Z RUN OF THE GFS AND THE LATEST ECMWF PORTRAY THE SAME GENERAL
REASONING THAN THE PAST FEW DAYS: A TROUGH OF LOW PRESSURE OVER THE
CENTRAL US SURROUNDED BY TWO LARGE AREAS OF HIGH PRESSURE. THE
FORECAST STILL CALLS FOR THE AREA OF HIGH PRESSURE IN THE ATLANTIC
TO INTENSIFY AND RETROGRADE OVER THE NE US BETWEEN NOW AND THE
MONDAY-TUESDAY TIME FRAME. BY WEDNESDAY, THE ATLANTIC OCEAN IS
DOMINATED BY TWO LARGE AREAS OF HIGH PRESSURE ONE OVER NORTH AFRICA
AND THE SECOND OVER THE NORTHERN US, WITH MOST OF THE SUBTROPICAL
ATLANTIC UNDER TRADE WINDS.
BY THE MIDDLE OF THE WEEK THE AREA OF HIGH PRESSURE OVER NORTH
AMERICA BEGINS TO WEAKEN SOMEWHAT. THE WEATHER OVER SOUTH FLORIDA
WILL BE DRIVEN BY FLUCTUATIONS IN MOISTURE MOVING WESTWARD ON THE
SOUTHERN PERIPHERY OF THE ATLANTIC HIGH PRESSURE AND SLIGHT CHANGES
IN THE MID LEVEL TEMPERATURES AS SMALL POCKETS OF COOL AIR TRAVEL
AROUND THE AREA OF HIGH PRESSURE IN THE ATLANTIC.
THE INCREASED MOISTURE ASSOCIATED WITH THE REMNANTS WILL CEASE TO
AFFECT SOUTH FLORIDA AFTER TODAY.
THE STEERING WINDS ARE TRANSITIONING TO THE SOUTHEAST TODAY AND ARE
FORECAST TO REMAIN SOUTHEASTERLY FOR THE MOST OF THIS COMING WEEK. A
WEAKNESS IN THE HIGH PRESSURE WILL MOVE FROM EAST TO WEST ON MONDAY
OVER THE BAHAMA ISLANDS. THIS WILL BRING A BRIEF PERIOD OF
NORTHEASTERLY WINDS ON MONDAY MORNING. THIS COULD GENERATE AN
ENHANCEMENT OF MORNING SHOWERS FROM STREAMERS ALONG THE ATLANTIC
COASTAL WATERS AND ENHANCE MOISTURE CONVERGENCE IN THE WEST COAST
DURING THE MORNING HOURS AND POSSIBLY CONCENTRATING THE SHOWER
AND THUNDERSTORM ACTIVITY OVER COLLIER COUNTY IN THE AFTERNOON/EVENING.
WIDESPREAD SHOWERS AND THUNDERSTORMS ARE FORECAST FOR TODAY WITH THE
MAIN CONCENTRATION OVER THE NORTHERN AND WESTERN PORTIONS AS THE
EVENING PROGRESSES. THE INTERACTION OF STORMS WITH OUTFLOW
BOUNDARIES COULD STILL TRIGGER A FEW STORMS OVER THE WESTERN METRO
AREAS THIS AFTERNOON AND EVENING. FOR MONDAY AFTERNOON AND
EVENING THE MAIN CONCENTRATION OF SHOWERS AND STORMS IS EXPECTED FOR
THE INTERIOR AND WEST, AS THE EAST TO SOUTHEAST FLOW GETS
ESTABLISHED.
THE VISIBLE SATELLITE IMAGE SHOWS THE LEADING EDGE OF THE EXPANDING
SUBTROPICAL RIDGE CROSSING THE BAHAMA ISLANDS AROUND 1 PM TODAY. THIS
AREA COINCIDES WITH A DRY SLOT AT 850 MB, AROUND THE HEIGHT OF THE
BASE OF THE SUBTROPICAL INVERSION. ONCE THIS DRY AIR REACHES THE SE
COAST THE CHANCES FOR THUNDERSTORMS WILL DIMINISH SUBSTANTIALLY FOR
THE EAST COAST. HOWEVER, THIS FEATURE IS NOT EXPECTED TO ARRIVE THE
EAST COAST FOR 7 MORE HOURS. FOR NOW HAVE KEPT A 40 PERCENT OF
SHOWERS OVER THE SOUTHERN ATLANTIC WATERS AND A 50 PERCENT FOR THE
EAST COAST METRO AREAS OF MIAMI-DADE. BUT IT IS POSSIBLE THAT SOME
MIXING OF DRY AIR AHEAD OF THE FEATURE COULD START AFFECTING THE
EAST COAST IN THE NEXT FEW HOURS. AREAS TO THE INTERIOR STILL HAVE A
70 PERCENT CHANCE OF SHOWERS AND STORMS FOR THIS AFTERNOON AND
EVENING. A DECK OF MID LEVEL CLOUDS OVER PARTS OF MIAMI-DADE CAN
SLOW DOWN CONVECTION IN THE SHORT TERM. ANOTHER VARIABLE
COMPLICATING THE FORECAST FOR THIS EVENING FOR THE SOUTHEAST COAST
IS THE PRESENCE OF SAHARAN DUST WELL DETECTED BY LIDAR AND THE NAVY
AND GFS AEROSOL MODELS. THE DRY AIR ABOVE THE SURFACE MIXED WITH
THE DUST COULD DIMINISH THE WIDESPREAD CONVECTION BUT STILL ALLOW FOR ONE OR
TWO STRONG STORMS.
&&
.AVIATION...
THE PERIOD BEGINS WITH MAINLY LINGERING LIGHT RAIN OVER THE APF
TERMINAL AS MOST OF THE HEAVIER ACTIVITY HAS SHIFTED INLAND FROM
COLLIER TO GLADES COUNTY. THE LATEST HRRR MODEL REFLECTIVITY SHOW
THE BULK OF THE AFTERNOON ACTIVITY CONTINUING TO DEVELOP OVER THE
INTERIOR AND NORTHERN AREAS THROUGH THE REMAINDER OF THE AFTERNOON
HOURS. FOR NOW...WE WILL CONTINUE TO CARRY VCTS ALONG THE EAST COAST
AND UPDATE AS CONDITIONS EVOLVE. THIS ACTIVITY SHOULD WEAKEN AND
TREND DOWN THROUGH THE OVERNIGHT HOURS TONIGHT WITH LIGHT EASTERLY
FLOW RETURNING ACROSS THE AREA. LIGHT TO MODERATE EASTERLY FLOW ON
MONDAY SHOULD TRANSLATE TO THE AFTERNOON ACTIVITY SETTING UP INLAND
OF THE EAST COAST ACROSS THE INTERIOR AND GULF COAST THROUGH THE
AFTERNOON HOURS.
&&
.MARINE...
TRANQUIL WIND AND SEAS ARE EXPECTED THROUGH THE PERIOD OUTSIDE OF
ROUGHER SEAS NEAR THUNDERSTORMS. A GENERAL LIGHT TO MODERATE EAST TO
SOUTHEAST WIND IS ANTICIPATED THROUGH THE MIDDLE OF NEXT WEEK.
&&
FIRE WEATHER...
NO FIRE WEATHER CONCERNS OR FOG IS ANTICIPATED THIS WEEK. HIGH
RELATIVE HUMIDITY AND AT LEAST SCATTERED SHOWERS WILL PREVAIL. THE
TYPICAL AREA WITH LOWER RELATIVE HUMIDITIES, GLADES AND HENDRY, WILL
MAINTAIN VALUES ABOVE 55 PERCENT AND ABOVE 48 PERCENT FOR THE
LATER PART OF THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 73 87 76 88 / 40 20 10 30
FORT LAUDERDALE 75 88 79 89 / 40 30 20 30
MIAMI 74 89 78 89 / 40 30 20 30
NAPLES 71 88 73 92 / 40 50 20 40
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...71/JE
AVIATION/RADAR...85/AG
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
722 PM EDT MON JUL 15 2013
.UPDATE...
22Z SURFACE ANALYSIS SHOWS HIGH PRESSURE BUILDING IN FROM THE NE
ACROSS THE CWFA. OVER THE LAST FEW HOURS...MOST OF THE STRONGER
AFTERNOON CONVECTION HAS MOVED OFF TO THE WEST. ADDITIONAL SHOWERS
IN THE EAST ARE MOVING INTO AREAS THAT HAVE BEEN SLIGHTLY
STABILIZED WITH EARLIER ACTIVITY. THE LATEST RUNS OF THE HRRR SHOW
A DIMINISHING TREND IN CONVECTION AFTER 02Z. THIS SEEMS REASONABLE
AND HAVE FOLLOWED CLOSELY. HAVE ALSO REMOVED ALL MENTION OF
ISOLATED POPS AFTER 02AM. HIGH RESOLUTION MODELS ALSO SUPPORT
THIS.
&&
.PREV DISCUSSION... /ISSUED 346 PM EDT MON JUL 15 2013/
SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
A SLUG OF ATLANTIC MOISTURE WILL CONTINUE TO ADVECT WESTWARD ACROSS
THE CWA THIS AFTERNOON INTO EVENING ALONG THE SOUTHERN EXTEND OF AN
UPPER HIGH CENTERED OVER THE OHIO VALLEY. WHILE MLCAPE VALUES ARE
HIGHER TODAY THAN YESTERDAY AT NEAR 2000 J/KG...PWATS ARE NEAR 2.0
INCHES AGAIN AND DEVELOPMENT IS LARGELY TROPICAL IN NATURE. THERE
COULD BE SOME ISOLATED STRONG STORMS BUT NOT EXPECTED ANYTHING
SEVERE.
WHILE THE UPPER RIDGE SLOWLY DAMPENS AND RETROGRADES WEST THROUGH
TUESDAY...CANNOT RULE OUT A CHANCE OF SHOWERS AND THUNDERSTORMS
MAINLY IN THE AFTERNOON WITH CONTINUED EASTERLY FETCH AND DECENT
CAPE. HAVE GONE WITH CHANCE POPS SOUTH AND SLIGHT ELSEWHERE. ANOTHER
LOBE OF ENHANCED DEEPER MOISTURE APPROACHES THE NORTHEAST PART OF
THE AREA TUESDAY NIGHT SO HAVE INCREASED CLOUD COVERAGE...WHILE POPS
SHOULD BE ON THE RISE INTO WEDNESDAY.
FOR TEMPS...USED BLEND OF GUIDANCE AS THIS HAS VERIFIED WELL
RECENTLY. MAX VALUES SHOULD REBOUND TO BACK NEAR NORMAL TUESDAY IN
THE UPPER 80S TO LOW 90S.
BAKER
LONG TERM /WEDNESDAY THROUGH MONDAY/...
NO MAJOR CHANGES IN THE CURRENT EXTENDED FORECAST. HIGH PRESSURE
ALOFT WILL BE OVER THE OH- MID MS VALLEYS TO START THE LONG TERM.
A MOIST AIRMASS WILL STILL BE IN PLACE AS A DEEP EASTERLY FLOW
PATTERN PERSISTS. THIS SHOULD ALLOW A MORE DIURNAL TENDENCY TO ANY
CONVECTION TUESDAY NIGHT AND WEDNESDAY.
THIS PATTERN LOOKS TO CONTINUE ON THURSDAY AND FRIDAY BUT WITH THE
UPPER RIDGE WEAKENING AND THE UPPER FLOW BECOMING MORE WESTERLY FOR
SATURDAY INTO MONDAY. SCATTERED SHOWERS AND THUNDERSTORMS CAN BE
EXPECTED FOR MOST AREAS THROUGH MONDAY WITH THE GREATEST COVERAGE
IN THE AFTERNOON AND EVENING HOURS. THE POTENTIAL FOR SOME
ENHANCEMENT FROM SHORT WAVE ENERGY WILL INCREASE FROM SATURDAY ON
ALONG WITH DEEPER MOISTURE AVAILABLE. ALL IN ALL TEMPERATURES
SHOULD GENERALLY BE CLOSE TO NORMAL WITH THE HIGHS SLIGHTLY BELOW
NORMAL LATER IN THE PERIOD.
BDL/01
&&
.AVIATION...
00Z UPDATE...
SHOWERS/ISO TSRA SHOULD LINGER ACROSS CENTRAL GA FOR THE NEXT FEW
HOURS...BUT THE OVERALL TREND IS DIMINISHING/WEAKENING STORMS.
WILL LEAVE IN VCSH UNTIL AROUND 02Z TO HANDLE THE WEAKER SHOWERS
APPROACHING FROM THE EAST. NOT CONFIDENT THAT LOW IFR CIGS WILL
DEVELOP OVERNIGHT. MODELS HAVE BACKED OFF...BUT WILL KEEP A SCT
IFR DECK WITH A BKN MVFR DECK IN. DO THINK CLOUDS WILL BE MORE SCT
TOMORROW...AND DIURNAL. EAST WINDS THROUGH THE PD.
//ATL CONFIDENCE...00Z UPDATE...
MEDIUM CONFIDENCE FOR CIGS. HIGH CONFIDENCE REMAINING ELEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 70 89 70 91 / 20 20 20 50
ATLANTA 70 88 73 89 / 30 20 20 50
BLAIRSVILLE 65 87 67 86 / 20 20 20 50
CARTERSVILLE 70 90 69 90 / 30 20 20 50
COLUMBUS 72 90 73 91 / 30 30 20 30
GAINESVILLE 70 88 72 88 / 20 20 20 50
MACON 70 89 70 91 / 30 30 20 30
ROME 70 91 69 91 / 30 20 20 50
PEACHTREE CITY 69 87 68 89 / 30 20 20 50
VIDALIA 72 90 72 93 / 30 30 30 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1244 PM CDT SUN JUL 14 2013
.DISCUSSION...
ISSUED 1007 AM CDT SUN JUL 14 2013
NO CHANGES ANTICIPATED TO THE CURRENT FORECAST. UPPER LOW THAT
BROUGHT WIDELY SCATTERED THUNDERSTORMS TO SOUTHERN ILLINOIS
YESTERDAY HAS NOW SHIFTED INTO EASTERN KANSAS. SOUTHEASTERLY FLOW
ON ITS BACKSIDE IS BRINGING INCREASING MOISTURE INTO THE REGION
THIS MORNING...AS EVIDENCED BY UPSTREAM 850MB DEWPOINTS OF 13C AT
BOTH KILN AND KOHX. DESPITE LACK OF GOOD UPPER-LEVEL
SUPPORT...INCREASING MOISTURE AND POSSIBLE WEAKNESS/TROUGH AXIS IN
PRESSURE FIELD MAY SUPPORT ISOLATED CONVECTION LATER THIS
AFTERNOON. 13Z HRRR SHOWS THIS OCCURRING ACROSS MAINLY THE E/SE
KILX CWA AFTER 21Z. WILL CONTINUE TO MENTION ISOLATED THUNDER IN
THE FORECAST ACCORDINGLY...ALTHOUGH THE MAJORITY OF THE AREA WILL
REMAIN WARM AND DRY TODAY.
&&
.AVIATION...
ISSUED 1244 PM CDT SUN JUL 14 2013
SCT DIURNAL CU WILL DEVELOP ACROSS THE AREA THIS AFTERNOON...THEN
WILL FADE AWAY BY SUNSET. WITH CLEAR SKIES AND LIGHT WINDS
EXPECTED OVERNIGHT...PATCHY FOG WILL BE A STRONG POSSIBILITY AS
SURFACE DEWPOINTS HOVER IN THE UPPER 60S. FORECAST SOUNDINGS AND
NUMERIC GUIDANCE BOTH SUPPORT MINOR VISBY RESTRICTIONS...SO HAVE
GONE WITH PREVAILING 4SM AFTER 06Z. ONCE EARLY MORNING FOG
DISSIPATES...NEGATIVE CU-RULE SUGGESTS SCT-BKN CU DEVELOPING FROM
LATE MONDAY MORNING THROUGH THE AFTERNOON. WINDS WILL REMAIN LIGHT
THROUGH THE ENTIRE PERIOD...GENERALLY FROM THE SE AT LESS THAN
10KT.
BARNES
&&
.PREV DISCUSSION...
ISSUED 330 AM CDT SUN JUL 14 2013
SHORT TERM...TODAY THROUGH THURSDAY NIGHT
00Z MODELS ARE IN FAIR AGREEMENT THROUGH MID WEEK AS A HOT AND
HUMID WEEK IS AHEAD FOR CENTRAL AND SOUTHEAST IL. THIS DUE TO
STRONG 597 DM 500 MB HIGH PRESSURE RIDGE OFF THE SOUTHERN NEW
ENGLAND COAST INTO PA/NJ THAT RETROGRADES WESTWARD INTO THE OHIO
VALLEY AND SOUTHERN GREAT LAKES BY TUE AND STAYS NEAR IL AS IT
SLOWLY WEAKENS AND SHIFTS SOUTHWARD LATER THIS WEEK ALLOWING A
FRONTAL BOUNDARY TO SAG SOUTHWARD OVER THE REGION NEXT WEEKEND.
THIS BOUNDARY WILL BRING A BETTER CHANCE OF SHOWERS/THUNDERSTORMS
NEXT WEEKEND.
579 DM 500 MB LOW PRESSURE OVER SE MO MOVE QUICKLY WSW INTO
EASTERN OK BY SUNSET TODAY WHILE 597 DM 500 HIGH PRESSURE RIDGE
SHIFTS WESTWARD ACROSS PA AND INTO THE EASTERN GREAT LAKES REGION.
NOT MUCH LIFTING MECHISMS AROUND IL TODAY BUT INCREASING DEEPER
GULF MOISTURE CONTINUES TO STREAM NW INTO IL WITH PRECIPITABLE
WATER VALUES RISING TO 1.5 TO 2 INCHES THIS AFTERNOON AND HIGHEST
IN SE IL. AIRMASS GETS UNSTABLE THIS AFTERNOON WITH CAPES OF 1000
TO 2000 J/KG SE OF THE IL RIVER AND THIS SHOULD ALLOW ISOLATED
SHOWERS AND THUNDERSTORMS TO DEVELOP FROM MID AFTERNOON INTO EARLY
EVENING UNTIL SUNSET FROM I-72 SOUTH. SUNNY SKIES TO BECOME PARTLY
TO MOSTLY SUNNY IN AFTERNOON WITH HIGHS IN THE MID TO UPPER 80S.
DEWPOINTS IN THE LOW TO MID 60S TO RISE INTO THE UPPER 60S TO NEAR
70F BY AFTERNOON.
HAVE A SLIGHT CHANCE OF CONVECTION UNTIL MID EVENING FROM I-72
SOUTH THEN DRY REST OF TONIGHT WITH LOWS AROUND 70F. HAVE ISOLATED
CONVECTION DEVELOPING AGAIN DURING MONDAY AFTERNOON AND OVER IL
RIVER VALLEY TOO AS UNSTABLE AIRMASS SPREADS FURTHER NW. VERY WARM
AND HUMID WITH HIGHS IN THE UPPER 80S TO NEAR 90F MONDAY WITH
DEWPOINTS IN THE LOWER 70S. AFTERNOON HEAT INDICES IN MID TO UPPER
90S AND A FEW SPOTS IN SE IL BY WABASH RIVER NEARING 100F.
STRONG UPPER LEVEL RIDGE NEARS IL DURING MIDDLE OF THE WEEK
BRINGING HOT AND HUMID CONDITIONS WITH HIGHS IN THE LOWER 90S TUE
THROUGH FRI AND AFTERNOON HEAT INDICES OF 98 TO 105F. HAVE
ISOLATED CONVECTION POSSIBLE EACH AFTERNOON AND EARLY EVENING DURING
THE WORK WEEK AND COVERAGE SHOULD BE LIMITED WITH STRONG UPPER
LEVEL RIDGE NEARBY PROVIDING A CAP. BUT HAVE TROPICAL AIRMASS IN
PLACE WITH DEWPOINTS IN THE LOW TO MID 70S.
LONG TERM...FRIDAY THROUGH SUNDAY
MODELS HAVE TRENDED SLOWER WITH FRONTAL BOUNDARY PUSHING SOUTHWARD
THROUGH IL DURING THIS WEEKEND AS UPPER LEVEL RIDGE SHIFTS BACK
SOUTH AND WEAKENS. BEST CHANCES OF CONVECTION STILL APPEARS NORTH
OF CENTRAL IL FRIDAY AND THIS SHIFTS SOUTHWARD INTO CENTRAL IL SAT
AND BEST CHANCES SHIFT INTO SOUTHEAST IL BY SUNDAY. TEMPS TO
GRADUALLY COOL OFF CURING THE WEEKEND WITH HIGHS IN THE LOW TO MID
80S SUNDAY BUT STAYING RATHER HUMID YET WITH DEWPOINTS IN THE
UPPER 60S AND LOWER 70S.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1007 AM CDT SUN JUL 14 2013
.DISCUSSION...
ISSUED 1007 AM CDT SUN JUL 14 2013
NO CHANGES ANTICIPATED TO THE CURRENT FORECAST. UPPER LOW THAT
BROUGHT WIDELY SCATTERED THUNDERSTORMS TO SOUTHERN ILLINOIS
YESTERDAY HAS NOW SHIFTED INTO EASTERN KANSAS. SOUTHEASTERLY FLOW
ON ITS BACKSIDE IS BRINGING INCREASING MOISTURE INTO THE REGION
THIS MORNING...AS EVIDENCED BY UPSTREAM 850MB DEWPOINTS OF 13C AT
BOTH KILN AND KOHX. DESPITE LACK OF GOOD UPPER-LEVEL
SUPPORT...INCREASING MOISTURE AND POSSIBLE WEAKNESS/TROUGH AXIS IN
PRESSURE FIELD MAY SUPPORT ISOLATED CONVECTION LATER THIS
AFTERNOON. 13Z HRRR SHOWS THIS OCCURRING ACROSS MAINLY THE E/SE
KILX CWA AFTER 21Z. WILL CONTINUE TO MENTION ISOLATED THUNDER IN
THE FORECAST ACCORDINGLY...ALTHOUGH THE MAJORITY OF THE AREA WILL
REMAIN WARM AND DRY TODAY.
BARNES
&&
.AVIATION...
ISSUED 605 AM CDT SUN JUL 14 2013
SOME MVFR VSBYS IN FOG FOR A COUPLE OF HOURS EARLY AND AGAIN LATE
IN THIS FORECAST PERIOD...OTHERWISE...VFR CONDITIONS ARE EXPECTED.
THE UPPER LEVEL DISTURBANCE THAT PRODUCED THE CONVECTION JUST SOUTH
OF OUR TAF SITES LATE YESTERDAY HAS SHIFTED OFF TO OUR SOUTHWEST
THIS MORNING. A MOIST SOUTHEAST FLOW WILL PREVAIL ACRS THE AREA
TODAY WHICH WILL RESULT IN THE DEVELOPMENT OF A CU FIELD LATER
THIS MORNING WITH BASES BETWEEN 4500-5000 FEET. IT STILL APPEARS
ANY CONVECTION THAT DEVELOPS LATER THIS AFTERNOON WILL BE TOO
ISOLATED IN COVERAGE TO MENTION IN TAFS. CONVECTION CHANCES WANE
JUST AFTER SUNSET WITH THE PSBLTY OF SOME PATCHY FOG FORMING
AGAIN AFTR 06Z. SFC WINDS TODAY WILL BE FROM AN EAST TO SOUTHEAST
DIRECTION AT AROUND 10 KTS...AND FROM 5 TO 10 KTS TONIGHT.
SMITH
&&
.PREV DISCUSSION...
ISSUED 330 AM CDT SUN JUL 14 2013
SHORT TERM...TODAY THROUGH THURSDAY NIGHT
00Z MODELS ARE IN FAIR AGREEMENT THROUGH MID WEEK AS A HOT AND
HUMID WEEK IS AHEAD FOR CENTRAL AND SOUTHEAST IL. THIS DUE TO
STRONG 597 DM 500 MB HIGH PRESSURE RIDGE OFF THE SOUTHERN NEW
ENGLAND COAST INTO PA/NJ THAT RETROGRADES WESTWARD INTO THE OHIO
VALLEY AND SOUTHERN GREAT LAKES BY TUE AND STAYS NEAR IL AS IT
SLOWLY WEAKENS AND SHIFTS SOUTHWARD LATER THIS WEEK ALLOWING A
FRONTAL BOUNDARY TO SAG SOUTHWARD OVER THE REGION NEXT WEEKEND.
THIS BOUNDARY WILL BRING A BETTER CHANCE OF SHOWERS/THUNDERSTORMS
NEXT WEEKEND.
579 DM 500 MB LOW PRESSURE OVER SE MO MOVE QUICKLY WSW INTO
EASTERN OK BY SUNSET TODAY WHILE 597 DM 500 HIGH PRESSURE RIDGE
SHIFTS WESTWARD ACROSS PA AND INTO THE EASTERN GREAT LAKES REGION.
NOT MUCH LIFTING MECHISMS AROUND IL TODAY BUT INCREASING DEEPER
GULF MOISTURE CONTINUES TO STREAM NW INTO IL WITH PRECIPITABLE
WATER VALUES RISING TO 1.5 TO 2 INCHES THIS AFTERNOON AND HIGHEST
IN SE IL. AIRMASS GETS UNSTABLE THIS AFTERNOON WITH CAPES OF 1000
TO 2000 J/KG SE OF THE IL RIVER AND THIS SHOULD ALLOW ISOLATED
SHOWERS AND THUNDERSTORMS TO DEVELOP FROM MID AFTERNOON INTO EARLY
EVENING UNTIL SUNSET FROM I-72 SOUTH. SUNNY SKIES TO BECOME PARTLY
TO MOSTLY SUNNY IN AFTERNOON WITH HIGHS IN THE MID TO UPPER 80S.
DEWPOINTS IN THE LOW TO MID 60S TO RISE INTO THE UPPER 60S TO NEAR
70F BY AFTERNOON.
HAVE A SLIGHT CHANCE OF CONVECTION UNTIL MID EVENING FROM I-72
SOUTH THEN DRY REST OF TONIGHT WITH LOWS AROUND 70F. HAVE ISOLATED
CONVECTION DEVELOPING AGAIN DURING MONDAY AFTERNOON AND OVER IL
RIVER VALLEY TOO AS UNSTABLE AIRMASS SPREADS FURTHER NW. VERY WARM
AND HUMID WITH HIGHS IN THE UPPER 80S TO NEAR 90F MONDAY WITH
DEWPOINTS IN THE LOWER 70S. AFTERNOON HEAT INDICES IN MID TO UPPER
90S AND A FEW SPOTS IN SE IL BY WABASH RIVER NEARING 100F.
STRONG UPPER LEVEL RIDGE NEARS IL DURING MIDDLE OF THE WEEK
BRINGING HOT AND HUMID CONDITIONS WITH HIGHS IN THE LOWER 90S TUE
THROUGH FRI AND AFTERNOON HEAT INDICES OF 98 TO 105F. HAVE
ISOLATED CONVECTION POSSIBLE EACH AFTERNOON AND EARLY EVENING DURING
THE WORK WEEK AND COVERAGE SHOULD BE LIMITED WITH STRONG UPPER
LEVEL RIDGE NEARBY PROVIDING A CAP. BUT HAVE TROPICAL AIRMASS IN
PLACE WITH DEWPOINTS IN THE LOW TO MID 70S.
LONG TERM...FRIDAY THROUGH SUNDAY
MODELS HAVE TRENDED SLOWER WITH FRONTAL BOUNDARY PUSHING SOUTHWARD
THROUGH IL DURING THIS WEEKEND AS UPPER LEVEL RIDGE SHIFTS BACK
SOUTH AND WEAKENS. BEST CHANCES OF CONVECTION STILL APPEARS NORTH
OF CENTRAL IL FRIDAY AND THIS SHIFTS SOUTHWARD INTO CENTRAL IL SAT
AND BEST CHANCES SHIFT INTO SOUTHEAST IL BY SUNDAY. TEMPS TO
GRADUALLY COOL OFF CURING THE WEEKEND WITH HIGHS IN THE LOW TO MID
80S SUNDAY BUT STAYING RATHER HUMID YET WITH DEWPOINTS IN THE
UPPER 60S AND LOWER 70S.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
218 AM CDT SUN JUL 14 2013
.DISCUSSION...
903 PM CDT
CURRENT GRIDS/FORECAST IN GOOD SHAPE. MADE MINOR TWEAKS TO
TEMPS...DEW POINTS AND SKY GRIDS TO FIT CURRENT TRENDS. A FEW
PASSING CLOUDS FAR SOUTHERN PART OF FORECAST AREA ASSOCIATED WITH
WESTWARD MOVING UPPER LOW...OTHERWISE CLEAR SKIES EXPECTED THROUGH
THE OVERNIGHT. WITH LIGHT WINDS...SLOWLY INCREASING DEW POINTS AND
STAGNANT AIR MASS...SOME LIGHT HAZE CAN BE EXPECTED AROUND
SUNRISE...AWAY FROM THE CITY HEAT ISLAND...BUT NOT SIGNIFICANT
ENOUGH TO MENTION IN FORECAST AT THIS TIME.
ALLSOPP
//PREV DISCUSSION...
255 PM...MAIN FORECAST CONCERNS/CHALLENGES REMAIN RETURNING HEAT/
HUMIDITY AND CHANCES FOR PRIMARILY AFTERNOON THUNDERSTORMS.
IN THE SHORT TERM...AN UPPER LOW CONTINUES TO MOVE WEST ACROSS
THE OHIO VALLEY WITH THE BULK OF THE PRECIP ASSOCIATED WITH THIS
FEATURE WELL SOUTHEAST OF THE AREA AND EXPECT ANY PRECIP THAT
DOES DEVELOP ON THE NORTHERN SIDE OF THIS UPPER LOW TO REMAIN
SOUTH OF THE AREA TONIGHT. THIS ALSO PREVENTED THE CIRRUS FROM
EARLIER CONVECTION TO THE NORTHWEST FROM SPREADING ACROSS THE
AREA. WITH MOSTLY SUNNY SKIES...TEMPS HAVE CLIMBED INTO THE LOWER/
MID 80S...A LITTLE COOLER NEAR THE LAKE. DEWPOINTS DID DROP
DIURNALLY INTO THE 50S AND WILL TOUCH ON DEWPOINTS AGAIN FOR NEXT
WEEK. HOWEVER WITH LOW LEVEL MOISTURE GRADUALLY INCREASING...
APPEARS LOWS TONIGHT WILL ONLY DROP INTO THE LOWER/MID 60S AND
PROBABLY AROUND 70 IN CHICAGO.
A LARGE AREA OF HIGH PRESSURE EXTENDS FROM THE GREAT LAKES EAST
TO THE ATLANTIC AND THIS RIDGE WILL MOVE BACK WEST OVER THE NEXT
FEW DAYS...EVENTUALLY BECOMING CENTERED OVER THE OHIO VALLEY AND
SOUTHERN GREAT LAKES TUESDAY AND PERHAPS SLOWLY DRIFT SOUTH INTO
WEDNESDAY AND THURSDAY. THIS WILL CONTINUE TO ALLOW GENERALLY
LIGHT EASTERLY WINDS AND POTENTIAL LAKE BREEZES THROUGH TUESDAY
AFTERNOON...KEEPING THE LAKE SHORE AREAS A LITTLE COOLER. AND
WHILE THERE ARE NO SIGNIFICANT WAVES EXPECTED TO AFFECT THE
AREA...THE FORECAST SOUNDINGS DON/T SHOW MUCH CAPPING AND THUS
AS THE LOW LEVELS CONTINUE TO MOISTEN UP...ISOLATED THUNDERSTORMS
WILL REMAIN POSSIBLE MAINLY DURING THE AFTERNOON/EARLY EVENING
HOURS AND HAVE MAINTAINED SLIGHT CHANCE POPS MONDAY THROUGH
THURSDAY. HOWEVER...ITS POSSIBLE ISOLATED ACTIVITY COULD DEVELOP
SUNDAY AFTERNOON. IN ADDITION...AS THE HIGH NOW APPEARS TO DRIFT
SOUTH WEDNESDAY INTO THURSDAY...THERE IS INCREASING CONFIDENCE
THAT WINDS WILL TURN MORE WESTERLY DURING THIS TIME ALLOWING
WARMER AIR TO ADVECT INTO THE REGION WHICH WOULD LIKELY PROVIDE
ENOUGH CAPPING TO PREVENT CONVECTION. THUS WEDNESDAY AND THURSDAY
COULD END UP BEING DRY. A STRONG COLD FRONT IS STILL EXPECTED TO
MOVE SOUTH ACROSS THE REGION FRIDAY INTO FRIDAY NIGHT WITH THE GFS
FASTER THAN THE GEM/ECMWF. A SLOWER FRONTAL ARRIVAL WILL NOT JUST
DELAY PRECIP/POPS BUT ALSO COULD ALLOW FOR ANOTHER HOT/HUMID DAY
ON FRIDAY.
AS FOR TEMPS/DEWPOINTS...THERE REMAINS SEVERAL VARIABLES BUT
CONFIDENCE IS INCREASING. DEWPOINTS ARE EXPECTED TO SURGE BACK
INTO THE 70S BY MONDAY AND LIKELY REMAIN IN THE 70S UNTIL THE
FRONT ARRIVES FRIDAY/FRIDAY NIGHT. BUT AS SEEN OVER THE PAST
SEVERAL DAYS...DEWPOINTS CONTINUE TO MIX OUT OVER THE MORE URBAN
AREAS OF NORTHEAST IL AND LONGER TERM GUIDANCE HASN/T BEEN
HANDLING THIS TOO WELL...WHILE THE HIS RES HRRR HAS BEEN DOING
FAIRLY WELL THE PAST 2 DAYS. HAVE LOWERED DEWPOINTS INTO THE UPPER
60S DURING THE AFTERNOON ACROSS THE HEART OF THE METRO AREA BUT
CONFIDENCE REGARDING SPECIFIC TRENDS REMAINS LOW. BY WEDNESDAY AND
ESPECIALLY ON THURSDAY...EXPECT A LITTLE BIT MORE WESTERLY WINDS
AND DEEPER MIXING BUT MUCH OF THE LOW LEVELS REMAIN MOIST THUS
ITS POSSIBLE DEWPOINTS COULD HANG ON IN THE 70S EVERYWHERE. THESE
WILL BE KEY TO HEAT INDICES NOW THAT HIGH TEMPS IN THE LOWER 90S
LOOK REASONABLE AND HAVE BUMPED HIGH TEMPS UP A FEW DEGREES
MID/LATE WEEK. 12Z GEM/ECMWF ARE NOW IN THE +21C RANGE FOR 850MB
TEMPS THURSDAY WITH THE GFS SLIGHTLY COOLER BUT TRENDING WARMER
FROM PREVIOUS RUNS. ONLY HAVE HIGHS IN THE 92-93 RANGE BUT
DEPENDING ON HOW HIGH THE DEWPOINTS STAY...DEPTH OF MIXING AS
WELL AS CLOUD COVER...HIGHS ON THURSDAY COULD EASILY BE IN THE
MID 90S. AND DESPITE THE CONTINUED UNCERTAINTY REGARDING SPECIFIC
TEMPS/DEWPOINTS...EXPECT HEAT INDICES IN THE UPPER 90S/NEAR 100
ON TUESDAY AND THEN AROUND 100 FOR WEDNESDAY/THURSDAY.
WHILE ADVERTISED HIGHS ON FRIDAY ARE ONLY IN THE UPPER 80S DUE TO
THE UNCERTAINTY OF THE FRONTAL SPEED/TIMING...IF THE FRONT HOLDS
OFF UNTIL FRIDAY AFTERNOON OR EVENING...HIGHS COULD EASILY BE IN
THE LOWER/MID 90S AGAIN FRIDAY AND WHILE LOWS EVERY NIGHT WILL
LIKELY BE IN THE LOWER/MID 70S...THURSDAY NIGHT INTO FRIDAY
MORNING COULD BE PARTICULARLY WARM WITH LOWS MAYBE ONLY IN THE MID
TO UPPER 70S WITH PERHAPS ONLY 80 DOWNTOWN CHICAGO. BUT AS
MENTIONED ABOVE WHILE CONFIDENCE IS INCREASING WITH THE OVERALL
PATTERN/TRENDS...THIS IS STILL SEVERAL DAYS AWAY. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* NONE.
RATZER
//DISCUSSION...UPDATED 06Z...
VFR CONDITIONS WILL CONTINUE THROUGH THE TAF PERIOD...THOUGH SOME
MVFR HAZE IS POSSIBLE THROUGH SUNRISE MAINLY AT GYY/DPA/RFD AWAY
FROM WARMER CORE OF CHICAGO. PERSISTENT HIGH PRESSURE RIDGE WILL
AGAIN SUPPORT LIGHT WINDS...WITH A LAKE BREEZE PRODUCING EASTERLY
WINDS AROUND 10 KT WITH A FEW HIGHER GUSTS THIS AFTERNOON. SOME
MODEL GUIDANCE SUGGESTING ISOLATED SHRA/TSRA LATE THIS
AFTERNOON...THOUGH MODEL DEW POINT TEMPS AND RESULTING INSTABILITY
APPEAR OVERDONE AND NOT MUCH SUPPORT ALOFT WITH BUILDING UPPER
RIDGE.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE ALL FORECAST ELEMENTS.
RATZER
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY THROUGH THURSDAY...GENERALLY PREVAILING VFR...HOWEVER AN
AFTERNOON THUNDERSTORM CANNOT BE COMPLETELY RULED OUT ANY DAY.
FRIDAY...CHANCE OF THUNDERSTORMS.
IZZI
&&
.MARINE...
217 AM CDT
A PERIOD OF LIGHT WINDS WILL CONTINUE ACROSS LAKE MICHIGAN THROUGH
MONDAY NIGHT...AS THE WESTERN PERIPHERY OF AN ELONGATED AREA OF HIGH
PRESSURE RIDGE REMAINS ACROSS THE AREA. THE CENTER OF THE HIGH WAS
ACTUALLY OFF THE JERSEY SHORE EARLY THIS MORNING...BUT WILL DEVELOP
WEST INTO THE MID-ATLANTIC REGION TONIGHT AND ACROSS THE OHIO VALLEY
AND SOUTHERN GREAT LAKES REGION THROUGH MID-WEEK. A FAIRLY DEEP AREA
OF LOW PRESSURE WILL EVENTUALLY DEVELOP ACROSS NORTHERN MANITOBA
TUESDAY...INCREASING SOUTH-SOUTHWEST WINDS A BIT ACROSS LAKE
MICHIGAN...AND WILL MOVE NORTHEAST ACROSS HUDSON BAY AND INTO
NORTHERN QUEBEC BY THURSDAY. THIS LOW WILL TRAIL A COLD FRONT ACROSS
THE NORTHERN LAKES...WHICH WILL EVENTUALLY SETTLE ACROSS LAKE
MICHIGAN FRIDAY OR FRIDAY NIGHT. THUNDERSTORM CHANCES WILL INCREASE
MID-LATE WEEK AHEAD OF THIS FRONT.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1222 AM CDT SUN JUL 14 2013
.DISCUSSION...
903 PM CDT
CURRENT GRIDS/FORECAST IN GOOD SHAPE. MADE MINOR TWEAKS TO
TEMPS...DEW POINTS AND SKY GRIDS TO FIT CURRENT TRENDS. A FEW
PASSING CLOUDS FAR SOUTHERN PART OF FORECAST AREA ASSOCIATED WITH
WESTWARD MOVING UPPER LOW...OTHERWISE CLEAR SKIES EXPECTED THROUGH
THE OVERNIGHT. WITH LIGHT WINDS...SLOWLY INCREASING DEW POINTS AND
STAGNANT AIR MASS...SOME LIGHT HAZE CAN BE EXPECTED AROUND
SUNRISE...AWAY FROM THE CITY HEAT ISLAND...BUT NOT SIGNIFICANT
ENOUGH TO MENTION IN FORECAST AT THIS TIME.
ALLSOPP
//PREV DISCUSSION...
255 PM...MAIN FORECAST CONCERNS/CHALLENGES REMAIN RETURNING HEAT/
HUMIDITY AND CHANCES FOR PRIMARILY AFTERNOON THUNDERSTORMS.
IN THE SHORT TERM...AN UPPER LOW CONTINUES TO MOVE WEST ACROSS
THE OHIO VALLEY WITH THE BULK OF THE PRECIP ASSOCIATED WITH THIS
FEATURE WELL SOUTHEAST OF THE AREA AND EXPECT ANY PRECIP THAT
DOES DEVELOP ON THE NORTHERN SIDE OF THIS UPPER LOW TO REMAIN
SOUTH OF THE AREA TONIGHT. THIS ALSO PREVENTED THE CIRRUS FROM
EARLIER CONVECTION TO THE NORTHWEST FROM SPREADING ACROSS THE
AREA. WITH MOSTLY SUNNY SKIES...TEMPS HAVE CLIMBED INTO THE LOWER/
MID 80S...A LITTLE COOLER NEAR THE LAKE. DEWPOINTS DID DROP
DIURNALLY INTO THE 50S AND WILL TOUCH ON DEWPOINTS AGAIN FOR NEXT
WEEK. HOWEVER WITH LOW LEVEL MOISTURE GRADUALLY INCREASING...
APPEARS LOWS TONIGHT WILL ONLY DROP INTO THE LOWER/MID 60S AND
PROBABLY AROUND 70 IN CHICAGO.
A LARGE AREA OF HIGH PRESSURE EXTENDS FROM THE GREAT LAKES EAST
TO THE ATLANTIC AND THIS RIDGE WILL MOVE BACK WEST OVER THE NEXT
FEW DAYS...EVENTUALLY BECOMING CENTERED OVER THE OHIO VALLEY AND
SOUTHERN GREAT LAKES TUESDAY AND PERHAPS SLOWLY DRIFT SOUTH INTO
WEDNESDAY AND THURSDAY. THIS WILL CONTINUE TO ALLOW GENERALLY
LIGHT EASTERLY WINDS AND POTENTIAL LAKE BREEZES THROUGH TUESDAY
AFTERNOON...KEEPING THE LAKE SHORE AREAS A LITTLE COOLER. AND
WHILE THERE ARE NO SIGNIFICANT WAVES EXPECTED TO AFFECT THE
AREA...THE FORECAST SOUNDINGS DON/T SHOW MUCH CAPPING AND THUS
AS THE LOW LEVELS CONTINUE TO MOISTEN UP...ISOLATED THUNDERSTORMS
WILL REMAIN POSSIBLE MAINLY DURING THE AFTERNOON/EARLY EVENING
HOURS AND HAVE MAINTAINED SLIGHT CHANCE POPS MONDAY THROUGH
THURSDAY. HOWEVER...ITS POSSIBLE ISOLATED ACTIVITY COULD DEVELOP
SUNDAY AFTERNOON. IN ADDITION...AS THE HIGH NOW APPEARS TO DRIFT
SOUTH WEDNESDAY INTO THURSDAY...THERE IS INCREASING CONFIDENCE
THAT WINDS WILL TURN MORE WESTERLY DURING THIS TIME ALLOWING
WARMER AIR TO ADVECT INTO THE REGION WHICH WOULD LIKELY PROVIDE
ENOUGH CAPPING TO PREVENT CONVECTION. THUS WEDNESDAY AND THURSDAY
COULD END UP BEING DRY. A STRONG COLD FRONT IS STILL EXPECTED TO
MOVE SOUTH ACROSS THE REGION FRIDAY INTO FRIDAY NIGHT WITH THE GFS
FASTER THAN THE GEM/ECMWF. A SLOWER FRONTAL ARRIVAL WILL NOT JUST
DELAY PRECIP/POPS BUT ALSO COULD ALLOW FOR ANOTHER HOT/HUMID DAY
ON FRIDAY.
AS FOR TEMPS/DEWPOINTS...THERE REMAINS SEVERAL VARIABLES BUT
CONFIDENCE IS INCREASING. DEWPOINTS ARE EXPECTED TO SURGE BACK
INTO THE 70S BY MONDAY AND LIKELY REMAIN IN THE 70S UNTIL THE
FRONT ARRIVES FRIDAY/FRIDAY NIGHT. BUT AS SEEN OVER THE PAST
SEVERAL DAYS...DEWPOINTS CONTINUE TO MIX OUT OVER THE MORE URBAN
AREAS OF NORTHEAST IL AND LONGER TERM GUIDANCE HASN/T BEEN
HANDLING THIS TOO WELL...WHILE THE HIS RES HRRR HAS BEEN DOING
FAIRLY WELL THE PAST 2 DAYS. HAVE LOWERED DEWPOINTS INTO THE UPPER
60S DURING THE AFTERNOON ACROSS THE HEART OF THE METRO AREA BUT
CONFIDENCE REGARDING SPECIFIC TRENDS REMAINS LOW. BY WEDNESDAY AND
ESPECIALLY ON THURSDAY...EXPECT A LITTLE BIT MORE WESTERLY WINDS
AND DEEPER MIXING BUT MUCH OF THE LOW LEVELS REMAIN MOIST THUS
ITS POSSIBLE DEWPOINTS COULD HANG ON IN THE 70S EVERYWHERE. THESE
WILL BE KEY TO HEAT INDICES NOW THAT HIGH TEMPS IN THE LOWER 90S
LOOK REASONABLE AND HAVE BUMPED HIGH TEMPS UP A FEW DEGREES
MID/LATE WEEK. 12Z GEM/ECMWF ARE NOW IN THE +21C RANGE FOR 850MB
TEMPS THURSDAY WITH THE GFS SLIGHTLY COOLER BUT TRENDING WARMER
FROM PREVIOUS RUNS. ONLY HAVE HIGHS IN THE 92-93 RANGE BUT
DEPENDING ON HOW HIGH THE DEWPOINTS STAY...DEPTH OF MIXING AS
WELL AS CLOUD COVER...HIGHS ON THURSDAY COULD EASILY BE IN THE
MID 90S. AND DESPITE THE CONTINUED UNCERTAINTY REGARDING SPECIFIC
TEMPS/DEWPOINTS...EXPECT HEAT INDICES IN THE UPPER 90S/NEAR 100
ON TUESDAY AND THEN AROUND 100 FOR WEDNESDAY/THURSDAY.
WHILE ADVERTISED HIGHS ON FRIDAY ARE ONLY IN THE UPPER 80S DUE TO
THE UNCERTAINTY OF THE FRONTAL SPEED/TIMING...IF THE FRONT HOLDS
OFF UNTIL FRIDAY AFTERNOON OR EVENING...HIGHS COULD EASILY BE IN
THE LOWER/MID 90S AGAIN FRIDAY AND WHILE LOWS EVERY NIGHT WILL
LIKELY BE IN THE LOWER/MID 70S...THURSDAY NIGHT INTO FRIDAY
MORNING COULD BE PARTICULARLY WARM WITH LOWS MAYBE ONLY IN THE MID
TO UPPER 70S WITH PERHAPS ONLY 80 DOWNTOWN CHICAGO. BUT AS
MENTIONED ABOVE WHILE CONFIDENCE IS INCREASING WITH THE OVERALL
PATTERN/TRENDS...THIS IS STILL SEVERAL DAYS AWAY. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* NONE.
RATZER
//DISCUSSION...UPDATED 06Z...
VFR CONDITIONS WILL CONTINUE THROUGH THE TAF PERIOD...THOUGH SOME
MVFR HAZE IS POSSIBLE THROUGH SUNRISE MAINLY AT GYY/DPA/RFD AWAY
FROM WARMER CORE OF CHICAGO. PERSISTENT HIGH PRESSURE RIDGE WILL
AGAIN SUPPORT LIGHT WINDS...WITH A LAKE BREEZE PRODUCING EASTERLY
WINDS AROUND 10 KT WITH A FEW HIGHER GUSTS THIS AFTERNOON. SOME
MODEL GUIDANCE SUGGESTING ISOLATED SHRA/TSRA LATE THIS
AFTERNOON...THOUGH MODEL DEW POINT TEMPS AND RESULTING INSTABILITY
APPEAR OVERDONE AND NOT MUCH SUPPORT ALOFT WITH BUILDING UPPER
RIDGE.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE ALL FORECAST ELEMENTS.
RATZER
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY THROUGH THURSDAY...GENERALLY PREVAILING VFR...HOWEVER AN
AFTERNOON THUNDERSTORM CANNOT BE COMPLETELY RULED OUT ANY DAY.
FRIDAY...CHANCE OF THUNDERSTORMS.
IZZI
&&
.MARINE...
155 PM CDT
A SURFACE RIDGE OF HIGH PRESSURE CONTINUES TO DOMINATE ACROSS MUCH
OF THE GREAT LAKES. THIS HAS SET UP A FLOW PATTERN DRIVEN MAINLY BY
A LAKE BREEZE ACROSS THE SOUTHERN HALF OF THE LAKE...WHICH HAS
RESULTED IN LIGHT BUT ONSHORE FLOW. MEANWHILE FARTHER NORTH...A
SLIGHTLY BETTER GRADIENT ALONG THE NORTHWESTERN PERIPHERY OF THE
SURFACE RIDGE CONTINUES TO DRIVE SOUTHERLY WINDS UP TO 15 KT. THIS
GENERAL PATTERN WILL BE THE RULE DURING THE DAYTIME AGAIN ON SUNDAY
AND INTO MONDAY AS THE HIGH PRESSURE RIDGE CONTINUES TO INFLUENCE
THE LAKE.
THE FLOW SHOULD GRADUALLY BECOME MORE SOUTHWEST BY THE MIDDLE OF
NEXT WEEK AS THE SURFACE HIGH SHIFTS TO THE SOUTH AND WEST ACROSS
THE MID MISSISSIPPI AND OHIO VALLEYS AS A COUPLE OF LOWS TRACK
EASTWARD ACROSS ONTARIO. LATER NEXT WEEK...IT APPEARS THAT THE
WEATHER COULD BECOME ACTIVE ACROSS THE LAKE AS A COLD FRONT LOOKS TO
SHIFT SOUTHWARD DOWN THE LAKE. THIS COULD RESULT IN VERY GOOD
CHANCES FOR SHOWERS AND THUNDERSTORMS LATER NEXT WEEK.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS GOODLAND KS
557 PM MDT MON JUL 15 2013
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 138 PM MDT MON JUL 15 2013
LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOW 581 DM CLOSED LOW
CENTERED OVER SW OKLAHOMA...WITH A 599 DM RIDGE ACROSS THE EASTERN
CONUS EXTENDING WEST ACROSS THE NORTHERN PLAINS. WV IMAGERY SHOWS
MOISTURE CONTINUING TO ROTATE AROUND EASTERN EXTEND OF CLOSED LOW
INTO SOUTHERN KS. RAP/LATEST NAM SHOW A CURVED JET STRUCTURE ACROSS
THE NORTHERN PART OF CLOSED LOW OVER SW KS AND SEVERAL VORT MAXES
ROTATING THROUGH THE NORTHERN EXTENT OF THIS LOW. COMPOSITE RADAR
SHOWS SHOWER ACTIVITY HAVING DEVELOPED WITH THESE FEATURES MOVING TO
ACROSS CENTRAL AND SOUTHWEST KANSAS. VIS SATELLITE SHOWS A
WIDESPREAD CU FIELD IN PLACE ACROSS OUR CWA THAT HAS DEVELOPED WITH
DAYTIME HEATING AND COLD POOL ALOFT.
LATEST SHORT RANGE GUIDANCE SHOWS THE ACTIVITY CURRENTLY SOUTH AND
EAST OF THE CWA FALLING APART BY 00Z AS IT MOVES TOWARDS OUR CWA. AT
THIS POINT I AM NOT SURE WE WILL ACTUALLY SEE ANY SHOWERS DEVELOP
WITH CU FIELD...THOUGH UNTIL WE LOOSE DAYTIME HEATING I COULDNT RULE
OUT SHOWERS SPREADING INTO THE SOUTHERN HALF CONSIDERING RADAR
TRENDS...AND AT LEAST SOME LARGE SCALE FORCING STILL IN PLACE JUST TO
OUR SOUTH. I DO NOT EXPECT THIS TO BE WIDESPREAD AND SHOULD QUICKLY
END AS WE LOOSE FAVORABLE LOW LEVEL LAPSE RATES DUE TO DIURNAL
COOLING.
SOUTHERLY FLOW WILL KEEP BL MOISTURE IN PLACE OVERNIGHT AND
TUESDAY...AND THERE IS SOME INDICATION OF A FEW SHOWERS ACROSS
SOUTHERN KS...POSSIBLY INTO OUR CWA AS UPPER LOW CONTINUES TO SLOWLY
MOVE WEST. WITH LITTLE IN THE WAY OF INSTABILITY AND STRONG
SUBSIDENCE BUILDING IN FROM THE NORTH TONIGHT I DECIDED TO KEEP
FORECAST DRY. WE DO BEGIN TO SEE A SIMILAR SET UP AS THIS AFTERNOON
REGARDING INCREASING LAPSE RATES BELOW COLD POOL...HOWEVER WITH
RIDGE BEGINNING TO HOLD MORE INFLUENCE AND DRIER AIR MOVING INTO THE
REGION ALOFT...I DECIDED TO KEEP POPS SILENT FOR NOW. I DID KEEP
PATCHY FOG MENTION IN THE FORECAST FOR TUESDAY MORNING...AND GOOD BL
MOISTURE ADVECTING IN FROM THE SOUTH. WITH BL WINDS
INCREASING...IF WE SEE SURFACE WINDS AROUND 10KT THE LOW LEVELS
MAY BE TOO MIXED FOR FOG DEVELOPMENT...SO I KEPT COVERAGE PATCHY.
THERE IS LITTLE CHANGE REGARDING THE AIR MASS OVER OUR CWA
TUESDAY...AND THERE ARE SIMILAR TRENDS REGARDING CLOUD COVER. TEMPS
ON TUESDAY SHOULD BE VERY SIMILAR TO TODAY...WITH HIGHS RANGING FROM
THE UPPER 70S WEST TO UPPER 80S EAST.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 244 PM MDT MON JUL 15 2013
DRY CONDITIONS WITH A SLOW WARMING TREND WILL BE THE DOMINANT
WEATHER PATTERN UNTIL THE OF THE WEEK AS THE HIGH PRESSURE OVER THE
EASTERN CONUS MOVES WEST TOWARD THE ROCKIES. WEDNESDAY AND THURSDAY
WILL BE WINDY AS 850MB WINDS NEAR 30KTS ARE ABLE TO MIX DOWN TO
THE GROUND AHEAD OF THE RETROGRADING RIDGE. PRECIPITATION CHANCES
RETURN FRIDAY THROUGH EARLY NEXT WEEK AS A FEW UPPER LEVEL
DISTURBANCES MOVE THROUGH THE NORTHWEST FLOW OVER THE AREA.
FRIDAY A WEAK FRONT/SURFACE TROUGH MOVES OVER THE AREA...COOLING THE
ABOVE NORMAL TEMPERATURES DOWN AND HELPING WITH PRECIP. CHANCES AS
AN UPPER LEVEL TROUGH ALSO MOVES THROUGH.
THE WEAK FRONT LINGERS OVER THE SOUTHERN PART OF THE AREA THROUGH
SATURDAY WHICH MAY AID IN CREATING SOME STORMS FOR THE AREA.
PRECIPITATION CHANCES LINGER THROUGH EARLY NEXT WEAK AS ANOTHER WEAK
UPPER LEVEL TROUGH MOVES ACROSS THE AREA.
TEMPERATURES THROUGH THE PERIOD WILL START OUT NEAR NORMAL THEN WARM
TO NEAR/ABOVE NORMAL BY THE WEEKEND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 505 PM MDT MON JUL 15 2013
VFR CONDITIONS WILL PREVAIL FOR MOST OF THE TAF PERIOD WITH A SLIGHT
POSSIBILITY OF MVFR CONDITIONS IN THE MORNING DUE TO PATCHY FOG
WHICH MAY AFFECT BOTH TAF SITES. GUSTY SOUTHEAST WINDS WILL DIE
DOWN TONIGHT AND WILL PICK UP AGAIN TOMORROW MORNING/MIDDAY AROUND
15Z FOR KGLD AND 17Z FOR KMCK. WHILE SOUTHERLY WINDS ARE NOT THE
MOST FAVORABLE FOR FOG FORMATION...ENOUGH MOISTURE COULD BE
ADVECTED IN AT THE LOWER LEVELS THAT FOG COULD FORM OVER KGLD IN
THE MORNING. KMCK COULD ALSO SEE FOG DUE TO THE WINDS GOING LIGHT
COMBINED WITH MOISTURE FROM RECENT RAINFALL. INCLUDED A TEMPO
GROUP FOR REDUCED VISIBILITY OF 3SM FOR BOTH TAF SITES TO ACCOUNT
FOR THIS...ALTHOUGH CONFIDENCE IS A LITTLE LOW CONSIDERING THAT
THIS IS NOT FAVORED BY THE CLIMATOLOGY. THE LATER TAF ISSUANCES
MAY HAVE A BETTER HANDLE ON THIS SITUATION.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JTL
AVIATION...ALW
AREA FORECAST DISCUSSION
NWS GOODLAND KS
203 PM MDT SUN JUL 14 2013
.SHORT TERM...(THIS AFTERNOON THROUGH TONIGHT)
ISSUED AT 125 PM MDT SUN JUL 14 2013
LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOWS 579DM CLOSED LOW CENTERED
OVER NORTHEAST OKLAHOMA WITH STRONG PV HEIGHT ANOMALY IN PLACE OVER
SOUTHEAST KS. A 599DM RIDGE IS IN PLACE OVER THE NORTHEAST US WITH
AXIS EXTENDING NORTH OF CLOSED LOW INTO THE UPPER MISSISSIPPI VALLEY.
WITH GOOD MOISTURE/INSTABILITY IN PLACE AND SEVERAL WEAK CONVERGENT
AREAS WE ARE ALREADY SEEING THUNDERSTORMS DEVELOPING ALONG SEVERAL
WEAK CONVERGENT AREAS IN OUR CWA. AS LARGE SCALE FORCING INCREASES
AND THE MAIN MOISTURE PLUME MOVES OVER OUR CWA I EXPECT THUNDERSTORM
COVERAGE TO INCREASE. WHAT COULD BE DESCRIBED AS A COLD FRONT WILL
MOVE INTO THE CWA FROM THE SOUTHEAST THIS AFTERNOON AHEAD OF COLD
POOL ASSOCIATED WITH STRONG UPPER LOW. THUNDERSTORMS WILL INCREASE
IN COVERAGE AS THIS BOUNDARY MOVES NORTHWEST WITH BEST FORCING
CURRENTLY ADVERTISED IN THE 21-00Z TIME FRAME ALONG THE KS/CO BORDER
WHERE MOST GUIDANCE IS SHOWING VERY HIGH QPF VALUES. LATEST GFS IS A
LITTLE FURTHER EAST...HOWEVER SHORT RANGE GUIDANCE (RUC/HRRR)
CONTINUE TO SUPPORT THE NAM SOLUTION FURTHER WEST ALONG COLORADO
STATE LINE.
A VERY MOIST AIR MASS IS IN PLACE OVER THE CWA WITH LATEST RAP
ANALYSIS INDICATING PWAT VALUES IN EXCESS OF 1.5 INCHES AND AS HIGH
AS 1.8 INCHES IN NORTHEAST PARTS OF THE CWA. WHILE NOT UNHEARD OF
THIS IS ANOMALOUSLY HIGH FOR THIS TIME OF YEAR. SB/ML CAPE VALUES
HAVE INCREASED TO NEAR 2000 J/KG ACROSS THE NORTHEAST CWA AND THE
MAIN INSTABILITY AXIS SHOULD CONTINUE TO SPREAD SOUTH AND WEST THIS
AFTERNOON. SHEAR PROFILES ARE VERY WEAK...SO ANY SEVERE THREAT SHOULD
BE TIED TO WIND/HAIL ASSOCIATED WITH PULSE TYPE THUNDERSTORMS. STORM
MOTION WILL GENERALLY BE IN THE 5-15KT RANGE ACROSS THE AREA AND
THERE WILL BE THE POTENTIAL FOR BACK BUILDING AND SLOW PROPAGATION
ALONG THE BOUNDARY OVER OUR WESTERN CWA. WITH HIGH PRECIP RATES AND
SLOW MOVING (POSSIBLY TRAINING) THUNDERSTORM WE COULD SEE AN
ELEVATED THREAT FOR FLASH FLOODING. DESPITE OVERALL SHOWER AND
THUNDERSTORM COVERAGE LIKELY HIGH I AM NOT CONFIDENT THE FLASH FLOOD
THREAT WILL BE WIDESPREAD ENOUGH TO ISSUE A WATCH AT THIS TIME.
ACTIVITY SHOULD COME TO AN END QUICKLY FROM THE EAST TO THE WEST
THIS EVENING AS STRONG SUBSIDENCE BUILDS IN FROM THE NORTHEAST
ASSOCIATED WITH RIDGE BUILDING EAST BEHIND TROUGH. WITH LINGERING
CONVERGENCE ACROSS EASTERN COLORADO AND MOIST UPSLOPE WE COULD SEE A
FEW LINGERING SHOWERS/THUNDERSTORMS THROUGH 12Z WITH PATCHY FOG
POSSIBLY DEVELOPING IN THE 09Z-12Z TIME FRAME.
.LONG TERM...(MONDAY THROUGH SUNDAY)
ISSUED AT 158 PM MDT SUN JUL 14 2013
MONDAY MORNING MAY START OUT WITH SOME FOG OVER THE SOUTHERN AND
WESTERN PARTS OF THE AREA. ANY FOG THAT DEVELOPS SHOULD CLEAR OUT
BY MID MORNING. THE UPPER LEVEL LOW PRESSURE THAT BROUGHT RAINFALL
TO THE TRI-STATE AREA WILL CONTINUE TO MOVE SOUTH. LATE MONDAY
AFTERNOON INTO EARLY MONDAY EVENING THERE WILL BE A BAND OF MID
LEVEL LIFT THAT WILL MOVE ACROSS THE FAR SOUTHERN PART OF THE AREA.
THERE WILL BE AMBLE MOISTURE TO WORK...BUT THE LIMITING FACTOR WILL
BE THE STRENGTHEN OF THE LIFT AND THE SMALL AMOUNT OF INSTABILITY
AVAILABLE. AT THIS TIME THERE APPEARS TO BE ENOUGH LIFT AND
INSTABILITY THAT AN ISOLATED STORM CANNOT BE RULED OUT...SO WILL
KEEP THE SLIGHT CHANCES IN THE FORECAST BUT CONFINE THEM TO THE LATE
AFTERNOON AND EARLY EVENING.
TUESDAY AN UPPER LEVEL RIDGE BEGINS BUILDING OVER THE AREA.
SOUNDINGS OVER EAST CENTRAL COLORADO SHOW SOME INSTABILITY TO WORK
WITH AND LITTLE CIHN DURING THE AFTERNOON...BUT WITH NO SURFACE
CONVERGENCE OR UPPER LEVEL LIFT TO TRIGGER STORMS WILL KEEP THE DAY
DRY.
WEDNESDAY THROUGH SUNDAY AN UPPER LEVEL RIDGE WILL MOVE OVER THE
PLAINS THEN BECOME ESTABLISHED OVER THE ROCKIES. TOWARD THE END OF
THE WEEK THE UPPER LEVEL FLOW WILL STRENGTHEN AND BECOME NORTHWEST.
MODELS HAVE FLATTENED OUT THE SHORT WAVE TROUGH THAT WOULD MOVE OVER
THE AREA DURING THE WEEKEND. THE STRENGTH OF THE COLD FRONT HAS
ALSO DECREASED...WITH MODELS WASHING IT OUT ON SATURDAY OVER THE
AREA. HOWEVER MODELS STILL HAVE A SURFACE TROUGH/WEAK COLD FRONT
OVER THE AREA FOR THE WEEKEND. WITH NORTHWEST UPPER LEVEL FLOW OVER
THE AREA THERE IS STILL A POSSIBILITY FOR STORMS TO
DEVELOP...ALTHOUGH NOT AS GOOD AS PREVIOUSLY THOUGHT.
HIGH TEMPERATURES FOR THE PERIOD WILL GRADUALLY WARM TO ABOVE NORMAL
BY THE END OF THE WEEK AS THE UPPER LEVEL RIDGE BUILDS OVER THE
AREA. WITH LITTLE CHANGE IN THE AIR MASS BY THE END OF THE
WEEK...HIGHS WILL LARGELY REMAIN UNCHANGED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1123 AM MDT SUN JUL 14 2013
AS UPPER LEVEL SYSTEM MOVE WEST AND FORCING INCREASING
THUNDERSTORMS WILL INCREASE IN COVERAGE WITH BEST CHANCES AT KGLD
TERMINAL. HEAVY RAIN COULD DECREASE VIS TO IFR/MVFR CATEGORIES AT
KGLD...HOWEVER AXIS OF HEAVIEST RAIN MAY BE FURTHER WEST AND
CONFIDENCE WASNT THERE TO LOWER CONDITIONS BELOW VFR AT EITHER
TERMINAL. THUNDERSTORM ACTIVITY SHOULD TRANSITION WESTWARD WITH
HIGH PRESSURE BUILDING INT FROM THE NORTHEAST THIS EVENING. WINDS
ARE GOING TO BE ERRATIC EARLY IN THE PERIOD WITH SURFACE TROUGH
STILL IN PLACE...THOUGH EVENTUALLY THEY SHOULD SHIFT TO THE
NORTHEAST AND THEN SOUTHEAST AROUND 12KT AS FRONT MOVES OVER BOTH
TERMINALS THIS AFTERNOON.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JTL
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
126 PM MDT SUN JUL 14 2013
.SHORT TERM...(THIS AFTERNOON THROUGH TONIGHT)
ISSUED AT 125 PM MDT SUN JUL 14 2013
LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOWS 579DM CLOSED LOW CENTERED
OVER NORTHEAST OKLAHOMA WITH STRONG PV HEIGHT ANOMALY IN PLACE OVER
SOUTHEAST KS. A 599DM RIDGE IS IN PLACE OVER THE NORTHEAST US WITH
AXIS EXTENDING NORTH OF CLOSED LOW INTO THE UPPER MISSISSIPPI VALLEY.
WITH GOOD MOISTURE/INSTABILITY IN PLACE AND SEVERAL WEAK CONVERGENT
AREAS WE ARE ALREADY SEEING THUNDERSTORMS DEVELOPING ALONG SEVERAL
WEAK CONVERGENT AREAS IN OUR CWA. AS LARGE SCALE FORCING INCREASES
AND THE MAIN MOISTURE PLUME MOVES OVER OUR CWA I EXPECT THUNDERSTORM
COVERAGE TO INCREASE. WHAT COULD BE DESCRIBED AS A COLD FRONT WILL
MOVE INTO THE CWA FROM THE SOUTHEAST THIS AFTERNOON AHEAD OF COLD
POOL ASSOCIATED WITH STRONG UPPER LOW. THUNDERSTORMS WILL INCREASE
IN COVERAGE AS THIS BOUNDARY MOVES NORTHWEST WITH BEST FORCING
CURRENTLY ADVERTISED IN THE 21-00Z TIME FRAME ALONG THE KS/CO BORDER
WHERE MOST GUIDANCE IS SHOWING VERY HIGH QPF VALUES. LATEST GFS IS A
LITTLE FURTHER EAST...HOWEVER SHORT RANGE GUIDANCE (RUC/HRRR)
CONTINUE TO SUPPORT THE NAM SOLUTION FURTHER WEST ALONG COLORADO
STATE LINE.
A VERY MOIST AIRMASS IS IN PLACE OVER THE CWA WITH LATEST RAP
ANALYSIS INDICATING PWAT VALUES IN EXCESS OF 1.5 INCHES AND AS HIGH
AS 1.8 INCHES IN NORTHEAST PARTS OF THE CWA. WHILE NOT UNHEARD OF
THIS IS ANOMALOUSLY HIGH FOR THIS TIME OF YEAR. SB/ML CAPE VALUES
HAVE INCREASED TO NEAR 2000 J/KG ACROSS THE NORTHEAST CWA AND THE
MAIN INSTABILITY AXIS SHOULD CONTINUE TO SPREAD SOUTH AND WEST THIS
AFTERNOON. SHEAR PROFILES ARE VERY WEAK...SO ANY SEVERE THREAT SHOULD
BE TIED TO WIND/HAIL ASSOCIATED WITH PULSE TYPE THUNDERSTORMS. STORM
MOTION WILL GENERALLY BE IN THE 5-15KT RANGE ACROSS THE AREA AND
THERE WILL BE THE POTENTIAL FOR BACK BUILDING AND SLOW PROPAGATION
ALONG THE BOUNDARY OVER OUR WESTERN CWA. WITH HIGH PRECIP RATES AND
SLOW MOVING (POSSIBLY TRAINING) THUNDERSTORM WE COULD SEE AN
ELEVATED THREAT FOR FLASH FLOODING. DESPITE OVERALL SHOWER AND
THUNDERSTORM COVERAGE LIKELY HIGH I AM NOT CONFIDENT THE FLASH FLOOD
THREAT WILL BE WIDESPREAD ENOUGH TO ISSUE A WATCH AT THIS TIME.
ACTIVITY SHOULD COME TO AN END QUICKLY FROM THE EAST TO THE WEST
THIS EVENING AS STRONG SUBSIDENCE BUILDS IN FROM THE NORTHEAST
ASSOCIATED WITH RIDGE BUILDING EAST BEHIND TROUGH. WITH LINGERING
CONVERGENCE ACROSS EASTERN COLORADO AND MOIST UPSLOPE WE COULD SEE A
FEW LINGERING SHOWERS/THUNDERSTORMS THROUGH 12Z WITH PATCHY FOG
POSSIBLY DEVELOPING IN THE 09Z-12Z TIME FRAME.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 431 AM MDT SUN JUL 14 2013
SECOND HALF OF THE WORK WEEK LOOKS DRY AND WARMER AS A WEAK BUT
BROAD UPPER LEVEL RIDGE SITS ACROSS THE EASTERN TWO THIRDS OF THE
CONUS. BREEZY SOUTHERLY WINDS ON WED AND THURS WILL KEEP TEMPS AT OR
ABOVE NORMAL /LOW TO MID 90S/. NO PRECIP IS EXPECTED AND RELATIVE
HUMIDITY WILL REMAIN WELL ABOVE FIRE WX CRITERIA.
TOWARDS THE WEEKEND THE STORY CHANGES AS THE RIDGE IN THE EAST
BREAKS DOWN AND A SMALL BUT RELATIVELY STRONG VORT MAX MOVES ACROSS
NORTHERN COLORADO AND INTO THE CENTRAL HIGH PLAINS...THOUGH GUIDANCE
IS NOT IN VERY GOOD AGREEMENT ON THE PLACEMENT OF THE SYNOPTIC
FORCING. STILL...FEEL THERE IS GOOD ENOUGH AGREEMENT ON THIS AS AN
ASSOCIATED COLD FRONT COULD HELP WITH STORM DEVELOPMENT. MOISTURE
WILL BE NO PROBLEM AS SOUTH/SOUTHWESTERLY WINDS ALOFT WILL HELP TO
ADVECT MOIST MONSOONAL AIR INTO THE REGION...AND IN FACT ON SATURDAY
NIGHT GFS HAS PWATS OF OVER 1.50 INCHES. TEMPS WILL BE WARMEST ON
FRIDAY IN THE MID TO UPPER 90S...DROPPING TO UPPER 80S/LOW 90S ON
SATURDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1123 AM MDT SUN JUL 14 2013
AS UPPER LEVEL SYSTEM MOVE WEST AND FORCING INCREASING
THUNDERSTORMS WILL INCREASE IN COVERAGE WITH BEST CHANCES AT KGLD
TERMINAL. HEAVY RAIN COULD DECREASE VIS TO IFR/MVFR CATEGORIES AT
KGLD...HOWEVER AXIS OF HEAVIEST RAIN MAY BE FURTHER WEST AND
CONFIDENCE WASNT THERE TO LOWER CONDITIONS BELOW VFR AT EITHER
TERMINAL. THUNDERSTORM ACTIVITY SHOULD TRANSITION WESTWARD WITH
HIGH PRESSURE BUILDING INT FROM THE NORTHEAST THIS EVENING. WINDS
ARE GOING TO BE ERRATIC EARLY IN THE PERIOD WITH SURFACE TROUGH
STILL IN PLACE...THOUGH EVENTUALLY THEY SHOULD SHIFT TO THE
NORTHEAST AND THEN SOUTHEAST AROUND 12KT AS FRONT MOVES OVER BOTH
TERMINALS THIS AFTERNOON.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JJM
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1123 AM MDT SUN JUL 14 2013
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 431 AM MDT SUN JUL 14 2013
MAIN FORECAST CONCERNS WILL PRECIPITATION COVERAGE AND AMOUNTS
THROUGH TONIGHT IT WHAT LOOKS TO BE A COMPLICATED FORECAST DURING
THIS TIME. SATELLITE CONTINUING TO SHOW AN AMPLIFIED AND COMPLICATED
UPPER FLOW PATTERN FROM THE CENTRAL PACIFIC INTO EASTERN NORTH
AMERICA. EASTERLY WAVE/UPPER LOW IS PROGRESSING TOWARD THE AREA.
WEAK FLOW AND VERY MOIST AIR MASS IN PLACE ACROSS THE AREA AT THIS
TIME.
THERE WERE NO PROBLEMS AT JET LEVEL. THE GFS/UKMET WERE DOING A
LITTLE BETTER THAN THE CANADIAN AND SREF AT MID LEVELS. SREF AND
ECMWF WERE DOING BEST ON THE SYNOPTIC SCALE WIND/PRESSURE FIELD
OUTSIDE OF THE MASSIVE INFLUENCE OF ALL THE OUTFLOW BOUNDARIES. THE
GFS/UKMET/SREF DID THE BEST ON THE LOW LEVEL THERMAL FIELD ALTHOUGH
MODELS WERE CLOSE.
TODAY/TONIGHT...OVERNIGHT CONVECTION HAS BEEN SLOWLY WINDING DOWN
OVER THE AREA. NUMEROUS OUTFLOW BOUNDARIES ARE AROUND WITH A COUPLE
OF CONVECTIVE VORTICITY MAXES AROUND AS WELL. BAND OF SHOWERS AND
THUNDERSTORMS HAS DEVELOPED TO THE EAST OF THE AREA. INDIVIDUAL
CELLS ARE MOVING TOWARD THE SOUTH WITH THE AREA MOVING SLOWLY TOWARD
THE WEST. THIS LOOKS TO BE IN RESPONSE A TIGHTENING MID LEVEL
BAROCLINIC ZONE BETWEEN INCOMING UPPER LOW FROM THE EAST AND THE
UPPER RIDGE OVER US.
ONE CONVECTIVE VORTICITY MAX OR 700 MB CIRCULATION STARTS OUT THE
DAY ROUGHLY ALONG THE COLORADO AND KANSAS BORDER. THIS GETS PULLED
SOUTH AS INCOMING UPPER LOW GETS CLOSER. ALSO WHAT LOOKS TO BE
SEVERAL SHORTWAVE TROUGHS ROTATING AROUND PARENT UPPER LOW ARE
EVIDENT. WHAT MAKES ALL OF THIS INTERESTING IS THE PROGRESSION OF
FEATURES FROM EAST TO WEST TODAY. SURFACE CONVERGENCE SETS UP OVER
THE EASTERN PORTION OF THE AREA AND MOVES WEST WITH EAST TO
SOUTHEAST WINDS THEN SPREADING ACROSS THE AREA.
NAM12...HRRR AND RAP INDICATE A LULL IN PRECIPITATION ACTIVITY
THROUGH MID MORNING. CONSIDERING THE DECREASING TREND OF
PRECIPITATION THAT LOOKS REASONABLE. THEN HOW QUICKLY AND WHERE THE
MODELS PUT THE NEXT BATCH OF PRECIPITATION GETS A LITTLE MORE
UNCERTAIN. THE 06Z NAM AND GFS HAVE PULLED THE MAIN AXIS OF
DEVELOPING PRECIPITATION FURTHEST EAST WITH THE NAM THE FURTHEST
EAST OF NOT ONLY THE TWO BUT THE WHOLE MODEL SUITE. THE 00Z ECMWF
TRENDED IN THIS DIRECTION AS WELL. THE LATEST RAP AND HRRR WOULD
SUPPORT THE GUIDANCE WHICH HAS THE MAIN BAND OF PRECIPITATION
DEVELOPING ALONG AND A FEW COUNTIES TO THE EAST OF THE COLORADO
BORDER. CONSIDERING WHERE THE FRONT/SURFACE CONVERGENCE IS...THAT
LOCATION MAKES SENSE.
CURRENT GRIDS THAT WERE JUST ISSUED HAVE THE MAIN BAND ALONG AND TO
THE WEST. DO NOT FEEL CONFIDENT TO ADJUST THAT EVEN NOW. I DID PULL
THE LIKELYS FURTHER EAST AND INCREASED TO HIGHER LIKELYS AS WELL.
WILL BRIEF DAY SHIFT ON THIS TO MAKE ANY SLIGHT ADJUSTMENTS.
RAINFALL WILL PROGRESS TO THE WEST THROUGH THE NIGHT AND BE MOSTLY
DONE BY LATE EVENING. HOWEVER...IF HEAVIER RAIN STARTS FURTHER EAST
THEN THAT WILL HAVE TO BE CHANGED.
HAD EARLIER TOYED WITH THE IDEA OF A FLASH FLOOD WATCH DUE TO THE
HEAVIER RAIN LAST NIGHT. PWS ARE RATHER HIGH 1.5 TO NEARLY
2.0 INCHES. HOWEVER...HEAVIER RAINFALL AMOUNTS WERE SPOTTY AND NOT
WIDESPREAD...FFG IS STILL RATHER HIGH...STORM MOTIONS ARE SLOW BUT
NOT LESS THAN 10 MPH...AND SREF PROBABILITIES OF A HALF INCH TO ONE
INCH OF 6 HOUR RAINFALL ARE VERY LOW. STILL BELIEVE WILL GET
MODERATE TO HEAVY RAINFALL OVER THE WESTERN HALF PER THE PWS AND A
DEEP WARM LAYER IN THE SOUNDINGS.
LOWERED MAXES FOR THE DAY DUE TO EXPECTED CLOUD COVER...DEVELOPING
PRECIPITATION...AND EASTERLY WINDS/COLD AIR ADVECTION. HOWEVER...I
MAY NOT HAVE MADE THEM COOL ENOUGH. LATER TONIGHT THERE MAY BE A LOW
PROBABILITY OF FOG BUT DID NOT INCLUDE AT THIS TIME.
MONDAY/MONDAY NIGHT...DID NOT CHANGE THE GOING FORECAST MUCH
PRECIPITATION WISE. WITH THE POSITION OF THE UPPER LOW AND THE
UPPER RIDGE BUILDING IN FROM THE EAST...MAJORITY OF THE AREA WILL BE
DRY FOR THE ENTIRE PERIOD. THERE WILL BE A VERY LOW CHANCE IN THE
EXTREME SOUTH BUT THAT IS ABOUT IT. DETERMINISTIC AND GEFS
PROBABILITIES SUPPORT THIS. MADE ONLY SLIGHT ADJUSTMENTS TO THE
GOING MAX TEMPERATURE FORECAST WITH GUIDANCE IN DECENT AGREEMENT.
DID COOL OF THE FAR WEST AND SOUTHWEST.
TUESDAY/TUESDAY NIGHT...AREA REMAINS DRY AS MID/UPPER LEVEL RIDGE
BUILDS IN FROM THE EAST. SOUTHERLY SURFACE WINDS INCREASE AS WELL.
MODELS IN DECENT AGREEMENT WITH THE MAXES SO ONLY MADE SLIGHT
ADJUSTMENTS THERE.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 431 AM MDT SUN JUL 14 2013
SECOND HALF OF THE WORK WEEK LOOKS DRY AND WARMER AS A WEAK BUT
BROAD UPPER LEVEL RIDGE SITS ACROSS THE EASTERN TWO THIRDS OF THE
CONUS. BREEZY SOUTHERLY WINDS ON WED AND THURS WILL KEEP TEMPS AT OR
ABOVE NORMAL /LOW TO MID 90S/. NO PRECIP IS EXPECTED AND RELATIVE
HUMIDITY WILL REMAIN WELL ABOVE FIRE WX CRITERIA.
TOWARDS THE WEEKEND THE STORY CHANGES AS THE RIDGE IN THE EAST
BREAKS DOWN AND A SMALL BUT RELATIVELY STRONG VORT MAX MOVES ACROSS
NORTHERN COLORADO AND INTO THE CENTRAL HIGH PLAINS...THOUGH GUIDANCE
IS NOT IN VERY GOOD AGREEMENT ON THE PLACEMENT OF THE SYNOPTIC
FORCING. STILL...FEEL THERE IS GOOD ENOUGH AGREEMENT ON THIS AS AN
ASSOCIATED COLD FRONT COULD HELP WITH STORM DEVELOPMENT. MOISTURE
WILL BE NO PROBLEM AS SOUTH/SOUTHWESTERLY WINDS ALOFT WILL HELP TO
ADVECT MOIST MONSOONAL AIR INTO THE REGION...AND IN FACT ON SATURDAY
NIGHT GFS HAS PWATS OF OVER 1.50 INCHES. TEMPS WILL BE WARMEST ON
FRIDAY IN THE MID TO UPPER 90S...DROPPING TO UPPER 80S/LOW 90S ON
SATURDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1123 AM MDT SUN JUL 14 2013
AS UPPER LEVEL SYSTEM MOVE WEST AND FORCING INCREASING
THUNDERSTORMS WILL INCREASE IN COVERAGE WITH BEST CHANCES AT KGLD
TERMINAL. HEAVY RAIN COULD DECREASE VIS TO IFR/MVFR CATEGORIES AT
KGLD...HOWEVER AXIS OF HEAVIEST RAIN MAY BE FURTHER WEST AND
CONFIDENCE WASNT THERE TO LOWER CONDITIONS BELOW VFR AT EITHER
TERMINAL. THUNDERSTORM ACTIVITY SHOULD TRANSITION WESTWARD WITH
HIGH PRESSURE BUILDING INT FROM THE NORTHEAST THIS EVENING. WINDS
ARE GOING TO BE ERRATIC EARLY IN THE PERIOD WITH SURFACE TROUGH
STILL IN PLACE...THOUGH EVENTUALLY THEY SHOULD SHIFT TO THE
NORTHEAST AND THEN SOUTHEAST AROUND 12KT AS FRONT MOVES OVER BOTH
TERMINALS THIS AFTERNOON.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...JJM
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
543 AM MDT SUN JUL 14 2013
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 431 AM MDT SUN JUL 14 2013
MAIN FORECAST CONCERNS WILL PRECIPITATION COVERAGE AND AMOUNTS
THROUGH TONIGHT IT WHAT LOOKS TO BE A COMPLICATED FORECAST DURING
THIS TIME. SATELLITE CONTINUING TO SHOW AN AMPLIFIED AND COMPLICATED
UPPER FLOW PATTERN FROM THE CENTRAL PACIFIC INTO EASTERN NORTH
AMERICA. EASTERLY WAVE/UPPER LOW IS PROGRESSING TOWARD THE AREA.
WEAK FLOW AND VERY MOIST AIR MASS IN PLACE ACROSS THE AREA AT THIS
TIME.
THERE WERE NO PROBLEMS AT JET LEVEL. THE GFS/UKMET WERE DOING A
LITTLE BETTER THAN THE CANADIAN AND SREF AT MID LEVELS. SREF AND
ECMWF WERE DOING BEST ON THE SYNOPTIC SCALE WIND/PRESSURE FIELD
OUTSIDE OF THE MASSIVE INFLUENCE OF ALL THE OUTFLOW BOUNDARIES. THE
GFS/UKMET/SREF DID THE BEST ON THE LOW LEVEL THERMAL FIELD ALTHOUGH
MODELS WERE CLOSE.
TODAY/TONIGHT...OVERNIGHT CONVECTION HAS BEEN SLOWLY WINDING DOWN
OVER THE AREA. NUMEROUS OUTFLOW BOUNDARIES ARE AROUND WITH A COUPLE
OF CONVECTIVE VORTICITY MAXES AROUND AS WELL. BAND OF SHOWERS AND
THUNDERSTORMS HAS DEVELOPED TO THE EAST OF THE AREA. INDIVIDUAL
CELLS ARE MOVING TOWARD THE SOUTH WITH THE AREA MOVING SLOWLY TOWARD
THE WEST. THIS LOOKS TO BE IN RESPONSE A TIGHTENING MID LEVEL
BAROCLINIC ZONE BETWEEN INCOMING UPPER LOW FROM THE EAST AND THE
UPPER RIDGE OVER US.
ONE CONVECTIVE VORTICITY MAX OR 700 MB CIRCULATION STARTS OUT THE
DAY ROUGHLY ALONG THE COLORADO AND KANSAS BORDER. THIS GETS PULLED
SOUTH AS INCOMING UPPER LOW GETS CLOSER. ALSO WHAT LOOKS TO BE
SEVERAL SHORTWAVE TROUGHS ROTATING AROUND PARENT UPPER LOW ARE
EVIDENT. WHAT MAKES ALL OF THIS INTERESTING IS THE PROGRESSION OF
FEATURES FROM EAST TO WEST TODAY. SURFACE CONVERGENCE SETS UP OVER
THE EASTERN PORTION OF THE AREA AND MOVES WEST WITH EAST TO
SOUTHEAST WINDS THEN SPREADING ACROSS THE AREA.
NAM12...HRRR AND RAP INDICATE A LULL IN PRECIPITATION ACTIVITY
THROUGH MID MORNING. CONSIDERING THE DECREASING TREND OF
PRECIPITATION THAT LOOKS REASONABLE. THEN HOW QUICKLY AND WHERE THE
MODELS PUT THE NEXT BATCH OF PRECIPITATION GETS A LITTLE MORE
UNCERTAIN. THE 06Z NAM AND GFS HAVE PULLED THE MAIN AXIS OF
DEVELOPING PRECIPITATION FURTHEST EAST WITH THE NAM THE FURTHEST
EAST OF NOT ONLY THE TWO BUT THE WHOLE MODEL SUITE. THE 00Z ECMWF
TRENDED IN THIS DIRECTION AS WELL. THE LATEST RAP AND HRRR WOULD
SUPPORT THE GUIDANCE WHICH HAS THE MAIN BAND OF PRECIPITATION
DEVELOPING ALONG AND A FEW COUNTIES TO THE EAST OF THE COLORADO
BORDER. CONSIDERING WHERE THE FRONT/SURFACE CONVERGENCE IS...THAT
LOCATION MAKES SENSE.
CURRENT GRIDS THAT WERE JUST ISSUED HAVE THE MAIN BAND ALONG AND TO
THE WEST. DO NOT FEEL CONFIDENT TO ADJUST THAT EVEN NOW. I DID PULL
THE LIKELYS FURTHER EAST AND INCREASED TO HIGHER LIKELYS AS WELL.
WILL BRIEF DAY SHIFT ON THIS TO MAKE ANY SLIGHT ADJUSTMENTS.
RAINFALL WILL PROGRESS TO THE WEST THROUGH THE NIGHT AND BE MOSTLY
DONE BY LATE EVENING. HOWEVER...IF HEAVIER RAIN STARTS FURTHER EAST
THEN THAT WILL HAVE TO BE CHANGED.
HAD EARLIER TOYED WITH THE IDEA OF A FLASH FLOOD WATCH DUE TO THE
HEAVIER RAIN LAST NIGHT. PWS ARE RATHER HIGH 1.5 TO NEARLY
2.0 INCHES. HOWEVER...HEAVIER RAINFALL AMOUNTS WERE SPOTTY AND NOT
WIDESPREAD...FFG IS STILL RATHER HIGH...STORM MOTIONS ARE SLOW BUT
NOT LESS THAN 10 MPH...AND SREF PROBABILITIES OF A HALF INCH TO ONE
INCH OF 6 HOUR RAINFALL ARE VERY LOW. STILL BELIEVE WILL GET
MODERATE TO HEAVY RAINFALL OVER THE WESTERN HALF PER THE PWS AND A
DEEP WARM LAYER IN THE SOUNDINGS.
LOWERED MAXES FOR THE DAY DUE TO EXPECTED CLOUD COVER...DEVELOPING
PRECIPITATION...AND EASTERLY WINDS/COLD AIR ADVECTION. HOWEVER...I
MAY NOT HAVE MADE THEM COOL ENOUGH. LATER TONIGHT THERE MAY BE A LOW
PROBABILITY OF FOG BUT DID NOT INCLUDE AT THIS TIME.
MONDAY/MONDAY NIGHT...DID NOT CHANGE THE GOING FORECAST MUCH
PRECIPITATION WISE. WITH THE POSITION OF THE UPPER LOW AND THE
UPPER RIDGE BUILDING IN FROM THE EAST...MAJORITY OF THE AREA WILL BE
DRY FOR THE ENTIRE PERIOD. THERE WILL BE A VERY LOW CHANCE IN THE
EXTREME SOUTH BUT THAT IS ABOUT IT. DETERMINISTIC AND GEFS
PROBABILITIES SUPPORT THIS. MADE ONLY SLIGHT ADJUSTMENTS TO THE
GOING MAX TEMPERATURE FORECAST WITH GUIDANCE IN DECENT AGREEMENT.
DID COOL OF THE FAR WEST AND SOUTHWEST.
TUESDAY/TUESDAY NIGHT...AREA REMAINS DRY AS MID/UPPER LEVEL RIDGE
BUILDS IN FROM THE EAST. SOUTHERLY SURFACE WINDS INCREASE AS WELL.
MODELS IN DECENT AGREEMENT WITH THE MAXES SO ONLY MADE SLIGHT
ADJUSTMENTS THERE.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 431 AM MDT SUN JUL 14 2013
SECOND HALF OF THE WORK WEEK LOOKS DRY AND WARMER AS A WEAK BUT
BROAD UPPER LEVEL RIDGE SITS ACROSS THE EASTERN TWO THIRDS OF THE
CONUS. BREEZY SOUTHERLY WINDS ON WED AND THURS WILL KEEP TEMPS AT OR
ABOVE NORMAL /LOW TO MID 90S/. NO PRECIP IS EXPECTED AND RELATIVE
HUMIDITY WILL REMAIN WELL ABOVE FIRE WX CRITERIA.
TOWARDS THE WEEKEND THE STORY CHANGES AS THE RIDGE IN THE EAST
BREAKS DOWN AND A SMALL BUT RELATIVELY STRONG VORT MAX MOVES ACROSS
NORTHERN COLORADO AND INTO THE CENTRAL HIGH PLAINS...THOUGH GUIDANCE
IS NOT IN VERY GOOD AGREEMENT ON THE PLACEMENT OF THE SYNOPTIC
FORCING. STILL...FEEL THERE IS GOOD ENOUGH AGREEMENT ON THIS AS AN
ASSOCIATED COLD FRONT COULD HELP WITH STORM DEVELOPMENT. MOISTURE
WILL BE NO PROBLEM AS SOUTH/SOUTHWESTERLY WINDS ALOFT WILL HELP TO
ADVECT MOIST MONSOONAL AIR INTO THE REGION...AND IN FACT ON SATURDAY
NIGHT GFS HAS PWATS OF OVER 1.50 INCHES. TEMPS WILL BE WARMEST ON
FRIDAY IN THE MID TO UPPER 90S...DROPPING TO UPPER 80S/LOW 90S ON
SATURDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 539 AM MDT SUN JUL 14 2013
TRICKY/COMPLICATED SET OF TAFS. RARE SCENARIO TODAY THAT CONVECTION
THAT DEVELOPS WILL MOVE INTO THE AREA FROM THE NORTH AND EAST.
THERE LOOKS TO BE A LULL IN THE PRECIPITATION UNTIL THE MID TO
LATE MORNING WHEN PRECIPITATION IS EXPECTED TO DEVELOP. EXPECT THE
THUNDERSTORMS TO HAVE THE MOST AFFECT ON KGLD. DURING THE
AFTERNOON HOURS...THUNDERSTORMS COULD BRING CONDITIONS DOWN TO
MVFR OR JUST ABOVE IT. AFTER THAT FOR KGLD CONDITIONS SHOULD
IMPROVE. AT KMCK CHOSE TO HANDLE WITH A VCTS AT 18Z AT THIS TIME.
IT IS POSSIBLE THAT THUNDERSTORMS DEVELOP JUST TO THE WEST. LATER
TAFS WILL HAVE TO REFINE THE DETAILS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...JJM
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
431 AM MDT SUN JUL 14 2013
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 431 AM MDT SUN JUL 14 2013
MAIN FORECAST CONCERNS WILL PRECIPITATION COVERAGE AND AMOUNTS
THROUGH TONIGHT IT WHAT LOOKS TO BE A COMPLICATED FORECAST DURING
THIS TIME. SATELLITE CONTINUING TO SHOW AN AMPLIFIED AND COMPLICATED
UPPER FLOW PATTERN FROM THE CENTRAL PACIFIC INTO EASTERN NORTH
AMERICA. EASTERLY WAVE/UPPER LOW IS PROGRESSING TOWARD THE AREA.
WEAK FLOW AND VERY MOIST AIR MASS IN PLACE ACROSS THE AREA AT THIS
TIME.
THERE WERE NO PROBLEMS AT JET LEVEL. THE GFS/UKMET WERE DOING A
LITTLE BETTER THAN THE CANADIAN AND SREF AT MID LEVELS. SREF AND
ECMWF WERE DOING BEST ON THE SYNOPTIC SCALE WIND/PRESSURE FIELD
OUTSIDE OF THE MASSIVE INFLUENCE OF ALL THE OUTFLOW BOUNDARIES. THE
GFS/UKMET/SREF DID THE BEST ON THE LOW LEVEL THERMAL FIELD ALTHOUGH
MODELS WERE CLOSE.
TODAY/TONIGHT...OVERNIGHT CONVECTION HAS BEEN SLOWLY WINDING DOWN
OVER THE AREA. NUMEROUS OUTFLOW BOUNDARIES ARE AROUND WITH A COUPLE
OF CONVECTIVE VORTICITY MAXES AROUND AS WELL. BAND OF SHOWERS AND
THUNDERSTORMS HAS DEVELOPED TO THE EAST OF THE AREA. INDIVIDUAL
CELLS ARE MOVING TOWARD THE SOUTH WITH THE AREA MOVING SLOWLY TOWARD
THE WEST. THIS LOOKS TO BE IN RESPONSE A TIGHTENING MID LEVEL
BAROCLINIC ZONE BETWEEN INCOMING UPPER LOW FROM THE EAST AND THE
UPPER RIDGE OVER US.
ONE CONVECTIVE VORTICITY MAX OR 700 MB CIRCULATION STARTS OUT THE
DAY ROUGHLY ALONG THE COLORADO AND KANSAS BORDER. THIS GETS PULLED
SOUTH AS INCOMING UPPER LOW GETS CLOSER. ALSO WHAT LOOKS TO BE
SEVERAL SHORTWAVE TROUGHS ROTATING AROUND PARENT UPPER LOW ARE
EVIDENT. WHAT MAKES ALL OF THIS INTERESTING IS THE PROGRESSION OF
FEATURES FROM EAST TO WEST TODAY. SURFACE CONVERGENCE SETS UP OVER
THE EASTERN PORTION OF THE AREA AND MOVES WEST WITH EAST TO
SOUTHEAST WINDS THEN SPREADING ACROSS THE AREA.
NAM12...HRRR AND RAP INDICATE A LULL IN PRECIPITATION ACTIVITY
THROUGH MID MORNING. CONSIDERING THE DECREASING TREND OF
PRECIPITATION THAT LOOKS REASONABLE. THEN HOW QUICKLY AND WHERE THE
MODELS PUT THE NEXT BATCH OF PRECIPITATION GETS A LITTLE MORE
UNCERTAIN. THE 06Z NAM AND GFS HAVE PULLED THE MAIN AXIS OF
DEVELOPING PRECIPITATION FURTHEST EAST WITH THE NAM THE FURTHEST
EAST OF NOT ONLY THE TWO BUT THE WHOLE MODEL SUITE. THE 00Z ECMWF
TRENDED IN THIS DIRECTION AS WELL. THE LATEST RAP AND HRRR WOULD
SUPPORT THE GUIDANCE WHICH HAS THE MAIN BAND OF PRECIPITATION
DEVELOPING ALONG AND A FEW COUNTIES TO THE EAST OF THE COLORADO
BORDER. CONSIDERING WHERE THE FRONT/SURFACE CONVERGENCE IS...THAT
LOCATION MAKES SENSE.
CURRENT GRIDS THAT WERE JUST ISSUED HAVE THE MAIN BAND ALONG AND TO
THE WEST. DO NOT FEEL CONFIDENT TO ADJUST THAT EVEN NOW. I DID PULL
THE LIKELYS FURTHER EAST AND INCREASED TO HIGHER LIKELYS AS WELL.
WILL BRIEF DAY SHIFT ON THIS TO MAKE ANY SLIGHT ADJUSTMENTS.
RAINFALL WILL PROGRESS TO THE WEST THROUGH THE NIGHT AND BE MOSTLY
DONE BY LATE EVENING. HOWEVER...IF HEAVIER RAIN STARTS FURTHER EAST
THEN THAT WILL HAVE TO BE CHANGED.
HAD EARLIER TOYED WITH THE IDEA OF A FLASH FLOOD WATCH DUE TO THE
HEAVIER RAIN LAST NIGHT. PWS ARE RATHER HIGH 1.5 TO NEARLY
2.0 INCHES. HOWEVER...HEAVIER RAINFALL AMOUNTS WERE SPOTTY AND NOT
WIDESPREAD...FFG IS STILL RATHER HIGH...STORM MOTIONS ARE SLOW BUT
NOT LESS THAN 10 MPH...AND SREF PROBABILITIES OF A HALF INCH TO ONE
INCH OF 6 HOUR RAINFALL ARE VERY LOW. STILL BELIEVE WILL GET
MODERATE TO HEAVY RAINFALL OVER THE WESTERN HALF PER THE PWS AND A
DEEP WARM LAYER IN THE SOUNDINGS.
LOWERED MAXES FOR THE DAY DUE TO EXPECTED CLOUD COVER...DEVELOPING
PRECIPITATION...AND EASTERLY WINDS/COLD AIR ADVECTION. HOWEVER...I
MAY NOT HAVE MADE THEM COOL ENOUGH. LATER TONIGHT THERE MAY BE A LOW
PROBABILITY OF FOG BUT DID NOT INCLUDE AT THIS TIME.
MONDAY/MONDAY NIGHT...DID NOT CHANGE THE GOING FORECAST MUCH
PRECIPITATION WISE. WITH THE POSITION OF THE UPPER LOW AND THE
UPPER RIDGE BUILDING IN FROM THE EAST...MAJORITY OF THE AREA WILL BE
DRY FOR THE ENTIRE PERIOD. THERE WILL BE A VERY LOW CHANCE IN THE
EXTREME SOUTH BUT THAT IS ABOUT IT. DETERMINISTIC AND GEFS
PROBABILITIES SUPPORT THIS. MADE ONLY SLIGHT ADJUSTMENTS TO THE
GOING MAX TEMPERATURE FORECAST WITH GUIDANCE IN DECENT AGREEMENT.
DID COOL OF THE FAR WEST AND SOUTHWEST.
TUESDAY/TUESDAY NIGHT...AREA REMAINS DRY AS MID/UPPER LEVEL RIDGE
BUILDS IN FROM THE EAST. SOUTHERLY SURFACE WINDS INCREASE AS WELL.
MODELS IN DECENT AGREEMENT WITH THE MAXES SO ONLY MADE SLIGHT
ADJUSTMENTS THERE.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 431 AM MDT SUN JUL 14 2013
SECOND HALF OF THE WORK WEEK LOOKS DRY AND WARMER AS A WEAK BUT
BROAD UPPER LEVEL RIDGE SITS ACROSS THE EASTERN TWO THIRDS OF THE
CONUS. BREEZY SOUTHERLY WINDS ON WED AND THURS WILL KEEP TEMPS AT OR
ABOVE NORMAL /LOW TO MID 90S/. NO PRECIP IS EXPECTED AND RELATIVE
HUMIDITY WILL REMAIN WELL ABOVE FIRE WX CRITERIA.
TOWARDS THE WEEKEND THE STORY CHANGES AS THE RIDGE IN THE EAST
BREAKS DOWN AND A SMALL BUT RELATIVELY STRONG VORT MAX MOVES ACROSS
NORTHERN COLORADO AND INTO THE CENTRAL HIGH PLAINS...THOUGH GUIDANCE
IS NOT IN VERY GOOD AGREEMENT ON THE PLACEMENT OF THE SYNOPTIC
FORCING. STILL...FEEL THERE IS GOOD ENOUGH AGREEMENT ON THIS AS AN
ASSOCIATED COLD FRONT COULD HELP WITH STORM DEVELOPMENT. MOISTURE
WILL BE NO PROBLEM AS SOUTH/SOUTHWESTERLY WINDS ALOFT WILL HELP TO
ADVECT MOIST MONSOONAL AIR INTO THE REGION...AND IN FACT ON SATURDAY
NIGHT GFS HAS PWATS OF OVER 1.50 INCHES. TEMPS WILL BE WARMEST ON
FRIDAY IN THE MID TO UPPER 90S...DROPPING TO UPPER 80S/LOW 90S ON
SATURDAY.
&&
.AVIATION....(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1126 PM MDT SAT JUL 13 2013
VFR CONDITIONS EXPECTED AT BOTH KGLD AND KMCK THROUGH THE
OVERNIGHT HOURS...BUT FLIGHT CATEGORIES WILL BE LOWERING THROUGH
THE DAY ON SUNDAY WITH PRECIPITATION OVERSPREADING THE AREA.
OVERNIGHT...THERE ARE NUMEROUS OUTFLOW BOUNDARIES ASSOCIATED WITH
THUNDERSTORMS IN THE REGION...WIND DIRECTIONS MAY BE HIGHLY
VARIABLE THROUGH THE OVERNIGHT...AND CANNOT COMPLETELY RULE OUT A
BRIEF SHOWER OR THUNDERSTORM...BUT RECENT TRENDS SUGGESTS THEY
WILL NOT IMPACT EITHER TERMINAL FOR THE NEXT FEW HOURS.
SUNDAY...UNUSUAL PATTERN WITH AN UPPER LOW MOVING INTO OKLAHOMA
FROM THE EAST THIS AFTERNOON. PRECIPITATION WILL BE WRAPPING
AROUND THE SYSTEM FROM THE NORTH WITH RAIN AND EMBEDDED
THUNDERSTORMS DEVELOPING AS EARLY AS SUNDAY MORNING AND CONTINUING
THROUGH MOST OF THE DAY. CIGS WILL BE LOWERING AS WELL AS POSSIBLE
VISIBILITY RESTRICTIONS DUE TO RAIN AT BOTH KGLD AND KMCK.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...JJM
AVIATION...024
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1135 PM MDT SAT JUL 13 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 216 PM MDT SAT JUL 13 2013
LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOW 595DM RIDGE CENTERED OVER
TX/OK PANHANDLES WITH AXIS EXTENDING INTO THE NORTHERN PLAINS. A
CLOSED 578DM LOW OVER THE EASTERN OH RIVER VALLEY IS JUST DOWN
STREAM OF THIS FEATURE...WITH THE REMNANTS OF OVERNIGHT CONVECTION
IN THE NORTHERN PLAINS BEGINNING TO BECOME WRAPPED INTO THE FLOW
BETWEEN THESE FEATURES. A SHORTWAVE TROUGH IS CURRENTLY IN PLACE
OVER NE COLORADO...WITH THUNDERSTORMS ALREADY BEGINNING TO DEVELOP
OVER HIGHER TERRAIN IN ON WESTERN EXTENT OF THIS FEATURE. A SURFACE
TROUGH IS CURRENTLY CENTERED OVER THE NE PART OF OUR CWA AND EXTENDS
SOUTH AND WEST INTO SOUTHEAST COLORADO.
TD VALUES HAVE MIXED DOWN OVER EASTERN PARTS OF THE CWA...RESULTING
IN SLIGHTLY LOWER HEAT INDICES THAN ORIGINALLY ANTICIPATED. AT THE
SAME TIME CRITERIA IS BEING MET AT NORTON...AND WE HAVENT REACHED
PEAK HEATING YET...SO WILL PLAN ON LEAVING HEAT ADVISORY AS IS.
GUIDANCE CONTINUES TO SUPPORT THUNDERSTORMS INITIATING ALONG AND
BEHIND THE SURFACE TROUGH OVER OUR CWA...WITH BETTER COVERAGE CLOSER
TO H7/H5 SHORTWAVE TROUGH IN NORTHEAST COLORADO. LATEST RAP ANALYSIS
SHOWS AXIS OF 1500-2000 J/KG ML CAPE EXTENDING ACROSS CWA. SHEAR ISNT
VERY IMPRESSIVE...BUT WITH INVERTED V AND GOOD MOISTURE ABOVE DRY
LAYER STRONG GUSTS WILL BE A CONCERN WITH ANY THUNDERSTORMS.
GUIDANCE ACTUALLY SHOWS ACTIVITY CONTINUE THROUGH MOST OF THE
NIGHT...HOWEVER WITH SHORTWAVE WEAKENING AND MOVING NORTH AND EAST
IM LESS CONFIDENT IN THIS ACTIVITY LINGERING PAST 06Z.
CLOSED LOW OVER OH RIVER VALLEY WITH MOVE EAST INTO THE SOUTHERN
PLAINS SUNDAY WITH DEEP EASTERLY FLOW DEVELOPING ACROSS THE
CWA...AND COLD FRONT MOVING INTO THE REGION FROM THE SOUTHEAST LATE
IN THE AFTERNOON. BEST CONVERGENCE/LARGE SCALE ASCENT WILL LIKELY BE
ALONG FRONT RANGE EXTENDING INTO OUR EASTERN CO COUNTIES WHERE AXIS
OF STRONG VORTICITY ON NW QUAD OF UPPER LOW WILL COMBINE WITH STRONG
UPSLOPE TO PRODUCE SHOWERS AND THUNDERSTORMS. GUIDANCE CONTINUES TO
SHOW DECENT INSTABILITY IN PLACE...AND WITH PWATS IN EXCESS OF 1.5
INCHES WE COULD SEE NUMEROUS THUNDERSTORMS WITH HEAVY RAIN. I
TRENDED POPS UP DURING THE AFTERNOON TO LIKELY CATEGORY DURING
AFTERNOON.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 216 PM MDT SAT JUL 13 2013
SUNDAY EVENING THE FRONT WILL CONTINUE TO MOVE WEST...WITH THE
BEST INSTABILITY AND LIFT REMAINING OVER THE TROUGH. WITH LITTLE
CIHN TO HOLD BACK CONVECTION AND SURFACE CONVERGENCE SERVING AS A
TRIGGER...STORMS SHOULD NOT HAVE MUCH PROBLEM DEVELOPING. THE BEST
CHANCE FOR STORM DEVELOPMENT WILL BE OVER THE EAST CENTRAL
COLORADO AND PARTS OF FAR SOUTHWEST NEBRASKA WITH PRECIP. CHANCES
DECLINING TO THE EAST AS LIFT AND INSTABILITY TAPER OFF. AS THE
EVENING PROGRESSES THE SURFACE TROUGH WILL GRADUALLY MOVE WEST OUT
OF THE AREA...WITH BE BETTER PRECIP. CHANCES FOLLOWING IT.
MEANWHILE DRIER MORE STABLE AIR WILL BE MOVING IN FROM THE EAST
ACCOMPANYING AN INVERTED SURFACE RIDGE. THE DRIER AIR WILL HAVE
MOVED ACROSS ENTIRE AREA BY LATE IN THE NIGHT.
STRONG THUNDERSTORMS WILL BE POSSIBLE OVER THE NORTHWEST PART OF
THE AREA NEAR THE SURFACE TROUGH WHERE A CORRIDOR OF MIXED 1KM MOST
UNSTABLE CAPE IN EXCESS OF 2000J/KG WILL BE LOCATED. THE LIMITING
FACTOR WILL BE THE LOW 0-6KM SHEAR OF 15-20KTS...WHICH MAY BE
ENOUGH FOR AN ISOLATED SUPERCELL TO DEVELOP GIVEN THE ADEQUATE CAPE.
MEAN STORM MOTIONS WILL BE TO THE SOUTHEAST OVER EAST CENTRAL
COLORADO...SO THERE MAY BE SOME TRAINING ALONG THE SURFACE TROUGH
LEADING TO LOCALLY HEAVY RAINFALL IN THE EVENING.
MONDAY THE SURFACE RIDGE SLIDES SOUTH AS ANOTHER WAVE OF MOISTURE
MOVES OVER THE SOUTHERN HALF OF THE AREA AROUND THE UPPER LEVEL LOW
TO THE SOUTH DURING THE AFTERNOON. TOWARD LATE AFTERNOON A WAVE OF WEAK
LIFT DEVELOPS OVER THE FAR SOUTHERN PART OF THE AREA...THEN
DISSIPATES BY EARLY EVENING. THIS MAY BE ENOUGH LIFT FOR AN
ISOLATED STORM TO DEVELOP.
TUESDAY THROUGH SATURDAY WILL BE DRY FOR THE MAJORITY OF THE PERIOD
AS THE UPPER LEVEL RIDGE OVER THE EAST CONUS BUILDS WEST AND BECOMES
ESTABLISHED OVER THE WESTERN CONUS TOWARD THE END OF THE WORK WEEK.
DURING THE WEEKEND AN UPPER LEVEL SHORT WAVE TROUGH DEVELOPS OVER
THE NORTHERN ROCKIES AND MOVES SOUTHEAST OVER THE AREA. A COLD
FRONT WILL ACCOMPANY THE UPPER LEVEL FEATURE WHICH WILL AID THE LIFT
OF THE TROUGH. BEING A WEEK OUT THERE IS STILL A GOOD DEAL OF
UNCERTAINTY AS TO WHERE THE TROUGH WILL TRACK AND IF IT WILL BE DEEP
ENOUGH TO DEVELOP STORMS. WOULD NOT TAKE TOO MUCH OF A SHIFT IN THE
POSITION OF THE RIDGE OVER THE ROCKIES TO PUSH THE UPPER LEVEL
TROUGH NORTH OF THE AREA. AS SUCH WILL LEAVE PRECIP. CHANCES JUST
BELOW 50% FOR THE ENTIRE AREA FOR SATURDAY. HIGH TEMPERATURES FOR
THE PERIOD WILL GRADUALLY WARM AS THE RIDGE BUILDS EAST. NEAR
NORMAL VALUES THROUGH MID WEEK WILL WARM TO ABOVE NORMAL BY FRIDAY
WITH HIGHS RANGING FROM BELOW TO ABOVE NORMAL SATURDAY AS THE COLD
FRONT MOVES THROUGH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1126 PM MDT SAT JUL 13 2013
VFR CONDITIONS EXPECTED AT BOTH KGLD AND KMCK THROUGH THE
OVERNIGHT HOURS...BUT FLIGHT CATEGORIES WILL BE LOWERING THROUGH
THE DAY ON SUNDAY WITH PRECIPITATION OVERSPREADING THE AREA.
OVERNIGHT...THERE ARE NUMEROUS OUTFLOW BOUNDARIES ASSOCIATED WITH
THUNDERSTORMS IN THE REGION...WIND DIRECTIONS MAY BE HIGHLY
VARIABLE THROUGH THE OVERNIGHT...AND CANNOT COMPLETELY RULE OUT A
BRIEF SHOWER OR THUNDERSTORM...BUT RECENT TRENDS SUGGESTS THEY
WILL NOT IMPACT EITHER TERMINAL FOR THE NEXT FEW HOURS.
SUNDAY...UNUSUAL PATTERN WITH AN UPPER LOW MOVING INTO OKLAHOMA
FROM THE EAST THIS AFTERNOON. PRECIPITATION WILL BE WRAPPING
AROUND THE SYSTEM FROM THE NORTH WITH RAIN AND EMBEDDED
THUNDERSTORMS DEVELOPING AS EARLY AS SUNDAY MORNING AND CONTINUING
THROUGH MOST OF THE DAY. CIGS WILL BE LOWERING AS WELL AS POSSIBLE
VISIBILITY RESTRICTIONS DUE TO RAIN AT BOTH KGLD AND KMCK.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DJR
LONG TERM...JTL
AVIATION...024
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
103 PM EDT SUN JUL 14 2013
...Updated Aviation Discussion...
.FORECAST UPDATE...
Issued at 1200 PM EDT Sun Jul 14 2013
Deep southeasterly flow is in place across the Ohio Valley between
strong upper ridge building in from the mid Atlantic and the
retrograding upper low now over SW Missouri. Forecast is on track
for this afternoon, however have made a few small tweaks. So far,
any shower activity has struggled across the CWA as the deep
southeasterly component is downsloping off the Appalachians. This
component is also combining with a tongue of drier air evident on
water vapor imagery to limit showers as they move into east
Kentucky.
Still looks like the best coverage of showers or storms
(scattered) this afternoon will be across our SW CWA where deeper
moisture will reside and where downslope component is less
impactful. Still cannot rule out an isolated storm anywhere in the
CWA as full diurnal heating takes place, but think chances are low.
Have updated timing of afternoon showers/storms, but have not
changed coverages. Updated products already out.
&&
.SHORT TERM (Today through Monday)...
Issued at 300 AM EDT Sun Jul 14 2013
The short term period will continue the retrograding pattern with
the upper low now over southeastern Missouri moving west-southwest
to the southern Plains by tonight and Monday, as the upper high now
to our northeast expands westward into the Ohio Valley. In this
pattern, the best chance for convection will be today as a moisture
stream moves northwest between the upper low and high, with
suppressed chances on Monday.
In the near term, skies are clear to partly cloudy over central
Kentucky and southern Indiana, and this will hold through the
morning hours. Isolated showers early over parts of Larue and Hardin
counties have dissipated, and no more than an isolated shower or two
should still pop up elsewhere early this morning if at all. Patchy
fog could develop in a few river valleys by daybreak, otherwise
should not be much of a problem.
During the day today, the moisture stream in the short term models
shows precipitable water values of 1.5 to 2 inches with deep enough
moisture for scattered convective development this afternoon along
any mesoscale or cloud-clear type boundaries. It is difficult to pin
down at this time where cells might develop, although it appears
western parts of south-central Kentucky will have the best chance as
moisture streams up through the Tennessee Valley toward western
Kentucky. This would mean our northeastern counties might only see
isolated cells. This scenario is shown by the HRRR model, although
our in-house WRF develops scattered convection more over our
southeastern counties then propagates them northwest into north-
central Kentucky late this afternoon. Grids will reflect the HRRR,
which is supported by the NAM and GFS as well. In any storms, hail
should be less of a concern today than on Saturday given higher
temperatures aloft, although brief very heavy rain would be more
likely to occur along with CG lightning.
Any diurnal storms should die off this evening with a stabilizing
boundary layer. Skies should also become clear to partly cloudy
again. Patchy fog could develop late tonight in river valleys and
where any rain falls this afternoon.
On Monday, as the upper high builds in and heights and
temperatures aloft rise a bit, and as low-level moisture becomes a
little less prevalent, convection will be more hard pressed to
develop in the afternoon. As a result, while an isolated cell or two
could occur, the chances appear too small to include in the
forecast. Will go with a dry forecast under a partly cloudy sky.
High temperatures today should reach the upper 80s in many areas,
locally held down where showers occur. On Monday, highs should be
around 90 or the lower 90s in most areas, with maximum afternoon
heat indices in the mid to perhaps upper 90s.
.LONG TERM (Monday night through Saturday)...
Issued at 300 AM EDT Sun Jul 14 2013
Most of the upcoming week will degenerate into a broken record of a
forecast, as an anomalously strong upper ridge parks itself over the
Ohio Valley. Main sources of uncertainty center on convective
potential, and whether it will be the heat or the humidity making it
feel like close to 100 degrees each afternoon.
The atmosphere will be quite juicy with PWATs slightly above climo,
providing moderate to strong instability. Limiting factors will be
mid-level warming associated with the ridge, as H7 temps will run
10-11C, and the lack of any synoptic forcing. Convection will be
limited to diurnal activity, with probabilities below mentionable
thresholds in the north for much of the week. Highest POPs will be
in the low-end chance category, and confined to areas south of the
Western Kentucky and Bluegrass Parkways.
Temps are a bit of a crapshoot, as the moist ground is likely to
limit our warming at least in the first part of the week. Max temp
forecast undercuts extended GFS MOS by a few degrees, but still
expect to reach at least the lower 90s. Could see our heating catch
up with guidance later in the week as the heat dries out the ground.
Dewpoints in the lower 70s will push heat indices close to 100, but
any warmer temps will likely be offset by deeper mixing and slightly
lower dewpoints, so confidence is higher in the heat index forecast
than the actual temp or dewpoint forecast. Mins solidly above climo
in the lower to mid 70s each night.
POPs will increase as we head into the weekend, with a solid chance
on Saturday as the ridge starts to break down and we come under more
influence of the westerlies.
&&
.AVIATION (18Z TAF Update)...
Issued at 102 PM EDT Sun Jul 14 2013
Diurnally driven Cu around 3-4 k feet have started popping across
the region. This will continue through the afternoon, with chances
for scattered showers and storms at BWG. Have kept VCTS/CB groups in
at BWG. Confidence is not high enough in one of these showers/storms
impacting the terminal to go with predominant coverage, although a
storm would easily drop visibilities briefly to IFR. Will monitor
through the PM. Further northeast at SDF/LEX an isolated shower or
storm cannot be ruled out, however think coverage will be too sparse
to even mention VCTS at this time.
Otherwise, diurnally driven convection will diminish around sunset
this evening, with VFR conditions and a light SE wind continuing.
Could see some brief MVFR vis restrictions toward dawn at BWG.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Update...........BJS
Short Term.......TWF
Long Term........RAS
Aviation.........BJS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1200 PM EDT SUN JUL 14 2013
.FORECAST UPDATE...
Issued at 1200 PM EDT Sun Jul 14 2013
Deep southeasterly flow is in place across the Ohio Valley between
strong upper ridge building in from the mid Atlantic and the
retrograding upper low now over SW Missouri. Forecast is on track
for this afternoon, however have made a few small tweaks. So far,
any shower activity has struggled across the CWA as the deep
southeasterly component is downsloping off the Appalachians. This
component is also combining with a tongue of drier air evident on
water vapor imagery to limit showers as they move into east
Kentucky.
Still looks like the best coverage of showers or storms
(scattered) this afternoon will be across our SW CWA where deeper
moisture will reside and where downslope component is less
impactful. Still cannot rule out an isolated storm anywhere in the
CWA as full diurnal heating takes place, but think chances are low.
Have updated timing of afternoon showers/storms, but have not
changed coverages. Updated products already out.
&&
.SHORT TERM (Today through Monday)...
Issued at 300 AM EDT Sun Jul 14 2013
The short term period will continue the retrograding pattern with
the upper low now over southeastern Missouri moving west-southwest
to the southern Plains by tonight and Monday, as the upper high now
to our northeast expands westward into the Ohio Valley. In this
pattern, the best chance for convection will be today as a moisture
stream moves northwest between the upper low and high, with
suppressed chances on Monday.
In the near term, skies are clear to partly cloudy over central
Kentucky and southern Indiana, and this will hold through the
morning hours. Isolated showers early over parts of Larue and Hardin
counties have dissipated, and no more than an isolated shower or two
should still pop up elsewhere early this morning if at all. Patchy
fog could develop in a few river valleys by daybreak, otherwise
should not be much of a problem.
During the day today, the moisture stream in the short term models
shows precipitable water values of 1.5 to 2 inches with deep enough
moisture for scattered convective development this afternoon along
any mesoscale or cloud-clear type boundaries. It is difficult to pin
down at this time where cells might develop, although it appears
western parts of south-central Kentucky will have the best chance as
moisture streams up through the Tennessee Valley toward western
Kentucky. This would mean our northeastern counties might only see
isolated cells. This scenario is shown by the HRRR model, although
our in-house WRF develops scattered convection more over our
southeastern counties then propagates them northwest into north-
central Kentucky late this afternoon. Grids will reflect the HRRR,
which is supported by the NAM and GFS as well. In any storms, hail
should be less of a concern today than on Saturday given higher
temperatures aloft, although brief very heavy rain would be more
likely to occur along with CG lightning.
Any diurnal storms should die off this evening with a stabilizing
boundary layer. Skies should also become clear to partly cloudy
again. Patchy fog could develop late tonight in river valleys and
where any rain falls this afternoon.
On Monday, as the upper high builds in and heights and
temperatures aloft rise a bit, and as low-level moisture becomes a
little less prevalent, convection will be more hard pressed to
develop in the afternoon. As a result, while an isolated cell or two
could occur, the chances appear too small to include in the
forecast. Will go with a dry forecast under a partly cloudy sky.
High temperatures today should reach the upper 80s in many areas,
locally held down where showers occur. On Monday, highs should be
around 90 or the lower 90s in most areas, with maximum afternoon
heat indices in the mid to perhaps upper 90s.
.LONG TERM (Monday night through Saturday)...
Issued at 300 AM EDT Sun Jul 14 2013
Most of the upcoming week will degenerate into a broken record of a
forecast, as an anomalously strong upper ridge parks itself over the
Ohio Valley. Main sources of uncertainty center on convective
potential, and whether it will be the heat or the humidity making it
feel like close to 100 degrees each afternoon.
The atmosphere will be quite juicy with PWATs slightly above climo,
providing moderate to strong instability. Limiting factors will be
mid-level warming associated with the ridge, as H7 temps will run
10-11C, and the lack of any synoptic forcing. Convection will be
limited to diurnal activity, with probabilities below mentionable
thresholds in the north for much of the week. Highest POPs will be
in the low-end chance category, and confined to areas south of the
Western Kentucky and Bluegrass Parkways.
Temps are a bit of a crapshoot, as the moist ground is likely to
limit our warming at least in the first part of the week. Max temp
forecast undercuts extended GFS MOS by a few degrees, but still
expect to reach at least the lower 90s. Could see our heating catch
up with guidance later in the week as the heat dries out the ground.
Dewpoints in the lower 70s will push heat indices close to 100, but
any warmer temps will likely be offset by deeper mixing and slightly
lower dewpoints, so confidence is higher in the heat index forecast
than the actual temp or dewpoint forecast. Mins solidly above climo
in the lower to mid 70s each night.
POPs will increase as we head into the weekend, with a solid chance
on Saturday as the ridge starts to break down and we come under more
influence of the westerlies.
&&
.AVIATION (12Z TAF Update)...
Issued at 625 AM EDT Sun Jul 14 2013
Visibilities at BWG and LEX early this morning so far have remained
VFR, and this should continue through daylight hours this morning.
Otherwise, stream of mid-level clouds are moving northwest over
western KY, with clear to partly cloudy skies elsewhere over central
KY. Forecast remains on track for sct-to-bkn clouds around 4 kft or
so to develop by late morning or afternoon, along with some mid
clouds. Scattered afternoon thunderstorms expected in vicinity of
BWG with isolated for SDF and LEX. Conditions will remain VFR except
briefly lower if any convective cells impact the TAF site. Any cells
should weaken/dissipate around 00z or slightly thereafter, with VFR
conditions continuing Sunday night.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Update...........BJS
Short Term.......TWF
Long Term........RAS
Aviation.........TWF
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
631 AM EDT SUN JUL 14 2013
...Updated Aviation Discussion...
.SHORT TERM (Today through Monday)...
Issued at 300 AM EDT Sun Jul 14 2013
The short term period will continue the retrograding pattern with
the upper low now over southeastern Missouri moving west-southwest
to the southern Plains by tonight and Monday, as the upper high now
to our northeast expands westward into the Ohio Valley. In this
pattern, the best chance for convection will be today as a moisture
stream moves northwest between the upper low and high, with
suppressed chances on Monday.
In the near term, skies are clear to partly cloudy over central
Kentucky and southern Indiana, and this will hold through the
morning hours. Isolated showers early over parts of Larue and Hardin
counties have dissipated, and no more than an isolated shower or two
should still pop up elsewhere early this morning if at all. Patchy
fog could develop in a few river valleys by daybreak, otherwise
should not be much of a problem.
During the day today, the moisture stream in the short term models
shows precipitable water values of 1.5 to 2 inches with deep enough
moisture for scattered convective development this afternoon along
any mesoscale or cloud-clear type boundaries. It is difficult to pin
down at this time where cells might develop, although it appears
western parts of south-central Kentucky will have the best chance as
moisture streams up through the Tennessee Valley toward western
Kentucky. This would mean our northeastern counties might only see
isolated cells. This scenario is shown by the HRRR model, although
our in-house WRF develops scattered convection more over our
southeastern counties then propagates them northwest into north-
central Kentucky late this afternoon. Grids will reflect the HRRR,
which is supported by the NAM and GFS as well. In any storms, hail
should be less of a concern today than on Saturday given higher
temperatures aloft, although brief very heavy rain would be more
likely to occur along with CG lightning.
Any diurnal storms should die off this evening with a stabilizing
boundary layer. Skies should also become clear to partly cloudy
again. Patchy fog could develop late tonight in river valleys and
where any rain falls this afternoon.
On Monday, as the upper high builds in and heights and
temperatures aloft rise a bit, and as low-level moisture becomes a
little less prevalent, convection will be more hard pressed to
develop in the afternoon. As a result, while an isolated cell or two
could occur, the chances appear too small to include in the
forecast. Will go with a dry forecast under a partly cloudy sky.
High temperatures today should reach the upper 80s in many areas,
locally held down where showers occur. On Monday, highs should be
around 90 or the lower 90s in most areas, with maximum afternoon
heat indices in the mid to perhaps upper 90s.
.LONG TERM (Monday night through Saturday)...
Issued at 300 AM EDT Sun Jul 14 2013
Most of the upcoming week will degenerate into a broken record of a
forecast, as an anomalously strong upper ridge parks itself over the
Ohio Valley. Main sources of uncertainty center on convective
potential, and whether it will be the heat or the humidity making it
feel like close to 100 degrees each afternoon.
The atmosphere will be quite juicy with PWATs slightly above climo,
providing moderate to strong instability. Limiting factors will be
mid-level warming associated with the ridge, as H7 temps will run
10-11C, and the lack of any synoptic forcing. Convection will be
limited to diurnal activity, with probabilities below mentionable
thresholds in the north for much of the week. Highest POPs will be
in the low-end chance category, and confined to areas south of the
Western Kentucky and Bluegrass Parkways.
Temps are a bit of a crapshoot, as the moist ground is likely to
limit our warming at least in the first part of the week. Max temp
forecast undercuts extended GFS MOS by a few degrees, but still
expect to reach at least the lower 90s. Could see our heating catch
up with guidance later in the week as the heat dries out the ground.
Dewpoints in the lower 70s will push heat indices close to 100, but
any warmer temps will likely be offset by deeper mixing and slightly
lower dewpoints, so confidence is higher in the heat index forecast
than the actual temp or dewpoint forecast. Mins solidly above climo
in the lower to mid 70s each night.
POPs will increase as we head into the weekend, with a solid chance
on Saturday as the ridge starts to break down and we come under more
influence of the westerlies.
&&
.AVIATION (12Z TAF Update)...
Issued at 625 AM EDT Sun Jul 14 2013
Visibilities at BWG and LEX early this morning so far have remained
VFR, and this should continue through daylight hours this morning.
Otherwise, stream of mid-level clouds are moving northwest over
western KY, with clear to partly cloudy skies elsewhere over central
KY. Forecast remains on track for sct-to-bkn clouds around 4 kft or
so to develop by late morning or afternoon, along with some mid
clouds. Scattered afternoon thunderstorms expected in vicinity of
BWG with isolated for SDF and LEX. Conditions will remain VFR except
briefly lower if any convective cells impact the TAF site. Any cells
should weaken/dissipate around 00z or slightly thereafter, with VFR
conditions continuing Sunday night.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Short Term.......TWF
Long Term........RAS
Aviation.........TWF
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
315 AM EDT SUN JUL 14 2013
.SHORT TERM (Today through Monday)...
Issued at 300 AM EDT Sun Jul 14 2013
The short term period will continue the retrograding pattern with
the upper low now over southeastern Missouri moving west-southwest
to the southern Plains by tonight and Monday, as the upper high now
to our northeast expands westward into the Ohio Valley. In this
pattern, the best chance for convection will be today as a moisture
stream moves northwest between the upper low and high, with
suppressed chances on Monday.
In the near term, skies are clear to partly cloudy over central
Kentucky and southern Indiana, and this will hold through the
morning hours. Isolated showers early over parts of Larue and Hardin
counties have dissipated, and no more than an isolated shower or two
should still pop up elsewhere early this morning if at all. Patchy
fog could develop in a few river valleys by daybreak, otherwise
should not be much of a problem.
During the day today, the moisture stream in the short term models
shows precipitable water values of 1.5 to 2 inches with deep enough
moisture for scattered convective development this afternoon along
any mesoscale or cloud-clear type boundaries. It is difficult to pin
down at this time where cells might develop, although it appears
western parts of south-central Kentucky will have the best chance as
moisture streams up through the Tennessee Valley toward western
Kentucky. This would mean our northeastern counties might only see
isolated cells. This scenario is shown by the HRRR model, although
our in-house WRF develops scattered convection more over our
southeastern counties then propagates them northwest into north-
central Kentucky late this afternoon. Grids will reflect the HRRR,
which is supported by the NAM and GFS as well. In any storms, hail
should be less of a concern today than on Saturday given higher
temperatures aloft, although brief very heavy rain would be more
likely to occur along with CG lightning.
Any diurnal storms should die off this evening with a stabilizing
boundary layer. Skies should also become clear to partly cloudy
again. Patchy fog could develop late tonight in river valleys and
where any rain falls this afternoon.
On Monday, as the upper high builds in and heights and
temperatures aloft rise a bit, and as low-level moisture becomes a
little less prevalent, convection will be more hard pressed to
develop in the afternoon. As a result, while an isolated cell or two
could occur, the chances appear too small to include in the
forecast. Will go with a dry forecast under a partly cloudy sky.
High temperatures today should reach the upper 80s in many areas,
locally held down where showers occur. On Monday, highs should be
around 90 or the lower 90s in most areas, with maximum afternoon
heat indices in the mid to perhaps upper 90s.
.LONG TERM (Monday Night through Saturday)...
Issued at 300 AM EDT Sun Jul 14 2013
Most of the upcoming week will degenerate into a broken record of a
forecast, as an anomalously strong upper ridge parks itself over the
Ohio Valley. Main sources of uncertainty center on convective
potential, and whether it will be the heat or the humidity making it
feel like close to 100 degrees each afternoon.
The atmosphere will be quite juicy with PWATs slightly above climo,
providing moderate to strong instability. Limiting factors will be
mid-level warming associated with the ridge, as H7 temps will run
10-11C, and the lack of any synoptic forcing. Convection will be
limited to diurnal activity, with probabilities below mentionable
thresholds in the north for much of the week. Highest POPs will be
in the low-end chance category, and confined to areas south of the
Western Kentucky and Bluegrass Parkways.
Temps are a bit of a crapshoot, as the moist ground is likely to
limit our warming at least in the first part of the week. Max temp
forecast undercuts extended GFS MOS by a few degrees, but still
expect to reach at least the lower 90s. Could see our heating catch
up with guidance later in the week as the heat dries out the ground.
Dewpoints in the lower 70s will push heat indices close to 100, but
any warmer temps will likely be offset by deeper mixing and slightly
lower dewpoints, so confidence is higher in the heat index forecast
than the actual temp or dewpoint forecast. Mins solidly above climo
in the lower to mid 70s each night.
POPs will increase as we head into the weekend, with a solid chance
on Saturday as the ridge starts to break down and we come under more
influence of the westerlies.
&&
.AVIATION (06Z TAF Update)...
Issued at 120 AM EDT Sun Jul 14 2013
As the upper low moves westward into Missouri, low-to-mid-level
moisture continues to stream northwestward to its east. Isolated
showers are possible from 06-12z although should not affect any TAF
sites. With somewhat higher surface dewpoints and clear to partly
cloudy skies, there could be patchy fog around daybreak which could
affect BWG and/or LEX with possible MVFR conditions at times from
about 10-13z (will monitor any fog development). Otherwise,
sufficient moisture and instability should be present on Sunday for
isolated to scattered convective development, mainly in afternoon,
with BWG most susceptible and probably LEX least susceptible. Will
carry VCTS at each site. Conditions should be VFR on Sunday, except
briefly lower if a cell impacts the site. Any convective cells
should weaken/dissipate around 00z, with VFR conditions thereafter.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Short Term.......TWF
Long Term........RAS
Aviation.........TWF
AREA FORECAST DISCUSSION
NWS CARIBOU ME
110 PM EDT SUN JUL 14 2013
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN ACROSS THE REGION THROUGH EARLY NEXT
WEEK WHILE A WEAK COLD FRONT IS EXPECTED TO CROSS THE AREA ON
MONDAY. A STRONGER COLD FRONT WILL APPROACH FROM THE NORTHWEST
LATER WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
110 PM UPDATE...NO SIGNIFICANT CHANGES WERE NEEDED FOR THIS
UPDATE. ONLY MADE SOME TWEAKS TO SKY COVER AND MAX TEMPS TO MATCH
CURRENT SATELLITE AND SURFACE OBS TRENDS.
PREVIOUS DISCUSSION...CONTINUED WARM AND DRY THIS TERM. A LARGE
RIDGE OF HIGH PRES WILL REMAIN IN CONTROL W/ANOTHER DAY OF VERY
WARM TEMPERATURES.
LATEST SATL IR IMAGERY SHOWED SOME MID AND HIGH CLOUDS ROLLING
OVER THE UPPER RIDGE INTO PORTIONS OF NORTHERN AND EASTERN MAINE.
THE 00Z UA SHOWED A 50KT JETLET IN THE UPPER LEVELS ACROSS QUEBEC
AIDING IN THE CLOUDS PUSHING TOWARD THE CROWN OF MAINE. SOME STRATUS
AND FOG DEVELOPING OVER SWRN MAINE NEAR THE WATERVILLE AREA AND
ANOTHER BATCH SITTING OFF THE MAINE COAST. SATL LOOP SHOWED THIS
STRATUS AND FOG SLOWLY EDGING NORTHWARD TOWARD THE THE DOWNEAST
AND COAST. DECIDED TO ADD SOME PATCHY FOR THE INTERIOR DONWEAST
AND THE COAST. STRATUS AND FOG WILL LIFT AND BURN AFTER SUNRISE
THIS MORNING. THE LATEST HRRR AND LAMP GUIDANCE DOING QUITE WELL
W/THE TEMPERATURE PROFILE ATTM PER THE 06Z OBS AND HAVE LEANED
THIS WAY FOR THE DAYTIME HIGHS TODAY WHICH SHOWS UPPER 80S TO
AROUND 90 AWAY FROM THE COAST. COASTAL AREAS WILL BE COOLER DUE TO
A SEA BREEZE BUT STILL LOW TO MID 80S BEFORE THE BREEZE SETS UP.
THERE IS THE POTENTIAL FOR SOME FOG AGAIN LATER TONIGHT ESPECIALLY
FOR THE DOWNEAST AND COASTAL AREAS. THE LATEST NAM AND GFS
SOUNDINGS PICK THIS UP WELL W/AN INVERSION SETTING UP AND MOISTURE
TRAPPED RIGHT AT THE BLYR. TEMPERATURES OVERNIGHT WILL BE A TAD
WARMER THAN SATURDAY NIGHT W/READINGS EXPECTED TO BE IN THE LOW TO
MID 60S.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
A STRONG UPPER LEVEL RIDGE WILL BUILD WESTWARD FROM THE MID
ATLANTIC REGION AND BE CENTERED NEAR THE OH/IN BORDER BY 00Z TUE.
THIS WILL KEEP A WESTERLY FLOW OF VERY WARM AIR ACROSS THE REGION
ON MONDAY. H85 TEMPS OF +17 TO +18 C WITH H925 TEMPS +23 TO +25 C.
EXPECT HIGH TEMPERATURES ON MONDAY TO RANGE FROM THE UPPER 80S TO
LOWER 90S ACROSS MUCH OF THE REGION AWAY FROM THE COAST. A WEAK
COLD FRONT WILL CROSS THE REGION DURING MONDAY AFTERNOON BUT WITH
LITTLE IN THE WAY OF MOISTURE NOT EXPECTING ANYTHING MORE THAN
SOME INCREASING CLOUDS WITH THE PASSAGE OF THE FRONT. EXPECT
MAINLY CLEAR SKIES MONDAY NIGHT WITH LOW TEMPERATURES MAINLY IN
THE 60S. TUESDAY WILL BE ANOTHER MAINLY DRY DAY BUT IT WILL BE A
TAD COOLER THAN MONDAY WITH HIGH TEMPERATURES GENERALLY IN THE LOW
TO MID 80S NORTH AND NEAR 90 DEGREES ACROSS CENTRAL AND INTERIOR
DOWNEAST.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE STRONG UPPER RIDGE WILL CONTINUE TO BUILD WESTWARD AND BE CENTERED
NEAR IL BY 00Z THU. AS THE UPPER RIDGE BUILDS WEST THE UPPER FLOW
ACROSS OUR AREA WILL BECOME MORE ZONAL DURING WEDNESDAY ALLOWING A
COLD FRONT TO CROSS THE REGION LATER WEDNESDAY AND WEDNESDAY
EVENING. LOOKS LIKE THE STAGE COULD BE SET FOR STRONG TO POSSIBLY
SEVERE CONVECTION TO DEVELOP WEDNESDAY AFTERNOON. STILL WAY TOO EARLY
FOR ANY MENTION OF ENHANCED WORDING AT THIS TIME BUT THE THREAT WILL
NEED TO BE MONITORED.
THE FRONT WILL MOVE EAST OF THE COAST BY EARLY THURSDAY MORNING AS
COOLER AND DRIER AIR BUILD IN AS HIGH PRESSURE BUILDS EAST. A ZONAL
FLOW WILL KEEP THE CHANCE FOR SHOWERS IN THE FORECAST FOR MUCH OF
THE REMAINDER OF THE EXTENDED PERIOD WITH TEMPERATURES NEAR SEASONAL
LEVELS.
&&
.AVIATION /17Z SUNDAY THROUGH THURSDAY/...
NEAR TERM: VFR THROUGH TONIGHT W/THE EXCEPTION FOR KBGR AND KBHB
AS SOME SHALLOW FOG COULD ALLOW FOR MVFR AND POSSIBLY IFR BRIEFLY
EARLY SUNDAY MORNING.
SHORT TERM: MAINLY VFR MONDAY AND TUESDAY. A COLD FRONT WILL CROSS
THE REGION LATER WEDNESDAY AND WEDNESDAY EVENING. CONFIDENCE IS
INCREASING FOR WIDESPREAD THUNDERSTORMS TO DEVELOP IN ADVANCE OF
THE FRONT WEDNESDAY AFTERNOON RESULTING ON PERIODS OF MVFR/IFR
CONDITIONS IN AND HEAVIER SHOWERS/THUNDERSTORMS. MAINLY VFR
RETURNS FOR THURSDAY.
&&
.MARINE...
NEAR TERM: A SWELL WILL CONTINUE THROUGH TONIGHT W/WAVE HEIGHTS OF
2 FT. WINDS WILL BE LIGHT AVERAGING SPEEDS OF LESS THAN 10 KTS.
SHORT TERM: WINDS/SEAS SHOULD REMAIN BELOW SCA LEVELS THROUGH THE
PERIOD.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HASTINGS/HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HASTINGS/HEWITT/DUDA
MARINE...HASTINGS/HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS GRAY ME
1242 PM EDT SUN JUL 14 2013
.SYNOPSIS...
WARMER AND MORE HUMID HIGH PRESSURE BUILDS OVER THE REGION THROUGH
THE MIDDLE OF THE WEEK. IT SHOULD BE MAINLY RAIN FREE THROUGH
TUESDAY. BY MID-WEEK...WE WILL SEE SEVERAL ATTEMPTS BY A COLD
FRONT TO MOVE SOUTH INTO THE HIGH PRESSURE...AND EVEN THOUGH IT
WILL NOT REALLY BREAK THE WARM AND HUMID AIR...IT WILL PRODUCE THE
CHANCE FOR SHOWERS AND THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
1240 PM...ONLY MINOR ADJUSTMENT TO 1ST PERIOD GRIDS TO REFLECT THE
PRESENT MESONET VALUES FOR THIS ESTF UPDATE.
PREV DISC...
925 AM...I MADE SOME ADJUSTMENTS FOR SKY COVER AS LATEST GOES
IMAGERY INDICATING A LINGERING AREA OF MID CLOUDS ACROSS NORTHERN
NEW HAMPSHIRE INTO WESTERN MAINE. OTHERWISE...I ADJUSTED 1ST
PERIOD GRIDS BASED LARGELY TO REFLECT THE MESONET AND TO
INCORPORATE THE LATEST HRRR OUTPUT INTO SURFACE WIND GRIDS.
PREV DISC...
STRATUS OFFSHORE BEHAVING WELL...AND MAINLY STAYING THERE...BUT
OCCNLY CREEPING ONSHORE BRIEFLY. THIS FOG/CLOUD BANK WILL LKLY
REMAIN OFFSHORE THROUGH THE DAY...BUT SHOULD CREEP BACK FROM THE
COAST THIS MORNING. MEANWHILE OVER NH STRATUS THAT FORMED LAST
EVENING IS NOT HOLDING TOGETHER VERY WELL...AND LOOKS PATCHY FOR
THIS MORNING.
THE 500MB RIDGE BUILDS JUST TO OUR SW TODAY...WITH HEIGHTS
APPROACHING 6000 METERS. THE NAM/GFS CONTINUE TO WANT TO PRODUCE
SOME QPF IN SRN NH AND SW ME AROUND 18Z TODAY...BUT DO NOT SEE IT AS
ANY SORT OF WIDESPREAD EVENT. LOOKING AT THE MESOSCALE MODELS...THE
RAP/HRRR AND LOCAL WRF...IT LOOKS MORE LIKE SOME ISOLD CONVECTION
DEVELOPING. GIVEN THE SURGE OF LOW-LVL MOISTURE THIS MORNING...AND
PERHAPS SOME DIFFERENTIAL HEATING GENERATED FROM LINGERING CLUSTERS
OF STRATUS AND ALTOSTRATUS...THIS MAY BE THE CASE. HAVE CALLED IT
ISOLD SHRA/TSRA...ALTHOUGH WITH DECENT MID-LVL CAPPING IT WILL BE
HARD TO GENERATE ANY TALL CUMULUS AND STRONGER UPDRAFTS.
MAX TEMPS SHOULD CLIMB WELL INTO THE 80S INLAND...WITH A FEW 90S
IN THE HOT SPOTS. LINGERING MORNING CLOUDS COULD SHAVE A DEGREE OR
TWO OFF THE HIGHS IN SOME SPOTS IN SRN NH. AND SEA BREEZE WILL
DEVELOP ALONG THE COAST THIS AFTERNOON.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH 6 PM MONDAY/...
FOR TONIGHT...INLAND AREAS SHOULD CLEAR OF MOST CLOUDS...BUT WILL
HAVE TO WATCH FOR OFFSHORE FOG AND CLOUDS WORKING IN ALONG THE
COAST. WE SHOULD RETURN TO HUMID CONDITIONS...WITH TDS IN THE
60S...THIS WILL LIMIT LOWS TO LOW 60S IN THE N...AND MID TO UPPER
60S EVERYWHERE ELSE.
MONDAY LOOKS TO BE HOT AND HUMID ACROSS ALMOST ALL THE CWA. AS THE
500 MB RIDGE RETROGRADES WWD...WILL SEE MID-UPP LVL ANTICYCLONIC
FLOW DEVELOP...WHICH WILL PRODUCE ENOUGH SUBSIDENCE TO KEEP US HOT
AND RAIN FREE. HIGHS INLAND WILL BE IN THE UPPER 80S TO LOWER 90S
WITH TDS IN THE MID TO UPPER 60S. SHOULD SEE A LITTLE BETTER SW
FLOW AT MID-LVLS...WHICH SHOULD MIX DOWN TO THE SFC A BIT..AND
KEEP SEA BREEZE FROM MOVING AS FAR INLAND AS IT MOVES ONSHORE
LATER IN THE DAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MODELS CONTINUE TO SHOW A WEAKENING BACKDOOR FRONT PUSHING
SOUTHWARD DURING THE DAY TUESDAY AS THE RIDGE OF HIGH PRESSURE
SLIPS SOUTHWARD. THE FRONT THEN LIFTS EAST DURING THE DAY
WEDNESDAY. MODELS HAVE BEEN FAIRLY CONSISTENT WITH THIS
FEATURE...ALTHOUGH ONLY WIDELY SCATTERED SHOWERS/TSTMS POSSIBLE
WITH THIS FEATURE AS ATMOSPHERE ONLY BECOMES SLIGHTLY UNSTABLE.
OTHER WEAKENING FRONTS ARE FORECAST TO MOVE INTO THE REGION
WEDNESDAY AND THURSDAY...EACH BRINGING THE THREAT OF SHOWERS OR
THUNDERSTORMS. MODELS CONTINUE TO SHOW A WAVE MOVING ALONG THE
FRONTAL BOUNDARY LATE THURSDAY AND FRIDAY...INCREASING THE THREAT
OF SHOWER AND THUNDERSTORMS LATE IN THE WEEK.
MODELS HAVE BACKED OFF STRONG FRONTAL PASSAGE LATE IN
WEEK...INSTEAD BRINGING A SOMEWHAT WEAKER FRONT THROUGH EARLY
NEXT WEEK.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
SHORT TERM...MAINLY VFR THROUGH TODAY. FOG/STRATUS JUST NOT
GETTING ORGANIZED...ALTHOUGH IT IS OUT THERE EARLY THIS MORNING.
CANNOT RULE SOME PERIODS OF MVFR THROUGH ABOUT 13Z. FOG/CLOUD BANK
LIKELY TO LINGER OFFSHORE TODAY...AND COULD MOVE ONSHORE AROUND OR
SHORTLY AFTER SUNSET AT THE COASTAL TERMINALS THIS EVENING AND
INTO THE OVERNIGHT. VLY FOG ALSO A POSSIBILITY TONIGHT. ALL
TERMINALS SHOULD BE VFR DURING THE DAY ON MONDAY.
LONG TERM...MAINLY VFR CONDITIONS EXPECTED THROUGH THURSDAY WITH
IFR CONDITIONS POSSIBLE IN EARLY MORNING VALLEY FOG IN FAVORED
LOCATIONS. MVFR CONDITIONS ALSO POSSIBLE IN AFTERNOON SHOWERS AND
THUNDERSTORMS EACH DAY. ONLY WIDELY SCATTERED SHOWERS/TSTMS
EXPECTED TUESDAY...BECOMING MORE NUMEROUS BY THURSDAY.
&&
.MARINE...
SHORT TERM...WINDS WILL REMAIN LIGHT AND SEAS BELOW SMALL CRAFT
THRESHOLD. ONLY ISSUE WILL BE LOWERED VSBY AS FOG BANK LOOKS TO
SIT OFFSHORE TODAY...AND POSSIBLY MOVE ONSHORE THIS EVENING.
LONG TERM...WINDS AND SEAS EXPECTED TO REMAIN BELOW SCA CRITERIA.
AREAS OF FOG MAY RESTRICT VISIBILITIES...ESPECIALLY IN THE
MORNINGS.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
ES
AREA FORECAST DISCUSSION
NWS CARIBOU ME
927 AM EDT SUN JUL 14 2013
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN ACROSS THE REGION THROUGH EARLY NEXT
WEEK WHILE A WEAK COLD FRONT IS EXPECTED TO CROSS THE AREA ON
MONDAY. A STRONGER COLD FRONT WILL APPROACH FROM THE NORTHWEST
LATER WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
925 AM UPDATE...SATELLITE IMAGERY IS SHOWING MID AND HIGH CLOUDS
SPILLING INTO PORTIONS OF THE FORECAST AREA THIS MORNING. HAVE
UPDATED THE SKY COVER FORECAST ACCORDINGLY. OTHERWISE, THE
PREVIOUS FORECAST IS ON TRACK AND NO OTHER CHANGES WERE NEEDED.
PREVIOUS DISCUSSION...CONTINUED WARM AND DRY THIS TERM. A LARGE
RIDGE OF HIGH PRES WILL REMAIN IN CONTROL W/ANOTHER DAY OF VERY
WARM TEMPERATURES.
LATEST SATL IR IMAGERY SHOWED SOME MID AND HIGH CLOUDS ROLLING
OVER THE UPPER RIDGE INTO PORTIONS OF NORTHERN AND EASTERN MAINE.
THE 00Z UA SHOWED A 50KT JETLET IN THE UPPER LEVELS ACROSS QUEBEC
AIDING IN THE CLOUDS PUSHING TOWARD THE CROWN OF MAINE. SOME STRATUS
AND FOG DEVELOPING OVER SWRN MAINE NEAR THE WATERVILLE AREA AND
ANOTHER BATCH SITTING OFF THE MAINE COAST. SATL LOOP SHOWED THIS
STRATUS AND FOG SLOWLY EDGING NORTHWARD TOWARD THE THE DOWNEAST
AND COAST. DECIDED TO ADD SOME PATCHY FOR THE INTERIOR DONWEAST
AND THE COAST. STRATUS AND FOG WILL LIFT AND BURN AFTER SUNRISE
THIS MORNING. THE LATEST HRRR AND LAMP GUIDANCE DOING QUITE WELL
W/THE TEMPERATURE PROFILE ATTM PER THE 06Z OBS AND HAVE LEANED
THIS WAY FOR THE DAYTIME HIGHS TODAY WHICH SHOWS UPPER 80S TO
AROUND 90 AWAY FROM THE COAST. COASTAL AREAS WILL BE COOLER DUE TO
A SEA BREEZE BUT STILL LOW TO MID 80S BEFORE THE BREEZE SETS UP.
THERE IS THE POTENTIAL FOR SOME FOG AGAIN LATER TONIGHT ESPECIALLY
FOR THE DOWNEAST AND COASTAL AREAS. THE LATEST NAM AND GFS
SOUNDINGS PICK THIS UP WELL W/AN INVERSION SETTING UP AND MOISTURE
TRAPPED RIGHT AT THE BLYR. TEMPERATURES OVERNIGHT WILL BE A TAD
WARMER THAN SATURDAY NIGHT W/READINGS EXPECTED TO BE IN THE LOW TO
MID 60S.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
A STRONG UPPER LEVEL RIDGE WILL BUILD WESTWARD FROM THE MID
ATLANTIC REGION AND BE CENTERED NEAR THE OH/IN BORDER BY 00Z TUE.
THIS WILL KEEP A WESTERLY FLOW OF VERY WARM AIR ACROSS THE REGION
ON MONDAY. H85 TEMPS OF +17 TO +18 C WITH H925 TEMPS +23 TO +25 C.
EXPECT HIGH TEMPERATURES ON MONDAY TO RANGE FROM THE UPPER 80S TO
LOWER 90S ACROSS MUCH OF THE REGION AWAY FROM THE COAST. A WEAK
COLD FRONT WILL CROSS THE REGION DURING MONDAY AFTERNOON BUT WITH
LITTLE IN THE WAY OF MOISTURE NOT EXPECTING ANYTHING MORE THAN
SOME INCREASING CLOUDS WITH THE PASSAGE OF THE FRONT. EXPECT
MAINLY CLEAR SKIES MONDAY NIGHT WITH LOW TEMPERATURES MAINLY IN
THE 60S. TUESDAY WILL BE ANOTHER MAINLY DRY DAY BUT IT WILL BE A
TAD COOLER THAN MONDAY WITH HIGH TEMPERATURES GENERALLY IN THE LOW
TO MID 80S NORTH AND NEAR 90 DEGREES ACROSS CENTRAL AND INTERIOR
DOWNEAST.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE STRONG UPPER RIDGE WILL CONTINUE TO BUILD WESTWARD AND BE CENTERED
NEAR IL BY 00Z THU. AS THE UPPER RIDGE BUILDS WEST THE UPPER FLOW
ACROSS OUR AREA WILL BECOME MORE ZONAL DURING WEDNESDAY ALLOWING A
COLD FRONT TO CROSS THE REGION LATER WEDNESDAY AND WEDNESDAY
EVENING. LOOKS LIKE THE STAGE COULD BE SET FOR STRONG TO POSSIBLY
SEVERE CONVECTION TO DEVELOP WEDNESDAY AFTERNOON. STILL WAY TOO EARLY
FOR ANY MENTION OF ENHANCED WORDING AT THIS TIME BUT THE THREAT WILL
NEED TO BE MONITORED.
THE FRONT WILL MOVE EAST OF THE COAST BY EARLY THURSDAY MORNING AS
COOLER AND DRIER AIR BUILD IN AS HIGH PRESSURE BUILDS EAST. A ZONAL
FLOW WILL KEEP THE CHANCE FOR SHOWERS IN THE FORECAST FOR MUCH OF
THE REMAINDER OF THE EXTENDED PERIOD WITH TEMPERATURES NEAR SEASONAL
LEVELS.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
NEAR TERM: VFR THROUGH TONIGHT W/THE EXCEPTION FOR KBGR AND KBHB
AS SOME SHALLOW FOG COULD ALLOW FOR MVFR AND POSSIBLY IFR BRIEFLY
EARLY SUNDAY MORNING.
SHORT TERM: MAINLY VFR MONDAY AND TUESDAY. A COLD FRONT WILL CROSS
THE REGION LATER WEDNESDAY AND WEDNESDAY EVENING. CONFIDENCE IS
INCREASING FOR WIDESPREAD THUNDERSTORMS TO DEVELOP IN ADVANCE OF
THE FRONT WEDNESDAY AFTERNOON RESULTING ON PERIODS OF MVFR/IFR
CONDITIONS IN AND HEAVIER SHOWERS/THUNDERSTORMS. MAINLY VFR
RETURNS FOR THURSDAY.
&&
.MARINE...
NEAR TERM: A SWELL WILL CONTINUE THROUGH TONIGHT W/WAVE HEIGHTS OF
2 FT. WINDS WILL BE LIGHT AVERAGING SPEEDS OF LESS THAN 10 KTS.
SHORT TERM: WINDS/SEAS SHOULD REMAIN BELOW SCA LEVELS THROUGH THE
PERIOD.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HASTINGS/HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HASTINGS/HEWITT/DUDA
MARINE...HASTINGS/HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS GRAY ME
924 AM EDT SUN JUL 14 2013
.SYNOPSIS...
WARMER AND MORE HUMID HIGH PRESSURE BUILDS OVER THE REGION THROUGH
THE MIDDLE OF THE WEEK. IT SHOULD BE MAINLY RAIN FREE THROUGH
TUESDAY. BY MID-WEEK...WE WILL SEE SEVERAL ATTEMPTS BY A COLD
FRONT TO MOVE SOUTH INTO THE HIGH PRESSURE...AND EVEN THOUGH IT
WILL NOT REALLY BREAK THE WARM AND HUMID AIR...IT WILL PRODUCE THE
CHANCE FOR SHOWERS AND THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
925 AM...I MADE SOME ADJUSTMENTS FOR SKY COVER AS LATEST GOES
IMAGERY INDICATING A LINGERING AREA OF MID CLOUDS ACROSS NORTHERN
NEW HAMPSHIRE INTO WESTERN MAINE. OTHERWISE...I ADJUSTED 1ST
PERIOD GRIDS BASED LARGELY TO REFLECT THE MESONET AND TO
INCORPORATE THE LATEST HRRR OUTPUT INTO SURFACE WIND GRIDS.
PREV DISC...
STRATUS OFFSHORE BEHAVING WELL...AND MAINLY STAYING THERE...BUT
OCCNLY CREEPING ONSHORE BRIEFLY. THIS FOG/CLOUD BANK WILL LKLY
REMAIN OFFSHORE THROUGH THE DAY...BUT SHOULD CREEP BACK FROM THE
COAST THIS MORNING. MEANWHILE OVER NH STRATUS THAT FORMED LAST
EVENING IS NOT HOLDING TOGETHER VERY WELL...AND LOOKS PATCHY FOR
THIS MORNING.
THE 500MB RIDGE BUILDS JUST TO OUR SW TODAY...WITH HEIGHTS
APPROACHING 6000 METERS. THE NAM/GFS CONTINUE TO WANT TO PRODUCE
SOME QPF IN SRN NH AND SW ME AROUND 18Z TODAY...BUT DO NOT SEE IT AS
ANY SORT OF WIDESPREAD EVENT. LOOKING AT THE MESOSCALE MODELS...THE
RAP/HRRR AND LOCAL WRF...IT LOOKS MORE LIKE SOME ISOLD CONVECTION
DEVELOPING. GIVEN THE SURGE OF LOW-LVL MOISTURE THIS MORNING...AND
PERHAPS SOME DIFFERENTIAL HEATING GENERATED FROM LINGERING CLUSTERS
OF STRATUS AND ALTOSTRATUS...THIS MAY BE THE CASE. HAVE CALLED IT
ISOLD SHRA/TSRA...ALTHOUGH WITH DECENT MID-LVL CAPPING IT WILL BE
HARD TO GENERATE ANY TALL CUMULUS AND STRONGER UPDRAFTS.
MAX TEMPS SHOULD CLIMB WELL INTO THE 80S INLAND...WITH A FEW 90S
IN THE HOT SPOTS. LINGERING MORNING CLOUDS COULD SHAVE A DEGREE OR
TWO OFF THE HIGHS IN SOME SPOTS IN SRN NH. AND SEA BREEZE WILL
DEVELOP ALONG THE COAST THIS AFTERNOON.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH 6 PM MONDAY/...
FOR TONIGHT...INLAND AREAS SHOULD CLEAR OF MOST CLOUDS...BUT WILL
HAVE TO WATCH FOR OFFSHORE FOG AND CLOUDS WORKING IN ALONG THE
COAST. WE SHOULD RETURN TO HUMID CONDITIONS...WITH TDS IN THE
60S...THIS WILL LIMIT LOWS TO LOW 60S IN THE N...AND MID TO UPPER
60S EVERYWHERE ELSE.
MONDAY LOOKS TO BE HOT AND HUMID ACROSS ALMOST ALL THE CWA. AS THE
500 MB RIDGE RETROGRADES WWD...WILL SEE MID-UPP LVL ANTICYCLONIC
FLOW DEVELOP...WHICH WILL PRODUCE ENOUGH SUBSIDENCE TO KEEP US HOT
AND RAIN FREE. HIGHS INLAND WILL BE IN THE UPPER 80S TO LOWER 90S
WITH TDS IN THE MID TO UPPER 60S. SHOULD SEE A LITTLE BETTER SW
FLOW AT MID-LVLS...WHICH SHOULD MIX DOWN TO THE SFC A BIT..AND
KEEP SEA BREEZE FROM MOVING AS FAR INLAND AS IT MOVES ONSHORE
LATER IN THE DAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MODELS CONTINUE TO SHOW A WEAKENING BACKDOOR FRONT PUSHING
SOUTHWARD DURING THE DAY TUESDAY AS THE RIDGE OF HIGH PRESSURE
SLIPS SOUTHWARD. THE FRONT THEN LIFTS EAST DURING THE DAY
WEDNESDAY. MODELS HAVE BEEN FAIRLY CONSISTENT WITH THIS
FEATURE...ALTHOUGH ONLY WIDELY SCATTERED SHOWERS/TSTMS POSSIBLE
WITH THIS FEATURE AS ATMOSPHERE ONLY BECOMES SLIGHTLY UNSTABLE.
OTHER WEAKENING FRONTS ARE FORECAST TO MOVE INTO THE REGION
WEDNESDAY AND THURSDAY...EACH BRINGING THE THREAT OF SHOWERS OR
THUNDERSTORMS. MODELS CONTINUE TO SHOW A WAVE MOVING ALONG THE
FRONTAL BOUNDARY LATE THURSDAY AND FRIDAY...INCREASING THE THREAT
OF SHOWER AND THUNDERSTORMS LATE IN THE WEEK.
MODELS HAVE BACKED OFF STRONG FRONTAL PASSAGE LATE IN
WEEK...INSTEAD BRINGING A SOMEWHAT WEAKER FRONT THROUGH EARLY
NEXT WEEK.
&&
.AVIATION /13Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...MAINLY VFR THROUGH TODAY. FOG/STRATUS JUST NOT
GETTING ORGANIZED...ALTHOUGH IT IS OUT THERE EARLY THIS MORNING.
CANNOT RULE SOME PERIODS OF MVFR THROUGH ABOUT 13Z. FOG/CLOUD BANK
LIKELY TO LINGER OFFSHORE TODAY...AND COULD MOVE ONSHORE AROUND OR
SHORTLY AFTER SUNSET AT THE COASTAL TERMINALS THIS EVENING AND
INTO THE OVERNIGHT. VLY FOG ALSO A POSSIBILITY TONIGHT. ALL
TERMINALS SHOULD BE VFR DURING THE DAY ON MONDAY.
LONG TERM...MAINLY VFR CONDITIONS EXPECTED THROUGH THURSDAY WITH
IFR CONDITIONS POSSIBLE IN EARLY MORNING VALLEY FOG IN FAVORED
LOCATIONS. MVFR CONDITIONS ALSO POSSIBLE IN AFTERNOON SHOWERS AND
THUNDERSTORMS EACH DAY. ONLY WIDELY SCATTERED SHOWERS/TSTMS
EXPECTED TUESDAY...BECOMING MORE NUMEROUS BY THURSDAY.
&&
.MARINE...
SHORT TERM...WINDS WILL REMAIN LIGHT AND SEAS BELOW SMALL CRAFT
THRESHOLD. ONLY ISSUE WILL BE LOWERED VSBY AS FOG BANK LOOKS TO
SIT OFFSHORE TODAY...AND POSSIBLY MOVE ONSHORE THIS EVENING.
LONG TERM...WINDS AND SEAS EXPECTED TO REMAIN BELOW SCA CRITERIA.
AREAS OF FOG MAY RESTRICT VISIBILITIES...ESPECIALLY IN THE
MORNINGS.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
ES
AREA FORECAST DISCUSSION
NWS CARIBOU ME
701 AM EDT SUN JUL 14 2013
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN ACROSS THE REGION THROUGH EARLY NEXT
WEEK WHILE A WEAK COLD FRONT IS EXPECTED TO CROSS THE AREA ON
MONDAY. A STRONGER COLD FRONT WILL APPROACH FROM THE NORTHWEST
LATER WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
655 AM UPDATE: ADJUSTED THE HRLY TEMPERATURES TO ACCOUNT FOR THE
CURRENT CONDITIONS. THE FOG HAS BURNED OFF FOR THE MOST PART
W/SOME PATCHY FOG STILL LINGERING RIGHT ALONG THE IMMEDIATE
COAST AND THIS WILL BURN OFF IN AN HOUR OR SO. REST OF THE FCST
LOOKS OK ATTM.
PREVIOUS DISCUSSION...
CONTINUED WARM AND DRY THIS TERM. A LARGE RIDGE OF HIGH PRES WILL
REMAIN IN CONTROL W/ANOTHER DAY OF VERY WARM TEMPERATURES.
LATEST SATL IR IMAGERY SHOWED SOME MID AND HIGH CLOUDS ROLLING
OVER THE UPPER RIDGE INTO PORTIONS OF NORTHERN AND EASTERN MAINE.
THE 00Z UA SHOWED A 50KT JETLET IN THE UPPER LEVELS ACROSS QUEBEC
AIDING IN THE CLOUDS PUSHING TOWARD THE CROWN OF MAINE. SOME STRATUS
AND FOG DEVELOPING OVER SWRN MAINE NEAR THE WATERVILLE AREA AND
ANOTHER BATCH SITTING OFF THE MAINE. SATL LOOP SHOWED THIS STRATUS
AND FOG SLOWLY EDGING NORTHWARD TOWARD THE THE DOWNEAST AND COAST.
DECIDED TO ADD SOME PATCHY FOR THE INTERIOR DONWEAST AND THE
COAST. STRATUS AND FOG WILL LIFT AND BURN AFTER SUNRISE THIS
MORNING. THE LATEST HRRR AND LAMP GUIDANCE DOING QUITE WELL W/THE
TEMPERATURE PROFILE ATTM PER THE 06Z OBS AND HAVE LEANED THIS WAY
FOR THE DAYTIME HIGHS TODAY WHICH SHOWS UPPER 80S TO AROUND 90
AWAY FROM THE COAST. COASTAL AREAS WILL BE COOLER DUE TO A SEA
BREEZE BUT STILL LOW TO MID 80S BEFORE THE BREEZE SETS UP.
THERE IS THE POTENTIAL FOR SOME FOG AGAIN LATER TONIGHT ESPECIALLY
FOR THE DOWNEAST AND COASTAL AREAS. THE LATEST NAM AND GFS
SOUNDINGS PICK THIS UP WELL W/AN INVERSION SETTING UP AND MOISTURE
TRAPPED RIGHT AT THE BLYR. TEMPERATURES OVERNIGHT WILL BE A TAD
WARMER THAN SATURDAY NIGHT W/READINGS EXPECTED TO BE IN THE LOW TO
MID 60S.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
A STRONG UPPER LEVEL RIDGE WILL BUILD WESTWARD FROM THE MID
ATLANTIC REGION AND BE CENTERED NEAR THE OH/IN BORDER BY 00Z TUE.
THIS WILL KEEP A WESTERLY FLOW OF VERY WARM AIR ACROSS THE REGION
ON MONDAY. H85 TEMPS OF +17 TO +18 C WITH H925 TEMPS +23 TO +25 C.
EXPECT HIGH TEMPERATURES ON MONDAY TO RANGE FROM THE UPPER 80S TO
LOWER 90S ACROSS MUCH OF THE REGION AWAY FROM THE COAST. A WEAK
COLD FRONT WILL CROSS THE REGION DURING MONDAY AFTERNOON BUT WITH
LITTLE IN THE WAY OF MOISTURE NOT EXPECTING ANYTHING MORE THAN
SOME INCREASING CLOUDS WITH THE PASSAGE OF THE FRONT. EXPECT
MAINLY CLEAR SKIES MONDAY NIGHT WITH LOW TEMPERATURES MAINLY IN
THE 60S. TUESDAY WILL BE ANOTHER MAINLY DRY DAY BUT IT WILL BE A
TAD COOLER THAN MONDAY WITH HIGH TEMPERATURES GENERALLY IN THE LOW
TO MID 80S NORTH AND NEAR 90 DEGREES ACROSS CENTRAL AND INTERIOR
DOWNEAST.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE STRONG UPPER RIDGE WILL CONTINUE TO BUILD WESTWARD AND BE CENTERED
NEAR IL BY 00Z THU. AS THE UPPER RIDGE BUILDS WEST THE UPPER FLOW
ACROSS OUR AREA WILL BECOME MORE ZONAL DURING WEDNESDAY ALLOWING A
COLD FRONT TO CROSS THE REGION LATER WEDNESDAY AND WEDNESDAY
EVENING. LOOKS LIKE THE STAGE COULD BE SET FOR STRONG TO POSSIBLY
SEVERE CONVECTION TO DEVELOP WEDNESDAY AFTERNOON. STILL WAY TO EARLY
FOR ANY MENTION OF ENHANCED WORDING AT THIS TIME BUT THE THREAT WILL
NEED TO BE MONITORED.
THE FRONT WILL MOVE EAST OF THE COAST BY EARLY THURSDAY MORNING AS
COOLER AND DRIER AIR BUILD IN AS HIGH PRESSURE BUILDS EAST. A ZONAL
FLOW WILL KEEP THE CHANCE FOR SHOWERS IN THE FORECAST FOR MUCH OF
THE REMAINDER OF THE EXTENDED PERIOD WITH TEMPERATURES NEAR SEASONAL
LEVELS.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
NEAR TERM: VFR THROUGH TONIGHT W/THE EXCEPTION FOR KBGR AND KBHB
AS SOME SHALLOW FOG COULD ALLOW FOR MVFR AND POSSIBLY IFR BRIEFLY
EARLY SUNDAY MORNING.
SHORT TERM: MAINLY VFR MONDAY AND TUESDAY. A COLD FRONT WILL CROSS
THE REGION LATER WEDNESDAY AND WEDNESDAY EVENING. CONFIDENCE IS
INCREASING FOR WIDESPREAD THUNDERSTORMS TO DEVELOP IN ADVANCE OF
THE FRONT WEDNESDAY AFTERNOON RESULTING ON PERIODS OF MVFR/IFR
CONDITIONS IN AND HEAVIER SHOWERS/THUNDERSTORMS. MAINLY VFR
RETURNS FOR THURSDAY.
&&
.MARINE...
NEAR TERM: A SWELL WILL CONTINUE THROUGH TONIGHT W/WAVE HEIGHTS OF
2 FT. WINDS WILL BE LIGHT AVERAGING SPEEDS OF LESS THAN 10 KTS.
SHORT TERM: WINDS/SEAS SHOULD REMAIN BELOW SCA LEVELS THROUGH THE
PERIOD.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HEWITT/DUDA
MARINE...HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS CARIBOU ME
410 AM EDT SUN JUL 14 2013
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN ACROSS THE REGION THROUGH EARLY NEXT
WEEK WHILE A WEAK COLD FRONT IS EXPECTED TO CROSS THE AREA ON
MONDAY. A STRONGER COLD FRONT WILL APPROACH FROM THE NORTHWEST
LATER WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
CONTINUED WARM AND DRY THIS TERM. A LARGE RIDGE OF HIGH PRES
WILL REMAIN IN CONTROL W/ANOTHER DAY OF VERY WARM TEMPERATURES.
LATEST SATL IR IMAGERY SHOWED SOME MID AND HIGH CLOUDS ROLLING
OVER THE UPPER RIDGE INTO PORTIONS OF NORTHERN AND EASTERN MAINE.
THE 00Z UA SHOWED A 50KT JETLET IN THE UPPER LEVELS ACROSS QUEBEC
AIDING IN THE CLOUDS PUSHING TOWARD THE CROWN OF MAINE. SOME STRATUS
AND FOG DEVELOPING OVER SWRN MAINE NEAR THE WATERVILLE AREA AND
ANOTHER BATCH SITTING OFF THE MAINE. SATL LOOP SHOWED THIS STRATUS
AND FOG SLOWLY EDGING NORTHWARD TOWARD THE THE DOWNEAST AND COAST.
DECIDED TO ADD SOME PATCHY FOR THE INTERIOR DONWEAST AND THE
COAST. STRATUS AND FOG WILL LIFT AND BURN AFTER SUNRISE THIS
MORNING. THE LATEST HRRR AND LAMP GUIDANCE DOING QUITE WELL W/THE
TEMPERATURE PROFILE ATTM PER THE 06Z OBS AND HAVE LEANED THIS WAY
FOR THE DAYTIME HIGHS TODAY WHICH SHOWS UPPER 80S TO AROUND 90
AWAY FROM THE COAST. COASTAL AREAS WILL BE COOLER DUE TO A SEA
BREEZE BUT STILL LOW TO MID 80S BEFORE THE BREEZE SETS UP.
THERE IS THE POTENTIAL FOR SOME FOG AGAIN LATER TONIGHT ESPECIALLY
FOR THE DOWNEAST AND COASTAL AREAS. THE LATEST NAM AND GFS
SOUNDINGS PICK THIS UP WELL W/AN INVERSION SETTING UP AND MOISTURE
TRAPPED RIGHT AT THE BLYR. TEMPERATURES OVERNIGHT WILL BE A TAD
WARMER THAN SATURDAY NIGHT W/READINGS EXPECTED TO BE IN THE LOW TO
MID 60S.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
A STRONG UPPER LEVEL RIDGE WILL BUILD WESTWARD FROM THE MID
ATLANTIC REGION AND BE CENTERED NEAR THE OH/IN BORDER BY 00Z TUE.
THIS WILL KEEP A WESTERLY FLOW OF VERY WARM AIR ACROSS THE REGION
ON MONDAY. H85 TEMPS OF +17 TO +18 C WITH H925 TEMPS +23 TO +25 C.
EXPECT HIGH TEMPERATURES ON MONDAY TO RANGE FROM THE UPPER 80S TO
LOWER 90S ACROSS MUCH OF THE REGION AWAY FROM THE COAST. A WEAK
COLD FRONT WILL CROSS THE REGION DURING MONDAY AFTERNOON BUT WITH
LITTLE IN THE WAY OF MOISTURE NOT EXPECTING ANYTHING MORE THAN
SOME INCREASING CLOUDS WITH THE PASSAGE OF THE FRONT. EXPECT
MAINLY CLEAR SKIES MONDAY NIGHT WITH LOW TEMPERATURES MAINLY IN
THE 60S. TUESDAY WILL BE ANOTHER MAINLY DRY DAY BUT IT WILL BE A
TAD COOLER THAN MONDAY WITH HIGH TEMPERATURES GENERALLY IN THE LOW
TO MID 80S NORTH AND NEAR 90 DEGREES ACROSS CENTRAL AND INTERIOR
DOWNEAST.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE STRONG UPPER RIDGE WILL CONTINUE TO BUILD WESTWARD AND BE CENTERED
NEAR IL BY 00Z THU. AS THE UPPER RIDGE BUILDS WEST THE UPPER FLOW
ACROSS OUR AREA WILL BECOME MORE ZONAL DURING WEDNESDAY ALLOWING A
COLD FRONT TO CROSS THE REGION LATER WEDNESDAY AND WEDNESDAY
EVENING. LOOKS LIKE THE STAGE COULD BE SET FOR STRONG TO POSSIBLY
SEVERE CONVECTION TO DEVELOP WEDNESDAY AFTERNOON. STILL WAY TO EARLY
FOR ANY MENTION OF ENHANCED WORDING AT THIS TIME BUT THE THREAT WILL
NEED TO BE MONITORED.
THE FRONT WILL MOVE EAST OF THE COAST BY EARLY THURSDAY MORNING AS
COOLER AND DRIER AIR BUILD IN AS HIGH PRESSURE BUILDS EAST. A ZONAL
FLOW WILL KEEP THE CHANCE FOR SHOWERS IN THE FORECAST FOR MUCH OF
THE REMAINDER OF THE EXTENDED PERIOD WITH TEMPERATURES NEAR SEASONAL
LEVELS.
&&
.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
NEAR TERM: VFR THROUGH TONIGHT W/THE EXCEPTION FOR KBGR AND KBHB
AS SOME SHALLOW FOG COULD ALLOW FOR MVFR AND POSSIBLY IFR BRIEFLY
EARLY SUNDAY MORNING.
SHORT TERM: MAINLY VFR MONDAY AND TUESDAY. A COLD FRONT WILL CROSS
THE REGION LATER WEDNESDAY AND WEDNESDAY EVENING. CONFIDENCE IS
INCREASING FOR WIDESPREAD THUNDERSTORMS TO DEVELOP IN ADVANCE OF
THE FRONT WEDNESDAY AFTERNOON RESULTING ON PERIODS OF MVFR/IFR
CONDITIONS IN AND HEAVIER SHOWERS/THUNDERSTORMS. MAINLY VFR
RETURNS FOR THURSDAY.
&&
.MARINE...
NEAR TERM: A SWELL WILL CONTINUE THROUGH TONIGHT W/WAVE HEIGHTS OF
2 FT. WINDS WILL BE LIGHT AVERAGING SPEEDS OF LESS THAN 10 KTS.
SHORT TERM: WINDS/SEAS SHOULD REMAIN BELOW SCA LEVELS THROUGH THE
PERIOD.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HEWITT/DUDA
MARINE...HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
920 PM EDT MON JUL 15 2013
.SYNOPSIS...
HOT AND HUMID CONDITIONS THROUGH THE REST OF THIS WEEK AS HIGH
PRESSURE PERSISTS OVER THE MIDWEST STATES THROUGH FRIDAY. A COLD
FRONT IS EXPECTED TO APPROACH FROM THE NORTH THIS WEEKEND AND
BRING A CHANCE FOR SHOWERS AND THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
SFC HIPRES AS BECOME ELONGATED FM THE GRTLKS DOWN THE APLCNS. EVEN
THO LLVL FLOW NLY...AMS STILL PLENTY WARM AND HUMID THX TO
SPRAWLING...STRONG H5 HIGH OVER THE MIDWEST. AS ONE WUD XPCT IN A
SUCH AN AMS...00Z RAOB INDICATES A BIT OF INSTBY HAS DVLPD. HWVR...
ITS CAPPED.
SCT TSRA HV DVLPD ON SKED ACRS CENTRAL PA. THEY PRESENTLY ARE ON
APPROACH. SUBSIDENCE AND NOCTURNAL COOLING SHUD GET IN THE WAY.
EVEN STILL...18Z NAM/12Z GFS/RECENT HRRR RUNS SUGGEST A FEW TSRA
SHUD SNEAK SWD ON THE E SIDE OF THE RDG OVNGT. HV ADDED THAT POTL
/SCHC/ INTO THE DATABASE.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
HEAT ADVISORY LIMITED TO URBAN BALT-WASH WHERE THE COMBINATION OF
MOISTURE POOLING AT LOW ELEVATION /100 FT MSL SEEMS TO BE A KEY
DISCRIMINATOR DURING MARGINAL HEAT EVENTS/ AND THE URBAN HEAT
ISLAND SHOULD BRING HEAT INDICES NEAR 105F. EXPECT HEAT INDICES
AROUND 100F IN THE REST OF THE METROS AND EAST FROM THE PIEDMONT.
MAX TEMPS MID TO UPR 90S...H85 TEMPS ONLY NEAR 18 OR 19C...NOT
HIGH ENOUGH FOR 100F TEMPERATURE.
ADDED CHANCE POPS FOR TERRAIN BASED THUNDERSTORMS. COULD HAVE
REMNANT ACTIVITY IN THE AREA BY MORNING DEPENDING ON WHAT DEVELOPS
REST OF TODAY. ACTIVITY APPEARS TO BE WEST OF 1-95.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
IF "MET SUMMER" IS JUN 1-AUG 31 THEN JUL 15-16 MUST BE THE
MIDPOINT...AND IT IS AT THIS MIDPOINT THAT SUMMER HEAT/HUMIDITY
FINALLY MAKE THEIR RETURN TO THE RGN. HIGH PRES RDG OVR THE AREA
TUE-FRI W PLENTY OF SUNSHINE XPCTD. TUE-THU SHOULD BE THE HOTTEST
DAYS...W/ MID 90S FOR AFTN TEMPS OVR MUCH OF THE CWA...APRCHG 100
IN THE CITY CENTERS. PLENTY OF LO LVL MOISTURE ALREADY IN PLACE
ACROSS THE RGN...COMBINED W/ THE HIGH TEMPS THIS WL PRODUCE HEAT
INDEX VALUES APRCHG 105 IN THE AFTN IN THE DC-BALT CORRIDOR. THIS
RMNS BLO THE 110 NEEDED TO FACILITATE AN XCSV HEAT WTCH. THE
PSBLTY OF HEAT ADVISORIES ALREADY EXIST IN THE HWO.
BUT IN GOOD NEWS...AS OF NOW THIS DOES NOT APPEAR TO BE ONE OF THE
PROLONGUED 2-3 WK LENGTH HEAT WVS THAT THIS AREA SOMETIMES XPRNCS
IN JUL. MDLS HV SHOWN UPR LVL TROF MOVG OVR ERN N AMERICA FOR THE
WKND AND STILL DO. ONCE THE GRND/BLDGS HV HAD THE CHC TO ABSORB
HIGH HEAT FOR SVRL DAYS IN YRS PAST MDLS HV HAD A TENDENCY TO COOL
TEMPS TOO MUCH BEHIND A FNT. WE`LL KEEP TEMPS IN THE L90S SAT...
A90 SUN.
OF COURSE W/ A BNDRY APRCHG SAT WHEN THE RGN A) IS HUMID AND B)
HAS BEEN ABSORBING HEAT FOR MULTIPLE DAYS THIS WL LEAD TO THE PSBLTY
OF SVR CNVCTN. THIS IS ALSO OUTLOOKED IN THE HWO.
AS OF JUL 20 AREA WL HV LOST 24 MIN OF DAYLGT SINCE THE SOLSTICE.
ANOTHER HR WL BE LOST AS OF AUG 20.
&&
.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
VFR AND LIGHT/VARIABLE FLOW THROUGH TONIGHT. PATCHY MVFR FOG
AGAIN OVERNIGHT MAINLY AT CHO/MRB. CANT COMPLETELY RULE OUT A
STRAY TSRA OVNGT...SPCLY AT BWI BUT ALSO MAYBE AS FAR W AS DCA.
HWVR...THE RISK IS WAY TOO SMALL TO INFUSE INTO TAFS. DID WANT TO
MENTION IT HERE...FOR BRIEF RESTRICTIONS IF IT DOES PAN OUT.
VFR CONDS XPCTD TUE-FRI OUTSIDE OF POSSIBLE MORNING PATCHY FOG AND
LOW CHANCES FOR EVENING THUNDERSTORMS.
&&
.MARINE...
VRBL WNDS AOB 10 KT ON THE WATERS. THAT FLOW BECOMES NLY FOR
TUESDAY. WINDS XPCTD TO RMN BLO SCA VALUES DURG THE WK AHD.
THE TSRA THREAT OVERNIGHT IS NONZERO...BUT VERY LOW. SIMLR ISOLTD
CVRG PSBL TUE AFTN-EVE.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...HEAT ADVISORY FROM NOON TO 7 PM EDT TUESDAY FOR DCZ001.
MD...HEAT ADVISORY FROM NOON TO 7 PM EDT TUESDAY FOR MDZ011.
VA...HEAT ADVISORY FROM NOON TO 7 PM EDT TUESDAY FOR VAZ054.
WV...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...BAJ
NEAR TERM...HTS
SHORT TERM...BAJ
LONG TERM...ABW
AVIATION...BAJ/HTS/ABW
MARINE...BAJ/HTS/ABW
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
124 PM EDT SUN JUL 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 410 AM EDT SUN JUL 14 2013
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW AN UPR RDG
EXTENDING WWD FM THE NE CONUS THRU THE GREAT LKS ON THE SE FLANK OF
FASTER WSW FLOW ALF OVER CANADA. 00Z APX RAOB SHOWS A STABLE...BONE
DRY AIRMASS /PWAT 0.77 INCH/ CLOSER TOWARD THE CORE OF THIS UPR RDG.
SO THE SE HALF OF THE CWA IS MOCLR. FARTHER TO THE W...THERE IS A
BAND OF MAINLY MID CLDS STRETCHING FM THE NW HALF OF LK SUP SWWD
THRU MN AND INTO IOWA. IN FACT...THE 00Z MPX RAOB SHOWS A GOOD DEAL
OF MID LVL MSTR WITH PWAT 1.93 INCH...188 PCT OF NORMAL. BUT AN
ABSENCE OF ANY SGNFT DYNAMIC FORCING UNDER THE UPR RDG AXIS WITH THE
00Z GRB/MPX RAOBS INDICATING A CAPPING INVRN THAT WEAKENS A BIT
FARTHER TO THE W AWAY FM THE HIER HGTS HAS IS ALLOWING FOR ONLY SOME
ISOLD -SHRA OVER MAINLY WRN UPR MI AND NW WI WHERE THE RUC ANALYSIS
SHOWS A BIT HIER H7 DEWPTS NEAR 10C. ANOTHER FACTOR TENDING TO
RESTRICT THE SHRA COVERAGE/INTENSITY IS A FEED OF DRIER SFC-H85 AIR
FM THE S SHOWN ON THE 00Z QUAD CITIES IOWA RAOB. SPC MESOANALYSIS
INDICATES MUCAPE NOT MUCH HIER THAN 100-250 J/KG. FARTHER TO THE
NW...A FAIRLY POTENT SHRTWV JUST W OF LK WINNIPEG EMBEDDED IN THE
WSW FLOW ALF OVER CANADA IS CAUSING SOME SCT SHRA/TS UNDER AXIS OF
GREATER INSTABILITY OVER NDAKOTA/FAR NW MN. BUT VERY DRY AIRMASS
SHOWN ON THE 00Z INL RAOB IS LIMITING THE EWD PUSH OF THESE SHRA.
TODAY...AS THE UPR RDG AXIS EXPANDS TO THE W AND H7 HGTS RISE
ACCORDINGLY...MODELS IN GOOD AGREEMENT SHOWING SE EDGE OF HIER H7
DEWPTS RETREATING SLOWLY TO THE NW AS WELL. LOWER H85 DEWPTS
ARRIVING FM THE S WL ALSO TEND TO END ANY SHRA. SO WL FCST LINGERING
POPS OVER THE NW LAND CWA THIS MRNG TO PUSH OUT INTO LK SUP. WITH
ABUNDANT SUNSHINE OVER THE CENTRAL AND E ALONG WITH H85 TEMPS NEAR
17C...EXPECT HI TEMPS TO RISE WELL INTO THE 80S AGAIN AWAY FM THE
MODERATING INFLUENCE OF MAINLY LK MI IN LLVL SSW FLOW. BUT RATHER
WEAK PRES GRADIENT FCST THIS AFTN WL ALLOW FOR LK BREEZE FORMATION
OFF LK SUP AS WELL.
TONIGHT...MODELS IN GOOD AGREEMENT SHOWING AXIS OF HIER H7 MSTR
REMAINING OVER NW LK SUP OVERNGT ON THE NW FLANK OF NEARLY STNRY UPR
RDG CENTERED OVER THE LOWER GRT LKS. ANOTHER SHRTWV IS FCST TO RIDE
NEWD THRU MN LATE TNGT IN THE WSW FLOW ALF ARND THE RDG...BUT BULK
OF MODELS INDICATE ANY ASSOCIATED PCPN WL REMAIN OVER THE LK WITH
MID LVL CAPPING OVER THE LAND CWA CLOSER TO THE HIER HGTS DESPITE
ARRIVAL OF MORE HUMID LLVL AIR THAT WL ALLOW FOR SOME FOG FORMATION
AT LEAST OVER THE W HALF.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 410 AM EDT SUN JUL 14 2013
UPPER LEVEL HIGH CENTERED OVER MID ATLANTIC EXPANDS WESTWARD ACROSS
THE OHIO VALLEY AND MISSISSIPPI RIVER VALLEY INTO WEDNESDAY. LATER
WEDNESDAY THROUGH THURSDAY NORTHERN STREAM TROUGH/MID-LEVEL SPEED
MAX SMASHES THE RIDGE SOUTH OF UPPER GREAT LAKES. APPEARS THAT
NORTHERN STREAM TROUGH WILL BE STRONG ENOUGH TO PUSH SFC-H85 FRONT
ACROSS UPR MICHIGAN WED AFTN THROUGH THURSDAY. TROUBLE IS THAT FRONT
WILL NOT MOVE TOO FAR SOUTH AS IT BECOMES PARALLEL TO UPPER FLOW.
WITH FRONT CLOSE BY AND SINCE UPPER LAKES WILL BE ON NORTHERLY EDGE
OF HIGHER INSTABILITY GRADIENT AND ON SOUTHERN EDGE OF STRONGER
WINDS ALOFT...WILL HAVE CHANCE POPS WEDNESDAY THROUGH THURSDAY
NIGHT. AT THIS POINT...BEST CHANCES OF WIDESPREAD SHRA/TSRA WOULD BE
WEDNESDAY THEN AGAIN THURSDAY AFTN/EVENING. BY LATER FRIDAY AND INTO
NEXT WEEKEND...HEIGHTS FROM THE NORTH LOWER ENOUGH TO PUSH FRONT FAR
ENOUGH SOUTH TO SHOW A DRYING TREND.
HIGH PRESSURE BUILDING ALOFT ON MONDAY WHILE WEAK HIGH PRESSURE IS
OVER THE AREA AT THE SFC. COULD BE LOCALIZED LAKE BREEZES OFF LK
SUPERIOR NCNTRL AND ON KEWEENAW. PATTERN FAVORS MOST LAKE COOLING
OFF LK MICHIGAN THOUGH. WEAK CONVERGENCE ALONG LK BREEZES BUT
MLCAPES ARE MEAGER WITH SUBSIDENCE FROM BUILDING RIDGE ALOFT.
CU MAY BE ENHANCED OVR CNTRL CWA BUT WILL NOT INCLUDE ANY POPS
DUE TO MINIMAL INSTABILITY. SFC RIDGE AXIS MOVES EAST BY TUESDAY
WHILE SFC TROUGH CROSSES NORTHERN MANITOBA AND NORTHWEST ONTARIO.
GRADIENT SSW WIND SHOULD LIMIT LAKE SUPERIOR BREEZE. H85 TEMPS SURGE
TO +18C...SO EXPECT TEMPS INTO THE UPPER 80S AWAY FM LK MICHIGAN.
HIGHER DWPNT/INSTABILITY THAN MONDAY WITH MLCAPES OVER 1000
J/KG...BUT OVERALL THE LOW-LEVEL CONVERGENCE IS MINIMAL. COULD
SEE ISOLD-SCT SHRA/TSRA FORM OVER CNTRL CWA NEAREST LK MICHIGAN LAKE
BREEZE. WITH DEEP LAYER SHEAR OVER 30 KTS...CANNOT RULE OUT AN ISOLD
SVR STORM.
GENESIS REGION FOR MORE ORGANIZED SHRA/TSRA ON TUESDAY EVENING MAY
BE IN THE VCNTY OF UPPER LAKES INTO NORTHERN PLAINS CLOSER TO TAIL
END OF SFC TROUGH EXTENDING SOUTHWEST OF SFC LOW CROSSING NORTHERN
ONTARIO. MAX MOISTURE ADVECTION/LOW-LEVEL JET WOULD BE OVER NW
PORTION OF UPPER LAKES. MEAN STORM MOTION/FORWARD PROPAGATING
CORFIDI VECTORS AND 850-300MB THICKNESS SUGGEST THAT IF SHRA/TSRA
FORM IN THE EVENING THEY WOULD TRACK ACROSS UPR MICHIGAN TUE NIGHT.
WILL GO WITH LOW CHANCES ON TUESDAY NIGHT ACROSS WESTERN CWA. IDEA
MATCHES SPC SREF 3 HR PROBABILITY FOR TSRA. IF ORGANIZED CONVECTION
MATERIALIZES...WOULD AGAIN BE SOME RISK OF SVR MAINLY IN THE FORM OF
STRONG WIND GUSTS.
SFC FRONT AND DWPNTS POOLING TO NEAR 70 DEGREES IN AREA ON
WEDNESDAY. DEPENDING HOW OVERNIGHT CONVECTION GOES THERE MAY BE AN
INITIAL ROUND OF SHRA/TSRA OVER THE AREA ON WEDNESDAY MORNING WITH
ANOTHER INCREASE DURING THE AFTN. MLCAPES PUSHING 1500J/KG WITH DEEP
LAYER SHEAR 30-40 KTS INDICATES THIS COULD BE YET ANOTHER SVR
WEATHER DAY. SYNOPTIC PATTERN POINTS TO WIND/BOW ECHO TYPE OF
SITUATION. MUCH TOO EARLY TO GET CAUGHT UP IN THESE DETAILS YET
THOUGH. SOME INDICATIONS THAT FRONT MAY BE THROUGH NORTHERN TIER OF
CWA WITH MAIN FOCUS FOR AFTN CONVECTION OVER THE SCNTRL IN AREA OF
STRONGER SFC-H85 CONVERGENCE. CONSENSUS POPS HAVE THE HIGHER POPS
SCNTRL WITH LESSER POPS NEAR LK SUPERIOR. TEMPS COULD SHOW A PRETTY
SHARP RANGE ON WEDNESDAY...ESPECIALLY IF ONSHORE NORTH WINDS DEVELOP
IN THE NORTH CWA EARLIER IN THE DAY. MIXING TO H85 TEMPS STILL NEAR
+17C YIELDS HIGHS INTO THE UPPER 80S SCNTRL. 70S TO NEAR 80 DEGREES
WILL BE THE CASE NEAR LK SUPERIOR. OVERALL A LULL EXPECTED LATER
WEDNESDAY NIGHT THROUGH THURSDAY MORNING. BY THURSDAY AFTN...SFC-H85
WINDS BACKING MORE SW AHEAD OF ANOTHER SHORTWAVE/H5 SPEED MAX
DIGGING INTO NORTHERN PLAINS. H85 WARM AIR ADVECTION ALONG WITH
MOISTURE TRANSPORT AND FACT THAT UPR MICHIGAN IS FCST TO BE ALONG
NORTH EDGE OF MUCAPE GRADIENT SUGGESTS ANOTHER ROUND OF SHRA/TSRA
OVER PARTS OF THE AREA THURSDAY AFTN/THURSDAY NIGHT. MAY EVEN SEE
ANOTHER CONVECTIVE WIND TYPE OF SITUATION.
CONSENSUS POPS SHOW THE DRYING TREND KICKING IN ON FRIDAY FM NORTH
TO SOUTH AS MAIN SFC COLD FRONT PLOWS INTO THE REGION. EXPECT DRY
WEATHER AND COOLER TEMPERATURES TO BE MAIN WEATHER STORY BY TIME
NEXT WEEKEND ARRIVES. ONSHORE GRADIENT NORTH WINDS LIKELY WILL KEEP
TEMPS IN THE 60S ALONG LK SUPERIOR FRIDAY AND SATURDAY. MAY ALSO SEE
INCREASED SWIM RISK AT THAT TIME AS WELL. IN THE MEANTIME...A WARM
AND HUMID SUMMERTIME REGIME WILL BE IN PLACE THROUGH MUCH OF THE
UPCOMING WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 123 PM EDT SUN JUL 14 2013
DRIER AIR HAS OVERCOME KSAW THIS AFTERNOON...WHICH HAS KEPT SKIES
MOSTLY SUNNY THROUGH THE DAY. AS OF 17Z THIS AIR WAS SLOWLY CREEPING
NORTHWESTWARD TOWARDS KIWD/KCMX. CLOUDS AT KIWD ARE ALREADY BREAKING
UP...AND WILL CONTINUE TO DO SO THROUGH THE AFTERNOON. KCMX MAY BE A
LITTLE BIT SLOWER...AND MAY EVEN SEE A STRAY SHOWER OR TWO...BUT
CONDITIONS WILL NOT DROP BELOW VFR.
OTHERWISE...HIGH PRESSURE WILL KEEP CONDITIONS MOSTLY QUIET. WITH
VERY LIGHT WINDS...MOSTLY CLEAR SKIES...AND ANOTHER BATCH OF
MOISTURE SNEAKING IN FROM THE SOUTH OVERNIGHT...CANNOT RULE OUT SOME
PATCHY FOG DEVELOPING TONIGHT AT ALL THREE TAF SITES. FOR NOW HAVE
KEPT VISIBILITIES MVFR FOR A FIRST GUESS...AS FOG IS NOT EXPECTED TO
BE PROBLEMATIC.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 410 AM EDT SUN JUL 14 2013
WITH HIGH PRESSURE NUDGING INTO THE UPPER GREAT LAKES AND A WEAK LOW
PRESSURE TROUGH TO THE WEST...WINDS WILL GENERALLY REMAIN LESS THAN
15-20 KNOTS THROUGH THE FORECAST PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...MCD
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
741 AM EDT SUN JUL 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 410 AM EDT SUN JUL 14 2013
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW AN UPR RDG
EXTENDING WWD FM THE NE CONUS THRU THE GREAT LKS ON THE SE FLANK OF
FASTER WSW FLOW ALF OVER CANADA. 00Z APX RAOB SHOWS A STABLE...BONE
DRY AIRMASS /PWAT 0.77 INCH/ CLOSER TOWARD THE CORE OF THIS UPR RDG.
SO THE SE HALF OF THE CWA IS MOCLR. FARTHER TO THE W...THERE IS A
BAND OF MAINLY MID CLDS STRETCHING FM THE NW HALF OF LK SUP SWWD
THRU MN AND INTO IOWA. IN FACT...THE 00Z MPX RAOB SHOWS A GOOD DEAL
OF MID LVL MSTR WITH PWAT 1.93 INCH...188 PCT OF NORMAL. BUT AN
ABSENCE OF ANY SGNFT DYNAMIC FORCING UNDER THE UPR RDG AXIS WITH THE
00Z GRB/MPX RAOBS INDICATING A CAPPING INVRN THAT WEAKENS A BIT
FARTHER TO THE W AWAY FM THE HIER HGTS HAS IS ALLOWING FOR ONLY SOME
ISOLD -SHRA OVER MAINLY WRN UPR MI AND NW WI WHERE THE RUC ANALYSIS
SHOWS A BIT HIER H7 DEWPTS NEAR 10C. ANOTHER FACTOR TENDING TO
RESTRICT THE SHRA COVERAGE/INTENSITY IS A FEED OF DRIER SFC-H85 AIR
FM THE S SHOWN ON THE 00Z QUAD CITIES IOWA RAOB. SPC MESOANALYSIS
INDICATES MUCAPE NOT MUCH HIER THAN 100-250 J/KG. FARTHER TO THE
NW...A FAIRLY POTENT SHRTWV JUST W OF LK WINNIPEG EMBEDDED IN THE
WSW FLOW ALF OVER CANADA IS CAUSING SOME SCT SHRA/TS UNDER AXIS OF
GREATER INSTABILITY OVER NDAKOTA/FAR NW MN. BUT VERY DRY AIRMASS
SHOWN ON THE 00Z INL RAOB IS LIMITING THE EWD PUSH OF THESE SHRA.
TODAY...AS THE UPR RDG AXIS EXPANDS TO THE W AND H7 HGTS RISE
ACCORDINGLY...MODELS IN GOOD AGREEMENT SHOWING SE EDGE OF HIER H7
DEWPTS RETREATING SLOWLY TO THE NW AS WELL. LOWER H85 DEWPTS
ARRIVING FM THE S WL ALSO TEND TO END ANY SHRA. SO WL FCST LINGERING
POPS OVER THE NW LAND CWA THIS MRNG TO PUSH OUT INTO LK SUP. WITH
ABUNDANT SUNSHINE OVER THE CENTRAL AND E ALONG WITH H85 TEMPS NEAR
17C...EXPECT HI TEMPS TO RISE WELL INTO THE 80S AGAIN AWAY FM THE
MODERATING INFLUENCE OF MAINLY LK MI IN LLVL SSW FLOW. BUT RATHER
WEAK PRES GRADIENT FCST THIS AFTN WL ALLOW FOR LK BREEZE FORMATION
OFF LK SUP AS WELL.
TONIGHT...MODELS IN GOOD AGREEMENT SHOWING AXIS OF HIER H7 MSTR
REMAINING OVER NW LK SUP OVERNGT ON THE NW FLANK OF NEARLY STNRY UPR
RDG CENTERED OVER THE LOWER GRT LKS. ANOTHER SHRTWV IS FCST TO RIDE
NEWD THRU MN LATE TNGT IN THE WSW FLOW ALF ARND THE RDG...BUT BULK
OF MODELS INDICATE ANY ASSOCIATED PCPN WL REMAIN OVER THE LK WITH
MID LVL CAPPING OVER THE LAND CWA CLOSER TO THE HIER HGTS DESPITE
ARRIVAL OF MORE HUMID LLVL AIR THAT WL ALLOW FOR SOME FOG FORMATION
AT LEAST OVER THE W HALF.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 410 AM EDT SUN JUL 14 2013
UPPER LEVEL HIGH CENTERED OVER MID ATLANTIC EXPANDS WESTWARD ACROSS
THE OHIO VALLEY AND MISSISSIPPI RIVER VALLEY INTO WEDNESDAY. LATER
WEDNESDAY THROUGH THURSDAY NORTHERN STREAM TROUGH/MID-LEVEL SPEED
MAX SMASHES THE RIDGE SOUTH OF UPPER GREAT LAKES. APPEARS THAT
NORTHERN STREAM TROUGH WILL BE STRONG ENOUGH TO PUSH SFC-H85 FRONT
ACROSS UPR MICHIGAN WED AFTN THROUGH THURSDAY. TROUBLE IS THAT FRONT
WILL NOT MOVE TOO FAR SOUTH AS IT BECOMES PARALLEL TO UPPER FLOW.
WITH FRONT CLOSE BY AND SINCE UPPER LAKES WILL BE ON NORTHERLY EDGE
OF HIGHER INSTABILITY GRADIENT AND ON SOUTHERN EDGE OF STRONGER
WINDS ALOFT...WILL HAVE CHANCE POPS WEDNESDAY THROUGH THURSDAY
NIGHT. AT THIS POINT...BEST CHANCES OF WIDESPREAD SHRA/TSRA WOULD BE
WEDNESDAY THEN AGAIN THURSDAY AFTN/EVENING. BY LATER FRIDAY AND INTO
NEXT WEEKEND...HEIGHTS FROM THE NORTH LOWER ENOUGH TO PUSH FRONT FAR
ENOUGH SOUTH TO SHOW A DRYING TREND.
HIGH PRESSURE BUILDING ALOFT ON MONDAY WHILE WEAK HIGH PRESSURE IS
OVER THE AREA AT THE SFC. COULD BE LOCALIZED LAKE BREEZES OFF LK
SUPERIOR NCNTRL AND ON KEWEENAW. PATTERN FAVORS MOST LAKE COOLING
OFF LK MICHIGAN THOUGH. WEAK CONVERGENCE ALONG LK BREEZES BUT
MLCAPES ARE MEAGER WITH SUBSIDENCE FROM BUILDING RIDGE ALOFT.
CU MAY BE ENHANCED OVR CNTRL CWA BUT WILL NOT INCLUDE ANY POPS
DUE TO MINIMAL INSTABILITY. SFC RIDGE AXIS MOVES EAST BY TUESDAY
WHILE SFC TROUGH CROSSES NORTHERN MANITOBA AND NORTHWEST ONTARIO.
GRADIENT SSW WIND SHOULD LIMIT LAKE SUPERIOR BREEZE. H85 TEMPS SURGE
TO +18C...SO EXPECT TEMPS INTO THE UPPER 80S AWAY FM LK MICHIGAN.
HIGHER DWPNT/INSTABILITY THAN MONDAY WITH MLCAPES OVER 1000
J/KG...BUT OVERALL THE LOW-LEVEL CONVERGENCE IS MINIMAL. COULD
SEE ISOLD-SCT SHRA/TSRA FORM OVER CNTRL CWA NEAREST LK MICHIGAN LAKE
BREEZE. WITH DEEP LAYER SHEAR OVER 30 KTS...CANNOT RULE OUT AN ISOLD
SVR STORM.
GENESIS REGION FOR MORE ORGANIZED SHRA/TSRA ON TUESDAY EVENING MAY
BE IN THE VCNTY OF UPPER LAKES INTO NORTHERN PLAINS CLOSER TO TAIL
END OF SFC TROUGH EXTENDING SOUTHWEST OF SFC LOW CROSSING NORTHERN
ONTARIO. MAX MOISTURE ADVECTION/LOW-LEVEL JET WOULD BE OVER NW
PORTION OF UPPER LAKES. MEAN STORM MOTION/FORWARD PROPAGATING
CORFIDI VECTORS AND 850-300MB THICKNESS SUGGEST THAT IF SHRA/TSRA
FORM IN THE EVENING THEY WOULD TRACK ACROSS UPR MICHIGAN TUE NIGHT.
WILL GO WITH LOW CHANCES ON TUESDAY NIGHT ACROSS WESTERN CWA. IDEA
MATCHES SPC SREF 3 HR PROBABILITY FOR TSRA. IF ORGANIZED CONVECTION
MATERIALIZES...WOULD AGAIN BE SOME RISK OF SVR MAINLY IN THE FORM OF
STRONG WIND GUSTS.
SFC FRONT AND DWPNTS POOLING TO NEAR 70 DEGREES IN AREA ON
WEDNESDAY. DEPENDING HOW OVERNIGHT CONVECTION GOES THERE MAY BE AN
INITIAL ROUND OF SHRA/TSRA OVER THE AREA ON WEDNESDAY MORNING WITH
ANOTHER INCREASE DURING THE AFTN. MLCAPES PUSHING 1500J/KG WITH DEEP
LAYER SHEAR 30-40 KTS INDICATES THIS COULD BE YET ANOTHER SVR
WEATHER DAY. SYNOPTIC PATTERN POINTS TO WIND/BOW ECHO TYPE OF
SITUATION. MUCH TOO EARLY TO GET CAUGHT UP IN THESE DETAILS YET
THOUGH. SOME INDICATIONS THAT FRONT MAY BE THROUGH NORTHERN TIER OF
CWA WITH MAIN FOCUS FOR AFTN CONVECTION OVER THE SCNTRL IN AREA OF
STRONGER SFC-H85 CONVERGENCE. CONSENSUS POPS HAVE THE HIGHER POPS
SCNTRL WITH LESSER POPS NEAR LK SUPERIOR. TEMPS COULD SHOW A PRETTY
SHARP RANGE ON WEDNESDAY...ESPECIALLY IF ONSHORE NORTH WINDS DEVELOP
IN THE NORTH CWA EARLIER IN THE DAY. MIXING TO H85 TEMPS STILL NEAR
+17C YIELDS HIGHS INTO THE UPPER 80S SCNTRL. 70S TO NEAR 80 DEGREES
WILL BE THE CASE NEAR LK SUPERIOR. OVERALL A LULL EXPECTED LATER
WEDNESDAY NIGHT THROUGH THURSDAY MORNING. BY THURSDAY AFTN...SFC-H85
WINDS BACKING MORE SW AHEAD OF ANOTHER SHORTWAVE/H5 SPEED MAX
DIGGING INTO NORTHERN PLAINS. H85 WARM AIR ADVECTION ALONG WITH
MOISTURE TRANSPORT AND FACT THAT UPR MICHIGAN IS FCST TO BE ALONG
NORTH EDGE OF MUCAPE GRADIENT SUGGESTS ANOTHER ROUND OF SHRA/TSRA
OVER PARTS OF THE AREA THURSDAY AFTN/THURSDAY NIGHT. MAY EVEN SEE
ANOTHER CONVECTIVE WIND TYPE OF SITUATION.
CONSENSUS POPS SHOW THE DRYING TREND KICKING IN ON FRIDAY FM NORTH
TO SOUTH AS MAIN SFC COLD FRONT PLOWS INTO THE REGION. EXPECT DRY
WEATHER AND COOLER TEMPERATURES TO BE MAIN WEATHER STORY BY TIME
NEXT WEEKEND ARRIVES. ONSHORE GRADIENT NORTH WINDS LIKELY WILL KEEP
TEMPS IN THE 60S ALONG LK SUPERIOR FRIDAY AND SATURDAY. MAY ALSO SEE
INCREASED SWIM RISK AT THAT TIME AS WELL. IN THE MEANTIME...A WARM
AND HUMID SUMMERTIME REGIME WILL BE IN PLACE THROUGH MUCH OF THE
UPCOMING WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 741 AM EDT SUN JUL 14 2013
SOME LINGERING SCT -SHRS NEAR CMX/IWD THIS MRNG WL TEND TO DIMINISH
THIS MRNG UNDER RISING HGTS ASSOCIATED WITH BLDG RDG IN THE GREAT
LKS AND ARRIVAL OF DRIER AIR. EVEN IF ANY -SHRA IMPACT THESE
SITES...DRY LLVLS WL ENSURE VFR CONDITIONS. THEN VFR WX WL PREVAIL
THRU TNGT AT CMX/IWD AS THE RDG EXPANDS SLOWLY TO THE NW AND
DEFLECTS ANY ADDITIONAL SHRA/TS TO THE NW. SAW WL BE CLOSER THE RDG
AND DRIER AIR...SO EXPECT VFR CONDITIONS TO PREVAIL THERE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 410 AM EDT SUN JUL 14 2013
WITH HIGH PRESSURE NUDGING INTO THE UPPER GREAT LAKES AND A WEAK LOW
PRESSURE TROUGH TO THE WEST...WINDS WILL GENERALLY REMAIN LESS THAN
15-20 KNOTS THROUGH THE FORECAST PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
413 AM EDT SUN JUL 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 410 AM EDT SUN JUL 14 2013
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW AN UPR RDG
EXTENDING WWD FM THE NE CONUS THRU THE GREAT LKS ON THE SE FLANK OF
FASTER WSW FLOW ALF OVER CANADA. 00Z APX RAOB SHOWS A STABLE...BONE
DRY AIRMASS /PWAT 0.77 INCH/ CLOSER TOWARD THE CORE OF THIS UPR RDG.
SO THE SE HALF OF THE CWA IS MOCLR. FARTHER TO THE W...THERE IS A
BAND OF MAINLY MID CLDS STRETCHING FM THE NW HALF OF LK SUP SWWD
THRU MN AND INTO IOWA. IN FACT...THE 00Z MPX RAOB SHOWS A GOOD DEAL
OF MID LVL MSTR WITH PWAT 1.93 INCH...188 PCT OF NORMAL. BUT AN
ABSENCE OF ANY SGNFT DYNAMIC FORCING UNDER THE UPR RDG AXIS WITH THE
00Z GRB/MPX RAOBS INDICATING A CAPPING INVRN THAT WEAKENS A BIT
FARTHER TO THE W AWAY FM THE HIER HGTS HAS IS ALLOWING FOR ONLY SOME
ISOLD -SHRA OVER MAINLY WRN UPR MI AND NW WI WHERE THE RUC ANALYSIS
SHOWS A BIT HIER H7 DEWPTS NEAR 10C. ANOTHER FACTOR TENDING TO
RESTRICT THE SHRA COVERAGE/INTENSITY IS A FEED OF DRIER SFC-H85 AIR
FM THE S SHOWN ON THE 00Z QUAD CITIES IOWA RAOB. SPC MESOANALYSIS
INDICATES MUCAPE NOT MUCH HIER THAN 100-250 J/KG. FARTHER TO THE
NW...A FAIRLY POTENT SHRTWV JUST W OF LK WINNIPEG EMBEDDED IN THE
WSW FLOW ALF OVER CANADA IS CAUSING SOME SCT SHRA/TS UNDER AXIS OF
GREATER INSTABILITY OVER NDAKOTA/FAR NW MN. BUT VERY DRY AIRMASS
SHOWN ON THE 00Z INL RAOB IS LIMITING THE EWD PUSH OF THESE SHRA.
TODAY...AS THE UPR RDG AXIS EXPANDS TO THE W AND H7 HGTS RISE
ACCORDINGLY...MODELS IN GOOD AGREEMENT SHOWING SE EDGE OF HIER H7
DEWPTS RETREATING SLOWLY TO THE NW AS WELL. LOWER H85 DEWPTS
ARRIVING FM THE S WL ALSO TEND TO END ANY SHRA. SO WL FCST LINGERING
POPS OVER THE NW LAND CWA THIS MRNG TO PUSH OUT INTO LK SUP. WITH
ABUNDANT SUNSHINE OVER THE CENTRAL AND E ALONG WITH H85 TEMPS NEAR
17C...EXPECT HI TEMPS TO RISE WELL INTO THE 80S AGAIN AWAY FM THE
MODERATING INFLUENCE OF MAINLY LK MI IN LLVL SSW FLOW. BUT RATHER
WEAK PRES GRADIENT FCST THIS AFTN WL ALLOW FOR LK BREEZE FORMATION
OFF LK SUP AS WELL.
TONIGHT...MODELS IN GOOD AGREEMENT SHOWING AXIS OF HIER H7 MSTR
REMAINING OVER NW LK SUP OVERNGT ON THE NW FLANK OF NEARLY STNRY UPR
RDG CENTERED OVER THE LOWER GRT LKS. ANOTHER SHRTWV IS FCST TO RIDE
NEWD THRU MN LATE TNGT IN THE WSW FLOW ALF ARND THE RDG...BUT BULK
OF MODELS INDICATE ANY ASSOCIATED PCPN WL REMAIN OVER THE LK WITH
MID LVL CAPPING OVER THE LAND CWA CLOSER TO THE HIER HGTS DESPITE
ARRIVAL OF MORE HUMID LLVL AIR THAT WL ALLOW FOR SOME FOG FORMATION
AT LEAST OVER THE W HALF.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 410 AM EDT SUN JUL 14 2013
UPPER LEVEL HIGH CENTERED OVER MID ATLANTIC EXPANDS WESTWARD ACROSS
THE OHIO VALLEY AND MISSISSIPPI RIVER VALLEY INTO WEDNESDAY. LATER
WEDNESDAY THROUGH THURSDAY NORTHERN STREAM TROUGH/MID-LEVEL SPEED
MAX SMASHES THE RIDGE SOUTH OF UPPER GREAT LAKES. APPEARS THAT
NORTHERN STREAM TROUGH WILL BE STRONG ENOUGH TO PUSH SFC-H85 FRONT
ACROSS UPR MICHIGAN WED AFTN THROUGH THURSDAY. TROUBLE IS THAT FRONT
WILL NOT MOVE TOO FAR SOUTH AS IT BECOMES PARALLEL TO UPPER FLOW.
WITH FRONT CLOSE BY AND SINCE UPPER LAKES WILL BE ON NORTHERLY EDGE
OF HIGHER INSTABILITY GRADIENT AND ON SOUTHERN EDGE OF STRONGER
WINDS ALOFT...WILL HAVE CHANCE POPS WEDNESDAY THROUGH THURSDAY
NIGHT. AT THIS POINT...BEST CHANCES OF WIDESPREAD SHRA/TSRA WOULD BE
WEDNESDAY THEN AGAIN THURSDAY AFTN/EVENING. BY LATER FRIDAY AND INTO
NEXT WEEKEND...HEIGHTS FROM THE NORTH LOWER ENOUGH TO PUSH FRONT FAR
ENOUGH SOUTH TO SHOW A DRYING TREND.
HIGH PRESSURE BUILDING ALOFT ON MONDAY WHILE WEAK HIGH PRESSURE IS
OVER THE AREA AT THE SFC. COULD BE LOCALIZED LAKE BREEZES OFF LK
SUPERIOR NCNTRL AND ON KEWEENAW. PATTERN FAVORS MOST LAKE COOLING
OFF LK MICHIGAN THOUGH. WEAK CONVERGENCE ALONG LK BREEZES BUT
MLCAPES ARE MEAGER WITH SUBSIDENCE FROM BUILDING RIDGE ALOFT.
CU MAY BE ENHANCED OVR CNTRL CWA BUT WILL NOT INCLUDE ANY POPS
DUE TO MINIMAL INSTABILITY. SFC RIDGE AXIS MOVES EAST BY TUESDAY
WHILE SFC TROUGH CROSSES NORTHERN MANITOBA AND NORTHWEST ONTARIO.
GRADIENT SSW WIND SHOULD LIMIT LAKE SUPERIOR BREEZE. H85 TEMPS SURGE
TO +18C...SO EXPECT TEMPS INTO THE UPPER 80S AWAY FM LK MICHIGAN.
HIGHER DWPNT/INSTABILITY THAN MONDAY WITH MLCAPES OVER 1000
J/KG...BUT OVERALL THE LOW-LEVEL CONVERGENCE IS MINIMAL. COULD
SEE ISOLD-SCT SHRA/TSRA FORM OVER CNTRL CWA NEAREST LK MICHIGAN LAKE
BREEZE. WITH DEEP LAYER SHEAR OVER 30 KTS...CANNOT RULE OUT AN ISOLD
SVR STORM.
GENESIS REGION FOR MORE ORGANIZED SHRA/TSRA ON TUESDAY EVENING MAY
BE IN THE VCNTY OF UPPER LAKES INTO NORTHERN PLAINS CLOSER TO TAIL
END OF SFC TROUGH EXTENDING SOUTHWEST OF SFC LOW CROSSING NORTHERN
ONTARIO. MAX MOISTURE ADVECTION/LOW-LEVEL JET WOULD BE OVER NW
PORTION OF UPPER LAKES. MEAN STORM MOTION/FORWARD PROPAGATING
CORFIDI VECTORS AND 850-300MB THICKNESS SUGGEST THAT IF SHRA/TSRA
FORM IN THE EVENING THEY WOULD TRACK ACROSS UPR MICHIGAN TUE NIGHT.
WILL GO WITH LOW CHANCES ON TUESDAY NIGHT ACROSS WESTERN CWA. IDEA
MATCHES SPC SREF 3 HR PROBABILITY FOR TSRA. IF ORGANIZED CONVECTION
MATERIALIZES...WOULD AGAIN BE SOME RISK OF SVR MAINLY IN THE FORM OF
STRONG WIND GUSTS.
SFC FRONT AND DWPNTS POOLING TO NEAR 70 DEGREES IN AREA ON
WEDNESDAY. DEPENDING HOW OVERNIGHT CONVECTION GOES THERE MAY BE AN
INITIAL ROUND OF SHRA/TSRA OVER THE AREA ON WEDNESDAY MORNING WITH
ANOTHER INCREASE DURING THE AFTN. MLCAPES PUSHING 1500J/KG WITH DEEP
LAYER SHEAR 30-40 KTS INDICATES THIS COULD BE YET ANOTHER SVR
WEATHER DAY. SYNOPTIC PATTERN POINTS TO WIND/BOW ECHO TYPE OF
SITUATION. MUCH TOO EARLY TO GET CAUGHT UP IN THESE DETAILS YET
THOUGH. SOME INDICATIONS THAT FRONT MAY BE THROUGH NORTHERN TIER OF
CWA WITH MAIN FOCUS FOR AFTN CONVECTION OVER THE SCNTRL IN AREA OF
STRONGER SFC-H85 CONVERGENCE. CONSENSUS POPS HAVE THE HIGHER POPS
SCNTRL WITH LESSER POPS NEAR LK SUPERIOR. TEMPS COULD SHOW A PRETTY
SHARP RANGE ON WEDNESDAY...ESPECIALLY IF ONSHORE NORTH WINDS DEVELOP
IN THE NORTH CWA EARLIER IN THE DAY. MIXING TO H85 TEMPS STILL NEAR
+17C YIELDS HIGHS INTO THE UPPER 80S SCNTRL. 70S TO NEAR 80 DEGREES
WILL BE THE CASE NEAR LK SUPERIOR. OVERALL A LULL EXPECTED LATER
WEDNESDAY NIGHT THROUGH THURSDAY MORNING. BY THURSDAY AFTN...SFC-H85
WINDS BACKING MORE SW AHEAD OF ANOTHER SHORTWAVE/H5 SPEED MAX
DIGGING INTO NORTHERN PLAINS. H85 WARM AIR ADVECTION ALONG WITH
MOISTURE TRANSPORT AND FACT THAT UPR MICHIGAN IS FCST TO BE ALONG
NORTH EDGE OF MUCAPE GRADIENT SUGGESTS ANOTHER ROUND OF SHRA/TSRA
OVER PARTS OF THE AREA THURSDAY AFTN/THURSDAY NIGHT. MAY EVEN SEE
ANOTHER CONVECTIVE WIND TYPE OF SITUATION.
CONSENSUS POPS SHOW THE DRYING TREND KICKING IN ON FRIDAY FM NORTH
TO SOUTH AS MAIN SFC COLD FRONT PLOWS INTO THE REGION. EXPECT DRY
WEATHER AND COOLER TEMPERATURES TO BE MAIN WEATHER STORY BY TIME
NEXT WEEKEND ARRIVES. ONSHORE GRADIENT NORTH WINDS LIKELY WILL KEEP
TEMPS IN THE 60S ALONG LK SUPERIOR FRIDAY AND SATURDAY. MAY ALSO SEE
INCREASED SWIM RISK AT THAT TIME AS WELL. IN THE MEANTIME...A WARM
AND HUMID SUMMERTIME REGIME WILL BE IN PLACE THROUGH MUCH OF THE
UPCOMING WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 124 AM EDT SUN JUL 14 2013
VFR CONDITIONS WILL CONTINUE THROUGH THE FORECAST. ONLY CONCERN IS
THE SLIGHT POSSIBILITY OF CONVECTION IMPACTING FORECAST SITES OF
KCMX AND KIWD. THUNDERSTORMS OVER THE NORTHERN PLAINS ASSOCIATED
WITH A SHORT WAVE CONTINUE TO WORK EAST OVERNIGHT WHILE HIGH
PRESSURE BUILDS IN FROM THE EAST. THERE IS A CONCERN THAT THE
APPROACHING SHORT WAVE MAY INITIATE CONVECTION ALONG A TROUGH
EXTENDING ACROSS MN...FROM SW TO NE. BEST CONVERGENCE TO REMAIN
ALONG THIS BOUNDARY...AS LONG AS THE TROUGH DOES NOT PUSH TOO FAR
EAST BOTH THE WESTERN TAF SITES WILL STAY DRY OVERNIGHT AND INTO THE
EARLY DAYLIGHT HOURS EXCEPT FOR A FEW SPRINKLES UNDER AN AXIS OF
HIER MOISTURE CURRENTLY OVER WESTERN UPPER MI. BY LATE
MORNING...HIGH PRESSURE BECOMES DOMINANT WITH DRY AND STABLE
CONDITIONS PREVAILING THROUGH THE REMAINDER OF THE FORECAST.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 410 AM EDT SUN JUL 14 2013
WITH HIGH PRESSURE NUDGING INTO THE UPPER GREAT LAKES AND A WEAK LOW
PRESSURE TROUGH TO THE WEST...WINDS WILL GENERALLY REMAIN LESS THAN
15-20 KNOTS THROUGH THE FORECAST PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...RJT/KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS BILLINGS MT
305 PM MDT SUN JUL 14 2013
.SHORT TERM...VALID FOR MON AND TUE...
ACTIVE WEATHER WILL CONTINUE TONIGHT THROUGH TUE NIGHT. A BAND OF
CONVECTION CONTINUED MOVING THROUGH SE MT THIS AFTERNOON PER RADAR
IMAGERY. THE BAND WAS BEING FUELED BY JET DIVERGENCE. OTHER
CONVECTION WAS MOVING INTO THE SW PART OF THE AREA AHEAD OF A
SHORTWAVE MOVING INTO W MT AND WEAK WAVES SW OF THE AREA. A WARM
FRONT WILL MOVE N THROUGH THE REGION TONIGHT ACCOMPANIED BY
ISENTROPIC LIFT. THE HRRR HAS BEEN GENERATING CONVECTION OVER THE
S CENTRAL PART OF THE AREA FOR THE LAST FEW RUNS DURING THE
EVENING. THE RAP SHOWED 1000 J/KG OF SURFACE CAPE IN THIS AREA AND
THE WRF HAD DECENT BULK SHEAR...SO STORMS IN THIS AREA COULD BE
STRONG. A LOW-LEVEL JET WILL HELP SUSTAIN CONVECTION IN THE E
THROUGH THE NIGHT. THUS WENT WITH CHANCE POPS S TAPERING TO SLIGHT
CHANCE N DURING THE EVENING...AND SLIGHT CHANCE E OVERNIGHT.
PRECIPITABLE WATERS AROUND AN INCH WILL SUPPORT HEAVY RAIN WITH
THE THUNDERSTORMS.
MON WILL BE A PREFRONTAL DAY. SHORTWAVES WILL CONTINUE MOVING
THROUGH THE SW FLOW ALOFT. INVERTED-V SOUNDINGS WERE FORECAST FOR
THE CENTRAL AND W ZONES. KMLS WAS CAPPED ON BUFKIT. CAPES AT KBHK
WERE 1000-1500 J/KG...BUT SOUNDINGS DID NOT SHOW MUCH IN THE WAY
OF LIFT. HAD CHANCE POPS SE IN THE MORNING NEAR SHORTWAVE ENERGY
THEN ISOLATED TO SCATTERED POPS IN THE AFTERNOON AND EVENING DUE
TO ADDITIONAL SHORTWAVES AND THE APPROACH OF THE FRONT. GOOD
MIXING WILL PROMOTE HIGH TEMPERATURES IN THE 90S IN MANY AREAS.
KEPT POPS THROUGH THE NIGHT DUE TO THE COLD FRONT.
THE FRONT WILL SETTLE OVER THE REGION ON TUE AND THE FLOW WILL
TURN E. HAD MAINLY ISOLATED POPS THROUGH THE DAY. STRONG THETA-E
RIDGE WILL HELP CONTINUE CHANCES FOR THUNDERSTORMS TUE NIGHT. TUE
WILL BE COOLER WITH READINGS IN THE 80S BUT A THERMAL RIDGE WILL
KEEP THE E WARMER WITH TEMPERATURES AROUND 90. ARTHUR
.LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN...
THE THEME IN THE EXTENDED FORECAST REMAINS SUMMER TEMPERATURES AND
ISOLATED TO SCATTERED THUNDERSTORMS EACH DAY. BROAD SUMMER RIDGING
WILL FINALLY BE ESTABLISHED ACROSS MOST OF THE CONUS WITH THE
FORECAST AREA REMAINING ON THE NORTHERN EXTENT OF THE RIDGE WITH
THE JET STREAM NEARBY TO THE NORTH.
THIS SETUP WILL ALLOW INCREASING MID-LEVEL MOISTURE ACROSS THE
FORECAST AREA FROM THE MONSOONAL FLOW OUT OF THE SOUTH.
FURTHERMORE...LOW-LEVEL MOISTURE WILL BE ON THE INCREASE THANKS TO
GULF MOISTURE BEING TRANSPORTED UP THE GREAT PLAINS AND INTO THE
FORECAST AREA FROM THE EAST AND NORTHEAST. THIS WILL KEEP PW
VALUES RUNNING BETWEEN 1 AND 1.5 INCHES ACROSS THE FORECAST AREA
WEDNESDAY THROUGH FRIDAY. THESE WILL BE THE BEST DAYS IN THE
EXTENDED FORECAST FOR THUNDERSTORM ACTIVITY. DEEP LAYER SHEER
(0-6KM) SHOULD BE WEAK ON WEDNESDAY AS THE JET STREAM REMAINS
MOSTLY NORTH OF THE FORECAST AREA...THUS EXPECT STORMS TO BE HEAVY
RAINERS BUT THE SEVERE POTENTIAL SHOULD BE VERY LIMITED. DEEP
LAYER SHEER SHOULD INCREASE TO AROUND 40 KTS FOR THURSDAY AND
FRIDAY AS THE JET SAGS FARTHER SOUTH. THIS WILL BE COUPLED WITH
COOLER 700 MB TEMPERATURES. THUS EXPECT THUNDERSTORMS ON THURSDAY
AND FRIDAY COULD BE ON THE STRONG SIDE WITH SOME ISOLATED SEVERE
POTENTIAL.
STRONGER ZONAL TO NORTHWESTERLY FLOW ESTABLISHES OVER THE FORECAST
AREA BY THE WEEKEND. THIS HELPS TO KEEP MONSOONAL MOISTURE LOCKED
TO THE SOUTH OF THE FORECAST AREA WHILE THE LOW-LEVEL MOISTURE
BECOMES SHIFTED TO THE EAST. THIS SHOULD MINIMIZED OUR CHANCES OF
PRECIPITATION THIS WEEKEND.
TEMPERATURES WILL REMAIN JUST ABOVE SEASONAL NORMALS IN THE UPPER
80S AND LOW 90S THROUGH THE EXTENDED FORECAST.
CHURCH
&&
.AVIATION...
SCATTERED SHOWERS AND THUNDERSTORMS WILL BE STRONGEST SOUTH OF
KBIL THIS AFTERNOON AND EVENING. BRIEF MVFR CONDITIONS ARE
POSSIBLE WITH THE STRONGEST CELLS ALONG WITH GUSTY WINDS. EXPECT
CLEARING CONDITIONS AFTER MIDNIGHT. BORSUM
&&
.PRELIMINARY POINT TEMP/POPS...
MON TUE WED THU FRI SAT SUN
-----------------------------------------------------------
BIL 061/095 064/083 062/090 066/092 065/093 065/094 065/094
32/T 22/T 32/T 32/T 33/T 31/B 11/B
LVM 052/091 054/085 056/091 055/092 056/093 052/095 052/095
43/T 33/T 33/T 33/T 33/T 32/T 21/B
HDN 061/096 062/087 058/092 061/093 063/093 061/095 061/096
42/T 22/T 32/T 32/T 32/T 21/B 11/B
MLS 065/095 067/089 064/093 068/093 066/093 067/094 066/094
22/T 22/T 22/T 22/T 22/T 21/B 11/U
4BQ 062/093 062/092 061/093 063/091 065/090 061/092 060/093
43/T 22/T 21/U 12/T 22/T 21/B 11/U
BHK 060/087 062/088 059/091 064/090 064/088 062/089 061/090
43/T 22/T 21/B 22/T 22/T 22/T 21/U
SHR 058/091 058/089 058/092 058/091 058/090 057/092 057/094
42/T 22/T 22/T 22/T 33/T 31/B 11/U
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
942 AM MDT SUN JUL 14 2013
.UPDATE...
ADJUSTED POPS A LITTLE TODAY FOR THE MORNING UPDATE. TWO AREAS OF
CONCERN ON RADAR THIS MORNING. FIRST WAS THE ISOLATED
THUNDERSTORMS OVER THE EASTERN PART OF THE AREA DUE TO 850-700
FRONT AND ELEVATED INSTABILITY. THIS FRONT GRADUALLY DISSOLVES
THIS AFTERNOON. A WARM FRONT WAS TAKING SHAPE SW OF THE REGION
THIS MORNING. THE WARM FRONT WAS COMBINING WITH LIFT FROM A
SHORTWAVE OVER N ID...SEEN ON WATER VAPOR IMAGERY...TO BRING A
FEW SHOWERS TO SW MT ON RADAR. THESE SHOWERS WERE MOVING NE TOWARD
THE FORECAST AREA. AS THE DAY PROGRESSES...STRONG ISENTROPIC LIFT
WILL DEVELOP ON THE NORTHWARD MOVING WARM FRONT OVER THE S CENTRAL
PART OF THE AREA. HAVE INCREASED POPS IN THIS REGION THIS
AFTERNOON AND EVENING. ADDED POPS TO THE SW THIS MORNING AS WELL.
THE E WILL HAVE LOW POPS DUE TO THIS MORNING/S 850-700 MB FRONT
AND THE APPROACHING WARM FRONT. A WEAKER WAVE WILL MOVE INTO THE
SW THIS AFTERNOON ADDING TO LIFT OVER THE AREA AS WELL.
PRECIPITABLE WATERS WILL REMAIN NEAR AN INCH OVER THE AREA WHICH
WILL ALLOW THUNDERSTORMS TO PRODUCE HEAVY RAINFALL ONCE AGAIN.
WRF HAD DECENT INSTABILITY OF 500-1000 J/KG OF CAPE OVER THE
CENTRAL ZONES...WHILE RAP HAD AROUND 500 J/KG W AND CENTRAL. THERE
WAS ALSO SOME DECENT SHEAR OVER THE AREA. SOME STORMS COULD BECOME
STRONG W AND CENTRAL LATE TODAY INTO THE EVENING. THE E WILL BE
CAPPED BUT LIFT SHOULD BE ABLE TO TAP THE ELEVATED INSTABILITY TO
SUPPORT THUNDER. TEMPERATURES IN THE 70S AND 80S WERE ON TRACK.
ARTHUR
&&
.SHORT TERM...VALID FOR TDY AND MON...
SYNOPSIS...WEAK FORCING WILL HOLD STRONG THUNDERSTORM POTENTIAL DOWN
DESPITE UPSLOPE WINDS AND PLENTY OF MOISTURE IN PLACE THE NEXT
COUPLE OF DAYS. COLD FRONT PUSHED THROUGH THE AREA BY EARLY LAST
EVENING WITH ELEVATED 700MB FRONTOGENESIS BAND STILL GENERATING
SCATTERED SHOWER BANDS OVER EASTERN HALF OF THE FORECAST AREA.
SURFACE HIGH OVER SOUTHERN SASKATCHEWAN WILL SHIFT SOUTHEAST TODAY
TURNING LOW LEVEL WINDS EASTERLY. THIS WILL ADVECT IN HIGHER
DEWPOINT AIR AND PROVIDE LIFT INTO AREA FOOTHILLS/MOUNTAINS VIA
UPSLOPE GRADIENT.BY THIS EVENING WINDS WILL BEGIN TO TURN
SOUTHERLY OVER WESTERN AREAS AS LEE SIDE TROFING BEGINS TO
DEVELOP. THIS WILL ALLOW HOTTER AND DRIER AIR FROM THE GREAT BASIN
TO SPILL BACK INTO THE AREA FOR MONDAY. NOT MUCH IN THE WAY OF
FORCING ON MONDAY BUT HOT TEMPERATURES OVER THE HIGHER TERRAIN
SHOULD BE ENOUGH FOR ISOLATED TO SCATTERED HIGH BASED
THUNDERSTORMS...THOUGH VERY WARM 700MB TEMPERATURES WILL LIKELY
PREVENT STORMS FROM MAINTAINING OVER THE LOWER ELEVATIONS. ANOTHER
PACIFIC DISTURBANCE WILL SLIDE EASTWARD ALONG THE CANADIAN BORDER
MONDAY NIGHT. THIS WILL PUSH A COLD FRONT THROUGH THE AREA
OVERNIGHT PROVIDING FOCUS FOR ADDITIONAL SHOWER AND THUNDERSTORM
DEVELOPMENT INTO TUESDAY.
TODAY...700 MB FRONTOGENESIS BAND COMBINED WITH A VERY WEAK
DISTURBANCE SLIDING NORTHEAST OUT OF WYOMING WILL PROVIDE LIFT
OVER SOUTHEAST MONTANA THIS MORNING. MODELS PRETTY BULLISH ON
SCATTERED SHOWERS/THUNDESTORMS OVER THIS AREA THROUGH THE MORNING
HOURS AND HAVE KEPT 40 TO 50 POPS IN PLACE. DESPITE PRECIPITABLE
WATER VALUES IN THE 1.2 TO 1.4 INCH RANGE HAVE KEPT MENTION OF
HEAVY RAIN OUT OF THE FORECAST FOR NOW BASED ON LACK OF STRONGER
FORCING MECHANISM FOR DEEP CONVECTION...BUT LOCALLY HEAVY RAINFALL
IS NOT OUT OF THE QUESTION EAST OF A MILES CITY TO SHERIDAN LINE
TODAY. LATER THIS AFTERNOON EXPECT DIURNAL INSTABILITY TO COMBINE
WITH EASTERLY LOW LEVEL WINDS TO PRODUCE SCATTERED SHOWERS AND
THUNDERSTORMS OVER EAST/NORTH FACING SLOPES OF AREA MOUNTAINS.
STORMS WILL DRIFT NORTHEAST AND SHOULD PERSIST WELL INTO THE
EVENING WITH AN ASSIST FROM A WEAK UPPER WAVE EMBEDDED IN THE FLOW
ALOFT. ONCE HEATING DECLINES DURING THE MID TO LATE EVENING HOURS
WILL SEE CONVECTION DISSIPATE WITH JUST A FEW LINGERING CELLS
OVERNIGHT OVER EASTERN AREAS AS THE UPPER WAVE PUSHES THROUGH.
TEMPERATURES IN THE MID 80S SEEM REASONABLE FOR MOST AREAS TODAY
WITH EASTERLY LOW LEVEL WINDS LIMITING MIXING.
MONDAY...OVERNIGHT WILL SEE LOW TO MID LEVEL WARM ADVECTION KICK
IN AS SURFACE WINDS TURN SOUTHWESTERLY DUE TO LEE SIDE TROFING AND
MID LEVELS WARM IN ADVANCE OF NEXT PACIFIC TROF. THIS WARMING AND
DRYING WILL ALLOW TEMPERATURES TO REBOUND INTO THE MID 90S FOR
MOST LOCATIONS MONDAY AFTERNOON. WITH TEMPERATURES IN THE 90S AND
PLENTY OF LOW LEVEL MOISTURE IN PLACE EAST OF A ROUNDUP TO
BILLINGS LINE SHOULD SEE CAPE VALUES OVER 1000 J/KG DURING THE
AFTERNOON WITH DECENT SHEAR PROFILES. HOWEVER CAPPING INVERSION
AND LACK OF ANY FORCING WILL LIKELY KEEP A LID ON STORMS MONDAY
AFTERNOON IN THESE AREAS AND HAVE KEPT JUST A 20 PERCENT CHANCE IN
THE FORECAST IN CASE A FEW CELLS ARE ABLE TO BREAK THE CAP...AND
LEFT ANY MENTION OF STRONG STORMS OUT OF THE FORECAST FOR THESE
REASONS AS WELL. WEST OF THE ROUNDUP TO BILLINGS LINE MOISTURE
WILL BE MORE LIMITED AS SOUTHWESTERLY WINDS MIX LOW LEVEL MOISTURE
OUT IN THE AFTERNOON. THERE IS NOT MUCH IN THE WAY OF FORCING TO
GENERATE CONVECTION...HOWEVER WITH THE EXPECTED HOT TEMPERATURES
SHOULD BE ABLE TO GENERATE HIGH BASED CONVECTION OVER THE
MOUNTAINS. THIS CONVECTION WILL LIKELY PRODUCE MORE WIND GUSTS
THAN RAIN AND IT WILL HAVE A HARD TIME SUSTAINING OUT INTO THE
PLAINS DUE TO +14C AIR AT 700MB.
COLD FRONT LATE MONDAY NIGHT IS PROBABLY THE BEST CHANCE FOR
PRECIPITATION DURING THIS PERIOD. ONCE AGAIN THE BEST FORCING
WITH THIS SYSTEM WILL REMAIN WELL TO THE NORTH OF THE AREA SO
LIMITED SHOWERS AND THUNDERSTORM TO ISOLATED/SCATTERED COVERAGE.
HOWEVER MOISTURE ADVECTION INTO THE FRONT AND STRENGTH OF THE
FRONTAL PUSH SHOULD PROVIDE SOME AREAS WITH A CHANCE AT A TENTH
OR MORE OF PRECIPITATION OVERNIGHT. CHAMBERS
.LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT...
HEIGHTS WILL BEGIN TO REBOUND TUESDAY IN THE WAKE OF SHORTWAVE
ACROSS SOUTHERN CANADA...THE FEATURE CURRENTLY DROPPING THROUGH
BRITISH COLUMBIA. STRONGLY CONFLUENT FLOW OVER THE REGION SUPPORTS
LEE SIDE SFC RIDGING ON TUE...AND THE LATEST MODEL RUNS HAVE
TRENDED A BIT STRONGER WITH THIS RIDGE AND RESULTANT LOW LEVEL
COOLING IN SOUTHEAST MT...ESPECIALLY IN OUR WESTERN UPSLOPE AREAS.
HAVE DROPPED EXPECTED HIGH TEMPS IN OUR WEST BUT HAVE NOT GONE AS
LOW AS GUIDANCE PER THE 590ISH HEIGHTS BUILDING IN. ALSO...DESPITE
THE LOW LEVEL STABILIZING...ELEVATED INSTABILITY SHOULD REMAIN...
AND WITH WEAK ENERGY LIFTING OUT OF THE GREAT BASIN CANNOT
DISCOUNT SOME SHOWER OR WEAK TSTM ACTIVITY TUESDAY INTO TUESDAY
NIGHT. OVERALL AN INTERESTING WEATHER DAY.
UPPER RIDGE WILL DOMINATE THE REGION THROUGH THE END OF THE WEEK
BUT PERHAPS NOT AS STRONGLY AS PREVIOUSLY THOUGHT...ESPECIALLY AS
PACIFIC ENERGY MAY BEGIN TO SUPPRESS HEIGHTS FURTHER BY NEXT
WEEKEND. PRECIPITABLE WATERS WILL BE QUITE HIGH WED/THU/FRI...A
RESULT OF EASTERLY LOW LEVEL WINDS AND MONSOONAL FLOW FROM THE
GREAT BASIN. CONVECTION WILL FIRE OVER THE HIGH TERRAIN EACH OF
THESE DAYS AND HAVE RAISED POPS TO ABOVE CLIMATOLOGY BASED ON THE
MOISTURE THAT WILL BE PRESENT. A FEW STORMS MAY DRIFT OVER THE
PLAINS BUT THEY SHOULD BE LARGELY UNORGANIZED. THIS CONVECTION
WILL BE IN WEAK SHEAR ENVIRONMENTS AND BATTLE WARM MID LEVEL
TEMPS SO DO NOT SEE A SEVERE RISK...BUT COULD BE SOME HEAVY RAIN
GIVEN THE MOISTURE AND WHAT SHOULD BE SLOW MOVING STORMS. PACIFIC
FLOW MAY INCREASE BY NEXT WEEKEND AND ALLOW FOR A BIT DRIER AIR TO
ADVECT FROM THE WEST...SO WILL KEEP THE FORECAST MOSTLY DRY NEXT
SAT/SUN. TEMPS SHOULD REMAIN ABOVE NORMAL BUT NOT DRAMATICALLY
SO...WITH HIGHS GENERALLY IN THE UPPER 80S TO MID 90S. MODELS HAVE
ACTUALLY TRENDED A BIT COOLER...AGAIN PER THE RIDGE BEING NOT
QUITE AS STRONG...SO HAVE TWEAKED TEMPS DOWN SLIGHTLY FOR SOME
PERIODS.
JKL
&&
.AVIATION...
EXPECT SHOWERS AND THUNDERSTORMS TO DEVELOP THIS AFTERNOON WITH
LOCAL MVFR POSSIBLE IN HEAVY DOWNPOURS. BORSUM
&&
.PRELIMINARY POINT TEMP/POPS...
TDY MON TUE WED THU FRI SAT
-------------------------------------------------------
BIL 084 061/094 065/084 061/090 066/092 065/093 065/094
3/T 22/T 22/T 22/T 22/T 22/T 21/B
LVM 084 052/090 053/085 054/091 055/092 056/093 052/095
4/T 43/T 33/T 33/T 33/T 32/T 22/T
HDN 084 061/096 062/087 059/092 061/093 063/093 061/095
4/T 22/T 22/T 22/T 22/T 22/T 21/B
MLS 082 065/095 068/089 063/093 068/093 066/093 067/094
3/T 22/T 22/T 22/T 22/T 22/T 21/B
4BQ 082 062/093 063/091 060/093 063/091 065/090 061/092
3/T 32/T 22/T 21/U 12/T 22/T 21/B
BHK 078 060/089 064/088 061/091 064/090 064/088 062/089
3/T 22/T 22/T 21/B 22/T 22/T 22/T
SHR 083 058/091 058/089 058/092 058/091 058/090 057/092
4/T 42/T 22/T 22/T 22/T 23/T 31/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
1148 PM MDT SAT JUL 13 2013
.AVIATION...
06Z TAF CYCLE
A FEW SHOWERS AND THUNDERSTORMS TO IMPACT KABQ AND KSAF THROUGH 08Z.
BUT VFR CONDITIONS WILL PREVAIL THROUGH 18Z SUNDAY. ANOTHER ROUND
OF SHOWERS AND STORMS SUNDAY AFTERNOON WITH MAIN FOCUS ON THE
NORTHERN MOUNTAINS AND NORTHEAST AS A STRONG BACK DOOR COLD FRONT
MOVES INTO THESE AREAS. BRIEF MVFR TO IFR CONDITIONS FROM THE
STRONGER THUNDERSTORMS. STRONG EAST CANYON WINDS LIKELY SUNDAY
NIGHT INTO THE RIO GRANDE VALLEY WITH GUSTS AROUND 40 KTS. STRONG
MOISTURE PUSH INTO THE EAST AS WELL SUNDAY NIGHT. CHJ
&&
.PREV DISCUSSION...1039 PM MDT SAT JUL 13 2013...
QUICK UPDATE TO TWEAK POPS TO REFLECT CURRENT TRENDS. LOOKS LIKE
MUCH OF THE ACTIVITY FOR THE REMAINDER OF THE EVENING WILL BE OVER
OR NEAR THE RIO GRANDE VALLEY. THE HRRR CORROBORATES THIS WELL.
OTHERWISE...MADE SOME MINOR TWEAKS TO QPF AND SKY. UPDATES ALREADY
OUT. 34
.PREV DISCUSSION...322 PM MDT SAT JUL 13 2013...
STARTING BACK ON SHIFT AFTER WEEK AND A HALF ABSENCE...SO HAVE
BEEN DIGESTING THE RATHER BIZARRE PATTERN SHIFT UPCOMING. DECENT
CROP OF SCATTERED SHOWERS AND STORMS GOING THIS AFTN...BUT THE
SACRAMENTOS HAVE OPTED OUT SO FAR. SO ONCE AGAIN THE WEST IS BEST
AND EAST IS LEAST WITH REGARDS TO CONVECTION AND TREND SHOULD
CONTINUE INTO THE EVE. SHOULD FOR THE MOST PART SEE THE ACTIVITY
DIMINISHING LATER ON THIS EVE AND OVERNIGHT...BUT AS WITH LAST
NIGHT A FEW LOCALES IN THE CENTRAL...WEST AND NORTH MAY FIRE UP
WITH ISOLATED CELLS LATE TONIGHT...MORE LIKELY THOSE THAT HAD
LITTLE ACTION DURING THE DAY OR EARLY EVE AND HAVE SOME LEFTOVER
BOUNDARY INTERACTIONS.
NOW ONTO THE CHANGES THAT THIS FCSTR HAS NOT SEEN...AT LEAST NOT
TO ANYWHERE NEAR THIS DEGREE...SINCE GETTING HERE NEARLY 20 YEARS
AGO. NAMELY THE FAIRLY RAPID WESTWARD PROGRESSION OF A NON-
TROPICAL WELL DEVELOPED MID AND UPPER LVL LOW NOW OVER THE WESTERN
OHIO VALLEY. IT IS FAIRLY INACTIVE IN TERMS OF PCPN CURRENTLY...
BUT THERE IS A DISTURBANCE AND SLUG OF MOISTURE TO ITS NW AND
PRETTY DECENT LOW LVL MOISTURE WHICH WILL BE DRAWN UP ON ITS EAST
SIDE...ESPECIALLY AS IT REACHES THE OK N TX REGION LATER SUN.
MODELS PRETTY CONSISTENT STILL PINWHEELING THAT DISTURBANCE...AND
MOISTURE...INTO AND ACROSS NM FROM NE TO SW LATER SUN INTO MON.
BUT ALSO IT WILL DRAW TERRAIN INDUCED CONVECTION SOUTHWARD FROM
THE HIGHER MTNS OF CO INTO THE STATE AS WELL AS UPSLOPE INDUCED
RAINS FROM E CO AND NE NM SOUTHWARD ACROSS THE AREA. SO WHILE
THERE WILL BE QUITE A LOT OF CLOUD COVER TO DEAL WITH...THE ADDED
UPPER LEVEL DYNAMICS...AFOREMENTIONED UPSLOPE AND OVERALL
SIGNIFICANT MOISTURE INCREASE THOUGHT THE ATMOSPHERIC COLUMN
SHOULD ACT TO KEEP AT LEAST SOME CONVECTION GOING ALONG WITH AREAS
OR MORE STRATIFORM RAINS. WILL BE LOOKING AT A LIKELY UPSWING IN
FLASH FLOOD POTENTIAL LATE SUN INTO AT LEAST TUE FOR CENTRAL MTN
CHAIN EAST AT LEAST TO THE ADJACENT HIGHLANDS AND HIGH PLAINS TO
THE EAST...DUE LARGELY TO UPSLOPE EFFECTS AND MIX OF CONVECTIVE
AND STRATIFORM PCPN...THEN AT LEAST MON AND TUE FROM THE DIVIDE
PERHAPS AS FAR EAST AS WEST EDGE OF RIO GRANDE VALLEY. SOME
MODERATE TO PERHAPS STRONG EAST WINDS INTO RIO GRANDE VALLEY
ITSELF MAY HAVE SOME NEGATIVE IMPACTS ON RAINFALL AMTS IN PORTIONS
OF THE VALLEY...BUT ALL IN ALL THIS SYSTEM SHOULD REALLY DO A LOT
FOR WATERING THE GAPS IN PCPN COVERAGE SO FAR SEEN SINCE THE ONSET
OF THE RECENT SCATTERED RAINFALL. WILL BE LOOKING AT A POSS FLASH
FLOOD WATCH ISSUANCE IN NEXT 1 TO 3 SHIFTS...BUT FOR NOW WILL GO
WITH A SPECIAL WX STATEMENT ADDRESSING THIS POTENTIAL. 43
&&
.FIRE WEATHER...
WET WEATHER PATTERN TO ENSUE BEGINNING SUNDAY EVENING THROUGH AT
LEAST THE MIDDLE OF NEXT WEEK. AS A RESULT...NO FIRE WEATHER
CONCERNS THROUGH THE MIDDLE OF NEXT WEEK...THE COMBINATION OF
CONTINUED MONSOONAL MOISTURE FLOW INTO THE REGION AND A WESTWARD
MOVING UPPER LOW. TEMPERATURES WILL BE BELOW SIGNIFICANTLY NORMAL
MONDAY TO THURSDAY WITH MORE WIDESPREAD STORMS...WETTING RAINS AND
CLOUDINESS.
RH RECOVERIES WILL GOOD TOMORROW THEN EXCELLENT MONDAY THROUGH
THURSDAY. FRIDAY AND SATURDAY RH RECOVERIES WILL BE GOOD AS AIRMASS
DRYING IS EXPECT AS THE UPPER LOW RETREATS SOUTH INTO NORTHERN
MEXICO. WIND CONCERNS MOSTLY WITH THUNDERSTORM OUTFLOWS DURING THE
PERIOD EXCEPT FOR AN EASTERLY GAP/CANYON WINDS THAT WILL DEVELOP
SUNDAY NIGHT THROUGH MONDAY MORNING AND LIKELY AGAIN MONDAY NIGHT TO
EARLY TUESDAY. THESE GUSTY WINDS WILL BE STRONGEST DOWNWIND OF
CENTRAL GAPS/CANYONS AS SYNOPTIC EASTERLY FLOW DEVELOPS BENEATH THE
APPROACHING UPPER LOW. LOWER MIXING HEIGHTS EXPECTED WITH THIS
COOLER/MOIST AIRMASS. NO WIDESPREAD VENTILATION ISSUES EXPECTED FOR
THE UPCOMING WEEK. 01
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
40
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1039 PM MDT SAT JUL 13 2013
.UPDATE...
QUICK UPDATE TO TWEAK POPS TO REFLECT CURRENT TRENDS. LOOKS LIKE
MUCH OF THE ACTIVITY FOR THE REMAINDER OF THE EVENING WILL BE OVER
OR NEAR THE RIO GRANDE VALLEY. THE HRRR CORROBORATES THIS WELL.
OTHERWISE...MADE SOME MINOR TWEAKS TO QPF AND SKY. UPDATES ALREADY
OUT. 34
&&
.PREV DISCUSSION...657 PM MDT SAT JUL 13 2013...
.AVIATION...
00Z TAF CYCLE
EVENING SHOWERS AND THUNDERSTORMS TO MAINLY IMPACT KGUP WHILE
HOLDING ONTO VCTS AT KFMN...KSAF AND KABQ THROUGH 02Z OR 03Z.
VCSH THROUGH ABOUT 06Z AT ABOVE LISTED TAFS. BRIEF MVFR VISIBILITY
FROM ANY THUNDERSTORM THIS EVENING...OTHERWISE VFR CONDITIONS
THROUGH 18Z SUNDAY. ANOTHER ROUND OF SHOWERS AND STORMS SUNDAY
AFTERNOON WITH MAIN FOCUS ON THE NORTHERN MOUNTAINS AND NORTHEAST
AS A STRONG BACK DOOR COLD FRONT MOVES INTO THESE AREAS. CHJ
.PREV DISCUSSION...322 PM MDT SAT JUL 13 2013...
STARTING BACK ON SHIFT AFTER WEEK AND A HALF ABSENCE...SO HAVE
BEEN DIGESTING THE RATHER BIZARRE PATTERN SHIFT UPCOMING. DECENT
CROP OF SCATTERED SHOWERS AND STORMS GOING THIS AFTN...BUT THE
SACRAMENTOS HAVE OPTED OUT SO FAR. SO ONCE AGAIN THE WEST IS BEST
AND EAST IS LEAST WITH REGARDS TO CONVECTION AND TREND SHOULD
CONTINUE INTO THE EVE. SHOULD FOR THE MOST PART SEE THE ACTIVITY
DIMINISHING LATER ON THIS EVE AND OVERNIGHT...BUT AS WITH LAST
NIGHT A FEW LOCALES IN THE CENTRAL...WEST AND NORTH MAY FIRE UP
WITH ISOLATED CELLS LATE TONIGHT...MORE LIKELY THOSE THAT HAD
LITTLE ACTION DURING THE DAY OR EARLY EVE AND HAVE SOME LEFTOVER
BOUNDARY INTERACTIONS.
NOW ONTO THE CHANGES THAT THIS FCSTR HAS NOT SEEN...AT LEAST NOT
TO ANYWHERE NEAR THIS DEGREE...SINCE GETTING HERE NEARLY 20 YEARS
AGO. NAMELY THE FAIRLY RAPID WESTWARD PROGRESSION OF A NON-
TROPICAL WELL DEVELOPED MID AND UPPER LVL LOW NOW OVER THE WESTERN
OHIO VALLEY. IT IS FAIRLY INACTIVE IN TERMS OF PCPN CURRENTLY...
BUT THERE IS A DISTURBANCE AND SLUG OF MOISTURE TO ITS NW AND
PRETTY DECENT LOW LVL MOISTURE WHICH WILL BE DRAWN UP ON ITS EAST
SIDE...ESPECIALLY AS IT REACHES THE OK N TX REGION LATER SUN.
MODELS PRETTY CONSISTENT STILL PINWHEELING THAT DISTURBANCE...AND
MOISTURE...INTO AND ACROSS NM FROM NE TO SW LATER SUN INTO MON.
BUT ALSO IT WILL DRAW TERRAIN INDUCED CONVECTION SOUTHWARD FROM
THE HIGHER MTNS OF CO INTO THE STATE AS WELL AS UPSLOPE INDUCED
RAINS FROM E CO AND NE NM SOUTHWARD ACROSS THE AREA. SO WHILE
THERE WILL BE QUITE A LOT OF CLOUD COVER TO DEAL WITH...THE ADDED
UPPER LEVEL DYNAMICS...AFOREMENTIONED UPSLOPE AND OVERALL
SIGNIFICANT MOISTURE INCREASE THOUGHT THE ATMOSPHERIC COLUMN
SHOULD ACT TO KEEP AT LEAST SOME CONVECTION GOING ALONG WITH AREAS
OR MORE STRATIFORM RAINS. WILL BE LOOKING AT A LIKELY UPSWING IN
FLASH FLOOD POTENTIAL LATE SUN INTO AT LEAST TUE FOR CENTRAL MTN
CHAIN EAST AT LEAST TO THE ADJACENT HIGHLANDS AND HIGH PLAINS TO
THE EAST...DUE LARGELY TO UPSLOPE EFFECTS AND MIX OF CONVECTIVE
AND STRATIFORM PCPN...THEN AT LEAST MON AND TUE FROM THE DIVIDE
PERHAPS AS FAR EAST AS WEST EDGE OF RIO GRANDE VALLEY. SOME
MODERATE TO PERHAPS STRONG EAST WINDS INTO RIO GRANDE VALLEY
ITSELF MAY HAVE SOME NEGATIVE IMPACTS ON RAINFALL AMTS IN PORTIONS
OF THE VALLEY...BUT ALL IN ALL THIS SYSTEM SHOULD REALLY DO A LOT
FOR WATERING THE GAPS IN PCPN COVERAGE SO FAR SEEN SINCE THE ONSET
OF THE RECENT SCATTERED RAINFALL. WILL BE LOOKING AT A POSS FLASH
FLOOD WATCH ISSUANCE IN NEXT 1 TO 3 SHIFTS...BUT FOR NOW WILL GO
WITH A SPECIAL WX STATEMENT ADDRESSING THIS POTENTIAL.
43
.FIRE WEATHER...
WET WEATHER PATTERN TO ENSUE BEGINNING SUNDAY EVENING THROUGH AT
LEAST THE MIDDLE OF NEXT WEEK. AS A RESULT...NO FIRE WEATHER
CONCERNS THROUGH THE MIDDLE OF NEXT WEEK...THE COMBINATION OF
CONTINUED MONSOONAL MOISTURE FLOW INTO THE REGION AND A WESTWARD
MOVING UPPER LOW. TEMPERATURES WILL BE BELOW SIGNIFICANTLY NORMAL
MONDAY TO THURSDAY WITH MORE WIDESPREAD STORMS...WETTING RAINS AND
CLOUDINESS.
RH RECOVERIES WILL GOOD TOMORROW THEN EXCELLENT MONDAY THROUGH
THURSDAY. FRIDAY AND SATURDAY RH RECOVERIES WILL BE GOOD AS AIRMASS
DRYING IS EXPECT AS THE UPPER LOW RETREATS SOUTH INTO NORTHERN
MEXICO. WIND CONCERNS MOSTLY WITH THUNDERSTORM OUTFLOWS DURING THE
PERIOD EXCEPT FOR AN EASTERLY GAP/CANYON WINDS THAT WILL DEVELOP
SUNDAY NIGHT THROUGH MONDAY MORNING AND LIKELY AGAIN MONDAY NIGHT TO
EARLY TUESDAY. THESE GUSTY WINDS WILL BE STRONGEST DOWNWIND OF
CENTRAL GAPS/CANYONS AS SYNOPTIC EASTERLY FLOW DEVELOPS BENEATH THE
APPROACHING UPPER LOW. LOWER MIXING HEIGHTS EXPECTED WITH THIS
COOLER/MOIST AIRMASS. NO WIDESPREAD VENTILATION ISSUES EXPECTED FOR
THE UPCOMING WEEK. 01
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1006 PM CDT MON JUL 15 2013
.UPDATE...
ISSUED AT 1004 PM CDT MON JUL 15 2013
RAIN BAND DISSIPATED ON SCHEDULE FAR-BJI SO NOW HAVE REMOVED ANY
PRECIP FROM FCST THAT REGION TONIGHT. ONLY WATCHING BAND OF STORMS
IN NW ND...SEEMS TO BE ENOUGH INSTABILITY AND LOW LEVEL JET OVER
CNTRL ND TO FEED THIS LINE....THOUGH NOT LIKELY SEVERE...INTO THE
OVERNIGHT. LATEST HRRR STILL SHOWS SOME PRECIP INTO DVL BASIN NR
6-7Z AND THEN DISSIPATING INTO THE RRV.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 304 PM CDT MON JUL 15 2013
CONVECTION CHANCES WILL BE THE MAIN CHALLENGE THROUGHOUT THE
PERIOD.
THE UPPER RIDGE OVER THE EASTERN CONUS CONTINUES TO BUILD INTO THE
CENTRAL PART OF THE CONUS...WITH A SHORTWAVE TROUGH OVER SASK THAT
SHOULD MOVE THROUGH SOUTHERN CANADA TONIGHT. RAIN SHOWERS HAVE
CONTINUED IN A BAND ALONG AN OLD FRONTAL BOUNDARY FROM THE
SOUTHWESTERN CWA TO FARGO AND PARK RAPIDS. SHORT RANGE MODELS ALL
HAVE THIS BAND OF RAIN SLOWLY LIFTING NORTH FOR THE REST OF THE
AFTERNOON BEFORE DISSIPATING THIS EVENING AS THE FRONT WASHES OUT.
WITH INSTABILITY LIMITED BY THE CLOUDS AND RAIN FOR MUCH OF THE
DAY...SHOWERS WITH ONLY AN ISOLATED THUNDER MENTION SEEM
REASONABLE. THE NEXT CHANCE FOR PRECIP WILL ARRIVE IN OUR
NORTHWESTERN CWA LATER TONIGHT AS THE SHORTWAVE OVER CANADA MOVES
EAST AND HELPS PUSH A TROUGH AXIS INTO CENTRAL ND. THINK THAT MOST
ACTIVITY WILL BE OVER THE WESTERN PART OF THE STATE BUT SOME COULD
HOLD TOGETHER LONG ENOUGH TO IMPACT THE DEVILS LAKE BASIN SO KEPT
AROUND 30 POPS THERE.
THE UPPER RIDGE WILL CONTINUE TO BUILD WESTWARD THROUGH
TOMORROW...WITH THE MAIN WESTERLIES LIFTING JUST TO OUR NORTH.
MODELS ARE ALL IN PRETTY DECENT AGREEMENT ON DROPPING A WEAK COLD
FRONT INTO THE CWA AND STALLING IT OUT...ALTHOUGH THERE ARE
DIFFERENCES IN EXACTLY WHERE IT SETS UP. MOST SEEM TO STALL THE
BOUNDARY OVER THE NORTHERN TO CENTRAL CWA...AND WITH MOISTURE AND
INSTABILITY POOLING ON THE NORTH SIDE OF THE BOUNDARY...IT COULD
BE A FOCUS FOR CONVECTION TUESDAY AFTERNOON AND EVENING. DEEP
LAYER SHEAR IS NOT HUGELY IMPRESSIVE SO ANY SEVERE WILL BE
ISOLATED AT BEST. THE FRONT WILL CONTINUE TO WOBBLE OVER THE AREA
THROUGH TUESDAY NIGHT...SO CONTINUED TO KEEP POPS GOING FOR OUR
NORTHERN COUNTIES.
AS FOR TEMPERATURES...MUCH WILL DEPEND ON EXACTLY HOW CLOUDS AND
PRECIP PLAY OUT. FOR NOW KEPT LOWS MAINLY IN THE 60S AND HIGHS IN
THE UPPER 70S TO 80S...WITH HIGHEST VALUES IN THE SOUTHERN CWA
AND COOLEST IN THE NORTH WHERE THE FRONTAL BOUNDARY AS WELL AS
CLOUDS ARE MOST LIKELY TO BE FOUND.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 304 PM CDT MON JUL 15 2013
WEDNESDAY...THE MODELS SHOW SOME INDICATION OF THE FRONT SAGGING
SOUTH A LITTLE BIT. CONTINUED TO KEEP SCATTERED POPS GOING A BIT
FURTHER SOUTH THAN TUESDAY. THINK A MORE SIGNIFICANT CHANCE FOR
CONVECTION WILL ARRIVE ON THURSDAY AS 500MB HEIGHTS BEGIN TO FALL
ACROSS THE AREA AS A SHORTWAVE TROUGH DIGS INTO SOUTHERN CANADA.
THE SFC FRONT WILL LIFT BACK NORTH A BIT...AND THEN DROP SOUTH AS
A COLD FRONT BY LATE THURSDAY. WITH THE MAIN WESTERLIES BACK OVER
THE AREA...DEEP LAYER SHEAR WILL BE AROUND 40-50 KTS AND MODELS
SHOW SOME STRONG INSTABILITY NEAR THE BOUNDARY. KEPT CHANCES FOR
THUNDERSTORMS HIGH FOR THURSDAY.
FOR THURSDAY NIGHT THROUGH MONDAY THE REGION WILL ESSENTIALLY
REMAIN IN NORTHWEST FLOW ALOFT. LOOKS LIKE THERE COULD BE SUBTLE
WAVES IN THE FLOW WHICH COULD HELP INITIATE SOME LOW END
CONVECTIVE CHANCES THU THROUGH SUN. BETTER CHANCES FOR PCPN MAY
COME WITH A STRONGER WAVE AND FRONT SOMETIME ON MONDAY ALTHOUGH
MODELS ARE NOT IN VERY GOOD AGREEMENT BY THEN. SHOULD BE A
NORTHEAST TO SOUTHWEST TEMP GRADIENT WITH THE NORTHWEST FLOW UNTIL
SUNDAY WHEN TEMPS RISE AHEAD OF THE NEXT WAVE AND FRONT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 647 PM CDT MON JUL 15 2013
AS DEEPER MOISTURE FEED IS CUTOFF A BIT AND RAIN SHOWERS DIMINISH
IN BAND FROM SE ND INTO BEMIDJI AREA...HAVE SEEN PERSISTENT MVFR
CIGS GRADUALLY RISE INTO VFR RANGE. SOME POCKET OF MVFR CIGS IN
DVL BASIN BUT THAT AREA TOO WILL SEE THAT SCATTER OUT LEAVING A
MOSTLY HIGH BASED CU/AC/CI LAYER TONIGHT. I THINK DECENT RISK OF A
STORM MAKING IT TO DVL REGION 06Z-07Z.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...RIDDLE
SHORT TERM...JR
LONG TERM...JR/GODON
AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
306 PM CDT SUN JUL 14 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 306 PM CDT SUN JUL 14 2013
VERY INTERESTING SYNOPTIC PATTERN WITH WELL ADVERTISED
RETROGRESSION OF UPPER LOW ACROSS MIDWEST. AS THIS SYSTEM MOVES
WEST-SOUTHWEST A SHORT WAVE OVER BRITISH COLUMBIA WILL MOVE EAST-
NORTHEAST. ANOTHER SHORTWAVE OVER NORTH CENTRAL MONTANA IS
GENERATING TSRA OVER EASTERN MONTANA AND WESTERN ND. THE LOW TO OUR
SOUTH HAS HELPED PRODUCE MULTIPLE FEEDS OF DEEP LAYERED MOISTURE
INTO THE CONVERGENT ZONE ALONG A BDE...BJI TO BWP LINE. THIS HAS
KEPT CONVECTION GOING ACROSS PARTS OF THE CWFA TODAY.
TONIGHT...DRIER SURFACE AIR AND UPPER CONVERGENCE IS HELPING TO
STABILIZE THE LOWER LAYERS AND SHRINK THE AREA OF CONVECTION. HAVE
FOLLOWED THE THE HRRR IN THE OVERNIGHT WHICH DECREASES POPS OVER
THE SOUTH WHILE INCREASING THEM IN THE DEVILS LAKE BASIN AFTER
06Z. EXPECT ONLY ISOLD TO WDLY SCATTERED SHRA/TSRA TONIGHT.
MONDAY...BOUNDARY BEGINS TO LIFT NORTH DURING THE MORNING. THERE
COULD BE LINGERING LIFT FROM THE MONTANA WAVE TO INTERACT WITH THE
NORTHWARD MOVING BOUNDARY TO MAINTAIN / REGENERATE TSRA MONDAY.
INSTABILITY AND LIFT MARGINAL AS FRONT MOVES NORTH...850 JET
FORECAST 20 TO 25 KTS...SHOWALTERS -2 TO -4 AND MU-CAPES AROUND
1500 J/KG SUGGEST LOW RISK SEVERE.
MONDAY NIGHT...BOUNDARY LIFTS NORTH TOWARDS INTERNATIONAL BORDER.
DRIER AIR MOVING IN FROM THE SOUTH...COURTESY OF LOWER PLAINS
CIRCULATION... REDUCES THE CONVECTIVE RISK. HAVE CONFINED POPS
NORTH OF THE U.S. 2 CORRIDOR AFTER 00Z MONDAY.
TUESDAY...BOUNDARY FORECAST TO CLEAR THE CWFA FOR THE MORNING
TUESDAY. ATMOSPHERE REMAINS RELATIVELY STABLE UNTIL LATER IN THE
DAY SO HAVE KEPT THE FORENOON PERIOD PRECIPITATION FREE. SHORTWAVE
MOVING FROM ALBERTA TO NORTHERN MANITOBA BUILDS A WEAK SURFACE
HIGH PUSHING THE FRONT BACK SOUTH. AS BOUNDARY BEGINS TO DROP
ACROSS THE AREA...DAYTIME HEATING AND MARGINAL MOISTURE SHOULD
RESULT IN TSRA LATER TUESDAY AFTERNOON AND EVENING.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 306 PM CDT SUN JUL 14 2013
TUESDAY NIGHT AND WEDNESDAY SHOULD SEE A FRONTAL BOUNDARY MOVING
INTO THE NORTHERN CWA AND STALLING OUT AS A LARGE UPPER RIDGE
CONTINUES OVER MUCH OF THE CENTRAL CONUS AND TROUGHING SETTING UP
OVER CANADA. THE FRONT MAY START TO WASH OUT A BIT DURING THE DAY
ON WEDNESDAY...BUT THINK THERE WILL BE ENOUGH CONVERGENCE REMAINING
ALONG IT TO ALLOW THUNDERSTORMS TO CONTINUE TO DEVELOP. CONTINUED TO
KEEP 20-40 POPS TUESDAY NIGHT AND WEDNESDAY NEAR THE CANADIAN BORDER
WHERE THE FRONT SEEMS LIKELY TO SET UP.
THURSDAY...AN UPPER SHORTWAVE WILL BEGIN TO DIG INTO
SASKATCHEWAN...AND THE BOUNDARY SHOULD MOVE SOUTH. THINK WITH THE
FRONT COMING THROUGH AND DECREASING 500MB HEIGHTS THERE WILL BE A
GOOD CHANCE FOR PRECIPITATION SO KEPT PRETTY HIGH POPS GOING. THE
SHORTWAVE WILL DIG DOWN INTO THE CWA ON FRIDAY...WITH PRECIP
STARTING TO TAPER OFF AND TEMPERATURES DROPPING BACK TO NEAR
SEASONAL NORMALS.
FOR NEXT WEEKEND...THE MODELS ARE IN PRETTY GOOD AGREEMENT ON
NORTHWESTERLY FLOW ALOFT SETTING UP...ALTHOUGH DIFFER QUITE A BIT ON
THE TIMING OF VARIOUS WEAK SHORTWAVES COMING THROUGH. THUS...SEE
LITTLE REASON TO DEVIATE MUCH FROM ALLBLEND POPS. TEMPS SHOULD BE
CLOSE TO AVERAGE FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 306 PM CDT SUN JUL 14 2013
FRONTAL BOUNDARY CONTINUES TO WOBBLE AROUND BUT NOT MOVE
MUCH...CONTINUING FROM JUST SOUTHWEST OF KFAR TO AROUND KBDE. THINK
THERE SHOULD BE SOME LIFTING NORTHWARD OF THE FRONT LATER THIS
AFTERNOON AND INTO TONIGHT...WITH KFAR AND KBJI SHOWING SOME
SCATTERED SHRA AND TS...ALONG WITH MVFR CEILINGS AT TIMES UNDER
DEEPER MOISTURE. NORTH OF THE FRONT...KDVL...KGFK AND KTVF HAVE ALL
GONE TO VFR CIGS...AND THIS TREND SHOULD CONTINUE THROUGH THE REST
OF THE TAF PERIOD. REMOVED PRECIP MENTION AS THINK THAT ANY
ACTIVITY WILL BE IN THE GENERAL VICINITY OF THE FRONT AND THAT
SHOULD BE WELL SOUTH OF THOSE TAF SITES.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...EWENS
LONG TERM...JR
AVIATION...JR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1252 PM CDT SUN JUL 14 2013
.UPDATE...
ISSUED AT 1252 PM CDT SUN JUL 14 2013
THIS EARLY AFTERNOON UPDATE REVOLVES AROUND THE SLOW MOVING
CONVECTIVE AREA OVER THE SOUTHEAST PORTION OF THE CWFA. WE ISSUED
AN FLS FOR THE 1.5 TO 2.5 INCHES OF RAIN IN GRANT AND OTTER-TAIL
COUNTIES. 88D ESTIMATES SUGGEST ISOLATED 3 TO 4 INCH AMOUNTS...
YET REGION IS DRY ENOUGH AND RATES SLOW ENOUGH THAT FLASH FLOODING
NOT LIKELY. THE 88D ESTIMATES SUGGEST RAINFALL RATES OF UP TO 0.50
INCH/HOUR MOVING THROUGH THE FLS AREA. HRRR SUGGESTS AN ADDITIONAL
1 TO 2 INCHES ARE POSSIBLE IN THAT AREA OVER THE NEXT 15 HOURS.
WILL MONITOR FOR POSSIBLE UPGRADE IF STRONGER CONVECTION DEVELOPS.
PWATS ARE EXTREMELY HIGH FOR OUR AREA...GTR 2 INCHES...DECREASING
FORCING WITH DRIER AIR INTRUDING FROM THE NORTH AND CONFLUENT FLOW
ALOFT SHOULD HOLD WIDESPREAD EXCESSIVE AMOUNTS DOWN.
UPDATE ISSUED AT 923 AM CDT SUN JUL 14 2013
UPDATED THROUGH THE AFTERNOON TO ADJUST FOR QUASI-STATIONARY BAND
OF CONVECTION. LEANED ON THE HRRR THROUGH 18Z AND SREF THROUGH 00Z
TO BLEND. HAVE UPPED THE QPF TO ACCOUNT FOR THE OBSERVED HEAVIER
RAINS IN PROGRESS. A PWS IN HOFFMAN/GRANT COUNTY/SHOWS 1.8 INCHES
MIDNIGHT THROUGH 9AM. BIAS FFMP/LEGACY AND DUAL POL QPE A TAD HOT
BUT HAVE GENERAL IDEA. WILL BLEND TEMPS DOWN IN CLOUDS AND RAIN
AREAS AS WELL.
UPDATE ISSUED AT 640 AM CDT SUN JUL 14 2013
HAVE CANCELED SVR TSTM WATCH FOR FAR SERN ND COUNTIES. INCREASING
CONVECTION OVER SERN SD AND DECREASING LLJET HAVE LIMITED THE LOW
LEVEL MOISTURE CONVERGENCE INTO NERN SD AND OUR SOUTHERN FA. SFC
BOUNDARY REMAINS STALLED ACROSS SERN ND INTO NWRN MN... ROUGHLY
ALG AN ABR-FAR-BDE LINE. SOUTH OF THIS BOUNDARY...DEEP CONVECTION
HAS INCREASED FROM ERN SD INTO CNTRL MN. THIS AREA SHUD REMAIN
ACTIVE THROUGHOUT THE MORNING.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 355 AM CDT SUN JUL 14 2013
A SURFACE BOUNDARY IS DRAPED ACROSS THE FA AND EXTENDS FROM A LOW
PRESSURE CENTER IN WRN NE... THROUGH ECNTRL ND INTO NORTHWEST ONT.
DEWPTS FROM THE UPPER 60S TO LOWER 70S CONTINUE TO PILE UP AHEAD
OF THE BOUNDARY... AND WITH A WEAK 850 LLJET EXTENDING UP FROM ERN
SD... SHUD MAINTAIN AN AREA OF +1000 MUCAPE INTO SERN ND AND
PORTIONS OF WCNTRL MN THROUGH THE MORNING.
A CONVECTIVE COMPLEX NOW PUSHING FM NCNTRL SD INTO NERN SD IS
EXPECTED TO DRIVE INTO THIS UNSTABLE AIRMASS AND PERHAPS PENETRATE
TO THE MN BORDER WITH STRONG TO SEVERE WIND POTENTIAL. THE COMPLEX
IS MOVING AWAY FROM ITS AREA OF BEST DEEP LAYER SHEER AND BUMPING
UP AGAINST A SOMEWHAT WARMER MID LEVEL WARM POCKET... SO LONGEVITY
IS IN QUESTION. EXPECT THIS EARLY CONVECTIVE COMPLEX TO WEAKEN
AND DISSIPATE THROUGH MID MORNING.
THAT ALL SAID... H7 TEMPS ARE EXPECTED TO COOL A BIT FURTHER INTO
THIS AFTERNOON OVER SERN ND AND NWRN MN WHILE LOW LEVEL MOISTURE
TRANSPORT KICKS UP A BIT. WITH THIS...AREAS ALONG AND AHEAD OF
THE SURFACE BOUNDARY SHUD DESTABILIZE SIGNIFICANTLY THROUGH EARLY
AFTERNOON AND DEEP CONVECTION INCREASE... FIRST ACROSS THE
SOUTHERN FA AND THEN EXPANDING A BIT NORTHWARD FROM LATE AFTERNOON
INTO THE EVENING.
THIS NOW QUASI STATIONARY BOUNDARY SHUD REMAIN A FOCUS FOR
CONVECTION INTO MONDAY MORNING... SHIFTING SLOWLY NORTHWARD AND
WEAKENING THROUGHOUT THE DAY.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 355 AM CDT CDT SUN JUL 14 2013
MONDAY NIGHT AND TUESDAY...SOUTHWESTERLY FLOW ALOFT CONTINUES WITH
ANOTHER SHORTWAVE MOVING THROUGH SOUTHERN CANADA. A SFC TROUGH
DEVELOPING OVER THE NORTHERN ROCKIES ON MONDAY WILL HELP PUSH WARM
MOIST AIR BACK INTO THE CWA. HOWEVER...700MB TEMPS WILL ALSO BE ON
THE RISE SO WILL KEEP POPS IN THE 20 TO 30 PERCENT RANGE AS
CAPPING SHOULD MINIMIZE COVERAGE. THE UPPER SHORTWAVE OVER CANADA
MOVES BY TUESDAY AND SHOULD HELP PUSH ANOTHER WEAK FRONTAL
BOUNDARY INTO THE NORTHERN CWA.
TUESDAY NIGHT THROUGH SATURDAY...LONG WAVE UPPER LEVEL RIDGE
EXTENDS FROM THE OH VALLEY TO THE DESERT SOUTHWEST. BETWEEN DAY 5
AND DAY 7 EAST END OF UPPER RIDGE BEGINS TO SHIFT WEST AND SOUTH
AS UPPER TROUGH ROTATES INTO EASTERN CANADA AND THE NEW ENGLAND
STATES. GFS AND ECMWF WERE IN REASONABLE AGREEMENT AT THE
BEGINNING OF THE PERIOD. THE GFS BECOMES FASTER BY THE END OF THE
PERIOD. WILL USE A BLEND OF THE ECMWF AND GFS THIS PERIOD.
WILL TRIM BACK POPS ON THU NIGHT IN NORTHWEST ZONES AND TAKE OUT
PRECIP ON FRI.
TEMPS INCREASED A DEGREE OR TWO FOR WED...FRI AND SAT AND DECREASE A
DEGREE FOR THU FROM YESTERDAYS RUN.
&&
.AVIATION...
FRONTAL BOUNDARY CONTINUES TO WOBBLE AROUND BUT NOT MOVE
MUCH...CONTINUING FROM JUST SOUTHWEST OF KFAR TO AROUND KBDE. THINK
THERE SHOULD BE SOME LIFTING NORTHWARD OF THE FRONT LATER THIS
AFTERNOON AND INTO TONIGHT...WITH KFAR AND KBJI SHOWING SOME
SCATTERED SHRA AND TS...ALONG WITH MVFR CEILINGS AT TIMES UNDER
DEEPER MOISTURE. NORTH OF THE FRONT...KDVL...KGFK AND KTVF HAVE ALL
GONE TO VFR CIGS...AND THIS TREND SHOULD CONTINUE THROUGH THE REST
OF THE TAF PERIOD. REMOVED PRECIP MENTION AS THINK THAT ANY
ACTIVITY WILL BE IN THE GENERAL VICINITY OF THE FRONT AND THAT
SHOULD BE WELL SOUTH OF THOSE TAF SITES.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...EWENS
SHORT TERM...EWENS
LONG TERM...HOPPES
AVIATION...JR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
924 AM CDT SUN JUL 14 2013
.UPDATE...
ISSUED AT 923 AM CDT SUN JUL 14 2013
UPDATED THROUGH THE AFTERNOON TO ADJUST FOR QUASI-STATIONARY BAND
OF CONVECTION. LEANED ON THE HRRR THROUGH 18Z AND SREF THROUGH 00Z
TO BLEND. HAVE UPPED THE QPF TO ACCOUNT FOR THE OBSERVED HEAVIER
RAINS IN PROGRESS. A PWS IN HOFFMAN/GRANT COUNTY/SHOWS 1.8 INCHES
MIDNIGHT THROUGH 9AM. BIAS FFMP/LEGACY AND DUAL POL QPE A TAD HOT
BUT HAVE GENERAL IDEA. WILL BLEND TEMPS DOWN IN CLOUDS AND RAIN
AREAS AS WELL.
UPDATE ISSUED AT 640 AM CDT SUN JUL 14 2013
HAVE CANCELED SVR TSTM WATCH FOR FAR SERN ND COUNTIES. INCREASING
CONVECTION OVER SERN SD AND DECREASING LLJET HAVE LIMITED THE LOW
LEVEL MOISTURE CONVERGENCE INTO NERN SD AND OUR SOUTHERN FA. SFC
BOUNDARY REMAINS STALLED ACROSS SERN ND INTO NWRN MN... ROUGHLY
ALG AN ABR-FAR-BDE LINE. SOUTH OF THIS BOUNDARY...DEEP CONVECTION
HAS INCREASED FROM ERN SD INTO CNTRL MN. THIS AREA SHUD REMAIN
ACTIVE THROUGHOUT THE MORNING.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 355 AM CDT SUN JUL 14 2013
A SURFACE BOUNDARY IS DRAPED ACROSS THE FA AND EXTENDS FROM A LOW
PRESSURE CENTER IN WRN NE... THROUGH ECNTRL ND INTO NORTHWEST ONT.
DEWPTS FROM THE UPPER 60S TO LOWER 70S CONTINUE TO PILE UP AHEAD
OF THE BOUNDARY... AND WITH A WEAK 850 LLJET EXTENDING UP FROM ERN
SD... SHUD MAINTAIN AN AREA OF +1000 MUCAPE INTO SERN ND AND
PORTIONS OF WCNTRL MN THROUGH THE MORNING.
A CONVECTIVE COMPLEX NOW PUSHING FM NCNTRL SD INTO NERN SD IS
EXPECTED TO DRIVE INTO THIS UNSTABLE AIRMASS AND PERHAPS PENETRATE
TO THE MN BORDER WITH STRONG TO SEVERE WIND POTENTIAL. THE COMPLEX
IS MOVING AWAY FROM ITS AREA OF BEST DEEP LAYER SHEER AND BUMPING
UP AGAINST A SOMEWHAT WARMER MID LEVEL WARM POCKET... SO LONGEVITY
IS IN QUESTION. EXPECT THIS EARLY CONVECTIVE COMPLEX TO WEAKEN
AND DISSIPATE THROUGH MID MORNING.
THAT ALL SAID... H7 TEMPS ARE EXPECTED TO COOL A BIT FURTHER INTO
THIS AFTERNOON OVER SERN ND AND NWRN MN WHILE LOW LEVEL MOISTURE
TRANSPORT KICKS UP A BIT. WITH THIS...AREAS ALONG AND AHEAD OF
THE SURFACE BOUNDARY SHUD DESTABILIZE SIGNIFICANTLY THROUGH EARLY
AFTERNOON AND DEEP CONVECTION INCREASE... FIRST ACROSS THE
SOUTHERN FA AND THEN EXPANDING A BIT NORTHWARD FROM LATE AFTERNOON
INTO THE EVENING.
THIS NOW QUASI STATIONARY BOUNDARY SHUD REMAIN A FOCUS FOR
CONVECTION INTO MONDAY MORNING... SHIFTING SLOWLY NORTHWARD AND
WEAKENING THROUGHOUT THE DAY.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 355 AM CDT CDT SUN JUL 14 2013
MONDAY NIGHT AND TUESDAY...SOUTHWESTERLY FLOW ALOFT CONTINUES WITH
ANOTHER SHORTWAVE MOVING THROUGH SOUTHERN CANADA. A SFC TROUGH
DEVELOPING OVER THE NORTHERN ROCKIES ON MONDAY WILL HELP PUSH WARM
MOIST AIR BACK INTO THE CWA. HOWEVER...700MB TEMPS WILL ALSO BE ON
THE RISE SO WILL KEEP POPS IN THE 20 TO 30 PERCENT RANGE AS
CAPPING SHOULD MINIMIZE COVERAGE. THE UPPER SHORTWAVE OVER CANADA
MOVES BY TUESDAY AND SHOULD HELP PUSH ANOTHER WEAK FRONTAL
BOUNDARY INTO THE NORTHERN CWA.
TUESDAY NIGHT THROUGH SATURDAY...LONG WAVE UPPER LEVEL RIDGE
EXTENDS FROM THE OH VALLEY TO THE DESERT SOUTHWEST. BETWEEN DAY 5
AND DAY 7 EAST END OF UPPER RIDGE BEGINS TO SHIFT WEST AND SOUTH
AS UPPER TROUGH ROTATES INTO EASTERN CANADA AND THE NEW ENGLAND
STATES. GFS AND ECMWF WERE IN REASONABLE AGREEMENT AT THE
BEGINNING OF THE PERIOD. THE GFS BECOMES FASTER BY THE END OF THE
PERIOD. WILL USE A BLEND OF THE ECMWF AND GFS THIS PERIOD.
WILL TRIM BACK POPS ON THU NIGHT IN NORTHWEST ZONES AND TAKE OUT
PRECIP ON FRI.
TEMPS INCREASED A DEGREE OR TWO FOR WED...FRI AND SAT AND DECREASE A
DEGREE FOR THU FROM YESTERDAYS RUN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 640 AM CDT SUN JUL 14 2013
QUASI STATIONARY SFC BOUNDARY STRETCHES ALONG AN ABR-FAR-BDE LINE.
NORTH OF THIS LINE...EXPECT PATCHY MVFR CIGS AND INCREASING
NORTHERLY BLAYER FLOW THROUGH THE MORNING. ALONG AND SOUTH OF
THIS BOUNDARY...SCT SHOWERS AND AN ISOLATED TSTM THROUGH THE
MORNING. SHOWERS AND EMBEDDED TSTMS SHUD BECOME MORE WIDEPSPREAD
THROUGH THE AFTERNOON SOUTH OF THIS BOUNDARY AND BEGIN TO PUSH
SLOWLY NORTHWARD IN THE LATE AFTERNOON AND EVENING.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...EWENS
SHORT TERM...GUST
LONG TERM...HOPPES
AVIATION...GUST
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
748 PM EDT MON JUL 15 2013
.SYNOPSIS...
A SPRAWLING AREA OF HIGH PRESSURE WILL STAY IN POSITION OVER THE
REGION THROUGH FRIDAY...PROVIDING ABOVE-NORMAL TEMPERATURES. ON
FRIDAY NIGHT AND INTO SATURDAY...A COLD FRONT WILL MOVE SOUTH FROM
THE GREAT LAKES...PASSING THROUGH THE OHIO VALLEY. THIS WILL
PROVIDE A CHANCE OF SHOWERS AND STORMS. WITH HIGH PRESSURE
BUILDING IN BEHIND THE FRONT...SLIGHTLY COOLER AND DRIER
CONDITIONS ARE EXPECTED FOR SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
WITH HIGH PRESSURE PROVIDING GENERALLY TRANQUIL (THOUGH WARM)
CONDITIONS ACROSS THE CWA TODAY...THE ONLY SIGNIFICANT FORECAST
QUESTION FOR TONIGHT IS THE POSSIBILITY OF A POP-UP SHOWER OR
THUNDERSTORM. CONVECTION IS DEVELOPING FAIRLY READILY ALONG AND
NORTH OF THE MICHIGAN BORDER...AND A FEW LIGHT ECHOES HAVE BEEN
OBSERVED JUST A COUPLE COUNTIES NORTH OF THE ILN CWA IN OHIO. LAPS
DATA SUGGESTS A FAIRLY UNIFORM FIELD OF AROUND 1500-2000 J/KG
CAPE (SURFACE BASED) ACROSS THE CWA...WITH SLIGHTLY MORE FURTHER
NORTH. WIND FLOW IS VERY LIGHT AND THERE IS VERY LITTLE IF ANY
FORCING...AND THERE IS ALSO A BIT OF INHIBITION (AS ALSO SUGGESTED
WITH A SMALL CAP ON RAP SOUNDINGS). THE FORECAST WILL CARRY A 10
PERCENT CHANCE OF A SHOWER OR STORM CWA-WIDE (10-POPS DO NOT SHOW
UP IN THE TEXT PRODUCTS) WITH A SLIGHT CHANCE IN THE FAR
NORTH...CLOSER TO THE SLIGHTLY HIGHER INSTABILITY AND A REALLY
SLIGHT AMOUNT OF 850MB CONVERGENCE IN THE TURNING FLOW AROUND THE
CENTER OF THE HIGH.
MIN TEMPS ARE NOT FAR FROM PERSISTENCE FROM LAST NIGHT...PERHAPS A
DEGREE OR TWO WARMER AS THE AIR MASS GRADUALLY ADJUSTS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
THE CENTER OF THE LARGE STACKED HIGH PRESSURE AREA WILL PARK
ITSELF OVER THE ILN CWA ON TUESDAY...REMAINING IN PLACE BEFORE IT
IS FINALLY SUPPRESSED ON FRIDAY. THE HEIGHTS ASSOCIATED WITH THIS
HIGH ARE POSSIBLY HISTORIC...BUT THE HEAT (THOUGH WELL ABOVE
NORMAL) IS NOT. 850MB TEMP ANOMALIES PEAK OUT AT ABOUT ONE
STANDARD DEVIATION ABOVE NORMAL OVER THE NEXT FEW DAYS.
HOWEVER...500MB HEIGHT ANOMALIES ARE EXPECTED TO BE TWO TO TWO AND
A HALF STANDARD DEVIATIONS ABOVE NORMAL. DESPITE THE STRENGTH OF
THE HIGH...MOIST CONDITIONS ARE ONE FACTOR KEEPING THE HEAT
DOWN...AND PROVIDING CUMULUS DEVELOPMENT AND A SLIM CHANCE FOR A
SHOWER OR STORM ON JUST ABOUT EVERY DAY THIS WEEK.
LOOKING AT PRECIPITATION CHANCES...WEAK TO ALMOST NON-EXISTENT
FORCING WILL KEEP THE THREAT FOR ORGANIZED STORMS AWAY UNTIL THE
WEEKEND. INSTABILITY WILL DRIVE ANYTHING THAT DEVELOPS OVER THE
NEXT FEW DAYS...AS CAPE VALUES CLIMB TO AROUND 2000 J/KG
(POTENTIALLY AS HIGH AS 3000 J/KG) TUESDAY AND WEDNESDAY. THE SREF
FAVORS CONVECTIVE POTENTIAL TUESDAY FROM LOWER MICHIGAN SSE TOWARD
LAKE ERIE...AND PERHAPS AS FAR SOUTH AS CENTRAL OHIO. A 20-POP
WILL BE USED IN THE NORTHEAST HALF OF THE CWA. WEDNESDAY...AS THE
CENTER OF THE HIGH SLOWLY DRIFTS WEST...CONDITIONS WILL BE A
LITTLE MORE FAVORABLE CWA-WIDE (WITH UP TO A 30 PERCENT CHANCE IN
THE FAR EASTERN CWA). THE EXPECTATION ON EACH DAY IS TYPICAL FOR
THIS SORT OF PATTERN...WITH SPARSE COVERAGE...SLOW
MOTIONS...DOWNPOURS AND GUSTY WINDS.
AS OF NOW...IT LOOKS LIKE THE HEAT (THROUGH WEDNESDAY) WILL HOLD
OFF JUST SHY OF ADVISORY CRITERIA. WITH 925MB TEMPS IN THE 22C-24C
RANGE...AND 850MB TEMPS IN THE 18C-19C RANGE...SURFACE TEMPS OF
AROUND 90 TO THE LOWER 90S ARE SUPPORTED. DEWPOINTS IN THE LOWER
70S (APPROACHING MID-70S BY WEDNESDAY) ARE EXPECTED...WHICH SHOULD
ALLOW FOR HEAT INDICES IN THE MIDDLE TO UPPER 90S. A FEW LOCATIONS
WILL PROBABLY BRIEFLY MAKE IT TO AROUND 100 FOR A HEAT INDEX...BUT
THIS IS NOT EXPECTED TO BE WIDESPREAD. THE LACK OF WIND MAY MAKE
CONDITIONS RATHER UNCOMFORTABLE...BUT MIXING POTENTIAL MAY ONLY BE
TO AROUND 850MB (THERE DOES NOT SEEM TO BE MUCH SUPPORT IN THE
FORECAST SOUNDINGS FOR ANYTHING HIGHER THAN THAT). MIN TEMPS WERE
RAISED A DEGREE OR TWO FOR TUESDAY AND WEDNESDAY NIGHT.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
COMPUTER MODELS ARE IN GOOD AGREEMENT THROUGH SATURDAY NECESSITATING
FEW CHANGES TO THE GOING FORECAST.
VERTICALLY STACKED HIGH PRESSURE STRETCHING FROM THE CENTRAL PLAINS
TO THE CENTRAL APPALACHIANS WILL CONTINUE TO DOMINATE ON THURSDAY.
A TROUGH MOVING ACROSS HUDSON BAY WILL ACT TO BEGIN SUPPRESSING THE
RIDGE...HOWEVER LOW LEVEL THERMAL PROFILES WILL CONTINUE TO SUPPORT
HIGH TEMPERATURES IN THE LOWER 90S AREA-WIDE. DEW POINTS IN THE
LOWER 70S WILL BRING ANOTHER DAY WITH HEAT INDICES NEAR OR POSSIBLY
EXCEEDING 100F. A STRAY THUNDERSTORM WILL BE POSSIBLE IN THIS
AIRMASS...ALTHOUGH THE LACK OF FORCING AND AT LEAST SOME CAPPING IN
PLACE SUGGEST MODEL QPF OUTPUT IS PROBABLY OVERDONE.
ON FRIDAY...UPPER HEIGHTS WILL BEGIN FALLING AS A VIGOROUS TROUGH
BEGINS DIVING THROUGH CENTRAL CANADA. A LITTLE HIGHER COVERAGE OF
THUNDERSTORMS MAY RESULT...AND WE WILL HAVE TO WATCH OUR NORTHERN
COUNTIES TO SEE WHAT EVOLVES FROM WHAT COULD BE AN ACTIVE WEATHER
DAY OVER THE GREAT LAKES. HIGH TEMPERATURES WILL STILL REACH THE 90S
FOR MANY...ALTHOUGH THE HEAT INDEX MAY BE A FEW DEGREES LOWER.
A COLD FRONT WILL DROP SOUTHWARD INTO THE AREA ON SATURDAY...LEADING
TO A FAIRLY HIGH CHANCES OF PRECIPITATION. OBVIOUSLY THIS FAR OUT
THE CONVECTIVE EVOLUTION REMAINS IN QUESTION THOUGH. SPC HAS
HIGHLIGHTED AREAS TO OUR NORTH (DAY 5/FRIDAY) AND EAST (DAY
6/SATURDAY) FOR SEVERE WEATHER...AND THIS COINCIDES WITH HIGHER WIND
SHEAR VALUES. HOWEVER...IT IS CERTAINLY POSSIBLE THE COLD FRONT
COULD BRING STRONG TO SEVERE STORMS TO OUR AREA AS WELL ON SATURDAY.
CONFIDENCE IS LOW ENOUGH TO LEAVE OUT OF THE HWO FOR NOW.
TEMPERATURES ON SATURDAY WILL BE TRICKY DEPENDING ON PRECIPITATION
TIMING.
EVEN THOUGH UPPER LEVEL HEIGHT PATTERNS ARE FAIRLY CONSISTENT...
THERE HAS BEEN DISAGREEMENT BETWEEN MODELS AND MODEL RUNS ON HOW FAR
SOUTH THE LOW LEVEL COLD FRONT WILL MAKE IT LATE IN THE WEEKEND.
GIVEN THE FRONT IS SOMEWHAT PARALLEL TO THE UPPER FLOW...FELT IT WAS
PRUDENT TO LINGER SOME POPS IN THE SOUTH FOR SUNDAY. RIGHT
NOW...HIGH PRESSURE TO THE NORTH APPEARS STRONG ENOUGH TO PROVIDE
DRY WEATHER FOR MONDAY. AFTER THE FRONT PASSES...TEMPERATURES WILL
RETURN CLOSER TO SEASONAL NORMALS (HIGHS IN LOWER TO MID 80S...LOWS
IN MID 60S).
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
A FEW ISOLATED SHRA HAVE POPPED UP IN THE HEATING OF THE DAY IN
CENTRAL OHIO NR KOSU AND SOUTH OF KCVG. THESE SHOULD BEGIN TO
DISSIPATE AFT 00Z AND SHOULDNT AFFECT THE TAFS.
STACKED HIGH PRESSURE RIDGE WILL REMAIN OVER THE TAFS TONIGHT AND TOMORROW.
SKIES SHOULD GO CLEAR AGAIN TONIGHT. WITH LIGHT WINDS AND
DEWPOINTS AROUND 70...TAFS SHOULD EXPERIENCE SOME MVFR FOG. THE
EXCEPTION WILL BE KLUK...WHERE DUE TO RIVER VALLEY FOG...IFR
CONDITIONS ARE EXPECTED.
FOG SHOULD BURN OFF QUICKLY AFTER SUNRISE TOMORROW. FAIR WX CU
SHOULD DEVELOP AGAIN AS THE HEATING INCREASES. THERE MIGHT BE AN
OUTSIDE CHANCE OF CONVECTION POPPING LATE TOMORROW AFTN...BUT NO
CONFIDENCE AT ALL TO PUT IT IN THE TAFS.
OUTLOOK...THUNDERSTORMS POSSIBLE SATURDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...HATZOS
SHORT TERM...HATZOS
LONG TERM...SNYDER
AVIATION...SITES
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
758 AM EDT SUN JUL 14 2013
.SYNOPSIS...
A LARGE HIGH PRESSURE SYSTEM AT THE SURFACE AND ALOFT OVER
PENNSYLVANIA WILL TRACK SLOWLY WESTWARD INTO THE OHIO VALLEY THIS
WEEK. A COLD FRONT WILL LIKELY PUSH SOUTHWARD THRU THE REGION BY
NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WEAK INVERTED SFC TROF AND ASSOC PLUME OF ANOMALOUS PWATS LIFTING
NORTHWARD INTO CENTRAL PA EARLY THIS AM. RADAR LOOP AT 09Z SHOWS
JUST A FEW LIGHT SHOWERS/SPRINKLES ALONG THIS BOUNDARY WEST OF
HARRISBURG. RAP OUTPUT SHOWS THIS BAND OF HIGHER PWATS LIFTING TO
THE N TIER COUNTIES BY LATE AM. HOWEVER...GIVEN CURRENT RADAR
COVERAGE AND LACK OF LG SCALE FORCING...WILL NOT EXPLICITLY
MENTION PRECIP IN THE FCST THIS MORNING.
PLENTY OF LOW LVL MOISTURE AND A LINGERING LIGHT SE FLOW IS
PROMOTING INCREASING LOW CLOUDS/FOG EARLY THIS AM...AS EVIDENCED
BY 11-3.9U SATL LOOP. HOWEVER...AS SFC HIGH PRES SLIDES SOUTHWARD
OFF THE E COAST...FLOW ACROSS PA WILL SHIFT FROM SE TO SOUTH...BRINGING
BRIGHTER AND WARMER CONDS BY AFTN. ENS MEAN 925 TEMPS SUPPORT HIGH
TEMPS BTWN 85-90F.
LINGERING INVERTED SFC TROUGH AND ASSOC BAND OF ANOMALOUS PWATS
WILL LIE ALONG THE NY/PA BORDER THIS AFTN. DIURNAL HEATING OF THIS
MOIST...UNSTABLE AIR MASS COULD PRODUCE ISOLATED AFTN TSRA ACROSS
THE N MTNS LATE IN THE DAY. WEAK SHEAR INDICATES ANY STORMS THAT
FORM WILL BE OF THE PULSE VARIETY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
ANY ISOLD...DIURNALLY-DRIVEN EVENING TSRA ACROSS THE NORTH SHOULD DIE
OUT ARND SUNSET. WARM AND MUGGY CONDS EXPECTED THE REST OF THE NIGHT
WITH TEMPS RANGING FROM THE M60S OVR THE ALLEGHENIES...TO ARND 70F
IN THE SUSQ VALLEY.
DESPITE PRESENCE OF ANOMALOUS 5H HIGH PRES OVR PA...DIURNAL
HEATING OF MOIST AIR MASS SHOULD BE SUFFICIENT TO BREAK CAP AT
ARND 650MB...PRODUCING A FEW TSRA MONDAY AFTN. LINGERING SFC TROF AND
ASSOC BAND OF ANOMALOUS PWATS IS FCST TO LIE ACROSS CENTRAL
PA...RESULTING IN THE SCT PM CONVECTION ACROSS CENTRAL PA. GEFS
MEAN 8H TEMPS ARND 19C SHOULD TRANSLATE TO HIGH TEMPS FROM THE
U80S ACROSS THE ALLEGHENY PLATEAU...TO THE M90S IN THE SUSQ
VALLEY. THE COMBINATION OF HEAT AND HUMIDITY SHOULD PUSH HEAT
INDICES TO NR 100F ACROSS THE SUSQ VALLEY. WILL LET LATER SHIFTS
DECIDE WHETHER TO PULL THE TRIGGER ON A HEAT ADVISORY WITH BENEFIT
OF LATER GUIDANCE.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
HIGH CONFIDENCE HEAT WAVE FOR CENTRAL PA MUCH OF NEXT WEEK...AS
ALL MED RANGE GUIDANCE SHOWING ANOMALOUS MID LVL HIGH PRESSURE
CENTER PARKED OVR THE OHIO VALLEY/MIDWEST WITH ANOMALOUS 8H TEMPS
OF NR 20C ACROSS PA.
THE DEVELOPING..DEEP LAYER NWRLY FLOW WOULD ORDINARILY BE QUITE
FAVORABLE FOR CONVECTION /EVEN A FEW MCS TYPE SYSTEMS/ MOVING
QUICKLY SE FROM THE UPPER GLAKES REGION AND INTO OUR AREA.
HOWEVER...IT APPEARS THAT EVEN THOUGH WE HAVE TREMENDOUS LLVL
MOISTURE...HEAT /WITH TEMPS IN THE L-MID 90S THROUGHOUT THE
VALLEYS/...AND ASSOCIATED PERIODS OF HIGH ML CAPE OF 2000-3000
J/KG...A STRONG MID LEVEL CAP /WITH 700 MB TEMPS AVERAGING 10-11C/
WILL PREVENT MUCH MORE THAN ISOLATED AND GENERALLY OROGRAPHICALLY
INDUCED MID TO LATE AFTERNOON SHOWERS AND THUNDERSTORMS FOR TUESDAY
THROUGH THURSDAY. PRACTICALLY ALL OF THE /ISOLATED/ CONVECTION
WILL BE IN THE 19-00Z TIMEFRAME EACH AFTERNOON/EVENING.
WILL STILL HAVE TO KEEP A CLOSE EYE JUST TO OUR NORTH AND NE FOR
THE POSSIBILITY OF SOME WEAKNESSES IN THIS CAP FROM A FEW WEAK
SHORT WAVES THAT MAY DROP TO DROP SE FROM NEW YORK STATE AND NIP
AWAY AT THE WWD MOVING UPPER HIGH AND MID LEVEL CAP.
ENOUGH LLVL CONVERGENCE AND INCREASED LG SCALE...DEEP LAYER UVVEL
MAY DEVELOP FRIDAY AFTERNOON /ALONG THE NRN EDGE OF THE
AFOREMENTIONED MID LEVEL CAP/ TO DEVELOP ONE OR MORE CLUSTERS OF
STRONG TO POTENTIALLY SEVERE TSRA JUST AHEAD OF A SFC CFRONT THAT
WILL EXTEND FROM THE WRN GLAKES...TO NEAR THE NORTH SHORE OF LAKE
ONTARIO BY 00Z SATURDAY. NRN PARTS OF THE CWA STAND THE GREATEST
CHC AT SEEING A TSRA LATE FRIDAY.
ALTHOUGH THE CURRENT MDL 8H TEMPS DON/T SUPPORT RECORD HIGHS...PERHAPS
THE MOST IMPORTANT ASPECT TO THIS UPCOMING HEAT WAVE WILL BE IT/S
DURATION...LASTING MONDAY THRU AT LEAST FRIDAY. DAILY HEAT INDICES
SHOULD TOP OUR NR 100F EACH DAY ACROSS THE SUSQ VALLEY...ALONG
WITH NIGHTTIME LOWS IN THE L70S.
BY NEXT WEEKEND...GEFS AND EC ENSEMBLE OUTPUT INDICATE A SFC
CFRONT WILL SAG SOUTH /WITH UPPER HEIGHTS LOWERING ACROSS THE
GLAKES AND NE REGION...AS A SERIES OF FAST MOVING...AND QUITE
POTENT SHORTWAVES RIDE THROUGH THE RIGHT ENTRANCE REGION OF THE
LARGER SCALE 110 KT 300 MB JET /SITUATED FROM LAKE SUPERIOR TO SRN
QUEBEC/. THIS SETUP WILL AFFORD THE CHC FOR A FEW ROUND OF STRONG
TO POTENTIALLY SVR TSRA /AND ONE OR MORE MCS FEATURES/.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
A LARGE HIGH PRESSURE SYSTEM AT THE SURFACE AND ALOFT WILL BUILD
WESTWARD FROM THE ATLANTIC OCEAN AND PARK ITSELF OVER THE OHIO
VALLEY...BRINGING A PERIOD OF EXCELLENT FLYING CONDITIONS.
STRATOCU DECK MAINLY OVER EASTERN HALF ALREADY SHOWING SIGNS OF
BREAKING UP AT 12Z...AND THIS TREND SHOULD CONTINUE OVER THE NEXT
1-2 HOURS BRINGING A WIDESPREAD VFR DAY FOR ALL. THIS WILL BE THE
BEGINNING OF A SEVERAL DAY PERIOD WITH OVERALL EXCELLENT FLYING
CONDITIONS...WITH ONLY LOCALIZED LIGHT MORNING FOG AND SMALL
CHANCES FOR AN AFTERNOON TSTM EACH DAY. TODAY THAT LOW TSTM CHANCE
WILL BE ACROSS THE NORTHERN TIER IN VICINITY OF A WEAKENING TROUGH
JUST TO OUR NORTH AND IN THE LAURELS WITH DIFFERENTIAL
HEATING...BUT CHANCES TOO LOW TO MENTION IN KBFD-KJST TAFS.
OUTLOOK...
MON-THU...MAINLY VFR. DAILY LOCAL RESTRICTIONS POSS IN LIGHT
MORNING FOG AND ISO AFT TSTMS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...DEVOIR/FITZGERALD
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
543 AM EDT SUN JUL 14 2013
.SYNOPSIS...
A LARGE HIGH PRESSURE SYSTEM AT THE SURFACE AND ALOFT OVER
PENNSYLVANIA WILL TRACK SLOWLY WESTWARD INTO THE OHIO VALLEY THIS
WEEK. A COLD FRONT WILL LIKELY PUSH SOUTHWARD THRU THE REGION BY
NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WEAK INVERTED SFC TROF AND ASSOC PLUME OF ANOMALOUS PWATS LIFTING
NORTHWARD INTO CENTRAL PA EARLY THIS AM. RADAR LOOP AT 09Z SHOWS
JUST A FEW LIGHT SHOWERS/SPRINKLES ALONG THIS BOUNDARY WEST OF
HARRISBURG. RAP OUTPUT SHOWS THIS BAND OF HIGHER PWATS LIFTING TO
THE N TIER COUNTIES BY LATE AM. HOWEVER...GIVEN CURRENT RADAR
COVERAGE AND LACK OF LG SCALE FORCING...WILL NOT EXPLICITLY
MENTION PRECIP IN THE FCST THIS MORNING.
PLENTY OF LOW LVL MOISTURE AND A LINGERING LIGHT SE FLOW IS
PROMOTING INCREASING LOW CLOUDS/FOG EARLY THIS AM...AS EVIDENCED
BY 11-3.9U SATL LOOP. HOWEVER...AS SFC HIGH PRES SLIDES SOUTHWARD
OFF THE E COAST...FLOW ACROSS PA WILL SHIFT FROM SE TO SOUTH...BRINGING
BRIGHTER AND WARMER CONDS BY AFTN. ENS MEAN 925 TEMPS SUPPORT HIGH
TEMPS BTWN 85-90F.
LINGERING INVERTED SFC TROUGH AND ASSOC BAND OF ANOMALOUS PWATS
WILL LIE ALONG THE NY/PA BORDER THIS AFTN. DIURNAL HEATING OF THIS
MOIST...UNSTABLE AIR MASS COULD PRODUCE ISOLATED AFTN TSRA ACROSS
THE N MTNS LATE IN THE DAY. WEAK SHEAR INDICATES ANY STORMS THAT
FORM WILL BE OF THE PULSE VARIETY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
ANY ISOLD...DIURNALLY-DRIVEN EVENING TSRA ACROSS THE NORTH SHOULD DIE
OUT ARND SUNSET. WARM AND MUGGY CONDS EXPECTED THE REST OF THE NIGHT
WITH TEMPS RANGING FROM THE M60S OVR THE ALLEGHENIES...TO ARND 70F
IN THE SUSQ VALLEY.
DESPITE PRESENCE OF ANOMALOUS 5H HIGH PRES OVR PA...DIURNAL
HEATING OF MOIST AIR MASS SHOULD BE SUFFICIENT TO BREAK CAP AT
ARND 650MB...PRODUCING A FEW TSRA MONDAY AFTN. LINGERING SFC TROF AND
ASSOC BAND OF ANOMALOUS PWATS IS FCST TO LIE ACROSS CENTRAL
PA...RESULTING IN THE SCT PM CONVECTION ACROSS CENTRAL PA. GEFS
MEAN 8H TEMPS ARND 19C SHOULD TRANSLATE TO HIGH TEMPS FROM THE
U80S ACROSS THE ALLEGHENY PLATEAU...TO THE M90S IN THE SUSQ
VALLEY. THE COMBINATION OF HEAT AND HUMIDITY SHOULD PUSH HEAT
INDICES TO NR 100F ACROSS THE SUSQ VALLEY. WILL LET LATER SHIFTS
DECIDE WHETHER TO PULL THE TRIGGER ON A HEAT ADVISORY WITH BENEFIT
OF LATER GUIDANCE.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
HIGH CONFIDENCE HEAT WAVE FOR CENTRAL PA MUCH OF NEXT WEEK...AS
ALL MED RANGE GUIDANCE SHOWING ANOMALOUS MID LVL HIGH PRESSURE
CENTER PARKED OVR THE OHIO VALLEY/MIDWEST WITH ANOMALOUS 8H TEMPS
OF NR 20C ACROSS PA.
THE DEVELOPING..DEEP LAYER NWRLY FLOW WOULD ORDINARILY BE QUITE
FAVORABLE FOR CONVECTION /EVEN A FEW MCS TYPE SYSTEMS/ MOVING
QUICKLY SE FROM THE UPPER GLAKES REGION AND INTO OUR AREA.
HOWEVER...IT APPEARS THAT EVEN THOUGH WE HAVE TREMENDOUS LLVL
MOISTURE...HEAT /WITH TEMPS IN THE L-MID 90S THROUGHOUT THE
VALLEYS/...AND ASSOCIATED PERIODS OF HIGH ML CAPE OF 2000-3000
J/KG...A STRONG MID LEVEL CAP /WITH 700 MB TEMPS AVERAGING 10-11C/
WILL PREVENT MUCH MORE THAN ISOLATED AND GENERALLY OROGRAPHICALLY
INDUCED MID TO LATE AFTERNOON SHOWERS AND THUNDERSTORMS FOR TUESDAY
THROUGH THURSDAY. PRACTICALLY ALL OF THE /ISOLATED/ CONVECTION
WILL BE IN THE 19-00Z TIMEFRAME EACH AFTERNOON/EVENING.
WILL STILL HAVE TO KEEP A CLOSE EYE JUST TO OUR NORTH AND NE FOR
THE POSSIBILITY OF SOME WEAKNESSES IN THIS CAP FROM A FEW WEAK
SHORT WAVES THAT MAY DROP TO DROP SE FROM NEW YORK STATE AND NIP
AWAY AT THE WWD MOVING UPPER HIGH AND MID LEVEL CAP.
ENOUGH LLVL CONVERGENCE AND INCREASED LG SCALE...DEEP LAYER UVVEL
MAY DEVELOP FRIDAY AFTERNOON /ALONG THE NRN EDGE OF THE
AFOREMENTIONED MID LEVEL CAP/ TO DEVELOP ONE OR MORE CLUSTERS OF
STRONG TO POTENTIALLY SEVERE TSRA JUST AHEAD OF A SFC CFRONT THAT
WILL EXTEND FROM THE WRN GLAKES...TO NEAR THE NORTH SHORE OF LAKE
ONTARIO BY 00Z SATURDAY. NRN PARTS OF THE CWA STAND THE GREATEST
CHC AT SEEING A TSRA LATE FRIDAY.
ALTHOUGH THE CURRENT MDL 8H TEMPS DON/T SUPPORT RECORD HIGHS...PERHAPS
THE MOST IMPORTANT ASPECT TO THIS UPCOMING HEAT WAVE WILL BE IT/S
DURATION...LASTING MONDAY THRU AT LEAST FRIDAY. DAILY HEAT INDICES
SHOULD TOP OUR NR 100F EACH DAY ACROSS THE SUSQ VALLEY...ALONG
WITH NIGHTTIME LOWS IN THE L70S.
BY NEXT WEEKEND...GEFS AND EC ENSEMBLE OUTPUT INDICATE A SFC
CFRONT WILL SAG SOUTH /WITH UPPER HEIGHTS LOWERING ACROSS THE
GLAKES AND NE REGION...AS A SERIES OF FAST MOVING...AND QUITE
POTENT SHORTWAVES RIDE THROUGH THE RIGHT ENTRANCE REGION OF THE
LARGER SCALE 110 KT 300 MB JET /SITUATED FROM LAKE SUPERIOR TO SRN
QUEBEC/. THIS SETUP WILL AFFORD THE CHC FOR A FEW ROUND OF STRONG
TO POTENTIALLY SVR TSRA /AND ONE OR MORE MCS FEATURES/.
&&
.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
A LARGE HIGH PRESSURE SYSTEM AT THE SURFACE AND ALOFT WILL BUILD
WESTWARD FROM THE ATLANTIC OCEAN AND PARK ITSELF OVER THE OHIO
VALLEY...BRINGING A PERIOD OF EXCELLENT FLYING CONDITIONS.
HOWEVER...BEFORE THAT WE/LL SEE LIGHT FOG AND AN IFR/MVFR STRATOCU
DECK DEVELOP IN SOUTHERLY FLOW OVER CENTRAL PA OVERNIGHT /AFTER
08Z/ AS LOW LEVEL MOISTURE REMAINS TRAPPED UNDER BUILDING
SUBSIDENCE INVERSION. WEAK SHOWERS DRIFTING NORTHWARD FROM
MARYLAND WILL CONTINUE TO FALL APART AS THEY APPROACH THE MASON
DIXON LINE.
LOW CIGS SHOULD CONTINUE UNTIL 14-15Z...WHEN BOUNDARY LAYER SHOULD
MIX OUT AND BRING VFR CONDITIONS FOR THE REMAINER OF THE DAY. THIS
WILL BE THE BEGINNING OF A SEVERAL DAY PERIOD WITH OVERALL
EXCELLENT FLYING CONDITIONS...WITH ONLY LOCALIZED MORNING FOG AND
CHANCES FOR AN AFTERNOON TSTM EACH DAY. TODAY THAT TSTM CHANCE
WILL BE ACROSS THE NORTHERN TIER IN VICINITY OF A WEAKENING TROUGH
JUST TO OUR NORTH AND IN THE LAURELS...BUT CHANCES TOO LOW TO
MENTION IN KBFD-KJST TAFS.
OUTLOOK...
MON-THU...MAINLY VFR. DAILY LOCAL RESTRICTIONS POSS IN LIGHT
MORNING FOG AND ISO AFT TSTMS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...DEVOIR/FITZGERALD
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS AMARILLO TX
310 PM CDT SUN JUL 14 2013
.SHORT TERM...
COLD FRONT NOW THROUGH ALL OF THE PANHANDLES AS OF 3 PM CDT. IN ITS
WAKE...DECREASING TEMPERATURES AND SCATTERED SHOWERS ACROSS.
FOR TONIGHT...SHOULD SEE COVERAGE OF SHOWERS INCREASE A BIT AND HIGH
RESOLUTION MODELS LIKE THE HRRR AND TTU WRF CONTINUE TO SHOW THIS
TREND. WITH VERY LIMITED INSTABILITY...EXPECT THE ACTIVITY TO
PRIMARILY BE LIGHT RAIN SHOWERS...THOUGH AN ISOLATED THUNDERSTORM IS
POSSIBLE.
TOMORROW THROUGH TUESDAY...EXPECT A LULL IN THE PRECIP STARTING SOMETIME
EARLY TOMORROW MORNING AND CONTINUING THROUGH MID DAY AS THE REGION
WILL BE ON THE DRIER NW SIDE OF THE LOW. AS THE LOW CONTINUES TO
SLIDE EAST TOMORROW NIGHT...EXPECT PRECIP TO SPREAD FROM EAST TO WEST
ONCE AGAIN...AS BETTER LIFT IS EXPECTED ON THE EASTERN SIDE OF THE
UPPER LEVEL LOW. STILL SOME QUESTION AS TO HOW FAR NORTH MOISTURE
WILL ADVECT AND IF CONVECTION FURTHER DOWN STATE WILL ROB SOME OF THE
MOISTURE ADVECTION FOR THE PANHANDLES. STILL THINK THE BEST CHANCE
WILL BE TOMORROW NIGHT...WITH CHANCES DECREASING AFTER THAT.
.LONG TERM...
WEDNESDAY THROUGH THURSDAY...COULD STILL SEE SOME LINGERING
CONVECTION EVEN THOUGH THE LOW WILL BE PROPAGATING OVER NORTHERN
MEXICO BY THIS POINT...THE RESULTING MID AND UPPER LEVEL
SOUTHEASTERLY FLOW SHOULD RESULT IN A MOIST FETCH FROM THE GULF.
FRIDAY THROUGH SUNDAY...CONSIDERABLE UNCERTAINTY IN THE UPPER LEVEL
PATTERN THROUGH THIS PERIOD. GFS SHOWS VERY WEAK FLOW OVER THE REGION
THROUGH THIS PERIOD...WITH THE HIGH BUILDING OVER THE WESTERN U.S.
WHILE THE ECMWF SHOWS THE HIGH BUILDING OVER THE ROCKIES THEN SLIDING
SE TOWARDS THE PANHANDLES. EITHER WAY...IT SHOULD BE A DRIER
PATTERN...WITH THE POSSIBLE EXCEPTION OF SOME MOUNTAIN CONVECTION
SLIDING INTO THE NW CORNER ON SATURDAY UNDER VERY WEAK NW FLOW.
JOHNSON
&&
.FIRE WEATHER...
MUCH COOLER WEATHER...RAIN CHANCES...AND RELATIVE HUMIDITY VALUES
WELL ABOVE 20 PERCENT WILL PRECLUDE ANY ELEVATED OR CRITICAL FIRE
WEATHER CONDITIONS FOR THE NEXT SEVERAL DAYS.
JOHNSON
&&
.PRELIMINARY POINT TEMPS/POPS...
AMARILLO TX 58 72 57 75 62 / 60 30 50 40 20
BEAVER OK 60 77 59 85 64 / 30 20 20 20 10
BOISE CITY OK 59 74 56 78 58 / 70 20 20 30 10
BORGER TX 63 77 61 78 64 / 60 30 40 40 20
BOYS RANCH TX 62 76 61 76 63 / 70 20 40 40 20
CANYON TX 60 73 58 73 62 / 70 30 50 50 30
CLARENDON TX 59 73 60 77 64 / 60 40 60 40 30
DALHART TX 58 75 57 76 60 / 70 30 30 30 20
GUYMON OK 61 77 59 82 62 / 50 20 20 30 10
HEREFORD TX 60 74 58 72 61 / 70 30 50 50 30
LIPSCOMB TX 60 78 61 82 64 / 40 30 30 30 10
PAMPA TX 58 72 59 77 62 / 50 30 50 40 20
SHAMROCK TX 60 77 61 82 65 / 50 50 50 40 20
WELLINGTON TX 62 78 63 84 67 / 60 50 60 40 30
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
07/16
AREA FORECAST DISCUSSION
NWS AMARILLO TX
1211 PM CDT SUN JUL 14 2013
.AVIATION...
PLEASE SEE DISCUSSION JUST ISSUED BELOW FOR MESOSCALE AND SYNOPITC
SITUATION. AS FOR AVIATION CONCERNS...SCT SHWRS WILL BE ONGOING
THROUGH THIS EVENING AND LIKELY PAST MIDNIGHT ESPECIALLY FOR KAMA.
MOIST UPSLOPE WILL BRING LOW CLOUDS AND MVFR CONDITIONS TO THE TAF
SITES LATER TONIGHT AND PERSIST UNTIL 18Z MONDAY.
&&
.PREV DISCUSSION... /ISSUED 1200 PM CDT SUN JUL 14 2013/
UPDATE...
THE FRONT IS NOW PUSHING INTO THE WESTERN PANHANDLES...HAVING JUST
PASSED AMARILLO AND GUYMON. FOR LOCATIONS EAST OF THE FRONT...THEY
HAVE ALREADY REACHED THE HIGH FOR THE DAY...AS THERE IS GENERALLY A
10 DEGREE OR MORE TEMPERATURE DROP WITH THE FRONT. THUS HAVE UPDATED
TEMPERATURES AND WIND TO REFLECT THIS EARLIER ARRIVAL OF THE FRONT.
ALSO...COVERAGE OF SHOWERS ACROSS THE PANHANDLES HAS INCREASED...AND
BOTH THE HRRR AND THE TTU WRF SHOW THE TREND CONTINUING AS THE FRONT
MOVES FURTHER WEST. THUS...HAVE STARTED MENTION OF PRECIPITATION
ACROSS THE AREA NOW...CONTINUING THROUGH THE REST OF THE AFTERNOON.
JOHNSON
PREV DISCUSSION... /ISSUED 652 AM CDT SUN JUL 14 2013/
AVIATION...
FOR THE 12Z TAFS, WE HAVE A COMPLICATED FORECAST.
HAVE MODERATE TO HIGH CONFIDENCE KAMA AND KDHT WILL HAVE VCTS 23Z-02Z
AND 20Z-01Z, RESPECTIVELY. KGUY COULD BE IMPACTED BY VCTS 20Z-00Z,
BUT CONFIDENCE OF OCCURRENCE IS TOO LOW TO MENTION. IF ANY TERMINAL
IS DIRECTLY IMPACTED BY -TSRA, BRIEF WIND GUSTS UP TO 40 KT AND IFR
CONDITIONS WILL BE POSSIBLE. ALTHOUGH AN ISOLATED -TSRA CAN`T BE
RULED OUT 02Z-08Z, THINK -SHRA WILL BE THE MOST PREVALENT TYPE OF
PRECIPITATION AT ALL TERMINALS.
GUSTY EASTERLY WINDS UP TO 30 KT WILL DEVELOP BEHIND A COLD FRONT
WITH THE STRONGEST WINDS OCCURRING 1930Z-00Z.
VERY HIGH CONFIDENCE THAT ALL TERMINALS WILL EXPERIENCE AT LEAST MVFR
CONDITIONS AFTER 02Z. HAVE MODERATE TO HIGH CONFIDENCE THAT KAMA
WILL SEE IFR (POSSIBLY LIFR) CONDITIONS AFTER 07Z. KDHT AND KGUY
COULD ALSO SEE IFR CONDITIONS AFTER 06Z, BUT CONFIDENCE OF OCCURRENCE
IS A LITTLE TOO LOW TO MENTION AT THIS TIME.
JACKSON
PREV DISCUSSION... /ISSUED 435 AM CDT SUN JUL 14 2013/
DISCUSSION...
BIG CHANGES ARE IN STORE FOR TODAY AND THE START OF THE WORK WEEK AS
AN UNSEASONABLY WESTWARD TRAVELING CLOSED UPPER LEVEL LOW SIGNIFICANTLY
IMPACTS THE WEATHER ACROSS THE REGION.
THE ARRIVAL OF A BACKDOOR COLD FRONT AND SUBSEQUENT CLOUD COVER AND
CONVECTION WILL PLAY A HUGE ROLE IN HIGH TEMPERATURES TODAY MAKING
QUITE A TRICKY FORECAST ESPECIALLY FOR LOCATIONS IN THE CENTRAL AND
EASTERN PANHANDLES. LATEST SHORT RANGE MODELS SUGGEST THAT THE CLOSED
UPPER LOW WILL ARRIVE SLIGHTLY LATER THAN PREVIOUSLY THOUGHT WITH THE
EASTERLY WIND SHIFT NOT OCCURRING IN AMARILLO UNTIL LATE AFTERNOON.
WITH THAT SAID...INCREASED HIGH TEMPERATURES AND DECREASED CHANCES
FOR RAIN ACROSS MUCH OF THE AREA WITH EXCEPTION OF THE FAR EASTERN
PORTIONS OF THE PANHANDLES.
FIRST ROUND OF SHOWERS AND THUNDERSTORMS WILL OCCUR TONIGHT AS THE
UPPER LOW TRACKS ACROSS THE AREA. HEAVIEST RAIN DOES APPEAR TO OCCUR
JUST SOUTH OF THE PANHANDLES...SO HIGHEST POPS WILL BE ALONG AND
SOUTH OF I-40 AS WELL AS THE FAR WESTERN PANHANDLES...AND THEN DECREASE
AS YOU GO NORTHEAST. SOMEWHAT OF A LULL LOOKS TO TAKE PLACE DURING
THE DAY ON MONDAY BEFORE ANOTHER IMPULSE WRAPS AROUND THE UPPER LOW
GIVING THE AREA ROUND TWO OF CONVECTION LATE MONDAY INTO MONDAY
NIGHT...AND LIKELY CONTINUING INTO EARLY TUESDAY. THIS TIME FRAME
LOOKS TO BE THE BEST CHANCES FOR THE HEAVIEST PRECIPITATION FOR THE
AREA BUT ONCE AGAIN THE HIGHEST POPS WILL BE ACROSS THE SOUTHERN HALF
OF THE FORECAST AREA.
AS FAR AS TEMPERATURES ON MONDAY AND TUESDAY...HIGHS STILL LOOK ON
TRACK TO ONLY REACH THE 70S ON BOTH DAYS WITH A FEW 80 DEGREE
READINGS POSSIBLE IN THE DRIER OKLAHOMA PANHANDLE. STILL QUITE
CONFIDENT THAT AMARILLO WILL SHATTER THE LOW MAXIMUM TEMPERATURE
RECORD ON MONDAY (79 IN 1898) WITH THE CURRENT FORECAST OF 74
DEGREES. LOW TEMPERATURES WILL BE UNSEASONABLY COOL AS WELL WITH LOWS
IN THE 50S.
AS THE UPPER LOW MOVES SOUTHWEST AWAY FROM THE REGION...ITS IMPACTS
WILL NOT BE QUITE AS PROMINENT OVER THE AREA. REGARDLESS...THINK
THERE WILL BE ENOUGH MOISTURE ALONG WITH A FEW UPPER LEVEL IMPULSES
AROUND TO CONTINUE DEVELOPING CONVECTION OVER THE AREA TUESDAY
NIGHT THROUGH POSSIBLY THURSDAY...BUT RAINFALL CHANCES REALLY LOOK
MUCH LOWER AND CONFINED TO THE TEXAS PANHANDLE...AND MOSTLY THE
SOUTHERN PORTIONS. HIGH TEMPERATURES WILL REBOUND BACK INTO THE 80S
WEDNESDAY AND THURSDAY WITH THE 90S RETURNING TO THE OKLAHOMA
PANHANDLE.
MOSTLY DRY WEATHER RETURNS FRIDAY AND THE WEEKEND WITH EXCEPTION OF
THE EXTREME NORTHWEST PORTIONS OF THE PANHANDLES AS SOME DIURNAL
CONVECTION COULD DEVELOP OFF OF THE HIGHER TERRAN OVER SOUTHEAST
COLORADO AND NORTHEAST NEW MEXICO. BEST RAIN CHANCES APPEAR TO BE
SATURDAY AND ESPECIALLY SUNDAY ALTHOUGH THINK MOST AREAS WILL REMAIN
DRY. TEMPERATURES RETURN BACK TO SEASONAL NORMALS WITH HIGHS IN THE
90S AND LOWS N THE 60S.
KNS
FIRE WEATHER...
NO ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED TODAY
THROUGH AT LEAST TUESDAY AS MINIMUM AFTERNOON RELATIVE HUMIDITIES
WILL BE ABOVE 20 PERCENT...AND THE 20 FOOT WIND SPEEDS WILL REMAIN AT
OR BELOW 20 MPH. HOWEVER...AN ABRUPT SHIFT TO EASTERLY WINDS OF 20 TO
30 MPH WITH HIGHER GUSTS IS EXPECTED THIS AFTERNOON AS A BACKDOOR COLD
FRONT MOVES WEST ACROSS THE AREA. CHANCES FOR THUNDERSTORMS WILL
INCREASE LATE THIS AFTERNOON AND CONTINUE THROUGH WEDNESDAY ALLOWING
WETTING RAINS TO LIMIT ELEVATED AND CRITICAL FIRE WEATHER CONDITIONS.
KNS
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
07/16
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
1200 PM CDT SUN JUL 14 2013
.UPDATE...
THE FRONT IS NOW PUSHING INTO THE WESTERN PANHANDLES...HAVING JUST
PASSED AMARILLO AND GUYMON. FOR LOCATIONS EAST OF THE FRONT...THEY
HAVE ALREADY REACHED THE HIGH FOR THE DAY...AS THERE IS GENERALLY A
10 DEGREE OR MORE TEMPERATURE DROP WITH THE FRONT. THUS HAVE UPDATED
TEMPERATURES AND WIND TO REFLECT THIS EARLIER ARRIVAL OF THE FRONT.
ALSO...COVERAGE OF SHOWERS ACROSS THE PANHANDLES HAS INCREASED...AND
BOTH THE HRRR AND THE TTU WRF SHOW THE TREND CONTINUING AS THE FRONT
MOVES FURTHER WEST. THUS...HAVE STARTED MENTION OF PRECIPITATION
ACROSS THE AREA NOW...CONTINUING THROUGH THE REST OF THE AFTERNOON.
JOHNSON
&&
.PREV DISCUSSION... /ISSUED 652 AM CDT SUN JUL 14 2013/
AVIATION...
FOR THE 12Z TAFS, WE HAVE A COMPLICATED FORECAST.
HAVE MODERATE TO HIGH CONFIDENCE KAMA AND KDHT WILL HAVE VCTS 23Z-02Z
AND 20Z-01Z, RESPECTIVELY. KGUY COULD BE IMPACTED BY VCTS 20Z-00Z,
BUT CONFIDENCE OF OCCURRENCE IS TOO LOW TO MENTION. IF ANY TERMINAL
IS DIRECTLY IMPACTED BY -TSRA, BRIEF WIND GUSTS UP TO 40 KT AND IFR
CONDITIONS WILL BE POSSIBLE. ALTHOUGH AN ISOLATED -TSRA CAN`T BE
RULED OUT 02Z-08Z, THINK -SHRA WILL BE THE MOST PREVALENT TYPE OF
PRECIPITATION AT ALL TERMINALS.
GUSTY EASTERLY WINDS UP TO 30 KT WILL DEVELOP BEHIND A COLD FRONT
WITH THE STRONGEST WINDS OCCURRING 1930Z-00Z.
VERY HIGH CONFIDENCE THAT ALL TERMINALS WILL EXPERIENCE AT LEAST MVFR
CONDITIONS AFTER 02Z. HAVE MODERATE TO HIGH CONFIDENCE THAT KAMA
WILL SEE IFR (POSSIBLY LIFR) CONDITIONS AFTER 07Z. KDHT AND KGUY
COULD ALSO SEE IFR CONDITIONS AFTER 06Z, BUT CONFIDENCE OF OCCURRENCE
IS A LITTLE TOO LOW TO MENTION AT THIS TIME.
JACKSON
PREV DISCUSSION... /ISSUED 435 AM CDT SUN JUL 14 2013/
DISCUSSION...
BIG CHANGES ARE IN STORE FOR TODAY AND THE START OF THE WORK WEEK AS
AN UNSEASONABLY WESTWARD TRAVELING CLOSED UPPER LEVEL LOW SIGNIFICANTLY
IMPACTS THE WEATHER ACROSS THE REGION.
THE ARRIVAL OF A BACKDOOR COLD FRONT AND SUBSEQUENT CLOUD COVER AND
CONVECTION WILL PLAY A HUGE ROLE IN HIGH TEMPERATURES TODAY MAKING
QUITE A TRICKY FORECAST ESPECIALLY FOR LOCATIONS IN THE CENTRAL AND
EASTERN PANHANDLES. LATEST SHORT RANGE MODELS SUGGEST THAT THE CLOSED
UPPER LOW WILL ARRIVE SLIGHTLY LATER THAN PREVIOUSLY THOUGHT WITH THE
EASTERLY WIND SHIFT NOT OCCURRING IN AMARILLO UNTIL LATE AFTERNOON.
WITH THAT SAID...INCREASED HIGH TEMPERATURES AND DECREASED CHANCES
FOR RAIN ACROSS MUCH OF THE AREA WITH EXCEPTION OF THE FAR EASTERN
PORTIONS OF THE PANHANDLES.
FIRST ROUND OF SHOWERS AND THUNDERSTORMS WILL OCCUR TONIGHT AS THE
UPPER LOW TRACKS ACROSS THE AREA. HEAVIEST RAIN DOES APPEAR TO OCCUR
JUST SOUTH OF THE PANHANDLES...SO HIGHEST POPS WILL BE ALONG AND
SOUTH OF I-40 AS WELL AS THE FAR WESTERN PANHANDLES...AND THEN DECREASE
AS YOU GO NORTHEAST. SOMEWHAT OF A LULL LOOKS TO TAKE PLACE DURING
THE DAY ON MONDAY BEFORE ANOTHER IMPULSE WRAPS AROUND THE UPPER LOW
GIVING THE AREA ROUND TWO OF CONVECTION LATE MONDAY INTO MONDAY
NIGHT...AND LIKELY CONTINUING INTO EARLY TUESDAY. THIS TIME FRAME
LOOKS TO BE THE BEST CHANCES FOR THE HEAVIEST PRECIPITATION FOR THE
AREA BUT ONCE AGAIN THE HIGHEST POPS WILL BE ACROSS THE SOUTHERN HALF
OF THE FORECAST AREA.
AS FAR AS TEMPERATURES ON MONDAY AND TUESDAY...HIGHS STILL LOOK ON
TRACK TO ONLY REACH THE 70S ON BOTH DAYS WITH A FEW 80 DEGREE
READINGS POSSIBLE IN THE DRIER OKLAHOMA PANHANDLE. STILL QUITE
CONFIDENT THAT AMARILLO WILL SHATTER THE LOW MAXIMUM TEMPERATURE
RECORD ON MONDAY (79 IN 1898) WITH THE CURRENT FORECAST OF 74
DEGREES. LOW TEMPERATURES WILL BE UNSEASONABLY COOL AS WELL WITH LOWS
IN THE 50S.
AS THE UPPER LOW MOVES SOUTHWEST AWAY FROM THE REGION...ITS IMPACTS
WILL NOT BE QUITE AS PROMINENT OVER THE AREA. REGARDLESS...THINK
THERE WILL BE ENOUGH MOISTURE ALONG WITH A FEW UPPER LEVEL IMPULSES
AROUND TO CONTINUE DEVELOPING CONVECTION OVER THE AREA TUESDAY
NIGHT THROUGH POSSIBLY THURSDAY...BUT RAINFALL CHANCES REALLY LOOK
MUCH LOWER AND CONFINED TO THE TEXAS PANHANDLE...AND MOSTLY THE
SOUTHERN PORTIONS. HIGH TEMPERATURES WILL REBOUND BACK INTO THE 80S
WEDNESDAY AND THURSDAY WITH THE 90S RETURNING TO THE OKLAHOMA
PANHANDLE.
MOSTLY DRY WEATHER RETURNS FRIDAY AND THE WEEKEND WITH EXCEPTION OF
THE EXTREME NORTHWEST PORTIONS OF THE PANHANDLES AS SOME DIURNAL
CONVECTION COULD DEVELOP OFF OF THE HIGHER TERRAN OVER SOUTHEAST
COLORADO AND NORTHEAST NEW MEXICO. BEST RAIN CHANCES APPEAR TO BE
SATURDAY AND ESPECIALLY SUNDAY ALTHOUGH THINK MOST AREAS WILL REMAIN
DRY. TEMPERATURES RETURN BACK TO SEASONAL NORMALS WITH HIGHS IN THE
90S AND LOWS N THE 60S.
KNS
FIRE WEATHER...
NO ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED TODAY
THROUGH AT LEAST TUESDAY AS MINIMUM AFTERNOON RELATIVE HUMIDITIES
WILL BE ABOVE 20 PERCENT...AND THE 20 FOOT WIND SPEEDS WILL REMAIN AT
OR BELOW 20 MPH. HOWEVER...AN ABRUPT SHIFT TO EASTERLY WINDS OF 20 TO
30 MPH WITH HIGHER GUSTS IS EXPECTED THIS AFTERNOON AS A BACKDOOR COLD
FRONT MOVES WEST ACROSS THE AREA. CHANCES FOR THUNDERSTORMS WILL
INCREASE LATE THIS AFTERNOON AND CONTINUE THROUGH WEDNESDAY ALLOWING
WETTING RAINS TO LIMIT ELEVATED AND CRITICAL FIRE WEATHER CONDITIONS.
KNS
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
07/16
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
636 PM CDT MON JUL 15 2013
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 249 PM CDT MON JUL 15 2013
CURRENTLY AS OF 19Z...
WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED TROUGHING OVER
SOUTHWEST CANADA...AN UPPER LOW OVER THE TEXAS PANHANDLE
RETROGRADING WESTWARD...AND A NEAR 600 DAM HIGH NEAR TOLEDO OHIO
ALSO RETROGRADING WESTWARD. STANDARD DEVIATIONS AGAIN WITH THIS HIGH
ARE RUNNING 2.5 ABOVE NORMAL. BETWEEN THE UPPER LOW AND SUBTROPICAL
HIGH...DEEP LAYER SOUTH TO SOUTHEAST WINDS ARE ADVECTING HIGHER
PRECIPITABLE WATER VALUES TOWARDS THE FORECAST AREA. 12Z DVN AND ILX
REPORTED VALUES OF 1.89 AND 2.04 INCHES RESPECTIVELY. HIGHER SURFACE
DEWPOINTS IN THE LOW 70S HAVE ACCOMPANIED THIS DEEP MOISTURE. WITH
TEMPERATURES THAT HAVE CLIMBED INTO THE UPPER 80S/LOW 90S...
RESULTING IN MLCAPE VALUES OF 500-1000 J/KG...ISOLATED SHOWERS HAVE
FORMED. NO LIGHTNING YET...WHICH MAY BE A RESULT OF THE SHALLOW
NATURE OF THE SHOWERS AND DEEP WARM CLOUD DEPTHS PREVENTING ICE
PRODUCTION. DESPITE THE HIGH 500MB HEIGHTS OVER THE FORECAST
AREA...ON THE ORDER OF 594-597 DAM...850MB TEMPS ARE ONLY 16-17C.
THE REASON THESE ARE COOL COMPARED TO THE 500MB HEIGHT IS A RESULT
OF THE SUBTROPICAL HIGH BEING OF ATLANTIC OCEAN ORIGIN. HAD IT COME
OUT OF THE WESTERN U.S....THE 850MB TEMPS WOULD BE A LOT HIGHER.
SYNOPTIC OVERVIEW...
MODELS CONTINUE TO SHOW THE STRONG SUBTROPICAL HIGH DRIFTING
WESTWARD THROUGH TUESDAY...REACHING NEAR GARY INDIANA BY 00Z
WEDNESDAY. THUS...500MB HEIGHTS WILL CONTINUE TO RISE OVER THE
FORECAST AREA...IMPLYING INCREASING MID-LEVEL SUBSIDENCE.
FOR TONIGHT...
ANY AFTERNOON CONVECTION THAT IS SPREADING NORTHWARD...ACCOMPANYING
THE HIGHER PRECIPITABLE WATER...WILL DIMINISH BY 03Z THIS EVENING
WITH LOSS OF HEATING SINCE IT IS HIGHLY DIURNALLY DRIVEN. THE REST
OF THE NIGHT LOOKS DRY WITH ANY FORCING FOR NOCTURNAL CONVECTION
WELL NORTH OF THE FORECAST AREA.
ON TUESDAY...
THE BATTLE CONTINUES OF WHETHER OR NOT TO NEED A MENTION OF SHOWERS
AND THUNDERSTORMS IN THE AFTERNOON. MODELS WERE A LITTLE HYPERACTIVE
WITH DIURNAL CONVECTION TODAY...ESPECIALLY THE 15.12Z NAM SHOWING
PRECIP ACROSS ALL OF ILLINOIS BY 15Z AND THERE WAS NONE IN REALITY.
ALL MODELS ARE IN AGREEMENT OF MUCH LESS QPF...AND THE 15.12Z NAM
CONTINUES TO SHOW A DRY FORECAST FOR THE FORECAST AREA. THERE ARE
OTHER NEGATIVES TOO FOR CONVECTION...BEING CLOSER TO THE SUBTROPICAL
HIGH...AND 0.25-0.5 INCH DRYING OF PRECIPITABLE WATER VALUES
ORIGINATING FROM EASTERN KY/TN THIS MORNING. SEEING THE DRY FORECAST
FROM THE NAM...THE 15.12Z CANADIAN WHICH DID A GOOD JOB WITH PRECIP
TODAY AND IS DRY FOR TUESDAY...ALONG WITH OTHER MODELS SHOWING VERY
LITTLE IF ANY QPF...WENT BACK TO A DRY FORECAST. 850MB TEMPS ARE 2C
HIGHER TOMORROW...BETWEEN 18-19C...SO WE SHOULD SEE ABOUT A SIMILAR
INCREASE IN HIGH TEMPERATURES INTO UPPER 80S/LOW 90S. DEWPOINTS UP
IN THE UPPER 60S/LOW 70S AND THE FORECAST HIGH TEMPERATURES WILL
LIKELY LEAD TO PLENTY OF CUMULUS...BUT MORE IMPORTANTLY MAKE IT FEEL
MUGGY. HEAT INDICES ARE STILL FORECAST TO TOP OUT IN THE 95-100
RANGE.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 249 PM CDT MON JUL 15 2013
SYNOPTIC OVERVIEW...
MODELS REMAIN CONSISTENT IN THE STRONG SUBTROPICAL HIGH RETROGRADING
ACTUALLY SOUTHWESTWARD THROUGH THE REST OF THE WEEK. THIS IS IN
RESPONSE TO FIRST THE TROUGH IN SOUTHWEST CANADA MARCHING
EAST-NORTHEAST AND FLATTENING THE RIDGE...AND FINALLY AN UPPER LOW
CURRENTLY OFF THE COAST OF SAN FRANSISCO DROPPING SOUTHEAST THROUGH
THE FORECAST AREA AS A SHORTWAVE TROUGH. BY SATURDAY WE SHOULD BE
LOOKING AT TROUGHING OVER THE WESTERN GREAT LAKES VERSUS THE CURRENT
RIDGING. HEADING INTO SUNDAY AND MONDAY...INDICATIONS ARE THAT A
MORE POTENT SHORTWAVE TROUGH WILL BE APPROACHING THE AREA IN THE
NORTHWEST FLOW.
HAZARDS...
HEAT INDICES REMAIN THE BIG CONCERN. TUESDAY THROUGH THURSDAY LOOK
SOLID TO HAVE AFTERNOON HEAT INDICES BETWEEN 95-100...ESPECIALLY IN
THE VALLEYS. HEAT ADVISORY CRITERIA REQUIRES 100 OR GREATER FOR 1
DAY OR GREATER THAN 95 FOR 4 OR MORE DAYS. THE MORE LIKELY OF THE
TWO OPTIONS TO HIT WOULD BE DURATION. HEAT INDICES ONLY TOPPED OUT
IN THE UPPER 80S TO MID 90S TODAY...SO THAT MEANS FRIDAY WOULD NEED
95 OR GREATER. WITH CONCERN OF THE FRONT AND CONVECTION COMING
THROUGH FRIDAY...HAVE REFRAINED AT THIS TIME FROM ISSUING A HEAT
ADVISORY. HOWEVER...WE WILL ISSUE A SPECIAL WEATHER STATEMENT TO
DISCUSS THE HEAT. NOTE THAT THIS TIME PERIOD OF 15TH THROUGH 18TH
OF JULY IS COMMONLY THE TIME TO GET HEAT.
THERE IS A POSSIBILITY OF SEVERE WEATHER TOO IN THE THURSDAY THROUGH
FRIDAY TIME PERIOD. THURSDAY/THURSDAY NIGHT WOULD BE MORE TO THE
NORTH...PERHAPS JUST TAYLOR/CLARK COUNTIES AS ALSO SHOWN IN THE SPC
DAY 4-8 OUTLOOK. FRIDAY IT ALL DEPENDS ON THE FRONTAL TIMING.
ADDITIONALLY...THE BEST 0-6KM SHEAR IS BEHIND THE FRONT...WITH ONLY
30-35 KT ON THE FRONT. SO IT WOULD SEEM THAT OVERALL ANY SEVERE
WEATHER WOULD BE ISOLATED WITH DAMAGING WINDS AND HEAVY RAIN THE
MAIN HAZARDS.
DAILY DETAILS...
TUESDAY NIGHT AND WEDNESDAY...
A COLD FRONT ACCOMPANYING THE SOUTHWEST CANADA TROUGH IS PROGGED TO
DROP INTO NORTHERN MN BY 12Z WED AND THEN LAY UP BETWEEN ST CLOUD MN
AND UPPER MI LATE WEDNESDAY. ENVISIONING CONVECTION ON THIS
BOUNDARY...DUE TO PLENTIFUL MOISTURE AND INSTABILITY AROUND IT...
ALONG WITH LAKE BREEZE ENHANCED CONVERGENCE. GIVEN ITS LOCATION...
ANTICIPATING ANY CONVECTION TO STAY UP TO THE NORTH THROUGH
WEDNESDAY. WILL NEED TO MONITOR TAYLOR COUNTY FOR A NEED FOR SOME
CHANCES OF PRECIPITATION IN LATER FORECASTS SHOULD THE BOUNDARY DROP
FARTHER SOUTH. OTHERWISE...PRECIPITABLE WATER VALUES ARE PROGGED TO
HOLD STEADY OR EVEN FALL A LITTLE MORE COMPARED TO TUESDAY...SO NOT
ANTICIPATING ANY DIURNAL CONVECTION. WITH CONTINUED AIRMASS
MODIFICATION OF THE SUBTROPICAL HIGH...850MB TEMPS CLIMB ABOUT
ANOTHER 1C...WHICH WITH PLENTY OF SUN SHOULD YIELD ANOTHER DAY OF
HIGHS IN THE UPPER 80S/LOW 90S.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...
THIS PERIOD APPEARS A BIT MORE MUDDLED / LESS CONFIDENCE / THAN
BEFORE. WITH A ZONAL UPPER FLOW PATTERN THROUGH THURSDAY...THE COLD
FRONT SITUATED UP TO OUR NORTH APPEARS LIKELY TO STAY IN PLACE. IN
FACT...ON THURSDAY NIGHT WHEN THE SHORTWAVE TROUGH DROPS INTO THE
DAKOTAS...THE FRONT COULD EVEN GET PROPELLED NORTHWARD. 15.12Z
ECMWF/GFS/NAM/UKMET/CANADIAN ALL DEPICT THE NOSE/GRADIENT OF THE
850MB MOISTURE TRANSPORT STAYING FOCUSED FROM NORTHERN MN INTO
NORTHERN WI/UPPER MI AND LOWER MI FROM WEDNESDAY NIGHT THROUGH
THURSDAY NIGHT. FIGURE CONVECTION WOULD EITHER BE TIED TO THE FRONT
OR NOSE OF THE MOISTURE TRANSPORT...WHICH BOTH SUGGEST NORTH OF THE
FORECAST AREA. CORFIDI VECTORS ARE FAIRLY LIGHT TOO IN TERMS OF
SPEEDS WITH DIRECTIONS MAINLY WEST OR WEST-NORTHWEST...SO IF AN MCS
FORMS IT COULD END UP STAYING NORTH OF THE AREA AS WELL. GIVEN ALL
OF THIS...HAVE DECIDED TO SHIFT ALL OF THE PRECIPITATION CHANCES
NORTHWARD...WHICH MEANS A REDUCTION ACROSS THE BOARD. WOULD NOT BE
SURPRISED IF ALL STORMS DURING THIS PERIOD STAY NORTH OF HIGHWAY 29.
TEMPERATURES THURSDAY LOOK SIMILAR TO TUESDAY AND WEDNESDAY WITH
850MB TEMPS OF 18-20C.
FRIDAY THROUGH MONDAY...
GOOD AGREEMENT REMAINS ABOUT THE COLD FRONT COMING THROUGH THE AREA
ON FRIDAY...AHEAD OF THE SHORTWAVE TROUGH. HAVE SOME CONCERN THAT
THIS FRONT COULD COME THROUGH DRY SEEING THE 15.00Z ECMWF. THREE
NEGATIVES WITH THIS FRONT FOR CONVECTION IS THE POSITIVELY TITLED
NATURE OF THE SHORTWAVE...WEAK CONVERGENCE AND THAT THE TIMING MAY
BE MESSED UP. FOR NOW LEFT A MODEL CONSENSUS 20-40 PERCENT CHANCES
IN THE FORECAST INTO FRIDAY EVENING. HIGH PRESSURE IS STILL
INDICATED TO BUILD INTO THE AREA FOR THE WEEKEND. HOWEVER...BEING
UNDER UPPER TROUGHING YIELDS CONCERNS FOR SHORTWAVES COMING THROUGH
AT PEAK HEATING AND INITIATING CONVECTION. THE 15.00Z ECMWF HINTED
AT THIS FOR SATURDAY...BUT THE 15.12Z RUN IS NOW DRY. WITH A DRY GFS
FORECAST...HAVE KEPT SATURDAY INTO SATURDAY NIGHT DRY. MUCH OF
SUNDAY MAY BE DRY TOO...THOUGH THERE ARE INDICATIONS FROM THE 15.12Z
ECMWF OF A SHORTWAVE MOVING INTO MN BRINGING CONVECTION TO LOCATIONS
MAINLY WEST OF THE MS RIVER. THUS...HAD TO KEEP SOME LOW CHANCES
THERE. ADDITIONAL CHANCES IN THE 20-40 RANGE ARE FORECAST INTO
MONDAY ASSOCIATED WITH THE MORE POTENT SHORTWAVE. TIMING IS STILL
YET TO BE DETERMINED ON THIS SHORTWAVE.
&&
.AVIATION...TONIGHT AND TUESDAY
636 PM CDT MON JUL 15 2013
MOIST AND UNSTABLE AIRMASS OVER THE AREA THIS EVENING RESULTING IN
A MODERATE CUMULUS FIELD AND SOME ISOLATED SHOWERS. COULD BE SOME
LIGHTNING/THUNDER IN THERE AS WELL...BUT JUST NOT ENOUGH OF A
FOCUSING MECHANISM TO REALLY SUSTAIN A GOOD UPDRAFT. THIS ACTIVITY
IS DIURNALLY DRIVEN...SO WITH LOSS OF THE SUN SHOULD SEE A
DIMINISHING TREND. SOME OF THE MORE DEVELOPED SHOWERS MAY LINGER
THROUGH MIDNIGHT...PRIMARILY ACROSS SOUTHEAST MN/NORTHEAST IA.
OVERNIGHT...SOME RISK OF LIGHT FOG/MIST AGAIN TONIGHT AS WE SAW
THE PAST FEW NIGHTS. MODEL MOISTURE FIELDS AND SOUNDINGS HINT AT
THE POSSIBILITY. BUT NOTHING TOO RESTRICTIVE EXPECTED...5-6SM
APPEARS TO BE THE LOWEST VISIBILITY. EXPECT MORE CUMULUS AGAIN
TUESDAY...BUT SHOWERS LOOK LESS LIKELY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...MW
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
250 PM CDT SUN JUL 14 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 250 PM CDT SUN JUL 14 2013
MAIN FORECAST CONCERN IS ON THUNDERSTORM POTENTIAL FOR MONDAY.
CURRENTLY AS OF 19Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A SHARP SHORTWAVE TROUGH OVER BRITISH COLUMBIA...AN UPPER LOW
OVER EASTERN OKLAHOMA...A SHORTWAVE TROUGH STRETCHING FROM NORTHERN
MN INTO EASTERN SOUTH DAKOTA...AND THE BERMUDA HIGH OVER THE EASTERN
GREAT LAKES. 500MB HEIGHTS ASSOCIATED WITH THE BERMUDA HIGH ARE
QUITE IMPRESSIVE...NEARING 600 DAM OR 2.5 STANDARD DEVIATIONS ABOVE
NORMAL. DESPITE THE SUBSTANTIAL 500MB HEIGHTS...850MB TEMPS ARE ONLY
IN THE 15-18C UNDERNEATH IT PER 12Z RAOBS OR NEAR 1 STANDARD
DEVIATION ABOVE NORMAL. THE WESTERN EXTENT OF THE SUBTROPICAL RIDGE
HAS BEEN PROVIDING SUBSIDENCE OVER THE FORECAST AREA...RESULTING IN
DRY CONDITIONS WITH JUST SOME DIURNAL CUMULUS CLOUDS. TO OUR
WEST...A STREAM OF PRECIPITABLE WATER VALUES OF 1.65 TO 2 INCHES
PER GOES DERIVED IMAGERY STRETCHED FROM CENTRAL OKLAHOMA TO
EASTERN SOUTH DAKOTA AND NORTHERN MN. THIS STREAM OF HIGH MOISTURE
IS CO-LOCATED WITH THAT SHORTWAVE TROUGH IN THE NORTHERN PLAINS
AND DEFORMATION ON THE WEST SIDE OF THE UPPER LOW. NUMEROUS
SHOWERS AND THUNDERSTORMS WERE PRESENT IN THE STREAM.
EXPECT THE RETROGRADING 500MB PATTERN TO CONTINUE THROUGH THE SHORT
TERM PERIOD...SUCH THAT BY 00Z TUESDAY MODELS FORECAST THE BERMUDA
HIGH TO BE SITUATED NEAR THE OHIO/INDIANA BORDER. THIS RETROGRESSION
MEANS 500MB HEIGHTS ARE GOING TO RISE OVER THE FORECAST AREA...
IMPLYING SUBSIDENCE. NOT ANTICIPATING ANY PRECIPITATION TONIGHT
BEING IN THE NOCTURNAL COOLING PERIOD AND RISING HEIGHTS ALOFT. ON
MONDAY...DESPITE BEING UNDER THE SUBSIDENCE OF THE RISING HEIGHTS
ALOFT...NEARLY EVERY MODEL DEPICTS ISOLATED TO SCATTERED SHOWER AND
THUNDERSTORM DEVELOPMENT BETWEEN 18Z-00Z OVER THE FORECAST AREA.
THE REASONING FOR THE PRECIPITATION IS A COMBINATION OF FACTORS:
1. SOUTHEAST WINDS ADVECTING IN 70+ SURFACE DEWPOINTS...WHICH ARE
ACCOMPANYING THE BERMUDA HIGH AND ENHANCED BY EVAPOTRANSPORATION
FROM VEGETATION.
2. STREAM OF HIGHER PRECIPITABLE WATER VALUES OF 1.8 TO 2 INCHES
COMING UP OUT OF GEORGIA AND ALABAMA CURRENTLY.
3. DAYTIME HEATING COMBINING WITH THE HIGHER DEWPOINTS TO BUILD UP
INSTABILITY. MIXING TO 850MB TEMPS OF 16-17C SHOULD YIELD HIGHS IN
THE MID TO UPPER 80S.
4. SOUNDINGS DEPICT NO CAPPING
LOOKING AT VARIOUS PRESSURE LEVELS FOR CONVERGENCE...IT IS VERY
DIFFICULT TO FIND ANY. THUS...IT APPEARS THE LACK OF CAPPING AND THE
HIGHER DEEPER MOISTURE ITSELF WILL RESULT IN POP UP SHOWERS AND
THUNDERSTORMS. 0-6KM SHEAR VALUES OF LESS THAN 20 KT MEANS THESE
STORMS ARE GOING TO BE PULSE AND NON-SEVERE...WITH OUTFLOWS
PRODUCING ADDITIONAL SHOWERS AND THUNDERSTORMS. MAIN CONCERN WITH
THIS PRECIPITATION IS BRIEF HEAVY RAIN GIVEN THE PRECIPITABLE WATER
VALUES AND DEEP WARM CLOUD DEPTHS.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 250 PM CDT SUN JUL 14 2013
THE RETROGRESSION 500MB PATTERN CONTINUES FROM THE SHORT TERM PERIOD
RIGHT INTO NEXT WEEKEND. 14.12Z ECMWF/CANADIAN/GFS AND 14.00Z ECMWF
ENSEMBLE MEAN ALL SHOW THAT THE BERMUDA HIGH WILL SLOWLY MOVE
WESTWARD THROUGH THE WEEK...SUCH THAT BY LATE FRIDAY INTO THE
WEEKEND TROUGHING DOMINATES MUCH OF CANADA INTO THE WESTERN GREAT
LAKES REGION.
MONDAY NIGHT THROUGH WEDNESDAY...
CONVECTION THAT FORMED MONDAY AFTERNOON SHOULD DISSIPATE PRETTY
QUICK IN THE EVENING...LIKELY BY 03Z...AS THE LOSS OF DAYTIME
HEATING DIMINISHES THE INSTABILITY. THE REST OF THE NIGHT INTO
TUESDAY MORNING LOOKS DRY WITH THE MAIN FORCING FOR NOCTURNAL
CONVECTION WELL OFF TO THE NORTHWEST IN THE DAKOTAS. A SIMILAR SETUP
TO MONDAY AFTERNOON LOOKS TO OCCUR FOR TUESDAY AFTERNOON WITH
DEWPOINTS IN THE UPPER 60S TO LOW 70S...HIGHS A FEW DEGREES WARMER
GIVEN 850MB TEMPS PROGGED BETWEEN 18-19C...AND HIGHER CAPE VALUES
DUE TO THESE READINGS. HOWEVER...MODELS ARE MUCH LESS AGGRESSIVE
WITH QPF...AND THIS APPEARS TO STEM FROM PRECIPITABLE WATER VALUES
THAT ARE 0.25-0.5 INCH LOWER. GIVEN THAT THE 14.12Z NAM WHICH IS
USUALLY AGGRESSIVE IN THESE SCENARIOS AND HAPPENS TO BE DRY...AND
COLLABORATION WITH SURROUNDING OFFICES...WENT DRY FOR TUESDAY.
SHOWERS AND THUNDERSTORMS STILL LOOK POSSIBLE NORTH AND EAST OF THE
FORECAST AREA...ASSOCIATED WITH LAKE BREEZES RUNNING INTO THE
UNSTABLE AIR. A COMPLETE REPEAT OF THE WEATHER HAPPENS TUESDAY NIGHT
AND WEDNESDAY...AND HERE AGAIN MODELS ARE NOT THAT AGGRESSIVE WITH
QPF WEDNESDAY AFTERNOON STEMMING FROM SIMILAR PRECIPITABLE WATER
VALUES TO TUESDAY. REMOVED THE 20 PERCENT CHANCES FOR WEDNESDAY.
SAFE TO SAY THAT IF INDEED NO PRECIPITATION HAPPENS TUESDAY...
WEDNESDAY WILL END UP DRY TOO. HIGHS ON WEDNESDAY ARE LIKELY TO BE
SIMILAR TO TUESDAY WITH 850MB TEMPS HOVERING AROUND 19C...YIELDING
READINGS IN THE UPPER 80S TO LOWER 90S.
WITH TUESDAY AND WEDNESDAY AFTERNOON DEWPOINTS IN THE UPPER 60S TO
LOWER 70S AND HIGHS IN UPPER 80S TO LOWER 90S...HEAT INDICES ARE
LIKELY TO CLIMB INTO THE 95-100 RANGE. THESE ARE JUST UNDER HEAT
ADVISORY CRITERIA. SHOULD EITHER DEWPOINTS OR TEMPERATURES GET
HIGHER THAN FORECAST...HEAT ADVISORIES MAY BE REQUIRED.
WEDNESDAY NIGHT THROUGH SUNDAY...
THE PROGGED SWITCH IN THE UPPER FLOW TO MORE NORTHWESTERLY ALLOWS
A COLD FRONT SITUATED OVER NORTHERN MN AND UPPER MI ON WEDNESDAY
TO SLOWLY DRIFT SOUTH. THE TIMING OF WHEN THIS BOUNDARY CROSSES
THE FORECAST AREA LOOKS TO BE MODULATED BY A SHORTWAVE DROPPING
THROUGH NORTH DAKOTA...WHICH COULD STALL OR EVEN SEND THE FRONT
BACK NORTHWARD THURSDAY NIGHT AS SUGGESTED BY THE 14.00Z/14.12Z
ECMWF. MOST MODELS AGREE ON A TIMING OF THE COLD FRONT CROSSING
THE AREA FRIDAY INTO FRIDAY EVENING...WITH PERHAPS THE FRONT
COMING INTO NORTHERN SECTIONS OF THE FORECAST AREA WEDNESDAY
NIGHT. GIVEN PLENTIFUL INSTABILITY IN PLACE AHEAD OF AND AROUND
THE BOUNDARY...AS WELL AS A PLUME OF HIGHER PRECIPITABLE WATER
VALUES ON THE ORDER OF 1.75-2 INCHES...DEFINITELY NEED CHANCES OF
SHOWERS AND THUNDERSTORMS. THERE ARE INDICATIONS OF POSSIBLE MCS
ACTIVITY TOO...ESPECIALLY THURSDAY AFTERNOON AND NIGHT NORTH OF
I-90 WHICH IS WHERE CHANCES OF PRECIPITATION ARE ON THE ORDER OF
50-60. ONE PORTION OF THE FORECAST WHERE CHANCES MAY BE ABLE TO BE
REMOVED IS FRIDAY NIGHT...SINCE THERE ARE SOME INDICATIONS OF THE
FRONT AND ASSOCIATED CONVECTION GETTING OUT OF THE AREA IN TIME.
HIGH PRESSURE BUILDS IN FOR SATURDAY AND SATURDAY NIGHT...BRINGING
DRIER CONDITIONS. UNCERTAINTY INCREASES FOR SUNDAY WITH
INDICATIONS OF SOME SHORTWAVE TROUGH DROPPING THROUGH IN THE
NORTHWEST FLOW. HAVE FOLLOWED A MODEL CONSENSUS OF 20-40 PERCENT
CHANCES FOR NOW.
SOME SEVERE WEATHER IS POSSIBLE THURSDAY THROUGH FRIDAY...WITH 0-6KM
SHEAR VALUES PROGGED OF 30-35 KT ALONG THE COLD FRONT. DAMAGING
WINDS AND HEAVY RAIN WOULD APPEAR TO BE THE MAIN HAZARDS. LOCATIONS
NORTH OF I-90 SEEM TO BE CENTERED ON HAVING THE MOST RAIN DURING
THIS PERIOD...WHICH IS AN AREA THAT NOT ONLY CAN HANDLE THE RAIN BUT
NEEDS IT.
TEMPERATURES THURSDAY THROUGH FRIDAY ARE QUITE TRICKY. 850MB TEMPS
UPWARDS OF 20C COULD EASILY SUPPORT HIGHS IN THE LOW TO EVEN PERHAPS
MID 90S...AND WITH DEWPOINTS UP IN THE LOW 70S WOULD YIELD HEAT
INDICES AGAIN IN THE 95-100 RANGE. HOWEVER...THERE IS CONVECTION TO
WORRY ABOUT...ESPECIALLY ON FRIDAY. THUS...HIGH TEMPERATURES ARE
ONLY FORECAST IN THE MID 80S TO LOW 90S AT THIS TIME. 850MB TEMPS
FALLING INTO THE 13-15C RANGE FOR SATURDAY AND ONLY CLIMBING ABOUT
1C HIGHER ON SUNDAY WILL RESULT IN COOLER TEMPERATURES...UPPER 70S
TO MID 80S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1230 PM CDT SUN JUL 14 2013
MORE LOW LEVEL MOISTURE HAS WORKED IN AS DRIER AREAS ARE SHUNTED OR
SQUEEZED OUT FOR THE TIME BEING. THIS HAS RESULTED IN WIDESPREAD
CUMULUS DEVELOPMENT THAT COULD ACTUALLY PRODUCE SOME VFR CEILINGS
FOR A TIME THIS AFTERNOON BEFORE THEY DISSIPATE EARLY THIS EVENING.
HIGHER DEW POINTS COULD ALSO LEAD TO MORE LIGHT FOG OVERNIGHT WITH
SOME AREAS REACHING MVFR CONDITIONS FOR A FEW HOURS BEFORE DAYBREAK
MONDAY. FOG COULD BE MORE DENSE IN SOUTHWEST AND CENTRAL WISCONSIN
IN FAVORED VALLEYS.
MORE DIURNAL CUMULUS EXPECTED MONDAY...AND PERHAPS EVEN ENOUGH
INSTABILITY FOR A FEW POP UP SHOWERS BUT WILL NOT INTRODUCE INTO
TAFS THAT FAR OUT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....SHEA
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1230 PM CDT SUN JUL 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 322 AM CDT SUN JUL 14 2013
THE MAIN FOCUS FOR TODAY IS ON TEMPERATURES AND CLOUD COVER AS
UPPER LEVEL RIDGING PUSHES IN FROM THE EAST.
CURRENTLY...SOME SCATTERED CONVECTION HAS DEVELOPED ALONG THE
DEFORMATION BAND OF A WEAK 500MB TROUGH THAT EXTENDS FROM
NORTHWEST WISCONSIN DOWN INTO WESTERN IOWA. EXTENSIVE MID TO UPPER
LEVEL CLOUD COVER COMES WITH THIS BAND AND HAS BEEN SLOW TO SHIFT
TO THE WEST THIS MORNING. THE 14.06Z RAP 700-400MB RH FIELDS SEEM
TO HAVE A GOOD HANDLE ON THIS CLOUD COVER AND DOES CONTINUE TO
SHIFT THIS CLOUD DECK AND CONVECTION TO THE WEST QUICKLY THIS
MORNING.
HIGH TEMPERATURES FOR TODAY ARE THE NEXT QUESTION AS MUCH OF THE
REGION SHOULD HAVE FULL SUN. 14.06Z RAP AND 14.00Z NAM/GFS
SOUNDINGS INDICATE THAT THE HIGHEST POSSIBLE MIXING WOULD COME
FROM AROUND 875-850MB. WHEN MIXING DOWN A PARCEL FROM THAT LEVEL
OR LOWER...IT SHOWS THAT HIGHS TODAY HAVE A MAX OUT IN THE MID TO
UPPER 80S. MAY SEE SOME FAIR WEATHER CU FORMING BUT THE LOW LEVEL
MOISTURE DOES NOT REALLY START RAMPING UP UNTIL MONDAY...SO THINK
THAT IT WILL BE FEW AND FAR BETWEEN FOR ANY OF THAT DEVELOPMENT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 322 AM CDT SUN JUL 14 2013
THE MAIN FOCUS FOR THE UPCOMING WEEK IS WITH THE CHANCES FOR RAIN
ALONG WITH DAILY TEMPERATURES.
DESPITE A MAINLY SUBSIDENT ENVIRONMENT MONDAY THROUGH
WEDNESDAY...INCREASING LOW LEVEL MOISTURE WILL LEAD TO A MORE HUMID
AIR MASS THAT WILL HAVE THE POTENTIAL OF PRODUCING SOME VERY ISOLATED
SHOWERS AND THUNDERSTORMS. CONFIDENCE IS NOT VERY HIGH WITH WHETHER
THEY WILL EVEN DEVELOP BASED ON THE LACK OF A FORCING
MECHANISM...BUT GUIDANCE HAS BEEN CONSISTENT WITH SHOWING SOME
PRECIPITATION FORMING IN THE AFTERNOON DURING DIURNAL PEAK HEATING.
HAVE DECIDED TO HONOR THIS WITH SOME 20 PERCENT CHANCES OF
PRECIPITATION MONDAY/TUESDAY/WEDNESDAY AFTERNOON AS A RESULT. ANY
DEEP LAYER SHEAR IS NON-EXISTENT...SO THIS WILL BE PULSEY/CELLULAR
CONVECTION THAT IS BRIEF AND NON- SEVERE.
THE HIGHER CHANCES FOR PRECIPITATION WILL COME LATER IN THE WEEK
AS A COLD FRONT SAGS SOUTH FROM ALONG THE US/CANADIAN BORDER. THE
14.00Z GFS/ECMWF/GEM ALL ANGLE THIS FRONT FROM NEAR FARGO TO THE
EAST TOWARD NORTH CENTRAL WISCONSIN ON THURSDAY WITH CONVECTION
EXPECTED TO DEVELOP ALONG THIS REGION. THE FRONT IS THEN EXPECTED
TO GET A PUSH TO THE SOUTH FRIDAY INTO SATURDAY WITH THE GFS BEING
MUCH MORE WIDESPREAD ON ITS PRECIPITATION WHEN COMPARED TO THE
LATEST ECMWF RUN. HOWEVER...THE TIMING OF THIS FROPA STILL LOOKS
FAIRLY CONSISTENT BETWEEN THESE MODELS...SO HAVE SOME ABOVE
AVERAGE CONFIDENCE IN THE TIMING OF THE HIGHEST PROBABILITIES OF
PRECIPITATION BASED ON THIS FROPA.
LOW LEVEL TEMPERATURES APPEAR TO CLIMB GRADUALLY THROUGH THE WEEK
WITH 850MB TEMPERATURES JUMPING FROM AROUND +16C TODAY TO +20C BY
THURSDAY NIGHT AND 925MB TEMPERATURES GOING FROM +21C TODAY TO
+27C BY THURSDAY NIGHT. WITH MAINLY SUNNY SKIES...TEMPERATURES
SHOULD BE ABLE TO REACH 90F TUESDAY THROUGH THURSDAY AND PERHAPS
FRIDAY IF THE FRONT TAKES LONGER TO GET THROUGH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1230 PM CDT SUN JUL 14 2013
MORE LOW LEVEL MOISTURE HAS WORKED IN AS DRIER AREAS ARE SHUNTED OR
SQUEEZED OUT FOR THE TIME BEING. THIS HAS RESULTED IN WIDESPREAD
CUMULUS DEVELOPMENT THAT COULD ACTUALLY PRODUCE SOME VFR CEILINGS
FOR A TIME THIS AFTERNOON BEFORE THEY DISSIPATE EARLY THIS EVENING.
HIGHER DEW POINTS COULD ALSO LEAD TO MORE LIGHT FOG OVERNIGHT WITH
SOME AREAS REACHING MVFR CONDITIONS FOR A FEW HOURS BEFORE DAYBREAK
MONDAY. FOG COULD BE MORE DENSE IN SOUTHWEST AND CENTRAL WISCONSIN
IN FAVORED VALLEYS.
MORE DIURNAL CUMULUS EXPECTED MONDAY...AND PERHAPS EVEN ENOUGH
INSTABILITY FOR A FEW POP UP SHOWERS BUT WILL NOT INTRODUCE INTO
TAFS THAT FAR OUT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM....HALBACH
AVIATION.....SHEA
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
613 AM CDT SUN JUL 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 322 AM CDT SUN JUL 14 2013
THE MAIN FOCUS FOR TODAY IS ON TEMPERATURES AND CLOUD COVER AS
UPPER LEVEL RIDGING PUSHES IN FROM THE EAST.
CURRENTLY...SOME SCATTERED CONVECTION HAS DEVELOPED ALONG THE
DEFORMATION BAND OF A WEAK 500MB TROUGH THAT EXTENDS FROM
NORTHWEST WISCONSIN DOWN INTO WESTERN IOWA. EXTENSIVE MID TO UPPER
LEVEL CLOUD COVER COMES WITH THIS BAND AND HAS BEEN SLOW TO SHIFT
TO THE WEST THIS MORNING. THE 14.06Z RAP 700-400MB RH FIELDS SEEM
TO HAVE A GOOD HANDLE ON THIS CLOUD COVER AND DOES CONTINUE TO
SHIFT THIS CLOUD DECK AND CONVECTION TO THE WEST QUICKLY THIS
MORNING.
HIGH TEMPERATURES FOR TODAY ARE THE NEXT QUESTION AS MUCH OF THE
REGION SHOULD HAVE FULL SUN. 14.06Z RAP AND 14.00Z NAM/GFS
SOUNDINGS INDICATE THAT THE HIGHEST POSSIBLE MIXING WOULD COME
FROM AROUND 875-850MB. WHEN MIXING DOWN A PARCEL FROM THAT LEVEL
OR LOWER...IT SHOWS THAT HIGHS TODAY HAVE A MAX OUT IN THE MID TO
UPPER 80S. MAY SEE SOME FAIR WEATHER CU FORMING BUT THE LOW LEVEL
MOISTURE DOES NOT REALLY START RAMPING UP UNTIL MONDAY...SO THINK
THAT IT WILL BE FEW AND FAR BETWEEN FOR ANY OF THAT DEVELOPMENT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 322 AM CDT SUN JUL 14 2013
THE MAIN FOCUS FOR THE UPCOMING WEEK IS WITH THE CHANCES FOR RAIN
ALONG WITH DAILY TEMPERATURES.
DESPITE A MAINLY SUBSIDENT ENVIRONMENT MONDAY THROUGH
WEDNESDAY...INCREASING LOW LEVEL MOISTURE WILL LEAD TO A MORE HUMID AIR
MASS THAT WILL HAVE THE POTENTIAL OF PRODUCING SOME VERY ISOLATED
SHOWERS AND THUNDERSTORMS. CONFIDENCE IS NOT VERY HIGH WITH
WHETHER THEY WILL EVEN DEVELOP BASED ON THE LACK OF A FORCING
MECHANISM...BUT GUIDANCE HAS BEEN CONSISTENT WITH SHOWING SOME
PRECIPITATION FORMING IN THE AFTERNOON DURING DIURNAL PEAK
HEATING. HAVE DECIDED TO HONOR THIS WITH SOME 20 PERCENT CHANCES
OF PRECIPITATION MONDAY/TUESDAY/WEDNESDAY AFTERNOON AS A RESULT.
ANY DEEP LAYER SHEAR IS NON-EXISTENT...SO THIS WILL BE
PULSEY/CELLULAR CONVECTION THAT IS BRIEF AND NON- SEVERE.
THE HIGHER CHANCES FOR PRECIPITATION WILL COME LATER IN THE WEEK
AS A COLD FRONT SAGS SOUTH FROM ALONG THE US/CANADIAN BORDER. THE
14.00Z GFS/ECMWF/GEM ALL ANGLE THIS FRONT FROM NEAR FARGO TO THE
EAST TOWARD NORTH CENTRAL WISCONSIN ON THURSDAY WITH CONVECTION
EXPECTED TO DEVELOP ALONG THIS REGION. THE FRONT IS THEN EXPECTED
TO GET A PUSH TO THE SOUTH FRIDAY INTO SATURDAY WITH THE GFS BEING
MUCH MORE WIDESPREAD ON ITS PRECIPITATION WHEN COMPARED TO THE
LATEST ECMWF RUN. HOWEVER...THE TIMING OF THIS FROPA STILL LOOKS
FAIRLY CONSISTENT BETWEEN THESE MODELS...SO HAVE SOME ABOVE
AVERAGE CONFIDENCE IN THE TIMING OF THE HIGHEST PROBABILITIES OF
PRECIPITATION BASED ON THIS FROPA.
LOW LEVEL TEMPERATURES APPEAR TO CLIMB GRADUALLY THROUGH THE WEEK
WITH 850MB TEMPERATURES JUMPING FROM AROUND +16C TODAY TO +20C BY
THURSDAY NIGHT AND 925MB TEMPERATURES GOING FROM +21C TODAY TO
+27C BY THURSDAY NIGHT. WITH MAINLY SUNNY SKIES...TEMPERATURES
SHOULD BE ABLE TO REACH 90F TUESDAY THROUGH THURSDAY AND PERHAPS
FRIDAY IF THE FRONT TAKES LONGER TO GET THROUGH.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
613 AM CDT SUN JUL 14 2013
GENERALLY GOOD VFR CONDITIONS EXPECTED TODAY/TONIGHT AS SEASONABLY
DRY HIGH PRESSURE LOCATED OVER THE GREAT LAKES REMAINS IN CONTROL OF
THE AREA/S WEATHER. WITH PERSISTENT SOUTHERLY LOW LEVEL FLOW...LOWER
LEVEL MOISTURE WILL GRADUALLY INCREASE. DIURNAL WARMING IS EXPECTED
TO PRODUCE SCT 4K-5K FT CUMULUS FOR THE AFTERNOON INTO EARLY EVENING
HOURS...OTHERWISE ANY CLOUDS LOOKING TO BE ABOVE 10K FT THRU TONIGHT.
LIGHT WINDS AND MOSTLY CLEAR SKIES TONIGHT COUPLED WITH THE
INCREASING BOUNDARY LAYER MOISTURE RAISE CONCERNS FOR SOME BR IN THE
09-13Z TIME-FRAME. WITH THE CENTER OF THE HIGH WELL OFF TO THE EAST
OF THE AREA AND SOME PERSISTENT BUT LIGHT SOUTH-SOUTHEAST GRADIENT
WINDS TONIGHT...LEFT ANY MENTION OF MVFR BR OUT OF THE END OF THE
TAF PERIOD FOR NOW.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM....HALBACH
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
322 AM CDT SUN JUL 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 322 AM CDT SUN JUL 14 2013
THE MAIN FOCUS FOR TODAY IS ON TEMPERATURES AND CLOUD COVER AS
UPPER LEVEL RIDGING PUSHES IN FROM THE EAST.
CURRENTLY...SOME SCATTERED CONVECTION HAS DEVELOPED ALONG THE
DEFORMATION BAND OF A WEAK 500MB TROUGH THAT EXTENDS FROM
NORTHWEST WISCONSIN DOWN INTO WESTERN IOWA. EXTENSIVE MID TO UPPER
LEVEL CLOUD COVER COMES WITH THIS BAND AND HAS BEEN SLOW TO SHIFT
TO THE WEST THIS MORNING. THE 14.06Z RAP 700-400MB RH FIELDS SEEM
TO HAVE A GOOD HANDLE ON THIS CLOUD COVER AND DOES CONTINUE TO
SHIFT THIS CLOUD DECK AND CONVECTION TO THE WEST QUICKLY THIS
MORNING.
HIGH TEMPERATURES FOR TODAY ARE THE NEXT QUESTION AS MUCH OF THE
REGION SHOULD HAVE FULL SUN. 14.06Z RAP AND 14.00Z NAM/GFS
SOUNDINGS INDICATE THAT THE HIGHEST POSSIBLE MIXING WOULD COME
FROM AROUND 875-850MB. WHEN MIXING DOWN A PARCEL FROM THAT LEVEL
OR LOWER...IT SHOWS THAT HIGHS TODAY HAVE A MAX OUT IN THE MID TO
UPPER 80S. MAY SEE SOME FAIR WEATHER CU FORMING BUT THE LOW LEVEL
MOISTURE DOES NOT REALLY START RAMPING UP UNTIL MONDAY...SO THINK
THAT IT WILL BE FEW AND FAR BETWEEN FOR ANY OF THAT DEVELOPMENT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 322 AM CDT SUN JUL 14 2013
THE MAIN FOCUS FOR THE UPCOMING WEEK IS WITH THE CHANCES FOR RAIN
ALONG WITH DAILY TEMPERATURES.
DESPITE A MAINLY SUBSIDENT ENVIRONMENT MONDAY THROUGH
WEDNESDAY...INCREASING LOW LEVEL MOISTURE WILL LEAD TO A MORE HUMID AIR
MASS THAT WILL HAVE THE POTENTIAL OF PRODUCING SOME VERY ISOLATED
SHOWERS AND THUNDERSTORMS. CONFIDENCE IS NOT VERY HIGH WITH
WHETHER THEY WILL EVEN DEVELOP BASED ON THE LACK OF A FORCING
MECHANISM...BUT GUIDANCE HAS BEEN CONSISTENT WITH SHOWING SOME
PRECIPITATION FORMING IN THE AFTERNOON DURING DIURNAL PEAK
HEATING. HAVE DECIDED TO HONOR THIS WITH SOME 20 PERCENT CHANCES
OF PRECIPITATION MONDAY/TUESDAY/WEDNESDAY AFTERNOON AS A RESULT.
ANY DEEP LAYER SHEAR IS NON-EXISTENT...SO THIS WILL BE
PULSEY/CELLULAR CONVECTION THAT IS BRIEF AND NON- SEVERE.
THE HIGHER CHANCES FOR PRECIPITATION WILL COME LATER IN THE WEEK
AS A COLD FRONT SAGS SOUTH FROM ALONG THE US/CANADIAN BORDER. THE
14.00Z GFS/ECMWF/GEM ALL ANGLE THIS FRONT FROM NEAR FARGO TO THE
EAST TOWARD NORTH CENTRAL WISCONSIN ON THURSDAY WITH CONVECTION
EXPECTED TO DEVELOP ALONG THIS REGION. THE FRONT IS THEN EXPECTED
TO GET A PUSH TO THE SOUTH FRIDAY INTO SATURDAY WITH THE GFS BEING
MUCH MORE WIDESPREAD ON ITS PRECIPITATION WHEN COMPARED TO THE
LATEST ECMWF RUN. HOWEVER...THE TIMING OF THIS FROPA STILL LOOKS
FAIRLY CONSISTENT BETWEEN THESE MODELS...SO HAVE SOME ABOVE
AVERAGE CONFIDENCE IN THE TIMING OF THE HIGHEST PROBABILITIES OF
PRECIPITATION BASED ON THIS FROPA.
LOW LEVEL TEMPERATURES APPEAR TO CLIMB GRADUALLY THROUGH THE WEEK
WITH 850MB TEMPERATURES JUMPING FROM AROUND +16C TODAY TO +20C BY
THURSDAY NIGHT AND 925MB TEMPERATURES GOING FROM +21C TODAY TO
+27C BY THURSDAY NIGHT. WITH MAINLY SUNNY SKIES...TEMPERATURES
SHOULD BE ABLE TO REACH 90F TUESDAY THROUGH THURSDAY AND PERHAPS
FRIDAY IF THE FRONT TAKES LONGER TO GET THROUGH.
&&
.AVIATION...THROUGH 06Z MONDAY
1124 PM CDT SAT JUL 13 2013
AREA REMAINS CAUGHT BETWEEN THE WESTERLIES TO OUR NORTH AND THE WESTWARD
MOVING SHORT WAVE TROUGH TRACKING INTO EASTERN MISSOURI. WITH NO UPPER
LEVEL STEERING FLOW...WE ARE CAUGHT WITH A NARROW BAND OF MID AND
HIGH LEVEL MOISTURE. THIS WILL LINGER THROUGH THE NIGHT...BUT THE
SOUTHERN WAVE WILL ADVECT SOME DRIER AIR IN FROM THE EAST SLOWLY
OVERNIGHT. WITH SOMEWHAT COOL TEMPERATURES AND DEW POINTS LINGERING
IN THE LOWER 60S...COULD SEE SOME LIGHT MIST FOR A FEW HOURS
AROUND SUNRISE. AS THE WAVE MAKES WESTWARD PROGRESS SUNDAY...HIGH
CLOUD SHOULD DIMINISH AND MOVE WEST. HOWEVER LOW LEVEL MOISTURE
WILL BE SLOWLY ON THE INCREASE...SO SOME CUMULUS DEVELOPMENT IS
POSSIBLE DIURNALLY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...MW
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
140 AM EDT TUE JUL 16 2013
.UPDATE...
22Z SURFACE ANALYSIS SHOWS HIGH PRESSURE BUILDING IN FROM THE NE
ACROSS THE CWFA. OVER THE LAST FEW HOURS...MOST OF THE STRONGER
AFTERNOON CONVECTION HAS MOVED OFF TO THE WEST. ADDITIONAL SHOWERS
IN THE EAST ARE MOVING INTO AREAS THAT HAVE BEEN SLIGHTLY
STABILIZED WITH EARLIER ACTIVITY. THE LATEST RUNS OF THE HRRR SHOW
A DIMINISHING TREND IN CONVECTION AFTER 02Z. THIS SEEMS REASONABLE
AND HAVE FOLLOWED CLOSELY. HAVE ALSO REMOVED ALL MENTION OF
ISOLATED POPS AFTER 02AM. HIGH RESOLUTION MODELS ALSO SUPPORT
THIS.
&&
.PREV DISCUSSION... /ISSUED 346 PM EDT MON JUL 15 2013/
SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
A SLUG OF ATLANTIC MOISTURE WILL CONTINUE TO ADVECT WESTWARD ACROSS
THE CWA THIS AFTERNOON INTO EVENING ALONG THE SOUTHERN EXTEND OF AN
UPPER HIGH CENTERED OVER THE OHIO VALLEY. WHILE MLCAPE VALUES ARE
HIGHER TODAY THAN YESTERDAY AT NEAR 2000 J/KG...PWATS ARE NEAR 2.0
INCHES AGAIN AND DEVELOPMENT IS LARGELY TROPICAL IN NATURE. THERE
COULD BE SOME ISOLATED STRONG STORMS BUT NOT EXPECTED ANYTHING
SEVERE.
WHILE THE UPPER RIDGE SLOWLY DAMPENS AND RETROGRADES WEST THROUGH
TUESDAY...CANNOT RULE OUT A CHANCE OF SHOWERS AND THUNDERSTORMS
MAINLY IN THE AFTERNOON WITH CONTINUED EASTERLY FETCH AND DECENT
CAPE. HAVE GONE WITH CHANCE POPS SOUTH AND SLIGHT ELSEWHERE. ANOTHER
LOBE OF ENHANCED DEEPER MOISTURE APPROACHES THE NORTHEAST PART OF
THE AREA TUESDAY NIGHT SO HAVE INCREASED CLOUD COVERAGE...WHILE POPS
SHOULD BE ON THE RISE INTO WEDNESDAY.
FOR TEMPS...USED BLEND OF GUIDANCE AS THIS HAS VERIFIED WELL
RECENTLY. MAX VALUES SHOULD REBOUND TO BACK NEAR NORMAL TUESDAY IN
THE UPPER 80S TO LOW 90S.
BAKER
LONG TERM /WEDNESDAY THROUGH MONDAY/...
NO MAJOR CHANGES IN THE CURRENT EXTENDED FORECAST. HIGH PRESSURE
ALOFT WILL BE OVER THE OH- MID MS VALLEYS TO START THE LONG TERM.
A MOIST AIRMASS WILL STILL BE IN PLACE AS A DEEP EASTERLY FLOW
PATTERN PERSISTS. THIS SHOULD ALLOW A MORE DIURNAL TENDENCY TO ANY
CONVECTION TUESDAY NIGHT AND WEDNESDAY.
THIS PATTERN LOOKS TO CONTINUE ON THURSDAY AND FRIDAY BUT WITH THE
UPPER RIDGE WEAKENING AND THE UPPER FLOW BECOMING MORE WESTERLY FOR
SATURDAY INTO MONDAY. SCATTERED SHOWERS AND THUNDERSTORMS CAN BE
EXPECTED FOR MOST AREAS THROUGH MONDAY WITH THE GREATEST COVERAGE
IN THE AFTERNOON AND EVENING HOURS. THE POTENTIAL FOR SOME
ENHANCEMENT FROM SHORT WAVE ENERGY WILL INCREASE FROM SATURDAY ON
ALONG WITH DEEPER MOISTURE AVAILABLE. ALL IN ALL TEMPERATURES
SHOULD GENERALLY BE CLOSE TO NORMAL WITH THE HIGHS SLIGHTLY BELOW
NORMAL LATER IN THE PERIOD.
BDL/01
&&
.AVIATION...
06Z UPDATE...
SOME MVFR CLOUDS POSSIBLE TOWARD 09Z...AND MAY BE SOME IFR FORMING
ALSO BUT DO NOT EXPECT IT TO BE WIDESPREAD. STRATUS IMPROVING TO VFR
BY 15Z. LIGHT EAST WINDS UNTIL 14Z THEN INCREASING TO 10 TO 15KT.
WIDELY SCATTERED SHOWERS AND THUNDERSTORMS MAINLY THIS AFTERNOON.
WILL LEAVE OUT OF TAFS FOR NOW SINCE POPS ONLY 20 TO 30 PERCENT.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM CONFIDENCE FOR CIGS. HIGH CONFIDENCE REMAINING ELEMENTS.
&&
41
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 70 89 70 91 / 20 20 20 50
ATLANTA 70 88 73 89 / 30 20 20 50
BLAIRSVILLE 65 87 67 86 / 20 20 20 50
CARTERSVILLE 70 90 69 90 / 30 20 20 50
COLUMBUS 72 90 73 91 / 30 30 20 30
GAINESVILLE 70 88 72 88 / 20 20 20 50
MACON 70 89 70 91 / 30 30 20 30
ROME 70 91 69 91 / 30 20 20 50
PEACHTREE CITY 69 87 68 89 / 30 20 20 50
VIDALIA 72 90 72 93 / 30 30 30 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1201 AM MDT TUE JUL 16 2013
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 138 PM MDT MON JUL 15 2013
LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOW 581 DM CLOSED LOW
CENTERED OVER SW OKLAHOMA...WITH A 599 DM RIDGE ACROSS THE EASTERN
CONUS EXTENDING WEST ACROSS THE NORTHERN PLAINS. WV IMAGERY SHOWS
MOISTURE CONTINUING TO ROTATE AROUND EASTERN EXTEND OF CLOSED LOW
INTO SOUTHERN KS. RAP/LATEST NAM SHOW A CURVED JET STRUCTURE ACROSS
THE NORTHERN PART OF CLOSED LOW OVER SW KS AND SEVERAL VORT MAXES
ROTATING THROUGH THE NORTHERN EXTENT OF THIS LOW. COMPOSITE RADAR
SHOWS SHOWER ACTIVITY HAVING DEVELOPED WITH THESE FEATURES MOVING TO
ACROSS CENTRAL AND SOUTHWEST KANSAS. VIS SATELLITE SHOWS A
WIDESPREAD CU FIELD IN PLACE ACROSS OUR CWA THAT HAS DEVELOPED WITH
DAYTIME HEATING AND COLD POOL ALOFT.
LATEST SHORT RANGE GUIDANCE SHOWS THE ACTIVITY CURRENTLY SOUTH AND
EAST OF THE CWA FALLING APART BY 00Z AS IT MOVES TOWARDS OUR CWA. AT
THIS POINT I AM NOT SURE WE WILL ACTUALLY SEE ANY SHOWERS DEVELOP
WITH CU FIELD...THOUGH UNTIL WE LOOSE DAYTIME HEATING I COULDNT RULE
OUT SHOWERS SPREADING INTO THE SOUTHERN HALF CONSIDERING RADAR
TRENDS...AND AT LEAST SOME LARGE SCALE FORCING STILL IN PLACE JUST TO
OUR SOUTH. I DO NOT EXPECT THIS TO BE WIDESPREAD AND SHOULD QUICKLY
END AS WE LOOSE FAVORABLE LOW LEVEL LAPSE RATES DUE TO DIURNAL
COOLING.
SOUTHERLY FLOW WILL KEEP BL MOISTURE IN PLACE OVERNIGHT AND
TUESDAY...AND THERE IS SOME INDICATION OF A FEW SHOWERS ACROSS
SOUTHERN KS...POSSIBLY INTO OUR CWA AS UPPER LOW CONTINUES TO SLOWLY
MOVE WEST. WITH LITTLE IN THE WAY OF INSTABILITY AND STRONG
SUBSIDENCE BUILDING IN FROM THE NORTH TONIGHT I DECIDED TO KEEP
FORECAST DRY. WE DO BEGIN TO SEE A SIMILAR SET UP AS THIS AFTERNOON
REGARDING INCREASING LAPSE RATES BELOW COLD POOL...HOWEVER WITH
RIDGE BEGINNING TO HOLD MORE INFLUENCE AND DRIER AIR MOVING INTO THE
REGION ALOFT...I DECIDED TO KEEP POPS SILENT FOR NOW. I DID KEEP
PATCHY FOG MENTION IN THE FORECAST FOR TUESDAY MORNING...AND GOOD BL
MOISTURE ADVECTING IN FROM THE SOUTH. WITH BL WINDS
INCREASING...IF WE SEE SURFACE WINDS AROUND 10KT THE LOW LEVELS
MAY BE TOO MIXED FOR FOG DEVELOPMENT...SO I KEPT COVERAGE PATCHY.
THERE IS LITTLE CHANGE REGARDING THE AIR MASS OVER OUR CWA
TUESDAY...AND THERE ARE SIMILAR TRENDS REGARDING CLOUD COVER. TEMPS
ON TUESDAY SHOULD BE VERY SIMILAR TO TODAY...WITH HIGHS RANGING FROM
THE UPPER 70S WEST TO UPPER 80S EAST.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 244 PM MDT MON JUL 15 2013
DRY CONDITIONS WITH A SLOW WARMING TREND WILL BE THE DOMINANT
WEATHER PATTERN UNTIL THE OF THE WEEK AS THE HIGH PRESSURE OVER THE
EASTERN CONUS MOVES WEST TOWARD THE ROCKIES. WEDNESDAY AND THURSDAY
WILL BE WINDY AS 850MB WINDS NEAR 30KTS ARE ABLE TO MIX DOWN TO
THE GROUND AHEAD OF THE RETROGRADING RIDGE. PRECIPITATION CHANCES
RETURN FRIDAY THROUGH EARLY NEXT WEEK AS A FEW UPPER LEVEL
DISTURBANCES MOVE THROUGH THE NORTHWEST FLOW OVER THE AREA.
FRIDAY A WEAK FRONT/SURFACE TROUGH MOVES OVER THE AREA...COOLING THE
ABOVE NORMAL TEMPERATURES DOWN AND HELPING WITH PRECIP. CHANCES AS
AN UPPER LEVEL TROUGH ALSO MOVES THROUGH.
THE WEAK FRONT LINGERS OVER THE SOUTHERN PART OF THE AREA THROUGH
SATURDAY WHICH MAY AID IN CREATING SOME STORMS FOR THE AREA.
PRECIPITATION CHANCES LINGER THROUGH EARLY NEXT WEAK AS ANOTHER WEAK
UPPER LEVEL TROUGH MOVES ACROSS THE AREA.
TEMPERATURES THROUGH THE PERIOD WILL START OUT NEAR NORMAL THEN WARM
TO NEAR/ABOVE NORMAL BY THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1151 PM MDT MON JUL 15 2013
EXPECT MOSTLY VFR CONDITIONS TO PREVAIL AT MCK AND GLD SITES
THROUGH THE TAF PERIOD. BUT WITH LOW 60S DEWPOINT AIR STREAMING
IN AT THE SURFACE AND OVERNIGHT LOW TEMPERATURES EXPECTED TO BE
NEAR CURRENT DEWPOINTS ACROSS THE REGION...EXPECT MVFR CONDITIONS
DUE PRIMARILY TO A LOW CLOUDS DECK THAT BECOME MORE WIDESPREAD
ACROSS THE CENTRAL HIGH PLAINS REGION OVERNIGHT. AS WIND SPEEDS
DECREASE TOWARDS SUNRISE...COULD SEE SOME PATCHY FOG ALSO
DEVELOPING. EXPECT WINDS TO BE SSE...BUT IF THEY TURN TO HAVE A
MORE EASTERLY COMPONENT...COULD SEE IFR CONDITIONS WITH VISIBILITIES
DECREASING TO A MILE OR LESS DUE TO MORE WIDESPREAD FOG. WITH
CURRENT WIND DIRECTION AND SPEED FORECAST...HAVE KEPT CONDITIONS
MVFR BETWEEN 10Z-14Z AT BOTH MCK AND GLD WITH TEMPORARY 3SM
VISIBILITY AND A BROKEN CLOUD LAYER AT 015 AGL. GUSTY SOUTH TO
SOUTHEAST WINDS WILL RETURN BY MID MORNING...DISSIPATING ANY FOG
AND LOWER CLOUDS THROUGH THE DAY WITH A SCATTERED HIGHER CUMULUS
LAYER DEVELOPING DURING THE AFTERNOON.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JTL
AVIATION...LOCKHART
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
442 AM EDT TUE JUL 16 2013
.SYNOPSIS...
HOT AND HUMID CONDITIONS ARE EXPECTED THROUGH THE WEEK AS HIGH
PRESSURE DOMINATES THE WEATHER. THUNDERSTORM CHANCES WILL INCREASE
FRIDAY AND SATURDAY AS A COLD FRONT APPROACHES AND CROSSES THE
REGION.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
TEMPERATURES AND DEWPOINTS ACROSS THE FORECAST AREA ARE STRUGGLING
TO DROP EARLY THIS MORNING. THE HRRR AND THE LAMP SEEM TO BE
HANDLING THIS QUITE WELL...SO THEY WERE USED THROUGH THE DAY
TODAY. THIS BRINGS THE DEWPOINTS UP THROUGH THE AFTERNOON WHICH IN
TURN BRINGS APPARENT TEMPERATURES INTO THE MID TO UPPER 90S OVER
MY EASTERN OH...SOUTHWESTERN PA...AND NORTHERN WV PANHANDLE
COUNTIES. THUS...AN SPS WILL BE ISSUED WITH THE MORNING PACKAGE
FOR HOT TEMPERATURES AS IT WILL BE JUST UNDER HEAT ADVISORY
CRITERIA.
THE MID LEVEL HIGH WILL CONTINUE TO SHIFT WESTWARD TODAY ALLOWING
FOR THE CAP TO WEAKEN THIS AFTERNOON. THIS COULD ALLOW FOR A BIT
MORE THUNDERSTORM COVERAGE THAN YESTERDAY...MAINLY ALONG THE LAKE
BREEZE BOUNDARY TO THE NORTH AND IN THE HIGHER ELEVATIONS.
HOWEVER...THE HI RES MODELS ARE SUGGESTING THAT A FEW
SHOWERS/THUNDERSTORMS COULD DEVELOP A BIT FURTHER SOUTH AND
WEST...SO A ISOLATED THUNDERSTORM MENTION WAS ADDED TO ALL OF THE
FORECAST AREA BY LATE AFTERNOON. CONFIDENCE IN THIS COVERAGE
REMAINS LOW HOWEVER...ESPECIALLY OVER EASTERN OHIO...SO FELT AN
ISOLATED MENTION WOULD SUFFICE.
HIGH PRES WILL CONTINUE TO SLOWLY MOVE WESTWARD THROUGH THE
PERIOD. CONTINUED A SLIGHT CHANCE MENTION FOR THUNDERSTORMS NORTH
AND ALONG THE RIDGES WEDNESDAY. APPARENT TEMPERATURES WILL ONCE
AGAIN GET VERY CLOSE TO 100 DEGREES WEDNESDAY AFTERNOON. FOR
NOW...WILL CONTINUE TO HIGHLIGHT HOT...HUMID WEATHER IN THE HWO.
BIAS CORRECTED MOS WAS USED FOR TEMPERATURES...WITH ABOVE SEASONAL
VALUES EXPECTED BOTH DAY AND NIGHT.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
VERY HUMID AMS WILL PERSIST THRU THE WK OWING TO STAGNANT FLOW
AMID FLATTENING H5 RDG. BY THU...MID-LVL FLOW WILL INCR SLGTLY AS
JET STREAM ACRS CANADA SINKS EQUATORWARD.
CAP STILL XPCD TO BE PRESENT ON THU...BUT SOMEWHAT WKR THAN PREV
DAYS OWING TO WWD DEPARTURE OF RDG. VERY MODEST CNVGNC ALONG
INVERTED SFC TROF AND TERRAIN CIRCULATIONS WILL PROVIDE ONLY CLR
FOCI FOR ANY CNVCTV DVLPMT THU AFTN. ISOLD-SCT CVRG OF TSTMS WERE
INCLUDED ON THU...SUBSIDING THU EVE WITH LOSS OF HEATING.
BELT OF MDT WSWLY H5 FLOW SPREADS SWD ON FRI AS AGGRESSIVE TROF
DIGS INTO S-CNTRL CANADA AND NRN PLNS. PRIMARY FOCUS FOR TSTM
DVLPMT WILL BE ALONG ASSOCIATED CDFNT MAINLY NW OF FCST AREA. BUT
GIVEN INCRG LIFT AND QUALITY INSOLATION...TSTMS CANNOT BE RULED
OUT ON FRI. MDT-STG INSTBY MAY COMPENSATE FOR MODEST SHEAR AND
COULD PROMOTE A THREAT OF SVR TSTMS WITH DMGG WIND GUSTS ON FRI
AFTN.
MAXIMA XPCD TO BE CAPPED IN THE LWR 90S OWING TO VERY HIGH MSTR
CONTENT OF BNDRY LYR. THE COMBINATION OF LWR 90S TEMPS AND DEWPT
TEMPS IN THE LWR-MID 70S WILL YIELD HEAT INDICES IN THE UPR 90S-NR
100 BOTH WED AND THU. HEAT CONCERNS WILL BE HIGHLIGHTED IN HWO.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
SGFNT SVR EPISODE RMNS PSBL ON SAT AS VERY HUMID AMS WILL RMN IN
THE RGN IN ADVC OF ARRIVING CDFNT. H5 FLOW WILL INCR FRI NGT-SAT
AS SHRTWV TROF CROSSES GRTLKS RGN. CNVCTN XPCD TO DVLP RELATIVELY
EARLY ON SAT ALONG AND AHD OF ADVCG CDFNT.
STG INSTBY AND MDT BULK SHEAR WILL SUPPORT ORGANIZED UPDRAFTS.
SHEAR VECTOR WILL BE RELATIVELY PARALLEL TO ADVCG CDFNT...SO
CNVCTN XPCD TO BCM LINEAR RELATIVELY QUICKLY. OWING TO VERY HIGH
FRZG LVLS AND STEEP LAPSE RATES...DMGG WIND GUSTS WILL BE PRIMARY
SVR THREAT FROM THESE TSTMS.
CDFNT CROSSES RGN BY SAT EVE AND SCOURS OUT MSTR. PCPN WILL SHIFT
SE OF FCST AREA BY SUN AFTN. TEMPS WILL TREND TWD LWR 80S EARLY
NEXT WK IN WAKE OF CDFNT PASSAGE.
NELY UPSLP FLOW ON MON MAY SUPPORT A FEW SHWRS ALONG TERRAIN.
GUIDANCE SUGGESTS A SHRTWV TROF WILL STRENGTHEN SWLY LOW-LVL FLOW
BY TUE AND WILL PROMOTE INCRG CHCS FOR TSTMS AS BNDRY-LYR MSTR
INCRS.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
GENERAL VFR EXPECTED AT MOST TAF SITES OVERNIGHT. SHOWERS FROM LAST
EVE IN THE VICINITY OF KFKL AND KDUJ MAY PROVIDE ENOUGH LOW LEVEL
SATURATION FOR FOG TO DEVELOP...AS IS ALREADY THE CASE AT DUJ.
GENERALLY THINK THIS FOG WILL BE MVFR BUT THEY COULD OCCASIONALLY
DROP TO IFR. THINK THIS COULD ALSO BE THE CASE FOR ZZV...WITH
DEWPOINTS EXPECTED TO REMAIN ELEVATED THERE.
EXPECT DIURNAL CU TO DEVELOP ONCE AGAIN TUESDAY...BUT BE WIDER IN
COVERAGE WITH WESTWARD TRACKING HIGH. THIS COULD ALSO PROMOTE A BIT
MORE SHOWER/THUNDERSTORM DEVELOPMENT IN BOTH THE LAKE BREEZE AND
ALONG THE RIDGES. WITHOUT SOLID CONFIDENCE THAT ANY SITE WILL BE
IMPACTED...LEFT SHRA/TSRA MENTION OUT FOR NOW.
WINDS WILL REMAIN LIGHT AND VARIABLE.
.OUTLOOK.../TUESDAY NIGHT THROUGH SATURDAY/...
RESTRICTIONS IN MRNG FOG WILL BE PSBL EACH DAY. BEST CHC FOR MORE
WDSPRD RESTRICTIONS WILL BE SAT AS CDFNT PASSAGE INVIGORATES BROAD
CVRG OF TSTMS IN THE RGN.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
34/KRAMAR
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
332 AM EDT TUE JUL 16 2013
.SYNOPSIS...
HOT AND HUMID CONDITIONS ARE EXPECTED ALL WEEK WITH HIGH PRESSURE
OVERHEAD. A COLD FRONT DROPS SOUTH FROM CANADA INCREASING THE
CHANCE OF SHOWERS AND THUNDERSTORMS FRIDAY AND SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TEMPERATURES AND DEWPOINTS ACROSS THE FORECAST AREA ARE STRUGGLING
TO DROP EARLY THIS MORNING. THE HRRR AND THE LAMP SEEM TO BE
HANDLING THIS QUITE WELL...SO THEY WERE USED THROUGH THE DAY
TODAY. THIS BRINGS THE DEWPOINTS UP THROUGH THE AFTERNOON WHICH IN
TURN BRINGS APPARENT TEMPERATURES INTO THE MID TO UPPER 90`S OVER
MY EASTERN OH...SOUTHWESTERN PA...AND NORTHERN WV PANHANDLE
COUNTIES. THUS...AN SPS WILL BE ISSUED WITH THE MORNING PACKAGE
FOR HOT TEMPERATURES AS IT WILL BE JUST UNDER HEAT ADVISORY
CRITERIA.
THE MID LEVEL HIGH WILL CONTINUE TO SHIFT WESTWARD TODAY ALLOWING
FOR THE CAP TO WEAKEN THIS AFTERNOON. THIS COULD ALLOW FOR A BIT
MORE THUNDERSTORM COVERAGE THAN YESTERDAY...MAINLY ALONG THE LAKE
BREEZE BOUNDARY TO THE NORTH AND IN THE HIGHER ELEVATIONS.
HOWEVER...THE HI RES MODELS ARE SUGGESTING THAT A FEW
SHOWERS/THUNDERSTORMS COULD DEVELOP A BIT FURTHER SOUTH AND
WEST...SO A ISOLATED THUNDERSTORM MENTION WAS ADDED TO ALL OF THE
FORECAST AREA BY LATE AFTERNOON. CONFIDENCE IN THIS COVERAGE
REMAINS LOW HOWEVER...ESPECIALLY OVER EASTERN OHIO...SO FELT AN
ISOLATED MENTION WOULD SUFFICE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
HIGH PRES WILL CONTINUE TO SLOWLY MOVE WESTWARD THROUGH THE
PERIOD. CONTINUED A SLIGHT CHANCE MENTION FOR THUNDERSTORMS NORTH
AND ALONG THE RIDGES WEDNESDAY. APPARENT TEMPERATURES WILL ONCE
AGAIN GET VERY CLOSE TO 100 DEGREES WEDNESDAY AFTERNOON. FOR
NOW...WILL CONTINUE TO HIGHLIGHT HOT...HUMID WEATHER IN THE HWO.
BIAS CORRECTED MOS WAS USED FOR TEMPERATURES...WITH ABOVE SEASONAL
VALUES EXPECTED BOTH DAY AND NIGHT.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
INCRSG FLOW ALOFT WITH SEWD PROPAGATING HUDSON BAY LOW WL SPPRT INCRSG
TSTM POTENTIAL AS THE ASSOCIATED SFC FRONT...AND WEEKEND APPCH.
WITH THAT INCRSD FLOW WL COME SEVERE POTENTIAL WHICH HAS BEEN
MENTIONED IN THE HAZARDOUS WEATHER OUTLOOK FOR NOW.
THE FRONT IS PROJECTED ACROSS THE AREA BY SUNDAY WITH WANING PCPN
CHCS AND A COOLER/DRIER AIRMASS.
&&
.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
GENERAL VFR EXPECTED AT MOST TAF SITES OVERNIGHT. SHOWERS FROM LAST
EVE IN THE VICINITY OF KFKL AND KDUJ MAY PROVIDE FOR ENOUGH LOW
LEVEL SATURATION FOR FOG TO DEVELOP...AS IS ALREADY THE CASE AT DUJ.
GENERALLY THINK THIS FOG WILL BE MVFR BUT THEY COULD OCCASIONALLY
DROP TO IFR. THINK THIS COULD ALSO BE THE CASE FOR ZZV...WITH
DEWPOINTS EXPECTED TO REMAIN ELEVATED THERE.
EXPECT DIURNAL CU TO DEVELOP ONCE AGAIN TUESDAY...BUT BE WIDER IN
COVERAGE WITH WESTWARD TRACKING HIGH. THIS COULD ALSO PROMOTE A BIT
MORE SHOWER/THUNDERSTORM DEVELOPMENT IN BOTH THE LAKE BREEZE AND
ALONG THE RIDGES. WITHOUT SOLID CONFIDENCE THAT ANY SITE WILL BE
IMPACTED...LEFT SHRA/TSRA MENTION OUT FOR NOW.
WINDS WILL REMAIN LIGHT AND VARIABLE.
.OUTLOOK.../TUESDAY NIGHT THROUGH SATURDAY/...
RESTRICTIONS ARE POSSIBLE EACH MORNING WITH FOG. OTHERWISE...THE
BEST CHANCE FOR WIDESPREAD RESTRICTIONS WILL COME WITH INCREASED
PRECIPITATION CHANCES ON SATURDAY AS A COLD FRONT APPROACHES.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
420 AM EDT TUE JUL 16 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 419 AM EDT TUE JUL 16 2013
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW SPRAWLING UPR RDG
CENTERED OVER THE LOWER GRT LKS. ALTHOUGH THE 00Z GRB RAOB INDICATES
THE TROPOSPHERE OVER THE UPR GRT LKS HAS MOISTENED CONSIDERABLY OVER
THE LAST DAY OR SO WITH 00Z PWAT UP TO 1.82 INCHES /185 PERCENT OF
NORMAL/...MID LVL WARMTH WITH H5 TEMPS ARND -5C HAS MAINTAINED
RATHER UNIMPRESSIVE MID LVL LAPSE RATES IN THE ABSENCE OF ANY
DYNAMIC FORCING UNDER THE RDG. THE CONVECTIVE TEMP ON THE 00Z GRB
SDNG WAS 94. A FEW -SHRA DID POP UP OVER WI YDAY AFTN...BUT THESE
DISSIPATED LAST EVNG WITH THE LOSS OF DAYTIME HEATING. HOWEVER...
MORE ISOLD -SHRA HAVE DVLPD OVER NW WI/ADJOINING MN IN AREA WHERE
RUC ANALYSIS SHOWS KINX NEAR 36. PERSISTENT BAND OF MSTR THAT HAS
PLAGUED NE MN/NW LK SUP WITH CLDS/SOME SHRA THE LAST FEW DAYS HAS
DRIFTED TO THE N INTO ONTARIO. OTRW...SFC TEMPS ARE RUNNING WELL ABV
NORMAL EARLY THIS MRNG DESPITE CLR-PCLDY SKIES. TO THE NW...THERE IS
A STRONGER SHRTWV JUST W OF LK WINNIPEG MOVING ENEWD THRU SRN CANADA.
MAIN FCST CONCERNS IN THE SHORT TERM ARE TEMPS AND SHRA/TS CHCS AS
UPR RDG REMAINS DOMINANT OVER THE GRT LKS.
TODAY...CENTER OF UPR RDG/SFC HI PRES OVER THE LOWER GRT LKS IS FCST
TO DRIFT ONLY SLOWLY TO THE W...SO MID LVL WARM AIR WL REMAIN OVER
THE CWA. STRONGER SHRTWV/ACCOMPANYING DYNAMICS LIFTING ENEWD THRU
SCENTRL CANADA WL RIDE WELL TO THE N OF UPR MI AND NOT IMPACT THE
CWA. BUT WITH DAYTIME HEATING...BULK OF NUMERICAL MODELS GENERATE
SHRA/TS OVER UPR MI TODAY. THERE ARE A NUMBER OF NEGATIVES FOR
PCPN...THE ABSENCE OF ANY DYNAMIC FORCING...FCST ACYC H85 SW FLOW
THAT WL RESULT IN ONLY WEAK LK BREEZE DVLPMENT OFF LK SUP...AND VERY
HI CONVECTIVE TEMP SHOWN ON THE 00Z GRB RAOB. HOWEVER...WITH SOME
ISOLD -SHRA OVER NW WI...SUSPECT SOME SHRA/TS WL IMPACT UPR MI
MAINLY BY LATE MRNG AFTER ONSET OF DAYTIME HEATING. FCST DRYING IN
THE AFTN IN THE WAKE OF AREA OF HIER KINX NOW MOVING TOWARD THE CWA
MAY CAUSE THE SHRA TO DIMINISH DESPITE MOVING TOWARD PEAK HEATING
TIME. THE BEST CHC FOR MORE PERSISTENT SHRA/TS WL BE OVER THE
ECENTRL CWA ON THE EDGE OF THE LK BREEZE BNDRY MOVING ONSHORE FM LK
MI. WITH FCST H85 TEMPS ARND 19C...EXPECT ANOTHER WARM DAY WITH MAX
TEMPS WELL INTO THE 80S TO LO 90S OVER THE INTERIOR. HIER HUMIDITY
WL MAKE THE AIR FEEL QUITE UNCOMFORTABLE...WITH APPARENT TEMPS
RISING TO ARND 95 AT SOME PLACES.
TNGT...COLD FNT ATTENDANT TO DISTURBANCE MOVING THRU CANADA AND INTO
HUDSON BAY IS PROGGED TO DRIFT S INTO NRN LK SUP BY 12Z WED UNDER
MODEST H5 HGT FALLS. CURRENT FCST SHOWS OVERNGT POPS OVER NRN LK SUP
CLOSE TO THIS INCOMING BNDRY AND AREA OF HIER FCST MID LVL RH...SO
WL RESTRICT FCST POPS TO THIS AREA AND KEEP THE REST OF THE CWA DRY
CLOSER TO HI PRES/CORE OF WARMER MID LVL AIR. WITH FCST H925 WINDS
UP TO 25-30 KTS UNDER SHARPENING PRES GRADIENT TO THE S OF THIS
INCOMING FNT...OVERNGT LO TEMPS SHOULD BE FAIRLY WARM...ESPECIALLY
IN THE DOWNSLOPE AREAS NEAR LK SUP.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 419 AM EDT TUE JUL 16 2013
STARTING OUT THE LONG TERM AT 12Z WED...THE CWA WILL BE BETWEEN AN
UPPER HIGH CENTERED OVER IN AND A LOW PRESSURE SYSTEM OVER NRN
HUDSON BAY. STRETCHING FROM THE HUDSON BAY LOW WILL BE A
TROUGH/FRONT OVER QUEBEC SW TO THE NRN CWA. THE FRONT WILL NOT MOVE
MUCH THROUGH THU...WITH SLOW SOUTHERLY MOVEMENT OR NEARLY STATIONARY
BEHAVIOR EXPECTED. WIND FIELDS WILL BE NEAR UNIDIRECTIONAL AND FOR
THE MOST PART PARALLEL TO THE FRONT. WITH INSTABILITY ALONG AND S OF
THE FRONT...EXPECT CONVECTION FOR MUCH OF THE PERIOD. TROUBLE COMES
WITH POSSIBILITIES OF STRONG TO SEVERE STORMS AND FLOODING. WINDS
PARALLEL TO THE SLOW MOVING FRONT AND PWATS OF 1.5-2.0 INCHES
/150-200 PERCENT OF NORMAL/ COMBINED WITH INSTABILITY MAY MAKE FOR
SOME AREAS RECEIVING EXCESSIVE RAINFALL...BUT IT IS TOO DIFFICULT AT
THIS TIME FRAME TO TELL WHERE EXACTLY THAT WILL BE /MORE OF A
NOWCASTING ISSUE/. AS FOR STRONG-SEVERE POTENTIAL WED-THU...THE BEST
CHANCE FOR GOOD INSTABILITY LOOKS TO BE ON WED AS THE FRONT WILL BE
MOVING INTO UPPER MI...WHILE THU LOOKS MORE UNCERTAIN SINCE THE
POSITION OF THE FRONT AND CLOUD COVER ARE MORE IN QUESTION.
FOR THE SPECIFICS FOR WED...CAPE VALUES OF 1500-2500J/KG ARE
POSSIBLE AS SFC TEMPS WARM INTO THE 80S TO AROUND 90. 0-6KM BULK
SHEAR LOOKS TO BE AROUND 30KTS /AS PREVIOUSLY STATED...THAT IS
MOSTLY UNIDIRECTIONAL/. DCAPE VALUES LOOK TO BE AOB 1000J/KG THANKS
TO SOME DRY LAYERS IN THE SOUNDING...WHICH MAY HELP GET SOME STRONG
WINDS OUT OF STORMS. MAY SEE THUNDERSTORMS INITIATE IN THE
AFTERNOON...OR COULD EVEN SEE A CONVECTIVE COMPLEX MOVE ALONG THE
FRONT. WITH WEAK SFC WINDS...MAY SEE CONVECTION FOCUSING ON LAKE
FREEZES THAT FORM. CONVECTION MAY THEN CONTINUE INTO WED NIGHT...BUT
WOULD MORE LIKELY BE ELEVATED WITH STRONG/SEVERE POTENTIAL
CONTINUING DUE TO AN INCREASE IN THE NOCTURNAL LOW LEVEL JET...BUT
IT WOULD LIKELY DEPEND MORE ON THE PATH OF ANY CONVECTIVE COMPLEXES
THAT MAY FORM.
THU...AS SAID BEFORE...MORE UNCERTAINTY WITH CONVECTIVE CHANCES DUE
TO QUESTIONS ABOUT FRONTAL LOCATION AND CLOUD COVER. SHOULD BE LESS
DCAPE AS MORE MOISTURE WILL HAVE MOVED INTO THE AREA...SO OVERALL
THINK THE CHANCE OF STRONGER/SEVERE STORMS IS MORE LIMITED THAN WED.
SHOULD SEE CONVECTION CONTINUE INTO THU NIGHT AS HEIGHT FALLS MOVE
INTO THE REGION AS THE UPPER LOW DROPS TO SRN HUDSON BAY...WHICH
WILL BOOST FORCING ACROSS THE CWA WHILE THE FRONT REMAINS FAIRLY
STATIONARY. THREAT OF HEAVY RAIN/TRAINING STORMS CONTINUES...BUT THE
LOCATION IS AGAIN NEARLY IMPOSSIBLE TO PINPOINT AT THIS TIME. SFC
TEMPS SHOULD BE COOLER IN THE 70S TO MID 80S.
FRI-SAT...THE UPPER LOW WILL WEAKEN WHILE MOVING TO JAMES BAY BY 12Z
SAT...THEN TO NRN QUEBEC BY 00Z SUN. THIS WILL ALLOW A MORE
SIGNIFICANT UPPER TROUGH TO SWING ACROSS THE CWA FRI INTO
SAT...WHICH WILL PUSH THE COLD FRONT WELL S OF THE CWA BY FRI NIGHT.
MAY STILL SEE SOME SHOWERS ON FRI AFTERNOON AS THE TROUGH PUSHES
IN...BUT TEMPS WILL BE COOLER WITH HIGHS IN THE 70S TO LOW 80S IN
MOST LOCATIONS. ALTHOUGH THE UPPER TROUGH IS STILL MOVE THROUGH
SAT...SFC HIGH PRESSURE AND ASSOCIATED DRY AIR OVER THE CWA SHOULD
KEEP THINGS DRY FOR THE MOST PART. HIGHS SAT LOOK TO BE IN THE 60S
AND 70S.
THERE IS THE POSSIBILITY OF ANOTHER TROUGH MOVING THROUGH ON SUN AND
MON /BEST CHANCES ON MON/...WHICH WOULD LEAD TO PRECIP ACROSS MUCH
OF THE CWA. HOWEVER...CONFIDENCE ON THE POSITION/TIMING/EXTENT OF
THE TROUGH IS LOW AT THIS POINT...SO WILL JUST CONTINUE TO LOAD A
CONSENSUS OF MODELS INTO FORECAST FOR THIS TIME PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 122 AM EDT TUE JUL 16 2013
WITH HIGH PRESSURE IN PLACE OVER UPPER MICHIGAN...EXPECT VFR
CONDITIONS THROUGH MOST OF THE TAF PERIOD. THE ONLY CONCERN WILL BE
THE POTENTIAL FOR FOG DEVELOPMENT EARLY THIS MORNING. THOUGH DEW
POINTS ARE MOIST (IN THE LOWER 60S) AND SKIES CLEAR...FOG MAY BE
LIMITED SOMEWHAT DUE TO DEVELOPING SOUTHERLY BOUNDARY LAYER WINDS TO
15-20 KT. WILL INCLUDE MVFR VSBYS FOR ALL TAF SITES FM 09-12Z BUT
MIXING FM STRONGER BOUNDARY LAYER WINDS SHOULD ALLOW IMPROVEMENT
AROUND SUNRISE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 419 AM EDT TUE JUL 16 2013
WITH WEAK PRES GRADIENT AND HI STABILITY OVER THE RELATIVELY CHILLY
LAKE WATERS...EXPECT LIGHT WINDS UNDER 20 KTS THRU TONIGHT. THE
PERSISTENCE OF A FAIRLY HUMID AIRMASS OVER THE LAKE WILL RESULT IN
PATCHY FOG. A LOW PRESSURE SYSTEM AND FRONTAL BOUNDARY WILL EFFECT
THE REGION WEDNESDAY THROUGH FRIDAY...HOWEVER...WINDS SHOULD REMAIN
LIGHT AND GENERALLY LESS THAN 15 KNOTS. HIGH PRESSURE BUILDS IN FOR
MUCH OF THE WEEKEND ALLOWING WINDS TO REMAIN LIGHT AND VARIABLE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...VOSS
MARINE...KC/TITUS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1150 PM CDT MON JUL 15 2013
.UPDATE...
ISSUED AT 1147 PM CDT MON JUL 15 2013
LINE OF WEAKENING COVNECTION MOVING INTO BOTTINEAU AND APPROACHING
TOWNER TO NORTHWEST OF GARRISION. HRRR STILL HAS ACTIVITY MOVING
EAST INTO DVL BASIN 06Z-09Z PERIOD AND WEAKLY INTO NRN VALLEY
PERHAPS AFTER THAT BEFORE DYING OFF. DID TWEEK POPS BASED ON THIS.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 304 PM CDT MON JUL 15 2013
CONVECTION CHANCES WILL BE THE MAIN CHALLENGE THROUGHOUT THE
PERIOD.
THE UPPER RIDGE OVER THE EASTERN CONUS CONTINUES TO BUILD INTO THE
CENTRAL PART OF THE CONUS...WITH A SHORTWAVE TROUGH OVER SASK THAT
SHOULD MOVE THROUGH SOUTHERN CANADA TONIGHT. RAIN SHOWERS HAVE
CONTINUED IN A BAND ALONG AN OLD FRONTAL BOUNDARY FROM THE
SOUTHWESTERN CWA TO FARGO AND PARK RAPIDS. SHORT RANGE MODELS ALL
HAVE THIS BAND OF RAIN SLOWLY LIFTING NORTH FOR THE REST OF THE
AFTERNOON BEFORE DISSIPATING THIS EVENING AS THE FRONT WASHES OUT.
WITH INSTABILITY LIMITED BY THE CLOUDS AND RAIN FOR MUCH OF THE
DAY...SHOWERS WITH ONLY AN ISOLATED THUNDER MENTION SEEM
REASONABLE. THE NEXT CHANCE FOR PRECIP WILL ARRIVE IN OUR
NORTHWESTERN CWA LATER TONIGHT AS THE SHORTWAVE OVER CANADA MOVES
EAST AND HELPS PUSH A TROUGH AXIS INTO CENTRAL ND. THINK THAT MOST
ACTIVITY WILL BE OVER THE WESTERN PART OF THE STATE BUT SOME COULD
HOLD TOGETHER LONG ENOUGH TO IMPACT THE DEVILS LAKE BASIN SO KEPT
AROUND 30 POPS THERE.
THE UPPER RIDGE WILL CONTINUE TO BUILD WESTWARD THROUGH
TOMORROW...WITH THE MAIN WESTERLIES LIFTING JUST TO OUR NORTH.
MODELS ARE ALL IN PRETTY DECENT AGREEMENT ON DROPPING A WEAK COLD
FRONT INTO THE CWA AND STALLING IT OUT...ALTHOUGH THERE ARE
DIFFERENCES IN EXACTLY WHERE IT SETS UP. MOST SEEM TO STALL THE
BOUNDARY OVER THE NORTHERN TO CENTRAL CWA...AND WITH MOISTURE AND
INSTABILITY POOLING ON THE NORTH SIDE OF THE BOUNDARY...IT COULD
BE A FOCUS FOR CONVECTION TUESDAY AFTERNOON AND EVENING. DEEP
LAYER SHEAR IS NOT HUGELY IMPRESSIVE SO ANY SEVERE WILL BE
ISOLATED AT BEST. THE FRONT WILL CONTINUE TO WOBBLE OVER THE AREA
THROUGH TUESDAY NIGHT...SO CONTINUED TO KEEP POPS GOING FOR OUR
NORTHERN COUNTIES.
AS FOR TEMPERATURES...MUCH WILL DEPEND ON EXACTLY HOW CLOUDS AND
PRECIP PLAY OUT. FOR NOW KEPT LOWS MAINLY IN THE 60S AND HIGHS IN
THE UPPER 70S TO 80S...WITH HIGHEST VALUES IN THE SOUTHERN CWA
AND COOLEST IN THE NORTH WHERE THE FRONTAL BOUNDARY AS WELL AS
CLOUDS ARE MOST LIKELY TO BE FOUND.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 304 PM CDT MON JUL 15 2013
WEDNESDAY...THE MODELS SHOW SOME INDICATION OF THE FRONT SAGGING
SOUTH A LITTLE BIT. CONTINUED TO KEEP SCATTERED POPS GOING A BIT
FURTHER SOUTH THAN TUESDAY. THINK A MORE SIGNIFICANT CHANCE FOR
CONVECTION WILL ARRIVE ON THURSDAY AS 500MB HEIGHTS BEGIN TO FALL
ACROSS THE AREA AS A SHORTWAVE TROUGH DIGS INTO SOUTHERN CANADA.
THE SFC FRONT WILL LIFT BACK NORTH A BIT...AND THEN DROP SOUTH AS
A COLD FRONT BY LATE THURSDAY. WITH THE MAIN WESTERLIES BACK OVER
THE AREA...DEEP LAYER SHEAR WILL BE AROUND 40-50 KTS AND MODELS
SHOW SOME STRONG INSTABILITY NEAR THE BOUNDARY. KEPT CHANCES FOR
THUNDERSTORMS HIGH FOR THURSDAY.
FOR THURSDAY NIGHT THROUGH MONDAY THE REGION WILL ESSENTIALLY
REMAIN IN NORTHWEST FLOW ALOFT. LOOKS LIKE THERE COULD BE SUBTLE
WAVES IN THE FLOW WHICH COULD HELP INITIATE SOME LOW END
CONVECTIVE CHANCES THU THROUGH SUN. BETTER CHANCES FOR PCPN MAY
COME WITH A STRONGER WAVE AND FRONT SOMETIME ON MONDAY ALTHOUGH
MODELS ARE NOT IN VERY GOOD AGREEMENT BY THEN. SHOULD BE A
NORTHEAST TO SOUTHWEST TEMP GRADIENT WITH THE NORTHWEST FLOW UNTIL
SUNDAY WHEN TEMPS RISE AHEAD OF THE NEXT WAVE AND FRONT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1147 PM CDT MON JUL 15 2013
BEMIDJI AREA IS IN QUESTION OVERNIGHT INTO TUES AM DUE TO POSSIBLE
AREAS OF FOG AND LOW CLOUDS. OTHERWISE MUCH OF THE STRATOCU DECK
HAS BROKEN UP LEAVING PATCHY CLOUD COVER. DO EXPECT SOME MID LEVEL
CLOUD AND HIGH CLOUD TO MOVE IN FROM THE WEST WITH TSTM AREA
ACROSS THE NE ND/FAR NW MN LATER TONIGHT INTO TUESDAY. KEPT TEMPO
FOR TSRA AT DVL AIRPORT FOR 07Z-09Z PERIOD...BUT NOT IN GFK DUE TO
LESS CHANCE OF IT MAKING IT THIS FAR EAST. FRONTAL WIND SHIFT
SHOULD REACH DVL MIDDAY AND GFK-TVF BY LATE AFTN.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...RIDDLE
SHORT TERM...JR
LONG TERM...JR/GODON
AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1130 PM CDT MON JUL 15 2013
.DISCUSSION...
SEE 06Z AVIATION DISCUSSION.
&&
.AVIATION...
HIGH MOISTURE LEVELS WILL PERSIST FOR THE DURATION OF THE TAF
PACKAGE. HRR AND RAP BOTH SHOW SOME DECREASE IN COVERAGE FROM
06-09Z WITH SHRA RAPIDLY INCREASING IN COVERAGE AGAIN AROUND 10Z
NEAR THE COAST DUE TO STRONG SPEED CONVERGENCE. LOW CONVECTIVE
TEMPS IN THE MID 80S SHOULD ALLOW POP-UP SHOWERS THROUGH THE DAY
TUESDAY. CAN`T REALLY PINPOINT WHEN AND WHERE SHRA WILL DEVELOP
SO WILL CARRY VCSH AND TEMPO WHEN PRECIP APPROACHES AREA AIRPORTS.
WINDS WILL BRIEFLY GUST ABOVE 15 KTS AS THE SHOWERS MOVE THROUGH.
WINDS WILL ALSO BACK FROM THE SE TO THE EAST ON TUES MORNING. 43
&&
.PREV DISCUSSION... /ISSUED 850 PM CDT MON JUL 15 2013/
DISCUSSION...
SCT SHOWERS AND ISO TSTMS CONTINUE MOVING W/NW ACROSS SE TX THIS
EVENING IN A MOIST AND AN UNSTABLE ATMOSPHERE. BELIEVE SCT
CONVECTION WILL CONTINUE THROUGH THE NIGHT WITH SE AREAS BECOMING
MORE ACTIVE DURING THE EARLY MORNING HOURS THAN THE FAR INLAND
AREAS. NO BIG CHGS TO THE FORECAST...JUST SOME SMALL ADJUSTMENTS
TO EVE POPS AND CLOUD COVER. 33
MARINE...
WILL BE ADDING A CAUTION STATEMENT TO THE OFFSHORE ZONES FOR 15
TO 20 KTS WINDS.
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 72 90 73 91 73 / 30 60 40 50 20
HOUSTON (IAH) 74 90 74 90 75 / 40 60 40 50 20
GALVESTON (GLS) 81 88 80 88 81 / 50 60 40 50 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 5 AM CDT TUESDAY FOR
THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA
SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT OUT 20 NM.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1152 PM CDT MON JUL 15 2013
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 249 PM CDT MON JUL 15 2013
CURRENTLY AS OF 19Z...
WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED TROUGHING OVER
SOUTHWEST CANADA...AN UPPER LOW OVER THE TEXAS PANHANDLE
RETROGRADING WESTWARD...AND A NEAR 600 DAM HIGH NEAR TOLEDO OHIO
ALSO RETROGRADING WESTWARD. STANDARD DEVIATIONS AGAIN WITH THIS HIGH
ARE RUNNING 2.5 ABOVE NORMAL. BETWEEN THE UPPER LOW AND SUBTROPICAL
HIGH...DEEP LAYER SOUTH TO SOUTHEAST WINDS ARE ADVECTING HIGHER
PRECIPITABLE WATER VALUES TOWARDS THE FORECAST AREA. 12Z DVN AND ILX
REPORTED VALUES OF 1.89 AND 2.04 INCHES RESPECTIVELY. HIGHER SURFACE
DEWPOINTS IN THE LOW 70S HAVE ACCOMPANIED THIS DEEP MOISTURE. WITH
TEMPERATURES THAT HAVE CLIMBED INTO THE UPPER 80S/LOW 90S...
RESULTING IN MLCAPE VALUES OF 500-1000 J/KG...ISOLATED SHOWERS HAVE
FORMED. NO LIGHTNING YET...WHICH MAY BE A RESULT OF THE SHALLOW
NATURE OF THE SHOWERS AND DEEP WARM CLOUD DEPTHS PREVENTING ICE
PRODUCTION. DESPITE THE HIGH 500MB HEIGHTS OVER THE FORECAST
AREA...ON THE ORDER OF 594-597 DAM...850MB TEMPS ARE ONLY 16-17C.
THE REASON THESE ARE COOL COMPARED TO THE 500MB HEIGHT IS A RESULT
OF THE SUBTROPICAL HIGH BEING OF ATLANTIC OCEAN ORIGIN. HAD IT COME
OUT OF THE WESTERN U.S....THE 850MB TEMPS WOULD BE A LOT HIGHER.
SYNOPTIC OVERVIEW...
MODELS CONTINUE TO SHOW THE STRONG SUBTROPICAL HIGH DRIFTING
WESTWARD THROUGH TUESDAY...REACHING NEAR GARY INDIANA BY 00Z
WEDNESDAY. THUS...500MB HEIGHTS WILL CONTINUE TO RISE OVER THE
FORECAST AREA...IMPLYING INCREASING MID-LEVEL SUBSIDENCE.
FOR TONIGHT...
ANY AFTERNOON CONVECTION THAT IS SPREADING NORTHWARD...ACCOMPANYING
THE HIGHER PRECIPITABLE WATER...WILL DIMINISH BY 03Z THIS EVENING
WITH LOSS OF HEATING SINCE IT IS HIGHLY DIURNALLY DRIVEN. THE REST
OF THE NIGHT LOOKS DRY WITH ANY FORCING FOR NOCTURNAL CONVECTION
WELL NORTH OF THE FORECAST AREA.
ON TUESDAY...
THE BATTLE CONTINUES OF WHETHER OR NOT TO NEED A MENTION OF SHOWERS
AND THUNDERSTORMS IN THE AFTERNOON. MODELS WERE A LITTLE HYPERACTIVE
WITH DIURNAL CONVECTION TODAY...ESPECIALLY THE 15.12Z NAM SHOWING
PRECIP ACROSS ALL OF ILLINOIS BY 15Z AND THERE WAS NONE IN REALITY.
ALL MODELS ARE IN AGREEMENT OF MUCH LESS QPF...AND THE 15.12Z NAM
CONTINUES TO SHOW A DRY FORECAST FOR THE FORECAST AREA. THERE ARE
OTHER NEGATIVES TOO FOR CONVECTION...BEING CLOSER TO THE SUBTROPICAL
HIGH...AND 0.25-0.5 INCH DRYING OF PRECIPITABLE WATER VALUES
ORIGINATING FROM EASTERN KY/TN THIS MORNING. SEEING THE DRY FORECAST
FROM THE NAM...THE 15.12Z CANADIAN WHICH DID A GOOD JOB WITH PRECIP
TODAY AND IS DRY FOR TUESDAY...ALONG WITH OTHER MODELS SHOWING VERY
LITTLE IF ANY QPF...WENT BACK TO A DRY FORECAST. 850MB TEMPS ARE 2C
HIGHER TOMORROW...BETWEEN 18-19C...SO WE SHOULD SEE ABOUT A SIMILAR
INCREASE IN HIGH TEMPERATURES INTO UPPER 80S/LOW 90S. DEWPOINTS UP
IN THE UPPER 60S/LOW 70S AND THE FORECAST HIGH TEMPERATURES WILL
LIKELY LEAD TO PLENTY OF CUMULUS...BUT MORE IMPORTANTLY MAKE IT FEEL
MUGGY. HEAT INDICES ARE STILL FORECAST TO TOP OUT IN THE 95-100
RANGE.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 249 PM CDT MON JUL 15 2013
SYNOPTIC OVERVIEW...
MODELS REMAIN CONSISTENT IN THE STRONG SUBTROPICAL HIGH RETROGRADING
ACTUALLY SOUTHWESTWARD THROUGH THE REST OF THE WEEK. THIS IS IN
RESPONSE TO FIRST THE TROUGH IN SOUTHWEST CANADA MARCHING
EAST-NORTHEAST AND FLATTENING THE RIDGE...AND FINALLY AN UPPER LOW
CURRENTLY OFF THE COAST OF SAN FRANSISCO DROPPING SOUTHEAST THROUGH
THE FORECAST AREA AS A SHORTWAVE TROUGH. BY SATURDAY WE SHOULD BE
LOOKING AT TROUGHING OVER THE WESTERN GREAT LAKES VERSUS THE CURRENT
RIDGING. HEADING INTO SUNDAY AND MONDAY...INDICATIONS ARE THAT A
MORE POTENT SHORTWAVE TROUGH WILL BE APPROACHING THE AREA IN THE
NORTHWEST FLOW.
HAZARDS...
HEAT INDICES REMAIN THE BIG CONCERN. TUESDAY THROUGH THURSDAY LOOK
SOLID TO HAVE AFTERNOON HEAT INDICES BETWEEN 95-100...ESPECIALLY IN
THE VALLEYS. HEAT ADVISORY CRITERIA REQUIRES 100 OR GREATER FOR 1
DAY OR GREATER THAN 95 FOR 4 OR MORE DAYS. THE MORE LIKELY OF THE
TWO OPTIONS TO HIT WOULD BE DURATION. HEAT INDICES ONLY TOPPED OUT
IN THE UPPER 80S TO MID 90S TODAY...SO THAT MEANS FRIDAY WOULD NEED
95 OR GREATER. WITH CONCERN OF THE FRONT AND CONVECTION COMING
THROUGH FRIDAY...HAVE REFRAINED AT THIS TIME FROM ISSUING A HEAT
ADVISORY. HOWEVER...WE WILL ISSUE A SPECIAL WEATHER STATEMENT TO
DISCUSS THE HEAT. NOTE THAT THIS TIME PERIOD OF 15TH THROUGH 18TH
OF JULY IS COMMONLY THE TIME TO GET HEAT.
THERE IS A POSSIBILITY OF SEVERE WEATHER TOO IN THE THURSDAY THROUGH
FRIDAY TIME PERIOD. THURSDAY/THURSDAY NIGHT WOULD BE MORE TO THE
NORTH...PERHAPS JUST TAYLOR/CLARK COUNTIES AS ALSO SHOWN IN THE SPC
DAY 4-8 OUTLOOK. FRIDAY IT ALL DEPENDS ON THE FRONTAL TIMING.
ADDITIONALLY...THE BEST 0-6KM SHEAR IS BEHIND THE FRONT...WITH ONLY
30-35 KT ON THE FRONT. SO IT WOULD SEEM THAT OVERALL ANY SEVERE
WEATHER WOULD BE ISOLATED WITH DAMAGING WINDS AND HEAVY RAIN THE
MAIN HAZARDS.
DAILY DETAILS...
TUESDAY NIGHT AND WEDNESDAY...
A COLD FRONT ACCOMPANYING THE SOUTHWEST CANADA TROUGH IS PROGGED TO
DROP INTO NORTHERN MN BY 12Z WED AND THEN LAY UP BETWEEN ST CLOUD MN
AND UPPER MI LATE WEDNESDAY. ENVISIONING CONVECTION ON THIS
BOUNDARY...DUE TO PLENTIFUL MOISTURE AND INSTABILITY AROUND IT...
ALONG WITH LAKE BREEZE ENHANCED CONVERGENCE. GIVEN ITS LOCATION...
ANTICIPATING ANY CONVECTION TO STAY UP TO THE NORTH THROUGH
WEDNESDAY. WILL NEED TO MONITOR TAYLOR COUNTY FOR A NEED FOR SOME
CHANCES OF PRECIPITATION IN LATER FORECASTS SHOULD THE BOUNDARY DROP
FARTHER SOUTH. OTHERWISE...PRECIPITABLE WATER VALUES ARE PROGGED TO
HOLD STEADY OR EVEN FALL A LITTLE MORE COMPARED TO TUESDAY...SO NOT
ANTICIPATING ANY DIURNAL CONVECTION. WITH CONTINUED AIRMASS
MODIFICATION OF THE SUBTROPICAL HIGH...850MB TEMPS CLIMB ABOUT
ANOTHER 1C...WHICH WITH PLENTY OF SUN SHOULD YIELD ANOTHER DAY OF
HIGHS IN THE UPPER 80S/LOW 90S.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...
THIS PERIOD APPEARS A BIT MORE MUDDLED / LESS CONFIDENCE / THAN
BEFORE. WITH A ZONAL UPPER FLOW PATTERN THROUGH THURSDAY...THE COLD
FRONT SITUATED UP TO OUR NORTH APPEARS LIKELY TO STAY IN PLACE. IN
FACT...ON THURSDAY NIGHT WHEN THE SHORTWAVE TROUGH DROPS INTO THE
DAKOTAS...THE FRONT COULD EVEN GET PROPELLED NORTHWARD. 15.12Z
ECMWF/GFS/NAM/UKMET/CANADIAN ALL DEPICT THE NOSE/GRADIENT OF THE
850MB MOISTURE TRANSPORT STAYING FOCUSED FROM NORTHERN MN INTO
NORTHERN WI/UPPER MI AND LOWER MI FROM WEDNESDAY NIGHT THROUGH
THURSDAY NIGHT. FIGURE CONVECTION WOULD EITHER BE TIED TO THE FRONT
OR NOSE OF THE MOISTURE TRANSPORT...WHICH BOTH SUGGEST NORTH OF THE
FORECAST AREA. CORFIDI VECTORS ARE FAIRLY LIGHT TOO IN TERMS OF
SPEEDS WITH DIRECTIONS MAINLY WEST OR WEST-NORTHWEST...SO IF AN MCS
FORMS IT COULD END UP STAYING NORTH OF THE AREA AS WELL. GIVEN ALL
OF THIS...HAVE DECIDED TO SHIFT ALL OF THE PRECIPITATION CHANCES
NORTHWARD...WHICH MEANS A REDUCTION ACROSS THE BOARD. WOULD NOT BE
SURPRISED IF ALL STORMS DURING THIS PERIOD STAY NORTH OF HIGHWAY 29.
TEMPERATURES THURSDAY LOOK SIMILAR TO TUESDAY AND WEDNESDAY WITH
850MB TEMPS OF 18-20C.
FRIDAY THROUGH MONDAY...
GOOD AGREEMENT REMAINS ABOUT THE COLD FRONT COMING THROUGH THE AREA
ON FRIDAY...AHEAD OF THE SHORTWAVE TROUGH. HAVE SOME CONCERN THAT
THIS FRONT COULD COME THROUGH DRY SEEING THE 15.00Z ECMWF. THREE
NEGATIVES WITH THIS FRONT FOR CONVECTION IS THE POSITIVELY TITLED
NATURE OF THE SHORTWAVE...WEAK CONVERGENCE AND THAT THE TIMING MAY
BE MESSED UP. FOR NOW LEFT A MODEL CONSENSUS 20-40 PERCENT CHANCES
IN THE FORECAST INTO FRIDAY EVENING. HIGH PRESSURE IS STILL
INDICATED TO BUILD INTO THE AREA FOR THE WEEKEND. HOWEVER...BEING
UNDER UPPER TROUGHING YIELDS CONCERNS FOR SHORTWAVES COMING THROUGH
AT PEAK HEATING AND INITIATING CONVECTION. THE 15.00Z ECMWF HINTED
AT THIS FOR SATURDAY...BUT THE 15.12Z RUN IS NOW DRY. WITH A DRY GFS
FORECAST...HAVE KEPT SATURDAY INTO SATURDAY NIGHT DRY. MUCH OF
SUNDAY MAY BE DRY TOO...THOUGH THERE ARE INDICATIONS FROM THE 15.12Z
ECMWF OF A SHORTWAVE MOVING INTO MN BRINGING CONVECTION TO LOCATIONS
MAINLY WEST OF THE MS RIVER. THUS...HAD TO KEEP SOME LOW CHANCES
THERE. ADDITIONAL CHANCES IN THE 20-40 RANGE ARE FORECAST INTO
MONDAY ASSOCIATED WITH THE MORE POTENT SHORTWAVE. TIMING IS STILL
YET TO BE DETERMINED ON THIS SHORTWAVE.
&&
.AVIATION...THROUGH 06Z WEDNESDAY
1152 PM CDT MON JUL 15 2013
AREA DIRECTLY UNDER HIGH PRESSURE WITH WEAK FLOW. EXPECTING A FEW
MID CLOUDS THROUGH THE NIGHT...AND WITH AMPLE LOW LEVEL MOISTURE
AND WEAK FLOW ANTICIPATING SOME LIGHT MIST/FOG FOR A FEW SPOTS.
PERHAPS A LITTLE BETTER CHANCE FOR A VISIBILITY RESTRICTION
TONIGHT AT KRST DUE TO THE QUARTER-INCH OF RAIN THEY PICKED UP
RIGHT AROUND SUNSET. STILL ONLY MVFR ANTICIPATED...WHICH SHOULD
QUICKLY DISSIPATE AFTER SUNRISE. VFR CONDITIONS WILL PREVAIL
THROUGH THE DAY TUESDAY. REALLY NOT MUCH SUPPORT FOR ANYTHING MORE
THAN SOME CUMULUS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...MW
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
1137 AM EDT TUE JUL 16 2013
.UPDATE...
MAIN CHANGE FOR THE UPDATE WAS TO REDUCE POPS INITIALLY. HRRR IS
SUGGESTING EXTENSIVE DEVELOPMENT ACROSS THE MOUNTAINS THIS
AFTERNOON. NAM/SREF/GFS ARE PICKING UP ON SOME ACTIVITY UP THERE
AFTER 18Z. WILL BE WATCHING THIS AREA FOR THE POTENTIAL NEED TO
INCREASE POPS ACROSS THE MOUNTAINS INTO THE AFTERNOON. HAVE CHANCE
POPS ACROSS THE SOUTHERN THIRD OF THE CWA...BUT SHOULD SEE BETTER
COVERAGE REMAIN SOUTH AND EAST OF THE AREA.
11
&&
.PREV DISCUSSION...
SHORT TERM /TODAY THROUGH WEDNESDAY/...
UPPER RIDGE REMAINS ANCHORED OVER THE OHIO VALLEY/GREAT LAKES AREA
TODAY INTO WEDNESDAY. EASTERLY FLOW WILL DOMINATE THROUGH MOST
LEVELS OF THE ATMOSPHERE THROUGH THE SHORT TERM. FORECAST SOUNDINGS
SHOWING PRECIPITABLE WATER DECREASING SOME TODAY. POPS IN THE 20 TO
30 PERCENT RANGE LOOK REASONABLE ACROSS THE CWA...FAVORING THE
AFTERNOON AND DIMINISHING AROUND 04Z. FOR WEDNESDAY...BOTH GFS AND
NAM INDICATE A WEAK SHORT WAVE MOVING WESTERLY AROUND THE EDGE OF
THE RIDGE FROM THE CAROLINAS INTO GA. ALSO...PW VALUES ARE ON THE
INCREASE BY THEN. BASED ON THIS HAVE PUSHED POPS UP A BIT ON
WEDNESDAY...STILL MOSTLY DIURNAL. MAX TEMPERATURES SHOULD RANGE IN
THE MID 80S TO LOW 90S NEXT COUPLE OF DAYS.
41
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
HIGH PRESSURE ALOFT WILL BE OVER THE OH-MID MS VALLEYS TO START THE
LONG TERM AND IS FORECAST TO WEAKEN THURSDAY. A MOIST AIRMASS WILL
STILL BE IN PLACE AND WITH ANY INSTABILITY WILL LEAD TO ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS. MODELS HINTING THAT AN UPPER
LEVEL DISTURBANCE COULD AFFECT THE AREA THURSDAY AND THIS IS MAKING
TIMING OF ANY CONVECTION DIFFICULT AS CONVECTION COULD OCCUR EARLIER
ON THURSDAY THAN THE MORE NORMAL DIURNAL TENDENCY.
UPPER HIGH CONTINUES TO WEAKEN ON FRIDAY WITH PLENTY OF MOISTURE AND
AFTERNOON/EVENING INSTABILITY IN PLACE. A TRANSITION TO WESTERLY FLOW
OCCURS STARTING SATURDAY AND THIS EVENTUALLY DEVELOPS INTO A TROUGH
ALOFT INTO TUESDAY WITH POTENTIAL FOR SHORT WAVE ENHANCEMENT OF ANY
CONVECTION. PLENTY OF MOISTURE WILL CONTINUE TO BE AVAILABLE ALONG
WITH MAINLY DIURNAL INSTABILITY. THIS WILL LEAD TO AT LEAST
SCATTERED SHOWERS AND THUNDERSTORMS THROUGH THE PERIOD INTO TUESDAY.
TEMPERATURES SHOULD GENERALLY BE CLOSE TO NORMAL WITH THE HIGHS
SLIGHTLY BELOW NORMAL FROM ABOUT SATURDAY ON.
BDL
AVIATION...
12Z UPDATE...
/ISSUED 742 AM EDT TUE JUL 16 2013/
EASTERLY WINDS SUPPORTING LIFR/IFR STRATUS AND FOG THIS MORNING OVER
MOST TAF SITES. IMPROVING TO MVFR AROUND 15Z THEN TO VFR BY 17Z.
WIDELY SCATTERED CONVECTION POSSIBLE MAINLY AFTERNOON INTO THE
EVENING BUT HAVE LEFT THUNDER OUT OF TAFS FOR NOW SINCE POPS ARE
ONLY 20 TO 30 PERCENT. EASTERLY WINDS PREVAILING TODAY AT 8 TO 10KT
OCCASIONALLY 15KT AT ATLANTA.
//ATL CONFIDENCE...12Z UPDATE...
MEDIUM CONFIDENCE FOR IMPROVEMENT OF CEILINGS. HIGH CONFIDENCE
REMAINING ELEMENTS.
41
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 91 71 91 71 / 20 20 40 30
ATLANTA 87 73 91 72 / 20 20 40 20
BLAIRSVILLE 89 67 87 67 / 20 20 40 30
CARTERSVILLE 90 70 91 68 / 20 20 40 20
COLUMBUS 91 73 92 73 / 30 20 30 20
GAINESVILLE 89 72 91 72 / 20 20 40 30
MACON 91 70 92 70 / 30 20 30 20
ROME 91 70 92 69 / 20 20 40 20
PEACHTREE CITY 89 70 91 69 / 20 20 40 20
VIDALIA 91 73 91 72 / 30 30 20 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...11
LONG TERM....01
AVIATION...11
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
939 AM CDT TUE JUL 16 2013
.DISCUSSION...
939 AM CDT
GOING FORECAST LOOKS TO BE IN GOOD SHAPE WITH NO BIG CHANGES
PLANNED AT THIS TIME...JUST A SLIGHT UPWARD ADJUSTMENT TO POPS.
MORNING SOUNDINGS AGAIN TODAY WERE VERY MOIST IN THE LOW LEVELS
THOUGH SLIGHTLY DRIER ABOVE 700MB AS COMPARED WITH YESTERDAY. PWATS
ARE DOWN ABOUT A QUARTER TO A HALF INCH OR FROM YESTERDAY`S LEVELS
BUT REMAIN 150% OR MORE OF AVERAGE. STRONG UPPER RIDGE HAS SHIFTED
WEST A BIT FROM YESTERDAYS POSITION WITH 500MB HEIGHTS 20-30 METERS
HIGHER THAN YESTERDAY. MID LEVEL TEMPS REMAIN VERY WARM WITH WEAK
MID LEVEL LAPSE RATES...HOWEVER ILX/DVN MORNING RAOBS AND ACARS OUT
OF MDW THIS MORNING SHOW NO INVERSION OR POTENTIAL CAPPING LAYER. SO
WHILE WE DONT HAVE ANY SHORTWAVE ALOFT TO PROVIDE FORCING LIKE
YESTERDAY AND WHILE PWATS ARE DOWN A BIT...STILL THINK ISOLATED
CONVECTION IS A DECENT BET TODAY. BOTH THE RUC FORECAST SOUNDINGS
AND MODIFIED OBSERVED SOUNDINGS SUGGEST MLCAPE VALUES REACHING
3000-3500 J/KG WITH LITTLE/NO INHIBITION.
AS MENTIONED THERE IS NO FORCING ALOFT TODAY AS WE SIT PARKED ALMOST
DIRECTLY UNDER THE UPPER RIDGE...HOWEVER VWP SHOWS SOUTHWEST WINDS
OFF THE DECK DIMINISHING FROM THE NOCTURNAL MAXIMA AND THINK WE
SHOULD ONCE AGAIN SEE A LAKE BREEZE FORM THIS AFTERNOON. GIVEN THE
LOW LFC`S THE SHALLOW FORCING ALONG THE LAKE BREEZE WITH NO CAP
SHOULD ONCE AGAIN BE ENOUGH TO KICK OFF ISOLATED TO WIDELY SCATTERED
AFTERNOON THUNDERSTORMS. ALREADY SEEING VERY HEALTHY CUMULUS FIELD
BLOSSOMING NEAR THE CONVERGENCE ZONE DOWNTOWN...SO GIVEN THE SET UP
AM PLANNING TO BUMP UP POPS SOME TODAY OVER LAKE AND COOK COUNTIES
IN ILLINOIS LATE THIS MORNING INTO THE AFTERNOON. THE SLIGHTLY DRIER
AIR ALOFT TODAY ALONG WITH SLIGHTLY STRONGER INSTABILITY ACTUALLY
RAISES THE MICROBURST THREAT SOME OVER YESTERDAY AND THINK THE
THREAT OF A PULSE SEVERE THUNDERSTORM IS A BIT GREATER TODAY.
WILL GET SOME UPDATED GRIDS WITH SLIGHTLY HIGHER POPS OUT ALONG THE
LAKE BREEZE SHORTLY.
IZZI
&&
.PREV DISCUSSION...
337 AM CDT
FORECAST FOCUS REMAINS ON HEAT/HUMIDITY OVER THE NEXT SEVERAL
DAYS...AND POTENTIAL FOR ISOLATED THUNDERSTORMS AGAIN THIS
AFTERNOON. HEAT HEADLINES MAY BE REQUIRED LATER IN THE WEEK FOR
CONSECUTIVE DAYS OF PEAK HEAT INDICES ABOVE 100.
00Z RAOB ANALYSIS DEPICTS 6000 METER 500MB HEIGHTS AT ILN...WITH
UPPER LEVEL RIDGE EXPECTED TO DRIFT ACROSS NORTHERN INDIANA LATER
TODAY AND ACROSS CENTRAL IL ON WEDNESDAY...BEFORE GRADUALLY
WEAKENING AND SHIFTING SOUTH ACROSS THE LOWER OHIO VALLEY LATE IN IN
THE WEEK. 850MB TEMPS OF +18/19C SAMPLED BENEATH THE RIDGE...WITH
MODEL FORECASTS INDICATING THESE SLOWLY WARMING AS THE RIDGE DRIFTS
WEST...REACHING +20/21C BY FRIDAY AS THE RIDGE DRIFTS SOUTH AND
WEST-SOUTHWEST LOW LEVEL FLOW ENHANCES WARM ADVECTION OFF THE
PLAINS. TEMPS MONDAY WERE GENERALLY 89-91 OUTSIDE OF THE LAKE BREEZE
AND THUNDERSTORM EFFECTS...AND DIAGNOSIS OF LOW LEVEL THERMAL FIELDS
FROM MODELS INDICATE WE SHOULD BE PERHAPS A DEGREE OR SO HIGHER
OVERALL TODAY...AND IN THE LOW-MID 90S WED-FRI. COMBINED WITH SFC
DEW POINT TEMPERATURES GENERALLY IN THE LOWER 70S...THE COMBINATION
OF HEAT/HUMIDITY SHOULD YIELD AFTERNOON PEAK HEAT INDEX VALUES
ROUGHLY 98-102 DEGREES FOR THE NEXT FOUR DAYS. MUGGY CONDITIONS WITH
NIGHTTIME TEMPS SLOWLY FALLING THROUGH THE MID/UPPER 70S WILL NOT
PROVIDE MUCH RELIEF AT NIGHT EITHER. THREE TO FOUR CONSECUTIVE DAYS
OF THESE CONDITIONS WOULD REQUIRE HEAT HEADLINES FOR THE CWA. THE
CAVEATS AT THIS TIME HOWEVER REMAINS THE POTENTIAL FOR ISOLATED
AFTERNOON THUNDERSTORMS AGAIN TODAY (AND WED/THU AS WELL) AND A
GREATER THREAT OF THUNDERSTORMS FRIDAY AFTERNOON WHICH COULD DISRUPT
TEMPS/HEAT INDEX VALUES DURING PEAK HEATING...AS WELL AS LOWERING
DEW POINT TEMPERATURES DURING AFTERNOON MIXING. WILL HOLD OFF ON
HOISTING ANY HEADLINES FOR NOW...AND MONITOR HOW THINGS PLAY OUT
THIS AFTERNOON.
SHIFTING TO THUNDERSTORM POTENTIAL...FORECAST SOUNDINGS CONTINUE TO
DEPICT UNSTABLE AND FAIRLY UNCAPPED THERMODYNAMIC PROFILES ACROSS
THE AREA AGAIN THIS AFTERNOON. WHILE NOT MUCH SUPPORT NOTED ON THE
LARGE SCALE...LACK OF SIGNIFICANT CAPPING DOES SUGGEST THE POTENTIAL
FOR AT LEAST A FEW ISOLATED THUNDERSTORMS THIS AFTERNOON
PARTICULARLY ACROSS NORTHERN PARTS OF THE IL CWA...WITH CONVERGENCE
ALONG WEAK LAKE BREEZE A POTENTIAL TRIGGER. CONVECTIVE OUTFLOW
BOUNDARIES FROM ANY ISOLATED STORMS THAT DO FORM WOULD ALSO PROVIDE
FOCUS FOR ADDITIONAL ISOLATED DEVELOPMENT...WHICH SHOULD WANE TOWARD
EVENING WITH LOSS OF DIURNAL COMPONENT OF INSTABILITY. THOUGH SPARSE
IN NUMBER AND COVERAGE...ANY STORMS THAT WOULD FORM WOULD LIKELY BE
SLOW-MOVING AND POTENTIALLY HEAVY RAIN PRODUCERS...WITH 2.03 INCH
PWAT NOTED IN DVN 00Z RAOB AND 1.90 INCHES AT ILX. WHILE AN ISOLATED
THUNDERSTORM MAY ALSO BE POSSIBLE WEDNESDAY AND THURSDAY
AFTERNOON...THE POTENTIAL SHOULD BE DECREASING AS THE RIDGE DRIFTS
CLOSER AND MID-LEVEL TEMPERATURES WARM. ALSO...IT APPEARS AS THOUGH
THERE WILL BE JUST ENOUGH WEST-SOUTHWEST FLOW IN LOW LEVELS AFTER
TODAY TO PREVENT THE LAKE BREEZE FROM MOVING INLAND...PROVIDING LESS
FOCUS FOR CONVECTIVE INITIATION.
AS INDICATED ABOVE...THE UPPER RIDGE IS ANTICIPATED TO WEAKEN AND
MOVE SOUTH THURSDAY AND FRIDAY...WITH MID/UPPER LEVEL WESTERLIES
SETTLING ACROSS THE UPPER MIDWEST. MODEL GUIDANCE REMAINS IN GOOD
AGREEMENT THAT AMPLIFICATION OF AN UPPER TROUGH WILL OCCUR ACROSS
CENTRAL CANADA AND THE UPPER MIDWEST BY FRIDAY NIGHT...WITH A COLD
FRONT SAGGING SOUTH INTO OUR AREA. THUNDERSTORM POTENTIAL LOOKS TO
INCREASE FRIDAY AFTERNOON AHEAD OF THE FRONT...AS LARGE SCALE ASCENT
DEVELOPS IN ADVANCE OF THE DEEPENING UPPER TROUGH AND LOW LEVEL
CONVERGENCE AND MOISTURE POOLING OCCUR ALONG AND SOUTH OF THE COLD
FRONTAL BOUNDARY. SOME LINGERING THREAT OF SHOWERS/THUNDERSTORMS MAY
LINGER INTO SATURDAY AS THE FRONT CONTINUES TO SAG SOUTHWARD...
THOUGH MAINLY ACROSS THE SOUTH/SOUTHEASTERN PARTS OF THE CWA. COOLER
AND LESS HUMID WEATHER CAN BE EXPECTED HOWEVER...AS HIGH PRESSURE
BUILDS SOUTHEAST ACROSS THE GREAT LAKES OVER THE WEEKEND AND SHIFTS
WINDS TO THE NORTH-NORTHEAST. A RETURN TO WARMER AND MORE HUMID
CONDITIONS LOOKS TO TAKE PLACE AGAIN EARLY NEXT WEEK HOWEVER...WITH
THE ECMWF QUICKER WITH THE RETURN MONDAY.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* POSSIBILITY OF LAKE BREEZE REACHING FAR ENOUGH INLAND DURING THE
LATER AFTERNOON TO AFFECT WIND DIRECTION AT ORD/MDW.
* CHANCE OF TSRA THIS AFTERNOON ALONG LAKE BREEZE.
* VISIBILITY REDUCTION DUE TO BR AND HZ LATE TONIGHT THROUGH EARLY
WED MORNING.
TRS/BMD
//DISCUSSION...UPDATED 12Z...
VERY SLOW WESTWARD RETROGRESSION OF THE UPPER PATTERN ACROSS
THE EASTERN AND CENTRAL U.S WILL CONTINUE TODAY...THEN TO THE
WEST-SOUTHWEST TONIGHT. THE W TO E ELONGATED UPPER ANTICYCLONE
THAT CURRENTLY IS OVER FAR WESTERN LOWER MI IS TO RETREAT TO
AROUND THE CENTRAL PORTION OF THE IL-IN BOARDER BY LATE TONIGHT.
THE ASSOCIATED SURFACE HIGH CENTER IS ALSO DRIFTING WESTWARD
RESULTING IN THE LOW LEVEL FLOW OVER THE AREA BACKING FROM
SOUTHEASTERLY TO SOUTHWESTERLY OVERNIGHT PER WIND PROFILES FROM
WSR-88D NETWORK AS WELL AS TERMINAL DOPPLER INSTALLATIONS.
THIS SW FLOW WILL BE RATHER WEAK WITH PROGGED MIXED LAYER WINDS
OF ONLY UP TO AROUND 10 KT AT MOST DURING THE DAY. WHILE WEAK IT
IS EXPECTED TO LIMIT ANY LAKE BREEZE INLAND PENETRATION TO JUST
ALONG THE IMMEDIATE SHORELINES OF NW IN AND UP TO AROUND DOWNTOWN
CHICAGO...WITH DEEPER PENETRATION INLAND THE FURTHER ONES GOES
FROM THE LOOP N UP TO SE WI. EVEN MODELS THAT ARE MOST AGGRESSIVE
WITH THE LAKE BREEZE ONLY TAKE IT AS FAR W AS THE EASTERN BOARDER
OF THE ORD AIR FIELD SO THE TAFOR MAINTAINS SW SURFACE WINDS
THROUGH THE DAY.
WITH SOMEWHAT STAGNANT CONDITIONS UNDER THE ANTICYCLONE AN
INCREASE IN PARTICULATE MATTER AND COUPLED WITH DEW POINTS
REMAINING IN THE LOWER 70S IS EXPECTED TO RESULT IN VISIBILITY
BEING RESTRICTED BY SMOG FROM LATE OVERNIGHT TIL A COUPLE HOURS
AFTERN SUNRISE WED. DO NOT ANTICIPATE PREVAILING VISIBILITY
CONDITIONS AT ORD OR MDW TO BE BELOW MVFR THOUGH POSSIBLE IT MAY
DIP INTO HIGHER END OF IFR AROUND SUNRISE.
TRS
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* HIGH CONFIDENCE IN LAKE BREEZE DEVELOPING AND AT LEAST MOVING
INTO THE VICINITY OF THE TERMINALS...LOW CONFIDENCE ON REACHING
TERMINALS.
* LOW TO MEDIUM CONFIDENCE IN ISOLATED/SCATTERED CONVECTION
DEVELOPING PARTICULARLY ALONG THE LAKE BREEZE.
* MODERATE CONFIDENCE IN VISIBILITY RESTRICTION OVERNIGHT AND
EARLY WED MORNING.
* HIGH CONFIDENCE ALL OTHER FORECAST PARAMETERS.
TRS/BMD
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...MVFR VISIBILITY OVERNIGHT DUE TO BR HZ.
OTHERWISE...VFR...NO SIG WX.
THURSDAY...POSSIBLE MVFR VISIBILITY EARLY MORNING AND LATE
OVERNIGHT DUE TO BR HZ. OTHERWISE...VFR...NO SIG WX.
FRIDAY...INCREASING CHANCES OF TS AS DAY PROGRESSES...FROM SLIGHT
CHANCE IN THE MORNING TO CHANCE IN AFTERNOON AND LIKELY FRIDAY
NIGHT. ANY TSRA WOULD PRODUCE OF MVFR AND POSSIBLY BRIEF IFR
CONDITIONS.
SATURDAY...SLIGHT CHANCE OF TS. OTHERWISE VFR.
SUNDAY...VFR...NO SIG WX.
MONDAY...CHANCE OF TSRA...OTHERWISE VFR.
&&
.MARINE...
339 AM CDT
A LARGE AREA OF HIGH PRESSURE CENTERED OVER THE OH VALLEY EARLY
THIS MORNING WILL CONTINUE TO SLOWLY SHIFT TO THE W AND WILL BE
CENTERED IN THE MID MS VALLEY BY WED NIGHT MAINTAINING LIGHT TO
GENTLE S TO SW BREEZES ON THE LAKE. DURING THU AND THU NIGHT SW
WINDS WILL GRADUALLY FRESHEN AS A COLD FRONT DROPS S ACROSS THE
N WOODS AND LAKE SUPERIOR WHERE IT WILL WEAKEN. A STRONGER COLD
FRONT WILL DROP S OVER NORTHERN LAKE MI DURING FRI AFTERNOON
WITH THE COLD FRONT CONTINUING S DOWN THE LAKE REACHING THE S
END BY DAWN SAT. HIGH PRESSURE BUILDING SE FROM CENTRAL CANADA
TO THE UPPER MIDWEST DURING FRI NIGHT AND SAT WILL MAINTAIN
GENTLE TO MODERATE N TO NE BREEZES THROUGH THAT PERIOD.
TRS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS GRAY ME
622 AM EDT TUE JUL 16 2013
.SYNOPSIS...
HIGH PRESSURE ANCHORED OVER THE MIDWEST AND EXTENDING INTO NEW
ENGLAND WILL PROVIDE CONTINUED WARM SUMMERTIME TEMPERATURES. A
SERIES OF SHORTWAVES RIPPLING ACROSS THE CANADIAN BORDER THROUGH
FRIDAY WILL PROVIDE INCREASING CHANCES FOR SHOWERS AND
THUNDERSTORMS. A VIGOROUS FRONT WILL CROSS THE AREA ON SATURDAY,
BRINGING A RESPITE FROM THE HEAT SUNDAY AND MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
620 AM UPDATE...06 UTC NAM AND 09 UTC RAP SHOWING WEAKER FORCING
THIS AFTERNOON FOR CONVECTION ALONG THE WEAK BOUNDARY TO DRAPE
ACROSS NEW ENGLAND THIS AFTERNOON. HAVE CUT ALL AFTERNOON POPS TO
LESS THAN 30 PERCENT. OTHERWISE JUST A FEW TWEAKS TO MATCH CURRENT
OBSERVATIONS.
402 AM ISSUANCE...CLEAR SKIES THIS MORNING WILL GIVE WAY TO SOME SCATTERED
CUMULUS DEVELOPMENT, ESPECIALLY OVER THE HIGHER TERRAIN. RAP/NAM
SHOWING A BOUNDARY SET TO BE LYING FROM SOUTHERN QUEBEC THROUGH
EASTERN NEW HAMPSHIRE THIS AFTERNOON. FEATURE IS PRETTY SUBTLE AND
MAY NOT BE ENOUGH TO FIRE CONVECTION, BUT HAVE ADDED ISOLATED
THUNDER THIS AFTERNOON AND EVENING ACROSS MOSTLY INTERIOR EASTERN
NEW HAMPSHIRE AND SOUTHWEST MAINE. HOT AGAIN TODAY WITH HIGHS FROM
THE MID 80S TO LOWER 90S AND CONTINUED DEW POINT TEMPERATURES IN
THE MID 60S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
SOME VALLEY FOG IS EXPECTED TONIGHT AS DEW POINTS CLIMB SLIGHTLY.
TEMPERATURES WILL BOTTOM OUT AGAIN IN THE 60S IN MOST LOCATIONS. A
SHORTWAVE WILL THEN APPROACH THE AREA ON WEDNESDAY AFTERNOON.
PRECIPITABLE WATER VALUES ARE FORECAST TO APPROACH 2 STANDARD
DEVIATIONS ABOVE NORMAL, PLUS FORCING TRIGGERED BY THE SHORTWAVE
AND AMPLE BULK SHEAR AND BUOYANCY WILL PROVIDE THE THREAT FOR
SEVERE CONVECTION -- ESPECIALLY ALONG THE CANADIAN BORDER. HIGHS
ARE EXPECTED TO BE 1-3F COOLER ON WEDNESDAY COMPARED TO TODAY`S
FORECAST HIGHS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
SFC BOUNDARY ATTENDANT TO S/WV TROF WILL SLOWLY SAG SWD THRU THE
CWFA WED NIGHT INTO THU. IT WILL REMAIN A FOCUS FOR SHRA AND TSTMS
OVERNIGHT...AND AGAIN WITH DIURNAL HEATING ON THU. STRONG
INSOLATION IN A MOIST ENVIRONMENT WILL PROVIDE PLENTY OF
INSTABILITY FOR STRONGER STORMS. STEADILY INCREASING MID LVL FLOW
WILL ALSO PROVIDE ENOUGH SHEAR FOR SOME STORM ORGANIZATION. THE
STRONGER CONVECTIVE ELEMENTS THU AFTERNOON WILL BE CAPABLE OF
GUSTY WINDS...BUT PWAT VALUES CLIMBING TOWARDS +2 SD ABOVE NORMAL
WILL KEEP HEAVY RNFL AS THE MORE WIDESPREAD THREAT.
ATTENTION THEN TURNS TO FRI AND SAT WHERE A SEASONABLY STRONG UPR
TROF WILL DIG ACROSS THE NRN TIER OF CONUS. THIS WILL DRIVE A
STRONG COLD FNT THRU THE REGION ON SAT. HOT AND HUMID AIR MASS IN
PLACE AHEAD OF THE FNT WILL PROVIDE AMPLE INSTABILITY. 16/00Z GFS
ENSEMBLES THEN INDICATE THAT H8 WIND FIELD WILL STRENGTHEN TO
AROUND 40 KT...NEARLY 2 SD ABOVE NORMAL FOR THIS TIME OF YEAR.
THIS ANOMALOUSLY STRONG FLOW WILL MEAN STORM ORGANIZATION IS
LIKELY...WITH DEEP UNIDIRECTIONAL FLOW FAVORING LINE SEGMENTS AND
CLUSTERS. THE STRONG FLOW ALOFT WILL SUPPORT A WIND DAMAGE
THREAT...AND CONTINUED HIGH PWATS WILL ALSO MEAN HEAVY RNFL. STORM
MOTION WILL BE FASTER THAN PAST WEEKS...BUT THE GRADUAL APPROACH
OF THE COLD FNT COULD MEAN SEVERAL ROUNDS OF TSTMS FOR SOME OF THE
SAME AREAS. REPEATED HEAVY PCPN EVENTS FOR THE NRN MTNS COULD MEAN
FLASH FLOOD REMAINS ELEVATED...DESPITE QUICKLY MOVING STORMS. THE
AREA REMAINS IN THE STORM PREDICTION CENTER/S DAY 4 TROUGH 8
SEVERE WEATHER OUTLOOK.
AFTER COLD FNT PUSHES THRU THE CWFA...COOLER AND MUCH DRIER AIR
WILL REPLACE THE STAGNANT AIR MASS OF THE LAST FEW WEEKS. EXPECT
HIGH TEMPS TO DROP BACK INTO THE 70S TO NEAR 80...WITH OVERNIGHT
LOW DIPPING INTO THE 50S AND CLOSER TO NORMAL.
&&
.AVIATION /10Z TUESDAY THROUGH SATURDAY/...
SHORT TERM...VFR THIS MORNING EXCEPT FOR SOME PATCHY VALLEY FOG.
FOG WILL AGAIN APPEAR IN VALLEYS WEDNESDAY MORNING. ISOLATED MVFR
IN THUNDERSTORMS THIS AFTERNOON THEN MORE NUMEROUS ON WEDNESDAY.
LONG TERM...VFR CONDS EXPECTED TO PREVAIL THRU THE WEEKEND. LOCAL
MVFR/IFR CIGS AND VSBYS ARE POSSIBLE IN VALLEY FOG OVERNIGHT THRU
FRI. SCT SHRA/TSTMS WILL BE INCREASINGLY LIKELY EACH AFTERNOON
THRU SAT.
&&
.MARINE...
SHORT TERM...LIGHT WINDS AND CALM SEAS TODAY, THEN INCREASING
SOUTHERLY WINDS ON WEDNESDAY AFTERNOON SHOULD PUSH SEAS TO 3 TO 4
FEET.
LONG TERM...CONTINUED SWLY FLOW AHEAD OF APPROACHING COLD FNT WILL
BRING SEAS UP TO 5 FT OR HIGHER BY THE LATE WEEK AND EARLY
WEEKEND.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...STJEAN
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
935 AM EDT TUE JUL 16 2013
.SYNOPSIS...
HIGH PRESSURE WILL PROMOTE WARM AND HUMID CONDITIONS THIS WEEK.
THUNDERSTORM CHANCES WILL INCREASE WITH A SATURDAY COLD FRONT.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
ADJUSTMENTS TO HOURLY TRENDS WERE THE ONLY ADJUSTMENTS NEEDED FOR
THE MID MRNG UPDATE.
PREVIOUS...
THE HRRR AND THE LAMP SEEM TO BE HANDLING THE CURRENT TEMPERATURE
TRENDS QUITE WELL EARLY THIS MORNING...SO THEY WERE USED THROUGH
THE DAY TODAY. THIS BRINGS THE DEWPOINTS UP THROUGH THE AFTERNOON
WHICH IN TURN BRINGS APPARENT TEMPERATURES INTO THE MID TO UPPER
90S OVER MY EASTERN OH...SOUTHWESTERN PA...AND NORTHERN WV
PANHANDLE COUNTIES. THUS...AN SPS WILL BE ISSUED WITH THE MORNING
PACKAGE FOR HOT TEMPERATURES AS IT WILL BE JUST UNDER HEAT
ADVISORY CRITERIA.
THE MID LEVEL HIGH WILL CONTINUE TO SHIFT WESTWARD TODAY ALLOWING
FOR THE CAP TO WEAKEN THIS AFTERNOON. THIS COULD ALLOW FOR A BIT
MORE THUNDERSTORM COVERAGE THAN YESTERDAY...MAINLY ALONG THE LAKE
BREEZE BOUNDARY TO THE NORTH AND IN THE HIGHER ELEVATIONS.
HOWEVER...THE HI RES MODELS ARE SUGGESTING THAT A FEW
SHOWERS/THUNDERSTORMS COULD DEVELOP A BIT FURTHER SOUTH AND
WEST...SO A ISOLATED THUNDERSTORM MENTION WAS ADDED TO ALL OF THE
FORECAST AREA BY LATE AFTERNOON. CONFIDENCE IN THIS COVERAGE
REMAINS LOW HOWEVER...ESPECIALLY OVER EASTERN OHIO...SO FELT AN
ISOLATED MENTION WOULD SUFFICE.
HIGH PRES WILL CONTINUE TO SLOWLY MOVE WESTWARD THROUGH THE
PERIOD. CONTINUED A SLIGHT CHANCE MENTION FOR THUNDERSTORMS NORTH
AND ALONG THE RIDGES WEDNESDAY. APPARENT TEMPERATURES WILL ONCE
AGAIN GET VERY CLOSE TO 100 DEGREES WEDNESDAY AFTERNOON. FOR
NOW...WILL CONTINUE TO HIGHLIGHT HOT...HUMID WEATHER IN THE HWO.
BIAS CORRECTED MOS WAS USED FOR TEMPERATURES...WITH ABOVE SEASONAL
VALUES EXPECTED BOTH DAY AND NIGHT.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
VERY HUMID AMS WILL PERSIST THRU THE WK OWING TO STAGNANT FLOW
AMID FLATTENING H5 RDG. BY THU...MID-LVL FLOW WILL INCR SLGTLY AS
JET STREAM ACRS CANADA SINKS EQUATORWARD.
CAP STILL XPCD TO BE PRESENT ON THU...BUT SOMEWHAT WKR THAN PREV
DAYS OWING TO WWD DEPARTURE OF RDG. VERY MODEST CNVGNC ALONG
INVERTED SFC TROF AND TERRAIN CIRCULATIONS WILL PROVIDE ONLY CLR
FOCI FOR ANY CNVCTV DVLPMT THU AFTN. ISOLD-SCT CVRG OF TSTMS WERE
INCLUDED ON THU...SUBSIDING THU EVE WITH LOSS OF HEATING.
BELT OF MDT WSWLY H5 FLOW SPREADS SWD ON FRI AS AGGRESSIVE TROF
DIGS INTO S-CNTRL CANADA AND NRN PLNS. PRIMARY FOCUS FOR TSTM
DVLPMT WILL BE ALONG ASSOCIATED CDFNT MAINLY NW OF FCST AREA. BUT
GIVEN INCRG LIFT AND QUALITY INSOLATION...TSTMS CANNOT BE RULED
OUT ON FRI. MDT-STG INSTBY MAY COMPENSATE FOR MODEST SHEAR AND
COULD PROMOTE A THREAT OF SVR TSTMS WITH DMGG WIND GUSTS ON FRI
AFTN.
MAXIMA XPCD TO BE CAPPED IN THE LWR 90S OWING TO VERY HIGH MSTR
CONTENT OF BNDRY LYR. THE COMBINATION OF LWR 90S TEMPS AND DEWPT
TEMPS IN THE LWR-MID 70S WILL YIELD HEAT INDICES IN THE UPR 90S-NR
100 BOTH WED AND THU. HEAT CONCERNS WILL BE HIGHLIGHTED IN HWO.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
SGFNT SVR EPISODE RMNS PSBL ON SAT AS VERY HUMID AMS WILL RMN IN
THE RGN IN ADVC OF ARRIVING CDFNT. H5 FLOW WILL INCR FRI NGT-SAT
AS SHRTWV TROF CROSSES GRTLKS RGN. CNVCTN XPCD TO DVLP RELATIVELY
EARLY ON SAT ALONG AND AHD OF ADVCG CDFNT.
STG INSTBY AND MDT BULK SHEAR WILL SUPPORT ORGANIZED UPDRAFTS.
SHEAR VECTOR WILL BE RELATIVELY PARALLEL TO ADVCG CDFNT...SO
CNVCTN XPCD TO BCM LINEAR RELATIVELY QUICKLY. OWING TO VERY HIGH
FRZG LVLS AND STEEP LAPSE RATES...DMGG WIND GUSTS WILL BE PRIMARY
SVR THREAT FROM THESE TSTMS.
CDFNT CROSSES RGN BY SAT EVE AND SCOURS OUT MSTR. PCPN WILL SHIFT
SE OF FCST AREA BY SUN AFTN. TEMPS WILL TREND TWD LWR 80S EARLY
NEXT WK IN WAKE OF CDFNT PASSAGE.
NELY UPSLP FLOW ON MON MAY SUPPORT A FEW SHWRS ALONG TERRAIN.
GUIDANCE SUGGESTS A SHRTWV TROF WILL STRENGTHEN SWLY LOW-LVL FLOW
BY TUE AND WILL PROMOTE INCRG CHCS FOR TSTMS AS BNDRY-LYR MSTR
INCRS.
&&
.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
GENERAL VFR EXPECTED AT ALL SITES TODAY. EXPECT DIURNAL CU TO
DEVELOP ONCE AGAIN...BUT BE MORE WIDESPREAD IN COVERAGE WITH
WESTWARD TRACKING HIGH. THIS COULD ALSO PROMOTE A BIT MORE
SHOWER/THUNDERSTORM DEVELOPMENT IN BOTH THE LAKE BREEZE AND ALONG
THE RIDGES. WITHOUT SOLID CONFIDENCE THAT ANY SITE WILL BE
IMPACTED...LEFT SHRA/TSRA MENTION OUT FOR NOW.
WINDS WILL REMAIN LIGHT AND VARIABLE.
.OUTLOOK.../TUESDAY NIGHT THROUGH SATURDAY/...
RESTRICTIONS IN MRNG FOG WILL BE PSBL EACH DAY. BEST CHC FOR MORE
WDSPRD RESTRICTIONS WILL BE SAT AS CDFNT PASSAGE INVIGORATES BROAD
CVRG OF TSTMS IN THE RGN.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
15
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
639 AM EDT TUE JUL 16 2013
.SYNOPSIS...
HOT AND HUMID CONDITIONS ARE EXPECTED THROUGH THE WEEK AS HIGH
PRESSURE DOMINATES THE WEATHER. THUNDERSTORM CHANCES WILL INCREASE
FRIDAY AND SATURDAY AS A COLD FRONT APPROACHES AND CROSSES THE
REGION.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
THE HRRR AND THE LAMP SEEM TO BE HANDLING THE CURRENT TEMPERATURE
TRENDS QUITE WELL EARLY THIS MORNING...SO THEY WERE USED THROUGH
THE DAY TODAY. THIS BRINGS THE DEWPOINTS UP THROUGH THE AFTERNOON
WHICH IN TURN BRINGS APPARENT TEMPERATURES INTO THE MID TO UPPER
90S OVER MY EASTERN OH...SOUTHWESTERN PA...AND NORTHERN WV
PANHANDLE COUNTIES. THUS...AN SPS WILL BE ISSUED WITH THE MORNING
PACKAGE FOR HOT TEMPERATURES AS IT WILL BE JUST UNDER HEAT
ADVISORY CRITERIA.
THE MID LEVEL HIGH WILL CONTINUE TO SHIFT WESTWARD TODAY ALLOWING
FOR THE CAP TO WEAKEN THIS AFTERNOON. THIS COULD ALLOW FOR A BIT
MORE THUNDERSTORM COVERAGE THAN YESTERDAY...MAINLY ALONG THE LAKE
BREEZE BOUNDARY TO THE NORTH AND IN THE HIGHER ELEVATIONS.
HOWEVER...THE HI RES MODELS ARE SUGGESTING THAT A FEW
SHOWERS/THUNDERSTORMS COULD DEVELOP A BIT FURTHER SOUTH AND
WEST...SO A ISOLATED THUNDERSTORM MENTION WAS ADDED TO ALL OF THE
FORECAST AREA BY LATE AFTERNOON. CONFIDENCE IN THIS COVERAGE
REMAINS LOW HOWEVER...ESPECIALLY OVER EASTERN OHIO...SO FELT AN
ISOLATED MENTION WOULD SUFFICE.
HIGH PRES WILL CONTINUE TO SLOWLY MOVE WESTWARD THROUGH THE
PERIOD. CONTINUED A SLIGHT CHANCE MENTION FOR THUNDERSTORMS NORTH
AND ALONG THE RIDGES WEDNESDAY. APPARENT TEMPERATURES WILL ONCE
AGAIN GET VERY CLOSE TO 100 DEGREES WEDNESDAY AFTERNOON. FOR
NOW...WILL CONTINUE TO HIGHLIGHT HOT...HUMID WEATHER IN THE HWO.
BIAS CORRECTED MOS WAS USED FOR TEMPERATURES...WITH ABOVE SEASONAL
VALUES EXPECTED BOTH DAY AND NIGHT.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
VERY HUMID AMS WILL PERSIST THRU THE WK OWING TO STAGNANT FLOW
AMID FLATTENING H5 RDG. BY THU...MID-LVL FLOW WILL INCR SLGTLY AS
JET STREAM ACRS CANADA SINKS EQUATORWARD.
CAP STILL XPCD TO BE PRESENT ON THU...BUT SOMEWHAT WKR THAN PREV
DAYS OWING TO WWD DEPARTURE OF RDG. VERY MODEST CNVGNC ALONG
INVERTED SFC TROF AND TERRAIN CIRCULATIONS WILL PROVIDE ONLY CLR
FOCI FOR ANY CNVCTV DVLPMT THU AFTN. ISOLD-SCT CVRG OF TSTMS WERE
INCLUDED ON THU...SUBSIDING THU EVE WITH LOSS OF HEATING.
BELT OF MDT WSWLY H5 FLOW SPREADS SWD ON FRI AS AGGRESSIVE TROF
DIGS INTO S-CNTRL CANADA AND NRN PLNS. PRIMARY FOCUS FOR TSTM
DVLPMT WILL BE ALONG ASSOCIATED CDFNT MAINLY NW OF FCST AREA. BUT
GIVEN INCRG LIFT AND QUALITY INSOLATION...TSTMS CANNOT BE RULED
OUT ON FRI. MDT-STG INSTBY MAY COMPENSATE FOR MODEST SHEAR AND
COULD PROMOTE A THREAT OF SVR TSTMS WITH DMGG WIND GUSTS ON FRI
AFTN.
MAXIMA XPCD TO BE CAPPED IN THE LWR 90S OWING TO VERY HIGH MSTR
CONTENT OF BNDRY LYR. THE COMBINATION OF LWR 90S TEMPS AND DEWPT
TEMPS IN THE LWR-MID 70S WILL YIELD HEAT INDICES IN THE UPR 90S-NR
100 BOTH WED AND THU. HEAT CONCERNS WILL BE HIGHLIGHTED IN HWO.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
SGFNT SVR EPISODE RMNS PSBL ON SAT AS VERY HUMID AMS WILL RMN IN
THE RGN IN ADVC OF ARRIVING CDFNT. H5 FLOW WILL INCR FRI NGT-SAT
AS SHRTWV TROF CROSSES GRTLKS RGN. CNVCTN XPCD TO DVLP RELATIVELY
EARLY ON SAT ALONG AND AHD OF ADVCG CDFNT.
STG INSTBY AND MDT BULK SHEAR WILL SUPPORT ORGANIZED UPDRAFTS.
SHEAR VECTOR WILL BE RELATIVELY PARALLEL TO ADVCG CDFNT...SO
CNVCTN XPCD TO BCM LINEAR RELATIVELY QUICKLY. OWING TO VERY HIGH
FRZG LVLS AND STEEP LAPSE RATES...DMGG WIND GUSTS WILL BE PRIMARY
SVR THREAT FROM THESE TSTMS.
CDFNT CROSSES RGN BY SAT EVE AND SCOURS OUT MSTR. PCPN WILL SHIFT
SE OF FCST AREA BY SUN AFTN. TEMPS WILL TREND TWD LWR 80S EARLY
NEXT WK IN WAKE OF CDFNT PASSAGE.
NELY UPSLP FLOW ON MON MAY SUPPORT A FEW SHWRS ALONG TERRAIN.
GUIDANCE SUGGESTS A SHRTWV TROF WILL STRENGTHEN SWLY LOW-LVL FLOW
BY TUE AND WILL PROMOTE INCRG CHCS FOR TSTMS AS BNDRY-LYR MSTR
INCRS.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
GENERAL VFR EXPECTED AT ALL SITES TODAY AFTER MORNING FOG BURNS
OFF. KFKL...KDUJ...KZZV...AND KHLG ARE CURRENTLY EXPERIENCING IFR
VISIBILITIES THAT SHOULD GRADUALLY IMPROVE TO VFR THIS MORNING.
EXPECT DIURNAL CU TO DEVELOP ONCE AGAIN...BUT BE MORE WIDESPREAD IN
COVERAGE WITH WESTWARD TRACKING HIGH. THIS COULD ALSO PROMOTE A
BIT MORE SHOWER/THUNDERSTORM DEVELOPMENT IN BOTH THE LAKE BREEZE
AND ALONG THE RIDGES. WITHOUT SOLID CONFIDENCE THAT ANY SITE WILL
BE IMPACTED...LEFT SHRA/TSRA MENTION OUT FOR NOW.
WINDS WILL REMAIN LIGHT AND VARIABLE.
.OUTLOOK.../TUESDAY NIGHT THROUGH SATURDAY/...
RESTRICTIONS IN MRNG FOG WILL BE PSBL EACH DAY. BEST CHC FOR MORE
WDSPRD RESTRICTIONS WILL BE SAT AS CDFNT PASSAGE INVIGORATES BROAD
CVRG OF TSTMS IN THE RGN.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
723 AM EDT TUE JUL 16 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 419 AM EDT TUE JUL 16 2013
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW SPRAWLING UPR RDG
CENTERED OVER THE LOWER GRT LKS. ALTHOUGH THE 00Z GRB RAOB INDICATES
THE TROPOSPHERE OVER THE UPR GRT LKS HAS MOISTENED CONSIDERABLY OVER
THE LAST DAY OR SO WITH 00Z PWAT UP TO 1.82 INCHES /185 PERCENT OF
NORMAL/...MID LVL WARMTH WITH H5 TEMPS ARND -5C HAS MAINTAINED
RATHER UNIMPRESSIVE MID LVL LAPSE RATES IN THE ABSENCE OF ANY
DYNAMIC FORCING UNDER THE RDG. THE CONVECTIVE TEMP ON THE 00Z GRB
SDNG WAS 94. A FEW -SHRA DID POP UP OVER WI YDAY AFTN...BUT THESE
DISSIPATED LAST EVNG WITH THE LOSS OF DAYTIME HEATING. HOWEVER...
MORE ISOLD -SHRA HAVE DVLPD OVER NW WI/ADJOINING MN IN AREA WHERE
RUC ANALYSIS SHOWS KINX NEAR 36. PERSISTENT BAND OF MSTR THAT HAS
PLAGUED NE MN/NW LK SUP WITH CLDS/SOME SHRA THE LAST FEW DAYS HAS
DRIFTED TO THE N INTO ONTARIO. OTRW...SFC TEMPS ARE RUNNING WELL ABV
NORMAL EARLY THIS MRNG DESPITE CLR-PCLDY SKIES. TO THE NW...THERE IS
A STRONGER SHRTWV JUST W OF LK WINNIPEG MOVING ENEWD THRU SRN CANADA.
MAIN FCST CONCERNS IN THE SHORT TERM ARE TEMPS AND SHRA/TS CHCS AS
UPR RDG REMAINS DOMINANT OVER THE GRT LKS.
TODAY...CENTER OF UPR RDG/SFC HI PRES OVER THE LOWER GRT LKS IS FCST
TO DRIFT ONLY SLOWLY TO THE W...SO MID LVL WARM AIR WL REMAIN OVER
THE CWA. STRONGER SHRTWV/ACCOMPANYING DYNAMICS LIFTING ENEWD THRU
SCENTRL CANADA WL RIDE WELL TO THE N OF UPR MI AND NOT IMPACT THE
CWA. BUT WITH DAYTIME HEATING...BULK OF NUMERICAL MODELS GENERATE
SHRA/TS OVER UPR MI TODAY. THERE ARE A NUMBER OF NEGATIVES FOR
PCPN...THE ABSENCE OF ANY DYNAMIC FORCING...FCST ACYC H85 SW FLOW
THAT WL RESULT IN ONLY WEAK LK BREEZE DVLPMENT OFF LK SUP...AND VERY
HI CONVECTIVE TEMP SHOWN ON THE 00Z GRB RAOB. HOWEVER...WITH SOME
ISOLD -SHRA OVER NW WI...SUSPECT SOME SHRA/TS WL IMPACT UPR MI
MAINLY BY LATE MRNG AFTER ONSET OF DAYTIME HEATING. FCST DRYING IN
THE AFTN IN THE WAKE OF AREA OF HIER KINX NOW MOVING TOWARD THE CWA
MAY CAUSE THE SHRA TO DIMINISH DESPITE MOVING TOWARD PEAK HEATING
TIME. THE BEST CHC FOR MORE PERSISTENT SHRA/TS WL BE OVER THE
ECENTRL CWA ON THE EDGE OF THE LK BREEZE BNDRY MOVING ONSHORE FM LK
MI. WITH FCST H85 TEMPS ARND 19C...EXPECT ANOTHER WARM DAY WITH MAX
TEMPS WELL INTO THE 80S TO LO 90S OVER THE INTERIOR. HIER HUMIDITY
WL MAKE THE AIR FEEL QUITE UNCOMFORTABLE...WITH APPARENT TEMPS
RISING TO ARND 95 AT SOME PLACES.
TNGT...COLD FNT ATTENDANT TO DISTURBANCE MOVING THRU CANADA AND INTO
HUDSON BAY IS PROGGED TO DRIFT S INTO NRN LK SUP BY 12Z WED UNDER
MODEST H5 HGT FALLS. CURRENT FCST SHOWS OVERNGT POPS OVER NRN LK SUP
CLOSE TO THIS INCOMING BNDRY AND AREA OF HIER FCST MID LVL RH...SO
WL RESTRICT FCST POPS TO THIS AREA AND KEEP THE REST OF THE CWA DRY
CLOSER TO HI PRES/CORE OF WARMER MID LVL AIR. WITH FCST H925 WINDS
UP TO 25-30 KTS UNDER SHARPENING PRES GRADIENT TO THE S OF THIS
INCOMING FNT...OVERNGT LO TEMPS SHOULD BE FAIRLY WARM...ESPECIALLY
IN THE DOWNSLOPE AREAS NEAR LK SUP.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 419 AM EDT TUE JUL 16 2013
STARTING OUT THE LONG TERM AT 12Z WED...THE CWA WILL BE BETWEEN AN
UPPER HIGH CENTERED OVER IN AND A LOW PRESSURE SYSTEM OVER NRN
HUDSON BAY. STRETCHING FROM THE HUDSON BAY LOW WILL BE A
TROUGH/FRONT OVER QUEBEC SW TO THE NRN CWA. THE FRONT WILL NOT MOVE
MUCH THROUGH THU...WITH SLOW SOUTHERLY MOVEMENT OR NEARLY STATIONARY
BEHAVIOR EXPECTED. WIND FIELDS WILL BE NEAR UNIDIRECTIONAL AND FOR
THE MOST PART PARALLEL TO THE FRONT. WITH INSTABILITY ALONG AND S OF
THE FRONT...EXPECT CONVECTION FOR MUCH OF THE PERIOD. TROUBLE COMES
WITH POSSIBILITIES OF STRONG TO SEVERE STORMS AND FLOODING. WINDS
PARALLEL TO THE SLOW MOVING FRONT AND PWATS OF 1.5-2.0 INCHES
/150-200 PERCENT OF NORMAL/ COMBINED WITH INSTABILITY MAY MAKE FOR
SOME AREAS RECEIVING EXCESSIVE RAINFALL...BUT IT IS TOO DIFFICULT AT
THIS TIME FRAME TO TELL WHERE EXACTLY THAT WILL BE /MORE OF A
NOWCASTING ISSUE/. AS FOR STRONG-SEVERE POTENTIAL WED-THU...THE BEST
CHANCE FOR GOOD INSTABILITY LOOKS TO BE ON WED AS THE FRONT WILL BE
MOVING INTO UPPER MI...WHILE THU LOOKS MORE UNCERTAIN SINCE THE
POSITION OF THE FRONT AND CLOUD COVER ARE MORE IN QUESTION.
FOR THE SPECIFICS FOR WED...CAPE VALUES OF 1500-2500J/KG ARE
POSSIBLE AS SFC TEMPS WARM INTO THE 80S TO AROUND 90. 0-6KM BULK
SHEAR LOOKS TO BE AROUND 30KTS /AS PREVIOUSLY STATED...THAT IS
MOSTLY UNIDIRECTIONAL/. DCAPE VALUES LOOK TO BE AOB 1000J/KG THANKS
TO SOME DRY LAYERS IN THE SOUNDING...WHICH MAY HELP GET SOME STRONG
WINDS OUT OF STORMS. MAY SEE THUNDERSTORMS INITIATE IN THE
AFTERNOON...OR COULD EVEN SEE A CONVECTIVE COMPLEX MOVE ALONG THE
FRONT. WITH WEAK SFC WINDS...MAY SEE CONVECTION FOCUSING ON LAKE
FREEZES THAT FORM. CONVECTION MAY THEN CONTINUE INTO WED NIGHT...BUT
WOULD MORE LIKELY BE ELEVATED WITH STRONG/SEVERE POTENTIAL
CONTINUING DUE TO AN INCREASE IN THE NOCTURNAL LOW LEVEL JET...BUT
IT WOULD LIKELY DEPEND MORE ON THE PATH OF ANY CONVECTIVE COMPLEXES
THAT MAY FORM.
THU...AS SAID BEFORE...MORE UNCERTAINTY WITH CONVECTIVE CHANCES DUE
TO QUESTIONS ABOUT FRONTAL LOCATION AND CLOUD COVER. SHOULD BE LESS
DCAPE AS MORE MOISTURE WILL HAVE MOVED INTO THE AREA...SO OVERALL
THINK THE CHANCE OF STRONGER/SEVERE STORMS IS MORE LIMITED THAN WED.
SHOULD SEE CONVECTION CONTINUE INTO THU NIGHT AS HEIGHT FALLS MOVE
INTO THE REGION AS THE UPPER LOW DROPS TO SRN HUDSON BAY...WHICH
WILL BOOST FORCING ACROSS THE CWA WHILE THE FRONT REMAINS FAIRLY
STATIONARY. THREAT OF HEAVY RAIN/TRAINING STORMS CONTINUES...BUT THE
LOCATION IS AGAIN NEARLY IMPOSSIBLE TO PINPOINT AT THIS TIME. SFC
TEMPS SHOULD BE COOLER IN THE 70S TO MID 80S.
FRI-SAT...THE UPPER LOW WILL WEAKEN WHILE MOVING TO JAMES BAY BY 12Z
SAT...THEN TO NRN QUEBEC BY 00Z SUN. THIS WILL ALLOW A MORE
SIGNIFICANT UPPER TROUGH TO SWING ACROSS THE CWA FRI INTO
SAT...WHICH WILL PUSH THE COLD FRONT WELL S OF THE CWA BY FRI NIGHT.
MAY STILL SEE SOME SHOWERS ON FRI AFTERNOON AS THE TROUGH PUSHES
IN...BUT TEMPS WILL BE COOLER WITH HIGHS IN THE 70S TO LOW 80S IN
MOST LOCATIONS. ALTHOUGH THE UPPER TROUGH IS STILL MOVE THROUGH
SAT...SFC HIGH PRESSURE AND ASSOCIATED DRY AIR OVER THE CWA SHOULD
KEEP THINGS DRY FOR THE MOST PART. HIGHS SAT LOOK TO BE IN THE 60S
AND 70S.
THERE IS THE POSSIBILITY OF ANOTHER TROUGH MOVING THROUGH ON SUN AND
MON /BEST CHANCES ON MON/...WHICH WOULD LEAD TO PRECIP ACROSS MUCH
OF THE CWA. HOWEVER...CONFIDENCE ON THE POSITION/TIMING/EXTENT OF
THE TROUGH IS LOW AT THIS POINT...SO WILL JUST CONTINUE TO LOAD A
CONSENSUS OF MODELS INTO FORECAST FOR THIS TIME PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 722 AM EDT TUE JUL 16 2013
A TS MOVING NEWD ALONG THE W COAST OF UPR MI WL IMPACT CMX EARLY IN
THE FCST PERIOD WITH SOME GUSTY WINDS/BRIEF +SHRA. MORE ISOLD
SHRA/TS WL THEN POPUP WITH DAYTIME HEATING AND PSBLY IMPACT THE TAF
SITES BEFORE THE ARRIVAL OF DRYING ALF TENDS TO DIMINISH THIS
ACTIVITY IN THE AFTN. CONFIDENCE IN TIMING/PLACEMENT OF ANY OF THESE
SHRA/TS IS TOO LO TO INCLUDE IN ANY OF THE TAFS RIGHT NOW. WITH
DAYTIME HEATING/MIXING...A GUSTY SW WIND WL DVLP. EXCEPT FOR UNDER
THE HEAVIER SHRA...VFR CONDITIONS WL PREDOMINATE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 419 AM EDT TUE JUL 16 2013
WITH WEAK PRES GRADIENT AND HI STABILITY OVER THE RELATIVELY CHILLY
LAKE WATERS...EXPECT LIGHT WINDS UNDER 20 KTS THRU TONIGHT. THE
PERSISTENCE OF A FAIRLY HUMID AIRMASS OVER THE LAKE WILL RESULT IN
PATCHY FOG. A LOW PRESSURE SYSTEM AND FRONTAL BOUNDARY WILL EFFECT
THE REGION WEDNESDAY THROUGH FRIDAY...HOWEVER...WINDS SHOULD REMAIN
LIGHT AND GENERALLY LESS THAN 15 KNOTS. HIGH PRESSURE BUILDS IN FOR
MUCH OF THE WEEKEND ALLOWING WINDS TO REMAIN LIGHT AND VARIABLE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...KC
MARINE...KC/TITUS
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1052 AM CDT TUE JUL 16 2013
.UPDATE...
MORNING FORECAST UPDATE.
&&
.DISCUSSION...
AREA RADAR ARE SHOWING AT LEAST WIDELY SCATTERED SHOWERS AND A
FEW THUNDERSTORMS PUSHING INTO THE COASTAL COUNTIES THIS MORNING.
VIS SATELLITE NOT SHOWING AS MUCH CLOUD COVER AS YESTERDAY SO
THINK MAX TEMPS IN THE UPPER 80S TO LOW 90S LOOKS ON TRACK. UPPER
LEVEL LOW NOW LOCATED OVER NEW MEX AND UPPER LEVEL RIDGE OVER OHIO
VALLEY WILL SUPPORT DEEP SE FLOW OVER THE AREA WITH DEEP TROPICAL
MOISTURE COMING INTO THE REGION ON GOES SOUNDER DATA. GIVEN
CURRENT COVERAGE HAD TO DECREASE POPS SOME BUT LEFT 60 POPS THIS
MORNING WHERE IT WILL MOST LIKELY RAIN NEXT 3 HRS BASED ON RADAR
TRENDS. LAST COUPLE OF HRRR RUNS AND 00Z/06Z WRF RUNS SHOW MORE
WIDESPREAD SCATTERED ACTIVITY DURING THE AFTERNOON AS BOUNDARY
LAYER HEATS UP. THINK 60 POPS OVER MUCH OF THE AREA WILL COVER THE
RAIN CHANCES FOR THE AFTERNOON. ACTIVITY SHOULD DISSIPATE 00-03Z
SO ADJUSTED POPS DOWN SOME FOR THE OVERNIGHT. DO EXPECT ANOTHER
ROUND OF ACTIVITY TOMORROW SO SHOULD SEE POPS INCREASE AGAIN WED
MORNING/AFTERNOON.
MAIN THREATS FROM ANY OF THE STRONGER STORMS WILL BE LOCALLY
HEAVY RAIN...LIGHTNING AND GUSTY WINDS. MOST OF THE ACTIVITY WILL
BE SHOWERS BUT AGAIN A FEW STRONG STORMS COULD OCCUR AS ATMOSPHERE
BECOMES MORE UNSTABLE WITH DAYTIME HEATING. RAIN RATES IN MOST
SHOWERS WILL BE A HALF INCH TO AN INCH AN HOUR BUT THE STRONGER
STORMS COULD PRODUCE A SOLID 1-2 INCHES VERY QUICKLY.
39
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 91 73 91 73 92 / 60 40 50 20 20
HOUSTON (IAH) 89 74 90 75 92 / 60 40 50 20 20
GALVESTON (GLS) 87 80 90 81 90 / 60 40 60 30 30
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 7 PM CDT THIS EVENING
FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...39
AVIATION/MARINE...33
AREA FORECAST DISCUSSION
NWS TUCSON AZ
902 AM MST TUE JUL 16 2013
.SYNOPSIS...A WEATHER SYSTEM FROM THE PLAINS STATES WILL MOVE WEST
AND CONTINUE TO BRING PERIODS OF HEAVY RAIN...ESPECIALLY TO AREAS
NEAR AND WEST OF TUCSON TROUGH TONIGHT. THIS SYSTEM WILL THEN
SETTLE OVER NORTHERN MEXICO FOR THE REST OF THE WEEK. THIS WILL KEEP
A MOIST SOUTHEAST FLOW ALOFT...THUS KEEPING THE CHANCES FOR
AFTERNOON AND EVENING THUNDERSTORMS.
&&
.DISCUSSION...LET US BEGIN THIS MORNING WITH A BRIEF RECAP OF THE
PRECIP FROM YESTERDAY THROUGH OVERNIGHT HOURS. Q2 PRECIPITATION
ANALYSIS...WHICH COMBINES RADAR ESTIMATES WITH REAL
OBSERVATIONS...SUGGESTS WIDESPREAD RAINFALL TOTALS OF 0.75 TO 2
INCHES IN THE LAST 48 HOURS BASICALLY FROM AROUND TUCSON EAST. SOME
LOCATIONS HAVE HAD OVER 4 INCHES OF RAIN IN THE LAST 48
HOURS...INCLUDING MT. LEMMON.
GIVEN THE ANTECEDENT CONDITIONS IN PLACE...WE ARE CONCERNED THAT
FLASH FLOODING WILL BE POSSIBLE TODAY BUT IT MAY TAKE LESS RAINFALL
THAN NORMAL TO PRODUCE RUNOFF IN SEVERAL AREAS.
CURRENT RADAR IMAGERY SHOWS A LINE OF WEAK ECHOS STRETCHING FROM
TOMBSTONE TO THE NORTHWEST INTO SOUTHWEST PINAL COUNTY. THE LATEST
HRRR AND THE UOFA WRF NAM BOTH SEEM TO HANDLE THE LIGHT PRECIP WELL.
THE BIG QUESTION IS HOW WILL TODAY EVOLVE. WILL THE HIGH MOISTURE
CONTENT...SATELLITE ESTIMATED PRECIP WATER VALUES OF 1.6 INCHES PLUS
ACROSS ALL OF SE ARIZONA...AND CLOUD COVER BE TOO MOIST AND LIMIT
THE CONVECTIVE POTENTIAL TODAY OR WILL THE APPROACHING UPPER TROUGH
PROVIDE ENOUGH LIFT TO OVERCOME THE LACK OF HEATING. THE UPPER LOW
IS STILL TRACKING ALONG AS EXPECTED AND SHOULD PUSH INTO NEW MEXICO
TODAY. THE HI RES MODELS DO RESPOND TO THE APPROACHING LOW AND SHOW
MORE ACTIVITY THROUGH THE DAY...BUT THERE IS SOME INCONSISTENCY OVER
THE FAVORED AREAS. THE HRRR SHOWS A FAIRLY WIDESPREAD MODERATE
PRECIP EVENT WITH A FEW EMBEDDED HEAVY PRECIP CORES...WILE THE NAM
WRF DATA FOCUSES THE ACTIONS ACROSS PIMA AND PINAL COUNTIES GIVING
THE EASTERN ZONES A BREAK.
GIVEN THE WET PATTERN IN PLACE WITH THE UPPER TROUGH STILL HEADING
THIS DIRECTION...I FAVOR A MORE WIDESPREAD EVENT TODAY. EITHER
WAY...BOTH MODELS SUGGEST THE ACTIVITY WILL DIMINISH AFTER 00Z TO
02Z. THAT ALSO SEEMS REASONABLE.
&&
.CLIMATE...IN CLIMATE NEWS...DOUGLAS AIRPORT HAS RECEIVED 7.85
INCHES OF RAIN SO FAR THIS MONTH. THIS MAKES JULY THE WETTEST MONTH
ON RECORD...DATING BACK TO 1948. THE PREVIOUS WETTEST MONTH WAS
AUGUST 1959. WE ARE ONLY TWO WEEKS INTO JULY SO HITTING 8 INCHES
THIS MONTH IS WELL WITHIN THE REALM OF POSSIBILITY.
&&
.AVIATION...SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL
OCCUR INTO THIS EVENING. PRECIP WILL DECREASE IN COVERAGE AFTER
ABOUT 17/03Z WITH ONLY ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS LATE TONIGHT THRU WEDNESDAY MORNING. AT THIS TIME
APPEARS THAT KTUS AND KOLS HAVE THE BEST CHANCE OF TSRA/SHRA INTO
THIS EVENING WITH LESSER CHANCES FOR KDUG. WIND GUSTS TO 50-60 KTS
WILL BE POSSIBLE WITH THE STRONGER TSRA. OTHERWISE...CLOUD DECKS
GENERALLY 8-12K FT AGL AND SURFACE WIND MOSTLY LESS THAN 10 KTS THRU
WEDNESDAY MORNING OR 17/18Z. AVIATION DISCUSSION NOT UPDATED FOR TAF
AMENDMENTS.
&&
.FIRE WEATHER...A LOW PRESSURE SYSTEM OVER THE TEXAS PANHANDLE THIS
MORNING WILL MOVE SOUTHWESTWARD INTO NORTHERN SONORA BY MIDDAY
THURSDAY. THIS SYSTEM IN COMBINATION WITH AMPLE MOISTURE WILL
PROVIDE SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS INTO THIS
EVENING. THE POTENTIAL EXISTS FOR HEAVY RAINFALL INTO THIS EVENING.
THEREAFTER...SOMEWHAT LESS COVERAGE OF RAINFALL IS EXPECTED STARTING
WEDNESDAY. HOWEVER...ADEQUATE MOISTURE WILL BRING SCATTERED SHOWERS
AND THUNDERSTORMS TO THE AREA INTO THIS WEEKEND.
&&
.PREV DISCUSSION...WATER VAPOR IMAGERY DEPICTS THE UPPER LOW TO BE
ON TRACK WITH MODEL RUNS FROM LAST FEW DAYS. LOW IS SPINNING OVER
TEXAS PANHANDLE AND MOVING WEST...WITH THE LATEST BLENDED TOTAL
PRECIPITABLE WATER IMAGERY SHOWING PW`S IN EXCESS OF 1.5 INCHES
ACROSS MUCH OF SOUTHEAST ARIZONA AND VALUES NEAR 1.7 INCHES ACROSS
PORTIONS OF GRAHAM AND COCHISE COUNTIES. LATEST IR SATELLITE IMAGERY
SHOWS EXTENSIVE CLOUDINESS COVERING MUCH OF EASTERN ARIZONA WITH THE
CLOUDS TAPERING OFF FARTHER WEST ACROSS WESTERN ARIZONA.
RECENT RADAR IMAGERY IS DETECTING SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS THAT GENERALLY EXTEND FROM THE NORTHEAST PORTION OF MY
FORECAST AREA...MAINLY FROM EASTERN PINAL COUNTY THROUGH NORTHERN
GREENLEE COUNTY AND SOUTHWARD ACROSS MUCH OF GRAHAM AND COCHISE
COUNTIES...WITH THE ACTIVITY ALSO WESTWARD INTO EXTREME EASTERN
PORTIONS OF PIMA COUNTY. THE HEAVIEST RAIN OF LATE HAS BEEN FOCUSED
OVER THE CATALINA MOUNTAINS OF NORTHEAST PIMA COUNTY WHERE A SMALL
STREAM FLOOD ADVISORY CONTINUES FOR MUCH OF EASTERN PIMA COUNTY...
WHICH INCLUDES THE SANTA CATALINA MOUNTAINS AS WELL AS THE ENTIRE
TUCSON METRO AREA THROUGH 245 AM MST.
MODELS INDICATE THAT THE UPPER LOW WILL CONTINUE TO MOVE SOUTHWEST
TODAY...REACHING SOUTHEAST NEW MEXICO BY LATE THIS EVENING AND
WEAKEN IN THE PROCESS. MODELS SEEM TO SUGGEST THAT AS THIS OCCURS...
THE BAND OF PRECIPITATION ON THE WESTERN FLANK OF THE LOW WILL SHIFT
A TAD WESTWARD TODAY...WHILE AREAS TO THE EAST MAY SEE A SLIGHT
DOWNWARD TREND IN SHOWER AND THUNDERSTORM ACTIVITY...MAINLY LATE IN
THE DAY. INHERITED FLASH FLOOD WATCH AND ITS TIMING SEEMS TO BE ON
TRACK WITH IT ENDING EARLY THIS EVENING. HOWEVER...THIS IS SOMETHING
THE DAY SHIFT WILL HAVE A BETTER HANDLE ON AS THIS SYSTEM EVOLVES
THROUGHOUT THE DAY.
MADE SOME TWEAKS TO THE POP FORECAST BASED ON THE LATEST MODEL
DATA...BUT CHANGES WERE FAIRLY MINOR. STILL LOOKING AT SLIGHT
CHANGES POPS THIS MORNING FOR THE FAR WESTERN PORTIONS OF THE
FORECAST AREA...SPECIFICALLY WESTERN PIMA COUNTY...WITH A STEEP POP
GRADIENT AS YOU GO EAST...WITH POPS IN THE LIKELY TO CATEGORICAL
RANGE FOR THE EASTERN ZONES. SIMILAR CHANCES THIS AFTERNOON...BUT
THE SHOWERS AND STORMS WILL PUSH A BIT FARTHER WEST LATE THIS
AFTERNOON AND INTO THE EARLY EVENING HOURS.
BEYOND TODAY MODELS SHOW THIS LOW TRAVERSING NORTHERN MEXICO WHICH
WILL PROVIDE A SOUTHEAST FLOW ACROSS THE DESERT SOUTHWEST. AS A
RESULT...EXPECT SCATTERED SHOWERS AND THUNDERSTORMS MAINLY EACH
AFTERNOON AND EVENING THROUGH NEXT MONDAY.
HIGH TEMPERATURES GENERALLY 6 TO 8 DEGS BELOW NORMAL TODAY...THEN 3
TO 5 DEGS BELOW NORMAL THEREAFTER. LOW TEMPERATURES THROUGHOUT THE
FORECAST PERIOD WILL BE NEAR NORMAL.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH THIS EVENING FOR AZZ507>514.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
PUBLIC...BROST
AVIATION/FIRE WEATHER...FRANCIS
AREA FORECAST DISCUSSION
NWS NEW YORK NY
450 PM EDT TUE JUL 16 2013
.SYNOPSIS...
HOT AND HUMID WEATHER WILL CONTINUE THROUGH THE END OF THE WEEK
WITH WEAK HIGH PRESSURE REMAINING ACROSS THE REGION THROUGH
WEDNESDAY NIGHT. A WEAK TROUGH OF LOW PRESSURE WILL DEVELOP ACROSS
THE AREA FOR THE REST OF THE WEEK. A COLD FRONT APPROACHES ON
SATURDAY AND MOVES SOUTH OF THE REGION ON SUNDAY AS HIGH PRESSURE
RETURNS FOR EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
WEAK HIGH PRESSURE ACROSS REGION WITH SHORTWAVE MOVING THROUGH NEW
ENGLAND THIS EVENING. UPPER LEVEL RIDGE STAYS ANCHORED TO OUR WEST.
HEAT AND HUMIDITY STILL IN PLACE WITH INCREASING MOISTURE CONTENT
WITHIN BOUNDARY LAYER. SEA BREEZE MORE SUPPRESSED TODAY SIMILAR TO
YESTERDAY. A SHORTWAVE MOVING ACROSS NEW ENGLAND THIS EVENING WILL
ALLOW FOR A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS AHEAD AND
ALONG IT. SOME MESO MODELS SUCH AS THE HRRR AND WRF NMM ARE
INDICATING THIS POSSIBILITY. OTHERWISE...DRY AND HUMID WEATHER
CONTINUES TONIGHT. LOWS WERE PREFERRED WITH WARMER
GUIDANCE...KEEPING TEMPERATURES IN THE 70S FOR MUCH OF THE AREA
TONIGHT AND UPPER 60S FOR INTERIOR AND RURAL SECTIONS.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
UPPER LEVEL RIDGE TO OUR WEST BEGINS TO SLOWLY FLATTEN WITH HIGH
PRESSURE AT THE SURFACE CONTINUING TO WEAKEN. A SURFACE TROUGH
DEVELOPS ACROSS THE AREA WEDNESDAY...WITH A BETTER SOUTHERLY FLOW
DEVELOPING ACROSS COASTAL SECTIONS. SO A BETTER CHANCE FOR SEA
BREEZES DURING THE AFTERNOON FOR AT LEAST IMMEDIATE COASTAL
SECTIONS. FLOW TURNS MORE SOUTHWEST WEDNESDAY NIGHT. POSSIBLE
SHOWER OR THUNDERSTORM ACROSS THE INTERIOR BUT NOT ENOUGH
CONFIDENCE TO INSERT IN FORECAST.
HIGHS WILL BE WELL INTO THE 90S WITH DEWPOINTS HIGHEST ALONG THE
URBAN CORRIDOR AND THE LOWER HUDSON VALLEY AS WELL AS INTERIOR
SOUTHERN CONNECTICUT. UPPER 80S TO LOWER 90S MAX TEMPS TOWARDS THE
COASTLINE IN COMBINATION WITH THE DEWPOINT WILL KEEP HEAT INDICES
AT LEAST A FEW DEGREES BELOW 100 DEGREES...THE CRITERION FOR HEAT
ADVISORY OUTSIDE OF NYC. HOWEVER...URBAN NORTHEAST NEW JERSEY AS
WELL AS NEW YORK CITY...THE LOWER HUDSON VALLEY...AND INTERIOR
SOUTHERN CONNECTICUT WILL BE APPROACHING 100 DEGREES FOR HEAT
INDICES SO HEAT ADVISORIES EXTENDED THROUGH EARLY WEDNESDAY
EVENING FOR THESE LOCATIONS. THERE IS SOME UNCERTAINTY DEPENDING
ON DAYTIME MIXING...WHICH IS FORECAST TO BE UP TO AROUND 850 MB
AGAIN. HOWEVER...MOISTURE IS FORECAST TO INCREASE RELATIVE TO
TODAY AND THIS MAKES SENSE DUE TO A GREATER SOUTHERLY SYNOPTIC
FLOW AND LESS SYNOPTIC NORTHERLY FLOW.
FOR WEDNESDAY NIGHT...SIMILAR TEMPS TO PREVIOUS NIGHT WITH DRY
WEATHER IN PLACE.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
DEEP LAYERED RIDGING WILL REMAIN OVER THE EASTERN CONUS THROUGH
FRIDAY. BY FRIDAY NIGHT...THERE IS EXCELLENT AGREEMENT AMONG THE
OPERATIONAL AND ENSEMBLE GUIDANCE OF THE RIDGE BREAKING DOWN AND
SHIFTING OFFSHORE AS UPPER LEVEL HEIGHTS BEGIN TO FALL AHEAD OF A
TROUGHING BUILDING INTO THE NE US. THIS TROUGH SENDS A COLD FRONT
THROUGH THE AREA SATURDAY/SATURDAY NIGHT.
HOT AND HUMID CONDITIONS WILL CONTINUE INTO SATURDAY. H85 TEMPS ARE
FORECAST TO RANGE FROM 18C TO 20C ON THURSDAY AND FRIDAY HELPING TO
MAKE THESE DAYS THE HOTTEST OF THE EXTENDED PERIOD. HEAT ADVISORY
HAS BEEN EXTENDED UNTIL 8PM THURSDAY FOR NEW YORK CITY. FOR LOWER
HUDSON VALLEY...NE NJ...AND INTERIOR CT...IT IS POSSIBLE HEAT
ADVISORY CRITERIA WILL BE MET THURSDAY BUT CONFIDENCE IS LOW AT THIS
TIME. ONE POSSIBLE CAVEAT IS HOW MUCH DRIER AIR MIXES DOWN. SIMILAR
CONDITIONS/CONCERNS EXIST ON FRIDAY SO WILL NEED TO CONTINUE TO
MONITOR TRENDS. WITH A SURFACE TROUGH AND HIGH AMOUNTS OF
INSTABILITY THURS AND FRI...A SHOWER OR THUNDERSTORM CANNOT BE RULED
OUT. THESE WILL LIKELY BE PULSE IN NATURE AS SHEAR IS MINIMAL.
COLD FRONT THEN APPROACHES SATURDAY BRINGING MUCH BETTER CHANCES FOR
SHOWERS AND STORMS. WITH HEIGHT FALLS OCCURRING ALOFT AND BETTER
SYNOPTIC LIFT...THE CHANCES FOR SHOWERS AND STORMS INCREASE.
INGREDIENTS MAY BE PRESENT TO PROMOTE SEVERE WEATHER SAT WITH THE
FRONT. PRIMARY THREATS AT THIS TIME APPEAR TO BE DAMAGING WINDS. ANY
STORM MAY ALSO PRODUCE HEAVY RAINFALL AS PWATS APPROACH 2 INCHES
SATURDAY.
THE FRONT SHOULD MOVE SOUTH OF THE AREA SUNDAY. HOWEVER...12Z GFS
DOES SLOW ITS PROGRESSION WITH A WAVE DEVELOPING ALONG IT. THE
LATEST 12Z ECMWF AND 12Z CMC DO NOT DEPICT THIS SCENARIO...BUT DO
HINT AT A SLIGHTLY SLOWER PROGRESSION SOUTHWARD.
THEREFORE...LINGERED CHANCE POPS MAINLY ACROSS SOUTHERN ZONES
SUNDAY.
A RETURN TO MORE SEASONABLE CONDITIONS EXPECTED FOR EARLY NEXT WEEK
AS HIGH PRESSURE BUILDS INTO THE AREA.
&&
.AVIATION /21Z TUESDAY THROUGH SUNDAY/...
CONCERN IS WHETHER SEA BREEZE CAN MAKE IT THROUGH KJFK OVER THE
NEXT COUPLE OF HOURS. SEA BREEZE NOTICEABLE ON TJFK RADAR JUST
SOUTH OF THE TERMINAL AND ALONG THE BARRIER ISLANDS. POTENTIAL
EXISTS FOR THE SEA BREEZE TO COME THROUGH BETWEEN 23-24Z AS TEMPS
DECREASE...AND THEN WINDS WOULD SHIFT TO THE SOUTH. BY
02-03Z...WINDS WILL BE VRB AT 5 KT OR LESS.
OTHERWISE...HIGH PRES REMAINS OVER THE AREA.
GENERALLY NNE TO NNW FLOW AT 8-12 KT WITH OCNL GUSTS OF 16-18 KT
OVER THE TERMINALS. WINDS BECOME VRB AT 5 KT OR LESS AFT 02Z...AND
THEN NE TO SE WINDS INCREASE TO 5-7 KT AFT 14Z WEDNESDAY.
VFR THROUGH THE TAF PERIOD.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: LOW CONFIDENCE ON SEA BREEZE THIS EVENING.
BEST TIMING WOULD BE BTWN 23-24Z...IF THE SEA BREEZE DOES MOVE
THROUGH THE TERMINAL. HIGH CONFIDENCE WINDS TO THE RIGHT OF 310
TRUE OTHERWISE.
KLGA FCSTER COMMENTS: HIGH CONFIDENCE WINDS TO THE RIGHT OF 310
TRUE THROUGH THIS EVENING. VERY LOW CHANCE OF SEA BREEZE DURING
THE LATE AFTERNOON/EARLY EVENING HOURS.
KEWR FCSTER COMMENTS: HIGH CONFIDENCE WINDS TO THE RIGHT OF 310
TRUE THROUGH THIS EVENING. VERY LOW CHANCE OF SEA BREEZE DURING
THE LATE AFTERNOON/EARLY EVENING HOURS.
KTEB FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
KHPN FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
KISP FCSTER COMMENTS: HIGH CONFIDENCE WINDS TO THE RIGHT OF 310
TRUE THROUGH THIS AFTERNOON. LOW CHANCE SEA BREEZE IMPACTS
KISP...BUT IF IT DOES...IT WOULD OCCUR BETWEEN 20-22Z.
.OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY...
.WEDNESDAY-WEDNESDAY NIGHT...VFR.
.THURSDAY AND FRIDAY NIGHT...VFR. SLIGHT CHANCE SHRA/TSTM MAINLY
N AND W OF NYC DURING THE AFTERNOON/EVENING.
.SATURDAY...MAINLY VFR...BUT THE POTENTIAL LIES FOR WITH MVFR OR
LOWER CONDS IN STRONG TO SEVERE CONVECTION.
.SUNDAY...IMPROVING CONDS.
&&
.MARINE...
SUB SCA CONDITIONS ARE EXPECTED TO PREVAIL THROUGH WEDNESDAY NIGHT WITH
A WEAK PRESSURE GRADIENT IN PLACE.
A 15-20KT SW FLOW DEVELOPS OVER THE WATERS WITH GUSTS LIKELY
APPROACHING SCA LEVELS FRIDAY INTO SATURDAY. SEAS WILL ALSO BUILD TO
SCA LEVELS DURING THIS TIME. SUNDAY INTO MONDAY...WINDS SHOULD
REMAIN BELOW SCA LEVELS WITH MARGINAL SCA SEAS.
&&
.HYDROLOGY...
DRY CONDITIONS ARE EXPECTED THROUGH WEDNESDAY NIGHT.
A MOIST AIRMASS OVER THE AREA THURSDAY INTO FRIDAY BRINGS THE
POTENTIAL FOR HEAVY DOWNPOURS. HOWEVER...THUNDERSTORMS SHOULD REMAIN
ISOLATED LIMITING ANY FLASH FLOODING POTENTIAL. THE CHANCE FOR FLASH
FLOODING INCREASES ON SATURDAY WITH BETTER THUNDERSTORM COVERAGE AND
PRECIPITABLE WATERS INCREASING TO AROUND 2 INCHES.
&&
.CLIMATE...
TUESDAY JULY 16 2013 RECORD MAXIMUM TEMPERATURES
SITE RECORD FORECAST HIGH
BRIDGEPORT 94 (1983, 1952) 95
ISLIP 93 (1999) 95
LAGUARDIA 97 (1980) 97
KENNEDY 100 (1983) 95
CENTRAL PARK 99 (1980) 96
NEWARK 101 (1988) 97
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...HEAT ADVISORY UNTIL 8 PM EDT WEDNESDAY FOR CTZ005>008.
HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR CTZ009>012.
NY...HEAT ADVISORY UNTIL 8 PM EDT WEDNESDAY FOR NYZ067>071.
HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NYZ078-080-177-
179.
HEAT ADVISORY UNTIL 8 PM EDT THURSDAY FOR NYZ072>075-176-178.
NJ...HEAT ADVISORY UNTIL 8 PM EDT WEDNESDAY FOR NJZ006-104-106-108.
HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NJZ004-103-105-
107.
MARINE...NONE.
&&
$$
SYNOPSIS...JM/DS
NEAR TERM...JM
SHORT TERM...JM
LONG TERM...DS
AVIATION...MPS
MARINE...JM/DS
HYDROLOGY...JM/DS
CLIMATE...
AREA FORECAST DISCUSSION
NWS TAUNTON MA
435 PM EDT TUE JUL 16 2013
.SYNOPSIS...
HOT AND HUMID WEATHER WILL CONTINUE THIS WEEK WITH ONLY WIDELY
SCATTERED SHOWERS OR THUNDERSTORMS ON WED. CHANCES FOR SHOWERS
AND THUNDERSTORMS WILL INCREASE THU...FRI AND ESPECIALLY SAT AS A
COLD FRONT APPROACHES FROM THE GREAT LAKES. RELIEF FROM THE HEAT
AND HUMIDITY WILL ARRIVE ON SUNDAY BEHIND A STRONG COLD FRONT AND
LAST THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
AS OF LATE THIS AFTERNOON THERE WERE ONLY A FEW SHOWERS ALONG THE
SEACOAST OF NH. SATELLITE SHOWED THE CUMULUS FIELD ALREADY
BEGINNING TO ERODE...SO DO NOT EXPECT ANYTHING MORE THAN AN
ISOLATED SHOWER IN NORTHEAST MA OR SOUTHERN NH BEFORE SUNSET.
DIURNAL DEWPOINT RISE AND WARM TEMPERATURES WILL LEAD TO ANOTHER
WARM HUMID NIGHT TONIGHT WITH MANY LOCATIONS REMAINING IN THE
UPPER 60S TO LOWER 70S. THERE WAS LITTLE IN THE WAY OF FOG
OVERNIGHT LAST NIGHT AND WITHOUT ONSHORE FLOW ACROSS THE AREA...
AM NOT EXPECTING MORE THAN A TOUCH OF FOG OVERNIGHT.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
WED WILL BE SIMILAR TO TODAY...WITH A MOSTLY CLEAR START AND
TEMPERATURES RAPIDLY CLIMBING INTO THE LOWER TO MID 90S.
TEMPERATURES WILL BE A COUPLE OF DEGREES WARMER AND DEWPOINTS WILL
BE A DEGREE OR TWO HIGHER...WHICH WILL LEAD TO HEAT INDICES
REACHING 98-102 OVER MOST OF SOUTHERN NEW ENGLAND...INCLUDING
SOUTHERN NH...WITH THE ONLY EXCEPTIONS BEING CAPE COD AND THE
ISLANDS. THUS HAVE ISSUED A HEAT ADVISORY FOR MOST OF THE REGION
FOR WED AFTERNOON AND EARLY EVENING.
WINDS WILL STILL BE LIGHT...BUT SHOULD TURN TO A SOUTHERLY
DIRECTION. ALTHOUGH HIGHS REACHED 90 ON BLOCK ISLAND TODAY...WITH
LIGHT SOUTHERLY WINDS EXPECTED OFF OF THE COOLER WATERS WED...HAVE
ONLY FORECAST MID 80S THERE...IT COULD POTENTIALLY BE COOLER THAN
THAT.
THERE IS A CHANCE OF AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS
ON WED...MAINLY IN SOUTHERN NH AND NORTHERN MA...AS LOW PRESSURE
MOVES ACROSS SOUTHERN QUEBEC AND A TROUGH OF LOW PRESSURE PASSES
ACROSS NEW ENGLAND. UPPER LEVEL HIGH PRES RIDGE STILL IN CONTROL
THOUGH WITH CAP AROUND H7 AND UNFAVORABLE MID LEVEL LAPSE RATES.
SB CAPE VALUES LOOK TO BE A BIT HIGHER THANKS TO THE INCREASING
MOISTURE WITHIN THE COLUMN...AVERAGING ABOUT 1500-2000 J/KG.
THEREFORE...WENT WITH 25 TO 35 PCT CHANCE IN NORTHEAST MA/SOUTHERN
NH AND 20 PCT FARTHER TO THE SOUTH INTO NORTHERN CT/RI/SOUTHEAST
MA.
WEDNESDAY EVENING...ANY CONVECTION WILL DIMINISH AGAIN BY SUNSET.
ANOTHER WARM AND MUGGY NIGHT WITH CLEAR TO PARTLY CLOUDY SKIES IS
EXPECTED. PERHAPS A LITTLE MORE PATCHY FOG AS THE AIR MASS GETS
EVEN MORE HUMID. LOWS MAINLY UPPER 60S TO MID 70S.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
HEADLINES...
* HOT/HUMID THU INTO SAT WITH SCATTERED T-STORMS
* SEVERE STORMS POSSIBLE AHEAD OF A COLD FRONT SAT
* SEASONABLE AND DRY SUNDAY INTO THE BEGINNING OF NEXT WEEK
DETAILS...
NOT MUCH CHANGE IN OUR FORECAST THINKING FROM PREVIOUS SHIFTS.
MODELS REMAIN IN GOOD OVERALL AGREEMENT SHIFTING H5 HIGH SOUTH
AND WEST TOWARDS THE FOUR-CORNERS REGION ALLOWING FOR FALLING
HEIGHTS ACROSS NEW ENGLAND. THIS RESULTS IN THE RETURN OF THE
NORTHERN STREAM AS DOMINANT INFLUENCE AND SUBSEQUENTLY A MORE
ACTIVE PATTERN.
THURSDAY...
MODELS KEY ON LEE TROUGH BECOMING FOCUS FOR SCATTERED AFTERNOON
CONVECTION. SURFACE-BASED CAPES REACH 1500 J/KG WITH DECENT MID
LEVEL LAPSE RATES AROUND 6C/KM...BUT 0-6KM SHEAR IS MARGINAL AT
BEST. STILL NEED TO OVERCOME RATHER WARM MID LEVEL TEMPERATURES...
SO NOT CONFIDENT THAT STORM COVERAGE WILL BE ALL THAT GREAT. KEPT
CHANCE POPS FOR SCATTERED AFTERNOON THUNDERSTORMS WITH CONTINUED
MENTION OF HEAVY RAIN.
HIGH CAPE ENVIRONMENT FAVORS STRONG TO ISOLATED SEVERE STORMS...
BUT OVERALL SEVERE THREAT APPEARS TO BE LIMITED. PRECIPITABLE
WATER VALUES APPROACHING 2 INCHES...WHICH IS AROUND +2 STANDARD
DEVIATIONS...MEANS POTENTIAL FOR HEAVY RAINFALL AND ISOLATED
FLOODING IN STORMS.
HIGHS IN 90S AWAY FROM S COAST COMBINED WITH DEW POINTS IN LOWER
70S WILL ONCE AGAIN YIELD HEAT INDICES AROUND 100.
FRIDAY...
FLOW ALOFT BECOMES FLATTER WHICH SHOULD ALLOW ANY UPSTREAM
ACTIVITY TO PASS TO OUR N. HOWEVER WE REMAIN IN UNSTABLE AIRMASS
WITH BETTER CONVECTIVE POTENTIAL THAN THU. MODELS SHOW SURFACE
BASED CAPES 2000-3000 J/KG AND MID LEVEL LAPSE RATES OVER 6C/KM.
AXIS OF GREATEST 0-6KM SHEAR REMAINS ACROSS NORTHERN NEW ENGLAND
BUT SW NH AND NORTHERN MA ARE ON PERHIPHERY OF THIS AXIS WITH
VALUES OF 30-35KT. IN ADDITION WE ARE IN FAVORABLE RR QUAD OF
UPPER JET. ONLY LIMITING FACTOR APPEARS TO BE WARM MID LEVEL TEMPS
/+11C AT 700 MB/ BUT COLDER AIR ALOFT SHOULD BE ABLE TO
COMPENSATE.
EXPECT SCATTERED STORMS TO DEVELOP FRI AFTERNOON ACROSS MUCH OF
SOUTHERN NEW ENGLAND...ASIDE FROM IMMEDIATE S COAST WHICH WILL BE
MORE STABLE DUE TO SW FLOW. SEVERE POTENTIAL IS SOMEWHAT BETTER
THAN THU WITH BETTER POSSIBILITY OF DAMAGING WINDS DUE TO BOWING
SEGMENTS OR LINES. ALSO HAVE CONTINUED POTENTIAL FOR HEAVY
RAINFALL AND ISOLATED FLOODING.
INCREASING SW FLOW WILL RESULT IN WARMER DAY THAN THU. HIGHS
SHOULD TOP OUT IN LOW-MID 90S /GIVEN MODEL 2M TEMPERATURES/
COMBINED WITH DEW POINTS IN LOW-MID 70S SHOULD YIELD HEAT INDICES
OF 100-105. NOT CONFIDENT ENOUGH TO ISSUE EXCESSIVE HEAT WATCH BUT
WE MAY NEED TO DO SO IF THIS BECOMES MORE CERTAIN.
SATURDAY...
BEST POTENTIAL FOR ORGANIZED CONVECTION AS STRONG COLD FRONT
APPROACHES FROM GREAT LAKES. SOME QUESTION AS TO WHETHER OR NOT
ANY EARLY MORNING CONVECTION WILL INHIBIT SIGNIFICANT
DESTABILIZATION DURING AFTERNOON. PATTERN SEEMS TO FAVOR AT LEAST
MORNING SHOWERS/STORMS NEAR S COAST...THEN WE SEE A BREAK BEFORE
ADDITIONAL STORMS FIRE DURING AFTERNOON AND EVENING.
NO REAL CHANGE IN THINKING FROM SPC DAY 4 OUTLOOK AND PREVIOUS
DISCUSSION. EXPECTED INSTABILITY COUPLED WITH BULK SOUTHWESTERLY
UNI-DIRECTIONAL SHEAR AROUND 35 KTS FAVORS MULTICELLS AND LINE
ECHO WAVE PATTERNS WITH DAMAGING WINDS MAIN THREAT. ALSO NEED TO
BE AWARE OF CONTINUED FLASH FLOOD POTENTIAL WITH PRECIPITABLE
WATER VALUES NEAR 2 INCHES.
SUNDAY INTO THE EARLY WEEK...
COLD FRONT WILL HEAD OFFSHORE SUN MORNING...PERHAPS NOT UNTIL SUN
AFTERNOON ON CAPE COD. COOLER AND DRIER AIR WILL FOLLOW ON NW
WINDS LATER SUN. FRONT MAY BECOME STATIONARY AS IT RUNS UP INTO
RIDGING OVER WESTERN ATLANTIC. THIS WOULD KEEP US IN NE FLOW
MON/TUE WITH DRY WEATHER ANTICIPATED...ALTHOUGH IT IS POSSIBLE ONE
OR TWO WEAK AREAS OF LOW PRESSURE COULD COME CLOSE ENOUGH TO BRING
AT LEAST SOME CLOUDINESS TO SE NEW ENGLAND.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT-TERM /THROUGH WEDNESDAY NIGHT/...HIGH CONFIDENCE.
VFR THROUGHOUT. SEA-BREEZES ALONG THE SHORES. ISOLATED
SHOWER POSSIBLE THIS EVENING MAINLY NE MA. BETTER CHANCE OF
SHOWERS/TSTMS WED AFTERNOON ESPECIALLY NORTHERN MA/SOUTHERN NH.
LOW PROB OF PATCHY FOG OVERNIGHT TONIGHT AND PERHAPS A LITTLE MORE
COVERAGE ON WED NIGHT.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...THURSDAY THROUGH SUNDAY...
THURSDAY AND FRIDAY...MODERATE CONFIDENCE. IFR IN S COASTAL FOG
EARLY. ISOLATED SHOWERS/TSTMS WITH LOCAL IFR IN AFTERNOON.
SATURDAY...MODERATE CONFIDENCE. IFR IN S COASTAL FOG EARLY.
SCATTERED SHOWERS/TSTMS WITH LOCAL IFR IN AFTERNOON/EVENING.
SUNDAY...MODERATE CONFIDENCE. BECOMING VFR BY AFTERNOON.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
HIGH CONFIDENCE...
WINDS AND SEAS REMAIN BELOW SMALL CRAFT ADVISORY LEVELS THROUGH
WED NIGHT. HIGH PRES REMAINS OVER THE WATERS THROUGH WED. A LOW
PRES APPROACHES THE WATERS AND WEAKENS WED NIGHT. THERE IS A
CHANCE OF SOME REDUCED VSBYS IN FOG IN SOME SPOTS.
OUTLOOK...THURSDAY THROUGH SUNDAY...
THURSDAY AND FRIDAY...HIGH CONFIDENCE.
WEAK GRADIENT WILL RESULT IN SEA BREEZES ALONG E COAST WITH MORE
OF A SW FLOW ALONG S COAST WHERE 20KT GUSTS POSSIBLE. ISOLATED
THUNDERSTORMS POSSIBLE BOTH DAYS NEAR SHORE. EXPECT AREAS OF
NIGHTTIME AND EARLY MORNING FOG AROUND CAPE COD.
SATURDAY...MODERATE CONFIDENCE.
APPROACHING COLD FRONT WILL BRING INCREASING SW FLOW ON ALL WATERS
AS SEAS SLOWLY BUILD ON S COASTAL WATERS. STAYED BELOW WAVE WATCH
MODEL FORECAST OF 6-8 FT AS THIS MODEL IS TYPICALLY OVERDONE IN SW
FLOW DURING SUMMER...SHOULD BE MORE LIKE 4-5 FT AT MOST AND SCA
WILL PROBABLY BE NEEDED OFFSHORE.
AREAS OF NIGHTTIME AND EARLY MORNING FOG SHOULD PERSIST AROUND
CAPE COD.
SCATTERED THUNDERSTORMS POSSIBLE IN TWO ROUNDS...FIRST EARLY SAT
MORNING /PERHAPS NEAR S COAST?/ AND AGAIN TOWARD EVENING INTO SAT
NIGHT AS COLD FRONT PUSHES THROUGH NEW ENGLAND.
SUNDAY...MODERATE CONFIDENCE.
WINDS SHIFT TO NW AND DIMINISH AS COLD FRONT HEADS OFFSHORE BY
AFTERNOON. SEAS SLOWLY DIMINISH AS WELL BUT SHOULD REMAIN AT 5 OR
6 FT SE OF CAPE COD. SHOWERS/THUNDERSTORMS SHOULD LINGER
INITIALLY ON WATERS SE OF NANTUCKET BUT SHOULD BE WELL OFFSHORE BY
EARLY AFTERNOON.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...HEAT ADVISORY FROM 11 AM TO 7 PM EDT WEDNESDAY FOR CTZ002>004.
HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR CTZ002>004.
MA...HEAT ADVISORY FROM 11 AM TO 7 PM EDT WEDNESDAY FOR MAZ002>021-
026.
HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR MAZ010-011-013-
017-018.
NH...HEAT ADVISORY FROM 11 AM TO 7 PM EDT WEDNESDAY FOR NHZ011-012-
015.
RI...HEAT ADVISORY FROM 11 AM TO 7 PM EDT WEDNESDAY FOR RIZ001>007.
HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR RIZ001>004-006.
MARINE...NONE.
&&
$$
SYNOPSIS...JWD/GAF
NEAR TERM...GAF
SHORT TERM...GAF
LONG TERM...JWD
AVIATION...JWD/GAF
MARINE...JWD/GAF
AREA FORECAST DISCUSSION
NWS ALBANY NY
425 PM EDT TUE JUL 16 2013
.SYNOPSIS...
HOT AND HUMID CONDITIONS WILL CONTINUE THROUGH THE REST OF THE WORK
WEEK...AS AN EXPANSIVE AREA OF HIGH PRESSURE ALOFT ENCOMPASSES MUCH
OF THE EASTERN UNITED STATES. IT WILL CONTINUE TO BE MAINLY
DRY...UNTIL THURSDAY WHEN MULTIPLE FRONTAL BOUNDARIES WILL MOVE
ACROSS THE AREA RESULTING IN SCATTERED SHOWERS AND THUNDERSTORMS
INTO THE FIRST HALF OF THE WEEKEND. THE FINAL COLD FRONT LOOKS TO
MOVE THROUGH THE AREA ON SATURDAY BRINGING AND END TO THE HEAT WAVE.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
AS OF 415 PM EDT...ANOTHER HOT AFTERNOON ACROSS THE AREA. ALBANY
AND POUGHKEEPSIE HAVE NOW REACHED 90 DEGREES FOR THE THIRD DAY IN
A ROW MAKING IT ANOTHER OFFICIAL HEAT WAVE...THE SECOND OF THIS
YEAR FOR BOTH LOCATIONS. A NORTHERLY AND OCCASIONALLY GUSTY BREEZE
HAS ALLOWED FOR SOME DEEPER MIXING WHICH HAS RESULTED IN DEWPOINTS
LOWER THAN PREVIOUS DAYS IN THE LOWER TO MID 60S ACROSS MUCH OF
THE AREA. THEREFORE WILL CANCEL THE HEAT ADVISORY FOR EASTERN
ULSTER...DUTCHESS AND SOUTHERN LITCHFIELD COUNTIES SINCE HEAT
INDEX VALUES WILL NOT REACH 100.
AN ISOLATED SHOWER OR TWO POPPED UP EARLIER IN THE SARATOGA REGION
BUT HAVE SINCE DISSIPATED. IT CONTINUES TO BE DIFFICULT TO BREAK THE
STRONG CAP AT 700 MB...SO ANY CONVECTION WILL BE BRIEF AND ISOLATED
AT BEST WITH VERY WEAK FORCING AS WELL. SPC MESOSCALE ANALYSIS FROM
THE RAP SHOWING SBCAPES MAINLY IN THE 1000-1500 J/KG RANGE ACROSS
THE AREA...BUT AGAIN THIS INSTABILITY IS NOT BEING REALIZED DUE TO
THE CAP. IF ANY ISOLATED SHOWERS/T-STORMS POP UP...THEY WILL
DIMINISH AFTER DARK WITH LOSS OF DAYTIME HEATING.
SOME PATCHY FOG WILL BE POSSIBLE AGAIN TONIGHT IN FAVORED RIVER
VALLEYS AND LOCATIONS NEAR BODIES OF WATER. MINIMUM TEMPERATURES
WILL BE ON THE WARM SIDE AGAIN TONIGHT...WITH LOWER TO MID 60S IN
THE HIGHER TERRAIN AND 65-70 ELSEWHERE.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
WEDNESDAY WILL BE ANOTHER HOT AND HUMID DAY ACROSS THE AREA...AS WE
WILL STILL REMAIN UNDER THE INFLUENCE OF THE EXPANSIVE UPPER LEVEL
RIDGE CENTERED OVER THE MIDWEST AND GREAT LAKES. TEMPERATURES SHOULD
BE SIMILAR TO TUESDAY...ALTHOUGH POSSIBLY A FEW DEGREES WARMER DUE
TO LOW LEVEL FLOW BECOMING MORE WESTERLY THAN NORTHERLY. SO
EXPECTING WIDESPREAD LOWER TO MID 90S FOR VALLEY LOCATIONS AND EVEN
UPPER 80S IN THE HIGHER TERRAIN. ALSO DEWPOINTS ARE EXPECTED TO BE
HIGHER THAN TUESDAY AS WELL...WITH HEAT INDEX VALUES AROUND OR
SLIGHTLY EXCEEDING 100 FOR EASTERN ULSTER...DUTCHESS AND SOUTHERN
LITCHFIELD COUNTIES. SO WILL ISSUE A HEAT ADVISORIES FOR THESE
AREAS. HEAT INDICES FORECAST TO BE IN THE MID TO UPPER 90S FOR THE
HUDSON...MOHAWK AND CT VALLEYS SO WILL MENTION POSSIBLE EVENTUAL
HEAT ADVISORY ISSUANCE IF VALUES INCREASE.
CHANCES FOR CONVECTION WILL AGAIN BE VERY LIMITED DUE TO LITTLE IN
THE WAY OF FORCING AND AN EXPECTED MID LEVEL CAP...AS OUR AREA WILL
STILL BE UNDER AN ANTI-CYCLONIC FLOW ALOFT ON THE NORTHEASTERN
PERIPHERY OF THE UPPER RIDGE. SBCAPE VALUES ARE FORECAST TO INCREASE
TO AROUND 1000-2000 J/KG WHICH COULD BE ENOUGH TO PRODUCE BRIEF
THUNDERSTORMS BUT AGAIN COVERAGE IS EXPECTED TO BE ISOLATED AT BEST.
IT WILL CONTINUE TO BE WARM AND MUGGY WEDNESDAY NIGHT WITH ANY
ISOLATED CONVECTION DIMINISHING AFTER DARK.
THURSDAY COULD BE THE FIRST DAY WHICH FEATURES A BETTER CHANCE FOR
GREATER COVERAGE OF CONVECTION...AS THE UPPER LEVEL RIDGE GETS
SUPPRESSED SOUTHWARD TO THE TENNESSEE VALLEY/MID ATLANTIC REGION.
THE RESULT FOR OUR AREA WILL BE HEIGHTS FLATTENING OUT ALOFT AS THE
FLOW PATTERNS CHANGES FROM ANTI-CYCLONIC TO ZONAL. THIS COULD ALLOW
FOR A DISTURBANCE OR TWO EMBEDDED IN THE INCREASING FLOW TO MOVE
THROUGH THE AREA AND PRODUCE SCATTERED CONVECTION MAINLY DURING THE
AFTERNOON AND EVENING. MODELS DEPICTING SBCAPE VALUES AROUND
1500-2500 J/KG WITH 0-6 KM BULK SHEAR MAGNITUDE AROUND 25-35 KT.
WITH LESS OF A CAP EXPECTED AND BETTER FORCING...THIS COULD ALLOW
FOR SOME ORGANIZED CLUSTERS OF CONVECTION TO DEVELOP. SOME OF THE
STORMS COULD BE STRONG DEPENDING ON THE EVENTUAL DEGREE OF
INSTABILITY. TEMPERATURES ON THURSDAY WILL ONLY AGAIN BE HOT WITH
LIKELY ADDITIONAL HEAT ADVISORIES LIKELY. WILL CONTINUE TO MENTION
IN HWO. THE ONLY NEGATING FACTOR TO REACHING SIMILAR TEMPS TO
WEDNESDAY WILL BE HOW MUCH CONVECTION/CLOUD COVER DEVELOPS DURING
THE AFTERNOON.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
BY FRIDAY THE PROCESS WILL BE UNDERWAY FOR THE UPPER RIDGE TO BUILD
MORE RAPIDLY WESTWARD WHILE NORTHERN STREAM UPPER TROUGHING BUILDS
SOUTH OUT OF CANADA INTO EASTERN NORTH AMERICA. THE ASSOCIATED COLD
FRONT IS EXPECTED TO DROP SOUTH IN STAGES EACH AFTERNOON AND EVENING
FRIDAY AND SATURDAY. THE LOW LEVEL THERMAL RIDGE SHOULD BE OVER THE
REGION FRIDAY AFTERNOON WITH PERHAPS THE HOTTEST TEMPERATURES OF
THIS PERIOD OF HEAT. HIGHS SHOULD BE SOLIDLY IN THE 90S...WITH SOME
MID TO UPPER 90S FROM THE CAPITAL DISTRICT AND POINTS SOUTH. HEAT
INDICES COULD EASILY EXCEED 100 IN MANY AREAS FRIDAY.
BASED ON THE MOVEMENT OF THE COLD FRONT...GENERALLY THE NORTHERN
HALF OF OUR FORECAST AREA SHOULD SEE THE BEST COVERAGE OF
THUNDERSTORMS THROUGH FRIDAY NIGHT...BUT ISOLATED THUNDERSTORMS ARE
STILL POSSIBLE IN SOUTHERN AREAS. ON SATURDAY...THE BOUNDARY LAYER
THERMAL GRADIENT WILL MAKE ITS MOVE THROUGH THE REGION AND THE COLD
FRONT SHOULD GET SOUTH OF THE FORECAST AREA BY SATURDAY NIGHT.
SO...HIGHS SATURDAY SHOULD BE IN THE 80S TO AROUND 90 AND THE BEST
COVERAGE OF THUNDERSTORMS SHOULD BE IN THE SOUTHERN HALF OF THE
FORECAST AREA...WITH DECREASING COVERAGE IN NORTHERN AREAS. BASED
ON THE UPPER DYNAMICS...UPPER AND LOW LEVEL JET STRUCTURE...
INSTABILITY...MOISTURE AND FRONTOGENESIS...SEVERE THUNDERSTORMS AND
LOCALIZED FLASH FLOODING ARE POSSIBLE FRIDAY AND SATURDAY.
BY SATURDAY NIGHT AND SUNDAY...ALL AREAS SHOULD DRY OUT AND HIGH
TEMPERATURES SUNDAY SHOULD BE AROUND NORMAL...WITH A NOTICEABLY
DRIER AIRMASS. HIGHS SUNDAY IN THE 70S TO LOWER 80S. THE COOLER AND
DRYER WEATHER...AROUND NORMAL TEMPERATURES SHOULD CONTINUE MONDAY
AND TUESDAY...WITH A LITTLE BIT OF WARMING PERHAPS BEGINNING ON
TUESDAY...DEPENDING ON THE TIMING OF ANOTHER UPPER IMPULSE THAT
COULD BEGIN ITS APPROACH TO OUR REGION FROM THE GREAT LAKES.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
VFR CONDITIONS WILL PREVAIL THROUGH THE REMAINDER OF THE AFTERNOON
WITH HIGH PRESSURE CONTINUING TO DOMINATE THE WEATHER ACROSS THE
REGION. WINDS WILL BE NORTHERLY AND LIGHT GENERALLY LESS THAN 10
KNOTS. A WEAK UPPER DISTURBANCE SLIDING OFF TO THE NORTH COMBINED
WITH DAYTIME HEATING MAY PROMOTE AN ISOLATED SHOWER/THUNDERSTORM
ACROSS NORTHERN AREAS SO HAVE INCLUDED VCSH AT KGFL WITH LITTLE
OPERATIONAL IMPACT EXPECTED. ALL OTHER TAF SITES WILL EXPERIENCE
SCATTERED TO BROKEN FAIR WEATHER CUMULUS DURING THE AFTERNOON HOURS
BETWEEN 5-7 KFT.
CLOUD COVER WILL DISSIPATE WITH LOSS OF DAYTIME HEATING TONIGHT WITH
WINDS BECOMING CALM. HAVE ONLY MENTIONED MVFR VISIBILITIES AT
KGFL...KPOU AND KPSF FOR HAZE/FOG WITH MOIST LOW-LEVELS. IFR MAY BE
POSSIBLE AT KGFL AND KPSF BUT CONFIDENCE REMAINS LOW AS WINDS WILL
BE SLOW TO DECOUPLE THROUGH THE OVERNIGHT...ALLOWING ENOUGH MOISTURE
TO MIX OUT DESPITE THE LOW DEWPOINT DEPRESSIONS.
ANY LINGERING PATCHY HAZE/FOG SHOULD QUICKLY DISSIPATE TOWARDS
SUNRISE TUESDAY GIVING WAY TO ANOTHER DAY OF SCATTERED-BROKEN FAIR
WEATHER CUMULUS AND LIGHT NORTHERLY WINDS AROUND 5-10 KNOTS.
WE ARE STARTING A NEW EXPERIMENTAL FORMAT FOR DISPLAYING THE
EXTENDED PORTION OF THE AVIATION DISCUSSION. THIS FORMAT BREAKS THE
EXTENDED PERIODS INTO 12-HOUR INCREMENTS. IT DOES NOT INCLUDE THE
POSSIBILITY OF IFR/VFR BUT THE POTENTIAL SENSIBLE WEATHER AND
"POTENTIAL" IMPACT THE WEATHER MIGHT CAUSE. WE HAVE OMITTED THE WORD
POTENTIAL TO KEEP THE VERBIAGE SHORTER.
TUESDAY NIGHT: LOW OPERATIONAL IMPACT. PATCHY FOG.
WEDNESDAY: MODERATE OPERATIONAL IMPACT. ISOLATED RAIN
SHOWERS...THUNDERSTORMS.
WEDNESDAY NIGHT: LOW OPERATIONAL IMPACT. NO SIGNIFICANT WEATHER.
THURSDAY: MODERATE OPERATIONAL IMPACT. SCATTERED RAIN
SHOWERS...THUNDERSTORMS.
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. ISOLATED RAIN
SHOWERS...THUNDERSTORMS.
FRIDAY-SATURDAY: MODERATE OPERATIONAL IMPACT. SCATTERED RAIN
SHOWERS...THUNDERSTORMS.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. ISOLATED RAIN
SHOWERS...THUNDERSTORMS.
SUNDAY: NO OPERATIONAL IMPACT. NO SIGNIFICANT WEATHER.
&&
.FIRE WEATHER...
DUE TO SIGNIFICANT RAINFALL THAT HAS OCCURRED OVER THE PAST SEVERAL
WEEKS...THERE CONTINUES TO BE NO FIRE WEATHER RELATED CONCERNS.
DECENT RECOVERY IN LOW LEVEL MOISTURE IS EXPECTED EACH NIGHT WITH
DEW FORMATION. RELATIVE HUMIDITY VALUES WILL REMAIN ELEVATED DURING
THE AFTERNOON...ONLY DROPPING TO BETWEEN 40 AND 55 PERCENT.
EXPANSIVE HIGH PRESSURE AT THE SURFACE AND ALOFT...WILL CONTINUE TO
DOMINATE OVER THE EASTERN UNITED STATES RESULTING IN HOT AND HUMID
CONDITIONS. CHANCES FOR SHOWERS AND THUNDERSTORMS WILL INCREASE BY
THURSDAY AND CONTINUE THROUGH SATURDAY AS MULTIPLE FRONTAL
BOUNDARIES APPROACH AND EVENTUALLY MOVE THROUGH THE REGION.
&&
.HYDROLOGY...
OUTSIDE OF A STRAY SHOWER OR THUNDERSTORM...IT WILL BE MAINLY DRY
THROUGH WEDNESDAY WITH HOT AND HUMID CONDITIONS PERSISTING. THE
OVERALL TREND FOR MAIN STEM RIVERS WILL BE FOR FLOWS TO CONTINUE TO
DECREASE.
THE NEXT CHANCE OF MEASURABLE RAIN FOR MOST AREAS WILL BE THURSDAY
INTO SATURDAY WITH AT LEAST SCATTERED SHOWERS AND THUNDERSTORMS...AS
MULTIPLE FRONTAL BOUNDARIES APPROACH AND MOVE THROUGH THE REGION.
WITH HIGH MOISTURE CONTENT AND HUMIDITY LEVELS...HEAVY RAINFALL WILL
BE POSSIBLE WITH ANY THUNDERSTORMS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.CLIMATE...
TO ACCESS HEAT RELATED CLIMATE DATA INCLUDING HEAT WAVES...NUMBER
90+ DEGREES DAYS AND 100+ DEGREES DAYS...PLEASE VISIT
WWW.WEATHER.GOV/ALY/CLIMATE (ALL LOWER CASE) AND GO TO THE
RECORDS... EXTREMES... PAGE FOR ALBANY.
NUMBER OF 90+ DEGREE DAYS AND RECORD HIGHS...
ALBANY NY...
2013 MAY: 1 DAY
2013 JUNE: 4 DAYS
2013 JULY: 6 DAYS
2012: 13 DAYS
2011: 8 DAYS
2010: 14 DAYS
NORMAL: 10 DAYS
RECORD HIGHS: (DATE BACK TO 1874)
JULY 16: 97 DEGREES 1900
JULY 17: 99 DEGREES 1900
JULY 18: 100 DEGREES 1953
JULY 19: 97 DEGREES 1904
GLENS FALLS NY...
2013 MAY: 1 DAY
2013 JUNE: 2 DAYS
2013 JULY: 2 DAYS
2012: 8 DAYS
RECORD HIGHS: (DATE BACK TO 1949)
JULY 16: 95 DEGREES 1983
JULY 17: 99 DEGREES 1953
JULY 18: 97 DEGREES 1953
JULY 19: 95 DEGREES 1977
POUGHKEEPSIE NY...
2013 MAY: 3 DAY
2013 JUNE: 4 DAYS
2013 JULY: 7 DAYS
2012: 22 DAYS
RECORD HIGHS: (DATE BACK TO 1949)
JULY 16: 103 DEGREES 1995
JULY 17: 98 DEGREES 2006
JULY 18: 100 DEGREES 1991
JULY 19: 102 DEGREES 1991
BENNINGTON VT...
2013 MAY: NONE
2013 JUNE: NONE
2013 JULY: 1 DAY
2012: 7 DAYS
PITTSFIELD MA...
2013 MAY: NONE
2013 JUNE: NONE
2013 JULY: NONE
2012: 3 DAYS
&&
.EQUIPMENT...
KENX NATIONAL WEATHER SERVICE DOPPLER RADAR WILL BE UNAVAILABLE
THROUGH TUESDAY JULY 16 2013. TECHNICIANS CONTINUE TO TROUBLESHOOT
AT THIS TIME. WE EXPECT A FULL RETURN TO SERVICE LATER THIS
EVENING. WE APOLOGIZE FOR THE INCONVENIENCE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...HEAT ADVISORY FROM NOON TO 8 PM EDT WEDNESDAY FOR CTZ013.
NY...HEAT ADVISORY FROM NOON TO 8 PM EDT WEDNESDAY FOR NYZ064>066.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...JPV
NEAR TERM...JPV
SHORT TERM...JPV
LONG TERM...NAS
AVIATION...IRL
FIRE WEATHER...BGM/JPV
HYDROLOGY...BGM/JPV
CLIMATE...WFO ALY
EQUIPMENT...WFO ALY
AREA FORECAST DISCUSSION
NWS NEW YORK NY
400 PM EDT TUE JUL 16 2013
.SYNOPSIS...
HOT AND HUMID WEATHER WILL CONTINUE THROUGH THE END OF THE WEEK
WITH WEAK HIGH PRESSURE REMAINING ACROSS THE REGION THROUGH
WEDNESDAY NIGHT. A WEAK TROUGH OF LOW PRESSURE WILL DEVELOP ACROSS
THE AREA FOR THE REST OF THE WEEK. A COLD FRONT APPROACHES ON
SATURDAY AND MOVES SOUTH OF THE REGION ON SUNDAY AS HIGH PRESSURE
RETURNS FOR EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
WEAK HIGH PRESSURE ACROSS REGION WITH SHORTWAVE MOVING THROUGH NEW
ENGLAND THIS EVENING. UPPER LEVEL RIDGE STAYS ANCHORED TO OUR WEST.
HEAT AND HUMIDITY STILL IN PLACE WITH INCREASING MOISTURE CONTENT
WITHIN BOUNDARY LAYER. SEA BREEZE MORE SUPPRESSED TODAY SIMILAR TO
YESTERDAY. A SHORTWAVE MOVING ACROSS NEW ENGLAND THIS EVENING WILL
ALLOW FOR A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS AHEAD AND
ALONG IT. SOME MESO MODELS SUCH AS THE HRRR AND WRF NMM ARE
INDICATING THIS POSSIBILITY. OTHERWISE...DRY AND HUMID WEATHER
CONTINUES TONIGHT. LOWS WERE PREFERRED WITH WARMER
GUIDANCE...KEEPING TEMPERATURES IN THE 70S FOR MUCH OF THE AREA
TONIGHT AND UPPER 60S FOR INTERIOR AND RURAL SECTIONS.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
UPPER LEVEL RIDGE TO OUR WEST BEGINS TO SLOWLY FLATTEN WITH HIGH
PRESSURE AT THE SURFACE CONTINUING TO WEAKEN. A SURFACE TROUGH
DEVELOPS ACROSS THE AREA WEDNESDAY...WITH A BETTER SOUTHERLY FLOW
DEVELOPING ACROSS COASTAL SECTIONS. SO A BETTER CHANCE FOR SEA
BREEZES DURING THE AFTERNOON FOR AT LEAST IMMEDIATE COASTAL
SECTIONS. FLOW TURNS MORE SOUTHWEST WEDNESDAY NIGHT. POSSIBLE
SHOWER OR THUNDERSTORM ACROSS THE INTERIOR BUT NOT ENOUGH
CONFIDENCE TO INSERT IN FORECAST.
HIGHS WILL BE WELL INTO THE 90S WITH DEWPOINTS HIGHEST ALONG THE
URBAN CORRIDOR AND THE LOWER HUDSON VALLEY AS WELL AS INTERIOR
SOUTHERN CONNECTICUT. UPPER 80S TO LOWER 90S MAX TEMPS TOWARDS THE
COASTLINE IN COMBINATION WITH THE DEWPOINT WILL KEEP HEAT INDICES
AT LEAST A FEW DEGREES BELOW 100 DEGREES...THE CRITERION FOR HEAT
ADVISORY OUTSIDE OF NYC. HOWEVER...URBAN NORTHEAST NEW JERSEY AS
WELL AS NEW YORK CITY...THE LOWER HUDSON VALLEY...AND INTERIOR
SOUTHERN CONNECTICUT WILL BE APPROACHING 100 DEGREES FOR HEAT
INDICES SO HEAT ADVISORIES EXTENDED THROUGH EARLY WEDNESDAY
EVENING FOR THESE LOCATIONS. THERE IS SOME UNCERTAINTY DEPENDING
ON DAYTIME MIXING...WHICH IS FORECAST TO BE UP TO AROUND 850 MB
AGAIN. HOWEVER...MOISTURE IS FORECAST TO INCREASE RELATIVE TO
TODAY AND THIS MAKES SENSE DUE TO A GREATER SOUTHERLY SYNOPTIC
FLOW AND LESS SYNOPTIC NORTHERLY FLOW.
FOR WEDNESDAY NIGHT...SIMILAR TEMPS TO PREVIOUS NIGHT WITH DRY
WEATHER IN PLACE.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
DEEP LAYERED RIDGING WILL REMAIN OVER THE EASTERN CONUS THROUGH
FRIDAY. BY FRIDAY NIGHT...THERE IS EXCELLENT AGREEMENT AMONG THE
OPERATIONAL AND ENSEMBLE GUIDANCE OF THE RIDGE BREAKING DOWN AND
SHIFTING OFFSHORE AS UPPER LEVEL HEIGHTS BEGIN TO FALL AHEAD OF A
TROUGHING BUILDING INTO THE NE US. THIS TROUGH SENDS A COLD FRONT
THROUGH THE AREA SATURDAY/SATURDAY NIGHT.
HOT AND HUMID CONDITIONS WILL CONTINUE INTO SATURDAY. H85 TEMPS ARE
FORECAST TO RANGE FROM 18C TO 20C ON THURSDAY AND FRIDAY HELPING TO
MAKE THESE DAYS THE HOTTEST OF THE EXTENDED PERIOD. HEAT ADVISORY
HAS BEEN EXTENDED UNTIL 8PM THURSDAY FOR NEW YORK CITY. FOR LOWER
HUDSON VALLEY...NE NJ...AND INTERIOR CT...IT IS POSSIBLE HEAT
ADVISORY CRITERIA WILL BE MET THURSDAY BUT CONFIDENCE IS LOW AT THIS
TIME. ONE POSSIBLE CAVEAT IS HOW MUCH DRIER AIR MIXES DOWN. SIMILAR
CONDITIONS/CONCERNS EXIST ON FRIDAY SO WILL NEED TO CONTINUE TO
MONITOR TRENDS. WITH A SURFACE TROUGH AND HIGH AMOUNTS OF
INSTABILITY THURS AND FRI...A SHOWER OR THUNDERSTORM CANNOT BE RULED
OUT. THESE WILL LIKELY BE PULSE IN NATURE AS SHEAR IS MINIMAL.
COLD FRONT THEN APPROACHES SATURDAY BRINGING MUCH BETTER CHANCES FOR
SHOWERS AND STORMS. WITH HEIGHT FALLS OCCURRING ALOFT AND BETTER
SYNOPTIC LIFT...THE CHANCES FOR SHOWERS AND STORMS INCREASE.
INGREDIENTS MAY BE PRESENT TO PROMOTE SEVERE WEATHER SAT WITH THE
FRONT. PRIMARY THREATS AT THIS TIME APPEAR TO BE DAMAGING WINDS. ANY
STORM MAY ALSO PRODUCE HEAVY RAINFALL AS PWATS APPROACH 2 INCHES
SATURDAY.
THE FRONT SHOULD MOVE SOUTH OF THE AREA SUNDAY. HOWEVER...12Z GFS
DOES SLOW ITS PROGRESSION WITH A WAVE DEVELOPING ALONG IT. THE
LATEST 12Z ECMWF AND 12Z CMC DO NOT DEPICT THIS SCENARIO...BUT DO
HINT AT A SLIGHTLY SLOWER PROGRESSION SOUTHWARD.
THEREFORE...LINGERED CHANCE POPS MAINLY ACROSS SOUTHERN ZONES
SUNDAY.
A RETURN TO MORE SEASONABLE CONDITIONS EXPECTED FOR EARLY NEXT WEEK
AS HIGH PRESSURE BUILDS INTO THE AREA.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
HIGH PRES REMAINS OVER THE AREA.
GENERALLY NNE TO NNW FLOW AT 8-12 KT WITH OCNL GUSTS OF 16-18 KT
OVER THE TERMINALS. SEA BREEZE NOTICEABLE ON TJKF ALONG THE
IMMEDIATE SOUTH SHORE AND BARRIER ISLANDS. THINK THIS SEA BREEZE
WILL MAKE IT TO KJFK EARLY THIS EVENING...AROUND 22Z...AND ANOTHER
SEA BREEZE COULD IMPACT KGON BY 20Z.
WINDS BECOME VRB AT 5 KT OR LESS AFT 02Z...AND THEN NE TO SE WINDS
INCREASE TO 5-7 KT AFT 14Z WEDNESDAY.
VFR THROUGH THE TAF PERIOD.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: LOW CONFIDENCE ON SEA BREEZE THIS AFTERNOON.
BEST TIMING WOULD BE AROUND 22Z...BUT TIMING COULD BE OFF BY AN
HOUR OR SO...IF THE SEA BREEZE DOES MOVE THROUGH THE TERMINAL.
HIGH CONFIDENCE WINDS TO THE RIGHT OF 310 TRUE OTHERWISE.
KLGA FCSTER COMMENTS: HIGH CONFIDENCE WINDS TO THE RIGHT OF 310
TRUE THROUGH THIS EVENING. VERY LOW CHANCE OF SEA BREEZE DURING
THE LATE AFTERNOON/EARLY EVENING HOURS.
KEWR FCSTER COMMENTS: HIGH CONFIDENCE WINDS TO THE RIGHT OF 310
TRUE THROUGH THIS EVENING. VERY LOW CHANCE OF SEA BREEZE DURING
THE LATE AFTERNOON/EARLY EVENING HOURS.
KTEB FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
KHPN FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
KISP FCSTER COMMENTS: HIGH CONFIDENCE WINDS TO THE RIGHT OF 310
TRUE THROUGH THIS AFTERNOON. LOW CHANCE SEA BREEZE IMPACTS
KISP...BUT IF IT DOES...IT WOULD OCCUR BETWEEN 20-22Z.
.OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY...
.WEDNESDAY-WEDNESDAY NIGHT...VFR.
.THURSDAY AND FRIDAY NIGHT...VFR. SLIGHT CHANCE SHRA/TSTM MAINLY
N AND W OF NYC DURING THE AFTERNOON/EVENING.
.SATURDAY...MAINLY VFR...BUT THE POTENTIAL LIES FOR WITH MVFR OR
LOWER CONDS IN STRONG TO SEVERE CONVECTION.
.SUNDAY...IMPROVING CONDS.
&&
.MARINE...
SUB SCA CONDITIONS ARE EXPECTED TO PREVAIL THROUGH WEDNESDAY NIGHT WITH
A WEAK PRESSURE GRADIENT IN PLACE.
A 15-20KT SW FLOW DEVELOPS OVER THE WATERS WITH GUSTS LIKELY
APPROACHING SCA LEVELS FRIDAY INTO SATURDAY. SEAS WILL ALSO BUILD TO
SCA LEVELS DURING THIS TIME. SUNDAY INTO MONDAY...WINDS SHOULD
REMAIN BELOW SCA LEVELS WITH MARGINAL SCA SEAS.
&&
.HYDROLOGY...
DRY CONDITIONS ARE EXPECTED THROUGH WEDNESDAY NIGHT.
A MOIST AIRMASS OVER THE AREA THURSDAY INTO FRIDAY BRINGS THE
POTENTIAL FOR HEAVY DOWNPOURS. HOWEVER...THUNDERSTORMS SHOULD REMAIN
ISOLATED LIMITING ANY FLASH FLOODING POTENTIAL. THE CHANCE FOR FLASH
FLOODING INCREASES ON SATURDAY WITH BETTER THUNDERSTORM COVERAGE AND
PRECIPITABLE WATERS INCREASING TO AROUND 2 INCHES.
&&
.CLIMATE...
TUESDAY JULY 16 2013 RECORD MAXIMUM TEMPERATURES
SITE RECORD FORECAST HIGH
BRIDGEPORT 94 (1983, 1952) 95
ISLIP 93 (1999) 95
LAGUARDIA 97 (1980) 97
KENNEDY 100 (1983) 95
CENTRAL PARK 99 (1980) 96
NEWARK 101 (1988) 97
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR CTZ005>012.
NY...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NYZ067>071-078-
080-177-179.
HEAT ADVISORY UNTIL 8 PM EDT WEDNESDAY FOR NYZ072>075-176-178.
NJ...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NJZ004-006-
103>108.
MARINE...NONE.
&&
$$
SYNOPSIS...JM/DS
NEAR TERM...JM
SHORT TERM...JM
LONG TERM...DS
AVIATION...MPS
MARINE...JM/DS
HYDROLOGY...JM/DS
CLIMATE...DH/JM
AREA FORECAST DISCUSSION
NWS TAUNTON MA
357 PM EDT TUE JUL 16 2013
.SYNOPSIS...
HOT AND HUMID WEATHER WILL CONTINUE THIS WEEK WITH ONLY AN
ISOLATED SHOWER OR THUNDERSTORM THROUGH WEDNESDAY. CHANCES FOR
SHOWERS AND THUNDERSTORMS WILL INCREASE THURSDAY...FRIDAY AND
ESPECIALLY SATURDAY AS A COLD FRONT APPROACHES FROM THE GREAT
LAKES. RELIEF FROM THE HEAT AND HUMIDITY WILL ARRIVE ON SUNDAY
BEHIND A STRONG COLD FRONT AND LAST THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
235 PM UPDATE...
UPDATE...HAVE UPPED TEMPERATURES FOR THE ISLANDS FOR THE
REMAINDER OF THE LATE AFTERNOON/EVENING. HAVE NOW REACHED 86 AT
ACK, 89 AT MVY, AND 90 AT BID.
PREVIOUS DISCUSSION...
THE HOT WEATHER IS OCCURRING AGAIN...WITH 1 PM TEMPS ALREADY IN
THE LOW TO MID 90S ACROSS MUCH OF THE REGION. HEAT INDICES HAVE
TOPPED OUT AT 96 SO FAR AT BOSTON AND NEW BEDFORD. SO...NO CHANGE
TO THE HEAT ADVISORIES...ALTHOUGH MARGINAL. A FEW PLACES MAY HIT
100 LOCALLY FOR A COUPLE OF HOURS IN THE ADVISORY AREA.
A FEW SHOWERS HAVE POPPED IN SOUTHEASTERN MAINE...DRIFTING
SOUTHWARD TOWARD THE NEW HAMPSHIRE SEACOAST. THE 12Z NAM MODEL
SHOWS SHOWERS OR TSTM CHANCES BLOSSOMING ACROSS EASTERN MA TOWARD
EVENING. THINK THAT THIS IS OVERDONE. GFS HAS BACKED OFF OF ITS
PREVIOUS K INDEX FORECAST OF 32-34...MORE LIKE 28-30 NOW THIS
EVENING ALONG THE ROUTE 2 CORRIDOR. THUS CANNOT RULE OUT ISOLATED
TO WIDELY SCATTERED SHOWERS/TSTMS ANYWHERE ACROSS NORTHERN MA OR
ALONG THE SEA BREEZE IN EASTERN MA LATE THIS AFTERNOON...BUT ANY
CONVECTION SHOULD DISSIPATE AFTER SUNDOWN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
TONIGHT...
DIURNAL DWPT RISE AND WARM TEMPERATURES WILL LEAD TO ANOTHER WARM
HUMID NIGHT TONIGHT WITH MANY LOCATIONS REMAINING IN THE 70S AND
UPPER 60S. ANY SHOWER/T-STORMS WILL DIMINISH RAPIDLY WITH THE LOSS
OF DIURNAL HEAT SUPPORT IN THE EVENING...AND ANY DIURNAL CU WILL
DIMINISH THANKS TO THE DRY SUBSIDENCE INVERSION GIVING WAY TO
PARTLY CLOUDY TO MOSTLY SKC BY THE EARLY MORNING HOURS.
WEDNESDAY...
SIMILAR TO TUESDAY IN THAT A WARM START AND PARTLY CLOUDY-MOSTLY
CLEAR CONDITIONS WILL GIVE WAY TO ANOTHER HOT DAY WITH HIGH TEMPS
APPROACHING THE MID 90S ONCE AGAIN THANKS TO A MODIFIED AIRMASS.
DWPTS MAY ONCE AGAIN BE CLOSE ENOUGH TO SUPPORT HEAT INDEX VALUES
NEAR 100F ACROSS THE REGION AS SOUNDINGS SUGGEST A SLIGHT
MOISTENING OF THE AIRMASS. WILL NEED TO MONITOR FOR ANOTHER HEAT
ADVISORY.
SLIGHTLY HIGHER CHANCE FOR AFTERNOON/EVENING SHOWERS AND
THUNDERSTORMS ON WED AS A WAVE OF LOW PRES PASSES THROUGH NRN NEW
ENGLAND PUSHING A RAPIDLY WEAKENING COLD FRONT INTO SRN NEW
ENGLAND BY THE AFTERNOON HOURS. HIGH PRES RIDGE STILL IN CONTROL
THOUGH WITH CAP AROUND H7 AND LOW /ALTHOUGH SLIGHTLY HIGHER THAN
TUE/ MID LVL LAPSE RATES. SB CAPE VALUES LOOK TO BE A BIT HIGHER
THANKS TO THE INCREASING MOISTURE WITHIN THE COLUMN...AVERAGING
ABOUT 1000-1500 J/KG. THEREFORE...WENT WITH MORE WIDESPREAD SLIGHT
CHANCE TO NEAR CHANCE POPS ACROSS THE REGIONS GIVEN THE POTENTIAL
FOR WEAK FORCING. WITH LITTLE TO NO SHEAR THOUGH...ANY STORMS THAT
DO DEVELOP WOULD BE UP AND DOWN RATHER RAPIDLY SINCE THEY WOULD
LIKELY BE UNABLE TO ORGANIZE.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
HEADLINES...
* HOT/HUMID THU INTO SAT WITH SCATTERED T-STORMS
* SEVERE STORMS POSSIBLE AHEAD OF A COLD FRONT SAT
* SEASONABLE AND DRY SUNDAY INTO THE BEGINNING OF NEXT WEEK
DETAILS...
NOT MUCH CHANGE IN OUR FORECAST THINKING FROM PREVIOUS SHIFTS.
MODELS REMAIN IN GOOD OVERALL AGREEMENT SHIFTING H5 HIGH SOUTH
AND WEST TOWARDS THE FOUR-CORNERS REGION ALLOWING FOR FALLING
HEIGHTS ACROSS NEW ENGLAND. THIS RESULTS IN THE RETURN OF THE
NORTHERN STREAM AS DOMINANT INFLUENCE AND SUBSEQUENTLY A MORE
ACTIVE PATTERN.
THURSDAY...
MODELS KEY ON LEE TROUGH BECOMING FOCUS FOR SCATTERED AFTERNOON
CONVECTION. SURFACE-BASED CAPES REACH 1500 J/KG WITH DECENT MID
LEVEL LAPSE RATES AROUND 6C/KM...BUT 0-6KM SHEAR IS MARGINAL AT
BEST. STILL NEED TO OVERCOME RATHER WARM MID LEVEL TEMPERATURES...
SO NOT CONFIDENT THAT STORM COVERAGE WILL BE ALL THAT GREAT. KEPT
CHANCE POPS FOR SCATTERED AFTERNOON THUNDERSTORMS WITH CONTINUED
MENTION OF HEAVY RAIN.
HIGH CAPE ENVIRONMENT FAVORS STRONG TO ISOLATED SEVERE STORMS...
BUT OVERALL SEVERE THREAT APPEARS TO BE LIMITED. PRECIPITABLE
WATER VALUES APPROACHING 2 INCHES...WHICH IS AROUND +2 STANDARD
DEVIATIONS...MEANS POTENTIAL FOR HEAVY RAINFALL AND ISOLATED
FLOODING IN STORMS.
HIGHS IN 90S AWAY FROM S COAST COMBINED WITH DEW POINTS IN LOWER
70S WILL ONCE AGAIN YIELD HEAT INDICES AROUND 100.
FRIDAY...
FLOW ALOFT BECOMES FLATTER WHICH SHOULD ALLOW ANY UPSTREAM
ACTIVITY TO PASS TO OUR N. HOWEVER WE REMAIN IN UNSTABLE AIRMASS
WITH BETTER CONVECTIVE POTENTIAL THAN THU. MODELS SHOW SURFACE
BASED CAPES 2000-3000 J/KG AND MID LEVEL LAPSE RATES OVER 6C/KM.
AXIS OF GREATEST 0-6KM SHEAR REMAINS ACROSS NORTHERN NEW ENGLAND
BUT SW NH AND NORTHERN MA ARE ON PERHIPHERY OF THIS AXIS WITH
VALUES OF 30-35KT. IN ADDITION WE ARE IN FAVORABLE RR QUAD OF
UPPER JET. ONLY LIMITING FACTOR APPEARS TO BE WARM MID LEVEL TEMPS
/+11C AT 700 MB/ BUT COLDER AIR ALOFT SHOULD BE ABLE TO
COMPENSATE.
EXPECT SCATTERED STORMS TO DEVELOP FRI AFTERNOON ACROSS MUCH OF
SOUTHERN NEW ENGLAND...ASIDE FROM IMMEDIATE S COAST WHICH WILL BE
MORE STABLE DUE TO SW FLOW. SEVERE POTENTIAL IS SOMEWHAT BETTER
THAN THU WITH BETTER POSSIBILITY OF DAMAGING WINDS DUE TO BOWING
SEGMENTS OR LINES. ALSO HAVE CONTINUED POTENTIAL FOR HEAVY
RAINFALL AND ISOLATED FLOODING.
INCREASING SW FLOW WILL RESULT IN WARMER DAY THAN THU. HIGHS
SHOULD TOP OUT IN LOW-MID 90S /GIVEN MODEL 2M TEMPERATURES/
COMBINED WITH DEW POINTS IN LOW-MID 70S SHOULD YIELD HEAT INDICES
OF 100-105. NOT CONFIDENT ENOUGH TO ISSUE EXCESSIVE HEAT WATCH BUT
WE MAY NEED TO DO SO IF THIS BECOMES MORE CERTAIN.
SATURDAY...
BEST POTENTIAL FOR ORGANIZED CONVECTION AS STRONG COLD FRONT
APPROACHES FROM GREAT LAKES. SOME QUESTION AS TO WHETHER OR NOT
ANY EARLY MORNING CONVECTION WILL INHIBIT SIGNIFICANT
DESTABILIZATION DURING AFTERNOON. PATTERN SEEMS TO FAVOR AT LEAST
MORNING SHOWERS/STORMS NEAR S COAST...THEN WE SEE A BREAK BEFORE
ADDITIONAL STORMS FIRE DURING AFTERNOON AND EVENING.
NO REAL CHANGE IN THINKING FROM SPC DAY 4 OUTLOOK AND PREVIOUS
DISCUSSION. EXPECTED INSTABILITY COUPLED WITH BULK SOUTHWESTERLY
UNI-DIRECTIONAL SHEAR AROUND 35 KTS FAVORS MULTICELLS AND LINE
ECHO WAVE PATTERNS WITH DAMAGING WINDS MAIN THREAT. ALSO NEED TO
BE AWARE OF CONTINUED FLASH FLOOD POTENTIAL WITH PRECIPITABLE
WATER VALUES NEAR 2 INCHES.
SUNDAY INTO THE EARLY WEEK...
COLD FRONT WILL HEAD OFFSHORE SUN MORNING...PERHAPS NOT UNTIL SUN
AFTERNOON ON CAPE COD. COOLER AND DRIER AIR WILL FOLLOW ON NW
WINDS LATER SUN. FRONT MAY BECOME STATIONARY AS IT RUNS UP INTO
RIDGING OVER WESTERN ATLANTIC. THIS WOULD KEEP US IN NE FLOW
MON/TUE WITH DRY WEATHER ANTICIPATED...ALTHOUGH IT IS POSSIBLE ONE
OR TWO WEAK AREAS OF LOW PRESSURE COULD COME CLOSE ENOUGH TO BRING
AT LEAST SOME CLOUDINESS TO SE NEW ENGLAND.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT-TERM /THROUGH WEDNESDAY/...HIGH CONFIDENCE.
VFR THROUGHOUT. SEA-BREEZES ALONG THE SHORES. ISOLATED
SHOWER/T-STORM POSSIBLE PARTICULARLY SRN NH AND NORTHEAST MA...
AND PERHAPS ALONG THE SEA BREEZE FRONT IN EASTERN MA. VERY LOW
CONFIDENCE IN MORE FOG WITH MVFR VSBYS TONIGHT. OTHERWISE VFR
CONTINUES.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...THURSDAY THROUGH SUNDAY...
THURSDAY AND FRIDAY...MODERATE CONFIDENCE. IFR IN S COASTAL FOG
EARLY. ISOLATED SHOWERS/TSTMS WITH LOCAL IFR IN AFTERNOON.
SATURDAY...MODERATE CONFIDENCE. IFR IN S COASTAL FOG EARLY.
SCATTERED SHOWERS/TSTMS WITH LOCAL IFR IN AFTERNOON/EVENING.
SUNDAY...MODERATE CONFIDENCE. BECOMING VFR BY AFTERNOON.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
HIGH CONFIDENCE...
WINDS AND SEAS REMAIN BELOW SMALL CRAFT ADVISORY LEVELS THROUGH
THE PERIOD AS HIGH PRES REMAINS IN CONTROL. THERE IS THE CHANCE
FOR SOME REDUCED VSBYS IN FOG IN SOME SPOTS.
OUTLOOK...THURSDAY THROUGH SUNDAY...
THURSDAY AND FRIDAY...HIGH CONFIDENCE.
WEAK GRADIENT WILL RESULT IN SEA BREEZES ALONG E COAST WITH MORE
OF A SW FLOW ALONG S COAST WHERE 20KT GUSTS POSSIBLE. ISOLATED
THUNDERSTORMS POSSIBLE BOTH DAYS NEAR SHORE. EXPECT AREAS OF
NIGHTTIME AND EARLY MORNING FOG AROUND CAPE COD.
SATURDAY...MODERATE CONFIDENCE.
APPROACHING COLD FRONT WILL BRING INCREASING SW FLOW ON ALL WATERS
AS SEAS SLOWLY BUILD ON S COASTAL WATERS. STAYED BELOW WAVE WATCH
MODEL FORECAST OF 6-8 FT AS THIS MODEL IS TYPICALLY OVERDONE IN SW
FLOW DURING SUMMER...SHOULD BE MORE LIKE 4-5 FT AT MOST AND SCA
WILL PROBABLY BE NEEDED OFFSHORE.
AREAS OF NIGHTTIME AND EARLY MORNING FOG SHOULD PERSIST AROUND
CAPE COD.
SCATTERED THUNDERSTORMS POSSIBLE IN TWO ROUNDS...FIRST EARLY SAT
MORNING /PERHAPS NEAR S COAST?/ AND AGAIN TOWARD EVENING INTO SAT
NIGHT AS COLD FRONT PUSHES THROUGH NEW ENGLAND.
SUNDAY...MODERATE CONFIDENCE.
WINDS SHIFT TO NW AND DIMINISH AS COLD FRONT HEADS OFFSHORE BY
AFTERNOON. SEAS SLOWLY DIMINISH AS WELL BUT SHOULD REMAIN AT 5 OR
6 FT SE OF CAPE COD. SHOWERS/THUNDERSTORMS SHOULD LINGER
INITIALLY ON WATERS SE OF NANTUCKET BUT SHOULD BE WELL OFFSHORE BY
EARLY AFTERNOON.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR CTZ002>004.
MA...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR MAZ010-011-013-
017-018.
NH...NONE.
RI...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR RIZ001>004-006.
MARINE...NONE.
&&
$$
SYNOPSIS...DOODY/SIPPRELL
NEAR TERM...GAF
SHORT TERM...DOODY
LONG TERM...JWD
AVIATION...JWD/GAF
MARINE...JWD/GAF
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
610 PM EDT TUE JUL 16 2013
.UPDATE (REST OF TONIGHT AND WEDNESDAY)...
22Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS AN UPPER LEVEL PATTERN
DOMINATED BY AN IMMENSE UPPER RIDGE CENTERED OVER THE MIDWEST
STATES. VERY IMPRESSIVE H5 HEIGHTS OF UP TO 600DM CONTINUE TO BE
SEEN UNDER THE CENTER OF THIS RIDGE. UNUSUALLY BEHAVED UPPER LOW FOR
JULY NOW OVER NEW MEXICO HAS BEEN RETROGRADING WESTWARD THE PAST FEW
DAYS AROUND THE SOUTHERN PERIPHERY OF THE RIDGE. OTHER FEATURE OF
NOTE FOR OUR FORECAST IS A WEAK UPPER LOW/DISTURBANCE SPINNING OVER
THE SOUTHERN HALF OF THE FL PENINSULA/FL STRAITS. THIS CYCLONIC EDDY
IS FORECAST TO VERY SLOWLY MOVE WESTWARD INTO THE SOUTHEAST GULF OF
MEXICO ON WEDNESDAY.
AT THE SURFACE...EASTERLY FLOW DOMINATES THE REGION ON THE FAR
SOUTHERN PERIPHERY OF 1025MB HIGH PRESSURE CENTERED NEAR
INDIANAPOLIS THIS EVENING. THIS EASTERLY FLOW WILL LINGER THROUGH AT
LEAST WEDNESDAY BEFORE THE SUBTROPICAL RIDGE AXIS REBUILDS OVER THE
PENINSULA AND WEAKENS THE GRADIENT.
LOCAL WEATHER THE PAST SEVERAL HOURS HAS BEEN INFLUENCED HIGHLY BY
AN IMPULSE...LIKELY GRAVITY WAVE THAT INITIATED FROM CONVECTION DOWN
OVER SE FLORIDA EARLIER TODAY. THIS GRAVITY WAVE HAS BEEN
PROPAGATING NORTHWARD THROUGH THE MID AFTERNOON AND EARLY EVENING
HOURS ENHANCING THE CONVECTION AS IT WENT. THIS FEATURE IS VERY
EVIDENT IF LOOKING AT A FAST PACED AND LONG DURATION RADAR LOOP OVER
THE PAST 6 OR SO HOURS. WHAT IS LEFT OF THIS IMPULSE IS NOW UP OVER
THE NORTHERN NATURE COAST AND SHOULD EXIT NORTH OF LEVY COUNTY SOON.
IN ITS WAKE...CONDITIONS QUIET DOWN QUICKLY AND HAVE SIGNIFICANTLY
DECREASED POPS GOING INTO THE MIDDLE/LATER EVENING HOURS FOR ALL
ZONES SOUTH OF LEVY COUNTY. LEFT A 20% RAIN CHANCE IN FOR MOST AREAS
THROUGH 03Z TO ACCOUNT FOR ANY STRAY SHOWERS THAT CAN DEVELOP AT
JUST ABOUT ANY TIME UNDERNEATH THE CYCLONIC FLOW OF THE MORE BROAD
UPPER LOW. HOWEVER...LOOKS LIKE MUCH OF THE RAINFALL FOR THE DAY HAS
ENDED FOR AREAS SOUTH OF CRYSTAL RIVER...AND WILL BE ENDING FOR
SUMTER/CITRUS/LEVY COUNTY IN THE NEXT COUPLE OF HOURS AS WELL.
THE REMAINDER OF THE OVERNIGHT LOOKS RATHER QUIET...WITH THE BEST
CHANCE OF LAND BASED SHOWERS AFTER 03Z BEING DOWN TOWARD THE
CHARLOTTE/LEE COUNTIES (BUT ONLY 20-30%).
FOR WEDNESDAY...
A GENERAL CYCLONIC FLOW ALOFT WILL STILL BE PRESENT ASSOCIATED WITH
THE WEAK UPPER LOW ALONG/JUST OFF THE SW FL COAST. BEST CHANCES FOR
DEVELOPING DIURNAL SHOWERS/STORMS (50-60%) SHOULD EXIST SOUTH OF
I-4...COINCIDENT WITH THE DEEPER MOISTURE FIELDS ADVERTISED BY THE
GFS/ECMWF. AREAS FURTHER NORTH SHOULD STILL SEE SOME FAST MOVING
SHOWERS PROGRESSING FROM EAST TO WEST...HOWEVER COVERAGE COULD BE
DESCRIBED AS MORE SCT (30-40%) IN NATURE.
&&
.AVIATION...
AFTERNOON SHRA AND TSRA HAVE PUSHED OFFSHORE AND WEAKENED. VFR
CONDITIONS OVERNIGHT THROUGH WED MORNING. SCT-NMRS TSRA IN THE
AFTERNOON WITH MVFR/LCL IFR POSSIBLE. LIGHT NE WINDS
OVERNIGHT...EASTERLY AND SLIGHT STRONGER WED.
&&
.MARINE...
EXPECT EXERCISE CAUTION CRITERIA FOR THE OFFSHORE WATERS
TONIGHT...WITH WINDS OF 15 TO 20 KNOTS EXPECTED. SEAS WILL BE UP
TO 4 FEET. OTHERWISE BOTH WINDS AND SEAS ARE FORECAST TO REMAIN
BELOW ADVISORY AND CAUTIONARY LEVELS.
&&
.FIRE WEATHER...
NO CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 75 90 74 88 / 20 50 30 60
FMY 73 88 72 88 / 20 60 30 60
GIF 72 90 73 91 / 20 50 20 50
SRQ 74 91 73 87 / 20 50 30 60
BKV 71 91 70 89 / 20 40 20 50
SPG 78 90 77 87 / 20 40 30 60
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE...MROCZKA
AVIATION...RUDE
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
130 PM EDT TUE JUL 16 2013
.PREV DISCUSSION...
UPDATE...
/ISSUED 1137 AM EDT TUE JUL 16 2013/
MAIN CHANGE FOR THE UPDATE WAS TO REDUCE POPS INITIALLY. HRRR IS
SUGGESTING EXTENSIVE DEVELOPMENT ACROSS THE MOUNTAINS THIS
AFTERNOON. NAM/SREF/GFS ARE PICKING UP ON SOME ACTIVITY UP THERE
AFTER 18Z. WILL BE WATCHING THIS AREA FOR THE POTENTIAL NEED TO
INCREASE POPS ACROSS THE MOUNTAINS INTO THE AFTERNOON. HAVE CHANCE
POPS ACROSS THE SOUTHERN THIRD OF THE CWA...BUT SHOULD SEE BETTER
COVERAGE REMAIN SOUTH AND EAST OF THE AREA.
11
SHORT TERM /TODAY THROUGH WEDNESDAY/...
UPPER RIDGE REMAINS ANCHORED OVER THE OHIO VALLEY/GREAT LAKES AREA
TODAY INTO WEDNESDAY. EASTERLY FLOW WILL DOMINATE THROUGH MOST
LEVELS OF THE ATMOSPHERE THROUGH THE SHORT TERM. FORECAST SOUNDINGS
SHOWING PRECIPITABLE WATER DECREASING SOME TODAY. POPS IN THE 20 TO
30 PERCENT RANGE LOOK REASONABLE ACROSS THE CWA...FAVORING THE
AFTERNOON AND DIMINISHING AROUND 04Z. FOR WEDNESDAY...BOTH GFS AND
NAM INDICATE A WEAK SHORT WAVE MOVING WESTERLY AROUND THE EDGE OF
THE RIDGE FROM THE CAROLINAS INTO GA. ALSO...PW VALUES ARE ON THE
INCREASE BY THEN. BASED ON THIS HAVE PUSHED POPS UP A BIT ON
WEDNESDAY...STILL MOSTLY DIURNAL. MAX TEMPERATURES SHOULD RANGE IN
THE MID 80S TO LOW 90S NEXT COUPLE OF DAYS.
41
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
HIGH PRESSURE ALOFT WILL BE OVER THE OH-MID MS VALLEYS TO START THE
LONG TERM AND IS FORECAST TO WEAKEN THURSDAY. A MOIST AIRMASS WILL
STILL BE IN PLACE AND WITH ANY INSTABILITY WILL LEAD TO ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS. MODELS HINTING THAT AN UPPER
LEVEL DISTURBANCE COULD AFFECT THE AREA THURSDAY AND THIS IS MAKING
TIMING OF ANY CONVECTION DIFFICULT AS CONVECTION COULD OCCUR EARLIER
ON THURSDAY THAN THE MORE NORMAL DIURNAL TENDENCY.
UPPER HIGH CONTINUES TO WEAKEN ON FRIDAY WITH PLENTY OF MOISTURE AND
AFTERNOON/EVENING INSTABILITY IN PLACE. A TRANSITION TO WESTERLY FLOW
OCCURS STARTING SATURDAY AND THIS EVENTUALLY DEVELOPS INTO A TROUGH
ALOFT INTO TUESDAY WITH POTENTIAL FOR SHORT WAVE ENHANCEMENT OF ANY
CONVECTION. PLENTY OF MOISTURE WILL CONTINUE TO BE AVAILABLE ALONG
WITH MAINLY DIURNAL INSTABILITY. THIS WILL LEAD TO AT LEAST
SCATTERED SHOWERS AND THUNDERSTORMS THROUGH THE PERIOD INTO TUESDAY.
TEMPERATURES SHOULD GENERALLY BE CLOSE TO NORMAL WITH THE HIGHS
SLIGHTLY BELOW NORMAL FROM ABOUT SATURDAY ON.
BDL
&&
.AVIATION...
18Z UPDATE...
BEST CHANCES FOR CONVECTION THIS AFTERNOON SHOULD BE ACROSS THE
NORTH GEORGIA MOUNTAINS AND ACROSS THE SOUTHERN PORTIONS OF
CENTRAL GEORGIA...THUS NORTH AND SOUTH OF THE TAF SITES. MCN HAS
THE BEST CHANCE OF SEEING A TSRA...BUT CHANCE IS SO LOW AT ALL THE
SITES THAT IT ISNT MENTIONED IN THE TAFS FOR THIS AFTERNOON.
SHOULD SEE SCT-BKN CLOUDS CONTINUE THROUGH THE AFTERNOON...BUT
CLOUD HEIGHTS SHOULD CONTINUE TO INCREASE.
//ATL CONFIDENCE...18Z UPDATE...
HIGH CONFIDENCE ON WIND..EXCEPT LOW CONFIDENCE ON TIMING OF WIND
SHIFT TOMORROW. HIGH CONFIDENCE ON CIGS AND VSBYS.
11
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 91 71 91 71 / 20 20 40 40
ATLANTA 87 73 91 72 / 20 20 40 40
BLAIRSVILLE 89 67 87 67 / 20 20 40 40
CARTERSVILLE 90 70 91 68 / 20 20 40 40
COLUMBUS 91 73 92 73 / 20 20 20 20
GAINESVILLE 89 72 91 72 / 20 20 40 40
MACON 91 70 92 70 / 20 20 30 30
ROME 91 70 92 69 / 20 20 40 40
PEACHTREE CITY 89 70 91 69 / 20 20 40 40
VIDALIA 91 73 91 72 / 30 30 20 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...11
LONG TERM....01
AVIATION...11
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
509 PM CDT TUE JUL 16 2013
.DISCUSSION...
248 PM CDT
PRIMARY FORECAST CHALLENGE REMAINS THE HEAT AND HUMIDITY AND THE
POTENTIAL FOR HEAT HEADLINES LATER THIS WEEK.
STRONG UPPER RIDGE REMAINS SITUATED OVER THE REGION AND DESPITE
CONCERNS EARLIER THIS MORNING TO THE CONTRARY...HAS GENERALLY KEPT A
CHECK ON ISOLATED AFTERNOON THUNDERSTORM DEVELOPMENT. IT REMAINS
UNSTABLE AND LARGELY UNCAPPED...SO CAN`T RULE OUT SOME RENEGADE
STORMS POPPING BUT THINKING COVERAGE WILL BE LESS THAN EARLIER
FEARED THIS AFTERNOON. REALLY LOOKS LIKE THE SAME STORY WEDNESDAY
AND THURSDAY AS WELL WITH STRONG UPPER RIDGE OVERHEAD AND NO SUPPORT
ALOFT DESPITE STRONG INSTABILITY AND MINIMAL CAPPING...SO PLAN TO
KEEP POPS IN THE 10-15% RANGE IN THE GRIDS AND THE MENTION OF
THUNDERSTORMS OUT OF THE TEXT PRODUCTS FOR NOW WITH THE EXPECTATION
OF ANYTHING THAT DOES MANAGE TO DEVELOP REMAINING HIGHLY ISOLATED.
REGARDING TEMPS AND HEAT INDICES...EXPECT TOMORROW TO BE LARGELY A
REPEAT OF TODAY OR MAYBE A SMIDGE HOTTER WITH THURSDAY THE SAME
STORY. HEAT INDICES THIS AFTERNOON HAVE GENERALLY CLIMBED INTO THE
95-100 RANGE EXCEPT AT A COUPLE OF AWOS SITES THAT HAVE THE MOST
PROFUSELY SWEATING CORN AROUND IT (IE. DKB/SQI). ASSUMING DEWPOINTS
HOLD IN THE LOW 70S THE NEXT COUPLE DAYS (WHICH SEEMS
REASONABLE)...THEN HEAT INDICES WOULD LIKELY TOP OUT AROUND 100
WEDNESDAY AND A BIT ABOVE 100 THURSDAY AND FRIDAY. LOW TEMPS IN THE
OUTLYING AREAS LAST NIGHT WERE MOSTLY IN THE LOW 70S...SO UNLESS LOW
TEMPS START HOLDING IN THE MID TO UPPER 70S IN OUTLYING AREAS THE
NEXT COUPLE NIGHTS WE WILL PROBABLY BE ABLE TO HOLD OFF ON THE 4
DAY OF 100F+ HEAT INDEX CRITERIA FOR AN ADVISORY. COOK COUNTY AND
THE CITY OF CHICAGO IS A DIFFERENT STORY ONLY REQUIRING 3 DAYS OF
100-105 HEAT INDICES WITH EITHER 85% SUNSHINE 2 OF THE DAYS OR
NIGHT TIME HEAT INDICES ABOVE 80 FOR AN EXCESSIVE HEAT WARNING AND
WE WILL BE VERY CLOSE TO THIS CRITERIA WED-FRI. WE ARE FLIRTING
WITH 100F HEAT INDICES THIS AFTERNOON...THOUGH LAKE BREEZE HAS
RESULTING IN COOLING CLOSE TO THE LAKE. WEDNESDAY COULD SEE SOME
LAKE COOLING AGAIN BUT THURSDAY AND ESPECIALLY FRIDAY SHOULD BE
VOID OF ANY LAKE BREEZES. PONDERED AN EXCESSIVE HEAT WATCH FOR
COOK COUNTY BUT STILL NOT TERRIBLY CONFIDENT IN SOLIDLY REACHING
100F H.I. CRITERIA TOMORROW WITH LAKE BREEZE POTENTIAL...SO HAVE
OPTED TO HOLD OFF ON ANY HEADLINES FOR NOW.
FAIRLY HEALTHY COLD FRONT STILL SLATED TO MOVE THROUGH FRIDAY NIGHT
POTENTIALLY BRINGING A ROUND OF SHOWERS AND THUNDERSTORMS TO THE
AREA LATE FRIDAY AND ESPECIALLY FRIDAY NIGHT. COOLER AND MUCH LESS
HUMID AIR MASS WILL FILTER INTO THE REGION THIS WEEKEND LIKELY
LEADING TO A PRECIPITATION FREE WEEKEND.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* LAKE BREEZE TO STAY EAST OF AIRPORTS
* VERY SMALL CHANCE OF A THUNDERSTORM NEXT 2-3 HOURS
* SOME HAZE/LIGHT FOG AROUND SUNRISE
ALLSOPP
//DISCUSSION...UPDATED 22Z...
LAKE BREEZE NOT MAKING ANY PROGRESS INLAND. HIGH RES HRRR MODEL
STILL SUGGESTING LAKE BREEZE WILL MAKE IT OUT TO ORD AND MDW BUT
NOT TIL AFTER 00Z...BUT OTHER SHORT RANGE HIGH RES GUIDANCE KEEPS
IT ALONG THE SHORE. BASED ON CURRENT TRENDS HAVE DECIDED TO BACK
OFF AND LEAVE WINDS SOUTHWEST THROUGH EARLY EVENING. ALSO THERE
HAS BEEN NO CONVECTION ALONG THE LAKE BREEZE THIS FAR AND VISIBLE
SATELLITE ACTUALLY SHOWING DECREASING TREND IN CUMULUS FIELD LAST
COUPLE HOURS. STILL CANT COMPLETELY RULE OUT AN ISOLATED SHOWER OR
THUNDERSTORMS POPPING ALONG THE LAKE BREEZE BUT FEEL THE CHANCE
OF IT OCCURRING WITHIN 5 MILES OF EITHER AIRPORT IS 10 PERCENT OR
LESS. THEREFORE HAVE DROPPED THE VCTS FROM TAFS.
ALLSOPP
PREVIOUS DISCUSSION 18Z...
CONCERNS FOR A LAKE BREEZE THIS AFTERNOON AND A WIND SHIFT DUE TO A
LAKE BREEZE CONTINUE THIS AFTERNOON. THE AREA REMAINS UNDER A VERY
UNSTABLE AND WEAKLY CAPPED AIRMASS. WEAK MID LEVEL LAPSE RATES AND
LACK OF ANY UPPER LEVEL SUPPORT HAVE INHIBITED DEEP CONVECTION THUS
FAR...BUT MODIFIED NAM/AMDAR SHOW THAT WITH ONLY A LITTLE MORE
SURFACE HEATING...DEEP CONVECTION/THUNDERSTORM DEVELOPMENT REMAINS A
DISTINCT POSSIBILITY. LACK OF ANY SYNOPTIC FORCING MAY KEEP COVERAGE
ON THE LOW END...BUT THE LAKE BREEZE STILL APPEARS TO BE THE BEST
FOCUS...AND ANY THUNDERSTORMS THAT DO DEVELOP WILL LIKELY BE SLOW
MOVING AND PULSY.
THE LAKE BREEZE HAS BEEN SLOW TO DEVELOP WITH MODEST SOUTHWEST FLOW
IN PLACE...BUT SENSORS IN DOWNTOWN CHICAGO AND AT THE CHICAGO CRIB A
FEW MILES OFF SHORE HAVE SHOWN HINTS OF IT TRYING TO BECOME BETTER
ORGANIZED...INCLUDING THE NORTHERLY ISLAND SENSOR RECENTLY TURNING
E. PUSHED BACK THE TIMING WHICH IS IN LINE WITH LATEST RAP/HRRR RUNS
THOUGH CONFIDENCE ON REACHING THE TERMINALS IS LESS THAN BEFORE.
OVERNIGHT...LIGHT SOUTHWESTERLY WINDS WILL TAKE OVER AGAIN. MUGGY
AIRMASS REMAINS IN PLACE AND COOLING WILL LEAD TO MODEST REDUCTIONS
IN VSBY DUE TO MIST/HAZE.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* LOW CONFIDENCE IN LAKE BREEZE MAKING TO ORD OR MDW.
* LOW CONFIDENCE IN THUNDERSTORM OCCURRING WITHIN 5 MILES OF ORD/MDW.
* MEDIUM CONFIDENCE IN HAZE OR LIGHT FOG AROUND SUNRISE.
ALLSOPP
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...MVFR VISIBILITY OVERNIGHT DUE TO BR HZ.
OTHERWISE...VFR...NO SIG WX.
THURSDAY...POSSIBLE MVFR VISIBILITY EARLY MORNING AND LATE
OVERNIGHT DUE TO BR HZ. OTHERWISE...VFR...NO SIG WX.
FRIDAY...INCREASING CHANCES OF TS AS DAY PROGRESSES...FROM SLIGHT
CHANCE IN THE MORNING TO CHANCE IN AFTERNOON AND LIKELY FRIDAY
NIGHT. ANY TSRA WOULD PRODUCE OF MVFR AND POSSIBLY BRIEF IFR
CONDITIONS.
SATURDAY...SLIGHT CHANCE OF TS. OTHERWISE VFR.
SUNDAY...VFR...NO SIG WX.
MONDAY...CHANCE OF TSRA...OTHERWISE VFR.
&&
.MARINE...
303 PM CDT
LIGHT SOUTH/SOUTHWEST FLOW WILL CONTINUE OVER THE OPEN WATERS
THROUGH THURSDAY. A COLD FRONT WILL LIKELY STALL JUST NORTH OF THE
NORTH TIP OF THE LAKE BY EARLY THURSDAY BEFORE WASHING OUT. THEN
A STRONGER COLD FRONT WILL PUSH DOWN THE LAKE ON FRIDAY...WITH A
TIGHTER PRESSURE GRADIENT AHEAD OF IT RESULTING IN STRONGER
SOUTHWEST WINDS. STABLE CONDITIONS WILL KEEP GUSTINESS DOWN EXCEPT
FOR THE NEAR SHORE WATERS WHERE GUSTS NEAR AROUND 25 KT ARE
POSSIBLE FRIDAY AFTERNOON. BEHIND THE FRONT...MODEST COLD
ADVECTION WILL BRING A PERIOD OF GUSTY NORTHERLY WINDS
SATURDAY...FOLLOWED BY HIGH PRESSURE QUICKLY BUILDING IN AND
LIGHTER WINDS FOR SUNDAY.
THE NEAR SHORE WATERS WILL SEE DIURNAL LAKE BREEZE INFLUENCE SIMILAR
TO TODAY ON WEDNESDAY BUT THEN ON THURSDAY...STRONGER WINDS ABOVE
THE SURFACE SHOULD LARGELY PREVENT THE DEVELOPMENT OF A LAKE BREEZE.
RC
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
132 PM CDT TUE JUL 16 2013
.DISCUSSION...
939 AM CDT
GOING FORECAST LOOKS TO BE IN GOOD SHAPE WITH NO BIG CHANGES
PLANNED AT THIS TIME...JUST A SLIGHT UPWARD ADJUSTMENT TO POPS.
MORNING SOUNDINGS AGAIN TODAY WERE VERY MOIST IN THE LOW LEVELS
THOUGH SLIGHTLY DRIER ABOVE 700MB AS COMPARED WITH YESTERDAY. PWATS
ARE DOWN ABOUT A QUARTER TO A HALF INCH OR FROM YESTERDAY`S LEVELS
BUT REMAIN 150% OR MORE OF AVERAGE. STRONG UPPER RIDGE HAS SHIFTED
WEST A BIT FROM YESTERDAYS POSITION WITH 500MB HEIGHTS 20-30 METERS
HIGHER THAN YESTERDAY. MID LEVEL TEMPS REMAIN VERY WARM WITH WEAK
MID LEVEL LAPSE RATES...HOWEVER ILX/DVN MORNING RAOBS AND ACARS OUT
OF MDW THIS MORNING SHOW NO INVERSION OR POTENTIAL CAPPING LAYER. SO
WHILE WE DONT HAVE ANY SHORTWAVE ALOFT TO PROVIDE FORCING LIKE
YESTERDAY AND WHILE PWATS ARE DOWN A BIT...STILL THINK ISOLATED
CONVECTION IS A DECENT BET TODAY. BOTH THE RUC FORECAST SOUNDINGS
AND MODIFIED OBSERVED SOUNDINGS SUGGEST MLCAPE VALUES REACHING
3000-3500 J/KG WITH LITTLE/NO INHIBITION.
AS MENTIONED THERE IS NO FORCING ALOFT TODAY AS WE SIT PARKED ALMOST
DIRECTLY UNDER THE UPPER RIDGE...HOWEVER VWP SHOWS SOUTHWEST WINDS
OFF THE DECK DIMINISHING FROM THE NOCTURNAL MAXIMA AND THINK WE
SHOULD ONCE AGAIN SEE A LAKE BREEZE FORM THIS AFTERNOON. GIVEN THE
LOW LFC`S THE SHALLOW FORCING ALONG THE LAKE BREEZE WITH NO CAP
SHOULD ONCE AGAIN BE ENOUGH TO KICK OFF ISOLATED TO WIDELY SCATTERED
AFTERNOON THUNDERSTORMS. ALREADY SEEING VERY HEALTHY CUMULUS FIELD
BLOSSOMING NEAR THE CONVERGENCE ZONE DOWNTOWN...SO GIVEN THE SET UP
AM PLANNING TO BUMP UP POPS SOME TODAY OVER LAKE AND COOK COUNTIES
IN ILLINOIS LATE THIS MORNING INTO THE AFTERNOON. THE SLIGHTLY DRIER
AIR ALOFT TODAY ALONG WITH SLIGHTLY STRONGER INSTABILITY ACTUALLY
RAISES THE MICROBURST THREAT SOME OVER YESTERDAY AND THINK THE
THREAT OF A PULSE SEVERE THUNDERSTORM IS A BIT GREATER TODAY.
WILL GET SOME UPDATED GRIDS WITH SLIGHTLY HIGHER POPS OUT ALONG THE
LAKE BREEZE SHORTLY.
IZZI
//PREV DISCUSSION...
337 AM CDT
FORECAST FOCUS REMAINS ON HEAT/HUMIDITY OVER THE NEXT SEVERAL
DAYS...AND POTENTIAL FOR ISOLATED THUNDERSTORMS AGAIN THIS
AFTERNOON. HEAT HEADLINES MAY BE REQUIRED LATER IN THE WEEK FOR
CONSECUTIVE DAYS OF PEAK HEAT INDICES ABOVE 100.
00Z RAOB ANALYSIS DEPICTS 6000 METER 500MB HEIGHTS AT ILN...WITH
UPPER LEVEL RIDGE EXPECTED TO DRIFT ACROSS NORTHERN INDIANA LATER
TODAY AND ACROSS CENTRAL IL ON WEDNESDAY...BEFORE GRADUALLY
WEAKENING AND SHIFTING SOUTH ACROSS THE LOWER OHIO VALLEY LATE IN IN
THE WEEK. 850MB TEMPS OF +18/19C SAMPLED BENEATH THE RIDGE...WITH
MODEL FORECASTS INDICATING THESE SLOWLY WARMING AS THE RIDGE DRIFTS
WEST...REACHING +20/21C BY FRIDAY AS THE RIDGE DRIFTS SOUTH AND
WEST-SOUTHWEST LOW LEVEL FLOW ENHANCES WARM ADVECTION OFF THE
PLAINS. TEMPS MONDAY WERE GENERALLY 89-91 OUTSIDE OF THE LAKE BREEZE
AND THUNDERSTORM EFFECTS...AND DIAGNOSIS OF LOW LEVEL THERMAL FIELDS
FROM MODELS INDICATE WE SHOULD BE PERHAPS A DEGREE OR SO HIGHER
OVERALL TODAY...AND IN THE LOW-MID 90S WED-FRI. COMBINED WITH SFC
DEW POINT TEMPERATURES GENERALLY IN THE LOWER 70S...THE COMBINATION
OF HEAT/HUMIDITY SHOULD YIELD AFTERNOON PEAK HEAT INDEX VALUES
ROUGHLY 98-102 DEGREES FOR THE NEXT FOUR DAYS. MUGGY CONDITIONS WITH
NIGHTTIME TEMPS SLOWLY FALLING THROUGH THE MID/UPPER 70S WILL NOT
PROVIDE MUCH RELIEF AT NIGHT EITHER. THREE TO FOUR CONSECUTIVE DAYS
OF THESE CONDITIONS WOULD REQUIRE HEAT HEADLINES FOR THE CWA. THE
CAVEATS AT THIS TIME HOWEVER REMAINS THE POTENTIAL FOR ISOLATED
AFTERNOON THUNDERSTORMS AGAIN TODAY (AND WED/THU AS WELL) AND A
GREATER THREAT OF THUNDERSTORMS FRIDAY AFTERNOON WHICH COULD DISRUPT
TEMPS/HEAT INDEX VALUES DURING PEAK HEATING...AS WELL AS LOWERING
DEW POINT TEMPERATURES DURING AFTERNOON MIXING. WILL HOLD OFF ON
HOISTING ANY HEADLINES FOR NOW...AND MONITOR HOW THINGS PLAY OUT
THIS AFTERNOON.
SHIFTING TO THUNDERSTORM POTENTIAL...FORECAST SOUNDINGS CONTINUE TO
DEPICT UNSTABLE AND FAIRLY UNCAPPED THERMODYNAMIC PROFILES ACROSS
THE AREA AGAIN THIS AFTERNOON. WHILE NOT MUCH SUPPORT NOTED ON THE
LARGE SCALE...LACK OF SIGNIFICANT CAPPING DOES SUGGEST THE POTENTIAL
FOR AT LEAST A FEW ISOLATED THUNDERSTORMS THIS AFTERNOON
PARTICULARLY ACROSS NORTHERN PARTS OF THE IL CWA...WITH CONVERGENCE
ALONG WEAK LAKE BREEZE A POTENTIAL TRIGGER. CONVECTIVE OUTFLOW
BOUNDARIES FROM ANY ISOLATED STORMS THAT DO FORM WOULD ALSO PROVIDE
FOCUS FOR ADDITIONAL ISOLATED DEVELOPMENT...WHICH SHOULD WANE TOWARD
EVENING WITH LOSS OF DIURNAL COMPONENT OF INSTABILITY. THOUGH SPARSE
IN NUMBER AND COVERAGE...ANY STORMS THAT WOULD FORM WOULD LIKELY BE
SLOW-MOVING AND POTENTIALLY HEAVY RAIN PRODUCERS...WITH 2.03 INCH
PWAT NOTED IN DVN 00Z RAOB AND 1.90 INCHES AT ILX. WHILE AN ISOLATED
THUNDERSTORM MAY ALSO BE POSSIBLE WEDNESDAY AND THURSDAY
AFTERNOON...THE POTENTIAL SHOULD BE DECREASING AS THE RIDGE DRIFTS
CLOSER AND MID-LEVEL TEMPERATURES WARM. ALSO...IT APPEARS AS THOUGH
THERE WILL BE JUST ENOUGH WEST-SOUTHWEST FLOW IN LOW LEVELS AFTER
TODAY TO PREVENT THE LAKE BREEZE FROM MOVING INLAND...PROVIDING LESS
FOCUS FOR CONVECTIVE INITIATION.
AS INDICATED ABOVE...THE UPPER RIDGE IS ANTICIPATED TO WEAKEN AND
MOVE SOUTH THURSDAY AND FRIDAY...WITH MID/UPPER LEVEL WESTERLIES
SETTLING ACROSS THE UPPER MIDWEST. MODEL GUIDANCE REMAINS IN GOOD
AGREEMENT THAT AMPLIFICATION OF AN UPPER TROUGH WILL OCCUR ACROSS
CENTRAL CANADA AND THE UPPER MIDWEST BY FRIDAY NIGHT...WITH A COLD
FRONT SAGGING SOUTH INTO OUR AREA. THUNDERSTORM POTENTIAL LOOKS TO
INCREASE FRIDAY AFTERNOON AHEAD OF THE FRONT...AS LARGE SCALE ASCENT
DEVELOPS IN ADVANCE OF THE DEEPENING UPPER TROUGH AND LOW LEVEL
CONVERGENCE AND MOISTURE POOLING OCCUR ALONG AND SOUTH OF THE COLD
FRONTAL BOUNDARY. SOME LINGERING THREAT OF SHOWERS/THUNDERSTORMS MAY
LINGER INTO SATURDAY AS THE FRONT CONTINUES TO SAG SOUTHWARD...
THOUGH MAINLY ACROSS THE SOUTH/SOUTHEASTERN PARTS OF THE CWA. COOLER
AND LESS HUMID WEATHER CAN BE EXPECTED HOWEVER...AS HIGH PRESSURE
BUILDS SOUTHEAST ACROSS THE GREAT LAKES OVER THE WEEKEND AND SHIFTS
WINDS TO THE NORTH-NORTHEAST. A RETURN TO WARMER AND MORE HUMID
CONDITIONS LOOKS TO TAKE PLACE AGAIN EARLY NEXT WEEK HOWEVER...WITH
THE ECMWF QUICKER WITH THE RETURN MONDAY.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* LAKE BREEZE POTENTIAL AND TIMING MID TO LATE THIS AFTERNOON.
* WIDELY SCATTERED THUNDERSTORMS DEVELOPING EARLY TO MID THIS
AFTERNOON.
BMD
//DISCUSSION...UPDATED 18Z...
CONCERNS FOR A LAKE BREEZE THIS AFTERNOON AND A WIND SHIFT DUE TO A
LAKE BREEZE CONTINUE THIS AFTERNOON. THE AREA REMAINS UNDER A VERY
UNSTABLE AND WEAKLY CAPPED AIRMASS. WEAK MID LEVEL LAPSE RATES AND
LACK OF ANY UPPER LEVEL SUPPORT HAVE INHIBITED DEEP CONVECTION THUS
FAR...BUT MODIFIED NAM/AMDAR SHOW THAT WITH ONLY A LITTLE MORE
SURFACE HEATING...DEEP CONVECTION/THUNDERSTORM DEVELOPMENT REMAINS A
DISTINCT POSSIBILITY. LACK OF ANY SYNOPTIC FORCING MAY KEEP COVERAGE
ON THE LOW END...BUT THE LAKE BREEZE STILL APPEARS TO BE THE BEST
FOCUS...AND ANY THUNDERSTORMS THAT DO DEVELOP WILL LIKELY BE SLOW
MOVING AND PULSY.
THE LAKE BREEZE HAS BEEN SLOW TO DEVELOP WITH MODEST SOUTHWEST FLOW
IN PLACE...BUT SENSORS IN DOWNTOWN CHICAGO AND AT THE CHICAGO CRIB A
FEW MILES OFF SHORE HAVE SHOWN HINTS OF IT TRYING TO BECOME BETTER
ORGANIZED...INCLUDING THE NORTHERLY ISLAND SENSOR RECENTLY TURNING
E. PUSHED BACK THE TIMING WHICH IS IN LINE WITH LATEST RAP/HRRR RUNS
THOUGH CONFIDENCE ON REACHING THE TERMINALS IS LESS THAN BEFORE.
OVERNIGHT...LIGHT SOUTHWESTERLY WINDS WILL TAKE OVER AGAIN. MUGGY
AIRMASS REMAINS IN PLACE AND COOLING WILL LEAD TO MODEST REDUCTIONS
IN VSBY DUE TO MIST/HAZE.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* LOW TO MEDIUM CONFIDENCE IN LAKE BREEZE TIMING/REACHING TERMINALS.
* MEDIUM CONFIDENCE IN THUNDERSTORMS...COVERAGE SHOULD REMAIN
RELATIVELY LOW SO CONFIDENCE IN THUNDERSTORMS HITTING TERMINALS
IS LOW.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...MVFR VISIBILITY OVERNIGHT DUE TO BR HZ.
OTHERWISE...VFR...NO SIG WX.
THURSDAY...POSSIBLE MVFR VISIBILITY EARLY MORNING AND LATE
OVERNIGHT DUE TO BR HZ. OTHERWISE...VFR...NO SIG WX.
FRIDAY...INCREASING CHANCES OF TS AS DAY PROGRESSES...FROM SLIGHT
CHANCE IN THE MORNING TO CHANCE IN AFTERNOON AND LIKELY FRIDAY
NIGHT. ANY TSRA WOULD PRODUCE OF MVFR AND POSSIBLY BRIEF IFR
CONDITIONS.
SATURDAY...SLIGHT CHANCE OF TS. OTHERWISE VFR.
SUNDAY...VFR...NO SIG WX.
MONDAY...CHANCE OF TSRA...OTHERWISE VFR.
&&
.MARINE...
339 AM CDT
A LARGE AREA OF HIGH PRESSURE CENTERED OVER THE OH VALLEY EARLY
THIS MORNING WILL CONTINUE TO SLOWLY SHIFT TO THE W AND WILL BE
CENTERED IN THE MID MS VALLEY BY WED NIGHT MAINTAINING LIGHT TO
GENTLE S TO SW BREEZES ON THE LAKE. DURING THU AND THU NIGHT SW
WINDS WILL GRADUALLY FRESHEN AS A COLD FRONT DROPS S ACROSS THE
N WOODS AND LAKE SUPERIOR WHERE IT WILL WEAKEN. A STRONGER COLD
FRONT WILL DROP S OVER NORTHERN LAKE MI DURING FRI AFTERNOON
WITH THE COLD FRONT CONTINUING S DOWN THE LAKE REACHING THE S
END BY DAWN SAT. HIGH PRESSURE BUILDING SE FROM CENTRAL CANADA
TO THE UPPER MIDWEST DURING FRI NIGHT AND SAT WILL MAINTAIN
GENTLE TO MODERATE N TO NE BREEZES THROUGH THAT PERIOD.
TRS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1106 AM CDT TUE JUL 16 2013
.DISCUSSION...
939 AM CDT
GOING FORECAST LOOKS TO BE IN GOOD SHAPE WITH NO BIG CHANGES
PLANNED AT THIS TIME...JUST A SLIGHT UPWARD ADJUSTMENT TO POPS.
MORNING SOUNDINGS AGAIN TODAY WERE VERY MOIST IN THE LOW LEVELS
THOUGH SLIGHTLY DRIER ABOVE 700MB AS COMPARED WITH YESTERDAY. PWATS
ARE DOWN ABOUT A QUARTER TO A HALF INCH OR FROM YESTERDAY`S LEVELS
BUT REMAIN 150% OR MORE OF AVERAGE. STRONG UPPER RIDGE HAS SHIFTED
WEST A BIT FROM YESTERDAYS POSITION WITH 500MB HEIGHTS 20-30 METERS
HIGHER THAN YESTERDAY. MID LEVEL TEMPS REMAIN VERY WARM WITH WEAK
MID LEVEL LAPSE RATES...HOWEVER ILX/DVN MORNING RAOBS AND ACARS OUT
OF MDW THIS MORNING SHOW NO INVERSION OR POTENTIAL CAPPING LAYER. SO
WHILE WE DONT HAVE ANY SHORTWAVE ALOFT TO PROVIDE FORCING LIKE
YESTERDAY AND WHILE PWATS ARE DOWN A BIT...STILL THINK ISOLATED
CONVECTION IS A DECENT BET TODAY. BOTH THE RUC FORECAST SOUNDINGS
AND MODIFIED OBSERVED SOUNDINGS SUGGEST MLCAPE VALUES REACHING
3000-3500 J/KG WITH LITTLE/NO INHIBITION.
AS MENTIONED THERE IS NO FORCING ALOFT TODAY AS WE SIT PARKED ALMOST
DIRECTLY UNDER THE UPPER RIDGE...HOWEVER VWP SHOWS SOUTHWEST WINDS
OFF THE DECK DIMINISHING FROM THE NOCTURNAL MAXIMA AND THINK WE
SHOULD ONCE AGAIN SEE A LAKE BREEZE FORM THIS AFTERNOON. GIVEN THE
LOW LFC`S THE SHALLOW FORCING ALONG THE LAKE BREEZE WITH NO CAP
SHOULD ONCE AGAIN BE ENOUGH TO KICK OFF ISOLATED TO WIDELY SCATTERED
AFTERNOON THUNDERSTORMS. ALREADY SEEING VERY HEALTHY CUMULUS FIELD
BLOSSOMING NEAR THE CONVERGENCE ZONE DOWNTOWN...SO GIVEN THE SET UP
AM PLANNING TO BUMP UP POPS SOME TODAY OVER LAKE AND COOK COUNTIES
IN ILLINOIS LATE THIS MORNING INTO THE AFTERNOON. THE SLIGHTLY DRIER
AIR ALOFT TODAY ALONG WITH SLIGHTLY STRONGER INSTABILITY ACTUALLY
RAISES THE MICROBURST THREAT SOME OVER YESTERDAY AND THINK THE
THREAT OF A PULSE SEVERE THUNDERSTORM IS A BIT GREATER TODAY.
WILL GET SOME UPDATED GRIDS WITH SLIGHTLY HIGHER POPS OUT ALONG THE
LAKE BREEZE SHORTLY.
IZZI
//PREV DISCUSSION...
337 AM CDT
FORECAST FOCUS REMAINS ON HEAT/HUMIDITY OVER THE NEXT SEVERAL
DAYS...AND POTENTIAL FOR ISOLATED THUNDERSTORMS AGAIN THIS
AFTERNOON. HEAT HEADLINES MAY BE REQUIRED LATER IN THE WEEK FOR
CONSECUTIVE DAYS OF PEAK HEAT INDICES ABOVE 100.
00Z RAOB ANALYSIS DEPICTS 6000 METER 500MB HEIGHTS AT ILN...WITH
UPPER LEVEL RIDGE EXPECTED TO DRIFT ACROSS NORTHERN INDIANA LATER
TODAY AND ACROSS CENTRAL IL ON WEDNESDAY...BEFORE GRADUALLY
WEAKENING AND SHIFTING SOUTH ACROSS THE LOWER OHIO VALLEY LATE IN IN
THE WEEK. 850MB TEMPS OF +18/19C SAMPLED BENEATH THE RIDGE...WITH
MODEL FORECASTS INDICATING THESE SLOWLY WARMING AS THE RIDGE DRIFTS
WEST...REACHING +20/21C BY FRIDAY AS THE RIDGE DRIFTS SOUTH AND
WEST-SOUTHWEST LOW LEVEL FLOW ENHANCES WARM ADVECTION OFF THE
PLAINS. TEMPS MONDAY WERE GENERALLY 89-91 OUTSIDE OF THE LAKE BREEZE
AND THUNDERSTORM EFFECTS...AND DIAGNOSIS OF LOW LEVEL THERMAL FIELDS
FROM MODELS INDICATE WE SHOULD BE PERHAPS A DEGREE OR SO HIGHER
OVERALL TODAY...AND IN THE LOW-MID 90S WED-FRI. COMBINED WITH SFC
DEW POINT TEMPERATURES GENERALLY IN THE LOWER 70S...THE COMBINATION
OF HEAT/HUMIDITY SHOULD YIELD AFTERNOON PEAK HEAT INDEX VALUES
ROUGHLY 98-102 DEGREES FOR THE NEXT FOUR DAYS. MUGGY CONDITIONS WITH
NIGHTTIME TEMPS SLOWLY FALLING THROUGH THE MID/UPPER 70S WILL NOT
PROVIDE MUCH RELIEF AT NIGHT EITHER. THREE TO FOUR CONSECUTIVE DAYS
OF THESE CONDITIONS WOULD REQUIRE HEAT HEADLINES FOR THE CWA. THE
CAVEATS AT THIS TIME HOWEVER REMAINS THE POTENTIAL FOR ISOLATED
AFTERNOON THUNDERSTORMS AGAIN TODAY (AND WED/THU AS WELL) AND A
GREATER THREAT OF THUNDERSTORMS FRIDAY AFTERNOON WHICH COULD DISRUPT
TEMPS/HEAT INDEX VALUES DURING PEAK HEATING...AS WELL AS LOWERING
DEW POINT TEMPERATURES DURING AFTERNOON MIXING. WILL HOLD OFF ON
HOISTING ANY HEADLINES FOR NOW...AND MONITOR HOW THINGS PLAY OUT
THIS AFTERNOON.
SHIFTING TO THUNDERSTORM POTENTIAL...FORECAST SOUNDINGS CONTINUE TO
DEPICT UNSTABLE AND FAIRLY UNCAPPED THERMODYNAMIC PROFILES ACROSS
THE AREA AGAIN THIS AFTERNOON. WHILE NOT MUCH SUPPORT NOTED ON THE
LARGE SCALE...LACK OF SIGNIFICANT CAPPING DOES SUGGEST THE POTENTIAL
FOR AT LEAST A FEW ISOLATED THUNDERSTORMS THIS AFTERNOON
PARTICULARLY ACROSS NORTHERN PARTS OF THE IL CWA...WITH CONVERGENCE
ALONG WEAK LAKE BREEZE A POTENTIAL TRIGGER. CONVECTIVE OUTFLOW
BOUNDARIES FROM ANY ISOLATED STORMS THAT DO FORM WOULD ALSO PROVIDE
FOCUS FOR ADDITIONAL ISOLATED DEVELOPMENT...WHICH SHOULD WANE TOWARD
EVENING WITH LOSS OF DIURNAL COMPONENT OF INSTABILITY. THOUGH SPARSE
IN NUMBER AND COVERAGE...ANY STORMS THAT WOULD FORM WOULD LIKELY BE
SLOW-MOVING AND POTENTIALLY HEAVY RAIN PRODUCERS...WITH 2.03 INCH
PWAT NOTED IN DVN 00Z RAOB AND 1.90 INCHES AT ILX. WHILE AN ISOLATED
THUNDERSTORM MAY ALSO BE POSSIBLE WEDNESDAY AND THURSDAY
AFTERNOON...THE POTENTIAL SHOULD BE DECREASING AS THE RIDGE DRIFTS
CLOSER AND MID-LEVEL TEMPERATURES WARM. ALSO...IT APPEARS AS THOUGH
THERE WILL BE JUST ENOUGH WEST-SOUTHWEST FLOW IN LOW LEVELS AFTER
TODAY TO PREVENT THE LAKE BREEZE FROM MOVING INLAND...PROVIDING LESS
FOCUS FOR CONVECTIVE INITIATION.
AS INDICATED ABOVE...THE UPPER RIDGE IS ANTICIPATED TO WEAKEN AND
MOVE SOUTH THURSDAY AND FRIDAY...WITH MID/UPPER LEVEL WESTERLIES
SETTLING ACROSS THE UPPER MIDWEST. MODEL GUIDANCE REMAINS IN GOOD
AGREEMENT THAT AMPLIFICATION OF AN UPPER TROUGH WILL OCCUR ACROSS
CENTRAL CANADA AND THE UPPER MIDWEST BY FRIDAY NIGHT...WITH A COLD
FRONT SAGGING SOUTH INTO OUR AREA. THUNDERSTORM POTENTIAL LOOKS TO
INCREASE FRIDAY AFTERNOON AHEAD OF THE FRONT...AS LARGE SCALE ASCENT
DEVELOPS IN ADVANCE OF THE DEEPENING UPPER TROUGH AND LOW LEVEL
CONVERGENCE AND MOISTURE POOLING OCCUR ALONG AND SOUTH OF THE COLD
FRONTAL BOUNDARY. SOME LINGERING THREAT OF SHOWERS/THUNDERSTORMS MAY
LINGER INTO SATURDAY AS THE FRONT CONTINUES TO SAG SOUTHWARD...
THOUGH MAINLY ACROSS THE SOUTH/SOUTHEASTERN PARTS OF THE CWA. COOLER
AND LESS HUMID WEATHER CAN BE EXPECTED HOWEVER...AS HIGH PRESSURE
BUILDS SOUTHEAST ACROSS THE GREAT LAKES OVER THE WEEKEND AND SHIFTS
WINDS TO THE NORTH-NORTHEAST. A RETURN TO WARMER AND MORE HUMID
CONDITIONS LOOKS TO TAKE PLACE AGAIN EARLY NEXT WEEK HOWEVER...WITH
THE ECMWF QUICKER WITH THE RETURN MONDAY.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* TIMING PASSAGE OF LAKE BREEZE AND WIND DIRECTION BEHIND BOUNDARY.
* POTENTIAL FOR SCATTERED TSRA...PARTICULARLY ALONG THE LAKE
BREEZE WHERE THE BEST CONVERGENCE WILL OCCUR...BUT ISOLATED
FARTHER INLAND.
* VSBY REDUCTION DUE TO BR/HZ EARLY WEDNESDAY MORNING.
BMD
//DISCUSSION...UPDATED 12Z...
VERY SLOW WESTWARD RETROGRESSION OF THE UPPER PATTERN ACROSS
THE EASTERN AND CENTRAL U.S WILL CONTINUE TODAY...THEN TO THE
WEST-SOUTHWEST TONIGHT. THE W TO E ELONGATED UPPER ANTICYCLONE
THAT CURRENTLY IS OVER FAR WESTERN LOWER MI IS TO RETREAT TO
AROUND THE CENTRAL PORTION OF THE IL-IN BOARDER BY LATE TONIGHT.
THE ASSOCIATED SURFACE HIGH CENTER IS ALSO DRIFTING WESTWARD
RESULTING IN THE LOW LEVEL FLOW OVER THE AREA BACKING FROM
SOUTHEASTERLY TO SOUTHWESTERLY OVERNIGHT PER WIND PROFILES FROM
WSR-88D NETWORK AS WELL AS TERMINAL DOPPLER INSTALLATIONS.
THIS SW FLOW WILL BE RATHER WEAK WITH PROGGED MIXED LAYER WINDS
OF ONLY UP TO AROUND 10 KT AT MOST DURING THE DAY. WHILE WEAK IT
IS EXPECTED TO LIMIT ANY LAKE BREEZE INLAND PENETRATION TO JUST
ALONG THE IMMEDIATE SHORELINES OF NW IN AND UP TO AROUND DOWNTOWN
CHICAGO...WITH DEEPER PENETRATION INLAND THE FURTHER ONES GOES
FROM THE LOOP N UP TO SE WI. EVEN MODELS THAT ARE MOST AGGRESSIVE
WITH THE LAKE BREEZE ONLY TAKE IT AS FAR W AS THE EASTERN BOARDER
OF THE ORD AIR FIELD SO THE TAFOR MAINTAINS SW SURFACE WINDS
THROUGH THE DAY.
WITH SOMEWHAT STAGNANT CONDITIONS UNDER THE ANTICYCLONE AN
INCREASE IN PARTICULATE MATTER AND COUPLED WITH DEW POINTS
REMAINING IN THE LOWER 70S IS EXPECTED TO RESULT IN VISIBILITY
BEING RESTRICTED BY SMOG FROM LATE OVERNIGHT TIL A COUPLE HOURS
AFTERN SUNRISE WED. DO NOT ANTICIPATE PREVAILING VISIBILITY
CONDITIONS AT ORD OR MDW TO BE BELOW MVFR THOUGH POSSIBLE IT MAY
DIP INTO HIGHER END OF IFR AROUND SUNRISE.
TRS
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH CONFIDENCE IN LAKE BREEZE DEVELOPING AND AT LEAST MOVING
INTO THE VICINITY OF THE TERMINALS...MEDIUM CONFIDENCE ON
REACHING TERMINALS AND TURNING WINDS EASTERLY.
* MEDIUM CONFIDENCE IN WIDELY SCATTERED TSRA ESPECIALLY ALONG LAKE
BREEZE. LOW CONFIDENCE IN SPECIFIC IMPACTS TO TERMINALS.
* MEDIUM CONFIDENCE IN VSBY RESTRICTION EARLY WEDNESDAY MORNING.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...MVFR VISIBILITY OVERNIGHT DUE TO BR HZ.
OTHERWISE...VFR...NO SIG WX.
THURSDAY...POSSIBLE MVFR VISIBILITY EARLY MORNING AND LATE
OVERNIGHT DUE TO BR HZ. OTHERWISE...VFR...NO SIG WX.
FRIDAY...INCREASING CHANCES OF TS AS DAY PROGRESSES...FROM SLIGHT
CHANCE IN THE MORNING TO CHANCE IN AFTERNOON AND LIKELY FRIDAY
NIGHT. ANY TSRA WOULD PRODUCE OF MVFR AND POSSIBLY BRIEF IFR
CONDITIONS.
SATURDAY...SLIGHT CHANCE OF TS. OTHERWISE VFR.
SUNDAY...VFR...NO SIG WX.
MONDAY...CHANCE OF TSRA...OTHERWISE VFR.
&&
.MARINE...
339 AM CDT
A LARGE AREA OF HIGH PRESSURE CENTERED OVER THE OH VALLEY EARLY
THIS MORNING WILL CONTINUE TO SLOWLY SHIFT TO THE W AND WILL BE
CENTERED IN THE MID MS VALLEY BY WED NIGHT MAINTAINING LIGHT TO
GENTLE S TO SW BREEZES ON THE LAKE. DURING THU AND THU NIGHT SW
WINDS WILL GRADUALLY FRESHEN AS A COLD FRONT DROPS S ACROSS THE
N WOODS AND LAKE SUPERIOR WHERE IT WILL WEAKEN. A STRONGER COLD
FRONT WILL DROP S OVER NORTHERN LAKE MI DURING FRI AFTERNOON
WITH THE COLD FRONT CONTINUING S DOWN THE LAKE REACHING THE S
END BY DAWN SAT. HIGH PRESSURE BUILDING SE FROM CENTRAL CANADA
TO THE UPPER MIDWEST DURING FRI NIGHT AND SAT WILL MAINTAIN
GENTLE TO MODERATE N TO NE BREEZES THROUGH THAT PERIOD.
TRS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS DODGE CITY KS
333 PM CDT TUE JUL 16 2013
...UPDATE TO LONG TERM DISCUSSION...
.SYNOPSIS...
ISSUED AT 1201 PM CDT TUE JUL 16 2013
AT 12Z TUESDAY A 500MB LOW WAS LOCATED OVER EASTERN NEW MEXICO
AND A 500MB HIGH WAS LOCATED OVER THE OHIO VALLEY. ACROSS THE
SOUTHERN AND CENTRAL PLAINS A SOUTHEAST FLOW IN THE 850MB TO 500MB
LEVEL WAS DRAWING HIGHER DEWPOINTS INTO WESTERN KANSAS. ONE UPPER
LEVEL DISTURBANCE ROTATING AROUND THIS UPPER LOW WAS LOCATED
ACROSS THE PANHANDLE OF TEXAS AND WESTERN OKLAHOMA AS OF 12Z
TUESDAY WITH ANOTHER DISTURBANCE LOCATED NEAR THE BASED OF THIS
UPPER LOW ACROSS WESTERN TEXAS. WATER VAPOR LOOP AS OF 15Z
INDICATED THIS UPPER LOW WAS MOVING SLOWLY WESTWARD AS THE
PANHANDLE UPPER LEVEL WAVE APPROACHES SOUTHWEST KANSAS.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 159 PM CDT TUE JUL 16 2013
RAP AND WATER VAPOR LOOP INDICATING AN UPPER LEVEL DISTURBANCE
WAS MOVING NORTHWEST ACROSS THE PANHANDLE OF TEXAS AS OF 19Z WITH
RADAR TRENDS INDICATING PRECIPITATION INCREASING IN AREA COVER
AHEAD OF THIS DISTURBANCE ACROSS PORTIONS OF SOUTHWEST KANSAS. NAM
AND RAP WERE IN DECENT AGREEMENT IN MOVING THIS UPPER WAVE ACROSS
SOUTHWEST KANSAS INTO SOUTHEAST COLORADO EARLY TONIGHT. GIVEN THE
MOISTURE FORECAST ACROSS SOUTHWEST KANSAS IN THE 850MB TO 500MB
AHEAD OF THIS UPPER SYSTEM WILL RETAIN AT LEAST A CHANCE FOR
SHOWERS ACROSS SOUTHWEST KANSAS AT AROUND 03Z AND THEN TAPER
PRECIPITATION OFF FROM NORTHEAST TO SOUTHWEST.
AFTER MIDNIGHT SUBSIDENCE APPEARS TO DEVELOP ACROSS WESTERN KANSAS
AS THE UPPER LEVEL DISTURBANCE MOVES INTO SOUTHERN COLORADO.
CLEARING SKIES MAY BRIEFLY DEVELOP AFTER MIDNIGHT, HOWEVER SOME
EARLY MORNING STATUS AND/OR FOG WILL BE POSSIBLE AROUND DAYBREAK
GIVEN THE SHALLOW LAYER OF LOW LEVEL MOISTURE FORECAST BY THE 12Z
NAM. BASED ONE THE EXPECTED DEWPOINTS OVERNIGHT THE PREVIOUS
FORECAST WITH LOWS RANGING FROM 60 TO NEAR 65 DEGREES STILL LOOKS
ON TRACK.
ON WEDNESDAY A TROUGH OF LOW PRESSURE WILL DEEPEN ALONG THE LEE
OF THE ROCKIES. BASED ON EXPECTED SKY COVER AND 00Z 850MB
TEMPERATURES RANGING FROM AROUND 20 IN SOUTH CENTRAL KANSAS TO THE
MID 20S NEAR THE COLORADO BORDER HAVE DECIDED TO TREND TOWARDS THE
SLIGHTLY COOLER ECMWF GUIDANCE FOR HIGHS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 333 PM CDT TUE JUL 16 2013
WEDNESDAY NIGHT:
LEE TROUGHING WILL CONTINUE WEDNESDAY NIGHT INTO THURSDAY MORNING.
THE UPPER LEVEL DISTURBANCE MENTIONED IN THE SYNOPSIS/SHORT TERM PERIOD
WILL CONTINUE TO DRIFT WELL AWAY FROM THE REGION BY THURSDAY MORNING.
STILL, THERE WILL BE "COOLER" LOW TO MID LEVEL TEMPERATURES ASSOCIATED
WITH THE PRESSURE PERTURBATION LINGERING ACROSS THE REGION. CONSIDERING
THIS AND THE WARM BIAS SHOWN VIA BOISE VERIFICATION...HAVE GONE WITH
COOLER MOS GUIDANCE FOR MINIMUMS INTO THURSDAY MORNING...60S DEG F.
THURSDAY:
ON THURSDAY, THE AFOREMENTIONED LEE SURFACE TROUGH WILL CONTINUE TO
DEEPEN AHEAD OF A TRAVERSING SHORTWAVE TROF ACROSS THE NORTHERN PLAINS.
THIS WILL ALLOW FOR A CONTINUED WARM AIR ADVECTION REGIME THROUGH THE
DAY. HAVE GONE WITH COOLER ECMWF RAW OUTPUT FOR MAXIMUMS - MID 90S DEG
F NORTHEAST TO AROUND 90 DEG F SOUTHWEST. NO PRECIPITATION IS EXPECTED
THROUGH THE DAY WITH PRECIPITATION PROBABILITY PERCENTAGE POINTS AOB
10 PERCENT AS THE AFOREMENTIONED SYNOPTIC SYSTEM IS WELL TO THE NORTH.
FRIDAY AND BEYOND:
A MODERATION OF TEMPERATURES IS EXPECTED WITH MAXIMUMS IN THE 90S DEG
F AND LOWS IN THE 60S AND 70S DEG F AS LEE TROUGHING CONTINUES AHEAD
OF AN APPROACHING COLD FRONT. THIS FRONT SHOULD BE IN THE REGION (PER
ECMWF) SOMETIME LATE FRIDAY NIGHT AND INTO SATURDAY. CONVECTION WILL
BE POSSIBLE ALONG THIS DENSITY GRADIENT THROUGH THE WEEKEND. THE 12Z
ECMWF SOLUTION HAS TRENDED DRIER THAN COMPARED TO THE 00Z ECMWF SOLUTION.
THE GFS, AS PER USUAL, IS WETTER AND COOLER THAN COMPARED TO THE EC.
DUE TO THE UNCERTAINTY, WILL GO WITH THE ALLBLEND SOLUTION FOR NOW.
THIS MODEL - OF COURSE - APPLIES A WEIGHTING FUNCTION TO BOTH SOLUTIONS
PLUS THE PREVIOUS NDFD GRIDS. BEYOND THIS, 500 HPA RIDGING IS INDICATED
BY BOTH MODELS BY EARLY TO MID WEEK OF NEXT WEEK, WHICH FAVORS A DRY
FORECAST AND HOT TEMPERATURES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1201 PM CDT TUE JUL 16 2013
DDC 12Z SOUNDING, UPPER AIR ANALYSIS AND NAM BUFR SOUNDINGS
INDICATING A FAIRLY DEEP LAYER OF MOISTURE WILL BE PRESENT THROUGH
EARLY TONIGHT AT DDC AND GCK. AS A RESULT CLOUD BASES WILL
IMPROVE, HOWEVER MVFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH
AT LEAST 00Z WEDNESDAY. THE EXCEPTION WILL BE HAYS WERE BUFR
SOUNDINGS INDICATED VFR CONDITIONS WILL BE LIKELY THIS AFTERNOON
AND EARLY TONIGHT. THERE WILL ALSO BE A CHANCE FOR SHOWERS THIS
AFTERNOON AND EARLY TONIGHT, MAINLY IN THE GCK AND DDC AREA AS AN
UPPER LEVEL DISTURBANCE ROTATES AROUND AN UPPER LOW THAT WILL BE
LOCATED ACROSS EASTERN NEW MEXICO. SOUTHEAST WINDS AT AROUND 15KTS
WILL DECREASE TO 10KTS OR LESS AFTER SUNSET.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 62 87 65 91 / 40 10 10 0
GCK 60 86 64 90 / 50 10 10 10
EHA 59 82 62 88 / 50 10 10 10
LBL 62 84 64 89 / 60 10 10 10
HYS 63 89 67 94 / 20 10 0 0
P28 65 87 68 91 / 30 20 10 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...BURGERT
LONG TERM...3.14
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
205 PM CDT TUE JUL 16 2013
...UPDATED SHORT TERM DISCUSSION...
.SYNOPSIS...
ISSUED AT 1201 PM CDT TUE JUL 16 2013
AT 12Z TUESDAY A 500MB LOW WAS LOCATED OVER EASTERN NEW MEXICO
AND A 500MB HIGH WAS LOCATED OVER THE OHIO VALLEY. ACROSS THE
SOUTHERN AND CENTRAL PLAINS A SOUTHEAST FLOW IN THE 850MB TO 500MB
LEVEL WAS DRAWING HIGHER DEWPOINTS INTO WESTERN KANSAS. ONE UPPER
LEVEL DISTURBANCE ROTATING AROUND THIS UPPER LOW WAS LOCATED
ACROSS THE PANHANDLE OF TEXAS AND WESTERN OKLAHOMA AS OF 12Z
TUESDAY WITH ANOTHER DISTURBANCE LOCATED NEAR THE BASED OF THIS
UPPER LOW ACROSS WESTERN TEXAS. WATER VAPOR LOOP AS OF 15Z
INDICATED THIS UPPER LOW WAS MOVING SLOWLY WESTWARD AS THE
PANHANDLE UPPER LEVEL WAVE APPROACHES SOUTHWEST KANSAS.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 159 PM CDT TUE JUL 16 2013
RAP AND WATER VAPOR LOOP INDICATING AN UPPER LEVEL DISTURBANCE
WAS MOVING NORTHWEST ACROSS THE PANHANDLE OF TEXAS AS OF 19Z WITH
RADAR TRENDS INDICATING PRECIPITATION INCREASING IN AREA COVER
AHEAD OF THIS DISTURBANCE ACROSS PORTIONS OF SOUTHWEST KANSAS. NAM
AND RAP WERE IN DECENT AGREEMENT IN MOVING THIS UPPER WAVE ACROSS
SOUTHWEST KANSAS INTO SOUTHEAST COLORADO EARLY TONIGHT. GIVEN THE
MOISTURE FORECAST ACROSS SOUTHWEST KANSAS IN THE 850MB TO 500MB
AHEAD OF THIS UPPER SYSTEM WILL RETAIN AT LEAST A CHANCE FOR
SHOWERS ACROSS SOUTHWEST KANSAS AT AROUND 03Z AND THEN TAPER
PRECIPITATION OFF FROM NORTHEAST TO SOUTHWEST.
AFTER MIDNIGHT SUBSIDENCE APPEARS TO DEVELOP ACROSS WESTERN KANSAS
AS THE UPPER LEVEL DISTURBANCE MOVES INTO SOUTHERN COLORADO.
CLEARING SKIES MAY BRIEFLY DEVELOP AFTER MIDNIGHT, HOWEVER SOME
EARLY MORNING STATUS AND/OR FOG WILL BE POSSIBLE AROUND DAYBREAK
GIVEN THE SHALLOW LAYER OF LOW LEVEL MOISTURE FORECAST BY THE 12Z
NAM. BASED ONE THE EXPECTED DEWPOINTS OVERNIGHT THE PREVIOUS
FORECAST WITH LOWS RANGING FROM 60 TO NEAR 65 DEGREES STILL LOOKS
ON TRACK.
ON WEDNESDAY A TROUGH OF LOW PRESSURE WILL DEEPEN ALONG THE LEE
OF THE ROCKIES. BASED ON EXPECTED SKY COVER AND 00Z 850MB
TEMPERATURES RANGING FROM AROUND 20 IN SOUTH CENTRAL KANSAS TO THE
MID 20S NEAR THE COLORADO BORDER HAVE DECIDED TO TREND TOWARDS THE
SLIGHTLY COOLER ECMWF GUIDANCE FOR HIGHS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 350 AM CDT TUE JUL 16 2013
UPPER LEVEL RIDGING WILL STRENGTHEN OVER THE CENTRAL PLAINS
WEDNESDAY INTO THURSDAY, WITH LITTLE OR NO PRECIPITATION AND HIGH
TEMPERATURES RISING INTO THE 80S TO NEAR 90F WEDNESDAY AND INTO THE
90S BY THURSDAY. A LEFTOVER SHOWER OR TWO CANNOT BE COMPLETELY
RULED OUT WEDNESDAY IN SOUTHERN KANSAS SINCE THE MID LEVEL FLOW
WILL STILL BE SOUTHEASTERLY, WITH CONTINUED LOW TO MID LEVEL
MOISTURE INFLUX. A LEE TROUGH WILL BE IN PLACE ACROSS THE HIGH
PLAINS IN RESPONSE TO ZONAL MID LEVEL FLOW ACROSS THE NORTHERN
ROCKIES, LEADING TO SOUTH WINDS EACH DAY.
UPPER LEVEL TROUGHING WILL PROGRESS SOUTHEASTWARD THROUGH THE GREAT
LAKES BY FRIDAY, ALLOWING A COLD FRONT TO PUSH INTO NORTHWEST KANSAS
FRIDAY AFTERNOON AND THEN STALL OUT OVER KANSAS/OKLAHOMA BY
SATURDAY. THIS WILL SET THE STAGE FOR CHANCES OF SHOWERS AND
THUNDERSTORMS FROM LATE FRIDAY INTO SUNDAY GIVEN THAT THERE SHOULD
BE SUFFICIENT MOISTURE (DEWPOINTS IN THE 60S) FOR THUNDERSTORM
ACTIVITY. HIGH TEMPERATURES WILL BE IN THE MID 90S FRIDAY AHEAD OF
THE FRONT, BUT ONLY NEAR 90 OR THE LOWER 90S SATURDAY AND SUNDAY
DUE TO EXPECTED CLOUD COVER AND POSSIBLE PRECIPITATION.
TEMPERATURES MAY WARM BACK UP EARLY TO MID NEXT WEEK (UPPER 90S TO
NEAR 100F) AS UPPER LEVEL TROUGHING DEVELOPS OVER THE NORTHERN
ROCKIES OR ALONG THE WEST COAST, WITH RIDGING ACROSS THE CENTRAL
PLAINS. ALTHOUGH ISOLATED THUNDERSTORMS CANNOT BE RULED OUT,
PRECIPITATION CHANCES LOOK VERY LOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1201 PM CDT TUE JUL 16 2013
DDC 12Z SOUNDING, UPPER AIR ANALYSIS AND NAM BUFR SOUNDINGS
INDICATING A FAIRLY DEEP LAYER OF MOISTURE WILL BE PRESENT THROUGH
EARLY TONIGHT AT DDC AND GCK. AS A RESULT CLOUD BASES WILL
IMPROVE, HOWEVER MVFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH
AT LEAST 00Z WEDNESDAY. THE EXCEPTION WILL BE HAYS WERE BUFR
SOUNDINGS INDICATED VFR CONDITIONS WILL BE LIKELY THIS AFTERNOON
AND EARLY TONIGHT. THERE WILL ALSO BE A CHANCE FOR SHOWERS THIS
AFTERNOON AND EARLY TONIGHT, MAINLY IN THE GCK AND DDC AREA AS AN
UPPER LEVEL DISTURBANCE ROTATES AROUND AN UPPER LOW THAT WILL BE
LOCATED ACROSS EASTERN NEW MEXICO. SOUTHEAST WINDS AT AROUND 15KTS
WILL DECREASE TO 10KTS OR LESS AFTER SUNSET.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 62 87 65 92 / 20 10 10 0
GCK 60 87 64 92 / 20 10 0 0
EHA 59 84 64 90 / 30 10 10 10
LBL 62 85 64 91 / 20 10 10 0
HYS 63 91 67 94 / 10 10 10 0
P28 65 88 68 92 / 20 20 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...BURGERT
LONG TERM...FINCH
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
353 PM EDT TUE JUL 16 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 345 PM EDT TUE JUL 16 2013
UPPER AIR PATTERN CONSISTS OF A STRONG 500 MB RIDGE OVER THE LOWER
GREAT LAKES WITH A TROUGH OVER SOUTH CENTRAL CANADA WITH CLOSED LOWS
OFF THE CA COAST AND ONE OVER ERN NM. THE 500 MB RIDGE REMAINS
STATIONARY TODAY WITH THE TROUGH CONTINUING TO MOVE EAST ACROSS
CENTRAL CANADA. THIS TROUGH HELPS TO START PUSHING DOWN THE RIDGE
THIS FORECAST PERIOD WITH THE WESTERLIES ALONG THE CANADIAN/U.S.
BORDER MOVING SLOWLY SOUTH WITH A COLD FRONT MOVING SLOWLY SOUTH AS
WELL.
SPOTTY CONVECTION THAT HAS BEEN KICKED OFF THIS AFTERNOON WAS CAUSED
BY REACHING CONVECTIVE TEMPERATURE WHICH WAS IN THE UPPER 80S. 12Z
GRB SOUNDING HAD A CONVECTIVE TEMPERATURE OF 87 AND THIS SEEMS TO BE
WHAT TEMPERATURES HAVE TO GET TO TO KICK OFF CONVECTION. RUC IS ALSO
SHOWING A 500 MB SPEED MAX JUST TO THE NORTH OF THE AREA AND WITH
MOISTURE ADVECTION...THIS ALSO HELPED TO KICK OFF THE CONVECTION
THIS AFTERNOON. LOOK FOR THIS TO CONTINUE INTO THE EVENING BEFORE
INSTABILITY DIMINISHES WITH LOSS OF HEATING TO STOP THE
THUNDERSTORMS FROM CONTINUING TO DEVELOP. STUFF HAS BEEN FAIRLY
SHORT LIVED AND EXPECT THAT TREND TO CONTINUE THIS AFTERNOON INTO
THIS EVENING.
BUMPED UP SOME LOW TEMPERATURES TONIGHT WITH A SOUTHWEST WIND
ALLOWING DOWNSLOPE TO CONTINUE AND A FEW SW AFFECTED DOWNSLOPE AREAS
COULD HAVE LOWS IN THE MID 70S TONIGHT WHICH IS VERY WARM.
OTHERWISE...DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST FOR
TEMPERATURES FOR HIGHS ON WED. AGREE WITH SPC OUTLOOK FOR SLIGHT
RISK OF SEVERE THUNDERSTORMS TOMORROW WITH UNIDIRECTIONAL WINDS AND
POOLING OF MOISTURE NEAR THE FRONT TO ALLOW STORMS WITH HIGH WINDS
TO DEVELOP WHICH WOULD BE THE MAIN THREAT FOR SEVERE WEATHER. FRONT
STARTS TO SAG DOWN INTO THE AREA AS WELL SO A FOCUSING MECHANISM FOR
CONVECTION IS THERE.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 345 PM EDT TUE JUL 16 2013
WEDNESDAY NIGHT...THE VERY SLOW MOVING COLD FRONT STRETCHING FROM
NORTH DAKOTA EASTWARD INTO SOUTHWESTERN QUEBEC WILL BECOME
STATIONARY OVERNIGHT WEDNESDAY NIGHT. AT THE SAME TIME HEIGHT FALLS
ASSOCIATED WITH THE UPPER LEVEL 500MB LOW OVER JAMES BAY WILL BEGIN
TO SINK SLOWLY SOUTHWARD AS IT SLOWLY WEAKENS THE HIGH PRESSURE
RIDGE THAT REMAINS OVER MUCH OF THE SOUTHEASTERN U.S. WITH THE FRONT
STRETCHING ACROSS MUCH OF LAKE SUPERIOR INTO THE NORTHERN PORTIONS
OF THE U.P. EXPECT THAT FORCING WILL BE GREAT ENOUGH TO ENHANCE THE
CHANCES FOR SHOWERS AND THUNDERSTORMS ACROSS MUCH OF THE AREA.
CONVERGENCE ASSOCIATED WITH A 25 TO 30 KNOT 850MB LLJ OVER CENTRAL
MN INTO NORTHERN WI WILL KEEP SHOWERS AND THUNDERSTORMS IN THE
FORECAST THROUGH THE OVERNIGHT HOURS...EVEN WITH THE LOSS OF DAYTIME
HEATING. DURING THE OVERNIGHT HOURS...THE CWA WILL ALSO BE UNDER
THE INFLUENCE OF THE RIGHT ENTRANCE REGION OF AN UPPER LEVEL 300MB
JET MAX...HELPING TO INCREASE FORCING FOR ASCENT. MU CAPE VALUES
OVERNIGHT ARE STILL EXPECTED TO BE AROUND 1000-1500 J/KG WITH DEEP
LAYER SHEAR VALUES ON THE ORDER OF 30 TO 35 KNOTS ACROSS THE AREA.
THE SHEAR IS UNIDIRECTIONAL...WHICH WOULD ALSO FAVOR MORE OF A WIND
THREAT. IT WOULD DEFINITELY NOT BE OUT OF THE QUESTION FOR SOME OF
THE STORMS TO BE FAIRLY STRONG OR EVEN SEVERE. THE MAIN THREAT FROM
THESE STORMS WOULD BE STRONG GUSTY WINDS AS DRY AIR REMAINS IN THE
MID LEVELS ALONG WITH AN INVERTED V TYPE SOUNDING IN THE LOW LEVELS
THROUGH THE OVERNIGHT HOURS...HELPING TO INCREASE COLD POOL
DEVELOPMENT. IT SHOULD BE KEPT IN MIND THAT MUCH OF THIS DEPENDS ON
CONVECTIVE DEVELOPMENT/TRACK THROUGH THE DAYTIME HOURS WEDNESDAY.
THURSDAY THROUGH FRIDAY...THE STATIONARY FRONT POSITIONED OVER LAKE
SUPERIOR THURSDAY MORNING IS PROGGED BY THE GFS/EC/GEM TO BEGIN
LIFTING NORTHWARD AS A WARM FRONT DURING THE AFTERNOON HOURS
THURSDAY. THIS FRONT WILL CONTINUE TO LIFT NORTHWARD INTO ONTARIO
DURING THE EVENING HOURS AS A COLD FRONT IS PUSHED SOUTHEASTWARD OUT
OF SOUTHERN MANITOBA INTO NORTHEASTERN MN DURING THE OVERNIGHT
HOURS AS THE UPPER LEVEL TROUGH BEGINS TO DIG INTO THE REGION. WITH
THE FRONT LIFTING NORTHWARD DURING THE DAY THURSDAY...IT WOULD NOT
BE OUT OF THE QUESTION TO SEE THE CLOUDS BREAK UP OVER THE
AREA...WHICH WILL HELP TO INCREASE THE CHANCES FOR SEVERE WEATHER
ACROSS THE CWA AS INSTABILITY INCREASES TO AROUND 1500-2500 J/KG.
DEEP LAYER SHEAR VALUES THROUGH THE DAY THURSDAY ARE PROGGED TO BE
AROUND 35 TO 40 KNOTS WHICH WOULD BE FAVORABLE FOR SEVERE WEATHER
DEVELOPMENT. THURSDAY AND THURSDAY EVENING WIND PROFILES INDICATED
THAT BOTH SPEED AND DIRECTIONAL SHEAR ARE AVAILABLE WHICH WOULD
SUPPORT A MORE ORGANIZED SEVERE EVENT. WHILE THE SOUNDING GAINS A
BIT MORE MOISTURE THROUGHOUT...DRY AIR REMAINS IN PORTIONS OF THE
LOWER LEVELS ALLOWING FOR AN INCREASED SEVERE WIND THREAT THROUGH
THE DAY THURSDAY INTO THE EVENING HOURS. A GREAT DEAL OF THE SEVERE
THREAT DURING THE DAY THURSDAY IS DEPENDENT UPON CLOUD COVER.
OVERNIGHT THURSDAY THROUGH FRIDAY MORNING THE COLD FRONT TO THE
NORTHWEST OF THE AREA WILL CONTINUE SOUTHEASTWARD PUSHING SOUTHEAST
OF THE AREA BY LATE FRIDAY AFTERNOON. AHEAD OF THE COLD FRONT
SHOWERS AND THUNDERSTORMS WILL CONTINUE TO BE LIKELY. STRONG TO
SEVERE THUNDERSTORMS WILL BE POSSIBLE THROUGH EARLY FRIDAY MORNING
AS 0-6KM SHEAR VALUES ARE EXPECTED TO BE AROUND 40 TO 45 KNOTS ALONG
AND AHEAD OF THE FRONT...WITH SHEAR VECTORS BECOMING PERPENDICULAR
TO THE FORCING. THE SEVERE THREAT WILL SHIFT SOUTHEASTWARD INTO THE
LOWER GREAT LAKES BY FRIDAY AFTERNOON AS THE FRONT SHIFTS OUT OF THE
AREA. WITH THAT BEING SAID A FEW SHOWERS MAY LINGER INTO THE
AFTERNOON HOURS AS THE UPPER LEVEL 500MB THROUGH MOVES DIRECTLY
OVERHEAD.
FRIDAY NIGHT THROUGH SUNDAY NIGHT...FRIDAY NIGHT THE UPPER LEVEL
500MB TROUGH AXIS LINGERS OVER THE UPPER GREAT LAKES ALONG WITH
REMNANT MOISTURE. THIS WILL KEEP THE CHANCE OF ISOLATED SHOWERS IN
THE FORECAST THROUGH FRIDAY NIGHT. SATURDAY...HIGH PRESSURE BUILDING
OVER SOUTHERN CANADA INTO THE NORTHERN PLAINS WILL BEGIN BUILDING
EASTWARD INTO THE GREAT LAKES REGION. AS THIS HAPPENS FLOW AROUND
THE EASTERN SIDE OF THE HIGH WILL ALLOW DRY AIR FROM CANADA TO SPILL
SOUTHWARD HELPING TO CLEAR THE SKIES FOR THE WEEKEND AND DRY THINGS
OUT A BIT. THIS HIGH IS PROGGED TO REMAIN IN THE AREA THROUGH
SUNDAY NIGHT.
MONDAY THROUGH TUESDAY...DIFFERENCES REMAIN IN MODEL SOLUTIONS TO
THE WEATHER PATTERN FOR THE FIRST HALF OF NEXT WEEK. THE GFS KEEPS
ZONAL TO SLIGHTLY RIDGED FLOW AT 500MB ACROSS THE AREA THROUGH THIS
TIME PERIOD WHILE THE EC BRINGS AND UPPER LEVEL TROUGH INTO THE
REGION. AT THE SAME TIME THE GFS PLACES A SURFACE HIGH OVER THE AREA
WHILE THE EC BUILDS A SURFACE LOW INTO THE REGION OUT OF SOUTHERN
CANADA. WITH THIS CONTINUED DISCONTINUITY...WILL STICK WITH A
CONSENSUS OF THE MODELS DURING THIS TIME PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 110 PM EDT TUE JUL 16 2013
VFR CONDITIONS WILL CONTINUE THROUGH THE PERIOD AT ALL SITES. ISOLD
SHRA/TS WL THEN POP UP WITH AFTERNOON HEATING AND PSBLY IMPACT SAW
BEFORE THE ARRIVAL OF DRYING ALF TENDS TO DIMINISH THIS ACTIVITY
LATE IN THE AFTN AND HAVE VCSH TO COVER THIS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 345 PM EDT TUE JUL 16 2013
FOG WILL CONTINUE TO BE PATCHY THROUGH WED MORNING ON LAKE SUPERIOR
AS COLD WATER WITH WARM AND HUMID AIR MOVING OVER THE TOP CAUSES FOG
TO FORM. AS THE FRONT STARTS TO COME DOWN ON WED...THIS SHOULD
DISRUPT THE FOG. A LOW PRESSURE SYSTEM AND FRONTAL BOUNDARY WILL
EFFECT THE REGION WEDNESDAY THROUGH FRIDAY...HOWEVER...WINDS SHOULD
REMAIN LIGHT AND GENERALLY LESS THAN 15 KNOTS. HIGH PRESSURE BUILDS
IN FOR MUCH OF THE WEEKEND ALLOWING WINDS TO REMAIN LIGHT AND
VARIABLE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...07
LONG TERM...KEC
AVIATION...07
MARINE...07
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
111 PM EDT TUE JUL 16 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 419 AM EDT TUE JUL 16 2013
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW SPRAWLING UPR RDG
CENTERED OVER THE LOWER GRT LKS. ALTHOUGH THE 00Z GRB RAOB INDICATES
THE TROPOSPHERE OVER THE UPR GRT LKS HAS MOISTENED CONSIDERABLY OVER
THE LAST DAY OR SO WITH 00Z PWAT UP TO 1.82 INCHES /185 PERCENT OF
NORMAL/...MID LVL WARMTH WITH H5 TEMPS ARND -5C HAS MAINTAINED
RATHER UNIMPRESSIVE MID LVL LAPSE RATES IN THE ABSENCE OF ANY
DYNAMIC FORCING UNDER THE RDG. THE CONVECTIVE TEMP ON THE 00Z GRB
SDNG WAS 94. A FEW -SHRA DID POP UP OVER WI YDAY AFTN...BUT THESE
DISSIPATED LAST EVNG WITH THE LOSS OF DAYTIME HEATING. HOWEVER...
MORE ISOLD -SHRA HAVE DVLPD OVER NW WI/ADJOINING MN IN AREA WHERE
RUC ANALYSIS SHOWS KINX NEAR 36. PERSISTENT BAND OF MSTR THAT HAS
PLAGUED NE MN/NW LK SUP WITH CLDS/SOME SHRA THE LAST FEW DAYS HAS
DRIFTED TO THE N INTO ONTARIO. OTRW...SFC TEMPS ARE RUNNING WELL ABV
NORMAL EARLY THIS MRNG DESPITE CLR-PCLDY SKIES. TO THE NW...THERE IS
A STRONGER SHRTWV JUST W OF LK WINNIPEG MOVING ENEWD THRU SRN CANADA.
MAIN FCST CONCERNS IN THE SHORT TERM ARE TEMPS AND SHRA/TS CHCS AS
UPR RDG REMAINS DOMINANT OVER THE GRT LKS.
TODAY...CENTER OF UPR RDG/SFC HI PRES OVER THE LOWER GRT LKS IS FCST
TO DRIFT ONLY SLOWLY TO THE W...SO MID LVL WARM AIR WL REMAIN OVER
THE CWA. STRONGER SHRTWV/ACCOMPANYING DYNAMICS LIFTING ENEWD THRU
SCENTRL CANADA WL RIDE WELL TO THE N OF UPR MI AND NOT IMPACT THE
CWA. BUT WITH DAYTIME HEATING...BULK OF NUMERICAL MODELS GENERATE
SHRA/TS OVER UPR MI TODAY. THERE ARE A NUMBER OF NEGATIVES FOR
PCPN...THE ABSENCE OF ANY DYNAMIC FORCING...FCST ACYC H85 SW FLOW
THAT WL RESULT IN ONLY WEAK LK BREEZE DVLPMENT OFF LK SUP...AND VERY
HI CONVECTIVE TEMP SHOWN ON THE 00Z GRB RAOB. HOWEVER...WITH SOME
ISOLD -SHRA OVER NW WI...SUSPECT SOME SHRA/TS WL IMPACT UPR MI
MAINLY BY LATE MRNG AFTER ONSET OF DAYTIME HEATING. FCST DRYING IN
THE AFTN IN THE WAKE OF AREA OF HIER KINX NOW MOVING TOWARD THE CWA
MAY CAUSE THE SHRA TO DIMINISH DESPITE MOVING TOWARD PEAK HEATING
TIME. THE BEST CHC FOR MORE PERSISTENT SHRA/TS WL BE OVER THE
ECENTRL CWA ON THE EDGE OF THE LK BREEZE BNDRY MOVING ONSHORE FM LK
MI. WITH FCST H85 TEMPS ARND 19C...EXPECT ANOTHER WARM DAY WITH MAX
TEMPS WELL INTO THE 80S TO LO 90S OVER THE INTERIOR. HIER HUMIDITY
WL MAKE THE AIR FEEL QUITE UNCOMFORTABLE...WITH APPARENT TEMPS
RISING TO ARND 95 AT SOME PLACES.
TNGT...COLD FNT ATTENDANT TO DISTURBANCE MOVING THRU CANADA AND INTO
HUDSON BAY IS PROGGED TO DRIFT S INTO NRN LK SUP BY 12Z WED UNDER
MODEST H5 HGT FALLS. CURRENT FCST SHOWS OVERNGT POPS OVER NRN LK SUP
CLOSE TO THIS INCOMING BNDRY AND AREA OF HIER FCST MID LVL RH...SO
WL RESTRICT FCST POPS TO THIS AREA AND KEEP THE REST OF THE CWA DRY
CLOSER TO HI PRES/CORE OF WARMER MID LVL AIR. WITH FCST H925 WINDS
UP TO 25-30 KTS UNDER SHARPENING PRES GRADIENT TO THE S OF THIS
INCOMING FNT...OVERNGT LO TEMPS SHOULD BE FAIRLY WARM...ESPECIALLY
IN THE DOWNSLOPE AREAS NEAR LK SUP.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 419 AM EDT TUE JUL 16 2013
STARTING OUT THE LONG TERM AT 12Z WED...THE CWA WILL BE BETWEEN AN
UPPER HIGH CENTERED OVER IN AND A LOW PRESSURE SYSTEM OVER NRN
HUDSON BAY. STRETCHING FROM THE HUDSON BAY LOW WILL BE A
TROUGH/FRONT OVER QUEBEC SW TO THE NRN CWA. THE FRONT WILL NOT MOVE
MUCH THROUGH THU...WITH SLOW SOUTHERLY MOVEMENT OR NEARLY STATIONARY
BEHAVIOR EXPECTED. WIND FIELDS WILL BE NEAR UNIDIRECTIONAL AND FOR
THE MOST PART PARALLEL TO THE FRONT. WITH INSTABILITY ALONG AND S OF
THE FRONT...EXPECT CONVECTION FOR MUCH OF THE PERIOD. TROUBLE COMES
WITH POSSIBILITIES OF STRONG TO SEVERE STORMS AND FLOODING. WINDS
PARALLEL TO THE SLOW MOVING FRONT AND PWATS OF 1.5-2.0 INCHES
/150-200 PERCENT OF NORMAL/ COMBINED WITH INSTABILITY MAY MAKE FOR
SOME AREAS RECEIVING EXCESSIVE RAINFALL...BUT IT IS TOO DIFFICULT AT
THIS TIME FRAME TO TELL WHERE EXACTLY THAT WILL BE /MORE OF A
NOWCASTING ISSUE/. AS FOR STRONG-SEVERE POTENTIAL WED-THU...THE BEST
CHANCE FOR GOOD INSTABILITY LOOKS TO BE ON WED AS THE FRONT WILL BE
MOVING INTO UPPER MI...WHILE THU LOOKS MORE UNCERTAIN SINCE THE
POSITION OF THE FRONT AND CLOUD COVER ARE MORE IN QUESTION.
FOR THE SPECIFICS FOR WED...CAPE VALUES OF 1500-2500J/KG ARE
POSSIBLE AS SFC TEMPS WARM INTO THE 80S TO AROUND 90. 0-6KM BULK
SHEAR LOOKS TO BE AROUND 30KTS /AS PREVIOUSLY STATED...THAT IS
MOSTLY UNIDIRECTIONAL/. DCAPE VALUES LOOK TO BE AOB 1000J/KG THANKS
TO SOME DRY LAYERS IN THE SOUNDING...WHICH MAY HELP GET SOME STRONG
WINDS OUT OF STORMS. MAY SEE THUNDERSTORMS INITIATE IN THE
AFTERNOON...OR COULD EVEN SEE A CONVECTIVE COMPLEX MOVE ALONG THE
FRONT. WITH WEAK SFC WINDS...MAY SEE CONVECTION FOCUSING ON LAKE
FREEZES THAT FORM. CONVECTION MAY THEN CONTINUE INTO WED NIGHT...BUT
WOULD MORE LIKELY BE ELEVATED WITH STRONG/SEVERE POTENTIAL
CONTINUING DUE TO AN INCREASE IN THE NOCTURNAL LOW LEVEL JET...BUT
IT WOULD LIKELY DEPEND MORE ON THE PATH OF ANY CONVECTIVE COMPLEXES
THAT MAY FORM.
THU...AS SAID BEFORE...MORE UNCERTAINTY WITH CONVECTIVE CHANCES DUE
TO QUESTIONS ABOUT FRONTAL LOCATION AND CLOUD COVER. SHOULD BE LESS
DCAPE AS MORE MOISTURE WILL HAVE MOVED INTO THE AREA...SO OVERALL
THINK THE CHANCE OF STRONGER/SEVERE STORMS IS MORE LIMITED THAN WED.
SHOULD SEE CONVECTION CONTINUE INTO THU NIGHT AS HEIGHT FALLS MOVE
INTO THE REGION AS THE UPPER LOW DROPS TO SRN HUDSON BAY...WHICH
WILL BOOST FORCING ACROSS THE CWA WHILE THE FRONT REMAINS FAIRLY
STATIONARY. THREAT OF HEAVY RAIN/TRAINING STORMS CONTINUES...BUT THE
LOCATION IS AGAIN NEARLY IMPOSSIBLE TO PINPOINT AT THIS TIME. SFC
TEMPS SHOULD BE COOLER IN THE 70S TO MID 80S.
FRI-SAT...THE UPPER LOW WILL WEAKEN WHILE MOVING TO JAMES BAY BY 12Z
SAT...THEN TO NRN QUEBEC BY 00Z SUN. THIS WILL ALLOW A MORE
SIGNIFICANT UPPER TROUGH TO SWING ACROSS THE CWA FRI INTO
SAT...WHICH WILL PUSH THE COLD FRONT WELL S OF THE CWA BY FRI NIGHT.
MAY STILL SEE SOME SHOWERS ON FRI AFTERNOON AS THE TROUGH PUSHES
IN...BUT TEMPS WILL BE COOLER WITH HIGHS IN THE 70S TO LOW 80S IN
MOST LOCATIONS. ALTHOUGH THE UPPER TROUGH IS STILL MOVE THROUGH
SAT...SFC HIGH PRESSURE AND ASSOCIATED DRY AIR OVER THE CWA SHOULD
KEEP THINGS DRY FOR THE MOST PART. HIGHS SAT LOOK TO BE IN THE 60S
AND 70S.
THERE IS THE POSSIBILITY OF ANOTHER TROUGH MOVING THROUGH ON SUN AND
MON /BEST CHANCES ON MON/...WHICH WOULD LEAD TO PRECIP ACROSS MUCH
OF THE CWA. HOWEVER...CONFIDENCE ON THE POSITION/TIMING/EXTENT OF
THE TROUGH IS LOW AT THIS POINT...SO WILL JUST CONTINUE TO LOAD A
CONSENSUS OF MODELS INTO FORECAST FOR THIS TIME PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 110 PM EDT TUE JUL 16 2013
VFR CONDITIONS WILL CONTINUE THROUGH THE PERIOD AT ALL SITES. ISOLD
SHRA/TS WL THEN POP UP WITH AFTERNOON HEATING AND PSBLY IMPACT SAW
BEFORE THE ARRIVAL OF DRYING ALF TENDS TO DIMINISH THIS ACTIVITY
LATE IN THE AFTN AND HAVE VCSH TO COVER THIS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 419 AM EDT TUE JUL 16 2013
WITH WEAK PRES GRADIENT AND HI STABILITY OVER THE RELATIVELY CHILLY
LAKE WATERS...EXPECT LIGHT WINDS UNDER 20 KTS THRU TONIGHT. THE
PERSISTENCE OF A FAIRLY HUMID AIRMASS OVER THE LAKE WILL RESULT IN
PATCHY FOG. A LOW PRESSURE SYSTEM AND FRONTAL BOUNDARY WILL EFFECT
THE REGION WEDNESDAY THROUGH FRIDAY...HOWEVER...WINDS SHOULD REMAIN
LIGHT AND GENERALLY LESS THAN 15 KNOTS. HIGH PRESSURE BUILDS IN FOR
MUCH OF THE WEEKEND ALLOWING WINDS TO REMAIN LIGHT AND VARIABLE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...07
MARINE...KC/TITUS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
323 PM MDT TUE JUL 16 2013
.SHORT TERM...VALID FOR WED AND THU...
STUBBORN POST FRONTAL STRATUS DEVELOPED OVER MUCH OF THE FORECAST
AREA TODAY AIDED BY A DEEP UPSLOPE FLOW...AND BY THE TIME IT
BEGAN THINNING OUT MID LEVEL CLOUDS WERE INVADING THE REGION.
THUS...MOSTLY CLOUDY SKIES LIMITED INSOLATION AND LED TO A BUSTED
FORECAST AT MANY LOCATIONS WITH REGARDS TO SKY AND TEMPERATURES.
SHOWERS WERE SPREADING ACROSS OUR WESTERN MOUNTAINS IN A PUSH OF
MONSOONAL TYPE MOISTURE. ALSO...SOME ELEVATED WEAK THUNDERSTORMS
HAVE DEVELOPED IN ROSEBUD COUNTY. THIS LOOKS RELATED TO A THERMAL
TROUGH AT 500MB. I WILL MENTION LOW POPS IN THE EAST THIS EVENING
AS THIS THERMAL TROUGH FEATURE TRACKS ACROSS...AND EXTEND THE POPS
A BIT SOUTH BASED ON MID LEVEL LAPSE RATES ACROSS THE EASTERN
PLAINS. I ALSO PUSHED POPS IN THE WEST FURTHER EAST FOR THIS
EVENING BASED ON CURRENT SATELLITE AND RADAR IMAGERY. HRRR SEEMS
TO BE PICKING UP THESE TRENDS BEST AND USED IT AS A PROXY FOR
PLACEMENT OF POPS.
FOR WEDNESDAY...THIS SHOULD BE OUR BEST CHANCE OF WIDESPREAD AND
HEAVY PRECIPITATION FOR THE REST OF THE WEEK. A BETTER PUSH OF
MONSOONAL FLOW WILL INVADE FROM THE SOUTH OVER OUR MOUNTAIN
LOCATIONS AND ROTATE A BIT NORTHEAST. HIGH CHANCE TO LOW LIKELY
POPS SEEM GOOD FOR NOW. ONCE WE IDENTIFY A BATCH OF MOISTURE IN
THE SOUTHERLY FLOW WE WILL BE ABLE TO INCREASE POPS AS
APPROPRIATE. DESPITE CLOUD COVER TOMORROW...TEMPERATURES SHOULD BE
BACK AROUND NORMAL AS 850-700 MB TEMPS INCREASE UNDER THE RIDGE.
THURSDAY...OUR RIDGE WILL BE SUPPRESSED AS A LARGE UPPER LOW
TRACKS OVER THE HUDSON BAY REGION. LOOK FOR A FEW THUNDERSTORMS TO
LINGER OVERNIGHT WEDNESDAY INTO THURSDAY AS THEY GRADUALLY MAKE
THEIR WAY EASTWARD. HOWEVER...THE MOISTURE TO THE SOUTH WILL BE
BECOME LARGELY CUT OFF FOR THE TIME BEING. I WILL KEEP THE
HIGHEST POPS IN THE SOUTH AND EAST. TEMPERATURES WILL REMAIN
AROUND NORMAL. BT
.LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE...
LITTLE IN THE WAY OF CHANGES THROUGH THE EXTENDED PERIOD...WITH
MODELS CONTINUING TO BE IN GOOD AGREEMENT. MAINLY DRY AND HOT
CONDITIONS WILL PREVAIL THROUGH THE EXTENDED PERIOD.
THE EXTENDED FORECAST PERIOD BEGINS FRIDAY AND APPEARS TOP BE THE
COOLEST DAY...WITH BEST POTENTIAL FO PRECIP. AS RIDGE BUILDS JUST
TO THE WEST...MODELS ARE HINTING AT A BACKDOOR COLD FRONT
SLIPPING IN FROM THE NORTHEAST. THE DIFFICULTY IS GAUGING JUST
HOW FAR INTO THE AREA THIS COOL AIR WILL PUSH...IF AT ALL.
CURRENTLY THIS APPEARS TO BE VERY LITTLE WITH ANY IMPACTS PUSHED OFF
TO THE EAST AND NORTHEAST..BUT WILL BARE ATTENTION IN LATER
SHIFTS. MEANWHILE MONSOONAL FLOW WILL CONTINUE FROM THE
SOUTHWEST...BUT IS GREATLY SUPPRESSED BY DEVELOPING RIDGE. SO BEST
CHANCES FOR PRECIP WILL BE IN EXTREME SOUTHERN ZONES...PRIMARILY
HIGH TERRAIN...WITH A VERY SLIGHT CHANCE AROUND KBHK.
FLAT RIDGING BEGINS TO PUSH EASTWARD OVERNIGHT FRIDAY AND
DOMINATES THE PATTERN THROUGH THE REMAINDER OF THE FORECAST
PERIOD. MONSOONAL FLOW WILL SUPPRESSED BY THE RIDGE AND PUSHED OFF
TO THE EAST OF THE AREA. THIS WILL RESULT IN INCREASINGLY DRY AND
HOT CONDITIONS THROUGH THR REMAINDER OF THE FORECAST PERIOD.
TEMPERATURES WILL BE AROUND SEASONAL FOR FRIDAY AND SATURDAY...AND
CLIMB TO MID 90S THROUGH THE REMAINDER OF THE PERIOD...WITH SOME
POTENTIAL FOR REACHING THE CENTURY MARK IN SOME AREAS IF STRONGER
DOWNSLOPE FLOW PANS OUT. AAG
&&
.AVIATION...
STRATUS DECK PERSISTS ACROSS MUCH OF THE CWA...WITH SHOWERS AND
THUNDERSTORMS DEVELOPING...ESPECIALLY IN THOSE AREAS THAT RECEIVED
BETTER HEATING TODAY IN EXTREME NORTHERN ROUTES...AND ALONG THE
HIGH TERRAIN. WIDESPREAD MVFR PERSISTS UNDER LOW STRATUS
CIGS...WITH LOCALIZED IFR VIS POTENTIAL IN HEAVIER PRECIP. 10-20
KNOT NORTHEAST TO EAST WINDS ARE COMMON ACROSS THE REGION TODAY...
WITH GUSTS AS HIGH AS 30 KNOTS POSSIBLE AT KLVM. AAG
&&
.PRELIMINARY POINT TEMP/POPS...
WED THU FRI SAT SUN MON TUE
-----------------------------------------------------------
BIL 062/090 065/092 061/089 064/092 065/096 065/096 064/095
32/T 32/T 21/B 10/B 00/U 01/U 11/U
LVM 059/090 058/091 053/091 052/095 052/097 052/094 054/094
35/T 42/T 21/B 10/B 00/U 01/U 11/B
HDN 062/093 065/093 060/091 059/094 061/098 061/097 060/096
22/T 22/T 21/B 11/B 10/U 01/U 11/U
MLS 063/094 068/094 063/090 065/093 066/096 066/097 064/094
22/T 22/T 11/B 11/B 11/U 11/U 11/U
4BQ 060/094 062/092 059/088 060/091 060/094 061/096 060/092
11/B 12/T 11/B 11/B 11/U 11/U 11/U
BHK 058/091 063/090 059/086 061/089 061/092 062/094 061/091
11/B 12/T 21/U 11/U 12/T 21/U 11/U
SHR 058/091 060/092 057/089 057/091 057/095 057/095 057/095
12/T 22/T 32/T 21/B 10/U 01/U 11/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...CORRECTED
NWS BINGHAMTON NY
301 PM EDT TUE JUL 16 2013
.SYNOPSIS...
A LARGE AREA OF HIGH PRESSURE OVER THE OHIO VALLEY WITH VERY WARM
AND HUMID AIR WILL INFLUENCE OUR WEATHER THROUGH FRIDAY. A COLD
FRONT WILL DROP SOUTH OF THE REGION SATURDAY WITH A CHANCE FOR
STRONG THUNDERSTORMS. AFTER THIS FRONT PASSES BY...COOLER AND LESS
HUMID AIR WILL COVER THE REGION FOR EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
SCT CUMULUS IN CLOUD STREETS COVER MUCH OF THE CWA AS THE LL FLOW
IS NWRLY. DEWPOINTS WERE A BIT LOWER THIS AFTERNOON THAN YSTA
RUNNING IN THE MID TO UPPER 60S. RAP MODEL SOUNDINGS SHOW A
CAPPING INVERSION NR 800 MB WHICH WAS KEEPING DEEP CONVECTION IN
CHECK HENCE DON/T EXPECT ANY SHRA OR TSRA FOR THE REST OF TODAY OR
THIS EVENING.
FOR OVERNIGHT...EXPECT MORE VALLEY FOG SIMILAR TO THIS MORNING IN
OUR RIVER VALLEYS.
FOR WEDNESDAY...W-NW LL FLOW WILL ADVECT SLIGHTLY HIGHER DEWPOINTS
INTO C NY AND NE PA AS PER MODEL GUIDC. NAM AND GFS BOTH SHOW
HIGHER DEWPOINTS AT 850 MB COMING SOUTHEASTWARD BY WED WHICH SHUD
MIX DOWN WITH BNDRY LAYER GROWTH FROM INSOLATION. MODEL GUIDC
SUGGESTS DEWPOINTS IN THE LOWER 70S ALONG THE LAKE ONTARIO PLAIN
AND UPPER 60S REST OF CWA. HIGH TEMPERATURES ALREADY SHUD BE IN
THE LOW 90S TODAY IN SYR AND WUD EXPECT THE SAME FOR WED. HENCE
HEAT INDICES WED PM WILL BE CLOSE TO 100F IN THE SYR-AUBURN AREAS
WHICH IS OUR HEAT ADVY CRITERIA. SO ISSUED HEAT ADVY FOR A FEW
COUNTIES ALONG THE LAKE ONTARIO PLAIN INCLUDING SYR TO COVER.
ANOTHER CONCERN FOR WED WILL BE MORE INSTABILITY WITH A BIT HIGHER
DEWPOINTS. MODEL SOUNDINGS ALL SHOW CAPES BETWEEN 1500 J/KG AND
2000 J/KG BY WED PM. FORCING WILL BE WEAK BUT WITH A LL NW FLO
SEE SOME ISLD SHRA/TSRA FORMING FROM MTN VALLY CRLCNS AND LAKE
BOUNDARIES. SO WENT WITH SLGHT CHC TSRA IN MUCH OF CNTRL NY.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
FOR THURSDAY...SHORT WAVE TRACKING ACROSS SWRN AND SC CANADA WILL
REACH SERN CANADA BY THURSDAY PM...THIS WILL TURN THE MID TO UPPER
LVL FLOW MORE NWRLY AND PRESS A FRNT DOWN TO NRN NEW ENGLAND AND THE
UPPER LAKES. AT 500 MB THE TEMPERATURES BEGIN TO FALL FROM WEAK
CAA AS WELL FROM THE NW FLOW. AT LL/S THE DEWPOINTS AGAIN WILL BE
WITHIN A FEW DEGREES OF 70F. SO THINK THERE WILL BE SCT TSRA IN
NC NY TO ISLD CONVECTION FARTHER S TO NE PA AS CAPES ARE RUNNING
BETWEEN 1000 AND 1500 J/KG AND LL FLOW AGAIN RUNS UP INTO THE
HILLS OF NY AND NRN PA.
FOR FRIDAY...LONGER WAVELENGTH UPPER LEVEL FEATURE OVER SC CANADA
TO THE UPR MIDWEST WILL TURN THE LL FLOW MORE SWRLY AND ADVECT
SOMEWHAT HIGHER LL MOISTURE INTO NY AND PA AND INCREASE
INSTABILITY. CAPES CUD EXCEED 2000 J/KG. 0-6 KM BULK SHEAR WILL
ALSO BE BETWEEN 30 AND 40 KNOTS BY AFTERNOON. POTENTIAL IS FOR
SOME CONVECTION WELL IN ADVANCE OF THE FRONT. THE REGION WILL FALL
UNDER THE RIGHT ENTRANCE REGION OF A STRG UPPER LEVEL JET IN SERN
CANADA BY FRI PM TO ENHANCE UPPER DVRG. AT LL/S THERE IS A 30-35
KNOT W-SW LLJ RUNNING FROM THE LOWER LAKES TO NRN NY STATE. THIS
IS FAVORABLE TO SUPPORT STRG TO SVR CONVECTION ACRS NC NY WHERE
POPS WILL BE HIGHEST. WILL TAPER DOWN POPS SOME INTO NE PA FRI.
BOTH THURSDAY AND FRIDAY...HEAT INDICES WILL BE CLOSE TO 100F IN
NE PA AND SRN SULLIVAN CO NY AND POSSIBLY SC NY. THE LAKE ONTARIO
PLAIN LIKELY WILL REMAIN CLOSE TO 100F HEAT INDICES BOTH DAYS. FOR
NOW WILL COVER IN HWO...BUT MAY HAVE TO EXTEND HEAT ADVISORIES UP
THERE AND EXPAND HEAT ADVISORIES FARTHER S AND E.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
LTL CHG TO THE MED RNG FCST WHICH FEATURES THE PSSG OF A CANADIAN
CDFNT ON SAT...FOLLOWED BY MUCH MORE COMFORTABLE CONDITIONS. BEST
CHCS FOR TSRA APPEAR TO BE OVER NRN SXNS ON FRI NGT...SPREADING
INTO CNTRL NY AND NE PA ON SAT. POTNL FOR STRONG/SVR TSRA ON SAT GIVEN
THE MDL FCST WIND FIELDS AND INSTABILITY...WITH TIMING OF FNT
LOOKING QUITE FVRBL FOR SRN/CNTRL NY AND NE PA ON SAT. XPCT
LINGERING ACTIVITY TO PUSH OFF TO THE SE ON SAT NGT...WITH FAIR WX
AND MORE SEASONABLE TEMPS RETURNING ON SUNDAY. EARLY NXT WEEK
LOOKING FABULOUS WITH MAXES 75-80 AND LOWS INTO THE 50S...AND MUCH
LOWER HUMIDITY.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
HI PRES SFC AND ALOFT WITH VFR PREVAILING THRU 18Z WED. XPCT SCT
4-5 KFT CU DURING DAY...AND MAINLY SKC TNGT. ONLY EXCEPTION TO VFR
WILL BE VLY FOG/STRATUS LATE TNGT AFFECTING ELM IN THE 07-13Z
TIME FRAME. WINDS THIS AFTN NW TO NRLY 10 KTS...L&V TNGT...THEN
WRLY ON WED 10 KTS.
.OUTLOOK...
WED NGT/THU/FRI...VFR PREVAILS. CHANCE FOR LATE NGT/EARLY MRNG MVFR/IFR
FG/BR/HZ AT KELM. ISOLD OR WDLY SCT AFTN TSRA MAY ALSO PRODUCE
BRIEF RESTRICTIONS.
FRI NGT INTO SAT...MVFR IN TSRA...MOST NUMEROUS OVER NRN SITES FRI
NGT...AND AREA WIDE ON SAT.
SAT NGT...MVFR PSBL AT AVP IN SHRA/TSRA EARLY....IMPRVG TO VFR CNTRL
NY.
SUN...VFR.
&&
.CLIMATE...
BELOW ARE THE RECORD HIGHS FOR THE NEXT FEW DAYS AT OUR MAIN AIRPORTS
AND OUR FORECAST HIGHS. HIGH TEMPERATURES SHOULD FALL SHORT OF THE DAILY
RECORDS...
SYRACUSE HANCOCK FIELD...
TODAY 97 SET IN 1988. FORECAST 92
WEDNESDAY 101 SET IN 2012. FORECAST 92
THURSDAY 97 SET IN 1953. FORECAST 91
GREATER BINGHAMTON AIRPORT...
TODAY 98 SET IN 1988. TODAY`S FORECAST 88
WEDNESDAY 91 SET IN 1991. FORECAST 88
THURSDAY 93 SET IN 1953. FORECAST 88
SCRANTON/WILKES-BARRE INTERNATIONAL AIRPORT...
TODAY 101 SET IN 1988. TODAY`S FORECAST 91
WEDNESDAY 96 SET IN 1999. FORECAST 93
THURSDAY 98 SET IN 1953. FORECAST 93
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...HEAT ADVISORY FROM NOON TO 8 PM EDT WEDNESDAY FOR NYZ016>018.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...
AVIATION...
CLIMATE...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
213 PM EDT TUE JUL 16 2013
.SYNOPSIS...
A LARGE AREA OF HIGH PRESSURE OVER THE OHIO VALLEY WITH VERY WARM
AND HUMID AIR WILL INFLUENCE OUR WEATHER THROUGH FRIDAY. A COLD
FRONT WILL DROP SOUTH OF THE REGION SATURDAY WITH A CHANCE FOR
STRONG THUNDERSTORMS. AFTER THIS FRONT PASSES BY...COOLER AND LESS
HUMID AIR WILL COVER THE REGION FOR EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
SCT CUMULUS IN CLOUD STREETS COVER MUCH OF THE CWA AS THE LL FLOW
IS NWRLY. DEWPOINTS WERE A BIT LOWER THIS AFTERNOON THAN YSTA
RUNNING IN THE MID TO UPPER 60S. RAP MODEL SOUNDINGS SHOW A
CAPPING INVERSION NR 800 MB WHICH WAS KEEPING DEEP CONVECTION IN
CHECK HENCE DON/T EXPECT ANY SHRA OR TSRA FOR THE REST OF TODAY OR
THIS EVENING.
FOR OVERNIGHT...EXPECT MORE VALLEY FOG SIMILAR TO THIS MORNING IN
OUR RIVER VALLEYS.
FOR WEDNESDAY...W-NW LL FLOW WILL ADVECT SLIGHTLY HIGHER DEWPOINTS
INTO C NY AND NE PA AS PER MODEL GUIDC. NAM AND GFS BOTH SHOW
HIGHER DEWPOINTS AT 850 MB COMING SOUTHEASTWARD BY WED WHICH SHUD
MIX DOWN WITH BNDRY LAYER GROWTH FROM INSOLATION. MODEL GUIDC
SUGGESTS DEWPOINTS IN THE LOWER 70S ALONG THE LAKE ONTARIO PLAIN
AND UPPER 60S REST OF CWA. HIGH TEMPERATURES ALREADY SHUD BE IN
THE LOW 90S TODAY IN SYR AND WUD EXPECT THE SAME FOR WED. HENCE
HEAT INDICES WED PM WILL BE CLOSE TO 100F IN THE SYR-AUBURN AREAS
WHICH IS OUR HEAT ADVY CRITERIA. SO ISSUED HEAT ADVY FOR A FEW
COUNTIES ALONG THE LAKE ONTARIO PLAIN INCLUDING SYR TO COVER.
ANOTHER CONCERN FOR WED WILL BE MORE INSTABILITY WITH A BIT HIGHER
DEWPOINTS. MODEL SOUNDINGS ALL SHOW CAPES BETWEEN 1500 J/KG AND
2000 J/KG BY WED PM. FORCING WILL BE WEAK BUT WITH A LL NW FLO
SEE SOME ISLD SHRA/TSRA FORMING FROM MTN VALLY CRLCNS AND LAKE
BOUNDARIES. SO WENT WITH SLGHT CHC TSRA IN MUCH OF CNTRL NY.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
4 AM UPDATE...
CONTINUED HOT PERIOD WILL FEATURE GRADUAL FLATTENING OF LARGE
UPPER HIGH...AS WESTERLIES START TO CREEP ACROSS THE INTERNATIONAL
BORDER. MAIN CONCERN WILL BE FOR HIGH HEAT INDICES ECLIPSING HEAT
ADVISORY CRITERIA /100 DEGREES/ AT LOWER ELEVATIONS
WEDNESDAY...AND PERHAPS AGAIN THURSDAY AT LEAST IN THE SOUTHERN
ZONES. THIS WILL BE A RESULT OF DEWPOINTS EDGING BACK INTO THE
UPPER 60S/LOW 70S WHILE AS HIGHS STILL MANAGE UPPER 80S TO MID
90S. HEAT ADVISORIES WILL LIKELY BE NEEDED FOR AT LEAST LAKE PLAIN
AND WYOMING/DELAWARE VALLEYS IF NOT EVEN A BIGGER CHUNK OF THE
CWA WEDNESDAY...AND PERHAPS AGAIN FOR AT LEAST WYOMING/DELAWARE
VALLEYS THURSDAY. AS MENTIONED IN NEAR TERM DISCUSSION
THOUGH...REGARDLESS OF WHETHER OR NOT TECHNICALLY MEETING
CRITERIA...HEAT-RELATED PRECAUTIONS SHOULD BE EXERCISED.
AS FAR AS CONVECTION GOES...WITH FLATTENING OF THE RIDGE AND THUS
LOWERING OF 500MB HEIGHTS...CAP WILL BE WEAKENED AND THUS THE
CHANCE OF THUNDERSTORMS WILL FINALLY BE REINTRODUCED TO THE
FORECAST. ONLY OUTER PERIPHERY OF WESTERLIES AND TRAILING EDGES OF
EMBEDDED WAVES WILL BE SKIMMING INTO THE AREA...SO ONLY SLIGHT
CHANCE OF THUNDERSTORMS FIGURED FOR NORTHERN ZONES
WEDNESDAY...THEN AT LEAST LOW CHANCE RANGE ACROSS MOST THE AREA
THURSDAY /HIGHEST AGAIN NORTH/. THE BETTER...AND STRONGER...CONVECTION
THREATS WILL BE TOWARDS THE WEEKEND AS DISCUSSED IN THE LONG TERM
PORTION.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
LTL CHG TO THE MED RNG FCST WHICH FEATURES THE PSSG OF A CANADIAN
CDFNT ON SAT...FOLLOWED BY MUCH MORE COMFORTABLE CONDITIONS. BEST
CHCS FOR TSRA APPEAR TO BE OVER NRN SXNS ON FRI NGT...SPREADING
INTO CNTRL NY AND NE PA ON SAT. POTNL FOR STRONG/SVR TSRA ON SAT GIVEN
THE MDL FCST WIND FIELDS AND INSTABILITY...WITH TIMING OF FNT
LOOKING QUITE FVRBL FOR SRN/CNTRL NY AND NE PA ON SAT. XPCT
LINGERING ACTIVITY TO PUSH OFF TO THE SE ON SAT NGT...WITH FAIR WX
AND MORE SEASONABLE TEMPS RETURNING ON SUNDAY. EARLY NXT WEEK
LOOKING FABULOUS WITH MAXES 75-80 AND LOWS INTO THE 50S...AND MUCH
LOWER HUMIDITY.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
HI PRES SFC AND ALOFT WITH VFR PREVAILING THRU 18Z WED. XPCT SCT
4-5 KFT CU DURING DAY...AND MAINLY SKC TNGT. ONLY EXCEPTION TO VFR
WILL BE VLY FOG/STRATUS LATE TNGT AFFECTING ELM IN THE 07-13Z
TIME FRAME. WINDS THIS AFTN NW TO NRLY 10 KTS...L&V TNGT...THEN
WRLY ON WED 10 KTS.
.OUTLOOK...
WED NGT/THU/FRI...VFR PREVAILS. CHANCE FOR LATE NGT/EARLY MRNG MVFR/IFR
FG/BR/HZ AT KELM. ISOLD OR WDLY SCT AFTN TSRA MAY ALSO PRODUCE
BRIEF RESTRICTIONS.
FRI NGT INTO SAT...MVFR IN TSRA...MOST NUMEROUS OVER NRN SITES FRI
NGT...AND AREA WIDE ON SAT.
SAT NGT...MVFR PSBL AT AVP IN SHRA/TSRA EARLY....IMPRVG TO VFR CNTRL
NY.
SUN...VFR.
&&
.CLIMATE...
BELOW ARE THE RECORD HIGHS FOR THE NEXT FEW DAYS AT OUR MAIN AIRPORTS
AND OUR FORECAST HIGHS. HIGH TEMPERATURES SHOULD FALL SHORT OF THE DAILY
RECORDS...
SYRACUSE HANCOCK FIELD...
TODAY 97 SET IN 1988. FORECAST 92
WEDNESDAY 94 SET IN 1999. FORECAST 92
THURSDAY 97 SET IN 1953. FORECAST 91
GREATER BINGHAMTON AIRPORT...
TODAY 98 SET IN 1988. TODAY`S FORECAST 88
WEDNESDAY 91 SET IN 1991. FORECAST 88
THURSDAY 93 SET IN 1953. FORECAST 89
SCRANTON/WILKES-BARRE INTERNATIONAL AIRPORT...
TODAY 101 SET IN 1988. TODAY`S FORECAST 92
WEDNESDAY 96 SET IN 1999. FORECAST 94
THURSDAY 98 SET IN 1953. FORECAST 93
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...HEAT ADVISORY FROM NOON TO 8 PM EDT WEDNESDAY FOR NYZ016>018.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...MDP
LONG TERM...
AVIATION...
CLIMATE...DJN
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
254 PM MDT TUE JUL 16 2013
.SHORT TERM...THIS EVENING THROUGH WEDNESDAY NIGHT
ISSUED AT 253 PM MDT TUE JUL 16 2013
AT 20Z A MODERATE AMOUNT OF CU DEVELOPMENT WAS TAKING
PLACE ALONG THE COOL FRONT BOUNDAY ACROSS EXTREME NORTHWESTERN SOUTH
DAKOTA THIS AFTERNOON. NO LIGHTNING YET, BUT THE HRRR 17Z UPDATE
SHOWED SOME MINIMAL RW- ACTIVITY BETWEEN 00Z AND 02Z JUST BARELY
ACROSS THE NORTHWEST CORNER OF THE STATE. THE SOUTHEASTERN EDGE OF
THE SOUTHEASTERN MONTANA LOW ST FIELD MENTIONED IN THE MORNING
UPDATE WAS DISSIPATING AND RETREATING NORTHWARD AS THE CYCLONIC
CIRCULATION AROUND THE WEAK SURFACE LOW BECAME MORE EASTERLY IN THIS
REGION.
ON A LARGER SCALE THE RIDGE EXTENDING WESTWARD INTO THE CENTRAL
PLAINS HAS PRETTY MUCH CUT OFF SIGNIFICANT MOIST RETURN FLOW TO THE
DAKOTAS THIS AFTERNOON IN THE MID AND UPPER LEVELS . DEWPOINTS ARE
DOWN 10 TO 12 DEGREES FROM YESTERDAY AFTERNOON AND MODEL SOUNDINGS
SHOW A VERY DRY STABLE AIR MASS.
FOR WEDNESDAY THE WEAK COOL FRONT IS FORECAST TO DRIFT SOUTHWARD
ACROSS NORTHWEST SOUTH DAKOTA. HOWEVER THE WESTERLYS AND ANY UPPER
LEVEL IMPULSES WILL REMAIN WELL NORTH OF THE FORECAST AREA AND
AIRMASS MOISTURE WILL CONTINUE TO BE MINIMAL. TEMPERATURES ARE
FORECAST TO BE A DEGREE OR SO WARMER THAN THIS AFTERNOON.
&&
.LONG TERM...THURSDAY THROUGH TUESDAY
ISSUED AT 253 PM MDT TUE JUL 16 2013
VERY BROAD...FLAT LONG WAVE RIDGE OVER THE GREAT LAKES WILL
RETROGRESS TO THE PACIFIC COAST BY 12Z FRIDAY AND INCREASE SOMEWHAT
IN AMPLITUDE. GFS AND ECMWF BOTH SHOW THIS TREND. RESULT IS THAT
WEAK NORTHWESTERLY FLOW DEVELOPS OVER OUR CWA ON THURSDAY AND
FRIDAY ALLOWING A COLD FRONT TO MOVE ACROSS THE AREA. THIS WILL DROP
TEMPERATURES A BIT AND RESULT IN CHANCES FOR SCATTERED TSTM
DEVELOPMENT. UNCERTAINTY IN THE EXACT LOCATION OF THE RIDGE...THE
STRENGTH OF THE NORTHWESTERLY FLOW EAST OF IT...AND THE POSITION AND
TIMING OF SHORT WAVES EMBEDDED IN THIS FLOW ALL LEAD TO SUBSTANTIAL
UNCERTAINTY IN THE FORECAST FOR THE WEEKEND AND BEYOND. STAYED CLOSE
TO GUIDANCE WITH TEMPS AND PROBS.
&&
.AVIATION...FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON
ISSUED AT 253 PM MDT TUE JUL 16 2013
MAINLY VFR CONDITIONS WILL CONTINUE THROUGH THE PERIOD.
WEAK COLD FRONT AND SFC TROF WILL BRING NORTHERLY WINDS TO NE WY AND
NW SD THIS AFTN. FRONT WILL BECOME STNRY AND BECOME MORE DIFFUSE. AN
ISOLATED TSTM OR TWO POSSIBLE VCNTY OF THE FRONT THIS AFTN OVER
NORTHERN PORTIONS OF NE WY AND NW SD. SOUTHERLY SFC FLOW WILL
ENCOMPASS THE ENTIRE FCST AREA BY WED AFTN WITH VFR CONDS
CONTINUING.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
SHORT TERM...CARPENTER
LONG TERM...BARBER
AVIATION...BARBER
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
301 PM CDT TUE JUL 16 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 300 PM CDT TUE JUL 16 2013
CURRENTLY AS OF 20Z...
WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED AN UPPER LOW
JUST OFF THE NORTHERN CALIFORNIA COAST...TROUGHING OVER SASKATCHEWAN
AND MANITOBA...AND A 600 DAM SUBTROPICAL HIGH NEAR SOUTH BEND
INDIANA. 500MB HEIGHTS ARE 2-3 STANDARD DEVIATIONS ABOVE NORMAL FROM
THE FORECAST AREA EASTWARD INTO NEW ENGLAND. DESPITE THE HIGH 500MB
HEIGHTS...850MB TEMPS AT 12Z WERE GENERALLY 17-18C PER SOUNDING
DATA. PLENTY OF SUNSHINE HAS ALLOWED FULL MIXING TO 850MB...YIELDING
TEMPERATURES IN THE UPPER 80S TO MID 90S. ACCOMPANYING THE
SUBTROPICAL HIGH IS PLENTY OF DEEP MOISTURE...NOTED BY PRECIPITABLE
WATER VALUES OF 1.75 TO 2 INCHES FROM EASTERN OKLAHOMA INTO THE
FORECAST AREA. ITS WORTH NOTING THAT THE 12Z GRB SOUNDING
PRECIPITABLE WATER VALUES OF 2.07 INCHES IS AT THE 99TH PERCENTILE.
THIS DEEP MOISTURE IS ALSO REFLECTED AT THE SURFACE WITH DEWPOINTS
IN THE UPPER 60S/LOWER 70S...A LITTLE LOWER THAN AT 15Z DUE TO
MIXING AND DRIER SOILS. PLENTY OF CUMULUS HAS DEVELOPED IN THIS
MOIST AIRMASS. DESPITE HIGHER 500MB HEIGHTS TODAY COMPARED TO
YESTERDAY...THE HIGHER PRECIPITABLE WATER VALUES COMPARED TO MODEL
FORECASTS FROM YESTERDAY AND DAYTIME INSTABILITY HAS LED TO SOME
SHOWER DEVELOPMENT. TO THE NORTHWEST...A COLD FRONTAL BOUNDARY
ACCOMPANYING THE SOUTH CENTRAL CANADA TROUGH STRETCHED FROM
NORTHWEST ONTARIO BACK INTO THE BLACK HILLS OF SOUTH DAKOTA.
SYNOPTIC OVERVIEW...
THE SUBTROPICAL HIGH LOOKS TO SLOWLY DRIFT SOUTH DURING THE NEXT 24
HOURS IN RESPONSE TO THE SOUTH CENTRAL CANADA TROUGH PUSHING EAST
AND FLATTENING THE RIDGE. AS THIS OCCURS...THE COLD FRONTAL BOUNDARY
LOOKS TO LAY UP EAST TO WEST FROM NEAR THE NORTH DAKOTA/SOUTH DAKOTA
STATE LINE INTO UPPER MICHIGAN.
TONIGHT...
DIURNAL CUMULUS CLOUDS AS WELL AS ANY SHOWER ACTIVITY WILL DISSIPATE
THIS EVENING WITH LOSS OF HEATING...AND THEN THE REST OF NIGHT
SHOULD BE MOSTLY CLEAR. ANY POTENTIAL FOR ELEVATED CONVECTION LOOKS
TO OCCUR WELL OFF TO OUR NORTH ALONG THE FRONTAL BOUNDARY. A WARM
AND MUGGY NIGHT IS LIKELY AS DEWPOINTS JUMP BACK UP WITH LOSS OF
MIXING.
WEDNESDAY...
WITH A SOUTHWEST SURFACE FLOW AND THE COLD FRONTAL BOUNDARY STILL
OFF TO OUR NORTH...ANTICIPATING ANOTHER DRY DAY. ADDITIONALLY...
16.12Z NAM/GFS PRECIPITABLE WATER FORECASTS SUGGEST SLIGHTLY DRIER
VALUES IN THE 1.5 TO 1.8 INCH RANGE. THESE DRIER PRECIPITABLE WATER
VALUES SUPPORT A DRIER FORECAST...IN AGREEMENT TOO WITH THE 16.12Z
NAM AND HIRES-ARW. SHOULD SEE DEWPOINTS MIX DOWN A LITTLE MORE DUE
TO THOSE LOWER VALUES AND SOILS CONTINUING TO DRY OUT. 850MB TEMPS
ARE PROGGED SLIGHTLY WARMER THAN TODAY...18-19C...SO WE SHOULD BE
ABLE TO TACK ON 1-2F FOR HIGHS COMPARED TO TODAY. WITH THE
DEWPOINTS MIXING OUT...ANTICIPATING HEAT INDICES IN THE 95-102F
RANGE FOR A MAX.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 300 PM CDT TUE JUL 16 2013
SYNOPTIC OVERVIEW...
MODELS REMAIN IN GOOD AGREEMENT SHOWING THE SUBTROPICAL HIGH
CONTINUING TO GET SUPPRESSED TO THE SOUTH...IN RESPONSE TO TROUGHING
EVENTUALLY DEVELOPING OVER THE WESTERN GREAT LAKES BY SATURDAY. THIS
TROUGHING IS A COMBINATION OF TWO FEATURES:
1. THE CURRENT UPPER LOW OFF THE NORTHERN CALIFORNIA COAST DROPPING
THROUGH THE AREA AS A SHORTWAVE TROUGH LATE FRIDAY.
2. A POTENT TROUGH DROPPING THROUGH CENTRAL CANADA ON FRIDAY AND
POSSIBLY PHASING WITH THE AFOREMENTIONED SHORTWAVE TROUGH.
THE FORECAST AREA GENERALLY LOOKS TO STAY IN A NORTHWEST FLOW
HEADING INTO EARLY NEXT WEEK ACCORDING TO THE 16.12Z GFS/ECMWF.
HAZARDS...
EARLIER TODAY ISSUED A HEAT ADVISORY THROUGH FRIDAY. PART OF THE
UPGRADE WAS RELATED TO HOW QUICKLY WE WARMED THIS MORNING...
DEWPOINTS TAKING LONGER TO MIX OUT THAN EXPECTED...SLIGHTLY WARMER
TEMPERATURES THAN PREVIOUSLY FORECAST FOR WEDNESDAY THROUGH
THURSDAY...AND CONCERN FRIDAY WILL BE WARMER TOO. HEAT INDICES
GENERALLY SHOULD RANGE BETWEEN 95-100 EACH DAY ACROSS THE ENTIRE
FORECAST AREA...UNTIL THE FRONTAL PASSAGE FRIDAY...WITH VALLEY
LOCATIONS LIKELY AT OR ABOVE 100. NORMALLY 100 DEGREES IS THE
CRITERIA FOR HEAT ADVISORY...BUT IF A LONG DURATION EVENT OF 4 OR
MORE DAYS OCCUR WITH SLIGHTLY BELOW 100 DEGREE READINGS...AN
ADVISORY CAN BE ISSUED. ONLY TAYLOR COUNTY IS NOT IN A HEAT ADVISORY
BECAUSE OF CONVECTION CONCERNS WED NIGHT THROUGH FRIDAY.
CANNOT RULE OUT SOME SEVERE WEATHER ACROSS TAYLOR COUNTY THURSDAY
NIGHT OR POSSIBLY ON THE FRONT ON FRIDAY...BUT CONFIDENCE OF
PRECIPITATION IS LOWER AS DISCUSSED IN THE DAILY DETAILS BELOW.
DAILY DETAILS...
WEDNESDAY NIGHT THROUGH FRIDAY...
CONFIDENCE CONTINUES TO DECREASE OF PRECIPITATION AFFECTING THE
FORECAST AREA. THERE ARE NUMEROUS ISSUES THAT POINT TO A DRIER
FORECAST MORE LIKELY:
1. LOOKING AT ELEVATED CONVECTION POTENTIAL WEDNESDAY NIGHT THROUGH
THURSDAY NIGHT...THE 16.12Z NAM/ECMWF POINT THE NOSE OF THE 850MB
MOISTURE TRANSPORT NORTH OF THE FORECAST AREA...AND BY THURSDAY
NIGHT EVEN NORTHEAST OF LAKE SUPERIOR.
2. NOT CONNECTED TO A DRIER FORECAST MORE LIKELY...BUT THE GFS IS
PRODUCING WAY TOO MUCH PRECIPITATION IN THIS VERY WARM AND HUMID
ENVIRONMENT. ITS ALMOST LIKE IT CANNOT THE INSTABILITY. THIS
PRECIPITATION FEEDS BACK INTO OTHER FIELDS LIKE 850MB MOISTURE
TRANSPORT...MAKING THAT UNUSABLE.
3. AS THE FRONT AND SHORTWAVE APPROACH FRIDAY...THERE IS A DEFINITE
WARM SURGE AT 800MB COMING ACROSS THE AREA ON TOP OF THE FRONT. THIS
WARM SURGE COULD EFFECTIVELY CAP CONVECTION...BRINGING THE FRONT
THROUGH DRY. THE 16.12Z NAM/ECMWF DEPICT ISOLATED/SCATTERED
DEVELOPMENT AT MOST.
4. FRONTAL TIMING IS A BIG ISSUE...WITH MODELS SUGGESTING THE COLD
FRONT IS INTO LA CROSSE AT 18Z FRIDAY. DRY CONDITIONS ARE LIKELY
ONCE THE FRONT PASSES.
GIVEN ALL OF THE ABOVE ISSUES...HAVE SHIFTED PRECIPITATION CHANCES
FARTHER NORTH WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...AND KNOCKED
PRECIPITATION CHANCES DOWN FOR FRIDAY. PRECIPITATION STILL SEEMS
LIKELY TO IMPACT TAYLOR AND POSSIBLY CLARK COUNTIES DURING THIS TIME
FRAME...THOUGH.
TEMPERATURES ARE TRICKY TOO. GIVEN HOW WARM WE GOT TODAY AND THE
AIRMASS CONTINUING TO MODIFY...THINKING EACH DAY SHOULD BE JUST
SLIGHTLY WARMER THAN THE PREVIOUS. RAISED HIGHS THURSDAY AND
FRIDAY...AND DEPENDING ON FRONTAL TIMING FRIDAY COULD BE THE WARMEST
AS THAT WARM SURGE OF AIR MENTIONED IN POINT 3 ABOVE COMES IN.
FRIDAY NIGHT THROUGH TUESDAY...
HIGH PRESSURE LOOKS TO BUILD INTO THE FORECAST AREA FOR FRIDAY NIGHT
THROUGH SATURDAY NIGHT BEHIND THE FRONT...PROVIDING COOLER AND DRIER
CONDITIONS. STILL MAINTAINED A 20 PERCENT CHANCE IN THE EVENING IN
THE SOUTHEASTERN PORTION OF THE FORECAST AREA IN THE EVENT
CONVECTION/FRONT IS SLOWER. AS WE HEAD INTO SUNDAY AND THROUGH EARLY
NEXT WEEK...FORECAST BECOMES A BIT MORE PROBLEMATIC. MODELS ARE
SHOWING A VARIETY OF SHORTWAVES DROPPING THROUGH THE NORTHWEST
FLOW...WHILE AT THE SAME TIME 500MB HEIGHTS ARE RISING WITH WARM
ADVECTION IN THE LOWER LEVELS. THIS BECOMES A FAVORABLE PATTERN FOR
MULTIPLE ROUNDS OF CONVECTION. HAVE 20 PERCENT CHANCES IN THE
FORECAST FOR SUNDAY OVER WESTERN PORTIONS OF THE FORECAST
AREA...WHICH THEN EXPAND EAST AND BEGIN TO INCREASE ACROSS THE REST
OF THE AREA FOR SUNDAY NIGHT THROUGH TUESDAY. WE MAY HAVE TO WATCH
TEMPERATURES AGAIN AS WE APPROACH TUESDAY AS WELL...WITH THE
16.00Z/16.12Z ECMWF BRINGING 850MB TEMPS UP TO 24C WEST OF THE MS
RIVER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1200 PM CDT TUE JUL 16 2013
OVERALL VFR CONDITIONS EXPECTED THROUGH WEDNESDAY AFTERNOON. WITH
THE VERY HUMID AIRMASS IN PLACE...COULD SEE SOME LIGHT FOG
DEVELOPING OVERNIGHT BUT NOT EXPECTING ANYTHING LESS THAN 5-6SM.
OTHERWISE...DAYTIME HEATING/INSTABILITY WILL LEAD TO EXPANSIVE
CUMULUS FIELD. CANNOT RULE OUT A STRAY SHRA/TS...BUT WITH NO REAL
FORCING MECHANISM...NOT CONFIDENT ENOUGH TO PUT IN THE BODY OF THE
KRST/KLSE TAF RIGHT NOW.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...HEAT ADVISORY UNTIL 7 PM CDT FRIDAY FOR WIZ029-032>034-041>044-
053>055-061.
MN...HEAT ADVISORY UNTIL 7 PM CDT FRIDAY FOR MNZ079-086>088-094>096.
IA...HEAT ADVISORY UNTIL 7 PM CDT FRIDAY FOR IAZ008>011-018-019-029-
030.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
240 PM CDT TUE JUL 16 2013
.TONIGHT AND WEDNESDAY - CONFIDENCE...MEDIUM TO HIGH
HOISTED HEAT ADVISORY WITH LIKELIHOOD OF DAYTIME HEAT INDICES
REACHING 95 TO 100 THROUGH FRIDAY. WARM AND TROPICAL NIGHT WITH ANY
LINGERING CU/ISOLD SHRA OR TSRA DISSIPATING THIS EVENING. 6000 METER
HEIGHT CONTOUR INTO SE WI PER RUC ANALYSIS. GREATER COVERAGE OF TSRA
ON NW PERIPHERY OF THE RIDGE. STILL THINK THERE IS POTENTIAL FOR
ISOLATED DEVELOPMENT ALONG THE LAKE BREEZE BOUNDARY INTO THE EVENING
HOURS. 925 TEMPS AROUND 25-26C WEDNESDAY SO UPPER 80S/LOWER 90S LOOK
GOOD WITH TROPICAL DEW POINTS IN THE MID 70S. WILL CARRY A VERY
SMALL POP FOR THE AFTERNOON HOURS TO ACKNOWLEDGE A BLEND OF ALL THE
MODEL SOLUTIONS. A TRIGGER MAY BE HARD TO COME BY.
.WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...FORECAST CONFIDENCE IS
MEDIUM TO HIGH.
THE BIG SURFACE HIGH PRESSURE SYSTEM WILL BE DRIFTING TO THE
SOUTH WITH TIME. BY THURSDAY WE/LL START TO GET INTO A BETTER
SOUTHWEST GRADIENT FLOW BETWEEN THE HIGH TO THE SOUTH AND THE
APPROACHING COLD FRONT/TROUGH TO THE NORTHWEST. WILL ONLY CARRY
SOME SMALL POPS ACROSS MY FAR NORTH FOR ANYTHING THAT MAY SNEAK IN
WITH THE RING OF FIRE GETTING CLOSER. LOOK FOR HIGHS ON THURSDAY
AROUND 90 MOST PLACES WITH HEAT INDICES APPROACHING OR REACHING
100 IN SOME SPOTS.
.FRIDAY AND FRIDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM TO HIGH.
THE HEAT WILL REMAIN IN PLACE WITH FRIDAY NOW LOOKING A TOUCH
WARMER. 925MB TEMPS ON FRIDAY WILL BE PUSHING 26C IN A NARROW
WEDGE AHEAD OF THE APPROACHING FRONT...WHICH IS WARMER THAN
PREVIOUS RUNS. CLOUDS WILL BE INCREASING...SO WE WON/T REALIZE
THAT FULL POTENTIAL OF HEAT IF WE HAD GOOD MIXING WITH SUNSHINE.
HEAT INDICES AGAIN 95 TO 98. THE TIMING OF THE FRONT HASN/T CHANGED
MUCH WITH THE NEW RUNS...STILL REACHING THE WI/IL BORDER BY OR
SHORTLY AFTER 00Z SAT.
IT APPEARS THE BEST CHANCE FOR THUNDERSTORMS...AND SOME MAY BE
SEVERE...WITH THE FRONT WILL BE ACROSS THE EASTERN FORECAST AREA.
THE ORIENTATION OF THE ADVANCING FRONT WITH THE LAKE SHORE WILL
RESULT IN A MOVING TRIPLE POINT OF CONVERGENCE WHERE THE COLD
FRONT INTERSECTS THE STATIONARY COOL LAKE BNDRY. THE LAKE WILL
ESSENTIALLY BE ANOTHER LLV COLD FRONT WITH WARM ADVECTION/LIFT
OCCURRING JUST AHEAD OF THE FRONT...OVER THE COOLER DOME OF THE
LAKE. UPWELLING WITH THE INCREASING SOUTHWEST WINDS MAY HELP TO
ENHANCE THE BAROCLINIC ZONE. THE CIPS ANALOGS SHOW THE EAST WITH
THE BIGGEST THREAT FOR SEVERE WEATHER...MAINLY WIND AND HAIL. BACK
TO THE WEST TOWARD MADISON...THERE IS SOME LOW LEVEL CAPPING THAT
MAY BE HARD TO BUST...SO THE SEVERE THREAT DIMINISHES AS YOU GET
TO MADISON AND POINTS WEST.
THE RAIN SHOULD BE EXITING QUICKLY DURING THE EVENING WITH DRY
CONDITIONS RETURNING AFTER MIDNIGHT.
.SATURDAY AND SUNDAY...FORECAST CONFIDENCE IS HIGH.
A MUCH COOLER AND DRIER AIRMASS RETURNS FOR THE WEEKEND BRINGING
VERY PLEASANT TEMPERATURES. LOOK FOR HIGHS IN THE 70S AND NO RAIN.
.MONDAY AND TUESDAY...FORECAST CONFIDENCE IS MEDIUM.
WARM ADVECTION KICKS IN FOR MONDAY NIGHT INTO MONDAY AHEAD OF AN
APPROACHING LOW PRESSURE FROM THE NORTHWEST. THE WAA AND LOW
PRESSURE WILL BRING ANOTHER CHANCE FOR SHOWERS AND STORMS...ALONG
WITH SOME WARMER TEMPS.
&&
.AVIATION/00Z TAFS/...BKN VFR CU FIELD WILL DISSIPATE DIURNALLY ONCE
AGAIN THIS EVENING. VRY ISOLD TSRA THREAT INTO THE EARLY EVENING.
WITH LIGHT WIND REGIME PATCHY FOG DEVELOPMENT LOOKS REASONABLE
TONIGHT AS SUGGESTED BY MOS. LIKELY TO SEE MORE CU WEDNESDAY WITH
POTENTIAL FOR AN ISOLATED TSRA. ALTHOUGH MODEL COVERAGE AND
CONSENSUS NOT TOO CONVINCING.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...HEAT ADVISORY UNTIL 7 PM CDT FRIDAY FOR WIZ046-047-056-057-062-
063-067-068.
LM...NONE.
&&
$$
TONIGHT/WEDNESDAY AND AVIATION/MARINE...COLLAR
WEDNESDAY NIGHT THROUGH TUESDAY...DAVIS