Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/11/13
AREA FORECAST DISCUSSION
NWS TUCSON AZ
250 AM MST TUE JUL 9 2013
.SYNOPSIS...HIGH PRESSURE ALOFT WILL BE NEAR THE FOUR CORNERS REGION
THIS WEEK. THUNDERSTORM COVERAGE WILL INCREASE THIS WEEK AS THE FLOW
BECOMES MORE FAVORABLE TO PUSH STORMS INTO VALLEY LOCATIONS AND
DEEPER MOISTURE ADVANCES FROM THE SOUTH AND SOUTHEAST. EXPECT
SOMEWHAT LESS COVERAGE OF THUNDERSTORMS BY SUNDAY FOLLOWED BY
ANOTHER INCREASE IN THUNDERSTORMS EARLY NEXT WEEK.
&&
.DISCUSSION...EXPANSIVE MCS EXTENDED FROM SRN SONORA INTO SRN ARIZONA
EARLY THIS MORNING. FAIRLY WIDESPREAD COVERAGE OF SHOWERS PRODUCING
LIGHT RAINFALL...AND A FEW THUNDERSTORMS...WERE ONGOING ACROSS SE
AZ. THIS ACTIVITY AS PER THE 09/07Z RUC HRRR WILL MOVE WWD ACROSS
THE AREA THRU MID-MORNING...THEN DECREASE IN COVERAGE BY LATE
MORNING ACROSS WRN PIMA COUNTY. THEREAFTER...ADDITIONAL SHOWERS AND
THUNDERSTORMS ARE PROGGED TO DEVELOP EARLY THIS AFTERNOON MAINLY
ACROSS THE MOUNTAINS AND ACROSS THE TOHONO OODHAM NATION. ADDITIONAL
SHOWERS AND THUNDERSTORMS ARE THEN PROGGED TO ADVANCE SWWD FROM THE
WHITE MOUNTAINS LATE THIS AFTERNOON.
CONFIDENCE IN THIS FORECAST SCENARIO IS SOMEWHAT LOW GIVEN THE
ONGOING MCS. AT ANY RATE...THE OFFICIAL FORECAST DEPICTS SCATTERED
SHOWERS/TSTMS THIS AFTERNOON AND THIS EVENING FROM TUCSON EWD/SWD
WITH LESSER PRECIP COVERAGE ACROSS WRN PIMA COUNTY. HAVE MAINTAINED
A SLIGHT CHANCE OF SHOWERS/TSTMS ACROSS MUCH OF SE AZ LATE TONIGHT.
WED-FRI...
09/00Z GFS/ECMWF WERE SIMILAR WITH DEPICTING A POTENTIAL MID TO
HIGH-GRADE MONSOON REGIME. MID-LEVEL STEERING FLOW WILL BECOME
INCREASINGLY SELY THUR-FRI AS THE FOUR CORNERS UPPER HIGH MOVES INTO
THE CENTRAL CONUS PLAINS. SCATTERED TO PERHAPS NUMEROUS SHOWERS AND
TSTMS SHOULD OCCUR WED-FRI PARTICULARLY DURING THE AFTERNOON AND
EVENING HOURS. HAVE TRENDED POPS UPWARD GENERALLY ABOUT 10 PERCENT
EACH FORECAST PERIOD. GFS PWATS PROGGED TO BE NEAR 1.80 INCHES
ACROSS WRN PIMA COUNTY...AND ABOUT 1.30 INCHES NEAR THE NEW MEXICO
BORDER. THE INCREASED MOISTURE MAY PRODUCE SOME HEAVY DOWNPOURS
LEADING TO AT LEAST LOCALIZED FLOODING.
SAT-MON...
EXPECT THE COVERAGE OF SHOWERS/TSTMS TO REDUCE THIS WEEKEND AS MID-
LEVEL DRYING IS PROGGED VIA THE GFS/ECMWF. SUNDAY SHOULD EXPERIENCE
THE LEAST COVERAGE OF SHOWERS/TSTMS. THEREAFTER...PRECIP CHANCES
WILL INCREASE NEXT MONDAY AS AN UPPER LEVEL LOW PRESSURE SYSTEM
MOVES WWD ACROSS SRN TEXAS AND INTO CHIHUAHUA.
THE OFFICIAL FORECAST HIGH TEMP TODAY AT THE TUCSON INTERNATIONAL
AIRPORT IS 100 DEGREES. ACHIEVING 99 DEGREES OR COOLER WOULD END THE
CURRENT 38 CONSECUTIVE DAY STREAK OF TRIPLE DIGIT TEMPS AT TIA.
THEREAFTER...DAYTIME TEMPS WILL AVERAGE A FEW DEGS BELOW NORMAL
WED-FRI FOLLOWED BY SLIGHTLY WARMER DAYTIME TEMPS THIS WEEKEND.
&&
.AVIATION...VALID THRU 10/12Z...
SCT -SHRA AND ISOLD -TSRA THIS MORNING THEN SCT TSRA/SHRA THIS
AFTERNOON AND THIS EVENING. BRIEF WIND GUSTS OF 40-45 KTS INTO EARLY
THIS EVENING WITH THE STRONGEST TSRA. ISOLD-SCT -SHRA LATE TONIGHT
AND EARLY WEDNESDAY MORNING. OTHERWISE...VFR CONDITIONS AND SURFACE
WIND GENERALLY LESS THAN 10 KTS THRU EARLY WEDNESDAY MORNING.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...SCATTERED THUNDERSTORMS PRODUCING LOCALLY HEAVY
RAINFALL WILL OCCUR THROUGH SATURDAY. SOMEWHAT DRIER AIR WILL LESS
COVERAGE OF THUNDERSTORMS SUNDAY. THEREAFTER...AN UPPER LEVEL LOW
PRESSURE SYSTEM APPROACHING FROM THE EAST WILL PROVIDE INCREASED
THUNDERSTORM COVERAGE NEXT MONDAY. THE STRONGER THUNDERSTORMS INTO
EARLY NEXT WEEK WILL PRODUCE GUSTY AND ERRATIC WINDS. OTHERWISE...
NORMAL DIURNAL WIND TRENDS WILL OCCUR...WITH OCCASIONAL AFTERNOON
GUSTINESS DUE TO DAYTIME HEATING.
&&
.CLIMATE...THE HIGH TEMPERATURE AT TUCSON INTERNATIONAL AIRPORT
REACHED 105 DEGREES MONDAY. THUS...MONDAY BECAME THE 38TH
CONSECUTIVE DAY OF TRIPLE DIGIT TEMPS RECORDED AT TUCSON
INTERNATIONAL AIRPORT. THIS IS THE THIRD LONGEST STREAK ON RECORD
BEHIND 1987 AND 2005 (BOTH YEARS WITH 39 CONSECUTIVE DAYS).
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
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BF
AREA FORECAST DISCUSSION
NWS PUEBLO CO
333 PM MDT TUE JUL 9 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 253 PM MDT TUE JUL 9 2013
...A FEW STRONG STORMS POSSIBLE TOMORROW...
CURRENTLY...CONVECTION A BIT SLOW TO GET GOING...BUT SCT STORMS
DEVELOPING OVER THE MTS...AND LINE OF CU ALONG AND N OF HGWY 50 IS
STARTING TO SEE ISOLD CONVECTION DEVELOP. WILL CONTINUE TO SEE ISOLD
STORMS THIS AFTERNOON AND EVENING OVER THE PLAINS...WITH STORMS MOVING
TO THE S AND E. NOT EXPECTING A LOT OF RAIN WITH MOST OF THESE
STORMS...ALTHOUGH A COUPLE OVER THE FAR SERN GRASSLANDS COULD BE A LITTLE
MORE EFFICIENT RAIN PRODUCERS.
THE HIGH RES WRF AND HRRR CONTINUE TO SHOW THE POTENTIAL FOR
REDEVELOPMENT OF ISOLD SHOWERS AND STORMS OVER THE PALMER DVD AFTER
04Z TONIGHT...LINGERING INTO THE EARLY MORNING HOURS. AM SOMEWHAT
SKEPTICAL AS THERE IS NO REAL UPSTREAM DISTURBANCE TO KICK THINGS
OFF...BUT WILL MAINTAIN LOW/ISOLD POPS THROUGH TONIGHT FOR THAT AREA.
TOMORROW...THE PRECIP/POPS FORECAST GETS TRICKIER. THE GFS HAS VERY
LITTLE QPF OVER THE PLAINS TOMORROW...WHILE THE NAM HAS WIDESPREAD
PRECIP...ESPECIALLY OVER THE ERN PORTIONS OF OUR CWA. HOWEVER...EVEN
THE NAM HAS BACKED OFF ON THE EXTENT OF COOLER AIR MOVING INTO OUR
AREA. LATEST MOS GUIDANCE FOR KPUB IN IN THE MID TO UPPER 90S. THE
QUESTION IS TO WHAT EXTENT THE WEAK FRONTAL PUSH WILL MOVE INTO OUR
AREA. OUTSIDE THE FRONT AND MODEST UPSLOPE...THERE IS NOT MUCH OF A
TRIGGER IN THE FLOW ALOFT TO SUPPORT WIDESPREAD QPF. AM BEING A BIT
CAUTIOUS WITH POPS TOMORROW...KEEPING CHANCE POPS OVER THE PLAINS
IN THE AFTERNOON...BUT LATER SHIFTS MAY NEED TO DO SOME REDUCTIONS
IF THE MODELS CONTINUE A TREND TOWARDS FEWER STORMS. THERE STILL
SHOULD BE FAIRLY WIDESPREAD CONVECTION OVER THE ERN MTS...WITH LIGHT
S TO SE FLOW ACROSS THE PLAINS IN THE AFTERNOON. DEWPOINTS SHOULD BE
IN THE LOWER 50S TO POSSIBLY UPPER 50S CLOSER TO THE KS BORDER. THE
LIGHT WINDS AND INCREASED MOISTURE SHOULD KEEP TEMPS FROM RISING AS
HIGH AS MOS GUIDANCE SUGGESTS.
DEPENDING ON HOW FAR THE FRONTAL BOUNDARY MAKES IT INTO SE
CO...THERE ALSO COULD BE A MARGINAL THREAT OF SVR WX
TOMORROW...ESPECIALLY E OF I-25 AND N OF HGWY 50 IN THE LATE
AFTERNOON AND EARLY EVE. THE HIGHEST THREAT WILL BE OVER KIOWA
COUNTY LATE IN THE DAY...WHERE BULK SHEARS WILL APPROACH 40 KTS OR
SO AND MOISTURE WILL BE GREATEST. COULD SEE SOME HAIL FROM THE
STRONGEST STORMS...ALONG WITH GUSTY WINDS AND BRIEF HEAVY RAINFALL.
ROSE
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 253 PM MDT TUE JUL 9 2013
...UPSWING IN THUNDERSTORMS WEDNESDAY EVENING...WITH MONSOON CONTINUING
FOR THE NEXT SEVERAL DAYS...
INTERACTION OF BOUNDARY MOVING THROUGH THE PLAINS AND MONSOON
MOISTURE PROMISES AN UPSWING IN THUNDERSTORM ACTIVITY LASTING
INTO WEDNESDAY EVENING.
THEN...THURSDAY THROUGH SATURDAY...THE MONSOON REGROUPS OVER THE
MOUNTAINS...MAINLY AFFECTING AREAS ALONG AND WEST OF I-25. HIGH
PRESSURE CENTERS OVER EASTERN COLORADO AND WESTERN KANSAS DURING
THIS TIME...DIRECTING THE FLOW OF MOISTURE INTO THOSE AREAS.
BEGINNING SUNDAY...THE HIGH MAY SHIFT EAST FAR ENOUGH TO LET THE
MONSOON SPILL OUT ONTO THE PLAINS...BRINGING AN UPSWING IN
ACTIVITY TO THOSE AREAS.
PRIMARY CONCERNS OVER THE NEXT SEVERAL DAYS WILL BE THE IMPACT OF
HEAVY RAINS ON AREA BURN SCARS. IF HEAVY RAIN DEVELOPS OVER ANY OF
THE SCARS...FLASH FLOODING AND DEBRIS FLOWS WILL BE POSSIBLE. OTHER
CONCERNS THROUGH THE PERIOD WILL BE LIGHTNING...WIND GUSTS TO
AROUND 55 MPH AND LOCAL SMALL HAIL.
ITS STILL SEVERAL DAYS OFF...BUT THE GREATEST POTENTIAL FOR HEAVY
RAINFALL WOULD APPEAR TO MOVE IN OVER THE WEEKEND AS UPPER HIGH
PRESSURE SHIFTS OVER EASTERN COLORADO...ALLOWING MONSOONAL
MOISTURE INFLUX INTO WESTERN COLORADO ON THE WEST SIDE OF THE
HIGH. IN MANY CASES THE RAIN WILL BE BENEFICIAL...BUT THE RISK FOR
FLASH FLOODING AND DEBRIS FLOWS IN AND AROUND AREA BURN SCARS WILL
LIKELY INCREASE DURING THIS PERIOD. LW
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 253 PM MDT TUE JUL 9 2013
VFR CONDITIONS EXPECTED TO CONTINUE AT THE TAF SITES THROUGH
TOMORROW. AS MENTIONED IN PREVIOUS DISCUSSION...STILL THE THREAT OF
ISOLD TS THROUGH EARLY EVENING...AND POSSIBLY LINGERING THROUGH
TONIGHT OVER THE PALMER DVD AND VC KCOS. TOMORROW...SHOULD SEE
A BETTER CHANCE OF STORMS ESPECIALLY ALONG I-25 AND EWD...FROM 18Z
THROUGH 03Z WED EVE. A FEW OF THESE STORMS COULD BE ON THE STRONG
SIDE..ESPECIALLY E OF I-25 AND N OF HGWY 50. HAIL UP TO AN INCH AND
LOCALLY HEAVY RAINFALL...ALONG WITH WIND GUSTS TO 50 KTS...WILL BE
POSSIBLE WITH THE STRONGEST STORMS TOMORROW. ROSE
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...ROSE
LONG TERM...LW
AVIATION...ROSE
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1048 AM MDT TUE JUL 9 2013
.UPDATE...WATER VAPOR IMAGERY...MORNING RAOBS AND INTEGRATED
PRECIPITABLE WATER PRODUCTS ALL INDICATE A MUCH DRIER AIRMASS OVER
THE FORECAST AREA TODAY. MODEL SOUNDINGS FROM THE NAM AND RAP ALSO
SHOW MID-LEVEL CAPPING OVER MOST OF THE PLAINS THROUGH THE
AFTERNOON. THE EXCEPTION TO THIS IS EAST OF A LIMON-AKRON LINE
WHERE 1000-1500 J/KG OF CAPE WILL BE PRESENT DURING THE EARLY
EVENING. MOUNTAIN AREAS SHOULD STILL SEE ISOLATED THUNDERSTORMS
THIS AFTERNOON...BUT THE SHOWERS WILL RAPIDLY EVAPORATE AS THEY
MOVE OFF THE FOOTHILLS...SIMILAR TO YESTERDAY AFTERNOON. WILL
UPDATE THE FORECAST TO REMOVE MENTION OF THUNDERSTORMS ON THE
PLAINS THIS AFTERNOON AND EVENING. WILL HOLD ONTO ISOLATED
THUNDERSTORMS OVER THE EASTERN TIER OF COUNTIES AFTER 00Z.
HOT TEMPERATURES ARE GOING TO BE THE MAIN STORY THIS
AFTERNOON...AS WE HAVE ALREADY REACHED 92 AT KDEN. THE RECORD FOR
THE DAY IS 98...WHICH MAY TUMBLE DURING THE MID-LATE AFTERNOON.
&&
.AVIATION...NO AVIATION IMPACTS THROUGH THIS AFTERNOON AND
EVENING. WINDS WILL SWITCH TO LIGHT AND NORTHERLY DURING THE
AFTERNOON...AHEAD OF A MORE SIGNIFICANT FRONTAL PUSH LATER THIS
EVENING.
&&
.HYDROLOGY...AFTERNOON SHOWERS WILL ONLY PRODUCE LIGHT AMOUNTS OF
RAIN...SO NO PROBLEMS ARE EXPECTED.
&&
.PREV DISCUSSION... /ISSUED 249 AM MDT TUE JUL 9 2013/
SHORT TERM...AN UPPER LEVEL HIGH WILL BE OVER SWRN CO WITH WEAK
WNW FLOW ALOFT ACROSS NRN CO. WATER VAPOR IMAGERY SHOWS BEST PLUME
OF SUBTROPICAL MOISTURE ACROSS SRN CO WHICH IS FCST TO STAY IN THE
SAME GENERAL AREA. AT THE SFC A WK PRE FNTL BNDRY WILL MOVE ACROSS
NERN CO TODAY AND FLUSH OUT LOW LVL MOISTURE EXCEPT POSSIBLY OVER
THE FAR NERN CORNER. AT THIS TIME TSTM THREAT OVER NERN CO LOOKS
RATHER ISOLD AND HIGH BASED. OVER THE HIGHER TERRAIN WILL KEEP IN
WDLY SCT TSTMS. AS FOR HIGHS READINGS WILL RISE ANOTHER FEW
DEGREES WITH TEMPS IN THE 95 TO 100 DEGREE RANGE OVER THE PLAINS.
RECORD HIGH AT DENVER IS 98 WHICH COULD BE TIED OR BKN.
FOR TONIGHT A CDFNT WILL MOVE ACROSS NERN CO OVERNIGHT AND BRING AN
INCREASE IN LOW LVL MOISTURE ALL THE WAY BACK INTO THE FOOTHILLS BY
12Z. AT THIS POINT REALLY CAN`T SEE ANYTHING TO ENHANCE CONVECTION
HOWEVER IF A WK DISTURBANCE WERE TO MOVE ACROSS THEN THAT COULD
CHANGE THINGS DRAMATICALLY. FOR NOW WILL JUST KEEP LOW POPS IN
OVERNIGHT ACROSS THE PLAINS.
LONG TERM...NO SIGNIFICANT CHANGES AT THIS TIME. ON WEDNESDAY
LOW LEVEL MOISTURE WILL INCREASE ACROSS NORTHEAST COLORADO
FOLLOWING THE PASSAGE OF A WEAK COLD FRONT. SFC WINDS WILL ALSO
BACK AROUND TO THE SE WHICH WOULD LEAD TO THE DEVELOPMENT OF A
DENVER CYCLONE IN THE LATE AFTN/EVNG. MDLS VARY GREATLY REGARDING
THE FCST QPF AMOUNTS BUT THEY ALL INDICATE RAINFALL. IN
ADDITION...SHEAR PROFILE INDICATIVE OF SOME SEVERE TSTM POTENTIAL
AS WELL. FCST CAPES FM THE GFS BUFFER SOUNDINGS AROUND 1000 J/KG
AT KDEN AROUND 21Z...WITH 1600 J/KG FM THE NAM12. PW VALUES FM
BOTH SOUNDINGS IN EXCESS OF ONE INCH...SO WILL SIDE WITH THE
HEAVIER QPF AMOUNTS FM THE GFS BUFFER SOUNDINGS. SIMILAR VALUES
FCST FOR THE NERN PLAINS OF CO AS WELL. ON THURSDAY THE AMS WILL
BE DRIER ALONG THE URBAN CORRIDOR...WITH BETTER POTENTIAL OVER THE
NERN PLAINS WHERE THE BEST LOW LEVEL MOISTURE WILL BE. THE RIDGE
ITSELF WILL MOVE FM THE FOUR CORNERS REGION 00Z THU TO THE
OKLAHOMA/TEXAS PANHANDLES BY 00Z FRI. THE CENTER OF THE RIDGE WILL
SHIFT A BIT FURTHER EASTWARD BY THE WEEKEND. BEST CHC OF TSTMS
DURING THE WEEK WILL BE WEDNESDAY AFTN/EVNG...MAYBE A LITTLE LESS
COVERAGE ON THURSDAY. FRIDAY THROUGH SUNDAY...SUBTROPICAL MOISTURE
WILL INCREASE ACROSS WRN AND NRN CO AND FRIDAY THROUGH SUNDAY AS
WILL THE CHC OF THUNDERSTORMS. THE MOISTURE IS PROGGED TO MOVE FM
BAJA INTO CO IN THAT TIME. HEAVY RAIN POTENTIAL WILL EXIST ACROSS
THE CWFA EACH AFTN/EVNG...ESPECIALLY OVER THE WEEKEND...WITH THE
STORMS.
AVIATION...SFC WINDS WERE SSW EARLY THIS MORNING BUT SHOULD
BECOME LIGHT WNW AROUND 14Z AND THEN MORE NNE BY 17Z. BY LATE AFTN
THEY MAY BECOME MORE ELY AND THEN SELY BY 01Z. AT THIS TIME TSTM
THREAT LOOKS LOW THRU THIS AFTN INTO THE EARLY EVENING HOURS SO
WILL NOT MENTION IN THE TAF.
FOR TONIGHT A COLD FRONT WILL MOVE INTO THE AREA AFTER MIDNIGHT.
THERE IS SOME POTENTIAL FOR STRATUS IN THE 12Z-15Z TIMEFRAME ON
WED.
HYDROLOGY...ISOLD TO WIDELY SCATTERED THUNDERSTORMS WILL DEVELOP
THIS AFTERNOON HOWEVER THEY WILL BE RATHER HIGH BASED SO RAINFALL
AMOUNTS SHOULD BE UNDER A QUARTER INCH.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...DANKERS
LONG TERM....99
AVIATION...DANKERS
AREA FORECAST DISCUSSION
NWS TAUNTON MA
750 PM EDT WED JUL 10 2013
.SYNOPSIS...
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED AT TIMES THROUGH
AT LEAST FRIDAY...BRINGING LOCALIZED HEAVY RAINFALL/FLOODING. LESS
HUMID WEATHER ARRIVES THIS WEEKEND. THE MAJORITY OF THE TIME WILL
BE DRY...BUT A FEW SPOT SHOWERS/THUNDERSTORMS WILL STILL BE
POSSIBLE. VERY WARM AND HUMID WEATHER WILL MAKE A RETURN FOR THE
START OF THE NEXT WORK WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
730 PM UPDATE..
SHOWERS AND THUNDERSTORMS GRADUALLY DISSIPATING...TO WHICH THE
LATEST NEAR-TERM HRRR FORECAST GUIDANCE IS MODELING WELL. EXPECT
MUCH OF THE ACTIVITY TO END OVER THE NEXT COUPLE OF HOURS AND THE
REMAINDER OF THE EVENING TO BE MAINLY DRY.
IF BELIEVING THE HRRR THEN ACTIVITY APPROACHING FROM THE OHIO
RIVER VALLEY SHOULD DISSIPATE PRIOR TO ARRIVAL IN THE HUDSON RIVER
VALLEY REGION. IR SATELLITE DOES EXHIBIT CLOUD TOP WARMING AS THE
BULK OF THE STORM ACTIVITY OVER THE EASTERN CONUS SHIFTS SOUTH AND
EAST TOWARDS THE BETTER AXIS OF MOISTURE AND INSTABILITY.
BUT ECHO THE PREVIOUS FORECASTER...SHOWERS AND THUNDERSTORMS ARE
CERTAINLY PLAUSIBLE DURING THE OVERNIGHT AS THE BOUNDARY LAYER
DECOUPLES AND WINDS INCREASE JUST ABOVE THE SURFACE INVERSION WITH
THE GRADUAL CLOSER APPROACH OF THE MID-LEVEL TROUGH AND SURFACE
COLD FRONT. LOCALIZED CONVERGENCE OF THE VERY MOIST ENVIRONMENT
/PWATS 2+ INCHES/ WITHIN A REGION OF ELEVATED INSTABILITY IS
LIKELY TO YIELD SOME ACTIVITY THAT COULD LEAD TO LOCALLY HEAVY
DOWNPOURS AND POTENTIAL FLOODING. 0-6 KM MEAN WIND IS AROUND 20 TO
30 MPH SUGGESTING A PROGRESSIVE FLOW...BUT WEAK CORFIDI VECTORS
SUGGEST THE POSSIBILITY OF BACK-BUILDING STORMS. THUS THE FLASH
FLOOD WATCH CONTINUES ACCORDINGLY. EVALUATING THE HRRR...THE BEST
ACTION MAY BE ALONG THE SOUTH-SHORE AND ACROSS THE CAPE AND
ISLANDS.
FOCUSING BACK TO THE VERY MOIST AIRMASS ACROSS THE REGION.
NUMEROUS LOCATIONS REPORTING LOW 70 DEWPOINTS...AND SURFACE
TEMPERATURES ARE NOT MUCH WARMER. WITH THE INVERSION DEVELOPING
AND COOLING AT THE SURFACE...ANTICIPATING FOG TO DEVELOP WITH
VISIBILITIES DOWN TO A QUARTER MILE OR LESS...ESPECIALLY FOR THE
SOUTH-SHORE AND FOR THOSE LOCATIONS WHICH RECEIVED RAIN EARLIER
TODAY. DENSE FOG ADVISORIES MAY BE NEEDED.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
TOMORROW...
SYNOPTIC SHORTWAVE WILL PUSH A COLD FRONT ACROSS SOUTHERN NEW
ENGLAND THROUGHOUT THE DAY TOMORROW. EXPECT IT TO BE OUT WEST BY THE
MID MORNING AND EVENTUALLY THROUGH THE REGION BY THE LATER EVENING
INTO THE OVERNIGHT HOURS. THIS FRONT WILL BE THE MAIN FOCUS FOR
CONVECTION TOMORROW.
CONTINUED TO KEEP THE FLASH FLOOD WATCH AND HAVE EXPANDED IT TO
INCLUDE THE EASTERN PORTION OF MASSACHUSETTS. THE REGION WILL
CONTINUE TO BE IN THE WARM MOIST AIRMASS AND WITH ONGOING CONVECTION
IN THE MORNING HOURS EXPECT THEM TO CONTINUE AND SPREAD EASTWARD
THROUGHOUT THE DAY. LOW CONFIDENCE ON ANY SEVERE POTENTIAL...HOWEVER
BELIEVE HEAVY DOWNPOURS ARE STILL THE MAIN THREAT THANKS TO HIGH
DEWPOINTS AND PWATS NEAR 2 INCHES. THE DIFFERENCE BETWEEN TOMORROW
AND TODAY IS THAT TOMORROW WILL HAVE A BETTER SOURCE OF LIFT AS WELL
AS MORE SHEAR...NEAR 20-30 KTS. STORMS WILL CONTINUE INTO THE EARLY
EVENING AND SHOULD WANE IN SEVERE POTENTIAL AFTER SUNSET.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
HEADLINES...
* HEAVY RAIN AND POSSIBLE FLOODING THURSDAY NIGHT INTO FRIDAY NIGHT
* AN UNCERTAIN WEEKEND FORECAST...LOOKING DRY BUT SHOWERS POSSIBLE
* RETURN OF HEAT AND HUMIDITY FOR THE BEGINNING OF THE WEEK
* SEASONABLE CONDITIONS AND WET WEATHER ANTICIPATED BY MIDWEEK
*/OVERVIEW AND MODEL CONSENSUS...
FORECAST SOLUTIONS SUCCINCT UPON A MID- TO UPPER-LEVEL TROUGH
STALLING AGAINST STRONGER RIDGING ACROSS THE WESTERN ATLANTIC. THE
GENERAL TREND IS FOR THE TROUGH TO UNDERGO FURTHER MATURITY TOWARDS
OCCLUSION AS A CLOSED COLD-CORE LOW...BIFURCATING FROM THE LONGWAVE
FLOW ALONG THE NORTHERN PERIPHERY OF THE BROADER RIDGE PATTERN
ACROSS THE CENTRAL CONUS.
BUT IT IS THE STRENGTH AND EVOLUTION OF THIS LOW THAT REMAINS FAIRLY
UNCERTAIN...THOUGH CONFIDENT IT WILL RETROGRADE SOUTH AND WEST
AROUND THE BROADER CENTRAL CONUS HIGH. ACCORDINGLY...SURFACE
OUTCOMES FOR THE WEEKEND AND BEYOND REMAIN UNCERTAIN.
RUN-TO-RUN CONSISTENCY HAS BEEN BEST WITH THE ECMWF...THE CANADIAN
HAS EXHIBITED DRAMATIC SHIFTS...WHILE THE GFS HAS WOBBLED IN
HANDLING POTENTIAL OUTCOMES. THE NAM/SREF IS JUST BEGINNING TO
FORECAST THE LOW MATURATION AND OCCLUSION...ROUGHLY CLOSE WITH THE
ECMWF. MAINTAINING CONTINUITY THROUGH ENSEMBLE MEMBERS AND WPC/HPC
FORECAST SEEMS TO BE THE BEST GUIDANCE TOWARDS FORECASTING THE LONG-
TERM.
*/DAY-TO-DAY DETAILS...
*/THURSDAY NIGHT INTO FRIDAY NIGHT...
THE ATMOSPHERE UNDERGOES A SQUEEZE ACROSS A MAJORITY OF SOUTHERN NEW
ENGLAND AS LOW-LEVEL CONVERGENCE PREVAILS ALONG THE STALLED SURFACE
FRONTAL BOUNDARY BENEATH FAVORABLE REGION OF ENHANCED ASCENT AHEAD
OF THE MAIN MID-LEVEL IMPULSE AND RIGHT-ENTRANCE REGION OF THE UPPER
LEVEL JET.
NOT CONVINCED ON A SEVERE WEATHER THREAT...INSTABILITY APPEARS LOW
TO NON-EXISTENT IN A REGION OF STRONG SHEAR /MAINLY UNI-
DIRECTIONAL IN THE LOW- TO MID-LEVELS...SOME SLIGHT TURNING AT THE
SURFACE/. MAIN CONCERN IS FLOODING WITH DEEP-LAYER ASCENT IN AN
ENVIRONMENT WITH PWATS RANGING 1.5 TO 2 INCHES. LIKELY POPS
WARRANTED. FLOOD WATCHES LIKELY TO BE EXTENDED THROUGHOUT THE
PERIOD FOCUSED ON ALL OF SOUTHERN NEW ENGLAND AS MUCH OF THE
REGION SHOULD BE SATURATED FROM TODAYS AND THURSDAYS RAINS.
ANTICIPATED CLOUDY AND WET CONDITIONS SHOULD KEEP HIGHS SLIGHTLY
BELOW SEASONABLE LEVELS...AND LOWS MILD OVERNIGHT. WINDS VARIABLE
BECOMING NORTHERLY IN WAKE OF THE FRONTAL BOUNDARY PASSAGE.
*/SATURDAY INTO SUNDAY...
WHILE TRENDS ARE EVIDENT...FORECAST GUIDANCE IS NOT SUCCINCT WITH
THE STRENGTH AND EVOLUTION OF THE CLOSED COLD-CORE LOW AROUND THE
BROADER CENTRAL CONUS HIGH. A VARIETY OF SURFACE OUTCOMES ARE
PLAUSIBLE...DEPENDENT ON THE LOCATION OF THE LOW AND ATTENDANT MID-
TO UPPER-LEVEL FLOW.
FEEL THE ENVIRONMENT SHOULD BE SLIGHTLY DRIER AND WILL ECHO THE
PREVIOUS FORECASTERS THINKING...HOPEFULLY STAYING DRY WITH THE
CHANCE OF DIURNALLY DRIVEN SHOWERS AND THUNDERSTORMS. MINOR
INSTABILITY AND WEAK SHEAR PROFILES RESULT IN A CONTINUED MAIN
THREAT OF HEAVY RAIN AND THE POSSIBILITY OF LOCALIZED FLOODING.
CONDITIONS REMAINING SEASONABLE WITH LIGHT AND VARIABLE SURFACE WIND
FIELDS.
*/MONDAY INTO TUESDAY...
WITH THE PREFERRED RETROGRESSION OF THE CLOSED COLD-CORE LOW SOUTH
AND WEST AROUND THE BROADER FLOW ASSOCIATED WITH THE HIGH...THE
OFFSHORE BERMUDA HIGH BUILDS BACK INTO THE REGION PERMITTING DRIER
AND WARMER CONDITIONS.
SOUTHWESTERLY SURFACE WINDS AND WARM-AIR ADVECTION ALOFT RESULTS IN
THE RETURN OF HOT AND HUMID CONDITIONS. EXPECT HIGHS TO GET INTO THE
LOW-90S. WILL GO WITH A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS
WITH POTENTIAL MINOR INSTABILITY AND UNI-DIRECTIONAL SOUTHWESTERLY
SHEAR.
*/WEDNESDAY INTO THE END OF THE WEEK...
SHOULD THE BERMUDA HIGH WEAKEN AND PUSH SOUTH...HEIGHTS WILL FALL
WITHIN THE MID-LEVELS ALLOWING THE RETURN OF THE NORTHERN STREAM OF
CYCLONIC FLOW...INCREASING CHANCES FOR DIURNALLY DRIVEN WEATHER AS
WEAK WAVES MOVE THROUGH THE LONGWAVE FLOW PATTERN...INVOKING SURFACE
AREAS OF LOW PRESSURE. WILL GO SLIGHT CHANCE TO CHANCE POPS FOR THE
PERIOD KEEPING CONDITIONS CLOSE TO SEASONABLE.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
.SHORT TERM...TODAY THROUGH THURSDAY...
MODERATE CONFIDENCE ON TRENDS...LOW CONFIDENCE ON TIMING.
SHRA AND ISOLATED TSRA TO DISSIPATE INTO THE EVENING HOURS. THERE
IS A PLAUSIBLE REFOCUS ALONG THE SOUTH-SHORE INCLUDING THE CAPE
AND ISLANDS. HAVE TEMPO GROUPS ACCORDINGLY...ALONG WITH VCSH FOR
THOSE TERMINALS POTENTIALLY CLOSE TO THE ACTION.
OTHERWISE...FOR THE OVERNIGHT PERIOD...THE FOCUS WILL BE LOWERING
CIGS AND DENSE FOG...WITH VISIBILITIES DOWN TO A QUARTER MILE OR
LESS /ESPECIALLY ALONG THE SOUTH-SHORE/. SIMILAR IMPACTS ARE
EXPECTED OVER TERMINALS WHICH RECEIVED RAIN EARLIER TODAY.
SOUTHWEST WINDS WITH GUSTS AROUND 20 KTS FOR THE SOUTH-SHORE
INITIALLY...SLACKENING SLIGHTLY THROUGH THE OVERNIGHT.
INTO THURSDAY...EXPECTING THE INCREASE OF SHRA/TSRA ALONG AND
AHEAD OF AN APPROACHING COLD FRONT. BUT UNCERTAINTY PREVAILS AS
TO HOW QUICKLY CIGS AND VSBYS IMPROVE AS SHRA/TSRA BUILD INTO THE
REGION. TREND IS FOR GRADUAL LIFTING OF IFR-LIFR TO LOW-END VFR.
THEREAFTER ACTIVITY WILL SLOWLY MOVE ACROSS SOUTHERN NEW ENGLAND.
STORMS DIRECTLY IMPACTING TERMINALS SHOULD RESULT IN LOW-END
VFR/MVFR CIGS WITH MVFR-IFR VSBYS... LOWER CONDITIONS FOR THE
CAPE/ISLAND TERMINALS WHICH MAY REMAIN SOCKED IN WITH LOWER CLOUDS
A MAJORITY OF THE DAY. SOUTHWEST WINDS BACKING OUT OF THE WEST-
NORTHWEST WITH COLD FRONTAL PASSAGE.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. WITH SOUTHWEST FLOW
HAVE HELD VSBYS AT IFR. ANTICIPATING IFR-LIFR CIGS TO FILL IN
QUICKLY.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. SCATTERED SHRA WILL
LINGER FOR THE FIRST FEW HOURS...THEN WILL KEEP IT DRY INTO
MORNING. CONDITIONS IMPROVING...WITH THE POSSIBILITY OF TSRA BY
MIDDAY...THUS MENTIONED VCTS.
OUTLOOK...THURSDAY NIGHT INTO MONDAY...
THURSDAY NIGHT INTO FRIDAY NIGHT...MODERATE CONFIDENCE.
SHRA/TSRA WILL BE ONGOING INITIALLY...LIFTING NORTH AND DISSIPATING
THROUGH THE PERIOD ACROSS SOUTHERN NEW ENGLAND. LOW-VFR/MVFR CIGS
WITH MVFR/LIFR VSBYS WITH +RA. NORTHERLY WINDS. FOG WILL LIKELY BE
AN ISSUE FOR THE SOUTH-COAST A MAJORITY OF THE PERIOD...POTENTIALLY
SPREADING ACROSS THE INTERIOR FOR THE EVENING PERIODS.
SATURDAY INTO SUNDAY...LOW CONFIDENCE.
PREVAILING VFR WITH LOW-END VFR CIGS. AN AFTERNOON SHRA/TSRA IS
POSSIBLE. POTENTIAL FOR DETERIORATING CONDITIONS OVERNIGHT WITH
MVFR/IFR CIGS AND POSSIBILITY FOR FOG. LIGHT AND VARIABLE WINDS.
MONDAY...MODERATE CONFIDENCE.
PREVAILING VFR WITH LOW-END VFR CIGS. WILL KEEP THE FORECAST PERIOD
DRY. WINDS VEERING OUT OF THE SOUTH-SOUTHWEST.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
.SHORT TERM...MODERATE TO HIGH CONFIDENCE.
THIS AFTERNOON...SHOWERS AND THUNDERSTORMS WILL MOVE FROM WEST TO
EAST ACROSS THE WATERS LATE THIS AFTERNOON. NEAR SHORE WATERS MAY
QUICKLY GUST TO 25KTS BUT LOW CONFIDENCE ON ISSUING A SCA.
OTHERWISE SEAS ARE AROUND 1-3FT.
TONIGHT-THURSDAY...CONTINUED SCA FOR THE OUTER WATERS TONIGHT AND
INTO TOMORROW. FEEL ITS MARGINAL AS OUTER WATERS MAY GET TO 5 FT.
WNA WAVE HAS BEEN TO AGGRESSIVE ON THE WAVE HEIGHTS RECENTLY SO
UNDERCUT THEM WITHIN THE FORECAST.
OUTLOOK...THURSDAY NIGHT INTO MONDAY...
THURSDAY NIGHT INTO FRIDAY NIGHT...
RAIN WITH EMBEDDED THUNDERSTORMS WILL STALL ACROSS THE WATERS EARLY
IN THE PERIOD...GRADUALLY LIFTING NORTH LATE. HEAVY RAIN AT TIMES
WILL LIKELY LEAD TO VISIBILITY RESTRICTIONS. WINDS WILL BE LIGHT AND
VARIABLE INITIALLY...BACKING OUT OF THE NORTH. THIS SHOULD ALLOW
SEAS OVER A MAJORITY OF THE WATERS TO REMAIN 5 FEET OR LESS. LOW
CONFIDENCE CONCERNING MARINE HEADLINES FOR ANY STORMS.
SATURDAY INTO MONDAY...
WHILE SHOWERS AND THUNDERSTORMS MAY BE POSSIBLE ALONG THE NEAR-SHORE
WATERS...FEEL WEATHER CONDITIONS WILL REMAIN BENIGN. PREVAILING
NORTHERLY WINDS WILL LESSEN DURING THE PERIOD...BECOMING LIGHT AND
VARIABLE PRIOR TO VEERING OUT OF THE SOUTH-SOUTHWEST. SEAS TO REMAIN
BELOW 5 FEET.
&&
.HYDROLOGY...
A SLOW MOVING COLD FRONT WILL CONTINUE TO APPROACH THE REGION
THURSDAY...STALLING OFFSHORE OF SOUTHERN NEW ENGLAND INTO FRIDAY
ALONG AND IN THE VICINITY OF WHICH THERE WILL BE A THE EXPECTATION
FOR HEAVY RAIN AND THUNDERSTORMS. WITH THE GROUND SATURATED...AND
THE POTENTIAL FOR CONTINUOUS HEAVY RAIN AND THUNDERSTORMS OVER ANY
ONE PARTICULAR AREA...LOCALIZED FLASH FLOODING IS POSSIBLE. AS
WITNESSED WITH STORMS OVER THE LAST COUPLED OF DAYS...STORMS HAVE
THE PROPENSITY OF PRODUCING AROUND 2 INCHES OF RAIN IN LESS THAN
AN HOUR. AS SUCH THE FLASH FLOOD WATCH HAS BEEN CONTINUED AND
EXPANDED EASTWARD.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...FLASH FLOOD WATCH THROUGH THURSDAY AFTERNOON FOR CTZ002>004.
MA...FLASH FLOOD WATCH THROUGH THURSDAY AFTERNOON FOR MAZ002>016-
026.
NH...FLASH FLOOD WATCH THROUGH THURSDAY AFTERNOON FOR NHZ011-012-
015.
RI...FLASH FLOOD WATCH THROUGH THURSDAY AFTERNOON FOR RIZ001>003.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 AM EDT THURSDAY FOR ANZ254>256.
&&
$$
SYNOPSIS...DUNTEN/SIPPRELL
NEAR TERM...DUNTEN/SIPPRELL
SHORT TERM...DUNTEN
LONG TERM...SIPPRELL
AVIATION...DUNTEN/SIPPRELL
MARINE...DUNTEN/SIPPRELL
HYDROLOGY...SIPPRELL
AREA FORECAST DISCUSSION
NWS TAUNTON MA
421 PM EDT TUE JUL 9 2013
.SYNOPSIS...
A FEW SHOWERS AND THUNDERSTORMS WITH LOCALLY HEAVY RAINFALL WILL
AFFECT THE REGION AT TIMES THROUGH FRIDAY. AT THIS POINT...THE
SHOWERS AND THUNDERSTORMS LOOK TO BE MOST WIDESPREAD ON THURSDAY.
MAINLY DRY AND LESS HUMID WEATHER LOOKS FINALLY ARRIVE BY THE
WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
430 PM UPDATE...
UPDATED FORECAST TO ACCOUNT FOR CURRENT TRENDS OTHERWISE
THE FORECAST REMAINS ON TRACK FOR THE LATE AFTERNOON. INTERESTING
SET-UP ACROSS THE REGION THIS AFTERNOON. LINGERING BOUNDARY FROM
YESTERDAYS BACK DOOR COLD FRONT IS STATIONED NORTH OF CQX TO HFD THEN
JETS NORTHWARD ACROSS THE BERKSHIRES. THIS BOUNDARY WILL REMAINS
NEARLY STATIONARY AND WILL CONTINUE TO BE THE FOCUS ON WHERE
CONVECTION WILL CONTINUE. TEMPERATURES NORTH OF THE BOUNDARY ARE
IN THE UPPER 60S TO MID 70S...WHILE SOUTH OF THE BOUNDARY TEMPS
HAVE WARMED INTO THE MID 80S.
20Z RADAR IMAGERY SHOWS SCATTERED SHOWERS AND THUNDER THAT HAS
DEVELOPED ALONG THE BOUNDARY. ALSO SEVERAL OUTFLOW BOUNDARIES FROM
TODAYS THUNDERSTORMS ARE INTERSECTING EVERYWHERE. INTERESTING TO
SEE HOW STORMS WILL EVOLVE LATER THIS AFTERNOON. BELIEVE THAT
THEY WILL CONTINUE TO FIRE ACROSS NH AND ALONG THE CAPE AND SE
MASS WHERE THE BETTER CONVERGENCE IS LOCATED AS WELL AS THE
ENVIRONMENT HAS NOT BEEN WORKED OVER AS MUCH. ML CAPE VALUES ARE
BETWEEN 1000-1500 J/KG ACROSS RHODE ISLAND AND THE CT VALLEY AND
THE BERKSHIRES. SHEAR IS NEARLY NON-EXISTENT SO THESE STORMS WILL
HARDLY MOVE AND WITH PWAT VALUES NEAR 1.7 TO 2 INCHES EXPECT HEAVY
DOWNPOURS WITH THESE CELLS. VERY LOCALIZED FLASH FLOODING IS THE
MAIN CONCERN WITH WIND GUSTS BEING THE SECOND CONCERN. EXPECT
STORMS TO CONTINUE TO FIRE OFF OF THIS BOUNDARY OVER THE NEXT
SEVERAL HOURS. LATEST MESOSCALE MODELS ALSO SUPPORT THIS THEORY AS
THE HRRR SEEMS TO BE DOING A GREAT JOB WITH ONGOING CONVECTION.
TONIGHT...
CURRENT CONVECTION ACROSS THE REGION SHOULD SLOWLY WANE AFTER
SUNSET AS DIURNAL HEATING IS LOST. A FEW SHOWERS MAY CONTINUE TO
LINGER OVERNIGHT BUT THE THREAT FOR STRONG TO SEVERE STORMS WILL
BE LOW. MAIN CONCERN WILL BE THE POTENTIAL FOR LOW CLOUDS AND FOG
AGAIN. BELIEVE THAT BOTH COAST LINES WILL BE AT RISK AS EASTERLY
FLOW IS ACROSS THE EAST COAST AND SOUTHERLY FLOW ONTO THE SOUTH
COAST. THIS WILL KEEP THE MOISTURE STREAMING INTO THE REGION
ALLOWING FOR FOG TO DEVELOP.
OTHERWISE SURFACE LOW WILL MOVE EASTWARD OVERNIGHT PUSHING
THE CURRENT BOUNDARY THAT IS DRAPED ACROSS SE MA/RI AND INTO CT
NORTHWARD AS A WARM FRONT OVERNIGHT AND INTO TOMORROW MORNING.
OVERNIGHT TEMPS WILL BE PLEASANT NORTH OF THE BOUNDARY...IN THE LOW
TO MID 60S. SOUTH OF THE BOUNDARY TEMPS WILL BE IN THE UPPER 60S TO
LOW 70S.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
TOMORROW...
A LOT OF UNCERTAINTY STILL IS IN PLACE FOR TOMORROW. UPPER LEVEL
LOW OVER THE UPPER GREAT LAKES WILL CONTINUE THE TROUGH OVER THE
REGION. QUICK MOVING SHORTWAVE WILL MOVE THROUGH THE FLOW ALLOWING
FROM SOME SORT OF LIFT FOR THE REGION. HOWEVER LOOKING AT FORECAST
GUIDANCE IT SEEMS THE AREA THAT MAY SEE THE BETTER POTENTIAL FOR
STORMS WILL BE OUT WEST ACROSS THE CT VALLEY/ORH HILLS. THIS REGION
WILL HAVE THE BETTER INSTABILITY ONCE THE LOW STRATUS DECK BREAKS
UP.
CURRENT BOUNDARY ACROSS THE REGION NOW WILL LIFT NORTHWARD AS A
FORM OF A WARM FRONT WHEN THE SHORTWAVE APPROACHES. THIS WILL ALLOW
FOR TEMPS TO WARM RIGHT BACK UP INTO THE MID TO UPPER 80S. BELIEVE
THAT STORMS WILL MAINLY BE DIURNALLY DRIVE DURING THE DAY. WITH
LACK OF SHEAR AND FLOW ALOFT BELIEVE THESE STORMS WILL BE NEARLY
STATIONARY AND WITH PWATS IN THE 1.5 TO 2 INCHES...HEAVY DOWNPOURS
WILL BE THE MAIN THREAT. CAPE VALUES SHOULD BE HIGHER THEN TODAY
SO GUSTY WINDS MAY ALSO BE A POTENTIAL ONCE THUNDERSTORMS BEGIN TO
COLLAPSE. STORMS SHOULD BEGIN TO WANE AFTER SUNSET ONCE DIURNAL
HEATING IS LOST.
TOMORROW NIGHT...
AFTER A QUICK LULL IN CONVECTION MODELS ARE INDICATING THAT STORMS
WILL FIRE UP OVERNIGHT AND LAST INTO THE THURSDAY. SYNOPTIC MODELS
ARE STRUGGLING WITH PLACEMENT OF THE COLD FRONT AS THE GFS BRINGS IT
ACROSS SNE FASTER THEN THE GENERAL TREND. ALSO AM HESITANT AS THESE
SORT OF FRONTS HAVE THE TENDENCY TO STALL. HOWEVER IF THE FRONT
MOVES TOWARDS THE REGION LATE TOMORROW NIGHT INTO THURSDAY MORNING
THEN THE OVERNIGHT HOURS MAY BE ACTIVE.
FORECAST GUIDANCE SHOWS ELEVATED INSTABILITY ACROSS THE REGION AS
SHOWALTERS ARE -2C COMBINED WITH DEEP MOISTURE AND A SOURCE OF LIFT
WHICH COULD HAVE STORMS FIRING OVERNIGHT. EXACT COVERAGE AND
PLACEMENT IS STILL UNKNOWN AS THE TIMING IS THE OVERALL QUESTION.
HOWEVER MAIN THREAT APPEARS TO BE HEAVY DOWNPOURS. HAVE CONTEMPLATED
WITH THE ISSUANCE OF A FLASH FLOOD WATCH BUT HAVE COLLABORATION WITH
SURROUND OFFICES DECIDED TO HOLD OFF AS THERE IS STILL A LOT OF
UNCERTAINTY.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
HEADLINES...
* HEAVY RAIN AND POTENTIAL FLOODING FOR THURSDAY
* RAINS LINGER TO THE SOUTHEAST INTO FRIDAY
* A RETURN OF MORE SEASONABLE WEATHER INTO THE WEEKEND AND EARLY WEEK
*/OVERVIEW AND MODEL CONSENSUS...
THOUGH MODELS AGREE UPON A BROAD RIDGING PATTERN EVOLVING ACROSS THE
CONUS...THEY REMAIN AT ODDS AND STRUGGLE WITH HANDLING ENERGY ALONG
THE NORTHERN PERIPHERY OF THE RIDGE. CONSEQUENTIALLY...RUN-TO-RUN
CONSISTENCY HAS BEEN POOR AS OF LATE WITH HANDLING THE EVOLUTION OF
THE MID- TO UPPER-LEVEL ENERGY DIVING SOUTHEAST OUT OF CANADA AND
ACROSS THE NORTHEASTERN CONUS...POTENTIALLY EVOLVING INTO A CLOSED
LOW THAT RETROGRADES SOUTH AND WEST.
HPC/WPC MAINTAINS CONTINUITY WITH THEIR FORECAST...GOING WITH A
09.0Z ENSEMBLE BLEND...NOTING THE UNCERTAIN TRACK OF TROPICAL STORM
CHANTAL. WILL FOLLOW SUIT INCORPORATING THEIR FORECAST INTO A BLEND
OF THE 09.12Z FORECAST GUIDANCE.
*/DAY-TO-DAY DETAILS...
*/THURSDAY INTO THURSDAY NIGHT...
SURFACE COLD FRONT SLOWED ACROSS SOUTHERN NEW ENGLAND AGAINST
RIDGING OF HIGH PRESSURE OVER THE WESTERN ATLANTIC WILL BE FORCED
OFFSHORE DURING THE EVENING HOURS AND OVERNIGHT AS THE MID- TO UPPER-
LEVEL TROUGH AXIS PUSHES SOUTHEAST OUT OF CANADA INTO THE NORTHEAST
CONUS. FEEL 09.12Z GFS IS TOO FAST WITH THIS FEATURE.
CHANCE TO LIKELY POPS WARRANTED THURSDAY WITH DEEP-LAYER FORCING
COUPLED WITH THE RIGHT-ENTRANCE REGION OF THE UPPER-LEVEL JET...
DIMINISHING INTO THE EVENING WITH THE COLD FRONT PUSHING OFFSHORE.
WITH CERTAINTY...COLD POOL WILL PUSH SOUTHEAST IMPROVING MID-LEVEL
LAPSE RATES AS UNI-DIRECTIONAL SOUTHWESTERLY SHEAR INCREASES TO
AROUND 30 KTS ACROSS THE REGION. SO WHILE ELEVATED INSTABILITY IS
PLAUSIBLE...BOUNDARY LAYER DESTABILIZATION IS QUESTIONABLE AS
ACTIVITY COULD BE ONGOING DURING THE MORNING FORCED BY STRONG LOW-
LEVEL CONVERGENCE. CLOUDS IMPEDING DIURNAL HEATING.
LESSER CONFIDENCE OF A SEVERE WEATHER THREAT...GREATER CONCERN FOR
FLOODING WITH 2-INCH PWATS AND AFOREMENTIONED DEEP-LAYER FORCING.
GREATER CHANCE FOR FLOODING ACROSS CENTRAL AND EASTERN PORTIONS OF
SOUTHERN NEW ENGLAND...FOCUSING ON THE MORNING INTO MIDDAY PERIOD.
*/FRIDAY INTO NEXT WEEK...
IT IS NOT ENTIRELY CLEAR HOW THE MID- TO UPPER-LEVEL ENERGY
ASSOCIATED WITH THE ACTIVITY ON THURSDAY WILL EVOLVE. DETERMINISTIC
GFS/ECMWF SOLUTIONS EXHIBIT ATTENDANT ENERGY TO BIFURCATE FROM THE
NORTHERN STREAM...BECOMING A CLOSED LOW AND RETROGRADING SOUTH AND
WEST WITH THE MEAN FLOW AROUND THE BROAD RIDGING ACROSS THE CONUS.
QUITE ODD FOR AN EARLY SUMMERTIME PATTERN.
THAT BEING SAID...SURFACE OUTCOMES REMAIN UNCERTAIN. IT APPEARS HIGH
PRESSURE OUT OF THE GREAT LAKES REGION WILL USHER MORE SEASONABLE
CONDITIONS BACK INTO THE REGION WITH NORTHERLY WINDS...AS A FRONTAL
BOUNDARY REMAINS STALLED OFFSHORE. COULD SEE THE CHANCE OF SHOWERS
FOR FAR SOUTHEAST SOUTHERN NEW ENGLAND INITIALLY. THIS HIGH WILL
TRANSITION EAST RESULTING IN THE RETURN USHERANCE OF SOUTHERLY FLOW
AND PERHAPS RENEWED CHANCES OF SHOWERS AND THUNDERSTORMS AS HEAT AND
HUMIDITY GRADUALLY BUILD BACK OVER THE REGION.
LITTLE FORCING WITHIN THE MID- TO UPPER-LEVELS IS APPARENT...SO ANY
SHOWERS OUTPUTTED BY FORECAST GUIDANCE APPEARS TO BE A RESULT OF
LOCALIZED CONVERGENCE LIKELY ALONG SEA-BREEZE BOUNDARIES /AIR-MASS
THUNDERSTORMS/. CHANCE TO SLIGHT CHANCE POPS ACROSS THE INTERIOR...
LOW CONFIDENCE SEVERE WEATHER THREATS. WILL KEEP CONDITIONS CLOSE TO
SEASONABLE.
&&
.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...TODAY THROUGH WEDNESDAY...
MODERATE CONFIDENCE ON TRENDS...LOW CONFIDENCE ON TIMING.
TODAY...MVFR ACROSS MUCH OF THE REGION WITH IFR ACROSS THE CAPE.
BOUNDARY IS SITUATED GENERALLY FROM KACK-KMMK-KAQW. NORTH AND EAST
OF THE BOUNDARY IS IN EASTERLY TO NORTHEAST FLOW WHILE SOUTH AND
WEST OF THE BOUNDARY IS DUE SOUTH. EXPECT THE CT VALLEY TO BREAK
OUT INTO VFR HOWEVER EVERYWHERE ELSE SHOULD STAY SOCKED IN. VCTS
CONDITIONS ARE BEST FOR PVD/BAF/BDL AS TSRA ARE FIRING ACROSS THE
BOUNDARY.
TONIGHT...MVFR TO IFR CONDITIONS WILL DETERIORATE TO IFR/LIFR
OVERNIGHT. EASTERLY FLOW WILL SOCK THE EAST COAST IN LOW CLOUDS
AND FOG. LIFR CONDITIONS ARE BEST ACROSS THE CAPE.
WEDNESDAY...MAINLY MVFR/VFR CONDITIONS WITH BETTER CHANCE FOR
SHOWERS/TSTMS ESPECIALLY ORH HILLS WESTWARD.
WEDNESDAY NIGHT...MVFR TO IFR CONDITIONS OVERNIGHT AS SHRA AND
TSRA GROW IN COVERAGE OVERNIGHT ESP ACROSS WESTERN TERMINALS.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF TRENDS...LOWER IN TIMING
SPECIFICS.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF TRENDS...LOWER IN
TIMING SPECIFICS. CONTINUED TO MENTION VCTS AS SHOWERS AND TSRA
CONTINUE TO DEVELOP ALONG BOUNDARY.
OUTLOOK...THURSDAY THROUGH SUNDAY...MODERATE CONFIDENCE
THURSDAY INTO THURSDAY NIGHT...
SHRA/TSRA...BETTER CHANCES DURING THE MORNING INTO MIDDAY HOURS
PUSHING NW TO SE. MVFR/IFR CIGS WITH MVFR/IFR VSBYS...CONDITIONS
POTENTIALLY LOWER WITH +RA AND ACROSS SE COASTAL TERMINALS WITH FOG.
SW WINDS BACKING OUT OF THE W/NW WITH COLD FRONTAL PASSAGE.
FRIDAY INTO SUNDAY...
SHRA/TSRA MAY LINGER ACROSS FAR SE COASTAL TERMINALS DURING THE
INITIAL PERIOD WITH MVFR-IFR IMPACTS AT LOWEST. OTHERWISE PREVAILING
VFR WITH NORTHERLY WINDS.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
.SHORT TERM...HIGH CONFIDENCE.
TODAY THROUGH WEDNESDAY...
WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT CRITERIA THROUGH
TOMORROW. AS WINDS SHIFT BACK TO S-SW AND PICK UP DURING WED
AFTERNOON...WITH GUSTS UP TO 20 KT...SEAS MAY BUILD BACK UP TO
AROUND 5 FT ON THE SOUTHERN WATERS. SMALL CRAFT ADV MAY BE NEEDED
THEN. SEEMS THAT WNA GUIDANCE WAS OVERDOING THE SEAS AGAIN SO
HAVE UNDERCUT THEM. EXPECT REDUCED VSBYS TONIGHT INTO TOMORROW
MORNING FROM FOG. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS ON
WED INTO WED NIGHT.
OUTLOOK...THURSDAY INTO SUNDAY...MODERATE CONFIDENCE.
THURSDAY INTO THURSDAY NIGHT...
RAIN AND POSSIBLE THUNDERSTORMS WILL INCREASE TOWARDS THE WATERS
DURING THE DAY AND PREVAIL INTO THE EVENING ALONG AND AHEAD OF AN
APPROACHING COLD FRONT. STORMS MAY BE STRONG WITH GALE FORCE
GUSTS...OTHERWISE PREVAILING SW WINDS AHEAD OF THE COLD FRONT
BACKING OUT OF THE W/NW LATE. SEAS IN EXCESS OF 5 FEET ON THE OUTER
WATERS. VISIBILITY IMPACTS WITH HEAVY RAIN ANTICIPATED.
FRIDAY INTO SUNDAY...
RAIN AND POSSIBLE THUNDERSTORMS WILL LINGER FOR THE INITIAL PERIOD
SLOWLY MOVING INTO THE ATLANTIC. HIGH PRESSURE BUILDING FROM THE
WEST WILL RESULT IN NORTHERLY FLOW. COULD SEE GUSTS UP TO AROUND 20
KTS WHICH WOULD ALLOW SEAS ON THE OUTER WATERS TO REMAIN AT OR ABOVE
5 FEET.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...DUNTEN/SIPPRELL
NEAR TERM...DUNTEN
SHORT TERM...DUNTEN
LONG TERM...SIPPRELL
AVIATION...DUNTEN/SIPPRELL
MARINE...DUNTEN/SIPPRELL
AREA FORECAST DISCUSSION
NWS TAUNTON MA
202 PM EDT TUE JUL 9 2013
.SYNOPSIS...
A FEW SHOWERS AND THUNDERSTORMS WITH LOCALLY HEAVY RAINFALL WILL
AFFECT THE REGION AT TIMES THROUGH FRIDAY. AT THIS POINT...THE
SHOWERS AND THUNDERSTORMS LOOK TO BE MOST WIDESPREAD ON THURSDAY.
MAINLY DRY AND LESS HUMID WEATHER LOOKS FINALLY ARRIVE BY THE
WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
200 PM UPDATE...
UPDATED FORECAST TO ACCOUNT FOR CURRENT TRENDS OTHERWISE GENERALLYFORECAST
REMAINS ON TRACK FOR THIS AFTERNOON. INTERESTING SET-UP ACROSS THE
REGION THIS AFTERNOON. LINGERING BOUNDARY FROM YESTERDAYS BACK
DOOR COLD FRONT IS STATIONED NORTH OF ACK TO MMK THEN JETS
NORTHWARD ACROSS THE BERKSHIRES. THIS BOUNDARY WILL REMAINS
NEARLYSTATIONARYAND WILL BE THE FOCUS ON WHERE CONVECTION WILL
FIRE. TEMPERATURES NORTH OF THE BOUNDARY ARE IN THE UPPER 60S TO
MID 70S...WHILE SOUTH OF THE BOUNDARY TEMPS HAVE WARMED INTO THE
MID 80S.
18Z RADAR IMAGERY SHOWS A GOOD AMOUNT OF STORM COVERAGE THAT HAS
DEVELOPED ALONG THIS BOUNDARY. SATELLITE IMAGERY ALSO SHOWN SOME
CLEARING ALLOWING FOR SOME DIURNAL HEATING. ML CAPE VALUES ARE
BETWEEN 500-1000 J/KG ACROSS RHODE ISLAND AND THE CT VALLEY. SHEAR
IS NEARLY NON-EXISTENT SO THESE STORMS WILL HARDLY MOVE AND WITH
PWAT VALUES NEAR 1.7 TO 2 INCHES EXPECT HEAVY DOWNPOURS WITH THESE
CELLS. VERY LOCALIZED FLASH FLOODING IS THE MAIN CONCERN WITH WIND
GUSTS BEING THE SECOND CONCERN. EXPECT STORMS TO CONTINUE TO FIRE
OFF OF THIS BOUNDARY THROUGHOUT THE AFTERNOON HOURS. LATEST
MESOSCALE MODELS ALSO SUPPORT THIS THEORY AS THE HRRR SEEMS TO BE
DOING A GREAT JOB WITH ONGOING CONVECTION.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
TONIGHT...
WILL SEE LEFTOVER SCT SHOWERS/TSTMS...SOME OF WHICH WILL BE HEAVY
RAINERS...THAT WILL TEND DWINDLE AFTER THE HEATING OF THE DAY.
SOME MAY LINGER WEST OF THE CT RIVER AND THE E SLOPES OF THE
BERKSHIRES AS K INDICES SURGE TO THE MID 30S OVERNIGHT. MAY ALSO
SEE ANOTHER WEAK SHORT WAVE MOVE OUT OF N NEW ENGLAND AFTER
MIDNIGHT...SO MAY RENEW CHANCE FOR PRECIP ACROSS CENTRAL AND
EASTERN AREAS.
WEDNESDAY...
APPEARS THAT THE STALLED FRONT MAY MAKE A RUN N OF THE REGION
DURING THE DAY AS WINDS SHIFT BACK TO S-SW DOWN THE COAST. LOOKS
LIKE ANOTHER WAVE MOVES ALONG THIS FRONT AS WELL. THIS WILL
ENHANCE CHANCES FOR PRECIP AS SURGE OF HIGHER PWATS...ON ORDER OF
AROUND 2 INCHES...WORK NE INTO THE REGION. WITH THE TROPICAL
CONNECTION BACK IN PLACE...WILL SEE ANOTHER ROUND OF SHOWERS/TSTMS
FOR MOST AREAS THROUGH MIDDAY...THEN MAY ACTUALLY SHIFT A BIT TO
THE W DURING THE AFTERNOON. CONTINUED WITH LIKELY POPS FOR SW NH/W
MA/N CENTRAL CT WHERE BEST LIFT/INSTABILITY WILL REMAIN THROUGH
THE DAY. TEMPS WILL ALSO SPIKE UP...EVEN WITH THE PRECIP AROUND...
UPWARDS TO THE MID-UPPER 80S ACROSS THE MID AND LOWER CT VALLEY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
HIGHLIGHTS...
* A ROUND OF SHOWERS/THUNDERSTORMS LIKELY THU WITH HEAVY RAINFALL
* A FEW LEFT OVER SHOWERS/STORMS MAY LINGER INTO FRI
* RELIEF FROM HUMIDITY EXPECTED BY THIS WEEKEND
DETAILS...
WEDNESDAY NIGHT...
THERE IS UNCERTAINTY ON HOW MUCH CONVECTION WILL BE ON GOING IN OUR
REGION WEDNESDAY EVENING. WHILE WE MAY SEE SOME ACROSS OUR INTERIOR
ZONES...THE BETTER FOCUS WILL BE TO THE WEST OF OUR REGION CLOSER TO
THE SHORTWAVE/INSTABILITY AXIS. HOWEVER...WE MAY SEE AN INCREASE IN
SCATTERED SHOWERS/THUNDERSTORMS DURING THE OVERNIGHT HOURS AS LOW
LEVEL JET KICKS IN AHEAD OF THE SHORTWAVE. THE FAR SOUTHEAST NEW
ENGLAND COAST IS OFTEN PRONE TO THIS TYPE OF ELEVATED CONVECTION AND
SOME MODELS SEEM TO BE HINTING AT THIS POTENTIAL. LOCALLY HEAVY
RAINFALL WOULD BE A CONCERN GIVEN HIGH PWATS IN PLACE.
THURSDAY...
UPPER LEVEL SHORTWAVE AND SURFACE TROUGH WILL MOVE
THROUGH THE REGION ON THURSDAY. WE ARE FAIRLY CONFIDENT THAT THIS
SHOULD GENERATE A ROUND OF SHOWERS AND THUNDERSTORMS ACROSS MOST OF
THE REGION. THEREFORE...WILL CARRY LIKELY POPS BUT THERE IS
UNCERTAINTY ON THE EXACT TIMING.
THE MAIN THREAT WILL BE HEAVY RAINFALL AND LOCALIZED FLOODING.
WIDESPREAD SEVERE WEATHER APPEARS UNLIKELY GIVEN A FAIR AMOUNT OF
CLOUD COVER AND LIMITED 0 TO 6 KM SHEAR. HOWEVER...MID LEVEL LAPSE
RATES WILL BE A LITTLE BETTER THAN RECENT DAYS SO A FEW STRONG TO
SEVERE THUNDERSTORMS CAN/T BE RULED OUT. THE BULK OF THE SHOWERS
AND THUNDERSTORMS WILL PROBABLY COME TO AN END DURING THURSDAY
EVENING.
FRIDAY...
APPEARS COLD FRONT WILL HAVE MOVED TO NEAR THE COAST OR
JUST OFF THE COAST BY THIS TIME. HOWEVER...UPPER TROUGH/COLD POOL
ALOFT WILL STILL BE LINGERING TO THE WEST OUR REGION.
THEREFORE...OPTED TO KEEP CHANCE POPS IN THE FORECAST FOR PERHAPS
A FEW MORE SHOWERS AND THUNDERSTORMS BUT NOT EXPECTING THE ENTIRE
DAY TO BE A WASHOUT.
SATURDAY THROUGH MONDAY...
UPPER TROUGH WILL HANG AROUND SOUTHERN NEW
ENGLAND...BUT THERE WILL BE HIGH PRESSURE AT THE SURFACE.
THEREFORE...LEANING TO MAINLY DRY WEATHER WITH SEASONABLE HIGH
TEMPERATURES MAINLY IN THE 80S. WILL HAVE TO WATCH A FEW WEAK WAVES
OF LOW PRESSURE PASSING TO OUR SOUTHEAST. IF THEY COME CLOSER THAN
EXPECTED SOME OF OUR AREA COULD BE GRAZED BY A FEW SHOWERS...BUT FOR
NOW KEEPING THE BULK OF THEM OFF THE COAST.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
.SHORT TERM...TODAY THROUGH WEDNESDAY...
MODERATE CONFIDENCE ON TRENDS...LOW CONFIDENCE ON TIMING.
TODAY...MVFR ACROSS MUCH OF THE REGION WITH IFR ACROSS THE CAPE.
BOUNDARY IS SITUATED GENERALLY FROM KACK-KMMK-KAQW. NORTH AND EAST
OF THE BOUNDARY IS IN EASTERLY TO NORTHEAST FLOW WHILE SOUTH AND
WEST OF THE BOUNDARY IS DUE SOUTH. EXPECT THE CT VALLEY TO BREAK
OUT INTO VFR HOWEVER EVERYWHERE ELSE SHOULD STAY SOCKED IN. VCTS
CONDITIONS ARE BEST FOR PVD/BAF/BDL AS TSRA ARE FIRING ACROSS THE
BOUNDARY.
TONIGHT...MVFR TO IFR CONDITIONS WILL DETERIORATE TO IFR/LIFR
OVERNIGHT. EASTERLY FLOW WILL SOCK THE EAST COAST IN LOW CLOUDS
AND FOG. LIFR CONDITIONS ARE BEST ACROSS THE CAPE.
WEDNESDAY...MAINLY MVFR/VFR CONDITIONS WITH BETTER CHANCE FOR
SHOWERS/TSTMS ESPECIALLY ORH HILLS WESTWARD.
WEDNESDAY NIGHT...MVFR TO IFR CONDITIONS OVERNIGHT AS SHRA AND
TSRA GROW IN COVERAGE OVERNIGHT ESP ACROSS WESTERN TERMINALS.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF TRENDS...LOWER IN TIMING
SPECIFICS.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF TRENDS...LOWER IN
TIMING SPECIFICS. CONTINUED TO MENTION VCTS AS SHOWERS AND TSRA
CONTINUE TO DEVELOP ALONG BOUNDARY.
OUTLOOK...THURSDAY THROUGH SATURDAY...
MODERATE CONFIDENCE.
WEDNESDAY NIGHT AND THURSDAY...LOW CLOUDS/FOG PATCHES WILL LIKELY
RESULT IN SOME MVFR-IFR CONDITIONS ESPECIALLY ON THE SOUTHEAST NEW
ENGLAND COAST. IN ADDITION...LOWER CONDITIONS ARE ALSO EXPECTED IN
SCATTERED SHOWERS AND THUNDERSTORMS WED NIGHT AND THU. ACTIVITY
LOOKS MOST WIDESPREAD ON THURSDAY.
FRIDAY AND SATURDAY...A FEW LINGERING SHOWERS/THUNDERSTORMS POSSIBLE
ON FRIDAY. OTHERWISE...VFR CONDITIONS LIKELY DOMINATE.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
.SHORT TERM...MODERATE TO HIGH CONFIDENCE.
TODAY THROUGH WEDNESDAY...
WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT CRITERIA THROUGH
TONIGHT. AS WINDS SHIFT BACK TO S-SW AND PICK UP DURING WED
AFTERNOON...WITH GUSTS UP TO 20 KT...SEAS MAY BUILD BACK UP TO
AROUND 5 FT ON THE SOUTHERN WATERS. SMALL CRAFTS MAY BE NEEDED
THEN. EXPECT REDUCED VSBYS THROUGH LATE MORNING IN FOG...WITH
REDEVELOPMENT TONIGHT INTO WED MORNING.
THERE IS A LOW PROBABILITY FOR A CHANCE OF SHOWERS/TSTMS
THIS AFTERNOON/EVENING AS WELL.
OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...
MODERATE CONFIDENCE.
WEDNESDAY NIGHT AND THURSDAY...
SOUTHWEST FLOW WILL CONTINUE OUT AHEAD OF A COLD FRONT. INVERSION
OVER THE WATER SHOULD KEEP SEAS A BIT LOWER THAN WNA GUIDANCE
SUGGESTS...BUT STILL MAY SEE SOME 5 FOOT SEAS ACROSS THE SOUTHERN
WATERS AS A RESULT OF THE LONG FETCH. NEAR SHORE WIND GUSTS TO
AROUND 25 KNOTS WILL ALSO BE POSSIBLE THURSDAY AFTERNOON ALONG THE
SOUTH COASTAL WATERS.
TWO OTHER CONCERNS WILL BE FOR AREAS OF DENSE FOG LATE WED NIGHT
INTO THU MORNING ACROSS THE SOUTHERN WATERS. THERE MAY ALSO BE A A
ROUND OR TWO OF THUNDERSTORMS ON THURSDAY.
FRIDAY AND SATURDAY...
HIGH PRESSURE WILL BUILD ACROSS THE WATERS. ANY LINGERING 5 FOOT
SEAS ACROSS THE SOUTHERN WATERS SHOULD DROP BELOW SCA FRIDAY NIGHT.
OTHERWISE...WINDS/SEAS SHOULD DROP BELOW SCA THRESHOLDS.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...FRANK/EVT
NEAR TERM...DUNTEN
SHORT TERM...EVT
LONG TERM...FRANK
AVIATION...FRANK/DUNTEN
MARINE...FRANK/EVT
AREA FORECAST DISCUSSION
NWS NEW YORK NY
152 PM EDT TUE JUL 9 2013
.SYNOPSIS...
A WEAK FRONT ACROSS SOUTHERN CONNECTICUT WILL GRADUALLY RETURN
NORTH THIS AFTERNOON. A WEAK TROUGH APPROACHES WEDNESDAY
AFTERNOON...WITH A SLOWLY MOVING FRONTAL SYSTEM AFFECTING THE
REGION THROUGH THE END OF THE WEEK. A COLD FRONT SLOWLY MOVES
THROUGH THE REGION WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...AND
THEN STALLS OFFSHORE. HIGH PRESSURE THEN TRIES TO BUILD INTO THE
REGION FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
STALLED OUT FRONTAL BOUNDARY ACROSS SOUTHERN CT SERVING AS A
TRIGGER IN AN UNCAPPED AIRMASS. THIS COMBINED WITH A LIGHT WEST
FLOW ALOFT IS RAISING THE FLOOD THREAT POTENTIAL ACROSS THIS AREA.
IN ADDITION...THERE IS SOME ISOLATED CONVECTION POPPING UP ALONG
THE SEABREEZE FRONT ON THE NORTH SHORE OF LI. BOTH AREAS WILL BE
MONITORED FOR FLOODING.
LATEST HRRR MODEL TAKES BOUNDARY SLOWLY NORTH THIS AFTERNOON ALONG
WITH THE CONVECTION. ADDITIONAL SCT CONVECTION WILL LIKELY FIRE UP
WITH AN APPROACHING SHORT WAVE TROF TO THE NORTH AND WEST OF
NYC...BEFORE DISSIPATING NEAR THE COAST EARLY THIS EVE. SEABREEZE
BOUNDARY IS ALSO ANOTHER POTENTIAL TRIGGER FOR CONVECTION. DUE TO
WEAK STEERING WINDS FROM THE WEST AT 10 KT OR LESS...ANY
CONVECTION WILL BE CAPABLE OF BRIEF HEAVY DOWNPOURS. WIND SHEAR IS
WEAK WHICH DOES NOT SUPPORT ORGANIZED SEVERE CONVECTION.
VERY WARM TEMPS CONTINUE WITH DEWPOINTS INCREASING A TAD AS COMPARED
TO YESTERDAY. HEAT INDICES ACROSS NYC METRO AND INTERIOR SHOULD
TOP OUT IN THE LOWER 90S ONCE AGAIN.
A MODERATE RISK FOR RIP CURRENTS EXISTS AT THE ATLANTIC OCEAN
BEACHES OF EASTERN LONG ISLAND TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
WEAK VORTS WILL CONTINUE TO ROTATE THROUGH THE REGION TONIGHT INTO
WEDNESDAY...AS A TROUGH DIGS INTO THE GREAT LAKES. AT THE
SURFACE...THE BACK DOOR FRONT WILL GRADUALLY PUSH NORTH TONIGHT INTO
WEDNESDAY. ON WEDNESDAY...A PRE-FRONTAL TROUGH WILL APPROACH THE
REGION IN THE AFTERNOON AHEAD OF A DEVELOPING LOW PRESSURE SYSTEM
NEAR HUDSON BAY.
MAIN FOCUS FOR ANY SHRA/TSRA TONIGHT SHOULD BE NORTH OF THE REGION
WITH LLJ FORCING AND THE NORTHWARD MOVING FRONTAL BOUNDARY OVERNIGHT.
OTHERWISE...WITH DIMINISHING INSTABILITY THIS EVENING...WOULD
EXPECTED ANY CONVECTION TO GRADUALLY WEAKEN. AN ISOLATED SHRA/TSRA
IS POSSIBLE OVERNIGHT WITH INCREASING LLJ...MARGINAL
INSTABILITY...AND WEAK VORT ACTIVITY...BUT MAINLY DRY. INCREASINGLY
MOIST SOUTHERLY FLOW WILL BRING A POTENTIAL FOR PATCHY FOG AND
STRATUS OVERNIGHT.
POTENTIAL INCREASES FOR MORE WIDESPREAD CONVECTION ACROSS WESTERN
ZONES...BETWEEN APPROACHING PRE-FRONTAL TROUGH AND SEABREEZE
BOUNDARY...WEDNESDAY AFTERNOON WITH STRENGTHENING WIND FIELDS AND
APPROACHING SHORTWAVE. SEVERE POTENTIAL WILL BE PREDICATED BY
AMOUNT OF SUNSHINE...BUT WITH AN INCREASINGLY MOIST AIRMASS A
MODERATELY UNSTABLE AIRMASS IS QUITE POSSIBLE IN THE ABOVE
MENTIONED AREA. THE OTHER THREAT WILL BE FOR HEAVY RAIN AND
POTENTIAL FLASH FLOODING WITH TRAINING CELLS ALONG S/N ORIENTED
BOUNDARIES AS PWATS INCREASE TO AROUND 2" AND WARM CLOUD LAYER
INCREASES.
VERY WARM AND INCREASINGLY HUMID CONDITIONS ON WED...WITH TEMPS IN
THE MID TO UPPER 80S NYC/NJ METRO AND INTERIOR...WITH LOWER TO MID
80S ALONG THE COAST IN SOUTHERLY SYNOPTIC FLOW.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
UNSETTLED WEATHER ON TAP FOR THE MIDDLE TO THE END OF THE WEEK AS
LOW PRES TRACKING ACROSS EASTERN CANADA DRAGS A COLD THROUGH THE
REGION ON THURSDAY. THE FIRST ROUND OF SHOWERS AND POSSIBLE
THUNDERSTORMS WILL TAPER OFF IN THE FIRST HALF OF WEDNESDAY
NIGHT....AND THEN ADDITIONAL SHOWERS AND POSSIBLE THUNDERSTORMS WILL
DEVELOP ON THURSDAY AS WEAK LOW PRES DEVELOPS ALONG THE FRONT AND
SLIDES THROUGH THE REGION. WITH PWATS AROUND 2"...CAN EXPECT HEAVY
RAIN. SCATTERED TO NUMEROUS SHOWERS/TSTMS WILL IMPACT THE REGION
THROUGHOUT THE DAY...TAPERING OFF LATE.
BASED ON THE MODEST SW FLOW AND BUILDING SEAS...DANGEROUS RIPS
APPEAR LIKELY WED AND THU AT THE OCEAN.
COLD FRONT WILL BE THROUGH THE REGION THURSDAY NIGHT AND BECOMES
NEARLY STATIONARY EAST OF THE AREA. H5 TROUGH/SHORTWAVE MOVES RIGHT
OVER THE AREA ON FRIDAY AND THEN STALLS OUT OVER THE AREA. EVEN
THOUGH HIGH PRES BUILDS IN AT THE SFC...WILL HAVE TO KEEP AT LEAST
CHANCE POPS IN THE FORECAST FOR THE WEEKEND DUE TO THIS UPPER LEVEL
SYSTEM OVER THE AREA.
RETURN FLOW SETS UP BRINGING AN INCREASE IN THE HEAT AND HUMIDITY
AGAIN ON MON.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
VFR FORECAST INTO THIS EVENING FOR ALL SITES EXCEPT KGON.
CONVECTION DEVELOPING...ISOLATED TO SCATTERED CONVECTION IS
WILL PERSIST THIS AFTERNOON THROUGH 12Z WEDNESDAY...BUT
CONFIDENCE IN EXACT TIMING/LOCATION NOT HIGH ENOUGH TO INCLUDE IN
TAFS. VSBYS MAY DROP TO MVFR AFTER MIDNIGHT /LOW
CONFIDENCE/...THEN LIFT AROUND 13Z WEDNESDAY. FIRST NIGHT OF
SOUTHERLY FLOW /AS OPPOSED TO SOUTHWESTERLY/...SO MVFR CIGS ARE NOT
EXPECTED...BUT WILL MONITOR TRENDS. EXCEPTION IS AT KGON WHERE IFR
CIGS/VSBYS ARE FORECAST BETWEEN 09 AND 14Z WEDNESDAY...WITH MVFR
CIGS/VSBYS FORECAST ON EITHER SIDE OF THAT. OCCASIONAL LIFR
POSSIBLE AT KGON AROUND 12Z...BUT LOW CONFIDENCE.
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)
KEWR FCSTER COMMENTS: BEST CHANCE OF TSTMS AFTER 20Z. ANY TSTMS
NEAR TERMINAL COULD CAUSE WINDS TO GO VRB BRIEFLY.
KJFK FCSTER COMMENTS: BEST CHANCE OF TSTMS AFTER 20Z. ANY TSTMS
NEAR TERMINAL COULD CAUSE WINDS TO GO VRB BRIEFLY.
KLGA FCSTER COMMENTS: BEST CHANCE OF TSTMS AFTER 20Z. ANY TSTMS
NEAR TERMINAL COULD CAUSE WINDS TO GO VRB BRIEFLY.
KTEB FCSTER COMMENTS: BEST CHANCE OF TSTMS AFTER 20Z. ANY TSTMS
NEAR TERMINAL COULD CAUSE WINDS TO GO VRB BRIEFLY.
KHPN FCSTER COMMENTS: BEST CHANCE OF TSTMS AFTER 20Z. ANY TSTMS
NEAR TERMINAL COULD CAUSE WINDS TO GO VRB BRIEFLY.
KISP FCSTER COMMENTS: CONVECTION THROUGH 19Z. ADDITIONAL TSTMS
POSSIBLE AFTER 19Z. ANY TSTMS NEAR TERMINAL COULD CAUSE WINDS TO
GO VRB BRIEFLY.
.OUTLOOK FOR 18Z WEDNESDAY THROUGH SUN...
.THU-FRI...SUB VFR FOG/CIGS POSSIBLE DAILY 06Z-14Z. SCT TSTMS
POSSIBLE DAILY MAINLY 18Z-04Z WITH SUB VFR POSSIBLE AT TIMES.
.SAT...SUB VFR POSSIBLE IN SHOWERS.
.SUN...VFR.
&&
.MARINE...
SUB SCA CONDS THROUGH TONIGHT WITH GENERAL SW WINDS EXPECTED.
WINDS ARE EXPECTED TO GRADUALLY INCREASE ON WEDNESDAY AHEAD OF AN
APPROACHING PRE-FRONTAL TROUGH. THERE IS POTENTIAL FOR MARGINAL
SCA WINDS ACROSS WESTERN OCEAN WATERS INTO ENTRANCE OF NYC HARBOR
LATE WED WITH COASTAL JET.
SOUTHERLY FLOW INCREASES ON WEDNESDAY AHEAD OF A SLOWLY MOVING COLD
FRONT. THIS WILL BUILD SEAS ON THE OCEAN TO SCA LEVELS BY WEDNESDAY
NIGHT...AND SCA CONDITIONS WILL CONTINUE THROUGH THURSDAY. OUTSIDE
OF THE S SHORE BAYS...WHERE WINDS MAY REACH SCA LEVELS...THE
REMAINING WATERS SHOULD REMAIN BELOW SCA LEVELS. HIGH PRES THEN
BUILDS NORTH OF THE WATERS FRIDAY THROUGH THE WEEKEND. CONDITIONS
ARE THEREFORE EXPECTED TO REMAIN BELOW SCA LEVELS.
&&
.HYDROLOGY...
SCATTERED SHOWERS/THUNDERSTORMS WILL PRODUCE LOCALLY HEAVY RAIN
THIS AFTERNOON. AN ISOLATED FLASH FLOOD THREAT EXISTS WITH ANY
TRAINING CONVECTION...MAINLY ALONG THE WESTERN SEABREEZE BOUNDARY
AND/OR BACKDOOR COLD FRONT.
THE FLASH FLOOD THREAT SHOULD INCREASE A BIT ON WEDNESDAY
AFTERNOON ACROSS WESTERN PORTIONS OF THE AREA...AS HEAVY RAIN
ENVIRONMENT BECOMES INCREASINGLY FAVORABLE AND CONVECTIVE COVERAGE
IS EXPECTED TO INCREASE BETWEEN AN APPROACHING PRE-FRONTAL TROUGH
AND SEABREEZE BOUNDARY. THE THREAT FOR FLASH FLOODING WILL EXIST
IN THE PATH OF ANY TRAINING THUNDERSTORMS.
THUNDERSTORMS WILL BE CAPABLE OF PRODUCING LOCALLY HEAVY RAINFALL
WEDNESDAY THROUGH THURSDAY NIGHT ACROSS THE HSA. ALTHOUGH WIDESPREAD
FLOODING IS NOT EXPECTED AT THIS TIME...FLASH FLOODING IS POSSIBLE
WITH ANY TRAINING CONVECTION.
RAINFALL IN EXCESS OF 2 INCHES IS POSSIBLE IN AN AREA IF
THUNDERSTORMS TRAIN OVER THAT AREA FOR AN HOUR.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
AREA FORECAST DISCUSSION...CORRECTED
NWS NEW YORK NY
1100 AM EDT TUE JUL 9 2013
.SYNOPSIS...
A WEAK FRONT ACROSS SOUTHERN CONNECTICUT WILL GRADUALLY RETURN
NORTH THIS AFTERNOON. A WEAK TROUGH APPROACHES WEDNESDAY
AFTERNOON...WITH A SLOWLY MOVING FRONTAL SYSTEM AFFECTING THE
REGION THROUGH THE END OF THE WEEK. A COLD FRONT SLOWLY MOVES
THROUGH THE REGION WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...AND
THEN STALLS OFFSHORE. HIGH PRESSURE THEN TRIES TO BUILD INTO THE
REGION FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
BASED ON LATEST RADAR IMAGERY AND OBS...A WEAK...DIFFUSE COLD FRONT
APPEARS TO HAVE PUSHED ACROSS SRN CT...WITH LOCAL SEA- AND SOUND-
BREEZES MAKING IT DIFFICULT TO PINPOINT THE EXACT LOCATION.
LATEST HRRR MODEL TAKES BOUNDARY SLOWLY NORTH THIS AFTERNOON WITH
CONVECTION BEING INITIATED ACROSS INTERIOR CT. ADDITIONAL SCT
CONVECTION WILL LIKELY FIRE UP WITH AN APPROACHING SHORT WAVE TROF
TO THE NORTH AND WEST OF NYC...BEFORE DISSIPATING NEAR THE COAST
EARLY THIS EVE. SEABREEZE BOUNDARY IS ALSO ANOTHER POTENTIAL
TRIGGER FOR CONVECTION. DUE TO WEAK STEERING WINDS FROM THE WEST
AT 10 KT OR LESS...ANY CONVECTION WILL BE CAPABLE OF BRIEF HEAVY
DOWNPOURS. WIND SHEAR IS WEAK WHICH DOES NOT SUPPORT ORGANIZED
SEVERE CONVECTION.
VERY WARM TEMPS CONTINUE WITH DEWPOINTS INCREASING A TAD AS COMPARED
TO YESTERDAY. HEAT INDICES ACROSS NYC METRO AND INTERIOR SHOULD
TOP OUT IN THE LOWER 90S ONCE AGAIN.
A MODERATE RISK FOR RIP CURRENTS EXISTS AT THE ATLANTIC OCEAN
BEACHES OF EASTERN LONG ISLAND TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
WEAK VORTS WILL CONTINUE TO ROTATE THROUGH THE REGION TONIGHT INTO
WEDNESDAY...AS A TROUGH DIGS INTO THE GREAT LAKES. AT THE
SURFACE...THE BACK DOOR FRONT WILL GRADUALLY PUSH NORTH TONIGHT INTO
WEDNESDAY. ON WEDNESDAY...A PRE-FRONTAL TROUGH WILL APPROACH THE
REGION IN THE AFTERNOON AHEAD OF A DEVELOPING LOW PRESSURE SYSTEM
NEAR HUDSON BAY.
MAIN FOCUS FOR ANY SHRA/TSRA TONIGHT SHOULD BE NORTH OF THE REGION
WITH LLJ FORCING AND THE NORTHWARD MOVING FRONTAL BOUNDARY OVERNIGHT.
OTHERWISE...WITH DIMINISHING INSTABILITY THIS EVENING...WOULD
EXPECTED ANY CONVECTION TO GRADUALLY WEAKEN. AN ISOLATED SHRA/TSRA
IS POSSIBLE OVERNIGHT WITH INCREASING LLJ...MARGINAL
INSTABILITY...AND WEAK VORT ACTIVITY...BUT MAINLY DRY. INCREASINGLY
MOIST SOUTHERLY FLOW WILL BRING A POTENTIAL FOR PATCHY FOG AND
STRATUS OVERNIGHT.
POTENTIAL INCREASES FOR MORE WIDESPREAD CONVECTION ACROSS WESTERN
ZONES...BETWEEN APPROACHING PRE-FRONTAL TROUGH AND SEABREEZE
BOUNDARY...WEDNESDAY AFTERNOON WITH STRENGTHENING WIND FIELDS AND
APPROACHING SHORTWAVE. SEVERE POTENTIAL WILL BE PREDICATED BY
AMOUNT OF SUNSHINE...BUT WITH AN INCREASINGLY MOIST AIRMASS A
MODERATELY UNSTABLE AIRMASS IS QUITE POSSIBLE IN THE ABOVE
MENTIONED AREA. THE OTHER THREAT WILL BE FOR HEAVY RAIN AND
POTENTIAL FLASH FLOODING WITH TRAINING CELLS ALONG S/N ORIENTED
BOUNDARIES AS PWATS INCREASE TO AROUND 2" AND WARM CLOUD LAYER
INCREASES.
VERY WARM AND INCREASINGLY HUMID CONDITIONS ON WED...WITH TEMPS IN
THE MID TO UPPER 80S NYC/NJ METRO AND INTERIOR...WITH LOWER TO MID
80S ALONG THE COAST IN SOUTHERLY SYNOPTIC FLOW.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
UNSETTLED WEATHER ON TAP FOR THE MIDDLE TO THE END OF THE WEEK AS
LOW PRES TRACKING ACROSS EASTERN CANADA DRAGS A COLD THROUGH THE
REGION ON THURSDAY. THE FIRST ROUND OF SHOWERS AND POSSIBLE
THUNDERSTORMS WILL TAPER OFF IN THE FIRST HALF OF WEDNESDAY
NIGHT....AND THEN ADDITIONAL SHOWERS AND POSSIBLE THUNDERSTORMS WILL
DEVELOP ON THURSDAY AS WEAK LOW PRES DEVELOPS ALONG THE FRONT AND
SLIDES THROUGH THE REGION. WITH PWATS AROUND 2"...CAN EXPECT HEAVY
RAIN. SCATTERED TO NUMEROUS SHOWERS/TSTMS WILL IMPACT THE REGION
THROUGHOUT THE DAY...TAPERING OFF LATE.
BASED ON THE MODEST SW FLOW AND BUILDING SEAS...DANGEROUS RIPS
APPEAR LIKELY WED AND THU AT THE OCEAN.
COLD FRONT WILL BE THROUGH THE REGION THURSDAY NIGHT AND BECOMES
NEARLY STATIONARY EAST OF THE AREA. H5 TROUGH/SHORTWAVE MOVES RIGHT
OVER THE AREA ON FRIDAY AND THEN STALLS OUT OVER THE AREA. EVEN
THOUGH HIGH PRES BUILDS IN AT THE SFC...WILL HAVE TO KEEP AT LEAST
CHANCE POPS IN THE FORECAST FOR THE WEEKEND DUE TO THIS UPPER LEVEL
SYSTEM OVER THE AREA.
RETURN FLOW SETS UP BRINGING AN INCREASE IN THE HEAT AND HUMIDITY
AGAIN ON MON.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
A TROUGH OF LOW PRESSURE WILL REMAIN OVER THE LOCAL AREA THROUGH
TODAY.
CONDITIONS WILL REMAIN PRIMARILY VFR TODAY. ONE EXCEPTION IS AT KGON
WHERE A WEAK COLD FRONT HAS PUSHED SOUTH AND BROUGHT IFR CIGS. THESE
CIGS HAVE BEGUN TO LIFT BUT MVFR/IFR AT TIMES IS STILL ANTICIPATED
THROUGH THE AFTERNOON.
WINDS WILL BE LIGHT AND MAY VARY TO E/ENE DIRECTION AT
KGON/KLGA THROUGH EARLY AFTERNOON. OTHERWISE...LIGHT SW WINDS
INCREASE TO 10 AND 15 KT AFTER 18Z. EARLY AFTERNOON SEA BREEZES
ARE EXPECTED.
SHOWERS AND TSTORMS ARE POSSIBLE TODAY...BUT CONFIDENCE TOO LOW IN
TIMING AND PLACEMENT TO INCLUDE IN TAFS.
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)
KEWR FCSTER COMMENTS: BEST CHANCE FOR SHOWERS/TSTORMS WILL BE AFTER
18Z.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KJFK FCSTER COMMENTS: TIMING OF SEA BREEZE COULD BE OFF BY +/-
AN HOUR. BEST CHANCE FOR SHOWERS/TSTORMS WILL BE AFTER 18Z.
KLGA FCSTER COMMENTS: VRB WINDS THROUGH EARLY AFTN ALONG
STALLED BOUNDARY. TIMING OF WIND SHIFT/SEA BREEZE COULD BE OFF BY
+/- AN HOUR OR TWO EARLY THIS AFTN. BEST CHC FOR
SHOWERS/TSTMS WILL BE AFTER 17Z.
KTEB FCSTER COMMENTS: BEST CHANCE FOR SHOWERS/TSTORMS WILL BE AFTER
18Z.
KHPN FCSTER COMMENTS: BEST CHANCE FOR SHOWERS/TSTORMS WILL BE AFTER
18Z.
KISP FCSTER COMMENTS: TIMING OF SEA BREEZE COULD BE OFF BY +/- AN
HOUR.
.OUTLOOK FOR 15Z WEDNESDAY THROUGH SAT...
.WED-FRI...MVFR FOG/CIGS POSSIBLE DAILY 06Z-14Z. SCT TSTMS POSSIBLE
DAILY MAINLY 18Z-04Z WITH MVFR CIGS AND IFR VSBY IN HVY RAIN AND
GUSTY WINDS. OTHERWISE...MAINLY VFR.
.SAT...MAINLY VFR. MVFR POSSIBLE IN SHOWERS.
&&
.MARINE...
SUB SCA CONDS THROUGH TONIGHT WITH GENERAL SW WINDS EXPECTED.
WINDS ARE EXPECTED TO GRADUALLY INCREASE ON WEDNESDAY AHEAD OF AN
APPROACHING PRE-FRONTAL TROUGH. THERE IS POTENTIAL FOR MARGINAL
SCA WINDS ACROSS WESTERN OCEAN WATERS INTO ENTRANCE OF NYC HARBOR
LATE WED WITH COASTAL JET.
SOUTHERLY FLOW INCREASES ON WEDNESDAY AHEAD OF A SLOWLY MOVING COLD
FRONT. THIS WILL BUILD SEAS ON THE OCEAN TO SCA LEVELS BY WEDNESDAY
NIGHT...AND SCA CONDITIONS WILL CONTINUE THROUGH THURSDAY. OUTSIDE
OF THE S SHORE BAYS...WHERE WINDS MAY REACH SCA LEVELS...THE
REMAINING WATERS SHOULD REMAIN BELOW SCA LEVELS. HIGH PRES THEN
BUILDS NORTH OF THE WATERS FRIDAY THROUGH THE WEEKEND. CONDITIONS
ARE THEREFORE EXPECTED TO REMAIN BELOW SCA LEVELS.
&&
.HYDROLOGY...
SCATTERED SHOWERS/THUNDERSTORMS WILL PRODUCE LOCALLY HEAVY RAIN
THIS AFTERNOON. AN ISOLATED FLASH FLOOD THREAT EXISTS WITH ANY
TRAINING CONVECTION...MAINLY ALONG THE WESTERN SEABREEZE BOUNDARY
AND/OR BACKDOOR COLD FRONT.
THE FLASH FLOOD THREAT SHOULD INCREASE A BIT ON WEDNESDAY
AFTERNOON ACROSS WESTERN PORTIONS OF THE AREA...AS HEAVY RAIN
ENVIRONMENT BECOMES INCREASINGLY FAVORABLE AND CONVECTIVE COVERAGE
IS EXPECTED TO INCREASE BETWEEN AN APPROACHING PRE-FRONTAL TROUGH
AND SEABREEZE BOUNDARY. THE THREAT FOR FLASH FLOODING WILL EXIST
IN THE PATH OF ANY TRAINING THUNDERSTORMS.
THUNDERSTORMS WILL BE CAPABLE OF PRODUCING LOCALLY HEAVY RAINFALL
WEDNESDAY THROUGH THURSDAY NIGHT ACROSS THE HSA. ALTHOUGH WIDESPREAD
FLOODING IS NOT EXPECTED AT THIS TIME...FLASH FLOODING IS POSSIBLE
WITH ANY TRAINING CONVECTION.
RAINFALL IN EXCESS OF 2 INCHES IS POSSIBLE IN AN AREA IF
THUNDERSTORMS TRAIN OVER THAT AREA FOR AN HOUR.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MPS/NV
NEAR TERM...NV/DW
SHORT TERM...NV
LONG TERM...MPS
AVIATION...BC
MARINE...MPS/NV
HYDROLOGY...MPS/NV
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1059 AM EDT TUE JUL 9 2013
.SYNOPSIS...
A WEAK FRONT ACROSS SOUTHERN CONNECTICUT WILL GRADUALLY RETURN
NORTH THIS AFTERNOON. A WEAK TROUGH APPROACHES WEDNESDAY
AFTERNOON...WITH A SLOWLY MOVING FRONTAL SYSTEM AFFECTING THE
REGION THROUGH THE END OF THE WEEK. A COLD FRONT SLOWLY MOVES
THROUGH THE REGION WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...AND
THEN STALLS OFFSHORE. HIGH PRESSURE THEN TRIES TO BUILD INTO THE
REGION FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
BASED ON LATEST RADAR IMAGERY AND OBS...A WEAK...DIFFUSE COLD FRONT
APPEARS TO HAVE PUSHED ACROSS SRN CT...WITH LOCAL SEA- AND SOUND-
BREEZES MAKING IT DIFFICULT TO PINPOINT THE EXACT LOCATION.
LATEST HRRR MODEL TAKES BOUNDARY SLOWLY NORTH THIS AFTERNOON WITH
CONVECTION BEING INITIATED ACROSS INTERIOR CT. ADDITIONAL SCT
CONVECTION WILL LIKELY FIRE UP WITH AN APPROACHING SHORT WAVE TROF
TO THE NORTH AND WEST OF NYC...BEFORE DISSIPATING NEAR THE COAST
EARLY THIS EVE. SEABREEZE BOUNDARY IS ALSO ANOTHER POTENTIAL
TRIGGER FOR CONVECTION. DUE TO WEAK STEERING WINDS FROM THE WEST
AT 10 KT OR LESS...ANY CONVECTION WILL BE CAPABLE OF BRIEF HEAVY
DOWNPOURS. WIND SHEAR IS WEAK WHICH DOES NOT SUPPORT ORGANIZED
SEVERE CONVECTION.
VERY WARM TEMPS CONTINUE WITH DEWPOINTS INCREASING A TAD AS COMPARED
TO YESTERDAY. HEAT INDICES ACROSS NYC METRO AND INTERIOR SHOULD
TOP OUT IN THE LOWER 90S ONCE AGAIN.
A MODERATE RISK FOR RIP CURRENTS EXISTS AT THE ATLANTIC OCEAN
BEACHES OF EASTERN LONG ISLAND TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
WEAK VORTS WILL CONTINUE TO ROTATE THROUGH THE REGION TONIGHT INTO
WEDNESDAY...AS A TROUGH DIGS INTO THE GREAT LAKES. AT THE
SURFACE...THE BACK DOOR FRONT WILL GRADUALLY PUSH NORTH TONIGHT INTO
WEDNESDAY. ON WEDNESDAY...A PRE-FRONTAL TROUGH WILL APPROACH THE
REGION IN THE AFTERNOON AHEAD OF A DEVELOPING LOW PRESSURE SYSTEM
NEAR HUDSON BAY.
MAIN FOCUS FOR ANY SHRA/TSRA TONIGHT SHOULD BE NORTH OF THE REGION
WITH LLJ FORCING AND THE NORTHWARD MOVING FRONTAL BOUNDARY OVERNIGHT.
OTHERWISE...WITH DIMINISHING INSTABILITY THIS EVENING...WOULD
EXPECTED ANY CONVECTION TO GRADUALLY WEAKEN. AN ISOLATED SHRA/TSRA
IS POSSIBLE OVERNIGHT WITH INCREASING LLJ...MARGINAL
INSTABILITY...AND WEAK VORT ACTIVITY...BUT MAINLY DRY. INCREASINGLY
MOIST SOUTHERLY FLOW WILL BRIG POTENTIAL FOR PATCHY FOG AND STRATUS
OVERNIGHT.
POTENTIAL INCREASES FOR MORE WIDESPREAD CONVECTION ACROSS WESTERN
ZONES...BETWEEN APPROACHING PRE-FRONTAL TROUGH AND SEABREEZE
BOUNDARY...WEDNESDAY AFTERNOON WITH STRENGTHENING WIND FIELDS AND
APPROACHING SHORTWAVE. SEVERE POTENTIAL WILL BE PREDICATED BY
AMOUNT OF SUNSHINE...BUT WITH AN INCREASINGLY MOIST AIRMASS A
MODERATELY UNSTABLE AIRMASS IS QUITE POSSIBLE IN THE ABOVE
MENTIONED AREA. THE OTHER THREAT WILL BE FOR HEAVY RAIN AND
POTENTIAL FLASH FLOODING WITH TRAINING CELLS ALONG S/N ORIENTED
BOUNDARIES AS PWATS INCREASE TO AROUND 2" AND WARM CLOUD LAYER
INCREASES.
VERY WARM AND INCREASINGLY HUMID CONDITIONS ON WED...WITH TEMPS IN
THE MID TO UPPER 80S NYC/NJ METRO AND INTERIOR...WITH LOWER TO MID
80S ALONG THE COAST IN SOUTHERLY SYNOPTIC FLOW.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
UNSETTLED WEATHER ON TAP FOR THE MIDDLE TO THE END OF THE WEEK AS
LOW PRES TRACKING ACROSS EASTERN CANADA DRAGS A COLD THROUGH THE
REGION ON THURSDAY. THE FIRST ROUND OF SHOWERS AND POSSIBLE
THUNDERSTORMS WILL TAPER OFF IN THE FIRST HALF OF WEDNESDAY
NIGHT....AND THEN ADDITIONAL SHOWERS AND POSSIBLE THUNDERSTORMS WILL
DEVELOP ON THURSDAY AS WEAK LOW PRES DEVELOPS ALONG THE FRONT AND
SLIDES THROUGH THE REGION. WITH PWATS AROUND 2"...CAN EXPECT HEAVY
RAIN. SCATTERED TO NUMEROUS SHOWERS/TSTMS WILL IMPACT THE REGION
THROUGHOUT THE DAY...TAPERING OFF LATE.
BASED ON THE MODEST SW FLOW AND BUILDING SEAS...DANGEROUS RIPS
APPEAR LIKELY WED AND THU AT THE OCEAN.
COLD FRONT WILL BE THROUGH THE REGION THURSDAY NIGHT AND BECOMES
NEARLY STATIONARY EAST OF THE AREA. H5 TROUGH/SHORTWAVE MOVES RIGHT
OVER THE AREA ON FRIDAY AND THEN STALLS OUT OVER THE AREA. EVEN
THOUGH HIGH PRES BUILDS IN AT THE SFC...WILL HAVE TO KEEP AT LEAST
CHANCE POPS IN THE FORECAST FOR THE WEEKEND DUE TO THIS UPPER LEVEL
SYSTEM OVER THE AREA.
RETURN FLOW SETS UP BRINGING AN INCREASE IN THE HEAT AND HUMIDITY
AGAIN ON MON.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
A TROUGH OF LOW PRESSURE WILL REMAIN OVER THE LOCAL AREA THROUGH
TODAY.
CONDITIONS WILL REMAIN PRIMARILY VFR TODAY. ONE EXCEPTION IS AT KGON
WHERE A WEAK COLD FRONT HAS PUSHED SOUTH AND BROUGHT IFR CIGS. THESE
CIGS HAVE BEGUN TO LIFT BUT MVFR/IFR AT TIMES IS STILL ANTICIPATED
THROUGH THE AFTERNOON.
WINDS WILL BE LIGHT AND MAY VARY TO E/ENE DIRECTION AT
KGON/KBDR/KLGA/KISP THROUGH EARLY AFTERNOON. OTHERWISE...LIGHT SW
WINDS INCREASE TO 10 AND 15 KT AFTER 18Z. EARLY AFTERNOON SEA
BREEZES ARE EXPECTED.
SHOWERS AND TSTORMS ARE POSSIBLE TODAY...BUT CONFIDENCE TOO LOW IN
TIMING AND PLACEMENT TO INCLUDE IN TAFS.
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)
KEWR FCSTER COMMENTS: BEST CHANCE FOR SHOWERS/TSTORMS WILL BE AFTER
18Z.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KJFK FCSTER COMMENTS: TIMING OF SEA BREEZE COULD BE OFF BY +/-
AN HOUR. BEST CHANCE FOR SHOWERS/TSTORMS WILL BE AFTER 18Z.
KLGA FCSTER COMMENTS: VRB WINDS THROUGH EARLY AFTN ALONG
STALLED BOUNDARY. TIMING OF WIND SHIFT/SEA BREEZE COULD BE OFF BY
+/- AN HOUR OR TWO EARLY THIS AFTN. BEST CHC FOR
SHOWERS/TSTMS WILL BE AFTER 17Z.
KTEB FCSTER COMMENTS: BEST CHANCE FOR SHOWERS/TSTORMS WILL BE AFTER
18Z.
KHPN FCSTER COMMENTS: BEST CHANCE FOR SHOWERS/TSTORMS WILL BE AFTER
18Z.
KISP FCSTER COMMENTS: TIMING OF SEA BREEZE COULD BE OFF BY +/- AN
HOUR.
.OUTLOOK FOR 15Z WEDNESDAY THROUGH SAT...
.WED-FRI...MVFR FOG/CIGS POSSIBLE DAILY 06Z-14Z. SCT TSTMS POSSIBLE
DAILY MAINLY 18Z-04Z WITH MVFR CIGS AND IFR VSBY IN HVY RAIN AND
GUSTY WINDS. OTHERWISE...MAINLY VFR.
.SAT...MAINLY VFR. MVFR POSSIBLE IN SHOWERS.
&&
.MARINE...
SUB SCA CONDS THROUGH TONIGHT WITH GENERAL SW WINDS EXPECTED.
WINDS ARE EXPECTED TO GRADUALLY INCREASE ON WEDNESDAY AHEAD OF AN
APPROACHING PRE-FRONTAL TROUGH. THERE IS POTENTIAL FOR MARGINAL
SCA WINDS ACROSS WESTERN OCEAN WATERS INTO ENTRANCE OF NYC HARBOR
LATE WED WITH COASTAL JET.
SOUTHERLY FLOW INCREASES ON WEDNESDAY AHEAD OF A SLOWLY MOVING COLD
FRONT. THIS WILL BUILD SEAS ON THE OCEAN TO SCA LEVELS BY WEDNESDAY
NIGHT...AND SCA CONDITIONS WILL CONTINUE THROUGH THURSDAY. OUTSIDE
OF THE S SHORE BAYS...WHERE WINDS MAY REACH SCA LEVELS...THE
REMAINING WATERS SHOULD REMAIN BELOW SCA LEVELS. HIGH PRES THEN
BUILDS NORTH OF THE WATERS FRIDAY THROUGH THE WEEKEND. CONDITIONS
ARE THEREFORE EXPECTED TO REMAIN BELOW SCA LEVELS.
&&
.HYDROLOGY...
SCATTERED SHOWERS/THUNDERSTORMS WILL PRODUCE LOCALLY HEAVY RAIN
THIS AFTERNOON. AN ISOLATED FLASH FLOOD THREAT EXISTS WITH ANY
TRAINING CONVECTION...MAINLY ALONG THE WESTERN SEABREEZE BOUNDARY
AND/OR BACKDOOR COLD FRONT.
THE FLASH FLOOD THREAT SHOULD INCREASE A BIT ON WEDNESDAY
AFTERNOON ACROSS WESTERN PORTIONS OF THE AREA...AS HEAVY RAIN
ENVIRONMENT BECOMES INCREASINGLY FAVORABLE AND CONVECTIVE COVERAGE
IS EXPECTED TO INCREASE BETWEEN AN APPROACHING PRE-FRONTAL TROUGH
AND SEABREEZE BOUNDARY. THE THREAT FOR FLASH FLOODING WILL EXIST
IN THE PATH OF ANY TRAINING THUNDERSTORMS.
THUNDERSTORMS WILL BE CAPABLE OF PRODUCING LOCALLY HEAVY RAINFALL
WEDNESDAY THROUGH THURSDAY NIGHT ACROSS THE HSA. ALTHOUGH WIDESPREAD
FLOODING IS NOT EXPECTED AT THIS TIME...FLASH FLOODING IS POSSIBLE
WITH ANY TRAINING CONVECTION.
RAINFALL IN EXCESS OF 2 INCHES IS POSSIBLE IN AN AREA IF
THUNDERSTORMS TRAIN OVER THAT AREA FOR AN HOUR.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MPS/NV
NEAR TERM...NV/DW
SHORT TERM...NV
LONG TERM...MPS
AVIATION...BC
MARINE...MPS/NV
HYDROLOGY...MPS/NV
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
929 PM EDT Wed Jul 10 2013
.NEAR TERM [Through Rest of Tonight]...
The large scale longwave pattern is highlighted by an elongated
ridge over west half of Conus, broad troughing from NE Canada to TN
valley, weak H5 trough extending over S/Cntrl G, and a weakening
TUTT/upper low migrating Wwd over S/FL and FL Straits with a band of
drier air rotating into SE portions of forecast area. This leaves a
weakness over NE Gulf of Mex region allowing plume of moisture to
advect NE from Gulf to across much of the rest of our area. At lower
levels, broad ridge extending from N/Cntrl Gulf to N FL Newd to
GA/SC Coast. This places much of local area in convergence zone and
warm sector. Weak gradient allowed Gulf seabreeze to migrate inland.
All this allowed storms with locally heavy rains to develop
through the afternoon into early evening.
The precipitation will continue to persist but wane with the continued
loss of heating into late evening especially west of the
Apalachicola River. Passing shortwave approaching from the WNW
around sunrise will stimulate convection across Gulf waters and
adjacent coasts of mainly western most areas. With type 4
seabreeze we should produce at least some landbreeze late to
enhance coastal convection but since much of this area will be
worked over between now and sunrise, not expecting severe wx.
Leftover vortlobe influence from decaying TUTT should remain to
our south and may even push drier air/NVA Nwwd towards our SE
counties. All this reflected in local HRRR and WRF and in model
soundings. i.e. RAP13 at 12z Thurs with between 2.02 and 2.17
inches PWATs at Panama City, Tallahassee and at Cross City. Will
increase POPs especially wrn waters and adjacent coasts and
09-12z. Updated 1st period, to increase POPs NW half to 40-50%
mainly 00Z-02Z then 20-50% E-W 06z-12Z but mainly 10z-12z. Expect
lows in the low to mid 70s.
&&
.SHORT TERM [Thursday through Friday night]...
Unsettled conditions are expected through the short term as weak
upper level troughing and deep moisture remain across the area. A
weak surface trough will slide south into the area and stall
around Friday, which will likely keep rain chances elevated above
climatology. With precipitable water values greater than 2 inches,
some pockets of locally heavy rain will probably also occur. We
will have to monitor for localized flooding by the end of the
short term and into the long term in this wet pattern, but at this
time it is tough to pick out any one day or specific area to focus
on for any potential flooding.
&&
.LONG TERM [Saturday through Wednesday]...
Unsettled conditions will continue through a large portion of the
long term with near to above climo PoPs. The forecast pattern is
rather unusual with both the 10/00z ECMWF and 10/12z GFS showing
an upper level low retrograding southwestward from the northeast
states down to the Gulf coast. There are some detail differences
in the models, but both models signal an overall wet pattern
continuing. Near to slightly below average high temperatures are
forecast given the expected cloud cover.
&&
.AVIATION...[Through 00z Friday]
Mostly VFR conditions expected with exceptions coming with the
widespread storms into this late eve. Visibilities may decrease
are possible in any stronger storms. 11Z-14Z MVFR VSBYS/CIGS and
possible brief IFR conditions especially DHN/ABY and VLD. then VFR
expected expect for MVFR CIGS/VSBYS in any stronger storms and heavy
rain during Thurs aftn and eve.
&&
.MARINE...
Winds and seas will remain low as the marine area remains at the
western periphery of the subtropical Atlantic ridge. This portion
of the ridge will erode at the end of the week as a weakening
cold front approaches and stalls just north of the waters on
Friday and dissipates over the weekend.
&&
.FIRE WEATHER...
Humid conditions are expected for the foreseeable future with
scattered to numerous showers and thunderstorms increasing over
the weekend as a cold front reaches the area. Relative humidities
will remain high and there are no fire weather concerns.
&&
.HYDROLOGY...
We appear to be headed into another stretch of wet weather over
the next 7-10 days based on the latest model guidance. Unlike the
round of heavy rainfall in early July, there is not much agreement
yet on a particular area where the heaviest rain totals may be
focused. Therefore, the outlook (in terms of hydrology) is just
for heavy rainfall and the possibility of some flooding issues
again. The 7-day WPC QPF calls for widespread 2-3 inch totals over
our entire area, which is very close to model ensemble mean
values. Of course, there are likely to be localized values well in
excess of that.
Even taking the 2-3 inch rain forecast literally (which is pretty
close to the majority of the NAEFS members) and applying it to
MMEFS forecasts for river points in our area does produce some
chance of flooding on a few of the rivers.
Rivers Most At-Risk For Continued / Developing Flooding July 10-20
------------------------------------------------------------------
Aucilla River, St. Marks River, Withlacoochee River near Valdosta,
the Choctawhatchee River (particularly lower portions), and the
Apalachicola River. Only change since this afternoon is that due
to heavy rains, Auculla back to minor flooding.
Of course, given high flows on many rivers due
to recent rainfall, it would be impossible to totally rule out
rises and/or flooding on any of our area rivers. Where localized
heavy rainfall sets up will be the main concern - as it will have
the potential to produce flash flooding, as well as more
considerable rises on rivers. After several days of rain, the more
at-risk areas may be easier to pinpoint. The bottom line is that
those with interests along area rivers, streams, and creeks, and
in flood-prone areas should keep a close eye on forecasts over the
next 7-10 days.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 72 89 72 88 71 / 40 70 50 70 50
Panama City 75 88 74 86 74 / 40 70 60 70 50
Dothan 73 89 72 89 72 / 50 70 50 60 30
Albany 74 90 72 89 71 / 50 70 50 70 40
Valdosta 71 90 71 88 70 / 30 70 50 70 40
Cross City 71 89 71 89 71 / 30 60 40 70 50
Apalachicola 74 87 74 85 74 / 30 60 50 70 50
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
Near Term/Aviation/Marine...Block
Short Term/Long Term...DVD
Fire Weather...Block
Hydrology...Block/Lamers
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
325 PM EDT TUE JUL 9 2013
.SYNOPSIS...
19Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS AN UNAMPLIFIED UPPER LEVEL
PATTERN WITH THE MAIN NORTHERN STREAM FLOW ALIGNED ZONALLY OVER THE
U.S/CANADIAN BORDER. TO THE SOUTH OF THE NORTHERN STREAM WE FIND A
BROAD EXPANSE OF UPPER LEVEL RIDGING IN PLACE ACROSS MUCH OF THE
SOUTHERN TIER OF THE CONUS. ONE OTHER FEATURE OF NOTE IS A TUTT
FEATURE/UPPER LOW SLOWLY MIGRATING WESTWARD FROM THE BAHAMAS TOWARD
THE SOUTHERN FL PENINSULA. THIS TUTT FEATURE MAY BRING SOME ENHANCED
RAIN CHANCES TO THE AREA ON WEDNESDAY...ESPECIALLY FOR THE SOUTHERN
HALF OF THE PENINSULA...BUT OVERALL WILL BE IN A WEAKENING PHASE IN
TERMS OF ITS NEGATIVE THERMAL ANOMALY...AND THIS SHOULD LIMIT THE
OVERALL POSITIVE INSTABILITY IMPACT THAT TUTT CELLS CAN HAVE TOWARD
DIURNAL CONVECTION THIS TIME OF YEAR.
AT THE SURFACE...HIGH PRESSURE IS ALIGNED FROM OFF THE GA/SC COAST
WESTWARD ALONG OR JUST NORTH OF THE I-10 CORRIDOR. WE FIND OUR
FORECAST AREA SITUATED BETWEEN THIS RIDGE AXIS AND A WEAK INVERTED
TROUGH ALONG THE FL SE COAST. THIS TROUGH IS REALLY JUST THE SURFACE
REFLECTION OF THE TUTT...AND IS PROGGED BY THE LATEST NAM/GFS AND
LOCAL HI-RES MODELS TO MIGRATE IN ADVANCE OF THE UPPER LEVEL FEATURE
ACROSS TO THE SOUTHWEST PENINSULA COAST BY THIS EVENING. THE ADDED
LOW LEVEL FOCUS ASSOCIATED WITH THIS WEAK TROUGH MAY HELP TO ENHANCE
THE DIURNAL THUNDERSTORM ACTIVITY FOR OUR SOUTHERN COASTAL ZONES
LATER THIS AFTERNOON.
.SHORT TERM (TONIGHT THROUGH THURSDAY)...
REST OF THE AFTERNOON THROUGH MID EVENING...
12Z KTBW SOUNDING WAS A BIT ON THE DRY SIDE...AND WOULD NOT BE AN
UNFAVORABLE PROFILE TO SUPPORT A FEW WET-MICROBURSTS WITH ANY
STRONGER LATE DAY STORMS. HOWEVER...NUMERICAL GUIDANCE DOES INDICATE
THAT DRIEST OF THE MID-LEVEL AIR WILL MODIFY SOMEWHAT BY THIS
EVENING AND DECREASE THIS THETA-E DIFFERENCE FROM THE SURFACE. THE
BEST POSITIVE MOISTURE ADVECTION WILL CERTAINLY BE DOWN TOWARD FT.
MYERS. THE NET RESULT OF THIS WOULD LIKELY TO FURTHER ENHANCE THE
STORM COVERAGE SOUTH OF TAMPA BAY...BUT LIMIT THE POTENTIAL WIND
IMPACTS FROM ANY STRONGER STORMS. FROM TAMPA BAY NORTHWARD...THE
DRIER COLUMN SHOULD KEEP THE ACTIVITY MORE SCATTERED...BUT ANY
STRONGER STORMS WILL NEED TO BE WATCHED CLOSELY FOR STRONG WIND
GUST POTENTIAL.
TONIGHT...
LINGERING EVENING STORMS WILL SHIFT OFFSHORE AND WEAKEN DURING THE
MID/LATE EVENING HOURS. THE WEAK UPPER LEVEL SUPPORT FROM THE TUTT
IS LIKELY TO AID ANY TYPICAL NOCTURNAL LAND BREEZE CONVECTION OVER
THE WATER. HAVE INCREASED POPS AFTER MIDNIGHT AWAY FROM THE COAST
INTO THE CHANCE 30-40% RANGE. JUST SOMETHING TO KEEP IN MIND FOR
THOSE PLANNING TO BOAT EARLY IN THE MORNING.
WEDNESDAY/WEDNESDAY NIGHT...
TUTT CELL WILL STALL NEAR THE FLORIDA WEST COAST AND SLOWLY
DISSIPATE. NOT EXPECTING ANY SIGNIFICANT IMPACTS FOR THIS FEATURE
OTHER THAN SOME SLIGHT INCREASE IN COLUMN MOISTURE AND WEAK CYCLONIC
FLOW ALOFT. COVERAGE OF SHOWERS AND STORMS IS LIKELY TO BE HIGHER ON
A REGION-WIDE SCALE DURING THE AFTERNOON HOURS TOMORROW AS A RESULT
OF THESE FACTORS...BUT OVERALL NOT AN OVERLY UNUSUAL WEATHER
SITUATION FROM WHAT WOULD BE EXPECTED FOR JULY.
THURSDAY/THURSDAY NIGHT...
UPPER PATTERN WILL BEGIN TO AMPLIFY ACROSS THE EASTERN STATES. THE
FL PENINSULA WILL BE ON THE BASE OF THIS TROUGH WITH ONLY LIMITED
SYNOPTIC INFLUENCE. ONCE AGAIN RAIN COVERAGE WILL LIKELY BE FAIRLY
HIGH ON THURSDAY AFTERNOON/EVENING...ALTHOUGH SIMILAR TO
WEDNESDAY...THE TEMPORAL LENGTH OF RAINFALL AT ANY ONE LOCATION WILL
LIKELY NOT BE THAT GREAT.
&&
.LONG TERM (THURSDAY NIGHT-TUESDAY)...
TROPICAL STORM CHANTAL REMAINS THE MAIN FORECAST CHALLENGE THROUGH
THE LONG TERM PERIODS. THE LATEST FORECAST FROM THE NATIONAL
HURRICANE CENTER CONTINUES TO SHOW THE SYSTEM MOVING NORTHWESTWARD
THROUGH THE BAHAMAS LATE IN THE WEEK AND OVER THE UPCOMING
WEEKEND. MODEL SOLUTIONS OFFER A VARIETY OF SOLUTIONS WITH THE 00Z
GFS SHOWING THE SYSTEM TAKING A WESTWARD TRACK ACROSS CENTRAL
FLORIDA EARLY NEXT WEEK...THE 00Z CANADIAN SHOWING A WELL DEFINED
SYSTEM MAKING LANDFALL ACROSS SOUTHEAST GEORGIA OR SOUTHERN SOUTH
CAROLINA LATE IN THE WEEKEND...WHILE THE 00Z ECMWF SHOWS NOTHING
MORE THAN SOME UPPER LEVEL ENERGY SHEARING OUT OFF THE EAST COAST
OF FLORIDA OVER THE UPCOMING WEEKEND. GIVEN THE FORECAST TRACK
TAKING CHANTAL OVER THE HIGHER TERRAIN OF HISPANIOLA...WOULD NOT
EXPECT A VERY STRONG SYSTEM TO EMERGE BACK OVER THE ATLANTIC LATE
IN THE WEEK AND OVER THE UPCOMING WEEKEND...SO WILL TRY TO
MAINTAIN AS MUCH FORECAST CONTINUITY AS POSSIBLE AND LEAN THE
FORECAST HEAVILY IN THE DIRECTION OF THE 00Z ECMWF. AS A
RESULT...WILL CONTINUE TO HIGHLIGHT A MORE TYPICAL SUMMERTIME
REGIME WITH SCATTERED SHOWERS AND THUNDERSTORMS EACH DAY AND
TEMPERATURES REMAINING CLOSE TO CLIMATOLOGY.
&&
.AVIATION...
ANTICIPATE SCT TSRA THIS AFTERNOON...WITH LCL MFR/LIFR PGD/FMY/RSW.
TSRA REACHING LAL/TPA/PIE/SRQ WILL BE LATER AND PERHAPS MORE
LIMITED...HAVE OPTED TO HOLD AT VCTS. EAST AND SE WINDS...GUSTY NEAR
TSRA...SHIFTING TO ONSHORE THIS AFTERNOON AT TPA/PIE/SRQ.
&&
.MARINE...
A WEAK PRESSURE GRADIENT WILL REMAIN ACROSS MUCH OF THE EASTERN GULF
OF MEXICO THROUGH THURSDAY KEEPING WINDS AND SEAS BELOW HEADLINE
CRITERIA OUTSIDE OF A TYPICAL DISTRIBUTION OF SHOWERS AND STORMS.
&&
.FIRE WEATHER...
NO SIGNIFICANT FIRE WEATHER CONCERNS EXPECTED THROUGH MIDWEEK AS
RELATIVE HUMIDITY VALUES REMAIN WELL ABOVE CRITICAL LEVELS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 74 90 76 90 / 30 50 30 50
FMY 72 92 73 91 / 30 50 30 50
GIF 72 92 73 92 / 10 50 20 50
SRQ 73 89 74 89 / 30 50 30 50
BKV 69 92 71 91 / 20 50 30 50
SPG 78 90 77 89 / 30 40 30 50
&&
$$
SYNOPSIS/SHORT TERM/MARINE/FIRE WX...MROCZKA
LONG TERM...JELSEMA
AVIATION...RUDE
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
1125 AM EDT TUE JUL 9 2013
.UPDATE...
15Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS AN UNAMPLIFIED UPPER LEVEL
PATTERN WITH THE MAIN NORTHERN STREAM FLOW ALIGNED ZONALLY OVER THE
U.S/CANADIAN BORDER. TO THE SOUTH OF THE NORTHERN STREAM WE FIND A
BROAD EXPANSE OF UPPER LEVEL RIDGING IN PLACE ACROSS MUCH OF THE
SOUTHERN TIER OF THE CONUS. ONE OTHER FEATURE OF NOTE IS A TUTT
FEATURE/UPPER LOW SLOWLY MIGRATING WESTWARD FROM THE BAHAMAS TOWARD
THE SOUTHERN FL PENINSULA. THIS TUTT FEATURE MAY BRING SOME ENHANCED
RAIN CHANCES TO THE AREA ON WEDNESDAY...ESPECIALLY FOR THE SOUTHERN
HALF OF THE PENINSULA...BUT OVERALL WILL BE IN A WEAKENING PHASE IN
TERMS OF ITS NEGATIVE THERMAL ANOMALY...AND THIS SHOULD LIMIT THE
OVERALL POSITIVE INSTABILITY IMPACT THAT TUTT CELLS CAN HAVE TOWARD
DIURNAL CONVECTION THIS TIME OF YEAR.
AT THE SURFACE...HIGH PRESSURE IS ALIGNED FROM OFF THE GA/SC COAST
WESTWARD ALONG OR JUST NORTH OF THE I-10 CORRIDOR. WE FIND OUR
FORECAST AREA SITUATED BETWEEN THIS RIDGE AXIS AND A WEAK INVERTED
TROUGH ALONG THE FL SE COAST. THIS TROUGH IS REALLY JUST THE SURFACE
REFLECTION OF THE TUTT...AND IS PROGGED BY THE LATEST NAM/GFS AND
LOCAL HI-RES MODELS TO MIGRATE IN ADVANCE OF THE UPPER LEVEL FEATURE
ACROSS TO THE SOUTHWEST PENINSULA COAST BY THIS EVENING. THE ADDED
LOW LEVEL FOCUS ASSOCIATED WITH THIS WEAK TROUGH MAY HELP TO ENHANCE
THE DIURNAL THUNDERSTORM ACTIVITY FOR OUR SOUTHERN COASTAL ZONES
LATER THIS AFTERNOON.
REST OF TODAY...
ANOTHER COUPLE HOURS OF GENERALLY DRY CONDITIONS FOR OUR ZONES
BEFORE THE DIURNAL CONVECTION BEGINS TO FOCUS. SIMILAR TO PREVIOUS
DAYS...RAIN CHANCES...ESPECIALLY NEAR THE COAST WILL PEAK DURING THE
LATE AFTERNOON/EVENING HOURS. 12Z KTBW SOUNDING WAS A BIT ON THE DRY
SIDE...AND WOULD NOT BE AN UNFAVORABLE PROFILE TO SUPPORT A FEW
WET-MICROBURSTS WITH ANY STRONGER LATE DAY STORMS.
HOWEVER...NUMERICAL GUIDANCE DOES INDICATE THAT DRIEST OF THE
MID-LEVEL AIR WILL MODIFY SOMEWHAT BY THIS EVENING AND DECREASE THIS
THETA-E DIFFERENCE FROM THE SURFACE. THE BEST POSITIVE MOISTURE
ADVECTION WILL CERTAINLY BE DOWN TOWARD FT. MYERS. THE NET RESULT OF
THIS WOULD LIKELY TO FURTHER ENHANCE THE STORM COVERAGE SOUTH OF
TAMPA BAY...BUT LIMIT THE POTENTIAL WIND IMPACTS FROM ANY STRONGER
STORMS. FROM TAMPA BAY NORTHWARD...THE DRIER COLUMN SHOULD KEEP THE
ACTIVITY MORE SCATTERED...BUT ANY STRONGER STORMS WILL NEED TO BE
WATCHED CLOSELY FOR STRONG WIND GUST POTENTIAL.
LINGERING EVENING STORMS WILL SHIFT OFFSHORE AND WEAKEN DURING THE
MID/LATE EVENING HOURS. THE WEAK UPPER LEVEL SUPPORT FROM THE TUTT
IS LIKELY TO AID ANY TYPICAL NOCTURNAL LAND BREEZE CONVECTION OVER
THE WATER. HAVE INCREASED POPS AFTER MIDNIGHT AWAY FROM THE COAST
INTO THE CHANCE 30-40% RANGE. JUST SOMETHING TO KEEP IN MIND FOR
THOSE PLANNING TO BOAT EARLY IN THE MORNING.
&&
.AVIATION...
MAINLY VFR CONDITIONS BUT WITH A CHANCE OF TSRA IN THE AFTERNOON.
WILL HANDLE WITH VCNTY REMARK FOR NOW. EASTERLY WINDS SHIFT TO
ONSHORE IN THE AFTERNOON ALONG THE COAST.
&&
.MARINE...
A FAIRLY WEAK PRESSURE PATTERN IS EXPECTED ACROSS THE WATERS THROUGH
THE FORECAST PERIOD...WITH THE ONLY POTENTIAL CAVEAT BEING THE TRACK
OF TROPICAL STORM CHANTAL OR IT/S REMNANT LOW OVER THE WEEKEND AND
INTO EARLY NEXT WEEK. THE LATEST FORECAST FROM THE NATIONAL
HURRICANE CENTER CONTINUES TO SHOW THE SYSTEM MOVING NORTHWARD WELL
OFF THE EAST FLORIDA COAST...WHICH WOULD RESULT IN LITTLE IF ANY
IMPACT ON THE LOCAL MARINE AREA. AS A RESULT...WINDS AND SEAS ARE
EXPECTED TO REMAIN BELOW HEADLINE THRESHOLDS THROUGH THE FORECAST
PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 91 75 90 76 / 40 30 40 30
FMY 91 72 91 74 / 50 20 50 30
GIF 91 72 91 74 / 30 10 30 20
SRQ 91 73 89 74 / 40 30 40 20
BKV 93 70 91 71 / 40 20 40 30
SPG 92 77 90 77 / 40 30 40 20
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE...MROCZKA
AVIATION...RUDE
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
331 AM EDT TUE JUL 9 2013
.DISCUSSION...
TODAY-TONIGHT...THERE WAS LITTLE CHANGE WITH THE 00Z GFS. IT WAS
STILL SHOWING MID/UPPER LEVEL (TUTT) LOW PRESENTLY CENTERED NEAR
ANDROS ISLAND PUSHING WEST NORTHWEST INTO THE SOUTHERN TIP OF THE
FLORIDA PENINSULA. ATMOSPHERE WILL GRADUALLY MOISTEN...ESPECIALLY
ACROSS THE SOUTH HALF OF THE AREA...WHILE WEAK VORT MAXIMA ROTATE
AROUND THE LOW AND INCREASE LIFT.
MOS POPS TODAY RANGE FROM 50 PERCENT IN THE FAR SOUTH TO 30
PERCENT ELSEWHERE. EVEN THOUGH THE GFS IS NOT GENERATING MUCH
PRECIP...WILL GO WITH 40-50 PERCENT POPS ALONG THE TREASURE COAST
SINCE THERE IS A DECENT SWATH OF SHOWERS ABOUT 100 MILES OFFSHORE
SOUTH OF CANAVERAL. ELSEWHERE WILL STAY CLOSE TO THE PREVIOUS
FORECAST...30 PERCENT...EXCEPT 20 PERCENT ALONG THE NORTH COAST
WHERE THE GFS AND NAM GENERATE NO PRECIP.
COOLING ALOFT IS SHOWN BY THE LATEST RAP ANALYSIS WITH LIGHTNING
DETECTION EQUIPMENT SHOWING A FEW STRIKES EAST OF OUR COASTAL
WATERS. THEREFORE EXPECT THAT AFTER A SEVERAL DAY HIATUS FROM
LIGHTNING...THERE WILL BE A RETURN OF ISOLATED STORMS...ESPECIALLY
INLAND AND OVER THE COASTAL WATERS.
WEDNESDAY/THURSDAY...LITTLE CHANGE TO THE MID WEEK FORECAST AS TUTT
CURRENTLY OVER THE BAHAMAS TRACKS ACROSS SOUTH FLORIDA ON
WEDNESDAY...BEFORE BEING ABSORBED INTO LARGER SCALE UPPER TROUGH
SWINGING THROUGH THE EASTERN CONUS ON THURSDAY. AT THE SAME TIME THE
LOW LEVEL WESTERN ATLC RIDGE WILL SLIDE SOUTH IN RESPONSE TO THE
FRONTAL TROUGH MOVING THROUGH THE EASTERN AND SOUTHEASTERN
US...ENDING UP OVER OR JUST SOUTH OF THE AREA BY THURSDAY.
FLOW WILL BE WEAK ENOUGH FOR BOTH SEA BREEZES TO FORM EACH
AFTERNOON...WITH THE STEERING FLOW SHIFTING FROM SOUTH-SOUTHEAST ON
WEDNESDAY TO SOUTHWEST ON THURSDAY AS THE AREA GETS SQUEEZED IN
BETWEEN THE LARGER UPPER LEVEL TROUGH TO THE NORTH AND WESTERN
ATLANTIC RIDGE NOSING IN.
THE TUTT WILL BRING COLDER TEMPS ALOFT...ESPECIALLY ACROSS THE
SOUTH...AND THE DEEPER MOISTURE WILL SUPPORT RAIN CHANCES AT OR
JUST ABOVE NORMAL AT 40-50 PERCENT.
FRIDAY/WEEKEND...UPPER LEVEL EAST COAST TROUGH DEEPENS ON
FRIDAY...WITH THE SOUTHERN EXTENT OF THE TROUGH SPLITTING ON
SATURDAY. THIS WILL LEAVE ANOTHER UPPER LEVEL LOW TO MEANDER
SOUTHWESTWARDS ACROSS THE DEEP SOUTH AND WESTERN GULF OF MEXICO BY
THE END OF THE WEEKEND.
AT THE SURFACE...THE OFFICIAL TRACK FOR TS CHANTAL HAS IT MOVING
THROUGH THE CENTRAL AND NORTHERN BAHAMAS FRIDAY AND SATURDAY WITH
SOME QUESTION AS TO IF IT WILL SURVIVE THE EFFECTS OF LAND
INTERACTION AND WIND SHEAR AFTER IT CROSSES HISPANIOLA LATE THURSDAY.
WHAT INFLUENCE THE SYSTEM OR ITS REMNANTS WILL PLAY IN THE LOCAL
WEATHER FOR THE WEEKEND IS STILL UNCLEAR. WILL KEEP POPS NEAR
CLIMO THROUGH THE PERIOD AS FUTURE FORECASTS FOR CHANTAL UNFOLD.
&&
.AVIATION...
LOCAL MVFR IN ONSHORE MOVING SHOWERS MAINLY KMLB-KSUA WITH SLIGHT
CHANCE FOR LIGHTNING IN THE VICINITY...ESPECIALLY THIS MORNING AND
EARLY AFTERNOON. PROBABILITY FOR THESE CONDITIONS IN THE AFTERNOON
FROM KISM/KMCO TO KSFB/KLEE ARE TOO LOW TO MENTION IN TAFS YET.
&&
.MARINE...
TODAY-TONIGHT...SURFACE RIDGE AXIS SETTLING INTO NORTH FLORIDA
WILL REDUCE THE ONSHORE FLOW TO 10 KNOTS OR LESS. THERE WILL BE
ISOLATED TO SCATTERED SHOWERS AND A FEW LIGHTNING STORMS...
ESPECIALLY SOUTH OF CANAVERAL.
WED-SAT...SOUTH-SOUTHEAST WINDS ON WEDNESDAY AND THURSDAY INTO
THE END OF THE WEEK AS THE ATLANTIC RIDGE AXIS SLIDES INTO CENTRAL
FLORIDA. SPEEDS AROUND 10-15KTS THROUGH THE PERIOD...WITH A
STRONGER ONSHORE COMPONENT DEVELOPING NEARSHORE EACH AFTERNOON
WITH THE EAST COAST SEA BREEZE. SEAS 2-4FT.
FORECAST FROM SATURDAY ONWARDS BECOMES HIGHLY UNCERTAIN AS TC
CHANTAL...OR ITS REMNANTS...ARE FORECAST TO BE IN THE CENTRAL AND
NORTHERN BAHAMAS BY LATE FRIDAY INTO SATURDAY. WIND SPEEDS/DIRECTION
AND SEAS WILL BE HIGHLY DEPENDENT ON HOW CHANTAL EVOLVES.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 89 72 89 74 / 20 20 30 20
MCO 92 71 92 73 / 30 10 30 20
MLB 89 73 89 75 / 30 20 40 30
VRB 88 71 89 74 / 40 20 40 30
LEE 92 72 93 75 / 20 10 40 20
SFB 92 73 93 75 / 30 10 30 20
ORL 92 73 93 76 / 30 10 30 20
FPR 87 71 88 74 / 40 20 50 30
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM/AVIATION...LASCODY
LONG TERM....MOSES
AREA FORECAST DISCUSSION
NWS LINCOLN IL
215 PM CDT TUE JUL 9 2013
.DISCUSSION...
ISSUED 200 PM CDT TUE JUL 9 2013
BAND OF CONVECTION THAT FIRED EARLY THIS MORNING ACROSS IOWA HAS
PUSHED EAST INTO NORTH CENTRAL IL JUST AHEAD OF A MID LEVEL
SHORTWAVE. UPSTREAM FROM THAT WAVE IS A MORE SIGNIFICANT SHORTWAVE
OVER NORTH DAKOTA THAT WILL BRING AN END TO THE HEAT AND HUMIDITY
ALONG WITH THE THREAT FOR RAIN. AT THE SURFACE...THE 18Z ANALYSIS
INDICATES A WEAK OUTFLOW BOUNDARY FROM THE MORNING CONVECTION LOCATED
FROM JUST WEST OF LACON AND EAST OF PEORIA AND SPRINGFIELD. THERE
WAS A MIX OF SUN AND CLOUDS EARLY THIS AFTERNOON WITH TEMPERATURES
CURRENTLY RANGING FROM THE UPPER 80S TO LOWER 90S WITH HEAT INDEX
VALUES AROUND 100.
SHORT TERM...TONIGHT THROUGH FRIDAY
SEVERE STORM THREAT TONIGHT THE MAIN FORECAST CHALLENGE. WILL FOLLOW
THE HRRR AND THE NCEP HI-RES ARW MODELS AS THEY HAVE SHOW A BIT MORE
CONSISTENCY WITH THE DEVELOPMENT OF CONVECTION LATER THIS AFTERNOON
AND ESPECIALLY TONIGHT ALONG THE SOUTHEASTWARD MOVING COLD FRONT.
WILL GRADUALLY PROGRESS THE HIGHEST POPS FROM NW TO SE OVERNIGHT AS
THE COLD FRONT SETTLES INTO THE REGION. FORECAST SOUNDINGS STILL CONTINUE
TO SHOW AN INCREASE IN MID LEVEL WINDS CONINCIDENT WITH HIGH CAPE VALUES
TONIGHT IN ADVANCE OF THE STRONGER UPPER LEVEL FORCING. AS A RESULT...A
FEW OF THE STORMS WILL BE CAPABLE OF PRODUCING DAMAGING WIND GUSTS AND
TORRENTIAL RAINFALL WITH PRECIP WATER VALUES AROUND 2 INCHES. ASSUMING
ORGANIZED CONVECTION DOES DEVELOP TO OUR NORTHWEST THIS EVENING...THE
EFFECTIVE OUTFLOW BOUNDARY SHOULD BE PRESSING SE INTO THE I-70 CORRIDOR
BY MORNING WITH THE ACTUAL SYNOPTIC COLD FRONT LAGGING BEHIND.
POPS WILL LOWER FROM NW TO SE TOMORROW MORNING IN ANTICIPATION OF
THE COLD FRONT SLIPPING SE OF I-70 BY 21Z. MAIN QUESTION IS WHETHER
ANY STORMS CAN REFIRE AHEAD OF THE FRONT TOMORROW AFTN. IF WE SEE
VERY LITTLE ACTIVITY TONIGHT...CHANCES ARE WE WILL SEE STORMS REFIRE
AHEAD OF THE COLD FRONT ALONG THE I-70 CORRIDOR BEFORE SHIFTING OFF
TO OUR SOUTHEAST BY EVENING. IF STORMS DO ORGANIZE...AND TRACK QUICKLY
SE LATE TONIGHT...WE MAY NOT SEE ANY DEVELOPMENT ACRS THE SOUTHEAST
TOMORROW AFTN. STILL SOME UNCERTAINTY WITH RESPECT TO FRONTAL POSITION
ACRS SE IL SO WILL CONTINUE TO KEEP POPS GOING DOWN THERE THRU THE
AFTN HOURS.
PACIFIC HIGH PRESSURE WILL THEN BUILD EAST INTO THE MIDWEST BRINGING
IN COOLER AND LESS HUMID AIR STARTING WEDNESDAY NIGHT AND CONTINUING
THRU THE REST OF THE WORK WEEK. ONE MORE HOT AND HUMID DAY FOR THE
SOUTHEAST WITH TEMPERATURES RISING INTO THE LOWER 90S WITH HEAT INDEX
VALUES AT OR JUST ABOVE 100. AFTER THAT... WE SHOULD AFTERNOON TEMPS
DROP BACK INTO THE LOW TO MID 80S AND SURFACE DEW POINTS BACK TO THE
UPPER 50S TO LOWER 60S THURSDAY AND ESPECIALLY ON FRIDAY.
LONG TERM...SATURDAY THROUGH TUESDAY
UPPER LEVEL RIDGING STILL FORECAST TO BUILD OVER THE CENTER OF THE
NATION DURING THIS PERIOD BRINGING RELATIVELY QUIET WEATHER TO OUR
AREA. STRONGER MID LEVEL FLOW WILL SHIFT WELL TO OUR NORTH WITH
TEMERATURES RISING BACK INTO THE UPPER 80S TO AROUND 90 BY SUNDAY
AND MONDAY.
SMITH
&&
.AVIATION...
ISSUED 1245 PM CDT TUE JUL 9 2013
SATELLITE IMAGERY SHOWS SOME BREAKUP OF THE CLOUDS OVER CENTRAL IL
LAST FEW HOURS...AS THE MUCAPES HAVE REACHED TO 3000. SURFACE DATA
HAS SHOWN SOME BOUNDARY INTERACTION IN THE REGION MAY LATER
TRIGGER CONVECTION. MOST OF CLOUDINESS OVER REGION IS MID WITH
SPOTTY SCT LOW CLOUDS. KEPT TREND OF VCNTY PCPN UNTIL MAIN FRONTAL
ACTIVITY APPROACHS OVERNIGHT. OVERALL...FEW CHANGES.
GOETSCH
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
123 PM CDT TUE JUL 9 2013
.DISCUSSION...
1144 AM CDT
FOR MORNING UPDATE...
NO SIGNIFICANT CHANGES TO GOING FORECAST FOR THE MOST PART OTHER
THAN REFINING POPS/WX AND TIMING OF WAVES OF SHOWERS/STORMS.
AN AREA OF SHOWERS AND THUNDERSTORMS WILL CONTINUE TO SPREAD EAST
ACROSS THE AREA THROUGH MIDDAY AHEAD OF A MID-LEVEL SHORT WAVE
TROUGH APPROACHING THE MID/UPPER MISSISSIPPI VALLEY. AS EXPECTED...
RELATIVELY WEAK MID/UPPER LEVEL FLOW RESULTING IN WEAK BULK SHEAR
MAGNITUDE...WITH LOOSELY ORGANIZED MCS PRESENTING MAINLY A LOCALLY
HEAVY RAIN THREAT GIVEN PWATS AROUND 2.00 INCHES.
THROUGH THIS AFTERNOON...MID-LEVEL TROUGH IS PROGGED TO MOVE EAST
ACROSS IL/WI...WITH ENHANCED VORTICITY/MCV OVER CENTRAL IA EXPECTED
TO HELP MAINTAIN AREA OF STORMS CURRENTLY OVER EASTERN/SOUTHEAST IA.
DESPITE IMPACT OF CLOUDS/SCATTERED PRECIP COVERAGE...THE COMBINATION
OF INCREASING MID-LEVEL FLOW AND DEEP SHEAR ALONG WITH DIURNAL
DESTABILIZATION IN WARM/MOIST AIR MASS WILL LIKELY RESULT IN AN
INCREASED COVERAGE AND ORGANIZATION TO STORMS DURING LATE AFTERNOON
AND EARLY EVENING HOURS...INCREASING SEVERE THREAT ALONG WITH
ONGOING HEAVY RAINFALL POTENTIAL. RECENT RUNS OF RAP/HRRR SEEM TO
HAVE A DECENT OVERALL HANDLE ON CURRENT ACTIVITY...AND SUPPORT THE
IDEA OF THE LINE OVER EASTERN IA MOVING ACROSS THE AREA FROM
MID-AFTERNOON INTO EARLY THIS EVENING.
RATZER
//PREV DISCUSSION...
340 AM CDT
SEVERE WEATHER AND HEAVY RAIN POTENTIAL THROUGH TONIGHT WAS WHAT
MUCH OF THE ANALYSIS TIME WAS SPENT ON THIS MORNING. WHAT MAINLY
WAS TRYING TO DO WAS LOCK DOWN A TIMING FOR AN IMPROVED SEVERE
WEATHER THREAT /MID-AFTERNOON THROUGH EARLY OVERNIGHT THOUGH AIR
MASS CAN ALLOW FOR ISOLATED SEVERE ANYTIME/...AND WHAT MAIN
THREATS WOULD BE /WIND AND HEAVY RAIN/. OVERALL NO MAJOR CHANGES
MADE TO THE FORECAST...JUST INCREASING POPS IN THOSE MOST FAVORED
TIMES...RE-ORIENTING POPS SOME...AND REFINING RAINFALL AMOUNT
FORECASTS.
SYNOPSIS...A VERY SOUPY AIR MASS IS ENTRENCHED IN THE REGION
THIS MORNING WITH MID 70S DEW POINTS ACROSS THE FORECAST AREA AND
PWATS ON LAST EVES REGIONAL RAOBS AND EARLY MORNING OBJECTIVE
ANALYSIS BEING AROUND 2 INCHES. NUMEROUS SHORT WAVE IMPULSES...MANY
WITH ASSOCIATED CLUSTERS OF CONVECTION...ARE FOUND UPSTREAM ACROSS
THE HIGH PLAINS AND OVER THE WESTERN CORN BELT ON GOES WATER VAPOR
IMAGERY. THE PRIMARY UPPER LEVEL SHORT WAVE TROUGH WILL BE
DIGGING INTO EASTERN MT SOON AFTER DAYBREAK AND WILL BE THE
RESPONSIBLE PARTY FOR ENDING THIS MOIST AIR MASS...AT LEAST
TEMPORARILY BY LATER WED. AT THE SURFACE A FAIRLY DIFFUSE
GRADIENT EXISTS EARLY TODAY WITH A WEAK STATIONARY BOUNDARY NEAR
THE STATE LINE. THE WEAK FLOW HAS ALLOWED FOR LOW CLOUDS AND FOG
TO BE EXPANDING THEIR WAY SOUTHWARD DOWN LAKE MI AIDED BY AMBIENT
DEW POINTS EXCEEDING THE WATER TEMPS BY SEVERAL DEGREES. THE
PRIMARY SURFACE FRONT IS TAKING SHAPE ACROSS THE HIGH PLAINS AND
WILL DEVELOP INTO A COOL FRONT LATER TODAY AS SURFACE CYCLOGENESIS
OCCURS THROUGH NORTHERN MN INTO WESTERN ONTARIO BY THIS EVE. THIS
FRONT WILL MOVE INTO THE FORECAST AREA LATE TONIGHT INTO EARLY WED
MORNING. MULTIPLE ROUNDS OF CONVECTION ARE LIKELY AHEAD OF THIS.
MODEL PREFERENCE...THE RAP AND HRRR GUIDANCE HAVE A GOOD
REPRESENTATION OF ONGOING CONVECTION. THESE HAVE THE SUPPORT OF
SEVERAL OTHER CONVECTIVE ALLOWING MODELS AND HAVE BEEN GUIDED ON
THROUGH MID-AFTERNOON. AFTERWORDS HAVE LEANED TOWARD THE SLIGHTLY
SLOWER 09.00 NAM THAN GFS.
THIS MORNING...REMNANT MCV/SHORT WAVE ENTERING WESTERN IL EARLY
THIS MORNING HAS BEGUN TO INCREASE RADAR ECHOES ACROSS CENTRAL IL
AND THIS TREND IS LIKELY TO CONTINUE WITH SCATTERED CONVECTION
FAVORED DUE TO MODERATE TO HIGH ELEVATED INSTABILITY. NOT A
PARTICULARLY STRONG LOW-LEVEL JET OR ONE WITH HUGE MOISTURE
TRANSPORT THIS MORNING...DUE TO STILL BEING A GOOD DISTANCE AHEAD
OF MID-LEVEL HEIGHT FALLS. SO MORNING SCATTERED TO NUMEROUS
SHOWERS/STORMS ACROSS CENTRAL IL MAY STRUGGLE TO PROGRESS
NORTH/NORTHEAST AT LEAST AT ANY GOOD CLIP OF SPEED. THUS ROCKFORD
TO CHICAGO HAVE POPS ONLY AT THE CHANCE LEVEL...AND MORE SO BASED
ON ISOLATED CELLS DEVELOPING IN THE BROAD WAA AND HIGH PWAT
REGIME. WITH SUCH HIGH PWATS AS YESTERDAY MORNING SHOWED...LOCALLY
HEAVY RAINFALL WOULD BE THE PRIMARILY ASPECT TO KEEP AN EYE ON
WITH THESE MORNING AND EARLY AFTERNOON STORMS. AS FOR EARLY
MORNING FOG/STRATUS THAT HAS BEEN DEVELOPING IN PLACES...ONSHORE
FLOW MAY FAVOR PATCHES OF THIS TO CONTINUE THROUGH MID OR EVEN
LATE MORNING ACROSS NORTHEAST IL AND FAR NORTHWEST IN...STUNTING A
TEMPERATURE CLIMB INITIALLY. OTHERWISE THIS LOOKS LIKE IT SHOULD
BEGIN DISSIPATING/RETREATING NORTH AFTER THAT TIME.
CONFIDENCE...HIGH.
THIS AFTERNOON THROUGH TONIGHT...THE END OF THE RAP RUN AGREES
CLOSELY WITH THE NAM IN TAKING THE SHORT WAVES AND ASSOCIATED 500
AND 700MB SPEED MAXS ACROSS THE DAKOTAS AND NORTHERN NEBRASKA
EARLY THIS MORNING AND TRACKING THAT EAST INTO SOUTHERN WI AND
NORTHERN IL BY MID TO LATE AFTERNOON. ON THE SYNOPTIC SCALE AT
THAT TIME...THE LOW-LEVEL JET AND MOISTURE TRANSPORT WILL ALSO BE
ON THE EXPANSE FROM MO INTO EASTERN IA/WESTERN IL. MIXED LAYER
INSTABILITY WILL BE HIGH OVER THIS AREA INCLUDING THE WESTERN
FORECAST AREA GIVEN TEMPS IN THE UPPER 80S TO LOWER 90S. WHILE
SOME FORM OF MCS OR MULTIPLE CLUSTERS ARE PROBABLE TO BE MOVING
EASTWARD OVER SOUTHERN WI/FAR NORTHERN IL DURING THE AFTERNOON
WITH THE SHORT WAVES...DEVELOPMENT IS FAVORED TO WORK ITS WAY
SOUTH AND BACK TO THE SOUTHWEST FROM THERE IN THE MOIST UNSTABLE
AIR MASS DURING THE MID-AFTERNOON. DEEP LAYER SHEAR IS ANTICIPATED
TO BE INCREASING TO AROUND 30-35 KT BY LATE AFTERNOON WITH
ORGANIZED STORMS EXPECTED TO BE ALL WORKING THEIR WAY EASTWARD. AS
THE PRIMARY UPPER TROUGH APPROACHES THIS EVENING...LARGER SCALE
ASCENT AND FORCING IS LIKELY TO CONTINUE REGIONAL DEVELOPMENT OF
STORMS NEAR AND AHEAD OF THE SURFACE FRONT. SO WHILE THERE LOOKS
TO BE TWO PRIMARY FOCUSES FOR STORMS THIS AFTERNOON INTO
TONIGHT...THERE IS NOT REALLY ANTICIPATED TO BE MUCH OF A BREAK
AND THE HIGH PWAT AND UNSTABLE AIR SHOULD ALLOW FOR PLENTY OF
COVERAGE. THAT COVERAGE MAY INITIALLY BE A LITTLE LIMITED
DEPENDING ON DEBRIS CLOUD COVER BUT IS ANTICIPATED TO BE ITS
HIGHEST LATER THIS AFTERNOON THROUGH EARLY OVERNIGHT.
THE MOST FAVORED MODE FOR STORMS IS MULTICELL AND SEGMENTS
CAPABLE OF SCATTERED DAMAGING WINDS...ESPECIALLY AS THE STRONGER
MID-LEVEL JET OVERRIDES THE FRONT THIS EVENING INTO EARLY
OVERNIGHT. SOME DEVELOPMENT THIS AFTERNOON THROUGH MID-EVE HAS
THE POTENTIAL TO BE SUPERCELLULAR. THE LOW-LEVEL SHEAR IS FAIRLY
ANEMIC MUCH OF THIS AFTERNOON /AOB 10 KT/ BUT QUICKLY INCREASES
LATE INTO EARLY THIS EVE DUE TO THE DEEPENING LOW AND INCREASING
LLJ. THIS WILL HELP FAVOR COLD POOL SUSTAINABILITY AND DOES PRESENT
AT LEAST SOME TORNADO THREAT...ALTHOUGH IT LOOKS LIKE SURFACE
WINDS MAY BE BACKED MORE TO THE WEST OF THE FORECAST AREA
IMMEDIATELY AHEAD OF A SUBTLE SECONDARY SURFACE LOW MOVING UP THE
FRONT. SO THE PRIMARY THREAT WILL REMAIN WIND AND OF COURSE HEAVY
RAIN WITH EXTREMELY EFFICIENT RAIN PRODUCTION WILL OCCUR IN ANY
STORMS TODAY AND TONIGHT. EVEN THOUGH FORWARD PROPAGATION OF
STORMS SHOULD BE ON THE INCREASE TONIGHT...SO WILL DEEP MOISTURE
REPLENISHMENT AND SIMPLY PUT THE ABSOLUTE MOISTURE IS SO HIGH IT
WONT TAKE MUCH TO GET HIGH RAINFALL RATES SUCH AS WE SAW YESTERDAY
MORNING. THERE WILL LIKELY BE SWATHS OF RAINFALL IN EXCESS OF ONE
TO TWO INCHES ACROSS THE IMMEDIATE REGION...BUT WHERE EXACTLY
THEY OCCUR IS TOO CHALLENGING TO LOCK DOWN. DEBATED ON A FLASH
FLOOD WATCH BUT FEEL THE THREAT IS TOO LOCALIZED AT THIS TIME FOR
A WATCH.
CONFIDENCE...MEDIUM.
WEDNESDAY...ONGOING SCATTERED SHOWERS AND STORMS ARE POSSIBLE
ACROSS MAINLY THE SOUTHERN AND EASTERN FORECAST AREA IN THE
MORNING WITH STILL AT LEAST SOME HEAVY RAIN THREAT. WARM
850-925MB AIR BEHIND THE SURFACE WIND SHIFT WILL STILL FAVORED
HIGHS IN THE MID TO POSSIBLY EVEN UPPER 80S IN THE SOUTH. DRIER
AIR WILL GRADUALLY FILTER IN DURING THE LATER AFTERNOON AND NIGHT
PER GUIDANCE.
CONFIDENCE...HIGH.
THURSDAY THROUGH MONDAY...PRIMARILY DRY WEATHER IS EXPECTED OVER
THE AREA ALTHOUGH THE TREND IN BOTH THE EC AND GFS THEIR LAST
MULTIPLE RUNS SUPPORTS WARMER TEMPERATURES THIS WEEKEND WITH MID
AND MAYBE EVEN UPPER 80S SEEN. HAVE COLLABORATED AND LEANED TOWARD
THE WARMER MEX GUIDANCE. THE PATTERN STILL APPEARS BLOCKED JUST
WITH THE AREA MORE UNDER THE INFLUENCE OF THE UPPER RIDGE TO THE
WEST.
MTF
&&
.HYDROLOGY...
410 AM CDT
THE VERY MOIST AIR MASS WILL SUPPORT EFFICIENT RAINFALL PRODUCTION
FROM ANY THUNDERSTORMS TODAY AND TONIGHT. THIS MAY PRESENT FLASH
FLOODING ESPECIALLY ON THE LOCAL LEVEL AS OPPOSED TO ANY WIDESPREAD
THREAT. THAT AND THE FACT THERE IS NOT A GREAT SET UP FOR TRUE
TRAINING STORMS IS WHY NO FLASH FLOOD WATCH AT THIS TIME.
HOWEVER...IF ANY STORMS ARE IN A PARTICULARLY VULNERABLE
AREA...SUCH AS A METRO OR A QUICK-RESPONDING WATERSHED...IT COULD
BE TROUBLE. THESE TYPE OF HIGH RATES WERE ALREADY SEEN YESTERDAY
MORNING WITH A NARROW SWATH OF ONE AND A HALF TO ESTIMATED THREE
PLUS INCHES OF RAIN SEEN FROM RE-FIRING STORMS IN THE WEST CHICAGO
METRO. HIGH RESOLUTION MODEL GUIDANCE INDICATES SUCH SWATHS ARE
PROBABLE IN THE REGION THIS AFTERNOON INTO TONIGHT ALTHOUGH WHERE
IS STILL UNCERTAIN. THE GENERAL RAINFALL FORECAST IS FOR MOST
AREAS TO SEE AROUND AN INCH OR A LITTLE OVER BY WEDNESDAY MORNING.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* ANOTHER WINDOW FOR SHRA/TSRA MID/LATE AFTERNOON.
* LOW CHANCE FOR SOME ADDITIONAL SHRA/TSRA OVERNIGHT.
* WINDS TURNING WEST TONIGHT THEN NORTHWEST WEDNESDAY MORNING.
MDB
//DISCUSSION...UPDATED 18Z...
FOCUS REMAINS ON SHRA/TSRA POTENTIAL THROUGH THE AFTERNOON. AN
INITIAL ROUND OF SHRA/TSRA IS NOW CLEARING THE CHICAGO AREA
TERMINALS. ANOTHER BAND OF SHRA AND EMBEDDED TSRA IS STRETCHED
FROM RFD BACK TO FSW HAD BEEN BETTER ORGANIZED EARLIER IN THE DAY
BUT HAS BEGUN TO WANE OVER THE LAST HOUR. THIS AREA IS OUT AHEAD
OF AN UPPER TROUGH MOVING EASTWARD ACROSS EASTERN IOWA. A MORE
FAVORABLE AIRMASS IS IN PLACE ACROSS WEST CENTRAL ILLINOIS AND IT
MAY BE THAT DEVELOPMENT INCREASES IN THIS AREA WHICH MAY LARGELY
STAY SOUTH OF THE TERMINALS. HOWEVER...WITH SHRA/TSRA STILL ON
RADAR WILL CONTINUE TO BRING IT ACROSS THE TERMINALS THROUGH
MID/LATE AFTERNOON AND THERE IS STILL SOME POTENTIAL FOR RENEWED
DEVELOPMENT AS THE UPPER TROUGH APPROACHES. TOUGH CALL AND MAY
NEED TO DOWNPLAY THE POTENTIAL SLIGHTLY IN THE NEXT FEW HOURS.
ONCE THE WAVE PASSES LATE THIS AFTERNOON THERE LOOKS TO BE LITTLE
FOCUS FOR NEW DEVELOPMENT THROUGH THE EVENING SO WILL KEEP THE
TAFS DRY THOUGH A LOW CHANCE DOES EXIST FOR SOME SPOTTY
DEVELOPMENT GIVEN THE UNSTABLE AIRMASS. ANOTHER WAVE CROSSES THE
AREA OVERNIGHT BUT THE LOW AND MID LEVELS WILL BE DRIER SO CHANCES
FOR SHRA/TSRA WILL BE LOW. WINDS OVER THE NEXT FEW HOURS WILL
LIKELY BE SOMEWHAT VARIABLE BETWEEN SOUTH AND WEST THANKS TO THE
SHRA/TSRA BUT EXPECT THAT ONCE THE CURRENT ACTIVITY EXITS THE
CHICAGO/NW INDIANA AREA WINDS WILL TURN MORE SOUTHERLY BEFORE
GOING BACK TO WEST-SOUTHWEST LATER TODAY. A FRONT WILL CROSS THE
AREA WEDNESDAY MORNING SHIFTING WINDS TO THE NORTHWEST. SOME MVFR
STRATOCU IS EXPECTED DURING THE MORNING BUT WOULD LIKELY LIFT TO
VFR AND DIMINISH IN COVERAGE INTO THE AFTERNOON.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM-HIGH CONFIDENCE IN AT LEAST SOME SHRA/TSRA AFFECTING THE
TERMINALS MID/LATE AFTERNOON...MEDIUM-HIGH CONFIDENCE IN TIMING
...LOW-MEDIUM CONFIDENCE IN COVERAGE.
* MEDIUM CONFIDENCE THAT SHRA/TSRA POTENTIAL OVERNIGHT IS LOW.
* HIGH CONFIDENCE IN OVERALL WIND TRENDS BUT COULD BE BRIEFLY
AFFECTED BY ANY SHRA/TSRA ACTIVITY.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...VFR.
THURSDAY...VFR.
FRIDAY...VFR.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...VFR.
RODRIGUEZ
&&
.MARINE...
427 AM CDT
MAIN FORECAST CONCERN IN THE NEAR TERM IS FOR AREAS ACROSS THE
NORTHERN TWO THIRDS OF THE LAKE...WHERE DENSE FOG HAS SETTLED IN.
EXPECT THIS FOG TO PERSIST AT LEAST THROUGH THE AFTERNOON WITH
CURRENT THINKING THAT THIS FOG WILL CHURN UP WITH APPROACHING
PRECIP. ALTHOUGH CONFIDENCE IS LOW...AND ITS POSSIBLE THE CURRENT
DENSE FOG ADVISORY IN PLACE THROUGH THE AFTERNOON COULD NEED TO BE
EXTENDED THROUGH THE EVENING. THERE IS ALSO POTENTIAL FOR THE MORE
DENSE FOG TO PUSH FURTHER DOWN THE LAKE EARLY THIS
MORNING...BEFORE WINDS BEGIN TO SHIFT AND BRING A STOP TO THIS
SOUTHWARD MOVING AREA OF FOG.
CURRENT LIGHT NORTHERLY WINDS IN PLACE ACROSS THE LAKE WILL TURN
MORE SOUTHERLY THROUGHOUT TODAY AS THE NEXT SYSTEM APPROACHES FROM
THE WEST. AS THIS SYSTEM THEN PROGRESSES ACROSS THE LAKE
TONIGHT...EXPECT SOUTHWEST WINDS TO BECOME MORE WESTERLY WHILE
INCREASING MORE TOWARDS THE 10 TO 20 KT RANGE. THEN AS HIGH
PRESSURE SLOWLY BUILDS EAST TOWARDS THE LAKE...EXPECT GENERALLY
NORTHERLY WINDS THROUGH THE REST OF THE WORK WEEK.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ868-LMZ870-LMZ872-LMZ874
UNTIL 3 PM TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1145 AM CDT TUE JUL 9 2013
.DISCUSSION...
1144 AM CDT
FOR MORNING UPDATE...
NO SIGNIFICANT CHANGES TO GOING FORECAST FOR THE MOST PART OTHER
THAN REFINING POPS/WX AND TIMING OF WAVES OF SHOWERS/STORMS.
AN AREA OF SHOWERS AND THUNDERSTORMS WILL CONTINUE TO SPREAD EAST
ACROSS THE AREA THROUGH MIDDAY AHEAD OF A MID-LEVEL SHORT WAVE
TROUGH APPROACHING THE MID/UPPER MISSISSIPPI VALLEY. AS EXPECTED...
RELATIVELY WEAK MID/UPPER LEVEL FLOW RESULTING IN WEAK BULK SHEAR
MAGNITUDE...WITH LOOSELY ORGANIZED MCS PRESENTING MAINLY A LOCALLY
HEAVY RAIN THREAT GIVEN PWATS AROUND 2.00 INCHES.
THROUGH THIS AFTERNOON...MID-LEVEL TROUGH IS PROGGED TO MOVE EAST
ACROSS IL/WI...WITH ENHANCED VORTICITY/MCV OVER CENTRAL IA EXPECTED
TO HELP MAINTAIN AREA OF STORMS CURRENTLY OVER EASTERN/SOUTHEAST IA.
DESPITE IMPACT OF CLOUDS/SCATTERED PRECIP COVERAGE...THE COMBINATION
OF INCREASING MID-LEVEL FLOW AND DEEP SHEAR ALONG WITH DIURNAL
DESTABILIZATION IN WARM/MOIST AIR MASS WILL LIKELY RESULT IN AN
INCREASED COVERAGE AND ORGANIZATION TO STORMS DURING LATE AFTERNOON
AND EARLY EVENING HOURS...INCREASING SEVERE THREAT ALONG WITH
ONGOING HEAVY RAINFALL POTENTIAL. RECENT RUNS OF RAP/HRRR SEEM TO
HAVE A DECENT OVERALL HANDLE ON CURRENT ACTIVITY...AND SUPPORT THE
IDEA OF THE LINE OVER EASTERN IA MOVING ACROSS THE AREA FROM
MID-AFTERNOON INTO EARLY THIS EVENING.
RATZER
&&
.PREV DISCUSSION...
340 AM CDT
SEVERE WEATHER AND HEAVY RAIN POTENTIAL THROUGH TONIGHT WAS WHAT
MUCH OF THE ANALYSIS TIME WAS SPENT ON THIS MORNING. WHAT MAINLY
WAS TRYING TO DO WAS LOCK DOWN A TIMING FOR AN IMPROVED SEVERE
WEATHER THREAT /MID-AFTERNOON THROUGH EARLY OVERNIGHT THOUGH AIR
MASS CAN ALLOW FOR ISOLATED SEVERE ANYTIME/...AND WHAT MAIN
THREATS WOULD BE /WIND AND HEAVY RAIN/. OVERALL NO MAJOR CHANGES
MADE TO THE FORECAST...JUST INCREASING POPS IN THOSE MOST FAVORED
TIMES...RE-ORIENTING POPS SOME...AND REFINING RAINFALL AMOUNT
FORECASTS.
SYNOPSIS...A VERY SOUPY AIR MASS IS ENTRENCHED IN THE REGION
THIS MORNING WITH MID 70S DEW POINTS ACROSS THE FORECAST AREA AND
PWATS ON LAST EVES REGIONAL RAOBS AND EARLY MORNING OBJECTIVE
ANALYSIS BEING AROUND 2 INCHES. NUMEROUS SHORT WAVE IMPULSES...MANY
WITH ASSOCIATED CLUSTERS OF CONVECTION...ARE FOUND UPSTREAM ACROSS
THE HIGH PLAINS AND OVER THE WESTERN CORN BELT ON GOES WATER VAPOR
IMAGERY. THE PRIMARY UPPER LEVEL SHORT WAVE TROUGH WILL BE
DIGGING INTO EASTERN MT SOON AFTER DAYBREAK AND WILL BE THE
RESPONSIBLE PARTY FOR ENDING THIS MOIST AIR MASS...AT LEAST
TEMPORARILY BY LATER WED. AT THE SURFACE A FAIRLY DIFFUSE
GRADIENT EXISTS EARLY TODAY WITH A WEAK STATIONARY BOUNDARY NEAR
THE STATE LINE. THE WEAK FLOW HAS ALLOWED FOR LOW CLOUDS AND FOG
TO BE EXPANDING THEIR WAY SOUTHWARD DOWN LAKE MI AIDED BY AMBIENT
DEW POINTS EXCEEDING THE WATER TEMPS BY SEVERAL DEGREES. THE
PRIMARY SURFACE FRONT IS TAKING SHAPE ACROSS THE HIGH PLAINS AND
WILL DEVELOP INTO A COOL FRONT LATER TODAY AS SURFACE CYCLOGENESIS
OCCURS THROUGH NORTHERN MN INTO WESTERN ONTARIO BY THIS EVE. THIS
FRONT WILL MOVE INTO THE FORECAST AREA LATE TONIGHT INTO EARLY WED
MORNING. MULTIPLE ROUNDS OF CONVECTION ARE LIKELY AHEAD OF THIS.
MODEL PREFERENCE...THE RAP AND HRRR GUIDANCE HAVE A GOOD
REPRESENTATION OF ONGOING CONVECTION. THESE HAVE THE SUPPORT OF
SEVERAL OTHER CONVECTIVE ALLOWING MODELS AND HAVE BEEN GUIDED ON
THROUGH MID-AFTERNOON. AFTERWORDS HAVE LEANED TOWARD THE SLIGHTLY
SLOWER 09.00 NAM THAN GFS.
THIS MORNING...REMNANT MCV/SHORT WAVE ENTERING WESTERN IL EARLY
THIS MORNING HAS BEGUN TO INCREASE RADAR ECHOES ACROSS CENTRAL IL
AND THIS TREND IS LIKELY TO CONTINUE WITH SCATTERED CONVECTION
FAVORED DUE TO MODERATE TO HIGH ELEVATED INSTABILITY. NOT A
PARTICULARLY STRONG LOW-LEVEL JET OR ONE WITH HUGE MOISTURE
TRANSPORT THIS MORNING...DUE TO STILL BEING A GOOD DISTANCE AHEAD
OF MID-LEVEL HEIGHT FALLS. SO MORNING SCATTERED TO NUMEROUS
SHOWERS/STORMS ACROSS CENTRAL IL MAY STRUGGLE TO PROGRESS
NORTH/NORTHEAST AT LEAST AT ANY GOOD CLIP OF SPEED. THUS ROCKFORD
TO CHICAGO HAVE POPS ONLY AT THE CHANCE LEVEL...AND MORE SO BASED
ON ISOLATED CELLS DEVELOPING IN THE BROAD WAA AND HIGH PWAT
REGIME. WITH SUCH HIGH PWATS AS YESTERDAY MORNING SHOWED...LOCALLY
HEAVY RAINFALL WOULD BE THE PRIMARILY ASPECT TO KEEP AN EYE ON
WITH THESE MORNING AND EARLY AFTERNOON STORMS. AS FOR EARLY
MORNING FOG/STRATUS THAT HAS BEEN DEVELOPING IN PLACES...ONSHORE
FLOW MAY FAVOR PATCHES OF THIS TO CONTINUE THROUGH MID OR EVEN
LATE MORNING ACROSS NORTHEAST IL AND FAR NORTHWEST IN...STUNTING A
TEMPERATURE CLIMB INITIALLY. OTHERWISE THIS LOOKS LIKE IT SHOULD
BEGIN DISSIPATING/RETREATING NORTH AFTER THAT TIME.
CONFIDENCE...HIGH.
THIS AFTERNOON THROUGH TONIGHT...THE END OF THE RAP RUN AGREES
CLOSELY WITH THE NAM IN TAKING THE SHORT WAVES AND ASSOCIATED 500
AND 700MB SPEED MAXS ACROSS THE DAKOTAS AND NORTHERN NEBRASKA
EARLY THIS MORNING AND TRACKING THAT EAST INTO SOUTHERN WI AND
NORTHERN IL BY MID TO LATE AFTERNOON. ON THE SYNOPTIC SCALE AT
THAT TIME...THE LOW-LEVEL JET AND MOISTURE TRANSPORT WILL ALSO BE
ON THE EXPANSE FROM MO INTO EASTERN IA/WESTERN IL. MIXED LAYER
INSTABILITY WILL BE HIGH OVER THIS AREA INCLUDING THE WESTERN
FORECAST AREA GIVEN TEMPS IN THE UPPER 80S TO LOWER 90S. WHILE
SOME FORM OF MCS OR MULTIPLE CLUSTERS ARE PROBABLE TO BE MOVING
EASTWARD OVER SOUTHERN WI/FAR NORTHERN IL DURING THE AFTERNOON
WITH THE SHORT WAVES...DEVELOPMENT IS FAVORED TO WORK ITS WAY
SOUTH AND BACK TO THE SOUTHWEST FROM THERE IN THE MOIST UNSTABLE
AIR MASS DURING THE MID-AFTERNOON. DEEP LAYER SHEAR IS ANTICIPATED
TO BE INCREASING TO AROUND 30-35 KT BY LATE AFTERNOON WITH
ORGANIZED STORMS EXPECTED TO BE ALL WORKING THEIR WAY EASTWARD. AS
THE PRIMARY UPPER TROUGH APPROACHES THIS EVENING...LARGER SCALE
ASCENT AND FORCING IS LIKELY TO CONTINUE REGIONAL DEVELOPMENT OF
STORMS NEAR AND AHEAD OF THE SURFACE FRONT. SO WHILE THERE LOOKS
TO BE TWO PRIMARY FOCUSES FOR STORMS THIS AFTERNOON INTO
TONIGHT...THERE IS NOT REALLY ANTICIPATED TO BE MUCH OF A BREAK
AND THE HIGH PWAT AND UNSTABLE AIR SHOULD ALLOW FOR PLENTY OF
COVERAGE. THAT COVERAGE MAY INITIALLY BE A LITTLE LIMITED
DEPENDING ON DEBRIS CLOUD COVER BUT IS ANTICIPATED TO BE ITS
HIGHEST LATER THIS AFTERNOON THROUGH EARLY OVERNIGHT.
THE MOST FAVORED MODE FOR STORMS IS MULTICELL AND SEGMENTS
CAPABLE OF SCATTERED DAMAGING WINDS...ESPECIALLY AS THE STRONGER
MID-LEVEL JET OVERRIDES THE FRONT THIS EVENING INTO EARLY
OVERNIGHT. SOME DEVELOPMENT THIS AFTERNOON THROUGH MID-EVE HAS
THE POTENTIAL TO BE SUPERCELLULAR. THE LOW-LEVEL SHEAR IS FAIRLY
ANEMIC MUCH OF THIS AFTERNOON /AOB 10 KT/ BUT QUICKLY INCREASES
LATE INTO EARLY THIS EVE DUE TO THE DEEPENING LOW AND INCREASING
LLJ. THIS WILL HELP FAVOR COLD POOL SUSTAINABILITY AND DOES PRESENT
AT LEAST SOME TORNADO THREAT...ALTHOUGH IT LOOKS LIKE SURFACE
WINDS MAY BE BACKED MORE TO THE WEST OF THE FORECAST AREA
IMMEDIATELY AHEAD OF A SUBTLE SECONDARY SURFACE LOW MOVING UP THE
FRONT. SO THE PRIMARY THREAT WILL REMAIN WIND AND OF COURSE HEAVY
RAIN WITH EXTREMELY EFFICIENT RAIN PRODUCTION WILL OCCUR IN ANY
STORMS TODAY AND TONIGHT. EVEN THOUGH FORWARD PROPAGATION OF
STORMS SHOULD BE ON THE INCREASE TONIGHT...SO WILL DEEP MOISTURE
REPLENISHMENT AND SIMPLY PUT THE ABSOLUTE MOISTURE IS SO HIGH IT
WONT TAKE MUCH TO GET HIGH RAINFALL RATES SUCH AS WE SAW YESTERDAY
MORNING. THERE WILL LIKELY BE SWATHS OF RAINFALL IN EXCESS OF ONE
TO TWO INCHES ACROSS THE IMMEDIATE REGION...BUT WHERE EXACTLY
THEY OCCUR IS TOO CHALLENGING TO LOCK DOWN. DEBATED ON A FLASH
FLOOD WATCH BUT FEEL THE THREAT IS TOO LOCALIZED AT THIS TIME FOR
A WATCH.
CONFIDENCE...MEDIUM.
WEDNESDAY...ONGOING SCATTERED SHOWERS AND STORMS ARE POSSIBLE
ACROSS MAINLY THE SOUTHERN AND EASTERN FORECAST AREA IN THE
MORNING WITH STILL AT LEAST SOME HEAVY RAIN THREAT. WARM
850-925MB AIR BEHIND THE SURFACE WIND SHIFT WILL STILL FAVORED
HIGHS IN THE MID TO POSSIBLY EVEN UPPER 80S IN THE SOUTH. DRIER
AIR WILL GRADUALLY FILTER IN DURING THE LATER AFTERNOON AND NIGHT
PER GUIDANCE.
CONFIDENCE...HIGH.
THURSDAY THROUGH MONDAY...PRIMARILY DRY WEATHER IS EXPECTED OVER
THE AREA ALTHOUGH THE TREND IN BOTH THE EC AND GFS THEIR LAST
MULTIPLE RUNS SUPPORTS WARMER TEMPERATURES THIS WEEKEND WITH MID
AND MAYBE EVEN UPPER 80S SEEN. HAVE COLLABORATED AND LEANED TOWARD
THE WARMER MEX GUIDANCE. THE PATTERN STILL APPEARS BLOCKED JUST
WITH THE AREA MORE UNDER THE INFLUENCE OF THE UPPER RIDGE TO THE
WEST.
MTF
&&
.HYDROLOGY...
410 AM CDT
THE VERY MOIST AIR MASS WILL SUPPORT EFFICIENT RAINFALL PRODUCTION
FROM ANY THUNDERSTORMS TODAY AND TONIGHT. THIS MAY PRESENT FLASH
FLOODING ESPECIALLY ON THE LOCAL LEVEL AS OPPOSED TO ANY WIDESPREAD
THREAT. THAT AND THE FACT THERE IS NOT A GREAT SET UP FOR TRUE
TRAINING STORMS IS WHY NO FLASH FLOOD WATCH AT THIS TIME.
HOWEVER...IF ANY STORMS ARE IN A PARTICULARLY VULNERABLE
AREA...SUCH AS A METRO OR A QUICK-RESPONDING WATERSHED...IT COULD
BE TROUBLE. THESE TYPE OF HIGH RATES WERE ALREADY SEEN YESTERDAY
MORNING WITH A NARROW SWATH OF ONE AND A HALF TO ESTIMATED THREE
PLUS INCHES OF RAIN SEEN FROM RE-FIRING STORMS IN THE WEST CHICAGO
METRO. HIGH RESOLUTION MODEL GUIDANCE INDICATES SUCH SWATHS ARE
PROBABLE IN THE REGION THIS AFTERNOON INTO TONIGHT ALTHOUGH WHERE
IS STILL UNCERTAIN. THE GENERAL RAINFALL FORECAST IS FOR MOST
AREAS TO SEE AROUND AN INCH OR A LITTLE OVER BY WEDNESDAY MORNING.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* ONE BAND OF SCATTERED TSRA EXPECTED BETWEEN 17-19Z...VERY BRIEF
IFR VSBY POSSIBLE.
* NEXT ROUND OF TSRA EXPECTED LATE TOWARD 20/21Z FROM THE
WEST...BETTER ORGANIZATION AND LOWER VSBY IS MORE LIKELY WITH
THIS ROUND.
* SOME CHANCE OF ADDITIONAL SHRA/TSRA LATE TONIGHT OR EARLY
WEDNESDAY MORNING.
MDB
//DISCUSSION...UPDATED 16Z...
CONVECTIVE POTENTIAL STARTING TO BECOME A BIT MORE CLEAR. ONE
CLUSTER OF SHRA/TSRA CONTINUES TO APPROACH FROM THE WEST WITH
FLUCTUATIONS IN INTENSITY AND COVERAGE. INDIVIDUAL TS CELLS ARE
PRETTY SMALL BUT CONTINUE TO POP SO WILL CARRY VCTS AND A PERIOD
OF TEMPO TS AT THE TERMINALS OVER THE NEXT FEW HOURS...THOUGH
COVERAGE MAY BEGIN TO WANE. VERY BRIEF IFR VSBY IS POSSIBLE UNDER
THE HEAVIER CELLS. THE NEXT ROUND OF STORMS IS TAKING SHAPE ACROSS
EASTERN AND SOUTH CENTRAL IOWA WHICH WOULD ARRIVE IN THE AREA MID
TO LATE AFTERNOON. THERE SHOULD BE SHORT BREAK IN TS BEHIND THE
INITIAL AREA BEFORE THIS NEXT AREA ARRIVES. THIS SECOND AREA WILL
LIKELY BE MORE WIDESPREAD IN COVERAGE WITH LONGER PERIODS OF LOW
VISIBILITY POSSIBLE...ALONG WITH THE POTENTIAL FOR GUSTY WINDS.
THIS ALSO POINTS TO THE EVENING HOURS BEING QUIET SO WILL NEED TO
RE-EVALUATE SHRA/TSRA MENTION THEN.
MDB
FROM 12Z...
RELATIVELY QUIET ACROSS THE TERMINALS THIS MORNING WHILE SOME
FOG/HAZE REMAINS OVERHEAD...BUT WITH THE MORE DENSE FOG REMAINING
AWAY FROM THE TERMINALS AT THIS TIME. ANY FOG THIS MORNING SHOULD
QUICKLY DISSIPATE OVER THE NEXT HOUR WITH ANY THREAT OF LOWER
VIS/CEILINGS COMING SOUTH DOWN THE LAKE REMAINING LOW AT THIS
TIME. ALTHOUGH THIS AREA IS STILL SLOWLY MOVING SOUTH DOWN THE
LAKE...VEERING WINDS AND SHOULD HELP LIMIT THIS SOUTHWARD MOMENTUM
KEEPING THIS FOG NORTH OF THE TERMINALS. THEN SHIFT GEARS TO
REDEVELOPMENT OF SHOWERS/TS LATER THIS MORNING...AS PRECIP
DEVELOPS OUT AHEAD OF AN APPROACHING MID LEVEL DISTURBANCE. AS
THIS DISTURBANCE DRAWS NEAR...EXPECT CURRENT THUNDERSTORMS OVER
IOWA AS WELL AS OTHER DEVELOPMENT TO MOVE ACROSS THROUGH NORTHERN
ILLINOIS/NORTHWEST INDIANA BY MID DAY WITH SOME UPWARD GROWTH IN
COVERAGE AND INTENSITY EXPECTED INTO THE EARLY AFTERNOON. DO
EXPECT A BRIEF LULL IN THE ACTIVITY AFTER THIS INITIAL PRECIP
MOVES THROUGH...BUT WITH DEVELOPMENT STILL POSSIBLE GOING INTO THE
EARLY EVENING. STILL MONITORING THE POTENTIAL FOR A MORE
WIDESPREAD AREA OF THUNDERSTORMS TO MOVE ACROSS THE TERMINALS
LATER THIS EVENING AND OVERNIGHT. ALTHOUGH IT STILL SEEMS
FAVORABLE FOR THIS TO MOVE ACROSS THE TERMINALS...WILL NEED TO
MONITOR LATER TRENDS AFTER THIS INITIAL PRECIP THIS AFTERNOON
MOVES THROUGH.
WINDS REMAIN LIGHT/VARIABLE THIS MORNING BUT ANTICIPATE A TREND
TOWARDS AN EAST NORTHEAST WIND OVER THE NEXT SEVERAL HOURS. WINDS
ALONG THE LAKE ARE ALREADY THIS EASTERLY COMPONENT AND WITH THE
SUN RISING COINCIDING WITH A WEAK GRADIENT...FEEL THAT IT WONT
TAKE MUCH FOR THIS NORTHEAST WIND TO DEVELOP OVER ORD/MDW/GYY THIS
MORNING. THEN EXPECT A SLOW TREND TOWARDS THE SOUTHEAST AND
EVENTUALLY SOUTH THIS AFTERNOON/EVENING...BEFORE WINDS CONTINUE TO
VEER TO THE WEST OVERNIGHT.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH CONFIDENCE IN BAND OF SHRA/TSRA 17-19Z...MAY BE FAIRLY
SCATTERED THOUGH...HIGH CONFIDENCE THAT ANY IFR VSBY WOULD BE BRIEF.
* MEDIUM-HIGH CONFIDENCE IN ADDITIONAL ACTIVITY ARRIVING LATER
THIS AFTERNOON AND IT WOULD BE MORE WIDESPREAD AND
INTENSE...MEDIUM CONFIDENCE IN TIMING.
* LOW CONFIDENCE IN POTENTIAL FOR ADDITIONAL ACTIVITY
TONIGHT/WEDNESDAY MORNING.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...VFR.
THURSDAY...VFR.
FRIDAY...VFR.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...VFR.
RODRIGUEZ
&&
.MARINE...
427 AM CDT
MAIN FORECAST CONCERN IN THE NEAR TERM IS FOR AREAS ACROSS THE
NORTHERN TWO THIRDS OF THE LAKE...WHERE DENSE FOG HAS SETTLED IN.
EXPECT THIS FOG TO PERSIST AT LEAST THROUGH THE AFTERNOON WITH
CURRENT THINKING THAT THIS FOG WILL CHURN UP WITH APPROACHING
PRECIP. ALTHOUGH CONFIDENCE IS LOW...AND ITS POSSIBLE THE CURRENT
DENSE FOG ADVISORY IN PLACE THROUGH THE AFTERNOON COULD NEED TO BE
EXTENDED THROUGH THE EVENING. THERE IS ALSO POTENTIAL FOR THE MORE
DENSE FOG TO PUSH FURTHER DOWN THE LAKE EARLY THIS
MORNING...BEFORE WINDS BEGIN TO SHIFT AND BRING A STOP TO THIS
SOUTHWARD MOVING AREA OF FOG.
CURRENT LIGHT NORTHERLY WINDS IN PLACE ACROSS THE LAKE WILL TURN
MORE SOUTHERLY THROUGHOUT TODAY AS THE NEXT SYSTEM APPROACHES FROM
THE WEST. AS THIS SYSTEM THEN PROGRESSES ACROSS THE LAKE
TONIGHT...EXPECT SOUTHWEST WINDS TO BECOME MORE WESTERLY WHILE
INCREASING MORE TOWARDS THE 10 TO 20 KT RANGE. THEN AS HIGH
PRESSURE SLOWLY BUILDS EAST TOWARDS THE LAKE...EXPECT GENERALLY
NORTHERLY WINDS THROUGH THE REST OF THE WORK WEEK.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ868-LMZ870-LMZ872-LMZ874
UNTIL 3 PM TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1115 AM CDT TUE JUL 9 2013
.DISCUSSION...
340 AM CDT
SEVERE WEATHER AND HEAVY RAIN POTENTIAL THROUGH TONIGHT WAS WHAT
MUCH OF THE ANALYSIS TIME WAS SPENT ON THIS MORNING. WHAT MAINLY
WAS TRYING TO DO WAS LOCK DOWN A TIMING FOR AN IMPROVED SEVERE
WEATHER THREAT /MID-AFTERNOON THROUGH EARLY OVERNIGHT THOUGH AIR
MASS CAN ALLOW FOR ISOLATED SEVERE ANYTIME/...AND WHAT MAIN
THREATS WOULD BE /WIND AND HEAVY RAIN/. OVERALL NO MAJOR CHANGES
MADE TO THE FORECAST...JUST INCREASING POPS IN THOSE MOST FAVORED
TIMES...RE-ORIENTING POPS SOME...AND REFINING RAINFALL AMOUNT
FORECASTS.
SYNOPSIS...A VERY SOUPY AIR MASS IS ENTRENCHED IN THE REGION
THIS MORNING WITH MID 70S DEW POINTS ACROSS THE FORECAST AREA AND
PWATS ON LAST EVES REGIONAL RAOBS AND EARLY MORNING OBJECTIVE
ANALYSIS BEING AROUND 2 INCHES. NUMEROUS SHORT WAVE IMPULSES...MANY
WITH ASSOCIATED CLUSTERS OF CONVECTION...ARE FOUND UPSTREAM ACROSS
THE HIGH PLAINS AND OVER THE WESTERN CORN BELT ON GOES WATER VAPOR
IMAGERY. THE PRIMARY UPPER LEVEL SHORT WAVE TROUGH WILL BE
DIGGING INTO EASTERN MT SOON AFTER DAYBREAK AND WILL BE THE
RESPONSIBLE PARTY FOR ENDING THIS MOIST AIR MASS...AT LEAST
TEMPORARILY BY LATER WED. AT THE SURFACE A FAIRLY DIFFUSE
GRADIENT EXISTS EARLY TODAY WITH A WEAK STATIONARY BOUNDARY NEAR
THE STATE LINE. THE WEAK FLOW HAS ALLOWED FOR LOW CLOUDS AND FOG
TO BE EXPANDING THEIR WAY SOUTHWARD DOWN LAKE MI AIDED BY AMBIENT
DEW POINTS EXCEEDING THE WATER TEMPS BY SEVERAL DEGREES. THE
PRIMARY SURFACE FRONT IS TAKING SHAPE ACROSS THE HIGH PLAINS AND
WILL DEVELOP INTO A COOL FRONT LATER TODAY AS SURFACE CYCLOGENESIS
OCCURS THROUGH NORTHERN MN INTO WESTERN ONTARIO BY THIS EVE. THIS
FRONT WILL MOVE INTO THE FORECAST AREA LATE TONIGHT INTO EARLY WED
MORNING. MULTIPLE ROUNDS OF CONVECTION ARE LIKELY AHEAD OF THIS.
MODEL PREFERENCE...THE RAP AND HRRR GUIDANCE HAVE A GOOD
REPRESENTATION OF ONGOING CONVECTION. THESE HAVE THE SUPPORT OF
SEVERAL OTHER CONVECTIVE ALLOWING MODELS AND HAVE BEEN GUIDED ON
THROUGH MID-AFTERNOON. AFTERWORDS HAVE LEANED TOWARD THE SLIGHTLY
SLOWER 09.00 NAM THAN GFS.
THIS MORNING...REMNANT MCV/SHORT WAVE ENTERING WESTERN IL EARLY
THIS MORNING HAS BEGUN TO INCREASE RADAR ECHOES ACROSS CENTRAL IL
AND THIS TREND IS LIKELY TO CONTINUE WITH SCATTERED CONVECTION
FAVORED DUE TO MODERATE TO HIGH ELEVATED INSTABILITY. NOT A
PARTICULARLY STRONG LOW-LEVEL JET OR ONE WITH HUGE MOISTURE
TRANSPORT THIS MORNING...DUE TO STILL BEING A GOOD DISTANCE AHEAD
OF MID-LEVEL HEIGHT FALLS. SO MORNING SCATTERED TO NUMEROUS
SHOWERS/STORMS ACROSS CENTRAL IL MAY STRUGGLE TO PROGRESS
NORTH/NORTHEAST AT LEAST AT ANY GOOD CLIP OF SPEED. THUS ROCKFORD
TO CHICAGO HAVE POPS ONLY AT THE CHANCE LEVEL...AND MORE SO BASED
ON ISOLATED CELLS DEVELOPING IN THE BROAD WAA AND HIGH PWAT
REGIME. WITH SUCH HIGH PWATS AS YESTERDAY MORNING SHOWED...LOCALLY
HEAVY RAINFALL WOULD BE THE PRIMARILY ASPECT TO KEEP AN EYE ON
WITH THESE MORNING AND EARLY AFTERNOON STORMS. AS FOR EARLY
MORNING FOG/STRATUS THAT HAS BEEN DEVELOPING IN PLACES...ONSHORE
FLOW MAY FAVOR PATCHES OF THIS TO CONTINUE THROUGH MID OR EVEN
LATE MORNING ACROSS NORTHEAST IL AND FAR NORTHWEST IN...STUNTING A
TEMPERATURE CLIMB INITIALLY. OTHERWISE THIS LOOKS LIKE IT SHOULD
BEGIN DISSIPATING/RETREATING NORTH AFTER THAT TIME.
CONFIDENCE...HIGH.
THIS AFTERNOON THROUGH TONIGHT...THE END OF THE RAP RUN AGREES
CLOSELY WITH THE NAM IN TAKING THE SHORT WAVES AND ASSOCIATED 500
AND 700MB SPEED MAXS ACROSS THE DAKOTAS AND NORTHERN NEBRASKA
EARLY THIS MORNING AND TRACKING THAT EAST INTO SOUTHERN WI AND
NORTHERN IL BY MID TO LATE AFTERNOON. ON THE SYNOPTIC SCALE AT
THAT TIME...THE LOW-LEVEL JET AND MOISTURE TRANSPORT WILL ALSO BE
ON THE EXPANSE FROM MO INTO EASTERN IA/WESTERN IL. MIXED LAYER
INSTABILITY WILL BE HIGH OVER THIS AREA INCLUDING THE WESTERN
FORECAST AREA GIVEN TEMPS IN THE UPPER 80S TO LOWER 90S. WHILE
SOME FORM OF MCS OR MULTIPLE CLUSTERS ARE PROBABLE TO BE MOVING
EASTWARD OVER SOUTHERN WI/FAR NORTHERN IL DURING THE AFTERNOON
WITH THE SHORT WAVES...DEVELOPMENT IS FAVORED TO WORK ITS WAY
SOUTH AND BACK TO THE SOUTHWEST FROM THERE IN THE MOIST UNSTABLE
AIR MASS DURING THE MID-AFTERNOON. DEEP LAYER SHEAR IS ANTICIPATED
TO BE INCREASING TO AROUND 30-35 KT BY LATE AFTERNOON WITH
ORGANIZED STORMS EXPECTED TO BE ALL WORKING THEIR WAY EASTWARD. AS
THE PRIMARY UPPER TROUGH APPROACHES THIS EVENING...LARGER SCALE
ASCENT AND FORCING IS LIKELY TO CONTINUE REGIONAL DEVELOPMENT OF
STORMS NEAR AND AHEAD OF THE SURFACE FRONT. SO WHILE THERE LOOKS
TO BE TWO PRIMARY FOCUSES FOR STORMS THIS AFTERNOON INTO
TONIGHT...THERE IS NOT REALLY ANTICIPATED TO BE MUCH OF A BREAK
AND THE HIGH PWAT AND UNSTABLE AIR SHOULD ALLOW FOR PLENTY OF
COVERAGE. THAT COVERAGE MAY INITIALLY BE A LITTLE LIMITED
DEPENDING ON DEBRIS CLOUD COVER BUT IS ANTICIPATED TO BE ITS
HIGHEST LATER THIS AFTERNOON THROUGH EARLY OVERNIGHT.
THE MOST FAVORED MODE FOR STORMS IS MULTICELL AND SEGMENTS
CAPABLE OF SCATTERED DAMAGING WINDS...ESPECIALLY AS THE STRONGER
MID-LEVEL JET OVERRIDES THE FRONT THIS EVENING INTO EARLY
OVERNIGHT. SOME DEVELOPMENT THIS AFTERNOON THROUGH MID-EVE HAS
THE POTENTIAL TO BE SUPERCELLULAR. THE LOW-LEVEL SHEAR IS FAIRLY
ANEMIC MUCH OF THIS AFTERNOON /AOB 10 KT/ BUT QUICKLY INCREASES
LATE INTO EARLY THIS EVE DUE TO THE DEEPENING LOW AND INCREASING
LLJ. THIS WILL HELP FAVOR COLD POOL SUSTAINABILITY AND DOES PRESENT
AT LEAST SOME TORNADO THREAT...ALTHOUGH IT LOOKS LIKE SURFACE
WINDS MAY BE BACKED MORE TO THE WEST OF THE FORECAST AREA
IMMEDIATELY AHEAD OF A SUBTLE SECONDARY SURFACE LOW MOVING UP THE
FRONT. SO THE PRIMARY THREAT WILL REMAIN WIND AND OF COURSE HEAVY
RAIN WITH EXTREMELY EFFICIENT RAIN PRODUCTION WILL OCCUR IN ANY
STORMS TODAY AND TONIGHT. EVEN THOUGH FORWARD PROPAGATION OF
STORMS SHOULD BE ON THE INCREASE TONIGHT...SO WILL DEEP MOISTURE
REPLENISHMENT AND SIMPLY PUT THE ABSOLUTE MOISTURE IS SO HIGH IT
WONT TAKE MUCH TO GET HIGH RAINFALL RATES SUCH AS WE SAW YESTERDAY
MORNING. THERE WILL LIKELY BE SWATHS OF RAINFALL IN EXCESS OF ONE
TO TWO INCHES ACROSS THE IMMEDIATE REGION...BUT WHERE EXACTLY
THEY OCCUR IS TOO CHALLENGING TO LOCK DOWN. DEBATED ON A FLASH
FLOOD WATCH BUT FEEL THE THREAT IS TOO LOCALIZED AT THIS TIME FOR
A WATCH.
CONFIDENCE...MEDIUM.
WEDNESDAY...ONGOING SCATTERED SHOWERS AND STORMS ARE POSSIBLE
ACROSS MAINLY THE SOUTHERN AND EASTERN FORECAST AREA IN THE
MORNING WITH STILL AT LEAST SOME HEAVY RAIN THREAT. WARM
850-925MB AIR BEHIND THE SURFACE WIND SHIFT WILL STILL FAVORED
HIGHS IN THE MID TO POSSIBLY EVEN UPPER 80S IN THE SOUTH. DRIER
AIR WILL GRADUALLY FILTER IN DURING THE LATER AFTERNOON AND NIGHT
PER GUIDANCE.
CONFIDENCE...HIGH.
THURSDAY THROUGH MONDAY...PRIMARILY DRY WEATHER IS EXPECTED OVER
THE AREA ALTHOUGH THE TREND IN BOTH THE EC AND GFS THEIR LAST
MULTIPLE RUNS SUPPORTS WARMER TEMPERATURES THIS WEEKEND WITH MID
AND MAYBE EVEN UPPER 80S SEEN. HAVE COLLABORATED AND LEANED TOWARD
THE WARMER MEX GUIDANCE. THE PATTERN STILL APPEARS BLOCKED JUST
WITH THE AREA MORE UNDER THE INFLUENCE OF THE UPPER RIDGE TO THE
WEST.
MTF
&&
.HYDROLOGY...
410 AM CDT
THE VERY MOIST AIR MASS WILL SUPPORT EFFICIENT RAINFALL PRODUCTION
FROM ANY THUNDERSTORMS TODAY AND TONIGHT. THIS MAY PRESENT FLASH
FLOODING ESPECIALLY ON THE LOCAL LEVEL AS OPPOSED TO ANY WIDESPREAD
THREAT. THAT AND THE FACT THERE IS NOT A GREAT SET UP FOR TRUE
TRAINING STORMS IS WHY NO FLASH FLOOD WATCH AT THIS TIME.
HOWEVER...IF ANY STORMS ARE IN A PARTICULARLY VULNERABLE
AREA...SUCH AS A METRO OR A QUICK-RESPONDING WATERSHED...IT COULD
BE TROUBLE. THESE TYPE OF HIGH RATES WERE ALREADY SEEN YESTERDAY
MORNING WITH A NARROW SWATH OF ONE AND A HALF TO ESTIMATED THREE
PLUS INCHES OF RAIN SEEN FROM RE-FIRING STORMS IN THE WEST CHICAGO
METRO. HIGH RESOLUTION MODEL GUIDANCE INDICATES SUCH SWATHS ARE
PROBABLE IN THE REGION THIS AFTERNOON INTO TONIGHT ALTHOUGH WHERE
IS STILL UNCERTAIN. THE GENERAL RAINFALL FORECAST IS FOR MOST
AREAS TO SEE AROUND AN INCH OR A LITTLE OVER BY WEDNESDAY MORNING.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* ONE BAND OF SCATTERED TSRA EXPECTED BETWEEN 17-19Z...VERY BRIEF
IFR VSBY POSSIBLE.
* NEXT ROUND OF TSRA EXPECTED LATE TOWARD 20/21Z FROM THE
WEST...BETTER ORGANIZATION AND LOWER VSBY IS MORE LIKELY WITH
THIS ROUND.
* SOME CHANCE OF ADDITIONAL SHRA/TSRA LATE TONIGHT OR EARLY
WEDNESDAY MORNING.
MDB
//DISCUSSION...UPDATED 16Z...
CONVECTIVE POTENTIAL STARTING TO BECOME A BIT MORE CLEAR. ONE
CLUSTER OF SHRA/TSRA CONTINUES TO APPROACH FROM THE WEST WITH
FLUCTUATIONS IN INTENSITY AND COVERAGE. INDIVIDUAL TS CELLS ARE
PRETTY SMALL BUT CONTINUE TO POP SO WILL CARRY VCTS AND A PERIOD
OF TEMPO TS AT THE TERMINALS OVER THE NEXT FEW HOURS...THOUGH
COVERAGE MAY BEGIN TO WANE. VERY BRIEF IFR VSBY IS POSSIBLE UNDER
THE HEAVIER CELLS. THE NEXT ROUND OF STORMS IS TAKING SHAPE ACROSS
EASTERN AND SOUTH CENTRAL IOWA WHICH WOULD ARRIVE IN THE AREA MID
TO LATE AFTERNOON. THERE SHOULD BE SHORT BREAK IN TS BEHIND THE
INITIAL AREA BEFORE THIS NEXT AREA ARRIVES. THIS SECOND AREA WILL
LIKELY BE MORE WIDESPREAD IN COVERAGE WITH LONGER PERIODS OF LOW
VISIBILITY POSSIBLE...ALONG WITH THE POTENTIAL FOR GUSTY WINDS.
THIS ALSO POINTS TO THE EVENING HOURS BEING QUIET SO WILL NEED TO
RE-EVALUATE SHRA/TSRA MENTION THEN.
MDB
FROM 12Z...
RELATIVELY QUIET ACROSS THE TERMINALS THIS MORNING WHILE SOME
FOG/HAZE REMAINS OVERHEAD...BUT WITH THE MORE DENSE FOG REMAINING
AWAY FROM THE TERMINALS AT THIS TIME. ANY FOG THIS MORNING SHOULD
QUICKLY DISSIPATE OVER THE NEXT HOUR WITH ANY THREAT OF LOWER
VIS/CEILINGS COMING SOUTH DOWN THE LAKE REMAINING LOW AT THIS
TIME. ALTHOUGH THIS AREA IS STILL SLOWLY MOVING SOUTH DOWN THE
LAKE...VEERING WINDS AND SHOULD HELP LIMIT THIS SOUTHWARD MOMENTUM
KEEPING THIS FOG NORTH OF THE TERMINALS. THEN SHIFT GEARS TO
REDEVELOPMENT OF SHOWERS/TS LATER THIS MORNING...AS PRECIP
DEVELOPS OUT AHEAD OF AN APPROACHING MID LEVEL DISTURBANCE. AS
THIS DISTURBANCE DRAWS NEAR...EXPECT CURRENT THUNDERSTORMS OVER
IOWA AS WELL AS OTHER DEVELOPMENT TO MOVE ACROSS THROUGH NORTHERN
ILLINOIS/NORTHWEST INDIANA BY MID DAY WITH SOME UPWARD GROWTH IN
COVERAGE AND INTENSITY EXPECTED INTO THE EARLY AFTERNOON. DO
EXPECT A BRIEF LULL IN THE ACTIVITY AFTER THIS INITIAL PRECIP
MOVES THROUGH...BUT WITH DEVELOPMENT STILL POSSIBLE GOING INTO THE
EARLY EVENING. STILL MONITORING THE POTENTIAL FOR A MORE
WIDESPREAD AREA OF THUNDERSTORMS TO MOVE ACROSS THE TERMINALS
LATER THIS EVENING AND OVERNIGHT. ALTHOUGH IT STILL SEEMS
FAVORABLE FOR THIS TO MOVE ACROSS THE TERMINALS...WILL NEED TO
MONITOR LATER TRENDS AFTER THIS INITIAL PRECIP THIS AFTERNOON
MOVES THROUGH.
WINDS REMAIN LIGHT/VARIABLE THIS MORNING BUT ANTICIPATE A TREND
TOWARDS AN EAST NORTHEAST WIND OVER THE NEXT SEVERAL HOURS. WINDS
ALONG THE LAKE ARE ALREADY THIS EASTERLY COMPONENT AND WITH THE
SUN RISING COINCIDING WITH A WEAK GRADIENT...FEEL THAT IT WONT
TAKE MUCH FOR THIS NORTHEAST WIND TO DEVELOP OVER ORD/MDW/GYY THIS
MORNING. THEN EXPECT A SLOW TREND TOWARDS THE SOUTHEAST AND
EVENTUALLY SOUTH THIS AFTERNOON/EVENING...BEFORE WINDS CONTINUE TO
VEER TO THE WEST OVERNIGHT.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH CONFIDENCE IN BAND OF SHRA/TSRA 17-19Z...MAY BE FAIRLY
SCATTERED THOUGH...HIGH CONFIDENCE THAT ANY IFR VSBY WOULD BE BRIEF.
* MEDIUM-HIGH CONFIDENCE IN ADDITIONAL ACTIVITY ARRIVING LATER
THIS AFTERNOON AND IT WOULD BE MORE WIDESPREAD AND
INTENSE...MEDIUM CONFIDENCE IN TIMING.
* LOW CONFIDENCE IN POTENTIAL FOR ADDITIONAL ACTIVITY
TONIGHT/WEDNESDAY MORNING.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...VFR.
THURSDAY...VFR.
FRIDAY...VFR.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...VFR.
RODRIGUEZ
&&
.MARINE...
427 AM CDT
MAIN FORECAST CONCERN IN THE NEAR TERM IS FOR AREAS ACROSS THE
NORTHERN TWO THIRDS OF THE LAKE...WHERE DENSE FOG HAS SETTLED IN.
EXPECT THIS FOG TO PERSIST AT LEAST THROUGH THE AFTERNOON WITH
CURRENT THINKING THAT THIS FOG WILL CHURN UP WITH APPROACHING
PRECIP. ALTHOUGH CONFIDENCE IS LOW...AND ITS POSSIBLE THE CURRENT
DENSE FOG ADVISORY IN PLACE THROUGH THE AFTERNOON COULD NEED TO BE
EXTENDED THROUGH THE EVENING. THERE IS ALSO POTENTIAL FOR THE MORE
DENSE FOG TO PUSH FURTHER DOWN THE LAKE EARLY THIS
MORNING...BEFORE WINDS BEGIN TO SHIFT AND BRING A STOP TO THIS
SOUTHWARD MOVING AREA OF FOG.
CURRENT LIGHT NORTHERLY WINDS IN PLACE ACROSS THE LAKE WILL TURN
MORE SOUTHERLY THROUGHOUT TODAY AS THE NEXT SYSTEM APPROACHES FROM
THE WEST. AS THIS SYSTEM THEN PROGRESSES ACROSS THE LAKE
TONIGHT...EXPECT SOUTHWEST WINDS TO BECOME MORE WESTERLY WHILE
INCREASING MORE TOWARDS THE 10 TO 20 KT RANGE. THEN AS HIGH
PRESSURE SLOWLY BUILDS EAST TOWARDS THE LAKE...EXPECT GENERALLY
NORTHERLY WINDS THROUGH THE REST OF THE WORK WEEK.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ868-LMZ870-LMZ872-LMZ874
UNTIL 3 PM TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
926 AM CDT TUE JUL 9 2013
.DISCUSSION...
340 AM CDT
SEVERE WEATHER AND HEAVY RAIN POTENTIAL THROUGH TONIGHT WAS WHAT
MUCH OF THE ANALYSIS TIME WAS SPENT ON THIS MORNING. WHAT MAINLY
WAS TRYING TO DO WAS LOCK DOWN A TIMING FOR AN IMPROVED SEVERE
WEATHER THREAT /MID-AFTERNOON THROUGH EARLY OVERNIGHT THOUGH AIR
MASS CAN ALLOW FOR ISOLATED SEVERE ANYTIME/...AND WHAT MAIN
THREATS WOULD BE /WIND AND HEAVY RAIN/. OVERALL NO MAJOR CHANGES
MADE TO THE FORECAST...JUST INCREASING POPS IN THOSE MOST FAVORED
TIMES...RE-ORIENTING POPS SOME...AND REFINING RAINFALL AMOUNT
FORECASTS.
SYNOPSIS...A VERY SOUPY AIR MASS IS ENTRENCHED IN THE REGION
THIS MORNING WITH MID 70S DEW POINTS ACROSS THE FORECAST AREA AND
PWATS ON LAST EVES REGIONAL RAOBS AND EARLY MORNING OBJECTIVE
ANALYSIS BEING AROUND 2 INCHES. NUMEROUS SHORT WAVE IMPULSES...MANY
WITH ASSOCIATED CLUSTERS OF CONVECTION...ARE FOUND UPSTREAM ACROSS
THE HIGH PLAINS AND OVER THE WESTERN CORN BELT ON GOES WATER VAPOR
IMAGERY. THE PRIMARY UPPER LEVEL SHORT WAVE TROUGH WILL BE
DIGGING INTO EASTERN MT SOON AFTER DAYBREAK AND WILL BE THE
RESPONSIBLE PARTY FOR ENDING THIS MOIST AIR MASS...AT LEAST
TEMPORARILY BY LATER WED. AT THE SURFACE A FAIRLY DIFFUSE
GRADIENT EXISTS EARLY TODAY WITH A WEAK STATIONARY BOUNDARY NEAR
THE STATE LINE. THE WEAK FLOW HAS ALLOWED FOR LOW CLOUDS AND FOG
TO BE EXPANDING THEIR WAY SOUTHWARD DOWN LAKE MI AIDED BY AMBIENT
DEW POINTS EXCEEDING THE WATER TEMPS BY SEVERAL DEGREES. THE
PRIMARY SURFACE FRONT IS TAKING SHAPE ACROSS THE HIGH PLAINS AND
WILL DEVELOP INTO A COOL FRONT LATER TODAY AS SURFACE CYCLOGENESIS
OCCURS THROUGH NORTHERN MN INTO WESTERN ONTARIO BY THIS EVE. THIS
FRONT WILL MOVE INTO THE FORECAST AREA LATE TONIGHT INTO EARLY WED
MORNING. MULTIPLE ROUNDS OF CONVECTION ARE LIKELY AHEAD OF THIS.
MODEL PREFERENCE...THE RAP AND HRRR GUIDANCE HAVE A GOOD
REPRESENTATION OF ONGOING CONVECTION. THESE HAVE THE SUPPORT OF
SEVERAL OTHER CONVECTIVE ALLOWING MODELS AND HAVE BEEN GUIDED ON
THROUGH MID-AFTERNOON. AFTERWORDS HAVE LEANED TOWARD THE SLIGHTLY
SLOWER 09.00 NAM THAN GFS.
THIS MORNING...REMNANT MCV/SHORT WAVE ENTERING WESTERN IL EARLY
THIS MORNING HAS BEGUN TO INCREASE RADAR ECHOES ACROSS CENTRAL IL
AND THIS TREND IS LIKELY TO CONTINUE WITH SCATTERED CONVECTION
FAVORED DUE TO MODERATE TO HIGH ELEVATED INSTABILITY. NOT A
PARTICULARLY STRONG LOW-LEVEL JET OR ONE WITH HUGE MOISTURE
TRANSPORT THIS MORNING...DUE TO STILL BEING A GOOD DISTANCE AHEAD
OF MID-LEVEL HEIGHT FALLS. SO MORNING SCATTERED TO NUMEROUS
SHOWERS/STORMS ACROSS CENTRAL IL MAY STRUGGLE TO PROGRESS
NORTH/NORTHEAST AT LEAST AT ANY GOOD CLIP OF SPEED. THUS ROCKFORD
TO CHICAGO HAVE POPS ONLY AT THE CHANCE LEVEL...AND MORE SO BASED
ON ISOLATED CELLS DEVELOPING IN THE BROAD WAA AND HIGH PWAT
REGIME. WITH SUCH HIGH PWATS AS YESTERDAY MORNING SHOWED...LOCALLY
HEAVY RAINFALL WOULD BE THE PRIMARILY ASPECT TO KEEP AN EYE ON
WITH THESE MORNING AND EARLY AFTERNOON STORMS. AS FOR EARLY
MORNING FOG/STRATUS THAT HAS BEEN DEVELOPING IN PLACES...ONSHORE
FLOW MAY FAVOR PATCHES OF THIS TO CONTINUE THROUGH MID OR EVEN
LATE MORNING ACROSS NORTHEAST IL AND FAR NORTHWEST IN...STUNTING A
TEMPERATURE CLIMB INITIALLY. OTHERWISE THIS LOOKS LIKE IT SHOULD
BEGIN DISSIPATING/RETREATING NORTH AFTER THAT TIME.
CONFIDENCE...HIGH.
THIS AFTERNOON THROUGH TONIGHT...THE END OF THE RAP RUN AGREES
CLOSELY WITH THE NAM IN TAKING THE SHORT WAVES AND ASSOCIATED 500
AND 700MB SPEED MAXS ACROSS THE DAKOTAS AND NORTHERN NEBRASKA
EARLY THIS MORNING AND TRACKING THAT EAST INTO SOUTHERN WI AND
NORTHERN IL BY MID TO LATE AFTERNOON. ON THE SYNOPTIC SCALE AT
THAT TIME...THE LOW-LEVEL JET AND MOISTURE TRANSPORT WILL ALSO BE
ON THE EXPANSE FROM MO INTO EASTERN IA/WESTERN IL. MIXED LAYER
INSTABILITY WILL BE HIGH OVER THIS AREA INCLUDING THE WESTERN
FORECAST AREA GIVEN TEMPS IN THE UPPER 80S TO LOWER 90S. WHILE
SOME FORM OF MCS OR MULTIPLE CLUSTERS ARE PROBABLE TO BE MOVING
EASTWARD OVER SOUTHERN WI/FAR NORTHERN IL DURING THE AFTERNOON
WITH THE SHORT WAVES...DEVELOPMENT IS FAVORED TO WORK ITS WAY
SOUTH AND BACK TO THE SOUTHWEST FROM THERE IN THE MOIST UNSTABLE
AIR MASS DURING THE MID-AFTERNOON. DEEP LAYER SHEAR IS ANTICIPATED
TO BE INCREASING TO AROUND 30-35 KT BY LATE AFTERNOON WITH
ORGANIZED STORMS EXPECTED TO BE ALL WORKING THEIR WAY EASTWARD. AS
THE PRIMARY UPPER TROUGH APPROACHES THIS EVENING...LARGER SCALE
ASCENT AND FORCING IS LIKELY TO CONTINUE REGIONAL DEVELOPMENT OF
STORMS NEAR AND AHEAD OF THE SURFACE FRONT. SO WHILE THERE LOOKS
TO BE TWO PRIMARY FOCUSES FOR STORMS THIS AFTERNOON INTO
TONIGHT...THERE IS NOT REALLY ANTICIPATED TO BE MUCH OF A BREAK
AND THE HIGH PWAT AND UNSTABLE AIR SHOULD ALLOW FOR PLENTY OF
COVERAGE. THAT COVERAGE MAY INITIALLY BE A LITTLE LIMITED
DEPENDING ON DEBRIS CLOUD COVER BUT IS ANTICIPATED TO BE ITS
HIGHEST LATER THIS AFTERNOON THROUGH EARLY OVERNIGHT.
THE MOST FAVORED MODE FOR STORMS IS MULTICELL AND SEGMENTS
CAPABLE OF SCATTERED DAMAGING WINDS...ESPECIALLY AS THE STRONGER
MID-LEVEL JET OVERRIDES THE FRONT THIS EVENING INTO EARLY
OVERNIGHT. SOME DEVELOPMENT THIS AFTERNOON THROUGH MID-EVE HAS
THE POTENTIAL TO BE SUPERCELLULAR. THE LOW-LEVEL SHEAR IS FAIRLY
ANEMIC MUCH OF THIS AFTERNOON /AOB 10 KT/ BUT QUICKLY INCREASES
LATE INTO EARLY THIS EVE DUE TO THE DEEPENING LOW AND INCREASING
LLJ. THIS WILL HELP FAVOR COLD POOL SUSTAINABILITY AND DOES PRESENT
AT LEAST SOME TORNADO THREAT...ALTHOUGH IT LOOKS LIKE SURFACE
WINDS MAY BE BACKED MORE TO THE WEST OF THE FORECAST AREA
IMMEDIATELY AHEAD OF A SUBTLE SECONDARY SURFACE LOW MOVING UP THE
FRONT. SO THE PRIMARY THREAT WILL REMAIN WIND AND OF COURSE HEAVY
RAIN WITH EXTREMELY EFFICIENT RAIN PRODUCTION WILL OCCUR IN ANY
STORMS TODAY AND TONIGHT. EVEN THOUGH FORWARD PROPAGATION OF
STORMS SHOULD BE ON THE INCREASE TONIGHT...SO WILL DEEP MOISTURE
REPLENISHMENT AND SIMPLY PUT THE ABSOLUTE MOISTURE IS SO HIGH IT
WONT TAKE MUCH TO GET HIGH RAINFALL RATES SUCH AS WE SAW YESTERDAY
MORNING. THERE WILL LIKELY BE SWATHS OF RAINFALL IN EXCESS OF ONE
TO TWO INCHES ACROSS THE IMMEDIATE REGION...BUT WHERE EXACTLY
THEY OCCUR IS TOO CHALLENGING TO LOCK DOWN. DEBATED ON A FLASH
FLOOD WATCH BUT FEEL THE THREAT IS TOO LOCALIZED AT THIS TIME FOR
A WATCH.
CONFIDENCE...MEDIUM.
WEDNESDAY...ONGOING SCATTERED SHOWERS AND STORMS ARE POSSIBLE
ACROSS MAINLY THE SOUTHERN AND EASTERN FORECAST AREA IN THE
MORNING WITH STILL AT LEAST SOME HEAVY RAIN THREAT. WARM
850-925MB AIR BEHIND THE SURFACE WIND SHIFT WILL STILL FAVORED
HIGHS IN THE MID TO POSSIBLY EVEN UPPER 80S IN THE SOUTH. DRIER
AIR WILL GRADUALLY FILTER IN DURING THE LATER AFTERNOON AND NIGHT
PER GUIDANCE.
CONFIDENCE...HIGH.
THURSDAY THROUGH MONDAY...PRIMARILY DRY WEATHER IS EXPECTED OVER
THE AREA ALTHOUGH THE TREND IN BOTH THE EC AND GFS THEIR LAST
MULTIPLE RUNS SUPPORTS WARMER TEMPERATURES THIS WEEKEND WITH MID
AND MAYBE EVEN UPPER 80S SEEN. HAVE COLLABORATED AND LEANED TOWARD
THE WARMER MEX GUIDANCE. THE PATTERN STILL APPEARS BLOCKED JUST
WITH THE AREA MORE UNDER THE INFLUENCE OF THE UPPER RIDGE TO THE
WEST.
MTF
&&
.HYDROLOGY...
410 AM CDT
THE VERY MOIST AIR MASS WILL SUPPORT EFFICIENT RAINFALL PRODUCTION
FROM ANY THUNDERSTORMS TODAY AND TONIGHT. THIS MAY PRESENT FLASH
FLOODING ESPECIALLY ON THE LOCAL LEVEL AS OPPOSED TO ANY WIDESPREAD
THREAT. THAT AND THE FACT THERE IS NOT A GREAT SET UP FOR TRUE
TRAINING STORMS IS WHY NO FLASH FLOOD WATCH AT THIS TIME.
HOWEVER...IF ANY STORMS ARE IN A PARTICULARLY VULNERABLE
AREA...SUCH AS A METRO OR A QUICK-RESPONDING WATERSHED...IT COULD
BE TROUBLE. THESE TYPE OF HIGH RATES WERE ALREADY SEEN YESTERDAY
MORNING WITH A NARROW SWATH OF ONE AND A HALF TO ESTIMATED THREE
PLUS INCHES OF RAIN SEEN FROM RE-FIRING STORMS IN THE WEST CHICAGO
METRO. HIGH RESOLUTION MODEL GUIDANCE INDICATES SUCH SWATHS ARE
PROBABLE IN THE REGION THIS AFTERNOON INTO TONIGHT ALTHOUGH WHERE
IS STILL UNCERTAIN. THE GENERAL RAINFALL FORECAST IS FOR MOST
AREAS TO SEE AROUND AN INCH OR A LITTLE OVER BY WEDNESDAY MORNING.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* LIGHT SOUTHWEST WINDS EXPECTED TO CONTINUE WITH NORTHEAST WINDS
OFF THE LAKE EXPECTED TO STAY EAST OF THE TERMINALS THIS
MORNING.
* SHRA/TSRA CHANCES INCREASING FROM LATE MORNING THROUGH THE
AFTERNOON.
MDB
//DISCUSSION...UPDATED 14Z...
MADE SOME ADJUSTMENTS TO THE WINDS THIS MORNING TO BRING THEM
SOUTHWESTERLY AT ORD/MDW/GYY. A LIGHT NORTHEAST WIND IS OCCURRING
RIGHT ALONG THE LAKESHORE BUT HAS NOT MADE MUCH IF ANY PROGRESS
INLAND. WITH INCREASING CLOUD COVER SLOWING THE HEATING OVER LAND
COMPARED TO OVER THE LAKE...PRESSURE FALLS STARTING TO SPREAD IN
AND A SLOWLY INCREASING PRESSURE GRADIENT OPTED TO KEEP WINDS
LIGHT FROM THE SOUTHWEST. NEXT CONCERN IS SHOWERS AND
THUNDERSTORMS STRETCHING FROM NEAR VYS TO SFY TO PVB. THIS
ACTIVITY CONTINUES TO MOVE EASTWARD WITH COVERAGE INCREASING
SOMEWHAT. OTHERWISE SCATTERED VERY LIGHT SHOWERS DO RUN ALONG A
LINE FROM GYY WEST TO VYS. RFD WILL LIKELY HAVE PERIODIC TSRA
ARRIVE IN THE NEXT HOUR OR SO BUT COVERAGE TO THE EAST IS SOMEWHAT
IN QUESTION. IT APPEARS THAT THE INITIAL ACTIVITY WILL STAY JUST
SOUTH OF ORD/MDW AND GRAZE GYY BUT ACTIVITY MAY BUILD AND INCREASE
IN COVERAGE AS THE ENTIRE COMPLEX WORKS EAST. BARRING MUCH NEW
DEVELOPMENT EASTWARD THE CURRENT ACTIVITY WOULD LIKELY WORK INTO
THE CHI AREA TOWARD 17Z. MAY NEED TO SPEED THIS UP IN THE TAFS AS
THE TRENDS BECOME MORE CLEAR.
MDB
FROM 12Z...
RELATIVELY QUIET ACROSS THE TERMINALS THIS MORNING WHILE SOME
FOG/HAZE REMAINS OVERHEAD...BUT WITH THE MORE DENSE FOG REMAINING
AWAY FROM THE TERMINALS AT THIS TIME. ANY FOG THIS MORNING SHOULD
QUICKLY DISSIPATE OVER THE NEXT HOUR WITH ANY THREAT OF LOWER
VIS/CEILINGS COMING SOUTH DOWN THE LAKE REMAINING LOW AT THIS
TIME. ALTHOUGH THIS AREA IS STILL SLOWLY MOVING SOUTH DOWN THE
LAKE...VEERING WINDS AND SHOULD HELP LIMIT THIS SOUTHWARD MOMENTUM
KEEPING THIS FOG NORTH OF THE TERMINALS. THEN SHIFT GEARS TO
REDEVELOPMENT OF SHOWERS/TS LATER THIS MORNING...AS PRECIP
DEVELOPS OUT AHEAD OF AN APPROACHING MID LEVEL DISTURBANCE. AS
THIS DISTURBANCE DRAWS NEAR...EXPECT CURRENT THUNDERSTORMS OVER
IOWA AS WELL AS OTHER DEVELOPMENT TO MOVE ACROSS THROUGH NORTHERN
ILLINOIS/NORTHWEST INDIANA BY MID DAY WITH SOME UPWARD GROWTH IN
COVERAGE AND INTENSITY EXPECTED INTO THE EARLY AFTERNOON. DO
EXPECT A BRIEF LULL IN THE ACTIVITY AFTER THIS INITIAL PRECIP
MOVES THROUGH...BUT WITH DEVELOPMENT STILL POSSIBLE GOING INTO THE
EARLY EVENING. STILL MONITORING THE POTENTIAL FOR A MORE
WIDESPREAD AREA OF THUNDERSTORMS TO MOVE ACROSS THE TERMINALS
LATER THIS EVENING AND OVERNIGHT. ALTHOUGH IT STILL SEEMS
FAVORABLE FOR THIS TO MOVE ACROSS THE TERMINALS...WILL NEED TO
MONITOR LATER TRENDS AFTER THIS INITIAL PRECIP THIS AFTERNOON
MOVES THROUGH.
WINDS REMAIN LIGHT/VARIABLE THIS MORNING BUT ANTICIPATE A TREND
TOWARDS AN EAST NORTHEAST WIND OVER THE NEXT SEVERAL HOURS. WINDS
ALONG THE LAKE ARE ALREADY THIS EASTERLY COMPONENT AND WITH THE
SUN RISING COINCIDING WITH A WEAK GRADIENT...FEEL THAT IT WONT
TAKE MUCH FOR THIS NORTHEAST WIND TO DEVELOP OVER ORD/MDW/GYY THIS
MORNING. THEN EXPECT A SLOW TREND TOWARDS THE SOUTHEAST AND
EVENTUALLY SOUTH THIS AFTERNOON/EVENING...BEFORE WINDS CONTINUE TO
VEER TO THE WEST OVERNIGHT.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* MEDIUM-HIGH CONFIDENCE IN LIGHT SOUTHWEST WINDS PREVAILING
THROUGH THE MORNING.
* MEDIUM-HIGH CONFIDENCE IN SHRA/TSRA AFFECTING THE
TERMINALS...MEDIUM CONFIDENCE IN TIMING.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...VFR.
THURSDAY...VFR.
FRIDAY...VFR.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...VFR.
RODRIGUEZ
&&
.MARINE...
427 AM CDT
MAIN FORECAST CONCERN IN THE NEAR TERM IS FOR AREAS ACROSS THE
NORTHERN TWO THIRDS OF THE LAKE...WHERE DENSE FOG HAS SETTLED IN.
EXPECT THIS FOG TO PERSIST AT LEAST THROUGH THE AFTERNOON WITH
CURRENT THINKING THAT THIS FOG WILL CHURN UP WITH APPROACHING
PRECIP. ALTHOUGH CONFIDENCE IS LOW...AND ITS POSSIBLE THE CURRENT
DENSE FOG ADVISORY IN PLACE THROUGH THE AFTERNOON COULD NEED TO BE
EXTENDED THROUGH THE EVENING. THERE IS ALSO POTENTIAL FOR THE MORE
DENSE FOG TO PUSH FURTHER DOWN THE LAKE EARLY THIS
MORNING...BEFORE WINDS BEGIN TO SHIFT AND BRING A STOP TO THIS
SOUTHWARD MOVING AREA OF FOG.
CURRENT LIGHT NORTHERLY WINDS IN PLACE ACROSS THE LAKE WILL TURN
MORE SOUTHERLY THROUGHOUT TODAY AS THE NEXT SYSTEM APPROACHES FROM
THE WEST. AS THIS SYSTEM THEN PROGRESSES ACROSS THE LAKE
TONIGHT...EXPECT SOUTHWEST WINDS TO BECOME MORE WESTERLY WHILE
INCREASING MORE TOWARDS THE 10 TO 20 KT RANGE. THEN AS HIGH
PRESSURE SLOWLY BUILDS EAST TOWARDS THE LAKE...EXPECT GENERALLY
NORTHERLY WINDS THROUGH THE REST OF THE WORK WEEK.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ868-LMZ870-LMZ872-LMZ874
UNTIL 3 PM TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
705 AM CDT TUE JUL 9 2013
.DISCUSSION...
340 AM CDT
SEVERE WEATHER AND HEAVY RAIN POTENTIAL THROUGH TONIGHT WAS WHAT
MUCH OF THE ANALYSIS TIME WAS SPENT ON THIS MORNING. WHAT MAINLY
WAS TRYING TO DO WAS LOCK DOWN A TIMING FOR AN IMPROVED SEVERE
WEATHER THREAT /MID-AFTERNOON THROUGH EARLY OVERNIGHT THOUGH AIR
MASS CAN ALLOW FOR ISOLATED SEVERE ANYTIME/...AND WHAT MAIN
THREATS WOULD BE /WIND AND HEAVY RAIN/. OVERALL NO MAJOR CHANGES
MADE TO THE FORECAST...JUST INCREASING POPS IN THOSE MOST FAVORED
TIMES...RE-ORIENTING POPS SOME...AND REFINING RAINFALL AMOUNT
FORECASTS.
SYNOPSIS...A VERY SOUPY AIR MASS IS ENTRENCHED IN THE REGION
THIS MORNING WITH MID 70S DEW POINTS ACROSS THE FORECAST AREA AND
PWATS ON LAST EVES REGIONAL RAOBS AND EARLY MORNING OBJECTIVE
ANALYSIS BEING AROUND 2 INCHES. NUMEROUS SHORT WAVE IMPULSES...MANY
WITH ASSOCIATED CLUSTERS OF CONVECTION...ARE FOUND UPSTREAM ACROSS
THE HIGH PLAINS AND OVER THE WESTERN CORN BELT ON GOES WATER VAPOR
IMAGERY. THE PRIMARY UPPER LEVEL SHORT WAVE TROUGH WILL BE
DIGGING INTO EASTERN MT SOON AFTER DAYBREAK AND WILL BE THE
RESPONSIBLE PARTY FOR ENDING THIS MOIST AIR MASS...AT LEAST
TEMPORARILY BY LATER WED. AT THE SURFACE A FAIRLY DIFFUSE
GRADIENT EXISTS EARLY TODAY WITH A WEAK STATIONARY BOUNDARY NEAR
THE STATE LINE. THE WEAK FLOW HAS ALLOWED FOR LOW CLOUDS AND FOG
TO BE EXPANDING THEIR WAY SOUTHWARD DOWN LAKE MI AIDED BY AMBIENT
DEW POINTS EXCEEDING THE WATER TEMPS BY SEVERAL DEGREES. THE
PRIMARY SURFACE FRONT IS TAKING SHAPE ACROSS THE HIGH PLAINS AND
WILL DEVELOP INTO A COOL FRONT LATER TODAY AS SURFACE CYCLOGENESIS
OCCURS THROUGH NORTHERN MN INTO WESTERN ONTARIO BY THIS EVE. THIS
FRONT WILL MOVE INTO THE FORECAST AREA LATE TONIGHT INTO EARLY WED
MORNING. MULTIPLE ROUNDS OF CONVECTION ARE LIKELY AHEAD OF THIS.
MODEL PREFERENCE...THE RAP AND HRRR GUIDANCE HAVE A GOOD
REPRESENTATION OF ONGOING CONVECTION. THESE HAVE THE SUPPORT OF
SEVERAL OTHER CONVECTIVE ALLOWING MODELS AND HAVE BEEN GUIDED ON
THROUGH MID-AFTERNOON. AFTERWORDS HAVE LEANED TOWARD THE SLIGHTLY
SLOWER 09.00 NAM THAN GFS.
THIS MORNING...REMNANT MCV/SHORT WAVE ENTERING WESTERN IL EARLY
THIS MORNING HAS BEGUN TO INCREASE RADAR ECHOES ACROSS CENTRAL IL
AND THIS TREND IS LIKELY TO CONTINUE WITH SCATTERED CONVECTION
FAVORED DUE TO MODERATE TO HIGH ELEVATED INSTABILITY. NOT A
PARTICULARLY STRONG LOW-LEVEL JET OR ONE WITH HUGE MOISTURE
TRANSPORT THIS MORNING...DUE TO STILL BEING A GOOD DISTANCE AHEAD
OF MID-LEVEL HEIGHT FALLS. SO MORNING SCATTERED TO NUMEROUS
SHOWERS/STORMS ACROSS CENTRAL IL MAY STRUGGLE TO PROGRESS
NORTH/NORTHEAST AT LEAST AT ANY GOOD CLIP OF SPEED. THUS ROCKFORD
TO CHICAGO HAVE POPS ONLY AT THE CHANCE LEVEL...AND MORE SO BASED
ON ISOLATED CELLS DEVELOPING IN THE BROAD WAA AND HIGH PWAT
REGIME. WITH SUCH HIGH PWATS AS YESTERDAY MORNING SHOWED...LOCALLY
HEAVY RAINFALL WOULD BE THE PRIMARILY ASPECT TO KEEP AN EYE ON
WITH THESE MORNING AND EARLY AFTERNOON STORMS. AS FOR EARLY
MORNING FOG/STRATUS THAT HAS BEEN DEVELOPING IN PLACES...ONSHORE
FLOW MAY FAVOR PATCHES OF THIS TO CONTINUE THROUGH MID OR EVEN
LATE MORNING ACROSS NORTHEAST IL AND FAR NORTHWEST IN...STUNTING A
TEMPERATURE CLIMB INITIALLY. OTHERWISE THIS LOOKS LIKE IT SHOULD
BEGIN DISSIPATING/RETREATING NORTH AFTER THAT TIME.
CONFIDENCE...HIGH.
THIS AFTERNOON THROUGH TONIGHT...THE END OF THE RAP RUN AGREES
CLOSELY WITH THE NAM IN TAKING THE SHORT WAVES AND ASSOCIATED 500
AND 700MB SPEED MAXS ACROSS THE DAKOTAS AND NORTHERN NEBRASKA
EARLY THIS MORNING AND TRACKING THAT EAST INTO SOUTHERN WI AND
NORTHERN IL BY MID TO LATE AFTERNOON. ON THE SYNOPTIC SCALE AT
THAT TIME...THE LOW-LEVEL JET AND MOISTURE TRANSPORT WILL ALSO BE
ON THE EXPANSE FROM MO INTO EASTERN IA/WESTERN IL. MIXED LAYER
INSTABILITY WILL BE HIGH OVER THIS AREA INCLUDING THE WESTERN
FORECAST AREA GIVEN TEMPS IN THE UPPER 80S TO LOWER 90S. WHILE
SOME FORM OF MCS OR MULTIPLE CLUSTERS ARE PROBABLE TO BE MOVING
EASTWARD OVER SOUTHERN WI/FAR NORTHERN IL DURING THE AFTERNOON
WITH THE SHORT WAVES...DEVELOPMENT IS FAVORED TO WORK ITS WAY
SOUTH AND BACK TO THE SOUTHWEST FROM THERE IN THE MOIST UNSTABLE
AIR MASS DURING THE MID-AFTERNOON. DEEP LAYER SHEAR IS ANTICIPATED
TO BE INCREASING TO AROUND 30-35 KT BY LATE AFTERNOON WITH
ORGANIZED STORMS EXPECTED TO BE ALL WORKING THEIR WAY EASTWARD. AS
THE PRIMARY UPPER TROUGH APPROACHES THIS EVENING...LARGER SCALE
ASCENT AND FORCING IS LIKELY TO CONTINUE REGIONAL DEVELOPMENT OF
STORMS NEAR AND AHEAD OF THE SURFACE FRONT. SO WHILE THERE LOOKS
TO BE TWO PRIMARY FOCUSES FOR STORMS THIS AFTERNOON INTO
TONIGHT...THERE IS NOT REALLY ANTICIPATED TO BE MUCH OF A BREAK
AND THE HIGH PWAT AND UNSTABLE AIR SHOULD ALLOW FOR PLENTY OF
COVERAGE. THAT COVERAGE MAY INITIALLY BE A LITTLE LIMITED
DEPENDING ON DEBRIS CLOUD COVER BUT IS ANTICIPATED TO BE ITS
HIGHEST LATER THIS AFTERNOON THROUGH EARLY OVERNIGHT.
THE MOST FAVORED MODE FOR STORMS IS MULTICELL AND SEGMENTS
CAPABLE OF SCATTERED DAMAGING WINDS...ESPECIALLY AS THE STRONGER
MID-LEVEL JET OVERRIDES THE FRONT THIS EVENING INTO EARLY
OVERNIGHT. SOME DEVELOPMENT THIS AFTERNOON THROUGH MID-EVE HAS
THE POTENTIAL TO BE SUPERCELLULAR. THE LOW-LEVEL SHEAR IS FAIRLY
ANEMIC MUCH OF THIS AFTERNOON /AOB 10 KT/ BUT QUICKLY INCREASES
LATE INTO EARLY THIS EVE DUE TO THE DEEPENING LOW AND INCREASING
LLJ. THIS WILL HELP FAVOR COLD POOL SUSTAINABILITY AND DOES PRESENT
AT LEAST SOME TORNADO THREAT...ALTHOUGH IT LOOKS LIKE SURFACE
WINDS MAY BE BACKED MORE TO THE WEST OF THE FORECAST AREA
IMMEDIATELY AHEAD OF A SUBTLE SECONDARY SURFACE LOW MOVING UP THE
FRONT. SO THE PRIMARY THREAT WILL REMAIN WIND AND OF COURSE HEAVY
RAIN WITH EXTREMELY EFFICIENT RAIN PRODUCTION WILL OCCUR IN ANY
STORMS TODAY AND TONIGHT. EVEN THOUGH FORWARD PROPAGATION OF
STORMS SHOULD BE ON THE INCREASE TONIGHT...SO WILL DEEP MOISTURE
REPLENISHMENT AND SIMPLY PUT THE ABSOLUTE MOISTURE IS SO HIGH IT
WONT TAKE MUCH TO GET HIGH RAINFALL RATES SUCH AS WE SAW YESTERDAY
MORNING. THERE WILL LIKELY BE SWATHS OF RAINFALL IN EXCESS OF ONE
TO TWO INCHES ACROSS THE IMMEDIATE REGION...BUT WHERE EXACTLY
THEY OCCUR IS TOO CHALLENGING TO LOCK DOWN. DEBATED ON A FLASH
FLOOD WATCH BUT FEEL THE THREAT IS TOO LOCALIZED AT THIS TIME FOR
A WATCH.
CONFIDENCE...MEDIUM.
WEDNESDAY...ONGOING SCATTERED SHOWERS AND STORMS ARE POSSIBLE
ACROSS MAINLY THE SOUTHERN AND EASTERN FORECAST AREA IN THE
MORNING WITH STILL AT LEAST SOME HEAVY RAIN THREAT. WARM
850-925MB AIR BEHIND THE SURFACE WIND SHIFT WILL STILL FAVORED
HIGHS IN THE MID TO POSSIBLY EVEN UPPER 80S IN THE SOUTH. DRIER
AIR WILL GRADUALLY FILTER IN DURING THE LATER AFTERNOON AND NIGHT
PER GUIDANCE.
CONFIDENCE...HIGH.
THURSDAY THROUGH MONDAY...PRIMARILY DRY WEATHER IS EXPECTED OVER
THE AREA ALTHOUGH THE TREND IN BOTH THE EC AND GFS THEIR LAST
MULTIPLE RUNS SUPPORTS WARMER TEMPERATURES THIS WEEKEND WITH MID
AND MAYBE EVEN UPPER 80S SEEN. HAVE COLLABORATED AND LEANED TOWARD
THE WARMER MEX GUIDANCE. THE PATTERN STILL APPEARS BLOCKED JUST
WITH THE AREA MORE UNDER THE INFLUENCE OF THE UPPER RIDGE TO THE
WEST.
MTF
&&
.HYDROLOGY...
410 AM CDT
THE VERY MOIST AIR MASS WILL SUPPORT EFFICIENT RAINFALL PRODUCTION
FROM ANY THUNDERSTORMS TODAY AND TONIGHT. THIS MAY PRESENT FLASH
FLOODING ESPECIALLY ON THE LOCAL LEVEL AS OPPOSED TO ANY WIDESPREAD
THREAT. THAT AND THE FACT THERE IS NOT A GREAT SET UP FOR TRUE
TRAINING STORMS IS WHY NO FLASH FLOOD WATCH AT THIS TIME.
HOWEVER...IF ANY STORMS ARE IN A PARTICULARLY VULNERABLE
AREA...SUCH AS A METRO OR A QUICK-RESPONDING WATERSHED...IT COULD
BE TROUBLE. THESE TYPE OF HIGH RATES WERE ALREADY SEEN YESTERDAY
MORNING WITH A NARROW SWATH OF ONE AND A HALF TO ESTIMATED THREE
PLUS INCHES OF RAIN SEEN FROM RE-FIRING STORMS IN THE WEST CHICAGO
METRO. HIGH RESOLUTION MODEL GUIDANCE INDICATES SUCH SWATHS ARE
PROBABLE IN THE REGION THIS AFTERNOON INTO TONIGHT ALTHOUGH WHERE
IS STILL UNCERTAIN. THE GENERAL RAINFALL FORECAST IS FOR MOST
AREAS TO SEE AROUND AN INCH OR A LITTLE OVER BY WEDNESDAY MORNING.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* LINGERING FOG TO QUICKLY DISSIPATE THIS MORNING.
* AN INCREASE IN SHOWERS/TS EXPECTED BY MID DAY...AND THEN
EXPECTED TO INCREASE IN COVERAGE AND INTENSITY THROUGH THE
AFTERNOON.
* MORE WIDESPREAD SHOWERS/TS POSSIBLY TO MOVE ACROSS THE TERMINALS
ONCE AGAIN LATER THIS EVENING AND OVERNIGHT.
* VARIABLE WINDS THIS MORNING BECOMING LIGHT OUT OF THE EAST
NORTHEAST BY MID MORNING...AND THEN SLOWLY BECOMING MORE
SOUTHEAST THIS AFTERNOON AND EVENTUALLY SOUTHERLY THIS EVENING.
RODRIGUEZ
//DISCUSSION...UPDATED 12Z...
RELATIVELY QUIET ACROSS THE TERMINALS THIS MORNING WHILE SOME
FOG/HAZE REMAINS OVERHEAD...BUT WITH THE MORE DENSE FOG REMAINING
AWAY FROM THE TERMINALS AT THIS TIME. ANY FOG THIS MORNING SHOULD
QUICKLY DISSIPATE OVER THE NEXT HOUR WITH ANY THREAT OF LOWER
VIS/CEILINGS COMING SOUTH DOWN THE LAKE REMAINING LOW AT THIS
TIME. ALTHOUGH THIS AREA IS STILL SLOWLY MOVING SOUTH DOWN THE
LAKE...VEERING WINDS AND SHOULD HELP LIMIT THIS SOUTHWARD MOMENTUM
KEEPING THIS FOG NORTH OF THE TERMINALS. THEN SHIFT GEARS TO
REDEVELOPMENT OF SHOWERS/TS LATER THIS MORNING...AS PRECIP
DEVELOPS OUT AHEAD OF AN APPROACHING MID LEVEL DISTURBANCE. AS
THIS DISTURBANCE DRAWS NEAR...EXPECT CURRENT THUNDERSTORMS OVER
IOWA AS WELL AS OTHER DEVELOPMENT TO MOVE ACROSS THROUGH NORTHERN
ILLINOIS/NORTHWEST INDIANA BY MID DAY WITH SOME UPWARD GROWTH IN
COVERAGE AND INTENSITY EXPECTED INTO THE EARLY AFTERNOON. DO
EXPECT A BRIEF LULL IN THE ACTIVITY AFTER THIS INITIAL PRECIP
MOVES THROUGH...BUT WITH DEVELOPMENT STILL POSSIBLE GOING INTO THE
EARLY EVENING. STILL MONITORING THE POTENTIAL FOR A MORE
WIDESPREAD AREA OF THUNDERSTORMS TO MOVE ACROSS THE TERMINALS
LATER THIS EVENING AND OVERNIGHT. ALTHOUGH IT STILL SEEMS
FAVORABLE FOR THIS TO MOVE ACROSS THE TERMINALS...WILL NEED TO
MONITOR LATER TRENDS AFTER THIS INITIAL PRECIP THIS AFTERNOON
MOVES THROUGH.
WINDS REMAIN LIGHT/VARIABLE THIS MORNING BUT ANTICIPATE A TREND
TOWARDS AN EAST NORTHEAST WIND OVER THE NEXT SEVERAL HOURS. WINDS
ALONG THE LAKE ARE ALREADY THIS EASTERLY COMPONENT AND WITH THE
SUN RISING COINCIDING WITH A WEAK GRADIENT...FEEL THAT IT WONT
TAKE MUCH FOR THIS NORTHEAST WIND TO DEVELOP OVER ORD/MDW/GYY THIS
MORNING. THEN EXPECT A SLOW TREND TOWARDS THE SOUTHEAST AND
EVENTUALLY SOUTH THIS AFTERNOON/EVENING...BEFORE WINDS CONTINUE TO
VEER TO THE WEST OVERNIGHT.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* HIGH CONFIDENCE WITH FOG/VIS THIS MORNING.
* MEDIUM CONFIDENCE WITH SHOWERS/TS MID DAY THROUGH THE AFTERNOON.
* MEDIUM CONFIDENCE WITH SHOWERS/TS LATER THIS EVENING/OVERNIGHT.
* MEDIUM CONFIDENCE WITH WIND SPEED/DIRECTION.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...VFR.
THURSDAY...VFR.
FRIDAY...VFR.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...VFR.
RODRIGUEZ
&&
.MARINE...
427 AM CDT
MAIN FORECAST CONCERN IN THE NEAR TERM IS FOR AREAS ACROSS THE
NORTHERN TWO THIRDS OF THE LAKE...WHERE DENSE FOG HAS SETTLED IN.
EXPECT THIS FOG TO PERSIST AT LEAST THROUGH THE AFTERNOON WITH
CURRENT THINKING THAT THIS FOG WILL CHURN UP WITH APPROACHING
PRECIP. ALTHOUGH CONFIDENCE IS LOW...AND ITS POSSIBLE THE CURRENT
DENSE FOG ADVISORY IN PLACE THROUGH THE AFTERNOON COULD NEED TO BE
EXTENDED THROUGH THE EVENING. THERE IS ALSO POTENTIAL FOR THE MORE
DENSE FOG TO PUSH FURTHER DOWN THE LAKE EARLY THIS
MORNING...BEFORE WINDS BEGIN TO SHIFT AND BRING A STOP TO THIS
SOUTHWARD MOVING AREA OF FOG.
CURRENT LIGHT NORTHERLY WINDS IN PLACE ACROSS THE LAKE WILL TURN
MORE SOUTHERLY THROUGHOUT TODAY AS THE NEXT SYSTEM APPROACHES FROM
THE WEST. AS THIS SYSTEM THEN PROGRESSES ACROSS THE LAKE
TONIGHT...EXPECT SOUTHWEST WINDS TO BECOME MORE WESTERLY WHILE
INCREASING MORE TOWARDS THE 10 TO 20 KT RANGE. THEN AS HIGH
PRESSURE SLOWLY BUILDS EAST TOWARDS THE LAKE...EXPECT GENERALLY
NORTHERLY WINDS THROUGH THE REST OF THE WORK WEEK.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ868-LMZ870-LMZ872-LMZ874
UNTIL 3 PM TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
437 AM CDT TUE JUL 9 2013
.DISCUSSION...
340 AM CDT
SEVERE WEATHER AND HEAVY RAIN POTENTIAL THROUGH TONIGHT WAS WHAT
MUCH OF THE ANALYSIS TIME WAS SPENT ON THIS MORNING. WHAT MAINLY
WAS TRYING TO DO WAS LOCK DOWN A TIMING FOR AN IMPROVED SEVERE
WEATHER THREAT /MID-AFTERNOON THROUGH EARLY OVERNIGHT THOUGH AIR
MASS CAN ALLOW FOR ISOLATED SEVERE ANYTIME/...AND WHAT MAIN
THREATS WOULD BE /WIND AND HEAVY RAIN/. OVERALL NO MAJOR CHANGES
MADE TO THE FORECAST...JUST INCREASING POPS IN THOSE MOST FAVORED
TIMES...RE-ORIENTING POPS SOME...AND REFINING RAINFALL AMOUNT
FORECASTS.
SYNOPSIS...A VERY SOUPY AIR MASS IS ENTRENCHED IN THE REGION
THIS MORNING WITH MID 70S DEW POINTS ACROSS THE FORECAST AREA AND
PWATS ON LAST EVES REGIONAL RAOBS AND EARLY MORNING OBJECTIVE
ANALYSIS BEING AROUND 2 INCHES. NUMEROUS SHORT WAVE IMPULSES...MANY
WITH ASSOCIATED CLUSTERS OF CONVECTION...ARE FOUND UPSTREAM ACROSS
THE HIGH PLAINS AND OVER THE WESTERN CORN BELT ON GOES WATER VAPOR
IMAGERY. THE PRIMARY UPPER LEVEL SHORT WAVE TROUGH WILL BE
DIGGING INTO EASTERN MT SOON AFTER DAYBREAK AND WILL BE THE
RESPONSIBLE PARTY FOR ENDING THIS MOIST AIR MASS...AT LEAST
TEMPORARILY BY LATER WED. AT THE SURFACE A FAIRLY DIFFUSE
GRADIENT EXISTS EARLY TODAY WITH A WEAK STATIONARY BOUNDARY NEAR
THE STATE LINE. THE WEAK FLOW HAS ALLOWED FOR LOW CLOUDS AND FOG
TO BE EXPANDING THEIR WAY SOUTHWARD DOWN LAKE MI AIDED BY AMBIENT
DEW POINTS EXCEEDING THE WATER TEMPS BY SEVERAL DEGREES. THE
PRIMARY SURFACE FRONT IS TAKING SHAPE ACROSS THE HIGH PLAINS AND
WILL DEVELOP INTO A COOL FRONT LATER TODAY AS SURFACE CYCLOGENESIS
OCCURS THROUGH NORTHERN MN INTO WESTERN ONTARIO BY THIS EVE. THIS
FRONT WILL MOVE INTO THE FORECAST AREA LATE TONIGHT INTO EARLY WED
MORNING. MULTIPLE ROUNDS OF CONVECTION ARE LIKELY AHEAD OF THIS.
MODEL PREFERENCE...THE RAP AND HRRR GUIDANCE HAVE A GOOD
REPRESENTATION OF ONGOING CONVECTION. THESE HAVE THE SUPPORT OF
SEVERAL OTHER CONVECTIVE ALLOWING MODELS AND HAVE BEEN GUIDED ON
THROUGH MID-AFTERNOON. AFTERWORDS HAVE LEANED TOWARD THE SLIGHTLY
SLOWER 09.00 NAM THAN GFS.
THIS MORNING...REMNANT MCV/SHORT WAVE ENTERING WESTERN IL EARLY
THIS MORNING HAS BEGUN TO INCREASE RADAR ECHOES ACROSS CENTRAL IL
AND THIS TREND IS LIKELY TO CONTINUE WITH SCATTERED CONVECTION
FAVORED DUE TO MODERATE TO HIGH ELEVATED INSTABILITY. NOT A
PARTICULARLY STRONG LOW-LEVEL JET OR ONE WITH HUGE MOISTURE
TRANSPORT THIS MORNING...DUE TO STILL BEING A GOOD DISTANCE AHEAD
OF MID-LEVEL HEIGHT FALLS. SO MORNING SCATTERED TO NUMEROUS
SHOWERS/STORMS ACROSS CENTRAL IL MAY STRUGGLE TO PROGRESS
NORTH/NORTHEAST AT LEAST AT ANY GOOD CLIP OF SPEED. THUS ROCKFORD
TO CHICAGO HAVE POPS ONLY AT THE CHANCE LEVEL...AND MORE SO BASED
ON ISOLATED CELLS DEVELOPING IN THE BROAD WAA AND HIGH PWAT
REGIME. WITH SUCH HIGH PWATS AS YESTERDAY MORNING SHOWED...LOCALLY
HEAVY RAINFALL WOULD BE THE PRIMARILY ASPECT TO KEEP AN EYE ON
WITH THESE MORNING AND EARLY AFTERNOON STORMS. AS FOR EARLY
MORNING FOG/STRATUS THAT HAS BEEN DEVELOPING IN PLACES...ONSHORE
FLOW MAY FAVOR PATCHES OF THIS TO CONTINUE THROUGH MID OR EVEN
LATE MORNING ACROSS NORTHEAST IL AND FAR NORTHWEST IN...STUNTING A
TEMPERATURE CLIMB INITIALLY. OTHERWISE THIS LOOKS LIKE IT SHOULD
BEGIN DISSIPATING/RETREATING NORTH AFTER THAT TIME.
CONFIDENCE...HIGH.
THIS AFTERNOON THROUGH TONIGHT...THE END OF THE RAP RUN AGREES
CLOSELY WITH THE NAM IN TAKING THE SHORT WAVES AND ASSOCIATED 500
AND 700MB SPEED MAXS ACROSS THE DAKOTAS AND NORTHERN NEBRASKA
EARLY THIS MORNING AND TRACKING THAT EAST INTO SOUTHERN WI AND
NORTHERN IL BY MID TO LATE AFTERNOON. ON THE SYNOPTIC SCALE AT
THAT TIME...THE LOW-LEVEL JET AND MOISTURE TRANSPORT WILL ALSO BE
ON THE EXPANSE FROM MO INTO EASTERN IA/WESTERN IL. MIXED LAYER
INSTABILITY WILL BE HIGH OVER THIS AREA INCLUDING THE WESTERN
FORECAST AREA GIVEN TEMPS IN THE UPPER 80S TO LOWER 90S. WHILE
SOME FORM OF MCS OR MULTIPLE CLUSTERS ARE PROBABLE TO BE MOVING
EASTWARD OVER SOUTHERN WI/FAR NORTHERN IL DURING THE AFTERNOON
WITH THE SHORT WAVES...DEVELOPMENT IS FAVORED TO WORK ITS WAY
SOUTH AND BACK TO THE SOUTHWEST FROM THERE IN THE MOIST UNSTABLE
AIR MASS DURING THE MID-AFTERNOON. DEEP LAYER SHEAR IS ANTICIPATED
TO BE INCREASING TO AROUND 30-35 KT BY LATE AFTERNOON WITH
ORGANIZED STORMS EXPECTED TO BE ALL WORKING THEIR WAY EASTWARD. AS
THE PRIMARY UPPER TROUGH APPROACHES THIS EVENING...LARGER SCALE
ASCENT AND FORCING IS LIKELY TO CONTINUE REGIONAL DEVELOPMENT OF
STORMS NEAR AND AHEAD OF THE SURFACE FRONT. SO WHILE THERE LOOKS
TO BE TWO PRIMARY FOCUSES FOR STORMS THIS AFTERNOON INTO
TONIGHT...THERE IS NOT REALLY ANTICIPATED TO BE MUCH OF A BREAK
AND THE HIGH PWAT AND UNSTABLE AIR SHOULD ALLOW FOR PLENTY OF
COVERAGE. THAT COVERAGE MAY INITIALLY BE A LITTLE LIMITED
DEPENDING ON DEBRIS CLOUD COVER BUT IS ANTICIPATED TO BE ITS
HIGHEST LATER THIS AFTERNOON THROUGH EARLY OVERNIGHT.
THE MOST FAVORED MODE FOR STORMS IS MULTICELL AND SEGMENTS
CAPABLE OF SCATTERED DAMAGING WINDS...ESPECIALLY AS THE STRONGER
MID-LEVEL JET OVERRIDES THE FRONT THIS EVENING INTO EARLY
OVERNIGHT. SOME DEVELOPMENT THIS AFTERNOON THROUGH MID-EVE HAS
THE POTENTIAL TO BE SUPERCELLULAR. THE LOW-LEVEL SHEAR IS FAIRLY
ANEMIC MUCH OF THIS AFTERNOON /AOB 10 KT/ BUT QUICKLY INCREASES
LATE INTO EARLY THIS EVE DUE TO THE DEEPENING LOW AND INCREASING
LLJ. THIS WILL HELP FAVOR COLD POOL SUSTAINABILITY AND DOES PRESENT
AT LEAST SOME TORNADO THREAT...ALTHOUGH IT LOOKS LIKE SURFACE
WINDS MAY BE BACKED MORE TO THE WEST OF THE FORECAST AREA
IMMEDIATELY AHEAD OF A SUBTLE SECONDARY SURFACE LOW MOVING UP THE
FRONT. SO THE PRIMARY THREAT WILL REMAIN WIND AND OF COURSE HEAVY
RAIN WITH EXTREMELY EFFICIENT RAIN PRODUCTION WILL OCCUR IN ANY
STORMS TODAY AND TONIGHT. EVEN THOUGH FORWARD PROPAGATION OF
STORMS SHOULD BE ON THE INCREASE TONIGHT...SO WILL DEEP MOISTURE
REPLENISHMENT AND SIMPLY PUT THE ABSOLUTE MOISTURE IS SO HIGH IT
WONT TAKE MUCH TO GET HIGH RAINFALL RATES SUCH AS WE SAW YESTERDAY
MORNING. THERE WILL LIKELY BE SWATHS OF RAINFALL IN EXCESS OF ONE
TO TWO INCHES ACROSS THE IMMEDIATE REGION...BUT WHERE EXACTLY
THEY OCCUR IS TOO CHALLENGING TO LOCK DOWN. DEBATED ON A FLASH
FLOOD WATCH BUT FEEL THE THREAT IS TOO LOCALIZED AT THIS TIME FOR
A WATCH.
CONFIDENCE...MEDIUM.
WEDNESDAY...ONGOING SCATTERED SHOWERS AND STORMS ARE POSSIBLE
ACROSS MAINLY THE SOUTHERN AND EASTERN FORECAST AREA IN THE
MORNING WITH STILL AT LEAST SOME HEAVY RAIN THREAT. WARM
850-925MB AIR BEHIND THE SURFACE WIND SHIFT WILL STILL FAVORED
HIGHS IN THE MID TO POSSIBLY EVEN UPPER 80S IN THE SOUTH. DRIER
AIR WILL GRADUALLY FILTER IN DURING THE LATER AFTERNOON AND NIGHT
PER GUIDANCE.
CONFIDENCE...HIGH.
THURSDAY THROUGH MONDAY...PRIMARILY DRY WEATHER IS EXPECTED OVER
THE AREA ALTHOUGH THE TREND IN BOTH THE EC AND GFS THEIR LAST
MULTIPLE RUNS SUPPORTS WARMER TEMPERATURES THIS WEEKEND WITH MID
AND MAYBE EVEN UPPER 80S SEEN. HAVE COLLABORATED AND LEANED TOWARD
THE WARMER MEX GUIDANCE. THE PATTERN STILL APPEARS BLOCKED JUST
WITH THE AREA MORE UNDER THE INFLUENCE OF THE UPPER RIDGE TO THE
WEST.
MTF
&&
.HYDROLOGY...
410 AM CDT
THE VERY MOIST AIR MASS WILL SUPPORT EFFICIENT RAINFALL PRODUCTION
FROM ANY THUNDERSTORMS TODAY AND TONIGHT. THIS MAY PRESENT FLASH
FLOODING ESPECIALLY ON THE LOCAL LEVEL AS OPPOSED TO ANY WIDESPREAD
THREAT. THAT AND THE FACT THERE IS NOT A GREAT SET UP FOR TRUE
TRAINING STORMS IS WHY NO FLASH FLOOD WATCH AT THIS TIME.
HOWEVER...IF ANY STORMS ARE IN A PARTICULARLY VULNERABLE
AREA...SUCH AS A METRO OR A QUICK-RESPONDING WATERSHED...IT COULD
BE TROUBLE. THESE TYPE OF HIGH RATES WERE ALREADY SEEN YESTERDAY
MORNING WITH A NARROW SWATH OF ONE AND A HALF TO ESTIMATED THREE
PLUS INCHES OF RAIN SEEN FROM RE-FIRING STORMS IN THE WEST CHICAGO
METRO. HIGH RESOLUTION MODEL GUIDANCE INDICATES SUCH SWATHS ARE
PROBABLE IN THE REGION THIS AFTERNOON INTO TONIGHT ALTHOUGH WHERE
IS STILL UNCERTAIN. THE GENERAL RAINFALL FORECAST IS FOR MOST
AREAS TO SEE AROUND AN INCH OR A LITTLE OVER BY WEDNESDAY MORNING.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* FOG WITH REDUCED VIS OF 4SM-6SM DEVELOPING EARLY THIS MORNING.
* SHOWERS WITH POSSIBLE TS REDEVELOPING LATER THIS MORNING AND
CONTINUING THROUGH LATE MORNING.
* REDEVELOPMENT OF SHOWERS/TS ONCE AGAIN LATER THIS AFTERNOON.
* MORE WIDESPREAD SHOWERS/TS EXPECTED TO MOVE ACROSS THE TERMINALS
LATER THIS EVENING AND OVERNIGHT.
* COMPLEX WIND FORECAST WITH VARIABLE/LIGHT WINDS BECOMING
NORTHEAST LATER THIS MORNING...THEN SHIFTING MORE SOUTHERLY
LATER THIS AFTERNOON AND EVENING.
RODRIGUEZ
//DISCUSSION...UPDATED 06Z...
A VERY COMPLEX FORECAST PERIOD FOR THE TERMINALS OVER THE NEXT 24
HOURS AS VARYING WEATHER CONDITIONS AT MULTIPLE TIMES COULD HAVE
IMPACTS ON THE TERMINALS. IN THE NEAR TERM...THE SHOWERS/TS WHICH
HAD DEVELOPED ACROSS NORTHEAST ILLINOIS AND OVER SOUTHERN LAKE
MICHIGAN HAVE SINCE DIMINISHED EARLY THIS MORNING...AND THINK ANY
FURTHER DEVELOPMENT SHOULD REMAIN VERY ISOLATED AND BRIEF OUTSIDE
OF THE TERMINALS. WITH EXPECTED CLEARING...LIGHT WINDS AND A VERY
MOIST ENVIRONMENT SHOULD SUPPORT FOG DEVELOPMENT OVER THE
TERMINALS THIS MORNING WITH VIS RESTRICTION EXPECTED. OUTSIDE OF
THIS DEVELOPMENT...A LIGHT NORTHERLY WIND OVER THE LAKE WITH LOW
CEILINGS AND VIS FURTHER NORTH TOWARDS THE MIDDLE PART OF THE LAKE
RAISES SOME CONCERNS FOR POTENTIAL LOWER CEILINGS AND FOG TO MOVE
ACROSS THE TERMINALS NEAR THE LAKE...ORD/MDW/GYY. EVEN IF THE
CLOUDS/FOG TO THE NORTH DONT QUITE MAKE IT THIS FAR SOUTH...COOLER
AIR MOVING INTO A VERY MOIST ENVIRONMENT COULD SUPPORT LOW
CLOUD/FOG DEVELOPMENT NEAR THE LAKE SHORE ANYWAYS. CONFIDENCE IS
LOW WITH REGARDS TO THE POTENTIAL BUT WILL NEED TO MONITOR THIS
AND ADJUST AS NEEDED.
EXPECT REDEVELOPMENT OF SHOWERS/TS LATER THIS MORNING AS ANOTHER
MID LEVEL DISTURBANCE APPROACHES FROM THE WEST...WITH THIS
SCATTERED DEVELOPMENT POSSIBLY CONTINUING THROUGH MID DAY.
ALTHOUGH SHOULD SEE A DIMINISHING TREND INTO THE EARLY
AFTERNOON...REDEVELOPMENT IN AND AROUND THE TERMINALS WILL ONCE
AGAIN BE POSSIBLE LATE THIS AFTERNOON THROUGH THE EARLY EVENING.
MORE WIDESPREAD SHOWERS/THUNDERSTORMS ARE EXPECTED TO MOVE ACROSS
THE TERMINALS LATE THIS EVENING AND OVERNIGHT BEFORE EXITING EARLY
WEDNESDAY MORNING.
THE WIND FORECAST IS RATHER COMPLEX AS A WEAK GRADIENT WITH
SEVERAL BOUNDARIES MOVING ACROSS THE AREA ARE IN PLACE. WITH THESE
FEATURES IN PLACE...WIND DIRECTION AND SPEED WILL LIKELY RANGE
SUBSTANTIALLY FROM TERMINAL TO THE OTHER. LIGHT AND VARIABLE WINDS
FOR ALL OF THE TERMINALS EARLY THIS MORNING WILL PICK UP LATER
THIS MORNING WITH RFD THE ONLY SITE OBSERVING A MORE SOUTHERLY
DIRECTION EARLY ON. THE OTHER SITES SHOULD HOLD ONTO A NORTHEAST
DIRECTION LATER THIS MORNING...LIGHT AT FIRST BUT PICKING UP IN
SPEEDS. THEN AS THE GRADIENT TIGHTENS OUT AHEAD OF AN APPROACHING
SYSTEM...DO EXPECT A TRANSITION TO MORE OF A SOUTHERLY DIRECTION
TO OCCUR LATER THIS AFTERNOON AND THEN CONTINUE INTO THE EVENING
HOURS.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* MEDIUM CONFIDENCE WITH FOG/REDUCED VIS.
* LOW MEDIUM CONFIDENCE WITH SHOWERS/TS LATER THIS MORNING.
* MEDIUM CONFIDENCE WITH SHOWERS/TS THIS AFTERNOON.
* MEDIUM CONFIDENCE WITH SHOWERS/TS LATER THIS EVENING/OVERNIGHT.
* LOW/MEDIUM CONFIDENCE ON WIND SPEED/DIRECTION.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
* WEDNESDAY...CHANCE OF TSRA...MAINLY IN THE MORNING.
* THURSDAY THROUGH SUNDAY...DRY/VFR.
&&
.MARINE...
427 AM CDT
MAIN FORECAST CONCERN IN THE NEAR TERM IS FOR AREAS ACROSS THE
NORTHERN TWO THIRDS OF THE LAKE...WHERE DENSE FOG HAS SETTLED IN.
EXPECT THIS FOG TO PERSIST AT LEAST THROUGH THE AFTERNOON WITH
CURRENT THINKING THAT THIS FOG WILL CHURN UP WITH APPROACHING
PRECIP. ALTHOUGH CONFIDENCE IS LOW...AND ITS POSSIBLE THE CURRENT
DENSE FOG ADVISORY IN PLACE THROUGH THE AFTERNOON COULD NEED TO BE
EXTENDED THROUGH THE EVENING. THERE IS ALSO POTENTIAL FOR THE MORE
DENSE FOG TO PUSH FURTHER DOWN THE LAKE EARLY THIS
MORNING...BEFORE WINDS BEGIN TO SHIFT AND BRING A STOP TO THIS
SOUTHWARD MOVING AREA OF FOG.
CURRENT LIGHT NORTHERLY WINDS IN PLACE ACROSS THE LAKE WILL TURN
MORE SOUTHERLY THROUGHOUT TODAY AS THE NEXT SYSTEM APPROACHES FROM
THE WEST. AS THIS SYSTEM THEN PROGRESSES ACROSS THE LAKE
TONIGHT...EXPECT SOUTHWEST WINDS TO BECOME MORE WESTERLY WHILE
INCREASING MORE TOWARDS THE 10 TO 20 KT RANGE. THEN AS HIGH
PRESSURE SLOWLY BUILDS EAST TOWARDS THE LAKE...EXPECT GENERALLY
NORTHERLY WINDS THROUGH THE REST OF THE WORK WEEK.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ868-LMZ870-LMZ872-LMZ874
UNTIL 3 PM TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
425 AM CDT TUE JUL 9 2013
.DISCUSSION...
340 AM CDT
SEVERE WEATHER AND HEAVY RAIN POTENTIAL THROUGH TONIGHT WAS WHAT
MUCH OF THE ANALYSIS TIME WAS SPENT ON THIS MORNING. WHAT MAINLY
WAS TRYING TO DO WAS LOCK DOWN A TIMING FOR AN IMPROVED SEVERE
WEATHER THREAT /MID-AFTERNOON THROUGH EARLY OVERNIGHT THOUGH AIR
MASS CAN ALLOW FOR ISOLATED SEVERE ANYTIME/...AND WHAT MAIN
THREATS WOULD BE /WIND AND HEAVY RAIN/. OVERALL NO MAJOR CHANGES
MADE TO THE FORECAST...JUST INCREASING POPS IN THOSE MOST FAVORED
TIMES...RE-ORIENTING POPS SOME...AND REFINING RAINFALL AMOUNT
FORECASTS.
SYNOPSIS...A VERY SOUPY AIR MASS IS ENTRENCHED IN THE REGION
THIS MORNING WITH MID 70S DEW POINTS ACROSS THE FORECAST AREA AND
PWATS ON LAST EVES REGIONAL RAOBS AND EARLY MORNING OBJECTIVE
ANALYSIS BEING AROUND 2 INCHES. NUMEROUS SHORT WAVE IMPULSES...MANY
WITH ASSOCIATED CLUSTERS OF CONVECTION...ARE FOUND UPSTREAM ACROSS
THE HIGH PLAINS AND OVER THE WESTERN CORN BELT ON GOES WATER VAPOR
IMAGERY. THE PRIMARY UPPER LEVEL SHORT WAVE TROUGH WILL BE
DIGGING INTO EASTERN MT SOON AFTER DAYBREAK AND WILL BE THE
RESPONSIBLE PARTY FOR ENDING THIS MOIST AIR MASS...AT LEAST
TEMPORARILY BY LATER WED. AT THE SURFACE A FAIRLY DIFFUSE
GRADIENT EXISTS EARLY TODAY WITH A WEAK STATIONARY BOUNDARY NEAR
THE STATE LINE. THE WEAK FLOW HAS ALLOWED FOR LOW CLOUDS AND FOG
TO BE EXPANDING THEIR WAY SOUTHWARD DOWN LAKE MI AIDED BY AMBIENT
DEW POINTS EXCEEDING THE WATER TEMPS BY SEVERAL DEGREES. THE
PRIMARY SURFACE FRONT IS TAKING SHAPE ACROSS THE HIGH PLAINS AND
WILL DEVELOP INTO A COOL FRONT LATER TODAY AS SURFACE CYCLOGENESIS
OCCURS THROUGH NORTHERN MN INTO WESTERN ONTARIO BY THIS EVE. THIS
FRONT WILL MOVE INTO THE FORECAST AREA LATE TONIGHT INTO EARLY WED
MORNING. MULTIPLE ROUNDS OF CONVECTION ARE LIKELY AHEAD OF THIS.
MODEL PREFERENCE...THE RAP AND HRRR GUIDANCE HAVE A GOOD
REPRESENTATION OF ONGOING CONVECTION. THESE HAVE THE SUPPORT OF
SEVERAL OTHER CONVECTIVE ALLOWING MODELS AND HAVE BEEN GUIDED ON
THROUGH MID-AFTERNOON. AFTERWORDS HAVE LEANED TOWARD THE SLIGHTLY
SLOWER 09.00 NAM THAN GFS.
THIS MORNING...REMNANT MCV/SHORT WAVE ENTERING WESTERN IL EARLY
THIS MORNING HAS BEGUN TO INCREASE RADAR ECHOES ACROSS CENTRAL IL
AND THIS TREND IS LIKELY TO CONTINUE WITH SCATTERED CONVECTION
FAVORED DUE TO MODERATE TO HIGH ELEVATED INSTABILITY. NOT A
PARTICULARLY STRONG LOW-LEVEL JET OR ONE WITH HUGE MOISTURE
TRANSPORT THIS MORNING...DUE TO STILL BEING A GOOD DISTANCE AHEAD
OF MID-LEVEL HEIGHT FALLS. SO MORNING SCATTERED TO NUMEROUS
SHOWERS/STORMS ACROSS CENTRAL IL MAY STRUGGLE TO PROGRESS
NORTH/NORTHEAST AT LEAST AT ANY GOOD CLIP OF SPEED. THUS ROCKFORD
TO CHICAGO HAVE POPS ONLY AT THE CHANCE LEVEL...AND MORE SO BASED
ON ISOLATED CELLS DEVELOPING IN THE BROAD WAA AND HIGH PWAT
REGIME. WITH SUCH HIGH PWATS AS YESTERDAY MORNING SHOWED...LOCALLY
HEAVY RAINFALL WOULD BE THE PRIMARILY ASPECT TO KEEP AN EYE ON
WITH THESE MORNING AND EARLY AFTERNOON STORMS. AS FOR EARLY
MORNING FOG/STRATUS THAT HAS BEEN DEVELOPING IN PLACES...ONSHORE
FLOW MAY FAVOR PATCHES OF THIS TO CONTINUE THROUGH MID OR EVEN
LATE MORNING ACROSS NORTHEAST IL AND FAR NORTHWEST IN...STUNTING A
TEMPERATURE CLIMB INITIALLY. OTHERWISE THIS LOOKS LIKE IT SHOULD
BEGIN DISSIPATING/RETREATING NORTH AFTER THAT TIME.
CONFIDENCE...HIGH.
THIS AFTERNOON THROUGH TONIGHT...THE END OF THE RAP RUN AGREES
CLOSELY WITH THE NAM IN TAKING THE SHORT WAVES AND ASSOCIATED 500
AND 700MB SPEED MAXS ACROSS THE DAKOTAS AND NORTHERN NEBRASKA
EARLY THIS MORNING AND TRACKING THAT EAST INTO SOUTHERN WI AND
NORTHERN IL BY MID TO LATE AFTERNOON. ON THE SYNOPTIC SCALE AT
THAT TIME...THE LOW-LEVEL JET AND MOISTURE TRANSPORT WILL ALSO BE
ON THE EXPANSE FROM MO INTO EASTERN IA/WESTERN IL. MIXED LAYER
INSTABILITY WILL BE HIGH OVER THIS AREA INCLUDING THE WESTERN
FORECAST AREA GIVEN TEMPS IN THE UPPER 80S TO LOWER 90S. WHILE
SOME FORM OF MCS OR MULTIPLE CLUSTERS ARE PROBABLE TO BE MOVING
EASTWARD OVER SOUTHERN WI/FAR NORTHERN IL DURING THE AFTERNOON
WITH THE SHORT WAVES...DEVELOPMENT IS FAVORED TO WORK ITS WAY
SOUTH AND BACK TO THE SOUTHWEST FROM THERE IN THE MOIST UNSTABLE
AIR MASS DURING THE MID-AFTERNOON. DEEP LAYER SHEAR IS ANTICIPATED
TO BE INCREASING TO AROUND 30-35 KT BY LATE AFTERNOON WITH
ORGANIZED STORMS EXPECTED TO BE ALL WORKING THEIR WAY EASTWARD. AS
THE PRIMARY UPPER TROUGH APPROACHES THIS EVENING...LARGER SCALE
ASCENT AND FORCING IS LIKELY TO CONTINUE REGIONAL DEVELOPMENT OF
STORMS NEAR AND AHEAD OF THE SURFACE FRONT. SO WHILE THERE LOOKS
TO BE TWO PRIMARY FOCUSES FOR STORMS THIS AFTERNOON INTO
TONIGHT...THERE IS NOT REALLY ANTICIPATED TO BE MUCH OF A BREAK
AND THE HIGH PWAT AND UNSTABLE AIR SHOULD ALLOW FOR PLENTY OF
COVERAGE. THAT COVERAGE MAY INITIALLY BE A LITTLE LIMITED
DEPENDING ON DEBRIS CLOUD COVER BUT IS ANTICIPATED TO BE ITS
HIGHEST LATER THIS AFTERNOON THROUGH EARLY OVERNIGHT.
THE MOST FAVORED MODE FOR STORMS IS MULTICELL AND SEGMENTS
CAPABLE OF SCATTERED DAMAGING WINDS...ESPECIALLY AS THE STRONGER
MID-LEVEL JET OVERRIDES THE FRONT THIS EVENING INTO EARLY
OVERNIGHT. SOME DEVELOPMENT THIS AFTERNOON THROUGH MID-EVE HAS
THE POTENTIAL TO BE SUPERCELLULAR. THE LOW-LEVEL SHEAR IS FAIRLY
ANEMIC MUCH OF THIS AFTERNOON /AOB 10 KT/ BUT QUICKLY INCREASES
LATE INTO EARLY THIS EVE DUE TO THE DEEPENING LOW AND INCREASING
LLJ. THIS WILL HELP FAVOR COLD POOL SUSTAINABILITY AND DOES PRESENT
AT LEAST SOME TORNADO THREAT...ALTHOUGH IT LOOKS LIKE SURFACE
WINDS MAY BE BACKED MORE TO THE WEST OF THE FORECAST AREA
IMMEDIATELY AHEAD OF A SUBTLE SECONDARY SURFACE LOW MOVING UP THE
FRONT. SO THE PRIMARY THREAT WILL REMAIN WIND AND OF COURSE HEAVY
RAIN WITH EXTREMELY EFFICIENT RAIN PRODUCTION WILL OCCUR IN ANY
STORMS TODAY AND TONIGHT. EVEN THOUGH FORWARD PROPAGATION OF
STORMS SHOULD BE ON THE INCREASE TONIGHT...SO WILL DEEP MOISTURE
REPLENISHMENT AND SIMPLY PUT THE ABSOLUTE MOISTURE IS SO HIGH IT
WONT TAKE MUCH TO GET HIGH RAINFALL RATES SUCH AS WE SAW YESTERDAY
MORNING. THERE WILL LIKELY BE SWATHS OF RAINFALL IN EXCESS OF ONE
TO TWO INCHES ACROSS THE IMMEDIATE REGION...BUT WHERE EXACTLY
THEY OCCUR IS TOO CHALLENGING TO LOCK DOWN. DEBATED ON A FLASH
FLOOD WATCH BUT FEEL THE THREAT IS TOO LOCALIZED AT THIS TIME FOR
A WATCH.
CONFIDENCE...MEDIUM.
WEDNESDAY...ONGOING SCATTERED SHOWERS AND STORMS ARE POSSIBLE
ACROSS MAINLY THE SOUTHERN AND EASTERN FORECAST AREA IN THE
MORNING WITH STILL AT LEAST SOME HEAVY RAIN THREAT. WARM
850-925MB AIR BEHIND THE SURFACE WIND SHIFT WILL STILL FAVORED
HIGHS IN THE MID TO POSSIBLY EVEN UPPER 80S IN THE SOUTH. DRIER
AIR WILL GRADUALLY FILTER IN DURING THE LATER AFTERNOON AND NIGHT
PER GUIDANCE.
CONFIDENCE...HIGH.
THURSDAY THROUGH MONDAY...PRIMARILY DRY WEATHER IS EXPECTED OVER
THE AREA ALTHOUGH THE TREND IN BOTH THE EC AND GFS THEIR LAST
MULTIPLE RUNS SUPPORTS WARMER TEMPERATURES THIS WEEKEND WITH MID
AND MAYBE EVEN UPPER 80S SEEN. HAVE COLLABORATED AND LEANED TOWARD
THE WARMER MEX GUIDANCE. THE PATTERN STILL APPEARS BLOCKED JUST
WITH THE AREA MORE UNDER THE INFLUENCE OF THE UPPER RIDGE TO THE
WEST.
MTF
&&
.HYDROLOGY...
410 AM CDT
THE VERY MOIST AIR MASS WILL SUPPORT EFFICIENT RAINFALL PRODUCTION
FROM ANY THUNDERSTORMS TODAY AND TONIGHT. THIS MAY PRESENT FLASH
FLOODING ESPECIALLY ON THE LOCAL LEVEL AS OPPOSED TO ANY WIDESPREAD
THREAT. THAT AND THE FACT THERE IS NOT A GREAT SET UP FOR TRUE
TRAINING STORMS IS WHY NO FLASH FLOOD WATCH AT THIS TIME.
HOWEVER...IF ANY STORMS ARE IN A PARTICULARLY VULNERABLE
AREA...SUCH AS A METRO OR A QUICK-RESPONDING WATERSHED...IT COULD
BE TROUBLE. THESE TYPE OF HIGH RATES WERE ALREADY SEEN YESTERDAY
MORNING WITH A NARROW SWATH OF ONE AND A HALF TO ESTIMATED THREE
PLUS INCHES OF RAIN SEEN FROM RE-FIRING STORMS IN THE WEST CHICAGO
METRO. HIGH RESOLUTION MODEL GUIDANCE INDICATES SUCH SWATHS ARE
PROBABLE IN THE REGION THIS AFTERNOON INTO TONIGHT ALTHOUGH WHERE
IS STILL UNCERTAIN. THE GENERAL RAINFALL FORECAST IS FOR MOST
AREAS TO SEE AROUND AN INCH OR A LITTLE OVER BY WEDNESDAY MORNING.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* FOG WITH REDUCED VIS OF 4SM-6SM DEVELOPING EARLY THIS MORNING.
* SHOWERS WITH POSSIBLE TS REDEVELOPING LATER THIS MORNING AND
CONTINUING THROUGH LATE MORNING.
* REDEVELOPMENT OF SHOWERS/TS ONCE AGAIN LATER THIS AFTERNOON.
* MORE WIDESPREAD SHOWERS/TS EXPECTED TO MOVE ACROSS THE TERMINALS
LATER THIS EVENING AND OVERNIGHT.
* COMPLEX WIND FORECAST WITH VARIABLE/LIGHT WINDS BECOMING
NORTHEAST LATER THIS MORNING...THEN SHIFTING MORE SOUTHERLY
LATER THIS AFTERNOON AND EVENING.
RODRIGUEZ
//DISCUSSION...UPDATED 06Z...
A VERY COMPLEX FORECAST PERIOD FOR THE TERMINALS OVER THE NEXT 24
HOURS AS VARYING WEATHER CONDITIONS AT MULTIPLE TIMES COULD HAVE
IMPACTS ON THE TERMINALS. IN THE NEAR TERM...THE SHOWERS/TS WHICH
HAD DEVELOPED ACROSS NORTHEAST ILLINOIS AND OVER SOUTHERN LAKE
MICHIGAN HAVE SINCE DIMINISHED EARLY THIS MORNING...AND THINK ANY
FURTHER DEVELOPMENT SHOULD REMAIN VERY ISOLATED AND BRIEF OUTSIDE
OF THE TERMINALS. WITH EXPECTED CLEARING...LIGHT WINDS AND A VERY
MOIST ENVIRONMENT SHOULD SUPPORT FOG DEVELOPMENT OVER THE
TERMINALS THIS MORNING WITH VIS RESTRICTION EXPECTED. OUTSIDE OF
THIS DEVELOPMENT...A LIGHT NORTHERLY WIND OVER THE LAKE WITH LOW
CEILINGS AND VIS FURTHER NORTH TOWARDS THE MIDDLE PART OF THE LAKE
RAISES SOME CONCERNS FOR POTENTIAL LOWER CEILINGS AND FOG TO MOVE
ACROSS THE TERMINALS NEAR THE LAKE...ORD/MDW/GYY. EVEN IF THE
CLOUDS/FOG TO THE NORTH DONT QUITE MAKE IT THIS FAR SOUTH...COOLER
AIR MOVING INTO A VERY MOIST ENVIRONMENT COULD SUPPORT LOW
CLOUD/FOG DEVELOPMENT NEAR THE LAKE SHORE ANYWAYS. CONFIDENCE IS
LOW WITH REGARDS TO THE POTENTIAL BUT WILL NEED TO MONITOR THIS
AND ADJUST AS NEEDED.
EXPECT REDEVELOPMENT OF SHOWERS/TS LATER THIS MORNING AS ANOTHER
MID LEVEL DISTURBANCE APPROACHES FROM THE WEST...WITH THIS
SCATTERED DEVELOPMENT POSSIBLY CONTINUING THROUGH MID DAY.
ALTHOUGH SHOULD SEE A DIMINISHING TREND INTO THE EARLY
AFTERNOON...REDEVELOPMENT IN AND AROUND THE TERMINALS WILL ONCE
AGAIN BE POSSIBLE LATE THIS AFTERNOON THROUGH THE EARLY EVENING.
MORE WIDESPREAD SHOWERS/THUNDERSTORMS ARE EXPECTED TO MOVE ACROSS
THE TERMINALS LATE THIS EVENING AND OVERNIGHT BEFORE EXITING EARLY
WEDNESDAY MORNING.
THE WIND FORECAST IS RATHER COMPLEX AS A WEAK GRADIENT WITH
SEVERAL BOUNDARIES MOVING ACROSS THE AREA ARE IN PLACE. WITH THESE
FEATURES IN PLACE...WIND DIRECTION AND SPEED WILL LIKELY RANGE
SUBSTANTIALLY FROM TERMINAL TO THE OTHER. LIGHT AND VARIABLE WINDS
FOR ALL OF THE TERMINALS EARLY THIS MORNING WILL PICK UP LATER
THIS MORNING WITH RFD THE ONLY SITE OBSERVING A MORE SOUTHERLY
DIRECTION EARLY ON. THE OTHER SITES SHOULD HOLD ONTO A NORTHEAST
DIRECTION LATER THIS MORNING...LIGHT AT FIRST BUT PICKING UP IN
SPEEDS. THEN AS THE GRADIENT TIGHTENS OUT AHEAD OF AN APPROACHING
SYSTEM...DO EXPECT A TRANSITION TO MORE OF A SOUTHERLY DIRECTION
TO OCCUR LATER THIS AFTERNOON AND THEN CONTINUE INTO THE EVENING
HOURS.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* MEDIUM CONFIDENCE WITH FOG/REDUCED VIS.
* LOW MEDIUM CONFIDENCE WITH SHOWERS/TS LATER THIS MORNING.
* MEDIUM CONFIDENCE WITH SHOWERS/TS THIS AFTERNOON.
* MEDIUM CONFIDENCE WITH SHOWERS/TS LATER THIS EVENING/OVERNIGHT.
* LOW/MEDIUM CONFIDENCE ON WIND SPEED/DIRECTION.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
* WEDNESDAY...CHANCE OF TSRA...MAINLY IN THE MORNING.
* THURSDAY THROUGH SUNDAY...DRY/VFR.
&&
.MARINE...
312 PM CDT
A WEAK LOW IS OVER SOUTHERN WISCONSIN AND IT WILL MOVE OVER THE LAKE
TONIGHT REACHING THE EASTERN GREAT LAKES BY MORNING BEFORE
DISSIPATING. WINDS WILL TURN NORTHEAST AND DIMINISH TO 10 KT OR
LESS BEHIND THE LOW. A LOW FORMS OVER THE CENTRAL PLAINS TONIGHT
AND WINDS VEER TO S TO SE AHEAD OF IT TOMORROW. S TO SW WINDS
INCREASE TO 20 KT TUESDAY NIGHT AND THEN BECOME W TO NW BEHIND THE
LOW WEDNESDAY MORNING. A HIGH FORMS OVER THE PLAINS WEDNESDAY AND
THEN MOVES OVER THE LAKE THURSDAY. WINDS BECOME LIGHT UNDER THE
HIGH AND THEN TURN S TO SE ON THE BACKSIDE OF THE HIGH FRIDAY
NIGHT. WHILE THE CENTER OF THE HIGH SHIFTS OVER NEW ENGLAND
SATURDAY...THE LAKE WILL STILL HAVE S TO SE FLOW THROUGH THE END OF
THE WEEKEND.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ868-LMZ870-LMZ872-LMZ874
UNTIL 3 PM TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
418 AM CDT TUE JUL 9 2013
.DISCUSSION...
340 AM CDT
SEVERE WEATHER AND HEAVY RAIN POTENTIAL THROUGH TONIGHT WAS WHAT
MUCH OF THE ANALYSIS TIME WAS SPENT ON THIS MORNING. WHAT MAINLY
WAS TRYING TO DO WAS LOCK DOWN A TIMING FOR AN IMPROVED SEVERE
WEATHER THREAT /MID-AFTERNOON THROUGH EARLY OVERNIGHT THOUGH AIR
MASS CAN ALLOW FOR ISOLATED SEVERE ANYTIME/...AND WHAT MAIN
THREATS WOULD BE /WIND AND HEAVY RAIN/. OVERALL NO MAJOR CHANGES
MADE TO THE FORECAST...JUST INCREASING POPS IN THOSE MOST FAVORED
TIMES...RE-ORIENTING POPS SOME...AND REFINING RAINFALL AMOUNT
FORECASTS.
SYNOPSIS...A VERY SOUPY AIR MASS IS ENTRENCHED IN THE REGION
THIS MORNING WITH MID 70S DEW POINTS ACROSS THE FORECAST AREA AND
PWATS ON LAST EVES REGIONAL RAOBS AND EARLY MORNING OBJECTIVE
ANALYSIS BEING AROUND 2 INCHES. NUMEROUS SHORT WAVE IMPULSES...MANY
WITH ASSOCIATED CLUSTERS OF CONVECTION...ARE FOUND UPSTREAM ACROSS
THE HIGH PLAINS AND OVER THE WESTERN CORN BELT ON GOES WATER VAPOR
IMAGERY. THE PRIMARY UPPER LEVEL SHORT WAVE TROUGH WILL BE
DIGGING INTO EASTERN MT SOON AFTER DAYBREAK AND WILL BE THE
RESPONSIBLE PARTY FOR ENDING THIS MOIST AIR MASS...AT LEAST
TEMPORARILY BY LATER WED. AT THE SURFACE A FAIRLY DIFFUSE
GRADIENT EXISTS EARLY TODAY WITH A WEAK STATIONARY BOUNDARY NEAR
THE STATE LINE. THE WEAK FLOW HAS ALLOWED FOR LOW CLOUDS AND FOG
TO BE EXPANDING THEIR WAY SOUTHWARD DOWN LAKE MI AIDED BY AMBIENT
DEW POINTS EXCEEDING THE WATER TEMPS BY SEVERAL DEGREES. THE
PRIMARY SURFACE FRONT IS TAKING SHAPE ACROSS THE HIGH PLAINS AND
WILL DEVELOP INTO A COOL FRONT LATER TODAY AS SURFACE CYCLOGENESIS
OCCURS THROUGH NORTHERN MN INTO WESTERN ONTARIO BY THIS EVE. THIS
FRONT WILL MOVE INTO THE FORECAST AREA LATE TONIGHT INTO EARLY WED
MORNING. MULTIPLE ROUNDS OF CONVECTION ARE LIKELY AHEAD OF THIS.
MODEL PREFERENCE...THE RAP AND HRRR GUIDANCE HAVE A GOOD
REPRESENTATION OF ONGOING CONVECTION. THESE HAVE THE SUPPORT OF
SEVERAL OTHER CONVECTIVE ALLOWING MODELS AND HAVE BEEN GUIDED ON
THROUGH MID-AFTERNOON. AFTERWORDS HAVE LEANED TOWARD THE SLIGHTLY
SLOWER 09.00 NAM THAN GFS.
THIS MORNING...REMNANT MCV/SHORT WAVE ENTERING WESTERN IL EARLY
THIS MORNING HAS BEGUN TO INCREASE RADAR ECHOES ACROSS CENTRAL IL
AND THIS TREND IS LIKELY TO CONTINUE WITH SCATTERED CONVECTION
FAVORED DUE TO MODERATE TO HIGH ELEVATED INSTABILITY. NOT A
PARTICULARLY STRONG LOW-LEVEL JET OR ONE WITH HUGE MOISTURE
TRANSPORT THIS MORNING...DUE TO STILL BEING A GOOD DISTANCE AHEAD
OF MID-LEVEL HEIGHT FALLS. SO MORNING SCATTERED TO NUMEROUS
SHOWERS/STORMS ACROSS CENTRAL IL MAY STRUGGLE TO PROGRESS
NORTH/NORTHEAST AT LEAST AT ANY GOOD CLIP OF SPEED. THUS ROCKFORD
TO CHICAGO HAVE POPS ONLY AT THE CHANCE LEVEL...AND MORE SO BASED
ON ISOLATED CELLS DEVELOPING IN THE BROAD WAA AND HIGH PWAT
REGIME. WITH SUCH HIGH PWATS AS YESTERDAY MORNING SHOWED...LOCALLY
HEAVY RAINFALL WOULD BE THE PRIMARILY ASPECT TO KEEP AN EYE ON
WITH THESE MORNING AND EARLY AFTERNOON STORMS. AS FOR EARLY
MORNING FOG/STRATUS THAT HAS BEEN DEVELOPING IN PLACES...ONSHORE
FLOW MAY FAVOR PATCHES OF THIS TO CONTINUE THROUGH MID OR EVEN
LATE MORNING ACROSS NORTHEAST IL AND FAR NORTHWEST IN...STUNTING A
TEMPERATURE CLIMB INITIALLY. OTHERWISE THIS LOOKS LIKE IT SHOULD
BEGIN DISSIPATING/RETREATING NORTH AFTER THAT TIME.
CONFIDENCE...HIGH.
THIS AFTERNOON THROUGH TONIGHT...THE END OF THE RAP RUN AGREES
CLOSELY WITH THE NAM IN TAKING THE SHORT WAVES AND ASSOCIATED 500
AND 700MB SPEED MAXS ACROSS THE DAKOTAS AND NORTHERN NEBRASKA
EARLY THIS MORNING AND TRACKING THAT EAST INTO SOUTHERN WI AND
NORTHERN IL BY MID TO LATE AFTERNOON. ON THE SYNOPTIC SCALE AT
THAT TIME...THE LOW-LEVEL JET AND MOISTURE TRANSPORT WILL ALSO BE
ON THE EXPANSE FROM MO INTO EASTERN IA/WESTERN IL. MIXED LAYER
INSTABILITY WILL BE HIGH OVER THIS AREA INCLUDING THE WESTERN
FORECAST AREA GIVEN TEMPS IN THE UPPER 80S TO LOWER 90S. WHILE
SOME FORM OF MCS OR MULTIPLE CLUSTERS ARE PROBABLE TO BE MOVING
EASTWARD OVER SOUTHERN WI/FAR NORTHERN IL DURING THE AFTERNOON
WITH THE SHORT WAVES...DEVELOPMENT IS FAVORED TO WORK ITS WAY
SOUTH AND BACK TO THE SOUTHWEST FROM THERE IN THE MOIST UNSTABLE
AIR MASS DURING THE MID-AFTERNOON. DEEP LAYER SHEAR IS ANTICIPATED
TO BE INCREASING TO AROUND 30-35 KT BY LATE AFTERNOON WITH
ORGANIZED STORMS EXPECTED TO BE ALL WORKING THEIR WAY EASTWARD. AS
THE PRIMARY UPPER TROUGH APPROACHES THIS EVENING...LARGER SCALE
ASCENT AND FORCING IS LIKELY TO CONTINUE REGIONAL DEVELOPMENT OF
STORMS NEAR AND AHEAD OF THE SURFACE FRONT. SO WHILE THERE LOOKS
TO BE TWO PRIMARY FOCUSES FOR STORMS THIS AFTERNOON INTO
TONIGHT...THERE IS NOT REALLY ANTICIPATED TO BE MUCH OF A BREAK
AND THE HIGH PWAT AND UNSTABLE AIR SHOULD ALLOW FOR PLENTY OF
COVERAGE. THAT COVERAGE MAY INITIALLY BE A LITTLE LIMITED
DEPENDING ON DEBRIS CLOUD COVER BUT IS ANTICIPATED TO BE ITS
HIGHEST LATER THIS AFTERNOON THROUGH EARLY OVERNIGHT.
THE MOST FAVORED MODE FOR STORMS IS MULTICELL AND SEGMENTS
CAPABLE OF SCATTERED DAMAGING WINDS...ESPECIALLY AS THE STRONGER
MID-LEVEL JET OVERRIDES THE FRONT THIS EVENING INTO EARLY
OVERNIGHT. SOME DEVELOPMENT THIS AFTERNOON THROUGH MID-EVE HAS
THE POTENTIAL TO BE SUPERCELLULAR. THE LOW-LEVEL SHEAR IS FAIRLY
ANEMIC MUCH OF THIS AFTERNOON /AOB 10 KT/ BUT QUICKLY INCREASES
LATE INTO EARLY THIS EVE DUE TO THE DEEPENING LOW AND INCREASING
LLJ. THIS WILL HELP FAVOR COLD POOL SUSTAINABILITY AND DOES PRESENT
AT LEAST SOME TORNADO THREAT...ALTHOUGH IT LOOKS LIKE SURFACE
WINDS MAY BE BACKED MORE TO THE WEST OF THE FORECAST AREA
IMMEDIATELY AHEAD OF A SUBTLE SECONDARY SURFACE LOW MOVING UP THE
FRONT. SO THE PRIMARY THREAT WILL REMAIN WIND AND OF COURSE HEAVY
RAIN WITH EXTREMELY EFFICIENT RAIN PRODUCTION WILL OCCUR IN ANY
STORMS TODAY AND TONIGHT. EVEN THOUGH FORWARD PROPAGATION OF
STORMS SHOULD BE ON THE INCREASE TONIGHT...SO WILL DEEP MOISTURE
REPLENISHMENT AND SIMPLY PUT THE ABSOLUTE MOISTURE IS SO HIGH IT
WONT TAKE MUCH TO GET HIGH RAINFALL RATES SUCH AS WE SAW YESTERDAY
MORNING. THERE WILL LIKELY BE SWATHS OF RAINFALL IN EXCESS OF ONE
TO TWO INCHES ACROSS THE IMMEDIATE REGION...BUT WHERE EXACTLY
THEY OCCUR IS TOO CHALLENGING TO LOCK DOWN. DEBATED ON A FLASH
FLOOD WATCH BUT FEEL THE THREAT IS TOO LOCALIZED AT THIS TIME FOR
A WATCH.
CONFIDENCE...MEDIUM.
WEDNESDAY...ONGOING SCATTERED SHOWERS AND STORMS ARE POSSIBLE
ACROSS MAINLY THE SOUTHERN AND EASTERN FORECAST AREA IN THE
MORNING WITH STILL AT LEAST SOME HEAVY RAIN THREAT. WARM
850-925MB AIR BEHIND THE SURFACE WIND SHIFT WILL STILL FAVORED
HIGHS IN THE MID TO POSSIBLY EVEN UPPER 80S IN THE SOUTH. DRIER
AIR WILL GRADUALLY FILTER IN DURING THE LATER AFTERNOON AND NIGHT
PER GUIDANCE.
CONFIDENCE...HIGH.
THURSDAY THROUGH MONDAY...PRIMARILY DRY WEATHER IS EXPECTED OVER
THE AREA ALTHOUGH THE TREND IN BOTH THE EC AND GFS THEIR LAST
MULTIPLE RUNS SUPPORTS WARMER TEMPERATURES THIS WEEKEND WITH MID
AND MAYBE EVEN UPPER 80S SEEN. HAVE COLLABORATED AND LEANED TOWARD
THE WARMER MEX GUIDANCE. THE PATTERN STILL APPEARS BLOCKED JUST
WITH THE AREA MORE UNDER THE INFLUENCE OF THE UPPER RIDGE TO THE
WEST.
MTF
&&
.HYDROLOGY...
410 AM CDT
THE VERY MOIST AIR MASS WILL SUPPORT EFFICIENT RAINFALL PRODUCTION
FROM ANY THUNDERSTORMS TODAY AND TONIGHT. THIS MAY PRESENT FLASH
FLOODING ESPECIALLY ON THE LOCAL LEVEL AS OPPOSED TO ANY WIDESPREAD
THREAT. THAT AND THE FACT THERE IS NOT A GREAT SET UP FOR TRUE
TRAINING STORMS IS WHY NO FLASH FLOOD WATCH AT THIS TIME.
HOWEVER...IF ANY STORMS ARE IN A PARTICULARLY VULNERABLE
AREA...SUCH AS A METRO OR A QUICK-RESPONDING WATERSHED...IT COULD
BE TROUBLE. THESE TYPE OF HIGH RATES WERE ALREADY SEEN YESTERDAY
MORNING WITH A NARROW SWATH OF ONE AND A HALF TO ESTIMATED THREE
PLUS INCHES OF RAIN SEEN FROM RE-FIRING STORMS IN THE WEST CHICAGO
METRO. HIGH RESOLUTION MODEL GUIDANCE INDICATES SUCH SWATHS ARE
PROBABLE IN THE REGION THIS AFTERNOON INTO TONIGHT ALTHOUGH WHERE
IS STILL UNCERTAIN. THE GENERAL RAINFALL FORECAST IS FOR MOST
AREAS TO SEE AROUND AN INCH OR A LITTLE OVER BY WEDNESDAY MORNING.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* FOG WITH REDUCED VIS OF 4SM-6SM DEVELOPING EARLY THIS MORNING.
* SHOWERS WITH POSSIBLE TS REDEVELOPING LATER THIS MORNING AND
CONTINUING THROUGH LATE MORNING.
* REDEVELOPMENT OF SHOWERS/TS ONCE AGAIN LATER THIS AFTERNOON.
* MORE WIDESPREAD SHOWERS/TS EXPECTED TO MOVE ACROSS THE TERMINALS
LATER THIS EVENING AND OVERNIGHT.
* COMPLEX WIND FORECAST WITH VARIABLE/LIGHT WINDS BECOMING
NORTHEAST LATER THIS MORNING...THEN SHIFTING MORE SOUTHERLY
LATER THIS AFTERNOON AND EVENING.
RODRIGUEZ
//DISCUSSION...UPDATED 06Z...
A VERY COMPLEX FORECAST PERIOD FOR THE TERMINALS OVER THE NEXT 24
HOURS AS VARYING WEATHER CONDITIONS AT MULTIPLE TIMES COULD HAVE
IMPACTS ON THE TERMINALS. IN THE NEAR TERM...THE SHOWERS/TS WHICH
HAD DEVELOPED ACROSS NORTHEAST ILLINOIS AND OVER SOUTHERN LAKE
MICHIGAN HAVE SINCE DIMINISHED EARLY THIS MORNING...AND THINK ANY
FURTHER DEVELOPMENT SHOULD REMAIN VERY ISOLATED AND BRIEF OUTSIDE
OF THE TERMINALS. WITH EXPECTED CLEARING...LIGHT WINDS AND A VERY
MOIST ENVIRONMENT SHOULD SUPPORT FOG DEVELOPMENT OVER THE
TERMINALS THIS MORNING WITH VIS RESTRICTION EXPECTED. OUTSIDE OF
THIS DEVELOPMENT...A LIGHT NORTHERLY WIND OVER THE LAKE WITH LOW
CEILINGS AND VIS FURTHER NORTH TOWARDS THE MIDDLE PART OF THE LAKE
RAISES SOME CONCERNS FOR POTENTIAL LOWER CEILINGS AND FOG TO MOVE
ACROSS THE TERMINALS NEAR THE LAKE...ORD/MDW/GYY. EVEN IF THE
CLOUDS/FOG TO THE NORTH DONT QUITE MAKE IT THIS FAR SOUTH...COOLER
AIR MOVING INTO A VERY MOIST ENVIRONMENT COULD SUPPORT LOW
CLOUD/FOG DEVELOPMENT NEAR THE LAKE SHORE ANYWAYS. CONFIDENCE IS
LOW WITH REGARDS TO THE POTENTIAL BUT WILL NEED TO MONITOR THIS
AND ADJUST AS NEEDED.
EXPECT REDEVELOPMENT OF SHOWERS/TS LATER THIS MORNING AS ANOTHER
MID LEVEL DISTURBANCE APPROACHES FROM THE WEST...WITH THIS
SCATTERED DEVELOPMENT POSSIBLY CONTINUING THROUGH MID DAY.
ALTHOUGH SHOULD SEE A DIMINISHING TREND INTO THE EARLY
AFTERNOON...REDEVELOPMENT IN AND AROUND THE TERMINALS WILL ONCE
AGAIN BE POSSIBLE LATE THIS AFTERNOON THROUGH THE EARLY EVENING.
MORE WIDESPREAD SHOWERS/THUNDERSTORMS ARE EXPECTED TO MOVE ACROSS
THE TERMINALS LATE THIS EVENING AND OVERNIGHT BEFORE EXITING EARLY
WEDNESDAY MORNING.
THE WIND FORECAST IS RATHER COMPLEX AS A WEAK GRADIENT WITH
SEVERAL BOUNDARIES MOVING ACROSS THE AREA ARE IN PLACE. WITH THESE
FEATURES IN PLACE...WIND DIRECTION AND SPEED WILL LIKELY RANGE
SUBSTANTIALLY FROM TERMINAL TO THE OTHER. LIGHT AND VARIABLE WINDS
FOR ALL OF THE TERMINALS EARLY THIS MORNING WILL PICK UP LATER
THIS MORNING WITH RFD THE ONLY SITE OBSERVING A MORE SOUTHERLY
DIRECTION EARLY ON. THE OTHER SITES SHOULD HOLD ONTO A NORTHEAST
DIRECTION LATER THIS MORNING...LIGHT AT FIRST BUT PICKING UP IN
SPEEDS. THEN AS THE GRADIENT TIGHTENS OUT AHEAD OF AN APPROACHING
SYSTEM...DO EXPECT A TRANSITION TO MORE OF A SOUTHERLY DIRECTION
TO OCCUR LATER THIS AFTERNOON AND THEN CONTINUE INTO THE EVENING
HOURS.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM CONFIDENCE WITH FOG/REDUCED VIS.
* LOW MEDIUM CONFIDENCE WITH SHOWERS/TS LATER THIS MORNING.
* MEDIUM CONFIDENCE WITH SHOWERS/TS THIS AFTERNOON.
* MEDIUM CONFIDENCE WITH SHOWERS/TS LATER THIS EVENING/OVERNIGHT.
* LOW/MEDIUM CONFIDENCE ON WIND SPEED/DIRECTION.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
* WEDNESDAY...CHANCE OF TSRA...MAINLY IN THE MORNING.
* THURSDAY THROUGH SUNDAY...DRY/VFR.
&&
.MARINE...
312 PM CDT
A WEAK LOW IS OVER SOUTHERN WISCONSIN AND IT WILL MOVE OVER THE LAKE
TONIGHT REACHING THE EASTERN GREAT LAKES BY MORNING BEFORE
DISSIPATING. WINDS WILL TURN NORTHEAST AND DIMINISH TO 10 KT OR
LESS BEHIND THE LOW. A LOW FORMS OVER THE CENTRAL PLAINS TONIGHT
AND WINDS VEER TO S TO SE AHEAD OF IT TOMORROW. S TO SW WINDS
INCREASE TO 20 KT TUESDAY NIGHT AND THEN BECOME W TO NW BEHIND THE
LOW WEDNESDAY MORNING. A HIGH FORMS OVER THE PLAINS WEDNESDAY AND
THEN MOVES OVER THE LAKE THURSDAY. WINDS BECOME LIGHT UNDER THE
HIGH AND THEN TURN S TO SE ON THE BACKSIDE OF THE HIGH FRIDAY
NIGHT. WHILE THE CENTER OF THE HIGH SHIFTS OVER NEW ENGLAND
SATURDAY...THE LAKE WILL STILL HAVE S TO SE FLOW THROUGH THE END OF
THE WEEKEND.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ868-LMZ870-LMZ872-LMZ874
UNTIL 3 PM TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
348 AM CDT TUE JUL 9 2013
.DISCUSSION...
340 AM CDT
SEVERE WEATHER AND HEAVY RAIN POTENTIAL THROUGH TONIGHT WAS WHAT
MUCH OF THE ANALYSIS TIME WAS SPENT ON THIS MORNING. WHAT MAINLY
WAS TRYING TO DO WAS LOCK DOWN A TIMING FOR AN IMPROVED SEVERE
WEATHER THREAT /MID-AFTERNOON THROUGH EARLY OVERNIGHT THOUGH AIR
MASS CAN ALLOW FOR ISOLATED SEVERE ANYTIME/...AND WHAT MAIN
THREATS WOULD BE /WIND AND HEAVY RAIN/. OVERALL NO MAJOR CHANGES
MADE TO THE FORECAST...JUST INCREASING POPS IN THOSE MOST FAVORED
TIMES...RE-ORIENTING POPS SOME...AND REFINING RAINFALL AMOUNT
FORECASTS.
SYNOPSIS...A VERY SOUPY AIR MASS IS ENTRENCHED IN THE REGION
THIS MORNING WITH MID 70S DEW POINTS ACROSS THE FORECAST AREA AND
PWATS ON LAST EVES REGIONAL RAOBS AND EARLY MORNING OBJECTIVE
ANALYSIS BEING AROUND 2 INCHES. NUMEROUS SHORT WAVE IMPULSES...MANY
WITH ASSOCIATED CLUSTERS OF CONVECTION...ARE FOUND UPSTREAM ACROSS
THE HIGH PLAINS AND OVER THE WESTERN CORN BELT ON GOES WATER VAPOR
IMAGERY. THE PRIMARY UPPER LEVEL SHORT WAVE TROUGH WILL BE
DIGGING INTO EASTERN MT SOON AFTER DAYBREAK AND WILL BE THE
RESPONSIBLE PARTY FOR ENDING THIS MOIST AIR MASS...AT LEAST
TEMPORARILY BY LATER WED. AT THE SURFACE A FAIRLY DIFFUSE
GRADIENT EXISTS EARLY TODAY WITH A WEAK STATIONARY BOUNDARY NEAR
THE STATE LINE. THE WEAK FLOW HAS ALLOWED FOR LOW CLOUDS AND FOG
TO BE EXPANDING THEIR WAY SOUTHWARD DOWN LAKE MI AIDED BY AMBIENT
DEW POINTS EXCEEDING THE WATER TEMPS BY SEVERAL DEGREES. THE
PRIMARY SURFACE FRONT IS TAKING SHAPE ACROSS THE HIGH PLAINS AND
WILL DEVELOP INTO A COOL FRONT LATER TODAY AS SURFACE CYCLOGENESIS
OCCURS THROUGH NORTHERN MN INTO WESTERN ONTARIO BY THIS EVE. THIS
FRONT WILL MOVE INTO THE FORECAST AREA LATE TONIGHT INTO EARLY WED
MORNING. MULTIPLE ROUNDS OF CONVECTION ARE LIKELY AHEAD OF THIS.
MODEL PREFERENCE...THE RAP AND HRRR GUIDANCE HAVE A GOOD
REPRESENTATION OF ONGOING CONVECTION. THESE HAVE THE SUPPORT OF
SEVERAL OTHER CONVECTIVE ALLOWING MODELS AND HAVE BEEN GUIDED ON
THROUGH MID-AFTERNOON. AFTERWORDS HAVE LEANED TOWARD THE SLIGHTLY
SLOWER 09.00 NAM THAN GFS.
THIS MORNING...REMNANT MCV/SHORT WAVE ENTERING WESTERN IL EARLY
THIS MORNING HAS BEGUN TO INCREASE RADAR ECHOES ACROSS CENTRAL IL
AND THIS TREND IS LIKELY TO CONTINUE WITH SCATTERED CONVECTION
FAVORED DUE TO MODERATE TO HIGH ELEVATED INSTABILITY. NOT A
PARTICULARLY STRONG LOW-LEVEL JET OR ONE WITH HUGE MOISTURE
TRANSPORT THIS MORNING...DUE TO STILL BEING A GOOD DISTANCE AHEAD
OF MID-LEVEL HEIGHT FALLS. SO MORNING SCATTERED TO NUMEROUS
SHOWERS/STORMS ACROSS CENTRAL IL MAY STRUGGLE TO PROGRESS
NORTH/NORTHEAST AT LEAST AT ANY GOOD CLIP OF SPEED. THUS ROCKFORD
TO CHICAGO HAVE POPS ONLY AT THE CHANCE LEVEL...AND MORE SO BASED
ON ISOLATED CELLS DEVELOPING IN THE BROAD WAA AND HIGH PWAT
REGIME. WITH SUCH HIGH PWATS AS YESTERDAY MORNING SHOWED...LOCALLY
HEAVY RAINFALL WOULD BE THE PRIMARILY ASPECT TO KEEP AN EYE ON
WITH THESE MORNING AND EARLY AFTERNOON STORMS. AS FOR EARLY
MORNING FOG/STRATUS THAT HAS BEEN DEVELOPING IN PLACES...ONSHORE
FLOW MAY FAVOR PATCHES OF THIS TO CONTINUE THROUGH MID OR EVEN
LATE MORNING ACROSS NORTHEAST IL AND FAR NORTHWEST IN...STUNTING A
TEMPERATURE CLIMB INITIALLY. OTHERWISE THIS LOOKS LIKE IT SHOULD
BEGIN DISSIPATING/RETREATING NORTH AFTER THAT TIME.
CONFIDENCE...HIGH.
THIS AFTERNOON THROUGH TONIGHT...THE END OF THE RAP RUN AGREES
CLOSELY WITH THE NAM IN TAKING THE SHORT WAVES AND ASSOCIATED 500
AND 700MB SPEED MAXS ACROSS THE DAKOTAS AND NORTHERN NEBRASKA
EARLY THIS MORNING AND TRACKING THAT EAST INTO SOUTHERN WI AND
NORTHERN IL BY MID TO LATE AFTERNOON. ON THE SYNOPTIC SCALE AT
THAT TIME...THE LOW-LEVEL JET AND MOISTURE TRANSPORT WILL ALSO BE
ON THE EXPANSE FROM MO INTO EASTERN IA/WESTERN IL. MIXED LAYER
INSTABILITY WILL BE HIGH OVER THIS AREA INCLUDING THE WESTERN
FORECAST AREA GIVEN TEMPS IN THE UPPER 80S TO LOWER 90S. WHILE
SOME FORM OF MCS OR MULTIPLE CLUSTERS ARE PROBABLE TO BE MOVING
EASTWARD OVER SOUTHERN WI/FAR NORTHERN IL DURING THE AFTERNOON
WITH THE SHORT WAVES...DEVELOPMENT IS FAVORED TO WORK ITS WAY
SOUTH AND BACK TO THE SOUTHWEST FROM THERE IN THE MOIST UNSTABLE
AIR MASS DURING THE MID-AFTERNOON. DEEP LAYER SHEAR IS ANTICIPATED
TO BE INCREASING TO AROUND 30-35 KT BY LATE AFTERNOON WITH
ORGANIZED STORMS EXPECTED TO BE ALL WORKING THEIR WAY EASTWARD. AS
THE PRIMARY UPPER TROUGH APPROACHES THIS EVENING...LARGER SCALE
ASCENT AND FORCING IS LIKELY TO CONTINUE REGIONAL DEVELOPMENT OF
STORMS NEAR AND AHEAD OF THE SURFACE FRONT. SO WHILE THERE LOOKS
TO BE TWO PRIMARY FOCUSES FOR STORMS THIS AFTERNOON INTO
TONIGHT...THERE IS NOT REALLY ANTICIPATED TO BE MUCH OF A BREAK
AND THE HIGH PWAT AND UNSTABLE AIR SHOULD ALLOW FOR PLENTY OF
COVERAGE. THAT COVERAGE MAY INITIALLY BE A LITTLE LIMITED
DEPENDING ON DEBRIS CLOUD COVER BUT IS ANTICIPATED TO BE ITS
HIGHEST LATER THIS AFTERNOON THROUGH EARLY OVERNIGHT.
THE MOST FAVORED MODE FOR STORMS IS MULTICELL AND SEGMENTS
CAPABLE OF SCATTERED DAMAGING WINDS...ESPECIALLY AS THE STRONGER
MID-LEVEL JET OVERRIDES THE FRONT THIS EVENING INTO EARLY
OVERNIGHT. SOME DEVELOPMENT THIS AFTERNOON THROUGH MID-EVE HAS
THE POTENTIAL TO BE SUPERCELLULAR. THE LOW-LEVEL SHEAR IS FAIRLY
ANEMIC MUCH OF THIS AFTERNOON /AOB 10 KT/ BUT QUICKLY INCREASES
LATE INTO EARLY THIS EVE DUE TO THE DEEPENING LOW AND INCREASING
LLJ. THIS WILL HELP FAVOR COLD POOL SUSTAINABILITY AND DOES PRESENT
AT LEAST SOME TORNADO THREAT...ALTHOUGH IT LOOKS LIKE SURFACE
WINDS MAY BE BACKED MORE TO THE WEST OF THE FORECAST AREA
IMMEDIATELY AHEAD OF A SUBTLE SECONDARY SURFACE LOW MOVING UP THE
FRONT. SO THE PRIMARY THREAT WILL REMAIN WIND AND OF COURSE HEAVY
RAIN WITH EXTREMELY EFFICIENT RAIN PRODUCTION WILL OCCUR IN ANY
STORMS TODAY AND TONIGHT. EVEN THOUGH FORWARD PROPAGATION OF
STORMS SHOULD BE ON THE INCREASE TONIGHT...SO WILL DEEP MOISTURE
REPLENISHMENT AND SIMPLY PUT THE ABSOLUTE MOISTURE IS SO HIGH IT
WONT TAKE MUCH TO GET HIGH RAINFALL RATES SUCH AS WE SAW YESTERDAY
MORNING. THERE WILL LIKELY BE SWATHS OF RAINFALL IN EXCESS OF ONE
TO TWO INCHES ACROSS THE IMMEDIATE REGION...BUT WHERE EXACTLY
THEY OCCUR IS TOO CHALLENGING TO LOCK DOWN. DEBATED ON A FLASH
FLOOD WATCH BUT FEEL THE THREAT IS TOO LOCALIZED AT THIS TIME FOR
A WATCH.
CONFIDENCE...MEDIUM.
THE REMAINDER OF THE DISCUSSION WILL BE ISSUED SHORTLY.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* FOG WITH REDUCED VIS OF 4SM-6SM DEVELOPING EARLY THIS MORNING.
* SHOWERS WITH POSSIBLE TS REDEVELOPING LATER THIS MORNING AND
CONTINUING THROUGH LATE MORNING.
* REDEVELOPMENT OF SHOWERS/TS ONCE AGAIN LATER THIS AFTERNOON.
* MORE WIDESPREAD SHOWERS/TS EXPECTED TO MOVE ACROSS THE TERMINALS
LATER THIS EVENING AND OVERNIGHT.
* COMPLEX WIND FORECAST WITH VARIABLE/LIGHT WINDS BECOMING
NORTHEAST LATER THIS MORNING...THEN SHIFTING MORE SOUTHERLY
LATER THIS AFTERNOON AND EVENING.
RODRIGUEZ
//DISCUSSION...UPDATED 06Z...
A VERY COMPLEX FORECAST PERIOD FOR THE TERMINALS OVER THE NEXT 24
HOURS AS VARYING WEATHER CONDITIONS AT MULTIPLE TIMES COULD HAVE
IMPACTS ON THE TERMINALS. IN THE NEAR TERM...THE SHOWERS/TS WHICH
HAD DEVELOPED ACROSS NORTHEAST ILLINOIS AND OVER SOUTHERN LAKE
MICHIGAN HAVE SINCE DIMINISHED EARLY THIS MORNING...AND THINK ANY
FURTHER DEVELOPMENT SHOULD REMAIN VERY ISOLATED AND BRIEF OUTSIDE
OF THE TERMINALS. WITH EXPECTED CLEARING...LIGHT WINDS AND A VERY
MOIST ENVIRONMENT SHOULD SUPPORT FOG DEVELOPMENT OVER THE
TERMINALS THIS MORNING WITH VIS RESTRICTION EXPECTED. OUTSIDE OF
THIS DEVELOPMENT...A LIGHT NORTHERLY WIND OVER THE LAKE WITH LOW
CEILINGS AND VIS FURTHER NORTH TOWARDS THE MIDDLE PART OF THE LAKE
RAISES SOME CONCERNS FOR POTENTIAL LOWER CEILINGS AND FOG TO MOVE
ACROSS THE TERMINALS NEAR THE LAKE...ORD/MDW/GYY. EVEN IF THE
CLOUDS/FOG TO THE NORTH DONT QUITE MAKE IT THIS FAR SOUTH...COOLER
AIR MOVING INTO A VERY MOIST ENVIRONMENT COULD SUPPORT LOW
CLOUD/FOG DEVELOPMENT NEAR THE LAKE SHORE ANYWAYS. CONFIDENCE IS
LOW WITH REGARDS TO THE POTENTIAL BUT WILL NEED TO MONITOR THIS
AND ADJUST AS NEEDED.
EXPECT REDEVELOPMENT OF SHOWERS/TS LATER THIS MORNING AS ANOTHER
MID LEVEL DISTURBANCE APPROACHES FROM THE WEST...WITH THIS
SCATTERED DEVELOPMENT POSSIBLY CONTINUING THROUGH MID DAY.
ALTHOUGH SHOULD SEE A DIMINISHING TREND INTO THE EARLY
AFTERNOON...REDEVELOPMENT IN AND AROUND THE TERMINALS WILL ONCE
AGAIN BE POSSIBLE LATE THIS AFTERNOON THROUGH THE EARLY EVENING.
MORE WIDESPREAD SHOWERS/THUNDERSTORMS ARE EXPECTED TO MOVE ACROSS
THE TERMINALS LATE THIS EVENING AND OVERNIGHT BEFORE EXITING EARLY
WEDNESDAY MORNING.
THE WIND FORECAST IS RATHER COMPLEX AS A WEAK GRADIENT WITH
SEVERAL BOUNDARIES MOVING ACROSS THE AREA ARE IN PLACE. WITH THESE
FEATURES IN PLACE...WIND DIRECTION AND SPEED WILL LIKELY RANGE
SUBSTANTIALLY FROM TERMINAL TO THE OTHER. LIGHT AND VARIABLE WINDS
FOR ALL OF THE TERMINALS EARLY THIS MORNING WILL PICK UP LATER
THIS MORNING WITH RFD THE ONLY SITE OBSERVING A MORE SOUTHERLY
DIRECTION EARLY ON. THE OTHER SITES SHOULD HOLD ONTO A NORTHEAST
DIRECTION LATER THIS MORNING...LIGHT AT FIRST BUT PICKING UP IN
SPEEDS. THEN AS THE GRADIENT TIGHTENS OUT AHEAD OF AN APPROACHING
SYSTEM...DO EXPECT A TRANSITION TO MORE OF A SOUTHERLY DIRECTION
TO OCCUR LATER THIS AFTERNOON AND THEN CONTINUE INTO THE EVENING
HOURS.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM CONFIDENCE WITH FOG/REDUCED VIS.
* LOW MEDIUM CONFIDENCE WITH SHOWERS/TS LATER THIS MORNING.
* MEDIUM CONFIDENCE WITH SHOWERS/TS THIS AFTERNOON.
* MEDIUM CONFIDENCE WITH SHOWERS/TS LATER THIS EVENING/OVERNIGHT.
* LOW/MEDIUM CONFIDENCE ON WIND SPEED/DIRECTION.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
* WEDNESDAY...CHANCE OF TSRA...MAINLY IN THE MORNING.
* THURSDAY THROUGH SUNDAY...DRY/VFR.
&&
.MARINE...
312 PM CDT
A WEAK LOW IS OVER SOUTHERN WISCONSIN AND IT WILL MOVE OVER THE LAKE
TONIGHT REACHING THE EASTERN GREAT LAKES BY MORNING BEFORE
DISSIPATING. WINDS WILL TURN NORTHEAST AND DIMINISH TO 10 KT OR
LESS BEHIND THE LOW. A LOW FORMS OVER THE CENTRAL PLAINS TONIGHT
AND WINDS VEER TO S TO SE AHEAD OF IT TOMORROW. S TO SW WINDS
INCREASE TO 20 KT TUESDAY NIGHT AND THEN BECOME W TO NW BEHIND THE
LOW WEDNESDAY MORNING. A HIGH FORMS OVER THE PLAINS WEDNESDAY AND
THEN MOVES OVER THE LAKE THURSDAY. WINDS BECOME LIGHT UNDER THE
HIGH AND THEN TURN S TO SE ON THE BACKSIDE OF THE HIGH FRIDAY
NIGHT. WHILE THE CENTER OF THE HIGH SHIFTS OVER NEW ENGLAND
SATURDAY...THE LAKE WILL STILL HAVE S TO SE FLOW THROUGH THE END OF
THE WEEKEND.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
148 AM EDT TUE JUL 9 2013
.SYNOPSIS...
ISSUED AT 651 PM EDT MON JUL 8 2013
SHOWER AND THUNDERSTORM COVERAGE WILL INCREASE THROUGH THE EVENING
AND INTO THE OVERNIGHT HOURS TONIGHT WITH LOW TEMPERATURES IN THE
LOW 70S. THERE IS A CHANCE OF SHOWERS AND THUNDERSTORMS AGAIN ON
TUESDAY WITH HIGH TEMPERATURES IN THE UPPER 80S. A FEW OF THE
THUNDERSTORMS COULD BE STRONG TO SEVERE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 314 PM EDT MON JUL 8 2013
COMPLICATED FCST PERIOD WRT CONVECTIVE POTENTIAL THIS EVENING AND
AGAIN ON TUESDAY.
AREA OF SHOWERS AND THUNDERSTORMS THAT DEVELOPED THIS MORNING ACROSS
NE IL HAVE ADVECTED INTO THE NW CWA THIS AFTERNOON. THIS AREA OF
SHOWERS APPEARS TO BE IN A DECAYING STATE...AND HAS WORKED OVER THE
ENVIRONMENT ACROSS MUCH OF THE AREA. THE DEGREE OF RECOVERY LATE
THIS AFTERNOON AND EARLY THIS EVENING WILL BE CRITICAL TO ANY
CONVECTIVE POTENTIAL GOING FORWARD INTO THE OVERNIGHT.
HI RES MODELS HAVE DONE A POOR JOB WITH THE CONVECTIVE EVOLUTION
OVER THE PAST 6 HOURS. HRRR AND 12Z SPC 4KM RUNS HAVE INDICATED A
W-E ORIENTED LINE OF CONVECTION DEVELOPING ACROSS THE LOWER GREAT
LAKES REGION AND SINKING SOUTHWARD ACROSS THE AREA...COINCIDENT WITH
SHORTWAVE ENERGY ADVECTING SOUTHEAST ACROSS THE LOWER GREAT LAKES
PER W/V. THE COVERAGE AND EXTENT OF THIS POTENTIAL CONVECTION WILL
BE HIGHLY DEPENDENT ON ATMOSPHERIC RECOVERY. RECENT RAP13 RUNS DO
INDICATED A STRONG LOW LVL THETA E POOLING ACROSS NRN IL...ADVECTING
INTO NRN IN THROUGH 00Z. THIS OPTIMISTIC SCENARIO WOULD ALLOW
MLCAPES TO RECOVER TO 1000-2000 J/KG. MODEST 0-6 KM BULK SHEAR
VALUES OF 25-30 KTS...AND 850-500 MB LAPSE RATES OF 5.5-6 C/KM WILL
KEEP SEVERE POTENTIAL LOW TO MARGINAL AT THIS POINT....HOWEVER AN
ISOLATED STORM PRODUCING STRONG TO SEVERE WIND GUSTS IS POSSIBLE.
GIVEN ALL OF THESE FACTORS...DECIDED TO LEAVE POPS IN THE SCATTERED
CATEGORY TONIGHT...WITH THE BEST POTENTIAL FOR CONVECTION BETWEEN
22Z AND 04Z.
CONVECTIVE OUTFLOW SHOULD PUSH PRECIP POTENTIAL SOUTHWARD THROUGH
THE OVERNIGHT HOURS...AND HAVE CONFINED SLIGHT CHANCE POPS TO THE
SOUTH. WARM AND MUGGY CONDITIONS ARE EXPECTED AGAIN ON TUESDAY WITH
HIGHS TOPPING OUT IN THE MID TO UPPER 80S...WITH HEAT INDICES IN THE
LOW TO MID 90S. REMNANT CONVECTIVE BOUNDARY MAY BE A FOCUS FOR
SHOWER AND THUNDERSTORM ACTIVITY TOMORROW WITH A JUICED ENVIRONMENT.
UPSTREAM SHORTWAVE EXPECTED TO ADVECT INTO THE REGION LATE TUESDAY
AFTERNOON...WHICH WILL PROVIDE MORE SUPPORT FOR CONVECTION. GIVEN
UNCERTAINTY WITH EVOLUTION OF CONVECTION THIS EVENING...AND
RESULTING BOUNDARY LOCATION...AS WELL AS UNCERTAINTY WITH THE
EVOLUTION OF CONVECTIVELY INDUCED SHORTWAVE...HAVE OPTED TO KEEP
POPS IN THE CHANCE RANGE...WITH THE HIGHEST IN THE AFTERNOON.
POTENTIAL FOR SEVERE WIND GUSTS TOMORROW DOES EXIST GIVEN HIGHLY
UNSTABLE ENVIRONMENT...BUT MODEST BULK SHEAR VALUES OF 25-30 KTS MAY
BE A LIMITING FACTOR FOR STORM ORGANIZATION.
&&
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 314 PM EDT MON JUL 8 2013
SHARPENING MID LVL TROUGH SWEEPING THROUGH SRN CANADA SHRT TERM WILL
PROPEL A VIGOROUS CDFNT THROUGH CWA ON WED. IN LIGHT OF DISPARATE
MODEL GUIDANCE WILL GENERALLY RELY ON HIGHRES CONSENSUS OF FASTER
FROPA ESP WITHIN GUISE OF TUE NIGHT CONVN/MCS AND LIKELY OUTFLW
REMNANT COMPOSITING MORE EFFECTIVE DY3 FORCING MECHANISM SWD TWD
THE OH VALLEY. AS SUCH HAVE SHARPLY CURTAILED POPS ON WED.
AFT THAT...HIGH PRES TO RIDGE SWD ACRS THE LAKES AS MID LVL TROUGH
AMPLIFIES THROUGH NEW ENGLAND BRINGING SEASONABLE TEMPS TO THE
REGION AND DRY WX.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 140 AM EDT TUE JUL 9 2013
POINT/AIRFIELD CHANCES FOR CONVECTION EXIST...THOUGH TOO LOW TO
WARRANT ANY INCLUSION ATTM. BEST FOCUS ASSOCD WITH APPROACH OF NRN
STREAM WAVE LATE IN FORECAST PD AND ADDRESS WITH TEMPO TSRA AT
KSBN...HEAVY RAFL POTENTIAL GIVEN WARM/MOIST TROPOSPHERE DEPTH
SUGGESTS AT LEAST BRIEF IFR VSBYS REDUCTIONS WITHIN/NEAR
CONVECTIVE CELL CORES. TIMING APPEARS JUST OUTSIDE OF CURRENT
FORECAST WINDOW AT KFWA...TO BE INCLUDED WITH 12 UTC ITERATION.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...BENTLEY
SHORT TERM...NG
LONG TERM...T
AVIATION...MURPHY
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AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1244 PM CDT TUE JUL 9 2013
.UPDATE...
ISSUED AT 1050 AM CDT TUE JUL 9 2013
2 MAJOR UPDATES HAVE BEEN SEND THIS MORNING...REFLECTING CHANGES
BASED ON RADAR TRENDS...AND NOW BOTH CONVECTIVE TRENDS COMBINED
WITH MORNING UA ANALYSIS AND EARLY SIGNALS IN MODEL GUIDANCE.
THE PARADE OF TWO MCV FEATURES IS NOTED ON RADAR AND
SATELLITE...AND THUS THE NEXT 4 HOURS WILL CERTAINLY BE OUR MAIN
SHOW WITH RESPECT TO RAINFALL POTENTIAL. AMOUNTS THUS FAR ARE
SCATTERED AND SIGNIFICANT ...OVER 1 INCH......BUT MOST OF THE AREA
RECEIVING ONLY LIGHT AMOUNTS OR NEARLY DRY...ESPECIALLY SOUTH.
SURFACE CAPE WILL BE LIMITED TO ONLY THE SOUTH TODAY AND EARLY
THIS EVENING...THUS OUR BEST POTENTIAL FOR MORE SIGNIFICANT STORMS
IS THERE. ELSEWHERE I HAVE CONTINUED TO LOWER EVENING POPS...AS
WELL AS AFTERNOON POPS IN THE WEST. TONIGHT COULD VERY WELL BE DRY
OVER OUR WESTERN 1/3 OF THE CWA...AND POSSIBLY WESTERN 2/3 IF THE
VEERED MOISTURE PLUME CANNOT RECOVER FROM THE MCV PASSAGES. THIS
GREATLY WILL LOWER THE SEVERE THREAT...AND I WILL AWAIT THE SPC
UPDATE BEFORE UPDATING THE HWO TO REFLECT THAT POSSIBLE LOWERED
MAGNITUDE OF THE THREAT.
TEMPERATURES HAVE BEEN LOWERED TO MAINLY MID 80S HIGHS...WHICH
SHOULD EASILY OCCUR ONCE CONVECTION STOPS FIRING...BUT SAFE TO
SAY...OUR NEAR ADVISORY LEVEL HEAT WILL NOT VERIFY TODAY. IT WILL
MOST CERTAINLY BE QUITE MUGGY OUT THERE.
ERVIN
&&
.SYNOPSIS...
ISSUED AT 330 AM CDT TUE JUL 9 2013
06Z MSAS SFC ANALYSIS SUPPORTIVE OF WEAK LOW OVER CENTRAL SD WITH
STATIONARY FRONT EXTENDING SEWD FROM THE LOW AND BISECTING
EASTERN IA AND NORTHWEST IL. MOISTURE IS POOLING ALONG THE FRONT
WITH DEWPTS OF 70-75F. 00Z KDVN RAOB SHOWS DEEP MOISTURE WITH
PRECIPITABLE WATER VALUES OF NEARLY 2 INCHES... WHICH IS AROUND 160
PERCENT OF NORMAL AND NEARLY 2 STANDARD DEVIATIONS ABOVE THE MEAN.
CONVECTIVELY ENHANCED VORT MAX IS TRACKING THROUGH EASTERN NE ATTM
WITH RADARS SHOWING SHOWERS AND STORMS AHEAD OF THIS FEATURE INTO
WESTERN IA. ADDITIONAL COMPLEX OF STORMS WAS OVER THE DAKOTAS
AHEAD OF COLD FRONT AND SHORTWAVE MOVING EAST THROUGH FAR SOUTHERN
ALBERTA PROVINCE AND NORTHERN MT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CDT TUE JUL 9 2013
SUGGESTIONS OF 2 MAIN ROUNDS OF STORMS THROUGH THE PERIOD. AS
CONVECTIVELY ENHANCED VORT MAX MOVES EAST FROM NE ANTICIPATE
SHOWERS AND STORMS TRACKING AHEAD OF THIS FEATURE TO MOVE ACROSS
THE REGION BY MID AM THROUGH EARLY AFTN. PRIOR TO THE ARRIVAL
OF THESE STORMS COULD SEE ADDITIONAL DEVELOPMENT PRIOR TO MID AM
OVER THE AREA WITH WARM ADVECTION WING. POTENTIAL FOR SOME
STRENGTHENING OF MID LEVEL WINDS AND INTENSIFICATION OF STORMS
BY LATE AM AND AFTN FOR RISK OF FEW STRONG TO ISOLD SEVERE STORMS
WITH MOST RECENT RUNS OF HRRR 2-5KM UPDRAFT HELICITY AND 3 KM
VELOCITY CONTINUING TO SUGGEST THIS RISK NEAR AND ESPECIALLY NORTH
OF I-80. MAY SEE BREAK IN ACTION OR RELATIVE LULL IN ACTIVITY
BY MID-LATE AFTN WITH FOCUS SHIFTING BACK NORTHWEST FOR DEVELOPMENT
AHEAD OF COLD FRONT. LIKELY TO SEE ANOTHER ROUND OF STORMS MOVE
THROUGH THIS EVENING INTO OVERNIGHT AHEAD OF COLD FRONT.
STRENGTHENING 40-60 KT MID LEVEL SPEED MAX SPREADING BEHIND FRONT
COUPLED WITH VERY UNSTABLE ENVIRONMENT WILL SUPPORT RISK OF SEVERE
STORMS WITH POTENTIAL FOR UPSCALE GROWTH TO LINEAR MCS WITH MAINLY
DAMAGING WIND THREAT. HEAVY RAIN WILL BE A CONCERN AS WELL GIVEN
THE DEEP ALMOST TROPICAL MOISTURE IN PLACE. STORMS SHOULD BE MOVING
ALONG MORE THAN WE/VE SEEN OF LATE BUT WILL BE VERY EFFICIENT RAIN
PRODUCERS WITH RATES LIKELY 1-2"/HR. THUS... CANT RULE OUT SOME
LOCALIZED FLASH FLOODING AND WILL HAVE TO BE ESPECIALLY WATCHFULL
OVER PORTIONS OF DELAWARE AND DUBUQUE COUNTIES WHICH HAVE SEEN 2-5
INCHES PAST 24-36 HRS. EXPECT PCPN SHOULD BE DIMINISHING FROM NW
TO SE OVRNGT WITH PASSAGE OF COLD FRONT.
HIGHS TDY TRICKY WITH CLOUDS AND PCPN BUT OVERALL SHOULD RANGE FROM
MID 80S TO THE LOWER 90S. SOME MIXING OUT OF DEWPTS MAY OCCUR BUT
AT LEAST UPPER 60S TO LOWER 70S EXPECTED ON DEWPTS... WHICH COMBINED
WITH TEMPS WILL MAKE FOR HEAT INDICES MAINLY IN THE MID TO UPPER 90S.
COOLER AND DRIER AIR LAGS BEHIND FRONT TNGT... THUS LOWS ONLY DROP
INTO THE UPPER 60S TO LOWER 70S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 330 AM CDT TUE JUL 9 2013
WEDNESDAY AND THURSDAY...AS L/W TROF CONTINUES TO DEEPEN AND
ESTABLISH ACRS THE GRT LKS...SEASONABLY STRONG LLVL HIGH PRESSURE
WILL LOOK TO DUMP DOWN THE NORTHERN PLAINS AND MO RVR VALLEY ON WED.
A FEW POST-FRONTAL SHOWERS AND STORMS MAY BE OCCURRING ACRS THE FAR
EASTERN/SOUTHERN CWA WED MORNING BUT BULK OF THE ACTIVITY SHOULD BE
GONE BY 15Z. VEERING AND INCREASING BOUNDARY LAYER FLOW AS WELL AS
INCOMING SUBSIDENCE SHOULD CLEAR THINGS OUT ON WED...BUT SOME LAG IN
CAA TO ALLOW TEMPS TO WARM INTO THE LOW TO MID 80S EVEN POST-
FRONTALLY. A RATHER BREEZY NORTHWEST TO NORTH WIND OF 15-20 MPH.
CLEAR SKIES AND WIND DROP OFF WED NIGHT TO ALLOW SOME AREA TEMPS TO
DROP OFF INTO THE 50S. LLVL HIGH PRESSURE CONTINUING TO MIGRATE
EASTWARD ACRS THE REGION TO MAKE FOR A CHAMBER OF COMMERCE DAY THU
WITH HIGHS IN THE UPPER 70S TO LOWER 80S...SUNSHINE AND LOWER
HUMIDITY. THU NIGHT SEASONABLY COOL AGAIN WITH LOWS IN THE 50S AND
LOW 60S.
FRIDAY THROUGH NEXT MONDAY...TRENDS OF THE LATEST RUN 00Z MEDIUM
RANGE SOLUTIONS AND ENSEMBLES SUGGEST SOME DIGGING TROFFINESS IN THE
PACIFIC NORTHWEST/WESTERN CANADA TO TRANSLATE INTO PUMPED UP UPPER
RIDGING ACRS THE MID CONUS FRI INTO SAT. THUS WHILE THERMAL DOME
INTENSIFIES ACRS THE GRT BSN INTO THE SOUTHWESTERN PLAINS...MCS
TRACK/RING OF FIRE PATTERN TO ESTABLISH IN NORMAL DEEP SUMMER
LOCATION OF NORTHWESTERN HIGH PLAINS...UPPER MS RVR VALLEY...SOUTHERN
CANADA AND INTO THE GRT LKS. LATEST INDICATIONS SUGGEST A LESSENING
CHANCE FOR SOME OF THIS MCS ACTIVITY TO SPILL DOWN ACRS THE
NORTHERN CWA EITHER FRI NIGHT OR SAT NIGHT WHILE TEMPERATURES START
TO REBOUND BACK TO NORMAL OR EVEN WARMER. BY SUNDAY...WESTERLIES
FIRMLY ESTABLISH ACRS THE U.S.-CANADIAN BORDER REGION WITH UPPER
RIDGING DOMINATING ACRS THE SOUTHERN 2/3S OF THE CONUS. LONGER
RANGE THERMAL PROFILES SUGGEST ENOUGH AIRMASS MODIFICATION TO DRIVE
SUNDAY HIGHS UP INTO AT LEAST THE LOWER 90S ALONG WITH INCREASING
SFC DPTS/HUMIDITY. PASSING WAVE IN THIS PROGRESSIVE FLOW MAY TRY TO
SHUNT DOWN A WEAKENING SFC BOUNDARY DOWN TOWARD OR ACRS THE CWA
LATER SUNDAY NIGHT OR MONDAY AND GET SLOWED AS IT ALIGNS PARALLEL TO
MEAN STEERING FLOW. THUS THIS WINDOW MAY BE THE NEXT REAL CHANCE FOR
SOME PRECIP IN THE AREA AFTER TODAY/TONIGHT. LONGER RANGE SIGNALS ON
THE LATEST RUNS ESPECIALLY THE NEW 00Z ECMWF SUGGESTS THAT THIS
BROAD UPPER RIDGING PATTERN TO CONTINUE TO REIGN ACRS MUCH OF THE
CONUS WELL INTO MID NEXT WEEK...WHILE THE TROPICS CONTINUE TO GET
INTERESTING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1239 PM CDT TUE JUL 9 2013
AS SCATTERED SHOWERS AND STORMS MOVED OVER EASTERN IOWA AND
ILLINOIS EARLIER TODAY...THEY REMOVED MUCH OF THE INSTABILITY
NEEDED FOR THE EALIER FORECAST STRONG THUNDERSTORMS. THUS...ANY
NEW AFTERNOON THUNDERSTORMS AND EVENING STORMS WILL BE MORE
SCATTERED THAN WIDESPREAD...AND DUE TO THIS LOW COVERAGE AND LOW
CONFIDENCE...ALL STORMS HAVE BEEN REMOVED FROM TAFS. VFR
CONDITIONS WITH MID AND HIGH CLOUDS OR CLEAR SKIES...AND SOUTH
WINDS WILL CONTINUE THROUGH LATE EVENING...WHEN THE COLD FRONT
ARRIVES. AS THE FRONT ARRIVES...WINDS MAY DECREASE ALLOWING FOR
PATCHY FOG DEVELOPMENT...AND A TEMPO FOR FOG HAS BEEN PLACED INTO
ALL TAFS FROM AROUND 04Z TO 08Z TONIGHT. AFTER THIS...NORTHWEST
WINDS SHOULD DISSIPATE FOG...AND RETURN TO VFR CONDITIONS.
ERVIN
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...ERVIN
SYNOPSIS...05
SHORT TERM...05
LONG TERM...12
AVIATION...ERVIN
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1057 AM CDT TUE JUL 9 2013
.UPDATE...
ISSUED AT 1050 AM CDT TUE JUL 9 2013
2 MAJOR UPDATES HAVE BEEN SEND THIS MORNING...REFLECTING CHANGES
BASED ON RADAR TRENDS...AND NOW BOTH CONVECTIVE TRENDS COMBINED
WITH MORNING UA ANALYSIS AND EARLY SIGNALS IN MODEL GUIDANCE.
THE PARADE OF TWO MCV FEATURES IS NOTED ON RADAR AND
SATELLITE...AND THUS THE NEXT 4 HOURS WILL CERTAINLY BE OUR MAIN
SHOW WITH RESPECT TO RAINFALL POTENTIAL. AMOUNTS THUS FAR ARE
SCATTERED AND SIGNIFICANT ...OVER 1 INCH......BUT MOST OF THE AREA
RECEIVING ONLY LIGHT AMOUNTS OR NEARLY DRY...ESPECIALLY SOUTH.
SURFACE CAPE WILL BE LIMITED TO ONLY THE SOUTH TODAY AND EARLY
THIS EVENING...THUS OUR BEST POTENTIAL FOR MORE SIGNIFICANT STORMS
IS THERE. ELSEWHERE I HAVE CONTINUED TO LOWER EVENING POPS...AS
WELL AS AFTERNOON POPS IN THE WEST. TONIGHT COULD VERY WELL BE DRY
OVER OUR WESTERN 1/3 OF THE CWA...AND POSSIBLY WESTERN 2/3 IF THE
VEERED MOISTURE PLUME CANNOT RECOVER FROM THE MCV PASSAGES. THIS
GREATLY WILL LOWER THE SEVERE THREAT...AND I WILL AWAIT THE SPC
UPDATE BEFORE UPDATING THE HWO TO REFLECT THAT POSSIBLE LOWERED
MAGNITUDE OF THE THREAT.
TEMPERATURES HAVE BEEN LOWERED TO MAINLY MID 80S HIGHS...WHICH
SHOULD EASILY OCCUR ONCE CONVECTION STOPS FIRING...BUT SAFE TO
SAY...OUR NEAR ADVISORY LEVEL HEAT WILL NOT VERIFY TODAY. IT WILL
MOST CERTAINLY BE QUITE MUGGY OUT THERE.
ERVIN
&&
.SYNOPSIS...
ISSUED AT 330 AM CDT TUE JUL 9 2013
06Z MSAS SFC ANALYSIS SUPPORTIVE OF WEAK LOW OVER CENTRAL SD WITH
STATIONARY FRONT EXTENDING SEWD FROM THE LOW AND BISECTING
EASTERN IA AND NORTHWEST IL. MOISTURE IS POOLING ALONG THE FRONT
WITH DEWPTS OF 70-75F. 00Z KDVN RAOB SHOWS DEEP MOISTURE WITH
PRECIPITABLE WATER VALUES OF NEARLY 2 INCHES... WHICH IS AROUND 160
PERCENT OF NORMAL AND NEARLY 2 STANDARD DEVIATIONS ABOVE THE MEAN.
CONVECTIVELY ENHANCED VORT MAX IS TRACKING THROUGH EASTERN NE ATTM
WITH RADARS SHOWING SHOWERS AND STORMS AHEAD OF THIS FEATURE INTO
WESTERN IA. ADDITIONAL COMPLEX OF STORMS WAS OVER THE DAKOTAS
AHEAD OF COLD FRONT AND SHORTWAVE MOVING EAST THROUGH FAR SOUTHERN
ALBERTA PROVINCE AND NORTHERN MT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CDT TUE JUL 9 2013
SUGGESTIONS OF 2 MAIN ROUNDS OF STORMS THROUGH THE PERIOD. AS
CONVECTIVELY ENHANCED VORT MAX MOVES EAST FROM NE ANTICIPATE
SHOWERS AND STORMS TRACKING AHEAD OF THIS FEATURE TO MOVE ACROSS
THE REGION BY MID AM THROUGH EARLY AFTN. PRIOR TO THE ARRIVAL
OF THESE STORMS COULD SEE ADDITIONAL DEVELOPMENT PRIOR TO MID AM
OVER THE AREA WITH WARM ADVECTION WING. POTENTIAL FOR SOME
STRENGTHENING OF MID LEVEL WINDS AND INTENSIFICATION OF STORMS
BY LATE AM AND AFTN FOR RISK OF FEW STRONG TO ISOLD SEVERE STORMS
WITH MOST RECENT RUNS OF HRRR 2-5KM UPDRAFT HELICITY AND 3 KM
VELOCITY CONTINUING TO SUGGEST THIS RISK NEAR AND ESPECIALLY NORTH
OF I-80. MAY SEE BREAK IN ACTION OR RELATIVE LULL IN ACTIVITY
BY MID-LATE AFTN WITH FOCUS SHIFTING BACK NORTHWEST FOR DEVELOPMENT
AHEAD OF COLD FRONT. LIKELY TO SEE ANOTHER ROUND OF STORMS MOVE
THROUGH THIS EVENING INTO OVERNIGHT AHEAD OF COLD FRONT.
STRENGTHENING 40-60 KT MID LEVEL SPEED MAX SPREADING BEHIND FRONT
COUPLED WITH VERY UNSTABLE ENVIRONMENT WILL SUPPORT RISK OF SEVERE
STORMS WITH POTENTIAL FOR UPSCALE GROWTH TO LINEAR MCS WITH MAINLY
DAMAGING WIND THREAT. HEAVY RAIN WILL BE A CONCERN AS WELL GIVEN
THE DEEP ALMOST TROPICAL MOISTURE IN PLACE. STORMS SHOULD BE MOVING
ALONG MORE THAN WE/VE SEEN OF LATE BUT WILL BE VERY EFFICIENT RAIN
PRODUCERS WITH RATES LIKELY 1-2"/HR. THUS... CANT RULE OUT SOME
LOCALIZED FLASH FLOODING AND WILL HAVE TO BE ESPECIALLY WATCHFULL
OVER PORTIONS OF DELAWARE AND DUBUQUE COUNTIES WHICH HAVE SEEN 2-5
INCHES PAST 24-36 HRS. EXPECT PCPN SHOULD BE DIMINISHING FROM NW
TO SE OVRNGT WITH PASSAGE OF COLD FRONT.
HIGHS TDY TRICKY WITH CLOUDS AND PCPN BUT OVERALL SHOULD RANGE FROM
MID 80S TO THE LOWER 90S. SOME MIXING OUT OF DEWPTS MAY OCCUR BUT
AT LEAST UPPER 60S TO LOWER 70S EXPECTED ON DEWPTS... WHICH COMBINED
WITH TEMPS WILL MAKE FOR HEAT INDICES MAINLY IN THE MID TO UPPER 90S.
COOLER AND DRIER AIR LAGS BEHIND FRONT TNGT... THUS LOWS ONLY DROP
INTO THE UPPER 60S TO LOWER 70S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 330 AM CDT TUE JUL 9 2013
WEDNESDAY AND THURSDAY...AS L/W TROF CONTINUES TO DEEPEN AND
ESTABLISH ACRS THE GRT LKS...SEASONABLY STRONG LLVL HIGH PRESSURE
WILL LOOK TO DUMP DOWN THE NORTHERN PLAINS AND MO RVR VALLEY ON WED.
A FEW POST-FRONTAL SHOWERS AND STORMS MAY BE OCCURRING ACRS THE FAR
EASTERN/SOUTHERN CWA WED MORNING BUT BULK OF THE ACTIVITY SHOULD BE
GONE BY 15Z. VEERING AND INCREASING BOUNDARY LAYER FLOW AS WELL AS
INCOMING SUBSIDENCE SHOULD CLEAR THINGS OUT ON WED...BUT SOME LAG IN
CAA TO ALLOW TEMPS TO WARM INTO THE LOW TO MID 80S EVEN POST-
FRONTALLY. A RATHER BREEZY NORTHWEST TO NORTH WIND OF 15-20 MPH.
CLEAR SKIES AND WIND DROP OFF WED NIGHT TO ALLOW SOME AREA TEMPS TO
DROP OFF INTO THE 50S. LLVL HIGH PRESSURE CONTINUING TO MIGRATE
EASTWARD ACRS THE REGION TO MAKE FOR A CHAMBER OF COMMERCE DAY THU
WITH HIGHS IN THE UPPER 70S TO LOWER 80S...SUNSHINE AND LOWER
HUMIDITY. THU NIGHT SEASONABLY COOL AGAIN WITH LOWS IN THE 50S AND
LOW 60S.
FRIDAY THROUGH NEXT MONDAY...TRENDS OF THE LATEST RUN 00Z MEDIUM
RANGE SOLUTIONS AND ENSEMBLES SUGGEST SOME DIGGING TROFFINESS IN THE
PACIFIC NORTHWEST/WESTERN CANADA TO TRANSLATE INTO PUMPED UP UPPER
RIDGING ACRS THE MID CONUS FRI INTO SAT. THUS WHILE THERMAL DOME
INTENSIFIES ACRS THE GRT BSN INTO THE SOUTHWESTERN PLAINS...MCS
TRACK/RING OF FIRE PATTERN TO ESTABLISH IN NORMAL DEEP SUMMER
LOCATION OF NORTHWESTERN HIGH PLAINS...UPPER MS RVR VALLEY...SOUTHERN
CANADA AND INTO THE GRT LKS. LATEST INDICATIONS SUGGEST A LESSENING
CHANCE FOR SOME OF THIS MCS ACTIVITY TO SPILL DOWN ACRS THE
NORTHERN CWA EITHER FRI NIGHT OR SAT NIGHT WHILE TEMPERATURES START
TO REBOUND BACK TO NORMAL OR EVEN WARMER. BY SUNDAY...WESTERLIES
FIRMLY ESTABLISH ACRS THE U.S.-CANADIAN BORDER REGION WITH UPPER
RIDGING DOMINATING ACRS THE SOUTHERN 2/3S OF THE CONUS. LONGER
RANGE THERMAL PROFILES SUGGEST ENOUGH AIRMASS MODIFICATION TO DRIVE
SUNDAY HIGHS UP INTO AT LEAST THE LOWER 90S ALONG WITH INCREASING
SFC DPTS/HUMIDITY. PASSING WAVE IN THIS PROGRESSIVE FLOW MAY TRY TO
SHUNT DOWN A WEAKENING SFC BOUNDARY DOWN TOWARD OR ACRS THE CWA
LATER SUNDAY NIGHT OR MONDAY AND GET SLOWED AS IT ALIGNS PARALLEL TO
MEAN STEERING FLOW. THUS THIS WINDOW MAY BE THE NEXT REAL CHANCE FOR
SOME PRECIP IN THE AREA AFTER TODAY/TONIGHT. LONGER RANGE SIGNALS ON
THE LATEST RUNS ESPECIALLY THE NEW 00Z ECMWF SUGGESTS THAT THIS
BROAD UPPER RIDGING PATTERN TO CONTINUE TO REIGN ACRS MUCH OF THE
CONUS WELL INTO MID NEXT WEEK...WHILE THE TROPICS CONTINUE TO GET
INTERESTING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 643 AM CDT TUE JUL 9 2013
SHOWERS AND STORMS WILL MOVE ACROSS THE AREA THROUGH EARLY AFTN
AFFECTING KCID...KDBQ AND KMLI TERMINALS. MVFR TO LOCAL IFR
CONDITIONS MAINLY FOR VSBYS 1-5SM WITH PCPN. HAVE VCSH WORDING
FURTHER SOUTH AT KBRL WITH LESS CERTAINTY ON COVERAGE AND IMPACT
TO TERMINAL. ANOTHER ROUND OF SHOWERS AND STORMS IS LIKELY LATE
THIS AFTERNOON AND TONIGHT AHEAD OF A COLD FRONT. STRONG TO SEVERE
WINDS COULD ACCOMPANY SOME OF THE STORMS. ADDITIONAL SHOWERS COULD
LINGER OVERNIGHT IN WAKE OF FRONTAL PASSAGE. LOW RISK OF MVFR CIGS
LATE TONIGHT WITH PROBABILITY APPEARING TOO LOW ATTM FOR INCLUSION
IN TAFS. OUTSIDE OF ANY STORMS... WINDS TODAY TO BECOME SSW AROUND
10 KTS AND MAY BE GUSTY AT TIMES. WINDS TO SHIFT TO NORTHWEST WITH
FRONTAL PASSAGE LATE TNGT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...ERVIN
SYNOPSIS...05
SHORT TERM...05
LONG TERM...12
AVIATION...05
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
750 AM CDT TUE JUL 9 2013
.UPDATE...
ISSUED AT 743 AM CDT TUE JUL 9 2013
SHOWERS AND STORMS ON MORE SCATTERED BASIS HAVE FILLED BACK IN
TO WESTERN IA. BASED ON THIS TREND CONCERN IS MOUNTING THAT WE
MAY JUST SEE OCCASIONAL SHOWERS AND STORMS ALL DAY. SHOULD THIS
OCCUR IT WOULD AID IN KEEPING HIGH TEMPS COOLER THAN FCST... AND
ALSO WOULD HAVE MAKE COVERAGE OF STORMS ALONG FRONT AND SEVERE
THREAT LATE AFTN/EVE MUCH MORE UNCERTAIN. NO MAJOR CHGS MADE WITH
7 AM UPDATE BUT WILL PASS ON CONCERNS TO NEXT SHIFT.
&&
.SYNOPSIS...
ISSUED AT 330 AM CDT TUE JUL 9 2013
06Z MSAS SFC ANALYSIS SUPPORTIVE OF WEAK LOW OVER CENTRAL SD WITH
STATIONARY FRONT EXTENDING SEWD FROM THE LOW AND BISECTING
EASTERN IA AND NORTHWEST IL. MOISTURE IS POOLING ALONG THE FRONT
WITH DEWPTS OF 70-75F. 00Z KDVN RAOB SHOWS DEEP MOISTURE WITH
PRECIPITABLE WATER VALUES OF NEARLY 2 INCHES... WHICH IS AROUND 160
PERCENT OF NORMAL AND NEARLY 2 STANDARD DEVIATIONS ABOVE THE MEAN.
CONVECTIVELY ENHANCED VORT MAX IS TRACKING THROUGH EASTERN NE ATTM
WITH RADARS SHOWING SHOWERS AND STORMS AHEAD OF THIS FEATURE INTO
WESTERN IA. ADDITIONAL COMPLEX OF STORMS WAS OVER THE DAKOTAS
AHEAD OF COLD FRONT AND SHORTWAVE MOVING EAST THROUGH FAR SOUTHERN
ALBERTA PROVINCE AND NORTHERN MT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CDT TUE JUL 9 2013
SUGGESTIONS OF 2 MAIN ROUNDS OF STORMS THROUGH THE PERIOD. AS
CONVECTIVELY ENHANCED VORT MAX MOVES EAST FROM NE ANTICIPATE
SHOWERS AND STORMS TRACKING AHEAD OF THIS FEATURE TO MOVE ACROSS
THE REGION BY MID AM THROUGH EARLY AFTN. PRIOR TO THE ARRIVAL
OF THESE STORMS COULD SEE ADDITIONAL DEVELOPMENT PRIOR TO MID AM
OVER THE AREA WITH WARM ADVECTION WING. POTENTIAL FOR SOME
STRENGTHENING OF MID LEVEL WINDS AND INTENSIFICATION OF STORMS
BY LATE AM AND AFTN FOR RISK OF FEW STRONG TO ISOLD SEVERE STORMS
WITH MOST RECENT RUNS OF HRRR 2-5KM UPDRAFT HELICITY AND 3 KM
VELOCITY CONTINUING TO SUGGEST THIS RISK NEAR AND ESPECIALLY NORTH
OF I-80. MAY SEE BREAK IN ACTION OR RELATIVE LULL IN ACTIVITY
BY MID-LATE AFTN WITH FOCUS SHIFTING BACK NORTHWEST FOR DEVELOPMENT
AHEAD OF COLD FRONT. LIKELY TO SEE ANOTHER ROUND OF STORMS MOVE
THROUGH THIS EVENING INTO OVERNIGHT AHEAD OF COLD FRONT.
STRENGTHENING 40-60 KT MID LEVEL SPEED MAX SPREADING BEHIND FRONT
COUPLED WITH VERY UNSTABLE ENVIRONMENT WILL SUPPORT RISK OF SEVERE
STORMS WITH POTENTIAL FOR UPSCALE GROWTH TO LINEAR MCS WITH MAINLY
DAMAGING WIND THREAT. HEAVY RAIN WILL BE A CONCERN AS WELL GIVEN
THE DEEP ALMOST TROPICAL MOISTURE IN PLACE. STORMS SHOULD BE MOVING
ALONG MORE THAN WE/VE SEEN OF LATE BUT WILL BE VERY EFFICIENT RAIN
PRODUCERS WITH RATES LIKELY 1-2"/HR. THUS... CANT RULE OUT SOME
LOCALIZED FLASH FLOODING AND WILL HAVE TO BE ESPECIALLY WATCHFULL
OVER PORTIONS OF DELAWARE AND DUBUQUE COUNTIES WHICH HAVE SEEN 2-5
INCHES PAST 24-36 HRS. EXPECT PCPN SHOULD BE DIMINISHING FROM NW
TO SE OVRNGT WITH PASSAGE OF COLD FRONT.
HIGHS TDY TRICKY WITH CLOUDS AND PCPN BUT OVERALL SHOULD RANGE FROM
MID 80S TO THE LOWER 90S. SOME MIXING OUT OF DEWPTS MAY OCCUR BUT
AT LEAST UPPER 60S TO LOWER 70S EXPECTED ON DEWPTS... WHICH COMBINED
WITH TEMPS WILL MAKE FOR HEAT INDICES MAINLY IN THE MID TO UPPER 90S.
COOLER AND DRIER AIR LAGS BEHIND FRONT TNGT... THUS LOWS ONLY DROP
INTO THE UPPER 60S TO LOWER 70S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 330 AM CDT TUE JUL 9 2013
WEDNESDAY AND THURSDAY...AS L/W TROF CONTINUES TO DEEPEN AND
ESTABLISH ACRS THE GRT LKS...SEASONABLY STRONG LLVL HIGH PRESSURE
WILL LOOK TO DUMP DOWN THE NORTHERN PLAINS AND MO RVR VALLEY ON WED.
A FEW POST-FRONTAL SHOWERS AND STORMS MAY BE OCCURRING ACRS THE FAR
EASTERN/SOUTHERN CWA WED MORNING BUT BULK OF THE ACTIVITY SHOULD BE
GONE BY 15Z. VEERING AND INCREASING BOUNDARY LAYER FLOW AS WELL AS
INCOMING SUBSIDENCE SHOULD CLEAR THINGS OUT ON WED...BUT SOME LAG IN
CAA TO ALLOW TEMPS TO WARM INTO THE LOW TO MID 80S EVEN POST-
FRONTALLY. A RATHER BREEZY NORTHWEST TO NORTH WIND OF 15-20 MPH.
CLEAR SKIES AND WIND DROP OFF WED NIGHT TO ALLOW SOME AREA TEMPS TO
DROP OFF INTO THE 50S. LLVL HIGH PRESSURE CONTINUING TO MIGRATE
EASTWARD ACRS THE REGION TO MAKE FOR A CHAMBER OF COMMERCE DAY THU
WITH HIGHS IN THE UPPER 70S TO LOWER 80S...SUNSHINE AND LOWER
HUMIDITY. THU NIGHT SEASONABLY COOL AGAIN WITH LOWS IN THE 50S AND
LOW 60S.
FRIDAY THROUGH NEXT MONDAY...TRENDS OF THE LATEST RUN 00Z MEDIUM
RANGE SOLUTIONS AND ENSEMBLES SUGGEST SOME DIGGING TROFFINESS IN THE
PACIFIC NORTHWEST/WESTERN CANADA TO TRANSLATE INTO PUMPED UP UPPER
RIDGING ACRS THE MID CONUS FRI INTO SAT. THUS WHILE THERMAL DOME
INTENSIFIES ACRS THE GRT BSN INTO THE SOUTHWESTERN PLAINS...MCS
TRACK/RING OF FIRE PATTERN TO ESTABLISH IN NORMAL DEEP SUMMER
LOCATION OF NORTHWESTERN HIGH PLAINS...UPPER MS RVR VALLEY...SOUTHERN
CANADA AND INTO THE GRT LKS. LATEST INDICATIONS SUGGEST A LESSENING
CHANCE FOR SOME OF THIS MCS ACTIVITY TO SPILL DOWN ACRS THE
NORTHERN CWA EITHER FRI NIGHT OR SAT NIGHT WHILE TEMPERATURES START
TO REBOUND BACK TO NORMAL OR EVEN WARMER. BY SUNDAY...WESTERLIES
FIRMLY ESTABLISH ACRS THE U.S.-CANADIAN BORDER REGION WITH UPPER
RIDGING DOMINATING ACRS THE SOUTHERN 2/3S OF THE CONUS. LONGER
RANGE THERMAL PROFILES SUGGEST ENOUGH AIRMASS MODIFICATION TO DRIVE
SUNDAY HIGHS UP INTO AT LEAST THE LOWER 90S ALONG WITH INCREASING
SFC DPTS/HUMIDITY. PASSING WAVE IN THIS PROGRESSIVE FLOW MAY TRY TO
SHUNT DOWN A WEAKENING SFC BOUNDARY DOWN TOWARD OR ACRS THE CWA
LATER SUNDAY NIGHT OR MONDAY AND GET SLOWED AS IT ALIGNS PARALLEL TO
MEAN STEERING FLOW. THUS THIS WINDOW MAY BE THE NEXT REAL CHANCE FOR
SOME PRECIP IN THE AREA AFTER TODAY/TONIGHT. LONGER RANGE SIGNALS ON
THE LATEST RUNS ESPECIALLY THE NEW 00Z ECMWF SUGGESTS THAT THIS
BROAD UPPER RIDGING PATTERN TO CONTINUE TO REIGN ACRS MUCH OF THE
CONUS WELL INTO MID NEXT WEEK...WHILE THE TROPICS CONTINUE TO GET
INTERESTING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 643 AM CDT TUE JUL 9 2013
SHOWERS AND STORMS WILL MOVE ACROSS THE AREA THROUGH EARLY AFTN
AFFECTING KCID...KDBQ AND KMLI TERMINALS. MVFR TO LOCAL IFR
CONDITIONS MAINLY FOR VSBYS 1-5SM WITH PCPN. HAVE VCSH WORDING
FURTHER SOUTH AT KBRL WITH LESS CERTAINTY ON COVERAGE AND IMPACT
TO TERMINAL. ANOTHER ROUND OF SHOWERS AND STORMS IS LIKELY LATE
THIS AFTERNOON AND TONIGHT AHEAD OF A COLD FRONT. STRONG TO SEVERE
WINDS COULD ACCOMPANY SOME OF THE STORMS. ADDITIONAL SHOWERS COULD
LINGER OVERNIGHT IN WAKE OF FRONTAL PASSAGE. LOW RISK OF MVFR CIGS
LATE TONIGHT WITH PROBABILITY APPEARING TOO LOW ATTM FOR INCLUSION
IN TAFS. OUTSIDE OF ANY STORMS... WINDS TODAY TO BECOME SSW AROUND
10 KTS AND MAY BE GUSTY AT TIMES. WINDS TO SHIFT TO NORTHWEST WITH
FRONTAL PASSAGE LATE TNGT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...05
SYNOPSIS...05
SHORT TERM...05
LONG TERM...12
AVIATION...05
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
658 AM CDT TUE JUL 9 2013
.SYNOPSIS...
ISSUED AT 330 AM CDT TUE JUL 9 2013
06Z MSAS SFC ANALYSIS SUPPORTIVE OF WEAK LOW OVER CENTRAL SD WITH
STATIONARY FRONT EXTENDING SEWD FROM THE LOW AND BISECTING
EASTERN IA AND NORTHWEST IL. MOISTURE IS POOLING ALONG THE FRONT
WITH DEWPTS OF 70-75F. 00Z KDVN RAOB SHOWS DEEP MOISTURE WITH
PRECIPITABLE WATER VALUES OF NEARLY 2 INCHES... WHICH IS AROUND 160
PERCENT OF NORMAL AND NEARLY 2 STANDARD DEVIATIONS ABOVE THE MEAN.
CONVECTIVELY ENHANCED VORT MAX IS TRACKING THROUGH EASTERN NE ATTM
WITH RADARS SHOWING SHOWERS AND STORMS AHEAD OF THIS FEATURE INTO
WESTERN IA. ADDITIONAL COMPLEX OF STORMS WAS OVER THE DAKOTAS
AHEAD OF COLD FRONT AND SHORTWAVE MOVING EAST THROUGH FAR SOUTHERN
ALBERTA PROVINCE AND NORTHERN MT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CDT TUE JUL 9 2013
SUGGESTIONS OF 2 MAIN ROUNDS OF STORMS THROUGH THE PERIOD. AS
CONVECTIVELY ENHANCED VORT MAX MOVES EAST FROM NE ANTICIPATE
SHOWERS AND STORMS TRACKING AHEAD OF THIS FEATURE TO MOVE ACROSS
THE REGION BY MID AM THROUGH EARLY AFTN. PRIOR TO THE ARRIVAL
OF THESE STORMS COULD SEE ADDITIONAL DEVELOPMENT PRIOR TO MID AM
OVER THE AREA WITH WARM ADVECTION WING. POTENTIAL FOR SOME
STRENGTHENING OF MID LEVEL WINDS AND INTENSIFICATION OF STORMS
BY LATE AM AND AFTN FOR RISK OF FEW STRONG TO ISOLD SEVERE STORMS
WITH MOST RECENT RUNS OF HRRR 2-5KM UPDRAFT HELICITY AND 3 KM
VELOCITY CONTINUING TO SUGGEST THIS RISK NEAR AND ESPECIALLY NORTH
OF I-80. MAY SEE BREAK IN ACTION OR RELATIVE LULL IN ACTIVITY
BY MID-LATE AFTN WITH FOCUS SHIFTING BACK NORTHWEST FOR DEVELOPMENT
AHEAD OF COLD FRONT. LIKELY TO SEE ANOTHER ROUND OF STORMS MOVE
THROUGH THIS EVENING INTO OVERNIGHT AHEAD OF COLD FRONT.
STRENGTHENING 40-60 KT MID LEVEL SPEED MAX SPREADING BEHIND FRONT
COUPLED WITH VERY UNSTABLE ENVIRONMENT WILL SUPPORT RISK OF SEVERE
STORMS WITH POTENTIAL FOR UPSCALE GROWTH TO LINEAR MCS WITH MAINLY
DAMAGING WIND THREAT. HEAVY RAIN WILL BE A CONCERN AS WELL GIVEN
THE DEEP ALMOST TROPICAL MOISTURE IN PLACE. STORMS SHOULD BE MOVING
ALONG MORE THAN WE/VE SEEN OF LATE BUT WILL BE VERY EFFICIENT RAIN
PRODUCERS WITH RATES LIKELY 1-2"/HR. THUS... CANT RULE OUT SOME
LOCALIZED FLASH FLOODING AND WILL HAVE TO BE ESPECIALLY WATCHFULL
OVER PORTIONS OF DELAWARE AND DUBUQUE COUNTIES WHICH HAVE SEEN 2-5
INCHES PAST 24-36 HRS. EXPECT PCPN SHOULD BE DIMINISHING FROM NW
TO SE OVRNGT WITH PASSAGE OF COLD FRONT.
HIGHS TDY TRICKY WITH CLOUDS AND PCPN BUT OVERALL SHOULD RANGE FROM
MID 80S TO THE LOWER 90S. SOME MIXING OUT OF DEWPTS MAY OCCUR BUT
AT LEAST UPPER 60S TO LOWER 70S EXPECTED ON DEWPTS... WHICH COMBINED
WITH TEMPS WILL MAKE FOR HEAT INDICES MAINLY IN THE MID TO UPPER 90S.
COOLER AND DRIER AIR LAGS BEHIND FRONT TNGT... THUS LOWS ONLY DROP
INTO THE UPPER 60S TO LOWER 70S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 330 AM CDT TUE JUL 9 2013
WEDNESDAY AND THURSDAY...AS L/W TROF CONTINUES TO DEEPEN AND
ESTABLISH ACRS THE GRT LKS...SEASONABLY STRONG LLVL HIGH PRESSURE
WILL LOOK TO DUMP DOWN THE NORTHERN PLAINS AND MO RVR VALLEY ON WED.
A FEW POST-FRONTAL SHOWERS AND STORMS MAY BE OCCURRING ACRS THE FAR
EASTERN/SOUTHERN CWA WED MORNING BUT BULK OF THE ACTIVITY SHOULD BE
GONE BY 15Z. VEERING AND INCREASING BOUNDARY LAYER FLOW AS WELL AS
INCOMING SUBSIDENCE SHOULD CLEAR THINGS OUT ON WED...BUT SOME LAG IN
CAA TO ALLOW TEMPS TO WARM INTO THE LOW TO MID 80S EVEN POST-
FRONTALLY. A RATHER BREEZY NORTHWEST TO NORTH WIND OF 15-20 MPH.
CLEAR SKIES AND WIND DROP OFF WED NIGHT TO ALLOW SOME AREA TEMPS TO
DROP OFF INTO THE 50S. LLVL HIGH PRESSURE CONTINUING TO MIGRATE
EASTWARD ACRS THE REGION TO MAKE FOR A CHAMBER OF COMMERCE DAY THU
WITH HIGHS IN THE UPPER 70S TO LOWER 80S...SUNSHINE AND LOWER
HUMIDITY. THU NIGHT SEASONABLY COOL AGAIN WITH LOWS IN THE 50S AND
LOW 60S.
FRIDAY THROUGH NEXT MONDAY...TRENDS OF THE LATEST RUN 00Z MEDIUM
RANGE SOLUTIONS AND ENSEMBLES SUGGEST SOME DIGGING TROFFINESS IN THE
PACIFIC NORTHWEST/WESTERN CANADA TO TRANSLATE INTO PUMPED UP UPPER
RIDGING ACRS THE MID CONUS FRI INTO SAT. THUS WHILE THERMAL DOME
INTENSIFIES ACRS THE GRT BSN INTO THE SOUTHWESTERN PLAINS...MCS
TRACK/RING OF FIRE PATTERN TO ESTABLISH IN NORMAL DEEP SUMMER
LOCATION OF NORTHWESTERN HIGH PLAINS...UPPER MS RVR VALLEY...SOUTHERN
CANADA AND INTO THE GRT LKS. LATEST INDICATIONS SUGGEST A LESSENING
CHANCE FOR SOME OF THIS MCS ACTIVITY TO SPILL DOWN ACRS THE
NORTHERN CWA EITHER FRI NIGHT OR SAT NIGHT WHILE TEMPERATURES START
TO REBOUND BACK TO NORMAL OR EVEN WARMER. BY SUNDAY...WESTERLIES
FIRMLY ESTABLISH ACRS THE U.S.-CANADIAN BORDER REGION WITH UPPER
RIDGING DOMINATING ACRS THE SOUTHERN 2/3S OF THE CONUS. LONGER
RANGE THERMAL PROFILES SUGGEST ENOUGH AIRMASS MODIFICATION TO DRIVE
SUNDAY HIGHS UP INTO AT LEAST THE LOWER 90S ALONG WITH INCREASING
SFC DPTS/HUMIDITY. PASSING WAVE IN THIS PROGRESSIVE FLOW MAY TRY TO
SHUNT DOWN A WEAKENING SFC BOUNDARY DOWN TOWARD OR ACRS THE CWA
LATER SUNDAY NIGHT OR MONDAY AND GET SLOWED AS IT ALIGNS PARALLEL TO
MEAN STEERING FLOW. THUS THIS WINDOW MAY BE THE NEXT REAL CHANCE FOR
SOME PRECIP IN THE AREA AFTER TODAY/TONIGHT. LONGER RANGE SIGNALS ON
THE LATEST RUNS ESPECIALLY THE NEW 00Z ECMWF SUGGESTS THAT THIS
BROAD UPPER RIDGING PATTERN TO CONTINUE TO REIGN ACRS MUCH OF THE
CONUS WELL INTO MID NEXT WEEK...WHILE THE TROPICS CONTINUE TO GET
INTERESTING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 643 AM CDT TUE JUL 9 2013
SHOWERS AND STORMS WILL MOVE ACROSS THE AREA THROUGH EARLY AFTN
AFFECTING KCID...KDBQ AND KMLI TERMINALS. MVFR TO LOCAL IFR
CONDITIONS MAINLY FOR VSBYS 1-5SM WITH PCPN. HAVE VCSH WORDING
FURTHER SOUTH AT KBRL WITH LESS CERTAINTY ON COVERAGE AND IMPACT
TO TERMINAL. ANOTHER ROUND OF SHOWERS AND STORMS IS LIKELY LATE
THIS AFTERNOON AND TONIGHT AHEAD OF A COLD FRONT. STRONG TO SEVERE
WINDS COULD ACCOMPANY SOME OF THE STORMS. ADDITIONAL SHOWERS COULD
LINGER OVERNIGHT IN WAKE OF FRONTAL PASSAGE. LOW RISK OF MVFR CIGS
LATE TONIGHT WITH PROBABILITY APPEARING TOO LOW ATTM FOR INCLUSION
IN TAFS. OUTSIDE OF ANY STORMS... WINDS TODAY TO BECOME SSW AROUND
10 KTS AND MAY BE GUSTY AT TIMES. WINDS TO SHIFT TO NORTHWEST WITH
FRONTAL PASSAGE LATE TNGT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...05
SHORT TERM...05
LONG TERM...12
AVIATION...05
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
401 AM CDT TUE JUL 9 2013
.SYNOPSIS...
ISSUED AT 330 AM CDT TUE JUL 9 2013
06Z MSAS SFC ANALYSIS SUPPORTIVE OF WEAK LOW OVER CENTRAL SD WITH
STATIONARY FRONT EXTENDING SEWD FROM THE LOW AND BISECTING
EASTERN IA AND NORTHWEST IL. MOISTURE IS POOLING ALONG THE FRONT
WITH DEWPTS OF 70-75F. 00Z KDVN RAOB SHOWS DEEP MOISTURE WITH
PRECIPITABLE WATER VALUES OF NEARLY 2 INCHES... WHICH IS AROUND 160
PERCENT OF NORMAL AND NEARLY 2 STANDARD DEVIATIONS ABOVE THE MEAN.
CONVECTIVELY ENHANCED VORT MAX IS TRACKING THROUGH EASTERN NE ATTM
WITH RADARS SHOWING SHOWERS AND STORMS AHEAD OF THIS FEATURE INTO
WESTERN IA. ADDITIONAL COMPLEX OF STORMS WAS OVER THE DAKOTAS
AHEAD OF COLD FRONT AND SHORTWAVE MOVING EAST THROUGH FAR SOUTHERN
ALBERTA PROVINCE AND NORTHERN MT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CDT TUE JUL 9 2013
SUGGESTIONS OF 2 MAIN ROUNDS OF STORMS THROUGH THE PERIOD. AS
CONVECTIVELY ENHANCED VORT MAX MOVES EAST FROM NE ANTICIPATE
SHOWERS AND STORMS TRACKING AHEAD OF THIS FEATURE TO MOVE ACROSS
THE REGION BY MID AM THROUGH EARLY AFTN. PRIOR TO THE ARRIVAL
OF THESE STORMS COULD SEE ADDITIONAL DEVELOPMENT PRIOR TO MID AM
OVER THE AREA WITH WARM ADVECTION WING. POTENTIAL FOR SOME
STRENGTHENING OF MID LEVEL WINDS AND INTENSIFICATION OF STORMS
BY LATE AM AND AFTN FOR RISK OF FEW STRONG TO ISOLD SEVERE STORMS
WITH MOST RECENT RUNS OF HRRR 2-5KM UPDRAFT HELICITY AND 3 KM
VELOCITY CONTINUING TO SUGGEST THIS RISK NEAR AND ESPECIALLY NORTH
OF I-80. MAY SEE BREAK IN ACTION OR RELATIVE LULL IN ACTIVITY
BY MID-LATE AFTN WITH FOCUS SHIFTING BACK NORTHWEST FOR DEVELOPMENT
AHEAD OF COLD FRONT. LIKELY TO SEE ANOTHER ROUND OF STORMS MOVE
THROUGH THIS EVENING INTO OVERNIGHT AHEAD OF COLD FRONT.
STRENGTHENING 40-60 KT MID LEVEL SPEED MAX SPREADING BEHIND FRONT
COUPLED WITH VERY UNSTABLE ENVIRONMENT WILL SUPPORT RISK OF SEVERE
STORMS WITH POTENTIAL FOR UPSCALE GROWTH TO LINEAR MCS WITH MAINLY
DAMAGING WIND THREAT. HEAVY RAIN WILL BE A CONCERN AS WELL GIVEN
THE DEEP ALMOST TROPICAL MOISTURE IN PLACE. STORMS SHOULD BE MOVING
ALONG MORE THAN WE/VE SEEN OF LATE BUT WILL BE VERY EFFICIENT RAIN
PRODUCERS WITH RATES LIKELY 1-2"/HR. THUS... CANT RULE OUT SOME
LOCALIZED FLASH FLOODING AND WILL HAVE TO BE ESPECIALLY WATCHFULL
OVER PORTIONS OF DELAWARE AND DUBUQUE COUNTIES WHICH HAVE SEEN 2-5
INCHES PAST 24-36 HRS. EXPECT PCPN SHOULD BE DIMINISHING FROM NW
TO SE OVRNGT WITH PASSAGE OF COLD FRONT.
HIGHS TDY TRICKY WITH CLOUDS AND PCPN BUT OVERALL SHOULD RANGE FROM
MID 80S TO THE LOWER 90S. SOME MIXING OUT OF DEWPTS MAY OCCUR BUT
AT LEAST UPPER 60S TO LOWER 70S EXPECTED ON DEWPTS... WHICH COMBINED
WITH TEMPS WILL MAKE FOR HEAT INDICES MAINLY IN THE MID TO UPPER 90S.
COOLER AND DRIER AIR LAGS BEHIND FRONT TNGT... THUS LOWS ONLY DROP
INTO THE UPPER 60S TO LOWER 70S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 330 AM CDT TUE JUL 9 2013
WEDNESDAY AND THURSDAY...AS L/W TROF CONTINUES TO DEEPEN AND
ESTABLISH ACRS THE GRT LKS...SEASONABLY STRONG LLVL HIGH PRESSURE
WILL LOOK TO DUMP DOWN THE NORTHERN PLAINS AND MO RVR VALLEY ON WED.
A FEW POST-FRONTAL SHOWERS AND STORMS MAY BE OCCURRING ACRS THE FAR
EASTERN/SOUTHERN CWA WED MORNING BUT BULK OF THE ACTIVITY SHOULD BE
GONE BY 15Z. VEERING AND INCREASING BOUNDARY LAYER FLOW AS WELL AS
INCOMING SUBSIDENCE SHOULD CLEAR THINGS OUT ON WED...BUT SOME LAG IN
CAA TO ALLOW TEMPS TO WARM INTO THE LOW TO MID 80S EVEN POST-
FRONTALLY. A RATHER BREEZY NORTHWEST TO NORTH WIND OF 15-20 MPH.
CLEAR SKIES AND WIND DROP OFF WED NIGHT TO ALLOW SOME AREA TEMPS TO
DROP OFF INTO THE 50S. LLVL HIGH PRESSURE CONTINUING TO MIGRATE
EASTWARD ACRS THE REGION TO MAKE FOR A CHAMBER OF COMMERCE DAY THU
WITH HIGHS IN THE UPPER 70S TO LOWER 80S...SUNSHINE AND LOWER
HUMIDITY. THU NIGHT SEASONABLY COOL AGAIN WITH LOWS IN THE 50S AND
LOW 60S.
FRIDAY THROUGH NEXT MONDAY...TRENDS OF THE LATEST RUN 00Z MEDIUM
RANGE SOLUTIONS AND ENSEMBLES SUGGEST SOME DIGGING TROFFINESS IN THE
PACIFIC NORTHWEST/WESTERN CANADA TO TRANSLATE INTO PUMPED UP UPPER
RIDGING ACRS THE MID CONUS FRI INTO SAT. THUS WHILE THERMAL DOME
INTENSIFIES ACRS THE GRT BSN INTO THE SOUTHWESTERN PLAINS...MCS
TRACK/RING OF FIRE PATTERN TO ESTABLISH IN NORMAL DEEP SUMMER
LOCATION OF NORTHWESTERN HIGH PLAINS...UPPER MS RVR VALLEY...SOUTHERN
CANADA AND INTO THE GRT LKS. LATEST INDICATIONS SUGGEST A LESSENING
CHANCE FOR SOME OF THIS MCS ACTIVITY TO SPILL DOWN ACRS THE
NORTHERN CWA EITHER FRI NIGHT OR SAT NIGHT WHILE TEMPERATURES START
TO REBOUND BACK TO NORMAL OR EVEN WARMER. BY SUNDAY...WESTERLIES
FIRMLY ESTABLISH ACRS THE U.S.-CANADIAN BORDER REGION WITH UPPER
RIDGING DOMINATING ACRS THE SOUTHERN 2/3S OF THE CONUS. LONGER
RANGE THERMAL PROFILES SUGGEST ENOUGH AIRMASS MODIFICATION TO DRIVE
SUNDAY HIGHS UP INTO AT LEAST THE LOWER 90S ALONG WITH INCREASING
SFC DPTS/HUMIDITY. PASSING WAVE IN THIS PROGRESSIVE FLOW MAY TRY TO
SHUNT DOWN A WEAKENING SFC BOUNDARY DOWN TOWARD OR ACRS THE CWA
LATER SUNDAY NIGHT OR MONDAY AND GET SLOWED AS IT ALIGNS PARALLEL TO
MEAN STEERING FLOW. THUS THIS WINDOW MAY BE THE NEXT REAL CHANCE FOR
SOME PRECIP IN THE AREA AFTER TODAY/TONIGHT. LONGER RANGE SIGNALS ON
THE LATEST RUNS ESPECIALLY THE NEW 00Z ECMWF SUGGESTS THAT THIS
BROAD UPPER RIDGING PATTERN TO CONTINUE TO REIGN ACRS MUCH OF THE
CONUS WELL INTO MID NEXT WEEK...WHILE THE TROPICS CONTINUE TO GET
INTERESTING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1135 PM CDT MON JUL 8 2013
LIGHT WINDS AND SUMMER HUMIDITY WILL LIKELY LEAD TO FOG
DEVELOPMENT TONIGHT AND FOR NOW WILL ANTICIPATE MID LEVEL CLOUD
COVER TO PREVENT VISIBILITIES FROM DROPPING ANY LOWER THAN 4 OR 5
MILES LATE TONIGHT. THERE REMAINS A CHANCE FOR ISOLATED TO WIDELY
SCATTERED THUNDERSTORMS TONIGHT THROUGH TUESDAY NIGHT. THE BEST
CHANCES WILL BE CENTERED ALONG AND AHEAD OF A COLD FRONT THAT WILL
DROP THROUGH THE AREA TUESDAY EVENING. AHEAD OF THIS...HAVE GONE
WITH LOW CONFIDENCE PROB30 OR VCTS WORDING TO COVER THE
POTENTIAL. WINDS WILL BE LIGHT AND PRIMARILY FROM THE SOUTH TO
SOUTHWEST THROUGHOUT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...05
SHORT TERM...05
LONG TERM...12
AVIATION...SHEETS
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
302 PM CDT TUE JUL 9 2013
...UPDATED SHORT TERM...
.SYNOPSIS...
ISSUED AT 300 PM CDT TUE JUL 9 2013
ON THE SYNOPTIC SCALE, A MUCH MORE ZONAL FLOW HAS DEVELOPED ACROSS
THE CONUS WITH A POLAR JET FOCUSES ACROSS THE NORTHERN STATES, AND
A BROAD MID LEVEL SHORTWAVE EMBEDDED IN THE FLOW ACROSS EASTERN
MONTANA. TEMPERATURES WARMED INTO THE UPPER 80S TO AROUND 90 DEGREES
BY 11 AM ACROSS SOUTHWEST AND SOUTH CENTRAL KANSAS. TEMPERATURES
WERE SLIGHTLY SLOWER TO RESPOND ACROSS SECTIONS OF WEST CENTRAL
KANSAS WHERE BANDS OF MID LEVEL STRATOCUMULUS WERE PRESENT. THIS
PATTERN INCLUDES A FLATTENING OF THE UPPER ANTICYCLONE NOW LOCATED
FROM THE DESERT SOUTHWEST INTO THE SOUTHERN PLAINS. THE 12 UTC 700
MB ANALYSIS SHOWED A WARM PLUME OF MID LEVEL AIR ACROSS EASTERN
COLORADO AND WESTERN KANSAS AS WARM AS 15 DEGREES C. THE 850 MB
LEVEL TROUGH WHICH EXTENDED ACROSS THE NORTHERN AND CENTRAL HIGH
PLAINS CREATED A DOWNSLOPE SURFACE WIND FIELD OVER SOUTHWEST AND
CENTRAL KANSAS WITH TEMPERATURES IN THE UPPER 20`S C. AT THE SURFACE,
A BETTER IDENTIFIED COLD FRONT BASED ON SURFACE MOISTURE
DISCONTINUITY EXTENDED ACROSS WESTERN NEBRASKA THROUGH THE EASTERN
DAKOTAS, WHILE AN AREA OF LOW PRESSURE AHEAD OF THE BOUNDARY
EXHIBITED ANS ATTENDANT TROUGH FROM CENTRAL NEBRASKA INTO WEST
CENTRAL KANSAS. JUST AHEAD OF THE SURFACE TROUGH, DEW POINTS OF 60
TO 65 DEGREES CONTRIBUTED TO PRECIPITABLE WATER VALUES IN EXCESS OF
AN INCH AND A HALF THROUGH THE INTERSTATE 70 AND HIGHWAY 156
CORRIDORS.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 300 PM CDT TUE JUL 9 2013
THE HEAT AND CONVECTIVE CHANCES INCLUDING POTENTIAL IMPACTS ARE THE
MAIN FORECAST ISSUES EARLY IN THE SHORT TERM. THE HEAT ADVISORY WILL
BE MAINTAINED IN IT`S CURRENT CONFIGURATION ALTHOUGH THE WESTERN
PERIPHERY MAY BE SUSPECT TO MEETING LOW END ADVISORY CRITERIA DUE TO
SURFACE DEW POINTS THAT HAVE MIXED OUT INTO THE MID/UPPER 50`S. IF
THE TREND CONTINUES INTO EARLY AFTERNOON, IN EFFECT TEMPERATURES
ALSO ARE NOT TRENDING AS WARM AS FORECAST, SOME AREAS ALONG THE
WESTERN PERIPHERY MAY NEED TO BE TRIMMED FROM THE ADVISORY.
THE NAM/ WRF NMM AND ARW ALL DEVELOP CONVECTION ALONG THE FRONTAL
BOUNDARY EXTENDING INTO NORTHWEST KANSAS THIS AFTERNOON. SIGNIFICANT
DIFFERENCES IN COVERAGE EXISTS BETWEEN THE MODELS, VARYING FROM
RATHER ISOLATED CLUSTERS TO MORE ORGANIZED LINE SEGMENTS WITH
PROLIFIC OUTFLOW. THE HRRR IS PARTICULARLY AGGRESSIVE WITH
DEVELOPING HEAVY QPF AND RAIN COOLED OUTFLOW OF 30 KNOTS LOCALLY
RIGHT AHEAD OF THE FRONT ALONG THE MAXIMUM DEW POINT AND PWAT
GRADIENT. HOWEVER THE WEATHER EVOLVES THIS AFTERNOON AND EVENING
MAY HAVE AN IMPACT ON TEMPERATURES AND CONVECTIVE CHANCES AGAIN ON
WEDNESDAY AFTERNOON. HOWEVER, THE BETTER CHANCE FOR CONVECTION ON
WEDNESDAY WILL LIKELY OCCUR DUE TO DIFFERENTIAL HEATING OVER THE
HIGHER TERRAIN OF EASTERN COLORADO, INCREASING CHANCES ACROSS
WESTERN KANSAS INTO WEDNESDAY EVENING. HIGHS WEDNESDAY WILL BE
AROUND 10 DEGREES COOLER BEHIND THE BOUNDARY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 215 PM CDT TUE JUL 9 2013
A WARM AND FAIRLY DRY PERIOD BEGINS AFTER WEDNESDAY NIGHT AS A LARGE
RIDGE OF UPPER LEVEL HIGH PRESSURE BUILDS INTO THE PLAINS.
FOR WEDNESDAY NIGHT WILL MAINTAIN A 30 TO 40 PERCENT CHANCE OF
THUNDERSTORMS JUST NORTH OF A WEAK FRONTAL BOUNDARY IN MOIST UPSLOPE
REGIME ACROSS MUCH OF WESTERN KANSAS. THIS WILL BE OUR BEST CHANCE
OF SEEING MEASURABLE RAINFALL INTO NEXT WEEK. WITH WEAK WINDS ALOFT
NOT EXPECTING SEVERE WEATHER. THERE COULD BE SOME LOCALLY HEAVY
DOWNPOURS IF STORMS GET GOING AND THEY ARE SLOW MOVING.
A WESTWARD MOVING UPPER LOW BEGINS TO UNDERCUT THE RIDGE ACROSS THE
SOUTHERN AND CENTRAL PLAINS FROM SUNDAY INTO TUESDAY WITH A SLIGHT
CHANCE OF THUNDERSTORMS ON MONDAY NEAR A CONVERGENCE LINE, ALONG
WITH SLIGHTLY COOLER TEMPERATURES.
OVERNIGHT LOWS WILL BE MILD AROUND 70 TO 75 THROUGH THE PERIOD.
DAYTIME HIGHS WARM BACK TO AROUND 100 TO 105 ON FRIDAY AND SATURDAY
THEN COOL SLIGHTLY BACK INTO THE MID TO UPPER 90S INTO NEXT TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 200 PM CDT TUE JUL 9 2013
WITH THE EXCEPTION OF THE POSSIBILITY OF SEVERE CONVECTION PRODUCING
40 TO 50 KNOT WIND GUSTS LATE THIS AFTERNOON AND EARLY EVENING, THE
AREA INCLUDING THE LOCAL TERMINALS WILL BE UNDER VFR CONDITIONS.
CONVECTION MAY DEVELOP ALONG A SURFACE FRONT NORTHWEST OF HAYS
BETWEEN 21 AND 00 UTC. THE ATMOSPHERE IS CONDUCIVE TO PRODUCING
WIDESPREAD THUNDERSTORMS OUTFLOW, WITH LOCALLY SEVERE GUSTS IN A
ONE TO TWO HOUR EPISODE ENDING IN THE EARLY EVENING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 72 97 70 98 / 40 30 30 10
GCK 71 95 69 99 / 40 30 30 10
EHA 71 96 69 101 / 20 30 30 10
LBL 72 98 70 102 / 30 30 30 10
HYS 72 94 69 95 / 40 20 20 20
P28 76 100 72 97 / 40 20 20 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR KSZ030-031-044>046-
064>066-078>081-088>090.
&&
$$
SYNOPSIS...RUSSELL
SHORT TERM...RUSSELL
LONG TERM...KRUSE
AVIATION...RUSSELL
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
946 PM EDT WED JUL 10 2013
.UPDATE...
ISSUED AT 945 PM EDT WED JUL 10 2013
THUNDERSTORMS ARE OVER AND SHOWERS ARE DIMINISHING. PCPN HAS BECOME
MORE SCT IN NATURE AND WILL REDUCE POPS FOR THE OVERNIGHT. COLD FRONT
STILL PRESSING TO THE SE ACROSS THE OHIO RIVER BUT IT IS INDICATED BY
A THIN LINE OF WIDELY DISPERSED CONVECTION. TEMPS ON TRACK BUT THE
FOG IS MORE WIDESPREAD THAN PREVIOUS FCST AND IS EVEN SOME LOW
STRATUS AT JKL REDUCING CIG AND VSBY.
UPDATE ISSUED AT 710 PM EDT WED JUL 10 2013
THUNDERSTORMS HAVE DIMINISHED IN INTENSITY AND COVERAGE. HEAVY RAIN
IS OVER AND WILL ELIMINATE BOTH THE SVR THUNDERSTORM WATCH 407 AND
THE FLASH FLOOD WATCH.
UPDATE ISSUED AT 600 PM EDT WED JUL 10 2013
HAVE HAD ONLY 1 REPORT OF WIND DAMAGE SO FAR...AND SEVERE THREAT IS
DIMINISHING. WILL BE UPDATING NDFD FOR LATEST OBSERVATIONAL TRENDS
AND FOR CURRENT MOVEMENT OF SHOWERS AND THUNDERSTORMS ACROSS THE
FORECAST AREA. PLAN TO BEGIN TRIMMING COUNTIES FROM THE SEVERE
THUNDERSTORM WATCH ON THE WESTERN PART OF THE FORECAST AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 304 PM EDT WED JUL 10 2013
WILL ADD PIKE...LETCHER AND HARLAN COUNTY TO FLASH FLOOD WATCH.
WITH CONVECTION IN THESE AREAS ALREADY OCCURRING TODAY...THEY WILL BE
PRIMED FOR POTENTIAL FLASH FLOODING WITH ADDITIONAL ACTIVITY THIS
EVENING AND OVERNIGHT. COLD FRONT CURRENTLY IN NORTHWEST INDIANA WILL
BE ONLY SLOWLY PRESSING SOUTHEAST OVERNIGHT AND NOT CLEARING
SOUTHEAST KY UNTIL THURSDAY AFTERNOON. LATEST MODEL GUIDANCE AND
ESPECIALLY CURRENT RADAR TRENDS POINTING TOWARDS MULTIPLE ROUNDS OF
SHOWERS AND THUNDERSTORMS FROM LATE THIS AFTERNOON INTO TONIGHT.
PRECIPITABLE WATER AROUND 1.8 THIS AFTERNOON AND WILL NOT SEE MUCH
DECREASE UNTIL AFTER FRONTAL PASSAGE ON THURSDAY...AND THUNDERSTORMS
WILL CONTINUE TO BE CAPABLE OF PRODUCING VERY HEAVY RAIN.
CONSIDERABLE DESTABILIZATION HAS OCCURRED THIS AFTERNOON AND SEVERE
THREAT ALSO INCREASING...WITH SEVERE REPORTS ALREADY OCCURRING IN
CENTRAL KY. HRRR IS POINTING TOWARDS ACTIVITY OVER CENTRAL KY MERGING
INTO A BOWING LINE WHICH WOULD INCREASE SEVERE THREAT OVER SE KY
EARLY THIS EVENING.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 334 PM EDT WED JUL 10 2013
THERE IS DECENT AGREEMENT WITH THE VARIOUS MODELS HOWEVER THERE IS
SOME CONCERN WITH THE RESIDUAL UPPER TROUGH THAT DOES NOT WANT TO GO
AWAY. THE MODELS ARE SHOWING THE UPPER TROUGH INITIALLY MOVING TO
THE EAST. THIS WILL BRING SOME DRIER AND COOLER AIR TO THE AREA FOR
A WHILE...BUT THEN THE MODELS SHOW THE REMNANTS OF THE UPPER LOW OVER
OHIO ON SUNDAY. THE LOW THEN MEANDERS SOUTH OVER TIME. WITH ALL THE
SOLUTIONS...ALL THE FRONTS WILL STAY NORTH OF THE AREA AND EASTERN
KENTUCKY WILL JUST BE GENERAL AIR MASS CONVECTIVE ACTIVITY AND WILL
BE FAIRLY WARM AND HUMID. THE CONFIDENCE TENDS TO GO DOWN AFTER
SUNDAY FOR THE REST OF THE PERIOD BECAUSE IT WILL BE SO HARD TO TELL
WHERE THE AREAS OF ORGANIZED CONVECTION WILL BE. IN GENERAL WENT WITH
A MODEL BLEND...HOWEVER DID AN EXTRA NUDGE TOWARD THE ECMWF. FOR
TEMPERATURES...WENT A BIT COOLER THAN THE MODEL BLEND FOR THE SUNDAY
THROUGH WEDNESDAY TIME FRAME STAYING CLOSER TO THE ECMWF RAW OUTPUT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 658 PM EDT WED JUL 10 2013
COLD FRONT CURRENTLY ALONG THE OHIO RIVER WILL SLOWLY PRESS SOUTHEAST
OVER THE NEXT 24 HOURS...CLEARING SOUTHEAST KY THURSDAY AFTERNOON.
NUMEROUS SHOWERS AND THUNDERSTORMS WILL OCCUR AHEAD OF THE COLD
FRONT. LINE OF STRONG STORMS CLEARING THE AREA WITH NUMEROUS SHOWERS
AND LIGHT RAIN EXPECTED TO AFFECT ALL TAF SITES INTO THE OVERNIGHT
PERIOD. AS THE MORE WIDESPREAD PRECIPITATION MOVES IN...EXPECT
CONDITIONS TO DETERIORATE TONIGHT TO MVFR AND IFR. CONDITIONS SHOULD
IMPROVE BACK TO VFR BEFORE 18Z ON THURSDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DUSTY
SHORT TERM...SBH
LONG TERM...JJ
AVIATION...DUSTY
AREA FORECAST DISCUSSION
NWS JACKSON KY
659 PM EDT WED JUL 10 2013
.UPDATE...
ISSUED AT 600 PM EDT WED JUL 10 2013
HAVE HAD ONLY 1 REPORT OF WIND DAMAGE SO FAR...AND SEVERE THREAT IS
DIMINISHING. WILL BE UPDATING NDFD FOR LATEST OBSERVATIONAL TRENDS
AND FOR CURRENT MOVEMENT OF SHOWERS AND THUNDERSTORMS ACROSS THE
FORECAST AREA. PLAN TO BEGIN TRIMMING COUNTIES FROM THE SEVERE
THUNDERSTORM WATCH ON THE WESTERN PART OF THE FORECAST AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 304 PM EDT WED JUL 10 2013
WILL ADD PIKE...LETCHER AND HARLAN COUNTY TO FLASH FLOOD WATCH.
WITH CONVECTION IN THESE AREAS ALREADY OCCURRING TODAY...THEY WILL BE
PRIMED FOR POTENTIAL FLASH FLOODING WITH ADDITIONAL ACTIVITY THIS
EVENING AND OVERNIGHT. COLD FRONT CURRENTLY IN NORTHWEST INDIANA WILL
BE ONLY SLOWLY PRESSING SOUTHEAST OVERNIGHT AND NOT CLEARING
SOUTHEAST KY UNTIL THURSDAY AFTERNOON. LATEST MODEL GUIDANCE AND
ESPECIALLY CURRENT RADAR TRENDS POINTING TOWARDS MULTIPLE ROUNDS OF
SHOWERS AND THUNDERSTORMS FROM LATE THIS AFTERNOON INTO TONIGHT.
PRECIPITABLE WATER AROUND 1.8 THIS AFTERNOON AND WILL NOT SEE MUCH
DECREASE UNTIL AFTER FRONTAL PASSAGE ON THURSDAY...AND THUNDERSTORMS
WILL CONTINUE TO BE CAPABLE OF PRODUCING VERY HEAVY RAIN.
CONSIDERABLE DESTABILIZATION HAS OCCURRED THIS AFTERNOON AND SEVERE
THREAT ALSO INCREASING...WITH SEVERE REPORTS ALREADY OCCURRING IN
CENTRAL KY. HRRR IS POINTING TOWARDS ACTIVITY OVER CENTRAL KY MERGING
INTO A BOWING LINE WHICH WOULD INCREASE SEVERE THREAT OVER SE KY
EARLY THIS EVENING.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 334 PM EDT WED JUL 10 2013
THERE IS DECENT AGREEMENT WITH THE VARIOUS MODELS HOWEVER THERE IS
SOME CONCERN WITH THE RESIDUAL UPPER TROUGH THAT DOES NOT WANT TO GO
AWAY. THE MODELS ARE SHOWING THE UPPER TROUGH INITIALLY MOVING TO
THE EAST. THIS WILL BRING SOME DRIER AND COOLER AIR TO THE AREA FOR
A WHILE...BUT THEN THE MODELS SHOW THE REMNANTS OF THE UPPER LOW OVER
OHIO ON SUNDAY. THE LOW THEN MEANDERS SOUTH OVER TIME. WITH ALL THE
SOLUTIONS...ALL THE FRONTS WILL STAY NORTH OF THE AREA AND EASTERN
KENTUCKY WILL JUST BE GENERAL AIR MASS CONVECTIVE ACTIVITY AND WILL
BE FAIRLY WARM AND HUMID. THE CONFIDENCE TENDS TO GO DOWN AFTER
SUNDAY FOR THE REST OF THE PERIOD BECAUSE IT WILL BE SO HARD TO TELL
WHERE THE AREAS OF ORGANIZED CONVECTION WILL BE. IN GENERAL WENT WITH
A MODEL BLEND...HOWEVER DID AN EXTRA NUDGE TOWARD THE ECMWF. FOR
TEMPERATURES...WENT A BIT COOLER THAN THE MODEL BLEND FOR THE SUNDAY
THROUGH WEDNESDAY TIME FRAME STAYING CLOSER TO THE ECMWF RAW OUTPUT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 658 PM EDT WED JUL 10 2013
COLD FRONT CURRENTLY ALONG THE OHIO RIVER WILL SLOWLY PRESS SOUTHEAST
OVER THE NEXT 24 HOURS...CLEARING SOUTHEAST KY THURSDAY AFTERNOON.
NUMEROUS SHOWERS AND THUNDERSTORMS WILL OCCUR AHEAD OF THE COLD
FRONT. LINE OF STRONG STORMS CLEARING THE AREA WITH NUMEROUS SHOWERS
AND LIGHT RAIN EXPECTED TO AFFECT ALL TAF SITES INTO THE OVERNIGHT
PERIOD. AS THE MORE WIDESPREAD PRECIPITATION MOVES IN...EXPECT
CONDITIONS TO DETERIORATE TONIGHT TO MVFR AND IFR. CONDITIONS SHOULD
IMPROVE BACK TO VFR BEFORE 18Z ON THURSDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 6 AM EDT THURSDAY FOR KYZ044-050>052-
058>060-068-069-079-080-083>088-104-106>120.
&&
$$
UPDATE...SBH
SHORT TERM...SBH
LONG TERM...JJ
AVIATION...DUSTY
AREA FORECAST DISCUSSION
NWS JACKSON KY
329 PM EDT TUE JUL 9 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 329 PM EDT TUE JUL 9 2013
ISOLD TO SCT SHOWERS AND THUNDERSTORMS ARE DEVELOPING ACROSS THE
AREA THIS AFTERNOON. MORE SUBSTANTIAL AREA OF CONVECTION HAS FIRED
OVER OHIO. HRRR HAS ACTUALLY BEEN DOING DECENT WITH CONVECTIVE
INITIATION ACROSS AREAS NORTH OF THE OHIO RIVER. IN GENERAL IT KEEPS
THE BULK OF ACTIVITY NORTH AND EAST OF OUR CWA...THOUGH RADAR TRENDS
WOULD SUGGEST THAT OUR NORTHERN AND EASTERN COUNTIES MAY GET BRUSHED.
INCREASED POPS ACROSS THE NORTHERN/EASTERN PORTIONS OF OUR CWA FOR
THE LATE AFTERNOON AND EARLY EVENING TIME FRAME. PER THE HRRR...WITH
COMPLEX OF STORMS PASSING GENERALLY TO OUR EAST THIS EVENING AND LOSS
OF DIURNAL HEATING GRADUALLY DROPPED POPS OFF THROUGH THE NIGHT.
HOWEVER...RAMPED POPS BACK UP TOWARDS DAWN AS SHORT TERM HIGH
RESOLUTION MODELS SUGGEST THE POSSIBILITY OF THE REMNANTS OF ANOTHER
COMPLEX OF STORMS ENTERING THE AREA FROM THE NORTHWEST.
OTHERWISE...MODELS ARE IN FAIRLY GOOD AGREEMENT THROUGH THE SHORT
TERM. A DEEPENING UPPER LEVEL TROUGH AND REFLECTED SFC COLD FRONT
WILL GRADUALLY PUSH THROUGH THE REGION WEDNESDAY NIGHT INTO EARLY
THURSDAY MORNING. PWATS OVER THE NEXT 36 TO 48 HOURS ARE SIGNIFICANT
HITTING CLIMATOLOGICAL HIGHS AT TIMES. FORECAST SOUNDINGS ARE NOT IN
AS GOOD AGREEMENT WITH RESPECT TO STORM MOTION THOUGH. THE GFS IS
MORE PROGRESSIVE WITH MOVEMENT WHEN COMPARED TO THE HIGHER RESOLUTION
RAP AND NAM. REGARDLESS...WITH SUCH HIGH PWATS AND CONSIDERING A
FAIRLY SATURATED GROUND FEEL THERE WILL BE THE POTENTIAL FOR SOME
LOCALLY HEAVY RAINFALL AND MINOR HYDRO ISSUES...ESPECIALLY WITH THE
STRONGER STORMS. CONFIDENCE WAS LACKING WITH RESPECT TO A WIDESPREAD
THREAT SO OPTED NOT TO ISSUE ANY TYPE OF FFA. BUT MAY RECONSIDER A
FLASH FLOOD WATCH WITH FUTURE FORECAST PACKAGES SHOULD MODELS COME
INTO A LITTLE BETTER AGREEMENT WITH RESPECT TO DETAILS...AND SHOW A
MORE SIGNIFICANT THREAT. FOR NOW WILL CONTINUE TO COVER THIS
POTENTIAL IN THE HWO AND PASS CONCERNS ON TO FUTURE SHIFTS. GENERALLY
FOLLOWED INHERITED TEMPS...NUDGING SLIGHTLY TOWARDS A BLEND OF MODEL
GUIDANCE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 329 PM EDT TUE JUL 9 2013
THE MODELS HAVE A SIMILAR IDEA...THROUGH THE EXTENDED...OF A MID
LEVEL PATTERN DOMINATED BY A LARGE AREA OF RIDGING...INITIALLY OVER
THE SOUTHERN ROCKIES EXPANDING NORTHEAST WITH TIME...AND DOWNSTREAM
TROUGHING THROUGH THE GREAT LAKES LATER AFFECTING MUCH OF THE EAST
AND DEEP SOUTH. THE GREAT LAKES TROUGH STRENGTHENS A BIT ON
THURSDAY AS ITS CORE MOVES EAST AND INTO UPSTATE NEW YORK BY 12Z
FRIDAY. AT THE SAME TIME...ITS TRAILING AXIS AND MAIN ENERGY BAND
WILL SWEEP SOUTHEAST THROUGH THE LOWER OHIO VALLEY AND ACROSS EAST
KENTUCKY. THIS WILL ALLOW HEIGHTS TO BUILD IN FROM THE NORTHWEST
THROUGH THE WEEKEND WHILE THE SOUTHERN PORTION OF THE TROUGH CUTS
OFF OVER THE DEEP SOUTH AND STARTS TO CONSOLIDATE. THOUGH THE MODELS
GENERALLY AGREE ON THE RIDGE PLACEMENT...THEY DIFFER ON THE DETAILS
REGARDING THE LOWER HEIGHT CENTERS TO THE SOUTH AND EAST. INTO THIS
MIX WILL ENTER THE UPPER HEIGHT FIELD OF CHANTAL...OR WHATEVER
BECOMES OF HER...THAT COULD MOVE TO THE SOUTHEAST COAST PER THE GEM
OR STAY LOCKED OUT TO THE SOUTH AS SEEN IN THE GFS AND ECMWF. EITHER
WAY...ITS MOISTURE MAY START TO IMPACT THE AREA AS EARLY AS LATE
SUNDAY...LINGERING THROUGH THE REST OF THE EXTENDED. FOR EAST
KENTUCKY...THE RIDGE TO THE NORTH WILL BE A KEY COMPONENT IN
DETERMINING OUR WEATHER INTO THE START OF NEXT WEEK. WITH THE MODELS
IN BETTER AGREEMENT ON THIS FEATURE CONFIDENCE IS HIGHER IN GOING
DRY THROUGH AT LEAST MIDDAY SUNDAY. THEREAFTER...THE GFS...AND TO A
LESSER EXTENT THE ECMWF...DOES BRING AN UPPER LOW WEST TOWARD THE
AREA FOR TUESDAY. WITH THE DECENT AGREEMENT AMONG THE MODELS ON THE
RIDGE THROUGH THE WEEKEND...EXPECT THAT A BLEND WILL BE AN EFFECTIVE
STARTING POINT THROUGH SUNDAY. AFTER THAT...WILL LEAN MORE TOWARD
THE WEAKER...LESS AMPLIFIED...00Z ECMWF.
SENSIBLE WEATHER WILL LIKELY FEATURE SOME ONGOING CONVECTION MOVING
SOUTHEAST THROUGH THIS PART OF THE STATE ON THURSDAY MORNING AS A
COLD FRONT PASSES THROUGH EARLY IN THE DAY. HIGH PRESSURE WILL THEN
BUILD IN AND BRING A RARE SUMMER TIME SHOT OF COOLER AND DRIER AIR
FROM THE NORTH. THIS SFC HIGH...AND THE DRY WEATHER...WILL BE
SUSTAINED BY THE RIDGING BUILDING ALOFT AND SHOULD SERVE TO KEEP ANY
TROPICAL DERIVED MOISTURE OFF TO THE SOUTH AND EAST FOR THE BULK OF
THE WEEKEND. HOWEVER...THE RIDGE ALOFT WILL WEAKEN AND MOVE BACK
WEST BY LATE SUNDAY WHILE THE CORRESPONDING SFC HIGH WILL ALSO BREAK
DOWN AND ALLOW HIGH DEWPOINTS INTO THE REGION FROM THE SOUTHEAST. A
DIURNAL REGIME SHOULD THEN GUIDE THE CONVECTIVE DEVELOPMENTS ON
MONDAY AND TUESDAY WITH BUILDING INSTABILITY AND LITTLE IN THE WAY
OF CAPPING LEADING TO SCATTERED SHOWERS AND THUNDERSTORMS EACH
AFTERNOON...PARTICULARLY ACROSS OUR SOUTHEAST COUNTIES.
THE CR GRID LOAD CAME IN REASONABLE...THOUGH DID ADJUST POPS A BIT
ON SUNDAY AND MONDAY NIGHTS TO BETTER EMPHASIZE THE DIURNAL NATURE
OF THE CONVECTION. ALSO...TWEAKED OVERNIGHT LOWS ON THURSDAY THROUGH
SATURDAY NIGHTS TO ACCOUNT FOR TERRAIN BASED DIFFERENCES IN
RADIATIONAL COOLING WHILE WE ARE BENEFITING FROM THE DRIER AIR MASS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 215 PM EDT TUE JUL 9 2013
EXTENSIVE CUMULUS FIELD WILL BE IN PLACE THROUGH THE REMAINDER OF THE
AFTERNOON WITH GENERALLY SCT SKY CONDITIONS AND CLOUD BASES FROM 3000
TO 5000 FEET. WENT WITH VFR CONDITIONS THROUGH THE ENTIRE FORECAST
PERIOD. HOWEVER...STILL HAVE TO DEAL WITH CONVECTION THIS AFTERNOON
AND INTO TONIGHT. DIURNAL HEATING AND INSTABILITY IS HELPING TO KICK
OFF SOME SHOWERS ACROSS THE AREA AT TAF ISSUANCE. ASSESSING THE
DIRECT IMPACTS OF SHOWERS AND THUNDERSTORMS AT EACH TERMINAL IS AT
BEST DIFFICULT...ESPECIALLY SINCE CELLS APPEAR TO HAVE A RELATIVELY
SHORT LIFE CYCLE...BUILDING AND THEN DISSIPATING WITHIN AN HOUR.
MORE ORGANIZED CONVECTION MAY DROP SOUTHWARD INTO PORTIONS OF THE
AREA LATER THIS EVENING. CLOSELY WATCHING THE DEVELOPMENT AND
EVOLUTION OF UPSTREAM ACTIVITY. JKL WOULD BE MOST LIKELY TO BE
EFFECTED BY ANYTHING. PRECIP POTENTIAL...LATE AFTERNOON AND EARLY
EVENING RAINFALL WOULD BOOST POTENTIAL FOR BR/FOG DEVELOPMENT
OVERNIGHT. BUT FOR NOW WENT MORE OPTIMISTIC THAN MODEL GUIDANCE WITH
ONLY SOME LIGHT MIST. WINDS WILL RELATIVELY LIGHT THROUGH THE
PERIOD...AND GENERALLY FROM THE SOUTHWEST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...RAY
LONG TERM...GREIF
AVIATION...JMW/RAY
AREA FORECAST DISCUSSION
NWS GRAY ME
947 PM EDT WED JUL 10 2013
.SYNOPSIS...
A WARM FRONT WILL PUSH NORTHEAST ACROSS THE REGION EARLY TONIGHT
WITH A COLD FRONT PUSHING EAST ACROSS THE REGION LATE TONIGHT.
THE COLD FRONT WILL STALL JUST OFF THE COAST THURSDAY AND THURSDAY
NIGHT. LOW PRESSURE WILL TRACK JUST OFFSHORE ALONG THE STALLED
FRONT LATE FRIDAY AND FRIDAY NIGHT. THE FRONT WILL WASHOUT OVER
THE WEEKEND AS HIGH PRESSURE ANCHORED OFFSHORE BUILDS WESTWARD
INTO THE REGION.
&&
.NEAR TERM /THROUGH THURSDAY/...
UPDATE...
THIS LATEST UPDATE WAS TO ISSUE A DENSE FOG ADVISORY FOR SOUTHERN
AREAS. MANY LOCATIONS HAVE DROPPED TO A QUARTER MILE OR LESS VSBY
THIS EVENING AS DEW POINTS CONTINUE TO SLOWLY RISE.
PREV DISC...
HAVE UPDATED THE GRIDS TO ADD FOG FOR PORTIONS OF THE
COASTLINE AND THE COASTAL WATERS. VSBY NOW DOWN TO 1/8 MILE IN
PORTLAND. HAVE ALSO ADDED HEAVY RAINFALL TO THE FORECASTS AS A
QUICK ONE TO TWO INCHES OF RAIN WILL ACCUMULATE IN MANY AREAS.
LATEST HRRR RUN DECREASES MOST OF THE PCPN BY AROUND 02Z OVER
CENTRAL MAINE.
SHOWERS AND THUNDERSTORMS WILL CONTINUE TO SPREAD NORTHEAST. WARM
FRONT IS SITUATED OVER SE NH...SO SOME OF THIS CONVECTION WILL BE
WEAKENING AS IT ENTERS MAINE. SO FAR...NO HYDRO PROBLEMS AS THE
PCPN IS MOVING QUICKLY ENOUGH.
PREV DISC...
THE WARM FRONT WILL PUSH NORTHEAST ACROSS THE FORECAST AREA
EARLY TONIGHT WITH A COLD FRONT MOVING IN FROM THE WEST. THE COLD
FRONT WILL MOVE THROUGH LATE TONIGHT. THESE SYSTEMS WILL PROVIDE
CLOUDS AND FOG OVERNIGHT. SHOWERS AND A FEW THUNDERSTORMS, SOME
WITH HEAVY RAIN, ALREADY ON RADAR POISED TO MOVE INTO NEW
HAMPSHIRE THIS AFTERNOON WILL CONTINUE TO MOVE EAST ACROSS THE
FORECAST AREA. HOWEVER... AS THIS CONVECTION MOVES EASTWARD INTO
THE STABLE MARINE AIR OVER MAINE AND PORTIONS OF EASTERN NEW
HAMPSHIRE THE INTENSITY OF THE CONVECTION WILL WEAKEN CONSIDERABLY
SUCH THAT THUNDER AND HEAVY RAIN WILL LIKELY NOT OCCUR OVER MAINE.
HUMID CONDITIONS WILL CONTINUE AS TEMPERATURES DON`T DROP MUCH
OVERNIGHT WITH DEW POINTS IN THE 60S OVER MAINE AND AROUND 70 OVER
A GOOD PART OF NEW HAMPSHIRE. EXPECT OVERNIGHT LOWS IN THE 60S
MOST EVERYWHERE. USED A BLEND OF MAV/MET MOS GUIDANCE FOR
OVERNIGHT LOWS.
QPF AMOUNTS BASED ON RFC THOUGH DID INCREASE SOME OVERNIGHT OVER
SOUTHERN AREAS. MAX QPF THIS AFTERNOON THROUGH TONIGHT OVER OUR
SOUTHERN NEW HAMPSHIRE ZONES WHERE THREE QUARTERS OF AN INCH IS
LIKELY...THOUGH HEAVIER AMOUNTS ARE POSSIBLE WITH ANY
THUNDERSTORMS. THIS AREA THAT WILL LIKELY SEE THE MOST RAINFALL
HAS THE POTENTIAL FOR FLASH FLOODING IF HEAVY RAIN FALLS OVER A
SHORT PERIOD OF TIME. WILL CONTINUE THE FLASH FLOOD WATCH FOR
WESTERN AND SOUTHERN NEW HAMPSHIRE ZONES THROUGH 10 PM THIS
EVENING.
&&
.SHORT TERM /THURSDAY NIGHT/...
THE COLD FRONT STALLS JUST OFFSHORE UNDER AN UPPER LEVEL
SOUTHWEST FLOW AHEAD OF A SLOWLY APPROACHING UPPER LEVEL TROUGH.
THIS STALLED FRONT KEEPS MOISTURE IN OVER OUR SOUTHEAST ZONES
WHILE SOME DRIER AIR MOVES INTO NORTHWEST ZONES AS HIGH PRESSURE
APPROACHES FROM CANADA AND THE GREAT LAKES REGION THURSDAY AND
THURSDAY NIGHT.
LOOKING FOR MORE CLOUDS AND A BETTER CHANCE OF SHOWERS ALONG THE
COAST AND INTO ADJACENT INTERIOR ZONES WHILE THE NORTH AND
MOUNTAIN AREAS HAVE THE LOWEST CHANCE OF RAIN AND THE LEAST AMOUNT
OF CLOUDINESS. QPF BASED ON RFC GUIDANCE AND SHOULD BE MOSTLY ON
THE LIGHT SIDE...THOUGH SOUTHEAST NEW HAMPSHIRE INTO COASTAL MAINE
COULD SEE A 24 HOUR TOTAL THURSDAY AND THURSDAY NIGHT AROUND A
THIRD OF AN INCH. USED A BLEND OF MAV/MET MOS GUIDANCE FOR
TEMPERATURES WHICH WARM INTO THE MID 70S TO LOWER 80S THURSDAY AND
COOL INTO THE 50S OVER THE NORTH AND MOUNTAINS WHILE ONLY DROPPING
INTO THE LOWER AND MIDDLE 60S ELSEWHERE.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
THE LATEST AVAILABLE MODEL SUITE HAS THE UPPER TROUGH WEAKENING
ACROSS NEW ENGLAND THIS WEEKEND BEFORE RETROGRADING TO THE SOUTH
AND WEST ALLOWING THE UPPER RIDGE TO BUILD ACROSS THE REGION. SOME
SIGNS THAT THE RIDGE WEAKENS TOWARDS THE END OF THE PERIOD
ALLOWING A TRAILING COLD FRONT TO CROSS THE AREA WITH THE
PROSPECTS FOR MORE WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY. OF
MORE IMMEDIATE CONCERN IS THE COLD FRONT POISED TO STALL JUST OFF
THE COAST EARLY IN THE PERIOD. THE MODELS SUGGEST THAT A WAVE
RIDING NORTHEAST ALONG THE BOUNDARY WILL BRING SHOWERS...AND
PERHAPS A PERIOD OF STEADIER RAIN TO COASTAL SECTIONS LATE FRIDAY
INTO SATURDAY. OTHERWISE...SEVERAL DAYS OF HOT HUMID WEATHER WITH
SCATTERED SHOWERS AND THUNDERSTORMS EXPECTED. BOTH TEMPERATURES
AND PRECIPITATION ARE LIKELY TO AVERAGE ABOVE NORMAL FOR THE
PERIOD.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
SHORT TERM /THROUGH THURSDAY NIGHT/...CONDITIONS LOWER TO LIFR
OR AT LEAST DOWN TO IFR MOST AREAS TONIGHT IN LOW CLOUDS AND FOG
WITH SOME SHOWERS AROUND THROUGH EARLY TONIGHT. POSSIBLE
THUNDERSTORMS MAINLY OVER NEW HAMPSHIRE THROUGH THIS EVENING BUT
PROBABILITY NOT HIGH ENOUGH TO INCLUDE IN THE TAFS AT THIS TIME.
CONDITIONS IMPROVE ON THURSDAY TO MVFR AND MAYBE VFR WELL INLAND
IN THE AFTERNOON. VFR TO MVFR THURSDAY NIGHT WITH POSSIBLE IFR
NEAR THE COAST WHERE THERE IS A BETTER CHANCE OF SHOWERS FROM AN
OFFSHORE FRONTAL SYSTEM.
LONG TERM...
FRI NIGHT - SAT...AREAS OF MVFR VCNTY OF THE COAST IN SHOWERS AND TSTMS.
SUN - MON...SCT MVFR POSSIBLE IN SHOWERS AND TSTMS.
&&
.MARINE...
SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...CONDITIONS STAY
BELOW SMALL CRAFT ADVISORY LEVELS THROUGH THE SHORT TERM. AHEAD OF
AN APPROACHING COLD FRONT TONIGHT... WINDS BACK TO THE SOUTHWEST
AND INCREASE TONIGHT WITH SOME GUSTS AROUND 20 KNOTS POSSIBLE.
SEAS BUILD AS WELL...TO AS HIGH AS 4 FEET OVER THE OUTER WATERS.
WINDS AND SEAS DROP OFF AS THE FRONT SETTLES OVER THE WATERS
THURSDAY AND THURSDAY NIGHT.
LONG TERM...
SAT...WINDS AND SEAS MAY APPROACH SCA THRESHOLD OUTSIDE THE BAYS.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...DENSE FOG ADVISORY UNTIL 6 AM EDT THURSDAY FOR MEZ020>028.
NH...NONE.
MARINE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAY ME
745 PM EDT WED JUL 10 2013
.SYNOPSIS...
A WARM FRONT WILL PUSH NORTHEAST ACROSS THE REGION EARLY TONIGHT
WITH A COLD FRONT PUSHING EAST ACROSS THE REGION LATE TONIGHT.
THE COLD FRONT WILL STALL JUST OFF THE COAST THURSDAY AND THURSDAY
NIGHT. LOW PRESSURE WILL TRACK JUST OFFSHORE ALONG THE STALLED
FRONT LATE FRIDAY AND FRIDAY NIGHT. THE FRONT WILL WASHOUT OVER
THE WEEKEND AS HIGH PRESSURE ANCHORED OFFSHORE BUILDS WESTWARD
INTO THE REGION.
&&
.NEAR TERM /THROUGH THURSDAY/...
UPDATE...
THIS LATEST UPDATE WAS TO ISSUE A DENSE FOG ADVISORY FOR SOUTHERN
AREAS. MANY LOCATIONS HAVE DROPPED TO A QUARTER MILE OR LESS VSBY
THIS EVENING AS DEW POINTS CONTINUE TO SLOWLY RISE.
PREV DISC...
HAVE UPDATED THE GRIDS TO ADD FOG FOR PORTIONS OF THE
COASTLINE AND THE COASTAL WATERS. VSBY NOW DOWN TO 1/8 MILE IN
PORTLAND. HAVE ALSO ADDED HEAVY RAINFALL TO THE FORECASTS AS A
QUICK ONE TO TWO INCHES OF RAIN WILL ACCUMULATE IN MANY AREAS.
LATEST HRRR RUN DECREASES MOST OF THE PCPN BY AROUND 02Z OVER
CENTRAL MAINE.
SHOWERS AND THUNDERSTORMS WILL CONTINUE TO SPREAD NORTHEAST. WARM
FRONT IS SITUATED OVER SE NH...SO SOME OF THIS CONVECTION WILL BE
WEAKENING AS IT ENTERS MAINE. SO FAR...NO HYDRO PROBLEMS AS THE
PCPN IS MOVING QUICKLY ENOUGH.
PREV DISC...
THE WARM FRONT WILL PUSH NORTHEAST ACROSS THE FORECAST AREA
EARLY TONIGHT WITH A COLD FRONT MOVING IN FROM THE WEST. THE COLD
FRONT WILL MOVE THROUGH LATE TONIGHT. THESE SYSTEMS WILL PROVIDE
CLOUDS AND FOG OVERNIGHT. SHOWERS AND A FEW THUNDERSTORMS, SOME
WITH HEAVY RAIN, ALREADY ON RADAR POISED TO MOVE INTO NEW
HAMPSHIRE THIS AFTERNOON WILL CONTINUE TO MOVE EAST ACROSS THE
FORECAST AREA. HOWEVER... AS THIS CONVECTION MOVES EASTWARD INTO
THE STABLE MARINE AIR OVER MAINE AND PORTIONS OF EASTERN NEW
HAMPSHIRE THE INTENSITY OF THE CONVECTION WILL WEAKEN CONSIDERABLY
SUCH THAT THUNDER AND HEAVY RAIN WILL LIKELY NOT OCCUR OVER MAINE.
HUMID CONDITIONS WILL CONTINUE AS TEMPERATURES DON`T DROP MUCH
OVERNIGHT WITH DEW POINTS IN THE 60S OVER MAINE AND AROUND 70 OVER
A GOOD PART OF NEW HAMPSHIRE. EXPECT OVERNIGHT LOWS IN THE 60S
MOST EVERYWHERE. USED A BLEND OF MAV/MET MOS GUIDANCE FOR
OVERNIGHT LOWS.
QPF AMOUNTS BASED ON RFC THOUGH DID INCREASE SOME OVERNIGHT OVER
SOUTHERN AREAS. MAX QPF THIS AFTERNOON THROUGH TONIGHT OVER OUR
SOUTHERN NEW HAMPSHIRE ZONES WHERE THREE QUARTERS OF AN INCH IS
LIKELY...THOUGH HEAVIER AMOUNTS ARE POSSIBLE WITH ANY
THUNDERSTORMS. THIS AREA THAT WILL LIKELY SEE THE MOST RAINFALL
HAS THE POTENTIAL FOR FLASH FLOODING IF HEAVY RAIN FALLS OVER A
SHORT PERIOD OF TIME. WILL CONTINUE THE FLASH FLOOD WATCH FOR
WESTERN AND SOUTHERN NEW HAMPSHIRE ZONES THROUGH 10 PM THIS
EVENING.
&&
.SHORT TERM /THURSDAY NIGHT/...
THE COLD FRONT STALLS JUST OFFSHORE UNDER AN UPPER LEVEL
SOUTHWEST FLOW AHEAD OF A SLOWLY APPROACHING UPPER LEVEL TROUGH.
THIS STALLED FRONT KEEPS MOISTURE IN OVER OUR SOUTHEAST ZONES
WHILE SOME DRIER AIR MOVES INTO NORTHWEST ZONES AS HIGH PRESSURE
APPROACHES FROM CANADA AND THE GREAT LAKES REGION THURSDAY AND
THURSDAY NIGHT.
LOOKING FOR MORE CLOUDS AND A BETTER CHANCE OF SHOWERS ALONG THE
COAST AND INTO ADJACENT INTERIOR ZONES WHILE THE NORTH AND
MOUNTAIN AREAS HAVE THE LOWEST CHANCE OF RAIN AND THE LEAST AMOUNT
OF CLOUDINESS. QPF BASED ON RFC GUIDANCE AND SHOULD BE MOSTLY ON
THE LIGHT SIDE...THOUGH SOUTHEAST NEW HAMPSHIRE INTO COASTAL MAINE
COULD SEE A 24 HOUR TOTAL THURSDAY AND THURSDAY NIGHT AROUND A
THIRD OF AN INCH. USED A BLEND OF MAV/MET MOS GUIDANCE FOR
TEMPERATURES WHICH WARM INTO THE MID 70S TO LOWER 80S THURSDAY AND
COOL INTO THE 50S OVER THE NORTH AND MOUNTAINS WHILE ONLY DROPPING
INTO THE LOWER AND MIDDLE 60S ELSEWHERE.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
THE LATEST AVAILABLE MODEL SUITE HAS THE UPPER TROUGH WEAKENING
ACROSS NEW ENGLAND THIS WEEKEND BEFORE RETROGRADING TO THE SOUTH
AND WEST ALLOWING THE UPPER RIDGE TO BUILD ACROSS THE REGION. SOME
SIGNS THAT THE RIDGE WEAKENS TOWARDS THE END OF THE PERIOD
ALLOWING A TRAILING COLD FRONT TO CROSS THE AREA WITH THE
PROSPECTS FOR MORE WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY. OF
MORE IMMEDIATE CONCERN IS THE COLD FRONT POISED TO STALL JUST OFF
THE COAST EARLY IN THE PERIOD. THE MODELS SUGGEST THAT A WAVE
RIDING NORTHEAST ALONG THE BOUNDARY WILL BRING SHOWERS...AND
PERHAPS A PERIOD OF STEADIER RAIN TO COASTAL SECTIONS LATE FRIDAY
INTO SATURDAY. OTHERWISE...SEVERAL DAYS OF HOT HUMID WEATHER WITH
SCATTERED SHOWERS AND THUNDERSTORMS EXPECTED. BOTH TEMPERATURES
AND PRECIPITATION ARE LIKELY TO AVERAGE ABOVE NORMAL FOR THE
PERIOD.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
SHORT TERM /THROUGH THURSDAY NIGHT/...CONDITIONS LOWER TO LIFR
OR AT LEAST DOWN TO IFR MOST AREAS TONIGHT IN LOW CLOUDS AND FOG
WITH SOME SHOWERS AROUND THROUGH EARLY TONIGHT. POSSIBLE
THUNDERSTORMS MAINLY OVER NEW HAMPSHIRE THROUGH THIS EVENING BUT
PROBABILITY NOT HIGH ENOUGH TO INCLUDE IN THE TAFS AT THIS TIME.
CONDITIONS IMPROVE ON THURSDAY TO MVFR AND MAYBE VFR WELL INLAND
IN THE AFTERNOON. VFR TO MVFR THURSDAY NIGHT WITH POSSIBLE IFR
NEAR THE COAST WHERE THERE IS A BETTER CHANCE OF SHOWERS FROM AN
OFFSHORE FRONTAL SYSTEM.
LONG TERM...
FRI NIGHT - SAT...AREAS OF MVFR VCNTY OF THE COAST IN SHOWERS AND TSTMS.
SUN - MON...SCT MVFR POSSIBLE IN SHOWERS AND TSTMS.
&&
.MARINE...
SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...CONDITIONS STAY
BELOW SMALL CRAFT ADVISORY LEVELS THROUGH THE SHORT TERM. AHEAD OF
AN APPROACHING COLD FRONT TONIGHT... WINDS BACK TO THE SOUTHWEST
AND INCREASE TONIGHT WITH SOME GUSTS AROUND 20 KNOTS POSSIBLE.
SEAS BUILD AS WELL...TO AS HIGH AS 4 FEET OVER THE OUTER WATERS.
WINDS AND SEAS DROP OFF AS THE FRONT SETTLES OVER THE WATERS
THURSDAY AND THURSDAY NIGHT.
LONG TERM...
SAT...WINDS AND SEAS MAY APPROACH SCA THRESHOLD OUTSIDE THE BAYS.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...DENSE FOG ADVISORY UNTIL 6 AM EDT THURSDAY FOR MEZ020>028.
NH...NONE.
MARINE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAY ME
719 PM EDT WED JUL 10 2013
.SYNOPSIS...
A WARM FRONT WILL PUSH NORTHEAST ACROSS THE REGION EARLY TONIGHT
WITH A COLD FRONT PUSHING EAST ACROSS THE REGION LATE TONIGHT.
THE COLD FRONT WILL STALL JUST OFF THE COAST THURSDAY AND THURSDAY
NIGHT. LOW PRESSURE WILL TRACK JUST OFFSHORE ALONG THE STALLED
FRONT LATE FRIDAY AND FRIDAY NIGHT. THE FRONT WILL WASHOUT OVER
THE WEEKEND AS HIGH PRESSURE ANCHORED OFFSHORE BUILDS WESTWARD
INTO THE REGION.
&&
.NEAR TERM /THROUGH THURSDAY/...
UPDATE...
THIS LATEST UPDATE WAS TO ISSUE A DENSE FOG ADVISORY FOR SOUTHERN
AREAS. MANY LOCATIONS HAVE DROPPED TO A QUARTER MILE OR LESS VSBY
THIS EVENING AS DEW POINTS CONTINUE TO SLOWLY RISE.
PREV DISC...
HAVE UPDATED THE GRIDS TO ADD FOG FOR PORTIONS OF THE
COASTLINE AND THE COASTAL WATERS. VSBY NOW DOWN TO 1/8 MILE IN
PORTLAND. HAVE ALSO ADDED HEAVY RAINFALL TO THE FORECASTS AS A
QUICK ONE TO TWO INCHES OF RAIN WILL ACCUMULATE IN MANY AREAS.
LATEST HRRR RUN DECREASES MOST OF THE PCPN BY AROUND 02Z OVER
CENTRAL MAINE.
SHOWERS AND THUNDERSTORMS WILL CONTINUE TO SPREAD NORTHEAST. WARM
FRONT IS SITUATED OVER SE NH...SO SOME OF THIS CONVECTION WILL BE
WEAKENING AS IT ENTERS MAINE. SO FAR...NO HYDRO PROBLEMS AS THE
PCPN IS MOVING QUICKLY ENOUGH.
PREV DISC...
THE WARM FRONT WILL PUSH NORTHEAST ACROSS THE FORECAST AREA
EARLY TONIGHT WITH A COLD FRONT MOVING IN FROM THE WEST. THE COLD
FRONT WILL MOVE THROUGH LATE TONIGHT. THESE SYSTEMS WILL PROVIDE
CLOUDS AND FOG OVERNIGHT. SHOWERS AND A FEW THUNDERSTORMS, SOME
WITH HEAVY RAIN, ALREADY ON RADAR POISED TO MOVE INTO NEW
HAMPSHIRE THIS AFTERNOON WILL CONTINUE TO MOVE EAST ACROSS THE
FORECAST AREA. HOWEVER... AS THIS CONVECTION MOVES EASTWARD INTO
THE STABLE MARINE AIR OVER MAINE AND PORTIONS OF EASTERN NEW
HAMPSHIRE THE INTENSITY OF THE CONVECTION WILL WEAKEN CONSIDERABLY
SUCH THAT THUNDER AND HEAVY RAIN WILL LIKELY NOT OCCUR OVER MAINE.
HUMID CONDITIONS WILL CONTINUE AS TEMPERATURES DON`T DROP MUCH
OVERNIGHT WITH DEW POINTS IN THE 60S OVER MAINE AND AROUND 70 OVER
A GOOD PART OF NEW HAMPSHIRE. EXPECT OVERNIGHT LOWS IN THE 60S
MOST EVERYWHERE. USED A BLEND OF MAV/MET MOS GUIDANCE FOR
OVERNIGHT LOWS.
QPF AMOUNTS BASED ON RFC THOUGH DID INCREASE SOME OVERNIGHT OVER
SOUTHERN AREAS. MAX QPF THIS AFTERNOON THROUGH TONIGHT OVER OUR
SOUTHERN NEW HAMPSHIRE ZONES WHERE THREE QUARTERS OF AN INCH IS
LIKELY...THOUGH HEAVIER AMOUNTS ARE POSSIBLE WITH ANY
THUNDERSTORMS. THIS AREA THAT WILL LIKELY SEE THE MOST RAINFALL
HAS THE POTENTIAL FOR FLASH FLOODING IF HEAVY RAIN FALLS OVER A
SHORT PERIOD OF TIME. WILL CONTINUE THE FLASH FLOOD WATCH FOR
WESTERN AND SOUTHERN NEW HAMPSHIRE ZONES THROUGH 10 PM THIS
EVENING.
&&
.SHORT TERM /THURSDAY NIGHT/...
THE COLD FRONT STALLS JUST OFFSHORE UNDER AN UPPER LEVEL
SOUTHWEST FLOW AHEAD OF A SLOWLY APPROACHING UPPER LEVEL TROUGH.
THIS STALLED FRONT KEEPS MOISTURE IN OVER OUR SOUTHEAST ZONES
WHILE SOME DRIER AIR MOVES INTO NORTHWEST ZONES AS HIGH PRESSURE
APPROACHES FROM CANADA AND THE GREAT LAKES REGION THURSDAY AND
THURSDAY NIGHT.
LOOKING FOR MORE CLOUDS AND A BETTER CHANCE OF SHOWERS ALONG THE
COAST AND INTO ADJACENT INTERIOR ZONES WHILE THE NORTH AND
MOUNTAIN AREAS HAVE THE LOWEST CHANCE OF RAIN AND THE LEAST AMOUNT
OF CLOUDINESS. QPF BASED ON RFC GUIDANCE AND SHOULD BE MOSTLY ON
THE LIGHT SIDE...THOUGH SOUTHEAST NEW HAMPSHIRE INTO COASTAL MAINE
COULD SEE A 24 HOUR TOTAL THURSDAY AND THURSDAY NIGHT AROUND A
THIRD OF AN INCH. USED A BLEND OF MAV/MET MOS GUIDANCE FOR
TEMPERATURES WHICH WARM INTO THE MID 70S TO LOWER 80S THURSDAY AND
COOL INTO THE 50S OVER THE NORTH AND MOUNTAINS WHILE ONLY DROPPING
INTO THE LOWER AND MIDDLE 60S ELSEWHERE.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
THE LATEST AVAILABLE MODEL SUITE HAS THE UPPER TROUGH WEAKENING
ACROSS NEW ENGLAND THIS WEEKEND BEFORE RETROGRADING TO THE SOUTH
AND WEST ALLOWING THE UPPER RIDGE TO BUILD ACROSS THE REGION. SOME
SIGNS THAT THE RIDGE WEAKENS TOWARDS THE END OF THE PERIOD
ALLOWING A TRAILING COLD FRONT TO CROSS THE AREA WITH THE
PROSPECTS FOR MORE WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY. OF
MORE IMMEDIATE CONCERN IS THE COLD FRONT POISED TO STALL JUST OFF
THE COAST EARLY IN THE PERIOD. THE MODELS SUGGEST THAT A WAVE
RIDING NORTHEAST ALONG THE BOUNDARY WILL BRING SHOWERS...AND
PERHAPS A PERIOD OF STEADIER RAIN TO COASTAL SECTIONS LATE FRIDAY
INTO SATURDAY. OTHERWISE...SEVERAL DAYS OF HOT HUMID WEATHER WITH
SCATTERED SHOWERS AND THUNDERSTORMS EXPECTED. BOTH TEMPERATURES
AND PRECIPITATION ARE LIKELY TO AVERAGE ABOVE NORMAL FOR THE
PERIOD.
&&
.AVIATION /23Z WEDNESDAY THROUGH MONDAY/...
SHORT TERM /THROUGH THURSDAY NIGHT/...CONDITIONS LOWER TO LIFR
OR AT LEAST DOWN TO IFR MOST AREAS TONIGHT IN LOW CLOUDS AND FOG
WITH SOME SHOWERS AROUND THROUGH EARLY TONIGHT. POSSIBLE
THUNDERSTORMS MAINLY OVER NEW HAMPSHIRE THROUGH THIS EVENING BUT
PROBABILITY NOT HIGH ENOUGH TO INCLUDE IN THE TAFS AT THIS TIME.
CONDITIONS IMPROVE ON THURSDAY TO MVFR AND MAYBE VFR WELL INLAND
IN THE AFTERNOON. VFR TO MVFR THURSDAY NIGHT WITH POSSIBLE IFR
NEAR THE COAST WHERE THERE IS A BETTER CHANCE OF SHOWERS FROM AN
OFFSHORE FRONTAL SYSTEM.
LONG TERM...
FRI NIGHT - SAT...AREAS OF MVFR VCNTY OF THE COAST IN SHOWERS AND TSTMS.
SUN - MON...SCT MVFR POSSIBLE IN SHOWERS AND TSTMS.
&&
.MARINE...
SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...CONDITIONS STAY
BELOW SMALL CRAFT ADVISORY LEVELS THROUGH THE SHORT TERM. AHEAD OF
AN APPROACHING COLD FRONT TONIGHT... WINDS BACK TO THE SOUTHWEST
AND INCREASE TONIGHT WITH SOME GUSTS AROUND 20 KNOTS POSSIBLE.
SEAS BUILD AS WELL...TO AS HIGH AS 4 FEET OVER THE OUTER WATERS.
WINDS AND SEAS DROP OFF AS THE FRONT SETTLES OVER THE WATERS
THURSDAY AND THURSDAY NIGHT.
LONG TERM...
SAT...WINDS AND SEAS MAY APPROACH SCA THRESHOLD OUTSIDE THE BAYS.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...DENSE FOG ADVISORY UNTIL 11 PM EDT THIS EVENING FOR MEZ020>028.
NH...FLASH FLOOD WATCH UNTIL 10 PM EDT THIS EVENING FOR NHZ003-005-
007>010-013-014.
MARINE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
519 PM EDT TUE JUL 9 2013
.SYNOPSIS...
A SERIES OF UPPER DISTURBANCES WILL MAINTAIN CHANCES FOR SHOWERS
AND THUNDERSTORMS THROUGH WEDNESDAY. A COLD FRONT WILL MOVE
THROUGH EARLY THURSDAY...BRINGING COOLER AND MORE COMFORTABLE
CONDITIONS FOR THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
AS PREDICTED STORMS ARE FIRING UP ACROSS CENTRAL OHIO AND MOVING
SOUTHEAST INTO EAST CENTRAL OHIO. ATMOSPHERE HAS TONS OF ENERGY TO
WORK WITH AS ANALYZED BY RAP MODEL. MUCAPES EXCEED 3.0 KJKG-1
WHILE MOISTURE CONV AND EQUIV POT TEMP ADV ARE HIGH SUPPORTING
UPSTREAM DEVELOPMENT. BUFR SOUNDINGS SHOW A TROPICAL STATE TO OUR
ENVIRONMENT WITH WARM CLOUD PROCESSES IN EFFECT. UPDATED FORECAST
TO INCREASE POPS OVER E CENTRAL OHIO AND ADD HEAVY RAIN ATTRIBUTE
TO WEATHER GRIDS BASED ON OBSERVED RAINFALL AMOUNTS.
LATEST HRRR CONTINUES TO POINTS TO AN MCS TRAVERSING SERN OH AND
NRN WV DURING THE OVERNIGHT HOURS. THESE ARE LOCATIONS THAT CAN
NOT HANDLE A LOT OF QPF. RAIN AMOUNTS LESS THAN AN INCH PER HOUR
WOULD BE ENOUGH TO CREATE FLASH FLOODING. OUR CURRENT FLASH FLOOD
WATCH LOOKS GOOD WITH NO CHANGES PLANNED. WITH INCREASED
CONFIDENCE PER RECENT HIGH RESOLUTION MODELS...RAISED POP NUMBERS
OVER THE AFOREMENTIONED AREA DURING THE NIGHT TIME HOURS.
TEMPERATURES WERE LEFT CLOSE TO A BLEND OF GFS LAMP/NAM GUIDANCE
TONIGHT.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/...
PCPN ONGOING WED MRNG SHOULD DECR IN CVRG BY MID-MRNG. MDT INSTBY
XPCD TO BCM ESTABLISHED THRU FCST AREA BY LATE MRNG OWING TO
COOLING MID-LVL TEMPS AND ABUNDANT LOW-LVL MSTR CHARACTERIZED BY
DEWPTS IN THE LWR 70S.
MRNG CLD CVR XPCD TO BCM BKN AND ALLOW PATCHY HEATING OF THIS VERY
MOIST AMS...WHICH WILL AID IN BOTH WEAKENING THE CAP AND
STEEPENING LOW-LVL LAPSE RATES. TSTM CVRG XPCD TO INCR MARKEDLY BY
EARLY AFTN. DESPITE WEAK MID-LVL FLOW...MDT INSTBY MAY BE
SUFFICIENT TO SUPPORT TSTM ORGANIZATION. GIVEN XPCD DRY AIR ATOP
DP MOIST LYR...LRG HAIL AND DMGG WIND GUSTS BOTH WILL BE PSBL FROM
ANY TSTMS.
MRNG CLD CVR WILL RESTRICT HEATING INITIALLY. BUT OVNGT MINIMA IN
THE 70S WILL OFFER A HEAD START TO MAXIMA IN THE LWR 80S-MID 80S
FOR TMW.
PWATS WILL RMN QUITE HIGH THRU WED NGT...PSBLY APRCHG 2.0 IN. SUCH
VALUES ARE MORE THAN 2 STANDARD DEVIATIONS ABV NRML VALUES AND
WILL ENCOURAGE VERY HIGH PCPN RATES IN TSTMS. FLASH FLOOD WATCH
CONTS THRU WED NGT DURG THIS PD OF HIGH PWATS.
CDFNT WILL PROGRESS THRU FCST AREA WED NGT...LKLY PROVIDING
ADDITIONAL FOCUSED PCPN WED EVE. PCPN WILL SHIFT SEWD OVNGT AND
SHOULD VACATE THE FCST AREA BY MID-MRNG THU.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
MODELS ARE NOW IN BETTER AGREEMENT BUILDING IN HIGH PRESSURE FOR
THE WEEKEND. THIS WOULD MEAN DRY AND COMFORTABLE CONDITIONS FOR
MUCH OF THE LONG TERM.
&&
.AVIATION /21Z TUESDAY THROUGH SUNDAY/...
SHOWER AND THUNDERSTORM COVERAGE WILL EXPAND THROUGH THE EVENING
HOURS. CIGS AND VIS SHOULD STAY IN THE MVFR/VFR RANGE. IF A
TERMINAL IS IMPACTED BY A SHOWER OR STORM THEN A BRIEF PERIOD OF
IFR VIS / CIGS ARE POSSIBLE.
MVFR FG IS POSSIBLE OVERNIGHT THROUGH MID MRNG WED GIVEN HOW MUCH
MOISTURE RESIDES IN THE LLVLS. SHOWERS AND THUNDERSTORMS WILL BE
NUMEROUS WED WITH IFR CONDITIONS EXPECTED FOR A BRIEF PERIOD.
OUTLOOK.../21Z WEDNESDAY THROUGH SUNDAY/...
IFR WEATHER IS POSSIBLE AGAIN THURSDAY IN SHOWERS AND
THUNDERSTORMS ASSOCIATED WITH A COLD FRONT.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...FLASH FLOOD WATCH FROM 8 PM EDT THIS EVENING THROUGH LATE
WEDNESDAY NIGHT FOR MDZ001.
OH...FLASH FLOOD WATCH FROM 8 PM EDT THIS EVENING THROUGH LATE
WEDNESDAY NIGHT FOR OHZ039>041-049-050-059.
FLASH FLOOD WATCH THROUGH LATE WEDNESDAY NIGHT FOR OHZ048-057-
058-068-069.
PA...FLASH FLOOD WATCH FROM 8 PM EDT THIS EVENING THROUGH LATE
WEDNESDAY NIGHT FOR PAZ020-021-029-031-073>076.
WV...FLASH FLOOD WATCH FROM 8 PM EDT THIS EVENING THROUGH LATE
WEDNESDAY NIGHT FOR WVZ001>004-023-041.
FLASH FLOOD WATCH THROUGH LATE WEDNESDAY NIGHT FOR WVZ012-021-
022.
&&
$$
SYNOPSIS...34
NEAR TERM...98/34
SHORT TERM...KRAMAR
AVIATION...98/34
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
359 AM EDT TUE JUL 9 2013
.SYNOPSIS...
A SERIES OF UPPER DISTURBANCES WILL IMPACT THE MID-ATLANTIC REGION
INTO THURSDAY WHILE BERMUDA HIGH PRESSURE PERSISTS OFFSHORE. A COLD
FRONT IS EXPECTED TO MOVE ACROSS THE CENTRAL MID-ATLANTIC FROM THE
WEST LATE THURSDAY INTO FRIDAY BEFORE STALLING OVER THE SOUTHERN
MID-ATLANTIC FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
BERMUDA HIGH REMAINS ANCHORED OVER THE WESTERN ATLANTIC THROUGH
TONIGHT. MID-ATLANTIC REMAINS IN A WESTERLY FLOW ALOFT...WITH
EMBEDDED SHORTWAVES EXPECTED TO AFFECT THE CWA.
RADAR SHOWS ONE AREA OF SHOWERS ACROSS SOUTHWEST PENNSYLVANIA AND
NORTHERN WEST VIRGINIA PRESSING EAST-SOUTHEAST EARLY THIS MORNING.
BASED ON RADAR TRENDS EXPECT THIS LEADING WAVE OF SHOWERS TO AFFECT
LOCATIONS WEST OF THE BLUE RIDGE. THERE IS SOME UNCERTAINTY HOW FAR
EAST THE INITIAL AREA OF SHOWERS MAKES IT BEFORE POSSIBLY
DIMINISHING. HRRR GUIDANCE SUGGESTS THIS LEADING WAVE OF SHOWERS
WEAKENS OVER THE NEXT SEVERAL HOURS...SO LOWER POPS EXIST FURTHER
DOWNSTREAM.
HOWEVER EVEN IF THE LEADING WAVE OF SHOWERS DISSIPATES...SHORTWAVE
OVER OHIO IS FORECAST TO MOVE EAST INTO THE MID-ATLANTIC FOR THIS
AFTERNOON WHICH WILL SUPPORT SOME SHOWERS AND THUNDERSTORMS ACROSS
THE ENTIRE CWA BY THAT TIME.
WITH MORNING CLOUD COVER THIS WILL LIMIT DESTABILIZATION THIS
AFTERNOON. SIMILAR TO YESTERDAY NAM SHOWS MORE CAPE THAN THE
GFS...AND WAS THE BETTER CHOICE. STILL...NAM ONLY EXHIBITS ABOUT
1000 J/KG THIS AFTERNOON ALONG WITH WEAK SHEAR. THEREFORE...AM NOT
EXPECTING ORGANIZED SEVERE CONVECTION BUT LOCALLY STRONGER STORMS
WITH GUSTY WINDS/HEAVY DOWNPOURS CAN/T BE RULED OUT.
MUCH OF THE CONVECTION SHOULD DISSIPATE BY EARLY EVENING AS THE
SHORTWAVE EXITS AND THE SUN SETS. WILL CONTINUE POPS FOR SHOWERS
ACROSS THE NORTHWEST PORTION OF THE CWA HOWEVER AS ANOTHER SHORTWAVE
APPROACHES. FOG PRONE AREAS COULD SEE PATCHY FOG AS
WELL...PARTICULARLY IF SOME CLEARING OCCURS.
MET GUIDANCE PERFORMED BETTER THAN MAV GUIDANCE FOR MAXIMA
YESTERDAY. IT CONTINUES TO BE THE LOWER SET OF GUIDANCE...AND WITH
PLENTY OF CLOUDS TODAY WILL LEAN IN THAT DIRECTION WITH A SLIGHT
UPWARD ADJUSTMENT 1-2 DEG /BUT STILL BELOW MAV/. USED AN EQUAL BLEND
OF BIAS CORRECTED MET/MAV FOR MINIMA.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
WEDNESDAY...A SHORT-WAVE TROUGH SWINGS EAST THROUGH THE MID-ATLANTIC
THROUGH THE DAY. WITH THE BERMUDA HIGH PUMPING TROPICAL MOISTURE
INTO THE REGION...EXPECT DEWPOINTS IN THE LOW 70S AND PWATS OF 2.0
TO 2.2 INCHES WHICH IS NEAR TWO STANDARD DEVIATIONS ABOVE NORMAL.
WITH A FOCUS OF FORCING FROM THE TROUGH AXIS...THERE IS THE
POTENTIAL FOR SEVERE THUNDERSTORMS AND FLASH FLOODING ACROSS THE
AREA. WILL ADD MENTION OF BOTH TO THE HWO. WITH BULK SHEAR LESS THAN
25 KT... FLASH FLOODING SHOULD BE THE GREATEST THREAT. CLOUD COVER
MAY LIMIT MAX TEMPS...WENT WITH A MAV/MET BLEND THAT LEANS TOWARD
MAV...GENERALLY UPR 80S WITH LOW 90S POSSIBLE IN BALT-WASH URBAN
CORRIDOR.
WEDNESDAY NIGHT...INSTABILITY REMAINS THROUGH THE NIGHT WITH AT
LEAST ISOLATED ONGOING OR REDEVELOPING THUNDERSTORMS. MIN TEMPS HIGH
WITH CLOUDS AND MOISTURE...GENERALLY LOW TO MID 70S PER MAV/MET/SREF
BLEND.
THURSDAY...COLD FRONT APPROACHES FROM THE WEST AS LONG WAVE TROUGH
AMPLIFIES AS IT MOVES ACROSS THE MIDWEST STATES. EXPECT MORE
WIDESPREAD THUNDERSTORM ACTIVITY THAN WED WITH THE FRONT
ENTERING THE POTOMAC HIGHLANDS LATE IN THE AFTERNOON. SLIGHTLY MORE
BULK SHEAR THAN WED AND THE FRONTAL FORCING SHOULD INCREASE THE
SEVERE THREAT. SIMILAR TO WED WITH MEX/GMOS BLEND SUGGESTING A
COUPLE DEGREES LESS.
THURSDAY NIGHT...COLD FRONT PUSHES SE THROUGH MOST OF THE CWA BEFORE
STALLING OVER SERN VA WHERE IT WILL PERSIST/UNDULATE THROUGH THE
WEEKEND. ONGOING THUNDERSTORMS WILL BE SHUNTED TO SERN PORTIONS OF
THE CWA...WHERE CHANCE POPS WERE MAINTAINED FOR THE LATE NIGHT. MIN
TEMPS LOW 60S IN THE POTOMAC HIGHLANDS...THEN MID TO UPR 60S WEST
FROM THE SHEN VLY PER MEX/SREF BLEND.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
COLD FRONT REMAINS STALLED OVER THE DELMARVA AND SERN VA THROUGH THE
WEEKEND. THE FRONT MAY RETROGRADE A BIT...RESULTING IN THUNDERSTORMS
INTO THE BALT-WASH METRO...PARTICULARLY FOR SUNDAY. OTW...EXPECT
DRIER CONDITIONS WITH SFC HIGH PRESSURE SHIFTING EAST ACROSS THE NRN
MID-ATLANTIC. TEMPS NEAR NORMAL WITH SOME SUNSHINE.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
SHOWERS MAY REACH MRB EARLY THIS MORNING...BUT CONFIDENCE IS LOW ON
THIS INITIAL BATCH HOLDING TOGETHER AS FAR EAST AS THE HUBS.
SHORTWAVE MOVES THROUGH THIS AFTERNOON...WITH AT LEAST SHRA/TSRA AND
WILL CONSIDER INCLUSION OF VCTS/CB FOR THE NEXT TAF CYCLE.
ACTIVE WEATHER PATTERN FOR WED THROUGH THUR NIGHT WITH HEAVY
THUNDERSTORMS EXPECTED. IFR CONDS IN HEAVIEST ACTIVITY. GENERALLY
LIGHT SSWLY FLOW WED INTO THUR BEFORE A COLD FRONT MOVES THROUGH THE
TERMINALS LATE THURSDAY. COLD FRONT STALLS JUST SE OF DC METROS
FRIDAY INTO THE WEEKEND.
&&
.MARINE...
SOUTHERLY WINDS AROUND BERMUDA HIGH CONTINUES THROUGH TONIGHT.
SHOULD STAY BELOW SCA TODAY...BUT THIS EVENING AND INTO THE NIGHT
THERE IS A BETTER CHANCE OF HIGHER WINDS UP THE BAY ENHANCED BY
CHANNELLING AND WILL RAISE SCA.
SSWLY FLOW INCREASES THROUGH THE DAY WEDNESDAY. JUST THE LOWER SRN
MD PORTION OF THE BAY IN SCA WED MORNING...THEN TO ALL WATERS FOR
THE AFTERNOON THAT IS EXPECTED TO CONTINUE INTO THE EVENING. ACTIVE
WEATHER PATTERN WITH SPECIAL MARINE WARNINGS POSSIBLE UNTIL A COLD
FRONT MOVES THROUGH LATE THURSDAY NIGHT. COLD FRONT WILL STALL NEAR
THE WATERS THROUGH THE WEEKEND...POTENTIALLY CONTINUING THE ACTIVE
WEATHER PATTERN.
&&
.EQUIPMENT...
THE RIVER GAUGE AT FROV2 STILL IS REPORTING ERRONEOUS DATA. WE
HAVE TURNED OFF THE DATA STREAM FROM THIS GAUGE. USE DATA FROM
THIS SITE WITH EXTREME CAUTION. HWVR...THE BAD DATA HAS NOT BEEN
INGESTED INTO RIVER FCSTS.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 2 AM EDT
WEDNESDAY FOR ANZ531>533-539>541.
SMALL CRAFT ADVISORY FROM 2 PM TO 6 PM EDT WEDNESDAY FOR
ANZ530>533-535>542.
SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 PM EDT
WEDNESDAY FOR ANZ534-543.
&&
$$
SYNOPSIS...BPP/BAJ
NEAR TERM...BPP
SHORT TERM...BAJ
LONG TERM...BAJ
AVIATION...BPP/BAJ
MARINE...BPP/BAJ
EQUIPMENT...LWX
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
408 PM EDT TUE JUL 9 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 408 PM EDT TUE JUL 9 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A MAINLY ZONAL PATTERN ACROSS
THE NRN CONUS WITH SEVERAL UPSTREAM SHORTWAVE TROUGHS. THE MOST
PROMINENT SHRTWV WAS LOCATED OVER ERN MT WHILE A WEAKER IMPULSE AND
ASSOCIATED MCS WAS MOVING THROUGH ERN SD. AT THE SFC...A WEAK
FRONTAL BOUNDARY LINGERED ACROSS SRN WI WHILE A STRONGER COLD FRONT
AHEAD OF THE MT SHRTWV EXTENDED FROM NW ONTARIO INTO NRN ND. A WEAK
RIDGE EXTENDED FROM QUEBEC ACROSS LAKE SUPERIOR RESULTING IN
LIGHT/CALM WINDS OVERNIGHT. AREAS OF FOG...LOCALLY DENSE...HAS
DEVELOPED AS ABUNDANT LOW LEVEL MOISTURE LINGERED BELOW AN INVERSION
ABOVE 850 MB.
EXPECT THAT THE MORNING WILL BE DOMINATED BY LOW CLOUDS BUT WITH
DAYTIME HEATING/MIXING THE LOW CLOUDS ACROSS MOST OF THE AREA WILL
THIN OUT ENOUGH BY THIS AFTERNOON FOR TEMPERATURES TO CLIMB INTO THE
LOWER 80S INLAND. SATELLITE TRENDS...SHORTER TERM MODELS AND CAPE
GRADIENT...SUGGEST THAT THE ERN SD MCS WILL TRACK TO THE EAST INTO W
AND SRN WI.
THERE IS SOME UNCERTAINTY REGARDING THE IMPACTS OF THE MCS ON
CONVECTION DEVELOPING FARTHER TO THE NORTH. THE FORCING ASSOCIATED
WITH THE APPROACHING NRN PLAINS SHRTWV WITH 100M HEIGHT FALLS AND
MODERATE 700-300 QVECTOR CONV WILL ALSO BE STRONGEST TO THE NORTH OF
THE CWA. HOWEVER...THE SRN END OF THE SHRTWV SHOULD STILL BE STRONG
ENOUGH TO SUPPORT SCT SHRA/TSRA MOVING FROM NW WI INTO WRN UPPER MI
THIS AFTERNOON AND THROUGH THE REST OF THE CWA THIS EVENING.
EXPECTED MAX TEMPS AND DEWPOINTS INTO THE MID TO UPPER 60S GIVE CAPE
VALUES INTO THE 1K-2K J/KG RANGE...GREATEST WEST CENTRAL. 0-6KM BULK
SHEAR VALUES IN THE 30-35 KNOT RANGE WILL BE MARGINAL FOR STRONG/SVR
ORGANIZED CONVECTION BUT WITH TSRA MOVING THROUGH DURING PEAK
HEATING GIVING DCAPE VALUES IN THE 500-1000 J/KG RANGE...SOME
ISOLATED STRONG/DAMAGING WIND GUSTS MAY BE POSSIBLE WITH ANY
STRONGER STORMS. THE HIGHER PROBABILITIES FOR SVR STORMS REMAINS TO
THE SOUTH WHERE THE INSTABILITY IS GREATEST...PER SPC DAY1 OUTLOOK.
THE SHRA/TSRA ARE EXPECTED TO PROGRESS THROUGH THE AREA MOVING INTO
THE ERN CWA LATE THIS EVENING AND ENDING OVERNIGHT.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 408 PM EDT TUE JUL 9 2013
SFC HIGH PRESSURE WILL MAKE ITS WAY OVER UPPER MICHIGAN FOR THURSDAY
AND FRIDAY...KEEPING WEATHER QUIET FOR THE START OF THE LONG TERM.
WITH 850MB TEMPS 12-15C EXPECT AFTERNOON HIGHS ON THURSDAY AND
FRIDAY TO BE IN THE UPPER 70S AND LOW 80S INLAND. ADDITIONALLY...DRY
AIR ASSOCIATED WITH THIS HIGH /PWATS ROUGHLY 60 PERCENT OF NORMAL/
WILL BRING A NICE BREAK TO THE STICKY HUMID CONDITIONS WEVE
EXPERIENCED THIS PAST WEEK. THOUGH IT WILL BE DRY AND WARM...WITH
THE RIDGE OVERHEAD WINDS WILL REMAIN VERY LIGHT.
THE NEXT CHANCE FOR PRECIPITATION COMES SATURDAY MORNING AND THROUGH
THE FIRST PORTIONS OF THE WORK WEEK. THE SFC HIGH PRESSURE SYSTEM
OVER THE GREAT LAKES SINKS SOUTHEASTWARD TOWARDS THE MID ATLANTIC
STATES AND A LOW PRESSURE SYSTEM MOVES ACROSS THE CANADIAN
PRAIRIE...DRAGGING A WEAK TROUGH ACROSS THE AREA DURING THE DAY
SATURDAY. MODELS HAVE COME INTO DECENT AGREEMENT THROUGH SATURDAY
EVENING...WITH ALL BRINGING PRECIPITATION AHEAD OF THE COLD FRONT
INTO THE WESTERN CWA BY APPROX 12Z SATURDAY MORNING. PWATS AHEAD OF
THE FRONT REACH UP TO 190 PERCENT OF NORMAL AND MUCAPE VALUES ARE
GENERALLY 300-700 J/KG IN THE 12Z SAT-00Z SUN TIME FRAME...AGAIN
MAINLY OVER THE WEST AND CENTRAL PORTIONS OF UPPER MI.
MEANWHILE...THE EASTERN U.P. FOR THE MOST PART REMAINS UNDER THE
INFLUENCE OF A RIDGE EXTENDING FROM THE HIGH PRESSURE THAT SETTLED
OVER THE MID ATLANTIC STATES. BOTH THE GFS/ECMWF HAVE THE RIDGE
STALLING THE EASTWARD PROGRESSION OF THE FRONT UNTIL SUNDAY
NIGHT-MONDAY WHEN A STRONGER SHORTWAVE FORCES IT EASTWARD THROUGH
THE CWA.
DISCREPANCIES AMONGST THE MODELS SHOW UP LATE SATURDAY NIGHT
INTO SUNDAY AS 500MB HIGH PRESSURE SPRAWLS OVER THE CENTRAL CONUS.
CONVECTION DEVELOPS ALONG THE EDGE OF THIS RIDGE UNDER THE MORE
ZONAL FLOW AT 500MB OVER THE NORTHERN PLAINS AND UPPER MICHIGAN. AS
OF NOW...THE ECMWF HAS THE BULK OF THE PRECIPITATION OVER UPPER MI
ALONG WITH A MORE DEFINED SHORTWAVE....HOWEVER THE GFS HAS IT MOVING
FURTHER SOUTH ACROSS MAINLY WI/ALONG THE WI BORDER WITH A LESS
DEFINED SHORTWAVE. OVERALL LOW CONFIDENCE IN MUCH OF ANYTHING THIS
FAR OUT AS WHERE/WHEN CONVECTION DEVELOPS OVER THE NORTHERN PLAINS
AND HOW IT EVOLVES WILL GREATLY INFLUENCE THE FORECAST. KEPT POPS
SIMILAR TO PREVIOUS FORECAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 408 PM EDT TUE JUL 9 2013
THE MAIN ISSUES DURING THIS TAF PERIOD WILL BE FOCUSED ON TS CHANCES
THIS AFTERNOON WITH MVFR TO IFR CONDITIONS DEVELOPING OVERNIGHT.
HAVE PLACED VCTS IN THE IWD TAF AT THE BEGINNING OF THE TAF PERIOD
WITH THUNDERSTORMS APPROACHING THE AREA FROM THE SOUTH. CURRENT
THINKING IS THAT THIS WILL BE THE MAIN AREA OF CONVECTION THIS
AFTERNOON...SHIFTING EASTWARD TO SAW BY 21Z. CMX MAY MISS OUT ON
MOST OF THE CONVECTION DUE TO LINGERING CLOUD COVER AN GREATER
STABILITY. CEILING AND VISIBILITY WILL LOWER THIS EVENING THROUGH
MUCH OF TONIGHT AHEAD OF THE APPROACHING COLD FRONT. IT WOULD NOT BE
OUT OF THE QUESTION FOR A FEW RUMBLES OF THUNDER NEAR THE IWD AND
SAW TAF SITE BEFORE FROPA...BUT DO NOT EXPECT WIDE SPREAD
THUNDERSTORM ACTIVITY. ONCE FRONT PASSES CEILINGS AND VISIBILITY
WILL IMPROVE TO VFR CONDITIONS NEAR DAY BREAK WEDNESDAY. WINDS MAY
BECOME A BIT GUST BEHIND THE COLD FRONT THROUGH THE DAY
WEDNESDAY...WITH GUSTS REACHING NEARLY 25 KNOTS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 408 PM EDT TUE JUL 9 2013
DENSE FOG REMAINS A CONCERN ACROSS LAKE SUPERIOR TODAY.
CLEARING SKIES FOR TUESDAY MORNING SHOULD ALLOW ENOUGH HEATING TO
MIX OUT THE MOST DENSE FOG DURING THE AFTERNOON...AT LEAST CLOSER TO
THE SHORE. PATCHY FOG WILL THEN LINGER INTO WEDNESDAY BEFORE A COLD
FRONT BRINGS DRIER AIR FROM WEST TO EAST ACROSS THE LAKE. WINDS
SHOULD BE LIGHT AND GENERALLY VARIABLE THROUGH TUESDAY EVENING.
THEN...EXPECT WINDS TO VEER TO THE NW AT 15 TO 25 KNOTS...MAINLY
ACROSS THE EAST HALF OF THE LAKE...FOR LATE TUESDAY NIGHT THROUGH
WEDNESDAY. HIGH PRESSURE WILL THEN BUILD INTO THE AREA THURSDAY
THROUGH SATURDAY AND BRING LIGHT WINDS UNDER 15 KNOTS FOR MUCH OF
THE TIME PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KEC
LONG TERM...MCD
AVIATION...KEC
MARINE...KEC
AREA FORECAST DISCUSSION
NWS GAYLORD MI
401 PM EDT TUE JUL 9 2013
.SYNOPSIS...
ISSUED AT 401 PM EDT TUE JUL 9 2013
CHANCES OF RAIN SHOWERS AND THUNDERSTORMS WILL OCCUR TONIGHT INTO
WEDNESDAY MORNING AS A COLD FRONT APPROACHES THE REGION. BEHIND THE
FRONT...HIGH PRESSURE WILL BEGIN TO BUILD IN BY LATE
WEDNESDAY...BRINGING COOLER AND LESS HUMID CONDITIONS FOR MIDWEEK. A
WARMING TREND WILL THEN FOLLOW FOR LATE IN THE WEEK INTO THE
UPCOMING WEEKEND.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 401 PM EDT TUE JUL 9 2013
AN ADMITTEDLY FRUSTRATING FORECAST THIS EVENING...WITH CONFIDENCE
DWINDLING ABOUT THE POTENTIAL FOR CONVECTION ACROSS THE CWA...
DESPITE WHAT SHOULD (THEORETICALLY AT LEAST) BE A DECENT SETUP.
EARLY AFTERNOON ANALYSIS REVEALS A PAIR OF SHORTWAVES TRAVERSING A
SEASONABLY STRONG JET STREAM FLOW ACROSS THE NORTHERN TIER...WITH
THE FIRST OF THESE WAVES JUST NOW ENTERING WESTERN WISCONSIN. THIS
FEATURE HAS BEEN RESPONSIBLE FOR A RATHER LONG-LIVED AXIS OF
CONVECTION ALL ACROSS THE UPPER MIDWEST OVER THE PAST 12
HOURS...WITH THIS ACTIVITY JUST NOW WORKING ACROSS SOUTHERN LAKE
MICHIGAN. THE AIRMASS ACROSS NORTHERN LOWER REMAINS STUBBORNLY
CAPPED THANKS TO A WARM NOSE UP AROUND 750MB PER BOTH RUC AND
OBSERVED SOUNDINGS...WITH EARLIER THICK CLOUD COVER EFFECTIVELY
LIMITING HEATING AND THUS INSTABILITY. ALL THE WHILE...THE BEST
BOUNDARY LAYER MOISTURE REMAINS LAID OUT OVER THE SOUTHERN LAKES
ALONG A SUBTLE WARM FRONT...WITH MUCAPE VALUES OF 1500-3000 J/KG
NOTED IN THE VICINITY OF THIS FEATURE. NOT SURPRISINGLY...CONVECTION
IS DOING THE FAMOUS NORTHERN MICHIGAN SPLIT AS OUR AIRMASS IS JUST
PLAIN GARBAGE...FOR LACK OF A BETTER TERM...FEATURING ONLY MUCAPE
VALUES PERHAPS PUSHING 700J/KG AT BEST AND THE AFOREMENTIONED CAP.
MEANWHILE...A SECONDARY/STRONGER UPPER WAVE IS NOTED DIVING INTO THE
NORTHERN PLAINS...HERALDING THE ARRIVAL OF A MUCH COOLER AIRMASS...
WITH AN ASSOCIATED COLD FRONT DRAPED OVER NORTHWEST MINNESOTA AS OF
19Z.
INTO LATE AFTERNOON AND THE EVENING...APPROACH OF LEAD UPPER WAVE
WILL MANDATE AT LEAST A CONTINUED CHANCE FOR SHOWERS AND A FEW
STORMS...THOUGH HONESTLY JUST NOT FEELING ANY BIG RAIN CHANCES...AS
THE REAL BEEFY CONVECTION SHOULD GET GOING OVER THE SOUTHERN LAKES.
AS SUCH...AND GIVEN RADAR TRENDS AND STRONG LACK OF ANY UPSTREAM
ADDITIONAL ACTIVITY (JUST SOME FLAT CU ACROSS WISCONSIN)...HAVE TO
BELIEVE SCATTERED ACTIVITY WILL JUST ABOUT DO IT...AS PERHAPS WE MAY
GET LUCKY ENOUGH TO BUBBLE UP A FEW ADDITIONAL SHOWERS WITH THE
INCOMING VORT. NO SEVERE WX THREAT WITH EFFECTIVE SHEAR ONLY ABOUT
20 KNOTS.
A BIGGER QUESTION COMES TONIGHT AS THE SECONDARY TROUGH AND COLD
FRONT ARRIVE. IT WOULD BE NICE TO SEE AT LEAST A LITTLE UPSTREAM
ACTIVITY WITH THIS FEATURE...BUT ALAS THERE IS NOTHING AT THE
MOMENT...WITH NOTABLE CAPPING IN PLACE BEHIND THE LEAD WAVE. STILL
NOT OUT OF THE QUESTION SOME SHOWERS OR A STORM COULD DEVELOP WITH
THE UPPER TROUGH THROUGH THE EVENING...PERHAPS PUSHING INTO OUR AREA
OVERNIGHT. HAVING SAID THAT...CONFIDENCE IS LOW ENOUGH TO JUST
BARELY MAINTAIN SOME CHANCE POPS AT THIS POINT...WITH MAYBE A FEW
LINGERING SHOWERS INTO WEDNESDAY MORNING ACROSS EASTERN COUNTIES.
FAIRLY LIGHT FLOW IN ADVANCE OF AND SHALLOW NATURE OF INITIAL COLD
FRONT MAY AGAIN ALLOW FOR LOW CLOUDS AND SOME FOG TO DEVELOP
OVERNIGHT...PARTICULARLY AS THE FLOW VEERS MORE WESTERLY AND TRIES
TO PUSH LAKE MICHIGAN GRUNGE BACK ON LAND.
WEDNESDAY NOT LOOKING TOO BAD...WITH ANY PRECIP THREAT DONE BY
15Z...BUT PROBABLY SOME PESKY CU/STRATOCU AS MUCH COLDER AIR BLEEDS
IN ALOFT. TEMPS NOTABLY COOLER...WITH HUMIDITY LEVELS DIVING AS DEW
POINTS MIX INTO THE 50S. COOLER WITH HIGHS MAINLY IN THE 70S...BUT
COULD SNEAK IN A FEW LOW 80S SOUTHEAST COUNTIES ON A GUSTY NORTHWEST
FLOW...WITH WIND GUSTS UP TO 25 KNOTS EXPECTED.
&&
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 401 PM EDT TUE JUL 9 2013
RECENT TRENDS...TEMPERATURES: 1-3C ABOVE NORMAL OVER THE LAST WEEK
WITH MOST RECENT WARM SPELL...STATE HAS BEEN MOSTLY SPLIT BETWEEN
ABOVE NORMAL TEMPERATURES NORTH AND COOLER TEMPERATURES OVER
SOUTHERN LOWER WHICH IS THE NORTHERN EXTENT OF A LARGER AREA OF
BELOW NORMAL TEMPERATURES TO START JULY ACROSS THE MID/LOWER
MISSISSIPPI VALLEY/OHIO VALLEY AND INTO THE SOUTHEAST THANKS TO
RECENT HEAVY RAINFALL. PRECIPITATION/HYDROLOGY: BAND OF MUCH
NEEDED RAINFALL YESTERDAY BETWEEN THE M-32 AND M-55 CORRIDORS WITH
WIDESPREAD 0.50+ INCH AMOUNTS AND AREAS OF 1-2 INCH AMOUNTS.
EASTERN UPPER/TIP OF THE MITT STILL DRY THOUGH...LAST MEASURABLE
PRECIP IN THE SAULT WAS JUNE 28. 30 DAY STANDARDIZED PRECIP INDEX
CONTINUES ON A DRIER TRENDS ESPECIALLY ACROSS EASTERN UPPER.
NORTHERN MICHIGAN SOIL MOISTURE CONTINUES TO DRY OUT (STILL NEAR
NORMAL...ABOVE NORMAL NOW CONFINED TO CENTRAL/SOUTHERN LOWER
MICHIGAN). SEVEN DAY MEAN DISCHARGE ON AREA RIVERS MOSTLY NEAR
NORMAL. LATEST GREAT LAKES LEVELS FORECAST FROM THE ARMY CORPS
SHOWS LAKES MICHIGAN/HURON CURRENTLY ABOUT 2 FEET BELOW NORMAL...
WITH LITTLE IMPROVEMENT FORECAST THROUGH THE FALL.
LARGE SCALE PATTERN/FORECAST...FLAT/EXPANSIVE RIDGE SPANS THE
SOUTHERN CONUS AND EXTENDS EAST ACROSS THE SUBTROPICAL ATLANTIC TO
THE IBERIAN PENINSULA. MAINLY ZONAL BAND OF WESTERLIES TO THE NORTH
OF THIS RIDGE CROSSING THE NORTHERN TIER OF STATES AND ACROSS THE
GREAT LAKES...ALL PART OF A LOW AMPLITUDE 4/5 WAVE HEMISPHERIC
PATTERN. SHORT WAVE TROUGH MOVING THROUGH THIS BAND OF WESTERLIES
ACROSS THE HIGH PLAINS TODAY IS FORECAST TO STRENGTHEN AS IT MOVES
INTO THE GREAT LAKES WEDNESDAY AND HOOKS UP WITH HIGH LATITUDE
TROUGHING OVER THE ARCTIC TO COOL THINGS OFF FOR A COUPLE OF DAYS.
THIS TROUGH WILL SERVE TO SPLIT THE SOUTHERN CONUS RIDGE...ALLOWING
HIGHER HEIGHTS TO CONSOLIDATE OVER THE CENTRAL/SOUTHERN PLAINS BY
FRIDAY (AND OPEN UP A CHANNEL TO DRAW TROPICAL CYCLONE "CHANTAL" TO
THE NORTHWEST TOWARD THE SOUTHEASTERN U.S.). RISING HEIGHTS APPEAR
TO BE IN THE OFFING FOR THE UPPER LAKES HEADING INTO THE WEEKEND AS
UPPER RIDGE AXIS POKES ITS WAY NORTHEAST...THEN PERHAPS SOME SORT OF
BOUNDARY THAT SETTLES IN EARLY NEXT WEEK WITH A FAIRLY STRONG HEIGHT
GRADIENT ACROSS CANADA.
FORECAST AREA SHOULD BE FIRMLY WITHIN POST-FRONTAL AIR MASS BY
WEDNESDAY EVENING AS NORTHWEST BOUNDARY LAYER FLOW PULLS COOLER/
DRIER AIR ACROSS THE UPPER LAKES. TRAILING SHORT WAVE TROUGH WILL
FOLLOW LATER WEDNESDAY NIGHT BUT HEIGHT RISES ALOFT AND RISING
SURFACE PRESSURES TO ARRIVE THURSDAY...WITH HIGH PRESSURE HOLDING ON
INTO FRIDAY. SO FORECAST CONCERNS IN THE NEAR TERM
WEDNESDAY NIGHT THROUGH FRIDAY...WEATHER: NOT MUCH AT THIS POINT.
SHORT WAVE TROUGH SWINGS THROUGH WEDNESDAY NIGHT...BUT MAY NOT HAVE
MUCH MORE THAN SOME MID CLOUD WITH IT. LOW LEVEL THERMAL TROUGH
WILL MOVE THROUGH LOWER MICHIGAN DURING THE FIRST HALF OF
THURSDAY...MAY ALLOW FOR SOME DIURNALLY FORCED CLOUDS TO POP ACROSS
INTERIOR NORTH CENTRAL/NORTHEAST LOWER. BEYOND THAT WEATHER
CONCERNS MINIMAL THURSDAY NIGHT (CHILLY) AND FRIDAY.
TEMPERATURES...WEDNESDAY NIGHT LOWS MAINLY IN THE 50S...HIGHS
THURSDAY PROBABLY A COUPLE DEGREES BELOW SEASONABLE NORMS (MOSTLY
70S). GOOD RADIATIONAL COOLING NIGHT IN STORE THURSDAY NIGHT...
FRIDAY MORNING LOWS DOWN IN THE 40S AS A RESULT. HIGHS FRIDAY
EXPECTED TO BE CLOSER TO NORMAL (UPPER 70S/LOWER 80S).
WINDS...NORTHWEST 10-15 TO START WEDNESDAY EVENING THEN DIMINISHING.
NORTH/NORTHWEST 5-15MPH DURING THE DAY THURSDAY THEN BECOMING MOSTLY
CALM THURSDAY NIGHT. FRIDAY WINDS SOUTH 5-10MPH EASTERN UPPER...
MOSTLY LIGHT/VARIABLE SOUTH OF THE BRIDGE WITH PREDOMINANT LAKE
BREEZE CIRCULATIONS RESULTING IN ONSHORE FLOW ALONG THE
LAKESHORES.
EXTENDED FORECAST (SATURDAY THROUGH TUESDAY)...WILL CONTINUE TO WARM
UP SATURDAY AND EXPECTING ANOTHER DRY DAY WITH HIGHS WELL INTO THE
80S. RAIN CHANCES MAY START TO INCREASE SATURDAY NIGHT INTO SUNDAY
ESPECIALLY FARTHER NORTH WHERE MAY SEE INCREASED FOCUS ALONG A LOW
LEVEL JET. AFTER THAT...HEIGHT FALLS SPREAD INTO CENTRAL/EASTERN
CANADA WITH AN ASSOCIATED FRONTAL BOUNDARY FORECAST TO GET STRETCHED
OUT IN THE VICINITY OF THE UPPER LAKES. WHETHER SAID BOUNDARY DROPS
IN CLOSE ENOUGH TO FOCUS SHOWER/THUNDERSTORM CHANCES EARLY NEXT WEEK
IS UNCERTAIN...MAY TRY TO GO DRY MONDAY AND START TUESDAY OUT WITH
SOME RAIN CHANCES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 106 PM EDT TUE JUL 9 2013
A VARIETY OF CONDITIONS WILL CONTINUE ACROSS THE TAF SITES THROUGH
LATE AFTERNOON...WITH THE WORST OF THEM AROUND KAPN WHERE IFR
STRATUS WILL GRADUALLY LIFT TO MVFR. WILL BE WATCHING A LINE OF
SHOWERS AND STORMS TRYING TO CROSS THE LAKE INTO LATE
AFTERNOON...AND SUSPECT THIS FEATURE HAS A GOOD CHANCE OF
SURVIVAL...SO HAVE PUSHED UP ARRIVAL TIME BY MANY HOURS...THOUGH
WITH PREDOMINANTLY VFR CONDITIONS EXPECTED (OUTSIDE OF SOME LOCAL
IFR FOR A FEW MINUTES IN HEAVY RAIN). NOT SURE IF WE WILL BE ABLE
TO KICK OFF ANYTHING ELSE OVERNIGHT AS A COLD FRONT
APPROACHES...BUT STARTING TO HAVE MY DOUBTS...SO WILL REMOVE ALL
PRECIP BY 03-06Z AT THE LATEST. INSTEAD...REMAINING MOIST AIRMASS
SHOULD GO INTO MORE FOG/STRATUS PRODUCTION...WITH THE EXPECTATION
OF MANY SITES ENDING UP IFR ONCE AGAIN. WINDS WILL BE LIGHT
THROUGH MUCH OF THE NIGHT...BUT SHIFT TO THE WEST AND BECOME GUSTY
UP TO 25 KNOTS ON WEDNESDAY.
&&
.MARINE...
ISSUED AT 401 PM EDT TUE JUL 9 2013
FAIRLY LIGHT AND VARIABLE FLOW WILL CONTINUE ON THE GREAT LAKES FOR
MUCH OF TONIGHT...AS AREAS OF FOG AND LOW CLOUDS ALSO PERSIST. WINDS
WILL SHIFT ABRUPTLY OUT OF THE WEST TO NORTHWEST ON WEDNESDAY...WITH
SMALL CRAFT ADVISORY CONDITIONS EXPECTED ACROSS PARTS OF THE
NEARSHORE WATERS...MAINLY THROUGH THE STRAITS AND ACROSS NORTHERN
LAKE HURON AND WHITEFISH BAY. THOSE GUSTY CONDITIONS WILL SLOWLY
ABATE INTO WEDNESDAY NIGHT...WITH AN EXTENDED PERIOD OF LIGHT WINDS
AND FAIRLY LOW WAVES FORESEEN TO WRAP UP THE WORK WEEK AS HIGH
PRESSURE DRIFTS OVER THE WATERS.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
SYNOPSIS...NTS
SHORT TERM...LAWRENCE
LONG TERM...JPB
AVIATION...LAWRENCE
MARINE...LAWRENCE
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
126 PM EDT TUE JUL 9 2013
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 335 AM EDT TUE JUL 9 2013
MOST OF THE DAY TODAY SHOULD SEE A GOOD DEAL OF SUNSHINE AND VERY
WARM AND HUMID TEMPERATURES AFTER MORNING LOW CLOUDS AND FOG
DISSIPATE. THERE WILL BE A SLIGHT CHANCE OF A STORM DURING THE
AFTERNOON HOURS. THE BETTER CHANCE OF MORE WIDESPREAD SHOWERS AND
STORMS WILL COME TOWARD AND AFTER MIDNIGHT TONIGHT AS A WAVE OF LOW
PRESSURE MOVES THROUGH THE AREA.
THE CHANCE OF RAIN WILL DIMINISH THROUGH THE DAY ON WEDNESDAY AS A
COLD FRONT PUSHES SOUTH THROUGH THE AREA. TEMPERATURES WILL BE A BIT
COOLER WEDNESDAY AFTERNOON. EVEN COOLER TEMPERATURES AND DRY
CONDITIONS WILL BE FOUND FOR THE REMAINDER OF THE WEEK BEFORE WE
START TO WARM UP AGAIN THIS COMING WEEKEND.
&&
.UPDATE...
ISSUED AT 1236 PM EDT TUE JUL 9 2013
I HAVE UPDATED OUR GRIDS TO SPEED UP THE TIMING ON THE CONVECTION
ASSOCIATED WITH THE MAIN UPPER WAVE COMING THROUGH THE CWA TO THE
6 PM TO 10 PM TIME FRAME. THIS IS BASED ON TIMING THE WATER VAPOR
IMAGE LOOPS...THE TIMING ON THE 12Z NAM...GFS...RAP AND THE HRRR
AS FAR OUT AS IT GOES. BASED ON THE WATER VAPOR IMAGE LOOPS THE
BACK EDGE GETS TO THE LAKE SHORE BY 8 PM AND THE
JACKSON...LANSING...ALAMA AREA BY 10 PM. THIS SUGGESTS THE STORM
THREAT WILL BE LARGELY OVER BY 10 PM SO I HAVE LIKELY POPS DURING
6 PM TO 10 PM TIME FRAME BUT HAVE ONLY CHANCE POPS AFTER THAT THROUGH
8 AM WEDNESDAY. IF CURRENT TRENDS CONTINUE I WOULD LOWER THE POPS
AFTER MIDNIGHT TO BELOW 20 PERCENT.
THE LIFT IN THE DGZ ON THE RAP MODEL CONTINUES TO BE THE BEST
FEATURE THAT CORRELATES TO THE LOCATION OF THE LIGHTING TODAY.
THAT BRINGS THE MAIN LINE OF STORMS THROUGH THE CWA FROM 8 PM
(WEST CWA) TILL 10 PM (EAST CWA). HOWEVER THERE IS THE SUGGESTION
THERE COULD BE A FEW STORMS DEVELOPING ON THE WARM FRONT...WEST OF
JXN ALONG INTERSTATE 94 BY 4 PM. THOSE STORMS SHOULD HEAD
NORTHEAST TOWARD LANSING BY 5 TO 6 PM.
MODEL SOUNDING MLCAPES ARE FORECAST TO BE IN THE 1500 TO 3000
J/KG RANGE BUT THE DEEP LAYER SHEAR AHEAD OF THE FRONT IS UNDER 25
KNOTS SO I DO NOT EXPECT AN ORGANIZED SEVERE STORM OUTBREAK WITH
THIS....JUST SOME ISOLATED WIND DAMAGE REPORTS. WITH THE FREEZING
LEVEL NEAR 15,500 FT AND THE -20 NEAR 26,000 FT... HAIL WOULD BE
LESS OF A THREAT BUT THERE IS A FAIR AMOUNT OF CAPE IN THE -10 TO
-20C LAYER SO I CAN NOT TOTALLY RULE IT OUT.
WITH THE FASTER MOVEMENT OF THE SYSTEM TEMPERATURES MAY NOT GET TO
90 DEGREES AFTER ALL SINCE THE CLOUDS WILL BE MOVING IN SHORTLY
(BASED ON VISIBLE AND IR LOOPS). STILL WE SHOULD SEE MID TO UPPER
80S INLAND WITH NO PROBLEM.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 335 AM EDT TUE JUL 9 2013
THE MAIN ISSUE IN THE SHORT TERM IS FOG THIS MORNING...THEN STORM
POTENTIAL AND SEVERE THREAT FOR LATE TODAY AND TONIGHT.
A FAIR AMOUNT OF FOG AND LOW CLOUDS HAVE DEVELOPED OVER THE NRN
SECTION OF THE CWFA EARLY THIS MORNING. SOME OF THIS IS STARTING TO
DEVELOP FURTHER SOUTH AS A WEAK SFC TROUGH CRAWLING SOUTH ACROSS THE
AREA IS LIKELY BEING OVERRUN A BIT JUST OFF THE SFC AND WITH THE
HUMID AIR MASS IN PLACE. WE DO EXPECT THAT THIS WILL DISSIPATE
DURING THE MID MORNING HOURS AS THE STRONG SUN ANGLE WORKS ON THE
SHALLOW LAYER OF MOISTURE.
WE EXPECT TO SEE A GOOD DEAL OF SUNSHINE AFTER THE LOW CLOUDS AND
FOG DISSIPATE. THE AREA WILL BE UNDER THE INFLUENCE OF SHORT WAVE
RIDGING ALOFT BETWEEN THE DEPARTING WAVE FROM YESTERDAY AND THE NEXT
WAVE EXPECTED TONIGHT. FCST SOUNDINGS SHOW A WARM LAYER BETWEEN
850-700MB THAT SHOULD CAP MOST IF NOT ALL CONVECTIVE DEVELOPMENT
THROUGH ALMOST 00Z. WE CAN NOT RULE OUT AN ISOLATED SHOWER/STORM
DEVELOPING ALONG A BOUNDARY LIKE A LAKE BREEZE. THAT SAID...THE LOW
LEVEL FLOW LOOKS FAIRLY DIVERGENT DURING THE DAY TODAY WHICH SHOULD
LIMIT ANY DEVELOPMENT ALSO.
THE AREA STILL LOOKS LIKE IT IS ON TRACK FOR A BATCH OF SHOWERS AND
STORMS TO MOVE THROUGH TONIGHT. THE BEST CHANCE WILL OCCUR ALONG AND
SOUTH OF INTERSTATE 96. OUR FOCUS IS ON THE SHORT WAVE PRODUCING
CONVECTION ACROSS THE DAKOTAS...AND THE EVENTUAL LLJ THAT IS
EXPECTED TO DEVELOP THIS EVENING/OVERNIGHT.
WE DO EXPECT THE SHORT WAVE TO MOVE INTO THE AREA TOWARD 06Z. IT
SEEMS THAT THE CONVECTION ACROSS THE DAKOTAS SHOULD SLOWLY MOVE
THROUGH THE DAY. WE COULD SEE IT INTENSIFY A BIT IN WISCONSIN THIS
AFTERNOON AS IT ENCOUNTERS BUILDING INSTABILITY THERE. THIS LINE
WILL LIKELY DIMINISH SOME AS IT HEADS TOWARD OUR CWFA TONIGHT WITH
THE LOSS OF DIURNAL INSTABILITY.
WHAT WE WILL SEE IS THE LLJ INCREASE A BIT AND THE NOSE BE AIMED AT
THE SRN HALF OF THE CWFA BY 06Z. THIS SHOULD HELP MAINTAIN A FAIRLY
DECENT AREA OF SHOWERS AND STORMS THAT WOULD LAST INTO THE DAYBREAK
HOURS ON WED BEFORE MOVING OUT. SEVERE THREAT DOES NOT SEEM VERY
IMPRESSIVE DUE TO THE LATE NIGHT TIME FRAME THE CONVECTION WOULD BE
MOVING IN. FCST SOUNDINGS INDICATE THAT THE CAPE IN THE -10 TO -30C
LAYER IS NOT REAL ABUNDANT. DEEP LAYER CLOUD LAYER SHEAR IS ON THE
LOWER SIDE AROUND 20-25 KNOTS OR SO. MOST OF THE STORMS WOULD BE
ELEVATED WITH SOME POSSIBILITY OF SOME WINDS MAKING IT DOWN WITH
SOME RESIDUAL LOW LEVEL INSTABILITY.
WE FEEL THAT IF THE STORMS MOVE THROUGH AS EXPECTED TONIGHT...MOST
OF THE CWFA WILL BE WORKED OVER ENOUGH FOR WED THAT THE THREAT OF
STORMS AND SEVERE WEATHER IS LOW. IT WILL TAKE A WHILE TO BUILD UP
THE INSTABILITY...AND THE FRONT SHOULD CLEAR THE CWFA BY PEAK
HEATING. THE BEST CHC FOR STORMS WILL BE DOWN SOUTH WHERE LOCATIONS
DO NOT SEE MCS ACTIVITY TONIGHT.
WE WILL SEE SKIES CLEAR THEN WED EVENING AND CONTINUE THROUGH THU AS
DRIER AND COOLER AIR MOVES IN. A SHORT WAVE DOES MOVE THROUGH FROM
THE NW ON THU...HOWEVER THE AIR SHOULD BE DRY ENOUGH AND WE WILL BE
ON THE DOWNSTREAM SIDE OF THE LONG WAVE RIDGE TO OUR WEST TO KEEP US
DRY.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 335 AM EDT TUE JUL 9 2013
THE ARRIVAL OF MID LEVEL RIDGING EARLY IN THE PERIOD SUPPORTS A DRY
PATTERN FOR THE REGION THEN. SUBSIDENCE IS SEEN ON BUFKIT OVERVIEWS
AND MOISTURE PROFILES REMAIN DRY THROUGH SAT. A WARM AIR ADVECTION
PATTERN SETS UP BY SUNDAY AND PWAT VALUES WILL BE ON THE INCREASE.
A WEAKENING SURFACE FRONT SLIPS DOWN FROM THE NORTHWEST SUNDAY NIGHT
INTO MONDAY. WITH SOME ELEVATED/SURFACE INSTABILITY ALONG OR AHEAD
OF THE FRONTAL ZONE...THERE COULD BE A FEW STORMS.
THE BELOW NORMAL TEMPERATURES TO START THE PERIOD TRANSITION TO
ABOVE NORMAL VALUES FOR THE END OF THE PERIOD. TEMPERATURE VALUES
AT 925 MB CLIMB INTO THE LOW TO MID 20 DEG C RANGE SUNDAY. WITH
SOME SUN...WE SHOULD EASILY REACH THE MID 80S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 126 PM EDT TUE JUL 9 2013
MAIN CONCERN IS TIMING THUNDERSTORMS THIS AFTERNOON. BELIEVE
STORMS WILL DEVELOP OVER THE NEXT H0UR ALONG AND SOUTH OF
INTERSTATE 94 AND SPREAD EAST-NORTHEAST...AFFECTING MAINLY THE
AZO...BTL...JXN TERMINALS.
A SECOND WAVE OF EASTWARD MOVING STORMS IS EXPECTED IN THE 00-03Z
TIMEFRAME. IT APPEARS THAT LOW CLOUDS WILL AGAIN BE A CONCERN
AFTER MIDNIGHT BEHIND THESE STORMS. ALTHOUGH NOT MENTIONED IN THE
TAFS...CLEARING OF LOW CLOUDS COULD BE FAIRLY RAPID LATE WEDNESDAY
MORNING.
&&
.MARINE...
ISSUED AT 335 AM EDT TUE JUL 9 2013
NO HEADLINES WILL BE ISSUED WITH THIS FCST PACKAGE...HOWEVER WE ARE
LOOKING AT FOG POTENTIAL THROUGH TONIGHT...ROUGH WEATHER TONIGHT
WITH A POSSIBLE ROUND OF STORMS...AND THEN SOME DECENT WINDS
POSSIBLE WED BEHIND THE FRONT.
THE LIGHT GRADIENT OVER THE LAKE THIS MORNING ALONG WITH THE HUMID
AIR MASS OVER THE SOMEWHAT COOL WATER IS LIKELY PRODUCING SOME FOG.
WEBCAMS SHOW SOME PLACES SEEING FOG WHILE OTHERS ARE NOT. WE DO NOT
FEEL CONFIDENT ENOUGH AT THIS TIME TO ISSUE A MARINE FOG ADVISORY...
HOWEVER IT IS SOMETHING WE WILL NEED TO MONITOR.
WINDS AHEAD OF THE WAVE MOVING IN TONIGHT WILL HAVE THE POTENTIAL TO
INCREASE THE WINDS AND WAVES SOME TONIGHT. THE BIGGER THREAT WILL
LIKELY BE THE STORMS THAT ARE ANTICIPATED. THE BEST WIND WILL COME
WITH ANY STORMS. A DECENT NW WIND COULD DEVELOP LATE WED AFTERNOON
BEHIND THE FRONT THAT PUSHES THROUGH. A SMALL CRAFT ADVISORY MAY BE
NEEDED FOR THAT PERIOD.
&&
.HYDROLOGY...
ISSUED AT 335 AM EDT TUE JUL 9 2013
THE MAIN PERIOD OF CONCERN AS FAR AS HYDRO IS CONCERNED IS THE
TONIGHT PERIOD. WE WILL SEE PRECIPITABLE WATER INCREASE TO AROUND
2.00 INCHES THIS EVENING AHEAD OF THE WAVE THAT WILL MOVE THROUGH
THE AREA. THIS WILL PROVIDE THE POTENTIAL OF HEAVY DOWNPOURS ACROSS
THE AREA. WE DO NOT ANTICIPATE SIGNIFICANT WIDESPREAD ISSUES AS THIS
WAVE THAT MOVES THROUGH SHOULD BE RATHER PROGRESSIVE. AMOUNTS WILL
LIKELY BE A QUARTER TO THREE QUARTERS OF AN INCH OF RAINFALL FOR
BASIN AVERAGES...WITH SOME LOCAL AREAS SEEING 1-2 INCHES OF RAIN.
URBAN AND SMALL STREAM ISSUES WILL BE THE MAIN THREAT.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...MJS
AVIATION...TJT
HYDROLOGY...NJJ
MARINE...NJJ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
117 PM EDT TUE JUL 9 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 525 AM EDT TUE JUL 9 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A MAINLY ZONAL PATTERN ACROSS
THE NRN CONUS WITH SEVERAL UPSTREAM SHORTWAVE TROUGHS. THE MOST
PROMINENT SHRTWV WAS LOCATED OVER ERN MT WHILE A WEAKER IMPULSE AND
ASSOCIATED MCS WAS MOVING THROUGH ERN SD. AT THE SFC...A WEAK
FRONTAL BOUNDARY LINGERED ACROSS SRN WI WHILE A STRONGER COLD FRONT
AHEAD OF THE MT SHRTWV EXTENDED FROM NW ONTARIO INTO NRN ND. A WEAK
RIDGE EXTENDED FROM QUEBEC ACROSS LAKE SUPERIOR RESULTING IN
LIGHT/CALM WINDS OVERNIGHT. AREAS OF FOG...LOCALLY DENSE...HAS
DEVELOPED AS ABUNDANT LOW LEVEL MOISTURE LINGERED BELOW AN INVERSION
ABOVE 850 MB.
EXPECT THAT THE MORNING WILL BE DOMINATED BY LOW CLOUDS BUT WITH
DAYTIME HEATING/MIXING THE LOW CLOUDS ACROSS MOST OF THE AREA WILL
THIN OUT ENOUGH BY THIS AFTERNOON FOR TEMPERATURES TO CLIMB INTO THE
LOWER 80S INLAND. SATELLITE TRENDS...SHORTER TERM MODELS AND CAPE
GRADIENT...SUGGEST THAT THE ERN SD MCS WILL TRACK TO THE EAST INTO W
AND SRN WI.
THERE IS SOME UNCERTAINTY REGARDING THE IMPACTS OF THE MCS ON
CONVECTION DEVELOPING FARTHER TO THE NORTH. THE FORCING ASSOCIATED
WITH THE APPROACHING NRN PLAINS SHRTWV WITH 100M HEIGHT FALLS AND
MODERATE 700-300 QVECTOR CONV WILL ALSO BE STRONGEST TO THE NORTH OF
THE CWA. HOWEVER...THE SRN END OF THE SHRTWV SHOULD STILL BE STRONG
ENOUGH TO SUPPORT SCT SHRA/TSRA MOVING FROM NW WI INTO WRN UPPER MI
THIS AFTERNOON AND THROUGH THE REST OF THE CWA THIS EVENING.
EXPECTED MAX TEMPS AND DEWPOINTS INTO THE MID TO UPPER 60S GIVE CAPE
VALUES INTO THE 1K-2K J/KG RANGE...GREATEST WEST CENTRAL. 0-6KM BULK
SHEAR VALUES IN THE 30-35 KNOT RANGE WILL BE MARGINAL FOR STRONG/SVR
ORGANIZED CONVECTION BUT WITH TSRA MOVING THROUGH DURING PEAK
HEATING GIVING DCAPE VALUES IN THE 500-1000 J/KG RANGE...SOME
ISOLATED STRONG/DAMAGING WIND GUSTS MAY BE POSSIBLE WITH ANY
STRONGER STORMS. THE HIGHER PROBABILITIES FOR SVR STORMS REMAINS TO
THE SOUTH WHERE THE INSTABILITY IS GREATEST...PER SPC DAY1 OUTLOOK.
THE SHRA/TSRA ARE EXPECTED TO PROGRESS THROUGH THE AREA MOVING INTO
THE ERN CWA LATE THIS EVENING AND ENDING OVERNIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 525 AM EDT TUE JUL 9 2013
AFTER A FEW DAYS OF WARM AND ACTIVE WEATHER WITH POCKETS OF HEAVY
RAIN OVER MAINLY WESTERN HALF OF CWA...DEVELOPING TROUGHING ALOFT
ACROSS THE GREAT LAKES AND SFC HIGH ON THE WESTERN EDGE OF THE
TROUGH ALOFT WILL BRING QUIET AND COOLER WEATHER MID TO LATE WEEK.
WARMER TEMPERATURES AND INCREASING SHRA/TSRA CHANCES RETURN FOR THE
WEEKEND AS UPPER HEIGHTS BECOME MORE ZONAL.
OVERALL AGREEMENT THAT BEST CHANCE OF SHRA/TSRA ON WEDNESDAY WILL
BE 12-15Z OVER THE FAR EASTERN CWA. STRONGER TSRA STILL POSSIBLE
WITH MUCAPE UP TO 800J/KG. BETTER SHOT FOR SVR WILL BE FARTHER
SOUTH OVER SOUTHERN WI/NORTHERN IL CLOSER TO WEST-EAST FRONTAL
BOUNDARY AND ON NORTHERN GRADIENT OF HIGHER MLCAPES OVR 1000J/KG.
ANY CHANCES OF SHRA/TSRA OVER EAST QUICKLY END THROUGH MORNING AS
STRONG DEEP LAYER Q-VECTOR DIVERGENCE/SUBSIDENCE SURGES ACROSS
UPPER GREAT LAKES. PRESSURE GRADIENT BRIEFLY BECOMES TIGHT BTWN
THE EXITING LOW PRESSURE TROUGH AND HIGH PRESSURE BUILDING OVER
THE PLAINS. EXPECT BRIEF BUILDING WAVES AND INCREASED SWIM RISK
FOR WEDNESDAY OVER THE LK SUPERIOR BEACHES OF ALGER COUNTY AS
WINDS WILL BE FROM THE WEST TO NORTHWEST. WINDS/WAVES AND
ASSOCIATED HIGHER SWIM RISK SUBSIDES BY LATE AFTN WITH LOSS OF
PRESSURE RISES AND TIGHTER PRESSURE GRADIENT.
HIGH PRESSURE REMAINS MAIN WEATHER FEATURE FOR THU/FRI. TEMPS MAY
DROP INTO THE LOW-MID 40S OVER INTERIOR COOL SPOTS ON THURSDAY NIGHT
WITH LGT SOUTHERLY FLOW AS RIDGE AXIS DRIFTS ACROSS. AIRMASS DOES
NOT APPEAR TO BE NEARLY COLD OR DRY ENOUGH FOR ANY FROST POTENTIAL.
HIGH TEMPS BOTH DAYS SHOULD TOP OUT IN THE MID-UPR 70S AWAY FROM THE
GREAT LAKES. MAY EVEN SEE A FEW SPOTS BACK NEAR 80 DEGREES BY
THURSDAY.
UNCERTAINTY ABOUNDS WITH TIMING AND EXTENT OF NEXT ROUND AND/OR
ROUNDS OF SHRA/TSRA THIS WEEKEND INTO NEXT MONDAY. ECMWF NORMALLY
LEADS WAY IN TERMS OF VERIFICATION...BUT BOY ARE ITS SOLUTIONS IN
THE LAST COUPLE DAYS QUITE INCONSISTENT IN TERMS OF TIMING FOR THE
WEEKEND SHRA/TSRA CHANCES. DOES SEEM LIKE ECMWF IS TRENDING TOWARD
SLOWER IDEA SHOWN BY GFS FOR ARRIVAL OF PRECIP FRIDAY NIGHT. WILL
START TO SHOW TREND OF CHANCE POPS ONLY OVER THE FAR WEST LATE ON
FRIDAY NIGHT WHILE IT STAYS MAINLY DRY ELSEWHERE. UPPER HEIGHTS
FLATTEN OUT SATURDAY ALLOWING SHORTWAVES AND MID-LEVEL WIND MAX TO
SLIDE ACROSS UPPER GREAT LAKES REGION. MAIN SFC LOW WILL BE WELL TO
NORTH CLOSER TO SHARPER TROUGH ALOFT...BUT SW LOW-LEVEL FLOW ALONG
WITH INCREASING MOISTURE AND BUILDING INSTABILITY JUST UPSTREAM
SHOULD RESULT IN AT LEAST A CHANCE OF SHRA/TSRA AHEAD OF SFC-H85
TROUGH THAT MOVES THROUGH BY SUNDAY MORNING. WITH WRLY FLOW
ALOFT...FRONT MAY END UP STALLING OUT LATER IN THE WEEKEND PROVIDING
A FOCUS FOR ADDITIONAL SHRA/TSRA. FOR MOST PART USED CONSENSUS
POPS...BUT DID INCREASE POPS SLIGHTLY OVER THE SOUTH AND EAST CWA
CLOSER TO EXPECTED POSITION OF FRONT PER WPC HAND DRAWN SFC PROGS.
BASED ON GENERAL S/SW GRADIENT FLOW AHEAD OF FRONT AND H85 TEMPS IN
THE MID TEENS...INCREASED TEMPS OVER CONSENSUS GUIDANCE. EXPECT MAX
TEMPS FRIDAY THROUGH SUNDAY IN THE MID-UPR 70S TO AS WARM AS MID
80S. IT WILL ALL DEPEND ON EXTENT OF CLOUDS AND SHRA/TSRA. AFTER MIN
TEMPS IN THE 40S AND 50S MUCH OF THIS WEEK...READINGS RETURN TO THE
WARMER/MUGGIER 60S BY THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 116 PM EDT TUE JUL 9 2013
THE MAIN ISSUES DURING THIS TAF PERIOD WILL BE FOCUSED ON TS CHANCES
THIS AFTERNOON WITH MVFR TO IFR CONDITIONS DEVELOPING OVERNIGHT.
HAVE PLACED VCTS IN THE IWD TAF AT THE BEGINNING OF THE TAF PERIOD
WITH THUNDERSTORMS APPROACHING THE AREA FROM THE SOUTH. CURRENT
THINKING IS THAT THIS WILL BE THE MAIN AREA OF CONVECTION THIS
AFTERNOON...SHIFTING EASTWARD TO SAW BY 21Z. CMX MAY MISS OUT ON
MOST OF THE CONVECTION DUE TO LINGERING CLOUD COVER AND GREATER
STABILITY. CEILING AND VISIBILITY WILL LOWER THIS EVENING THROUGH
MUCH OF TONIGHT AHEAD OF THE APPROACHING COLD FRONT. IT WOULD NOT BE
OUT OF THE QUESTION FOR A FEW RUMBLES OF THUNDER NEAR THE IWD AND
SAW TAF SITE BEFORE FROPA...BUT DO NOT EXPECT WIDE SPREAD
THUNDERSTORM ACTIVITY. ONCE FRONT PASSES CEILINGS AND VISIBILITY
WILL IMPROVE TO VFR CONDITIONS NEAR DAY BREAK WEDNESDAY. WINDS MAY
BECOME A BIT GUST BEHIND THE COLD FRONT THROUGH THE DAY
WEDNESDAY...WITH GUSTS REACHING NEARLY 25 KNOTS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 359 PM EDT MON JUL 8 2013
DENSE FOG REMAINS A CONCERN ACROSS LAKE SUPERIOR THROUGH TUESDAY
MORNING. LIGHT WINDS AND LITTLE AIR MASS MOVEMENT WILL ALLOW FOR THE
REDEVELOPMENT OF AREAS OF DENSE FOG OVERNIGHT. CLEARING SKIES FOR
TUESDAY MORNING SHOULD ALLOW ENOUGH HEATING TO MIX OUT THE MOST
DENSE FOG BY TUESDAY AFTERNOON. PATCHY FOG WILL THEN LINGER INTO
WEDNESDAY BEFORE A COLD FRONT BRINGS DRIER AIR FROM WEST TO EAST
ACROSS THE LAKE. WINDS SHOULD BE LIGHT AND GENERALLY VARIABLE
THROUGH TUESDAY EVENING. THEN...EXPECT WINDS TO VEER TO THE NW AT 15
TO 25 KNOTS...MAINLY ACROSS THE EAST HALF OF THE LAKE...FOR LATE
TUESDAY NIGHT THROUGH WEDNESDAY. HIGH PRESSURE WILL THEN BUILD INTO
THE AREA THURSDAY THROUGH SATURDAY AND BRING LIGHT WINDS UNDER 15
KNOTS FOR MUCH OF THE TIME PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 5 PM EDT /4 PM CDT/ THIS AFTERNOON FOR
LSZ162-240>251-263>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...KEC
MARINE...KLUBER
AREA FORECAST DISCUSSION
NWS GAYLORD MI
106 PM EDT TUE JUL 9 2013
.SYNOPSIS...
ISSUED AT 344 AM EDT TUE JUL 9 2013
THERE WILL BE SMALL CHANCES FOR POP UP SHOWERS AND THUNDERSTORMS
TODAY. BETTER CHANCES OF RAINFALL WILL OCCUR TONIGHT INTO WEDNESDAY
MORNING AS A COLD FRONT APPROACHES THE REGION. HIGH PRESSURE WILL
BEGIN TO BUILD IN BY LATE WEDNESDAY...BRINGING COOLER AND LESS HUMID
CONDITIONS FOR MIDWEEK. A WARMING TREND WILL THEN FOLLOW FOR LATE IN
THE WEEK INTO THE UPCOMING WEEKEND.
&&
.UPDATE...
ISSUED AT 106 PM EDT TUE JUL 9 2013
WELL...HERE WE GO WITH MORE SURPRISES. UPSTREAM CONVECTION IS WELL
AHEAD OF SCHEDULE AND IS HOLDING TOGETHER NICELY. MUCAPE VALUES
ARE ON THE RISE ACROSS SOUTHWEST PARTS OF THE CWA WHERE SUNSHINE
IS BREAKING OUT AND A WARM FRONT IS SLOWLY LIFTING NORTH. BASED ON
LATEST HRRR DATA (WHICH IS ITSELF ABOUT 3 HOURS TOO SLOW WITH
CURRENT ACTIVITY)...WILL NEED TO PUSH UP ARRIVAL TIME OF PRECIP
CHANCES ROUGHLY 20-23C ACROSS THE CWA. WITH THAT SAID...AM A
LITTLE LEARY THAT ACTIVITY MAY TEND TO FADE WITH EASTERN EXTENT
GIVEN LACK OF INSTABILITY ACROSS NORTHEAST LOWER (LOTS OF
REMAINING STRATUS)...BUT THAT`S MORE OF A VERY NEAR TERM ISSUE AS
WE START LOOKING AT THE OVERNIGHT FORECAST. SEVERE POTENTIAL VERY
LOW AT THIS TIME.
UPDATE ISSUED AT 953 AM EDT TUE JUL 9 2013
INTERESTING AND CHALLENGING FORECAST THROUGH LATE AFTERNOON AND
EVENING (SOUNDS LIKE THE TYPICAL NORTHERN MICHIGAN TAGLINE DOESN`T
IT?)...WITH FORECAST ISSUES CENTERED MAINLY ON CLOUD/FOG/TEMP
TRENDS THROUGH MUCH OF THE DAY...BUT SHIFTING TOWARD CONVECTIVE
CHANCES BY LATE AFTERNOON AND EVENING. FIRST OF ALL...WILL JUST
COME RIGHT OUT AND SAY THAT THIS REMAINS A FAIRLY LOW CONFIDENCE
FORECAST WITH REGARD TO ANY CONVECTIVE EVOLUTION LATER
TODAY...WITH EVEN LOWER CONFIDENCE ABOUT ANY SEVERE POTENTIAL.
HOWEVER...STARTING TO GET THE FEELING CONVECTION MAY TRY TO SNEAK
INTO THE PICTURE A LITTLE EARLIER THAN CURRENTLY EXPECTED. MORE ON
THAT BELOW...BUT FIRST THINGS FIRST...WE WILL CONTINUE TO DEAL
WITH WIDESPREAD STRATUS AND GRADUALLY LIFTING FOG THROUGH AT LEAST
LATE MORNING...AND PROBABLY A LITTLE BEYOND. 12Z APX RAOB TELLS
THE STORY...WITH A GOOD DEAL OF MOISTURE SANDWICHED BELOW
900MB...AND IN PARTICULAR BELOW 950MB...COURTESY OF A SHALLOW
INVERSION AND PLENTIFUL BOUNDARY LAYER MOISTURE FROM YESTERDAY`S
MUCH-NEEDED RAINFALL. BASED ON PAST EXPERIENCE...THIS GRUNGE WILL
TAKE SOME TIME TO MIX OUT...AND WILL PROBABLY TRANSITION FROM PURE
STRATUS TO A THICKER STRATOCU DECK AROUND MIDDAY (WON`T TAKE MUCH
TO CONVECTIVELY SATURATE THE 900MB LEVEL PER SOUNDING)...BEFORE
ERODING TO SOME DEGREE AS DRIER AIR ABOVE 875 ATTEMPTS TO MIX IN.
HOWEVER...SATELLITE ANALYSIS ALREADY SHOWING PLENTY OF THICKER
DEBRIS CLOUDS MAKING INROADS THROUGH THE WESTERN LAKES...SO HAVE
TO BELIEVE THINGS WILL CLOUD BACK UP FAIRLY QUICKLY ACROSS THE
WESTERN CWA THROUGH MID AND LATE AFTERNOON. THIS MAKES TEMPS
TRICKY...AND IN GENERAL GUT FEELING SAYS TO LOWER AT LEAST A
COUPLE OF DEGREES...THOUGH WITH THE CAVEAT THAT IT DOESN`T TAKE
MUCH SUN TO SEND READINGS SOARING THIS TIME OF YEAR.
AS FOR PRECIP CHANCES...NOTHING DOING THROUGH AT LEAST 19-21Z...AS
STOUT CAPPING AROUND 750MB AND STUBBORNLY SLOW WARMING (AT LEAST
INITIALLY) WORK IN TANDEM...COUPLED WITH SUBTLE SHORTWAVE
RIDGING ALOFT/NO FORCING. HOWEVER...REALLY WATCHING UPSTREAM
CONVECTIVE ACTIVITY...TIED TO A LEADING SHORTWAVE TRAVERSING
WESTERN MINNESOTA...OUT AHEAD OF THE MAIN UPPER TROUGH AMPLIFYING
INTO THE NORTHERN PLAINS. PER RADAR TRENDS AND SHORT TERM GUIDANCE
HINTS...REALLY STARTING TO GET THE FEELING THAT SOME OF THIS
ACTIVITY SLIDING EAST FROM NORTHERN IOWA MAY TRY TO IMPACT PARTS
OF THE SOUTHERN CWA BY LATE AFTERNOON OR EARLY EVENING. ACTIVITY
IS CURRENTLY TRYING TO OUTRUN THE BETTER INSTABILITY...HOWEVER...
THIS WON`T BE THE CASE FOR LONG AS STRENGTHENING SOUTHERN FLOW
AHEAD OF THE WAVE IS PROGGED TO HELP LIFT A SUBTLE WARM FRONT BACK
NORTH INTO CENTRAL WISCONSIN AND EVENTUALLY PARTS OF NORTHERN
MICHIGAN. THERE ARE INCREASING HINTS OF BETTER POOLED MOISTURE
ALONG THIS BOUNDARY (SEE UPSTREAM DEW POINTS OVER THE SOUTHERN
LAKES IN THE LOW 70S)...WHICH COMBINED WITH AT LEAST A LITTLE
DAYTIME HEATING AND SUBTLE MID LEVEL HEIGHT FALLS MAY BE ENOUGH TO
SUSTAIN THE WARM ADVECTION WING COMPONENT OF THE CURRENT LARGER
UPSTREAM MCS.
LATEST HRRR GUIDANCE REALLY PICKING UP ON THIS IDEA AND GIVEN
CURRENT RADAR MOSAIC...KIND OF HARD TO ARGUE AT THE MOMENT. THIS
IS ESPECIALLY TRUE WITH FURTHER HINTS THAT A LOCALIZED LOW LEVEL
JET MAXIMUM MAY ALSO POKE INTO THE SOUTHWEST CWA OFF LAKE
MICHIGAN...COINCIDENT WITH THE ARRIVAL OF SOMEWHAT BETTER MID
LEVEL LAPSE RATES (STILL NOTHING STELLAR) AND BETTER LOW LEVEL
THETA-E RIDGING. HAVE RE-WORKED POPS TO SHOW THIS IDEA BETTER.
DON`T ANTICIPATE A BIG SEVERE THREAT THROUGH 00Z WITH RATHER SLACK
WIND FIELDS (DEEP SHEAR ONLY ABOUT 20 KNOTS) AND LIMITED
INSTABILITY (MIXED LAYER CAPE UP AROUND 700 J/KG).
UPDATE ISSUED AT 629 AM EDT TUE JUL 9 2013
DENSE FOG HAS EXPANDED OVER THE LAST HOUR OR SO..AND AN SPS HAS
BEEN ISSUED FOR LESS THAN A QUARTER OF A MILE VISIBILITIES. THE
WORST OF VISIBILITY REDUCTION WAS FOCUSED IN THE COASTAL
COMMUNITIES SURROUNDING LAKES MICHIGAN AND HURON. TEMPERATURES
WILL BE AT A STAND-STILL FOR THE NEXT SEVERAL HOURS...AS THE
STRATUS WILL GO NOWHERE FOR MOST OF THE MORNING. THERE HAVE BEEN
NO RAIN SHOWERS FOR THE LAST SEVERAL HOURS...AND NEWER DATA COMING
IN...IF ANYTHING...SUGGEST MAYBE EVEN A STRONGER CAP TO PREVENT
AFTERNOON SHOWERS AND STORMS. WILL PLAY IT SAFE HERE THOUGH AND
KEEP SLIGHT CHANCES IN THE FORECAST...FOR THE MERE FACT THAT WE
WILL HAVE DEVELOPED LAKE BREEZES AND A PIECE OF SHORTWAVE ENERGY
THAT COULD POSSIBLY OVERCOME CAPPING...ALTHOUGH IT DOESN`T LOOK
LIKE IT. BELIEVE THERE WILL BE AFTERNOON SUN...EVENTUALLY FOR
TEMPERATURES TO MAKE IT INTO THE 80S....BUT WILL DROP EXPECTED
HIGHS A COUPLE DEGREES.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 344 AM EDT TUE JUL 9 2013
CURRENTLY...WEAK LOW PRESSURE WAS WORKING EASTWARD ACROSS NE
LOWER...WITH SHOWER ACTIVITY VANISHING AFTER LOSS OF HEATING.
MOISTURE HAS BEEN STRIPPED OUT ALOFT AND THE BL REMAINS MOIST.
RADIATIONAL COOLING ON TOP OF THIS BL MOISTURE HAS RESULTED IN
WIDESPREAD STRATUS...AS FAR OUT AS WISCONSIN. THIS STRATUS WAS ALSO
UNDERNEATH A DEVELOPING CAP DUE TO SUBSIDENCE AND SFC HIGH PRESSURE
BETWEEN DEPARTING LOW...AND UPSTREAM NEXT LOW PRESSURE AND COLD
FRONT. THIS LOW WAS IN FAR NW ONTARIO...WITH ITS COLD FRONT DRAPED
DOWN THROUGH NORTH DAKOTA. THERE WAS RELATIVE DRY AIR AND NO PRECIP
YESTERDAY WITHIN THE HIGH PRESSURE.TEMPERATURES IN THE STRATUS HAS
FLAT-LINED...IN THE UPPER 60S FOR MOST.
TODAY...NEW DATA INDICATING THE BL MOISTURE IS QUITE MOIST AND THICK
ENOUGH FOR THE SOLID STRATUS TO CONTINUE WELL INTO THE MORNING. WILL
KEEP SKIES CLOUDY ALL MORNING...BEFORE HEATING CAN FINALLY RESULT IN
HOLES AND A PRETTY GOOD COVERAGE OF CUMULUS. THERE SEEMS TO BE QUITE
THE CHANGE IN EXPECTATIONS FOR PRECIPITATION DEVELOPMENT FOR THIS
AFTERNOON. A CAP DEVELOPS AT 750MB...VERIFIED BY 00Z UPSTREAM
SOUNDINGS ACROSS MINNEAPOLIS/GREEN BAY. USING A PARCEL OF 88/67 WILL
RESULT IN ROUGHLY 1400 J/KG SBCAPE AND ONLY A FEW HUNDRED J/KG
MLCAPE (WHICH MAY BE BETTER CONSIDERING THE DRYNESS OF THE ENTIRE
BL). THUS...CHANCES FOR SEEING ANY SORT OF DIURNAL SHOWERS AND
THUNDERSTORMS HAVE DRASTICALLY DWINDLED DUE TO A SIGNIFICANT AMOUNT
OF CAPPING/WARM AIR ALOFT. WILL JUST KEEP A 20 PERCENT CHANCE FOR
THE LATE AFTERNOON AND EVENING. HIGHS SHOULD MAKE A LATER DAY RUN AT
THE MIDDLE AND UPPER 80S.
TONIGHT...AFTER ANY DIURNAL CONVECTION WANES...WE WILL BE AWAITING
THE MAIN SHOW. THE FAR NRN ONTARIO LOW PRESSURE MOVES EAST AND THE
TRAILING COLD FRONT WILL BE MARCHING FROM FAR WESTERN WISCONSIN AND
INTO/NEAR EASTERN UPPER/LAKE MICHIGAN BY 12Z. STRONGER SHORTWAVE
ENERGY AND NICE UPPER DIVERGENCE SIGNAL WILL WORK IN CONCERT WITH
LOW LEVEL CONVERGENCE ASSOCIATED WITH THE FRONT...TO FIRE OFF
SHOWERS AND STORMS FOR THE OVERNIGHT. THESE STORMS WILL HAVE BEEN
GENERATED ACROSS WISCONSIN IN THE AFTERNOON...BUT EVEN WITH LOSS OF
HEATING...THE UPPER FORCING OUGHT TO SUSTAIN THUNDER. MUCAPES ARE
PRETTY MINIMAL...IN THE FEW HUNDREDS OR SO...AND WILL DOWNPLAY THE
AMOUNT OF THUNDER WITH THE RAIN SHOWERS. THE BETTER/DEEPER
INSTABILITY WILL BE WELL SOUTH OF US...IN HIGHER THETA-E AIR ACROSS
NRN IL/INDIANA. THE CONVECTION THERE MAY ALSO SERVE TO ROB US OF
SOME MOISTURE...ALTHOUGH PWATS ARE EXPECTED TO BE HIGH...1.80" TO
ALMOST 2.00" LIQUID. STRATUS AND FOG WILL ALSO BE A CONCERN IN JUICY
AIR MASS...BEFORE DRYING SETS IN ON WEDNESDAY. LOWS IN THE MID/UPPER
60S.
&&
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 344 AM EDT TUE JUL 9 2013
AN UPPER LEVEL TROUGH IN PLACE WEDNESDAY INTO THURSDAY WILL LIFT OUT
OF THE REGION AS A LARGE UPPER LEVEL RIDGE CENTERED ACROSS THE
DESERT SOUTHWEST EXPANDS NORTHEAST INTO THE GREAT LAKES REGION
THURSDAY NIGHT INTO THE WEEKEND. ANOTHER TROUGH MOVING BY TO THE
NORTH WILL THEN BEAT DOWN THIS RIDGE EARLY NEXT WEEK. THIS SCENARIO
WILL RESULT IN COOLER TEMPERATURES FOR MIDWEEK FOLLOWED BY A WARMING
TREND FOR FRIDAY INTO THIS WEEKEND. MEANWHILE...THERE WILL BE MORE
CHANCES OF SHOWERS AND THUNDERSTORMS WEDNESDAY...FOLLOWED BY
PRECIPITATION FREE WEATHER INTO THE WEEKEND. THERE WILL BE SMALL
CHANCES FOR A FEW SHOWERS OR STORMS EARLY NEXT WEEK AS THE TROUGH
MOVES BY. THE MAIN LONG TERM FOCUS IS ON LINGERING POPS WEDNESDAY
THEN POPS AGAIN NEXT MONDAY.
WEDNESDAY...THE SURFACE COLD FRONT CONTINUES TO ADVANCE ACROSS THE
REGION FROM NORTHWEST TO SOUTHEAST WITH DRIER AIR ADVECTING IN
BEHIND IT. IN ADVANCE OF THE FRONT...THE NAM INDICATES 1000-1500
J/KG OF ML CAPE FROM GAYLORD SE TO GLADWIN THROUGH EARLY AFTERNOON.
HOWEVER...THE NAM IS THE MOISTEST MODEL BY FAR WITH THE GFS ET ALL
INDICATING LOTS OF DRY AIR ADVECTION (MEAN 1000-500 MB RH FALLING TO
ABOUT 40 PERCENT OR SO). THEREFORE WILL LEAVE POPS IN THE CHANCE
CATEGORY. POTENTIAL FOR SEVERE STORMS APPEARS LIMITED WITH LIGHT
WIND FIELDS ALOFT. HIGHS RANGING FROM AROUND 70 FAR NORTH TO THE
LOWER 80S SOUTHEAST.
THURSDAY THROUGH MONDAY...THE CORE OF THE UPPER LEVEL COOL POOL IS
OVERHEAD (850 MB TEMPS OF PLUS 8 TO 10 C) BUT FAIRLY DRY AIR (MEAN
1000-500 MB RH 30 TO 40 PERCENT) SHOULD INHIBIT DAYTIME HEATING
DRIVEN SHOWERS FROM FORMING. OTHERWISE...EXTENDED MODELS CONTINUE TO
BE IN GOOD AGREEMENT WITH RIDGING AT THE SURFACE AND SLOWLY BUILDING
HEIGHTS ALOFT LEADING TO ANOTHER PLEASANT AND INCREASINGLY WARM
STRETCH OF WEATHER INTO THE WEEKEND. AN UPPER LEVEL TROUGH AND
ASSOCIATED WEAK COLD FRONT WILL THEN BRING SMALL CHANCES FOR SHOWERS
OR THUNDERSTORMS EARLY NEXT WEEK. HIGHS THURSDAY IN THE MIDDLE TO
UPPER 70S...FRIDAY IN THE MIDDLE 70S TO LOWER 80S...WITH THE UPPER
70S TO MIDDLE 80S FOR SATURDAY THROUGH MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 106 PM EDT TUE JUL 9 2013
A VARIETY OF CONDITIONS WILL CONTINUE ACROSS THE TAF SITES THROUGH
LATE AFTERNOON...WITH THE WORST OF THEM AROUND KAPN WHERE IFR
STRATUS WILL GRADUALLY LIFT TO MVFR. WILL BE WATCHING A LINE OF
SHOWERS AND STORMS TRYING TO CROSS THE LAKE INTO LATE
AFTERNOON...AND SUSPECT THIS FEATURE HAS A GOOD CHANCE OF
SURVIVAL...SO HAVE PUSHED UP ARRIVAL TIME BY MANY HOURS...THOUGH
WITH PREDOMINANTLY VFR CONDITIONS EXPECTED (OUTSIDE OF SOME LOCAL
IFR FOR A FEW MINUTES IN HEAVY RAIN). NOT SURE IF WE WILL BE ABLE
TO KICK OFF ANYTHING ELSE OVERNIGHT AS A COLD FRONT
APPROACHES...BUT STARTING TO HAVE MY DOUBTS...SO WILL REMOVE ALL
PRECIP BY 03-06Z AT THE LATEST. INSTEAD...REMAINING MOIST AIRMASS
SHOULD GO INTO MORE FOG/STRATUS PRODUCTION...WITH THE EXPECTATION
OF MANY SITES ENDING UP IFR ONCE AGAIN. WINDS WILL BE LIGHT
THROUGH MUCH OF THE NIGHT...BUT SHIFT TO THE WEST AND BECOME GUSTY
UP TO 25 KNOTS ON WEDNESDAY.
&&
.MARINE...
ISSUED AT 344 AM EDT TUE JUL 9 2013
WINDS WILL CONTINUE TO BE VARIABLE AND LIGHT THROUGH TONIGHT UNDER
STABLE CONDITIONS ON THE LAKES. UPSTREAM COLD FRONT WILL APPROACH
OVERNIGHT AND INTO WEDNESDAY FOR SHOWERS AND STORMS...AND BEHIND THE
FRONT WINDS WILL SHIFT TO OUT OF THE NW. MAYBE HAVE SOME ADVISORY
LEVEL GUSTS AT PRESQUE ISLE...SSM/ST MARYS. WINDS WILL LIGHTEN UP
OVER TIME THEN...AS HIGH PRESSURE GRADUALLY WORKS IN OVER NRN
MICHIGAN LATE THIS WORK WEEK...AND THE WEEKEND.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...LAWRENCE
SYNOPSIS...AS
SHORT TERM...SD
LONG TERM...AS
AVIATION...LAWRENCE
MARINE...SD
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1236 PM EDT TUE JUL 9 2013
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 335 AM EDT TUE JUL 9 2013
MOST OF THE DAY TODAY SHOULD SEE A GOOD DEAL OF SUNSHINE AND VERY
WARM AND HUMID TEMPERATURES AFTER MORNING LOW CLOUDS AND FOG
DISSIPATE. THERE WILL BE A SLIGHT CHANCE OF A STORM DURING THE
AFTERNOON HOURS. THE BETTER CHANCE OF MORE WIDESPREAD SHOWERS AND
STORMS WILL COME TOWARD AND AFTER MIDNIGHT TONIGHT AS A WAVE OF LOW
PRESSURE MOVES THROUGH THE AREA.
THE CHANCE OF RAIN WILL DIMINISH THROUGH THE DAY ON WEDNESDAY AS A
COLD FRONT PUSHES SOUTH THROUGH THE AREA. TEMPERATURES WILL BE A BIT
COOLER WEDNESDAY AFTERNOON. EVEN COOLER TEMPERATURES AND DRY
CONDITIONS WILL BE FOUND FOR THE REMAINDER OF THE WEEK BEFORE WE
START TO WARM UP AGAIN THIS COMING WEEKEND.
&&
.UPDATE...
ISSUED AT 1236 PM EDT TUE JUL 9 2013
I HAVE UPDATED OUR GRIDS TO SPEED UP THE TIMING ON THE CONVECTION
ASSOCIATED WITH THE MAIN UPPER WAVE COMING THROUGH THE CWA TO THE
6 PM TO 10 PM TIME FRAME. THIS IS BASED ON TIMING THE WATER VAPOR
IMAGE LOOPS...THE TIMING ON THE 12Z NAM...GFS...RAP AND THE HRRR
AS FAR OUT AS IT GOES. BASED ON THE WATER VAPOR IMAGE LOOPS THE
BACK EDGE GETS TO THE LAKE SHORE BY 8 PM AND THE
JACKSON...LANSING...ALAMA AREA BY 10 PM. THIS SUGGESTS THE STORM
THREAT WILL BE LARGELY OVER BY 10 PM SO I HAVE LIKELY POPS DURING
6 PM TO 10 PM TIME FRAME BUT HAVE ONLY CHANCE POPS AFTER THAT THROUGH
8 AM WEDNESDAY. IF CURRENT TRENDS CONTINUE I WOULD LOWER THE POPS
AFTER MIDNIGHT TO BELOW 20 PERCENT.
THE LIFT IN THE DGZ ON THE RAP MODEL CONTINUES TO BE THE BEST
FEATURE THAT CORRELATES TO THE LOCATION OF THE LIGHTING TODAY.
THAT BRINGS THE MAIN LINE OF STORMS THROUGH THE CWA FROM 8 PM
(WEST CWA) TILL 10 PM (EAST CWA). HOWEVER THERE IS THE SUGGESTION
THERE COULD BE A FEW STORMS DEVELOPING ON THE WARM FRONT...WEST OF
JXN ALONG INTERSTATE 94 BY 4 PM. THOSE STORMS SHOULD HEAD
NORTHEAST TOWARD LANSING BY 5 TO 6 PM.
MODEL SOUNDING MLCAPES ARE FORECAST TO BE IN THE 1500 TO 3000
J/KG RANGE BUT THE DEEP LAYER SHEAR AHEAD OF THE FRONT IS UNDER 25
KNOTS SO I DO NOT EXPECT AN ORGANIZED SEVERE STORM OUTBREAK WITH
THIS....JUST SOME ISOLATED WIND DAMAGE REPORTS. WITH THE FREEZING
LEVEL NEAR 15,500 FT AND THE -20 NEAR 26,000 FT... HAIL WOULD BE
LESS OF A THREAT BUT THERE IS A FAIR AMOUNT OF CAPE IN THE -10 TO
-20C LAYER SO I CAN NOT TOTALLY RULE IT OUT.
WITH THE FASTER MOVEMENT OF THE SYSTEM TEMPERATURES MAY NOT GET TO
90 DEGREES AFTER ALL SINCE THE CLOUDS WILL BE MOVING IN SHORTLY
(BASED ON VISIBLE AND IR LOOPS). STILL WE SHOULD SEE MID TO UPPER
80S INLAND WITH NO PROBLEM.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 335 AM EDT TUE JUL 9 2013
THE MAIN ISSUE IN THE SHORT TERM IS FOG THIS MORNING...THEN STORM
POTENTIAL AND SEVERE THREAT FOR LATE TODAY AND TONIGHT.
A FAIR AMOUNT OF FOG AND LOW CLOUDS HAVE DEVELOPED OVER THE NRN
SECTION OF THE CWFA EARLY THIS MORNING. SOME OF THIS IS STARTING TO
DEVELOP FURTHER SOUTH AS A WEAK SFC TROUGH CRAWLING SOUTH ACROSS THE
AREA IS LIKELY BEING OVERRUN A BIT JUST OFF THE SFC AND WITH THE
HUMID AIR MASS IN PLACE. WE DO EXPECT THAT THIS WILL DISSIPATE
DURING THE MID MORNING HOURS AS THE STRONG SUN ANGLE WORKS ON THE
SHALLOW LAYER OF MOISTURE.
WE EXPECT TO SEE A GOOD DEAL OF SUNSHINE AFTER THE LOW CLOUDS AND
FOG DISSIPATE. THE AREA WILL BE UNDER THE INFLUENCE OF SHORT WAVE
RIDGING ALOFT BETWEEN THE DEPARTING WAVE FROM YESTERDAY AND THE NEXT
WAVE EXPECTED TONIGHT. FCST SOUNDINGS SHOW A WARM LAYER BETWEEN
850-700MB THAT SHOULD CAP MOST IF NOT ALL CONVECTIVE DEVELOPMENT
THROUGH ALMOST 00Z. WE CAN NOT RULE OUT AN ISOLATED SHOWER/STORM
DEVELOPING ALONG A BOUNDARY LIKE A LAKE BREEZE. THAT SAID...THE LOW
LEVEL FLOW LOOKS FAIRLY DIVERGENT DURING THE DAY TODAY WHICH SHOULD
LIMIT ANY DEVELOPMENT ALSO.
THE AREA STILL LOOKS LIKE IT IS ON TRACK FOR A BATCH OF SHOWERS AND
STORMS TO MOVE THROUGH TONIGHT. THE BEST CHANCE WILL OCCUR ALONG AND
SOUTH OF INTERSTATE 96. OUR FOCUS IS ON THE SHORT WAVE PRODUCING
CONVECTION ACROSS THE DAKOTAS...AND THE EVENTUAL LLJ THAT IS
EXPECTED TO DEVELOP THIS EVENING/OVERNIGHT.
WE DO EXPECT THE SHORT WAVE TO MOVE INTO THE AREA TOWARD 06Z. IT
SEEMS THAT THE CONVECTION ACROSS THE DAKOTAS SHOULD SLOWLY MOVE
THROUGH THE DAY. WE COULD SEE IT INTENSIFY A BIT IN WISCONSIN THIS
AFTERNOON AS IT ENCOUNTERS BUILDING INSTABILITY THERE. THIS LINE
WILL LIKELY DIMINISH SOME AS IT HEADS TOWARD OUR CWFA TONIGHT WITH
THE LOSS OF DIURNAL INSTABILITY.
WHAT WE WILL SEE IS THE LLJ INCREASE A BIT AND THE NOSE BE AIMED AT
THE SRN HALF OF THE CWFA BY 06Z. THIS SHOULD HELP MAINTAIN A FAIRLY
DECENT AREA OF SHOWERS AND STORMS THAT WOULD LAST INTO THE DAYBREAK
HOURS ON WED BEFORE MOVING OUT. SEVERE THREAT DOES NOT SEEM VERY
IMPRESSIVE DUE TO THE LATE NIGHT TIME FRAME THE CONVECTION WOULD BE
MOVING IN. FCST SOUNDINGS INDICATE THAT THE CAPE IN THE -10 TO -30C
LAYER IS NOT REAL ABUNDANT. DEEP LAYER CLOUD LAYER SHEAR IS ON THE
LOWER SIDE AROUND 20-25 KNOTS OR SO. MOST OF THE STORMS WOULD BE
ELEVATED WITH SOME POSSIBILITY OF SOME WINDS MAKING IT DOWN WITH
SOME RESIDUAL LOW LEVEL INSTABILITY.
WE FEEL THAT IF THE STORMS MOVE THROUGH AS EXPECTED TONIGHT...MOST
OF THE CWFA WILL BE WORKED OVER ENOUGH FOR WED THAT THE THREAT OF
STORMS AND SEVERE WEATHER IS LOW. IT WILL TAKE A WHILE TO BUILD UP
THE INSTABILITY...AND THE FRONT SHOULD CLEAR THE CWFA BY PEAK
HEATING. THE BEST CHC FOR STORMS WILL BE DOWN SOUTH WHERE LOCATIONS
DO NOT SEE MCS ACTIVITY TONIGHT.
WE WILL SEE SKIES CLEAR THEN WED EVENING AND CONTINUE THROUGH THU AS
DRIER AND COOLER AIR MOVES IN. A SHORT WAVE DOES MOVE THROUGH FROM
THE NW ON THU...HOWEVER THE AIR SHOULD BE DRY ENOUGH AND WE WILL BE
ON THE DOWNSTREAM SIDE OF THE LONG WAVE RIDGE TO OUR WEST TO KEEP US
DRY.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 335 AM EDT TUE JUL 9 2013
THE ARRIVAL OF MID LEVEL RIDGING EARLY IN THE PERIOD SUPPORTS A DRY
PATTERN FOR THE REGION THEN. SUBSIDENCE IS SEEN ON BUFKIT OVERVIEWS
AND MOISTURE PROFILES REMAIN DRY THROUGH SAT. A WARM AIR ADVECTION
PATTERN SETS UP BY SUNDAY AND PWAT VALUES WILL BE ON THE INCREASE.
A WEAKENING SURFACE FRONT SLIPS DOWN FROM THE NORTHWEST SUNDAY NIGHT
INTO MONDAY. WITH SOME ELEVATED/SURFACE INSTABILITY ALONG OR AHEAD
OF THE FRONTAL ZONE...THERE COULD BE A FEW STORMS.
THE BELOW NORMAL TEMPERATURES TO START THE PERIOD TRANSITION TO
ABOVE NORMAL VALUES FOR THE END OF THE PERIOD. TEMPERATURE VALUES
AT 925 MB CLIMB INTO THE LOW TO MID 20 DEG C RANGE SUNDAY. WITH
SOME SUN...WE SHOULD EASILY REACH THE MID 80S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 739 AM EDT TUE JUL 9 2013
LOW CLOUDS WILL BE SLOW DO DISSIPATE ESPECIALLY CLOSER TO THE
LAKESHORE THIS MORNING. IMPACTS TO PERSIST WITH IFR/LIFR COMMON TO
START. BY 16Z CONDITIONS AT MOST SITES SHOULD BE MVFR.
LINE OF STORMS TRACKING THROUGH NRN IOWA WILL ARRIVE IN WRN MI
AFTER 19Z IF THEY SURVIVE. UNSTABLE CONDITIONS PERSIST MUCH OF THE
NIGHT. SO TAFS WILL FEATURE THE POSSIBILITY OF A STORM THROUGH THE EVENING.
&&
.MARINE...
ISSUED AT 335 AM EDT TUE JUL 9 2013
NO HEADLINES WILL BE ISSUED WITH THIS FCST PACKAGE...HOWEVER WE ARE
LOOKING AT FOG POTENTIAL THROUGH TONIGHT...ROUGH WEATHER TONIGHT
WITH A POSSIBLE ROUND OF STORMS...AND THEN SOME DECENT WINDS
POSSIBLE WED BEHIND THE FRONT.
THE LIGHT GRADIENT OVER THE LAKE THIS MORNING ALONG WITH THE HUMID
AIR MASS OVER THE SOMEWHAT COOL WATER IS LIKELY PRODUCING SOME FOG.
WEBCAMS SHOW SOME PLACES SEEING FOG WHILE OTHERS ARE NOT. WE DO NOT
FEEL CONFIDENT ENOUGH AT THIS TIME TO ISSUE A MARINE FOG ADVISORY...
HOWEVER IT IS SOMETHING WE WILL NEED TO MONITOR.
WINDS AHEAD OF THE WAVE MOVING IN TONIGHT WILL HAVE THE POTENTIAL TO
INCREASE THE WINDS AND WAVES SOME TONIGHT. THE BIGGER THREAT WILL
LIKELY BE THE STORMS THAT ARE ANTICIPATED. THE BEST WIND WILL COME
WITH ANY STORMS. A DECENT NW WIND COULD DEVELOP LATE WED AFTERNOON
BEHIND THE FRONT THAT PUSHES THROUGH. A SMALL CRAFT ADVISORY MAY BE
NEEDED FOR THAT PERIOD.
&&
.HYDROLOGY...
ISSUED AT 335 AM EDT TUE JUL 9 2013
THE MAIN PERIOD OF CONCERN AS FAR AS HYDRO IS CONCERNED IS THE
TONIGHT PERIOD. WE WILL SEE PRECIPITABLE WATER INCREASE TO AROUND
2.00 INCHES THIS EVENING AHEAD OF THE WAVE THAT WILL MOVE THROUGH
THE AREA. THIS WILL PROVIDE THE POTENTIAL OF HEAVY DOWNPOURS ACROSS
THE AREA. WE DO NOT ANTICIPATE SIGNIFICANT WIDESPREAD ISSUES AS THIS
WAVE THAT MOVES THROUGH SHOULD BE RATHER PROGRESSIVE. AMOUNTS WILL
LIKELY BE A QUARTER TO THREE QUARTERS OF AN INCH OF RAINFALL FOR
BASIN AVERAGES...WITH SOME LOCAL AREAS SEEING 1-2 INCHES OF RAIN.
URBAN AND SMALL STREAM ISSUES WILL BE THE MAIN THREAT.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...MJS
AVIATION...MJS
HYDROLOGY...NJJ
MARINE...NJJ
AREA FORECAST DISCUSSION
NWS GAYLORD MI
953 AM EDT TUE JUL 9 2013
.SYNOPSIS...
ISSUED AT 344 AM EDT TUE JUL 9 2013
THERE WILL BE SMALL CHANCES FOR POP UP SHOWERS AND THUNDERSTORMS
TODAY. BETTER CHANCES OF RAINFALL WILL OCCUR TONIGHT INTO WEDNESDAY
MORNING AS A COLD FRONT APPROACHES THE REGION. HIGH PRESSURE WILL
BEGIN TO BUILD IN BY LATE WEDNESDAY...BRINGING COOLER AND LESS HUMID
CONDITIONS FOR MIDWEEK. A WARMING TREND WILL THEN FOLLOW FOR LATE IN
THE WEEK INTO THE UPCOMING WEEKEND.
&&
.UPDATE...
ISSUED AT 953 AM EDT TUE JUL 9 2013
INTERESTING AND CHALLENGING FORECAST THROUGH LATE AFTERNOON AND
EVENING (SOUNDS LIKE THE TYPICAL NORTHERN MICHIGAN TAGLINE DOESN`T
IT?)...WITH FORECAST ISSUES CENTERED MAINLY ON CLOUD/FOG/TEMP
TRENDS THROUGH MUCH OF THE DAY...BUT SHIFTING TOWARD CONVECTIVE
CHANCES BY LATE AFTERNOON AND EVENING. FIRST OF ALL...WILL JUST
COME RIGHT OUT AND SAY THAT THIS REMAINS A FAIRLY LOW CONFIDENCE
FORECAST WITH REGARD TO ANY CONVECTIVE EVOLUTION LATER
TODAY...WITH EVEN LOWER CONFIDENCE ABOUT ANY SEVERE POTENTIAL.
HOWEVER...STARTING TO GET THE FEELING CONVECTION MAY TRY TO SNEAK
INTO THE PICTURE A LITTLE EARLIER THAN CURRENTLY EXPECTED. MORE ON
THAT BELOW...BUT FIRST THINGS FIRST...WE WILL CONTINUE TO DEAL
WITH WIDESPREAD STRATUS AND GRADUALLY LIFTING FOG THROUGH AT LEAST
LATE MORNING...AND PROBABLY A LITTLE BEYOND. 12Z APX RAOB TELLS
THE STORY...WITH A GOOD DEAL OF MOISTURE SANDWICHED BELOW
900MB...AND IN PARTICULAR BELOW 950MB...COURTESY OF A SHALLOW
INVERSION AND PLENTIFUL BOUNDARY LAYER MOISTURE FROM YESTERDAY`S
MUCH-NEEDED RAINFALL. BASED ON PAST EXPERIENCE...THIS GRUNGE WILL
TAKE SOME TIME TO MIX OUT...AND WILL PROBABLY TRANSITION FROM PURE
STRATUS TO A THICKER STRATOCU DECK AROUND MIDDAY (WON`T TAKE MUCH
TO CONVECTIVELY SATURATE THE 900MB LEVEL PER SOUNDING)...BEFORE
ERODING TO SOME DEGREE AS DRIER AIR ABOVE 875 ATTEMPTS TO MIX IN.
HOWEVER...SATELLITE ANALYSIS ALREADY SHOWING PLENTY OF THICKER
DEBRIS CLOUDS MAKING INROADS THROUGH THE WESTERN LAKES...SO HAVE
TO BELIEVE THINGS WILL CLOUD BACK UP FAIRLY QUICKLY ACROSS THE
WESTERN CWA THROUGH MID AND LATE AFTERNOON. THIS MAKES TEMPS
TRICKY...AND IN GENERAL GUT FEELING SAYS TO LOWER AT LEAST A
COUPLE OF DEGREES...THOUGH WITH THE CAVEAT THAT IT DOESN`T TAKE
MUCH SUN TO SEND READINGS SOARING THIS TIME OF YEAR.
AS FOR PRECIP CHANCES...NOTHING DOING THROUGH AT LEAST 19-21Z...AS
STOUT CAPPING AROUND 750MB AND STUBBORNLY SLOW WARMING (AT LEAST
INITIALLY) WORK IN TANDEM...COUPLED WITH SUBTLE SHORTWAVE
RIDGING ALOFT/NO FORCING. HOWEVER...REALLY WATCHING UPSTREAM
CONVECTIVE ACTIVITY...TIED TO A LEADING SHORTWAVE TRAVERSING
WESTERN MINNESOTA...OUT AHEAD OF THE MAIN UPPER TROUGH AMPLIFYING
INTO THE NORTHERN PLAINS. PER RADAR TRENDS AND SHORT TERM GUIDANCE
HINTS...REALLY STARTING TO GET THE FEELING THAT SOME OF THIS
ACTIVITY SLIDING EAST FROM NORTHERN IOWA MAY TRY TO IMPACT PARTS
OF THE SOUTHERN CWA BY LATE AFTERNOON OR EARLY EVENING. ACTIVITY
IS CURRENTLY TRYING TO OUTRUN THE BETTER INSTABILITY...HOWEVER...
THIS WON`T BE THE CASE FOR LONG AS STRENGTHENING SOUTHERN FLOW
AHEAD OF THE WAVE IS PROGGED TO HELP LIFT A SUBTLE WARM FRONT BACK
NORTH INTO CENTRAL WISCONSIN AND EVENTUALLY PARTS OF NORTHERN
MICHIGAN. THERE ARE INCREASING HINTS OF BETTER POOLED MOISTURE
ALONG THIS BOUNDARY (SEE UPSTREAM DEW POINTS OVER THE SOUTHERN
LAKES IN THE LOW 70S)...WHICH COMBINED WITH AT LEAST A LITTLE
DAYTIME HEATING AND SUBTLE MID LEVEL HEIGHT FALLS MAY BE ENOUGH TO
SUSTAIN THE WARM ADVECTION WING COMPONENT OF THE CURRENT LARGER
UPSTREAM MCS.
LATEST HRRR GUIDANCE REALLY PICKING UP ON THIS IDEA AND GIVEN
CURRENT RADAR MOSAIC...KIND OF HARD TO ARGUE AT THE MOMENT. THIS
IS ESPECIALLY TRUE WITH FURTHER HINTS THAT A LOCALIZED LOW LEVEL
JET MAXIMUM MAY ALSO POKE INTO THE SOUTHWEST CWA OFF LAKE
MICHIGAN...COINCIDENT WITH THE ARRIVAL OF SOMEWHAT BETTER MID
LEVEL LAPSE RATES (STILL NOTHING STELLAR) AND BETTER LOW LEVEL
THETA-E RIDGING. HAVE RE-WORKED POPS TO SHOW THIS IDEA BETTER.
DON`T ANTICIPATE A BIG SEVERE THREAT THROUGH 00Z WITH RATHER SLACK
WIND FIELDS (DEEP SHEAR ONLY ABOUT 20 KNOTS) AND LIMITED
INSTABILITY (MIXED LAYER CAPE UP AROUND 700 J/KG).
UPDATE ISSUED AT 629 AM EDT TUE JUL 9 2013
DENSE FOG HAS EXPANDED OVER THE LAST HOUR OR SO..AND AN SPS HAS
BEEN ISSUED FOR LESS THAN A QUARTER OF A MILE VISIBILITIES. THE
WORST OF VISIBILITY REDUCTION WAS FOCUSED IN THE COASTAL
COMMUNITIES SURROUNDING LAKES MICHIGAN AND HURON. TEMPERATURES
WILL BE AT A STAND-STILL FOR THE NEXT SEVERAL HOURS...AS THE
STRATUS WILL GO NOWHERE FOR MOST OF THE MORNING. THERE HAVE BEEN
NO RAIN SHOWERS FOR THE LAST SEVERAL HOURS...AND NEWER DATA COMING
IN...IF ANYTHING...SUGGEST MAYBE EVEN A STRONGER CAP TO PREVENT
AFTERNOON SHOWERS AND STORMS. WILL PLAY IT SAFE HERE THOUGH AND
KEEP SLIGHT CHANCES IN THE FORECAST...FOR THE MERE FACT THAT WE
WILL HAVE DEVELOPED LAKE BREEZES AND A PIECE OF SHORTWAVE ENERGY
THAT COULD POSSIBLY OVERCOME CAPPING...ALTHOUGH IT DOESN`T LOOK
LIKE IT. BELIEVE THERE WILL BE AFTERNOON SUN...EVENTUALLY FOR
TEMPERATURES TO MAKE IT INTO THE 80S....BUT WILL DROP EXPECTED
HIGHS A COUPLE DEGREES.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 344 AM EDT TUE JUL 9 2013
CURRENTLY...WEAK LOW PRESSURE WAS WORKING EASTWARD ACROSS NE
LOWER...WITH SHOWER ACTIVITY VANISHING AFTER LOSS OF HEATING.
MOISTURE HAS BEEN STRIPPED OUT ALOFT AND THE BL REMAINS MOIST.
RADIATIONAL COOLING ON TOP OF THIS BL MOISTURE HAS RESULTED IN
WIDESPREAD STRATUS...AS FAR OUT AS WISCONSIN. THIS STRATUS WAS ALSO
UNDERNEATH A DEVELOPING CAP DUE TO SUBSIDENCE AND SFC HIGH PRESSURE
BETWEEN DEPARTING LOW...AND UPSTREAM NEXT LOW PRESSURE AND COLD
FRONT. THIS LOW WAS IN FAR NW ONTARIO...WITH ITS COLD FRONT DRAPED
DOWN THROUGH NORTH DAKOTA. THERE WAS RELATIVE DRY AIR AND NO PRECIP
YESTERDAY WITHIN THE HIGH PRESSURE.TEMPERATURES IN THE STRATUS HAS
FLAT-LINED...IN THE UPPER 60S FOR MOST.
TODAY...NEW DATA INDICATING THE BL MOISTURE IS QUITE MOIST AND THICK
ENOUGH FOR THE SOLID STRATUS TO CONTINUE WELL INTO THE MORNING. WILL
KEEP SKIES CLOUDY ALL MORNING...BEFORE HEATING CAN FINALLY RESULT IN
HOLES AND A PRETTY GOOD COVERAGE OF CUMULUS. THERE SEEMS TO BE QUITE
THE CHANGE IN EXPECTATIONS FOR PRECIPITATION DEVELOPMENT FOR THIS
AFTERNOON. A CAP DEVELOPS AT 750MB...VERIFIED BY 00Z UPSTREAM
SOUNDINGS ACROSS MINNEAPOLIS/GREEN BAY. USING A PARCEL OF 88/67 WILL
RESULT IN ROUGHLY 1400 J/KG SBCAPE AND ONLY A FEW HUNDRED J/KG
MLCAPE (WHICH MAY BE BETTER CONSIDERING THE DRYNESS OF THE ENTIRE
BL). THUS...CHANCES FOR SEEING ANY SORT OF DIURNAL SHOWERS AND
THUNDERSTORMS HAVE DRASTICALLY DWINDLED DUE TO A SIGNIFICANT AMOUNT
OF CAPPING/WARM AIR ALOFT. WILL JUST KEEP A 20 PERCENT CHANCE FOR
THE LATE AFTERNOON AND EVENING. HIGHS SHOULD MAKE A LATER DAY RUN AT
THE MIDDLE AND UPPER 80S.
TONIGHT...AFTER ANY DIURNAL CONVECTION WANES...WE WILL BE AWAITING
THE MAIN SHOW. THE FAR NRN ONTARIO LOW PRESSURE MOVES EAST AND THE
TRAILING COLD FRONT WILL BE MARCHING FROM FAR WESTERN WISCONSIN AND
INTO/NEAR EASTERN UPPER/LAKE MICHIGAN BY 12Z. STRONGER SHORTWAVE
ENERGY AND NICE UPPER DIVERGENCE SIGNAL WILL WORK IN CONCERT WITH
LOW LEVEL CONVERGENCE ASSOCIATED WITH THE FRONT...TO FIRE OFF
SHOWERS AND STORMS FOR THE OVERNIGHT. THESE STORMS WILL HAVE BEEN
GENERATED ACROSS WISCONSIN IN THE AFTERNOON...BUT EVEN WITH LOSS OF
HEATING...THE UPPER FORCING OUGHT TO SUSTAIN THUNDER. MUCAPES ARE
PRETTY MINIMAL...IN THE FEW HUNDREDS OR SO...AND WILL DOWNPLAY THE
AMOUNT OF THUNDER WITH THE RAIN SHOWERS. THE BETTER/DEEPER
INSTABILITY WILL BE WELL SOUTH OF US...IN HIGHER THETA-E AIR ACROSS
NRN IL/INDIANA. THE CONVECTION THERE MAY ALSO SERVE TO ROB US OF
SOME MOISTURE...ALTHOUGH PWATS ARE EXPECTED TO BE HIGH...1.80" TO
ALMOST 2.00" LIQUID. STRATUS AND FOG WILL ALSO BE A CONCERN IN JUICY
AIR MASS...BEFORE DRYING SETS IN ON WEDNESDAY. LOWS IN THE MID/UPPER
60S.
&&
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 344 AM EDT TUE JUL 9 2013
AN UPPER LEVEL TROUGH IN PLACE WEDNESDAY INTO THURSDAY WILL LIFT OUT
OF THE REGION AS A LARGE UPPER LEVEL RIDGE CENTERED ACROSS THE
DESERT SOUTHWEST EXPANDS NORTHEAST INTO THE GREAT LAKES REGION
THURSDAY NIGHT INTO THE WEEKEND. ANOTHER TROUGH MOVING BY TO THE
NORTH WILL THEN BEAT DOWN THIS RIDGE EARLY NEXT WEEK. THIS SCENARIO
WILL RESULT IN COOLER TEMPERATURES FOR MIDWEEK FOLLOWED BY A WARMING
TREND FOR FRIDAY INTO THIS WEEKEND. MEANWHILE...THERE WILL BE MORE
CHANCES OF SHOWERS AND THUNDERSTORMS WEDNESDAY...FOLLOWED BY
PRECIPITATION FREE WEATHER INTO THE WEEKEND. THERE WILL BE SMALL
CHANCES FOR A FEW SHOWERS OR STORMS EARLY NEXT WEEK AS THE TROUGH
MOVES BY. THE MAIN LONG TERM FOCUS IS ON LINGERING POPS WEDNESDAY
THEN POPS AGAIN NEXT MONDAY.
WEDNESDAY...THE SURFACE COLD FRONT CONTINUES TO ADVANCE ACROSS THE
REGION FROM NORTHWEST TO SOUTHEAST WITH DRIER AIR ADVECTING IN
BEHIND IT. IN ADVANCE OF THE FRONT...THE NAM INDICATES 1000-1500
J/KG OF ML CAPE FROM GAYLORD SE TO GLADWIN THROUGH EARLY AFTERNOON.
HOWEVER...THE NAM IS THE MOISTEST MODEL BY FAR WITH THE GFS ET ALL
INDICATING LOTS OF DRY AIR ADVECTION (MEAN 1000-500 MB RH FALLING TO
ABOUT 40 PERCENT OR SO). THEREFORE WILL LEAVE POPS IN THE CHANCE
CATEGORY. POTENTIAL FOR SEVERE STORMS APPEARS LIMITED WITH LIGHT
WIND FIELDS ALOFT. HIGHS RANGING FROM AROUND 70 FAR NORTH TO THE
LOWER 80S SOUTHEAST.
THURSDAY THROUGH MONDAY...THE CORE OF THE UPPER LEVEL COOL POOL IS
OVERHEAD (850 MB TEMPS OF PLUS 8 TO 10 C) BUT FAIRLY DRY AIR (MEAN
1000-500 MB RH 30 TO 40 PERCENT) SHOULD INHIBIT DAYTIME HEATING
DRIVEN SHOWERS FROM FORMING. OTHERWISE...EXTENDED MODELS CONTINUE TO
BE IN GOOD AGREEMENT WITH RIDGING AT THE SURFACE AND SLOWLY BUILDING
HEIGHTS ALOFT LEADING TO ANOTHER PLEASANT AND INCREASINGLY WARM
STRETCH OF WEATHER INTO THE WEEKEND. AN UPPER LEVEL TROUGH AND
ASSOCIATED WEAK COLD FRONT WILL THEN BRING SMALL CHANCES FOR SHOWERS
OR THUNDERSTORMS EARLY NEXT WEEK. HIGHS THURSDAY IN THE MIDDLE TO
UPPER 70S...FRIDAY IN THE MIDDLE 70S TO LOWER 80S...WITH THE UPPER
70S TO MIDDLE 80S FOR SATURDAY THROUGH MONDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 629 AM EDT TUE JUL 9 2013
IFR CONDITIONS ARE GOING TO CONTINUE THROUGH MUCH OF THE MORNING
AS STRATUS AND FOG WILL BE VERY STUBBORN TO LIFT. BL MOISTURE IS
FAIRLY SUBSTANTIAL AND HEATING THROUGH IT TO HELP CLEAR SKIES OUT
WILL BE MINIMAL FOR AWHILE. DO BELIEVE VFR CONDITIONS WILL DEVELOP
LATER THIS AFTERNOON...BUT CHANCES FOR SEEING SHOWERS AND STORMS
IN THE AFTERNOON AND EVENING ARE QUITE SMALL...AS WARM AIR ALOFT
HAS CAPPED THINGS OFF QUITE WELL. NEWER DATA ROLLING IN FURTHER
SUGGEST THINGS WILL BE QUIET. HOWEVER...THE MAIN SHOW WILL STILL
BE LATER TONIGHT...LIGHT WINDS EARLY AND THE DEVELOPMENT OF LIGHT
FOG IN PERHAPS A PERIOD OF CLEARING...WILL TURN ACTIVE. AN
UPSTREAM LOW PRESSURE AND COLD FRONT WILL ARRIVE IN EASTERN UPPER
AND LAKE MICHIGAN BY 12Z. SHOWERS AND STORMS OUT AHEAD OF THIS
FRONT WILL ROLL THROUGH NW LOWER AROUND 06Z...AND APN AROUND 09Z.
THERE IS A SLIGHT CHANCE THAT TVC/MBL COULD SEE A SEVERE
STORM...BUT DO BELIEVE THAT THIS IS A VERY SMALL CHANCE.
&&
.MARINE...
ISSUED AT 344 AM EDT TUE JUL 9 2013
WINDS WILL CONTINUE TO BE VARIABLE AND LIGHT THROUGH TONIGHT UNDER
STABLE CONDITIONS ON THE LAKES. UPSTREAM COLD FRONT WILL APPROACH
OVERNIGHT AND INTO WEDNESDAY FOR SHOWERS AND STORMS...AND BEHIND THE
FRONT WINDS WILL SHIFT TO OUT OF THE NW. MAYBE HAVE SOME ADVISORY
LEVEL GUSTS AT PRESQUE ISLE...SSM/ST MARYS. WINDS WILL LIGHTEN UP
OVER TIME THEN...AS HIGH PRESSURE GRADUALLY WORKS IN OVER NRN
MICHIGAN LATE THIS WORK WEEK...AND THE WEEKEND.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...LAWRENCE
SYNOPSIS...AS
SHORT TERM...SD
LONG TERM...AS
AVIATION...SD
MARINE...SD
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
845 AM EDT TUE JUL 9 2013
LATEST UPDATE...
MESOSCALE DISCUSSION
.MESOSCALE DISCUSSION...
ISSUED AT 844 AM EDT TUE JUL 9 2013
CURRENTLY (830 AM) THERE ARE TWO LINES OF THUNDERSTORMS HEADED
TOWARD SOUTHWEST LOWER MICHIGAN. IF THE LINE CONTINUED TO PROGRESS
AS IT IS... IT WOULD REACH HOLLAND AROUND 2 PM THIS AFTERNOON.
HOWEVER LOOKING AT RAP MODEL SOUNDINGS WE STILL HAVE A SIGNIFICANT
DRY LAYER FROM 6000 FT TO 15000 FT THAT WOULD HAVE TO BE
OVERCOME. ALSO THE AREA OF SATURATED LIFT IN THE DGZ ON THE RAP
MODEL NEARLY PERFECTLY MATCHES THE LIGHTING ACTIVITY OVER THE
PAST 4 HOURS... AND THAT AREA DOES NOT REACH SOUTHWEST LOWER
MICHIGAN THROUGH 5 PM. ACTUALLY THE NORTHERN AREA HEADS TOWARD THE
UPPER PENINSULA AND THE SOUTHERN AREA HEADS TOWARD CHI AND MKE.
ALSO THE LOW LEVEL JET WEAKENS AS IT COMES TOWARD SOUTHWEST LOWER
MICHIGAN. BOTH THE HRRR AND RAP MODEL DO NOT BRING THE
THUNDERSTORMS INTO OUR CWA THROUGH 5 PM. THE HRR TAKES THE
SOUTHERN AREA INTO BERRIEN COUNTY AROUND 6 PM. ONE OTHER ASPECT TO
THIS IS THE DEEP LAYER SHEAR IS UNDER 20 KNOTS THROUGH 8 PM OVER
ALL OF THE SOUTHERN 2/3 OF LOWER MICHIGAN SO THAT WILL HELP TO
KEEP THE STORMS FROM GETTING TO ORGANIZED.
SO MY SPIN ON THIS IS THAT LINE... IF IT GETS HERE WILL BE RATHER
WEAK AND DISSIPATING DUE TO THE CAP CREATED BY THE DEEP DRY LAYER.
THERE COULD BE SOME STRONG STORMS OVER OUR EXTREME SOUTHWEST
COUNTIES TOWARD DINNER TIME.
&&
.SYNOPSIS...
ISSUED AT 335 AM EDT TUE JUL 9 2013
MOST OF THE DAY TODAY SHOULD SEE A GOOD DEAL OF SUNSHINE AND VERY
WARM AND HUMID TEMPERATURES AFTER MORNING LOW CLOUDS AND FOG
DISSIPATE. THERE WILL BE A SLIGHT CHANCE OF A STORM DURING THE
AFTERNOON HOURS. THE BETTER CHANCE OF MORE WIDESPREAD SHOWERS AND
STORMS WILL COME TOWARD AND AFTER MIDNIGHT TONIGHT AS A WAVE OF LOW
PRESSURE MOVES THROUGH THE AREA.
THE CHANCE OF RAIN WILL DIMINISH THROUGH THE DAY ON WEDNESDAY AS A
COLD FRONT PUSHES SOUTH THROUGH THE AREA. TEMPERATURES WILL BE A BIT
COOLER WEDNESDAY AFTERNOON. EVEN COOLER TEMPERATURES AND DRY
CONDITIONS WILL BE FOUND FOR THE REMAINDER OF THE WEEK BEFORE WE
START TO WARM UP AGAIN THIS COMING WEEKEND.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 335 AM EDT TUE JUL 9 2013
THE MAIN ISSUE IN THE SHORT TERM IS FOG THIS MORNING...THEN STORM
POTENTIAL AND SEVERE THREAT FOR LATE TODAY AND TONIGHT.
A FAIR AMOUNT OF FOG AND LOW CLOUDS HAVE DEVELOPED OVER THE NRN
SECTION OF THE CWFA EARLY THIS MORNING. SOME OF THIS IS STARTING TO
DEVELOP FURTHER SOUTH AS A WEAK SFC TROUGH CRAWLING SOUTH ACROSS THE
AREA IS LIKELY BEING OVERRUN A BIT JUST OFF THE SFC AND WITH THE
HUMID AIR MASS IN PLACE. WE DO EXPECT THAT THIS WILL DISSIPATE
DURING THE MID MORNING HOURS AS THE STRONG SUN ANGLE WORKS ON THE
SHALLOW LAYER OF MOISTURE.
WE EXPECT TO SEE A GOOD DEAL OF SUNSHINE AFTER THE LOW CLOUDS AND
FOG DISSIPATE. THE AREA WILL BE UNDER THE INFLUENCE OF SHORT WAVE
RIDGING ALOFT BETWEEN THE DEPARTING WAVE FROM YESTERDAY AND THE NEXT
WAVE EXPECTED TONIGHT. FCST SOUNDINGS SHOW A WARM LAYER BETWEEN
850-700MB THAT SHOULD CAP MOST IF NOT ALL CONVECTIVE DEVELOPMENT
THROUGH ALMOST 00Z. WE CAN NOT RULE OUT AN ISOLATED SHOWER/STORM
DEVELOPING ALONG A BOUNDARY LIKE A LAKE BREEZE. THAT SAID...THE LOW
LEVEL FLOW LOOKS FAIRLY DIVERGENT DURING THE DAY TODAY WHICH SHOULD
LIMIT ANY DEVELOPMENT ALSO.
THE AREA STILL LOOKS LIKE IT IS ON TRACK FOR A BATCH OF SHOWERS AND
STORMS TO MOVE THROUGH TONIGHT. THE BEST CHANCE WILL OCCUR ALONG AND
SOUTH OF INTERSTATE 96. OUR FOCUS IS ON THE SHORT WAVE PRODUCING
CONVECTION ACROSS THE DAKOTAS...AND THE EVENTUAL LLJ THAT IS
EXPECTED TO DEVELOP THIS EVENING/OVERNIGHT.
WE DO EXPECT THE SHORT WAVE TO MOVE INTO THE AREA TOWARD 06Z. IT
SEEMS THAT THE CONVECTION ACROSS THE DAKOTAS SHOULD SLOWLY MOVE
THROUGH THE DAY. WE COULD SEE IT INTENSIFY A BIT IN WISCONSIN THIS
AFTERNOON AS IT ENCOUNTERS BUILDING INSTABILITY THERE. THIS LINE
WILL LIKELY DIMINISH SOME AS IT HEADS TOWARD OUR CWFA TONIGHT WITH
THE LOSS OF DIURNAL INSTABILITY.
WHAT WE WILL SEE IS THE LLJ INCREASE A BIT AND THE NOSE BE AIMED AT
THE SRN HALF OF THE CWFA BY 06Z. THIS SHOULD HELP MAINTAIN A FAIRLY
DECENT AREA OF SHOWERS AND STORMS THAT WOULD LAST INTO THE DAYBREAK
HOURS ON WED BEFORE MOVING OUT. SEVERE THREAT DOES NOT SEEM VERY
IMPRESSIVE DUE TO THE LATE NIGHT TIME FRAME THE CONVECTION WOULD BE
MOVING IN. FCST SOUNDINGS INDICATE THAT THE CAPE IN THE -10 TO -30C
LAYER IS NOT REAL ABUNDANT. DEEP LAYER CLOUD LAYER SHEAR IS ON THE
LOWER SIDE AROUND 20-25 KNOTS OR SO. MOST OF THE STORMS WOULD BE
ELEVATED WITH SOME POSSIBILITY OF SOME WINDS MAKING IT DOWN WITH
SOME RESIDUAL LOW LEVEL INSTABILITY.
WE FEEL THAT IF THE STORMS MOVE THROUGH AS EXPECTED TONIGHT...MOST
OF THE CWFA WILL BE WORKED OVER ENOUGH FOR WED THAT THE THREAT OF
STORMS AND SEVERE WEATHER IS LOW. IT WILL TAKE A WHILE TO BUILD UP
THE INSTABILITY...AND THE FRONT SHOULD CLEAR THE CWFA BY PEAK
HEATING. THE BEST CHC FOR STORMS WILL BE DOWN SOUTH WHERE LOCATIONS
DO NOT SEE MCS ACTIVITY TONIGHT.
WE WILL SEE SKIES CLEAR THEN WED EVENING AND CONTINUE THROUGH THU AS
DRIER AND COOLER AIR MOVES IN. A SHORT WAVE DOES MOVE THROUGH FROM
THE NW ON THU...HOWEVER THE AIR SHOULD BE DRY ENOUGH AND WE WILL BE
ON THE DOWNSTREAM SIDE OF THE LONG WAVE RIDGE TO OUR WEST TO KEEP US
DRY.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 335 AM EDT TUE JUL 9 2013
THE ARRIVAL OF MID LEVEL RIDGING EARLY IN THE PERIOD SUPPORTS A DRY
PATTERN FOR THE REGION THEN. SUBSIDENCE IS SEEN ON BUFKIT OVERVIEWS
AND MOISTURE PROFILES REMAIN DRY THROUGH SAT. A WARM AIR ADVECTION
PATTERN SETS UP BY SUNDAY AND PWAT VALUES WILL BE ON THE INCREASE.
A WEAKENING SURFACE FRONT SLIPS DOWN FROM THE NORTHWEST SUNDAY NIGHT
INTO MONDAY. WITH SOME ELEVATED/SURFACE INSTABILITY ALONG OR AHEAD
OF THE FRONTAL ZONE...THERE COULD BE A FEW STORMS.
THE BELOW NORMAL TEMPERATURES TO START THE PERIOD TRANSITION TO
ABOVE NORMAL VALUES FOR THE END OF THE PERIOD. TEMPERATURE VALUES
AT 925 MB CLIMB INTO THE LOW TO MID 20 DEG C RANGE SUNDAY. WITH
SOME SUN...WE SHOULD EASILY REACH THE MID 80S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 739 AM EDT TUE JUL 9 2013
LOW CLOUDS WILL BE SLOW DO DISSIPATE ESPECIALLY CLOSER TO THE
LAKESHORE THIS MORNING. IMPACTS TO PERSIST WITH IFR/LIFR COMMON TO
START. BY 16Z CONDITIONS AT MOST SITES SHOULD BE MVFR.
LINE OF STORMS TRACKING THROUGH NRN IOWA WILL ARRIVE IN WRN MI
AFTER 19Z IF THEY SURVIVE. UNSTABLE CONDITIONS PERSIST MUCH OF THE
NIGHT. SO TAFS WILL FEATURE THE POSSIBILITY OF A STORM THROUGH THE EVENING.
&&
.MARINE...
ISSUED AT 335 AM EDT TUE JUL 9 2013
NO HEADLINES WILL BE ISSUED WITH THIS FCST PACKAGE...HOWEVER WE ARE
LOOKING AT FOG POTENTIAL THROUGH TONIGHT...ROUGH WEATHER TONIGHT
WITH A POSSIBLE ROUND OF STORMS...AND THEN SOME DECENT WINDS
POSSIBLE WED BEHIND THE FRONT.
THE LIGHT GRADIENT OVER THE LAKE THIS MORNING ALONG WITH THE HUMID
AIR MASS OVER THE SOMEWHAT COOL WATER IS LIKELY PRODUCING SOME FOG.
WEBCAMS SHOW SOME PLACES SEEING FOG WHILE OTHERS ARE NOT. WE DO NOT
FEEL CONFIDENT ENOUGH AT THIS TIME TO ISSUE A MARINE FOG ADVISORY...
HOWEVER IT IS SOMETHING WE WILL NEED TO MONITOR.
WINDS AHEAD OF THE WAVE MOVING IN TONIGHT WILL HAVE THE POTENTIAL TO
INCREASE THE WINDS AND WAVES SOME TONIGHT. THE BIGGER THREAT WILL
LIKELY BE THE STORMS THAT ARE ANTICIPATED. THE BEST WIND WILL COME
WITH ANY STORMS. A DECENT NW WIND COULD DEVELOP LATE WED AFTERNOON
BEHIND THE FRONT THAT PUSHES THROUGH. A SMALL CRAFT ADVISORY MAY BE
NEEDED FOR THAT PERIOD.
&&
.HYDROLOGY...
ISSUED AT 335 AM EDT TUE JUL 9 2013
THE MAIN PERIOD OF CONCERN AS FAR AS HYDRO IS CONCERNED IS THE
TONIGHT PERIOD. WE WILL SEE PRECIPITABLE WATER INCREASE TO AROUND
2.00 INCHES THIS EVENING AHEAD OF THE WAVE THAT WILL MOVE THROUGH
THE AREA. THIS WILL PROVIDE THE POTENTIAL OF HEAVY DOWNPOURS ACROSS
THE AREA. WE DO NOT ANTICIPATE SIGNIFICANT WIDESPREAD ISSUES AS THIS
WAVE THAT MOVES THROUGH SHOULD BE RATHER PROGRESSIVE. AMOUNTS WILL
LIKELY BE A QUARTER TO THREE QUARTERS OF AN INCH OF RAINFALL FOR
BASIN AVERAGES...WITH SOME LOCAL AREAS SEEING 1-2 INCHES OF RAIN.
URBAN AND SMALL STREAM ISSUES WILL BE THE MAIN THREAT.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
MESOSCALE...WDM
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...MJS
AVIATION...MJS
HYDROLOGY...NJJ
MARINE...NJJ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
733 AM EDT TUE JUL 9 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 525 AM EDT TUE JUL 9 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A MAINLY ZONAL PATTERN ACROSS
THE NRN CONUS WITH SEVERAL UPSTREAM SHORTWAVE TROUGHS. THE MOST
PROMINENT SHRTWV WAS LOCATED OVER ERN MT WHILE A WEAKER IMPULSE AND
ASSOCIATED MCS WAS MOVING THROUGH ERN SD. AT THE SFC...A WEAK
FRONTAL BOUNDARY LINGERED ACROSS SRN WI WHILE A STRONGER COLD FRONT
AHEAD OF THE MT SHRTWV EXTENDED FROM NW ONTARIO INTO NRN ND. A WEAK
RIDGE EXTENDED FROM QUEBEC ACROSS LAKE SUPERIOR RESULTING IN
LIGHT/CALM WINDS OVERNIGHT. AREAS OF FOG...LOCALLY DENSE...HAS
DEVELOPED AS ABUNDANT LOW LEVEL MOISTURE LINGERED BELOW AN INVERSION
ABOVE 850 MB.
EXPECT THAT THE MORNING WILL BE DOMINATED BY LOW CLOUDS BUT WITH
DAYTIME HEATING/MIXING THE LOW CLOUDS ACROSS MOST OF THE AREA WILL
THIN OUT ENOUGH BY THIS AFTERNOON FOR TEMPERATURES TO CLIMB INTO THE
LOWER 80S INLAND. SATELLITE TRENDS...SHORTER TERM MODELS AND CAPE
GRADIENT...SUGGEST THAT THE ERN SD MCS WILL TRACK TO THE EAST INTO W
AND SRN WI.
THERE IS SOME UNCERTAINTY REGARDING THE IMPACTS OF THE MCS ON
CONVECTION DEVELOPING FARTHER TO THE NORTH. THE FORCING ASSOCIATED
WITH THE APPROACHING NRN PLAINS SHRTWV WITH 100M HEIGHT FALLS AND
MODERATE 700-300 QVECTOR CONV WILL ALSO BE STRONGEST TO THE NORTH OF
THE CWA. HOWEVER...THE SRN END OF THE SHRTWV SHOULD STILL BE STRONG
ENOUGH TO SUPPORT SCT SHRA/TSRA MOVING FROM NW WI INTO WRN UPPER MI
THIS AFTERNOON AND THROUGH THE REST OF THE CWA THIS EVENING.
EXPECTED MAX TEMPS AND DEWPOINTS INTO THE MID TO UPPER 60S GIVE CAPE
VALUES INTO THE 1K-2K J/KG RANGE...GREATEST WEST CENTRAL. 0-6KM BULK
SHEAR VALUES IN THE 30-35 KNOT RANGE WILL BE MARGINAL FOR STRONG/SVR
ORGANIZED CONVECTION BUT WITH TSRA MOVING THROUGH DURING PEAK
HEATING GIVING DCAPE VALUES IN THE 500-1000 J/KG RANGE...SOME
ISOLATED STRONG/DAMAGING WIND GUSTS MAY BE POSSIBLE WITH ANY
STRONGER STORMS. THE HIGHER PROBABILITIES FOR SVR STORMS REMAINS TO
THE SOUTH WHERE THE INSTABILITY IS GREATEST...PER SPC DAY1 OUTLOOK.
THE SHRA/TSRA ARE EXPECTED TO PROGRESS THROUGH THE AREA MOVING INTO
THE ERN CWA LATE THIS EVENING AND ENDING OVERNIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 525 AM EDT TUE JUL 9 2013
AFTER A FEW DAYS OF WARM AND ACTIVE WEATHER WITH POCKETS OF HEAVY
RAIN OVER MAINLY WESTERN HALF OF CWA...DEVELOPING TROUGHING ALOFT
ACROSS THE GREAT LAKES AND SFC HIGH ON THE WESTERN EDGE OF THE
TROUGH ALOFT WILL BRING QUIET AND COOLER WEATHER MID TO LATE WEEK.
WARMER TEMPERATURES AND INCREASING SHRA/TSRA CHANCES RETURN FOR THE
WEEKEND AS UPPER HEIGHTS BECOME MORE ZONAL.
OVERALL AGREEMENT THAT BEST CHANCE OF SHRA/TSRA ON WEDNESDAY WILL
BE 12-15Z OVER THE FAR EASTERN CWA. STRONGER TSRA STILL POSSIBLE
WITH MUCAPE UP TO 800J/KG. BETTER SHOT FOR SVR WILL BE FARTHER
SOUTH OVER SOUTHERN WI/NORTHERN IL CLOSER TO WEST-EAST FRONTAL
BOUNDARY AND ON NORTHERN GRADIENT OF HIGHER MLCAPES OVR 1000J/KG.
ANY CHANCES OF SHRA/TSRA OVER EAST QUICKLY END THROUGH MORNING AS
STRONG DEEP LAYER Q-VECTOR DIVERGENCE/SUBSIDENCE SURGES ACROSS
UPPER GREAT LAKES. PRESSURE GRADIENT BRIEFLY BECOMES TIGHT BTWN
THE EXITING LOW PRESSURE TROUGH AND HIGH PRESSURE BUILDING OVER
THE PLAINS. EXPECT BRIEF BUILDING WAVES AND INCREASED SWIM RISK
FOR WEDNESDAY OVER THE LK SUPERIOR BEACHES OF ALGER COUNTY AS
WINDS WILL BE FROM THE WEST TO NORTHWEST. WINDS/WAVES AND
ASSOCIATED HIGHER SWIM RISK SUBSIDES BY LATE AFTN WITH LOSS OF
PRESSURE RISES AND TIGHTER PRESSURE GRADIENT.
HIGH PRESSURE REMAINS MAIN WEATHER FEATURE FOR THU/FRI. TEMPS MAY
DROP INTO THE LOW-MID 40S OVER INTERIOR COOL SPOTS ON THURSDAY NIGHT
WITH LGT SOUTHERLY FLOW AS RIDGE AXIS DRIFTS ACROSS. AIRMASS DOES
NOT APPEAR TO BE NEARLY COLD OR DRY ENOUGH FOR ANY FROST POTENTIAL.
HIGH TEMPS BOTH DAYS SHOULD TOP OUT IN THE MID-UPR 70S AWAY FROM THE
GREAT LAKES. MAY EVEN SEE A FEW SPOTS BACK NEAR 80 DEGREES BY
THURSDAY.
UNCERTAINTY ABOUNDS WITH TIMING AND EXTENT OF NEXT ROUND AND/OR
ROUNDS OF SHRA/TSRA THIS WEEKEND INTO NEXT MONDAY. ECMWF NORMALLY
LEADS WAY IN TERMS OF VERIFICATION...BUT BOY ARE ITS SOLUTIONS IN
THE LAST COUPLE DAYS QUITE INCONSISTENT IN TERMS OF TIMING FOR THE
WEEKEND SHRA/TSRA CHANCES. DOES SEEM LIKE ECMWF IS TRENDING TOWARD
SLOWER IDEA SHOWN BY GFS FOR ARRIVAL OF PRECIP FRIDAY NIGHT. WILL
START TO SHOW TREND OF CHANCE POPS ONLY OVER THE FAR WEST LATE ON
FRIDAY NIGHT WHILE IT STAYS MAINLY DRY ELSEWHERE. UPPER HEIGHTS
FLATTEN OUT SATURDAY ALLOWING SHORTWAVES AND MID-LEVEL WIND MAX TO
SLIDE ACROSS UPPER GREAT LAKES REGION. MAIN SFC LOW WILL BE WELL TO
NORTH CLOSER TO SHARPER TROUGH ALOFT...BUT SW LOW-LEVEL FLOW ALONG
WITH INCREASING MOISTURE AND BUILDING INSTABILITY JUST UPSTREAM
SHOULD RESULT IN AT LEAST A CHANCE OF SHRA/TSRA AHEAD OF SFC-H85
TROUGH THAT MOVES THROUGH BY SUNDAY MORNING. WITH WRLY FLOW
ALOFT...FRONT MAY END UP STALLING OUT LATER IN THE WEEKEND PROVIDING
A FOCUS FOR ADDITIONAL SHRA/TSRA. FOR MOST PART USED CONSENSUS
POPS...BUT DID INCREASE POPS SLIGHTLY OVER THE SOUTH AND EAST CWA
CLOSER TO EXPECTED POSITION OF FRONT PER WPC HAND DRAWN SFC PROGS.
BASED ON GENERAL S/SW GRADIENT FLOW AHEAD OF FRONT AND H85 TEMPS IN
THE MID TEENS...INCREASED TEMPS OVER CONSENSUS GUIDANCE. EXPECT MAX
TEMPS FRIDAY THROUGH SUNDAY IN THE MID-UPR 70S TO AS WARM AS MID
80S. IT WILL ALL DEPEND ON EXTENT OF CLOUDS AND SHRA/TSRA. AFTER MIN
TEMPS IN THE 40S AND 50S MUCH OF THIS WEEK...READINGS RETURN TO THE
WARMER/MUGGIER 60S BY THE WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 733 AM EDT TUE JUL 9 2013
EXPECT DENSE FOG/VLIFR CONDITIONS TO IMPACT CMX/SAW EARLY TODAY MRNG
WITH LGT WINDS/HUMID LLVLS UNDER SFC HIGH PRES/DRIER AIR ALOFT.
DIURNAL HEATING SHOULD ALLOW A GRADUAL RETURN OF VFR WX.
SOME SHRA/TS IN ADVANCE OF A SHORTWAVE AND COLD FRONT WILL ARRIVE OVER
THE WRN IWD/CMX BY LATE AFTERNOON AND THEN MOVE E TOWARD SAW DURING
THE EVENING. ALTHOUGH THE RELATIVE DRYNESS OF THE LOW LEVELS SHOULD
ALLOW PREDOMINANT VFR CONDITIONS...POORER CONDITIONS WILL BE POSSIBLE
UNDER THE HEAVIER SHRA/TS. UPSLOPE WNW FLOW OFF LAKE SUPERIOR IN THE WAKE
OF THE CONVECTION MIGHT CAUSE PREDOMINANT MVFR WX AT
CMX...ESPECIALLY IF HEAVIER RA FALLS NEARBY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 359 PM EDT MON JUL 8 2013
DENSE FOG REMAINS A CONCERN ACROSS LAKE SUPERIOR THROUGH TUESDAY
MORNING. LIGHT WINDS AND LITTLE AIR MASS MOVEMENT WILL ALLOW FOR THE
REDEVELOPMENT OF AREAS OF DENSE FOG OVERNIGHT. CLEARING SKIES FOR
TUESDAY MORNING SHOULD ALLOW ENOUGH HEATING TO MIX OUT THE MOST
DENSE FOG BY TUESDAY AFTERNOON. PATCHY FOG WILL THEN LINGER INTO
WEDNESDAY BEFORE A COLD FRONT BRINGS DRIER AIR FROM WEST TO EAST
ACROSS THE LAKE. WINDS SHOULD BE LIGHT AND GENERALLY VARIABLE
THROUGH TUESDAY EVENING. THEN...EXPECT WINDS TO VEER TO THE NW AT 15
TO 25 KNOTS...MAINLY ACROSS THE EAST HALF OF THE LAKE...FOR LATE
TUESDAY NIGHT THROUGH WEDNESDAY. HIGH PRESSURE WILL THEN BUILD INTO
THE AREA THURSDAY THROUGH SATURDAY AND BRING LIGHT WINDS UNDER 15
KNOTS FOR MUCH OF THE TIME PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 5 PM EDT /4 PM CDT/ THIS AFTERNOON FOR
LSZ162-240>251-263>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...
MARINE...KLUBER
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
526 AM EDT TUE JUL 9 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 525 AM EDT TUE JUL 9 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A MAINLY ZONAL PATTERN ACROSS
THE NRN CONUS WITH SEVERAL UPSTREAM SHORTWAVE TROUGHS. THE MOST
PROMINENT SHRTWV WAS LOCATED OVER ERN MT WHILE A WEAKER IMPULSE AND
ASSOCIATED MCS WAS MOVING THROUGH ERN SD. AT THE SFC...A WEAK
FRONTAL BOUNDARY LINGERED ACROSS SRN WI WHILE A STRONGER COLD FRONT
AHEAD OF THE MT SHRTWV EXTENDED FROM NW ONTARIO INTO NRN ND. A WEAK
RIDGE EXTENDED FROM QUEBEC ACROSS LAKE SUPERIOR RESULTING IN
LIGHT/CALM WINDS OVERNIGHT. AREAS OF FOG...LOCALLY DENSE...HAS
DEVELOPED AS ABUNDANT LOW LEVEL MOISTURE LINGERED BELOW AN INVERSION
ABOVE 850 MB.
EXPECT THAT THE MORNING WILL BE DOMINATED BY LOW CLOUDS BUT WITH
DAYTIME HEATING/MIXING THE LOW CLOUDS ACROSS MOST OF THE AREA WILL
THIN OUT ENOUGH BY THIS AFTERNOON FOR TEMPERATURES TO CLIMB INTO THE
LOWER 80S INLAND. SATELLITE TRENDS...SHORTER TERM MODELS AND CAPE
GRADIENT...SUGGEST THAT THE ERN SD MCS WILL TRACK TO THE EAST INTO W
AND SRN WI.
THERE IS SOME UNCERTAINTY REGARDING THE IMPACTS OF THE MCS ON
CONVECTION DEVELOPING FARTHER TO THE NORTH. THE FORCING ASSOCIATED
WITH THE APPROACHING NRN PLAINS SHRTWV WITH 100M HEIGHT FALLS AND
MODERATE 700-300 QVECTOR CONV WILL ALSO BE STRONGEST TO THE NORTH OF
THE CWA. HOWEVER...THE SRN END OF THE SHRTWV SHOULD STILL BE STRONG
ENOUGH TO SUPPORT SCT SHRA/TSRA MOVING FROM NW WI INTO WRN UPPER MI
THIS AFTERNOON AND THROUGH THE REST OF THE CWA THIS EVENING.
EXPECTED MAX TEMPS AND DEWPOINTS INTO THE MID TO UPPER 60S GIVE CAPE
VALUES INTO THE 1K-2K J/KG RANGE...GREATEST WEST CENTRAL. 0-6KM BULK
SHEAR VALUES IN THE 30-35 KNOT RANGE WILL BE MARGINAL FOR STRONG/SVR
ORGANIZED CONVECTION BUT WITH TSRA MOVING THROUGH DURING PEAK
HEATING GIVING DCAPE VALUES IN THE 500-1000 J/KG RANGE...SOME
ISOLATED STRONG/DAMAGING WIND GUSTS MAY BE POSSIBLE WITH ANY
STRONGER STORMS. THE HIGHER PROBABILITIES FOR SVR STORMS REMAINS TO
THE SOUTH WHERE THE INSTABILITY IS GREATEST...PER SPC DAY1 OUTLOOK.
THE SHRA/TSRA ARE EXPECTED TO PROGRESS THROUGH THE AREA MOVING INTO
THE ERN CWA LATE THIS EVENING AND ENDING OVERNIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 525 AM EDT TUE JUL 9 2013
AFTER A FEW DAYS OF WARM AND ACTIVE WEATHER WITH POCKETS OF HEAVY
RAIN OVER MAINLY WESTERN HALF OF CWA...DEVELOPING TROUGHING ALOFT
ACROSS THE GREAT LAKES AND SFC HIGH ON THE WESTERN EDGE OF THE
TROUGH ALOFT WILL BRING QUIET AND COOLER WEATHER MID TO LATE WEEK.
WARMER TEMPERATURES AND INCREASING SHRA/TSRA CHANCES RETURN FOR THE
WEEKEND AS UPPER HEIGHTS BECOME MORE ZONAL.
OVERALL AGREEMENT THAT BEST CHANCE OF SHRA/TSRA ON WEDNESDAY WILL
BE 12-15Z OVER THE FAR EASTERN CWA. STRONGER TSRA STILL POSSIBLE
WITH MUCAPE UP TO 800J/KG. BETTER SHOT FOR SVR WILL BE FARTHER
SOUTH OVER SOUTHERN WI/NORTHERN IL CLOSER TO WEST-EAST FRONTAL
BOUNDARY AND ON NORTHERN GRADIENT OF HIGHER MLCAPES OVR 1000J/KG.
ANY CHANCES OF SHRA/TSRA OVER EAST QUICKLY END THROUGH MORNING AS
STRONG DEEP LAYER Q-VECTOR DIVERGENCE/SUBSIDENCE SURGES ACROSS
UPPER GREAT LAKES. PRESSURE GRADIENT BRIEFLY BECOMES TIGHT BTWN
THE EXITING LOW PRESSURE TROUGH AND HIGH PRESSURE BUILDING OVER
THE PLAINS. EXPECT BRIEF BUILDING WAVES AND INCREASED SWIM RISK
FOR WEDNESDAY OVER THE LK SUPERIOR BEACHES OF ALGER COUNTY AS
WINDS WILL BE FROM THE WEST TO NORTHWEST. WINDS/WAVES AND
ASSOCIATED HIGHER SWIM RISK SUBSIDES BY LATE AFTN WITH LOSS OF
PRESSURE RISES AND TIGHTER PRESSURE GRADIENT.
HIGH PRESSURE REMAINS MAIN WEATHER FEATURE FOR THU/FRI. TEMPS MAY
DROP INTO THE LOW-MID 40S OVER INTERIOR COOL SPOTS ON THURSDAY NIGHT
WITH LGT SOUTHERLY FLOW AS RIDGE AXIS DRIFTS ACROSS. AIRMASS DOES
NOT APPEAR TO BE NEARLY COLD OR DRY ENOUGH FOR ANY FROST POTENTIAL.
HIGH TEMPS BOTH DAYS SHOULD TOP OUT IN THE MID-UPR 70S AWAY FROM THE
GREAT LAKES. MAY EVEN SEE A FEW SPOTS BACK NEAR 80 DEGREES BY
THURSDAY.
UNCERTAINTY ABOUNDS WITH TIMING AND EXTENT OF NEXT ROUND AND/OR
ROUNDS OF SHRA/TSRA THIS WEEKEND INTO NEXT MONDAY. ECMWF NORMALLY
LEADS WAY IN TERMS OF VERIFICATION...BUT BOY ARE ITS SOLUTIONS IN
THE LAST COUPLE DAYS QUITE INCONSISTENT IN TERMS OF TIMING FOR THE
WEEKEND SHRA/TSRA CHANCES. DOES SEEM LIKE ECMWF IS TRENDING TOWARD
SLOWER IDEA SHOWN BY GFS FOR ARRIVAL OF PRECIP FRIDAY NIGHT. WILL
START TO SHOW TREND OF CHANCE POPS ONLY OVER THE FAR WEST LATE ON
FRIDAY NIGHT WHILE IT STAYS MAINLY DRY ELSEWHERE. UPPER HEIGHTS
FLATTEN OUT SATURDAY ALLOWING SHORTWAVES AND MID-LEVEL WIND MAX TO
SLIDE ACROSS UPPER GREAT LAKES REGION. MAIN SFC LOW WILL BE WELL TO
NORTH CLOSER TO SHARPER TROUGH ALOFT...BUT SW LOW-LEVEL FLOW ALONG
WITH INCREASING MOISTURE AND BUILDING INSTABILITY JUST UPSTREAM
SHOULD RESULT IN AT LEAST A CHANCE OF SHRA/TSRA AHEAD OF SFC-H85
TROUGH THAT MOVES THROUGH BY SUNDAY MORNING. WITH WRLY FLOW
ALOFT...FRONT MAY END UP STALLING OUT LATER IN THE WEEKEND PROVIDING
A FOCUS FOR ADDITIONAL SHRA/TSRA. FOR MOST PART USED CONSENSUS
POPS...BUT DID INCREASE POPS SLIGHTLY OVER THE SOUTH AND EAST CWA
CLOSER TO EXPECTED POSITION OF FRONT PER WPC HAND DRAWN SFC PROGS.
BASED ON GENERAL S/SW GRADIENT FLOW AHEAD OF FRONT AND H85 TEMPS IN
THE MID TEENS...INCREASED TEMPS OVER CONSENSUS GUIDANCE. EXPECT MAX
TEMPS FRIDAY THROUGH SUNDAY IN THE MID-UPR 70S TO AS WARM AS MID
80S. IT WILL ALL DEPEND ON EXTENT OF CLOUDS AND SHRA/TSRA. AFTER MIN
TEMPS IN THE 40S AND 50S MUCH OF THIS WEEK...READINGS RETURN TO THE
WARMER/MUGGIER 60S BY THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 126 AM EDT TUE JUL 9 2013
EXPECT DENSE FOG/VLIFR CONDITIONS TO IMPACT ALL 3 TAF SITES EARLY
THIS MRNG WITH LGT WINDS/HUMID LLVLS UNDER SFC HI PRES/DRIER AIR ALF
DEPICTED ON THE 00Z GRB RAOB. DIURNAL HEATING LATER THIS MRNG SHOULD
ALLOW A GRADUAL RETURN OF VFR WX...FASTEST BY NOON AT IWD WITH DVLPG
DOWNSLOPE S WIND IN ADVANCE OF APRCHG UPR DISTURBANCE/COLD FNT. SOME
SHRA/TS IN ADVANCE OF THESE FEATURES WL ARRIVE OVER THE WRN IWD/CMX
SITES BY THE END OF THE TAF PERIOD AND THEN MOVE E TOWARD SAW DURING
THE EVNG. ALTHOUGH THE RELATIVE DRYNESS OF THE LLVLS SHOULD ALLOW
PREDOMINANT VFR CONDITIONS...POORER CONDITIONS WL BE PSBL UNDER THE
HEAVIER SHRA/TS. UPSLOPE WNW FLOW OFF LK SUP IN THE WAKE OF THE
CONVECTION MIGHT CAUSE PREDOMINANT MVFR WX AT CMX...ESPECIALLY IF
HEAVIER RA FALLS NEARBY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 359 PM EDT MON JUL 8 2013
DENSE FOG REMAINS A CONCERN ACROSS LAKE SUPERIOR THROUGH TUESDAY
MORNING. LIGHT WINDS AND LITTLE AIR MASS MOVEMENT WILL ALLOW FOR THE
REDEVELOPMENT OF AREAS OF DENSE FOG OVERNIGHT. CLEARING SKIES FOR
TUESDAY MORNING SHOULD ALLOW ENOUGH HEATING TO MIX OUT THE MOST
DENSE FOG BY TUESDAY AFTERNOON. PATCHY FOG WILL THEN LINGER INTO
WEDNESDAY BEFORE A COLD FRONT BRINGS DRIER AIR FROM WEST TO EAST
ACROSS THE LAKE. WINDS SHOULD BE LIGHT AND GENERALLY VARIABLE
THROUGH TUESDAY EVENING. THEN...EXPECT WINDS TO VEER TO THE NW AT 15
TO 25 KNOTS...MAINLY ACROSS THE EAST HALF OF THE LAKE...FOR LATE
TUESDAY NIGHT THROUGH WEDNESDAY. HIGH PRESSURE WILL THEN BUILD INTO
THE AREA THURSDAY THROUGH SATURDAY AND BRING LIGHT WINDS UNDER 15
KNOTS FOR MUCH OF THE TIME PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 5 PM EDT /4 PM CDT/ THIS AFTERNOON FOR
LSZ162-240>251-263>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...KC
MARINE...KLUBER
AREA FORECAST DISCUSSION
NWS DULUTH MN
314 PM CDT TUE JUL 9 2013
.SHORT TERM...THROUGH EARLY WEDNESDAY EVENING.
COVERAGE OF SHOWERS AND STORMS HAVE DIMINISHED OVER MUCH OF THE
NORTHLAND THIS AFTERNOON...WITH HIGHEST CONCENTRATION OVER OUR FAR
EASTERN ZONES ALONG AND AHEAD OF THE LOW LEVEL BOUNDARY.
ADDITIONAL ISOLATED SHOWERS WERE OCCURRING BEHIND THIS BOUNDARY
WITH OTHERS ASSOCIATED WITH THE UPPER WAVE OVER SOUTHERN
MANITOBA/NORTHERN NORTH DAKOTA. LATEST HRRR HAS A DECENT HANDLE ON
CURRENT CONVECTION...AND SHOWS COVERAGE REMAINING LIMITED TONIGHT.
WE DO HAVE POPS THIS EVENING OVER MUCH OF THE NORTHLAND...BUT
DECREASE THEM FROM WEST TO EAST TONIGHT. THE THREAT FOR SEVERE STORMS IS
LOW AS BEST CONVERGENCE SHOULD BE EXITING OUR CWA THIS
EVENING...AND STABILITY AND SHEAR ARE NOT REAL SUPPORTIVE GIVEN
THE AMOUNT OF LIFT.
SOME FOG MAY LINGER THIS EVENING AROUND LAKE
SUPERIOR...PARTICULARLY UP THE NORTH SHORE...BUT THEN THAT SHOULD
DIMINISH OVERNIGHT AS WINDS TURN NORTHWEST BEHIND THE FRONT.
WEDNESDAY SHOULD FEATURE PARTLY TO MOSTLY SUNNY SKIES WITH HIGH
PRESSURE BUILDING IN. TEMPERATURES WILL BE IN THE SEVENTIES. WE DO
EXPECT GOOD MIXING WITH STEEP LAPSE RATES. THIS WILL LEAD TO SOME
GUSTY WINDS BY AFTERNOON. SOME STEEPER LAPSE RATES OVER THE
ARROWHEAD AND IT`S PROXIMITY TO THE EXITING UPPER TROUGH SHOULD BE
ENOUGH TO CAUSE SOME THICKER CLOUDS UP THERE BY WEDNESDAY
AFTERNOON. WE LEFT THAT AREA DRY...BUT LATER SHIFTS WILL HAVE TO
MONITOR FOR THE POSSIBLE ADDITION OF A FEW SHOWERS OR
THUNDERSTORMS IN THE AFTERNOON.
.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY.
A LARGE SFC HIGH AND ASSOCIATED UPPER RIDGE WILL BE BUILDING IN
ACROSS THE UPPER MIDWEST WED NIGHT...ALONG WITH DRYING CONDITIONS
AND MOSTLY CLEAR SKIES. RELATIVELY COOL TEMPS COULD DEVELOP EARLY
THUR MORNING UNDER CALM WINDS AND STRONG RADIATIONAL COOLING. SHOULD
SEE MOSTLY SUNNY SKIES ON THURSDAY WITH HIGHS IN THE 70S AROUND THE
LAKE AND 80S INLAND. THUR NIGHT SHOULD REMAIN MOSTLY CLEAR WITH HIGH
PRESSURE IN PLACE. HOWEVER...AS THE SFC HIGH SHIFTS EWD...A RETURN
SLY FLOW WILL DEVELOP AND BEGIN TO USHER IN MORE CLOUD COVER AND A
RICHER MORE UNSTABLE AIR MASS AHEAD OF THE NEXT SFC TROUGH/COLD
FRONT EXPECTED TO MOVE INTO THE REGION THIS WEEKEND. FRIDAY WILL BE
A TRANSITION DAY WITH CLOUDS INCREASING FROM THE W...BUT MINIMAL
PRECIP CHANCES UNTIL LATER FRI NIGHT. MODEL GUIDANCE IS INDICATING
THAT THE SFC FRONT WILL STALL OUT ACROSS NRN MN/WRN LAKE SUPERIOR
ALONG THE NRN/NWRN FRINGES OF AN ELONGATED RIDGE SITUATED OVER THE
MID MS VALLEY/SRN GREAT LAKES REGION. THIS PATTERN WOULD ALLOW FOR A
PROLONGED PERIOD OF SHOWERS AND STORMS THROUGH THE WEEKEND AND INTO
EARLY NEXT WEEK...WITH POTENTIALLY PERIODS OF HEAVY RAIN. WILL NEED
TO MONITOR THIS PATTERN AND ANY CHANGES DURING THE NEXT COUPLE DAYS.
COULD BE DEALING WITH HYDRO ISSUES SAT THROUGH MON.
OTHERWISE...TEMPERATURES REMAIN VERY SEASONAL...WITH HIGHS IN THE
70S AND LOWER 80S AND LOWS IN THE 50S AND LOWER 60S.
&&
.AVIATION...18Z TAF ISSUANCE.
WIDESPREAD RAIN SHOWERS WITH AFTERNOON EMBEDDED THUNDERSTORMS ARE
EXPECTED THE REST OF TODAY BEFORE THE MAIN SFC FRONT PUSHES
THROUGH EARLY THIS EVENING AND ALLOWS CONDITIONS TO DRY OUT LATE
TONIGHT AND TOMORROW. A FEW OF THE STORMS THIS AFTERNOON COULD
PRODUCE HAIL AND VERY STRONG WIND GUSTS. DENSE FOG SHOULD REMAIN
CONFINED TO LAKE SUPERIOR AND THE IMMEDIATE LATE SHORE THROUGH
21Z...AND NOT HAVE TOO MUCH OF AN IMPACT ON THE DLH TERMINAL.
WINDS SHIFT TO THE NW QUICKLY BEHIND THE FRONT TONIGHT AND BECOME
GUSTY WED MORNING.
&&
.POINT TEMPS/POPS...
DLH 54 77 56 79 / 40 0 0 0
INL 53 76 55 82 / 30 10 0 0
BRD 56 78 55 82 / 20 0 0 0
HYR 56 78 52 81 / 50 0 0 0
ASX 54 76 51 79 / 50 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...MELDE
LONG TERM....TENTINGER
AVIATION...TENTINGER
AREA FORECAST DISCUSSION
NWS DULUTH MN
1254 PM CDT TUE JUL 9 2013
.UPDATE...
SHOWERS AND SOME THUNDERSTORMS REMAINED OVER MUCH OF THE
CWA...WITH COVERAGE LIMITED OVER OUR SOUTHERN ZONES FROM HAYWARD
WEST TO THE BRAINERD LAKES REGION. HOWEVER...WE STILL SEE SOME
DEVELOPMENT SO WILL KEEP POPS GOING DOWN THERE THROUGHOUT THE
AFTERNOON. LATEST KDLH IMAGE SHOWS A CELL JUST SOUTHEAST OF FORT
RIPLEY...AND WE SHOULD SEE ADDITIONAL DEVELOPMENT AS WELL IN THIS
MOIST AIRMASS. INSTABILITY HAS WANED A BIT WITH MUCAPE VALUES
500-1000J/KG...BUT THAT SHOULD INCREASE...ESPECIALLY WITH SOME
BREAKS DEVELOPING IN THE CLOUD COVER PER LATEST VISIBLE IMAGERY.
THE FRONTAL BOUNDARY WAS OVER OUT WESTERN ZONES AS OF 18Z AND THE
UPPER WAVE WAS OVER SOUTHERN MB/NORTHERN ND. WE COULD STILL SEE A
SEVERE STORM THIS AFTERNOON AHEAD OF THE COLD FRONT...BUT COVERAGE
SHOULD BE LIMITED DUE TO ALL THE CLOUD COVER. AS MENTIONED
THOUGH...SOME BREAKS IN THE CLOUDS WERE DEVELOPING...AND MAY ALLOW
FURTHER DESTABILIZATION.
THE FOG HAS THINNED QUITE A BIT AROUND LAKE SUPERIOR...BUT
WEBCAMS DO SHOW SOME HANGING AROUND LAKE SUPERIOR...ESPECIALLY UP
THE NORTH SHORE.
&&
.PREV DISCUSSION... /ISSUED 1210 PM CDT TUE JUL 9 2013/
AVIATION...18Z TAF ISSUANCE...
WIDESPREAD RAIN SHOWERS WITH AFTERNOON EMBEDDED THUNDERSTORMS ARE
EXPECTED THE REST OF TODAY BEFORE THE MAIN SFC FRONT PUSHES
THROUGH EARLY THIS EVENING AND ALLOWS CONDITIONS TO DRY OUT LATE
TONIGHT AND TOMORROW. A FEW OF THE STORMS THIS AFTERNOON COULD
PRODUCE HAIL AND VERY STRONG WIND GUSTS. DENSE FOG SHOULD REMAIN
CONFINED TO LAKE SUPERIOR AND THE IMMEDIATE LATE SHORE THROUGH
21Z...AND NOT HAVE TOO MUCH OF AN IMPACT ON THE DLH TERMINAL.
WINDS SHIFT TO THE NW QUICKLY BEHIND THE FRONT TONIGHT AND BECOME
GUSTY WED MORNING.
PREV DISCUSSION... /ISSUED 923 AM CDT TUE JUL 9 2013/
UPDATE...
FOCUS IN THE SHORT TERM IS COVERAGE OF RAIN/STORMS AND THEIR
INTENSITY.
A LINE OF STRONG-SEVERE STORMS WERE MOVING INTO WEST
CENTRAL/NORTHWEST WISCONSIN AS OF MID MORNING...WITH A KMPX RADAR
SHOWING A A NICE AREA OF OUTBOUND VELOCITY FROM 50-60 KT AT TIMES.
THIS LINE WAS MOVING EAST/NORTHEAST 40-45 MPH. AN AREA OF RAIN
WITH SOME EMBEDDED STORMS EXTENDED NORTH INTO NORTHWEST
MINNESOTA/MANITOBA/NORTHWEST ONTARIO AS WELL. RADAR TRENDS SHOW A
DIMINISHING TREND IN WHAT WAS A MORE ORGANIZED AREA OF
SHOWERS/STORMS WITH FEW RETURNS HEADED FOR THE IRON
RANGE/ARROWHEAD. THE FRONT AND MAIN SHORTWAVE ARE STILL
WEST/NORTHWEST OF THE CWA...SO THERE IS AMPLE LIFT THAT NEEDS TO
MOVE THROUGH THE NORTHLAND YET TODAY AND THAT WILL LEAD TO
ADDITIONAL CHANCES FOR STORMS THROUGH THE DAY. WE WILL CONTINUE TO
MAKE SHORT TERM ADJUSTMENTS TO GRIDS ACCOUNTING FOR RADAR TRENDS.
THE NAM SUGGESTS COVERAGE SHOULD INCREASE THROUGH THE DAY. THE 12Z
KMPX/KINL SOUNDINGS EACH HAD PWAT VALUES OF 1.75 AND 1.41 INCHES.
SPC MESOANALYSIS DEPICTED AROUND 30KT DEEP LAYER SHEAR WITH
500-1500J/KG OF MUCAPE. 11Z HRRR WAS DOING AN OK JOB DEPICTING 14Z
RAIN/STORMS...AND ALSO SHOWS THE RAIN SPLITTING WITH ADDITIONAL
SCATTERED SHOWERS/STORMS DEVELOPING THIS AFTERNOON INTO THE
EVENING.
SHORT TERM SEVERE THREAT WILL BE OVER OUR NORTHWEST WISCONSIN
ZONES OVER THE NEXT 1 TO 3 HOURS...THEN SHIFTS AHEAD OF THE FRONT
THIS AFTERNOON AS IT MOVES THROUGH THE CWA.
PREV DISCUSSION... /ISSUED 621 AM CDT TUE JUL 9 2013/
AVIATION.../12Z TAF ISSUANCE/
EARLY MORNING LIFR/IFR CONDITIONS DUE TO FOG ACROSS PARTS OF NE
MINNESOTA AND NW WISCONSIN...INCLUDING KDLH AND KHIB...SHOULD LIFT
AND BREAK UP WITHIN THE NEXT FEW HOURS. SHOWERS AND THUNDERSTORMS
ARE LIKELY ACROSS THE NORTHLAND TODAY AND EARLY THIS EVENING. THE
SHOWERS AND STORMS COULD BRING BRIEF MVFR CONDITIONS DUE TO LOW
CIGS AND VSBY RESTRICTIONS FROM RAIN. THE REGION WILL BEGIN TO
CLEAR THIS EVENING AS HIGH PRESSURE BEGINS TO MOVE INTO THE
NORTHERN PLAINS AND UPPER MIDWEST. EXPECT VFR CONDITIONS LATE THIS
EVENING AND WEDNESDAY MORNING. THE VERY LIGHT WINDS WILL INCREASE
LATE THIS AFTERNOON AND THIS EVENING AND BECOME NW IN THE WAKE OF
A PASSING COLD FRONT.
PREV DISCUSSION... /ISSUED 453 AM CDT TUE JUL 9 2013/
SHORT TERM...TODAY AND TONIGHT.
CURRENT REGIONAL RADAR IMAGERY SHOWS A LARGE AREA OF SHRA/TSTORMS
ASSOCIATED WITH A MID-LEVEL TROUGH EXTENDING FROM SRN MANITOBA...ALONG
THE WESTERN MN BORDER...INTO IOWA. AT THIS TIME...THE STRONGEST
STORMS...LOCATED WITH A STRENGTHEN MCS...IS FOUND EXITING EASTERN
SD AND MOVING INTO THE SW PORTION OF MN.
LATEST HIGH RES MODEL RUNS OF THE WRF/HRRR HAVE A RELATIVELY DECENT
HANDLE ON THE CURRENT CONVECTION AND BOTH SHOW THE STORMS
DECREASING SOMEWHAT...BUT OVERALL HOLDING TOGETHER AS THE LINE
MARCHES EAST ACROSS MINNESOTA THIS MORNING. HAVE ADJUSTED POPS
THIS MORNING TO LIKELY USING THE CURRENT DISTANCE/SPEED OF THE
LINE OF STORMS FOR TIMING. AT THE CURRENT SPEED...THE LEADING EDGE
OF THESE STORMS WILL ARRIVE IN THE KINL TO KBRD AREA AROUND 700 TO
800 AM...REACHING A LINE FROM KHIB TO KDLH AND EXTENDING SOUTH
ALONG THE INTERSTATE 35 CORRIDOR AROUND 10-11 AM. THE LIMITING
FACTOR WILL BE IF THE MCS TRACKING ACROSS CENTRAL MINNESOTA CUTS
OFF THE MOISTURE TO STORMS FURTHER NORTH.
SHIFTING FOCUS TO ADDITIONAL THUNDER DEVELOPMENT THIS AFTERNOON
ALONG A SFC COLD FRONT. THE SEVERITY AND COVERAGE OF THE
AFTERNOON CONVECTION WILL BE HIGHLY DEPENDENT ON THE HOW WORKED
OVER THE REGION BECOMES WITH THE STORMS THIS MORNING. HAVE
BROADBRUSH SCT THUNDER OVER MN ZONES...WITH LIKELY ACROSS THE TIP
OF THE ARROWHEAD AND NRN WIS AREAS THROUGH THIS EVENING.
LONG TERM [WEDNESDAY - MONDAY]
THE BEGINNING OF THE PERIOD LOOKS RELATIVELY QUIET. HIGH PRESSURE
AND NW FLOW SHOULD PROVIDE MILD WEATHER AND SUNNY SKIES ACROSS THE
NORTHLAND. WE EXPECT A WARMING TREND LATE THIS WEEK...LIKELY
CULMINATING ON FRIDAY...AS A MID/UPPER LEVEL RIDGE BUILDS INTO THE
UPPER MIDWEST AND SOUTHERLY WINDS INCREASE ACROSS THE NORTHLAND.
MUCH OF THE NORTHLAND...SAVE THE IMMEDIATE NORTH SHORE...SHOULD HAVE
TEMPERATURES AT LEAST IN THE LOW TO MID 80S ON FRIDAY. I INCREASED
THE FRIDAY HIGH TEMPERATURES SINCE I THINK THE MOS GUIDANCE IS TOO
WEIGHTED TOWARDS CLIMATOLOGY...AND WE MIGHT NEED TO INCREASE EVEN
THE HIGHS EVEN MORE.
A COLD FRONT WILL APPROACH THE NORTHLAND LATE THIS WEEK AND THEN
MIGHT STALL OR SLOWLY PROGRESS THROUGH THE REGION THROUGH EARLY NEXT
WEEK. THIS WILL BRING A PERIOD OF SEVERAL DAYS WHERE THE NORTHLAND
WILL HAVE CHANCES OF SHOWERS AND THUNDERSTORMS. FOR NOW...LATE
FRIDAY NIGHT AND SATURDAY MORNING APPEARS TO BE THE PERIOD IN WHICH
THE NORTHLAND WILL HAVE THE GREATEST CHANCES OF SHOWERS AND STORMS.
THE MODELS ARE IN FAIRLY GOOD AGREEMENT THAT THE APPROACHING/PASSING
COLD FRONT WILL BRING WIDESPREAD RAINFALL OF AT LEAST A TENTH TO
QUARTER INCH OF RAIN TO THE NORTHLAND.
&&
.POINT TEMPS/POPS...
DLH 54 77 54 79 / 40 0 0 0
INL 53 76 50 82 / 10 10 0 0
BRD 56 78 56 83 / 10 0 0 0
HYR 56 78 51 84 / 50 0 0 0
ASX 54 76 52 80 / 50 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR LSZ121-
140>148.
&&
$$
SHORT TERM...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1210 PM CDT TUE JUL 9 2013
.AVIATION...18Z TAF ISSUANCE...
WIDESPREAD RAIN SHOWERS WITH AFTERNOON EMBEDDED THUNDERSTORMS ARE
EXPECTED THE REST OF TODAY BEFORE THE MAIN SFC FRONT PUSHES
THROUGH EARLY THIS EVENING AND ALLOWS CONDITIONS TO DRY OUT LATE
TONIGHT AND TOMORROW. A FEW OF THE STORMS THIS AFTERNOON COULD
PRODUCE HAIL AND VERY STRONG WIND GUSTS. DENSE FOG SHOULD REMAIN
CONFINED TO LAKE SUPERIOR AND THE IMMEDIATE LATE SHORE THROUGH
21Z...AND NOT HAVE TOO MUCH OF AN IMPACT ON THE DLH TERMINAL.
WINDS SHIFT TO THE NW QUICKLY BEHIND THE FRONT TONIGHT AND BECOME
GUSTY WED MORNING.
&&
.PREV DISCUSSION... /ISSUED 923 AM CDT TUE JUL 9 2013/
UPDATE...
FOCUS IN THE SHORT TERM IS COVERAGE OF RAIN/STORMS AND THEIR
INTENSITY.
A LINE OF STRONG-SEVERE STORMS WERE MOVING INTO WEST
CENTRAL/NORTHWEST WISCONSIN AS OF MID MORNING...WITH A KMPX RADAR
SHOWING A A NICE AREA OF OUTBOUND VELOCITY FROM 50-60 KT AT TIMES.
THIS LINE WAS MOVING EAST/NORTHEAST 40-45 MPH. AN AREA OF RAIN
WITH SOME EMBEDDED STORMS EXTENDED NORTH INTO NORTHWEST
MINNESOTA/MANITOBA/NORTHWEST ONTARIO AS WELL. RADAR TRENDS SHOW A
DIMINISHING TREND IN WHAT WAS A MORE ORGANIZED AREA OF
SHOWERS/STORMS WITH FEW RETURNS HEADED FOR THE IRON
RANGE/ARROWHEAD. THE FRONT AND MAIN SHORTWAVE ARE STILL
WEST/NORTHWEST OF THE CWA...SO THERE IS AMPLE LIFT THAT NEEDS TO
MOVE THROUGH THE NORTHLAND YET TODAY AND THAT WILL LEAD TO
ADDITIONAL CHANCES FOR STORMS THROUGH THE DAY. WE WILL CONTINUE TO
MAKE SHORT TERM ADJUSTMENTS TO GRIDS ACCOUNTING FOR RADAR TRENDS.
THE NAM SUGGESTS COVERAGE SHOULD INCREASE THROUGH THE DAY. THE 12Z
KMPX/KINL SOUNDINGS EACH HAD PWAT VALUES OF 1.75 AND 1.41 INCHES.
SPC MESOANALYSIS DEPICTED AROUND 30KT DEEP LAYER SHEAR WITH
500-1500J/KG OF MUCAPE. 11Z HRRR WAS DOING AN OK JOB DEPICTING 14Z
RAIN/STORMS...AND ALSO SHOWS THE RAIN SPLITTING WITH ADDITIONAL
SCATTERED SHOWERS/STORMS DEVELOPING THIS AFTERNOON INTO THE
EVENING.
SHORT TERM SEVERE THREAT WILL BE OVER OUR NORTHWEST WISCONSIN
ZONES OVER THE NEXT 1 TO 3 HOURS...THEN SHIFTS AHEAD OF THE FRONT
THIS AFTERNOON AS IT MOVES THROUGH THE CWA.
PREV DISCUSSION... /ISSUED 621 AM CDT TUE JUL 9 2013/
AVIATION.../12Z TAF ISSUANCE/
EARLY MORNING LIFR/IFR CONDITIONS DUE TO FOG ACROSS PARTS OF NE
MINNESOTA AND NW WISCONSIN...INCLUDING KDLH AND KHIB...SHOULD LIFT
AND BREAK UP WITHIN THE NEXT FEW HOURS. SHOWERS AND THUNDERSTORMS
ARE LIKELY ACROSS THE NORTHLAND TODAY AND EARLY THIS EVENING. THE
SHOWERS AND STORMS COULD BRING BRIEF MVFR CONDITIONS DUE TO LOW
CIGS AND VSBY RESTRICTIONS FROM RAIN. THE REGION WILL BEGIN TO
CLEAR THIS EVENING AS HIGH PRESSURE BEGINS TO MOVE INTO THE
NORTHERN PLAINS AND UPPER MIDWEST. EXPECT VFR CONDITIONS LATE THIS
EVENING AND WEDNESDAY MORNING. THE VERY LIGHT WINDS WILL INCREASE
LATE THIS AFTERNOON AND THIS EVENING AND BECOME NW IN THE WAKE OF
A PASSING COLD FRONT.
PREV DISCUSSION... /ISSUED 453 AM CDT TUE JUL 9 2013/
SHORT TERM...TODAY AND TONIGHT.
CURRENT REGIONAL RADAR IMAGERY SHOWS A LARGE AREA OF SHRA/TSTORMS
ASSOCIATED WITH A MID-LEVEL TROUGH EXTENDING FROM SRN MANITOBA...ALONG
THE WESTERN MN BORDER...INTO IOWA. AT THIS TIME...THE STRONGEST
STORMS...LOCATED WITH A STRENGTHEN MCS...IS FOUND EXITING EASTERN
SD AND MOVING INTO THE SW PORTION OF MN.
LATEST HIGH RES MODEL RUNS OF THE WRF/HRRR HAVE A RELATIVELY DECENT
HANDLE ON THE CURRENT CONVECTION AND BOTH SHOW THE STORMS
DECREASING SOMEWHAT...BUT OVERALL HOLDING TOGETHER AS THE LINE
MARCHES EAST ACROSS MINNESOTA THIS MORNING. HAVE ADJUSTED POPS
THIS MORNING TO LIKELY USING THE CURRENT DISTANCE/SPEED OF THE
LINE OF STORMS FOR TIMING. AT THE CURRENT SPEED...THE LEADING EDGE
OF THESE STORMS WILL ARRIVE IN THE KINL TO KBRD AREA AROUND 700 TO
800 AM...REACHING A LINE FROM KHIB TO KDLH AND EXTENDING SOUTH
ALONG THE INTERSTATE 35 CORRIDOR AROUND 10-11 AM. THE LIMITING
FACTOR WILL BE IF THE MCS TRACKING ACROSS CENTRAL MINNESOTA CUTS
OFF THE MOISTURE TO STORMS FURTHER NORTH.
SHIFTING FOCUS TO ADDITIONAL THUNDER DEVELOPMENT THIS AFTERNOON
ALONG A SFC COLD FRONT. THE SEVERITY AND COVERAGE OF THE
AFTERNOON CONVECTION WILL BE HIGHLY DEPENDENT ON THE HOW WORKED
OVER THE REGION BECOMES WITH THE STORMS THIS MORNING. HAVE
BROADBRUSH SCT THUNDER OVER MN ZONES...WITH LIKELY ACROSS THE TIP
OF THE ARROWHEAD AND NRN WIS AREAS THROUGH THIS EVENING.
LONG TERM [WEDNESDAY - MONDAY]
THE BEGINNING OF THE PERIOD LOOKS RELATIVELY QUIET. HIGH PRESSURE
AND NW FLOW SHOULD PROVIDE MILD WEATHER AND SUNNY SKIES ACROSS THE
NORTHLAND. WE EXPECT A WARMING TREND LATE THIS WEEK...LIKELY
CULMINATING ON FRIDAY...AS A MID/UPPER LEVEL RIDGE BUILDS INTO THE
UPPER MIDWEST AND SOUTHERLY WINDS INCREASE ACROSS THE NORTHLAND.
MUCH OF THE NORTHLAND...SAVE THE IMMEDIATE NORTH SHORE...SHOULD HAVE
TEMPERATURES AT LEAST IN THE LOW TO MID 80S ON FRIDAY. I INCREASED
THE FRIDAY HIGH TEMPERATURES SINCE I THINK THE MOS GUIDANCE IS TOO
WEIGHTED TOWARDS CLIMATOLOGY...AND WE MIGHT NEED TO INCREASE EVEN
THE HIGHS EVEN MORE.
A COLD FRONT WILL APPROACH THE NORTHLAND LATE THIS WEEK AND THEN
MIGHT STALL OR SLOWLY PROGRESS THROUGH THE REGION THROUGH EARLY NEXT
WEEK. THIS WILL BRING A PERIOD OF SEVERAL DAYS WHERE THE NORTHLAND
WILL HAVE CHANCES OF SHOWERS AND THUNDERSTORMS. FOR NOW...LATE
FRIDAY NIGHT AND SATURDAY MORNING APPEARS TO BE THE PERIOD IN WHICH
THE NORTHLAND WILL HAVE THE GREATEST CHANCES OF SHOWERS AND STORMS.
THE MODELS ARE IN FAIRLY GOOD AGREEMENT THAT THE APPROACHING/PASSING
COLD FRONT WILL BRING WIDESPREAD RAINFALL OF AT LEAST A TENTH TO
QUARTER INCH OF RAIN TO THE NORTHLAND.
&&
.POINT TEMPS/POPS...
DLH 55 76 54 79 / 40 0 0 0
INL 54 77 50 82 / 10 10 0 0
BRD 56 79 56 83 / 10 0 0 0
HYR 57 80 51 84 / 50 0 0 0
ASX 55 76 52 80 / 50 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR LSZ121-
140>148.
&&
$$
SHORT TERM...MELDE
AVIATION...TENTINGER
AREA FORECAST DISCUSSION
NWS DULUTH MN
923 AM CDT TUE JUL 9 2013
.UPDATE...
FOCUS IN THE SHORT TERM IS COVERAGE OF RAIN/STORMS AND THEIR
INTENSITY.
A LINE OF STRONG-SEVERE STORMS WERE MOVING INTO WEST
CENTRAL/NORTHWEST WISCONSIN AS OF MID MORNING...WITH A KMPX RADAR
SHOWING A A NICE AREA OF OUTBOUND VELOCITY FROM 50-60 KT AT TIMES.
THIS LINE WAS MOVING EAST/NORTHEAST 40-45 MPH. AN AREA OF RAIN
WITH SOME EMBEDDED STORMS EXTENDED NORTH INTO NORTHWEST
MINNESOTA/MANITOBA/NORTHWEST ONTARIO AS WELL. RADAR TRENDS SHOW A
DIMINISHING TREND IN WHAT WAS A MORE ORGANIZED AREA OF
SHOWERS/STORMS WITH FEW RETURNS HEADED FOR THE IRON
RANGE/ARROWHEAD. THE FRONT AND MAIN SHORTWAVE ARE STILL
WEST/NORTHWEST OF THE CWA...SO THERE IS AMPLE LIFT THAT NEEDS TO
MOVE THROUGH THE NORTHLAND YET TODAY AND THAT WILL LEAD TO
ADDITIONAL CHANCES FOR STORMS THROUGH THE DAY. WE WILL CONTINUE TO
MAKE SHORT TERM ADJUSTMENTS TO GRIDS ACCOUNTING FOR RADAR TRENDS.
THE NAM SUGGESTS COVERAGE SHOULD INCREASE THROUGH THE DAY. THE 12Z
KMPX/KINL SOUNDINGS EACH HAD PWAT VALUES OF 1.75 AND 1.41 INCHES.
SPC MESOANALYSIS DEPICTED AROUND 30KT DEEP LAYER SHEAR WITH
500-1500J/KG OF MUCAPE. 11Z HRRR WAS DOING AN OK JOB DEPICTING 14Z
RAIN/STORMS...AND ALSO SHOWS THE RAIN SPLITTING WITH ADDITIONAL
SCATTERED SHOWERS/STORMS DEVELOPING THIS AFTERNOON INTO THE
EVENING.
SHORT TERM SEVERE THREAT WILL BE OVER OUR NORTHWEST WISCONSIN
ZONES OVER THE NEXT 1 TO 3 HOURS...THEN SHIFTS AHEAD OF THE FRONT
THIS AFTERNOON AS IT MOVES THROUGH THE CWA.
&&
.PREV DISCUSSION... /ISSUED 621 AM CDT TUE JUL 9 2013/
AVIATION.../12Z TAF ISSUANCE/
EARLY MORNING LIFR/IFR CONDITIONS DUE TO FOG ACROSS PARTS OF NE
MINNESOTA AND NW WISCONSIN...INCLUDING KDLH AND KHIB...SHOULD LIFT
AND BREAK UP WITHIN THE NEXT FEW HOURS. SHOWERS AND THUNDERSTORMS
ARE LIKELY ACROSS THE NORTHLAND TODAY AND EARLY THIS EVENING. THE
SHOWERS AND STORMS COULD BRING BRIEF MVFR CONDITIONS DUE TO LOW
CIGS AND VSBY RESTRICTIONS FROM RAIN. THE REGION WILL BEGIN TO
CLEAR THIS EVENING AS HIGH PRESSURE BEGINS TO MOVE INTO THE
NORTHERN PLAINS AND UPPER MIDWEST. EXPECT VFR CONDITIONS LATE THIS
EVENING AND WEDNESDAY MORNING. THE VERY LIGHT WINDS WILL INCREASE
LATE THIS AFTERNOON AND THIS EVENING AND BECOME NW IN THE WAKE OF
A PASSING COLD FRONT.
PREV DISCUSSION... /ISSUED 453 AM CDT TUE JUL 9 2013/
SHORT TERM...TODAY AND TONIGHT.
CURRENT REGIONAL RADAR IMAGERY SHOWS A LARGE AREA OF SHRA/TSTORMS
ASSOCIATED WITH A MID-LEVEL TROUGH EXTENDING FROM SRN MANITOBA...ALONG
THE WESTERN MN BORDER...INTO IOWA. AT THIS TIME...THE STRONGEST
STORMS...LOCATED WITH A STRENGTHEN MCS...IS FOUND EXITING EASTERN
SD AND MOVING INTO THE SW PORTION OF MN.
LATEST HIGH RES MODEL RUNS OF THE WRF/HRRR HAVE A RELATIVELY DECENT
HANDLE ON THE CURRENT CONVECTION AND BOTH SHOW THE STORMS
DECREASING SOMEWHAT...BUT OVERALL HOLDING TOGETHER AS THE LINE
MARCHES EAST ACROSS MINNESOTA THIS MORNING. HAVE ADJUSTED POPS
THIS MORNING TO LIKELY USING THE CURRENT DISTANCE/SPEED OF THE
LINE OF STORMS FOR TIMING. AT THE CURRENT SPEED...THE LEADING EDGE
OF THESE STORMS WILL ARRIVE IN THE KINL TO KBRD AREA AROUND 700 TO
800 AM...REACHING A LINE FROM KHIB TO KDLH AND EXTENDING SOUTH
ALONG THE INTERSTATE 35 CORRIDOR AROUND 10-11 AM. THE LIMITING
FACTOR WILL BE IF THE MCS TRACKING ACROSS CENTRAL MINNESOTA CUTS
OFF THE MOISTURE TO STORMS FURTHER NORTH.
SHIFTING FOCUS TO ADDITIONAL THUNDER DEVELOPMENT THIS AFTERNOON
ALONG A SFC COLD FRONT. THE SEVERITY AND COVERAGE OF THE
AFTERNOON CONVECTION WILL BE HIGHLY DEPENDENT ON THE HOW WORKED
OVER THE REGION BECOMES WITH THE STORMS THIS MORNING. HAVE
BROADBRUSH SCT THUNDER OVER MN ZONES...WITH LIKELY ACROSS THE TIP
OF THE ARROWHEAD AND NRN WIS AREAS THROUGH THIS EVENING.
LONG TERM [WEDNESDAY - MONDAY]
THE BEGINNING OF THE PERIOD LOOKS RELATIVELY QUIET. HIGH PRESSURE
AND NW FLOW SHOULD PROVIDE MILD WEATHER AND SUNNY SKIES ACROSS THE
NORTHLAND. WE EXPECT A WARMING TREND LATE THIS WEEK...LIKELY
CULMINATING ON FRIDAY...AS A MID/UPPER LEVEL RIDGE BUILDS INTO THE
UPPER MIDWEST AND SOUTHERLY WINDS INCREASE ACROSS THE NORTHLAND.
MUCH OF THE NORTHLAND...SAVE THE IMMEDIATE NORTH SHORE...SHOULD HAVE
TEMPERATURES AT LEAST IN THE LOW TO MID 80S ON FRIDAY. I INCREASED
THE FRIDAY HIGH TEMPERATURES SINCE I THINK THE MOS GUIDANCE IS TOO
WEIGHTED TOWARDS CLIMATOLOGY...AND WE MIGHT NEED TO INCREASE EVEN
THE HIGHS EVEN MORE.
A COLD FRONT WILL APPROACH THE NORTHLAND LATE THIS WEEK AND THEN
MIGHT STALL OR SLOWLY PROGRESS THROUGH THE REGION THROUGH EARLY NEXT
WEEK. THIS WILL BRING A PERIOD OF SEVERAL DAYS WHERE THE NORTHLAND
WILL HAVE CHANCES OF SHOWERS AND THUNDERSTORMS. FOR NOW...LATE
FRIDAY NIGHT AND SATURDAY MORNING APPEARS TO BE THE PERIOD IN WHICH
THE NORTHLAND WILL HAVE THE GREATEST CHANCES OF SHOWERS AND STORMS.
THE MODELS ARE IN FAIRLY GOOD AGREEMENT THAT THE APPROACHING/PASSING
COLD FRONT WILL BRING WIDESPREAD RAINFALL OF AT LEAST A TENTH TO
QUARTER INCH OF RAIN TO THE NORTHLAND.
&&
.POINT TEMPS/POPS...
DLH 73 55 76 54 / 60 40 0 0
INL 76 54 77 50 / 70 10 0 0
BRD 83 56 79 56 / 70 20 0 0
HYR 83 57 80 51 / 70 60 0 0
ASX 74 55 76 52 / 70 60 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...DENSE FOG ADVISORY UNTIL NOON CDT TODAY FOR MNZ020-021-037.
WI...DENSE FOG ADVISORY UNTIL NOON CDT TODAY FOR WIZ001>003.
LS...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR LSZ121-
140>148.
&&
$$
SHORT TERM...MELDE
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
710 AM CDT TUE JUL 9 2013
.UPDATE...
12Z AVIATION DISCUSSION ADDED BELOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 410 AM CDT TUE JUL 9 2013
MAIN CONCERN IN THE SHORT TERM REVOLVES ON EVOLUTION OF STORMS
CURRENTLY ACROSS THE DAKOTAS THROUGH THE MORNING...FOLLOWED BY WHERE
THUNDERSTORMS REDEVELOP THIS AFTERNOON AND TRAVEL THIS EVENING. IT
IS THE AFTERNOON/EVENING ACTIVITY THAT WILL ALSO HAVE A SEVERE
THREAT. WIND AND HAIL WILL BE THE PRIMARY THREATS...THOUGH DEPENDING
ON WHERE BOUNDARIES ARE LEFT OVER FROM CONVECTION THIS
MORNING...THERE WILL ALSO BE THE SMALL CHANCE FOR TORNADOES ON ANY
LEFT OVER OUTFLOW BOUNDARIES.
AT 3 AM...WE WERE DEALING WITH A BIFURCATED LLJ IN TERMS OF MOISTURE
TRANSPORT MAXIMA...WITH ONE BRANCH DRIVING CONVECTION CURRENTLY
MOVING ACROSS THE DAKOTAS AND THE OTHER DRIVING ANOTHER CLUSTER
ALONG THE NEB/IA BORDER. THIS SRN BRANCH WILL TRACK ACROSS IA
THROUGH THE MORNING...KEEPING THAT CONVECTION SOUTH OF MN WHILE
BECOMING THE MAIN LLJ FOR POTENTIAL AFTERNOON ACTIVITY.
FOR THE MPX AREA...IT IS THE MCS THIS MORNING OVER SODAK THAT WILL
BE OUR PROBLEM. 3Z RAP MUCAPE ANALYSIS SHOWS A RIBBON OF 1000-1500
J/KG OF MUCAPE EXTENDING FROM THE MADISON/CANBY AREA...ESE TROUGH
ROCHESTER AND LA CROSSE. AS A RESULT...ANTICIPATE THIS BAND OF
THUNDERSTORMS WILL CONTINUE ESE ALONG THIS CAPE GRADIENT. AT ITS
CURRENT PACE...SHOULD ENTER WRN MN SHORTLY BEFORE 5 AM...REACH THE
I-35 CORRIDOR BETWEEN 7 AND 8 AM AND EVENTUALLY THE LSE/EAU AREAS BY
LATE MORNING. THE BULK OF THE CONVECTION WITH THIS LINE SHOULD TRACK
SOUTH OF I-94 THIS MORNING. AS FOR SEVERE THREAT...THE STRONG/SEVERE
LINE OF STORMS THAT MOVED ACROSS SODAK HAS NOW MERGED WITH THE WAA
ACTIVITY THAT HAD DEVELOPED OUT AHEAD OF IT...WITH ONE LINE NOW
EVIDENT ON REGIONAL RADAR ANALYSIS. WILL HAVE TO WATCH HOW THIS LINE
EVOLVES OVER THE NEXT HOUR TO SEE WHAT KIND OF SEVERE THREAT IT WILL
POSE. IN THE NEXT HOUR...IF IT BEGINS TO BOW OUT AND
ACCELERATE...THEN A WIND THREAT WILL EXIST THROUGH THE MORNING AS IT
TRACKS ACROSS MN. WITH THE RAP AT 3Z ANALYZING 20-30 KTS OF 0-3KM
SHEAR OUT AHEAD OF THE SYSTEM...IT IS PLAUSIBLE THAT THAT COULD
HAPPEN...THOUGH IN THE END IT MAY BE DIFFICULT TO GET ANY SEVERE
STRENGTH WINDS THROUGH THE STABLE BOUNDARY LAYER...SO AGREE WITH SPC
MCD THAT SEVERE THREAT WILL BE FAIRLY MARGINAL.
FOR THIS AFTERNOON...MANY A QUESTION MARKS STILL REMAIN IN PLACE.
THIS BIGGEST ISSUE IS HOW WILL STORMS THIS MORNING IMPACT WHAT
HAPPENS LATER. THE MAIN QUESTION IS DOES THE ATMOSPHERE HAVE ENOUGH
TIME TO RECHARGE FROM STORMS MOVING THROUGH LARGELY IN THE 10-18Z
TIME FRAME? FIRST WORD OF WARNING FOR THE ARM CHAIR FORECASTERS OUT
THERE...THE CAMS MAY NOT BE ALL THAT RELIABLE FOR WHAT HAPPENS LATER
THIS AFTERNOON AS ALL OF THEM ARE HANDLING CURRENT CONVECTION QUITE
POORLY /INCLUDING ALL MEMBERS OF THE 3Z HOPWRF/. PROBLEM
IS...OUTSIDE OF THE SPCWRF...NONE OF THE CAMS SNOW THUNDERSTORMS
MOVING ACROSS THE AREA OUTLINED IN THE PARAGRAPH ABOVE...MANY
/INCLUDING THE HOPWRF MEMBERS/ HAVE NOTHING MOVING ACROSS THE MPX
AREA THIS MORNING...SO HARD TO PUT MUCH STOCK IN WHAT THEY ARE DOING
THIS AFTERNOON. THE ONLY ONE TO BE SOMEWHAT CLOSE TO REALITY THIS
MORNING /SPCWRF/...SHOWS VERY LITTLE CONVECTION REDEVELOPING IN THE
MPX AREA THIS AFTERNOON.
CERTAINLY A BIG PLUS FOR THE AFTERNOON...IS OVER THE LAST 24
HOURS...MODELS HAVE SLOWED UP THE PROGRESSION OF THE FRONT ACROSS
THE MPX AREA...WHICH LIKELY EXPLAINS WHY HIGHER SEVERE PROBABILITIES
WERE PULLED NORTHWEST WITH THE DAY1 SPC CONVECTIVE OUTLOOK. CURRENT
MODEL BLEND WOULD SAY THE FRONT MOVES INTO THE NW MPX CWA AROUND
20Z...THE TWIN CITIES AROUND 00Z AND FINALLY CLEARS EAU AREA SHORTLY
AFTER 3Z. THIS PUTS THE FRONT ACROSS MUCH OF THE AREA DURING PEAK
HEATING...THOUGH IT IS STILL DEBATABLE HOW MUCH HEATING WE WILL SEE
BEHIND THE MORNING CONVECTION. IF CURRENT FORECAST WERE TO
HOLD...WITH TEMPERATURES REBOUNDING INTO THE MID 80S TO NEAR
90...WITH DEWPS IN THE LOWER 70S...THEN WE SHOULD HAVE NO PROBLEM
GENERATING 2000-3500 J/KG OF MLCAPE AHEAD OF THE BOUNDARY AS THE
NAM/GFS DO. FROM THE SHEAR PERSPECTIVE...A 40-60 KT MID LEVEL JET
MOVING IN WITH THE UPPER WAVE THIS AFTERNOON/EVENING WILL PROVIDE
PLENTY OF DEEP LAYER SHEAR TO SUPPORT UPDRAFT ROTATION AND STORM
ORGANIZATION...BUT THE 0-3KM SHEAR IS LOOKING MORE SUSPECT ACROSS
THE MPX AREA TO REALLY DRIVE UP A TORNADO THREAT. THE REASON FOR THE
POOR LOW LEVEL SHEAR IS THAT THE PRESSURE PATTERN AHEAD OF THE FRONT
WILL BE FAIRLY BAGGY...WITH LIGHT PREFRONTAL WINDS EXPECTED. IN
ADDITION...THE CORE OF A 30-40 KT LLJ WILL EXTEND FROM CENTRAL IA
TOWARD NE WIS...STAYING JUST SE OF THE MPX AREA. COMBINED...THE WEAK
SFC WINDS AND BETTER LLJ BEING JUST SE OF THE MPX CWA RESULT IN
MARGINAL 0-1 KM AND 0-3 KM SHEAR /MAINLY 20 KTS OR LESS/. BESIDE THE
WEAKER SHEAR...THE WEAK SFC WINDS OUT AHEAD OF THE FRONT WILL ALSO
LIMIT THE AMOUNT OF CONVERGENCE ALONG IT...WHICH MAY HELP EXPLAIN
WHY MANY OF THE CAMS /OUTSIDE OF THE 3Z HOPWRF/ STRUGGLE TO GENERATE
MUCH CONVECTION ALONG THE BOUNDARY THIS AFTERNOON.
IN SUMMARY...CONFIDENCE IS HIGH THAT MCS CURRENTLY OVER ERN SODAK
WILL TRACK ACROSS AREAS SOUTH OF I-94 THIS MORNING. BECAUSE OF
THIS...CONFIDENCE IN HOW THE AFTERNOON PLAYS OUT IS CONSIDERABLY
DIMINISHED. BUT...GIVEN FRONTAL TIMING...EXPECT AT LEAST SCT STORMS
TO DEVELOP ALONG THE FRONT BETWEEN 19Z AND 21Z THAT WILL THEN TRACK
SE THIS EVENING WITH THE FRONT. GIVEN DEGREE OF INSTABILITY AND BULK
SHEAR...LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY THREAT.
THE WEAKER LOW LEVEL SHEAR MEANS THAT UNLESS A STORM CAN LATCH ON TO
A REMNANT OUTFLOW BOUNDARY...THE TORNADO THREAT APPEARS TO BE
RELATIVELY LOW...THOUGH NOT NEGLIGIBLE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 410 AM CDT TUE JUL 9 2013
THE FIRST HALF OF THE PERIOD WILL START OFF DRY AS LARGE SCALE
SUBSIDENCE DOWNSTREAM OF THE UPPER LEVEL RIDGE AXIS BUILDS AN AREA
OF SURFACE HIGH PRESSURE ACROSS THE UPPER MIDWEST. FORECAST
SOUNDINGS SHOW A DRY PROFILE WITH PWATS ONLY AROUND 0.75
INCHES...ALONG WITH LITTLE POTENTIAL FOR CLOUDS DURING THE DAY ON
WEDNESDAY. WINDS WILL GO CALM OVERNIGHT ALLOWING AN INVERSION TO SET
UP AND TEMPERATURES TO COOL DOWN TO THE UPPER 50S ACROSS MOST
LOCATIONS...WITH LOW 60S EXPECTED IN AND AROUND THE METRO DO TO THE
HEAT ISLAND. THURSDAY WILL BE DRY AS WELL WITH THE SURFACE HIGH
STILL SUPPRESSING ANY CHANCE OF PRECIP. BY THURSDAY NIGHT THE SURFACE
HIGH WILL DRIFT EASTWARD AS THE THERMAL RIDGE APPROACHES FROM THE
WEST...AND SOUTHERLY WINDS ON THE BACK SIDE WILL KEEP OVERNIGHT LOWS
IN THE MID TO UPPER 60S ACROSS WESTERN MINNESOTA. FRIDAY SHOULD BE
MUCH WARMER THAN CURRENTLY FORECAST BY THE NUMERICAL MODELS. BOTH
THE GFS AND ECMWF 09.00 HAVE H850 TEMPS 20-22C...WITH SOUTHERLY
WINDS OF 30KTS...YET FOR SOME REASON THE FORECAST SOUNDINGS ONLY
SHOW MIXING UP TO AROUND 900MB. THIS IS CONTRADICTORY TO THE SIMPLE
PROPERTIES THAT GOVERN THE ATMOSPHERE. GIVEN A MID JULY PROFILE THAT
IS CLOUD FREE...TOGETHER WITH THE POTENTIAL FOR MECHANICAL
MIXING...HAVE VERY HIGH CONFIDENCE THAT AFTERNOON TEMPERATURES WILL
CLIMB INTO THE 90S ACROSS SOUTHWEST MINNESOTA.
ON SATURDAY CONFIDENCE IN TEMPERATURES DECREASES CONSIDERABLY AS A
FRONTAL BOUNDARY/TROUGH OF LOW PRESSURE STALLS OUT FROM SOUTHWEST TO
NORTHEAST OVER THE UPPER MIDWEST. THIS WILL INTRODUCE CHANCES FOR
SHOWERS AND THUNDERSTORMS...WHICH WILL GREATLY AFFECT AFTERNOON
HIGHS. THEREFORE DID NOT STRAY TOO MUCH FROM BLENDED GUIDANCE...AND
CONTINUE TO HAVE CHANCES FOR PRECIP INTO EARLY NEXT WEEK. THE BEST
CHANCE FOR RAIN...WITH 1-3 INCH AMOUNTS VERY LIKELY AT A FEW
LOCATIONS ACROSS THE NORTHWEST NEAR CANBY/ALEXANDRIA/ST CLOUD...WILL
BE LATE FRIDAY NIGHT INTO SATURDAY MORNING. LOOKING AHEAD...THE
THERMAL RIDGE WILL TAKE ON A POSITIVE TILT OVER THE UPPER
MISSISSIPPI RIVER VALLEY. ON SUNDAY THE ECMWF DRIVES A SHORTWAVE
ALONG THE US/CANADIAN BORDER THAT SUPPRESSES THE RIDGE...WHILE THE
GFS IS A DAY SLOWER WITH THIS FEATURE. ALSO...AS ALLUDED TO
EARLIER OVERCAST SKIES WILL GREATLY IMPACT HIGH TEMPS SO DID NOT
HAVE THE CONFIDENCE TO DEVIATE FROM A CONSENSUS APPROACH.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 700 AM CDT TUE JUL 9 2013
MATURE MCS WORKING ACROSS THE AIRSPACE THIS MORNING MOVING EAST AT
ABOUT 35 KTS HAS BEEN TIMED THROUGH TAFS TO START OUT THIS
MORNING. OTHER THAN A GUST TO 50 KTS AT RWF...ALL SITES TO THE
WEST HAVE BEEN TOPPING OUT AT 40 KTS ON GUSTS. HARD TO SAY WHAT
WILL HAPPEN THIS AFTERNOON AS THERE WILL BE A RECOVERY TIME FROM
MORNING STORMS. HRRR SEEMS A BIT QUICK WITH THE FRONT...BUT
SLOWING DOWN THE HRRR A BIT WOULD SUGGEST SCT TSRA POSSIBLE FROM
RWF TO STC EAST AFTER 20Z...BUT CONFIDENCE LOW ON THAT HAPPENING
NOW. WIND SPEEDS DO NOT PICK UP UNTIL YOU GET BEHIND THE FRONT AND
SHOULD GUST TO 20-25 KTS BEHIND THE FRONT FOR A COUPLE OF HOURS.
KMSP...TSRA STILL ON TARGET TO ARRIVE BETWEEN 1300 AND 1330Z AND
OUT AROUND 1530. EXPECT BRIEF GUSTS UP AROUND 40 MPH OUT OF THE
WEST...ALONG WITH BRIEF HEAVY DOWNPOURS. LOW CONFIDENCE ON WHAT
HAPPENS THIS AFTERNOON...BUT THERE IS THE POTENTIAL FOR MORE TSRA
BETWEEN 21Z AND 00Z BEFORE FRONT CLEARS EVERYTHING OUT AND ITS VFR
THE REST OF THE WAY.
/OUTLOOK FOR KMSP/
WED...VFR. WINDS NW 10G20KTS.
THU...VFR. WINDS LGT AND VRB.
FRI...VFR. WINDS S 10-15KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...JRB
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
412 AM CDT TUE JUL 9 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 410 AM CDT TUE JUL 9 2013
MAIN CONCERN IN THE SHORT TERM REVOLVES ON EVOLUTION OF STORMS
CURRENTLY ACROSS THE DAKOTAS THROUGH THE MORNING...FOLLOWED BY WHERE
THUNDERSTORMS REDEVELOP THIS AFTERNOON AND TRAVEL THIS EVENING. IT
IS THE AFTERNOON/EVENING ACTIVITY THAT WILL ALSO HAVE A SEVERE
THREAT. WIND AND HAIL WILL BE THE PRIMARY THREATS...THOUGH DEPENDING
ON WHERE BOUNDARIES ARE LEFT OVER FROM CONVECTION THIS
MORNING...THERE WILL ALSO BE THE SMALL CHANCE FOR TORNADOES ON ANY
LEFT OVER OUTFLOW BOUNDARIES.
AT 3 AM...WE WERE DEALING WITH A BIFURCATED LLJ IN TERMS OF MOISTURE
TRANSPORT MAXIMA...WITH ONE BRANCH DRIVING CONVECTION CURRENTLY
MOVING ACROSS THE DAKOTAS AND THE OTHER DRIVING ANOTHER CLUSTER
ALONG THE NEB/IA BORDER. THIS SRN BRANCH WILL TRACK ACROSS IA
THROUGH THE MORNING...KEEPING THAT CONVECTION SOUTH OF MN WHILE
BECOMING THE MAIN LLJ FOR POTENTIAL AFTERNOON ACTIVITY.
FOR THE MPX AREA...IT IS THE MCS THIS MORNING OVER SODAK THAT WILL
BE OUR PROBLEM. 3Z RAP MUCAPE ANALYSIS SHOWS A RIBBON OF 1000-1500
J/KG OF MUCAPE EXTENDING FROM THE MADISON/CANBY AREA...ESE TROUGH
ROCHESTER AND LA CROSSE. AS A RESULT...ANTICIPATE THIS BAND OF
THUNDERSTORMS WILL CONTINUE ESE ALONG THIS CAPE GRADIENT. AT ITS
CURRENT PACE...SHOULD ENTER WRN MN SHORTLY BEFORE 5 AM...REACH THE
I-35 CORRIDOR BETWEEN 7 AND 8 AM AND EVENTUALLY THE LSE/EAU AREAS BY
LATE MORNING. THE BULK OF THE CONVECTION WITH THIS LINE SHOULD TRACK
SOUTH OF I-94 THIS MORNING. AS FOR SEVERE THREAT...THE STRONG/SEVERE
LINE OF STORMS THAT MOVED ACROSS SODAK HAS NOW MERGED WITH THE WAA
ACTIVITY THAT HAD DEVELOPED OUT AHEAD OF IT...WITH ONE LINE NOW
EVIDENT ON REGIONAL RADAR ANALYSIS. WILL HAVE TO WATCH HOW THIS LINE
EVOLVES OVER THE NEXT HOUR TO SEE WHAT KIND OF SEVERE THREAT IT WILL
POSE. IN THE NEXT HOUR...IF IT BEGINS TO BOW OUT AND
ACCELERATE...THEN A WIND THREAT WILL EXIST THROUGH THE MORNING AS IT
TRACKS ACROSS MN. WITH THE RAP AT 3Z ANALYZING 20-30 KTS OF 0-3KM
SHEAR OUT AHEAD OF THE SYSTEM...IT IS PLAUSIBLE THAT THAT COULD
HAPPEN...THOUGH IN THE END IT MAY BE DIFFICULT TO GET ANY SEVERE
STRENGTH WINDS THROUGH THE STABLE BOUNDARY LAYER...SO AGREE WITH SPC
MCD THAT SEVERE THREAT WILL BE FAIRLY MARGINAL.
FOR THIS AFTERNOON...MANY A QUESTION MARKS STILL REMAIN IN PLACE.
THIS BIGGEST ISSUE IS HOW WILL STORMS THIS MORNING IMPACT WHAT
HAPPENS LATER. THE MAIN QUESTION IS DOES THE ATMOSPHERE HAVE ENOUGH
TIME TO RECHARGE FROM STORMS MOVING THROUGH LARGELY IN THE 10-18Z
TIME FRAME? FIRST WORD OF WARNING FOR THE ARM CHAIR FORECASTERS OUT
THERE...THE CAMS MAY NOT BE ALL THAT RELIABLE FOR WHAT HAPPENS LATER
THIS AFTERNOON AS ALL OF THEM ARE HANDLING CURRENT CONVECTION QUITE
POORLY /INCLUDING ALL MEMBERS OF THE 3Z HOPWRF/. PROBLEM
IS...OUTSIDE OF THE SPCWRF...NONE OF THE CAMS SNOW THUNDERSTORMS
MOVING ACROSS THE AREA OUTLINED IN THE PARAGRAPH ABOVE...MANY
/INCLUDING THE HOPWRF MEMBERS/ HAVE NOTHING MOVING ACROSS THE MPX
AREA THIS MORNING...SO HARD TO PUT MUCH STOCK IN WHAT THEY ARE DOING
THIS AFTERNOON. THE ONLY ONE TO BE SOMEWHAT CLOSE TO REALITY THIS
MORNING /SPCWRF/...SHOWS VERY LITTLE CONVECTION REDEVELOPING IN THE
MPX AREA THIS AFTERNOON.
CERTAINLY A BIG PLUS FOR THE AFTERNOON...IS OVER THE LAST 24
HOURS...MODELS HAVE SLOWED UP THE PROGRESSION OF THE FRONT ACROSS
THE MPX AREA...WHICH LIKELY EXPLAINS WHY HIGHER SEVERE PROBABILITIES
WERE PULLED NORTHWEST WITH THE DAY1 SPC CONVECTIVE OUTLOOK. CURRENT
MODEL BLEND WOULD SAY THE FRONT MOVES INTO THE NW MPX CWA AROUND
20Z...THE TWIN CITIES AROUND 00Z AND FINALLY CLEARS EAU AREA SHORTLY
AFTER 3Z. THIS PUTS THE FRONT ACROSS MUCH OF THE AREA DURING PEAK
HEATING...THOUGH IT IS STILL DEBATABLE HOW MUCH HEATING WE WILL SEE
BEHIND THE MORNING CONVECTION. IF CURRENT FORECAST WERE TO
HOLD...WITH TEMPERATURES REBOUNDING INTO THE MID 80S TO NEAR
90...WITH DEWPS IN THE LOWER 70S...THEN WE SHOULD HAVE NO PROBLEM
GENERATING 2000-3500 J/KG OF MLCAPE AHEAD OF THE BOUNDARY AS THE
NAM/GFS DO. FROM THE SHEAR PERSPECTIVE...A 40-60 KT MID LEVEL JET
MOVING IN WITH THE UPPER WAVE THIS AFTERNOON/EVENING WILL PROVIDE
PLENTY OF DEEP LAYER SHEAR TO SUPPORT UPDRAFT ROTATION AND STORM
ORGANIZATION...BUT THE 0-3KM SHEAR IS LOOKING MORE SUSPECT ACROSS
THE MPX AREA TO REALLY DRIVE UP A TORNADO THREAT. THE REASON FOR THE
POOR LOW LEVEL SHEAR IS THAT THE PRESSURE PATTERN AHEAD OF THE FRONT
WILL BE FAIRLY BAGGY...WITH LIGHT PREFRONTAL WINDS EXPECTED. IN
ADDITION...THE CORE OF A 30-40 KT LLJ WILL EXTEND FROM CENTRAL IA
TOWARD NE WIS...STAYING JUST SE OF THE MPX AREA. COMBINED...THE WEAK
SFC WINDS AND BETTER LLJ BEING JUST SE OF THE MPX CWA RESULT IN
MARGINAL 0-1 KM AND 0-3 KM SHEAR /MAINLY 20 KTS OR LESS/. BESIDE THE
WEAKER SHEAR...THE WEAK SFC WINDS OUT AHEAD OF THE FRONT WILL ALSO
LIMIT THE AMOUNT OF CONVERGENCE ALONG IT...WHICH MAY HELP EXPLAIN
WHY MANY OF THE CAMS /OUTSIDE OF THE 3Z HOPWRF/ STRUGGLE TO GENERATE
MUCH CONVECTION ALONG THE BOUNDARY THIS AFTERNOON.
IN SUMMARY...CONFIDENCE IS HIGH THAT MCS CURRENTLY OVER ERN SODAK
WILL TRACK ACROSS AREAS SOUTH OF I-94 THIS MORNING. BECAUSE OF
THIS...CONFIDENCE IN HOW THE AFTERNOON PLAYS OUT IS CONSIDERABLY
DIMINISHED. BUT...GIVEN FRONTAL TIMING...EXPECT AT LEAST SCT STORMS
TO DEVELOP ALONG THE FRONT BETWEEN 19Z AND 21Z THAT WILL THEN TRACK
SE THIS EVENING WITH THE FRONT. GIVEN DEGREE OF INSTABILITY AND BULK
SHEAR...LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY THREAT.
THE WEAKER LOW LEVEL SHEAR MEANS THAT UNLESS A STORM CAN LATCH ON TO
A REMNANT OUTFLOW BOUNDARY...THE TORNADO THREAT APPEARS TO BE
RELATIVELY LOW...THOUGH NOT NEGLIGIBLE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 410 AM CDT TUE JUL 9 2013
THE FIRST HALF OF THE PERIOD WILL START OFF DRY AS LARGE SCALE
SUBSIDENCE DOWNSTREAM OF THE UPPER LEVEL RIDGE AXIS BUILDS AN AREA
OF SURFACE HIGH PRESSURE ACROSS THE UPPER MIDWEST. FORECAST
SOUNDINGS SHOW A DRY PROFILE WITH PWATS ONLY AROUND 0.75
INCHES...ALONG WITH LITTLE POTENTIAL FOR CLOUDS DURING THE DAY ON
WEDNESDAY. WINDS WILL GO CALM OVERNIGHT ALLOWING AN INVERSION TO SET
UP AND TEMPERATURES TO COOL DOWN TO THE UPPER 50S ACROSS MOST
LOCATIONS...WITH LOW 60S EXPECTED IN AND AROUND THE METRO DO TO THE
HEAT ISLAND. THURSDAY WILL BE DRY AS WELL WITH THE SURFACE HIGH
STILL SUPPRESSING ANY CHANCE OF PRECIP. BY THURSDAY NIGHT THE SURFACE
HIGH WILL DRIFT EASTWARD AS THE THERMAL RIDGE APPROACHES FROM THE
WEST...AND SOUTHERLY WINDS ON THE BACK SIDE WILL KEEP OVERNIGHT LOWS
IN THE MID TO UPPER 60S ACROSS WESTERN MINNESOTA. FRIDAY SHOULD BE
MUCH WARMER THAN CURRENTLY FORECAST BY THE NUMERICAL MODELS. BOTH
THE GFS AND ECMWF 09.00 HAVE H850 TEMPS 20-22C...WITH SOUTHERLY
WINDS OF 30KTS...YET FOR SOME REASON THE FORECAST SOUNDINGS ONLY
SHOW MIXING UP TO AROUND 900MB. THIS IS CONTRADICTORY TO THE SIMPLE
PROPERTIES THAT GOVERN THE ATMOSPHERE. GIVEN A MID JULY PROFILE THAT
IS CLOUD FREE...TOGETHER WITH THE POTENTIAL FOR MECHANICAL
MIXING...HAVE VERY HIGH CONFIDENCE THAT AFTERNOON TEMPERATURES WILL
CLIMB INTO THE 90S ACROSS SOUTHWEST MINNESOTA.
ON SATURDAY CONFIDENCE IN TEMPERATURES DECREASES CONSIDERABLY AS A
FRONTAL BOUNDARY/TROUGH OF LOW PRESSURE STALLS OUT FROM SOUTHWEST TO
NORTHEAST OVER THE UPPER MIDWEST. THIS WILL INTRODUCE CHANCES FOR
SHOWERS AND THUNDERSTORMS...WHICH WILL GREATLY AFFECT AFTERNOON
HIGHS. THEREFORE DID NOT STRAY TOO MUCH FROM BLENDED GUIDANCE...AND
CONTINUE TO HAVE CHANCES FOR PRECIP INTO EARLY NEXT WEEK. THE BEST
CHANCE FOR RAIN...WITH 1-3 INCH AMOUNTS VERY LIKELY AT A FEW
LOCATIONS ACROSS THE NORTHWEST NEAR CANBY/ALEXANDRIA/ST CLOUD...WILL
BE LATE FRIDAY NIGHT INTO SATURDAY MORNING. LOOKING AHEAD...THE
THERMAL RIDGE WILL TAKE ON A POSITIVE TILT OVER THE UPPER
MISSISSIPPI RIVER VALLEY. ON SUNDAY THE ECMWF DRIVES A SHORTWAVE
ALONG THE US/CANADIAN BORDER THAT SUPPRESSES THE RIDGE...WHILE THE
GFS IS A DAY SLOWER WITH THIS FEATURE. ALSO...AS ALLUDED TO
EARLIER OVERCAST SKIES WILL GREATLY IMPACT HIGH TEMPS SO DID NOT
HAVE THE CONFIDENCE TO DEVIATE FROM A CONSENSUS APPROACH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY MORNING)
ISSUEDAT 1002 PM CDT MON JUL 8 2013
CONVECTION CONTINUES TO INCREASE ACROSS THE DAKOTAS LATE THIS
EVENING. SHORT TERM PROJECTIONS SHOW SCT SHRA/TSRA POTENTIALLY
REACHING KAXN AND KRWF BY 08Z...KSTC BY 10Z AND THE TWIN CITIES BY
12Z. ADJUSTED TIMES IN THE CURRENT TAF PACKAGE TO REFLECT THIS.
THERE REMAINS THE THREAT OF FOG OVERNIGHT...FROM KSTC TO KEAU. THE
INCREASE IN CLOUDS AND THE THREAT OF SHOWERS SHOULD LIMIT HOW LOW
THE VSBY DROPS AT KSTC AND KRNH. KEAU REMAINS THE PRIME LOCATION
FOR IFR OR LOWER BR/FG BETWEEN 09Z AND 12Z. SHOWERS AND A FEW
THUNDERSTORMS SHOULD MOVE ACROSS KRNH AND KEAU TUESDAY MORNING.
MORE ACTIVITY WILL DEVELOP AHEAD OF AN APPROACHING COLD FRONT
TUESDAY AFTERNOON. THIS SHOULD START EARLY IN THE AFTERNOON AROUND
KAXN...KRWF AND KSTC AND REACH THE TWIN CITIES AN WESTERN WI BY
LATE AFTERNOON/EARLY EVENING. INCREASING NW WINDS OF 10 TO 20
KNOTS IN THE WAKE OF THE FRONT FOR TUESDAY NIGHT.
KMSP...
SCT SHRA/TSRA EXPECTED TO PUSH THROUGH THE TWIN CITIES IN THE
12Z-15Z TIME FRAME WITH LINGERING SHOWERS THROUGH THE LATE
MORNING HOURS. A COLD FRONT WILL APPROACHING FROM THE WEST DURING
THE LATE AFTERNOON (21Z). MORE SHRA/TSRA EXPECTED ALONG AND AHEAD
OF THE FRONT WITH FRONTAL PASSAGE STILL LOOKING TO BE AROUND 01Z.
INCREASING NW WINDS OF 15-20 KNOTS BY LATE EVENING AND CONTINUING
OVERNIGHT.
/OUTLOOK FOR KMSP/
WED...VFR. WINDS NW 10G20KTS.
THU...VFR. WINDS LGT AND VRB.
FRI...VFR. WINDS S 10-15KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...JRB
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
415 PM CDT Tue Jul 9 2013
.SHORT TERM...(This Evening through Wednesday Night)
Issued at 414 PM CDT TUE JUL 9 2013
Tonight - The primary concern for the next 15 hours centers on rain
chances and coverage. A very hot and humid airmass covers the CWA
with the hot air extending to at least h7. While the latest progged
thermodynamics indicate a very unstable airmass over the region
with little if any CIN the lack of cumulus development suggests two
things...the convective temperature has not been reached and the
progged h7 temperatures are warmer than forecast. The models had
forecast cooling h7 temperatures by this time over parts of northern
MO in response to convection already in progress. While convection
has not reformed the latest visible satellite imagery does show a
growing cumulus filed from central into southwest IA near an weak
surface trough which extends into central KS. This boundary is the
most likely area to focus on for scattered convective development
late this afternoon and early evening. Will continue with 40-50%
PoPs north of I-70 overnight. Given steep lapse rates through h7,
MLCAPES of 3000-4000 J/kg, 30-40kt 0-6km bulk shear and high cloud
bases large hail and damaging downburst winds will be possible
through this evening. Should convection become organized
sufficiently a decent cold pool could allow for a small MCS to form
which would prolong the severe wind threat.
Otherwise, a weak cold front over northern IA will sink southward
overnight but the cooling effect will lag the frontal passage so
warm and humid conditions will persist.
Wednesday and Wednesday night - High pressure will gradually push
the cold front far enough south on Wednesday to allow some relief
from Tuesday`s heat...with northern MO receiving the most benefit as
drier air will also accompany the northeasterly winds.
Upper troughing developing from the Great Lakes into the OH Valley
and the upper high building northward over the Rockies will create a
northwesterly flow pattern over the Central Plains. This causes me
some concern for afternoon/evening convection over parts of the
western CWA as the GFS and NAM both send a mid level vorticity max
out of eastern WY/western NE towards western MO. With this in mind
have inserted chance PoPs into the far southwestern counties for the
late afternoon and early evening hours.
While temperatures will be cooler on Wednesday we won`t see the full
effects of the cooler/drier air until Wednesday night and Thursday.
.LONG TERM...(Thursday through Tuesday)
Issued at 414 PM CDT TUE JUL 9 2013
Thursday should be the coolest day of the extended period before an
expansive dome of high pressure builds over the central CONUS. As the
ridge develops and becomes parked over the region, temperatures will
steadily warm into the lower 90s across eastern KS and western MO
with upper 80s across the far northeast portion of the CWA. With the
ridge in place precip chances should be nil through Tuesday as any
weak disturbance moving around the periphery of the ridge remains
well to our north. The pattern appears to continue well through next
week as the GFS and EC depict little movement of the upper level
ridge.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday Afternoon)
Issued at 1250 PM CDT TUE JUL 9 2013
Timing of organized convection is the primary challenge. A weak
surface trough across northern KS into northwest MO appears to be one
boundary may act to focus scattered convection late this afternoon and
evening. Satellite imagery shows accas field stretching from central
KS through west central MO with some convection noted over central
KS. Short range models RAP and HRRR plus the 12z NAM/GFS seem to be
picking up on this area of convection and develop/move scattered convection
into the terminals late this afternoon or early evening. Believe
there is enough support an earlier start time for VCTS with best
threat a few hours either side of sunset. Due to the hot mid level
temperatures VFR ceilings will prevail which also increases the
threat for strong/gusty winds in any of the stronger storms. Will
address this in an amendment once storms organize.
Will keep VCTS until frontal passage which occurs during the pre-dawn
hours of Wednesday morning.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...HEAT ADVISORY until 7 PM CDT this evening FOR KSZ025-057-060-
102>105.
MO...HEAT ADVISORY until 7 PM CDT this evening FOR MOZ001>005-011>014-
020>023-028>031-037>039-043>045-053-054.
&&
$$
SHORT TERM...MJ
LONG TERM...Pietrycha
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1252 PM CDT Tue Jul 9 2013
.SHORT TERM...(Today and Tonight)
Issued at 358 AM CDT TUE JUL 9 2013
Early this morning a shortwave trough, moving east along the
U.S/Canadian border, has induced yet another modest nocturnal jet
across the Plains States. This has helped fuel the development of
thunderstorms across eastern Nebraska and western Iowa early this
morning. Active storms are on the verge of entering the far
northwest corner of Missouri early this morning, and are expected to
make some progress east across northern Missouri before the jet
fueling this activity veers off and mixes out after sunrise. Storms
are not expected to develop much farther south than Highway 36 owing
to the CAP advecting in on the nocturnal jet, 700mb temperatures >
12C. Radar trends back this up, but will have to keep a careful eye
on this this morning.
Once the vestiges of the early morning storms dissipate, the heating
for the day will kick into high gear. The hot air that advected in
with the CAP will begin to mix down later today allowing
temperatures to range a category or more higher than Monday. With
850mb temperatures expected to top out in the 25C to 28C range,
expect surface temperatures to bound into the mid to upper 90s along
the Kansas-Missouri state border. While some dry air will likely mix
down this afternoon, taking a slight edge off the humidity, it is
not expected to mitigate heat indices enough to prevent index values
from ranging around 105 degrees by this afternoon. Will be leaving
the going heat advisory as is.
By tonight a frontal boundary across Nebraska and Iowa will begin
its southward progress into Kansas and Missouri as the parent
shortwave trough along the Canadian border moves east. Expectations
are that convection will initiate across Nebraska and Iowa this
afternoon, traversing southeast along with the front. There are some
concerns that a weak outflow boundary from the early morning
activity may wallow around northern Missouri today --maybe as far
south as the Missouri River-- which might provide some focus for
storms to initiate on during the mid to late afternoon hours. Do not
think this is overly likely, but cannot rule it out, so have kept
slight chance POPs going for the afternoon hours. Baring early
initiation across Missouri, expectations are that the activity in
Nebraska and Iowa will track southeast into eastern Kansas and
Missouri this evening. Sufficient shear and instability look to be in
place tonight to warrant a threat from some severe weather, with
damaging wind gusts looking to be the primary threat.
Wednesday...the front that moved into Tuesday night will finish its
progress across our section of the state. Other than any lingering
activity in the morning hours, expect storms to be focused in area
to the south and east of our region by the afternoon hours.
Additionally, the northerly wind behind the front will bring
slightly cooler and drier conditions, think mid-80s along the Iowa
border to low 90s in east central Kansas.
.LONG TERM...(Wednesday through Monday)
Issued at 358 AM CDT TUE JUL 9 2013
Behind Wednesday`s front, high pressure will settle in from the
north for Wednesday night and Thursday, keeping temperatures
relatively lower with lows Weds night in the lower 60s and highs on
Thursday in the mid 80s. This relief from the heat will be
short-lived as upper ridging will quickly build back into the
central U.S. through the end of the week into early next week. Highs
through this period will return into the 90s for western MO and
eastern KS and upper 80s further northeast. Judging by the depth of
the upper ridge, these numbers may need to be adjusted upward with
later forecasts.
Rain chances through the extended period appear low thanks to the
large upper ridge in place. Models are hinting at weak warm air
advection precipitation across eastern KS Wednesday night or
Thursday, but moisture/thermal profiles to not appear supportive of
this. Only other chance appears to be on Monday as the ridge
flattens a bit, but better rain chances will remain well to the
north of the area.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday Afternoon)
Issued at 1250 PM CDT TUE JUL 9 2013
Timing of organized convection is the primary challenge. A weak
surface trough across northern KS into northwest MO appears to be one
boundary may act to focus scattered convection late this afternoon and
evening. Satellite imagery shows accas field stretching from central
KS through west central MO with some convection noted over central
KS. Short range models RAP and HRRR plus the 12z NAM/GFS seem to be
picking up on this area of convection and develop/move scattered convection
into the terminals late this afternoon or early evening. Believe
there is enough support an earlier start time for VCTS with best
threat a few hours either side of sunset. Due to the hot mid level
temperatures VFR ceilings will prevail which also increases the
threat for strong/gusty winds in any of the stronger storms. Will
address this in an amendment once storms organize.
Will keep VCTS until frontal passage which occurs during the pre-dawn
hours of Wednesday morning.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...HEAT ADVISORY until 7 PM CDT this evening FOR KSZ025-057-060-
102>105.
MO...HEAT ADVISORY until 7 PM CDT this evening FOR MOZ001>005-011>014-
020>023-028>031-037>039-043>045-053-054.
&&
$$
SHORT TERM...Cutter
LONG TERM...Hawblitzel
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
313 PM CDT TUE JUL 9 2013
.DISCUSSION...
THUNDERSTORM CHANCES TONIGHT AND POSSIBLY WEDNESDAY NIGHT...THEN
HEAT POTENTIAL INTO NEXT WEEK...ARE THE PRIMARY FORECAST CONCERNS.
UPPER RIDGE WAS SPRAWLING ACROSS THE SOUTH HALF OF THE CONUS
TODAY...WITH OUR AREA IN THE TRANSITION ZONE BETWEEN RIDGE TO THE
SOUTH AND FASTER MID LEVEL FLOW TO THE NORTH. A POTENT SHORTWAVE WAS
NOTED IN NORTH DAKOTA SWEEPING EAST THIS AFTERNOON...AND WILL SETTLE
INTO THE GREAT LAKES WEDNESDAY AFTERNOON BEFORE CARVING OUT A TROUGH
OVER NEW ENGLAND BY SATURDAY. SHORTWAVE WILL DRIVE A COLD FRONT
SOUTH OF OUR AREA TONIGHT AND WEDNESDAY...THEN ALLOW UPPER RIDGE TO
BUILD INTO THE PLAINS THIS WEEKEND INTO NEXT WEEK.
EARLY AFTERNOON SURFACE ANALYSIS SHOWED A WIND SHIFT SETTLING SOUTH
TOWARD A COLUMBUS TO TEKAMAH LINE...WITH A SECONDARY BOUNDARY MOVING
OUT OF SOUTH DAKOTA INTO NORTHEAST NEBRASKA. AIRMASS BEHIND THIS
SECOND BOUNDARY WAS CHARACTERIZED BY DEW POINTS IN THE 60S AND
TEMPERATURES CLOSER TO 80. SOUTH OF BOTH BOUNDARIES...TEMPERATURES
WERE CLIMBING INTO THE 90S WITH DEW POINTS IN THE LOW TO MID
70S...PUTTING HEAT INDICES INTO THE 100S AT MANY SPOTS. WILL
MAINTAIN OUR CURRENT HEAT ADVISORY INTO THE EARLY EVENING...AND MAY
TRIM SOME NORTHERN COUNTIES BASED ON OBS.
INSTABILITY WAS ALSO INCREASING MARKEDLY ACROSS SOUTHEAST NEBRASKA
AND SOUTHWEST IOWA WHERE SURFACE-BASED CAPES WERE WELL OVER 3000
J/KG ACCORDING TO LATEST RAP ANALYSIS. HOWEVER FORECAST SOUNDINGS
SHOW A SIGNIFICANT WARM NOSE ABOVE SURFACE LAYER WAS CAPPING ANY
ATTEMPT AT CONVECTION SO FAR. AS FRONTAL BOUNDARY SETTLES INTO
SOUTHEAST NEBRASKA AND SOUTHWEST IOWA THIS EVENING...COMBINED WITH A
LITTLE MORE HEATING AND A WEAK IMPULSE SLIDING ACROSS NORTHERN
KANSAS...EXPECT SCATTERED THUNDERSTORMS TO FIRE IN OUR SOUTHERN
CWA...MOST LIKELY SOUTH OF INTERSTATE 80. IF THOSE DO OCCUR...AMOUNT
OF INSTABILITY AND MODEST BULK SHEAR NEAR 35KT SUGGEST SEVERE STORMS
ARE POSSIBLE WITH DAMAGING WINDS THE MOST LIKELY HAZARD. FREEZING
LEVELS REMAIN QUITE HIGH...IN THE NEIGHBORHOOD OF 14KFT TO
15KFT...SO ONLY STORMS WITH DECENT STRUCTURE/ROTATION SHOULD POSE
HAIL THREAT.
ACTIVITY SHOULD SHIFT SOUTH OF OUR AREA A LITTLE AFTER 06Z TONIGHT
AS FRONT SETTLES SOUTH...LEAVING THE REST OF THE NIGHT DRY. WITH
LOWER DEW POINTS SPILLING INTO THE AREA COMBINED WITH LIGHT
NORTHERLY WINDS...EXPECT LOWS TO DROP INTO THE LOWER 60S NORTH BUT
HOLD IN THE LOWER 70S SOUTH.
A SOMEWHAT COOLER AND DRIER COUPLE OF DAYS STILL LOOKS ON TRACK FOR
WEDNESDAY AND THURSDAY AS DEW POINTS DROP CLOSER TO 60 THAN 70.
HIGHS EACH DAY SHOULD HOLD IN THE MIDDLE 80S OR SO. HOWEVER SOUTH
WINDS WILL RETURN FOR THURSDAY...SO AN INCREASE IN LOW LEVEL
MOISTURE WILL BEGIN THEN. THERE IS ALSO A SMALL CHANCE FOR
THUNDERSTORMS WEDNESDAY NIGHT INTO THURSDAY MORNING...ESPECIALLY
OVER OUR FAR SOUTHWEST CWA AND CENTRAL NEBRASKA...WHERE ZONE OF MID
LEVEL WARM ADVECTION COULD TRIGGER ELEVATED STORMS.
RIDGE BEGINS TO BUILD INTO THE REGION ON FRIDAY AND REMAINS OVER THE
MIDDLE OF THE COUNTRY THROUGH NEXT WEEK. THIS SHOULD NORMALLY KEEP
US DRY AND HOT...BUT ECMWF AND TO SOME EXTENT THE GFS SHOW A
WEAKNESS IN THE RIDGE SUNDAY AND MONDAY THAT MAY ALLOW A SURFACE
FRONT TO DRIFT INTO OUR AREA. CURRENTLY HAVE SMALL POPS DURING THIS
TIME PERIOD...SO WILL NOT CHANGE AT THIS TIME. OTHERWISE EXPECT
TEMPERATURES TO APPROACH OR EXCEED 90 MUCH OF THE PERIOD FRIDAY
THROUGH TUESDAY.
DERGAN
&&
.AVIATION...18Z TAFS FOR KOFK...KLNK AND KOMA.
QUIET WEATHER SHOULD DOMINATE DURING MOST OF THE TAF PERIOD WITH VFR
CONDITIONS...FEW CLOUDS...AND LIGHT WINDS. A WEAK COLD FRONT WILL
SLOWLY MOVE THROUGH THE REGION THIS EVENING CAUSING WINDS TO SHIFT
TO THE NORTH. THE FRONT MAY TRIGGER ISOLATED THUNDERSTORMS OVER
SOUTHERN NEBRASKA THIS EVENING...BUT ANY STORMS THAT DEVELOP SHOULD
REMAIN SOUTH OF KOMA AND KLNK.
DENSITY ALTITUDE WILL BE NOTABLY HIGH GIVEN THE HOT AND HUMID
AIRMASS IN PLACE THIS AFTERNOON.
NIETFELD
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NEZ045-052-053-067-
068-088>093.
IA...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR IAZ055-056-069-079-
080-090-091.
&&
$$
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1255 AM CDT TUE JUL 9 2013
.UPDATE...
ISSUED AT 1255 AM CDT TUE JUL 9 2013
LLJ-DRIVEN SHWRS/TSTMS AND THEIR REMNANTS CONTINUE MOVING E AT 26
KTS. THEIR HIGH-BASED NATURE IS LIMITING RFALL AMTS TO AROUND .1"
WITH UP TO .2" FOR THE LUCKIEST SPOTS. NOT EXPECTING ANY SVR BUT
WE WILL NEED TO KEEP AN EYE FOR HEAT BURST ACTIVITY...PRIMARILY
OVER N-CNTRL KS WHERE PCPN COVERAGE IS LEAST BUT THE INVERTED-V
THERMODYNAMIC PROFILE IS PRESENT.
THE MOST SHORT-TERM ADJUSTMENTS WERE TO BEST RECONFIGURE POPS
BASED ON 88D TRENDS AND WE WILL PROBABLY NEED TO MAKE FURTHER
ADJUSTMENTS AS THE NGT WEARS ON. OTHERWISE...LOW TEMPS APPEAR ON
TRACK.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 455 PM CDT MON JUL 8 2013
PLENTY OF THINGS TO PONDER DURING THE NEXT 24 HOURS...INCLUDING AT
LEAST ONE CONDITIONAL RISK FOR SEVERE STORMS THIS EVENING...AND
MAYBE ANOTHER SEVERE RISK ON TUESDAY AFTERNOON/EVENING...ALTHOUGH
CONFIDENCE IS QUITE LOW ON THE LIKELIHOOD/EVOLUTION OF THE LATTER.
IN OTHER DEPARTMENTS...TOMORROW IS CURRENTLY EXPECTED TO BE THE
OVERALL-HOTTEST AFTERNOON OF THE SUMMER SO FAR FOR MOST OF THE
CWA...AND A HEAT ADVISORY HAS BEEN ISSUES FOR SEVERAL
SOUTHERN/SOUTHEAST COUNTIES.
21Z OBJECTIVE SURFACE ANALYSIS HIGHLIGHTS A SOMEWHAT SUBTLE-BUT
EVIDENT EAST-WEST QUASI STATIONARY GENERALLY STRETCHED ACROSS THE
SOUTHERN HALF OF NEBRASKA. IN THE WIND-FIELD...THIS BOUNDARY
SEPARATES A STEADY 15+ MPH SOUTHERLY BREEZE IN NORTH CENTRAL
KANSAS...FORM A LIGHTER...GENERALLY EAST-SOUTHEAST BREEZE WITHIN
MOST OF THE NEBRASKA CWA. ITS ALSO SOMEWHAT OF A MOISTURE
BOUNDARY...WITH MID-50S TO LOW 60S DEWPOINTS RESIDING IN THE
DEEPLY MIXED AIRMASS TO THE SOUTH...AND HIGHER DEWPOINTS MID-60S
TO NEAR 70 MOST AREAS ALONG/NORTH OF I-80. AS DISCUSSED EARLIER
TODAY...NEAR-CRITICAL FIRE DANGER WILL PERSIST FOR A FEW MORE
HOURS ESPECIALLY IN THE PHILLIPS/ROOKS COUNTY AREA IN KS. HIGH
TEMPS THIS AFTERNOON WORKED OUT PRETTY WELL ACROSS THE
SOUTHWESTERN 2/3 OF THE CWA RANGING GENERALLY 95-104
DEGREES...WHILE SOME NORTHEAST AREAS ARE STRUGGLING TO REACH 90
THANKS IN PART TO A BATCH OF MID LEVEL CLOUDS THAT FORMED ON THE
BACK-SIDE OF AN MCV THAT HAS MOVED WELL EAST INTO WESTERN IA.
ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA CONFIRM
CONTINUED QUASI-ZONAL FLOW ACROSS THE LOCAL AREA...BETWEEN THE
LARGER-SCALE MID LEVEL RIDGE AXIS STRETCHED WEST-EAST FROM AZ TO
OK...AND A VIGOROUS SHORTWAVE TROUGH MAKING ITS WAY ACROSS THE
ID/MT/CANADA BORDER AREA. THE MAIN LOW-AMPLITUDE SHORTWAVE TROUGH
OF INTEREST FOR THIS EVENING IS CURRENTLY LIFTING OUT OF WY INTO
WESTERN NEB/SD.
LATE THIS AFTERNOON INTO THIS EVENING...THE PRIMARY FOCUS IS ON
HOW MUCH THUNDERSTORM COVERAGE THE CWA WILL SEE...AND WHETHER SOME
OF THIS ACTIVITY COULD BECOME SEVERE. AT PRESENT TIME...RADAR
INDICATES A FEW WEAK-ISH/HIGH-BASED STORMS NEAR THE STATE LINE IN
THE SOUTHWESTERN CWA...LARGELY A RESULT OF VERY STEEP LOW-LEVEL
LAPSE RATES IN THE HOT/DEEPLY MIXED AIRMASS OVER KS.
MEANWHILE...OFF TO THE NORTHWEST...A FEW STRONG TO SEVERE STORMS
HAVE TAKEN OFF IN NORTH CENTRAL/WESTERN NEB...IN AN ENVIRONMENT
CHARACTERIZED BY AROUND 2000+ J/KG MLCAPE AND 30+ KNOTS OF 0-6KM
DEEP LAYER SHEAR. LOCALLY...WITH THE EXCEPTION OF THE HIGH-BASED
STORMS IN OUR SOUTH...MODEL SOUNDINGS SUGGEST THERE IS JUST ENOUGH
OF A CAP IN PLACE TO KEEP CONVECTION FROM DEVELOPING OVERHEAD IN
MOST OF THE CENTRAL/NORTHERN CWA...AIDED IN PART BY SUBSIDENCE
BEHIND THE DEPARTING MCV. AS HAS BEEN THE CASE FOR DAYS
NOW...CONFIDENCE IN THE DETAILS IS LOW IN THIS WEAKLY FORCED
PATTERN...BUT TAKING CUE FROM THE LATEST RAP/HRRR AND 12Z 4KM WRF-
NMM...THE GENERAL EXPECTATION IS FOR MOST OF THE CWA TO REMAIN
STORM FREE THROUGH AT LEAST 00Z/7PM...BEFORE STORM CHANCES
GRADUALLY INCREASE THROUGH THE EVENING HOURS ESPECIALLY NEAR/NORTH
OF I-80...AND LIKELY MAINLY AS A FUNCTION OF ACTIVITY MOVING IN
FROM WESTERN NEBRASKA...ALTHOUGH LOCAL INITIATION NEAR THE SURFACE
BOUNDARY CANNOT BE RULED OUT EITHER. BOTH THE WRF-NMM AND HRRR ARE
FAIRLY AGGRESSIVE BRINGING A CLUSTER OF STORMS...POSSIBLY A SEMI-
ORGANIZED MCS ACROSS ESPECIALLY THE NORTHERN 1/2 OF THE CWA THIS
EVENING...BUT A SIMILAR MODEL DEPICTION YESTERDAY ENDED UP BEING A
BIT OVERDONE...AND THUS HAVE CAPPED POPS AT NO HIGHER THAN 50
PERCENT AT LEAST FOR NOW. WITH MLCAPE REMAINING 1000+ J/KG WELL
INTO THE EVENING HOURS AND WITH AT LEAST MODEST SHEAR...AT LEAST A
LOCALIZED LARGE HAIL AND ESPECIALLY A WIND THREAT IS QUITE
POSSIBLE ESPECIALLY IF STORMS TO THE WEST CAN ORGANIZE AND DEVELOP
A COLD POOL. AGREE WITH SPC IN HIGHLIGHTING THE NORTHERN 1/2 OF
THE CWA FOR THE GREATEST SEVERE THREAT...BUT JUST CANNOT RULE OUT
A STRONG TO SEVERE STORM ANYWHERE IN THE CWA THIS EVENING.
ALTHOUGH THE MAIN SEVERE THREAT SHOULD BE ON THE WANE BY
MIDNIGHT...LINGERED LOW POPS THROUGH THE NIGHT ESPECIALLY ACROSS
THE EASTERN 2/3 OF THE CWA TO ACCOUNT FOR ACTIVITY PERSISTING OR
NEWLY-DEVELOPING WITHIN THE LOW LEVEL JET AXIS...AND JUST AHEAD ON
APPROACHING COLD FRONT. IF NOTHING ELSE...HOPEFULLY PARTS OF THE
CWA CAN RECEIVE SOME MUCH-NEEDED RAINS TONIGHT...BECAUSE THIS MAY
BE ONE OF THE BETTER CHANCES FOR AWHILE. TEMPERATURE-WISE...MADE
ONLY MINOR TWEAKS TO LOWS...WITH THE PREVALENT LIGHT SOUTHERLY
BREEZE HOLDING MOST AREAS UP INTO THE 70-75 RANGE. ALTHOUGH AT
LEAST LIGHT FOG DEVELOPMENT CANNOT BE RULED OUT LATE TONIGHT
ESPECIALLY IN AREAS THAT RECEIVE RAIN...THE PROBABILITY/MAGNITUDE
SEEMED LOW ENOUGH TO OMIT FROM THE FORECAST.
TURNING TO TUESDAY DAYTIME...REALLY DON/T THINK SEVERE STORMS ARE
GOING TO END UP BEING MUCH OF A STORY...AT LEAST THROUGH THE VAST
MAJORITY OF THE DAY. ALOFT...QUASI-ZONAL FLOW WILL START TO TURN A
BIT MORE NORTHWESTERLY IN RESPONSE TO THE PASSAGE OF A FAIRLY
VIGOROUS SHORTWAVE TROUGH FROM EASTERN MT TOWARD NORTHERN MN. AT
THE SURFACE...A FAIRLY WEAK COLD FRONT...MORE EVIDENT IN THE WIND
FIELD THAN ON A THERMOMETER...WILL WORK SOUTHWARD ACROSS THE CWA
AS THE DAY WEARS ON...WITH MOST AREAS SEEING A FEW HOURS OF
LIGHT/VARIABLE WINDS BEFORE A SLIGHTLY MORE STEADY NORTHERLY
BREEZE SETTLES IN. ALONG AND ESPECIALLY JUST AHEAD OF THIS
BOUNDARY...A LOW LEVEL THERMAL RIDGE WILL EXTEND INTO THE CWA FROM
THE SOUTHWEST...PROMOTING WHAT SHOULD BE THE HIGHEST HEAT-INDEX
READINGS OF THE SUMMER SO FAR FOR MOST ALL OF THE CWA...AND IN
SOME SPOTS THE HOTTEST ACTUAL AIR TEMPERATURES. THE ONLY CAVEATS
WOULD BE AN UNEXPECTEDLY STRONG OUTFLOW BOUNDARY FROM CONVECTION
TONIGHT THAT MIGHT HELP ACCELERATE THE COLD FRONT SOUTHWARD
FASTER...AND MAYBE A DENSER-THAN-EXPECTED COVERAGE OF MID LEVEL
CLOUDS OR LINGERING WEAK CONVECTION. BUT ASSUMING NEITHER ONE OF
THESE CAVEATS PLAY OUT...HAVE AIMED FOR ACTUAL HIGH TEMPS RANGING
FROM MID 90S NORTH...UPPER 90S CENTRAL...AND 100-106 NEAR AND
SOUTH OF THE STATE LINE. HEAT INDEX VALUES OF 100+ ARE FORECAST
ACROSS MUCH OF THE SOUTHERN AND EASTERN HALVES OF THE CWA...AND
HAVE ISSUED A HEAT ADVISORY FOR ALL KS ZONES ALONG WITH WEBSTER-
NUCKOLLS-THAYER IN NEBRASKA...WHICH HAVE THE HIGHEST LIKELIHOOD OF
REACHING OR EXCEEDING A 105 HEAT INDEX. FORTUNATELY FOR FIRE
WEATHER CONCERNS IN THE FAR SOUTHWEST COUNTIES...SUSTAINED
WINDS/GUSTS DO NOT LOOK TO EXCEED 20 MPH DURING THE PEAK OF
AFTERNOON HEATING. AS FOR CONVECTIVE CHANCES...FORECAST SOUNDINGS
SUGGEST THAT A FAIRLY STRONG CAP SHOULD PREVAIL THROUGH THE DAY AS
VERY WARM MID LEVEL TEMPS OVERSPREAD THE AREA. AS A RESULT...OTHER
THAN A LINGERING SLIGHT CHANCE OF MORNING STORMS IN EASTERN
COUNTIES RIGHT AWAY IN THE MORNING...WILL AIM FOR A DRY MAJORITY
OF THE DAY...BEFORE BRINGING BACK SLIGHT STORM CHANCES POST-
21Z/4PM. THERE ARE AT LEAST TWO POSSIBLE FOCUSES FOR LATE
AFTERNOON DEVELOPMENT...THE MAIN COLD FRONT WHICH SHOULD BE VERY
NEAR THE FAR SOUTHEAST CORNER OF THE CWA...AND ALSO FORCING FROM
THE SOUTHERN EDGE OF THE NORTHERN PLAINS SHORTWAVE TROUGH...WHICH
COULD KICK OFF CONVECTION CLOSER TO THE NORTHERN EDGE OF THE CWA.
HOWEVER...MODELS SUCH AS THE 12Z 4KM WRF-NMM ADVERTISE ESSENTIALLY
NO LATE AFTERNOON STORMS ANYWHERE IN THE CWA...SO THUS ONLY THE
SLIGHT POPS. IF STORMS WOULD MANAGE TO FORM...A CONDITIONAL SEVERE
THREAT COULD EXIST ALMOST ANYWHERE IN THE CWA...POTENTIALLY EVEN
WEST OF THE SPC DAY 2 SLIGHT RISK AREA. PLENTY OF UNCERTAINTY FOR
SURE.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 455 PM CDT MON JUL 8 2013
MAIN FORECAST CONCERNS
WILL BE CHANCES FOR THUNDERSTORMS TUESDAY NIGHT AND WEDNESDAY NIGHT
AND AGAIN SATURDAY NIGHT THROUGH MONDAY AND TEMPERATURES.
MODELS ARE FAIRLY SIMILAR IN BUILDING AN UPPER LEVEL RIDGE ACROSS
THE AREA DURING THE PERIOD...BUT THE DETAILS OF THE TIMING MAINLY
WEAK UPPER LEVEL WAVES THROUGH THE AREA ARE SOMEWHAT DIFFERENT
BETWEEN THE MODELS. THIS BRINGS SOME UNCERTAINTY IN WHEN THERE WILL
BE SOME CHANCES FOR THUNDERSTORMS.
A SURFACE COLD FRONT WILL MOVE TO THE SOUTH ACROSS THE SOUTHERN PART
OF THE FORECAST AREA DURING THE EVENING. AN UPPER LEVEL WAVE WILL
ALSO BE MOVING THROUGH THE AREA. EXPECT SOME THUNDERSTORMS ALONG
THAT BOUNDARY DURING THE EVENING...BUT OVERNIGHT THEY SHOULD MOVE
OUT OF THE AREA. MUCAPE IS THE HIGHEST DURING THE EARLY EVENING
HOURS AND DIMINISHES SOME LATER IN THE EVENING...BUT STILL REMAINS
AROUND 2500 J/KG. EXPECT THAT THERE COULD BE SOME SEVERE WEATHER
DURING THE EVENING.
A COOL SURFACE HIGH PRESSURE SYSTEM SETTLES INTO THE AREA ON
WEDNESDAY. HIGH TEMPERATURES WILL BE AROUND 10 DEGREES COOLER THAN
ON TUESDAY. WEDNESDAY SHOULD REMAIN DRY...BUT AN UPPER LEVEL WAVE
MOVES ACROSS THE RIDGE AND THERE COULD BE SOME ISOLATED SHOWERS AND
THUNDERSTORMS THAT MOVE OFF THE HIGH PLAINS DURING THE NIGHT TIME
HOURS.
THE SURFACE HIGH MOVES OFF TO THE EAST ON THURSDAY AND THE SURFACE
PRESSURE GRADIENT TIGHTENS. WINDS AT 850MB ARE ONLY 20 TO 25 KTS SO
EXPECT SOME BREEZY CONDITIONS. WITH WINDS FROM THE SOUTH THE
TEMPERATURES WILL WARM UP.
THE UPPER LEVEL RIDGE CONTINUES TO BUILD ACROSS THE AREA FOR THE
PERIOD THURSDAY THROUGH SATURDAY. EXPECT TEMPERATURES TO WARM A
LITTLE EACH DAY THROUGH THE PERIOD.
THE UPPER LEVEL RIDGE REMAINS IN PLACE FOR SATURDAY NIGHT THROUGH
MONDAY...BUT IT IS MORE OF AN UPPER LEVEL HIGH PRESSURE SYSTEM
ACROSS THE AREA. IT IS FAIRLY BROAD AND THERE ARE A FEW UPPER LEVEL
WAVES THAT MOVE THROUGH THE AREA. SIMILAR TO THE PAST WEEK OR SO
EACH OF THESE UPPER LEVEL WAVES HAS A CHANCE FOR SOME THUNDERSTORMS.
DO NOT EXPECT THAT IT WILL BE WIDESPREAD OR THAT EVERYONE WILL HAVE
SOME PRECIPITATION. THE TIMING AND THE LOCATION OF ANY PRECIPITATION
IS IN QUESTION. WITH A FEW MORE CLOUDS AND THE CHANCE FOR SOME
PRECIPITATION THE TEMPERATURES WILL BE A LITTLE COOLER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1255 AM CDT TUE JUL 9 2013
REST OF TNGT: VFR -RA/THUNDER LIKELY THRU 07Z THEN EXPECT DRY WX
THEREAFTER. WINDS WILL BE VARIABLE AROUND PCPN. LLWS. MAYBE A
TOUCH OF MVFR FOG NEAR DAYBREAK?
TUE: VFR WITH SW WINDS 10 KTS OR LESS. WINDS MAY BECOME LGT AND
VARIABLE 17-21Z. THEN COOL FRONT WILL SHIFT WINDS TO NW. THERE
COULD BE SOME ISOLATED TSTM ACTIVITY NEARBY AFTER 21Z.
TUE THRU 06Z: VFR. NW WINDS AROUND 10 KTS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...HEAT ADVISORY FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR
NEZ085>087.
KS...HEAT ADVISORY FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR
KSZ005>007-017>019.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...PFANNKUCH
LONG TERM...JCB
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
154 PM EDT TUE JUL 9 2013
.SYNOPSIS...
UNSETTLED WEATHER WILL CONTINUE INTO THURSDAY, AS A SERIES OF
DISTURBANCES COMBINE WITH A WARM MOIST AIRMASS OVER OUR AREA TO
PRODUCE OCCASIONAL SHOWERS AND THUNDERSTORMS. DRIER AND COOLER AIR
WILL FINALLY ARRIVE ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
10 AM UPDATE...
GRIDS IN GOOD SHAPE. SMALL ADJUSTMENTS MADE TO THE POPS BUT IN
GENERAL IT LOOKED GOOD. SCATTERED SHOWER MOVING INTO STEUBEN NOW
WILL INCREASE IN COVERAGE AND TSTORMS WILL JOIN THEM. SEVERE
POTENTIAL MARGINAL BUT SOME SHOWERS AND TSTORMS WILL HAVE HEAVY
RAIN. STORM MOTION ONLY SLIGHTLY BETTER THAN YESTERDAY AT 10 TO 15
MPH. TEMPS ADJUSTED UP IN THE SE WHERE SOME SUNSHINE HAS PUSHED
TEMPS INTO THE U70S ALREADY.
UPDATED AT 630 AM. JUST A FEW MINOR TWEAKS TO THE FORECAST TO
ACCOUNT FOR THE LATEST TRENDS. HAVE ADDED PATCHY FOG TO SOUTHERN
NY AND NORTHERN PA THROUGH 13Z. ALSO RADAR IS DETECTING A FEW
SPRINKLES OR LIGHT SHOWERS OVER NORTHERN STEUBEN COUNTY. THESE
SHOWERS ARE DIMINISHING AS THEY MOVE EAST AND ARE NOT EXPECTED TO
REACH AS FAR EAST AS EVEN ELMIRA OR SYRACUSE THROUGH 9 AM.
PREVIOUS DISCUSSION IS BELOW.
LATEST WATER VAPOR LOOP SHOWS A BAND OF MOISTURE PROGRESSING
EASTWARD ACROSS NY AND PA THIS MORNING WITH A SMALL AREA OF DRYING
JUST TO THE WEST... THEN ANOTHER WAVE OF MOISTURE MOVING EAST
ACROSS THE WESTERN GREAT LAKES. EXPECT EACH OF THESE FEATURES TO
AFFECT OUR AREA THROUGH LATE THIS AFTERNOON. CLOUDS AND SCATTERED
LIGHT SHOWERS WILL OVERSPREAD THE AREA THIS MORNING... THEN EXPECT
SOME CLEARING BY AFTERNOON FOLLOWED BY A ROUND OF SCATTERED
THUNDERSTORMS INTO THIS EVENING. MODELS ALL INDICATE MODEST
SYNOPTIC SCALE FORCING FOR ASCENT MOVING ACROSS THE AREA THIS
AFTERNOON IN THE FORM OF A SFC-700 MB TROUGH AND WEAK WAA. THIS
SHOULD RESULT IN A SLIGHTLY GREATER COVERAGE OF STORMS THIS
AFTERNOON WITH POPS INCREASING TO AROUND 50 PCT.
LATEST RAP FORECAST SOUNDINGS INDICATE MLCAPE VALUES INCREASING TO
BETWEEN 800 AND 1000 J/KG BY LATE THIS AFTERNOON. WIND PROFILES
APPEAR TO BE RATHER LIGHT WTIH ONLY 10 TO 20 KTS OF WIND EXTENDING
UP THROUGH 500 MB. MODEST FORCING AND INSTABILITY ALONG WITH WEAK
WIND SHEAR SHOULD RESULT IN MOSTLY PULSE TYPE STORMS THIS
AFTERNOON WITH NOTHING MORE THAN AN ISOLATED... MARGINAL SEVERE
THREAT. ANY STORM COULD ALSO CONTAIN HEAVY DOWMPOURS ONCE AGAIN AS
PWAT VALUES APPROACH 2.00 INCHES... ALTHOUGH THE SHEAR DOES NOT
APPEAR TO BE STRONG ENOUGH TO SUPPORT ORGANIZED LONG-LASTING
STORMS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
SHOWERS AND THUNDERSTORMS WILL DECREASE IN COVERAGE THIS EVENING
WITH LOSS OF HEATING AND PASSAGE OF THE TROUGH TO THE EAST OF THE
AREA. ANOTHER ROUND OF SHOWERS AND STORMS APPEARS LIKELY ON
WEDNESDAY AS A COLD FRONT APPROACHES FROM THE WEST ALONG WITH MID-
LEVEL HEIGHT FALLS OF 30 TO 50 M ASSOCIATED WITH AN UPPER TROUGH
MOVING EAST ACROSS SOUTHERN CANADA. EXPECT MLCAPE VALUES TO ONCE
AGAIN REACH NEAR 1000 J/KG ACROSS THE AREA WEDNESDAY AFTERNOON...
AND THIS WILL BE ACCOMPANIED BY DEEP LAYER SHEAR INCREASING TO 20
TO 30 KTS WITH THE APPROACH OF THE UPPER LEVEL TROUGH. THIS
SCENARIO WOULD LEAD TO A GREATER CHANCE OF SEVERE WEATHER
WEDNESDAY AFTERNOON WITH SOME LINEAR ORGANIZATION OF THE
CONVECTION ALONG A PRE-FRONTAL TROUGH POSSIBLY RESULTING IN
STRONG DAMAING WINDS. BASED ON THESE FACTORS THE SPC DAY 2
CONVECTIVE OUTLOOK INDICATES A SLIGHT RISK OF SEVERE STORMS
WEDNESDAY AFTERNOON EXTENDING FROM THE OHIO VALLEY ACROSS NY AND
PA.
MODEL CONSENSUS INDICATES THAT THE COLD FRONT WILL BE MOVING EAST
OF OUR AREA ON THURSDAY WITH THE BEST CHC OF SHOWERS AND STORMS
THURSDAY AFTERNOON EXTENDING FROM EASTERN NY INTO NEW ENGLAND.
STILL A CHC OF SHOWERS AND STORMS WILL EXIST IN OUR AREA
ESPECIALLY EAST OF I-81. SLIGHTLY COOLER AND DRYER AIR WILL FOLLOW
BEHIND THIS FRONT THURSDAY NIGHT INTO FRIDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
MIDWEST RDGG TRIES TO BUILD IN DURING THE LONG TERM BUT BOTH THE
GFS AND EURO SHOW PERSISTENT UPR TROFINESS...PRIMARILY OVER THE
ERN ZONES...THRU THE PD. THIS MAY RESULT IN A SCENARIO WHERE THE
FCST AREA EAST OF THE I81 CORRIDOR IS SUSCEPTIPLE TO AFTN CONV
UNDER THE COOL POOL. NORMALLY WLD BE WARY OF BEING SO SPECIFIC IN
THE XNTDD BUT BOTH THE MODELS SHOWING THE UPR LOW IN THE SAME PSN
LEADS TO A HIGHER CONFIDENCE FCST. THE GFS EVENTUALLY FORMS A CLSD
LOW THAT DRFTS SE INTO THE MID ATLANTIC WHILE THE EURO BRIEFLY
FORMS AN UPR LOW BUT REALLY JUST BACKS THE WRN ATLANTIC RDG INTO
THE AREA PUSHING THE CSTLYMOISTURE CONVEYOR WWRD. EFFECT ON THE
SENSIBLE WX IS THE SAME EITHER WAY. A SLOW INCRS IN AFTN TEMPS
ALONG WITH AN INCRSD CHANCE OF MAINLY AFTN SHWRS AND TRWS THRU THE
END OF THE XTNDD PD.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
ONCE AGAIN WE SEE SCT CONV DVLPMT THIS AFTN AS AN UPR WV INTERACTS
WITH DAYTIME HTG. BEST CHANCE OF DVLPMT WILL BE ALONG THE SRN TIER
INTO NEPA WHERE BETTER HTG HAS TRIGGERED THE CONV TEMPS. HAVE
INCLUDED A TEMPO GROUP FOR TRWS ACROSS THE CNTRL AND SRN TAFS
SITES. ACTIVITY SHD DIE AGAIN THIS EVENING AS WE LOSE HTG. FOG
DVLPMT SEEMS LIKELY ONCE AGAIN TNGT WITH CROSSOVER TEMPS IN THE
MID AND UPR 60S AND WET GND IN SOME AREAS WITH THE SHWRS. XPCT
LIFR AT ELM DEEP IN THE VLY...MVFR MOST OTER PLACES WITH BRIEF IFR
PSBL. MIXING/CLRG BACK TO VFR AFT SUNRISE WED.
.OUTLOOK...
THU...PRIMARILY VFR BUT WITH RESTRICTIONS IN SCT SHWRS AND TRWS.
IFR WITH OVRNGT VLY FOG PSBL.
FRI/SAT/SUN...VFR WITH BRIEF IFR IN VLY FOG.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MSE/TAC
NEAR TERM...MSE/TAC
SHORT TERM...MSE
LONG TERM...DGM
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1031 AM EDT TUE JUL 9 2013
.SYNOPSIS...
UNSETTLED WEATHER WILL CONTINUE INTO THURSDAY, AS A SERIES OF
DISTURBANCES COMBINE WITH A WARM MOIST AIRMASS OVER OUR AREA TO
PRODUCE OCCASIONAL SHOWERS AND THUNDERSTORMS. DRIER AND COOLER AIR
WILL FINALLY ARRIVE ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
10 AM UPDATE...
GRIDS IN GOOD SHAPE. SMALL ADJUSTMENTS MADE TO THE POPS BUT IN
GENERAL IT LOOKED GOOD. SCATTERED SHOWER MOVING INTO STEUBEN NOW
WILL INCREASE IN COVERAGE AND TSTORMS WILL JOIN THEM. SEVERE
POTENTIAL MARGINAL BUT SOME SHOWERS AND TSTORMS WILL HAVE HEAVY
RAIN. STORM MOTION ONLY SLIGHTLY BETTER THAN YESTERDAY AT 10 TO 15
MPH. TEMPS ADJUSTED UP IN THE SE WHERE SOME SUNSHINE HAS PUSHED
TEMPS INTO THE U70S ALREADY.
UPDATED AT 630 AM. JUST A FEW MINOR TWEAKS TO THE FORECAST TO
ACCOUNT FOR THE LATEST TRENDS. HAVE ADDED PATCHY FOG TO SOUTHERN
NY AND NORTHERN PA THROUGH 13Z. ALSO RADAR IS DETECTING A FEW
SPRINKLES OR LIGHT SHOWERS OVER NORTHERN STEUBEN COUNTY. THESE
SHOWERS ARE DIMINISHING AS THEY MOVE EAST AND ARE NOT EXPECTED TO
REACH AS FAR EAST AS EVEN ELMIRA OR SYRACUSE THROUGH 9 AM.
PREVIOUS DISCUSSION IS BELOW.
LATEST WATER VAPOR LOOP SHOWS A BAND OF MOISTURE PROGRESSING
EASTWARD ACROSS NY AND PA THIS MORNING WITH A SMALL AREA OF DRYING
JUST TO THE WEST... THEN ANOTHER WAVE OF MOISTURE MOVING EAST
ACROSS THE WESTERN GREAT LAKES. EXPECT EACH OF THESE FEATURES TO
AFFECT OUR AREA THROUGH LATE THIS AFTERNOON. CLOUDS AND SCATTERED
LIGHT SHOWERS WILL OVERSPREAD THE AREA THIS MORNING... THEN EXPECT
SOME CLEARING BY AFTERNOON FOLLOWED BY A ROUND OF SCATTERED
THUNDERSTORMS INTO THIS EVENING. MODELS ALL INDICATE MODEST
SYNOPTIC SCALE FORCING FOR ASCENT MOVING ACROSS THE AREA THIS
AFTERNOON IN THE FORM OF A SFC-700 MB TROUGH AND WEAK WAA. THIS
SHOULD RESULT IN A SLIGHTLY GREATER COVERAGE OF STORMS THIS
AFTERNOON WITH POPS INCREASING TO AROUND 50 PCT.
LATEST RAP FORECAST SOUNDINGS INDICATE MLCAPE VALUES INCREASING TO
BETWEEN 800 AND 1000 J/KG BY LATE THIS AFTERNOON. WIND PROFILES
APPEAR TO BE RATHER LIGHT WTIH ONLY 10 TO 20 KTS OF WIND EXTENDING
UP THROUGH 500 MB. MODEST FORCING AND INSTABILITY ALONG WITH WEAK
WIND SHEAR SHOULD RESULT IN MOSTLY PULSE TYPE STORMS THIS
AFTERNOON WITH NOTHING MORE THAN AN ISOLATED... MARGINAL SEVERE
THREAT. ANY STORM COULD ALSO CONTAIN HEAVY DOWMPOURS ONCE AGAIN AS
PWAT VALUES APPROACH 2.00 INCHES... ALTHOUGH THE SHEAR DOES NOT
APPEAR TO BE STRONG ENOUGH TO SUPPORT ORGANIZED LONG-LASTING
STORMS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
SHOWERS AND THUNDERSTORMS WILL DECREASE IN COVERAGE THIS EVENING
WITH LOSS OF HEATING AND PASSAGE OF THE TROUGH TO THE EAST OF THE
AREA. ANOTHER ROUND OF SHOWERS AND STORMS APPEARS LIKELY ON
WEDNESDAY AS A COLD FRONT APPROACHES FROM THE WEST ALONG WITH MID-
LEVEL HEIGHT FALLS OF 30 TO 50 M ASSOCIATED WITH AN UPPER TROUGH
MOVING EAST ACROSS SOUTHERN CANADA. EXPECT MLCAPE VALUES TO ONCE
AGAIN REACH NEAR 1000 J/KG ACROSS THE AREA WEDNESDAY AFTERNOON...
AND THIS WILL BE ACCOMPANIED BY DEEP LAYER SHEAR INCREASING TO 20
TO 30 KTS WITH THE APPROACH OF THE UPPER LEVEL TROUGH. THIS
SCENARIO WOULD LEAD TO A GREATER CHANCE OF SEVERE WEATHER
WEDNESDAY AFTERNOON WITH SOME LINEAR ORGANIZATION OF THE
CONVECTION ALONG A PRE-FRONTAL TROUGH POSSIBLY RESULTING IN
STRONG DAMAING WINDS. BASED ON THESE FACTORS THE SPC DAY 2
CONVECTIVE OUTLOOK INDICATES A SLIGHT RISK OF SEVERE STORMS
WEDNESDAY AFTERNOON EXTENDING FROM THE OHIO VALLEY ACROSS NY AND
PA.
MODEL CONSENSUS INDICATES THAT THE COLD FRONT WILL BE MOVING EAST
OF OUR AREA ON THURSDAY WITH THE BEST CHC OF SHOWERS AND STORMS
THURSDAY AFTERNOON EXTENDING FROM EASTERN NY INTO NEW ENGLAND.
STILL A CHC OF SHOWERS AND STORMS WILL EXIST IN OUR AREA
ESPECIALLY EAST OF I-81. SLIGHTLY COOLER AND DRYER AIR WILL FOLLOW
BEHIND THIS FRONT THURSDAY NIGHT INTO FRIDAY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
330 AM UPDATE...NO MAJOR CHANGES TO THE PREVIOUS FORECAST. STILL
LOOKING LIKE WE MAY SEE AT LEAST A FEW DAYS OF DRY WEATHER
STARTING FRIDAY...ESPECIALLY BASED ON THE NEW 0Z EURO. I DID
MAINTAIN OUR GOING FORECAST OF SLIGHT TO LOW CHANCE (20 TO 30%)
POPS THIS WEEKEND WITH THE GFS HINTING AT A DISTURBANCE ALOFT IN
THE NORTHEAST DURING THIS TIME. THIS ALSO MATCHES UP WITH POP
GUIDANCE FROM WPC. WITH THAT SAID BASED ON THE EURO AND SURFACE
HIGH PRESSURE BUILDING IN...THE REALITY MAY BE A DRY WEEKEND. THE
PREVIOUS AFD IS BELOW...
STAGNANT PTRN CONTS TO MAKE FOR A TRICKY XTNDD PD. LATEST
OPERATIONAL GFS RUN TRENDS TWRDS LAST NGT/S EURO WITH THU/S BRIEF
RDGG GIVING WAY TO YET ANOTHER RETROGRADING OFF SHORE TROF.
MASSIVE BERMUDA HI CONTS TO BLOCK THE EWRD PROGRESS OF NRN STREAM
WV/S KEEPING THE NORTH BOUND TROPICAL FLOW IN PLACE ALONG THE CST
NEAR TO OUR FCST AREA. FOR NOW...IT LOOKS LIKE THE MAJORITY OF THE
MOISTURE ASSOCIATED WITH CHANTAL WELL EAST OF THE AREA...BUT WITH
THE UNCERTAINTY...THIS DEEP MOISTURE WILL NEED TO BE MONITORED.
DAILY SENSIBLE WX WILL SHOW SOME IMPRMNT ALTHOUGH THE ERN AND SRN
AREA WILL CONT TO BE NEAR THE EDGE OF THE DEEP MOISTURE AND MORE
AT RISK OF TRWS...ESP LATE IN THE PD. GNRLY FLWD HPC GUID BUT
NUDGED THE DATA TWRD THE MEX AND NEARER TO THE SURROUNDING OFFICES.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
12Z UPDATE...
IFR RESTRICTIONS LIKELY TO CONTINUE IN DENSE FOG AT KBGM AND KELM
THROUGH ABOUT 13Z BEFORE IMPROVEMENT TO VFR. ELSEWHERE MAINLY VFR
TODAY OVERALL. SCT SHOWERS WITH SOME THUNDER POSSIBLE ESPECIALLY
BETWEEN 18Z AND 0Z. SOME BRIEF MVFR OR IFR RESTRICTIONS DUE TO
HEAVY RAIN (VSBY) POSSIBLE. AT THIS POINT TOO UNCERTAIN TO INCLUDE
IN THE TAFS BUT AS WE GET CLOSER...SOME SHORT TERM TEMPOS MAY BE NEEDED.
.OUTLOOK...
WED THRU THU...PRIMARILY VFR BUT WITH RESTRICTIONS IN SCT
SHWRS AND TRWS. IFR WITH OVRNGT VLY FOG PSBL.
FRI/SAT...VFR WITH BRIEF IFR IN VLY FOG.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MSE/TAC
NEAR TERM...MSE/TAC
SHORT TERM...MSE
LONG TERM...DGM/HEDEN
AVIATION...HEDEN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
817 AM EDT TUE JUL 9 2013
.SYNOPSIS...
UNSETTLED WEATHER WILL CONTINUE INTO THURSDAY, AS A SERIES OF
DISTURBANCES COMBINE WITH A WARM MOIST AIRMASS OVER OUR AREA TO
PRODUCE OCCASIONAL SHOWERS AND THUNDERSTORMS. DRIER AND COOLER AIR
WILL FINALLY ARRIVE ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED AT 630 AM. JUST A FEW MINOR TWEAKS TO THE FORECAST TO
ACCOUNT FOR THE LATEST TRENDS. HAVE ADDED PATCHY FOG TO SOUTHERN
NY AND NORTHERN PA THROUGH 13Z. ALSO RADAR IS DETECTING A FEW
SPRINKLES OR LIGHT SHOWERS OVER NORTHERN STEUBEN COUNTY. THESE
SHOWERS ARE DIMINISHING AS THEY MOVE EAST AND ARE NOT EXPECTED TO
REACH AS FAR EAST AS EVEN ELMIRA OR SYRACUSE THROUGH 9 AM.
PREVIOUS DISCUSSION IS BELOW.
LATEST WATER VAPOR LOOP SHOWS A BAND OF MOISTURE PROGRESSING
EASTWARD ACROSS NY AND PA THIS MORNING WITH A SMALL AREA OF DRYING
JUST TO THE WEST... THEN ANOTHER WAVE OF MOISTURE MOVING EAST
ACROSS THE WESTERN GREAT LAKES. EXPECT EACH OF THESE FEATURES TO
AFFECT OUR AREA THROUGH LATE THIS AFTERNOON. CLOUDS AND SCATTERED
LIGHT SHOWERS WILL OVERSPREAD THE AREA THIS MORNING... THEN EXPECT
SOME CLEARING BY AFTERNOON FOLLOWED BY A ROUND OF SCATTERED
THUNDERSTORMS INTO THIS EVENING. MODELS ALL INDICATE MODEST
SYNOPTIC SCALE FORCING FOR ASCENT MOVING ACROSS THE AREA THIS
AFTERNOON IN THE FORM OF A SFC-700 MB TROUGH AND WEAK WAA. THIS
SHOULD RESULT IN A SLIGHTLY GREATER COVERAGE OF STORMS THIS
AFTERNOON WITH POPS INCREASING TO AROUND 50 PCT.
LATEST RAP FORECAST SOUNDINGS INDICATE MLCAPE VALUES INCREASING TO
BETWEEN 800 AND 1000 J/KG BY LATE THIS AFTERNOON. WIND PROFILES
APPEAR TO BE RATHER LIGHT WTIH ONLY 10 TO 20 KTS OF WIND EXTENDING
UP THROUGH 500 MB. MODEST FORCING AND INSTABILITY ALONG WITH WEAK
WIND SHEAR SHOULD RESULT IN MOSTLY PULSE TYPE STORMS THIS
AFTERNOON WITH NOTHING MORE THAN AN ISOLATED... MARGINAL SEVERE
THREAT. ANY STORM COULD ALSO CONTAIN HEAVY DOWMPOURS ONCE AGAIN AS
PWAT VALUES APPROACH 2.00 INCHES... ALTHOUGH THE SHEAR DOES NOT
APPEAR TO BE STRONG ENOUGH TO SUPPORT ORGANIZED LONG-LASTING
STORMS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
SHOWERS AND THUNDERSTORMS WILL DECREASE IN COVERAGE THIS EVENING
WITH LOSS OF HEATING AND PASSAGE OF THE TROUGH TO THE EAST OF THE
AREA. ANOTHER ROUND OF SHOWERS AND STORMS APPEARS LIKELY ON
WEDNESDAY AS A COLD FRONT APPROACHES FROM THE WEST ALONG WITH MID-
LEVEL HEIGHT FALLS OF 30 TO 50 M ASSOCIATED WITH AN UPPER TROUGH
MOVING EAST ACROSS SOUTHERN CANADA. EXPECT MLCAPE VALUES TO ONCE
AGAIN REACH NEAR 1000 J/KG ACROSS THE AREA WEDNESDAY AFTERNOON...
AND THIS WILL BE ACCOMPANIED BY DEEP LAYER SHEAR INCREASING TO 20
TO 30 KTS WITH THE APPROACH OF THE UPPER LEVEL TROUGH. THIS
SCENARIO WOULD LEAD TO A GREATER CHANCE OF SEVERE WEATHER
WEDNESDAY AFTERNOON WITH SOME LINEAR ORGANIZATION OF THE
CONVECTION ALONG A PRE-FRONTAL TROUGH POSSIBLY RESULTING IN
STRONG DAMAING WINDS. BASED ON THESE FACTORS THE SPC DAY 2
CONVECTIVE OUTLOOK INDICATES A SLIGHT RISK OF SEVERE STORMS
WEDNESDAY AFTERNOON EXTENDING FROM THE OHIO VALLEY ACROSS NY AND
PA.
MODEL CONSENSUS INDICATES THAT THE COLD FRONT WILL BE MOVING EAST
OF OUR AREA ON THURSDAY WITH THE BEST CHC OF SHOWERS AND STORMS
THURSDAY AFTERNOON EXTENDING FROM EASTERN NY INTO NEW ENGLAND.
STILL A CHC OF SHOWERS AND STORMS WILL EXIST IN OUR AREA
ESPECIALLY EAST OF I-81. SLIGHTLY COOLER AND DRYER AIR WILL FOLLOW
BEHIND THIS FRONT THURSDAY NIGHT INTO FRIDAY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
330 AM UPDATE...NO MAJOR CHANGES TO THE PREVIOUS FORECAST. STILL
LOOKING LIKE WE MAY SEE AT LEAST A FEW DAYS OF DRY WEATHER
STARTING FRIDAY...ESPECIALLY BASED ON THE NEW 0Z EURO. I DID
MAINTAIN OUR GOING FORECAST OF SLIGHT TO LOW CHANCE (20 TO 30%)
POPS THIS WEEKEND WITH THE GFS HINTING AT A DISTURBANCE ALOFT IN
THE NORTHEAST DURING THIS TIME. THIS ALSO MATCHES UP WITH POP
GUIDANCE FROM WPC. WITH THAT SAID BASED ON THE EURO AND SURFACE
HIGH PRESSURE BUILDING IN...THE REALITY MAY BE A DRY WEEKEND. THE
PREVIOUS AFD IS BELOW...
STAGNANT PTRN CONTS TO MAKE FOR A TRICKY XTNDD PD. LATEST
OPERATIONAL GFS RUN TRENDS TWRDS LAST NGT/S EURO WITH THU/S BRIEF
RDGG GIVING WAY TO YET ANOTHER RETROGRADING OFF SHORE TROF.
MASSIVE BERMUDA HI CONTS TO BLOCK THE EWRD PROGRESS OF NRN STREAM
WV/S KEEPING THE NORTH BOUND TROPICAL FLOW IN PLACE ALONG THE CST
NEAR TO OUR FCST AREA. FOR NOW...IT LOOKS LIKE THE MAJORITY OF THE
MOISTURE ASSOCIATED WITH CHANTAL WELL EAST OF THE AREA...BUT WITH
THE UNCERTAINTY...THIS DEEP MOISTURE WILL NEED TO BE MONITORED.
DAILY SENSIBLE WX WILL SHOW SOME IMPRMNT ALTHOUGH THE ERN AND SRN
AREA WILL CONT TO BE NEAR THE EDGE OF THE DEEP MOISTURE AND MORE
AT RISK OF TRWS...ESP LATE IN THE PD. GNRLY FLWD HPC GUID BUT
NUDGED THE DATA TWRD THE MEX AND NEARER TO THE SURROUNDING OFFICES.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
12Z UPDATE...
IFR RESTRICTIONS LIKELY TO CONTINUE IN DENSE FOG AT KBGM AND KELM
THROUGH ABOUT 13Z BEFORE IMPROVEMENT TO VFR. ELSEWHERE MAINLY VFR
TODAY OVERALL. SCT SHOWERS WITH SOME THUNDER POSSIBLE ESPECIALLY
BETWEEN 18Z AND 0Z. SOME BRIEF MVFR OR IFR RESTRICTIONS DUE TO
HEAVY RAIN (VSBY) POSSIBLE. AT THIS POINT TOO UNCERTAIN TO INCLUDE
IN THE TAFS BUT AS WE GET CLOSER...SOME SHORT TERM TEMPOS MAY BE NEEDED.
.OUTLOOK...
WED THRU THU...PRIMARILY VFR BUT WITH RESTRICTIONS IN SCT
SHWRS AND TRWS. IFR WITH OVRNGT VLY FOG PSBL.
FRI/SAT...VFR WITH BRIEF IFR IN VLY FOG.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MSE/TAC
NEAR TERM...MSE
SHORT TERM...MSE
LONG TERM...DGM/HEDEN
AVIATION...HEDEN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
701 AM EDT TUE JUL 9 2013
.SYNOPSIS...
UNSETTLED WEATHER WILL CONTINUE INTO THURSDAY AS A SERIES OF
DISTURBANCES COMBINE WITH A WARM MOIST AIRMASS OVER OUR AREA TO
PRODUCE OCCASIONAL SHOWERS AND THUNDERSTORMS. DRYER AIR WILL
FINALLY ARRIVE ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED AT 630 AM. JUST A FEW MINOR TWEAKS TO THE FORECAST TO
ACCOUNT FOR THE LATEST TRENDS. HAVE ADDED PATCHY FOG TO SOUTHERN
NY AND NORTHERN PA THROUGH 13Z. ALSO RADAR IS DETECTING A FEW
SPRINKLES OR LIGHT SHOWERS OVER NORTHERN STEUBEN COUNTY. THESE
SHOWERS ARE DIMINISHING AS THEY MOVE EAST AND ARE NOT EXPECTED TO
REACH AS FAR EAST AS EVEN ELMIRA OR SYRACUSE THROUGH 9 AM.
PREVIOUS DISCUSSION IS BELOW.
LATEST WATER VAPOR LOOP SHOWS A BAND OF MOISTURE PROGRESSING
EASTWARD ACROSS NY AND PA THIS MORNING WITH A SMALL AREA OF DRYING
JUST TO THE WEST... THEN ANOTHER WAVE OF MOISTURE MOVING EAST
ACROSS THE WESTERN GREAT LAKES. EXPECT EACH OF THESE FEATURES TO
AFFECT OUR AREA THROUGH LATE THIS AFTERNOON. CLOUDS AND SCATTERED
LIGHT SHOWERS WILL OVERSPREAD THE AREA THIS MORNING... THEN EXPECT
SOME CLEARING BY AFTERNOON FOLLOWED BY A ROUND OF SCATTERED
THUNDERSTORMS INTO THIS EVENING. MODELS ALL INDICATE MODEST
SYNOPTIC SCALE FORCING FOR ASCENT MOVING ACROSS THE AREA THIS
AFTERNOON IN THE FORM OF A SFC-700 MB TROUGH AND WEAK WAA. THIS
SHOULD RESULT IN A SLIGHTLY GREATER COVERAGE OF STORMS THIS
AFTERNOON WITH POPS INCREASING TO AROUND 50 PCT.
LATEST RAP FORECAST SOUNDINGS INDICATE MLCAPE VALUES INCREASING TO
BETWEEN 800 AND 1000 J/KG BY LATE THIS AFTERNOON. WIND PROFILES
APPEAR TO BE RATHER LIGHT WTIH ONLY 10 TO 20 KTS OF WIND EXTENDING
UP THROUGH 500 MB. MODEST FORCING AND INSTABILITY ALONG WITH WEAK
WIND SHEAR SHOULD RESULT IN MOSTLY PULSE TYPE STORMS THIS
AFTERNOON WITH NOTHING MORE THAN AN ISOLATED... MARGINAL SEVERE
THREAT. ANY STORM COULD ALSO CONTAIN HEAVY DOWMPOURS ONCE AGAIN AS
PWAT VALUES APPROACH 2.00 INCHES... ALTHOUGH THE SHEAR DOES NOT
APPEAR TO BE STRONG ENOUGH TO SUPPORT ORGANIZED LONG-LASTING
STORMS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
SHOWERS AND THUNDERSTORMS WILL DECREASE IN COVERAGE THIS EVENING
WITH LOSS OF HEATING AND PASSAGE OF THE TROUGH TO THE EAST OF THE
AREA. ANOTHER ROUND OF SHOWERS AND STORMS APPEARS LIKELY ON
WEDNESDAY AS A COLD FRONT APPROACHES FROM THE WEST ALONG WITH MID-
LEVEL HEIGHT FALLS OF 30 TO 50 M ASSOCIATED WITH AN UPPER TROUGH
MOVING EAST ACROSS SOUTHERN CANADA. EXPECT MLCAPE VALUES TO ONCE
AGAIN REACH NEAR 1000 J/KG ACROSS THE AREA WEDNESDAY AFTERNOON...
AND THIS WILL BE ACCOMPANIED BY DEEP LAYER SHEAR INCREASING TO 20
TO 30 KTS WITH THE APPROACH OF THE UPPER LEVEL TROUGH. THIS
SCENARIO WOULD LEAD TO A GREATER CHANCE OF SEVERE WEATHER
WEDNESDAY AFTERNOON WITH SOME LINEAR ORGANIZATION OF THE
CONVECTION ALONG A PRE-FRONTAL TROUGH POSSIBLY RESULTING IN
STRONG DAMAING WINDS. BASED ON THESE FACTORS THE SPC DAY 2
CONVECTIVE OUTLOOK INDICATES A SLIGHT RISK OF SEVERE STORMS
WEDNESDAY AFTERNOON EXTENDING FROM THE OHIO VALLEY ACROSS NY AND
PA.
MODEL CONSENSUS INDICATES THAT THE COLD FRONT WILL BE MOVING EAST
OF OUR AREA ON THURSDAY WITH THE BEST CHC OF SHOWERS AND STORMS
THURSDAY AFTERNOON EXTENDING FROM EASTERN NY INTO NEW ENGLAND.
STILL A CHC OF SHOWERS AND STORMS WILL EXIST IN OUR AREA
ESPECIALLY EAST OF I-81. SLIGHTLY COOLER AND DRYER AIR WILL FOLLOW
BEHIND THIS FRONT THURSDAY NIGHT INTO FRIDAY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
330 AM UPDATE...NO MAJOR CHANGES TO THE PREVIOUS FORECAST. STILL
LOOKING LIKE WE MAY SEE AT LEAST A FEW DAYS OF DRY WEATHER
STARTING FRIDAY...ESPECIALLY BASED ON THE NEW 0Z EURO. I DID
MAINTAIN OUR GOING FORECAST OF SLIGHT TO LOW CHANCE (20 TO 30%)
POPS THIS WEEKEND WITH THE GFS HINTING AT A DISTURBANCE ALOFT IN
THE NORTHEAST DURING THIS TIME. THIS ALSO MATCHES UP WITH POP
GUIDANCE FROM WPC. WITH THAT SAID BASED ON THE EURO AND SURFACE
HIGH PRESSURE BUILDING IN...THE REALITY MAY BE A DRY WEEKEND. THE
PREVIOUS AFD IS BELOW...
STAGNANT PTRN CONTS TO MAKE FOR A TRICKY XTNDD PD. LATEST
OPERATIONAL GFS RUN TRENDS TWRDS LAST NGT/S EURO WITH THU/S BRIEF
RDGG GIVING WAY TO YET ANOTHER RETROGRADING OFF SHORE TROF.
MASSIVE BERMUDA HI CONTS TO BLOCK THE EWRD PROGRESS OF NRN STREAM
WV/S KEEPING THE NORTH BOUND TROPICAL FLOW IN PLACE ALONG THE CST
NEAR TO OUR FCST AREA. FOR NOW...IT LOOKS LIKE THE MAJORITY OF THE
MOISTURE ASSOCIATED WITH CHANTAL WELL EAST OF THE AREA...BUT WITH
THE UNCERTAINTY...THIS DEEP MOISTURE WILL NEED TO BE MONITORED.
DAILY SENSIBLE WX WILL SHOW SOME IMPRMNT ALTHOUGH THE ERN AND SRN
AREA WILL CONT TO BE NEAR THE EDGE OF THE DEEP MOISTURE AND MORE
AT RISK OF TRWS...ESP LATE IN THE PD. GNRLY FLWD HPC GUID BUT
NUDGED THE DATA TWRD THE MEX AND NEARER TO THE SURROUNDING OFFICES.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
12Z UPDATE...
IFR RESTRICTIONS LIKELY TO CONTINUE IN DENSE FOG AT KBGM AND KELM
THROUGH ABOUT 13Z BEFORE IMPROVEMENT TO VFR. ELSEWHERE MAINLY VFR
TODAY OVERALL. SCT SHOWERS WITH SOME THUNDER POSSIBLE ESPECIALLY
BETWEEN 18Z AND 0Z. SOME BRIEF MVFR OR IFR RESTRICTIONS DUE TO
HEAVY RAIN (VSBY) POSSIBLE. AT THIS POINT TOO UNCERTAIN TO INCLUDE
IN THE TAFS BUT AS WE GET CLOSER...SOME SHORT TERM TEMPOS MAY BE NEEDED.
.OUTLOOK...
WED THRU THU...PRIMARILY VFR BUT WITH RESTRICTIONS IN SCT
SHWRS AND TRWS. IFR WITH OVRNGT VLY FOG PSBL.
FRI/SAT...VFR WITH BRIEF IFR IN VLY FOG.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MSE
NEAR TERM...MSE
SHORT TERM...MSE
LONG TERM...DGM/HEDEN
AVIATION...HEDEN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
633 AM EDT TUE JUL 9 2013
.SYNOPSIS...
UNSETTLED WEATHER WILL CONTINUE INTO THURSDAY AS A SERIES OF
DISTURBANCES COMBINE WITH A WARM MOIST AIRMASS OVER OUR AREA TO
PRODUCE OCCASIONAL SHOWERS AND THUNDERSTORMS. DRYER AIR WILL
FINALLY ARRIVE ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED AT 630 AM. JUST A FEW MINOR TWEAKS TO THE FORECAST TO
ACCOUNT FOR THE LATEST TRENDS. HAVE ADDED PATCHY FOG TO SOUTHERN
NY AND NORTHERN PA THROUGH 13Z. ALSO RADAR IS DETECTING A FEW
SPRINKLES OR LIGHT SHOWERS OVER NORTHERN STEUBEN COUNTY. THESE
SHOWERS ARE DIMINISHING AS THEY MOVE EAST AND ARE NOT EXPECTED TO
REACH AS FAR EAST AS EVEN ELMIRA OR SYRACUSE THROUGH 9 AM.
PREVIOUS DISCUSSION IS BELOW.
LATEST WATER VAPOR LOOP SHOWS A BAND OF MOISTURE PROGRESSING
EASTWARD ACROSS NY AND PA THIS MORNING WITH A SMALL AREA OF DRYING
JUST TO THE WEST... THEN ANOTHER WAVE OF MOISTURE MOVING EAST
ACROSS THE WESTERN GREAT LAKES. EXPECT EACH OF THESE FEATURES TO
AFFECT OUR AREA THROUGH LATE THIS AFTERNOON. CLOUDS AND SCATTERED
LIGHT SHOWERS WILL OVERSPREAD THE AREA THIS MORNING... THEN EXPECT
SOME CLEARING BY AFTERNOON FOLLOWED BY A ROUND OF SCATTERED
THUNDERSTORMS INTO THIS EVENING. MODELS ALL INDICATE MODEST
SYNOPTIC SCALE FORCING FOR ASCENT MOVING ACROSS THE AREA THIS
AFTERNOON IN THE FORM OF A SFC-700 MB TROUGH AND WEAK WAA. THIS
SHOULD RESULT IN A SLIGHTLY GREATER COVERAGE OF STORMS THIS
AFTERNOON WITH POPS INCREASING TO AROUND 50 PCT.
LATEST RAP FORECAST SOUNDINGS INDICATE MLCAPE VALUES INCREASING TO
BETWEEN 800 AND 1000 J/KG BY LATE THIS AFTERNOON. WIND PROFILES
APPEAR TO BE RATHER LIGHT WTIH ONLY 10 TO 20 KTS OF WIND EXTENDING
UP THROUGH 500 MB. MODEST FORCING AND INSTABILITY ALONG WITH WEAK
WIND SHEAR SHOULD RESULT IN MOSTLY PULSE TYPE STORMS THIS
AFTERNOON WITH NOTHING MORE THAN AN ISOLATED... MARGINAL SEVERE
THREAT. ANY STORM COULD ALSO CONTAIN HEAVY DOWMPOURS ONCE AGAIN AS
PWAT VALUES APPROACH 2.00 INCHES... ALTHOUGH THE SHEAR DOES NOT
APPEAR TO BE STRONG ENOUGH TO SUPPORT ORGANIZED LONG-LASTING
STORMS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
SHOWERS AND THUNDERSTORMS WILL DECREASE IN COVERAGE THIS EVENING
WITH LOSS OF HEATING AND PASSAGE OF THE TROUGH TO THE EAST OF THE
AREA. ANOTHER ROUND OF SHOWERS AND STORMS APPEARS LIKELY ON
WEDNESDAY AS A COLD FRONT APPROACHES FROM THE WEST ALONG WITH MID-
LEVEL HEIGHT FALLS OF 30 TO 50 M ASSOCIATED WITH AN UPPER TROUGH
MOVING EAST ACROSS SOUTHERN CANADA. EXPECT MLCAPE VALUES TO ONCE
AGAIN REACH NEAR 1000 J/KG ACROSS THE AREA WEDNESDAY AFTERNOON...
AND THIS WILL BE ACCOMPANIED BY DEEP LAYER SHEAR INCREASING TO 20
TO 30 KTS WITH THE APPROACH OF THE UPPER LEVEL TROUGH. THIS
SCENARIO WOULD LEAD TO A GREATER CHANCE OF SEVERE WEATHER
WEDNESDAY AFTERNOON WITH SOME LINEAR ORGANIZATION OF THE
CONVECTION ALONG A PRE-FRONTAL TROUGH POSSIBLY RESULTING IN
STRONG DAMAING WINDS. BASED ON THESE FACTORS THE SPC DAY 2
CONVECTIVE OUTLOOK INDICATES A SLIGHT RISK OF SEVERE STORMS
WEDNESDAY AFTERNOON EXTENDING FROM THE OHIO VALLEY ACROSS NY AND
PA.
MODEL CONSENSUS INDICATES THAT THE COLD FRONT WILL BE MOVING EAST
OF OUR AREA ON THURSDAY WITH THE BEST CHC OF SHOWERS AND STORMS
THURSDAY AFTERNOON EXTENDING FROM EASTERN NY INTO NEW ENGLAND.
STILL A CHC OF SHOWERS AND STORMS WILL EXIST IN OUR AREA
EXPECIALLY EAST OF I-81. SLIGHTLY COOLER AND DRYER AIR WILL FOLLOW
BEHIND THIS FRONT THURSDAY NIGHT INTO FRIDAY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
330 AM UPDATE...NO MAJOR CHANGES TO THE PREVIOUS FORECAST. STILL
LOOKING LIKE WE MAY SEE AT LEAST A FEW DAYS OF DRY WEATHER
STARTING FRIDAY...ESPECIALLY BASED ON THE NEW 0Z EURO. I DID
MAINTAIN OUR GOING FORECAST OF SLIGHT TO LOW CHANCE (20 TO 30%)
POPS THIS WEEKEND WITH THE GFS HINTING AT A DISTURBANCE ALOFT IN
THE NORTHEAST DURING THIS TIME. THIS ALSO MATCHES UP WITH POP
GUIDANCE FROM WPC. WITH THAT SAID BASED ON THE EURO AND SURFACE
HIGH PRESSURE BUILDING IN...THE REALITY MAY BE A DRY WEEKEND. THE
PREVIOUS AFD IS BELOW...
STAGNANT PTRN CONTS TO MAKE FOR A TRICKY XTNDD PD. LATEST
OPERATIONAL GFS RUN TRENDS TWRDS LAST NGT/S EURO WITH THU/S BRIEF
RDGG GIVING WAY TO YET ANOTHER RETROGRADING OFF SHORE TROF.
MASSIVE BERMUDA HI CONTS TO BLOCK THE EWRD PROGRESS OF NRN STREAM
WV/S KEEPING THE NORTH BOUND TROPICAL FLOW IN PLACE ALONG THE CST
NEAR TO OUR FCST AREA. FOR NOW...IT LOOKS LIKE THE MAJORITY OF THE
MOISTURE ASSOCIATED WITH CHANTAL WELL EAST OF THE AREA...BUT WITH
THE UNCERTAINTY...THIS DEEP MOISTURE WILL NEED TO BE MONITORED.
DAILY SENSIBLE WX WILL SHOW SOME IMPRMNT ALTHOUGH THE ERN AND SRN
AREA WILL CONT TO BE NEAR THE EDGE OF THE DEEP MOISTURE AND MORE
AT RISK OF TRWS...ESP LATE IN THE PD. GNRLY FLWD HPC GUID BUT
NUDGED THE DATA TWRD THE MEX AND NEARER TO THE SURROUNDING OFFICES.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
06Z UPDATE...
PERIODS OF FOG...PRODUCING IFR RESTRICTIONS ARE POSSIBLE THROUGH
DAYBREAK ESPECIALLY AT KELM/KITH/KBGM WITH THESE SITES SEEING THE
MOST RAIN MONDAY AFTERNOON. A COMPLICATING FACTOR WILL BE AN AREA
OF HIGH CLOUDS NOW OVER WESTERN NY THAT WILL SLIDE EAST DURING
THIS PERIOD. WITH IFR RESTRICTIONS ALREADY AT ALL THREE SITES
BEING TEMPERED BY THIS HIGH CLOUD THREAT...ELECTED TO MAINLY GO
WITH TEMPO GROUPS FOR IFR GIVEN THE HIGH VARIABILITY EXPECTED
THROUGHOUT THE NIGHT. KELM STANDS THE BEST CHANCE FOR GOING DOWN
AND STAYING DOWN. ELSEWHERE VFR IS EXPECTED.
ANY FOG SHOULD BURN OFF BETWEEN 12Z AND 13Z. AFTER THAT A
DISTURBANCE MOVING THROUGH LATER IN THE DAY WILL BRING SCT.
SHOWERS TO THE TERMINALS MAINLY DURING THE PEAK HEATING (18Z -
0Z). WHILE THUNDER IS POSSIBLE I DID NOT INCLUDE IN THE TAFS JUST
YET GIVEN THE EXPECTED SCT. COVERAGE.
.OUTLOOK...
WED THRU THU...PRIMARILY VFR BUT WITH RESTRICTIONS IN SCT
SHWRS AND TRWS. IFR WITH OVRNGT VLY FOG PSBL.
FRI/SAT...VFR WITH BRIEF IFR IN VLY FOG.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MSE
NEAR TERM...MSE
SHORT TERM...MSE
LONG TERM...DGM/HEDEN
AVIATION...HEDEN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
424 AM EDT TUE JUL 9 2013
.SYNOPSIS...
UNSETTLED WEATHER WILL CONTINUE INTO THURSDAY AS A SERIES OF
DISTURBANCES COMBINE WITH A WARM MOIST AIRMASS OVER OUR AREA TO
PRODUCE OCCASIONAL SHOWERS AND THUNDERSTORMS. DRYER AIR WILL
FINALLY ARRIVE ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST WATER VAPOR LOOP SHOWS A BAND OF MOISTURE PROGRESSING
EASTWARD ACROSS NY AND PA THIS MORNING WITH A SMALL AREA OF DRYING
JUST TO THE WEST... THEN ANOTHER WAVE OF MOISTURE MOVING EAST
ACROSS THE WESTERN GREAT LAKES. EXPECT EACH OF THESE FEATURES TO
AFFECT OUR AREA THROUGH LATE THIS AFTERNOON. CLOUDS AND SCATTERED
LIGHT SHOWERS WILL OVERSPREAD THE AREA THIS MORNING... THEN EXPECT
SOME CLEARING BY AFTERNOON FOLLOWED BY A ROUND OF SCATTERED
THUNDERSTORMS INTO THIS EVENING. MODELS ALL INDICATE MODEST
SYNOPTIC SCALE FORCING FOR ASCENT MOVING ACROSS THE AREA THIS
AFTERNOON IN THE FORM OF A SFC-700 MB TROUGH AND WEAK WAA. THIS
SHOULD RESULT IN A SLIGHTLY GREATER COVERAGE OF STORMS THIS
AFTERNOON WITH POPS INCREASING TO AROUND 50 PCT.
LATEST RAP FORECAST SOUNDINGS INDICATE MLCAPE VALUES INCREASING TO
BETWEEN 800 AND 1000 J/KG BY LATE THIS AFTERNOON. WIND PROFILES
APPEAR TO BE RATHER LIGHT WTIH ONLY 10 TO 20 KTS OF WIND EXTENDING
UP THROUGH 500 MB. MODEST FORCING AND INSTABILITY ALONG WITH WEAK
WIND SHEAR SHOULD RESULT IN MOSTLY PULSE TYPE STORMS THIS
AFTERNOON WITH NOTHING MORE THAN AN ISOLATED... MARGINAL SEVERE
THREAT. ANY STORM COULD ALSO CONTAIN HEAVY DOWMPOURS ONCE AGAIN AS
PWAT VALUES APPROACH 2.00 INCHES... ALTHOUGH THE SHEAR DOES NOT
APPEAR TO BE STRONG ENOUGH TO SUPPORT ORGANIZED LONG-LASTING
STORMS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
SHOWERS AND THUNDERSTORMS WILL DECREASE IN COVERAGE THIS EVENING
WITH LOSS OF HEATING AND PASSAGE OF THE TROUGH TO THE EAST OF THE
AREA. ANOTHER ROUND OF SHOWERS AND STORMS APPEARS LIKELY ON
WEDNESDAY AS A COLD FRONT APPROACHES FROM THE WEST ALONG WITH MID-
LEVEL HEIGHT FALLS OF 30 TO 50 M ASSOCIATED WITH AN UPPER TROUGH
MOVING EAST ACROSS SOUTHERN CANADA. EXPECT MLCAPE VALUES TO ONCE
AGAIN REACH NEAR 1000 J/KG ACROSS THE AREA WEDNESDAY AFTERNOON...
AND THIS WILL BE ACCOMPANIED BY DEEP LAYER SHEAR INCREASING TO 20
TO 30 KTS WITH THE APPROACH OF THE UPPER LEVEL TROUGH. THIS
SCENARIO WOULD LEAD TO A GREATER CHANCE OF SEVERE WEATHER
WEDNESDAY AFTERNOON WITH SOME LINEAR ORGANIZATION OF THE
CONVECTION ALONG A PRE-FRONTAL TROUGH POSSIBLY RESULTING IN
STRONG DAMAING WINDS. BASED ON THESE FACTORS THE SPC DAY 2
CONVECTIVE OUTLOOK INDICATES A SLIGHT RISK OF SEVERE STORMS
WEDNESDAY AFTERNOON EXTENDING FROM THE OHIO VALLEY ACROSS NY AND
PA.
MODEL CONSENSUS INDICATES THAT THE COLD FRONT WILL BE MOVING EAST
OF OUR AREA ON THURSDAY WITH THE BEST CHC OF SHOWERS AND STORMS
THURSDAY AFTERNOON EXTENDING FROM EASTERN NY INTO NEW ENGLAND.
STILL A CHC OF SHOWERS AND STORMS WILL EXIST IN OUR AREA
EXPECIALLY EAST OF I-81. SLIGHTLY COOLER AND DRYER AIR WILL FOLLOW
BEHIND THIS FRONT THURSDAY NIGHT INTO FRIDAY.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
330 AM UPDATE...NO MAJOR CHANGES TO THE PREVIOUS FORECAST. STILL
LOOKING LIKE WE MAY SEE AT LEAST A FEW DAYS OF DRY WEATHER
STARTING FRIDAY...ESPECIALLY BASED ON THE NEW 0Z EURO. I DID
MAINTAIN OUR GOING FORECAST OF SLIGHT TO LOW CHANCE (20 TO 30%)
POPS THIS WEEKEND WITH THE GFS HINTING AT A DISTURBANCE ALOFT IN
THE NORTHEAST DURING THIS TIME. THIS ALSO MATCHES UP WITH POP
GUIDANCE FROM WPC. WITH THAT SAID BASED ON THE EURO AND SURFACE
HIGH PRESSURE BUILDING IN...THE REALITY MAY BE A DRY WEEKEND. THE
PREVIOUS AFD IS BELOW...
STAGNANT PTRN CONTS TO MAKE FOR A TRICKY XTNDD PD. LATEST
OPERATIONAL GFS RUN TRENDS TWRDS LAST NGT/S EURO WITH THU/S BRIEF
RDGG GIVING WAY TO YET ANOTHER RETROGRADING OFF SHORE TROF.
MASSIVE BERMUDA HI CONTS TO BLOCK THE EWRD PROGRESS OF NRN STREAM
WV/S KEEPING THE NORTH BOUND TROPICAL FLOW IN PLACE ALONG THE CST
NEAR TO OUR FCST AREA. FOR NOW...IT LOOKS LIKE THE MAJORITY OF THE
MOISTURE ASSOCIATED WITH CHANTAL WELL EAST OF THE AREA...BUT WITH
THE UNCERTAINTY...THIS DEEP MOISTURE WILL NEED TO BE MONITORED.
DAILY SENSIBLE WX WILL SHOW SOME IMPRMNT ALTHOUGH THE ERN AND SRN
AREA WILL CONT TO BE NEAR THE EDGE OF THE DEEP MOISTURE AND MORE
AT RISK OF TRWS...ESP LATE IN THE PD. GNRLY FLWD HPC GUID BUT
NUDGED THE DATA TWRD THE MEX AND NEARER TO THE SURROUNDING OFFICES.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
06Z UPDATE...
PERIODS OF FOG...PRODUCING IFR RESTRICTIONS ARE POSSIBLE THROUGH
DAYBREAK ESPECIALLY AT KELM/KITH/KBGM WITH THESE SITES SEEING THE
MOST RAIN MONDAY AFTERNOON. A COMPLICATING FACTOR WILL BE AN AREA
OF HIGH CLOUDS NOW OVER WESTERN NY THAT WILL SLIDE EAST DURING
THIS PERIOD. WITH IFR RESTRICTIONS ALREADY AT ALL THREE SITES
BEING TEMPERED BY THIS HIGH CLOUD THREAT...ELECTED TO MAINLY GO
WITH TEMPO GROUPS FOR IFR GIVEN THE HIGH VARIABILITY EXPECTED
THROUGHOUT THE NIGHT. KELM STANDS THE BEST CHANCE FOR GOING DOWN
AND STAYING DOWN. ELSEWHERE VFR IS EXPECTED.
ANY FOG SHOULD BURN OFF BETWEEN 12Z AND 13Z. AFTER THAT A
DISTURBANCE MOVING THROUGH LATER IN THE DAY WILL BRING SCT.
SHOWERS TO THE TERMINALS MAINLY DURING THE PEAK HEATING (18Z -
0Z). WHILE THUNDER IS POSSIBLE I DID NOT INCLUDE IN THE TAFS JUST
YET GIVEN THE EXPECTED SCT. COVERAGE.
.OUTLOOK...
WED THRU THU...PRIMARILY VFR BUT WITH RESTRICTIONS IN SCT
SHWRS AND TRWS. IFR WITH OVRNGT VLY FOG PSBL.
FRI/SAT...VFR WITH BRIEF IFR IN VLY FOG.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MSE
NEAR TERM...MSE
SHORT TERM...MSE
LONG TERM...DGM/HEDEN
AVIATION...HEDEN
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1038 PM EDT WED JUL 10 2013
.SYNOPSIS...
BERMUDA HIGH PRESSURE WILL REMAIN OFFSHORE THROUGH THE WEEK. A COLD
FRONT WILL APPROACH FROM THE NORTHWEST LATE THURSDAY BEFORE STALLING
INLAND ACROSS THE CAROLINAS FRIDAY. REMNANTS OF TROPICAL STORM
CHANTAL MAY APPROACH THE SOUTHEAST COAST THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AS OF 1030 PM WEDNESDAY...BASED ON LATEST RADAR TRENDS...HAVE
REDUCED POPS TO 10 PERCENT INLAND AND 20 PERCENT ALONG THE COAST FOR
TONIGHT. RADAR IS DEPICTING A BIT OF A SWIRL IN ECHOES OFFSHORE.
THIS LOOKS TO BE A WEAK TROUGH OF LOW PRESSURE...PERHAPS WITH A
SMALL SCALE LOW PRESSURE CENTER EMBEDDED WITHIN IT. THIS FEATURE IS
PRODUCING A SLIGHT ENHANCEMENT IN ACTIVITY OFF THE COAST...SOME OF
WHICH MAY MOVE ONSHORE IN THE NEXT TWO TO THREE HOURS. RAINFALL
AMOUNTS ARE EXPECTED TO BE LIGHT. WE ARE SEEING SOME INCREASE IN
CLOUD COVER ACROSS THE AREA...MAINLY FROM UPSTREAM CONVECTIVE DEBRIS
SO PARTLY CLOUDY SHOULD COVER IT FOR THE NIGHT. MIN TEMPERATURES IN
THE LOW TO MID 70S AND LIGHT WINDS LOOK TO BE ON TAP FOR THE NIGHT.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...A FRONTAL BOUNDARY IS PUSHING INTO THE
CAROLINAS LATE THURSDAY AND WILL STALL OVER THE FORECAST AREA FOR
THE REMAINDER OF THE PERIOD. THE ISSUE IS THE PRECIPITABLE WATERS
WILL BE VERY HIGH JUST BELOW 2 STANDARD DEVIATION ABOVE NORMAL.
COVERAGE OF PRECIPITATION IS EXPECTED TO BE NUMEROUS SO WITH THE
ANTECEDENT CONDITIONS THIS COULD WILL LEAD TO POSSIBLE FLOODING
THREAT FOR THE AREA. THE BEST LIFT AND DEEPEST MOISTURE IS
EXPECTED ON FRIDAY AND THUS AM ANTICIPATING THAT A FLOOD WATCH
MAY HAVE TO BE ISSUED ON THURSDAY.
WITH DEEP MOISTURE...CLOUDS AND CONVECTION HIGHS WILL REACH THE
MID TO UPPER 80S ON THURSDAY AND THE MID 80S ON FRIDAY.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 3 PM WEDNESDAY...DEEP LAYER SHEAR AXIS WILL LIE ACROSS THE
CAROLINAS OVER THE WEEKEND. AT THE SURFACE THIS WILL BE THE REMNANTS
OF A DISSIPATING COLD FRONT. ALOFT THE FEATURE WILL BE FURTHER WEST
AND THE REMNANTS OF A WEAKENED UPPER TROUGH BETWEEN BUILDING RIDGES
OVER THE WEST ATLANTIC AND THE NATIONS MIDSECTION. THE RESULTING
DEEP ONSHORE FLOW SHOULD FOCUS PLENTY OF MOISTURE INTO COASTAL
ZONES. INLAND AREAS MAY SEE LESS WIDESPREAD RAINFALL CHANCES AND
AMOUNTS IN COMPARISON BUT THE PROXIMITY OF THE UPPER FORCING MAY
OFFSET THIS ENOUGH SUCH THAT THIS FAR OUT IN TIME INLAND POPS ONLY
SLIGHTLY LOWER THAN COASTAL POPS. TOUGH CALL ON SUNDAY AS MOST OF
THE AFOREMENTIONED FEATURES SEEM TO REALLY WASH OUT. THERE MAY BE
LITTLE LEFT FOR SUCH AN UNSETTLED DAY AS PREV THOUGHT UNLESS OUTFLOW
AND DIFFERENTIAL HEATING BOUNDARIES LINGER. FOR NOW WILL SHOW
ANOTHER FAIRLY UNSETTLED DAY AS THERE IS SIMILARLY LITTLE TO
SUPPRESS CONVECTION AND PLENTY OF MOISTURE WILL LINGER ESP IF
CHANTAL MOISTURE MAKES IT THIS FAR NORTH. THAT SUPPRESSION MAY TAKE
SHAPE ON MONDAY HOWEVER AS THE TWO UPPER RIDGES BOTH IMPINGE ON THE
AREA. ODD LOOKING UPPER LOW RETROGRADING SSW BETWEEN THEM THOUGH
EARLY NEXT WEEK. SOME GUIDANCE KEEPING THIS FEATURE FAR ENOUGH WEST
TO MINIMIZE ITS IMPACT LOCALLY WHEREAS OTHERS CLOSER TO THE COAST
AND SHOW IT LOOKING LIKE OUR NEXT RAIN MAKER.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 00Z...THE RADAR HAS BEEN QUIET WITH LITTLE CONVECTIVE ACTIVITY
TO SPEAK OF THIS AFTN/EVENING. THE LATEST HRRR RUNS DO NOT SHOW MUCH
IN THE WAY OF FURTHER DEVELOPMENT TONIGHT...SO DO NOT ANTICIPATE ANY
AVIATION IMPACTS. VFR SHOULD PREVAIL OVERNIGHT...ALTHOUGH LIGHT
FOG/STRATUS CANNOT BE RULED OUT DUE TO THE LACK OF CONVECTIVE DEBRIS
CLOUDS OVER THE AREA. HAVE INCLUDED TEMPO MVFR CIGS ALONG THE COAST
BETWEEN 09-12Z...WHILE THE INLAND TERMS COULD SEE SOME LIGHT FOG
AND/OR SCT CLOUDS BELOW 1KFT BEFORE DAYBREAK. PCPN CHANCES INCREASE
ON THURSDAY AS A COLD FRONT AND DEEPENING UPPER TROUGH APPROACH FROM
OUR WEST. SHOWERS/T-STORMS AHEAD OF THE FRONT SHOULD REACH KFLO/KLBT
IN THE EARLY AFTN. SOME CONVECTION IS ALSO POSSIBLE BY LATE MORNING
AT THE COASTAL SITES ALONG THE SEA BREEZE. STRONGER STORMS WILL BE
CAPABLE OF PRODUCING LOCALIZED GUSTY WINDS AND BRIEF PERIODS OF
IFR/MVFR. S/SW WINDS DURING THE DAY WILL BE IN THE 8-12 KT RANGE.
EXTENDED OUTLOOK...SHOWERS/T-STORMS LIKELY ON FRIDAY WITH MVFR AND
LOCALIZED PERIODS OF IFR. ELEVATED PCPN CHANCES CONTINUE THROUGH THE
WEEKEND...WITH SCT STORMS POSSIBLE ON MONDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 PM WEDNESDAY...EXPECT SOUTH TO SOUTHWEST WINDS OF 10-15
KNOTS TONIGHT WITH SEAS AROUND 3 FT. WEAK TROUGH OFFSHORE COULD
TEMPORARILY TAKE WINDS EAST OF SOUTH FOR THE NEXT TWO TO THREE HOURS
BUT A RETURN TO MORE S TO SW FLOW IS EXPECTED AFTER THAT. ISOLATED
TO SCATTERED SHOWERS AND POSSIBLY THUNDERSTORMS...ARE EXPECTED AS
WELL.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...SOUTH TO SOUTHWEST FLOW IS EXPECTED OVER
THE WATERS THIS PERIOD AND A SLIGHT INCREASE IN WINDS AS THE GRADIENT
TIGHTENS WITH A FRONT APPROACHING THE WATERS LATE THURSDAY INTO
FRIDAY. SEAS WILL SLOWLY BUILD WITH SMALL CRAFT CONDITIONS POSSIBLE
FOR A FEW HOURS FRIDAY NIGHT. THESE 6 FOOT SEAS WILL BE MAINLY AT
20 MILES OFF THE COAST NORTH OF LITTLE RIVER INLET. AS THE FRONT
STALLS EXPECT THE SEAS TO RELAX TO 3 TO 4 FEET.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 300 AM WEDNESDAY...STILL MUCH UNCERTAINTY IN THE EXTENDED DUE
TO POSSIBLE TS CHANTAL...BUT ATTM EXPECT ONLY MINIMAL IMPACTS FROM
THE SYSTEM. WEAK TS CHANTAL MAY APPROACH THE SE COAST DURING THE
WKND...BUT THIS IS ONLY IF SHE CAN HOLD TOGETHER OVER THE BAHAMA
ISLANDS...AND MOVE INTO THE WEAKNESS SW OF THE ATLANTIC RIDGE. WHILE
MUCH OF THE GUIDANCE KEEPS CHANTAL WEAK AND SW OF THE LOCAL
AREA...SOME LOW-AMPLITUDE SE SWELL WITH A 10 SEC PERIOD MAY COMBINE
WITH E/SE WINDS INCREASING TO AROUND 15 KTS TO BUILD WAVE HEIGHTS
SAT AND SUN. EXPECT SEAS ATTM TO BE PRIMARILY 2-4 FT...BUT SOME 5
FTERS WILL BE POSSIBLE...ESPECIALLY ACROSS THE SOUTHERN WATERS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...31
SHORT TERM...DRH
LONG TERM...MBB
AVIATION...BJR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
737 PM EDT WED JUL 10 2013
.SYNOPSIS...
BERMUDA HIGH PRESSURE WILL REMAIN OFFSHORE THROUGH THE WEEK. A COLD
FRONT WILL APPROACH FROM THE NORTHWEST LATE THURSDAY BEFORE STALLING
INLAND ACROSS THE CAROLINAS FRIDAY. REMNANTS OF TROPICAL STORM
CHANTAL MAY APPROACH THE SOUTHEAST COAST THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AS OF 730 PM WEDNESDAY...BASED ON LATEST RADAR TRENDS...HAVE LOWERED
POPS FOR THE EVENING TO THE SLIGHT CHANCE TO CHANCE CATEGORY AND
REDUCED CLOUD COVER AS WELL. STILL SOME POTENTIAL FOR SOME INCREASE
IN CLOUDS FROM UPSTREAM CONVECTIVE DEBRIS LATER TONIGHT. FOR NOW
MIN TEMPERATURES IN THE LOW TO MID 70S AND LIGHT S TO SW WINDS LOOK
TO BE ON TRACK.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...A FRONTAL BOUNDARY IS PUSHING INTO THE
CAROLINAS LATE THURSDAY AND WILL STALL OVER THE FORECAST AREA FOR
THE REMAINDER OF THE PERIOD. THE ISSUE IS THE PRECIPITABLE WATERS
WILL BE VERY HIGH JUST BELOW 2 STANDARD DEVIATION ABOVE NORMAL.
COVERAGE OF PRECIPITATION IS EXPECTED TO BE NUMEROUS SO WITH THE
ANTECEDENT CONDITIONS THIS COULD WILL LEAD TO POSSIBLE FLOODING
THREAT FOR THE AREA. THE BEST LIFT AND DEEPEST MOISTURE IS
EXPECTED ON FRIDAY AND THUS AM ANTICIPATING THAT A FLOOD WATCH
MAY HAVE TO BE ISSUED ON THURSDAY.
WITH DEEP MOISTURE...CLOUDS AND CONVECTION HIGHS WILL REACH THE
MID TO UPPER 80S ON THURSDAY AND THE MID 80S ON FRIDAY.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 3 PM WEDNESDAY...DEEP LAYER SHEAR AXIS WILL LIE ACROSS THE
CAROLINAS OVER THE WEEKEND. AT THE SURFACE THIS WILL BE THE REMNANTS
OF A DISSIPATING COLD FRONT. ALOFT THE FEATURE WILL BE FURTHER WEST
AND THE REMNANTS OF A WEAKENED UPPER TROUGH BETWEEN BUILDING RIDGES
OVER THE WEST ATLANTIC AND THE NATIONS MIDSECTION. THE RESULTING
DEEP ONSHORE FLOW SHOULD FOCUS PLENTY OF MOISTURE INTO COASTAL
ZONES. INLAND AREAS MAY SEE LESS WIDESPREAD RAINFALL CHANCES AND
AMOUNTS IN COMPARISON BUT THE PROXIMITY OF THE UPPER FORCING MAY
OFFSET THIS ENOUGH SUCH THAT THIS FAR OUT IN TIME INLAND POPS ONLY
SLIGHTLY LOWER THAN COASTAL POPS. TOUGH CALL ON SUNDAY AS MOST OF
THE AFOREMENTIONED FEATURES SEEM TO REALLY WASH OUT. THERE MAY BE
LITTLE LEFT FOR SUCH AN UNSETTLED DAY AS PREV THOUGHT UNLESS OUTFLOW
AND DIFFERENTIAL HEATING BOUNDARIES LINGER. FOR NOW WILL SHOW
ANOTHER FAIRLY UNSETTLED DAY AS THERE IS SIMILARLY LITTLE TO
SUPPRESS CONVECTION AND PLENTY OF MOISTURE WILL LINGER ESP IF
CHANTAL MOISTURE MAKES IT THIS FAR NORTH. THAT SUPPRESSION MAY TAKE
SHAPE ON MONDAY HOWEVER AS THE TWO UPPER RIDGES BOTH IMPINGE ON THE
AREA. ODD LOOKING UPPER LOW RETROGRADING SSW BETWEEN THEM THOUGH
EARLY NEXT WEEK. SOME GUIDANCE KEEPING THIS FEATURE FAR ENOUGH WEST
TO MINIMIZE ITS IMPACT LOCALLY WHEREAS OTHERS CLOSER TO THE COAST
AND SHOW IT LOOKING LIKE OUR NEXT RAIN MAKER.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 00Z...THE RADAR HAS BEEN QUIET WITH LITTLE CONVECTIVE ACTIVITY
TO SPEAK OF THIS AFTN/EVENING. THE LATEST HRRR RUNS DO NOT SHOW MUCH
IN THE WAY OF FURTHER DEVELOPMENT TONIGHT...SO DO NOT ANTICIPATE ANY
AVIATION IMPACTS. VFR SHOULD PREVAIL OVERNIGHT...ALTHOUGH LIGHT
FOG/STRATUS CANNOT BE RULED OUT DUE TO THE LACK OF CONVECTIVE DEBRIS
CLOUDS OVER THE AREA. HAVE INCLUDED TEMPO MVFR CIGS ALONG THE COAST
BETWEEN 09-12Z...WHILE THE INLAND TERMS COULD SEE SOME LIGHT FOG
AND/OR SCT CLOUDS BELOW 1KFT BEFORE DAYBREAK. PCPN CHANCES INCREASE
ON THURSDAY AS A COLD FRONT AND DEEPENING UPPER TROUGH APPROACH FROM
OUR WEST. SHOWERS/T-STORMS AHEAD OF THE FRONT SHOULD REACH KFLO/KLBT
IN THE EARLY AFTN. SOME CONVECTION IS ALSO POSSIBLE BY LATE MORNING
AT THE COASTAL SITES ALONG THE SEA BREEZE. STRONGER STORMS WILL BE
CAPABLE OF PRODUCING LOCALIZED GUSTY WINDS AND BRIEF PERIODS OF
IFR/MVFR. S/SW WINDS DURING THE DAY WILL BE IN THE 8-12 KT RANGE.
EXTENDED OUTLOOK...SHOWERS/T-STORMS LIKELY ON FRIDAY WITH MVFR AND
LOCALIZED PERIODS OF IFR. ELEVATED PCPN CHANCES CONTINUE THROUGH THE
WEEKEND...WITH SCT STORMS POSSIBLE ON MONDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 730 PM WEDNESDAY...EXPECT SOUTH TO SOUTHWEST WINDS OF 10-15
KNOTS TONIGHT WITH SEAS AROUND 3 FT. COULD BE ISOLATED SHOWERS OR
STORMS TONIGHT AS WELL...ESPECIALLY IF A LAND BREEZE SETS UP AFTER
MIDNIGHT.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...SOUTH TO SOUTHWEST FLOW IS EXPECTED OVER
THE WATERS THIS PERIOD AND A SLIGHT INCREASE IN WINDS AS THE GRADIENT
TIGHTENS WITH A FRONT APPROACHING THE WATERS LATE THURSDAY INTO
FRIDAY. SEAS WILL SLOWLY BUILD WITH SMALL CRAFT CONDITIONS POSSIBLE
FOR A FEW HOURS FRIDAY NIGHT. THESE 6 FOOT SEAS WILL BE MAINLY AT
20 MILES OFF THE COAST NORTH OF LITTLE RIVER INLET. AS THE FRONT
STALLS EXPECT THE SEAS TO RELAX TO 3 TO 4 FEET.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 300 AM WEDNESDAY...STILL MUCH UNCERTAINTY IN THE EXTENDED DUE
TO POSSIBLE TS CHANTAL...BUT ATTM EXPECT ONLY MINIMAL IMPACTS FROM
THE SYSTEM. WEAK TS CHANTAL MAY APPROACH THE SE COAST DURING THE
WKND...BUT THIS IS ONLY IF SHE CAN HOLD TOGETHER OVER THE BAHAMA
ISLANDS...AND MOVE INTO THE WEAKNESS SW OF THE ATLANTIC RIDGE. WHILE
MUCH OF THE GUIDANCE KEEPS CHANTAL WEAK AND SW OF THE LOCAL
AREA...SOME LOW-AMPLITUDE SE SWELL WITH A 10 SEC PERIOD MAY COMBINE
WITH E/SE WINDS INCREASING TO AROUND 15 KTS TO BUILD WAVE HEIGHTS
SAT AND SUN. EXPECT SEAS ATTM TO BE PRIMARILY 2-4 FT...BUT SOME 5
FTERS WILL BE POSSIBLE...ESPECIALLY ACROSS THE SOUTHERN WATERS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...31
SHORT TERM...DRH
LONG TERM...MBB
AVIATION...BJR
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
708 PM EDT WED JUL 10 2013
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO REMAIN OFF THE SOUTHEAST COAST
BRINGING HUMID SOUTH SOUTHWESTERLY WINDS. A COOL FRONT WILL SAG
INTO THE AREA AND STALL FOR LATE THURSDAY THROUGH THE WEEKEND.
HIGH PRESSURE WILL BUILD BACK IN FOR EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AS OF 655 PM WEDNESDAY...MOST OF THE CONVECTION IS REMAINING JUST
WEST AND NORTH OF OUR CWA THIS EVENING...WITH ONLY A FEW SPOTTY
SHOWERS/TSTMS OVER OUR FAR WESTERN COUNTIES. THE LATEST 4 KM HRR-R
AND RAP MODELS HAVE A GOOD FEEL FOR THE PLACEMENT OF THE
PRECIPITATION AND KEEP MINIMAL ACTIVITY OVER OUR CWA THROUGH
MIDNIGHT. WILL CONTINUE LOW CHANCES WEST OF HIGHWAY 17 THROUGH
MIDNIGHT. A NUMBER OF THE SHORT-RANGE AND HIGH-RES
MODELS...PARTICULARLY THE EMC WRF...INDICATE SOME LIGHT
PRECIPITATION WILL AFFECT THE COASTAL SECTIONS TOWARD MORNING AND
HAVE A SLIGHT CHC POP ALONG MOST OF THE ENTIRE COASTLINE ABOUT
MIDNIGHT. ANOTHER WARM AND MUGGY NIGHT WITH OVERNIGHT MINIMUM
TEMPERATURES WILL RANGE FROM ABOUT 71 IN KENANSVILLE TO 78 IN
MANTEO.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
AS OF 330 PM WED...UPPER LEVEL TROUGH WITH ITS ASSOCIATED COLD
FRONT WILL BE MOVING SOUTHEAST FROM THE GREAT LAKES/OHIO VALLEY
AND WILL BE INTERACTING WITH BOTH THE RIDGE ALOFT AND HIGH
PRESSURE OVER THE WESTERN ATLANTIC. AS THE TROUGH MOVES INTO OUR
AREA...VORT ENERGY WILL ACCOMPANY IT AND WILL HELP TRIGGER
ISOLATED/SCATTERED SHOWERS/TSTORMS. WITH AN INCREASE OF MOIST SW
FLOW (PWATS BTW 2.0-2.1")...THIS WILL RESULT IN PERIODS OF HVY
RAIN...AND COULD EASILY SEE HALF A INCH TO 1 INCH OF RAIN FOR
TOMORROW. ALSO...MAY CAUSE SOME MINOR FLOODING IN LOW LYING AREAS
WITH THE HVY RAINFALL. MAX TEMPERATURE ARE EXPECTED TO RANGE
MID/UPPER 80S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
AS OF 300 PM WEDNESDAY...MODELS IN GOOD AGREEMENT WITH UPR TROF
AND ASSOC CDFNT AFFECTING THE AREA DURG THE 1ST PART OF THE LONG
TERM THU NIGHT THROUGH FRI NIGHT. SHT WAVE ENERGY WILL AFFECT AREA
AND AMS MSTR WILL BE VERY HIGH WITH PWAT VALUES UP TO 2.5 INCHES.
THE FRONT WILL PROVIDE THE FOCUS FOR WIDESPREAD CONVECTION DURG
THIS TIME FRAME WITH HVY RAFL AND MINOR FLOODING PSBL. WILL LIKELY
SEE 1 TO 2 INCH RAINFALL AMTS WITH LOCALLY HIGHER VALUES.
BOTH GFS AND ECMWF INDICATE THE NRN END OF UPR TROF WILL BECOME
CUT-OFF AND THEN RETROGRADE SOUTHWEST JUST W OF THE AREA. HARD TO
SAY HOW MUCH MOISTURE FROM THE REMNANTS OF CHANTAL WILL AFFECT THE
AREA OVER THE WEEKEND INTO EARLY NEXT WEEK. FOR NOW HAVE SCT POPS IN
FOR THE WEEKEND INTO EARLY NEXT WEEK WITH THE UPR LOW/TROF AND SFC
FRONT LINGERING AND DSIPTG ACROSS THE AREA. MORE OF A DIURNAL
CONVECTION PATN WITH SCT CONVECTION MAINLY INLAND DURG THE DAY
STARTING TUE AND CONTG THROUGH MID WEEK.
BELOW NORMAL DAYTIME TEMPS EXPECTED SPLY THROUGH THE WEEKEND WITH
THE FRONT ACROSS THE AREA AND PLENTY OF CLOUD COVER. HIGH TEMPS
EXPECTED IN THE LOW TO MID 80S WITH LOWS NEAR 70 INLAND TO THE MID
70S COAST THROUGH MON...THEN HIGH PRES BUILDS IN WITH TEMPS GRDLY
CLIMBING TO NEAR 90 INLAND TO THE LWR AND MID 80S COAST...AND
LOWS LWR TO MID 70S.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
SHORT TERM /TONIGHT AND THURSDAY/...
AS OF 7 PM WED...MOSTLY VFR CONDITIONS THROUGH THE LATE NIGHT HOURS
WITH A LIGHT S/SW FLOW LESS AS VERY ISOLATED EVENING CONVECTION
DISSIPATES. THINK THERE COULD BE A SHORT PERIOD OF LOWER CEILINGS
TOWARD MORNING...ESPECIALLY AT KEWN AND KOAJ GIVEN THE CHANCE OF
SOME LIGHT PRECIPITATION SNEAKING IN OFF THE WATER AND PERHAPS
REACHING THOSE SITES. ON THURSDAY...SCATTERED CONVECTION WITH
LOWER CIGS/VSBYS WILL DEVELOP AS A COLD FRONT APPROACHES FROM THE
NORTHWEST. COVERAGE WILL BECOME MOST NUMEROUS IN THE AFTERNOON
ALONG THE COASTAL PLAIN AFFECTING TERMINALS PGV AND ISO.
CONVECTION NOT FORECAST TO REACH SEVERE LIMITS BUT SURFACE WIND
GUSTS WITH ANY STORM COULD APPROACH 35-40 KNOTS IN THE AFTERNOON.
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 300 PM WEDNESDAY...EXTENDED PERIOD OF SUB-VFR LIKELY THU
NIGHT THROUGH FRIDAY NIGHT WITH WDSPRD SHOWER/TSTMS WITH UPPER
TROF AND COLD FRONT ACRS THE AREA. SCT CONVECTION EXPECTED OVER
THE WEEKEND INTO EARLY NEXT WEEK WITH IFR STRATUS AND FOG PSBL
DURG THE LATE NIGHT/EARLY MORNING HOURS.
&&
.MARINE...
SHORT TERM /TONIGHT THROUGH THURSDAY/...
AS OF 705 PM WEDNESDAY...S/SW WINDS ARE A BIT GUSTY OVER THE
SOUNDS AND NORTHERN WATERS WITH 23 KNOTS OVER THE PAMLICO SOUND
AND AS HIGH AS 27 KNOTS AT OREGON INLET. WILL HAVE FORECAST WINDS
IN THE 15 TO 20 KNOT RANGE AND WILL MONITOR AND MAY NEED A ADJUST
THE SCA TIMES IF THESE TRENDS CONTINUE. SEAS REMAIN IN THE 2 TO 4
FOOT RANGE. UPPER LEVEL TROUGH WILL BE DIGGING DOWN FROM THE
GREAT LAKES/OHIO VALLEY AND WILL BE INTERACTING WITH BOTH THE
RIDGE ALOFT AND HIGH PRESSURE OVER THE WESTERN ATLANTIC ON
THURSDAY. THIS WILL CAUSE THE WINDS TO FREQUENTLY GUST TO 25 KTS
WITH SEAS BUILDING TO 5-6 FT ALONG THE SOUTHERN/CENTRAL WATERS.
LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 300 PM WEDNESDAY...SCA CONDS CONT THU NIGHT FOR ALL OF THE
COASTAL WATERS INCLUDING PAMLICO SOUND WITH STG SW WINDS NEAR 20 KT
AND SEAS UP TO 6 FT SPLY ACRS THE OUTER PORTIONS OF THE COASTAL
WATERS. EXPECT FREQUENT GUSTS TO 25 KT IN PAMLICO SOUND THROUGH THU
NIGHT. NO CHANGES TO THE SCA HEADLINES. SCA CONDS CONT FOR SEAS
ACRS THE CNTRL AND SRN COASTAL WATERS THROUGH FRI MORN THEN SEAS
FALL BELOW 6 FT WITH A LESSENING PRES GRAD. APPEARS THE REMNANTS
OF CHANTAL WILL RMN WELL TO THE SOUTH AND HAVE MINIMAL IMPACT ON
THE AREA...BUT SHOULD CONT TO BE MONITORED. WINDS WILL BE SW-S 10-15
KT OVER THE WEEKEND AND SEAS GENERALLY 2-4 FT. S-SE WINDS 10-15 KT
EXPECTED ON MON WITH SEAS CONTG IN THE 2-4 FT RANGE.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM NOON THURSDAY TO 5 AM EDT FRIDAY FOR
AMZ135-150.
SMALL CRAFT ADVISORY FROM NOON THURSDAY TO NOON EDT FRIDAY FOR
AMZ152-154.
SMALL CRAFT ADVISORY FROM 8 PM THURSDAY TO NOON EDT FRIDAY FOR
AMZ156-158.
&&
$$
SYNOPSIS...BM
NEAR TERM...CTC
SHORT TERM...BM
LONG TERM...JAC
AVIATION...JAC/CTC/HSA
MARINE...JAC/CTC/BM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
257 PM EDT TUE JUL 9 2013
.SYNOPSIS...
A WEAK UPPER LEVEL LOW PRESSURE TROUGH WILL HOLD OVER THE EASTERN
U.S. THROUGH WEDNESDAY. A STRONGER UPPER LEVEL TROUGH AND ASSOCIATED
SURFACE COLD FRONT WILL APPROACH THE AREA FROM THE NORTHEAST LATE
WEDNESDAY... AND SWING THROUGH THE REGION THURSDAY THROUGH FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 PM TUESDAY...
THROUGH TONIGHT: WATER VAPOR IMAGERY SHOWS A SUBTLE VORTICITY MAX
DROPPING SOUTHEAST THROUGH CENTRAL... AND THIS FEATURE COMBINED WITH
DAYTIME HEATING/DESTABILIZATION (MLCAPE OF 2000-2500 J/KG) AND
ABUNDANT MOISTURE (PW VALUE HAVING REBOUNDED THIS AFTERNOON TO
1-8-2.0 IN.) HAVE LED TO SCATTERED STORMS... MORE NUMEROUS IN THE
SOUTHEAST CWA AS DEPICTED WELL BY EARLIER FORECASTS AND RECENT HRRR
MODEL RUNS. DEEP LAYER BULK SHEAR IS QUITE WEAK THOUGH WITH MARGINAL
D-CAPE... SO ANY PARTICULARLY STRONG STORMS SHOULD REMAIN
ISOLATED... BUT MIXED-PHASE CAPE AROUND 700 J/KG AND INCREASING
MOISTURE IN THE -10C TO -30C LAYER ACCORDING TO RAP FORECAST
SOUNDINGS SUGGESTS A THREAT OF SMALL HAIL WITH ANY STRONG CELL...
AND CERTAINLY LOCALLY HEAVY DOWNPOURS REMAIN A CONCERN GIVEN THE
SLOW MOVEMENT AND INCREASING PW. LOSS OF HEATING AS WELL AS THE
PASSAGE OF THE WEAK WAVE EAST OF THE AREA SHOULD BRING A GRADUAL
DISSIPATION OF CONVECTION BY CLOSE TO MIDNIGHT. FOLLOWING
PERSISTENCE WITH NO SIGNIFICANT CHANGE IN AIR MASS... REDEVELOPMENT
OF STRATUS IS ANTICIPATED ACROSS THE AREA LATE TONIGHT... WITH A
LINGERING THREAT OF ISOLATED SHALLOW SHOWERS MAINLY IN THE SOUTH AND
EAST WHERE ABUNDANT LOW LEVEL MOISTURE PERSISTS. LOWS CLOSE TO LAST
NIGHT... 70-74. -GIH
&&
.SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/...
AS OF 240 PM TUESDAY...
FOR WEDNESDAY/WEDNESDAY NIGHT: LOOKS LIKE MORE OF THE SAME... WITH A
CONTINUED HUMID AIR MASS AND MOIST COLUMN FEATURING PW VALUES OF
1.7-1.9 INCHES IN THE MORNING CLIMBING TO 1.9-2.1 INCHES IN THE
AFTERNOON... HIGHEST EAST. WEAK LEE SURFACE TROUGHING HOLDS IN PLACE
WITH A CONTINUATION OF LIGHT BREEZES FROM THE SW... WHILE IN THE MID
LEVELS... VERY WEAK FLOW FROM THE WNW NEAR THE ILL-DEFINED SHEAR
AXIS ALOFT WILL ALLOW FOR LITTLE TO NO DYNAMIC FORCING FOR ASCENT
THROUGH THE AFTERNOON... ALTHOUGH THIS FLOW DOES INCREASE SLIGHTLY
IN THE EVENING AND OVERNIGHT HOURS AS A STRONG WAVE DIGS INTO THE
MEAN TROUGH OVER THE GREAT LAKES. MLCAPE ONCE AGAIN SHOULD TOP OUT
AROUND 1500-2500 J/KG BUT WITH CONTINUED LOW DEEP-LAYER BULK SHEAR
OF JUST 10-15 KTS... SO EXPECT ANOTHER ROUND OF SCATTERED STORMS
WITH DESTABILIZATION... WITH HIGHEST POPS IN THE WRN CWA WHERE THE
SREF INDICATES THE BEST CHANCE OF MEASURABLE RAIN... BUT ANY STORMS
SHOULD HOLD BELOW SEVERE LIMITS. WILL RETAIN A MENTION OF ISOLATED
SHOWERS OVERNIGHT WITH THE IMPROVING FLOW ALOFT AND LINGERING LOW
LEVEL MOISTURE. HIGHS 86-90 AND LOWS AGAIN 70-74. -GIH
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 255 PM TUESDAY...
THE OVERALL PATTERN FOR THE LONG TERM WILL BE DOMINATED BY A
DEEPENING UPPER LEVEL TROUGH WITH ITS AXIS DIGGING TOWARDS THE EAST
COAST. AT THE SURFACE COASTAL NORTH CAROLINA WILL BE SANDWICHED
BETWEEN A STRENGTHENING SURFACE HIGH THAT WILL MOVE FROM THE GREAT
PLAINS TO THE GREAT LAKES AND THE SLOWLY RETREATING BERMUDA HIGH IN
THE SOUTHWESTERN ATLANTIC. IN BETWEEN A SURFACE LOW MOVING ACROSS
CENTRAL ONTARIO AND QUEBEC WILL SET UP A FRONTAL ZONE THAT WILL
EXTEND DOWN THE EASTERN SEABOARD...EVENTUALLY STALL OUT AND THEN
POTENTIALLY RETROGRADE NEAR THE END OF THE PERIOD. TOWARDS THE END
OF THE PERIOD THE X FACTOR WILL BE THE DEVELOPMENT AND TRACK OF
TROPICAL STORM CHANTAL.
THURSDAY AND FRIDAY: STARTING ON THURSDAY THE FRONTAL ZONE WILL BE
DRAPED ACROSS THE WESTERN PIEDMONT WHICH IS WHERE THE HIGHEST
PRECIPITATION CHANCES WILL BE. WITH PW VALUES IN EXCESS OF 2 INCHES.
CONVECTION FEATURING HEAVY RAIN IS PROBABLE WITH THE LEE TROUGH AND
DIFFERENTIAL HEATING BOUNDARIES THE MAIN FOCI FOR CONVECTION. WILL
KEEP HIGHEST POPS IN THE NW THURSDAY AFTERNOON BUT OVERSPREADING THE
ENTIRE CWA BY THURSDAY NIGHT. BY FRIDAY MORNING THE FOCUS FOR
CONVECTION WILL SHIFT FURTHER EAST AS THE SURFACE HIGH OVER THE
GREAT LAKES BUILDS INTO THE 1020S AND THE BERMUDA HIGH WEAKENS
SLIGHTLY. ONCE REACHING THE COASTAL PLAIN THE FRONT WILL SLOW AND
BECOME STAGNANT KEEPING THE BEST CHANCE FOR RAIN IN THE SOUTHEAST ON
FRIDAY WHERE PW VALUES WILL REMAIN ABOVE 2 INCHES. BACK TOWARDS THE
TRIANGLE PWS WILL DROP TO ABOUT 1.5 INCHES AND COVERAGE AND
INTENSITY OF PRECIPITATION SHOULD WANE. QPF WILL BE TRICKY ONCE
AGAIN AS CONVECTION WILL BE LOCALLY HEAVIER. FOR NOW WILL GO WITH
ABOUT AN INCH FOR THESE TWO DAYS COMBINED WITH SOME LOCALES
POTENTIALLY SEEING 2-3 INCHES IN HEAVIER AND TRAINING STORMS. STORM
TOTAL QPF SHOULD BE GREATER IN THE SOUTHEAST AND DECREASING BACK
TOWARDS THE TRIAD. MAX TEMPERATURES THESE TWO DAYS WILL BE IN THE
MID TO UPPER 80S WITH LOWS IN THE LOWER 70S AND POTENTIALLY SOME
UPPER 60S IN THE NORTHWEST ON FRIDAY NIGHT INTO SATURDAY MORNING AS
THE FRONT PUSHES EASTWARD. DEWPOINTS WILL BE DEPENDENT UPON LOCATION
WITH LOWER 70S COMMON AHEAD OF THE FRONT AND UPPER 60S BEHIND IT.
SATURDAY AND SUNDAY: THE HIGH TO THE NORTH WILL CONTINUE TO
STRENGTHEN KEEPING THE FRONTAL ZONE RESTRICTED TO THE COAST AS A CUT
OFF MESO LOW OFF OF THE NEW ENGLAND COAST WILL TAKE OVER FOR THE
PARENT LOW AND CONTINUE QUICKLY OFF TO THE NORTHEAST. THIS WILL
BEGIN TO WASH OUT THE FRONT A LITTLE. IN ADDITION THE HIGH WILL
BUILD DOWN FROM THE NORTH CAUSING THE FRONTAL ZONE TO TAKE A MORE
WEST TO EAST ORIENTATION. BEST CHANCES FOR PRECIP WILL BE IN THE
SOUTH AND EAST WITH DRIER CONDITIONS TO THE NW. ON SUNDAY WHATS LEFT
OF THE FRONT WILL START TO RETROGRADE BACK OVER THE CWA WITH NEW
MOISTURE TRANSPORT REINFORCEMENTS FROM TROPICAL STORM CHANTAL OR
WHATEVER THE REMNANTS MAY BE AT THAT TIME. PW VALUES WILL ONCE AGAIN
APPROACH 2 INCHES IN THE SOUTHERN HALF OF THE CWA. HIGHS ONCE AGAIN
IN THE MID TO UPPER 80S WITH LOWS UPPER 60S TO LOW 70S.
MONDAY AND TUESDAY: THIS PERIOD REMAINS LOW CONFIDENCE BECAUSE OF
THE UNCERTAINTY IN THE LOCATION AND STRENGTH OF CHANTAL AT THIS
TIME. THE BERMUDA HIGH WILL BEGIN TO MOVE BACK WESTWARD WHICH WILL
HELP TO FUNNEL MOISTURE IN FROM THE ATLANTIC. WILL KEEP CHANCE POPS
THROUGH THE PERIOD WITH HIGHEST CHANCES IN THE SOUTHEAST. TEMPS WILL
REMAIN MID TO UPPER 80S AND LOWS UPPER 60S TO LOW 70S.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 1245 PM TUESDAY...
MVFR CIGS WILL CONTINUE TO COME AND GO AT CENTRAL NC TAF SITES
THROUGH 20Z AS CLOUDS BASED AT 1-3 THOUSAND FT WILL VARY BETWEEN
SCATTERED AND BROKEN. EXPECT VFR CIGS AFTER 20Z. NUMEROUS SHOWERS
AND STORMS ARE EXPECTED BETWEEN 20Z AND 03Z WITH BEST COVERAGE NEAR
FAY/RWI... FEWER SHOWERS/STORMS AT RDU AND EVEN FEWER (SCATTERED AT
MOST) AT INT/GSO. IN/NEAR THESE STORMS... MVFR/IFR CIGS/VSBYS AND
BRIEF WIND GUSTS OVER 30 MPH ARE POSSIBLE. OTHERWISE... VFR
CONDITIONS AND LIGHT WINDS FROM THE SOUTH OR SW (UNDER 12 KTS) WILL
DOMINATE UNTIL AROUND 07Z... WHEN IFR STRATUS IS EXPECTED TO DEVELOP
ONCE AGAIN... AS HAS OCCURRED ON PREVIOUS MORNINGS. CIGS SHOULD LIFT
SLOWLY TO MVFR BY 16Z-18Z.
LOOKING BEYOND 18Z WEDNESDAY... CIGS ARE EXPECTED TO TREND TO VFR
18Z-20Z WEDNESDAY WITH SCATTERED STORMS DEVELOPING. IFR CONDITIONS
ARE LIKELY TO RETURN AFTER 07Z THURSDAY THROUGH MID MORNING...
LIFTING SLOWLY TO MVFR THEN VFR BY EARLY THURSDAY AFTERNOON.
OCCASIONALLY MVFR CONDITIONS ARE LIKELY WITH NUMEROUS SHOWERS AND
STORMS THURSDAY AFTERNOON THROUGH FRIDAY. MVFR CONDITIONS COULD
LINGER AT FAY THROUGH SUNDAY... BUT OTHERWISE VFR CONDITIONS ARE
EXPECTED TO DOMINATE FRIDAY NIGHT THROUGH SUNDAY... ALTHOUGH IFR
STRATUS IS AGAIN LIKELY 07Z-14Z SUNDAY MORNING. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...ELLIS
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
240 PM EDT TUE JUL 9 2013
.SYNOPSIS...
A WEAK UPPER LEVEL LOW PRESSURE TROUGH WILL HOLD OVER THE EASTERN
U.S. THROUGH WEDNESDAY. A STRONGER UPPER LEVEL TROUGH AND ASSOCIATED
SURFACE COLD FRONT WILL APPROACH THE AREA FROM THE NORTHEAST LATE
WEDNESDAY... AND SWING THROUGH THE REGION THURSDAY THROUGH FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 PM TUESDAY...
THROUGH TONIGHT: WATER VAPOR IMAGERY SHOWS A SUBTLE VORTICITY MAX
DROPPING SOUTHEAST THROUGH CENTRAL... AND THIS FEATURE COMBINED WITH
DAYTIME HEATING/DESTABILIZATION (MLCAPE OF 2000-2500 J/KG) AND
ABUNDANT MOISTURE (PW VALUE HAVING REBOUNDED THIS AFTERNOON TO
1-8-2.0 IN.) HAVE LED TO SCATTERED STORMS... MORE NUMEROUS IN THE
SOUTHEAST CWA AS DEPICTED WELL BY EARLIER FORECASTS AND RECENT HRRR
MODEL RUNS. DEEP LAYER BULK SHEAR IS QUITE WEAK THOUGH WITH MARGINAL
D-CAPE... SO ANY PARTICULARLY STRONG STORMS SHOULD REMAIN
ISOLATED... BUT MIXED-PHASE CAPE AROUND 700 J/KG AND INCREASING
MOISTURE IN THE -10C TO -30C LAYER ACCORDING TO RAP FORECAST
SOUNDINGS SUGGESTS A THREAT OF SMALL HAIL WITH ANY STRONG CELL...
AND CERTAINLY LOCALLY HEAVY DOWNPOURS REMAIN A CONCERN GIVEN THE
SLOW MOVEMENT AND INCREASING PW. LOSS OF HEATING AS WELL AS THE
PASSAGE OF THE WEAK WAVE EAST OF THE AREA SHOULD BRING A GRADUAL
DISSIPATION OF CONVECTION BY CLOSE TO MIDNIGHT. FOLLOWING
PERSISTENCE WITH NO SIGNIFICANT CHANGE IN AIR MASS... REDEVELOPMENT
OF STRATUS IS ANTICIPATED ACROSS THE AREA LATE TONIGHT... WITH A
LINGERING THREAT OF ISOLATED SHALLOW SHOWERS MAINLY IN THE SOUTH AND
EAST WHERE ABUNDANT LOW LEVEL MOISTURE PERSISTS. LOWS CLOSE TO LAST
NIGHT... 70-74. -GIH
&&
.SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/...
AS OF 240 PM TUESDAY...
FOR WEDNESDAY/WEDNESDAY NIGHT: LOOKS LIKE MORE OF THE SAME... WITH A
CONTINUED HUMID AIR MASS AND MOIST COLUMN FEATURING PW VALUES OF
1.7-1.9 INCHES IN THE MORNING CLIMBING TO 1.9-2.1 INCHES IN THE
AFTERNOON... HIGHEST EAST. WEAK LEE SURFACE TROUGHING HOLDS IN PLACE
WITH A CONTINUATION OF LIGHT BREEZES FROM THE SW... WHILE IN THE MID
LEVELS... VERY WEAK FLOW FROM THE WNW NEAR THE ILL-DEFINED SHEAR
AXIS ALOFT WILL ALLOW FOR LITTLE TO NO DYNAMIC FORCING FOR ASCENT
THROUGH THE AFTERNOON... ALTHOUGH THIS FLOW DOES INCREASE SLIGHTLY
IN THE EVENING AND OVERNIGHT HOURS AS A STRONG WAVE DIGS INTO THE
MEAN TROUGH OVER THE GREAT LAKES. MLCAPE ONCE AGAIN SHOULD TOP OUT
AROUND 1500-2500 J/KG BUT WITH CONTINUED LOW DEEP-LAYER BULK SHEAR
OF JUST 10-15 KTS... SO EXPECT ANOTHER ROUND OF SCATTERED STORMS
WITH DESTABILIZATION... WITH HIGHEST POPS IN THE WRN CWA WHERE THE
SREF INDICATES THE BEST CHANCE OF MEASURABLE RAIN... BUT ANY STORMS
SHOULD HOLD BELOW SEVERE LIMITS. WILL RETAIN A MENTION OF ISOLATED
SHOWERS OVERNIGHT WITH THE IMPROVING FLOW ALOFT AND LINGERING LOW
LEVEL MOISTURE. HIGHS 86-90 AND LOWS AGAIN 70-74. -GIH
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 225 AM TUESDAY...
THURSDAY THROUGH FRIDAY IS EXPECTED TO BE A WET PERIOD ONCE AGAIN.
THE APPROACH OF ANOTHER MID/UPPER TROUGH FROM THE NW COMBINED WITH
THE SURFACE COLD FRONT SETTLING INTO LOWER TO MID 70S DEW POINTS
WILL SET THE STAGE FOR YET ANOTHER COUPLE OF DAYS WITH WIDESPREAD
CONVECTIVE RAINS. THE HIGHEST POP IS EXPECTED ON THURSDAY OVER THE
PIEDMONT INTO PORTIONS OF THE COASTAL PLAIN AND SANDHILLS BY LATE
AFTERNOON/EVENING. CONVECTIVE DEVELOPMENT THURSDAY SHOULD BE AIDED
BY THE LEE TROUGH AND DIFFERENTIAL HEATING ALONG THE MOUNTAINS. THE
FORMER SHOULD RESULT IN GOOD LOW LEVEL CONVERGENCE WITH PRECIPITABLE
WATER VALUES INCREASING TO BETWEEN 1.8 AND 2 INCHES FAVORING HEAVY
RAINERS SPREADING OFF THE BLUE RIDGE OUT OVER THE PIEDMONT BY EARLY
AFTERNOON. ADDITIONAL DEVELOPMENT SHOULD OCCUR ALONG THE LEE TROUGH
AND NUMEROUS CONVECTIVE OUTFLOWS DURING THE MID TO LATE AFTERNOON
EASTWARD THROUGH THE PIEDMONT AND COASTAL PLAIN. SINCE CATEGORICAL
POP ARE IN PLACE... NO NEED FOR ADJUSTMENTS. QPF OF 1 TO LOCALLY 2
INCHES EXPECTED 12Z THU THROUGH 12 FRI.
THE HEAVY RAIN THREAT WITH DEEP CONVECTION SHOULD SHIFT SLOWLY SE
THROUGH THE REGION REACHING THE SANDHILLS AND COASTAL PLAIN THURSDAY
NIGHT... WHILE LINGERING IN THE PIEDMONT. THEN FRIDAY... NUMEROUS
SHOWERS AND THUNDERSTORMS WILL AGAIN DEVELOP... ALONG AND AHEAD OF
THE LEFT-OVER CONVECTIVE BOUNDARIES/COLD FRONT. IT APPEARS THAT THE
NW PIEDMONT SHOULD HAVE THE LOWER POP (BUT STILL IN THE LIKELY RANGE
FRIDAY). TO THE EAST AND SOUTH... THROUGH MUCH OF CENTRAL AND
EASTERN NC... NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED AS THE
COLD FRONT SLOWS TO A CRAWL... FOCUSING HIGH PW`S OF 2+ INCHES...
AND LOW LEVEL CONVERGENCE. QPF OF 1.5 TO 2 INCHES LOOKS A GOOD
BET... WITH LOCALLY HIGHER TOTALS. THIS WOULD GIVE QPF 2 DAY TOTALS
OF 2 TO 4 INCHES... NOT WHAT AGRICULTURAL INTERESTS NEED AT THIS
POINT.
FRIDAY NIGHT AND SATURDAY... THE COLD FRONT SHOULD STALL OVER THE
COASTAL PLAIN... WHERE THE HIGHEST POP WILL RESIDE. LOCALLY HEAVY
RAIN THREAT WILL CONTINUE. NUMEROUS SHOWERS AND THUNDERSTORMS SHOULD
BECOME MORE SCATTERED BY SATURDAY ACROSS THE NW PIEDMONT (AWAY FROM
THE STALLED BOUNDARY TO THE SE). LOWS 70-73. HIGHS LOWER TO MID 80S.
SUNDAY AND MONDAY... THE FOCUS TURNS TO THE EVOLUTION OF TS CHANTAL.
IT APPEARS THAT THE BEST FORECAST FOR OUR REGION WOULD BE TO FOLLOW
THE ENSEMBLE MEANS AND MODEL TRENDS. THE ANTECEDENT VERY WET
CONDITIONS OVER OUR REGION CERTAINLY WOULD BE PROBLEMATIC TO SAY THE
LEAST SHOULD CHANTAL BECOME AN ISSUE FOR NC.
HOWEVER... THE ENSEMBLES GENERALLY TURN WHAT IS LEFT OF THIS SYSTEM
WESTWARD AS HEIGHTS ARE FORECAST TO RISE ALONG THE EAST COAST FROM
BUILDING WESTERN ATLANTIC RIDGING BY SUNDAY AND MONDAY. AS OF THIS
FORECAST... IT APPEARS THAT MID/UPPER RIDGING OVER THE WESTERN
ATLANTIC MAY BUILD WESTWARD INTO EASTERN NC ENOUGH TO STEER THIS
SYSTEM WESTWARD (GULF COAST) BY SUNDAY AND MONDAY. THIS WOULD ALLOW
THE NUMEROUS SHOWERS AND STORMS TO BECOME SCATTERED... MAINLY
DIURNALLY DRIVEN SHOWERS AND THUNDERSTORMS SUNDAY AND MONDAY FOR OUR
REGION. HIGHS WOULD ALSO GO UP TO NEAR NORMAL BY THEN AS WELL. LOWS
70-73. HIGHS 85-88.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 1245 PM TUESDAY...
MVFR CIGS WILL CONTINUE TO COME AND GO AT CENTRAL NC TAF SITES
THROUGH 20Z AS CLOUDS BASED AT 1-3 THOUSAND FT WILL VARY BETWEEN
SCATTERED AND BROKEN. EXPECT VFR CIGS AFTER 20Z. NUMEROUS SHOWERS
AND STORMS ARE EXPECTED BETWEEN 20Z AND 03Z WITH BEST COVERAGE NEAR
FAY/RWI... FEWER SHOWERS/STORMS AT RDU AND EVEN FEWER (SCATTERED AT
MOST) AT INT/GSO. IN/NEAR THESE STORMS... MVFR/IFR CIGS/VSBYS AND
BRIEF WIND GUSTS OVER 30 MPH ARE POSSIBLE. OTHERWISE... VFR
CONDITIONS AND LIGHT WINDS FROM THE SOUTH OR SW (UNDER 12 KTS) WILL
DOMINATE UNTIL AROUND 07Z... WHEN IFR STRATUS IS EXPECTED TO DEVELOP
ONCE AGAIN... AS HAS OCCURRED ON PREVIOUS MORNINGS. CIGS SHOULD LIFT
SLOWLY TO MVFR BY 16Z-18Z.
LOOKING BEYOND 18Z WEDNESDAY... CIGS ARE EXPECTED TO TREND TO VFR
18Z-20Z WEDNESDAY WITH SCATTERED STORMS DEVELOPING. IFR CONDITIONS
ARE LIKELY TO RETURN AFTER 07Z THURSDAY THROUGH MID MORNING...
LIFTING SLOWLY TO MVFR THEN VFR BY EARLY THURSDAY AFTERNOON.
OCCASIONALLY MVFR CONDITIONS ARE LIKELY WITH NUMEROUS SHOWERS AND
STORMS THURSDAY AFTERNOON THROUGH FRIDAY. MVFR CONDITIONS COULD
LINGER AT FAY THROUGH SUNDAY... BUT OTHERWISE VFR CONDITIONS ARE
EXPECTED TO DOMINATE FRIDAY NIGHT THROUGH SUNDAY... ALTHOUGH IFR
STRATUS IS AGAIN LIKELY 07Z-14Z SUNDAY MORNING. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...BADGETT
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1245 PM EDT TUE JUL 9 2013
.SYNOPSIS...
A WEAK UPPER LEVEL LOW PRESSURE TROUGH WILL HOLD OVER THE EASTERN
U.S. THROUGH WEDNESDAY. A STRONGER UPPER LEVEL TROUGH AND ASSOCIATED
SURFACE COLD FRONT WILL APPROACH THE AREA FROM THE NORTHEAST LATE
WEDNESDAY... AND SWING THROUGH THE REGION THURSDAY THROUGH FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 940 AM TUESDAY...
REST OF TODAY THROUGH TONIGHT: QUITE A BIT OF STRATUS (ABOUT 500 FT
THICK ACCORDING TO PILOT REPORTS) IS HOLDING OVER THE AREA...
PARTICULARY NRN/WRN AREAS. WATER VAPOR IMAGERY SHOWS A SUBTLE
VORTICITY MAX DROPPING THROUGH CENTRAL VA INTO NRN NC... ON THE
HEELS OF ANOTHER WAVE NOW SUPPORTING SLOW-MOVING THUNDERSTORM
CLUSTERS NEAR THE COAST. THE LATEST HRRR RUNS SHOW SCATTERED TO
NUMEROUS STORMS DEVELOPING OVER THE SRN/ERN PORTIONS OF THE FORECAST
AREA... PERHAPS A RESPONSE TO BOTH GREATER HEATING IN THIS AREA THIS
MORNING AND THE PASSAGE OF THIS WEAK WAVE. CURRENT FORECAST... WITH
MINOR ADJUSTMENTS IN TIMING AND AREA... HINTS AT THIS SCENARIO AND
LOOKS VERY REASONABLE GIVEN THE SHORT TERM TRENDS. CINH IS QUICKLY
ERODING WITH MLCAPE ALREADY AT 1500 J/KG... BUT WITH LOW DEEP-LAYER
BULK SHEAR AND MEANDERING MOVEMENT... STORMS SHOULD STAY BELOW
SEVERE LIMITS... BUT THE RISK OF LOCALLY HEAVY DOWNPOURS WILL
PERSIST. LOW LEVEL THICKNESSES FAVOR HIGHS IN THE UPPER 80S... IN
LINE WITH LATEST STATISTICAL GUIDANCE AND EXISTING FORECAST...
FACTORING IN VARIABLY CLOUDY SKIES. -GIH
THOUGH COVERAGE AND INTENSITY SHOULD DIMINISH WITH NOCTURNAL
COOLING...THE VERY MOIST AND WEAKLY CONDITIONALLY UNSTABLE AIR MASS
OVERNIGHT WILL LIKELY SUPPORT A FEW SHOWERS. LOWS IN THE LOWER 70S.
-MWS
&&
.SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/...
AS OF 315 AM TUESDAY...
WEDNESDAY AND WEDNESDAY NIGHT: PERSISTENCE OVERALL...WITH CONTINUED
BERMUDA HIGH PRESSURE EXTENDING WESTWARD INTO THE CAROLINAS...
BENEATH TROUGHING/CYCLONIC FLOW IN THE MID LEVELS. THIS
PATTERN...AMIDST A VERY MOIST AND UNCAPPED BOUNDARY LAYER...SHOULD
AGAIN PRODUCE SCATTERED SHOWERS AND STORMS MAXIMIZED WITH DIURNAL
HEATING. IN ADDITION...GULF MOISTURE...WHICH WILL HAVE BEEN
PREVIOUSLY LIMITED OWING TO RIDGING OVER THE GOM AND GULF COAST
STATES...WILL HAVE CIRCUMVENTED THE RIDGE AND ARRIVE IN
STRENGTHENING H85 WESTERLY FLOW LATE WED AND ESPECIALLY WED NIGHT.
THIS REGIME...AS WELL AS INCREASING HEIGHT FALLS ALOFT DOWNSTREAM OF
A POWERFUL TROUGH AMPLIFYING THROUGH THE GREAT LAKES...MAY SUPPORT
ADDITIONAL CONVECTION OVERNIGHT...MAINLY OVER THE WESTERN PIEDMONT
WHERE THE EFFECTS OF THE MOISTURE TRANSPORT/ISENTROPIC UPGLIDE WILL
OCCUR FIRST. PERSISTENCE TEMPS IN THE UPPER 80S TO AROUND 90...AND
LOWER 70S.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 225 AM TUESDAY...
THURSDAY THROUGH FRIDAY IS EXPECTED TO BE A WET PERIOD ONCE AGAIN.
THE APPROACH OF ANOTHER MID/UPPER TROUGH FROM THE NW COMBINED WITH
THE SURFACE COLD FRONT SETTLING INTO LOWER TO MID 70S DEW POINTS
WILL SET THE STAGE FOR YET ANOTHER COUPLE OF DAYS WITH WIDESPREAD
CONVECTIVE RAINS. THE HIGHEST POP IS EXPECTED ON THURSDAY OVER THE
PIEDMONT INTO PORTIONS OF THE COASTAL PLAIN AND SANDHILLS BY LATE
AFTERNOON/EVENING. CONVECTIVE DEVELOPMENT THURSDAY SHOULD BE AIDED
BY THE LEE TROUGH AND DIFFERENTIAL HEATING ALONG THE MOUNTAINS. THE
FORMER SHOULD RESULT IN GOOD LOW LEVEL CONVERGENCE WITH PRECIPITABLE
WATER VALUES INCREASING TO BETWEEN 1.8 AND 2 INCHES FAVORING HEAVY
RAINERS SPREADING OFF THE BLUE RIDGE OUT OVER THE PIEDMONT BY EARLY
AFTERNOON. ADDITIONAL DEVELOPMENT SHOULD OCCUR ALONG THE LEE TROUGH
AND NUMEROUS CONVECTIVE OUTFLOWS DURING THE MID TO LATE AFTERNOON
EASTWARD THROUGH THE PIEDMONT AND COASTAL PLAIN. SINCE CATEGORICAL
POP ARE IN PLACE... NO NEED FOR ADJUSTMENTS. QPF OF 1 TO LOCALLY 2
INCHES EXPECTED 12Z THU THROUGH 12 FRI.
THE HEAVY RAIN THREAT WITH DEEP CONVECTION SHOULD SHIFT SLOWLY SE
THROUGH THE REGION REACHING THE SANDHILLS AND COASTAL PLAIN THURSDAY
NIGHT... WHILE LINGERING IN THE PIEDMONT. THEN FRIDAY... NUMEROUS
SHOWERS AND THUNDERSTORMS WILL AGAIN DEVELOP... ALONG AND AHEAD OF
THE LEFT-OVER CONVECTIVE BOUNDARIES/COLD FRONT. IT APPEARS THAT THE
NW PIEDMONT SHOULD HAVE THE LOWER POP (BUT STILL IN THE LIKELY RANGE
FRIDAY). TO THE EAST AND SOUTH... THROUGH MUCH OF CENTRAL AND
EASTERN NC... NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED AS THE
COLD FRONT SLOWS TO A CRAWL... FOCUSING HIGH PW`S OF 2+ INCHES...
AND LOW LEVEL CONVERGENCE. QPF OF 1.5 TO 2 INCHES LOOKS A GOOD
BET... WITH LOCALLY HIGHER TOTALS. THIS WOULD GIVE QPF 2 DAY TOTALS
OF 2 TO 4 INCHES... NOT WHAT AGRICULTURAL INTERESTS NEED AT THIS
POINT.
FRIDAY NIGHT AND SATURDAY... THE COLD FRONT SHOULD STALL OVER THE
COASTAL PLAIN... WHERE THE HIGHEST POP WILL RESIDE. LOCALLY HEAVY
RAIN THREAT WILL CONTINUE. NUMEROUS SHOWERS AND THUNDERSTORMS SHOULD
BECOME MORE SCATTERED BY SATURDAY ACROSS THE NW PIEDMONT (AWAY FROM
THE STALLED BOUNDARY TO THE SE). LOWS 70-73. HIGHS LOWER TO MID 80S.
SUNDAY AND MONDAY... THE FOCUS TURNS TO THE EVOLUTION OF TS CHANTAL.
IT APPEARS THAT THE BEST FORECAST FOR OUR REGION WOULD BE TO FOLLOW
THE ENSEMBLE MEANS AND MODEL TRENDS. THE ANTECEDENT VERY WET
CONDITIONS OVER OUR REGION CERTAINLY WOULD BE PROBLEMATIC TO SAY THE
LEAST SHOULD CHANTAL BECOME AN ISSUE FOR NC.
HOWEVER... THE ENSEMBLES GENERALLY TURN WHAT IS LEFT OF THIS SYSTEM
WESTWARD AS HEIGHTS ARE FORECAST TO RISE ALONG THE EAST COAST FROM
BUILDING WESTERN ATLANTIC RIDGING BY SUNDAY AND MONDAY. AS OF THIS
FORECAST... IT APPEARS THAT MID/UPPER RIDGING OVER THE WESTERN
ATLANTIC MAY BUILD WESTWARD INTO EASTERN NC ENOUGH TO STEER THIS
SYSTEM WESTWARD (GULF COAST) BY SUNDAY AND MONDAY. THIS WOULD ALLOW
THE NUMEROUS SHOWERS AND STORMS TO BECOME SCATTERED... MAINLY
DIURNALLY DRIVEN SHOWERS AND THUNDERSTORMS SUNDAY AND MONDAY FOR OUR
REGION. HIGHS WOULD ALSO GO UP TO NEAR NORMAL BY THEN AS WELL. LOWS
70-73. HIGHS 85-88.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 1245 PM TUESDAY...
MVFR CIGS WILL CONTINUE TO COME AND GO AT CENTRAL NC TAF SITES
THROUGH 20Z AS CLOUDS BASED AT 1-3 THOUSAND FT WILL VARY BETWEEN
SCATTERED AND BROKEN. EXPECT VFR CIGS AFTER 20Z. NUMEROUS SHOWERS
AND STORMS ARE EXPECTED BETWEEN 20Z AND 03Z WITH BEST COVERAGE NEAR
FAY/RWI... FEWER SHOWERS/STORMS AT RDU AND EVEN FEWER (SCATTERED AT
MOST) AT INT/GSO. IN/NEAR THESE STORMS... MVFR/IFR CIGS/VSBYS AND
BRIEF WIND GUSTS OVER 30 MPH ARE POSSIBLE. OTHERWISE... VFR
CONDITIONS AND LIGHT WINDS FROM THE SOUTH OR SW (UNDER 12 KTS) WILL
DOMINATE UNTIL AROUND 07Z... WHEN IFR STRATUS IS EXPECTED TO DEVELOP
ONCE AGAIN... AS HAS OCCURRED ON PREVIOUS MORNINGS. CIGS SHOULD LIFT
SLOWLY TO MVFR BY 16Z-18Z.
LOOKING BEYOND 18Z WEDNESDAY... CIGS ARE EXPECTED TO TREND TO VFR
18Z-20Z WEDNESDAY WITH SCATTERED STORMS DEVELOPING. IFR CONDITIONS
ARE LIKELY TO RETURN AFTER 07Z THURSDAY THROUGH MID MORNING...
LIFTING SLOWLY TO MVFR THEN VFR BY EARLY THURSDAY AFTERNOON.
OCCASIONALLY MVFR CONDITIONS ARE LIKELY WITH NUMEROUS SHOWERS AND
STORMS THURSDAY AFTERNOON THROUGH FRIDAY. MVFR CONDITIONS COULD
LINGER AT FAY THROUGH SUNDAY... BUT OTHERWISE VFR CONDITIONS ARE
EXPECTED TO DOMINATE FRIDAY NIGHT THROUGH SUNDAY... ALTHOUGH IFR
STRATUS IS AGAIN LIKELY 07Z-14Z SUNDAY MORNING. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD/MWS
SHORT TERM...MWS
LONG TERM...BADGETT
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
940 AM EDT TUE JUL 9 2013
.SYNOPSIS...
A WEAK UPPER LEVEL LOW PRESSURE TROUGH WILL HOLD OVER THE EASTERN
U.S. THROUGH WEDNESDAY. A STRONGER UPPER LEVEL TROUGH AND ASSOCIATED
SURFACE COLD FRONT WILL APPROACH THE AREA FROM THE NORTHEAST LATE
WEDNESDAY... AND SWING THROUGH THE REGION THURSDAY THROUGH FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 940 AM TUESDAY...
REST OF TODAY THROUGH TONIGHT: QUITE A BIT OF STRATUS (ABOUT 500 FT
THICK ACCORDING TO PILOT REPORTS) IS HOLDING OVER THE AREA...
PARTICULARY NRN/WRN AREAS. WATER VAPOR IMAGERY SHOWS A SUBTLE
VORTICITY MAX DROPPING THROUGH CENTRAL VA INTO NRN NC... ON THE
HEELS OF ANOTHER WAVE NOW SUPPORTING SLOW-MOVING THUNDERSTORM
CLUSTERS NEAR THE COAST. THE LATEST HRRR RUNS SHOW SCATTERED TO
NUMEROUS STORMS DEVELOPING OVER THE SRN/ERN PORTIONS OF THE FORECAST
AREA... PERHAPS A RESPONSE TO BOTH GREATER HEATING IN THIS AREA THIS
MORNING AND THE PASSAGE OF THIS WEAK WAVE. CURRENT FORECAST... WITH
MINOR ADJUSTMENTS IN TIMING AND AREA... HINTS AT THIS SCENARIO AND
LOOKS VERY REASONABLE GIVEN THE SHORT TERM TRENDS. CINH IS QUICKLY
ERODING WITH MLCAPE ALREADY AT 1500 J/KG... BUT WITH LOW DEEP-LAYER
BULK SHEAR AND MEANDERING MOVEMENT... STORMS SHOULD STAY BELOW
SEVERE LIMITS... BUT THE RISK OF LOCALLY HEAVY DOWNPOURS WILL
PERSIST. LOW LEVEL THICKNESSES FAVOR HIGHS IN THE UPPER 80S... IN
LINE WITH LATEST STATISTICAL GUIDANCE AND EXISTING FORECAST...
FACTORING IN VARIABLY CLOUDY SKIES. -GIH
THOUGH COVERAGE AND INTENSITY SHOULD DIMINISH WITH NOCTURNAL
COOLING...THE VERY MOIST AND WEAKLY CONDITIONALLY UNSTABLE AIR MASS
OVERNIGHT WILL LIKELY SUPPORT A FEW SHOWERS. LOWS IN THE LOWER 70S.
-MWS
&&
.SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/...
AS OF 315 AM TUESDAY...
WEDNESDAY AND WEDNESDAY NIGHT: PERSISTENCE OVERALL...WITH CONTINUED
BERMUDA HIGH PRESSURE EXTENDING WESTWARD INTO THE CAROLINAS...
BENEATH TROUGHING/CYCLONIC FLOW IN THE MID LEVELS. THIS
PATTERN...AMIDST A VERY MOIST AND UNCAPPED BOUNDARY LAYER...SHOULD
AGAIN PRODUCE SCATTERED SHOWERS AND STORMS MAXIMIZED WITH DIURNAL
HEATING. IN ADDITION...GULF MOISTURE...WHICH WILL HAVE BEEN
PREVIOUSLY LIMITED OWING TO RIDGING OVER THE GOM AND GULF COAST
STATES...WILL HAVE CIRCUMVENTED THE RIDGE AND ARRIVE IN
STRENGTHENING H85 WESTERLY FLOW LATE WED AND ESPECIALLY WED NIGHT.
THIS REGIME...AS WELL AS INCREASING HEIGHT FALLS ALOFT DOWNSTREAM OF
A POWERFUL TROUGH AMPLIFYING THROUGH THE GREAT LAKES...MAY SUPPORT
ADDITIONAL CONVECTION OVERNIGHT...MAINLY OVER THE WESTERN PIEDMONT
WHERE THE EFFECTS OF THE MOISTURE TRANSPORT/ISENTROPIC UPGLIDE WILL
OCCUR FIRST. PERSISTENCE TEMPS IN THE UPPER 80S TO AROUND 90...AND
LOWER 70S.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 225 AM TUESDAY...
THURSDAY THROUGH FRIDAY IS EXPECTED TO BE A WET PERIOD ONCE AGAIN.
THE APPROACH OF ANOTHER MID/UPPER TROUGH FROM THE NW COMBINED WITH
THE SURFACE COLD FRONT SETTLING INTO LOWER TO MID 70S DEW POINTS
WILL SET THE STAGE FOR YET ANOTHER COUPLE OF DAYS WITH WIDESPREAD
CONVECTIVE RAINS. THE HIGHEST POP IS EXPECTED ON THURSDAY OVER THE
PIEDMONT INTO PORTIONS OF THE COASTAL PLAIN AND SANDHILLS BY LATE
AFTERNOON/EVENING. CONVECTIVE DEVELOPMENT THURSDAY SHOULD BE AIDED
BY THE LEE TROUGH AND DIFFERENTIAL HEATING ALONG THE MOUNTAINS. THE
FORMER SHOULD RESULT IN GOOD LOW LEVEL CONVERGENCE WITH PRECIPITABLE
WATER VALUES INCREASING TO BETWEEN 1.8 AND 2 INCHES FAVORING HEAVY
RAINERS SPREADING OFF THE BLUE RIDGE OUT OVER THE PIEDMONT BY EARLY
AFTERNOON. ADDITIONAL DEVELOPMENT SHOULD OCCUR ALONG THE LEE TROUGH
AND NUMEROUS CONVECTIVE OUTFLOWS DURING THE MID TO LATE AFTERNOON
EASTWARD THROUGH THE PIEDMONT AND COASTAL PLAIN. SINCE CATEGORICAL
POP ARE IN PLACE... NO NEED FOR ADJUSTMENTS. QPF OF 1 TO LOCALLY 2
INCHES EXPECTED 12Z THU THROUGH 12 FRI.
THE HEAVY RAIN THREAT WITH DEEP CONVECTION SHOULD SHIFT SLOWLY SE
THROUGH THE REGION REACHING THE SANDHILLS AND COASTAL PLAIN THURSDAY
NIGHT... WHILE LINGERING IN THE PIEDMONT. THEN FRIDAY... NUMEROUS
SHOWERS AND THUNDERSTORMS WILL AGAIN DEVELOP... ALONG AND AHEAD OF
THE LEFT-OVER CONVECTIVE BOUNDARIES/COLD FRONT. IT APPEARS THAT THE
NW PIEDMONT SHOULD HAVE THE LOWER POP (BUT STILL IN THE LIKELY RANGE
FRIDAY). TO THE EAST AND SOUTH... THROUGH MUCH OF CENTRAL AND
EASTERN NC... NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED AS THE
COLD FRONT SLOWS TO A CRAWL... FOCUSING HIGH PW`S OF 2+ INCHES...
AND LOW LEVEL CONVERGENCE. QPF OF 1.5 TO 2 INCHES LOOKS A GOOD
BET... WITH LOCALLY HIGHER TOTALS. THIS WOULD GIVE QPF 2 DAY TOTALS
OF 2 TO 4 INCHES... NOT WHAT AGRICULTURAL INTERESTS NEED AT THIS
POINT.
FRIDAY NIGHT AND SATURDAY... THE COLD FRONT SHOULD STALL OVER THE
COASTAL PLAIN... WHERE THE HIGHEST POP WILL RESIDE. LOCALLY HEAVY
RAIN THREAT WILL CONTINUE. NUMEROUS SHOWERS AND THUNDERSTORMS SHOULD
BECOME MORE SCATTERED BY SATURDAY ACROSS THE NW PIEDMONT (AWAY FROM
THE STALLED BOUNDARY TO THE SE). LOWS 70-73. HIGHS LOWER TO MID 80S.
SUNDAY AND MONDAY... THE FOCUS TURNS TO THE EVOLUTION OF TS CHANTAL.
IT APPEARS THAT THE BEST FORECAST FOR OUR REGION WOULD BE TO FOLLOW
THE ENSEMBLE MEANS AND MODEL TRENDS. THE ANTECEDENT VERY WET
CONDITIONS OVER OUR REGION CERTAINLY WOULD BE PROBLEMATIC TO SAY THE
LEAST SHOULD CHANTAL BECOME AN ISSUE FOR NC.
HOWEVER... THE ENSEMBLES GENERALLY TURN WHAT IS LEFT OF THIS SYSTEM
WESTWARD AS HEIGHTS ARE FORECAST TO RISE ALONG THE EAST COAST FROM
BUILDING WESTERN ATLANTIC RIDGING BY SUNDAY AND MONDAY. AS OF THIS
FORECAST... IT APPEARS THAT MID/UPPER RIDGING OVER THE WESTERN
ATLANTIC MAY BUILD WESTWARD INTO EASTERN NC ENOUGH TO STEER THIS
SYSTEM WESTWARD (GULF COAST) BY SUNDAY AND MONDAY. THIS WOULD ALLOW
THE NUMEROUS SHOWERS AND STORMS TO BECOME SCATTERED... MAINLY
DIURNALLY DRIVEN SHOWERS AND THUNDERSTORMS SUNDAY AND MONDAY FOR OUR
REGION. HIGHS WOULD ALSO GO UP TO NEAR NORMAL BY THEN AS WELL. LOWS
70-73. HIGHS 85-88.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 745 AM TUESDAY...
CONTINUED VERY HUMID SOUTHERLY FLOW AROUND BERMUDA HIGH PRESSURE
WILL MAINTAIN A FAMILIAR...PERSISTENT PATTERN. THAT IS...LIFR-IFR
CEILINGS AND VFR-MVFR VISIBILITY RESTRICTIONS TRANSITIONING THROUGH
MVFR RANGE TO VFR BETWEEN 13-15Z...WITH MOSTLY AFTERNOON-EVENING
THUNDERSTORMS...MOST LIKELY TODAY AT KFAY/KRWI/KRDU. LIFR-IFR
CEILINGS AND MVFR VISIBILITY RESTRICTIONS WILL THEN REDEVELOP IN THE
VERY HUMID REGIME LATE TONIGHT.
OUTLOOK...
INCREASED SHOWER AND STORM COVERAGE...AND MORE PROLONGED
MVFR CONDITIONS THAN PREVIOUS DAYS - INTO EARLY AFTERNOON - WILL
DEVELOP BY FRI-SAT...AS A STRONG UPPER LEVEL TROUGH AND SURFACE COLD
FRONT MOVE INTO OUR REGION.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD/MWS
SHORT TERM...MWS
LONG TERM...BADGETT
AVIATION...MWS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1254 AM CDT TUE JUL 9 2013
.UPDATE...
ISSUED AT 1254 AM CDT TUE JUL 9 2013
SEVERE TSTM WATCH 402 HAS EXPIRED...AND ALSO CANCELLED WATCH 403
FOR 4 COUNTIES IN NORTH CENTRAL NORTH DAKOTA. WATCH 403 REMAINS
VALID UNTIL 4 AM CDT FOR A LINE FROM EMMONS TO WELLS COUNTIES AND
EASTWARD. EXPECT TO BE ABLE TO DROP THESE COUNTIES IN THE NEXT
HOUR OR 2 AS SEVERE LINE MOVES THROUGH.
UPDATE ISSUED AT 1150 PM CDT MON JUL 8 2013
WILL LEAVE SEVERE T-STORM WATCH 403 AS IS FOR NOW. WILL EXTEND SVR
WATCH 402 FOR MORTON...GRANT...AND SIOUX COUNTIES FOR ONE MORE
HOUR WITH A LINE OF STORMS MOVING ACROSS THOSE COUNTIES RIGHT NOW.
WHILE THE THREAT APPEARS LOW WITH THE BETTER SEVERE PARAMETERS IN
SOUTH DAKOTA...FIGURE ONE MORE HOUR WILL NOT HURT...WHEN PERHAPS
PART OF 403 CAN BE LET GO AS WELL.
UPDATED PRODUCTS OUT SHORTLY.
UPDATE ISSUED AT 1013 PM CDT MON JUL 8 2013
UPDATED THE FORECAST TO EXTEND THE SEVERE THUNDERSTORM WATCH EAST
INTO THE JAMES RIVER VALLEY.
MCS OVER WEST CENTRAL NORTH DAKOTA DEVELOPED INTO AN MCV IN THE
LAST HOUR OR TWO. THE LEADING EDGE OF THIS ACTIVITY HAS BEEN
PRODUCING WIDESPREAD WIND GUSTS UP TO 60 MPH. THIS ACTIVITY WILL
CONTINUE TO PUSH EAST INTO THE JAMES RIVER VALLEY AFTER MIDNIGHT.
ANOTHER BOW ECHO IS PUSHING EAST ACROSS SOUTHWESTERN NORTH DAKOTA.
ITS STORM MOTION HAS BEEN EAST-SOUTHEAST AND WILL LIKELY CONTINUE
TO PUSH INTO SOUTH DAKOTA DURING THE NEXT FEW HOURS.
THE UPDATED PRODUCTS HAVE BEEN SENT.
UPDATE ISSUED AT 703 PM CDT MON JUL 8 2013
UPDATED THE FORECAST TO ADD SEVERE THUNDERSTORM WATCH 402 FOR
AREAS WEST OF HIGHWAY 83.
ONGOING CONVECTION OVER EAST-CENTRAL MONTANA SHOULD CONTINUE TO
MOVE EAST-SOUTHEAST INTO SOUTHWESTERN NORTH DAKOTA EARLY THIS
EVENING. THIS ACTIVITY IS CONGEALING INTO AN MCS AND IS MOVING
INTO A FAVORABLE ENVIRONMENT FOR MCS MAINTENANCE (SURFACE BASED
CAPE AROUND 2000 J/KG PER LATEST LAPS ANALYSIS). THIS INITIAL
CONVECTIVE ACTIVITY PROMPTED SPC TO ISSUE A SEVERE THUNDERSTORM
WATCH FOR AREAS WEST OF HIGHWAY 83 UNTIL MIDNIGHT CDT.
SHORT-RANGE MESOSCALE MODELS CONTINUE TO PROG THE PRIMARY LINE
OF CONVECTION (CURRENTLY EXTENDING FROM GLASGOW TO BILLINGS) TO
PUSH INTO WESTERN NORTH DAKOTA AROUND 03Z...AND SWEEP ACROSS THE
CWA TONIGHT. THE FLY IN THE OINTMENT IS JUST HOW MUCH INSTABILITY
THE INITIAL MCS CHEWS UP BEFORE THE PRIMARY LINE SWINGS THROUGH.
STILL WILL MAINTAIN SEVERE WORDING PAST MIDNIGHT FOR CENTRAL NORTH
DAKOTA. HOWEVER...WILL CONTINUE TO MONITOR EVENING TRENDS AND
MAKE ANY ADJUSTMENTS AS NEEDED. THE UPDATED GRIDDED AND TEXT
PRODUCTS HAVE BEEN SENT.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 341 PM CDT MON JUL 8 2013
THE MAIN FORECAST ISSUE DURING THE SHORT TERM IS STORM
COVERAGE/TIMING/SEVERITY THROUGH TONIGHT. SCATTERED STORMS ARE
EXPECTED TO DEVELOP AND/OR MOVE INTO THE WEST LATE THIS AFTERNOON.
MORE FAVORABLE DEEP LAYER SHEAR IS CONFINED TO THE WEST THROUGH
LATE AFTERNOON. SOME ISOLATED SEVERE STORMS ARE POSSIBLE...WITH
LARGE HAIL THE MAIN THREAT. THE HRRR IS STILL FOCUSING ON THE SOUTHWEST
FOR INITIATION...WHILE THE 12Z WRF FOCUSES ON A FRONT STRETCHING
FROM WEST CENTRAL INTO NORTH CENTRAL NORTH DAKOTA. WILL CONTINUE
TO MONITOR CLOSELY FOR INITIATION. AN INTENSE SUPERCELL IS MOVING
THROUGH NORTHEAST MONTANA...AND WOULD IMPACT THE FORECAST AREA
AFTER 00Z IF IT HOLDS TOGETHER. A BIGGER CONCERN WILL BE A
THUNDERSTORM COMPLEX THAT WILL LIKELY TRACK FROM WEST TO EAST
ACROSS THE FORECAST AREA AFTER AROUND 9 PM CDT. DAMAGING STRAIGHT
LINE WINDS WILL BE THE BIGGEST THREAT. FAST STORM MOTIONS SHOULD
PRECLUDE WIDESPREAD FLASH FLOODING. A MULTI- MEDIA WEATHER BRIEFING
HAS BEEN POSTED AT WWW.WEATHER.GOV/BIS. THE SEVERE THREAT MAY
PERSIST AFTER MIDNIGHT TONIGHT BEFORE STORMS WEAKEN. ADDITIONAL
NON-SEVERE STORMS WILL BE LIKELY THROUGH AT LEAST MIDDAY TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 341 PM CDT MON JUL 8 2013
MAIN HIGHLIGHT FOR THE LONG TERM IS SHORTWAVE TROUGH AND
ASSOCIATED COLD FRONT ENTERING NORTHERN PLAINS THURSDAY/FRIDAY.
THE PERSISTENT HIGH AMPLITUDE RIDGING TO THE WEST WILL CONTINUE TO
BE BOMBARDED BY SHORTWAVE TROUGHS DIVING DOWN OUT OF WESTERN
CANADA. THIS WILL FORCE THE RIDGE TO TRANSLATE EASTWARD OVER THE
CENTRAL STATES. THIS WILL IN TURN ALLOW NORTH DAKOTA TO BE
INFLUENCED BY SOUTHWESTERLY FLOW AND LEE CYCLOGENESIS. BOTH THE
12 UTC ECMWF AND THE 12 UTC GFS BOTH HAVE A SHORTWAVE TROUGH
DRAPED ACROSS THE NORTHERN PLAINS AND SURFACE LOW OVER
NORTHWESTERN SOUTH DAKOTA EARLY FRIDAY MORNING. THIS WILL ALLOW
FOR MOIST SOUTHERLY FLOW AHEAD OF THE COLD FRONT. WITH INCREASING
MOISTURE...SURFACE LOW PRESSURE...AND UPPER LEVEL DIFFLUENCE
WIDESPREAD THUNDERSTORM DEVELOPMENT IS POSSIBLE FRIDAY AFTERNOON
AND EVENING. IN ADDITION TO THOSE INGREDIENTS THE 12 UTC ECMWF IS
FORECASTING 50+ KNOTS OF 0-6 KM SHEAR...2000+ MUCAPE...AND DEW
POINTS IN THE MID TO UPPER 60S. IF THIS VERIFIES...SEVERE WEATHER
IS POSSIBLE FRIDAY AFTERNOON AND EVENING.
OTHERWISE...THE EXTENDED PERIOD LOOKS ACTIVE WITH CHANCES FOR
PRECIP THROUGHOUT THE PERIOD AS SHORTWAVES RIDE ALONG THE
NORTHERN PERIPHERY OF THE RIDGE TO OUR SOUTH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1254 AM CDT TUE JUL 9 2013
EXPECT THUNDERSTORMS AT KMOT/KBIS/KJMS TO CONTINUE THROUGH AROUND
09Z...WITH A POSSIBLE LINE GOING THROUGH KJMS AGAIN AFTER 09Z.
KDIK MAY HAVE TSTMS LINGER THROUGH 07Z...BUT KISN SHOULD BE OUT OF
THE MAIN LARGE AREA OF CONVECTION. MODELS HINTING AT MVFR CIGS
DEVELOPING BY 09Z...THEN VFR BY 12Z/15Z. CIGS SCATTERING FROM WEST
TO EAST AFT 18Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JV
SHORT TERM...RPK
LONG TERM...AJ
AVIATION...JV
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1151 PM CDT MON JUL 8 2013
.UPDATE...
ISSUED AT 1150 PM CDT MON JUL 8 2013
WILL LEAVE SEVERE T-STORM WATCH 403 AS IS FOR NOW. WILL EXTEND SVR
WATCH 402 FOR MORTON...GRANT...AND SIOUX COUNTIES FOR ONE MORE
HOUR WITH A LINE OF STORMS MOVING ACROSS THOSE COUNTIES RIGHT NOW.
WHILE THE THREAT APPEARS LOW WITH THE BETTER SEVERE PARAMETERS IN
SOUTH DAKOTA...FIGURE ONE MORE HOUR WILL NOT HURT...WHEN PERHAPS
PART OF 403 CAN BE LET GO AS WELL.
UPDATED PRODUCTS OUT SHORTLY.
UPDATE ISSUED AT 1013 PM CDT MON JUL 8 2013
UPDATED THE FORECAST TO EXTEND THE SEVERE THUNDERSTORM WATCH EAST
INTO THE JAMES RIVER VALLEY.
MCS OVER WEST CENTRAL NORTH DAKOTA DEVELOPED INTO AN MCV IN THE
LAST HOUR OR TWO. THE LEADING EDGE OF THIS ACTIVITY HAS BEEN
PRODUCING WIDESPREAD WIND GUSTS UP TO 60 MPH. THIS ACTIVITY WILL
CONTINUE TO PUSH EAST INTO THE JAMES RIVER VALLEY AFTER MIDNIGHT.
ANOTHER BOW ECHO IS PUSHING EAST ACROSS SOUTHWESTERN NORTH DAKOTA.
ITS STORM MOTION HAS BEEN EAST-SOUTHEAST AND WILL LIKELY CONTINUE
TO PUSH INTO SOUTH DAKOTA DURING THE NEXT FEW HOURS.
THE UPDATED PRODUCTS HAVE BEEN SENT.
UPDATE ISSUED AT 703 PM CDT MON JUL 8 2013
UPDATED THE FORECAST TO ADD SEVERE THUNDERSTORM WATCH 402 FOR
AREAS WEST OF HIGHWAY 83.
ONGOING CONVECTION OVER EAST-CENTRAL MONTANA SHOULD CONTINUE TO
MOVE EAST-SOUTHEAST INTO SOUTHWESTERN NORTH DAKOTA EARLY THIS
EVENING. THIS ACTIVITY IS CONGEALING INTO AN MCS AND IS MOVING
INTO A FAVORABLE ENVIRONMENT FOR MCS MAINTENANCE (SURFACE BASED
CAPE AROUND 2000 J/KG PER LATEST LAPS ANALYSIS). THIS INITIAL
CONVECTIVE ACTIVITY PROMPTED SPC TO ISSUE A SEVERE THUNDERSTORM
WATCH FOR AREAS WEST OF HIGHWAY 83 UNTIL MIDNIGHT CDT.
SHORT-RANGE MESOSCALE MODELS CONTINUE TO PROG THE PRIMARY LINE
OF CONVECTION (CURRENTLY EXTENDING FROM GLASGOW TO BILLINGS) TO
PUSH INTO WESTERN NORTH DAKOTA AROUND 03Z...AND SWEEP ACROSS THE
CWA TONIGHT. THE FLY IN THE OINTMENT IS JUST HOW MUCH INSTABILITY
THE INITIAL MCS CHEWS UP BEFORE THE PRIMARY LINE SWINGS THROUGH.
STILL WILL MAINTAIN SEVERE WORDING PAST MIDNIGHT FOR CENTRAL NORTH
DAKOTA. HOWEVER...WILL CONTINUE TO MONITOR EVENING TRENDS AND
MAKE ANY ADJUSTMENTS AS NEEDED. THE UPDATED GRIDDED AND TEXT
PRODUCTS HAVE BEEN SENT.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 341 PM CDT MON JUL 8 2013
THE MAIN FORECAST ISSUE DURING THE SHORT TERM IS STORM
COVERAGE/TIMING/SEVERITY THROUGH TONIGHT. SCATTERED STORMS ARE
EXPECTED TO DEVELOP AND/OR MOVE INTO THE WEST LATE THIS AFTERNOON.
MORE FAVORABLE DEEP LAYER SHEAR IS CONFINED TO THE WEST THROUGH
LATE AFTERNOON. SOME ISOLATED SEVERE STORMS ARE POSSIBLE...WITH
LARGE HAIL THE MAIN THREAT. THE HRRR IS STILL FOCUSING ON THE SOUTHWEST
FOR INITIATION...WHILE THE 12Z WRF FOCUSES ON A FRONT STRETCHING
FROM WEST CENTRAL INTO NORTH CENTRAL NORTH DAKOTA. WILL CONTINUE
TO MONITOR CLOSELY FOR INITIATION. AN INTENSE SUPERCELL IS MOVING
THROUGH NORTHEAST MONTANA...AND WOULD IMPACT THE FORECAST AREA
AFTER 00Z IF IT HOLDS TOGETHER. A BIGGER CONCERN WILL BE A
THUNDERSTORM COMPLEX THAT WILL LIKELY TRACK FROM WEST TO EAST
ACROSS THE FORECAST AREA AFTER AROUND 9 PM CDT. DAMAGING STRAIGHT
LINE WINDS WILL BE THE BIGGEST THREAT. FAST STORM MOTIONS SHOULD
PRECLUDE WIDESPREAD FLASH FLOODING. A MULTI- MEDIA WEATHER BRIEFING
HAS BEEN POSTED AT WWW.WEATHER.GOV/BIS. THE SEVERE THREAT MAY
PERSIST AFTER MIDNIGHT TONIGHT BEFORE STORMS WEAKEN. ADDITIONAL
NON-SEVERE STORMS WILL BE LIKELY THROUGH AT LEAST MIDDAY TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 341 PM CDT MON JUL 8 2013
MAIN HIGHLIGHT FOR THE LONG TERM IS SHORTWAVE TROUGH AND
ASSOCIATED COLD FRONT ENTERING NORTHERN PLAINS THURSDAY/FRIDAY.
THE PERSISTENT HIGH AMPLITUDE RIDGING TO THE WEST WILL CONTINUE TO
BE BOMBARDED BY SHORTWAVE TROUGHS DIVING DOWN OUT OF WESTERN
CANADA. THIS WILL FORCE THE RIDGE TO TRANSLATE EASTWARD OVER THE
CENTRAL STATES. THIS WILL IN TURN ALLOW NORTH DAKOTA TO BE
INFLUENCED BY SOUTHWESTERLY FLOW AND LEE CYCLOGENESIS. BOTH THE
12 UTC ECMWF AND THE 12 UTC GFS BOTH HAVE A SHORTWAVE TROUGH
DRAPED ACROSS THE NORTHERN PLAINS AND SURFACE LOW OVER
NORTHWESTERN SOUTH DAKOTA EARLY FRIDAY MORNING. THIS WILL ALLOW
FOR MOIST SOUTHERLY FLOW AHEAD OF THE COLD FRONT. WITH INCREASING
MOISTURE...SURFACE LOW PRESSURE...AND UPPER LEVEL DIFFLUENCE
WIDESPREAD THUNDERSTORM DEVELOPMENT IS POSSIBLE FRIDAY AFTERNOON
AND EVENING. IN ADDITION TO THOSE INGREDIENTS THE 12 UTC ECMWF IS
FORECASTING 50+ KNOTS OF 0-6 KM SHEAR...2000+ MUCAPE...AND DEW
POINTS IN THE MID TO UPPER 60S. IF THIS VERIFIES...SEVERE WEATHER
IS POSSIBLE FRIDAY AFTERNOON AND EVENING.
OTHERWISE...THE EXTENDED PERIOD LOOKS ACTIVE WITH CHANCES FOR
PRECIP THROUGHOUT THE PERIOD AS SHORTWAVES RIDE ALONG THE
NORTHERN PERIPHERY OF THE RIDGE TO OUR SOUTH.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 703 PM CDT MON JUL 8 2013
THE MAIN FOCUS THROUGH THE TAF PERIOD IS THUNDERSTORMS.
OTHERWISE...EXPECT VFR CONDITIONS. SCATTERED STORMS ARE EXPECTED
THIS EVENING...BUT TOUGH TO PINPOINT FAVORED AREA FOR DEVELOPMENT
AND TIMING. LATER TONIGHT...AFTER 02Z...ENHANCED WINDS WILL BE
POSSIBLE WITH FAST MOVING LINES OF THUNDERSTORMS. ALTHOUGH THESE
SEVERE WEATHER ELEMENTS WILL BE POSSIBLE..TOO UNCERTAIN IN TIMING
TO INCLUDE IN TAF FORECAST. AVIATION PLANNERS SHOULD ANTICIPATE
MULTIPLE LINES OF THUNDERSTORMS MOVING WEST TO EAST ACROSS THE
STATE AFTER 02Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...RPK
LONG TERM...AJ
AVIATION...TM
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
832 PM EDT WED JUL 10 2013
.SYNOPSIS...
A STRONG COLD FRONT OVER LAKE ERIE WILL MOVE SOUTHEAST ACROSS THE
AREA EARLY TONIGHT. HIGH PRESSURE WILL BUILD OVER THE REGION FROM
THE NORTHWEST THURSDAY AND FRIDAY THEN MOVE TO THE EAST COAST
SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
THE STRONG CONVECTION HAS MOVED SE OF THE CWA SO THE SVR TSTM
WATCH HAS BEEN ALLOWED TO EXPIRE AND THE FLOOD WATCH ALSO HAS
EXPIRED FOR ALL BUT NW PA WHERE A FEW LINGERING CONVECTIVE CELLS
MAY CONTINUE TO AFFECT THE AREA THE NEXT FEW HOURS.
THE HRRR CONTINUES TO SHOW NUMEROUS CONVECTIVE CELLS DEVELOPING
FROM LERI INTO NRN OH AND NW PA THRU MIDNIGHT BUT HAS BACKED DOWN
SINCE THE PREVIOUS RUN. WILL SOMEWHAT USE THE GENERAL THEME OF THE
HRRR BUT SINCE IT IS CURRENTLY FAIRLY WRONG WON`T GO AS HIGH ON
THE POPS...QPF ETC.
LOWER DEWPOINTS FINALLY STARTING TO PUSH INTO TOL AREA GIVING HOPE
THAT THE END IS NEAR FOR THE MISERY OF THE PAST FEW WEEKS.
MANY AREAS ARE IN FLOOD AND WILL TAKE QUITE A WHILE FOR WATERS TO
RECEDE.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY NIGHT/...
HIGH PRESSURE WILL DOMINATE THE PERIOD. THE DAYTIME HOURS SHOULD
BE MAINLY PARTLY CLOUDY WITH CLEAR SKIES AT NIGHT. FRIDAY MORNING
WILL BE COOL WITH TEMPS IN THE MIDDLE 50S. BY THE WEEKEND TEMPS
WILL START TO WARM AS THE SURFACE RIDGE MOVES OFF TO THE EAST.
HAVE USED A BLEND OF TEMPS TODAY GIVEN LACK OF TIME.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
A GENERALLY DRIER PATTERN WITH ABOVE NORMAL TEMPERATURES.
HIGH PRESSURE WILL BE IN CONTROL FOR SUNDAY AND EARLY IN THE WEEK.
THE MODELS ARE TRYING TO HINT AT A THREAT OF SOME SHOWERS AND
THUNDERSTORMS WEDNESDAY AS A WEAK SURFACE TROF TRIES TO MOVE THROUGH
THE RIDGE. ON THE EDGE ABOUT THIS WITH SO MUCH HIGH PRESSURE IN THE
AREA. ABOVE NORMAL TEMPERATURES.
&&
.AVIATION /01Z THURSDAY THROUGH MONDAY/...
THE COLD FRONT OVER NW OHIO WILL CROSS NE OH/NW PA EARLY TONIGHT.
A SHOWER/STORM COULD OCCUR AT KERI EARLY TONIGHT OTHERWISE
CLEARING WILL PROCEED AND EVERYONE SHOULD BE VFR. SHOULD BE ENOUGH
OF A BREEZE TO KEEP FOG FROM FORMING. MVFR CUMULUS WILL DEVELOP
THUR MORNING AND LIFT TO VFR EARLY IN THE AFTERNOON...THEN CLEAR
BY EVENING. THE NORTH WIND WILL BE A LITTLE GUSTY ON THURSDAY.
.OUTLOOK...VFR.
&&
.MARINE...
SMALL CRAFT ADVISORY IN EFFECT ON THE EAST END OF THE LAKE BECAUSE
OF THE HIGH WAVES BECAUSE OF THE SOUTHWEST FLOW. THE WINDS AND WAVES
SHOULD DECREASE EARLY THIS EVENING AFTER THE FRONTAL PASSAGE. THE
FLOW WILL BE NORTH OR NORTHWEST AND SHOULD BE LIGHT ENOUGH NOT TO
NEED A SMALL CRAFT ADVISORY. THIS WILL HAVE TO BE WATCHED.
OTHERWISE FOR THE REST OF THE WEEK AND THE WEEKEND AND INTO EARLY
NEXT WEEK...HIGH PRESSURE WILL BE BUILDING INTO THE AREA. THE FLOW
EVENTUALLY WILL BECOME SOUTHWEST ON THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...FLASH FLOOD WATCH UNTIL 10 PM EDT THIS EVENING FOR PAZ001>003.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR LEZ148-
149.
&&
$$
SYNOPSIS...KUBINA
NEAR TERM...ADAMS/KUBINA
SHORT TERM...KUBINA
LONG TERM...KIELTYKA
AVIATION...KOSARIK
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1033 AM EDT TUE JUL 9 2013
.SYNOPSIS...
THE WEATHER WILL REMAIN UNSETTLED ACROSS THE LOWER GREAT LAKES AND
OHIO VALLEY TODAY AND TONIGHT AHEAD OF A COLD FRONT THAT WILL MOVE
THROUGH THE AREA ON WEDNESDAY. THURSDAY AND FRIDAY HIGH PRESSURE
AND DRY STABLE AIR WILL BUILD IN.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NUMEROUS FLOOD WARNINGS REMAIN IN EFFECT FROM 2-4 INCHES OF HEAVY
RAIN THAT FELL OVERNIGHT. FORTUNATELY DRIER AIR ALOFT IS
OVERSPREADING THE AREA AS SEEN ON THE 12Z DTX SOUNDING WITH LARGER
SCALE SUBSIDENCE IN THE WAKE OF LAST NIGHTS SHORTWAVE. EXPECT
SEVERAL HOURS OF DRY CONDITIONS THROUGH MID AFTERNOON WITH
INSTABILITY STARTING TO CREEP BACK UP FROM THE SOUTH LATE IN THE
DAY AS DEWPOINTS REMAIN IN THE LOW 70S. WE COULD START TO SEE SOME
SCATTERED SHOWERS AND THUNDERSTORMS DEVELOP IN OUR SOUTHWESTERN
COUNTIES THAT RECEIVED THE HEAVY RAIN OVERNIGHT BY LATE AFTERNOON.
WE ARE ALSO KEEPING AN EYE ON THE CONVECTION MOVING INTO WESTERN
ILLINOIS AS IT APPROACHES LATER TODAY FOR BOUNDARIES THAT MAY HELP KICK
OFF SHOWERS AND THUNDERSTORMS ALONG THE STALLED WARM FRONTAL
BOUNDARY ACROSS INDIANA/WESTERN OHIO. OTHERWISE ANOTHER ROUND OF RAIN
IS STILL EXPECTED OVERNIGHT INTO TOMORROW AND THE THREAT FOR
FLOODING CONTINUES.
ORIGINAL...FOR THE MORNING EXPECT THE TREND IN PLACE TO SLOWLY
CONTINUE WITH PRECIP MOVING EAST/SOUTHEAST OF THE AREA AND DRIER
AIR MOVING IN FROM THE NORTHWEST. SHOULD EVENTUALLY SEE SOME SS
TODAY HOWEVER HRRR DOES SHOW SCATTERED CONVECTION REDEVELOPING IN
THE MOIST UNSTABLE AIR STILL IN PLACE ACROSS THE AREA LATER THIS
AFTERNOON. BEST CHANCES WOULD BE WEST/SWRN COUNTIES. WILL BRING
CHANCE POPS BACK TO THE SRN/SWRN COUNTIES WITH SLIGHT CHANCE POPS
ON THE NORTH SIDE OF THAT. HIGHS NEAR GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
FOLLOWED MIX OF HPC/NAM AND SREF GUIDANCE FOR THE SHORT TERM. COLD
FRONT IS ON THE WAY FOR WEDNESDAY AND TONIGHT AHEAD OF THE FRONT MODELS
SHOWED A COUPLE SHORT WAVES MOVING ACROSS THE REGION. EXPECTING
SHOWERS/THUNDERSTORMS MOVING IN FROM THE WEST LATE EVENING OR
EARLY IN THE NIGHT AND PERSISTING THROUGH MUCH OF WEDNESDAY. WOULD
ANTICIPATE THE NEED FOR A FLOOD WATCH BUT GIVEN THE CURRENT
HEADLINE WILL WAIT FOR DAY SHIFT TO REEVALUATE. GIVEN HPC QPF
VALUES INCREASED MAV GUIDANCE POPS AGREEING MORE WITH THE SREF
CATEGORICAL GUIDANCE TONIGHT AND WEDNESDAY. THURSDAY AND FRIDAY
SUN AND DRY.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
MODELS HAVE BEEN SLOWLY TRENDING TO A DRIER WEEKEND WITH THE CENTRAL
U.S. RIDGE TRYING TO NOSE INTO THE LOWER GREAT LAKES AND THE TROUGH
SHIFTING TO THE EAST COAST. THIS WILL PUT IS IN THE MIDDLE AND WILL
KEEP THE DRY WEEKEND FORECAST AND THE LOW PRECIP CHANCES FOR MONDAY
WITH AN INCREASE IN MOISTURE. WILL PUT TEMPS IN BETWEEN GFS AND
ECMWF GUIDANCE AS A COMPROMISE SEEMS BEST RIGHT NOW. THAT WILL GIVE
US SEASONABLE TEMPS FOR THE WEEKEND IN THE LOWER TO MID 80S.
&&
.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
RELATIVE LULL TODAY IN SHOWERS/TS ALTHOUGH A FEW MIGHT START TO
POP UP AGAIN LATE THIS AFTERNOON FOR FDY/MFD/CAK. SOME MORNING BR
TO START ALONG WITH SOME MVFR CIGS. EXPECTING IMPROVEMENT TO VFR
FOR MIDDAY AND INTO THE AFTERNOON. WINDS WILL SHIFT TO THE WEST
TODAY AND BRING IN SOMEWHAT DRIER AIR. TONIGHT THOUGH SHOWERS/TS
TO BREAK OUT ONCE AGAIN AS FLOW COMES BACK AROUND TO THE SSW. A
COLD FRONT WILL APPROACH FOR WEDNESDAY SO MORE WIDESPREAD SHRA/TS
TOWARD DAWN AND BEYOND. SOME OF THOSE COULD BE STRONG TO SEVERE.
HEAVY RAIN AND IFR CONDITIONS WITHIN TS.
.OUTLOOK...NON-VFR EXPECTED IN SHOWERS AND THUNDERSTORMS THROUGH
WEDNESDAY NIGHT.
&&
.MARINE...
A RELATIVE LULL IN THE THUNDERSTORM CHANCES FOR TODAY. SOUTH-SW FLOW
WILL CONTINUE WITH A NEARLY STATIONARY BOUNDARY JUST NORTH OF THE
LAKE. LOW PRESSURE WILL TRACK ACROSS THE NORTHERN LAKES WEDNESDAY
AND TAKE A COLD FRONT ACROSS LAKE ERIE WITH ANOTHER ROUND OF
THUNDERSTORMS...SOME OF WHICH WILL BE ON THE STRONG SIDE. WINDS MAY
PICK UP ENOUGH TO NEED A SMALL CRAFT ADV WITH THIS SYSTEM. SOME CHOP
POSSIBLE WEDNESDAY AHEAD OF THE FRONT FOR THE EASTERN NEARSHORE WITH
SW FLOW ALONG THE LENGTH OF THE LAKE. BETTER CHANCES FOR SMALL CRAFT
ADV CONDITIONS IN THE NORTHWEST FLOW AFTER THE FRONT. THE WEATHER
SETTLES DOWN THURSDAY THROUGH SATURDAY WITH HIGH PRESSURE OVER THE
CENTRAL GREAT LAKES. WILL HAVE A NORTHERLY FLOW THAT WILL BECOME ENE
BY SATURDAY AS THE HIGH SHIFTS EAST...REMAINING NORTH OF LAKE ERIE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TK
NEAR TERM...KEC/TK
SHORT TERM...TK/KOSARIK
LONG TERM...OUDEMAN
AVIATION...OUDEMAN
MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
751 AM EDT TUE JUL 9 2013
.SYNOPSIS...
THE WEATHER WILL REMAIN UNSETTLED ACROSS THE LOWER GREAT LAKES AND
OHIO VALLEY TODAY AND TONIGHT AHEAD OF A COLD FRONT THAT WILL MOVE
THROUGH THE AREA ON WEDNESDAY. THURSDAY AND FRIDAY HIGH PRESSURE
AND DRY STABLE AIR WILL BUILD IN.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...CANCELLED THE FLASH FLOOD WATCH. ALTHOUGH FLOODING IS
ONGOING...WILL HANDLY WITH CURRENT WARNINGS. THREAT OF ADDITIONAL
FLOOD PRODUCING RAIN HAS DIMINISHED FOOR TODAY.
ORIGINAL...MADE ADJUSTMENT TO THE FLOOD WATCH TRIMMING THE
NORTHERN COUNTIES BUT EXTENDING IT A FEW HOURS INTO THE MORNING
FOR THE REMAINING SOUTHERN COUNTIES. RADAR SHOWS THE HEAVY RAIN
MOVING SLOWLY EAST HOWEVER MORE SHOWERS HAVE DEVELOPED ON THE WEST
SIDE OF THE MAIN CONVECTION ACROSS PORTIONS OF CRAWFORD/WYANDOT
AND MARION COUNTIES. RAIN STILL OCCURRING ACROSS THE CENTRAL
LAKESHORE BUT IS NOT INTENSE ENOUGH TO CAUSE FLOODING. FOR THE
MORNING EXPECT THE TREND IN PLACE TO SLOWLY CONTINUE WITH PRECIP
MOVING EAST/SOUTHEAST OF THE AREA AND DRIER AIR MOVING IN FROM THE
NORTHWEST. SHOULD EVENTUALLY SEE SOME SS TODAY HOWEVER HRRR DOES
SHOW SCATTERED CONVECTION REDEVELOPING IN THE MOIST UNSTABLE AIR
STILL IN PLACE ACROSS THE AREA LATER THIS AFTERNOON. BEST CHANCES
WOULD BE WEST/SWRN COUNTIES. WILL BRING CHANCE POPS BACK TO THE
SRN/SWRN COUNTIES WITH SLIGHT CHANCE POPS ON THE NORTH SIDE OF
THAT. HIGHS NEAR GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
FOLLOWED MIX OF HPC/NAM AND SREF GUIDANCE FOR THE SHORT TERM. COLD
FRONT IS ON THE WAY FOR WEDNESDAY AND TONIGHT AHEAD OF THE FRONT MODELS
SHOWED A COUPLE SHORT WAVES MOVING ACROSS THE REGION. EXPECTING
SHOWERS/THUNDERSTORMS MOVING IN FROM THE WEST LATE EVENING OR
EARLY IN THE NIGHT AND PERSISTING THROUGH MUCH OF WEDNESDAY. WOULD
ANTICIPATE THE NEED FOR A FLOOD WATCH BUT GIVEN THE CURRENT
HEADLINE WILL WAIT FOR DAY SHIFT TO REEVALUATE. GIVEN HPC QPF
VALUES INCREASED MAV GUIDANCE POPS AGREEING MORE WITH THE SREF
CATEGORICAL GUIDANCE TONIGHT AND WEDNESDAY. THURSDAY AND FRIDAY
SUN AND DRY.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
MODELS HAVE BEEN SLOWLY TRENDING TO A DRIER WEEKEND WITH THE CENTRAL
U.S. RIDGE TRYING TO NOSE INTO THE LOWER GREAT LAKES AND THE TROUGH
SHIFTING TO THE EAST COAST. THIS WILL PUT IS IN THE MIDDLE AND WILL
KEEP THE DRY WEEKEND FORECAST AND THE LOW PRECIP CHANCES FOR MONDAY
WITH AN INCREASE IN MOISTURE. WILL PUT TEMPS IN BETWEEN GFS AND
ECMWF GUIDANCE AS A COMPROMISE SEEMS BEST RIGHT NOW. THAT WILL GIVE
US SEASONABLE TEMPS FOR THE WEEKEND IN THE LOWER TO MID 80S.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
RELATIVE LULL TODAY IN SHOWERS/TS ALTHOUGH A FEW MIGHT START TO
POP UP AGAIN LATE THIS AFTERNOON FOR FDY/MFD/CAK. SOME MORNING BR
TO START ALONG WITH SOME MVFR CIGS. EXPECTING IMPROVEMENT TO VFR
FOR MIDDAY AND INTO THE AFTERNOON. WINDS WILL SHIFT TO THE WEST
TODAY AND BRING IN SOMEWHAT DRIER AIR. TONIGHT THOUGH SHOWERS/TS
TO BREAK OUT ONCE AGAIN AS FLOW COMES BACK AROUND TO THE SSW. A
COLD FRONT WILL APPROACH FOR WEDNESDAY SO MORE WIDESPREAD SHRA/TS
TOWARD DAWN AND BEYOND. SOME OF THOSE COULD BE STRONG TO SEVERE.
HEAVY RAIN AND IFR CONDITIONS WITHIN TS.
.OUTLOOK...NON-VFR EXPECTED IN SHOWERS AND THUNDERSTORMS THROUGH
WEDNESDAY NIGHT.
&&
.MARINE...
A RELATIVE LULL IN THE THUNDERSTORM CHANCES FOR TODAY. SOUTH-SW FLOW
WILL CONTINUE WITH A NEARLY STATIONARY BOUNDARY JUST NORTH OF THE
LAKE. LOW PRESSURE WILL TRACK ACROSS THE NORTHERN LAKES WEDNESDAY
AND TAKE A COLD FRONT ACROSS LAKE ERIE WITH ANOTHER ROUND OF
THUNDERSTORMS...SOME OF WHICH WILL BE ON THE STRONG SIDE. WINDS MAY
PICK UP ENOUGH TO NEED A SMALL CRAFT ADV WITH THIS SYSTEM. SOME CHOP
POSSIBLE WEDNESDAY AHEAD OF THE FRONT FOR THE EASTERN NEARSHORE WITH
SW FLOW ALONG THE LENGTH OF THE LAKE. BETTER CHANCES FOR SMALL CRAFT
ADV CONDITIONS IN THE NORTHWEST FLOW AFTER THE FRONT. THE WEATHER
SETTLES DOWN THURSDAY THROUGH SATURDAY WITH HIGH PRESSURE OVER THE
CENTRAL GREAT LAKES. WILL HAVE A NORTHERLY FLOW THAT WILL BECOME ENE
BY SATURDAY AS THE HIGH SHIFTS EAST...REMAINING NORTH OF LAKE ERIE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TK
NEAR TERM...TK
SHORT TERM...TK/KOSARIK
LONG TERM...OUDEMAN
AVIATION...OUDEMAN
MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
741 AM EDT TUE JUL 9 2013
.SYNOPSIS...
THE WEATHER WILL REMAIN UNSETTLED ACROSS THE LOWER GREAT LAKES AND
OHIO VALLEY TODAY AND TONIGHT AHEAD OF A COLD FRONT THAT WILL MOVE
THROUGH THE AREA ON WEDNESDAY. THURSDAY AND FRIDAY HIGH PRESSURE
AND DRY STABLE AIR WILL BUILD IN.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...MADE ADJUSTMENT TO SKY GRIDS TODAY THROUGH THE NEXT
COUPLE DAYS. ALSO ADJUSTED POPS AND WX BASED ON CURRENT RADAR.
ORIGINAL...MADE ADJUSTMENT TO THE FLOOD WATCH TRIMMING THE
NORTHERN COUNTIES BUT EXTENDING IT A FEW HOURS INTO THE MORNING
FOR THE REMAINING SOUTHERN COUNTIES. RADAR SHOWS THE HEAVY RAIN
MOVING SLOWLY EAST HOWEVER MORE SHOWERS HAVE DEVELOPED ON THE WEST
SIDE OF THE MAIN CONVECTION ACROSS PORTIONS OF CRAWFORD/WYANDOT
AND MARION COUNTIES. RAIN STILL OCCURRING ACROSS THE CENTRAL
LAKESHORE BUT IS NOT INTENSE ENOUGH TO CAUSE FLOODING. FOR THE
MORNING EXPECT THE TREND IN PLACE TO SLOWLY CONTINUE WITH PRECIP
MOVING EAST/SOUTHEAST OF THE AREA AND DRIER AIR MOVING IN FROM THE
NORTHWEST. SHOULD EVENTUALLY SEE SOME SS TODAY HOWEVER HRRR DOES
SHOW SCATTERED CONVECTION REDEVELOPING IN THE MOIST UNSTABLE AIR
STILL IN PLACE ACROSS THE AREA LATER THIS AFTERNOON. BEST CHANCES
WOULD BE WEST/SWRN COUNTIES. WILL BRING CHANCE POPS BACK TO THE
SRN/SWRN COUNTIES WITH SLIGHT CHANCE POPS ON THE NORTH SIDE OF
THAT. HIGHS NEAR GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
FOLLOWED MIX OF HPC/NAM AND SREF GUIDANCE FOR THE SHORT TERM. COLD
FRONT IS ON THE WAY FOR WEDNESDAY AND TONIGHT AHEAD OF THE FRONT MODELS
SHOWED A COUPLE SHORT WAVES MOVING ACROSS THE REGION. EXPECTING
SHOWERS/THUNDERSTORMS MOVING IN FROM THE WEST LATE EVENING OR
EARLY IN THE NIGHT AND PERSISTING THROUGH MUCH OF WEDNESDAY. WOULD
ANTICIPATE THE NEED FOR A FLOOD WATCH BUT GIVEN THE CURRENT
HEADLINE WILL WAIT FOR DAY SHIFT TO REEVALUATE. GIVEN HPC QPF
VALUES INCREASED MAV GUIDANCE POPS AGREEING MORE WITH THE SREF
CATEGORICAL GUIDANCE TONIGHT AND WEDNESDAY. THURSDAY AND FRIDAY
SUN AND DRY.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
MODELS HAVE BEEN SLOWLY TRENDING TO A DRIER WEEKEND WITH THE CENTRAL
U.S. RIDGE TRYING TO NOSE INTO THE LOWER GREAT LAKES AND THE TROUGH
SHIFTING TO THE EAST COAST. THIS WILL PUT IS IN THE MIDDLE AND WILL
KEEP THE DRY WEEKEND FORECAST AND THE LOW PRECIP CHANCES FOR MONDAY
WITH AN INCREASE IN MOISTURE. WILL PUT TEMPS IN BETWEEN GFS AND
ECMWF GUIDANCE AS A COMPROMISE SEEMS BEST RIGHT NOW. THAT WILL GIVE
US SEASONABLE TEMPS FOR THE WEEKEND IN THE LOWER TO MID 80S.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
RELATIVE LULL TODAY IN SHOWERS/TS ALTHOUGH A FEW MIGHT START TO
POP UP AGAIN LATE THIS AFTERNOON FOR FDY/MFD/CAK. SOME MORNING BR
TO START ALONG WITH SOME MVFR CIGS. EXPECTING IMPROVEMENT TO VFR
FOR MIDDAY AND INTO THE AFTERNOON. WINDS WILL SHIFT TO THE WEST
TODAY AND BRING IN SOMEWHAT DRIER AIR. TONIGHT THOUGH SHOWERS/TS
TO BREAK OUT ONCE AGAIN AS FLOW COMES BACK AROUND TO THE SSW. A
COLD FRONT WILL APPROACH FOR WEDNESDAY SO MORE WIDESPREAD SHRA/TS
TOWARD DAWN AND BEYOND. SOME OF THOSE COULD BE STRONG TO SEVERE.
HEAVY RAIN AND IFR CONDITIONS WITHIN TS.
.OUTLOOK...NON-VFR EXPECTED IN SHOWERS AND THUNDERSTORMS THROUGH
WEDNESDAY NIGHT.
&&
.MARINE...
A RELATIVE LULL IN THE THUNDERSTORM CHANCES FOR TODAY. SOUTH-SW FLOW
WILL CONTINUE WITH A NEARLY STATIONARY BOUNDARY JUST NORTH OF THE
LAKE. LOW PRESSURE WILL TRACK ACROSS THE NORTHERN LAKES WEDNESDAY
AND TAKE A COLD FRONT ACROSS LAKE ERIE WITH ANOTHER ROUND OF
THUNDERSTORMS...SOME OF WHICH WILL BE ON THE STRONG SIDE. WINDS MAY
PICK UP ENOUGH TO NEED A SMALL CRAFT ADV WITH THIS SYSTEM. SOME CHOP
POSSIBLE WEDNESDAY AHEAD OF THE FRONT FOR THE EASTERN NEARSHORE WITH
SW FLOW ALONG THE LENGTH OF THE LAKE. BETTER CHANCES FOR SMALL CRAFT
ADV CONDITIONS IN THE NORTHWEST FLOW AFTER THE FRONT. THE WEATHER
SETTLES DOWN THURSDAY THROUGH SATURDAY WITH HIGH PRESSURE OVER THE
CENTRAL GREAT LAKES. WILL HAVE A NORTHERLY FLOW THAT WILL BECOME ENE
BY SATURDAY AS THE HIGH SHIFTS EAST...REMAINING NORTH OF LAKE ERIE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...FLASH FLOOD WATCH UNTIL 9 AM EDT THIS MORNING FOR OHZ027>030-
036-037-047.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TK
NEAR TERM...TK
SHORT TERM...TK/KOSARIK
LONG TERM...OUDEMAN
AVIATION...OUDEMAN
MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
646 AM EDT TUE JUL 9 2013
.SYNOPSIS...
THE WEATHER WILL REMAIN UNSETTLED ACROSS THE LOWER GREAT LAKES AND
OHIO VALLEY TODAY AND TONIGHT AHEAD OF A COLD FRONT THAT WILL MOVE
THROUGH THE AREA ON WEDNESDAY. THURSDAY AND FRIDAY HIGH PRESSURE
AND DRY STABLE AIR WILL BUILD IN.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...MADE ADJUSTMENT TO SKY GRIDS TODAY THROUGH THE NEXT
COUPLE DAYS. ALSO ADJUSTED POPS AND WX BASED ON CURRENT RADAR.
ORIGINAL...MADE ADJUSTMENT TO THE FLOOD WATCH TRIMMING THE
NORTHERN COUNTIES BUT EXTENDING IT A FEW HOURS INTO THE MORNING
FOR THE REMAINING SOUTHERN COUNTIES. RADAR SHOWS THE HEAVY RAIN
MOVING SLOWLY EAST HOWEVER MORE SHOWERS HAVE DEVELOPED ON THE WEST
SIDE OF THE MAIN CONVECTION ACROSS PORTIONS OF CRAWFORD/WYANDOT
AND MARION COUNTIES. RAIN STILL OCCURRING ACROSS THE CENTRAL
LAKESHORE BUT IS NOT INTENSE ENOUGH TO CAUSE FLOODING. FOR THE
MORNING EXPECT THE TREND IN PLACE TO SLOWLY CONTINUE WITH PRECIP
MOVING EAST/SOUTHEAST OF THE AREA AND DRIER AIR MOVING IN FROM THE
NORTHWEST. SHOULD EVENTUALLY SEE SOME SS TODAY HOWEVER HRRR DOES
SHOW SCATTERED CONVECTION REDEVELOPING IN THE MOIST UNSTABLE AIR
STILL IN PLACE ACROSS THE AREA LATER THIS AFTERNOON. BEST CHANCES
WOULD BE WEST/SWRN COUNTIES. WILL BRING CHANCE POPS BACK TO THE
SRN/SWRN COUNTIES WITH SLIGHT CHANCE POPS ON THE NORTH SIDE OF
THAT. HIGHS NEAR GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
FOLLOWED MIX OF HPC/NAM AND SREF GUIDANCE FOR THE SHORT TERM. COLD
FRONT IS ON THE WAY FOR WEDNESDAY AND TONIGHT AHEAD OF THE FRONT MODELS
SHOWED A COUPLE SHORT WAVES MOVING ACROSS THE REGION. EXPECTING
SHOWERS/THUNDERSTORMS MOVING IN FROM THE WEST LATE EVENING OR
EARLY IN THE NIGHT AND PERSISTING THROUGH MUCH OF WEDNESDAY. WOULD
ANTICIPATE THE NEED FOR A FLOOD WATCH BUT GIVEN THE CURRENT
HEADLINE WILL WAIT FOR DAY SHIFT TO REEVALUATE. GIVEN HPC QPF
VALUES INCREASED MAV GUIDANCE POPS AGREEING MORE WITH THE SREF
CATEGORICAL GUIDANCE TONIGHT AND WEDNESDAY. THURSDAY AND FRIDAY
SUN AND DRY.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
MODELS HAVE BEEN SLOWLY TRENDING TO A DRIER WEEKEND WITH THE CENTRAL
U.S. RIDGE TRYING TO NOSE INTO THE LOWER GREAT LAKES AND THE TROUGH
SHIFTING TO THE EAST COAST. THIS WILL PUT IS IN THE MIDDLE AND WILL
KEEP THE DRY WEEKEND FORECAST AND THE LOW PRECIP CHANCES FOR MONDAY
WITH AN INCREASE IN MOISTURE. WILL PUT TEMPS IN BETWEEN GFS AND
ECMWF GUIDANCE AS A COMPROMISE SEEMS BEST RIGHT NOW. THAT WILL GIVE
US SEASONABLE TEMPS FOR THE WEEKEND IN THE LOWER TO MID 80S.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
SCATTERED SHOWERS AND THUNDERSTORMS REMAIN FOR THE REMAINDER OF
THE NIGHT. IFR WITHIN THESE SHRA/TS. SOME AREAS OF MVFR AS WELL.
BIGGEST TASK IS WHETHER NON VFR CEILINGS OF VSBYS WILL DEVELOP IN
A MORE WIDESPREAD NATURE. LATEST SREF BRINGS IN MVFR AND SOME IFR
ACROSS SOUTHERN MI ACROSS ONTARIO AND INTO NW PA. HAVE LEANED THIS
WAY AND HAVE BROUGHT THE LOWEST CONDITIONS INTO TOLEDO. WITH
DOWNSLOPE FLOW DID NOT GO TOO LOW AT ERIE. EVEN THOUGH THERE IS
PLENTY OF LOW LEVEL MOISTURE...LIGHT WIND AND CURRENT CIGS SHOULD
PREVENT VSBY FROM GETTING TOO LOW. START MOST AT MVFR IN MID
MORNING...IMPROVING TO VFR. MOST OF THE SHOWERS LOOK TO BE OVER BY
AROUND 12Z...BUT AREA MAY GET NEW DEVELOPMENT AGAIN TOWARD YNG/CAK
LATE THIS AFTERNOON. UNSURE ABOUT FDY/MFD. AGAIN THIS IS FOCUSING
ON THE TIMES WITH THE BEST CHANCES...STILL COULD SEE A SHRA/TS AT
JUST ABOUT ANY TIME.
.OUTLOOK...NON-VFR EXPECTED IN SHOWERS AND THUNDERSTORMS THROUGH
WEDNESDAY NIGHT.
&&
.MARINE...
A RELATIVE LULL IN THE THUNDERSTORM CHANCES FOR TODAY. SOUTH-SW FLOW
WILL CONTINUE WITH A NEARLY STATIONARY BOUNDARY JUST NORTH OF THE
LAKE. LOW PRESSURE WILL TRACK ACROSS THE NORTHERN LAKES WEDNESDAY
AND TAKE A COLD FRONT ACROSS LAKE ERIE WITH ANOTHER ROUND OF
THUNDERSTORMS...SOME OF WHICH WILL BE ON THE STRONG SIDE. WINDS MAY
PICK UP ENOUGH TO NEED A SMALL CRAFT ADV WITH THIS SYSTEM. SOME CHOP
POSSIBLE WEDNESDAY AHEAD OF THE FRONT FOR THE EASTERN NEARSHORE WITH
SW FLOW ALONG THE LENGTH OF THE LAKE. BETTER CHANCES FOR SMALL CRAFT
ADV CONDITIONS IN THE NORTHWEST FLOW AFTER THE FRONT. THE WEATHER
SETTLES DOWN THURSDAY THROUGH SATURDAY WITH HIGH PRESSURE OVER THE
CENTRAL GREAT LAKES. WILL HAVE A NORTHERLY FLOW THAT WILL BECOME ENE
BY SATURDAY AS THE HIGH SHIFTS EAST...REMAINING NORTH OF LAKE ERIE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...FLASH FLOOD WATCH UNTIL 9 AM EDT THIS MORNING FOR OHZ027>030-
036-037-047.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TK
NEAR TERM...TK
SHORT TERM...TK/KOSARIK
LONG TERM...OUDEMAN
AVIATION...OUDEMAN
MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
417 AM EDT TUE JUL 9 2013
.SYNOPSIS...
THE WEATHER WILL REMAIN UNSETTLED ACROSS THE LOWER GREAT LAKES AND
OHIO VALLEY TODAY AND TONIGHT AHEAD OF A COLD FRONT THAT WILL MOVE
THROUGH THE AREA ON WEDNESDAY. THURSDAY AND FRIDAY HIGH PRESSURE
AND DRY STABLE AIR WILL BUILD IN.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MADE ADJUSTMENT TO THE FLOOD WATCH TRIMMING THE NORTHERN COUNTIES
BUT EXTENDING IT A FEW HOURS INTO THE MORNING FOR THE REMAINING
SOUTHERN COUNTIES. RADAR SHOWS THE HEAVY RAIN MOVING SLOWLY EAST
HOWEVER MORE SHOWERS HAVE DEVELOPED ON THE WEST SIDE OF THE MAIN
CONVECTION ACROSS PORTIONS OF CRAWFORD/WYANDOT AND MARION
COUNTIES. RAIN STILL OCCURRING ACROSS THE CENTRAL LAKESHORE BUT IS
NOT INTENSE ENOUGH TO CAUSE FLOODING. FOR THE MORNING EXPECT THE
TREND IN PLACE TO SLOWLY CONTINUE WITH PRECIP MOVING
EAST/SOUTHEAST OF THE AREA AND DRIER AIR MOVING IN FROM THE
NORTHWEST. SHOULD EVENTUALLY SEE SOME SS TODAY HOWEVER HRRR DOES
SHOW SCATTERED CONVECTION REDEVELOPING IN THE MOIST UNSTABLE AIR
STILL IN PLACE ACROSS THE AREA LATER THIS AFTERNOON. BEST CHANCES
WOULD BE WEST/SWRN COUNTIES. WILL BRING CHANCE POPS BACK TO THE
SRN/SWRN COUNTIES WITH SLIGHT CHANCE POPS ON THE NORTH SIDE OF
THAT. HIGHS NEAR GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
FOLLOWED MIX OF HPC/NAM AND SREF GUIDANCE FOR THE SHORT TERM. COLD
FRONT IS ON THE WAY FOR WEDNESDAY AND TONIGHT AHEAD OF THE FRONT MODELS
SHOWED A COUPLE SHORT WAVES MOVING ACROSS THE REGION. EXPECTING
SHOWERS/THUNDERSTORMS MOVING IN FROM THE WEST LATE EVENING OR
EARLY IN THE NIGHT AND PERSISTING THROUGH MUCH OF WEDNESDAY. WOULD
ANTICIPATE THE NEED FOR A FLOOD WATCH BUT GIVEN THE CURRENT
HEADLINE WILL WAIT FOR DAY SHIFT TO REEVALUATE. GIVEN HPC QPF
VALUES INCREASED MAV GUIDANCE POPS AGREEING MORE WITH THE SREF
CATEGORICAL GUIDANCE TONIGHT AND WEDNESDAY. THURSDAY AND FRIDAY
SUN AND DRY.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
MODELS HAVE BEEN SLOWLY TRENDING TO A DRIER WEEKEND WITH THE CENTRAL
U.S. RIDGE TRYING TO NOSE INTO THE LOWER GREAT LAKES AND THE TROUGH
SHIFTING TO THE EAST COAST. THIS WILL PUT IS IN THE MIDDLE AND WILL
KEEP THE DRY WEEKEND FORECAST AND THE LOW PRECIP CHANCES FOR MONDAY
WITH AN INCREASE IN MOISTURE. WILL PUT TEMPS IN BETWEEN GFS AND
ECMWF GUIDANCE AS A COMPROMISE SEEMS BEST RIGHT NOW. THAT WILL GIVE
US SEASONABLE TEMPS FOR THE WEEKEND IN THE LOWER TO MID 80S.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
SCATTERED SHOWERS AND THUNDERSTORMS REMAIN FOR THE REMAINDER OF
THE NIGHT. IFR WITHIN THESE SHRA/TS. SOME AREAS OF MVFR AS WELL.
BIGGEST TASK IS WHETHER NON VFR CEILINGS OF VSBYS WILL DEVELOP IN
A MORE WIDESPREAD NATURE. LATEST SREF BRINGS IN MVFR AND SOME IFR
ACROSS SOUTHERN MI ACROSS ONTARIO AND INTO NW PA. HAVE LEANED THIS
WAY AND HAVE BROUGHT THE LOWEST CONDITIONS INTO TOLEDO. WITH
DOWNSLOPE FLOW DID NOT GO TOO LOW AT ERIE. EVEN THOUGH THERE IS
PLENTY OF LOW LEVEL MOISTURE...LIGHT WIND AND CURRENT CIGS SHOULD
PREVENT VSBY FROM GETTING TOO LOW. START MOST AT MVFR IN MID
MORNING...IMPROVING TO VFR. MOST OF THE SHOWERS LOOK TO BE OVER BY
AROUND 12Z...BUT AREA MAY GET NEW DEVELOPMENT AGAIN TOWARD YNG/CAK
LATE THIS AFTERNOON. UNSURE ABOUT FDY/MFD. AGAIN THIS IS FOCUSING
ON THE TIMES WITH THE BEST CHANCES...STILL COULD SEE A SHRA/TS AT
JUST ABOUT ANY TIME.
.OUTLOOK...NON-VFR EXPECTED IN SHOWERS AND THUNDERSTORMS THROUGH
WEDNESDAY NIGHT.
&&
.MARINE...
A RELATIVE LULL IN THE THUNDERSTORM CHANCES FOR TODAY. SOUTH-SW FLOW
WILL CONTINUE WITH A NEARLY STATIONARY BOUNDARY JUST NORTH OF THE
LAKE. LOW PRESSURE WILL TRACK ACROSS THE NORTHERN LAKES WEDNESDAY
AND TAKE A COLD FRONT ACROSS LAKE ERIE WITH ANOTHER ROUND OF
THUNDERSTORMS...SOME OF WHICH WILL BE ON THE STRONG SIDE. WINDS MAY
PICK UP ENOUGH TO NEED A SMALL CRAFT ADV WITH THIS SYSTEM. SOME CHOP
POSSIBLE WEDNESDAY AHEAD OF THE FRONT FOR THE EASTERN NEARSHORE WITH
SW FLOW ALONG THE LENGTH OF THE LAKE. BETTER CHANCES FOR SMALL CRAFT
ADV CONDITIONS IN THE NORTHWEST FLOW AFTER THE FRONT. THE WEATHER
SETTLES DOWN THURSDAY THROUGH SATURDAY WITH HIGH PRESSURE OVER THE
CENTRAL GREAT LAKES. WILL HAVE A NORTHERLY FLOW THAT WILL BECOME ENE
BY SATURDAY AS THE HIGH SHIFTS EAST...REMAINING NORTH OF LAKE ERIE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...FLASH FLOOD WATCH UNTIL 9 AM EDT THIS MORNING FOR OHZ027>030-
036-037-047.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TK
NEAR TERM...TK
SHORT TERM...TK/KOSARIK
LONG TERM...OUDEMAN
AVIATION...OUDEMAN
MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
413 AM EDT TUE JUL 9 2013
.SYNOPSIS...
AN UNSETTLED WEATHER PATTERN WILL CONTINUE THROUGH WEDNESDAY
NIGHT. A COLD FRONT WILL CROSS THE REGION LATE WEDNESDAY NIGHT.
HIGH PRESSURE BEHIND THE FRONT WILL BRING DRIER WEATHER TO THE
AREA THAT WILL LAST INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A DISTURBANCE MOVING EAST OUT OF CENTRAL OHIO THIS MORNING WILL
TAKE WITH IT THE STRONG MOISTURE TRANSPORT AND HEAVIER SHOWERS AND
THUNDERSTORMS. IN ITS WAKE...SCATTERED SHOWERS WILL BE POSSIBLE
THROUGH THE MORNING HOURS. ANOTHER DISTURBANCE UPSTREAM OF THE
AREA WILL HELP TO TRIGGER ADDITIONAL SHOWERS AND THUNDERSTORMS THIS
AFTERNOON. A BOUNDARY ACROSS THE OHIO RIVER THIS MORNING WILL
LIFT NORTH JUST AHEAD OF THIS DISTURBANCE AND SHOULD BE THE FOCUS OF
WHERE CONVECTION INITIATES THIS AFTERNOON. THERE ARE SUBTLE
DIFFERENCES IN WHERE THIS LOCATION WILL BE. FAVORED THE ARW FOR
THE INITIAL CONVECTION DEVELOPMENT ALONG AND NORTH OF THE
INTERSTATE 70 CORRIDOR...GRADUALLY SHIFTING SOUTH AND EAST
IN FOCUS TOWARD THE EVENING. CLOUD COVER MAY PREVENT TEMPERATURES
FROM RISING INTO THE UPPER 80S THIS AFTERNOON. AS SUCH...WENT WITH
THE MIDDLE 80S FOR MOST OF OUR ZONES. WILL KEEP THE FLASH FLOOD
WATCH UP UNTIL 10 AM FOR OUR EXTREME NORTHEASTERN ZONES...NEARER
TO THE DEPARTING CONVECTION. HAVE REMOVED THOSE COUNTIES THAT HAVE
NOT SEEN MUCH IN THE WAY OF HEAVY RAIN...AND WILL LIKELY NOT SEE
MUCH MORE RAIN BEFORE THE WATCH EXPIRES. THIS
AFTERNOON...REDEVELOPING CONVECTION COULD ONCE AGAIN POSE A
FLOODING THREAT. WILL HIGHLIGHT THIS THREAT IN THE HWO FOR NOW.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
SIMILAR TO PREVIOUS NIGHTS...IN THIS VERY MOIST AIRMASS AND WITH
A PASSING DISTURBANCE IN THE AREA...CONVECTION WILL PROBABLY BE
ONGOING AS WE HEAD INTO TONIGHT`S TIME PERIOD. THE EVENING
CONVECTION IS EXPECTED TO BE SHIFTING TOWARD THE SOUTH AND EAST IN
THE NORTHWESTERLY FLOW ALOFT TO START TONIGHT. UPSTREAM...A
DEVELOPING NOCTURNAL LOW LEVEL JET IS EXPECTED TO ENHANCE
CONVECTION AFTER SUNSET. THIS CONVECTION WILL PERSIST ACROSS
PORTIONS OF OUR AREA OVERNIGHT. THERE IS UNCERTAINTY AS TO WHERE
EXACTLY THESE STORMS WILL OCCUR. THEREFORE...COULD NOT LEAN THE POPS
ONE WAY OR ANOTHER GEOGRAPHICALLY IN THE FORECAST AREA DURING THIS
PACKAGE ISSUANCE. REGARDLESS...ANY CONVECTION THAT DOES OCCUR
COULD STILL POSE A FLOOD THREAT...IN ADDITION TO ISOLATED HAIL AND
DAMAGING WINDS SHOULD STORMS BECOME INTENSE. TONIGHT`S SEVERE
PROBABILITY APPEARS LOW AT THIS TIME. THEREFORE WILL ONLY HIGHLIGHT
THE FLOODING THREAT IN THE HWO FOR THIS TIME PERIOD.
A COLD FRONT WILL APPROACH THE REGION ON WEDNESDAY. THIS WILL HELP
TO INCREASE SHEAR ACROSS OUR AREA AND ENHANCE THUNDERSTORM
DEVELOPMENT. ALTHOUGH 0-6 KM SHEAR WILL ONLY BE AROUND 30 KT...THIS
WOULD BE SUFFICIENT FOR SOME SEVERE STORMS TO DEVELOP. IF THIS
DOES OCCUR...THE MAIN THREAT FROM THESE STORMS WILL BE DAMAGING
WINDS AND LARGE HAIL. THIS SEVERE THREAT WILL BE HIGHLIGHTED IN
THE HWO FOR THE WEDNESDAY INTO WEDNESDAY NIGHT TIME PERIOD. BY
LATE WEDNESDAY NIGHT...CONVECTION WILL SHIFT SOUTHEAST OF OUR AREA
AHEAD OF A COLD FRONT.
HIGH PRESSURE WILL BUILD EASTWARD ACROSS OUR REGION ON
THURSDAY...BRINGING TO THE AREA A DRIER AND MORE STABLE AIRMASS.
EXPECT FAIR CONDITIONS BOTH THURSDAY AND THURSDAY NIGHT. TEMPERATURES
THURSDAY WILL BE IN THE LOW 80S. EXPECT SEASONABLY COOL LOWER 60S
THURSDAY NIGHT.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
REGION WILL FIND ITSELF SPLIT BY A CDFNT AT THE BEGINNING OF THE
PERIOD. THE FRONT WILL BE LOCATED NEAR THE OHIO RIVER AT 12Z
THURSDAY. MODELS QUICKLY PUSH THE FRONT INTO THE APPALACHIANS AND
REPLACE IT WITH HIGH PRESSURE. THIS SHOULD MEAN SOME LINGERING
CONVECTION FOR THE MORNING HOURS OF THURSDAY IN THE EXTREME
SOUTH...WITH DRY CONDITIONS FOR THE N. MODELS DROP AN H5 S/W INTO
LAKE ERIE THURSDAY AFTN...BUT RIGHT NOW IT APPEARS THAT THE S/W WILL
PRODUCE JUST SOME AFTN CLOUDS AND NOT ANY AFTN SHOWERS.
HIGH PRESSURE WILL BUILD IN THURSDAY NIGHT AND WILL HOLD CONTROL
INTO SATURDAY NIGHT. THIS SHOULD ALLOW THE REGION TO BEGIN TO DRY
OUT.
RETURN FLOW BY SUNDAY WILL BRING THE RETURN OF SCT CONVECTION FOR
SUNDAY AND MONDAY. WENT WITH LOW CHC POPS FOR NOW.
HIGHS THURSDAY INTO SATURDAY WILL BE A FEW DEGREES EITHER SIDE OF 80
FOR THE REGION. BY SUNDAY AND MONDAY...HIGHS WILL RISE INTO THE
LOWER 80S. LOWS WILL BE IN THE LOWER 60S FOR THE FIRST HALF OF THE
PERIOD...THEN THE MID 60S FOR THE LATER HALF.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
SHOWERS AND THUNDERSTORMS ARE CONTINUING TO SAG SOUTHEAST ACROSS
CENTRAL OHIO. THERE DOES APPEAR TO BE SOMEWHAT OF A BACK EDGE TO
IT THOUGH WITH JUST SOME VERY SPOTTY SHOWERS FARTHER BACK TO THE
NORTHWEST. THE LATEST RUC AND HRR ARE BOTH SUGGESTING SOME
ADDITIONAL REDEVELOPMENT ACROSS CENTRAL OHIO THROUGH
DAYBREAK. THE 00Z ARW IS ALSO SUGGESTING SOME REGENERATION...BUT
KEEPING IT NORTH OF THE TAF SITES. AS A RESULT...KCMH/KLCK MAY
REMAIN ALONG OR NEAR THE EDGE OF THIS THROUGH DAYBREAK.
MEANWHILE...SHOWERS ARE POPPING UP ACROSS SOUTHERN INDIANA AND
THE GLOBAL MODELS ARE INDICATING SOME OF THESE WILL SAG DOWN TOWARD
KCVG/KLUK THROUGH DAYBREAK. QUITE A BIT OF MODEL VARIANCE AS TO
WHAT WILL OCCUR LATER TODAY INTO TONIGHT. WILL TRY TO ALLOW FOR A
LULL IN THE PCPN FROM LATE MORNING INTO EARLY AFTERNOON...BUT
CONFIDENCE IN THIS IS NOT VERY HIGH AS SOME OF THE HI RES MODELS ARE
HINTING AT PCPN LINGERING THROUGH MUCH OF THE DAY...ESPECIALLY
ACROSS OUR NORTH. HOWEVER...THINK BETTER CHANCE FOR THUNDERSTORMS
WILL BE LATER IN THE DAY AS WE DESTABILIZE THROUGH THE AFTERNOON.
THINK BEST CHANCE FOR REDEVELOP MET WILL BE ALONG A REMNANT
BOUNDARY THAT WILL LIKELY BE ALONG THE I 70 CORRIDOR BY LATE
AFTERNOON...WITH PCPN THEN SAGGING SOUTH TOWARD THE OHIO RIVER
THROUGH THE EVENING.
OUTLOOK...GOOD CHANCE OF THUNDERSTORMS WEDNESDAY AND WEDNESDAY
NIGHT.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...FLASH FLOOD WATCH UNTIL 10 AM EDT THIS MORNING FOR OHZ026-034-
035-042>046-051>056-060>065-073-074.
KY...NONE.
IN...FLASH FLOOD WATCH UNTIL 10 AM EDT THIS MORNING FOR INZ050-058-
059.
&&
$$
SYNOPSIS...LATTO
NEAR TERM...LATTO
SHORT TERM...LATTO
LONG TERM...SITES
AVIATION...JGL
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
135 AM EDT TUE JUL 9 2013
.SYNOPSIS...
A SERIES OF UPPER LEVEL DISTURBANCES WILL RESULT IN A CONTINUED
CHANCE OF THUNDERSTORMS THROUGH MID WEEK. A COLD FRONT WILL PUSH
THROUGH THE AREA WEDNESDAY NIGHT. BUILDING HIGH PRESSURE IN THE
UPPER MIDWEST BEHIND THE FRONT WILL BRING DRIER CONDITIONS FOR
THE REMAINDER OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
HAVE BECOME INCREASINGLY CONCERNED ABOUT HEAVY RAIN/FLASH FLOOD
POTENTIAL FOR THE OVERNIGHT HOURS ACROSS THE NORTHERN HALF OF THE
FORECAST AREA. MODELS ARE SHOWING A LOW LEVEL JET ACROSS NORTHERN
OHIO THAT KEEPS AN AXIS OF MOISTURE TRANSPORT ACROSS THE REGION
THROUGH THE NIGHT. GUIDANCE HAS BEEN DEVELOPING AN EAST-WEST LINE
OF PRECIPITATION WHICH ONCE IT SETS UP MAY NOT MOVE MUCH AS IT
BECOMES PARALLEL TO THE 0-3 KM SHEAR VECTOR. ALTHOUGH IT SHOULD BE
NOTED THAT SOME RECENT RUNS OF THE HRRR AND RAP SUGGEST THAT THE
CONVECTIVE LINE MAY BE ABLE TO SAG SOUTH. ALSO THE WARM CLOUD
DEPTH IS DEEP WHICH WILL MAKE FOR VERY EFFICIENT RAINFALL
PRODUCTION. SOME OF THE REGION ALREADY HAD HEAVY RAINFALL EARLY
MONDAY MORNING WHICH SATURATED THE GROUND. ALL OF THIS SUGGESTS
THAT THERE IS A SUBSTANTIAL THREAT OF FLASH FLOODING AND IT IS
POSSIBLE THAT SOME LOCATIONS COULD SEE SIGNIFICANT IMPACTS
OVERNIGHT. THUS HAVE EXPANDED THE FLASH FLOOD WATCH BACK WEST TO
INCLUDE MOST OF THE MIAMI VALLEY AND PARTS OF THE WHITEWATER
VALLEY.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
MODELS ARE IN DISAGREEMENT WITH THE EVOLUTION OF THE RAIN FROM
TONIGHT. CANNOT REMOVE A CHANCE FOR THUNDERSTORMS IN AN AIRMASS
THAT HAS BEEN EXTREMELY SUPPORTIVE OF THEM FOR THE PAST WEEK OR
MORE. HEAVY RAIN WILL BE A POSSIBILITY WITH ANY OF THESE
STORMS...AND THE CHANCES WILL REALLY INCREASE LATE WEDNESDAY AND
OVERNIGHT AS A DISTINCT COLD FRONT WITH UPPER LEVEL SUPPORT
CROSSES THE AREA. UNTIL THIS TIME...MORE OF THE SAME IS EXPECTED
AND HIGHS WILL GRADUALLY CREEP UPWARDS A DEGREE OR TWO EACH DAY.
NIGHTTIME LOWS WILL ONLY BE MITIGATED TO BE COOLER FROM STORMS
THAT MAY OR MAY NOT BE PRESENT AT TIMES...AT LEAST TUESDAY NIGHT.
OUTSIDE OF THE STORMS...THE AIRMASS WILL RETAIN HIGH DEWPOINTS AND
LIMIT NIGHTTIME DROPOFFS MUCH BELOW 70 DEGREES.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
REGION WILL FIND ITSELF SPLIT BY A CDFNT AT THE BEGINNING OF THE
PERIOD. THE FRONT WILL BE LOCATED NEAR THE OHIO RIVER AT 12Z
THURSDAY. MODELS QUICKLY PUSH THE FRONT INTO THE APPALACHIANS AND
REPLACE IT WITH HIGH PRESSURE. THIS SHOULD MEAN SOME LINGERING
CONVECTION FOR THE MORNING HOURS OF THURSDAY IN THE EXTREME
SOUTH...WITH DRY CONDITIONS FOR THE N. MODELS DROP AN H5 S/W INTO
LAKE ERIE THURSDAY AFTN...BUT RIGHT NOW IT APPEARS THAT THE S/W WILL
PRODUCE JUST SOME AFTN CLOUDS AND NOT ANY AFTN SHOWERS.
HIGH PRESSURE WILL BUILD IN THURSDAY NIGHT AND WILL HOLD CONTROL
INTO SATURDAY NIGHT. THIS SHOULD ALLOW THE REGION TO BEGIN TO DRY
OUT.
RETURN FLOW BY SUNDAY WILL BRING THE RETURN OF SCT CONVECTION FOR
SUNDAY AND MONDAY. WENT WITH LOW CHC POPS FOR NOW.
HIGHS THURSDAY INTO SATURDAY WILL BE A FEW DEGREES EITHER SIDE OF 80
FOR THE REGION. BY SUNDAY AND MONDAY...HIGHS WILL RISE INTO THE
LOWER 80S. LOWS WILL BE IN THE LOWER 60S FOR THE FIRST HALF OF THE
PERIOD...THEN THE MID 60S FOR THE LATER HALF.
&&
.AVIATION /05Z TUESDAY THROUGH SATURDAY/...
SHOWERS AND THUNDERSTORMS ARE CONTINUING TO SAG SOUTHEAST ACROSS
CENTRAL OHIO. THERE DOES APPEAR TO BE SOMEWHAT OF A BACK EDGE TO
IT THOUGH WITH JUST SOME VERY SPOTTY SHOWERS FARTHER BACK TO THE
NORTHWEST. THE LATEST RUC AND HRR ARE BOTH SUGGESTING SOME
ADDITIONAL REDEVELOPMENT ACROSS CENTRAL OHIO THROUGH
DAYBREAK. THE 00Z ARW IS ALSO SUGGESTING SOME REGENERATION...BUT
KEEPING IT NORTH OF THE TAF SITES. AS A RESULT...KCMH/KLCK MAY
REMAIN ALONG OR NEAR THE EDGE OF THIS THROUGH DAYBREAK.
MEANWHILE...SHOWERS ARE POPPING UP ACROSS SOUTHERN INDIANA AND
THE GLOBAL MODELS ARE INDICATING SOME OF THESE WILL SAG DOWN TOWARD
KCVG/KLUK THROUGH DAYBREAK. QUITE A BIT OF MODEL VARIANCE AS TO
WHAT WILL OCCUR LATER TODAY INTO TONIGHT. WILL TRY TO ALLOW FOR A
LULL IN THE PCPN FROM LATE MORNING INTO EARLY AFTERNOON...BUT
CONFIDENCE IN THIS IS NOT VERY HIGH AS SOME OF THE HI RES MODELS ARE
HINTING AT PCPN LINGERING THROUGH MUCH OF THE DAY...ESPECIALLY
ACROSS OUR NORTH. HOWEVER...THINK BETTER CHANCE FOR THUNDERSTORMS
WILL BE LATER IN THE DAY AS WE DESTABILIZE THROUGH THE AFTERNOON.
THINK BEST CHANCE FOR REDEVELOP MET WILL BE ALONG A REMNANT
BOUNDARY THAT WILL LIKELY BE ALONG THE I 70 CORRIDOR BY LATE
AFTERNOON...WITH PCPN THEN SAGGING SOUTH TOWARD THE OHIO RIVER
THROUGH THE EVENING.
OUTLOOK...GOOD CHANCE OF THUNDERSTORMS WEDNESDAY AND WEDNESDAY
NIGHT.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...FLASH FLOOD WATCH UNTIL 10 AM EDT THIS MORNING FOR OHZ026-034-
035-042>046-051>056-060>065-073-074.
KY...NONE.
IN...FLASH FLOOD WATCH UNTIL 10 AM EDT THIS MORNING FOR INZ050-058-
059.
&&
$$
SYNOPSIS...FRANKS
NEAR TERM...
SHORT TERM...FRANKS
LONG TERM...SITES
AVIATION...JGL
AREA FORECAST DISCUSSION
NWS TULSA OK
942 PM CDT WED JUL 10 2013
.DISCUSSION...
STORMS LINGERING FROM THE AFTERNOON OVER WEST CENTRAL AR ARE ON
THE DECLINE DUE TO THE LOSS OF SOLAR HEATING. ONCE THIS ACTIVITY
DIES OFF...THE REMAINDER OF THE NIGHT SHOULD BE MAINLY QUIET.
TOWARD 12Z...THE LATEST RUN OF THE HRRR SUGGESTS WE COULD SEE SOME
HIGH BASED ACCAS SHOWERS AND STORMS...MUCH LIKE THIS MORNING.
UPDATED TEXT PRODUCTS ARE OUT.
LACY
&&
.PREV DISCUSSION... /ISSUED 605 PM CDT WED JUL 10 2013/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
FOR THE 0Z TAFS... VFR CONDITIONS WILL PREVAIL AT ALL TAF SITES
FOR THE ENTIRE 24 HOUR FORECAST PERIOD. ONGOING WIDELY SCATTERED
THUNDERSTORMS WILL CONTINUE ACROSS THE REGION INTO THIS EVENING.
WILL INCLUDE VCTS AT ALL SITES AND WILL USE A TEMPO GROUP FOR
KMLC... WHICH APPEARS LIKELY TO BE AFFECTED BY A STORM OVER THE
NEXT HOUR OR SO.
PREV DISCUSSION... /ISSUED 311 PM CDT WED JUL 10 2013/
DISCUSSION...
ANOTHER HOT DAY WELL UNDERWAY ACROSS EASTERN OKLAHOMA AND
NORTHWEST ARKANSAS EVEN AS A COLD FRONT HAS MOVED INTO THE
AREA. THE COLD FRONT CURRENTLY EXTENDS FROM NEAR KSTL TO
NEAR KRVS WITH ANOTHER WEAK TROF OF LOW PRESSURE ACROSS
NORTHWEST ARKANSAS. SHOWERS AND A FEW THUNDERSTORMS HAVE DEVELOPED
THIS AFTERNOON IN THE VICINITY OF THE FRONTAL BOUNDARY. THE CHANCES
OF SHOWERS AND THUNDERSTORMS WILL CONTINUE NEAR THE BOUNDARY INTO
THIS EVENING. THERE IS ALSO SOME POTENTIAL FOR THE ACTIVITY TO
CONTINUE INTO THE OVERNIGHT HOURS. THERE IS THE POTENTIAL FOR
SOME OF THE STORMS TO BECOME SEVERE LATE THIS AFTERNOON AND EVENING
WITH WIND GUSTS APPROACHING 80 MPH WITH THE STRONGEST STORMS.
WILL TRIM SOME COUNTIES OFF OF THE HEAT ADVISORY AND LET THE
EXCESSIVE HEAT WARNING FOR TULSA COUNTY EXPIRE AT 01Z. WILL KEEP
THE COUNTIES SOUTH OF THE BOUNDARY IN A HEAT ADVISORY THAT WILL
CONTINUE THROUGH THURSDAY AFTERNOON. MAY SEE ISOLATED SHOWERS
AND THUNDERSTORMS ACROSS THE AREA ON THURSDAY AS THE BOUNDARY
LINGERS.
WILL KEEP THE FORECAST FROM FRIDAY INTO THE MIDDLE OF NEXT
WEEK DRY WITH TEMPERATURES AT OR SLIGHTLY ABOVE NORMAL FOR
THIS TIME OF YEAR. THE MODELS CONTINUE TO SHOW THE UPPER LEVEL
LOW CURRENTLY AFFECTING SOUTH FLORIDA MOVING WEST ACROSS SOUTH
TEXAS OVER THE WEEKEND SHOVING THE UPPER LEVEL RIDGE CURRENTLY
OVER OUR AREA TO THE NORTH. THE UPPER LEVEL LOW LOOKS TO BE TOO
FAR SOUTH TO BRING ANY SHOWER OR THUNDERSTORMS TO THE AREA.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 75 96 74 97 / 20 20 0 10
FSM 76 97 73 94 / 30 20 0 10
MLC 75 100 75 97 / 20 20 20 10
BVO 72 94 70 96 / 20 20 0 10
FYV 70 92 67 90 / 20 20 10 10
BYV 70 90 65 88 / 20 20 10 10
MKO 75 97 73 95 / 20 20 0 10
MIO 72 93 69 93 / 20 20 0 10
F10 75 98 75 96 / 20 20 20 10
HHW 76 99 75 97 / 20 20 20 10
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...HEAT ADVISORY UNTIL 7 PM THURSDAY FOR OKZ049-OKZ053-OKZ064-
OKZ065-OKZ066-OKZ070-OKZ071-OKZ073-OKZ074-OKZ075-OKZ076.
AR...NONE.
&&
$$
LONG TERM....30
AREA FORECAST DISCUSSION
NWS NORMAN OK
849 PM CDT WED JUL 10 2013
.UPDATE...
UPDATED POPS THROUGH 06Z
&&
.DISCUSSION...
STORMS HAVE SLOWLY WEAKENED OVER THE PAST TWO HOURS...WITH
ISOLATED SHOWERS/THUNDER REMAINING ACROSS FAR NWRN OK. TRIMMED
BACK POPS ACROSS CENTRAL OK TO ACCOUNT FOR THIS. TO THE NW...A
DECENT MCS HAS STARTED TO DEVELOP ACROSS SERN CO AND FAR SWRN KS
THIS EVENING. THIS ACTIVITY IS EXPECTED TO SLOWLY MOVE S/SE
THROUGH THE EVENING AND OVERNIGHT.
FAR NWRN AND NRN OK WILL HAVE THE GREATEST CHANCES FOR
PRECIPITATION AS WILL THE PANHANDLES...AS CONDITIONS ARE LESS
FAVORABLE ACROSS CENTRAL AND SRN OK INTO WRN N TX FOR MCS
MAINTENANCE. MUCAPE IN THE 1000-500MB LAYER IS PALTRY...ACROSS
CENTRAL AND WRN OK...600 TO 1000 J/KG OVERNIGHT. THIS SCENARIO IS
SUPPORTED BY HRRR WITH OVERALL CONVECTION WEAKENING OVERNIGHT
ACROSS MUCH OF OKLAHOMA. HOWEVER...THERE REMAINS A CHANCE FOR
SCATTERED SHOWERS AND THUNDERSTORMS ACROSS PORTIONS OF THE AREA
THROUGH SUNRISE AS THE WEAK BOUNDARY/FRONT REMAINS POSITIONED E/W
ACROSS THE STATE.
JTK
&&
.PREV DISCUSSION... /ISSUED 641 PM CDT WED JUL 10 2013/
AVIATION...00Z TAF ISSUANCE...
TRICKY AVIATION FORECAST OVER THE NEXT 12 HOURS. SCATTERED
CONVECTION WILL CONTINUE TO IMPACT NWRN OK. FOR THE MOMENT...WILL
CONTINUE TO RUN VCTS FOR KGAG AND KWWR THROUGH 03Z. EXPECT ONGOING
STORMS ACROSS SWRN KS AND SERN CO TO FORM INTO A COMPLEX AND TRACK
SEWRD INTO NRN OK. CEILINGS WILL LIKELY HOLD AT VFR...BUT MVFR
CAN BE EXPECTED WITH ANY SITE DIRECTLY IMPACTED BY A SHOWER OR
THUNDERSTORM. WINDS WILL CALM SLIGHTLY...OUT OF THE S/SE...ACROSS
MUCH OF THE REGION DUE TO THE WEAK BOUNDARY/FRONT EXTENDING ACROSS
THE STATE. WINDS WILL REMAIN OUT OF THE E/SE THROUGH THE END OF
THE PERIOD WITH BKN TO SCT SKIES PERSISTING THROUGH 00Z TOMORROW
FOR NEARLY ALL SITES.
JTK
PREV DISCUSSION... /ISSUED 343 PM CDT WED JUL 10 2013/
DISCUSSION...
THE MAIN STORY FOR THE REMAINDER OF THE WEEK WILL BE DANGEROUS
HEAT...WHICH WILL LAST THROUGH AT LEAST FRIDAY.
FOR THE REMAINDER OF TODAY...ISOLATED TO WIDELY SCATTERED STORMS
HAVE DEVELOPED ALONG A WEAK SFC FRONT/OUTFLOW BOUNDARY OVER NORTH
CENTRAL OKLAHOMA. ADDITIONAL ACTIVITY IS EXPECTED TO FORM ACROSS
WESTERN KS INTO WEST TX THROUGH THIS EVENING...POTENTIALLY MOVING
INTO FAR NORTHWEST OKLAHOMA THROUGH 03Z. WHILE LITTLE TO NO WIND
SHEAR IS PRESENT...PULSE VARIETY THUNDERSTORMS ARE EXPECTED. WITH
LARGE TEMPERATURE DEWPOINT SPREADS...EXPECT THE STRONGEST STORMS
MAY PRODUCE DAMAGING DOWNBURST WINDS OF 60 TO 70 MPH. THOUGH GUSTY
WINDS WILL BE LIKELY NEAR ANY STORM THAT DEVELOPS. OUTSIDE OF RAIN
COOLED AREAS...TEMPERATURES WILL HOVER AROUND 100 DEGREES THROUGH
THE EVENING...WITH GRADUAL COOLING BY MIDNIGHT. MOST SHOWER/STORM
ACTIVITY WILL HAVE ENDED BY THIS TIME.
THOUGH TEMPERATURES MAY COME IN A BIT COOLER BOTH TOMORROW AND
FRIDAY THAN TODAY...COMBINATION OF INCREASING LOW LEVEL MOISTURE
AND AFTERNOON HIGHS NEAR 100 DEGREES WILL LEAD TO DANGEROUS HEAT.
HEAT INDICES BOTH TOMORROW AND FRIDAY WILL TOP OUT BETWEEN 103 AND
110 DEGREES...WITH OVERNIGHT LOWS ONLY FALLING TO AROUND 80
DEGREES. WITH THIS IN MIND...HAVE OPTED TO EXTEND THE HEAT
ADVISORY BOTH IN AREA AND TIME TO COVER MUCH OF CENTRAL AND
SOUTHERN OKLAHOMA. PLEASE FOLLOW HEAT SAFETY MEASURES THROUGH THE
REMAINDER OF THE WEEK...AS THESE CONDITIONS CAN PROVE FATAL IF NOT
ADDRESSED PROPERLY.
BY THIS WEEKEND...A BROAD UPPER TROUGH WILL MOVE FROM EAST TO
WEST ALONG THE NRN GULF COAST. THIS SHOULD BRING HEIGHTS DOWN A
BIT...LEADING TO SLIGHTLY LESS HOT CONDITIONS FROM THE WEEKEND
INTO NEXT WEEK. THOUGH AFTERNOON HIGHS WILL GENERALLY REMAIN IN
THE 93 TO 100 DEGREE RANGE. WITH WEAK UPPER FORCING ALOFT...AND
IMPROVING DEEP MOISTURE...EXPECT THIS FEATURE MAY ALSO LEAD TO
ISOLATED SHOWER AND THUNDERSTORM ACTIVITY OVER SOUTHERN PORTIONS
OF OKLAHOMA AND NORTH TEXAS FOR THE EARLY TO MIDDLE PART OF NEXT
WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 77 99 75 98 / 30 20 20 0
HOBART OK 79 103 76 102 / 20 20 10 10
WICHITA FALLS TX 79 104 77 103 / 10 20 20 0
GAGE OK 75 98 74 101 / 60 10 10 0
PONCA CITY OK 77 95 72 97 / 30 20 10 10
DURANT OK 77 100 76 100 / 20 20 20 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...HEAT ADVISORY UNTIL 7 AM CDT SATURDAY FOR OKZ007-008-012-013-
018>020.
HEAT ADVISORY UNTIL 9 PM CDT THIS EVENING FOR OKZ006-011.
HEAT ADVISORY UNTIL 7 AM CDT SATURDAY FOR OKZ024>032-039>043-
045>048-050>052.
TX...NONE.
&&
$$
17/04
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
744 AM EDT TUE JUL 9 2013
.SYNOPSIS...
A BERMUDA HIGH ANCHORED OFF THE EASTERN SEABOARD WILL CONTINUE TO
FEED VERY WARM AND HUMID AIR NORTHWARD INTO THE COMMONWEALTH.
DAILY CHANCES OF SHOWERS AND THUNDERSTORMS WILL PERSIST UNTIL A
COLD FRONT PASSES THURSDAY.
&&
.NEAR TERM /UNTIL 4 PM THIS AFTERNOON/...
BROAD SHORT WAVE TROUGH WHICH SEEMS UNDERDONE BY THE MDLS IS
DROPPING ESE FROM OHIO EARLY THIS MORNING. MID LEVEL WINDS
INCREASE FROM THE SW SLIGHTLY THIS MORNING...AND MOISTURE POOLING
AT THE AXIS OF THE TROUGH WILL SLIDE ACROSS THE CWA FROM W-E AS
MAINLY LIGHT SHOWERS AND WIDELY SCT/EMBEDDED THUNDER. HEAVIER RAIN
ON A TRACK TO MOVE TO THE SOUTH OF THE AREA. HRRR SEEMS TO HAVE A
GOOD HANDLE ON RECENT TRENDS. IT PORTRAYS THE DEATH OF MUCH OF
THIS FIRST BATCH OF LIGHT RAIN AS IT MOVES TO THE EAST...THEN A
RE-DEVELOPMENT OF CONVECTION AS DAYTIME HEATING COMBINES WITH
BREAKS IN THE CLOUD COVER TO BUBBLE UP SHRA/TSRA. WITH CLOUDS AND
SCT/NMRS SHOWERS AROUND...WILL KEEP MAXE TEMPS LOOKING LIKE
YESTERDAY/MON. DEWPOINTS ALSO MOVE LITTLE SO ANOTHER SEASONAL JULY
DAY IS IN STORE.
&&
.SHORT TERM /4 PM THIS AFTERNOON THROUGH 6 PM WEDNESDAY/...
THE SHORT WAVE PUSHES TO THE EAST THIS EVENING AND A DECREASE IN
SHRA/TSRA IS EXPECTED FOR MOST OF THE OVERNIGHT HOURS. WILL JUST
LEAVE IN SCT/ISOLD WORDING FOR NOW. HEIGHTS DROP THROUGH THE
NIGHT...THOUGH. THIS OCCURS AS A BROADER AND MORE-SYNOPTIC SCALE
TROUGH AXIS NEARS FROM THE GREAT LAKES/UPPER MIDWEST. THE MOISTURE
PLUME PUSHES RIGHT BACK INTO THE AREA LATE TONIGHT AND HANGS OUT
OVERHEAD THROUGH THE END OF THE PERIOD. A COOL FRONT REACHES THE
LOWER LAKES LATE WED. ALL THIS PUTS THE AREA IN THE WARM SECTOR
AND ALLOWS THE SERN COS TO MAKE ANOTHER RUN AT 90F. THE CLOUDS
WILL BE THE TEMPERING FACTOR ON WEDNESDAY...KNOCKING A FEW DEGS
OFF THE POTENTIAL MAXES. THEY WILL ALSO PLAY A ROLE IN THE
POTENTIAL FOR SEVERE WEATHER ON WEDNESDAY AFTN/EVENING. CAPES O/O
OF 2000 ARE POSSIBLE...BUT MAY NOT BE REALIZED. ALSO...WIND FIELD
IS NOT ALL THAT STRONG AS SPC POINTS OUT.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
COOL FRONT SHOULD PUSH INTO THE AEA EARLY WED NIGHT AND MIGHT
CLEAR THE SERN COS BY THURSDAY SUNRISE. HOWEVER...POPS IN THE CHC
RANGE STILL A STRONG FORECAST FOR THE SERN HALF OF THE AREA LATE WED
NIGHT AND ALL THURS DUE TO UNCERTAINTY OF HOW FAR S THE DRIER AIR
WILL BE ABLE TO NUDGE THE CONVECTION.
MEDIUM RANGE MODEL AND ENSEMBLE GUIDANCE CONTINUES TO ADVERTISE
ANOTHER ANOMALOUS MERIDIONAL LARGE SCALE PATTERN EARLY IN THE
PERIOD...AS TROUGHING/UPPER LOW DROPS SOUTHWARD ALONG/WEST OF THE
APPALACHIANS...AND FOUR CORNERS RIDGE MAINTAINS ITS POSITION. THE
AMPLIFIED FLOW OVER THE CONUS SHOULD EVOLVE AND REVERT BACK TO A
MORE TYPICAL SUMMERTIME CONFIGURATION DURING THE SECOND HALF OF
THE PERIOD...AS THE JET STREAM RETREATS NORTHWARD TO THE
U.S./CANADIAN BORDER AND LARGE SUBTROPICAL RIDGE TAKES UP
RESIDENCE OVER MUCH OF THE LOWER 48.
IN TERMS OF SENSIBLE WX IMPACTS...A SURGE OF MUCH DRIER/BELOW NORMAL
PWAT AIR SHOULD FOLLOW BEHIND THE COLD FROPA ON THURSDAY. THIS
SHOULD PROVIDE A BRIEF BREAK IN THE HUMID/MUGGY CONDITIONS LATER
THIS WEEK. THE FRONTAL BOUNDARY APPEARS TO STALL-OUT OVER THE SRN
MID-ATLC STATES BEFORE DRIFTING BACK TO THE WEST TOWARD THE
APPALACHIANS...INTERCEPTING A MODEST /NEAR-NORMAL PWATS/ MOISTURE
FLOW AROUND THE BERMUDA HIGH. AS SUCH...LOOK FOR TEMPERATURES AND
TREND UPWARD INTO NEXT WEEK ACCOMPANIED BY RETURNING SUMMERTIME
HUMIDITY.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
BANDS OF MAINLY LIGHT SHOWERS ARE MOVING ACROSS CENTRAL PA MAKING
FOR A MOIST START TO THE MORNING. WIDESPREAD MVFR CIGS AND POOR
VSBYS IN FOG WILL PERSIST THROUGH 14Z MOST TAF SITES.
PREDOMINANTLY VFR CONDS ARE LIKELY LATER THIS MORNING AND INTO
EARLY AFTN. HOWEVER...ISOLD LATE DAY THUNDERSTORM IMPACTS ARE
POSSIBLE IN ASSOCIATION WITH LINGERING TROUGH OF LOW PRES OVR THE
AREA.
OUTLOOK...
WED...AM LOW CIGS POSS NW MTNS. SCT TSRA IMPACTS POSSIBLE.
THU...AM LOW CIGS POSS W MTNS. SCT TSRA IMPACTS POSSIBLE.
FRI-SAT...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...STEINBUGL
AVIATION...FITZGERALD/GARTNER
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
439 AM EDT TUE JUL 9 2013
.SYNOPSIS...
A BERMUDA HIGH ANCHORED OFF THE EASTERN SEABOARD WILL CONTINUE TO
FEED VERY WARM AND HUMID AIR NORTHWARD INTO THE COMMONWEALTH.
DAILY CHANCES OF SHOWERS AND THUNDERSTORMS WILL PERSIST UNTIL A
COLD FRONT PASSES THURSDAY.
&&
.NEAR TERM /UNTIL 4 PM THIS AFTERNOON/...
BROAD SHORT WAVE TROUGH WHICH SEEMS UNDERDONE BY THE MDLS IS
DROPPING ESE FROM OHIO EARLY THIS MORNING. MID LEVEL WINDS
INCREASE FROM THE SW SLIGHTLY THIS MORNING...AND MOISTURE POOLING
AT THE AXIS OF THE TROUGH WILL SLIDE ACROSS THE CWA FROM W-E AS
MAINLY LIGHT SHOWERS AND WIDELY SCT/EMBEDDED THUNDER. HEAVIER RAIN
ON A TRACK TO MOVE TO THE SOUTH OF THE AREA. HRRR SEEMS TO HAVE A
GOOD HANDLE ON RECENT TRENDS. IT PORTRAYS THE DEATH OF MUCH OF
THIS FIRST BATCH OF LIGHT RAIN AS IT MOVES TO THE EAST...THEN A
RE-DEVELOPMENT OF CONVECTION AS DAYTIME HEATING COMBINES WITH
BREAKS IN THE CLOUD COVER TO BUBBLE UP SHRA/TSRA. WITH CLOUDS AND
SCT/NMRS SHOWERS AROUND...WILL KEEP MAXE TEMPS LOOKING LIKE
YESTERDAY/MON. DEWPOINTS ALSO MOVE LITTLE SO ANOTHER SEASONAL JULY
DAY IS IN STORE.
&&
.SHORT TERM /4 PM THIS AFTERNOON THROUGH 6 PM WEDNESDAY/...
THE SHORT WAVE PUSHES TO THE EAST THIS EVENING AND A DECREASE IN
SHRA/TSRA IS EXPECTED FOR MOST OF THE OVERNIGHT HOURS. WILL JUST
LEAVE IN SCT/ISOLD WORDING FOR NOW. HEIGHTS DROP THROUGH THE
NIGHT...THOUGH. THIS OCCURS AS A BROADER AND MORE-SYNOPTIC SCALE
TROUGH AXIS NEARS FROM THE GREAT LAKES/UPPER MIDWEST. THE MOISTURE
PLUME PUSHES RIGHT BACK INTO THE AREA LATE TONIGHT AND HANGS OUT
OVERHEAD THROUGH THE END OF THE PERIOD. A COOL FRONT REACHES THE
LOWER LAKES LATE WED. ALL THIS PUTS THE AREA IN THE WARM SECTOR
AND ALLOWS THE SERN COS TO MAKE ANOTHER RUN AT 90F. THE CLOUDS
WILL BE THE TEMPERING FACTOR ON WEDNESDAY...KNOCKING A FEW DEGS
OFF THE POTENTIAL MAXES. THEY WILL ALSO PLAY A ROLE IN THE
POTENTIAL FOR SEVERE WEATHER ON WEDNESDAY AFTN/EVENING. CAPES O/O
OF 2000 ARE POSSIBLE...BUT MAY NOT BE REALIZED. ALSO...WIND FIELD
IS NOT ALL THAT STRONG AS SPC POINTS OUT.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
COOL FRONT SHOULD PUSH INTO THE AEA EARLY WED NIGHT AND MIGHT
CLEAR THE SERN COS BY THURSDAY SUNRISE. HOWEVER...POPS IN THE CHC
RANGE STILL A STRONG FORECAST FOR THE SERN HALF OF THE AREA LATE WED
NIGHT AND ALL THURS DUE TO UNCERTAINTY OF HOW FAR S THE DRIER AIR
WILL BE ABLE TO NUDGE THE CONVECTION.
MEDIUM RANGE MODEL AND ENSEMBLE GUIDANCE CONTINUES TO ADVERTISE
ANOTHER ANOMALOUS MERIDIONAL LARGE SCALE PATTERN EARLY IN THE
PERIOD...AS TROUGHING/UPPER LOW DROPS SOUTHWARD ALONG/WEST OF THE
APPALACHIANS...AND FOUR CORNERS RIDGE MAINTAINS ITS POSITION. THE
AMPLIFIED FLOW OVER THE CONUS SHOULD EVOLVE AND REVERT BACK TO A
MORE TYPICAL SUMMERTIME CONFIGURATION DURING THE SECOND HALF OF
THE PERIOD...AS THE JET STREAM RETREATS NORTHWARD TO THE
U.S./CANADIAN BORDER AND LARGE SUBTROPICAL RIDGE TAKES UP
RESIDENCE OVER MUCH OF THE LOWER 48.
IN TERMS OF SENSIBLE WX IMPACTS...A SURGE OF MUCH DRIER/BELOW NORMAL
PWAT AIR SHOULD FOLLOW BEHIND THE COLD FROPA ON THURSDAY. THIS
SHOULD PROVIDE A BRIEF BREAK IN THE HUMID/MUGGY CONDITIONS LATER
THIS WEEK. THE FRONTAL BOUNDARY APPEARS TO STALL-OUT OVER THE SRN
MID-ATLC STATES BEFORE DRIFTING BACK TO THE WEST TOWARD THE
APPALACHIANS...INTERCEPTING A MODEST /NEAR-NORMAL PWATS/ MOISTURE
FLOW AROUND THE BERMUDA HIGH. AS SUCH...LOOK FOR TEMPERATURES AND
TREND UPWARD INTO NEXT WEEK ACCOMPANIED BY RETURNING SUMMERTIME
HUMIDITY.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
LATE EVENING RADAR LOOP SHOWS A DWINDLING AREA OF SHRA ACROSS THE
SUSQ VALLEY IN VICINITY OF A DEPARTING UPPER LVL LOW PRES SYSTEM.
JUST A SLIGHT CHC OF A BRIEF VSBY REDUCTION FROM THESE SHRA THRU
04Z AT IPT...MDT AND LNS. BRIEF CLEARING AHEAD OF NEXT LOW PRES
SYSTEM COULD RESULT IN SOME FOG AFTER MIDNIGHT...MAINLY IN THOSE
LOCATIONS THAT RECEIVED RAIN EARLIER THIS EVENING...SUCH AS UNV.
NEXT LOW PRES SYSTEM APPROACHING FROM THE GRT LKS WILL LIKELY
BRING ANOTHER ROUND OF SHRA TO THE AREA EARLY TUE AM. THICKENING
CLOUD COVER AHEAD OF THIS FEATURE SHOULD PUT A BREAK ON THE
RADIATIONAL COOLING AND FOG FORMATION AFTER ABOUT 06Z-08Z.
HOWEVER...MVFR VSBYS STILL POSSIBLE LATE TONIGHT IN ANY HEAVIER
SHOWERS.
MODEL GUIDANCE SUGGESTS LOW PRES TROUGH AND ASSOC SHOWERS WILL
IMPACT THE ENTIRE AREA LATE TUE AM WITH LIMITED RESTRICTIONS. A
MOIST SW FLOW ASCENDING THE NW MTNS COULD PRODUCE SOME PERSISTENT
MVFR CIGS AT BFD BTWN 12Z-18Z TUESDAY. ELSEWHERE...PREDOMINANTLY
VFR CONDS ARE LIKELY BY NOON. HOWEVER...ISOLD LATE DAY THUNDERSTORM
IMPACTS ARE POSSIBLE IN ASSOCIATION WITH LINGERING TROUGH OF LOW
PRES OVR THE AREA.
OUTLOOK...
WED...AM LOW CIGS POSS NW MTNS. SCT TSRA IMPACTS POSSIBLE.
THU...AM LOW CIGS POSS W MTNS. SCT TSRA IMPACTS POSSIBLE.
FRI-SAT...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...STEINBUGL
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1048 AM CDT TUE JUL 9 2013
.UPDATE...REST OF TODAY
MAIN FORECAST CHALLENGE TODAY IS WHETHER OR NOT WE WILL HAVE
ADDITIONAL ISO/SCT SHOWER AND STORM DEVELOPMENT LATER TODAY ACROSS
NORTHERN/NORTHEASTERN SD. LAST NIGHTS ACTIVITY IS WELL EAST OF THE
REGION AND CURRENTLY AFFECTING MN/WI. ALTHOUGH...MAIN UPPER LEVEL
WAVE IS STILL SPINNING ACROSS FAR SOUTHERN CANADA WITH THE
SHORTWAVE ENERGY EXPECTED TO MOVE EAST ACROSS THE DAKOTAS TODAY
INTO THIS EVENING. THERE HAVE BEEN A FEW SPOTTY SHOWERS ACROSS
CENTRAL SD...NORTHWEST SD AND SOUTHWEST ND. SFC FRONT HAS CLEARED
THE CWA SO WILL BE HARD TO FOCUS ANYTHING AT THE SFC. 12Z NAM
ALONG WITH THE LATEST RUN OF THE HRRR KEEPS THINGS COMPLETELY DRY
TODAY...WITH ONLY A FEW ISO SHOWERS MOVING SOUTHEAST INTO THE AREA
SHORTLY AFTER 00Z THIS EVENING. OTHER HI-RES MESOSCALE MODELS SHOW
A FEW WDLY SCT STORMS DEVELOPING LATER TODAY. THE LATEST HRRR RUN
IS DEPICTING THE CURRENT SITUATION VERY NICELY AND STARTING TO
THINK IT MAY BE ON TO SOMETHING. HEDGED A BIT ON THE DRY SIDE FOR
POPS TODAY BUT DID NOT WANT TO GO COMPLETELY DRY BASED ON THE
UPPER WAVE ALONE...AND THE FACT THAT ITS ENERGY STILL HAS TO SWING
THROUGH THE REGION LATER TODAY. A COUPLE LIGHT SHOWERS ARE ONGOING
ALONG THE ND/SD BORDER TO THE NORTHWEST. ALSO...SFC DEWPOINTS ARE
STILL IN THE 60S. CANNOT COMPLETELY RULE OUT SOMETHING LATER TODAY
BUT NOT REAL EXCITED ABOUT CHANCES AT THIS POINT. IF
ANYTHING...EXPECT IT TO BE ISO/WDLY SCT.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TUESDAY THROUGH THURSDAY
MAIN WEATHER CHALLENGE IN THE SHORT TERM IS PRECIP CHANCES TODAY.
MODELS ARE A LITTLE SLOW MOVING OVERNIGHT CONVECTION ASSOCIATED
WITH A TROF OF LOW PRESSURE THROUGH. THIS IS HAVING RESIDUAL
EFFECTS ON THE QPF FIELD THIS MORNING. LEFT IN SOME POPS ACROSS
THE FAR EAST. STUCK CLOSER TO HI-RES MODELS WHICH HAVE A MOSTLY
DRY MORNING ACROSS THE AREA. THE SFC COLD FRONT SWEEPS INTO THE
EAST THIS AFTERNOON BRINGING CHANCES FOR MORE STORMS. BIGGEST
FORECAST CHALLENGE WITH THIS ROUND OF STORMS IS HOW FAR WEST THEY
WILL EXPAND. FOR NOW HAVE POPS CONFINED TO EAST OF THE JAMES RIVER
VALLEY AS INDICATED ON THE HRRR.
HIGH PRESSURE BUILDS IN TUESDAY NIGHT AND WEDNESDAY. HIGH SHIFTS
TO THE SOUTH AND EAST WEDNESDAY EVENING AHEAD OF ANOTHER TROF.
MODELS INDICATE INCREASED INSTABILITY AHEAD OF THE TROF WITH THE
GFS RAMPING UP THE LLJ WEST OF THE MISSOURI RIVER. KEPT SLIGHT
CHANCE POPS ACROSS THE SOUTHWEST CWA WED NIGHT...BUT IF THE LLJ
PANS OUT MAY NEED TO EXPAND THE POPS NORTH.
TEMPS WILL BE SUPPRESSED BEHIND THIS INITIAL TROF WITH HIGHS IN
THE LOWER 80S TODAY AND WEDNESDAY. AHEAD OF THE NEXT TROF
SOUTHERLY FLOW WILL BOOST TEMPS BACK INTO THE MID 80S TO LOWER 90S
ON THURSDAY.
.LONG TERM...THURSDAY NIGHT THROUGH MONDAY
THE MODELS ALL SHOW GOOD AGREEMENT THROUGH THE LONG TERM WITH THE
UPPER LEVEL FLOW PATTERN ACROSS OUR REGION. THE PERIOD STARTS OUT
WITH A SHARP 50H RIDGE AXIS EXTENDING ACROSS OUR REGION AND INTO
SOUTHERN CANADA WITH LOW PRESSURE TROUGHING ALONG THE PACIFIC
NORTHWEST COAST. THIS UPPER RIDGE WILL FLATTEN OUT DURING THE LONG
TERM AS THE WEST COAST TROUGHING MOVES ALONG THE NORTHERN US BORDER
FROM SATURDAY THROUGH SUNDAY. A BROAD AREA OF UPPER LEVEL HIGH
PRESSURE WILL THEN EXTEND ACROSS MOST OF THE SOUTHERN US THROUGH
MONDAY WITH OUR REGION ON THE NORTHERN EDGE. FRIDAY WILL STILL BE
THE WARMEST DAY IN THE LONG TERM UNDER THE UPPER LEVEL RIDGE WITH
TEMPERATURES APPROACHING 100 DEGREES ON FRIDAY AFTERNOON SOUTHWEST
IN THE CWA. TEMPERATURES WILL REMAIN ABOVE NORMAL THROUGH THE
WEEKEND IN THE MID 80S TO THE LOWER 90S AND MAY BE JUST IN THE 80S
ON MONDAY. HAVE CHANCES OF STORMS FROM MAINLY FRIDAY NIGHT THROUGH
SUNDAY NIGHT ACROSS THE CWA WITH THE UPPER LEVEL LOW PRESSURE
TROUGH SLIDING ACROSS THE REGION ALONG WITH A SURFACE BOUNDARY
PUSHING THROUGH.
&&
.AVIATION...
12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
VFR CONDITIONS ARE EXPECTED AT ALL TERMINALS THROUGH TODAY AND
TONIGHT.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...TMT
SHORT TERM...WISE
LONG TERM...MOHR
AVIATION...MOHR
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS MIDLAND/ODESSA TX
1222 AM CDT TUE JUL 9 2013
.DISCUSSION...
SEE 06 AVIATION DISCUSSION BELOW.
&&
.AVIATION...
GUSTY SOUTH TO SOUTHEAST WINDS WILL DIMINISH IN STRENGTH OVER THE
NEXT FEW HOURS. WINDS WILL ONCE AGAIN BECOME GUSTY AT MOST
LOCATIONS MID MORNING TUESDAY. THERE IS A SLIGHT POSSIBILITY OF
MVFR CEILINGS AT MAF AND FST FOR EARLY TUESDAY MORNING BUT
CONFIDENCE REMAINS LOW.
&&
PREV DISCUSSION... /ISSUED 229 PM CDT MON JUL 8 2013/
DISCUSSION...
AN UPPER LEVEL DISTURBANCE PASSING BY TO THE SOUTH ACROSS THE BIG
BEND COULD GENERATE ISOLATED THUNDERSTORMS THIS EVENING ACROSS
WEST TEXAS PER CUMULUS FIELD AND LATEST RUC GUIDANCE. ANY ACTIVITY
SHOULD DIE THIS EVENING WITH LOSS OF HEATING. THIS DISTURBANCE
IS FORECAST TO CONTINUE TO SLOWLY TRACK WESTWARD ACROSS NORTHERN
MEXICO TUESDAY AND TUESDAY EVENING WITH ISOLATED TO WIDELY SCATTERED
SHOWERS AND THUNDERSTORMS POSSIBLE AGAIN ACROSS THE BIG BEND...DAVIS
MOUNTAINS AND LOWER TRANS PECOS REGION CLOSEST TO THE TRACK OF
DISTURBANCE. BEYOND TUESDAY A SPRAWLING UPPER LEVEL HIGH PRESSURE
AREA ACROSS THE PLAINS AND ROCKIES SHOULD REGAIN FIRM CONTROL OF
THE REGION AND PRECIPITATION CHANCES WILL BE VERY LOW. THE NEXT
CHANCE OF CONVECTION APPEARS TO BE NEXT SUNDAY AND MONDAY AS
ANOTHER DISTURBANCE TRACKS WESTWARD ACROSS THE GULF AND MEXICO.
HIGH TEMPERATURES ARE EXPECTED TO BE NEAR NORMAL THROUGH WEDNESDAY
WITH ABOVE NORMAL TEMPERATURES EXPECTED THURSDAY THROUGH SATURDAY.
&&
.MAF WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.
&&
$$
99
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
815 PM EDT WED JUL 10 2013
.SYNOPSIS...
A DEEPENING UPPER TROUGH ACROSS THE GREAT LAKES WILL PUSH A COLD
FRONT INTO THE REGION THURSDAY. DISTURBANCES IN ADVANCE OF THIS
TROUGH WILL RESULT IN SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS TODAY THROUGH THURSDAY ACROSS THE REGION. BEHIND THE
COLD FRONT...COOLER...DRIER CONDITIONS ARE EXPECTED FOR FRIDAY
INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 800 PM EDT WEDNESDAY...
STORMS THIS EVENING HAVE BEEN VERY RAIN EFFICIENT WITH RATES OF 4
INCHES AN HOUR. THE ROANOKE REGIONAL AIRPORT RECEIVED 3.39 INCHES
OF RAIN IN ABOUT AN HOURS TIME FRAME...3.88 SO FAR FOR THE DAY...
AND NOT A GOOD MIX WHEN YOU FOCUS IT ON-TOP OF ASSFAULT AND
CONCRETE...WHICH TENDS TO MAXIMIZE THE RUNOFF. WATER RESCUES
SEEMED TO BECOME COMMON PLACE THERE FOR AN HOUR OR TWO. THE
ROANOKE RIVER JUMPED 5 TO 8 FEET JUST FROM THE LOCAL RUNOFF.
LOOKING FOR AN EXAMPLE OF A FLASH FLOOD... THERE YA GO.
SCATTERED SHOWERS AND STORMS WILL CONTINUE TO CONVERGE ON THE
PIEDMONT THROUGH THE EVENING HOURS WHERE THE ATMOSPHERE HAS NOT
BEEN WORKED OVER YET...CAPES STILL 1500-2000 J/KG THERE. THE LINE
OF STORMS OVER WV SHOULD WEAKEN AS THEY CROSS THE MOUNTAINS PER
STABLE AIR THAT HAS BEEN CREATED BY THE STORMS THAT OCCURRED
OVER THE CENTRAL AND WESTERN PART OF OUR CWA ALREADY. MAY SEE A
WIND GUST OF 20-30 KTS AS THE GUST FRONT ENTERS OUR WRN
COUNTIES...BUT THINK THE BIGGEST THING WE WILL HAVE TO WORRY ABOUT
IS POTENTIAL FOR ANOTHER BURST OF RAINFALL.
SURFACE COLD FRONT IS EXPECTED TO CROSS THE FORECAST AREA
THURSDAY. NOT CONFIDENT ON HOW MUCH STORM ACTIVITY WILL DEVELOP
ALONG THE FRONT PER CONVECTIVE DEBRIS THAT WILL BE LEFT IN PLACE
FROM THIS EVENINGS STORMS. PWATS WILL REMAIN HIGH...BUT THE CAPE
WILL BE DEPENDANT ON HOW QUICK THE CLOUDS BREAK THURSDAY MORNING.
WITH PWATS RANGING FROM 1.70 TO 2.0 INCHES AND A SLOW STORM
MOTION...WILL LEAVE FLASH FLOOD WATCH AS IS. FFG VALUES REMAIN
VERY LOW FROM RECENT HEAVY RAINFALL...AND THIS ADDITIONAL RAINFALL
WILL RUNOFF MORE EASILY.
USED A BLEND OF THE HRRR AND THE RNK-WRFARW FOR POPS TONIGHT INTO
THURSDAY. AS THE COLD FRONT MOVES EAST ON THURSDAY TAPER OFF POPS
FROM THE NORTHWEST TO SOUTHEAST. A STRONGER THUNDERSTORM IS POSSIBLE
IN THE SOUTH AND SOUTHEAST ON THURSDAY WITH THE POTENTIAL OF HEAVY
RAIN.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
AS OF 345 PM EDT WEDNESDAY...
THURSDAY EVENING...SURFACE FRONT WILL BE WORKING ITS WAY ACROSS
THE PIEDMONT WITH MODELS TAKING THE FRONT TO THE SANDHILLS OF NC
BEFORE STALLING FRIDAY. NOT SURE HOW MUCH CLEARING WILL TAKE PLACE
BEHIND THE FRONT AS THE UPPER LEVEL FLOW BECOMES BLOCKY WITH THE
UPPER TROUGH ALSO STALLING ALOFT. AT THE VERY LEAST THINK DRYING
WILL TAKE PLACE IN THE LOWER AND MID LEVELS AS THE AS WINDS TURN
NORTHERLY...THEN NORTHEASTERLY AS SURFACE HIGH PRESSURE TRYS TO
WEDGE INTO THE AREA FROM THE NORTH. ATTM...WILL REMAIN OPTOMISTIC
AND KEEP FORECAST DRY FOR FRIDAY THROUGH AT LEAST THE FIRST HALF
OF THE WEEKEND. AT SOME POINT WINDS WILL VEER WITH SOUTHEASTERLY
FLOW BRINGING MOISTURE BACK INTO THE FORECAST.
WENT WITH THE COOLER MAV MOS WITH THE THINKING THAT MORE CLOUD
COVER AND A NORTHEASTERLY SURFACE WIND COMPONENT WILL KEEP THE
NUMBERS DOWN.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 345 PM EDT WEDNESDAY...
CAN`T SEEM TO SHAKE THE WET PATTERN.
MODEL GUIDANCE GENERALLY AGREES THE UPPER TROUGH ALONG THE EAST
COAST WILL BECOME STUCK...POSSIBLY CUTTING OFF AND RETROGRADING
NEXT WEEK. THIS WILL QUICKLY TURN THE LOW LEVEL FLOW...WITH WINDS
CHANNELLING DEEPER MOISTURE BACK INTO THE FORECAST AREA FAVORING
HIGHER POPS.
AS FOR TEMPS...DO NOT SEE ANY EXTREMES. 85H TEMPS HOVER AROUND
+16 DEG C FOR MOST OF THE WEEK. WITH A MIX OF SUN AND CLOUDS THIS
SHOULD YEILD HIGH TEMPS MAINLY IN THE 80S AND LOWS IN THE 60S.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 800 PM EDT WEDNESDAY...
BKN LINE OF MVFR/IFR SHOWERS AND THUNDERSTORMS WILL MOVE EAST
ACROSS THE REGION TONIGHT INTO THURSDAY...AS UPPER TROUGH DEEPENS
ACROSS THE GREAT LAKES REGION.
UNTIL THE UPPER TROUGH MOVES EAST OF THE AREA THURSDAY EVENING...
EXPECT WIDESPREAD MVFR WITH OCCASIONAL IFR CIGS PER VERY MOIST
BOUNDARY LAYER.
EXTENDED AVIATION DISCUSSION...
MODELS INITIALLY PUSH DEEP CONVECTION TO THE COASTAL AREAS FRIDAY
AND SATURDAY WITH SOME CLEARING OVER THE APPALACHIANS IN THE WAKE
OF THE UPPER LEVEL TROF. RETURN FLOW HOWEVER...IS EXPECTED TO
BRING THE THREAT OF SHOWERS BACK INTO THE FORECAST FOR EARLY NEXT
WEEK...POSSIBLY AS EARLY AS SUNDAY. UNTIL THE MOISTURE
RETURNS...SHOULD SEE VFR CONDITIONS FOR THE FIRST HALF OF THE
UPCOMING WEEKEND...ASIDE FROM EARLY MORNING IFR BR/FG.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLASH FLOOD WATCH UNTIL 2 AM EDT THURSDAY FOR VAZ007-009>020-
022>024-032.
NC...FLASH FLOOD WATCH UNTIL 2 AM EDT THURSDAY FOR NCZ001>003-018-
019.
WV...FLASH FLOOD WATCH UNTIL 2 AM EDT THURSDAY FOR WVZ042>045.
&&
$$
SYNOPSIS...RAB
NEAR TERM...KK/PM/RAB
SHORT TERM...PM
LONG TERM...PM
AVIATION...PM
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1121 PM PDT Mon Jul 8 2013
.SYNOPSIS...
A weather system passing through the Inland Northwest today will
promote scattered showers and thunderstorms across the northern
mountains of Washington and Idaho, as well as southeast
Washington. Tuesday and Wednesday will be the warmest days this
week with high temperatures in the upper 80s to mid 90s. Thursday
through Saturday will be occasionally breezy with temperatures
pretty close to average, or slightly below. Low shower and
thunderstorms chances will linger near the mountains, especially
closer to the Canadian border, but otherwise conditions will be
dry. Temperatures begin to warm up again slightly going into early
next week.
&&
.DISCUSSION...
This Afternoon and Evening: The weather over northeast Washington
and the Idaho Panhandle will be active. Scattered thunderstorms
are expected through early this evening. Our concern area extends
from the Okanogan Highlands through northeast Washington into the
northern and central Idaho Panhandle. The 2 PM visible imagery
shows a mid-level atmospheric circulation in far southeast British
Columbia slowly moving east. Around this circulation the
atmosphere has become increasingly unstable with the RUC analysis
indicating 500 to 1000 J/KG of surface based CAPE from Republic to
Sandpoint to Spokane to Kellogg. Very little convective inhibition
remains, so look for convection to continue to develop through
late afternoon. Shear and buoyancy values suggest the potential
for organized multi-cell thunderstorms. Our main threat through 6
PM will be the potential for hail, heavy rain, and gusty winds. A
couple severe thunderstorm warnings may be needed, but most of the
cells through early evening will probably pulse up, produce hail
up to dime size, then pulse down. The threat for thunderstorms
should dissipate quickly early this evening as the upper level
support (upper low in SE BC) moves east of the region focusing the
threat over Montana.
Tuesday: A shortwave ridge of high pressure will replace the
trough over the Inland Northwest for Tuesday. Look for relatively
light winds, clear skies and temperatures 5 to 8 degrees above
average. /GKoch
Tuesday night through Thursday evening...General long-wave trof
lingers overhead but the air-mass contained in it is not very
unstable and does not have much moisture tied to any discrete
feature traversing through it. As thus for the most part a dry
forecast remains, with exception being minimal chance for
afternoon/evening mountain thunderstorms up North and over the
Idaho Panhandle Thursday afternoon and evening. Forecast
temperatures remain just slightly on the warm side of what would
be considered normal for this time of year. Other shortwave
features of note will be a dry disturbance passage on Wednesday
afternoon and evening which will increase the wind some but only
to low breezy category at most. /Pelatti
Thursday night through Monday: The Inland Northwest remains in a
more active pattern through the week`s end, before high pressure
starts to nudge in Sunday and Monday. A shortwave system continues
to slip through Idaho into Montana Thursday night, even as a
second shortwave begins to move toward the Cascades. That second
shortwave slips across eastern Washington and north Idaho through
Friday, with a third wave slipping by Saturday before high
pressure begins to nudge in Saturday night. Models continue to
disagree over some of the details. Yet the progression of these
features will bring some shower and thunderstorm chances to the
region. The main chances remain around the northern mountains.
Smaller chances will be found across the Blue Mountains through
the Central Panhandle, including the Palouse as the wave is
exiting Thursday night. While some of these waves are depicted as
being somewhat dynamic/strong, models still do not depict
significant instability and keep the deeper moisture southeast of
the region. So regardless of timing and track, fuel for showers is
not impressive. Thus over PoPs remain slight or isolated in
nature. Look for occasional breezy conditions, especially Friday,
with the passage of these waves. Although a couple models skim
another wave by southern BC, near the WA/ID border early next
week, drier conditions are forecast going into Sunday and Monday.
Look for slightly cooler than normal conditions around the end of
the work week, before temperatures warm closer to or slightly
above seasonal norms going into early next week. /J. Cote`
&&
.AVIATION...
06Z TAFS: Periods of thin high clouds moving through overnight
otherwise VFR and light winds for the next 24 hrs.
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 58 89 60 89 59 83 / 0 0 0 0 0 10
Coeur d`Alene 56 87 58 87 58 83 / 10 0 0 0 0 10
Pullman 53 87 55 88 55 82 / 0 0 0 10 10 10
Lewiston 62 95 64 95 63 90 / 0 0 0 10 10 10
Colville 53 90 56 92 56 86 / 10 0 0 0 0 10
Sandpoint 50 85 53 86 54 82 / 20 0 0 0 0 10
Kellogg 54 87 57 87 58 82 / 10 0 0 0 10 10
Moses Lake 60 94 62 94 60 87 / 0 0 0 0 0 0
Wenatchee 64 92 65 91 62 85 / 0 0 0 0 0 0
Omak 60 94 60 92 59 86 / 0 0 0 0 0 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
716 PM CDT WED JUL 10 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 313 PM CDT WED JUL 10 2013
LATEST WATER VAPOR IMAGERY SHOWED NORTHWEST FLOW ALOFT OVER THE
REGION. AN EMBEDDED SHORTWAVE WAS NOTED OVER SOUTHERN
MANITOBA...HEADING SOUTHEAST. THIS WILL BE THE FEATURE TO KEEP A
CLOSE EYE ON LATE THIS AFTERNOON THROUGH THIS EVENING AS IT MOVES
ACROSS NORTHERN/CENTRAL WISCONSIN. ELSEWHERE ACROSS THE CONUS A
TROUGH STRETCHED FROM THE EASTERN ONTARIO SOUTH THROUGH THE OHIO
RIVER VALLEY. A RIDGE WAS NOTED OVER THE ROCKIES WITH ANOTHER
TROUGH LOCATED JUST OFF OF THE WEST COAST. SURFACE OBSERVATIONS
SHOWED HIGH PRESSURE OVER THE EASTERN DAKOTAS...EDGING EAST INTO
THE UPPER MISSISSIPPI RIVER VALLEY. THE HIGH WAS PROVIDING MOSTLY
TO PARTLY SUNNY SKIES THIS AFTERNOON ACROSS THE FORECAST AREA.
NORTHWEST WINDS ARE USHERING IN A MUCH MORE COMFORTABLE AIRMASS
WITH TEMPERATURE IN THE UPPER 70S TO LOWER 80S AND DEWPOINTS IN
THE UPPER 40S TO MIDDLE 50S.
THE SHORTWAVE TROUGH WILL MOVE ACROSS NORTHWEST WISCONSIN LATE THIS
AFTERNOON AND PUSH SOUTH INTO CENTRAL WISCONSIN DURING THE EVENING
HOURS. THE RAP AND NAM CONTINUE TO PRODUCE LIGHT PRECIPITATION
WITH THIS FEATURES. ALSO...THE UPPER LEVEL SUPPORT IS FAIRLY
HEALTHY WITH 500-300 MB POTENTIAL VORTICITY ADVECTION OF 12 TO 15
PVU/S. FORECAST SOUNDINGS OVER NORTH CENTRAL AND CENTRAL WISCONSIN
ARE RATHER DRY THIS AFTERNOON AND THIS EVENING AS HIGH PRESSURE
BUILDS IN AT THE SURFACE. GIVEN THE STRENGTH OF THE WAVE WOULD
EXPECTED TO AT LEAST GET A FEW SPRINKLES OR LIGHT SHOWERS ALONG
AND NORTHEAST OF THE INTERSTATE 94 CORRIDOR THIS EVENING...MAINLY
IN THE 8PM TO 2AM TIMEFRAME. SURFACE HIGH PRESSURE WILL DOMINATE
THE WEATHER PATTERN ACROSS THE FORECAST AREA ON THURSDAY PROVIDING
MOSTLY SUNNY SKIES AND HIGHS IN THE 79 TO 83 DEGREE RANGE. DEEP
MIXING DURING THE AFTERNOON HOURS WILL ALLOW DEWPOINTS TO FALL
INTO UPPER 40S TO LOWER 50S. HAVE LOWERED DEWPOINTS A FEW DEGREES
FROM PREVIOUS FORECAST. ALSO...WILL HAVE TO KEEP AN EYE ON AREAS
OF FOG IN THE MORNING IN VALLEY LOCATIONS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 313 PM CDT WED JUL 10 2013
THE SURFACE HIGH WILL BE CENTERED OVER THE WESTERN GREAT LAKES
THURSDAY NIGHT AS AN UPPER RIDGE BUILDS IN FROM THE NORTHERN
PLAINS WITH DRY AND QUIET WEATHER IS EXPECTED THURSDAY NIGHT INTO
FRIDAY. WARMER TEMPERATURES WILL START TO FILTER BACK INTO THE
REGION AS THE HIGH SLIDES OFF TO THE EAST AND LOW PRESSURE
DEVELOPS OVER THE PLAINS. THE BREEZY SOUTHERLY FLOW OVER THE
REGION ON FRIDAY WILL ALLOW DEEP MIXING AND TEMPERATURES TO CLIMB
INTO THE MID TO UPPER 80S UNDER MOSTLY SUNNY SKIES. THE RIDGE WILL
FLATTEN SATURDAY INTO SUNDAY AS NUMEROUS EMBEDDED SHORTWAVES IN
WEST/SOUTHWEST FLOW ALOFT TRACK ACROSS THE DAKOTAS THROUGH THE
NORTHERN HALF OF MINNESOTA INTO NORTHERN WISCONSIN. THE BULK OF
THE INSTABILITY REMAINS NORTH AND WEST OF THE FORECAST AREA. THERE
IS AN INTERESTING FEATURE ADVERTISED IN THE GEM AND ECMWF...A
RETROGRADING LOW MOVES WEST OUT OF THE CENTRAL APPALACHIANS SUNDAY
INTO MONDAY AND APPROACHES THE MIDDLE MISSISSIPPI RIVER VALLEY.
WILL HAVE TO KEEP A CLOSE WATCH ON THIS FEATURE LATE IN THE
WEEKEND GOING INTO EARLY NEXT WEEK IF IT DOES MATERIALIZE.
OTHERWISE...THE UPPER RIDGE ATTEMPTS TO ANCHOR OVER THE THE
CENTRAL CONUS...STRETCHING INTO THE UPPER MISSISSIPPI RIVER
VALLEY. ZONAL FLOW ALOFT...WITH EMBEDDED SHORTWAVES...OVER THE
DAKOTAS THROUGH THE WESTERN GREAT LAKES WILL BRING PERIODIC
CHANCES FOR SHOWERS AND THUNDERSTORMS. THE BULK OF THE ACTIVITY
SHOULD OCCUR NORTH OF INTERSTATE 90 LATE THIS WEEKEND GOING INTO
THE MIDDLE OF NEXT WEEK. WITH THE WARM SOUTHERLY FLOW OVER THE
AREA AND MUCH OF THE CONVECTIVE ACTIVITY PASSING JUST TO THE NORTH
OF THE AREA...DECIDED TO WARM HIGH TEMPERATURES 1 TO 2 DEGREES
OVER A CONSENSUS MODEL BLEND...PRODUCING HIGHS IN THE UPPER 80S TO
AROUND 90
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 715 PM CDT WED JUL 10 2013
VFR CONDITIONS EXPECTED THROUGH AT LEAST FRIDAY.
OVERNIGHT...WILL BE MONITORING THE COOLING RATE OF TEMPERATURES
FOR POSSIBLE MISSISSIPPI RIVER VALLEY FOG /KLSE ONLY/. THE AIR
MASS SETTLING IN IS FAIRLY DRY BUT WITH SOME LIGHTER WINDS IN THE
LOWEST FEW THOUSAND FEET AND CLEAR SKIES EXPECTED...WILL MONITOR. TIME OF
YEAR...DEPTH OF THE LIGHT WINDS...AND A GOOD WARM DRYING DAY WITH
DEEPER MIXING TODAY WILL WORK AGAINST THE FOG FORMATION. I WOULD
ESTIMATE A 5-10 PERCENT PROBABILITY OF IFR AT KLSE AROUND SUNRISE
AT THIS TIME.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...BAUMGARDT
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
451 PM CDT TUE JUL 9 2013
.MESOSCALE DISCUSSION...
ISSUED AT 451 PM CDT TUE JUL 9 2013
DESPITE DECENT RECOVERY IN TEMPERATURES AFTER THE PASSAGE OF THE
MORNING/MIDDAY CONVECTION...SUCH AS LA CROSSE CLIMBING UP TO 90F
WITH A DEWPOINT OF 72F...CONVECTION IS DEFINITELY STRUGGLING. TWO
THINGS ARE GOING ON HERE...
1. MASSIVE DRYING SEEN ON WATER VAPOR IN THE WAKE OF THE
MORNING/MIDDAY CONVECTION AND ASSOCIATED MCV/SHORTWAVE TROUGH.
THIS DRYING IMPLIES SUBSIDENCE.
2. A SURGE OF WARMER AIR AT 750MB ACCOMPANYING THE MASSIVE DRYING.
THIS IS SEEN NICELY ON 20Z TAMDAR SOUNDINGS AT MPX AND DMX WHICH
ARE 14C AND 16C RESPECTIVELY. THE LOWER TEMPERATURES AT MPX HAVE
ALLOWED SOME CONVECTION TO FIRE NORTH OF LA
CROSSE...HOWEVER...OVERALL THESE VALUES ARE PUTTING A CAP TO
CONVECTION. MODIFYING A RAP SOUNDING AT 22Z FOR LA CROSSE WITH THE
CURRENT SURFACE TEMP/DEWPOINTS AND A 16C 750MB TEMP STILL SHOWS A
LITTLE CAPPING TO OVERCOME.
ANTICIPATING LITTLE CHANGE IN CONVECTIVE ACTIVITY THROUGH THE NEXT
COUPLE HOURS AS WE STAY IN THE SUBSIDENCE/DRYING ALOFT AND WARM
750MB AIR SPREADS EAST. ADDITIONALLY...WE WILL BE APPROACHING THE
END OF HEATING SHORTLY...WHICH IN TURN WILL ONLY INCREASE THE CIN
HEADING THROUGH THE EVENING.
&&
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY)
ISSUED AT 250 PM CDT TUE JUL 9 2013
AN UPPER LEVEL SHORTWAVE TROUGH WAS TRACKING EAST ACROSS THE
NORTHERN PLAINS THIS AFTERNOON...AND WILL WORK ACROSS NORTHERN PARTS
OF THE REGION THIS EVENING. AHEAD OF THE UPPER LEVEL ENERGY AND AT
THE SFC...AN ASSOCIATED FRONTAL BOUNDARY IS PROGGED TO MOVE OVER THE
LOCAL FORECAST AREA BY 00Z...EXITING INTO EASTERN WI AFTER 06Z.
MORNING/EARLY AFTERNOON CONVECTION HAS WORKED OVER THE ATMOSPHERE
PRETTY GOOD...AND NOT A LOT OF TIME/SPACE TO RE-ESTABLISH SOME
INSTABILTY AHEAD OF THE FRONT. MESO MODELS NOT BULLISH ON FIRING
MUCH/IF ANY CONVECTION ALONG THE SFC BOUNDARY AS IT SWEEPS THROUGH
THIS EVENING. THINK THIS IS THE WAY TO GO. THE CAVEAT...OF
COURSE...IS IF THE ATMOSPHERE CAN JUICE BACK UP...THE STORM CHANCES
WOULD INCREASE...AND THERE COULD BE A STRONG/SEVERE RISK. LATEST
RADAR IMAGERY HAS SHOWN SOME DEVELOPMENT OVER NORTHWEST
WI...ASSOCIATED WITH AN MCV FROM THE MORNING CONVECTION. NOT MUCH
ELSEWHERE...ALTHOUGH SOME AGGRAVATED CU PER SATELLITE IMAGERY COULD
EVENTUALLY BECOME SHOWERS/STORMS. WILL MONITOR TRENDS...BUT WILL
STEER THE FORECAST FOR LESS PCPN CHANCES.
HIGH PRESSURE STARTS TO BUILD IN FROM THE NORTHERN PLAINS ON
WED...CLEARING OUT THE SKIES AND USHERING IN A MUCH COOLER AND DRIER
AIRMASS.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 250 PM CDT TUE JUL 9 2013
HIGH PRESSURE WILL BE THE MAIN WEATHER FEATURE FOR THE REGION INTO
FRIDAY...WITH RELATIVELY COOLER/LESS HUMID AIR FOR THE REST OF THE
WORK WEEK.
UPPER LEVEL SHORTWAVE TROUGH WILL DRIVE EASTWARD ACROSS SOUTHERN
CANADA FOR THE UPCOMING WEEKEND. WHILE THE BULK OF THE UPPER LEVEL
ENERGY WILL HOLD WELL NORTH OF THE LOCAL AREA...THIS SYSTEM WILL
DRAG A SFC FRONT ACROSS THE UPPER MISSISSIPPI RIVER VALLEY FRI
NIGHT/SAT. THE GFS/ECMWF LAYS UP THE FRONT FROM WEST TO EAST AND
HANGS IT ACROSS THE REGION INTO THE EARLY PART OF NEXT WEEK. GOOD
LOW LEVEL MOISTURE RETURN INTO THE BOUNDARY WILL HELP FUEL
SHOWERS/STORMS...WITH SOME INSTABILITY TO POWER STORMS. WIND SHEAR
AT THIS TIME LOOKS MORE NORTH OF THE FRONT. THIS SCENARIO COULD
BRING HEAVY RAINS TO PARTS OF THE REGION...WITH TRAINING STORMS AND
A GOOD TAP INTO MOISTURE. THAT SAID...THERE IS UNCERTAINTY WITH
WHERE THE FRONT WILL REST AND IF IT WAVERS NORTH-SOUTH. WILL STICK
WITH A CONSENSUS/EC BLEND FOR THE RAIN CHANCES...FAVORING RAIN
CHANCES TO THE NORTH.
&&
.AVIATION...THROUGH 18Z WEDNESDAY
108 PM CDT TUE JUL 9 2013
PRIMARY CONCERN FOR AVIATION IS THE RISK FOR ANY NEW CONVECTION
LATE THIS AFTERNOON OR EARLY EVENING. WIND SHIFT WITH THE FRONTAL
PASSAGE AND ALSO THE POTENTIAL FOR MVFR CEILINGS ALSO OF NOTE.
FIRST ROUND OF CONVECTION HAS PUSHED EAST OF THE TAF SITES...BUT
THE COLD FRONT HAS NOT YET PASSED. A LINE OF CUMULUS DENOTES ITS
POSITION ACROSS SOUTH-CENTRAL MN AS OF 18Z. STILL A RISK FOR SOME
CONVECTION WITH INCREASING INSTABILITY WITH AFTERNOON HEATING AND
ASSISTANCE FROM UPPER LEVEL SHORT WAVE TROUGH MOVING ACROSS MN.
BUT WIND SHEAR AND CONVERGENCE INTO THE FRONT NOT IDEAL. STILL
KEPT A SMALL RISK IN THE FORECAST. ALSO SEE SOME POST FRONTAL MVFR
CEILINGS ON SATELLITE...AND THIS COULD IMPACT THE TAF SITES FOR A
TIME. CLEARING OVERNIGHT HOWEVER WITH VFR CONDITIONS ANTICIPATED
TO PREVAIL INTO WEDNESDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
MESOSCALE...AJ
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION.....MW
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
113 PM CDT TUE JUL 9 2013
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 315 AM CDT TUE JUL 9 2013
MAIN CONCERN WILL BE TRACK OF PLAINS THUNDERSTORM COMPLEX THIS
MORNING/TODAY...THEN SEVERE POTENTIAL GOING THIS AFTERNOON.
LOOP OF WATER VAPOR IMAGERY THIS MORNING ALONG WITH RAP 500MB
ANALYSIS SHOWS A FAIRLY VIGOROUS MID-LEVEL TROUGH MOVING OUT OF MT
INTO THE DAKOTAS...WHILE ANOTHER WEAKER WAVE WAS NOTED ACROSS
CENTRAL NEB. 925-850MB MOISTURE TRANSPORT AHEAD OF THESE WAVES WAS
PRODUCING A BROKEN LINE COMPLEX OF THUNDERSTORMS EXTENDING FROM
EASTERN ND/SD...INTO EASTERN NEB. THIS COMPLEX OF STORMS WAS MOVING
EAST AT 30-35KT...MAKING INROADS TOWARD THE AREA. SIMPLE
EXTRAPOLATION BRINGS THIS COMPLEX INTO SOUTHEAST MN/NORTHEAST IA
AROUND 12Z/7AM-ISH.
ARX/HRRR/NMM WRF MODELS DID A PRETTY GOOD JOB INITIALIZING THIS
CONVECTION AND REMAIN IN FAIRLY DECENT AGREEMENT THROUGH THE DAY
TODAY. HAVE TRENDED THE FORECAST TO MATCH UP WITH A BLEND OF THESE
SOLUTIONS. APPEARS THE COMPLEX OF STORMS WILL MAINTAIN
ITSELF...COMING ACROSS THE AREA THIS MORNING AS 925-850MB MOISTURE
TRANSPORT INCREASES/NOSES INTO THE REGION. THIS COMPLEX OF STORMS
HAS A HISTORY OF 30-50KT WINDS ASSOCIATED WITH IT OVER SD.
SO...CANNOT RULE OUT SOME BORDERLINE SEVERE WINDS AS IT ROLLS INTO
OUR AREA. COULD BE INTERESTING GOING INTO THIS AFTERNOON AS THE WRF
MODELS SHOW THIS COMPLEX DEVELOPING A FAIRLY SIGNIFICANT MCV
STRUCTURE. THIS IN TURN HAS THE POTENTIAL OF PRODUCING A
MINI-OUTFLOW/COLD FRONT ON ITS SOUTHWEST FLANK IN THE 18-21Z TIME
FRAME. WITH AMPING SHEAR IN THE 30-40KT RANGE DUE TO THE MCV AND
MORE THAN AMPLE CAPE IN THE 4000-5500J/KG RANGE...LOOKING FOR THE
POSSIBILITY OF A LINE OF SEVERE STORMS WITH DAMAGING WINDS DEVELOPING
ACROSS CENTRAL/SOUTHWEST WI THIS AFTERNOON. THIS OF COURSE WILL ALL
DEPEND ON HOW MUCH CLOUD IS PRESENT WHICH COULD AFFECT THE AMOUNT OF
AVAILABLE INSTABILITY REALIZED. THE POTENTIAL IS DEFINITELY THERE AND
WILL HAVE TO BE WATCHED CLOSELY. ANOTHER THING TO WATCH IS HEAVY
RAINFALL POTENTIAL WITH MUGGY AIRMASS IN PLACE AND PRECIPITABLE WATER
IN THE 2-2.25 INCH RANGE. THIS COULD AID IN TORRENTIAL DOWNPOURS OUT
OF THE STORMS AND SOME LOCALIZED PONDING OF WATER IN POOR DRAINAGE
AREAS.
LOOKING FOR THE MAIN COLD FRONT TO THEN SLIDE SOUTHEAST ACROSS THE
AREA IN THE 00-06Z TIME FRAME. UNCERTAIN ON HOW THIS IS GOING TO
PLAY OUT WITH THE POTENTIAL FOR SEVERE STORMS ALREADY GOING THROUGH
THE AREA THIS AFTERNOON. ATMOSPHERE COULD BE FAIRLY STABILIZED
BEHIND THIS CONVECTION AND COLD FRONT COULD SLIP THROUGH WITH NO
CONVECTION. APPEARS HIGHEST POTENTIAL FOR EVENING CONVECTION MAY BE
ALONG AND NORTH OF I-94 WHERE BETTER 500-300MB PV-ADVECTION WILL
EXIST. EXPECTING COLD FRONT AND ASSOCIATED CONVECTION TO PUSH EAST OF
THE AREA AROUND DAYBREAK AS HIGH PRESSURE BUILDS IN FROM THE
DAKOTAS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 315 AM CDT TUE JUL 9 2013
HIGH PRESSURE WILL PRODUCE VERY PLEASANT WEATHER CONDITIONS ACROSS
THE AREA WEDNESDAY AND THURSDAY. LOOK FOR HIGHS IN THE 75-80 DEGREE
RANGE ON WEDNESDAY AND UPPER 70S/LOWER 80S ON THURSDAY. MUCH LOWER
HUMIDITY LEVELS WILL ALSO BE NOTED AS DEWPOINTS HOVER IN THE 50S.
PLAN ON WARMER TEMPERATURES ON FRIDAY ALONG WITH INCREASING HUMIDITY
LEVEL AS THE HIGH SLIDES OFF TO THE EAST AND SOUTH WINDS SET UP
ACROSS THE AREA. LOOK FOR HIGHS IN THE 80S WITH A FEW READINGS
FLIRTING WITH THE 90 DEGREE MARK ACROSS SOUTHEAST MN.
EC/GFS ACTUALLY IN PRETTY GOOD AGREEMENT GOING INTO THE WEEKEND.
BOTH MOVE A COLD FRONT INTO THE UPPER MISSISSIPPI RIVER REGION BY
SUNDAY MORNING...THEN HANG IT UP ACROSS WI INTO CENTRAL IA BY
MONDAY. THIS WILL PRODUCE A CHANCE OF SHOWERS AND THUNDERSTORMS FROM
FRIDAY NIGHT STRAIGHT THROUGH MONDAY. OTHERWISE...LOOK FOR
TEMPERATURES TO BE RIGHT AROUND NORMAL LEVELS IN THE 80S.
&&
.AVIATION...THROUGH 18Z WEDNESDAY
108 PM CDT TUE JUL 9 2013
PRIMARY CONCERN FOR AVIATION IS THE RISK FOR ANY NEW CONVECTION
LATE THIS AFTERNOON OR EARLY EVENING. WIND SHIFT WITH THE FRONTAL
PASSAGE AND ALSO THE POTENTIAL FOR MVFR CEILINGS ALSO OF NOTE.
FIRST ROUND OF CONVECTION HAS PUSHED EAST OF THE TAF SITES...BUT
THE COLD FRONT HAS NOT YET PASSED. A LINE OF CUMULUS DENOTES ITS
POSITION ACROSS SOUTH-CENTRAL MN AS OF 18Z. STILL A RISK FOR SOME
CONVECTION WITH INCREASING INSTABILITY WITH AFTERNOON HEATING AND
ASSISTANCE FROM UPPER LEVEL SHORT WAVE TROUGH MOVING ACROSS MN.
BUT WIND SHEAR AND CONVERGENCE INTO THE FRONT NOT IDEAL. STILL
KEPT A SMALL RISK IN THE FORECAST. ALSO SEE SOME POST FRONTAL MVFR
CEILINGS ON SATELLITE...AND THIS COULD IMPACT THE TAF SITES FOR A
TIME. CLEARING OVERNIGHT HOWEVER WITH VFR CONDITIONS ANTICIPATED
TO PREVAIL INTO WEDNESDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...MW
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1206 PM CDT TUE JUL 9 2013
.UPDATE...HIGHS AND WX/POPS UPDATED IN THE TODAY PERIOD FOR THE
LATEST TRENDS. MORE SKY COVER THAN PREVIOUSLY EXPECTED...AND NOT
ANTICIPATING MUCH IN IMPROVEMENT. AS SUCH...WITH INSOLATION NOT
BEING AS FAVORABLE...COINCIDING WITH A MCS AND TRAILING STRATIFORM
REGION MOVING THROUGH THE CWA...HIGHS WERE DECREASED 3-4 DEGREES.
THE WX AND POPS IN THE NEAR-TERM WERE UPDATED TO REFLECT THE LEADING
EDGE AND ITS MOVEMENT EAST.
OTHERWISE...REMOVED WORDING OF HEAVY RAIN AND TRW+ THIS LATE
AFTERNOON/EVENING. THE POTENTIAL FOR STRONGER THUNDERSTORMS
DEVELOPING LATE THIS AFTERNOON IS LESSENING. LATEST MESOSCALE
MODELS DONT SHOW MUCH IN REDEVELOPMENT THIS AFTERNOON/EVENING
BESIDES THIS LINE. OF WHICH...THE NEAR-STORM ENVIRONMENT IN WHICH
THE LINE IS MOVING THROUGH IS NOT THAT FAVORABLE FOR SEVERE
WEATHER. A FEW STRONG STORMS THOUGH ARE POSSIBLE. CURRENT THINKING
IS THAT THE ADDITIONAL SKY COVER WILL LIMIT DESTABILIZATION FOR
ACTIVITY LATER ON. SITUATION STILL WARRANTS BEING WATCHED GIVEN
THE RAP STILL SHOWS DECENT POTENTIAL INSTABILITY LATE THIS
AFTERNOON/EVENING AND ON...THOUGH IT LIKELY WONT BE AS ROBUST AS
PROGGED.
&&
.AVIATION/18Z TAFS/...MAIN CONCERN IS LINE OF SHOWERS AND
THUNDERSTORMS TRAVERSING THE CWA WEST TO EAST. AS SEEN FROM
RADAR...LEADING EDGE OF SHOWERS AND THUNDERSTORMS IS CURRENTLY
ALONG A LINE FROM REESEVILLE TO FORT ATKINSON TO JUST WEST OF
JOHNSTOWN CENTER WITH A TRAILING REGION OF STRATIFORM RAIN BEHIND
IT. CIGS AND VISIBILITY ASSOCIATED WITH THESE THUNDERSTORMS ARE
PREDOMINANTLY RIGHT AT OR ABOVE MVFR THRESHOLDS.
LEADING EDGE IS EXPECTED TO REACH KUES AND KMKE BETWEEN 17 AND 18
UTC. AHEAD OF THE LINE IS A LOW STRATUS DECK WITH CIGS AROUND
800-1200 FT...THAT ARE PRESENT AT KMKE...KUES...AND KENW
CURRENTLY. THIS SHOULD GIVE WAY ONCE THE LINE MOVES THROUGH. AFTER
THE THUNDERSTORMS AND SHOWERS MOVE THOUGH...CHANCE FOR MORE
ACTIVITY STILL EXISTS LATER ON. HOWEVER...THE POTENTIAL FOR MORE
SHOWERS AND THUNDERSTORMS IS DECREASING DUE TO INCREASING CLOUD
COVER THAN WHAT WAS PREVIOUSLY EXPECTED. THIS WILL HELP LIMIT THE
CONVECTIVE POTENTIAL LATE THIS AFTERNOON/EVENING. THIS IS FURTHER
SUPPORTED BY MESOSCALE MODELS...AS THEY DO NOT SHOW MUCH IN TERMS
OF DEVELOPMENT LATER ON AFTER THIS LINE PASSES THROUGH.
&&
.PREV DISCUSSION... /ISSUED 335 AM CDT TUE JUL 9 2013/
SHORT TERM...
TODAY AND TONIGHT - CONFIDENCE...MEDIUM
LIGHT BOUNDARY LAYER WINDS AND RECENT RAINFALL HAS RESULTED IN AREAS
OF DENSE FOG OVER THE SHEBOYGAN AREA. CALLS TO NEIGHBORING COUNTY
REVEAL AREAS OF DENSE FOG AS WELL. WITH LITTLE CHANGE EXPECTED
THROUGH THE EARLY MORNING...POSTED DENSE FOG ADVY FOR FOUR NORTHEAST
COUNTIES UNTIL 14Z. LIGHT ONSHORE WINDS MAY CAUSE DENSE FOG TO
PERSIST UNTIL LATE MORNING IN THE SHEBOYGAN AREA.
OTHERWISE PATCHY FOG WILL CONTINUE ELSEWHERE THROUGH THE EARLY
MORNING DUE TO THE LIGHT WINDS. APPEARS BRIEF PERIOD OF SHORT WAVE
RIDGING AND SLOWER LOW LEVEL JET WILL RESULT IN DRY CONDITIONS MOST
AREAS TO START THE DAY. HOWEVER WITH WEAK FRONTAL BOUNDARY
MEANDERING IN THE AREA...AND LOW LEVEL INSTABILITY...POSSIBLE AN
ISOLATED THUNDERSTORM COULD DEVELOP THROUGH THE EARLY MORNING.
LEANING TOWARD TWO PERIODS OF CONVECTION AFFECTING SOUTHERN WI FROM
LATE MORNING IN THE WEST INTO THE EVENING.
FORCING FROM UPSTREAM SHORT WAVE TROUGH OVER EASTERN DAKOTAS AND
NEBRASKA WILL JOIN FORCES WITH PIVOTING WEAKER LOW LEVEL JET IN
BRINGING SCATTERED T TO WESTERN CWA BY LATE MORNING...WITH SOME OF
THIS ACTIVITY LIKELY HOLDING TOGETHER AS IT MOVES INTO EASTERN CWA
THIS AFTERNOON. BELIEVE THERE WILL BE ENOUGH TIME FOR ATMOSPHERE TO
DESTABILIZE AHEAD OF APPROACHING COLD FRONT LATE THIS AFTERNOON AND
EVENING. ENHANCED FORCING FROM RIGHT ENTRANCE REGION SHOULD RESULT
IN NUMEROUS CONVECTION ACROSS SRN WI. BULK SHEAR INCREASES FAVORING
MULTICELLS WITH SOME SUPERCELLS BY THE EVENING. HEAVY RAINFALL ALSO
POSSIBLE THIS EVENING WITH WARM CLOUD DEPTH EXCEEDING 10K FEET AND
MBE VELOCITY FALLING TO LESS THAN 10KTS FOR A PERIOD OF TIME DURING
THE STRONGEST FORCING. WILL HOLD OFF ON FLASH FLOOD WATCH AS ONE
HOUR COUNTY RAINFALL FLASH FLOOD GUIDANCE AROUND 2.0 MOST AREAS.
WILL HOWEVER ISSUE ESF FOR POTENTIAL. DECREASING CONVECTION TREND
OVERNIGHT AS COLD FRONT EXITS SOUTHEAST LATE AND UPPER LEVEL JET
PIVOTS EAST.
WEDNESDAY...FORECAST CONFIDENCE HIGH.
THE SURFACE COLD FRONT ASSOCIATED WITH AN UPPER LEVEL TROUGH MOVING
SOUTHEAST THROUGH WISCONSIN WILL CLEAR FAR SOUTHEAST WI BY MID WED
MORNING. ANY SHOWERS OR STORMS LINGERING ALONG THIS FRONT WILL CLEAR
OUT WITH THE FRONTAL PASSAGE. DRIER AIR WILL MOVE INTO SOUTHERN WI
BEHIND THIS FRONT.
NORTHWEST WINDS WILL INCREASE DURING THE DAY AS HIGH PRESSURE BUILDS
INTO THE MIDWEST.
THURSDAY THROUGH FRIDAY...FORECAST CONFIDENCE HIGH.
HIGH PRESSURE WILL SLOWLY DRIFT ACROSS THE GREAT LAKES REGION. LIGHT
WINDS WILL LEAD TO A LAKE BREEZE EACH DAY. SO WHILE INLAND TEMPS
WILL BE 80 TO 83...MAX LAKESHORE TEMPS WILL BE IN THE MID/UPPER 70S.
LONG TERM...
SATURDAY AND BEYOND...FORECAST CONFIDENCE MEDIUM.
RETURN FLOW AROUND THE HIGH WILL BRING INCREASING HEAT AND HUMIDITY
BACK INTO SOUTHERN WISCONSIN FOR THE WEEKEND. THE CONSENSUS BLEND OF
MODELS SEEMS TO BE UNDERDOING THE MAX TEMP FORECAST FOR SAT/SUN
PERIOD...SO ADJUSTED THAT UP A BIT TOWARD MOS GUIDANCE VALUES. 925MB
TEMPS AROUND 21-22C SUGGEST HIGHS IN THE LOWER 80S. DEWPOINTS ARE
EXPECTED TO BE IN THE MID/UPPER 60S.
MODELS ARE SUGGESTING THAT THE EFFECTIVE BOUNDARY TO TRIGGER
THUNDERSTORMS WILL BE LINED UP ACROSS NORTHERN WI WITH THE UPPER JET
SITUATED ALONG THE US/CANADIAN BORDER. THIS MEANS THAT CHANCES FOR
ANY PRECIP IN SOUTHERN WI WILL NOT RETURN UNTIL MONDAY NEXT WEEK OR
EVEN LATER IF/WHEN THAT FRONTAL BOUNDARY SLIPS SOUTHWARD.
IF WE DO NOT GET PRECIP ALONG THAT FRONT MONDAY...WE WILL BE SHUT
OFF FROM RAIN UNTIL LATER IN THE WEEK DUE TO SPRAWLING HIGH PRESSURE
OVER THE CENTER OF THE COUNTRY.
AVIATION/12Z TAFS/...FOG FORMATION PREFERRED OVER STRATUS DUE TO
LIGHT BOUNDARY LAYER WINDS...HOWEVER MAY BE A BRIEF PERIOD OF MVFR
CIGS OR LOWER EARLY THIS MORNING. VSBYS ASSOCD WITH FOG EXPECTED TO
DROP TO MVFR OR POSSIBLY LOWER FOR SEVERAL HOURS AS WELL.
OTRW...SCATTERED CONVECTION EXPECTED TO FIRE THIS AFTERNOON WITH A
SECOND WAVE LIKELY THIS EVENING. CIGS ASSOCD WITH THUNDER LIKELY TO
FLIRT WITH MVFR LEVELS.
MARINE...LIGHT WINDS IN THE SURFACE RIDGE OVER LAKE MICHIGAN AND
HIGH LOW LEVEL MOISTURE HAS RESULTED IN DENSE FOG DEVELOPING OVER
CENTRAL AND NORTHERN LAKE MICHIGAN OVERNIGHT. LOCAL WEB CAMS SHOW
THE DENSE FOG OVER SHEBOYGAN HARBOR...AND 11-3.9 MICRON IMAGERY
SHOWS A SLOW SOUTHWARD DRIFT OF THE STRATUS/FOG AREA. WL POST DENSE
FOG ADVY FOR NORTHERN ZONES THROUGH THE MORNING...AND MAY HAVE TO
ADD SOUTHERN ZONES IF SOUTHWARD DRIFT CONTINUES. LOW LEVEL WINDS
REMAIN LIGHT THROUGH THE MORNING...THEN BEGIN TO PICK UP FROM THE
SOUTH AHEAD OF APPROACHING COLD FRONT. AREAS OF DENSE FOG MAY
PERSIST UNTIL COLD FRONT AND CONVECTION SPREADS IN LATER TODAY OR
TONIGHT...PROMPTING EXTENSION OF DENSE FOG ADVY. SEVERAL PERIODS OF
CONVECTION EXPECTED OVER NEARSHORE WATERS THIS AFTERNOON AND
TONIGHT. BEST CHANCE FOR A PERIOD OF STRONGER WINDS AND LARGE HAIL
LATE AFTERNOON THRU THE MID-EVENING.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...DENSE FOG ADVISORY UNTIL NOON CDT TODAY FOR WIZ052.
LM...DENSE FOG ADVISORY UNTIL NOON CDT TODAY FOR LMZ643-644.
&&
$$
UPDATE...ET
TODAY/TONIGHT AND AVIATION/MARINE...MBK
WEDNESDAY THROUGH MONDAY...MRC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
612 AM CDT TUE JUL 9 2013
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 315 AM CDT TUE JUL 9 2013
MAIN CONCERN WILL BE TRACK OF PLAINS THUNDERSTORM COMPLEX THIS
MORNING/TODAY...THEN SEVERE POTENTIAL GOING THIS AFTERNOON.
LOOP OF WATER VAPOR IMAGERY THIS MORNING ALONG WITH RAP 500MB
ANALYSIS SHOWS A FAIRLY VIGOROUS MID-LEVEL TROUGH MOVING OUT OF MT
INTO THE DAKOTAS...WHILE ANOTHER WEAKER WAVE WAS NOTED ACROSS
CENTRAL NEB. 925-850MB MOISTURE TRANSPORT AHEAD OF THESE WAVES WAS
PRODUCING A BROKEN LINE COMPLEX OF THUNDERSTORMS EXTENDING FROM
EASTERN ND/SD...INTO EASTERN NEB. THIS COMPLEX OF STORMS WAS MOVING
EAST AT 30-35KT...MAKING INROADS TOWARD THE AREA. SIMPLE
EXTRAPOLATION BRINGS THIS COMPLEX INTO SOUTHEAST MN/NORTHEAST IA
AROUND 12Z/7AM-ISH.
ARX/HRRR/NMM WRF MODELS DID A PRETTY GOOD JOB INITIALIZING THIS
CONVECTION AND REMAIN IN FAIRLY DECENT AGREEMENT THROUGH THE DAY
TODAY. HAVE TRENDED THE FORECAST TO MATCH UP WITH A BLEND OF THESE
SOLUTIONS. APPEARS THE COMPLEX OF STORMS WILL MAINTAIN
ITSELF...COMING ACROSS THE AREA THIS MORNING AS 925-850MB MOISTURE
TRANSPORT INCREASES/NOSES INTO THE REGION. THIS COMPLEX OF STORMS
HAS A HISTORY OF 30-50KT WINDS ASSOCIATED WITH IT OVER SD.
SO...CANNOT RULE OUT SOME BORDERLINE SEVERE WINDS AS IT ROLLS INTO
OUR AREA. COULD BE INTERESTING GOING INTO THIS AFTERNOON AS THE WRF
MODELS SHOW THIS COMPLEX DEVELOPING A FAIRLY SIGNIFICANT MCV
STRUCTURE. THIS IN TURN HAS THE POTENTIAL OF PRODUCING A
MINI-OUTFLOW/COLD FRONT ON ITS SOUTHWEST FLANK IN THE 18-21Z TIME
FRAME. WITH AMPING SHEAR IN THE 30-40KT RANGE DUE TO THE MCV AND
MORE THAN AMPLE CAPE IN THE 4000-5500J/KG RANGE...LOOKING FOR THE
POSSIBILITY OF A LINE OF SEVERE STORMS WITH DAMAGING WINDS DEVELOPING
ACROSS CENTRAL/SOUTHWEST WI THIS AFTERNOON. THIS OF COURSE WILL ALL
DEPEND ON HOW MUCH CLOUD IS PRESENT WHICH COULD AFFECT THE AMOUNT OF
AVAILABLE INSTABILITY REALIZED. THE POTENTIAL IS DEFINITELY THERE AND
WILL HAVE TO BE WATCHED CLOSELY. ANOTHER THING TO WATCH IS HEAVY
RAINFALL POTENTIAL WITH MUGGY AIRMASS IN PLACE AND PRECIPITABLE WATER
IN THE 2-2.25 INCH RANGE. THIS COULD AID IN TORRENTIAL DOWNPOURS OUT
OF THE STORMS AND SOME LOCALIZED PONDING OF WATER IN POOR DRAINAGE
AREAS.
LOOKING FOR THE MAIN COLD FRONT TO THEN SLIDE SOUTHEAST ACROSS THE
AREA IN THE 00-06Z TIME FRAME. UNCERTAIN ON HOW THIS IS GOING TO
PLAY OUT WITH THE POTENTIAL FOR SEVERE STORMS ALREADY GOING THROUGH
THE AREA THIS AFTERNOON. ATMOSPHERE COULD BE FAIRLY STABILIZED
BEHIND THIS CONVECTION AND COLD FRONT COULD SLIP THROUGH WITH NO
CONVECTION. APPEARS HIGHEST POTENTIAL FOR EVENING CONVECTION MAY BE
ALONG AND NORTH OF I-94 WHERE BETTER 500-300MB PV-ADVECTION WILL
EXIST. EXPECTING COLD FRONT AND ASSOCIATED CONVECTION TO PUSH EAST OF
THE AREA AROUND DAYBREAK AS HIGH PRESSURE BUILDS IN FROM THE
DAKOTAS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 315 AM CDT TUE JUL 9 2013
HIGH PRESSURE WILL PRODUCE VERY PLEASANT WEATHER CONDITIONS ACROSS
THE AREA WEDNESDAY AND THURSDAY. LOOK FOR HIGHS IN THE 75-80 DEGREE
RANGE ON WEDNESDAY AND UPPER 70S/LOWER 80S ON THURSDAY. MUCH LOWER
HUMIDITY LEVELS WILL ALSO BE NOTED AS DEWPOINTS HOVER IN THE 50S.
PLAN ON WARMER TEMPERATURES ON FRIDAY ALONG WITH INCREASING HUMIDITY
LEVEL AS THE HIGH SLIDES OFF TO THE EAST AND SOUTH WINDS SET UP
ACROSS THE AREA. LOOK FOR HIGHS IN THE 80S WITH A FEW READINGS
FLIRTING WITH THE 90 DEGREE MARK ACROSS SOUTHEAST MN.
EC/GFS ACTUALLY IN PRETTY GOOD AGREEMENT GOING INTO THE WEEKEND.
BOTH MOVE A COLD FRONT INTO THE UPPER MISSISSIPPI RIVER REGION BY
SUNDAY MORNING...THEN HANG IT UP ACROSS WI INTO CENTRAL IA BY
MONDAY. THIS WILL PRODUCE A CHANCE OF SHOWERS AND THUNDERSTORMS FROM
FRIDAY NIGHT STRAIGHT THROUGH MONDAY. OTHERWISE...LOOK FOR
TEMPERATURES TO BE RIGHT AROUND NORMAL LEVELS IN THE 80S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 611 AM CDT TUE JUL 9 2013
TWO COMPLEXES OF STORMS HEADED TOWARD THE AREA THIS MORNING. THE
FIRST IS MOVING NORTHEAST OUT OF NORTHERN IOWA AND SHOULD BEGIN TO
IMPACT KRST RIGHT AROUND 12Z AND THEN GET INTO KLSE NEAR 14Z.
BRIEF HEAVY RAINS ARE OCCURRING WITH THESE STORMS WITH THE
POTENTIAL TO DROP THE VISIBILITY TO IFR FOR A WHILE WITH MVFR
CEILINGS. THE NEXT COMPLEX IS MOVING QUICKLY EAST ACROSS MINNESOTA
AND LOOKS LIKE IT SHOULD JOIN UP WITH THE NORTHERN IOWA COMPLEX
NEAR THE MISSISSIPPI RIVER. THIS COMPLEX IS PRODUCING VERY SIMILAR
CONDITIONS BUT DOES HAVE A BIT MORE POTENTIAL TO PRODUCE SOME WIND
GUSTS. TO ACCOUNT FOR THESE TWO COMPLEXES HAVE INCLUDED A 3 TO 4
HOUR TEMPO GROUP FOR BOTH AIRPORTS WITH SOME GUSTY WINDS AND IFR
CONDITIONS. HOW QUICKLY THE ACTIVITY MOVES EAST IS STILL A LITTLE
QUESTIONABLE SO HAVE HELD ONTO A VCSH INTO THE AFTERNOON. THE NEXT
ROUND OF STORMS BECOMES POSSIBLE LATE THIS AFTERNOON INTO THE
EVENING AS A COLD FRONT MOVES THROUGH THE AREA. STILL A LOT OF
UNCERTAINTY WHETHER THIS ROUND OF STORMS WILL EVEN OCCUR. THE
09.08Z HRRR IS QUICKER TO BRING THE FRONT THROUGH THIS AFTERNOON
AND THUS DOES NOT ALLOW AS MUCH CAPE TO DEVELOP. BECAUSE OF
THIS...IT PASSES THE FRONT THROUGH WITH JUST A FEW SHOWERS ALONG
IT. THE 09.06Z NAM IS SLOWER WITH THE FRONT ALLOWING MORE CAPE TO
DEVELOP AND HAS ANOTHER ROUND OF STORMS ALONG THE FRONT DURING THE
EVENING. NOT KNOWING HOW LONG THE CLOUDS WILL REMAIN PAST THE
MORNING ACTIVITY HAVE OPTED TO REMAIN WITH A VCTS DURING THE
EVENING FOR BOTH SITES. THE CLOUDS SHOULD QUICKLY CLEAR OUT JUST
BEFORE 06Z AS HIGH PRESSURE STARTS TO BUILD IN AND SPREADS DRIER
AIR INTO THE REGION.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
315 AM CDT TUE JUL 9 2013
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 315 AM CDT TUE JUL 9 2013
MAIN CONCERN WILL BE TRACK OF PLAINS THUNDERSTORM COMPLEX THIS
MORNING/TODAY...THEN SEVERE POTENTIAL GOING THIS AFTERNOON.
LOOP OF WATER VAPOR IMAGERY THIS MORNING ALONG WITH RAP 500MB
ANALYSIS SHOWS A FAIRLY VIGOROUS MID-LEVEL TROUGH MOVING OUT OF MT
INTO THE DAKOTAS...WHILE ANOTHER WEAKER WAVE WAS NOTED ACROSS
CENTRAL NEB. 925-850MB MOISTURE TRANSPORT AHEAD OF THESE WAVES WAS
PRODUCING A BROKEN LINE COMPLEX OF THUNDERSTORMS EXTENDING FROM
EASTERN ND/SD...INTO EASTERN NEB. THIS COMPLEX OF STORMS WAS MOVING
EAST AT 30-35KT...MAKING INROADS TOWARD THE AREA. SIMPLE
EXTRAPOLATION BRINGS THIS COMPLEX INTO SOUTHEAST MN/NORTHEAST IA
AROUND 12Z/7AM-ISH.
ARX/HRRR/NMM WRF MODELS DID A PRETTY GOOD JOB INITIALIZING THIS
CONVECTION AND REMAIN IN FAIRLY DECENT AGREEMENT THROUGH THE DAY
TODAY. HAVE TRENDED THE FORECAST TO MATCH UP WITH A BLEND OF THESE
SOLUTIONS. APPEARS THE COMPLEX OF STORMS WILL MAINTAIN
ITSELF...COMING ACROSS THE AREA THIS MORNING AS 925-850MB MOISTURE
TRANSPORT INCREASES/NOSES INTO THE REGION. THIS COMPLEX OF STORMS
HAS A HISTORY OF 30-50KT WINDS ASSOCIATED WITH IT OVER SD.
SO...CANNOT RULE OUT SOME BORDERLINE SEVERE WINDS AS IT ROLLS INTO
OUR AREA. COULD BE INTERESTING GOING INTO THIS AFTERNOON AS THE WRF
MODELS SHOW THIS COMPLEX DEVELOPING A FAIRLY SIGNIFICANT MCV
STRUCTURE. THIS IN TURN HAS THE POTENTIAL OF PRODUCING A
MINI-OUTFLOW/COLD FRONT ON ITS SOUTHWEST FLANK IN THE 18-21Z TIME
FRAME. WITH AMPING SHEAR IN THE 30-40KT RANGE DUE TO THE MCV AND
MORE THAN AMPLE CAPE IN THE 4000-5500J/KG RANGE...LOOKING FOR THE
POSSIBILITY OF A LINE OF SEVERE STORMS WITH DAMAGING WINDS DEVELOPING
ACROSS CENTRAL/SOUTHWEST WI THIS AFTERNOON. THIS OF COURSE WILL ALL
DEPEND ON HOW MUCH CLOUD IS PRESENT WHICH COULD AFFECT THE AMOUNT OF
AVAILABLE INSTABILITY REALIZED. THE POTENTIAL IS DEFINITELY THERE AND
WILL HAVE TO BE WATCHED CLOSELY. ANOTHER THING TO WATCH IS HEAVY
RAINFALL POTENTIAL WITH MUGGY AIRMASS IN PLACE AND PRECIPITABLE WATER
IN THE 2-2.25 INCH RANGE. THIS COULD AID IN TORRENTIAL DOWNPOURS OUT
OF THE STORMS AND SOME LOCALIZED PONDING OF WATER IN POOR DRAINAGE
AREAS.
LOOKING FOR THE MAIN COLD FRONT TO THEN SLIDE SOUTHEAST ACROSS THE
AREA IN THE 00-06Z TIME FRAME. UNCERTAIN ON HOW THIS IS GOING TO
PLAY OUT WITH THE POTENTIAL FOR SEVERE STORMS ALREADY GOING THROUGH
THE AREA THIS AFTERNOON. ATMOSPHERE COULD BE FAIRLY STABILIZED
BEHIND THIS CONVECTION AND COLD FRONT COULD SLIP THROUGH WITH NO
CONVECTION. APPEARS HIGHEST POTENTIAL FOR EVENING CONVECTION MAY BE
ALONG AND NORTH OF I-94 WHERE BETTER 500-300MB PV-ADVECTION WILL
EXIST. EXPECTING COLD FRONT AND ASSOCIATED CONVECTION TO PUSH EAST OF
THE AREA AROUND DAYBREAK AS HIGH PRESSURE BUILDS IN FROM THE
DAKOTAS.
&&
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 315 AM CDT TUE JUL 9 2013
HIGH PRESSURE WILL PRODUCE VERY PLEASANT WEATHER CONDITIONS ACROSS
THE AREA WEDNESDAY AND THURSDAY. LOOK FOR HIGHS IN THE 75-80 DEGREE
RANGE ON WEDNESDAY AND UPPER 70S/LOWER 80S ON THURSDAY. MUCH LOWER
HUMIDITY LEVELS WILL ALSO BE NOTED AS DEWPOINTS HOVER IN THE 50S.
PLAN ON WARMER TEMPERATURES ON FRIDAY ALONG WITH INCREASING HUMIDITY
LEVEL AS THE HIGH SLIDES OFF TO THE EAST AND SOUTH WINDS SET UP
ACROSS THE AREA. LOOK FOR HIGHS IN THE 80S WITH A FEW READINGS
FLIRTING WITH THE 90 DEGREE MARK ACROSS SOUTHEAST MN.
EC/GFS ACTUALLY IN PRETTY GOOD AGREEMENT GOING INTO THE WEEKEND.
BOTH MOVE A COLD FRONT INTO THE UPPER MISSISSIPPI RIVER REGION BY
SUNDAY MORNING...THEN HANG IT UP ACROSS WI INTO CENTRAL IA BY
MONDAY. THIS WILL PRODUCE A CHANCE OF SHOWERS AND THUNDERSTORMS FROM
FRIDAY NIGHT STRAIGHT THROUGH MONDAY. OTHERWISE...LOOK FOR
TEMPERATURES TO BE RIGHT AROUND NORMAL LEVELS IN THE 80S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT
1153 PM CDT MON JUL 8 2013
THE AVIATION FORECAST IS VERY UNCERTAIN FOR THE NEXT 24 HOURS...
PARTICULARLY WITH THUNDERSTORMS. SKIES ARE MAINLY CLEAR AT THE TAF
SITES AS OF 056Z. WITH DEWPOINTS STILL SITTING UP AROUND 70F AND
TEMPERATURES COOLING...ANTICIPATING MVFR BR TO FORM AROUND 09Z.
TO THE WEST...CLUSTERS OF SHOWERS AND THUNDERSTORMS ARE PRESENT
ACROSS THE DAKOTAS INTO NEBRASKA. THESE ARE DEVELOPING AND MOVING
SLOWER THAN PREVIOUS COMPUTER MODELS HAVE FORECAST...THUS HAVE
DELAYED THE TIMING OF THEM IMPACTING THE TAF SITES EVEN MORE.
PRESENTLY HAVE THE SHOWERS AND STORMS IMPACTING RST BETWEEN 13-17Z
AND LSE BETWEEN 14-18Z. STILL NOT ENOUGH CONFIDENCE EXISTS TO
CHANGE THE VCTS TO -TSRA GIVEN THE POTENTIAL FOR THE THUNDERSTORMS
TO BE SCATTERED IN COVERAGE. CONTINUED TO SUGGEST A GENERAL BREAK
IN THE PRECIPITATION UNTIL A COLD FRONT APPROACHES DURING THE
EVENING. HOWEVER...WITH SOME COMPUTER MODELS SHOWING POTENTIAL FOR
SHOWERS AND STORMS TO LINGER THROUGH THE AFTERNOON...MAINTAINED A
VCSH. WITH THE COLD FRONT HAVE ADDED A PERIOD OF VCTS FOR ABOUT 4
HOURS. IT IS POSSIBLE THIS IS TOO LONG...BUT THERE ARE
UNCERTAINTIES ON THE TIMING AND IT DOES APPEAR THE FRONT SHOULD
HAVE SOME THUNDERSTORMS ON IT.
REGARDING THUNDERSTORM IMPACTS. THOSE DURING THE MORNING WILL
LIKELY KNOCK VISIBILITIES AND CEILINGS TO MVFR AND HAVE TO
POTENTIAL TO PRODUCE HEAVY RAIN. THOSE FOR THE EVENING COULD
PRODUCE STRONG TO SEVERE WIND GUSTS...ALONG WITH HEAVY RAIN AND
BRIEF VISIBILITY RESTRICTION.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1153 PM CDT MON JUL 8 2013
.UPDATE...
ISSUED AT 942 PM CDT MON JUL 8 2013
TRYING TO FIGURE OUT THE CONVECTIVE EVOLUTION FORECAST FROM THE
OVERNIGHT HOURS THROUGH TUESDAY REMAINS VERY PROBLEMATIC.
FIRST...A LINE OF SHOWERS AND THUNDERSTORMS SET UP JUST NORTH OF
US-20 AND NEAR THE CLAYTON/GRANT COUNTY LINE. THESE STORMS WERE
ALONG A QUASI-STATIONARY FRONTAL BOUNDARY AND AIDED BY MLCAPES OF
2000-2500 J/KG PER RAP ANALYSIS. THEY HAVE BEEN VERY EFFICIENT
RAIN PRODUCERS WITH RAINFALL RATES OF 1 TO 2 INCHES PER HOUR BEING
OBSERVED IN EDGEWOOD AND GREELEY IA. LACK OF ANY 0-6KM SHEAR HAS
RESULTED IN THE STORMS COLLAPSING. ADDITIONALLY...LOSS OF DAYTIME
HEATING ALLOWING THE CAPE TO DIMINISH...THOUGH DEWPOINTS UP IN
THE MID 70S POOLED ALONG THE BOUNDARY RESULTING IN A SLOW
DIMINISHMENT. ANTICIPATING THESE STORMS MAY END UP FALLING PART IN
THE NEXT HOUR.
NOW FOR THE OVERNIGHT INTO TUESDAY. CONVECTION ACROSS SOUTH DAKOTA
AND NEBRASKA HAS BEEN MUCH LESS THAN WHAT MANY MODELS UP TO THIS
POINT HAD SUGGESTED...INCLUDING HIGH RESOLUTION MODELS. THUS...THE
IDEA OF AN MCS ROLLING OUT OF THIS REGION AND IMPACTING THE
FORECAST AREA LATE TONIGHT IS VERY MUCH IN QUESTION. LOOKING AT
OBSERVATIONAL DATA...THERE IS A SHORTWAVE OVER SOUTHWEST SOUTH
DAKOTA INTO FAR WESTERN NEBRASKA WITH ISOLATED CONVECTION
ACCOMPANYING IT. AHEAD OF THE SHORTWAVE...850MB WINDS HAVE BEEN
INCREASING OVER KANSAS AND NEBRASKA PER RADAR/PROFILER DATA...WITH
HINTS OF A WARM FRONTAL ZONE ACROSS SOUTHERN NEBRASKA. THIS IS
SHOWN TOO IN LATEST SURFACE ANALYSIS. ONCE THESE FEATURES MEET
UP...LIKELY IN CENTRAL/EASTERN NEBRASKA...WOULD IMAGINE CONVECTION
WILL INCREASE THERE. THE CONVECTION WILL LIKELY HEAD EAST THROUGH
THE MEAN FLOW TOWARDS SOUTHERN SECTIONS OF THE FORECAST
AREA...UNLESS IT UPSCALES INTO AN MCS...WHICH THEN MAY HEAD
SOUTHEAST AWAY FROM THE AREA PER BOTH NORMAL CORFIDI VECTORS AND
PROPAGATING CORFIDI VECTORS.
HEADING INTO TUESDAY...THERE ARE INDICATIONS FROM THE 09.00Z
NAM/RAP...08.12Z ECMWF/REGIONAL CANADIAN AND 08.18Z GFS OF 850MB
MOISTURE TRANSPORT PICKING UP ACROSS CENTRAL IOWA...WITH THE NOSE
OF IT POINTED RIGHT INTO THE FORECAST AREA AT 18Z. THIS COULD
CONCEIVABLY INITIATE PLENTY OF CONVECTION FROM LATE MORNING
THROUGH A BULK OF THE AFTERNOON HOURS. THESE WOULD BE EFFICIENT
RAIN PRODUCERS GIVEN DEEP WARM CLOUD DEPTHS AND PRECIPITABLE WATER
VALUES UPWARDS OF 2 INCHES. IF THIS CONVECTION FORMS...BY THE TIME
THE COLD FRONT COMING THROUGH MINNESOTA APPROACHES THE FORECAST
AREA IN THE EVENING...WE MAY NOT HAVE ENOUGH INSTABILITY TO DO
MUCH WITH IT.
WE WILL JUST HAVE TO SEE HOW OVERNIGHT CONVECTION PLAYS
OUT...SINCE AN MCV GOING SOUTH OF US COULD PRODUCE ENOUGH
SUBSIDENCE TO PRECLUDE MUCH CONVECTION IN ITS WAKE FOR TUESDAY.
THE PRESENCE OF THE MCV WOULD LIKE DISTORT THE PROGGED 850MB
MOISTURE TRANSPORT ZONE TOO. TUESDAY THEN WOULD BE A VERY WARM DAY
AGAIN WITH HIGHS ABOVE CURRENT FORECAST...WITH SEVERE WEATHER
POTENTIAL IN THE EVENING AS THE COLD FRONT MOVES IN.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 250 PM CDT MON JUL 8 2013
WARM FRONT SLATED TO WAVER WEST-EAST ACROSS SOUTHERN IA TONIGHT/TUE.
THE LOW LEVEL JET/MOISTURE TRANSPORT FOCUSES INTO THE BOUNDARY
ACROSS CENTRAL IA TONIGHT...AND SHOWER/STORMS SHOULD DEVELOP AS A
RESULT. THE LOW LEVEL FORCING PUSHES NORTHEAST ACROSS THE FORECAST
AREA TUE MORNING WHILE A PIECE OF UPPER LEVEL ENERGY TRACKS FROM THE
NORTHERN PLAINS TO ACROSS THE UPPER MISSISSIPPI RIVER VALLEY BETWEEN
12-18Z. WOULD EXPECT TO SEE A SHIFT NORTHWARD WITH THE MORE
FAVORABLE CONVECTIVE REGION AS A RESULT...MOSTLY ALONG AND NORTH OF
I-90. A STRONGER UPPER LEVEL SHORTWAVE TROUGH PROGGED TO SLIP ACROSS
THE NORTHERN PLAINS AND INTO NORTHERN MN BY 00Z WED. A COLD FRONT
WILL SURGE AHEAD OF THIS SHORTWAVE...GETTING TO THE MISSISSIPPI
RIVER BY 00Z. THE GFS AND NAM BUILD 4000+ J/KG OF MUCAPE AHEAD OF
THE FRONT...WITH 40+ KTS OF 0-6 KM SHEAR. INSTABILITY WILL DEPEND ON
HOW LONG THE MORNING SHOWERS/STORMS LINGER ACROSS THE LOCAL
AREA...AND HOW QUICKLY THE DEBRIS CLOUDS CLEAR. AS IT STANDS...IF
PARAMETERS MANIFEST PER MODELED FORECAST...IT WOULD BE A GOOD SETUP
FOR SEVERE WEATHER. HOWEVER...IF PCPN LINGERS LINGERS...INSTABILITY
WILL BE MUCH LOWER...LESSENING THE SEVERE THREAT. A VERY CONDITIONAL
SEVERE WEATHER THREAT THAT WON/T BECOME CLEARER UNTIL THE AFTERNOON
HOURS.
HERE IS HOW TUE COULD PLAY OUT...MORNING CONVECTION ASSOCIATED WITH
THE LOW LEVEL JET ADVANCES NORTHEAST ACROSS THE REGION. COULD BE
SOME LINGERING SHOWERS/STORMS IN THE AFTERNOON...BUT ENVISION A
BREAK FROM THE WIDESPREAD PCPN CHANCES. SHOWERS/STORMS SPARK ALONG
AND AHEAD OF THE COLD FRONT BY LATE AFTERNOON/EVENING. MAYBE A
BETTER CHANCE NORTH OF I-94. ALSO...BELIEVE THE HIGHER SEVERE RISK
WILL BE DURING THIS TIME.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 250 PM CDT MON JUL 8 2013
HIGH PRESSURE BUILDS ACROSS THE UPPER MISSISSIPPI RIVER VALLEY FROM
THE WEST ON WEDNESDAY...AND LOOKS TO BE THE MAIN WEATHER INFLUENCE
THROUGH THE BETTER PART OF FRIDAY. THE HEAT/HUMIDITY OF THE PAST FEW
DAYS WILL SWEEP EAST DURING THIS PERIOD...WITH COMPARATIVELY COOLER
AND LESS MUGGY CONDITIONS RESULTING.
AN UPPER LEVEL SHORTWAVE TROUGH IS THEN SLATED TO DRIVE FROM THE PAC
NW TO ACROSS SOUTHERN CANADA FOR THE UPCOMING WEEKEND. WHILE CURRENT
TRENDS FAVOR KEEPING MOST OF THE UPPER LEVEL ENERGY NORTH OF THE
FORECAST AREA...THE GFS AND ECMWF WOULD SLIDE AN ASSOCIATED COLD
FRONT ACROSS THE REGION. WITH THE WINDS FLIPPING TO THE SOUTH AS THE
HIGH EEKS TO THE EAST...LOW LEVEL MOISTURE WOULD INCREASE AHEAD OF
THE SFC BOUNDARY...AS WOULD INSTABILITY. EXPECT SOME CONVECTION
AROUND THE FRONT AS RESULT. DETAILS ON WHEN/WHERE ISN/T CLEAR AT
THIS TIME...WITH SOME MODEL DIFFERENCES ON TIMING AND PLACEMENT OF
THE RELEVANT FEATURES. THE SFC FRONT COULD THEN GET HUNG UP FROM
WEST TO EAST ACROSS THE REGION...SERVING AS A POSSIBLE SHOWER/STORM
FOCUS THROUGH THE WEEKEND. WILL LEAN ON THE CONSENSUS/EC SOLUTION
FOR PCPN CHANCES FOR NOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1153 PM CDT MON JUL 8 2013
THE AVIATION FORECAST IS VERY UNCERTAIN FOR THE NEXT 24 HOURS...
PARTICULARLY WITH THUNDERSTORMS. SKIES ARE MAINLY CLEAR AT THE TAF
SITES AS OF 056Z. WITH DEWPOINTS STILL SITTING UP AROUND 70F AND
TEMPERATURES COOLING...ANTICIPATING MVFR BR TO FORM AROUND 09Z.
TO THE WEST...CLUSTERS OF SHOWERS AND THUNDERSTORMS ARE PRESENT
ACROSS THE DAKOTAS INTO NEBRASKA. THESE ARE DEVELOPING AND MOVING
SLOWER THAN PREVIOUS COMPUTER MODELS HAVE FORECAST...THUS HAVE
DELAYED THE TIMING OF THEM IMPACTING THE TAF SITES EVEN MORE.
PRESENTLY HAVE THE SHOWERS AND STORMS IMPACTING RST BETWEEN 13-17Z
AND LSE BETWEEN 14-18Z. STILL NOT ENOUGH CONFIDENCE EXISTS TO
CHANGE THE VCTS TO -TSRA GIVEN THE POTENTIAL FOR THE THUNDERSTORMS
TO BE SCATTERED IN COVERAGE. CONTINUED TO SUGGEST A GENERAL BREAK
IN THE PRECIPITATION UNTIL A COLD FRONT APPROACHES DURING THE
EVENING. HOWEVER...WITH SOME COMPUTER MODELS SHOWING POTENTIAL FOR
SHOWERS AND STORMS TO LINGER THROUGH THE AFTERNOON...MAINTAINED A
VCSH. WITH THE COLD FRONT HAVE ADDED A PERIOD OF VCTS FOR ABOUT 4
HOURS. IT IS POSSIBLE THIS IS TOO LONG...BUT THERE ARE
UNCERTAINTIES ON THE TIMING AND IT DOES APPEAR THE FRONT SHOULD
HAVE SOME THUNDERSTORMS ON IT.
REGARDING THUNDERSTORM IMPACTS. THOSE DURING THE MORNING WILL
LIKELY KNOCK VISIBILITIES AND CEILINGS TO MVFR AND HAVE TO
POTENTIAL TO PRODUCE HEAVY RAIN. THOSE FOR THE EVENING COULD
PRODUCE STRONG TO SEVERE WIND GUSTS...ALONG WITH HEAVY RAIN AND
BRIEF VISIBILITY RESTRICTION.
&&
.HYDROLOGY...(TUESDAY)
ISSUED AT 250 PM CDT MON JUL 8 2013
PWS CLOSE TO 2 INCHES THROUGH TUE...AROUND 170 PERCENT OF
NORMAL...WHILE WARM CLOUD DEPTH IS 3500-4000 M. ALL SUPPORT THE
POTENTIAL FOR HEAVY RAIN. HOWEVER...THE EXPECTED PCPN LOOKS
TRANSITORY...NOT LINGERING NOR MUCH TRAINING....WHILE FFG IS 2.5-3
INCHES IN 3 HOURS. THE MOISTURE TRANSPORT ISN/T OVERLY STRONG NOR
DOES IT FOCUS FOR A PROLONGED PERIOD. SO...WHILE THE ATMOSPHERE
COULD SUPPORT HEAVY RAIN...OTHER ASPECTS MINIMIZE A FLASH FLOOD
THREAT. IF PCPN RATES COULD BECOME HIGH ENOUGH...FLASH FLOODING OR
URBAN/CITY FLOODING WOULD BE POSSIBLE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...AJ
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION...AJ
HYDROLOGY....DAS
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1132 PM CDT MON JUL 8 2013
.UPDATE...
ISOLATED THUNDERSTORMS CONTINUE TO POP-UP ALONG OUTFLOW BOUNDARIES
WITHIN REGION OF SURFACE MOISTURE FLUX CONVERGENCE OVER FAR SRN WI AND
NRN IL. RAPID UPDATE/HI-RES MODELS CONTINUE TO SHOW A DOWNWARD
TREND TO CONVECTION OVER THE REGION THROUGH THE NIGHT WITH THE
FOCUS SHIFTING TO MCS DEVELOPMENT CURRENTLY OCCURRING OVER THE
DAKOTAS MOVING EAST THROUGH IOWA/MINNESOTA AND REACHING WESTERN
WISCONSIN SOMETIME BETWEEN 12Z AND 18Z TUESDAY.
TIMING DIFFERENCE IS CRITICAL TO SEVERE POTENTIAL FOR TUESDAY AS
MCS TRACK WILL HAVE AN IMPACT ON LOCATION OF EFFECTIVE BOUNDARY.
PRECIPITATION TOO LONG INTO THE DAY AND/OR CLOUD DEBRIS COULD
REDUCE HEATING AND SUBSEQUENT INSTABILITY. OPERATIONAL MODELS
STILL LOOKING AT MAIN CONVECTIVE EVENT TO OCCUR LATE
AFTERNOON/EVENING AHEAD OF...AND WITH PASSAGE OF MAIN SHORT WAVE
TROUGH AND ASSOCIATED SURFACE COLD FRONT.
LIGHT FOG OVER MAINLY THE NORTHEAST THIRD OF FORECAST AREA...WHERE
LAKE BREEZE...ENHANCED BY OUTFLOW FROM EARLIER STORMS HAS COOLED
TEMPS TOWARD DEW POINTS THAT ARE LOWER THAN EARLIER IN THE DAY AS
WELL WITH SLIGHTLY DRIER AIR ADVECTING IN ON NE WINDS. RUC AND NAM
VISIBILITY FORECASTS HOLD CHANCES FOR 1/4 MILE TO THE EAST OF THE
KETTLE MORAINE..WITH THE LATEST NAM MOS GUIDANCE KEEPING VSBYS NO
LOWER THAN 1 TO 2 MILES. WILL KEEP PATCHY FOG FOR NOW AND SEE HOW
FOG DEVELOPS...THOUGH SBM IS DOWN TO 1/4 MILE.
&&
.AVIATION/06Z TAFS/...
EXPECT CURRENT DEVELOPING MVFR VSBYS TO FALL TO IFR IN FOG OVERNIGHT.
NOT EXPECTING LIFR...BUT WILL HAVE TO WATCH KENW FOR 1/2 MILE
VSBYS. DO NOT EXPECT MUCH MORE IN THE WAY OF CONVECTION UNTIL
APPROACH OF SHORT WAVE TROUGH AND SURFACE COLD FRONT TRAILING FROM
ATTENDANT SURFACE LOW CROSSING SRN CANADA TUESDAY. MODELS SUGGEST
AN MCS...OR ITS REMAINS...MOVING ACROSS SRN WI TUESDAY MORNING
INTO EARLY AFTERNOON...THEN THE SECOND ROUND WITH A BETTER CHANCE
OF SEVERE IN THE AFTERNOON AND EVENING WITH THE FRONT.
&&
.MARINE...
ADDED AREAS OF FOG IN THE NSH BASED ON SHORE BASED WEB CAMS JUST
BEFORE DARK AND WITH FOG PRODUCT SHOWING AN EXPANDING AREA OF LOW
STRATUS OVER MAINLY THE NORTHERN HALF OF THE LAKE. MODEL LOW-LAYER
WINDS SEEM TO FAVOR HOLDING THE LOW STRATUS OFF TO THE EAST...BUT WILL
HAVE TO BE WATCHED FOR POSSIBLE MARINE DENSE FOG ADVISORY IF IT
MOVES TO THE WESTERN SHORE. POSSIBLE THUNDERSTORMS IN THE LATE
MORNING/EARLY AFTERNOON WITH MCS...THEN SECOND ROUND OF STORMS
WITH THE BETTER POTENTIAL FOR SEVERE IN THE LATE AFTERNOON/EVENING.
&&
.PREV DISCUSSION... /ISSUED 305 PM CDT MON JUL 8 2013/
SHORT TERM...
TONIGHT - CONFIDENCE...MEDIUM
WARM/UNSTABLE AIRMASS HAS GENERATED A FEW SHRA ACROSS NE CWA THIS
AFTERNOON VICINITY OF INSTABILITY GRADIENT AND SURFACE FRONTOGENESIS
PER SPC MESO PAGE. OVERALL 500 MILLIBAR RIDGING SHOULD KEEP MOST
AREAS DRY FOR MUCH OF THE NIGHT. FOCUS SHIFTS BACK TO THE WEST WITH
THE NEXT SHORT WAVE APPROACHING. IN RESPONSE TO THE LOW LEVEL
CYCLOGENESIS...A STRENGTHENING LOW LEVEL JET WILL BRING ANOTHER
SURGE OF MOISTURE INTO THE UPPER MIDWEST. EXPECTING AN MCS TO
DEVELOP WEST OF WISCONSIN OVERNIGHT...AND PERHAPS AFFFECT THE SW CWA
LATE IN THE NIGHT. WARM AND HUMID CONDITIONS WILL PERSIST THROUGH
THE OVERNIGHT HOURS. MAV/MET AND SREF PROBS POINTING TO POTENTIAL
FOR FOG. IN FACT SOME RATHER LOW VSBYS FORECAST BY MOS. WITH THE
ABUNDANT LOW LEVEL MOISTURE...SOUTHWARD SAGGING FRONTAL
BOUNDARY...AND LIGHT WIND REGIME...WILL HAVE SOME FOG IN THE GRIDS
FOR LATER TONIGHT.
TUESDAY - CONFIDENCE...MEDIUM
COMPLEX DAY SETTING UP. THE MORNING WILL BE COMPRISED OF DEALING
WITH FOG TRENDS ALONG AND NORTH OF WHERE SURFACE BOUNDARY IS
SITUATED. IN ADDITION CONVECTION LIKELY ONGOING IN PARTS OF THE
AREA. AS THE MCS ARRIVES ANY FOG SHOULD GRADUALLY THIN OUT. THEN THE
WAITING GAME WILL START FOR RENEWED CONVECTIVE DEVELOPMENT AS THE
DAY WEARS ALONG. A MORE VIGOROUS SHORTWAVE WILL BE APPROACHING FROM
MN LATER IN THE DAY. DETAILS OF WHERE THE LOW LEVEL BOUNDARY SETS UP
WILL HAVE TO BE SORTED OUT AFTER MORNING CONVECTION...THOUGH
MAJORITY OF AVAILABLE GUIDANCE/CIPS ANALOGS AND SPC SWODY2 SUPPORT
STRONG/SEVERE STORMS REFIRING WITH A NOD TOWARDS DAMAGING WINDS AND
HEAVY RAINS. PROGGD ML CAPE VALUES/LI/S/PWS ARE ALL SUPPORTIVE OF
MODERATE TO STRONG INSTABILITY AND AN AIRMASS LOADED WITH MOISTURE.
SO STORMS WILL BE VERY EFFICENT RAIN PRODUCERS.
TUESDAY NIGHT AND WEDNESDAY...FORECAST CONFIDENCE HIGH.
THE MAIN MID/UPPER SHORTWAVE MOVES ACROSS LAKE SUPERIOR THURSDAY NIGHT
AND EXITS THE LAKE HURON AREA WEDNESDAY. SOUTHERN WISCONSIN IS IN THE
RIGHT ENTRANCE REGION OF AN 85 KNOT 250 MB JET TUESDAY EVENING.
THE UPPER FLOW IS DIFLUENT WITH WEAK TO MODERATE UPPER DIVERGENCE.
THE CWASP VALUES STILL APPROACH 65 PERCENT ON THE NAM DURING THE
AFTERNOON AND EVENING. ZERO TO 3 KM EHI VALUES ARE QUITE HIGH ACROSS
NORTHWEST ILLINOIS EARLY IN THE EVENING...WITH VALUES AROUND 5.
EHI VALUES ARE NEAR 2 TO 3 ACROSS MUCH OF SOUTH CENTRAL WISCONSIN
AND WESTERN PORTIONS OF SOUTHEAST WISCONSIN INDICATING SOME
TORNADO POSSIBILITY AS WELL. THE CIPS ANALOGS HAVE MAINLY SEVERE
WIND EVENTS...BUT THERE ARE SOME TORNADO EVENTS WITH
PROBABILITIES OF 2 TO 5 PCT WITHIN 40 KM OF A GRID POINT OVER MUCH
OF THE FORECAST AREA. MUCH WILL DEPEND ON WHETHER A MORNING
MESOSCALE CONVECTIVE COMPLEX MOVES ACROSS THE AREA...AND WHERE THE
RETURNING WARM FRONTAL BOUNDARY ENDS UP. THE COLD FRONT EXITS THE
FAR SOUTHEAST TUESDAY NIGHT. UNTIL THEN WITH CAPE VALUES AROUND
1500 J/KG IN THE EVENING...THE SEVERE AND HEAVY RAIN THREAT SHOULD
CONTINUE.
THE 850/700 MB THERMAL RIDGE DROPS SOUTH INTO ILLINOIS TUESDAY
NIGHT. DRYING OCCURS AT 850/700 MB AND SURFACE DEW POINTS DROP
INTO THE LOWER 60S WEDNESDAY AFTERNOON. THERE IS CONSIDERABLE
DRYING IN THE MID AND LOW LEVELS...WITH A STABLE LAYER AROUND 6 TO
10 THSD FT IN THE NAM FORECAST SOUNDINGS.
WEDNESDAY NIGHT AND THURSDAY...FORECAST CONFIDENCE HIGH.
THE SHORTWAVE REACHES SOUTHEAST CANADA AND THE EASTERN
GREAT LAKES...BUT SOUTHERN WISCONSIN IS STILL SOMEWHAT IN THE
CYCLONIC FLOW ON THE BACK SIDE OF THE TROUGH. ZERO TO 1 KM CAPE
VALUES REACH 600 J/KG THURSDAY AFTERNOON WITH STEEP LOW LEVEL
LAPSE RATES. HOWEVER MID LEVELS ARE VERY DRY AND WOULD LIKELY
LIMIT ANY DEEP MOIST CONVECTION DUE TO ENTRAINMENT.
THICKNESS VALUES DROP TO 564 TO 567 DECAMETERS AS A LARGE SURFACE
HIGH BUILDS INTO THE UPPER MISSISSIPPI VALLEY AND WISCONSIN.
LONG TERM...
THURSDAY NIGHT AND FRIDAY...FORECAST CONFIDENCE HIGH.
THE UPPER TROUGH DROPS SOUTH ACROSS THE EASTERN U.S. WITH A LARGE
MID/UPPER RIDGE BUILDING FROM THE SOUTHERN ROCKIES INTO WISCONSIN.
THE SURFACE HIGH IS OVER THE GREAT LAKES AND UPPER OHIO RIVER
VALLEY. TEMPERATURES SHOULD BE ON THE REBOUND AND COULD RISE ABOVE
THE GFS MOS VALUES.
SATURDAY AND SUNDAY...FORECAST CONFIDENCE MEDIUM TO HIGH.
THE UPPER TROUGH/LOW RETROGRADES INTO THE GULF COAST AREA WITH
THE LARGE RIDGE STILL FROM THE SOUTHERN ROCKIES INTO WISCONSIN.
THE SURFACE HIGH REMAINS IS OVER THE GREAT LAKES. WARM AIR
ADVECTION OCCURS FRIDAY NIGHT AND SATURDAY. BOTH THE 12Z GFS AND
00Z ECMWF HAS SOME PRECIPITATION OVER NORTHWEST WISCONSIN...BUT
ARE GENERALLY DRY AS IT APPROACHES SOUTHERN WISCONSIN SATURDAY...SO
JUST A SLIGHT CHANCE OF SHOWERS AT BEST MAINLY NORTHWEST OF
MADISON BY SATURDAY AFTERNOON.
MONDAY...FORECAST CONFIDENCE MEDIUM.
A SHORTWAVE MOVES ACROSS SOUTHERN CANADA WITH THE MID/UPPER RIDGE
EXTENDING MORE EAST TO WEST ACROSS THE MID SECTIONS OF THE U.S.
A WEAK COLD FRONT SHOULD MOVE ACROSS SOUTHERN WISCONSIN BUT MODEL
PRECIPITATION AMOUNTS ARE LIGHT.
AVIATION/00Z TAFS/...
ELONGATED FRONTAL BOUNDARY EXTENDS FROM NORTHERN LOWER MI THROUGH
CENTRAL WI INTO CENTRAL IOWA. PLENTY OF MVFR CU EXPECTED TO MOSTLY
DISSIPATE WITH LOSS OF HEATING. ISOLD SHRA WILL AFFECT LOCALES
MAINLY NORTH OF TAF SITES THIS EVE B4 DISSIPATING. MET/MAV MOS
DATA ALONG WITH SREF CIG/VSBY PROGS BEAR OUT CONCERN FOR LOW
CLOUDS/FOG WITH LIGHTER WIND REGIME EVOLVING TONIGHT INTO EARLY
WEDNESDAY WITH SOUTHWARD SAGGING FRONTAL BOUNDARY. CONVECTION
LIKELY TO REDEVELOP LATER TONIGHT INTO TUESDAY MORNING WITH
RENEWED LOW LEVEL JET AND APPROACH OF ANOTHER 500 MILLIBAR
SHORTWAVE. THEN A BREAK BEFORE MORE STORMS ARRIVE MID/LATE
AFTERNOON TIME FRAME INTO THE EVENING HOURS. SOME OF THE STORMS
MAY BECOME SEVERE.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...REM
TONIGHT/TUESDAY AND AVIATION/MARINE...COLLAR
TUESDAY NIGHT THROUGH MONDAY...HENTZ
AREA FORECAST DISCUSSION
NWS TUCSON AZ
300 AM MST THU JUL 11 2013
.SYNOPSIS...ABUNDANT MOISTURE WILL PRODUCE SCATTERED THUNDERSTORMS
THROUGH THIS EVENING WITH ISOLATED THUNDERSTORMS CONTINUING LATE
TONIGHT. THUNDERSTORM CHANCES WILL GRADUALLY DECREASE FRIDAY THROUGH
SUNDAY. THEREAFTER...ADEQUATE MOISTURE WILL CONTINUE THE CYCLE OF
MAINLY AFTERNOON AND EVENING THUNDERSTORMS MONDAY THROUGH WEDNESDAY.
COOLER DAYTIME TEMPERATURES TODAY FOLLOWED BY A WARMING TREND INTO
EARLY NEXT WEEK.
&&
.DISCUSSION...SCATTERED SHOWERS AND ISOLATED TSTMS ONGOING FROM THE
TUCSON METRO AREA WESTWARD TO NORTHWESTWARD INTO WRN PIMA/SOUTH
CENTRAL PINAL COUNTIES. BULK OF THIS ACTIVITY IS EXPECTED TO MOVE
OUT OF THIS FORECAST AREA AROUND 14Z. HOWEVER...THE 11/08Z RUC HRRR
DEVELOPS PRECIP ECHOES ACROSS CENTRAL/ERN PIMA COUNTY BY 17Z.
PRECIP CELLS ARE PROGGED TO BECOME MORE WIDESPREAD BY EARLY THIS
AFTERNOON AND ARE DEPICTED TO BE MOSTLY NORTH AND EAST OF TUCSON BY
22Z. THE OFFICIAL FORECAST DEPICTS SCATTERED SHOWERS/TSTMS FROM LATE
THIS MORNING INTO THIS EVENING. HAVE MAINTAINED A SLIGHT CHANCE OF
SHOWERS/TSTMS AREA-WIDE LATE TONIGHT.
11/00Z GFS/ECMWF GENERALLY AGREE THAT UPPER HIGH CENTERED OVER THE
CENTRAL CONUS PLAINS FRI-SAT WILL MOVE TOWARD THE FOUR CORNERS
REGION EARLY NEXT WEEK. GFS/ECMWF DEPICT A GRADUAL DECREASE IN MID-
LEVEL MOISTURE THIS WEEKEND. THUS...SCATTERED AFTERNOON AND EVENING
SHOWERS/TSTMS FRI-SAT ARE FORECAST TO DECREASE IN COVERAGE SUN.
THERE WILL STILL BE ENOUGH MOISTURE FOR ISOLATED-SCATTERED SHOWERS/
TSTMS SUN AFTERNOON AND SUN EVENING.
THEREAFTER...SCATTERED MAINLY AFTERNOON AND EVENING SHOWERS/TSTMS
WILL RETURN MON-WED AS THE UPPER HIGH REMAINS QUASI-STATIONARY NEAR
THE FOUR CORNERS REGION. HAVE NOTED THAT THE 11/00Z GFS/ECMWF WERE
MARKEDLY FURTHER SOUTH WITH THE PATH OF AN UPPER LEVEL LOW PRESSURE
SYSTEM VERSUS PREVIOUS SOLUTIONS. THUS...HAVE TRIMMED POPS SOMEWHAT
PARTICULARLY NEXT MON.
HIGH TEMPS TODAY WILL AVERAGE ABOUT 2-5 DEGS F COOLER VERSUS WED. A
WARMING TREND WILL THEN OCCUR FRI-MON FOLLOWED BY COOLER DAYTIME
TEMPS TUE-WED.
&&
.AVIATION...GRADUAL CLEARING FROM THE SE THROUGH 11/18Z LEAVING
BEHIND SCT140 SCT-BKN350. THEN EXPECT ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS THE REGION WITH
ISOLD MVFR CONDS. A BASIC DIURNAL WIND PATTERN IS EXPECTED AWAY FROM
THUNDERSTORMS WITH ERRACTIC AND GUSTY WINDS NEAR THUNDERSTORMS.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...SCATTERED MAINLY LATE AFTERNOON THROUGH EARLY
MORNING SHOWERS AND THUNDERSTORMS WILL CONTINUE WITH A SLIGHT
DIMINISHING TREND INTO THE WEEKEND. THE STRONGER THUNDERSTORMS WILL
PRODUCE GUSTY AND ERRATIC WINDS AND LOCALLY HEAVY RAINS. OUTSIDE OF
THE THUNDERSTORM ACTIVITY...GENERALLY NORMAL DIURNAL WIND TRENDS ARE
EXPECTED TO OCCUR THROUGH THE WEEKEND. DAYTIME RELATIVE HUMIDITIES
WILL RANGE FROM THE 20S TO 30S WITH GOOD NIGHTTIME RECOVERIES
THROUGH FRIDAY THEN THERE WILL BE A SLIGHT DRYING TREND INTO THE
WEEKEND.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
DISCUSSION...FRANCIS
AVIATION/FIRE WEATHER...CERNIGLIA
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
255 AM MST THU JUL 11 2013
.SYNOPSIS...
FAVORABLE SOUTHERLY FLOW WILL CONTINUE TO IMPORT DEEPER MONSOON
MOISTURE INTO THE REGION OVER THE NEXT COUPLE DAYS. THIS WILL LEAD
TO MORE NUMEROUS SHOWERS AND THUNDERSTORMS ACROSS THE ENTIRE AREA
LASTING THROUGH FRIDAY. THE INCREASED MOISTURE WILL ALSO RESULT IN
COOLER DAYTIME TEMPERATURES FOR THE REST OF THE WORK WEEK. WARMER
TEMPERATURES AND A GENERAL DECREASE IN THUNDERSTORM ACTIVITY CAN BE
EXPECTED OVER THE WEEKEND AND INTO EARLY NEXT WEEK.
&&
.DISCUSSION...
A BROAD SYNOPTIC SCALE INVERTED TROUGH CONTINUES TO PROPAGATE
WESTWARD TOWARDS THE GULF OF CALIFORNIA...WITH SMALL VORTICITY
CENTERS (POSSIBLY CONVECTIVELY ENHANCED) ALONG THE INTERNATIONAL
BORDER HELPING FORCE LARGE SCALE ASCENT AND CONVECTION THROUGH
SOUTHERN ARIZONA. DESPITE FAVORABLE MOISTURE PROFILES PER 00Z
SOUNDING DATA (DEEP WELL MIXED 11-14 G/KG OF MOISTURE)...WEAK
CAPPING AROUND 750MB STILL EXISTED PRECLUDING ORGANIZED STORMS FROM
SURVIVING OFF HIGHER TERRAIN. HOWEVER...OBJECTIVE ANALYSIS DEPICTS A
GENERAL COOLING AND MOISTENING OF THE ATMOSPHERIC COLUMN THROUGH
THE MORNING HOURS...LARGELY ERODING INHIBITION AND SUPPORTING
ISOLD/SCT SHOWER AND STORMS THROUGH MUCH OF THE CNTRL AND ERN PARTS
OF THE FORECAST AREA.
ONCE AGAIN EARLY THIS MORNING...NEAR TERM HRRR REFLECTIVITY
FORECASTS HAVE CAPTURED THE GENERAL TREND OF THE CURRENT
ACTIVITY...WITH SREF PROBABILITIES...DETERMINISTIC ECMWF...AND NMM
HIGH RESOLUTION CORE FORECASTS MOST AGGRESSIVE IN EXPANSION OF
ECHOES/QPF THROUGH SWRN ARIZONA THROUGH 18Z. GIVEN CURRENT RADAR
TENDS...COULD NOT DISCOUNT THESE MORE BULLISH SOLUTIONS...AND HAVE
RAISED POPS INTO A HIGHER CHANCE CATEGORY. MAY NEED FURTHER
REVISIONS/EXPANSION OF POPS UPDATED LATER THIS MORNING SHOULD TRENDS
CHANGE.
OTHERWISE...NOT A TREMENDOUS AMOUNT OF CONFIDENCE IN THE REMAINDER
OF THE FORECAST THIS AFTERNOON AND EVENING...PARTICULARLY REGARDING
CONVECTIVE EVOLUTION. STRANGELY...MANY OF THE MODELS TRADITIONALLY
BULLISH ON CONVECTION AND WITH HIGH FALSE ALARM RATES SHOW AN
UNUSUAL DEARTH OF RAINFALL THIS AFTERNOON/EVENING. THIS MAY BE DUE
TO AN ASSUMPTION OF CONVECTIVE CONTAMINATION AND CLOUD COVER
LINGERING OVER MUCH OF THE CWA DURING PEAK HEATING. ONE DISTINCT
TREND AMONG VIRTUALLY ALL MODELS WAS MORE FOCUS OF CONVECTION OVER
SERN CALIFORNIA...AND HAVE SUBSTANTIALLY INCREASED POPS IN THIS
REGION. INTERROGATION OF FORECAST SOUNDINGS FROM YUMA-IMPERIAL
INDICATE LOW MLCAPE...YET UNCAPPED PROFILES IN A WEAKLY SHEARED
ENVIRONMENT. WHILE ORGANIZED SEVERE STORMS WOULD NOT BE
EXPECTED...T/TD SPREADS ON THE ORDER OF 40F COULD STILL SUPPORT
ISOLD HIGHER WIND GUSTS. IN ADDITION...WHILE NOT THE CLASSIC HEAVY
RAIN SOUNDING...PWATS IN EXCESS OF 1.75 INCHES JUXTAPOSED WITH
UNIDIRECTIONAL WIND PROFILES OF LITTLE VERTICAL SPEED SHEAR MAY
SUPPORT TRAINING ECHOES AND LOCALLY HEAVY RAINFALL.
DEEP SOUTHERLY FLOW AND AMPLE MOISTURE PROFILES WILL PERSIST INTO
FRIDAY...SUGGESTING ACTIVE MONSOON THUNDERSTORM ACTIVITY.
HOWEVER...RECENT MODEL OUTPUT IS NOT PARTICULARLY IMPRESSIVE
REGARDING CONVECTIVE COVERAGE FRIDAY AFTERNOON/EVENING. AT THIS
POINT...IT APPEARS THE LACK OF A DYNAMIC TRIGGER...NEUTRAL JET
STRUCTURE...AND THE FIRST SIGNS OF A RETROGRESSIVE RIDGE MAY BE TO
BLAME. WITH MANY OF THE INGREDIENTS STILL PRESENT THROUGH THE
ATMOSPHERE...COULD NOT TOTALLY ELIMINATE THE POTENTIAL FOR AN ACTIVE
EVENING...HOWEVER HAVE GENERALLY TEMPERED BACK POPS FOR ALL BUT THE
HIGHER TERRAIN LOCATIONS.
A SUBTLE SHIFT IN THE OVERALL CONUS FLOW PATTERN WILL TAKE PLACE
OVER THE WEEKEND...AS A PROGRESSIVE ERN PACIFIC/PAC NW TROUGH
TRANSLATES INTO SOUTHERN CANADA CAUSING A RETROGRESSION OF FEATURES
SOUTH OF THE PRIMARY NORTHERN STREAM JET. AS SUCH...AN H5 594DM
RIDGE AXIS WILL SETTLE BACK OVER ARIZONA BRINGING A SLIGHT DRYING
TREND AND MORE LARGE SCALE SUBSIDENCE. ABOVE NORMAL TEMPERATURES AND
LOWER PRECIPITATION CHANCES OUTSIDE OF SOUTHERN GILA COUNTY APPEAR
MOST LIKELY THROUGH AT LEAST MONDAY.
BOTH THE OPERATIONAL GFS AND ECMWF NOW SHOW THE AFOREMENTIONED RIDGE
AXIS PERSISTING ACROSS THE AREA MUCH LONGER THAN PREVIOUSLY
FORECAST...WITH AN INVERTED TROUGH DECAYING AND BECOMING DEFLECTED
WELL SOUTH INTO MEXICO THROUGH THE MIDDLE OF NEXT WEEK (AS OPPOSED
TO PREVIOUS FORECASTS BRINGING A CIRCULATION CENTER DIRECTLY OVER
THE FORECAST AREA). WHILE FORECAST CONFIDENCE IN NOT OVERWHELMINGLY
HIGH...THE MODEL TREND DOES SUPPORT A FORECAST TOWARDS WARMER
TEMPERATURES AND LOWER PRECIPITATION CHANCES EVEN INTO THE MIDDLE OF
NEXT WEEK. HAVE NOT YET FULLY BOUGHT INTO THE MAGNITUDE OF WARMTH
ADVERTISED BY NUMERICAL GUIDANCE...BUT HAVE CERTAINLY INCREASED
VALUES TO A NEAR NORMAL THRESHOLD.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX...KIWA AND KSDL...
MOSTLY MID LEVEL DEBRIS CIGS AON 10KFT AGL WILL PERSIST OVERNIGHT
FOR THE PHX TERMINALS. WIDESPREAD CONVECTIVE ACTIVITY ACROSS THE PHX
METRO HELD OFF ANOTHER NIGHT...BUT STILL PERSISTS ACROSS THE HIGHER
TERRAIN EAST OF PHOENIX. LIGHT SHOWERS AND ISOLATED THUNDER MAY WORK
THEIR WAY DOWN IN TO THE LOWER DESERTS AND THE PHX TERMINALS
OVERNIGHT...BUT CONFIDENCE AT THIS TIME IS TOO LOW TO WARRANT
INCLUSION IN THE 06Z TAF PACKAGE. OUTSIDE OF PASSING SHOWER
ACTIVITY...SURFACE WINDS WILL REMAIN WESTERLY OVERNIGHT BEFORE
BECOMING MORE VARIABLE IN NATURE CLOSER TOWARDS SUNRISE.
SOUTHEAST CA AND SOUTHWEST AZ...INCLUDING KIPL AND KBLH...
MID TO HIGH LEVEL BKN TO OVC CIGS WILL FILTER INTO THE AREA FROM THE
EAST AND SOUTH AS CONVECTIVE ACTIVITY BACK ACROSS SOUTH CENTRAL
ARIZONA CONTINUES TO DISSIPATE. ACTIVITY MAY DRIFT WEST ENOUGH TO
GENERATE VCSH ACTIVITY NEAR KBLH BY THE EARLY MORNING HOURS. OVERALL
WINDS WILL REMAIN SOUTHEASTERLY IN NATURE WITH PERIODIC AFTERNOON
GUSTS TO NEAR 20KTS POSSIBLE.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY...
CHANCES FOR MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS
WILL REMAIN INTO THE EARLY WEEKEND...BUT A DRYING TREND WILL KEEP
STORMS MAINLY CONFINED TO THE HIGHER TERRAIN NORTH AND EAST OF
PHOENIX SUNDAY AND MONDAY. THE DRYING TREND WILL BRING MINIMUM
HUMIDITIES INTO THE TEENS ACROSS THE LOWER DESERTS FOR SUNDAY AND
MONDAY. OTHER DAYS WILL GENERALLY SEE AFTERNOON MINIMUM VALUES ONLY
DROPPING INTO THE 20-30 PERCENT RANGE. OVERNIGHT RECOVERY SHOULD BE
GOOD TO EXCELLENT WITH READINGS CLIMBING ABOVE 40 PERCENT MOST
NIGHTS. GUSTY WINDS ARE POSSIBLE EACH DAY...AS OUTFLOW BOUNDARIES
PROPAGATE AWAY FROM DEVELOPING SHOWERS AND THUNDERSTORMS.
&&
$$
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...MO
AVIATION...NOLTE
FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1245 AM EDT THU JUL 11 2013
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL CROSS INTO EASTERN CANADA AND DRAG A COLD
FRONT INTO THE REGION LATE TONIGHT. THE COLD FRONT WILL MOVE SLOWLY
THROUGH THE AREA ON THURSDAY BEFORE STALLING JUST TO THE SOUTH AND
EAST OF THE REGION ON FRIDAY AND THEN DISSIPATE OVER THE WEEKEND.
HIGH PRESSURE WILL BUILD INTO THE REGION OVER THE WEEKEND AND THEN
BECOME ABSORBED INTO THE RETROGRADING BERMUDA HIGH PRESSURE OVER THE
WESTERN ATLANTIC EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
WITH THE EARLY MORNING UPDATE, WE INCREASED POPS A BIT AND ADDED
THUNDER FOR THE NEXT FEW HOURS IN OUR FAR SOUTHERN DELMARVA ZONES
AS LATEST RADAR IMAGERY SHOWS CONTINUED SHOWER ACTIVITY WITH SOME
EMBEDDED THUNDER EDGING CLOSER TO THE AREA FROM THE SOUTHWEST.
THIS ACTIVITY IS ALSO REFLECTED IN THE HRRR AND SHOULD CONTINUE TO
GRADUALLY DISSIPATE BY AROUND 06Z OR 07Z. ELSEWHERE, SOME
CONVECTIVE ACTIVITY PASSING OVER OUR FAR NORTHWEST ZONES INTO THE
POCONOS HAS SINCE DISSIPATED, AND WE LOWERED POPS ACCORDINGLY.
OVERALL, WE KEPT LOW CHANCE POPS FOR SCATTERED SHWRS THROUGH THE
REMAINDER OF THE OVERNIGHT ACROSS THE FORECAST AREA AS A MID LEVEL
SHORTWAVE APPROACHES, GRADUALLY INCREASING THE POPS AFTER
DAYBREAK, AS MOST MODEL GUIDANCE SHOWS THE SHORTWAVE AND SOME
CHANNELIZED VORTICITY ARRIVING INTO THE REGION BY THEN.
IT WILL REMAIN HUMID TONIGHT. A LIGHT SOUTHWEST SURFACE FLOW IS
ANTICIPATED AND MINIMUM TEMPERATURES SHOULD RANGE FROM THE UPPER 60S
IN THE FAR NORTH TO THE LOWER AND MIDDLE 70S ELSEWHERE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THIS EVENING/...
A MID LEVEL IMPULSE IS FORECAST TO PASS OVERHEAD ON THURSDAY
MORNING. A FRONTAL BOUNDARY IS EXPECTED TO APPROACH SLOWLY FROM
THE WEST THROUGH THE DAY. THE COMBINATION OF THE TWO FEATURES WILL
BRING A BETTER CHANCE FOR PRECIPITATION ON THURSDAY THAN WE
EXPERIENCED TODAY. PRECIPITABLE WATER VALUES SHOULD REMAIN MOSTLY
IN THE 1.5 TO 2.0 INCH RANGE SO LOCALLY MODERATE TO HEAVY RAINFALL
IS POSSIBLE.
THE SOUTHWEST SURFACE FLOW IS FORECAST TO CONTINUE FOR MOST OF THE
DAY AND TEMPERATURES SHOULD RISE INTO THE 80S AT MOST LOCATIONS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
A SURFACE LOW PRESSURE SYSTEM MOVING THROUGH EASTERN CANADA WILL
CONTINUE TO SLOWLY PULL A COLD FRONT THROUGH OUR AREA THURSDAY
NIGHT. THE FRONT WILL THEN STALL JUST OFF TO OUR SOUTH AND EAST
AND DISSIPATE THROUGH THE WEEKEND. AN AREA OF HIGH PRESSURE WILL
MOVE INTO THE REGION BEHIND THE DEPARTING FRONT OVER THE WEEKEND.
THIS HIGH GETS SQUEEZED AROUND OUR AREA AND GETS ABSORBED INTO THE
BERMUDA HIGH PRESSURE SITTING OVER THE WESTERN ATLANTIC. THE
BERMUDA HIGH WILL RETROGRADE TOWARD THE EAST COAST THROUGH EARLY
NEXT WEEK. IN THE MID LEVELS, A WAVE FORMS ALONG THE STALLED
BOUNDARY AND MOVES THROUGH THE REGION THURSDAY NIGHT INTO FRIDAY.
A MID LEVEL TROUGH FOLLOWS BEHIND THIS WAVE AND ENTERS OUR AREA
FRIDAY NIGHT. THIS WAVE EVENTUALLY GETS CUT OFF FROM THE MID LEVEL
FLOW AND REMAINS CENTERED ACROSS NEW ENGLAND. SEVERAL IMPULSES
WILL ROTATE AROUND THIS CUT OFF MID LEVEL LOW AND MOVE THROUGH OUR
AREA THROUGH THE WEEKEND. THE CUT OFF LOW GRADUALLY PUSHES TO THE
SOUTHWEST EARLY NEXT WEEK.
SHOWERS AND THUNDERSTORMS WILL REMAIN POSSIBLE THROUGH MUCH OF THE
EXTENDED PERIOD. SHOWERS AND THUNDERSTORMS WILL GRADUALLY MOVE OFF
TO THE SOUTH AND EAST AS THE FRONT PUSHES THROUGH AND THEN WE CAN
EXPECT TO DRY OUT A BIT EARLY ON FRIDAY. WITH THE LOW CUTTING OFF IN
THE MID LEVELS, WE ARE NOT ABLE TO SEE ANY KIND OF EXTENDED PERIOD
OF DRY WEATHER AND ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS
WILL CONTINUE TO BE MENTIONED EVERY DAY.
TEMPERATURES WILL BE CLOSER TO NORMAL THROUGH THE PERIOD WITH HIGHS
IN THE 80S AND LOWS IN THE 60S TO LOWER 70S. ONE GOOD ITEM OF NOTE
IS SLIGHTLY LOWER DEW POINTS WHICH WILL HELP IT TO FEEL A BIT LESS
HUMID THAN IT HAS OF LATE. AS WE NEAR THE LATER PART OF THE
EXTENDED, TEMPERATURES WILL ONCE AGAIN REACH INTO THE LOWER 90S WITH
DEWPOINTS RISING. EXPECT IT TO BECOME PROGRESSIVELY MORE HUMID
TOWARD THE END OF THE PERIOD.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
VFR CONDITIONS WILL LIKELY CONTINUE INTO THE FIRST HALF OF THE
NIGHT. WHILE THERE IS A CHANCE OF SHOWERS AND THUNDERSTORMS IN OUR
REGION INTO THIS EVENING, IT APPEARS AS THOUGH MOST LOCATIONS WILL
REMAIN RAIN-FREE. THE BEST CHCS ARE FOR THE NWRN TAF SITES. THE
MOISTURE IN THE ATMOSPHERE MAY RESULT IN THE DEVELOPMENT OF MVFR
CEILINGS AND VISIBILITY VALUES FOR LATE TONIGHT. SHOWERS AND
SCATTERED THUNDERSTORMS ARE ANTICIPATED FOR THURSDAY AS A SLOW
MOVING FRONTAL BOUNDARY APPROACHES FROM THE WEST. CONDITIONS WILL
LIKELY BE VARIABLE ON THURSDAY. DECIDED TO PUT IN A PROB30 FOR
THUNDER THU AFTN WITH THE CDFNT COMING THRU.
THE WIND SHOULD REMAIN FROM THE WEST AND SOUTHWEST INTO THIS EVENING
WITH SPEEDS AROUND 10 KNOTS AND GUSTS NEAR 20 KNOTS. WIND SPEEDS
WILL LIKELY DROP INTO THE 4 TO 8 KNOT RANGE AFTER DARK WITH SOME
LOCATIONS BECOMING LIGHT AND VARIABLE. A SOUTHWEST WIND AT 10 KNOTS
OR LESS IS ANTICIPATED FOR THURSDAY. THE WIND WILL SHIFT MORE NWLY
BEHIND THE CFP.
OUTLOOK...
THURSDAY NIGHT...SHOWERS AND THUNDERSTORMS ARE EXPECTED TO AFFECT
THE TERMINALS AS A COLD FRONT MOVES THROUGH THE AREA. LOCAL MVFR OR
LOWER CONDITIONS WILL OCCUR IN ANY STORMS. SOME THUNDERSTORMS COULD
PRODUCE LOCALLY GUSTY WINDS.
FRIDAY...MAINLY VFR CONDITIONS EXPECTED. ISOLATED SHOWERS AND
THUNDERSTORMS POSSIBLE, MAINLY TO THE SOUTH AND EAST OF KPHL.
SATURDAY THROUGH MONDAY...MAINLY VFR CONDITIONS EXPECTED. ISOLATED
TO SCATTERED SHOWERS AND THUNDERSTORMS ARE ANTICIPATED, ESPECIALLY
IN THE AFTERNOON AND EVENING. LOCAL MVFR OR LOWER CONDITIONS WILL
OCCUR IN ANY STORMS.
&&
.MARINE...
A SLOW MOVING FRONTAL BOUNDARY WILL APPROACH FROM THE WEST DURING
TONIGHT AND THURSDAY. WIND SPEEDS AND WAVE HEIGHTS WILL REMAIN BELOW
THE SMALL CRAFT ADVISORY CRITERIA. THERE IS A LOW CHANCE OF SHOWERS
AND THUNDERSTORMS INTO THIS EVENING. THERE IS A GREATER CHANCE FOR
SHOWERS AND THUNDERSTORMS ON THURSDAY.
OUTLOOK...
SUB-ADVISORY CONDITIONS ARE EXPECTED ON THE AREA WATERS THROUGH THE
PERIOD. A COLD FRONT WILL MOVE THROUGH THE AREA WATERS THURSDAY
AND THURSDAY NIGHT AND BRIEF TIGHTENING OF THE PRESSURE GRADIENT
WILL OCCUR. HOWEVER, WINDS AND WAVES ARE EXPECTED TO REMAIN BELOW
SMALL CRAFT ADVISORY CRITERIA. THE GRADIENT THEN WEAKENS BEHIND
THE FRONT. THE FRONT STALLS TO THE SOUTH AND EAST OF THE AREA AND
WILL DISSIPATE OVER THE WEEKEND, KEEPING A RELATIVELY WEAK
GRADIENT ACROSS THE AREA WATERS THROUGH EARLY NEXT WEEK.
SHOWERS AND THUNDERSTORMS ARE EXPECTED TO MOVE THROUGH THE REGION
OVER THE NEXT SEVERAL DAYS AND MAY CAUSE GUSTY WINDS TO OCCUR OVER
THE WATERS, WITH WINDS NEARING SPECIAL MARINE WARNING CRITERIA.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MEOLA
NEAR TERM...IOVINO/KLINE/NIERENBERG
SHORT TERM...IOVINO
LONG TERM...MEOLA
AVIATION...IOVINO/NIERENBERG/MEOLA
MARINE...IOVINO/MEOLA
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
230 AM EDT THU Jul 11 2013
.NEAR TERM [Today]...
The 03 UTC regional surface analysis showed very weak pressure
pattern across the Southeast, which is common this time of year.
Much of the Southeast was under the influence of the western
periphery of the Atlantic subtropical ridge, interrupted with
several spot lows/highs and outflow boundaries. There was a large
MCS propagating southward across northern AL, but all of the latest
Convection Allowing Models (CAM), including the HRRR, forecast this
system to miss our forecast area just to our west later this
morning. Vapor imagery and upper air data showed a developing weak
trough over much of the eastern CONUS.
Today`s forecast is a bit tricky. The large scale pattern (the
upper level trough, daytime heating, and ample deep layer moisture)
suggests that rain is likely, which is what the MOS consensus shows.
However, the some of the 12 & 18 UTC CAM runs concentrate the rain
over fairly limited areas in FL, perhaps due to too much high clouds
and boundary layer turnover from the MCS currently tracking
southward. Our PoP forecast is a hedge between these different
possibilities, with a PoP in the 50 to 60% range across much of our
forecast area. The expected clouds and convection should keep high
temperatures a few degrees below climatology.
Although the large scale environmental wind field will be weak
today, there will be considerable boundary layer moisture which
could result in SBCAPE values exceeding 2500 J/KG this afternoon.
Given the upstream MCS development observed already, it`s not
unreasonable to anticipate at least some multi-cell organization
and/or a few pulse strong/severe storms over our forecast area. The
probability of a severe storm within 25 miles of a point is only 5%,
which is double that of climatology but still lower than the 15-30%
associated with a "Slight Risk".
&&
.SHORT TERM [Tonight through Saturday]...
An upper trough will deepen down the Atlantic seaboard with a low
closing off over the eastern Great Lakes by 12z Friday. The digging
trough will drive deep layer moisture and a surface cold front into
our CWA. Deep layer ridging off the northeast CONUS will build
westward into New England Saturday with the upper low retrograding
into the Ohio Valley. Locally the front is forecast to stall over
our CWA and a weak wave may develop on the boundary over or just
south of the panhandle on Saturday. Forecast PW`s through the period
are at or above 2". This will all lead to unsettled weather
conditions with above seasonal PoPs and the threat for heavy
rainfall on grounds that are at or near saturated from recent rains.
Max temps will be held just under climo with the increased cloud
cover and convection.
&&
.LONG TERM [Saturday night through Wednesday]...
Unsettled conditions will continue through a large portion of the
long term with near to above climo PoPs. The forecast pattern is
rather unusual with both the 10/00z ECMWF and 10/12z GFS showing
an upper level low retrograding southwestward from the northeast
states down to the Gulf coast. There are some detail differences
in the models, but both models signal an overall wet pattern
continuing. Near to slightly below average high temperatures are
forecast given the expected cloud cover.
&&
.AVIATION [Through 06 UTC Friday]...
The 00 UTC MOS consensus is strangely optimistic for this morning,
while the 02 UTC High Resolution Rapid Refresh (HRRR) run forecasts
widespread LIFR-VLIFR cigs until mid morning. Given that a few sites
were already showing SCT-BKN 400 ft cigs at 06 UTC, we went more
with the HRRR idea of low cigs. The cigs will lift to VFR late
morning or early afternoon, followed by scattered to numerous TSRA.
&&
.MARINE...
Winds and seas will be low as the marine area remains at the
western periphery of the subtropical Atlantic ridge. This portion of
the ridge will erode as a weakening cold front approaches and stalls
over or just north of the waters on Friday. A weak surface low may
development on the frontal boundary late Friday and move off to the
west or northwest over the weekend. If this low develops, winds and
seas will be a bit tricky to forecast but conditions should stay
below headline criteria.
&&
.FIRE WEATHER...
No fire weather concerns.
&&
.HYDROLOGY...
We appear to be headed into another stretch of wet weather over
the next 7-10 days based on the latest model guidance. Unlike the
round of heavy rainfall in early July, there is not much agreement
yet on a particular area where the heaviest rain totals may be
focused. Therefore, the outlook (in terms of hydrology) is just
for heavy rainfall and the possibility of some flooding issues
again. The 7-day WPC QPF calls for widespread 2-3 inch totals over
our entire area, which is very close to model ensemble mean
values. Of course, there are likely to be localized values well in
excess of that.
Even taking the 2-3 inch rain forecast literally (which is pretty
close to the majority of the NAEFS members) and applying it to
MMEFS forecasts for river points in our area does produce some
chance of flooding on a few of the rivers.
Rivers Most At-Risk For Continued / Developing Flooding July 10-20
------------------------------------------------------------------
Aucilla River, St. Marks River, Withlacoochee River near Valdosta,
the Choctawhatchee River (particularly lower portions), and the
Apalachicola River. Only change since this afternoon is that due
to heavy rains, Aucilla back to minor flooding.
Of course, given high flows on many rivers due
to recent rainfall, it would be impossible to totally rule out
rises and/or flooding on any of our area rivers. Where localized
heavy rainfall sets up will be the main concern - as it will have
the potential to produce flash flooding, as well as more
considerable rises on rivers. After several days of rain, the more
at-risk areas may be easier to pinpoint. The bottom line is that
those with interests along area rivers, streams, and creeks, and
in flood-prone areas should keep a close eye on forecasts over the
next 7-10 days.
&&
.PRELIMINARY POINT TEMPS/POPS...
TALLAHASSEE 88 72 90 72 89 / 60 50 70 50 60
PANAMA CITY 85 75 87 74 89 / 60 50 70 50 60
DOTHAN 88 72 90 72 89 / 50 50 60 30 60
ALBANY 89 72 90 72 90 / 50 50 70 40 60
VALDOSTA 89 71 89 70 88 / 50 50 70 50 60
CROSS CITY 89 71 89 71 90 / 60 40 70 60 60
APALACHICOLA 85 75 85 72 87 / 60 50 70 50 60
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
Near Term...Fournier
Short Term...Barry
Marine...Barry
Aviation/Fire Weather...Fournier
Long Term...DVD
Hydrology...Block/Lamers
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
401 AM CDT THU JUL 11 2013
...UPDATED FOR SHORT TERM DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 358 AM CDT THU JUL 11 2013
THE SURFACE FRONT THAT WAS LOCATED ACROSS SOUTHWEST KANSAS
WEDNESDAY AFTERNOON WAS GETTING ANOTHER BOOST SOUTHWARD FROM
OVERNIGHT THUNDERSTORM OUTFLOW. UPPER LEVEL RIDGING WILL BE EDGING
BACK OVER THE CENTRAL PLAINS OVER THE NEXT 24 TO 36 HRS. HOWEVER,
THE EFFECTIVE FRONTAL BOUNDARY MAY BE SLOW TO MOVE BACK TO THE NORTH
TODAY. INSTEAD OF MORE OF A SOUTHERLY WIND PER THE NAM MODEL, WITH
TEMPERATURES REACHING 100-102F, MORE OF A SOUTHEASTERLY UPSLOPE WIND
MAY SERVE TO KEEP TEMPERATURES FROM REACHING 100F PER RAP MODEL
(WITH MID TO UPPER 90S MORE LIKELY. IN ADDITION, ANY ONGOING
CONVECTION OVER SOUTH CENTRAL AND CENTRAL KANSAS THIS MORNING COULD
HELP KEEP TEMPERATURES COOLER ALONG A MEDICINE LODGE TO HAYS
CORRIDOR THIS AFTERNOON DUE TO OUTFLOW FROM THE SOUTHEAST. KEEP
IN MIND THAT LEE TROUGHING WILL BE STRENGTENING IN THE LEE OF THE
ROCKIES THIS AFTERNOON IN REPONSE TO STRONG SOUTHWEST MID LEVEL
FLOW ACROSS THE NORTHERN ROCKIES. THIS WOULD TEND TO PROMOTE
MORE OF A SOUTH WIND AND HOTTER TEMPERATURES FOR TODAY. SO DESPITE
THE OUTFLOW, I WOULD NOT BE SURPRISED IF TEMPERATURES ROSE TO OVER
100 DEGREES IN DODGE CITY BY THIS AFTERNOON--HENCE THE FORECAST
UNCERTAINTY. BY LATE AFTERNOON, A CORRIDOR OF 2000 J/KG SURFACE
BASED CAPE WILL BE SITUATED FROM DODGE CITY TO DIGHTON AND SCOTT
CITY. ISOLATED THUNDERSTORMS CANNOT BE RULED OUT. UPPER LEVEL WINDS
WILL BE QUITE A BIT WEAKER TODAY THAN ON WEDNESDAY ALONG THE
INTERSTATE 70 CORRIDOR SO THAT ANY HAIL WOULD BE QUARTER SIZE OR
SMALLER. ANY CONVECTION THAT DEVELOPS LATE THIS AFTERNOON SHOULD
WEAKEN THIS EVENING WITH THE LOSS OF DAYTIME HEATING GIVEN THE LACK
OF UPPER LEVEL SUPPORT. TEMPERATURES TONIGHT WILL BE HELD UP BY
SOUTH WINDS, WITH LOWS IN THE LOWER TO MID 70S.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 254 AM CDT THU JUL 11 2013
A RETURN TO HOT AND DRY CONDITIONS IS FORECAST FOR FRIDAY SATURDAY
AND POSSIBLY BEYOND, AS AN UPPER HIGH PRESSURE RIDGE ROTATES INTO THE
HIGH PLAINS REGION AND BECOMES STATIONARY FOR A FEW DAYS. FORECAST
MODELS DO SHOW CONSIDERABLE SPREAD FROM AROUND 100 DEGREES INTO THE
MID 100`S BOTH DAY AS THE WARM BOUNDARY LAYER PLUME OVERSPREAD THE
AREA WITH 27-30 DEGREES C 850 MB AIR. IF THE WARMEST OF FORECAST
SOLUTIONS VERIFY ACROSS CENTRAL KANSAS, DANGEROUS HEAT INDICES COULD
BE ACHIEVED IN THE AFTERNOON. THE PATTERN BECOMES MORE FLATTENED
AFTER FRIDAY, AND JUST HOW WARM THE HIGHS GET IN THE AFTERNOON ARE
LESS CLEAR. BY MONDAY, THE ECMWF SHOWS A FRONT IN THE VICINITY OF
NORTHWEST KANSAS AND SW NEBRASKA. THAT KIND OF PATTERN WOULD
RELEGATE STORMS TO THE FRONT WITH A LACK OF STEERING FLOW. A RESULT
OF THE NEARLY STATIONARY UPPER HIGH WILL BE SURFACE WINDS BECOMING
MORE LIGHT AND VARIABLE WITH TIME AS THE SUBSIDENCE INDUCED SURFACE
HIGH MAINTAINS INCREASING HIGH PRESSURE FROM THE NORTHERN PLAINS.
LIGHT AND VARIABLE OR LIGHT EASTERLY FLOW WOULD SUPPORT NOT AS HOT
TEMPERATURES IN THE MID TO UPPER 90S AND LOWER FREQUENCIES OF 100
DEGREE AND HIGH READINGS. ISOLATED ELEVATED THUNDERSTORMS CAN`T BE
RULED OUT COMPLETELY MID TO LATE WEEK AS MODELS SHOW A SUBTLE SIGNAL
OF MID LEVEL MOISTURE SPREADING NORTHWARD ON THE BACK SIDES OF THE
UPPER HIGH PRESSURE. CONFIDENCE IS TOO LOW HOWEVER TO RAISE THE
CURRENT ALLBLEND APPROACH OF SINGLE DIGIT PRECIPITATION
PROBABILITIES DURING THIS TIMEFRAME. .
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1244 AM CDT THU JUL 11 2013
IN THE WAKE OF AN OUTFLOW BOUNDARY FROM THUNDERSTORMS IN FAR
WESTERN KANSAS, WINDS AT GCK/DDC WILL BE WESTERLY BETWEEN 06-8Z, THEN
BECOME LIGHT AND VARIABLE OVERNIGHT BEFORE SWITCHING TO THE
SOUTHEAST/SOUTH AT 15 KTS BY 15-17Z. VFR CONDITIONS SHOULD PREVAIL
IN THE ABSENCE OF THUNDERSTORMS AT THE TAF SITES.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 98 73 104 74 / 10 10 0 0
GCK 97 73 104 73 / 20 20 0 0
EHA 99 72 103 71 / 10 10 0 0
LBL 98 72 104 73 / 10 10 0 0
HYS 96 73 104 75 / 20 20 0 0
P28 99 74 102 75 / 20 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...FINCH
LONG TERM...RUSSELL
AVIATION...FINCH
AREA FORECAST DISCUSSION...CORRECTED
NWS WICHITA KS
400 AM CDT THU JUL 11 2013
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 400 AM CDT THU JUL 11 2013
TODAY:
(+)TSRA CLUSTER CONTINUES OVER SW NEBRASKA/NW KS BORDER FROM ~KMCK SE
OVER DECATUR & NORTON COUNTIES. ANOTHER (+)TSRA THAT DEVELOPED OVER
ERN OSBORNE COUNTY IS STATIONARY. TSRA BEING SUSTAINED BY STRONG DEEP
ISENTROPIC ASCENT FROM 305-315K LAYER INDUCED BY BROAD HIGH PRESSURE
COVERING MOST OF UPR MS VALLEY & WEAK LOW PRESSURE SITUATED NEAR CO/KS
BORDER...FROM WHICH A WEAK NEARLY STATIONARY FRONT EXTENDS SE ACROSS
SW KS TO NRN OK. WELL-DEFINED RICH LWR-DECK MOISTURE AXIS IS ORIENTED
IN NW-SE MANNER ALONG & JUST NE OF THE BOUNDARY TO ALONG THE W/SW
CORRIDOR OF KICT COUNTRY. GREATEST CHANCES FOR TSRA TO THEREFORE OCCUR
OVER WRN HALF OF KICT COUNTRY THIS MORNING. HRRR DEPICTING A SIMILAR
PATTERN & AS SUCH HAVE INCREASED POPS TO 35-40% OVER THAT PART OF
CNTRL KS W OF I-135. AS LWR-DECK TROFFING GETS BETTER ESTABLISHED LWR
DECK FLOW TO BECOME MORE SLY WHICH WOULD REALIGN LWR-DECK MOISTURE
AXIS TO N-S ORIENTATION. WITH STRONG MASSIVE MID-UPR HIGH INCREASING
DOMINANCE FROM THE SRN TOWARD THE NRN PLAINS THE RESULTING INCREASED
SUBSIDENCE WOULD INHIBIT FURTHER TSRA DEVELOPMENT THIS AFTERNOON.
THE ALREADY STRONG MASSIVE HIGH PRESSURE BECOMES EVEN MORE SO OVER THE
NEXT 3 DAYS & WITH LWR-DECK TROFFING INCRESING OVER THE WRN PLAINS THE
FURNACE WILL REMAIN TURNED UP THRU SATURDAY. HIGHS ~100F ARE LIKELY
ALONG THE WRN CORRIDOR FRI & SAT WHERE HEAT INDICES ~105F ARE POSSIBLE.
AS SUCH A HEAT ADVISORY MAY BE REQUIRED...ESPECIALLY FRI. STAY TUNED.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 355 AM CDT THU JUL 11 2013
TYPICAL MID-SUMMER STILL ANTICIPATED THROUGHOUT THESE PERIODS. HOWEVER
MID-RANGE MODELS (MORE SO THE GFS) DEPICT A MID-UPR LOW PRESSURE AREA
RETROGRADING ACROSS THE MID-MS VALLEY TOWARD...THEN ACROSS...THE MO/KS
BORDER ON MON. FOR NOW HAVE DRY FORECAST INTACT BUT THE BEHAVIOR OF THE
UNORTHODOX LOW WILL REQUIRE INCREASED ATTENTION LATER THIS WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1142 PM CDT WED JUL 10 2013
VFR CONDITIONS WILL CONTINUE ACROSS THE FORECAST AREA FOR THE NEXT
24 HOURS...CONVECTION THAT PREVIOUSLY FIRED ALONG THE THE MAIN SFC
FRONTAL BOUNDARY OVER NRN OK HAS ENDED.
CONVECTION ACROSS EXTREME WRN KS COULD VENTURE E-SE AS THE OVERNIGHT
PROGRESSES...BUT THINK MOST OF THIS CONVECTION WILL WANE AS IT
APPROACHES THE AREA. ALSO THINK THAT ANY CONVECTION THAT SURVIVES
THIS FAR EAST WILL DIVE SOUTHEAST AND MISS THE SOUTH CEN KS TAF
SITES OF KICT/KHUT.
A SMALL CONCERN ABOUT THE SCT CONVECTION CURRENTLY DEVELOPING OVER
SW NEB. FLOW PATTERN WOULD TAKE THIS CONVECTION TOWARDS CEN KS LATE
TONIGHT OR EARLY THU MORNING...IF IT CAN HOLD TOGETHER. NOT SURE
HOW LONG THIS CONVECTION WILL LAST AS IT MAKES PROGRESS TO THE
SOUTHEAST...AS LOW LEVEL MOISTURE SUPPORT ISNT THAT IMPRESSIVE...AND
THIS CONVECTION WILL MOVE INTO THE A MORE STABLE ATMOSPHERE AS IT
MOVES SOUTHEAST. SO WILL NOT ADD ANY TSRA CHANCE INTO THE KRSL OR
KSLN TAFS EARLY ON MON FOR NOW. SHORT RANGE HIGH-RES MODELS BLOW
THIS SCATTERED CONVECTION INTO A COMPLEX OF STORMS AND DROP IT SOUTH
ACROSS THE FORECAST AREA FOR THU AM. THINK THIS IS OVERDONE FOR
REASONS MENTIONED ABOVE.
KETCHAM
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 97 72 99 77 / 30 0 0 0
HUTCHINSON 96 72 100 77 / 40 0 0 0
NEWTON 94 71 97 76 / 30 0 0 0
ELDORADO 93 71 97 75 / 20 0 0 0
WINFIELD-KWLD 96 73 99 76 / 30 0 0 0
RUSSELL 95 72 102 77 / 40 10 0 0
GREAT BEND 96 73 102 77 / 40 10 0 0
SALINA 93 72 101 77 / 30 10 0 0
MCPHERSON 94 72 100 77 / 40 0 0 0
COFFEYVILLE 92 71 97 73 / 10 0 0 0
CHANUTE 89 69 95 71 / 10 0 0 0
IOLA 90 68 94 71 / 10 0 0 0
PARSONS-KPPF 91 70 95 72 / 10 0 0 0
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
ES
*CORRECTED TO INCLUDE POTENTIAL FOR HEAT ADVISORY ISSUANCE FOR FRI.*
AREA FORECAST DISCUSSION
NWS WICHITA KS
354 AM CDT THU JUL 11 2013
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 355 AM CDT THU JUL 11 2013
TODAY:
(+)TSRA CLUSTER CONTINUES OVER SW NEBRASKA/NW KS BORDER FROM ~KMCK SE
OVER DECATUR & NORTON COUNTIES. ANOTHER (+)TSRA THAT DEVELOPED OVER
ERN OSBORNE COUNTY IS STATIONARY. TSRA BEING SUSTAINED BY STRONG DEEP
ISENTROPIC ASCENT FROM 305-315K LAYER INDUCED BY BROAD HIGH PRESSURE
COVERING MOST OF UPR MS VALLEY & WEAK LOW PRESSURE SITUATED NEAR CO/KS
BORDER...FROM WHICH A WEAK NEARLY STATIONARY FRONT EXTENDS SE ACROSS
SW KS TO NRN OK. WELL-DEFINED RICH LWR-DECK MOISTURE AXIS IS ORIENTED
IN NW-SE MANNER ALONG & JUST NE OF THE BOUNDARY TO ALONG THE W/SW
CORRIDOR OF KICT COUNTRY. GREATEST CHANCES FOR TSRA TO THEREFORE OCCUR
OVER WRN HALF OF KICT COUNTRY THIS MORNING. HRRR DEPICTING A SIMILAR
PATTERN & AS SUCH HAVE INCREASED POPS TO 35-40% OVER THAT PART OF
CNTRL KS W OF I-135. AS LWR-DECK TROFFING GETS BETTER ESTABLISHED LWR
DECK FLOW TO BECOME MORE SLY WHICH WOULD REALIGN LWR-DECK MOISTURE
AXIS TO N-S ORIENTATION. WITH STRONG MASSIVE MID-UPR HIGH INCREASING
DOMINANCE FROM THE SRN TOWARD THE NRN PLAINS THE RESULTING INCREASED
SUBSIDENCE WOULD INHIBIT FURTHER TSRA DEVELOPMENT THIS AFTERNOON.
THE ALREADY STRONG MASSIVE HIGH PRESSURE BECOMES EVEN MORE SO OVER THE
NEXT 3 DAYS & WITH LWR-DECK TROFFING INCRESING OVER THE WRN PLAINS THE
FURNACE WILL REMAIN TURNED UP THRU SATURDAY. HIGHS ~100F ARE LIKELY
ALONG THE WRN CORRIDOR.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 355 AM CDT THU JUL 11 2013
TYPICAL MID-SUMMER STILL ANTICIPATED THROUGHOUT THESE PERIODS. HOWEVER
MID-RANGE MODELS (MORE SO THE GFS) DEPICT A MID-UPR LOW PRESSURE AREA
RETROGRADING ACROSS THE MID-MS VALLEY TOWARD...THEN ACROSS...THE MO/KS
BORDER ON MON. FOR NOW HAVE DRY FORECAST INTACT BUT THE BEHAVIOR OF THE
UNORTHODOX LOW WILL REQUIRE INCREASED ATTENTION LATER THIS WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1142 PM CDT WED JUL 10 2013
VFR CONDITIONS WILL CONTINUE ACROSS THE FORECAST AREA FOR THE NEXT
24 HOURS...CONVECTION THAT PREVIOUSLY FIRED ALONG THE THE MAIN SFC
FRONTAL BOUNDARY OVER NRN OK HAS ENDED.
CONVECTION ACROSS EXTREME WRN KS COULD VENTURE E-SE AS THE OVERNIGHT
PROGRESSES...BUT THINK MOST OF THIS CONVECTION WILL WANE AS IT
APPROACHES THE AREA. ALSO THINK THAT ANY CONVECTION THAT SURVIVES
THIS FAR EAST WILL DIVE SOUTHEAST AND MISS THE SOUTH CEN KS TAF
SITES OF KICT/KHUT.
A SMALL CONCERN ABOUT THE SCT CONVECTION CURRENTLY DEVELOPING OVER
SW NEB. FLOW PATTERN WOULD TAKE THIS CONVECTION TOWARDS CEN KS LATE
TONIGHT OR EARLY THU MORNING...IF IT CAN HOLD TOGETHER. NOT SURE
HOW LONG THIS CONVECTION WILL LAST AS IT MAKES PROGRESS TO THE
SOUTHEAST...AS LOW LEVEL MOISTURE SUPPORT ISNT THAT IMPRESSIVE...AND
THIS CONVECTION WILL MOVE INTO THE A MORE STABLE ATMOSPHERE AS IT
MOVES SOUTHEAST. SO WILL NOT ADD ANY TSRA CHANCE INTO THE KRSL OR
KSLN TAFS EARLY ON MON FOR NOW. SHORT RANGE HIGH-RES MODELS BLOW
THIS SCATTERED CONVECTION INTO A COMPLEX OF STORMS AND DROP IT SOUTH
ACROSS THE FORECAST AREA FOR THU AM. THINK THIS IS OVERDONE FOR
REASONS MENTIONED ABOVE.
KETCHAM
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 97 72 99 77 / 30 0 0 0
HUTCHINSON 96 72 100 77 / 40 0 0 0
NEWTON 94 71 97 76 / 30 0 0 0
ELDORADO 93 71 97 75 / 20 0 0 0
WINFIELD-KWLD 96 73 99 76 / 30 0 0 0
RUSSELL 95 72 102 77 / 40 10 0 0
GREAT BEND 96 73 102 77 / 40 10 0 0
SALINA 93 72 101 77 / 30 10 0 0
MCPHERSON 94 72 100 77 / 40 0 0 0
COFFEYVILLE 92 71 97 73 / 10 0 0 0
CHANUTE 89 69 95 71 / 10 0 0 0
IOLA 90 68 94 71 / 10 0 0 0
PARSONS-KPPF 91 70 95 72 / 10 0 0 0
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
ES
AREA FORECAST DISCUSSION
NWS JACKSON KY
218 AM EDT THU JUL 11 2013
.UPDATE...
ISSUED AT 217 AM EDT THU JUL 11 2013
DRY AIR CONTINUES TO FILTER IN ACROSS THE REGION...AND WITH LLVL
INVERSION IN PLACE...ANY PRECIP NEAR THE REGION HAS ALL BUT DIED OUT.
THIS INCLUDES THE LINE OF PRECIP THAT WAS RIDING ALONG THE FRONT TO
OUR NORTH EARLIER IN THE EVENING. AS A RESULT...BUMPED POPS DOWN
TONIGHT AND THROUGH MUCH OF THE DAY TOMORROW. ANY CONVECTION THAT
DEVELOPS WILL BE ISOLATED ACROSS MUCH OF THE REGION...WITH THE BEST
CHANCES OF SCT CONVECTION IN THE FAR SE AS THE SURFACE FRONT GOES
THROUGH THIS MORNING/EARLY AFTERNOON /AIDED BY SOME DAYTIME HEATING/.
UPDATE ISSUED AT 945 PM EDT WED JUL 10 2013
THUNDERSTORMS ARE OVER AND SHOWERS ARE DIMINISHING. PCPN HAS BECOME
MORE SCT IN NATURE AND WILL REDUCE POPS FOR THE OVERNIGHT. COLD FRONT
STILL PRESSING TO THE SE ACROSS THE OHIO RIVER BUT IT IS INDICATED BY
A THIN LINE OF WIDELY DISPERSED CONVECTION. TEMPS ON TRACK BUT THE
FOG IS MORE WIDESPREAD THAN PREVIOUS FCST AND IS EVEN SOME LOW
STRATUS AT JKL REDUCING CIG AND VSBY.
UPDATE ISSUED AT 710 PM EDT WED JUL 10 2013
THUNDERSTORMS HAVE DIMINISHED IN INTENSITY AND COVERAGE. HEAVY RAIN
IS OVER AND WILL ELIMINATE BOTH THE SVR THUNDERSTORM WATCH 407 AND
THE FLASH FLOOD WATCH.
UPDATE ISSUED AT 600 PM EDT WED JUL 10 2013
HAVE HAD ONLY 1 REPORT OF WIND DAMAGE SO FAR...AND SEVERE THREAT IS
DIMINISHING. WILL BE UPDATING NDFD FOR LATEST OBSERVATIONAL TRENDS
AND FOR CURRENT MOVEMENT OF SHOWERS AND THUNDERSTORMS ACROSS THE
FORECAST AREA. PLAN TO BEGIN TRIMMING COUNTIES FROM THE SEVERE
THUNDERSTORM WATCH ON THE WESTERN PART OF THE FORECAST AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 304 PM EDT WED JUL 10 2013
WILL ADD PIKE...LETCHER AND HARLAN COUNTY TO FLASH FLOOD WATCH.
WITH CONVECTION IN THESE AREAS ALREADY OCCURRING TODAY...THEY WILL BE
PRIMED FOR POTENTIAL FLASH FLOODING WITH ADDITIONAL ACTIVITY THIS
EVENING AND OVERNIGHT. COLD FRONT CURRENTLY IN NORTHWEST INDIANA WILL
BE ONLY SLOWLY PRESSING SOUTHEAST OVERNIGHT AND NOT CLEARING
SOUTHEAST KY UNTIL THURSDAY AFTERNOON. LATEST MODEL GUIDANCE AND
ESPECIALLY CURRENT RADAR TRENDS POINTING TOWARDS MULTIPLE ROUNDS OF
SHOWERS AND THUNDERSTORMS FROM LATE THIS AFTERNOON INTO TONIGHT.
PRECIPITABLE WATER AROUND 1.8 THIS AFTERNOON AND WILL NOT SEE MUCH
DECREASE UNTIL AFTER FRONTAL PASSAGE ON THURSDAY...AND THUNDERSTORMS
WILL CONTINUE TO BE CAPABLE OF PRODUCING VERY HEAVY RAIN.
CONSIDERABLE DESTABILIZATION HAS OCCURRED THIS AFTERNOON AND SEVERE
THREAT ALSO INCREASING...WITH SEVERE REPORTS ALREADY OCCURRING IN
CENTRAL KY. HRRR IS POINTING TOWARDS ACTIVITY OVER CENTRAL KY MERGING
INTO A BOWING LINE WHICH WOULD INCREASE SEVERE THREAT OVER SE KY
EARLY THIS EVENING.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 334 PM EDT WED JUL 10 2013
THERE IS DECENT AGREEMENT WITH THE VARIOUS MODELS HOWEVER THERE IS
SOME CONCERN WITH THE RESIDUAL UPPER TROUGH THAT DOES NOT WANT TO GO
AWAY. THE MODELS ARE SHOWING THE UPPER TROUGH INITIALLY MOVING TO
THE EAST. THIS WILL BRING SOME DRIER AND COOLER AIR TO THE AREA FOR
A WHILE...BUT THEN THE MODELS SHOW THE REMNANTS OF THE UPPER LOW OVER
OHIO ON SUNDAY. THE LOW THEN MEANDERS SOUTH OVER TIME. WITH ALL THE
SOLUTIONS...ALL THE FRONTS WILL STAY NORTH OF THE AREA AND EASTERN
KENTUCKY WILL JUST BE GENERAL AIR MASS CONVECTIVE ACTIVITY AND WILL
BE FAIRLY WARM AND HUMID. THE CONFIDENCE TENDS TO GO DOWN AFTER
SUNDAY FOR THE REST OF THE PERIOD BECAUSE IT WILL BE SO HARD TO TELL
WHERE THE AREAS OF ORGANIZED CONVECTION WILL BE. IN GENERAL WENT WITH
A MODEL BLEND...HOWEVER DID AN EXTRA NUDGE TOWARD THE ECMWF. FOR
TEMPERATURES...WENT A BIT COOLER THAN THE MODEL BLEND FOR THE SUNDAY
THROUGH WEDNESDAY TIME FRAME STAYING CLOSER TO THE ECMWF RAW OUTPUT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 217 AM EDT THU JUL 11 2013
A LINE OF SHOWERS AND THUNDERSTORMS MOVED THROUGH THE AREA YESTERDAY
AFTERNOON/EVENING AHEAD OF AN APPROACHING SURFACE COLD FRONT...BEFORE
EXITING THE REGION BY LATE EVENING. AS SUCH...DRY AIR HAS NOW
FILTERED IN BEHIND THE CONVECTION...BUT A LLVL INVERSION THAT HAS
DEVELOPED HAS TRAPPED A LARGE AMOUNT OF MOISTURE NEAR THE SURFACE.
THIS HAS CAUSED FOG TO DEVELOP AND AFFECT MUCH OF THE
REGION...INCLUDING ALL THREE TAF SITES...CAUSING THEM TO FALL BELOW
AIRPORT MINIMUMS. FORECAST SOUNDINGS POINT AT THIS FOG STICKING
AROUND THROUGH MORNING...THEN AS SURFACE FRONT APPROACHES...BEST
MOISTURE WILL LIFT FROM THE SURFACE TO CREATE A LLVL STRATUS DECK AND
THEN EVENTUALLY A BROKEN CU DECK BEFORE IT SCATTERS OFF IN THE
EVENING. DRY AIRMASS IN PLACE SHOULD PREVENT ANY REDEVELOPMENT OF FOG
OVERNIGHT TOMROROW NIGHT...THOUGH IF A SHOWER DOES IN FACT DEVELOP
AND COME IN CONTACT WITH A TAF SITE...MOISTURE LEFT OVER COULD MODIFY
THE LLVLS AND SOME PATCHY FOG COULD DEVELOP.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...SBH
LONG TERM...JJ
AVIATION...JMW
AREA FORECAST DISCUSSION
NWS BISMARCK ND
405 AM CDT THU JUL 11 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 405 AM CDT THU JUL 11 2013
CURRENTLY...SURFACE HIGH PRESSURE WAS OVER SOUTHERN MINNESOTA AND
IOWA WITH LOW PRESSURE IN THE LEE OF THE ROCKIES. SOUTH/SOUTHEAST
SURFACE WINDS ACROSS THE REGION WAS ALLOWING INCREASING LOW LEVEL
MOISTURE WITH DEWPOINTS IN THE UPPER 50S TO MID 60S. MESOANALYSIS
INDICATES A LOW LEVEL JET HAD DEVELOPED FROM THE SOUTHERN PLAINS
INTO THE WESTERN DAKOTAS. THE LEADING EDGE OF THE JET...WITH
INCREASING SOUTHEAST WINDS AND DEWPOINTS WAS PROVIDING ENOUGH LIFT
FOR MID-LEVEL CLOUD DEVELOPMENT SEEN ON SATELLITE PICS EXTENDING
FROM NEAR DICKINSON TO MOBRIDGE TO SOUTH CENTRAL SOUTH DAKOTA.
REGIONAL RADARS PICKING UP ON SMALL CELLS TRYING TO DEVELOP IN THIS
LINE IN SOUTH DAKOTA - IN THE PAST HOUR OR TWO THE SMALL CELLS BEGIN
TO DEVELOP AND THEN DISSIPATE. AFTER 2 AM A CELL NEAR PIERRE WAS
BECOMING MORE ROBUST WITH DBZ VALUES ABOVE 50. THE HRRR 1KM
REFLECTIVITY DEPICTED THIS CONVECTION - AND KEEPS MOST OF IT MAINLY
IN SOUTH DAKOTA THIS MORNING...BUT INDICATES THE POTENTIAL IN SOUTH
CENTRAL NORTH DAKOTA TOWARDS DAYBREAK. HIGH EFFECTIVE BULK SHEAR AND
1000-2000 J/KG CAPE IN SOUTHWESTERN NORTH DAKOTA...MID-LEVEL LAPSE
RATES ARE HIGHER IN SOUTH CENTRAL AND WESTERN SOUTH DAKOTA...BUT
POTENTIAL FOR SOME CELLS THIS MORNING - WILL ADD A MENTION OF SLIGHT
CHC OF THUNDERSTORMS THIS MORNING.
AS TIME GOES ON TODAY...THE MID LEVEL CAP IS FORECAST TO
STRENGTHEN...WITH H700 TEMPERATURES AS PER THE NAM RISING TO +10C IN
THE DEVILS LAKE/JAMES RIVER BASINS BY NOON...AND TO +14C IN THE FAR
SOUTHWEST. THIS CAP SHOULD ACT TO KEEP SKIES CLEAR AND FREE OF
CONVECTION DURING THE DAYTIME. MEANWHILE DEWPOINT TEMPERATURES IN
THE 60S TO NEAR 70 WILL MAKE FOR A VERY WARM/HOT AND HUMID DAY
ACROSS THE FORECAST AREA TODAY.
THIS EVENING...THE LEADING EDGE OF UPPER LEVEL SHORTWAVE ENERGY
REACHES THE WESTERN ND BORDER IN THE SOUTHWEST FLOW ALOFT. AT THE
SURFACE...IN RESPONSE THE LEE-SIDE LOW PRESSURE TROUGH MOVES/DEVELOPS
EASTWARD AND REACHES THE WESTERN DAKOTAS EARLY EVENING. THE QUESTION
IS WHETHER THE UPPER LEVEL SHORTWAVE ENERGY WILL DISTURB THE
MID-LEVEL THERMAL CAP TO ALLOW CONVECTION BY LATE AFTERNOON/EARLY
EVENING...OR WHETHER CONVECTION WILL BEGIN JUST BEFORE/AROUND SUNSET
WHEN THE MID-LEVEL CAP WOULD WEAKEN A BIT. FORECAST CAPE VALUES OF
1500-3000 J/KG AND 0-6KM BULK SHEAR ABOVE 45KTS THIS EVENING AND
LATE NIGHT WILL PROVIDE PLENTY OF INSTABILITY FOR THE MENTION OF
SEVERE THUNDERSTORM POSSIBILITIES. EASTERN MT/WY AND THE WESTERN
DAKOTAS ARE IN THE SPC DAY1 SLIGHT RISK FOR SEVERE THUNDERSTORMS.
KEPT THE CHANCE OF PRECIPITATION IN THE EVENING MAINLY IN THE WEST
AND NORTH CENTRAL...AND INCREASED CHANCES IN CENTRAL NORTH DAKOTA
AFTER MIDNIGHT TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 405 AM CDT THU JUL 11 2013
WE REMAIN IN A TYPICAL MID-SUMMER WEATHER PATTERN WITH THE UPPER
LEVEL JET STREAM NEAR THE NORTHERN PLAINS REGION THROUGH MUCH OF
THE LONG TERM FORECAST PERIOD...RESULTING IN PERIODS OF SHOWERS
AND THUNDERSTORMS FOR THE NEXT SEVERAL DAYS.
FRIDAY INTO FRIDAY NIGHT...SFC TROUGH BY 12Z FRIDAY WILL BE MOVING
EAST ACROSS CENTRAL NORTH DAKOTA. BY FRIDAY AFTERNOON...MODELS
POSITION THE SFC TROUGH FROM CENTRAL SOUTH DAKOTA NORTH-NORTHEAST
INTO NORTHEASTERN NORTH DAKOTA. THIS WILL PUT THE BEST CHANCES
FOR ACCUMULATING PRECIPITATION/STRONGER THUNDERSTORMS MAINLY EAST
OF HIGHWAY 83 WITH THE BETTER COVERAGE/CHANCES OVER THE JAMES
RIVER VALLEY INTO THE RED RIVER VALLEY AREA WITH MINIMAL
INSTABILITY OVER THE WESTERN HALF OF THE STATE THANKS TO DRY AIR
ADVECTION. MAINLY DRY OVER WEST AND CENTRAL NORTH DAKOTA FRIDAY
EVENING WITH WEAK SFC HIGH PRESSURE IN PLACE ACROSS THE CENTRAL
PART OF THE STATE. WE START TO SEE INCREASING CHANCES FOR
THUNDERSTORMS LATE FRIDAY NIGHT WEST WHERE ANOTHER AREA OF SURFACE
LOW PRESSURE ARRIVES FROM EASTERN MONTANA.
THIS SURFACE LOW...ALONG WITH MID LEVEL S/WV`S LIFTING NORTHEAST
THROUGH THE STATE...WILL BE THE FOCUS FOR DECENT THUNDERSTORM
CHANCES SATURDAY/SATURDAY NIGHT. STRONG TO SEVERE STORMS WILL BE
POSSIBLE GIVEN 1-2K J/KG OF MUCAPE AND 0-6KM SHEAR 35KTS OR
GREATER. THE DAY 3 SPC OUTLOOK HAS INCLUDED THE ENTIRE STATE OF ND
IN THE SLIGHT RISK FOR SEVERE WEATHER.
A QUIET PERIOD IS IN THE OFFING LATER SUNDAY THROUGH SUNDAY NIGHT
WITH HIGH PRESSURE BUILDING SOUTH ACROSS THE REGION. OPTED TO
MAINTAIN SLIGHT CHANCE POPS FOR NOW SUNDAY NIGHT IN CASE THE 00Z
GFS PROVES MORE CORRECT WHICH KEEPS HIGH PRESSURE MORE OVER
SOUTHERN CANADA. THE LAST FEW RUNS OF THE ECMWF BUILD THE SFC HIGH
OVER NORTH DAKOTA AND WOULD SUPPORT DRY WEATHER.
THE PARADE OF MID LEVEL WAVES CONTINUES...AND WILL MAINTAIN SOME
MENTION FOR THUNDERSTORMS THROUGH THE MIDDLE OF NEXT WEEK.
TEMPERATURES WILL AVERAGE NORMAL THROUGH THE PERIOD...WITH HIGHS
IN THE 80S TO LOW/MID 90S...AND LOWS MID 50S TO THE UPPER 60S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1243 AM CDT THU JUL 11 2013
MAINLY CLEAR SKIES FOR THIS TAF ISSUANCE. THE ONLY EXCEPTION IS A
TEMPO FROM 09Z-13Z FOR THE POSSIBILITY OF LIGHT FOG FORMATION.
SOUTHEAST WINDS TO INCREASE AFT 15Z AND ESPECIALLY AFT 18Z. THE
CHANCE OF THUNDERSTORMS IS MAINLY AFT 00Z AND HAVE VCTS MENTIONED AT
KISN/KDIK/KMOT AFT 00Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JV
LONG TERM...NH
AVIATION...JV
AREA FORECAST DISCUSSION
NWS TULSA OK
1215 AM CDT THU JUL 11 2013
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
FOR THE 6Z TAFS... VFR CONDITIONS WILL PREVAIL AT ALL TAF SITES
FOR THE ENTIRE 24 HOUR FORECAST PERIOD. ONGOING ISOLATED SHOWERS
AND THUNDERSTORMS ACROSS THE REGION ARE NOT EXPECTED TO AFFECT ANY
OF OUR SITES.
&&
.PREV DISCUSSION... /ISSUED 942 PM CDT WED JUL 10 2013/
DISCUSSION...
STORMS LINGERING FROM THE AFTERNOON OVER WEST CENTRAL AR ARE ON
THE DECLINE DUE TO THE LOSS OF SOLAR HEATING. ONCE THIS ACTIVITY
DIES OFF...THE REMAINDER OF THE NIGHT SHOULD BE MAINLY QUIET.
TOWARD 12Z...THE LATEST RUN OF THE HRRR SUGGESTS WE COULD SEE SOME
HIGH BASED ACCAS SHOWERS AND STORMS...MUCH LIKE THIS MORNING.
UPDATED TEXT PRODUCTS ARE OUT.
LACY
PREV DISCUSSION... /ISSUED 605 PM CDT WED JUL 10 2013/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
FOR THE 0Z TAFS... VFR CONDITIONS WILL PREVAIL AT ALL TAF SITES
FOR THE ENTIRE 24 HOUR FORECAST PERIOD. ONGOING WIDELY SCATTERED
THUNDERSTORMS WILL CONTINUE ACROSS THE REGION INTO THIS EVENING.
WILL INCLUDE VCTS AT ALL SITES AND WILL USE A TEMPO GROUP FOR
KMLC... WHICH APPEARS LIKELY TO BE AFFECTED BY A STORM OVER THE
NEXT HOUR OR SO.
PREV DISCUSSION... /ISSUED 311 PM CDT WED JUL 10 2013/
DISCUSSION...
ANOTHER HOT DAY WELL UNDERWAY ACROSS EASTERN OKLAHOMA AND
NORTHWEST ARKANSAS EVEN AS A COLD FRONT HAS MOVED INTO THE
AREA. THE COLD FRONT CURRENTLY EXTENDS FROM NEAR KSTL TO
NEAR KRVS WITH ANOTHER WEAK TROF OF LOW PRESSURE ACROSS
NORTHWEST ARKANSAS. SHOWERS AND A FEW THUNDERSTORMS HAVE DEVELOPED
THIS AFTERNOON IN THE VICINITY OF THE FRONTAL BOUNDARY. THE CHANCES
OF SHOWERS AND THUNDERSTORMS WILL CONTINUE NEAR THE BOUNDARY INTO
THIS EVENING. THERE IS ALSO SOME POTENTIAL FOR THE ACTIVITY TO
CONTINUE INTO THE OVERNIGHT HOURS. THERE IS THE POTENTIAL FOR
SOME OF THE STORMS TO BECOME SEVERE LATE THIS AFTERNOON AND EVENING
WITH WIND GUSTS APPROACHING 80 MPH WITH THE STRONGEST STORMS.
WILL TRIM SOME COUNTIES OFF OF THE HEAT ADVISORY AND LET THE
EXCESSIVE HEAT WARNING FOR TULSA COUNTY EXPIRE AT 01Z. WILL KEEP
THE COUNTIES SOUTH OF THE BOUNDARY IN A HEAT ADVISORY THAT WILL
CONTINUE THROUGH THURSDAY AFTERNOON. MAY SEE ISOLATED SHOWERS
AND THUNDERSTORMS ACROSS THE AREA ON THURSDAY AS THE BOUNDARY
LINGERS.
WILL KEEP THE FORECAST FROM FRIDAY INTO THE MIDDLE OF NEXT
WEEK DRY WITH TEMPERATURES AT OR SLIGHTLY ABOVE NORMAL FOR
THIS TIME OF YEAR. THE MODELS CONTINUE TO SHOW THE UPPER LEVEL
LOW CURRENTLY AFFECTING SOUTH FLORIDA MOVING WEST ACROSS SOUTH
TEXAS OVER THE WEEKEND SHOVING THE UPPER LEVEL RIDGE CURRENTLY
OVER OUR AREA TO THE NORTH. THE UPPER LEVEL LOW LOOKS TO BE TOO
FAR SOUTH TO BRING ANY SHOWER OR THUNDERSTORMS TO THE AREA.
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...HEAT ADVISORY UNTIL 7 PM THURSDAY FOR OKZ049-OKZ053-OKZ064-
OKZ065-OKZ066-OKZ070-OKZ071-OKZ073-OKZ074-OKZ075-OKZ076.
AR...NONE.
&&
$$
SHORT TERM...99
LONG TERM....99
AVIATION...06
AREA FORECAST DISCUSSION
NWS NORMAN OK
1146 PM CDT WED JUL 10 2013
.AVIATION...06Z TAF ISSUANCE...
RAIN AND THUNDER HAS CEASED FOR THE TIME BEING THIS EVENING
ACROSS OK AND WRN N TX. TO THE NW...SHOWERS AND THUNDERSTORMS
CONTINUE ACROSS FAR SERN CO AND SWRN KS. THIS ACTIVITY HAS BEEN
SLOWLY DIMINISHING THIS EVENING...BUT MAY SKIRT NWRN AND NRN
OK...IMPACTING KGAG AND KWWR. HOWEVER...FOR THE MOMENT...HAVE
DECIDED TO LEAVE ANY MENTION OF SHRA OR TSRA OUT OF THE TAFS.
OVERALL...EXPECT VFR CONDITIONS TO PERSIST...WITH MID TO HIGH
DECK OF SCT TO BKN STRATUS/STRATOCU SPREADING ACROSS THE REGION.
S/SE WINDS WILL CONTINUE TO CALM OVERNIGHT AS THE FRONT SETTLES
ACROSS THE REGION. WINDS WILL SHIFT OUT OF THE E/SE THROUGH
DAYBREAK...INCREASING SLIGHTLY THROUGH THE AFTERNOON.
JTK
&&
.PREV DISCUSSION... /ISSUED 849 PM CDT WED JUL 10 2013/
UPDATE...
UPDATED POPS THROUGH 06Z
DISCUSSION...
STORMS HAVE SLOWLY WEAKENED OVER THE PAST TWO HOURS...WITH
ISOLATED SHOWERS/THUNDER REMAINING ACROSS FAR NWRN OK. TRIMMED
BACK POPS ACROSS CENTRAL OK TO ACCOUNT FOR THIS. TO THE NW...A
DECENT MCS HAS STARTED TO DEVELOP ACROSS SERN CO AND FAR SWRN KS
THIS EVENING. THIS ACTIVITY IS EXPECTED TO SLOWLY MOVE S/SE
THROUGH THE EVENING AND OVERNIGHT.
FAR NWRN AND NRN OK WILL HAVE THE GREATEST CHANCES FOR
PRECIPITATION AS WILL THE PANHANDLES...AS CONDITIONS ARE LESS
FAVORABLE ACROSS CENTRAL AND SRN OK INTO WRN N TX FOR MCS
MAINTENANCE. MUCAPE IN THE 1000-500MB LAYER IS PALTRY...ACROSS
CENTRAL AND WRN OK...600 TO 1000 J/KG OVERNIGHT. THIS SCENARIO IS
SUPPORTED BY HRRR WITH OVERALL CONVECTION WEAKENING OVERNIGHT
ACROSS MUCH OF OKLAHOMA. HOWEVER...THERE REMAINS A CHANCE FOR
SCATTERED SHOWERS AND THUNDERSTORMS ACROSS PORTIONS OF THE AREA
THROUGH SUNRISE AS THE WEAK BOUNDARY/FRONT REMAINS POSITIONED E/W
ACROSS THE STATE.
JTK
PREV DISCUSSION... /ISSUED 343 PM CDT WED JUL 10 2013/
DISCUSSION...
THE MAIN STORY FOR THE REMAINDER OF THE WEEK WILL BE DANGEROUS
HEAT...WHICH WILL LAST THROUGH AT LEAST FRIDAY.
FOR THE REMAINDER OF TODAY...ISOLATED TO WIDELY SCATTERED STORMS
HAVE DEVELOPED ALONG A WEAK SFC FRONT/OUTFLOW BOUNDARY OVER NORTH
CENTRAL OKLAHOMA. ADDITIONAL ACTIVITY IS EXPECTED TO FORM ACROSS
WESTERN KS INTO WEST TX THROUGH THIS EVENING...POTENTIALLY MOVING
INTO FAR NORTHWEST OKLAHOMA THROUGH 03Z. WHILE LITTLE TO NO WIND
SHEAR IS PRESENT...PULSE VARIETY THUNDERSTORMS ARE EXPECTED. WITH
LARGE TEMPERATURE DEWPOINT SPREADS...EXPECT THE STRONGEST STORMS
MAY PRODUCE DAMAGING DOWNBURST WINDS OF 60 TO 70 MPH. THOUGH GUSTY
WINDS WILL BE LIKELY NEAR ANY STORM THAT DEVELOPS. OUTSIDE OF RAIN
COOLED AREAS...TEMPERATURES WILL HOVER AROUND 100 DEGREES THROUGH
THE EVENING...WITH GRADUAL COOLING BY MIDNIGHT. MOST SHOWER/STORM
ACTIVITY WILL HAVE ENDED BY THIS TIME.
THOUGH TEMPERATURES MAY COME IN A BIT COOLER BOTH TOMORROW AND
FRIDAY THAN TODAY...COMBINATION OF INCREASING LOW LEVEL MOISTURE
AND AFTERNOON HIGHS NEAR 100 DEGREES WILL LEAD TO DANGEROUS HEAT.
HEAT INDICES BOTH TOMORROW AND FRIDAY WILL TOP OUT BETWEEN 103 AND
110 DEGREES...WITH OVERNIGHT LOWS ONLY FALLING TO AROUND 80
DEGREES. WITH THIS IN MIND...HAVE OPTED TO EXTEND THE HEAT
ADVISORY BOTH IN AREA AND TIME TO COVER MUCH OF CENTRAL AND
SOUTHERN OKLAHOMA. PLEASE FOLLOW HEAT SAFETY MEASURES THROUGH THE
REMAINDER OF THE WEEK...AS THESE CONDITIONS CAN PROVE FATAL IF NOT
ADDRESSED PROPERLY.
BY THIS WEEKEND...A BROAD UPPER TROUGH WILL MOVE FROM EAST TO
WEST ALONG THE NRN GULF COAST. THIS SHOULD BRING HEIGHTS DOWN A
BIT...LEADING TO SLIGHTLY LESS HOT CONDITIONS FROM THE WEEKEND
INTO NEXT WEEK. THOUGH AFTERNOON HIGHS WILL GENERALLY REMAIN IN
THE 93 TO 100 DEGREE RANGE. WITH WEAK UPPER FORCING ALOFT...AND
IMPROVING DEEP MOISTURE...EXPECT THIS FEATURE MAY ALSO LEAD TO
ISOLATED SHOWER AND THUNDERSTORM ACTIVITY OVER SOUTHERN PORTIONS
OF OKLAHOMA AND NORTH TEXAS FOR THE EARLY TO MIDDLE PART OF NEXT
WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 101 77 99 75 / 20 30 20 20
HOBART OK 102 79 103 76 / 10 20 20 10
WICHITA FALLS TX 104 79 104 77 / 10 10 20 20
GAGE OK 99 75 98 74 / 30 60 10 10
PONCA CITY OK 100 77 95 72 / 30 30 20 10
DURANT OK 102 77 100 76 / 10 20 20 20
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...HEAT ADVISORY UNTIL 7 AM CDT SATURDAY FOR OKZ007-008-012-013-
018>020-024>032-039>043-045>048-050>052.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
208 AM EDT THU JUL 11 2013
.SYNOPSIS...
A DEEPENING UPPER TROUGH ACROSS THE GREAT LAKES WILL PUSH A COLD
FRONT INTO THE REGION THURSDAY. DISTURBANCES IN ADVANCE OF THIS
TROUGH WILL RESULT IN SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS TODAY THROUGH THURSDAY ACROSS THE REGION. BEHIND THE
COLD FRONT...COOLER...DRIER CONDITIONS ARE EXPECTED FOR FRIDAY
INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 200 AM EDT THURSDAY...
HAVE LET FFA EXPIRE AT 200 AM EDT. A NEW FFA WILL LIKELY BE
FORTHCOMING WITH THE MORNING PACKAGE...PROBABLY FOR AREAS A LITTLE
FURTHER EAST THIS TIME. WILL HIGHLIGHT DETAILS WITH LATER
DISCUSSIONS. NO OTHER CHANGES AT THIS TIME.
AS OF 800 PM EDT WEDNESDAY...
STORMS THIS EVENING HAVE BEEN VERY RAIN EFFICIENT WITH RATES OF 4
INCHES AN HOUR. THE ROANOKE REGIONAL AIRPORT RECEIVED 3.39 INCHES
OF RAIN IN ABOUT AN HOURS TIME FRAME...3.88 SO FAR FOR THE DAY...
AND NOT A GOOD MIX WHEN YOU FOCUS IT ON-TOP OF CONCRETE...WHICH
TENDS TO MAXIMIZE THE RUNOFF. WATER RESCUES SEEMED TO BECOME
COMMON PLACE THERE FOR AN HOUR OR TWO. THE ROANOKE RIVER JUMPED 5
TO 8 FEET JUST FROM THE LOCAL RUNOFF. LOOKING FOR AN EXAMPLE OF A
FLASH FLOOD... THERE YA GO.
SCATTERED SHOWERS AND STORMS WILL CONTINUE TO CONVERGE ON THE
PIEDMONT THROUGH THE EVENING HOURS WHERE THE ATMOSPHERE HAS NOT
BEEN WORKED OVER YET...CAPES STILL 1500-2000 J/KG THERE. THE LINE
OF STORMS OVER WV SHOULD WEAKEN AS THEY CROSS THE MOUNTAINS PER
STABLE AIR THAT HAS BEEN CREATED BY THE STORMS THAT OCCURRED
OVER THE CENTRAL AND WESTERN PART OF OUR CWA ALREADY. MAY SEE A
WIND GUST OF 20-30 KTS AS THE GUST FRONT ENTERS OUR WRN
COUNTIES...BUT THINK THE BIGGEST THING WE WILL HAVE TO WORRY ABOUT
IS POTENTIAL FOR ANOTHER BURST OF RAINFALL.
SURFACE COLD FRONT IS EXPECTED TO CROSS THE FORECAST AREA
THURSDAY. NOT CONFIDENT ON HOW MUCH STORM ACTIVITY WILL DEVELOP
ALONG THE FRONT PER CONVECTIVE DEBRIS THAT WILL BE LEFT IN PLACE
FROM THIS EVENINGS STORMS. PWATS WILL REMAIN HIGH...BUT THE CAPE
WILL BE DEPENDENT ON HOW QUICK THE CLOUDS BREAK THURSDAY MORNING.
WITH PWATS RANGING FROM 1.70 TO 2.0 INCHES AND A SLOW STORM
MOTION...WILL LEAVE FLASH FLOOD WATCH AS IS. FFG VALUES REMAIN
VERY LOW FROM RECENT HEAVY RAINFALL...AND THIS ADDITIONAL RAINFALL
WILL RUNOFF MORE EASILY.
USED A BLEND OF THE HRRR AND THE RNK-WRFARW FOR POPS TONIGHT INTO
THURSDAY. AS THE COLD FRONT MOVES EAST ON THURSDAY TAPER OFF POPS
FROM THE NORTHWEST TO SOUTHEAST. A STRONGER THUNDERSTORM IS POSSIBLE
IN THE SOUTH AND SOUTHEAST ON THURSDAY WITH THE POTENTIAL OF HEAVY
RAIN.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
AS OF 345 PM EDT WEDNESDAY...
THURSDAY EVENING...SURFACE FRONT WILL BE WORKING ITS WAY ACROSS
THE PIEDMONT WITH MODELS TAKING THE FRONT TO THE SANDHILLS OF NC
BEFORE STALLING FRIDAY. NOT SURE HOW MUCH CLEARING WILL TAKE PLACE
BEHIND THE FRONT AS THE UPPER LEVEL FLOW BECOMES BLOCKY WITH THE
UPPER TROUGH ALSO STALLING ALOFT. AT THE VERY LEAST THINK DRYING
WILL TAKE PLACE IN THE LOWER AND MID LEVELS AS THE AS WINDS TURN
NORTHERLY...THEN NORTHEASTERLY AS SURFACE HIGH PRESSURE TRIES TO
WEDGE INTO THE AREA FROM THE NORTH. ATTM...WILL REMAIN OPTIMISTIC
AND KEEP FORECAST DRY FOR FRIDAY THROUGH AT LEAST THE FIRST HALF
OF THE WEEKEND. AT SOME POINT WINDS WILL VEER WITH SOUTHEASTERLY
FLOW BRINGING MOISTURE BACK INTO THE FORECAST.
WENT WITH THE COOLER MAV MOS WITH THE THINKING THAT MORE CLOUD
COVER AND A NORTHEASTERLY SURFACE WIND COMPONENT WILL KEEP THE
NUMBERS DOWN.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 345 PM EDT WEDNESDAY...
CAN`T SEEM TO SHAKE THE WET PATTERN.
MODEL GUIDANCE GENERALLY AGREES THE UPPER TROUGH ALONG THE EAST
COAST WILL BECOME STUCK...POSSIBLY CUTTING OFF AND RETROGRADING
NEXT WEEK. THIS WILL QUICKLY TURN THE LOW LEVEL FLOW...WITH WINDS
CHANNELING DEEPER MOISTURE BACK INTO THE FORECAST AREA FAVORING
HIGHER POPS.
AS FOR TEMPS...DO NOT SEE ANY EXTREMES. 85H TEMPS HOVER AROUND
+16 DEG C FOR MOST OF THE WEEK. WITH A MIX OF SUN AND CLOUDS THIS
SHOULD YIELD HIGH TEMPS MAINLY IN THE 80S AND LOWS IN THE 60S.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 145 AM EDT THURSDAY...
ONCE AGAIN THE MAIN CONCERN THIS TAF VALID PERIOD WILL BE
CONVECTION. GIVEN EXTENSIVE CONVECTION ACROSS THE AREA WEDNESDAY
AND LINGERING -SHRA THIS MORNING...MVFR CIGS CAN BE EXPECTED MUCH
OF THE TIME...WITH PERIODS OF VV IFR-LIFR CIGS WHERE FOG
DEVELOPS...SUCH AS POTENTIALLY AT BCB/LYH/LWB. WE ARE SEEING A
LULL IN SHRA ACTIVITY NOW...BUT EXPECT RENEWED ACTIVITY AFT 12Z
FROM W-E AS MAIN UPPER TROUGH APPROACHES THE WEST. SHOULD SEE TSRA
DEVELOP BY MID-LATE MORNING LWB-BLF...THEN SPREAD EAST TOWARD
BCB/ROA BY 16Z...THEN TOWARD LYH/DAN BY 17/18Z. EXPECT TSRA TO END
EARLIER TODAY ACROSS WESTERN AREAS...NAMELY LWB/BLF/BCB AS DRIER
AIR PUSHES IN FROM THE WEST DURING THE MID-LATE AFTERNOON.
HOWEVER...WIDESPREAD SHRA/TSRA WILL CONTINUE ACROSS EASTERN
SECTIONS THROUGH REMAINDER OF TAF VALID PERIOD. CIGS WILL
OSCILLATE FROM VFR/MVFR OUTSIDE SHRA/TSRA ACTIVITY TO MVFR/IFR IN
TSRA ACTIVITY...BUT SHOULD PREVAIL HIGH END MVFR TO LOW END VFR.
VSBYS...LOCALIZED IFR-LIFR IN MORNING FOG...BUT PREVAILING MVFR
MOST SITES OVERNIGHT. THROUGHOUT THE DAY...EXPECT VFR VSBYS
OUTSIDE SHRA/TSRA ACTIVITY...WHEN IT COULD BE MVFR-IFR FOR BRIEF
INTERVALS. WINDS SW THROUGH AFTERNOON...TRANSITIONING TO WNW BY
AFTERNOON FROM W-E. SPEEDS LESS THAN 8KTS ALL SITES...OUTSIDE
THUNDERSTORMS.
LOW TO MEDIUM CONFIDENCE IN CIGS/VSBYS THROUGH TAF VALID PERIOD.
MEDIUM TO HIGH CONFIDENCE IN WIND SPD/DIR THROUGH TAF VALID
PERIOD.
MEDIUM CONFIDENCE IN TSRA POTENTIAL AND TIMING THROUGH TAF VALID
PERIOD.
EXTENDED AVIATION DISCUSSION...
MODELS INITIALLY PUSH DEEP CONVECTION TO THE COASTAL AREAS FRIDAY
AND SATURDAY WITH SOME CLEARING OVER THE APPALACHIANS IN THE WAKE
OF THE UPPER LEVEL TROF. RETURN FLOW HOWEVER...IS EXPECTED TO
BRING THE THREAT OF SHOWERS BACK INTO THE FORECAST FOR EARLY NEXT
WEEK...POSSIBLY AS EARLY AS SUNDAY. UNTIL THE MOISTURE
RETURNS...SHOULD SEE VFR CONDITIONS FOR THE FIRST HALF OF THE
UPCOMING WEEKEND...ASIDE FROM EARLY MORNING IFR BR/FG.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...RAB
NEAR TERM...KK/PM/RAB
SHORT TERM...PM
LONG TERM...PM
AVIATION...PM/RAB
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
157 AM EDT THU JUL 11 2013
.SYNOPSIS...
A DEEPENING UPPER TROUGH ACROSS THE GREAT LAKES WILL PUSH A COLD
FRONT INTO THE REGION THURSDAY. DISTURBANCES IN ADVANCE OF THIS
TROUGH WILL RESULT IN SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS TODAY THROUGH THURSDAY ACROSS THE REGION. BEHIND THE
COLD FRONT...COOLER...DRIER CONDITIONS ARE EXPECTED FOR FRIDAY
INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 800 PM EDT WEDNESDAY...
STORMS THIS EVENING HAVE BEEN VERY RAIN EFFICIENT WITH RATES OF 4
INCHES AN HOUR. THE ROANOKE REGIONAL AIRPORT RECEIVED 3.39 INCHES
OF RAIN IN ABOUT AN HOURS TIME FRAME...3.88 SO FAR FOR THE DAY...
AND NOT A GOOD MIX WHEN YOU FOCUS IT ON-TOP OF CONCRETE...WHICH
TENDS TO MAXIMIZE THE RUNOFF. WATER RESCUES SEEMED TO BECOME
COMMON PLACE THERE FOR AN HOUR OR TWO. THE ROANOKE RIVER JUMPED 5
TO 8 FEET JUST FROM THE LOCAL RUNOFF. LOOKING FOR AN EXAMPLE OF A
FLASH FLOOD... THERE YA GO.
SCATTERED SHOWERS AND STORMS WILL CONTINUE TO CONVERGE ON THE
PIEDMONT THROUGH THE EVENING HOURS WHERE THE ATMOSPHERE HAS NOT
BEEN WORKED OVER YET...CAPES STILL 1500-2000 J/KG THERE. THE LINE
OF STORMS OVER WV SHOULD WEAKEN AS THEY CROSS THE MOUNTAINS PER
STABLE AIR THAT HAS BEEN CREATED BY THE STORMS THAT OCCURRED
OVER THE CENTRAL AND WESTERN PART OF OUR CWA ALREADY. MAY SEE A
WIND GUST OF 20-30 KTS AS THE GUST FRONT ENTERS OUR WRN
COUNTIES...BUT THINK THE BIGGEST THING WE WILL HAVE TO WORRY ABOUT
IS POTENTIAL FOR ANOTHER BURST OF RAINFALL.
SURFACE COLD FRONT IS EXPECTED TO CROSS THE FORECAST AREA
THURSDAY. NOT CONFIDENT ON HOW MUCH STORM ACTIVITY WILL DEVELOP
ALONG THE FRONT PER CONVECTIVE DEBRIS THAT WILL BE LEFT IN PLACE
FROM THIS EVENINGS STORMS. PWATS WILL REMAIN HIGH...BUT THE CAPE
WILL BE DEPENDENT ON HOW QUICK THE CLOUDS BREAK THURSDAY MORNING.
WITH PWATS RANGING FROM 1.70 TO 2.0 INCHES AND A SLOW STORM
MOTION...WILL LEAVE FLASH FLOOD WATCH AS IS. FFG VALUES REMAIN
VERY LOW FROM RECENT HEAVY RAINFALL...AND THIS ADDITIONAL RAINFALL
WILL RUNOFF MORE EASILY.
USED A BLEND OF THE HRRR AND THE RNK-WRFARW FOR POPS TONIGHT INTO
THURSDAY. AS THE COLD FRONT MOVES EAST ON THURSDAY TAPER OFF POPS
FROM THE NORTHWEST TO SOUTHEAST. A STRONGER THUNDERSTORM IS POSSIBLE
IN THE SOUTH AND SOUTHEAST ON THURSDAY WITH THE POTENTIAL OF HEAVY
RAIN.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
AS OF 345 PM EDT WEDNESDAY...
THURSDAY EVENING...SURFACE FRONT WILL BE WORKING ITS WAY ACROSS
THE PIEDMONT WITH MODELS TAKING THE FRONT TO THE SANDHILLS OF NC
BEFORE STALLING FRIDAY. NOT SURE HOW MUCH CLEARING WILL TAKE PLACE
BEHIND THE FRONT AS THE UPPER LEVEL FLOW BECOMES BLOCKY WITH THE
UPPER TROUGH ALSO STALLING ALOFT. AT THE VERY LEAST THINK DRYING
WILL TAKE PLACE IN THE LOWER AND MID LEVELS AS THE AS WINDS TURN
NORTHERLY...THEN NORTHEASTERLY AS SURFACE HIGH PRESSURE TRIES TO
WEDGE INTO THE AREA FROM THE NORTH. ATTM...WILL REMAIN OPTIMISTIC
AND KEEP FORECAST DRY FOR FRIDAY THROUGH AT LEAST THE FIRST HALF
OF THE WEEKEND. AT SOME POINT WINDS WILL VEER WITH SOUTHEASTERLY
FLOW BRINGING MOISTURE BACK INTO THE FORECAST.
WENT WITH THE COOLER MAV MOS WITH THE THINKING THAT MORE CLOUD
COVER AND A NORTHEASTERLY SURFACE WIND COMPONENT WILL KEEP THE
NUMBERS DOWN.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 345 PM EDT WEDNESDAY...
CAN`T SEEM TO SHAKE THE WET PATTERN.
MODEL GUIDANCE GENERALLY AGREES THE UPPER TROUGH ALONG THE EAST
COAST WILL BECOME STUCK...POSSIBLY CUTTING OFF AND RETROGRADING
NEXT WEEK. THIS WILL QUICKLY TURN THE LOW LEVEL FLOW...WITH WINDS
CHANNELING DEEPER MOISTURE BACK INTO THE FORECAST AREA FAVORING
HIGHER POPS.
AS FOR TEMPS...DO NOT SEE ANY EXTREMES. 85H TEMPS HOVER AROUND
+16 DEG C FOR MOST OF THE WEEK. WITH A MIX OF SUN AND CLOUDS THIS
SHOULD YIELD HIGH TEMPS MAINLY IN THE 80S AND LOWS IN THE 60S.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 145 AM EDT THURSDAY...
ONCE AGAIN THE MAIN CONCERN THIS TAF VALID PERIOD WILL BE
CONVECTION. GIVEN EXTENSIVE CONVECTION ACROSS THE AREA WEDNESDAY
AND LINGERING -SHRA THIS MORNING...MVFR CIGS CAN BE EXPECTED MUCH
OF THE TIME...WITH PERIODS OF VV IFR-LIFR CIGS WHERE FOG
DEVELOPS...SUCH AS POTENTIALLY AT BCB/LYH/LWB. WE ARE SEEING A
LULL IN SHRA ACTIVITY NOW...BUT EXPECT RENEWED ACTIVITY AFT 12Z
FROM W-E AS MAIN UPPER TROUGH APPROACHES THE WEST. SHOULD SEE TSRA
DEVELOP BY MID-LATE MORNING LWB-BLF...THEN SPREAD EAST TOWARD
BCB/ROA BY 16Z...THEN TOWARD LYH/DAN BY 17/18Z. EXPECT TSRA TO END
EARLIER TODAY ACROSS WESTERN AREAS...NAMELY LWB/BLF/BCB AS DRIER
AIR PUSHES IN FROM THE WEST DURING THE MID-LATE AFTERNOON.
HOWEVER...WIDESPREAD SHRA/TSRA WILL CONTINUE ACROSS EASTERN
SECTIONS THROUGH REMAINDER OF TAF VALID PERIOD. CIGS WILL
OSCILLATE FROM VFR/MVFR OUTSIDE SHRA/TSRA ACTIVITY TO MVFR/IFR IN
TSRA ACTIVITY...BUT SHOULD PREVAIL HIGH END MVFR TO LOW END VFR.
VSBYS...LOCALIZED IFR-LIFR IN MORNING FOG...BUT PREVAILING MVFR
MOST SITES OVERNIGHT. THROUGHOUT THE DAY...EXPECT VFR VSBYS
OUTSIDE SHRA/TSRA ACTIVITY...WHEN IT COULD BE MVFR-IFR FOR BRIEF
INTERVALS. WINDS SW THROUGH AFTERNOON...TRANSITIONING TO WNW BY
AFTERNOON FROM W-E. SPEEDS LESS THAN 8KTS ALL SITES...OUTSIDE
THUNDERSTORMS.
LOW TO MEDIUM CONFIDENCE IN CIGS/VSBYS THROUGH TAF VALID PERIOD.
MEDIUM TO HIGH CONFIDENCE IN WIND SPD/DIR THROUGH TAF VALID
PERIOD.
MEDIUM CONFIDENCE IN TSRA POTENTIAL AND TIMING THROUGH TAF VALID
PERIOD.
EXTENDED AVIATION DISCUSSION...
MODELS INITIALLY PUSH DEEP CONVECTION TO THE COASTAL AREAS FRIDAY
AND SATURDAY WITH SOME CLEARING OVER THE APPALACHIANS IN THE WAKE
OF THE UPPER LEVEL TROF. RETURN FLOW HOWEVER...IS EXPECTED TO
BRING THE THREAT OF SHOWERS BACK INTO THE FORECAST FOR EARLY NEXT
WEEK...POSSIBLY AS EARLY AS SUNDAY. UNTIL THE MOISTURE
RETURNS...SHOULD SEE VFR CONDITIONS FOR THE FIRST HALF OF THE
UPCOMING WEEKEND...ASIDE FROM EARLY MORNING IFR BR/FG.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLASH FLOOD WATCH UNTIL 2 AM EDT EARLY THIS MORNING FOR VAZ007-
009>020-022>024-032.
NC...FLASH FLOOD WATCH UNTIL 2 AM EDT EARLY THIS MORNING FOR
NCZ001>003-018-019.
WV...FLASH FLOOD WATCH UNTIL 2 AM EDT EARLY THIS MORNING FOR
WVZ042>045.
&&
$$
SYNOPSIS...RAB
NEAR TERM...KK/PM/RAB
SHORT TERM...PM
LONG TERM...PM
AVIATION...PM/RAB
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1151 PM CDT WED JUL 10 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 313 PM CDT WED JUL 10 2013
LATEST WATER VAPOR IMAGERY SHOWED NORTHWEST FLOW ALOFT OVER THE
REGION. AN EMBEDDED SHORTWAVE WAS NOTED OVER SOUTHERN
MANITOBA...HEADING SOUTHEAST. THIS WILL BE THE FEATURE TO KEEP A
CLOSE EYE ON LATE THIS AFTERNOON THROUGH THIS EVENING AS IT MOVES
ACROSS NORTHERN/CENTRAL WISCONSIN. ELSEWHERE ACROSS THE CONUS A
TROUGH STRETCHED FROM THE EASTERN ONTARIO SOUTH THROUGH THE OHIO
RIVER VALLEY. A RIDGE WAS NOTED OVER THE ROCKIES WITH ANOTHER
TROUGH LOCATED JUST OFF OF THE WEST COAST. SURFACE OBSERVATIONS
SHOWED HIGH PRESSURE OVER THE EASTERN DAKOTAS...EDGING EAST INTO
THE UPPER MISSISSIPPI RIVER VALLEY. THE HIGH WAS PROVIDING MOSTLY
TO PARTLY SUNNY SKIES THIS AFTERNOON ACROSS THE FORECAST AREA.
NORTHWEST WINDS ARE USHERING IN A MUCH MORE COMFORTABLE AIRMASS
WITH TEMPERATURE IN THE UPPER 70S TO LOWER 80S AND DEWPOINTS IN
THE UPPER 40S TO MIDDLE 50S.
THE SHORTWAVE TROUGH WILL MOVE ACROSS NORTHWEST WISCONSIN LATE THIS
AFTERNOON AND PUSH SOUTH INTO CENTRAL WISCONSIN DURING THE EVENING
HOURS. THE RAP AND NAM CONTINUE TO PRODUCE LIGHT PRECIPITATION
WITH THIS FEATURES. ALSO...THE UPPER LEVEL SUPPORT IS FAIRLY
HEALTHY WITH 500-300 MB POTENTIAL VORTICITY ADVECTION OF 12 TO 15
PVU/S. FORECAST SOUNDINGS OVER NORTH CENTRAL AND CENTRAL WISCONSIN
ARE RATHER DRY THIS AFTERNOON AND THIS EVENING AS HIGH PRESSURE
BUILDS IN AT THE SURFACE. GIVEN THE STRENGTH OF THE WAVE WOULD
EXPECTED TO AT LEAST GET A FEW SPRINKLES OR LIGHT SHOWERS ALONG
AND NORTHEAST OF THE INTERSTATE 94 CORRIDOR THIS EVENING...MAINLY
IN THE 8PM TO 2AM TIMEFRAME. SURFACE HIGH PRESSURE WILL DOMINATE
THE WEATHER PATTERN ACROSS THE FORECAST AREA ON THURSDAY PROVIDING
MOSTLY SUNNY SKIES AND HIGHS IN THE 79 TO 83 DEGREE RANGE. DEEP
MIXING DURING THE AFTERNOON HOURS WILL ALLOW DEWPOINTS TO FALL
INTO UPPER 40S TO LOWER 50S. HAVE LOWERED DEWPOINTS A FEW DEGREES
FROM PREVIOUS FORECAST. ALSO...WILL HAVE TO KEEP AN EYE ON AREAS
OF FOG IN THE MORNING IN VALLEY LOCATIONS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 313 PM CDT WED JUL 10 2013
THE SURFACE HIGH WILL BE CENTERED OVER THE WESTERN GREAT LAKES
THURSDAY NIGHT AS AN UPPER RIDGE BUILDS IN FROM THE NORTHERN
PLAINS WITH DRY AND QUIET WEATHER IS EXPECTED THURSDAY NIGHT INTO
FRIDAY. WARMER TEMPERATURES WILL START TO FILTER BACK INTO THE
REGION AS THE HIGH SLIDES OFF TO THE EAST AND LOW PRESSURE
DEVELOPS OVER THE PLAINS. THE BREEZY SOUTHERLY FLOW OVER THE
REGION ON FRIDAY WILL ALLOW DEEP MIXING AND TEMPERATURES TO CLIMB
INTO THE MID TO UPPER 80S UNDER MOSTLY SUNNY SKIES. THE RIDGE WILL
FLATTEN SATURDAY INTO SUNDAY AS NUMEROUS EMBEDDED SHORTWAVES IN
WEST/SOUTHWEST FLOW ALOFT TRACK ACROSS THE DAKOTAS THROUGH THE
NORTHERN HALF OF MINNESOTA INTO NORTHERN WISCONSIN. THE BULK OF
THE INSTABILITY REMAINS NORTH AND WEST OF THE FORECAST AREA. THERE
IS AN INTERESTING FEATURE ADVERTISED IN THE GEM AND ECMWF...A
RETROGRADING LOW MOVES WEST OUT OF THE CENTRAL APPALACHIANS SUNDAY
INTO MONDAY AND APPROACHES THE MIDDLE MISSISSIPPI RIVER VALLEY.
WILL HAVE TO KEEP A CLOSE WATCH ON THIS FEATURE LATE IN THE
WEEKEND GOING INTO EARLY NEXT WEEK IF IT DOES MATERIALIZE.
OTHERWISE...THE UPPER RIDGE ATTEMPTS TO ANCHOR OVER THE THE
CENTRAL CONUS...STRETCHING INTO THE UPPER MISSISSIPPI RIVER
VALLEY. ZONAL FLOW ALOFT...WITH EMBEDDED SHORTWAVES...OVER THE
DAKOTAS THROUGH THE WESTERN GREAT LAKES WILL BRING PERIODIC
CHANCES FOR SHOWERS AND THUNDERSTORMS. THE BULK OF THE ACTIVITY
SHOULD OCCUR NORTH OF INTERSTATE 90 LATE THIS WEEKEND GOING INTO
THE MIDDLE OF NEXT WEEK. WITH THE WARM SOUTHERLY FLOW OVER THE
AREA AND MUCH OF THE CONVECTIVE ACTIVITY PASSING JUST TO THE NORTH
OF THE AREA...DECIDED TO WARM HIGH TEMPERATURES 1 TO 2 DEGREES
OVER A CONSENSUS MODEL BLEND...PRODUCING HIGHS IN THE UPPER 80S TO
AROUND 90
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1148 PM CDT WED JUL 10 2013
VFR CONDITIONS ARE EXPECTED THROUGH AT LEAST FRIDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...BAUMGARDT
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
430 AM MST THU JUL 11 2013
.UPDATE...UPDATED AVIATION AND FIRE WX DISCUSSIONS.
&&
.SYNOPSIS...
FAVORABLE SOUTHERLY FLOW WILL CONTINUE TO IMPORT DEEPER MONSOON
MOISTURE INTO THE REGION OVER THE NEXT COUPLE DAYS. THIS WILL LEAD
TO MORE NUMEROUS SHOWERS AND THUNDERSTORMS ACROSS THE ENTIRE AREA
LASTING THROUGH FRIDAY. THE INCREASED MOISTURE WILL ALSO RESULT IN
COOLER DAYTIME TEMPERATURES FOR THE REST OF THE WORK WEEK. WARMER
TEMPERATURES AND A GENERAL DECREASE IN THUNDERSTORM ACTIVITY CAN BE
EXPECTED OVER THE WEEKEND AND INTO EARLY NEXT WEEK.
&&
.DISCUSSION...
A BROAD SYNOPTIC SCALE INVERTED TROUGH CONTINUES TO PROPAGATE
WESTWARD TOWARDS THE GULF OF CALIFORNIA...WITH SMALL VORTICITY
CENTERS (POSSIBLY CONVECTIVELY ENHANCED) ALONG THE INTERNATIONAL
BORDER HELPING FORCE LARGE SCALE ASCENT AND CONVECTION THROUGH
SOUTHERN ARIZONA. DESPITE FAVORABLE MOISTURE PROFILES PER 00Z
SOUNDING DATA (DEEP WELL MIXED 11-14 G/KG OF MOISTURE)...WEAK
CAPPING AROUND 750MB STILL EXISTED PRECLUDING ORGANIZED STORMS FROM
SURVIVING OFF HIGHER TERRAIN. HOWEVER...OBJECTIVE ANALYSIS DEPICTS A
GENERAL COOLING AND MOISTENING OF THE ATMOSPHERIC COLUMN THROUGH
THE MORNING HOURS...LARGELY ERODING INHIBITION AND SUPPORTING
ISOLD/SCT SHOWER AND STORMS THROUGH MUCH OF THE CNTRL AND ERN PARTS
OF THE FORECAST AREA.
ONCE AGAIN EARLY THIS MORNING...NEAR TERM HRRR REFLECTIVITY
FORECASTS HAVE CAPTURED THE GENERAL TREND OF THE CURRENT
ACTIVITY...WITH SREF PROBABILITIES...DETERMINISTIC ECMWF...AND NMM
HIGH RESOLUTION CORE FORECASTS MOST AGGRESSIVE IN EXPANSION OF
ECHOES/QPF THROUGH SWRN ARIZONA THROUGH 18Z. GIVEN CURRENT RADAR
TENDS...COULD NOT DISCOUNT THESE MORE BULLISH SOLUTIONS...AND HAVE
RAISED POPS INTO A HIGHER CHANCE CATEGORY. MAY NEED FURTHER
REVISIONS/EXPANSION OF POPS UPDATED LATER THIS MORNING SHOULD TRENDS
CHANGE.
OTHERWISE...NOT A TREMENDOUS AMOUNT OF CONFIDENCE IN THE REMAINDER
OF THE FORECAST THIS AFTERNOON AND EVENING...PARTICULARLY REGARDING
CONVECTIVE EVOLUTION. STRANGELY...MANY OF THE MODELS TRADITIONALLY
BULLISH ON CONVECTION AND WITH HIGH FALSE ALARM RATES SHOW AN
UNUSUAL DEARTH OF RAINFALL THIS AFTERNOON/EVENING. THIS MAY BE DUE
TO AN ASSUMPTION OF CONVECTIVE CONTAMINATION AND CLOUD COVER
LINGERING OVER MUCH OF THE CWA DURING PEAK HEATING. ONE DISTINCT
TREND AMONG VIRTUALLY ALL MODELS WAS MORE FOCUS OF CONVECTION OVER
SERN CALIFORNIA...AND HAVE SUBSTANTIALLY INCREASED POPS IN THIS
REGION. INTERROGATION OF FORECAST SOUNDINGS FROM YUMA-IMPERIAL
INDICATE LOW MLCAPE...YET UNCAPPED PROFILES IN A WEAKLY SHEARED
ENVIRONMENT. WHILE ORGANIZED SEVERE STORMS WOULD NOT BE
EXPECTED...T/TD SPREADS ON THE ORDER OF 40F COULD STILL SUPPORT
ISOLD HIGHER WIND GUSTS. IN ADDITION...WHILE NOT THE CLASSIC HEAVY
RAIN SOUNDING...PWATS IN EXCESS OF 1.75 INCHES JUXTAPOSED WITH
UNIDIRECTIONAL WIND PROFILES OF LITTLE VERTICAL SPEED SHEAR MAY
SUPPORT TRAINING ECHOES AND LOCALLY HEAVY RAINFALL.
DEEP SOUTHERLY FLOW AND AMPLE MOISTURE PROFILES WILL PERSIST INTO
FRIDAY...SUGGESTING ACTIVE MONSOON THUNDERSTORM ACTIVITY.
HOWEVER...RECENT MODEL OUTPUT IS NOT PARTICULARLY IMPRESSIVE
REGARDING CONVECTIVE COVERAGE FRIDAY AFTERNOON/EVENING. AT THIS
POINT...IT APPEARS THE LACK OF A DYNAMIC TRIGGER...NEUTRAL JET
STRUCTURE...AND THE FIRST SIGNS OF A RETROGRESSIVE RIDGE MAY BE TO
BLAME. WITH MANY OF THE INGREDIENTS STILL PRESENT THROUGH THE
ATMOSPHERE...COULD NOT TOTALLY ELIMINATE THE POTENTIAL FOR AN ACTIVE
EVENING...HOWEVER HAVE GENERALLY TEMPERED BACK POPS FOR ALL BUT THE
HIGHER TERRAIN LOCATIONS.
A SUBTLE SHIFT IN THE OVERALL CONUS FLOW PATTERN WILL TAKE PLACE
OVER THE WEEKEND...AS A PROGRESSIVE ERN PACIFIC/PAC NW TROUGH
TRANSLATES INTO SOUTHERN CANADA CAUSING A RETROGRESSION OF FEATURES
SOUTH OF THE PRIMARY NORTHERN STREAM JET. AS SUCH...AN H5 594DM
RIDGE AXIS WILL SETTLE BACK OVER ARIZONA BRINGING A SLIGHT DRYING
TREND AND MORE LARGE SCALE SUBSIDENCE. ABOVE NORMAL TEMPERATURES AND
LOWER PRECIPITATION CHANCES OUTSIDE OF SOUTHERN GILA COUNTY APPEAR
MOST LIKELY THROUGH AT LEAST MONDAY.
BOTH THE OPERATIONAL GFS AND ECMWF NOW SHOW THE AFOREMENTIONED RIDGE
AXIS PERSISTING ACROSS THE AREA MUCH LONGER THAN PREVIOUSLY
FORECAST...WITH AN INVERTED TROUGH DECAYING AND BECOMING DEFLECTED
WELL SOUTH INTO MEXICO THROUGH THE MIDDLE OF NEXT WEEK (AS OPPOSED
TO PREVIOUS FORECASTS BRINGING A CIRCULATION CENTER DIRECTLY OVER
THE FORECAST AREA). WHILE FORECAST CONFIDENCE IN NOT OVERWHELMINGLY
HIGH...THE MODEL TREND DOES SUPPORT A FORECAST TOWARDS WARMER
TEMPERATURES AND LOWER PRECIPITATION CHANCES EVEN INTO THE MIDDLE OF
NEXT WEEK. HAVE NOT YET FULLY BOUGHT INTO THE MAGNITUDE OF WARMTH
ADVERTISED BY NUMERICAL GUIDANCE...BUT HAVE CERTAINLY INCREASED
VALUES TO A NEAR NORMAL THRESHOLD.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX...KIWA AND KSDL...
ISOLATED SHOWERS ACROSS THE METRO PHOENIX AREA SHOULD COME TO AN END
BY AROUND SUNRISE. COULD SEE ADDITIONAL SHOWERS AND THUNDERSTORMS
LATE THIS AFTERNOON AND EVENING...BUT MORE LIKELY THAN NOT THEY WILL
NOT DIRECTLY AFFECT PHOENIX TAF SITES. DUE TO THE VERY MOIST
ENVIRONMENT...CHANCES FOR STRONG OUTFLOW WINDS AND BLOWING DUST ARE
ONLY VERY SLIGHT TODAY. OVERALL...WINDS WILL FOLLOW A WESTERLY
DIRECTION FOR MOST OF THE PERIOD.
SOUTHEAST CA AND SOUTHWEST AZ...INCLUDING KIPL AND KBLH...
SHOWERS AND ISOLATED THUNDERSTORMS WILL AFFECT THE REGION THROUGH
MUCH OF THE MORNING HOURS...ESPECIALLY AT KBLH. THERE SHOULD BE A
BREAK IN THE SHOWER ACTIVITY BY LATE MORNING...BUT ADDITIONAL SHOWER
AND THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON. OVERALL WINDS
WILL REMAIN SOUTHERLY TO SOUTHEASTERLY IN NATURE WITH PERIODIC
AFTERNOON GUSTS TO NEAR 20KTS POSSIBLE.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY...
CHANCES FOR MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS
WILL REMAIN INTO THE EARLY WEEKEND...BUT A DRYING TREND WILL KEEP
STORMS MAINLY CONFINED TO THE HIGHER TERRAIN NORTH AND EAST OF
PHOENIX SUNDAY AND MONDAY. THE DRYING TREND WILL BRING MINIMUM
HUMIDITIES INTO THE TEENS ACROSS THE LOWER DESERTS FOR SUNDAY AND
MONDAY. BY TUESDAY OR WEDNESDAY...AFTERNOON MINIMUM VALUES WILL
IMPROVE...ONLY DROPPING INTO THE 20-30 PERCENT RANGE. OVERNIGHT
RECOVERY SHOULD BE GOOD TO EXCELLENT WITH READINGS CLIMBING ABOVE 40
PERCENT MOST NIGHTS. DAYTIME GUSTY WINDS ARE POSSIBLE EACH
DAY...ALONG WITH POSSIBLE THUNDERSTORM OUTFLOW BOUNDARY WINDS ON
SATURDAY AND AGAIN TUESDAY AND WEDNESDAY.
&&
$$
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...MO
AVIATION...KUHLMAN
FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS EUREKA CA
428 AM PDT THU JUL 11 2013
.SYNOPSIS...THE TRANQUIL WEATHER PATTERN WITH NEAR SEASONAL
TEMPERATURES WILL CONTINUE INTO NEXT WEEK. EXPECT MOSTLY CLEAR
SKIES ACROSS THE INTERIOR WHILE THE COAST SHOULD SEE OVERNIGHT
CLOUDS AND FOG WITH CLEARING EACH AFTERNOON.
&&
.DISCUSSION...CLOUDS AND FOG ALONG THE COAST SHOULD DISSIPATE THIS
MORNING AND AFTERNOON. OTHERWISE, THE CURRENT WEATHER PATTERN
SHOULD PERSIST INTO NEXT WEEK WITH ONLY MINIMAL CHANGES. THE COAST
CAN EXPECT MINOR FLUCTUATIONS TO THE CLOUDS AND FOG EACH DAY AND
NIGHT WHILE THE INTERIOR CAN EXPECT MINOR FLUCTUATIONS IN
AFTERNOON HIGH TEMPERATURES. A WEAK TROUGH CURRENTLY PASSING OVER
THE WEST COAST WILL BRING SLIGHTLY COOLER HIGH TEMPERATURES ACROSS
THE INTERIOR TODAY AND FRIDAY. THERE WERE NO THUNDERSTORMS WITH
THIS SYSTEM ACROSS OUR AREA YESTERDAY OR OVERNIGHT. AS THE TROUGH
MOVES INLAND TODAY THE ATMOSPHERE WILL FURTHER STABILIZE AND
MOISTURE SHOULD DECREASE. THEREFORE, REMOVED ALL THUNDERSTORMS
FROM THE FORECAST TODAY. THE TRINITY ALPS AND SURROUNDING HIGHER
TERRAIN CAN EXPECT SOME CUMULUS CLOUDS THIS AFTERNOON AT BEST.
OTHERWISE, WINDS WILL CONTINUE TO BE LIGHT AND TERRAIN DRIVEN
DURING THE DAY AND THEN VERY LIGHT AND OFFSHORE ACROSS THE
INTERIOR AT NIGHT. EXPECT A WARMING TREND WITH HOTTER TEMPERATURES
AND DRIER CONDITIONS THIS WEEKEND INTO NEXT WEEK.
&&
.AVIATION...NARROW STRIP OF LOW CLOUDS AND SOME MOSTLY LIGHT FOG
CONTINUES ALONG THE REDWOOD COAST. SAT PRODUCTS DO NOT SHOW MUCH
CHANGE IN CHARACTER OR COVERAGE OF CLOUDS DURING THE PAST FEW
HOURS. EXPECT CLOUDS TO ONCE AGAIN ERODE FROM THE E AS DAYTIME
HEATING COMMENCES. HRRR MODEL SHOWS LIGHT REVERSED S-SW FLOW ALONG
THE COAST N OF CAPE MENDO THRU MUCH OF THE DAY. THIS MAY SLOW THE
PROGRESSION OF CLOUDS BACK INLAND LATER TODAY. AT KUKI...SOME LOW
CLOUDINESS NOTED WELL S OF THE AIRPORT WITH LIGHT S WINDS AT KSTS.
WILL INCLUDE SCT LOW LAYER OF CLOUDINESS IN TAF UPDATE FOR THE
EARLY MORNING HOURS BUT NOT EXPECTED A CIG. /SEC
&&
.MARINE...FORECAST THINKING REMAINS BASICALLY UNCHANGED. STILL
APPEARS THAT WIND GUSTS WILL REMAIN BELOW GALE WARNING CRITERIA...
PERHAPS A BIT LOWER THAN PREVIOUSLY FORECAST. MARGINAL HAZARDOUS
SEAS WARNING WILL CONTINUE IN THE OFFSHORE WATERS THRU MIDNIGHT
TONIGHT. SEAS WILL CONTINUE TO BE DOMINATED BY SHORT PERIOD N WIND
DRIVEN WAVES PRODUCED BY INTERACTION OF OFFSHORE HIGH PRESSURE AND
INLAND THERMAL TROF. GRADIENT MAY RELAX A BIT EARLY NEXT WEEK...
BUT N FLOW WILL CONTINUE WITH PERIODIC WIND REVERSALS NEAR THE
COASTLINE. /SEC
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
NORTHWEST CALIFORNIA COASTAL WATERS...
HAZARDOUS SEAS WARNING FOR PZZ470-475.
SMALL CRAFT ADVISORY FOR PZZ450-470-475.
&&
$$
VISIT US AT HTTP://WWW.WEATHER.GOV/EUREKA
FOLLOW US ON FACEBOOK AND TWITTER AT:
HTTP://WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.EUREKA.GOV
HTTP://WWW.TWITTER.COM/NWSEUREKA
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1119 AM EDT THU JUL 11 2013
.SYNOPSIS...
A COLD FRONT SLOWLY MOVES INTO FAR WESTERN PORTIONS OF THE TRI-
STATE THIS AFTERNOON AND GRADUALLY SLIDES OFFSHORE LATE
TONIGHT...BEFORE STALLING OUT TO THE SOUTH OF LONG ISLAND FRIDAY.
THE WEAK FRONTAL BOUNDARY WILL DISSIPATE OVER THE AREA FRIDAY
NIGHT INTO SATURDAY. HIGH PRESSURE GRADUALLY BUILDS INTO THE
REGION FOR THE REMAINDER OF THE WEEKEND AND INTO NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AT 14Z A VERY POSITIVELY TILTED UPPER TROUGH STRETCHED FROM NE TO
SW ACROSS THE GREAT LAKES...WITH AN ASSOCIATED SURFACE COLD FRONT
STRETCHED FROM N VT INTO SW PA. LATEST WATER VAPOR IMAGERY/RADAR
IMAGERY AND LATEST MESOSCALE MODELS SUGGEST THAT AFTER CURRENT
SCT-NUMEROUS SHRA WITH EMBEDDED TSTMS LATE THIS MORNING...WILL
SEE AT MOST SCT CONVECTION THIS AFTERNOON...EXCEPT FOR MAYBE
ACROSS FAR S/E ZONES LATE. HAVE ADJUSTED POPS ACCORDINGLY. ALSO
GIVEN EXTENSIVE CLOUD COVER AND INITIAL SHRA THIS MORNING WORKING
THE LOWER LEVELS OVER /NOTE CAPES CURRENTLY 500-1000 J/KG WHILE
PREVIOUS DAYS ALREADY 1500-2500/...THAT AND NOTING MINIMAL
LIGHTNING UPSTREAM...HAVE REDUCED CHANCE OF THUNDER TO SCT. WILL
CONTINUE TO ASSESS AND MIGHT END UP REDUCING TO ISOLD WITH NEXT
UPDATE IF CURRENT TRENDS HOLD.
THAT SAID...LATEST RAP FORECAST 0-6KM SHEAR 25-40KT THIS AFTERNOON
WITH BRN 35-80...SO COULD SEE SOME ISOLATED LOW TOPPED SUPER CELLS
AND BOWING SEGMENTS...BUT STILL MAINLY PULSE STORMS LIKELY.
REFER TO THE HYDROLOGY SECTION FOR DETAILS ON EXPECTED
RAINFALL/IMPACTS.
FOR NOW TEMPERATURES FORECAST APPEARS ONT RACK...THOUGH IF CLOUD
COVER CONTINUES TO HOLD...MIGHT END UP LOWERING WITH NEXT UPDATE.
THERE IS A MODERATE RIP CURRENT RISK AT THE OCEAN BEACHES TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
TONIGHT THROUGH FRIDAY THE UPPER TROUGH AMPLIFIES WITH AN UPPER LOW
CLOSING OFF AND BECOMING CUTOFF WEST OF THE FORECAST AREA...OVER
PENNSYLVANIA...BY LATE FRIDAY. THE UPPER TROUGH BECOMES BLOCKED LATE
TONIGHT INTO FRIDAY AS THE NORTHERN ATLANTIC RIDGE BUILDS BACK TO
THE WEST. MEANWHILE AT THE SURFACE THE COLD FRONT MOVES INTO THE
REGION BY THIS AFTERNOON AND THEN MOVES VERY SLOWLY EAST THROUGH
TONIGHT AND STALLS SOUTH AND EAST OF THE REGION FRIDAY. GENERAL
AGREEMENT AMONG THE MODELS WITH THE GFS KEEPING THE FRONT AND UPPER
TROUGH A LITTLE FARTHER WEST THAN THE NAM AND ECMWF WITH THE
ATLANTIC TROUGH A LITTLE STRONGER.
THE CHANCE CONTINUES FOR SHOWERS AND THUNDERSTORMS TONIGHT INTO
FRIDAY. WITH INSTABILITY DECREASING TONIGHT SHOWERS WILL BE
POSSIBLE WITH ISOLATED THUNDER.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
MAIN PREDICTABILITY ISSUE DURING THIS PERIOD CONTINUE TO BE THE
EVOLUTION OF AN ELONGATED UPPER TROUGH ALONG THE EAST COAST TO START
THE PERIOD. ENSEMBLE AND OPERATIONAL GUIDANCE CONTINUE TO ADVERTISE
A TRANSITION OF THE TROUGH INTO A CUTOFF UPPER LOW OVER THE NORTHEAST
ON FRIDAY. 00Z OPERATIONAL GUIDANCE AND 00Z SREF AND GEFS HAVE
TRENDED TOWARDS THE UPPER LOW THEN RETROGRADING WESTWARD AS STRONG
ATLANTIC RIDGING TAKES OVER THIS WEEKEND INTO THE NEW WEEK.
IN TERMS OF SENSIBLE WEATHER...LINGERING SHOWER ACTIVITY SHOULD
GRADUALLY TAPER OFF FRIDAY NIGHT INTO SAT MORNING AS THE UPPER LOW
RETROGRADES WEST AND WEAK SURFACE FRONT DISSIPATES. WIDELY SCATTERED
SHOWERS POSSIBLE...MAINLY ACROSS INTERIOR SAT AFTERNOON WITH DIURNAL
HEATING. INSTABILITY AND FORCING LOOKS TO BE WEAK DURING THIS
TIME...SO THE THREAT FOR THUNDERSTORMS LOOKS TO BE ISOLATED AT BEST.
A CONDUCIVE HEAVY RAIN ENVIRONMENT WILL STILL MAINTAIN A THREAT FOR
HEAVY DOWNPOURS AND LOCALIZED URBAN POOR DRAINAGE FLOODING FRI NIGHT
INTO SAT.
THEREAFTER...WITH INDICATIONS THAT RIDGING WILL EVENTUALLY EXERT A
GREATER INFLUENCE SUNDAY THROUGH EARLY NEXT WEEK...POTENTIAL EXISTS
FOR A BUILDING HEATWAVE. IF 00Z OPERATIONAL GFS/GEM/ECMWF
VERIFY...FORECAST TEMPS COULD BE CONSERVATIVE...WITH POTENTIAL FOR
EXTENDED PERIOD OF HEAT ADVISORY CONDITIONS FOR NEXT WEEK. STAY
TUNED. OTHERWISE...MAINLY DRY CONDITIONS WITH ISOLATED DIURNAL
CONVECTION DEVELOPMENT POSSIBLE OFF OF SEABREEZE BOUNDARIES AND
HIGHER TERRAIN.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
A COLD FRONT APPROACHES AND MOVES THROUGH THE REGION
TODAY...PRODUCING VARYING CONDITIONS. GENERALLY VFR WITH PERIODS OF
MVFR WITH ANY PCPN.
SCT -SHRA LATE THIS MORNING SHOULD PUSH THROUGH BY 18Z. PSBL TSRA
THIS AFTN...THOUGH CONFIDENCE REMAINS MODERATE ON THE COVERAGE AND
TIMING. WILL CONTINUE AS TEMPO GROUP FOR NOW. LINGERING SHOWERS THIS
EVENING...BUT WILL NOT INCLUDE AT THIS TIME WITH LOW CONFIDENCE OF
TIMING/COVERAGE.
BKN CLOUD COVER WITH GENERALLY VFR CIGS. ANY PCPN COULD BRING CIGS
DOWN TO MVFR. VIS SHOULD REMAIN 5SM OR GREATER...THOUGH ANY HEAVY
PCPN MAY REDUCE VIS BRIEFLY.
WINDS MAINLY AROUND 10 KTS THROUGH THE DAY...THOUGH VARYING IN
DIRECTION WITH A WEAK TROUGH SETTING UP AHEAD OF THE FRONT. LOW TO
MOD CONFIDENCE ON WIND DIRECTION THROUGH THE AFTN...WITH GROWING
CONFIDENCE THIS EVENING AND OVERNIGHT.
...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)
KEWR FCSTER COMMENTS: PERIODIC PCPN THROUGH THE AFTN...ISO TSTM PSBL
AFTER 18Z. WINDS WILL VARY BETWEEN 290 AND 330 THROUGH 21Z.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KJFK FCSTER COMMENTS: PERIODIC PCPN THROUGH THE AFTN...ISO TSTM PSBL
AFTER 18Z. LOW-MOD CONFIDENCE WINDS...VARYING BETWEEN 240 AND 280
THROUGH THE AFTN.
KLGA FCSTER COMMENTS: PERIODIC PCPN THROUGH THE AFTN...ISO TSTM PSBL
AFTER 18Z. MOD CONFIDENCE WINDS REMAINING RIGHT OF 300 THROUGH
18Z...LOW CONFIDENCE AFTN WITH WINDS VARYING BETWEEN 270 AND 320.
KTEB FCSTER COMMENTS: PERIODIC PCPN THROUGH THE AFTN...ISO TSTM PSBL
AFTER 18Z. WINDS WILL VARY BETWEEN 290 AND 330 THROUGH 21Z.
KHPN FCSTER COMMENTS: PERIODIC PCPN THROUGH THE AFTN...ISO TSTM PSBL
AFTER 18Z. MOD CONFIDENCE WINDS REMAIN NW.
KISP FCSTER COMMENTS: PERIODIC PCPN THROUGH THE AFTN...ISO TSTM PSBL
AFTER 19. MOD CONFIDENCE WINDS REMAIN SW.
.OUTLOOK FOR 15Z FRIDAY THROUGH MONDAY...
.FRIDAY-FRIDAY NIGHT...SUB-VFR WITH PSBL SHRA AND TSTM DURING THE DAY
AND OVERNIGHT.
.SATURDAY-MONDAY...SUB-VFR POSSIBLE IN SHOWERS AND TSTMS ESP. N/W
OF NYC.
&&
.MARINE...
A SOUTHWESTERLY FLOW OF AROUND 15 KT LATE THIS MORNING WILL KEEP
SEAS ON THE OUTER OCEAN ZONES EAST OF FIRE ISLAND INLET AROUND 5
FEET...SO HAVE CONTINUED HAZARDOUS SEAS SMALL CRAFT ADVISORY
THROUGH NOON. MIGHT NEED TO AN EXTEND A FEW HOURS. WILL CONTINUE
TO MONITOR.
SOUTHERLY WIND IS EXPECTED TO DIMINISH AND SEAS SHOULD SUBSIDE
BELOW 5 FEET THIS AFTERNOON...WINDS AND SEAS ARE THEN EXPECTED TO
REMAIN BELOW SMALL CRAFT LEVELS THROUGH FRIDAY.
THERE WILL BE MAINLY SCT-LIKELY SHRA WITH ISOLD-SCT TSTMS THROUGH
FRIDAY AS WELL.
A WEAK FRONTAL SYSTEM WILL LIKELY DISSIPATE ACROSS THE REGION FRIDAY
NIGHT INTO EARLY SATURDAY. THERE IS POTENTIAL FOR MARGINAL SCA SEAS
DURING THIS TIME...PRIMARILY DUE TO LINGERING SOUTHERLY SWELLS.
OTHERWISE...SUB SCA CONDITIONS ARE EXPECTED FOR THE REMAINDER OF THE
WEEKEND INTO EARLY NEXT WEEK AS HIGH PRESSURE BUILDS INTO THE REGION.
&&
.HYDROLOGY...
SCATTERED TO NUMEROUS SHOWERS WITH ISOLD-SCT THUNDERSTORMS WILL
BE CAPABLE OF PRODUCING LOCALLY HEAVY RAINFALL THROUGH FRIDAY
ACROSS THE HYDROLOGIC SERVICE AREA. ALTHOUGH WIDESPREAD FLOODING
IS NOT EXPECTED AT THIS TIME...POOR DRAINAGE AND NUISANCE IS
POSSIBLE...AND LOCALIZED FLASH FLOODING IS ALSO POSSIBLE WITH ANY
TRAINING CONVECTION. GIVEN FORECAST STORM MOTION OF 15-20 KT AND
LOW-MID LEVEL FLOW NOT PARALLEL WITH FRONT...PROBABILITY OF
TRAINING/FLASH FLOODING IS LOW.
BASIN AVERAGE RAINFALL TODAY THROUGH FRIDAY NIGHT WILL BE ONE TO ONE
AND A QUARTER INCHES.
NO WIDESPREAD HEAVY RAINFALL IS EXPECTED FRIDAY NIGHT INTO EARLY
NEXT WEEK.
LOCAL HEAVY DOWNPOURS ARE POSSIBLE FRIDAY NIGHT INTO SATURDAY
MORNING ALONG A DISSIPATING FRONTAL BOUNDARY. THIS WILL POSE A
LOCALIZED URBAN AND POOR DRAINAGE FLOODING THREAT.
THEREAFTER...ISOLATED SLOW MOVING DIURNAL THUNDERSTORM ACTIVITY SUN
THROUGH WED WILL POSE A LOCALIZED URBAN AND POOR DRAINAGE FLOOD
THREAT.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL NOON EDT TODAY
FOR ANZ350-353.
&&
$$
SYNOPSIS...MALOIT/MET/NV
NEAR TERM...MALOIT/MET
SHORT TERM...MET
LONG TERM...NV
AVIATION...SEARS/DS
MARINE...MALOIT/MET/NV
HYDROLOGY...MALOIT/MET/NV
AREA FORECAST DISCUSSION
NWS MIAMI FL
959 AM EDT THU JUL 11 2013
.UPDATE...
NO MAJOR UPDATES ARE ANTICIPATED THIS MORNING AS THE PREVIOUS
FORECAST PACKAGE REMAINS ON TRACK. RECENTLY ANIMATED WATER VAPOR
LOOP SHOWED PLENTY OF MID/UPPER MOISTURE ASSOCIATED WITH THE
REMNANTS OF CHANTAL LIFTING NORTH OVER THE BAHAMAS EAST OF AN
UPPER LOW CENTERED ACROSS THE FLORIDA STRAITS. THE LATEST MODEL
GUIDANCE LINES UP WELL WITH THIS AND INDICATES THE BULK OF THIS
MOISTURE ASSOCIATED WITH CHANTAL REMAINING EAST OF SOUTH FLORIDA.
AS A RESULT...A MORE TYPICAL SUMMER-LIKE PATTERN IS ANTICIPATED
WITH MAINLY AFTERNOON SHOWERS AND THUNDERSTORMS EXPECTED TODAY.
THE LATEST HRRR AND WRF MODEL REFLECTIVITIES INDICATE ISOLATED TO
SCATTERED SHOWER/TSTM COVERAGE INITIATING AROUND 18Z AND SHIFTING
INLAND OF THE COASTAL AREAS AND CONTINUING THROUGH THE EARLY
EVENING HOURS BEFORE TRENDING DOWN.
&&
.PREV DISCUSSION... /ISSUED 740 AM EDT THU JUL 11 2013/
AVIATION...
IN ADVANCE OF THE REMNANTS OF TROPICAL STORM CHANTAL THERE IS
SOME DRIER AIR MOVING INTO THE REGION. BUT THERE WILL BE
SUFFICIENT MOISTURE FOR ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS THIS AFTERNOON, WITH MOST OF THE COVERAGE EXPECTED
TO THE WEST OF THE EAST COAST TERMINALS AND TO THE EAST OF
TERMINAL KAPF WITH VCSH ASSIGNED TO ALL TERMINALS. WITH THE
OCCURRENCE OF SHOWERS AND/OR THUNDERSTORMS, BRIEF PERIODS OF SUB-
VFR CONDITIONS ARE POSSIBLE.
PREV DISCUSSION... /ISSUED 415 AM EDT THU JUL 11 2013/
.REMNANTS OF CHANTAL TO PASS OFF TO OUR EAST WITH A TYPICAL
SUMMERTIME PATTERN EXPECTED THROUGH NEXT WEEK...
DISCUSSION...
HIGHLIGHTS...
* SCATTERED THUNDERSTORMS EACH DAY, EXCEPT NUMEROUS INTERIOR-
EAST COAST FRI-SAT AFTERNOON
* WIDESPREAD HEAVY RAINFALL NOT EXPECTED, BUT TYPICAL LOCALIZED
AMOUNTS OF 3"+ POSSIBLE EACH DAY IN THE HEAVIEST TSTORMS
SATELLITE IMAGERY SHOWS THAT THE BULK OF THE CONVECTION
ASSOCIATED WITH THE REMNANTS OF CHANTAL LIES NEAR THE SE BAHAMAS
AND IS MOVING N-NW. MODEL GUIDANCE INDEED SHOWS THAT THE VORT/BULK
OF THE MOISTURE ASSOCIATED WITH THIS REMNANT SYSTEM WILL PASS OUR
AREA TO THE EAST OVER THE BAHAMAS. MOS GUIDANCE POPS AND QPF ARE
NOT BULLISH...AND SREF PROBS OF HIGHER QPF ARE OVER THE BAHAMAS.
SO WE HAVE RATHER HIGH CONFIDENCE THIS MORNING THAT WIDESPREAD
HEAVY RAINS WILL NOT OCCUR. WPC INDEED LOWERED THEIR QPF TO AN
AREAL AVG OF AN INCH OR LESS FOR THE PERIOD TODAY-SAT. THAT BEING
SAID, IN TYPICAL SUMMERTIME FASHION, LOCALIZED HEAVY RAINFALL
AMOUNTS OF 3"+ WILL BE POSSIBLE EACH DAY IN THE HEAVIEST
THUNDERSTORMS THROUGH THE WEEKEND, SIMILAR TO WHAT HAS OCCURRED
OVER THE PAST COUPLE OF DAYS. LOCALIZED STREET FLOODING WILL BE
POSSIBLE WHERE THE HEAVY THUNDERSTORMS OCCUR.
SLIGHTLY DRIER AIR IS MOVING IN FROM THE SE TODAY WITH ONLY
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS EXPECTED, FOCUSED
OVER THE INTERIOR. MOISTURE WILL INCREASE FRI-SAT WITH PWATS NEAR
2 INCHES, WHICH IS HIGH BUT CERTAINLY NOT ATYPICAL FOR THIS TIME
OF THE YEAR. THE LOW TO MID LEVEL WIND FLOW WILL BECOME
SOUTHWESTERLY. THIS WILL FOCUS AFTERNOON THUNDERSTORMS ACROSS THE
INTERIOR AND EAST COAST METRO AREAS FRI-SAT AFTERNOON. WE EXPECT
THIS TO BE DIURNALLY DRIVEN WITH, AGAIN, THE REMNANTS OF CHANTAL
AND DEEPEST MOISTURE PASSING TO OUR EAST.
THE ATLANTIC RIDGE WILL BEGIN TO BUILD IN NORTH OF THE AREA
SUNDAY, WITH STEERING FLOW TURNING MORE EASTERLY. AN EASTERLY
WIND FLOW IS THEN EXPECTED TO PREVAIL NEXT WEEK. BOTH GFS/ECMWF
SHOW AN INVERTED LOW-MID LEVEL TROUGH MOVING ACROSS FLORIDA DURING
THE EARLY-MIDDLE PART OF NEXT WEEK. THIS COULD ENHANCE SHOWER AND
THUNDERSTORM ACTIVITY SOMEWHAT, BUT FOR NOW FOLLOWED GFS MOS WITH
ONLY CHANCE POPS THROUGH THE LONG TERM PERIOD.
MARINE...LIGHT WINDS AND LOW SEAS OF 3 FT OR LESS WILL PREVAIL
THROUGH THE PERIOD. A BRIEF INCREASE IN WINDS TO JUST AROUND 15 KT
IS FORECAST FOR THE OFFSHORE ATLANTIC WATERS LATE FRIDAY.
FIRE WEATHER...NO CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 89 77 88 75 / 30 20 60 30
FORT LAUDERDALE 87 79 88 78 / 30 20 60 30
MIAMI 89 77 89 77 / 30 20 60 30
NAPLES 87 74 87 74 / 40 20 40 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...85/AG
AVIATION/RADAR...10/CD
AREA FORECAST DISCUSSION
NWS BOISE ID
955 AM MDT THU JUL 11 2013
.DISCUSSION...ENERGY BEING EJECTED FROM AN UPPER LEVEL TROUGH IS
GOING TO CONTINUE TO IMPACT OUR AREA TODAY. AS OF 930 AM MDT...A
LARGE AREA OF CLOUD COVER EXTENDED EAST OF A LINE FROM NEAR KREO
TO NEAR KMYL. WITHIN THIS AREA...SHOWERS WERE CONCENTRATED ALONG A
LINE FROM SW TWIN FALLS COUNTY THROUGH KTWF TO JUST EAST OF KJER.
OTHER SHOWERS WERE MOVING NORTHEAST TOWARD THE OWYHEES...BUT WE DO
NOT EXPECT MEASURABLE PRECIPITATION IN THE TREASURE VALLEY THIS
MORNING. WE HAVE INCREASED THE CHANCE OF SHOWERS ACROSS THE NW
PORTION OF THE CWA IN RESPONSE TO INCREASED CONFIDENCE IN A
CONVECTIVE EVENT THIS AFTERNOON AND EVENING. THE HRRR AND NAM SHOW
CONVECTION DEVELOPING MID-AFTERNOON AND EXTENDING INTO THE EVENING
GENERALLY FROM NEAR KBNO NE TO MOST OF BAKER COUNTY. THIS
CONVECTION IS ASSOCIATED WITH A STRONG JET STREAK...120 KTS NEAR
200 MB...THAT WILL ENHANCE THE DEVELOPMENT AND LONGEVITY OF THE
CELLS THAT FORM. WE EXPECT TO GET SOME WIND GUSTS TO 50 MPH...AND
POSSIBLY OVER 60 MPH. UPDATE WILL BE OUT SHORTLY.
&&
.AVIATION...VFR. BROKEN TO OVERCAST MID LEVEL CEILING WITH WIDELY
SCATTERED SHOWERS EAST OF A KREO-KONO-KMYL LINE THIS MORNING WILL
MOVE SLOWLY EAST TODAY. AFTER 21Z ISOLATED SHOWERS AND
THUNDERSTORMS WILL DEVELOP NORTH AND WEST OF A KBNO-KMYL LINE.
THESE THUNDERSTORMS WILL LAST THROUGH 06Z WITH THE MAIN THREAT OF
STRONG GUSTY WINDS. LIGHT SURFACE WINDS THIS MORNING BECOMING
SOUTHWEST TO WEST 10-15 KNOTS WITH GUSTY WINDS NEAR THUNDERSTORMS.
WINDS ALOFT WILL BE SOUTHWESTERLY AROUND 15 KNOTS UP THROUGH 10K
FEET MSL.
&&
.PREV DISCUSSION...
SHORT TERM...TODAY THROUGH FRIDAY...SOUTHWEST FLOW BROUGHT A SURGE
OF MOISTURE INTO SW IDAHO OVERNIGHT. HOWEVER...RADAR RETURNS ARE
WEAK AND THERE IS A LACK OF SUFFICIENT INSTABILITY TO SUPPORT
THUNDERSTORMS AT THIS TIME. FURTHER WEST...ISOLATED THUNDERSTORMS
HAVE BEEN OCCURRING JUST TO THE WEST AND NORTH OF OUR CWA...
STRETCHING ACROSS NORTHEAST OREGON INTO THE IDAHO PANHANDLE. THESE
STORMS WERE SUPPORTED BY AN 80-90 KNOT UPPER JET. THE LATEST MODEL
SOLUTIONS CONTINUE TO STREAM MOISTURE INTO SW IDAHO OUT OF NEVADA
THROUGH THIS AFTERNOON. HOWEVER...INSTABILITY WILL BE WEAK DUE TO
LACK OF HEATING AND A CAP AT AROUND 450 MB WHICH WILL LIMIT DEEP
CONVECTION. SO...WILL MAINTAIN ISOLATED VS SCATTERED THUNDERSTORM
COVERAGE THIS AFTERNOON. MEANWHILE...THE UPPER JET WILL GRADUALLY
SHIFT EAST ACROSS THE AREA TODAY WHICH WILL SUPPORT ISOLATED
THUNDERSTORMS FROM NORTHERN HARNEY/MALHEUR COUNTIES INTO BAKER
COUNTY. UPPER FLOW WILL SHIFT TO A MORE WESTERLY COMPONENT TONIGHT
AND FRIDAY...SHIFTING THE BULK OF THE MOISTURE TO THE EAST EXCEPT
SOUTH OF TWIN FALLS WHICH WILL BE ON THE EDGE OF THE MOISTURE.
TEMPERATURES WILL BE LOWER TODAY...ESPECIALLY EAST OF MOUNTAIN HOME
WHERE SKIES WILL REMAIN MOSTLY CLOUDY THROUGH THE AFTERNOON. SKIES
WILL BE MOSTLY CLEAR ON FRIDAY...RESULTING IN WARMER TEMPERATURES
EAST OF MOUNTAIN HOME BUT WITH LITTLE CHANGE ELSEWHERE. ONLY MADE
MINOR CHANGES TO THE FORECAST.
LONG TERM...FRIDAY NIGHT THROUGH THURSDAY...WARM AND DRY WEATHER
THROUGH THE EXTENDED PERIOD AS SE OREGON AND SW IDAHO WILL BE
SITUATED BETWEEN AN OPEN WAVE TROUGH OVER BRITISH COLUMBIA AND AN
UPPER LEVEL HIGH PRESSURE SYSTEM CENTERED OVER THE FOUR-CORNERS
REGION. THIS PATTERN LOOKS TO PERSIST THROUGH THE END OF NEXT WEEK.
EXPECT TEMPERATURES TO BE NEAR NORMAL ON SATURDAY BEFORE WARMING UP
AS HEIGHTS GRADUALLY RISE OVER THE AREA...UP TO AROUND 10 DEGREES
ABOVE NORMAL FROM MONDAY ONWARDS.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.
&&
$$
WEATHER.GOV/BOISE
DISCUSSION...SP
AVIATION.....JA
PREV SHORT TERM...BW
PREV LONG TERM....CB
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1046 AM CDT THU JUL 11 2013
.DISCUSSION...
ISSUED 1046 AM CDT THU JUL 11 2013
NO MAJOR CHANGES TO THE FORECAST LATE THIS MORNING...JUST A FEW
TWEAKS TO HOURLY TEMPERATURES. THE LATEST SURFACE ANALYSIS
INDICATED HIGH PRESSURE CENTERED IN EXTREME NW IL...WITH A LIGHT
NORTHEAST FLOW ACROSS CENTRAL IL. DEW POINTS ARE STILL A BIT
HIGHER THAN SURROUNDING LOCATIONS BECAUSE OF PLENTY OF SOIL
MOISTURE. HOWEVER...WE SHOULD MIX UP THE LOWER ATMOSPHERE AND
BRING DRIER AIR DOWN THIS AFTERNOON AND ESPECIALLY OVERNIGHT AS
THE RIDGE AXIS MOVES OVER THE AREA.
THE 12Z ILX SOUNDING DID INDICATE A TRIGGER TEMP IN THE MIDDLE
70S...WHICH WE ARE AT RIGHT NOW. THUS...WE SHOULD SEE SOME
SCATTERED CUMULUS FORMING SOON.
MILLER
&&
.AVIATION...
ISSUED 607 AM CDT THU JUL 11 2013
HIGH PRESSURE OVER THE GREAT LAKES TO PROVIDE VFR CONDITIONS TO
CENTRAL ILLINOIS OVER THE NEXT 24 HOURS. SOME STRATOCUMULUS AROUND
5000 FEET HAS BEEN DRIFTING SOUTHWARD RECENTLY...AND HUMIDITY
CROSS SECTIONS FROM THE RAP MODEL SUGGEST SCATTERED TO
OCCASIONALLY BROKEN CLOUDS WILL CONTINUE INTO MID AFTERNOON...
BEFORE THEY ARE ERODED BY DRIER AIR ADVECTING SOUTHWEST FROM LAKE
MICHIGAN.. CLEAR SKIES ARE THEN EXPECTED OVERNIGHT. NORTHEAST
WINDS TODAY WILL GRADUALLY TURN EASTERLY TONIGHT AS THE HIGH SLIDES
FURTHER EAST.
GEELHART
&&
.PREV DISCUSSION...
ISSUED 254 AM CDT THU JUL 11 2013
SHORT TERM...TODAY THROUGH SATURDAY
HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES TODAY...PROVIDING
CENTRAL ILLINOIS WITH PLENTY OF SUNSHINE AND A DRY N/NE FLOW.
07Z/2AM SURFACE DEWPOINTS HAVE ALREADY DROPPED INTO THE LOWER TO
MIDDLE 60S AND THESE SHOULD MIX OUT INTO THE MIDDLE 50S AS THE DAY
PROGRESSES. IN ADDITION TO THE MUCH LOWER HUMIDITY VALUES
TODAY...AFTERNOON HIGH TEMPERATURES WILL ONLY REACH THE LOWER 80S.
ANY DIURNAL CLOUDINESS WILL QUICKLY DISSIPATE BY SUNSET...FOLLOWED
BY CLEAR SKIES OVERNIGHT. EXCELLENT RADIATIONAL COOLING OF THE DRY
AIR MASS WILL ALLOW LOW TEMPS TO DROP INTO THE MIDDLE TO UPPER 50S.
COOL/DRY WEATHER WILL PREVAIL THROUGH FRIDAY AS WELL...BEFORE
RISING UPPER HEIGHTS AND AIR MASS MODIFICATION PUSH HIGHS INTO THE
MIDDLE 80S BY SATURDAY.
LONG TERM...SUNDAY THROUGH WEDNESDAY
MODELS ARE BEGINNING TO INTRODUCE A POTENTIAL WRINKLE IN THE
PREVIOUS DRY FORECAST IN THE EXTENDED. UPPER SHORT-WAVE CURRENTLY
DROPPING THROUGH THE GREAT LAKES IS EXPECTED TO AMPLIFY AND
EVENTUALLY CUT-OFF OVER THE MID-ATLANTIC STATES BY FRIDAY. WHAT
HAPPENS NEXT IS STILL VERY MUCH IN QUESTION...AS MOST MODELS NOW
RETROGRADE THE CLOSED LOW WESTWARD ACROSS CENTRAL ILLINOIS ON
SUNDAY...THEN FURTHER WEST INTO THE PLAINS EARLY NEXT WEEK. THIS
WOULD BE A VERY UNUSUAL OCCURRENCE IF THIS DOES INDEED OCCUR...SO
FORECAST CONFIDENCE IS LOW. WILL WAIT TO SEE IF THE WAVE CUTS OFF
AS ADVERTISED BEFORE BUYING INTO THE WESTWARD PROGRESSION OVER THE
WEEKEND. AT THIS POINT...WILL MAINTAIN A DRY FORECAST THROUGH THE
ENTIRE PERIOD WITH HIGH TEMPERATURES CLIMBING BACK INTO THE UPPER
80S TO AROUND 90 FOR SUNDAY THROUGH WEDNESDAY. IF MODELS ARE
CORRECT...CHANCE POPS MAY NEED TO BE ADDED FOR SUNDAY/MONDAY
BEFORE LOW SHIFTS FURTHER WEST INTO THE PLAINS. MAIN STORY EARLY
NEXT WEEK WILL BE THE RETURN OF THE VERY WARM/HUMID AIR MASS...AS
SOUTHERLY WINDS WILL HELP BOOST DEWPOINTS BACK INTO THE LOWER 70S
BY MONDAY.
BARNES
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
608 AM CDT THU JUL 11 2013
.DISCUSSION...
ISSUED 254 AM CDT THU JUL 11 2013
SHORT TERM...TODAY THROUGH SATURDAY
HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES TODAY...PROVIDING
CENTRAL ILLINOIS WITH PLENTY OF SUNSHINE AND A DRY N/NE FLOW.
07Z/2AM SURFACE DEWPOINTS HAVE ALREADY DROPPED INTO THE LOWER TO
MIDDLE 60S AND THESE SHOULD MIX OUT INTO THE MIDDLE 50S AS THE DAY
PROGRESSES. IN ADDITION TO THE MUCH LOWER HUMIDITY VALUES
TODAY...AFTERNOON HIGH TEMPERATURES WILL ONLY REACH THE LOWER 80S.
ANY DIURNAL CLOUDINESS WILL QUICKLY DISSIPATE BY SUNSET...FOLLOWED
BY CLEAR SKIES OVERNIGHT. EXCELLENT RADIATIONAL COOLING OF THE DRY
AIR MASS WILL ALLOW LOW TEMPS TO DROP INTO THE MIDDLE TO UPPER 50S.
COOL/DRY WEATHER WILL PREVAIL THROUGH FRIDAY AS WELL...BEFORE
RISING UPPER HEIGHTS AND AIR MASS MODIFICATION PUSH HIGHS INTO THE
MIDDLE 80S BY SATURDAY.
LONG TERM...SUNDAY THROUGH WEDNESDAY
MODELS ARE BEGINNING TO INTRODUCE A POTENTIAL WRINKLE IN THE
PREVIOUS DRY FORECAST IN THE EXTENDED. UPPER SHORT-WAVE CURRENTLY
DROPPING THROUGH THE GREAT LAKES IS EXPECTED TO AMPLIFY AND
EVENTUALLY CUT-OFF OVER THE MID-ATLANTIC STATES BY FRIDAY. WHAT
HAPPENS NEXT IS STILL VERY MUCH IN QUESTION...AS MOST MODELS NOW
RETROGRADE THE CLOSED LOW WESTWARD ACROSS CENTRAL ILLINOIS ON
SUNDAY...THEN FURTHER WEST INTO THE PLAINS EARLY NEXT WEEK. THIS
WOULD BE A VERY UNUSUAL OCCURRENCE IF THIS DOES INDEED OCCUR...SO
FORECAST CONFIDENCE IS LOW. WILL WAIT TO SEE IF THE WAVE CUTS OFF
AS ADVERTISED BEFORE BUYING INTO THE WESTWARD PROGRESSION OVER THE
WEEKEND. AT THIS POINT...WILL MAINTAIN A DRY FORECAST THROUGH THE
ENTIRE PERIOD WITH HIGH TEMPERATURES CLIMBING BACK INTO THE UPPER
80S TO AROUND 90 FOR SUNDAY THROUGH WEDNESDAY. IF MODELS ARE
CORRECT...CHANCE POPS MAY NEED TO BE ADDED FOR SUNDAY/MONDAY
BEFORE LOW SHIFTS FURTHER WEST INTO THE PLAINS. MAIN STORY EARLY
NEXT WEEK WILL BE THE RETURN OF THE VERY WARM/HUMID AIR MASS...AS
SOUTHERLY WINDS WILL HELP BOOST DEWPOINTS BACK INTO THE LOWER 70S
BY MONDAY.
BARNES
&&
.AVIATION...
ISSUED 607 AM CDT THU JUL 11 2013
HIGH PRESSURE OVER THE GREAT LAKES TO PROVIDE VFR CONDITIONS TO
CENTRAL ILLINOIS OVER THE NEXT 24 HOURS. SOME STRATOCUMULUS AROUND
5000 FEET HAS BEEN DRIFTING SOUTHWARD RECENTLY...AND HUMIDITY
CROSS SECTIONS FROM THE RAP MODEL SUGGEST SCATTERED TO
OCCASIONALLY BROKEN CLOUDS WILL CONTINUE INTO MID AFTERNOON...
BEFORE THEY ARE ERODED BY DRIER AIR ADVECTING SOUTHWEST FROM LAKE
MICHIGAN.. CLEAR SKIES ARE THEN EXPECTED OVERNIGHT. NORTHEAST
WINDS TODAY WILL GRADUALLY TURN EASTERLY TONIGHT AS THE HIGH SLIDES
FURTHER EAST.
GEELHART
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1159 AM EDT THU JUL 11 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 218 AM EDT THU JUL 11 2013
HIGH PRESSURE WILL BRING MOSTLY DRY WEATHER TO CENTRAL INDIANA
THROUGH SATURDAY NIGHT. THEN...AN UPPER LOW WILL MOVE WEST ACROSS
THE OHIO VALLEY WHICH COULD RESULT IN A FEW SHOWERS OR THUNDERSTORMS
LATE IN THE WEEKEND AND INTO NEXT WEEK. TEMPERATURES WILL BE BELOW
NORMAL THURSDAY AND FRIDAY WITH HIGHS IN THE UPPER 70S TO LOWER 80S.
TEMPERATURES SHOULD RETURN TO NEAR NORMAL LATE IN THE WEEKEND AND
EARLY NEXT WEEK.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 955 AM EDT THU JUL 11 2013
OVERALL THE CURRENT FORECAST SEEMS TO BE ON TRACK. HIGH PRESSURE
ACROSS WISCONSIN AND IOWA WILL MOVE INTO THE LOWER GREAT LAKES BY
THIS EVENING. MADE SOME MINOR TWEAKS TO THE GRIDS MAINLY TO BACK
OFF ON SKY COVER A LITTLE MIDDAY OVER ALL BUT FAR EASTERN SECTIONS
PER RUC SOUNDINGS. LAV INDICATES TEMPERATURES MAY BE A TAD WARMER
SOME AREAS LATER TODAY. OTHERWISE...NO SIGNIFICANT CHANGES.
WILL UPDATE THE ZFP TO REFRESH WORDING.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 218 AM EDT THU JUL 11 2013
MAIN CHALLENGE TO THE SHORT TERM WILL BE CLOUDS AND POSSIBILITY OF
SHOWERS SATURDAY AND SATURDAY NIGHT AS MODELS ARE NOW IN AGREEMENT
THAT AN UPPER LOW WILL BREAK FROM THE AFOREMENTIONED SHARP UPPER
TROUGH AND RETROGRADE WEST TOWARDS THE OHIO VALLEY UNDERCUTTING A
NORTHEASTWARD EXPANDING RIDGE OF HIGH PRESSURE. THE 00Z GFS AND 00Z
GEM IN AGREEMENT ON BRINGING THIS UPPER LOW ACROSS CENTRAL INDIANA
ON SATURDAY NIGHT...WHILE THE 00Z NAM AND 12Z ECMWF ARE SLOWER TO
BRING THIS FEATURE WEST...ONLY MOVING IT TO FAR EASTERN KENTUCKY OR
CENTRAL OHIO RESPECTIVELY BY 12Z SUNDAY. WITH POSITIONING AND TIMING
IN DOUBT...WILL LEAVE IT DRY FOR NOW THROUGH SATURDAY NIGHT BUT WITH
SOME INCREASE IN CLOUD COVER SATURDAY NIGHT. OTHERWISE...SHOULD ONLY
SEE SCATTERED DIURNAL CU WITH CLEAR NIGHTTIME SKIES AS BROAD SURFACE
HIGH PRESSURE GENERAL SETTLES ACROSS SOUTHERN ONTARIO AND QUEBEC
LATE IN THE SHORT TERM.
850 MILLIBAR TEMPERATURES WARM SLIGHTLY TO 14 TO 15 DEGREES CELSIUS
BY FRIDAY AS THE HIGH SHIFTS EAST OF THE AREA. PREFER THE SLIGHTLY
COOLER 00Z NAM MOS...WHICH IS CLOSE TO ALLBLEND...BASED ON THE 850
MILLIBAR PROGS. MEANWHILE...MOS THURSDAY AND FRIDAY NIGHTTIME
TEMPERATURES CLOSE AND APPEAR REASONABLE. WITH LIGHT NORTHEAST TO
CALM WINDS...EXPECT THE USUAL RURAL AND LOW LYING AREAS TO BE
SEVERAL DEGREES COOLER AT DAWN. WILL GO WITH A MODIFIED
ALLBLEND...AND MANUALLY LOWER THOSE AREAS A COUPLE OF DEGREES.
TEMPERATURES IN RURAL AREAS COULD FALL AS LOW AS THE MID 50S.
WITH A BIT MORE CLOUD COVER...TEMPERATURES WILL NOT BE AS COOL
SATURDAY NIGHT WITH OVERNIGHT LOWS IN THE LOWER TO MID 60S EXPECTED.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
ISSUED AT 259 AM EDT THU JUL 11 2013
THE MAIN FOCUS OF THE LONG TERM PERIOD CONTINUES TO BE AN UPPER
LEVEL LOW THAT ORIGINATES OVER THE NORTHEAST U.S. AND RETROGRADES
BACK INTO THE OHIO VALLEY AND CENTRAL U.S. LATEST INITIALIZATION
HAS COMPLETELY SWITCHED FROM A DRY FORECAST IN THE EXTENDED AS
ORIGINALLY FORECASTED THE LAST FEW NIGHTS...TO NOW BRINGING PRECIP
INTO CENTRAL INDIANA FOR THE MAJORITY OF EXTENDED PERIOD IN
ASSOCIATION WITH THAT UPPER LOW. FOR NOW...DECIDED TO GO WITH
SLIGHT CHANCE POPS OVER MOST OF THE PERIOD SINCE MODELS DO TAKE
THAT LOW MORE DIRECTLY OVER CENTRAL INDIANA NOW AS OPPOSED TO THE
TENNESSEE VALLEY INDICATED IN EARLIER RUNS. HOWEVER...WOULD NOT
PUT HIGH CONFIDENCE IN THIS FORECAST DUE TO THE DRASTIC SWITCH IN
MODELS FROM RUN TO RUN. A WARM MOIST ENVIRONMENT WILL BE IN PLACE
DAILY TO CONTRIBUTE TO DESTABILIZATION AND DIURNAL THUNDERSTORMS.
HIGH TEMPS WILL BE IN THE UPPER 80S WITH DEWPOINTS IN THE UPPER
60S/LOW 70S.
&&
.AVIATION /DISCUSSION FOR THE 111800Z TAF ISSUANCE/...
ISSUED AT 1155 AM EDT THU JUL 11 2013
VFR CONDITIONS ARE GENERALLY EXPECTED FOR ENTIRE TAF PERIOD (WITH
ONE OR TWO MINOR EXCEPTIONS FRI MORNING) AS HIGH PRESSURE AND DRIER
AIR FILTER INTO CENTRAL INDIANA. DIURNAL CU HAS ALREADY BEGUN TO
DEVELOP OVER SOME OF THE AREA AROUND 030-050...BUT NOTHING THAT
WILL IMPACT OPERATIONS. WINDS WILL BE NORTHEASTERLY AT 6 TO 12
KTS...DECREASING TO AROUND 5 KT OR LESS AFTER 02Z. CLEAR SKIES
OVERNIGHT WITH SOME PATCHY MFVR BR POSSIBLE AT KBMG AFTER 09Z AND
MORNING HZ AT KIND REDUCING THE VIS TO 6SM.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...JH
SHORT TERM...MK
LONG TERM....TDUD
AVIATION...SMF
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FOLLOW US ON TWITTER AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1014 AM EDT THU JUL 11 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 218 AM EDT THU JUL 11 2013
HIGH PRESSURE WILL BRING MOSTLY DRY WEATHER TO CENTRAL INDIANA
THROUGH SATURDAY NIGHT. THEN...AN UPPER LOW WILL MOVE WEST ACROSS
THE OHIO VALLEY WHICH COULD RESULT IN A FEW SHOWERS OR THUNDERSTORMS
LATE IN THE WEEKEND AND INTO NEXT WEEK. TEMPERATURES WILL BE BELOW
NORMAL THURSDAY AND FRIDAY WITH HIGHS IN THE UPPER 70S TO LOWER 80S.
TEMPERATURES SHOULD RETURN TO NEAR NORMAL LATE IN THE WEEKEND AND
EARLY NEXT WEEK.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 955 AM EDT THU JUL 11 2013
OVERALL THE CURRENT FORECAST SEEMS TO BE ON TRACK. HIGH PRESSURE
ACROSS WISCONSIN AND IOWA WILL MOVE INTO THE LOWER GREAT LAKES BY
THIS EVENING. MADE SOME MINOR TWEAKS TO THE GRIDS MAINLY TO BACK
OFF ON SKY COVER A LITTLE MIDDAY OVER ALL BUT FAR EASTERN SECTIONS
PER RUC SOUNDINGS. LAV INDICATES TEMPERATURES MAY BE A TAD WARMER
SOME AREAS LATER TODAY. OTHERWISE...NO SIGNIFICANT CHANGES.
WILL UPDATE THE ZFP TO REFRESH WORDING.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 218 AM EDT THU JUL 11 2013
MAIN CHALLENGE TO THE SHORT TERM WILL BE CLOUDS AND POSSIBILITY OF
SHOWERS SATURDAY AND SATURDAY NIGHT AS MODELS ARE NOW IN AGREEMENT
THAT AN UPPER LOW WILL BREAK FROM THE AFOREMENTIONED SHARP UPPER
TROUGH AND RETROGRADE WEST TOWARDS THE OHIO VALLEY UNDERCUTTING A
NORTHEASTWARD EXPANDING RIDGE OF HIGH PRESSURE. THE 00Z GFS AND 00Z
GEM IN AGREEMENT ON BRINGING THIS UPPER LOW ACROSS CENTRAL INDIANA
ON SATURDAY NIGHT...WHILE THE 00Z NAM AND 12Z ECMWF ARE SLOWER TO
BRING THIS FEATURE WEST...ONLY MOVING IT TO FAR EASTERN KENTUCKY OR
CENTRAL OHIO RESPECTIVELY BY 12Z SUNDAY. WITH POSITIONING AND TIMING
IN DOUBT...WILL LEAVE IT DRY FOR NOW THROUGH SATURDAY NIGHT BUT WITH
SOME INCREASE IN CLOUD COVER SATURDAY NIGHT. OTHERWISE...SHOULD ONLY
SEE SCATTERED DIURNAL CU WITH CLEAR NIGHTTIME SKIES AS BROAD SURFACE
HIGH PRESSURE GENERAL SETTLES ACROSS SOUTHERN ONTARIO AND QUEBEC
LATE IN THE SHORT TERM.
850 MILLIBAR TEMPERATURES WARM SLIGHTLY TO 14 TO 15 DEGREES CELSIUS
BY FRIDAY AS THE HIGH SHIFTS EAST OF THE AREA. PREFER THE SLIGHTLY
COOLER 00Z NAM MOS...WHICH IS CLOSE TO ALLBLEND...BASED ON THE 850
MILLIBAR PROGS. MEANWHILE...MOS THURSDAY AND FRIDAY NIGHTTIME
TEMPERATURES CLOSE AND APPEAR REASONABLE. WITH LIGHT NORTHEAST TO
CALM WINDS...EXPECT THE USUAL RURAL AND LOW LYING AREAS TO BE
SEVERAL DEGREES COOLER AT DAWN. WILL GO WITH A MODIFIED
ALLBLEND...AND MANUALLY LOWER THOSE AREAS A COUPLE OF DEGREES.
TEMPERATURES IN RURAL AREAS COULD FALL AS LOW AS THE MID 50S.
WITH A BIT MORE CLOUD COVER...TEMPERATURES WILL NOT BE AS COOL
SATURDAY NIGHT WITH OVERNIGHT LOWS IN THE LOWER TO MID 60S EXPECTED.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
ISSUED AT 259 AM EDT THU JUL 11 2013
THE MAIN FOCUS OF THE LONG TERM PERIOD CONTINUES TO BE AN UPPER
LEVEL LOW THAT ORIGINATES OVER THE NORTHEAST U.S. AND RETROGRADES
BACK INTO THE OHIO VALLEY AND CENTRAL U.S. LATEST INITIALIZATION
HAS COMPLETELY SWITCHED FROM A DRY FORECAST IN THE EXTENDED AS
ORIGINALLY FORECASTED THE LAST FEW NIGHTS...TO NOW BRINGING PRECIP
INTO CENTRAL INDIANA FOR THE MAJORITY OF EXTENDED PERIOD IN
ASSOCIATION WITH THAT UPPER LOW. FOR NOW...DECIDED TO GO WITH
SLIGHT CHANCE POPS OVER MOST OF THE PERIOD SINCE MODELS DO TAKE
THAT LOW MORE DIRECTLY OVER CENTRAL INDIANA NOW AS OPPOSED TO THE
TENNESSEE VALLEY INDICATED IN EARLIER RUNS. HOWEVER...WOULD NOT
PUT HIGH CONFIDENCE IN THIS FORECAST DUE TO THE DRASTIC SWITCH IN
MODELS FROM RUN TO RUN. A WARM MOIST ENVIRONMENT WILL BE IN PLACE
DAILY TO CONTRIBUTE TO DESTABILIZATION AND DIURNAL THUNDERSTORMS.
HIGH TEMPS WILL BE IN THE UPPER 80S WITH DEWPOINTS IN THE UPPER
60S/LOW 70S.
&&
.AVIATION /DISCUSSION FOR THE 111430Z TAF UPDATE/...
ISSUED AT 1012 AM EDT THU JUL 11 2013
NO CHANGES NEEDED AT THIS TIME. PREVIOUS DISCUSSION FOLLOWS...
VFR CONDITIONS EXPECTED FOR ENTIRE TAF PERIOD AS HIGH
PRESSURE/DRIER AIR FILTER INTO CENTRAL INDIANA. DIURNAL CU COULD
DEVELOP FROM 030-050...BUT NOTHING THAT WILL IMPACT OPERATIONS.
WINDS WILL BE NORTHEASTERLY AT 6 TO 12 KTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...JH
SHORT TERM...MK
LONG TERM....TDUD
AVIATION...SMF/TDUD
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
955 AM EDT THU JUL 11 2013
.UPDATE...
NEAR TERM FOR THE REST OF TODAY HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 218 AM EDT THU JUL 11 2013
HIGH PRESSURE WILL BRING MOSTLY DRY WEATHER TO CENTRAL INDIANA
THROUGH SATURDAY NIGHT. THEN...AN UPPER LOW WILL MOVE WEST ACROSS
THE OHIO VALLEY WHICH COULD RESULT IN A FEW SHOWERS OR THUNDERSTORMS
LATE IN THE WEEKEND AND INTO NEXT WEEK. TEMPERATURES WILL BE BELOW
NORMAL THURSDAY AND FRIDAY WITH HIGHS IN THE UPPER 70S TO LOWER 80S.
TEMPERATURES SHOULD RETURN TO NEAR NORMAL LATE IN THE WEEKEND AND
EARLY NEXT WEEK.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 955 AM EDT THU JUL 11 2013
OVERALL THE CURRENT FORECAST SEEMS TO BE ON TRACK. HIGH PRESSURE
ACROSS WISCONSIN AND IOWA WILL MOVE INTO THE LOWER GREAT LAKES BY
THIS EVENING. MADE SOME MINOR TWEAKS TO THE GRIDS MAINLY TO BACK
OFF ON SKY COVER A LITTLE MIDDAY OVER ALL BUT FAR EASTERN SECTIONS
PER RUC SOUNDINGS. LAV INDICATES TEMPERATURES MAY BE A TAD WARMER
SOME AREAS LATER TODAY. OTHERWISE...NO SIGNIFICANT CHANGES.
WILL UPDATE THE ZFP TO REFRESH WORDING.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 218 AM EDT THU JUL 11 2013
MAIN CHALLENGE TO THE SHORT TERM WILL BE CLOUDS AND POSSIBILITY OF
SHOWERS SATURDAY AND SATURDAY NIGHT AS MODELS ARE NOW IN AGREEMENT
THAT AN UPPER LOW WILL BREAK FROM THE AFOREMENTIONED SHARP UPPER
TROUGH AND RETROGRADE WEST TOWARDS THE OHIO VALLEY UNDERCUTTING A
NORTHEASTWARD EXPANDING RIDGE OF HIGH PRESSURE. THE 00Z GFS AND 00Z
GEM IN AGREEMENT ON BRINGING THIS UPPER LOW ACROSS CENTRAL INDIANA
ON SATURDAY NIGHT...WHILE THE 00Z NAM AND 12Z ECMWF ARE SLOWER TO
BRING THIS FEATURE WEST...ONLY MOVING IT TO FAR EASTERN KENTUCKY OR
CENTRAL OHIO RESPECTIVELY BY 12Z SUNDAY. WITH POSITIONING AND TIMING
IN DOUBT...WILL LEAVE IT DRY FOR NOW THROUGH SATURDAY NIGHT BUT WITH
SOME INCREASE IN CLOUD COVER SATURDAY NIGHT. OTHERWISE...SHOULD ONLY
SEE SCATTERED DIURNAL CU WITH CLEAR NIGHTTIME SKIES AS BROAD SURFACE
HIGH PRESSURE GENERAL SETTLES ACROSS SOUTHERN ONTARIO AND QUEBEC
LATE IN THE SHORT TERM.
850 MILLIBAR TEMPERATURES WARM SLIGHTLY TO 14 TO 15 DEGREES CELSIUS
BY FRIDAY AS THE HIGH SHIFTS EAST OF THE AREA. PREFER THE SLIGHTLY
COOLER 00Z NAM MOS...WHICH IS CLOSE TO ALLBLEND...BASED ON THE 850
MILLIBAR PROGS. MEANWHILE...MOS THURSDAY AND FRIDAY NIGHTTIME
TEMPERATURES CLOSE AND APPEAR REASONABLE. WITH LIGHT NORTHEAST TO
CALM WINDS...EXPECT THE USUAL RURAL AND LOW LYING AREAS TO BE
SEVERAL DEGREES COOLER AT DAWN. WILL GO WITH A MODIFIED
ALLBLEND...AND MANUALLY LOWER THOSE AREAS A COUPLE OF DEGREES.
TEMPERATURES IN RURAL AREAS COULD FALL AS LOW AS THE MID 50S.
WITH A BIT MORE CLOUD COVER...TEMPERATURES WILL NOT BE AS COOL
SATURDAY NIGHT WITH OVERNIGHT LOWS IN THE LOWER TO MID 60S EXPECTED.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
ISSUED AT 259 AM EDT THU JUL 11 2013
THE MAIN FOCUS OF THE LONG TERM PERIOD CONTINUES TO BE AN UPPER
LEVEL LOW THAT ORIGINATES OVER THE NORTHEAST U.S. AND RETROGRADES
BACK INTO THE OHIO VALLEY AND CENTRAL U.S. LATEST INITIALIZATION
HAS COMPLETELY SWITCHED FROM A DRY FORECAST IN THE EXTENDED AS
ORIGINALLY FORECASTED THE LAST FEW NIGHTS...TO NOW BRINGING PRECIP
INTO CENTRAL INDIANA FOR THE MAJORITY OF EXTENDED PERIOD IN
ASSOCIATION WITH THAT UPPER LOW. FOR NOW...DECIDED TO GO WITH
SLIGHT CHANCE POPS OVER MOST OF THE PERIOD SINCE MODELS DO TAKE
THAT LOW MORE DIRECTLY OVER CENTRAL INDIANA NOW AS OPPOSED TO THE
TENNESSEE VALLEY INDICATED IN EARLIER RUNS. HOWEVER...WOULD NOT
PUT HIGH CONFIDENCE IN THIS FORECAST DUE TO THE DRASTIC SWITCH IN
MODELS FROM RUN TO RUN. A WARM MOIST ENVIRONMENT WILL BE IN PLACE
DAILY TO CONTRIBUTE TO DESTABILIZATION AND DIURNAL THUNDERSTORMS.
HIGH TEMPS WILL BE IN THE UPPER 80S WITH DEWPOINTS IN THE UPPER
60S/LOW 70S.
&&
.AVIATION /DISCUSSION FOR THE 11/1200Z TAF ISSUANCE/...
ISSUED AT 627 AM EDT THU JUL 11 2013
VFR CONDITIONS EXPECTED FOR ENTIRE TAF PERIOD AS HIGH
PRESSURE/DRIER AIR FILTER INTO CENTRAL INDIANA. DIURNAL CU COULD
DEVELOP FROM 030-050...BUT NOTHING THAT WILL IMPACT OPERATIONS.
WINDS WILL BE NORTHEASTERLY AT 6 TO 12 KTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...JH
SHORT TERM...MK
LONG TERM....TDUD
AVIATION...TDUD
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
715 AM CDT THU JUL 11 2013
...UPDATED FOR AVIATION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 358 AM CDT THU JUL 11 2013
THE SURFACE FRONT THAT WAS LOCATED ACROSS SOUTHWEST KANSAS
WEDNESDAY AFTERNOON WAS GETTING ANOTHER BOOST SOUTHWARD FROM
OVERNIGHT THUNDERSTORM OUTFLOW. UPPER LEVEL RIDGING WILL BE EDGING
BACK OVER THE CENTRAL PLAINS OVER THE NEXT 24 TO 36 HRS. HOWEVER,
THE EFFECTIVE FRONTAL BOUNDARY MAY BE SLOW TO MOVE BACK TO THE NORTH
TODAY. INSTEAD OF MORE OF A SOUTHERLY WIND PER THE NAM MODEL, WITH
TEMPERATURES REACHING 100-102F, MORE OF A SOUTHEASTERLY UPSLOPE WIND
MAY SERVE TO KEEP TEMPERATURES FROM REACHING 100F PER RAP MODEL
(WITH MID TO UPPER 90S MORE LIKELY. IN ADDITION, ANY ONGOING
CONVECTION OVER SOUTH CENTRAL AND CENTRAL KANSAS THIS MORNING COULD
HELP KEEP TEMPERATURES COOLER ALONG A MEDICINE LODGE TO HAYS
CORRIDOR THIS AFTERNOON DUE TO OUTFLOW FROM THE SOUTHEAST. KEEP
IN MIND THAT LEE TROUGHING WILL BE STRENGTENING IN THE LEE OF THE
ROCKIES THIS AFTERNOON IN REPONSE TO STRONG SOUTHWEST MID LEVEL
FLOW ACROSS THE NORTHERN ROCKIES. THIS WOULD TEND TO PROMOTE
MORE OF A SOUTH WIND AND HOTTER TEMPERATURES FOR TODAY. SO DESPITE
THE OUTFLOW, I WOULD NOT BE SURPRISED IF TEMPERATURES ROSE TO OVER
100 DEGREES IN DODGE CITY BY THIS AFTERNOON--HENCE THE FORECAST
UNCERTAINTY. BY LATE AFTERNOON, A CORRIDOR OF 2000 J/KG SURFACE
BASED CAPE WILL BE SITUATED FROM DODGE CITY TO DIGHTON AND SCOTT
CITY. ISOLATED THUNDERSTORMS CANNOT BE RULED OUT. UPPER LEVEL WINDS
WILL BE QUITE A BIT WEAKER TODAY THAN ON WEDNESDAY ALONG THE
INTERSTATE 70 CORRIDOR SO THAT ANY HAIL WOULD BE QUARTER SIZE OR
SMALLER. ANY CONVECTION THAT DEVELOPS LATE THIS AFTERNOON SHOULD
WEAKEN THIS EVENING WITH THE LOSS OF DAYTIME HEATING GIVEN THE LACK
OF UPPER LEVEL SUPPORT. TEMPERATURES TONIGHT WILL BE HELD UP BY
SOUTH WINDS, WITH LOWS IN THE LOWER TO MID 70S.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 254 AM CDT THU JUL 11 2013
A RETURN TO HOT AND DRY CONDITIONS IS FORECAST FOR FRIDAY SATURDAY
AND POSSIBLY BEYOND, AS AN UPPER HIGH PRESSURE RIDGE ROTATES INTO THE
HIGH PLAINS REGION AND BECOMES STATIONARY FOR A FEW DAYS. FORECAST
MODELS DO SHOW CONSIDERABLE SPREAD FROM AROUND 100 DEGREES INTO THE
MID 100`S BOTH DAY AS THE WARM BOUNDARY LAYER PLUME OVERSPREAD THE
AREA WITH 27-30 DEGREES C 850 MB AIR. IF THE WARMEST OF FORECAST
SOLUTIONS VERIFY ACROSS CENTRAL KANSAS, DANGEROUS HEAT INDICES COULD
BE ACHIEVED IN THE AFTERNOON. THE PATTERN BECOMES MORE FLATTENED
AFTER FRIDAY, AND JUST HOW WARM THE HIGHS GET IN THE AFTERNOON ARE
LESS CLEAR. BY MONDAY, THE ECMWF SHOWS A FRONT IN THE VICINITY OF
NORTHWEST KANSAS AND SW NEBRASKA. THAT KIND OF PATTERN WOULD
RELEGATE STORMS TO THE FRONT WITH A LACK OF STEERING FLOW. A RESULT
OF THE NEARLY STATIONARY UPPER HIGH WILL BE SURFACE WINDS BECOMING
MORE LIGHT AND VARIABLE WITH TIME AS THE SUBSIDENCE INDUCED SURFACE
HIGH MAINTAINS INCREASING HIGH PRESSURE FROM THE NORTHERN PLAINS.
LIGHT AND VARIABLE OR LIGHT EASTERLY FLOW WOULD SUPPORT NOT AS HOT
TEMPERATURES IN THE MID TO UPPER 90S AND LOWER FREQUENCIES OF 100
DEGREE AND HIGH READINGS. ISOLATED ELEVATED THUNDERSTORMS CAN`T BE
RULED OUT COMPLETELY MID TO LATE WEEK AS MODELS SHOW A SUBTLE SIGNAL
OF MID LEVEL MOISTURE SPREADING NORTHWARD ON THE BACK SIDES OF THE
UPPER HIGH PRESSURE. CONFIDENCE IS TOO LOW HOWEVER TO RAISE THE
CURRENT ALLBLEND APPROACH OF SINGLE DIGIT PRECIPITATION
PROBABILITIES DURING THIS TIMEFRAME. .
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 714 AM CDT THU JUL 11 2013
CONVECTION CONTINUES TO SHIFT FARTHER INTO NORTH CENTRAL KANSAS,
AWAY FROM THE KHYS TERMINAL. VFR CONDITIONS WILL PREVAIL ACROSS THE
AREA THROUGH THE DAY. ONLY ISOLATED THUNDERSTORMS ARE EXPECTED IN
THE LATE AFTERNOON, TOO LOW TO CONSIDER FOR ANY TERMINAL.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 99 73 104 74 / 20 10 0 0
GCK 99 73 104 73 / 20 20 0 0
EHA 98 72 103 71 / 10 10 0 0
LBL 99 72 104 73 / 20 10 0 0
HYS 97 73 104 75 / 20 20 0 0
P28 97 74 102 75 / 20 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...FINCH
LONG TERM...RUSSELL
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
555 AM MDT THU JUL 11 2013
.UPDATE...
ISSUED AT 549 AM MDT THU JUL 11 2013
LESS CONVECTION AROUND AT THIS TIME THAN PREVIOUSLY ANTICIPATED.
THERE STILL OUTFLOW BOUNDARIES AROUND SO LEFT IN A 20 TO 30
PERCENT CHANCE THROUGH 15Z. ALSO ADJUSTED SKY COVER AND WINDS
BASED ON LATEST TRENDS.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 415 AM MDT THU JUL 11 2013
FORECAST CONCERNS WILL BE CHANCE OF THUNDERSTORMS FOLLOWED BY HOW
HOT DOES IT GET ALONG WITH POSSIBLE HEAT HIGHLIGHTS. SATELLITE
SHOWING A RATHER AMPLIFIED PATTERN FROM THE PACIFIC IN CENTRAL NORTH
AMERICA. MOISTURE AND WEAK SHORTWAVE TROUGHS ROTATING AROUND UPPER
HIGH CENTERED TO OUR SOUTH/SOUTHWEST. FRONTAL BOUNDARY AT THIS TIME
REMAINS DRAPED TO OUR SOUTH AND WEST.
AT MID LEVELS...THE UKMET FOLLOWED BY THE CANADIAN AND GFS WERE
DOING BEST ON WHERE THE CENTER OF THE MID/UPPER HIGH WAS AND THE
RESULTING HEIGHT FIELD OVER THE AREA. OUTFLOW BOUNDARIES ARE
MESSING UP THE WIND FIELD RIGHT AND THE HRRR HAS THE RIGHT IDEA ON
IT. UKMET AND CANADIAN WERE DOING A LITTLE BETTER THAN THE GFS AND
ECMWF ON THE LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...HOW MUCH THUNDERSTORM ACTIVITY WILL BE AROUND THIS
MORNING AND LINGERING MESOSCALE AFFECTS FROM THESE THUNDERSTORMS WILL
BE AROUND FOR THE ENTIRE DAY ARE THE BIG QUESTIONS WHICH MAY BE VERY
HARD TO ANSWER. PERSISTENT CLUSTER OF THUNDERSTORMS REMAINS OVER THE
EASTERN PORTION OF THE AREA. THIS AREA WAS THE RESULT A WEAK
SHORTWAVE IN THE AREA BUT MOST OF ALL THE COLLISION OF OUTFLOW
BOUNDARIES. OUTFLOW BOUNDARIES ABOUND ACROSS THE AREA PER RADAR AND
SURFACE OBSERVATIONS AND ESPECIALLY IN THE EASTERN AND CENTRAL
PORTION. ELEVATED CAPE AND LACK OF STRONG ELEVATED CINH WILL BE
AROUND AT THE BEGINNING OF THE DAY. ADDITIONAL DEVELOPMENT IS
OCCURRING AND IS EXPECTED TO CONTINUE TO OCCUR. SO ISSUED THE ZONES
WITH A PRE-FIRST PERIOD AND KEPT POPS AROUND IN THE MORNING...
ESPECIALLY IN THE EAST. WILL CONTINUE TO MONITOR AND WILL ISSUE AN
UPDATE NEAR 12Z TO ACCOUNT FOR THE LATEST TRENDS WHICH THE MODELS ARE
PLAYING CATCH UP WITH.
NOT ACCOUNTING FOR MESOSCALE INFLUENCES OVERNIGHT GUIDANCE HAD THE
HIGHEST INSTABILITY AND LOWEST 700 MB TEMPERATURES IN THE EASTERN
PORTION OF THE AREA. AT 500 MB WEAK SHORTWAVE IS MOVING ACROSS THE
EASTERN HALF IN THE AFTERNOON. AT 700 MB A SHORTWAVE TROUGH BEGINS
TO AFFECT THE WESTERN PORTION BUT THE 700 MB TEMPERATURES ARE MUCH
WARMER. SATELLITE WOULD ALSO INDICATE ANOTHER INFLUX OF MID LEVEL
SUBTROPICAL MOISTURE FROM THE WEST. AND THE BIGGEST VARIABLE IS
WHERE WILL THERE BE LEFTOVER OUTFLOW BOUNDARIES. WOULD SAY THERE IS
A GOOD PROBABILITY OF ONE OR MORE IN THE CENTRAL AND EASTERN PORTION
OF THE AREA. SO TO ACCOUNT FOR THIS...PUT SLIGHT CHANCE IN THE WEST
AND LOW CHANCE IN THE EAST.
DEPENDING ON HOW PERSISTENT THE CONVECTION STAYS...HOW MUCH CLOUD
COVER HANGS AROUND...AND HOW SIGNIFICANT THE OUTFLOW IS...HIGH
TEMPERATURES MAY BE SEVERELY AFFECTED. BELIEVE THIS CONVECTION WILL
ALSO KEEP THE SYNOPTIC FRONT SUPPRESSED FURTHER TO THE SOUTH AND
WEST. KEPT THE COOLEST EAST AND THE WARMEST WEST BUT THAT IS HIGHLY
PROBLEMATIC AT THIS POINT.
FRIDAY/FRIDAY NIGHT...IN REGARDS TO THE PRECIPITATION...NEWEST MODEL
GUIDANCE SUPPORTS THE PREVIOUS FORECAST VERY WELL. RIDGE STARTS
BUILDING INTO THE AREA BUT THE MODELS DISAGREE ON HOW MUCH. MID
LEVEL TEMPERATURES WARM AND IT DOES LOOK LIKE MOST OF THE FORECAST
AREA EAST OF THE COLORADO BORDER DOES STAY CAPPED. A SURFACE TROUGH
SUPPLYING LOW LEVEL CONVERGENCE ALONG WITH A WEAK SHORTWAVE AFFECT
THE FAR WESTERN PORTION OF THE AREA WHICH IS WHERE THE 700 MB
TEMPERATURES ARE THE WARMEST. SO MADE LITTLE IF ANY CHANGE TO THE
PRECIPITATION FORECAST. NEW GUIDANCE SUPPORTS WARMING UP NOT ONLY
MAXES BUT THE MINS AS WELL. MOST OF THE AREA SHOULD BE ABOVE 100
DEGREES WITH THE EASTERN HALF THE HOTTEST FOR THE MAXES.
THIS COULD BE THE BEGINNING OF AN EXTENDED HEAT HIGHLIGHT FOR THE
EASTERN PORTION OF THE AREA. HEAT INDICES IN THE AFTERNOON REACH
105 IN THE EASTERN SIX COUNTIES DURING THE DAY. THEN OVERNIGHT MINS
DO NOT DROP OFF VERY MUCH AND I ACTUALLY MAY BE TOO COOL.
SATURDAY/SATURDAY NIGHT...SIMILAR SCENARIO FOR PRECIPITATION THESE
TWO PERIODS AS THE PREVIOUS TWO. THE MID/UPPER RIDGE LOOKS TO BUILD
IN MORE WITH HIGHER 700 MB TEMPERATURES AND ALSO LESS SURFACE
CONVERGENCE NEAR THE WESTERN END OF THE FORECAST AREA. WEAK LIFT IN
ADDITION TO THE EXTREME HEATING...COULD HELP SET OFF A FEW
THUNDERSTORMS. ALMOST CANNOT HELP BUT INITIATE THUNDERSTORMS IN
THIS KIND OF HEATING. CURRENT FORECAST HAD THIS SCENARIO WELL IN
HAND AND DID NOT CHANGE ANYTHING. MODELS LOOK TO INCREASE THE HEAT.
IT IS POSSIBLE I STILL DO NOT HAVE THE MAXES HOT ENOUGH...ESPECIALLY
IN THE EASTERN HALF. MINS LOOKS JUST AS WARM OR WARMER THAN THE
PREVIOUS NIGHT.
HEAT INDICES OF 105 PUSH ONE ROW OF COUNTIES FURTHER WEST THAN THE
PREVIOUS DAY. AM NOT ISSUING A HEAT HIGHLIGHT YET...BUT PLAN ON
MENTIONING THE FRIDAY INTO SATURDAY NIGHT PERIOD IN THE HWO.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 415 AM MDT THU JUL 11 2013
A LARGER THAN NORMAL DEGREE OF UNCERTAINTY IN THE EXTENDED
ON THE SYNOPTIC SCALE...THOUGH MOST SOLUTIONS END UP WITH SIMILAR
CONDITIONS FOR THE HIGH PLAINS. MAIN STORY EARLY NEXT WEEK WILL BE
HIGHS NEAR TO SLIGHTLY ABOVE NORMAL WITH GENERALLY DRY CONDITIONS.
ON SUNDAY A WEAK UPPER LEVEL DISTURBANCE MOVES ACROSS THE CENTRAL
ROCKIES AND INTO THE HIGH PLAINS...WHICH COULD HELP TO DEVELOP A FEW
SHOWERS/STORMS ON SUNDAY AFTERNOON INTO THE EVENING. TEMPS WILL BE
WARMEST ON SUNDAY WITH 850 TEMPS IN THE MID TO UPPER 20S...THOUGH
THE EC IS AN OUTLIER WITH SLIGHTLY COOLER TEMPS. THE REST OF THEE
WEEK MOST DETERMINISTIC GUIDANCE SHOWS AN UPPER LOW OVER MID-WEST
AND MOVING WEST AS IT WEAKENS...THOUGH AT THIS POINT BELIEVE THE
UPPER LOW WILL REMAIN FARTHER EAST AND AN UPPER RIDGE WILL BE OVER
HIGH PLAINS KEEPING THINGS DRY. 850 TEMPS FOR THE REST OF THE WEEK
WILL BE IN THE MID 20S IN THE AFTERNOON...WHICH WILL LEAD TO NEAR
NORMAL HIGHS. WHILE RAIN IS NOT ANTICIPATED THROUGH MOST OF THE WORK
WEEK...AT THIS POINT IT DOES NOT APPEAR FIRE WX WILL BE A CONCERN
NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 549 AM MDT THU JUL 11 2013
VFR CONDITIONS ARE EXPECTED FOR BOTH SITES AT THIS TIME. OVERNIGHT
THUNDERSTORMS HAS CAUSED THE WIND FIELD TO BECOME LIGHT AND
VARIABLE. SOME HEATING WILL HAVE TO TAKE PLACE BEFORE SOUTHERLY
WINDS INCREASE AND BECOME GUSTY. THIS GUSTINESS SHOULD LAST INTO
THE EVENING HOURS. UNCERTAIN THUNDERSTORM FORECAST DUE TO
MESOSCALE INFLUENCES OF OVERNIGHT CONVECTION. AT THIS TIME THE
GREATEST CHANCE OF THUNDERSTORMS WILL BE IN THE EAST. AT THIS TIME
CHOSE TO HANDLE THAT WITH VCTS AT KMCK.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...BULLER
LONG TERM...JJM
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS TOPEKA KS
642 AM CDT THU JUL 11 2013
...UPDATE FOR AVIATION AND SHORT TERM THUNDERSTORM FORECAST...
.UPDATE...
ISSUED AT 630 AM CDT THU JUL 11 2013
A VERY NARROW BAND OF MODERATE INSTABILITY APPEARS TO EXIST JUST
AHEAD OF A SHORT WAVE TROUGH MOVING INTO CENTRAL KANSAS. THE TIGHT
GRADIENT IN INSTABILITY SEEMS TO EXIST BETWEEN CONCORDIA WHERE
INSTABILITY IS MINIMAL AND SALINA WHERE RAP SOUNDINGS SUGGEST 1500
J/KG OF ELEVATED CAPE. SHORT TERM HI-RES MODELS SUGGEST THAT THE
WINDOW FOR THIS ELEVATED INSTABILITY IS FAIRLY SMALL NOT ONLY
SPATIALLY BUT ALSO IN TIME...AND WOULD EXPECT STORMS TO DIMINISH
IN COVERAGE AND INTENSITY THROUGH 9 AM. MAY SEE A FEW LINGERING
STORMS BEYOND 9 AM...BUT MOST INFORMATION POINTS TO DISSIPATION OF
ALL ACTIVITY BEFORE NOON. SO FAR...THE ONLY STORM TO POSE A SEVERE
RISK WAS OVER LINCOLN COUNTY IN A CELL THAT EXHIBITED MID LEVEL
ROTATION FOR 20 MINUTES OR SO AND INTENSIFIED ACCORDINGLY. THE
LIKELIHOOD OF THIS HAPPENING AGAIN IS LOW BUT NON-ZERO. ANY STRONG
STORMS WOULD POSE A RISK OF MARGINALLY SEVERE HAIL AND LOCALIZED
DOWNBURST WINDS AS THEY COLLAPSE. THE SLOW MOVEMENT OF THIS
ACTIVITY ALSO POINTS TO A LOCALIZED HEAVY RAINFALL POTENTIAL.
BARJENBRUCH
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM CDT THU JUL 11 2013
A WEAK SHORT WAVE TROUGH EVIDENT IN WV IMAGERY AND MID LEVEL WIND
PROFILES WAS MOVING TO THE SOUTHEAST OUT OF SOUTHWEST NEBRASKA AT 3
AM. SEVERAL CLUSTERS OF THUNDERSTORMS WERE ONGOING OVER THE HIGH
PLAINS IN CONJUNCTION WITH THIS SYSTEM BUT WILL REMAIN WELL WEST OF
THE LOCAL FORECAST AREA. EAST OF THIS SYSTEM...FAIRLY WEAK LOW LEVEL
SOUTHERLY FLOW WAS BEING PULLED INTO CENTRAL KANSAS...RESULTING IN
WEAK BUT DEEP ISENTROPIC ASCENT. THIS ASCENT WAS WORKING WITH WEAK
ELEVATED INSTABILITY TO SPARK ISOLATED SHOWERS IN NORTH CENTRAL
KANSAS. THE ASCENT...AND THUS THE ISOLATED SHOWER ACTIVITY...SHOULD
PERSIST OVER NORTH CENTRAL KANSAS INTO THE MID MORNING HOURS WITH AN
OUTSIDE CHANCE FOR A FEW LIGHTNING STRIKES AS WELL ALTHOUGH THE
STRONGER INSTABILITY SEEMS TO BE WEST OF THE FORECAST AREA. ANY
PRECIP IS EXPECTED TO COME TO AN END BY NOON...WITH DRY CONDITIONS
EXPECTED THROUGH THE REST OF TODAY AND TONIGHT. TEMPERATURES SHOULD
WARM UP NICELY AGAIN TODAY AFTER MORNING LOWS IN THE UPPER 60S...AND
EXPECT HIGHS IN THE UPPER 80S TO LOWER 90S. MOSTLY CLEAR SKIES WILL
ALLOW A QUICK COOL DOWN THIS EVENING...AND WHILE A SOUTH BREEZE
SHOULD KEEP NORTH CENTRAL KANSAS IN THE UPPER 60S TO LOWER
70S...LIGHTER WINDS IN EASTERN KANSAS SHOULD CONTRIBUTE TO LOW TEMPS
IN THE MIDDLE 60S.
BARJENBRUCH
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 333 AM CDT THU JUL 11 2013
MAIN MID LEVEL FEATURE BEING THE EXPANSIVE MID LEVEL RIDGE OVER THE
SOUTHWEST CONUS IS EXPECTED TO FINALLY MIGRATE EAST AS AN UPPER
SHORTWAVE TROUGH SETTLES AND BECOMES CUTOFF FROM THE MAIN FLOW
THROUGH THE WEEKEND. LATEST GFS TRIES TO BRING IN SOME SPOTTED
QPF TOWARDS THE NORTH CENTRAL AREAS ON FRIDAY MORNING...HOWEVER
WITH NO CLEAR LACK OF FORCING HAVE DECIDED TO LEAVE DRY AT THIS
TIME. MAIN STORY THEN TURNS TO THE HEAT AS A SURFACE TROUGH
SITUATED OVER EASTERN COLORADO WILL PROVIDE DECENT SOUTHWEST FLOW
AND AMPLE WARM ADVECTION. KEPT TRENDS IN PLACE WITH WARMEST HIGHS
FRIDAY NEAR 100 DEGREES OVER NORTH CENTRAL KS COINCIDING WITH
PROXIMITY OF THERMAL AXIS. SLIGHTLY COOLER TEMPS IN THE LOW 90S
EXPECTED FOR THE EAST CENTRAL/NORTHEAST AREAS...HOWEVER WITH
DEWPOINT VALUES IN THE 60S ADVECTING INTO THE AREA WILL MAKE IT
FEEL NEAR THE CENTURY MARK OR A FEW DEGREES HIGHER FRIDAY INTO
SATURDAY. LITTLE CHANGE OCCURS FOR SATURDAY EXCEPT WARM LOWS
SATURDAY MORNING IN THE 70S WILL ALLOW TEMPS ONCE AGAIN TO RISE TO
THE CENTURY MARK OVER NORTH CENTRAL KS. NOTING TRENDS AND
PERFORMANCE OF THE GFS AND NAM MOS GUIDANCE LEAD TO GOING A FEW
DEGREES ABOVE OUTPUT FOR HIGHS ON FRIDAY/SATURDAY.
UNCERTAINTY INCREASES STEADILY AS WE HEAD INTO THE EXTENDED PERIOD.
LATEST RUNS OF THE GFS/ECMWF PUSH THE H5 RIDGE BACK WEST AS THE
CLOSED TROUGH OVER THE NORTHEAST CONUS RETROGRADES WESTWARD
INFLUENCED BY ANOTHER RIDGE BUILDING OVER THE ATLANTIC. POSITION AND
WESTERN EXTENT OF THIS TROUGH MAY MEAN THE DIFFERENCE BETWEEN A VERY
WET OR DRY PERIOD. IF THE CURRENT GFS/ECMWF CAME TO FRUITION WE MAY
SEE PERIODS OF SHOWERS AND THUNDERSTORMS THROUGHOUT NEXT
WEEK...GREATLY IMPACTING THE TEMPERATURES IN CURRENT FORECAST. SINCE
THIS SCENARIO HAS NOT BEEN CONSISTENT WITH RECENT SOLUTIONS WILL
KEEP A DRY FORECAST FOR NOW ASSUMING THE RIDGE INFLUENCES THE AREA
WITH THE TROUGH POSITIONED FURTHER EAST. WILL MONITOR IN THE
UPCOMING FORECASTS AND MAKE CHANGES IF NEEDED. SURFACE HIGH PRESSURE
IN PLACE WILL KEEP TEMPERATURES NEAR THE NORMAL VALUES IN THE LOW TO
MID 90S FOR HIGHS AND LOWS IN THE UPPER 60S TO LOW 70S THROUGH
THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT
630 AM CDT WED JUL 10 2013
VFR CONDITIONS ARE FORECAST THROUGH THE TAF PERIOD AT ALL SITES.
EAST WINDS MAY GUST A BIT DURING THE LATE MORNING HOURS BUT ANY
GUSTS SHOULD EVEN BE BELOW 18 KTS AND SHORT LIVED. MHK HAS A VERY
SMALL CHANCE FOR ISOLATED TS AFFECTING TAF SITE THROUGH 16Z...BUT
NOT A GOOD ENOUGH CHANCE TO MENTION IN THE TAF.
BARJENBRUCH
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BARJENBRUCH
SHORT TERM...BARJENBRUCH
LONG TERM...BOWEN
AVIATION...BARJENBRUCH
AREA FORECAST DISCUSSION
NWS WICHITA KS
637 AM CDT THU JUL 11 2013
...AVIATION UPDATE...
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 400 AM CDT THU JUL 11 2013
TODAY:
(+)TSRA CLUSTER CONTINUES OVER SW NEBRASKA/NW KS BORDER FROM ~KMCK SE
OVER DECATUR & NORTON COUNTIES. ANOTHER (+)TSRA THAT DEVELOPED OVER
ERN OSBORNE COUNTY IS STATIONARY. TSRA BEING SUSTAINED BY STRONG DEEP
ISENTROPIC ASCENT FROM 305-315K LAYER INDUCED BY BROAD HIGH PRESSURE
COVERING MOST OF UPR MS VALLEY & WEAK LOW PRESSURE SITUATED NEAR CO/KS
BORDER...FROM WHICH A WEAK NEARLY STATIONARY FRONT EXTENDS SE ACROSS
SW KS TO NRN OK. WELL-DEFINED RICH LWR-DECK MOISTURE AXIS IS ORIENTED
IN NW-SE MANNER ALONG & JUST NE OF THE BOUNDARY TO ALONG THE W/SW
CORRIDOR OF KICT COUNTRY. GREATEST CHANCES FOR TSRA TO THEREFORE OCCUR
OVER WRN HALF OF KICT COUNTRY THIS MORNING. HRRR DEPICTING A SIMILAR
PATTERN & AS SUCH HAVE INCREASED POPS TO 35-40% OVER THAT PART OF
CNTRL KS W OF I-135. AS LWR-DECK TROFFING GETS BETTER ESTABLISHED LWR
DECK FLOW TO BECOME MORE SLY WHICH WOULD REALIGN LWR-DECK MOISTURE
AXIS TO N-S ORIENTATION. WITH STRONG MASSIVE MID-UPR HIGH INCREASING
DOMINANCE FROM THE SRN TOWARD THE NRN PLAINS THE RESULTING INCREASED
SUBSIDENCE WOULD INHIBIT FURTHER TSRA DEVELOPMENT THIS AFTERNOON.
THE ALREADY STRONG MASSIVE HIGH PRESSURE BECOMES EVEN MORE SO OVER THE
NEXT 3 DAYS & WITH LWR-DECK TROFFING INCRESING OVER THE WRN PLAINS THE
FURNACE WILL REMAIN TURNED UP THRU SATURDAY. HIGHS ~100F ARE LIKELY
ALONG THE WRN CORRIDOR FRI & SAT WHERE HEAT INDICES ~105F ARE POSSIBLE.
AS SUCH A HEAT ADVISORY MAY BE REQUIRED...ESPECIALLY FRI. STAY TUNED.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 355 AM CDT THU JUL 11 2013
TYPICAL MID-SUMMER STILL ANTICIPATED THROUGHOUT THESE PERIODS. HOWEVER
MID-RANGE MODELS (MORE SO THE GFS) DEPICT A MID-UPR LOW PRESSURE AREA
RETROGRADING ACROSS THE MID-MS VALLEY TOWARD...THEN ACROSS...THE MO/KS
BORDER ON MON. FOR NOW HAVE DRY FORECAST INTACT BUT THE BEHAVIOR OF THE
UNORTHODOX LOW WILL REQUIRE INCREASED ATTENTION LATER THIS WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 634 AM CDT THU JUL 11 2013
SCATTERED STRONG CONVECTION WILL AFFECT PORTIONS OF CENTRAL AND
SOUTH CENTRAL KANSAS THIS MORNING. OTHERWISE VFR CONDITIONS ARE
EXPECTED FOR THE REMAINDER OF THE FORECAST VALID PERIOD. WINDS
WILL GRADUALLY VEER MORE TO THE SOUTHEAST AND BECOME OCCASIONALLY
GUSTY ACROSS CENTRAL KANSAS THIS AFTERNOON AND EVENING.
KED
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 97 72 99 77 / 30 0 0 0
HUTCHINSON 96 72 100 77 / 40 0 0 0
NEWTON 94 71 97 76 / 30 0 0 0
ELDORADO 93 71 97 75 / 20 0 0 0
WINFIELD-KWLD 96 73 99 76 / 30 0 0 0
RUSSELL 95 72 102 77 / 40 10 0 0
GREAT BEND 96 73 102 77 / 40 10 0 0
SALINA 93 72 101 77 / 30 10 0 0
MCPHERSON 94 72 100 77 / 40 0 0 0
COFFEYVILLE 92 71 97 73 / 10 0 0 0
CHANUTE 89 69 95 71 / 10 0 0 0
IOLA 90 68 94 71 / 10 0 0 0
PARSONS-KPPF 91 70 95 72 / 10 0 0 0
&&
.ICT WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
415 AM MDT THU JUL 11 2013
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 415 AM MDT THU JUL 11 2013
FORECAST CONCERNS WILL BE CHANCE OF THUNDERSTORMS FOLLOWED BY HOW
HOT DOES IT GET ALONG WITH POSSIBLE HEAT HIGHLIGHTS. SATELLITE
SHOWING A RATHER AMPLIFIED PATTERN FROM THE PACIFIC IN CENTRAL NORTH
AMERICA. MOISTURE AND WEAK SHORTWAVE TROUGHS ROTATING AROUND UPPER
HIGH CENTERED TO OUR SOUTH/SOUTHWEST. FRONTAL BOUNDARY AT THIS TIME
REMAINS DRAPED TO OUR SOUTH AND WEST.
AT MID LEVELS...THE UKMET FOLLOWED BY THE CANADIAN AND GFS WERE
DOING BEST ON WHERE THE CENTER OF THE MID/UPPER HIGH WAS AND THE
RESULTING HEIGHT FIELD OVER THE AREA. OUTFLOW BOUNDARIES ARE
MESSING UP THE WIND FIELD RIGHT AND THE HRRR HAS THE RIGHT IDEA ON
IT. UKMET AND CANADIAN WERE DOING A LITTLE BETTER THAN THE GFS AND
ECMWF ON THE LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...HOW MUCH THUNDERSTORM ACTIVITY WILL BE AROUND THIS
MORNING AND LINGERING MESOSCALE AFFECTS FROM THESE THUNDERSTORMS WILL
BE AROUND FOR THE ENTIRE DAY ARE THE BIG QUESTIONS WHICH MAY BE VERY
HARD TO ANSWER. PERSISTENT CLUSTER OF THUNDERSTORMS REMAINS OVER THE
EASTERN PORTION OF THE AREA. THIS AREA WAS THE RESULT A WEAK
SHORTWAVE IN THE AREA BUT MOST OF ALL THE COLLISION OF OUTFLOW
BOUNDARIES. OUTFLOW BOUNDARIES ABOUND ACROSS THE AREA PER RADAR AND
SURFACE OBSERVATIONS AND ESPECIALLY IN THE EASTERN AND CENTRAL
PORTION. ELEVATED CAPE AND LACK OF STRONG ELEVATED CINH WILL BE
AROUND AT THE BEGINNING OF THE DAY. ADDITIONAL DEVELOPMENT IS
OCCURRING AND IS EXPECTED TO CONTINUE TO OCCUR. SO ISSUED THE ZONES
WITH A PRE-FIRST PERIOD AND KEPT POPS AROUND IN THE MORNING...
ESPECIALLY IN THE EAST. WILL CONTINUE TO MONITOR AND WILL ISSUE AN
UPDATE NEAR 12Z TO ACCOUNT FOR THE LATEST TRENDS WHICH THE MODELS ARE
PLAYING CATCH UP WITH.
NOT ACCOUNTING FOR MESOSCALE INFLUENCES OVERNIGHT GUIDANCE HAD THE
HIGHEST INSTABILITY AND LOWEST 700 MB TEMPERATURES IN THE EASTERN
PORTION OF THE AREA. AT 500 MB WEAK SHORTWAVE IS MOVING ACROSS THE
EASTERN HALF IN THE AFTERNOON. AT 700 MB A SHORTWAVE TROUGH BEGINS
TO AFFECT THE WESTERN PORTION BUT THE 700 MB TEMPERATURES ARE MUCH
WARMER. SATELLITE WOULD ALSO INDICATE ANOTHER INFLUX OF MID LEVEL
SUBTROPICAL MOISTURE FROM THE WEST. AND THE BIGGEST VARIABLE IS
WHERE WILL THERE BE LEFTOVER OUTFLOW BOUNDARIES. WOULD SAY THERE IS
A GOOD PROBABILITY OF ONE OR MORE IN THE CENTRAL AND EASTERN PORTION
OF THE AREA. SO TO ACCOUNT FOR THIS...PUT SLIGHT CHANCE IN THE WEST
AND LOW CHANCE IN THE EAST.
DEPENDING ON HOW PERSISTENT THE CONVECTION STAYS...HOW MUCH CLOUD
COVER HANGS AROUND...AND HOW SIGNIFICANT THE OUTFLOW IS...HIGH
TEMPERATURES MAY BE SEVERELY AFFECTED. BELIEVE THIS CONVECTION WILL
ALSO KEEP THE SYNOPTIC FRONT SUPPRESSED FURTHER TO THE SOUTH AND
WEST. KEPT THE COOLEST EAST AND THE WARMEST WEST BUT THAT IS HIGHLY
PROBLEMATIC AT THIS POINT.
FRIDAY/FRIDAY NIGHT...IN REGARDS TO THE PRECIPITATION...NEWEST MODEL
GUIDANCE SUPPORTS THE PREVIOUS FORECAST VERY WELL. RIDGE STARTS
BUILDING INTO THE AREA BUT THE MODELS DISAGREE ON HOW MUCH. MID
LEVEL TEMPERATURES WARM AND IT DOES LOOK LIKE MOST OF THE FORECAST
AREA EAST OF THE COLORADO BORDER DOES STAY CAPPED. A SURFACE TROUGH
SUPPLYING LOW LEVEL CONVERGENCE ALONG WITH A WEAK SHORTWAVE AFFECT
THE FAR WESTERN PORTION OF THE AREA WHICH IS WHERE THE 700 MB
TEMPERATURES ARE THE WARMEST. SO MADE LITTLE IF ANY CHANGE TO THE
PRECIPITATION FORECAST. NEW GUIDANCE SUPPORTS WARMING UP NOT ONLY
MAXES BUT THE MINS AS WELL. MOST OF THE AREA SHOULD BE ABOVE 100
DEGREES WITH THE EASTERN HALF THE HOTTEST FOR THE MAXES.
THIS COULD BE THE BEGINNING OF AN EXTENDED HEAT HIGHLIGHT FOR THE
EASTERN PORTION OF THE AREA. HEAT INDICES IN THE AFTERNOON REACH
105 IN THE EASTERN SIX COUNTIES DURING THE DAY. THEN OVERNIGHT MINS
DO NOT DROP OFF VERY MUCH AND I ACTUALLY MAY BE TOO COOL.
SATURDAY/SATURDAY NIGHT...SIMILAR SCENARIO FOR PRECIPITATION THESE
TWO PERIODS AS THE PREVIOUS TWO. THE MID/UPPER RIDGE LOOKS TO BUILD
IN MORE WITH HIGHER 700 MB TEMPERATURES AND ALSO LESS SURFACE
CONVERGENCE NEAR THE WESTERN END OF THE FORECAST AREA. WEAK LIFT IN
ADDITION TO THE EXTREME HEATING...COULD HELP SET OFF A FEW
THUNDERSTORMS. ALMOST CANNOT HELP BUT INITIATE THUNDERSTORMS IN
THIS KIND OF HEATING. CURRENT FORECAST HAD THIS SCENARIO WELL IN
HAND AND DID NOT CHANGE ANYTHING. MODELS LOOK TO INCREASE THE HEAT.
IT IS POSSIBLE I STILL DO NOT HAVE THE MAXES HOT ENOUGH...ESPECIALLY
IN THE EASTERN HALF. MINS LOOKS JUST AS WARM OR WARMER THAN THE
PREVIOUS NIGHT.
HEAT INDICES OF 105 PUSH ONE ROW OF COUNTIES FURTHER WEST THAN THE
PREVIOUS DAY. AM NOT ISSUING A HEAT HIGHLIGHT YET...BUT PLAN ON
MENTIONING THE FRIDAY INTO SATURDAY NIGHT PERIOD IN THE HWO.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 415 AM MDT THU JUL 11 2013
A LARGER THAN NORMAL DEGREE OF UNCERTAINTY IN THE EXTENDED
ON THE SYNOPTIC SCALE...THOUGH MOST SOLUTIONS END UP WITH SIMILAR
CONDITIONS FOR THE HIGH PLAINS. MAIN STORY EARLY NEXT WEEK WILL BE
HIGHS NEAR TO SLIGHTLY ABOVE NORMAL WITH GENERALLY DRY CONDITIONS.
ON SUNDAY A WEAK UPPER LEVEL DISTURBANCE MOVES ACROSS THE CENTRAL
ROCKIES AND INTO THE HIGH PLAINS...WHICH COULD HELP TO DEVELOP A FEW
SHOWERS/STORMS ON SUNDAY AFTERNOON INTO THE EVENING. TEMPS WILL BE
WARMEST ON SUNDAY WITH 850 TEMPS IN THE MID TO UPPER 20S...THOUGH
THE EC IS AN OUTLIER WITH SLIGHTLY COOLER TEMPS. THE REST OF THEE
WEEK MOST DETERMINISTIC GUIDANCE SHOWS AN UPPER LOW OVER MID-WEST
AND MOVING WEST AS IT WEAKENS...THOUGH AT THIS POINT BELIEVE THE
UPPER LOW WILL REMAIN FARTHER EAST AND AN UPPER RIDGE WILL BE OVER
HIGH PLAINS KEEPING THINGS DRY. 850 TEMPS FOR THE REST OF THE WEEK
WILL BE IN THE MID 20S IN THE AFTERNOON...WHICH WILL LEAD TO NEAR
NORMAL HIGHS. WHILE RAIN IS NOT ANTICIPATED THROUGH MOST OF THE WORK
WEEK...AT THIS POINT IT DOES NOT APPEAR FIRE WX WILL BE A CONCERN
NEXT WEEK.
&&
.AVIATION....(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 413 AM MDT THU JUL 11 2013
THUNDERSTORMS WILL BE NEAR KMCK THROUGH 12Z AND LATEST AMENDMENT
TAKES CARE OF THIS. THUNDERSTORM DEVELOPMENT IS EXPECTED TO BE
FURTHER EAST THIS AFTERNOON AND COULD AFFECT THE KMCK SITE. THIS
WILL BE ADDRESSED IN THE NEXT TAF ISSUANCE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...JJM
AVIATION...BULLER
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1028 AM EDT THU JUL 11 2013
.UPDATE...
ISSUED AT 1025 AM EDT THU JUL 11 2013
A COLD FRONT CONTINUES TO SAG SOUTH AND EAST ACROSS THE OH VALLEY
REGION AND EASTERN KY. THERE IS MAINLY LOW CLOUDS AND STRATUS LEFT
FROM EARLIER FOG AND RECENT RADAR IMAGERY SUGGESTS SOME SPRINKLES OR
LIGHT SHOWERS AND SOME DRIZZLE WITH THIS ATTM. RECENT 12Z NAM
GUIDANCE AS WELL AS THE 9Z SREF SUGGEST THE POTENTIAL FOR SOME MAINLY
AFTERNOON CONVECTION IN THE SOUTHEAST CWA. THE HRRR HAS SOME
CONVECTIVE ACTIVITY AS WELL...BUT SEEMS TO HAVE IT TOO FAR TO THE
NORTHWEST.
OVERALL...PERSISTENCE AND RECENT MODEL GUIDANCE SUGGESTS THAT
ISOLATED TO SCATTERED SHRA/TSRA ARE POSSIBLE DURING PEAK HEATING
TODAY AS THE BOUNDARY SLOWLY SAGS SOUTHEAST TOWARD THE VA BORDER.
OTHER THAN FRESHENING UP THE FORECAST BASED ON RECENT OBSERVATIONS...
NO SIGNIFICANT CHANGES WERE MADE.
UPDATE ISSUED AT 737 AM EDT THU JUL 11 2013
BASED ON AMOUNT OF FOG ACROSS MUCH OF THE AREA...UPDATED TO INCLUDE
DENSE FOG WORDING IN THE GRIDS. WITH LLVL INVERSION AND FOG STILL IN
PLACE...THERE HAS BEEN NO CONVECTIVE DEVELOPMENT SO FAR THIS MORNING.
SOME ISL/SCT SHOWERS ARE STILL POSSIBLE AS THE FRONT PASSES THROUGH
LATE THIS MORNING/EARLY THIS AFTERNOON...BUT SO LONG AS FOG AND
INVERSION ARE IN PLACE...POPS WILL BE LIMITED. WENT AHEAD AND BUMPED
DOWN POPS SLIGHTLY TO TAKE OUT ONGOING SCT WORDING THIS
MORNING...WITH BETTER CHANCES MOVING IN FROM PIKE TO MCCREARY COUNTY
OVER THE NEXT FEW HOURS HOPEFULLY AS FOG AND INVERSION BEGIN TO LIFT.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 340 AM EDT THU JUL 11 2013
AFTER A VERY EVENTFUL WEEK...IT SEEMS AS THOUGH QUIETER AND NICER
WEATHER IS FINALLY IN STORE. COLD FRONT WILL CONTINUE TO PUSH
THROUGH SE KY THIS MORNING...BUT MAIN AREA OF CONVECTION AHEAD OF
THE FRONT HAS MOVED OUT OF THE REGION WITH AN ABUNDANT AMOUNT OF
DRY AIR NOW FILTERING IN. A FEW ISOLATED SHALLOW AND SHORT LIVED
SHOWERS COULD BE POSSIBLE AS THE FRONT PASSES THROUGH IN THE LATE
MORNING/EARLY AFTERNOON...BUT LITTLE IS EXPECTED FOR IMPACTS. BACKED
OFF ON POPS BOTH FOR THE OVERNIGHT LAST NIGHT AND INTO THE DAY TODAY
AS A RESULT. MAIN CONCERN RIGHT NOW IS THE FACT THAT DESPITE ALL OF
THIS DRY AIR IN PLACE...RAIN THAT TRAVERSED THE REGION YESTERDAY HAS
LED TO VERY MOIST LLVLS TRAPPED BELOW A NEAR SURFACE INVERSION. AS A
RESULT...FAIRLY DENSE AND WIDESPREAD FOG STARTED FORMING LAST
NIGHT...AND WILL CONTINUE THROUGHOUT THE MORNING HOURS BEFORE SURFACE
INVERSION CLIMBS A LITTLE HIGHER UP IN THE ATMOSPHERE. AT THIS
POINT...FOG WILL LIFT INTO A LLVL STRATUS DECK AND
THEN EVENTUALLY A BROKEN CU DECK BEFORE IT SCATTERS OFF IN THE
EVENING. IT IS ALSO IN THIS LAYER THAT WE WILL SEE OUR BEST
POTENTIAL FOR ANY ABOVE MENTIONED LIGHT CONVECTIVE DEVELOPMENT. IN
GOOD NEWS...THIS DECK WILL BE FAIRLY SHALLOW WITH THE POTENTIAL TO
BREAK DOWN EVEN SOONER VIA ANY DAYTIME MODIFICATION TO THE SOUNDING.
OTHERWISE...PLAN ON GREAT WEATHER TODAY. HIGH TEMPERATURES WILL
BE BELOW NORMAL ACROSS THE REGION...REACHING NEAR 80 IN MOST
LOCATIONS WITH WINDS COMING FROM A NRLY DIRECTION. AND WITH A DRIER
CONTINENTAL AIRMASS IN PLACE...EXPECT HUMIDITY LEVELS TO BE MUCH
LOWER THAN PREVIOUS DAYS. THE SAME WILL CARRY OVER INTO THE
OVERNIGHT HOURS AND INTO THE DAY TOMORROW. SOME PATCHY FOG WILL BE
POSSIBLE OVERNIGHT TONIGHT...BUT SHOULD MAINLY BE LIGHT AND CONFINED
TO THE EXTREME VALLEYS WHERE INVERSION IS MORE LIKELY TO SET UP. DRY
AIRMASS WILL PREVENT A REPEAT FROM LAST NIGHT/THIS MORNING.
OTHERWISE...ENJOY. HIGH PRESSURE AND DRY/MILD WEATHER SHOULD CARRY
OVER INTO THE WEEKEND.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 340 AM EDT THU JUL 11 2013
THERE IS STILL GOOD AGREEMENT IN THE MODELS EARLY ON...BUT NOT FAR
INTO THE PERIOD THEIR SOLUTIONS BEGIN TO DIVERGE. THE ELEMENT IN
DISPUTE IS AN UPPER LOW WHICH WILL BE LEFT BEHIND BY THE TROUGH
CURRENTLY DROPPING INTO THE EASTERN CONUS. MODELS DO AGREE ON A
CLOSED LOW BEING PINCHED OFF NEAR THE WV/MD BORDER BY FRIDAY
EVENING. THIS LOW THEN RETROGRADES...BUT EXACTLY WHERE IT GOES AND
HOW FAST IT MOVES ARE IN QUESTION. WITHOUT A CLEAR PREFERENCE...WILL
USE A BLENDED MODEL SOLUTION.
AT THE SURFACE...OUR INITIAL AIR MASS WILL BE DRY...HAVING BEEN
SUPPLIED BY HIGH PRESSURE OVER THE GREAT LAKES. THIS HIGH WILL
WEAKEN AND SUBTROPICAL HIGH PRESSURE OVER THE ATLANTIC WILL BECOME
MORE DOMINANT. IT WILL SEND A MORE HUMID AIR MASS BACK NORTHWEST
OVER THE LOCAL AREA...UNDERNEATH THE WEAK TROUGH OR UPPER LOW LEFT
BEHIND. THIS WILL RESULT IN A POSSIBILITY OF SHOWERS/THUNDERSTORMS
BY LATE SATURDAY NIGHT OR SUNDAY. THE BEST CHANCE WILL BE MONDAY AND
TUESDAY. BY WEDNESDAY...MODELS SHOW WHAT IS LEFT OF THE UPPER LOW TO
BE WELL TO OUR WEST OR SOUTHWEST...WITH UPPER LEVEL RIDGING BUILDING
OVER THE OHIO VALLEY...CUTTING INTO POPS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 704 AM EDT THU JUL 11 2013
A LINE OF SHOWERS AND THUNDERSTORMS MOVED THROUGH THE AREA YESTERDAY
AFTERNOON/EVENING AHEAD OF AN APPROACHING SURFACE COLD FRONT...BEFORE
EXITING THE REGION BY LATE EVENING. AS SUCH...DRY AIR HAS NOW
FILTERED IN BEHIND THE CONVECTION...BUT A LLVL INVERSION THAT
DEVELOPED OVERNIGHT HAS TRAPPED A LARGE AMOUNT OF MOISTURE NEAR THE
SURFACE. THIS HAS CAUSED FOG TO DEVELOP AND AFFECT MUCH OF THE
REGION...INCLUDING ALL THREE TAF SITES...CAUSING THEM TO FALL BELOW
AIRPORT MINIMUMS. FORECAST SOUNDINGS POINT AT THIS FOG STICKING
AROUND THROUGH MID MORNING...THEN AS SURFACE FRONT APPROACHES...BEST
MOISTURE WILL LIFT FROM THE SURFACE TO CREATE A LLVL STRATUS DECK AND
THEN EVENTUALLY A BROKEN CU DECK BEFORE IT SCATTERS OFF IN THE
EVENING. DRY AIRMASS IN PLACE THIS AFTERNOON AND TONIGHT SHOULD
PREVENT ANY WIDESPREAD DEVELOPMENT OF FOG...SO DO NOT EXPECT ANY
IMPACTS AT TAF SITES.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...JMW
LONG TERM...HAL
AVIATION...JMW
AREA FORECAST DISCUSSION
NWS GLASGOW MT
938 AM MDT THU JUL 11 2013
.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH SATURDAY...
UPDATE...
SHORT TERM FORECAST LOOKS TO BE ON TRACK. STILL EXPECTING A RATHER
HOT DAY ACROSS THE CWA WITH TEMPERATURES SOARING WELL INTO THE
90S. POTENTIAL EXISTS FOR A FEW LOCATIONS TO EXCEED 100 DEGREES IN
THE YELLOWSTONE VALLEY AND IN SOUTHEASTERN PORTIONS OF THE
FORECAST AREA WHERE 850MB TEMPERATURES ARE EXPECTED TO BE A COUPLE
OF DEGREES WARMER THIS AFTERNOON. GIVEN INCREASED CLOUD COVER INTO
THE WESTERN ZONES THIS AFTERNOON AND EARLIER PASSAGE OF THE
FRONT...WENT AHEAD AND NUDGED HIGHS DOWN JUST A BIT IN THOSE LOCATIONS.
OTHERWISE THE MAIN FOCUS WAS ON THE SEVERE WEATHER POTENTIAL IN
THE EASTERN ZONES. AS THE RIDGE AXIS PASSES EAST...NORTHEAST
MONTANA WILL ENTER INTO A REGIME OF SOUTHWEST FLOW ALOFT AND AN
ENHANCED REGION OF FAVORED VERTICAL ASCENT OUT AHEAD OF AN
APPROACHING UPPER LEVEL SHORTWAVE. WITH FRONTAL PASSAGE FURTHER
FORCING LIFT...AND INVERTED-V SOUNDINGS PRESENT...EXPECT ANY
STORMS THAT DEVELOP TO BE CAPABLE OF STRONG WIND GUSTS. CANNOT
RULE OUT POTENTIAL FOR HAIL. HEAVY RAIN MAY BE KEPT AT A MINIMUM
GIVEN SUCH DRY LOW LEVELS. ANY DOWNDRAFTS THOUGH MAY BE
ACCELERATED THROUGH EVAPORATIVE COOLING IN THE DRIER LOW LEVELS.
WILL NEED TO WATCH THE SIDNEY TO GLENDIVE AREA IN PARTICULAR THIS
AFTERNOON GIVEN AGREEMENT WITH THE SPC STORM SCALE ENSEMBLE OF
OPPORTUNITY PRODUCT ALONG WITH RECENT HRRR AND NAM SOLUTIONS. THIS
IS ALSO WHERE THE HIGHEST CAPE AND MORE FAVORABLE LIFTED INDEX
VALUES LOOK TO BE FOR THIS AFTERNOON AND EVENING. MALIAWCO
PREVIOUS SHORT TERM DISCUSSION...
UPPER RIDGE AXIS EXPECTED TO MOVE INTO THE DAKOTAS TODAY WITH
SHORTWAVE LIFTING OUT OF THE GREAT BASIN. STRONG THERMAL RIDGE
WILL PUSH TEMPERATURES CLOSE TO 100 THIS AFTERNOON...PARTICULARLY
OVER THE SOUTHEAST ZONES IN ADVANCE OF THE SHORTWAVE.
SOUTHEAST LOW LEVEL FLOW WILL BE STRENGTHENING INTO THE NORTHERN PLAINS
BRINGING GULF MOISTURE INTO THE REGION AND INTENSIFYING THE LEE TROF
OVER CENTRAL MONTANA. AS THE SHORTWAVE PUSHES THIS TROF/FRONT EASTWARD
THIS AFTERNOON COULD SEE CONVECTIVE DEVELOPMENT AS THE FRONT
ENCOUNTERS GREATER INSTABILITY OVER THE EASTERN ZONES. ALTHOUGH
BOUNDARY LAYER DEW POINTS INTO THE 60S ARE ANTICIPATED...VERY HOT
SURFACE TEMPERATURES AND DRY MID LEVELS WILL RESULT IN INVERTED V
SOUNDINGS WITH A HIGH LCL. HIGH BASED STORMS WILL LITTLE
PRECIPITATION AND STRONG WIND GUSTS ARE EXPECTED AND SOME COULD BE
SEVERE NEAR THE NORTH DAKOTA BORDER LATE THIS AFTERNOON AND INTO
THE EVENING.
TEMPERATURES CLOSER TO NORMAL EXPECTED ON FRIDAY AND SATURDAY.
TROF ALONG THE WESTERN CANADIAN COAST WILL SWING A SHORTWAVE EAST
ALONG THE INTERNATIONAL BORDER FRIDAY NIGHT INTO SATURDAY...ALONG
WITH ANOTHER FRONTAL SYSTEM. THUNDERSTORMS ARE AGAIN EXPECTED
WITH THIS SYSTEM. EBERT
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY...
SYNOPTIC SET UP... LONG TERM BEGINS WITH A LARGE HEAT DOME
STRETCHED OVER THE CENTRAL AND SOUTHERN US PLAINS AND FOUR CORNERS
REGION. A CLOSED LOW EXISTS OVER THE NORTHWEST TERRITORIES WITH A
TROUGH JUTTING OFF OVER NORTHERN ALBERTA AND BRITISH COLUMBIA.
NORTHEAST MONTANA LIES IN BETWEEN THESE TWO FEATURES OF FLUCTUATING
ZONAL ALOFT ALL THE WAY BACK TO OFF THE COAST OF THE PACIFIC
NORTHWEST.
SATURDAY NIGHT THROUGH MONDAY... FLOW WILL TILT SLIGHTLY SOUTHWEST
AND ALLOW A FEW SHORTWAVES TO PASS THROUGH NORTHEAST MONTANA ALONG
WITH PACIFIC MOISTURE. TIMING OF ANY PARTICULAR WAVE IS DIFFICULT
AND WASHED OUT. HOWEVER... THE EASTERN HALF OF THE CWA APPEARS TO
HAVE HIGHER CHANCES FOR POPS AS MOISTURE IS EXPECTED TO INCREASE
TO THE EAST NEAR THE SURFACE.
MONDAY NIGHT THROUGH WEDNESDAY... THE HEAT DOME OVER THE WESTERN
HALF OF THE US WILL EXTEND A RIDGE UP THROUGH THE THE PACIFIC
NORTHWEST AND BRITISH COLUMBIA. THE RIDGE IS WEAK... SO SHORTWAVES
COULD STILL BREAK THROUGH... BUT IT IS ANTICIPATED TO SUBTLY TILT
FLOW TO THE NORTHWEST WITH DRIER MID LEVELS. A SEMI-PERMANENT LEE
SURFACE TROUGH WILL SET UP DURING THESE PERIODS AND BE A FOCAL
POINT FOR ANY AFTERNOON STORM DEVELOPMENT. TIMING OF WAVES DURING
THIS PERIOD IS RATHER DIFFICULT HOWEVER. EXPECT A WARMING TREND AS
THE RIDGE BUILDS TO THE WEST AND INCREASES INFLUENCE.
WEDNESDAY NIGHT ONWARD... MODELS ARE HINTING AT A TROUGH DROPPING
SOUTH OF THE GULF OF ALASKA TO OFF THE COAST OF THE PACIFIC
NORTHWEST. THIS WILL NUDGE THE BUILDING HEAT DOME OVER THE
INTERMOUNTAIN WEST EAST... INCREASING THE INFLUENCE OVER NORTHEAST
MONTANA AND TRENDING WARMER AND DRIER WEATHER OVERALL. GAH
&&
.AVIATION...
FLIGHT CATEGORY:
MOSTLY VFR WITH LOWER CONDITIONS POSSIBLE. AMENDMENTS MAY BE
NEEDED FOR THUNDER LATER TODAY.
IMPACTS:
SHOWERS AND THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND
EVENING...ESPECIALLY AT KSDY AND KGDV. TEMPORARY REDUCTIONS IN
FLIGHT CONDITIONS CAN BE EXPECTED. THESE TERMINALS WILL ALSO WANT
TO BE AWARE OF STRONG VERTICAL WIND SHEAR DURING THE AFTERNOON AND
EVENING HOURS WHICH COULD COMPLICATE GROUND OPERATIONS. THIS MAY
RESULT IN STRONG GUSTY WINDS...ESPECIALLY IN OR NEAR
THUNDERSTORMS. BRIEF FUEL LOADING CONDITIONS ARE POSSIBLE WITH
STORMS.
AREA WINDS:
SOUTHWEST 5 TO 10 KTS EARLY THIS MORNING INCREASING TO 10 TO 20
KTS SUSTAINED WITH POSSIBLE GUSTS NEAR 30KTS FOR KSDY AND KGDV
BEGINNING EARLY THIS AFTERNOON. WINDS WILL VEER TO THE WEST AND
NORTHWEST BEHIND A COLD FRONT LATER THIS AFTERNOON.
GAH/BLM
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
902 AM MDT THU JUL 11 2013
.UPDATE...
MADE A FEW ADJUSTMENTS TO POPS TODAY THROUGH THIS EVENING. STREAM
OF VORTICITY WILL MOVE NE INTO THE WESTERN ZONES TODAY THROUGH
THIS EVENING BRINGING A SLIGHT CHANCE OF THUNDERSTORMS. SOUNDINGS
WERE DRY IN THE LOW-LEVELS BUT HAD A WET MICROBURST APPEARANCE
OVERALL. SPREAD THE SLIGHT CHANCE INTO KBIL THIS AFTERNOON AND
EVENING. DESPITE WARM 700 MB AIRMASS...SOUNDINGS HAD LITTLE IF ANY
CAP OVER KBIL. FURTHER E...CAP LOOKED MUCH STRONGER UNTIL THE FAR
SE ZONES WHERE BUFKIT FORECASTS OF CAPES OF 500-1000 J/KG...AND
AROUND 40 KT BULK SHEAR WILL BE REALIZED IF LIFT IS STRONG ENOUGH.
BUFKIT HAD NO CIN OVER KBHK LATE IN THE DAY. SURFACE TROUGH WAS
OVER CENTRAL ZONES THIS MORNING PER SURFACE OBSERVATIONS. RAP AND
WRF MOVED TROUGH E WITH TIME WITH A SURFACE LOW OVER WY. WEAK COLD
FRONT WILL CATCH UP TO THE TROUGH THIS AFTERNOON. THESE FACTORS
WILL COMBINE WITH INCREASING VORTICITY TO BRING A SLIGHT CHANCE OF
THUNDERSTORMS TO MAINLY CARTER AND FALLON COUNTIES. STORMS WILL BE
FAIRLY FAST-MOVING DUE MODERATELY FAST FLOW ALOFT. CAPES AND BULK
SHEAR SUPPORTED POSSIBLE SEVERE STORMS OVER THE SE ZONES. MIXING
TO ABOVE 700 MB SUPPORTED TEMPERATURES NEAR RECORD VALUES IN SOME
LOCATIONS. ONLY COMPLICATING FACTOR FOR THE TEMPERATURES REACHING
THESE VALUES WILL BE HIGH CLOUD COVER COMING IN FROM THE SW.
ARTHUR
&&
.SHORT TERM...VALID FOR TDY AND FRI...
TODAY WE ARE EXPECTING SOME OF THE HOTTEST TEMPERATURES OF THE
SEASON SO FAR. AS AN UPPER LEVEL RIDGE AXIS SHIFTS EAST OF US THE
MID LEVEL THERMAL AXIS WILL INCREASE OVER OUR REGION IN AN
INCREASING SW FLOW. BUFKIT OVERVIEWS SUGGEST MIXING WELL ABOVE
700MB WILL TAKE PLACE AND BRING SOME VERY WARM AIR DOWN INTO THE
BOUNDARY LAYER. NUMERICAL GUIDANCE TRENDS CONFIRM THIS AND I HAVE
THEREFORE BOOSTED TEMPERATURES FROM A FEW TO SEVERAL DEGREES IN
MANY AREAS...ESPECIALLY THE AREAS BETWEEN BILLINGS AND MILES CITY
WHERE THE MERCURY WILL BENEFIT MOST FROM THE TIMING OF A WEAK
FRONT MOVING THROUGH THE AREA THIS AFTERNOON. A FEW LOCATIONS SUCH
AS MILES CITY MAY THREATEN THEIR RECORD HIGHS.
AS FOR PRECIPITATION TODAY...THE AFOREMENTIONED FRONT WILL RUN
INTO SOME HIGH CAPE ALONG THE EASTERN BORDER COUNTIES WHERE THE
VERTICAL WIND PROFILES SUGGEST SOME DEEP LAYERED SHEAR. I SUSPECT
WE COULD SEE AN ISOLATED SEVERE STORM DEVELOP HERE IN THE MID TO
LATE AFTERNOON HOURS...SO WILL ADD SEVERE WORDING IN THE FAR
EASTERN ZONES. MUCH OF THIS ACTIVITY WILL PROBABLY BE IN THE
DAKOTAS BY EVENING. ALSO...OUT WEST THERE IS AN OBVIOUS INFLUX OF
MOISTURE FROM THE SW EVIDENT ON WATER VAPOR LOOPS. PROGGS ALSO
INDICATE A DECENT SHORT WAVE COMING OUT OF THE MOUNTAINS. SO
ISOLATED STORMS IN OUR WEST TO NORTHWEST ZONES LOOK GOOD FOR
LATER TODAY...THOUGH THE ENVIRONMENT THERE IS DRIER IN THE LOW
LEVELS AND WILL NOT SUPPORT MUCH CHANCE OF SEVERE STORMS.
LOOK FOR COOLER TEMPERATURES ON FRIDAY WITH A SLIGHT CHANCE OF
THUNDERSTORMS. BT
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
EXTENDED FORECAST COULD BE CONSIDERED TYPICAL FOR MID JULY...
GENERALLY HOT WITH AT LEAST A SLIGHT CHANCE OF TSTMS EACH DAY.
PATTERN OVER THE NORTHERN ROCKIES WILL BE INFLUENCED BY STRONG
RIDGING OVER THE INTERMOUNTAIN WEST...WITHIN WHICH THERE WILL BE
MONSOONAL SURGES...AND PIECES OF SHORTWAVE ENERGY FROM PAC COAST
TROF AND WESTERN CANADA. HIGHER THETA-E AIR SUPPORTIVE OF
STRONGER TSTM ACTIVITY WILL GENERALLY RESIDE IN OUR EAST NEAR THE
DAKOTAS BORDER...AND HAVE KEPT HIGHEST POPS IN THIS AREA...BUT
COULD SEE AN OCCASIONAL WESTWARD PUSH OF THIS MOISTURE ESPECIALLY
MON-WED OF NEXT WEEK WITH EAST WIND REGIME IN PLACE. EXPECT
TEMPERATURES TO BE NEAR OR SLIGHTLY ABOVE NORMAL EACH DAY...WITH
THE EXPECTATION THAT PACIFIC ENERGY WILL KEEP THE RIDGE SUPPRESSED
ENOUGH TO NOT ALLOW FOR ANY SIGNIFICANT SURGES OF HEAT...WHICH WE
ARE CERTAINLY PRONE TO DO AS WE ENTER OUR HOTTEST TIME OF YEAR.
JKL
&&
.AVIATION...
ISOLATED THUNDERSTORMS WILL DEVELOP OVER THE AREA FROM KBIL W
THIS AFTERNOON AND EVENING. THUNDERSTORMS SHOULD BE MAINLY HIGH-
BASED WITH GUSTY WINDS TO 40 KT. FURTHER E...FROM KMLS E AND
SE...ISOLATED THUNDERSTORMS WILL ALSO DEVELOP THIS AFTERNOON AND
MOVE E THROUGH THIS EVENING. MVFR CONDITIONS...LARGE HAIL AND
WIND GUSTS TO 60 KT WILL ACCOMPANY THESE STORMS. VFR CONDITIONS
WILL PREVAIL LATE TONIGHT AND FRI MORNING. LOCALIZED MOUNTAIN
OBSCURATION WILL OCCUR THROUGH THE PERIOD DUE TO ISOLATED
MOUNTAIN SHOWERS AND THUNDERSTORMS. ARTHUR
&&
.PRELIMINARY POINT TEMP/POPS...
TDY FRI SAT SUN MON TUE WED
-------------------------------------------------------
BIL 098 064/090 062/090 061/087 062/093 063/093 065/096
2/T 21/B 12/T 22/T 22/T 22/T 22/T
LVM 093 057/087 053/090 051/088 051/090 052/092 057/095
2/T 22/T 22/T 22/T 22/T 22/T 22/T
HDN 101 064/090 062/092 059/089 061/094 063/095 065/097
0/G 11/B 12/T 22/T 22/T 22/T 22/T
MLS 103 067/091 064/091 063/088 064/094 064/094 067/096
2/T 11/B 22/T 22/T 23/T 32/T 22/T
4BQ 101 063/090 060/091 061/087 061/092 061/093 062/095
2/T 11/B 22/T 22/T 23/T 32/T 22/T
BHK 096 063/087 061/088 062/084 061/088 062/091 065/092
2/T 21/B 23/T 33/T 33/T 33/T 22/T
SHR 099 060/088 057/091 056/087 056/091 056/092 060/093
0/B 11/B 22/T 22/T 23/T 32/T 22/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1041 AM CDT THU JUL 11 2013
.UPDATE...
ISSUED AT 1006 AM CDT THU JUL 11 2013
ENHANCED CLOUDS AND ISOLATED SHOWERS ARE MOVING INTO THE FAR
WESTERN COUNTIES AND OPTED FOR SLIGHT CHANCE POPS THROUGH THE
AFTERNOON. THE MAIN ACTIVITY...WITH SOME SEVERE STORMS...STILL
EXPECTED TO HOLD OFF UNTIL AFTER 00Z.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 405 AM CDT THU JUL 11 2013
CURRENTLY...SURFACE HIGH PRESSURE WAS OVER SOUTHERN MINNESOTA AND
IOWA WITH LOW PRESSURE IN THE LEE OF THE ROCKIES. SOUTH/SOUTHEAST
SURFACE WINDS ACROSS THE REGION WAS ALLOWING INCREASING LOW LEVEL
MOISTURE WITH DEWPOINTS IN THE UPPER 50S TO MID 60S. MESOANALYSIS
INDICATES A LOW LEVEL JET HAD DEVELOPED FROM THE SOUTHERN PLAINS
INTO THE WESTERN DAKOTAS. THE LEADING EDGE OF THE JET...WITH
INCREASING SOUTHEAST WINDS AND DEWPOINTS WAS PROVIDING ENOUGH LIFT
FOR MID-LEVEL CLOUD DEVELOPMENT SEEN ON SATELLITE PICS EXTENDING
FROM NEAR DICKINSON TO MOBRIDGE TO SOUTH CENTRAL SOUTH DAKOTA.
REGIONAL RADARS PICKING UP ON SMALL CELLS TRYING TO DEVELOP IN THIS
LINE IN SOUTH DAKOTA - IN THE PAST HOUR OR TWO THE SMALL CELLS BEGIN
TO DEVELOP AND THEN DISSIPATE. AFTER 2 AM A CELL NEAR PIERRE WAS
BECOMING MORE ROBUST WITH DBZ VALUES ABOVE 50. THE HRRR 1KM
REFLECTIVITY DEPICTED THIS CONVECTION - AND KEEPS MOST OF IT MAINLY
IN SOUTH DAKOTA THIS MORNING...BUT INDICATES THE POTENTIAL IN SOUTH
CENTRAL NORTH DAKOTA TOWARDS DAYBREAK. HIGH EFFECTIVE BULK SHEAR AND
1000-2000 J/KG CAPE IN SOUTHWESTERN NORTH DAKOTA...MID-LEVEL LAPSE
RATES ARE HIGHER IN SOUTH CENTRAL AND WESTERN SOUTH DAKOTA...BUT
POTENTIAL FOR SOME CELLS THIS MORNING - WILL ADD A MENTION OF SLIGHT
CHC OF THUNDERSTORMS THIS MORNING.
AS TIME GOES ON TODAY...THE MID LEVEL CAP IS FORECAST TO
STRENGTHEN...WITH H700 TEMPERATURES AS PER THE NAM RISING TO +10C IN
THE DEVILS LAKE/JAMES RIVER BASINS BY NOON...AND TO +14C IN THE FAR
SOUTHWEST. THIS CAP SHOULD ACT TO KEEP SKIES CLEAR AND FREE OF
CONVECTION DURING THE DAYTIME. MEANWHILE DEWPOINT TEMPERATURES IN
THE 60S TO NEAR 70 WILL MAKE FOR A VERY WARM/HOT AND HUMID DAY
ACROSS THE FORECAST AREA TODAY.
THIS EVENING...THE LEADING EDGE OF UPPER LEVEL SHORTWAVE ENERGY
REACHES THE WESTERN ND BORDER IN THE SOUTHWEST FLOW ALOFT. AT THE
SURFACE...IN RESPONSE THE LEE-SIDE LOW PRESSURE TROUGH MOVES/DEVELOPS
EASTWARD AND REACHES THE WESTERN DAKOTAS EARLY EVENING. THE QUESTION
IS WHETHER THE UPPER LEVEL SHORTWAVE ENERGY WILL DISTURB THE
MID-LEVEL THERMAL CAP TO ALLOW CONVECTION BY LATE AFTERNOON/EARLY
EVENING...OR WHETHER CONVECTION WILL BEGIN JUST BEFORE/AROUND SUNSET
WHEN THE MID-LEVEL CAP WOULD WEAKEN A BIT. FORECAST CAPE VALUES OF
1500-3000 J/KG AND 0-6KM BULK SHEAR ABOVE 45KTS THIS EVENING AND
LATE NIGHT WILL PROVIDE PLENTY OF INSTABILITY FOR THE MENTION OF
SEVERE THUNDERSTORM POSSIBILITIES. EASTERN MT/WY AND THE WESTERN
DAKOTAS ARE IN THE SPC DAY1 SLIGHT RISK FOR SEVERE THUNDERSTORMS.
KEPT THE CHANCE OF PRECIPITATION IN THE EVENING MAINLY IN THE WEST
AND NORTH CENTRAL...AND INCREASED CHANCES IN CENTRAL NORTH DAKOTA
AFTER MIDNIGHT TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 405 AM CDT THU JUL 11 2013
WE REMAIN IN A TYPICAL MID-SUMMER WEATHER PATTERN WITH THE UPPER
LEVEL JET STREAM NEAR THE NORTHERN PLAINS REGION THROUGH MUCH OF
THE LONG TERM FORECAST PERIOD...RESULTING IN PERIODS OF SHOWERS
AND THUNDERSTORMS FOR THE NEXT SEVERAL DAYS.
FRIDAY INTO FRIDAY NIGHT...SFC TROUGH BY 12Z FRIDAY WILL BE MOVING
EAST ACROSS CENTRAL NORTH DAKOTA. BY FRIDAY AFTERNOON...MODELS
POSITION THE SFC TROUGH FROM CENTRAL SOUTH DAKOTA NORTH-NORTHEAST
INTO NORTHEASTERN NORTH DAKOTA. THIS WILL PUT THE BEST CHANCES
FOR ACCUMULATING PRECIPITATION/STRONGER THUNDERSTORMS MAINLY EAST
OF HIGHWAY 83 WITH THE BETTER COVERAGE/CHANCES OVER THE JAMES
RIVER VALLEY INTO THE RED RIVER VALLEY AREA WITH MINIMAL
INSTABILITY OVER THE WESTERN HALF OF THE STATE THANKS TO DRY AIR
ADVECTION. MAINLY DRY OVER WEST AND CENTRAL NORTH DAKOTA FRIDAY
EVENING WITH WEAK SFC HIGH PRESSURE IN PLACE ACROSS THE CENTRAL
PART OF THE STATE. WE START TO SEE INCREASING CHANCES FOR
THUNDERSTORMS LATE FRIDAY NIGHT WEST WHERE ANOTHER AREA OF SURFACE
LOW PRESSURE ARRIVES FROM EASTERN MONTANA.
THIS SURFACE LOW...ALONG WITH MID LEVEL S/WV`S LIFTING NORTHEAST
THROUGH THE STATE...WILL BE THE FOCUS FOR DECENT THUNDERSTORM
CHANCES SATURDAY/SATURDAY NIGHT. STRONG TO SEVERE STORMS WILL BE
POSSIBLE GIVEN 1-2K J/KG OF MUCAPE AND 0-6KM SHEAR 35KTS OR
GREATER. THE DAY 3 SPC OUTLOOK HAS INCLUDED THE ENTIRE STATE OF ND
IN THE SLIGHT RISK FOR SEVERE WEATHER.
A QUIET PERIOD IS IN THE OFFING LATER SUNDAY THROUGH SUNDAY NIGHT
WITH HIGH PRESSURE BUILDING SOUTH ACROSS THE REGION. OPTED TO
MAINTAIN SLIGHT CHANCE POPS FOR NOW SUNDAY NIGHT IN CASE THE 00Z
GFS PROVES MORE CORRECT WHICH KEEPS HIGH PRESSURE MORE OVER
SOUTHERN CANADA. THE LAST FEW RUNS OF THE ECMWF BUILD THE SFC HIGH
OVER NORTH DAKOTA AND WOULD SUPPORT DRY WEATHER.
THE PARADE OF MID LEVEL WAVES CONTINUES...AND WILL MAINTAIN SOME
MENTION FOR THUNDERSTORMS THROUGH THE MIDDLE OF NEXT WEEK.
TEMPERATURES WILL AVERAGE NORMAL THROUGH THE PERIOD...WITH HIGHS
IN THE 80S TO LOW/MID 90S...AND LOWS MID 50S TO THE UPPER 60S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1006 AM CDT THU JUL 11 2013
THUNDERSTORM CHANCES WILL INCREASE AFTER 00Z THIS EVENING FROM
WEST TO EAST. CURRENTLY HAVE VCTS MENTIONS...AND WILL LIKELY
REFINE TIMING AT 18Z ISSUANCE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE/AVIATION...RP KINNEY
SHORT TERM...JV
LONG TERM...NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
657 AM CDT THU JUL 11 2013
.UPDATE...
ISSUED AT 656 AM CDT THU JUL 11 2013
INHERITED FORECAST LOOKS GOOD. NO CHANGES BESIDES UPDATING THE
CURRENT OBS AND ADJUSTING HOURLY TRENDS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 405 AM CDT THU JUL 11 2013
CURRENTLY...SURFACE HIGH PRESSURE WAS OVER SOUTHERN MINNESOTA AND
IOWA WITH LOW PRESSURE IN THE LEE OF THE ROCKIES. SOUTH/SOUTHEAST
SURFACE WINDS ACROSS THE REGION WAS ALLOWING INCREASING LOW LEVEL
MOISTURE WITH DEWPOINTS IN THE UPPER 50S TO MID 60S. MESOANALYSIS
INDICATES A LOW LEVEL JET HAD DEVELOPED FROM THE SOUTHERN PLAINS
INTO THE WESTERN DAKOTAS. THE LEADING EDGE OF THE JET...WITH
INCREASING SOUTHEAST WINDS AND DEWPOINTS WAS PROVIDING ENOUGH LIFT
FOR MID-LEVEL CLOUD DEVELOPMENT SEEN ON SATELLITE PICS EXTENDING
FROM NEAR DICKINSON TO MOBRIDGE TO SOUTH CENTRAL SOUTH DAKOTA.
REGIONAL RADARS PICKING UP ON SMALL CELLS TRYING TO DEVELOP IN THIS
LINE IN SOUTH DAKOTA - IN THE PAST HOUR OR TWO THE SMALL CELLS BEGIN
TO DEVELOP AND THEN DISSIPATE. AFTER 2 AM A CELL NEAR PIERRE WAS
BECOMING MORE ROBUST WITH DBZ VALUES ABOVE 50. THE HRRR 1KM
REFLECTIVITY DEPICTED THIS CONVECTION - AND KEEPS MOST OF IT MAINLY
IN SOUTH DAKOTA THIS MORNING...BUT INDICATES THE POTENTIAL IN SOUTH
CENTRAL NORTH DAKOTA TOWARDS DAYBREAK. HIGH EFFECTIVE BULK SHEAR AND
1000-2000 J/KG CAPE IN SOUTHWESTERN NORTH DAKOTA...MID-LEVEL LAPSE
RATES ARE HIGHER IN SOUTH CENTRAL AND WESTERN SOUTH DAKOTA...BUT
POTENTIAL FOR SOME CELLS THIS MORNING - WILL ADD A MENTION OF SLIGHT
CHC OF THUNDERSTORMS THIS MORNING.
AS TIME GOES ON TODAY...THE MID LEVEL CAP IS FORECAST TO
STRENGTHEN...WITH H700 TEMPERATURES AS PER THE NAM RISING TO +10C IN
THE DEVILS LAKE/JAMES RIVER BASINS BY NOON...AND TO +14C IN THE FAR
SOUTHWEST. THIS CAP SHOULD ACT TO KEEP SKIES CLEAR AND FREE OF
CONVECTION DURING THE DAYTIME. MEANWHILE DEWPOINT TEMPERATURES IN
THE 60S TO NEAR 70 WILL MAKE FOR A VERY WARM/HOT AND HUMID DAY
ACROSS THE FORECAST AREA TODAY.
THIS EVENING...THE LEADING EDGE OF UPPER LEVEL SHORTWAVE ENERGY
REACHES THE WESTERN ND BORDER IN THE SOUTHWEST FLOW ALOFT. AT THE
SURFACE...IN RESPONSE THE LEE-SIDE LOW PRESSURE TROUGH MOVES/DEVELOPS
EASTWARD AND REACHES THE WESTERN DAKOTAS EARLY EVENING. THE QUESTION
IS WHETHER THE UPPER LEVEL SHORTWAVE ENERGY WILL DISTURB THE
MID-LEVEL THERMAL CAP TO ALLOW CONVECTION BY LATE AFTERNOON/EARLY
EVENING...OR WHETHER CONVECTION WILL BEGIN JUST BEFORE/AROUND SUNSET
WHEN THE MID-LEVEL CAP WOULD WEAKEN A BIT. FORECAST CAPE VALUES OF
1500-3000 J/KG AND 0-6KM BULK SHEAR ABOVE 45KTS THIS EVENING AND
LATE NIGHT WILL PROVIDE PLENTY OF INSTABILITY FOR THE MENTION OF
SEVERE THUNDERSTORM POSSIBILITIES. EASTERN MT/WY AND THE WESTERN
DAKOTAS ARE IN THE SPC DAY1 SLIGHT RISK FOR SEVERE THUNDERSTORMS.
KEPT THE CHANCE OF PRECIPITATION IN THE EVENING MAINLY IN THE WEST
AND NORTH CENTRAL...AND INCREASED CHANCES IN CENTRAL NORTH DAKOTA
AFTER MIDNIGHT TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 405 AM CDT THU JUL 11 2013
WE REMAIN IN A TYPICAL MID-SUMMER WEATHER PATTERN WITH THE UPPER
LEVEL JET STREAM NEAR THE NORTHERN PLAINS REGION THROUGH MUCH OF
THE LONG TERM FORECAST PERIOD...RESULTING IN PERIODS OF SHOWERS
AND THUNDERSTORMS FOR THE NEXT SEVERAL DAYS.
FRIDAY INTO FRIDAY NIGHT...SFC TROUGH BY 12Z FRIDAY WILL BE MOVING
EAST ACROSS CENTRAL NORTH DAKOTA. BY FRIDAY AFTERNOON...MODELS
POSITION THE SFC TROUGH FROM CENTRAL SOUTH DAKOTA NORTH-NORTHEAST
INTO NORTHEASTERN NORTH DAKOTA. THIS WILL PUT THE BEST CHANCES
FOR ACCUMULATING PRECIPITATION/STRONGER THUNDERSTORMS MAINLY EAST
OF HIGHWAY 83 WITH THE BETTER COVERAGE/CHANCES OVER THE JAMES
RIVER VALLEY INTO THE RED RIVER VALLEY AREA WITH MINIMAL
INSTABILITY OVER THE WESTERN HALF OF THE STATE THANKS TO DRY AIR
ADVECTION. MAINLY DRY OVER WEST AND CENTRAL NORTH DAKOTA FRIDAY
EVENING WITH WEAK SFC HIGH PRESSURE IN PLACE ACROSS THE CENTRAL
PART OF THE STATE. WE START TO SEE INCREASING CHANCES FOR
THUNDERSTORMS LATE FRIDAY NIGHT WEST WHERE ANOTHER AREA OF SURFACE
LOW PRESSURE ARRIVES FROM EASTERN MONTANA.
THIS SURFACE LOW...ALONG WITH MID LEVEL S/WV`S LIFTING NORTHEAST
THROUGH THE STATE...WILL BE THE FOCUS FOR DECENT THUNDERSTORM
CHANCES SATURDAY/SATURDAY NIGHT. STRONG TO SEVERE STORMS WILL BE
POSSIBLE GIVEN 1-2K J/KG OF MUCAPE AND 0-6KM SHEAR 35KTS OR
GREATER. THE DAY 3 SPC OUTLOOK HAS INCLUDED THE ENTIRE STATE OF ND
IN THE SLIGHT RISK FOR SEVERE WEATHER.
A QUIET PERIOD IS IN THE OFFING LATER SUNDAY THROUGH SUNDAY NIGHT
WITH HIGH PRESSURE BUILDING SOUTH ACROSS THE REGION. OPTED TO
MAINTAIN SLIGHT CHANCE POPS FOR NOW SUNDAY NIGHT IN CASE THE 00Z
GFS PROVES MORE CORRECT WHICH KEEPS HIGH PRESSURE MORE OVER
SOUTHERN CANADA. THE LAST FEW RUNS OF THE ECMWF BUILD THE SFC HIGH
OVER NORTH DAKOTA AND WOULD SUPPORT DRY WEATHER.
THE PARADE OF MID LEVEL WAVES CONTINUES...AND WILL MAINTAIN SOME
MENTION FOR THUNDERSTORMS THROUGH THE MIDDLE OF NEXT WEEK.
TEMPERATURES WILL AVERAGE NORMAL THROUGH THE PERIOD...WITH HIGHS
IN THE 80S TO LOW/MID 90S...AND LOWS MID 50S TO THE UPPER 60S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 656 AM CDT THU JUL 11 2013
MAINLY CLEAR SKIES FOR THIS TAF ISSUANCE. THE ONLY EXCEPTION IS A
LINE OF SHOWERS AND ISOLATED THUNDERSTORMS THAT HAD FORMED ALONG THE
EASTERN EDGE OF A LOW LEVEL JET AND WERE MOVING
EASTWARD/NORTHEASTWARD. AT THIS TIME NONE OF THE CONVECTIVE CELLS
APPEARS TO THREATEN ANY OF THE TAF SITES...THOUGH ONE CELL DEVELOPED
OVER KBIS BUT WAS MOVING AWAY FROM KBIS.
SOUTHEAST WINDS TO INCREASE AFT 15Z AND ESPECIALLY AFT 18Z. THE
CHANCE OF THUNDERSTORMS IS MAINLY AFT 00Z AND HAVE VCTS MENTIONED AT
KISN/KDIK/KMOT AFT 00Z...AND AT KBIS AFT 06Z AND AFT 09Z AT KJMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...JV
LONG TERM...NH
AVIATION...JV
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
1030 AM EDT THU JUL 11 2013
.DISCUSSION...
SURFACE ANALYSIS SHOWS A COLD FRONT LOCATED ALONG THE OHIO RIVER.
DEWPOINTS AHEAD OF THE FRONT REMAIN IN THE UPPER 60S TO LOWER 70S.
ALOFT...THE 12Z OHX SOUNDING SHOWS VERY DRY AIR ABOVE 650 MB. THE
RUC IS SHOWING SOME CONVECTION DEVELOPING OVER CNTL KY AND MIDDLE
TN THIS AFTERNOON IN A WEAK CONVERGENCE ZONE AHEAD OF THE FRONT. RUC
FORECAST SOUNDINGS SHOW VERY LITTLE CIN THIS AFTERNOON...WITH CAPE
VALUES IN THE 1500-2000 J/KG RANGE. THE DRY AIR ALOFT RESULTS IN
HIGH DCAPE VALUES AND SURFACE-TO-MIDLEVEL THETA-E DIFFERENCES
AROUND 30 DEGREES. SO WHILE THE DRY AIR ALOFT SHOULD REDUCE
COVERAGE OF STORMS THROUGH ENTRAINMENT COMPARED TO YESTERDAY...ANY
STORMS THAT DEVELOP COULD PRODUCE DAMAGING WIND GUSTS.
THE RUC SHOWS GREATEST INSTABILITY AND LOW LEVEL CONVERGENCE ACROSS
SOUTHERN AREAS THIS AFTERNOON...SO WILL ADJUST POPS UPWARD IN THAT
AREA AND DOWNWARD NORTH SLIGHTLY. EXTENSIVE CLOUD COVER THIS
MORNING IS HOLDING TEMPS BACK A BIT...SO WILL LOWER HIGH TEMPS
SLIGHTLY.
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
936 AM CDT THU JUL 11 2013
.UPDATE...
QUIET WEATHER TODAY AS SFC HIGH PRESSURE CENTERS OVER THE
FORECAST AREA. FEW CHANGES MADE...MOSTLY KEEPING TEMP/WIND/DEW
POINT TRENDS ON TRACK. ONLY CONCERN IS SKY COVER TODAY. AMDAR
SOUNDING AT AROUND 1130Z SHOWS VERY DRY AIR ALOFT THAT ISNT QUITE
BEING CAPTURED BY NEARBY RAP PROXIMITY SOUNDINGS. DOES SHOW
LINGERING MOISTURE AT LOW-LEVELS THOUGH. AS SUCH...GIVEN THIS AND
FCST SOUNDINGS...FEW-SCT DIURNAL CU STILL EXPECTED TO DEVELOP
LATER THIS MORNING.
OTHERWISE...TODAYS HIGH TEMPERATURES APPEAR FINE. SHOULD SEE MORE
THAN SUFFICIENT INSOLATION/SUNSHINE AND MIXING TODAY.
&&
.AVIATION/18Z TAFS/...VFR CONDITIONS TO PERSIST THROUGH THE TAF
PERIOD AT ALL TAF SITES. WINDS WILL BE LIGHT WITH AN ONSHORE
FLOW DEVELOPING LATE THIS MORNING. ALSO...SCT CU EXPECTED TO
DEVELOP LATE THIS MORNING...WILL TRANSITION TO FEW/CLR IN THE
AFTERNOON NEAR THE LAKE SHORE. PATCHY LIGHT FOG POSSIBLE LATER
TONIGHT.
&&
.PREV DISCUSSION... /ISSUED 331 AM CDT THU JUL 11 2013/
SHORT TERM...
TODAY AND TONIGHT - CONFIDENCE...HIGH.
BRIEF PERIOD OF MID-CLOUDS EXPECTED OVER PORTIONS OF ERN CWA EARLY
THIS MRNG ASSOCIATED WITH VIGOROUS MID-LEVEL SHORT WAVE CURRENTLY
OVER NORTH CENTRAL WI. SPRINKLES POSSIBLE IN KFDL/KSBM AREA PRIOR
TO 12Z. SHORT WAVE MOVES RAPIDLY OFF TO THE EAST EARLY THIS MRNG
ALONG WITH MID-CLOUDS SO STILL EXPECT M/S CONDITIONS FOR MOST OF THE
DAYTIME. ENOUGH LINGERING LOW LEVEL MOISTURE TO RESULT IN SCT CU
REDEVELOPING THIS MRNG. MAY ALSO BE PERIOD OF BKN CU AWAY FROM LAKE
MICHIGAN LATER THIS MRNG BUT WL CONTINUE M/S WORDING FOR NOW.
QUIET AND COMFORTABLE CONDITIONS CONTINUE TONIGHT WITH LARGE SCALE
BLOCKING RIDGE REMAINING OVER THE CENTRAL AND PARTS OF THE WESTERN
GTLAKES. WEAK RETURN FLOW DOES INCREASE OVER WESTERN CWA DURING THE
NIGHT...HOWEVER SHOULD NOT HAVE MUCH BEARING ON OVERNIGHT TEMPS DUE
TO STRONG INVERSION. LIGHTER BOUNDARY LAYER WINDS IN EASTERN CWA MAY
RESULT IN PATCHY LIGHT FOG IN SUSCEPTIBLE AREAS LATE TONIGHT.
FRIDAY THROUGH SATURDAY...FORECAST CONFIDENCE HIGH.
SURFACE HIGH PRESSURE WILL CONTINUE TO DRIFT EAST THROUGH THE GREAT
LAKES REGION. SUNNY SKIES WILL CONTINUE ACROSS SOUTHERN WI WITH
HIGHS IN THE LOWER 80S. SOUTHEAST WINDS WILL KEEP TEMPS NEAR THE
LAKE A FEW DEGREES COOLER.
THUNDERSTORM CHANCES WITH SHORTWAVES WILL BE WELL TO OUR NORTH AND
WEST...BUT SOUTHERN WI COULD SEE SPILL OVER OF HIGHER CLOUDS AT
TIMES...ESPECIALLY SATURDAY.
LONG TERM...
SUNDAY THROUGH TUESDAY...FORECAST CONFIDENCE MEDIUM.
THE CURRENT UPPER TROUGH DROPPING THROUGH THE GREAT LAKES REGION
THIS MORNING IS FORECAST TO CLOSE OFF OVER PENNSYLVANIA ON FRIDAY
AND THEN RETROGRADE BACK THROUGH THE MIDWEST SUNDAY THROUGH TUESDAY
AS A STRONG ATLANTIC HIGH TAKES CONTROL. ALL MODELS ARE SHOWING THIS
CLOSED UPPER LOW FEATURE. WITH ANY UPPER LOW...THERE ARE TIMING
ISSUES REGARDING ITS MOVEMENT AND ASSOCIATED PRECIPITATION.
THE LATEST 00Z ECMWF CAME IN LINE WITH THE 00Z GFS WHICH RETROGRADES
THE UPPER LOW QUICKLY INTO THE CENTRAL PLAINS BY SUNDAY AND HAS
LITTLE EFFECT ON SOUTHERN WISCONSIN WEATHER. THIS IS DIFFERENT THAN
THE 12Z ECMWF RUN WHICH HAD A SLOWER MOVEMENT AND WETTER SOLUTION
FOR SRN WI. THE 00Z CANADIAN HAS THIS SLOWER AND WETTER SOLUTION.
THE EXTENDED FORECAST USED A CONSENSUS OF MODELS THAT INCLUDED THE
12Z ECMWF. THEREFORE...THERE ARE LOTS OF SLIGHT CHANCE POPS
SPLATTERED ACROSS SOUTHERN WI FROM SUNDAY THROUGH TUESDAY. GIVEN THE
NEW 00Z ECMWF RUN...THOSE POPS WILL PROBABLY BE ABLE TO BE REDUCED
IN LATER FORECASTS. MODEL SOUNDINGS LOOK PRETTY STABLE WITH THE
UPPER LOW MOVING ACROSS THE MIDWEST...THUS PRECIP SHOULD JUST BE
SHOWERS WITH THUNDERSTORMS LESS LIKELY.
WE WERE PREVIOUSLY TALKING ABOUT A BIG WARM-UP INTO THE 90S NEXT
WEEK...BUT THAT IS BECOMING LESS LIKELY NOW DUE TO THAT CLOSED
UPPER LOW MOVING THROUGH THE REGION.
WEDNESDAY AND BEYOND...FORECAST CONFIDENCE MEDIUM.
AS THE CLOSED UPPER LOW RETROGRADES INTO THE CENTRAL PLAINS AND HIGH
PRESSURE BECOMES CENTERED OVER THE EASTERN SEABOARD...SOUTHERN WI
WILL BE THE SUBJECT OF RETURN FLOW WITH MOISTURE FLOWING UP FROM THE
GULF. THIS WILL OCCUR AT THE SAME TIME THAT THE MAIN 500MB FLOW
COULD DIP DOWN INTO CENTRAL OR SOUTHERN WI TO PRODUCE THUNDERSTORMS.
STAY TUNED.
AVIATION/12Z TAFS/...BRIEF PERIOD OF LIGHT FOG MAY AFFECT TAF SITES
EARLY THIS MORNING. OTRW EXPECTING SCT CU TO REDEVELOP THIS
MRNG...POSSIBLY TURNING BRIEFLY VFR BKN AWAY FROM LAKE SHORE LATER
THIS MRNG AND EARLY AFTN. MORE PATCHY LIGHT FOG EXPECTED LATER
TONIGHT IN LIGHTER BOUNDARY LAYER REGIME.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...ET
TODAY/TONIGHT AND AVIATION/MARINE...MBK
FRIDAY THROUGH WEDNESDAY...MRC
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
230 PM MST THU JUL 11 2013
...UPDATED TO AVIATION AND FIRE WEATHER DISCUSSION...
&&
.SYNOPSIS...
FAVORABLE SOUTHERLY FLOW WILL CONTINUE TO IMPORT DEEPER MONSOON
MOISTURE INTO THE REGION OVER THE NEXT COUPLE DAYS. THIS WILL LEAD
TO MORE NUMEROUS SHOWERS AND THUNDERSTORMS ACROSS THE ENTIRE AREA
LASTING THROUGH FRIDAY. THE INCREASED MOISTURE WILL ALSO RESULT IN
COOLER DAYTIME TEMPERATURES FOR THE REST OF THE WORK WEEK. WARMER
TEMPERATURES AND A GENERAL DECREASE IN THUNDERSTORM ACTIVITY CAN BE
EXPECTED OVER THE WEEKEND AND INTO EARLY NEXT WEEK.
&&
.DISCUSSION.../ISSUED 216 PM MST THU JUL 11/
SMALL DAY TO DAY CHANGES IN THE ATMOSPHERIC PROFILE CAN MAKE A WORLD
OF DIFFERENCE IN THE CONVECTIVE POTENTIAL. THIS IS CERTAINLY THE
CASE FOR THE SOUTHWEST MONSOON. ALTHOUGH IT WOULD HAVE APPEARED
YESTERDAY THAT ALL THE KEY INGREDIENTS WERE IN PLACE FOR DEVELOPMENT
OF MORE WIDESPREAD CONVECTION ACROSS THE FORECAST AREA...ONLY A FEW
STORMS MANAGED TO WORK THEIR WAY INTO EAST CENTRAL AZ DESERTS. LA
PAZ AND YUMA COUNTIES AND POINTS WEST DID SEE MORE WIDESPREAD
COVERAGE OF SHOWERS AND STORMS...WITH ADDITIONAL DYNAMICS PROVIDED
BY A LOW AND INVERTED TROUGH SWEEPING ALONG THE INTERNATIONAL
BORDER IN THE VICINITY OF THE INTERNATIONAL BORDER. THE LATEST 19Z
K1Y8 (YUMA) SOUNDING SHOWS A PROFILE RIPE FOR STORMS...WITH A STRONG
SOUTHERLY FLOW...PWAT OF 1.86 INCH...AND CAPE OF OVER 1600 J/JG.
THERE IS SOME CONVECTIVE INHIBITION...BUT THIS SHOULDN/T KEEP MORE
SHOWERS AND STORMS FROM DEVELOPING AGAIN THIS AFTERNOON AND EVENING.
A FEW SHOWERS AND STORMS ARE STILL CONTINUING IN LA PAZ AND
RIVERSIDE COUNTIES...AND THE HRRR WHICH PERFORMED THE BEST OF
MESOSCALE MODELS WITH THE EARLY MORNING CONVECTION SHOWS CONVECTION
CONTINUING IN THIS REGION FOR THE NEXT SEVERAL HOURS. MEANWHILE IN
EAST CENTRAL AZ STORMS BEGAN DEVELOPING EARLY OVER PIMA COUNTY AND
ATTEMPTED MOVED NORTH INTO PINAL COUNTY. EARLY STORMS QUICKLY
DISSIPATED BEFORE THEY COULD WORK THEIR WAY INTO THE PHOENIX
FORECAST AREA. CLOUD COVER REMAINED OVER EAST CENTRAL ARIZONA FOR
MUCH OF THE DAY. THIS KEPT TEMPERATURES SEVERAL DEGREES COOLER THAN
ON WEDNESDAY FOR MOST OF THE DAY. IN THE LAST COUPLE OF HOURS CLOUD
COVER HAS BEGUN SCATTERING OUT THOUGH...TEMPERATURES HAVE BEGUN
CLIMBING AND THE AIRMASS HAS BECOME MORE UNSTABLE. THIS WILL LIKELY
ALLOW A FEW STORMS TO WORK THEIR WAY FURTHER INTO THE DESERT
SOUTHWEST. WITH PWAT NEAR TWO INCHES...STORMS THAT DO DEVELOP HAVE
THE POTENTIAL TO PRODUCE LOCALIZED HEAVY RAINFALL. THERE REMAINS A
THREAT OF BLOWING DUST ALONG THE I-10 AND I-8 CORRIDORS IN EAST
CENTRAL ARIZONA AS OUTFLOW BOUNDARIES WORKING THEIR WAY NORTH AHEAD
OF STORMS PUSHING NORTH OUT OF PIMA COUNTY.
DO NOT HAVE GOOD CONFIDENCE IN FRIDAYS FORECAST. MOISTURE AND
INSTABILITY WILL REMAIN SUFFICIENT...THOUGH AS NOTED ABOVE LITTLE
CHANGES IN THE VERTICAL PROFILE CAN MAKE BIG DIFFERENCES IN WHETHER
CONVECTION DEVELOPS. SHOULD CONVECTION BECOME FAIRLY WIDESPREAD THIS
EVENING AND CLOUD COVER REMAIN OVER THE REGION AGAIN ON
FRIDAY...THAN LOW GRADE MONSOON ACTIVITY COULD BE THE RESULT. ON THE
OTHER HAND...IF TODAY IS NOT REAL ACTIVE AND TEMPERATURES ARE ABLE
TO RISE SUFFICIENTLY DURING THE DAY TOMORROW...FRIDAY COULD TURN
INTO A MORE ACTIVE DAY. THE ECMWF AND GFS DO SHOW PWAT AND
INSTABILITY TRENDING DOWN AS THE RIDGE SHUNTS EAST AND FLOW BECOMES
DRIER...IN RESPONSE TO A TROUGH WORKING ITS WAY INTO THE PACIFIC
NORTHWEST. AS SUCH...KEPT POPS WE HAD IN OUR EARLIER PACKAGE
GOING...WITH HIGHEST VALUES IN THE HIGHER TERRAIN OF EAST CENTRAL
ARIZONA.
A SUBTLE SHIFT IN THE OVERALL CONUS FLOW PATTERN WILL TAKE PLACE
OVER THE WEEKEND...AS A PROGRESSIVE ERN PACIFIC/PAC NW TROUGH
TRANSLATES INTO SOUTHERN CANADA CAUSING A RETROGRESSION OF FEATURES
SOUTH OF THE PRIMARY NORTHERN STREAM JET. AS SUCH...AN H5 594DM
RIDGE AXIS WILL SETTLE BACK OVER ARIZONA BRINGING A SLIGHT DRYING
TREND AND MORE LARGE SCALE SUBSIDENCE. ABOVE NORMAL TEMPERATURES AND
LOWER PRECIPITATION CHANCES OUTSIDE OF SOUTHERN GILA COUNTY APPEAR
MOST LIKELY THROUGH AT LEAST MONDAY.
BOTH THE OPERATIONAL GFS AND ECMWF NOW SHOW THE AFOREMENTIONED RIDGE
AXIS PERSISTING ACROSS THE AREA MUCH LONGER THAN PREVIOUSLY
FORECAST...WITH AN INVERTED TROUGH DECAYING AND BECOMING DEFLECTED
WELL SOUTH INTO MEXICO THROUGH THE MIDDLE OF NEXT WEEK (AS OPPOSED
TO PREVIOUS FORECASTS BRINGING A CIRCULATION CENTER DIRECTLY OVER
THE FORECAST AREA). WHILE FORECAST CONFIDENCE IN NOT OVERWHELMINGLY
HIGH...THE MODEL TREND DOES SUPPORT A FORECAST TOWARDS WARMER
TEMPERATURES AND LOWER PRECIPITATION CHANCES EVEN INTO THE MIDDLE OF
NEXT WEEK. HAVE NOT YET FULLY BOUGHT INTO THE MAGNITUDE OF WARMTH
ADVERTISED BY NUMERICAL GUIDANCE...BUT HAVE CERTAINLY INCREASED
VALUES TO A NEAR NORMAL THRESHOLD.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX...KIWA AND KSDL...
SHOWERS AND THUNDERSTORMS POSSIBLE LATE THIS AFTERNOON AND EVENING
APPROACHING THE PHOENIX AIRFIELDS...MORE CONFIDENCE IN CHANCES TO
THE EAST NEAR KIWA...SO HAVE NEGLECTED TO INCLUDE MENTION IN THE
KPHX OR KSDL TAFS. DUE TO THE VERY MOIST ENVIRONMENT...CHANCES FOR
STRONG OUTFLOW WINDS AND BLOWING DUST REMAIN VERY SLIGHT TODAY.
OVERALL...WINDS TO FAVOR A WESTERLY DIRECTION FOR MOST OF THE
PERIOD.
SOUTHEAST CA AND SOUTHWEST AZ...INCLUDING KIPL AND KBLH...
SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE TO AFFECT THE AREA
THIS AFTERNOON AND EVENING HOURS...ESPECIALLY AT KBLH. OVERALL WINDS
WILL REMAIN SOUTHERLY TO SOUTHEASTERLY IN NATURE WITH PERIODIC
AFTERNOON GUSTS TO NEAR 20KTS POSSIBLE.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
A DRYING TREND WILL KEEP STORM CHANCES MAINLY CONFINED TO THE HIGHER
TERRAIN NORTH AND EAST OF PHOENIX SUNDAY AND MONDAY. MINIMUM
HUMIDITY VALUES IN THE TEENS WILL PERSIST ACROSS THE LOWER DESERTS
FOR SUNDAY AND MONDAY. BY TUESDAY OR WEDNESDAY...AFTERNOON MINIMUM
VALUES WILL IMPROVE...ONLY DROPPING INTO THE 20-30 PERCENT RANGE
WITH ANOTHER INCREASE IN MOISTURE. OVERNIGHT RECOVERY SHOULD BE GOOD
TO EXCELLENT WITH READINGS CLIMBING ABOVE 40 PERCENT MOST NIGHTS.
DAYTIME GUSTY WINDS ARE POSSIBLE EACH DAY...ALONG WITH POSSIBLE
THUNDERSTORM OUTFLOW BOUNDARY WINDS ON SATURDAY AND AGAIN TUESDAY
AND WEDNESDAY.
&&
$$
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...MCLANE/MO
AVIATION...CDEWEY
FIRE WEATHER...CDEWEY
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
216 PM MST THU JUL 11 2013
.SYNOPSIS...
FAVORABLE SOUTHERLY FLOW WILL CONTINUE TO IMPORT DEEPER MONSOON
MOISTURE INTO THE REGION OVER THE NEXT COUPLE DAYS. THIS WILL LEAD
TO MORE NUMEROUS SHOWERS AND THUNDERSTORMS ACROSS THE ENTIRE AREA
LASTING THROUGH FRIDAY. THE INCREASED MOISTURE WILL ALSO RESULT IN
COOLER DAYTIME TEMPERATURES FOR THE REST OF THE WORK WEEK. WARMER
TEMPERATURES AND A GENERAL DECREASE IN THUNDERSTORM ACTIVITY CAN BE
EXPECTED OVER THE WEEKEND AND INTO EARLY NEXT WEEK.
&&
.DISCUSSION...
SMALL DAY TO DAY CHANGES IN THE ATMOSPHERIC PROFILE CAN MAKE A WORLD
OF DIFFERENCE IN THE CONVECTIVE POTENTIAL. THIS IS CERTAINLY THE
CASE FOR THE SOUTHWEST MONSOON. ALTHOUGH IT WOULD HAVE APPEARED
YESTERDAY THAT ALL THE KEY INGREDIENTS WERE IN PLACE FOR DEVELOPMENT
OF MORE WIDESPREAD CONVECTION ACROSS THE FORECAST AREA...ONLY A FEW
STORMS MANAGED TO WORK THEIR WAY INTO EAST CENTRAL AZ DESERTS. LA
PAZ AND YUMA COUNTIES AND POINTS WEST DID SEE MORE WIDESPREAD
COVERAGE OF SHOWERS AND STORMS...WITH ADDITIONAL DYNAMICS PROVIDED
BY A LOW AND INVERTED TROUGH SWEEPING ALONG THE INTERNATIONAL
BORDER IN THE VICINITY OF THE INTERNATIONAL BORDER. THE LATEST 19Z
K1Y8 (YUMA) SOUNDING SHOWS A PROFILE RIPE FOR STORMS...WITH A STRONG
SOUTHERLY FLOW...PWAT OF 1.86 INCH...AND CAPE OF OVER 1600 J/JG.
THERE IS SOME CONVECTIVE INHIBITION...BUT THIS SHOULDN/T KEEP MORE
SHOWERS AND STORMS FROM DEVELOPING AGAIN THIS AFTERNOON AND EVENING.
A FEW SHOWERS AND STORMS ARE STILL CONTINUING IN LA PAZ AND
RIVERSIDE COUNTIES...AND THE HRRR WHICH PERFORMED THE BEST OF
MESOSCALE MODELS WITH THE EARLY MORNING CONVECTION SHOWS CONVECTION
CONTINUING IN THIS REGION FOR THE NEXT SEVERAL HOURS. MEANWHILE IN
EAST CENTRAL AZ STORMS BEGAN DEVELOPING EARLY OVER PIMA COUNTY AND
ATTEMPTED MOVED NORTH INTO PINAL COUNTY. EARLY STORMS QUICKLY
DISSIPATED BEFORE THEY COULD WORK THEIR WAY INTO THE PHOENIX
FORECAST AREA. CLOUD COVER REMAINED OVER EAST CENTRAL ARIZONA FOR
MUCH OF THE DAY. THIS KEPT TEMPERATURES SEVERAL DEGREES COOLER THAN
ON WEDNESDAY FOR MOST OF THE DAY. IN THE LAST COUPLE OF HOURS CLOUD
COVER HAS BEGUN SCATTERING OUT THOUGH...TEMPERATURES HAVE BEGUN
CLIMBING AND THE AIRMASS HAS BECOME MORE UNSTABLE. THIS WILL LIKELY
ALLOW A FEW STORMS TO WORK THEIR WAY FURTHER INTO THE DESERT
SOUTHWEST. WITH PWAT NEAR TWO INCHES...STORMS THAT DO DEVELOP HAVE
THE POTENTIAL TO PRODUCE LOCALIZED HEAVY RAINFALL. THERE REMAINS A
THREAT OF BLOWING DUST ALONG THE I-10 AND I-8 CORRIDORS IN EAST
CENTRAL ARIZONA AS OUTFLOW BOUNDARIES WORKING THEIR WAY NORTH AHEAD
OF STORMS PUSHING NORTH OUT OF PIMA COUNTY.
DO NOT HAVE GOOD CONFIDENCE IN FRIDAYS FORECAST. MOISTURE AND
INSTABILITY WILL REMAIN SUFFICIENT...THOUGH AS NOTED ABOVE LITTLE
CHANGES IN THE VERTICAL PROFILE CAN MAKE BIG DIFFERENCES IN WHETHER
CONVECTION DEVELOPS. SHOULD CONVECTION BECOME FAIRLY WIDESPREAD THIS
EVENING AND CLOUD COVER REMAIN OVER THE REGION AGAIN ON
FRIDAY...THAN LOW GRADE MONSOON ACTIVITY COULD BE THE RESULT. ON THE
OTHER HAND...IF TODAY IS NOT REAL ACTIVE AND TEMPERATURES ARE ABLE
TO RISE SUFFICIENTLY DURING THE DAY TOMORROW...FRIDAY COULD TURN
INTO A MORE ACTIVE DAY. THE ECMWF AND GFS DO SHOW PWAT AND
INSTABILITY TRENDING DOWN AS THE RIDGE SHUNTS EAST AND FLOW BECOMES
DRIER...IN RESPONSE TO A TROUGH WORKING ITS WAY INTO THE PACIFIC
NORTHWEST. AS SUCH...KEPT POPS WE HAD IN OUR EARLIER PACKAGE
GOING...WITH HIGHEST VALUES IN THE HIGHER TERRAIN OF EAST CENTRAL
ARIZONA.
A SUBTLE SHIFT IN THE OVERALL CONUS FLOW PATTERN WILL TAKE PLACE
OVER THE WEEKEND...AS A PROGRESSIVE ERN PACIFIC/PAC NW TROUGH
TRANSLATES INTO SOUTHERN CANADA CAUSING A RETROGRESSION OF FEATURES
SOUTH OF THE PRIMARY NORTHERN STREAM JET. AS SUCH...AN H5 594DM
RIDGE AXIS WILL SETTLE BACK OVER ARIZONA BRINGING A SLIGHT DRYING
TREND AND MORE LARGE SCALE SUBSIDENCE. ABOVE NORMAL TEMPERATURES AND
LOWER PRECIPITATION CHANCES OUTSIDE OF SOUTHERN GILA COUNTY APPEAR
MOST LIKELY THROUGH AT LEAST MONDAY.
BOTH THE OPERATIONAL GFS AND ECMWF NOW SHOW THE AFOREMENTIONED RIDGE
AXIS PERSISTING ACROSS THE AREA MUCH LONGER THAN PREVIOUSLY
FORECAST...WITH AN INVERTED TROUGH DECAYING AND BECOMING DEFLECTED
WELL SOUTH INTO MEXICO THROUGH THE MIDDLE OF NEXT WEEK (AS OPPOSED
TO PREVIOUS FORECASTS BRINGING A CIRCULATION CENTER DIRECTLY OVER
THE FORECAST AREA). WHILE FORECAST CONFIDENCE IN NOT OVERWHELMINGLY
HIGH...THE MODEL TREND DOES SUPPORT A FORECAST TOWARDS WARMER
TEMPERATURES AND LOWER PRECIPITATION CHANCES EVEN INTO THE MIDDLE OF
NEXT WEEK. HAVE NOT YET FULLY BOUGHT INTO THE MAGNITUDE OF WARMTH
ADVERTISED BY NUMERICAL GUIDANCE...BUT HAVE CERTAINLY INCREASED
VALUES TO A NEAR NORMAL THRESHOLD.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX...KIWA AND KSDL...
ISOLATED SHOWERS ACROSS THE METRO PHOENIX AREA SHOULD COME TO AN END
BY AROUND SUNRISE. COULD SEE ADDITIONAL SHOWERS AND THUNDERSTORMS
LATE THIS AFTERNOON AND EVENING...BUT MORE LIKELY THAN NOT THEY WILL
NOT DIRECTLY AFFECT PHOENIX TAF SITES. DUE TO THE VERY MOIST
ENVIRONMENT...CHANCES FOR STRONG OUTFLOW WINDS AND BLOWING DUST ARE
ONLY VERY SLIGHT TODAY. OVERALL...WINDS WILL FOLLOW A WESTERLY
DIRECTION FOR MOST OF THE PERIOD.
SOUTHEAST CA AND SOUTHWEST AZ...INCLUDING KIPL AND KBLH...
SHOWERS AND ISOLATED THUNDERSTORMS WILL AFFECT THE REGION THROUGH
MUCH OF THE MORNING HOURS...ESPECIALLY AT KBLH. THERE SHOULD BE A
BREAK IN THE SHOWER ACTIVITY BY LATE MORNING...BUT ADDITIONAL SHOWER
AND THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON. OVERALL WINDS
WILL REMAIN SOUTHERLY TO SOUTHEASTERLY IN NATURE WITH PERIODIC
AFTERNOON GUSTS TO NEAR 20KTS POSSIBLE.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY...
CHANCES FOR MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS
WILL REMAIN INTO THE EARLY WEEKEND...BUT A DRYING TREND WILL KEEP
STORMS MAINLY CONFINED TO THE HIGHER TERRAIN NORTH AND EAST OF
PHOENIX SUNDAY AND MONDAY. THE DRYING TREND WILL BRING MINIMUM
HUMIDITIES INTO THE TEENS ACROSS THE LOWER DESERTS FOR SUNDAY AND
MONDAY. BY TUESDAY OR WEDNESDAY...AFTERNOON MINIMUM VALUES WILL
IMPROVE...ONLY DROPPING INTO THE 20-30 PERCENT RANGE. OVERNIGHT
RECOVERY SHOULD BE GOOD TO EXCELLENT WITH READINGS CLIMBING ABOVE 40
PERCENT MOST NIGHTS. DAYTIME GUSTY WINDS ARE POSSIBLE EACH
DAY...ALONG WITH POSSIBLE THUNDERSTORM OUTFLOW BOUNDARY WINDS ON
SATURDAY AND AGAIN TUESDAY AND WEDNESDAY.
&&
$$
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...MCLANE/MO
AVIATION...KUHLMAN
FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
957 AM MST THU JUL 11 2013
.SYNOPSIS...
FAVORABLE SOUTHERLY FLOW WILL CONTINUE TO IMPORT DEEPER MONSOON
MOISTURE INTO THE REGION OVER THE NEXT COUPLE DAYS. THIS WILL LEAD
TO MORE NUMEROUS SHOWERS AND THUNDERSTORMS ACROSS THE ENTIRE AREA
LASTING THROUGH FRIDAY. THE INCREASED MOISTURE WILL ALSO RESULT IN
COOLER DAYTIME TEMPERATURES FOR THE REST OF THE WORK WEEK. WARMER
TEMPERATURES AND A GENERAL DECREASE IN THUNDERSTORM ACTIVITY CAN BE
EXPECTED OVER THE WEEKEND AND INTO EARLY NEXT WEEK.
&&
.DISCUSSION...
RADAR THIS MORNING SHOWS BROAD AREA OF WEAK CONVECTION PROPAGATING
FROM THE SOUTHEAST TO NORTHWEST OVER PORTIONS OF LA PAZ...RIVERSIDE
AND IMPERIAL COUNTIES. THIS CONVECTION IS BEING TRIGGERED IN PART BY
INVERTED TROUGH NOTED IN OUR EARLIER DISCUSSION. RADAR ESTIMATES AN
AVERAGE OF ONE AND ONE HALF INCHES HAVE FALLEN IN THIS AREA SINCE
EARLY THIS MORNING...THOUGH CURRENT RAINFALL RATES ARE AROUND 4
TENTHS OF AN INCH PER HOUR. THIS CONVECTION IS EXPECTED TO GRADUALLY
WORK ITS WAY OUT OF THE FORECAST AREA BY EARLY AFTERNOON.
MORNING SOUNDINGS FOR K1Y7 (YUMA) AND KPSR (PHOENIX) BOTH SHOW PWAT
IN EXCESS OF 2 INCHES. BOTH ALL SHOW ABUNDANT CAPE AVAILABLE FOR
STORMS TO TAP...THOUGH IN THE PHOENIX SOUNDING STILL SHOWED SOME
CAPPING AROUND 750 MB. THE PRESENCE OF THE CAP IS ALSO SUPPORTED BY
LOCAL ACARS DATA. THIS WILL NEED TO ERODE AND TEMPERATURES WILL NEED
TO RISE QUITE A BIT MORE TO SUPPORT CONVECTION OVER THE EAST CENTRAL
AZ DESERTS. DENSE CLOUD COVER OVER THE REGION COULD KEEP CONVECTIVE
TEMPERATURES FROM BEING REALIZED. IN CONTRAST...SOUTHWEST ARIZONA
AND SOUTHEAST CALIFORNIA COULD BE BETTER PRIMED FOR ANOTHER ROUND
OF STORMS THIS AFTERNOON AND EVENING. THE YUMA MORNING SOUNDING
SHOWS SIGNIFICANT COOLING IN THE MID LEVELS DURING THE LAST 24-HOURS
AND LITTLE CAPPING. DO NOT BELIEVE THIS REGION WAS WORKED OVER
ENOUGH WITH THE OVERNIGHT STORMS TO PRECLUDE A REPEAT PERFORMANCE
AGAIN TODAY.
UPDATE ALREADY OUT. BIGGEST CHANGE WAS TO REDUCE TEMPERATURES
SEVERAL DEGREES IN MANY AREAS AS OBSERVATIONS WERE TRACKING QUITE A
BIT COOLER THAN IN OUR FORECAST GRIDS. THE COOLER TEMPS ARE THE
RESULT OF THE DENSE CLOUD COVER...SHOWERS...AND STORMS. DON/T EXPECT
WE WILL SEE OUR TYPICAL DIURNAL TEMPERATURE CURVES FOR MUCH OF THE
FORECAST AREA TODAY.
&&
.PREV DISCUSSION...
ISSUED AT 430 AM MST THU JUL 11 2013
A BROAD SYNOPTIC SCALE INVERTED TROUGH CONTINUES TO PROPAGATE
WESTWARD TOWARDS THE GULF OF CALIFORNIA...WITH SMALL VORTICITY
CENTERS (POSSIBLY CONVECTIVELY ENHANCED) ALONG THE INTERNATIONAL
BORDER HELPING FORCE LARGE SCALE ASCENT AND CONVECTION THROUGH
SOUTHERN ARIZONA. DESPITE FAVORABLE MOISTURE PROFILES PER 00Z
SOUNDING DATA (DEEP WELL MIXED 11-14 G/KG OF MOISTURE)...WEAK
CAPPING AROUND 750MB STILL EXISTED PRECLUDING ORGANIZED STORMS FROM
SURVIVING OFF HIGHER TERRAIN. HOWEVER...OBJECTIVE ANALYSIS DEPICTS A
GENERAL COOLING AND MOISTENING OF THE ATMOSPHERIC COLUMN THROUGH
THE MORNING HOURS...LARGELY ERODING INHIBITION AND SUPPORTING
ISOLD/SCT SHOWER AND STORMS THROUGH MUCH OF THE CNTRL AND ERN PARTS
OF THE FORECAST AREA.
ONCE AGAIN EARLY THIS MORNING...NEAR TERM HRRR REFLECTIVITY
FORECASTS HAVE CAPTURED THE GENERAL TREND OF THE CURRENT
ACTIVITY...WITH SREF PROBABILITIES...DETERMINISTIC ECMWF...AND NMM
HIGH RESOLUTION CORE FORECASTS MOST AGGRESSIVE IN EXPANSION OF
ECHOES/QPF THROUGH SWRN ARIZONA THROUGH 18Z. GIVEN CURRENT RADAR
TENDS...COULD NOT DISCOUNT THESE MORE BULLISH SOLUTIONS...AND HAVE
RAISED POPS INTO A HIGHER CHANCE CATEGORY. MAY NEED FURTHER
REVISIONS/EXPANSION OF POPS UPDATED LATER THIS MORNING SHOULD TRENDS
CHANGE.
OTHERWISE...NOT A TREMENDOUS AMOUNT OF CONFIDENCE IN THE REMAINDER
OF THE FORECAST THIS AFTERNOON AND EVENING...PARTICULARLY REGARDING
CONVECTIVE EVOLUTION. STRANGELY...MANY OF THE MODELS TRADITIONALLY
BULLISH ON CONVECTION AND WITH HIGH FALSE ALARM RATES SHOW AN
UNUSUAL DEARTH OF RAINFALL THIS AFTERNOON/EVENING. THIS MAY BE DUE
TO AN ASSUMPTION OF CONVECTIVE CONTAMINATION AND CLOUD COVER
LINGERING OVER MUCH OF THE CWA DURING PEAK HEATING. ONE DISTINCT
TREND AMONG VIRTUALLY ALL MODELS WAS MORE FOCUS OF CONVECTION OVER
SERN CALIFORNIA...AND HAVE SUBSTANTIALLY INCREASED POPS IN THIS
REGION. INTERROGATION OF FORECAST SOUNDINGS FROM YUMA-IMPERIAL
INDICATE LOW MLCAPE...YET UNCAPPED PROFILES IN A WEAKLY SHEARED
ENVIRONMENT. WHILE ORGANIZED SEVERE STORMS WOULD NOT BE
EXPECTED...T/TD SPREADS ON THE ORDER OF 40F COULD STILL SUPPORT
ISOLD HIGHER WIND GUSTS. IN ADDITION...WHILE NOT THE CLASSIC HEAVY
RAIN SOUNDING...PWATS IN EXCESS OF 1.75 INCHES JUXTAPOSED WITH
UNIDIRECTIONAL WIND PROFILES OF LITTLE VERTICAL SPEED SHEAR MAY
SUPPORT TRAINING ECHOES AND LOCALLY HEAVY RAINFALL.
DEEP SOUTHERLY FLOW AND AMPLE MOISTURE PROFILES WILL PERSIST INTO
FRIDAY...SUGGESTING ACTIVE MONSOON THUNDERSTORM ACTIVITY.
HOWEVER...RECENT MODEL OUTPUT IS NOT PARTICULARLY IMPRESSIVE
REGARDING CONVECTIVE COVERAGE FRIDAY AFTERNOON/EVENING. AT THIS
POINT...IT APPEARS THE LACK OF A DYNAMIC TRIGGER...NEUTRAL JET
STRUCTURE...AND THE FIRST SIGNS OF A RETROGRESSIVE RIDGE MAY BE TO
BLAME. WITH MANY OF THE INGREDIENTS STILL PRESENT THROUGH THE
ATMOSPHERE...COULD NOT TOTALLY ELIMINATE THE POTENTIAL FOR AN ACTIVE
EVENING...HOWEVER HAVE GENERALLY TEMPERED BACK POPS FOR ALL BUT THE
HIGHER TERRAIN LOCATIONS.
A SUBTLE SHIFT IN THE OVERALL CONUS FLOW PATTERN WILL TAKE PLACE
OVER THE WEEKEND...AS A PROGRESSIVE ERN PACIFIC/PAC NW TROUGH
TRANSLATES INTO SOUTHERN CANADA CAUSING A RETROGRESSION OF FEATURES
SOUTH OF THE PRIMARY NORTHERN STREAM JET. AS SUCH...AN H5 594DM
RIDGE AXIS WILL SETTLE BACK OVER ARIZONA BRINGING A SLIGHT DRYING
TREND AND MORE LARGE SCALE SUBSIDENCE. ABOVE NORMAL TEMPERATURES AND
LOWER PRECIPITATION CHANCES OUTSIDE OF SOUTHERN GILA COUNTY APPEAR
MOST LIKELY THROUGH AT LEAST MONDAY.
BOTH THE OPERATIONAL GFS AND ECMWF NOW SHOW THE AFOREMENTIONED RIDGE
AXIS PERSISTING ACROSS THE AREA MUCH LONGER THAN PREVIOUSLY
FORECAST...WITH AN INVERTED TROUGH DECAYING AND BECOMING DEFLECTED
WELL SOUTH INTO MEXICO THROUGH THE MIDDLE OF NEXT WEEK (AS OPPOSED
TO PREVIOUS FORECASTS BRINGING A CIRCULATION CENTER DIRECTLY OVER
THE FORECAST AREA). WHILE FORECAST CONFIDENCE IN NOT OVERWHELMINGLY
HIGH...THE MODEL TREND DOES SUPPORT A FORECAST TOWARDS WARMER
TEMPERATURES AND LOWER PRECIPITATION CHANCES EVEN INTO THE MIDDLE OF
NEXT WEEK. HAVE NOT YET FULLY BOUGHT INTO THE MAGNITUDE OF WARMTH
ADVERTISED BY NUMERICAL GUIDANCE...BUT HAVE CERTAINLY INCREASED
VALUES TO A NEAR NORMAL THRESHOLD.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX...KIWA AND KSDL...
ISOLATED SHOWERS ACROSS THE METRO PHOENIX AREA SHOULD COME TO AN END
BY AROUND SUNRISE. COULD SEE ADDITIONAL SHOWERS AND THUNDERSTORMS
LATE THIS AFTERNOON AND EVENING...BUT MORE LIKELY THAN NOT THEY WILL
NOT DIRECTLY AFFECT PHOENIX TAF SITES. DUE TO THE VERY MOIST
ENVIRONMENT...CHANCES FOR STRONG OUTFLOW WINDS AND BLOWING DUST ARE
ONLY VERY SLIGHT TODAY. OVERALL...WINDS WILL FOLLOW A WESTERLY
DIRECTION FOR MOST OF THE PERIOD.
SOUTHEAST CA AND SOUTHWEST AZ...INCLUDING KIPL AND KBLH...
SHOWERS AND ISOLATED THUNDERSTORMS WILL AFFECT THE REGION THROUGH
MUCH OF THE MORNING HOURS...ESPECIALLY AT KBLH. THERE SHOULD BE A
BREAK IN THE SHOWER ACTIVITY BY LATE MORNING...BUT ADDITIONAL SHOWER
AND THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON. OVERALL WINDS
WILL REMAIN SOUTHERLY TO SOUTHEASTERLY IN NATURE WITH PERIODIC
AFTERNOON GUSTS TO NEAR 20KTS POSSIBLE.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY...
CHANCES FOR MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS
WILL REMAIN INTO THE EARLY WEEKEND...BUT A DRYING TREND WILL KEEP
STORMS MAINLY CONFINED TO THE HIGHER TERRAIN NORTH AND EAST OF
PHOENIX SUNDAY AND MONDAY. THE DRYING TREND WILL BRING MINIMUM
HUMIDITIES INTO THE TEENS ACROSS THE LOWER DESERTS FOR SUNDAY AND
MONDAY. BY TUESDAY OR WEDNESDAY...AFTERNOON MINIMUM VALUES WILL
IMPROVE...ONLY DROPPING INTO THE 20-30 PERCENT RANGE. OVERNIGHT
RECOVERY SHOULD BE GOOD TO EXCELLENT WITH READINGS CLIMBING ABOVE 40
PERCENT MOST NIGHTS. DAYTIME GUSTY WINDS ARE POSSIBLE EACH
DAY...ALONG WITH POSSIBLE THUNDERSTORM OUTFLOW BOUNDARY WINDS ON
SATURDAY AND AGAIN TUESDAY AND WEDNESDAY.
&&
$$
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...MCLANE/MO
AVIATION...KUHLMAN
FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS TUCSON AZ
926 AM MST THU JUL 11 2013
.SYNOPSIS...ABUNDANT MOISTURE WILL PRODUCE SCATTERED THUNDERSTORMS
THROUGH THIS EVENING WITH ISOLATED THUNDERSTORMS CONTINUING LATE
TONIGHT. THUNDERSTORM CHANCES WILL GRADUALLY DECREASE FRIDAY THROUGH
SUNDAY. THEREAFTER...ADEQUATE MOISTURE WILL CONTINUE THE CYCLE OF
MAINLY AFTERNOON AND EVENING THUNDERSTORMS MONDAY THROUGH WEDNESDAY.
COOLER DAYTIME TEMPERATURES TODAY FOLLOWED BY A WARMING TREND INTO
EARLY NEXT WEEK.
&&
.DISCUSSION...FIRST A BRIEF RECAP FROM YESTERDAY TO FORM SOME
REFERENCE FOR TODAY. THE HI RES MODELS OVERALL DID A GOOD JOB. THE
HRRR WAS A BIT UNDERDONE FOR THE AFTERNOON CONVECTION BUT DID WELL
WITH THE OVERNIGHT STORMS. THE VARIOUS WRF RUNS HANDLED THE DAYTIME
CONVECTION BETTER BUT ALL MODELS HIT PRECIP A BIT TO HARD IN TUCSON
PROPER. GRANTED MT LEMMON HAD OVER 1.5 INCHES OF PRECIP SO THE
SOLUTIONS WERE NOT TOO FAR OFF.
THAT BEING SAID...TODAY LOOKS SIMILAR TO YESTERDAY FROM A PROFILE
PERSPECTIVE. NEARLY IDENTICAL PWATS IN PLACE AND INSTABILITY
PARAMETERS ARE VERY CLOSE. THE DIFFERENCES ARE MAINLY IN THE FLOW
AND THE TEMPS ALOFT AND DCAPE IS DOWN A BIT TODAY. THE PROFILE STORM
MOTION YESTERDAY WAS SE TO NORTHWESTERLY AT 8 TO 10 KTS...AND TODAY
THE FLOW IS MORE SOUTHERLY AND A BIT STRONGER. THE SHEAR PROFILE IS
NOT AS IMPRESSIVE TODAY AND WE ARE SITTING ON THE BACK
SIDE...DOWNWARD MOTION...OF THE EXITING MCS THAT IS NOW PUSHING
NORTH TOWARD LAS VEGAS. THOSE TWO FACTORS WOULD FAVOR A LESS ACTIVE
DAY TODAY...BUT WE ARE STILL WARM AND MOIST. CONVECTIVE TEMP TODAY
SHOULD BE AROUND 92 AND WE ARE EXPECTING 95 FOR A HIGH IN TUCSON. SO
THERE ARE BOTH PROS AND CONS FOR CONVECTION TODAY.
NOW FOR THE HI RES MODELS. THE HRRR...AS MENTIONED PREVIOUSLY...IS
HANDLING THE MCS HEADING TO LAS VEGAS PRETTY WELL AND THE
INITIALIZED SKY COVER IS DOING WELL. THE U OF A NAM WRF APPEARS
SLIGHTLY TOO CLOUDY THIS MORNING OVER NORTHERN MEXICO INTO SOUTHERN
AZ...WHILE THE GFS NAM IS DOING A BETTER JOB WITH THE CLEARING.
EITHER WAY...BOTH U OF A WRF RUNS SHOWS LIMITED DAYTIME
CONVECTION...MOSTLY WEAK PULSE CONVECTION...BUT INCREASE ACTIVITY
OVER COCHISE COUNTY BY TONIGHT AFTER 10 PM ISH. THE HRRR AGREES WITH
THE WEAK DAYTIME PULSE CONVECTION BUT THE DATA ENDS AT 04Z.
I WOULD TEND TO AGREE WITH THE WEAKER DAYTIME CONVECTION GIVE OUR
POSITION ON THE SUBSIDENT SIDE OF THE EXITING MCS. HOWEVER...WATER
VAPOR IMAGERY DOES SHOW A WEAK IMPULSE CURRENTLY OVER SOUTHEAST NEW
MEXICO OR NEAR EL PASO...MOVING THIS WAY. IT LOOKS LIKE THAT FEATURE
IS MOVING AT ABOUT 25 TO 30 KTS. SO MY TERRIBLE MATH SUGGESTS THIS
FEATURE WOULD REACH SOUTHERN AZ IN ABOUT 9 TO 12 HOURS...OR SOMETIME
THIS EVENING. THIS SEEMS TO MATCH THE WRF DATA SO I WOULD TREND
TOWARD THE BETTER ACTIVITY CHANCES OCCURRING TONIGHT INTO TOMORROW
EARLY MORNING.
THAT BEING SAID...THE ABUNDANT MOISTURE...AGAIN FLOATING ABOVE THE
90TH PERCENTILE FOR THIS TIME OF YEAR...WOULD SUGGEST HEAVY RAIN
THREAT EVEN WITH THE ISOLATED CELLS THAT FORM THIS AFTERNOON.
JJB
&&
.AVIATION...GRADUAL CLEARING FROM THE SE THROUGH 11/18Z LEAVING
BEHIND SCT140 SCT-BKN350. THEN EXPECT ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS THE REGION WITH
ISOLD MVFR CONDS. A BASIC DIURNAL WIND PATTERN IS EXPECTED AWAY FROM
THUNDERSTORMS WITH ERRACTIC AND GUSTY WINDS NEAR THUNDERSTORMS.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...SCATTERED MAINLY LATE AFTERNOON THROUGH EARLY
MORNING SHOWERS AND THUNDERSTORMS WILL CONTINUE WITH A SLIGHT
DIMINISHING TREND INTO THE WEEKEND. THE STRONGER THUNDERSTORMS WILL
PRODUCE GUSTY AND ERRATIC WINDS AND LOCALLY HEAVY RAINS. OUTSIDE OF
THE THUNDERSTORM ACTIVITY...GENERALLY NORMAL DIURNAL WIND TRENDS ARE
EXPECTED TO OCCUR THROUGH THE WEEKEND. DAYTIME RELATIVE HUMIDITIES
WILL RANGE FROM THE 20S TO 30S WITH GOOD NIGHTTIME RECOVERIES
THROUGH FRIDAY THEN THERE WILL BE A SLIGHT DRYING TREND INTO THE
WEEKEND.
&&
.PREV DISCUSSION...SCATTERED SHOWERS AND ISOLATED TSTMS ONGOING FROM
THE TUCSON METRO AREA WESTWARD TO NORTHWESTWARD INTO WRN PIMA/SOUTH
CENTRAL PINAL COUNTIES. BULK OF THIS ACTIVITY IS EXPECTED TO MOVE
OUT OF THIS FORECAST AREA AROUND 14Z. HOWEVER...THE 11/08Z RUC HRRR
DEVELOPS PRECIP ECHOES ACROSS CENTRAL/ERN PIMA COUNTY BY 17Z.
PRECIP CELLS ARE PROGGED TO BECOME MORE WIDESPREAD BY EARLY THIS
AFTERNOON AND ARE DEPICTED TO BE MOSTLY NORTH AND EAST OF TUCSON BY
22Z. THE OFFICIAL FORECAST DEPICTS SCATTERED SHOWERS/TSTMS FROM LATE
THIS MORNING INTO THIS EVENING. HAVE MAINTAINED A SLIGHT CHANCE OF
SHOWERS/TSTMS AREA-WIDE LATE TONIGHT.
11/00Z GFS/ECMWF GENERALLY AGREE THAT UPPER HIGH CENTERED OVER THE
CENTRAL CONUS PLAINS FRI-SAT WILL MOVE TOWARD THE FOUR CORNERS
REGION EARLY NEXT WEEK. GFS/ECMWF DEPICT A GRADUAL DECREASE IN MID-
LEVEL MOISTURE THIS WEEKEND. THUS...SCATTERED AFTERNOON AND EVENING
SHOWERS/TSTMS FRI-SAT ARE FORECAST TO DECREASE IN COVERAGE SUN.
THERE WILL STILL BE ENOUGH MOISTURE FOR ISOLATED-SCATTERED SHOWERS/
TSTMS SUN AFTERNOON AND SUN EVENING.
THEREAFTER...SCATTERED MAINLY AFTERNOON AND EVENING SHOWERS/TSTMS
WILL RETURN MON-WED AS THE UPPER HIGH REMAINS QUASI-STATIONARY NEAR
THE FOUR CORNERS REGION. HAVE NOTED THAT THE 11/00Z GFS/ECMWF WERE
MARKEDLY FURTHER SOUTH WITH THE PATH OF AN UPPER LEVEL LOW PRESSURE
SYSTEM VERSUS PREVIOUS SOLUTIONS. THUS...HAVE TRIMMED POPS SOMEWHAT
PARTICULARLY NEXT MON.
HIGH TEMPS TODAY WILL AVERAGE ABOUT 2-5 DEGS F COOLER VERSUS WED. A
WARMING TREND WILL THEN OCCUR FRI-MON FOLLOWED BY COOLER DAYTIME
TEMPS TUE-WED.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
DISCUSSION...BROST
AVIATION/FIRE WEATHER...CERNIGLIA
AREA FORECAST DISCUSSION
NWS MIAMI FL
245 PM EDT THU JUL 11 2013
.SHORT TERM (TONIGHT-SATURDAY NIGHT)...
RECENTLY ANIMATED WATER VAPOR LOOP SHOWED PLENTY OF MID/UPPER
MOISTURE ASSOCIATED WITH THE REMNANTS OF CHANTAL LOCATED OVER
EASTERN CUBA AND THE BAHAMAS EAST OF AN UPPER LOW CENTERED ACROSS
THE FLORIDA STRAITS. THE LATEST VISIBLE SATELLITE IMAGERY SHOWED
PLENTY OF CONVECTION CONTINUING TO FLARE BETWEEN JAMAICA AND EASTERN
CUBA EARLY THIS AFTERNOON NEAR A REMNANT TROUGH OF LOW PRESSURE. THE
12Z GFS RUN NOW INDICATES A WEAK SFC LOW DEVELOPING AND LIFTING
NORTH FROM THIS GENERAL AREA OVER THE GULF STREAM JUST EAST OF THE
FLORIDA PENINSULA TONIGHT THROUGH THE DAY FRIDAY WITH THE BULK OF
THE MOISTURE/RAINFALL PROJECTED TO REMAIN TO ITS EAST OVER THE
BAHAMAS. ALTHOUGH CONFIDENCE REMAINS LOW...REGENERATION IS CERTAINLY
NOT OUT OF QUESTION AND ALL INTERESTS ARE ENCOURAGED TO MONITOR THE
LATEST FORECAST AS UPDATES MAY BECOME NECESSARY OVER THE UPCOMING 24
HRS. REGARDLESS OF ANY FURTHER DEVELOPMENT...DAYTIME HEATING
COMBINED WITH THE DEEP LAYER FLOW SHIFTING TO THE WSW WILL FAVOR
CONVECTION INITIATING AND SETTING UP ACROSS THE EAST COAST METRO AND
COASTAL LOCATIONS THROUGH THE AFTERNOON/EVENING PERIODS...ESPECIALLY
ACROSS BROWARD AND PALM BEACH COUNTIES. ON SATURDAY...THE SFC LOW IS
FORECAST TO CONTINUE NORTH THEN NORTHWEST AND ASHORE SOMEWHERE ALONG
THE SC/GA COAST SATURDAY NIGHT. THE GFS PWAT SOLUTIONS INDICATE
VALUES INCREASING TO AROUND THE 2" MARK THROUGH THIS TIME SATURDAY
ACROSS SOUTH FLORIDA. THIS COMBINED WITH THE DEEP SOUTHWEST FLOW
WILL KEEP THE BEST RAIN CHANCES FOCUSED OVER THE EASTERN HALF OF THE
PENINSULA. ALTHOUGH A FEW STRONG STORMS WITH GUSTY WINDS UP TO 40-50
MPH WILL CERTAINLY REMAIN POSSIBLE EACH AFTERNOON...THE MAIN CONCERN
WILL BE THE POTENTIAL FOR LOCALIZED HEAVY RAIN AND URBAN FLOODING
OVER THE HEAVILY POPULATED EAST COAST/METRO AREAS EACH DAY.
.LONG TERM (SUNDAY-THURSDAY)...
THE ATLANTIC RIDGE WILL BEGIN TO BUILD IN NORTH OF THE AREA
SUNDAY, WITH STEERING FLOW TURNING MORE EASTERLY. AN EASTERLY
WIND FLOW IS THEN EXPECTED TO PREVAIL NEXT WEEK. BOTH GFS/ECMWF
SHOW AN INVERTED LOW-MID LEVEL TROUGH MOVING ACROSS FLORIDA DURING
THE EARLY-MIDDLE PART OF NEXT WEEK. THIS COULD ENHANCE SHOWER AND
THUNDERSTORM ACTIVITY SOMEWHAT, BUT FOR NOW FOLLOWED GFS MOS WITH
ONLY CHANCE POPS THROUGH THE LONG TERM PERIOD.
57/GREGORIA
&&
.AVIATION...
SCATTERED SHOWERS AND THUNDERSTORMS CONTINUE TO FIRE ACROSS MAINLY
THE INTERIOR THIS AFTERNOON FUELED BY SEA BREEZES FROM BOTH THE
ATLANTIC AND GULF. LATEST HRRR AND LOCAL HIGH RESOLUTION MODELS KEEP
THE VAST MAJORITY OF THE ACTIVITY ACROSS INLAND AREAS AND AWAY FROM
THE TAF SITES. DID KEEP VCSH IN AT ALL SITES THROUGH THE AFTERNOON
AND EARLY EVENING. COULD NOT RULE OUT AN ISOLATED TSRA AFFECTING A
TAF SITE BUT NOT CONFIDENT ENOUGH TO CARRY MENTION IN TAFS ATTM.
&&
.MARINE...
A SURFACE TROUGH OF LOW PRESSURE WILL LIFT NORTH OVER THE ATLANTIC
WATERS THROUGH THE DAY FRIDAY WITH LIGHT TO MODERATE SOUTH AND
SOUTHWEST FLOW FILLING IN ACROSS THE MARINE AREAS IN ITS WAKE FRIDAY
NIGHT INTO THE WEEKEND. SCATTERED SHOWERS AND STORMS ASSOCIATED WITH
THIS FEATURE...ESPECIALLY ALONG THE EAST COAST EACH AFTERNOON AND
EVENING...COULD LEAD TO PERIODS WITH REDUCED VISIBILITIES...GUSTY
WINDS AND LOCALLY CHOPPIER CONDITIONS IN AND AROUND THE HEAVIER
ACTIVITY.
&&
.FIRE WEATHER...
NO CONCERNS AS RELATIVE HUMIDITIES ARE FORECAST TO REMAIN ABOVE
CRITICAL LEVELS EACH DAY. THE FLOW WILL SHIFT TO THE SOUTHWEST
FRIDAY THROUGH THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 76 89 75 88 / 20 60 30 60
FORT LAUDERDALE 77 89 78 89 / 20 60 30 60
MIAMI 77 89 77 88 / 20 60 30 60
NAPLES 73 87 74 89 / 20 30 30 40
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...85/AG
LONG TERM...57/GREGORIA
AVIATION/RADAR...10/CD
AREA FORECAST DISCUSSION
NWS WICHITA KS
104 PM CDT THU JUL 11 2013
.UPDATE...
ISSUED AT 1255 PM CDT THU JUL 11 2013
MAINTAINED WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ACROSS
PORTIONS OF CENTRAL AND SOUTH CENTRAL KANSAS THROUGH AROUND 21Z
WITH REMNANT MESOSCALE VORTICITY CENTER OVER EAST CENTRAL KS BEFORE
THE ACTIVITY IS EXPECTED TO SLOWLY DIMINISH. DUE TO WIDESPREAD
RAIN AND CLOUD COVER...TRENDED HIGH TEMPERATURES DOWN WITH SOME
LOCATIONS STRUGGLING TO REACH 90. A STABLE AIRMASS IS ANTICIPATED
IN THE WAKE OF THE MORNING MCS WITH CLEARING SKIES LATER THIS
AFTERNOON.
MWM
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 400 AM CDT THU JUL 11 2013
TODAY:
(+)TSRA CLUSTER CONTINUES OVER SW NEBRASKA/NW KS BORDER FROM ~KMCK SE
OVER DECATUR & NORTON COUNTIES. ANOTHER (+)TSRA THAT DEVELOPED OVER
ERN OSBORNE COUNTY IS STATIONARY. TSRA BEING SUSTAINED BY STRONG DEEP
ISENTROPIC ASCENT FROM 305-315K LAYER INDUCED BY BROAD HIGH PRESSURE
COVERING MOST OF UPR MS VALLEY & WEAK LOW PRESSURE SITUATED NEAR CO/KS
BORDER...FROM WHICH A WEAK NEARLY STATIONARY FRONT EXTENDS SE ACROSS
SW KS TO NRN OK. WELL-DEFINED RICH LWR-DECK MOISTURE AXIS IS ORIENTED
IN NW-SE MANNER ALONG & JUST NE OF THE BOUNDARY TO ALONG THE W/SW
CORRIDOR OF KICT COUNTRY. GREATEST CHANCES FOR TSRA TO THEREFORE OCCUR
OVER WRN HALF OF KICT COUNTRY THIS MORNING. HRRR DEPICTING A SIMILAR
PATTERN & AS SUCH HAVE INCREASED POPS TO 35-40% OVER THAT PART OF
CNTRL KS W OF I-135. AS LWR-DECK TROFFING GETS BETTER ESTABLISHED LWR
DECK FLOW TO BECOME MORE SLY WHICH WOULD REALIGN LWR-DECK MOISTURE
AXIS TO N-S ORIENTATION. WITH STRONG MASSIVE MID-UPR HIGH INCREASING
DOMINANCE FROM THE SRN TOWARD THE NRN PLAINS THE RESULTING INCREASED
SUBSIDENCE WOULD INHIBIT FURTHER TSRA DEVELOPMENT THIS AFTERNOON.
THE ALREADY STRONG MASSIVE HIGH PRESSURE BECOMES EVEN MORE SO OVER THE
NEXT 3 DAYS & WITH LWR-DECK TROFFING INCRESING OVER THE WRN PLAINS THE
FURNACE WILL REMAIN TURNED UP THRU SATURDAY. HIGHS ~100F ARE LIKELY
ALONG THE WRN CORRIDOR FRI & SAT WHERE HEAT INDICES ~105F ARE POSSIBLE.
AS SUCH A HEAT ADVISORY MAY BE REQUIRED...ESPECIALLY FRI. STAY TUNED.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 355 AM CDT THU JUL 11 2013
TYPICAL MID-SUMMER STILL ANTICIPATED THROUGHOUT THESE PERIODS. HOWEVER
MID-RANGE MODELS (MORE SO THE GFS) DEPICT A MID-UPR LOW PRESSURE AREA
RETROGRADING ACROSS THE MID-MS VALLEY TOWARD...THEN ACROSS...THE MO/KS
BORDER ON MON. FOR NOW HAVE DRY FORECAST INTACT BUT THE BEHAVIOR OF THE
UNORTHODOX LOW WILL REQUIRE INCREASED ATTENTION LATER THIS WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1255 PM CDT THU JUL 11 2013
A LARGE AREA OF SHOWERS AND THUNDERSTORMS RESULTED IN TRANSIENT AREAS
OF MVFR ACROSS PORTIONS OF CENTRAL AND SOUTH CENTRAL KANSAS
THROUGH THE MORNING HOURS. HOWEVER VFR HAS RETURNED ACROSS THE AREA
AND IS EXPECTED TO PERSIST THROUGH THE 24-HR PERIOD. SEVERAL
OUTFLOW BOUNDARIES HAVE ALLOWED GUSTY NORTHEAST WINDS TO
DEVELOP...HOWEVER WIND DIRECTION IS EXPECTED TO VEER TO THE
SOUTHEAST AS THE PBL BECOMES MIXED.
MWM
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 91 72 99 77 / 20 30 0 0
HUTCHINSON 92 72 100 77 / 30 20 0 0
NEWTON 90 71 97 76 / 30 30 0 0
ELDORADO 90 71 97 75 / 40 30 0 0
WINFIELD-KWLD 92 73 99 76 / 30 30 0 0
RUSSELL 95 72 102 77 / 50 10 0 0
GREAT BEND 95 73 102 77 / 30 10 0 0
SALINA 90 72 101 77 / 100 30 0 0
MCPHERSON 91 72 100 77 / 60 20 0 0
COFFEYVILLE 93 71 97 73 / 10 20 0 0
CHANUTE 91 69 95 71 / 10 10 0 0
IOLA 90 68 94 71 / 10 10 0 0
PARSONS-KPPF 92 70 95 72 / 10 20 0 0
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1240 PM CDT THU JUL 11 2013
.UPDATE...
ISSUED AT 630 AM CDT THU JUL 11 2013
A VERY NARROW BAND OF MODERATE INSTABILITY APPEARS TO EXIST JUST
AHEAD OF A SHORT WAVE TROUGH MOVING INTO CENTRAL KANSAS. THE TIGHT
GRADIENT IN INSTABILITY SEEMS TO EXIST BETWEEN CONCORDIA WHERE
INSTABILITY IS MINIMAL AND SALINA WHERE RAP SOUNDINGS SUGGEST 1500
J/KG OF ELEVATED CAPE. SHORT TERM HI-RES MODELS SUGGEST THAT THE
WINDOW FOR THIS ELEVATED INSTABILITY IS FAIRLY SMALL NOT ONLY
SPATIALLY BUT ALSO IN TIME...AND WOULD EXPECT STORMS TO DIMINISH
IN COVERAGE AND INTENSITY THROUGH 9 AM. MAY SEE A FEW LINGERING
STORMS BEYOND 9 AM...BUT MOST INFORMATION POINTS TO DISSIPATION OF
ALL ACTIVITY BEFORE NOON. SO FAR...THE ONLY STORM TO POSE A SEVERE
RISK WAS OVER LINCOLN COUNTY IN A CELL THAT EXHIBITED MID LEVEL
ROTATION FOR 20 MINUTES OR SO AND INTENSIFIED ACCORDINGLY. THE
LIKELIHOOD OF THIS HAPPENING AGAIN IS LOW BUT NON-ZERO. ANY STRONG
STORMS WOULD POSE A RISK OF MARGINALLY SEVERE HAIL AND LOCALIZED
DOWNBURST WINDS AS THEY COLLAPSE. THE SLOW MOVEMENT OF THIS
ACTIVITY ALSO POINTS TO A LOCALIZED HEAVY RAINFALL POTENTIAL.
BARJENBRUCH
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM CDT THU JUL 11 2013
A WEAK SHORT WAVE TROUGH EVIDENT IN WV IMAGERY AND MID LEVEL WIND
PROFILES WAS MOVING TO THE SOUTHEAST OUT OF SOUTHWEST NEBRASKA AT 3
AM. SEVERAL CLUSTERS OF THUNDERSTORMS WERE ONGOING OVER THE HIGH
PLAINS IN CONJUNCTION WITH THIS SYSTEM BUT WILL REMAIN WELL WEST OF
THE LOCAL FORECAST AREA. EAST OF THIS SYSTEM...FAIRLY WEAK LOW LEVEL
SOUTHERLY FLOW WAS BEING PULLED INTO CENTRAL KANSAS...RESULTING IN
WEAK BUT DEEP ISENTROPIC ASCENT. THIS ASCENT WAS WORKING WITH WEAK
ELEVATED INSTABILITY TO SPARK ISOLATED SHOWERS IN NORTH CENTRAL
KANSAS. THE ASCENT...AND THUS THE ISOLATED SHOWER ACTIVITY...SHOULD
PERSIST OVER NORTH CENTRAL KANSAS INTO THE MID MORNING HOURS WITH AN
OUTSIDE CHANCE FOR A FEW LIGHTNING STRIKES AS WELL ALTHOUGH THE
STRONGER INSTABILITY SEEMS TO BE WEST OF THE FORECAST AREA. ANY
PRECIP IS EXPECTED TO COME TO AN END BY NOON...WITH DRY CONDITIONS
EXPECTED THROUGH THE REST OF TODAY AND TONIGHT. TEMPERATURES SHOULD
WARM UP NICELY AGAIN TODAY AFTER MORNING LOWS IN THE UPPER 60S...AND
EXPECT HIGHS IN THE UPPER 80S TO LOWER 90S. MOSTLY CLEAR SKIES WILL
ALLOW A QUICK COOL DOWN THIS EVENING...AND WHILE A SOUTH BREEZE
SHOULD KEEP NORTH CENTRAL KANSAS IN THE UPPER 60S TO LOWER
70S...LIGHTER WINDS IN EASTERN KANSAS SHOULD CONTRIBUTE TO LOW TEMPS
IN THE MIDDLE 60S.
BARJENBRUCH
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 333 AM CDT THU JUL 11 2013
MAIN MID LEVEL FEATURE BEING THE EXPANSIVE MID LEVEL RIDGE OVER THE
SOUTHWEST CONUS IS EXPECTED TO FINALLY MIGRATE EAST AS AN UPPER
SHORTWAVE TROUGH SETTLES AND BECOMES CUTOFF FROM THE MAIN FLOW
THROUGH THE WEEKEND. LATEST GFS TRIES TO BRING IN SOME SPOTTED
QPF TOWARDS THE NORTH CENTRAL AREAS ON FRIDAY MORNING...HOWEVER
WITH NO CLEAR LACK OF FORCING HAVE DECIDED TO LEAVE DRY AT THIS
TIME. MAIN STORY THEN TURNS TO THE HEAT AS A SURFACE TROUGH
SITUATED OVER EASTERN COLORADO WILL PROVIDE DECENT SOUTHWEST FLOW
AND AMPLE WARM ADVECTION. KEPT TRENDS IN PLACE WITH WARMEST HIGHS
FRIDAY NEAR 100 DEGREES OVER NORTH CENTRAL KS COINCIDING WITH
PROXIMITY OF THERMAL AXIS. SLIGHTLY COOLER TEMPS IN THE LOW 90S
EXPECTED FOR THE EAST CENTRAL/NORTHEAST AREAS...HOWEVER WITH
DEWPOINT VALUES IN THE 60S ADVECTING INTO THE AREA WILL MAKE IT
FEEL NEAR THE CENTURY MARK OR A FEW DEGREES HIGHER FRIDAY INTO
SATURDAY. LITTLE CHANGE OCCURS FOR SATURDAY EXCEPT WARM LOWS
SATURDAY MORNING IN THE 70S WILL ALLOW TEMPS ONCE AGAIN TO RISE TO
THE CENTURY MARK OVER NORTH CENTRAL KS. NOTING TRENDS AND
PERFORMANCE OF THE GFS AND NAM MOS GUIDANCE LEAD TO GOING A FEW
DEGREES ABOVE OUTPUT FOR HIGHS ON FRIDAY/SATURDAY.
UNCERTAINTY INCREASES STEADILY AS WE HEAD INTO THE EXTENDED PERIOD.
LATEST RUNS OF THE GFS/ECMWF PUSH THE H5 RIDGE BACK WEST AS THE
CLOSED TROUGH OVER THE NORTHEAST CONUS RETROGRADES WESTWARD
INFLUENCED BY ANOTHER RIDGE BUILDING OVER THE ATLANTIC. POSITION AND
WESTERN EXTENT OF THIS TROUGH MAY MEAN THE DIFFERENCE BETWEEN A VERY
WET OR DRY PERIOD. IF THE CURRENT GFS/ECMWF CAME TO FRUITION WE MAY
SEE PERIODS OF SHOWERS AND THUNDERSTORMS THROUGHOUT NEXT
WEEK...GREATLY IMPACTING THE TEMPERATURES IN CURRENT FORECAST. SINCE
THIS SCENARIO HAS NOT BEEN CONSISTENT WITH RECENT SOLUTIONS WILL
KEEP A DRY FORECAST FOR NOW ASSUMING THE RIDGE INFLUENCES THE AREA
WITH THE TROUGH POSITIONED FURTHER EAST. WILL MONITOR IN THE
UPCOMING FORECASTS AND MAKE CHANGES IF NEEDED. SURFACE HIGH PRESSURE
IN PLACE WILL KEEP TEMPERATURES NEAR THE NORMAL VALUES IN THE LOW TO
MID 90S FOR HIGHS AND LOWS IN THE UPPER 60S TO LOW 70S THROUGH
THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1240 PM CDT THU JUL 11 2013
VFR CONDITIONS EXPECTED THROUGH THE PERIOD. WINDS EAST AROUND 10
KTS THROUGH 01Z THEN BECOMING LIGHT. WINDS WILL INCREASE FROM THE
SOUTHEAST BY 15Z FRIDAY TO AROUND 12KTS WITH SOME GUSTS NEAR
21 KTS BY 18Z. CONVECTION IS EXPECTED TO REMAIN SOUTHWEST OF THE
TERMINALS.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BARJENBRUCH
SHORT TERM...BARJENBRUCH
LONG TERM...BOWEN
AVIATION...53
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1206 PM CDT THU JUL 11 2013
...UPDATED SYNOPSIS AND AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 1204 PM CDT THU JUL 11 2013
AT 12Z THURSDAY A +110KT 250MB JET EXTENDED FROM NORTHERN
CALIFORNIA INTO NORTHWEST MONTANA. THIS WAS LOCATED ON THE
NORTHWEST SIDE OF AN UPPER LEVEL LOW THAT WAS CENTERED OVER NEW
MEXICO BASED ON THE 500MB ANALYSIS. AN UPPER LEVEL RIDGE AXIS
EXTENDED FROM NEW MEXICO NORTH INTO CENTRAL CANADA. A 500MB LOW
WAS LOCATED OVER BRITISH COLUMBIA. 700MB TEMPERATURES AT 12Z
THURSDAY RANGED FROM +4C AT DODGE CITY TO +7C AT NORTH PLATTE AND
AMARILLO TO +16C AT DENVER. A WEDGE OF HIGHER DEWPOINTS APPEAR
EXTEND FROM AMARILLO TO NORTH PLATTE WHICH WAS NEAR THE +12C
ISOTHERM. A 850MB HIGH WAS LOCATED OVER EASTERN KANSAS. WEST OF
THIS HIGH THE WINDS WERE FROM THE SOUTH AND DEWPOINTS RANGED FROM
+9 AT DODGE CITY TO +11C AND AMARILLO AND +17C AT NORTH PLATTE. A
SURFACE BOUNDARY EARLIER THIS MORNING EXTENDED FROM NORTHEAST
COLORADO INTO NORTHWEST OKLAHOMA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 358 AM CDT THU JUL 11 2013
THE SURFACE FRONT THAT WAS LOCATED ACROSS SOUTHWEST KANSAS
WEDNESDAY AFTERNOON WAS GETTING ANOTHER BOOST SOUTHWARD FROM
OVERNIGHT THUNDERSTORM OUTFLOW. UPPER LEVEL RIDGING WILL BE EDGING
BACK OVER THE CENTRAL PLAINS OVER THE NEXT 24 TO 36 HRS. HOWEVER,
THE EFFECTIVE FRONTAL BOUNDARY MAY BE SLOW TO MOVE BACK TO THE NORTH
TODAY. INSTEAD OF MORE OF A SOUTHERLY WIND PER THE NAM MODEL, WITH
TEMPERATURES REACHING 100-102F, MORE OF A SOUTHEASTERLY UPSLOPE WIND
MAY SERVE TO KEEP TEMPERATURES FROM REACHING 100F PER RAP MODEL
(WITH MID TO UPPER 90S MORE LIKELY. IN ADDITION, ANY ONGOING
CONVECTION OVER SOUTH CENTRAL AND CENTRAL KANSAS THIS MORNING COULD
HELP KEEP TEMPERATURES COOLER ALONG A MEDICINE LODGE TO HAYS
CORRIDOR THIS AFTERNOON DUE TO OUTFLOW FROM THE SOUTHEAST. KEEP
IN MIND THAT LEE TROUGHING WILL BE STRENGTENING IN THE LEE OF THE
ROCKIES THIS AFTERNOON IN REPONSE TO STRONG SOUTHWEST MID LEVEL
FLOW ACROSS THE NORTHERN ROCKIES. THIS WOULD TEND TO PROMOTE
MORE OF A SOUTH WIND AND HOTTER TEMPERATURES FOR TODAY. SO DESPITE
THE OUTFLOW, I WOULD NOT BE SURPRISED IF TEMPERATURES ROSE TO OVER
100 DEGREES IN DODGE CITY BY THIS AFTERNOON--HENCE THE FORECAST
UNCERTAINTY. BY LATE AFTERNOON, A CORRIDOR OF 2000 J/KG SURFACE
BASED CAPE WILL BE SITUATED FROM DODGE CITY TO DIGHTON AND SCOTT
CITY. ISOLATED THUNDERSTORMS CANNOT BE RULED OUT. UPPER LEVEL WINDS
WILL BE QUITE A BIT WEAKER TODAY THAN ON WEDNESDAY ALONG THE
INTERSTATE 70 CORRIDOR SO THAT ANY HAIL WOULD BE QUARTER SIZE OR
SMALLER. ANY CONVECTION THAT DEVELOPS LATE THIS AFTERNOON SHOULD
WEAKEN THIS EVENING WITH THE LOSS OF DAYTIME HEATING GIVEN THE LACK
OF UPPER LEVEL SUPPORT. TEMPERATURES TONIGHT WILL BE HELD UP BY
SOUTH WINDS, WITH LOWS IN THE LOWER TO MID 70S.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 254 AM CDT THU JUL 11 2013
A RETURN TO HOT AND DRY CONDITIONS IS FORECAST FOR FRIDAY SATURDAY
AND POSSIBLY BEYOND, AS AN UPPER HIGH PRESSURE RIDGE ROTATES INTO THE
HIGH PLAINS REGION AND BECOMES STATIONARY FOR A FEW DAYS. FORECAST
MODELS DO SHOW CONSIDERABLE SPREAD FROM AROUND 100 DEGREES INTO THE
MID 100`S BOTH DAY AS THE WARM BOUNDARY LAYER PLUME OVERSPREAD THE
AREA WITH 27-30 DEGREES C 850 MB AIR. IF THE WARMEST OF FORECAST
SOLUTIONS VERIFY ACROSS CENTRAL KANSAS, DANGEROUS HEAT INDICES COULD
BE ACHIEVED IN THE AFTERNOON. THE PATTERN BECOMES MORE FLATTENED
AFTER FRIDAY, AND JUST HOW WARM THE HIGHS GET IN THE AFTERNOON ARE
LESS CLEAR. BY MONDAY, THE ECMWF SHOWS A FRONT IN THE VICINITY OF
NORTHWEST KANSAS AND SW NEBRASKA. THAT KIND OF PATTERN WOULD
RELEGATE STORMS TO THE FRONT WITH A LACK OF STEERING FLOW. A RESULT
OF THE NEARLY STATIONARY UPPER HIGH WILL BE SURFACE WINDS BECOMING
MORE LIGHT AND VARIABLE WITH TIME AS THE SUBSIDENCE INDUCED SURFACE
HIGH MAINTAINS INCREASING HIGH PRESSURE FROM THE NORTHERN PLAINS.
LIGHT AND VARIABLE OR LIGHT EASTERLY FLOW WOULD SUPPORT NOT AS HOT
TEMPERATURES IN THE MID TO UPPER 90S AND LOWER FREQUENCIES OF 100
DEGREE AND HIGH READINGS. ISOLATED ELEVATED THUNDERSTORMS CAN`T BE
RULED OUT COMPLETELY MID TO LATE WEEK AS MODELS SHOW A SUBTLE SIGNAL
OF MID LEVEL MOISTURE SPREADING NORTHWARD ON THE BACK SIDES OF THE
UPPER HIGH PRESSURE. CONFIDENCE IS TOO LOW HOWEVER TO RAISE THE
CURRENT ALLBLEND APPROACH OF SINGLE DIGIT PRECIPITATION
PROBABILITIES DURING THIS TIMEFRAME. .
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1204 PM CDT THU JUL 11 2013
A WEAK SURFACE BOUNDARY WILL LIFT NORTHEAST ACROSS WESTERN KANSAS
THROUGH THE LATE AFTERNOON. AS THIS BOUNDARY PASSES...SOUTHERLY
WINDS WILL DEVELOP WITH LIGHT WINDS INCREASING TO NEAR 15 MPH BY
LATE DAY. A FEW LATE DAY CLOUDS WILL BE POSSIBLE AND BASED ON THE
LATEST BUFR SOUNDING TH CLOUD BASES WILL BE AT OR ABOVE 5000 FT.
AS A RESULT VFR CONDITIONS ARE EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 99 74 104 74 / 20 10 0 0
GCK 99 74 104 73 / 20 20 0 0
EHA 98 73 103 71 / 10 10 0 0
LBL 99 74 104 73 / 20 10 0 0
HYS 97 75 104 75 / 20 20 0 0
P28 97 75 102 75 / 20 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...FINCH
LONG TERM...RUSSELL
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1100 AM MDT THU JUL 11 2013
.UPDATE...
ISSUED AT 549 AM MDT THU JUL 11 2013
LESS CONVECTION AROUND AT THIS TIME THAN PREVIOUSLY ANTICIPATED.
THERE STILL OUTFLOW BOUNDARIES AROUND SO LEFT IN A 20 TO 30
PERCENT CHANCE THROUGH 15Z. ALSO ADJUSTED SKY COVER AND WINDS
BASED ON LATEST TRENDS.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 415 AM MDT THU JUL 11 2013
FORECAST CONCERNS WILL BE CHANCE OF THUNDERSTORMS FOLLOWED BY HOW
HOT DOES IT GET ALONG WITH POSSIBLE HEAT HIGHLIGHTS. SATELLITE
SHOWING A RATHER AMPLIFIED PATTERN FROM THE PACIFIC IN CENTRAL NORTH
AMERICA. MOISTURE AND WEAK SHORTWAVE TROUGHS ROTATING AROUND UPPER
HIGH CENTERED TO OUR SOUTH/SOUTHWEST. FRONTAL BOUNDARY AT THIS TIME
REMAINS DRAPED TO OUR SOUTH AND WEST.
AT MID LEVELS...THE UKMET FOLLOWED BY THE CANADIAN AND GFS WERE
DOING BEST ON WHERE THE CENTER OF THE MID/UPPER HIGH WAS AND THE
RESULTING HEIGHT FIELD OVER THE AREA. OUTFLOW BOUNDARIES ARE
MESSING UP THE WIND FIELD RIGHT AND THE HRRR HAS THE RIGHT IDEA ON
IT. UKMET AND CANADIAN WERE DOING A LITTLE BETTER THAN THE GFS AND
ECMWF ON THE LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...HOW MUCH THUNDERSTORM ACTIVITY WILL BE AROUND THIS
MORNING AND LINGERING MESOSCALE AFFECTS FROM THESE THUNDERSTORMS WILL
BE AROUND FOR THE ENTIRE DAY ARE THE BIG QUESTIONS WHICH MAY BE VERY
HARD TO ANSWER. PERSISTENT CLUSTER OF THUNDERSTORMS REMAINS OVER THE
EASTERN PORTION OF THE AREA. THIS AREA WAS THE RESULT A WEAK
SHORTWAVE IN THE AREA BUT MOST OF ALL THE COLLISION OF OUTFLOW
BOUNDARIES. OUTFLOW BOUNDARIES ABOUND ACROSS THE AREA PER RADAR AND
SURFACE OBSERVATIONS AND ESPECIALLY IN THE EASTERN AND CENTRAL
PORTION. ELEVATED CAPE AND LACK OF STRONG ELEVATED CINH WILL BE
AROUND AT THE BEGINNING OF THE DAY. ADDITIONAL DEVELOPMENT IS
OCCURRING AND IS EXPECTED TO CONTINUE TO OCCUR. SO ISSUED THE ZONES
WITH A PRE-FIRST PERIOD AND KEPT POPS AROUND IN THE MORNING...
ESPECIALLY IN THE EAST. WILL CONTINUE TO MONITOR AND WILL ISSUE AN
UPDATE NEAR 12Z TO ACCOUNT FOR THE LATEST TRENDS WHICH THE MODELS ARE
PLAYING CATCH UP WITH.
NOT ACCOUNTING FOR MESOSCALE INFLUENCES OVERNIGHT GUIDANCE HAD THE
HIGHEST INSTABILITY AND LOWEST 700 MB TEMPERATURES IN THE EASTERN
PORTION OF THE AREA. AT 500 MB WEAK SHORTWAVE IS MOVING ACROSS THE
EASTERN HALF IN THE AFTERNOON. AT 700 MB A SHORTWAVE TROUGH BEGINS
TO AFFECT THE WESTERN PORTION BUT THE 700 MB TEMPERATURES ARE MUCH
WARMER. SATELLITE WOULD ALSO INDICATE ANOTHER INFLUX OF MID LEVEL
SUBTROPICAL MOISTURE FROM THE WEST. AND THE BIGGEST VARIABLE IS
WHERE WILL THERE BE LEFTOVER OUTFLOW BOUNDARIES. WOULD SAY THERE IS
A GOOD PROBABILITY OF ONE OR MORE IN THE CENTRAL AND EASTERN PORTION
OF THE AREA. SO TO ACCOUNT FOR THIS...PUT SLIGHT CHANCE IN THE WEST
AND LOW CHANCE IN THE EAST.
DEPENDING ON HOW PERSISTENT THE CONVECTION STAYS...HOW MUCH CLOUD
COVER HANGS AROUND...AND HOW SIGNIFICANT THE OUTFLOW IS...HIGH
TEMPERATURES MAY BE SEVERELY AFFECTED. BELIEVE THIS CONVECTION WILL
ALSO KEEP THE SYNOPTIC FRONT SUPPRESSED FURTHER TO THE SOUTH AND
WEST. KEPT THE COOLEST EAST AND THE WARMEST WEST BUT THAT IS HIGHLY
PROBLEMATIC AT THIS POINT.
FRIDAY/FRIDAY NIGHT...IN REGARDS TO THE PRECIPITATION...NEWEST MODEL
GUIDANCE SUPPORTS THE PREVIOUS FORECAST VERY WELL. RIDGE STARTS
BUILDING INTO THE AREA BUT THE MODELS DISAGREE ON HOW MUCH. MID
LEVEL TEMPERATURES WARM AND IT DOES LOOK LIKE MOST OF THE FORECAST
AREA EAST OF THE COLORADO BORDER DOES STAY CAPPED. A SURFACE TROUGH
SUPPLYING LOW LEVEL CONVERGENCE ALONG WITH A WEAK SHORTWAVE AFFECT
THE FAR WESTERN PORTION OF THE AREA WHICH IS WHERE THE 700 MB
TEMPERATURES ARE THE WARMEST. SO MADE LITTLE IF ANY CHANGE TO THE
PRECIPITATION FORECAST. NEW GUIDANCE SUPPORTS WARMING UP NOT ONLY
MAXES BUT THE MINS AS WELL. MOST OF THE AREA SHOULD BE ABOVE 100
DEGREES WITH THE EASTERN HALF THE HOTTEST FOR THE MAXES.
THIS COULD BE THE BEGINNING OF AN EXTENDED HEAT HIGHLIGHT FOR THE
EASTERN PORTION OF THE AREA. HEAT INDICES IN THE AFTERNOON REACH
105 IN THE EASTERN SIX COUNTIES DURING THE DAY. THEN OVERNIGHT MINS
DO NOT DROP OFF VERY MUCH AND I ACTUALLY MAY BE TOO COOL.
SATURDAY/SATURDAY NIGHT...SIMILAR SCENARIO FOR PRECIPITATION THESE
TWO PERIODS AS THE PREVIOUS TWO. THE MID/UPPER RIDGE LOOKS TO BUILD
IN MORE WITH HIGHER 700 MB TEMPERATURES AND ALSO LESS SURFACE
CONVERGENCE NEAR THE WESTERN END OF THE FORECAST AREA. WEAK LIFT IN
ADDITION TO THE EXTREME HEATING...COULD HELP SET OFF A FEW
THUNDERSTORMS. ALMOST CANNOT HELP BUT INITIATE THUNDERSTORMS IN
THIS KIND OF HEATING. CURRENT FORECAST HAD THIS SCENARIO WELL IN
HAND AND DID NOT CHANGE ANYTHING. MODELS LOOK TO INCREASE THE HEAT.
IT IS POSSIBLE I STILL DO NOT HAVE THE MAXES HOT ENOUGH...ESPECIALLY
IN THE EASTERN HALF. MINS LOOKS JUST AS WARM OR WARMER THAN THE
PREVIOUS NIGHT.
HEAT INDICES OF 105 PUSH ONE ROW OF COUNTIES FURTHER WEST THAN THE
PREVIOUS DAY. AM NOT ISSUING A HEAT HIGHLIGHT YET...BUT PLAN ON
MENTIONING THE FRIDAY INTO SATURDAY NIGHT PERIOD IN THE HWO.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 415 AM MDT THU JUL 11 2013
A LARGER THAN NORMAL DEGREE OF UNCERTAINTY IN THE EXTENDED
ON THE SYNOPTIC SCALE...THOUGH MOST SOLUTIONS END UP WITH SIMILAR
CONDITIONS FOR THE HIGH PLAINS. MAIN STORY EARLY NEXT WEEK WILL BE
HIGHS NEAR TO SLIGHTLY ABOVE NORMAL WITH GENERALLY DRY CONDITIONS.
ON SUNDAY A WEAK UPPER LEVEL DISTURBANCE MOVES ACROSS THE CENTRAL
ROCKIES AND INTO THE HIGH PLAINS...WHICH COULD HELP TO DEVELOP A FEW
SHOWERS/STORMS ON SUNDAY AFTERNOON INTO THE EVENING. TEMPS WILL BE
WARMEST ON SUNDAY WITH 850 TEMPS IN THE MID TO UPPER 20S...THOUGH
THE EC IS AN OUTLIER WITH SLIGHTLY COOLER TEMPS. THE REST OF THEE
WEEK MOST DETERMINISTIC GUIDANCE SHOWS AN UPPER LOW OVER MID-WEST
AND MOVING WEST AS IT WEAKENS...THOUGH AT THIS POINT BELIEVE THE
UPPER LOW WILL REMAIN FARTHER EAST AND AN UPPER RIDGE WILL BE OVER
HIGH PLAINS KEEPING THINGS DRY. 850 TEMPS FOR THE REST OF THE WEEK
WILL BE IN THE MID 20S IN THE AFTERNOON...WHICH WILL LEAD TO NEAR
NORMAL HIGHS. WHILE RAIN IS NOT ANTICIPATED THROUGH MOST OF THE WORK
WEEK...AT THIS POINT IT DOES NOT APPEAR FIRE WX WILL BE A CONCERN
NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1040 AM MDT THU JUL 11 2013
VFR CONDITIONS ARE EXPECTED AT KGLD AND KMCK FOR THE NEXT 24
HOURS. NO THUNDERSTORMS ARE EXPECTED AS VERY WARM MID LEVEL
TEMPERATURES AND SUBSIDENCE WILL INHIBIT THUNDERSTORMS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...BULLER
LONG TERM...JJM
AVIATION...FS
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
145 PM EDT THU JUL 11 2013
.UPDATE...
ISSUED AT 140 PM EDT THU JUL 11 2013
SOME STRAY CONVECTION LINGERS OVER SOUTHEASTERN KY WITH A BROKEN LINE
OF MAINLY JUST SHOWERS FROM PARTS OF SOUTHEAST OH INTO NORTH CENTRAL
KY. THERE HAS BEEN NO LIGHTNING WITH THIS SO FAR. HOWEVER...COVERAGE
OF THIS MAY INCREASE A LITTLE AS WE REACH PEAK HEATING COMBINED WITH
THE BOUNDARY SLOWLY SAGGING SOUTH ACROSS THE AREA. A FEW SLIGHT
ADJUSTMENTS WERE MADE BASED ON RADAR AND OBSERVATIONS...BUT NO MAJOR
CHANGES WERE NEEDED AT THIS TIME.
UPDATE ISSUED AT 1025 AM EDT THU JUL 11 2013
A COLD FRONT CONTINUES TO SAG SOUTH AND EAST ACROSS THE OH VALLEY
REGION AND EASTERN KY. THERE IS MAINLY LOW CLOUDS AND STRATUS LEFT
FROM EARLIER FOG AND RECENT RADAR IMAGERY SUGGESTS SOME SPRINKLES OR
LIGHT SHOWERS AND SOME DRIZZLE WITH THIS ATTM. RECENT 12Z NAM
GUIDANCE AS WELL AS THE 9Z SREF SUGGEST THE POTENTIAL FOR SOME MAINLY
AFTERNOON CONVECTION IN THE SOUTHEAST CWA. THE HRRR HAS SOME
CONVECTIVE ACTIVITY AS WELL...BUT SEEMS TO HAVE IT TOO FAR TO THE
NORTHWEST.
OVERALL...PERSISTENCE AND RECENT MODEL GUIDANCE SUGGESTS THAT
ISOLATED TO SCATTERED SHRA/TSRA ARE POSSIBLE DURING PEAK HEATING
TODAY AS THE BOUNDARY SLOWLY SAGS SOUTHEAST TOWARD THE VA BORDER.
OTHER THAN FRESHENING UP THE FORECAST BASED ON RECENT OBSERVATIONS...
NO SIGNIFICANT CHANGES WERE MADE.
UPDATE ISSUED AT 737 AM EDT THU JUL 11 2013
BASED ON AMOUNT OF FOG ACROSS MUCH OF THE AREA...UPDATED TO INCLUDE
DENSE FOG WORDING IN THE GRIDS. WITH LLVL INVERSION AND FOG STILL IN
PLACE...THERE HAS BEEN NO CONVECTIVE DEVELOPMENT SO FAR THIS MORNING.
SOME ISL/SCT SHOWERS ARE STILL POSSIBLE AS THE FRONT PASSES THROUGH
LATE THIS MORNING/EARLY THIS AFTERNOON...BUT SO LONG AS FOG AND
INVERSION ARE IN PLACE...POPS WILL BE LIMITED. WENT AHEAD AND BUMPED
DOWN POPS SLIGHTLY TO TAKE OUT ONGOING SCT WORDING THIS
MORNING...WITH BETTER CHANCES MOVING IN FROM PIKE TO MCCREARY COUNTY
OVER THE NEXT FEW HOURS HOPEFULLY AS FOG AND INVERSION BEGIN TO LIFT.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 340 AM EDT THU JUL 11 2013
AFTER A VERY EVENTFUL WEEK...IT SEEMS AS THOUGH QUIETER AND NICER
WEATHER IS FINALLY IN STORE. COLD FRONT WILL CONTINUE TO PUSH
THROUGH SE KY THIS MORNING...BUT MAIN AREA OF CONVECTION AHEAD OF
THE FRONT HAS MOVED OUT OF THE REGION WITH AN ABUNDANT AMOUNT OF
DRY AIR NOW FILTERING IN. A FEW ISOLATED SHALLOW AND SHORT LIVED
SHOWERS COULD BE POSSIBLE AS THE FRONT PASSES THROUGH IN THE LATE
MORNING/EARLY AFTERNOON...BUT LITTLE IS EXPECTED FOR IMPACTS. BACKED
OFF ON POPS BOTH FOR THE OVERNIGHT LAST NIGHT AND INTO THE DAY TODAY
AS A RESULT. MAIN CONCERN RIGHT NOW IS THE FACT THAT DESPITE ALL OF
THIS DRY AIR IN PLACE...RAIN THAT TRAVERSED THE REGION YESTERDAY HAS
LED TO VERY MOIST LLVLS TRAPPED BELOW A NEAR SURFACE INVERSION. AS A
RESULT...FAIRLY DENSE AND WIDESPREAD FOG STARTED FORMING LAST
NIGHT...AND WILL CONTINUE THROUGHOUT THE MORNING HOURS BEFORE SURFACE
INVERSION CLIMBS A LITTLE HIGHER UP IN THE ATMOSPHERE. AT THIS
POINT...FOG WILL LIFT INTO A LLVL STRATUS DECK AND
THEN EVENTUALLY A BROKEN CU DECK BEFORE IT SCATTERS OFF IN THE
EVENING. IT IS ALSO IN THIS LAYER THAT WE WILL SEE OUR BEST
POTENTIAL FOR ANY ABOVE MENTIONED LIGHT CONVECTIVE DEVELOPMENT. IN
GOOD NEWS...THIS DECK WILL BE FAIRLY SHALLOW WITH THE POTENTIAL TO
BREAK DOWN EVEN SOONER VIA ANY DAYTIME MODIFICATION TO THE SOUNDING.
OTHERWISE...PLAN ON GREAT WEATHER TODAY. HIGH TEMPERATURES WILL
BE BELOW NORMAL ACROSS THE REGION...REACHING NEAR 80 IN MOST
LOCATIONS WITH WINDS COMING FROM A NRLY DIRECTION. AND WITH A DRIER
CONTINENTAL AIRMASS IN PLACE...EXPECT HUMIDITY LEVELS TO BE MUCH
LOWER THAN PREVIOUS DAYS. THE SAME WILL CARRY OVER INTO THE
OVERNIGHT HOURS AND INTO THE DAY TOMORROW. SOME PATCHY FOG WILL BE
POSSIBLE OVERNIGHT TONIGHT...BUT SHOULD MAINLY BE LIGHT AND CONFINED
TO THE EXTREME VALLEYS WHERE INVERSION IS MORE LIKELY TO SET UP. DRY
AIRMASS WILL PREVENT A REPEAT FROM LAST NIGHT/THIS MORNING.
OTHERWISE...ENJOY. HIGH PRESSURE AND DRY/MILD WEATHER SHOULD CARRY
OVER INTO THE WEEKEND.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 340 AM EDT THU JUL 11 2013
THERE IS STILL GOOD AGREEMENT IN THE MODELS EARLY ON...BUT NOT FAR
INTO THE PERIOD THEIR SOLUTIONS BEGIN TO DIVERGE. THE ELEMENT IN
DISPUTE IS AN UPPER LOW WHICH WILL BE LEFT BEHIND BY THE TROUGH
CURRENTLY DROPPING INTO THE EASTERN CONUS. MODELS DO AGREE ON A
CLOSED LOW BEING PINCHED OFF NEAR THE WV/MD BORDER BY FRIDAY
EVENING. THIS LOW THEN RETROGRADES...BUT EXACTLY WHERE IT GOES AND
HOW FAST IT MOVES ARE IN QUESTION. WITHOUT A CLEAR PREFERENCE...WILL
USE A BLENDED MODEL SOLUTION.
AT THE SURFACE...OUR INITIAL AIR MASS WILL BE DRY...HAVING BEEN
SUPPLIED BY HIGH PRESSURE OVER THE GREAT LAKES. THIS HIGH WILL
WEAKEN AND SUBTROPICAL HIGH PRESSURE OVER THE ATLANTIC WILL BECOME
MORE DOMINANT. IT WILL SEND A MORE HUMID AIR MASS BACK NORTHWEST
OVER THE LOCAL AREA...UNDERNEATH THE WEAK TROUGH OR UPPER LOW LEFT
BEHIND. THIS WILL RESULT IN A POSSIBILITY OF SHOWERS/THUNDERSTORMS
BY LATE SATURDAY NIGHT OR SUNDAY. THE BEST CHANCE WILL BE MONDAY AND
TUESDAY. BY WEDNESDAY...MODELS SHOW WHAT IS LEFT OF THE UPPER LOW TO
BE WELL TO OUR WEST OR SOUTHWEST...WITH UPPER LEVEL RIDGING BUILDING
OVER THE OHIO VALLEY...CUTTING INTO POPS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 140 PM EDT THU JUL 11 2013
WITH STRONG JULY SUNSHINE AND A BOUNDARY DROPPING SOUTHEAST ACROSS
THE REGION...EARLIER STRATUS HAS LIFTED INTO CU. A FEW ISOLATED
SHOWERS HAVE DEVELOPED CLOSER TO THE OH RIVER. COVERAGE OF THESE
SHOULD INCREASE THROUGH 20Z. THE CONVECTION SHOULD BEGIN TO WANE BY
0Z WITH THE CU MIXING OUT AS THE BOUNDARY MOVES FURTHER SOUTH AND
DAYTIME HEATING IS LOST. BEHIND THE BOUNDARY...A DRIER AIRMASS WILL
BE MOVING INTO THE REGION...BUT DRYING WILL BE SLOWER NEARER TO THE
VA AND TN BORDERS. LAMP GUIDANCE IS HITTING THE FOG RATHER HARD BUT
MOS GUIDANCE IS NOT QUITE AS PESSIMISTIC. WITH THIS ISSUANCE...OPTED TO
INSERT FOG INTO THE TAFS AT LOZ AND SME WHERE FOG COULD REDUCE VIS
BELOW AIRPORT MINS BETWEEN 8Z AND ABOUT 13Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...JMW
LONG TERM...HAL
AVIATION...JP
AREA FORECAST DISCUSSION
NWS GLASGOW MT
209 PM MDT THU JUL 11 2013
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH SATURDAY...
MAIN CONCERN WILL BE CONVECTION INITIATION HEADING INTO THIS
AFTERNOON AND EVENING. CURRENT VISIBLE SATELLITE IMAGERY IS
INDICATING A HUGE MASS OF CLOUDINESS OVERSPREADING THE CWA FROM
SOUTHWEST TO NORTHEAST...WITH MORE IN THE WAY OF SUNSHINE ACROSS
THE SOUTHEAST. THE SOUTHEASTERN PORTIONS OF THE CWA THEREFORE WILL
BE MUCH MORE UNSTABLE THIS AFTERNOON AND EVENING AND THIS IS WHERE
HIGHER CAPE AND MORE FAVORABLE LIFTED INDEX VALUES ARE PRESENT.
STORM SCALE ENSEMBLE OF OPPORTUNITY...HRRR...AND NAM SOLUTIONS DO
CAPTURE THIS WELL AND THUS THERE IS HIGHER CONFIDENCE IN ISOLATED
TO SCATTERED THUNDERSTORMS IN THIS AREA. PRAIRIE...DAWSON...WIBAUX...AND
POSSIBLY AS FAR NORTH AS RICHLAND COUNTIES APPEAR TO HAVE THE BEST
POTENTIAL FOR A FEW STORMS TO BECOME SEVERE AS THEY TRAVERSE
THROUGH. LATEST NAM BUFKIT SOUNDINGS CONTINUE TO NICELY DEPICT
INVERTED-V SIGNATURE AND SO STRONG WINDS WILL BE THE PRIMARY
CONCERNS WITH ANY STORMS. AS UPPER LEVEL WAVE AND FRONT PUSHES
FURTHER EAST AND MEETS UP WITH THIS UNSTABLE ENVIRONMENT...STORMS
SHOULD INITIATE. IN FACT...ALREADY SEEING THE FIRST SIGNS OF
CONVECTION JUST SOUTH OF THE CWA IN VISIBLE SATELLITE IMAGERY.
THE 11/12Z MODEL GUIDANCE SHOWS A BIT OF DISCREPANCY IN TERMS OF
THIS EVENING INTO TONIGHT. WHILE ANY CONVECTION THAT PUSHES
THROUGH THE SOUTHEAST SHOULD BE DONE WITH BY EVENING...THE LATEST
HRRR IS SHOWING SOME SHOWER ACTIVITY OVERSPREADING THE ENTIRE CWA
OVERNIGHT FROM SOUTHWEST TO NORTHEAST. THE NAM/GFS/ECMWF ARE NOT
AS BULLISH ON THIS...BUT GIVEN THE AREAL EXTENT OF CLOUDINESS
MOVING INTO THE FORECAST REGION AND SHOWERS SHOWING UP ON RADAR
THAT ARE MOVING IN...DID LEAN ON THE HRRR FOR NOW...BUT POPS STILL
MAY PROVE TO BE SOMEWHAT CONSERVATIVE. AT ANY RATE...ANOTHER
SHORTWAVE WILL MOVE ACROSS THE INTERNATIONAL BORDER FRIDAY INTO
SATURDAY WHICH SHOULD MAINTAIN CHANCES FOR SHOWERS AND
THUNDERSTORMS. BEHIND THIS EVENING/S FRONTAL PASSAGE THOUGH
TEMPERATURES SHOULD BE MORE SEASONABLE. WILL NEED TO MONITOR FOR
POSSIBLE SEVERE AGAIN ON SATURDAY...DOES LOOK LIKE THE BEST
FORCING WILL BE ACROSS SASKATCHEWAN CLOSER TO THE TRACK OF THE
WAVE. MALIAWCO
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY...
MOST OF THE LONG TERM FORECAST PERIOD IS CHARACTERIZED BY A
PERSISTENT SOUTHWESTERLY FLOW ALOFT WITH MULTIPLE EMBEDDED SHORT
WAVE DISTURBANCES THROUGHOUT.
MODES ARE HINTING THAT A SLIGHT RIDGING INFLUENCE MAY PUSH INTO
THE NORTHERN HIGH PLAINS TUESDAY AND BEYOND.
THERE ARE ENOUGH MODEL DISCREPANCIES TO RATE THE FORECAST
CONFIDENCE ABOUT AVERAGE OR SLIGHTLY BELOW AVERAGE. HAVE THEREFORE
CHOSEN A BLEND AND BROAD-BRUSH APPROACH FOR NOW. MADE ONLY SLIGHT
ADJUSTMENTS TO THE GOING FORECAST. EXPECT THE COOLEST DAY TO BE
TUESDAY AND THE WARMEST DAY TO BE THURSDAY WITH OFF AND ON
CHANCES FOR SHOWERS AND THUNDERSTORMS. BMICKELSON
PREVIOUS LONG TERM DISCUSSION...SYNOPTIC SET UP... LONG TERM
BEGINS WITH A LARGE HEAT DOME STRETCHED OVER THE CENTRAL AND
SOUTHERN US PLAINS AND FOUR CORNERS REGION. A CLOSED LOW EXISTS
OVER THE NORTHWEST TERRITORIES WITH A TROUGH JUTTING OFF OVER
NORTHERN ALBERTA AND BRITISH COLUMBIA. NORTHEAST MONTANA LIES IN
BETWEEN THESE TWO FEATURES OF FLUCTUATING ZONAL ALOFT ALL THE WAY
BACK TO OFF THE COAST OF THE PACIFIC NORTHWEST.
SATURDAY NIGHT THROUGH MONDAY... FLOW WILL TILT SLIGHTLY SOUTHWEST
AND ALLOW A FEW SHORTWAVES TO PASS THROUGH NORTHEAST MONTANA ALONG
WITH PACIFIC MOISTURE. TIMING OF ANY PARTICULAR WAVE IS DIFFICULT
AND WASHED OUT. HOWEVER... THE EASTERN HALF OF THE CWA APPEARS TO
HAVE HIGHER CHANCES FOR POPS AS MOISTURE IS EXPECTED TO INCREASE
TO THE EAST NEAR THE SURFACE.
MONDAY NIGHT THROUGH WEDNESDAY... THE HEAT DOME OVER THE WESTERN
HALF OF THE US WILL EXTEND A RIDGE UP THROUGH THE THE PACIFIC
NORTHWEST AND BRITISH COLUMBIA. THE RIDGE IS WEAK... SO SHORTWAVES
COULD STILL BREAK THROUGH... BUT IT IS ANTICIPATED TO SUBTLY TILT
FLOW TO THE NORTHWEST WITH DRIER MID LEVELS. A SEMI-PERMANENT LEE
SURFACE TROUGH WILL SET UP DURING THESE PERIODS AND BE A FOCAL
POINT FOR ANY AFTERNOON STORM DEVELOPMENT. TIMING OF WAVES DURING
THIS PERIOD IS RATHER DIFFICULT HOWEVER. EXPECT A WARMING TREND AS
THE RIDGE BUILDS TO THE WEST AND INCREASES INFLUENCE.
WEDNESDAY NIGHT ONWARD... MODELS ARE HINTING AT A TROUGH DROPPING
SOUTH OF THE GULF OF ALASKA TO OFF THE COAST OF THE PACIFIC
NORTHWEST. THIS WILL NUDGE THE BUILDING HEAT DOME OVER THE
INTER-MOUNTAIN WEST EAST... INCREASING THE INFLUENCE OVER NORTHEAST
MONTANA AND TRENDING WARMER AND DRIER WEATHER OVERALL. GAH
&&
.AVIATION...
FLIGHT CATEGORY:
MOSTLY VFR WITH LOWER CONDITIONS POSSIBLE FOR KSDY AND KGDV.
AMENDMENTS MAY BE NEEDED THERE FOR THUNDERSTORMS LATER TODAY.
IMPACTS:
SHOWERS AND THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND
EVENING...ESPECIALLY AT KSDY AND KGDV. TEMPORARY REDUCTIONS IN
FLIGHT CONDITIONS CAN BE EXPECTED. THESE TERMINALS SHOULD BE
AWARE OF STRONG VERTICAL WIND SHEAR DURING THE AFTERNOON AND
EVENING HOURS WHICH COULD COMPLICATE GROUND OPERATIONS. THIS MAY
RESULT IN STRONG OR GUSTY WINDS...ESPECIALLY IN OR NEAR
THUNDERSTORMS. BRIEF FUEL LOADING CONDITIONS ARE POSSIBLE WITH
STORMS.
AREA WINDS:
SOUTHWEST WINDS 10 TO 20 KTS SUSTAINED WITH POSSIBLE GUSTS NEAR
30KTS FOR KSDY AND KGDV CONTINUING THROUGH THIS AFTERNOON. WINDS
WILL VEER TO THE WEST AND NORTHWEST BEHIND A COLD FRONT LATER THIS
AFTERNOON AND EVENING.
MICKELSON
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW