Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/12/13
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
1137 AM CDT WED JUL 10 2013
.UPDATE...
THE COLD FRONT CONTINUES TO MOVE THROUGH SOUTHERN MISSOURI LATE
THIS MORNING. A FEW LIGHT SHOWERS HAVE BEEN NOTED IN NORTHEAST
SECTIONS. WILL KEEP THE CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS
THE AREA THIS AFTERNOON WITH BEST CHANCES CENTRAL AND SOUTH.
INCREASED MAXIMUM TEMPERATURES A COUPLE OF DEGREES BASED ON OBS
AND TRENDS. QUITE A BIT OF CLOUD COVER IS OVER THE NORTH FROM THE
THUNDERSTORMS IN MISSOURI.
&&
.PREV DISCUSSION... /ISSUED 637 AM CDT WED JUL 10 2013/
AVIATION...
PREVALENT VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD.
CONVECTION IN SOUTHERN MISSOURI CONTINUES TO SLOWLY MOVE SOUTH
AHEAD OF A FRONTAL BOUNDARY. THIS WILL DIMINISH SOMEWHAT IN THE
NEXT FEW HOURS... BUT ADDITIONAL DEVELOPMENT WILL BE POSSIBLE
LATER THIS MORNING AND INTO THE AFTERNOON HOURS. AT THIS
POINT...HAVE CONTINUED TO MENTION VCTS IN THE NORTHERN SITES...BUT
AS FOR THE CENTRAL AND SOUTH... NOT TOO CONFIDENT YET IF PRECIP
WILL BE SEEN AT ALL...GIVEN THE EXPECTED SCATTERED NATURE OF THE
PRECIP LATER TODAY. TAFS ALREADY OUT.
PREV DISCUSSION... /ISSUED 331 AM CDT WED JUL 10 2013/
SHORT TERM...TODAY THROUGH SATURDAY NIGHT
CONVECTION WAS ONGOING ACROSS PARTS OF SOUTHERN/CENTRAL MISSOURI
EARLY THIS MORNING. FURTHER NORTH A FRONTAL BOUNDARY STRETCHED
ACROSS NORTHERN KANSAS AND UP INTO SOUTHEASTERN IOWA. THE FORECAST
TODAY IS SOMEWHAT TRICKY AS A RESULT OF THESE TWO FEATURES. THE
ONGOING CONVECTION HAS SENT OUT SOME OUTFLOW BOUNDARIES THAT
SHOULD WORK INTO NRN ARKANSAS BY MID MORNING. THE 4KM WRF AND ALSO
THE RAPID REFRESH RUC SUGGEST THESE BOUNDARIES WILL LIKELY BE A
FOCUS FOR MIDDAY AND AFTERNOON SHOWER AND THUNDERSTORM ACTIVITY
SOUTH OF THE I-40 CORRIDOR. HOWEVER THE FRONTAL BOUNDARY WILL MOVE
IN DURING THE EVENING HOURS...UPON WHICH THE MORE COARSE MODELS
SUGGEST WILL BE MORE DOMINANT SHOWER/THUNDERSTORM ACTIVITY.
TRENDED THE FORECAST IN THE DIRECTION OF THE FORMER...WITH
SLIGHTLY COOLER /WE ARE TALKING ABOUT 1-2 DEGREES HERE/ AFTERNOON
HIGHS UP NORTH THAN GUIDANCE SUGGESTS...AND PLAYED RAIN CHANCES
TOWARDS THE SOUTHERN ISOLD TO SCT VARIETY INSTEAD OF CONVECTION
BEING TIED TO THE FRONT. THAT SAID...DID LEAVE SLIGHT CHANCES IN
THE NORTH THROUGH THE DAY AND INTO TONIGHT TO ACCOUNT FOR
CONVECTION ALONG THE FRONT.
OTHERWISE...NOT MUCH TO TALK ABOUT IN THE EXTENDED. THE
AFOREMENTIONED FRONT WILL PUSH WELL INTO THE STATE BY THURSDAY.
UPPER LEVEL HIGH PRESSURE SITUATED OVER THE PLAINS WILL BECOME
HIGHLY AMPLIFIED BY LATE THURSDAY. LEFT SOME SLIGHT RAIN CHANCES
OVER THE FAR SOUTH AND FAR SOUTHWEST PARTS OF THE FORECAST AREA THU
AND FRI AFTERNOONS. THERE IS SOME QPF SIGNAL IN NUMERICAL MODELS
BOTH DAYS IN THOSE REGIONS...WHICH SEEMS REASONABLE. TEMPERATURES
WILL NOT COOL DOWN MUCH IN THE SOUTHWEST...BUT HIGHS IN THE
NORTHEAST BY FRIDAY WILL LIKELY NOT REACH 90 DEGREES. HOWEVER DRIER
AIR WILL FILTER IN ACROSS ARKANSAS SO EVEN WITH HIGHS IN THE LOW 90S
ACROSS THE SOUTHWEST HALF OF THE STATE...THERE WILL BE SOME RELIEF
FROM THE HOT AND MUGGY CONDITIONS HEADING INTO THE WEEKEND.
LONG TERM...SATURDAY NIGHT THROUGH TUESDAY
THE LONG TERM OFFERS AN ODD SYNOPTIC SETUP FOR JULY. AT THE
BEGINNING...THE RETROGRADING CUTOFF LOW WILL BE MOVING INTO COASTAL
TEXAS...WITH AN ELONGATED UPPER RIDGE SETTING UP OVER THE PLAINS.
THE AFOREMENTIONED LOW WILL BRING MOISTURE UP INTO THE REGION...AND
WITH IT A CHANCE OF SHOWERS/STORMS EACH DAY...WHICH SHOULD MOSTLY BE
DIURNALLY DRIVEN.
WILL CONTINUE TO KEEP RAIN CHANCES SMALL TO ACCOUNT FOR
UNCERTAINTIES WITH THIS SETUP.
IF YOU CAN BELIEVE YOUR EYES...THE EXACT SAME THING LOOKS TO HAPPEN
BY LATE MONDAY INTO TUESDAY...AS THE MODELS ADVERTISE ANOTHER CUTOFF
UPPER LOW FORMING AND RETROGRADING TOWARD THE MID SOUTH REGION. THIS
WILL BRING A REINFORCING SHOT OF AT LEAST SMALL RAIN CHANCES TO END
THE PERIOD.
INITIALLY...TEMPERATURES WILL BE A LITTLE BELOW SEASONAL AVERAGES
DUE TO EASTERLY SURFACE FLOW. BY MONDAY AND TUESDAY...TEMPERATURES
WILL BE A BIT WARMER...BUT WILL BE KEPT IN CHECK BY CLOUD COVER
ASSOCIATED WITH THE UPPER LOWS.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 96 74 90 67 / 20 20 10 10
CAMDEN AR 97 76 95 72 / 30 30 20 20
HARRISON AR 96 73 90 66 / 20 20 10 10
HOT SPRINGS AR 98 77 95 72 / 30 30 20 10
LITTLE ROCK AR 98 77 95 70 / 30 30 20 10
MONTICELLO AR 96 76 94 72 / 30 30 20 10
MOUNT IDA AR 97 77 94 71 / 30 30 20 10
MOUNTAIN HOME AR 97 72 90 66 / 20 20 10 10
NEWPORT AR 96 74 90 67 / 20 20 10 10
PINE BLUFF AR 97 76 94 70 / 30 30 20 10
RUSSELLVILLE AR 97 76 95 71 / 30 20 20 10
SEARCY AR 97 75 92 68 / 30 20 10 10
STUTTGART AR 97 76 93 69 / 30 30 20 10
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
51
AREA FORECAST DISCUSSION...UPDATED
NWS LITTLE ROCK AR
637 AM CDT WED JUL 10 2013
.AVIATION...
PREVALENT VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD.
CONVECTION IN SOUTHERN MISSOURI CONTINUES TO SLOWLY MOVE SOUTH
AHEAD OF A FRONTAL BOUNDARY. THIS WILL DIMINISH SOMEWHAT IN THE
NEXT FEW HOURS... BUT ADDITIONAL DEVELOPMENT WILL BE POSSIBLE
LATER THIS MORNING AND INTO THE AFTERNOON HOURS. AT THIS
POINT...HAVE CONTINUED TO MENTION VCTS IN THE NORTHERN SITES...BUT
AS FOR THE CENTRAL AND SOUTH... NOT TOO CONFIDENT YET IF PRECIP
WILL BE SEEN AT ALL...GIVEN THE EXPECTED SCATTERED NATURE OF THE
PRECIP LATER TODAY. TAFS ALREADY OUT.
&&
.PREV DISCUSSION... /ISSUED 331 AM CDT WED JUL 10 2013/
SHORT TERM...TODAY THROUGH SATURDAY NIGHT
CONVECTION WAS ONGOING ACROSS PARTS OF SOUTHERN/CENTRAL MISSOURI
EARLY THIS MORNING. FURTHER NORTH A FRONTAL BOUNDARY STRETCHED
ACROSS NORTHERN KANSAS AND UP INTO SOUTHEASTERN IOWA. THE FORECAST
TODAY IS SOMEWHAT TRICKY AS A RESULT OF THESE TWO FEATURES. THE
ONGOING CONVECTION HAS SENT OUT SOME OUTFLOW BOUNDARIES THAT
SHOULD WORK INTO NRN ARKANSAS BY MID MORNING. THE 4KM WRF AND ALSO
THE RAPID REFRESH RUC SUGGEST THESE BOUNDARIES WILL LIKELY BE A
FOCUS FOR MIDDAY AND AFTERNOON SHOWER AND THUNDERSTORM ACTIVITY
SOUTH OF THE I-40 CORRIDOR. HOWEVER THE FRONTAL BOUNDARY WILL MOVE
IN DURING THE EVENING HOURS...UPON WHICH THE MORE COARSE MODELS
SUGGEST WILL BE MORE DOMINANT SHOWER/THUNDERSTORM ACTIVITY.
TRENDED THE FORECAST IN THE DIRECTION OF THE FORMER...WITH
SLIGHTLY COOLER /WE ARE TALKING ABOUT 1-2 DEGREES HERE/ AFTERNOON
HIGHS UP NORTH THAN GUIDANCE SUGGESTS...AND PLAYED RAIN CHANCES
TOWARDS THE SOUTHERN ISOLD TO SCT VARIETY INSTEAD OF CONVECTION
BEING TIED TO THE FRONT. THAT SAID...DID LEAVE SLIGHT CHANCES IN
THE NORTH THROUGH THE DAY AND INTO TONIGHT TO ACCOUNT FOR
CONVECTION ALONG THE FRONT.
OTHERWISE...NOT MUCH TO TALK ABOUT IN THE EXTENDED. THE
AFOREMENTIONED FRONT WILL PUSH WELL INTO THE STATE BY THURSDAY.
UPPER LEVEL HIGH PRESSURE SITUATED OVER THE PLAINS WILL BECOME
HIGHLY AMPLIFIED BY LATE THURSDAY. LEFT SOME SLIGHT RAIN CHANCES
OVER THE FAR SOUTH AND FAR SOUTHWEST PARTS OF THE FORECAST AREA THU
AND FRI AFTERNOONS. THERE IS SOME QPF SIGNAL IN NUMERICAL MODELS
BOTH DAYS IN THOSE REGIONS...WHICH SEEMS REASONABLE. TEMPERATURES
WILL NOT COOL DOWN MUCH IN THE SOUTHWEST...BUT HIGHS IN THE
NORTHEAST BY FRIDAY WILL LIKELY NOT REACH 90 DEGREES. HOWEVER DRIER
AIR WILL FILTER IN ACROSS ARKANSAS SO EVEN WITH HIGHS IN THE LOW 90S
ACROSS THE SOUTHWEST HALF OF THE STATE...THERE WILL BE SOME RELIEF
FROM THE HOT AND MUGGY CONDITIONS HEADING INTO THE WEEKEND.
LONG TERM...SATURDAY NIGHT THROUGH TUESDAY
THE LONG TERM OFFERS AN ODD SYNOPTIC SETUP FOR JULY. AT THE
BEGINNING...THE RETROGRADING CUTOFF LOW WILL BE MOVING INTO COASTAL
TEXAS...WITH AN ELONGATED UPPER RIDGE SETTING UP OVER THE PLAINS.
THE AFOREMENTIONED LOW WILL BRING MOISTURE UP INTO THE REGION...AND
WITH IT A CHANCE OF SHOWERS/STORMS EACH DAY...WHICH SHOULD MOSTLY BE
DIURNALLY DRIVEN.
WILL CONTINUE TO KEEP RAIN CHANCES SMALL TO ACCOUNT FOR
UNCERTAINTIES WITH THIS SETUP.
IF YOU CAN BELIEVE YOUR EYES...THE EXACT SAME THING LOOKS TO HAPPEN
BY LATE MONDAY INTO TUESDAY...AS THE MODELS ADVERTISE ANOTHER CUTOFF
UPPER LOW FORMING AND RETROGRADING TOWARD THE MID SOUTH REGION. THIS
WILL BRING A REINFORCING SHOT OF AT LEAST SMALL RAIN CHANCES TO END
THE PERIOD.
INITIALLY...TEMPERATURES WILL BE A LITTLE BELOW SEASONAL AVERAGES
DUE TO EASTERLY SURFACE FLOW. BY MONDAY AND TUESDAY...TEMPERATURES
WILL BE A BIT WARMER...BUT WILL BE KEPT IN CHECK BY CLOUD COVER
ASSOCIATED WITH THE UPPER LOWS.
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AVIATION...57
AREA FORECAST DISCUSSION...CORRECTED
NWS LITTLE ROCK AR
331 AM CDT WED JUL 10 2013
.SHORT TERM...TODAY THROUGH SATURDAY NIGHT
CONVECTION WAS ONGOING ACROSS PARTS OF SOUTHERN/CENTRAL MISSOURI
EARLY THIS MORNING. FURTHER NORTH A FRONTAL BOUNDARY STRETCHED
ACROSS NORTHERN KANSAS AND UP INTO SOUTHEASTERN IOWA. THE FORECAST
TODAY IS SOMEWHAT TRICKY AS A RESULT OF THESE TWO FEATURES. THE
ONGOING CONVECTION HAS SENT OUT SOME OUTFLOW BOUNDARIES THAT
SHOULD WORK INTO NRN ARKANSAS BY MID MORNING. THE 4KM WRF AND ALSO
THE RAPID REFRESH RUC SUGGEST THESE BOUNDARIES WILL LIKELY BE A
FOCUS FOR MIDDAY AND AFTERNOON SHOWER AND THUNDERSTORM ACTIVITY
SOUTH OF THE I-40 CORRIDOR. HOWEVER THE FRONTAL BOUNDARY WILL MOVE
IN DURING THE EVENING HOURS...UPON WHICH THE MORE COARSE MODELS
SUGGEST WILL BE MORE DOMINANT SHOWER/THUNDERSTORM ACTIVITY.
TRENDED THE FORECAST IN THE DIRECTION OF THE FORMER...WITH
SLIGHTLY COOLER /WE ARE TALKING ABOUT 1-2 DEGREES HERE/ AFTERNOON
HIGHS UP NORTH THAN GUIDANCE SUGGESTS...AND PLAYED RAIN CHANCES
TOWARDS THE SOUTHERN ISOLD TO SCT VARIETY INSTEAD OF CONVECTION
BEING TIED TO THE FRONT. THAT SAID...DID LEAVE SLIGHT CHANCES IN
THE NORTH THROUGH THE DAY AND INTO TONIGHT TO ACCOUNT FOR
CONVECTION ALONG THE FRONT.
OTHERWISE...NOT MUCH TO TALK ABOUT IN THE EXTENDED. THE
AFOREMENTIONED FRONT WILL PUSH WELL INTO THE STATE BY THURSDAY.
UPPER LEVEL HIGH PRESSURE SITUATED OVER THE PLAINS WILL BECOME
HIGHLY AMPLIFIED BY LATE THURSDAY. LEFT SOME SLIGHT RAIN CHANCES
OVER THE FAR SOUTH AND FAR SOUTHWEST PARTS OF THE FORECAST AREA THU
AND FRI AFTERNOONS. THERE IS SOME QPF SIGNAL IN NUMERICAL MODELS
BOTH DAYS IN THOSE REGIONS...WHICH SEEMS REASONABLE. TEMPERATURES
WILL NOT COOL DOWN MUCH IN THE SOUTHWEST...BUT HIGHS IN THE
NORTHEAST BY FRIDAY WILL LIKELY NOT REACH 90 DEGREES. HOWEVER DRIER
AIR WILL FILTER IN ACROSS ARKANSAS SO EVEN WITH HIGHS IN THE LOW 90S
ACROSS THE SOUTHWEST HALF OF THE STATE...THERE WILL BE SOME RELIEF
FROM THE HOT AND MUGGY CONDITIONS HEADING INTO THE WEEKEND.
&&
.LONG TERM...SATURDAY NIGHT THROUGH TUESDAY
THE LONG TERM OFFERS AN ODD SYNOPTIC SETUP FOR JULY. AT THE
BEGINNING...THE RETROGRADING CUTOFF LOW WILL BE MOVING INTO COASTAL
TEXAS...WITH AN ELONGATED UPPER RIDGE SETTING UP OVER THE PLAINS.
THE AFOREMENTIONED LOW WILL BRING MOISTURE UP INTO THE REGION...AND
WITH IT A CHANCE OF SHOWERS/STORMS EACH DAY...WHICH SHOULD MOSTLY BE
DIURNALLY DRIVEN.
WILL CONTINUE TO KEEP RAIN CHANCES SMALL TO ACCOUNT FOR
UNCERTAINTIES WITH THIS SETUP.
IF YOU CAN BELIEVE YOUR EYES...THE EXACT SAME THING LOOKS TO HAPPEN
BY LATE MONDAY INTO TUESDAY...AS THE MODELS ADVERTISE ANOTHER CUTOFF
UPPER LOW FORMING AND RETROGRADING TOWARD THE MID SOUTH REGION. THIS
WILL BRING A REINFORCING SHOT OF AT LEAST SMALL RAIN CHANCES TO END
THE PERIOD.
INITIALLY...TEMPERATURES WILL BE A LITTLE BELOW SEASONAL AVERAGES
DUE TO EASTERLY SURFACE FLOW. BY MONDAY AND TUESDAY...TEMPERATURES
WILL BE A BIT WARMER...BUT WILL BE KEPT IN CHECK BY CLOUD COVER
ASSOCIATED WITH THE UPPER LOWS.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 97 73 90 67 / 20 20 10 10
CAMDEN AR 96 74 95 72 / 30 30 20 20
HARRISON AR 94 72 90 66 / 20 20 10 10
HOT SPRINGS AR 97 75 95 72 / 30 30 20 10
LITTLE ROCK AR 96 75 95 70 / 30 30 20 10
MONTICELLO AR 95 75 94 72 / 30 30 20 10
MOUNT IDA AR 96 75 94 71 / 30 30 20 10
MOUNTAIN HOME AR 96 71 90 66 / 20 20 10 10
NEWPORT AR 96 73 90 67 / 20 20 10 10
PINE BLUFF AR 94 75 94 70 / 30 30 20 10
RUSSELLVILLE AR 98 75 95 71 / 30 20 20 10
SEARCY AR 96 74 92 68 / 30 20 10 10
STUTTGART AR 97 74 93 69 / 30 30 20 10
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...64 / LONG TERM...57
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
330 AM CDT WED JUL 10 2013
.SHORT TERM...TODAY THROUGH SATURDAY NIGHT
CONVECTION WAS ONGOING ACROSS PARTS OF SOUTHERN/CENTRAL MISSOURI
EARLY THIS MORNING. FURTHER NORTH A FRONTAL BOUNDARY STRETCHED
ACROSS NORTHERN KANSAS AND UP INTO SOUTHEASTERN IOWA. THE FORECAST
TODAY IS SOMEWHAT TRICKY AS A RESULT OF THESE TWO FEATURES. THE
ONGOING CONVECTION HAS SENT OUT SOME OUTFLOW BOUNDARIES THAT
SHOULD WORK INTO NRN ARKANSAS BY MID MORNING. THE 4KM WRF AND ALSO
THE RAPID REFRESH RUC SUGGEST THESE BOUNDARIES WILL LIKELY BE A
FOCUS FOR MIDDAY AND AFTERNOON SHOWER AND THUNDERSTORM ACTIVITY
SOUTH OF THE I-40 CORRIDOR. HOWEVER THE FRONTAL BOUNDARY WILL MOVE
IN DURING THE EVENING HOURS...UPON WHICH THE MORE COARSE MODELS
SUGGEST WILL BE MORE DOMINANT SHOWER/THUNDERSTORM ACTIVITY.
TRENDED THE FORECAST IN THE DIRECTION OF THE FORMER...WITH
SLIGHTLY COOLER /WE ARE TALKING ABOUT 1-2 DEGREES HERE/ AFTERNOON
HIGHS UP NORTH THAN GUIDANCE SUGGESTS...AND PLAYED RAIN CHANCES
TOWARDS THE SOUTHERN ISOLD TO SCT VARIETY INSTEAD OF CONVECTION
BEING TIED TO THE FRONT. THAT SAID...DID LEAVE SLIGHT CHANCES IN
THE NORTH THROUGH THE DAY AND INTO TONIGHT TO ACCOUNT FOR
CONVECTION ALONG THE FRONT.
OTHERWISE...NOT MUCH TO TALK ABOUT IN THE EXTENDED. THE
AFOREMENTIONED FRONT WILL PUSH WELL INTO THE STATE BY THURSDAY.
UPPER LEVEL HIGH PRESSURE SITUATED OVER THE PLAINS WILL BECOME
HIGHLY AMPLIFIED BY LATE THURSDAY. LEFT SOME SLIGHT RAIN CHANCES
OVER THE FAR SOUTH AND FAR SOUTHWEST PARTS OF THE FORECAST AREA
THU AND FRI AFTERNOONS. THERE IS SOME QPF SIGNAL IN NUMERICAL
MODELS BOTH DAYS IN THOSE REGIONS...WHICH SEEMS REASONABLE.
TEMPERATURES WILL NOT COOL DOWN MUCH IN THE SOUTHWEST...BUT HIGHS
IN THE NORTHEAST BY FRIDAY WILL LIKELY NOT HIGH 90 DEGREES.
HOWEVER DRIER AIR WILL FILTER IN ACROSS ARKANSAS SO EVEN WITH
HIGHS IN THE LOW 90S ACROSS THE SOUTHWEST HALF OF THE STATE
THROUGH THE SHORT TERM...THERE WILL BE SOME RELIEF FROM THE HOT
AND MUGGY CONDITIONS HEADING INTO THE WEEKEND.
&&
.LONG TERM...SATURDAY NIGHT THROUGH TUESDAY
THE LONG TERM OFFERS AN ODD SYNOPTIC SETUP FOR JULY. AT THE
BEGINNING...THE RETROGRADING CUTOFF LOW WILL BE MOVING INTO COASTAL
TEXAS...WITH AN ELONGATED UPPER RIDGE SETTING UP OVER THE PLAINS.
THE AFOREMENTIONED LOW WILL BRING MOISTURE UP INTO THE REGION...AND
WITH IT A CHANCE OF SHOWERS/STORMS EACH DAY...WHICH SHOULD MOSTLY BE
DIURNALLY DRIVEN.
WILL CONTINUE TO KEEP RAIN CHANCES SMALL TO ACCOUNT FOR
UNCERTAINTIES WITH THIS SETUP.
IF YOU CAN BELIEVE YOUR EYES...THE EXACT SAME THING LOOKS TO HAPPEN
BY LATE MONDAY INTO TUESDAY...AS THE MODELS ADVERTISE ANOTHER CUTOFF
UPPER LOW FORMING AND RETROGRADING TOWARD THE MID SOUTH REGION. THIS
WILL BRING A REINFORCING SHOT OF AT LEAST SMALL RAIN CHANCES TO END
THE PERIOD.
INITIALLY...TEMPERATURES WILL BE A LITTLE BELOW SEASONAL AVERAGES
DUE TO EASTERLY SURFACE FLOW. BY MONDAY AND TUESDAY...TEMPERATURES
WILL BE A BIT WARMER...BUT WILL BE KEPT IN CHECK BY CLOUD COVER
ASSOCIATED WITH THE UPPER LOWS.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 97 73 90 67 / 20 20 10 10
CAMDEN AR 96 74 95 72 / 30 30 20 20
HARRISON AR 94 72 90 66 / 20 20 10 10
HOT SPRINGS AR 97 75 95 72 / 30 30 20 10
LITTLE ROCK AR 96 75 95 70 / 30 30 20 10
MONTICELLO AR 95 75 94 72 / 30 30 20 10
MOUNT IDA AR 96 75 94 71 / 30 30 20 10
MOUNTAIN HOME AR 96 71 90 66 / 20 20 10 10
NEWPORT AR 96 73 90 67 / 20 20 10 10
PINE BLUFF AR 94 75 94 70 / 30 30 20 10
RUSSELLVILLE AR 98 75 95 71 / 30 20 20 10
SEARCY AR 96 74 92 68 / 30 20 10 10
STUTTGART AR 97 74 93 69 / 30 30 20 10
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...64 / LONG TERM...57
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
217 PM MST WED JUL 10 2013
.SYNOPSIS...
A MUCH MORE FAVORABLE SOUTHEASTERLY FLOW WILL CONTINUE TO IMPORT
DEEPER MONSOON MOISTURE INTO THE REGION OVER THE NEXT COUPLE DAYS.
THIS WILL LEAD TO AN APPRECIABLE INCREASE IN SHOWERS AND
THUNDERSTORMS ACROSS THE ENTIRE AREA THAT WILL LAST 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...HOWEVER A RETURN TO AN ACTIVE MONSOON PERIOD IS LIKELY
AGAIN EARLY NEXT WEEK.
&&
.DISCUSSION...
APPEARS THIS AFTERNOON / EVENING COULD BE SHAPING UP TO BE A LOT
MORE ACTIVE CONVECTIVELY THAN IT HAS BEEN THE LAST SEVERAL DAYS.
AREA SOUNDINGS FROM THIS MORNING SHOW A TONGUE OF HIGH PWAT HAS
WORKED ITS WAY INTO THE CENTRAL DESERTS...ASSISTED BY THE SOUTH TO
SOUTHEAST FLOW THAT WAS SET UP BY THE CONVECTIVE COMPLEX OVER MEXICO
LAST EVENING. INSTABILITY HAS ALSO INCREASED ACROSS THE
REGION...WITH THIS MORNINGS KPSR 12Z SOUNDING SHOWING POSITIVE
ENERGY IN EXCESS OF 2200 J/KG. MODEL SOUNDINGS SHOW AVAILABLE CAPE
OF 1000 TO OVER 1900 J/KG AVAILABLE FOR STORMS TO TAP INTO. SKIES
CLEARED OUT FAIRLY EARLY IN THE WAKE OF THE EARLY MORNING
CONVECTION...ENABLING TEMPERATURES TO BEGIN CLIMBING ACROSS EAST
CENTRAL ARIZONA. ALL THIS POINTS TO INCREASED CHANCES OF STORMS
TODAY. IT WAS NOTED BY OTHER FORECAST STAFF THAT AFTERNOON ACARS
SOUNDINGS FOR PHX WERE SHOWING THE EXISTENCE OF A MID-LEVEL CAP.
THIS COULD BE A HINDRANCE TO EARLY STORM DEVELOPMENT...BUT IT IS
EXPECTED THAT THIS WILL ERODE AND STORMS THAT DUE DEVELOP TO OUR
EAST AND SOUTHEAST WILL BE ABLE TO PROPAGATE INTO THE CENTRAL
DESERTS. LOCAL WRF4KM...U OF A WRF...NMM6KM...AND HRRR MESOSCALE
FORECAST MODELS ALL DEPICT STORMS MOVING FROM THE SOUTHEAST INTO THE
CENTRAL DESERTS FROM THE EVENING TO EARLY MORNING HOURS. AHEAD OF
ARRIVAL OF THE FIRST STORMS BLOWING DUST WILL BE A BIG
CONCERN...ESPECIALLY ALONG THE I-10 CORRIDOR BETWEEN CASA GRANDE AND
PHOENIX. SOME CONVECTION WILL LIKELY LINGER INTO THE MORNING HOURS
AND THE AXIS OF STORMS IS EXPECTED TO SHIFT MORE WESTWARD INTO
WESTERN MARICOPA COUNTY...EASTERN YUMA...AND EASTERN LA PAZ
COUNTIES.
MODELS SHOW PWAT INCREASING THROUGH THURSDAY...WITH ANOTHER
POTENTIALLY ACTIVE DAY THURSDAY AFTERNOON AND EVENING. THIS COULD
CHANGE HOWEVER IF THERE IS WIDESPREAD CONVECTION OVERNIGHT AND
DEBRIS CLOUDINESS HANGS OVER THE REGION THROUGH THE DAY TOMORROW.
ELECTED TO KEEP PRETTY MUCH THE SAME POPS WE HAD GOING IN OUR
EARLIER PACKAGE...WITH CHANCE VALUES FOR THE EASTERN HALF OF THE
FORECAST AREA.
AN UPPER LEVEL TROUGH PUSHING INTO THE PACIFIC NORTHWEST WILL CAUSE
THE RIDGE OVER THE DESERT SOUTHWEST TO SHIFT FURTHER TO THE
SOUTHEAST. THIS WILL BEGIN TO SET UP A DRIER FLOW PATTERN FOR THE
WEEKEND. BOTH THE GFS AND ECMWF SHOW PWAT DECREASING FRIDAY THROUGH
SUNDAY. AS SUCH EXPECT A LOWER GRADE MONSOON AND STORMS TO REMAIN
MAINLY OVER THE HIGHER TERRAIN TO THE EAST AND SOUTHEAST BOTH
SATURDAY AND SUNDAY.
MEDIUM RANGE MODELS ARE IN VERY GOOD AGREEMENT DEPICTING A VERY WELL
DEFINED INVERTED TROUGH/CIRCULATION CENTER HEADED DIRECTLY TOWARDS
ARIZONA EARLY NEXT WEEK. MOISTURE WILL LIKELY SURGE BACK NORTH INTO
THE REGION AHEAD OF THIS SYSTEM...WHILE DYNAMIC SUPPORT INCREASES.
THIS COULD VERY WELL SIGNAL THE START OF ANOTHER MULTI-DAY ACTIVE
PERIOD...AND HAVE STARTED TRENDING DAYTIME TEMPERATURES LOWER AND
POPS HIGHER.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX...KIWA AND KSDL...
THIS AFTERNOON...WESTERLY WINDS ARE EXPECTED TO INCREASE WITH GUSTS
AROUND 20 KTS. THIS EVENING COULD BRING SCATTERED TO POSSIBLY
WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY...POTENTIALLY LASTING
INTO THE OVERNIGHT HOURS. SOME THUNDERSTORMS COULD BE STRONG...AND
CAN/T RULE OUT THE CHANCE OF STRONG WIND GUSTS AND BLOWING DUST
AFFECTING AREA TAF SITES. CONFIDENCE IN TIMING AND EVOLUTION OF THIS
EVENT IS SOMEWHAT ON THE LOW SIDE...BUT IT IS LOOKING LIKE THIS WILL
BE THE FIRST MAJOR MONSOON DAY FOR THE LOWER DESERTS SO FAR THIS
SUMMER.
SOUTHEAST CA AND SOUTHWEST AZ...INCLUDING KIPL AND KBLH...BROKEN
HIGH CLOUDS FINALLY CLEARING A BIT EARLY THIS AFTERNOON ALONG WITH
BREEZY SOUTHERLY WINDS. EXPECTING VERY SLIM STORM/RAIN CHANCES FOR
THE TAF PERIOD...HOWEVER BREEZY OUTFLOW WINDS AND ACCOMPANYING DUST
MAY MOVE INTO THE REGION STARTING THIS EVENING FROM STORMS OVER
ARIZONA AND NORTHERN MEXICO.
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...MCLANE/MO
AVIATION...CDEWEY
FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
125 PM MST WED JUL 10 2013
.UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS.
&&
.SYNOPSIS...
A MUCH MORE FAVORABLE SOUTHEASTERLY FLOW WILL CONTINUE TO IMPORT
DEEPER MONSOON MOISTURE INTO THE REGION OVER THE NEXT COUPLE DAYS.
THIS WILL LEAD TO AN APPRECIABLE INCREASE IN SHOWERS AND
THUNDERSTORMS ACROSS THE ENTIRE AREA THAT WILL LAST 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...HOWEVER A RETURN TO AN ACTIVE MONSOON PERIOD IS LIKELY
AGAIN EARLY NEXT WEEK.
&&
.DISCUSSION...
SO FAR THIS MONSOON SEASON THUNDERSTORMS HAVE STAYED ALONG THE
PERIPHERY OF THE WFO PHOENIX FORECAST AREA...WITH ACTIVITY MAINLY
CONFINED TO THE MOGOLLON RIM AND EXTREME SOUTHEAST ARIZONA. THIS IS
LIKELY TO CHANGE AS EARLY AS TODAY...AS THE AIRMASS HAS
MOISTENED...INSTABILITY HAS INCREASED...FLOW HAS BECOME MORE
SOUTHEAST AND BETTER DYNAMICS ARE IN-PLACE. DESPITE EARLY MORNING
CLOUDINESS FROM CONVECTION SPAWNED BY THE MCS OVER MEXICO...CLEARING
SKIES IN THE EASTERN HALF OF THE FORECAST AREA WILL ALLOW
TEMPERATURES TO BEGIN CLIMBING...HELPING TO DESTABILIZE THE REGION
AND SETTING THE STAGE FOR ADDITIONAL CONVECTION THIS AFTERNOON.
THE 12Z KPSR AND KTWC SOUNDINGS SHOWED PWAT OF 1.88 AND 1.86
RESPECTIVELY. FOR KTWC...THIS WAS SIMILAR TO 24-HOURS AGO...BUT FOR
KPSR THE VALUE WAS ABOUT 4 TENTHS OF AN INCH INCREASE FROM
YESTERDAY. THIS TREND SHOWS DEEPER MOISTURE HAS IN FACT WORKED ITS
WAY INTO THE CENTRAL DESERTS. BOTH SOUNDINGS SHOWED SIGNIFICANT CAPE
AVAILABLE FOR DEVELOPING STORMS TO TAP.
WILL NEED TO WATCH OUTFLOW BOUNDARIES FROM STORMS DEVELOPING TO OUR
EAST AND SOUTHEAST. GUSTY WINDS AND BLOWING DUST WILL OBVIOUSLY BE A
CONCERN...HOWEVER BOUNDARY COLLISIONS WILL BE MORE LIKELY TO TRIGGER
NEW CONVECTION.
FORECAST PACKAGE WAS PRETTY MUCH ON TRACK. TEMPERATURES WERE RUNNING
A FEW DEGREES COOLER THAN FORECAST DUE TO CLOUDINESS SO MADE SOME
MINOR ADJUSTMENTS TO AFTERNOON HIGHS IN SOME LOCATIONS. ALSO LOWERED
POPS THIS MORNING FOR SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA
ZONES.
&&
.PREV DISCUSSION...
ISSUED AT 501 AM MST WED JUL 10 2013
A PARADE OF INVERTED TROUGHS/CIRCULATION CENTERS CONTINUES TO MARCH
WESTWARD ALONG THE SOUTHERN PERIPHERY OF THE SUBTROPICAL HIGH
CENTERED OVER WEST TEXAS THIS MORNING. THE MOST IMPRESSIVE WAVE NEAR
28N 108W HAS SUPPORTED AN IMPRESSIVE MCS OVER NORTHERN MEXICO
FEEDING ON MUCAPES OVER 1000 J/KG AND PWATS EXCEEDING 2.0 INCHES.
CLOUDS TOPS HAVE RAPIDLY WARMED IN THE PAST HOUR WITH A NOTABLE
RAPID DECREASE IN LIGHTNING ACTIVITY...SIGNALING A DOWNTREND IN
CONVECTIVE STRENGTH. NEVERTHELESS...OUTFLOWS...GRAVITY WAVES...AND
INFUSION/ADVECTION OF MOISTURE INTO THE MID LEVELS HAS ALLOWED
SHOWERS TO DEVELOP OVER PARTS OF CENTRAL AND SOUTHWEST ARIZONA
OVERNIGHT. SOME STRONGER WIND GUSTS HAVE ALSO BEEN OBSERVED WITH
THIS ACTIVITY BEHIND OUTFLOW BOUNDARIES...AND EXPECTING THIS TREND
WILL CONTINUE FOR THE NEXT SEVERAL HOURS BEFORE THE ENTIRE SYSTEM
DECAYS. RECENT HRRR OUTPUT HAS BEST CAPTURED RADAR TRENDS...AND HAVE
TAILORED SLIGHT CHANCE SHOWER POPS BASED IN ITS OUTPUT THROUGH THE
MID MORNING AS ACTIVITY WANES.
SEVERAL FACETS OF THE FORECAST SUGGEST LATE THIS AFTERNOON...AND
PARTICULARLY THIS EVENING AND OVERNIGHT WILL BECOME QUITE ACTIVE
OVER MUCH OF THE FORECAST AREA. FIRST...THE PRESENCE OF THE SONORAN
INVERTED TROUGH SHOULD PROVIDE AMPLE DIFLUENCE ALOFT SUPPORTIVE FOR
CONVECTIVE SUSTENANCE. SECOND...A TONGUE OF RICH MOISTURE SHOULD BE
ADVECTED NORTHWEST THROUGHOUT THE DAY...AS EVIDENCED BY OBJECTIVE
ANALYSIS OF +10C H7 DEWPOINTS AND +15C H8 DEWPOINTS LURKING IN
SOUTHEAST ARIZONA (TRANSLATING TO DEEP 11-12 G/KG MIXING RATIOS).
THERE IS ALSO SLIGHTLY COOLER TEMPERATURES IN THIS LAYER WHICH WILL
GRADUALLY ERODE THE CAPPING INVERSION NEAR THE H7 LAYER. FORECAST
SOUNDINGS INDICATE INSTABILITY BECOMING MAXIMIZED AOA 750 J/KG
DURING PEAK HEATING WITH INHIBITION SLOWLY ERODING.
HRRR AND HIGH RESOLUTION WRF NMM CORES (AND TO SOME EXTENT THE
COARSER GFS) ARE IN GENERAL AGREEMENT OF A MORE CLASSIC MONSOON
PATTERN OF CONVERGENT CONVECTIVE COMPLEXES FROM BOTH THE MOGOLLON
RIM AND SERN ARIZONA PROGRESSING THROUGH LOWER ELEVATIONS WESTWARD
TO THE COLORADO RIVER VALLEY THROUGHOUT THE EVENING AND OVERNIGHT.
ON THE OTHER HAND...ARW CORES AND THE ECMWF ARE NOT AS BULLISH WITH
THE MAINTENANCE OF CONVECTION TONIGHT. REGARDLESS...CONCEPTUALLY THE
CURRENT PATTERN FAVORS AT LEAST A PARTIALLY ACTIVE DAY...IF NOT VERY
ACTIVE...THOUGH ENOUGH UNCERTAINTY EXISTS TO PRECLUDE UNUSUALLY HIGH
POPS. ANY STRONGER THUNDERSTORM WILL INITIALLY HAVE THE POSSIBILITY
OF PRODUCING SEVERE WIND GUSTS AND DENSE BLOWING DUST AS T/TD
SPREADS WILL BE ABOVE 40F...THOUGH AS ACTIVITY EVOLVES OVERNIGHT AND
THE ATMOSPHERIC PROFILE BECOME MORE MOIST...THE THREAT SHOULD
TRANSITION TO MORE OF A HEAVY RAIN THREAT (THOUGH STRONGER WINDS
STILL CANNOT BE DISCOUNTED).
LARGE UNCERTAINTY EXISTS REGARDING THE PROCESSION OF TEMPERATURES
AND CONVECTIVE THREAT THURSDAY...PRIMARILY DEPENDENT ON THE
ANTECEDENT CONDITIONS AND ACTIVITY WEDNESDAY NIGHT. SOME MODEL
FORECASTS SUGGEST THURSDAY MAY BE ONE OF THOSE RARE SUMMER DAYS
SOCKED IN WITH CLOUDS...UNUSUALLY COOL TEMPERATURES...AND LITTLE
AVAILABLE INSTABILITY. HOWEVER...IF CLOUDS BEGIN TO CLEAR DURING
PEAK HEATING IT WILL TAKE ONLY A FEW HOURS TO REALIZE MLCAPES ABOVE
1000 J/KG COINCIDENT WITH AMPLE SHEAR AND MOISTURE PROFILES. KEPT
POPS GENERALLY IN THE 30 PERCENT CHANCE CATEGORY GIVEN THE OVERALL
LOW CONFIDENCE FORECAST...THOUGH IF ORGANIZED CONVECTION DOES FORM
IMPACTS COULD BE SIGNIFICANT. REGARDLESS...IT APPEARS TEMPERATURES
WILL STAY IN A BELOW NORMAL CATEGORY (WHETHER A FEW DEGREES OR 10+
DEGREES BELOW REMAINS TO BE SEEN).
FRIDAY COULD BE A SLOWER CONVECTIVE DAY IF THURSDAY ENDS UP BEING AN
ACTIVE MONSOON DAY...OR VICE VERSA COULD BE ACTIVE IF THURSDAY
REMAINS CONTAMINATED AND THE POSSIBILITY OF ANOTHER INVERTED TROUGH
ROTATING WESTWARD FROM THE GULF OF MEXICO CAN COME TO FRUITION.
AMPLE MONSOON MOISTURE WILL STILL BE IN PLACE SUCH THAT AREAWIDE
SLIGHT CHANCE TO CHANCE POPS ARE STILL WARRANTED...THOUGH THE TREND
WAS TO TEMPER POPS SOMEWHAT. AS THE WEST TEXAS SUBTROPICAL HIGH
BEGINS TO STRENGTHEN...EXPAND...AND RETROGRADE WESTWARD...THERE
SHOULD BE A GRADUAL DECREASE IN MOISTURE OVER THE WEEKEND
NECESSITATING LOWER PRECIPITATION CHANCES IN THE FORECAST. AS THE
MOISTURE DECREASES...TEMPERATURES WILL REBOUND WITH HIGHS RETURNING
TO ABOVE NORMAL LEVELS.
MEDIUM RANGE MODELS ARE IN VERY GOOD AGREEMENT DEPICTING A VERY WELL
DEFINED INVERTED TROUGH/CIRCULATION CENTER HEADED DIRECTLY TOWARDS
ARIZONA EARLY NEXT WEEK. MOISTURE WILL LIKELY SURGE BACK NORTH INTO
THE REGION AHEAD OF THIS SYSTEM...WHILE DYNAMIC SUPPORT INCREASES.
THIS COULD VERY WELL SIGNAL THE START OF ANOTHER MULTI-DAY ACTIVE
PERIOD...AND HAVE STARTED TRENDING DAYTIME TEMPERATURES LOWER AND
POPS HIGHER.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX...KIWA AND KSDL...
THIS AFTERNOON...WESTERLY WINDS ARE EXPECTED TO INCREASE WITH GUSTS
AROUND 20 KTS. THIS EVENING COULD BRING SCATTERED TO POSSIBLY
WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY...POTENTIALLY LASTING
INTO THE OVERNIGHT HOURS. SOME THUNDERSTORMS COULD BE STRONG...AND
CAN/T RULE OUT THE CHANCE OF STRONG WIND GUSTS AND BLOWING DUST
AFFECTING AREA TAF SITES. CONFIDENCE IN TIMING AND EVOLUTION OF THIS
EVENT IS SOMEWHAT ON THE LOW SIDE...BUT IT IS LOOKING LIKE THIS WILL
BE THE FIRST MAJOR MONSOON DAY FOR THE LOWER DESERTS SO FAR THIS
SUMMER.
SOUTHEAST CA AND SOUTHWEST AZ...INCLUDING KIPL AND KBLH...BROKEN
HIGH CLOUDS FINALLY CLEARING A BIT EARLY THIS AFTERNOON ALONG WITH
BREEZY SOUTHERLY WINDS. EXPECTING VERY SLIM STORM/RAIN CHANCES FOR
THE TAF PERIOD...HOWEVER BREEZY OUTFLOW WINDS AND ACCOMPANYING DUST
MAY MOVE INTO THE REGION STARTING THIS EVENING FROM STORMS OVER
ARIZONA AND NORTHERN MEXICO.
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...MCLANE/MO
AVIATION...CDEWEY
FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS TUCSON AZ
124 AM MST WED JUL 10 2013
.SYNOPSIS...A FAVORABLE SOUTHEASTERLY FLOW REGIME WILL RESULT IN
GREATER THUNDERSTORM COVERAGE THROUGH THURSDAY. THUNDERSTORM
CHANCES WILL GRADUALLY DECREASE FRIDAY THROUGH SUNDAY. THEREAFTER...
THUNDERSTORM COVERAGE WILL INCREASE EARLY NEXT WEEK AS A LOW
PRESSURE SYSTEM APPROACHES FROM THE EAST. EXPECT COOLER DAYTIME
TEMPERATURES BY THURSDAY FOLLOWED BY A WARMING TREND THIS WEEKEND.
&&
.DISCUSSION...THUNDERSTORM ARE FORMING ACROSS SANTA CRUZ COUNTY AND
OVER THE PINALINOS MTNS...WHICH IS ABOUT AN HOUR LATER THAN MODELS
PROGGED. CONVECTIVE TEMP IN TUCSON BASED ON THIS MORNINGS SOUNDING
IS 95 DEGREES AND WE ARE CURRENTLY HOVERING AT 94. STILL EXPECTING
AN ACTIVE DAY THIS AFTERNOON...BUT THE LATEST HRRR DATA HINTS THAT
WE HAVE TOO MUCH OF A GOOD THING TODAY. THE ABUNDANT MOISTURE AND
JUST ENOUGH HEATING SEEM TO BREAKOUT WIDESPREAD WEAK CONVECTION.
FROM THERE...THE HEATING IS MARGINALIZED AND THE WE FAIL TO SEE THE
ORGANIZED CONVECTION PREVIOUSLY NOTED IN THE MODELS. BUT THE DAY IS
YOUNG AND I AM NOT READY TO WRITE OFF THE ACTIVITY JUST YET.
FOR TOMORROW...FORECAST SOUNDINGS SUGGEST SLIGHTLY DRIER MIDLEVELS
TOMORROW...BUT PWATS ONLY DIP BY A TENTH OF AN INCH. THE UPPER HIGH
WILL SLIDE EAST AND KEEP AZ IN FAVORABLE SOUTHEAST FLOW SO I AM NOT
CONFIDENT THIS SLIGHT DECREASE IN MOISTURE WILL ACTUALLY TRANSPIRE.
MY MAIN CONCERN FOR CONVECTION TOMORROW WILL BE THE EXTENT OF THE
ACTIVITY OVERNIGHT TONIGHT...AND LINGERING MORNING CLOUD COVER
TOMORROW. IF THE MCS SITUATION DEVELOPS THEN WE MIGHT BE TOO WORKED
OVER TO SEE MID DAY CONVECTION TOMORROW. THE UOFA NAM WRF SEEMS TO
FOLLOW THIS THEME AND KEEPS CONVECTION AT BAY UNTIL AFTER 6 PM
TOMORROW.
THE HIGH CONTINUES A SLOW MIGRATION EASTWARD THROUGH FRIDAY AND WE
START TO SEE THE MID LEVEL FLOW WEAKEN. GIVEN THAT TREND...STILL
EXPECT SOME CONVECTION FRIDAY AND SATURDAY...BUT INCREASING MID
LEVEL DRYING BY SUNDAY SHOULD LIMIT OUR PRECIP CHANCES.
A BIG CHANGE WOULD QUICKLY FOLLOW THE POTENTIAL DRYING ON SUNDAY.
THE MODELS CONTINUE TO SHOW AN INVERTED TROUGH MOVING INTO SE AZ
STARTING MONDAY MORNING. THE LATEST MODEL RUNS HAVE SLOWED THE
SYSTEM ONCE IT REACH AZ KEEPING THE SYSTEM INFLUENCING AZ THROUGH
FRIDAY. THAT SEEMS A BIT LONG...BUT I DO BUY THE SLOW MOVING
SOLUTION DUE TO THE DEVELOPING UPPER TROUGH OVER THE PACIFIC
NORTHWEST. OUR INVERTED TROUGH WOULD SIT BETWEEN THE PACIFIC TROUGH
AND THE MONSOON RIDGE OVER THE GREAT PLAINS. THESE INVERTED TROUGHS
OFTEN BRING WIDESPREAD RAIN TO AZ AND CAN KEEP OVERNIGHT CONVECTION
ACTIVE. SO I INCREASED POPS A BIT IN THE EXTENDED ESPECIALLY DURING
THE OVERNIGHT HOURS.
JJB
&&
.AVIATION...EXPECT ANOTHER ROUND OF THUNDERSTORMS THIS AFTERNOON
INTO THE EVENING THROUGH 11/06Z. LCL CIGS BKN020-030 AGL NEAR THE
STORMS. SMALL HAIL LIKELY NEAR THE THUNDERSTORM CORE WITH LOCALLY
HEAVY RAINFALL. STRONG ERRATIC WIND GUSTS NEAR 50KTS WITH THE
STRONGEST THUNDERSTORMS. STORM MOTION FROM THE ESE TOWARDS THE WNW
10-15 KTS. LIGHT WINDS WEST TO NORTHWEST 10-15 KTS BECOMING LIGHT
AND VARIABLE AFT 11/04Z.
&&
.FIRE WEATHER...SCATTERED MAINLY LATE AFTERNOON AND EVENING SHOWERS
AND THUNDERSTORMS WILL CONTINUE THROUGH THIS WEEK. AN UNUSUALLY
MOISTURE AIR MASS IS OVER SOUTHERN ARIZONA FOR THIS TIME OF YEAR.
THE STRONGER THUNDERSTORMS WILL PRODUCE GUSTY AND ERRATIC WINDS AND
LOCALLY HEAVY RAINS. THE STRONGEST THUNDERSTORMS ARE EXPECTED
TONIGHT THROUGH TOMORROW. OUTSIDE OF THE THUNDERSTORM ACTIVITY...
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.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
DISCUSSION...BROST
AVIATION/FIRE WEATHER...SAMPSON
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
952 AM MST WED JUL 10 2013
.SYNOPSIS...
A MUCH MORE FAVORABLE SOUTHEASTERLY FLOW WILL CONTINUE TO IMPORT
DEEPER MONSOON MOISTURE INTO THE REGION OVER THE NEXT COUPLE DAYS.
THIS WILL LEAD TO AN APPRECIABLE INCREASE IN SHOWERS AND
THUNDERSTORMS ACROSS THE ENTIRE AREA THAT WILL LAST 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...HOWEVER A RETURN TO AN ACTIVE MONSOON PERIOD IS LIKELY
AGAIN EARLY NEXT WEEK.
&&
.DISCUSSION...
SO FAR THIS MONSOON SEASON THUNDERSTORMS HAVE STAYED ALONG THE
PERIPHERY OF THE WFO PHOENIX FORECAST AREA...WITH ACTIVITY MAINLY
CONFINED TO THE MOGOLLON RIM AND EXTREME SOUTHEAST ARIZONA. THIS IS
LIKELY TO CHANGE AS EARLY AS TODAY...AS THE AIRMASS HAS
MOISTENED...INSTABILITY HAS INCREASED...FLOW HAS BECOME MORE
SOUTHEAST AND BETTER DYNAMICS ARE IN-PLACE. DESPITE EARLY MORNING
CLOUDINESS FROM CONVECTION SPAWNED BY THE MCS OVER MEXICO...CLEARING
SKIES IN THE EASTERN HALF OF THE FORECAST AREA WILL ALLOW
TEMPERATURES TO BEGIN CLIMBING...HELPING TO DESTABILIZE THE REGION
AND SETTING THE STAGE FOR ADDITIONAL CONVECTION THIS AFTERNOON.
THE 12Z KPSR AND KTWC SOUNDINGS SHOWED PWAT OF 1.88 AND 1.86
RESPECTIVELY. FOR KTWC...THIS WAS SIMILAR TO 24-HOURS AGO...BUT FOR
KPSR THE VALUE WAS ABOUT 4 TENTHS OF AN INCH INCREASE FROM
YESTERDAY. THIS TREND SHOWS DEEPER MOISTURE HAS IN FACT WORKED ITS
WAY INTO THE CENTRAL DESERTS. BOTH SOUNDINGS SHOWED SIGNIFICANT CAPE
AVAILABLE FOR DEVELOPING STORMS TO TAP.
WILL NEED TO WATCH OUTFLOW BOUNDARIES FROM STORMS DEVELOPING TO OUR
EAST AND SOUTHEAST. GUSTY WINDS AND BLOWING DUST WILL OBVIOUSLY BE A
CONCERN...HOWEVER BOUNDARY COLLISIONS WILL BE MORE LIKELY TO TRIGGER
NEW CONVECTION.
FORECAST PACKAGE WAS PRETTY MUCH ON TRACK. TEMPERATURES WERE RUNNING
A FEW DEGREES COOLER THAN FORECAST DUE TO CLOUDINESS SO MADE SOME
MINOR ADJUSTMENTS TO AFTERNOON HIGHS IN SOME LOCATIONS. ALSO LOWERED
POPS THIS MORNING FOR SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA
ZONES.
&&
.PREV DISCUSSION...
ISSUED AT 501 AM MST WED JUL 10 2013
A PARADE OF INVERTED TROUGHS/CIRCULATION CENTERS CONTINUES TO MARCH
WESTWARD ALONG THE SOUTHERN PERIPHERY OF THE SUBTROPICAL HIGH
CENTERED OVER WEST TEXAS THIS MORNING. THE MOST IMPRESSIVE WAVE NEAR
28N 108W HAS SUPPORTED AN IMPRESSIVE MCS OVER NORTHERN MEXICO
FEEDING ON MUCAPES OVER 1000 J/KG AND PWATS EXCEEDING 2.0 INCHES.
CLOUDS TOPS HAVE RAPIDLY WARMED IN THE PAST HOUR WITH A NOTABLE
RAPID DECREASE IN LIGHTNING ACTIVITY...SIGNALING A DOWNTREND IN
CONVECTIVE STRENGTH. NEVERTHELESS...OUTFLOWS...GRAVITY WAVES...AND
INFUSION/ADVECTION OF MOISTURE INTO THE MID LEVELS HAS ALLOWED
SHOWERS TO DEVELOP OVER PARTS OF CENTRAL AND SOUTHWEST ARIZONA
OVERNIGHT. SOME STRONGER WIND GUSTS HAVE ALSO BEEN OBSERVED WITH
THIS ACTIVITY BEHIND OUTFLOW BOUNDARIES...AND EXPECTING THIS TREND
WILL CONTINUE FOR THE NEXT SEVERAL HOURS BEFORE THE ENTIRE SYSTEM
DECAYS. RECENT HRRR OUTPUT HAS BEST CAPTURED RADAR TRENDS...AND HAVE
TAILORED SLIGHT CHANCE SHOWER POPS BASED IN ITS OUTPUT THROUGH THE
MID MORNING AS ACTIVITY WANES.
SEVERAL FACETS OF THE FORECAST SUGGEST LATE THIS AFTERNOON...AND
PARTICULARLY THIS EVENING AND OVERNIGHT WILL BECOME QUITE ACTIVE
OVER MUCH OF THE FORECAST AREA. FIRST...THE PRESENCE OF THE SONORAN
INVERTED TROUGH SHOULD PROVIDE AMPLE DIFLUENCE ALOFT SUPPORTIVE FOR
CONVECTIVE SUSTENANCE. SECOND...A TONGUE OF RICH MOISTURE SHOULD BE
ADVECTED NORTHWEST THROUGHOUT THE DAY...AS EVIDENCED BY OBJECTIVE
ANALYSIS OF +10C H7 DEWPOINTS AND +15C H8 DEWPOINTS LURKING IN
SOUTHEAST ARIZONA (TRANSLATING TO DEEP 11-12 G/KG MIXING RATIOS).
THERE IS ALSO SLIGHTLY COOLER TEMPERATURES IN THIS LAYER WHICH WILL
GRADUALLY ERODE THE CAPPING INVERSION NEAR THE H7 LAYER. FORECAST
SOUNDINGS INDICATE INSTABILITY BECOMING MAXIMIZED AOA 750 J/KG
DURING PEAK HEATING WITH INHIBITION SLOWLY ERODING.
HRRR AND HIGH RESOLUTION WRF NMM CORES (AND TO SOME EXTENT THE
COARSER GFS) ARE IN GENERAL AGREEMENT OF A MORE CLASSIC MONSOON
PATTERN OF CONVERGENT CONVECTIVE COMPLEXES FROM BOTH THE MOGOLLON
RIM AND SERN ARIZONA PROGRESSING THROUGH LOWER ELEVATIONS WESTWARD
TO THE COLORADO RIVER VALLEY THROUGHOUT THE EVENING AND OVERNIGHT.
ON THE OTHER HAND...ARW CORES AND THE ECMWF ARE NOT AS BULLISH WITH
THE MAINTENANCE OF CONVECTION TONIGHT. REGARDLESS...CONCEPTUALLY THE
CURRENT PATTERN FAVORS AT LEAST A PARTIALLY ACTIVE DAY...IF NOT VERY
ACTIVE...THOUGH ENOUGH UNCERTAINTY EXISTS TO PRECLUDE UNUSUALLY HIGH
POPS. ANY STRONGER THUNDERSTORM WILL INITIALLY HAVE THE POSSIBILITY
OF PRODUCING SEVERE WIND GUSTS AND DENSE BLOWING DUST AS T/TD
SPREADS WILL BE ABOVE 40F...THOUGH AS ACTIVITY EVOLVES OVERNIGHT AND
THE ATMOSPHERIC PROFILE BECOME MORE MOIST...THE THREAT SHOULD
TRANSITION TO MORE OF A HEAVY RAIN THREAT (THOUGH STRONGER WINDS
STILL CANNOT BE DISCOUNTED).
LARGE UNCERTAINTY EXISTS REGARDING THE PROCESSION OF TEMPERATURES
AND CONVECTIVE THREAT THURSDAY...PRIMARILY DEPENDENT ON THE
ANTECEDENT CONDITIONS AND ACTIVITY WEDNESDAY NIGHT. SOME MODEL
FORECASTS SUGGEST THURSDAY MAY BE ONE OF THOSE RARE SUMMER DAYS
SOCKED IN WITH CLOUDS...UNUSUALLY COOL TEMPERATURES...AND LITTLE
AVAILABLE INSTABILITY. HOWEVER...IF CLOUDS BEGIN TO CLEAR DURING
PEAK HEATING IT WILL TAKE ONLY A FEW HOURS TO REALIZE MLCAPES ABOVE
1000 J/KG COINCIDENT WITH AMPLE SHEAR AND MOISTURE PROFILES. KEPT
POPS GENERALLY IN THE 30 PERCENT CHANCE CATEGORY GIVEN THE OVERALL
LOW CONFIDENCE FORECAST...THOUGH IF ORGANIZED CONVECTION DOES FORM
IMPACTS COULD BE SIGNIFICANT. REGARDLESS...IT APPEARS TEMPERATURES
WILL STAY IN A BELOW NORMAL CATEGORY (WHETHER A FEW DEGREES OR 10+
DEGREES BELOW REMAINS TO BE SEEN).
FRIDAY COULD BE A SLOWER CONVECTIVE DAY IF THURSDAY ENDS UP BEING AN
ACTIVE MONSOON DAY...OR VICE VERSA COULD BE ACTIVE IF THURSDAY
REMAINS CONTAMINATED AND THE POSSIBILITY OF ANOTHER INVERTED TROUGH
ROTATING WESTWARD FROM THE GULF OF MEXICO CAN COME TO FRUITION.
AMPLE MONSOON MOISTURE WILL STILL BE IN PLACE SUCH THAT AREAWIDE
SLIGHT CHANCE TO CHANCE POPS ARE STILL WARRANTED...THOUGH THE TREND
WAS TO TEMPER POPS SOMEWHAT. AS THE WEST TEXAS SUBTROPICAL HIGH
BEGINS TO STRENGTHEN...EXPAND...AND RETROGRADE WESTWARD...THERE
SHOULD BE A GRADUAL DECREASE IN MOISTURE OVER THE WEEKEND
NECESSITATING LOWER PRECIPITATION CHANCES IN THE FORECAST. AS THE
MOISTURE DECREASES...TEMPERATURES WILL REBOUND WITH HIGHS RETURNING
TO ABOVE NORMAL LEVELS.
MEDIUM RANGE MODELS ARE IN VERY GOOD AGREEMENT DEPICTING A VERY WELL
DEFINED INVERTED TROUGH/CIRCULATION CENTER HEADED DIRECTLY TOWARDS
ARIZONA EARLY NEXT WEEK. MOISTURE WILL LIKELY SURGE BACK NORTH INTO
THE REGION AHEAD OF THIS SYSTEM...WHILE DYNAMIC SUPPORT INCREASES.
THIS COULD VERY WELL SIGNAL THE START OF ANOTHER MULTI-DAY ACTIVE
PERIOD...AND HAVE STARTED TRENDING DAYTIME TEMPERATURES LOWER AND
POPS HIGHER.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX...KIWA AND KSDL...
FAIRLY STRONG WESTERLY LOW LEVEL FLOW HAS PERSISTED OVERNIGHT
KEEPING DRAINAGE WINDS AT BAY...AND WILL LIKELY CONTINUE TO DO SO
FOR THE REST OF THIS MORNING. BY THE LATE AFTERNOON...WESTERLY WINDS
ARE EXPECTED TO INCREASE WITH GUSTS AROUND 20 KTS. THIS EVENING
COULD BRING SCATTERED TO POSSIBLY WIDESPREAD SHOWER AND THUNDERSTORM
ACTIVITY...POTENTIALLY LASTING INTO THE OVERNIGHT HOURS. SOME
THUNDERSTORMS COULD BE STRONG...AND CAN/T RULE OUT THE CHANCE OF
STRONG WIND GUSTS AND BLOWING DUST AFFECTING AREA TAF SITES.
CONFIDENCE IN TIMING AND EVOLUTION OF THIS EVENT IS SOMEWHAT ON THE
LOW SIDE...BUT IT IS LOOKING LIKE THIS WILL BE THE FIRST MAJOR
MONSOON DAY FOR THE LOWER DESERTS SO FAR THIS SUMMER.
SOUTHEAST CA AND SOUTHWEST AZ...INCLUDING KIPL AND KBLH...
BROKEN HIGH CLOUDS WILL PERSIST THROUGH THE MORNING HOURS ALONG WITH
CONTINUED BREEZY SOUTHERLY WINDS. EXPECTING VERY SLIM STORM/RAIN
CHANCES FOR THE TAF PERIOD...HOWEVER BREEZY OUTFLOW WINDS AND
ACCOMPANYING DUST MAY MOVE INTO THE REGION STARTING THIS EVENING
FROM STORMS OVER ARIZONA AND NORTHERN MEXICO.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
FRIDAY THROUGH TUESDAY...
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...MCLANE/MO
AVIATION...KUHLMAN
FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS TUCSON AZ
925 AM MST WED JUL 10 2013
.SYNOPSIS...A FAVORABLE SOUTHEASTERLY FLOW REGIME WILL RESULT IN
GREATER THUNDERSTORM COVERAGE THROUGH THURSDAY. THUNDERSTORM
CHANCES WILL GRADUALLY DECREASE FRIDAY THROUGH SUNDAY. THEREAFTER...
THUNDERSTORM COVERAGE WILL INCREASE EARLY NEXT WEEK AS A LOW
PRESSURE SYSTEM APPROACHES FROM THE EAST. EXPECT COOLER DAYTIME
TEMPERATURES BY THURSDAY FOLLOWED BY A WARMING TREND THIS WEEKEND.
&&
.DISCUSSION...INTERESTING DAY IN STORE FOR SOUTHEAST ARIZONA. VIS
SATELLITE AND SURFACE OBS DEPICT MORE CLEARING THIS MORNING THAN
YESTERDAY. KTUS IS CURRENTLY RUNNING A DEGREE OR TWO WARMER THAN
YESTERDAY SO WE STILL HAVE SOME POTENTIAL TO HIT 100 DEGREES AND
BREAK THE ALL TIME RECORD CONSECUTIVE STREAK OF HIGH TEMPS OF 100
DEGREES OR GREATER. THE BIGGER CONCERN FROM THE CLEAR SKIES IS THE
IMPROVED HEATING THAT WILL CONTINUE THROUGH MID MORNING AND HOW THIS
HEATING WILL INFLUENCE OUR CONVECTIVE POTENTIAL TODAY. MORNING
SOUNDING WAS IMPRESSIVE. VERY HIGH PRECIP WATER VALUES NEAR 1.9
INCHES WHICH IS ABOVE THE 99TH PERCENTILE FOR THIS TIME OF YEAR. SFC
DEW POINTS ACROSS SE AZ AR IN THE MID 60S WITH THE MOIST AIRMASS
EXTENDING NORTH OF KPHX. ABUNDANT CAPE EVIDENT ON THE 12Z SOUNDING
WITH THE MEAN LAYER CAPE VALUES ARE RUNNING ABOVE THE 75TH
PERCENTILE FOR THIS TIME OF YEAR. DCAPE IS ALSO LOOKING GOOD AND WE
HAVE ENOUGH SHEAR IN PLACE TO BE CONCERNED FOR ISOLATED SUPERCELLS
TODAY.
SO ATMOSPHERIC DATA CERTAINLY POINTS TOWARDS INCREASED ACTIVITY
TODAY AND WITH THE CLEAR MORNING SKIES...OTHER THAN A FEW CLOUDS
HANGING AROUND COCHISE COUNTY...ANTICIPATE AN EARLIER START THAN
YESTERDAY.
THAT LEADS ME TO THE HIGH RES MODELS. THE UOFA WRF...OUR LOCAL
WRF...AND THE HRRR ALL POINT TOWARD SIMILAR SOLUTIONS. BASED ON THE
MODELS...CONVECTION SHOULD BEGIN BY NOON TODAY ALONG THE
INTERNATIONAL BORDER NEAR SANTA CRUZ COUNTY...AND THEN BUILD
NORTHWEST ACROSS PIMA COUNTY. THE MODELS ARE LESS OPTIMISTIC FOR
ACTIVITY ACROSS COCHISE COUNTY...LIKELY DUE TO THE MORNING CLOUD
COVER...BUT THINKING THESE AREAS MAY SEE THE ACTIVITY LATER IN THE
EVENING ONCE THE CONVECTIVE TEMPS ARE MET.
SO...CONCERNS TODAY RUN THE GAMUT. SEVERE STORMS WITH STRONG
DOWNDRAFTS AND HAIL AND POSSIBLY A SUPERCELL OR TWO...TRANSITIONING
TO AN MCS LATER IN THE AFTERNOON. ALSO...THE HIGH MOISTURE CONTENT
COMBINED WITH THE HEAVY RAINFALL WE EXPERIENCED YESTERDAY IN SOME
LOCATIONS WOULD CERTAINLY FAVOR FLASH FLOODING. FINALLY...THE STORM
MOTIONS TODAY ALSO SUGGEST DUST STORM POTENTIAL.
SE AZ IS CURRENTLY UNDER A SLIGHT RISK.
JJB
&&
.AVIATION...SCT120 NEAR THE INTERNATIONAL BORDER BECOMING MOSTLY
SUNNY BY MID-MORNING. EXPECT ANOTHER ROUND OF THUNDERSTORMS THIS
AFTERNOON INTO THE EVENING OR FROM 10/18Z THROUGH 11/06Z. LCL CIGS
BKN025-030 AGL NEAR THE STORMS. SMALL HAIL LIKELY NEAR THE
THUNDERSTORM CORE WITH LOCALLY HEAVY RAINFALL. STRONG ERRATIC WIND
GUSTS NEAR 55KTS WITH THE STRONGEST THUNDERSTORMS. STORM MOTION FROM
THE EAST TOWARDS THE WEST 10-15 KTS. OUTSIDE OF THE STORMS EXPECT
LIGHT VARIABLE WINDS THIS MORNING THEN BECOMING WEST TO NORTHWEST
10-15 KTS AFT 10/20Z AND BECOMING LIGHT AND VARIABLE AGAIN AFT
11/04Z.
&&
.FIRE WEATHER...SCATTERED MAINLY LATE AFTERNOON AND EVENING SHOWERS
AND THUNDERSTORMS WILL CONTINUE THROUGH THE END OF THE WEEK. THE
STRONGER THUNDERSTORMS WILL PRODUCE GUSTY AND ERRATIC WINDS AND THE
POTENTIAL FOR LOCALLY HEAVY RAINS WILL CONTINUE INTO THURSDAY. AN
UNUSUALLY MOISTURE AIR MASS IS OVER SOUTHERN ARIZONA FOR THIS TIME
OF YEAR. AWAY FROM THE THUNDERSTORM ACTIVITY...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.
&&
.PREV DISCUSSION...HIGH PRESSURE ALOFT CENTERED NEAR THE FOUR
CORNERS REGION EARLY THIS MORNING WILL MOVE EWD INTO THE CENTRAL
CONUS PLAINS BY MIDDAY FRI. A DEEPER SELY FLOW REGIME WILL BECOME
ESTABLISHED LATER TODAY AND CONTINUE INTO THUR. 10/00Z NAM/GFS/
ECMWF CONTINUED WITH GOOD RUN-TO-RUN CONSISTENCY BY DEPICTING HIGHER
POPS TO OCCUR THIS AFTERNOON INTO TONIGHT AND AGAIN THUR.
THUS...FORECAST CONFIDENCE IS FAIRLY HIGH THAT AN ACTIVE CONVECTIVE
PERIOD WILL OCCUR DURING THE AFOREMENTIONED TIME PERIODS. SIMILAR
PRECIP WATER VALUES SHOULD TRANSLATE INTO SIMILAR RAINFALL AMOUNTS
THAT WERE RECORDED TUE AFTERNOON AND TUE EVENING. HAVE DEPICTED
AREAS OF BLOWING DUST LATE THIS AFTERNOON AND EARLY THIS EVENING
MAINLY ALONG THE INTERSTATE 10 CORRIDOR NW OF TUCSON AS TSTMS MOVE
NWWD INTO SOUTH CENTRAL PINAL COUNTY.
A GRADUAL DECREASE IN SHOWER/TSTM COVERAGE IS FORECAST TO OCCUR
FRI-SUN AS THE GFS/ECMWF DEPICT THE BULK OF DEEPER MOISTURE TO SHIFT
NW OF THE AREA. HAVE TRENDED POPS DOWNWARD ACCORDINGLY FRI-SUN TO
REFLECT THIS SCENARIO. THEREAFTER...SHOWER/TSTM COVERAGE SHOULD
INCREASE MARKEDLY MON AS AN INVERTED TROUGH ADVANCES WWD ACROSS
CHIHUAHUA.
SCATTERED TO PERHAPS NUMEROUS SHOWERS/TSTMS ARE FORECAST MON
AFTERNOON AND MON EVENING FROM TUCSON EWD/SWD. ISOLATED TO SCATTERED
SHOWERS/TSTMS ARE ON TAP ACROSS WRN PIMA COUNTY AND SOUTH CENTRAL
PINAL COUNTY. AMPLE MOISTURE IN COMBINATION WITH THE STATIONARY
UPPER LEVEL LOW PRESSURE SYSTEM ACROSS NRN SONORA WILL JUSTIFY
SCATTERED MAINLY AFTERNOON/EVENING SHOWERS/TSTMS ACROSS MUCH OF SE
AZ TUE. THIS SYSTEM HOLDS THE POTENTIAL TO BRING CONSIDERABLE
RAINFALL TO SE AZ MON-TUE.
HIGH TEMPS TODAY WILL BE ABOUT 2-3 DEGS F COOLER VERSUS MAX TEMPS
ACHIEVED TUE. DAYTIME TEMPS THUR WILL BE ABOUT 2-4 DEGS F COOLER
VERSUS TODAY...THEN A WARMING TREND WILL OCCUR FRI-SUN IN RESPONSE
TO A SLIGHTLY DRIER ENVIRONMENT.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
DISCUSSION...BROST
AVIATION/FIRE WEATHER...SAMPSON
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
501 AM MST WED JUL 10 2013
.UPDATE...UPDATED AVIATION AND FIRE WX DISCUSSIONS.
&&
.SYNOPSIS...
A MUCH MORE FAVORABLE SOUTHEASTERLY FLOW WILL CONTINUE TO IMPORT
DEEPER MONSOON MOISTURE INTO THE REGION OVER THE NEXT COUPLE DAYS.
THIS WILL LEAD TO AN APPRECIABLE INCREASE IN SHOWERS AND
THUNDERSTORMS ACROSS THE ENTIRE AREA THAT WILL LAST 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...HOWEVER A RETURN TO AN ACTIVE MONSOON PERIOD IS LIKELY
AGAIN EARLY NEXT WEEK.
&&
.DISCUSSION...
A PARADE OF INVERTED TROUGHS/CIRCULATION CENTERS CONTINUES TO MARCH
WESTWARD ALONG THE SOUTHERN PERIPHERY OF THE SUBTROPICAL HIGH
CENTERED OVER WEST TEXAS THIS MORNING. THE MOST IMPRESSIVE WAVE NEAR
28N 108W HAS SUPPORTED AN IMPRESSIVE MCS OVER NORTHERN MEXICO
FEEDING ON MUCAPES OVER 1000 J/KG AND PWATS EXCEEDING 2.0 INCHES.
CLOUDS TOPS HAVE RAPIDLY WARMED IN THE PAST HOUR WITH A NOTABLE
RAPID DECREASE IN LIGHTNING ACTIVITY...SIGNALING A DOWNTREND IN
CONVECTIVE STRENGTH. NEVERTHELESS...OUTFLOWS...GRAVITY WAVES...AND
INFUSION/ADVECTION OF MOISTURE INTO THE MID LEVELS HAS ALLOWED
SHOWERS TO DEVELOP OVER PARTS OF CENTRAL AND SOUTHWEST ARIZONA
OVERNIGHT. SOME STRONGER WIND GUSTS HAVE ALSO BEEN OBSERVED WITH
THIS ACTIVITY BEHIND OUTFLOW BOUNDARIES...AND EXPECTING THIS TREND
WILL CONTINUE FOR THE NEXT SEVERAL HOURS BEFORE THE ENTIRE SYSTEM
DECAYS. RECENT HRRR OUTPUT HAS BEST CAPTURED RADAR TRENDS...AND HAVE
TAILORED SLIGHT CHANCE SHOWER POPS BASED IN ITS OUTPUT THROUGH THE
MID MORNING AS ACTIVITY WANES.
SEVERAL FACETS OF THE FORECAST SUGGEST LATE THIS AFTERNOON...AND
PARTICULARLY THIS EVENING AND OVERNIGHT WILL BECOME QUITE ACTIVE
OVER MUCH OF THE FORECAST AREA. FIRST...THE PRESENCE OF THE SONORAN
INVERTED TROUGH SHOULD PROVIDE AMPLE DIFLUENCE ALOFT SUPPORTIVE FOR
CONVECTIVE SUSTENANCE. SECOND...A TONGUE OF RICH MOISTURE SHOULD BE
ADVECTED NORTHWEST THROUGHOUT THE DAY...AS EVIDENCED BY OBJECTIVE
ANALYSIS OF +10C H7 DEWPOINTS AND +15C H8 DEWPOINTS LURKING IN
SOUTHEAST ARIZONA (TRANSLATING TO DEEP 11-12 G/KG MIXING RATIOS).
THERE IS ALSO SLIGHTLY COOLER TEMPERATURES IN THIS LAYER WHICH WILL
GRADUALLY ERODE THE CAPPING INVERSION NEAR THE H7 LAYER. FORECAST
SOUNDINGS INDICATE INSTABILITY BECOMING MAXIMIZED AOA 750 J/KG
DURING PEAK HEATING WITH INHIBITION SLOWLY ERODING.
HRRR AND HIGH RESOLUTION WRF NMM CORES (AND TO SOME EXTENT THE
COARSER GFS) ARE IN GENERAL AGREEMENT OF A MORE CLASSIC MONSOON
PATTERN OF CONVERGENT CONVECTIVE COMPLEXES FROM BOTH THE MOGOLLON
RIM AND SERN ARIZONA PROGRESSING THROUGH LOWER ELEVATIONS WESTWARD
TO THE COLORADO RIVER VALLEY THROUGHOUT THE EVENING AND OVERNIGHT.
ON THE OTHER HAND...ARW CORES AND THE ECMWF ARE NOT AS BULLISH WITH
THE MAINTENANCE OF CONVECTION TONIGHT. REGARDLESS...CONCEPTUALLY THE
CURRENT PATTERN FAVORS AT LEAST A PARTIALLY ACTIVE DAY...IF NOT VERY
ACTIVE...THOUGH ENOUGH UNCERTAINTY EXISTS TO PRECLUDE UNUSUALLY HIGH
POPS. ANY STRONGER THUNDERSTORM WILL INITIALLY HAVE THE POSSIBILITY
OF PRODUCING SEVERE WIND GUSTS AND DENSE BLOWING DUST AS T/TD
SPREADS WILL BE ABOVE 40F...THOUGH AS ACTIVITY EVOLVES OVERNIGHT AND
THE ATMOSPHERIC PROFILE BECOME MORE MOIST...THE THREAT SHOULD
TRANSITION TO MORE OF A HEAVY RAIN THREAT (THOUGH STRONGER WINDS
STILL CANNOT BE DISCOUNTED).
LARGE UNCERTAINTY EXISTS REGARDING THE PROCESSION OF TEMPERATURES
AND CONVECTIVE THREAT THURSDAY...PRIMARILY DEPENDENT ON THE
ANTECEDENT CONDITIONS AND ACTIVITY WEDNESDAY NIGHT. SOME MODEL
FORECASTS SUGGEST THURSDAY MAY BE ONE OF THOSE RARE SUMMER DAYS
SOCKED IN WITH CLOUDS...UNUSUALLY COOL TEMPERATURES...AND LITTLE
AVAILABLE INSTABILITY. HOWEVER...IF CLOUDS BEGIN TO CLEAR DURING
PEAK HEATING IT WILL TAKE ONLY A FEW HOURS TO REALIZE MLCAPES ABOVE
1000 J/KG COINCIDENT WITH AMPLE SHEAR AND MOISTURE PROFILES. KEPT
POPS GENERALLY IN THE 30 PERCENT CHANCE CATEGORY GIVEN THE OVERALL
LOW CONFIDENCE FORECAST...THOUGH IF ORGANIZED CONVECTION DOES FORM
IMPACTS COULD BE SIGNIFICANT. REGARDLESS...IT APPEARS TEMPERATURES
WILL STAY IN A BELOW NORMAL CATEGORY (WHETHER A FEW DEGREES OR 10+
DEGREES BELOW REMAINS TO BE SEEN).
FRIDAY COULD BE A SLOWER CONVECTIVE DAY IF THURSDAY ENDS UP BEING AN
ACTIVE MONSOON DAY...OR VICE VERSA COULD BE ACTIVE IF THURSDAY
REMAINS CONTAMINATED AND THE POSSIBILITY OF ANOTHER INVERTED TROUGH
ROTATING WESTWARD FROM THE GULF OF MEXICO CAN COME TO FRUITION.
AMPLE MONSOON MOISTURE WILL STILL BE IN PLACE SUCH THAT AREAWIDE
SLIGHT CHANCE TO CHANCE POPS ARE STILL WARRANTED...THOUGH THE TREND
WAS TO TEMPER POPS SOMEWHAT. AS THE WEST TEXAS SUBTROPICAL HIGH
BEGINS TO STRENGTHEN...EXPAND...AND RETROGRADE WESTWARD...THERE
SHOULD BE A GRADUAL DECREASE IN MOISTURE OVER THE WEEKEND
NECESSITATING LOWER PRECIPITATION CHANCES IN THE FORECAST. AS THE
MOISTURE DECREASES...TEMPERATURES WILL REBOUND WITH HIGHS RETURNING
TO ABOVE NORMAL LEVELS.
MEDIUM RANGE MODELS ARE IN VERY GOOD AGREEMENT DEPICTING A VERY WELL
DEFINED INVERTED TROUGH/CIRCULATION CENTER HEADED DIRECTLY TOWARDS
ARIZONA EARLY NEXT WEEK. MOISTURE WILL LIKELY SURGE BACK NORTH INTO
THE REGION AHEAD OF THIS SYSTEM...WHILE DYNAMIC SUPPORT INCREASES.
THIS COULD VERY WELL SIGNAL THE START OF ANOTHER MULTI-DAY ACTIVE
PERIOD...AND HAVE STARTED TRENDING DAYTIME TEMPERATURES LOWER AND
POPS HIGHER.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX...KIWA AND KSDL...
FAIRLY STRONG WESTERLY LOW LEVEL FLOW HAS PERSISTED OVERNIGHT
KEEPING DRAINAGE WINDS AT BAY...AND WILL LIKELY CONTINUE TO DO SO
FOR THE REST OF THIS MORNING. BY THE LATE AFTERNOON...WESTERLY WINDS
ARE EXPECTED TO INCREASE WITH GUSTS AROUND 20 KTS. THIS EVENING
COULD BRING SCATTERED TO POSSIBLY WIDESPREAD SHOWER AND THUNDERSTORM
ACTIVITY...POTENTIALLY LASTING INTO THE OVERNIGHT HOURS. SOME
THUNDERSTORMS COULD BE STRONG...AND CAN/T RULE OUT THE CHANCE OF
STRONG WIND GUSTS AND BLOWING DUST AFFECTING AREA TAF SITES.
CONFIDENCE IN TIMING AND EVOLUTION OF THIS EVENT IS SOMEWHAT ON THE
LOW SIDE...BUT IT IS LOOKING LIKE THIS WILL BE THE FIRST MAJOR
MONSOON DAY FOR THE LOWER DESERTS SO FAR THIS SUMMER.
SOUTHEAST CA AND SOUTHWEST AZ...INCLUDING KIPL AND KBLH...
BROKEN HIGH CLOUDS WILL PERSIST THROUGH THE MORNING HOURS ALONG WITH
CONTINUED BREEZY SOUTHERLY WINDS. EXPECTING VERY SLIM STORM/RAIN
CHANCES FOR THE TAF PERIOD...HOWEVER BREEZY OUTFLOW WINDS AND
ACCOMPANYING DUST MAY MOVE INTO THE REGION STARTING THIS EVENING
FROM STORMS OVER ARIZONA AND NORTHERN MEXICO.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
FRIDAY THROUGH TUESDAY...
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...KUHLMAN
FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
335 AM MST WED JUL 10 2013
.SYNOPSIS...
A MUCH MORE FAVORABLE SOUTHEASTERLY FLOW WILL CONTINUE TO IMPORT
DEEPER MONSOON MOISTURE INTO THE REGION OVER THE NEXT COUPLE DAYS.
THIS WILL LEAD TO AN APPRECIABLE INCREASE IN SHOWERS AND
THUNDERSTORMS ACROSS THE ENTIRE AREA THAT WILL LAST 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...HOWEVER A RETURN TO AN ACTIVE MONSOON PERIOD IS LIKELY
AGAIN EARLY NEXT WEEK.
&&
.DISCUSSION...
A PARADE OF INVERTED TROUGHS/CIRCULATION CENTERS CONTINUES TO MARCH
WESTWARD ALONG THE SOUTHERN PERIPHERY OF THE SUBTROPICAL HIGH
CENTERED OVER WEST TEXAS THIS MORNING. THE MOST IMPRESSIVE WAVE NEAR
28N 108W HAS SUPPORTED AN IMPRESSIVE MCS OVER NORTHERN MEXICO
FEEDING ON MUCAPES OVER 1000 J/KG AND PWATS EXCEEDING 2.0 INCHES.
CLOUDS TOPS HAVE RAPIDLY WARMED IN THE PAST HOUR WITH A NOTABLE
RAPID DECREASE IN LIGHTNING ACTIVITY...SIGNALING A DOWNTREND IN
CONVECTIVE STRENGTH. NEVERTHELESS...OUTFLOWS...GRAVITY WAVES...AND
INFUSION/ADVECTION OF MOISTURE INTO THE MID LEVELS HAS ALLOWED
SHOWERS TO DEVELOP OVER PARTS OF CENTRAL AND SOUTHWEST ARIZONA
OVERNIGHT. SOME STRONGER WIND GUSTS HAVE ALSO BEEN OBSERVED WITH
THIS ACTIVITY BEHIND OUTFLOW BOUNDARIES...AND EXPECTING THIS TREND
WILL CONTINUE FOR THE NEXT SEVERAL HOURS BEFORE THE ENTIRE SYSTEM
DECAYS. RECENT HRRR OUTPUT HAS BEST CAPTURED RADAR TRENDS...AND HAVE
TAILORED SLIGHT CHANCE SHOWER POPS BASED IN ITS OUTPUT THROUGH THE
MID MORNING AS ACTIVITY WANES.
SEVERAL FACETS OF THE FORECAST SUGGEST LATE THIS AFTERNOON...AND
PARTICULARLY THIS EVENING AND OVERNIGHT WILL BECOME QUITE ACTIVE
OVER MUCH OF THE FORECAST AREA. FIRST...THE PRESENCE OF THE SONORAN
INVERTED TROUGH SHOULD PROVIDE AMPLE DIFLUENCE ALOFT SUPPORTIVE FOR
CONVECTIVE SUSTENANCE. SECOND...A TONGUE OF RICH MOISTURE SHOULD BE
ADVECTED NORTHWEST THROUGHOUT THE DAY...AS EVIDENCED BY OBJECTIVE
ANALYSIS OF +10C H7 DEWPOINTS AND +15C H8 DEWPOINTS LURKING IN
SOUTHEAST ARIZONA (TRANSLATING TO DEEP 11-12 G/KG MIXING RATIOS).
THERE IS ALSO SLIGHTLY COOLER TEMPERATURES IN THIS LAYER WHICH WILL
GRADUALLY ERODE THE CAPPING INVERSION NEAR THE H7 LAYER. FORECAST
SOUNDINGS INDICATE INSTABILITY BECOMING MAXIMIZED AOA 750 J/KG
DURING PEAK HEATING WITH INHIBITION SLOWLY ERODING.
HRRR AND HIGH RESOLUTION WRF NMM CORES (AND TO SOME EXTENT THE
COARSER GFS) ARE IN GENERAL AGREEMENT OF A MORE CLASSIC MONSOON
PATTERN OF CONVERGENT CONVECTIVE COMPLEXES FROM BOTH THE MOGOLLON
RIM AND SERN ARIZONA PROGRESSING THROUGH LOWER ELEVATIONS WESTWARD
TO THE COLORADO RIVER VALLEY THROUGHOUT THE EVENING AND OVERNIGHT.
ON THE OTHER HAND...ARW CORES AND THE ECMWF ARE NOT AS BULLISH WITH
THE MAINTENANCE OF CONVECTION TONIGHT. REGARDLESS...CONCEPTUALLY THE
CURRENT PATTERN FAVORS AT LEAST A PARTIALLY ACTIVE DAY...IF NOT VERY
ACTIVE...THOUGH ENOUGH UNCERTAINTY EXISTS TO PRECLUDE UNUSUALLY HIGH
POPS. ANY STRONGER THUNDERSTORM WILL INITIALLY HAVE THE POSSIBILITY
OF PRODUCING SEVERE WIND GUSTS AND DENSE BLOWING DUST AS T/TD
SPREADS WILL BE ABOVE 40F...THOUGH AS ACTIVITY EVOLVES OVERNIGHT AND
THE ATMOSPHERIC PROFILE BECOME MORE MOIST...THE THREAT SHOULD
TRANSITION TO MORE OF A HEAVY RAIN THREAT (THOUGH STRONGER WINDS
STILL CANNOT BE DISCOUNTED).
LARGE UNCERTAINTY EXISTS REGARDING THE PROCESSION OF TEMPERATURES
AND CONVECTIVE THREAT THURSDAY...PRIMARILY DEPENDENT ON THE
ANTECEDENT CONDITIONS AND ACTIVITY WEDNESDAY NIGHT. SOME MODEL
FORECASTS SUGGEST THURSDAY MAY BE ONE OF THOSE RARE SUMMER DAYS
SOCKED IN WITH CLOUDS...UNUSUALLY COOL TEMPERATURES...AND LITTLE
AVAILABLE INSTABILITY. HOWEVER...IF CLOUDS BEGIN TO CLEAR DURING
PEAK HEATING IT WILL TAKE ONLY A FEW HOURS TO REALIZE MLCAPES ABOVE
1000 J/KG COINCIDENT WITH AMPLE SHEAR AND MOISTURE PROFILES. KEPT
POPS GENERALLY IN THE 30 PERCENT CHANCE CATEGORY GIVEN THE OVERALL
LOW CONFIDENCE FORECAST...THOUGH IF ORGANIZED CONVECTION DOES FORM
IMPACTS COULD BE SIGNIFICANT. REGARDLESS...IT APPEARS TEMPERATURES
WILL STAY IN A BELOW NORMAL CATEGORY (WHETHER A FEW DEGREES OR 10+
DEGREES BELOW REMAINS TO BE SEEN).
FRIDAY COULD BE A SLOWER CONVECTIVE DAY IF THURSDAY ENDS UP BEING AN
ACTIVE MONSOON DAY...OR VICE VERSA COULD BE ACTIVE IF THURSDAY
REMAINS CONTAMINATED AND THE POSSIBILITY OF ANOTHER INVERTED TROUGH
ROTATING WESTWARD FROM THE GULF OF MEXICO CAN COME TO FRUITION.
AMPLE MONSOON MOISTURE WILL STILL BE IN PLACE SUCH THAT AREAWIDE
SLIGHT CHANCE TO CHANCE POPS ARE STILL WARRANTED...THOUGH THE TREND
WAS TO TEMPER POPS SOMEWHAT. AS THE WEST TEXAS SUBTROPICAL HIGH
BEGINS TO STRENGTHEN...EXPAND...AND RETROGRADE WESTWARD...THERE
SHOULD BE A GRADUAL DECREASE IN MOISTURE OVER THE WEEKEND
NECESSITATING LOWER PRECIPITATION CHANCES IN THE FORECAST. AS THE
MOISTURE DECREASES...TEMPERATURES WILL REBOUND WITH HIGHS RETURNING
TO ABOVE NORMAL LEVELS.
MEDIUM RANGE MODELS ARE IN VERY GOOD AGREEMENT DEPICTING A VERY WELL
DEFINED INVERTED TROUGH/CIRCULATION CENTER HEADED DIRECTLY TOWARDS
ARIZONA EARLY NEXT WEEK. MOISTURE WILL LIKELY SURGE BACK NORTH INTO
THE REGION AHEAD OF THIS SYSTEM...WHILE DYNAMIC SUPPORT INCREASES.
THIS COULD VERY WELL SIGNAL THE START OF ANOTHER MULTI-DAY ACTIVE
PERIOD...AND HAVE STARTED TRENDING DAYTIME TEMPERATURES LOWER AND
POPS HIGHER.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX...KIWA AND KSDL...
ELEVATED WESTERLY SURFACE FLOW WILL PERSIST FOR THE PHX TERMINALS
THROUGH MUCH OF THE EVENING AND EARLY MORNING HOURS. LARGE AREA OF
STORM ACTIVITY WELL TO OUR SOUTH ALONG THE INTL BORDER MAY SEND
BREEZY SOUTH WINDS...POTENTIAL FOR LOFTED DUST AND DEBRIS CLOUDS TO
THE REGION BY THE SUNRISE. CONFIDENCE AT THIS TIME IS TOO LOW TO
INCLUDE ANY WIND HEADING CHANGES OR CIGS BELOW 10K AGL IN THE 06Z
TAF PACKAGE. STRAY SHOWER DEVELOPMENT ACROSS THE METRO COULD OCCUR
OVERNIGHT...MOSTLY REMAINING HIGH BASED WITH LITTLE MEASURABLE
PRECIP BUT POTENTIAL FOR BREEZY BUT ERRATIC WINDS IN THE VICINITY OF
THE TERMINALS.
SOUTHEAST CA AND SOUTHWEST AZ...INCLUDING KIPL AND KBLH...
SCT-BKN HIGH CLOUDS WILL PERSIST OVERNIGHT AS WILL CONTINUED BREEZY
SOUTHEASTERLY WINDS. VERY SLIM STORM/RAIN CHANCES CONTINUE TO REMAIN
FOR THE TAF PERIOD...HOWEVER BREEZY OUTFLOW WINDS AND ACCOMPANYING
DUST MAY MOVE INTO THE REGION FROM MEXICO AND THE GULF OF CALIFORNIA
IN THE EARLY MORNING HOURS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
THURSDAY THROUGH MONDAY...
THERE WILL BE AN INCREASED LIKELIHOOD OF MAINLY AFTERNOON AND
EVENING SHOWERS AND THUNDERSTORMS...AS MOISTURE INCREASES ACROSS THE
FORECAST AREA. THIS WILL ALSO MEAN INCREASED HUMIDITY...WITH
AFTERNOON MINIMUM VALUES GENERALLY ONLY DROPPING INTO THE 20-30
PERCENT RANGE. OVERNIGHT RECOVERY SHOULD BE GOOD TO EXCELLENT WITH
READINGS CLIMBING ABOVE 40 PERCENT MOST NIGHTS. SOME DRYING IS
EXPECTED SUNDAY INTO MONDAY. 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...MCLANE/LEINS
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
1130 PM PDT TUE JUL 9 2013
.SYNOPSIS...
MONSOONAL MOISTURE WILL GRADUALLY INCREASE THROUGH WEDNESDAY WITH A
GREATER INFLUX ON WEDNESDAY NIGHT AND THURSDAY. SLOW DRYING FROM
FRIDAY THROUGH MONDAY WITH ANOTHER BIGGER INFLUX OF MONSOONAL
MOISTURE POSSIBLE AROUND THE MIDDLE OF NEXT WEEK. A FEW SPRINKLES
ARE POSSIBLE TONIGHT INTO WEDNESDAY MORNING WITH A SLIGHT CHANCE OF
SHOWERS AND THUNDERSTORMS OVER THE MOUNTAINS WEDNESDAY AFTERNOON.
THE INCREASING MOISTURE ON WEDNESDAY NIGHT AND THURSDAY WILL BRING
COOLER DAYTIME TEMPERATURES AND GREATER CHANCES FOR SHOWERS AND
THUNDERSTORMS. A SLIGHT CHANCE OF AFTERNOON THUNDERSTORMS FOR THE
MOUNTAINS AND DESERTS WILL CONTINUE ON FRIDAY THROUGH THE WEEKEND
WITH GRADUAL INLAND WARMING.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
UPDATE FOR THE REST OF TONIGHT INTO WEDNESDAY MORNING TO ACCOUNT FOR
SATELLITE AND RADAR TRENDS AND RELATED HRRR FORECASTS THAT SHOW
ELEVATED CONVECTION DEVELOPING OVER SAN DIEGO COUNTY LATE THIS
EVENING...THEN SPREADING NORTHWESTWARD OVERNIGHT INTO WEDNESDAY
MORNING. THIS WOULD MOST LIKELY BRING SOME SPRINKLES OR VERY LIGHT
MEASURABLE AMOUNTS.
PREVIOUS DISCUSSION...
WATER VAPOR IMAGERY CONTINUES TO SHOW HIGH PRESSURE CENTERED OVER
THE FOUR CORNERS THIS EVENING...EXTENDING BACK TOWARDS SOUTHERN
CALIFORNIA. SUBTROPICAL MOISTURE IS ROTATING AROUND THIS HIGH...AND
SPREADING INTO SOUTHERN CALIFORNIA...MAKING FOR A NICE SUNSET THIS
EVENING. THE 00Z KNKX SOUNDING SHOWS THAT PRECIPITABLE WATER VALUES
ARE UP TO 1.26 INCHES...BUT THIS MOISTURE IS STILL AT OR WELL ABOVE
600 MBS...WITH A VERY DRY LAYER BELOW 600 MBS. THAT BEING
SAID...ONE SHOWER DID DEVELOP THIS AFTERNOON OVER SANTA ROSA
MOUNTAIN...PRODUCING A DECENT LITTLE RAIN SHOWER. THE RADAR IS NOW
QUIET...WITH TEMPERATURES WITHIN A FEW DEGREES OF THIS TIME LAST
NIGHT. THE MOST NOTICEABLE DIFFERENCES AT THIS TIME THOUGH ARE WITH
THE HIGH CLOUDS SPREADING ACROSS THE REGION AND THE SURGE OF HIGHER
DEW POINTS IN THE SOUTHERN DESERTS. IN FACT...THERMAL IS CURRENTLY
89 OVER 75...MAKING FOR A VERY MUGGY EVENING. NEEDLESS TO SAY...IT
WILL LIKELY BE ANOTHER WARM NIGHT IN THESE AREAS.
THE SUBTROPICAL MOISTURE WILL CONTINUE TO SPREAD INTO SOUTHERN
CALIFORNIA THROUGH WEDNESDAY...WITH A GRADUAL COOLING TREND
POSSIBLE. HOWEVER...HUMIDITY VALUES WILL BE ON THE RISE...MAKING IT
FEEL VERY MUGGY ACROSS THE SOUTHLAND. AT THIS TIME...THE LATEST
MODELS CONTINUE TO SHOW THAT THE BRUNT OF THE MOISTURE WILL REMAIN
ABOVE 600 MBS THROUGH TOMORROW...WITH JUST A FEW ISOLATED AFTERNOON
SHOWERS OR THUNDERSTORMS POSSIBLE OVER THE MOUNTAINS. THAT BEING
SAID...THE BETTER THREAT OF SHOWERS AND THUNDERSTORMS WILL DEVELOP
LATE WEDNESDAY NIGHT INTO THURSDAY...AS A EASTERLY WAVE MOVING
ACROSS CHIHUAHUA...ROUNDS THE RIDGE CORNER AND LIFTS ACROSS SOUTHERN
CALIFORNIA. AS THIS DISTURBANCE MOVES ACROSS THE REGION...THE
VALLEYS AND POTENTIALLY THE COASTAL AREAS MAY ALSO SEE A FEW SHOWERS
AND THUNDERSTORMS. PRECIPITABLE WATER VALUES WILL BE WELL OVER 1.5
INCHES ACROSS THE SOUTHLAND...AND APPROACH 1.8 IN THE SOUTHERN
DESERTS. THEREFORE...THINK THAT THE THREAT OF FLASH FLOODING WILL
ALSO DEVELOP DURING THE DAY ON THURSDAY...ESPECIALLY FOR THE
MOUNTAINS AND DESERTS.
THE THREAT OF SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH THE
WEEKEND...BUT WILL BE MORE THE MORE TYPICAL SUMMER DIURNAL TYPE
THUNDERSTORMS. DRIER CONDITIONS WILL DEVELOP BY MONDAY...BUT
ANOTHER SURGE OF SUBTROPICAL MOISTURE WILL HEAD THIS WAY FOR MID
WEEK.
&&
.AVIATION...
100410Z...COAST/VALLEYS...AREAS OF STRATUS WILL DEVELOP ALONG THE
COAST...MAINLY BETWEEN 06Z AND 09Z AND SPREAD 10-15 MI INLAND BY
12Z. BASES WILL BE 700-1000 FT MSL WITH TOPS TO 1200 FT MSL. STRATUS
WILL PROBABLY REACH KSNA LATE TONIGHT...UNLIKE THE PAST 2 NIGHTS.
STRATUS WILL MOSTLY DISSIPATE AROUND 16-17Z WED. STRATUS WILL HAVE
LESS COVERAGE WED NIGHT. OTHERWISE...MOSTLY BKN CLOUDS ABOVE 13000
FT MSL WILL PREVAIL THROUGH WED NIGHT.
MTNS/DESERTS...BKN CLOUDS ABOVE 13000 FT MSL WILL PREVAIL THROUGH
WED NIGHT. AREAS OF CU/TCU WITH BASES 8000-9000 FT MSL WILL DEVELOP
AGAIN WED AFTERNOON...AND ISOLATED TSTORMS WILL BE POSSIBLE WITH
TOPS TO 35000 FT MSL.
&&
.MARINE...
2.5 FOOT/15 SECOND SWELL FROM 180 DEG WILL CONTINUE THROUGH
WED...THEN A LONG-PERIOD SWELL FROM 170 DEG WILL BUILD WED
NIGHT/EARLY THU. THE SWELL WILL INITIALLY HAVE A PERIOD OF AROUND 20
SECONDS BUT A HEIGHT OF ONLY 2 FEET...THEN THU/FRI THE HEIGHT WILL
BE 3-4 FEET BUT WITH A PERIOD SHORTENING TO 15-17 SECONDS. GIVEN THE
STEEP ANGLE TO THE COAST...MOST OF THE ENERGY WILL BYPASS SAN DIEGO
COUNTY...EXCEPT MAINLY NORTH OF CARLSBAD AND NEAR PT LOMA. IN ORANGE
COUNTY...THE ANGLE WILL RESULT IN ABOUT 60 PERCENT OF THE ENERGY
AVAILABLE FOR THE WAVES...SO 4-6 FOOT SURF WITH LOCAL SETS AROUND 8
FEET ARE LIKELY THU/FRI. LONG SHORE CURRENTS WILL DEVELOP...ALONG
WITH THE TYPICAL STRONG RIP CURRENTS WITH THESE WAVE HEIGHTS.
ANOTHER SSW SWELL WILL ARRIVE SAT TO KEEP SURF ABOVE NORMAL ALONG
S-FACING BEACHES.
&&
.FIRE WEATHER...
SUBTROPICAL MOISTURE WILL CONTINUE TO SPREAD ACROSS SOUTHERN
CALIFORNIA THE NEXT FEW DAYS...WITH COOLER CONDITIONS DEVELOPING AND
HUMIDITY VALUES GRADUALLY IMPROVING. THERE WILL BE A SLIGHT CHANCE
OF AFTERNOON SHOWERS AND THUNDERSTORMS ON WEDNESDAY...WITH A BETTER
CHANCE FOR SHOWERS AND THUNDERSTORMS WEDNESDAY NIGHT AND THURSDAY.
AS THE LOWER ATMOSPHERE MOISTENS...THE CHANCE OF WETTING RAINS WILL
IMPROVE AS WELL...WITH ISOLATED FLASH FLOODING POSSIBLE BY THURSDAY.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...BEACH HAZARDS STATEMENT THROUGH LATE SATURDAY NIGHT FOR THE
BEACHES IN THE ORANGE COUNTY COASTAL AREAS.
BEACH HAZARDS STATEMENT FROM LATE WEDNESDAY NIGHT THROUGH LATE
SATURDAY NIGHT FOR THE SAN DIEGO COUNTY COASTAL AREAS.
PZ...NONE.
&&
$$
UPDATE...17
SYNOPSIS...BA
PUBLIC/FIRE...PALMER
AVIATION/MARINE...MAXWELL
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1103 AM MDT WED JUL 10 2013
.UPDATE...INGREDIENTS LOOK TO BE COMING TOGETHER FOR AN AFTERNOON
OF STRONG STORMS OVER NORTHEAST COLORADO. MOIST EASTERLY FLOW WILL
CONTINUE BRINGING LOW LEVEL MOISTURE INTO THE AREA. STRONG SOLAR
HEATING WILL WARM THE AIRMASS THROUGH MID-AFTERNOON. A SIGNIFICANT
BOUNDARY MAY SET UP ACROSS WASHINGTON...MORGAN AND EASTERN WELD
COUNTIES...FROM RAIN THAT FELL OVER THE NEBRASKA PANHANDLE AROUND
SUNRISE. AN UPPER LEVEL DISTURBANCE IS EXPECTED TO MOVE OUT OF THE
MOUNTAINS DURING THE AFTERNOON WHICH SHOULD HELP ORGANIZE
CONVECTIVE ACTIVITY THAT DEVELOPS. MODEL CAPE FORECASTS SHOW 3000+
J/KG ON THE NORTHEAST PLAINS LATER THIS AFTERNOON.
WILL BE UPDATING THE ZONES TO INCREASE POPS TO 50 PERCENT ACROSS
THE PLAINS THIS AFTERNOON. WILL ALSO MENTION THUNDERSTORMS
CAPABLE OF PRODUCING LARGE HAIL AND DAMAGING WIND.
&&
.AVIATION...SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP DURING
THE AFTERNOON HOURS AND IMPACT KDEN AS WELL AS THE ARRIVAL AND
DEPARTURE GATES. SEVERE WEATHER WITH LARGE HAIL AND STRONG
STRAIGHTLINE WINDS WILL BE POSSIBLE TO THE EAST AND NORTHEAST OF
OF DENVER. SOUTHEAST AND EASTERLY WINDS ARE EXPECTED DURING THE
EARLY AFTERNOON AHEAD OF INITIAL THUNDERSTORM DEVELOPMENT. LATER
IN THE AFTERNOON AND EVENING...WINDS WILL PROBABLY BE OUT OF THE
NORTH AND NORTHEAST DUE TO OUTFLOW WINDS FROM STRONG SHOWERS ON
THE NORTHEAST COLORADO PLAINS. THUNDERSTORM ACTIVITY COULD REMAIN
IN THE KDEN VICINITY THROUGH 7 PM.
&&
.HYDROLOGY...SCATTERED THUNDERSTORMS ARE EXPECTED FROM THE HIGHER
TERRAIN EASTWARD. SHOWERS OVER THE MOUNTAINS WILL HAVE FORWARD
MOTIONS OF 10-20 MPH...REDUCING THE THREAT OF HEAVY RAINFALL
AMOUNTS OVER THE BURN AREAS. ON THE PLAINS...THUNDERSTORMS THAT
DEVELOP ON BOUNDARIES MAY BE SLOWER MOVING AND CAPABLE OF
PRODUCING RAIN AMOUNTS UP TO ONE INCH IN LESS THAN 45 MINUTES.
LOCALIZED FLOODING WILL BE POSSIBLE.
&&
.PREV DISCUSSION... /ISSUED 344 AM MDT WED JUL 10 2013/
SHORT TERM...AN UPPER LEVEL HIGH WILL REMAIN OVER THE SRN ROCKIES
WITH MDT WNW FLOW ALOFT ACROSS NRN CO. AT THE SFC LOW PRES WILL BE
OVER THE MTNS AS SFC HIGH PRES IS OVER THE CNTRL US. THUS ALLOWS
FOR INCREASING SELY LOW LVL FLOW EAST OF THE MTNS BY AFTN INTO
TONIGHT.
CURRENTLY LOW LVL MOISTURE HAS INCREASED BEHIND WEAK COOL FNT
ACROSS MOST OF THE PLAINS AS A WEAK DENVER CYCLONE HAS DEVELOPED.
MEANWHILE AN UPPER LEVEL JET IS POSITIONED OVER THE FAR NERN
CORNER WHICH HAS BEEN ALLOWING FOR SCT SHOWERS EARLY THIS MORNING.
FOR THIS AFTN MOST OF THE SHORT RANGE MODELS SHOW S TO SE LOW LVL
FLOW EAST OF THE MTNS WITH NO HINTS OF A DENVER CYCLONE EXCEPT FOR
THE WRF WHICH KEEPS IT INTACT. IF THE CYCLONE STAYS INTACT THEN A
CONVERGENCE ZONE WILL SET UP ALONG THE FRONT RANGE AND BE A FOCUS
FOR TSTM DEVELOPMENT. IF THE CYCLONE IS WIPED OUT THEN CONVECTIVE
DEVELOPMENT WILL HAVE TO RELY ON OUTFLOW BOUNDARIES FROM TSTMS
OVER THE HIGHER TERRAIN WHICH COULD KEEP BEST CHC OF TSTMS EAST OF
THE URBAN CORRIDOR. FOR NOW THERE IS TOO MUCH UNCERTAINTY TO
MONKEY AROUND WITH THE CURRENT CHC POPS SO WILL JUST LEAVE AS IS.
SFC BASED CAPES BY AFTN DEPENDING ON HOW MUCH MIXING OCCURS LOOK
TO BE AROUND 1000-1500 J/KG ALONG THE FRONT RANGE TO NEAR 3000
J/KG OVER THE NERN PLAINS. WITH WNW MID LVL FLOW IN THE 25-30 KT
RANGE SHEAR WILL BE FAVORABLE FOR A FEW SVR STORMS ESPECIALLY
WHERE THE HIGHER CAPES RESIDE OVER THE PLAINS WITH LARGE HAIL AND
STRONG WINDS AND POSSIBLY A TORNADO. AS FOR HIGHS THIS AFTN IF YOU
BELIEVE THE HRRR AND RAP READINGS ALONG THE FRONT RANGE WILL BE
JUST AS HOT AS YESTERDAY WHILE READINGS OVER THE NERN PLAINS WILL
BE MAINLY IN THE UPPER 80S TO AROUND 90. FOR NOW WILL KEEP
READINGS IN THE UPPER 80S TO LOWER 90S WITH THE WARMEST VALUES
CLOSER TO THE FOOTHILLS. NATURALLY IF THE HRRR AND RAP ARE RIGHT
MY HIGHS WILL BE OFF BY AROUND 5 DEGREES OVER THE URBAN CORRIDOR.
FOR TONIGHT THE TSTMS OVER THE PLAINS SHOULD GRADUALLY DEVELOP
INTO AN MCS AND MOVE ESE OUT OF THE AREA BY AROUND MIDNIGHT. ONCE
AGAIN COULD SEE A FEW SVR STORMS OVER THE PLAINS DURING THE EARLY
EVENING HOURS. WITH HIGH PRECIPITABLE VALUES SOME AREAS OVER THE
PLAINS COULD SEE QUITE A BIT OF RAINFALL. IN THE MTNS AND
FOOTHILLS TSTM CHANCES SHOULD MOSTLY END BY 00Z.
LONG TERM...BY THURSDAY...MODEL CONSENSUS INDICATES THE 500MB RIDGE
AXIS ALIGNED WITH THE SPINE OF THE COLORADO/NEW MEXICO ROCKIES WHICH
PLACES NORTHEAST COLORADO UNDER A LIGHT NORTHWESTERLY FLOW ALOFT.
THIS FLOW DOES LITTLE TO COOL TEMPERATURES ON THURSDAY. MATTER OF
FACT...700 MB TEMPERATURES WARM A FEW DEGS C FOLLOWING THE SLIGHT
POST-FRONTAL COOL DOWN ON WEDNESDAY. SHOULD SEE LOW/MID 90S FOR
AFTERNOON READINGS ON THE PLAINS...LOW-MID 80S IN THE MTN VALLEYS
AND 60S-70S FOR HIGH TEMPS AT HIGHER ELEVATIONS. STRONG SUBSIDENCE
INVERSION AT MID-LEVELS AND LOWER PRECIPITABLE WATER VALUES SHOULD
SIGNIFICANTLY REDUCE THE CHANCE OF T-STORMS ON THURSDAY...
PARTICULARLY EAST OF THE MOUNTAINS. ALTHOUGH MODELS SHOW LOW/MID-
LEVEL MOISTURE CREEPING UP ON THE PLAINS LATE IN THE DAY WITH
INCREASING SOUTHERLY LOW-LEVEL FLOW. COULD SEE ISOLATED T-STORMS
FORMING ALONG THE FRONT RANGE BY LATE AFTERNOON AND/OR EARLY
EVENING...THEN DRIFTING NORTHEASTWARD OVER THE NEARBY PLAINS WHERE
THEY SHOULD DIE A QUICK DEATH WITH A STRONG CAP IN PLACE.
ON FRIDAY...MODELS SHOW THE UPPER RIDGE POSITIONED OVER THE ROCKY
MOUNTAIN REGION UNDERGOING A POSITIVE TILT AS IT MIGRATES SLOWLY
OVER THE WESTERN GREAT PLAINS. THE TILT RESULTS IN A SHIFT TO
SOUTHWEST FLOW ALOFT OVER COLORADO WHICH THEN BEGINS TO ADVECT
MOISTURE LADEN SUBTROPICAL AIR UP FROM THE DESERT SOUTHWEST. AT THE
CORE OF THE 700-500 MB MOISTURE PLUME ARE 6-8 G/KG SPECIFIC
HUMIDITIES...WHICH MODELS SHOW SPREADING NORTHWARD OVER WESTERN
COLORADO THROUGH THE DAY. BY LATE ON FRIDAY WITH THE 700-500MB HIGH
CENTERED OVER SOUTH-CENTRAL KANSAS/NORTH-CENTRAL OKLAHOMA...THIS
PLUME OF MOIST SUBTROPICAL AIR ADVANCES EASTWARD OVER EASTERN
COLORADO WHERE IT AIDS IN THUNDERSTORM DEVELOPMENT. BY LATE
AFTERNOON...COMPUTED SFC BASED CAPES UP AROUND 1500 J/KG ON THE
PLAINS AND MARGINAL SHEAR...MAY SEE ONE OR TWO LATE DAY STORMS
BECOME SEVERE...BUT WELL EAST OF THE I-25 URBAN CORRIDOR. THERE/S A
GREATER RISK FOR LOCALLY HEAVY RAINFALL FROM SLOW MOVING T-STORMS
FORMING ALONG OUTFLOW BOUNDARIES. WILL NEED TO CLOSELY MONITOR
RECENT BURN SCARS AS LESS THAN A HALF INCH OF RAIN IN A SHORT PERIOD
OF TIME COULD CAUSE HEAVY RUNOFF PROBLEMS. TEMPERATURES ON FRIDAY
ABOUT THE SAME AS THOSE ON THURSDAY...BUT PROBABLY OCCURRING EARLIER
IN THE DAY BEFORE THE ANTICIPATED CLOUD BUILDUP.SHOWERS/STORMS
EXPECTED TO LINGERING INTO THE EVENING HOURS WITH THE AXIS OF THE
PLUME BISECTING THE FCST AREA FROM SOUTHWEST-TO-NORTHEAST. STORM
INTENSITY SHOULD BE LOW...WHILE THE POTENTIAL FOR LOCALLY HEAVY RAIN
WILL STILL EXIST.
OVER THE WEEKEND...THE UPPER RIDGE GOES THROUGH SOME CHANGES AS IT
SPLITS INTO TWO PIECES...ONE PART MIGRATING ACROSS THE UPPER
MIDWEST...WHILE THE OTHER PART GAINING STRENGTH NEAR THE FOUR
CORNERS. THIS INITIALLY THINS OUT THE PLUME OF SUBTROPICAL MOISTURE
STREAMING OVER COLORADO. HOWEVER BY LATE ON SATURDAY THE MONSOONAL
FLOW OF MOIST AIR RESUMES...RESULTING IN ANOTHER ROUND OF SCATTERED
SHOWERS/T-STORMS SATURDAY AFTERNOON AND EVENING...SOME POSSIBLY
PRODUCING LOCALLY HEAVY RAINFALL. HOWEVER STORM DEVELOPMENT ON
SUNDAY APPEARS TO CONCENTRATE MORE OVER THE HIGH COUNTRY WITH LOW
LEVELS APPEARING DRIER ON THE PLAINS. TEMPERATURES BOTH DAYS REMAIN
NEAR TO SLIGHTLY ABOVE AVERAGE.
BY MONDAY...THE CORE OF THE SUBTROPICAL MOISTURE PLUME IS PROGGED TO
SHIFT EVEN FARTHER WEST AWAY FROM THE FRONT RANGE WITH THE FLOW
ALOFT BECOMING MORE EAST-SOUTHEASTERLY IN DIRECTION WITH THE UPPER
HIGH OVER THE FOUR CORNERS FALLING APART. THEREFORE CHANCES FOR
PRECIP ON MONDAY APPEAR MUCH LOWER ESPLY EAST OF THE MTNS. MODELS
ALSO INDICATE SLIGHTLY COOLER TEMPERATURES ON MONDAY. NOT QUITE SURE
WHY...POSSIBLY DUE TO GREAT CLOUD COVER. BY TUESDAY...THE HIGHEST
SPECIFIC HUMIDITIES REMAIN WEST OF THE CONTINENTAL DIVIDE AS
STEERING WINDS ALOFT TURN MORE SOUTHERLY DURING THE DAY. WILL WILL
HELP TO INCREASE TEMPERATURES PARTICULARLY ON THE PLAINS.
AVIATION...A WEAK DENVER CYCLONE HAS DEVELOPED OVER DIA EARLY
THIS MORNING. AS MENTIONED ABV MOST OF THE SHORT RANGE MODELS WIPE
IT OUT BY MIDDAY WITH RATHER STG SSE LOW LVL DEVELOPING. THE WRF
IS THE ONLY MODEL WHICH KEEPS THE CYCLONE INTACT THRU THE AFTN
WHICH LEADS TO VARYING WIND DIRECTIONS DEPENDING ON WHERE IT
RESIDES. FOR NOW WILL KEEP WINDS SSE THRU THE AFTN. LATEST DATA
SUGGEST TSTMS COULD DVLP AS EARLY AS 19Z AND THEN MOVE EAST OF THE
AIRPORT BY 23Z. ITS ENTIRELY POSSIBLE IF THE DENVER CYCLONE GETS
WIPED OUT THAT TSTMS MAY NOT AFFECT THE AIRPORT AT ALL AS THEY
FOCUS TO THE EAST AND SOUTH HOWEVER WILL KEEP A PROB GROUP IN THE
TAF. IF A STRONGER STORM WERE TO AFFECT THE AIRPORT THEN MAY SEE
BRIEF MVFR CONDITIONS IN THE 19Z-23Z TIMEFRAME.
BY THIS EVENING IT LOOKS LIKE THE TSTM THREAT WILL REMAIN TO THE
EAST OF THE AIRPORT. RIGHT NOW THE MODELS SHOW EITHER A SLY OR
SELY COMPONENT FOR WINDS WHICH BECOME MORE SSW AFTER 06Z.
HYDROLOGY...SCATTERED THUNDERSTORMS WILL DEVELOP BY EARLY AFTN.
POTENTIAL RAINFALL AMOUNTS IN THE BURN AREAS WILL BE IN THE 0.25
TO 0.50 RANGE.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...DANKERS
LONG TERM....99
AVIATION...DANKERS
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
344 AM MDT WED JUL 10 2013
.SHORT TERM...AN UPPER LEVEL HIGH WILL REMAIN OVER THE SRN ROCKIES
WITH MDT WNW FLOW ALOFT ACROSS NRN CO. AT THE SFC LOW PRES WILL BE
OVER THE MTNS AS SFC HIGH PRES IS OVER THE CNTRL US. THUS ALLOWS
FOR INCREASING SELY LOW LVL FLOW EAST OF THE MTNS BY AFTN INTO
TONIGHT.
CURRENTLY LOW LVL MOISTURE HAS INCREASED BEHIND WEAK COOL FNT
ACROSS MOST OF THE PLAINS AS A WEAK DENVER CYCLONE HAS DEVELOPED.
MEANWHILE AN UPPER LEVEL JET IS POSITIONED OVER THE FAR NERN
CORNER WHICH HAS BEEN ALLOWING FOR SCT SHOWERS EARLY THIS MORNING.
FOR THIS AFTN MOST OF THE SHORT RANGE MODELS SHOW S TO SE LOW LVL
FLOW EAST OF THE MTNS WITH NO HINTS OF A DENVER CYCLONE EXCEPT FOR
THE WRF WHICH KEEPS IT INTACT. IF THE CYCLONE STAYS INTACT THEN A
CONVERGENCE ZONE WILL SET UP ALONG THE FRONT RANGE AND BE A FOCUS
FOR TSTM DEVELOPMENT. IF THE CYCLONE IS WIPED OUT THEN CONVECTIVE
DEVELOPMENT WILL HAVE TO RELY ON OUTFLOW BOUNDARIES FROM TSTMS
OVER THE HIGHER TERRAIN WHICH COULD KEEP BEST CHC OF TSTMS EAST OF
THE URBAN CORRIDOR. FOR NOW THERE IS TOO MUCH UNCERTAINTY TO
MONKEY AROUND WITH THE CURRENT CHC POPS SO WILL JUST LEAVE AS IS.
SFC BASED CAPES BY AFTN DEPENDING ON HOW MUCH MIXING OCCURS LOOK
TO BE AROUND 1000-1500 J/KG ALONG THE FRONT RANGE TO NEAR 3000
J/KG OVER THE NERN PLAINS. WITH WNW MID LVL FLOW IN THE 25-30 KT
RANGE SHEAR WILL BE FAVORABLE FOR A FEW SVR STORMS ESPECIALLY
WHERE THE HIGHER CAPES RESIDE OVER THE PLAINS WITH LARGE HAIL AND
STRONG WINDS AND POSSIBLY A TORNADO. AS FOR HIGHS THIS AFTN IF YOU
BELIEVE THE HRRR AND RAP READINGS ALONG THE FRONT RANGE WILL BE
JUST AS HOT AS YESTERDAY WHILE READINGS OVER THE NERN PLAINS WILL
BE MAINLY IN THE UPPER 80S TO AROUND 90. FOR NOW WILL KEEP
READINGS IN THE UPPER 80S TO LOWER 90S WITH THE WARMEST VALUES
CLOSER TO THE FOOTHILLS. NATURALLY IF THE HRRR AND RAP ARE RIGHT
MY HIGHS WILL BE OFF BY AROUND 5 DEGREES OVER THE URBAN CORRIDOR.
FOR TONIGHT THE TSTMS OVER THE PLAINS SHOULD GRADUALLY DEVELOP
INTO AN MCS AND MOVE ESE OUT OF THE AREA BY AROUND MIDNIGHT. ONCE
AGAIN COULD SEE A FEW SVR STORMS OVER THE PLAINS DURING THE EARLY
EVENING HOURS. WITH HIGH PRECIPITABLE VALUES SOME AREAS OVER THE
PLAINS COULD SEE QUITE A BIT OF RAINFALL. IN THE MTNS AND
FOOTHILLS TSTM CHANCES SHOULD MOSTLY END BY 00Z.
.LONG TERM...BY THURSDAY...MODEL CONSENSUS INDICATES THE 500MB RIDGE
AXIS ALIGNED WITH THE SPINE OF THE COLORADO/NEW MEXICO ROCKIES WHICH
PLACES NORTHEAST COLORADO UNDER A LIGHT NORTHWESTERLY FLOW ALOFT.
THIS FLOW DOES LITTLE TO COOL TEMPERATURES ON THURSDAY. MATTER OF
FACT...700 MB TEMPERATURES WARM A FEW DEGS C FOLLOWING THE SLIGHT
POST-FRONTAL COOL DOWN ON WEDNESDAY. SHOULD SEE LOW/MID 90S FOR
AFTERNOON READINGS ON THE PLAINS...LOW-MID 80S IN THE MTN VALLEYS
AND 60S-70S FOR HIGH TEMPS AT HIGHER ELEVATIONS. STRONG SUBSIDENCE
INVERSION AT MID-LEVELS AND LOWER PRECIPITABLE WATER VALUES SHOULD
SIGNIFICANTLY REDUCE THE CHANCE OF T-STORMS ON THURSDAY...
PARTICULARLY EAST OF THE MOUNTAINS. ALTHOUGH MODELS SHOW LOW/MID-
LEVEL MOISTURE CREEPING UP ON THE PLAINS LATE IN THE DAY WITH
INCREASING SOUTHERLY LOW-LEVEL FLOW. COULD SEE ISOLATED T-STORMS
FORMING ALONG THE FRONT RANGE BY LATE AFTERNOON AND/OR EARLY
EVENING...THEN DRIFTING NORTHEASTWARD OVER THE NEARBY PLAINS WHERE
THEY SHOULD DIE A QUICK DEATH WITH A STRONG CAP IN PLACE.
ON FRIDAY...MODELS SHOW THE UPPER RIDGE POSITIONED OVER THE ROCKY
MOUNTAIN REGION UNDERGOING A POSITIVE TILT AS IT MIGRATES SLOWLY
OVER THE WESTERN GREAT PLAINS. THE TILT RESULTS IN A SHIFT TO
SOUTHWEST FLOW ALOFT OVER COLORADO WHICH THEN BEGINS TO ADVECT
MOISTURE LADEN SUBTROPICAL AIR UP FROM THE DESERT SOUTHWEST. AT THE
CORE OF THE 700-500 MB MOISTURE PLUME ARE 6-8 G/KG SPECIFIC
HUMIDITIES...WHICH MODELS SHOW SPREADING NORTHWARD OVER WESTERN
COLORADO THROUGH THE DAY. BY LATE ON FRIDAY WITH THE 700-500MB HIGH
CENTERED OVER SOUTH-CENTRAL KANSAS/NORTH-CENTRAL OKLAHOMA...THIS
PLUME OF MOIST SUBTROPICAL AIR ADVANCES EASTWARD OVER EASTERN
COLORADO WHERE IT AIDS IN THUNDERSTORM DEVELOPMENT. BY LATE
AFTERNOON...COMPUTED SFC BASED CAPES UP AROUND 1500 J/KG ON THE
PLAINS AND MARGINAL SHEAR...MAY SEE ONE OR TWO LATE DAY STORMS
BECOME SEVERE...BUT WELL EAST OF THE I-25 URBAN CORRIDOR. THERE/S A
GREATER RISK FOR LOCALLY HEAVY RAINFALL FROM SLOW MOVING T-STORMS
FORMING ALONG OUTFLOW BOUNDARIES. WILL NEED TO CLOSELY MONITOR
RECENT BURN SCARS AS LESS THAN A HALF INCH OF RAIN IN A SHORT PERIOD
OF TIME COULD CAUSE HEAVY RUNOFF PROBLEMS. TEMPERATURES ON FRIDAY
ABOUT THE SAME AS THOSE ON THURSDAY...BUT PROBABLY OCCURRING EARLIER
IN THE DAY BEFORE THE ANTICIPATED CLOUD BUILDUP.SHOWERS/STORMS
EXPECTED TO LINGERING INTO THE EVENING HOURS WITH THE AXIS OF THE
PLUME BISECTING THE FCST AREA FROM SOUTHWEST-TO-NORTHEAST. STORM
INTENSITY SHOULD BE LOW...WHILE THE POTENTIAL FOR LOCALLY HEAVY RAIN
WILL STILL EXIST.
OVER THE WEEKEND...THE UPPER RIDGE GOES THROUGH SOME CHANGES AS IT
SPLITS INTO TWO PIECES...ONE PART MIGRATING ACROSS THE UPPER
MIDWEST...WHILE THE OTHER PART GAINING STRENGTH NEAR THE FOUR
CORNERS. THIS INITIALLY THINS OUT THE PLUME OF SUBTROPICAL MOISTURE
STREAMING OVER COLORADO. HOWEVER BY LATE ON SATURDAY THE MONSOONAL
FLOW OF MOIST AIR RESUMES...RESULTING IN ANOTHER ROUND OF SCATTERED
SHOWERS/T-STORMS SATURDAY AFTERNOON AND EVENING...SOME POSSIBLY
PRODUCING LOCALLY HEAVY RAINFALL. HOWEVER STORM DEVELOPMENT ON
SUNDAY APPEARS TO CONCENTRATE MORE OVER THE HIGH COUNTRY WITH LOW
LEVELS APPEARING DRIER ON THE PLAINS. TEMPERATURES BOTH DAYS REMAIN
NEAR TO SLIGHTLY ABOVE AVERAGE.
BY MONDAY...THE CORE OF THE SUBTROPICAL MOISTURE PLUME IS PROGGED TO
SHIFT EVEN FARTHER WEST AWAY FROM THE FRONT RANGE WITH THE FLOW
ALOFT BECOMING MORE EAST-SOUTHEASTERLY IN DIRECTION WITH THE UPPER
HIGH OVER THE FOUR CORNERS FALLING APART. THEREFORE CHANCES FOR
PRECIP ON MONDAY APPEAR MUCH LOWER ESPLY EAST OF THE MTNS. MODELS
ALSO INDICATE SLIGHTLY COOLER TEMPERATURES ON MONDAY. NOT QUITE SURE
WHY...POSSIBLY DUE TO GREAT CLOUD COVER. BY TUESDAY...THE HIGHEST
SPECIFIC HUMIDITIES REMAIN WEST OF THE CONTINENTAL DIVIDE AS
STEERING WINDS ALOFT TURN MORE SOUTHERLY DURING THE DAY. WILL WILL
HELP TO INCREASE TEMPERATURES PARTICULARLY ON THE PLAINS.
&&
.AVIATION...A WEAK DENVER CYCLONE HAS DEVELOPED OVER DIA EARLY
THIS MORNING. AS MENTIONED ABV MOST OF THE SHORT RANGE MODELS WIPE
IT OUT BY MIDDAY WITH RATHER STG SSE LOW LVL DEVELOPING. THE WRF
IS THE ONLY MODEL WHICH KEEPS THE CYCLONE INTACT THRU THE AFTN
WHICH LEADS TO VARYING WIND DIRECTIONS DEPENDING ON WHERE IT
RESIDES. FOR NOW WILL KEEP WINDS SSE THRU THE AFTN. LATEST DATA
SUGGEST TSTMS COULD DVLP AS EARLY AS 19Z AND THEN MOVE EAST OF THE
AIRPORT BY 23Z. ITS ENTIRELY POSSIBLE IF THE DENVER CYCLONE GETS
WIPED OUT THAT TSTMS MAY NOT AFFECT THE AIRPORT AT ALL AS THEY
FOCUS TO THE EAST AND SOUTH HOWEVER WILL KEEP A PROB GROUP IN THE
TAF. IF A STRONGER STORM WERE TO AFFECT THE AIRPORT THEN MAY SEE
BRIEF MVFR CONDITIONS IN THE 19Z-23Z TIMEFRAME.
BY THIS EVENING IT LOOKS LIKE THE TSTM THREAT WILL REMAIN TO THE
EAST OF THE AIRPORT. RIGHT NOW THE MODELS SHOW EITHER A SLY OR
SELY COMPONENT FOR WINDS WHICH BECOME MORE SSW AFTER 06Z.
&&
.HYDROLOGY...SCATTERED THUNDERSTORMS WILL DEVELOP BY EARLY AFTN.
POTENTIAL RAINFALL AMOUNTS IN THE BURN AREAS WILL BE IN THE 0.25
TO 0.50 RANGE.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RPK
LONG TERM....BAKER
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS PUEBLO CO
126 AM MDT WED JUL 10 2013
.UPDATE...
ISSUED AT 125 AM MDT WED JUL 10 2013
ADDED ISOLATED THUNDERSTORMS TO SOME EASTERN PLAINS GRIDS/ZONES
AND ALSO ADJUSTED ADDITIONAL METEOROLOGICAL ELEMENTS TO REFLECT
RECENT MET CONDITIONS.
&&
.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 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1059 PM MDT TUE JUL 9 2013
VFR CONDITIONS ARE GENERALLY EXPECTED AT KCOS...KPUB AND KALS FOR THE NEXT
24 HOURS. SOME ISOLD TSTMS ARE STILL POSSIBLE TONIGHT IN THE VCNTY
OF KCOS. ON WEDNESDAY...MAINLY BETWEEN 18Z AND 02Z THE TERMINAL SITES
WILL HAVE THE POTENTIAL FOR SHOWERS AND TSTMS IN THE VCNTY. THERE
IS A SMALL CHANCE THAT MODERATE TO HEAVY RAIN COULD CAUSE MVFR
CONDITIONS BRIEFLY.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1112 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 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1059 PM MDT TUE JUL 9 2013
VFR CONDITIONS ARE GENERALLY EXPECTED AT KCOS...KPUB AND KALS FOR THE NEXT
24 HOURS. SOME ISOLD TSTMS ARE STILL POSSIBLE TONIGHT IN THE VCNTY
OF KCOS. ON WEDNESDAY...MAINLY BETWEEN 18Z AND 02Z THE TERMINAL SITES
WILL HAVE THE POTENTIAL FOR SHOWERS AND TSTMS IN THE VCNTY. THERE
IS A SMALL CHANCE THAT MODERATE TO HEAVY RAIN COULD CAUSE MVFR
CONDITIONS BRIEFLY.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...ROSE
LONG TERM...LW
AVIATION...28
AREA FORECAST DISCUSSION
NWS MIAMI FL
947 PM EDT THU JUL 11 2013
.UPDATE...
SLIGHT CHANGES WERE DONE TO THE FIRST PERIOD OF THE FORECAST
PACKAGE TO MATCH WITH THIS EVENING`S WEATHER PATTERN. LATEST MODEL
GUIDANCE CONTINUES TO SHOW THE REMNANTS OF CHANTAL REMAINING
OFFSHORE ACROSS THE ATLANTIC OVERNIGHT...WHICH COINCIDES WITH
PREVIOUS MODELS RUNS. 00Z SOUNDING DEPICTING A LIGHT EASTERLY FLOW
AT LOW LEVELS...WHICH COULD HELP BRINGING A FEW SHOWERS THROUGH
THE NIGHT ACROSS THE PENINSULA. CURRENT FORECAST SHOWING EXACTLY
THIS TREND...THEREFORE NO CHANGES WERE NEEDED.
&&
.PREV DISCUSSION... /ISSUED 801 PM EDT THU JUL 11 2013/
AVIATION...
THE WEATHER SHOULD REMAIN DRY TONIGHT OVER ALL OF THE TAF SITES
ACROSS SOUTH FLORIDA ALONG WITH LIGHT AND VARIABLE WINDS. THE
WINDS WILL THEN BECOME SOUTHWEST ON FRIDAY AT 5 TO 10 MPH IN THE
MORNING WITH A SLIGHT CHANCE OF SHOWERS. THE EAST COAST SEA BREEZE
SHOULD DEVELOP LATE IN THE DAY AND PUSH INLAND TO ABOUT THE KFXE
AND KTMB TAF SITES BETWEEN 19Z AND 20Z. SO WILL MAKE THE WINDS BE
BETWEEN 170 AND 190 ALONG THE EAST COAST TAF SITES BETWEEN 19Z AND
20Z ON FRIDAY. THERE WILL ALSO BE THE CHANCE OF THUNDERSTORMS
ALONG THE EAST COAST TAF SITES AFTER 19Z. SO HAVE ADDED VCTS TO
THE EAST COAST TAF SITES AFTER 19Z ON FRIDAY. THE CEILING AND VIS
SHOULD REMAIN IN THE VFR CONDITIONS AT ALL OF THE TAF SITES
TONIGHT INTO FRIDAY.
AVIATION..54/BNB
PREV DISCUSSION... /ISSUED 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...17/ERA
AVIATION/RADAR...54/BNB
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
937 PM EDT Thu Jul 11 2013
.NEAR TERM [through Rest of Tonight]...
The large scale longwave pattern remains amplified. This is
highlighted by an expansive ridge over Wrn states to Canadian
Prairies with center over Srn plains, a upper trough from Nrn Que
thru Great Lakes to low in OH Valley was drifting ewd with an H5
trough from mid- Appalachian mountains south thru GA and the FL
Panhandle into Nrn Gulf, and a ridge over Wrn Atlc. Looking south,
TUTT located between FL Keys and Cuba. At surface, high over Wrn
Great Lakes with ridge from Plains to Great Lakes and a front from
St Lawrence valley SWWD thru mid-Atlc thru Apalachee Bay to Cntrl
Gulf Coast. High well off Carolina Coast with axis SWWD to FL to
high over N/Cntrl Gulf of Mex. Finally remnants of Chantal was
located over Bahamas and Cuba. All this places local area in warm
sector below and under influence of deep layer tropical moisture
advecting newd. Area model soundings show that area PWATS will
remain well over 2 inches.
During the late aftn into early eve, the combination of the troughs,
mesoscale boundaries emanating from upstream MCS and juicy airmass
generating scattered to numerous showers and thunderstorms across
the area. Under a Gulf seabreeze regime, under weak steering flow,
this activity moved generally slowly Newd impacting mainly SE
half of forecast area. These slow moving storms generated locally
heavy rains across the Tallahassee metro area during the mid aftn
period resulting in localized or nuisance flooding. By 7 pm EDT,
precip continued to wane with increasing loss of heat and was
occurring primarily east of the Apalachicola and Chattahoochee
Rivers. For the rest of this late eve into the overnight hours,
scattered shwrs and isold storms ahead of the cold front will
continue to track south although they will remain focused across
the ne tier GA counties. Also, HI RES models like HRRR and WRF
show convection developing late over the waters, especially
Panhandle waters. So expect 20-30% POP gradient. Will update 1st
period grids accordingly. Lows in the low 70s inland to mid 70s
at the coast.
&&
.SHORT TERM [Friday through Saturday Night]...
An upper low will cut off over the Ohio River near the OH/WV border
Friday morning and then begin retrograding to a position near the
Mid Mississippi Valley by Saturday night. At the surface, a front
over the Tennessee Valley will sag south to near the Gulf Coast on
Friday and remain in place through the period. This front will be
the focus for numerous showers and thunderstorms. On Friday, PoPs
will range from likely northwest to categorical southeast with only
about a 10% drop off for Saturday. With PW holding up around 2
inches, we expect the primary weather impact to be locally heavy
rain. Since flash flood guidance remains low, localized flooding
will also be a concern. Temps will be held a few degrees below
normal due to all of the clouds and convective coverage.
&&
.LONG TERM [Sunday through Thursday]...
The long wave pattern will be in retrogression through much of this
period. An upper low will track from the Midwest to the Central or
Southern Plains (depending on the model you pick) as a ridge pushes
in from the Atlantic. Beneath this ridge, a TUTT will track west
across FL Monday night through Wednesday. At the surface, a front
will lift north across the region on Sunday with the subtropical
"Bermuda" ridge axis mainly north of the area after that. That will
put the area in an easterly flow regime at lower levels. Typical mid
range PoPs are expected through the period with development largely
driven by land and sea breeze circulations. Max temps will be a
couple of degrees below normal with mins close to normal.
&&
.AVIATION...[through 00 UTC Saturday]
Generally, VFR conditions will prevail past midnight. Overnight,
low ceilings will impact most terminals with patchy MVFR fog
possible as well, especially near sites receiving rain today. VFR
should return a few hours after sunrise tomorrow then expect
numerous showers with a chance of showers and thunderstorms thru
00z. Again, within storms expect low end IFR conditions with gusty
winds into this late eve.
&&
.MARINE...
Light winds and low seas will prevail within a weak pressure pattern
through the weekend. An easterly flow regime will set up by early
next week with a slight increase in winds speeds by Monday night and
Tuesday.
&&
.FIRE WEATHER...
Red Flag conditions are not anticipated for the foreseeable future.
&&
.HYDROLOGY...
Heavy rainfall last week caused flooding at several sites on area
rivers and excessive flash flooding in parts of the FL Panhandle.
This, combined with upcoming rainfall has caused concern for
continued area flooding, and potentially additional flash flooding
later this week in already hard hit areas. The WPC outlook shows
1-2" of rain over today and tomorrow, although locally higher
amounts of 2-4" are possible and are shown in the mean QPF values
from our hi-res guidance. While 1-2" is pretty low for our area,
with flooding still occurring or having only just receded, certain
areas, especially the rivers listed below and the FL Panhandle, are
at an increased risk for flooding potential this week.
The following rivers are at flood stage:
* Apalachicola River at Blountstown - In minor flood stage and
rising to a peak of 16.8 ft Saturday, after which the river is
expected to recede through early next week.
* Choctawhatchee River at Caryville - In minor flood stage and
gradually falling through early next week.
* Choctawhatchee River at Bruce - In major flood stage and
gradually decreasing through next week.
* Aucilla River at Lamont - In minor flood stage with a broad crest
through early next week.
* St. Marks River at Newport - In minor flood stage with a
gradual rise heading into a broad crest over the weekend.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 72 87 72 89 72 / 40 80 40 60 30
Panama City 75 88 74 90 74 / 40 70 30 40 30
Dothan 73 91 72 91 72 / 40 50 20 50 30
Albany 73 88 72 89 72 / 50 60 30 60 30
Valdosta 71 87 70 86 70 / 50 80 50 60 30
Cross City 72 86 71 88 71 / 50 80 50 60 30
Apalachicola 73 86 72 88 74 / 40 80 40 50 30
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
Hydrology...Moore
Short Term/Long Term/Marine...Wool
Rest of Discussion...Harrigan
AREA FORECAST DISCUSSION
NWS MIAMI FL
801 PM EDT THU JUL 11 2013
.AVIATION...
THE WEATHER SHOULD REMAIN DRY TONIGHT OVER ALL OF THE TAF SITES
ACROSS SOUTH FLORIDA ALONG WITH LIGHT AND VARIABLE WINDS. THE
WINDS WILL THEN BECOME SOUTHWEST ON FRIDAY AT 5 TO 10 MPH IN THE
MORNING WITH A SLIGHT CHANCE OF SHOWERS. THE EAST COAST SEA BREEZE
SHOULD DEVELOP LATE IN THE DAY AND PUSH INLAND TO ABOUT THE KFXE
AND KTMB TAF SITES BETWEEN 19Z AND 20Z. SO WILL MAKE THE WINDS BE
BETWEEN 170 AND 190 ALONG THE EAST COAST TAF SITES BETWEEN 19Z AND
20Z ON FRIDAY. THERE WILL ALSO BE THE CHANCE OF THUNDERSTORMS
ALONG THE EAST COAST TAF SITES AFTER 19Z. SO HAVE ADDED VCTS TO
THE EAST COAST TAF SITES AFTER 19Z ON FRIDAY. THE CEILING AND VIS
SHOULD REMAIN IN THE VFR CONDITIONS AT ALL OF THE TAF SITES
TONIGHT INTO FRIDAY.
&&
.AVIATION..54/BNB
.PREV DISCUSSION... /ISSUED 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...84/AK
AVIATION/RADAR...10/CD
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
345 PM EDT WED JUL 10 2013
.SYNOPSIS...
19Z WATER VAPOR AND H4 RAP ANALYSIS CONTINUES TO SHOW AN UPPER LEVEL
PATTERN OVER THE CONUS DOMINATED BY A PROGRESSIVE NORTHERN STREAM
FLOW ALONG THE U.S/CANADIAN BORDER OVER-TOP AN AN ELONGATED AND
BROAD WEST TO EAST ORIENTED RIDGE. OTHER FEATURE OF NOTE REMAINS A
WEAKENING TUTT FEATURE/UPPER LOW MIGRATING WESTWARD OVER SOUTH
FL/FLORIDA STRAITS. THIS FEATURE LOOKS TO HAVE LIMITED IMPACT ON OUR
WEATHER OTHER THAN SOME INCREASE IN COLUMN MOISTURE...AND MAINLY FOR
THE SOUTHERN HALF OF OUR AREA. AT THIS POINT...THE THERMAL ANOMALY
NORMALLY ASSOCIATED WITH TUTT CELLS THAT CAN ENHANCE INSTABILITY
OVER LAND HAS ESSENTIALLY COLLAPSED...AND ANY INFLUENCE IT CAN STILL
HAVE WILL BE FELT MAINLY OVER FAR SOUTHERN PORTIONS OF THE
PENINSULA.
AT THE SURFACE...LOCAL REGION IS EXPERIENCING A WEAK GRADIENT JUST
TO THE SOUTH OF A BROAD SURFACE RIDGE AXIS EXTENDING FROM THE
NORTH-CENTRAL GULF OF MEXICO TO NORTHERN FLORIDA AND THE GA/SC
COAST.
&&
.SHORT TERM (THIS EVENING THROUGH FRIDAY)...
THROUGH THIS EVENING...
THE WEAK GRADIENT IS ALLOWING FOR THE WEST-COAST SEA-BREEZE TO
MIGRATE A BIT FURTHER INLAND THIS AFTERNOON. HOWEVER...THE RESIDUAL
LIGHT EASTERLY FLOW IS ONCE AGAIN RESULTING IN A WEST COAST DOMINANT
CONVECTIVE PATTERN. HI-RESOLUTION CONVECTIVE ALLOWING MODEL SUITE
SEEMS ON TRACK INITIATING FIRST CONVECTION DOWN TOWARD FT. MYERS AND
THEN "RIPPLING" NORTHWARD UP THE COAST THROUGH THE LATE AFTERNOON
AND EARLY EVENING. POP FORECAST WILL CONTINUE TO FOLLOW THIS TREND
WITH HIGHEST RAIN CHANCES THROUGH MID AFTERNOON OVER THE SOUTHERN
ZONES...AND THEN INCREASING LATE AFTERNOON/EARLY EVENING FURTHER
NORTH TOWARD TAMPA BAY AND THE NATURE COAST.
TONIGHT...
EVENING STORMS DISSIPATE BY 02-03Z OR TRANSLATE OFFSHORE WITH TIME.
WEAK LEFTOVER VORTICITY LOBE FROM THE DECAYING TUTT IS FORECAST TO
RESIDE ALONG THE FLORIDA WEST COAST LATE TONIGHT INTO THURSDAY
MORNING. THIS WEAK CYCLONIC FLOW...AND ANY ASSOCIATED WEAK SURFACE
REFECTION/TROUGH FEATURE WOULD LIKELY ENHANCE THE NOCTURNAL STORM
POTENTIAL OVER THE COASTAL WATERS AFTER MIDNIGHT. MID-LEVEL FLOW IS
ALSO PROGGED BY LATEST NUMERICAL GUIDANCE TO COME AROUND TO A MORE
SOUTHERLY DIRECTION EARLY THURSDAY MORNING. THIS STEERING FLOW (IF
DEVELOPING QUICKLY ENOUGH) SHOULD RESULT IN SOME OF THIS NOCTURNAL
MARINE CONVECTION MIGRATING BACK TOWARD THE IMMEDIATE COAST AROUND
DAWN AND INTO AT LEAST THE FIRST FEW DAYLIGHT HOURS. ONCE AGAIN
CONVECTION ALLOWING GUIDANCE AND PARAMETRIZED GUIDANCE ALIKE ARE ALL
SHOWING THIS POTENTIAL FOR COASTAL SHOWERS/STORM TOMORROW MORNING.
THURSDAY...
SUBTROPICAL RIDGE AXIS WILL EXTEND ACROSS THE CENTRAL FL
PENINSULA...OR EVEN SOUTH-CENTRAL PENINSULA. EXPECTING TO CONTINUE
SEEING A SCATTERING OF SHOWERS NEAR THE COAST EARLY IN THE
MORNING...WITH THE ACTIVITY BECOME MORE ROBUST BY MIDDAY AS THE
SEA-BREEZE BECOMES ESTABLISHED. PLENTY OF DEEP LAYER MOISTURE WILL
BE IN PLACE MAKING FOR A FAVORABLE CONVECTIVE ENVIRONMENT. LIGHT
FLOW PATTERN NEAR THE RIDGE AXIS TO THE SOUTH OF I-4 WILL KEEP THE
SEA-BREEZE FROM MOVING INLAND ALL THAT FAST AND SHOULD SEE A FAIRLY
UNIFORM DISTRIBUTION OF CONVECTIVE COVERAGE DURING THE AFTERNOON
ACROSS THE SOUTHERN HALF OF THE PENINSULA. FURTHER NORTH ALONG THE
NATURE COAST...SYNOPTIC FLOW SHOULD AID THE INLAND PENETRATION OF
THIS BOUNDARY AND DECREASE RAIN CHANCES NEAR THE COAST AS WE HEAD
THROUGH THE AFTERNOON. THE TAMPA BAY AREA WILL BE THE TRANSITION
ZONES...BUT WOULD NOT BE SURPRISED TO SEE THE CONVECTION MOVE INLAND
AWAY FROM THE PINELLAS COAST DURING THE AFTERNOON AS WELL.
THURSDAY NIGHT SEES THE INLAND STORMS SLOWLY DISSIPATE AFTER SUNSET
WITH A GENERALLY DRY SECOND HALF OF THE NIGHT. A SIGNIFICANT
AMPLIFICATION TO THE UPPER LEVEL PATTERN WILL BE OCCURRING OVER THE
EASTERN CONUS THURSDAY AND THURSDAY NIGHT FOR THE MIDDLE OF JULY AND
THIS AMPLIFICATION WILL SEND A SURFACE FRONT TOWARD THE I-10
CORRIDOR. ALL GUIDANCE SHOWS THIS FRONT STALLING NORTH OF OUR
AREA...HOWEVER IT MAY BE JUST CLOSE ENOUGH TO ENHANCE THE SHOWER
ACTIVITY UP TOWARD LEVY/CITRUS COUNTIES BY LATE THURSDAY NIGHT.
FRIDAY IS THE DAY THAT THE CURRENT FORECAST HAS TROPICAL STORM
CHANTAL MOVING NEAR THE SOUTHEAST FL COAST AS A DEPRESSION. THERE IS
SOME CHANCE THAT CHANTAL WILL NOT EVEN SURVIVE AS A DEPRESSION THIS
LONG AND BE NO MORE THAN AN OPEN WAVE OR MID-LEVEL IMPULSE AS IT
MOVES NORTHWARD FROM THE CARIBBEAN. WE WILL BE WATCHING CLOSELY IN
CASE CHANTAL HOLDS TOGETHER LONGER...HOWEVER AT THIS TIME...THE
IMPACTS LOOK TO BE LITTLE MORE THAN SOME INCREASED MOISTURE AND
VORTICITY TO INDUCE AN ACTIVE AFTERNOON/EVENING OF STORMS. WILL HAVE
THE BEST RAIN CHANCES ALONG AND INLAND FROM THE I-75 CORRIDOR BY THE
TIME WE GET TO MID AFTERNOON AS THE LIGHT GRADIENT ALLOWS THE
SEA-BREEZE TO SLOWLY PROGRESS INLAND FROM THE BEACHES.
&&
.LONG TERM (SATURDAY THROUGH WEDNESDAY)...
THE START OF THE LONG TERM IS HIGHLY LINKED TO THE PROGRESS OF
TROPICAL STORM CHANTAL. WITH THE STORM/S CURRENT DISORGANIZED
STATUS...GUIDANCE IS WIDELY RANGING. RECENT MODEL TRENDS HAVE BEEN
TO BRING THE SYSTEM FURTHER WEST THAN EARLIER RUNS. IF THIS
SYSTEM IS ABLE TO SURVIVE...GUIDANCE SUGGESTS IT MAY ENTER A MORE
FAVORABLE ENVIRONMENT IN THE NORTHERN CARIBBEAN AND FLORIDA
STRAITS IF IT NEARS FLORIDA. THIS SYSTEM IS A BIT OF A FORECAST
MYSTERY AS ITS SURVIVAL IS NOT LOOKING LIKELY. THE 00Z CMC IS THE
MOST OPTIMISTIC MODEL FOR THE STORM NEARING OUR AREA AND
STRENGTHENING IN THE PROCESS...THIS APPEARS UNLIKELY. ON THE OTHER
END OF THE SPECTRUM...THE 12Z ECMWF DOES NOT REALLY HAVE CHANTAL
AS AN ORGANIZED SYSTEM EVEN AS IT GOES EAST OF FLORIDA. DECIDED TO
USE A MIDDLE-OF-THE-ROAD FORECAST PHILOSOPHY WITH THE EXTENDED
USING THE GFS AND GRIDDED MOS AS THE FOUNDATION.
PAST THE INITIAL CHALLENGE FROM THE TROPICS...A HIGH BUILDS IN OVER
THE EASTERN UNITED STATES. THIS PATTERN WILL ALLOW A RETURN TO
EASTERLY FLOW AND THE SUMMER THUNDERSTORM PATTERN ALL TOO FAMILIAR
TO WEST CENTRAL AND SOUTHWEST FLORIDA THIS SUMMER.
&&
.AVIATION...
BKN VFR CIGS WITH TSRA AT OR NEAR THE TERMINALS RESULTING IN LCL
MVFR VSBY/CIGS THROUGH SUNSET. WINDS ONSHORE OR BECOMING ONSHORE
ALONG THE COAST THIS AFTERNOON...VARIABLE OVERNIGHT...SE TO S THU
MORNING.
&&
.MARINE...
A WEAK PRESSURE GRADIENT WILL REMAIN IN PLACE ACROSS THE EASTERN
GULF OF MEXICO THROUGH THURSDAY NIGHT WITH A RIDGE AXIS IN THE
VICINITY. CONTINUING TO WATCH TROPICAL STORM CHANTAL IN THE CENTRAL
CARIBBEAN...HOWEVER IT NOW APPEARS THAT THIS SYSTEM WILL HAVE LITTLE
IMPACT ON THE WIND OR WAVE FORECASTS FOR THE EASTERN GULF OF MEXICO
THROUGH THE END OF THE WEEK.
&&
.FIRE WEATHER...
A TYPICAL SUMMER TYPE PATTERN WILL EXIST THE NEXT SEVERAL DAYS
DOMINATED BY MAINLY AFTERNOON AND EVENING SHOWERS AND STORMS. NO
SIGNIFICANT FIRE WEATHER CONCERNS ARE EXPECTED AS RELATIVE HUMIDITY
VALUES REMAIN WELL ABOVE CRITICAL LEVELS. NO SIGNIFICANT IMPACTS
(IF ANY) ARE ANTICIPATED DURING THE FORECAST PERIOD FROM WHAT IS
NOW TROPICAL STORM CHANTAL IN THE CENTRAL CARIBBEAN.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 77 89 77 89 / 50 40 20 40
FMY 74 91 74 91 / 30 50 20 60
GIF 73 92 73 92 / 20 50 30 60
SRQ 76 89 76 89 / 50 40 20 30
BKV 72 91 71 91 / 50 50 20 50
SPG 78 89 77 89 / 50 40 20 30
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/MARINE/FIRE WX...MROCZKA
LONG TERM...GARCIA
AVIATION...RUDE
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
1130 AM EDT WED JUL 10 2013
.UPDATE...
15Z WATER VAPOR AND H4 RAP ANALYSIS CONTINUES TO SHOW AN UPPER LEVEL
PATTERN OVER THE CONUS DOMINATED BY A PROGRESSIVE NORTHERN STREAM
FLOW ALONG THE U.S/CANADIAN BORDER OVER-TOP AN AN ELONGATED AND
BROAD WEST TO EAST ORIENTED RIDGE. OTHER FEATURE OF NOTE REMAINS A
WEAKENING TUTT FEATURE/UPPER LOW MIGRATING WESTWARD OVER SOUTH
FL/FLORIDA STRAITS. THIS FEATURE LOOKS TO HAVE LIMITED IMPACT ON OUR
WEATHER OTHER THAN SOME INCREASE IN COLUMN MOISTURE...AND MAINLY FOR
THE SOUTHERN HALF OF OUR AREA. AT THIS POINT...THE THERMAL ANOMALY
NORMALLY ASSOCIATED WITH TUTT CELLS THAT CAN ENHANCE INSTABILITY
OVER LAND HAS ESSENTIALLY COLLAPSED...AND ANY INFLUENCE IT CAN STILL
HAVE WILL BE FELT MAINLY OVER FAR SOUTHERN PORTIONS OF THE
PENINSULA.
AT THE SURFACE...LOCAL REGION IS EXPERIENCING A WEAK GRADIENT JUST
TO THE SOUTH OF A BROAD SURFACE RIDGE AXIS EXTENDING FROM THE
NORTH-CENTRAL GULF OF MEXICO TO NORTHERN FLORIDA AND THE GA/SC
COAST. THIS WEAK GRADIENT WILL ALLOW FOR THE WEST-COAST SEA-BREEZE
TO POTENTIALLY MIGRATE A BIT FURTHER INLAND THROUGH THE EARLY/MID
AFTERNOON. HOWEVER...THE RESIDUAL LIGHT EASTERLY FLOW WILL STILL
EVENTUALLY RESULT IN A WEST COAST DOMINANT CONVECTIVE PATTERN.
HI-RESOLUTION CONVECTIVE ALLOWING MODEL SUITE ALL SHOW CONVECTION
INITIATING FIRST DOWN TOWARD FT. MYERS AND THEN "RIPPLING" NORTHWARD
UP THE COAST. POP FORECAST WILL FOLLOW THIS TREND WITH HIGHEST RAIN
CHANCES THROUGH MID AFTERNOON OVER THE FAR SOUTHERN ZONES...AND THEN
INCREASING LATE AFTERNOON/EVENING FURTHER NORTH TOWARD TAMPA BAY AND
THE NATURE COAST.
WET MICROBURST POTENTIAL HAS DECREASED FOR MAJORITY OF THE AREA
WITH HIGHER VALUES OF THETA-E NOW FORECAST/OBSERVED AROUND 10-15KFT.
12Z NAM STILL SHOWED A DECENT PROFILE FOR WET-MICROBURST OVER THE
NORTHERN NATURE COAST ZONES (CITRUS/LEVY) LATER THIS AFTERNOON AND
WILL NEED TO KEEP A CLOSE EYE ON ANY STRONGER STORMS THAT FORM IN
THIS VICINITY. ELSEWHERE APPEARS HEAVIER RAINFALL AND FREQUENT
LIGHTNING WILL BE THE MAIN THREATS. BASED ON THE 12Z KTBW
SOUNDING...STORM MOTION TODAY ONCE FULLY MATURE WOULD BE TOWARD THE
WEST OR WEST-SW.
TONIGHT...
EVENING STORMS DISSIPATE BY 02-03Z OR TRANSLATE OFFSHORE WITH TIME.
WEAK LEFTOVER VORTICITY LOBE FROM THE DECAYING TUTT IS FORECAST TO
RESIDE ALONG THE FLORIDA WEST COAST LATE TONIGHT INTO THURSDAY
MORNING. THIS WEAK CYCLONIC FLOW...AND ANY ASSOCIATED WEAK SURFACE
REFECTION/TROUGH FEATURE WOULD LIKELY ENHANCE THE NOCTURNAL STORM
POTENTIAL OVER THE COASTAL WATERS. MID-LEVEL FLOW IS ALSO PROGGED BY
LATEST NUMERICAL GUIDANCE TO COME AROUND TO A MORE SOUTHERLY
DIRECTION EARLY THURSDAY MORNING. THIS STEERING FLOW (IF DEVELOPING
QUICKLY ENOUGH) SHOULD RESULT IN SOME OF THIS NOCTURNAL MARINE
CONVECTION MIGRATING BACK TOWARD THE IMMEDIATE COAST AROUND DAWN AND
INTO AT LEAST THE FIRST FEW DAYLIGHT HOURS. ONCE AGAIN CONVECTION
ALLOWING GUIDANCE AND PARAMETRIZED GUIDANCE ALIKE ARE ALL SHOWING
THIS POTENTIAL FOR COASTAL SHOWERS/STORM TOMORROW MORNING. CURRENT
GRIDS SHOW CHANCE POPS ALONG THE IMMEDIATE COAST DURING THE MORNING
ON THURSDAY...AND SEE LITTLE REASON FOR SIGNIFICANT UPDATES TO THIS
INHERITED FORECAST.
&&
.AVIATION...
VFR CONDITIONS WITH VCNTY SHRA EARLY AFTERNOON AND VCNTY TSRA LATER.
LCL MVFR/IFR AS CONVECTION CONTINUES UNTIL JUST AFTER SUNSET. LIGHT
VARIABLE/EASTERLY WINDS SHIFT TO ONSHORE ALONG THE COAST IN THE
AFTERNOON.
&&
.MARINE...
ALL EYES ON THE TROPICS FOR THE MARINE FORECAST. CURRENTLY...CHANTAL
IS TRENDING WEAKER AND FURTHER WEST. WILL NEED TO MONITOR SITUATION
AS GUIDANCE IS SPREAD INTO THE LONG TERM. IN GENERAL...HIGH PRESSURE
WILL KEEP THE WATERS BELOW SCEC CRITERIA WITH ONLY A NEARING
LOW...REMNANTS OF CHANTAL...TO DISRUPT THAT PATTERN.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 90 75 91 76 / 50 30 40 20
FMY 89 74 92 75 / 60 30 40 20
GIF 91 73 93 74 / 40 20 50 30
SRQ 89 74 90 76 / 60 40 40 20
BKV 92 72 92 71 / 40 30 50 30
SPG 91 77 90 77 / 60 40 40 20
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE...MROCZKA
AVIATION...RUDE
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
1020 AM EDT WED JUL 10 2013
.DISCUSSION...
SFC/BNDRY LYR WINDS HAVE VEERED TO SE IN THE WAKE OF A HI AMPLITUDE
EASTERLY WAVE EXTENDING FROM HAVANA TO JACKSONVILLE. EARLY MORNING
SHRA/TSRA ACTIVITY OVER THE GULF STREAM HAS SPUTTERED...MOST PRECIP
HAS TRANSITIONED FROM CONVECTIVE TO STRATIFORM IN NATURE. EVEN SO...
LATEST RUC ANALYSIS SHOWS AN AREA OF STRONG COUPLET OF MID LVL OMEGA
LIFT/UPR LVL DIVERGENCE CO-LOCATED WITH AN AREA OF RESPECTABLE MID
LVL VORTICITY ON THE BACKSIDE OF THE WAVE.
MORNING SOUNDINGS SHOW DEEP MOISTURE WORKING ITS WAY BACK INTO THE
CENTRAL PENINSULA WITH KXMR/KTBW/KMFL PWATS BTWN 1.8"-2.0"...DRY AIR
LINGERS TO THE N WITH KJAX PWAT ARND 1.3"...BUT A 2.0" PWAT AT KTLH
SUGGESTS THIS DRY AIR SOON WILL BE OVERCOME BY HI MOISTURE POOLING
WITHIN A TROF OVER THE DEEP SOUTH.
MUCH OF THE PENINSULA IS UNDER AN H100-H85 DEFORMATION ZONE THAT
WILL INITIALLY IMPEDE DIURNAL CONVECTION. HOWEVER...SRLY FLOW WILL
STRENGTHEN AS THE ERLY WAVE PUSHES INTO THE ERN GOMEX AND IS
ABSORBED BY THE TROF OVER THE DEEP SOUTH...ALLOWING ADDITIONAL
MOISTURE AS WELL FAVORABLE DYNAMIC LIFT TO PUSH INTO THE PENINSULA.
SHOULD SEE THE EAST COAST SEA BREEZE FORM BY MIDDAY WITH ISOLD/SCT
CONVECTION DVLPG ALONG THE BOUNDARY...PUSHING TO THE VCNTY OF THE FL
TURNPIKE BY LATE AFTN WITH COVERAGE BCMG SCT OVER THE INTERIOR.
&&
.AVIATION...
S OF KTIX-KISM...THRU 11/00Z SCT MVFR SHRAS/ISOLD IFR TSRAS...BCMG
ISOLD MVFR SHRAS AFT 11/00Z AND CONTG THRU 10-12Z.
N OF KTIX-KISM...THRU 10/18Z VFR ALL SITES. BTWN 10/18Z-11/00Z...SCT
MVFR SHRAS/ISOLD IFR TSRAS. AFT 11/00Z PREVAILING VFR ALL SITES...
ISOLD MVFR SHRAS COASTAL SITES BTWN KMLB-KOMN.
&&
.MARINE...
SFC/BNDRY LYR WINDS HAVE VEERED TO SE IN THE WAKE OF A HI AMPLITUDE
EASTERLY WAVE EXTENDING FROM HAVANA TO JACKSONVILLE. LATEST DATA
BUOY/C-MAN OBS SHOW SFC WINDS AOB 10KTS WITH SEAS AOB 2FT NEARSHORE
AND 2-3FT OFFSHORE. SHOULD SEE WINDS INCREASE NEARSHORE BY MIDDAY AS
THE EAST COAST SEA BREEZE DVLPS AND PUSHES INLAND. AREAS OF RAIN S
OF SEBASTIAN INLET WITH ISOLD SHRAS/TSRAS OVER THE GULF STREAM.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
FORECAST....BRAGAW
IMPACT WX...CRISTALDI
AREA FORECAST DISCUSSION...UPDATED
NWS MIAMI FL
938 AM EDT WED JUL 10 2013
.UPDATE...
THE UPPER LEVEL LOW OVER THE FLORIDA STRAITS THIS MORNING WILL
CONTINUE TO MOVE SLOWLY WEST SOUTHWEST TOWARDS THE SOUTHEAST GULF
OF MEXICO...AS HIGH PRESSURE SLOWLY WEAKENS OVER THE WESTERN
ATLANTIC WATERS. THIS WILL ALLOW FOR A LIGHT SOUTH TO SOUTHEAST
STEERING FLOW OVER THE CWA ALONG WITH THE ATMOSPHERE BEING
UNSTABLE DUE TO THE COLD AIR ALOFT ASSOCIATED WITH THE UPPER LEVEL
LOW. SO WILL CONTINUE THE SCATTERED TO NUMEROUS POPS OVER SOUTH
FLORIDA FOR THIS AFTERNOON...AND ADD LOCALLY HEAVY RAINFALL
WORDING TO THE ZONES DUE TO THE SLOW STEERING FLOW. REST OF THE
FORECAST LOOKS GOOD AT THIS TIME AND NO OTHER CHANGES ARE PLANNED.
&&
.UPDATE...54/BNB
.PREV DISCUSSION... /ISSUED 729 AM EDT WED JUL 10 2013/
AVIATION...
THE COMBINATION OF A LINGERING LOW LEVEL TROUGH...DEEP TROPICAL
MOISTURE AND AN UPPER LEVEL LOW INFLUENCING THE REGION WILL LEAD TO
CHANCES OF SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS BY LATE
MORNING TO EARLY AFTERNOON. THE COVERAGE OF THUNDERSTORMS IS
EXPECTED TO BE GREATEST IN THE INTERIOR PORTIONS OF THE PENINSULA. WITH
SHOWERS/THUNDERSTORMS...BRIEF PERIODS OF IFR CONDITIONS ARE
POSSIBLE. A FEW STRONG THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON.
&&
PREV DISCUSSION... /ISSUED 350 AM EDT WED JUL 10 2013/
.WATCHING DISORGANIZED TROPICAL STORM CHANTAL...
DISCUSSION...SATELLITE AND RADAR IMAGERY SHOWS CONVECTION
EXTENDING FROM THE ATLANTIC WATERS OFF THE SE FLORIDA COAST
EXTENDING ACROSS THE BAHAMAS INTO EASTERN CUBA. THIS IS ASSOCIATED
WITH A MID-UPPER LEVEL LOW WHICH WILL TRACK WESTWARD TODAY. A
SURFACE TROUGH IS ALIGNED ACROSS SOUTH FL AT THIS TIME AND WILL
CONTINUE TO MOVE NW. THIS WILL PLACE SOUTH FL IN A MOIST SOUTHERLY
FLOW TODAY-THURSDAY BEHIND THIS TROUGH AXIS.
FOR THE NEAR TERM THROUGH EARLY THIS MORNING...EXPECT RAIN TO
CONTINUE ALONG MUCH OF THE PALM BEACH COAST EXTENDING INTO
NORTHEASTERN BROWARD COUNTY AS WELL. HAVE INCREASED POPS
SUBSTANTIALLY ACROSS THESE AREAS FOR EARLY THIS MORNING BASED ON
CURRENT ACTIVITY AND TRENDS.
FOR TODAY...GFS MOS POPS HAVE DECREASED AND THE LATEST HRRR RUN
SHOWS SOME ACTIVITY ALONG THE ATLANTIC COAST BEFORE FOCUSING
MOSTLY INLAND IN THE AFTERNOON. HRRR DOES NOT HAVE A GOOD HANDLE
ON CURRENT ACTIVITY BUT IT`S TREND SEEMS REASONABLE FOR TODAY,
SO WILL FOLLOW THIS TREND, BUT WITH SLIGHTLY HIGHER POPS THAN GFS
MOS...MORE IN LINE WITH NAM MOS.
LOCALIZED HEAVY RAINFALL IS POSSIBLE TODAY-THURSDAY ALONG WITH
THE POTENTIAL OF A FEW THUNDERSTORMS CONTAINING GUSTY WINDS.
HOWEVER, INCREASING CLOUDINESS WILL ACT TO LIMIT INSTABILITY, SO
MOST OF THE TSTORMS WILL BE ORDINARY.
THE FORECAST FOR FRIDAY AND THIS WEEKEND WILL BE HIGHLY DEPENDENT ON
THE TRACK AND INTENSITY OF TROPICAL STORM CHANTAL, OR WHAT`S LEFT OF
IT. LET`S JUST SAY CHANTAL HAS SEEN BETTER DAYS. AS NHC
STATED...REPORTS FROM AN AIR FORCE HURRICANE HUNTER AIRCRAFT AND
SATELLITE IMAGES INDICATE THAT CHANTAL IS LOSING ORGANIZATION. GIVEN
THIS TREND AND LAND INTERACTION UPCOMING, CHANTAL WILL HAVE TO HANG
ON TOUGH TO BE A SYSTEM NORTH OF THE GREATER ANTILLES. GIVEN THE
HIGH UNCERTAINTY INVOLVED, THE FORECAST FOR THE LONGER TERM PERIOD
WILL CONTINUE TO REFLECT CLIMO CONDITIONS. IN OTHER WORDS, A
CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY WITH LITTLE CHANGE IN
TEMPS/HUMIDITY LEVELS. SUMMERTIME IN FLORIDA.
MARINE...SE WINDS LESS THAN 15 KT WITH LOW SEAS WILL PREVAIL
THROUGH THU. THE FORECAST FOR FRIDAY AND THIS WEEKEND IS ALL
DEPENDENT ON TS CHANTAL. WINDS/SEAS COULD PICK UP QUITE A BIT OR
REMAIN RATHER LOW...IT JUST ALL DEPENDS ON WHAT TRANSPIRES WITH
CHANTAL. IT IS LOOKING POORLY ORGANIZED AT THE MOMENT.
FIRE WEATHER...NO CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 76 88 78 / 50 30 50 30
FORT LAUDERDALE 88 79 89 79 / 50 30 50 40
MIAMI 89 77 89 78 / 50 30 50 40
NAPLES 89 73 90 75 / 50 30 50 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...57/DG
AVIATION/RADAR...57/DG
AREA FORECAST DISCUSSION
NWS MIAMI FL
729 AM EDT WED JUL 10 2013
.AVIATION...
THE COMBINATION OF A LINGERING LOW LEVEL TROUGH...DEEP TROPICAL
MOISTURE AND AN UPPER LEVEL LOW INFLUENCING THE REGION WILL LEAD TO
CHANCES OF SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS BY LATE
MORNING TO EARLY AFTERNOON. THE COVERAGE OF THUNDERSTORMS IS
EXPECTED TO BE GREATEST IN THE INTERIOR PORTIONS OF THE PENINSULA. WITH
SHOWERS/THUNDERSTORMS...BRIEF PERIODS OF IFR CONDITIONS ARE
POSSIBLE. A FEW STRONG THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 350 AM EDT WED JUL 10 2013/
..WATCHING DISORGANIZED TROPICAL STORM CHANTAL...
DISCUSSION...SATELLITE AND RADAR IMAGERY SHOWS CONVECTION
EXTENDING FROM THE ATLANTIC WATERS OFF THE SE FLORIDA COAST
EXTENDING ACROSS THE BAHAMAS INTO EASTERN CUBA. THIS IS ASSOCIATED
WITH A MID-UPPER LEVEL LOW WHICH WILL TRACK WESTWARD TODAY. A
SURFACE TROUGH IS ALIGNED ACROSS SOUTH FL AT THIS TIME AND WILL
CONTINUE TO MOVE NW. THIS WILL PLACE SOUTH FL IN A MOIST SOUTHERLY
FLOW TODAY-THURSDAY BEHIND THIS TROUGH AXIS.
FOR THE NEAR TERM THROUGH EARLY THIS MORNING...EXPECT RAIN TO
CONTINUE ALONG MUCH OF THE PALM BEACH COAST EXTENDING INTO
NORTHEASTERN BROWARD COUNTY AS WELL. HAVE INCREASED POPS
SUBSTANTIALLY ACROSS THESE AREAS FOR EARLY THIS MORNING BASED ON
CURRENT ACTIVITY AND TRENDS.
FOR TODAY...GFS MOS POPS HAVE DECREASED AND THE LATEST HRRR RUN
SHOWS SOME ACTIVITY ALONG THE ATLANTIC COAST BEFORE FOCUSING
MOSTLY INLAND IN THE AFTERNOON. HRRR DOES NOT HAVE A GOOD HANDLE
ON CURRENT ACTIVITY BUT IT`S TREND SEEMS REASONABLE FOR TODAY,
SO WILL FOLLOW THIS TREND, BUT WITH SLIGHTLY HIGHER POPS THAN GFS
MOS...MORE IN LINE WITH NAM MOS.
LOCALIZED HEAVY RAINFALL IS POSSIBLE TODAY-THURSDAY ALONG WITH
THE POTENTIAL OF A FEW THUNDERSTORMS CONTAINING GUSTY WINDS.
HOWEVER, INCREASING CLOUDINESS WILL ACT TO LIMIT INSTABILITY, SO
MOST OF THE TSTORMS WILL BE ORDINARY.
THE FORECAST FOR FRIDAY AND THIS WEEKEND WILL BE HIGHLY DEPENDENT ON
THE TRACK AND INTENSITY OF TROPICAL STORM CHANTAL, OR WHAT`S LEFT OF
IT. LET`S JUST SAY CHANTAL HAS SEEN BETTER DAYS. AS NHC
STATED...REPORTS FROM AN AIR FORCE HURRICANE HUNTER AIRCRAFT AND
SATELLITE IMAGES INDICATE THAT CHANTAL IS LOSING ORGANIZATION. GIVEN
THIS TREND AND LAND INTERACTION UPCOMING, CHANTAL WILL HAVE TO HANG
ON TOUGH TO BE A SYSTEM NORTH OF THE GREATER ANTILLES. GIVEN THE
HIGH UNCERTAINTY INVOLVED, THE FORECAST FOR THE LONGER TERM PERIOD
WILL CONTINUE TO REFLECT CLIMO CONDITIONS. IN OTHER WORDS, A
CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY WITH LITTLE CHANGE IN
TEMPS/HUMIDITY LEVELS. SUMMERTIME IN FLORIDA.
MARINE...SE WINDS LESS THAN 15 KT WITH LOW SEAS WILL PREVAIL
THROUGH THU. THE FORECAST FOR FRIDAY AND THIS WEEKEND IS ALL
DEPENDENT ON TS CHANTAL. WINDS/SEAS COULD PICK UP QUITE A BIT OR
REMAIN RATHER LOW...IT JUST ALL DEPENDS ON WHAT TRANSPIRES WITH
CHANTAL. IT IS LOOKING POORLY ORGANIZED AT THE MOMENT.
FIRE WEATHER...NO CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 76 88 78 / 50 30 50 30
FORT LAUDERDALE 87 79 89 79 / 50 30 50 40
MIAMI 88 77 89 78 / 50 30 50 40
NAPLES 87 73 90 75 / 50 30 50 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...54/BNB
AVIATION/RADAR...23/SK
AREA FORECAST DISCUSSION
NWS MIAMI FL
350 AM EDT WED JUL 10 2013
...WATCHING DISORGANIZED TROPICAL STORM CHANTAL...
.DISCUSSION...SATELLITE AND RADAR IMAGERY SHOWS CONVECTION
EXTENDING FROM THE ATLANTIC WATERS OFF THE SE FLORIDA COAST
EXTENDING ACROSS THE BAHAMAS INTO EASTERN CUBA. THIS IS ASSOCIATED
WITH A MID-UPPER LEVEL LOW WHICH WILL TRACK WESTWARD TODAY. A
SURFACE TROUGH IS ALIGNED ACROSS SOUTH FL AT THIS TIME AND WILL
CONTINUE TO MOVE NW. THIS WILL PLACE SOUTH FL IN A MOIST SOUTHERLY
FLOW TODAY-THURSDAY BEHIND THIS TROUGH AXIS.
FOR THE NEAR TERM THROUGH EARLY THIS MORNING...EXPECT RAIN TO
CONTINUE ALONG MUCH OF THE PALM BEACH COAST EXTENDING INTO
NORTHEASTERN BROWARD COUNTY AS WELL. HAVE INCREASED POPS
SUBSTANTIALLY ACROSS THESE AREAS FOR EARLY THIS MORNING BASED ON
CURRENT ACTIVITY AND TRENDS.
FOR TODAY...GFS MOS POPS HAVE DECREASED AND THE LATEST HRRR RUN
SHOWS SOME ACTIVITY ALONG THE ATLANTIC COAST BEFORE FOCUSING
MOSTLY INLAND IN THE AFTERNOON. HRRR DOES NOT HAVE A GOOD HANDLE
ON CURRENT ACTIVITY BUT IT`S TREND SEEMS REASONABLE FOR TODAY,
SO WILL FOLLOW THIS TREND, BUT WITH SLIGHTLY HIGHER POPS THAN GFS
MOS...MORE IN LINE WITH NAM MOS.
LOCALIZED HEAVY RAINFALL IS POSSIBLE TODAY-THURSDAY ALONG WITH
THE POTENTIAL OF A FEW THUNDERSTORMS CONTAINING GUSTY WINDS.
HOWEVER, INCREASING CLOUDINESS WILL ACT TO LIMIT INSTABILITY, SO
MOST OF THE TSTORMS WILL BE ORDINARY.
THE FORECAST FOR FRIDAY AND THIS WEEKEND WILL BE HIGHLY DEPENDENT ON
THE TRACK AND INTENSITY OF TROPICAL STORM CHANTAL, OR WHAT`S LEFT OF
IT. LET`S JUST SAY CHANTAL HAS SEEN BETTER DAYS. AS NHC
STATED...REPORTS FROM AN AIR FORCE HURRICANE HUNTER AIRCRAFT AND
SATELLITE IMAGES INDICATE THAT CHANTAL IS LOSING ORGANIZATION. GIVEN
THIS TREND AND LAND INTERACTION UPCOMING, CHANTAL WILL HAVE TO HANG
ON TOUGH TO BE A SYSTEM NORTH OF THE GREATER ANTILLES. GIVEN THE
HIGH UNCERTAINTY INVOLVED, THE FORECAST FOR THE LONGER TERM PERIOD
WILL CONTINUE TO REFLECT CLIMO CONDITIONS. IN OTHER WORDS, A
CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY WITH LITTLE CHANGE IN
TEMPS/HUMIDITY LEVELS. SUMMERTIME IN FLORIDA.
&&
.MARINE...SE WINDS LESS THAN 15 KT WITH LOW SEAS WILL PREVAIL
THROUGH THU. THE FORECAST FOR FRIDAY AND THIS WEEKEND IS ALL
DEPENDENT ON TS CHANTAL. WINDS/SEAS COULD PICK UP QUITE A BIT OR
REMAIN RATHER LOW...IT JUST ALL DEPENDS ON WHAT TRANSPIRES WITH
CHANTAL. IT IS LOOKING POORLY ORGANIZED AT THE MOMENT.
&&
.FIRE WEATHER...NO CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 76 88 78 / 50 30 50 30
FORT LAUDERDALE 87 79 89 79 / 50 30 50 40
MIAMI 88 77 89 78 / 50 30 50 40
NAPLES 87 73 90 75 / 50 30 50 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...57/GREGORIA
AVIATION/RADAR...60/BD
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
940 PM EDT THU JUL 11 2013
.UPDATE...
MCV CONTINUES TO ROTATE SHOWERS AND THUNDERSTORMS MAINLY ACROSS THE
SOUTHERN TIER OF THE CWA THIS EVENING. CONVECTION SHOULD GRADUALLY
PERTAIN TO THE SOUTHEASTERN PORTION OF THE AREA INTO MORNING...WHILE
THE FRONT PUSHES INTO NORTH GEORGIA. THIS FRONT HAS BEEN TRIGGERING
SOME ISOLATED THUNDERSTORMS AND SHOWERS...THOUGH NOT AS WIDESPREAD
AS IN THE SOUTH. LOCAL WRF AND HRRR SOLUTIONS SUGGEST A BAND OF
CONVECTION MAY DEVELOP AFTER MIDNIGHT FROM THE ATHENS TO ATLANTA
AREA...THOUGH CONFIDENCE IS NOT HIGH IN THIS PLAYING OUT AT THE
MOMENT. THERE IS AN INSTABILITY AXIS NEAR THIS AREA WHICH COULD
SERVE TO FOCUS THE DEVELOPMENT BUT WILL CONTINUE TO WATCH TRENDS.
ALL CONSIDERED...HAVE KEPT LIKELY POPS SOUTHEAST AND CHANCE POPS
ELSEWHERE TONIGHT. HAVE ALSO KEPT CURRENT FLASH FLOOD WATCH SET TO
EXPIRE AT 04Z FOR NORTH GA AND 06Z SOUTH. OTHERWISE MADE ONLY
MINOR TWEAKS TO TEMP...DEWPT...AND SKY TRENDS. PREVIOUS DISCUSSION
FOLLOWS...
BAKER
&&
.PREV DISCUSSION... /ISSUED 818 PM EDT THU JUL 11 2013/
PREV DISCUSSION... /ISSUED 353 PM EDT THU JUL 11 2013/
.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
SHOWERS AND ISOLATED THUNDERSTORMS BEGINNING TO POP ACROSS THE AREA.
MAIN FRONTAL BOUNDARY IS STILL ACROSS TN BUT IT IS MOVING SLOWLY
SOUTH. THIS FRONT SHOULD MOVE INTO NW GA WITHIN THE NEXT FEW
HOURS. THESE SHOWERS AND THUNDERSTORMS ARE STAYING FAIRLY WEAK AND
NOT MOVING VERY MUCH...SO WILL KEEP AN EYE OUT FOR ANY FLOODING
CONCERNS. THERE IS ALSO LESS INSTABILITY ACROSS THE AREA FOR THESE
STORMS TO WORK WITH TODAY SO THEY SHOULD STAY BELOW SEVERE
CRITERIA. THERE MAY BE A STORM OR TWO THAT GETS CLOSE TO SEVERE
NEAR 00Z WHEN THE INSTABILITIES PEAK...SO WILL HAVE TO CONTINUE TO
MONITOR THIS AS WELL. AS THE FRONT MOVES SOUTH IT WILL WILL USHER
IN SOME DRIER AIR AND SHOULD HELP TO KEEP PRECIPITATION DOWN TO A
MINIMUM ESPECIALLY ACROSS NORTH GA FRIDAY. THIS FRONT WILL ALSO
FINALLY PUSH THE MAIN MOISTURE PLUME THAT HAS BEEN OVER THE AREA
FOR THE PAST FEW WEEKS EAST OF THE STATE. THIS DRIER AIR WILL BE
SHORT LIVED AS THE MOISTURE BEGINS TO RETROGRADE WESTWARD SAT
MORNING.
01
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
NO MAJOR CHANGES MADE TO THE EXTENDED PERIODS AS LONG RANGE MODELS
CONTINUE TO SHOW FAIRLY GOOD AGREEMENT WITH A FRONTAL BOUNDARY
LINGERING ACROSS CENTRAL GA ON SATURDAY... THEN PUSHING NORTH AND
SPREADING DEEPER MOISTURE BACK ACROSS NORTH GA ON SUNDAY. AS A
RESULT... EXPECT DECREASED STORM COVERAGE/THREAT ACROSS MUCH OF
NORTH GA ON SATURDAY... WITH SCATTERED AFTERNOON AND EVENING
STORMS STILL LIKELY ACROSS CENTRAL GA NEARER THE FRONT. BUT THIS
CONVECTIVE BREAK ACROSS NORTH GA WILL BE SHORT-LIVED AS RETURNING
DEEP LAYER MOISTURE BEHIND THE ADVANCING WARM-FRONT WILL ALSO
RETURN THE STORM AND POTENTIAL LOCALLY HEAVY RAIN THREAT BACK TO
NORTH GA BY SUNDAY AFTERNOON. THE ECMWF AND GFS SHOW AMAZING
AGREEMENT WITH A LARGE UPPER RIDGING SETTLING OVER THE OHIO VALLEY
REGION BY MONDAY AND HELPING TO FINALLY SHUNT THE DEEPER MOISTURE
AND GREATER STORM THREAT SOUTHWARD INTO SOUTH GA FOR MON-THU.
HOWEVER... STILL EXPECT SUFFICIENT LOW LEVEL MOISTURE AND DAYTIME
INSTABILITIES TO SUPPORT LOW SCATTERED COVERAGE OF AFTERNOON AND
EVENING STORMS EACH DAY. /39
PREV LONG TERM DISCUSSION... /ISSUED 409 AM EDT THU JUL 11 2013/
LONG TERM /SATURDAY THROUGH WEDNESDAY/...
EXTENDED BEGINS WITH CLOSED UPPER LOW VICINITY OF OHIO VALLEY WITH
SOME DRIER AIR ACROSS NORTH GA. GFS/ECMWF DIFFER IN GENERAL
LOCATION OF THE UPPER LOW...BUT BOTH RETROGRADE IT WESTWARD DURING
THE PERIOD. WITH THE UPPER RIDGE LOCATED OFF THE MID ATLANTIC
COAST...THE CWA REMAINS IN AN EASTERLY FLOW OF MOISTURE FROM THE
ATLANTIC. THIS WILL KEEP US IN A PATTERN OF SHOWERS AND
THUNDERSTORMS EACH DAY AND HAVE KEPT MOST POPS IN THE CHANCE
CATEGORY. BY THE END OF THE PERIOD LOOKS LIKE THE UPPER RIDGE
BEGINS TO BUILD BACK OVER THE SOUTHEAST...SO THE PATTERN MAY
BECOME MORE DIURNAL. TWEAKED MAX TEMPERATURES DOWN A BIT MOST DAYS
DUE TO EASTERLY FLOW AND EXPECTED POPS.
&&
.HYDROLOGY...
AS BEEN THE CASE THE PAST SEVERAL DAYS...BASIN-AVERAGE QPF VALUES
ARE NOT PARTICULARLY IMPRESSIVE /BETWEEN 0.5-1 INCH NORTH AND
1-1.5 INCHES SOUTH/...BUT AGAIN THESE ARE BASIN-AVERAGE AND OF
COURSE SOME AREAS WILL GET QUITE A BIT MORE. PW VALUES ARE STILL
RANGING FROM 1.6 TO 2.0 THROUGH 12Z FRI. AS THE FRONT MOVES INTO
THE AREA FORECASTED PW`S DO COME DOWN A BIT FOR FRIDAY. SOME 6-HR
FLASH FLOOD GUIDANCE VALUES ESPECIALLY IN NORTHWEST GEORGIA ARE
LESS THAN AN INCH. SO WITH THAT...WILL KEEP THE FLASH FLOOD WATCH
THROUGH 08Z FRI. WILL ALSO CONTINUE TO KEEP OUR EXTREME SOUTHERN
COUNTIES OUT OF THE WATCH AS THEY CAN HANDLE A BIT MORE PRECIP
THAN AREAS NORTH.
&&
.AVIATION...
00Z UPDATE...
MAINLY VFR CONDITIONS INITIALLY THIS EVENING. SHOWERS AND
THUNDERSTORMS REMAINING ACROSS SOUTHERN SITES WHERE POTENTIAL FOR
LOWER VSBYS REMAINS. CIGS LOOK TO LOWER TO MVFR AND POSSIBLY LOWER
OF 1000-1500 FT AFTER 10Z TONIGHT. SHOULD GRADUALLY INCREASE TO
NEAR 5 KFT WITH SOME SCATTERING OUT BEFORE AFTERNOON MAINLY
ACROSS THE NORTHERN SITES. WINDS WILL BE CALM TO VRB OVERNIGHT AND
SWITCHING TO NE AT LESS THAN 7 KTS 14Z FRIDAY. BEST CHANCE FOR
PRECIP LOOKS TO STAY SE OF KATL AND BE MAINLY FOR KMCN AND KCSG IN
THE AFTERNOON.
//ATL CONFIDENCE...00Z UPDATE...
LOW CONFIDENCE ON MORNING CIGS.
MEDIUM CONFIDENCE ON PRECIP CHANCES FRIDAY.
HIGH CONFIDENCE ALL ELSE.
BAKER
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 70 87 69 84 / 40 40 30 40
ATLANTA 71 87 70 84 / 40 30 20 30
BLAIRSVILLE 66 83 64 80 / 30 20 20 20
CARTERSVILLE 70 87 68 86 / 30 20 20 20
COLUMBUS 73 89 72 88 / 60 40 30 40
GAINESVILLE 70 85 70 81 / 30 30 20 30
MACON 72 87 71 86 / 60 60 40 50
ROME 68 87 67 88 / 40 10 10 20
PEACHTREE CITY 70 87 68 84 / 40 30 20 30
VIDALIA 72 85 71 87 / 60 70 40 50
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 4 AM EDT FRIDAY FOR THE FOLLOWING ZONES:
BALDWIN...BIBB...BUTTS...CHATTAHOOCHEE...CLARKE...CLAYTON...
COWETA...CRAWFORD...FAYETTE...GLASCOCK...GREENE...HANCOCK...
HARRIS...HEARD...HENRY...HOUSTON...JASPER...JEFFERSON...JONES...
LAMAR...MACON...MARION...MERIWETHER...MONROE...MORGAN...
MUSCOGEE...NEWTON...OCONEE...OGLETHORPE...PEACH...PIKE...
PUTNAM...ROCKDALE...SCHLEY...SPALDING...TALBOT...TALIAFERRO...
TAYLOR...TROUP...TWIGGS...UPSON...WALTON...WARREN...WASHINGTON...
WILKES...WILKINSON.
FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR THE FOLLOWING
ZONES: BANKS...BARROW...BARTOW...CARROLL...CATOOSA...CHATTOOGA...
CHEROKEE...COBB...DADE...DAWSON...DEKALB...DOUGLAS...FANNIN...
FLOYD...FORSYTH...GILMER...GORDON...GWINNETT...HALL...HARALSON...
JACKSON...LUMPKIN...MADISON...MURRAY...NORTH FULTON...PAULDING...
PICKENS...POLK...SOUTH FULTON...TOWNS...UNION...WALKER...WHITE...
WHITFIELD.
&&
$$
SHORT TERM...01/BAKER
LONG TERM....39
AVIATION...BAKER
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
721 PM EDT THU JUL 11 2013
.SYNOPSIS...
HIGH PRESSURE CENTERED OFF THE COAST WILL CONTINUE TO CIRCULATE
VERY MOIST AIR INTO THE FORECAST AREA AHEAD OF A COLD FRONT
APPROACHING FROM THE NORTHWEST. THIS FRONT WILL STALL NEAR THE
AREA FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
SHOWERS AND THUNDERSTORMS CONTINUE ACROSS THE AREA EARLY THIS
EVENING. STRONGEST CONVECTION SHIFTING TO THE EASTERN MIDLANDS.
LATEST HRRR GUIDANCE SUGGESTS CONVECTION WILL CONTINUE OVERNIGHT.
SO HEAVY RAIN THREAT CONTINUES. FLASH FLOOD WATCH IN PLACE
THROUGH 4AM FRIDAY MORNING. WITH THE RAINFALL AND EXTENSIVE CLOUD
COVER EXPECTED OVERNIGHT LOWS WILL BE IN THE LOWER 70S.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
WITH PLENTY OF MOISTURE AVAILABLE...CONVERGENCE AHEAD OF THE
APPROACHING COLD FRONT AND A DEEPENING UPPER-LEVEL TROUGH
SUPPORTS NUMEROUS SHOWERS AND THUNDERSTORMS TO ONCE AGAIN DEVELOP
FRIDAY INTO FRIDAY NIGHT. HIGH PRECIPITABLE WATER INDICATES A CONTINUED
THREAT OF EXCESSIVE RAIN AND WITH SLOW MOVING STORMS...URBAN AND
SMALL STREAM FLOODING WILL CONTINUE TO BE LIKELY IN THE AFFECTED AREAS.
THE MODELS SHOW THE FRONT STALLING JUST EAST OF THE FORECAST AREA.
THE TREND OF AFTERNOON THROUGH EVENING THUNDERSTORMS CONTINUES.
TEMPERATURES WILL STAY MAINLY HIGHS IN THE 80S AND LOWS IN THE LOW
70S.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
SATURDAY WILL BE MORE OF THE SAME WITH AFTERNOON SHOWERS AND
THUNDERSTORMS. THE GFS AND ECMWF CONTINUE TO SHOW A MOIST ONSHORE
FLOW. THE GENERAL PATTERN STILL SUPPORTS SCATTERED TO NUMEROUS
SHOWERS AND THUNDERSTORMS WITH THE HIGHER POPS EARLY IN THE
PERIOD. MODELS INDICATE THE UPPER TROUGHING BEGINNING TO SHIFT
WESTWARD BY SUNDAY WITH THE UPPER HIGH NORTH OF THE AREA BECOMING
MORE DOMINATE EARLY NEXT WEEK. WHILE THIS SHOULD RESULT IN A
DECREASE IN PRECIPITABLE WATER AND A DECREASE IN CHANCE OF SHOWERS
AND THUNDERSTORMS...THERE STILL WILL BE A CHANCE OF AFTERNOON
PRECIPITATION INTO EARLY NEXT WEEK. TEMPERATURES ARE EXPECTED TO
BE CLOSER TO NORMAL WITH HIGHS AROUND 90 AND LOWS IN THE LOWER 70S.
&&
.AVIATION /23Z THURSDAY THROUGH TUESDAY/...
THUNDERSTORM THREAT APPEARS TO BE DECREASING AT TERMINALS EXCEPT
OGB FOR THE NEXT FEW HOURS...WHERE CEILINGS AND VISIBILITY MAY BRIEFLY
LOWER TO IFR IN HEAVY RAIN. OTHERWISE MVFR VISIBILITY IN LIGHT
RAIN EXPECTED.
CONVECTION WILL DECREASE IN COVERAGE TONIGHT...HOWEVER SOME
ACTIVITY IS EXPECTED THROUGH THE NIGHT WHICH WILL LIMIT FOG
POTENTIAL. HAVE INCLUDED MVFR CONDITIONS IN FOG AND STRATUS DURING
THE EARLY MORNING HOURS WITH CONDITIONS RETURNING TO VFR WITH
SUNRISE AND ONSET OF MIXING. CONVECTION WILL AGAIN BE POSSIBLE
LATE IN THE TAF PERIOD...HOWEVER CONFIDENCE IS CURRENTLY TOO LOW
TO INCLUDE IN TAFS.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE EACH DAY IN
LATE NIGHT/EARLY MORNING FOG OR STRATUS AS WELL AS SCATTERED
MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...FLASH FLOOD WATCH UNTIL 4 AM EDT FRIDAY FOR SCZ015-016-018-
020>022-025>031-035>038-041.
GA...FLASH FLOOD WATCH UNTIL 4 AM EDT FRIDAY FOR GAZ040-063>065-077.
&&
$$
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
340 PM EDT WED JUL 10 2013
.SYNOPSIS...
BERMUDA HIGH PRESSURE WILL REMAIN OFFSHORE AS A WEAKENING COLD FRONT
APPROACHES THE REGION FROM THE NORTHWEST THROUGH LATE WEEK. THIS
FRONT IS EXPECTED TO STALL OVER OR CLOSE TO THE AREA THIS WEEKEND
AS TROPICAL CYCLONE CHANTAL...OR ITS REMNANTS...APPROACHES THE
SOUTHEAST COAST.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
A WEAK LEE TROUGH AND DEEP MOISTURE PERSIST ACROSS OUR INLAND
AREAS THIS AFTERNOON. RUC ANALYSIS SHOWS PW VALUES ABOVE 2.2
INCHES INLAND WHILE A POCKET OF SOME DRIER 1.8 PW AIR HAS SHIFTED
ONSHORE BEHIND THE SEABREEZE. SFC DEWPOINTS HAVE FLIRTED WITH THE
70 DEGREE MARK AT COASTAL SITES THIS AFTERNOON. EARLIER CONVECTION
ACROSS INLAND SOUTHEAST GA WORKED OVER THE ATMOSPHERE IN THOSE
AREAS AND SINCE THEN WE HAVE SEEN A MARKED DECREASE IN COVERAGE
AND INTENSITY. OUTFLOW BOUNDARIES AND OTHER MESOSCALE INFLUENCES
ARE RESPONSIBLE FOR ISOLATED TO SCATTERED CONVECTION MAINLY ACROSS
INLAND AREAS. WITH THE LOSS OF DAYTIME HEATING WE SHOULD SEE THIS
ACTIVITY FURTHER DIMINISH WITH DRY CONDITIONS OVERNIGHT. LOWS WILL
DROP INTO THE LOWER 70S. OVER THE COASTAL WATERS...SHOWERS AND
TSTMS WILL INCREASE LATE TONIGHT ESPECIALLY OUTER PORTIONS NEAR
THE GULF STREAM.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
THURSDAY AND FRIDAY...HEIGHTS ALOFT WILL BEGIN TO LOWER AS A DEEP
TROUGH OF LOW PRESSURE APPROACHES THE EASTERN SEABOARD...NUDGING
THE UPPER RIDGE FURTHER INTO THE WESTERN ATLANTIC. ALTHOUGH THE
ASSOCIATED COLD FRONT IS EXPECTED TO REMAIN WELL INLAND FROM THE
FORECAST AREA THROUGH FRIDAY...A CONTINUOUS STREAM OF MOISTURE
FROM BOTH THE GULF AND ATLANTIC WILL CONTINUE TO STREAM ABUNDANT
MOISTURE ACROSS THE SOUTHEAST. MODEL SOUNDINGS CAPTURE THIS
INCREASING MOISTURE BY SHOWING PWATS STEADILY CLIMBING TO 2.25
INCHES BY FRIDAY MORNING.
IN REGARDS TO CONVECTION INITIATION ON THURSDAY...EXPECT DECENT
COVERAGE OF SHOWERS AND THUNDERSTORMS BY LATE THURSDAY MORNING ACROSS
WESTERN PORTIONS OF THE CWA. HOWEVER...SLIGHTLY LOWER PWATS ALONG
THE COASTAL AREA COULD DELAY CONVECTION INITIATION FOR AREAS WEST OF
INTERSTATE 95. HOWEVER...STILL EXPECT AT LEAST SCATTERED SHOWERS AND
THUNDERSTORMS TO DEVELOP BY LATE AFTERNOON AS OUTFLOW BOUNDARIES
INTERACT WITH THE SEA BREEZE. THIS TREND WILL CONTINUE INTO FRIDAY
AS THE TROUGH AND ITS ASSOCIATED COLD FRONT NEARS TO FORECAST
AREA...ONLY INCREASING MOISTURE PROFILES. SEVERE POTENTIAL REMAINS
QUITE LIMITED...BUT HEAVY RAINFALL AND THE SATURATED GROUND COULD
LEAD TO LOCALIZED FLOODING.
ON SATURDAY...ANOTHER DAY OF SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS IS EXPECTED AS THE COLD FRONT NEARS AND POSSIBLE
STALLS OVER THE FORECAST AREA. WITH THE POSSIBILITY OF ADDITIONAL
MOISTURE STREAMING ONSHORE FROM TROPICAL CYCLONE CHANTAL...PWATS WILL
REMAIN AROUND 2 INCHES. THE MAIN THREAT REMAINS HEAVY RAINFALL AND
LOCALIZED FLOODING.
IN REGARDS TO TEMPERATURES...EXPECT THURSDAY TO THE BE WARMEST
DAY...WITH TEMPERATURES JUST SHY OF SEASONAL NORMALS...AROUND 90
DEGREES INLAND AND MID 80S ALONG THE COAST. DECENT CLOUD COVERAGE
WILL ONCE AGAIN IMPACT AFTERNOON TEMPERATURES ON FRIDAY AND
SATURDAY...WITH MOST AREAS REMAINING IN THE MID TO UPPER 80S.
OVERNIGHT LOWS WILL DIP INTO THE LOWER 70S INLAND AND MID TO UPPER
70S ALONG THE COAST.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
MAIN FORECAST CHALLENGE FOR THE FIRST PART OF THIS THIS PERIOD IS
WHAT HAPPENS TO TROPICAL STORM CHANTAL. MODEL TRENDS AS OF LATE HAVE
BEEN WEAKER AND MORE DISORGANIZED WITH THE SYSTEM. IF THIS TREND
CONTINUES...THEN THE MAIN IMPACTS MAY BE TO EXTEND THE HEAVY RAIN
THREAT INTO SUNDAY AND PERHAPS SUNDAY NIGHT. PLEASE REFER TO THE
LATEST FORECAST FROM THE NATIONAL HURRICANE CENTER.
LOOKS LIKE A RETURN TO MORE TYPICAL SUMMERTIME WEATHER WILL COMMENCE
STARTING ON MONDAY AND PERSIST INTO AT LEAST WEDNESDAY...WITH HIGHS
MAINLY NEAR 90 AND SCATTERED MAINLY AFTERNOON AND EARLY EVENING
SHOWERS AND THUNDERSTORMS.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL AT KCHS AND KSAV THROUGH
18Z THURSDAY. ISOLATED CONVECTION IS POSSIBLE THIS AFTERNOON AND
THU AFTERNOON BUT MAINLY INLAND FROM THE TERMINALS SO WE AVOIDED
ANY MENTION OF THUNDER IN THE 18Z TAFS.
EXTENDED AVIATION OUTLOOK...LOW PROBABILITIES OF FOG/STRATUS AROUND
SUNRISE EACH MORNING. AT LEAST MODERATE CHANCES FOR DIRECT IMPACTS
FROM MAINLY AFTERNOON/EVENING SHOWERS/THUNDERSTORMS THURSDAY THROUGH
SATURDAY EVENING. LOW CHANCES FOR DIRECT IMPACTS FROM MAINLY
AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS ON SUNDAY AND MONDAY.
&&
.MARINE...
ATLANTIC HIGH PRESSURE WILL MAINTAIN A SOUTHERLY COMPONENT OVER
THE WATERS THROUGH TONIGHT WITH SPEEDS LESS THAN 15 KT.
THURSDAY THROUGH MONDAY...BERMUDA HIGH PRESSURE WILL PREVAIL THROUGH
LATE WEEK PRIOR TO AN APPROACHING COLD FRONT THE WEST. IN
ADDITION...TROPICAL CYCLONE CHANTAL...OR WHAT REMAINS OF
CHANTAL...WILL APPROACH THE GA/SC COASTAL WATERS THIS WEEKEND. THE
PRESSURE GRADIENT BETWEEN THESE SYSTEMS WILL RESULT IN AT LEAST SOME
INCREASE IN WINDS AND SEAS LATE WEEK AND INTO THE WEEKEND.
DUE TO SOME UNCERTAINTY IN REGARD TO TROPICAL CYCLONE CHANTAL...WE
HAVE CAPPED WINDS AT 18 KT AND SEAS AT 8 FEET. HENCE IT DOES APPEAR
QUITE LIKELY THAT SMALL CRAFT ADVISORY CONDITIONS FOR SEAS WOULD BE
NEEDED FOR AT LEAST SOME OF OUR MARINE ZONES...MAINLY SATURDAY AND
SATURDAY NIGHT. MARINERS ARE URGED TO PAY CLOSE ATTENTION TO THE
LATEST FORECASTS.
&&
.HYDROLOGY...
AN APPROACHING COLD FRONT IS EXPECTED TO WEAKEN AND STALL OUT OVER
THE AREA FRIDAY INTO SATURDAY. AHEAD OF THE FRONT DEEP TROPICAL
MOISTURE WILL BE MOVING INTO THE AREA. SLOW STORM MOTIONS AND
TRAINING OF STORMS WILL MEAN THE POTENTIAL FOR HEAVY RAINFALL AND
LOCALIZED FLOODING THURSDAY THROUGH SATURDAY NIGHT...POSSIBLY
LASTING INTO SUNDAY EVENING DEPENDING ON THE THE TRACK OF TROPICAL
CYCLONE CHANTAL.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...JRL
SHORT TERM...JHP
LONG TERM...MTE
AVIATION...JRL
MARINE...JHP/JRL
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1026 AM EDT WED JUL 10 2013
.SYNOPSIS...
HIGH PRESSURE OFF THE SOUTHEAST COAST WILL CIRCULATE A MOIST
SOUTHERLY FLOW INTO THE FORECAST AREA THROUGH THURSDAY. A COLD
FRONT WILL MOVE INTO THE REGION AND STALL FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WEAK SHORT WAVE IN THE CSRA HAS GENERATED MORE SHOWERS AND
THUNDERSTORMS IN THAT REGION. SO...INCREASED POPS TO 60 PERCENT
IN THE CSRA. OTHERWISE...THE LATEST RAP SHOWS AN H7 SHORTWAVE
TROUGH LINGERING OVER THE FORECAST AREA THROUGH 18Z. THE H5 FLOW
APPEARS DIFLUENT. THE MOIST SOUTH FLOW ASSOCIATED WITH THE
OFFSHORE HIGH WILL CONTINUE. EXPECT SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS MAINLY NEAR THE TIME OF MAXIMUM HEATING ALTHOUGH
THE HRRR INDICATES CONSIDERABLE COVERAGE IN THE WEST PART THIS
MORNING. WE HAVE LEANED TOWARD THE HIGHER GUIDANCE POPS. SLOW
STORM MOVEMENT AND PRECIPITABLE WATER AROUND 2 INCHES WILL SUPPORT
VERY HEAVY RAIN IN SOME AREAS. CLOUDINESS AND SHOWERS SHOULD HELP
HOLD DOWN TEMPERATURES. EXPECT HIGHS MAINLY IN THE UPPER 80S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
HIGH PRESSURE OFF THE SOUTHEAST COAST WILL CONTINUE TO CIRCULATE
MOIST AIR INTO THE FORECAST AREA AHEAD OF THE COLD FRONT
APPROACHING FROM THE NORTHWEST. THE NAM AND GFS SHOW THE FRONT
NEAR THE AREA THURSDAY NIGHT. CONVERGENCE AHEAD OF THE FRONT AND
DEEPENING UPPER-LEVEL TROUGHING SHOULD SUPPORT AN INCREASE IN
SHOWER AND THUNDERSTORM COVERAGE. A DIFLUENT 1000-500 MB THICKNESS
PATTERN AND PRECIPITABLE WATER AROUND 2 INCHES INDICATES SLOW
STORM MOVEMENT AND HEAVY RAIN. EXCESSIVE RAIN MAY BECOME AN ISSUE
AND FLASH FLOOD WATCHES OR WARNINGS MAY BE NEEDED. LEANED TOWARD
THE HIGHER GUIDANCE POPS WITH THE GREATER CHANCES NEAR THE TIMES OF
MAXIMUM HEATING. USED THE GUIDANCE CONSENSUS FOR THE TEMPERATURE
FORECAST.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
THE GFS AND ECMWF CONTINUE TO SHOW A MOIST LOW-LEVEL ONSHORE FLOW
DURING MUCH OF THE MEDIUM-RANGE PERIOD. THE MODELS INDICATE UPPER
TROUGHING OVER THE FORECAST AREA BECOMING A CUT-OFF LOW AND
RETROGRADING SATURDAY AND SUNDAY. ANOTHER CUT-OFF LOW APPEARS TO
DEVELOP AND DROP SOUTHWARD TO NEAR THE AREA LATE IN THE PERIOD.
THE EXTENT OF MOISTURE ASSOCIATED WITH CHANTAL IS ALSO A
COMPLICATION. THE GENERAL PATTERN SUPPORTS SCATTERED TO NUMEROUS
SHOWERS AND THUNDERSTORMS WITH HIGH TEMPERATURES COOLER THAN
CLIMATOLOGY.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS THE REST OF TODAY EXCEPT FOR MVFR CIGS IFR VSBYS IN
AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS. MVFR CIGS/VSBYS
POSSIBLE TONIGHT FROM 08Z-13Z.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE EACH DAY IN
LATE NIGHT/EARLY MORNING FOG OR STRATUS AS WELL AS SCATTERED
MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
911 AM EDT WED JUL 10 2013
.SYNOPSIS...
HIGH PRESSURE OFF THE SOUTHEAST COAST WILL CIRCULATE A MOIST
SOUTHERLY FLOW INTO THE FORECAST AREA THROUGH THURSDAY. A COLD
FRONT WILL MOVE INTO THE REGION AND STALL FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WEAK SHORT WAVE IN THE CSRA HAS GENERATED MORE SHOWERS AND
THUNDERSTORMS IN THAT REGION. SO...INCREASED POPS TO 60 PERCENT
IN THE CSRA. OTHERWISE...THE LATEST RAP SHOWS AN H7 SHORTWAVE
TROUGH LINGERING OVER THE FORECAST AREA THROUGH 18Z. THE H5 FLOW
APPEARS DIFLUENT. THE MOIST SOUTH FLOW ASSOCIATED WITH THE
OFFSHORE HIGH WILL CONTINUE. EXPECT SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS MAINLY NEAR THE TIME OF MAXIMUM HEATING ALTHOUGH
THE HRRR INDICATES CONSIDERABLE COVERAGE IN THE WEST PART THIS
MORNING. WE HAVE LEANED TOWARD THE HIGHER GUIDANCE POPS. SLOW
STORM MOVEMENT AND PRECIPITABLE WATER AROUND 2 INCHES WILL SUPPORT
VERY HEAVY RAIN IN SOME AREAS. CLOUDINESS AND SHOWERS SHOULD HELP
HOLD DOWN TEMPERATURES. EXPECT HIGHS MAINLY IN THE UPPER 80S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
HIGH PRESSURE OFF THE SOUTHEAST COAST WILL CONTINUE TO CIRCULATE
MOIST AIR INTO THE FORECAST AREA AHEAD OF THE COLD FRONT
APPROACHING FROM THE NORTHWEST. THE NAM AND GFS SHOW THE FRONT
NEAR THE AREA THURSDAY NIGHT. CONVERGENCE AHEAD OF THE FRONT AND
DEEPENING UPPER-LEVEL TROUGHING SHOULD SUPPORT AN INCREASE IN
SHOWER AND THUNDERSTORM COVERAGE. A DIFLUENT 1000-500 MB THICKNESS
PATTERN AND PRECIPITABLE WATER AROUND 2 INCHES INDICATES SLOW
STORM MOVEMENT AND HEAVY RAIN. EXCESSIVE RAIN MAY BECOME AN ISSUE
AND FLASH FLOOD WATCHES OR WARNINGS MAY BE NEEDED. LEANED TOWARD
THE HIGHER GUIDANCE POPS WITH THE GREATER CHANCES NEAR THE TIMES OF
MAXIMUM HEATING. USED THE GUIDANCE CONSENSUS FOR THE TEMPERATURE
FORECAST.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
THE GFS AND ECMWF CONTINUE TO SHOW A MOIST LOW-LEVEL ONSHORE FLOW
DURING MUCH OF THE MEDIUM-RANGE PERIOD. THE MODELS INDICATE UPPER
TROUGHING OVER THE FORECAST AREA BECOMING A CUT-OFF LOW AND
RETROGRADING SATURDAY AND SUNDAY. ANOTHER CUT-OFF LOW APPEARS TO
DEVELOP AND DROP SOUTHWARD TO NEAR THE AREA LATE IN THE PERIOD.
THE EXTENT OF MOISTURE ASSOCIATED WITH CHANTAL IS ALSO A
COMPLICATION. THE GENERAL PATTERN SUPPORTS SCATTERED TO NUMEROUS
SHOWERS AND THUNDERSTORMS WITH HIGH TEMPERATURES COOLER THAN
CLIMATOLOGY.
&&
.AVIATION /13Z WEDNESDAY THROUGH SUNDAY/...
MODEL TIME SECTIONS SHOW PLENTY OF LOW LEVEL MOISTURE WITH A 10
TO 15 KT LOW LEVEL JET. MVFR CONDITIONS POSSIBLE ACROSS THE AREA
UNTIL 14Z. EXPECT CONDITIONS TO IMPROVE AROUND 14Z. SHOWERS AND
THUNDERSTORMS ARE EXPECTED AGAIN LATER TODAY MAINLY DURING THE
AFTERNOON AND EVENING TIME FRAME WITH RESTRICTIONS POSSIBLE.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE EACH DAY IN
LATE NIGHT/EARLY MORNING FOG OR STRATUS AS WELL AS SCATTERED
MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
644 AM EDT WED JUL 10 2013
.SYNOPSIS...
HIGH PRESSURE OFF THE SOUTHEAST COAST WILL CIRCULATE A MOIST
SOUTHERLY FLOW INTO THE FORECAST AREA THROUGH THURSDAY. A COLD
FRONT WILL MOVE INTO THE REGION AND STALL FRIDAY.
&&
.NEAR TERM /THROUGH TODAY/...
THE LATEST RAP SHOWS AN H7 SHORTWAVE TROUGH LINGERING OVER THE
FORECAST AREA THROUGH 18Z. THE H5 FLOW APPEARS DIFLUENT. THE MOIST
SOUTH FLOW ASSOCIATED WITH THE OFFSHORE HIGH WILL CONTINUE. EXPECT
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS MAINLY NEAR THE
TIME OF MAXIMUM HEATING ALTHOUGH THE HRRR INDICATES CONSIDERABLE
COVERAGE IN THE WEST PART THIS MORNING. WE HAVE LEANED TOWARD THE
HIGHER GUIDANCE POPS. SLOW STORM MOVEMENT AND PRECIPITABLE WATER
AROUND 2 INCHES WILL SUPPORT VERY HEAVY RAIN IN SOME AREAS.
CLOUDINESS AND SHOWERS SHOULD HELP HOLD DOWN TEMPERATURES. EXPECT
HIGHS MAINLY IN THE UPPER 80S.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
HIGH PRESSURE OFF THE SOUTHEAST COAST WILL CONTINUE TO CIRCULATE
MOIST AIR INTO THE FORECAST AREA AHEAD OF THE COLD FRONT
APPROACHING FROM THE NORTHWEST. THE NAM AND GFS SHOW THE FRONT
NEAR THE AREA THURSDAY NIGHT. CONVERGENCE AHEAD OF THE FRONT AND
DEEPENING UPPER-LEVEL TROUGHING SHOULD SUPPORT AN INCREASE IN
SHOWER AND THUNDERSTORM COVERAGE. A DIFLUENT 1000-500 MB THICKNESS
PATTERN AND PRECIPITABLE WATER AROUND 2 INCHES INDICATES SLOW
STORM MOVEMENT AND HEAVY RAIN. EXCESSIVE RAIN MAY BECOME AN ISSUE
AND FLASH FLOOD WATCHES OR WARNINGS MAY BE NEEDED. LEANED TOWARD
THE HIGHER GUIDANCE POPS WITH THE GREATER CHANCES NEAR THE TIMES OF
MAXIMUM HEATING. USED THE GUIDANCE CONSENSUS FOR THE TEMPERATURE
FORECAST.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
THE GFS AND ECMWF CONTINUE TO SHOW A MOIST LOW-LEVEL ONSHORE FLOW
DURING MUCH OF THE MEDIUM-RANGE PERIOD. THE MODELS INDICATE UPPER
TROUGHING OVER THE FORECAST AREA BECOMING A CUT-OFF LOW AND
RETROGRADING SATURDAY AND SUNDAY. ANOTHER CUT-OFF LOW APPEARS TO
DEVELOP AND DROP SOUTHWARD TO NEAR THE AREA LATE IN THE PERIOD.
THE EXTENT OF MOISTURE ASSOCIATED WITH CHANTAL IS ALSO A
COMPLICATION. THE GENERAL PATTERN SUPPORTS SCATTERED TO NUMEROUS
SHOWERS AND THUNDERSTORMS WITH HIGH TEMPERATURES COOLER THAN
CLIMATOLOGY.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
MODEL TIME SECTIONS SHOW PLENTY OF LOW LEVEL MOISTURE WITH A 10
TO 15 KT LOW LEVEL JET. MVFR CONDITIONS POSSIBLE ACROSS THE AREA
UNTIL 14Z. EXPECT CONDITIONS TO IMPROVE AROUND 14Z. SHOWERS AND
THUNDERSTORMS ARE EXPECTED AGAIN LATER TODAY MAINLY DURING THE
AFTERNOON AND EVENING TIME FRAME WITH RESTRICTIONS POSSIBLE.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE EACH DAY IN
LATE NIGHT/EARLY MORNING FOG OR STRATUS AS WELL AS SCATTERED
MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
612 AM EDT WED JUL 10 2013
.SYNOPSIS...
HIGH PRESSURE OFF THE SOUTHEAST COAST WILL CIRCULATE A MOIST
SOUTHERLY FLOW INTO THE FORECAST AREA THROUGH THURSDAY. A COLD
FRONT WILL MOVE INTO THE REGION AND STALL FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE LATEST RAP SHOWS AN H7 SHORTWAVE TROUGH LINGERING OVER THE
FORECAST AREA THROUGH 18Z. THE H5 FLOW APPEARS DIFLUENT. THE
MOIST SOUTH FLOW ASSOCIATED WITH THE OFFSHORE HIGH WILL CONTINUE.
EXPECT SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS MAINLY NEAR
THE TIME OF MAXIMUM HEATING ALTHOUGH THE HRRR INDICATES
CONSIDERABLE COVERAGE IN THE WEST PART THIS MORNING. WE HAVE
LEANED TOWARD THE HIGHER GUIDANCE POPS. SLOW STORM MOVEMENT AND
PRECIPITABLE WATER AROUND 2 INCHES WILL SUPPORT VERY HEAVY RAIN IN
SOME AREAS. CLOUDINESS AND SHOWERS SHOULD HELP HOLD DOWN
TEMPERATURES. EXPECT HIGHS MAINLY IN THE UPPER 80S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
HIGH PRESSURE OFF THE SOUTHEAST COAST WILL CONTINUE TO CIRCULATE
MOIST AIR INTO THE FORECAST AREA AHEAD OF THE COLD FRONT
APPROACHING FROM THE NORTHWEST. THE NAM AND GFS SHOW THE FRONT
NEAR THE AREA THURSDAY NIGHT. CONVERGENCE AHEAD OF THE FRONT AND
DEEPENING UPPER-LEVEL TROUGHING SHOULD SUPPORT AN INCREASE IN
SHOWER AND THUNDERSTORM COVERAGE. A DIFLUENT 1000-500 MB THICKNESS
PATTERN AND PRECIPITABLE WATER AROUND 2 INCHES INDICATES SLOW
STORM MOVEMENT AND HEAVY RAIN. EXCESSIVE RAIN MAY BECOME AN ISSUE
AND FLASH FLOOD WATCHES OR WARNINGS MAY BE NEEDED. LEANED TOWARD
THE HIGH GUIDANCE POPS WITH THE GREATER CHANCES NEAR THE TIMES OF
MAXIMUM HEATING. USED THE GUIDANCE CONSENSUS FOR THE TEMPERATURE
FORECAST.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
THE GFS AND ECMWF CONTINUE TO SHOW A MOIST LOW-LEVEL ONSHORE FLOW
DURING MUCH OF THE MEDIUM-RANGE PERIOD. THE MODELS INDICATE UPPER
TROUGHING OVER THE AREA BECOMING A CUT-OFF LOW AND RETROGRADING
SATURDAY AND SUNDAY. ANOTHER CUT-OFF LOW APPEARS TO DEVELOP AND
DROP SOUTHWARD TO NEAR THE AREA LATE IN THE PERIOD. THE EXTENT OF
MOISTURE ASSOCIATED WITH CHANTAL IS ALSO A COMPLICATION. THE
GENERAL PATTERN SUPPORTS SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS WITH HIGH TEMPERATURES COOLER THAN CLIMATOLOGY.
&&
.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
MODEL TIME SECTIONS SHOW PLENTY OF LOW LEVEL MOISTURE WITH AROUND
A 10 TO 15 KT LOW LEVEL JET. MVFR CONDITIONS POSSIBLE ACROSS THE
AREA UNTIL 14Z. EXPECT CONDITIONS TO IMPROVE BY AROUND 14Z.
SHOWERS AND THUNDERSTORMS ARE EXPECTED AGAIN LATER TODAY MAINLY
DURING THE AFTERNOON AND EVENING TIME FRAME WITH RESTRICTIONS
POSSIBLE.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE EACH DAY IN
LATE NIGHT/EARLY MORNING FOG OR STRATUS AS WELL AS SCATTERED
MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
557 AM EDT WED JUL 10 2013
.SYNOPSIS...
HIGH PRESSURE OFF THE SOUTHEAST COAST WILL CIRCULATE A MOIST
SOUTHERLY FLOW INTO THE FORECAST AREA THROUGH THURSDAY. A COLD
FRONT WILL MOVE INTO THE REGION AND STALL FRIDAY.
&&
.NEAR TERM /THROUGH TODAY/...
THE LATEST RAP SHOWS AN H7 SHORTWAVE TROUGH LINGERING OVER THE
FORECAST AREA THROUGH 18Z. THE H5 FLOW APPEARS DIFLUENT. THE
MOIST SOUTH FLOW ASSOCIATED WITH THE OFFSHORE HIGH WILL CONTINUE.
EXPECT SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS MAINLY NEAR
THE TIME OF MAXIMUM HEATING ALTHOUGH THE HRRR INDICATES
CONSIDERABLE COVERAGE IN THE WEST PART THIS MORNING. WE HAVE
LEANED TOWARD THE HIGHER GUIDANCE POPS. SLOW STORM MOVEMENT AND
PRECIPITABLE WATER AROUND 2 INCHES WILL SUPPORT VERY HEAVY RAIN IN
SOME AREAS. CLOUDINESS AND SHOWERS SHOULD HELP HOLD DOWN
TEMPERATURES. EXPECT HIGHS MAINLY IN THE UPPER 80S.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
HIGH PRESSURE OFF THE SOUTHEAST COAST WILL CONTINUE TO CIRCULATE
MOIST AIR INTO THE FORECAST AREA AHEAD OF THE COLD FRONT
APPROACHING FROM THE NORTHWEST. THE NAM AND GFS SHOW THE FRONT
NEAR THE AREA THURSDAY NIGHT. CONVERGENCE AHEAD OF THE FRONT AND
DEEPENING UPPER-LEVEL TROUGHING SHOULD SUPPORT AN INCREASE IN
SHOWER AND THUNDERSTORM COVERAGE. A DIFLUENT 1000-500 MB THICKNESS
PATTERN AND PRECIPITABLE WATER AROUND 2 INCHES INDICATES SLOW
STORM MOVEMENT AND HEAVY RAIN. EXCESSIVE RAIN MAY BECOME AN ISSUE
AND FLASH FLOOD WATCHES OR WARNINGS MAY BE NEEDED. LEANED TOWARD
THE HIGH GUIDANCE POPS WITH THE GREATER CHANCES NEAR THE TIMES OF
MAXIMUM HEATING. USED THE GUIDANCE CONSENSUS FOR THE TEMPERATURE
FORECAST.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
THE GFS AND ECMWF CONTINUE TO SHOW A MOIST LOW-LEVEL ONSHORE FLOW
DURING MUCH OF THE MEDIUM-RANGE PERIOD. THE MODELS INDICATE UPPER
TROUGHING OVER THE AREA BECOMING A CUT-OFF LOW AND RETROGRADING
SATURDAY AND SUNDAY. ANOTHER CUT-OFF LOW APPEARS TO DEVELOP AND
DROP SOUTHWARD TO NEAR THE AREA LATE IN THE PERIOD. THE EXTENT OF
MOISTURE ASSOCIATED WITH CHANTAL IS ALSO A COMPLICATION. THE
GENERAL PATTERN SUPPORTS SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS WITH HIGH TEMPERATURES COOLER THAN CLIMATOLOGY.
&&
.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
MODEL TIME SECTIONS SHOW PLENTY OF LOW LEVEL MOISTURE WITH AROUND
A 10 TO 15 KT LOW LEVEL JET. MVFR CONDITIONS POSSIBLE ACROSS THE
AREA UNTIL 14Z. EXPECT CONDITIONS TO IMPROVE BY AROUND 14Z.
SHOWERS AND THUNDERSTORMS ARE EXPECTED AGAIN LATER TODAY MAINLY
DURING THE AFTERNOON AND EVENING TIME FRAME WITH RESTRICTIONS
POSSIBLE.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE EACH DAY IN
LATE NIGHT/EARLY MORNING FOG OR STRATUS AS WELL AS SCATTERED
MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
455 AM EDT WED JUL 10 2013
.SYNOPSIS...
HIGH PRESSURE OFF THE SOUTHEAST COAST WILL CIRCULATE A MOIST
SOUTHERLY FLOW INTO THE FORECAST AREA THROUGH THURSDAY. A COLD
FRONT WILL MOVE INTO THE REGION AND STALL FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHOWER ACTIVITY WAS PERSISTING IN THE WEST PART OF THE FORECAST
AREA. THE ACTIVITY APPEARED TO BE MAINLY ASSOCIATED WITH AN H7
SHORTWAVE TROUGH. THE HRRR SHOWED SHOWERS CONTINUING IN THIS AREA
FOR MUCH OF THE MORNING. SLOW STORM MOVEMENT AND PRECIPITABLE
WATER AROUND 2 INCHES MAY SUPPORT VERY HEAVY RAIN IN SOME AREAS.
HEATING SHOULD HELP INCREASE SHOWER AND THUNDERSTORM COVERAGE
THROUGHOUT THE FORECAST AREA DURING THE AFTERNOON WITH A
CONTINUED THREAT OF VERY HEAVY RAIN. WE HAVE LEANED TOWARD THE
HIGHER GUIDANCE POPS. CLOUDINESS AND SHOWERS SHOULD HELP HOLD DOWN
TEMPERATURES. EXPECT HIGHS MAINLY IN THE UPPER 80S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
HIGH PRESSURE OFF THE SOUTHEAST COAST WILL CONTINUE TO CIRCULATE
MOIST AIR INTO THE FORECAST AREA AHEAD OF THE COLD FRONT
APPROACHING FROM THE NORTHWEST. THE NAM AND GFS SHOW THE FRONT
NEAR THE AREA THURSDAY NIGHT. CONVERGENCE AHEAD OF THE FRONT AND
DEEPENING UPPER-LEVEL TROUGHING SHOULD SUPPORT AN INCREASE IN
SHOWER AND THUNDERSTORM COVERAGE. A DIFLUENT 1000-500 MB THICKNESS
PATTERN AND PRECIPITABLE WATER AROUND 2 INCHES INDICATES SLOW
STORM MOVEMENT AND HEAVY RAIN. EXCESSIVE RAIN MAY BECOME AN ISSUE
AND FLASH FLOOD WATCHES OR WARNINGS MAY BE NEEDED. LEANED TOWARD
THE HIGH GUIDANCE POPS WITH THE GREATER CHANCES NEAR THE TIMES OF
MAXIMUM HEATING. USED THE GUIDANCE CONSENSUS FOR THE TEMPERATURE
FORECAST.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
THE GFS AND ECMWF CONTINUE TO SHOW A MOIST LOW-LEVEL ONSHORE FLOW
DURING MUCH OF THE MEDIUM-RANGE PERIOD. THE MODELS INDICATE UPPER
TROUGHING OVER THE AREA BECOMING A CUT-OFF LOW AND RETROGRADING
SATURDAY AND SUNDAY. ANOTHER CUT-OFF LOW APPEARS TO DEVELOP AND
DROP SOUTHWARD TO NEAR THE AREA LATE IN THE PERIOD. THE EXTENT OF
MOISTURE ASSOCIATED WITH CHANTAL IS ALSO A COMPLICATION. THE
GENERAL PATTERN SUPPORTS SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS WITH HIGH TEMPERATURES COOLER THAN CLIMATOLOGY.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
PERSISTENT SHOWERS CONTINUE OVER PORTIONS OF THE WESTERN MIDLANDS
AND THE CSRA. HAVE MENTION VCSH/SHRA AGS/DNL UNTIL AROUND 11Z.
THE POTENTIAL FOR EARLY MORNING FOG IS THE NEXT AREA OF CONCERN.
MODEL TIME SECTIONS SHOW PLENTY OF LOW LEVEL MOISTURE WITH AROUND
A 10 TO 15 KT LOW LEVEL JET. MVFR CONDITIONS POSSIBLE ACROSS THE
AREA UNTIL 14Z. EXPECT CONDITIONS TO IMPROVE BY AROUND 14Z.
SHOWERS AND THUNDERSTORMS ARE EXPECTED AGAIN LATER TODAY MAINLY
DURING THE AFTERNOON AND EVENING TIME FRAME WITH RESTRICTIONS
POSSIBLE.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE EACH DAY IN
LATE NIGHT/EARLY MORNING FOG OR STRATUS AS WELL AS SCATTERED
MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
414 AM EDT WED JUL 10 2013
.SYNOPSIS...
HIGH PRESSURE OFF THE SOUTHEAST COAST WILL CIRCULATE A MOIST
SOUTHERLY FLOW INTO THE FORECAST AREA THROUGH THURSDAY. A COLD
FRONT WILL MOVE INTO THE REGION AND STALL FRIDAY.
&&
.NEAR TERM /THROUGH TODAY/...
SHOWER ACTIVITY WAS PERSISTING IN THE WEST PART OF THE FORECAST
AREA. THE ACTIVITY APPEARED TO BE MAINLY ASSOCIATED WITH AN H7
SHORTWAVE TROUGH. THE HRRR SHOWED SHOWERS CONTINUING IN THIS AREA
FOR MUCH OF THE MORNING. SLOW STORM MOVEMENT AND PRECIPITABLE
WATER AROUND 2 INCHES MAY SUPPORT VERY HEAVY RAIN IN SOME AREAS.
HEATING SHOULD HELP INCREASE SHOWER AND THUNDERSTORM COVERAGE
THROUGHOUT THE FORECAST AREA DURING THE AFTERNOON WITH A
CONTINUED THREAT OF VERY HEAVY RAIN. WE HAVE LEANED TOWARD THE
HIGHER GUIDANCE POPS. CLOUDINESS AND SHOWERS SHOULD HELP HOLD DOWN
TEMPERATURES. EXPECT HIGHS MAINLY IN THE UPPER 80S.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
HIGH PRESSURE OFF THE SOUTHEAST COAST WILL CONTINUE TO CIRCULATE
MOIST AIR INTO THE FORECAST AREA AHEAD OF THE COLD FRONT
APPROACHING FROM THE NORTHWEST. THE NAM AND GFS SHOW THE FRONT
NEAR THE AREA THURSDAY NIGHT. CONVERGENCE AHEAD OF THE FRONT AND
DEEPENING UPPER-LEVEL TROUGHING SHOULD SUPPORT AN INCREASE IN
SHOWER AND THUNDERSTORM COVERAGE. A DIFLUENT 1000-500 MB THICKNESS
PATTERN AND PRECIPITABLE WATER AROUND 2 INCHES INDICATES SLOW
STORM MOVEMENT AND HEAVY RAIN. EXCESSIVE RAIN MAY BECOME AN ISSUE
AND FLASH FLOOD WATCHES OR WARNINGS MAY BE NEEDED. LEANED TOWARD
THE HIGH GUIDANCE POPS WITH THE GREATER CHANCES NEAR THE TIMES OF
MAXIMUM HEATING. USED THE GUIDANCE CONSENSUS FOR THE TEMPERATURE
FORECAST.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
THE GFS AND ECMWF CONTINUE TO SHOW A MOIST LOW-LEVEL ONSHORE FLOW
DURING MUCH OF THE MEDIUM-RANGE PERIOD. THE MODELS INDICATE UPPER
TROUGHING OVER THE AREA BECOMING A CUT-OFF LOW AND RETROGRADING
SATURDAY AND SUNDAY. ANOTHER CUT-OFF LOW APPEARS TO DEVELOP AND
DROP SOUTHWARD TO NEAR THE AREA LATE IN THE PERIOD. THE EXTENT OF
MOISTURE ASSOCIATED WITH CHANTAL IS ALSO A COMPLICATION. THE
GENERAL PATTERN SUPPORTS SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS WITH HIGH TEMPERATURES COOLER THAN CLIMATOLOGY.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
PERSISTENT SHOWERS WITH EMBEDDED THUNDERSTORMS CONTINUE OVER
PORTIONS OF THE WESTERN MIDLANDS AND MUCH OF THE CSRA. HAVE MENTIONS
VCTS/TSRA AT AGS/DNL UNTIL AROUND 07Z. THE POTENTIAL FOR LATE
NIGHT/EARLY MORNING FOG IS THE NEXT AREA OF CONCERN. MODEL TIME
SECTIONS SHOW PLENTY OF LOW LEVEL MOISTURE WITH AROUND A 10 TO 15
KT LOW LEVEL JET. CONTINUED TO INDICATE MVFR CONDITIONS DEVELOPING
AT OGB/AGS/DNL AFTER 08Z. HOWEVER...CONDITIONS COULD BE EVEN
LOWER...BUT WILL NOT GO IFR AT THOSE SITES AT THIS TIME AS
CONFIDENCE NOT THAT HIGH. VISIBILITIES AT CAE/CUB ALREADY DROPPED
TO 9SM...SO HINTED AT THEM GOING LOWER BUT KEPT THEM VFR FOR NOW.
EXPECT CONDITIONS TO IMPROVE BY AROUND 14Z. SHOWERS AND
THUNDERSTORMS ARE EXPECTED AGAIN ON WEDNESDAY MAINLY DURING THE
AFTERNOON AND EVENING TIME FRAME WITH RESTRICTIONS POSSIBLE.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE EACH DAY IN
LATE NIGHT/EARLY MORNING FOG OR STRATUS AS WELL AS SCATTERED
MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
308 AM EDT WED JUL 10 2013
.SYNOPSIS...
HIGH PRESSURE OFF THE SOUTHEAST COAST WILL CIRCULATE A MOIST
SOUTHERLY FLOW INTO THE FORECAST AREA THROUGH THURSDAY. A COLD
FRONT WILL MOVE INTO THE REGION AND STALL FRIDAY.
&&
.NEAR TERM /THROUGH TODAY/...
SHOWER AND THUNDERSTORM ACTIVITY WAS PERSISTING IN THE WEST PART
OF THE FORECAST AREA. THE ACTIVITY APPEARED TO BE MAINLY
ASSOCIATED WITH AN H7 SHORTWAVE TROUGH. THE HRRR SHOWED SHOWERS
CONTINUING IN THIS AREA FOR MUCH OF THE MORNING. SLOW STORM
MOVEMENT AND PRECIPITABLE WATER AROUND 2 INCHES WILL SUPPORT VERY
HEAVY RAIN IN SOME AREAS. HEATING SHOULD HELP INCREASE SHOWER AND
THUNDERSTORM COVERAGE IN THE REST OF THE FORECAST AREA DURING THE
AFTERNOON WITH A CONTINUED THREAT OF VERY HEAVY RAIN. WE HAVE
LEANED TOWARD THE HIGH GUIDANCE POPS. CLOUDINESS AND SHOWERS
SHOULD HELP HOLD DOWN TEMPERATURES. EXPECT HIGHS MAINLY IN THE
UPPER 80S.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
HIGH PRESSURE OFF THE SOUTHEAST COAST WILL CONTINUE TO CIRCULATE
MOIST AIR INTO THE FORECAST AREA AHEAD OF THE COLD FRONT
APPROACHING FROM THE NORTHWEST. THE NAM AND GFS SHOW THE FRONT
NEAR THE AREA THURSDAY NIGHT. CONVERGENCE AHEAD OF THE FRONT AND
DEEPENING UPPER-LEVEL TROUGHING SHOULD SUPPORT AN INCREASE IN
SHOWER AND THUNDERSTORM COVERAGE. A DIFLUENT 1000-500 MB
THICKNESS PATTERN AND PRECIPITABLE WATER AROUND 2 INCHES INDICATES
SLOW STORM MOVEMENT AND HEAVY RAIN. EXCESSIVE RAIN MAY BECOME AN
ISSUE AND FLASH FLOOD WATCHES OR WARNINGS MAY BE NEEDED. LEANED
TOWARD THE HIGH GUIDANCE POPS WITH THE GREATER CHANCES NEAR THE
TIMES OF MAXIMUM HEATING. USED THE GUIDANCE CONSENSUS FOR THE
TEMPERATURE FORECAST.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
THE GFS AND ECMWF CONTINUE TO SHOW A MOIST LOW-LEVEL ONSHORE FLOW
DURING MUCH OF THE MEDIUM-RANGE PERIOD. THE MODELS INDICATE UPPER
TROUGHING OVER THE AREA BECOMING A CUT-OFF LOW AND RETROGRADING
SATURDAY AND SUNDAY. THERE ARE DIFFERENCES LATER IN THE PERIOD
WITH THE GFS SHOWING ANOTHER UPPER LOW OVER THE FORECAST AREA LATE
IN THE PERIOD. THE EXTENT OF MOISTURE ASSOCIATED WITH CHANTAL IS
ALSO A COMPLICATION. THE GENERAL PATTERN SUPPORTS SCATTERED TO
NUMEROUS SHOWERS AND THUNDERSTORMS WITH HIGH TEMPERATURES COOLER
THAN CLIMATOLOGY.
&&
.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
PERSISTENT SHOWERS WITH EMBEDDED THUNDERSTORMS CONTINUE OVER
PORTIONS OF THE WESTERN MIDLANDS AND MUCH OF THE CSRA. HAVE MENTIONS
VCTS/TSRA AT AGS/DNL UNTIL AROUND 07Z. THE POTENTIAL FOR LATE
NIGHT/EARLY MORNING FOG IS THE NEXT AREA OF CONCERN. MODEL TIME
SECTIONS SHOW PLENTY OF LOW LEVEL MOISTURE WITH AROUND A 10 TO 15
KT LOW LEVEL JET. CONTINUED TO INDICATE MVFR CONDITIONS DEVELOPING
AT OGB/AGS/DNL AFTER 08Z. HOWEVER...CONDITIONS COULD BE EVEN
LOWER...BUT WILL NOT GO IFR AT THOSE SITES AT THIS TIME AS
CONFIDENCE NOT THAT HIGH. VISIBILITIES AT CAE/CUB ALREADY DROPPED
TO 9SM...SO HINTED AT THEM GOING LOWER BUT KEPT THEM VFR FOR NOW.
EXPECT CONDITIONS TO IMPROVE BY AROUND 14Z. SHOWERS AND
THUNDERSTORMS ARE EXPECTED AGAIN ON WEDNESDAY MAINLY DURING THE
AFTERNOON AND EVENING TIME FRAME WITH RESTRICTIONS POSSIBLE.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE EACH DAY IN
LATE NIGHT/EARLY MORNING FOG OR STRATUS AS WELL AS SCATTERED
MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
300 PM CDT THU JUL 11 2013
.DISCUSSION...
ISSUED 300 PM CDT THU JUL 11 2013
12Z SHORT RANGE MODELS ARE IN GOOD AGREEMENT THROUGH SAT NIGHT AS FAIR
WEATHER PREVAILS ACROSS IL. LIKE THE 00Z MODEL SUITE...THE NEW 12Z
MODELS DEVELOP CUTOFF UPPER LEVEL LOW NEAR OH/WV BY FRI MORNING
AND RETROGRADE IT SW INTO THE MID MS VALLEY BY SAT EVENING...INTO
THE OZARKS SUNDAY MORNING AND CENTRAL PLAINS SUN NIGHT/MON.
MEANWHILE STRONG UPPER LEVEL RIDGE (597 DM) SHIFTS WEST FROM THE
MID ATLANTIC STATES INTO THE OHIO VALLEY BY MIDDLE OF NEXT WEEK.
MODELS SHOWER SOME QPF FIELD OVER PARTS OF CENTRAL/SE IL DURING NEXT
WEEK AND DIURNALLY ENHANCED DURING AFTERNOON/EARLY EVENING HOURS
WITH INCREASING HEAT AND HUMIDITY. WILL ADD SLIGHT CHANCES OF
CONVECTION DURING AFTERNOON/EVENING HOURS NEXT WEEK BUT STILL
THINK COVERAGE LIMITED IF IT OCCURS DUE TO LACKING LIFTING
MECHISMS OUTSIDE OF UPPER LEVEL LOW PASSING TO OUR SOUTH SAT NIGHT.
SHORT TERM...TODAY THROUGH SUNDAY NIGHT
WEAK 1020 MB HIGH PRESSURE LAKE MI AND RIDGING SW INTO NORTHERN MO
AND WEST CENTRAL IL TO STRENGTHEN TO AROUND 1025 MB AS IT DRIFTS
EAST INTO NEW ENGLAND BY SAT MORNING AND STILL RIDGING SW BACK
INTO IL. THIS SHOULD CONTINUE FAIR WEATHER OVER CENTRAL/SE IL WITH
A FAIR AMOUNT OF SUNSHINE AND MORE COMFORTABLE TEMPS AND HUMIDITY
LEVELS AS WE ARE ENJOYING TODAY. SCATTERED CUMULUS CLOUDS FROM IL
RIVER SE WILL DISSIPATE BY SUNSET LEAVING CLEAR SKIES TONIGHT.
LOWS GET CLOSE TO DEWPOINTS IN THE MID TO UPPER 50S WITH LIGHT NE
WINDS. MODELS SHOW LESS CUMULUS CLOUDS AROUND ON FRIDAY WITH DRIER
AIRMASS IN PLACE SO SHOULD NEARLY SUNNY SKIES FRIDAY WITH HIGHS IN
THE LOWER 80S AND COMFORTABLE DEWPOINTS IN THE MID TO UPPER 50S.
FAIR SKIES EXPECTED FRI NIGHT WITH LIGHT EAST WINDS AND LOWS IN
THE UPPER 50S TO NEAR 60F. SCATTERED CUMULUS TO DEVELOP BY SAT
AFTERNOON ESPECIALLY OVER EASTERN/SE IL WITH MOSTLY SUNNY SKIES
OVERALL. HIGHS IN THE MID 80S WITH DEWPOINTS IN THE LOWER 60S.
UPPER LEVEL LOW TO RETROGRADE INTO THE MID MS VALLEY BY SAT
EVENING AND THINK MOISTURE STILL LIMITED OVER CENTRAL IL TO STAY
DRY INTO SUNDAY. COULD BE ISOLATED CONVECTION NEAR THE WABASH
RIVER SUNDAY AFTERNOON WHERE BETTER MOISTURE IN PLACE AND
DEWPOINTS ELEVATE INTO THE MID TO UPPER 60S. HIGHS SUNDAY IN THE
MID TO UPPER 80S.
LONG TERM...MONDAY TRHOUGH THURSDAY
EXTENDED MODELS TRACK UPPER LEVEL LOW INTO THE CENTRAL PLAINS
SUNDAY NIGHT/MON AND WEAKEN IT BY MIDDLE OF NEXT WEEK AS UPPER
LEVEL HIGH PRESSURE RIDGE AROUND 597 DM RETROGRADES WEST FROM THE
MID ALTANTIC STATES INTO THE OHIO VALLEY BY MIDDLE OF NEXT WEEK.
INCREASING INSTABILITY WITH DEWPOINTS IN THE LOWER 70S AND HIGHS
IN THE UPPER 80S TO NEAR 90F TO DEVELOP ISOLATED CONVECTION EACH
AFTERNOON UNTIL SUNSET ESPECIALLY OVER EASTERN/SE IL WHERE CAP IS
WEAKER. THINK IL RIVER VALLEY IS STILL DRY YET ON MONDAY BUT HAVE
SLIGHT CHANCE ACROSS AREA FROM TUE THROUGH THU.
07
&&
.AVIATION...
ISSUED 1230 PM CDT THU JUL 11 2013
VFR CONDITIONS WITH NO MAJOR AVIATION CONCERNS CAN BE EXPECTED
FOR THE NEXT 24 HOURS.
HIGHER MOISTURE NEAR GROUND LEVEL...WEAK INSTABILITY AND
TEMPERATURES IN THE 75 TO 80 RANGE HAS RESULTED IN SCATTERED
CUMULUS AROUND 5 KFT EARLY THIS AFTERNOON IN CENTRAL IL. THE LOW
LEVEL GFS RH FIELD AND TO A CERTAIN EXTENT THE HRRR CLOUD BASE
FORECAST ARE DOING A FAIR JOB OF KEEPING THE SCT CLOUDS IN THE
REGION THIS AFTERNOON. LOSS OF DAYTIME HEATING AND ADVECTION OF
DRIER AIR WILL RESULT IN A CLEAR SKY AN HOUR OR TWO BEFORE SUNSET.
HIGH PRESSURE IN SW WISCONSIN WILL SLOWLY DRIFT TOWARD SE
WISCONSIN BY DAYBREAK FRIDAY. THIS WILL PUT CENTRAL IL IN THE
SURFACE RIDGE AXIS OVERNIGHT...RESULTING A VERY LIGHT WIND AND
CLEAR SKY. LOWERING DEW POINTS SHOULD KEEP ANY LIGHT FOG FROM
FORMING OVERNIGHT.
MILLER
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1230 PM 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.
&&
.AVIATION...
ISSUED 1230 PM CDT THU JUL 11 2013
VFR CONDITIONS WITH NO MAJOR AVIATION CONCERNS CAN BE EXPECTED
FOR THE NEXT 24 HOURS.
HIGHER MOISTURE NEAR GROUND LEVEL...WEAK INSTABILITY AND
TEMPERATURES IN THE 75 TO 80 RANGE HAS RESULTED IN SCATTERED
CUMULUS AROUND 5 KFT EARLY THIS AFTERNOON IN CENTRAL IL. THE LOW
LEVEL GFS RH FIELD AND TO A CERTAIN EXTENT THE HRRR CLOUD BASE
FORECAST ARE DOING A FAIR JOB OF KEEPING THE SCT CLOUDS IN THE
REGION THIS AFTERNOON. LOSS OF DAYTIME HEATING AND ADVECTION OF
DRIER AIR WILL RESULT IN A CLEAR SKY AN HOUR OR TWO BEFORE SUNSET.
HIGH PRESSURE IN SW WISCONSIN WILL SLOWLY DRIFT TOWARD SE
WISCONSIN BY DAYBREAK FRIDAY. THIS WILL PUT CENTRAL IL IN THE
SURFACE RIDGE AXIS OVERNIGHT...RESULTING A VERY LIGHT WIND AND
CLEAR SKY. LOWERING DEW POINTS SHOULD KEEP ANY LIGHT FOG FROM
FORMING OVERNIGHT.
MILLER
&&
.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 DEW POINTS 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 DEW POINTS BACK INTO THE LOWER 70S
BY MONDAY.
BARNES
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
248 PM CDT WED JUL 10 2013
.DISCUSSION...
305 AM CDT
FORECAST CHALLENGES THIS WEDNESDAY MORNING INCLUDE STILL AWAITING
THE ARRIVAL OF CONVECTION. JOKING ASIDE...IT IS IMPRESSIVE TO GET
THROUGH THIS VERY HIGH PWAT AND UNSTABLE AIR ALOFT /MUCAPES
2000-3500 J/KG/ WITHOUT CONVECTION FROM MIDDAY YESTERDAY THROUGH
LAST NIGHT. IT REMINDED HOW IMPORTANT THE TIMING OF A TRIGGER OR
SOME FORM OF FOCI ARE FOR CONVECTION...OR INHIBITING DEVELOPMENT IF
IN THE WAKE OF SUCH FEATURES. BUT BACK TO THE CHALLENGES GOING
FORWARD...THERE IS A CHANCE FOR CONVECTION THIS MORNING SOUTH OF
I-80 AS THE SURFACE TROUGH /A FOCUS!/ TAPS THE LAST OF THE MOIST AND
UNSTABLE AIR. THEN ATTENTION TURNS TO HOW QUICKLY TEMPERATURES WILL
WARM AFTER THE SEASONAL AIR ON THU AND FRI.
THIS MORNING...WELL-DEFINED UPPER TROUGH ACROSS WESTERN ONTARIO TO
NORTHERN IA IS PROGRESSING ESE. THE SURFACE TROUGH EXTENDS FROM A
1000MB LOW IN EASTERN ONTARIO TO THE QUAD CITIES AT 3 AM THIS
MORNING. DEW POINTS IN THE MID 70S ARE POOLED ACROSS THE AREA
OFFERING A MUGGY START TO THE DAY. SCATTERED ACCAS IS SEEN ON IR IN
THE REGION BUT NO SIGNS ON RADAR OR SATELLITE OF THIS DEVELOPING. A
SHORT WAVE IMPULSE SEEN ON WATER VAPOR AND 700MB PROFILER ANALYSIS
IS TRAVERSING SOUTHERN IA/NORTHERN MO...BASICALLY ALONG THE BASE
OF THE PRIMARY TROUGH. WHILE CONVECTIVE ALLOWING GUIDANCE SUCH AS
THE HRRR DOES HAVE CONVECTIVE DEVELOPMENT TRAVERSING THE FAR
SOUTHERN FORECAST AREA WITH THIS AND ALONG THE SURFACE BOUNDARY
DURING MID-MORNING...RADAR TRENDS SHOW SUBTLE ECHOES FURTHER SOUTH.
THE LOW-LEVEL JET HAS VEERED AND THE MORE SUBSTANTIAL MOISTURE
TRANSPORT HAS ALSO ENDED EARLY THIS MORNING...SO NOT SEEING TOO MUCH
HAPPENING. SO ONLY MAINTAINED LOW T-STORM CHANCES IN THE SOUTHERN
FORECAST AREA.
THIS AFTERNOON INTO TONIGHT...SUBSTANTIAL COLUMN DRYING IS FORECAST
AS THE AFTERNOON PROGRESSES. SURFACE DEW POINTS WILL FALL SLOWLY
THROUGH THE 60S AND WILL LIKELY STILL SUPPORT AT LEAST FEW AND
POTENTIALLY SCATTERED CU. THE 850MB TEMPERATURES IN THE MID-UPPER
TEENS FORECAST AT 18Z ACROSS THE FORECAST AREA...ALONG WITH THE WARM
STARTING POINT FOR TEMPERATURES...INDICATE MANY COMMUNITIES
REACHING THE MID AND POTENTIALLY UPPER 80S. AREAS NEAR THE WI STATE
LINE ARE MORE LIKELY TO FLAT-LINE IN TEMPERATURES THIS AFTERNOON AS
THE COOL FRONT PORTION OF THIS TROUGH WORKS THROUGH. NORTHWEST WINDS
IN THE BOUNDARY LAYER WILL BE RIGHT AT THE CUSP AT KEEPING A LAKE
BREEZE AT BAY FOR CHICAGO BUT SOME COOLING OF SEVERAL DEGREES COULD
BE SEEN BY MID-AFTERNOON IMMEDIATELY NEAR THE IL LAKESHORE AND
DEFINITELY NEAR THE IN SHORE.
THURSDAY THROUGH FRIDAY...A QUIET TIME AS SURFACE HIGH PRESSURE ON
THE ORDER OF 1019 MB MOVES ATOP THE AREA. THERE SHOULD BE LIMITED
CIRRUS AND ONLY FEW CU DURING THE AFTERNOONS. A MODEL BLEND
TYPICALLY DOES VERY WELL FOR TEMPS IN THIS TYPE OF CALM REGIME AND
HAVE BLENDED THAT WITH GOING FORECAST. TEMPERATURES SHOULD BE
WITHIN A COUPLE DEGREES OF OR RIGHT AT NORMAL.
THIS WEEKEND INTO EARLY NEXT WEEK...THE TREND IN LONG RANGE GUIDANCE
CONTINUES TO POINT TOWARD A WARMER AND DRIER TIME THAN SOLUTIONS
FROM A COUPLE DAYS AGO WITH STOUT UPPER RIDGING FROM THE WEST
SOUTHWEST STRETCHING OVER THE AREA. THE ADVANCING RIDGE FROM THE
WEST LATE THIS WEEK GETS HELD UP WITH BOTH A CLOSED LOW IN THE
NORTHEAST/MID-ATLANTIC AND TROPICAL STORM CHANTAL...FORECAST BY NHC
TO BE NEAR THE GA/SC SHORE BY LATE SUNDAY. 500MB HEIGHTS IN EXCESS
OF 594DM ARE FORECAST BY BOTH THE EC AN GFS FOR THE WEEKEND. WHILE
THE EC WEAKENS THIS MORE THAN THE GFS EARLY NEXT WEEK...THE PATTERN
FORECAST IS STILL BLOCKED AND RIDGE RIDING ACTIVITY IS FORECAST FOR
MOST OF THIS TIME FAIRLY FAR NORTH. BUT AS WE SAW IN THE JUNE 22-26
STRETCH...THAT CAN EVOLVE FURTHER SOUTH THAN LONG RANGE SOLUTIONS
SHOW AS MULTIPLE ROUNDS OF CONVECTION FIRE. BUT THIS IS CERTAINLY A
STRONGER RIDGE FORECAST THIS FAR NORTHEAST. THE 850MB 20C TEMP
CONTOUR FLIRTS WITH THE CWA ON BOTH SOLUTIONS FROM SAT THROUGH TUE.
HAVE BOOSTED TEMPS A COUPLE DEGREES FURTHER AND IF THAT THERMAL
RIDGE ENDS UP FURTHER SOUTH UNCONTAMINATED WITH CONVECTIVE
CLOUDS...CAN CERTAINLY ENVISION AT LEAST LOW 90S AWAY FROM THE LAKE
FOR MULTIPLE DAYS. BUT CONFIDENCE ENVELOPE...WHILE NOT OVERLY
LARGE...IS CENTERED MORE ON UPPER 80S /LOW-MID NEAR THE LAKE/. THE
EASTERN ATLANTIC/GULF FLOW LOOKS TO RETURN HIGHER DEW POINTS BY SUN
OR MON.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* NORTHEAST WINDS EXPECTED AT MDW...BUT LAKE BREEZE BOUNDARY HAS
STALLED EAST OF ORD WITH NORTH-NORTHWEST WINDS CONTINUING THERE.
KJB
//DISCUSSION...UPDATED 20Z...
IT APPEARS THAT THE LAKE BREEZE BOUNDARY MAY STRUGGLE TO GET
THROUGH ORD THIS AFTERNOON. RADAR TRENDS INDICATE IT TO BE STALLED
AROUND 2 TO 3 MILES EAST OF THE TERMINAL. THERE IS STILL A LOW
CHANCE OF IT MAKING A SURGE WESTWARD. HOWEVER...IT APPEARS THAT
THE GUSTY NORTHWEST WINDS WEST OF THE BOUNDARY HAVE HALTED ITS
WESTWARD PROGRESS. THE NEW TAF UPDATE HAS PULLED THE MENTION OF A
WIND SHIFT AT ORD.
//DISCUSSION...UPDATED 18Z...
THE WEATHER PATTERN IS QUIETING DOWN ACROSS THE REGION AS A COLD
FRONT CONTINUES TO SHIFT SOUTH ACROSS ILLINOIS AND INDIANA EARLY
THIS AFTERNOON. ASIDE FROM SOME SCT TO OCCASIONALLY BKN CIGS AROUND
4000 FEET...SKIES SHOULD REMAIN FAIRLY CLEAR...ESPECIALLY TONIGHT.
THE WINDS WILL BE THE MAIN ISSUE THIS AFTERNOON. LOCAL RADAR
DATA...ALONG WITH AREA SURFACE OBSERVATIONS INDICATE THAT THE LAKE
BREEZE BOUNDARY REMAINS DRAPED FROM NORTH TO SOUTH ACROSS EASTERN
COOK COUNTY ABOUT 5 TO 10 MILES EAST OF THE TERMINALS. THE BOUNDARY
DOES APPEAR TO BE MOVING SLOWLY WESTWARD...AND IT STILL APPEARS THAT
A WIND SHIFT MAY OCCUR AT THE TERMINALS OVER THE NEXT 1 TO 2 HOURS.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM CONFIDENCE WITH THE LAKE BREEZE BOUNDARY REMAINING EAST
OF ORD.
KJB
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR.
FRIDAY...VFR.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...VFR.
TUESDAY...VFR.
RODRIGUEZ
&&
.MARINE...
240 PM CDT
HIGH PRESSURE OVER THE CENTRAL AND NORTHERN PLAINS WILL BE SPREADING
EASTWARD ACROSS LAKE MICHIGAN THURSDAY AND BE OVERHEAD OF THE LAKE
BY FRIDAY. THIS WILL KEEP RATHER LIGHT NORTHERLY WINDS ACROSS THE
LAKE TONIGHT AND EARLY THURSDAY BUT THE FLOW WILL LIKELY BE LIGHT
ENOUGH TO ONSHORE FLOW TO DEVELOP AROUND THE LAKE THURSDAY
AFTERNOON. A SIMILAR SET UP MAY OCCUR FRIDAY WITH THE HIGH
OVERHEAD. THE MAIN LOW PRESSURE TRACK WILL BE ACROSS SOUTHERN
CANADA AND A TROUGH DOES MOVE ACROSS THE CANADIAN PRAIRIES FRIDAY
WHICH WILL HELP PUSH THE HIGH EASTWARD AND TIGHTEN UP THE PRESSURE
GRADIENT SOMEWHAT ACROSS THE NORTHERN PART OF THE LAKE GOING INTO
SATURDAY. WITH THE HIGH TO THE EAST A STEADIER SOUTH TO SOUTHWEST
DIRECTION WILL DEVELOP BUT ONSHORE FLOW/LAKE BREEZE DOES LOOK TO
DEVELOP ACROSS THE SOUTHERN SHORELINES AGAIN SATURDAY. SOUTHERLY
FLOW WILL CONTINUE OVER THE WEEKEND WITH THE BEST PRESSURE
GRADIENT ACROSS THE NORTH. A FRONTAL BOUNDARY WILL APPROACH THE
U.P. OF MICHIGAN BY SUNDAY AND MAY LEAD TO INCREASED THUNDERSTORM
POTENTIAL SUNDAY THROUGH MONDAY AS IT SAGS SOUTHWARD.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1255 PM CDT WED JUL 10 2013
.DISCUSSION...
305 AM CDT
FORECAST CHALLENGES THIS WEDNESDAY MORNING INCLUDE STILL AWAITING
THE ARRIVAL OF CONVECTION. JOKING ASIDE...IT IS IMPRESSIVE TO GET
THROUGH THIS VERY HIGH PWAT AND UNSTABLE AIR ALOFT /MUCAPES
2000-3500 J/KG/ WITHOUT CONVECTION FROM MIDDAY YESTERDAY THROUGH
LAST NIGHT. IT REMINDED HOW IMPORTANT THE TIMING OF A TRIGGER OR
SOME FORM OF FOCI ARE FOR CONVECTION...OR INHIBITING DEVELOPMENT IF
IN THE WAKE OF SUCH FEATURES. BUT BACK TO THE CHALLENGES GOING
FORWARD...THERE IS A CHANCE FOR CONVECTION THIS MORNING SOUTH OF
I-80 AS THE SURFACE TROUGH /A FOCUS!/ TAPS THE LAST OF THE MOIST AND
UNSTABLE AIR. THEN ATTENTION TURNS TO HOW QUICKLY TEMPERATURES WILL
WARM AFTER THE SEASONAL AIR ON THU AND FRI.
THIS MORNING...WELL-DEFINED UPPER TROUGH ACROSS WESTERN ONTARIO TO
NORTHERN IA IS PROGRESSING ESE. THE SURFACE TROUGH EXTENDS FROM A
1000MB LOW IN EASTERN ONTARIO TO THE QUAD CITIES AT 3 AM THIS
MORNING. DEW POINTS IN THE MID 70S ARE POOLED ACROSS THE AREA
OFFERING A MUGGY START TO THE DAY. SCATTERED ACCAS IS SEEN ON IR IN
THE REGION BUT NO SIGNS ON RADAR OR SATELLITE OF THIS DEVELOPING. A
SHORT WAVE IMPULSE SEEN ON WATER VAPOR AND 700MB PROFILER ANALYSIS
IS TRAVERSING SOUTHERN IA/NORTHERN MO...BASICALLY ALONG THE BASE
OF THE PRIMARY TROUGH. WHILE CONVECTIVE ALLOWING GUIDANCE SUCH AS
THE HRRR DOES HAVE CONVECTIVE DEVELOPMENT TRAVERSING THE FAR
SOUTHERN FORECAST AREA WITH THIS AND ALONG THE SURFACE BOUNDARY
DURING MID-MORNING...RADAR TRENDS SHOW SUBTLE ECHOES FURTHER SOUTH.
THE LOW-LEVEL JET HAS VEERED AND THE MORE SUBSTANTIAL MOISTURE
TRANSPORT HAS ALSO ENDED EARLY THIS MORNING...SO NOT SEEING TOO MUCH
HAPPENING. SO ONLY MAINTAINED LOW T-STORM CHANCES IN THE SOUTHERN
FORECAST AREA.
THIS AFTERNOON INTO TONIGHT...SUBSTANTIAL COLUMN DRYING IS FORECAST
AS THE AFTERNOON PROGRESSES. SURFACE DEW POINTS WILL FALL SLOWLY
THROUGH THE 60S AND WILL LIKELY STILL SUPPORT AT LEAST FEW AND
POTENTIALLY SCATTERED CU. THE 850MB TEMPERATURES IN THE MID-UPPER
TEENS FORECAST AT 18Z ACROSS THE FORECAST AREA...ALONG WITH THE WARM
STARTING POINT FOR TEMPERATURES...INDICATE MANY COMMUNITIES
REACHING THE MID AND POTENTIALLY UPPER 80S. AREAS NEAR THE WI STATE
LINE ARE MORE LIKELY TO FLAT-LINE IN TEMPERATURES THIS AFTERNOON AS
THE COOL FRONT PORTION OF THIS TROUGH WORKS THROUGH. NORTHWEST WINDS
IN THE BOUNDARY LAYER WILL BE RIGHT AT THE CUSP AT KEEPING A LAKE
BREEZE AT BAY FOR CHICAGO BUT SOME COOLING OF SEVERAL DEGREES COULD
BE SEEN BY MID-AFTERNOON IMMEDIATELY NEAR THE IL LAKESHORE AND
DEFINITELY NEAR THE IN SHORE.
THURSDAY THROUGH FRIDAY...A QUIET TIME AS SURFACE HIGH PRESSURE ON
THE ORDER OF 1019 MB MOVES ATOP THE AREA. THERE SHOULD BE LIMITED
CIRRUS AND ONLY FEW CU DURING THE AFTERNOONS. A MODEL BLEND
TYPICALLY DOES VERY WELL FOR TEMPS IN THIS TYPE OF CALM REGIME AND
HAVE BLENDED THAT WITH GOING FORECAST. TEMPERATURES SHOULD BE
WITHIN A COUPLE DEGREES OF OR RIGHT AT NORMAL.
THIS WEEKEND INTO EARLY NEXT WEEK...THE TREND IN LONG RANGE GUIDANCE
CONTINUES TO POINT TOWARD A WARMER AND DRIER TIME THAN SOLUTIONS
FROM A COUPLE DAYS AGO WITH STOUT UPPER RIDGING FROM THE WEST
SOUTHWEST STRETCHING OVER THE AREA. THE ADVANCING RIDGE FROM THE
WEST LATE THIS WEEK GETS HELD UP WITH BOTH A CLOSED LOW IN THE
NORTHEAST/MID-ATLANTIC AND TROPICAL STORM CHANTAL...FORECAST BY NHC
TO BE NEAR THE GA/SC SHORE BY LATE SUNDAY. 500MB HEIGHTS IN EXCESS
OF 594DM ARE FORECAST BY BOTH THE EC AN GFS FOR THE WEEKEND. WHILE
THE EC WEAKENS THIS MORE THAN THE GFS EARLY NEXT WEEK...THE PATTERN
FORECAST IS STILL BLOCKED AND RIDGE RIDING ACTIVITY IS FORECAST FOR
MOST OF THIS TIME FAIRLY FAR NORTH. BUT AS WE SAW IN THE JUNE 22-26
STRETCH...THAT CAN EVOLVE FURTHER SOUTH THAN LONG RANGE SOLUTIONS
SHOW AS MULTIPLE ROUNDS OF CONVECTION FIRE. BUT THIS IS CERTAINLY A
STRONGER RIDGE FORECAST THIS FAR NORTHEAST. THE 850MB 20C TEMP
CONTOUR FLIRTS WITH THE CWA ON BOTH SOLUTIONS FROM SAT THROUGH TUE.
HAVE BOOSTED TEMPS A COUPLE DEGREES FURTHER AND IF THAT THERMAL
RIDGE ENDS UP FURTHER SOUTH UNCONTAMINATED WITH CONVECTIVE
CLOUDS...CAN CERTAINLY ENVISION AT LEAST LOW 90S AWAY FROM THE LAKE
FOR MULTIPLE DAYS. BUT CONFIDENCE ENVELOPE...WHILE NOT OVERLY
LARGE...IS CENTERED MORE ON UPPER 80S /LOW-MID NEAR THE LAKE/. THE
EASTERN ATLANTIC/GULF FLOW LOOKS TO RETURN HIGHER DEW POINTS BY SUN
OR MON.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* VARIABLE WINDS BETWEEN APPROX 300 AND 350 THROUGH EARLY AFTERNOON
WITH SPORADIC GUSTS TO THE MID TEENS.
* STEADIER NORTHEAST WIND EXPECTED WITH LAKE PUSH IN THE NEXT 1 TO
2 HOURS.
MDB/KJB
//DISCUSSION...UPDATED 18Z...
THE WEATHER PATTERN IS QUIETING DOWN ACROSS THE REGION AS A COLD
FRONT CONTINUES TO SHIFT SOUTH ACROSS ILLINOIS AND INDIANA EARLY
THIS AFTERNOON. ASIDE FROM SOME SCT TO OCCASIONALLY BKN CIGS AROUND
4000 FEET...SKIES SHOULD REMAIN FAIRLY CLEAR...ESPECIALLY TONIGHT.
THE WINDS WILL BE THE MAIN ISSUE THIS AFTERNOON. LOCAL RADAR
DATA...ALONG WITH AREA SURFACE OBSERVATIONS INDICATE THAT THE LAKE
BREEZE BOUNDARY REMAINS DRAPED FROM NORTH TO SOUTH ACROSS EASTERN
COOK COUNTY ABOUT 5 TO 10 MILES EAST OF THE TERMINALS. THE BOUNDARY
DOES APPEAR TO BE MOVING SLOWLY WESTWARD...AND IT STILL APPEARS THAT
A WIND SHIFT MAY OCCUR AT THE TERMINALS OVER THE NEXT 1 TO 2 HOURS.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM CONFIDENCE IN A STEADIER NORTHEAST WIND DEVELOPING AFTER
19 UTC.
KJB
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR.
FRIDAY...VFR.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...VFR.
TUESDAY...VFR.
RODRIGUEZ
&&
.MARINE...
416 AM CDT
AS A TROUGH OF LOW PRESSURE AND ASSOCIATED COLD FRONT BEGIN TO
PUSH EAST ACROSS THE NORTHERN PORTIONS OF THE LAKE THIS
MORNING...A FAIRLY TIGHT PRESSURE GRADIENT HAS HELPED SOUTHWEST
WINDS TO INCREASE TO 15 TO 25 KT OVER THE NORTHERN PORTIONS OF THE
LAKE WHILE AREAS FURTHER SOUTH ARE OBSERVING SPEEDS OF 10 TO 20
KT. AS THIS TROUGH/FRONT CONTINUE SOUTHEAST DOWN THE LAKE THIS
MORNING...EXPECT THESE SOUTHWEST WINDS TO SHIFT TO THE
WEST/NORTHWEST AND THEN HOLD ONTO A NORTHWEST DIRECTION FOR THE
REMAINDER OF THE DAY INTO TONIGHT. EXPECT LIGHT NORTHERLY FLOW
OVER THE LAKE FOR MOST OF THURSDAY AS HIGH PRESSURE SLOWLY SHIFTS
EAST TOWARDS THE CENTRAL GREAT LAKES. BY FRIDAY WINDS TURN BACK TO
A SOUTHERLY DIRECTION...AS THIS HIGH SETTLES OVER THE EASTERN
GREAT LAKES INTO THE WEEKEND.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1124 AM CDT WED JUL 10 2013
.DISCUSSION...
305 AM CDT
FORECAST CHALLENGES THIS WEDNESDAY MORNING INCLUDE STILL AWAITING
THE ARRIVAL OF CONVECTION. JOKING ASIDE...IT IS IMPRESSIVE TO GET
THROUGH THIS VERY HIGH PWAT AND UNSTABLE AIR ALOFT /MUCAPES
2000-3500 J/KG/ WITHOUT CONVECTION FROM MIDDAY YESTERDAY THROUGH
LAST NIGHT. IT REMINDED HOW IMPORTANT THE TIMING OF A TRIGGER OR
SOME FORM OF FOCI ARE FOR CONVECTION...OR INHIBITING DEVELOPMENT IF
IN THE WAKE OF SUCH FEATURES. BUT BACK TO THE CHALLENGES GOING
FORWARD...THERE IS A CHANCE FOR CONVECTION THIS MORNING SOUTH OF
I-80 AS THE SURFACE TROUGH /A FOCUS!/ TAPS THE LAST OF THE MOIST AND
UNSTABLE AIR. THEN ATTENTION TURNS TO HOW QUICKLY TEMPERATURES WILL
WARM AFTER THE SEASONAL AIR ON THU AND FRI.
THIS MORNING...WELL-DEFINED UPPER TROUGH ACROSS WESTERN ONTARIO TO
NORTHERN IA IS PROGRESSING ESE. THE SURFACE TROUGH EXTENDS FROM A
1000MB LOW IN EASTERN ONTARIO TO THE QUAD CITIES AT 3 AM THIS
MORNING. DEW POINTS IN THE MID 70S ARE POOLED ACROSS THE AREA
OFFERING A MUGGY START TO THE DAY. SCATTERED ACCAS IS SEEN ON IR IN
THE REGION BUT NO SIGNS ON RADAR OR SATELLITE OF THIS DEVELOPING. A
SHORT WAVE IMPULSE SEEN ON WATER VAPOR AND 700MB PROFILER ANALYSIS
IS TRAVERSING SOUTHERN IA/NORTHERN MO...BASICALLY ALONG THE BASE
OF THE PRIMARY TROUGH. WHILE CONVECTIVE ALLOWING GUIDANCE SUCH AS
THE HRRR DOES HAVE CONVECTIVE DEVELOPMENT TRAVERSING THE FAR
SOUTHERN FORECAST AREA WITH THIS AND ALONG THE SURFACE BOUNDARY
DURING MID-MORNING...RADAR TRENDS SHOW SUBTLE ECHOES FURTHER SOUTH.
THE LOW-LEVEL JET HAS VEERED AND THE MORE SUBSTANTIAL MOISTURE
TRANSPORT HAS ALSO ENDED EARLY THIS MORNING...SO NOT SEEING TOO MUCH
HAPPENING. SO ONLY MAINTAINED LOW T-STORM CHANCES IN THE SOUTHERN
FORECAST AREA.
THIS AFTERNOON INTO TONIGHT...SUBSTANTIAL COLUMN DRYING IS FORECAST
AS THE AFTERNOON PROGRESSES. SURFACE DEW POINTS WILL FALL SLOWLY
THROUGH THE 60S AND WILL LIKELY STILL SUPPORT AT LEAST FEW AND
POTENTIALLY SCATTERED CU. THE 850MB TEMPERATURES IN THE MID-UPPER
TEENS FORECAST AT 18Z ACROSS THE FORECAST AREA...ALONG WITH THE WARM
STARTING POINT FOR TEMPERATURES...INDICATE MANY COMMUNITIES
REACHING THE MID AND POTENTIALLY UPPER 80S. AREAS NEAR THE WI STATE
LINE ARE MORE LIKELY TO FLAT-LINE IN TEMPERATURES THIS AFTERNOON AS
THE COOL FRONT PORTION OF THIS TROUGH WORKS THROUGH. NORTHWEST WINDS
IN THE BOUNDARY LAYER WILL BE RIGHT AT THE CUSP AT KEEPING A LAKE
BREEZE AT BAY FOR CHICAGO BUT SOME COOLING OF SEVERAL DEGREES COULD
BE SEEN BY MID-AFTERNOON IMMEDIATELY NEAR THE IL LAKESHORE AND
DEFINITELY NEAR THE IN SHORE.
THURSDAY THROUGH FRIDAY...A QUIET TIME AS SURFACE HIGH PRESSURE ON
THE ORDER OF 1019 MB MOVES ATOP THE AREA. THERE SHOULD BE LIMITED
CIRRUS AND ONLY FEW CU DURING THE AFTERNOONS. A MODEL BLEND
TYPICALLY DOES VERY WELL FOR TEMPS IN THIS TYPE OF CALM REGIME AND
HAVE BLENDED THAT WITH GOING FORECAST. TEMPERATURES SHOULD BE
WITHIN A COUPLE DEGREES OF OR RIGHT AT NORMAL.
THIS WEEKEND INTO EARLY NEXT WEEK...THE TREND IN LONG RANGE GUIDANCE
CONTINUES TO POINT TOWARD A WARMER AND DRIER TIME THAN SOLUTIONS
FROM A COUPLE DAYS AGO WITH STOUT UPPER RIDGING FROM THE WEST
SOUTHWEST STRETCHING OVER THE AREA. THE ADVANCING RIDGE FROM THE
WEST LATE THIS WEEK GETS HELD UP WITH BOTH A CLOSED LOW IN THE
NORTHEAST/MID-ATLANTIC AND TROPICAL STORM CHANTAL...FORECAST BY NHC
TO BE NEAR THE GA/SC SHORE BY LATE SUNDAY. 500MB HEIGHTS IN EXCESS
OF 594DM ARE FORECAST BY BOTH THE EC AN GFS FOR THE WEEKEND. WHILE
THE EC WEAKENS THIS MORE THAN THE GFS EARLY NEXT WEEK...THE PATTERN
FORECAST IS STILL BLOCKED AND RIDGE RIDING ACTIVITY IS FORECAST FOR
MOST OF THIS TIME FAIRLY FAR NORTH. BUT AS WE SAW IN THE JUNE 22-26
STRETCH...THAT CAN EVOLVE FURTHER SOUTH THAN LONG RANGE SOLUTIONS
SHOW AS MULTIPLE ROUNDS OF CONVECTION FIRE. BUT THIS IS CERTAINLY A
STRONGER RIDGE FORECAST THIS FAR NORTHEAST. THE 850MB 20C TEMP
CONTOUR FLIRTS WITH THE CWA ON BOTH SOLUTIONS FROM SAT THROUGH TUE.
HAVE BOOSTED TEMPS A COUPLE DEGREES FURTHER AND IF THAT THERMAL
RIDGE ENDS UP FURTHER SOUTH UNCONTAMINATED WITH CONVECTIVE
CLOUDS...CAN CERTAINLY ENVISION AT LEAST LOW 90S AWAY FROM THE LAKE
FOR MULTIPLE DAYS. BUT CONFIDENCE ENVELOPE...WHILE NOT OVERLY
LARGE...IS CENTERED MORE ON UPPER 80S /LOW-MID NEAR THE LAKE/. THE
EASTERN ATLANTIC/GULF FLOW LOOKS TO RETURN HIGHER DEW POINTS BY SUN
OR MON.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* VARIABLE WINDS BETWEEN APPROX 350 AND 020 THROUGH EARLY
AFTERNOON WITH SPORADIC GUSTS TO THE MID TEENS.
* STEADIER NORTHEAST WIND EXPECTED WITH LAKE PUSH MID AFTERNOON.
MDB
//DISCUSSION...UPDATED 16Z.
WINDS REMAIN THE MAIN ISSUE THROUGH THE AFTERNOON...MAINLY ACROSS
THE CHICAGO AND NW INDIANA AREA. PRESSURE GRADIENT HAS ALIGNED AS
TO ALLOW A MORE NORTHERLY DIRECTION TO SET UP CLOSE TO THE LAKE
WITH A LAKE BREEZE ALSO DEVELOPING AND SLOWLY PUSHING INLAND. THIS
SHOULD SUPPORT SOME VARIABILITY IN WIND DIRECTION AT ORD/MDW OVER
THE NEXT FEW HOURS BETWEEN ROUGHLY 350 AND 020. THIS WILL LIKELY
CONTINUE UNTIL THE LAKE BREEZE CAN WORK ITS WAY INLAND TURNING
WINDS NORTHEAST WHICH IS EXPECTED TO OCCUR MID AFTERNOON. IT IS
POSSIBLE THAT CONVERGENCE COULD SET UP JUST EAST OF THE TERMINALS
ALLOWING THEM TO TURN MORE NNW BUT THIS APPEARS TO BE ESTABLISHING
ITSELF WEST OF THE TERMINALS AT THIS TIME.
MDB
FROM 12Z...
AS THE FRONTAL BOUNDARY IS CURRENTLY SOUTH OF THE TERMINALS THIS
MORNING...THE SHOWER/TS DEVELOPMENT ACROSS CENTRAL ILLINOIS WILL
REMAIN SOUTH OF THE TERMINALS TODAY. ALTHOUGH WITH FROPA AND A
WEAK GRADIENT IN PLACE...SOME SCATTERED LOWER CEILINGS AND FOG
REMAIN NEAR THE TERMINALS. WITH THE SUN QUICKLY RISING THIS
MORNING...ANY LINGERING FOG/CEILINGS SHOULD QUICKLY DIMINISH WITH
LATEST SATELLITE IMAGERY ALREADY SHOWING THIS OCCURRING. ALTHOUGH
IT WOULD NOT BE OUT OF THE QUESTION FOR A BRIEF PERIOD OF LOWER
CEILINGS AROUND 2KFT OVER THE NEXT HOUR...MAINLY FOR MDW/GYY. ANY
FURTHER CLOUD DEVELOPMENT TODAY SHOULD REMAIN SCATTERED AS DRIER
AIR CONTINUES TO PUSH SOUTH ON INCREASING NORTHWEST WINDS THIS
MORNING. RFD AND DPA SHOULD REMAIN NORTHWEST WITH GUSTS INCREASING
BY MID MORNING...WITH ORD/MDW/GYY LIKEWISE OBSERVING THIS TREND
BUT ONLY THROUGH THE MORNING. EXPECT A TREND TOWARDS A NORTHEAST
DIRECTION BY EARLY AFTERNOON FOR ORD/MDW/GYY...REMAINING THIS
DIRECTION UNTIL LATER THIS EVENING.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM CONFIDENCE IN VARIABLE 350-020 WINDS.
* MEDIUM CONFIDENCE IN A STEADIER NORTHEAST WIND DEVELOPING MID
AFTERNOON...MEDIUM CONFIDENCE IN TIMING.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR.
FRIDAY...VFR.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...VFR.
TUESDAY...VFR.
RODRIGUEZ
&&
.MARINE...
416 AM CDT
AS A TROUGH OF LOW PRESSURE AND ASSOCIATED COLD FRONT BEGIN TO
PUSH EAST ACROSS THE NORTHERN PORTIONS OF THE LAKE THIS
MORNING...A FAIRLY TIGHT PRESSURE GRADIENT HAS HELPED SOUTHWEST
WINDS TO INCREASE TO 15 TO 25 KT OVER THE NORTHERN PORTIONS OF THE
LAKE WHILE AREAS FURTHER SOUTH ARE OBSERVING SPEEDS OF 10 TO 20
KT. AS THIS TROUGH/FRONT CONTINUE SOUTHEAST DOWN THE LAKE THIS
MORNING...EXPECT THESE SOUTHWEST WINDS TO SHIFT TO THE
WEST/NORTHWEST AND THEN HOLD ONTO A NORTHWEST DIRECTION FOR THE
REMAINDER OF THE DAY INTO TONIGHT. EXPECT LIGHT NORTHERLY FLOW
OVER THE LAKE FOR MOST OF THURSDAY AS HIGH PRESSURE SLOWLY SHIFTS
EAST TOWARDS THE CENTRAL GREAT LAKES. BY FRIDAY WINDS TURN BACK TO
A SOUTHERLY DIRECTION...AS THIS HIGH SETTLES OVER THE EASTERN
GREAT LAKES INTO THE WEEKEND.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
906 AM CDT WED JUL 10 2013
.DISCUSSION...
305 AM CDT
FORECAST CHALLENGES THIS WEDNESDAY MORNING INCLUDE STILL AWAITING
THE ARRIVAL OF CONVECTION. JOKING ASIDE...IT IS IMPRESSIVE TO GET
THROUGH THIS VERY HIGH PWAT AND UNSTABLE AIR ALOFT /MUCAPES
2000-3500 J/KG/ WITHOUT CONVECTION FROM MIDDAY YESTERDAY THROUGH
LAST NIGHT. IT REMINDED HOW IMPORTANT THE TIMING OF A TRIGGER OR
SOME FORM OF FOCI ARE FOR CONVECTION...OR INHIBITING DEVELOPMENT IF
IN THE WAKE OF SUCH FEATURES. BUT BACK TO THE CHALLENGES GOING
FORWARD...THERE IS A CHANCE FOR CONVECTION THIS MORNING SOUTH OF
I-80 AS THE SURFACE TROUGH /A FOCUS!/ TAPS THE LAST OF THE MOIST AND
UNSTABLE AIR. THEN ATTENTION TURNS TO HOW QUICKLY TEMPERATURES WILL
WARM AFTER THE SEASONAL AIR ON THU AND FRI.
THIS MORNING...WELL-DEFINED UPPER TROUGH ACROSS WESTERN ONTARIO TO
NORTHERN IA IS PROGRESSING ESE. THE SURFACE TROUGH EXTENDS FROM A
1000MB LOW IN EASTERN ONTARIO TO THE QUAD CITIES AT 3 AM THIS
MORNING. DEW POINTS IN THE MID 70S ARE POOLED ACROSS THE AREA
OFFERING A MUGGY START TO THE DAY. SCATTERED ACCAS IS SEEN ON IR IN
THE REGION BUT NO SIGNS ON RADAR OR SATELLITE OF THIS DEVELOPING. A
SHORT WAVE IMPULSE SEEN ON WATER VAPOR AND 700MB PROFILER ANALYSIS
IS TRAVERSING SOUTHERN IA/NORTHERN MO...BASICALLY ALONG THE BASE
OF THE PRIMARY TROUGH. WHILE CONVECTIVE ALLOWING GUIDANCE SUCH AS
THE HRRR DOES HAVE CONVECTIVE DEVELOPMENT TRAVERSING THE FAR
SOUTHERN FORECAST AREA WITH THIS AND ALONG THE SURFACE BOUNDARY
DURING MID-MORNING...RADAR TRENDS SHOW SUBTLE ECHOES FURTHER SOUTH.
THE LOW-LEVEL JET HAS VEERED AND THE MORE SUBSTANTIAL MOISTURE
TRANSPORT HAS ALSO ENDED EARLY THIS MORNING...SO NOT SEEING TOO MUCH
HAPPENING. SO ONLY MAINTAINED LOW T-STORM CHANCES IN THE SOUTHERN
FORECAST AREA.
THIS AFTERNOON INTO TONIGHT...SUBSTANTIAL COLUMN DRYING IS FORECAST
AS THE AFTERNOON PROGRESSES. SURFACE DEW POINTS WILL FALL SLOWLY
THROUGH THE 60S AND WILL LIKELY STILL SUPPORT AT LEAST FEW AND
POTENTIALLY SCATTERED CU. THE 850MB TEMPERATURES IN THE MID-UPPER
TEENS FORECAST AT 18Z ACROSS THE FORECAST AREA...ALONG WITH THE WARM
STARTING POINT FOR TEMPERATURES...INDICATE MANY COMMUNITIES
REACHING THE MID AND POTENTIALLY UPPER 80S. AREAS NEAR THE WI STATE
LINE ARE MORE LIKELY TO FLAT-LINE IN TEMPERATURES THIS AFTERNOON AS
THE COOL FRONT PORTION OF THIS TROUGH WORKS THROUGH. NORTHWEST WINDS
IN THE BOUNDARY LAYER WILL BE RIGHT AT THE CUSP AT KEEPING A LAKE
BREEZE AT BAY FOR CHICAGO BUT SOME COOLING OF SEVERAL DEGREES COULD
BE SEEN BY MID-AFTERNOON IMMEDIATELY NEAR THE IL LAKESHORE AND
DEFINITELY NEAR THE IN SHORE.
THURSDAY THROUGH FRIDAY...A QUIET TIME AS SURFACE HIGH PRESSURE ON
THE ORDER OF 1019 MB MOVES ATOP THE AREA. THERE SHOULD BE LIMITED
CIRRUS AND ONLY FEW CU DURING THE AFTERNOONS. A MODEL BLEND
TYPICALLY DOES VERY WELL FOR TEMPS IN THIS TYPE OF CALM REGIME AND
HAVE BLENDED THAT WITH GOING FORECAST. TEMPERATURES SHOULD BE
WITHIN A COUPLE DEGREES OF OR RIGHT AT NORMAL.
THIS WEEKEND INTO EARLY NEXT WEEK...THE TREND IN LONG RANGE GUIDANCE
CONTINUES TO POINT TOWARD A WARMER AND DRIER TIME THAN SOLUTIONS
FROM A COUPLE DAYS AGO WITH STOUT UPPER RIDGING FROM THE WEST
SOUTHWEST STRETCHING OVER THE AREA. THE ADVANCING RIDGE FROM THE
WEST LATE THIS WEEK GETS HELD UP WITH BOTH A CLOSED LOW IN THE
NORTHEAST/MID-ATLANTIC AND TROPICAL STORM CHANTAL...FORECAST BY NHC
TO BE NEAR THE GA/SC SHORE BY LATE SUNDAY. 500MB HEIGHTS IN EXCESS
OF 594DM ARE FORECAST BY BOTH THE EC AN GFS FOR THE WEEKEND. WHILE
THE EC WEAKENS THIS MORE THAN THE GFS EARLY NEXT WEEK...THE PATTERN
FORECAST IS STILL BLOCKED AND RIDGE RIDING ACTIVITY IS FORECAST FOR
MOST OF THIS TIME FAIRLY FAR NORTH. BUT AS WE SAW IN THE JUNE 22-26
STRETCH...THAT CAN EVOLVE FURTHER SOUTH THAN LONG RANGE SOLUTIONS
SHOW AS MULTIPLE ROUNDS OF CONVECTION FIRE. BUT THIS IS CERTAINLY A
STRONGER RIDGE FORECAST THIS FAR NORTHEAST. THE 850MB 20C TEMP
CONTOUR FLIRTS WITH THE CWA ON BOTH SOLUTIONS FROM SAT THROUGH TUE.
HAVE BOOSTED TEMPS A COUPLE DEGREES FURTHER AND IF THAT THERMAL
RIDGE ENDS UP FURTHER SOUTH UNCONTAMINATED WITH CONVECTIVE
CLOUDS...CAN CERTAINLY ENVISION AT LEAST LOW 90S AWAY FROM THE LAKE
FOR MULTIPLE DAYS. BUT CONFIDENCE ENVELOPE...WHILE NOT OVERLY
LARGE...IS CENTERED MORE ON UPPER 80S /LOW-MID NEAR THE LAKE/. THE
EASTERN ATLANTIC/GULF FLOW LOOKS TO RETURN HIGHER DEW POINTS BY SUN
OR MON.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* NORTHWEST WINDS INCREASING THROUGH MID MORNING WITH GUSTS IN THE
UPPER TEENS...BEFORE WINDS SHIFT TO THE NORTHEAST IN THE
AFTERNOON WITH LAKE INFLUENCE.
MDB
//DISCUSSION...UPDATED 12Z...
AS THE FRONTAL BOUNDARY IS CURRENTLY SOUTH OF THE TERMINALS THIS
MORNING...THE SHOWER/TS DEVELOPMENT ACROSS CENTRAL ILLINOIS WILL
REMAIN SOUTH OF THE TERMINALS TODAY. ALTHOUGH WITH FROPA AND A
WEAK GRADIENT IN PLACE...SOME SCATTERED LOWER CEILINGS AND FOG
REMAIN NEAR THE TERMINALS. WITH THE SUN QUICKLY RISING THIS
MORNING...ANY LINGERING FOG/CEILINGS SHOULD QUICKLY DIMINISH WITH
LATEST SATELLITE IMAGERY ALREADY SHOWING THIS OCCURRING. ALTHOUGH
IT WOULD NOT BE OUT OF THE QUESTION FOR A BRIEF PERIOD OF LOWER
CEILINGS AROUND 2KFT OVER THE NEXT HOUR...MAINLY FOR MDW/GYY. ANY
FURTHER CLOUD DEVELOPMENT TODAY SHOULD REMAIN SCATTERED AS DRIER
AIR CONTINUES TO PUSH SOUTH ON INCREASING NORTHWEST WINDS THIS
MORNING. RFD AND DPA SHOULD REMAIN NORTHWEST WITH GUSTS INCREASING
BY MID MORNING...WITH ORD/MDW/GYY LIKEWISE OBSERVING THIS TREND
BUT ONLY THROUGH THE MORNING. EXPECT A TREND TOWARDS A NORTHEAST
DIRECTION BY EARLY AFTERNOON FOR ORD/MDW/GYY...REMAINING THIS
DIRECTION UNTIL LATER THIS EVENING.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* HIGH CONFIDENCE IN WIND FORECAST THROUGH EARLY
AFTERNOON...MEDIUM CONFIDENCE THAT A SHIFT TO NORTHEAST WILL
OCCUR THIS AFTERNOON...MEDIUM CONFIDENCE IN TIMING OF SHIFT.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR.
FRIDAY...VFR.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...VFR.
TUESDAY...VFR.
RODRIGUEZ
&&
.MARINE...
416 AM CDT
AS A TROUGH OF LOW PRESSURE AND ASSOCIATED COLD FRONT BEGIN TO
PUSH EAST ACROSS THE NORTHERN PORTIONS OF THE LAKE THIS
MORNING...A FAIRLY TIGHT PRESSURE GRADIENT HAS HELPED SOUTHWEST
WINDS TO INCREASE TO 15 TO 25 KT OVER THE NORTHERN PORTIONS OF THE
LAKE WHILE AREAS FURTHER SOUTH ARE OBSERVING SPEEDS OF 10 TO 20
KT. AS THIS TROUGH/FRONT CONTINUE SOUTHEAST DOWN THE LAKE THIS
MORNING...EXPECT THESE SOUTHWEST WINDS TO SHIFT TO THE
WEST/NORTHWEST AND THEN HOLD ONTO A NORTHWEST DIRECTION FOR THE
REMAINDER OF THE DAY INTO TONIGHT. EXPECT LIGHT NORTHERLY FLOW
OVER THE LAKE FOR MOST OF THURSDAY AS HIGH PRESSURE SLOWLY SHIFTS
EAST TOWARDS THE CENTRAL GREAT LAKES. BY FRIDAY WINDS TURN BACK TO
A SOUTHERLY DIRECTION...AS THIS HIGH SETTLES OVER THE EASTERN
GREAT LAKES INTO THE WEEKEND.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
654 AM CDT WED JUL 10 2013
.DISCUSSION...
305 AM CDT
FORECAST CHALLENGES THIS WEDNESDAY MORNING INCLUDE STILL AWAITING
THE ARRIVAL OF CONVECTION. JOKING ASIDE...IT IS IMPRESSIVE TO GET
THROUGH THIS VERY HIGH PWAT AND UNSTABLE AIR ALOFT /MUCAPES
2000-3500 J/KG/ WITHOUT CONVECTION FROM MIDDAY YESTERDAY THROUGH
LAST NIGHT. IT REMINDED HOW IMPORTANT THE TIMING OF A TRIGGER OR
SOME FORM OF FOCI ARE FOR CONVECTION...OR INHIBITING DEVELOPMENT IF
IN THE WAKE OF SUCH FEATURES. BUT BACK TO THE CHALLENGES GOING
FORWARD...THERE IS A CHANCE FOR CONVECTION THIS MORNING SOUTH OF
I-80 AS THE SURFACE TROUGH /A FOCUS!/ TAPS THE LAST OF THE MOIST AND
UNSTABLE AIR. THEN ATTENTION TURNS TO HOW QUICKLY TEMPERATURES WILL
WARM AFTER THE SEASONAL AIR ON THU AND FRI.
THIS MORNING...WELL-DEFINED UPPER TROUGH ACROSS WESTERN ONTARIO TO
NORTHERN IA IS PROGRESSING ESE. THE SURFACE TROUGH EXTENDS FROM A
1000MB LOW IN EASTERN ONTARIO TO THE QUAD CITIES AT 3 AM THIS
MORNING. DEW POINTS IN THE MID 70S ARE POOLED ACROSS THE AREA
OFFERING A MUGGY START TO THE DAY. SCATTERED ACCAS IS SEEN ON IR IN
THE REGION BUT NO SIGNS ON RADAR OR SATELLITE OF THIS DEVELOPING. A
SHORT WAVE IMPULSE SEEN ON WATER VAPOR AND 700MB PROFILER ANALYSIS
IS TRAVERSING SOUTHERN IA/NORTHERN MO...BASICALLY ALONG THE BASE
OF THE PRIMARY TROUGH. WHILE CONVECTIVE ALLOWING GUIDANCE SUCH AS
THE HRRR DOES HAVE CONVECTIVE DEVELOPMENT TRAVERSING THE FAR
SOUTHERN FORECAST AREA WITH THIS AND ALONG THE SURFACE BOUNDARY
DURING MID-MORNING...RADAR TRENDS SHOW SUBTLE ECHOES FURTHER SOUTH.
THE LOW-LEVEL JET HAS VEERED AND THE MORE SUBSTANTIAL MOISTURE
TRANSPORT HAS ALSO ENDED EARLY THIS MORNING...SO NOT SEEING TOO MUCH
HAPPENING. SO ONLY MAINTAINED LOW T-STORM CHANCES IN THE SOUTHERN
FORECAST AREA.
THIS AFTERNOON INTO TONIGHT...SUBSTANTIAL COLUMN DRYING IS FORECAST
AS THE AFTERNOON PROGRESSES. SURFACE DEW POINTS WILL FALL SLOWLY
THROUGH THE 60S AND WILL LIKELY STILL SUPPORT AT LEAST FEW AND
POTENTIALLY SCATTERED CU. THE 850MB TEMPERATURES IN THE MID-UPPER
TEENS FORECAST AT 18Z ACROSS THE FORECAST AREA...ALONG WITH THE WARM
STARTING POINT FOR TEMPERATURES...INDICATE MANY COMMUNITIES
REACHING THE MID AND POTENTIALLY UPPER 80S. AREAS NEAR THE WI STATE
LINE ARE MORE LIKELY TO FLAT-LINE IN TEMPERATURES THIS AFTERNOON AS
THE COOL FRONT PORTION OF THIS TROUGH WORKS THROUGH. NORTHWEST WINDS
IN THE BOUNDARY LAYER WILL BE RIGHT AT THE CUSP AT KEEPING A LAKE
BREEZE AT BAY FOR CHICAGO BUT SOME COOLING OF SEVERAL DEGREES COULD
BE SEEN BY MID-AFTERNOON IMMEDIATELY NEAR THE IL LAKESHORE AND
DEFINITELY NEAR THE IN SHORE.
THURSDAY THROUGH FRIDAY...A QUIET TIME AS SURFACE HIGH PRESSURE ON
THE ORDER OF 1019 MB MOVES ATOP THE AREA. THERE SHOULD BE LIMITED
CIRRUS AND ONLY FEW CU DURING THE AFTERNOONS. A MODEL BLEND
TYPICALLY DOES VERY WELL FOR TEMPS IN THIS TYPE OF CALM REGIME AND
HAVE BLENDED THAT WITH GOING FORECAST. TEMPERATURES SHOULD BE
WITHIN A COUPLE DEGREES OF OR RIGHT AT NORMAL.
THIS WEEKEND INTO EARLY NEXT WEEK...THE TREND IN LONG RANGE GUIDANCE
CONTINUES TO POINT TOWARD A WARMER AND DRIER TIME THAN SOLUTIONS
FROM A COUPLE DAYS AGO WITH STOUT UPPER RIDGING FROM THE WEST
SOUTHWEST STRETCHING OVER THE AREA. THE ADVANCING RIDGE FROM THE
WEST LATE THIS WEEK GETS HELD UP WITH BOTH A CLOSED LOW IN THE
NORTHEAST/MID-ATLANTIC AND TROPICAL STORM CHANTAL...FORECAST BY NHC
TO BE NEAR THE GA/SC SHORE BY LATE SUNDAY. 500MB HEIGHTS IN EXCESS
OF 594DM ARE FORECAST BY BOTH THE EC AN GFS FOR THE WEEKEND. WHILE
THE EC WEAKENS THIS MORE THAN THE GFS EARLY NEXT WEEK...THE PATTERN
FORECAST IS STILL BLOCKED AND RIDGE RIDING ACTIVITY IS FORECAST FOR
MOST OF THIS TIME FAIRLY FAR NORTH. BUT AS WE SAW IN THE JUNE 22-26
STRETCH...THAT CAN EVOLVE FURTHER SOUTH THAN LONG RANGE SOLUTIONS
SHOW AS MULTIPLE ROUNDS OF CONVECTION FIRE. BUT THIS IS CERTAINLY A
STRONGER RIDGE FORECAST THIS FAR NORTHEAST. THE 850MB 20C TEMP
CONTOUR FLIRTS WITH THE CWA ON BOTH SOLUTIONS FROM SAT THROUGH TUE.
HAVE BOOSTED TEMPS A COUPLE DEGREES FURTHER AND IF THAT THERMAL
RIDGE ENDS UP FURTHER SOUTH UNCONTAMINATED WITH CONVECTIVE
CLOUDS...CAN CERTAINLY ENVISION AT LEAST LOW 90S AWAY FROM THE LAKE
FOR MULTIPLE DAYS. BUT CONFIDENCE ENVELOPE...WHILE NOT OVERLY
LARGE...IS CENTERED MORE ON UPPER 80S /LOW-MID NEAR THE LAKE/. THE
EASTERN ATLANTIC/GULF FLOW LOOKS TO RETURN HIGHER DEW POINTS BY SUN
OR MON.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* LINGERING FOG AND SCATTERED LOW CEILINGS DIMINISHING EARLY THIS
MORNING.
* NORTHWEST WINDS INCREASING THROUGH MID MORNING WITH GUSTS IN THE
UPPER TEENS...BEFORE WINDS SHIFT TO THE NORTHEAST IN THE
AFTERNOON WITH LAKE INFLUENCE.
RODRIGUEZ
//DISCUSSION...UPDATED 12Z...
AS THE FRONTAL BOUNDARY IS CURRENTLY SOUTH OF THE TERMINALS THIS
MORNING...THE SHOWER/TS DEVELOPMENT ACROSS CENTRAL ILLINOIS WILL
REMAIN SOUTH OF THE TERMINALS TODAY. ALTHOUGH WITH FROPA AND A
WEAK GRADIENT IN PLACE...SOME SCATTERED LOWER CEILINGS AND FOG
REMAIN NEAR THE TERMINALS. WITH THE SUN QUICKLY RISING THIS
MORNING...ANY LINGERING FOG/CEILINGS SHOULD QUICKLY DIMINISH WITH
LATEST SATELLITE IMAGERY ALREADY SHOWING THIS OCCURRING. ALTHOUGH
IT WOULD NOT BE OUT OF THE QUESTION FOR A BRIEF PERIOD OF LOWER
CEILINGS AROUND 2KFT OVER THE NEXT HOUR...MAINLY FOR MDW/GYY. ANY
FURTHER CLOUD DEVELOPMENT TODAY SHOULD REMAIN SCATTERED AS DRIER
AIR CONTINUES TO PUSH SOUTH ON INCREASING NORTHWEST WINDS THIS
MORNING. RFD AND DPA SHOULD REMAIN NORTHWEST WITH GUSTS INCREASING
BY MID MORNING...WITH ORD/MDW/GYY LIKEWISE OBSERVING THIS TREND
BUT ONLY THROUGH THE MORNING. EXPECT A TREND TOWARDS A NORTHEAST
DIRECTION BY EARLY AFTERNOON FOR ORD/MDW/GYY...REMAINING THIS
DIRECTION UNTIL LATER THIS EVENING.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* MEDIUM HIGH CONFIDENCE WITH FOG/CEILING TRENDS.
* MEDIUM HIGH CONFIDENCE WITH WIND SPEED/DIRECTION.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR.
FRIDAY...VFR.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...VFR.
TUESDAY...VFR.
RODRIGUEZ
&&
.MARINE...
416 AM CDT
AS A TROUGH OF LOW PRESSURE AND ASSOCIATED COLD FRONT BEGIN TO
PUSH EAST ACROSS THE NORTHERN PORTIONS OF THE LAKE THIS
MORNING...A FAIRLY TIGHT PRESSURE GRADIENT HAS HELPED SOUTHWEST
WINDS TO INCREASE TO 15 TO 25 KT OVER THE NORTHERN PORTIONS OF THE
LAKE WHILE AREAS FURTHER SOUTH ARE OBSERVING SPEEDS OF 10 TO 20
KT. AS THIS TROUGH/FRONT CONTINUE SOUTHEAST DOWN THE LAKE THIS
MORNING...EXPECT THESE SOUTHWEST WINDS TO SHIFT TO THE
WEST/NORTHWEST AND THEN HOLD ONTO A NORTHWEST DIRECTION FOR THE
REMAINDER OF THE DAY INTO TONIGHT. EXPECT LIGHT NORTHERLY FLOW
OVER THE LAKE FOR MOST OF THURSDAY AS HIGH PRESSURE SLOWLY SHIFTS
EAST TOWARDS THE CENTRAL GREAT LAKES. BY FRIDAY WINDS TURN BACK TO
A SOUTHERLY DIRECTION...AS THIS HIGH SETTLES OVER THE EASTERN
GREAT LAKES INTO THE WEEKEND.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
424 AM CDT WED JUL 10 2013
.DISCUSSION...
305 AM CDT
FORECAST CHALLENGES THIS WEDNESDAY MORNING INCLUDE STILL AWAITING
THE ARRIVAL OF CONVECTION. JOKING ASIDE...IT IS IMPRESSIVE TO GET
THROUGH THIS VERY HIGH PWAT AND UNSTABLE AIR ALOFT /MUCAPES
2000-3500 J/KG/ WITHOUT CONVECTION FROM MIDDAY YESTERDAY THROUGH
LAST NIGHT. IT REMINDED HOW IMPORTANT THE TIMING OF A TRIGGER OR
SOME FORM OF FOCI ARE FOR CONVECTION...OR INHIBITING DEVELOPMENT IF
IN THE WAKE OF SUCH FEATURES. BUT BACK TO THE CHALLENGES GOING
FORWARD...THERE IS A CHANCE FOR CONVECTION THIS MORNING SOUTH OF
I-80 AS THE SURFACE TROUGH /A FOCUS!/ TAPS THE LAST OF THE MOIST AND
UNSTABLE AIR. THEN ATTENTION TURNS TO HOW QUICKLY TEMPERATURES WILL
WARM AFTER THE SEASONAL AIR ON THU AND FRI.
THIS MORNING...WELL-DEFINED UPPER TROUGH ACROSS WESTERN ONTARIO TO
NORTHERN IA IS PROGRESSING ESE. THE SURFACE TROUGH EXTENDS FROM A
1000MB LOW IN EASTERN ONTARIO TO THE QUAD CITIES AT 3 AM THIS
MORNING. DEW POINTS IN THE MID 70S ARE POOLED ACROSS THE AREA
OFFERING A MUGGY START TO THE DAY. SCATTERED ACCAS IS SEEN ON IR IN
THE REGION BUT NO SIGNS ON RADAR OR SATELLITE OF THIS DEVELOPING. A
SHORT WAVE IMPULSE SEEN ON WATER VAPOR AND 700MB PROFILER ANALYSIS
IS TRAVERSING SOUTHERN IA/NORTHERN MO...BASICALLY ALONG THE BASE
OF THE PRIMARY TROUGH. WHILE CONVECTIVE ALLOWING GUIDANCE SUCH AS
THE HRRR DOES HAVE CONVECTIVE DEVELOPMENT TRAVERSING THE FAR
SOUTHERN FORECAST AREA WITH THIS AND ALONG THE SURFACE BOUNDARY
DURING MID-MORNING...RADAR TRENDS SHOW SUBTLE ECHOES FURTHER SOUTH.
THE LOW-LEVEL JET HAS VEERED AND THE MORE SUBSTANTIAL MOISTURE
TRANSPORT HAS ALSO ENDED EARLY THIS MORNING...SO NOT SEEING TOO MUCH
HAPPENING. SO ONLY MAINTAINED LOW T-STORM CHANCES IN THE SOUTHERN
FORECAST AREA.
THIS AFTERNOON INTO TONIGHT...SUBSTANTIAL COLUMN DRYING IS FORECAST
AS THE AFTERNOON PROGRESSES. SURFACE DEW POINTS WILL FALL SLOWLY
THROUGH THE 60S AND WILL LIKELY STILL SUPPORT AT LEAST FEW AND
POTENTIALLY SCATTERED CU. THE 850MB TEMPERATURES IN THE MID-UPPER
TEENS FORECAST AT 18Z ACROSS THE FORECAST AREA...ALONG WITH THE WARM
STARTING POINT FOR TEMPERATURES...INDICATE MANY COMMUNITIES
REACHING THE MID AND POTENTIALLY UPPER 80S. AREAS NEAR THE WI STATE
LINE ARE MORE LIKELY TO FLAT-LINE IN TEMPERATURES THIS AFTERNOON AS
THE COOL FRONT PORTION OF THIS TROUGH WORKS THROUGH. NORTHWEST WINDS
IN THE BOUNDARY LAYER WILL BE RIGHT AT THE CUSP AT KEEPING A LAKE
BREEZE AT BAY FOR CHICAGO BUT SOME COOLING OF SEVERAL DEGREES COULD
BE SEEN BY MID-AFTERNOON IMMEDIATELY NEAR THE IL LAKESHORE AND
DEFINITELY NEAR THE IN SHORE.
THURSDAY THROUGH FRIDAY...A QUIET TIME AS SURFACE HIGH PRESSURE ON
THE ORDER OF 1019 MB MOVES ATOP THE AREA. THERE SHOULD BE LIMITED
CIRRUS AND ONLY FEW CU DURING THE AFTERNOONS. A MODEL BLEND
TYPICALLY DOES VERY WELL FOR TEMPS IN THIS TYPE OF CALM REGIME AND
HAVE BLENDED THAT WITH GOING FORECAST. TEMPERATURES SHOULD BE
WITHIN A COUPLE DEGREES OF OR RIGHT AT NORMAL.
THIS WEEKEND INTO EARLY NEXT WEEK...THE TREND IN LONG RANGE GUIDANCE
CONTINUES TO POINT TOWARD A WARMER AND DRIER TIME THAN SOLUTIONS
FROM A COUPLE DAYS AGO WITH STOUT UPPER RIDGING FROM THE WEST
SOUTHWEST STRETCHING OVER THE AREA. THE ADVANCING RIDGE FROM THE
WEST LATE THIS WEEK GETS HELD UP WITH BOTH A CLOSED LOW IN THE
NORTHEAST/MID-ATLANTIC AND TROPICAL STORM CHANTAL...FORECAST BY NHC
TO BE NEAR THE GA/SC SHORE BY LATE SUNDAY. 500MB HEIGHTS IN EXCESS
OF 594DM ARE FORECAST BY BOTH THE EC AN GFS FOR THE WEEKEND. WHILE
THE EC WEAKENS THIS MORE THAN THE GFS EARLY NEXT WEEK...THE PATTERN
FORECAST IS STILL BLOCKED AND RIDGE RIDING ACTIVITY IS FORECAST FOR
MOST OF THIS TIME FAIRLY FAR NORTH. BUT AS WE SAW IN THE JUNE 22-26
STRETCH...THAT CAN EVOLVE FURTHER SOUTH THAN LONG RANGE SOLUTIONS
SHOW AS MULTIPLE ROUNDS OF CONVECTION FIRE. BUT THIS IS CERTAINLY A
STRONGER RIDGE FORECAST THIS FAR NORTHEAST. THE 850MB 20C TEMP
CONTOUR FLIRTS WITH THE CWA ON BOTH SOLUTIONS FROM SAT THROUGH TUE.
HAVE BOOSTED TEMPS A COUPLE DEGREES FURTHER AND IF THAT THERMAL
RIDGE ENDS UP FURTHER SOUTH UNCONTAMINATED WITH CONVECTIVE
CLOUDS...CAN CERTAINLY ENVISION AT LEAST LOW 90S AWAY FROM THE LAKE
FOR MULTIPLE DAYS. BUT CONFIDENCE ENVELOPE...WHILE NOT OVERLY
LARGE...IS CENTERED MORE ON UPPER 80S /LOW-MID NEAR THE LAKE/. THE
EASTERN ATLANTIC/GULF FLOW LOOKS TO RETURN HIGHER DEW POINTS BY SUN
OR MON.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* BRIEF PERIOD OF VFR CEILINGS AND VIS EARLY THIS MORNING.
* ISOLATED SHRA ACROSS THE AREA EARLY THIS MORNING...BUT WITH A
LOW CHANCE FOR ANY PRECIP TO MOVE OVER THE TERMINALS.
* SOUTHWEST WINDS SHIFTING TO THE WEST/NORTHWEST WITH FROPA EARLY
THIS MORNING...WITH LAKE INFLUENCE TURNING THE WINDS NORTHEAST
IN THE AFTERNOON.
RODRIGUEZ
//DISCUSSION...UPDATED 06Z...
RELATIVELY QUIET ACROSS THE TERMINALS THIS MORNING...AND IS
GENERALLY EXPECTED TO REMAIN THIS WAY THROUGHOUT THE FORECAST
PERIOD. SURFACE TROUGH AND FRONT STILL REMAINING JUST TO THE WEST
OF THE TERMINALS BUT IS EXPECTED TO CONTINUE SHIFTING EAST ACROSS
NORTHERN ILLINOIS THIS MORNING. LATEST SATELLITE IMAGERY IS
DEPICTING SOME VFR CEILINGS DEVELOPING JUST AHEAD OF THIS FRONT
AND DO FEEL THAT A BRIEF PERIOD OF VFR CEILINGS IS POSSIBLE BEFORE
THIS FROPA. WITH A VERY WARM AND MOIST AIRMASS STILL IN
PLACE...SCATTERED FOG DEVELOPMENT IS ALSO POSSIBLE OUT AHEAD OF
THIS FRONT. PRECIP DEVELOPMENT DOES REMAIN POSSIBLE IN THE NEAR
TERM...BUT IF PRECIP DOES DEVELOP THE BULK OF IT SHOULD REMAIN
JUST SOUTH OF THE TERMINALS. SOUTHWEST WINDS WILL VEER TO THE WEST
AND THEN THE NORTHWEST WITH FROPA THIS MORNING...AND THEN INCREASE
WITH SOME GUSTS TO THE UPPER TEENS POSSIBLE BY MID/LATE MORNING.
WITH THE WIND DIRECTION ORIENTED OUT OF THE NORTH NORTHWEST BY MID
DAY...IT WOULDNT TAKE MUCH FOR THE WINDS TO FLOP OVER TO THE
NORTHEAST WITH THE LAKE INFLUENCE. SO HAVE INTRODUCED A WIND SHIFT
TO THE NORTHEAST BY 20Z THIS AFTERNOON...BUT WILL CONTINUE TO
MONITOR TRENDS THIS MORNING AS IT COULD EASILY BE AN HOUR TO
EARLIER THAN 20Z.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* HIGH CONFIDENCE WITH CEILING/VIS TRENDS.
* HIGH CONFIDENCE WITH PRECIP TRENDS EARLY THIS MORNING.
* MEDIUM HIGH CONFIDENCE WITH WIND SPEED/DIRECTION.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
THU THROUGH SUN...VFR. NO SIG WX.
MON...VFR. SLGT CHANCE TSRA
TRS
&&
.MARINE...
416 AM CDT
AS A TROUGH OF LOW PRESSURE AND ASSOCIATED COLD FRONT BEGIN TO
PUSH EAST ACROSS THE NORTHERN PORTIONS OF THE LAKE THIS
MORNING...A FAIRLY TIGHT PRESSURE GRADIENT HAS HELPED SOUTHWEST
WINDS TO INCREASE TO 15 TO 25 KT OVER THE NORTHERN PORTIONS OF THE
LAKE WHILE AREAS FURTHER SOUTH ARE OBSERVING SPEEDS OF 10 TO 20
KT. AS THIS TROUGH/FRONT CONTINUE SOUTHEAST DOWN THE LAKE THIS
MORNING...EXPECT THESE SOUTHWEST WINDS TO SHIFT TO THE
WEST/NORTHWEST AND THEN HOLD ONTO A NORTHWEST DIRECTION FOR THE
REMAINDER OF THE DAY INTO TONIGHT. EXPECT LIGHT NORTHERLY FLOW
OVER THE LAKE FOR MOST OF THURSDAY AS HIGH PRESSURE SLOWLY SHIFTS
EAST TOWARDS THE CENTRAL GREAT LAKES. BY FRIDAY WINDS TURN BACK TO
A SOUTHERLY DIRECTION...AS THIS HIGH SETTLES OVER THE EASTERN
GREAT LAKES INTO THE WEEKEND.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
403 AM CDT WED JUL 10 2013
.DISCUSSION...
305 AM CDT
FORECAST CHALLENGES THIS WEDNESDAY MORNING INCLUDE STILL AWAITING
THE ARRIVAL OF CONVECTION. JOKING ASIDE...IT IS IMPRESSIVE TO GET
THROUGH THIS VERY HIGH PWAT AND UNSTABLE AIR ALOFT /MUCAPES
2000-3500 J/KG/ WITHOUT CONVECTION FROM MIDDAY YESTERDAY THROUGH
LAST NIGHT. IT REMINDED HOW IMPORTANT THE TIMING OF A TRIGGER OR
SOME FORM OF FOCI ARE FOR CONVECTION...OR INHIBITING DEVELOPMENT IF
IN THE WAKE OF SUCH FEATURES. BUT BACK TO THE CHALLENGES GOING
FORWARD...THERE IS A CHANCE FOR CONVECTION THIS MORNING SOUTH OF
I-80 AS THE SURFACE TROUGH /A FOCUS!/ TAPS THE LAST OF THE MOIST AND
UNSTABLE AIR. THEN ATTENTION TURNS TO HOW QUICKLY TEMPERATURES WILL
WARM AFTER THE SEASONAL AIR ON THU AND FRI.
THIS MORNING...WELL-DEFINED UPPER TROUGH ACROSS WESTERN ONTARIO TO
NORTHERN IA IS PROGRESSING ESE. THE SURFACE TROUGH EXTENDS FROM A
1000MB LOW IN EASTERN ONTARIO TO THE QUAD CITIES AT 3 AM THIS
MORNING. DEW POINTS IN THE MID 70S ARE POOLED ACROSS THE AREA
OFFERING A MUGGY START TO THE DAY. SCATTERED ACCAS IS SEEN ON IR IN
THE REGION BUT NO SIGNS ON RADAR OR SATELLITE OF THIS DEVELOPING. A
SHORT WAVE IMPULSE SEEN ON WATER VAPOR AND 700MB PROFILER ANALYSIS
IS TRAVERSING SOUTHERN IA/NORTHERN MO...BASICALLY ALONG THE BASE
OF THE PRIMARY TROUGH. WHILE CONVECTIVE ALLOWING GUIDANCE SUCH AS
THE HRRR DOES HAVE CONVECTIVE DEVELOPMENT TRAVERSING THE FAR
SOUTHERN FORECAST AREA WITH THIS AND ALONG THE SURFACE BOUNDARY
DURING MID-MORNING...RADAR TRENDS SHOW SUBTLE ECHOES FURTHER SOUTH.
THE LOW-LEVEL JET HAS VEERED AND THE MORE SUBSTANTIAL MOISTURE
TRANSPORT HAS ALSO ENDED EARLY THIS MORNING...SO NOT SEEING TOO MUCH
HAPPENING. SO ONLY MAINTAINED LOW T-STORM CHANCES IN THE SOUTHERN
FORECAST AREA.
THIS AFTERNOON INTO TONIGHT...SUBSTANTIAL COLUMN DRYING IS FORECAST
AS THE AFTERNOON PROGRESSES. SURFACE DEW POINTS WILL FALL SLOWLY
THROUGH THE 60S AND WILL LIKELY STILL SUPPORT AT LEAST FEW AND
POTENTIALLY SCATTERED CU. THE 850MB TEMPERATURES IN THE MID-UPPER
TEENS FORECAST AT 18Z ACROSS THE FORECAST AREA...ALONG WITH THE WARM
STARTING POINT FOR TEMPERATURES...INDICATE MANY COMMUNITIES
REACHING THE MID AND POTENTIALLY UPPER 80S. AREAS NEAR THE WI STATE
LINE ARE MORE LIKELY TO FLAT-LINE IN TEMPERATURES THIS AFTERNOON AS
THE COOL FRONT PORTION OF THIS TROUGH WORKS THROUGH. NORTHWEST WINDS
IN THE BOUNDARY LAYER WILL BE RIGHT AT THE CUSP AT KEEPING A LAKE
BREEZE AT BAY FOR CHICAGO BUT SOME COOLING OF SEVERAL DEGREES COULD
BE SEEN BY MID-AFTERNOON IMMEDIATELY NEAR THE IL LAKESHORE AND
DEFINITELY NEAR THE IN SHORE.
THURSDAY THROUGH FRIDAY...A QUIET TIME AS SURFACE HIGH PRESSURE ON
THE ORDER OF 1019 MB MOVES ATOP THE AREA. THERE SHOULD BE LIMITED
CIRRUS AND ONLY FEW CU DURING THE AFTERNOONS. A MODEL BLEND
TYPICALLY DOES VERY WELL FOR TEMPS IN THIS TYPE OF CALM REGIME AND
HAVE BLENDED THAT WITH GOING FORECAST. TEMPERATURES SHOULD BE
WITHIN A COUPLE DEGREES OF OR RIGHT AT NORMAL.
THIS WEEKEND INTO EARLY NEXT WEEK...THE TREND IN LONG RANGE GUIDANCE
CONTINUES TO POINT TOWARD A WARMER AND DRIER TIME THAN SOLUTIONS
FROM A COUPLE DAYS AGO WITH STOUT UPPER RIDGING FROM THE WEST
SOUTHWEST STRETCHING OVER THE AREA. THE ADVANCING RIDGE FROM THE
WEST LATE THIS WEEK GETS HELD UP WITH BOTH A CLOSED LOW IN THE
NORTHEAST/MID-ATLANTIC AND TROPICAL STORM CHANTAL...FORECAST BY NHC
TO BE NEAR THE GA/SC SHORE BY LATE SUNDAY. 500MB HEIGHTS IN EXCESS
OF 594DM ARE FORECAST BY BOTH THE EC AN GFS FOR THE WEEKEND. WHILE
THE EC WEAKENS THIS MORE THAN THE GFS EARLY NEXT WEEK...THE PATTERN
FORECAST IS STILL BLOCKED AND RIDGE RIDING ACTIVITY IS FORECAST FOR
MOST OF THIS TIME FAIRLY FAR NORTH. BUT AS WE SAW IN THE JUNE 22-26
STRETCH...THAT CAN EVOLVE FURTHER SOUTH THAN LONG RANGE SOLUTIONS
SHOW AS MULTIPLE ROUNDS OF CONVECTION FIRE. BUT THIS IS CERTAINLY A
STRONGER RIDGE FORECAST THIS FAR NORTHEAST. THE 850MB 20C TEMP
CONTOUR FLIRTS WITH THE CWA ON BOTH SOLUTIONS FROM SAT THROUGH TUE.
HAVE BOOSTED TEMPS A COUPLE DEGREES FURTHER AND IF THAT THERMAL
RIDGE ENDS UP FURTHER SOUTH UNCONTAMINATED WITH CONVECTIVE
CLOUDS...CAN CERTAINLY ENVISION AT LEAST LOW 90S AWAY FROM THE LAKE
FOR MULTIPLE DAYS. BUT CONFIDENCE ENVELOPE...WHILE NOT OVERLY
LARGE...IS CENTERED MORE ON UPPER 80S /LOW-MID NEAR THE LAKE/. THE
EASTERN ATLANTIC/GULF FLOW LOOKS TO RETURN HIGHER DEW POINTS BY SUN
OR MON.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* BRIEF PERIOD OF VFR CEILINGS AND VIS EARLY THIS MORNING.
* ISOLATED SHRA ACROSS THE AREA EARLY THIS MORNING...BUT WITH A
LOW CHANCE FOR ANY PRECIP TO MOVE OVER THE TERMINALS.
* SOUTHWEST WINDS SHIFTING TO THE WEST/NORTHWEST WITH FROPA EARLY
THIS MORNING...WITH LAKE INFLUENCE TURNING THE WINDS NORTHEAST
IN THE AFTERNOON.
RODRIGUEZ
//DISCUSSION...UPDATED 06Z...
RELATIVELY QUIET ACROSS THE TERMINALS THIS MORNING...AND IS
GENERALLY EXPECTED TO REMAIN THIS WAY THROUGHOUT THE FORECAST
PERIOD. SURFACE TROUGH AND FRONT STILL REMAINING JUST TO THE WEST
OF THE TERMINALS BUT IS EXPECTED TO CONTINUE SHIFTING EAST ACROSS
NORTHERN ILLINOIS THIS MORNING. LATEST SATELLITE IMAGERY IS
DEPICTING SOME VFR CEILINGS DEVELOPING JUST AHEAD OF THIS FRONT
AND DO FEEL THAT A BRIEF PERIOD OF VFR CEILINGS IS POSSIBLE BEFORE
THIS FROPA. WITH A VERY WARM AND MOIST AIRMASS STILL IN
PLACE...SCATTERED FOG DEVELOPMENT IS ALSO POSSIBLE OUT AHEAD OF
THIS FRONT. PRECIP DEVELOPMENT DOES REMAIN POSSIBLE IN THE NEAR
TERM...BUT IF PRECIP DOES DEVELOP THE BULK OF IT SHOULD REMAIN
JUST SOUTH OF THE TERMINALS. SOUTHWEST WINDS WILL VEER TO THE WEST
AND THEN THE NORTHWEST WITH FROPA THIS MORNING...AND THEN INCREASE
WITH SOME GUSTS TO THE UPPER TEENS POSSIBLE BY MID/LATE MORNING.
WITH THE WIND DIRECTION ORIENTED OUT OF THE NORTH NORTHWEST BY MID
DAY...IT WOULDNT TAKE MUCH FOR THE WINDS TO FLOP OVER TO THE
NORTHEAST WITH THE LAKE INFLUENCE. SO HAVE INTRODUCED A WIND SHIFT
TO THE NORTHEAST BY 20Z THIS AFTERNOON...BUT WILL CONTINUE TO
MONITOR TRENDS THIS MORNING AS IT COULD EASILY BE AN HOUR TO
EARLIER THAN 20Z.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* HIGH CONFIDENCE WITH CEILING/VIS TRENDS.
* HIGH CONFIDENCE WITH PRECIP TRENDS EARLY THIS MORNING.
* MEDIUM HIGH CONFIDENCE WITH WIND SPEED/DIRECTION.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
THU THROUGH SUN...VFR. NO SIG WX.
MON...VFR. SLGT CHANCE TSRA
TRS
&&
.MARINE...
250 PM CDT
THE WEAK HIGH AND LOW ARE OVER SOUTHERN MI AND WILL CONTINUE TO
DISSIPATE. A BROAD TROUGH OF LOW PRESSURE EXTENDS FROM NORTHERN
ONTARIO THROUGH THE CENTRAL PLAINS AND IT WILL SLIDE OVER THE LAKE
TONIGHT AND ITS COLD FRONT WILL ALSO SLIDE OVER THE LAKE LATE
TONIGHT/EARLY WED MORNING. FOG HAS DISSIPATED OVER THE SOUTHERN
HALF OF THE LAKE BUT IS HOLDING STRONG OVER THE NORTHERN HALF.
THINKING THE FOG WILL DISSIPATE AS SHOWERS MOVE OVER THE NORTHERN
HALF OF THE LAKE...BUT DENSE FOG MAY STICK AROUND OVER THE NORTH
HALF OF THE LAKE UNTIL THE FRONT MOVES THROUGH EARLY WED MORNING.
FOR NOW EXTENDED THE DENSE FOG ADVISORY THROUGH 9PM TONIGHT FOR
AREAS NORTH OF A LINE CONNECTING SHEBOYGAN WI TO PENTWATER MI.
WINDS TURN W TO NW BEHIND THE FRONT AND THEN WEAKEN/BECOME MORE
VARIABLE LATE ON THURSDAY AS THE HIGH MOVES OVER THE LAKE. THE HIGH
CONTINUES TO MOVE EAST OF THE LAKE ON FRIDAY WITH SE TO S WINDS
EXPECTED ACROSS THE LAKE. WHILE THE HIGHS CENTER MOVES OVER NEW
ENGLAND FRIDAY NIGHT/SATURDAY MORNING...S WINDS ARE EXPECTED THROUGH
THE REST OF THE FORECAST PERIOD.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
308 AM CDT WED JUL 10 2013
.DISCUSSION...
305 AM CDT
FORECAST CHALLENGES THIS WEDNESDAY MORNING INCLUDE STILL AWAITING
THE ARRIVAL OF CONVECTION. JOKING ASIDE...IT IS IMPRESSIVE TO GET
THROUGH THIS VERY HIGH PWAT AND UNSTABLE AIR ALOFT /MUCAPES
2000-3500 J/KG/ WITHOUT CONVECTION FROM MIDDAY YESTERDAY THROUGH
LAST NIGHT. IT REMINDED HOW IMPORTANT THE TIMING OF A TRIGGER OR
SOME FORM OF FOCI ARE FOR CONVECTION...OR INHIBITING DEVELOPMENT IF
IN THE WAKE OF SUCH FEATURES. BUT BACK TO THE CHALLENGES GOING
FORWARD...THERE IS A CHANCE FOR CONVECTION THIS MORNING SOUTH OF
I-80 AS THE SURFACE TROUGH /A FOCUS!/ TAPS THE LAST OF THE MOIST AND
UNSTABLE AIR. THEN ATTENTION TURNS TO HOW QUICKLY TEMPERATURES WILL
WARM AFTER THE SEASONAL AIR ON THU AND FRI.
THIS MORNING...WELL-DEFINED UPPER TROUGH ACROSS WESTERN ONTARIO TO
NORTHERN IA IS PROGRESSING ESE. THE SURFACE TROUGH EXTENDS FROM A
1000MB LOW IN EASTERN ONTARIO TO THE QUAD CITIES AT 3 AM THIS
MORNING. DEW POINTS IN THE MID 70S ARE POOLED ACROSS THE AREA
OFFERING A MUGGY START TO THE DAY. SCATTERED ACCAS IS SEEN ON IR IN
THE REGION BUT NO SIGNS ON RADAR OR SATELLITE OF THIS DEVELOPING. A
SHORT WAVE IMPULSE SEEN ON WATER VAPOR AND 700MB PROFILER ANALYSIS
IS TRAVERSING SOUTHERN IA/NORTHERN MO...BASICALLY ALONG THE BASE
OF THE PRIMARY TROUGH. WHILE CONVECTIVE ALLOWING GUIDANCE SUCH AS
THE HRRR DOES HAVE CONVECTIVE DEVELOPMENT TRAVERSING THE FAR
SOUTHERN FORECAST AREA WITH THIS AND ALONG THE SURFACE BOUNDARY
DURING MID-MORNING...RADAR TRENDS SHOW SUBTLE ECHOES FURTHER SOUTH.
THE LOW-LEVEL JET HAS VEERED AND THE MORE SUBSTANTIAL MOISTURE
TRANSPORT HAS ALSO ENDED EARLY THIS MORNING...SO NOT SEEING TOO MUCH
HAPPENING. SO ONLY MAINTAINED LOW T-STORM CHANCES IN THE SOUTHERN
FORECAST AREA.
THIS AFTERNOON INTO TONIGHT...SUBSTANTIAL COLUMN DRYING IS FORECAST
AS THE AFTERNOON PROGRESSES. SURFACE DEW POINTS WILL FALL SLOWLY
THROUGH THE 60S AND WILL LIKELY STILL SUPPORT AT LEAST FEW AND
POTENTIALLY SCATTERED CU. THE 850MB TEMPERATURES IN THE MID-UPPER
TEENS FORECAST AT 18Z ACROSS THE FORECAST AREA...ALONG WITH THE WARM
STARTING POINT FOR TEMPERATURES...INDICATE MANY COMMUNITIES
REACHING THE MID AND POTENTIALLY UPPER 80S. AREAS NEAR THE WI STATE
LINE ARE MORE LIKELY TO FLAT-LINE IN TEMPERATURES THIS AFTERNOON AS
THE COOL FRONT PORTION OF THIS TROUGH WORKS THROUGH. NORTHWEST WINDS
IN THE BOUNDARY LAYER WILL BE RIGHT AT THE CUSP AT KEEPING A LAKE
BREEZE AT BAY FOR CHICAGO BUT SOME COOLING OF SEVERAL DEGREES COULD
BE SEEN BY MID-AFTERNOON IMMEDIATELY NEAR THE IL LAKESHORE AND
DEFINITELY NEAR THE IN SHORE.
THURSDAY THROUGH FRIDAY...A QUIET TIME AS SURFACE HIGH PRESSURE ON
THE ORDER OF 1019 MB MOVES ATOP THE AREA. THERE SHOULD BE LIMITED
CIRRUS AND ONLY FEW CU DURING THE AFTERNOONS. A MODEL BLEND
TYPICALLY DOES VERY WELL FOR TEMPS IN THIS TYPE OF CALM REGIME AND
HAVE BLENDED THAT WITH GOING FORECAST. TEMPERATURES SHOULD BE
WITHIN A COUPLE DEGREES OF OR RIGHT AT NORMAL.
THIS WEEKEND INTO EARLY NEXT WEEK...THE TREND IN LONG RANGE GUIDANCE
CONTINUES TO POINT TOWARD A WARMER AND DRIER TIME THAN SOLUTIONS
FROM A COUPLE DAYS AGO WITH STOUT UPPER RIDGING FROM THE WEST
SOUTHWEST STRETCHING OVER THE AREA. THE ADVANCING RIDGE FROM THE
WEST LATE THIS WEEK GETS HELD UP WITH BOTH A CLOSED LOW IN THE
NORTHEAST/MID-ATLANTIC AND TROPICAL STORM CHANTAL...FORECAST BY NHC
TO BE NEAR THE GA/SC SHORE BY LATE SUNDAY. 500MB HEIGHTS IN EXCESS
OF 594DM ARE FORECAST BY BOTH THE EC AN GFS FOR THE WEEKEND. WHILE
THE EC WEAKENS THIS MORE THAN THE GFS EARLY NEXT WEEK...THE PATTERN
FORECAST IS STILL BLOCKED AND RIDGE RIDING ACTIVITY IS FORECAST FOR
MOST OF THIS TIME FAIRLY FAR NORTH. BUT AS WE SAW IN THE JUNE 22-26
STRETCH...THAT CAN EVOLVE FURTHER SOUTH THAN LONG RANGE SOLUTIONS
SHOW AS MULTIPLE ROUNDS OF CONVECTION FIRE. BUT THIS IS CERTAINLY A
STRONGER RIDGE FORECAST THIS FAR NORTHEAST. THE 850MB 20C TEMP
CONTOUR FLIRTS WITH THE CWA ON BOTH SOLUTIONS FROM SAT THROUGH TUE.
HAVE BOOSTED TEMPS A COUPLE DEGREES FURTHER AND IF THAT THERMAL
RIDGE ENDS UP FURTHER SOUTH UNCONTAMINATED WITH CONVECTIVE
CLOUDS...CAN CERTAINLY ENVISION AT LEAST LOW 90S AWAY FROM THE LAKE
FOR MULTIPLE DAYS. BUT CONFIDENCE ENVELOPE...WHILE NOT OVERLY
LARGE...IS CENTERED MORE ON UPPER 80S /LOW-MID NEAR THE LAKE/. THE
EASTERN ATLANTIC/GULF FLOW LOOKS TO RETURN HIGHER DEW POINTS BY SUN
OR MON.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* BRIEF PERIOD OF VFR CEILINGS AND VIS EARLY THIS MORNING.
* ISOLATED SHRA ACROSS THE AREA EARLY THIS MORNING...BUT WITH A
LOW CHANCE FOR ANY PRECIP TO MOVE OVER THE TERMINALS.
* SOUTHWEST WINDS SHIFTING TO THE WEST/NORTHWEST WITH FROPA EARLY
THIS MORNING...WITH LAKE INFLUENCE TURNING THE WINDS NORTHEAST
IN THE AFTERNOON.
RODRIGUEZ
//DISCUSSION...UPDATED 06Z...
RELATIVELY QUIET ACROSS THE TERMINALS THIS MORNING...AND IS
GENERALLY EXPECTED TO REMAIN THIS WAY THROUGHOUT THE FORECAST
PERIOD. SURFACE TROUGH AND FRONT STILL REMAINING JUST TO THE WEST
OF THE TERMINALS BUT IS EXPECTED TO CONTINUE SHIFTING EAST ACROSS
NORTHERN ILLINOIS THIS MORNING. LATEST SATELLITE IMAGERY IS
DEPICTING SOME VFR CEILINGS DEVELOPING JUST AHEAD OF THIS FRONT
AND DO FEEL THAT A BRIEF PERIOD OF VFR CEILINGS IS POSSIBLE BEFORE
THIS FROPA. WITH A VERY WARM AND MOIST AIRMASS STILL IN
PLACE...SCATTERED FOG DEVELOPMENT IS ALSO POSSIBLE OUT AHEAD OF
THIS FRONT. PRECIP DEVELOPMENT DOES REMAIN POSSIBLE IN THE NEAR
TERM...BUT IF PRECIP DOES DEVELOP THE BULK OF IT SHOULD REMAIN
JUST SOUTH OF THE TERMINALS. SOUTHWEST WINDS WILL VEER TO THE WEST
AND THEN THE NORTHWEST WITH FROPA THIS MORNING...AND THEN INCREASE
WITH SOME GUSTS TO THE UPPER TEENS POSSIBLE BY MID/LATE MORNING.
WITH THE WIND DIRECTION ORIENTED OUT OF THE NORTH NORTHWEST BY MID
DAY...IT WOULDNT TAKE MUCH FOR THE WINDS TO FLOP OVER TO THE
NORTHEAST WITH THE LAKE INFLUENCE. SO HAVE INTRODUCED A WIND SHIFT
TO THE NORTHEAST BY 20Z THIS AFTERNOON...BUT WILL CONTINUE TO
MONITOR TRENDS THIS MORNING AS IT COULD EASILY BE AN HOUR TO
EARLIER THAN 20Z.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE WITH CEILING/VIS TRENDS.
* HIGH CONFIDENCE WITH PRECIP TRENDS EARLY THIS MORNING.
* MEDIUM HIGH CONFIDENCE WITH WIND SPEED/DIRECTION.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
THU THROUGH SUN...VFR. NO SIG WX.
MON...VFR. SLGT CHANCE TSRA
TRS
&&
.MARINE...
250 PM CDT
THE WEAK HIGH AND LOW ARE OVER SOUTHERN MI AND WILL CONTINUE TO
DISSIPATE. A BROAD TROUGH OF LOW PRESSURE EXTENDS FROM NORTHERN
ONTARIO THROUGH THE CENTRAL PLAINS AND IT WILL SLIDE OVER THE LAKE
TONIGHT AND ITS COLD FRONT WILL ALSO SLIDE OVER THE LAKE LATE
TONIGHT/EARLY WED MORNING. FOG HAS DISSIPATED OVER THE SOUTHERN
HALF OF THE LAKE BUT IS HOLDING STRONG OVER THE NORTHERN HALF.
THINKING THE FOG WILL DISSIPATE AS SHOWERS MOVE OVER THE NORTHERN
HALF OF THE LAKE...BUT DENSE FOG MAY STICK AROUND OVER THE NORTH
HALF OF THE LAKE UNTIL THE FRONT MOVES THROUGH EARLY WED MORNING.
FOR NOW EXTENDED THE DENSE FOG ADVISORY THROUGH 9PM TONIGHT FOR
AREAS NORTH OF A LINE CONNECTING SHEBOYGAN WI TO PENTWATER MI.
WINDS TURN W TO NW BEHIND THE FRONT AND THEN WEAKEN/BECOME MORE
VARIABLE LATE ON THURSDAY AS THE HIGH MOVES OVER THE LAKE. THE HIGH
CONTINUES TO MOVE EAST OF THE LAKE ON FRIDAY WITH SE TO S WINDS
EXPECTED ACROSS THE LAKE. WHILE THE HIGHS CENTER MOVES OVER NEW
ENGLAND FRIDAY NIGHT/SATURDAY MORNING...S WINDS ARE EXPECTED THROUGH
THE REST OF THE FORECAST PERIOD.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS LINCOLN IL
204 AM CDT WED JUL 10 2013
.DISCUSSION...
ISSUED 204 AM CDT WED JUL 10 2013
ONE MORE DAY OF POTENTIAL STORM CHANCES...BEFORE AN EXTENDED
PERIOD OF DRY WEATHER ARRIVES ACROSS CENTRAL ILLINOIS.
SHORT TERM...TODAY THROUGH FRIDAY
06Z/1AM SURFACE MAP SHOWS LOW PRESSURE OVER LAKE SUPERIOR...WITH
TRAILING COLD FRONT EXTENDING SOUTHWESTWARD ACROSS EASTERN IOWA
INTO FAR NORTHERN KANSAS. ALOFT...VIGOROUS SHORT-WAVE IS EVIDENT
ON WATER VAPOR IMAGERY OVER MINNESOTA...WHILE A WEAKER WAVE IS
NOTED OVER NEBRASKA/KANSAS. CONVECTION DURING THE OVERNIGHT HOURS
HAS BEEN TIED TO THE SOUTHERN WAVE IN CONJUNCTION WITH A 30KT LLJ
FLOWING NORTHEASTWARD FROM THE SOUTHERN PLAINS. RESULTING
CONVECTIVE COMPLEX CURRENTLY OVER NORTHEAST KANSAS IS EXPECTED TO
TRACK E/SE INTO MISSOURI DURING THE PRE-DAWN HOURS...STAYING OFF
TO THE W/SW OF CENTRAL ILLINOIS. MEANWHILE...WIDELY SCATTERED
SHOWERS AND THUNDERSTORMS WILL DEVELOP FURTHER NORTHEAST INTO
CENTRAL ILLINOIS WITHIN THE WEAK LLJ AXIS. LATEST RADAR IMAGERY
SHOWS CONVECTION BEGINNING TO DEVELOP ACROSS CENTRAL MISSOURI INTO
SOUTHWEST ILLINOIS...AND EXPECT THIS TREND TO CONTINUE INTO THE
EARLY MORNING HOURS. MODELS HAVE BEEN HANDLING CONVECTIVE
DEVELOPMENT/EVOLUTION POORLY FOR THE PAST SEVERAL DAYS...AND THE
00Z JUL 10 SUITE IS NO EXCEPTION. WILL THEREFORE RELY MAINLY ON
LATEST SATELLITE/RADAR DATA AND CONSISTENCY FOR THE IMMEDIATE
SHORT-TERM FORECAST. AS SUCH...THINK SCATTERED SHOWERS/STORMS WILL
CONTINUE TO DEVELOP NORTHEASTWARD ACROSS AT LEAST THE SOUTHERN
TWO-THIRDS OF THE KILX CWA THIS MORNING. AS COLD FRONT SAGS
SOUTHWARD TO NEAR THE I-72 CORRIDOR BY MIDDAY...RAIN THREAT WILL
ESSENTIALLY COME TO AN END ALONG AND NORTH OF A RUSHVILLE TO
BLOOMINGTON-NORMAL LINE THIS AFTERNOON. FURTHER SOUTH...SEVERAL
HIGH-RES MODELS ARE HINTING THAT AT LEAST A BROKEN LINE OF
CONVECTION WILL DEVELOP IN THE HIGHLY UNSTABLE AIRMASS ALONG/SOUTH
OF THE BOUNDARY. GIVEN HIGH CAPE VALUES OF AROUND 4000J/KG AND
SLIGHT COOLING ALOFT ASSOCIATED WITH MINNESOTA SHORT-WAVE TRACKING
INTO THE GREAT LAKES...THINK THIS IS A REASONABLE SOLUTION. AS A
RESULT...WILL CARRY CHANCE POPS ACROSS THE BOARD DURING THE
MORNING HOURS...THEN WILL FOCUS LIKELY POPS ALONG/SOUTH OF A PARIS
TO TAYLORVILLE LINE THIS AFTERNOON. WILL BE ANOTHER WARM AND HUMID
DAY...AS COOLER/DRIER AIRMASS WILL INITIALLY BE RATHER SLOW TO
ARRIVE BEHIND FRONT. HIGHS WILL RANGE FROM THE MIDDLE 80S ACROSS
THE NORTH...TO THE LOWER 90S SOUTH OF I-70.
MOST MODELS DROP FRONT AND ANY LINGERING PRECIP CHANCES SOUTH OF
THE CWA BY EVENING...HOWEVER 00Z NAM NOW FEATURES A WEAK WAVE
ALONG THE BOUNDARY THAT BRIEFLY IMPEDES ITS SOUTHWARD PROGRESS.
SINCE THIS IS THE FIRST RUN THE WAVE HAS APPEARED ON...AND THERE
DOES NOT SEEM TO BE ANY SUPPORTING UPPER SUPPORT FOR IT...WILL
GENERALLY DISREGARD THIS SOLUTION. WILL HOWEVER HANG ON TO JUST A
SLIGHT CHANCE POP SOUTH OF I-70 INTO THE EVENING...IN CASE
AFTERNOON STORMS HAVE NOT DROPPED SOUTH/EAST OF THE CWA BY 00Z.
HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES FOR THURSDAY AND
FRIDAY...PROVIDING A COOL/DRY NORTHEASTERLY FLOW. HIGH
TEMPERATURES WILL ONLY REACH THE LOWER TO MIDDLE 80S BOTH
DAYS...WHILE OVERNIGHT LOWS DROP INTO THE UPPER 50S AND LOWER 60S.
IN ADDITION...RELATIVE HUMIDITY VALUES WILL BE CONSIDERABLY LOWER.
LONG TERM...SATURDAY THROUGH TUESDAY
GREAT LAKES UPPER TROUGH WILL SHIFT INTO NEW ENGLAND OVER THE
WEEKEND...WHILE UPPER RIDGE BUILDS INTO THE MIDWEST. WHILE SURFACE
RIDGING WILL MAINTAIN AN E/SE LOW-LEVEL FLOW THROUGH
SUNDAY...RISING UPPER HEIGHTS AND FULL JULY SUNSHINE WILL QUICKLY
MODIFY THE AIRMASS. AS A RESULT...HIGH TEMPERATURES WILL CLIMB
BACK INTO THE UPPER 80S BY SUNDAY. AS SURFACE RIDGE SHIFTS FURTHER
AWAY...A DEVELOPING SOUTHERLY FLOW WILL BRING THE HUMIDITY BACK
INTO THE PICTURE EARLY NEXT WEEK. WITH HIGH TEMPS REACHING THE 90
DEGREE MARK AND DEWPOINTS RISING INTO THE 70S...HEAT INDEX VALUES
WILL LIKELY APPROACH 100 DEGREES AGAIN BY MONDAY AND TUESDAY. RAIN
CHANCES WILL BE SLIM TO NONE THROUGH THE EXTENDED AND BEYOND...AS
E/W ORIENTED UPPER RIDGE ACROSS THE MIDWEST WILL KEEP MAIN STORM
TRACK AND BEST CHANCES FOR PRECIP WELL TO THE NORTH AND SOUTH OF
CENTRAL ILLINOIS.
BARNES
&&
.AVIATION...
ISSUED 1145 PM CDT TUE JUL 9 2013
DELAYED ONSET OF STORMS CONTINUES...AND THE 02Z HRRR CONTINUES TO
SHOW STORMS HOLDING OFF UNTIL AFTER 11Z-12Z FOR PIA...WITH A LINE
OF STORMS FROM SPI TO CMI IN PLACE AROUND 16Z-17Z. WE PUSHED THE
START OF ANY VCTS LATER IN THE TAF PERIOD TO MATCH THAT
PROGRESSION. STILL...THE STORMS WILL BE OF A SCATTERED
COVERAGE...SO ANY SHORT PERIOD IFR/LIFR DURING ANY THUNDERSTORMS
WAS LEFT OUT. EVEN MVFR WILL BE LIMITED TO ANY STORM PATHS ACROSS
THE AIRPORTS.
WE WILL CONTINUE THE VFR PREVAILING...UNTIL ANY STORMS DEVELOP
LATE TONIGHT OR WED MORNING. WINDS WILL START OUR
SOUTHWESTERLY...THEN VEER TO THE NW AFTER FROPA. BY WED
AFTERNOON...TURBULENT MIXING WILL PUSH SUSTAINED WINDS IN THE
10-15KT RANGE. WINDS WILL SUBSIDE BY SUNSET...BUT REMAIN NORTH
THROUGH 06Z WED NIGHT.
SHIMON
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1257 AM CDT WED JUL 10 2013
.DISCUSSION...
900 PM CDT
NOT MUCH CHANGE TO PREVIOUS THINKING. VERY MOIST AND UNSTABLE
AIRMASS STILL IN PLACE BUT WEAKLY CAPPED. WITH SHORT WAVE OVER THE
IL/IN BORDER DEPARTING TO THE EAST THIS EVENING...LITTLE SUPPORT
FOR ORGANIZED CONVECTION THIS EVENING. 0-6KM BULK SHEAR AROUND 30
KT SHOULD INCREASE SOME OVERNIGHT AS STRONG WAVE OVER MN CONTINUES
TO DIG INTO THE GREAT LAKES. MAY STILL GET SOME SCATTERED
CONVECTION WITH COLD FRONT LATER TONIGHT. A COUPLE CELLS SHOWING
UP OVER NORTHEAST IA ATTM. HRRR AND OTHER SHORT RANGE GUIDANCE
STILL SUGGESTING SOME SCATTERED ACTIVITY OVERNIGHT. BUT LOOKS LIKE
MORE ORGANIZED STORMS OVER NE/KS WILL DRIVE E ACROSS MO INTO
CENTRAL IL BY MORNING. WILL MAINTAIN LOW END POPS OVERNIGHT.
ALLSOPP
//PREV DISCUSSION...
250 PM CDT
SHORT TERM...THIS EVENING THROUGH FRIDAY...
SEVERE WEATHER/HEAVY RAINFALL POTENTIAL APPEARS TO BE DIMINISHING
SIGNIFICANTLY ACROSS THE FORECAST AREA THROUGH TONIGHT.
PERSISTENT ELEVATED CONVECTION AND ASSOCIATED CLOUD SHIELD HAS
LIMITED STRONG DESTABILIZATION ACROSS MUCH OF THE CWA INTO THIS
AFTERNOON. THIS...ALONG WITH A LACK OF STRONGER MID-LEVEL WINDS/DEEP
SHEAR (WHICH WAS LAGGING SHORT WAVE FORCING ACROSS THE REGION)
APPEARS TO HAVE DECREASED OUR POTENTIAL FOR STRONG/SEVERE
THUNDERSTORMS ACROSS MUCH OF THE CWA THROUGH TONIGHT.
AFTERNOON SURFACE ANALYSIS DEPICTS LOW PRESSURE OVER NORTHWEST WI
WITH A WARM FRONTAL BOUNDARY EXTENDING SOUTHEAST TO SOUTHEAST
WI/SOUTHERN LAKE MICHIGAN. A COLD FRONT TRAILED FROM THE LOW TO
NORTHWESTERN IA AND CENTRAL KS. THE WARM SECTOR ACROSS CENTRAL IL
WAS CHARACTERIZED BY TEMPS NEAR 90 AND DEW POINT TEMPS IN THE
LOW-MID 70S...WHILE PERSISTENT CLOUDS/PRECIP HAVE HELD TEMPS INTO
THE MID 70S-LOWER 80S ACROSS MUCH OF THE WFO LOT CWA. OUR COOLER
BOUNDARY LAYER IS CLEARLY SHOWN IN AMDAR AIRCRAFT ASCENT SOUNDINGS
FROM KMDW THIS AFTERNOON...AND SUPPORT SPC/RAP MESOANALYSIS DATA
WHICH INDICATES A FAIRLY SUBSTANTIAL CAP IN PLACE ACROSS NORTHERN IL
FOR SURFACE/NEAR SURFACE BASED PARCELS. AFTERNOON GOES SATELLITE
WATER VAPOR IMAGERY INDICATES A SHORT-WAVE TROUGH APPROACHING THE
MISSISSIPPI RIVER ACROSS MN/WI AND EASTERN IA AT THIS HOUR...WITH A
VORT/MCV NOTED OVER SOUTHEAST IA. THIS SHOULD TRACK ACROSS THE WFO
LOT CWA BETWEEN ROUGHLY 21-01Z AND MAY SERVE AS A TRIGGER FOR AN
INCREASE IN CONVECTION ESPECIALLY SOUTH OF I-80...WHICH RAP/HRRR
RUNS HAVE BEEN DEPICTING. APPROACH OF MODEST MID-LEVEL SPEED MAX
AROUND 35 KT WOULD SUPPORT AN INCREASE IN EFFECTIVE BULK SHEAR
VALUES TO 30-35 KT...WHICH MAY HELP ANY DEVELOPING CONVECTION BECOME
BETTER ORGANIZED AND PERHAPS PRESENT A DAMAGING WIND THREAT ACROSS
THE SOUTHERN CWA THROUGH THE LATE AFTERNOON. MID-LEVEL FEATURE LOOKS
TO MOVE EAST OF THE CWA BY 01Z OR SO...WITH THUNDERSTORM THREAT
SHIFTING LARGELY OFF TO THE EAST/SOUTH OF THE AREA BEYOND THAT TIME.
ANY STORMS THAT DO DEVELOP WILL CONTINUE TO PRESENT A HEAVY RAINFALL
THREAT...WITH PWATS RIGHT AROUND 2 INCHES.
STRONGER SHORT WAVE TROUGH AND JET MAX FEATURE OVER THE NORTHERN
PLAINS THIS AFTERNOON WILL PROPAGATE EAST-SOUTHEAST INTO THE WESTERN
GREAT LAKES REGION BY WEDNESDAY MORNING...WITH MAIN AREA OF SURFACE
LOW PRESSURE DEEPENING AND LIFTING ACROSS THE NORTHERN LAKES
OVERNIGHT AND TRAILING THE AFOREMENTIONED COLD FRONT INTO NORTHERN
IL LATE. WHILE SOME POTENTIAL FOR ADDITIONAL SHOWERS/THUNDERSTORMS
CANT BE RULED OUT OVERNIGHT (POTENTIAL FOR DEVELOPMENT LATE THIS
AFTERNOON MOST LIKELY OVER SOUTHEAST MN/WESTERN WI) UPSTREAM
SOUNDINGS FROM ABR/OAX INDICATE SUBSTANTIAL DRY AIR ALOFT BEHIND
LEAD SHORT WAVE OVER EASTERN IA...AND GUIDANCE HAS TRENDED MUCH
DRIER AFTER INITIAL WAVE PASSES EARLY THIS EVENING. THUS HAVE
ELECTED TO MAINTAIN SOME SLIGHT CHANCE POPS OVERNIGHT WITH ARRIVAL
OF SURFACE FRONT AND LARGE SCALE FORCING FROM DIGGING NORTHERN
PLAINS WAVE...THOUGH SUSPECT THAT THE POTENTIAL FOR STRONG
THUNDERSTORMS AND ANY SEVERE/HEAVY RAIN THREAT WILL BE LIMITED TO
THE LATE AFTERNOON AND EARLY EVENING HOURS. COLD FRONT THEN
CONTINUES TO PUSH SOUTHEAST ACROSS THE FORECAST AREA WEDNESDAY
MORNING...ENDING PRECIP THREAT FROM THE NORTHWEST.
AFTER ANOTHER WARM/MUGGY NIGHT AHEAD OF THE FRONT TONIGHT...SOMEWHAT
COOLER AND DRIER AIR WILL FILTER INTO THE AREA WEDNESDAY. NORTHERN
COUNTIES WILL LIKELY SEE HIGHS IN THE UPPER 70S/LOW 80S WHILE THE
SOUTH REMAINS A LITTLE MUGGIER IN THE MID/UPPER 80S. FULL EFFECTS OF
THE CHANGE IN AIR MASS WILL BE FELT THURSDAY AND FRIDAY...WITH
PLENTIFUL SUNSHINE AND UPPER 70S/LOW 80S CWA-WIDE...AND MID 70S
ALONG THE LAKE WITH MODEST ONSHORE FLOW.
RATZER
EXTENDED...FRIDAY NIGHT THROUGH MONDAY...
ALOFT THE LARGE HIGH OVER THE CENTRAL PLAINS STRENGTHENS AND GROWS
IN SIZE ACROSS THE MID MISSISSIPPI RIVER VALLEY. AT THE SURFACE
HIGH PRESSURE OVER THE EASTERN GREAT LAKES SHIFTS EAST OVER NEW
ENGLAND. HOWEVER THE WESTERN EDGE OF THE HIGH REMAINS OVER THE
REGION KEEPING THE ZONAL FLOW AND A SERIES OF SHORTWAVE TROUGHS AND
WEAK LOWS TO OUR NORTH. THAT BEING SAID...IF THE HIGH SHIFTS SOUTH
THE SYSTEMS COULD EASILY MOVE THROUGH NORTHERN IL AND NW INDIANA.
AS IT STANDS NOW THE WEEKEND STARTS DRY WITH SHOWERS AND
THUNDERSTORMS POSSIBLE SUNDAY NIGHT/MONDAY MAINLY ALONG THE IL/WI
STATE LINE AS A SURFACE TROUGH PASSES THROUGH THE REGION. HIGH
PRESSURE REESTABLISHES ITSELF ACROSS NORTHERN IL MONDAY NIGHT WITH
DRY CONDITIONS EXPECTED FOR THE BEGINNING OF THE WORK WEEK.
CONTINUED HOT AND MUGGY CONDITIONS ARE EXPECTED WITH TEMPS IN THE
MID TO UPPER 80S AND DEWPOINTS IN THE 60S-70S THROUGHOUT THE
EXTENDED.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* BRIEF PERIOD OF VFR CEILINGS AND VIS EARLY THIS MORNING.
* ISOLATED SHRA ACROSS THE AREA EARLY THIS MORNING...BUT WITH A
LOW CHANCE FOR ANY PRECIP TO MOVE OVER THE TERMINALS.
* SOUTHWEST WINDS SHIFTING TO THE WEST/NORTHWEST WITH FROPA EARLY
THIS MORNING...WITH LAKE INFLUENCE TURNING THE WINDS NORTHEAST
IN THE AFTERNOON.
RODRIGUEZ
//DISCUSSION...UPDATED 06Z...
RELATIVELY QUIET ACROSS THE TERMINALS THIS MORNING...AND IS
GENERALLY EXPECTED TO REMAIN THIS WAY THROUGHOUT THE FORECAST
PERIOD. SURFACE TROUGH AND FRONT STILL REMAINING JUST TO THE WEST
OF THE TERMINALS BUT IS EXPECTED TO CONTINUE SHIFTING EAST ACROSS
NORTHERN ILLINOIS THIS MORNING. LATEST SATELLITE IMAGERY IS
DEPICTING SOME VFR CEILINGS DEVELOPING JUST AHEAD OF THIS FRONT
AND DO FEEL THAT A BRIEF PERIOD OF VFR CEILINGS IS POSSIBLE BEFORE
THIS FROPA. WITH A VERY WARM AND MOIST AIRMASS STILL IN
PLACE...SCATTERED FOG DEVELOPMENT IS ALSO POSSIBLE OUT AHEAD OF
THIS FRONT. PRECIP DEVELOPMENT DOES REMAIN POSSIBLE IN THE NEAR
TERM...BUT IF PRECIP DOES DEVELOP THE BULK OF IT SHOULD REMAIN
JUST SOUTH OF THE TERMINALS. SOUTHWEST WINDS WILL VEER TO THE WEST
AND THEN THE NORTHWEST WITH FROPA THIS MORNING...AND THEN INCREASE
WITH SOME GUSTS TO THE UPPER TEENS POSSIBLE BY MID/LATE MORNING.
WITH THE WIND DIRECTION ORIENTED OUT OF THE NORTH NORTHWEST BY MID
DAY...IT WOULDNT TAKE MUCH FOR THE WINDS TO FLOP OVER TO THE
NORTHEAST WITH THE LAKE INFLUENCE. SO HAVE INTRODUCED A WIND SHIFT
TO THE NORTHEAST BY 20Z THIS AFTERNOON...BUT WILL CONTINUE TO
MONITOR TRENDS THIS MORNING AS IT COULD EASILY BE AN HOUR TO
EARLIER THAN 20Z.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE WITH CEILING/VIS TRENDS.
* HIGH CONFIDENCE WITH PRECIP TRENDS EARLY THIS MORNING.
* MEDIUM HIGH CONFIDENCE WITH WIND SPEED/DIRECTION.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
THU THROUGH SUN...VFR. NO SIG WX.
MON...VFR. SLGT CHANCE TSRA
TRS
&&
.MARINE...
250 PM CDT
THE WEAK HIGH AND LOW ARE OVER SOUTHERN MI AND WILL CONTINUE TO
DISSIPATE. A BROAD TROUGH OF LOW PRESSURE EXTENDS FROM NORTHERN
ONTARIO THROUGH THE CENTRAL PLAINS AND IT WILL SLIDE OVER THE LAKE
TONIGHT AND ITS COLD FRONT WILL ALSO SLIDE OVER THE LAKE LATE
TONIGHT/EARLY WED MORNING. FOG HAS DISSIPATED OVER THE SOUTHERN
HALF OF THE LAKE BUT IS HOLDING STRONG OVER THE NORTHERN HALF.
THINKING THE FOG WILL DISSIPATE AS SHOWERS MOVE OVER THE NORTHERN
HALF OF THE LAKE...BUT DENSE FOG MAY STICK AROUND OVER THE NORTH
HALF OF THE LAKE UNTIL THE FRONT MOVES THROUGH EARLY WED MORNING.
FOR NOW EXTENDED THE DENSE FOG ADVISORY THROUGH 9PM TONIGHT FOR
AREAS NORTH OF A LINE CONNECTING SHEBOYGAN WI TO PENTWATER MI.
WINDS TURN W TO NW BEHIND THE FRONT AND THEN WEAKEN/BECOME MORE
VARIABLE LATE ON THURSDAY AS THE HIGH MOVES OVER THE LAKE. THE HIGH
CONTINUES TO MOVE EAST OF THE LAKE ON FRIDAY WITH SE TO S WINDS
EXPECTED ACROSS THE LAKE. WHILE THE HIGHS CENTER MOVES OVER NEW
ENGLAND FRIDAY NIGHT/SATURDAY MORNING...S WINDS ARE EXPECTED THROUGH
THE REST OF THE FORECAST PERIOD.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ868 UNTIL 3 AM WEDNESDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS LINCOLN IL
1145 PM CDT TUE JUL 9 2013
.DISCUSSION...
ISSUED 900 PM CDT TUE JUL 9 2013
TOUGH CALL ON TIMING OF ANY OVERNIGHT CONVECTION AS THE SHORT TERM
MODELS HAVE BEEN HAVING QUITE A BIT OF DIFFICULTY
TRACKING/PREDICTING STORM INITIATION/EVOLUTION TODAY SO FAR.
SURFACE ANALYSIS SHOWS A COLD FRONT PROGRESSING ACROSS IOWA THIS
EVENING. HOWEVER...THE NEAREST UPPER SUPPORT TO HELP WITH ANY
UPDRAFTS THAT ARE TRIGGERED BY THE FRONT ARE WELL TO THE WEST IN
NEBRASKA/KANSAS AND WESTERN MISSOURI...WHERE A SEVERE STORM WATCH
IS IN EFFECT. WE EXPECT THE LOW LEVEL NOCTURNAL JET TO INCREASE
AFTER SUNSET...AND AID IN STORM SUPPORT AS A COMPLEX TRIES TO GET
ORGANIZED TOWARD MIDNIGHT ACROSS NORTHERN MISSOURI.
THE LATEST IR SATELLITE PIX ARE SHOWING THAT CONVECTION IS FINALLY
DEVELOPING IN NORTHWESTERN MISSOURI. THE 23Z HRRR OUTPUT PREDICTS
ONE COMPLEX OF STORMS WILL RIDE NORTHEAST FROM IOWA INTO NORTHERN
IL...AND ANOTHER COMPLEX IN MISSOURI WILL CURL TO THE SOUTHEAST
CLIPPING SOUTHERN IL...WITH A WEAKER STORM COMPLEX BETWEEN THE TWO
DRIFTING ACROSS CENTRAL IL ALONG THE COLD FRONT.
WE HAVE PLENTY OF INSTABILITY AVAILABLE FOR STORMS ACROSS C
IL...WITH 2000-3000 J/KG MLCAPE. SO STORMS SHOULD DEVELOP...BUT
COVERAGE WILL BE MORE SCATTERED. VERY HEAVY RAINFALL WILL BE
POSSIBLE. PWATS ARE AROUND 2.0 TO 2.2 INCHES.
WE LOWERED POPS THIS EVENING TO SLIGHT CHANCE...AND LOWERED THE
CHANCE POPS AFTER MIDNIGHT INTO THE 30-40 PCT RANGE INSTEAD OF
AROUND 50 PCT.
UPDATES WERE ALSO NEEDED TO SKY GRIDS. THE REMAINING GRIDS WERE
GENERALLY ON TRACK. UPDATED FORECAST INFO WILL BE AVAILABLE SHORTLY.
SHIMON
&&
.AVIATION...
ISSUED 1145 PM CDT TUE JUL 9 2013
DELAYED ONSET OF STORMS CONTINUES...AND THE 02Z HRRR CONTINUES TO
SHOW STORMS HOLDING OFF UNTIL AFTER 11Z-12Z FOR PIA...WITH A LINE
OF STORMS FROM SPI TO CMI IN PLACE AROUND 16Z-17Z. WE PUSHED THE
START OF ANY VCTS LATER IN THE TAF PERIOD TO MATCH THAT
PROGRESSION. STILL...THE STORMS WILL BE OF A SCATTERED
COVERAGE...SO ANY SHORT PERIOD IFR/LIFR DURING ANY THUNDERSTORMS
WAS LEFT OUT. EVEN MVFR WILL BE LIMITED TO ANY STORM PATHS ACROSS
THE AIRPORTS.
WE WILL CONTINUE THE VFR PREVAILING...UNTIL ANY STORMS DEVELOP
LATE TONIGHT OR WED MORNING. WINDS WILL START OUR
SOUTHWESTERLY...THEN VEER TO THE NW AFTER FROPA. BY WED
AFTERNOON...TURBULENT MIXING WILL PUSH SUSTAINED WINDS IN THE
10-15KT RANGE. WINDS WILL SUBSIDE BY SUNSET...BUT REMAIN NORTH
THROUGH 06Z WED NIGHT.
SHIMON
&&
.PREV 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 COINCIDENT 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 RE-FIRE AHEAD OF THE FRONT TOMORROW AFTN. IF WE SEE
VERY LITTLE ACTIVITY TONIGHT...CHANCES ARE WE WILL SEE STORMS RE-FIRE
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
TEMPERATURES RISING BACK INTO THE UPPER 80S TO AROUND 90 BY SUNDAY
AND MONDAY.
SMITH
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
140 AM EDT WED JUL 10 2013
.SYNOPSIS...
ISSUED AT 130 AM EDT TUE JUL 9 2013
A SEASONABLY STRONG COLD FRONT WILL MOVE THROUGH THE GREAT LAKES
REGION TODAY. THIS FRONT WILL BRING A CHANCE FOR THUNDERSTORMS AND
LOCALLY HEAVY RAIN TO MUCH OF THE AREA TODAY. THE DAY WILL START
WARM AND MUGGY. HIGH PRESSURE WILL FOLLOW TONIGHT WITH COOLER AND
RELATIVELY DRIER AIR MAKING IT FEEL MUCH MORE COMFORTABLE.
&&
.UPDATE...
ISSUED AT 651 PM EDT TUE JUL 9 2013
CONVECTION EARLIER THIS AFTERNOON HAS HELPED STABILIZE THE NORTHERN
HALF OF OUR CWA...WHILE MLCAPES STILL HOVER AROUND 2000 J/KG IN OUR
EXTREME SOUTH. A FEW STRONG STORMS REMAIN POSSIBLE IN THIS AREA BUT
FORCING IS WEAK AND DEEP LAYER SHEAR IS ONLY AROUND 20 KTS SO
CONVECTION WILL REMAIN ISOLATED AND PULSEY THROUGH THE REST OF THE
EVENING. LATEST WATER VAPOR LOOP AND MSAS ANALYSIS SHOW MAIN
MIDLEVEL HEIGHT FALLS AND ASSOCIATED COLD FRONT REMAIN WELL
NORTHWEST OF HERE. THERE IS ALSO A WEAK AREA OF SUBSIDENCE AND SOME
MIDLEVEL DRY AIR AHEAD OF THIS COLD FRONT THAT IS HELPING TO
SUPPRESS CONVECTION ACROSS IOWA DESPITE DECENT INSTABILITY. A FEW
STORMS HAVE FIRED ACROSS WISCONSIN BUT THE PROSPECTS FOR AN
ORGANIZED MCS TO DEVELOP AND PROPAGATE INTO OUR AREA AS SUGGESTED BY
SOME EARLIER HI-RES RUNS APPEAR TO BE DWINDLING. LLJ WILL BEGIN TO
RAMP UP LATER TONIGHT THOUGH AND THIS ENHANCED CONVERGENCE AHEAD OF
THE APPROACHING COLD FRONT WILL HELP SUPPORT SOME PRECIP LATER
TONIGHT WITH ABOUT 1000 J/KG OF ELEVATED INSTABILITY. WILL TAKE SOME
TIME FOR THIS ACTIVITY TO REACH OUR CWA...PROBABLY AFTER
MIDNIGHT...AND THE LATEST HRRR KEEPS CONVECTION FAIRLY SCATTERED.
GIVEN POOR MIDLEVEL LAPSE RATES...WEAK FORCING...AND LACK OF
CONVECTION/STABLE CONDITIONS IMMEDIATELY UPSTREAM WILL BE ADDING
SOME DETAIL TO THE POP GRIDS FOR THIS EVENING AND SCALING BACK TO
SCT/CHANCE WORDING FOR THE ENTIRE OVERNIGHT PERIOD. WIDESPREAD
SEVERE WEATHER NOT EXPECTED DUE TO ELEVATED NATURE OF
STORMS...MARGINAL MUCAPE VALUES...AND WEAK SHEAR. WILL LEAVE THE
FLASH FLOOD WATCH UP THOUGH AS ANY SUSTAINED UPDRAFTS/TRAINING
STORMS COULD PRODUCE A LOCALIZED FLOODING THREAT WITH SUCH A MOIST
AIRMASS IN PLACE...PWATS STILL HOVERING AROUND 2 INCHES. UPDATED
ZFP WILL BE OUT SOON.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 449 PM EDT TUE JUL 9 2013
THUNDERSTORMS WERE CONTINUING TO DEVELOP IN A VERY UNSTABLE
AIRMASS AHEAD OF AN APPROACHING UPPER LEVEL TROF AND COLD FRONT.
SPC MESO ANALYSIS SHOWS PRECIP WATER VALUES EXCEEDING 2.2 INCHES
OVER NRN INDIANA. HOWEVER...MID LEVEL LAPSE RATES OF 5.5 C/KM WERE
REALLY LIMITING CONVECTIVE EXTENT UPSTREAM AND MAY BE A
SIGNIFICANT FACTOR TONIGHT IN THE DEVELOPMENT OF MORE CONVECTION.
FOR THIS PACKAGE... FAVORED MAINLY THE HIGH RES WPC
MODELS...ESPECIALLY 4KM NAM. HAVE ADDED A FLASH FLOOD WATCH OVER
NW OHIO WHERE 3 HOUR FLASH FLOOD GUIDANCE WAS DOWN TO ABOUT 1.0
INCH OVER SOME COUNTIES WHERE RECENT RAINFALL OF SEVERAL INCHES
HAS OCCURRED. IT LOOKS TO BE HARD FOR STORMS TO PRODUCE SEVERE
WEATHER LATER TODAY OR TONIGHT GIVEN A VERY HIGH WET BULB ZERO
OVER 13K AND LOW BULK SHEAR WITH STABLE MID LEVEL LAPSE RATES.
CURRENT THINKING WIND GUSTS SHOULD TOP OUT AROUND 40 MPH. SOME
LINGERING STORMS ARE POSSIBLE WEDNESDAY...BUT GIVEN OVERNIGHT
CONVECTION... LOW LEVEL CONDITIONS SHOULD BECOME TOO STABLE TO
SUPPORT SEVERE STORMS.
&&
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 449 PM EDT TUE JUL 9 2013
SHRTWV MOVG INTO THE NRN PLAINS THIS AFTN EXPECTED TO BE LOCATED
OVER THE GRTLKS/OH VALLEY WED EVE. ACCOMPANYING SFC CDFNT SHOULD BE
JUST SE OF SERN PORTION OF CWA. A SLIGHT CHC OF SHOWERS/TSTMS
LINGERING INTO WED EVE WAS MAINTAINED OVER EXTREME SE.
CAA/SUBSIDENCE BEHIND THIS SYSTEM WILL RESULT IN DIMINISHING CLOUD
COVER WITH COOLER AND LESS HUMID CONDITIONS WED NIGHT AND THU.
FAIR WX WILL CONT THU NGT-FRI AS SFC HIGH MOVES SLOWLY EAST ACROSS
THE GRTLKS. WK WAA EXPECTED OVER THE WEEKEND AS GRTLKS HIGH MOVES
EAST ACROSS NEW ENGLAND AND MERGES WITH STRONG WRN ATLANTIC
ANTICYCLONE. THIS ALONG WITH UPR LEVEL RIDGE EXPANDING NEWD FROM THE
SRN ROCKIES/PLAINS TOWARD THE GRTLKS SHOULD RESULT IN A WARMING
TREND AND DRY CONDITIONS THROUGH THE WEEKEND AND INTO EARLY NEXT
WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 131 AM EDT WED JUL 10 2013
SUBSIDENCE AND DRIER MID LEVEL AIR BEHIND EARLIER SHORT WAVE HAS
KEPT TSRA FROM DEVELOPING SO FAR. 00Z ILX SOUNDING SHOWED A DECENT
CAP AND THE MID LEVEL DRY AIR. WATER VAPOR SHOWS SHORT WAVE OVER
NORTHERN PLAINS DIVING SOUTHEAST AND BEGINNING TO CATCH SURFACE
COLD FRONT. MESOANALYSIS SHOWING UNSTABLE ATMOSPHERE IN PLACE WITH
PLENTY OF MOISTURE TO FUEL TSRA. HI RES GUIDANCE SPLIT ON
DEVELOPMENT OVERNIGHT BUT MOST MODELS DO SHOW AT LEAST SOME
SCATTERED CONVECTION ALONG FRONT AS IT MOVES THROUGH. THUS KEPT
PREVIOUS TEMPO TSRA GROUPS AT TAF SITES BUT MOVED TIMING BACK BY 2
TO 4 HOURS TO COINCIDE WITH FROPA. MAY NEED A FEW MORE HOURS OF
TSRA AT KFWA BUT PREFER TO HOLD OFF AND MONITOR DEVELOPMENT BEFORE
EXPANDING CHANCES GIVEN CAP. HIGH PRESSURE MOVES IN FOR AFTERNOON
AND TONIGHT WITH AN EXTENDED PERIOD OF DRY WEATHER EXPECTED INTO
THE WEEKEND.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...FLASH FLOOD WATCH UNTIL NOON EDT TODAY FOR OHZ001-002-004-005-
015-016-024-025.
LM...NONE.
&&
$$
UPDATE...AGD
SYNOPSIS...SKIPPER
SHORT TERM...SKIPPER
LONG TERM...JT
AVIATION...LASHLEY
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AREA FORECAST DISCUSSION
NWS WICHITA KS
832 PM CDT THU JUL 11 2013
.UPDATE...
ISSUED AT 831 PM CDT THU JUL 11 2013
OUTFLOW BOUNDARIES FROM EARLY AFTERNOON CONVECTION IN SE KS PUSHED
WELL INTO OK THIS EVENING...KEEPING ANY CONVECTIVE ACTIVITY WELL TO
THE SOUTH OF THE AREA. LATEST RUC DOES SHOW AN UNSTABLE AIRMASS
STILL ACROSS SOUTH CEN KS...BUT EML HAS CONTINUED TO WARM LEADING TO
LITTLE IF ANY CU DEVELOPMENT ACROSS SRN KS. EXPECTING WARMER TEMPS
ALOFT TO CONTINUE ACROSS THE FORECAST AREA LATE THIS EVENING AND
OVERNIGHT WHICH WILL KEEP THINGS MOSTLY CLEAR. SO WILL REMOVE
CONVECTIVE CHANCES OVER EXTREME SRN KS AND KEEP THINGS DRY
OVERNIGHT.
KETCHAM
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 246 PM CDT THU JUL 11 2013
RESIDUAL SHOWERS/STORMS WILL CONTINUE TO DRIFT SOUTHEAST THIS
AFTERNOON AND EVENING FROM MCV ALOFT...BUT SHOULD DECREASE RAPIDLY
JUST AFTER SUNSET. OTHERWISE THE HEAT AND HUMIDITY WILL BUILD BACK
OVER THE REGION FOR FRIDAY AND SATURDAY...AS THE UPPER LEVEL RIDGE
CENTER POSITIONS ITSELF OVER THE CENTRAL PLAINS. HEADING INTO SUNDAY
MODEL SOLUTIONS FOR THE PAST TWO CYCLES CONTINUE TO SHOW CURRENT
UPPER WAVE OVER THE GREAT LAKES CUTTING OFF THEN RETRO-GRADING
WESTWARD INTO KANSAS THIS PERIOD. WE WILL INTRODUCE SOME
PRECIPITATION CHANCES FOR SUNDAY AND LOWER DAYTIME TEMPERATURES A
BIT.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 246 PM CDT THU JUL 11 2013
THE UPPER LOW WILL KEEP THINGS UNSETTLED FOR MONDAY/TUESDAY WITH
SCATTERED SHOWERS AND STORMS POSSIBLE...WITH THE COVERAGE MORE
WIDESPREAD DURING THE AFTERNOON/EVENING HOURS DUE TO DAYTIME
HEATING. DAYTIME HIGHS WILL BE AROUND OR SLIGHTLY BELOW NORMAL FOR
EARLY NEXT WEEK. MEANWHILE THE UPPER LEVEL RIDGE CENTER WILL BUILD
BACK OVER THE CENTRAL PLAINS FOR MID TO LATE WEEK.
JAKUB
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 627 PM CDT THU JUL 11 2013
VFR CONDITIONS WILL CONTINUE ACROSS THE AREA...FOR THE NEXT 24
HOURS. MCV THAT LED TO EARLIER SHOWERS OVER SE KS HAS DROPPED
SOUTHEAST OF THE AREA...SO SUBSIDENCE IN ITS WAKE WILL LEAD TO CLEAR
SKIES TONIGHT. WILL ALSO SEE CLEAR SKIES ACROSS THE REST OF THE AREA
MID LEVEL TEMPS WARM KEEPING ANY CLOUDS FROM FORMING.
KETCHAM
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 72 98 75 98 / 10 0 0 0
HUTCHINSON 72 100 76 100 / 10 0 0 0
NEWTON 71 98 75 98 / 10 0 0 0
ELDORADO 71 97 74 97 / 10 0 0 0
WINFIELD-KWLD 73 98 75 98 / 20 0 0 0
RUSSELL 72 103 76 102 / 10 0 0 0
GREAT BEND 73 103 76 102 / 10 0 0 0
SALINA 72 99 76 101 / 10 0 0 0
MCPHERSON 72 99 76 100 / 10 0 0 0
COFFEYVILLE 71 96 72 95 / 10 0 0 0
CHANUTE 69 96 70 94 / 10 0 0 0
IOLA 68 96 70 94 / 0 0 0 0
PARSONS-KPPF 70 96 71 95 / 10 0 0 0
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1209 PM CDT WED JUL 10 2013
...UPDATED SYNOPSIS AND AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 1206 PM CDT WED JUL 10 2013
AT 12Z WEDNESDAY A 500MB HIGH WAS LOCATED NEAR THE FOUR CORNERS
AREA WITH SEVERAL THERMAL TROUGHS LOCATED AROUND THIS HIGH. ONE
APPEARS TO BE LOCATED IN NORTHWEST COLORADO AND ANOTHER IN NEVADA.
AT THE 700MB LEVEL TEMPERATURES ACROSS THE CENTRAL PLAINS VARIED
FROM 11C AT NORTH PLATTE TO 13C AT DODGE CITY TO 14C AT DENVER. A
WEDGE OF HIGHER DEWPOINTS WERE OBSERVED FROM THE PANHANDLE OF
TEXAS, ACROSS EASTERN COLORADO INTO SOUTHWEST SOUTH DAKOTA. A
850MB FRONT APPEARS TO BE LOCATED FROM SOUTHEAST WYOMING ACROSS
NORTHERN KANSAS INTO NORTHERN MISSOURI WITH +24C REPORTED SOUTH
OF THIS FRONT AT DODGE CITY AND TOPEKA. A SURFACE COLD FRONT WAS
LOCATED FROM SOUTHEAST COLORADO INTO WESTERN OKLAHOMA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 314 AM CDT WED JUL 10 2013
THE FORECAST FOR TODAY AND TONIGHT WILL BE CHALLENGING WITH REGARDS
TO PLACEMENT, TIMING, AND INTENSITY OF THUNDERSTORMS. THE COLD FRONT
WILL STALL OUT AND DISSOLVE AS IT APPROACHES THE OKLAHOMA BORDER
TODAY. WINDS NORTH OF THE FRONT WILL BECOME EAST AND EVENTUALLY
SOUTHEAST...ESPECIALLY ALONG THE COLORADO BORDER. A RICH SOURCE OF
LOW LEVEL MOISTURE WILL BE IN PLACE NORTH OF THE FRONT WITH SURFACE
DEWPOINTS IN THE MID TO UPPER 60S ACROSS PORTIONS OF CENTRAL AND
WESTERN KANSAS. DESPITE THE PASSAGE OF THE COLD FRONT AND BEING ON
THE NORTH SIDE OF THE BOUNDARY...AFTERNOON TEMPERATURES WILL STILL
REACH THE 95 TO 98F RANGE ACROSS MUCH OF THE SOUTHWEST KANSAS REGION
WITH STILL FAIRLY HIGH LOW LEVEL THICKNESSES. LOWER TROPOSPHERIC
CONVERGENCE ALONG THE OLD FRONTAL ZONE ACROSS FAR SOUTHWEST KANSAS
NEAR THE OKLAHOMA BORDER WILL AID IN FORMATION OF AFTERNOON
THUNDERSTORMS. THERE WILL BE A GREATER AMOUNT OF SBCAPE TODAY WITH
MUCH HIGHER DEWPOINT VALUES/MOISTURE CONTENT OVER YESTERDAY. THIS
WOULD ARGUE FOR MORE ORGANIZED CONVECTION. ONE OR MORE MESOSCALE
CONVECTIVE SYSTEMS (MCS) MAY DEVELOP FROM SOUTHWEST KANSAS
NORTH-NORTHWESTWARD TO THE CHEYENNE RIDGE AREA. THE GREATER RISK FOR
SEVERE STORMS WILL BE FARTHER NORTH (MOSTLY NORTH OF THE DDC
FORECAST AREA) WHERE DEEP LAYER SHEAR WILL SUPPORT MORE ORGANIZED
MULTI-CELL CLUSTERS AND PERHAPS A SUPERCELL OR TWO. WILL KEEP POPS
IN THE 30 TO 40 PERCENT TERRITORY GIVEN THE UNCERTAINTY OF PLACEMENT
AND COVERAGE OF THUNDERSTORM CLUSTERS/EVENTUAL MCS...HOWEVER POPS
MAY NEED TO BE INCREASED FOR SOME SECTIONS OF THE FORECAST AREA AS
SHORT TERM HIGHER RESOLUTION MODELS LIKE THE HRRR GET A BETTER
HANDLE ON THE ENVIRONMENT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 400 AM CDT WED JUL 10 2013
THE EXTENDED PERIOD IS DRY AND HOT. ON THURSDAY, LEE TROUGHING AND WARM
AIR ADVECTION ALONG WITH 850 HPA TEMPS IN THE 20S DEG C WILL SUPPORT
MAXIMUMS IN THE MID TO UPPER 90S DEG F. NO PRECIPITATION IS EXPECTED.
ON FRIDAY, THE 850 HPA WARM PLUME WILL SPREAD FARTHER NORTH AND EAST
WITH 850 HPA TEMPERATURES FLIRTING WITH 30 DEG C. THIS SUPPORTS MIX
DOWN TEMPERATURES IN THE LOW 100S DEG F FRIDAY AND SATURDAY. MINIMUMS
WILL BE IN THE 70S DEG F THROUGH THIS PERIOD. ON SUNDAY, A JET STREAK
MOVING ACROSS THE NORTHERN PLAINS INTO THE CENTRAL CANADIAN PRAIRIE
PROVINCES WILL USHER IN THE PASSAGE OF A COLD FRONT ACROSS NEBRASKA
AND WILL STALL OUT ACROSS THE CORNHUSKER STATE. THIS COULD KNOCK DOWN
TEMPERATURES LOCALLY A FEW DEGREES. BOTH THE GFS AND ECMWF SHOW CONVECTION
ASSOCIATED WITH THE FRONT AND ANY POST FRONTAL/OROGRAPHIC CONVECTION
REMAINING WELL WEST/NORTHWEST OF THE AREA. AS RESULT, WENT WITH AOB
14 PERCENT PRECIPITATION PROBABILITY PERCENTAGE POINTS. THEREAFTER,
THE RIDGE WILL CONTINUE TO DOMINATE WITH DRY AND HOT CONDITIONS PREVAILING.
THERE COULD BE RETROGRESSION OF A SUBTROPICAL LOW NEXT WEEK, BUT THIS
WILL NOT HAVE ANY SIGNIFICANT IMPACTS TO SW KANSAS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1206 PM CDT WED JUL 10 2013
A SURFACE FRONT WILL EXTEND FROM SOUTHEAST COLORADO INTO WESTERN
OKLAHOMA. NORTH OF THIS FRONT AN EASTERLY WIND WILL CONTINUE AT 10
TO 15KTS ACROSS SOUTHWEST KANSAS THROUGH 00Z THURSDAY. THESE
EASTERLY WINDS WILL THEN BEGIN TO GRADUALLY VEER TO THE SOUTHEAST
EARLY TONIGHT. CONVECTION IS EXPECTED TO DEVELOP ACROSS EASTERN
COLORADO LATER THIS AFTERNOON AND THEN SPREAD EAST/SOUTHEAST
ACROSS WESTERN KANSAS OVERNIGHT. LATEST MODELS SUGGEST THE BETTER
OPPORTUNITY FOR CONVECTION AT GCK AND DDC WILL BE BETWEEN 00Z AND
06Z AND AT HYS BETWEEN 03Z AND 09Z. BASED ON LATEST BUFR SOUNDINGS
THE CLOUD BASES WILL BE ABOVE 5000FT SO VFR CONDITIONS ARE
EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 96 70 97 73 / 30 40 10 0
GCK 94 69 98 73 / 30 40 0 0
EHA 95 69 98 72 / 30 30 0 10
LBL 97 70 99 72 / 30 30 0 0
HYS 93 69 95 73 / 20 30 20 0
P28 99 72 98 73 / 20 30 20 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...UMSCHEID
LONG TERM...SUGDEN
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
601 AM CDT WED JUL 10 2013
...UPDATE TO AVIATION FOR 12 COORDINATED UNIVERSAL TIME TAFS...
.SYNOPSIS...
ISSUED AT 314 AM CDT WED JUL 10 2013
A FAIRLY INTENSE SHORTWAVE TROUGH MOVED ACROSS THE NORTHERN PLAINS
INTO THE UPPER MIDWEST REGION TUESDAY EVENING. THERE WAS A 70-80
KNOT 250MB JET STREAK ASSOCIATED WITH THIS STORM SYSTEM CENTERED
ACROSS EASTERN SOUTH DAKOTA PER 10.00Z RAOB AND RAP ANALYSIS. THE
COLD FRONT TIED TO THIS STORM SYSTEM PUSHED INTO NORTHERN KANSAS AND
BY 08Z EXTENDED FROM EAST CENTRAL COLORADO TO NORTH CENTRAL KANSAS.
THE THUNDERSTORM ACTIVITY THAT MOVED ACROSS PORTIONS OF SOUTHWEST
AND SOUTH CENTRAL KANSAS YESTERDAY EVENING CONTINUED TO MOVE SLOWLY
SOUTHEAST INTO NORTHERN OKLAHOMA. ANOTHER SMALL CLUSTER OF STRONG
THUNDERSTORMS DEVELOPED ACROSS FAR NORTHWEST KANSAS ADJACENT THE
SOUTHWEST NEBRASKA BORDER...WHICH WAS ALSO MOVING SOUTHEAST TOWARD
THE INTERSTATE 70 CORRIDOR.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 314 AM CDT WED JUL 10 2013
THE FORECAST FOR TODAY AND TONIGHT WILL BE CHALLENGING WITH REGARDS
TO PLACEMENT, TIMING, AND INTENSITY OF THUNDERSTORMS. THE COLD FRONT
WILL STALL OUT AND DISSOLVE AS IT APPROACHES THE OKLAHOMA BORDER
TODAY. WINDS NORTH OF THE FRONT WILL BECOME EAST AND EVENTUALLY
SOUTHEAST...ESPECIALLY ALONG THE COLORADO BORDER. A RICH SOURCE OF
LOW LEVEL MOISTURE WILL BE IN PLACE NORTH OF THE FRONT WITH SURFACE
DEWPOINTS IN THE MID TO UPPER 60S ACROSS PORTIONS OF CENTRAL AND
WESTERN KANSAS. DESPITE THE PASSAGE OF THE COLD FRONT AND BEING ON
THE NORTH SIDE OF THE BOUNDARY...AFTERNOON TEMPERATURES WILL STILL
REACH THE 95 TO 98F RANGE ACROSS MUCH OF THE SOUTHWEST KANSAS REGION
WITH STILL FAIRLY HIGH LOW LEVEL THICKNESSES. LOWER TROPOSPHERIC
CONVERGENCE ALONG THE OLD FRONTAL ZONE ACROSS FAR SOUTHWEST KANSAS
NEAR THE OKLAHOMA BORDER WILL AID IN FORMATION OF AFTERNOON
THUNDERSTORMS. THERE WILL BE A GREATER AMOUNT OF SBCAPE TODAY WITH
MUCH HIGHER DEWPOINT VALUES/MOISTURE CONTENT OVER YESTERDAY. THIS
WOULD ARGUE FOR MORE ORGANIZED CONVECTION. ONE OR MORE MESOSCALE
CONVECTIVE SYSTEMS (MCS) MAY DEVELOP FROM SOUTHWEST KANSAS
NORTH-NORTHWESTWARD TO THE CHEYENNE RIDGE AREA. THE GREATER RISK FOR
SEVERE STORMS WILL BE FARTHER NORTH (MOSTLY NORTH OF THE DDC
FORECAST AREA) WHERE DEEP LAYER SHEAR WILL SUPPORT MORE ORGANIZED
MULTI-CELL CLUSTERS AND PERHAPS A SUPERCELL OR TWO. WILL KEEP POPS
IN THE 30 TO 40 PERCENT TERRITORY GIVEN THE UNCERTAINTY OF PLACEMENT
AND COVERAGE OF THUNDERSTORM CLUSTERS/EVENTUAL MCS...HOWEVER POPS
MAY NEED TO BE INCREASED FOR SOME SECTIONS OF THE FORECAST AREA AS
SHORT TERM HIGHER RESOLUTION MODELS LIKE THE HRRR GET A BETTER
HANDLE ON THE ENVIRONMENT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 400 AM CDT WED JUL 10 2013
THE EXTENDED PERIOD IS DRY AND HOT. ON THURSDAY, LEE TROUGHING AND WARM
AIR ADVECTION ALONG WITH 850 HPA TEMPS IN THE 20S DEG C WILL SUPPORT
MAXIMUMS IN THE MID TO UPPER 90S DEG F. NO PRECIPITATION IS EXPECTED.
ON FRIDAY, THE 850 HPA WARM PLUME WILL SPREAD FARTHER NORTH AND EAST
WITH 850 HPA TEMPERATURES FLIRTING WITH 30 DEG C. THIS SUPPORTS MIX
DOWN TEMPERATURES IN THE LOW 100S DEG F FRIDAY AND SATURDAY. MINIMUMS
WILL BE IN THE 70S DEG F THROUGH THIS PERIOD. ON SUNDAY, A JET STREAK
MOVING ACROSS THE NORTHERN PLAINS INTO THE CENTRAL CANADIAN PRAIRIE
PROVINCES WILL USHER IN THE PASSAGE OF A COLD FRONT ACROSS NEBRASKA
AND WILL STALL OUT ACROSS THE CORNHUSKER STATE. THIS COULD KNOCK DOWN
TEMPERATURES LOCALLY A FEW DEGREES. BOTH THE GFS AND ECMWF SHOW CONVECTION
ASSOCIATED WITH THE FRONT AND ANY POST FRONTAL/OROGRAPHIC CONVECTION
REMAINING WELL WEST/NORTHWEST OF THE AREA. AS RESULT, WENT WITH AOB
14 PERCENT PRECIPITATION PROBABILITY PERCENTAGE POINTS. THEREAFTER,
THE RIDGE WILL CONTINUE TO DOMINATE WITH DRY AND HOT CONDITIONS PREVAILING.
THERE COULD BE RETROGRESSION OF A SUBTROPICAL LOW NEXT WEEK, BUT THIS
WILL NOT HAVE ANY SIGNIFICANT IMPACTS TO SW KANSAS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 600 AM CDT WED JUL 10 2013
SHOWERS AND THUNDERSTORMS WILL BE LIKELY AGAIN THIS AFTERNOON AND EVENING.
CLOUDS BASES EXPECTED TO BE FAIRLY HIGH, SO VFR CIGS SHOULD PREVAIL.
WINDS WILL BE UPSLOPE/EASTERLY 10-20 KT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 96 70 97 73 / 30 40 10 0
GCK 94 69 98 73 / 30 40 0 0
EHA 95 69 98 72 / 30 30 0 10
LBL 97 70 99 72 / 30 30 0 0
HYS 93 69 95 73 / 20 30 20 0
P28 99 72 98 73 / 20 30 20 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...UMSCHEID
SHORT TERM...UMSCHEID
LONG TERM...SUGDEN
AVIATION...SUGDEN
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
400 AM CDT WED JUL 10 2013
...UPDATE TO LONG TERM DISCUSSION...
.SYNOPSIS...
ISSUED AT 314 AM CDT WED JUL 10 2013
A FAIRLY INTENSE SHORTWAVE TROUGH MOVED ACROSS THE NORTHERN PLAINS
INTO THE UPPER MIDWEST REGION TUESDAY EVENING. THERE WAS A 70-80
KNOT 250MB JET STREAK ASSOCIATED WITH THIS STORM SYSTEM CENTERED
ACROSS EASTERN SOUTH DAKOTA PER 10.00Z RAOB AND RAP ANALYSIS. THE
COLD FRONT TIED TO THIS STORM SYSTEM PUSHED INTO NORTHERN KANSAS AND
BY 08Z EXTENDED FROM EAST CENTRAL COLORADO TO NORTH CENTRAL KANSAS.
THE THUNDERSTORM ACTIVITY THAT MOVED ACROSS PORTIONS OF SOUTHWEST
AND SOUTH CENTRAL KANSAS YESTERDAY EVENING CONTINUED TO MOVE SLOWLY
SOUTHEAST INTO NORTHERN OKLAHOMA. ANOTHER SMALL CLUSTER OF STRONG
THUNDERSTORMS DEVELOPED ACROSS FAR NORTHWEST KANSAS ADJACENT THE
SOUTHWEST NEBRASKA BORDER...WHICH WAS ALSO MOVING SOUTHEAST TOWARD
THE INTERSTATE 70 CORRIDOR.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 314 AM CDT WED JUL 10 2013
THE FORECAST FOR TODAY AND TONIGHT WILL BE CHALLENGING WITH REGARDS
TO PLACEMENT, TIMING, AND INTENSITY OF THUNDERSTORMS. THE COLD FRONT
WILL STALL OUT AND DISSOLVE AS IT APPROACHES THE OKLAHOMA BORDER
TODAY. WINDS NORTH OF THE FRONT WILL BECOME EAST AND EVENTUALLY
SOUTHEAST...ESPECIALLY ALONG THE COLORADO BORDER. A RICH SOURCE OF
LOW LEVEL MOISTURE WILL BE IN PLACE NORTH OF THE FRONT WITH SURFACE
DEWPOINTS IN THE MID TO UPPER 60S ACROSS PORTIONS OF CENTRAL AND
WESTERN KANSAS. DESPITE THE PASSAGE OF THE COLD FRONT AND BEING ON
THE NORTH SIDE OF THE BOUNDARY...AFTERNOON TEMPERATURES WILL STILL
REACH THE 95 TO 98F RANGE ACROSS MUCH OF THE SOUTHWEST KANSAS REGION
WITH STILL FAIRLY HIGH LOW LEVEL THICKNESSES. LOWER TROPOSPHERIC
CONVERGENCE ALONG THE OLD FRONTAL ZONE ACROSS FAR SOUTHWEST KANSAS
NEAR THE OKLAHOMA BORDER WILL AID IN FORMATION OF AFTERNOON
THUNDERSTORMS. THERE WILL BE A GREATER AMOUNT OF SBCAPE TODAY WITH
MUCH HIGHER DEWPOINT VALUES/MOISTURE CONTENT OVER YESTERDAY. THIS
WOULD ARGUE FOR MORE ORGANIZED CONVECTION. ONE OR MORE MESOSCALE
CONVECTIVE SYSTEMS (MCS) MAY DEVELOP FROM SOUTHWEST KANSAS
NORTH-NORTHWESTWARD TO THE CHEYENNE RIDGE AREA. THE GREATER RISK FOR
SEVERE STORMS WILL BE FARTHER NORTH (MOSTLY NORTH OF THE DDC
FORECAST AREA) WHERE DEEP LAYER SHEAR WILL SUPPORT MORE ORGANIZED
MULTI-CELL CLUSTERS AND PERHAPS A SUPERCELL OR TWO. WILL KEEP POPS
IN THE 30 TO 40 PERCENT TERRITORY GIVEN THE UNCERTAINTY OF PLACEMENT
AND COVERAGE OF THUNDERSTORM CLUSTERS/EVENTUAL MCS...HOWEVER POPS
MAY NEED TO BE INCREASED FOR SOME SECTIONS OF THE FORECAST AREA AS
SHORT TERM HIGHER RESOLUTION MODELS LIKE THE HRRR GET A BETTER
HANDLE ON THE ENVIRONMENT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 400 AM CDT WED JUL 10 2013
THE EXTENDED PERIOD IS DRY AND HOT. ON THURSDAY, LEE TROUGHING AND WARM
AIR ADVECTION ALONG WITH 850 HPA TEMPS IN THE 20S DEG C WILL SUPPORT
MAXIMUMS IN THE MID TO UPPER 90S DEG F. NO PRECIPITATION IS EXPECTED.
ON FRIDAY, THE 850 HPA WARM PLUME WILL SPREAD FARTHER NORTH AND EAST
WITH 850 HPA TEMPERATURES FLIRTING WITH 30 DEG C. THIS SUPPORTS MIX
DOWN TEMPERATURES IN THE LOW 100S DEG F FRIDAY AND SATURDAY. MINIMUMS
WILL BE IN THE 70S DEG F THROUGH THIS PERIOD. ON SUNDAY, A JET STREAK
MOVING ACROSS THE NORTHERN PLAINS INTO THE CENTRAL CANADIAN PRAIRIE
PROVINCES WILL USHER IN THE PASSAGE OF A COLD FRONT ACROSS NEBRASKA
AND WILL STALL OUT ACROSS THE CORNHUSKER STATE. THIS COULD KNOCK DOWN
TEMPERATURES LOCALLY A FEW DEGREES. BOTH THE GFS AND ECMWF SHOW CONVECTION
ASSOCIATED WITH THE FRONT AND ANY POST FRONTAL/OROGRAPHIC CONVECTION
REMAINING WELL WEST/NORTHWEST OF THE AREA. AS RESULT, WENT WITH AOB
14 PERCENT PRECIPITATION PROBABILITY PERCENTAGE POINTS. THEREAFTER,
THE RIDGE WILL CONTINUE TO DOMINATE WITH DRY AND HOT CONDITIONS PREVAILING.
THERE COULD BE RETROGRESSION OF A SUBTROPICAL LOW NEXT WEEK, BUT THIS
WILL NOT HAVE ANY SIGNIFICANT IMPACTS TO SW KANSAS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1255 AM CDT WED JUL 10 2013
A SLOW-MOVING COLD FRONT WILL CONTINUE ITS PUSH THROUGH SOUTHWEST
KANSAS OVERNIGHT. WINDS BEHIND THE FRONT WILL BECOME EAST TO
NORTHEAST. WINDS WILL SLOWLY BECOME EAST-SOUTHEASTERLY DURING THE
DAY WEDNESDAY. ANOTHER ROUND OF THUNDERSTORMS WILL LIKELY DEVELOP
ALONG AND JUST NORTH OF THE FRONT LATE IN THE AFTERNOON
POTENTIALLY AFFECTING DDC AND GCK TERMINALS...SO WILL INCLUDE A
PROB30 FOR THUNDER DURING THE LATE AFTERNOON TO EARLY EVENING
HOURS. OTHERWISE...VFR CONDITIONS WILL PREVAIL.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 96 70 97 73 / 30 40 10 0
GCK 94 69 98 73 / 30 40 0 0
EHA 95 69 98 72 / 30 30 0 10
LBL 97 70 99 72 / 30 30 0 0
HYS 93 69 95 73 / 20 30 20 0
P28 99 72 98 73 / 20 30 20 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...UMSCHEID
SHORT TERM...UMSCHEID
LONG TERM...SUGDEN
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
315 AM CDT WED JUL 10 2013
...UPDATED SYNOPSIS AND SHORT TERM SECTIONS...
.SYNOPSIS...
ISSUED AT 314 AM CDT WED JUL 10 2013
A FAIRLY INTENSE SHORTWAVE TROUGH MOVED ACROSS THE NORTHERN PLAINS
INTO THE UPPER MIDWEST REGION TUESDAY EVENING. THERE WAS A 70-80
KNOT 250MB JET STREAK ASSOCIATED WITH THIS STORM SYSTEM CENTERED
ACROSS EASTERN SOUTH DAKOTA PER 10.00Z RAOB AND RAP ANALYSIS. THE
COLD FRONT TIED TO THIS STORM SYSTEM PUSHED INTO NORTHERN KANSAS AND
BY 08Z EXTENDED FROM EAST CENTRAL COLORADO TO NORTH CENTRAL KANSAS.
THE THUNDERSTORM ACTIVITY THAT MOVED ACROSS PORTIONS OF SOUTHWEST
AND SOUTH CENTRAL KANSAS YESTERDAY EVENING CONTINUED TO MOVE SLOWLY
SOUTHEAST INTO NORTHERN OKLAHOMA. ANOTHER SMALL CLUSTER OF STRONG
THUNDERSTORMS DEVELOPED ACROSS FAR NORTHWEST KANSAS ADJACENT THE
SOUTHWEST NEBRASKA BORDER...WHICH WAS ALSO MOVING SOUTHEAST TOWARD
THE INTERSTATE 70 CORRIDOR.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 314 AM CDT WED JUL 10 2013
THE FORECAST FOR TODAY AND TONIGHT WILL BE CHALLENGING WITH REGARDS
TO PLACEMENT, TIMING, AND INTENSITY OF THUNDERSTORMS. THE COLD FRONT
WILL STALL OUT AND DISSOLVE AS IT APPROACHES THE OKLAHOMA BORDER
TODAY. WINDS NORTH OF THE FRONT WILL BECOME EAST AND EVENTUALLY
SOUTHEAST...ESPECIALLY ALONG THE COLORADO BORDER. A RICH SOURCE OF
LOW LEVEL MOISTURE WILL BE IN PLACE NORTH OF THE FRONT WITH SURFACE
DEWPOINTS IN THE MID TO UPPER 60S ACROSS PORTIONS OF CENTRAL AND
WESTERN KANSAS. DESPITE THE PASSAGE OF THE COLD FRONT AND BEING ON
THE NORTH SIDE OF THE BOUNDARY...AFTERNOON TEMPERATURES WILL STILL
REACH THE 95 TO 98F RANGE ACROSS MUCH OF THE SOUTHWEST KANSAS REGION
WITH STILL FAIRLY HIGH LOW LEVEL THICKNESSES. LOWER TROPOSPHERIC
CONVERGENCE ALONG THE OLD FRONTAL ZONE ACROSS FAR SOUTHWEST KANSAS
NEAR THE OKLAHOMA BORDER WILL AID IN FORMATION OF AFTERNOON
THUNDERSTORMS. THERE WILL BE A GREATER AMOUNT OF SBCAPE TODAY WITH
MUCH HIGHER DEWPOINT VALUES/MOISTURE CONTENT OVER YESTERDAY. THIS
WOULD ARGUE FOR MORE ORGANIZED CONVECTION. ONE OR MORE MESOSCALE
CONVECTIVE SYSTEMS (MCS) MAY DEVELOP FROM SOUTHWEST KANSAS
NORTH-NORTHWESTWARD TO THE CHEYENNE RIDGE AREA. THE GREATER RISK FOR
SEVERE STORMS WILL BE FARTHER NORTH (MOSTLY NORTH OF THE DDC
FORECAST AREA) WHERE DEEP LAYER SHEAR WILL SUPPORT MORE ORGANIZED
MULTI-CELL CLUSTERS AND PERHAPS A SUPERCELL OR TWO. WILL KEEP POPS
IN THE 30 TO 40 PERCENT TERRITORY GIVEN THE UNCERTAINTY OF PLACEMENT
AND COVERAGE OF THUNDERSTORM CLUSTERS/EVENTUAL MCS...HOWEVER POPS
MAY NEED TO BE INCREASED FOR SOME SECTIONS OF THE FORECAST AREA AS
SHORT TERM HIGHER RESOLUTION MODELS LIKE THE HRRR GET A BETTER
HANDLE ON THE ENVIRONMENT.
.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 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1255 AM CDT WED JUL 10 2013
A SLOW-MOVING COLD FRONT WILL CONTINUE ITS PUSH THROUGH SOUTHWEST
KANSAS OVERNIGHT. WINDS BEHIND THE FRONT WILL BECOME EAST TO
NORTHEAST. WINDS WILL SLOWLY BECOME EAST-SOUTHEASTERLY DURING THE
DAY WEDNESDAY. ANOTHER ROUND OF THUNDERSTORMS WILL LIKLEY DEVELOP
ALONG AND JUST NORTH OF THE FRONT LATE IN THE AFTERNOON
POTENTIALLY AFFECTING DDC AND GCK TERMINALS...SO WILL INCLUDE A
PROB30 FOR THUNDER DURING THE LATE AFTERNOON TO EARLY EVENING
HOURS. OTHERWISE...VFR CONDITIONS WILL PREVAIL.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 96 70 97 73 / 30 40 10 0
GCK 94 69 98 73 / 30 40 0 0
EHA 95 69 98 72 / 30 30 0 10
LBL 97 70 99 72 / 30 30 0 0
HYS 93 69 95 73 / 20 30 20 0
P28 99 72 98 73 / 20 30 20 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...UMSCHEID
SHORT TERM...UMSCHEID
LONG TERM...KRUSE
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1138 PM MDT TUE JUL 9 2013
.UPDATE...
ISSUED AT 623 PM MDT TUE JUL 9 2013
FORECAST HAS BEEN UPDATED FOR THE EXPIRATION OF THE HEAT ADVISORY
AND ISSUANCE OF SEVERE THUNDERSTORM WATCH 405. STORMS SHOULD
SLOWLY MOVE OUT OF THE FORECAST AREA THIS EVENING. RECENT RUNS OF
THE HRRR MODEL SUGGEST THAT STORMS CURRENTLY IN NORTHWEST NEBRASKA
MAY MOVE TO THE SOUTHEAST ALONG THE EDGE OF THE RIDGE OF HIGH
PRESSURE. THESE STORMS WOULD MOVE INTO SOUTHWEST NEBRASKA AND
PORTIONS OF NORTHWEST KANSAS LATE TONIGHT. CAN NOT RULE OUT THESE
STORMS CLIPPING NORTHEAST COLORADO AS WELL. WILL CONTINUE TO WATCH
THESE STORMS AS WELL AND UPDATE AS NEEDED.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 143 PM MDT TUE JUL 9 2013
A HEAT ADVISORY REMAINS IN EFFECT FOR A PORTION OF THE FORECAST
AREA THIS AFTERNOON AS AMBIENT TEMPERATURES AND HEAT INDEX VALUES
INCREASE INTO THE 103-107 DEGREE RANGE.
ISOLATED TO SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS
AFTERNOON AND EVENING IN THE UNSTABLE AND CONVERGENT NEAR SURFACE
REGION IN THE VICINITY OF A SURFACE TROUGH THAT EXTENDS FROM WEST
CENTRAL KANSAS THROUGH SOUTHEAST NEBRASKA. STORM DEVELOPMENT WILL
BE AIDED BY THE LIFT ASSOCIATED WITH THE TAIL END OF THE UPPER
TROUGH WILL CONTINUE TO MOVE EASTWARD OVER THE NORTHERN PLAINS THIS
EVENING. SOME STORMS MAY BECOME SEVERE WITH THE STRONGER STORMS
EXPECTED MAINLY ALONG THE SOUTHEAST BORDER OF THE FORECAST AREA.
THE COLD FRONT POISED NORTH OF THE FORECAST AREA WILL PUSH
SOUTHWARD OVERNIGHT TONIGHT AND DURING THE DAY ON WEDNESDAY.
HIGH TEMPERATURES WILL BE ABOUT 10 DEGREES COOLER ON WEDNESDAY
THAN ON TUESDAY...BUT ARE EXPECTED TO REACH MAINLY INTO THE LOWER
TO MID 90S. THE FRONTAL BOUNDARY ENDS UP OVER THE SOUTHERN AND
WESTERN SECTIONS OF THE FORECAST AREA LATE IN THE DAY ON WEDNESDAY
AS SURFACE HIGH PRESSURE MOVES INTO PLACE OVER THE PLAINS STATES.
SCATTERED THUNDERSTORMS...SOME BECOMING SEVERE...ARE EXPECTED TO
DEVELOP OVER THE HIGHER TERRAIN TO THE WEST ALONG THE FRONTAL
BOUNDARY ON WEDNESDAY AFTERNOON AND EVENING. STORMS WILL DECREASE
IN COVERAGE AND INTENSITY AS THEY MOVE ACROSS THE REMAINDER OF
THE FORECAST AREA DURING THE EVENING AND OVERNIGHT HOURS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 232 PM MDT TUE JUL 9 2013
WED NIGHT-FRIDAY...591 DM H5 RIDGE WILL BE MAIN SYNOPTIC SCALE
INFLUENCE ON THE CWA THROUGH THE PERIOD AS IT BEGINS TO BUILD INTO
THE AREA ON WED NIGHT BEFORE BECOMING CENTERED OVER THE CWA ON
THURSDAY. SHORT WAVE TROUGH NOTED ON PROJECTED DYNAMIC TROPOPAUSE
FIELDS WILL AID IN THE DEVELOPMENT OF AFTERNOON AND EVENING
THUNDERSTORMS AS LARGE SCALE EASTERLY FLOW WILL KEEP AXIS OF
INSTABILITY CENTERED OVER THE AREA. GIVEN EXPECTED FLOW
PATTERN...STORMS SHOULD DRIFT TO THE SOUTHEAST INTO INCREASING
INSTABILITY AND THINK POTENTIAL FOR PRECIPITATION EXISTS ACROSS THE
ENTIRE CWA. FAIRLY CONFIDENT THAT STORMS WILL DEVELOP...BUT WITH
MODELS VARYING GREATLY BETWEEN EARLY AFTERNOON INITIATION/ENDING AND
PRECIPITATION MAINLY OCCURRING IN THE EVENING CONFIDENCE IN TIMING
TOO LOW TO GO ABOVE THE CHANCE RANGE. GIVEN EXPECTED THERMAL AND
WIND FIELDS...STRONG WAA MAY ALLOW STORMS TO LINGER THROUGH THE
NIGHT ESPECIALLY IN THE EASTERN CWA. PRECIPITATION CHANCES WILL
DIMINISH THROUGH THE REST OF THE PERIOD AS LARGE SCALE RIDGE MOVES
OVER THE AREA BRINGING WIDESPREAD SUBSIDENCE AND INCREASED CINH. A
STORM OR TWO IS POSSIBLE...BUT THINK COVERAGE WILL BE VERY LIMITED.
FOR TEMPS...POTENTIAL FOR OUTFLOW FROM WED NIGHT CONVECTION LOWERS
CONFIDENCE IN TEMP FORECAST ALTHOUGH GIVEN MODEL BIASES THE PAST 2
WEEKS NOT SURE IF I WANT TO GO AS COOL AS OPERATIONAL DATA SUGGESTS.
ANY POSSIBLE COOL DOWN WILL BE SHORT LIVED AS TEMPERATURES REBOUND
INTO THE LOW 100S BY FRIDAY.
IN THE EXTENDED (FRI NIGHT-TUESDAY)...STRONG H5 RIDGE WILL CONTINUE
TO DOMINATE THE WEATHER PATTERN THROUGH THE PERIOD...ALTHOUGH THERE
DOES APPEAR TO BE POTENTIAL FOR SFC FRONT STALLING NEAR THE AREA
BRINGING THE CHANCE FOR THUNDERSTORMS. LATEST OPERATIONAL MODELS
HAVE BACKED OFF PRECIP THREAT TO SOME DEGREE...FOCUSING WEST AND
NORTH OF THE CWA. WAS INCLINED TO BACK OFF POPS 10-15 PERCENT...BUT
WITH GEFS STILL INDICATING A FAIRLY ROBUST PRECIP SIGNAL HAVE OPTED
TO LET CURRENT CONSENSUS POPS REMAIN AS IS FOR THE TIME BEING.
OTHERWISE...WARM TEMPERATURES IN THE 90S TO LOW 100S WILL CONTINUE
THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1138 PM MDT TUE JUL 9 2013
THUNDERSTORMS CURRENTLY LOCATED ACROSS NORTHEAST COLORADO AND
SOUTHWEST NEBRASKA ARE HEADING TO THE SOUTHEAST...AND WILL LIKELY
MOVE BETWEEN KGLD AND KMCK. HOWEVER...SHOWERS AND POSSIBLY
THUNDERSTORMS COULD DEVELOP ALONG AN OUTFLOW BOUNDARY MOVING
TOWARDS KGLD OVER THE NEXT COUPLE OF HOURS. HAVE OPTED NOT TO
MENTION VCTS AT KGLD AS ACTIVITY SEEMS TO BE DIMINISHING BUT WILL
INCLUDE VCSH. WINDS WILL BE PROBLEMATIC WITH LINGERING OUTFLOW
BOUNDARIES AND COLD FRONT. SOUTHEAST WINDS SHOULD PICK UP LATE THIS
MORNING AND COULD BECOME GUSTY. SHOWERS AND THUNDERSTORMS ARE
EXPECTED TO DEVELOP AGAIN DURING THE LATE AFTERNOON AND MAY
APPROACH KGLD DURING THE EVENING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...RRH
SHORT TERM...LOCKHART
LONG TERM...JRM
AVIATION...RRH
AREA FORECAST DISCUSSION
NWS JACKSON KY
601 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 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 131 PM EDT WED JUL 10 2013
COLD FRONT CURRENTLY OVER FAR NORTHWEST INDIANA 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...WITH ALL TAF SITES EXPECTED TO BE AFFECTED LATE THIS
AFTERNOON AND INTO THE OVERNIGHT PERIOD. OUTSIDE OF THUNDERSTORMS
MOST AREAS WILL SEE VFR CONDITIONS THIS AFTERNOON...BUT AFTER MORE
WIDESPREAD PRECIPITATION MOVES IN LATER DO EXPECT CONDITIONS TO
DETERIORATE TONIGHT TO MVFR TO IFR. CONDITIONS SHOULD IMPROVE BACK TO
VFR BEFORE 18Z ON THURSDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR KYZ044-050>052-
058>060-068-069-079-080-083>088-104-106>120.
&&
$$
UPDATE...SBH
SHORT TERM...SBH
LONG TERM...JJ
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS JACKSON KY
334 PM EDT WED JUL 10 2013
.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 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 131 PM EDT WED JUL 10 2013
COLD FRONT CURRENTLY OVER FAR NORTHWEST INDIANA 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...WITH ALL TAF SITES EXPECTED TO BE AFFECTED LATE THIS
AFTERNOON AND INTO THE OVERNIGHT PERIOD. OUTSIDE OF THUNDERSTORMS
MOST AREAS WILL SEE VFR CONDITIONS THIS AFTERNOON...BUT AFTER MORE
WIDESPREAD PRECIPITATION MOVES IN LATER DO EXPECT CONDITIONS TO
DETERIORATE TONIGHT TO MVFR TO IFR. CONDITIONS SHOULD IMPROVE BACK TO
VFR BEFORE 18Z ON THURSDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR KYZ044-050>052-
058>060-068-069-079-080-083>088-104-106>120.
&&
$$
SHORT TERM...SBH
LONG TERM...JJ
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS JACKSON KY
304 PM EDT WED JUL 10 2013
.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 304 PM EDT WED JUL 10 2013
UPDATED DISCUSSION WILL FOLLOW SHORTLY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 131 PM EDT WED JUL 10 2013
COLD FRONT CURRENTLY OVER FAR NORTHWEST INDIANA 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...WITH ALL TAF SITES EXPECTED TO BE AFFECTED LATE THIS
AFTERNOON AND INTO THE OVERNIGHT PERIOD. OUTSIDE OF THUNDERSTORMS
MOST AREAS WILL SEE VFR CONDITIONS THIS AFTERNOON...BUT AFTER MORE
WIDESPREAD PRECIPITATION MOVES IN LATER DO EXPECT CONDITIONS TO
DETERIORATE TONIGHT TO MVFR TO IFR. CONDITIONS SHOULD IMPROVE BACK TO
VFR BEFORE 18Z ON THURSDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR KYZ044-050>052-
058>060-068-069-079-080-083>087-104-106>117-119.
&&
$$
SHORT TERM...SBH
LONG TERM...JJ
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
115 PM EDT WED JUL 10 2013
...Updated Aviation Discussion...
.FORECAST UPDATE...
Issued at Noon EDT Wed Jul 10 2013
After coordination with neighboring offices, decided to go ahead
with a flash flood watch in the areas that had the lowest 1-hour
flash flood guidance over the eastern forecast area. The I-65
corridor around Louisville has higher guidance, but with timing of
storms around the afternoon rush hour decided to err on the side of
caution and throw them in as well. Bust potential on the western
side of the area is how long the subsidence from the decaying storms
over Illinois continues to keep a cap over that area. Still, surface
temperatures are rising quickly over our area, so CAPEs already are
up around 3-4 thousand. All we need is a trigger to get these
storms to push through, and still think that will be from the north.
Issued at 945 AM EDT Wed Jul 10 2013
Local WRF and to some extent the HRRR pick up well on current spread
of convection out to our west and north this morning. Bumped up pops
a little over my southwest zones, where some scattered storms have
popped up this morning. Cloud cover is coming in ahead of the
central Illinois convection as well as with the cells to our west.
These clouds should help to temper our highs some today, but
dewpoints are fairly highs, so heat indices likely still will top
out in the mid/upper 90s, perhaps even 100 in the SDF metro.
Storms firing off to our west indicate somewhat of an uncapped
atmosphere, but AMDAR sounding out of SDF has a weak cap at 800 mb,
possibly from sinking air with the cirrus shield our ahead of those
storms in central Illinois. As of this writing, that subsidence
looks like it is weakening the cells just west of Hancock and Ohio
counties. Think this cap will be long enough to allow what the local
WRF shows as a line of storms moving in from the north later this
afternoon. By then soundings indicate plenty of CAPE despite the
cloud cover, so these storms will have enough instability to stay
together and producing damaging winds and possibly some hail. We`ll
have to get fairly tall storms to get the hail to survive down to
the surface, given a very moist airmass in place.
&&
.SHORT TERM (Now through Thursday)...
Issued at 316 AM EDT Wed Jul 10 2013
...Strong to Severe Storms Likely This Afternoon Along With Locally
Heavy Rainfall...
In the near term, passing mid-level wave now in Ohio will continue
to track eastward early this morning. Bulk of the convection
associated with the wave will pass northeast of our area, but some
isolated-scattered showers will be possible mainly across our
eastern half this morning. Clouds are rapidly clearing out to the
west, so we should see some partial clearing by sunrise in the
central and western sections. Temperatures will remain for the
remainder of the night with readings bottoming out in the
lower-middle 70s in most locations with upper 70s being more likely
down in the urban centers.
Next mid-level wave within the mean flow will approach the region
later this morning and into the afternoon hours. Expect convection
to develop over the next few hours from MO into IL with much of
region remaining fairly dry. In fact, it appears that we`ll likely
see some partly to mostly sunny skies this morning which will allow
solar insolation to really get temperatures warmed up. By mid-late
morning, convection to our northwest will begin to push eastward.
As the mid-level wave and associated surface boundary approach, we
expect convection to become more widespread during the afternoon and
into the evening hours.
Regarding convective potential and intensity, much of our region
will reside on the southern edge of the westerlies this afternoon.
This places much of the better shear to our north. However, with
the expected insolation this morning, we should see temperatures
warm into the upper 80s and perhaps lower 90s in some spots. This
combined with dewpoints in the lower-mid 70s will result in strong
instability developing as cooler mid-level temperatures overspread
the region.
Convection will probably be multi-modal with lines and segments
being likely. Given the decreasing shear profile from NE to SW
across our region, it appears that damaging winds/microbursts and
large hail will be the primary severe weather threats across our
region. With the wet ground in many places in central KY,
sub-severe winds could easily result in trees coming down fairly
easily. In addition to the severe weather threat, precipitable
water values are still forecast to run quite high this afternoon
with readings in the 1.9-2.0 inch range. This will result in
locally heavy rainfall with any of the storms that develop. Given
the rainfall over the past weekend, we are still dealing with fairly
wet grounds. Thus, the torrential rainfall with this afternoon`s
storms will have the capability of producing flash flooding. The
storms look to have some movement to them, so the flooding threat
could be more attributed to training of cells as well.
Showers and thunderstorms are expected to continue into the evening
hours, but should diminish with the loss of daytime heating this
evening. We should see a diminishing trend of PoPs from NW to SE
through the overnight hours with much of southern Indiana and
western/NC KY going dry by Thursday morning. Overnight lows will
cool into the 60s. A few scattered storms will be possible across
the east/southeast Thursday morning and into the early afternoon
hours, but most locations should see dry conditions by Thursday
evening. Highs Thursday will be cooler than Wednesday with readings
in the lower 80s.
.LONG TERM (Thursday Night through Tuesday)...
Issued at 302 AM EDT Wed Jul 10 2013
Drier and cooler air will be working its way into the area Thursday
night in the wake of the cold front. At the surface high pressure
will build in across the Ohio Valley through Friday. A trough aloft
will keep the region in northwesterly flow through Friday, before a
ridge builds across the Great Lakes region.
Dry conditions look to prevail through the weekend, though diurnal
storms will begin creeping back towards the far southeastern
portions of the forecast area by Sunday afternoon. Temperatures will
be coolest at the beginning of the period. Lows on Friday morning
will be in the low to mid 60s with highs in the low to mid 80s. By
Sunday lows will be in the upper 60s with highs in the upper 80s.
Moisture return will continue through the beginning of the next work
week. Isolated to scattered afternoon thunderstorms will be possible
Monday and Tuesday afternoons, especially across south central
Kentucky. Temperatures will continue the slow warming trend with
highs in the upper 80s to lower 90s by Tuesday and lows in the lower
70s.
&&
.AVIATION (18Z TAF Update)...
Issued at 115 PM EDT Wed Jul 10 2013
Atmosphere becoming more unstable with heating and high low-level
humidity. Have storms firing up near each of the sites, though
closest to SDF this hour. Expect a more solid line to move in from
the north, though if the more isolated convection over Kentucky
becomes more widespread that will poke some holes in anything moving
in from the north. For now have tried to place the timing of this
line into each of the sites with stronger wind gusts and IFR
restrictions. Lingering moisture overnight may lead to some MVFR
cigs and vsby into daybreak. Expect a front to pass through the
sites late this evening, bringing more solid northerly winds during
the day Thursday.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR INZ077>079-091-092.
KY...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR KYZ029>043-045>049-
053>057-064>067-076>078-081-082.
$$
Updates..........RJS
Short Term.......MJ
Long Term........EER
Aviation.........RJS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1205 PM EDT WED JUL 10 2013
.FORECAST UPDATE...
Issued at Noon EDT Wed Jul 10 2013
After coordination with neighboring offices, decided to go ahead
with a flash flood watch in the areas that had the lowest 1-hour
flash flood guidance over the eastern forecast area. The I-65
corridor around Louisville has higher guidance, but with timing of
storms around the afternoon rush hour decided to err on the side of
caution and throw them in as well. Bust potential on the western
side of the area is how long the subsidence from the decaying storms
over Illinois continues to keep a cap over that area. Still, surface
temperatures are rising quickly over our area, so CAPEs already are
up around 3-4 thousand. All we need is a trigger to get these
storms to push through, and still think that will be from the north.
Issued at 945 AM EDT Wed Jul 10 2013
Local WRF and to some extent the HRRR pick up well on current spread
of convection out to our west and north this morning. Bumped up pops
a little over my southwest zones, where some scattered storms have
popped up this morning. Cloud cover is coming in ahead of the
central Illinois convection as well as with the cells to our west.
These clouds should help to temper our highs some today, but
dewpoints are fairly highs, so heat indices likely still will top
out in the mid/upper 90s, perhaps even 100 in the SDF metro.
Storms firing off to our west indicate somewhat of an uncapped
atmosphere, but AMDAR sounding out of SDF has a weak cap at 800 mb,
possibly from sinking air with the cirrus shield our ahead of those
storms in central Illinois. As of this writing, that subsidence
looks like it is weakening the cells just west of Hancock and Ohio
counties. Think this cap will be long enough to allow what the local
WRF shows as a line of storms moving in from the north later this
afternoon. By then soundings indicate plenty of CAPE despite the
cloud cover, so these storms will have enough instability to stay
together and producing damaging winds and possibly some hail. We`ll
have to get fairly tall storms to get the hail to survive down to
the surface, given a very moist airmass in place.
&&
.SHORT TERM (Now through Thursday)...
Issued at 316 AM EDT Wed Jul 10 2013
...Strong to Severe Storms Likely This Afternoon Along With Locally
Heavy Rainfall...
In the near term, passing mid-level wave now in Ohio will continue
to track eastward early this morning. Bulk of the convection
associated with the wave will pass northeast of our area, but some
isolated-scattered showers will be possible mainly across our
eastern half this morning. Clouds are rapidly clearing out to the
west, so we should see some partial clearing by sunrise in the
central and western sections. Temperatures will remain for the
remainder of the night with readings bottoming out in the
lower-middle 70s in most locations with upper 70s being more likely
down in the urban centers.
Next mid-level wave within the mean flow will approach the region
later this morning and into the afternoon hours. Expect convection
to develop over the next few hours from MO into IL with much of
region remaining fairly dry. In fact, it appears that we`ll likely
see some partly to mostly sunny skies this morning which will allow
solar insolation to really get temperatures warmed up. By mid-late
morning, convection to our northwest will begin to push eastward.
As the mid-level wave and associated surface boundary approach, we
expect convection to become more widespread during the afternoon and
into the evening hours.
Regarding convective potential and intensity, much of our region
will reside on the southern edge of the westerlies this afternoon.
This places much of the better shear to our north. However, with
the expected insolation this morning, we should see temperatures
warm into the upper 80s and perhaps lower 90s in some spots. This
combined with dewpoints in the lower-mid 70s will result in strong
instability developing as cooler mid-level temperatures overspread
the region.
Convection will probably be multi-modal with lines and segments
being likely. Given the decreasing shear profile from NE to SW
across our region, it appears that damaging winds/microbursts and
large hail will be the primary severe weather threats across our
region. With the wet ground in many places in central KY,
sub-severe winds could easily result in trees coming down fairly
easily. In addition to the severe weather threat, precipitable
water values are still forecast to run quite high this afternoon
with readings in the 1.9-2.0 inch range. This will result in
locally heavy rainfall with any of the storms that develop. Given
the rainfall over the past weekend, we are still dealing with fairly
wet grounds. Thus, the torrential rainfall with this afternoon`s
storms will have the capability of producing flash flooding. The
storms look to have some movement to them, so the flooding threat
could be more attributed to training of cells as well.
Showers and thunderstorms are expected to continue into the evening
hours, but should diminish with the loss of daytime heating this
evening. We should see a diminishing trend of PoPs from NW to SE
through the overnight hours with much of southern Indiana and
western/NC KY going dry by Thursday morning. Overnight lows will
cool into the 60s. A few scattered storms will be possible across
the east/southeast Thursday morning and into the early afternoon
hours, but most locations should see dry conditions by Thursday
evening. Highs Thursday will be cooler than Wednesday with readings
in the lower 80s.
.LONG TERM (Thursday Night through Tuesday)...
Issued at 302 AM EDT Wed Jul 10 2013
Drier and cooler air will be working its way into the area Thursday
night in the wake of the cold front. At the surface high pressure
will build in across the Ohio Valley through Friday. A trough aloft
will keep the region in northwesterly flow through Friday, before a
ridge builds across the Great Lakes region.
Dry conditions look to prevail through the weekend, though diurnal
storms will begin creeping back towards the far southeastern
portions of the forecast area by Sunday afternoon. Temperatures will
be coolest at the beginning of the period. Lows on Friday morning
will be in the low to mid 60s with highs in the low to mid 80s. By
Sunday lows will be in the upper 60s with highs in the upper 80s.
Moisture return will continue through the beginning of the next work
week. Isolated to scattered afternoon thunderstorms will be possible
Monday and Tuesday afternoons, especially across south central
Kentucky. Temperatures will continue the slow warming trend with
highs in the upper 80s to lower 90s by Tuesday and lows in the lower
70s.
&&
.AVIATION (12Z TAF Update)...
Issued at 644 AM EDT Wed Jul 10 2013
VFR conditions are expected for early portion of the TAF period.
Mid-level clouds associated with departing mid-level wave are moving
out and have cleared out of the terminals. So for the next few
hours, we`ll see mostly clear skies but should see a cu field
develop toward late morning.
Surface cold front and next mid-level wave are currently out to our
west and are heading eastward. These features will impact the
region this afternoon during peak heating. This should result in
convective development across the region. Still a little uncertain
with regards to overall convective evolution, so plan on going with
VCTS at the terminals after 10/18Z. Convection will likely linger
into the evening/overnight hours before diminishing. Outside of
storms, VFR conditions will prevail, but if a storm impacts the
terminal, a drop to IFR conditions due to heavy rain is likely.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR INZ077>079-091-092.
KY...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR KYZ029>043-045>049-
053>057-064>067-076>078-081-082.
$$
Updates..........RJS
Short Term.......MJ
Long Term........EER
Aviation.........MJ
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
947 AM EDT WED JUL 10 2013
.FORECAST UPDATE...
Issued at 945 AM EDT Wed Jul 10 2013
Local WRF and to some extent the HRRR pick up well on current spread
of convection out to our west and north this morning. Bumped up pops
a little over my southwest zones, where some scattered storms have
popped up this morning. Cloud cover is coming in ahead of the
central Illinois convection as well as with the cells to our west.
These clouds should help to temper our highs some today, but
dewpoints are fairly highs, so heat indices likely still will top
out in the mid/upper 90s, perhaps even 100 in the SDF metro.
Storms firing off to our west indicate somewhat of an uncapped
atmosphere, but AMDAR sounding out of SDF has a weak cap at 800 mb,
possibly from sinking air with the cirrus shield our ahead of those
storms in central Illinois. As of this writing, that subsidence
looks like it is weakening the cells just west of Hancock and Ohio
counties. Think this cap will be long enough to allow what the local
WRF shows as a line of storms moving in from the north later this
afternoon. By then soundings indicate plenty of CAPE despite the
cloud cover, so these storms will have enough instability to stay
together and producing damaging winds and possibly some hail. We`ll
have to get fairly tall storms to get the hail to survive down to
the surface, given a very moist airmass in place.
&&
.SHORT TERM (Now through Thursday)...
Issued at 316 AM EDT Wed Jul 10 2013
...Strong to Severe Storms Likely This Afternoon Along With Locally
Heavy Rainfall...
In the near term, passing mid-level wave now in Ohio will continue
to track eastward early this morning. Bulk of the convection
associated with the wave will pass northeast of our area, but some
isolated-scattered showers will be possible mainly across our
eastern half this morning. Clouds are rapidly clearing out to the
west, so we should see some partial clearing by sunrise in the
central and western sections. Temperatures will remain for the
remainder of the night with readings bottoming out in the
lower-middle 70s in most locations with upper 70s being more likely
down in the urban centers.
Next mid-level wave within the mean flow will approach the region
later this morning and into the afternoon hours. Expect convection
to develop over the next few hours from MO into IL with much of
region remaining fairly dry. In fact, it appears that we`ll likely
see some partly to mostly sunny skies this morning which will allow
solar insolation to really get temperatures warmed up. By mid-late
morning, convection to our northwest will begin to push eastward.
As the mid-level wave and associated surface boundary approach, we
expect convection to become more widespread during the afternoon and
into the evening hours.
Regarding convective potential and intensity, much of our region
will reside on the southern edge of the westerlies this afternoon.
This places much of the better shear to our north. However, with
the expected insolation this morning, we should see temperatures
warm into the upper 80s and perhaps lower 90s in some spots. This
combined with dewpoints in the lower-mid 70s will result in strong
instability developing as cooler mid-level temperatures overspread
the region.
Convection will probably be multi-modal with lines and segments
being likely. Given the decreasing shear profile from NE to SW
across our region, it appears that damaging winds/microbursts and
large hail will be the primary severe weather threats across our
region. With the wet ground in many places in central KY,
sub-severe winds could easily result in trees coming down fairly
easily. In addition to the severe weather threat, precipitable
water values are still forecast to run quite high this afternoon
with readings in the 1.9-2.0 inch range. This will result in
locally heavy rainfall with any of the storms that develop. Given
the rainfall over the past weekend, we are still dealing with fairly
wet grounds. Thus, the torrential rainfall with this afternoon`s
storms will have the capability of producing flash flooding. The
storms look to have some movement to them, so the flooding threat
could be more attributed to training of cells as well.
Showers and thunderstorms are expected to continue into the evening
hours, but should diminish with the loss of daytime heating this
evening. We should see a diminishing trend of PoPs from NW to SE
through the overnight hours with much of southern Indiana and
western/NC KY going dry by Thursday morning. Overnight lows will
cool into the 60s. A few scattered storms will be possible across
the east/southeast Thursday morning and into the early afternoon
hours, but most locations should see dry conditions by Thursday
evening. Highs Thursday will be cooler than Wednesday with readings
in the lower 80s.
.LONG TERM (Thursday Night through Tuesday)...
Issued at 302 AM EDT Wed Jul 10 2013
Drier and cooler air will be working its way into the area Thursday
night in the wake of the cold front. At the surface high pressure
will build in across the Ohio Valley through Friday. A trough aloft
will keep the region in northwesterly flow through Friday, before a
ridge builds across the Great Lakes region.
Dry conditions look to prevail through the weekend, though diurnal
storms will begin creeping back towards the far southeastern
portions of the forecast area by Sunday afternoon. Temperatures will
be coolest at the beginning of the period. Lows on Friday morning
will be in the low to mid 60s with highs in the low to mid 80s. By
Sunday lows will be in the upper 60s with highs in the upper 80s.
Moisture return will continue through the beginning of the next work
week. Isolated to scattered afternoon thunderstorms will be possible
Monday and Tuesday afternoons, especially across south central
Kentucky. Temperatures will continue the slow warming trend with
highs in the upper 80s to lower 90s by Tuesday and lows in the lower
70s.
&&
.AVIATION (12Z TAF Update)...
Issued at 644 AM EDT Wed Jul 10 2013
VFR conditions are expected for early portion of the TAF period.
Mid-level clouds associated with departing mid-level wave are moving
out and have cleared out of the terminals. So for the next few
hours, we`ll see mostly clear skies but should see a cu field
develop toward late morning.
Surface cold front and next mid-level wave are currently out to our
west and are heading eastward. These features will impact the
region this afternoon during peak heating. This should result in
convective development across the region. Still a little uncertain
with regards to overall convective evolution, so plan on going with
VCTS at the terminals after 10/18Z. Convection will likely linger
into the evening/overnight hours before diminishing. Outside of
storms, VFR conditions will prevail, but if a storm impacts the
terminal, a drop to IFR conditions due to heavy rain is likely.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Update...........RJS
Short Term.......MJ
Long Term........EER
Aviation.........MJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
131 AM EDT WED JUL 10 2013
.UPDATE...
ISSUED AT 1215 AM EDT WED JUL 10 2013
WITHIN THE LAST COUPLE OF HOURS...SCT SHOWERS STARTED DEVELOPING
ACROSS LMK/S CWA...AND HAVE NOW STARTED DEVELOPING ACROSS THE NORTH
HALF OF OUR CWA OVER THE LAST 30 MINS/HOUR. UPDATED GRIDS TO REFLECT
SCT POPS ACROSS MUCH OF THE REGION OVER THE NEXT FEW HOURS. HI-RES
MODELS HAVE VERY LITTLE HANDLE ON PLACEMENT OF ONGOING OR FUTURE
CONVECTIVE DEVELOPMENT...SO BASED ON RADAR TRENDS FELT IT WAS BETTER
TO PUT IN SCT ACROSS MUCH OF THE REGION AS IT SEEMS MUCH OF THE
CWA WILL BE IN THE VICINITY OR DIRECT PATH OF A SHOWER OVER THE
NEXT FEW HOURS. WITH MOIST AND UNSTABLE ENVIRONMENT IN PLACE...DO NOT
SEE ANY REASON FOR OVERALL SHOWER ACTIVITY TO DIMINISH ONCE FORMED.
BUT WITH A STRONG LLVL INVERSION IN PLACE AS WELL...NOT EXPECTING ANY
THUNDERSTORM DEVELOPMENT DURING THE OVERNIGHT. ALSO...LOADED IN
LATEST OBSERVATIONS TO MAKE SURE OTHER SHORT TERM FORECAST PARAMETERS
WERE UP TO SPEED ON CURRENT CONDITIONS.
UPDATE ISSUED AT 1056 PM EDT TUE JUL 9 2013
UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL
TRENDS. SPOTTER REPORTS CAME IN FROM MCCREARY COUNTY WITH TREES DOWN
AND REPORTS OF FLOODING. THE ONE SPOTTER TOLD US THEY HAVE LIVED IN
THE SAME PLACE FOR 44 YEARS...AND THEY NEVER SAW THE WATER RAISE THAT
QUICKLY. WITH THE SATURATED GROUND FROM ALL THE RECENT RAINFALL AND
THE DEWPOINTS IN THE 70S...LOCALIZED FLASH FLOODING WILL BE A REAL
POSSIBILITY AND WILL NEED TO BE MONITORED CLOSELY. THE AREA RIVERS
HAVE NOW TEMPORARILY ALL FALLEN BELOW ACTION STAGE. WILL HAVE TO WAIT
AND SEE HOW MUCH RAIN WILL FALL OVER THE NEXT 24-36 HOURS. IT WILL
NOT TAKE MUCH TO GET THE RIVERS RISING AGAIN. SPC HAS PUT PART OF
EASTERN KENTUCKY IN A SLIGHT RISK FROM SEVERE THUNDERSTORMS. FROM
LOOKING AT THE NAM BUFR SOUNDINGS...THIS APPEARS TO HAVE A VERY LOW
CHANCE TO SEE MORE THAN ONE OR TWO SEVERE REPORTS AS THIS NEXT SYSTEM
MOVES THROUGH THE AREA WEDNESDAY NIGHT AND THURSDAY.
UPDATE ISSUED AT 755 PM EDT TUE JUL 9 2013
UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL
TRENDS. THE AREA SOUTH AND WEST OF JACKSON GOOD REALLY ACTIVE IN THE
LAST FEW HOURS. THE UNSTABLE MOIST AIR WAS REALLY PRIMED...ALL THAT
WAS NEEDED WAS THE CONVECTIVE INITIATION. ONE OF THE STORMS GOT
REALLY STRONG AND REACHED OUR RADAR BASED SEVERE WEATHER CRITERIA. NO
REPORTS HAVE BEEN REPORTED YET. THE MOISTURE LADEN IS CAPABLE OF
DUMPING A LOT OF RAIN IN A SHORT TIME. RADAR ESTIMATES OF GREATER
THAN TWO INCHES WAS RESPONSIBLE FOR PRODUCING SOME FLASH FLOODING IN
THE HOLLY HILL AREA. THE REST OF THE FORECAST IS ON TRACK.
&&
.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 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 130 AM EDT WED JUL 10 2013
SCT SHOWERS HAVE DEVELOPED ACROSS MUCH OF THE OHIO VALLEY OVERNIGHT AND
CONTINUE TO MOVE SE ACROSS THE CWA. THOUGH SHOWERS ARE QUITE LIGHT
AND SHOULD NOT HAVE MUCH IN THE WAY OF IMPACTS ON THE TAF
SITES...DECIDED TO GO AHEAD AND INCLUDE IN TAFS SINCE SOME RAIN
WILL BE DETECTED AT ALL SITES OVER THE NEXT FEW HOURS. AS WE GO INTO
THE DAYTIME HOURS...SCT TSRA WILL BEGIN TO DEVELOP ACROSS MUCH OF THE
REGION IN RESPONSE TO AN APPROACHING FRONTAL SYSTEM. WENT WITH
PREVIOUS FORECASTS MENTION OF VCTS INSTEAD OF PREDOMINATE TSRA SINCE
IT IS STILL UNCERTAIN IF SCT CONVECTION WILL DIRECTLY IMPACT TAF
SITES...AND IF SO WHEN AND HOW MUCH IMPACT WILL IT HAVE. AS THE FRONT
CONTINUES TO NEAR OVERNIGHT...SHOWERS AND THUNDERSTORMS WILL BECOME
MORE WIDESPREAD WITH BETTER CONFIDENCE OF IMPACTS BEING FELT AT ALL
TAF SITES. FORECAST SOUNDINGS CONTINUE TO SUPPORT THE POTENTIAL FOR
HEAVY DOWNPOURS WITH ANY OF THESE SHOWERS AND THUNDERSTORMS TODAY AND
TONIGHT...SO COULD SEE VIS LOWER SUBSTANTIALLY FOR A PERIOD OF TIME IF
SHRA/TSRA PASSES OVERHEAD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...RAY
LONG TERM...GREIF
AVIATION...JMW
AREA FORECAST DISCUSSION
NWS JACKSON KY
1215 AM EDT WED JUL 10 2013
.UPDATE...
ISSUED AT 1215 AM EDT WED JUL 10 2013
WITHIN THE LAST COUPLE OF HOURS...SCT SHOWERS STARTED DEVELOPING
ACROSS LMK/S CWA...AND HAVE NOW STARTED DEVELOPING ACROSS THE NORTH
HALF OF OUR CWA OVER THE LAST 30 MINS/HOUR. UPDATED GRIDS TO REFLECT
SCT POPS ACROSS MUCH OF THE REGION OVER THE NEXT FEW HOURS. HI-RES
MODELS HAVE VERY LITTLE HANDLE ON PLACEMENT OF ONGOING OR FUTURE
CONVECTIVE DEVELOPMENT...SO BASED ON RADAR TRENDS FELT IT WAS BETTER
TO PUT IN SCT ACROSS MUCH OF THE REGION AS IT SEEMS MUCH OF THE
CWA WILL BE IN THE VICINITY OR DIRECT PATH OF A SHOWER OVER THE
NEXT FEW HOURS. WITH MOIST AND UNSTABLE ENVIRONMENT IN PLACE...DO NOT
SEE ANY REASON FOR OVERALL SHOWER ACTIVITY TO DIMINISH ONCE FORMED.
BUT WITH A STRONG LLVL INVERSION IN PLACE AS WELL...NOT EXPECTING ANY
THUNDERSTORM DEVELOPMENT DURING THE OVERNIGHT. ALSO...LOADED IN
LATEST OBSERVATIONS TO MAKE SURE OTHER SHORT TERM FORECAST PARAMTERS
WERE UP TO SPEED ON CURRENT CONDITIONS.
UPDATE ISSUED AT 1056 PM EDT TUE JUL 9 2013
UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL
TRENDS. SPOTTER REPORTS CAME IN FROM MCCREARY COUNTY WITH TREES DOWN
AND REPORTS OF FLOODING. THE ONE SPOTTER TOLD US THEY HAVE LIVED IN
THE SAME PLACE FOR 44 YEARS...AND THEY NEVER SAW THE WATER RAISE THAT
QUICKLY. WITH THE SATURATED GROUND FROM ALL THE RECENT RAINFALL AND
THE DEWPOINTS IN THE 70S...LOCALIZED FLASH FLOODING WILL BE A REAL
POSSIBILITY AND WILL NEED TO BE MONITORED CLOSELY. THE AREA RIVERS
HAVE NOW TEMPORARILY ALL FALLEN BELOW ACTION STAGE. WILL HAVE TO WAIT
AND SEE HOW MUCH RAIN WILL FALL OVER THE NEXT 24-36 HOURS. IT WILL
NOT TAKE MUCH TO GET THE RIVERS RISING AGAIN. SPC HAS PUT PART OF
EASTERN KENTUCKY IN A SLIGHT RISK FROM SEVERE THUNDERSTORMS. FROM
LOOKING AT THE NAM BUFR SOUNDINGS...THIS APPEARS TO HAVE A VERY LOW
CHANCE TO SEE MORE THAN ONE OR TWO SEVERE REPORTS AS THIS NEXT SYSTEM
MOVES THROUGH THE AREA WEDNESDAY NIGHT AND THURSDAY.
UPDATE ISSUED AT 755 PM EDT TUE JUL 9 2013
UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL
TRENDS. THE AREA SOUTH AND WEST OF JACKSON GOOD REALLY ACTIVE IN THE
LAST FEW HOURS. THE UNSTABLE MOIST AIR WAS REALLY PRIMED...ALL THAT
WAS NEEDED WAS THE CONVECTIVE INITIATION. ONE OF THE STORMS GOT
REALLY STRONG AND REACHED OUR RADAR BASED SEVERE WEATHER CRITERIA. NO
REPORTS HAVE BEEN REPORTED YET. THE MOISTURE LADEN IS CAPABLE OF
DUMPING A LOT OF RAIN IN A SHORT TIME. RADAR ESTIMATES OF GREATER
THAN TWO INCHES WAS RESPONSIBLE FOR PRODUCING SOME FLASH FLOODING IN
THE HOLLY HILL AREA. THE REST OF THE FORECAST IS ON TRACK.
&&
.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 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 755 PM EDT TUE JUL 9 2013
LOTS OF THUNDERSTORMS NEAR THE TAF STATIONS THIS EVENING. THE RADAR
IS INDICATING OUTFLOW BOUNDARIES BEING PRODUCED BY THE THUNDERSTORMS
MOVING MANY MILES OUT AHEAD OF THE STORMS. THIS WOULD MEAN THAT AN
UNEXPECTED LOW LEVEL WIND SHEAR WELL AHEAD OF THE APPROACHING STORM.
LOZ SHOULD BE SEEING A THUNDERSTORM AT THE STATION BETWEEN 00-01Z. FOR
FOG AND MIST...WENT WITH PERSISTENCE FOR THE FORECAST. THIS MAY HAVE
TO BE RETHOUGHT IF LOZ GET LOTS OF RAIN THIS NEXT HOUR. TOMORROW
SHOULD HAVE MORE CONVECTIVE ACTIVITY THAN TODAY WITH A SLIGHT RISK OF
SEVERE THUNDERSTORMS ACROSS THE AREA.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...RAY
LONG TERM...GREIF
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS GRAY ME
616 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...
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 /22Z 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...NONE.
NH...FLASH FLOOD WATCH UNTIL 10 PM EDT THIS EVENING FOR NHZ003-005-
007>010-013-014.
MARINE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
931 PM EDT THU JUL 11 2013
.SYNOPSIS...
A COLD FRONT WILL REMAIN STALLED OVER THE DELMARVA PENINSULA AND
SOUTHEASTERN VIRGINIA THROUGH THIS WEEKEND. HIGH PRESSURE WILL
BUILD WEST FROM THE WESTERN ATLANTIC EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH FRIDAY/...
LTST SFC ANALY DEPICTS A STALLED CDFNT ALONG THE I-95 CRRDR...
WHILE HIPRES RESIDES OVER THE GRTLKS. AN ANIMATION OF WATER
VAPOR IMGRY SUGGESTS AN UPR LOW ROTATING ABV THE SFC HIGH...ALSO
OVER THE GRTLKS.
ALTHO CWFA WL BE ON THE NW SIDE OF THE CDFNT...THERE ARE SVRL
FACTORS SUPPORTING A ROUND OF SHRA/TSRA OVNGT...AS EVIDENCED BY
RECENT RADAR TRENDS. FIRST...HGTS WL BE DROPPING AS THE UPR LOW
NEARS. SECONDLY...THE CWFA WL BE W/IN RRQ OF AN UPR JET. ITS ONLY
ABT 60-70 KT...BUT IT/S SUFFICIENT TO SUPPORT LIFT. THIRD...
BELIEVE THAT THERE ARE/WL BE A CPL WK IMPULSES GLIDING ALONG THE
STALLED SFC BNDRY.
RECENT HRRR RUNS VERIFYING QUITE NICELY...AS SWRN CWFA FILLING IN
W/ PCPN ECHOES. HV ALREADY ADJUSTED DATABASE TO EMPHASIZE THAT
AREA FOR THE EVNG HRS. HV ALSO PAINTED THE OVNGT HRS ON THE WET
SIDE...W/ LKLY POPS JUST ABT EVERYWHERE AFTER MIDNGT. 00Z RAOBS
HINT AT MINIMAL INSTBY W/ A SMALL CAP. WL PLACE MORE WEIGHT ON
SHRA...BUT THINK THAT THERE WL BE ENUF ELEVATED INSTBY FOR A FEW
RUMBLES TOO.
THAT ROUND OF SHRA/STORMS SHUD CLR AREA BY SUNRISE. IN SPITE OF
LMTD INSTBY TMRW...THE H5 LOW WL BE CLOSEST TO CWFA DURING THE DAY.
WITH THAT IN MIND...COGNIZANT OF THE UPR JET SUPPORT...AND HINTS
AT SOME MID LVL OVERRUNNING...THINK THERE SHUD BE A 2ND ROUND OF
SHRA /OR MAYBE A STORM/ FRI AFTN. AFTER REDUCING POPS INTO CHC
FOR MOST AREAS...HV TAKEN IT BACK UP TO LKLY AGN FOR THE AFTN HRS.
ANY CHGS TO TEMPS/DEWPTS WL BE MINIMAL BASED ON LTST LAMP GDNC.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY/...
HIGH PRESSURE CONTINUES TO MOVE WESTWARD AND PUSH MOISTURE INTO THE
REGION. ROUNDS OF SHOWERS WILL MOVE ACROSS THE MID ATLANTIC INTO
SATURDAY. AS THE HIGH MOVES WESTWARD MOISTURE WILL MOVE TO THE
MOUNTAINS AND SUBSIDENCE WILL KICK IN OVER AREAS EAST OF THE BLUE
RIDGE. EASTERLY FLOW WILL CONTINUE THE BELOW NORMAL TEMP PERIOD.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
IN JULY THE MAJOR WX PROBLEMS WHICH COME TO MIND ARE HIGH HEAT..
SVR STORMS..AND FLSH FLDG. IT APPEARS THAT ALL OF THESE WL BE HELD
AT BAY DURG THE XTND PD. IF THE GFS IS TO BE BLVD...THE COMING UPR
LVL PATTERN IS SOMEWHAT OF AN ANACHRONISM FOR MID JUL. NRMLY ONE
WOULD XPCT TO SEE A SUBTROPICAL HIGH PARKED OFF THE CST BRINGING A
STREAM OF WARM MOIST AIR INTO THE MID ALTC WHICH WOULD BRING ABT
THE PSBLTY OF AFTN/EVE TSTMS...W/ THE PTNL FOR HEAT INDICES
REACHING ADSRY LVL.
OVR THE WKND THAT LOW IS SUPPOSED TO TRACK SLOWLY TO THE W AS
HIGH PRES CENTERED NEAR LONG ISLAND BUILDS INTO THE MID ALTC. THIS
WL KEEP THE NRML MID-JUL TROPICAL CHARACTERISTICS AT BAY - XPCT TO
SEE HIGHS IN THE 80S W/ LOWS IN THE L70S E OF I-95...60S W.
AS NEXT WK PROGRESSES THAT HIGH LOOKS TO TRACK FURTHER S...MOST
LKLY CAUSING THAT AIR MASS IN THE MID ATLC TO MODIFY AND BECOME
MORE "TYPICAL" W/ INCRSG HEAT AND HUMIDITY. PCPN LOOKS TO BE HELD
AT BAY THRU MID WK.
&&
.AVIATION /01Z FRIDAY THROUGH TUESDAY/...
SHRA/TSRA WL BECOME MORE NMRS OVNGT. VSBY IMPACTS WL BE LCLZD...
BUT POTENTIALY AOB IFR. DUE TO DIFFICULTIES PINPOINTING SPECIFICS
IN A TAF STYLE FCST...HV KEPT VSBYS IN MVFR. WL ADD DETAILS
IF/WHEN THAT BECOMES CLR. CIGS...ON THE OTHER HAND...SHUD BE
LWRG...SPCLY IN THE S/W WHERE RESIDUAL MSTR WL BE LEFT BHD BY
DAWN. ON TOP OF MVFR CIGS EVERYWHERE...AM TAKING STRONG GDNC
SIGNALS OF IFR FOR CHO.
FRI WL BE AN UNSETTLED DAY. AN UPR LOW WL ROTATE TWD AREA...
SUGGESTING THAT ANY BONOVC WL ONLY QUICKLY FILL BACK IN.
FURTHER...NLY SFC FLOW AND ELY FLOW JUST OFF THE SFC WL INHIBIT
MUCH DRYING W/IN THE COLUN. DO NOT XPCT CIGS TO RISE MUCH FM LVLS
JUST AFTER SUNRISE. FURTHER SHRA WL ONLY REINFORCE POTL
RESTRICTIONS. CONDS CUD REALLY DROP FRI NGT AS RAFL EXITS BUT
MOIST LLVL CONDS PREVAIL.
DIURNAL SHRA/TSRA WL BECOME INCRSGLY SCARCE THRU THE WKND INTO ELY
NEXT WK. THAT MEANS THAT VFR WL PREVAIL FOR A MAJORITY OF THE TIME.
&&
.MARINE...
LGT SLY FLOW OVER THE WATERS THIS EVNG. STALLED CDFNT WL BE
NEARBY...SO WINDS SHUD REMAIN LGT. WATERS WL EXPERIENCE A ROUND OF
SHRA/TSRA OVNGT. WINDS MAY GET A LTL GUSTY...BUT SUSPECT THAT HVY
RAIN WL BE THE PRIMARY THREAT.
MAY BE ABLE TO NUDGE THE FNT EWD FRI. IF SO...THERE CUD BE A SMALL
SURGE IN WNDS. DO NOT HV HIGH CONFIDENCE IN THAT SCENARIO ATTM.
CONCERNS ARE THAT AN APPROACHING UPR LOW WL SUPPORT MORE SHRA/TSRA
INSTEAD. DO NOT BELIEVE THAT ANYTHING WL BE STRONG ENUF FOR
SPECIAL MARINE WARNINGS AS THE LLVLS WL BE ON THE STBL SIDE.
HIGH PRES IS XPCTD TO BUILD INTO THE WATERS OVR THE WKND/INTO
NEXT WK. NO PROBS XPCTD.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...HTS
NEAR TERM...HTS
SHORT TERM...HAS
LONG TERM...WOODY!
AVIATION...HTS
MARINE...HTS/WOODY!
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1001 AM EDT WED JUL 10 2013
.SYNOPSIS...
UPPER LEVEL LOW PRESSURE WILL DRIFT EAST ACROSS THE NORTHEASTERN
STATES. HIGH PRESSURE WILL PERSIST OFFSHORE. A COLD FRONT IS
EXPECTED TO PASS THROUGH THE AREA THURSDAY BEFORE STALLING JUST TO
THE SOUTH THIS WEEKEND. AN UPPPER LEVEL AREA OF LOW PRESSURE MAY
TRACK INTO THE REGION DURING THE FIRST PART OF THE NEW WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
A SHORTWAVE TROUGH AHEAD OF THE MAIN UPPER LEVEL TROUGH ARE WELL
DEFINED ON WV IMAGERY THIS MORNING. CLOUD COVER AND LIGHT SHOWERS
HAVE INCREASED OVER THE CWA. SHOWERS ARE LIGHT BUT HIGH DEWPTS AND
PWAT VALUES NEAR 2 INCHES WILL OFFER A QUICK MODERATE SHOWER FOR THE
NEXT FEW HOURS.
THIS AFTERNOON... SHORTWAVE NEARS THE CWA AND THUNDERSTORMS WILL BE
POSSIBLE. SW FLOW WILL MAINTAIN THE SFC TROUGH ACROSS THE PIEDMONT
REGION. 12Z MODIFIED IAD RAOB PROVES SATURATED COLUMN. HIGH TEMPS
ARE EXPECTED TO REACH THE UPPER 80S AND SFC BASED INSTABILITY IS
EXPECTED TO REACH AROUND 2000 J/KG. LITTLE SHEAR AND CLOUD COVER
WILL PLAY A LARGE ROLE IN DAMPENING THE EFFECTS OF A SVR THREAT
THIS AFTERNOON AND EVENING. ISO-SCT THUNDERSTORMS ARE POSSIBLE
AFTER 12 PM TODAY WITH THE MAIN THREAT FOR FLASH FLOODING. 1-HR
FFG IS LOWER IN WASH DC AND BALT AND WESTERN SUBURBS. ISO THREAT
FOR WET MICROBURSTS LATE THIS AFTERNOON WITH DCAPE VALUES NEAR 500
J/KG.
STRONG THUNDERSTORMS WILL INCREASE IN COVERAGE ACROSS THE OHIO
VALLEY TODAY. THESE THUNDERSTORMS WILL MOVE INTO THE MID ATLANTIC
THIS EVENING. 11Z HRRR HAS SHOWERS AND THUNDERSTORMS MOVING INTO THE
MTNS AROUND 00Z. ACTIVITY IS EXPECTED TO WANE AS IT MOVES OVER THE
MTNS BUT SHOWERS AND ELEVATED THUNDERSTORMS MAY BE POSSIBLE
OVERNIGHT.
&&
.SHORT TERM / THURSDAY THROUGH 6 AM THURSDAY/...
INSTABILITY REMAINS THROUGH THE NIGHT AS THE TROUGH SHIFT
EAST INTO THE MID-ATLANTIC. IN FACT...CHANCE POPS WERE INTRODUCED
FOR MOST OF THE AREA LATE TONIGHT AS ELEVATED INSTABILITY INCREASES
OVERNIGHT. MIN TEMPS UP TO 10 DEGREES ABOVE NORMAL WITH CLOUDS AND
MOISTURE...GENERALLY LOW TO MID 70S PER MAV/MET/SREF BLEND.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
SVRL DAYS AGO I HV TO ADMIT I HAD MY DOUBTS WHEN THE XTND MDLS
WERE PROJECTING A CD FNT TO PUSH THRU THE MID ATLC ON THU AND PUSH
ALL THE WAY TO GA. THIS IS NOT NRML MID JUL FARE...BUT IT INDEED
APPEARS THAT THE MDLS HAD A GOOD HANDLE ON WHAT IS XPCTD TO
HAPPEN.
AND W/ THAT FNT MOVG THRU THE AREA THU AFTN THERE`LL BE CHC FOR
PCPN/TSTMS. BOTH NAM/GFS ARE GIVING LKLY POPS. WE`VE DONE STUDIES
ON MDL POP VS. WHAT REALLY OCCURRED...AND IN THE SUMMER MONTHS
WHEN IN THE 60-70 PCNT RANGE MDLS TEND TO OVRFCST...WHICH MAKES
SENSE GIVEN THE NRMLY HIT OR MISS NAUTRE OF SUMMER STORMS. IN SOME
SEASONS 60-70 REALLY END UP AS CATEGORICAL BUT NOT SUMMER...SO
WE`LL STAY W/ THE CURRENT 60 POP FOR THU. TEMP WISE LATELY WE`VE
BEEN FCSTG A FEW DEGS TOO WARM...AND GIVEN THE CLD CVR/CHCS OF
PCPN WL HOLD HIGH TEMPS IN THE LM80S...XCPT MU80S IN THE CITIES.
TROF TO MOVE OFF THE CST FRI..BRINGING SOME CLRG TO THE RGN. HIGH
TEMPS AGN IN M80S. I DID A QUICK STUDY LAST WK ABT SUMMER TEMPS IN
THE 2000S...AND AGN TNGT SHOWS THAT FOR AVG TEMPS IN THE 2000S
THIS YR IS IN THE MIDDLE OF THE PACK - #6 AT BOTH DCA AND
BWI...AND THERE IS NOTHING NOTABLE IN THE XTND TO IMPLY THAT THE
RANKING IS GOING TO CLIMB IN THE COMING DAYS.
ERLR THERE WAS A DEGREE OF DISAGREEMENT IN THE MDLS - U.S. MDLS
SHOWED A CUT OFF LOW FORMING OVR NEW ENGLAND THIS WKND WHILE 12Z
ECM SHOWED THE TROF AS BEING PROGRESSIVE AND MOVING INTO
ALTC....LVG HIGH PRES OVR THE MID ALTC. BUT AS I`M WRITING THE NEW
ECM IS COMING IN...AND ALSO SHOWING THE LOW OVR NEW ENGLAND SUN
AND THEN SLOWLY TRACKING S IN THE NEW WK. QUSTN WL BE WHETHER THIS
WL BE STRONG ENUF TO GENERATE ANY PCPN - THIS IS NOT A NRML MID
JUL PATTERN. FOR NOW WL STAY W/ CHC POPS FOR SUN-MON. WE ARE
CLIMATOLOGICALLY IN THE WARMEST PD OF THE YR...W/ HIGHS IN THE
U80S. THIS PATTERN DOES NOT MAKE ME WANT TO FCST TEMPS ANY WARMER
THAN THAT.
WE`VE RCVD CALLS ABT CHANTAL. AT THIS MOMENT ON STLT IT LOOKS
XTRMLY DISORGANIZED. AND W/ CD FNT MOVING S OF US IT APPEARS THAT
IT`LL BE DIFFICULT FOR REMNANTS TO GET THIS FAR N. REGARDLESS ANY
EFFECTS FM THIS STORM..IF THERE ARE ANY...ARE MANY DAYS AWAY FM
AFFECTING THE MID ALTC.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
MVFR/IFR CONDITIONS POSSIBLE IN HEAVY RAIN AND THUNDERSTORMS TODAY.
ACTIVE WEATHER PATTERN RESTARTS FOR THE REGION TODAY AS A
TROUGH APPROACHES FROM THE WEST...THUNDERSTORMS LIKELY TODAY..IFR
CONDS IN HEAVIEST ACTIVITY. SWLY AROUND 10 KT WITH GUSTS TO 20 KT
INTO THIS EVENING.
MAJORITY OF XTND PD IS XPCTD TO FEATURE VFR CONDS.
&&
.MARINE...
LOWER SRN MD PORTION OF THE BAY IN SCA THROUGH MIDDAY. THIS IS
CURRENTLY VERIFYING...MAY NEED TO BE EXPANDED NORTH BY THE LATE
MORNING. ALL WATERS IN SCA FOR THE AFTERNOON/EVENING...THEN MAIN
PORTIONS OF THE BAY OVERNIGHT. THUNDERSTORMS THIS AFTERNOON MAY
REQUIRE SOME SPECIAL MARINE WARNINGS FOR WIND GUSTS IN EXCESS OF 34
KT.
GUSTS TO NEAR 20 KT MAY BE PSBL ON THE LWR BAY/TIDAL PTMC E OF
COBB ISLAND THU. PRES GRAD WL BE LGT MAJORITY OF XTND...AS OF NOW
NO SCA XPCTD FOR THE WKND.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 4 AM EDT
THURSDAY FOR ANZ530>532-537>541.
SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO MIDNIGHT EDT
TONIGHT FOR ANZ535-536-542.
SMALL CRAFT ADVISORY UNTIL 4 AM EDT THURSDAY FOR ANZ533-534-
543.
SMALL CRAFT ADVISORY FROM 8 AM TO 2 PM EDT THURSDAY FOR ANZ534-
537-543.
&&
$$
UPDATE...HAS
PREVIOUS...BAJ/ADW
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1245 PM CDT WED JUL 10 2013
.UPDATE...
ISSUED AT 1245 PM CDT WED JUL 10 2013
LATEST RAP/HRRR SEEM TO HAVE PICKED UP ON CONVECTIVE CLUSTER
ACROSS SOUTHERN MANITOBA AND DROP IT SOUTHEASTWARD THROUGH THE
AFTERNOON. BASED ON THESE SOLUTIONS...REFINED POPS TO CONFINE
THEM MAINLY ALONG AND NORTH OF THE HIGHWAY 2 CORRIDOR THROUGH
THE EARLY EVENING. REST OF THE FORECAST IN GOOD SHAPE AT THIS
TIME WITH NO CHANGES PLANNED.
UPDATE ISSUED AT 1030 AM CDT WED JUL 10 2013
MAIN CONCERNS ARE PRECIPITATION CHANCES THIS AFTERNOON AND WIND
SPEEDS AND RESULTING WAVE HEIGHTS ALONG THE SOUTH SHORE OF LAKE
SUPERIOR. CANADIAN RADARS SHOWING AN AREA OF SHOWERS AND ISOLATED
THUNDERSTORMS ACROSS SOUTHERN MANITOBA IN RESPONSE TO A WELL-
DEFINED SHORT WAVE VISIBLE IN THE LATEST WATER VAPOR LOOP. NO
MODELS ARE CAPTURING THIS FEATURE...BUT BASED ON LATEST TRENDS...
WILL ADD SOME CHANCE POPS ALONG THE CANADIAN BORDER THIS
AFTERNOON.
WITH NORTHWEST SURFACE FLOW...WILL NEED TO WATCH WIND SPEEDS ALONG
THE SOUTH SHORE OF LAKE SUPERIOR...ESPECIALLY ACROSS THE APOSTLE
ISLANDS. MODEL SOUNDINGS SHOW A DEEP AFTERNOON BOUNDARY LAYER WITH
UP TO 30 KTS TO MIX TO THE SURFACE...BUT SURFACE BASED GUIDANCE
SHOWS WIND SPEEDS MAXING OUT AROUND 15 KTS BY MID-AFTERNOON. WILL
HOLD OFF ON ISSUANCE OF A SMALL CRAFT ADVISORY...BUT MAY NEED TO
RE-EVALUATE THIS AFTERNOON.
ADJUSTED SKY GRIDS TO ACCOUNT FOR ROBUST CU FIELD ACROSS THE MN
ARROWHEAD. REST OF THE FORECAST IS IN GOOD SHAPE WITH NO MAJOR
CHANGES AT THIS TIME.
&&
.SHORT TERM.../NOW - TONIGHT/
AT 300AM/0800Z...THERE WAS A MID/UPPER LEVEL TROUGH CENTERED FROM
WESTERN ONTARIO TO THE EASTERN FORECAST AREA. SURFACE HIGH
PRESSURE WAS CENTERED IN THE WESTERN DAKOTAS. MUCH OF THE
NORTHLAND HAD CLEAR SKIES...EXCEPT FOR PARTS OF THE EASTERN AND
NORTHERN FORECAST AREA. MORE EXTENSIVE CLOUD COVER WAS LOCATED
FARTHER NORTH AND EAST OF THE NORTHLAND...WHILE MUCH OF THE
NORTHERN PLAINS HAD CLEAR SKIES. MUCH OF THE NORTHLAND HAD 5 TO 10
MPH WNW TO NW WINDS...WHICH WAS HELPING TO KEEP THE TEMPERATURES
UP. THE TEMPERATURES RANGED FROM THE MID 50S TO MID 60S.
TODAY...THE SURFACE HIGH PRESSURE IN THE NORTHERN PLAINS WILL
BEGIN TO SHIFT EAST INTO THE UPPER MIDWEST. THE NORTHLAND CAN
EXPECT RELATIVELY SUNNY AND WEATHER EARLY THIS MORNING.
HOWEVER...SCATTERED CUMULUS WILL LIKELY DEVELOP BY THE AFTERNOON
SINCE THE MODEL SOUNDINGS INDICATE RELATIVELY LOW CONVECTIVE
TEMPERATURES IN THE BREEZY NW FLOW. THE LATEST HRRR RUNS ARE
PICKING UP ON THE SCATTERED CUMULUS. ALSO...THE NAM12 AND GFS ARE
SHOWING A SHORTWAVE MOVING INTO THE WESTERN FORECAST AREA THIS
AFTERNOON...AND THE NAM12/DLHWRF/WRF MODELS ARE HINTING AT A LOW
THREAT OF SHOWERS AND STORMS WITH THIS SHORTWAVE. I ADDED ISOLATED
STORMS ACROSS THE WESTERN FORECAST AREA FOR THIS AFTERNOON AND
EARLY EVENING. HIGH TEMPERATURES SHOULD BE IN THE MID 70S TO NEAR
80 DEGREES.
TONIGHT...THE RELATIVELY DRY CONDITIONS THAT WILL DEVELOP THIS
AFTERNOON DUE TO THE MIXING IN THE NW FLOW...COMBINED WITH THE
WEAKENING WINDS TONIGHT AS HIGH PRESSURE MOVES INTO THE UPPER
MIDWEST...WILL HELP FOR DECENT RADIATIONAL COOLING TONIGHT. I
LOWERED THE LOW TEMPERATURE FORECAST BY A COUPLE TO FEW DEGREES.
THE LOW TEMPERATURES SHOULD AROUND 50 DEGREES TO THE MID 50S...BUT
I COULD SEE ISOLATED AREAS GETTING DOWN TO THE MID 40S DEPENDING
ON AFTERNOON DEW POINT TEMPERATURES. DESPITE THE CLEAR SKIES AND
NEGLIGIBLE WINDS THAT WILL DEVELOP...I THINK THE THREAT OF FOG IS
LOW BECAUSE OF THE RELATIVELY DRY CONDITIONS THAT WILL DEVELOP IN
THE AFTERNOON. IF THERE IS ANY FOG...IT WILL PROBABLY DEVELOP VERY
LATE IN THE NIGHT AND BE ISOLATED.
.LONG TERM.../THURSDAY - TUESDAY/
FOCUS IN EXTENDED ON RETURN OF UPPER LEVEL RIDGE AND SRLY FLOW
WITH INCREASING H85 TEMPS THURSDAY NIGHT/FRIDAY...THEN STALLED
BAROCLINIC ZONE THAT WILL BECOME FOCUS FOR RAIN/TSTORMS THROUGH
THE WEEKEND. LONG RANGE MODELS CONTINUE TO STRUGGLE WITH THE
PLACEMENT OF THE STALLED FRONT AND ASSOCIATED BAND OF
PRECIPITATION. HAVE POPS MOVING INTO NW ZONES FRIDAY NIGHT...WITH
WIDESPREAD HIGH CHANCE/LIKELY POPS FOR SHOWERS AND TSTORMS ACROSS
THE CWA SATURDAY/SUNDAY. LATEST NAM DEPICTS VERY HIGH PWATS
APPROACHING 2 INCHES SPREADS OVER THE NORTHLAND THROUGH FRIDAY
EVENING. IF THE BOUNDARY DOES STALL OVER A PORTION OF THE FORECAST
AREA...THE ABUNDANT MOISTURE AND PROLONGED PERIOD OF RAIN COULD
LEAD TO LOCALIZED FLOODING CONCERNS. THE MAIN THREAT FOR HEAVY
RAIN AT THIS TIME LOOKS TO BE FRIDAY NIGHT THROUGH SATURDAY NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1245 PM CDT WED JUL 10 2013
VFR CONDITIONS EXPECTED TO CONTINUE ACROSS THE NORTHLAND. DID
INTRODUCE VCSH AT INL AND BRD THIS EVENING WITH SMALL CONVECTIVE
CLUSTER INDUCED BY SHORT WAVE ENERGY SEEN IN THE WATER VAPOR IMAGERY
CURRENTLY NEAR WINNIPEG. CURRENT THINKING IS THAT AREAL COVERAGE TO
REMAIN WEST OF DLH...HIB AND HYR. SOME FG/BR POTENTIAL EXISTS
OVERNIGHT BUT HAVE LEFT OUT OF TAFS FOR NOW.
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR LSZ140-141.
&&
$$
UPDATE...ROGERS
SHORT TERM...GROCHOCINSKI
LONG TERM....GRANING
AVIATION...KAISER
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1030 AM CDT WED JUL 10 2013
.UPDATE...
ISSUED AT 1030 AM CDT WED JUL 10 2013
MAIN CONCERNS ARE PRECIPITATION CHANCES THIS AFTERNOON AND WIND
SPEEDS AND RESULTING WAVE HEIGHTS ALONG THE SOUTH SHORE OF LAKE
SUPERIOR. CANADIAN RADARS SHOWING AN AREA OF SHOWERS AND ISOLATED
THUNDERSTORMS ACROSS SOUTHERN MANITOBA IN RESPONSE TO A WELL-
DEFINED SHORT WAVE VISIBLE IN THE LATEST WATER VAPOR LOOP. NO
MODELS ARE CAPTURING THIS FEATURE...BUT BASED ON LATEST TRENDS...
WILL ADD SOME CHANCE POPS ALONG THE CANADIAN BORDER THIS
AFTERNOON.
WITH NORTHWEST SURFACE FLOW...WILL NEED TO WATCH WIND SPEEDS ALONG
THE SOUTH SHORE OF LAKE SUPERIOR...ESPECIALLY ACROSS THE APOSTLE
ISLANDS. MODEL SOUNDINGS SHOW A DEEP AFTERNOON BOUNDARY LAYER WITH
UP TO 30 KTS TO MIX TO THE SURFACE...BUT SURFACE BASED GUIDANCE
SHOWS WIND SPEEDS MAXING OUT AROUND 15 KTS BY MID-AFTERNOON. WILL
HOLD OFF ON ISSUANCE OF A SMALL CRAFT ADVISORY...BUT MAY NEED TO
RE-EVALUATE THIS AFTERNOON.
ADJUSTED SKY GRIDS TO ACCOUNT FOR ROBUST CU FIELD ACROSS THE MN
ARROWHEAD. REST OF THE FORECAST IS IN GOOD SHAPE WITH NO MAJOR
CHANGES AT THIS TIME.
&&
.SHORT TERM.../NOW - TONIGHT/
AT 300AM/0800Z...THERE WAS A MID/UPPER LEVEL TROUGH CENTERED FROM
WESTERN ONTARIO TO THE EASTERN FORECAST AREA. SURFACE HIGH
PRESSURE WAS CENTERED IN THE WESTERN DAKOTAS. MUCH OF THE
NORTHLAND HAD CLEAR SKIES...EXCEPT FOR PARTS OF THE EASTERN AND
NORTHERN FORECAST AREA. MORE EXTENSIVE CLOUD COVER WAS LOCATED
FARTHER NORTH AND EAST OF THE NORTHLAND...WHILE MUCH OF THE
NORTHERN PLAINS HAD CLEAR SKIES. MUCH OF THE NORTHLAND HAD 5 TO 10
MPH WNW TO NW WINDS...WHICH WAS HELPING TO KEEP THE TEMPERATURES
UP. THE TEMPERATURES RANGED FROM THE MID 50S TO MID 60S.
TODAY...THE SURFACE HIGH PRESSURE IN THE NORTHERN PLAINS WILL
BEGIN TO SHIFT EAST INTO THE UPPER MIDWEST. THE NORTHLAND CAN
EXPECT RELATIVELY SUNNY AND WEATHER EARLY THIS MORNING.
HOWEVER...SCATTERED CUMULUS WILL LIKELY DEVELOP BY THE AFTERNOON
SINCE THE MODEL SOUNDINGS INDICATE RELATIVELY LOW CONVECTIVE
TEMPERATURES IN THE BREEZY NW FLOW. THE LATEST HRRR RUNS ARE
PICKING UP ON THE SCATTERED CUMULUS. ALSO...THE NAM12 AND GFS ARE
SHOWING A SHORTWAVE MOVING INTO THE WESTERN FORECAST AREA THIS
AFTERNOON...AND THE NAM12/DLHWRF/WRF MODELS ARE HINTING AT A LOW
THREAT OF SHOWERS AND STORMS WITH THIS SHORTWAVE. I ADDED ISOLATED
STORMS ACROSS THE WESTERN FORECAST AREA FOR THIS AFTERNOON AND
EARLY EVENING. HIGH TEMPERATURES SHOULD BE IN THE MID 70S TO NEAR
80 DEGREES.
TONIGHT...THE RELATIVELY DRY CONDITIONS THAT WILL DEVELOP THIS
AFTERNOON DUE TO THE MIXING IN THE NW FLOW...COMBINED WITH THE
WEAKENING WINDS TONIGHT AS HIGH PRESSURE MOVES INTO THE UPPER
MIDWEST...WILL HELP FOR DECENT RADIATIONAL COOLING TONIGHT. I
LOWERED THE LOW TEMPERATURE FORECAST BY A COUPLE TO FEW DEGREES.
THE LOW TEMPERATURES SHOULD AROUND 50 DEGREES TO THE MID 50S...BUT
I COULD SEE ISOLATED AREAS GETTING DOWN TO THE MID 40S DEPENDING
ON AFTERNOON DEW POINT TEMPERATURES. DESPITE THE CLEAR SKIES AND
NEGLIGIBLE WINDS THAT WILL DEVELOP...I THINK THE THREAT OF FOG IS
LOW BECAUSE OF THE RELATIVELY DRY CONDITIONS THAT WILL DEVELOP IN
THE AFTERNOON. IF THERE IS ANY FOG...IT WILL PROBABLY DEVELOP VERY
LATE IN THE NIGHT AND BE ISOLATED.
.LONG TERM.../THURSDAY - TUESDAY/
FOCUS IN EXTENDED ON RETURN OF UPPER LEVEL RIDGE AND SRLY FLOW
WITH INCREASING H85 TEMPS THURSDAY NIGHT/FRIDAY...THEN STALLED
BAROCLINIC ZONE THAT WILL BECOME FOCUS FOR RAIN/TSTORMS THROUGH
THE WEEKEND. LONG RANGE MODELS CONTINUE TO STRUGGLE WITH THE
PLACEMENT OF THE STALLED FRONT AND ASSOCIATED BAND OF
PRECIPITATION. HAVE POPS MOVING INTO NW ZONES FRIDAY NIGHT...WITH
WIDESPREAD HIGH CHANCE/LIKELY POPS FOR SHOWERS AND TSTORMS ACROSS
THE CWA SATURDAY/SUNDAY. LATEST NAM DEPICTS VERY HIGH PWATS
APPROACHING 2 INCHES SPREADS OVER THE NORTHLAND THROUGH FRIDAY
EVENING. IF THE BOUNDARY DOES STALL OVER A PORTION OF THE FORECAST
AREA...THE ABUNDANT MOISTURE AND PROLONGED PERIOD OF RAIN COULD
LEAD TO LOCALIZED FLOODING CONCERNS. THE MAIN THREAT FOR HEAVY
RAIN AT THIS TIME LOOKS TO BE FRIDAY NIGHT THROUGH SATURDAY NIGHT.
&&
.AVIATION.../06Z TAF ISSUANCE/
VFR CONDITIONS HAVE RETURNED TO THE TERMINALS THIS EVENING AFTER A
COLD FRONT MOVED THROUGH THE AREA. DRIER AIR FILTERING INTO THE
AREA FROM THE NORTHWEST IS EXPECTED TO KEEP FOG FROM FORMING AT
MOST TERMINALS...BUT KHYR MAY STILL FORM SOME...DUE TO THE LATER
TIMING OF THE DRIER AIR. IN THE 14Z- 16Z TIME RANGE WEDNESDAY
NORTHWEST WINDS ARE EXPECTED TO INCREASE TO 10-15KTS AND GUST TO
20KTS MOST LOCATIONS...BUT LIGHTER AT KHYR. WINDS TO DIMINISH
AGAIN AFTER 23Z. VFR CONDITIONS EXPECTED 14Z THROUGH END OF TAF
PERIOD.
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR LSZ140-141.
&&
$$
UPDATE...ROGERS
SHORT TERM...GROCHOCINSKI
LONG TERM....GRANING
AVIATION...GRANING
AREA FORECAST DISCUSSION
NWS DULUTH MN
310 AM CDT WED JUL 10 2013
.SHORT TERM.../NOW - TONIGHT/
AT 300AM/0800Z...THERE WAS A MID/UPPER LEVEL TROUGH CENTERED FROM
WESTERN ONTARIO TO THE EASTERN FORECAST AREA. SURFACE HIGH
PRESSURE WAS CENTERED IN THE WESTERN DAKOTAS. MUCH OF THE
NORTHLAND HAD CLEAR SKIES...EXCEPT FOR PARTS OF THE EASTERN AND
NORTHERN FORECAST AREA. MORE EXTENSIVE CLOUD COVER WAS LOCATED
FARTHER NORTH AND EAST OF THE NORTHLAND...WHILE MUCH OF THE
NORTHERN PLAINS HAD CLEAR SKIES. MUCH OF THE NORTHLAND HAD 5 TO 10
MPH WNW TO NW WINDS...WHICH WAS HELPING TO KEEP THE TEMPERATURES
UP. THE TEMPERATURES RANGED FROM THE MID 50S TO MID 60S.
TODAY...THE SURFACE HIGH PRESSURE IN THE NORTHERN PLAINS WILL
BEGIN TO SHIFT EAST INTO THE UPPER MIDWEST. THE NORTHLAND CAN
EXPECT RELATIVELY SUNNY AND WEATHER EARLY THIS MORNING.
HOWEVER...SCATTERED CUMULUS WILL LIKELY DEVELOP BY THE AFTERNOON
SINCE THE MODEL SOUNDINGS INDICATE RELATIVELY LOW CONVECTIVE
TEMPERATURES IN THE BREEZY NW FLOW. THE LATEST HRRR RUNS ARE
PICKING UP ON THE SCATTERED CUMULUS. ALSO...THE NAM12 AND GFS ARE
SHOWING A SHORTWAVE MOVING INTO THE WESTERN FORECAST AREA THIS
AFTERNOON...AND THE NAM12/DLHWRF/WRF MODELS ARE HINTING AT A LOW
THREAT OF SHOWERS AND STORMS WITH THIS SHORTWAVE. I ADDED ISOLATED
STORMS ACROSS THE WESTERN FORECAST AREA FOR THIS AFTERNOON AND
EARLY EVENING. HIGH TEMPERATURES SHOULD BE IN THE MID 70S TO NEAR
80 DEGREES.
TONIGHT...THE RELATIVELY DRY CONDITIONS THAT WILL DEVELOP THIS
AFTERNOON DUE TO THE MIXING IN THE NW FLOW...COMBINED WITH THE
WEAKENING WINDS TONIGHT AS HIGH PRESSURE MOVES INTO THE UPPER
MIDWEST...WILL HELP FOR DECENT RADIATIONAL COOLING TONIGHT. I
LOWERED THE LOW TEMPERATURE FORECAST BY A COUPLE TO FEW DEGREES.
THE LOW TEMPERATURES SHOULD AROUND 50 DEGREES TO THE MID 50S...BUT
I COULD SEE ISOLATED AREAS GETTING DOWN TO THE MID 40S DEPENDING
ON AFTERNOON DEW POINT TEMPERATURES. DESPITE THE CLEAR SKIES AND
NEGLIGIBLE WINDS THAT WILL DEVELOP...I THINK THE THREAT OF FOG IS
LOW BECAUSE OF THE RELATIVELY DRY CONDITIONS THAT WILL DEVELOP IN
THE AFTERNOON. IF THERE IS ANY FOG...IT WILL PROBABLY DEVELOP VERY
LATE IN THE NIGHT AND BE ISOLATED.
.LONG TERM.../THURSDAY - TUESDAY/
FOCUS IN EXTENDED ON RETURN OF UPPER LEVEL RIDGE AND SRLY FLOW
WITH INCREASING H85 TEMPS THURSDAY NIGHT/FRIDAY...THEN STALLED
BAROCLINIC ZONE THAT WILL BECOME FOCUS FOR RAIN/TSTORMS THROUGH
THE WEEKEND. LONG RANGE MODELS CONTINUE TO STRUGGLE WITH THE
PLACEMENT OF THE STALLED FRONT AND ASSOCIATED BAND OF
PRECIPITATION. HAVE POPS MOVING INTO NW ZONES FRIDAY NIGHT...WITH
WIDESPREAD HIGH CHANCE/LIKELY POPS FOR SHOWERS AND TSTORMS ACROSS
THE CWA SATURDAY/SUNDAY. LATEST NAM DEPICTS VERY HIGH PWATS
APPROACHING 2 INCHES SPREADS OVER THE NORTHLAND THROUGH FRIDAY
EVENING. IF THE BOUNDARY DOES STALL OVER A PORTION OF THE FORECAST
AREA...THE ABUNDANT MOISTURE AND PROLONGED PERIOD OF RAIN COULD
LEAD TO LOCALIZED FLOODING CONCERNS. THE MAIN THREAT FOR HEAVY
RAIN AT THIS TIME LOOKS TO BE FRIDAY NIGHT THROUGH SATURDAY NIGHT.
&&
.AVIATION.../06Z TAF ISSUANCE/
VFR CONDITIONS HAVE RETURNED TO THE TERMINALS THIS EVENING AFTER A
COLD FRONT MOVED THROUGH THE AREA. DRIER AIR FILTERING INTO THE
AREA FROM THE NORTHWEST IS EXPECTED TO KEEP FOG FROM FORMING AT
MOST TERMINALS...BUT KHYR MAY STILL FORM SOME...DUE TO THE LATER
TIMING OF THE DRIER AIR. IN THE 14Z- 16Z TIME RANGE WEDNESDAY
NORTHWEST WINDS ARE EXPECTED TO INCREASE TO 10-15KTS AND GUST TO
20KTS MOST LOCATIONS...BUT LIGHTER AT KHYR. WINDS TO DIMINISH
AGAIN AFTER 23Z. VFR CONDITIONS EXPECTED 14Z THROUGH END OF TAF
PERIOD.
&&
.POINT TEMPS/POPS...
DLH 76 54 79 58 / 10 10 0 0
INL 77 51 82 62 / 20 10 0 10
BRD 79 55 82 64 / 20 20 0 0
HYR 80 50 81 56 / 10 0 0 0
ASX 76 51 79 56 / 0 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR LSZ140-141.
&&
$$
SHORT TERM...GROCHOCINSKI
LONG TERM....GRANING
AVIATION...GRANING
AREA FORECAST DISCUSSION
NWS DULUTH MN
1255 AM CDT WED JUL 10 2013
.AVIATION...06Z TAFS...
VFR CONDITIONS HAVE RETURNED TO THE TERMINALS THIS EVENING AFTER
A COLD FRONT MOVED THROUGH THE AREA. DRIER AIR FILTERING INTO THE
AREA FROM THE NORTHWEST IS EXPECTED TO KEEP FOG FROM FORMING AT
MOST TERMINALS...BUT KHYR MAY STILL FORM SOME...DUE TO THE LATER
TIMING OF THE DRIER AIR. IN THE 14Z- 16Z TIME RANGE WEDNESDAY
NORTHWEST WINDS ARE EXPECTED TO INCREASE TO 10-15KTS AND GUST TO
20KTS MOST LOCATIONS...BUT LIGHTER AT KHYR. WINDS TO DIMINISH
AGAIN AFTER 23Z. VFR CONDITIONS EXPECTED 14Z THROUGH END OF TAF
PERIOD.
&&
.PREV DISCUSSION... /ISSUED 649 PM CDT TUE JUL 9 2013/
UPDATE...
HAVE SENT OUT SOME UPDATES TO REFINE PRECIPITATION AND CLOUD TRENDS
THIS EVENING. THE TROUGH AXIS SWEEPING ACROSS THE AREA NOW THAT IS
ASSOCIATED WITH SOME SHOWERS/ISOLATED TSRA ARE VERY LIKELY THE
TAIL END OF PRECIPITATION FOR THE EVENING...THOUGH CANNOT RULE OUT
A FEW ISOLATED SHOWERS AS CAN BE SEEN BACK AROUND WASKISH. THIS
TROUGH AXIS IS ALSO THE LEADING EDGE OF THE DRY AIR...WHERE
DEWPOINTS GO FROM THE MID 60S AROUND HIBBING...DROPPING TO THE MID
50S BY BAUDETTE.
PREV DISCUSSION... /ISSUED 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.
&&
.POINT TEMPS/POPS...
DLH 77 56 79 58 / 0 0 0 0
INL 76 55 82 61 / 10 0 0 10
BRD 78 55 82 62 / 0 0 0 10
HYR 78 52 81 58 / 0 0 0 0
ASX 76 51 79 57 / 0 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
AVIATION...LE
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
1201 PM CDT WED JUL 10 2013
.SHORT TERM...(THROUGH LATE TONIGHT)
ISSUED AT 1153 AM CDT WED JUL 10 2013
THE TRAILING MCS WHICH DEVELOPED EARLIER THIS MORNING IN THE WAKE
OF THE OVERNIGHT MCS HAS NEARLY DISSIPATED. THIS SYSTEM APPEARS TO
HAVE BEEN LARGELY DRIVEN BY A WESTERLY LLJ PROVIDING MESOSCALE
LIFT ALONG THE WESTERN PERIPHERY OF THE INTIAL SYSTEMS OUTFLOW
BOUNDARY AND WAS ALSO AIDED BY A MID LEVEL SHORT WAVE/CONVECTIVE
VORT MAX. THIS MID LEVEL WAVE EXTENDED FROM EASTERN IL INTO SE MO
AT 16Z AND WILL CONTINUE TO MOVE SEWD WITHIN THE NW FLOW ALOFT.
THE QUESTION REMAINS IF THERE WILL BE ANY ADDITIONAL DEVELOPMENT
WITH THE COLD FRONT...WHICH IS NOW LOCATED FROM AROUND PITTSFIELD
TO COLUMBIA. THERE IS SOME WEAK SUBSIDENCE IN THE WAKE OF THE MID
LEVEL WAVE AND CLOUDS/PRECIPITATION HAVE INHIBITED HEATING THIS
MORNING. AS CLOUDS THIN THIS AFTERNOON WE WILL GET SOME HEATING
AND DESTABILIZATION...BUT CURRENT INDICATIONS ARE THAT TEMPS AND
INSTABILITY WILL BE LOWER THAN PREVIOUSLY ANTICIPATED AND COVERAGE
OF ANY STORMS WHICH MANAGE TO DEVELOP ALONG THE COLD FRONT OR
REMNANT BOUNDARY SHOULD BE LOW - ISOLATED TO WIDELY SCATTERED.
GLASS
.LONG TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 311 AM CDT WED JUL 10 2013
TONIGHT...SCT TSRA ALONG A CDFNT SHOULD DIMINISH WITH TIME THIS
EVENING AS THE BDRY MOVES THROUGH THE AREA AND EVENTUALLY STALLS IN
AR.
THU THROUGH SAT...A COOLER AND DRIER AIR MASS WILL SPREAD ACROSS
MO/IL BEHIND THE AFOREMENTIONED CDFNT...BRINGING A SHORT BREAK FROM
THE RECENT HOT AND HUMID CONDITIONS. COOLER AND DRIER WX WILL
PERSIST UNTIL THE SFC HIGH OVER IA/WI/IL SHIFTS EWD AND THE STRONG
UPPER RIDGE OVER THE SWRN CONUS BUILDS INTO THE CENTRAL PLAINS.
SUN THROUGH TUE...A 594+ DAM H5 PRESSURE CENTER IS FCST TO BE
LOCATED OVER THE CENTER OF THE COUNTRY BY EARLY NEXT WEEK. THIS WILL
BRING A RETURN OF HOT WEATHER TO THE AREA WITH LIMITED OPPORTUNITIES
FOR PCPN. MODELS ARE FCSTG A BROAD AREA OF FAIRLY WEAK VORTICITY TO
BREAK OFF FROM THE ERN CONUS TROF AND THEN MOVE WWD ACROSS THE SRN
CONUS ON THE SOUTH SIDE OF THE HIGH. DEPENDING ON THE DETAILS...THIS
FEATURE COULD PROVIDE JUST ENOUGH SUPPORT FOR ISO-SCT PCPN ACROSS
THE SRN CWA. AS HAS BEEN THE CASE FOR THE LAST SEVERAL DAYS...MODELS
CONTINUE TO SHOW A CLOSED LOW DVLPG SOMEWHERE ALONG THE
APPALACHIANS...BUT THERE HAS BEEN LITTLE RUN TO RUN CONSISTENCY SO
FAR.
KANOFSKY
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 658 AM CDT WED JUL 10 2013
COVERAGE OF ELEVATED CONVECTION HAS RAPIDLY INCREASED
OVER THE LAST FEW HOURS...BUT STILL EXPECTING THIS ACTIVITY TO
SHIFT TO THE SE DURING THE MORNING. APPROXIMATE BACK EDGE OF THE
PRECIP IS NEAR A BOONEVILLE...UIN LINE...SO WHILE COU WILL BE OUT
OF THE THUNDER THREAT SHORTLY STL AREA TAFS WILL REMAIN WITH
TEMPOS FOR TSRA UNTIL LATE MORNING. PREVAILING CONDITIONS WILL BE
VFR CIGS AOA 5KFT...BUT WITH THE HIT AND MISS STRONG CORES VSBYS
WILL CERTAINLY DROP TO IFR...WITH CIGS AT LEAST DIPPING INTO THE
MVFR RANGE. WILL BE WATCHING RADAR TRENDS TO DETERMINE IF
AMENDMENTS WILL BE NECESSARY FOR THESE LOWER CONDITIONS. STILL
UNCERTAIN HOW ANY ADDITIONAL ACTIVITY WILL EVOLVE BY THIS
AFTERNOON...BUT IN SPITE OF WEAKENING CONVERGENCE ALONG
FRONT AND WITH BOUNDARY FROM THIS MORNINGS ACTIVITY SETTING UP S
OF OUR CWA...THINK THAT REDEVELOPMENT MAY STILL OCCUR NEAR THE
SYNOPTIC FRONT DUE TO RESIDUAL INSTABILITY AND WEAK UPPER LEVEL
DYNAMICS DIPPING INTO THE AREA. SO...FOLLOWING THE LEAD OF THE
LATEST HRRR DATA WILL REINTRODUCE VCTS IN STL FOR A BRIEF PERIOD
EARLY THIS AFTERNOON...BEFORE FROPA PUSHES ACTIVITY S INTO SE MO/S IL.
TRANQUIL CONDITIONS SHOULD PREVAIL THROUGHOUT THE AREA THIS
EVENING...WITH CLEAR SKIES AND NORTH WINDS AOB 10 KTS.
SPECIFICS FOR KSTL...
BASED ON ABOVE REASONING WILL BE CARRYING TEMPO TSRA THROUGH 15Z
WITH VFR CIGS AND MVFR VSBYS....BUT AS MENTIONED WILL BE WATCHING
RADAR TRENDS TO DETERMINE IF MORE INTENSE CORES WILL IMPACT THE
TERMINAL AREA. PRECIP THREAT SHOULD BRIEFLY LULL BEFORE
REINTRODUCTION OF TSRA AS FRONTAL BOUNDARY MOVES THROUGH IN THE
18-20Z TIME FRAME...BUT AFTER 20Z FRONT SHOULD BE FAR ENOUGH SOUTH
THAT THREAT WILL END. LATE AFTERNOON AND INTO THE EVENING SHOULD
GENERALLY BE CLEAR/VFR...WITH LIGHT NORTH WINDS 5-10KTS.
TRUETT
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
721 AM CDT WED JUL 10 2013
.UPDATE...
ISSUED AT 633 AM CDT WED JUL 10 2013
UPDATED GRIDS AND PRODUCTS TO RAISE POPS OVER AREAS WHERE
CONVECTION HAS BLOSSOMED THIS MORNING.
KANOFSKY
&&
.SHORT TERM...(THROUGH LATE THIS AFTERNOON)
ISSUED AT 311 AM CDT WED JUL 10 2013
CONVECTION TRENDS OVERNIGHT HAVE BEEN A BIT INCOHERENT TO SAY THE
LEAST...BUT REGIONAL RADAR IMAGERY OVER THE LAST 90 MINUTES SEEM TO
SUGGEST THAT VEERING LOW LEVEL JET AND ASSOCIATED WARM ADVECTION
FROM W MO INTO S IL WILL BE THE MAIN DRIVING MECHANISM FOR
THUNDERSTORMS EARLY TODAY. OVER THE LAST 30 MINUTES THERE HAS BEEN
A RAPID INCREASE IN COVERAGE OVER N OZARKS...AND IT APPEARS THIS IS
TRYING TO "CONNECT" WITH SPOTTIER STORMS THAT DEVELOPED NW OF STL
SHORTLY AFTER 06Z. THIS ENTIRE AREA SHOULD SHIFT SOUTH WITH THE
VEERING LOW LEVEL JET AS THE MORNING PROGRESSES. MEANWHILE...
LINGERING CONVECTION OVER NW MO/SE NE CERTAINLY INDICATES THAT SOME
THUNDERSTORM THREAT WILL ALSO CONTINUE NEAR THE APPROACHING COLD
FRONT AT LEAST FOR A FEW HOURS THIS MORNING.
THE EXACT EVOLUTION OF THE PRECIPITATION THIS MORNING WILL HAVE A
MAJOR IMPACT ON TIMING AND LOCATION OF ADDITIONAL THUNDERSTORM
ACTIVITY AND SEVERE WEATHER POTENTIAL THIS AFTERNOON....BUT FOR NOW
HAVE MAINTAINED HIGH CHANCE POPS FOR AREAS SE OF STL. AM A BIT
CONCERNED THAT THIS MORNINGS ACTIVITY MAY SET UP THE PRIMARY FOCUS
FOR ADDITIONAL CONVECTION OVER FAR S SECTIONS OF OUR CWA...AND IN
ADDITION STRONG W COMPONENT TO SURFACE/LOW LEVEL FLOW S OF THE COLD
FRONT SHOULD CERTAINLY LIMIT CONVERGENCE ALONG THE ACTUAL FRONTAL
BOUNDARY. HOWEVER...AMS WILL CERTAINLY REMAIN QUITE UNSTABLE WITH
MUCAPES OF 3000-4000 J/KG...AND ALL SYNOPTIC MODELS ARE SUGGESTING
NW FLOW WILL ALLOW SUBTLE SHORTWAVE ENERGY TO PROPAGATE INTO THE
AREA...SO WILL NOT TOTALLY GIVE UP PRECIP CHANCES ALONG THE ACTUAL
COLD FRONT EVEN IF MORE SIGNIFICANT BOUNDARY ENDS UP WELL SOUTH.
NO MAJOR CHANGES TO GOING TEMPS...MU80S IN OUR NW COUNTIES TO THE
LM90S IN OUR SE...WHERE HEAT INDEX VALUES WILL ONCE AGAIN PUSH THE
CENTURY MARK. HOWEVER...CLOUDS AND PRECIP SHOULD KEEP HI FROM
REACHING ADVISORY CRITERIA.
TRUETT
.LONG TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 311 AM CDT WED JUL 10 2013
TONIGHT...SCT TSRA ALONG A CDFNT SHOULD DIMINISH WITH TIME THIS
EVENING AS THE BDRY MOVES THROUGH THE AREA AND EVENTUALLY STALLS IN
AR.
THU THROUGH SAT...A COOLER AND DRIER AIR MASS WILL SPREAD ACROSS
MO/IL BEHIND THE AFOREMENTIONED CDFNT...BRINGING A SHORT BREAK FROM
THE RECENT HOT AND HUMID CONDITIONS. COOLER AND DRIER WX WILL
PERSIST UNTIL THE SFC HIGH OVER IA/WI/IL SHIFTS EWD AND THE STRONG
UPPER RIDGE OVER THE SWRN CONUS BUILDS INTO THE CENTRAL PLAINS.
SUN THROUGH TUE...A 594+ DAM H5 PRESSURE CENTER IS FCST TO BE
LOCATED OVER THE CENTER OF THE COUNTRY BY EARLY NEXT WEEK. THIS WILL
BRING A RETURN OF HOT WEATHER TO THE AREA WITH LIMITED OPPORTUNITIES
FOR PCPN. MODELS ARE FCSTG A BROAD AREA OF FAIRLY WEAK VORTICITY TO
BREAK OFF FROM THE ERN CONUS TROF AND THEN MOVE WWD ACROSS THE SRN
CONUS ON THE SOUTH SIDE OF THE HIGH. DEPENDING ON THE DETAILS...THIS
FEATURE COULD PROVIDE JUST ENOUGH SUPPORT FOR ISO-SCT PCPN ACROSS
THE SRN CWA. AS HAS BEEN THE CASE FOR THE LAST SEVERAL DAYS...MODELS
CONTINUE TO SHOW A CLOSED LOW DVLPG SOMEWHERE ALONG THE
APPALACHIANS...BUT THERE HAS BEEN LITTLE RUN TO RUN CONSISTENCY SO
FAR.
KANOFSKY
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 658 AM CDT WED JUL 10 2013
COVERAGE OF ELEVATED CONVECTION HAS RAPIDLY INCREASED
OVER THE LAST FEW HOURS...BUT STILL EXPECTING THIS ACTIVITY TO
SHIFT TO THE SE DURING THE MORNING. APPROXIMATE BACK EDGE OF THE
PRECIP IS NEAR A BOONEVILLE...UIN LINE...SO WHILE COU WILL BE OUT
OF THE THUNDER THREAT SHORTLY STL AREA TAFS WILL REMAIN WITH
TEMPOS FOR TSRA UNTIL LATE MORNING. PREVAILING CONDITIONS WILL BE
VFR CIGS AOA 5KFT...BUT WITH THE HIT AND MISS STRONG CORES VSBYS
WILL CERTAINLY DROP TO IFR...WITH CIGS AT LEAST DIPPING INTO THE
MVFR RANGE. WILL BE WATCHING RADAR TRENDS TO DETERMINE IF
AMENDMENTS WILL BE NECESSARY FOR THESE LOWER CONDITIONS. STILL
UNCERTAIN HOW ANY ADDITIONAL ACTIVITY WILL EVOLVE BY THIS
AFTERNOON...BUT IN SPITE OF WEAKENING CONVERGENCE ALONG
FRONT AND WITH BOUNDARY FROM THIS MORNINGS ACTIVITY SETTING UP S
OF OUR CWA...THINK THAT REDEVELOPMENT MAY STILL OCCUR NEAR THE
SYNOPTIC FRONT DUE TO RESIDUAL INSTABILITY AND WEAK UPPER LEVEL
DYNAMICS DIPPING INTO THE AREA. SO...FOLLOWING THE LEAD OF THE
LATEST HRRR DATA WILL REINTRODUCE VCTS IN STL FOR A BRIEF PERIOD
EARLY THIS AFTERNOON...BEFORE FROPA PUSHES ACTIVITY S INTO SE MO/S IL.
TRANQUIL CONDITIONS SHOULD PREVAIL THROUGHOUT THE AREA THIS
EVENING...WITH CLEAR SKIES AND NORTH WINDS AOB 10 KTS.
SPECIFICS FOR KSTL...
BASED ON ABOVE REASONING WILL BE CARRYING TEMPO TSRA THROUGH 15Z
WITH VFR CIGS AND MVFR VSBYS....BUT AS MENTIONED WILL BE WATCHING
RADAR TRENDS TO DETERMINE IF MORE INTENSE CORES WILL IMPACT THE
TERMINAL AREA. PRECIP THREAT SHOULD BRIEFLY LULL BEFORE
REINTRODUCTION OF TSRA AS FRONTAL BOUNDARY MOVES THROUGH IN THE
18-20Z TIME FRAME...BUT AFTER 20Z FRONT SHOULD BE FAR ENOUGH SOUTH
THAT THREAT WILL END. LATE AFTERNOON AND INTO THE EVENING SHOULD
GENERALLY BE CLEAR/VFR...WITH LIGHT NORTH WINDS 5-10KTS.
TRUETT
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS GLASGOW MT
913 PM MDT THU JUL 11 2013
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH SATURDAY...
DEEP MONSOONAL MOISTURE IS SEEN BEING TAPPED ON SATELLITE. RADAR
RETURNS HAVE NOT DIMINISHED ACROSS THE EASTERN TWO-THIRDS OF THE
STATE AND FEEL THAT THE MODELS ARE TOO DRY IN REGARDS TO QPF
OVERNIGHT. THEREFORE KEPT SCATTERED MENTION OF SHOWERS/TSTORMS
FOR THE SE ZONES FOR THE EVENING WITH SLIGHT CHANCE
ELSEWHERE...THAT DIMINISHED TO A SLIGHT CHANCE OVER THE EASTERN
ZONES AFTER MIDNIGHT. JAMBA
PREVIOUS DISCUSSION...
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...
EXPECT BROKEN LOW-TO-MID CLOUDS FROM THE SOUTHWEST THIS EVENING
WITH SOME VIRGA AND MAY A FEW LIGHT SHOWERS. THERE MIGHT ALSO BE
AN OCCASIONAL LIGHTNING STRIKE. HOWEVER EXPECT VFR TONIGHT AND
LIGHT AND VARIABLE WIND.
FRIDAY WILL SEE MOSTLY MID-TO-HIGH CLOUDS AND LIGHT NORTHWEST
WIND. SCT
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1253 PM CDT WED JUL 10 2013
.SYNOPSIS...
ISSUED AT 313 AM CDT WED JUL 10 2013
THE 07Z MSL ANALYSIS SHOWED TWO MAIN BOUNDARIES ACROSS THE PLAINS.
ONE WAS THE SURFACE FRONT FROM A LOW IN SOUTHEAST COLORADO ACROSS
OKLAHOMA TO SOUTHWEST MISSOURI. THE OTHER WAS A TROUGH WITH ITS
PRESENCE BETRAYED BY WIND FIELDS ACROSS SOUTHWEST NEBRASKA.
SATELLITE DERIVED PRODUCT IMAGERY...WHERE IT WAS NOT POLLUTED WITH
CLOUD...SHOWED AN AXIS OF MAXIMUM PRECIPITABLE WATER AND INSTABILITY
FROM EAST CENTRAL WYOMING ACROSS THE NEBRASKA PANHANDLE AND
SOUTHWEST NEBRASKA TO SOUTHEAST NEBRASKA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 313 AM CDT WED JUL 10 2013
ONCE AGAIN...THE LOCATIONS OF CONVECTIVE DEVELOPMENT WILL DEPEND ON
THE LOCATIONS OF THE FRONT AND OTHER BOUNDARIES FROM CONVECTION
OVERNIGHT. IT IS DIFFICULT TO FIND ANY CONSENSUS AMONG THE AVAILABLE
MODELS WITH THE SHORT RANGE FORECAST. THE RAP13 AND HRRR SEEM TO
BE ON THE SAME PAGE WITH CONVECTION DEVELOPING FAIRLY EARLY TODAY
IN WESTERN NEBRASKA. THE GEM REGIONAL AND THE GFS SEEM TO FAVOR
THIS EVENING AND LATE NIGHT FOR THE TIMING.
AS WAS THE CASE YESTERDAY...THE LOCATION OF BOUNDARIES AND THE FRONT
IS A LITTLE UP IN THE AIR. AT FIRST...CENTRAL AND SOUTHWEST NEBRASKA
APPEARS TO BE THE LOCATION TO WATCH WHERE THERE WAS CONVECTION
YESTERDAY EVENING. LOOKING AT THE RAP13 CONVECTIVE PARAMETERS...THE
SURFACE-BASED CONVECTIVE INHIBITION APPROACHES ZERO J/KG BY LATE
MORNING TO EARLY AFTERNOON IN THE SOUTHWEST. ALSO...CONVECTIVE
POTENTIAL ENERGY OF 1500-2500J/KG AND SFC-6KM BULK SHEAR INCREASING
TO 40-50KT COULD SUPPORT LARGE HAIL.
FOR LATER PERIODS...THE FRONT LIFTING ONTO THE HIGH PLAINS WOULD BE
A GOOD FOCUS FOR CONVECTION TO DEVELOP THIS EVENING OR OVERNIGHT AS
IT MOVES INTO WESTERN NEBRASKA.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 313 AM CDT WED JUL 10 2013
THE EXPANSIVE RIDGE OF HIGH PRESSURE THAT HAS BEEN ANCHORED ACROSS
THE FOUR CORNERS REGION FOR DAYS...WILL BUILD NORTH OVER OUR AREA
THURSDAY INTO FRIDAY. THIS WILL BRING WARMING TEMPERATURES
ALOFT...WHICH WILL CAP THE ATMOSPHERE...AND LITTLE IN THE WAY OF
T-STORM ACTIVITY IS EXPECTED. IT WILL BE QUITE HOT AS WELL...WITH
HIGHS IN THE 90S TO AROUND 100 DEGREES. HUMIDITY WILL REMAIN AS
WELL...ESPECIALLY EAST OF HIGHWAY 83...AND A HEAT ADVISORY MAY BE
NEEDED FRIDAY AND POSSIBLE SATURDAY.
BY LATER SATURDAY INTO SUNDAY...A SHORTWAVE WILL SKIRT ACROSS
CANADA. THIS WILL DRIVE A COLD FRONT SOUTH INTO THE REGION...WITH
RETURNING CHANCES FOR T-STORMS WITH THE ARRIVAL OF THE FRONT. THE
UPPER LEVEL HIGH WILL ALSO BE TEMPORALLY SUPPRESSED SOUTH...WITH
TEMPERATURES COOLING JUST A FEW DEGREES.
THE RIDGE IS FORECASTED TO BUILD OVERHEAD AGAIN BY TUESDAY INTO
WEDNESDAY...WITH HOT WEATHER CONTINUE AND ONLY AN ISOLATED T-STORM
AT BEST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1253 PM CDT WED JUL 10 2013
THE KLNX WSR-88D IS CURRENTLY INTERROGATING TWO AREAS OF
CONVECTIVE RAINFALL...THE FIRST ACROSS SOUTHWEST NEBRASKA...JUST
WEST OF THE KLBF TERMINAL...AND THE SECOND MORE ISOLATED...BUT
CONTINUING TO ADVANCE EAST/SOUTHEAST FROM THE BADLANDS REGION OF
SOUTH DAKOTA...ON TRACK TO PASS OVER THE KVTN TERMINAL THIS
AFTERNOON. THUS INTRODUCED -SHRA AND/OR -TSRA TO THE TAF FORECAST FOR
THIS AFTERNOON AT BOTH THE KVTN AND KLBF TERMINALS. NEAR TERM
GUIDANCE HAS STRUGGLED THUS FAR WITH THE WITH THE ONGOING
STORMS...AS AREAL COVERAGE AND TIMING OF THE CONVECTION IS ALL
OVER THE PLACE. BECAUSE OF THIS...FORECAST CONFIDENCE IS LOWER THAN
USUAL. LATER TODAY/TONIGHT...ADDITIONAL STORM DEVELOPMENT IS
POSSIBLE ACROSS THE HIGHER TERRAIN OF EASTERN COLORADO/WYOMING AND
ACROSS NORTH CENTRAL NEBRASKA OVERNIGHT. UNCERTAINTY REMAINS
HOWEVER AS TO HOW FAR EAST/SOUTH THIS ACTIVITY WILL LAST...SO FOR NOW
WILL LEAVE THE FORECAST DRY FOR THE HOURS BEYOND MID-AFTERNOON AT
KLBF AND KVTN AS POP CHANCES REMAIN LESS THAN 30 PERCENT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SPRINGER
SHORT TERM...SPRINGER
LONG TERM...TAYLOR
AVIATION...JACOBS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
642 AM CDT WED JUL 10 2013
.SYNOPSIS...
ISSUED AT 313 AM CDT WED JUL 10 2013
THE 07Z MSL ANALYSIS SHOWED TWO MAIN BOUNDARIES ACROSS THE PLAINS.
ONE WAS THE SURFACE FRONT FROM A LOW IN SOUTHEAST COLORADO ACROSS
OKLAHOMA TO SOUTHWEST MISSOURI. THE OTHER WAS A TROUGH WITH ITS
PRESENCE BETRAYED BY WIND FIELDS ACROSS SOUTHWEST NEBRASKA.
SATELLITE DERIVED PRODUCT IMAGERY...WHERE IT WAS NOT POLLUTED WITH
CLOUD...SHOWED AN AXIS OF MAXIMUM PRECIPITABLE WATER AND INSTABILITY
FROM EAST CENTRAL WYOMING ACROSS THE NEBRASKA PANHANDLE AND
SOUTHWEST NEBRASKA TO SOUTHEAST NEBRASKA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 313 AM CDT WED JUL 10 2013
ONCE AGAIN...THE LOCATIONS OF CONVECTIVE DEVELOPMENT WILL DEPEND ON
THE LOCATIONS OF THE FRONT AND OTHER BOUNDARIES FROM CONVECTION
OVERNIGHT. IT IS DIFFICULT TO FIND ANY CONSENSUS AMONG THE AVAILABLE
MODELS WITH THE SHORT RANGE FORECAST. THE RAP13 AND HRRR SEEM TO
BE ON THE SAME PAGE WITH CONVECTION DEVELOPING FAIRLY EARLY TODAY
IN WESTERN NEBRASKA. THE GEM REGIONAL AND THE GFS SEEM TO FAVOR
THIS EVENING AND LATE NIGHT FOR THE TIMING.
AS WAS THE CASE YESTERDAY...THE LOCATION OF BOUNDARIES AND THE FRONT
IS A LITTLE UP IN THE AIR. AT FIRST...CENTRAL AND SOUTHWEST NEBRASKA
APPEARS TO BE THE LOCATION TO WATCH WHERE THERE WAS CONVECTION
YESTERDAY EVENING. LOOKING AT THE RAP13 CONVECTIVE PARAMETERS...THE
SURFACE-BASED CONVECTIVE INHIBITION APPROACHES ZERO J/KG BY LATE
MORNING TO EARLY AFTERNOON IN THE SOUTHWEST. ALSO...CONVECTIVE
POTENTIAL ENERGY OF 1500-2500J/KG AND SFC-6KM BULK SHEAR INCREASING
TO 40-50KT COULD SUPPORT LARGE HAIL.
FOR LATER PERIODS...THE FRONT LIFTING ONTO THE HIGH PLAINS WOULD BE
A GOOD FOCUS FOR CONVECTION TO DEVELOP THIS EVENING OR OVERNIGHT AS
IT MOVES INTO WESTERN NEBRASKA.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 313 AM CDT WED JUL 10 2013
THE EXPANSIVE RIDGE OF HIGH PRESSURE THAT HAS BEEN ANCHORED ACROSS
THE FOUR CORNERS REGION FOR DAYS...WILL BUILD NORTH OVER OUR AREA
THURSDAY INTO FRIDAY. THIS WILL BRING WARMING TEMPERATURES
ALOFT...WHICH WILL CAP THE ATMOSPHERE...AND LITTLE IN THE WAY OF
T-STORM ACTIVITY IS EXPECTED. IT WILL BE QUITE HOT AS WELL...WITH
HIGHS IN THE 90S TO AROUND 100 DEGREES. HUMIDITY WILL REMAIN AS
WELL...ESPECIALLY EAST OF HIGHWAY 83...AND A HEAT ADVISORY MAY BE
NEEDED FRIDAY AND POSSIBLE SATURDAY.
BY LATER SATURDAY INTO SUNDAY...A SHORTWAVE WILL SKIRT ACROSS
CANADA. THIS WILL DRIVE A COLD FRONT SOUTH INTO THE REGION...WITH
RETURNING CHANCES FOR T-STORMS WITH THE ARRIVAL OF THE FRONT. THE
UPPER LEVEL HIGH WILL ALSO BE TEMPORALLY SUPPRESSED SOUTH...WITH
TEMPERATURES COOLING JUST A FEW DEGREES.
THE RIDGE IS FORECASTED TO BUILD OVERHEAD AGAIN BY TUESDAY INTO
WEDNESDAY...WITH HOT WEATHER CONTINUE AND ONLY AN ISOLATED T-STORM
AT BEST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 640 AM CDT WED JUL 10 2013
ISOLATED THUNDERSTORMS DEVELOPING IN WESTERN NEBRASKA THIS MORNING
WILL INCREASE IN COVERAGE AND SPREAD EAST TO CENTRAL AND SOUTHWEST
NEBRASKA BY MID-AFTERNOON. THE STORMS MAY AFFECT MHN...TIF...BBW...
LBF...OGA AND IML. HOWEVER...WITH LIMITED COVERAGE...THE PROBABILITY
IS NOT HIGH ENOUGH TO INCLUDE IN THE TERMINAL FORECAST FOR LBF.
EXCEPT IN AND NEAR THUNDERSTORMS...CEILING AND VISIBILITY WILL NOT
RESULT IN ANY LIMITATIONS TO FLIGHT OPERATIONS.
LIGHT AND VARIABLE WIND WILL BECOME SOUTHEAST AND INCREASE TO
10-15G17-22KT. IN THE VICINITY OF THUNDERSTORMS WIND WILL BE
VRB20-26G34-45KT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SPRINGER
SHORT TERM...SPRINGER
LONG TERM...TAYLOR
AVIATION...SPRINGER
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
328 AM CDT WED JUL 10 2013
.SYNOPSIS...
ISSUED AT 313 AM CDT WED JUL 10 2013
THE 07Z MSL ANALYSIS SHOWED TWO MAIN BOUNDARIES ACROSS THE PLAINS.
ONE WAS THE SURFACE FRONT FROM A LOW IN SOUTHEAST COLORADO ACROSS
OKLAHOMA TO SOUTHWEST MISSOURI. THE OTHER WAS A TROUGH WITH ITS
PRESENCE BETRAYED BY WIND FIELDS ACROSS SOUTHWEST NEBRASKA.
SATELLITE DERIVED PRODUCT IMAGERY...WHERE IT WAS NOT POLLUTED WITH
CLOUD...SHOWED AN AXIS OF MAXIMUM PRECIPITABLE WATER AND INSTABILITY
FROM EAST CENTRAL WYOMING ACROSS THE NEBRASKA PANHANDLE AND
SOUTHWEST NEBRASKA TO SOUTHEAST NEBRASKA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 313 AM CDT WED JUL 10 2013
ONCE AGAIN...THE LOCATIONS OF CONVECTIVE DEVELOPMENT WILL DEPEND ON
THE LOCATIONS OF THE FRONT AND OTHER BOUNDARIES FROM CONVECTION
OVERNIGHT. IT IS DIFFICULT TO FIND ANY CONSENSUS AMONG THE AVAILABLE
MODELS WITH THE SHORT RANGE FORECAST. THE RAP13 AND HRRR SEEM TO
BE ON THE SAME PAGE WITH CONVECTION DEVELOPING FAIRLY EARLY TODAY
IN WESTERN NEBRASKA. THE GEM REGIONAL AND THE GFS SEEM TO FAVOR
THIS EVENING AND LATE NIGHT FOR THE TIMING.
AS WAS THE CASE YESTERDAY...THE LOCATION OF BOUNDARIES AND THE FRONT
IS A LITTLE UP IN THE AIR. AT FIRST...CENTRAL AND SOUTHWEST NEBRASKA
APPEARS TO BE THE LOCATION TO WATCH WHERE THERE WAS CONVECTION
YESTERDAY EVENING. LOOKING AT THE RAP13 CONVECTIVE PARAMETERS...THE
SURFACE-BASED CONVECTIVE INHIBITION APPROACHES ZERO J/KG BY LATE
MORNING TO EARLY AFTERNOON IN THE SOUTHWEST. ALSO...CONVECTIVE
POTENTIAL ENERGY OF 1500-2500J/KG AND SFC-6KM BULK SHEAR INCREASING
TO 40-50KT COULD SUPPORT LARGE HAIL.
FOR LATER PERIODS...THE FRONT LIFTING ONTO THE HIGH PLAINS WOULD BE
A GOOD FOCUS FOR CONVECTION TO DEVELOP THIS EVENING OR OVERNIGHT AS
IT MOVES INTO WESTERN NEBRASKA.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 313 AM CDT WED JUL 10 2013
THE EXPANSIVE RIDGE OF HIGH PRESSURE THAT HAS BEEN ANCHORED ACROSS
THE FOUR CORNERS REGION FOR DAYS...WILL BUILD NORTH OVER OUR AREA
THURSDAY INTO FRIDAY. THIS WILL BRING WARMING TEMPERATURES
ALOFT...WHICH WILL CAP THE ATMOSPHERE...AND LITTLE IN THE WAY OF
T-STORM ACTIVITY IS EXPECTED. IT WILL BE QUITE HOT AS WELL...WITH
HIGHS IN THE 90S TO AROUND 100 DEGREES. HUMIDITY WILL REMAIN AS
WELL...ESPECIALLY EAST OF HIGHWAY 83...AND A HEAT ADVISORY MAY BE
NEEDED FRIDAY AND POSSIBLE SATURDAY.
BY LATER SATURDAY INTO SUNDAY...A SHORTWAVE WILL SKIRT ACROSS
CANADA. THIS WILL DRIVE A COLD FRONT SOUTH INTO THE REGION...WITH
RETURNING CHANCES FOR T-STORMS WITH THE ARRIVAL OF THE FRONT. THE
UPPER LEVEL HIGH WILL ALSO BE TEMPORALLY SUPPRESSED SOUTH...WITH
TEMPERATURES COOLING JUST A FEW DEGREES.
THE RIDGE IS FORECASTED TO BUILD OVERHEAD AGAIN BY TUESDAY INTO
WEDNESDAY...WITH HOT WEATHER CONTINUE AND ONLY AN ISOLATED T-STORM
AT BEST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1130 PM CDT TUE JUL 9 2013
MOSTLY CLEAR SKIES ARE EXPECTED OVERNIGHT AT BOTH THE KVTN AND
KLBF TERMINALS...WITH SOME SCATTERED HIGH CLOUDINESS POSSIBLE. SOME
SCATTERED MID LEVEL CLOUDINESS WILL DEVELOP WEDNESDAY AFTERNOON AS
A DISTURBANCE APPROACHES WESTERN AND NORTH CENTRAL NEBRASKA.
ISOLATED THUNDERSTORMS WILL BE POSSIBLE...PARTICULARLY OVER
SOUTHWESTERN AND WESTERN NEBRASKA WEDNESDAY AFTERNOON AND EVENING.
WITH LIMITED COVERAGE EXPECTED...WILL FORGO MENTION OF
THUNDERSTORMS IN THE 06Z TAFS. WINDS WILL BE FROM THE EAST
SOUTHEAST OR SOUTHEAST ON WEDNESDAY AT 10 TO 20 KTS...DIMINISHING
WEDS EVENING TO UNDER 10 KTS.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SPRINGER
SHORT TERM...SPRINGER
LONG TERM...TAYLOR
AVIATION...BUTTLER
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1155 PM CDT TUE JUL 9 2013
.UPDATE...
UPDATED TO KEEP SMALL POPS IN THE FAR SOUTHEAST PART OF
NEBRASKA...BUT LET GO OF THE SEVERE THUNDERSTORM WATCH.
&&
.DISCUSSION...
AN OUTLFLOW BOUNDARY IS PUSHING TOWARD THE NEBRASKA/KANSAS
BORDER...SO LEFT SOME ISOLATED TSRA CHANCES INTO THE FAR SOUTHEAST
NEBRASKA ZONES AND COULD SEE SOME WINDS GUSTS TO 30 OR 35 MPH.
OTHERWISE COOLER...RELATIVELY DRIER CONDITIONS WILL BUILD IN
TONIGHT
&&
.AVIATION...
06Z TAFS FOR KOFK...KLNK AND KOMA.
VFR CONDITIONS EXPECTED THROUGH THE PERIOD AS HIGH PRESSURE BUILDS
INTO THE REGION.
&&
.PREV DISCUSSION... /ISSUED 654 PM CDT TUE JUL 9 2013/
UPDATE...
UPDATE TO INCLUDE SEVERE THUNDERSTORM WATCH FOR PARTS OF SOUTHEAST
NEBRASKA THROUGH 1AM AND ALLOW THE HEAT ADVISORY TO EXPIRE.
DISCUSSION...
SOME STORMS HAVE DEVELOPED IN THE UPSLOPE REGION IN WESTERN AND
CENTRAL NEBRASKA AND HAVE CONTINUED THIS EVENING. THERE IS A COLD
FRONT WITH POOLING OF INSTABILITY AND DECENT DEEP LAYER SHEAR
AHEAD OF THE FRONT...VERY WARM TEMPERATURE ARE HINDERING STORM
DEVELOPMENT FARTHER THUS FAR. SHOULD STORMS DEVELOP...THEY COULD
BECOME SEVERE.
AVIATION...
00Z TAFS FOR KOFK...KLNK AND KOMA.
VFR CONDITIONS THROUGH THE PERIOD. WILL CONTINUE TO MONITOR STORM
DEVELOPMENT FROM CENTRAL NEBRASKA. FOR NOW AM COUNTING ON STORMS
TO BE SOUTH OF THE LNK TAF SITE AND HAVE NOT INCLUDED IN THE TAF.
A COLD FRONT IS PUSHING THROUGH AND NORTH SURFACE WINDS MAY BUMP
UP TO 10 TO 15KT BEHIND IT...BUT SHOULD SETTLE DOWN AFTER 02Z-03Z.
PREV DISCUSSION... /ISSUED 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
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
ZAPOTOCNY
AREA FORECAST DISCUSSION
NWS BUFFALO NY
454 PM EDT WED JUL 10 2013
.SYNOPSIS...
SHOWERS AND THUNDERSTORMS WILL SWEEP ACROSS THE REGION THIS
EVENING AS A COLD FRONT MOVES ACROSS THE REGION. SOME OF THESE
STORMS COULD BE SEVERE. FOLLOWING THE PASSAGE OF THE COLD FRONT
EXPECT COOLER AND LESS HUMID CONDITIONS THAN WHAT WE HAVE SEEN
THIS PAST WEEK WITH AN ISOLATED SHOWER POSSIBLE THURSDAY
AFTERNOON. HIGH PRESSURE WILL BUILD OVER OUR AREA BEHIND THE FRONT
THURSDAY NIGHT THROUGH THE BEGINNING OF NEXT WEEK WITH DRY
WEATHER.
&&
.NEAR TERM /THROUGH THURSDAY/...
SEVERE THUNDERSTORM WATCH IN EFFECT UNTIL 10PM FOR WESTERN NEW YORK.
A VIGOROUS NEGATIVELY TILTING TROUGH WITH EMBEDDED 60 KT MID LEVEL
JET IS LOCATED ALOFT WITH AXIS OVER LAKE HURON THIS AFTERNOON. LOW
PRESSURE AT THE SURFACE IS CENTERED OVER WEST CENTRAL QUEBEC WITH A
COLD FRONT EXTENDING SOUTH OF THE LOW TO JUST NORTH OF TORONTO THEN
SOUTHWEST ACROSS LOWER ONTARIO PROVINCE TO NEAR DETROIT MICHIGAN.
TWO FOCUS AREAS FOR STORMS AHEAD OF AND ALONG THE COLD FRONT ARE
SEEN ON RADAR. ONE LARGE CLUSTER WHICH IS MERGING INTO A LINE IS
FOUND FROM CHAUTAUQUA COUNTY SOUTHWEST ACROSS OHIO TO CENTRAL
KENTUCKY. A SECOND AREA OF STORMS WHICH IS ORIENTED ALONG THE COLD
FRONT IS ADVANCING ACROSS SOUTHERN ONTARIO PROVINCE TO THE NORTH OF
LAKE ERIE.
WESTERN AND NORTH CENTRAL NEW YORK LIES WITHIN THE WARM SECTOR OF
THE SURFACE LOW WITH DEWPOINTS IN THE LOW 70 AND GUSTY SOUTHWEST
WINDS. VISIBLE SATELLITE IMAGERY SHOWS AN EXTENSIVE CUMULUS FILED
HAS DEVELOPED OVER THE GENESEE VALLEY AND FINGER LAKES WITH SOME
OVERCAST ASSOCIATED WITH CONVECTIVE DEBRIS NOW WORKING OVER FAR
WESTERN NEW YORK. BREAKS IN THE OVERCAST ARE ALSO WORKING IN ALONG
THE I-81 CORRIDOR WITH THICK CLOUD COVER TO THE EAST. THE BREAKS IN
THE CLOUD COVER ARE ALLOWING FOR CONDITIONS TO BECOME MORE UNSTABLE
SPC MESOANALYSIS SHOWS UP TO 2500 J/KG CAPE ACROSS INTERIOR SECTIONS
OF WESTERN NEW YORK BUT THE LAKES ARE KEEPING MUCH OF THE LAKESHORE
AREAS CAPPED. AS THE COLD FRONT APPROACHES OUR REGION LATER THIS
SHOWERS AND THUNDERSTORMS WILL ALSO ADVANCE EASTWARD.
MODEL GUIDANCE AND CURRENT OBSERVATIONS SHOW THE BEST PROBABILITY
FOR STORMS WILL BE ACROSS THE SOUTHERN TIER COUNTIES AND INLAND
SECTIONS OF WESTERN NY AWAY FROM THE LAKES THIS AFTERNOON AND EVENING
WITH CHANCES INCREASING FOR THE EASTERN LAKE ONTARIO REGION AFTER
00Z. RAP MODEL BUFKIT SOUNDING SHOW THAT STORM TOPS MAY EXTEND TO
35-40 KFT WHICH MATCHES UP WELL WITH KBUF ENHANCED ECHO TOPS
PRODUCT. A FEW OF THE STRONGER CELLS ARE EXHIBITING TOPS TO 50+KFT
OVER OHIO AND PA. THE MAIN THREATS FROM THESE STORMS WITH SUFFICIENT
CAPE AVAILABLE WITHIN THE HAIL GROWTH ZONE IS FOR LARGE HAIL AND
UNIDIRECTIONAL VERTICAL WIND SHEAR UP TO 50 KNOTS WOULD ALSO ALLOW
FOR DAMAGING WINDS WITHIN ANY LINE SEGMENTS AND LARGER CELLS.
LOCALIZED HEAVY RAIN IS ALSO A THREAT WITH THESE STORMS AS PWATS
WILL RUN UP TO 2 INCHES AHEAD OF THE FRONT.
AFTER SUNSET...THE FRONT SHOULD BEGIN TO MAKE A GOOD PROGRESS
EASTWARD ACROSS WESTERN NEW YORK...WITH GRADUAL CLEARING BEHIND THE COLD
FRONT. THE MOST NOTABLE CLEARING WILL BE ALONG THE LAKE SHORE
COUNTIES TOWARD MORNING. A WEST TO NORTHWEST UPSLOPE FLOW MAY KEEP
SOME CLOUDS OVER THE INLAND LOCATIONS FOR MUCH OF THE NIGHT. DESPITE
THE FRONT SWEEPING THROUGH TEMPERATURES OVERNIGHT WILL REMAIN MILD
AS THE DRIER AIR WILL TAKE SOME TIME TO MIX ACROSS OUR REGION. LOWS
WILL RUN IN THE LOWER 60S.
ON THURSDAY THE AXIS OF THE UPPER LEVEL TROUGH WILL CROSS OVER
WESTERN AND CENTRAL NEW YORK WITH THE COLD FRONT FOUND ACROSS
EASTERN NEW YORK SOUTH TO THE MID-ATLANTIC REGION. WHILE THE
ATMOSPHERE WILL BE IN A MUCH DRIER STATE BEHIND THE FRONT THERE IS A
LOW CHANCE OF SOME ISOLATED SHOWERS DEVELOPING DURING THE AFTERNOON
ASSOCIATED WITH THE SYNOPTIC LIFT OF THE TROUGH AS IT SWEEPS EASTWARD.
THIS MOISTURE WOULD BE FOUND MAINLY IN THE 700-900MB LAYER WITH NAM
PROFILES SHOWING A CAP ABOVE THIS LEVEL. THIS CAP WOULD KEEP A LID
ON ANY ACTIVITY THAT MAY DEVELOP PREVENTING THUNDERSTORMS.
TEMPERATURES WILL BE VERY COMFORTABLE FOR THE FIRST TIME IN MORE
THAN A WEEK WITH HIGHS MAXING OUT IN THE 70S.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
AN UPPER LEVEL TROF WILL SLOWLY MOVE ACROSS THE REGION ON THURSDAY
NIGHT. THERE MAY BE A FEW LINGERING SHOWERS DUE TO LEFT OVER DAYTIME
INSTABILITY ON THURSDAY EVENING. LATER IN THE NIGHT...SHOWERS MAY
LINGER A BIT LONGER SOUTHEAST OF LAKE ONTARIO...WHERE THE EXITING
TROF AND THE NOT-SO COLD LAKE WATERS MAY ACTUALLY ENHANCE CHANCES A
BIT. NAM/GFS BUFKIT FORECAST SOUNDING SHOWS A MODEST CAP AT 10K
FEET...WHICH SHOULD KEEP ANY SHOWERS ON THE LIGHT SIDE. THIS COOLER
AIRMASS WILL ALLOW TEMPS TO DROP INTO THE UPPER 50S TO LOWER 60S IN
MOST LOCATIONS...WITH MID 50S IN THE COOLER SPOTS OF THE SOUTHERN
TIER AND EAST OF LAKE ONTARIO.
BY FRIDAY...SURFACE HIGH PRESSURE WILL BE ACROSS EASTERN MICHIGAN.
MODEL GUIDANCE DIFFERS ON THE HANDLING OF A CUT-OFF UPPER LOW...WITH
GUIDANCE DIFFERING ON WHERE THIS SUBTLE FEATURE WILL BE. FOR THE
MOST PART...A BROAD MODEL CONSENSUS PUTS THE UPPER LEVEL TROF AXIS
OR CUT OFF LOW ACROSS EASTERN NEW YORK...WITH THE SREF PROBABLY THE
BEST REPRESENTATION OF THIS. HAVE HIGH CONFIDENCE IN A DRY FORECAST
ON FRIDAY ROCHESTER WESTWARD...WITH ONLY A MARGINAL CHANCE
FOR ANY SHOWERS IN EASTERN PORTIONS OF THE CWA BASED ON WHERE THE
UPPER TROF IS. EXPECT A FAIR AMOUNT OF SUNSHINE ON THE BACK OF THE
EXITING TROF...WITH A NORTHERLY FLOW OFF THE LAKES LIKELY TO KEEP
TEMPERATURES COOLER NEAR THE LAKES SOUTH SHORES. INLAND OF
THIS...EXPECT HIGHS IN THE UPPER 70S.
THE TROF AXIS SHOULD SLIDE EVER SO SLOWLY TO THE EAST INTO NEW
ENGLAND ON FRIDAY NIGHT...WITH SOME MODELS STILL KEEPING THE LOW
ACROSS EASTERN NEW YORK. EITHER OF THESE SCENARIOS WOULD KEEP OUR
REGION DRY OVERNIGHT. FRIDAY NIGHT WILL BE THE COOLEST NIGHT OF THE
STRETCH AS HIGH PRESSURE REMAINS CENTERED JUST TO OUR
WEST...ALLOWING FOR LIGHT WINDS AND MAINLY CLEAR SKIES FOR GOOD
RADIATIONAL COOLING. EXPECT LOWS IN THE 50S...COOLEST ACROSS
INTERIOR PORTIONS OF THE SOUTHERN TIER AND THE NORTH COUNTRY.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
THE WEATHER FOR THIS UPCOMING WEEKEND STILL LOOKS QUITE
NICE...WITH FAIR WEATHER AND SEASONABLY WARM MID-SUMMER
TEMPERATURES. THERE STILL WILL BE A SUBTLE CUT-OFF LOW TO CONTEND
WITH...BUT THE MAJORITY OF LONG-RANGE GUIDANCE KEEPS THIS FEATURE
ACROSS NEW ENGLAND FOR THE WEEKEND...WHICH WOULD KEEP US ON THE DRY
BACKSIDE OF THIS LOW. EVEN IF MODEL GUIDANCE IS WRONG...A POSITION
FURTHER TO THE WEST WOULD ONLY BRING MARGINAL CHANCES FOR DIURNALLY
DRIVEN SHOWERS...AND DAYTIME HIGHS A FEW DEGREES COOLER THAN THE
GOING FORECAST. SUNDAY SHOULD BE THE WARMER OF THE TWO DAYS...WITH
HIGHS IN THE MID TO UPPER 80S...A TAD COOLER ALONG THE IMMEDIATE
LAKESHORE.
FOR THE FIRST HALF OF NEXT WEEK...LARGE SCALE RIDGING IS FORECAST TO
BUILD ACROSS NEARLY THE ENTIRE CONUS...PUSHING THE JET STREAM UP
INTO CANADA. THE STALLED UPPER LOW WILL CONTINUE TO BE IN OUR
GENERAL VICINITY...UNTIL IT FINALLY SPINS ITSELF OUT BY MID-WEEK.
THIS LOW MAY BE ENOUGH TO GENERATE A FEW SHOWERS...BUT THESE SHOULD
BE SO SPARSE THAT WE WILL ONLY CARRY SLIGHT CHANCE POPS AWAY FROM
THE LAKES. MEAN 850 MB TEMPERATURES SHOULD RUN ABOUT +16C...WITH THE
GFS/GGEM AVERAGING A TAD WARMER THAN THE EUROPEAN MODEL GUIDANCE. USING A
BLEND...EXPECT DAYTIME HIGHS TO CONTINUE TO BE ON THE WARM SIDE.
INTERIOR LOCATIONS SHOULD TOP OUT IN THE UPPER 80S TO AROUND
90...WITH LOWER TO MID 80S ALONG THE IMMEDIATE LAKE SHORES. HUMIDITY
WILL BEGIN TO INCREASE AS WELL...BUT NOT AS HIGH AS WE HAVE SEEN THE
PAST 10 DAYS.
&&
.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
STRONG TO SEVERE THUNDERSTORMS WILL WORK ACROSS WESTERN NEW YORK
AHEAD OF A COLD FRONT THIS EVENING. THE STRONGEST CELLS MAY
CONTAIN HAIL TO 1.5 INCHES AND WIND GUSTS TO 60 KNOTS. EXPECT
SHRA/TSRA TO ALSO IMPACT KART BUT NOT TIL AFTER 00Z AND LOWER CHANCE
FOR SEVERE CHARACTERISTICS. ONCE THE FRONT MOVES THROUGH BETWEEN
03-06Z...EXPECT IMPROVING WEATHER ACROSS ALL AREAS WITH RESIDUAL
UPSLOPE CLOUDS INLAND...BUT WITH VFR CONDITIONS.
OUTLOOK...
THURSDAY...MAINLY VFR. A CHANCE OF SHOWERS.
FRIDAY THROUGH SUNDAY...VFR.
&&
.MARINE...
BREEZY SOUTHWEST WINDS ARE OBSERVED ON THE LAKES THIS EVENING AHEAD
OF A COLD FRONT. SHOWERS AND THUNDERSTORMS WILL SWEEP ACROSS THE
REGION THROUGH THE EVENING WITH POSSIBLE LARGE HAIL AND STRONG WIND
GUSTS. SMALL CRAFT ADVISORIES ARE IN EFFECT AS OUTLINED BELOW DUE
TO HIGHER WINDS AND WAVES OBSERVED AHEAD OF THE FRONT. FOLLOWING THE
FRONT...EXPECT HIGH PRESSURE BUILDING IN THURSDAY...LASTING WELL
INTO THE UPCOMING WEEKEND WITH LIGHT WINDS AND LITTLE WAVE ACTION.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EDT THURSDAY FOR LEZ020-040-
041.
SMALL CRAFT ADVISORY UNTIL 7 AM EDT THURSDAY FOR
LOZ043>045.
&&
$$
SYNOPSIS.../SMITH
NEAR TERM...SMITH
SHORT TERM...APFFEL
LONG TERM...APFFEL
AVIATION...SMITH
MARINE...SMITH
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
354 PM EDT WED JUL 10 2013
.SYNOPSIS...
WATCH FOR SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS
DEVELOPING ACROSS MUCH OF THE NORTH COUNTRY THIS AFTERNOON AND
EVENING. ANY STORMS WILL HAVE THE POTENTIAL TO PRODUCE GUSTY
WINDS AND VERY HEAVY RAINFALL THAT COULD LEAD TO FLASH FLOODING.
THUS A FLASH FLOOD WATCH REMAINS IN EFFECT THIS AFTERNOON THROUGH
MIDNIGHT. THE THREAT FOR PRECIPITATION WILL BE LIMITED TO EASTERN
VERMONT ON THURSDAY AND THEN DRY WEATHER WITH SEASONAL
TEMPERATURES IS EXPECTED FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 1009 AM EDT WEDNESDAY...UPDATE TO POPS THROUGH THE DAY BASED
OFF CURRENT RADAR ACTIVITY AND BLEND OF AVAILABLE CAM MODEL
OUTPUT. STILL LOOKING MORE OR LESS AT 40/70% POPS ACROSS THE AREA
TODAY...BUT DETAILED CURRENT BAND PROGRESSING EAST ACROSS CENTRAL
NY MOVING INTO THE AREA A TAD BETTER AND AS RESOLVED QUITE WELL BY
LATEST HRRR DATA. REST OF FORECAST REMAINS MORE OR LESS IN GOOD
SHAPE. HAVE A GREAT DAY. PRIOR DISCUSSION FOLLOWS...
GOING FORECAST IN GOOD SHAPE AND NO CHANGES NEEDED AT THIS TIME.
THREAT FOR FLASH FLOODING AND STRONG GUSTY WINDS WILL REMAIN
ACROSS MUCH OF THE AREA THIS AFTERNOON AND EVENING. COMPOSITE
ANALYSIS SHOWS STRONGEST DYNAMIC SUPPORT AND DEEP LAYER SHEAR WILL
REMAIN ACROSS EASTERN CANADA THIS AFTERNOON AND EVENING AS LARGE
UPPER TROUGH MOVES INTO THE AREA. LATER THIS AFTERNOON
HOWEVER...THE SOUTHERN END OF THE STRONGER FLOW ALOFT...25 KNOTS
AT 850 MB AND 30 KNOTS AT 500 MB WILL MOVE ACROSS THE SOUTHERN
HALF OF VERMONT THIS AFTERNOON. THIS COMBINED WITH CONVECTIVE
AVAILABLE POTENTIAL ENERGY APPROACHING 1000 J/KG SUGGEST SOME
ORGANIZATION TO THE STORMS WILL EXIST. THUS LOOKING AT
PULSE/MULTICELL STORMS LATER THIS AFTERNOON AND EVENING WITH THE
AREA FROM THE NORTHERN ADIRONDACKS EASTWARD TO THE CONNECTICUT
RIVER VALLEY AS THE MAIN AREA OF CONCERN. AXIS OF HIGH
PRECIPITABLE WATER AIR...VALUES AROUND 2 INCHES...WILL NOSE RIGHT
UP INTO THE AREA. SO WITH STORM MOTIONS UNDER 15 KNOTS...THE
THREAT FOR HEAVY DOWNPOURS AND FLASH FLOODING WILL EXIST
ESPECIALLY SINCE THE AREA COVERAGE OF STORMS WILL BE GREATER THAN
THE PAST COUPLE OF DAYS. THUS GOING IDEA OF A FLASH FLOOD WATCH
FOR MOST OF THE AREA STILL LOOKS GOOD. IN ADDITION...FEEL WITH
SOME ORGANIZATION TO THE STORMS...THREAT FOR STRONG GUSTY WINDS
WILL EXIST. HAVE INCLUDED THE ENHANCED WORDING IN THE FORECAST FOR
THESE TWO THREATS. WE MAY SEE CLOUDS AND SPOTTY SHOWERS MOVE
ACROSS THE AREA THIS MORNING...BUT MAIN THREAT FOR STORMS WILL BE
AFTER 200 PM.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH FRIDAY NIGHT/...
AS OF 437 AM EDT WEDNESDAY...ACTIVE WEATHER WITH STORMS
POTENTIALLY PRODUCING FLASH FLOODING WILL EXIST THROUGH MIDNIGHT
TONIGHT...THEN INTENSITY OF STORMS WILL WEAKEN OVERNIGHT AND MOVE
EAST OF THE AREA. COLD FRONT WILL BECOME PARALLEL TO THE UPPER
FLOW ON THURSDAY AND THUS THE FRONT WILL STILL HANG AROUND
EASTERN VERMONT FOR A CONTINUED CHANCE OF SHOWERS OR STORMS. HIGH
PRESSURE BUILDS IN LATE THURSDAY NIGHT AND FRIDAY FOR DRIER
WEATHER AND TEMPERATURES TRENDING SLIGHTLY BELOW NORMAL BY
FRIDAY.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 353 PM EDT WEDNESDAY...HIGH PRESSURE OVER THE GREAT LAKES
WILL PERSIST THROUGH THE WEEKEND WITH AN INVERTED TROUGH
DEVELOPING OFF THE NORTHEAST COAST. ECMWF AND GFS DEVELOP UPPER
LEVEL TROUGH ASSOCIATED WITH INVERTED TROUGH INTO CLOSED
LOW...PSBLY CREATING SLGT TO LOW CHC FOR PRECIP. AT THE
SFC...HIGH PRESSURE PERSISTS WHICH WILL AID IN KEEPING THE AREA
DRY. ECMWF THEN BUILDS RIDGE OF HIGH PRESSURE OVER NORTHEAST
PUSHING THE CLOSED LOW WESTWARD. STILL LOTS OF UNCERTAINTY THAT
FAR OUT. HAVE LEANED TOWARD DRIER ECMWF SOLUTION THROUGH EARLY
NEXT WEEK. WARM AIR WILL LEAD TO MAX TEMPS IN THE U70S-M80S AND
MIN TEMPS GENERALLY IN THE 60S.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
THROUGH 18Z THURSDAY...ACTIVE AVIATION FORECAST FOR THIS TAF
ISSUANCE. CURRENT FLIGHT CATEGORIES RANGE FROM VFR TO MVFR. PRE-
FRONTAL LINE OF SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS
EXTENDING DOWN THE CHAMPLAIN TO THE HUDSON VALLEYS WILL CONTINUE
TO PUSH EASTWARD OVER THE NEXT HOUR OR SO PRODUCING TEMPO MVFR/IFR
VISIBILITIES. THINK THE BEST CHANCE AT SEEING ANY THUNDER OUT OF
THIS INITIAL ACTIVITY IS AT RUT WHERE BETTER INSTABILITY EXISTS.
RE- DEVELOPMENT IS EXPECTED ONCE THE INITIAL SHOWERS CLEAR OUT
TIED TO THE COLD FRONT ITSELF...SOME OF WHICH COULD BE STRONG WITH
GUSTY WINDS AND POTENTIAL LLWS/TURBULENCE. HAVE TREATED WITH VCSH
AND CB FOR ALL TAFS EXCEPT MPV TO COVER THIS POTENTIAL MAINLY
AFTER 21Z. FRONT SWEEPS EAST LATE TONIGHT/OVERNIGHT WITH SHARP
WIND SHIFT TO NORTHWEST WITH DECREASE IN SHOWERS/STORMS. THE
EXCEPTION IS AT MPV AND RUT WHERE THE FRONT MAY SLOW. THINK THE
BEST CHANCE AT FOG OVERNIGHT WOULD BE AT SLK AND MSS. SHOWERS
LINGER INTO THE MORNING HOURS ESPECIALLY AT RUT AND MPV BUT
IMPROVING CONDITIONS FOR THE REST OF THE TAFS. WINDS THURSDAY WILL
TEND LIGHT WESTERLY.
OUTLOOK 18Z THURSDAY THROUGH SUNDAY...
18Z THURSDAY THRU 12Z FRIDAY...FRONT SLOWLY SHIFTS SOUTH WITH
SHOWERS ENDING AT MPV AND RUT. MAINLY VFR EXCEPT IFR/LIFR IN
MIST/FOG OVERNIGHT.
12Z FRIDAY THRU SUNDAY...MAINLY VFR EXCEPT MVFR IN PERIODS OF
SHOWERS MAINLY ACROSS RUT WITH SLOW-MOVING FRONTAL BOUNDARY.
OVERNIGHT FOG/MIST POTENTIAL 06-12Z TIMEFRAME ESPECIALLY AT SLK
AND MPV.
&&
.HYDROLOGY...
AS OF 437 AM EDT WEDNESDAY...ONCE AGAIN WE SAW ISOLATED STORMS
PRODUCE FLASH FLOODING ON TUESDAY. CONDITIONS FOR MORE FLASH
FLOODING WILL EXIST THIS AFTERNOON AND EVENING AND THE POTENTIAL
FOR FLASH FLOODING MAY ACTUALLY BE GREATER SIMPLY FOR THE FACT
THAT THERE WILL BE MORE STORMS AROUND THAN THE PAST COUPLE OF
DAYS. EXPECT SCATTERED TO NUMEROUS THUNDERSTORMS DEVELOPING OVER
THE AREA THIS AFTERNOON...ESPECIALLY FROM THE NORTHERN
ADIRONDACKS EASTWARD TO THE CONNECTICUT RIVER VALLEY. THE DEEP
LAYER OF MOISTURE IN THE ATMOSPHERE OVER THE REGION COMBINED WITH
SLOW MOVING STORMS SUGGESTS FLASH FLOODING IS POSSIBLE. THUS WILL
KEEP THE FLASH FLOOD WATCH IN PLACE. POTENTIAL IMPACTS INCLUDE
WASHED OUT AND FLOODED ROADS...FIELD FLOODING...RAPID RISES ON
SMALLER RIVERS AND STREAMS.
&&
.MARINE...
AS OF 436 AM EDT WEDNESDAY...ACTIVE WEATHER IS EXPECTED ACROSS
LAKE CHAMPLAIN TODAY THROUGH THIS EVENING. FIRST EXPECT STRONGER
WINDS OVER THE LAKE WITH SOUTH WINDS INCREASING INTO THE 20 TO 30
KNOT RANGE BY AFTERNOON AND NOT DECREASING UNTIL AFTER MIDNIGHT
TONIGHT. THESE WINDS ARE STRONGER THAN WHAT HAS BEEN FELT OVER
THE LAKE THE PAST FEW DAYS. THUS A LAKE WIND ADVISORY IS IN
EFFECT. IN ADDITION...EXPECT THUNDERSTORMS TO DEVELOP OVER
NORTHERN NEW YORK THIS AFTERNOON AND MOVE EAST ACROSS LAKE
CHAMPLAIN. BE AWARE THAT ANY STORMS WILL HAVE THE POTENTIAL TO
PRODUCE STRONG GUSTY WINDS AND AS WE HAVE SEEN THE PAST MONTH OR
SO...VERY HEAVY DOWNPOURS.
&&
.EQUIPMENT...
AS OF 436 AM EDT WEDNESDAY...THE KTYX RADAR IS DOWN UNTIL FURTHER
NOTICE. TECHS HAVE ORDERED PARTS...THOUGH RETURN TO SERVICE IS
UNKNOWN AT THIS TIME.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR VTZ001>012-
016>019.
NY...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR NYZ028>031-
034-035.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...EVENSON/JMG
SHORT TERM...EVENSON
LONG TERM...KGM/NEILES
AVIATION...NEILES/LOCONTO
HYDROLOGY...
MARINE...
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
126 PM EDT WED JUL 10 2013
.SYNOPSIS...
WATCH FOR SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS
DEVELOPING ACROSS MUCH OF THE NORTH COUNTRY THIS AFTERNOON AND
EVENING. ANY STORMS WILL HAVE THE POTENTIAL TO PRODUCE GUSTY
WINDS AND VERY HEAVY RAINFALL THAT COULD LEAD TO FLASH FLOODING.
THUS A FLASH FLOOD WATCH REMAINS IN EFFECT THIS AFTERNOON THROUGH
MIDNIGHT. THE THREAT FOR PRECIPITATION WILL BE LIMITED TO EASTERN
VERMONT ON THURSDAY AND THEN DRY WEATHER WITH SEASONAL
TEMPERATURES IS EXPECTED FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 1009 AM EDT WEDNESDAY...UPDATE TO POPS THROUGH THE DAY BASED
OFF CURRENT RADAR ACTIVITY AND BLEND OF AVAILABLE CAM MODEL
OUTPUT. STILL LOOKING MORE OR LESS AT 40/70% POPS ACROSS THE AREA
TODAY...BUT DETAILED CURRENT BAND PROGRESSING EAST ACROSS CENTRAL
NY MOVING INTO THE AREA A TAD BETTER AND AS RESOLVED QUITE WELL BY
LATEST HRRR DATA. REST OF FORECAST REMAINS MORE OR LESS IN GOOD
SHAPE. HAVE A GREAT DAY. PRIOR DISCUSSION FOLLOWS...
GOING FORECAST IN GOOD SHAPE AND NO CHANGES NEEDED AT THIS TIME.
THREAT FOR FLASH FLOODING AND STRONG GUSTY WINDS WILL REMAIN
ACROSS MUCH OF THE AREA THIS AFTERNOON AND EVENING. COMPOSITE
ANALYSIS SHOWS STRONGEST DYNAMIC SUPPORT AND DEEP LAYER SHEAR WILL
REMAIN ACROSS EASTERN CANADA THIS AFTERNOON AND EVENING AS LARGE
UPPER TROUGH MOVES INTO THE AREA. LATER THIS AFTERNOON
HOWEVER...THE SOUTHERN END OF THE STRONGER FLOW ALOFT...25 KNOTS
AT 850 MB AND 30 KNOTS AT 500 MB WILL MOVE ACROSS THE SOUTHERN
HALF OF VERMONT THIS AFTERNOON. THIS COMBINED WITH CONVECTIVE
AVAILABLE POTENTIAL ENERGY APPROACHING 1000 J/KG SUGGEST SOME
ORGANIZATION TO THE STORMS WILL EXIST. THUS LOOKING AT
PULSE/MULTICELL STORMS LATER THIS AFTERNOON AND EVENING WITH THE
AREA FROM THE NORTHERN ADIRONDACKS EASTWARD TO THE CONNECTICUT
RIVER VALLEY AS THE MAIN AREA OF CONCERN. AXIS OF HIGH
PRECIPITABLE WATER AIR...VALUES AROUND 2 INCHES...WILL NOSE RIGHT
UP INTO THE AREA. SO WITH STORM MOTIONS UNDER 15 KNOTS...THE
THREAT FOR HEAVY DOWNPOURS AND FLASH FLOODING WILL EXIST
ESPECIALLY SINCE THE AREA COVERAGE OF STORMS WILL BE GREATER THAN
THE PAST COUPLE OF DAYS. THUS GOING IDEA OF A FLASH FLOOD WATCH
FOR MOST OF THE AREA STILL LOOKS GOOD. IN ADDITION...FEEL WITH
SOME ORGANIZATION TO THE STORMS...THREAT FOR STRONG GUSTY WINDS
WILL EXIST. HAVE INCLUDED THE ENHANCED WORDING IN THE FORECAST FOR
THESE TWO THREATS. WE MAY SEE CLOUDS AND SPOTTY SHOWERS MOVE
ACROSS THE AREA THIS MORNING...BUT MAIN THREAT FOR STORMS WILL BE
AFTER 200 PM.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH FRIDAY/...
AS OF 437 AM EDT WEDNESDAY...ACTIVE WEATHER WITH STORMS
POTENTIALLY PRODUCING FLASH FLOODING WILL EXIST THROUGH MIDNIGHT
TONIGHT...THEN INTENSITY OF STORMS WILL WEAKEN OVERNIGHT AND MOVE
EAST OF THE AREA. COLD FRONT WILL BECOME PARALLEL TO THE UPPER
FLOW ON THURSDAY AND THUS THE FRONT WILL STILL HANG AROUND
EASTERN VERMONT FOR A CONTINUED CHANCE OF SHOWERS OR STORMS. HIGH
PRESSURE BUILDS IN LATE THURSDAY NIGHT AND FRIDAY FOR DRIER
WEATHER AND TEMPERATURES TRENDING SLIGHTLY BELOW NORMAL BY
FRIDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 437 AM EDT WEDNESDAY...THE PATTERN CHANGE TO A WESTERLY
FLOW OF DRIER WEATHER WILL PERSIST FRIDAY NIGHT THRU TUESDAY WITH
A WARMING TREND. HIGH PRESSURE WILL PERSIST THROUGH THE WEEKEND
INTO EARLY NEXT WEEK WITH UPPER LEVEL RIDGING AND A NW TO W FLOW
ALOFT. DO NOT SEE ANY SIGNIFICANT CHANCE FOR PRECIPITATION IN THE
EXTENDED. STILL LOTS OF UNCERTAINTY THAT FAR OUT...BUT GFS AND
NAM BOTH HINT AT SOME SHOWERS AROUND FRIDAY NIGHT AND SATURDAY.
HAVE LEANED TOWARDS DRIER ECMWF AT THIS POINT. TEMPERATURES WILL
START OUT SLIGHTLY BELOW NORMAL...BUT TREND BACK OVER NORMAL
TOWARDS THE END OF THE PERIOD.
&&
.AVIATION /17Z WEDNESDAY THROUGH MONDAY/...
THROUGH 18Z THURSDAY...ACTIVE AVIATION FORECAST FOR THIS TAF
ISSUANCE. CURRENT FLIGHT CATEGORIES RANGE FROM VFR TO MVFR. PRE-
FRONTAL LINE OF SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS
EXTENDING DOWN THE CHAMPLAIN TO THE HUDSON VALLEYS WILL CONTINUE
TO PUSH EASTWARD OVER THE NEXT HOUR OR SO PRODUCING TEMPO MVFR/IFR
VISIBILITIES. THINK THE BEST CHANCE AT SEEING ANY THUNDER OUT OF
THIS INITIAL ACTIVITY IS AT RUT WHERE BETTER INSTABILITY EXISTS.
RE- DEVELOPMENT IS EXPECTED ONCE THE INITIAL SHOWERS CLEAR OUT
TIED TO THE COLD FRONT ITSELF...SOME OF WHICH COULD BE STRONG WITH
GUSTY WINDS AND POTENTIAL LLWS/TURBULENCE. HAVE TREATED WITH VCSH
AND CB FOR ALL TAFS EXCEPT MPV TO COVER THIS POTENTIAL MAINLY
AFTER 21Z. FRONT SWEEPS EAST LATE TONIGHT/OVERNIGHT WITH SHARP
WIND SHIFT TO NORTHWEST WITH DECREASE IN SHOWERS/STORMS. THE
EXCEPTION IS AT MPV AND RUT WHERE THE FRONT MAY SLOW. THINK THE
BEST CHANCE AT FOG OVERNIGHT WOULD BE AT SLK AND MSS. SHOWERS
LINGER INTO THE MORNING HOURS ESPECIALLY AT RUT AND MPV BUT
IMPROVING CONDITIONS FOR THE REST OF THE TAFS. WINDS THURSDAY WILL
TEND LIGHT WESTERLY.
OUTLOOK 18Z THURSDAY THROUGH SUNDAY...
18Z THURSDAY THRU 12Z FRIDAY...FRONT SLOWLY SHIFTS SOUTH WITH
SHOWERS ENDING AT MPV AND RUT. MAINLY VFR EXCEPT IFR/LIFR IN
MIST/FOG OVERNIGHT.
12Z FRIDAY THRU SUNDAY...MAINLY VFR EXCEPT MVFR IN PERIODS OF
SHOWERS MAINLY ACROSS RUT WITH SLOW-MOVING FRONTAL BOUNDARY.
OVERNIGHT FOG/MIST POTENTIAL 06-12Z TIMEFRAME ESPECIALLY AT SLK
AND MPV.
&&
.HYDROLOGY...
AS OF 437 AM EDT WEDNESDAY...ONCE AGAIN WE SAW ISOLATED STORMS
PRODUCE FLASH FLOODING ON TUESDAY. CONDITIONS FOR MORE FLASH
FLOODING WILL EXIST THIS AFTERNOON AND EVENING AND THE POTENTIAL
FOR FLASH FLOODING MAY ACTUALLY BE GREATER SIMPLY FOR THE FACT
THAT THERE WILL BE MORE STORMS AROUND THAN THE PAST COUPLE OF
DAYS. EXPECT SCATTERED TO NUMEROUS THUNDERSTORMS DEVELOPING OVER
THE AREA THIS AFTERNOON...ESPECIALLY FROM THE NORTHERN
ADIRONDACKS EASTWARD TO THE CONNECTICUT RIVER VALLEY. THE DEEP
LAYER OF MOISTURE IN THE ATMOSPHERE OVER THE REGION COMBINED WITH
SLOW MOVING STORMS SUGGESTS FLASH FLOODING IS POSSIBLE. THUS WILL
KEEP THE FLASH FLOOD WATCH IN PLACE. POTENTIAL IMPACTS INCLUDE
WASHED OUT AND FLOODED ROADS...FIELD FLOODING...RAPID RISES ON
SMALLER RIVERS AND STREAMS.
&&
.MARINE...
AS OF 436 AM EDT WEDNESDAY...ACTIVE WEATHER IS EXPECTED ACROSS
LAKE CHAMPLAIN TODAY THROUGH THIS EVENING. FIRST EXPECT STRONGER
WINDS OVER THE LAKE WITH SOUTH WINDS INCREASING INTO THE 20 TO 30
KNOT RANGE BY AFTERNOON AND NOT DECREASING UNTIL AFTER MIDNIGHT
TONIGHT. THESE WINDS ARE STRONGER THAN WHAT HAS BEEN FELT OVER
THE LAKE THE PAST FEW DAYS. THUS A LAKE WIND ADVISORY IS IN
EFFECT. IN ADDITION...EXPECT THUNDERSTORMS TO DEVELOP OVER
NORTHERN NEW YORK THIS AFTERNOON AND MOVE EAST ACROSS LAKE
CHAMPLAIN. BE AWARE THAT ANY STORMS WILL HAVE THE POTENTIAL TO
PRODUCE STRONG GUSTY WINDS AND AS WE HAVE SEEN THE PAST MONTH OR
SO...VERY HEAVY DOWNPOURS.
&&
.EQUIPMENT...
AS OF 436 AM EDT WEDNESDAY...THE KTYX RADAR IS DOWN UNTIL FURTHER
NOTICE. TECHS HAVE ORDERED PARTS...THOUGH RETURN TO SERVICE IS
UNKNOWN AT THIS TIME.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR VTZ001>012-
016>019.
NY...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR NYZ028>031-
034-035.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...EVENSON/JMG
SHORT TERM...EVENSON
LONG TERM...NEILES
AVIATION...NEILES/LOCONTO
HYDROLOGY...
MARINE...
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1009 AM EDT WED JUL 10 2013
.SYNOPSIS...
WATCH FOR SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS
DEVELOPING ACROSS MUCH OF THE NORTH COUNTRY THIS AFTERNOON AND
EVENING. ANY STORMS WILL HAVE THE POTENTIAL TO PRODUCE GUSTY
WINDS AND VERY HEAVY RAINFALL THAT COULD LEAD TO FLASH FLOODING.
THUS A FLASH FLOOD WATCH REMAINS IN EFFECT THIS AFTERNOON THROUGH
MIDNIGHT. THE THREAT FOR PRECIPITATION WILL BE LIMITED TO EASTERN
VERMONT ON THURSDAY AND THEN DRY WEATHER WITH SEASONAL
TEMPERATURES IS EXPECTED FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 1009 AM EDT WEDNESDAY...UPDATE TO POPS THROUGH THE DAY BASED
OFF CURRENT RADAR ACTIVITY AND BLEND OF AVAILABLE CAM MODEL
OUTPUT. STILL LOOKING MORE OR LESS AT 40/70% POPS ACROSS THE AREA
TODAY...BUT DETAILED CURRENT BAND PROGRESSING EAST ACROSS CENTRAL
NY MOVING INTO THE AREA A TAD BETTER AND AS RESOLVED QUITE WELL BY
LATEST HRRR DATA. REST OF FORECAST REMAINS MORE OR LESS IN GOOD
SHAPE. HAVE A GREAT DAY. PRIOR DISCUSSION FOLLOWS...
GOING FORECAST IN GOOD SHAPE AND NO CHANGES NEEDED AT THIS TIME.
THREAT FOR FLASH FLOODING AND STRONG GUSTY WINDS WILL REMAIN
ACROSS MUCH OF THE AREA THIS AFTERNOON AND EVENING. COMPOSITE
ANALYSIS SHOWS STRONGEST DYNAMIC SUPPORT AND DEEP LAYER SHEAR WILL
REMAIN ACROSS EASTERN CANADA THIS AFTERNOON AND EVENING AS LARGE
UPPER TROUGH MOVES INTO THE AREA. LATER THIS AFTERNOON
HOWEVER...THE SOUTHERN END OF THE STRONGER FLOW ALOFT...25 KNOTS
AT 850 MB AND 30 KNOTS AT 500 MB WILL MOVE ACROSS THE SOUTHERN
HALF OF VERMONT THIS AFTERNOON. THIS COMBINED WITH CONVECTIVE
AVAILABLE POTENTIAL ENERGY APPROACHING 1000 J/KG SUGGEST SOME
ORGANIZATION TO THE STORMS WILL EXIST. THUS LOOKING AT
PULSE/MULTICELL STORMS LATER THIS AFTERNOON AND EVENING WITH THE
AREA FROM THE NORTHERN ADIRONDACKS EASTWARD TO THE CONNECTICUT
RIVER VALLEY AS THE MAIN AREA OF CONCERN. AXIS OF HIGH
PRECIPITABLE WATER AIR...VALUES AROUND 2 INCHES...WILL NOSE RIGHT
UP INTO THE AREA. SO WITH STORM MOTIONS UNDER 15 KNOTS...THE
THREAT FOR HEAVY DOWNPOURS AND FLASH FLOODING WILL EXIST
ESPECIALLY SINCE THE AREA COVERAGE OF STORMS WILL BE GREATER THAN
THE PAST COUPLE OF DAYS. THUS GOING IDEA OF A FLASH FLOOD WATCH
FOR MOST OF THE AREA STILL LOOKS GOOD. IN ADDITION...FEEL WITH
SOME ORGANIZATION TO THE STORMS...THREAT FOR STRONG GUSTY WINDS
WILL EXIST. HAVE INCLUDED THE ENHANCED WORDING IN THE FORECAST FOR
THESE TWO THREATS. WE MAY SEE CLOUDS AND SPOTTY SHOWERS MOVE
ACROSS THE AREA THIS MORNING...BUT MAIN THREAT FOR STORMS WILL BE
AFTER 200 PM.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH FRIDAY/...
AS OF 437 AM EDT WEDNESDAY...ACTIVE WEATHER WITH STORMS
POTENTIALLY PRODUCING FLASH FLOODING WILL EXIST THROUGH MIDNIGHT
TONIGHT...THEN INTENSITY OF STORMS WILL WEAKEN OVERNIGHT AND MOVE
EAST OF THE AREA. COLD FRONT WILL BECOME PARALLEL TO THE UPPER
FLOW ON THURSDAY AND THUS THE FRONT WILL STILL HANG AROUND
EASTERN VERMONT FOR A CONTINUED CHANCE OF SHOWERS OR STORMS. HIGH
PRESSURE BUILDS IN LATE THURSDAY NIGHT AND FRIDAY FOR DRIER
WEATHER AND TEMPERATURES TRENDING SLIGHTLY BELOW NORMAL BY
FRIDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 437 AM EDT WEDNESDAY...THE PATTERN CHANGE TO A WESTERLY
FLOW OF DRIER WEATHER WILL PERSIST FRIDAY NIGHT THRU TUESDAY WITH
A WARMING TREND. HIGH PRESSURE WILL PERSIST THROUGH THE WEEKEND
INTO EARLY NEXT WEEK WITH UPPER LEVEL RIDGING AND A NW TO W FLOW
ALOFT. DO NOT SEE ANY SIGNIFICANT CHANCE FOR PRECIPITATION IN THE
EXTENDED. STILL LOTS OF UNCERTAINTY THAT FAR OUT...BUT GFS AND
NAM BOTH HINT AT SOME SHOWERS AROUND FRIDAY NIGHT AND SATURDAY.
HAVE LEANED TOWARDS DRIER ECMWF AT THIS POINT. TEMPERATURES WILL
START OUT SLIGHTLY BELOW NORMAL...BUT TREND BACK OVER NORMAL
TOWARDS THE END OF THE PERIOD.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
THROUGH 12Z THURSDAY...SOME MVFR CEILINGS THIS MORNING WITH LINE
OF LIGHT RAIN SHOWERS MOVING INTO WESTERN VERMONT CURRENTLY. WEAK
BOUNDARY WITH EVEN MORE HUMID AIR ASSOCIATED WITH APPROACHING
FRONTAL SYSTEM AROUND WITH CHANCE OF SHOWERS...PERHAPS A RUMBLE
OF THUNDER SO HAVE INCLUDED VCSH. OTHERWISE UNSTABLE AIR WILL BE
GENERATING WIDESPREAD SHOWERS AND THUNDERSTORMS BY 18Z OR SO.
HAVE INCLUDED VCTS AT ALL SITES AFTER 18Z WED. WINDS WILL BE
INCREASING FROM THE S-SW ON WED WITH 10-15 KNOTS SUSTAINED AND
GUSTS 15 TO 25 KNOTS ESPECIALLY BTV-MSS. AFTER 00Z SHOWERS AND
THUNDERSTORMS SHOULD DIE DOWN WITH LOSS OF DAYTIME HEATING.
OUTLOOK 12Z THURSDAY THROUGH SUNDAY...THU...MAINLY VFR AFTER SOME
EARLY MORNING SHOWERS AND FOG. FRI-SUN...MAINLY VFR WITH
NORTHERLY FLOW AND HIGH PRESSURE.
&&
.HYDROLOGY...
AS OF 437 AM EDT WEDNESDAY...ONCE AGAIN WE SAW ISOLATED STORMS
PRODUCE FLASH FLOODING ON TUESDAY. CONDITIONS FOR MORE FLASH
FLOODING WILL EXIST THIS AFTERNOON AND EVENING AND THE POTENTIAL
FOR FLASH FLOODING MAY ACTUALLY BE GREATER SIMPLY FOR THE FACT
THAT THERE WILL BE MORE STORMS AROUND THAN THE PAST COUPLE OF
DAYS. EXPECT SCATTERED TO NUMEROUS THUNDERSTORMS DEVELOPING OVER
THE AREA THIS AFTERNOON...ESPECIALLY FROM THE NORTHERN
ADIRONDACKS EASTWARD TO THE CONNECTICUT RIVER VALLEY. THE DEEP
LAYER OF MOISTURE IN THE ATMOSPHERE OVER THE REGION COMBINED WITH
SLOW MOVING STORMS SUGGESTS FLASH FLOODING IS POSSIBLE. THUS WILL
KEEP THE FLASH FLOOD WATCH IN PLACE. POTENTIAL IMPACTS INCLUDE
WASHED OUT AND FLOODED ROADS...FIELD FLOODING...RAPID RISES ON
SMALLER RIVERS AND STREAMS.
&&
.MARINE...
AS OF 436 AM EDT WEDNESDAY...ACTIVE WEATHER IS EXPECTED ACROSS
LAKE CHAMPLAIN TODAY THROUGH THIS EVENING. FIRST EXPECT STRONGER
WINDS OVER THE LAKE WITH SOUTH WINDS INCREASING INTO THE 20 TO 30
KNOT RANGE BY AFTERNOON AND NOT DECREASING UNTIL AFTER MIDNIGHT
TONIGHT. THESE WINDS ARE STRONGER THAN WHAT HAS BEEN FELT OVER
THE LAKE THE PAST FEW DAYS. THUS A LAKE WIND ADVISORY IS IN
EFFECT. IN ADDITION...EXPECT THUNDERSTORMS TO DEVELOP OVER
NORTHERN NEW YORK THIS AFTERNOON AND MOVE EAST ACROSS LAKE
CHAMPLAIN. BE AWARE THAT ANY STORMS WILL HAVE THE POTENTIAL TO
PRODUCE STRONG GUSTY WINDS AND AS WE HAVE SEEN THE PAST MONTH OR
SO...VERY HEAVY DOWNPOURS.
&&
.EQUIPMENT...
AS OF 436 AM EDT WEDNESDAY...THE KTYX RADAR IS DOWN UNTIL FURTHER
NOTICE. TECHS HAVE ORDERED PARTS...THOUGH RETURN TO SERVICE IS
UNKNOWN AT THIS TIME.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...FLASH FLOOD WATCH THROUGH THIS EVENING FOR VTZ001>012-016>019.
NY...FLASH FLOOD WATCH THROUGH THIS EVENING FOR NYZ028>031-034-035.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...JMG/EVENSON
SHORT TERM...EVENSON
LONG TERM...NEILES
AVIATION...NEILES
HYDROLOGY..EVENSON
MARINE...EVENSON
EQUIPMENT...BTV
AREA FORECAST DISCUSSION
NWS RALEIGH NC
225 PM EDT WED JUL 10 2013
.SYNOPSIS...
A SERIES OF WEAK DISTURBANCES ALOFT WILL CROSS THE MIDDLE ATLANTIC
REGION THROUGH TONIGHT. A STRONGER UPPER LEVEL TROUGH AND ASSOCIATED
SURFACE COLD FRONT WILL MOVE INTO THE REGION LATE THURSDAY INTO
FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 AM WEDNESDAY...
ANOTHER UNSETTLED AFTERNOON AND EVENING EXPECTED ACROSS CENTRAL NC
WITH A CONSIDERABLE AMOUNT OF CLOUDINESS AND A COUPLE OF FAVORED
REGIONS FOR CONVECTION. MORNING UPPER AIR ANALYSIS AND SATELLITE
IMAGERY DEPICTS A LINGERING SHEAR AXIS DRAPED NORTHEAST TO SOUTHWEST
FROM KECG TO KGSB TO KLBT. THE RAP SUGGESTS THIS FEATURE WILL DRIFT
EAST SLIGHTLY AND WOULD FAVOR CONVECTION ACROSS THE EASTERN THIRD OF
THE RAH CWA. ANOTHER REGION FAVORED FOR CONVECTION WILL BE THE
ACROSS THE FOOTHILLS OF NC/VA WHERE AN APPROACHING TROUGH AXIS WILL
INITIATE CONVECTION THAT IS PROGGED BY MANY CONVECTION ALLOWING
MODELS TO DEVELOP INTO A MORE LINEAR/MULTI-CELL SYSTEM THAT WILL
LIKELY MOVE INTO WESTERN/NORTHERN PARTS OF THE RAH CWA LATE THIS
AFTERNOON AND EVENING. THE AIR MASS ACROSS CENTRAL NC IS WET WITH PW
VALUES AROUND 1.75 INCHES. MODERATE INSTABILITY WITH UNIMPRESSIVE
LAPSE RATES IN A WEAK SOUTHWESTERLY FLOW SHOULD LIMIT THE SEVERE
THREAT TO A FEW STORMS WITH DOWNBURST WINDS FROM PRECIP LOADING WITH
LOCALIZED FLOODING IN SLOW MOVING STORMS A MORE NOTEWORTHY THREAT.
CURRENT FORECAST OF HIGHS IN THE UPPER 80S TO AROUND 90 AND LOWS IN
THE LOWER 70S LOOKS GOOD. -BLAES
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
AS OF 320 AM WEDNESDAY...
THE FLOW ALOFT WILL UNDERGO SIGNIFICANT AMPLIFICATION THIS PERIOD...
HIGHLIGHTED FOR CENTRAL NC BY A SHARP...POSITIVELY TILTED TROUGH
AXIS FROM EASTERN CANADA SSW TO THE LOWER MS VALLEY. MOIST SW FLOW
ALOFT AND STRONG QG FORCING FOR ASCENT ASSOCIATED WITH THE
TROUGH/UPPER JET...IN ADDITION TO THE THU NIGHT ARRIVAL OF AN
ACCOMPANYING SURFACE COLD FRONT...WILL YIELD NUMEROUS TO WIDESPREAD
SHOWERS AND STORMS THU AFTERNOON AND THROUGHOUT THE NIGHT...
INCLUDING A PROBABLE LOOSELY-ORGANIZED LINE OF STORMS...WITH HEAVY
RAIN AND A FEW STRONG WIND GUSTS...AHEAD OF/ALONG THE FRONT. A
WIDESPREAD SOAKING RAIN OF ONE HALF TO ONE INCH IS LIKELY...WITH
LOCALLY MUCH HIGHER AMOUNTS WHERE THE (EFFECTIVE) FRONTAL CONVECTION
OVERLAPS EARLIER AFTERNOON AND EVENING WARM-SECTOR STORMS. SIMILAR
TEMPERATURES TO PREVIOUS DAYS...GENERALLY UPPER 80S TO AROUND
90...AND LOWER 70S.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 150 PM WEDNESDAY...
THE LONG TERM WILL BE CHARACTERIZED BY A FRONTAL ZONE CROSSING THE
AREA AND STALLING IN THE VICINITY OF THE COAST BEFORE RETROGRADING
BACK ACROSS OUR AREA THIS WEEKEND. AN EXTENDED PERIOD OF WET AND
UNSETTLED WEATHER CAN BE EXPECTED THROUGH EARLY NEXT WEEK.
CONSIDERING ALL THE ANTECEDENT RAINFALL WE HAVE HAD ACROSS CENTRAL
NORTH CAROLINA...AND PRECIPITABLE WATER VALUES OVER 2 INCHES
THROUGHOUT THE PERIOD...THE POTENTIAL FOR FLASH FLOODING WILL BE
HIGH AND THE BIGGEST CONCERN FOR THIS FORECAST PERIOD. QPF FOR THIS
PERIOD WILL MOST LIKELY BE A WIDESPREAD 1.5 TO 2 INCHES WITH SOME
LOCALES EXPERIENCING HIGHER AMOUNTS IN TRAINING OR HEAVIER
THUNDERSTORMS.
THE FRONT WILL CROSS CENTRAL NC ON FRIDAY...DRIVEN BY A MID-ATLANTIC
SURFACE LOW. THERE IS SOME UNCERTAINTY IN TIMING. THE LATEST GFS
SHOWS A SLOWER PROGRESSION OF THE FRONT BUT MAY HAVE SOME ISSUES
WITH SOME OF THE MESO-SCALE FEATURES THAT MAY FORM IN THE MEANTIME.
THE NAM IS MUCH MORE PROGRESSIVE WITH THE FRONT BRINGING IT THROUGH
THE CWA BEFORE 12Z FRIDAY WHILE THE GFS SLOWS THE FRONT AND HAS IT
LINGER ACROSS THE AREA THROUGH 18Z. EITHER WAY MUCH OF THE CWA IF
NOT ALL WILL BE WET WITH INCREASING CHANCES IN THE SOUTHEAST LATER
IN THE DAY AS THE FRONT SETTLES OVER THE COASTAL PLAIN. THE FRONT
WILL STAY SOUTHEAST OF THE AREA FOR MOST OF THE DAY ON SATURDAY
BEFORE THE BERMUDA HIGH BEGINS TO SLOWLY WORK BACK TO THE WEST AND
BEGIN A SLOW RETROGRADE OF THE FRONT LATE SATURDAY INTO SUNDAY
MORNING. THE X FACTOR HERE WILL BE REMNANT MOISTURE ASSOCIATED
CHANTAL WITH WHAT WILL MOST LIKELY BE CLASSIFIED AS A TROPICAL
DEPRESSION AT THAT TIME. THIS COULD BRING MOISTURE BACK TO THE NORTH
AND WEST A LITTLE QUICKER THAN THE CURRENT GFS SHOWS. TEMPERATURES
DURING THIS PERIOD WILL BE IN THE MID 80S FOR HIGHS WITH LOWS IN THE
UPPER 60S NORTHWEST TO LOWER 70S SOUTHEAST.
ON SUNDAY SOUTHEASTERLY FLOW WILL RETURN TO THE AREA (PERHAPS LATER
SUNDAY IN THE TRIAD) AND BEGIN A SLIGHT WARMING TREND WITH CONTINUED
STRONG MOISTURE ADVECTION THROUGH THE DAY ON SUNDAY BEFORE BECOMING
MORE EASTERLY AND SLIGHTLY LESS WET BUT PW VALUES WILL STILL HOVER
AROUND 2 INCHES THROUGH TUESDAY. GRADUALLY THE HIGH IN THE WESTERN
ATLANTIC WILL BUILD BACK IN AND SLOWLY HELP TO DRY THINGS OUT
POSSIBLY BY WEDNESDAY. THICKNESS VALUES SUPPORT MAXIMUM TEMPERATURES
FOR THIS PERIOD WILL GRADUALLY RISE FROM THE MID 80S TO NEAR 90 (AT
LEAST IN THE SOUTHEAST) BY WEDNESDAY. LOWS GENERALLY IN THE UPPER
60S TO LOW 70S.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 225 PM TUESDAY...
LITTLE CHANGE IN THE WEATHER PATTERN DURING THE PERIOD WITH A
FAIRLY TYPICAL ALTHOUGH PERHAPS MORE ACTIVE MID SUMMER WEATHER
PATTERN WITH A WARM AND HUMID AIRMASS. SCT CONVECTION WILL CONTINUE
TO DEVELOP THIS AFTERNOON...ESPECIALLY ACROSS THE COASTAL PLAIN
AFFECTING KFAY AND KRWI. ANOTHER AREA OF CONVECTION DEVELOPING
ACROSS THE MOUNTAINS WILL LIKELY MOVE ACROSS THE PIEDMONT THIS
EVENING AFFECTING KINT/KGSO AND PERHAPS TOWARD THE COASTAL PLAIN
LATE THIS EVENING. OUTSIDE OF THUNDERSTORMS...VFR CONDITIONS ARE
ANTICIPATED THIS AFTERNOON AND EVENING. OVERNIGHT TOWARD DAYBREAK
ANOTHER ROUND OF IFR/LIFR STRATUS IS LIKELY. THE REDUCED CEILINGS
WILL GRADUALLY LIFT DURING THE MORNING AND BECOME VFR BEFORE NOON.
ADDITIONAL CONVECTION...PERHAPS WITH EVEN GREATER COVERAGE IS LIKELY
THURSDAY AFTERNOON AND EVENING.
LOOKING FURTHER AHEAD...WEATHER CONDITIONS WILL LIKELY FEATURE A
SIMILAR PATTERN OF SHOWERS AND THUNDERSTORMS...MOST NUMEROUS DURING
THE AFTERNOON AND EVENING WITH CONSIDERABLE CLOUDS AND PERIODS OF
LOW CEILINGS...ESPECIALLY IN THE EARLY MORNING.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MWS
NEAR TERM...BLAES
SHORT TERM...MWS
LONG TERM...ELLIS
AVIATION...BLAES
AREA FORECAST DISCUSSION
NWS RALEIGH NC
151 PM EDT WED JUL 10 2013
.SYNOPSIS...
A SERIES OF WEAK DISTURBANCES ALOFT WILL CROSS THE MIDDLE ATLANTIC
REGION THROUGH TONIGHT. A STRONGER UPPER LEVEL TROUGH AND ASSOCIATED
SURFACE COLD FRONT WILL MOVE INTO THE REGION LATE THURSDAY INTO
FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 AM WEDNESDAY...
ANOTHER UNSETTLED AFTERNOON AND EVENING EXPECTED ACROSS CENTRAL NC
WITH A CONSIDERABLE AMOUNT OF CLOUDINESS AND A COUPLE OF FAVORED
REGIONS FOR CONVECTION. MORNING UPPER AIR ANALYSIS AND SATELLITE
IMAGERY DEPICTS A LINGERING SHEAR AXIS DRAPED NORTHEAST TO SOUTHWEST
FROM KECG TO KGSB TO KLBT. THE RAP SUGGESTS THIS FEATURE WILL DRIFT
EAST SLIGHTLY AND WOULD FAVOR CONVECTION ACROSS THE EASTERN THIRD OF
THE RAH CWA. ANOTHER REGION FAVORED FOR CONVECTION WILL BE THE
ACROSS THE FOOTHILLS OF NC/VA WHERE AN APPROACHING TROUGH AXIS WILL
INITIATE CONVECTION THAT IS PROGGED BY MANY CONVECTION ALLOWING
MODELS TO DEVELOP INTO A MORE LINEAR/MULTI-CELL SYSTEM THAT WILL
LIKELY MOVE INTO WESTERN/NORTHERN PARTS OF THE RAH CWA LATE THIS
AFTERNOON AND EVENING. THE AIR MASS ACROSS CENTRAL NC IS WET WITH PW
VALUES AROUND 1.75 INCHES. MODERATE INSTABILITY WITH UNIMPRESSIVE
LAPSE RATES IN A WEAK SOUTHWESTERLY FLOW SHOULD LIMIT THE SEVERE
THREAT TO A FEW STORMS WITH DOWNBURST WINDS FROM PRECIP LOADING WITH
LOCALIZED FLOODING IN SLOW MOVING STORMS A MORE NOTEWORTHY THREAT.
CURRENT FORECAST OF HIGHS IN THE UPPER 80S TO AROUND 90 AND LOWS IN
THE LOWER 70S LOOKS GOOD. -BLAES
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
AS OF 320 AM WEDNESDAY...
THE FLOW ALOFT WILL UNDERGO SIGNIFICANT AMPLIFICATION THIS PERIOD...
HIGHLIGHTED FOR CENTRAL NC BY A SHARP...POSITIVELY TILTED TROUGH
AXIS FROM EASTERN CANADA SSW TO THE LOWER MS VALLEY. MOIST SW FLOW
ALOFT AND STRONG QG FORCING FOR ASCENT ASSOCIATED WITH THE
TROUGH/UPPER JET...IN ADDITION TO THE THU NIGHT ARRIVAL OF AN
ACCOMPANYING SURFACE COLD FRONT...WILL YIELD NUMEROUS TO WIDESPREAD
SHOWERS AND STORMS THU AFTERNOON AND THROUGHOUT THE NIGHT...
INCLUDING A PROBABLE LOOSELY-ORGANIZED LINE OF STORMS...WITH HEAVY
RAIN AND A FEW STRONG WIND GUSTS...AHEAD OF/ALONG THE FRONT. A
WIDESPREAD SOAKING RAIN OF ONE HALF TO ONE INCH IS LIKELY...WITH
LOCALLY MUCH HIGHER AMOUNTS WHERE THE (EFFECTIVE) FRONTAL CONVECTION
OVERLAPS EARLIER AFTERNOON AND EVENING WARM-SECTOR STORMS. SIMILAR
TEMPERATURES TO PREVIOUS DAYS...GENERALLY UPPER 80S TO AROUND
90...AND LOWER 70S.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 150 PM WEDNESDAY...
THE LONG TERM WILL BE CHARACTERIZED BY A FRONTAL ZONE CROSSING THE
AREA AND STALLING IN THE VICINITY OF THE COAST BEFORE RETROGRADING
BACK ACROSS OUR AREA THIS WEEKEND. AN EXTENDED PERIOD OF WET AND
UNSETTLED WEATHER CAN BE EXPECTED THROUGH EARLY NEXT WEEK.
CONSIDERING ALL THE ANTECEDENT RAINFALL WE HAVE HAD ACROSS CENTRAL
NORTH CAROLINA...AND PRECIPITABLE WATER VALUES OVER 2 INCHES
THROUGHOUT THE PERIOD...THE POTENTIAL FOR FLASH FLOODING WILL BE
HIGH AND THE BIGGEST CONCERN FOR THIS FORECAST PERIOD. QPF FOR THIS
PERIOD WILL MOST LIKELY BE A WIDESPREAD 1.5 TO 2 INCHES WITH SOME
LOCALES EXPERIENCING HIGHER AMOUNTS IN TRAINING OR HEAVIER
THUNDERSTORMS.
THE FRONT WILL CROSS CENTRAL NC ON FRIDAY...DRIVEN BY A MID-ATLANTIC
SURFACE LOW. THERE IS SOME UNCERTAINTY IN TIMING. THE LATEST GFS
SHOWS A SLOWER PROGRESSION OF THE FRONT BUT MAY HAVE SOME ISSUES
WITH SOME OF THE MESO-SCALE FEATURES THAT MAY FORM IN THE MEANTIME.
THE NAM IS MUCH MORE PROGRESSIVE WITH THE FRONT BRINGING IT THROUGH
THE CWA BEFORE 12Z FRIDAY WHILE THE GFS SLOWS THE FRONT AND HAS IT
LINGER ACROSS THE AREA THROUGH 18Z. EITHER WAY MUCH OF THE CWA IF
NOT ALL WILL BE WET WITH INCREASING CHANCES IN THE SOUTHEAST LATER
IN THE DAY AS THE FRONT SETTLES OVER THE COASTAL PLAIN. THE FRONT
WILL STAY SOUTHEAST OF THE AREA FOR MOST OF THE DAY ON SATURDAY
BEFORE THE BERMUDA HIGH BEGINS TO SLOWLY WORK BACK TO THE WEST AND
BEGIN A SLOW RETROGRADE OF THE FRONT LATE SATURDAY INTO SUNDAY
MORNING. THE X FACTOR HERE WILL BE REMNANT MOISTURE ASSOCIATED
CHANTAL WITH WHAT WILL MOST LIKELY BE CLASSIFIED AS A TROPICAL
DEPRESSION AT THAT TIME. THIS COULD BRING MOISTURE BACK TO THE NORTH
AND WEST A LITTLE QUICKER THAN THE CURRENT GFS SHOWS. TEMPERATURES
DURING THIS PERIOD WILL BE IN THE MID 80S FOR HIGHS WITH LOWS IN THE
UPPER 60S NORTHWEST TO LOWER 70S SOUTHEAST.
ON SUNDAY SOUTHEASTERLY FLOW WILL RETURN TO THE AREA (PERHAPS LATER
SUNDAY IN THE TRIAD) AND BEGIN A SLIGHT WARMING TREND WITH CONTINUED
STRONG MOISTURE ADVECTION THROUGH THE DAY ON SUNDAY BEFORE BECOMING
MORE EASTERLY AND SLIGHTLY LESS WET BUT PW VALUES WILL STILL HOVER
AROUND 2 INCHES THROUGH TUESDAY. GRADUALLY THE HIGH IN THE WESTERN
ATLANTIC WILL BUILD BACK IN AND SLOWLY HELP TO DRY THINGS OUT
POSSIBLY BY WEDNESDAY. THICKNESS VALUES SUPPORT MAXIMUM TEMPERATURES
FOR THIS PERIOD WILL GRADUALLY RISE FROM THE MID 80S TO NEAR 90 (AT
LEAST IN THE SOUTHEAST) BY WEDNESDAY. LOWS GENERALLY IN THE UPPER
60S TO LOW 70S.
&&
.AVIATION /11Z WEDNESDAY THROUGH SUNDAY/...
AS OF 725 AM TUESDAY...
PERSISTENCE. CONTINUED VERY HUMID SOUTHERLY FLOW AROUND BERMUDA HIGH
PRESSURE WILL MAINTAIN A FAMILIAR PATTERN CONSISTING OF EARLY
MORNING (V)LIFR CEILINGS THAT WILL GRADUALLY LIFT AND SCATTER
THROUGH MVFR RANGE...TO VFR...THROUGH 16-18Z. VFR CONDITIONS SHOULD
THEN PREVAIL OUTSIDE OF SCATTERED SHOWERS AND STORMS THIS AFTERNOON
AND EVENING...MOST LIKELY AT KFAY/KRWI/KRDU BETWEEN 17-22Z...AND AT
TRIAD TERMINALS (KGSO/KINT) BETWEEN 21Z-02Z. SOME CONVECTION IS
LIKELY TO LINGER OVERNIGHT...IN RESPONSE TO AN APPROACHING STRONG
UPPER LEVEL TROUGH AND ASSOCIATED LIFT. LIFR CEILINGS SHOULD THEN
REDEVELOP IN THE VERY HUMID REGIME LATE TONIGHT-EARLY THU.
OUTLOOK...
MORE OF THE SAME EXPECTED THROUGH THE WEEKEND...WITH SHOWER AND
STORM COVERAGE MAXIMIZED LATE THU AND THU NIGHT...AND THROUGH FRI AT
EASTERN TAF SITES...OWING TO THE APPROACH AND PASSAGE OF AN UPPER
LEVEL TROUGH AND SURFACE COLD FRONT.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MWS
NEAR TERM...BLAES
SHORT TERM...MWS
LONG TERM...ELLIS
AVIATION...MWS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1045 AM EDT WED JUL 10 2013
.SYNOPSIS...
A SERIES OF WEAK DISTURBANCES ALOFT WILL CROSS THE MIDDLE ATLANTIC
REGION THROUGH TONIGHT. A STRONGER UPPER LEVEL TROUGH AND ASSOCIATED
SURFACE COLD FRONT WILL MOVE INTO THE REGION LATE THURSDAY INTO
FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 AM WEDNESDAY...
ANOTHER UNSETTLED AFTERNOON AND EVENING EXPECTED ACROSS CENTRAL NC
WITH A CONSIDERABLE AMOUNT OF CLOUDINESS AND A COUPLE OF FAVORED
REGIONS FOR CONVECTION. MORNING UPPER AIR ANALYSIS AND SATELLITE
IMAGERY DEPICTS A LINGERING SHEAR AXIS DRAPED NORTHEAST TO SOUTHWEST
FROM KECG TO KGSB TO KLBT. THE RAP SUGGESTS THIS FEATURE WILL DRIFT
EAST SLIGHTLY AND WOULD FAVOR CONVECTION ACROSS THE EASTERN THIRD OF
THE RAH CWA. ANOTHER REGION FAVORED FOR CONVECTION WILL BE THE
ACROSS THE FOOTHILLS OF NC/VA WHERE AN APPROACHING TROUGH AXIS WILL
INITIATE CONVECTION THAT IS PROGGED BY MANY CONVECTION ALLOWING
MODELS TO DEVELOP INTO A MORE LINEAR/MULTI-CELL SYSTEM THAT WILL
LIKELY MOVE INTO WESTERN/NORTHERN PARTS OF THE RAH CWA LATE THIS
AFTERNOON AND EVENING. THE AIR MASS ACROSS CENTRAL NC IS WET WITH PW
VALUES AROUND 1.75 INCHES. MODERATE INSTABILITY WITH UNIMPRESSIVE
LAPSE RATES IN A WEAK SOUTHWESTERLY FLOW SHOULD LIMIT THE SEVERE
THREAT TO A FEW STORMS WITH DOWNBURST WINDS FROM PRECIP LOADING WITH
LOCALIZED FLOODING IN SLOW MOVING STORMS A MORE NOTEWORTHY THREAT.
CURRENT FORECAST OF HIGHS IN THE UPPER 80S TO AROUND 90 AND LOWS IN
THE LOWER 70S LOOKS GOOD. -BLAES
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
AS OF 320 AM WEDNESDAY...
THE FLOW ALOFT WILL UNDERGO SIGNIFICANT AMPLIFICATION THIS PERIOD...
HIGHLIGHTED FOR CENTRAL NC BY A SHARP...POSITIVELY TILTED TROUGH
AXIS FROM EASTERN CANADA SSW TO THE LOWER MS VALLEY. MOIST SW FLOW
ALOFT AND STRONG QG FORCING FOR ASCENT ASSOCIATED WITH THE
TROUGH/UPPER JET...IN ADDITION TO THE THU NIGHT ARRIVAL OF AN
ACCOMPANYING SURFACE COLD FRONT...WILL YIELD NUMEROUS TO WIDESPREAD
SHOWERS AND STORMS THU AFTERNOON AND THROUGHOUT THE NIGHT...
INCLUDING A PROBABLE LOOSELY-ORGANIZED LINE OF STORMS...WITH HEAVY
RAIN AND A FEW STRONG WIND GUSTS...AHEAD OF/ALONG THE FRONT. A
WIDESPREAD SOAKING RAIN OF ONE HALF TO ONE INCH IS LIKELY...WITH
LOCALLY MUCH HIGHER AMOUNTS WHERE THE (EFFECTIVE) FRONTAL CONVECTION
OVERLAPS EARLIER AFTERNOON AND EVENING WARM-SECTOR STORMS. SIMILAR
TEMPERATURES TO PREVIOUS DAYS...GENERALLY UPPER 80S TO AROUND
90...AND LOWER 70S.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 305 AM WEDNESDAY...
A COUPLE POTENTIAL HAZARDS IN THE EXTENDED PERIOD OF THE FORECAST
INCLUDING THE FLASH FLOODING POTENTIAL AND THE FORECAST OF CURRENT
CHANTAL.
FIRST... ANTECEDENT CONDITIONS CONTINUE PRIMED FOR FLASH FLOODING.
IT APPEARS THAT THE FLASH FLOOD THREAT WILL BE SHIFTING TO THE SE
QUADRANT OF NORTH CAROLINA BY FRIDAY. MODELS ARE IN GOOD AGREEMENT
IN PLACING THE COLD FRONT OVER CENTRAL NC 12Z FRIDAY... GRADUALLY
DRIFTING SE INTO SE NC DURING THE DAY. THIS SUPPORTS THE HEAVIEST
QPF IN A SW-NE AXIS ACROSS THE SANDHILLS INTO THE COASTAL PLAIN...
SLIDING SE WITH TIME FRIDAY. THIS FORECAST IS MODERATE TO HIGH
CONFIDENCE GIVEN SUPPORT FROM TRENDS AND ENSEMBLE FORECASTS AS WELL.
THEREFORE... WE WILL CONTINUE TO LOWER POP IN THE NW... AND CONTINUE
WITH SHOWERS AND THUNDERSTORMS LIKELY IN THE SE... WITH MORE
SCATTERED SHOWERS AND THUNDERSTORMS IN THE MIDDLE OF THE STATE. QPF
OF AN INCH OR SO APPEARS REASONABLE FROM 12Z FRIDAY TO 12Z SATURDAY
IN THE SE... WITH LOCALLY 2 INCHES IN THE STRONGER STORMS FRIDAY
AFTERNOON. LESSER QPF WITH LESS THAN 0.25 EXPECTED IN THE NW
PIEDMONT. PARTLY TO MOSTLY CLOUDY SKIES FRIDAY NIGHT... WITH
ISOLATED ACTIVITY IN THE NW... AND SCATTERED IN THE SE. HIGHS FRIDAY
IN THE LOWER TO MID 80S. LOWS FRIDAY NIGHT UPPER 60S TO LOWER 70S.
SATURDAY THROUGH TUESDAY... A TRANSITION PERIOD WITH THE FATE OF
CHANTAL ESSENTIALLY TO BE DETERMINED. AFTER THE STALLED BOUNDARY
ESSENTIALLY WASHES OUT OVER SE NC THIS WEEKEND... WITH AT LEAST
SCATTERED SHOWERS AND THUNDERSTORMS BOTH SAT-SUN... MUCH OF NEXT
WEEK APPEARS THAT IT WILL BE MORE MID-JULY LIKE... AS MODELS DEPICT
ABOVE NORMAL HEIGHTS OVER MOST OF THE U.S. HOWEVER... A LINGERING
WEAKNESS EARLY IN THE WEEK WILL LIKELY SPELL A CONTINUATION OF
SCATTERED DIURNALLY DRIVEN SHOWERS AND THUNDERSTORMS OVER OUR REGION
MONDAY AND TUESDAY.
A WILD CARD CONTINUES TO BE THE FATE OF CURRENT TROPICAL STORM
CHANTAL. OBVIOUSLY THIS WILL BE MONITORED CLOSELY AND THE FORECASTS
FROM THE NHC WILL BE FOLLOWED EXPLICITLY. IN THOSE REGARDS... IF
THE SYSTEM AFFECTS OUR REGION DIRECTLY OR INDIRECTLY... IT WOULD
MOST LIKELY BE EARLY NEXT WEEK.
&&
.AVIATION /11Z WEDNESDAY THROUGH SUNDAY/...
AS OF 725 AM TUESDAY...
PERSISTENCE. CONTINUED VERY HUMID SOUTHERLY FLOW AROUND BERMUDA HIGH
PRESSURE WILL MAINTAIN A FAMILIAR PATTERN CONSISTING OF EARLY
MORNING (V)LIFR CEILINGS THAT WILL GRADUALLY LIFT AND SCATTER
THROUGH MVFR RANGE...TO VFR...THROUGH 16-18Z. VFR CONDITIONS SHOULD
THEN PREVAIL OUTSIDE OF SCATTERED SHOWERS AND STORMS THIS AFTERNOON
AND EVENING...MOST LIKELY AT KFAY/KRWI/KRDU BETWEEN 17-22Z...AND AT
TRIAD TERMINALS (KGSO/KINT) BETWEEN 21Z-02Z. SOME CONVECTION IS
LIKELY TO LINGER OVERNIGHT...IN RESPONSE TO AN APPROACHING STRONG
UPPER LEVEL TROUGH AND ASSOCIATED LIFT. LIFR CEILINGS SHOULD THEN
REDEVELOP IN THE VERY HUMID REGIME LATE TONIGHT-EARLY THU.
OUTLOOK...
MORE OF THE SAME EXPECTED THROUGH THE WEEKEND...WITH SHOWER AND
STORM COVERAGE MAXIMIZED LATE THU AND THU NIGHT...AND THROUGH FRI AT
EASTERN TAF SITES...OWING TO THE APPROACH AND PASSAGE OF AN UPPER
LEVEL TROUGH AND SURFACE COLD FRONT.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MWS
NEAR TERM...BLAES
SHORT TERM...MWS
LONG TERM...BADGETT
AVIATION...MWS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
608 PM CDT THU JUL 11 2013
.UPDATE...
ISSUED AT 610 PM CDT THU JUL 11 2013
THERE ARE A FEW STORMS IN THE SE FA...SO WILL ADD SOME LOW POPS
THROUGH THIS EVENING HERE. OTHERWISE...THE FORECAST IS IN GOOD
SHAPE WITH THE POTENTIAL FOR SHOWERS AND STORMS INCREASING AFTER
06Z. AN MCS IS STARTING TO DEVELOP IN WESTERN ND...AND AS THE LLJ
INCREASES OVERNIGHT EXPECT A FORWARD PROPAGATING MCS OVER NIGHT.
EXPECT THE BEST CHANCES FOR CONVECTION IN THE NORTH...ALTHOUGH IT
IS INTERESTING TO NOT THE HRRR ACTUALLY MOVES THE COMPLEX MORE
EASTERLY...BUT FEEL THIS IS A BIT TOO FAR SOUTH. WE WILL CONTINUE
TO MONITOR THIS POTENTIAL OVERNIGHT...WITH THE MAIN SEVERE
THREAT LIKELY FROM STRONG WINDS IF A BOW ECHO CAN DEVELOP WITH
HIGH DCAPES IN PLACE.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 303 PM CDT THU JUL 11 2013
PRIMARY FORECAST CHALLENGE FOR TONIGHT WILL BE CAP STRENGTH AND
TIMING OF CONVECTIVE INITIATION...IF ANY. MODELS IN VERY GOOD
AGREEMENT SHOWING 14 DEG H700 TEMP AXIS FROM RAPID CITY SD THROUGH
HALLOCK MN AREA. WHERE MODELS DIFFER IS INITIATION AND PLACEMENT
OF CONVECTION. GOING WITH A MODEL BLEND FOR THIS FORECAST...BUT
LEANING TOWARD WRF SOLUTION WHICH KEEPS INITIAL CONVECTION FURTHER
NORTH IS SLIGHTLY COOLER MID LEVEL AIRMASS.
TONIGHT...NOSE OF A 50 KT H850 JET WILL BEGIN PUSHING INTO SOUTH
CENTRAL SD AROUND 06Z...WITH 30 KT TO 40 KT INTO DVL BASIN BY
03Z. QUESTION IS WILL THIS BE STRONG ENOUGH TO HELP ERODE CAP.
CERTAINLY PROVIDING THE JUICE WITH DECENT MOISTURE TRANSPORT
EVIDENT ON MESO ANALYSIS. ANOTHER DIFFERENCE IS THE GFS SHOWING A
POCKET OF COOLER AIR OVER NORTHEAST NORTH DAKOTA AROUND 06Z. ATTM
THINK THIS IS MAINLY DUE TO CONVECTIVE FEEDBACK AND HAVE REDUCED
LIKELIES IN THIS AREA. HOWEVER...WITH STRENGTHENING LLJ AND
POSSIBLE COLD POOL ALOFT WILL MAINTAIN 50 POPS. SPC MOVED SLIGHTLY
EAST THE SLIGHT RISK AREA...STILL MAINLY IN TOWNER AND WESTERN
BENSON COUNTIES. BETTER THREAT WILL BE ACROSS CENTRAL ND...AND
WILL NOT INCREASE POPS SIGNIFICANTLY PRIOR TO 06Z.
TOMORROW AND TOMORROW NIGHT...SFC TROUGH MOVES INTO EASTERN CWA IN
AFTN HOURS. CAPPING ENVIRONMENT WILL AGAIN BE AN ISSUE...ALONG
WITH ANY ASSOCIATED CLOUD COVER FROM CONVECTION TONIGHT THAT WILL
INHIBIT ABILITY TO HEAT OUT TOMORROW. HAVING SAID THAT...WITH SFC
TROUGH PUSHING INTO SOUTHEASTERN ZONES DURING MAX HEATING...WILL
GO WITH LIKELY POPS LATE AFTN/EARLY EVENING. SEVERE POTENTIAL WILL
BE DEPENDENT ON CAP/SOLAR HEATING.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 303 PM CDT THU JUL 11 2013
CENTRAL VALLEY SHOULD SEE A BREAK IN ACTIVITY ON SAT HOWEVER
DEPARTING TROUGH WILL BEGIN TO STALL KEEP POTENTIAL FOR CONVECTION
IN SOUTHEASTERN ZONES THROUGH THE WEEKEND.
FORECAST AREA TO REMAIN IN RELATIVELY ZONAL FLOW THROUGH THE PERIOD.
WHILE WIDESPREAD AREAS OF SHRA/TSRA ARE NOT EXPECTED SUBTLE MID
LEVEL DISTURBANCES INTERACTING WITH LOW LEVEL BOUNDARIES COULD
RESULT IN CONVECTION NEARLY EACH DAY OVER SOME PORTION OF THE
FORECAST AREA. UNFORTUNATELY MODELS DIFFER ON BOUNDARY LOCATIONS AND
TIMING OF WAVE PASSAGE ALWAYS DIFFICULT IN ZONAL FLOW PATTERNS. WILL
CONTINUE TO FOLLOW BROAD LOW TO MID RANGE POPS THROUGH PERIOD WITH
TEMPERATURES AT OR ABOVE AVERAGE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 610 PM CDT THU JUL 11 2013
THE MAIN CHALLENGES WILL BE CONVECTIVE CHANCES LATER TONIGHT AND
FRIDAY. EXPECT AN MCS TO AFFECT AT LEAST NORTHERN AREAS LATER
TONIGHT...AND WILL INTRODUCE SOME THUNDER IN THE NORTH. THERE
COULD BE MORE SHOWERS AND STORMS FRIDAY AFTERNOON...BUT WITH
STRONG CAPPING INVERSION IN PLACE WON/T MENTION YET...BUT THREAT
IS THERE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...DK
SHORT TERM...SPEICHER
LONG TERM...SPEICHER/VOELKER
AVIATION...DK
AREA FORECAST DISCUSSION
NWS PORTLAND OR
834 AM PDT WED JUL 10 2013
.SYNOPSIS...A SERIES OF WEAK UPPER TROUGHS WILL REINTRODUCE ONSHORE
FLOW AND DRY AND MILD WEATHER OVER SOUTHWEST WASHINGTON AND NORTHWEST
OREGON THROUGH THE REMAINDER OF THE WEEK. THESE SYSTEMS WILL DEEPEN
THE MARINE LAYER AND DROP INLAND TEMPS TO NEAR OR A BIT BELOW
NORMAL....WITH VARYING DEGREES OF INLAND MORNING CLOUDS. ANY CHANCE
OF THUNDERSTORMS WILL BE SOUTH AND EAST OF OUR FORECAST AREA. WE MAY
GET SOME WARMING AGAIN EARLY NEXT WEEK.
&&
.SHORT TERM....CLOUDS MADE IT INTO THE COAST RANGE GAPS BUT THE
MARINE LAYER IS SHALLOW... THUS MOST LOW CLOUDINESS INLAND IS
CONFINED TO THE COLUMBIA RIVER GAP WITH SOME POCKETS AROUND THE S WA
FOOTHILLS AND NEAR THE GORGE. FAVOR THE TEMPS CLOSER TO WARMER
EC/MAV GUIDANCE WITH LESS CLOUD COVER OBSERVED...AND THIS COVERED
REASONABLY WELL IN CURRENT FCST.
HI RESOLUTION GUIDANCE FROM THE HRRR AND 4 KM WRF SUGGEST
THUNDERSTORMS TODAY WILL REMAIN EAST OF THE CASCADE CREST. SPC HAS A
GENERAL THUNDER JUST SOUTH AND EAST OF THE LANE COUNTY CASCADES. WE
MAY STILL SEE SOME CUMULUS BUILDUPS OR PASSING HIGH CLOUDS ALONG THE
LANE COUNTY CASCADES...POSSIBLY A BIT FURTHER NORTH...IN RESPONSE TO
THE INLAND PROPAGATING DISTURBANCE CURRENTLY OFF THE NORTHERN
CALIFORNIA COAST. SW FLOW AHEAD OF THIS DAMPENING WAVE IS CONSISTENT
WITH THIS SIGNAL IN PUSHING CONVECTION EAST.
MODELS SUGGEST A STRONGER MARINE PUSH TONIGHT INTO THURSDAY MORNING.
EXPECT LOW CLOUDS TO PUSH INTO THE CASCADE FOOTHILLS THROUGH THURSDAY
MORNING...WITH MORE COVERAGE FOR THE VALLEY. EXPECT THE MOST COVERAGE
FOR THE NORTH COAST RANGE AND INTO THE NORTH VALLEY AS THE UPPER
WAVES OFFSHORE CONSOLIDATE. WE WILL FEEL THE IMPACTS OF THE NORTHERN
WAVE THE MOST...AND SINCE IT PASSES BY THROUGH WASHINGTON...THE
MARINE LAYER WILL BE DEEPEST NORTH. WITH THIS DEEPER LAYER AND THE
WAVE MOVING THROUGH...SOME PATCHY DRIZZLE IS EXPECTED ALONG THE NORTH
COAST/COAST RANGE.
WE REMAIN UNDER THE INFLUENCE OF BROAD TROUGHINESS....WITH VARYING
DEGREES OF MORNING CLOUDS AND AFTERNOON SUN FRIDAY AND SATURDAY. KMD
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...FRIDAY EVENING
THROUGH MONDAY...THE MEDIUM RANGE MODELS SHOW A SHORTWAVE TROUGH
COMING THROUGH THE FCST LATE FRI OR EARLY SAT. THE TROUGH IS SHARP
ENOUGH THAT A SLIGHT CHC OF SPRINKLES OR DRIZZLES WAS ADDED TO THE
FCST FOR THE COAST AND COAST RANGE OVERNIGHT FRI INTO SAT MORNING.
SAT LOOKS TO BE A TRANSITION DAY...WITH PLENTY OF CLOUDS BUT TEMPS
WARMING BACK TO NEAR SEASONAL AVGS. THEN A LARGE UPPER LEVEL RIDGE
OVER THE CENTRAL U.S. WILL BUILD TOWARDS THE PAC NW BRINGING MORE SUN
AND ABOVE AVERAGE TEMPS FOR SUN INTO EARLY NEXT WEEK. THE LATEST
MODEL TRENDS INDICATE THAT THE STRENGTH OF THE RIDGE WILL NOT BE
QUITE AS STRONG AS PREVIOUS RUNS WERE INDICATING. HOWEVER...ON THE
WARMEST DAYS OF SUN AND MON INTERIOR LOWLAND SITES MAY STILL APPROACH
90 DEG. PYLE
&&
.AVIATION...NORTHERLY SURFACE WINDS WILL KEEP THE MUCH OF THE
OREGON COAST UNDER LOWER CIGS TODAY. EXPECT THE S WA AND N OREGON
COAST WILL BE LOW-END MVFR THROUGH AT LEAST 19Z. AREAS S OF KTMK
EXPECTED TO CLEAR AFTER 19Z...BUT NOT AS CONFIDENT N OF KTMK.
OTHERWISE...CLEAR SKIES INLAND TODAY. MARINE LAYER PUSHES INLAND
TONIGHT.
KPDX AND APPROACHES...VFR UNDER CLEAR SKIES TODAY.
MARINE LAYER RETURNS TONIGHT...FOR MVFR CONDITIONS FROM AROUND 12Z
THROUGH 18Z THU.
&&
.MARINE...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS. SIMILAR
PATTERN FOR THE NEXT FEW DAYS. BASED ON CONDITIONS TUE DECIDED TO
GO WITH A SMALL CRAFT ADVISORY FOR WIND IN THE N WATERS FROM 18Z
TODAY THROUGH 09Z THU. GRADIENT EASES A BIT THU. SRN WATERS WILL
CONTINUE WITH THE PERSISTENT 25 KT GUSTS FROM LATE-MORNING THROUGH
LATE-EVENING.
CONTINUAL SHORT-PERIOD AND MOSTLY WIND-DRIVEN SEAS FOR THE NEXT
FEW DAYS. OVERALL WAVE HEIGHTS AND STEEPNESS PARAMETERS TO REMAIN
BELOW ADVISORY THRESHOLDS. WEISHAAR
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 2 AM PDT THURSDAY FOR
COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR OUT 60
NM.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 5 AM PDT THURSDAY FOR
COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT 60 NM.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWS.PORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
811 PM EDT THU JUL 11 2013
.SYNOPSIS...
A COLD FRONT WILL SLOWLY CROSS THE REGION TONIGHT. SOMEWHAT DRIER
CONDITIONS SHOULD SPREAD INTO THE REGION IN THE WAKE OF THE FRONT
FRIDAY. HOWEVER...DEEPER MOISTURE WILL RETURN TO THE WESTERN
CAROLINAS AND NORTHEAST GEORGIA THIS WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 745 PM EDT...CONVECTIVE COVERAGE IS STARTING TO INCREASE
RAPIDLY ONCE AGAIN THIS EVENING OVER PIEDMONT SECTIONS...WHERE AN
UPPER VORT LOBE IS PASSING OVERHEAD...250 MB WIND DIVERGENCE REMAINS
FAIRLY STRONG...AND LOW LEVEL CONVERGENCE HAS INCREASED AHEAD OF THE
APPROACHING COLD FRONT. WILL CONTINUE TO FEATURE LIKELY TO
CATEGORICAL POPS IN THE PIEDMONT THROUGH AT LEAST 11 PM WITH THESE
FEATURES. IN ADDITION...THE LATEST HRRR MODEL RUN HAS OTHER
CONVECTION FORMING ALONG THE SC/NC MTNS AND SLIPPING SE THROUGH THE
EARLY OVERNIGHT HOURS. POPS WILL BE INCREASED INTO THE MORE SOLID
CHC RANGE FOR THIS ACTIVITY EVEN THOUGH IT HAS NOT DEVELOPED YET
SINCE THE HRRR HAS BEEN FAIRLY ACCURATE WITH THE PIEDMONT
DEVELOPMENT. THE FLASH FLOOD WATCH REMAINS WELL PLACED TO CAPTURE
ALL OF THIS HEAVY RAINFALL POTENTIAL. THE STRONGEST CORES MAY ALSO
PRODUCE SOME GUSTY WINDS...BUT PROFILES APPEAR A BIT TOO WARM AND
MOIST FOR MUCH LARGE HAIL THREAT...AND DCAPE VALUES REMAIN FAIRLY
LOW OVER THE PIEDMONT WHERE CORES SHOULD BE TALLEST.
THE UPPER SUPPORT AND WEAK SFC COLD FRONT PRODUCING THE EVENING
CONVECTION WILL SLOWLY MOVE EAST OF THE AREA OVERNIGHT. THIS
COMBINED WITH THE LOSS OF HEATING SHOULD LEAD TO A GRADUAL
DIMINISHING TREND TO CONVECTION DURING THE OVERNIGHT HOURS. IF THESE
TRENDS DEVELOP AS EXPECTED...THE FLOOD THREAT SHOULD DIMINISH
OVERNIGHT AS WELL. EXPECT ANOTHER NIGHT OF DEVELOPING LOW CLOUDS AND
AREAS OF FOG...WITH PATCHY DENSE FOG POSSIBLE...AS LOW LEVEL
MOISTURE REMAINS QUITE HIGH AND FLOW BECOMES LIGHT OR TAKES ON A
WEAK EASTERLY COMPONENT AS WEAK HIGH PRESSURE NOSES IN FROM THE NW.
LOWS WILL BE WARM...BUT A LITTLE COOLER THAN LAST NIGHT.
AN UPPER LOW WILL WRAP UP AND DROP SOUTH TOWARD THE AREA FRI. SOME
WEAK SHORT WAVE ENERGY MOVES NORTH OVER THE CWFA AHEAD OF THIS
SYSTEM. THE BEST UPPER DIVERGENCE REMAINS TO OUR EAST ALONG WITH
DEEP MOISTURE. HOWEVER...COPIOUS LOW LEVEL MOISTURE COMBINED WITH
THE EASTERLY COMPONENT TO THE WIND WILL KEEP THE CHC OF AFTERNOON
CONVECTION ACROSS THE AREA. WHILE PW VALUES SHUD BE MUCH LESS THAN
PREVIOUS DAYS GIVEN THE LACK OF DEEP MOISTURE...WILL STILL HAVE TO
WATCH FOR ISOLATED FLOODING GIVEN THE ANTECEDENT CONDITIONS. HIGHS
SHOULD REBOUND 5 OR MORE DEGREES ACROSS THE WEST AND AROUND 3
DEGREES OVER THE EAST.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
AS OF MIDDAY THU...STALLED FRONTAL BDY NEAR THE SE ATLANTIC COAST
WILL BEGIN TO PUSH WEST AS A WARM FRONT FRIDAY NIGHT AS BERMUDA HIGH
BUILDS. CLOSED UPPER LOW SIMULTANEOUSLY WILL BEGIN TO RETROGRADE INTO
THE OHIO VALLEY. DESPITE BETTER MOISTURE MOSTLY REMAINING TO OUR
EAST...WEAK SOUTHEASTERLY MIDLEVEL FLOW OVERNIGHT WILL PROVIDE LIFT
TO KEEP DIURNAL CONVECTION GOING INTO THE EVENING. THE UPPER LOW
SLIDES ACROSS THE MTNS AS WELL...PROVIDING ADDITIONAL FORCING THAT
MAY TRIGGER SOME SHOWERS. PROG SOUNDINGS IN THE MTNS ARE LARGELY DRY
ALOFT BUT UNSTABLE ENOUGH TO EXPECT THE LOW MIGHT KICK OFF A FEW
CELLS. THUS HAVE MAINTAINED HIGHEST POPS EAST NEARER THE FRONTAL
MOISTURE. CELL MOTION WILL REMAIN FAIRLY SLOW WITH WEAK WINDS THRU
THE COLUMN. PWAT VALUES ARE WELL BELOW NORMAL IN OUR WEST BUT NEAR
NORMAL EAST...SO FLASH FLOODING FROM ANY TSTMS THAT ARE ABLE TO
CONTINUE/DEVELOP OVERNIGHT WILL BE A CONCERN THERE...INCLUDING THE
CHARLOTTE METRO.
ON SATURDAY THE BOUNDARY CONTINUES TO MOVE WEST BRINGING TROPICAL
MOISTURE AND CLIMATOLOGICALLY HIGH PWATS BACK ACROSS THE WHOLE
CWFA...BUT CONTINUING TO BE MOST IMPRESSIVE EAST. SELY FLOW BECOMES
MORE UNIDIRECTIONAL ALOFT AS THE UPPER LOW CENTER MOVES INTO KY/TN.
DEEP MOISTURE PEAKS AND SOUNDINGS BECOME NEARLY SATURATED BY LATE SAT
AFTN...WITH LIMITED INSTABILITY BUT STILL WITH SLOW STORM MOTION
VECTORS. SAT NIGHT THE GFS FEATURES THE WEAK REMNANT LOW FROM CHANTAL
MAKING ITS WAY THRU THE CAROLINAS...WITH THE MAIN EFFECT TO BE TO
CREATE SOMEWHAT OF A LLVL JET OVER THE NRN NC PIEDMONT AND FOOTHILLS.
NAM DOES NOT SHOW THIS FEATURE...BUT NONETHELESS THE SE FLOW WILL
CONTINUE TO SUPPORT AT LEAST SOME PRECIP OVERNIGHT.
SOUNDINGS ARE SOMEWHAT DRIER AND MORE UNSTABLE ON SUNDAY AS TROPICAL
MOISTURE...ALSO LIKELY A REMNANT OF CHANTAL...REMAINS OVER THE AREA.
HAVE INCLUDED A MORE PRONOUNCED DIURNAL PEAK ON SUNDAY GIVEN THE
INSTABILITY. OTHERWISE THE STORY IS PRETTY SIMILAR WITH SE FLOW
ALBEIT WEAKER WITH THE HIGH BECOMING CENTERED CLOSER TO THE MID
ATLANTIC COAST AND THE UPPER LOW OUT OF THE PICTURE. FLASH FLOOD
THREAT MAY BECOME MORE LOCALIZED SUNDAY WITH CONVECTIVE ACTIVITY
BEING THE MAIN PRECIP PRODUCER...BUT THE THREAT MAY BE GREATER GIVEN
THE EVEN SLOWER STORM MOTION.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 11 AM THURSDAY...HIGH PRESSURE OVER THE MID ATLANTIC COAST WILL
EXPAND WESTWARD EARLY NEXT WEEK...FORCING THE CUTOFF UPPER LOW OUT OF
THE OHIO VALLEY AND TOWARD THE GREAT PLAINS. ABUNDANT MOISTURE LOOKS
TO ACCOMPANY THE BOUNDARY AT THE INTERFACE OF THESE TWO FEATURES...
THOUGH BAROCLINIC FORCING IS MINIMAL. LONG TERM GUIDANCE PLACES THE
PLUME OF BETTER MOISTURE ANYWHERE FROM THE SRN APPALACHIANS TO THE
MID TENNESSEE VALLEY. 11/06Z GFS KEEPS THE ASSOCIATED PRECIP IN OUR
MTN ZONES EARLY MON...WHILE OTHER MODELS FAVOR TO VARYING DEGREES A
MORE WESTWARD POSITION TO THE UPPER LOW AND THUS A WEAKER HEIGHT
GRADIENT WITH A LESS FOCUSED AREA OF ENHANCED PRECIP. REGARDLESS OF
WHETHER THE BOUNDARY PLAYS A ROLE EARLY IN THE FORECAST
PERIOD...SOUTHEASTERLY TO EASTERLY FLOW WILL PERSIST THRU THE PERIOD
WITH THE COASTAL HIGH TO OUR NORTH PROVIDING AT LEAST WEAK UPSLOPE
FLOW TO ENHANCE THE EFFECTS OF DIURNAL CONVECTION SOUTH AND EAST OF
THE SPINE OF THE APPALACHIANS. TEMPERATURES WILL REMAIN JUST BELOW
NORMAL BUT GRADUALLY MODERATE AS THE HIGH DRIFTS SOUTH FORMING A MORE
CLASSICAL BERMUDA HIGH PATTERN BY LATE WEEK.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
AT KCLT...LATE EVENING CONVECTION HAS BEEN DEVELOPING WELL SOUTH AND
WELL NORTH OF THE AIRFIELD...BUT COULD CONVERGE ON THE AIRPORT
THROUGH THE LATE EVENING HOURS. GIVEN THE TREND OF EARLIER ACTIVITY
TO BACKBUILD MAINLY TOWARD THE SW...WILL NOT INCLUDE ANY TSTM
MENTION AT KCLT AT PRESENT...BUT THIS WILL NEED CLOSE WATCHING.
OTHERWISE...EXPECT MAINLY JUST SHOWERS IN THE VICINITY...WITH MVFR
THEN IFR STRATUS FORMING OVERNIGHT AS THE PRECIPITATION DISSIPATES
BUT ABUNDANT BL MOISTURE REMAINS. LIGHT SW WINDS EARLY WILL BECOME
NE DURING THE MORNING HOURS FRI. EXPECT VERY SLOW IMPROVEMENT OF
CIGS THROUGH MVFR FRI MORNING...WITH MAINLY VFR CIGS AND LOW END
THUNDER CHANCES IN THE ENE FLOW THROUGH FRI AFTN.
ELSEWHERE...SHRA COVERAGE REMAINS VERY LIMITED ACROSS THE MTNS AND
FOOTHILLS THIS EVENING...WITH THE BETTER UPPER FORCING AND
INSTABILITY ACROSS THE PIEDMONT. SOME BACKBUILDING OF PIEDMONT
CONVECTION IS ONGOING...AND THIS WILL HAVE TO BE MONITORED FOR TSTM
INCLUSION AT THE FOOTHILLS TAFS AS THE FRONTAL ZONE SLIPS IN FROM
THE NW AND CONVERGENCE IMPROVES SLIGHTLY. WILL MAINTAIN ONLY SHOWERS
IN THE VICINITY FOR NOW...WITH LOW STRATUS A GOOD BET IN THE
LINGERING BL MOISTURE OVERNIGHT. WILL FORECAST IFR THROUGHOUT WITH
LIFR LIKELY FROM KAVL TO KHKY. LIGHT WINDS WILL TURN NE THROUGH
FRIDAY AT THE FOOTHILL TAFS WHILE REMAINING LIGHT NW AT KAVL.
ANTICIPATE SCATTERED COVERAGE OF AFTN TSTMS IN WEAK EASTERLY UPSLOPE
FLOW FRI AFTN...ESPECIALLY IN AND NEAR THE MTNS.
OUTLOOK...A COLD FRONT WILL STALL OVER THE PIEDMONT OF THE CAROLINAS
FRIDAY AND THEN SLOWLY DISSIPATE THROUGH THE WEEKEND. LOW LEVEL
MOISTURE WILL PERSIST...CONTINUING THE CHANCES FOR DIURNAL
THUNDERSTORMS AND MORNING FOG/LOW CLOUDS INTO EARLY NEXT WEEK.
CONFIDENCE TABLE...
00-06Z 06-12Z 12-18Z 18-24Z
KCLT HIGH 94% MED 73% HIGH 82% HIGH 100%
KGSP HIGH 93% MED 66% HIGH 85% HIGH 100%
KAVL MED 73% MED 70% MED 66% HIGH 94%
KHKY MED 62% MED 71% MED 72% HIGH 97%
KGMU HIGH 88% MED 67% MED 76% HIGH 100%
KAND HIGH 94% MED 66% MED 70% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FLASH FLOOD WATCH UNTIL 4 AM EDT FRIDAY FOR GAZ010-017-018-026-
028-029.
NC...FLASH FLOOD WATCH UNTIL 4 AM EDT FRIDAY FOR NCZ033-035>037-049-
050-053-056-057-063>065-068>072-082-501>510.
SC...FLASH FLOOD WATCH UNTIL 4 AM EDT FRIDAY FOR SCZ001>014-019.
&&
$$
SYNOPSIS...RWH
NEAR TERM...HG
SHORT TERM...WIMBERLEY
LONG TERM...WIMBERLEY
AVIATION...HG
SEE BELOW FOR AN UPDATED AVIATION FORECAST DISCUSSION.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT
MAIN CHALLENGE THROUGH THE SHORT TERM IS THUNDERSTORM INTENSITY
AND PLACEMENT.
A COLD FRONT BEGINS TO SWING THROUGH THE DAKOTAS THIS EVENING.
WITH H7 TEMPS +14 TO +16 IT APPEARS THAT MOST AREAS WILL BE TOO
CAPPED TO MAKE USE OF THE ABUNDANT SHEAR. AN H7 SHORTWAVE DOES
CLIP NORTH CENTRAL SD AFTER 3Z...AFFECTING
CORSON/DEWEY/CAMPBELL/WALWORTH AFTER MIDNIGHT. THIS WAVE MAY
PROVIDE ENOUGH FORCING TO KICK OFF A FEW STORMS. THE SHORTWAVE
THEN CATCHES UP WITH THE FRONT LATE FRIDAY MORNING...POSSIBLY. IF
TIMING IS ACCURATE COULD SEE SOME STORMS POP ON A BROWN COUNTY TO
LYMAN COUNTY LINE AND PROGRESS EASTWARD INTO AN ENVIRONMENT WITH
1500 J/KG OF CAPE AND ALMOST 50 KTS OF SHEAR. SEVERE STORMS WOULD
BE PROBABLE IF ANYTHING DEVELOPS...ESPECIALLY BY LATE AFTERNOON
AND EARLY EVENING.
ANOTHER LOW WITH A WARM AIR BOUNDARY SETS UP ON SATURDAY. A
SHORTWAVE ALSO MOVES THROUGH SAT EVENING STRETCHING FROM WEST
CENTRAL MN SOUTHWEST TOWARD LYMAN COUNTY. WITH ONLY VERY LIMITED
CAPPING THIS AREA ACROSS EASTERN SD AND WEST CENTRAL MN LOOKS MOST
LIKELY FOR SEVERE THUNDERSTORM DEVELOPMENT THROUGH THE EVENING AND
OVERNIGHT.
.LONG TERM...SUNDAY THROUGH THURSDAY
SUNDAY AND SUNDAY NIGHT LOOKS TO REMAIN FAIRLY ACTIVE AS WARM
FRONT IS STILL DRAPED FROM WEST TO EAST ACROSS THE REGION WITH
GOOD CHANCES FOR SHOWERS AND THUNDERSTORMS. PLENTY OF MOISTURE AND
INSTABILITY AROUND AS WELL SO COULD BE LOOKING AT SEVERE STORMS
ALSO. MODELS AGREE FAIRLY WELL IN PUSHING THE WARM FRONT NORTH OF
THE REGION BY MONDAY AFTERNOON. THUS...PRECIPITATION CHANCES
DECREASE ON MONDAY AND ESPECIALLY BY MONDAY NIGHT. AFTER
THIS...MODELS SHOWING A FAIRLY DRY PATTERN SHAPING UP AT LEAST
INTO THE MIDDLE/END OF THE WEEK.
&&
.AVIATION...
00Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
AT THIS POINT...IT STILL LOOKS AS THOUGH 99 PERCENT OF CONVECTION
COVERAGE TONIGHT INTO FRIDAY WILL BE OVER NORTH DAKOTA OR FAR
WESTERN SOUTH DAKOTA...LEAVING VFR CONDITIONS TO PREVAIL ACROSS
THIS FORECAST AREA THROUGH THE TAF FORECAST PERIOD. THAT SAID THE
LAST THREE HOURS OF HRRR SOLUTIONS HAS TAKEN TO PROGGING
CONVECTIVE DEVELOPMENT INTO PRIMARILY THE NORTHERN HALF OF
FORECAST ZONES OVERNIGHT...STARTING OUT WEST AT OR AFTER 02Z AND
TRUDGING CONVECTION OVER INTO FAR NORTHEAST SOUTH DAKOTA BY 09Z
FRIDAY MORNING. FOR NOW...WILL CONTINUE MONITORING FOR ANY
POTENTIAL CONVECTIVE DEVELOPMENT OVER WESTERN SOUTH DAKOTA AND GO
FROM THERE. ALSO...GUSTY SOUTHERLY SFC WINDS WILL ALSO AFFECT THE
TAF SITES...MORE SO KABR AND KATY. A FRONTAL BOUNDARY WILL MOVE
THROUGH THE AREA ON FRIDAY AND BEGIN TO SWITCH SFC WINDS TO A
NORTH OR NORTHWEST DIRECTION AT KPIR AND KMBG BY MID DAY FRIDAY.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...DORN
SHORT TERM...WISE
LONG TERM...TMT
AVIATION...DORN
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1000 PM CDT THU JUL 11 2013
.UPDATE...
MOST SHOWERS AND THUNDERSTORMS OVER EASTERN AND CENTRAL TEXAS HAVE
COME TO AN END THIS EVENING WITH ONLY SOME LINGERING SHOWERS TO
THE NORTH OF THE HILL COUNTRY. THE ONLY THING LEFT FROM THESE
EARLIER STORMS IS AN OUTFLOW BOUNDARY ENTERING THE NORTHEAST PART
OF WILLIAMSON COUNTY. THIS BOUNDARY WILL BRING A SLIGHTLY WIND
SHIFT ACROSS PARTS OF THE NORTHEAST HILL COUNTRY FOR A SHORT
PERIOD OF TIME WITH WIND GUSTS UP TO 20 MPH. CURRENT FORECAST IS ON
TRACK FOR THE REST OF THIS EVENING INTO FRIDAY MORNING.
&&
.PREV DISCUSSION... /ISSUED 707 PM CDT THU JUL 11 2013/
UPDATE...
INCREASED CLOUD COVERAGE THIS EVENING INTO THE OVERNIGHT HOURS AS
MID TO UPPER MOISTURE ASSOCIATED WITH A GROUP OF STORMS OVER EAST
TEXAS MOVE TO THE SOUTHWEST. HI-RES MODELS AND LATEST RAP SOLUTION
SHOWS STORMS SCATTERING OUT BEFORE ARRIVING TO THE NORTHEAST PART OF
THE HILL COUNTRY. WILL MONITOR CLOSELY THESE STORMS AS THEY
APPROACH THE LOCAL AREA FOR THE NEXT FEW HOURS AND ADJUST WEATHER
GRIDS IF NECESSARY. UPDATED ZONES OUT SHORTLY.
PREV DISCUSSION... /ISSUED 623 PM CDT THU JUL 11 2013/
AVIATION...
VFR CONDITIONS PREVAILING FOR THE NEXT 24 HOURS AS UPPER LEVEL
HIGH PRESSURE CENTERED OVER THE SRN ROCKIES KEEPS S TX UNDER
GENERAL SUBSIDENCE. WEAK DISTURBANCES ROTATING AROUND THE UPPER
RIDGE WILL MAINLY AFFECT THE N TX AREA WITH ISOLD-SCT AFTERNOON
AND EVENING SHRA/TSRA THAT SHOULD REMAIN NORTH OF THE S CENTRAL
TX. OTHERWISE S-SELY SFC WINDS AT 5-10 KNOTS PREVAILING.
PREV DISCUSSION... /ISSUED 331 PM CDT THU JUL 11 2013/
SHORT TERM (TONIGHT THROUGH FRIDAY NIGHT)...
THE SUBTROPICAL RIDGE AXIS REMAINS THE DOMINANT WEATHER FEATURE
THROUGH THE SHORT TERM PORTION OF THE FORECAST. GIVEN THE INFLUENCE
FROM THIS RIDGE...WE EXPECT A CONTINUATION OF DRY WEATHER ACROSS
SOUTH CENTRAL TEXAS. THE SHORT RANGE MODELS DO SHOW SOME CONVECTION
CONTINUING ACROSS NORTH TEXAS THIS EVENING...WITH SOME ACTIVITY
DRIFTING INTO CENTRAL TEXAS LATE TONIGHT INTO EARLY FRIDAY
MORNING. WE HAVE LOW CONFIDENCE THIS CONVECTION WILL BE ABLE TO
MOVE INTO OUR REGION...SO WE WILL CONTINUE WITH A DRY FORECAST.
HIGH TEMPERATURES REMAIN ABOVE NORMAL ON FRIDAY AND WILL RANGE
FROM THE MID/UPPER 90S IN THE HILL COUNTRY...WITH UPPER 90S TO
100-103 FOR THE REMAINDER OF THE REGION. OVERNIGHT LOWS WILL
REMAIN IN THE 70S.
LONG TERM (SATURDAY THROUGH THURSDAY)...
A BROAD SUBTROPICAL RIDGE WILL ENCOMPASS MUCH OF THE CENTRAL CONUS
THROUGH THE FIRST HALF OF THE UPCOMING WEEKEND. DRY CONDITIONS AND
ABOVE NORMAL TEMPERATURES WILL CONTINUE FOR ALL AREAS ON SATURDAY.
BASED ON THE LATEST MODEL DATA...IT APPEARS SATURDAY WILL BE THE
WARMEST DAY OF THE FORECAST PERIOD...WITH HIGHS GENERALLY IN THE
UPPER 90S TO NEAR 104. MODEL DATA FROM THE LAST SEVERAL DAYS WERE
CONSISTENT IN SHOWING A TUTT LOW MOVE ACROSS THE REGION LATE THIS
WEEKEND INTO EARLY NEXT WEEK. THE LATEST GUIDANCE DOES CONTINUE TO
SHOW A WEAK TUTT LOW...BUT ALSO SHOW A LOW DEVELOPING OVER THE UPPER
MIDWEST BY LATE FRIDAY. THE MODELS THEN RETROGRADE THIS LOW
SOUTHWEST INTO THE SOUTHERN U.S. PLAINS BY EARLY NEXT WEEK.
OVERALL... WE ARE NOT TOO CONFIDENT IN RAIN CHANCES INTO EARLY NEXT
WEEK. FOR NOW... WE WILL MAINTAIN THE CURRENT FORECAST WHICH
GENERALLY CALLS FOR A SLIGHT CHANCE (20%) OF RAIN FOR MOST AREAS
SUNDAY NIGHT THROUGH TUESDAY NIGHT. THROUGH THE REMAINDER OF THE
FORECAST PERIOD...WE WILL GO WITH A DRY FORECAST...EXCEPT NEAR THE
COASTAL PLAINS WHERE AFTERNOON/EVENING SEA BREEZE CONVECTION REMAINS
POSSIBLE. AS MENTIONED ABOVE...TEMPERATURES WILL PEAK ON SATURDAY...
THEN VERY SLOWLY MODERATE SUNDAY THROUGH THURSDAY. IT APPEARS A
BREAK FROM TRIPLE DIGIT HIGHS IS IN STORE...BUT TEMPERATURES WILL
CONTINUE TO REMAIN ABOVE NORMAL.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 75 103 75 104 76 / - - - - -
AUSTIN BERGSTROM INTL AIRPORT 72 101 72 102 72 / - - - - -
NEW BRAUNFELS MUNI AIRPORT 71 100 72 101 72 / - - - - -
BURNET MUNI AIRPORT 74 101 76 101 74 / 10 - - - -
DEL RIO INTL AIRPORT 77 101 77 103 77 / - - - - -
GEORGETOWN MUNI AIRPORT 74 101 74 101 74 / 10 - - - -
HONDO MUNI AIRPORT 74 101 74 102 73 / - - - - -
SAN MARCOS MUNI AIRPORT 72 100 72 101 72 / - - - - -
LA GRANGE - FAYETTE REGIONAL 76 102 76 101 77 / - 10 10 10 10
SAN ANTONIO INTL AIRPORT 77 101 77 101 77 / - - - - -
STINSON MUNI AIRPORT 75 101 75 101 75 / - - - - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...01
SYNOPTIC/GRIDS...17
PUBLIC SERVICE/DATA COLLECTION...12
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
707 PM CDT THU JUL 11 2013
.UPDATE...
INCREASED CLOUD COVERAGE THIS EVENING INTO THE OVERNIGHT HOURS AS
MID TO UPPER MOISTURE ASSOCIATED WITH A GROUP OF STORMS OVER EAST
TEXAS MOVE TO THE SOUTHWEST. HI-RES MODELS AND LATEST RAP SOLUTION
SHOWS STORMS SCATTERING OUT BEFORE ARRIVING TO THE NORTHEAST PART OF
THE HILL COUNTRY. WILL MONITOR CLOSELY THESE STORMS AS THEY
APPROACH THE LOCAL AREA FOR THE NEXT FEW HOURS AND ADJUST WEATHER
GRIDS IF NECESSARY. UPDATED ZONES OUT SHORTLY.
&&
.PREV DISCUSSION... /ISSUED 623 PM CDT THU JUL 11 2013/
AVIATION...
VFR CONDITIONS PREVAILING FOR THE NEXT 24 HOURS AS UPPER LEVEL
HIGH PRESSURE CENTERED OVER THE SRN ROCKIES KEEPS S TX UNDER
GENERAL SUBSIDENCE. WEAK DISTURBANCES ROTATING AROUND THE UPPER
RIDGE WILL MAINLY AFFECT THE N TX AREA WITH ISOLD-SCT AFTERNOON
AND EVENING SHRA/TSRA THAT SHOULD REMAIN NORTH OF THE S CENTRAL
TX. OTHERWISE S-SELY SFC WINDS AT 5-10 KNOTS PREVAILING.
PREV DISCUSSION... /ISSUED 331 PM CDT THU JUL 11 2013/
SHORT TERM (TONIGHT THROUGH FRIDAY NIGHT)...
THE SUBTROPICAL RIDGE AXIS REMAINS THE DOMINANT WEATHER FEATURE
THROUGH THE SHORT TERM PORTION OF THE FORECAST. GIVEN THE INFLUENCE
FROM THIS RIDGE...WE EXPECT A CONTINUATION OF DRY WEATHER ACROSS
SOUTH CENTRAL TEXAS. THE SHORT RANGE MODELS DO SHOW SOME CONVECTION
CONTINUING ACROSS NORTH TEXAS THIS EVENING...WITH SOME ACTIVITY
DRIFTING INTO CENTRAL TEXAS LATE TONIGHT INTO EARLY FRIDAY
MORNING. WE HAVE LOW CONFIDENCE THIS CONVECTION WILL BE ABLE TO
MOVE INTO OUR REGION...SO WE WILL CONTINUE WITH A DRY FORECAST.
HIGH TEMPERATURES REMAIN ABOVE NORMAL ON FRIDAY AND WILL RANGE
FROM THE MID/UPPER 90S IN THE HILL COUNTRY...WITH UPPER 90S TO
100-103 FOR THE REMAINDER OF THE REGION. OVERNIGHT LOWS WILL
REMAIN IN THE 70S.
LONG TERM (SATURDAY THROUGH THURSDAY)...
A BROAD SUBTROPICAL RIDGE WILL ENCOMPASS MUCH OF THE CENTRAL CONUS
THROUGH THE FIRST HALF OF THE UPCOMING WEEKEND. DRY CONDITIONS AND
ABOVE NORMAL TEMPERATURES WILL CONTINUE FOR ALL AREAS ON SATURDAY.
BASED ON THE LATEST MODEL DATA...IT APPEARS SATURDAY WILL BE THE
WARMEST DAY OF THE FORECAST PERIOD...WITH HIGHS GENERALLY IN THE
UPPER 90S TO NEAR 104. MODEL DATA FROM THE LAST SEVERAL DAYS WERE
CONSISTENT IN SHOWING A TUTT LOW MOVE ACROSS THE REGION LATE THIS
WEEKEND INTO EARLY NEXT WEEK. THE LATEST GUIDANCE DOES CONTINUE TO
SHOW A WEAK TUTT LOW...BUT ALSO SHOW A LOW DEVELOPING OVER THE UPPER
MIDWEST BY LATE FRIDAY. THE MODELS THEN RETROGRADE THIS LOW
SOUTHWEST INTO THE SOUTHERN U.S. PLAINS BY EARLY NEXT WEEK.
OVERALL... WE ARE NOT TOO CONFIDENT IN RAIN CHANCES INTO EARLY NEXT
WEEK. FOR NOW... WE WILL MAINTAIN THE CURRENT FORECAST WHICH
GENERALLY CALLS FOR A SLIGHT CHANCE (20%) OF RAIN FOR MOST AREAS
SUNDAY NIGHT THROUGH TUESDAY NIGHT. THROUGH THE REMAINDER OF THE
FORECAST PERIOD...WE WILL GO WITH A DRY FORECAST...EXCEPT NEAR THE
COASTAL PLAINS WHERE AFTERNOON/EVENING SEA BREEZE CONVECTION REMAINS
POSSIBLE. AS MENTIONED ABOVE...TEMPERATURES WILL PEAK ON SATURDAY...
THEN VERY SLOWLY MODERATE SUNDAY THROUGH THURSDAY. IT APPEARS A
BREAK FROM TRIPLE DIGIT HIGHS IS IN STORE...BUT TEMPERATURES WILL
CONTINUE TO REMAIN ABOVE NORMAL.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 75 103 75 104 76 / - - - - -
AUSTIN BERGSTROM INTL AIRPORT 72 101 72 102 72 / - - - - -
NEW BRAUNFELS MUNI AIRPORT 71 100 72 101 72 / - - - - -
BURNET MUNI AIRPORT 74 101 76 101 74 / 10 - - - -
DEL RIO INTL AIRPORT 77 101 77 103 77 / - - - - -
GEORGETOWN MUNI AIRPORT 74 101 74 101 74 / 10 - - - -
HONDO MUNI AIRPORT 74 101 74 102 73 / - - - - -
SAN MARCOS MUNI AIRPORT 72 100 72 101 72 / - - - - -
LA GRANGE - FAYETTE REGIONAL 76 102 76 101 77 / - 10 10 10 10
SAN ANTONIO INTL AIRPORT 77 101 77 101 77 / - - - - -
STINSON MUNI AIRPORT 75 101 75 101 75 / - - - - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...01
SYNOPTIC/GRIDS...17
PUBLIC SERVICE/DATA COLLECTION...12
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1115 AM CDT WED JUL 10 2013
.UPDATE...
THIS MORNING/S MODELS CONTINUE TO STRUGGLE WITH A SOUTHWARD
MOVING IMPULSE GENERATED BY LAST NIGHTS CONVECTION ACROSS PARTS OF
KANSAS AND MISSOURI. MID LEVEL CLOUDS HAVE INCREASED JUST SOUTH OF
THE RED RIVER THIS MORNING WHICH SHOWS THERE IS SOME MID LEVEL
LIFT THAT MIGHT BECOME SLIGHTLY ENHANCED AS THE IMPULSE NEARS
LATE THIS AFTERNOON/EVENING. DUE TO THIS REASONING...HAVE
MAINTAINED 20-30 POPS FOR AREAS NORTH OF A DECATUR TO CANTON LINE
THIS AFTERNOON THROUGH EVENING.
ALSO DECIDED TO MAKE SOME ADDITIONAL LOCAL BIAS ADJUSTMENTS TO MAX
TEMPS THIS AFTERNOON AND ON THURSDAY.
WE ARE STILL EVALUATING THE RAIN POTENTIAL ASSOCIATED WITH THE
NEXT TWO UPPER LEVEL SYSTEMS. THE FIRST DOES NOT LOOK THAT
IMPRESSIVE DUE TO A LACK OF A GOOD TROPICAL FEED...BUT THE SECOND
ONE NEXT WEEK MOVES FARTHER NORTH ACROSS THE STATE AND SEEMS TO
HAVE A BETTER TROPICAL CONNECTION. 75
&&
.AVIATION...
FOR THE 12Z TAFS...VFR CONDITIONS ARE EXPECTED THROUGH THE VALID
FORECAST PERIOD. A SMALL CHANCE OF AFTERNOON STORMS NEAR THE DFW
METROPLEX IS THE PRIMARY AVIATION WEATHER CONCERN.
HIGH PRESSURE REMAINS IN PLACE OVER THE REGION WHICH WILL HELP
MAINTAIN VFR CONDITIONS THROUGH THE FORECAST PERIOD. THUNDERSTORM
ACTIVITY THAT OCCURRED OVER THE CENTRAL PLAINS EARLY THIS MORNING
IS EXPECTED TO DISSIPATE WITH THEIR REMNANTS MOVING SOUTH TOWARDS
NORTH TX THIS AFTERNOON.
WITH 100 DEGREE HEAT EXPECTED...THE LATEST RAP FORECAST SOUNDINGS
INDICATE AN UNCAPPED ENVIRONMENT FOR THUNDERSTORMS ALL AROUND THE
DFW METROPLEX THIS AFTERNOON. ANY WEAK LIFT MAY BE SUFFICIENT TO
CAUSE ISOLATED STORMS TO DEVELOP NEAR DFW AREA AIRPORTS DURING THE
PEAK HEATING HRS OF THE DAY. CONFIDENCE IN THE REMNANTS OF THE
CENTRAL PLAINS THUNDERSTORM ACTIVITY PROVIDING THIS LIFT REMAINS
LOW...SO DO NOT HAVE A MENTION OF STORMS IN THE TAFS AT THIS TIME.
SEVERAL HIGH RESOLUTION MODELS PRODUCE ISOLATED STORMS NEAR I-20
THIS AFTERNOON SO WILL HAVE TO WATCH SATELLITE IMAGERY CLOSELY
FOR ANY SIGNS THAT A STORM WILL DEVELOP NEAR AREA AIRPORTS.
DOWNBURST WINDS AND CLOUD TO GROUND LIGHTNING ARE THE EXPECTED
IMPACTS FROM ANY THUNDERSTORMS. THUNDERSTORM CHANCES ARE EXPECTED
TO DIMINISH AFTER SUNSET WITH THE LOSS OF DAYTIME HEATING.
CAVANAUGH
&&
.PREV DISCUSSION... /ISSUED 254 AM CDT WED JUL 10 2013/
BASED ON SOME DEEPER MOISTURE AND FORECAST CONVECTION EVIDENT ON
THE RAP/NAM/TTU WRF/4KM WRF/HRRR...WE HAVE ADDED LOW POPS TO THE
NORTH AND NORTHEAST THIS AFTERNOON. THERE IS ALSO SOME WEAK UPPER
SUPPORT IN THE FORM OF A SHORT WAVE MOVING SOUTH DOWN THE BACK
SIDE OF THE UPPER RIDGE THIS AFTERNOON. THIS DISTURBANCE IS
ASSOCIATED WITH THE CURRENT CONVECTION IN KANSAS/MISSOURI.
FOR THURSDAY...AFTERNOON/EVENING CONVECTION IN THE NORTHEAST NEAR
A WEAK BACKDOOR FRONT STILL LOOKS PLAUSIBLE. BY FRIDAY THE RIDGE
STARTS BUILDING BACK OVER NORTH TX SO ANY PRECIP SHOULD BE
CONFINED TO FAR EASTERN COUNTIES. ON SATURDAY SOME OF THE DRIEST
AIR OF THE WEEK MOVES ACROSS THE AREA. BY SATURDAY AFTERNOON DEW
POINTS SHOULD DROP INTO THE 50S ACROSS MUCH OF THE AREA AS THE
SHALLOW GULF MOISTURE MIXES WITH THIS DRY AIR ALOFT. THIS DRY
AIR MASS WILL ALSO ALLOW A LITTLE EXTRA COOLING OVERNIGHT AND
SUNDAY MORNING LOWS WILL BE ALMOST REFRESHING.
IN THE EXTENDED...A TROPICAL LOW WILL MOVE INTO SOUTH TEXAS ON
SUNDAY...AND WE SHOULD SEE SOME ISOLATED CONVECTION...AT LEAST IN
THE SOUTH. COVERAGE IS LIKELY TO BE LOW AS WITH THE PREVIOUS
SYSTEM THAT TOOK A SIMILAR PATH.
GFS/ECMWF BOTH SHOW THAT BY SUNDAY MORNING A 500MB LOW OVER NEW
YORK/NEW ENGLAND STARTS DROPPING SOUTH SOUTHWEST...REACHING
MISSISSIPPI BY WEDNESDAY. THE ECMWF STALLS THIS LOW OVER THE
LOWER MISSISSIPPI VALLEY...BUT THE GFS PUSHES IT WESTWARD ACROSS
NORTH TX THU/FRI. IF THE LOW DOES MOVE INTO THE AREA...IT IS
PROBABLY THE BEST CHANCE FOR MORE WIDESPREAD PRECIPITATION. THIS
FAR OUT...HAVE KEPT THE POPS LOW AND WE WILL WAIT FOR A BETTER
CONSENSUS. 84
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 100 79 100 78 100 / 20 20 20 20 10
WACO, TX 100 78 101 76 101 / 5 5 5 5 10
PARIS, TX 98 76 97 75 95 / 20 20 30 30 20
DENTON, TX 99 78 99 76 99 / 20 20 20 20 10
MCKINNEY, TX 99 78 99 76 98 / 20 20 30 30 10
DALLAS, TX 102 81 101 80 100 / 20 20 20 20 10
TERRELL, TX 100 78 99 76 99 / 20 20 20 20 10
CORSICANA, TX 101 77 100 76 100 / 10 10 10 10 10
TEMPLE, TX 100 75 100 74 101 / 5 5 5 5 5
MINERAL WELLS, TX 101 75 100 73 101 / 10 10 10 10 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/75
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
648 AM CDT WED JUL 10 2013
.AVIATION...
FOR THE 12Z TAFS...VFR CONDITIONS ARE EXPECTED THROUGH THE VALID
FORECAST PERIOD. A SMALL CHANCE OF AFTERNOON STORMS NEAR THE DFW
METROPLEX IS THE PRIMARY AVIATION WEATHER CONCERN.
HIGH PRESSURE REMAINS IN PLACE OVER THE REGION WHICH WILL HELP
MAINTAIN VFR CONDITIONS THROUGH THE FORECAST PERIOD. THUNDERSTORM
ACTIVITY THAT OCCURRED OVER THE CENTRAL PLAINS EARLY THIS MORNING
IS EXPECTED TO DISSIPATE WITH THEIR REMNANTS MOVING SOUTH TOWARDS
NORTH TX THIS AFTERNOON.
WITH 100 DEGREE HEAT EXPECTED...THE LATEST RAP FORECAST SOUNDINGS
INDICATE AN UNCAPPED ENVIRONMENT FOR THUNDERSTORMS ALL AROUND THE
DFW METROPLEX THIS AFTERNOON. ANY WEAK LIFT MAY BE SUFFICIENT TO
CAUSE ISOLATED STORMS TO DEVELOP NEAR DFW AREA AIRPORTS DURING THE
PEAK HEATING HRS OF THE DAY. CONFIDENCE IN THE REMNANTS OF THE
CENTRAL PLAINS THUNDERSTORM ACTIVITY PROVIDING THIS LIFT REMAINS
LOW...SO DO NOT HAVE A MENTION OF STORMS IN THE TAFS AT THIS TIME.
SEVERAL HIGH RESOLUTION MODELS PRODUCE ISOLATED STORMS NEAR I-20
THIS AFTERNOON SO WILL HAVE TO WATCH SATELLITE IMAGERY CLOSELY
FOR ANY SIGNS THAT A STORM WILL DEVELOP NEAR AREA AIRPORTS.
DOWNBURST WINDS AND CLOUD TO GROUND LIGHTNING ARE THE EXPECTED
IMPACTS FROM ANY THUNDERSTORMS. THUNDERSTORM CHANCES ARE EXPECTED
TO DIMINISH AFTER SUNSET WITH THE LOSS OF DAYTIME HEATING.
CAVANAUGH
&&
.PREV DISCUSSION... /ISSUED 254 AM CDT WED JUL 10 2013/
BASED ON SOME DEEPER MOISTURE AND FORECAST CONVECTION EVIDENT ON
THE RAP/NAM/TTU WRF/4KM WRF/HRRR...WE HAVE ADDED LOW POPS TO THE
NORTH AND NORTHEAST THIS AFTERNOON. THERE IS ALSO SOME WEAK UPPER
SUPPORT IN THE FORM OF A SHORT WAVE MOVING SOUTH DOWN THE BACK
SIDE OF THE UPPER RIDGE THIS AFTERNOON. THIS DISTURBANCE IS
ASSOCIATED WITH THE CURRENT CONVECTION IN KANSAS/MISSOURI.
FOR THURSDAY...AFTERNOON/EVENING CONVECTION IN THE NORTHEAST NEAR
A WEAK BACKDOOR FRONT STILL LOOKS PLAUSIBLE. BY FRIDAY THE RIDGE
STARTS BUILDING BACK OVER NORTH TX SO ANY PRECIP SHOULD BE
CONFINED TO FAR EASTERN COUNTIES. ON SATURDAY SOME OF THE DRIEST
AIR OF THE WEEK MOVES ACROSS THE AREA. BY SATURDAY AFTERNOON DEW
POINTS SHOULD DROP INTO THE 50S ACROSS MUCH OF THE AREA AS THE
SHALLOW GULF MOISTURE MIXES WITH THIS DRY AIR ALOFT. THIS DRY
AIR MASS WILL ALSO ALLOW A LITTLE EXTRA COOLING OVERNIGHT AND
SUNDAY MORNING LOWS WILL BE ALMOST REFRESHING.
IN THE EXTENDED...A TROPICAL LOW WILL MOVE INTO SOUTH TEXAS ON
SUNDAY...AND WE SHOULD SEE SOME ISOLATED CONVECTION...AT LEAST IN
THE SOUTH. COVERAGE IS LIKELY TO BE LOW AS WITH THE PREVIOUS
SYSTEM THAT TOOK A SIMILAR PATH.
GFS/ECMWF BOTH SHOW THAT BY SUNDAY MORNING A 500MB LOW OVER NEW
YORK/NEW ENGLAND STARTS DROPPING SOUTH SOUTHWEST...REACHING
MISSISSIPPI BY WEDNESDAY. THE ECMWF STALLS THIS LOW OVER THE
LOWER MISSISSIPPI VALLEY...BUT THE GFS PUSHES IT WESTWARD ACROSS
NORTH TX THU/FRI. IF THE LOW DOES MOVE INTO THE AREA...IT IS
PROBABLY THE BEST CHANCE FOR MORE WIDESPREAD PRECIPITATION. THIS
FAR OUT...HAVE KEPT THE POPS LOW AND WE WILL WAIT FOR A BETTER
CONSENSUS. 84
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 101 79 101 78 100 / 20 20 20 20 10
WACO, TX 99 78 100 76 100 / 5 5 5 5 10
PARIS, TX 100 76 100 75 96 / 20 20 30 30 20
DENTON, TX 101 78 102 76 100 / 20 20 20 20 10
MCKINNEY, TX 100 78 101 76 99 / 20 20 30 30 10
DALLAS, TX 100 81 101 80 100 / 20 20 20 20 10
TERRELL, TX 99 78 100 76 99 / 20 20 20 20 10
CORSICANA, TX 99 77 100 76 100 / 10 10 10 10 10
TEMPLE, TX 98 75 99 74 100 / 5 5 5 5 5
MINERAL WELLS, TX 101 75 101 73 101 / 10 10 10 10 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
352 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 317 PM EDT WEDNESDAY...
A SERIES OF WEAK DISTURBANCES ALOFT WILL CROSS THE MIDDLE ATLANTIC
REGION THIS AFTERNOON INTO TONIGHT. A STRONGER UPPER LEVEL TROUGH
AND ASSOCIATED SURFACE COLD FRONT WILL MOVE EAST INTO THE OUR REGION
THURSDAY.
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE THIS AFTERNOON
INTO TONIGHT. WITH PWATS FROM 1.70 TO 2.0 INCHES AND A SLOW STORM
MOTION...ANY THUNDERSTORMS THAT DEVELOPS COULD BE EFFICIENT RAIN
PRODUCER. FFG VALUES REMAIN VERY LOW FROM RECENT HEAVY RAINFALL.
GIVEN THE VERY WET ANTECEDENT SOIL CONDITIONS ACROSS THE REGION FROM
THE PAST TWO WEEKS OF EXCESSIVE RAINFALL. DECIDED TO POST A FLASH
FLOOD WATCH FOR THE WEST UNTIL 2 AM WITH HIGHER RAINFALL RATES ONE
TO TWO POSSIBLE. A STRONGER THUNDERSTORM IS POSSIBLE INTO THIS
EVENING WITH POTENTIAL FOR GUSTY WINDS AND HAIL.
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 /20Z WEDNESDAY THROUGH MONDAY/...
AS OF 145 PM EDT WEDNESDAY...
SCATTERED MVFR SHOWERS AND THUNDERSTORMS WILL MOVE EAST ACROSS
THE REGION TONIGHT INTO THURSDAY...AS UPPER TROUGH DEEPENS ACROSS
THE GREAT LAKES REGION.
EXPECT MORE WIDESPREAD MVFR/ISOLATED IFR CIGS TO DEVELOP MANY
SITES AFT 00Z IN SHRA AND ISOLD TSRA...WHICH SHOULD PERSIST
THROUGHOUT THE NIGHT. WINDS REMAINING SW5-7KTS THROUGH THE TAF
VALID PERIOD.
MEDIUM TO HIGH CONFIDENCE IN CIGS THROUGH TAF VALID PERIOD.
MEDIUM TO HIGH CONFIDENCE IN VSBYS THROUGH TAF VALID
PERIOD...EXCEPT LOW TO MEDIUM CONFIDENCE IN THUNDERSTORMS.
HIGH CONFIDENCE IN WIND SPD/DIR THROUGH TAF VALID PERIOD.
EXTENDED AVIATION DISCUSSION...
LATEST MODELS CONTINUE TREND OF PUSHING CONVECTION MOSTLY INTO THE
PIEDMONT THURSDAY...BUT EXPECT LINGERING SHRA/ISOLD TSRA FURTHER
WEST. PERIODS OF MVFR-IFR CIGS APPEAR LIKELY EARLY THU...IMPROVING
TO MVFR-VFR BY AFTERNOON. MUCH IMPROVED AVIATION CONDITIONS APPEAR
IN THE OFFING FOR FRI-SAT AS SFC HIGH PRESSURE BUILDS DOWN FROM
THE NORTH AND HIGH PRESSURE ALOFT BUILDS TO THE NORTH OF THE AREA.
MODELS CONTINUE TO KEEP THE DEEPER MOISTURE AND ASSOCIATED TSRA
ACTIVITY WELL SOUTH OF THE AREA DURING THIS TIME FRAME.
THUS...MOSTLY VFR CONDITIONS ARE EXPECTED OUTSIDE OF TYPICAL 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/RAB
SHORT TERM...PM
LONG TERM...PM
AVIATION...KK/RAB
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
318 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 317 PM EDT WEDNESDAY...
A SERIES OF WEAK DISTURBANCES ALOFT WILL CROSS THE MIDDLE ATLANTIC
REGION THIS AFTERNOON INTO TONIGHT. A STRONGER UPPER LEVEL TROUGH
AND ASSOCIATED SURFACE COLD FRONT WILL MOVE EAST INTO THE OUR REGION
THURSDAY.
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE THIS AFTERNOON
INTO TONIGHT. WITH PWATS FROM 1.70 TO 2.0 INCHES AND A SLOW STORM
MOTION...ANY THUNDERSTORMS THAT DEVELOPS COULD BE EFFICIENT RAIN
PRODUCER. FFG VALUES REMAIN VERY LOW FROM RECENT HEAVY RAINFALL.
GIVEN THE VERY WET ANTECEDENT SOIL CONDITIONS ACROSS THE REGION FROM
THE PAST TWO WEEKS OF EXCESSIVE RAINFALL. DECIDED TO POST A FLASH
FLOOD WATCH FOR THE WEST UNTIL 2 AM WITH HIGHER RAINFALL RATES ONE
TO TWO POSSIBLE. A STRONGER THUNDERSTORM IS POSSIBLE INTO THIS
EVENING WITH POTENTIAL FOR GUSTY WINDS AND HAIL.
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 430 AM EDT WEDNESDAY...
COLD FRONT ENTERING MUCH OF THE REGION MIDDAY THURSDAY...WITH
SHOWERS/STORMS/CLOUDS WELL OUT AHEAD OF IT...COULD LIMIT ANY
STRONGER THUNDERSTORMS TO SOUTHSIDE VIRGINIA AND THE NC PIEDMONT.
STILL COULD ENCOUNTER SOME WATER PROBLEMS FOR THE FIRST HALF OF THE
DAY THURSDAY THROUGH NW NC/EXTREME SW VA/SE WEST VA AFTER HEAVY RAIN
ON WEDNESDAY. DRY AIR PUNCHES IN QUICKLY BEHIND THE BOUNDARY WITH RH
TO ABOUT 40 PERCENT AT H7 BY THE AFTERNOON ACROSS THE NEW RIVER
VALLEY. FRONT HANGS UP ACROSS THE EXTREME SOUTHEAST CWA AS IT
ENCOUNTERS THE WESTERN ATLANTIC RIDGE. THUS...LEFT HIGHER POPS WELL
INTO THE NIGHT ACROSS THOSE PARTS. ALL GUIDANCE SHOVES THE PRECIP
OUT OF OUR SOUTHEAST BY FRIDAY AFTERNOON...WHICH IS A QUICKER
SOLUTION THAN SOME OF THE PREVIOUS RUNS. WINDS VEER TO THE SE AND S
ON SATURDAY RETURNING MORE MOISTURE IN THE MID LEVELS AND FOR NOW
SLT CHC POPS ACROSS THE SOUTHEASTERN CWA. CONSIDERING THE STRENGTH
OF THE TROUGH AND H85 TEMPS AS COLD AS +11C...DID GO A FEW DEGREES
COOLER THAN GUIDANCE ON HIGHS AND LOWS THROUGH THE PERIOD.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 1225 PM EDT TUESDAY...
PATTERN OVER OUR AREA WILL REMAIN SOMEWHAT UNSETTLED. WE ARE LOOKING
AGAIN AT A FRONT SITUATED OVER THE COAST OF NC SOUTHWEST INTO
GEORGIA FRIDAY NIGHT INTO SATURDAY TO STAY IN THIS GENERAL AREA
THROUGH THE WEEKEND. MEANWHILE...WE HAVE SFC HIGH BUILDING SWD FROM
THE NE AND MID ATLANTIC. QUESTION REMAINS WHERE THE BULK OF THE
DEEPER MOISTURE WILL LIE. MODEL TRENDS HAVE FAVORED THAT MOST OF THE
AREA WILL BE SOMEWHAT DRIER WHILE THE SRN CWA STAYS CLOSER TO THE
SFC FRONT AND MORE THREAT OF SHOWERS AND STORMS. ALOFT...THE TROUGH
AXIS LIES ACROSS THE MID ATLANTIC COAST AND SW OVER THE NW GULF OF
MEXICO. DURING THIS TIME WILL HAVE TO WATCH HOW TS CHANTAL TRACKS.
WPC/NHC SHOWING BY SUNDAY INTO MONDAY THAT CHANTAL WILL MOVE TOWARD
EASTERN COAST OF FLORIDA. DURING THIS TIME THE SFC AND LOW LVL FLOW
WILL BE OFF THE ATLANTIC COAST INTO OUR AREA AND WILL ENHANCE THE
THREAT FOR SHOWERS AND STORMS WITH MONDAY STARTING TO LOOK LIKE THE
WETTER DAY. STILL WE WILL HAVE TO WATCH HOW THINGS TREND AS MODELS
STILL VARY SOMEWHAT STRENGTH AND POSITION OF UPPER LOW.
GOING INTO TUESDAY...THE 00Z ECMWF WEAKENS THE UPPER LOW AS IT MOVES
ACROSS OUR CWA WHILE THE LATEST GFS SHOWS UPPER LOW HANGING ON AND
STRONG AS IT MOVES INTO NC. GIVEN THIS WILL KEEP AT LEAST A HIGH
CHANCE...50 PERCENT FOR SHOWERS.
DURING THIS TIME...THE TEMPERATURES ARE GOING BE SEASONAL...WITH
HIGHS JUST BELOW NORMAL OVERALL AND LOWS STAYING MILDER.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
AS OF 145 PM EDT WEDNESDAY...
SCATTERED MVFR SHOWERS AND THUNDERSTORMS WILL MOVE EAST ACROSS
THE REGION TONIGHT INTO THURSDAY...AS UPPER TROUGH DEEPENS ACROSS
THE GREAT LAKES REGION.
EXPECT MORE WIDESPREAD MVFR/ISOLATED IFR CIGS TO DEVELOP MANY
SITES AFT 00Z IN SHRA AND ISOLD TSRA...WHICH SHOULD PERSIST
THROUGHOUT THE NIGHT. WINDS REMAINING SW5-7KTS THROUGH THE TAF
VALID PERIOD.
MEDIUM TO HIGH CONFIDENCE IN CIGS THROUGH TAF VALID PERIOD.
MEDIUM TO HIGH CONFIDENCE IN VSBYS THROUGH TAF VALID
PERIOD...EXCEPT LOW TO MEDIUM CONFIDENCE IN THUNDERSTORMS.
HIGH CONFIDENCE IN WIND SPD/DIR THROUGH TAF VALID PERIOD.
EXTENDED AVIATION DISCUSSION...
LATEST MODELS CONTINUE TREND OF PUSHING CONVECTION MOSTLY INTO THE
PIEDMONT THURSDAY...BUT EXPECT LINGERING SHRA/ISOLD TSRA FURTHER
WEST. PERIODS OF MVFR-IFR CIGS APPEAR LIKELY EARLY THU...IMPROVING
TO MVFR-VFR BY AFTERNOON. MUCH IMPROVED AVIATION CONDITIONS APPEAR
IN THE OFFING FOR FRI-SAT AS SFC HIGH PRESSURE BUILDS DOWN FROM
THE NORTH AND HIGH PRESSURE ALOFT BUILDS TO THE NORTH OF THE AREA.
MODELS CONTINUE TO KEEP THE DEEPER MOISTURE AND ASSOCIATED TSRA
ACTIVITY WELL SOUTH OF THE AREA DURING THIS TIME FRAME.
THUS...MOSTLY VFR CONDITIONS ARE EXPECTED OUTSIDE OF TYPICAL 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/RAB
SHORT TERM...KM
LONG TERM...WP
AVIATION...KK/RAB
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
313 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 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1130 AM CDT WED JUL 10 2013
HIGH PRESSURE WILL DRIFT SOUTHEAST ACROSS THE REGION TODAY/TONIGHT.
ENOUGH OF A PRESSURE GRADIENT AND DAYTIME MIXING TO PRODUCE GUSTY
CONDITIONS FOR THE AFTERNOON HOURS...BUT WINDS SHOULD LIGHTEN UP
QUICKLY TOWARD SUNDOWN. LIGHT WIND REGIME WILL THEN PERSIST THROUGH
MUCH OF THU. COULD SEE A FEW MID/HIGH CLOUDS THIS EVENING...AND SOME
CU FOR THU AFTERNOON. OVERALL...VFR CONDITIONS ARE EXPECTED INTO
FRIDAY.
ONE ITEM OF INTEREST IS AN UPPER LEVEL SHORTWAVE TROUGH THAT IS
EXPECTED TO DROP SOUTHEAST OUT OF CANADA AND ACROSS THE REGION
TONIGHT. IT COULD BRING SOME MID LEVEL CLOUDINESS FOR A SHORT
PERIOD...AND PERHAPS SOME SHRA--. DON/T EXPECT A REDUCTION TO
VSBY...ACCUMULATIONS...OR CHANGE FROM VFR CONDITIONS. NOT CONFIDENT
ENOUGH TO INCLUDE A MENTION IN THE TAFS QUITE YET EITHER. SOMETHING
TO MONITOR.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1139 PM CDT TUE JUL 9 2013
.UPDATE...
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
INSTABILITY 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.
&&
.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...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1139 PM CDT TUE JUL 9 2013
MAIN AVIATION CONCERN IS WINDS.
A COLD FRONT STRETCHING FROM NEAR EAU CLAIRE WI TO MANKATO MN AT
05Z WILL MOVE THROUGH THE TAF SITES DURING THE NEXT FEW HOURS...
SWINGING WINDS AROUND TO THE NORTHWEST AND MAINTAINING A BREEZE
AROUND 10 KT. WINDS COULD GUST BRIEFLY WITH THE PASSAGE...
ESPECIALLY AT KRST AND INCLUDED A TEMPO GROUP FROM 06-08Z THERE
FOR GUSTS OF 23 KT. GUSTS ARE EXPECTED AT BOTH TAF SITES DURING
THE DAYTIME HOURS WITH A TIGHT PRESSURE GRADIENT IN PLACE AHEAD OF
HIGH PRESSURE BUILDING EAST FROM THE DAKOTAS. THESE GUSTS SHOULD
RANGE FROM 15-20 KT. PLAN ON THE WINDS TO DIMINISH THROUGH THE
EVENING AS DAYTIME MIXING SUBSIDES AND THE HIGH MOVES CLOSER.
DRY AIR IN THE LOWER LEVELS OF THE ATMOSPHERE ACCOMPANYING THE
HIGH PRESSURE AREA WILL HELP TO KEEP CONDITIONS VFR THROUGH THE
TAF PERIOD.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...AJ
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS TUCSON AZ
930 PM MST THU JUL 11 2013
.SYNOPSIS...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...MUCH QUIETER EVENING ACROSS SOUTHEAST ARIZONA WITH
BULK OF SCATTERED STORMS OCCURRING THIS AFTERNOON. NO STORMS ATTM
ACROSS SE ARIZONA...BUT THERE ARE SCATTERED STORMS SOUTH OF THE NEW
MEXICO BOOT. EARLIER RUNS OF THE HRRR MODEL HAD THEM STORMS PUSHING
INTO THE EASTERN ZONES LATER TONIGHT. HOWEVER THE LAST COUPLE OF
RUNS HAS BACKED OFF OF THIS IDEA. IN ANY EVENT...WILL KEEP A CHANCE
OF STORMS ACROSS COCHISE...GRAHAM AND GREENLEE COUNTIES OVERNIGHT
WITH A SLIGHT CHANCE AS FAR WEST AS TUCSON. UPDATED TO FORECAST DUE
OUT SHORTLY. CHECK PREVIOUS DISCUSSION BELOW FOR DETAILS ON FRIDAY
FORECAST AND BEYOND.
POSTED ON OUR WEBSITE...FACEBOOK AND TWEETED 2013 MONSOON RAINFALL
AMOUNTS THROUGH TODAY. SOME AREAS ALREADY IN JULY TOP 10 WETTEST ON
RECORD. CHECK IT OUT.
&&
.PREVIOUS DISCUSSION...
FOR TOMORROW...MOISTURE PROFILE LOOKS LESS PROMISING. NAM SHOWS
DRYING AT ALL LEVELS ESPECIALLY ABOVE 700 MB. THIS MAKES SENSE GIVEN
THE CURRENT WV IMAGERY SHOWING DRY AIR OVER THE GREAT PLAINS WHICH
SHOULD CYCLE INTO ARIZONA BY THIS TIME TOMORROW. THEN AS THE RIDGE
SLIDES EAST...ANY CHANCE OF RECYCLING SOME OF OUR MID LEVEL MOISTURE
LOOKS SLIM. WE WILL NEED TO RELY ON OUR OLD FAITHFUL SOURCES OF
MONSOON MOISTURE...AND GIVEN THE PERSISTENT LOW LEVEL FLOW OUT OF
THE SOUTH TO SOUTHEAST THIS WEEKEND...I DO ANTICIPATE SOME MOISTURE
AVAILABLE FOR AFTERNOON CONVECTION. IT JUST APPEARS THE POTENTIAL
FOR WIDESPREAD HEAVY RAIN DIMINISHES THROUGH THE WEEKEND. THIS
SHOULD ALSO TRANSLATE INTO A WARMING TREND WITH HIGHS RAMPING UP A
FEW DEGREES ABOVE NORMAL BY SUNDAY AND MONDAY.
NOW FOR THE BIG CHANGES FROM YESTERDAY. MODELS WERE SHOWING A LOVELY
INVERTED TROUGH REACHING ARIZONA LATE MONDAY LASTING THROUGH THE
MIDDLE OF NEXT WEEK. TODAY...THE CONSENSUS AMONG THE DETERMINISTIC
AND ENSEMBLE MEAN RUNS OF THE GFS AND ECMWF SHOW AN INTERESTING
EVOLUTION TO THE UPPER FLOW. OUR MAIN MONSOON RIDGE SPLITS INTO TWO
LOBES WITH ONE HIGH OVER THE GREAT LAKES REGION AND THE SECOND HIGH
OVER THE SOUTHWEST U.S.. OUR INVERTED TROUGH THEN TAKES THE PATH OF
LEAST RESISTANCE INTO THE LOWER PRESSURE BETWEEN THE TWO HIGHS. SO
WE END UP WITH AN EASTERLY WAVE...OR INVERTED TROUGH...AT ABOUT 40
DEG NORTH LATITUDE. THAT IS PRETTY FAR NORTH FOR AN EASTERLY MOVING
TROUGH...BUT IT DOES HAPPEN ON OCCASION. AZ WOULD THEN SIT UNDER
NORTHEAST FLOW ALOFT STARTING AROUND TUESDAY. THIS CAN PRODUCE AN
ACTIVE PATTERN WITH ROUTINE CONVECTION AND POSSIBLE FLOODING
CONCERNS IF THE MOISTURE IS PRESENT. THEN...ONCE THE INVERTED TROUGH
REACHES AZ BY THURSDAY...THE IMPROVED INSTABILITY COULD HELP STORMS
LINGER THROUGH OVERNIGHT HOURS.
THE BIG CAVEAT IS THAT THESE SOLUTIONS ARE IN THE EXTENDED RANGES OF
THE CURRENT FORECAST PERIOD SO A LOT CAN CHANGE. BUT CERTAINLY THIS
FEATURE IS WORTH WATCHING FOR THE MID TO END OF NEXT WEEK.
&&
.AVIATION...ANY SHOWERS AND THUNDERSTORMS OVERNIGHT WILL GENERALLY
BE EAST OF KTUS. FOR FRIDAY...EXPECT SCATTERED AFTERNOON
THUNDERSTORMS TO RETURN TO THE AREA. GUSTY AND ERRACTIC WINDS NEAR
STORMS. OTHERWISE SURFACE WINDS DIURNALLY DRIVEN LESS THAN 10 KTS.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...SCATTERED MAINLY 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. THROUGH FRIDAY...DAYTIME
RELATIVE HUMIDITIES WILL RANGE FROM THE 20S TO 40S WITH GOOD
NIGHTTIME RECOVERIES THROUGH THEN THERE WILL BE A SLIGHT DRYING
TREND THIS WEEKEND.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
349 AM EDT Fri Jul 12 2013
.NEAR TERM [Today]...
An unseasonably deep trough at upper levels is once again digging
southward over the eastern half of the U.S., and will stretch from
the Great Lakes to the northern Gulf of Mexico by this afternoon.
Just ahead of this feature, high PWAT values (above 2") are being
drawn into our region from the Gulf. In addition, a stationary
front near our CWA will provide enough forcing to enhance
precipitation chances through the period.
This front is currently located near the northern edge of our CWA,
and has led to the development of some showers in our SW Georgia
counties, which should continue throughout the overnight hours.
Also, scattered showers and thunderstorms will continue to develop
around coastal regions of the Big Bend and our marine zones. With
daytime heating and as the front sags southward into our region
later today, showers and thunderstorms will increase in coverage. CAM
models and the HRRR both show convection developing by the late
morning hours in the Big Bend region and into south central
Georgia, and then spreading to other parts of the CWA later in the
afternoon. Reflected this pattern within the high temperatures,
showing low 90s in our NW counties tapering to mid-upper 80s in
our SE counties, where there is a higher chance of precipitation.
&&
.SHORT TERM [Tonight Through Sunday]...
There is good agreement among the latest NWP guidance in taking the
aforementioned mid-upper level low pressure system from eastern KY
tonight, to OK by Sunday night. As a deep layer subtropical ridge
fills in westward behind this low, moist southeast flow will develop
across our forecast area. Although the Precip Water values are
likely to continue above climatology through the weekend, the best
Q-G forcing is expected to be on Saturday, which is when we forecast
our highest PoP (50-70%). With such a moisture-rich environment,
convection could develop almost anytime on Saturday. On Sunday the
forcing for convection will have to come from mesoscale features
(sea breeze and outflow boundary interactions), so we expect more of
a diurnal cycle to the rain, along with a slightly low PoP (40-50%).
High temperatures will be a few degrees below climo, especially
Saturday.
.LONG TERM [Sunday Night through Thursday]...
The long wave pattern will be in retrogression through much of this
period. An upper low will track from the Midwest to the Central or
Southern Plains (depending on the model you pick) as a ridge pushes
in from the Atlantic. Beneath this ridge, a TUTT will track west
across FL Monday night through Wednesday. At the surface, a front
will lift north across the region on Sunday with the subtropical
"Bermuda" ridge axis mainly north of the area after that. That will
put the area in an easterly flow regime at lower levels. Typical mid
range PoPs are expected through the period with development largely
driven by land and sea breeze circulations. Max temps will be a
couple of degrees below normal with mins close to normal.
&&
.Aviation [Through 06Z Saturday]...
Due to the stationary front stalled just north of our region, widely
scattered areas of showers and possibly a thunderstorm will persist
through the overnight hours in some parts of our region, especially
SW Georgia. VFR conditions are expected at most terminals for the
rest of the evening, although IFR or LIFR conditions are
possible where any low ceilings and fog occur. Ceilings and
visibilities will likely lower in the early morning hours at all
terminals due to the moist conditions and light winds, but ample
cloud cover will likely prevent the formation of widespread fog.
Scattered showers and thunderstorms could increase in coverage
during the late morning hours near TLH and VLD, and will be
possible at all terminals in the afternoon and early evening. IFR
conditions will likely occur in any thunderstorms, but elsewhere
VFR conditions should persist.
&&
.MARINE...
The 00 UTC NAM, and to a lesser extent the GFS, forecast a fairly
well-defined cyclonic circulation to develop in our coastal waters
tonight and Saturday. The ECMWF and SREF mean wind fields have a
much more subtle wind shift associated with a trough, which is the
solution preferred for this forecast cycle. This will keep our winds
and seas below exercise caution levels. If the NAM or GFS were to
verify, however, our wind & seas forecast would be too low. However,
these models (especially the NAM) have a tendency to wind up low
pressure systems too much when there is warm water.
&&
.FIRE WEATHER...
With moist southerly flow to continue through the weekend, no fire
weather concerns are expected. While some drier air is anticipated
to return by Tuesday, RH values should still remain above critical
thresholds.
&&
.HYDROLOGY...
All river points that have been in flood continue to recede, albeit
a little slowly on the lower Choctawhatchee, where Caryville and
Bruce will remain at flood stage for some time. Routed flows from
the Withlacoochee and Alapaha Rivers are progressing downstream and
are now beginning to initiate rises in the lower portions of these
rivers and into the Middle Suwannee. There is considerable capacity
in the Suwannee Basin, so baring significant rainfall, flooding is
not anticipated along the Middle Suwannee, though flows may approach
action stage by the middle of next week at Ellaville and Dowling
Park. It is helpful that routed flows from the Upper Suwannee remain
relatively low, as the bulk of the expected rise on the Middle
Suwannee is occurring from the Withlacoochee and Alapaha Rivers.
The rainfall over this weekend is expected to average aerially
around 2 to 3 inches, with isolated heavier totals possible. This
certainly does not look to be like the significant flooding
rainfall we saw last week, and as a result, widespread flooding is
not anticipated. However, given the wet soil conditions across much
of North Florida and Southern Georgia, a couple of inches of rain in
a short amount of time could easily generate localized flooding,
especially in an urban environment. Expected rainfall could keep
rivers currently in flood at those levels well into next week (like
the Choctawhatchee) and could result in basins like the Ochlockonee
or Chipola nearing flood stage depending on the location of the
heaviest rains.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 87 71 88 71 90 / 70 40 60 40 50
Panama City 87 75 85 73 87 / 70 40 50 30 40
Dothan 90 72 88 72 89 / 50 30 50 30 40
Albany 89 71 87 72 90 / 60 30 60 30 50
Valdosta 89 71 90 71 94 / 70 50 70 40 50
Cross City 86 72 88 71 90 / 70 50 70 40 60
Apalachicola 86 74 84 74 87 / 70 50 60 30 50
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...Godsey/Lahr
SHORT TERM...Fournier
LONG TERM...Wool
AVIATION...GodseyLahr
MARINE...Fournier
FIRE WEATHER...Godsey/Lahr
HYDROLOGY...Godsey
AREA FORECAST DISCUSSION
NWS MIAMI FL
203 AM EDT FRI JUL 12 2013
.AVIATION...
DURING THE EARLY MORNING HOURS...ALL EAST COAST SITES ASSIGNED
VCSH AS SHOWERS CONTINUE TO FORM ACROSS THE NEAR SHORE ATLANTIC
WATERS. TERMINALS KTMB...KMIA AND KOPF MAY EXPERIENCE PASSING
SHOWERS OVER THE NEXT COUPLE OF HOURS WITH BRIEF SUB-VFR
CONDITIONS POSSIBLE...WILL AMEND IF NEEDED BUT PREVAILING VFR
EXPECTED. TERMINAL KAPF EXPECTED TO MAINTAIN VFR THROUGH EARLY MORNING
HOURS. BY MID-MORNING THROUGH THE AFTERNOON...THERE IS A LOT OF
UNCERTAINTY IN THE FORECAST...INCLUDING THE SURFACE WIND FORECAST
AS THE REMNANTS OF CHANTAL CONTINUES TO MOVE NORTH OF THE CUBAN
COAST TOWARDS THE CENTRAL BAHAMAS. AS THIS FEATURE MOVES NORTHWARD
INTO THE NORTHWEST BAHAMAS LATER TODAY...TROPICAL MOISTURE AND
POTENTIAL FOR CONVECTION IS EXPECTED BY THE LATE MORNING INTO THE
AFTERNOON. ALL EAST COAST TERMINALS ASSIGNED VCTS BY 15Z. FOR THE
WIND FORECAST...AROUND 13Z TO 15Z TIME FRAME A LIGHT SOUTHERLY TO
SOUTHWESTERLY FLOW IS FORECAST ACROSS THE REGION...INCLUDING THE
EAST COAST TERMINALS. AROUND 19Z AN EAST COAST SEA BREEZE COULD
TRY TO DEVELOP WHICH WOULD GIVE MOST OF THE EAST COAST TERMINALS A
SSE WIND DIRECTION AROUND 8 KNOTS. BUT NEED TO STRESS THE
UNCERTAINTIES. THE MOST ACTIVE AREAS OF CONVECTION IS EXPECTED TO
BE ACROSS THE ATLANTIC WATERS AND THE EASTERN HALF OF THE
PENINSULA WITH NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS
EXPECTED WITH BRIEF PERIODS OF IFR CONDITIONS POSSIBLE WITH
SHOWERS/THUNDERSTORMS.
60
&&
.PREV DISCUSSION... /ISSUED 947 PM EDT THU JUL 11 2013/
UPDATE...
SLIGHT CHANGES WERE DONE TO THE FIRST PERIOD OF THE FORECAST
PACKAGE TO MATCH WITH THIS EVENING`S WEATHER PATTERN. LATEST MODEL
GUIDANCE CONTINUES TO SHOW THE REMNANTS OF CHANTAL REMAINING
OFFSHORE ACROSS THE ATLANTIC OVERNIGHT...WHICH COINCIDES WITH
PREVIOUS MODELS RUNS. 00Z SOUNDING DEPICTING A LIGHT EASTERLY FLOW
AT LOW LEVELS...WHICH COULD HELP BRINGING A FEW SHOWERS THROUGH
THE NIGHT ACROSS THE PENINSULA. CURRENT FORECAST SHOWING EXACTLY
THIS TREND...THEREFORE NO CHANGES WERE NEEDED.
PREV DISCUSSION... /ISSUED 801 PM EDT THU JUL 11 2013/
AVIATION...
THE WEATHER SHOULD REMAIN DRY TONIGHT OVER ALL OF THE TAF SITES
ACROSS SOUTH FLORIDA ALONG WITH LIGHT AND VARIABLE WINDS. THE
WINDS WILL THEN BECOME SOUTHWEST ON FRIDAY AT 5 TO 10 MPH IN THE
MORNING WITH A SLIGHT CHANCE OF SHOWERS. THE EAST COAST SEA BREEZE
SHOULD DEVELOP LATE IN THE DAY AND PUSH INLAND TO ABOUT THE KFXE
AND KTMB TAF SITES BETWEEN 19Z AND 20Z. SO WILL MAKE THE WINDS BE
BETWEEN 170 AND 190 ALONG THE EAST COAST TAF SITES BETWEEN 19Z AND
20Z ON FRIDAY. THERE WILL ALSO BE THE CHANCE OF THUNDERSTORMS
ALONG THE EAST COAST TAF SITES AFTER 19Z. SO HAVE ADDED VCTS TO
THE EAST COAST TAF SITES AFTER 19Z ON FRIDAY. THE CEILING AND VIS
SHOULD REMAIN IN THE VFR CONDITIONS AT ALL OF THE TAF SITES
TONIGHT INTO FRIDAY.
AVIATION..54/BNB
PREV DISCUSSION... /ISSUED 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 89 75 88 75 / 60 30 60 30
FORT LAUDERDALE 89 78 89 77 / 60 30 60 30
MIAMI 89 77 88 78 / 60 30 60 30
NAPLES 87 74 89 74 / 30 30 40 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...57/DG
AVIATION/RADAR...60/BD
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
128 AM EDT FRI JUL 12 2013
.PREV DISCUSSION... /ISSUED 940 PM EDT THU JUL 11 2013/
UPDATE...
MCV CONTINUES TO ROTATE SHOWERS AND THUNDERSTORMS MAINLY ACROSS THE
SOUTHERN TIER OF THE CWA THIS EVENING. CONVECTION SHOULD GRADUALLY
PERTAIN TO THE SOUTHEASTERN PORTION OF THE AREA INTO MORNING...WHILE
THE FRONT PUSHES INTO NORTH GEORGIA. THIS FRONT HAS BEEN TRIGGERING
SOME ISOLATED THUNDERSTORMS AND SHOWERS...THOUGH NOT AS WIDESPREAD
AS IN THE SOUTH. LOCAL WRF AND HRRR SOLUTIONS SUGGEST A BAND OF
CONVECTION MAY DEVELOP AFTER MIDNIGHT FROM THE ATHENS TO ATLANTA
AREA...THOUGH CONFIDENCE IS NOT HIGH IN THIS PLAYING OUT AT THE
MOMENT. THERE IS AN INSTABILITY AXIS NEAR THIS AREA WHICH COULD
SERVE TO FOCUS THE DEVELOPMENT BUT WILL CONTINUE TO WATCH TRENDS.
ALL CONSIDERED...HAVE KEPT LIKELY POPS SOUTHEAST AND CHANCE POPS
ELSEWHERE TONIGHT. HAVE ALSO KEPT CURRENT FLASH FLOOD WATCH SET TO
EXPIRE AT 04Z FOR NORTH GA AND 06Z SOUTH. OTHERWISE MADE ONLY
MINOR TWEAKS TO TEMP...DEWPT...AND SKY TRENDS. PREVIOUS DISCUSSION
FOLLOWS...
BAKER
PREV DISCUSSION... /ISSUED 818 PM EDT THU JUL 11 2013/
PREV DISCUSSION... /ISSUED 353 PM EDT THU JUL 11 2013/
SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
SHOWERS AND ISOLATED THUNDERSTORMS BEGINNING TO POP ACROSS THE AREA.
MAIN FRONTAL BOUNDARY IS STILL ACROSS TN BUT IT IS MOVING SLOWLY
SOUTH. THIS FRONT SHOULD MOVE INTO NW GA WITHIN THE NEXT FEW
HOURS. THESE SHOWERS AND THUNDERSTORMS ARE STAYING FAIRLY WEAK AND
NOT MOVING VERY MUCH...SO WILL KEEP AN EYE OUT FOR ANY FLOODING
CONCERNS. THERE IS ALSO LESS INSTABILITY ACROSS THE AREA FOR THESE
STORMS TO WORK WITH TODAY SO THEY SHOULD STAY BELOW SEVERE
CRITERIA. THERE MAY BE A STORM OR TWO THAT GETS CLOSE TO SEVERE
NEAR 00Z WHEN THE INSTABILITIES PEAK...SO WILL HAVE TO CONTINUE TO
MONITOR THIS AS WELL. AS THE FRONT MOVES SOUTH IT WILL WILL USHER
IN SOME DRIER AIR AND SHOULD HELP TO KEEP PRECIPITATION DOWN TO A
MINIMUM ESPECIALLY ACROSS NORTH GA FRIDAY. THIS FRONT WILL ALSO
FINALLY PUSH THE MAIN MOISTURE PLUME THAT HAS BEEN OVER THE AREA
FOR THE PAST FEW WEEKS EAST OF THE STATE. THIS DRIER AIR WILL BE
SHORT LIVED AS THE MOISTURE BEGINS TO RETROGRADE WESTWARD SAT
MORNING.
01
LONG TERM /SATURDAY THROUGH THURSDAY/...
NO MAJOR CHANGES MADE TO THE EXTENDED PERIODS AS LONG RANGE MODELS
CONTINUE TO SHOW FAIRLY GOOD AGREEMENT WITH A FRONTAL BOUNDARY
LINGERING ACROSS CENTRAL GA ON SATURDAY... THEN PUSHING NORTH AND
SPREADING DEEPER MOISTURE BACK ACROSS NORTH GA ON SUNDAY. AS A
RESULT... EXPECT DECREASED STORM COVERAGE/THREAT ACROSS MUCH OF
NORTH GA ON SATURDAY... WITH SCATTERED AFTERNOON AND EVENING
STORMS STILL LIKELY ACROSS CENTRAL GA NEARER THE FRONT. BUT THIS
CONVECTIVE BREAK ACROSS NORTH GA WILL BE SHORT-LIVED AS RETURNING
DEEP LAYER MOISTURE BEHIND THE ADVANCING WARM-FRONT WILL ALSO
RETURN THE STORM AND POTENTIAL LOCALLY HEAVY RAIN THREAT BACK TO
NORTH GA BY SUNDAY AFTERNOON. THE ECMWF AND GFS SHOW AMAZING
AGREEMENT WITH A LARGE UPPER RIDGING SETTLING OVER THE OHIO VALLEY
REGION BY MONDAY AND HELPING TO FINALLY SHUNT THE DEEPER MOISTURE
AND GREATER STORM THREAT SOUTHWARD INTO SOUTH GA FOR MON-THU.
HOWEVER... STILL EXPECT SUFFICIENT LOW LEVEL MOISTURE AND DAYTIME
INSTABILITIES TO SUPPORT LOW SCATTERED COVERAGE OF AFTERNOON AND
EVENING STORMS EACH DAY. /39
PREV LONG TERM DISCUSSION... /ISSUED 409 AM EDT THU JUL 11 2013/
LONG TERM /SATURDAY THROUGH WEDNESDAY/...
EXTENDED BEGINS WITH CLOSED UPPER LOW VICINITY OF OHIO VALLEY WITH
SOME DRIER AIR ACROSS NORTH GA. GFS/ECMWF DIFFER IN GENERAL
LOCATION OF THE UPPER LOW...BUT BOTH RETROGRADE IT WESTWARD DURING
THE PERIOD. WITH THE UPPER RIDGE LOCATED OFF THE MID ATLANTIC
COAST...THE CWA REMAINS IN AN EASTERLY FLOW OF MOISTURE FROM THE
ATLANTIC. THIS WILL KEEP US IN A PATTERN OF SHOWERS AND
THUNDERSTORMS EACH DAY AND HAVE KEPT MOST POPS IN THE CHANCE
CATEGORY. BY THE END OF THE PERIOD LOOKS LIKE THE UPPER RIDGE
BEGINS TO BUILD BACK OVER THE SOUTHEAST...SO THE PATTERN MAY
BECOME MORE DIURNAL. TWEAKED MAX TEMPERATURES DOWN A BIT MOST DAYS
DUE TO EASTERLY FLOW AND EXPECTED POPS.
HYDROLOGY...
AS BEEN THE CASE THE PAST SEVERAL DAYS...BASIN-AVERAGE QPF VALUES
ARE NOT PARTICULARLY IMPRESSIVE /BETWEEN 0.5-1 INCH NORTH AND
1-1.5 INCHES SOUTH/...BUT AGAIN THESE ARE BASIN-AVERAGE AND OF
COURSE SOME AREAS WILL GET QUITE A BIT MORE. PW VALUES ARE STILL
RANGING FROM 1.6 TO 2.0 THROUGH 12Z FRI. AS THE FRONT MOVES INTO
THE AREA FORECASTED PW`S DO COME DOWN A BIT FOR FRIDAY. SOME 6-HR
FLASH FLOOD GUIDANCE VALUES ESPECIALLY IN NORTHWEST GEORGIA ARE
LESS THAN AN INCH. SO WITH THAT...WILL KEEP THE FLASH FLOOD WATCH
THROUGH 08Z FRI. WILL ALSO CONTINUE TO KEEP OUR EXTREME SOUTHERN
COUNTIES OUT OF THE WATCH AS THEY CAN HANDLE A BIT MORE PRECIP
THAN AREAS NORTH.
&&
.AVIATION...
06Z UPDATE...
MAIN CONCERN SEEMS TO BE POTENTIAL FOR IFR-MVFR CEILINGS TO
DEVELOP THIS MORNING. POTENTIAL IS THERE BUT OVERALL CONFIDENCE IS
LOW TO MEDIUM. SOME MVFR VSBYS ALSO CAN BE EXPECTED. CONDITIONS
EXPECTED TO IMPROVE DURING THE MORNING TO VFR. CONVECTION OVER NNW
CWA EXPECTED TO DIMINISH NEXT COUPLE OF HOURS AND NOT AFFECT THE
TAFS. BEST POTENTIAL FOR CONVECTION DURING THE DAY LOOKS TO BE
OVER CENTRAL GA WITH THE BEST CHANCES AT CSG/MCN. SURFACE WINDS
LIGHT AND VARIABLE OR CALM TENDING TO BECOMING ENE DURING THE DAY.
//ATL CONFIDENCE...06Z UPDATE...
LOW CONFIDENCE ON MORNING CIGS AND IMPACTS OF ANY CONVECTION TODAY.
MEDIUM CONFIDENCE ON WIND SHIFT TO ENE.
BDL
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 87 69 84 70 / 40 30 40 40
ATLANTA 87 70 84 71 / 30 20 30 40
BLAIRSVILLE 83 64 80 66 / 20 20 20 30
CARTERSVILLE 87 68 86 70 / 20 20 20 30
COLUMBUS 89 72 88 72 / 40 30 40 40
GAINESVILLE 85 70 81 69 / 30 20 30 40
MACON 87 71 86 72 / 60 40 50 50
ROME 87 67 88 69 / 10 10 20 30
PEACHTREE CITY 87 68 84 69 / 30 20 30 40
VIDALIA 85 71 87 73 / 70 40 50 40
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 4 AM EDT EARLY THIS MORNING FOR THE
FOLLOWING ZONES: BALDWIN...BIBB...BUTTS...CHATTAHOOCHEE...
CLARKE...CLAYTON...COWETA...CRAWFORD...FAYETTE...GLASCOCK...
GREENE...HANCOCK...HARRIS...HEARD...HENRY...HOUSTON...JASPER...
JEFFERSON...JONES...LAMAR...MACON...MARION...MERIWETHER...
MONROE...MORGAN...MUSCOGEE...NEWTON...OCONEE...OGLETHORPE...
PEACH...PIKE...PUTNAM...ROCKDALE...SCHLEY...SPALDING...TALBOT...
TALIAFERRO...TAYLOR...TROUP...TWIGGS...UPSON...WALTON...WARREN...
WASHINGTON...WILKES...WILKINSON.
&&
$$
SHORT TERM...BDL
LONG TERM....41
AVIATION...BDL
AREA FORECAST DISCUSSION
NWS TOPEKA KS
320 AM CDT FRI JUL 12 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 320 AM CDT FRI JUL 12 2013
THE WEATHER PATTERN THIS MORNING DEPICTS THE MID LEVEL RIDGE AXIS
STRETCHING ACROSS THE CENTRAL AND NORTHERN PLAINS. THE RIDGE IS
EXPECTED TO EXPAND NORTHEASTWARD LATER TODAY ESSENTIALLY CUTTING OFF
THE FLOW FROM THE UPPER TROUGH ROTATING OVER THE MID ATLANTIC REGION.
AT THE 08Z HOUR A SUBTLE PERTURBATION EMBEDDED WITHIN THE RIDGE WAS
NOTED OVER SOUTHEAST WYOMING. THE LATEST HRRR AND RAP HAVE TRIED TO
GENERATE PRECIP FOR THE PREVIOUS FEW HOURS NOTING MULTIPLE WEAK
SHORTWAVE TROUGHS THAT ARE NOT OBSERVED IN REAL TIME. AND SINCE NO
FORCING IS APPARENT WILL THEREFORE MONITOR BUT MAINTAIN A DRY
FORECAST FOR THE MORNING PERIOD. A WARMER AND WINDY FRIDAY IS IN
STORE FOR NORTHEAST KANSAS. SURFACE HEATING AND A TIGHTENING
PRESSURE GRADIENT FROM THE H85 SHORTWAVE TROUGH OVER EASTERN
COLORADO WILL PICKUP SOUTHERLY WINDS BETWEEN FROM 15 TO 20 MPH.
THIS WILL ALSO INCREASE WARMER AIR FLOWING INTO THE AREA WITH
READINGS FROM THE LOW 90S IN EAST CENTRAL AREAS...TO THE UPPER 90S
OVER NORTH CENTRAL KS. MOISTURE ADVECTING NORTHWARD WILL KEEP
DEWPOINTS IN THE LOW TO MIDDLE 60S...TRANSLATING TO HEAT INDICES
BETWEEN 100 AND 105 DEGREES OVER NORTH CENTRAL KS. QUIET WEATHER
CONTINUES INTO FRIDAY EVENING WITH STEADY SOUTHEAST WINDS KEEPING
TEMPERATURES WARMER THAN THIS MORNING IN UPPER 60S TO MID 70S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 320 AM CDT FRI JUL 12 2013
FOR SATURDAY THROUGH SUNDAY NIGHT...THE MAIN FOCUS FOR THE
FORECAST IS A RETROGRADING CLOSED LOW MOVING FROM THE TN VALLEY
INTO THE SOUTHERN HIGH PLAINS. MODELS SEEM TO BE SLIGHTLY FASTER
WITH THE PROGRESSION OF THE CLOSED UPPER LOW AND BY SUNDAY NIGHT
HAVE IT OVER THE HIGH PLAINS. ALSO THE MAJORITY OF MODEL SOLUTIONS
TAKE THE UPPER LOW SOUTH OF THE FORECAST AREA WITH THE BETTER
LARGE SCALE FORCING OVER SOUTHERN KS AND OK. CURIOUSLY IT APPEARS
AS THOUGH THERE IS NOT MUCH MID LEVEL MOISTURE ACCOMPANYING THE
LOW WITH THE NAM AND GFS ACTUALLY SHOWING PWS DRYING WITH SURFACE
DEWPOINT TEMPS COOLING AS THE UPPER LOW APPROACHES. ADDITIONALLY
THE MID LEVEL LAPSE RATES ARE PRETTY CLOSE TO THE MOIST ADIABATIC
LAPSE RATE SO THERE IS LITTLE OR NO INSTABILITY ABOVE THE LCL. SO
IN GENERAL AM NOT OVERLY EXCITED ABOUT PRECIP CHANCES THROUGH THE
WEEKEND. WILL KEEP A SLIGHT CHANCE FOR SOME SHOWERS SUNDAY ACROSS
EAST CENTRAL KS THINKING THIS IS THE MOST LIKELY TIME FRAME FOR
THE UPPER LOW TO MOVE THROUGH SOUTHEAST KS. SINCE THERE DOES NOT
APPEAR TO BE ANY INSTABILITY...HAVE REMOVED THE MENTION OF THUNDER
FROM THE FORECAST FOR SUNDAY. HIGHS SHOULD BE TRENDING COOLER
THROUGH THE WEEKEND...ESPECIALLY FOR SUNDAY AS MODELS SHOW LOW
LEVEL COLD AIR ADVECTION FROM THE SOUTHEAST. HIGHS IN THE 90S FOR
SATURDAY SHOULD COOL INTO THE MID 80S TO AROUND 90 FOR SUNDAY.
LOWS WILL ALSO TREND COOLER WITH READINGS FOR SUNDAY MORNING
EXPECTED TO BE IN THE 60S AS SURFACE RIDGING FROM THE EAST
PERSISTS.
MONDAY THROUGH TUESDAY IS A LITTLE MORE UNCERTAIN AS MODELS START
TO DIVERGE ON THE TRACK OF THE CLOSED LOW. THERE IS THE
POSSIBILITY THAT THE UPPER LOW GETS HUNG UP OVER THE HIGH PLAINS
WITH PIECES OF ENERGY ROTATING NORTH INTO THE STATE. BECAUSE OF
THIS HAVE HELD ONTO SOME SLIGHT CHANCE POPS DURING THE DAY MONDAY
AND TUESDAY THINKING THERE COULD BE SOME POP UP STORMS IF THE
UPPER LOW IS JUST TO THE WEST OF THE FORECAST AREA. HIGHS ARE
FORECAST TO REMAIN NEAR NORMAL WITH READINGS AROUND 90. SOUTHERLY
WINDS AND A GRADUAL INCREASE IN LOW LEVEL MOISTURE SHOULD KEEP
LOWS AROUND 70 TO THE LOWER 70S.
THE GFS AND ECMWF SHOW WEAK MID LEVEL RIDGING NOSING INTO EASTERN
KS FROM THE EAST WITH NO REAL SURFACE FEATURE TO FOCUS LIFT OF A
SURFACE PARCEL. BECAUSE OF THIS HAVE MAINTAINED A DRY FORECAST.
TEMPS SHOULD SEE A GRADUAL WARMING TREND AS MID LEVEL HEIGHTS
RISE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1143 PM CDT THU JUL 11 2013
VFR CONDITIONS THROUGH THE PERIOD. WINDS GENERALLY EAST SOUTHEAST
AND BECOME SUSTAINED OVER 12KTS IN THE AFTERNOON HOURS BEFORE
DECREASING ONCE AGAIN NEAR SUNSET. 67
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...BOWEN
LONG TERM...WOLTERS
AVIATION...67
AREA FORECAST DISCUSSION
NWS WICHITA KS
1135 PM CDT THU JUL 11 2013
UPDATE FOR THE 06Z AVIATION SECTION.
.UPDATE...
ISSUED AT 831 PM CDT THU JUL 11 2013
OUTFLOW BOUNDARIES FROM EARLY AFTERNOON CONVECTION IN SE KS PUSHED
WELL INTO OK THIS EVENING...KEEPING ANY CONVECTIVE ACTIVITY WELL TO
THE SOUTH OF THE AREA. LATEST RUC DOES SHOW AN UNSTABLE AIRMASS
STILL ACROSS SOUTH CEN KS...BUT EML HAS CONTINUED TO WARM LEADING TO
LITTLE IF ANY CU DEVELOPMENT ACROSS SRN KS. EXPECTING WARMER TEMPS
ALOFT TO CONTINUE ACROSS THE FORECAST AREA LATE THIS EVENING AND
OVERNIGHT WHICH WILL KEEP THINGS MOSTLY CLEAR. SO WILL REMOVE
CONVECTIVE CHANCES OVER EXTREME SRN KS AND KEEP THINGS DRY
OVERNIGHT.
KETCHAM
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 246 PM CDT THU JUL 11 2013
RESIDUAL SHOWERS/STORMS WILL CONTINUE TO DRIFT SOUTHEAST THIS
AFTERNOON AND EVENING FROM MCV ALOFT...BUT SHOULD DECREASE RAPIDLY
JUST AFTER SUNSET. OTHERWISE THE HEAT AND HUMIDITY WILL BUILD BACK
OVER THE REGION FOR FRIDAY AND SATURDAY...AS THE UPPER LEVEL RIDGE
CENTER POSITIONS ITSELF OVER THE CENTRAL PLAINS. HEADING INTO SUNDAY
MODEL SOLUTIONS FOR THE PAST TWO CYCLES CONTINUE TO SHOW CURRENT
UPPER WAVE OVER THE GREAT LAKES CUTTING OFF THEN RETRO-GRADING
WESTWARD INTO KANSAS THIS PERIOD. WE WILL INTRODUCE SOME
PRECIPITATION CHANCES FOR SUNDAY AND LOWER DAYTIME TEMPERATURES A
BIT.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 246 PM CDT THU JUL 11 2013
THE UPPER LOW WILL KEEP THINGS UNSETTLED FOR MONDAY/TUESDAY WITH
SCATTERED SHOWERS AND STORMS POSSIBLE...WITH THE COVERAGE MORE
WIDESPREAD DURING THE AFTERNOON/EVENING HOURS DUE TO DAYTIME
HEATING. DAYTIME HIGHS WILL BE AROUND OR SLIGHTLY BELOW NORMAL FOR
EARLY NEXT WEEK. MEANWHILE THE UPPER LEVEL RIDGE CENTER WILL BUILD
BACK OVER THE CENTRAL PLAINS FOR MID TO LATE WEEK.
JAKUB
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1133 PM CDT THU JUL 11 2013
VFR CONDITIONS WILL CONTINUE ACROSS THE AREA...FOR THE NEXT 24
HOURS. WILL SEE CLEAR SKIES ACROSS THE AREA AS MID LEVEL TEMPS WARM
KEEPING ANY CLOUDS FROM FORMING. COULD SEE A FEW MID LEVEL CLOUDS IN
AND NEAR THE KCNU TAF SITE ALONG A WEAK MID LEVEL BAROCLINIC ZONE.
KETCHAM
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 72 98 75 98 / 10 0 0 0
HUTCHINSON 72 100 76 100 / 10 0 0 0
NEWTON 71 98 75 98 / 10 0 0 0
ELDORADO 71 97 74 97 / 10 0 0 0
WINFIELD-KWLD 73 98 75 98 / 20 0 0 0
RUSSELL 72 103 76 102 / 10 0 0 0
GREAT BEND 73 103 76 102 / 10 0 0 0
SALINA 72 99 76 101 / 10 0 0 0
MCPHERSON 72 99 76 100 / 10 0 0 0
COFFEYVILLE 71 96 72 95 / 10 0 0 0
CHANUTE 69 96 70 94 / 10 0 0 0
IOLA 68 96 70 94 / 0 0 0 0
PARSONS-KPPF 70 96 71 95 / 10 0 0 0
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
339 AM EDT FRI JUL 12 2013
.SYNOPSIS...
A COLD FRONT HAS BECOME STATIONARY ACROSS EASTERN VIRGINIA AND IS
PROVIDING THE FOCUS FOR HEAVY RAINFALL. THIS FRONT WILL REMAIN TO THE
SOUTHEAST OF THE AREA THROUGH SATURDAY. HIGH PRESSURE WILL BUILD
INTO THE REGION NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LAST NGT/S HRRR RUNS...NAM/GFS HAD THE SOLN NAILED. SHRA/TSRA FILLED
IN...WITH COPIOUS RAFL ACRS CWFA...SPCLY IN A STRIPE FM CENTRL SHEN
VLY INTO THE WRN BURBS OF DC. THAT ACTIVITY ONGOING ATTM...W/ NMRS
FLOOD CONCERNS. SYNOPICALLY...SVRL FACTORS CONTRIBUTING TO THE
SHRA-- FIRST...HGTS HV BEEN DROPPING AS AN H5 LOW APPROACHES FM THE
GRTLKS. SECONDLY...CWFA W/IN RRQ OF AN UPR JET. ITS ONLY ABT 70
KT...BUT IT/S SUFFICIENT TO SUPPORT LIFT. THIRD...A STALLED CDFNT
WAVERING ALONG THE I-95 CORRIDOR. BELIEVE THAT THERE ARE A CPL WK
IMPULSES GLIDING ALONG THE STALLED SFC BNDRY.
THESE INGREDIENTS WL STILL BE IN PLACE TDA. IN FACT HGTS WL BE QUITE
LOW AS H5 LOW COMES VERY CLOSE TO CWFA. IN ADDITION...ELY H8 WNDS WL
INCREASE...NOT JUST LEADING TO AN OVERRUNNING SITUATION BUT ALSO
PUMPING IN ADDITIONAL ATLC MSTR. PWAT WL BE HOVERING BTWN 1.75-2.00
INCHES FOR MOST OF THE DAY.
THE BIGGEST ADJUSTMENT IN GDNC FM THE 18Z TO 00Z CYCLES IS WHETHER
THERE WL BE A PRE-DAWN BREAK IN THE ACTION. NOT ONLY THE 00Z GDNC
CYCLE...BUT ALSO THE LTST HRRR AND RADAR TRENDS SUGGEST THAT WON/T
BE HAPPENING. FURTHER...THERE/S A STRONGER SIGNAL THAT THERE WL BE A
WK LOW MVG UP THE BAY TWD MIDDAY. THEREFORE...CANT DISCERN A PART OF
THE DAY THAT WL BE DRIER THAN THE REST. WL HV DECENT LLVL CNVGNC AND
ULVL DIVGNC THRUT. IF THERE/S ONE WRINKLE...ITS THE FACT THAT SNDGS
LOOK SO SATD THAT INSTBY WL BE MINIMAL.
CONSIDERING MSTR AND FORCING...AM CONCERNED THAT FLOODING WL BE A
CONCERN. FOR SOME SPOTS /SHD TO FFX/...IT WL BE AN ONGOING ISSUE...
WHILE IT WL BE A NEW CONCERN. THEREFORE...A FLOOD WATCH WL BE
APPROPRIATE. CONSIDERING HVY RAFL RATES...WIBIS A FLASH FLOOD WATCH
FOR MOST OF CWFA TIL WRN MTNS.
HV LKLY/CAT POPS FOR ALL AREAS XPCT THE PTMC HIGHLANDS. MAXT WL BE
KEPT DOWN...SPCLY FOR THE WEST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
DAYTIME ACTIVITY WL BE ONGOING INTO THE EVNG. HGTS WL START TO RISE
OVNGT. AM HOPEFUL THAT WL LEAD TO A LESSENING THREAT...AND WL TRAIL
POPS OFF OVNGT FM A PLATEAU OF LKLY. AS LONG AS THE SFC BNDRY
REMAINS...CANT COMFORTABLY REMOVE POPS FOR ANY PERIOD.
SAME BASIC CONCEPT EXTENDS INTO SAT. HGTS WL BE HIER AS H5 LOW
RETROGRADES IN RESPONSE TO BLDG RDG SFC-H5 FM WRN ATLC. HWVR...STILL
HV THE SAME FORCING MECHANISMS ON A HUMID AMS /PWATS DONT CHG TOO
MUCH/. WL HV POPS IN THE CHC CATEGORY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
AS HAS BEEN WRITTEN IN THE PAST TWO NGTS XTND DSCNS THE MDL
PROJECTED UPR LVL AND SFC PATTERNS FOR THE LATTER PARTS OF THE FCST
HV BEEN QUITE ANOMALOUS FOR MID JUL. REGARDLESS THE CONTINUITY BTWN
THE MDLS HAS BEEN GETTING GRTR SHOWING A SMALL UPR LVL CUTOFF LOW
OVR WEST VIRGINIA SAT TRACKING FURTHER WWD...AS HIGH PRES BUILDS OVR
NEW ENGLAND AND THEN INTO THE MID ATLC FOR MUCH OF THE NEW WK.
W/ SO MUCH MOISTURE OVR THE AREA IT IS PSBL THAT DIURNAL TSTMS
COULD DVLP SUN AFTN. AFTR THAT THE UPR RDG IS PROGGED TO COVER
MUCH OF THE ERN U.S. THRU AT LEAST MIDWEEK. TEMPS XPCTD TO CLIMB A
LTL EACH DAY...W/ HIGHS XPCTD TO GET BACK INTO THE 90S TUE THRU PSBLY
FRI. TYPICAL MID JUL WARMTH AT NGT W/ LOWS IN THE M70S IN THE
CITIES...60S W OF THE I-95.
THIS MAY NOT BE A LONG LIVED HEAT WV AS BOTH GFS AND ECMWF ARE
IMPLYING A WEAK TROF REDIGGING OVR QUEBEC/NEW ENGLAND BY NEXT FRI.
THIS WOULD LKLY BRING A CD FNT INTO THE NERN U.S. FRI. IF THIS
DOES OCCUR THE MID ALTC WL AGN HV CHCS FOR TSTMS.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
NRMS-WIDESPREAD SHRA/TSRA THIS MRNG. VSBY IMPACTS WL BE LCLZD...BUT
POTENTIALY AOB IFR. DUE TO DIFFICULTIES PINPOINTING SPECIFICS IN A
TAF STYLE FCST...HV KEPT VSBYS IN MVFR. CIGS...ON THE OTHER
HAND...SHUD BE LWRG. ON TOP OF MVFR CIGS EVERYWHERE...AM TAKING
STRONG GDNC SIGNALS OF IFR FOR CHO.
FRI WL BE AN UNSETTLED DAY OVERALL. AN UPR LOW WL ROTATE TWD
AREA...SUGGESTING THAT ANY BINOVC WL ONLY QUICKLY FILL BACK IN.
FURTHER...NLY SFC FLOW AND ELY FLOW JUST OFF THE SFC WL INHIBIT MUCH
DRYING W/IN THE COLUMN. DO NOT XPCT CIGS TO RISE MUCH TAFTN. FURTHER
TSRA WL ONLY REINFORCE POTL RESTRICTIONS. CONDS CUD REALLY DROP FRI
NGT AS RAFL EXITS BUT MOIST LLVL CONDS PREVAIL.
AFTN TSTMS PSBL AT ALL AIRPORTS SUN AFTN...THEN HIGH PRES XPCTD TO
BUILD IN DURG THE FIRST PART OF THE NEW WK.
&&
.MARINE...
STALLED CDFNT WL BE NEARBY...SO WINDS VRBL AOB 10 KT. HVY RAIN IS
THE PRIMARY THREAT...BUT LCLY HIER WNDS PRESENT W/IN THESE
DOWNPOURS. WIBIS SMW/S AS APPROPRIATE.
MAY BE ABLE TO NUDGE THE FNT EWD FRI. IF SO...THERE CUD BE A SMALL
SURGE IN WNDS. STILL DO NOT HV HIGH CONFIDENCE IN THAT SCENARIO ATTM.
CONCERNS ARE THAT AN APPROACHING UPR LOW AND RIPPLES W/IN SFC FLOW
WL SUPPORT MORE SHRA/TSRA INSTEAD. AM KEEPING ALL WINDS BLO SCA
LVLS. BUT...ADDTL SMW/S MAY BE REQD.
IN THE XNTD PART OF THE FCST AFTN TSTMS WL BE PSBL ON THE WATERS
SUNDAY. OTHERWISE WINDS XPCTD TO RMN BLO SCA VALUES.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...FLASH FLOOD WATCH THROUGH THIS EVENING FOR DCZ001.
MD...FLASH FLOOD WATCH THROUGH THIS EVENING FOR MDZ003>007-009>011-
013-014-016>018.
VA...FLASH FLOOD WATCH THROUGH THIS EVENING FOR VAZ025>031-036>040-
042-050>057-501-502.
WV...FLASH FLOOD WATCH THROUGH THIS EVENING FOR WVZ051>053.
MARINE...NONE.
&&
$$
SYNOPSIS...WOODY!
NEAR TERM...HTS
SHORT TERM...HTS
LONG TERM...WOODY!
AVIATION...HTS/WOODY!
MARINE...HTS/WOODY!
AREA FORECAST DISCUSSION
NWS HASTINGS NE
432 AM CDT FRI JUL 12 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 431 AM CDT FRI JUL 12 2013
THE PRIMARY ISSUE DURING THE NEXT 24 HOURS IS DETERMINING HOW HOT
WE ACTUALLY GET TODAY/HOW CLOSE WE GET TO HEAT ADVISORY
CRITERIA...AND HOW CLOSE TO CRITICAL FIRE DANGER WESTERN PARTS OF
NORTH CENTRAL KANSAS MIGHT GET. ALTHOUGH THE FORECAST PRODUCTS
CARRY NO MENTION OF SHOWERS/THUNDERSTORMS DUE TO POPS HOLDING BELOW
15 PERCENT...POPS ARE NOT NECESSARILY ZERO...AND WILL HAVE TO KEEP
AN EYE ESPECIALLY ON FAR WESTERN/NORTHERN COUNTIES LATE THIS
AFTERNOON-TONIGHT FOR THE REMOTE CHANCE THAT A FEW STORMS COULD
POP UP OR MOVE IN FROM THE WEST/NORTH. IN THE IMMEDIATE NEXT FEW
HOURS...ITS NOT COMPLETELY OUT OF THE QUESTION THAT A FEW HIGH-
BASED SHOWERS/STORMS COULD TRY DEVELOPING IN EASTERN ZONES BEFORE
SUNRISE.
08Z OBJECTIVE SURFACE ANALYSIS REVEALS A FAIRLY ILL-DEFINED QUASI-
STATIONARY FRONT SNAKING FROM A 1000 MILLIBAR LOW IN NORTHWEST
SD...SOUTHWARD THROUGH WESTERN NEBRASKA INTO NORTHWEST/SOUTH CENTRAL
KS. OFF TO THE EAST...A 1019MB HIGH IS CENTERED NEAR THE IA/IL
BORDER. BETWEEN THE FRONT AND THE HIGH...FAIRLY STEADY SOUTH-
SOUTHEAST BREEZES OF 8-15 MPH WITH OCCASIONAL GUSTS OVER 20 ARE IN
PLACE ACROSS THE CWA EARLY THIS MORNING...WITH THESE BREEZES
EXPECTED TO HELP HOLD LOW TEMPS UP BETWEEN 69-74 IN MOST AREAS.
ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA HIGHLIGHT A
FAIRLY EXPANSIVE MID/UPPER LEVEL RIDGE AXIS THAT HAS BUILT
NORTHEAST SINCE 24 HOURS AGO TO ENCOMPASS MUCH OF THE
CENTRAL/SOUTH CENTRAL CONUS. THE CENTER AXIS OF THIS RIDGE...AT
ROUGHLY 590 DECAMETER...RUNS FROM ROUGHLY THE LOCAL CWA ON THE
NORTHEAST EDGE...BACK SOUTHWESTWARD TOWARD THE NM/TX BORDER. WITH
THIS RIDGE AXIS NEARLY OVERHEAD...THE FLOW OVER THE CWA AT 500MB
IS FAIRLY LIGHT/VARIABLE...WHILE A BIT LOWER AT 700MB...THERE IS
MODEST WEST-SOUTHWEST FLOW. A NARROW ZONE OF THETA-E ADVECTION
ALONG A FAIRLY TIGHT 700MB MOISTURE GRADIENT HAS RESULTED IN A
SCATTERED ACCAS FIELD WITHIN ROUGHLY THE EASTERN 1/3 OF THE CWA
TONIGHT...AND RECENTLY THE FIRST FEW HINTS OF ISOLATED ELEVATED
SPRINKLES/LIGHT SHOWERS HAVE SHOWED UP ON RADAR WITHIN A FEW OF
OUR EASTERN COUNTIES.
STARTING WITH THE MOST IMMEDIATE ISSUE...WILL BE CLOSELY
MONITORING RADAR TRENDS IN EASTERN ZONES PRIOR TO SUNRISE TO SEE
WHETHER THE AFOREMENTIONED VERY ISOLATED CONVECTION CAN BE COVERED
WITH A SPRINKLE MENTION...OR MIGHT NEED SOMETHING MORE.
THE LATEST RAP HAS CAUGHT ONTO THIS DEVELOPMENT...AND SUGGESTS
THAT MAINLY OUR FAR EASTERN COUNTIES NEAR THE HWY 81 CORRIDOR
COULD CONTINUE TO SEE SOME OF THIS PRE-DAWN ACTIVITY...BUT THAT IT
SHOULD LARGELY BE DONE OR ADVECTED EAST OF THE CWA BY 7AM/12Z. PER
FORECAST SOUNDINGS...PARCELS ROOTED NEAR 700MB COULD POTENTIALLY
HAVE UP TO AROUND 400 J/KG MUCAPE AVAILABLE TO THEM...SO A BRIEF
FLARE UP OF NON-SEVERE THUNDERSTORMS IS NOT COMPLETELY OUT OF THE
QUESTION. FOR NOW...WILL ONLY MENTION ISOLATED SPRINKLES IN OUR
EASTERN FEW COLUMNS OF NEBRASKA COUNTIES THROUGH 12Z TO COVER
THINGS...PENDING ANY EVIDENCE OTHERWISE.
TURNING TO THE DAYTIME HOURS...THE MAIN STORY WILL BE A RETURN OF
LEGITIMATE SUMMER HEAT...BUT DOES NOT APPEAR TO BE HEADLINE-
WORTHY. IN THE MID/UPPER LEVELS...THE DOMINANT RIDGE AXIS WILL
CONTINUE TO EXPAND ACROSS THE CENTRAL PLAINS IN A SOUTHWEST-
NORTHEAST FASHION...WITH PARTS OF THE CWA ALIGNED ALMOST DIRECTLY
UNDER ITS CENTER AXIS. AT THE SURFACE...A FAIRLY SHARP TROUGH
AXIS WILL SET UP FROM FAR EASTERN CO ACROSS NORTHWEST NEB INTO
CENTRAL SD BY MID-LATE AFTERNOON...EXTENDING FROM A ROUGHLY 1000MB
LOW CENTERED NEAR THE CO/KS BORDER. THE LOCAL CWA WILL REMAIN IN
THE OPEN WARM SECTOR SOLIDLY SOUTHEAST OF THIS TROUGH AXIS...AND
THUS WILL SEE A CONTINUATION OF FAIRLY BREEZY SOUTH-SOUTHEAST
WINDS...WITH SUSTAINED SPEEDS MOST ALL AREAS 15-20 MPH AND GUSTS
25 TO POSSIBLY 30 MPH AT TIMES. AS FOR CONVECTIVE CHANCES...ASIDE
FROM ANY EARLY MORNING ACTIVITY IN THE EAST...THERE IS LITTLE IF
ANY RISK OF SHOWERS/STORMS TODAY AS WARM MID LEVEL TEMPS WITHIN
THE RIDGE AXIS SHOULD SERVE TO CAP THINGS OFF PRETTY SOLIDLY. ONE
OF THE ONLY POSSIBLE CAVEATS...AS DEPICTED BY THE LATEST RAP
RUNS...IS THAT STRONG HEATING AND VERY DEEP MIXING COULD POP A FEW
HIGH-BASED STORMS LATE IN THE AFTERNOON ALONG WESTERN PORTIONS OF
THE NEB/KS BORDER...WITH SOME OF THIS ACTIVITY POSSIBLY ADVECTING
EAST INTO THE DAWSON-FURNAS COUNTY CORRIDOR...BUT THE ODDS OF THIS
SEEM LOW ENOUGH TO STICK WITH SILENT 10 POPS FOR NOW...AS MOST
LATE AFTERNOON STORMS SHOULD FOCUS WELL TO OUR NORTHWEST ALONG THE
AFOREMENTIONED TROUGH AXIS. TEMP-WISE...BASED ON HOW HIGHS TURNED
OUT YESTERDAY...IT APPEARS THE NAM AND ASSOCIATED MET GUIDANCE HAS
BEEN A BIT AGGRESSIVE WITH THE HEAT...AND AS A RESULT...HAVE
SHAVED A FEW DEGREES OFF HIGHS TODAY IN MOST AREAS...USING VALUES
A BIT CLOSER TO GFS MAV GUIDANCE AND A MULTI-MODEL BLEND. THIS STILL
YIELDS A VERY TOASTY DAY WITH HIGHS RANGING FROM MID 90S NORTHEAST
...MID-UPPER 90S CENTRAL AND UPPER 90S TO AROUND 102 IN KS ZONES
AND NEAR THE STATE LINE. AS FOR DEWPOINTS...NOT EXPECTING A
DRAMATIC MIX-DOWN TODAY GIVEN THAT WINDS WILL BE MORE SOUTHERLY
VERSUS SOUTHWESTERLY...BUT NUDGED THEM DOWN A BIT ESPECIALLY IN
WESTERN ZONES...RANGING FROM UPPER 50S AT MID-AFTERNOON IN THE FAR
WEST TO MID-UPPER 60S IN THE EAST. THE RESULTANT HEAT INDEX VALUES
PEAK IN THE 98-100 RANGE ACROSS MOST OF THE NEB CWA...WITH KS
ZONES AND AREAS NEAR THE STATE LINE MORE LIKELY TO REACH THE
101-104 RANGE. BOTTOM LINE HERE IS...THESE VALUES ARE CERTAINLY
WORTH A HAZARDOUS WEATHER OUTLOOK MENTION...BUT DO NOT JUSTIFY A
FORMAL HEAT ADVISORY BASED ON OUR 105+ LOCAL CRITERIA. PLEASE NOTE
THAT THE NORTH PLATTE/LBF CWA HAS A SLIGHTLY COOLER
...CLIMATOLOGICALLY-BASED HEAT ADVISORY CRITERIA OF 100+...AND
THIS IS WHY A FORMAL HEADLINE IS OUT FOR THEIR AREA...BUT NOT FOR
OURS.
TURNING TO THIS EVENING/TONIGHT POST-7PM/00Z...THE MAIN STORY
VERSUS PREVIOUS FORECAST IS THAT THE SLIGHT CHANCE OF
THUNDERSTORMS HAS BEEN TRIMMED FROM THE EXTREME NORTHERN/WEST-
CENTRAL EDGES OF THE CWA...AND THUS WILL CARRY A STORM-FREE
FORECAST CWA-WIDE. AGAIN THOUGH...WILL EMPHASIZE THAT SILENT 10
POPS WILL REMAIN IN PLACE ESPECIALLY IN NORTHERN/WESTERN COUNTIES
TO AT LEAST ACKNOWLEDGE THAT A VERY LOW PROBABILITY OF SOME
ACTIVITY IS NOT COMPLETELY OUT OF THE QUESTION. IN THE MID-UPPER
LEVELS...THERE IS VERY LITTLE CHANGE WITH THE STRENGTH/ORIENTATION
OF THE EXPANSIVE RIDGE AXIS...AS IT REMAINS DRAPED FROM SOUTHWEST-
NORTHEAST ACROSS THE HEART OF THE CENTRAL PLAINS. A BIT LOWER AT
850MB...A 40+KT SOUTHERLY LOW LEVEL JET CRANKS UP THROUGH THE
NIGHT FROM WESTERN KS ACROSS CENTRAL NEB INTO EASTERN SD/WESTERN
MN...HELPING TO FOCUS THE VAST MAJORITY OF REGIONAL CONVECTION
NEAR THE EXIT REGION OF THIS FEATURE FROM NORTHEAST CO ACROSS
NORTHWEST NEB INTO SD/MN. AT THE SURFACE...THERE WILL ALSO BE
LITTLE OVERALL CHANGE FROM THE DAYTIME HOURS...WITH THE TROUGH
AXIS PERSISTING FROM NEAR THE KS/CO BORDER NORTH-NORTHEAST INTO
CENTRAL SD. WITH A CONTINUED MODEST PRESSURE GRADIENT AND LIMITED
MIXING UNDER THE LOW LEVEL JET...SURFACE BREEZES ACROSS THE CWA
WILL AGAIN AVERAGE 10-15 MPH FROM THE SOUTH-SOUTHEAST. ASSUMING
THAT POTENTIALLY ROGUE LATE AFTERNOON/EARLY EVENING STORMS DO NOT
AFFECT THE FAR WESTERN CWA...ITS PRETTY APPARENT FROM MOST MODEL
DEPICTIONS THAT OVERNIGHT CONVECTION SHOULD FOCUS AT LEAST 50-100
MILES NORTH THROUGH NORTHWEST OF THE CWA...AND GENERALLY LIFT
NORTH WITH TIME. THE ONLY FORESEEABLE CAVEAT HERE WOULD BE IF
NORTHERN NEB STORMS DEVELOP A COLD POOL AND START TO BUILD
SOUTHWARD INTO THE LOW LEVEL JET AXIS...POTENTIALLY REACHING THE
NORTHERN PARTS OF THE CWA. INTERESTINGLY...AT LEAST ONE
MODEL...THE 4KM WRF-NMM FROM PSU...DOES DEPICT THIS SCENARIO...BUT
GIVEN SUCH LIMITED SUPPORT WILL KEEP IT STORM-FREE FOR NOW. WILL
ALSO NOTE THAT THE 00Z GFS DEPICTION OF LATE NIGHT STORMS FLARING
UP NEAR HIGHWAY 81...LIKELY IN RESPONSE TO ANOTHER SUBTLE BATCH OF
MID LEVEL THETA-E ADVECTION...HAS BEEN DISREGARDED AS AN OUTLIER
AS WELL FOR THIS FORECAST. LOW TEMPERATURES WERE CHANGED
LITTLE...AND AGAIN REFLECT A SLIGHT UPWARD TREND FROM THE PAST FEW
NIGHTS...WITH MOST AREAS PROGGED TO BOTTOM OUT 72-75.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 431 AM CDT FRI JUL 12 2013
FOCUS FOR THIS TIMEFRAME WILL INVOLVE BOTH HIGH TEMPERATURES AND
PRECIPITATION CHANCES. MOST OF THE OPERATIONAL MODELS ARE COMING
INTO AGREEMENT ON THE UNUSUAL PATTERN EXPECTED IN THE SATURDAY TO
THURSDAY PERIOD. THEY ARE TAKING THE MID/UPPER LEVEL LOW PRESSURE
CURRENTLY SITTING OVER OHIO...AND RETROGRADING IT BACK TO THE
WEST. BY 12Z SAT THE GFS HAS IT OVER CENTRAL TENN...WHILE THE EC
PLACES IT A LITTLE NORTH OF THERE OVER KENTUCKY...AND THE NAM IS
BETWEEN THE TWO. BY 12Z SUNDAY THESE MODELS HAVE IT FROM CENTRAL
MISSOURI TO WESTERN ARKANSAS. THIS WESTWARD PUSH IS PROGGED TO
CONTINUE AND BY 12Z MONDAY IT IS FORECAST TO BE FROM NORTHERN
OKLAHOMA TO NORTHERN TEXAS. IT THEN APPEARS TO REMAIN OVER THE
TEXAS PANHANDLE OR IN NORTHEASTERN NEW MEXICO WHILE GRADUALLY
FILLING INTO THE WORKWEEK.
THIS IS NOT A VERY COMMON SCENARIO AND IF IT DOES COME TO FRUITION
WOULD MEAN COOLER TEMPERATURES STARTING SUNDAY. IN THE PAST 24
HRS...THE EXPECTED 850 MB TEMPS FOR SUNDAY OVER OUR AREA HAVE
DECREASED ABOUT 8-10 DEGREES C. GIVEN THE CONSISTENCY OF THE VARIOUS
OPERATIONAL MODELS WILL BUY INTO THIS SCENARIO AND LOWER HIGHS ON
SUNDAY BY SEVERAL DEGREES. SIMILAR TEMPERATURES CAN BE EXPECTED ON
MONDAY AND TUESDAY. WHILE COOLER THAN THOSE EXPECTED FOR TODAY AND
SATURDAY...WOULD NOT EXACTLY CALL IT COOL WEATHER AS HIGHS WILL
ACTUALLY BE AROUND NORMAL FOR THIS TIME OF YEAR FOR SUN-TUES. AFTER
THAT WE SHOULD SEE A GRADUAL WARMUP AS RIDGE RE-ESTABLISHES ITSELF
OVER THE REGION.
PRECIPITATION CONTINUES TO BE DIFFICULT TO FORECAST. LOOKS LIKE
THERE ARE AT LEAST SLIGHT CHANCES ON SAT AND SUNDAY NIGHTS OVER MUCH
OF THE CWA WITH A SURFACE BOUNDARY JUST TO OUR WEST...WEAK WAVES
ROTATING JUST TO OUR NORTH ALONG THE NORTHERN JET...AND THE
APPROACHING RETROGRADING LOW MENTIONED ABOVE. WILL CONTINUE TO
FORECAST DRY WEATHER FOR THE UPCOMING WORKWEEK BUT THAT MAY CHANGE
DEPENDING HOW FAR NORTH THAT RETROGRADING LOW TRACKS. AT
PRESENT...IT MAY AFFECT THE KANSAS PART OF OUR CWA BUT THE FURTHER
NORTH ITS TRACK...THE BETTER THE CHANCE FOR SOME RAIN IN THE NEB
PART OF OUR CWA.
&&
.AVIATION...(FOR THE 06Z KGRI TAF THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1259 AM CDT FRI JUL 12 2013
THERE IS FAIRLY HIGH CONFIDENCE THAT VFR CEILING/VISIBILITY WILL
PREVAIL THROUGH THE PERIOD...WITH MID/UPPER LEVEL HIGH PRESSURE
DOMINATING THE LOCAL WEATHER PATTERN AND PROVIDING MOSTLY CLEAR
SKIES...AND VERY LITTLE IF ANY RISK OF A SHOWER/THUNDERSTORM. AS
FOR SURFACE WINDS...A RATHER CONSTANT SOUTH-SOUTHEAST DIRECTION
WILL PREVAIL THROUGHOUT THE PERIOD...AND IT WILL REMAIN FAIRLY
BREEZY MOST OF THE TIME...WITH GUSTS COMMONLY UP TO AROUND
18KT...AND FRIDAY DAYTIME GUST POTENTIAL TO AT LEAST 25KT AT
TIMES. THE ONLY REAL ISSUE OF NOTE IS LOW LEVEL WIND SHEAR
UNDERNEATH A LOW LEVEL JET ALOFT. WILL CONTINUE A MENTION OF
SOMEWHAT MARGINAL LLWS THROUGH 14Z THIS MORNING...TO ACCOUNT FOR A
30+KT BULK SHEAR DIFFERENCE BETWEEN THE SURFACE AND APPROXIMATELY
1500 FT AGL...WHERE SUSTAINED SOUTHERLY WINDS UP TO AROUND 44KT
WILL RESIDE. ANOTHER ROUND OF LLWS COULD DEVELOP LATE FRIDAY
NIGHT...BUT THIS WILL MAINLY FALL WITHIN LATER FORECAST PERIODS.
&&
.FIRE WEATHER...
ISSUED AT 431 AM CDT FRI JUL 12 2013
ALTHOUGH CRITICAL FIRE WEATHER CONDITIONS/DANGER ARE NOT
ANTICIPATED WITHIN THE CWA TODAY...NEAR-CRITICAL CONDITIONS ARE
FORECAST ESPECIALLY IN THE FAR SOUTHWEST IN THE PHILLIPS/ROOKS
COUNTY AREAS...AND THUS WILL INTRODUCE THIS MENTION INTO THE
HAZARDOUS WEATHER OUTLOOK. THIS AREA WILL FEATURE THE GREATEST
OVERLAP OF SUSTAINED WINDS/GUSTS 20/25 MPH...AND RELATIVE HUMIDITY
VALUES NEAR OR SLIGHTLY BELOW 25 PERCENT. CERTAINLY...AT LEAST A
LIMITED FIRE DANGER WILL EXIST ELSEWHERE ACROSS THE CWA GIVEN THE
STEADY BREEZES AND OVERALL DRY CONDITIONS OF LATE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...PFANNKUCH
LONG TERM...EWALD
AVIATION...PFANNKUCH
FIRE WEATHER...PFANNKUCH
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
1137 PM MDT THU JUL 11 2013
.AVIATION...
06Z TAF CYCLE
MAIN UPPER HIGH CENTER TO SHIFT SLOWLY INTO THE CENTRAL HIGH
PLAINS NEXT 24 HOURS. OUTFLOW BOUNDARY FROM CONVECTION OVER THE
JEMEZ MTS HAS SPAWNED ADDITIONAL CONVECTION INTO THE MIDDLE
RGV...WHICH MAY PERSIST UNTIL AROUND D8Z. ISOLD BUT HEAVY RAIN
MAY RESULT IN LOCALIZED MVFR TO BRIEFLY IFR CIGS/VSBYS AND MT
OBSCURATIONS.
&&
.PREV DISCUSSION...1107 PM MDT THU JUL 11 2013...
MUCH OF THE CONVECTION HAS DIMINISHED THESE EVENING EXCEPT IN THE
VICINITY OF THE JEMEZ MOUNTAINS. AN OUTFLOW BOUNDARY ORIGINATING
FROM THESE STORMS HAS PUSHED OUTWARD TOWARD SANTA FE AND
ALBUQUERQUE. ADDITIONAL STORM DEVELOPMENT IS LIKELY ALONG THIS
BOUNDARY...AND THE LATEST HRRR SUPPORTS THIS WELL. THE NAM AND TO
SOME EXTENT THE HRRR...HAVE A BATCH OF STORMS MOVING UP INTO THE
SOUTHWEST MOUNTAINS LATE TONIGHT AS WELL. UPDATED POP GRIDS FOR
THE OVERNIGHT PERIOD. NO OTHER CHANGES MADE ATTM. UPDATES OUT
SHORTLY.
34
&&
.
&&
.PREV DISCUSSION...300 PM MDT THU JUL 11 2013...
WEAK SOUTHERLY LOW LEVEL FLOW WITH COPIOUS MOISTURE IN PLACE AS
EVIDENCED BY THE MORNING CLOUDINESS AND OVERNIGHT WEAK MCS THAT
PERSISTED INTO THE EARLY MORNING HOURS ACROSS EAST CENTRAL PLAINS
AND A 12Z KABQ PWAT VALUE AT 1.26 INCHES. EXPECT SLOW GENERALLY
SOUTH TO NORTH NORTHEAST STORM MOTIONS AND HEAVY PRECIPITATION
POTENTIALS ACROSS THE FORECAST AREA THIS AFTERNOON AND EVENING.
THE 592H5 UPPER HIGH IS DRIFTING NE TOWARDS THE TX-OK PANHANDLES
BY TOMORROW AFTERNOON. AS THE HIGH DRIFTS TO THE NE THIS WILL
GENERALLY ENHANCE OUR SOUTHERLY FLOW ESPECIALLY ACROSS THE WESTERN
MOUNTAINS. AS A RESULT THE FOCUS FOR STORMS AND PRECIPITATION WILL
SHIFT TOWARDS AREAS WEST OF THE RIO GRANDE AND ESPECIALLY THE
WESTERN MOUNTAINS OVER THE WEEKEND.
EARLY NEXT WEEK FORECAST CONFIDENCE IS LOW AT THIS TIME BECAUSE THE
LONG RANGE MODELS ARE HAVING A DIFFICULT TIME WITH A HIGHLY UNUSUAL
PATTERN OF AN UPPER LOW RETROGRADING FROM THE OHIO RIVER VALLEY
TOWARDS TX PANHANDLE BY MONDAY AFTERNOON AS A VERY STRONG 598H5
UPPER HIGH BUILDS OVER OHIO-INDIANA. AN UPPER LOW WOULD BRING
ADDITIONAL INSTABILITY AND MOISTURE TO OUR FORECAST AREA CAUSING
PRECIPITATION CHANCES TO INCREASE FOR NEXT WEEK. WILL HAVE AWAIT
MORE IMPROVED MODEL CONSENSUS OR BETTER RUN-TO-RUN CONSISTENCY TO
PROVIDE MORE PRECISE FORECAST DETAILS. FOR NOW...FOR THE EARLY TO
MIDDLE OF NEXT WEEK...EXPECT SEASONAL POPS AROUND 10 TO 30 PERCENT
WITH STORMS INITIATING OVER HIGHER TERRAIN EARLY THEN AFFECTING
PLAINS AND VALLEYS BY LATE AFTERNOON AND EVENING. IF THIS UPPER LOW
AFFECTS THE AREA POPS WILL INCREASE.
BENNETT
&&
.FIRE WEATHER...
CONVECTION HAS BEEN A BIT SLOWER TO START TODAY DUE TO LINGERING MID
LEVEL CLOUDS FROM THE OVERNIGHT CONVECTION. NONETHELESS...SHOWERS
AND THUNDERSTORMS WILL CONTINUE TO DEVELOP THIS AFTERNOON AND
EVENING AS INSTABILITY INCREASES WITH DAYTIME HEATING. SHOWERS AND
STORMS WILL FAVOR AREAS ALONG AND WEST OF THE CENTRAL MOUNTAIN
CHAIN. PRECIPITABLE WATER VALUES EARLY THIS AFTERNOON PER SATELLITE
IMAGERY CONTINUE TO SHOW ABOVE NORMAL VALUES FOR MID JULY...THUS
HEAVY RAINFALL IS POSSIBLE JUST ABOUT ANYWHERE. FORTUNATELY...STORMS
ARE MOVING A BIT FASTER THAN IN RECENT DAYS...WHICH WILL HELP
MITIGATE EXCESSIVE RAINFALL TOTALS.
ON FRIDAY...THE UPPER HIGH ELONGATES NORTHEASTWARD...WITH THE CENTER
OF THE HIGH OVER KANSAS. THOUGH THE RIDGE AXIS EXTENDS BACK INTO SC
NM...THERE SHOULD BE SOME CONTINUED MONSOONAL MOISTURE TRANSPORT
INTO CENTRAL AND WESTERN NM. THUS...EXPECT IT TO REMAIN ACTIVE OVER
THE HIGH TERRAIN...WITH STEERING FLOW SIMILAR TO...OR SLIGHTLY LESS
THAN...TODAY.
THE UPPER LEVEL HIGH WILL BUILD BACK TO THE WEST ON SATURDAY...AND
AN AREA OF DRIER AIR/SUBSIDENCE WILL MOVE INTO THE SOUTHEAST HALF OR
SO OF THE FORECAST AREA. CONVECTIVE COVERAGE WILL BE DOWN
OVERALL...BUT SCATTERED STORMS WILL REMAIN POSSIBLE ACROSS THE
NORTHERN MOUNTAINS AND WESTERN HIGH TERRAIN. STEERING FLOW WILL BE
LIGHTER...THUS EXPECT SLOWER STORM MOTIONS.
THE UPPER HIGH WILL CONTINUE TO BUILD WESTWARD ON SUNDAY...OVER
NORTH CENTRAL NM...AND THE AREA OF DRY AIR WILL CONTINUE TO MOVE
WESTWARD AS WELL. THIS COMBINATION WILL LIMIT CONVECTION FURTHER.
OTHERWISE...LITTLE DAY TO DAY CHANGE WITH HUMIDITIES ARE
EXPECTED...THOUGH SUNDAY WILL BE THE DRIEST DAY OVERALL. AN AREA OF
POOR TO FAIR VENTILATION IS EXPECTED ON FRIDAY FROM THE WEST CENTRAL
HIGHLANDS NORTHEAST TO THE NORTHERN MTNS...THOUGH GOOD TO EXCELLENT
VENTILATION IS EXPECTED ELSEWHERE. ON SATURDAY...POOR TO FAIR
VENTILATION WILL FAVOR THE NORTHWEST QUARTER OF THE STATE.
HOWEVER...BY SUNDAY...GOOD VENTILATION OR BETTER IS EXPECTED ACROSS
MOST AREAS AS MIXING HEIGHTS INCREASE.
THE MODELS CONTINUE TO STRUGGLE WITH THE EARLY WEEK PATTERN. LATEST
RUNS HAVE THE HIGH RETREATING FURTHER WESTWARD AS AN EASTERLY WAVE
SLOWLY SLIDES INTO NORTHEAST NM. IF THIS OCCURS...MUCH OF NEXT WEEK
COULD BE WET. HOWEVER...GIVEN THAT THIS IS A HIGHLY UNUSUAL
PATTERN...AND MODELS ARE WAFFLING A BIT...CONFIDENCE IS MODERATE TO
LOW ON THIS SCENARIO.
34
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1107 PM MDT THU JUL 11 2013
.UPDATE...
MUCH OF THE CONVECTION HAS DIMINISHED THESE EVENING EXCEPT IN THE
VICINITY OF THE JEMEZ MOUNTAINS. AN OUTFLOW BOUNDARY ORIGINATING
FROM THESE STORMS HAS PUSHED OUTWARD TOWARD SANTA FE AND
ALBUQUERQUE. ADDITIONAL STORM DEVELOPMENT IS LIKELY ALONG THIS
BOUNDARY...AND THE LATEST HRRR SUPPORTS THIS WELL. THE NAM AND TO
SOME EXTENT THE HRRR...HAVE A BATCH OF STORMS MOVING UP INTO THE
SOUTHWEST MOUNTAINS LATE TONIGHT AS WELL. UPDATED POP GRIDS FOR
THE OVERNIGHT PERIOD. NO OTHER CHANGES MADE ATTM. UPDATES OUT
SHORTLY.
34
&&
.PREV DISCUSSION...542 PM MDT THU JUL 11 2013...
.AVIATION...
00Z TAF CYCLE
WITH THE UPPER HIGH CENTERED MORE OR LESS OVER NORTHEAST NEW
MEXICO...STEERING FLOWS WILL REMAIN RELATIVELY LIGHT...WITH CELLS
MOVING TO THE NORTH AND NORTHWEST OVER WRN NM AND MORE ERRATIC
MOVEMENT ELSEWHERE. ATMOSPHERIC MOISTURE IS HIGH AND SHOWERS AND
STORMS COULD PRODUCE LOCALLY HEAVY RAIN RESULTING IN MVFR TO
BRIEFLY IFR CIGS/VSBYS AND MT OBSCURATIONS. GUSTY OUTFLOWS OF 35KT
TO 40KT ARE EXPECTED AS WELL. CONVECTION TO SLOWLY DIMINISH
BETWEEN 06Z TO 09Z ALTHOUGH LINGERING SHRA ARE POSSIBLE.
300 PM MDT THU JUL 11 2013...
WEAK SOUTHERLY LOW LEVEL FLOW WITH COPIOUS MOISTURE IN PLACE AS
EVIDENCED BY THE MORNING CLOUDINESS AND OVERNIGHT WEAK MCS THAT
PERSISTED INTO THE EARLY MORNING HOURS ACROSS EAST CENTRAL PLAINS
AND A 12Z KABQ PWAT VALUE AT 1.26 INCHES. EXPECT SLOW GENERALLY
SOUTH TO NORTH NORTHEAST STORM MOTIONS AND HEAVY PRECIPITATION
POTENTIALS ACROSS THE FORECAST AREA THIS AFTERNOON AND EVENING.
THE 592H5 UPPER HIGH IS DRIFTING NE TOWARDS THE TX-OK PANHANDLES
BY TOMORROW AFTERNOON. AS THE HIGH DRIFTS TO THE NE THIS WILL
GENERALLY ENHANCE OUR SOUTHERLY FLOW ESPECIALLY ACROSS THE WESTERN
MOUNTAINS. AS A RESULT THE FOCUS FOR STORMS AND PRECIPITATION WILL
SHIFT TOWARDS AREAS WEST OF THE RIO GRANDE AND ESPECIALLY THE
WESTERN MOUNTAINS OVER THE WEEKEND.
EARLY NEXT WEEK FORECAST CONFIDENCE IS LOW AT THIS TIME BECAUSE THE
LONG RANGE MODELS ARE HAVING A DIFFICULT TIME WITH A HIGHLY UNUSUAL
PATTERN OF AN UPPER LOW RETROGRADING FROM THE OHIO RIVER VALLEY
TOWARDS TX PANHANDLE BY MONDAY AFTERNOON AS A VERY STRONG 598H5
UPPER HIGH BUILDS OVER OHIO-INDIANA. AN UPPER LOW WOULD BRING
ADDITIONAL INSTABILITY AND MOISTURE TO OUR FORECAST AREA CAUSING
PRECIPITATION CHANCES TO INCREASE FOR NEXT WEEK. WILL HAVE AWAIT
MORE IMPROVED MODEL CONSENSUS OR BETTER RUN-TO-RUN CONSISTENCY TO
PROVIDE MORE PRECISE FORECAST DETAILS. FOR NOW...FOR THE EARLY TO
MIDDLE OF NEXT WEEK...EXPECT SEASONAL POPS AROUND 10 TO 30 PERCENT
WITH STORMS INITIATING OVER HIGHER TERRAIN EARLY THEN AFFECTING
PLAINS AND VALLEYS BY LATE AFTERNOON AND EVENING. IF THIS UPPER LOW
AFFECTS THE AREA POPS WILL INCREASE.
BENNETT
.FIRE WEATHER...
CONVECTION HAS BEEN A BIT SLOWER TO START TODAY DUE TO LINGERING MID
LEVEL CLOUDS FROM THE OVERNIGHT CONVECTION. NONETHELESS...SHOWERS
AND THUNDERSTORMS WILL CONTINUE TO DEVELOP THIS AFTERNOON AND
EVENING AS INSTABILITY INCREASES WITH DAYTIME HEATING. SHOWERS AND
STORMS WILL FAVOR AREAS ALONG AND WEST OF THE CENTRAL MOUNTAIN
CHAIN. PRECIPITABLE WATER VALUES EARLY THIS AFTERNOON PER SATELLITE
IMAGERY CONTINUE TO SHOW ABOVE NORMAL VALUES FOR MID JULY...THUS
HEAVY RAINFALL IS POSSIBLE JUST ABOUT ANYWHERE. FORTUNATELY...STORMS
ARE MOVING A BIT FASTER THAN IN RECENT DAYS...WHICH WILL HELP
MITIGATE EXCESSIVE RAINFALL TOTALS.
ON FRIDAY...THE UPPER HIGH ELONGATES NORTHEASTWARD...WITH THE CENTER
OF THE HIGH OVER KANSAS. THOUGH THE RIDGE AXIS EXTENDS BACK INTO SC
NM...THERE SHOULD BE SOME CONTINUED MONSOONAL MOISTURE TRANSPORT
INTO CENTRAL AND WESTERN NM. THUS...EXPECT IT TO REMAIN ACTIVE OVER
THE HIGH TERRAIN...WITH STEERING FLOW SIMILAR TO...OR SLIGHTLY LESS
THAN...TODAY.
THE UPPER LEVEL HIGH WILL BUILD BACK TO THE WEST ON SATURDAY...AND
AN AREA OF DRIER AIR/SUBSIDENCE WILL MOVE INTO THE SOUTHEAST HALF OR
SO OF THE FORECAST AREA. CONVECTIVE COVERAGE WILL BE DOWN
OVERALL...BUT SCATTERED STORMS WILL REMAIN POSSIBLE ACROSS THE
NORTHERN MOUNTAINS AND WESTERN HIGH TERRAIN. STEERING FLOW WILL BE
LIGHTER...THUS EXPECT SLOWER STORM MOTIONS.
THE UPPER HIGH WILL CONTINUE TO BUILD WESTWARD ON SUNDAY...OVER
NORTH CENTRAL NM...AND THE AREA OF DRY AIR WILL CONTINUE TO MOVE
WESTWARD AS WELL. THIS COMBINATION WILL LIMIT CONVECTION FURTHER.
OTHERWISE...LITTLE DAY TO DAY CHANGE WITH HUMIDITIES ARE
EXPECTED...THOUGH SUNDAY WILL BE THE DRIEST DAY OVERALL. AN AREA OF
POOR TO FAIR VENTILATION IS EXPECTED ON FRIDAY FROM THE WEST CENTRAL
HIGHLANDS NORTHEAST TO THE NORTHERN MTNS...THOUGH GOOD TO EXCELLENT
VENTILATION IS EXPECTED ELSEWHERE. ON SATURDAY...POOR TO FAIR
VENTILATION WILL FAVOR THE NORTHWEST QUARTER OF THE STATE.
HOWEVER...BY SUNDAY...GOOD VENTILATION OR BETTER IS EXPECTED ACROSS
MOST AREAS AS MIXING HEIGHTS INCREASE.
THE MODELS CONTINUE TO STRUGGLE WITH THE EARLY WEEK PATTERN. LATEST
RUNS HAVE THE HIGH RETREATING FURTHER WESTWARD AS AN EASTERLY WAVE
SLOWLY SLIDES INTO NORTHEAST NM. IF THIS OCCURS...MUCH OF NEXT WEEK
COULD BE WET. HOWEVER...GIVEN THAT THIS IS A HIGHLY UNUSUAL
PATTERN...AND MODELS ARE WAFFLING A BIT...CONFIDENCE IS MODERATE TO
LOW ON THIS SCENARIO.
34
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
410 AM CDT FRI JUL 12 2013
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 355 AM CDT FRI JUL 12 2013
FORECAST CHALLENGE WILL BE THE EXTENT AND DURATION OF SHOWERS AND
THUNDERSTORMS THROUGH THIS MORNING... THEN TIMING OF REDEVELOPMENT
LATER TODAY AND TONIGHT.
FOR NOW... LOW LEVEL MOISTURE TRANSPORT APPEARS TO HAVE SURGED IN
THE LAST COUPLE OF HOURS LEADING TO INCREASED DEEP CONVECTION ACROSS
NCNTRL AND FAR NERN ND... AHEAD OF A WEAK SFC COLD FRONT. THIS
AREA SHOWS 1500-2000 J/KG OF CAPE AND PWATS IN EXCESS OF 1.5
INCHES AT 08Z ANALYSIS... WITH 40KM RAP AND NAM GUIDANCE LIFTING
THIS AREA THROUGH FAR NERN ND INTO SRN MAN THROHGH 15Z. EXPECT
SOME BREAK IN THE ACTIVITY THROUGH MIDDAY WITH SERN ND AND WCNTRL
MN LIKELY TO HEAT OUT QUICKLY AND REACH CONVECTIVE TEMPS BY
MIDAFTERNOON.
NAM DEPICTION SEEMS REASONABLE THROUGH TODAY AND INTO THE EARLY
PORTION OF THE WEEKEND... SHOWING THE SFC FRONT SLOWLY SAGGING
INTO THE SOUTHERN FA BY TONIGHT AND STALLING THERE THROUGH SUNDAY
MORNING. LATE THIS AFTERNOON INTO EARLY SATURDAY MORNING EXPECT
THE FOCUS FOR DEEP CONVECTION TO SHIFT ACROSS THE SOUTHERN FA...
WITH PERIODS OF STRONG TO SEVERE THUNDERSTORMS POSSIBLE ALONG WITH
BRIEF HEAVY RAINS. CONVECTIVE INHIBITION SHUD BREAK DOWN FAIRLY
QUICKLY THROUGH MID AFTERNOON AS COOLER H7 TEMPS MOVE OVHD... WITH
SOME THREAT FOR ISOLD TORNADIC SUPERCELLS TO DEVELOP IN THE LATE
AFTERNOON...THROUGH CENTRAL PORTIONS OF THE RRV.
OVERNIGHT TONIGHT THROUGH SATURDAY... FOCUS WILL SWITCH TO HEAVIER
RAIN PRODUCING CONVECTIVE CLUSTERS ACROSS THE SOUTHERN HALF OF THE
THE RRV.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
SATURDAY NIGHT THROUGH SUNDAY... SOME BREAK IN THE THUNDERSTORM
ACTIVITY IS EXPECTED TO DEVELOP FROM NORTHWEST TO SOUTHEAST ON
SATURDAY. DEEP MOIST AND UNSTABLE FLOW SHUD RETURN TO TEH AREA ON
SUNDAY.
MONDAY THROUGH THURSDAY... LONG WAVE UPPER LEVEL RIDGE REMAINS
PARKED OVER CO THIS PERIOD. LONG WAVE TROUGH OVER WESTERN CANADA
SWEEPS INTO EASTERN CANADA BY THE END OF THE PERIOD. FLOW ALOFT
BECOMES NORTHWEST ALOFT OVER CANADA AND THE FAR NORTHERN PLAINS. A
FRONTAL BOUNDARY MOVES INTO THE AREA TUE OR WED. WILL BLEND THE
ECMWF AND GFS.
NORTHWEST FLOW ALOFT BECOMES ESTABLISHED OVER CANADA AND THE
NORTHERN STATES THIS PERIOD. GFS AND ECMWF WERE VACILLATING OVER
SOUTHERN CANADA AND FAR NORTHERN ZONES TUE. SO WILL REMOVE
PRECIPITATION FROM TUE AND TRIM BACK TUE NIGHT PRECIP FARTHER NORTH.
WILL KEEP YESTERDAYS POPS FOR WED NIGHT.
HIGH TEMPS INCREASED COUPLE DEGREES IN THE NORTHWEST ZONES TUE FROM
YESTERDAYS RUN. BOTH HIGH AND LOW TEMPS DECREASED ABOUT A DEGREE OR
TWO FOR WED AND THU.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1115 PM CDT THU JUL 11 2013
THE CHANCES FOR SHOWERS AND STORMS WILL INCREASE FROM WEST TO EAST
THROUGH TOMORROW. EXPECT MAINLY VFR CONDITIONS THOUGH WITH HIGH
CLOUD BASES WITH WARM AIR ALOFT. THERE COULD BE SOME POCKETS OF
MVFR CONDITIONS NEAR STRONGER STORMS AND DOWNPOURS...BUT WILL NOT
MENTION AT THIS POINT.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...GUST
LONG TERM...HOPPES
AVIATION...DK
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1145 PM CDT THU JUL 11 2013
.AVIATION...
VFR CONDITIONS PREVAILING FOR THE NEXT 24 HOURS AS UPPER LEVEL
HIGH PRESSURE CENTERED OVER THE SRN ROCKIES KEEPS S TX UNDER
GENERAL SUBSIDENCE. OTHERWISE S-SELY SFC WINDS AT 5-10 KNOTS
PREVAILING.
&&
.PREV DISCUSSION... /ISSUED 1000 PM CDT THU JUL 11 2013/
UPDATE...
MOST SHOWERS AND THUNDERSTORMS OVER EASTERN AND CENTRAL TEXAS HAVE
COME TO AN END THIS EVENING WITH ONLY SOME LINGERING SHOWERS TO
THE NORTH OF THE HILL COUNTRY. THE ONLY THING LEFT FROM THESE
EARLIER STORMS IS AN OUTFLOW BOUNDARY ENTERING THE NORTHEAST PART
OF WILLIAMSON COUNTY. THIS BOUNDARY WILL BRING A SLIGHTLY WIND
SHIFT ACROSS PARTS OF THE NORTHEAST HILL COUNTRY FOR A SHORT
PERIOD OF TIME WITH WIND GUSTS UP TO 20 MPH. CURRENT FORECAST IS ON
TRACK FOR THE REST OF THIS EVENING INTO FRIDAY MORNING.
PREV DISCUSSION... /ISSUED 707 PM CDT THU JUL 11 2013/
UPDATE...
INCREASED CLOUD COVERAGE THIS EVENING INTO THE OVERNIGHT HOURS AS
MID TO UPPER MOISTURE ASSOCIATED WITH A GROUP OF STORMS OVER EAST
TEXAS MOVE TO THE SOUTHWEST. HI-RES MODELS AND LATEST RAP SOLUTION
SHOWS STORMS SCATTERING OUT BEFORE ARRIVING TO THE NORTHEAST PART OF
THE HILL COUNTRY. WILL MONITOR CLOSELY THESE STORMS AS THEY
APPROACH THE LOCAL AREA FOR THE NEXT FEW HOURS AND ADJUST WEATHER
GRIDS IF NECESSARY. UPDATED ZONES OUT SHORTLY.
PREV DISCUSSION... /ISSUED 623 PM CDT THU JUL 11 2013/
AVIATION...
VFR CONDITIONS PREVAILING FOR THE NEXT 24 HOURS AS UPPER LEVEL
HIGH PRESSURE CENTERED OVER THE SRN ROCKIES KEEPS S TX UNDER
GENERAL SUBSIDENCE. WEAK DISTURBANCES ROTATING AROUND THE UPPER
RIDGE WILL MAINLY AFFECT THE N TX AREA WITH ISOLD-SCT AFTERNOON
AND EVENING SHRA/TSRA THAT SHOULD REMAIN NORTH OF THE S CENTRAL
TX. OTHERWISE S-SELY SFC WINDS AT 5-10 KNOTS PREVAILING.
PREV DISCUSSION... /ISSUED 331 PM CDT THU JUL 11 2013/
SHORT TERM (TONIGHT THROUGH FRIDAY NIGHT)...
THE SUBTROPICAL RIDGE AXIS REMAINS THE DOMINANT WEATHER FEATURE
THROUGH THE SHORT TERM PORTION OF THE FORECAST. GIVEN THE INFLUENCE
FROM THIS RIDGE...WE EXPECT A CONTINUATION OF DRY WEATHER ACROSS
SOUTH CENTRAL TEXAS. THE SHORT RANGE MODELS DO SHOW SOME CONVECTION
CONTINUING ACROSS NORTH TEXAS THIS EVENING...WITH SOME ACTIVITY
DRIFTING INTO CENTRAL TEXAS LATE TONIGHT INTO EARLY FRIDAY
MORNING. WE HAVE LOW CONFIDENCE THIS CONVECTION WILL BE ABLE TO
MOVE INTO OUR REGION...SO WE WILL CONTINUE WITH A DRY FORECAST.
HIGH TEMPERATURES REMAIN ABOVE NORMAL ON FRIDAY AND WILL RANGE
FROM THE MID/UPPER 90S IN THE HILL COUNTRY...WITH UPPER 90S TO
100-103 FOR THE REMAINDER OF THE REGION. OVERNIGHT LOWS WILL
REMAIN IN THE 70S.
LONG TERM (SATURDAY THROUGH THURSDAY)...
A BROAD SUBTROPICAL RIDGE WILL ENCOMPASS MUCH OF THE CENTRAL CONUS
THROUGH THE FIRST HALF OF THE UPCOMING WEEKEND. DRY CONDITIONS AND
ABOVE NORMAL TEMPERATURES WILL CONTINUE FOR ALL AREAS ON SATURDAY.
BASED ON THE LATEST MODEL DATA...IT APPEARS SATURDAY WILL BE THE
WARMEST DAY OF THE FORECAST PERIOD...WITH HIGHS GENERALLY IN THE
UPPER 90S TO NEAR 104. MODEL DATA FROM THE LAST SEVERAL DAYS WERE
CONSISTENT IN SHOWING A TUTT LOW MOVE ACROSS THE REGION LATE THIS
WEEKEND INTO EARLY NEXT WEEK. THE LATEST GUIDANCE DOES CONTINUE TO
SHOW A WEAK TUTT LOW...BUT ALSO SHOW A LOW DEVELOPING OVER THE UPPER
MIDWEST BY LATE FRIDAY. THE MODELS THEN RETROGRADE THIS LOW
SOUTHWEST INTO THE SOUTHERN U.S. PLAINS BY EARLY NEXT WEEK.
OVERALL... WE ARE NOT TOO CONFIDENT IN RAIN CHANCES INTO EARLY NEXT
WEEK. FOR NOW... WE WILL MAINTAIN THE CURRENT FORECAST WHICH
GENERALLY CALLS FOR A SLIGHT CHANCE (20%) OF RAIN FOR MOST AREAS
SUNDAY NIGHT THROUGH TUESDAY NIGHT. THROUGH THE REMAINDER OF THE
FORECAST PERIOD...WE WILL GO WITH A DRY FORECAST...EXCEPT NEAR THE
COASTAL PLAINS WHERE AFTERNOON/EVENING SEA BREEZE CONVECTION REMAINS
POSSIBLE. AS MENTIONED ABOVE...TEMPERATURES WILL PEAK ON SATURDAY...
THEN VERY SLOWLY MODERATE SUNDAY THROUGH THURSDAY. IT APPEARS A
BREAK FROM TRIPLE DIGIT HIGHS IS IN STORE...BUT TEMPERATURES WILL
CONTINUE TO REMAIN ABOVE NORMAL.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 75 103 75 104 76 / - - - - -
AUSTIN BERGSTROM INTL AIRPORT 72 101 72 102 72 / - - - - -
NEW BRAUNFELS MUNI AIRPORT 71 100 72 101 72 / - - - - -
BURNET MUNI AIRPORT 74 101 76 101 74 / 10 - - - -
DEL RIO INTL AIRPORT 77 101 77 103 77 / - - - - -
GEORGETOWN MUNI AIRPORT 74 101 74 101 74 / 10 - - - -
HONDO MUNI AIRPORT 74 101 74 102 73 / - - - - -
SAN MARCOS MUNI AIRPORT 72 100 72 101 72 / - - - - -
LA GRANGE - FAYETTE REGIONAL 76 102 76 101 77 / - 10 10 10 10
SAN ANTONIO INTL AIRPORT 77 101 77 101 77 / - - - - -
STINSON MUNI AIRPORT 75 101 75 101 75 / - - - - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...01
SYNOPTIC/GRIDS...17
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
840 AM MST FRI JUL 12 2013
.SYNOPSIS...
MOIST MONSOON AIR UNDER FAVORABLE SOUTHERLY FLOW WILL CONTINUE INTO
THE WEEKEND...BUT SOME DRIER AIR WILL BEGIN TO SLIDE EASTWARD INTO
SOUTHWEST ARIZONA BY SUNDAY. CHANCES OF SHOWERS AND THUNDERSTORMS
CONTINUE...BUT WILL GRADUALLY DECREASE ACROSS THE LOWER DESERTS THIS
WEEKEND. THE COOLER TEMPERATURES WILL LAST FOR ANOTHER DAY OR TWO
BEFORE WARMING TO NEAR NORMAL FOR THIS WEEKEND INTO EARLY NEXT WEEK.
&&
.DISCUSSION...
A RATHER QUIET MORNING SO FAR ACROSS THE REGION. LATEST RADAR
IMAGERY IS ONLY SHOWING A FEW SHOWERS AND THUNDERSTORMS MOVING INTO
SOUTHWEST MARICOPA COUNTY...IN THE VICINITY OF GILA BEND...AND A FEW
SHOWERS OVER JOSHUA TREE NATIONAL PARK. A NEW CLUSTER OF
THUNDERSTORMS IS NOW SEEN ON SATELLITE IMAGERY TRYING TO MOVE
NORTHWARD ACROSS THE INTERNATIONAL BORDER INTO EXTREME SOUTHERN
PIMA COUNTY. THE LATEST (13Z) HRRR MODEL RUN WEAKENS THIS NEW
THUNDERSTORM COMPLEX AS IT CONTINUES TO MOVE IT NORTHWARD INTO
SOUTHERN PINAL COUNTY LATE THIS AFTERNOON...THEN BASICALLY
DISSIPATES IT THIS EVENING BEFORE IT REACHES OUR CWA. THIS MODEL
ALSO DEVELOPS SOME SHOWER ACTIVITY OVER GILA COUNTY BETWEEN NOW AND
20Z...THEN SLOWLY WEAKENS THIS ACTIVITY THEREAFTER INTO THE LATE
AFTERNOON AND EVENING HOURS. OTHER THAN SOME MINOR CHANGES IN THE
TEMPERATURE...DEWPOINT...AND POP GRIDS TO REFLECT CURRENT
TRENDS...THE LATEST GRIDDED FORECASTS STILL LOOK GOOD.
&&
.PREVIOUS DISCUSSION...
FOR HAVING SUCH A MOIST AIRMASS IN PLACE ACROSS THE REGION...THE
AMOUNT OF MONSOON ACTIVITY YESTERDAY WAS SOMEWHAT LACKING. THE
EXTENSIVE CLOUDINESS...THE LACK OF ANY FOCUS MECHANISM...AND GENERAL
CONFLUENT FLOW ALOFT ALL LED TO A FAIRLY QUIET MONSOON DAY ACROSS
THE CWA. CURRENT RADAR TRENDS DO SHOW A SMALL CLUSTER OF SHOWERS AND
THUNDERSTORMS MOVING NORTHWESTWARD INTO FAR SOUTHEAST ARIZONA.
HI-RES MODEL REFLECTIVITY INDICATES THIS CLUSTER SHOULD MAKE IT INTO
GILA COUNTY AT AROUND SUNRISE...BUT AT THE SAME TIME BE WEAKENING
CONSIDERABLY. THE REST OF THE AREA...SHOULD STAY DRY THROUGH THE
REST OF THE MORNING HOURS.
TODAY AND SATURDAY ARE EXPECTED TO BE LOW-GRADE MONSOON DAYS EVEN
THOUGH THERE IS AMPLE MONSOON MOISTURE ACROSS THE ENTIRE REGION.
SIMILAR TO YESTERDAY...DAYTIME HEATING WILL BE SOMEWHAT LIMITED DUE
TO THE VERY MOIST SOUNDING PROFILES AND THE EXPECTED CLOUD COVER. WE
SHOULD SEE A BIT MORE THUNDERSTORM ACTIVITY THIS AFTERNOON INTO
TONIGHT...INITIALLY FOCUSED ACROSS THE HIGHER TERRAIN ACROSS EASTERN
ARIZONA AND THEN POSSIBLY TRANSITIONING INTO THE LOWER DESERTS.
CAN/T COMPLETELY RULE OUT SOME STRAY SHOWERS AND THUNDERSTORMS
ANYWHERE ACROSS THE CWA TODAY DUE TO THE WIDESPREAD MOIST
CONDITIONS...BUT THE LACK OF ANY DIVERGENCE ALOFT SHOULD KEEP
DEVELOPMENT ISOLATED. THE MAIN THREAT TODAY WILL BE VERY HEAVY
DOWNPOURS AND A SLIGHT POSSIBILITY OF LOCALIZED FLASH FLOODING. THE
OVERALL WIND THREAT REMAINS LOW DUE TO THE MOIST ATMOSPHERIC
PROFILES.
BY SATURDAY...MODELS INDICATE DRYING WILL START TO WORK INTO
SOUTHEAST CALIFORNIA AND FAR SOUTHWEST ARIZONA VIRTUALLY ELIMINATING
RAIN CHANCES THERE. MAINLY SLIGHT CHANCES FOR AFTERNOON AND EVENING
SHOWERS AND THUNDERSTORMS ARE EXPECTED ACROSS THE SOUTH-CENTRAL
DESERTS AND HIGHER CHANCES ACROSS THE HIGHER TERRAIN NORTH AND EAST
OF PHOENIX. AS THE DRIER AIR FILTERS INTO THE REGION...TEMPERATURES
WILL BE ON THE RISE...REACHING NEAR OR SLIGHTLY ABOVE SEASONAL
NORMALS SATURDAY INTO EARLY NEXT WEEK. BY SUNDAY...EVEN THE
SOUTH-CENTRAL LOWER DESERTS SHOULD MAINLY BE DRY AS THE DRY FLOW
SLIDES EASTWARD.
ALTHOUGH WE ARE NOT COMPLETELY SOLD ON THE LONG RANGE MODEL
SOLUTIONS FOR THE MIDDLE OF NEXT WEEK...IT DOES LOOK LIKE A FAIRLY
SIGNIFICANT UPPER LOW MAY MAKE IT/S WAY ACROSS THE SOUTHERN PLAINS
INTO NEW MEXICO BY NEXT TUESDAY. IT IS TOO EARLY TO KNOW HOW MUCH
MOISTURE WILL BE AVAILABLE ACROSS THE REGION...BUT IF THIS SOLUTION
PANS OUT...THE MIDDLE OF NEXT WEEK COULD SEE VERY ACTIVE MONSOON
ACTIVITY ACROSS EASTERN ARIZONA AND POSSIBLY INTO THE LOWER DESERTS.
THE OVERALL FLOW DURING THIS TIME WILL LIKELY BE FROM THE NORTHEAST
ACROSS EASTERN ARIZONA AND FROM THE SOUTH ACROSS FAR WESTERN
ARIZONA. A SCENARIO LIKE THIS WOULD LIKELY RESULT IN DRY CONDITIONS
TO THE WEST OF PHOENIX AND AN ACTIVE MONSOON PERIOD ACROSS THE
HIGHER TERRAIN EAST OF PHOENIX. THE LONG RANGE TEMPERATURE OUTLOOK
SHOULD BRING NORMAL TO SLIGHTLY ABOVE NORMAL TEMPERATURES ACROSS OUR
WESTERN ZONES AND NEAR TO SLIGHTLY BELOW NORMAL FOR SOUTH-CENTRAL
AND EAST-CENTRAL ARIZONA.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX...KIWA AND KSDL...
ABUNDANT MID/HIGH LEVEL CLOUDS WILL AFFECT CNTRL ARIZONA TERMINALS
THROUGH SATURDAY MORNING. SOME AFTERNOON SCT CU WITH BASES AS LOW AS
9K FT MAY DEVELOP...BUT LARGELY CIGS WILL HAVE NO IMPACT. ISOLD/SCT
TSTMS SHOULD REMAIN SOUTH AND EAST OF THE PHOENIX AREA...AND
ALTHOUGH SOME OUTFLOW COULD CONCEIVABLY REACH THESE
SITES...PROBABILITIES AND CONFIDENCE ARE FAR TOO LOW TO INCLUDE ANY
MENTION AT THIS TIME. LIGHT SFC WINDS SHOULD GENERALLY REMAIN OUT OF
A WESTERLY DIRECTION...THOUGH SOME PERIODS OF MORE VARIABLE
DIRECTIONS CAN BE EXPECTED.
SOUTHEAST CA AND SOUTHWEST AZ...INCLUDING KIPL AND KBLH...
PRIMARILY ONLY HIGH CLOUDS WILL COVER SOUTHEAST CALIFORNIA TERMINALS
THROUGH SATURDAY MORNING. MOST MODEL GUIDANCE INDICATES NO SHOWERS
OR TSTMS AFFECTING THIS REGION TODAY...SO HAVE NOT INCLUDED ANY
MENTION IN THIS PACKAGE. SFC WINDS WILL REMAIN LIGHT WITH A WEAK
PRESSURE GRADIENT...AND MOSTLY FROM A S/SW DIRECTION...THOUGH
EXTENDED PERIODS OF A LIGHT AND VARIABLE NATURE CAN BE EXPECTED.
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...PERCHA/KUHLMAN
AVIATION...MO
FIRE WEATHER...CDEWEY
AREA FORECAST DISCUSSION
NWS MIAMI FL
1003 AM EDT FRI JUL 12 2013
.UPDATE...
OUTSIDE OF A FEW MINOR ADJUSTMENTS BASED ON THE LATEST
OBSERVATIONS AND RADAR TRENDS THIS MORNING...THE PREVIOUS FORECAST
PACKAGE REMAINS ON TRACK WITH NO MAJOR UPDATES NECESSARY AT THIS
TIME. THE LATEST WATER LOOP SHOWED AN UPPER LOW SLOWLY DRIFTING
NORTHWARD OVER THE FLORIDA STRAITS TO THE KEYS WITH PLENTY OF
MOISTURE SPREADING NORTH TO ITS EAST OVER THE ADJACENT ATLANTIC
WATERS AND BAHAMAS. THE LATEST SURFACE ANALYSIS A SHOWED A WEAK
TROUGH OF LOW PRESSURE SOUTH AND SOUTHEAST OF THE SRN FLORIDA
PENINSULA ACROSS THE STRAITS AND A WEAK FRONTAL BOUNDARY
EXTENDING WSW FROM SC TO MS. THIS SFC TROUGH NEAR THE AREA
COMBINED WITH THE UPPER LOW WILL CONTINUE TO INFLUENCE THE LOCAL
WEATHER TODAY WITH SCATTERED SHOWERS/TSTMS EXPECTED TO CONTINUE.
THE 12Z MIA SOUNDING SHOWED A VERY MOIST PROFILE WITH 2.03" PW AND
LIGHT SSW FLOW UP TO AROUND THE H4 LEVEL BEFORE SHIFTING TO THE
ENE ALOFT NORTH OF THE UPPER LOW. THE 10Z HRRR MODEL
REFLECTIVITIES LINE ARE IN DECENT AGREEMENT WITH THE LATEST TRENDS AND
INDICATE ACTIVITY INITIATING ALONG THE GULF COAST SEA BREEZE
THROUGH THE EARLY AFTERNOON AND SPREADING ENE TOWARD THE
BROWARD/PALM BEACH COUNTY AREAS THROUGH THE LATE AFTERNOON/EARLY
EVENING HOURS. AS A RESULT...WILL KEEP THE 60 PERCENT RAINFALL
CHANCES IN THE FORECAST ACROSS THE EASTERN HALF OF THE SRN FL
PENINSULA AND UPDATE AS NECESSARY AS CONDITIONS EVOLVE TODAY. 85/AG
&&
.PREV DISCUSSION... /ISSUED 727 AM EDT FRI JUL 12 2013/
AVIATION...
LITTLE CHANGE FROM PREVIOUS FORECAST REASONING. A LIGHT SOUTHWESTERLY
FLOW IS EXPECTED DURING THE MORNING HOURS THEN A DELAYED EAST COAST
SEA BREEZE COULD SET IN AROUND 18Z TO 19Z BUT MAY NOT PENETRATE AS
FAR INLAND TO TERMINAL KTMB. INCREASING DEEPER LAYERED TROPICAL
MOISTURE WILL LEAD TO INCREASING CHANCES OF SHOWERS AND THUNDERSTORMS
FROM LATE MORNING INTO THE AFTERNOON WITH ALL TERMINALS ASSIGNED
VCTS DURING THIS PERIOD. WITH THE OCCURRENCE OF SHOWERS/THUNDERSTORMS
VERY BRIEF PERIODS OF IFR CONDITIONS MAY BE POSSIBLE.
PREV DISCUSSION... /ISSUED 425 AM EDT FRI JUL 12 2013/
HIGHLIGHTS...
* NUMEROUS SHOWERS/TSTORMS EXPECTED TODAY AND SATURDAY WITH LOCALLY
HEAVY RAINS AND GUSTY WINDS POSSIBLE
* LOCALIZED STREET FLOODING POSSIBLE WHERE HEAVIEST STORMS HIT
* WATERSPOUTS POSSIBLE OFF THE SE FL COAST TODAY
DISCUSSION...THE REMNANTS OF CHANTAL WILL MOVE NORTHWARD OFF THE SE
FLORIDA COAST AND ACROSS THE BAHAMAS TODAY. THERE ARE TWO MAIN AREAS
OF CONVECTION THIS MORNING - ONE ASSOCIATED WITH THE LOW LEVEL VORT
AS PER 850 MB VORTICITY CIMMS ANALYSIS, LOCATED BETWEEN CUBA AND
ANDROS ISLAND. THE OTHER AREA OF MORE ROBUST CONVECTION IS
ASSOCIATED WITH A MID LEVEL VORT CENTER OVER THE EASTERN BAHAMAS.
THE SAME THINKING FROM YESTERDAY HOLDS -- NO SIGNIFICANT DIRECT
IMPACTS ARE EXPECTED ACROSS SOUTH FLORIDA. NHC CONTINUES WITH A 30%
CHANCE OF DEVELOPMENT NEXT 48 HR, AND WE OF COURSE CONTINUE TO
MONITOR THIS, BUT THE TIME WINDOW FOR ANY DIRECT LOCAL IMPACTS IS
CLOSING QUICKLY.
THAT BEING SAID, MOISTURE WILL CONTINUE HIGH AROUND THIS FEATURE
TODAY. WE EXPECT DIURNALLY-DRIVEN CONVECTION WITH SHOWERS AND
THUNDERSTORMS BECOMING NUMEROUS ACROSS THE INTERIOR AND THE EAST
COAST METRO AREAS. WE ALREADY HAD DEVELOPMENT ALONG THE MIAMI-DADE
COAST EARLY THIS MORNING. ONE CAVEAT FOR THIS AFTERNOON IS IF THE
REMNANTS BEGIN TO ORGANIZE, THEN ACTIVITY COULD ACTUALLY LESSEN DUE
TO SUBSIDENCE ON THE WESTERN PERIPHERY OF THE FEATURE. HOWEVER, WE
BELIEVE IN THE WETTER SCENARIO, SO KEPT LIKELY POPS FOR THE INTERIOR
AND EAST COAST AND CHANCE POPS GULF COAST.
LOCALLY HEAVY RAINFALL IS A POSSIBILITY TODAY. IN EXCESS OF 3 INCHES
IS POSSIBLE IN ISOLATED LOCALES WHICH WOULD LEAD TO THE POTENTIAL
FOR STREET FLOODING AND FLOODING OF POORLY DRAINED LOCALES. GUSTY
WINDS WILL BE POSSIBLE IN THE STRONGER THUNDERSTORMS AS WELL.
WATERSPOUTS ARE POSSIBLE OFF THE SOUTHEAST FLORIDA COAST TODAY DUE
TO A MOIST ENVIRONMENT WITH A LIGHT WIND FLOW AND SLIGHTLY
FAVORABLE WIND TURNING WITH HEIGHT.
THE COVERAGE OF SHOWERS AND THUNDERSTORMS WILL LESSEN TONIGHT, BUT
KEPT POPS IN AS MOISTURE WILL BE HIGH ALONG WITH SOME CONVERGENCE
NOTED IN THE LOW LEVEL WIND FIELDS. THEN ANOTHER STORMY DAY IS
EXPECTED ON SATURDAY. GFS SHOWS A MOIST SURGE SPREADING ACROSS THE
AREA IN THE MORNING, MOVING NW ACROSS SOUTH FL IN THE AFTERNOON ON
AN INCREASING S-SE WIND. HOWEVER, MORE ACTIVITY COULD DEVELOP AT ANY
TIME SATURDAY GIVEN THE MOIST AND UNSTABLE ATMOSPHERE EXPECTED.
DECIDED TO INCREASE POPS IN LINE WITH THE NEW GFS MOS NUMBERS.
AGAIN, LOCALLY HEAVY RAINFALL IS POSSIBLE ON SATURDAY.
THE WEATHER PATTERN SUNDAY AND BEYOND WILL FEATURE THE ATLANTIC
RIDGE BUILDING BACK IN. A TYPICAL SUMMERTIME PATTERN IS EXPECTED.
THERE IS ONE FEATURE OF NOTE - AN INVERTED TROUGH EAST OF OUR AREA
ALONG ABOUT 55 DEGREES WEST LONGITUDE. THIS FEATURE BROKE OFF FROM
THE MID LATITUDE WESTERLIES AND IS NOW TRAVELING WESTWARD. BOTH
GFS AND ECMWF TRACK THIS TROUGH ACROSS SOUTH FL ON MONDAY, RATHER
AMPLIFIED WITH NE WINDS AHEAD OF IT AND SE WINDS BEHIND IT.
THIS FEATURE COULD ENHANCE SHOWER AND THUNDERSTORM ACTIVITY AS
IT PASSES ON MONDAY.
MARINE...LIGHT WINDS AND SEAS PREVAIL. THE REMNANTS OF CHANTAL
WILL MOVE NORTH ACROSS THE LOCAL WATERS AND THE BAHAMAS TODAY. NHC
GIVES A 30% CHANCE OF RE-DEVELOPMENT OVER THE NEXT 48 HOURS. EVEN
IF THE REMNANTS BEGIN TO RE-DEVELOP TODAY, HIGHER WINDS WOULD BE
EXPECTED TO BE DISPLACED TO THE EAST OF THE CENTER AND OVER THE
BAHAMAS. SO THE FORECAST REFLECTS LIGHT WIND CONDITIONS. HOWEVER,
WINDS COULD BE GUSTY IN A FEW SQUALLS, ESPECIALLY OVER THE
OFFSHORE ATLANTIC WATERS THIS AFTERNOON-EVENING. PREVAILING WINDS
WILL BE OUT OF THE SOUTHERLY DIRECTION THROUGH TOMORROW THEN
BECOMING E-SE SUNDAY AND BEYOND, WITH THE EXCEPTION OF NORTHEAST
WINDS BRIEFLY ON SUN NIGHT INTO MONDAY AHEAD OF THE PASSAGE OF AN
INVERTED SURFACE TROUGH THEN. THIS TROUGH COULD BRING ENHANCED
SHOWER AND THUNDERSTORM ACTIVITY AND POSSIBLY SOMEWHAT HIGHER
WINDS.
FIRE WEATHER...NO CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 89 76 89 75 / 60 40 70 40
FORT LAUDERDALE 89 79 89 77 / 60 40 70 40
MIAMI 89 77 90 77 / 60 40 70 40
NAPLES 87 75 88 75 / 50 30 70 40
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...85/AG
AVIATION/RADAR...10/CD
AREA FORECAST DISCUSSION
NWS TOPEKA KS
624 AM CDT FRI JUL 12 2013
...UPDATE TO AVIATION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 320 AM CDT FRI JUL 12 2013
THE WEATHER PATTERN THIS MORNING DEPICTS THE MID LEVEL RIDGE AXIS
STRETCHING ACROSS THE CENTRAL AND NORTHERN PLAINS. THE RIDGE IS
EXPECTED TO EXPAND NORTHEASTWARD LATER TODAY ESSENTIALLY CUTTING OFF
THE FLOW FROM THE UPPER TROUGH ROTATING OVER THE MID ATLANTIC REGION.
AT THE 08Z HOUR A SUBTLE PERTURBATION EMBEDDED WITHIN THE RIDGE WAS
NOTED OVER SOUTHEAST WYOMING. THE LATEST HRRR AND RAP HAVE TRIED TO
GENERATE PRECIP FOR THE PREVIOUS FEW HOURS NOTING MULTIPLE WEAK
SHORTWAVE TROUGHS THAT ARE NOT OBSERVED IN REAL TIME. AND SINCE NO
FORCING IS APPARENT WILL THEREFORE MONITOR BUT MAINTAIN A DRY
FORECAST FOR THE MORNING PERIOD. A WARMER AND WINDY FRIDAY IS IN
STORE FOR NORTHEAST KANSAS. SURFACE HEATING AND A TIGHTENING
PRESSURE GRADIENT FROM THE H85 SHORTWAVE TROUGH OVER EASTERN
COLORADO WILL PICKUP SOUTHERLY WINDS BETWEEN FROM 15 TO 20 MPH.
THIS WILL ALSO INCREASE WARMER AIR FLOWING INTO THE AREA WITH
READINGS FROM THE LOW 90S IN EAST CENTRAL AREAS...TO THE UPPER 90S
OVER NORTH CENTRAL KS. MOISTURE ADVECTING NORTHWARD WILL KEEP
DEWPOINTS IN THE LOW TO MIDDLE 60S...TRANSLATING TO HEAT INDICES
BETWEEN 100 AND 105 DEGREES OVER NORTH CENTRAL KS. QUIET WEATHER
CONTINUES INTO FRIDAY EVENING WITH STEADY SOUTHEAST WINDS KEEPING
TEMPERATURES WARMER THAN THIS MORNING IN UPPER 60S TO MID 70S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 320 AM CDT FRI JUL 12 2013
FOR SATURDAY THROUGH SUNDAY NIGHT...THE MAIN FOCUS FOR THE
FORECAST IS A RETROGRADING CLOSED LOW MOVING FROM THE TN VALLEY
INTO THE SOUTHERN HIGH PLAINS. MODELS SEEM TO BE SLIGHTLY FASTER
WITH THE PROGRESSION OF THE CLOSED UPPER LOW AND BY SUNDAY NIGHT
HAVE IT OVER THE HIGH PLAINS. ALSO THE MAJORITY OF MODEL SOLUTIONS
TAKE THE UPPER LOW SOUTH OF THE FORECAST AREA WITH THE BETTER
LARGE SCALE FORCING OVER SOUTHERN KS AND OK. CURIOUSLY IT APPEARS
AS THOUGH THERE IS NOT MUCH MID LEVEL MOISTURE ACCOMPANYING THE
LOW WITH THE NAM AND GFS ACTUALLY SHOWING PWS DRYING WITH SURFACE
DEWPOINT TEMPS COOLING AS THE UPPER LOW APPROACHES. ADDITIONALLY
THE MID LEVEL LAPSE RATES ARE PRETTY CLOSE TO THE MOIST ADIABATIC
LAPSE RATE SO THERE IS LITTLE OR NO INSTABILITY ABOVE THE LCL. SO
IN GENERAL AM NOT OVERLY EXCITED ABOUT PRECIP CHANCES THROUGH THE
WEEKEND. WILL KEEP A SLIGHT CHANCE FOR SOME SHOWERS SUNDAY ACROSS
EAST CENTRAL KS THINKING THIS IS THE MOST LIKELY TIME FRAME FOR
THE UPPER LOW TO MOVE THROUGH SOUTHEAST KS. SINCE THERE DOES NOT
APPEAR TO BE ANY INSTABILITY...HAVE REMOVED THE MENTION OF THUNDER
FROM THE FORECAST FOR SUNDAY. HIGHS SHOULD BE TRENDING COOLER
THROUGH THE WEEKEND...ESPECIALLY FOR SUNDAY AS MODELS SHOW LOW
LEVEL COLD AIR ADVECTION FROM THE SOUTHEAST. HIGHS IN THE 90S FOR
SATURDAY SHOULD COOL INTO THE MID 80S TO AROUND 90 FOR SUNDAY.
LOWS WILL ALSO TREND COOLER WITH READINGS FOR SUNDAY MORNING
EXPECTED TO BE IN THE 60S AS SURFACE RIDGING FROM THE EAST
PERSISTS.
MONDAY THROUGH TUESDAY IS A LITTLE MORE UNCERTAIN AS MODELS START
TO DIVERGE ON THE TRACK OF THE CLOSED LOW. THERE IS THE
POSSIBILITY THAT THE UPPER LOW GETS HUNG UP OVER THE HIGH PLAINS
WITH PIECES OF ENERGY ROTATING NORTH INTO THE STATE. BECAUSE OF
THIS HAVE HELD ONTO SOME SLIGHT CHANCE POPS DURING THE DAY MONDAY
AND TUESDAY THINKING THERE COULD BE SOME POP UP STORMS IF THE
UPPER LOW IS JUST TO THE WEST OF THE FORECAST AREA. HIGHS ARE
FORECAST TO REMAIN NEAR NORMAL WITH READINGS AROUND 90. SOUTHERLY
WINDS AND A GRADUAL INCREASE IN LOW LEVEL MOISTURE SHOULD KEEP
LOWS AROUND 70 TO THE LOWER 70S.
THE GFS AND ECMWF SHOW WEAK MID LEVEL RIDGING NOSING INTO EASTERN
KS FROM THE EAST WITH NO REAL SURFACE FEATURE TO FOCUS LIFT OF A
SURFACE PARCEL. BECAUSE OF THIS HAVE MAINTAINED A DRY FORECAST.
TEMPS SHOULD SEE A GRADUAL WARMING TREND AS MID LEVEL HEIGHTS
RISE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 557 AM CDT FRI JUL 12 2013
VFR PREVAILS THROUGH 12Z SATURDAY AT KTOP/KFOE/KMHK AS LIGHT EAST
WINDS VEER TO THE SOUTHEAST AND INCREASE AOA 12 KTS AFT 15Z. AT KMHK
GUSTS WERE INCLUDED NEAR 20 KTS WHERE TERMINAL IS CLOSEST TO
TIGHTER PRESSURE GRADIENT FROM SURFACE TROUGH OVER EASTERN COLORADO.
WINDS WEAKEN BLO 10 KTS AFT 02Z.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BOWEN
LONG TERM...WOLTERS
AVIATION...BOWEN
AREA FORECAST DISCUSSION
NWS HASTINGS NE
925 AM CDT FRI JUL 12 2013
.UPDATE...
ISSUED AT 925 AM CDT FRI JUL 12 2013
THE BIG CHANGE MADE DURING THIS UPDATE WAS HIGH TEMPERATURES FOR
LATER THIS AFTERNOON. BASED ON CURRENT TRENDS...NEW DATA...AND
VERIFICATION STATISTICS...I LOWERED HIGHS THIS AFTERNOON FOR MOST
OF OUR NEBRASKA COUNTIES. THIS WAS NOT A DRASTIC CHANGE...BUT
MOST LOCATIONS WERE LOWERED TWO TO THREE DEGREES. PHILLIPS AND
ROOKS COUNTIES IN KANSAS WERE ACTUALLY RAISED A DEGREE OR
TWO...OTHERWISE...TEMPERATURES ACROSS KANSAS STAYED RELATIVELY
CLOSE TO THE PREVIOUS FORECAST. DEW POINTS WERE ALSO UPDATED TO
REFLECT TRENDS AND NEW DATA.
UPDATE ISSUED AT 635 AM CDT FRI JUL 12 2013
THE NARROW LINE OF ACCAS-INDUCED SPRINKLES/SHOWERS THAT EARLIER
STARTED TO DEVELOP WITHIN THE EASTERN FRINGES OF THE CWA HAS SINCE
ADVECTED 1+ COUNTY EAST OF OUR AREA PER THE LATEST RADAR/SATELLITE
TRENDS. THUS WILL FORGE AHEAD WITH NO PRECIP MENTION WHATSOEVER
THROUGH THE NEXT 24 HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 431 AM CDT FRI JUL 12 2013
THE PRIMARY ISSUE DURING THE NEXT 24 HOURS IS DETERMINING HOW HOT
WE ACTUALLY GET TODAY/HOW CLOSE WE GET TO HEAT ADVISORY
CRITERIA...AND HOW CLOSE TO CRITICAL FIRE DANGER WESTERN PARTS OF
NORTH CENTRAL KANSAS MIGHT GET. ALTHOUGH THE FORECAST PRODUCTS
CARRY NO MENTION OF SHOWERS/THUNDERSTORMS DUE TO POPS HOLDING BELOW
15 PERCENT...POPS ARE NOT NECESSARILY ZERO...AND WILL HAVE TO KEEP
AN EYE ESPECIALLY ON FAR WESTERN/NORTHERN COUNTIES LATE THIS
AFTERNOON-TONIGHT FOR THE REMOTE CHANCE THAT A FEW STORMS COULD
POP UP OR MOVE IN FROM THE WEST/NORTH. IN THE IMMEDIATE NEXT FEW
HOURS...ITS NOT COMPLETELY OUT OF THE QUESTION THAT A FEW HIGH-
BASED SHOWERS/STORMS COULD TRY DEVELOPING IN EASTERN ZONES BEFORE
SUNRISE.
08Z OBJECTIVE SURFACE ANALYSIS REVEALS A FAIRLY ILL-DEFINED QUASI-
STATIONARY FRONT SNAKING FROM A 1000 MILLIBAR LOW IN NORTHWEST
SD...SOUTHWARD THROUGH WESTERN NEBRASKA INTO NORTHWEST/SOUTH CENTRAL
KS. OFF TO THE EAST...A 1019MB HIGH IS CENTERED NEAR THE IA/IL
BORDER. BETWEEN THE FRONT AND THE HIGH...FAIRLY STEADY SOUTH-
SOUTHEAST BREEZES OF 8-15 MPH WITH OCCASIONAL GUSTS OVER 20 ARE IN
PLACE ACROSS THE CWA EARLY THIS MORNING...WITH THESE BREEZES
EXPECTED TO HELP HOLD LOW TEMPS UP BETWEEN 69-74 IN MOST AREAS.
ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA HIGHLIGHT A
FAIRLY EXPANSIVE MID/UPPER LEVEL RIDGE AXIS THAT HAS BUILT
NORTHEAST SINCE 24 HOURS AGO TO ENCOMPASS MUCH OF THE
CENTRAL/SOUTH CENTRAL CONUS. THE CENTER AXIS OF THIS RIDGE...AT
ROUGHLY 590 DECAMETER...RUNS FROM ROUGHLY THE LOCAL CWA ON THE
NORTHEAST EDGE...BACK SOUTHWESTWARD TOWARD THE NM/TX BORDER. WITH
THIS RIDGE AXIS NEARLY OVERHEAD...THE FLOW OVER THE CWA AT 500MB
IS FAIRLY LIGHT/VARIABLE...WHILE A BIT LOWER AT 700MB...THERE IS
MODEST WEST-SOUTHWEST FLOW. A NARROW ZONE OF THETA-E ADVECTION
ALONG A FAIRLY TIGHT 700MB MOISTURE GRADIENT HAS RESULTED IN A
SCATTERED ACCAS FIELD WITHIN ROUGHLY THE EASTERN 1/3 OF THE CWA
TONIGHT...AND RECENTLY THE FIRST FEW HINTS OF ISOLATED ELEVATED
SPRINKLES/LIGHT SHOWERS HAVE SHOWED UP ON RADAR WITHIN A FEW OF
OUR EASTERN COUNTIES.
STARTING WITH THE MOST IMMEDIATE ISSUE...WILL BE CLOSELY
MONITORING RADAR TRENDS IN EASTERN ZONES PRIOR TO SUNRISE TO SEE
WHETHER THE AFOREMENTIONED VERY ISOLATED CONVECTION CAN BE COVERED
WITH A SPRINKLE MENTION...OR MIGHT NEED SOMETHING MORE.
THE LATEST RAP HAS CAUGHT ONTO THIS DEVELOPMENT...AND SUGGESTS
THAT MAINLY OUR FAR EASTERN COUNTIES NEAR THE HWY 81 CORRIDOR
COULD CONTINUE TO SEE SOME OF THIS PRE-DAWN ACTIVITY...BUT THAT IT
SHOULD LARGELY BE DONE OR ADVECTED EAST OF THE CWA BY 7AM/12Z. PER
FORECAST SOUNDINGS...PARCELS ROOTED NEAR 700MB COULD POTENTIALLY
HAVE UP TO AROUND 400 J/KG MUCAPE AVAILABLE TO THEM...SO A BRIEF
FLARE UP OF NON-SEVERE THUNDERSTORMS IS NOT COMPLETELY OUT OF THE
QUESTION. FOR NOW...WILL ONLY MENTION ISOLATED SPRINKLES IN OUR
EASTERN FEW COLUMNS OF NEBRASKA COUNTIES THROUGH 12Z TO COVER
THINGS...PENDING ANY EVIDENCE OTHERWISE.
TURNING TO THE DAYTIME HOURS...THE MAIN STORY WILL BE A RETURN OF
LEGITIMATE SUMMER HEAT...BUT DOES NOT APPEAR TO BE HEADLINE-
WORTHY. IN THE MID/UPPER LEVELS...THE DOMINANT RIDGE AXIS WILL
CONTINUE TO EXPAND ACROSS THE CENTRAL PLAINS IN A SOUTHWEST-
NORTHEAST FASHION...WITH PARTS OF THE CWA ALIGNED ALMOST DIRECTLY
UNDER ITS CENTER AXIS. AT THE SURFACE...A FAIRLY SHARP TROUGH
AXIS WILL SET UP FROM FAR EASTERN CO ACROSS NORTHWEST NEB INTO
CENTRAL SD BY MID-LATE AFTERNOON...EXTENDING FROM A ROUGHLY 1000MB
LOW CENTERED NEAR THE CO/KS BORDER. THE LOCAL CWA WILL REMAIN IN
THE OPEN WARM SECTOR SOLIDLY SOUTHEAST OF THIS TROUGH AXIS...AND
THUS WILL SEE A CONTINUATION OF FAIRLY BREEZY SOUTH-SOUTHEAST
WINDS...WITH SUSTAINED SPEEDS MOST ALL AREAS 15-20 MPH AND GUSTS
25 TO POSSIBLY 30 MPH AT TIMES. AS FOR CONVECTIVE CHANCES...ASIDE
FROM ANY EARLY MORNING ACTIVITY IN THE EAST...THERE IS LITTLE IF
ANY RISK OF SHOWERS/STORMS TODAY AS WARM MID LEVEL TEMPS WITHIN
THE RIDGE AXIS SHOULD SERVE TO CAP THINGS OFF PRETTY SOLIDLY. ONE
OF THE ONLY POSSIBLE CAVEATS...AS DEPICTED BY THE LATEST RAP
RUNS...IS THAT STRONG HEATING AND VERY DEEP MIXING COULD POP A FEW
HIGH-BASED STORMS LATE IN THE AFTERNOON ALONG WESTERN PORTIONS OF
THE NEB/KS BORDER...WITH SOME OF THIS ACTIVITY POSSIBLY ADVECTING
EAST INTO THE DAWSON-FURNAS COUNTY CORRIDOR...BUT THE ODDS OF THIS
SEEM LOW ENOUGH TO STICK WITH SILENT 10 POPS FOR NOW...AS MOST
LATE AFTERNOON STORMS SHOULD FOCUS WELL TO OUR NORTHWEST ALONG THE
AFOREMENTIONED TROUGH AXIS. TEMP-WISE...BASED ON HOW HIGHS TURNED
OUT YESTERDAY...IT APPEARS THE NAM AND ASSOCIATED MET GUIDANCE HAS
BEEN A BIT AGGRESSIVE WITH THE HEAT...AND AS A RESULT...HAVE
SHAVED A FEW DEGREES OFF HIGHS TODAY IN MOST AREAS...USING VALUES
A BIT CLOSER TO GFS MAV GUIDANCE AND A MULTI-MODEL BLEND. THIS STILL
YIELDS A VERY TOASTY DAY WITH HIGHS RANGING FROM MID 90S NORTHEAST
...MID-UPPER 90S CENTRAL AND UPPER 90S TO AROUND 102 IN KS ZONES
AND NEAR THE STATE LINE. AS FOR DEWPOINTS...NOT EXPECTING A
DRAMATIC MIX-DOWN TODAY GIVEN THAT WINDS WILL BE MORE SOUTHERLY
VERSUS SOUTHWESTERLY...BUT NUDGED THEM DOWN A BIT ESPECIALLY IN
WESTERN ZONES...RANGING FROM UPPER 50S AT MID-AFTERNOON IN THE FAR
WEST TO MID-UPPER 60S IN THE EAST. THE RESULTANT HEAT INDEX VALUES
PEAK IN THE 98-100 RANGE ACROSS MOST OF THE NEB CWA...WITH KS
ZONES AND AREAS NEAR THE STATE LINE MORE LIKELY TO REACH THE
101-104 RANGE. BOTTOM LINE HERE IS...THESE VALUES ARE CERTAINLY
WORTH A HAZARDOUS WEATHER OUTLOOK MENTION...BUT DO NOT JUSTIFY A
FORMAL HEAT ADVISORY BASED ON OUR 105+ LOCAL CRITERIA. PLEASE NOTE
THAT THE NORTH PLATTE/LBF CWA HAS A SLIGHTLY COOLER
...CLIMATOLOGICALLY-BASED HEAT ADVISORY CRITERIA OF 100+...AND
THIS IS WHY A FORMAL HEADLINE IS OUT FOR THEIR AREA...BUT NOT FOR
OURS.
TURNING TO THIS EVENING/TONIGHT POST-7PM/00Z...THE MAIN STORY
VERSUS PREVIOUS FORECAST IS THAT THE SLIGHT CHANCE OF
THUNDERSTORMS HAS BEEN TRIMMED FROM THE EXTREME NORTHERN/WEST-
CENTRAL EDGES OF THE CWA...AND THUS WILL CARRY A STORM-FREE
FORECAST CWA-WIDE. AGAIN THOUGH...WILL EMPHASIZE THAT SILENT 10
POPS WILL REMAIN IN PLACE ESPECIALLY IN NORTHERN/WESTERN COUNTIES
TO AT LEAST ACKNOWLEDGE THAT A VERY LOW PROBABILITY OF SOME
ACTIVITY IS NOT COMPLETELY OUT OF THE QUESTION. IN THE MID-UPPER
LEVELS...THERE IS VERY LITTLE CHANGE WITH THE STRENGTH/ORIENTATION
OF THE EXPANSIVE RIDGE AXIS...AS IT REMAINS DRAPED FROM SOUTHWEST-
NORTHEAST ACROSS THE HEART OF THE CENTRAL PLAINS. A BIT LOWER AT
850MB...A 40+KT SOUTHERLY LOW LEVEL JET CRANKS UP THROUGH THE
NIGHT FROM WESTERN KS ACROSS CENTRAL NEB INTO EASTERN SD/WESTERN
MN...HELPING TO FOCUS THE VAST MAJORITY OF REGIONAL CONVECTION
NEAR THE EXIT REGION OF THIS FEATURE FROM NORTHEAST CO ACROSS
NORTHWEST NEB INTO SD/MN. AT THE SURFACE...THERE WILL ALSO BE
LITTLE OVERALL CHANGE FROM THE DAYTIME HOURS...WITH THE TROUGH
AXIS PERSISTING FROM NEAR THE KS/CO BORDER NORTH-NORTHEAST INTO
CENTRAL SD. WITH A CONTINUED MODEST PRESSURE GRADIENT AND LIMITED
MIXING UNDER THE LOW LEVEL JET...SURFACE BREEZES ACROSS THE CWA
WILL AGAIN AVERAGE 10-15 MPH FROM THE SOUTH-SOUTHEAST. ASSUMING
THAT POTENTIALLY ROGUE LATE AFTERNOON/EARLY EVENING STORMS DO NOT
AFFECT THE FAR WESTERN CWA...ITS PRETTY APPARENT FROM MOST MODEL
DEPICTIONS THAT OVERNIGHT CONVECTION SHOULD FOCUS AT LEAST 50-100
MILES NORTH THROUGH NORTHWEST OF THE CWA...AND GENERALLY LIFT
NORTH WITH TIME. THE ONLY FORESEEABLE CAVEAT HERE WOULD BE IF
NORTHERN NEB STORMS DEVELOP A COLD POOL AND START TO BUILD
SOUTHWARD INTO THE LOW LEVEL JET AXIS...POTENTIALLY REACHING THE
NORTHERN PARTS OF THE CWA. INTERESTINGLY...AT LEAST ONE
MODEL...THE 4KM WRF-NMM FROM PSU...DOES DEPICT THIS SCENARIO...BUT
GIVEN SUCH LIMITED SUPPORT WILL KEEP IT STORM-FREE FOR NOW. WILL
ALSO NOTE THAT THE 00Z GFS DEPICTION OF LATE NIGHT STORMS FLARING
UP NEAR HIGHWAY 81...LIKELY IN RESPONSE TO ANOTHER SUBTLE BATCH OF
MID LEVEL THETA-E ADVECTION...HAS BEEN DISREGARDED AS AN OUTLIER
AS WELL FOR THIS FORECAST. LOW TEMPERATURES WERE CHANGED
LITTLE...AND AGAIN REFLECT A SLIGHT UPWARD TREND FROM THE PAST FEW
NIGHTS...WITH MOST AREAS PROGGED TO BOTTOM OUT 72-75.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 431 AM CDT FRI JUL 12 2013
FOCUS FOR THIS TIMEFRAME WILL INVOLVE BOTH HIGH TEMPERATURES AND
PRECIPITATION CHANCES. MOST OF THE OPERATIONAL MODELS ARE COMING
INTO AGREEMENT ON THE UNUSUAL PATTERN EXPECTED IN THE SATURDAY TO
THURSDAY PERIOD. THEY ARE TAKING THE MID/UPPER LEVEL LOW PRESSURE
CURRENTLY SITTING OVER OHIO...AND RETROGRADING IT BACK TO THE
WEST. BY 12Z SAT THE GFS HAS IT OVER CENTRAL TENN...WHILE THE EC
PLACES IT A LITTLE NORTH OF THERE OVER KENTUCKY...AND THE NAM IS
BETWEEN THE TWO. BY 12Z SUNDAY THESE MODELS HAVE IT FROM CENTRAL
MISSOURI TO WESTERN ARKANSAS. THIS WESTWARD PUSH IS PROGGED TO
CONTINUE AND BY 12Z MONDAY IT IS FORECAST TO BE FROM NORTHERN
OKLAHOMA TO NORTHERN TEXAS. IT THEN APPEARS TO REMAIN OVER THE
TEXAS PANHANDLE OR IN NORTHEASTERN NEW MEXICO WHILE GRADUALLY
FILLING INTO THE WORKWEEK.
THIS IS NOT A VERY COMMON SCENARIO AND IF IT DOES COME TO FRUITION
WOULD MEAN COOLER TEMPERATURES STARTING SUNDAY. IN THE PAST 24
HRS...THE EXPECTED 850 MB TEMPS FOR SUNDAY OVER OUR AREA HAVE
DECREASED ABOUT 8-10 DEGREES C. GIVEN THE CONSISTENCY OF THE VARIOUS
OPERATIONAL MODELS WILL BUY INTO THIS SCENARIO AND LOWER HIGHS ON
SUNDAY BY SEVERAL DEGREES. SIMILAR TEMPERATURES CAN BE EXPECTED ON
MONDAY AND TUESDAY. WHILE COOLER THAN THOSE EXPECTED FOR TODAY AND
SATURDAY...WOULD NOT EXACTLY CALL IT COOL WEATHER AS HIGHS WILL
ACTUALLY BE AROUND NORMAL FOR THIS TIME OF YEAR FOR SUN-TUES. AFTER
THAT WE SHOULD SEE A GRADUAL WARMUP AS RIDGE RE-ESTABLISHES ITSELF
OVER THE REGION.
PRECIPITATION CONTINUES TO BE DIFFICULT TO FORECAST. LOOKS LIKE
THERE ARE AT LEAST SLIGHT CHANCES ON SAT AND SUNDAY NIGHTS OVER MUCH
OF THE CWA WITH A SURFACE BOUNDARY JUST TO OUR WEST...WEAK WAVES
ROTATING JUST TO OUR NORTH ALONG THE NORTHERN JET...AND THE
APPROACHING RETROGRADING LOW MENTIONED ABOVE. WILL CONTINUE TO
FORECAST DRY WEATHER FOR THE UPCOMING WORKWEEK BUT THAT MAY CHANGE
DEPENDING HOW FAR NORTH THAT RETROGRADING LOW TRACKS. AT
PRESENT...IT MAY AFFECT THE KANSAS PART OF OUR CWA BUT THE FURTHER
NORTH ITS TRACK...THE BETTER THE CHANCE FOR SOME RAIN IN THE NEB
PART OF OUR CWA.
&&
.AVIATION...(FOR THE 12Z KGRI TAF THROUGH 12Z SATURDAY MORNING)
ISSUED AT 630 AM CDT FRI JUL 12 2013
THERE IS FAIRLY HIGH CONFIDENCE THAT VFR CEILING/VISIBILITY WILL
PREVAIL THROUGH THE PERIOD...WITH MID/UPPER LEVEL HIGH PRESSURE
DOMINATING THE LOCAL WEATHER PATTERN AND PROVIDING MOSTLY CLEAR
SKIES...AND VERY LITTLE IF ANY RISK OF A SHOWER/THUNDERSTORM. AS
FOR SURFACE WINDS...A RATHER CONSTANT SOUTH-SOUTHEAST DIRECTION
WILL PREVAIL THROUGHOUT THE PERIOD...AND IT WILL REMAIN FAIRLY
BREEZY MOST OF THE TIME...WITH GUSTS COMMONLY UP TO AROUND
18KT...AND DAYTIME GUST POTENTIAL TO AT LEAST 25KT. THE ONLY REAL
ISSUE OF NOTE IS LOW LEVEL WIND SHEAR UNDERNEATH A NOCTURNAL LOW
LEVEL JET. WILL CONTINUE A MENTION OF MARGINAL LLWS FOR THE FIRST
FEW HOURS THIS MORNING...AND THEN BRING BACK ANOTHER ROUND OF LLWS
FOR THE EARLY SATURDAY MORNING HOURS THANKS TO A SIMILAR
SETUP...WITH 30+KT OF BULK SHEAR DIFFERENCE BETWEEN THE SURFACE
AND APPROXIMATELY 1500 FT AGL...WHERE SUSTAINED SOUTH-SOUTHWEST
WINDS UP TO AROUND 43KT WILL DEVELOP.
&&
.FIRE WEATHER...
ISSUED AT 431 AM CDT FRI JUL 12 2013
ALTHOUGH CRITICAL FIRE WEATHER CONDITIONS/DANGER ARE NOT
ANTICIPATED WITHIN THE CWA TODAY...NEAR-CRITICAL CONDITIONS ARE
FORECAST ESPECIALLY IN THE FAR SOUTHWEST IN THE PHILLIPS/ROOKS
COUNTY AREAS...AND THUS WILL INTRODUCE THIS MENTION INTO THE
HAZARDOUS WEATHER OUTLOOK. THIS AREA WILL FEATURE THE GREATEST
OVERLAP OF SUSTAINED WINDS/GUSTS 20/25 MPH...AND RELATIVE HUMIDITY
VALUES NEAR OR SLIGHTLY BELOW 25 PERCENT. CERTAINLY...AT LEAST A
LIMITED FIRE DANGER WILL EXIST ELSEWHERE ACROSS THE CWA GIVEN THE
STEADY BREEZES AND OVERALL DRY CONDITIONS OF LATE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...GUERRERO
SHORT TERM...PFANNKUCH
LONG TERM...EWALD
AVIATION...PFANNKUCH
FIRE WEATHER...PFANNKUCH
AREA FORECAST DISCUSSION...CORRECTED
NWS HASTINGS NE
638 AM CDT FRI JUL 12 2013
.UPDATE...
ISSUED AT 635 AM CDT FRI JUL 12 2013
THE NARROW LINE OF ACCAS-INDUCED SPRINKLES/SHOWERS THAT EARLIER
STARTED TO DEVELOP WITHIN THE EASTERN FRINGES OF THE CWA HAS SINCE
ADVECTED 1+ COUNTY EAST OF OUR AREA PER THE LATEST RADAR/SATELLITE
TRENDS. THUS WILL FORGE AHEAD WITH NO PRECIP MENTION WHATSOEVER
THROUGH THE NEXT 24 HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 431 AM CDT FRI JUL 12 2013
THE PRIMARY ISSUE DURING THE NEXT 24 HOURS IS DETERMINING HOW HOT
WE ACTUALLY GET TODAY/HOW CLOSE WE GET TO HEAT ADVISORY
CRITERIA...AND HOW CLOSE TO CRITICAL FIRE DANGER WESTERN PARTS OF
NORTH CENTRAL KANSAS MIGHT GET. ALTHOUGH THE FORECAST PRODUCTS
CARRY NO MENTION OF SHOWERS/THUNDERSTORMS DUE TO POPS HOLDING BELOW
15 PERCENT...POPS ARE NOT NECESSARILY ZERO...AND WILL HAVE TO KEEP
AN EYE ESPECIALLY ON FAR WESTERN/NORTHERN COUNTIES LATE THIS
AFTERNOON-TONIGHT FOR THE REMOTE CHANCE THAT A FEW STORMS COULD
POP UP OR MOVE IN FROM THE WEST/NORTH. IN THE IMMEDIATE NEXT FEW
HOURS...ITS NOT COMPLETELY OUT OF THE QUESTION THAT A FEW HIGH-
BASED SHOWERS/STORMS COULD TRY DEVELOPING IN EASTERN ZONES BEFORE
SUNRISE.
08Z OBJECTIVE SURFACE ANALYSIS REVEALS A FAIRLY ILL-DEFINED QUASI-
STATIONARY FRONT SNAKING FROM A 1000 MILLIBAR LOW IN NORTHWEST
SD...SOUTHWARD THROUGH WESTERN NEBRASKA INTO NORTHWEST/SOUTH CENTRAL
KS. OFF TO THE EAST...A 1019MB HIGH IS CENTERED NEAR THE IA/IL
BORDER. BETWEEN THE FRONT AND THE HIGH...FAIRLY STEADY SOUTH-
SOUTHEAST BREEZES OF 8-15 MPH WITH OCCASIONAL GUSTS OVER 20 ARE IN
PLACE ACROSS THE CWA EARLY THIS MORNING...WITH THESE BREEZES
EXPECTED TO HELP HOLD LOW TEMPS UP BETWEEN 69-74 IN MOST AREAS.
ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA HIGHLIGHT A
FAIRLY EXPANSIVE MID/UPPER LEVEL RIDGE AXIS THAT HAS BUILT
NORTHEAST SINCE 24 HOURS AGO TO ENCOMPASS MUCH OF THE
CENTRAL/SOUTH CENTRAL CONUS. THE CENTER AXIS OF THIS RIDGE...AT
ROUGHLY 590 DECAMETER...RUNS FROM ROUGHLY THE LOCAL CWA ON THE
NORTHEAST EDGE...BACK SOUTHWESTWARD TOWARD THE NM/TX BORDER. WITH
THIS RIDGE AXIS NEARLY OVERHEAD...THE FLOW OVER THE CWA AT 500MB
IS FAIRLY LIGHT/VARIABLE...WHILE A BIT LOWER AT 700MB...THERE IS
MODEST WEST-SOUTHWEST FLOW. A NARROW ZONE OF THETA-E ADVECTION
ALONG A FAIRLY TIGHT 700MB MOISTURE GRADIENT HAS RESULTED IN A
SCATTERED ACCAS FIELD WITHIN ROUGHLY THE EASTERN 1/3 OF THE CWA
TONIGHT...AND RECENTLY THE FIRST FEW HINTS OF ISOLATED ELEVATED
SPRINKLES/LIGHT SHOWERS HAVE SHOWED UP ON RADAR WITHIN A FEW OF
OUR EASTERN COUNTIES.
STARTING WITH THE MOST IMMEDIATE ISSUE...WILL BE CLOSELY
MONITORING RADAR TRENDS IN EASTERN ZONES PRIOR TO SUNRISE TO SEE
WHETHER THE AFOREMENTIONED VERY ISOLATED CONVECTION CAN BE COVERED
WITH A SPRINKLE MENTION...OR MIGHT NEED SOMETHING MORE.
THE LATEST RAP HAS CAUGHT ONTO THIS DEVELOPMENT...AND SUGGESTS
THAT MAINLY OUR FAR EASTERN COUNTIES NEAR THE HWY 81 CORRIDOR
COULD CONTINUE TO SEE SOME OF THIS PRE-DAWN ACTIVITY...BUT THAT IT
SHOULD LARGELY BE DONE OR ADVECTED EAST OF THE CWA BY 7AM/12Z. PER
FORECAST SOUNDINGS...PARCELS ROOTED NEAR 700MB COULD POTENTIALLY
HAVE UP TO AROUND 400 J/KG MUCAPE AVAILABLE TO THEM...SO A BRIEF
FLARE UP OF NON-SEVERE THUNDERSTORMS IS NOT COMPLETELY OUT OF THE
QUESTION. FOR NOW...WILL ONLY MENTION ISOLATED SPRINKLES IN OUR
EASTERN FEW COLUMNS OF NEBRASKA COUNTIES THROUGH 12Z TO COVER
THINGS...PENDING ANY EVIDENCE OTHERWISE.
TURNING TO THE DAYTIME HOURS...THE MAIN STORY WILL BE A RETURN OF
LEGITIMATE SUMMER HEAT...BUT DOES NOT APPEAR TO BE HEADLINE-
WORTHY. IN THE MID/UPPER LEVELS...THE DOMINANT RIDGE AXIS WILL
CONTINUE TO EXPAND ACROSS THE CENTRAL PLAINS IN A SOUTHWEST-
NORTHEAST FASHION...WITH PARTS OF THE CWA ALIGNED ALMOST DIRECTLY
UNDER ITS CENTER AXIS. AT THE SURFACE...A FAIRLY SHARP TROUGH
AXIS WILL SET UP FROM FAR EASTERN CO ACROSS NORTHWEST NEB INTO
CENTRAL SD BY MID-LATE AFTERNOON...EXTENDING FROM A ROUGHLY 1000MB
LOW CENTERED NEAR THE CO/KS BORDER. THE LOCAL CWA WILL REMAIN IN
THE OPEN WARM SECTOR SOLIDLY SOUTHEAST OF THIS TROUGH AXIS...AND
THUS WILL SEE A CONTINUATION OF FAIRLY BREEZY SOUTH-SOUTHEAST
WINDS...WITH SUSTAINED SPEEDS MOST ALL AREAS 15-20 MPH AND GUSTS
25 TO POSSIBLY 30 MPH AT TIMES. AS FOR CONVECTIVE CHANCES...ASIDE
FROM ANY EARLY MORNING ACTIVITY IN THE EAST...THERE IS LITTLE IF
ANY RISK OF SHOWERS/STORMS TODAY AS WARM MID LEVEL TEMPS WITHIN
THE RIDGE AXIS SHOULD SERVE TO CAP THINGS OFF PRETTY SOLIDLY. ONE
OF THE ONLY POSSIBLE CAVEATS...AS DEPICTED BY THE LATEST RAP
RUNS...IS THAT STRONG HEATING AND VERY DEEP MIXING COULD POP A FEW
HIGH-BASED STORMS LATE IN THE AFTERNOON ALONG WESTERN PORTIONS OF
THE NEB/KS BORDER...WITH SOME OF THIS ACTIVITY POSSIBLY ADVECTING
EAST INTO THE DAWSON-FURNAS COUNTY CORRIDOR...BUT THE ODDS OF THIS
SEEM LOW ENOUGH TO STICK WITH SILENT 10 POPS FOR NOW...AS MOST
LATE AFTERNOON STORMS SHOULD FOCUS WELL TO OUR NORTHWEST ALONG THE
AFOREMENTIONED TROUGH AXIS. TEMP-WISE...BASED ON HOW HIGHS TURNED
OUT YESTERDAY...IT APPEARS THE NAM AND ASSOCIATED MET GUIDANCE HAS
BEEN A BIT AGGRESSIVE WITH THE HEAT...AND AS A RESULT...HAVE
SHAVED A FEW DEGREES OFF HIGHS TODAY IN MOST AREAS...USING VALUES
A BIT CLOSER TO GFS MAV GUIDANCE AND A MULTI-MODEL BLEND. THIS STILL
YIELDS A VERY TOASTY DAY WITH HIGHS RANGING FROM MID 90S NORTHEAST
...MID-UPPER 90S CENTRAL AND UPPER 90S TO AROUND 102 IN KS ZONES
AND NEAR THE STATE LINE. AS FOR DEWPOINTS...NOT EXPECTING A
DRAMATIC MIX-DOWN TODAY GIVEN THAT WINDS WILL BE MORE SOUTHERLY
VERSUS SOUTHWESTERLY...BUT NUDGED THEM DOWN A BIT ESPECIALLY IN
WESTERN ZONES...RANGING FROM UPPER 50S AT MID-AFTERNOON IN THE FAR
WEST TO MID-UPPER 60S IN THE EAST. THE RESULTANT HEAT INDEX VALUES
PEAK IN THE 98-100 RANGE ACROSS MOST OF THE NEB CWA...WITH KS
ZONES AND AREAS NEAR THE STATE LINE MORE LIKELY TO REACH THE
101-104 RANGE. BOTTOM LINE HERE IS...THESE VALUES ARE CERTAINLY
WORTH A HAZARDOUS WEATHER OUTLOOK MENTION...BUT DO NOT JUSTIFY A
FORMAL HEAT ADVISORY BASED ON OUR 105+ LOCAL CRITERIA. PLEASE NOTE
THAT THE NORTH PLATTE/LBF CWA HAS A SLIGHTLY COOLER
...CLIMATOLOGICALLY-BASED HEAT ADVISORY CRITERIA OF 100+...AND
THIS IS WHY A FORMAL HEADLINE IS OUT FOR THEIR AREA...BUT NOT FOR
OURS.
TURNING TO THIS EVENING/TONIGHT POST-7PM/00Z...THE MAIN STORY
VERSUS PREVIOUS FORECAST IS THAT THE SLIGHT CHANCE OF
THUNDERSTORMS HAS BEEN TRIMMED FROM THE EXTREME NORTHERN/WEST-
CENTRAL EDGES OF THE CWA...AND THUS WILL CARRY A STORM-FREE
FORECAST CWA-WIDE. AGAIN THOUGH...WILL EMPHASIZE THAT SILENT 10
POPS WILL REMAIN IN PLACE ESPECIALLY IN NORTHERN/WESTERN COUNTIES
TO AT LEAST ACKNOWLEDGE THAT A VERY LOW PROBABILITY OF SOME
ACTIVITY IS NOT COMPLETELY OUT OF THE QUESTION. IN THE MID-UPPER
LEVELS...THERE IS VERY LITTLE CHANGE WITH THE STRENGTH/ORIENTATION
OF THE EXPANSIVE RIDGE AXIS...AS IT REMAINS DRAPED FROM SOUTHWEST-
NORTHEAST ACROSS THE HEART OF THE CENTRAL PLAINS. A BIT LOWER AT
850MB...A 40+KT SOUTHERLY LOW LEVEL JET CRANKS UP THROUGH THE
NIGHT FROM WESTERN KS ACROSS CENTRAL NEB INTO EASTERN SD/WESTERN
MN...HELPING TO FOCUS THE VAST MAJORITY OF REGIONAL CONVECTION
NEAR THE EXIT REGION OF THIS FEATURE FROM NORTHEAST CO ACROSS
NORTHWEST NEB INTO SD/MN. AT THE SURFACE...THERE WILL ALSO BE
LITTLE OVERALL CHANGE FROM THE DAYTIME HOURS...WITH THE TROUGH
AXIS PERSISTING FROM NEAR THE KS/CO BORDER NORTH-NORTHEAST INTO
CENTRAL SD. WITH A CONTINUED MODEST PRESSURE GRADIENT AND LIMITED
MIXING UNDER THE LOW LEVEL JET...SURFACE BREEZES ACROSS THE CWA
WILL AGAIN AVERAGE 10-15 MPH FROM THE SOUTH-SOUTHEAST. ASSUMING
THAT POTENTIALLY ROGUE LATE AFTERNOON/EARLY EVENING STORMS DO NOT
AFFECT THE FAR WESTERN CWA...ITS PRETTY APPARENT FROM MOST MODEL
DEPICTIONS THAT OVERNIGHT CONVECTION SHOULD FOCUS AT LEAST 50-100
MILES NORTH THROUGH NORTHWEST OF THE CWA...AND GENERALLY LIFT
NORTH WITH TIME. THE ONLY FORESEEABLE CAVEAT HERE WOULD BE IF
NORTHERN NEB STORMS DEVELOP A COLD POOL AND START TO BUILD
SOUTHWARD INTO THE LOW LEVEL JET AXIS...POTENTIALLY REACHING THE
NORTHERN PARTS OF THE CWA. INTERESTINGLY...AT LEAST ONE
MODEL...THE 4KM WRF-NMM FROM PSU...DOES DEPICT THIS SCENARIO...BUT
GIVEN SUCH LIMITED SUPPORT WILL KEEP IT STORM-FREE FOR NOW. WILL
ALSO NOTE THAT THE 00Z GFS DEPICTION OF LATE NIGHT STORMS FLARING
UP NEAR HIGHWAY 81...LIKELY IN RESPONSE TO ANOTHER SUBTLE BATCH OF
MID LEVEL THETA-E ADVECTION...HAS BEEN DISREGARDED AS AN OUTLIER
AS WELL FOR THIS FORECAST. LOW TEMPERATURES WERE CHANGED
LITTLE...AND AGAIN REFLECT A SLIGHT UPWARD TREND FROM THE PAST FEW
NIGHTS...WITH MOST AREAS PROGGED TO BOTTOM OUT 72-75.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 431 AM CDT FRI JUL 12 2013
FOCUS FOR THIS TIMEFRAME WILL INVOLVE BOTH HIGH TEMPERATURES AND
PRECIPITATION CHANCES. MOST OF THE OPERATIONAL MODELS ARE COMING
INTO AGREEMENT ON THE UNUSUAL PATTERN EXPECTED IN THE SATURDAY TO
THURSDAY PERIOD. THEY ARE TAKING THE MID/UPPER LEVEL LOW PRESSURE
CURRENTLY SITTING OVER OHIO...AND RETROGRADING IT BACK TO THE
WEST. BY 12Z SAT THE GFS HAS IT OVER CENTRAL TENN...WHILE THE EC
PLACES IT A LITTLE NORTH OF THERE OVER KENTUCKY...AND THE NAM IS
BETWEEN THE TWO. BY 12Z SUNDAY THESE MODELS HAVE IT FROM CENTRAL
MISSOURI TO WESTERN ARKANSAS. THIS WESTWARD PUSH IS PROGGED TO
CONTINUE AND BY 12Z MONDAY IT IS FORECAST TO BE FROM NORTHERN
OKLAHOMA TO NORTHERN TEXAS. IT THEN APPEARS TO REMAIN OVER THE
TEXAS PANHANDLE OR IN NORTHEASTERN NEW MEXICO WHILE GRADUALLY
FILLING INTO THE WORKWEEK.
THIS IS NOT A VERY COMMON SCENARIO AND IF IT DOES COME TO FRUITION
WOULD MEAN COOLER TEMPERATURES STARTING SUNDAY. IN THE PAST 24
HRS...THE EXPECTED 850 MB TEMPS FOR SUNDAY OVER OUR AREA HAVE
DECREASED ABOUT 8-10 DEGREES C. GIVEN THE CONSISTENCY OF THE VARIOUS
OPERATIONAL MODELS WILL BUY INTO THIS SCENARIO AND LOWER HIGHS ON
SUNDAY BY SEVERAL DEGREES. SIMILAR TEMPERATURES CAN BE EXPECTED ON
MONDAY AND TUESDAY. WHILE COOLER THAN THOSE EXPECTED FOR TODAY AND
SATURDAY...WOULD NOT EXACTLY CALL IT COOL WEATHER AS HIGHS WILL
ACTUALLY BE AROUND NORMAL FOR THIS TIME OF YEAR FOR SUN-TUES. AFTER
THAT WE SHOULD SEE A GRADUAL WARMUP AS RIDGE RE-ESTABLISHES ITSELF
OVER THE REGION.
PRECIPITATION CONTINUES TO BE DIFFICULT TO FORECAST. LOOKS LIKE
THERE ARE AT LEAST SLIGHT CHANCES ON SAT AND SUNDAY NIGHTS OVER MUCH
OF THE CWA WITH A SURFACE BOUNDARY JUST TO OUR WEST...WEAK WAVES
ROTATING JUST TO OUR NORTH ALONG THE NORTHERN JET...AND THE
APPROACHING RETROGRADING LOW MENTIONED ABOVE. WILL CONTINUE TO
FORECAST DRY WEATHER FOR THE UPCOMING WORKWEEK BUT THAT MAY CHANGE
DEPENDING HOW FAR NORTH THAT RETROGRADING LOW TRACKS. AT
PRESENT...IT MAY AFFECT THE KANSAS PART OF OUR CWA BUT THE FURTHER
NORTH ITS TRACK...THE BETTER THE CHANCE FOR SOME RAIN IN THE NEB
PART OF OUR CWA.
&&
.AVIATION...(FOR THE 12Z KGRI TAF THROUGH 12Z SATURDAY MORNING)
ISSUED AT 630 AM CDT FRI JUL 12 2013
THERE IS FAIRLY HIGH CONFIDENCE THAT VFR CEILING/VISIBILITY WILL
PREVAIL THROUGH THE PERIOD...WITH MID/UPPER LEVEL HIGH PRESSURE
DOMINATING THE LOCAL WEATHER PATTERN AND PROVIDING MOSTLY CLEAR
SKIES...AND VERY LITTLE IF ANY RISK OF A SHOWER/THUNDERSTORM. AS
FOR SURFACE WINDS...A RATHER CONSTANT SOUTH-SOUTHEAST DIRECTION
WILL PREVAIL THROUGHOUT THE PERIOD...AND IT WILL REMAIN FAIRLY
BREEZY MOST OF THE TIME...WITH GUSTS COMMONLY UP TO AROUND
18KT...AND DAYTIME GUST POTENTIAL TO AT LEAST 25KT. THE ONLY REAL
ISSUE OF NOTE IS LOW LEVEL WIND SHEAR UNDERNEATH A NOCTURNAL LOW
LEVEL JET. WILL CONTINUE A MENTION OF MARGINAL LLWS FOR THE FIRST
FEW HOURS THIS MORNING...AND THEN BRING BACK ANOTHER ROUND OF LLWS
FOR THE EARLY SATURDAY MORNING HOURS THANKS TO A SIMILAR
SETUP...WITH 30+KT OF BULK SHEAR DIFFERENCE BETWEEN THE SURFACE
AND APPROXIMATELY 1500 FT AGL...WHERE SUSTAINED SOUTH-SOUTHWEST
WINDS UP TO AROUND 43KT WILL DEVELOP.
&&
.FIRE WEATHER...
ISSUED AT 431 AM CDT FRI JUL 12 2013
ALTHOUGH CRITICAL FIRE WEATHER CONDITIONS/DANGER ARE NOT
ANTICIPATED WITHIN THE CWA TODAY...NEAR-CRITICAL CONDITIONS ARE
FORECAST ESPECIALLY IN THE FAR SOUTHWEST IN THE PHILLIPS/ROOKS
COUNTY AREAS...AND THUS WILL INTRODUCE THIS MENTION INTO THE
HAZARDOUS WEATHER OUTLOOK. THIS AREA WILL FEATURE THE GREATEST
OVERLAP OF SUSTAINED WINDS/GUSTS 20/25 MPH...AND RELATIVE HUMIDITY
VALUES NEAR OR SLIGHTLY BELOW 25 PERCENT. CERTAINLY...AT LEAST A
LIMITED FIRE DANGER WILL EXIST ELSEWHERE ACROSS THE CWA GIVEN THE
STEADY BREEZES AND OVERALL DRY CONDITIONS OF LATE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...PFANNKUCH
SHORT TERM...PFANNKUCH
LONG TERM...EWALD
AVIATION...PFANNKUCH
FIRE WEATHER...PFANNKUCH
AREA FORECAST DISCUSSION
NWS HASTINGS NE
636 AM CDT FRI JUL 12 2013
.UPDATE...
ISSUED AT 635 AM CDT FRI JUL 12 2013
THE NARROW LINE OF ACCAS-INDUCED SHOWERS THAT EARLIER FLIRTED WITH
THE EASTERN FRINGES OF THE CWA AS SINCE ADVECTED 1+ COUNTY EAST OF
OUR AREA PER THE LATEST RADAR/SATELLITE TRENDS. THUS WILL FORGE
AHEAD WITH NO PRECIP MENTION WHATSOEVER THROUGH THE NEXT 24 HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 431 AM CDT FRI JUL 12 2013
THE PRIMARY ISSUE DURING THE NEXT 24 HOURS IS DETERMINING HOW HOT
WE ACTUALLY GET TODAY/HOW CLOSE WE GET TO HEAT ADVISORY
CRITERIA...AND HOW CLOSE TO CRITICAL FIRE DANGER WESTERN PARTS OF
NORTH CENTRAL KANSAS MIGHT GET. ALTHOUGH THE FORECAST PRODUCTS
CARRY NO MENTION OF SHOWERS/THUNDERSTORMS DUE TO POPS HOLDING BELOW
15 PERCENT...POPS ARE NOT NECESSARILY ZERO...AND WILL HAVE TO KEEP
AN EYE ESPECIALLY ON FAR WESTERN/NORTHERN COUNTIES LATE THIS
AFTERNOON-TONIGHT FOR THE REMOTE CHANCE THAT A FEW STORMS COULD
POP UP OR MOVE IN FROM THE WEST/NORTH. IN THE IMMEDIATE NEXT FEW
HOURS...ITS NOT COMPLETELY OUT OF THE QUESTION THAT A FEW HIGH-
BASED SHOWERS/STORMS COULD TRY DEVELOPING IN EASTERN ZONES BEFORE
SUNRISE.
08Z OBJECTIVE SURFACE ANALYSIS REVEALS A FAIRLY ILL-DEFINED QUASI-
STATIONARY FRONT SNAKING FROM A 1000 MILLIBAR LOW IN NORTHWEST
SD...SOUTHWARD THROUGH WESTERN NEBRASKA INTO NORTHWEST/SOUTH CENTRAL
KS. OFF TO THE EAST...A 1019MB HIGH IS CENTERED NEAR THE IA/IL
BORDER. BETWEEN THE FRONT AND THE HIGH...FAIRLY STEADY SOUTH-
SOUTHEAST BREEZES OF 8-15 MPH WITH OCCASIONAL GUSTS OVER 20 ARE IN
PLACE ACROSS THE CWA EARLY THIS MORNING...WITH THESE BREEZES
EXPECTED TO HELP HOLD LOW TEMPS UP BETWEEN 69-74 IN MOST AREAS.
ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA HIGHLIGHT A
FAIRLY EXPANSIVE MID/UPPER LEVEL RIDGE AXIS THAT HAS BUILT
NORTHEAST SINCE 24 HOURS AGO TO ENCOMPASS MUCH OF THE
CENTRAL/SOUTH CENTRAL CONUS. THE CENTER AXIS OF THIS RIDGE...AT
ROUGHLY 590 DECAMETER...RUNS FROM ROUGHLY THE LOCAL CWA ON THE
NORTHEAST EDGE...BACK SOUTHWESTWARD TOWARD THE NM/TX BORDER. WITH
THIS RIDGE AXIS NEARLY OVERHEAD...THE FLOW OVER THE CWA AT 500MB
IS FAIRLY LIGHT/VARIABLE...WHILE A BIT LOWER AT 700MB...THERE IS
MODEST WEST-SOUTHWEST FLOW. A NARROW ZONE OF THETA-E ADVECTION
ALONG A FAIRLY TIGHT 700MB MOISTURE GRADIENT HAS RESULTED IN A
SCATTERED ACCAS FIELD WITHIN ROUGHLY THE EASTERN 1/3 OF THE CWA
TONIGHT...AND RECENTLY THE FIRST FEW HINTS OF ISOLATED ELEVATED
SPRINKLES/LIGHT SHOWERS HAVE SHOWED UP ON RADAR WITHIN A FEW OF
OUR EASTERN COUNTIES.
STARTING WITH THE MOST IMMEDIATE ISSUE...WILL BE CLOSELY
MONITORING RADAR TRENDS IN EASTERN ZONES PRIOR TO SUNRISE TO SEE
WHETHER THE AFOREMENTIONED VERY ISOLATED CONVECTION CAN BE COVERED
WITH A SPRINKLE MENTION...OR MIGHT NEED SOMETHING MORE.
THE LATEST RAP HAS CAUGHT ONTO THIS DEVELOPMENT...AND SUGGESTS
THAT MAINLY OUR FAR EASTERN COUNTIES NEAR THE HWY 81 CORRIDOR
COULD CONTINUE TO SEE SOME OF THIS PRE-DAWN ACTIVITY...BUT THAT IT
SHOULD LARGELY BE DONE OR ADVECTED EAST OF THE CWA BY 7AM/12Z. PER
FORECAST SOUNDINGS...PARCELS ROOTED NEAR 700MB COULD POTENTIALLY
HAVE UP TO AROUND 400 J/KG MUCAPE AVAILABLE TO THEM...SO A BRIEF
FLARE UP OF NON-SEVERE THUNDERSTORMS IS NOT COMPLETELY OUT OF THE
QUESTION. FOR NOW...WILL ONLY MENTION ISOLATED SPRINKLES IN OUR
EASTERN FEW COLUMNS OF NEBRASKA COUNTIES THROUGH 12Z TO COVER
THINGS...PENDING ANY EVIDENCE OTHERWISE.
TURNING TO THE DAYTIME HOURS...THE MAIN STORY WILL BE A RETURN OF
LEGITIMATE SUMMER HEAT...BUT DOES NOT APPEAR TO BE HEADLINE-
WORTHY. IN THE MID/UPPER LEVELS...THE DOMINANT RIDGE AXIS WILL
CONTINUE TO EXPAND ACROSS THE CENTRAL PLAINS IN A SOUTHWEST-
NORTHEAST FASHION...WITH PARTS OF THE CWA ALIGNED ALMOST DIRECTLY
UNDER ITS CENTER AXIS. AT THE SURFACE...A FAIRLY SHARP TROUGH
AXIS WILL SET UP FROM FAR EASTERN CO ACROSS NORTHWEST NEB INTO
CENTRAL SD BY MID-LATE AFTERNOON...EXTENDING FROM A ROUGHLY 1000MB
LOW CENTERED NEAR THE CO/KS BORDER. THE LOCAL CWA WILL REMAIN IN
THE OPEN WARM SECTOR SOLIDLY SOUTHEAST OF THIS TROUGH AXIS...AND
THUS WILL SEE A CONTINUATION OF FAIRLY BREEZY SOUTH-SOUTHEAST
WINDS...WITH SUSTAINED SPEEDS MOST ALL AREAS 15-20 MPH AND GUSTS
25 TO POSSIBLY 30 MPH AT TIMES. AS FOR CONVECTIVE CHANCES...ASIDE
FROM ANY EARLY MORNING ACTIVITY IN THE EAST...THERE IS LITTLE IF
ANY RISK OF SHOWERS/STORMS TODAY AS WARM MID LEVEL TEMPS WITHIN
THE RIDGE AXIS SHOULD SERVE TO CAP THINGS OFF PRETTY SOLIDLY. ONE
OF THE ONLY POSSIBLE CAVEATS...AS DEPICTED BY THE LATEST RAP
RUNS...IS THAT STRONG HEATING AND VERY DEEP MIXING COULD POP A FEW
HIGH-BASED STORMS LATE IN THE AFTERNOON ALONG WESTERN PORTIONS OF
THE NEB/KS BORDER...WITH SOME OF THIS ACTIVITY POSSIBLY ADVECTING
EAST INTO THE DAWSON-FURNAS COUNTY CORRIDOR...BUT THE ODDS OF THIS
SEEM LOW ENOUGH TO STICK WITH SILENT 10 POPS FOR NOW...AS MOST
LATE AFTERNOON STORMS SHOULD FOCUS WELL TO OUR NORTHWEST ALONG THE
AFOREMENTIONED TROUGH AXIS. TEMP-WISE...BASED ON HOW HIGHS TURNED
OUT YESTERDAY...IT APPEARS THE NAM AND ASSOCIATED MET GUIDANCE HAS
BEEN A BIT AGGRESSIVE WITH THE HEAT...AND AS A RESULT...HAVE
SHAVED A FEW DEGREES OFF HIGHS TODAY IN MOST AREAS...USING VALUES
A BIT CLOSER TO GFS MAV GUIDANCE AND A MULTI-MODEL BLEND. THIS STILL
YIELDS A VERY TOASTY DAY WITH HIGHS RANGING FROM MID 90S NORTHEAST
...MID-UPPER 90S CENTRAL AND UPPER 90S TO AROUND 102 IN KS ZONES
AND NEAR THE STATE LINE. AS FOR DEWPOINTS...NOT EXPECTING A
DRAMATIC MIX-DOWN TODAY GIVEN THAT WINDS WILL BE MORE SOUTHERLY
VERSUS SOUTHWESTERLY...BUT NUDGED THEM DOWN A BIT ESPECIALLY IN
WESTERN ZONES...RANGING FROM UPPER 50S AT MID-AFTERNOON IN THE FAR
WEST TO MID-UPPER 60S IN THE EAST. THE RESULTANT HEAT INDEX VALUES
PEAK IN THE 98-100 RANGE ACROSS MOST OF THE NEB CWA...WITH KS
ZONES AND AREAS NEAR THE STATE LINE MORE LIKELY TO REACH THE
101-104 RANGE. BOTTOM LINE HERE IS...THESE VALUES ARE CERTAINLY
WORTH A HAZARDOUS WEATHER OUTLOOK MENTION...BUT DO NOT JUSTIFY A
FORMAL HEAT ADVISORY BASED ON OUR 105+ LOCAL CRITERIA. PLEASE NOTE
THAT THE NORTH PLATTE/LBF CWA HAS A SLIGHTLY COOLER
...CLIMATOLOGICALLY-BASED HEAT ADVISORY CRITERIA OF 100+...AND
THIS IS WHY A FORMAL HEADLINE IS OUT FOR THEIR AREA...BUT NOT FOR
OURS.
TURNING TO THIS EVENING/TONIGHT POST-7PM/00Z...THE MAIN STORY
VERSUS PREVIOUS FORECAST IS THAT THE SLIGHT CHANCE OF
THUNDERSTORMS HAS BEEN TRIMMED FROM THE EXTREME NORTHERN/WEST-
CENTRAL EDGES OF THE CWA...AND THUS WILL CARRY A STORM-FREE
FORECAST CWA-WIDE. AGAIN THOUGH...WILL EMPHASIZE THAT SILENT 10
POPS WILL REMAIN IN PLACE ESPECIALLY IN NORTHERN/WESTERN COUNTIES
TO AT LEAST ACKNOWLEDGE THAT A VERY LOW PROBABILITY OF SOME
ACTIVITY IS NOT COMPLETELY OUT OF THE QUESTION. IN THE MID-UPPER
LEVELS...THERE IS VERY LITTLE CHANGE WITH THE STRENGTH/ORIENTATION
OF THE EXPANSIVE RIDGE AXIS...AS IT REMAINS DRAPED FROM SOUTHWEST-
NORTHEAST ACROSS THE HEART OF THE CENTRAL PLAINS. A BIT LOWER AT
850MB...A 40+KT SOUTHERLY LOW LEVEL JET CRANKS UP THROUGH THE
NIGHT FROM WESTERN KS ACROSS CENTRAL NEB INTO EASTERN SD/WESTERN
MN...HELPING TO FOCUS THE VAST MAJORITY OF REGIONAL CONVECTION
NEAR THE EXIT REGION OF THIS FEATURE FROM NORTHEAST CO ACROSS
NORTHWEST NEB INTO SD/MN. AT THE SURFACE...THERE WILL ALSO BE
LITTLE OVERALL CHANGE FROM THE DAYTIME HOURS...WITH THE TROUGH
AXIS PERSISTING FROM NEAR THE KS/CO BORDER NORTH-NORTHEAST INTO
CENTRAL SD. WITH A CONTINUED MODEST PRESSURE GRADIENT AND LIMITED
MIXING UNDER THE LOW LEVEL JET...SURFACE BREEZES ACROSS THE CWA
WILL AGAIN AVERAGE 10-15 MPH FROM THE SOUTH-SOUTHEAST. ASSUMING
THAT POTENTIALLY ROGUE LATE AFTERNOON/EARLY EVENING STORMS DO NOT
AFFECT THE FAR WESTERN CWA...ITS PRETTY APPARENT FROM MOST MODEL
DEPICTIONS THAT OVERNIGHT CONVECTION SHOULD FOCUS AT LEAST 50-100
MILES NORTH THROUGH NORTHWEST OF THE CWA...AND GENERALLY LIFT
NORTH WITH TIME. THE ONLY FORESEEABLE CAVEAT HERE WOULD BE IF
NORTHERN NEB STORMS DEVELOP A COLD POOL AND START TO BUILD
SOUTHWARD INTO THE LOW LEVEL JET AXIS...POTENTIALLY REACHING THE
NORTHERN PARTS OF THE CWA. INTERESTINGLY...AT LEAST ONE
MODEL...THE 4KM WRF-NMM FROM PSU...DOES DEPICT THIS SCENARIO...BUT
GIVEN SUCH LIMITED SUPPORT WILL KEEP IT STORM-FREE FOR NOW. WILL
ALSO NOTE THAT THE 00Z GFS DEPICTION OF LATE NIGHT STORMS FLARING
UP NEAR HIGHWAY 81...LIKELY IN RESPONSE TO ANOTHER SUBTLE BATCH OF
MID LEVEL THETA-E ADVECTION...HAS BEEN DISREGARDED AS AN OUTLIER
AS WELL FOR THIS FORECAST. LOW TEMPERATURES WERE CHANGED
LITTLE...AND AGAIN REFLECT A SLIGHT UPWARD TREND FROM THE PAST FEW
NIGHTS...WITH MOST AREAS PROGGED TO BOTTOM OUT 72-75.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 431 AM CDT FRI JUL 12 2013
FOCUS FOR THIS TIMEFRAME WILL INVOLVE BOTH HIGH TEMPERATURES AND
PRECIPITATION CHANCES. MOST OF THE OPERATIONAL MODELS ARE COMING
INTO AGREEMENT ON THE UNUSUAL PATTERN EXPECTED IN THE SATURDAY TO
THURSDAY PERIOD. THEY ARE TAKING THE MID/UPPER LEVEL LOW PRESSURE
CURRENTLY SITTING OVER OHIO...AND RETROGRADING IT BACK TO THE
WEST. BY 12Z SAT THE GFS HAS IT OVER CENTRAL TENN...WHILE THE EC
PLACES IT A LITTLE NORTH OF THERE OVER KENTUCKY...AND THE NAM IS
BETWEEN THE TWO. BY 12Z SUNDAY THESE MODELS HAVE IT FROM CENTRAL
MISSOURI TO WESTERN ARKANSAS. THIS WESTWARD PUSH IS PROGGED TO
CONTINUE AND BY 12Z MONDAY IT IS FORECAST TO BE FROM NORTHERN
OKLAHOMA TO NORTHERN TEXAS. IT THEN APPEARS TO REMAIN OVER THE
TEXAS PANHANDLE OR IN NORTHEASTERN NEW MEXICO WHILE GRADUALLY
FILLING INTO THE WORKWEEK.
THIS IS NOT A VERY COMMON SCENARIO AND IF IT DOES COME TO FRUITION
WOULD MEAN COOLER TEMPERATURES STARTING SUNDAY. IN THE PAST 24
HRS...THE EXPECTED 850 MB TEMPS FOR SUNDAY OVER OUR AREA HAVE
DECREASED ABOUT 8-10 DEGREES C. GIVEN THE CONSISTENCY OF THE VARIOUS
OPERATIONAL MODELS WILL BUY INTO THIS SCENARIO AND LOWER HIGHS ON
SUNDAY BY SEVERAL DEGREES. SIMILAR TEMPERATURES CAN BE EXPECTED ON
MONDAY AND TUESDAY. WHILE COOLER THAN THOSE EXPECTED FOR TODAY AND
SATURDAY...WOULD NOT EXACTLY CALL IT COOL WEATHER AS HIGHS WILL
ACTUALLY BE AROUND NORMAL FOR THIS TIME OF YEAR FOR SUN-TUES. AFTER
THAT WE SHOULD SEE A GRADUAL WARMUP AS RIDGE RE-ESTABLISHES ITSELF
OVER THE REGION.
PRECIPITATION CONTINUES TO BE DIFFICULT TO FORECAST. LOOKS LIKE
THERE ARE AT LEAST SLIGHT CHANCES ON SAT AND SUNDAY NIGHTS OVER MUCH
OF THE CWA WITH A SURFACE BOUNDARY JUST TO OUR WEST...WEAK WAVES
ROTATING JUST TO OUR NORTH ALONG THE NORTHERN JET...AND THE
APPROACHING RETROGRADING LOW MENTIONED ABOVE. WILL CONTINUE TO
FORECAST DRY WEATHER FOR THE UPCOMING WORKWEEK BUT THAT MAY CHANGE
DEPENDING HOW FAR NORTH THAT RETROGRADING LOW TRACKS. AT
PRESENT...IT MAY AFFECT THE KANSAS PART OF OUR CWA BUT THE FURTHER
NORTH ITS TRACK...THE BETTER THE CHANCE FOR SOME RAIN IN THE NEB
PART OF OUR CWA.
&&
.AVIATION...(FOR THE 12Z KGRI TAF THROUGH 12Z SATURDAY MORNING)
ISSUED AT 630 AM CDT FRI JUL 12 2013
THERE IS FAIRLY HIGH CONFIDENCE THAT VFR CEILING/VISIBILITY WILL
PREVAIL THROUGH THE PERIOD...WITH MID/UPPER LEVEL HIGH PRESSURE
DOMINATING THE LOCAL WEATHER PATTERN AND PROVIDING MOSTLY CLEAR
SKIES...AND VERY LITTLE IF ANY RISK OF A SHOWER/THUNDERSTORM. AS
FOR SURFACE WINDS...A RATHER CONSTANT SOUTH-SOUTHEAST DIRECTION
WILL PREVAIL THROUGHOUT THE PERIOD...AND IT WILL REMAIN FAIRLY
BREEZY MOST OF THE TIME...WITH GUSTS COMMONLY UP TO AROUND
18KT...AND DAYTIME GUST POTENTIAL TO AT LEAST 25KT. THE ONLY REAL
ISSUE OF NOTE IS LOW LEVEL WIND SHEAR UNDERNEATH A NOCTURNAL LOW
LEVEL JET. WILL CONTINUE A MENTION OF MARGINAL LLWS FOR THE FIRST
FEW HOURS THIS MORNING...AND THEN BRING BACK ANOTHER ROUND OF LLWS
FOR THE EARLY SATURDAY MORNING HOURS THANKS TO A SIMILAR
SETUP...WITH 30+KT OF BULK SHEAR DIFFERENCE BETWEEN THE SURFACE
AND APPROXIMATELY 1500 FT AGL...WHERE SUSTAINED SOUTH-SOUTHWEST
WINDS UP TO AROUND 43KT WILL DEVELOP.
&&
.FIRE WEATHER...
ISSUED AT 431 AM CDT FRI JUL 12 2013
ALTHOUGH CRITICAL FIRE WEATHER CONDITIONS/DANGER ARE NOT
ANTICIPATED WITHIN THE CWA TODAY...NEAR-CRITICAL CONDITIONS ARE
FORECAST ESPECIALLY IN THE FAR SOUTHWEST IN THE PHILLIPS/ROOKS
COUNTY AREAS...AND THUS WILL INTRODUCE THIS MENTION INTO THE
HAZARDOUS WEATHER OUTLOOK. THIS AREA WILL FEATURE THE GREATEST
OVERLAP OF SUSTAINED WINDS/GUSTS 20/25 MPH...AND RELATIVE HUMIDITY
VALUES NEAR OR SLIGHTLY BELOW 25 PERCENT. CERTAINLY...AT LEAST A
LIMITED FIRE DANGER WILL EXIST ELSEWHERE ACROSS THE CWA GIVEN THE
STEADY BREEZES AND OVERALL DRY CONDITIONS OF LATE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...PFANNKUCH
SHORT TERM...PFANNKUCH
LONG TERM...EWALD
AVIATION...PFANNKUCH
FIRE WEATHER...PFANNKUCH
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
948 AM EDT FRI JUL 12 2013
.SYNOPSIS...
A COLD FRONT WILL SLOWLY MOVE IN FROM THE NORTHWEST TONIGHT AND
BECOME STATIONARY OVER EASTERN NORTH CAROLINA. THE FRONT WILL
DISSIPATE ON SUNDAY. A TROF OF LOW PRESSURE WILL PASS THROUGH
FROM THE EAST ON MONDAY. A TROF OF LOW PRESSURE WILL DEVELOP ALONG
THE COASTAL PLAIN WEDNESDAY AND CONTINUE INTO THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 945 AM FRI...AREA OF MODERATE TO HEAVY RAIN W/EMBEDDED THUNDER
OVER SOUTHEAST NC AND ADJACENT WATERS IS MOVING NORTHEAST AND WILL
AFFECT THE FORECAST AREA IN THE NEXT FEW HOURS. RUC HOURLY
ANALYSIS SHOWS THIS AREA BEING DRIVEN BY A WELL-DEFINED VORT LOBE
OVER SE NC/NE SC. AREA ALSO UNDERNEATH RIGHT REAR QUAD OF UPPER
JET. WILL MAINTAIN LIKELY TO CATEGORICAL POPS THROUGH TODAY. TEMPS
WILL ONLY REACH THE LOW 80S DUE TO THE WIDESPREAD CLOUDS/PRECIP.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
AS OF 330 AM FRI...CONTINUING WET WEATHER FOR THIS EVENING... WITH
BEST PRECIP CHANCES TRANSITIONING TO THE COAST FOR THE OVERNIGHT.
QPF AMOUNTS LOOK TO BE LOWER AS BEST UPPER FORCING RETREATS AWAY
FROM THE REGION. WILL KEEP HEAVY RAIN MENTION OUT OF GRIDS THOUGH
WITH ANY EMBEDDED THUNDERSTORMS SOME AREAS WILL RECEIVE LOCALLY
HEAVIER RAIN.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 230 AM FRI...DEEP MOISTURE WILL CONT OVER THE REGION EARLY
SAT WITH HIGH CHC TO LIKELY POPS ALL AREAS. LATER SAT THE UPR LOW
TO THE W WILL CONT TO SHIFT FURTHER W AND DRIER AIR WILL BEGIN TO
WORK IN ESPCLY ALONG THE CST AND EXPECT PRECIP TO DIMINISH FOR ALL
BUT DEEP INLAND AREAS. RIDGE WILL THEN GRAD BUILD IN FROM THE NNE
SUN INTO EARLY NEXT WEEK WITH MAINLY DIURNAL PRECIP WITH BEST CHCS
INLAND DURING AFTN AND EVENING.
MID TO LATE WEEK THE UPR RDG WILL BUILD TO OUR WEST WITH PRECIP
CONFINED MAINLY TO THE SEA BRZ DURING THE AFTN AND EVENING INLAND.
TEMPS WILL HOLD IN THE 80S SAT THEN WITH MORE SUN REACH AROUND 90
INLAND SUN AND MON WITH LOWER 90S TUE THRU THU. MUGGY LOWS MAINLY
IN THE 70S WILL PERSIST.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
SHORT TERM /TODAY AND TONIGHT/
AS OF 945 AM FRI...PERIODS OF RAIN AND OCNL THUNDER EXPECTED THROUGH
THE TAF PERIOD. CIGS WILL GENERALLY BE MVFR THOUGH WITH HEAVY
SHOWERS DIP DOWN TO IFR ALONG WITH LOWERED VSBYS. WINDS WILL BE
LIGHT FOR THIS TAF PERIOD.
LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 215 AM FRI...DECENT CVRG OF SHRA AND TSRA SAT ESPCLY EARLY
WITH SUB VFR LIKELY AT TIMES. MAINLY VFR DURING THE DAY AND
EVENING HOURS FROM SAT NIGHT ON AS RDG BUILDS TO THE N WITH DRIER
AIR SPREADING OVER THE REGION. AS USUAL WITH MOIST LOW LVL AND
RATHER LIGHT WINDS WILL LIKELY HAVE TYPICAL LATE NIGHT EARLY MORN
FOG AND STRATUS WITH AREAS OF REDUCED CIGS AND VSBYS AT TIMES.
&&
.MARINE...
SHORT TERM /TODAY AND TONIGHT/
AS OF 945 AM FRI...PRESENTLY WINDS ARE S TO SW 10 KNOTS OR LESS
ACROSS THE MARINE AREA. EXPECT WINDS TO INCREASE THIS AFTERNOON TO
CURRENTLY FORECAST LEVELS...SO DO NOT PLAN ANY CHANGES TO CURRENT
ZONES. WINDS WILL BACK SOUTH AND THEN SE TONIGHT AS HIGH PRES
BEGINS TO INFLUENCE THE COASTAL WATERS FROM THE NORTHEAST.
LONG TERM /SAT THROUGH TUESDAY/...
AS OF 215 AM FRI...MDLS SIMILAR SAT SHOWING DECENT GRDNT OVER AREA
BETWEEN HIGH TO THE N AND LOW TO THE SW. EXPECT SSE WINDS 15 TO 20
KTS AND SEAS 4 TO 6 FEET...HIGHEST OUTER CNTRL/SRN WATERS. AS THE
HIGH GRAD BUILDS SOUTH TWRD THE REGION SUN WINDS WILL BECOME E
LESS THAN 15 KTS WITH SEAS SUBSIDING TO 2 TO 3 FEET BY LATE
SUNDAY. THE HIGH WILL REMAIN NEAR THE AREA MON AND TUE WITH LIGHT
WINDS AND SEAS MAINLY 2 TOM 3 FEET...WITH POSS SOME 4 FOOTERS
OUTER WTRS MON.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR NCZ029-044>047-
079>081-090>095-098-103-104.
MARINE...NONE.
&&
$$
SYNOPSIS...TL
NEAR TERM...HSA/TL
SHORT TERM...TL
LONG TERM...RF
AVIATION...HSA/TL/RF
MARINE...HSA/TL/RF
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
940 AM CDT FRI JUL 12 2013
.UPDATE...
ISSUED AT 940 AM CDT FRI JUL 12 2013
BUMPED UP POPS IN OUR NORTHEASTERN COUNTIES AS THERE HAS BEEN SOME
CONVECTIVE DEVELOPMENT ALONG THE NOSE OF THE 850MB WARM AIR
ADVECTION. THINK THAT THIS WILL TRANSITION NORTHEASTWARD BY THIS
AFTERNOON AND THEN THE FOCUS OF CONVECTION WILL BE THE COLD FRONT
MOVING INTO THE CENTRAL CWA. ALSO BUMPED UP HIGHS A TAD IN OUR
SOUTHERN COUNTIES AS MANY GUIDANCE VALUES HAVE THAT AREA GETTING
INTO THE 90S. THE RAP AND HRRR HAVE THE SOUTH CLIMBING INTO THE
100S THIS AFTERNOON BUT THAT SEEMS EXTREME GIVEN THE HIGH DEW
POINTS IN THE AREA.
UPDATE ISSUED AT 713 AM CDT FRI JUL 12 2013
AT 12Z... A QUASI STATIONARY FRONTAL SYSTEM STRETCHED FROM A LOW
PRESSURE CENTER IN WESTERN SD... THROUGH CENTRAL ND AND UP INTO A
LOW PRESSURE CENTER IN NRN MAN. WAVES OF SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS WERE PROPAGATING NORTHEASTWARD AHEAD OF
THIS FRONT... WITH ONE AREA PUSHING OUT OF THE NRN RED RIVER
VALLEY AS A SECOND AREA WAS MOVING THROUGH THE BISMARCK AREA AND
ARCING TOWARDS TEH DEVILS LAKE BASIN.
THESE SHOWERS LOOK TO PERSIST INTO THE THE LATE FORENOON... UNTIL
LOW LEVEL JET STRENGTH DIMINISHES. 06Z NAM40 GUIDANCE SUGGESTS
THAT BLAYER WARMING THROUGH THE FORENOON AND EARLY AFTERNOON
/AHEAD OF THE FRONT/ SHOULD PRODUCE MIXED LAYER CAPE VALUES OF
2000 J/KG OR GREATER BY 21Z... WHILE COOLING H7 TEMPS SHOULD ALLOW
FOR ONSET OF DEEP CONVECTION AS PER PREVIOUS DISCUSSION.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 355 AM CDT FRI JUL 12 2013
FORECAST CHALLENGE WILL BE THE EXTENT AND DURATION OF SHOWERS AND
THUNDERSTORMS THROUGH THIS MORNING... THEN TIMING OF REDEVELOPMENT
LATER TODAY AND TONIGHT.
FOR NOW... LOW LEVEL MOISTURE TRANSPORT APPEARS TO HAVE SURGED IN
THE LAST COUPLE OF HOURS LEADING TO INCREASED DEEP CONVECTION ACROSS
NCNTRL AND FAR NERN ND... AHEAD OF A WEAK SFC COLD FRONT. THIS
AREA SHOWS 1500-2000 J/KG OF CAPE AND PWATS IN EXCESS OF 1.5
INCHES AT 08Z ANALYSIS... WITH 40KM RAP AND NAM GUIDANCE LIFTING
THIS AREA THROUGH FAR NERN ND INTO SRN MAN THROHGH 15Z. EXPECT
SOME BREAK IN THE ACTIVITY THROUGH MIDDAY WITH SERN ND AND WCNTRL
MN LIKELY TO HEAT OUT QUICKLY AND REACH CONVECTIVE TEMPS BY
MIDAFTERNOON.
NAM DEPICTION SEEMS REASONABLE THROUGH TODAY AND INTO THE EARLY
PORTION OF THE WEEKEND... SHOWING THE SFC FRONT SLOWLY SAGGING
INTO THE SOUTHERN FA BY TONIGHT AND STALLING THERE THROUGH SUNDAY
MORNING. LATE THIS AFTERNOON INTO EARLY SATURDAY MORNING EXPECT
THE FOCUS FOR DEEP CONVECTION TO SHIFT ACROSS THE SOUTHERN FA...
WITH PERIODS OF STRONG TO SEVERE THUNDERSTORMS POSSIBLE ALONG WITH
BRIEF HEAVY RAINS. CONVECTIVE INHIBITION SHUD BREAK DOWN FAIRLY
QUICKLY THROUGH MID AFTERNOON AS COOLER H7 TEMPS MOVE OVHD... WITH
SOME THREAT FOR ISOLD TORNADIC SUPERCELLS TO DEVELOP IN THE LATE
AFTERNOON...THROUGH CENTRAL PORTIONS OF THE RRV.
OVERNIGHT TONIGHT THROUGH SATURDAY... FOCUS WILL SWITCH TO HEAVIER
RAIN PRODUCING CONVECTIVE CLUSTERS ACROSS THE SOUTHERN HALF OF THE
THE RRV.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
SATURDAY NIGHT THROUGH SUNDAY... SOME BREAK IN THE THUNDERSTORM
ACTIVITY IS EXPECTED TO DEVELOP FROM NORTHWEST TO SOUTHEAST ON
SATURDAY. DEEP MOIST AND UNSTABLE FLOW SHUD RETURN TO TEH AREA ON
SUNDAY.
MONDAY THROUGH THURSDAY... LONG WAVE UPPER LEVEL RIDGE REMAINS
PARKED OVER CO THIS PERIOD. LONG WAVE TROUGH OVER WESTERN CANADA
SWEEPS INTO EASTERN CANADA BY THE END OF THE PERIOD. FLOW ALOFT
BECOMES NORTHWEST ALOFT OVER CANADA AND THE FAR NORTHERN PLAINS. A
FRONTAL BOUNDARY MOVES INTO THE AREA TUE OR WED. WILL BLEND THE
ECMWF AND GFS.
NORTHWEST FLOW ALOFT BECOMES ESTABLISHED OVER CANADA AND THE
NORTHERN STATES THIS PERIOD. GFS AND ECMWF WERE VACILLATING OVER
SOUTHERN CANADA AND FAR NORTHERN ZONES TUE. SO WILL REMOVE
PRECIPITATION FROM TUE AND TRIM BACK TUE NIGHT PRECIP FARTHER NORTH.
WILL KEEP YESTERDAYS POPS FOR WED NIGHT.
HIGH TEMPS INCREASED COUPLE DEGREES IN THE NORTHWEST ZONES TUE FROM
YESTERDAYS RUN. BOTH HIGH AND LOW TEMPS DECREASED ABOUT A DEGREE OR
TWO FOR WED AND THU.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 715 AM CDT FRI JUL 12 2013
EXPECT MAINLY VFR CIGS AND VSBYS THROUGH THIS MORNING ACROSS THE FA...
WITH SCT SHOWERS AND AN ISOLD TSTM ALONG AND NEAR A BIS-DVL-ROX
LINE. BY MID AFTERNOON EXPECT SCT STRONG TO SEVERE TSMS TO DEVELOP
JUST EASTWARD OF THIS LINE... AND TO PROGRESS STEADILY EASTWARD
THROUGH EARLY EVENING.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...GUST
LONG TERM...HOPPES
AVIATION...GUST
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
717 AM CDT FRI JUL 12 2013
.UPDATE...
ISSUED AT 713 AM CDT FRI JUL 12 2013
AT 12Z... A QUASI STATIONARY FRONTAL SYSTEM STRETCHED FROM A LOW
PRESSURE CENTER IN WESTERN SD... THROUGH CENTRAL ND AND UP INTO A
LOW PRESSURE CENTER IN NRN MAN. WAVES OF SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS WERE PROPAGATING NORTHEASTWARD AHEAD OF
THIS FRONT... WITH ONE AREA PUSHING OUT OF THE NRN RED RIVER
VALLEY AS A SECOND AREA WAS MOVING THROUGH THE BISMARCK AREA AND
ARCING TOWARDS TEH DEVILS LAKE BASIN.
THESE SHOWERS LOOK TO PERSIST INTO THE THE LATE FORENOON... UNTIL
LOW LEVEL JET STRENGTH DIMINISHES. 06Z NAM40 GUIDANCE SUGGESTS
THAT BLAYER WARMING THROUGH THE FORENOON AND EARLY AFTERNOON
/AHEAD OF THE FRONT/ SHOULD PRODUCE MIXED LAYER CAPE VALUES OF
2000 J/KG OR GREATER BY 21Z... WHILE COOLING H7 TEMPS SHOULD ALLOW
FOR ONSET OF DEEP CONVECTION AS PER PREVIOUS DISCUSSION.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 355 AM CDT FRI JUL 12 2013
FORECAST CHALLENGE WILL BE THE EXTENT AND DURATION OF SHOWERS AND
THUNDERSTORMS THROUGH THIS MORNING... THEN TIMING OF REDEVELOPMENT
LATER TODAY AND TONIGHT.
FOR NOW... LOW LEVEL MOISTURE TRANSPORT APPEARS TO HAVE SURGED IN
THE LAST COUPLE OF HOURS LEADING TO INCREASED DEEP CONVECTION ACROSS
NCNTRL AND FAR NERN ND... AHEAD OF A WEAK SFC COLD FRONT. THIS
AREA SHOWS 1500-2000 J/KG OF CAPE AND PWATS IN EXCESS OF 1.5
INCHES AT 08Z ANALYSIS... WITH 40KM RAP AND NAM GUIDANCE LIFTING
THIS AREA THROUGH FAR NERN ND INTO SRN MAN THROHGH 15Z. EXPECT
SOME BREAK IN THE ACTIVITY THROUGH MIDDAY WITH SERN ND AND WCNTRL
MN LIKELY TO HEAT OUT QUICKLY AND REACH CONVECTIVE TEMPS BY
MIDAFTERNOON.
NAM DEPICTION SEEMS REASONABLE THROUGH TODAY AND INTO THE EARLY
PORTION OF THE WEEKEND... SHOWING THE SFC FRONT SLOWLY SAGGING
INTO THE SOUTHERN FA BY TONIGHT AND STALLING THERE THROUGH SUNDAY
MORNING. LATE THIS AFTERNOON INTO EARLY SATURDAY MORNING EXPECT
THE FOCUS FOR DEEP CONVECTION TO SHIFT ACROSS THE SOUTHERN FA...
WITH PERIODS OF STRONG TO SEVERE THUNDERSTORMS POSSIBLE ALONG WITH
BRIEF HEAVY RAINS. CONVECTIVE INHIBITION SHUD BREAK DOWN FAIRLY
QUICKLY THROUGH MID AFTERNOON AS COOLER H7 TEMPS MOVE OVHD... WITH
SOME THREAT FOR ISOLD TORNADIC SUPERCELLS TO DEVELOP IN THE LATE
AFTERNOON...THROUGH CENTRAL PORTIONS OF THE RRV.
OVERNIGHT TONIGHT THROUGH SATURDAY... FOCUS WILL SWITCH TO HEAVIER
RAIN PRODUCING CONVECTIVE CLUSTERS ACROSS THE SOUTHERN HALF OF THE
THE RRV.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
SATURDAY NIGHT THROUGH SUNDAY... SOME BREAK IN THE THUNDERSTORM
ACTIVITY IS EXPECTED TO DEVELOP FROM NORTHWEST TO SOUTHEAST ON
SATURDAY. DEEP MOIST AND UNSTABLE FLOW SHUD RETURN TO TEH AREA ON
SUNDAY.
MONDAY THROUGH THURSDAY... LONG WAVE UPPER LEVEL RIDGE REMAINS
PARKED OVER CO THIS PERIOD. LONG WAVE TROUGH OVER WESTERN CANADA
SWEEPS INTO EASTERN CANADA BY THE END OF THE PERIOD. FLOW ALOFT
BECOMES NORTHWEST ALOFT OVER CANADA AND THE FAR NORTHERN PLAINS. A
FRONTAL BOUNDARY MOVES INTO THE AREA TUE OR WED. WILL BLEND THE
ECMWF AND GFS.
NORTHWEST FLOW ALOFT BECOMES ESTABLISHED OVER CANADA AND THE
NORTHERN STATES THIS PERIOD. GFS AND ECMWF WERE VACILLATING OVER
SOUTHERN CANADA AND FAR NORTHERN ZONES TUE. SO WILL REMOVE
PRECIPITATION FROM TUE AND TRIM BACK TUE NIGHT PRECIP FARTHER NORTH.
WILL KEEP YESTERDAYS POPS FOR WED NIGHT.
HIGH TEMPS INCREASED COUPLE DEGREES IN THE NORTHWEST ZONES TUE FROM
YESTERDAYS RUN. BOTH HIGH AND LOW TEMPS DECREASED ABOUT A DEGREE OR
TWO FOR WED AND THU.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 715 AM CDT FRI JUL 12 2013
EXPECT MAINLY VFR CIGS AND VSBYS THROUGH THIS MORNING ACROSS THE FA...
WITH SCT SHOWERS AND AN ISOLD TSTM ALONG AND NEAR A BIS-DVL-ROX
LINE. BY MID AFTERNOON EXPECT SCT STRONG TO SEVERE TSMS TO DEVELOP
JUST EASTWARD OF THIS LINE... AND TO PROGRESS STEADILY EASTWARD
THROUGH EARLY EVENING.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...GUST
SHORT TERM...GUST
LONG TERM...HOPPES
AVIATION...GUST
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
1030 AM EDT FRI JUL 12 2013
.DISCUSSION...
A CLOSED MID/UPPER LEVEL LOW OVER WV IS DRIFTING SOUTHWARD TODAY.
THIS WILL PRODUCE COOLER MIDLEVEL TEMPS AND STEEPER LAPSE RATES
OVER NORTHERN PORTIONS OF THE AREA THIS AFTERNOON. RUC SHOWS
CONVECTIVE INHIBITION IS WEAKEST NORTH...WITH A WEAK INVERSION
REMAINING AT TYS AND CHA. SO THE CURRENT POP FORECAST OF SLIGHT/LOW
CHANCES NORTH AND ALONG THE MOUNTAINS LOOKS ON TRACK. WITH WETB
BULB ZERO HEIGHTS FALLING TO AROUND 10 KFT NORTH...SOME SMALL HAIL
MAY BE POSSIBLE...BUT MEETING SEVERE CRITERIA SEEMS UNLIKELY. TEMPS
APPEAR ON TRACK AS WELL...SO NO UPDATE WILL BE NEEDED.
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1134 AM EDT FRI JUL 12 2013
.SYNOPSIS...
LOW PRESSURE WILL DRIFT INTO WEST VIRGINIA AND STALL...THEN DRIFT
SLOWLY BACK WEST INTO THE TENNESSEE VALLEY THROUGH EARLY NEXT
WEEK. MEANWHILE...HIGH PRESSURE ALOFT WILL BUILD WESTWARD FROM THE
WESTERN ATLANTIC INTO THE MID-ATLANTIC REGION BY EARLY NEXT WEEK.
SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH THE WEEKEND...BUT
SHOULD DIMINISH SOME NEXT WEEK AND BECOME MORE ISOLATED AND
TYPICAL OF SUMMER EARLY NEXT WEEK AS THE UPPER RIDGE BUILDS OVER
THE AREA.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1110 AM EDT FRIDAY...
FLASH FLOOD WATCH CONTINUES UNTIL 8 AM SATURDAY MORNING.
KFCX HAS BEEN REPAIRED AND IS BACK IN SERVICE.
SCATTERED SHOWERS AND THUNDERSTORMS...SOME WITH HEAVY RAINS
EXPECTED TO DEVELOP THIS AFTERNOON INTO TONIGHT. WITH PWAT STILL
RELATIVELY HIGH...LOW FFG AND VERY WET GROUND...THE POTENTIAL FOR
FLASH FLOODING CONTINUES. HRRR...AND RAP SEEM TO FOCUS ALONG
BLUE RIDGE AND EASTWARD THIS AFTERNOON INTO TONIGHT. UPPER LOW
PROGGED TO MOVE WESTWARD TODAY INTO WEEKEND. MADE SOME MINOR
ADJUSTMENTS IN POPS AND TEMPERATURES FOR THIS AFTERNOON.
MORE LATER....
AS OF 920 AM EDT FRIDAY...
FLASH FLOOD WATCH CONTINUES UNTIL 8 AM SATURDAY MORNING.
KFCX WILL BE DOWN THROUGH EARLY AFTERNOON FOR EMERGENCY REPAIRS.
PNS OUT WITH RAINFALL TOTALS.
THE 08AM/12Z RNK SOUNDING SHOWED PWATS ARE LOWER AT 1.09 INCHES
WITH NORTHERLY FLOW. INSTABILITY SHOULD BE LESS THIS AFTERNOON AS
MORE EASTERLY FLOW EVOLVES AROUND THE BUILDING ATLANTIC HIGH. BUT
WITH THE UPPER LOW...CONVECTION WITH POCKETS OF HEAVY RAIN WILL
DEVELOP THIS AFTERNOON INTO TONIGHT. THE THREAT FOR FLASH FLOODING
CONTINUES TODAY BECAUSE OF THE EXTREMELY LOW FFG VALUES...IN SOME
CASES LESS THAN 1.0 INCH/HR FOR FLASH FLOODING. ADJUSTED
TEMPERATURES AND DEWPOINTS FOR LATE MORNING INTO THIS AFTERNOON.
MODIFIED POPS INTO EARLY THIS AFTERNOON. WILL MAKE MORE
ADJUSTMENTS AS MORNING PROGRESSES.
AS OF 500 AM EDT FRIDAY...
FLASH FLOOD WATCH HAS BEEN EXTENDED UNTIL 8 AM SATURDAY MORNING.
EXCESSIVE RAINFALL IN PARTS OF THE FORECAST AREA THIS MORNING AS
UPPER LOW JUST TO OUR NORTHWEST COMBINED WITH VERY TROPICAL AIR
MASS ACROSS THE PIEDMONT CONTINUES. TRAINING AND BACKBUILDING
THUNDERSTORMS BROUGHT RECORD RAINFALL AMOUNTS TO DANVILLE
OVERNIGHT...WITH OVER FOUR INCHES OF RAIN AT THE DANVILLE AIRPORT
SINCE ABOUT 10 PM THURSDAY EVENING. RAINFALL OF THREE TO SIX
INCHES WAS COMMON ACROSS MUCH OF
CHARLOTTE...HALIFAX...PITTSYLVANIA...AND CAMPBELL COUNTIES.
SEVERAL WATER RESCUES REPORTED FROM DANVILLE CITY AND
PITTSYLVANIA COUNTY. MAIN STEM RIVER FLOODING ALSO ONGOING NOW AS
A RESULT ON THE ROANOKE AT RANDOLPH AND EXPECTED ON THE DAN LATER
TODAY AT SOUTH BOSTON.
THE DRYING EXPECTED A COUPLE OF DAYS AGO WILL BE POSTPONED UNTIL
NEXT WEEK UNFORTUNATELY. THE UPPER LOW TO OUR NORTHWEST WILL STALL
ACROSS WV AND THEN RETROGRADE SLOWLY TO THE WEST INTO KY/TN THROUGH
EARLY NEXT WEEK AS A MAMMOTH UPPER RIDGE EQUALLY RETROGRADE FROM
THE WESTERN ATLANTIC INTO THE MID-ATLANTIC REGION. THIS SHOULD
EVENTUALLY SHUT OFF THE EXCESSIVE RAINFALL AND RETURN US TO MORE
SUMMERLIKE CONDITIONS...BUT UNTIL THEN EXPECT MORE SHOWERS AND
THUNDERSTORMS.
THE GOOD NEWS FOR TODAY IS THAT PWATS ARE DOWN SLIGHTLY...MOSTLY
IN THE 1.5 TO 1.7 INCH RANGE AS OPPOSED TO 2.0+ INCHES. IN
ADDITION...INSTABILITY WILL BE LESS AS EASTERLY FLOW EVOLVES
AROUND THE BUILDING ATLANTIC HIGH. THERE SHOULD BE LESS INTENSE
CONVECTION AND MORE GENERAL STRATIFORM RAIN WITH EMBEDDED HEAVIER
CELLS. NONETHELESS...BECAUSE OF THE EXTREMELY LOW FFG VALUES...IN
SOME CASES LESS THAN 1.0 INCH/HR FOR FLASH FLOODING...HAVE OPTED
TO EXTEND THE FLASH FLOOD WATCH UNTIL 8 AM SATURDAY MORNING. HAVE
REMOVED ALLEGHANY COUNTY WHERE LESS RAINFALL HAS OCCURRED...BUT
ADDED SMYTH COUNTY AS SHRA/TSRA SPREAD IN THAT DIRECTION LATER
TODAY AND TONIGHT. THE MOST FAVORED AREAS AT THIS POINT FOR
ADDITIONAL HEAVY RAINFALL APPEAR TO BE SOUTH OF I-81...MOVING MORE
TOWARD OUR NW NC COUNTIES INTO THE WEEKEND. AS NOTED
ABOVE...HOWEVER...THE MAIN CONCERN IS ARE THE VERY LOW FFG VALUES
AND THE SIMPLE FACT THAT WE CANNOT TAKE HARDLY ANY ADDITIONAL
RAINFALL EAST OF THE ALLEGHANYS AT THIS POINT. THE WV COUNTIES
SHOULD BE JUST FINE AS THEY HAVE NOT HAD A FRACTION OF THE
RAINFALL MANY OF THE VA AND NC COUNTIES HAVE SEEN THE PAST TWO
WEEKS.
TEMPERATURES WILL REMAIN BELOW NORMAL THROUGH THE NEAR
TERM...THANKS TO CLOUDS...PCPN...AND EASTERLY FLOW.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
AN UPPER LEVEL RIDGE WILL BARREL TO THE WEST OVER THE WEEKEND. THIS
RIDGE WILL BE OFF THE MID ATLANTIC COAST ON SATURDAY THEN OVER THE
OHIO VALLEY BY SUNDAY NIGHT. THIS RIDGE WILL PUSH AN UPPER LEVEL LOW
WESTWARD ACROSS THE TENNESSEE VALLEY TO THE SOUTHERN PLAINS DURING
THE PERIOD. SHORT WAVES AND RAIN AXIS BETWEEN THESE TWO SYSTEMS WILL
BRING A GOOD CHANCE FOR RAIN TO THE REGION ON SATURDAY. WITH AN
EASTERLY UPSLOPE FLOW...HIGHER RAINFALL TOTALS WILL BE ALONG THE
BLUE RIDGE.
THIS RIDGE WILL BRING VERY WARM AND HUMID CONDITIONS TO THE REGION.
85H TEMPERATURES WILL WARM TO +22C BY MONDAY. TEMPERATURES ACROSS
THE MOUNTAIN WILL RANGE FROM THE LOWER TO MID 80S THIS WEEKEND. EAST
OF THE BLUE RIDGE WILL SEE TEMPERATURES APPROACHING 90F.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 300 PM EDT THURSDAY...
MODEL GUIDANCE HAS COME TO BETTER AGREEMENT ON THE EVOLUTION OF THE
UPPER-LEVEL PATTERN NEXT WEEK WHICH WILL FEATURE A BUILDING UPPER
LEVEL RIDGE OVER THE MID ATLANTIC. THE UPPER LOW WHICH DEVELOPS AND
BREAKS AWAY FROM THE UPPER TROUGH OVER NEW ENGLAND THIS WEEKEND IS
FORECAST TO RETROGRADE AND PUSH WEST-SOUTHWEST REACHING THE
SOUTHERN PLAINS BY THE MIDDLE OF NEXT WEEK...DAY 7.
THIS SUGGESTS LIFT FOR SHOWERS AND STORMS NEXT WEEK WILL BE LIMITED
TO DAYTIME HEATING...THE UPPER LOW MOVING TOO FAR WEST TO BE AN
INFLUENCE. IF THE RIDGE OF HIGH PRESSURE IS AS ROBUST AS FORECAST
597DM...THIS MAY CAUSE ENOUGH WARMING ALOFT TO POTENTIALLY LIMIT
DEEP CONVECTION TO LESS THAN 20 PERCENT COVERAGE EXCEPT FOR MAYBE
THE MOUNTAINS.
MODEL TEMPS HAVE TRENDED WARMER...BUT STILL NOTHING EXTREME. 85H
TEMPS ARE FCST TO BUILD CLOSE TO +20 DEG C BY MID WEEK WHICH SUGGEST
HIGH TEMPS WELL INTO THE 80S...POSSIBLY 90 URBAN AREAS. LOWS SHOULD
ALSO CREEP UPWARD A LITTLE WITH TMINS IN THE 60S TO AROUND 70.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
AS OF 730AM EDT FRIDAY...
BIZARRE SUMMER PATTERN WITH CLOSED UPPER LOW OVER THE AREA SCHEDULED TO
RETROGRADE TO MIDWEST OVER THE NEXT FEW DAYS. EXPECT LOW CLOUDS/FOG TO
BREAK UP LATER THIS MORNING WITH START OF DAYTIME HEATING...THOUGH EXPECTING
CIGS TO REMAIN MVFR FOR KLWB AND KBLF AS UPPER LOW AND TERRAIN INFLUENCES
HELP ENHANCE LIFT AND GENERATE SHOWERS. EXPECT A MORE DIURNAL FLAVOR TO
CIGS AND WEATHER AT OTHER LOCATIONS WITH SOME SHOWERS AND THUNDERSTORMS
REDEVELOPING THIS AFTERNOON. BELIEVE THE TRENDS WILL BE SIMILAR TO PREVIOUS
DAYS IN A WEAKLY FORCED ENVIRONMENT. DO NOT SEE ANY PARTICULAR FEATURES TO FOCUS
OR TIME CONVECIVE DEVELOPMENT SO WILL KEEP KBCB...KROA..KLYH...AND KDAY DRY EARLY
AND USE VICINITY AFTER 18Z.
AS UPPER LOW BEGINS ITS WWD TREK...A SHORT WAVE WILL DRIFT OVER THE AREA TONIGHT
WITH FLOW BECOMING SELY. HIS SHOULD KEEP SHOWERS IN THE AREA FOR THE OVERNIGHT.
MODELS ALSO SHOW MOISTURE SUCKING BACK WWD AS THE LOW MOVES...AND THIS SHOULD LEAD
TO IFR/LIFR CONDITIONS DEVELOPING OVERNIGHT.
.AVIATION EXTENDED...
DEEP EASTERLY FLOW CONTINUES INTO SATURDAY WITH WIDESPREAD SHOWERS
EXPECTED. SUNDAY THROUGH TUESDAY EXPECT A DAILY AFTERNOON AND
EVENING THREAT OF SHOWERS AND THUNDERSTORMS WITH EARLY MORNING IFR
BR/FG...BUT OVERALL IMPROVED CONDITIONS WITH MUCH MORE VFR THAN
CURRENT.
&&
.HYDROLOGY...
THE FLASH FLOOD WATCH CONTINUES THROUGH 8 AM EDT SATURDAY. GIVEN
THE EXPECTED WET PATTERN...IT MAY BE NECESSARY TO EXTEND INTO
SUNDAY MORNING...BUT HAVE DECIDED TO TAKE THIS ON A DAY-BY-DAY
BASIS. WE WILL EVENTUALLY GET OUT OF THIS PATTERN...BUT IT COULD
BE MONDAY BEFORE THAT HAPPENS IN EARNEST. IN THE MEANTIME...FFG
VALUES ARE EXTREMELY LOW AND ALTHOUGH INTENSE/ROBUST CONVECTION
SHOULD BE LESS WIDESPREAD TODAY...RAIN WILL BE OCCURRING OVER
AREAS THAT ARE EXCESSIVELY SATURATED AND SIMPLY CANNOT TAKE ANY
MORE RAINFALL AT ALL.
FLOOD WARNINGS IN EFFECT FOR THE FOLLOWING RIVERS IN VIRGINIA...DAN
RIVER NEAR PACES AFFECTING HALIFAX COUNTY FOR THE DAN RIVER...INCLUDING
PACES...MINOR FLOODING IS FORECAST. MINOR FLOODING IS ALSO OCCURING
ALONG THE ROANOKE RIVER AT RANDOLPH...DAN RIVER AT DANVILLE AND
SOUTH BOSTON. REFER TO LATEST FLOOD WARNINGS...RIVER FLOOD
WARNINGS AND FLOOD STATEMENTS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR VAZ009-012>018-
022>024-032>035-043>047-058-059.
NC...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR NCZ001>006-
018>020.
WV...NONE.
&&
$$
SYNOPSIS...RAB/KK
NEAR TERM...KK/RAB
SHORT TERM...RCS
LONG TERM...PM
AVIATION...MBS/RAB
HYDROLOGY...KK/RAB
AREA FORECAST DISCUSSION
NWS TUCSON AZ
248 PM MST FRI JUL 12 2013
.SYNOPSIS...WITH A BIT LESS ATMOSPHERIC MOISTURE OVER THE AREA EACH
DAY THROUGH SUNDAY THE SHOWER AND THUNDERSTORM ACTIVITY WILL
DIMINISH SOMEWHAT THROUGH THE WEEKEND WITH HIGH TEMPERATURES SLOWLY
RISING. THEN A WEATHER SYSTEM FROM THE PLAINS STATES WILL MOVE WEST
AND BEGIN TO AFFECT OUR WEATHER EARLY NEXT WEEK WITH MORE MOISTURE
AND INSTABILITY. THIS WILL INCREASE THE THREAT OF SHOWERS AND
THUNDERSTORMS MONDAY ONWARD WITH HIGH TEMPERATURES COOLING OFF A BIT
ONCE AGAIN.
&&
.DISCUSSION...WELL TODAY WAS INTERESTING. A WONDERFUL MCS PUSHED
NORTH ACROSS PIMA AND PINAL COUNTIES PROVIDING WIDESPREAD BENEFICIAL
RAINFALL. REPORTS GENERALLY RANGED FROM AROUND A TENTH UP TO A HALF
INCH ACROSS TUCSON...WITH THE MAX REPORTS AROUND FLORANCE WITH
OVER 2.5 INCHES OBSERVED. THINKING THE ATMOSPHERE IS NOW PRETTY
WORKED OVER IN THE CENTRAL ZONES SO THE BEST SHOT AT ANY CONVECTION
THIS AFTERNOON WOULD BE OVER COCHISE AND UP THROUGH GRAHAM AND
GREENLEE COUNTIES. ISOLATED ACTIVITY CAN NOT BE RULED OUT IN PIMA
AND COCHISE COUNTIES GIVEN THE RAPID WARMING WE HAVE EXPERIENCED IN
THE LAST FEW HOURS. THE HRRR ONLY HINTS AT A FEW STORMS THOUGH SO I
LOWERED PRECIP CHANCES A LITTLE THROUGH MIDNIGHT.
MODELS CONTINUE TO SHOW A DRYING TREND THROUGH SUNDAY. MID LEVEL DRY
AIR ADVECTION BRINGS OUR PRECIPITABLE WATER VALUES DOWN A FEW TENTHS
TOMORROW BUT THAT STILL LEAVES PLENTY OF MOISTURE FOR STORMS GIVEN
ENOUGH DAYTIME HEATING. WE ARE EXPECTING BETTER HEATING TOMORROW
ESPECIALLY IF WE CAN KEEP THE SKY CLEAR DURING THE MORNING HOURS.
MODELS SHOW LESS ACTIVITY OVER THE SIERRA MADRES TONIGHT SO THAT
WOULD SUGGEST FEWER CLOUDS IN THE MORNING. PLUS...THEIR IS A WEAK
PVU ANOMALY THAT MOVES INTO SE AZ AROUND 00Z SUNDAY. WRF DATA BREAKS
OUT PRECIP AROUND 3 PM TOMORROW AND THAT SEEMS REASONABLE.
MID LEVEL FLOW REALLY PULLS IN DRIER AIR SUNDAY AND DROPS OUR
PRECIPITABLE WATER VALUES DOWN TO AROUND 1.3 INCHES. THIS IS A
RESULT OF THE MONSOON RIDGE SPLITTING INTO TWO LOBES WITH ONE HIGH
PARKING OVER AZ/NM REGION WITH THE SECOND HIGH OVER THE NORTHEAST
UNITED STATES. WE SHOULD SEE A WARMING TREND IN ADDITION TO THE
DRIER CONDITIONS.
AFTER THAT...OUR PATTERN HAS THE POTENTIAL TO BECOME WET BY TUESDAY.
HERE IS WHAT WE DO KNOW ABOUT THE MID WEEK SYSTEM. FIRST...THE
OPERATIONAL GFS/ECMWF/CANADIAN ALL SHOW AN EASTERLY MOVING TROUGH AT
AROUND 40 DEG. LATITUDE STARTING OVER OHIO VALLEY ON SATURDAY AND
REACHING NEW MEXICO BY TUE. ENSEMBLE DATA SUPPORT THIS IDEA AS WELL.
WE ALSO KNOW THE MODELS ARE PROJECTING INCREASED MOISTURE WITH THIS
SYSTEM. MY CONCERN IS THE MOISTURE SOURCE. IT APPEARS THE MODELS ARE
TRYING TO RECYCLE THE MOISTURE AS IT TRAVELS AROUND OUR RIDGE THIS
WEEKEND. THE MOIST AIR TRAVELS NORTH INTO CANADA...THEN MOVES
SOUTH OVER COLORADO AND NEW MEXICO AS THE HIGH SPLITS AND PROVIDES
MORE NORTHEAST FLOW ALOFT INTO THE SW UNITED STATES. I WOULD THINK
SOME OF THE MOISTURE WOULD DISSIPATE ALONG THIS TRACK BUT THE MODELS
ARE ADAMANT THAT MOISTURE WILL BE AVAILABLE. EVENTUALLY...THERE IS A
MID LEVEL MOISTURE TAP INTO THE GULF OF MEXICO BUT THAT WOULD BE
LATE WEDNESDAY INTO THURSDAY.
SO WITH THAT IN MIND...I INCREASED RAIN CHANCES BY 5 OR 10 PERCENT
ON TUESDAY AND WEDNESDAY AND I AM CONCERNED THAT HEAVY RAIN WILL BE
POSSIBLE SOMETIME NEXT WEEK. THE EXACT TIME AND LOCATIONS ARE STILL
UP IN THE AIR THOUGH. IF THE GFS IS RIGHT...THEN WE NEED TO WATCH
FOR HEAVY RAIN AND FLOODING ON TUESDAY AND WEDNESDAY BUT COULD START
AS EARLY AS MONDAY NIGHT. EITHER WAY...NEXT WEEK LOOKS VERY
INTERESTING.
JJB
&&
.AVIATION...THUNDERSTORM ACTIVITY WILL BE LIMITED THROUGH THE
EVENING HOURS BUT SHOWERS OR THUNDERSTORMS MAY REDEVELOP AFTER 04Z.
OUTSIDE OF THE STORMS...VFR CIGS ARE ANTICIPATED WITH BKN100-120
DEVELOPING AFTER 04Z. WINDS WILL FOLLOW NORMAL DIURNAL TRENDS.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...SCATTERED MAINLY AFTERNOON THROUGH EARLY MORNING
SHOWERS AND THUNDERSTORMS WILL CONTINUE WITH A 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 40S WITH GOOD NIGHTTIME RECOVERIES. A
SLIGHT DRYING TREND IS EXPECTED LATE THIS WEEKEND.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION...UPDATED
NWS PHOENIX AZ
227 PM MST FRI JUL 12 2013
.UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS...
&&
.SYNOPSIS...
MOIST MONSOON AIR UNDER FAVORABLE SOUTHERLY FLOW WILL CONTINUE INTO
THIS EVENING...WITH SCATTERED TO NUMEROUS THUNDERSTORMS EXPECTED
OVER SOUTH CENTRAL ARIZONA...WITH ISOLATED THUNDERSTORMS ELSEWHERE.
DRIER AIR WILL BEGIN TO SLIDE INTO THE REGION ON SATURDAY...AND
ESPECIALLY ON SUNDAY AND MONDAY...WITH CHANCES OF SHOWERS AND
THUNDERSTORMS DECREASING EACH DAY. TEMPERATURES WILL BE WARMING TO
NEAR...OR ABOVE NORMAL VALUES NORMAL FOR THIS WEEKEND INTO EARLY
NEXT WEEK.
&&
.DISCUSSION...
AFTER A RATHER QUIET MORNING...A RATHER ACTIVE AFTERNOON
WEATHERWISE APPEARS TO BE ON TAP FOR SOUTH CENTRAL ARIZONA THIS
AFTERNOON AND EVENING. AS DEPICTED ON THE LAST SEVERAL RUNS OF THE
HOURLY HRRR MODEL...A LARGE COMPLEX OF THUNDERSTORMS THAT FORMED
LATE LAST NIGHT OVER NORTHERN SONORA MEXICO HAS HELD TOGETHER QUITE
WELL AND IS NOW PRODUCING A LINE OF STRONG THUNDERSTORMS THAT IS NOW
MOVING ACROSS PINAL COUNTY. THIS COMPLEX OF STORMS APPEARS TO BE
BEING SUPPORTED BY A SHORTWAVE/JET MAX THAT WAS PICKED UP ON THE 12Z
500MB ANALYSIS OVER SOUTHEAST ARIZONA. THESE STORMS HAVE ALREADY
PRODUCED DAMAGING WINDS...BLOWING DUST...SMALL HAIL...AND LOCAL
RAINFALL AMOUNTS IN EXCESS OF 1 INCH OVER PIMA AND PINAL COUNTIES.
LATEST HIGH-RESOLUTION MODEL RUNS TAKE THESE STORMS INTO THE GREATER
PHOENIX AREA THIS AFTERNOON...THEN RAPIDLY WEAKEN THEM THIS EVENING
AS THEY MAKE AN ATTEMPT TO PUSH INTO WESTERN ARIZONA AS THE
SUPPORTING SHORTWAVE RAPIDLY MOVES OFF TO THE NORTH AND WEAKENS.
SATURDAY APPEARS TO BE SETTING UP AS A QUIETER DAY...ESPECIALLY IF
TODAY`S THUNDERSTORM ACTIVITY WORKS OVER THE AIRMASS OVER THE
REGION. MODEL GUIDANCE IS IS GOOD AGREEMENT THAT RIDGING WILL BUILD
BACK WESTWARD INTO THE DESERT SOUTHWEST AS AN UPPER TROF MOVES INTO
THE PACIFIC NORTHWEST. LATEST NAM FORECAST SOUNDINGS DROP THE PWAT
VALUES OVER THE PHOENIX AREA TO AROUND 1.6 INCH ON SATURDAY
AFTERNOON...1.3 INCH ON SUNDAY AFTERNOON...AND 1.1 INCH ON MONDAY
AFTERNOON. CURRENT THINKING IS THAT THUNDERSTORM ACTIVITY WILL BE
CONFINED TO THE HIGHER TERRAIN NORTH AND EAST OF PHOENIX ON
SATURDAY...WITH LITTLE OR NO ACTIVITY ON SUNDAY AND MONDAY.
TEMPERATURES ARE EXPECTED TO WARM EACH DAY...WITH HIGHS APPROACHING
110F BY MONDAY.
ALTHOUGH WE ARE NOT COMPLETELY SOLD ON THE LONG RANGE MODEL
SOLUTIONS FOR THE MIDDLE OF NEXT WEEK...IT DOES LOOK LIKE A FAIRLY
SIGNIFICANT UPPER LOW MAY MAKE IT/S WAY ACROSS THE SOUTHERN PLAINS
INTO NEW MEXICO BY NEXT TUESDAY. IT IS TOO EARLY TO KNOW HOW MUCH
MOISTURE WILL BE AVAILABLE ACROSS THE REGION...BUT IF THIS SOLUTION
PANS OUT...THE MIDDLE OF NEXT WEEK COULD SEE VERY ACTIVE MONSOON
ACTIVITY ACROSS EASTERN ARIZONA AND POSSIBLY INTO THE LOWER DESERTS.
THE OVERALL FLOW DURING THIS TIME WILL LIKELY BE FROM THE NORTHEAST
ACROSS EASTERN ARIZONA AND FROM THE SOUTH ACROSS FAR WESTERN
ARIZONA. A SCENARIO LIKE THIS WOULD LIKELY RESULT IN DRY CONDITIONS
TO THE WEST OF PHOENIX AND AN ACTIVE MONSOON PERIOD ACROSS THE
HIGHER TERRAIN EAST OF PHOENIX. THE LONG RANGE TEMPERATURE OUTLOOK
SHOULD BRING NORMAL TO SLIGHTLY ABOVE NORMAL TEMPERATURES ACROSS OUR
WESTERN ZONES AND NEAR TO SLIGHTLY BELOW NORMAL FOR SOUTH-CENTRAL
AND EAST-CENTRAL ARIZONA.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX...KIWA AND KSDL...
BLOWING DUST HAS MOVED THROUGH ALL PHOENIX SITES...AND VSBYS SHOULD
GRADUALLY IMPROVE THROUGH 00Z. SOME LIGHT RAIN SHOWERS ALSO POSSIBLE
AT ALL PHOENIX SITES BUT SHOULD DISSIPATE QUICKLY. WINDS WILL REMAIN
SOUTHEASTERLY FOR THE DURATION OF THE AFTERNOON AND EVENING.
SOUTHEAST CA AND SOUTHWEST AZ...INCLUDING KIPL AND KBLH...MAINLY
LOOKING AT BLOWOFF HIGH CLOUDS ACROSS SE CA. CHANCES OF PRECIP AT
BOTH SITES IS SLIM...ONLY GOING TO MENTION SCT-BKN250. WINDS WILL
FAVOR TYPICAL DIURNAL PATTERNS THROUGH SATURDAY MORNING.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
STORM CHANCES WILL GRADUALLY RETURN TO THE AREA EARLY NEXT WEEK. 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...PERCHA/KUHLMAN
AVIATION...LEINS
FIRE WEATHER...LEINS
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
120 PM MST FRI JUL 12 2013
&&
.SYNOPSIS...
MOIST MONSOON AIR UNDER FAVORABLE SOUTHERLY FLOW WILL CONTINUE INTO
THIS EVENING...WITH SCATTERED TO NUMEROUS THUNDERSTORMS EXPECTED
OVER SOUTH CENTRAL ARIZONA...WITH ISOLATED THUNDERSTORMS ELSEWHERE.
DRIER AIR WILL BEGIN TO SLIDE INTO THE REGION ON SATURDAY...AND
ESPECIALLY ON SUNDAY AND MONDAY...WITH CHANCES OF SHOWERS AND
THUNDERSTORMS DECREASING EACH DAY. TEMPERATURES WILL BE WARMING TO
NEAR...OR ABOVE NORMAL VALUES NORMAL FOR THIS WEEKEND INTO EARLY
NEXT WEEK.
&&
.DISCUSSION...
AFTER A RATHER QUIET MORNING...A RATHER ACTIVE AFTERNOON
WEATHERWISE APPEARS TO BE ON TAP FOR SOUTH CENTRAL ARIZONA THIS
AFTERNOON AND EVENING. AS DEPICTED ON THE LAST SEVERAL RUNS OF THE
HOURLY HRRR MODEL...A LARGE COMPLEX OF THUNDERSTORMS THAT FORMED
LATE LAST NIGHT OVER NORTHERN SONORA MEXICO HAS HELD TOGETHER QUITE
WELL AND IS NOW PRODUCING A LINE OF STRONG THUNDERSTORMS THAT IS NOW
MOVING ACROSS PINAL COUNTY. THIS COMPLEX OF STORMS APPEARS TO BE
BEING SUPPORTED BY A SHORTWAVE/JET MAX THAT WAS PICKED UP ON THE 12Z
500MB ANALYSIS OVER SOUTHEAST ARIZONA. THESE STORMS HAVE ALREADY
PRODUCED DAMAGING WINDS...BLOWING DUST...SMALL HAIL...AND LOCAL
RAINFALL AMOUNTS IN EXCESS OF 1 INCH OVER PIMA AND PINAL COUNTIES.
LATEST HIGH-RESOLUTION MODEL RUNS TAKE THESE STORMS INTO THE GREATER
PHOENIX AREA THIS AFTERNOON...THEN RAPIDLY WEAKEN THEM THIS EVENING
AS THEY MAKE AN ATTEMPT TO PUSH INTO WESTERN ARIZONA AS THE
SUPPORTING SHORTWAVE RAPIDLY MOVES OFF TO THE NORTH AND WEAKENS.
SATURDAY APPEARS TO BE SETTING UP AS A QUIETER DAY...ESPECIALLY IF
TODAY`S THUNDERSTORM ACTIVITY WORKS OVER THE AIRMASS OVER THE
REGION. MODEL GUIDANCE IS IS GOOD AGREEMENT THAT RIDGING WILL BUILD
BACK WESTWARD INTO THE DESERT SOUTHWEST AS AN UPPER TROF MOVES INTO
THE PACIFIC NORTHWEST. LATEST NAM FORECAST SOUNDINGS DROP THE PWAT
VALUES OVER THE PHOENIX AREA TO AROUND 1.6 INCH ON SATURDAY
AFTERNOON...1.3 INCH ON SUNDAY AFTERNOON...AND 1.1 INCH ON MONDAY
AFTERNOON. CURRENT THINKING IS THAT THUNDERSTORM ACTIVITY WILL BE
CONFINED TO THE HIGHER TERRAIN NORTH AND EAST OF PHOENIX ON
SATURDAY...WITH LITTLE OR NO ACTIVITY ON SUNDAY AND MONDAY.
TEMPERATURES ARE EXPECTED TO WARM EACH DAY...WITH HIGHS APPROACHING
110F BY MONDAY.
ALTHOUGH WE ARE NOT COMPLETELY SOLD ON THE LONG RANGE MODEL
SOLUTIONS FOR THE MIDDLE OF NEXT WEEK...IT DOES LOOK LIKE A FAIRLY
SIGNIFICANT UPPER LOW MAY MAKE IT/S WAY ACROSS THE SOUTHERN PLAINS
INTO NEW MEXICO BY NEXT TUESDAY. IT IS TOO EARLY TO KNOW HOW MUCH
MOISTURE WILL BE AVAILABLE ACROSS THE REGION...BUT IF THIS SOLUTION
PANS OUT...THE MIDDLE OF NEXT WEEK COULD SEE VERY ACTIVE MONSOON
ACTIVITY ACROSS EASTERN ARIZONA AND POSSIBLY INTO THE LOWER DESERTS.
THE OVERALL FLOW DURING THIS TIME WILL LIKELY BE FROM THE NORTHEAST
ACROSS EASTERN ARIZONA AND FROM THE SOUTH ACROSS FAR WESTERN
ARIZONA. A SCENARIO LIKE THIS WOULD LIKELY RESULT IN DRY CONDITIONS
TO THE WEST OF PHOENIX AND AN ACTIVE MONSOON PERIOD ACROSS THE
HIGHER TERRAIN EAST OF PHOENIX. THE LONG RANGE TEMPERATURE OUTLOOK
SHOULD BRING NORMAL TO SLIGHTLY ABOVE NORMAL TEMPERATURES ACROSS OUR
WESTERN ZONES AND NEAR TO SLIGHTLY BELOW NORMAL FOR SOUTH-CENTRAL
AND EAST-CENTRAL ARIZONA.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX...KIWA AND KSDL...
CONVECTION TRYING TO WORK ITS WAY INTO THE METRO AREA FROM THE
SOUTH...BUT AS HAS BEEN THE CASE FOR THE PAST FEW DAYS...STORMS SEEM
TO BE DECAYING AS THEY DESCEND INTO THE DESERTS AND ENCOUNTER THE
MID LEVEL CAPPING INVERSION. THAT BEING SAID...HRRR MODEL AND TO
SOME EXTENT THE U-OF-A WRF MODELS TRY AND BRING THIS CONVECTION
INTO THE EAST VALLEY LATER THIS AFTERNOON. INTRODUCED VCSH AT ALL
PHOENIX TAF SITES BETWEEN 19-21Z ALTHOUGH MY CONFIDENCE IN
PREVAILING -SHRA REMAINS LOW. IF NOTHING ELSE...WIDESPREAD CIGS
BETWEEN 6-8KFT ARE LIKELY ACROSS THE AREA THIS AFTERNOON/EVENING.
WINDS WILL REMAIN WESTERLY UNTIL EARLY EVENING...BANKING ON OUTFLOWS
TO TURN THEM AROUND OUT OF THE EAST BY MID EVENING.
SOUTHEAST CA AND SOUTHWEST AZ...INCLUDING KIPL AND KBLH...
MAINLY LOOKING AT BLOWOFF HIGH CLOUDS ACROSS SE CA. CHANCES OF
PRECIP AT BOTH SITES IS SLIM...ONLY GOING TO MENTION SCT-BKN250.
WINDS WILL FAVOR TYPICAL DIURNAL PATTERNS THROUGH SATURDAY MORNING.
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...DUST STORM WARNING PHOENIX METRO AREA UNTIL 3PM TODAY. SEVERE
THUNDERSTORM WARNING NORTHERN PINAL AND SOUTHEAST MARICOPA COUNTY
UNTIL 1PM TODAY.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...PERCHA/KUHLMAN
AVIATION...LEINS
FIRE WEATHER...CDEWEY
AREA FORECAST DISCUSSION...UPDATED
NWS PHOENIX AZ
1036 AM MST FRI JUL 12 2013
.UPDATE...UPDATED AVIATION DISCUSSION...
&&
.SYNOPSIS...
MOIST MONSOON AIR UNDER FAVORABLE SOUTHERLY FLOW WILL CONTINUE INTO
THE WEEKEND...BUT SOME DRIER AIR WILL BEGIN TO SLIDE EASTWARD INTO
SOUTHWEST ARIZONA BY SUNDAY. CHANCES OF SHOWERS AND THUNDERSTORMS
CONTINUE...BUT WILL GRADUALLY DECREASE ACROSS THE LOWER DESERTS THIS
WEEKEND. THE COOLER TEMPERATURES WILL LAST FOR ANOTHER DAY OR TWO
BEFORE WARMING TO NEAR NORMAL FOR THIS WEEKEND INTO EARLY NEXT WEEK.
&&
.DISCUSSION...
A RATHER QUIET MORNING SO FAR ACROSS THE REGION. LATEST RADAR
IMAGERY IS ONLY SHOWING A FEW SHOWERS AND THUNDERSTORMS MOVING INTO
SOUTHWEST MARICOPA COUNTY...IN THE VICINITY OF GILA BEND...AND A FEW
SHOWERS OVER JOSHUA TREE NATIONAL PARK. A NEW CLUSTER OF
THUNDERSTORMS IS NOW SEEN ON SATELLITE IMAGERY TRYING TO MOVE
NORTHWARD ACROSS THE INTERNATIONAL BORDER INTO EXTREME SOUTHERN
PIMA COUNTY. THE LATEST (13Z) HRRR MODEL RUN WEAKENS THIS NEW
THUNDERSTORM COMPLEX AS IT CONTINUES TO MOVE IT NORTHWARD INTO
SOUTHERN PINAL COUNTY LATE THIS AFTERNOON...THEN BASICALLY
DISSIPATES IT THIS EVENING BEFORE IT REACHES OUR CWA. THIS MODEL
ALSO DEVELOPS SOME SHOWER ACTIVITY OVER GILA COUNTY BETWEEN NOW AND
20Z...THEN SLOWLY WEAKENS THIS ACTIVITY THEREAFTER INTO THE LATE
AFTERNOON AND EVENING HOURS. OTHER THAN SOME MINOR CHANGES IN THE
TEMPERATURE...DEWPOINT...AND POP GRIDS TO REFLECT CURRENT
TRENDS...THE LATEST GRIDDED FORECASTS STILL LOOK GOOD.
&&
.PREVIOUS DISCUSSION...
FOR HAVING SUCH A MOIST AIRMASS IN PLACE ACROSS THE REGION...THE
AMOUNT OF MONSOON ACTIVITY YESTERDAY WAS SOMEWHAT LACKING. THE
EXTENSIVE CLOUDINESS...THE LACK OF ANY FOCUS MECHANISM...AND GENERAL
CONFLUENT FLOW ALOFT ALL LED TO A FAIRLY QUIET MONSOON DAY ACROSS
THE CWA. CURRENT RADAR TRENDS DO SHOW A SMALL CLUSTER OF SHOWERS AND
THUNDERSTORMS MOVING NORTHWESTWARD INTO FAR SOUTHEAST ARIZONA.
HI-RES MODEL REFLECTIVITY INDICATES THIS CLUSTER SHOULD MAKE IT INTO
GILA COUNTY AT AROUND SUNRISE...BUT AT THE SAME TIME BE WEAKENING
CONSIDERABLY. THE REST OF THE AREA...SHOULD STAY DRY THROUGH THE
REST OF THE MORNING HOURS.
TODAY AND SATURDAY ARE EXPECTED TO BE LOW-GRADE MONSOON DAYS EVEN
THOUGH THERE IS AMPLE MONSOON MOISTURE ACROSS THE ENTIRE REGION.
SIMILAR TO YESTERDAY...DAYTIME HEATING WILL BE SOMEWHAT LIMITED DUE
TO THE VERY MOIST SOUNDING PROFILES AND THE EXPECTED CLOUD COVER. WE
SHOULD SEE A BIT MORE THUNDERSTORM ACTIVITY THIS AFTERNOON INTO
TONIGHT...INITIALLY FOCUSED ACROSS THE HIGHER TERRAIN ACROSS EASTERN
ARIZONA AND THEN POSSIBLY TRANSITIONING INTO THE LOWER DESERTS.
CAN/T COMPLETELY RULE OUT SOME STRAY SHOWERS AND THUNDERSTORMS
ANYWHERE ACROSS THE CWA TODAY DUE TO THE WIDESPREAD MOIST
CONDITIONS...BUT THE LACK OF ANY DIVERGENCE ALOFT SHOULD KEEP
DEVELOPMENT ISOLATED. THE MAIN THREAT TODAY WILL BE VERY HEAVY
DOWNPOURS AND A SLIGHT POSSIBILITY OF LOCALIZED FLASH FLOODING. THE
OVERALL WIND THREAT REMAINS LOW DUE TO THE MOIST ATMOSPHERIC
PROFILES.
BY SATURDAY...MODELS INDICATE DRYING WILL START TO WORK INTO
SOUTHEAST CALIFORNIA AND FAR SOUTHWEST ARIZONA VIRTUALLY ELIMINATING
RAIN CHANCES THERE. MAINLY SLIGHT CHANCES FOR AFTERNOON AND EVENING
SHOWERS AND THUNDERSTORMS ARE EXPECTED ACROSS THE SOUTH-CENTRAL
DESERTS AND HIGHER CHANCES ACROSS THE HIGHER TERRAIN NORTH AND EAST
OF PHOENIX. AS THE DRIER AIR FILTERS INTO THE REGION...TEMPERATURES
WILL BE ON THE RISE...REACHING NEAR OR SLIGHTLY ABOVE SEASONAL
NORMALS SATURDAY INTO EARLY NEXT WEEK. BY SUNDAY...EVEN THE
SOUTH-CENTRAL LOWER DESERTS SHOULD MAINLY BE DRY AS THE DRY FLOW
SLIDES EASTWARD.
ALTHOUGH WE ARE NOT COMPLETELY SOLD ON THE LONG RANGE MODEL
SOLUTIONS FOR THE MIDDLE OF NEXT WEEK...IT DOES LOOK LIKE A FAIRLY
SIGNIFICANT UPPER LOW MAY MAKE IT/S WAY ACROSS THE SOUTHERN PLAINS
INTO NEW MEXICO BY NEXT TUESDAY. IT IS TOO EARLY TO KNOW HOW MUCH
MOISTURE WILL BE AVAILABLE ACROSS THE REGION...BUT IF THIS SOLUTION
PANS OUT...THE MIDDLE OF NEXT WEEK COULD SEE VERY ACTIVE MONSOON
ACTIVITY ACROSS EASTERN ARIZONA AND POSSIBLY INTO THE LOWER DESERTS.
THE OVERALL FLOW DURING THIS TIME WILL LIKELY BE FROM THE NORTHEAST
ACROSS EASTERN ARIZONA AND FROM THE SOUTH ACROSS FAR WESTERN
ARIZONA. A SCENARIO LIKE THIS WOULD LIKELY RESULT IN DRY CONDITIONS
TO THE WEST OF PHOENIX AND AN ACTIVE MONSOON PERIOD ACROSS THE
HIGHER TERRAIN EAST OF PHOENIX. THE LONG RANGE TEMPERATURE OUTLOOK
SHOULD BRING NORMAL TO SLIGHTLY ABOVE NORMAL TEMPERATURES ACROSS OUR
WESTERN ZONES AND NEAR TO SLIGHTLY BELOW NORMAL FOR SOUTH-CENTRAL
AND EAST-CENTRAL ARIZONA.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX...KIWA AND KSDL...
CONVECTION TRYING TO WORK ITS WAY INTO THE METRO AREA FROM THE
SOUTH...BUT AS HAS BEEN THE CASE FOR THE PAST FEW DAYS...STORMS SEEM
TO BE DECAYING AS THEY DESCEND INTO THE DESERTS AND ENCOUNTER THE
MID LEVEL CAPPING INVERSION. THAT BEING SAID...HRRR MODEL AND TO
SOME EXTENT THE U-OF-A WRF MODELS TRY AND BRING THIS CONVECTION
INTO THE EAST VALLEY LATER THIS AFTERNOON. INTRODUCED VCSH AT ALL
PHOENIX TAF SITES BETWEEN 19-21Z ALTHOUGH MY CONFIDENCE IN
PREVAILING -SHRA REMAINS LOW. IF NOTHING ELSE...WIDESPREAD CIGS
BETWEEN 6-8KFT ARE LIKELY ACROSS THE AREA THIS AFTERNOON/EVENING.
WINDS WILL REMAIN WESTERLY UNTIL EARLY EVENING...BANKING ON OUTFLOWS
TO TURN THEM AROUND OUT OF THE EAST BY MID EVENING.
SOUTHEAST CA AND SOUTHWEST AZ...INCLUDING KIPL AND KBLH...
MAINLY LOOKING AT BLOWOFF HIGH CLOUDS ACROSS SE CA. CHANCES OF
PRECIP AT BOTH SITES IS SLIM...ONLY GOING TO MENTION SCT-BKN250.
WINDS WILL FAVOR TYPICAL DIURNAL PATTERNS THROUGH SATURDAY MORNING.
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...PERCHA/KUHLMAN
AVIATION...LEINS
FIRE WEATHER...CDEWEY
AREA FORECAST DISCUSSION
NWS TUCSON AZ
930 AM MST FRI JUL 12 2013
.SYNOPSIS...WITH A BIT LESS ATMOSPHERIC MOISTURE OVER THE AREA EACH
DAY THROUGH SUNDAY THE SHOWER AND THUNDERSTORM ACTIVITY WILL
DIMINISH SOMEWHAT THROUGH THE WEEKEND WITH HIGH TEMPERATURES SLOWLY
RISING. THEN A WEATHER SYSTEM FROM THE PLAINS STATES WILL MOVE WEST
AND BEGIN TO AFFECT OUR WEATHER EARLY NEXT WEEK WITH MORE MOISTURE
AND INSTABILITY. THIS WILL INCREASE THE THREAT OF SHOWERS AND
THUNDERSTORMS MONDAY ONWARD WITH HIGH TEMPERATURES COOLING OFF A BIT
ONCE AGAIN.
&&
.DISCUSSION...OVERNIGHT MCS THAT MOVED ACROSS COCHISE COUNTY INTO
GRAHAM AND GREENLEE COUNTIES HAS ALL BUT DISSIPATED. THIS SYSTEM DID
PRODUCE SOME SOLID RAINFALL SO WE WILL NEED TO WATCH FOR FLOOD
THREATS ACROSS THE SATURATED AREAS TODAY. ADDITIONAL MCS ACTIVITY
OVER THE SIERRA MADRES LAST NIGHT TRIGGERED A SERIES OF OUTFLOWS
THAT IN TURN PRODUCED NEW STORM COMPLEXES DOWNWIND. THE HI RES
MODELS ARE HAVING TROUBLE WITH THE COMPLEX CURRENTLY MOVING INTO
SANTA CRUZ AND PIMA COUNTIES. THE HRRR DID SHOW SOME WEAK STORMS
REACHING FAR SOUTHERN AZ...AND IS CURRENTLY ON TOP OF THE CLOUD
COVER. PLUS...MOISTURE CONTENT IS STILL HIGH SO ANY REMNANT OUTFLOWS
FROM THE MCS OVER SOUTHERN AZ MAY KEEP CONVECTION GOING FOR A FEW
MORE HOURS
WITH THAT IN MIND...I TEND TO FAVOR THE HRRR TODAY WHICH SHOWS A
SIMILAR EVOLUTION AS YESTERDAY. THAT DOES MAKE SENSE GIVEN OUR 12Z
SOUNDING WHICH SHOWS A SIMILAR PROFILE AS YESTERDAY. A THICK VEIL OF
CLOUDS SITS OVER MUCH OF SE AZ AND IT WILL TAKE SOME TIME FOR THE
CLOUDS TO DISSIPATE MEANING OUR SURFACE HEATING POTENTIAL WILL BE
LIMITED. CURRENTLY...WE ARE RUNNING ABOUT A DEGREE WARMER THAN
YESTERDAY...AND THE CONVECTIVE TEMP FOR TODAY SHOULD BE SLIGHTLY
LOWER THAN YESTERDAY. SO I DONT THINK THE MORNING CLOUD COVER WILL
COMPLETELY ELIMINATE STORM CHANCES TODAY...BUT IT MAY KEEP THE
INTENSITY AND COVERAGE DOWN TO MORE ISOLATED TO SCATTERED STORMS.
GIVEN OUR RECENT RAIN IN THE SOUTHERN ZONES AND HI MOISTURE CONTENT
IN THE ATMOSPHERE...I AM AGAIN CONCERNED ABOUT FLOODING. AN ISOLATED
DOWNBURST ALSO IS POSSIBLE AS WE ARE CURRENTLY EXPERIENCING GUSTY
WINDS OUT OF THE SOUTHERN AZ MCS.
JJB
&&
.AVIATION...CONTINUED ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS MOVING NNW AT 10-15 KTS THROUGH THIS EVENING OR
08/06Z. ISOLATED CIGS 0F 3-4K FT NEAR THE STRONGER TSTMS WITH VSBYS
POTENTIALLY AS LOW AS 1/2 TO 1SM DUE TO HEAVY RAIN. OUTSIDE OF THE
THUNDERSTORMS...SURFACE WINDS DIURNALLY DRIVEN LESS THAN 10 KTS.
CLOUDS SCT060-080 BKN100-120. AVIATION DISCUSSION NOT UPDATED FOR
TAF AMENDMENTS.
&&
.FIRE WEATHER...SCATTERED MAINLY AFTERNOON THROUGH EARLY MORNING
SHOWERS AND THUNDERSTORMS WILL CONTINUE WITH A 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 40S WITH GOOD NIGHTTIME RECOVERIES. A
SLIGHT DRYING TREND IS EXPECTED LATE THIS WEEKEND.
&&
.PREV DISCUSSION...SOME SHOWERS AND THUNDERSTORMS ARE NOW MOVING
ACROSS EXTREME SE AZ EARLY THIS MORNING AND THESE SHOULD CONTINUE
NNW AND SLOWLY DIE OFF OVER THE NEXT SEVERAL HOURS. THEN AS WE MOVE
INTO THE DAY...WITH ABUNDANT LOW LEVEL MOISTURE AND SUFFICIENT
INSTABILITY IN PLACE ACROSS THE REGION...CONVECTION IS EXPECTED TO
FIRE UP LATE THIS MORNING RESULTING IN SCATTERED SHOWERS AND
THUNDERSTORMS FOR THE AFTERNOON AND EVENING HOURS. TIMING OF THE
DEVELOPMENT WILL BE SIMILAR TO YESTERDAY WITH SIMILAR STEERING FLOW
PUSHING THE STORMS TO THE NNW. WITH A BIT LESS MID AND UPPER LEVEL
MOISTURE TO WORK WITH THE STORMS SHOULD BE SLIGHTLY LESS EFFICIENT
RAINFALL PRODUCERS AND WITH A LACK OF A STRONG LIFTING MECHANISM THE
INTENSITIES SHOULD BE HELD IN CHECK FOR THE MOST PART.
THIS THEME CONTINUES INTO THE WEEKEND WITH LOWER LEVELS OF
ATMOSPHERIC MOISTURE FOR THE CONVECTION TO WORK WITH SO WILL HAVE AN
OVERALL TREND OF LESS SHOWER AND STORM COVERAGE EACH DAY AND LESS
INTENSE RAINFALL WITH THE STORMS. HOWEVER...LESS MOISTURE WILL
BRING ABOUT A SOMEWHAT ENHANCED THREAT OF STRONG OUTFLOW WINDS WITH
THE STRONGER STORMS DUE TO A DRIER BOUNDARY LAYER. LESS MOISTURE
ALSO MEANS MORE SUNSHINE RESULTING IN HIGHER AFTERNOON
TEMPERATURES. THE HIGH TEMPERATURES WILL BE A COUPLE OF DEGREES
WARMER EACH DAY THROUGH SUNDAY WITH SUNDAY LIKELY THE WARMEST DAY
BEFORE TEMPS BEGIN TO COOL A BIT AGAIN.
THE AFOREMENTIONED COOL DOWN IS THE RESULT OF AN INTERESTING
SITUATION THAT WILL RESULT IN AN ACTIVE PATTERN NEXT WEEK IF IT
COMES TO PASS AS CURRENTLY MODELED. AN UPPER LEVEL LOW CURRENTLY
CENTERED OVER OHIO IS PROGGED TO MOVE WSW ACROSS THE COUNTY THIS
WEEKEND EVENTUALLY ENDING UP IN THE VICINITY OF NEW MEXICO TOWARD
THE END OF NEXT WEEK. WHILE DEFINITELY NOT THE NORM NEARLY ALL
MODEL SOLUTIONS HAVE PICKED UP ON THIS AND THE LAST FEW HOURS OF THE
WATER VAPOR LOOP SHOWS THE LOW BEGINNING TO TURN TOWARD THE
SOUTHWEST AT THIS TIME. WHAT THIS WOULD RESULT IN IS AN INCREASE IN
DEEP MOISTURE FROM EAST TO WEST BEGINNING MONDAY AND REMAINING OVER
THE AREA THROUGH THE WEEK WITH ENHANCED INSTABILITY JUST FOR ADDED
FUN. WITH THIS SETUP WE WOULD END UP WITH PLENTY OF CONVECTION EACH
DAY THAT WOULD LIKELY LAST WELL INTO THE NIGHT AND THE STORMS WOULD
BE EFFICIENT RAINFALL PRODUCERS DUE TO THE HIGH LEVEL OF
PRECIPITABLE WATER VALUES FORECAST. THE INCREASE IN CONVECTIVE
ACTIVITY AND THE ASSOCIATED CLOUD COVER WILL SUPPRESS AFTERNOON
TEMPERATURES TO A FEW DEGREES BELOW NORMAL TUESDAY ONWARD. WILL BE
INTERESTING TO SEE HOW THIS PLAYS OUT. CERNIGLIA
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS PUEBLO CO
326 PM MDT FRI JUL 12 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 246 PM MDT FRI JUL 12 2013
THUNDERSTORMS DEVELOPED EARLIER TODAY THAN PAST FEW DAYS AND ARE
DEFINITELY MORE NUMEROUS ACROSS WESTERN AREAS BENEATH THE MONSOON
PLUME...AIDED BY SHORTWAVE ENERGY LIFTING NORTHWARD OUT OF NEW
MEXICO. 4KM WRF SEEMS TO HAVE HANDLED THE CONVECTION BETTER THAN
MORNING HRRR RUNS SO FAR. BURN SCARS HAVE BEEN LARGELY MISSED AS OF
20Z...HOWEVER THAT COULD CHANGE BEFORE THE EVENING IS OUT WITH LOTS
OF ACTIVITY IN NORTHERN NM WORKING ITS WAY SLOWLY NORTHWARD. WITH
PRECIP WATERS RUNNING ANYWHERE FROM 112-185 PERCENT OF NORMAL
(HIGHEST VALUES OUT WEST)...THUNDERSTORMS THROUGH THIS EVENING WILL
BE EFFICIENT HEAVY RAINERS...WHICH WILL ELEVATE CONCERNS FOR FLASH
FLOODING ON BURN SCARS. THE WEST FORK COMPLEX IS MOST UNDER THE GUN
FOR THIS...SO WILL CONTINUE WITH THE FLASH FLOOD WATCH. WITH FLOW
ALOFT FROM THE SOUTH SOUTHWEST...MOST THUNDERSTORMS WILL BE TIED TO
THE HIGHER TERRAIN...BUT HRRR SUGGESTS AN ISOLATED SHOWER OR TWO NOT
OUT OF THE QUESTION...ESPECIALLY ALONG THE I-25 CORRIDOR AS OUTFLOWS
COME OFF THE MOUNTAINS. DUE TO THE SLOW MOVEMENT OF THUNDERSTORMS
TODAY...FLASH FLOODING WILL ALSO BE POSSIBLE ON THE BURN SCARS IN
THE EASTERN MOUNTAINS IF A STRONGER STORM WERE TO DEVELOP OVER
THEM.
THUNDERSTORMS WILL GRADUALLY DIMINISH THIS EVENING AS WE LOOSE
HEATING. WE GET TO DO IT ALL OVER AGAIN FOR SATURDAY. SOME SUBTLE
DIFFERENCES WILL BE MORE EASTERLY LOW LEVEL FLOW ACROSS NORTHERN
PORTIONS OF THE SOUTHEAST PLAINS BEHIND A WEAK FRONT WHICH DROPS IN
TONIGHT. DEW POINTS DON`T APPEAR TO BE THAT MUCH DIFFERENT FROM
TODAY...THUS LCLS ARE SIMILAR AS WELL. AND WITH UPPER HIGH CENTER
SHIFTING SOUTH OF THE AREA...STORM MOTIONS MAY ATTAIN A BIT MORE OF
A WESTERLY COMPONENT THAN TODAY WHICH MAY HELP THEM MOVE FARTHER
EAST OFF THE MOUNTAINS AND INTO THE ADJACENT PLAINS OF EL PASO
COUNTY. NAM12 IS ALSO DEVELOPING CONVECTION ACROSS THE SOUTHEAST
PLAINS ALONG THE STALLED FRONTAL BOUNDARY WHICH SETS UP ALONG A LINE
FROM ROUGHLY TRINIDAD TO LA JUNTA TO EADS. CAPES NOT ALL THAT HIGH
AND SHEARS ARE DEFINITELY WEAK...SO NOT EXPECTING THEM TO BE TOO
STRONG. HOWEVER WITH NOT MUCH CHANGE IN PRECIPITABLE WATERS...HEAVY
RAINERS WILL ONCE AGAIN BE THE MAIN THREAT WITH FLASH FLOODING
POSSIBLE ON THE AREA BURN SCARS. DIFFICULT TO PICK OUT ANY
SHORTWAVES EMBEDDED IN THE FLOW TO HELP ENHANCE COVERAGE...BUT WEST
FORK BURN SCAR MAY BE MOST UNDER THE GUN FOR FLASH FLOODING BASED ON
AVAILABLE MOISTURE. WILL LET LATER SHIFTS LOOK AT LATEST
HIGH RES MODELS BEFORE ISSUING ANY MORE FLASH FLOOD WATCHES.
WALDO...BLACK FOREST...AND OTHER BURN SCARS ACROSS THE SOUTHEAST
MOUNTAINS WILL ALSO BE UNDER THE GUN AGAIN...SO THOSE IN AND
NEAR THE BURN SCARS NEED TO MAINTAIN A HEIGHTENED AWARENESS FOR THE
POTENTIAL FOR FLASH FLOODING OVER THE WEEKEND AND ESPECIALLY INTO
SUNDAY (SEE DISCUSSION BELOW). -KT
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 246 PM MDT FRI JUL 12 2013
...HEAVY RAIN POSSIBLE SUNDAY AND INTO MONDAY...
.SUNDAY AND MONDAY...MAIN THREATS ARE POTENTIAL FOR HEAVY RAINS
AND SEE HYDRO DISCUSSION FOR MORE DETAILS.
.TUESDAY THROUGH FRIDAY...MAIN CHALLENGE IS THE AMOUNT OF
MOISTURE WHICH WILL INFLUENCE THE AMOUNT OF AFTERNOON AND EVENING
CONVECTION. THE EC AND GFS SUGGEST DRIER AIR ALOFT WILL ADVECT
INTO THE REGION FROM THE EAST AS THE UPPER LOW MOVES INTO ARIZONA
AND WEAKENS. MAIN DIFFERENCE IS THE AMOUNT OF MOISTURE WHICH
GRADUALLY MOVES NORTHWARD DURING THE LATTER PART OF THE WEEK. EC
IS STRONGER WITH THE RIDGE OVER THE WESTERN US KEEPING THE REGION
DRIER...WHILE THE GFS HAS MORE MOISTURE WITH A WEAKER RIDGE. THE
EXTENDED MODELS HAVE BEEN HAVING TROUBLE WITH THE FINER DETAILS
LATELY. FOLLOWED THE CR EXTENDED PROCEDURE CLOSELY WHICH HAS
GENERALLY SCATTERED CONVECTION OVER THE MOUNTAINS. BELIEVE THE
MOST LIKELY SOLUTION IS TO HAVE ENOUGH MOISTURE FOR CONVECTION
OVER THE MOUNTAINS...WITH MOSTLY LIGHT TO MODERATE RAINFALL
AMOUNTS. --PGW--
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 246 PM MDT FRI JUL 12 2013
VCTS WILL BE POSSIBLE THROUGH EARLY EVENING AT BOTH KCOS AND KALS.
KPUB COULD SEE SOME ERRATIC WINDS LATER THIS AFTERNOON...BUT IS
LEAST LIKELY TO SEE -TSRA ACTIVITY AS THUNDERSTORMS STAY TIED MAINLY
TO THE HIGHER TERRAIN. LOCALLY HEAVY RAIN WILL BE THE PRIMARY
THREATS. OTHERWISE...VFR CIGS/VIS EXPECTED OUTSIDE OF
THUNDERSTORMS. THUNDERSTORM ACTIVITY SHOULD DIMINISH THIS EVENING
WITH LOSS OF HEATING. WINDS WILL BECOME NORTHERLY AT KCOS AND KPUB
OVERNIGHT AS A WEAK FRONT DROPS IN FROM THE NORTH. WINDS WILL SHIFT
OUT OF THE EAST FOR SATURDAY FOR KCOS AND KPUB. ANOTHER ROUND
OF SCATTERED AFTERNOON THUNDERSTORMS WILL DEVELOP ACROSS THE
MOUNTAINS AND COULD MOVE INTO THE ADJACENT TAF SITES DURING THE
AFTERNOON WITH KCOS AND KALS MOST LIKELY TO SEE -TSRA ACTIVITY. MAIN
THREAT WITH THUNDERSTORMS WILL BE LOCALLY HEAVY RAIN AND ERRATIC
GUSTY WINDS. -KT
&&
.HYDROLOGY...
ISSUED AT 246 PM MDT FRI JUL 12 2013
...HEAVY RAIN POSSIBLE SUNDAY AND MONDAY...
MODELS CONTINUE TO SUGGEST THE THREAT FOR SOME HEAVY RAINFALL
SUNDAY OVER THE INTERSTATE 25 CORRIDOR AND EASTERN MOUNTAINS.
UNUSUAL WEATHER PATTERN DEVELOPING WITH UPPER LOW OVER OHIO MOVING
WESTWARD AND REACHING COLORADO BY MONDAY. BEING AN UNUSUAL WEATHER
PATTERN...HAVE NO EXPERIENCE WITH SIMILAR EVENTS. MODELS CONTINUE TO
MOISTEN THE WESTERN SIDE OF THE UPPER LOW. MODELS ARE ALSO SIMILAR
WITH A DISTURBANCE ON THE LEADING EDGE OF THE UPPER LOW REACHING
EASTERN COLORADO SUNDAY AND SUNDAY EVENING. THERE IS DEEP EASTERLY
FLOW UP TO AT LEAST 700MB SUNDAY WHICH SHOULD MOISTEN THE LOWER
LAYERS. WITH THE MOIST EASTERLY FLOW IN THE LOWER LAYERS...MOIST
AIR ALOFT AND WEAK DISTURBANCE...THE THREAT FOR HEAVY RAINS OVER
THE INTERSTATE 25 CORRIDOR AND EASTERN MOUNTAINS CONTINUE. THE
AMOUNT OF RAIN WILL DEPEND ON THE FINER DETAILS WHICH ARE STILL
EVOLVING. LATEST SIMULATIONS HAVE THE WINDS ALOFT BECOMING MORE
EASTERLY WHICH WOULD TEND TO PROPAGATE STORMS WESTWARD MORE
QUICKLY. IF THE UPPER LEVELS ARE NOT AS MOIST OR SLIGHTLY
WARMER...THEN THERE IS THE POTENTIAL FOR THE ATMOSPHERE TO REMAIN
CAPPED WITH POSSIBLY A LONGER DURATION LIGHT PRECIPITATION EVENT.
GIVEN THE SENSITIVITY OF THE BURN SCARS TO LOCAL DOWNPOURS...HAVE
DECIDED TO INCLUDE MENTION OF HEAVY RAIN IN THE ZONES AND HWO. AS
THE UPPER LOW MOVES TO THE SOUTH ON MONDAY...WARMER AND DRIER AIR
ALOFT WILL TEND TO LIMIT CONVECTION AND REDUCE THE THREAT FOR
HEAVY RAIN. AREA OF HEAVIER RAIN WILL MOVE WESTWARD..POSSIBLY
BEING CENTERED ON THE SOUTHWEST MOUNTAINS...INCLUDING THE WEST
FORK COMPLEX. --PGW--
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 9 PM MDT THIS EVENING FOR COZ067-068.
&&
$$
SHORT TERM...KT
LONG TERM...PGW
AVIATION...KT
HYDROLOGY...PGW
AREA FORECAST DISCUSSION
NWS MIAMI FL
239 PM EDT FRI JUL 12 2013
.SHORT TERM (TONIGHT-SATURDAY NIGHT)...
THE LATEST WATER LOOP SHOWED AN UPPER LOW CENTERED JUST SOUTH OF THE
LOCAL AREA OVER THE KEYS WITH PLENTY OF MOISTURE SPREADING NORTH TO
ITS EAST OVER THE ADJACENT ATLANTIC WATERS AND BAHAMAS. THE
AFTERNOON SURFACE ANALYSIS SHOWED A TROUGH OF LOW PRESSURE JUST OFF
THE SE FLORIDA COAST ASSOCIATED WITH WHAT IS LEFT OF CHANTAL AND A
WEAK FRONTAL BOUNDARY EXTENDING WSW FROM SC TO MS. THIS SFC TROUGH
NEAR THE AREA COMBINED WITH THE UPPER LOW AND PLENTY OF DEEP LAYER
MOISTURE WILL CONTINUE TO INFLUENCE THE LOCAL WEATHER THROUGH
SATURDAY WITH SCATTERED/NUMEROUS SHOWERS/TSTMS DEVELOPING EACH
DAY.
THE LOCALLY RUN 1.5 KM WRF AND 13Z HRRR MODEL REFLECTIVITIES ARE IN
DECENT AGREEMENT WITH THE LATEST TRENDS THIS AFTERNOON AND CONTINUE
TO INDICATE THE LATE AFTERNOON ACTIVITY BECOMING MORE WIDESPREAD AND
FOCUSED ACROSS THE EASTERN HALF OF THE SRN FL PENINSULA WITH THE
SW LOW/MID-LEVEL FLOW IN PLACE. ONE OF THE MAIN CONCERNS THROUGH
THE REMAINDER OF THE DAY WILL BE THE POTENTIAL FOR LOCALIZED HEAVY
RAINFALL ACROSS THE EAST COAST AND METRO AREAS...WHICH COULD
QUICKLY RESULT IN URBAN FLOODING OVER THE TYPICALLY FLOOD PRONE
AREAS. ALTHOUGH THIS ACTIVITY IS FORECAST TO TREND DOWN THROUGH
THE LATE EVENING HOURS...THE PREVIOUSLY DISCUSSED SYNOPTIC
FEATURES COMBINED WITH A MID-LEVEL VORT MAX LIFTING NORTH ALONG
THE EAST COAST WILL BE ENOUGH TO KEEP THE RAIN CHANCES UP ACROSS
THE ADJACENT MARINE AREAS THROUGH THE OVERNIGHT HOURS...WHICH MAY
INFLUENCE THE IMMEDIATE COASTAL LOCATIONS.
THE PREVIOUSLY DISCUSSED UPPER LOW AND SURFACE TROUGH OFF THE EAST
COAST WILL BEGIN TO LIFT NORTH AND NORTHWEST OF THE LOCAL AREA LATER
TONIGHT THROUGH SATURDAY NIGHT. HOWEVER...THE LATEST NUMERICAL
GUIDANCE DEPICTS DEEP SOUTHERLY FLOW CONTINUING TO ADVECT MOISTURE
NORTHWARD OUT OF THE CARIBBEAN ACROSS THE FLORIDA PENINSULA THROUGH
THIS TIME. MODEL PWAT SOLUTIONS SHOW A PLUME OF 2-2.1" VALUES
STREAMING OVERHEAD...WHICH WILL SUPPORT WELL ABOVE NORMAL RAIN
CHANCES CONTINUING THROUGH THE DAY SATURDAY. THE MAIN IMPACTS AND
CONCERNS WILL BE LOCALIZED FLOODING WHERE ANY ACTIVITY BECOMES
FOCUSED OVER A PERIOD OF TIME. 85/AG
.LONG TERM (SUNDAY-FRIDAY)...
THE WEATHER PATTERN SUNDAY AND BEYOND WILL FEATURE THE ATLANTIC
RIDGE BUILDING BACK IN. A TYPICAL SUMMERTIME PATTERN IS EXPECTED.
THERE IS ONE FEATURE OF NOTE - AN INVERTED TROUGH EAST OF OUR AREA
ALONG ABOUT 55 DEGREES WEST LONGITUDE. THIS FEATURE BROKE OFF FROM
THE MID LATITUDE WESTERLIES AND IS NOW TRAVELING WESTWARD. BOTH
GFS AND ECMWF TRACK THIS TROUGH ACROSS SOUTH FL ON MONDAY, RATHER
AMPLIFIED WITH NE WINDS AHEAD OF IT AND SE WINDS BEHIND IT.
THIS FEATURE COULD ENHANCE SHOWER AND THUNDERSTORM ACTIVITY AS
IT PASSES ON MONDAY.
57/GREGORIA
&&
.AVIATION...
SCATTERED CONVECTION WILL CONTINUE ACROSS THE SOUTH FLORIDA AREA
THROUGH THE AFTERNOON. LATEST HRRR KEEPS THE ACTIVITY CONFINED ALONG
THE INTERIOR AND EAST COASTAL AREAS THROUGH THE EARLY EVENING HOURS.
KEPT VCTS MENTION AT EACH EAST COAST SITE FROM KMIA NORTHWARD. BRIEF
IFR CONDITIONS CAN BE EXPECTED WITHIN ANY TSRA. FLOW WILL BECOME
MORE SOUTHERLY TOMORROW WITH BETTER COVERAGE OF AFTERNOON SHOWERS
AND THUNDERSTORMS EXPECTED.
&&
.MARINE...
A WEAK TROUGH OF LOW PRESSURE AND AN UPPER LOW WILL CONTINUE TO
GENERATE SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ACROSS THE
MARINE AREAS INTO TONIGHT...ESPECIALLY OVER THE ATLANTIC WATERS.
ALTHOUGH WINDS AND SEAS WILL GENERALLY REMAIN LOW THROUGH THE
WEEKEND...CONDITIONS CAN QUICKLY CHANGE IN AND AROUND HEAVY SHOWERS
AND STORMS. LIGHT TO MODERATE EASTERLY WINDS AND SEAS WILL RETURN
SUNDAY AS THIS TROUGH OF LOW PRESSURE LIFTS NORTH OF THE AREA.
ANOTHER TROUGH IS FORECAST TO APPROACH THE FLORIDA PENINSULA THROUGH
THE DAY MONDAY AND MAY LEAD TO HIGHER RAIN CHANCES ONCE AGAIN.
&&
.FIRE WEATHER...
NO CONCERNS AS RELATIVE HUMIDITIES ARE FORECAST TO REMAIN ABOVE
CRITICAL LEVELS EACH DAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 75 89 76 89 / 40 70 40 50
FORT LAUDERDALE 74 87 77 89 / 40 70 40 50
MIAMI 76 88 76 89 / 40 70 40 50
NAPLES 74 89 75 88 / 30 70 40 50
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...85/AG
AVIATION/RADAR...10/CD
AREA FORECAST DISCUSSION
NWS GOODLAND KS
226 PM MDT FRI JUL 12 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 1255 PM MDT FRI JUL 12 2013
LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOWS 593 DM RIDGE EXTENDING
ACROSS THE PLAINS INTO THE NORTHERN MISSISSIPPI VALLEY...WITH CLOSED
576 DM LOW OVER OHIO RIVER VALLEY DOWNSTREAM...AND TROUGH IN PLACE
ACROSS PACIFIC NORTHWEST. THIS RIDGE WILL KEEP VERY HOT TEMPS IN
PLACE THE NEXT FEW DAYS WITH MINIMAL PRECIP CHANCES.
IMMEDIATE CONCERN IS VERY HOT TEMPERATURES ACROSS THE AREA THIS
AFTERNOON. SOUTHERLY FLOW HAS KEPT TD VALUES AROUND 60F IN PLACE
ACROSS THE EASTERN PART OF OUR CWA...WHICH SHOULD SUPPORT HEAT
INDICES AROUND 105F DURING PEAK HEATING. THOUGH I COULD SEE THIS AS
A MARGINAL SITUATION...PER COORDINATION AND LOCAL GUIDANCE I WENT
AHEAD AND ISSUED AT HEAT ADVISORY THROUGH 00Z.
SHORT RANGE GUIDANCE CONTINUES TO SUPPORT THUNDERSTORM INITIATION
ALONG SURFACE TROUGH AXIS NEAR OUR CWA BORDER. WITHOUT LARGE SCALE
FORCING IN PLACE...THIS ACTIVITY WILL PROBABLY BE TIED TO PEAK
HEATING...WITH CHANCES QUICKLY DIMINISHING AFTER SUNSET. I WENT
AHEAD AND INCLUDED ISO THUNDER MENTION...THOUGH CONFIDENCE IS PRETTY
LOW. LCL VALUES ARE GENERALLY IN THE 12-14KFT RANGE AND WITH DEEP
DRY LAYER BELOW WE MAY NOT ACTUALLY SEE MUCH REGARDING MEASURABLE
PRECIP WITH ANY OF THESE STORMS THAT DO DEVELOP. WITH DCAPE IN
EXCESS OF 1500 J/KG IS ALSO FORECAST BY BOTH RAP AND NAM BY THIS
AFTERNOON...SO STRONG GUSTS ARE CERTAINLY POSSIBLE WITH THESE STORMS.
SURFACE TROUGH BEGINS TO SHIFT SOUTH AND EAST SATURDAY...WHICH COULD
ALLOW SLIGHTLY COOLER TEMPS (AT LEAST SUB 100F) TO MOVE INTO THE
NORTHWEST PART OF THE CWA. THIS COULD ALSO SHIFT SW FLOW FURTHER
SOUTH KEEPING TD VALUES LOWER WHERE HIGHEST TEMPS ARE...SO CHANCE
FOR HEAT INDICES AROUND 105 SEEMS MUCH LOWER. GUIDANCE IS STILL
SHOWING THUNDERSTORMS INITIATING IN THE EARLY AFTERNOON ALONG AND
BEHIND THIS TROUGH AXIS. IT LOOKS LIKE A VERY SIMILAR SITUATION AS
TODAY WITH LITTLE IN THE WAY OF FORCING BEYOND DESTABILIZATION ALONG
TROUGH AXIS IN THE AFTERNOON/EVENING. WE COULD SEE INITIATION FURTHER
EAST DEPENDING ON TROUGH LOCATION. AT THIS TIME I DECIDED AGAINST
EXPANDING POPS TOO FAR EAST...THOUGH NAM WOULD SUPPORT ACTIVITY OVER
MOST OF OUR CWA BY 00Z.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 225 PM MDT FRI JUL 12 2013
UPPER FLOW WILL BE IN TRANSITION SATURDAY NIGHT AS THE RIDGE SHIFTS
EAST AND A LOW RETROGRESSES WEST INTO THE MISSOURI RIVER VALLEY. THE
UPPER LOW WILL MOVE INTO THE SOUTHERN PLAINS BY SUNDAY EVENING AND
THE TEXAS PANHANDLE MONDAY. WEAK SURFACE LOW PRESSURE IS FORECAST TO
BE OVER EASTERN COLORADO/NEW MEXICO THROUGH SUNDAY. SURFACE HIGH
PRESSURE WILL RETROGRESS WEST INTO THE CENTRAL/SOUTHERN PLAINS
SUNDAY NIGHT AND MONDAY.
THE SURFACE TROUGH IN EASTERN COLORADO WILL SERVE AS A FOCUS FOR
THUNDERSTORM INITIATION SATURDAY EVENING AS THE NEXT IMPULSE COMES
THROUGH THE FLOW. MOISTURE IS LIMITED SO WILL STAY WITH A SLIGHT
CHANCE POP. DEEP EASTERLY FLOW WILL SET UP SUNDAY/SUNDAY NIGHT WITH
CONVERGENCE OVER THE HIGHER TERRAIN OF EASTERN COLORADO. THERE IS
GOOD LIFT OVER THE HIGHER TERRAIN SO PLAN TO GO WITH SLIGHT CHANCE
OVER MOST OF THE FA WITH CHANCE POPS OVER EASTERN COLORADO. FOR NOW
WILL KEEP MONDAY MORNING DRY BUT CANNOT RULE OUT SOME LINGERING
SHOWERS IN THE FAR WESTERN PORTIONS OF THE EASTERN COLORADO
ZONES. BY MONDAY AFTERNOON A SHORTWAVE AFFECTS THE SOUTHERN
FA AS IT ROTATES AROUND THE LOW INTO THE AREA. FOR NOW WILL GO WITH
SLIGHT CHANCE POPS FOR THIS FEATURE SINCE DYNAMICS ARE WEAK AND
TRANSITIONING WESTWARD.
TEMPERATURES ARE MORE CHALLENGING WITH 850 TEMPERATURES IN THE MID
20S INSTEAD OF THE MID 30S. AT THIS TIME MAX TEMPERATURES SUNDAY
WILL BE AROUND 90 WITH MID/UPPER 80S MONDAY. DEPENDING ON HOW MUCH
PRECIPITATION AND CLOUDS ARE AROUND COOLER MAX TEMPERATURES ARE
POSSIBLE. MIN TEMPERATURES WILL RANGE FROM THE UPPER 60S/LOWER 70S
SUNDAY NIGHT TO THE MID 60S MONDAY NIGHT.
IN THE EXTENDED...(MONDAY NIGHT THROUGH FRIDAY)...UPPER FLOW WILL BE
SOUTHEASTERLY WITH THE LOW OVER NEW MEXICO. THIS LOW WILL WEAKEN
WEDNESDAY NIGHT AND THURSDAY WITH A RIDGE BUILDING OVER THE PACIFIC
NORTHWEST FRIDAY. SURFACE HIGH PRESSURE WILL BE OVER THE REGION
MONDAY NIGHT. FROM TUESDAY THROUGH FRIDAY WEAK LOW PRESSURE WILL BE
OVER EASTERN COLORADO. NUMEROUS SHORTWAVES WILL COME THROUGH THE
FLOW PRODUCING AT LEAST A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS
ACROSS THE FA.
850 TEMPERATURES COOL TO THE UPPER TEENS AND MID 20S. THIS SHOULD
RESULT IN MAX TEMPERATURES RANGING FROM THE MID 80S TO AROUND 90.
MIN TEMPERATURES WILL RANGE IN THE 60S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1127 AM MDT FRI JUL 12 2013
VFR CONDITIONS WILL PREVAIL AT BOTH KGLD AND KMCK TERMINALS
THROUGH THE TAF PERIOD. A FEW HIGH BASED THUNDERSTORMS (12-14KFT)
WILL BE POSSIBLE THIS AFTERNOON AND EVENING OVER EASTERN
COLORADO...HOWEVER AT THIS TIME THIS ACTIVITY IS EXPECTED TO
REMAIN EAST OF BOTH TERMINALS. SOUTH WINDS 12-14KT WITH
OCCASIONAL GUSTS 20-25KT ARE EXPECTED AT BOTH TERMINALS THIS
AFTERNOON...WITH DECREASING WINDS OVERNIGHT AS TROUGH AXIS SHIFTS
EAST AND GRADIENT WEAKENS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR KSZ003-004-015-016.
CO...NONE.
NE...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NEZ080-081.
&&
$$
SHORT TERM...DR
LONG TERM...FS
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1255 PM MDT FRI JUL 12 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 1255 PM MDT FRI JUL 12 2013
LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOWS 593 DM RIDGE EXTENDING
ACROSS THE PLAINS INTO THE NORTHERN MISSISSIPPI VALLEY...WITH CLOSED
576 DM LOW OVER OHIO RIVER VALLEY DOWNSTREAM...AND TROUGH IN PLACE
ACROSS PACIFIC NORTHWEST. THIS RIDGE WILL KEEP VERY HOT TEMPS IN
PLACE THE NEXT FEW DAYS WITH MINIMAL PRECIP CHANCES.
IMMEDIATE CONCERN IS VERY HOT TEMPERATURES ACROSS THE AREA THIS
AFTERNOON. SOUTHERLY FLOW HAS KEPT TD VALUES AROUND 60F IN PLACE
ACROSS THE EASTERN PART OF OUR CWA...WHICH SHOULD SUPPORT HEAT
INDICES AROUND 105F DURING PEAK HEATING. THOUGH I COULD SEE THIS AS
A MARGINAL SITUATION...PER COORDINATION AND LOCAL GUIDANCE I WENT
AHEAD AND ISSUED AT HEAT ADVISORY THROUGH 00Z.
SHORT RANGE GUIDANCE CONTINUES TO SUPPORT THUNDERSTORM INITIATION
ALONG SURFACE TROUGH AXIS NEAR OUR CWA BORDER. WITHOUT LARGE SCALE
FORCING IN PLACE...THIS ACTIVITY WILL PROBABLY BE TIED TO PEAK
HEATING...WITH CHANCES QUICKLY DIMINISHING AFTER SUNSET. I WENT
AHEAD AND INCLUDED ISO THUNDER MENTION...THOUGH CONFIDENCE IS PRETTY
LOW. LCL VALUES ARE GENERALLY IN THE 12-14KFT RANGE AND WITH DEEP
DRY LAYER BELOW WE MAY NOT ACTUALLY SEE MUCH REGARDING MEASURABLE
PRECIP WITH ANY OF THESE STORMS THAT DO DEVELOP. WITH DCAPE IN
EXCESS OF 1500 J/KG IS ALSO FORECAST BY BOTH RAP AND NAM BY THIS
AFTERNOON...SO STRONG GUSTS ARE CERTAINLY POSSIBLE WITH THESE STORMS.
SURFACE TROUGH BEGINS TO SHIFT SOUTH AND EAST SATURDAY...WHICH COULD
ALLOW SLIGHTLY COOLER TEMPS (AT LEAST SUB 100F) TO MOVE INTO THE
NORTHWEST PART OF THE CWA. THIS COULD ALSO SHIFT SW FLOW FURTHER
SOUTH KEEPING TD VALUES LOWER WHERE HIGHEST TEMPS ARE...SO CHANCE
FOR HEAT INDICES AROUND 105 SEEMS MUCH LOWER. GUIDANCE IS STILL
SHOWING THUNDERSTORMS INITIATING IN THE EARLY AFTERNOON ALONG AND
BEHIND THIS TROUGH AXIS. IT LOOKS LIKE A VERY SIMILAR SITUATION AS
TODAY WITH LITTLE IN THE WAY OF FORCING BEYOND DESTABILIZATION ALONG
TROUGH AXIS IN THE AFTERNOON/EVENING. WE COULD SEE INITIATION FURTHER
EAST DEPENDING ON TROUGH LOCATION. AT THIS TIME I DECIDED AGAINST
EXPANDING POPS TOO FAR EAST...THOUGH NAM WOULD SUPPORT ACTIVITY OVER
MOST OF OUR CWA BY 00Z.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 338 AM MDT FRI JUL 12 2013
WELL IT LOOKS LIKE THE 11TH/00Z ECMWF WAS ONTO SOMETHING WHEN IT WAS
AGGRESSIVE IN BRINGING AN UPPER LOW AND MUCH COOLER TEMPS INTO THE
REGION EARLY NEXT WEEK AS ALL OTHER GLOBAL GUIDANCE HAS NOW CAUGHT
ON AS OF THE 12Z AND 18Z SUITES. TONIGHTS 00Z GUIDANCE CONTINUES TO
MOVE THE RETROGRADING UPPER LOW FROM THE SOUTHERN PLAINS TO EASTERN
COLORADO ON MONDAY INTO TUESDAY. STILL HAVE SOME MINOR CONCERN ABOUT
JUST HOW FAST THE LOW RETROGRADES FROM THE MID-ATLANTIC TO THE
SOUTHERN PLAINS...AND WOULD NOT BE SURPRISED TO SEE MODEL TREND
SLIGHTLY SLOWER OVER THE NEXT FEW DAYS.
WX IMPACTS FROM THE LOW WILL BE INCREASED POPS AND COOLER
TEMPS...WITH BEST CHANCE FOR STORMS ON MONDAY SOUTH OF I-70. EC/GFS
MOS GIVE SOME 20-25 POPS ON TUES AS WELL...BUT GIVEN THE FACT THAT
THE UPPER LOW WILL BE DISSIPATING DURING THIS TIME DO NOT HAVE
ENOUGH CONFIDENCE TO INCLUDE MENTION OF STORMS DURING THIS TIME
PERIOD...THOUGH COULD EASILY SEE LINGERING OUTFLOW/ SURFACE
BOUNDARIES FROM CONVECTION ON MONDAY PROVIDING A TRIGGER FOR
CONVECTION ON TUESDAY. ON TEMPS THE TREND CONTINUES DOWN...WITH EC
MOS HAVING HIGHS ON MONDAY IN THE MID 70S AND GFS MOS IN THE MID
80S...QUITE A DOWNTURN FROM THE MID 90S ALL GUIDANCE /INCLUDING EC
AND GFS MOS/ PREDICTED JUST A FEW DAYS AGO. REST OF WEEK LOOKS TO BE
BELOW TO NEAR NORMAL ON TEMPS /MID 80S TO 90S FOR HIGHS/ WITH SILENT
POPS AS LARGE SCALE PATTERN TRANSITIONS TO A WEAK RIDGE OVER THE
CENTRAL US.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1127 AM MDT FRI JUL 12 2013
VFR CONDITIONS WILL PREVAIL AT BOTH KGLD AND KMCK TERMINALS
THROUGH THE TAF PERIOD. A FEW HIGH BASED THUNDERSTORMS (12-14KFT)
WILL BE POSSIBLE THIS AFTERNOON AND EVENING OVER EASTERN
COLORADO...HOWEVER AT THIS TIME THIS ACTIVITY IS EXPECTED TO
REMAIN EAST OF BOTH TERMINALS. SOUTH WINDS 12-14KT WITH
OCCASIONAL GUSTS 20-25KT ARE EXPECTED AT BOTH TERMINALS THIS
AFTERNOON...WITH DECREASING WINDS OVERNIGHT AS TROUGH AXIS SHIFTS
EAST AND GRADIENT WEAKENS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR KSZ003-004-015-016.
CO...NONE.
NE...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NEZ080-081.
&&
$$
SHORT TERM...DR
LONG TERM...JJM
AVIATION...DR
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1230 PM CDT FRI JUL 12 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 320 AM CDT FRI JUL 12 2013
THE WEATHER PATTERN THIS MORNING DEPICTS THE MID LEVEL RIDGE AXIS
STRETCHING ACROSS THE CENTRAL AND NORTHERN PLAINS. THE RIDGE IS
EXPECTED TO EXPAND NORTHEASTWARD LATER TODAY ESSENTIALLY CUTTING OFF
THE FLOW FROM THE UPPER TROUGH ROTATING OVER THE MID ATLANTIC REGION.
AT THE 08Z HOUR A SUBTLE PERTURBATION EMBEDDED WITHIN THE RIDGE WAS
NOTED OVER SOUTHEAST WYOMING. THE LATEST HRRR AND RAP HAVE TRIED TO
GENERATE PRECIP FOR THE PREVIOUS FEW HOURS NOTING MULTIPLE WEAK
SHORTWAVE TROUGHS THAT ARE NOT OBSERVED IN REAL TIME. AND SINCE NO
FORCING IS APPARENT WILL THEREFORE MONITOR BUT MAINTAIN A DRY
FORECAST FOR THE MORNING PERIOD. A WARMER AND WINDY FRIDAY IS IN
STORE FOR NORTHEAST KANSAS. SURFACE HEATING AND A TIGHTENING
PRESSURE GRADIENT FROM THE H85 SHORTWAVE TROUGH OVER EASTERN
COLORADO WILL PICKUP SOUTHERLY WINDS BETWEEN FROM 15 TO 20 MPH.
THIS WILL ALSO INCREASE WARMER AIR FLOWING INTO THE AREA WITH
READINGS FROM THE LOW 90S IN EAST CENTRAL AREAS...TO THE UPPER 90S
OVER NORTH CENTRAL KS. MOISTURE ADVECTING NORTHWARD WILL KEEP
DEWPOINTS IN THE LOW TO MIDDLE 60S...TRANSLATING TO HEAT INDICES
BETWEEN 100 AND 105 DEGREES OVER NORTH CENTRAL KS. QUIET WEATHER
CONTINUES INTO FRIDAY EVENING WITH STEADY SOUTHEAST WINDS KEEPING
TEMPERATURES WARMER THAN THIS MORNING IN UPPER 60S TO MID 70S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 320 AM CDT FRI JUL 12 2013
FOR SATURDAY THROUGH SUNDAY NIGHT...THE MAIN FOCUS FOR THE
FORECAST IS A RETROGRADING CLOSED LOW MOVING FROM THE TN VALLEY
INTO THE SOUTHERN HIGH PLAINS. MODELS SEEM TO BE SLIGHTLY FASTER
WITH THE PROGRESSION OF THE CLOSED UPPER LOW AND BY SUNDAY NIGHT
HAVE IT OVER THE HIGH PLAINS. ALSO THE MAJORITY OF MODEL SOLUTIONS
TAKE THE UPPER LOW SOUTH OF THE FORECAST AREA WITH THE BETTER
LARGE SCALE FORCING OVER SOUTHERN KS AND OK. CURIOUSLY IT APPEARS
AS THOUGH THERE IS NOT MUCH MID LEVEL MOISTURE ACCOMPANYING THE
LOW WITH THE NAM AND GFS ACTUALLY SHOWING PWS DRYING WITH SURFACE
DEWPOINT TEMPS COOLING AS THE UPPER LOW APPROACHES. ADDITIONALLY
THE MID LEVEL LAPSE RATES ARE PRETTY CLOSE TO THE MOIST ADIABATIC
LAPSE RATE SO THERE IS LITTLE OR NO INSTABILITY ABOVE THE LCL. SO
IN GENERAL AM NOT OVERLY EXCITED ABOUT PRECIP CHANCES THROUGH THE
WEEKEND. WILL KEEP A SLIGHT CHANCE FOR SOME SHOWERS SUNDAY ACROSS
EAST CENTRAL KS THINKING THIS IS THE MOST LIKELY TIME FRAME FOR
THE UPPER LOW TO MOVE THROUGH SOUTHEAST KS. SINCE THERE DOES NOT
APPEAR TO BE ANY INSTABILITY...HAVE REMOVED THE MENTION OF THUNDER
FROM THE FORECAST FOR SUNDAY. HIGHS SHOULD BE TRENDING COOLER
THROUGH THE WEEKEND...ESPECIALLY FOR SUNDAY AS MODELS SHOW LOW
LEVEL COLD AIR ADVECTION FROM THE SOUTHEAST. HIGHS IN THE 90S FOR
SATURDAY SHOULD COOL INTO THE MID 80S TO AROUND 90 FOR SUNDAY.
LOWS WILL ALSO TREND COOLER WITH READINGS FOR SUNDAY MORNING
EXPECTED TO BE IN THE 60S AS SURFACE RIDGING FROM THE EAST
PERSISTS.
MONDAY THROUGH TUESDAY IS A LITTLE MORE UNCERTAIN AS MODELS START
TO DIVERGE ON THE TRACK OF THE CLOSED LOW. THERE IS THE
POSSIBILITY THAT THE UPPER LOW GETS HUNG UP OVER THE HIGH PLAINS
WITH PIECES OF ENERGY ROTATING NORTH INTO THE STATE. BECAUSE OF
THIS HAVE HELD ONTO SOME SLIGHT CHANCE POPS DURING THE DAY MONDAY
AND TUESDAY THINKING THERE COULD BE SOME POP UP STORMS IF THE
UPPER LOW IS JUST TO THE WEST OF THE FORECAST AREA. HIGHS ARE
FORECAST TO REMAIN NEAR NORMAL WITH READINGS AROUND 90. SOUTHERLY
WINDS AND A GRADUAL INCREASE IN LOW LEVEL MOISTURE SHOULD KEEP
LOWS AROUND 70 TO THE LOWER 70S.
THE GFS AND ECMWF SHOW WEAK MID LEVEL RIDGING NOSING INTO EASTERN
KS FROM THE EAST WITH NO REAL SURFACE FEATURE TO FOCUS LIFT OF A
SURFACE PARCEL. BECAUSE OF THIS HAVE MAINTAINED A DRY FORECAST.
TEMPS SHOULD SEE A GRADUAL WARMING TREND AS MID LEVEL HEIGHTS
RISE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1229 PM CDT FRI JUL 12 2013
FOR THE 18Z TAFS...VFR CONDITIONS EXPECTED THROUGH THE PERIOD. WINDS
THROUGH THE PERIOD WILL REMAIN LIGHT OUT OF THE SOUTHEAST WITH MID
LEVEL CLOUDS BUILDING INTO THE REGION BY SATURDAY MORNING.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BOWEN
LONG TERM...WOLTERS
AVIATION...HENNECKE
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
650 PM EDT FRI JUL 12 2013
.SYNOPSIS...
COLD FRONT HAS STALLED ALONG THE COAST THIS AFTERNOON AND WILL
REMAIN OVER THE REGION THROUGH SATURDAY. HIGH PRESSURE WILL BUILD
INTO THE REGION FROM THE EAST THIS WEEKEND AS THE FRONT DISSIPATES
OVER THE AREA. HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH
EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
UPDATED TO REMOVE CENTRAL VA FROM THE FLASH FLOOD WATCH AS THE
THREAT FOR HEAVY RAINFALL HAS ENDED. FOR THE REMAINDER OF THE
WATCH AREA...A FEW ISOLATED AREAS OF HEAVY RAIN REMAIN POSSIBLE
THROUGH THE EVENING...BUT THE OVERALL THREAT IS QUICKLY
DIMINISHING.
PREVIOUS DISCUSSION...
PER LATEST MSAS ANALYSIS AND SFC OBSERVATIONS...COLD FRONT HAS
STALLED ACROSS SE VA THIS AFTERNOON. LATEST WATER VAPOR IMAGERY
CONTINUES TO SHOW PLUME OF MOISTURE LIFTING THROUGH THE REGION AS
LOW PRESSURE TO THE WEST SLOWLY DRIFTS SWD. LOW POSITION WILL
CONTINUE TO BE IN A FAVORABLE POSITION FOR STRONG UPPER LEVEL
FORCING (STRONG DIFFLUENCE ALOFT) OVER THE LOCAL AREA. SEEING
COOLING CLOUD TOPS OVER CNTRL/ERN NC ATTM AS A SHORT WAVE LIFTS
FROM THE SE. EXPECT ANOTHER WAVE OF SHOWERS AND EMBEDDED
THUNDERSTORMS TO LIFT NWD ALONG THE FRONT INTO NE NC/SE VA THROUGH
6 PM AND INTO ERN VA (MAINLY EAST OF INTERSTATE 95) THROUGH EARLY
TONIGHT. HAVE OPTED TO DROP HEADLINES OVER THE PIEDMONT AS DRY AIR
HAS WORKED IN ALOFT. LATEST RADAR TRENDS AND HRRR RUNS BACK THIS
UP WELL. HAVE ALSO EXTENDED FLASH FLOOD WATCH HEADLINES UNTIL
MIDNIGHT TONIGHT ALONG AND EAST OF INTERSTATE 95 TO ACCOUNT FOR
THE NEXT WAVE AND SATURATED SOILS. EXPECT THE WAVE TO LIFT
THROUGH THE LOCAL AREA BY MIDNIGHT...BUT SHOWERS EXPECTED TO
CONTINUE ALONG THE FRONT OVER SE VA/NE NC THROUGH LATE TONIGHT.
TEMPS EXPECTED TO FALL INTO THE UPPER 60S/LOW 70S TONIGHT UNDER
CLOUDY SKIES.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY NIGHT/...
MODELS CONTINUE TO HANDLE THE MID/UPPER LEVEL PATTERN WELL
THROUGH THE SHORT TERM. THE UPPER LOW WILL BECOME CUT OFF FROM THE
FLOW TONIGHT/SAT MORNING...AS HIGH PRESSURE STRENGTHENS OVER THE
CNTRL CONUS. THE LOW IS THEN PROGGED TO UNDERCUT THE
RIDGE...PROGRESSING SWWD THROUGH THE SHORT TERM TOWARD THE SRN
PLAINS. THIS WILL ALLOW UPPER/SFC HIGH PRESSURE TO BUILD INTO THE
REGION SAT...AND REMAINING CENTERED OVER THE OH VALLEY THROUGH THE
SHORT TERM. THE RESULT OVER THE LOCAL AREA WILL BE SUMMER LIKE
CONDITIONS WITH THE STORM TRACK REMAINING WELL TO THE NORTH OF THE
REGION. MOISTURE PLUME WILL MOVE INLAND AS UPPER LEVEL FLOW
BECOMES SELY SAT...WITH BEST POPS ACROSS THE PIEDMONT SAT
AFTERNOON. WHILE FORCING FOR ASCENT WILL BE SUBTLE...DIURNAL
FORCING AND ABUNDANT MOISTURE WILL RESULT IN SCATTERED SHOWERS AND
THUNDERSTORMS SAT AFTERNOON...WEST OF INTERSTATE 95. WILL KEEP
MENTION OF SLIGHT CHANCE POPS FOR THE PIEDMONT SUN AFTERNOON...BUT
BEST MOISTURE/DYNAMICS LOOKS TO BE WEST OF THE AREA. AREA WILL BE
UNDER THE INFLUENCE OF HIGH PRESSURE MON...BUT DO EXPECT MOISTURE
TO ADVECT FROM THE WRN ATLANTIC INTO THE REGION. PRESENCE OF A
WEAK LEE SIDE TROUGH AND SEA BREEZE BOUNDARIES UNDER WEAK FLOW
ALOFT...MAY RESULT IN ISOLATED-WIDELY SCATTERED THUNDERSTORMS
ACROSS THE LOCAL AREA. WILL MAINTAIN SLIGHT CHANCE POPS DURING THE
AFTERNOON FOR DIURNAL FORCING.
NEAR SEASONABLE NORMAL TEMPS SAT UNDER CLEARING SKIES FROM E TO
W. WARMING TREND WILL COMMENCE SUN AS STRONG HEIGHT RISES AND
INCREASING LOW LEVEL THICKNESS VALUES PUSH TEMPS INTO THE LOW 90S.
HOWEVER...SE FLOW WILL PREVENT TEMPS FROM REACHING THEIR FULL
POTENTIAL (HIGHS GENERALLY IN THE LOW 90S). SLIGHTLY WARMER MONDAY
AS WINDS BECOME MORE SLY (HIGHS IN THE LOW 90S). TEMPS ALONG THE
COAST DURING THE SHORT TERM WILL BE SLIGHTLY COOLER.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
HOTTER AND DRIER WEATHER EXPECTED NEXT WEEK...
MODELS ARE IN GOOD AGREEMENT SHOWING A STRONG H5 RIDGE (599DM)
RESIDING OVER THE OHIO VALLEY TUESDAY/WEDNESDAY OF NEXT WEEK. THE
RIDGE THEN SLOWLY SHIFTS EAST OVER THE MID-ATLANTIC REGION THURSDAY
BEFORE MOVING EAST TO OFF THE CAROLINA COAST BY NEXT FRIDAY. THE
POSITION AND STRENGTH OF THIS RIDGE POINTS TO A SPELL OF HOT WEATHER
ACROSS THE LOCAL AREA NEXT WEEK WITH MAX TEMPS RUNNING ABOUT 1
STANDARD DEVIATION ABOVE NORMAL (MID 90S). THIS STAGNANT AIRMASS
WILL ALSO RESULT IN WARM/MUGGY NIGHTS WITH LOWS IN THE MID/UPR 70S.
LITTLE OPPORTUNITY FOR PCPN WILL OCCUR IN THIS PATTERN AS WELL
OUTSIDE OF ISOLD CONVECTION OVER THE HIGHER TERRAIN TO OUR WEST OUR
ALONG THE AFTN SEA BREEZE. WILL GO NO HIGHER THAN SLIGHT CHC (20%)
POPS THROUGH THE PERIOD.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
A WEAK STNRY FRONT LINGERS OVER EASTERN VA AND NC WHERE MOST OF
THE PRECIP HAS CONTD THRU THIS MORNING AND EARLY AFTN. ANOTHER
AREA OF RAIN IS MOVG NORTH THRU EASTERN NC AND WILL AFFECT SE VA
DURING THE AFTN/EVENING PERIOD. RADAR SHOWS SOME LIGHTNING WITH
THIS ACTIVITY SO HAVE INCLUDED TSTMS IN TAFS AT ECG/ORF/PHF. HRRR
PRECIP MODEL SHOWS PRECIP AFFECTING SE VA/NE NC THRU 00Z. FRONT
WILL LIKELY REMAIN STNRY OVERNIGHT OR EVEN DISSIPATE. SFC WINDS
WILL DEPEND ON FRONT AND PRECIP BUT WILL GENERALLY BE LESS THAN 10
KT. CIGS WILL VARY BETWEEN MVFR AND VFR...BUT TEMPO IFR CONDS PSBL
WITH PRECIP. OVERNIGHT CIGS EXPECTED TO LOWER TO MVFR/IFR CONDS
WITH SOME MVFR VSBY DUE TO FOG. HI PRES EXPECTED TO GRADUALLY
BUILD INTO THE REGION ON SAT BUT SOME WIDELY SCTD SHOWERS STILL
PSBL EARLY.
&&
.MARINE...
NO HEADLINES EXPECTED THRU AT LEAST THIS WEEKEND. A FRONTAL BOUNDARY
WILL REMAIN STALLED OVER THE DELMARVA INTO SE VA THROUGH SAT BEFORE
DISSIPATING LATE IN THE DAY. WINDS WILL BE HIGHLY VARIABLE BUT LIGHT
ON THE CHES BAY THROUGH TONIGHT DUE TO THE LOCATION OF THE STALLED
FRONT. MEANWHILE...S-SE WINDS BETWEEN 10-15 KT WILL BE FOUND ON THE
COASTAL WATERS. BY SAT...THE DISSIPATING FRONT WILL ALLOW FOR S-SE
WINDS 10-15 KT ALL WATERS WITH A FEW GUSTS TO 20 KT POSSIBLE ACROSS
THE SOUTHERN COASTAL WATERS AND THE CURRITUCK SOUND. WAVES WILL
REMAIN 1-2 FT WITH SEAS 2-3 FT THROUGH SAT.
LATE SAT INTO THE MIDDLE OF NEXT WEEK...HIGH PRES WILL BUILD INTO
AND OVER THE MID-ATLANTIC REGION. THIS WILL RESULT IN GENERALLY S-SW
WINDS LESS THAN 15 KT. WAVES ON THE CHES BAY WILL CONTINUE TO
AVERAGE 1 TO 2 FT...WITH SEAS 2 TO 3 FT ON THE OCEAN.
&&
.HYDROLOGY...
SEVERAL ROUNDS OF HEAVY RAINFALL HAS RESULTED IN RAPID RISES IN
LOCAL RIVERS AND STREAMS. FLOOD WARNINGS ARE CURRENTLY IN EFFECT
FOR THE APPOMATTOX RIVER AT FARMVILLE AND MATTOAX WHERE MINOR
FLOODING IS FORECAST. HEAVY RAINFALL OVER THE UPPER JAMES BASIN
COULD PRODUCE MINOR FLOODING ALONG THE JAMES RIVER AT RICHMOND
WESTHAM DURING THE DAY SATURDAY.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR MDZ021>025.
NC...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR NCZ012>017-
030>032-102.
VA...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR VAZ077-078-
084>100.
MARINE...NONE.
&&
$$
SYNOPSIS...ESS/SAM
NEAR TERM...SAM/AJZ
SHORT TERM...SAM
LONG TERM...JDM
AVIATION...TMG/JEF
MARINE...JDM
HYDROLOGY...AKQ
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
413 PM EDT FRI JUL 12 2013
.SYNOPSIS...
COLD FRONT HAS STALLED ALONG THE COAST THIS AFTERNOON AND WILL
REMAIN OVER THE REGION THROUGH SATURDAY. HIGH PRESSURE WILL BUILD
INTO THE REGION FROM THE EAST THIS WEEKEND AS THE FRONT DISSIPATES
OVER THE AREA. HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH
EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
PER LATEST MSAS ANALYSIS AND SFC OBSERVATIONS...COLD FRONT HAS
STALLED ACROSS SE VA THIS AFTERNOON. LATEST WATER VAPOR IMAGERY
CONTINUES TO SHOW PLUME OF MOISTURE LIFTING THROUGH THE REGION AS
LOW PRESSURE TO THE WEST SLOWLY DRIFTS SWD. LOW POSITION WILL
CONTINUE TO BE IN A FAVORABLE POSITION FOR STRONG UPPER LEVEL
FORCING (STRONG DIFFLUENCE ALOFT) OVER THE LOCAL AREA. SEEING
COOLING CLOUD TOPS OVER CNTRL/ERN NC ATTM AS A SHORT WAVE LIFTS
FROM THE SE. EXPECT ANOTHER WAVE OF SHOWERS AND EMBEDDED
THUNDERSTORMS TO LIFT NWD ALONG THE FRONT INTO NE NC/SE VA THROUGH
6 PM AND INTO ERN VA (MAINLY EAST OF INTERSTATE 95) THROUGH EARLY
TONIGHT. HAVE OPTED TO DROP HEADLINES OVER THE PIEDMONT AS DRY AIR
HAS WORKED IN ALOFT. LATEST RADAR TRENDS AND HRRR RUNS BACK THIS
UP WELL. HAVE ALSO EXTENDED FLASH FLOOD WATCH HEADLINES UNTIL
MIDNIGHT TONIGHT ALONG AND EAST OF INTERSTATE 95 TO ACCOUNT FOR
THE NEXT WAVE AND SATURATED SOILS. EXPECT THE WAVE TO LIFT
THROUGH THE LOCAL AREA BY MIDNIGHT...BUT SHOWERS EXPECTED TO
CONTINUE ALONG THE FRONT OVER SE VA/NE NC THROUGH LATE TONIGHT.
TEMPS EXPECTED TO FALL INTO THE UPPER 60S/LOW 70S TONIGHT UNDER
CLOUDY SKIES.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY NIGHT/...
MODELS CONTINUE TO HANDLE THE MID/UPPER LEVEL PATTERN WELL
THROUGH THE SHORT TERM. THE UPPER LOW WILL BECOME CUT OFF FROM THE
FLOW TONIGHT/SAT MORNING...AS HIGH PRESSURE STRENGTHENS OVER THE
CNTRL CONUS. THE LOW IS THEN PROGGED TO UNDERCUT THE
RIDGE...PROGRESSING SWWD THROUGH THE SHORT TERM TOWARD THE SRN
PLAINS. THIS WILL ALLOW UPPER/SFC HIGH PRESSURE TO BUILD INTO THE
REGION SAT...AND REMAINING CENTERED OVER THE OH VALLEY THROUGH THE
SHORT TERM. THE RESULT OVER THE LOCAL AREA WILL BE SUMMER LIKE
CONDITIONS WITH THE STORM TRACK REMAINING WELL TO THE NORTH OF THE
REGION. MOISTURE PLUME WILL MOVE INLAND AS UPPER LEVEL FLOW
BECOMES SELY SAT...WITH BEST POPS ACROSS THE PIEDMONT SAT
AFTERNOON. WHILE FORCING FOR ASCENT WILL BE SUBTLE...DIURNAL
FORCING AND ABUNDANT MOISTURE WILL RESULT IN SCATTERED SHOWERS AND
THUNDERSTORMS SAT AFTERNOON...WEST OF INTERSTATE 95. WILL KEEP
MENTION OF SLIGHT CHANCE POPS FOR THE PIEDMONT SUN AFTERNOON...BUT
BEST MOISTURE/DYNAMICS LOOKS TO BE WEST OF THE AREA. AREA WILL BE
UNDER THE INFLUENCE OF HIGH PRESSURE MON...BUT DO EXPECT MOISTURE
TO ADVECT FROM THE WRN ATLANTIC INTO THE REGION. PRESENCE OF A
WEAK LEE SIDE TROUGH AND SEA BREEZE BOUNDARIES UNDER WEAK FLOW
ALOFT...MAY RESULT IN ISOLATED-WIDELY SCATTERED THUNDERSTORMS
ACROSS THE LOCAL AREA. WILL MAINTAIN SLIGHT CHANCE POPS DURING THE
AFTERNOON FOR DIURNAL FORCING.
NEAR SEASONABLE NORMAL TEMPS SAT UNDER CLEARING SKIES FROM E TO
W. WARMING TREND WILL COMMENCE SUN AS STRONG HEIGHT RISES AND
INCREASING LOW LEVEL THICKNESS VALUES PUSH TEMPS INTO THE LOW 90S.
HOWEVER...SE FLOW WILL PREVENT TEMPS FROM REACHING THEIR FULL
POTENTIAL (HIGHS GENERALLY IN THE LOW 90S). SLIGHTLY WARMER MONDAY
AS WINDS BECOME MORE SLY (HIGHS IN THE LOW 90S). TEMPS ALONG THE
COAST DURING THE SHORT TERM WILL BE SLIGHTLY COOLER.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
HOTTER AND DRIER WEATHER EXPECTED NEXT WEEK...
MODELS ARE IN GOOD AGREEMENT SHOWING A STRONG H5 RIDGE (599DM)
RESIDING OVER THE OHIO VALLEY TUESDAY/WEDNESDAY OF NEXT WEEK. THE
RIDGE THEN SLOWLY SHIFTS EAST OVER THE MID-ATLANTIC REGION THURSDAY
BEFORE MOVING EAST TO OFF THE CAROLINA COAST BY NEXT FRIDAY. THE
POSITION AND STRENGTH OF THIS RIDGE POINTS TO A SPELL OF HOT WEATHER
ACROSS THE LOCAL AREA NEXT WEEK WITH MAX TEMPS RUNNING ABOUT 1
STANDARD DEVIATION ABOVE NORMAL (MID 90S). THIS STAGNANT AIRMASS
WILL ALSO RESULT IN WARM/MUGGY NIGHTS WITH LOWS IN THE MID/UPR 70S.
LITTLE OPPORTUNITY FOR PCPN WILL OCCUR IN THIS PATTERN AS WELL
OUTSIDE OF ISOLD CONVECTION OVER THE HIGHER TERRAIN TO OUR WEST OUR
ALONG THE AFTN SEA BREEZE. WILL GO NO HIGHER THAN SLIGHT CHC (20%)
POPS THROUGH THE PERIOD.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
A WEAK STNRY FRONT LINGERS OVER EASTERN VA AND NC WHERE MOST OF
THE PRECIP HAS CONTD THRU THIS MORNING AND EARLY AFTN. ANOTHER
AREA OF RAIN IS MOVG NORTH THRU EASTERN NC AND WILL AFFECT SE VA
DURING THE AFTN/EVENING PERIOD. RADAR SHOWS SOME LIGHTNING WITH
THIS ACTIVITY SO HAVE INCLUDED TSTMS IN TAFS AT ECG/ORF/PHF. HRRR
PRECIP MODEL SHOWS PRECIP AFFECTING SE VA/NE NC THRU 00Z. FRONT
WILL LIKELY REMAIN STNRY OVERNIGHT OR EVEN DISSIPATE. SFC WINDS
WILL DEPEND ON FRONT AND PRECIP BUT WILL GENERALLY BE LESS THAN 10
KT. CIGS WILL VARY BETWEEN MVFR AND VFR...BUT TEMPO IFR CONDS PSBL
WITH PRECIP. OVERNIGHT CIGS EXPECTED TO LOWER TO MVFR/IFR CONDS
WITH SOME MVFR VSBY DUE TO FOG. HI PRES EXPECTED TO GRADUALLY
BUILD INTO THE REGION ON SAT BUT SOME WIDELY SCTD SHOWERS STILL
PSBL EARLY.
&&
.MARINE...
NO HEADLINES EXPECTED THRU AT LEAST THIS WEEKEND. A FRONTAL BOUNDARY
WILL REMAIN STALLED OVER THE DELMARVA INTO SE VA THROUGH SAT BEFORE
DISSIPATING LATE IN THE DAY. WINDS WILL BE HIGHLY VARIABLE BUT LIGHT
ON THE CHES BAY THROUGH TONIGHT DUE TO THE LOCATION OF THE STALLED
FRONT. MEANWHILE...S-SE WINDS BETWEEN 10-15 KT WILL BE FOUND ON THE
COASTAL WATERS. BY SAT...THE DISSIPATING FRONT WILL ALLOW FOR S-SE
WINDS 10-15 KT ALL WATERS WITH A FEW GUSTS TO 20 KT POSSIBLE ACROSS
THE SOUTHERN COASTAL WATERS AND THE CURRITUCK SOUND. WAVES WILL
REMAIN 1-2 FT WITH SEAS 2-3 FT THROUGH SAT.
LATE SAT INTO THE MIDDLE OF NEXT WEEK...HIGH PRES WILL BUILD INTO
AND OVER THE MID-ATLANTIC REGION. THIS WILL RESULT IN GENERALLY S-SW
WINDS LESS THAN 15 KT. WAVES ON THE CHES BAY WILL CONTINUE TO
AVERAGE 1 TO 2 FT...WITH SEAS 2 TO 3 FT ON THE OCEAN.
&&
.HYDROLOGY...
SEVERAL ROUNDS OF HEAVY RAINFALL HAS RESULTED IN RAPID RISES IN
LOCAL RIVERS AND STREAMS. FLOOD WARNINGS ARE CURRENTLY IN EFFECT
FOR THE APPOMATTOX RIVER AT FARMVILLE AND MATTOAX WHERE MINOR
FLOODING IS FORECAST. HEAVY RAINFALL OVER THE UPPER JAMES BASIN
WILL ALSO LIKELY RESULT IN MINOR FLOODING ALONG THE JAMES RIVER AT
RICHMOND WESTHAM DURING THE DAY SATURDAY.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR MDZ021>025.
NC...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR NCZ012>017-
030>032-102.
VA...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR VAZ063-064-
070>100.
MARINE...NONE.
&&
$$
SYNOPSIS...SAM
NEAR TERM...SAM
SHORT TERM...SAM
LONG TERM...JDM
AVIATION...TMG/JEF
MARINE...JDM
HYDROLOGY...SAM
AREA FORECAST DISCUSSION
NWS HASTINGS NE
123 PM CDT FRI JUL 12 2013
.UPDATE...
ISSUED AT 123 PM CDT FRI JUL 12 2013
TEMPERATURES RANGING FROM 97 TO 105 DEGREES COUPLED WITH DEWPOINTS
IN THE MID 60S WILL RESULT IN HEAT INDICES TOPPING OUT BETWEEN 103
AND 106 DEGREES ACROSS PORTIONS OF NORTH CENTRAL KANSAS. A HEAT
ADVISORY WILL BE IN EFFECT THIS AFTERNOON UNTIL 7 PM THIS
EVENING FOR PHILLIPS...ROOKS...OSBORNE...AND MITCHELL COUNTIES IN
KANSAS.
UPDATE ISSUED AT 925 AM CDT FRI JUL 12 2013
THE BIG CHANGE MADE DURING THIS UPDATE WAS HIGH TEMPERATURES FOR
LATER THIS AFTERNOON. BASED ON CURRENT TRENDS...NEW DATA...AND
VERIFICATION STATISTICS...I LOWERED HIGHS THIS AFTERNOON FOR MOST
OF OUR NEBRASKA COUNTIES. THIS WAS NOT A DRASTIC CHANGE...BUT
MOST LOCATIONS WERE LOWERED TWO TO THREE DEGREES. PHILLIPS AND
ROOKS COUNTIES IN KANSAS WERE ACTUALLY RAISED A DEGREE OR
TWO...OTHERWISE...TEMPERATURES ACROSS KANSAS STAYED RELATIVELY
CLOSE TO THE PREVIOUS FORECAST. DEW POINTS WERE ALSO UPDATED TO
REFLECT TRENDS AND NEW DATA.
UPDATE ISSUED AT 635 AM CDT FRI JUL 12 2013
THE NARROW LINE OF ACCAS-INDUCED SPRINKLES/SHOWERS THAT EARLIER
STARTED TO DEVELOP WITHIN THE EASTERN FRINGES OF THE CWA HAS SINCE
ADVECTED 1+ COUNTY EAST OF OUR AREA PER THE LATEST RADAR/SATELLITE
TRENDS. THUS WILL FORGE AHEAD WITH NO PRECIP MENTION WHATSOEVER
THROUGH THE NEXT 24 HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 431 AM CDT FRI JUL 12 2013
THE PRIMARY ISSUE DURING THE NEXT 24 HOURS IS DETERMINING HOW HOT
WE ACTUALLY GET TODAY/HOW CLOSE WE GET TO HEAT ADVISORY
CRITERIA...AND HOW CLOSE TO CRITICAL FIRE DANGER WESTERN PARTS OF
NORTH CENTRAL KANSAS MIGHT GET. ALTHOUGH THE FORECAST PRODUCTS
CARRY NO MENTION OF SHOWERS/THUNDERSTORMS DUE TO POPS HOLDING BELOW
15 PERCENT...POPS ARE NOT NECESSARILY ZERO...AND WILL HAVE TO KEEP
AN EYE ESPECIALLY ON FAR WESTERN/NORTHERN COUNTIES LATE THIS
AFTERNOON-TONIGHT FOR THE REMOTE CHANCE THAT A FEW STORMS COULD
POP UP OR MOVE IN FROM THE WEST/NORTH. IN THE IMMEDIATE NEXT FEW
HOURS...ITS NOT COMPLETELY OUT OF THE QUESTION THAT A FEW HIGH-
BASED SHOWERS/STORMS COULD TRY DEVELOPING IN EASTERN ZONES BEFORE
SUNRISE.
08Z OBJECTIVE SURFACE ANALYSIS REVEALS A FAIRLY ILL-DEFINED QUASI-
STATIONARY FRONT SNAKING FROM A 1000 MILLIBAR LOW IN NORTHWEST
SD...SOUTHWARD THROUGH WESTERN NEBRASKA INTO NORTHWEST/SOUTH CENTRAL
KS. OFF TO THE EAST...A 1019MB HIGH IS CENTERED NEAR THE IA/IL
BORDER. BETWEEN THE FRONT AND THE HIGH...FAIRLY STEADY SOUTH-
SOUTHEAST BREEZES OF 8-15 MPH WITH OCCASIONAL GUSTS OVER 20 ARE IN
PLACE ACROSS THE CWA EARLY THIS MORNING...WITH THESE BREEZES
EXPECTED TO HELP HOLD LOW TEMPS UP BETWEEN 69-74 IN MOST AREAS.
ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA HIGHLIGHT A
FAIRLY EXPANSIVE MID/UPPER LEVEL RIDGE AXIS THAT HAS BUILT
NORTHEAST SINCE 24 HOURS AGO TO ENCOMPASS MUCH OF THE
CENTRAL/SOUTH CENTRAL CONUS. THE CENTER AXIS OF THIS RIDGE...AT
ROUGHLY 590 DECAMETER...RUNS FROM ROUGHLY THE LOCAL CWA ON THE
NORTHEAST EDGE...BACK SOUTHWESTWARD TOWARD THE NM/TX BORDER. WITH
THIS RIDGE AXIS NEARLY OVERHEAD...THE FLOW OVER THE CWA AT 500MB
IS FAIRLY LIGHT/VARIABLE...WHILE A BIT LOWER AT 700MB...THERE IS
MODEST WEST-SOUTHWEST FLOW. A NARROW ZONE OF THETA-E ADVECTION
ALONG A FAIRLY TIGHT 700MB MOISTURE GRADIENT HAS RESULTED IN A
SCATTERED ACCAS FIELD WITHIN ROUGHLY THE EASTERN 1/3 OF THE CWA
TONIGHT...AND RECENTLY THE FIRST FEW HINTS OF ISOLATED ELEVATED
SPRINKLES/LIGHT SHOWERS HAVE SHOWED UP ON RADAR WITHIN A FEW OF
OUR EASTERN COUNTIES.
STARTING WITH THE MOST IMMEDIATE ISSUE...WILL BE CLOSELY
MONITORING RADAR TRENDS IN EASTERN ZONES PRIOR TO SUNRISE TO SEE
WHETHER THE AFOREMENTIONED VERY ISOLATED CONVECTION CAN BE COVERED
WITH A SPRINKLE MENTION...OR MIGHT NEED SOMETHING MORE.
THE LATEST RAP HAS CAUGHT ONTO THIS DEVELOPMENT...AND SUGGESTS
THAT MAINLY OUR FAR EASTERN COUNTIES NEAR THE HWY 81 CORRIDOR
COULD CONTINUE TO SEE SOME OF THIS PRE-DAWN ACTIVITY...BUT THAT IT
SHOULD LARGELY BE DONE OR ADVECTED EAST OF THE CWA BY 7AM/12Z. PER
FORECAST SOUNDINGS...PARCELS ROOTED NEAR 700MB COULD POTENTIALLY
HAVE UP TO AROUND 400 J/KG MUCAPE AVAILABLE TO THEM...SO A BRIEF
FLARE UP OF NON-SEVERE THUNDERSTORMS IS NOT COMPLETELY OUT OF THE
QUESTION. FOR NOW...WILL ONLY MENTION ISOLATED SPRINKLES IN OUR
EASTERN FEW COLUMNS OF NEBRASKA COUNTIES THROUGH 12Z TO COVER
THINGS...PENDING ANY EVIDENCE OTHERWISE.
TURNING TO THE DAYTIME HOURS...THE MAIN STORY WILL BE A RETURN OF
LEGITIMATE SUMMER HEAT...BUT DOES NOT APPEAR TO BE HEADLINE-
WORTHY. IN THE MID/UPPER LEVELS...THE DOMINANT RIDGE AXIS WILL
CONTINUE TO EXPAND ACROSS THE CENTRAL PLAINS IN A SOUTHWEST-
NORTHEAST FASHION...WITH PARTS OF THE CWA ALIGNED ALMOST DIRECTLY
UNDER ITS CENTER AXIS. AT THE SURFACE...A FAIRLY SHARP TROUGH
AXIS WILL SET UP FROM FAR EASTERN CO ACROSS NORTHWEST NEB INTO
CENTRAL SD BY MID-LATE AFTERNOON...EXTENDING FROM A ROUGHLY 1000MB
LOW CENTERED NEAR THE CO/KS BORDER. THE LOCAL CWA WILL REMAIN IN
THE OPEN WARM SECTOR SOLIDLY SOUTHEAST OF THIS TROUGH AXIS...AND
THUS WILL SEE A CONTINUATION OF FAIRLY BREEZY SOUTH-SOUTHEAST
WINDS...WITH SUSTAINED SPEEDS MOST ALL AREAS 15-20 MPH AND GUSTS
25 TO POSSIBLY 30 MPH AT TIMES. AS FOR CONVECTIVE CHANCES...ASIDE
FROM ANY EARLY MORNING ACTIVITY IN THE EAST...THERE IS LITTLE IF
ANY RISK OF SHOWERS/STORMS TODAY AS WARM MID LEVEL TEMPS WITHIN
THE RIDGE AXIS SHOULD SERVE TO CAP THINGS OFF PRETTY SOLIDLY. ONE
OF THE ONLY POSSIBLE CAVEATS...AS DEPICTED BY THE LATEST RAP
RUNS...IS THAT STRONG HEATING AND VERY DEEP MIXING COULD POP A FEW
HIGH-BASED STORMS LATE IN THE AFTERNOON ALONG WESTERN PORTIONS OF
THE NEB/KS BORDER...WITH SOME OF THIS ACTIVITY POSSIBLY ADVECTING
EAST INTO THE DAWSON-FURNAS COUNTY CORRIDOR...BUT THE ODDS OF THIS
SEEM LOW ENOUGH TO STICK WITH SILENT 10 POPS FOR NOW...AS MOST
LATE AFTERNOON STORMS SHOULD FOCUS WELL TO OUR NORTHWEST ALONG THE
AFOREMENTIONED TROUGH AXIS. TEMP-WISE...BASED ON HOW HIGHS TURNED
OUT YESTERDAY...IT APPEARS THE NAM AND ASSOCIATED MET GUIDANCE HAS
BEEN A BIT AGGRESSIVE WITH THE HEAT...AND AS A RESULT...HAVE
SHAVED A FEW DEGREES OFF HIGHS TODAY IN MOST AREAS...USING VALUES
A BIT CLOSER TO GFS MAV GUIDANCE AND A MULTI-MODEL BLEND. THIS STILL
YIELDS A VERY TOASTY DAY WITH HIGHS RANGING FROM MID 90S NORTHEAST
...MID-UPPER 90S CENTRAL AND UPPER 90S TO AROUND 102 IN KS ZONES
AND NEAR THE STATE LINE. AS FOR DEWPOINTS...NOT EXPECTING A
DRAMATIC MIX-DOWN TODAY GIVEN THAT WINDS WILL BE MORE SOUTHERLY
VERSUS SOUTHWESTERLY...BUT NUDGED THEM DOWN A BIT ESPECIALLY IN
WESTERN ZONES...RANGING FROM UPPER 50S AT MID-AFTERNOON IN THE FAR
WEST TO MID-UPPER 60S IN THE EAST. THE RESULTANT HEAT INDEX VALUES
PEAK IN THE 98-100 RANGE ACROSS MOST OF THE NEB CWA...WITH KS
ZONES AND AREAS NEAR THE STATE LINE MORE LIKELY TO REACH THE
101-104 RANGE. BOTTOM LINE HERE IS...THESE VALUES ARE CERTAINLY
WORTH A HAZARDOUS WEATHER OUTLOOK MENTION...BUT DO NOT JUSTIFY A
FORMAL HEAT ADVISORY BASED ON OUR 105+ LOCAL CRITERIA. PLEASE NOTE
THAT THE NORTH PLATTE/LBF CWA HAS A SLIGHTLY COOLER
...CLIMATOLOGICALLY-BASED HEAT ADVISORY CRITERIA OF 100+...AND
THIS IS WHY A FORMAL HEADLINE IS OUT FOR THEIR AREA...BUT NOT FOR
OURS.
TURNING TO THIS EVENING/TONIGHT POST-7PM/00Z...THE MAIN STORY
VERSUS PREVIOUS FORECAST IS THAT THE SLIGHT CHANCE OF
THUNDERSTORMS HAS BEEN TRIMMED FROM THE EXTREME NORTHERN/WEST-
CENTRAL EDGES OF THE CWA...AND THUS WILL CARRY A STORM-FREE
FORECAST CWA-WIDE. AGAIN THOUGH...WILL EMPHASIZE THAT SILENT 10
POPS WILL REMAIN IN PLACE ESPECIALLY IN NORTHERN/WESTERN COUNTIES
TO AT LEAST ACKNOWLEDGE THAT A VERY LOW PROBABILITY OF SOME
ACTIVITY IS NOT COMPLETELY OUT OF THE QUESTION. IN THE MID-UPPER
LEVELS...THERE IS VERY LITTLE CHANGE WITH THE STRENGTH/ORIENTATION
OF THE EXPANSIVE RIDGE AXIS...AS IT REMAINS DRAPED FROM SOUTHWEST-
NORTHEAST ACROSS THE HEART OF THE CENTRAL PLAINS. A BIT LOWER AT
850MB...A 40+KT SOUTHERLY LOW LEVEL JET CRANKS UP THROUGH THE
NIGHT FROM WESTERN KS ACROSS CENTRAL NEB INTO EASTERN SD/WESTERN
MN...HELPING TO FOCUS THE VAST MAJORITY OF REGIONAL CONVECTION
NEAR THE EXIT REGION OF THIS FEATURE FROM NORTHEAST CO ACROSS
NORTHWEST NEB INTO SD/MN. AT THE SURFACE...THERE WILL ALSO BE
LITTLE OVERALL CHANGE FROM THE DAYTIME HOURS...WITH THE TROUGH
AXIS PERSISTING FROM NEAR THE KS/CO BORDER NORTH-NORTHEAST INTO
CENTRAL SD. WITH A CONTINUED MODEST PRESSURE GRADIENT AND LIMITED
MIXING UNDER THE LOW LEVEL JET...SURFACE BREEZES ACROSS THE CWA
WILL AGAIN AVERAGE 10-15 MPH FROM THE SOUTH-SOUTHEAST. ASSUMING
THAT POTENTIALLY ROGUE LATE AFTERNOON/EARLY EVENING STORMS DO NOT
AFFECT THE FAR WESTERN CWA...ITS PRETTY APPARENT FROM MOST MODEL
DEPICTIONS THAT OVERNIGHT CONVECTION SHOULD FOCUS AT LEAST 50-100
MILES NORTH THROUGH NORTHWEST OF THE CWA...AND GENERALLY LIFT
NORTH WITH TIME. THE ONLY FORESEEABLE CAVEAT HERE WOULD BE IF
NORTHERN NEB STORMS DEVELOP A COLD POOL AND START TO BUILD
SOUTHWARD INTO THE LOW LEVEL JET AXIS...POTENTIALLY REACHING THE
NORTHERN PARTS OF THE CWA. INTERESTINGLY...AT LEAST ONE
MODEL...THE 4KM WRF-NMM FROM PSU...DOES DEPICT THIS SCENARIO...BUT
GIVEN SUCH LIMITED SUPPORT WILL KEEP IT STORM-FREE FOR NOW. WILL
ALSO NOTE THAT THE 00Z GFS DEPICTION OF LATE NIGHT STORMS FLARING
UP NEAR HIGHWAY 81...LIKELY IN RESPONSE TO ANOTHER SUBTLE BATCH OF
MID LEVEL THETA-E ADVECTION...HAS BEEN DISREGARDED AS AN OUTLIER
AS WELL FOR THIS FORECAST. LOW TEMPERATURES WERE CHANGED
LITTLE...AND AGAIN REFLECT A SLIGHT UPWARD TREND FROM THE PAST FEW
NIGHTS...WITH MOST AREAS PROGGED TO BOTTOM OUT 72-75.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 431 AM CDT FRI JUL 12 2013
FOCUS FOR THIS TIMEFRAME WILL INVOLVE BOTH HIGH TEMPERATURES AND
PRECIPITATION CHANCES. MOST OF THE OPERATIONAL MODELS ARE COMING
INTO AGREEMENT ON THE UNUSUAL PATTERN EXPECTED IN THE SATURDAY TO
THURSDAY PERIOD. THEY ARE TAKING THE MID/UPPER LEVEL LOW PRESSURE
CURRENTLY SITTING OVER OHIO...AND RETROGRADING IT BACK TO THE
WEST. BY 12Z SAT THE GFS HAS IT OVER CENTRAL TENN...WHILE THE EC
PLACES IT A LITTLE NORTH OF THERE OVER KENTUCKY...AND THE NAM IS
BETWEEN THE TWO. BY 12Z SUNDAY THESE MODELS HAVE IT FROM CENTRAL
MISSOURI TO WESTERN ARKANSAS. THIS WESTWARD PUSH IS PROGGED TO
CONTINUE AND BY 12Z MONDAY IT IS FORECAST TO BE FROM NORTHERN
OKLAHOMA TO NORTHERN TEXAS. IT THEN APPEARS TO REMAIN OVER THE
TEXAS PANHANDLE OR IN NORTHEASTERN NEW MEXICO WHILE GRADUALLY
FILLING INTO THE WORKWEEK.
THIS IS NOT A VERY COMMON SCENARIO AND IF IT DOES COME TO FRUITION
WOULD MEAN COOLER TEMPERATURES STARTING SUNDAY. IN THE PAST 24
HRS...THE EXPECTED 850 MB TEMPS FOR SUNDAY OVER OUR AREA HAVE
DECREASED ABOUT 8-10 DEGREES C. GIVEN THE CONSISTENCY OF THE VARIOUS
OPERATIONAL MODELS WILL BUY INTO THIS SCENARIO AND LOWER HIGHS ON
SUNDAY BY SEVERAL DEGREES. SIMILAR TEMPERATURES CAN BE EXPECTED ON
MONDAY AND TUESDAY. WHILE COOLER THAN THOSE EXPECTED FOR TODAY AND
SATURDAY...WOULD NOT EXACTLY CALL IT COOL WEATHER AS HIGHS WILL
ACTUALLY BE AROUND NORMAL FOR THIS TIME OF YEAR FOR SUN-TUES. AFTER
THAT WE SHOULD SEE A GRADUAL WARMUP AS RIDGE RE-ESTABLISHES ITSELF
OVER THE REGION.
PRECIPITATION CONTINUES TO BE DIFFICULT TO FORECAST. LOOKS LIKE
THERE ARE AT LEAST SLIGHT CHANCES ON SAT AND SUNDAY NIGHTS OVER MUCH
OF THE CWA WITH A SURFACE BOUNDARY JUST TO OUR WEST...WEAK WAVES
ROTATING JUST TO OUR NORTH ALONG THE NORTHERN JET...AND THE
APPROACHING RETROGRADING LOW MENTIONED ABOVE. WILL CONTINUE TO
FORECAST DRY WEATHER FOR THE UPCOMING WORKWEEK BUT THAT MAY CHANGE
DEPENDING HOW FAR NORTH THAT RETROGRADING LOW TRACKS. AT
PRESENT...IT MAY AFFECT THE KANSAS PART OF OUR CWA BUT THE FURTHER
NORTH ITS TRACK...THE BETTER THE CHANCE FOR SOME RAIN IN THE NEB
PART OF OUR CWA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 123 PM CDT FRI JUL 12 2013
VFR CONDITIONS WILL PREVAIL THROUGH THE VALID TAF PERIOD AT KGRI.
AN UPPER LEVEL RIDGE WILL CONTINUE TO SIT OVER THE REGION AND
SHOULD PROVIDE MOSTLY CLEAR SKIES FOR THE TERMINAL. THE WIND
DIRECTION WILL REMAIN FAIRLY CONSTANT WITH A SOUTHERLY COMPONENT
THROUGH THIS PERIOD. WIND SPEEDS WILL REMAIN RATHER CONSISTENT AS
WELL. THE MAIN CONCERN OVER THE TAF PERIOD WILL BE THE LOW LEVEL
WIND SHEAR TONIGHT. THIS WILL BE MOSTLY A SPEED SHEAR TYPE OF
EVENT BUT SOME DIRECTIONAL SHEAR WILL BE NOTICED AS WELL ONCE THE
LOW LEVEL JET KICKS UP TONIGHT. A 30+KT DIFFERENCE IN WIND SPEED
FROM THE SURFACE TO 1500 WILL BE EXPERINCED TONIGHT. THE WIND
DIRECTION AT 1500 FT WILL BE OUT OF THE SOUTHWEST.
&&
.FIRE WEATHER...
ISSUED AT 431 AM CDT FRI JUL 12 2013
ALTHOUGH CRITICAL FIRE WEATHER CONDITIONS/DANGER ARE NOT
ANTICIPATED WITHIN THE CWA TODAY...NEAR-CRITICAL CONDITIONS ARE
FORECAST ESPECIALLY IN THE FAR SOUTHWEST IN THE PHILLIPS/ROOKS
COUNTY AREAS...AND THUS WILL INTRODUCE THIS MENTION INTO THE
HAZARDOUS WEATHER OUTLOOK. THIS AREA WILL FEATURE THE GREATEST
OVERLAP OF SUSTAINED WINDS/GUSTS 20/25 MPH...AND RELATIVE HUMIDITY
VALUES NEAR OR SLIGHTLY BELOW 25 PERCENT. CERTAINLY...AT LEAST A
LIMITED FIRE DANGER WILL EXIST ELSEWHERE ACROSS THE CWA GIVEN THE
STEADY BREEZES AND OVERALL DRY CONDITIONS OF LATE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR KSZ005-017>019.
&&
$$
UPDATE...GUERRERO
SHORT TERM...PFANNKUCH
LONG TERM...EWALD
AVIATION...GUERRERO
FIRE WEATHER...PFANNKUCH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1257 PM CDT FRI JUL 12 2013
.UPDATE...
ISSUED AT 1257 PM CDT FRI JUL 12 2013
ADJUSTED TEMPS DOWN A BIT IN THE NORTHWESTERN COUNTIES FOR THIS
AFTERNOON AS PERSISTANT CLOUDS AND SHOWERS HAVE MADE HIGHS WELL
INTO THE 80S DOUBTFUL. MADE SOME ADDITIONAL TWEAKS TO CLOUDS AND
POPS. THINK THAT THE CAP WILL START TO BREAK LATER THIS AFTERNOON
AND STORMS SHOULD START TO FIRE BY EVENING.
UPDATE ISSUED AT 940 AM CDT FRI JUL 12 2013
BUMPED UP POPS IN OUR NORTHEASTERN COUNTIES AS THERE HAS BEEN SOME
CONVECTIVE DEVELOPMENT ALONG THE NOSE OF THE 850MB WARM AIR
ADVECTION. THINK THAT THIS WILL TRANSITION NORTHEASTWARD BY THIS
AFTERNOON AND THEN THE FOCUS OF CONVECTION WILL BE THE COLD FRONT
MOVING INTO THE CENTRAL CWA. ALSO BUMPED UP HIGHS A TAD IN OUR
SOUTHERN COUNTIES AS MANY GUIDANCE VALUES HAVE THAT AREA GETTING
INTO THE 90S. THE RAP AND HRRR HAVE THE SOUTH CLIMBING INTO THE
100S THIS AFTERNOON BUT THAT SEEMS EXTREME GIVEN THE HIGH DEW
POINTS IN THE AREA.
UPDATE ISSUED AT 713 AM CDT FRI JUL 12 2013
AT 12Z... A QUASI STATIONARY FRONTAL SYSTEM STRETCHED FROM A LOW
PRESSURE CENTER IN WESTERN SD... THROUGH CENTRAL ND AND UP INTO A
LOW PRESSURE CENTER IN NRN MAN. WAVES OF SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS WERE PROPAGATING NORTHEASTWARD AHEAD OF
THIS FRONT... WITH ONE AREA PUSHING OUT OF THE NRN RED RIVER
VALLEY AS A SECOND AREA WAS MOVING THROUGH THE BISMARCK AREA AND
ARCING TOWARDS TEH DEVILS LAKE BASIN.
THESE SHOWERS LOOK TO PERSIST INTO THE THE LATE FORENOON... UNTIL
LOW LEVEL JET STRENGTH DIMINISHES. 06Z NAM40 GUIDANCE SUGGESTS
THAT BLAYER WARMING THROUGH THE FORENOON AND EARLY AFTERNOON
/AHEAD OF THE FRONT/ SHOULD PRODUCE MIXED LAYER CAPE VALUES OF
2000 J/KG OR GREATER BY 21Z... WHILE COOLING H7 TEMPS SHOULD ALLOW
FOR ONSET OF DEEP CONVECTION AS PER PREVIOUS DISCUSSION.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 355 AM CDT FRI JUL 12 2013
FORECAST CHALLENGE WILL BE THE EXTENT AND DURATION OF SHOWERS AND
THUNDERSTORMS THROUGH THIS MORNING... THEN TIMING OF REDEVELOPMENT
LATER TODAY AND TONIGHT.
FOR NOW... LOW LEVEL MOISTURE TRANSPORT APPEARS TO HAVE SURGED IN
THE LAST COUPLE OF HOURS LEADING TO INCREASED DEEP CONVECTION ACROSS
NCNTRL AND FAR NERN ND... AHEAD OF A WEAK SFC COLD FRONT. THIS
AREA SHOWS 1500-2000 J/KG OF CAPE AND PWATS IN EXCESS OF 1.5
INCHES AT 08Z ANALYSIS... WITH 40KM RAP AND NAM GUIDANCE LIFTING
THIS AREA THROUGH FAR NERN ND INTO SRN MAN THROHGH 15Z. EXPECT
SOME BREAK IN THE ACTIVITY THROUGH MIDDAY WITH SERN ND AND WCNTRL
MN LIKELY TO HEAT OUT QUICKLY AND REACH CONVECTIVE TEMPS BY
MIDAFTERNOON.
NAM DEPICTION SEEMS REASONABLE THROUGH TODAY AND INTO THE EARLY
PORTION OF THE WEEKEND... SHOWING THE SFC FRONT SLOWLY SAGGING
INTO THE SOUTHERN FA BY TONIGHT AND STALLING THERE THROUGH SUNDAY
MORNING. LATE THIS AFTERNOON INTO EARLY SATURDAY MORNING EXPECT
THE FOCUS FOR DEEP CONVECTION TO SHIFT ACROSS THE SOUTHERN FA...
WITH PERIODS OF STRONG TO SEVERE THUNDERSTORMS POSSIBLE ALONG WITH
BRIEF HEAVY RAINS. CONVECTIVE INHIBITION SHUD BREAK DOWN FAIRLY
QUICKLY THROUGH MID AFTERNOON AS COOLER H7 TEMPS MOVE OVHD... WITH
SOME THREAT FOR ISOLD TORNADIC SUPERCELLS TO DEVELOP IN THE LATE
AFTERNOON...THROUGH CENTRAL PORTIONS OF THE RRV.
OVERNIGHT TONIGHT THROUGH SATURDAY... FOCUS WILL SWITCH TO HEAVIER
RAIN PRODUCING CONVECTIVE CLUSTERS ACROSS THE SOUTHERN HALF OF THE
THE RRV.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
SATURDAY NIGHT THROUGH SUNDAY... SOME BREAK IN THE THUNDERSTORM
ACTIVITY IS EXPECTED TO DEVELOP FROM NORTHWEST TO SOUTHEAST ON
SATURDAY. DEEP MOIST AND UNSTABLE FLOW SHUD RETURN TO TEH AREA ON
SUNDAY.
MONDAY THROUGH THURSDAY... LONG WAVE UPPER LEVEL RIDGE REMAINS
PARKED OVER CO THIS PERIOD. LONG WAVE TROUGH OVER WESTERN CANADA
SWEEPS INTO EASTERN CANADA BY THE END OF THE PERIOD. FLOW ALOFT
BECOMES NORTHWEST ALOFT OVER CANADA AND THE FAR NORTHERN PLAINS. A
FRONTAL BOUNDARY MOVES INTO THE AREA TUE OR WED. WILL BLEND THE
ECMWF AND GFS.
NORTHWEST FLOW ALOFT BECOMES ESTABLISHED OVER CANADA AND THE
NORTHERN STATES THIS PERIOD. GFS AND ECMWF WERE VACILLATING OVER
SOUTHERN CANADA AND FAR NORTHERN ZONES TUE. SO WILL REMOVE
PRECIPITATION FROM TUE AND TRIM BACK TUE NIGHT PRECIP FARTHER NORTH.
WILL KEEP YESTERDAYS POPS FOR WED NIGHT.
HIGH TEMPS INCREASED COUPLE DEGREES IN THE NORTHWEST ZONES TUE FROM
YESTERDAYS RUN. BOTH HIGH AND LOW TEMPS DECREASED ABOUT A DEGREE OR
TWO FOR WED AND THU.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1257 PM CDT FRI JUL 12 2013
RELATIVELY NARROW BAND SHRA/TSRA JUST ALONG AND BEHIND FRONTAL
BOUNDARY DRIFTING SLOWLY EAST ACROSS CWFA. BOUNDARY FORECAST ALONG A
BDE...TVF...JMS LINE BY 00Z THEN TO NJI...DTL...FR LINE BY 06Z. AS
IS TYPICAL WITH CONVECTION TIMING IS DIFFICULT AS IS THE WINDS IN
AND AROUND THE SHRA. HAVE TIMES PCPN AND WIND VARIATIONS BASED ON
OBS AND FORECAST MOVEMENT OF FRONT.
WINDS WILL GUST AT FAR...TVF AND BJI INTO THE AFTERNOON AS GRADIENT
SLOW TO RELAX. MVFR VSBY PSBL WITH SHRA OTRW VFR CONDS FORECAST
OUTSIDE BAND OF CONVECTION.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...GUST
LONG TERM...HOPPES
AVIATION...EWENS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
321 PM EDT FRI JUL 12 2013
.SYNOPSIS...
UPPER LOW PRESSURE OVER WEST VIRGINIA WILL DRIFT WEST
TONIGHT...THEN THEN SLOWLY DRIFT WEST INTO KENTUCKY AND TENNESSEE
DURING THE WEEKEND. MEANWHILE...HIGH PRESSURE ALOFT WILL BUILD
WESTWARD FROM THE WESTERN ATLANTIC INTO THE MID- ATLANTIC REGION
BY EARLY NEXT WEEK. SHOWERS AND THUNDERSTORMS WILL CONTINUE
THROUGH THE WEEKEND...BUT SHOULD DIMINISH SOME NEXT WEEK AND
BECOME MORE ISOLATED AND TYPICAL OF SUMMER EARLY NEXT WEEK AS THE
UPPER RIDGE BUILDS OVER THE AREA.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 320 PM EDT FRIDAY...
FLASH FLOOD WATCH CONTINUES UNTIL 8 AM SATURDAY MORNING.
SCATTERED SHOWERS AND THUNDERSTORMS...SOME WITH HEAVY RAINS
WILL CONTINUE INTO TONIGHT. WITH PWAT STILL RELATIVELY HIGH...LOW
FFG(LESS THAN 1.0 INCH/HR IN SOME COUNTY) AND VERY WET
GROUND (RECENT RAINS)...THE POTENTIAL FOR FLASH FLOODING
CONTINUES THIS AFTERNOON INTO TONIGHT. HRRR AND RAP
FOCUS CONVECTION ON THE SOUTHERN BLUE RIDGE AND EASTWARD THIS
EVENING...THEN TAPER OFF OVERNIGHT INTO SATURDAY MORNING. GFS AND
NAM SEEM TO KEEP THE AXIS OF HEAVIER PRECIPITATION FURTHER EAST.
KEEP THE HIGHEST POPS THIS EVENING INTO TONIGHT...THEN DECREASE
POPS OVERNIGHT. EXPECTED SHOWERS TO LINGER INTO THE OVERNIGHT
HOURS WITH AREAS OF FOG. LOW TEMPERATURES TONIGHT WILL RANGE FROM
THE UPPER 50S IN THE MOUNTAINS TO THE UPPER 60S IN THE SOUTHEAST.
ON SATURDAY...THE CLOSED MID/UPR LOW WILL BE OVER KY AND IS
PROGGED TO DRIFT W REACHING THE MISS RIVER VALLEY BY 00Z SUNDAY.
PLENTY OF MOISTURE AND WEAK MID LEVEL VORTICITY CENTERS MOVE
ACROSS THE REGION DURING THE AFTERNOON AND EVENING CREATING
SCATTERED SHOWERS AND THUNDERSTORMS. ADDITIONAL FLASH FLOOD
WATCHES MAY BE ISSUED THIS WEEKEND.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH TUESDAY/...
AS OF 300 PM EDT FRIDAY...
BY SUNDAY MORNING...MOST OF THE MEDIUM RANGE MODELS ARE IN GOOD
AGREEMENT THAT THE UPPER LEVEL LOW WILL BE POSITIONED SOMEWHERE IN
THE MISSISSIPPI VALLEY WITH AN UPPER LEVEL HIGH BUILDING IN THE MID-
ATLANTIC REGION. WHILE THE DEEPEST MOISTURE WILL BE PULLED WEST OF
OUR FORECAST AREA...A WEAK SOUTHEAST LOW LEVEL FLOW AND WEAK WAVES
MOVING UNDER THE SOUTHERN PERIPHERY OF THE UPPER LEVEL HIGH WILL
BRING SCATTERED SHOWERS AND STORMS. PLACED THE HIGHEST POPS ALONG
THOSE FAVORED UPSLOPE EAST FACING SLOPES ALONG THE SOUTHERN BLUE
RIDGE.
DRIER AIR FINALLY ARRIVES SUNDAY NIGHT AND MONDAY AS PWATS FALL TO
UNDER 1.5 INCHES UNDER THE EXPANDING UPPER LEVEL RIDGE. WHILE
ISOLATED CONVECTION IS POSSIBLE IN THE MOUNTAINS...MOST AREAS WILL
BE DRY. WITH THE BUILDING RIDGE AND WARMING 850MB TEMPS...LEANED
TOWARD THE WARMER GFS GUIDANCE FOR FORECAST HIGHS.
CONTINUED VERY WARM TUESDAY...WITH SLIGHTLY INCREASED COVERAGE IN
SHOWERS AND STORMS IN THE MOUNTAINS AS PWATS INCREASE AND THE HINT
OF A WEAK UPPER LEVEL WAVE DRIFTS SOUTH UNDER THE UPPER RIDGE.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
AS OF 300 PM EDT FRIDAY...
THE LONG RANGE DETERMINISTIC AND ENSEMBLE MODELS ARE IN GOOD
AGREEMENT THAT AN LARGE UPPER RIDGE...AS STRONG AS 598DM...WILL OVER
OUR FORECAST AREA THROUGH THE LONG TERM PERIOD...WITH THE RIDGE
DAMPENING BY LATE IN THE WEEK AS A BROAD TROF FORMS IN EASTERN
CANADA.
TEMPERATURES WILL BE ABOVE NORMAL WITH GEFS ENSEMBLES SHOWING 850MB
TEMPS 1-2 STANDARD DEVIATIONS ABV AVERAGE AND 500MB HEIGHTS ALSO 1-2
SD ABOVE AVERAGE. INCREASED HIGHS A DEGREE OR TWO DURING THE LONG
TERM PERIOD. WHILE THE UPPER RIDGE WEAKENS LATE THE WEEK...A MORE
WESTERLY (DOWNSLOPING) COMPONENT TO THE WIND WILL KEEP TEMPS ABV
NORMAL.
EXPECT PRECIP TO BE DRIVEN BY DAYTIME HEATING...AND MAINLY CONFINED
TO THE MOUNTAINS. PWATS INCREASE FROM 1.5 TO GREATER THAN 2.0 INCHES
BY LATE IN THE WEEK...SO WHILE THE COVERAGE WILL BE WIDELY SCATTERED
SOME LOCALLY HEAVY DOWNPOURS WILL BE POSSIBLE.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
AS OF 130 PM EDT FRIDAY...
CLOSED UPPER LOW OVER THE AREA SCHEDULED TO RETROGRADE TO MIDWEST
OVER THE NEXT FEW DAYS. SCT-BKN MVFR CLOUDS WITH POCKETS OF IFR
IN CONVECTION AND AREAS OF FOG.
SCATTERED SHOWERS AND THUNDERSTORMS...SOME WITH HEAVY RAINS
EXPECTED THIS AFTERNOON INTO TONIGHT. BELIEVE THE TRENDS WILL BE
SIMILAR TO PREVIOUS DAYS IN A WEAKLY FORCED ENVIRONMENT. KLWB
HAS THE BEST CHANCE OF A THUNDERSTORM THIS AFTERNOON.
AS UPPER LOW BEGINS ITS WWD TREK...A SHORTWAVE WILL DRIFT OVER
THE AREA TONIGHT WITH FLOW BECOMING SELY. THIS SHOULD KEEP
SHOWERS IN THE AREA FOR THE OVERNIGHT. MODELS ALSO SHOW MOISTURE
SUCKING BACK WWD AS THE LOW MOVES...AND THIS SHOULD LEAD TO
IFR/LIFR CONDITIONS DEVELOPING OVERNIGHT.
.AVIATION EXTENDED...
DEEP EASTERLY FLOW CONTINUES INTO SATURDAY WITH WIDESPREAD SHOWERS
EXPECTED. SUNDAY THROUGH TUESDAY EXPECT A DAILY AFTERNOON AND
EVENING THREAT OF SHOWERS AND THUNDERSTORMS WITH EARLY MORNING IFR
BR/FG...BUT OVERALL IMPROVED CONDITIONS WITH MUCH MORE VFR THAN
CURRENT.
&&
.HYDROLOGY...
AS OF 120 PM EDT FRIDAY...
THE FLASH FLOOD WATCH CONTINUES THROUGH 8 AM EDT SATURDAY. GIVEN
THE EXPECTED WET PATTERN...IT MAY BE NECESSARY TO EXTEND INTO
SUNDAY MORNING...BUT HAVE DECIDED TO TAKE THIS ON A DAY-BY-DAY
BASIS. WE WILL EVENTUALLY GET OUT OF THIS PATTERN...BUT IT COULD
BE MONDAY BEFORE THAT HAPPENS IN EARNEST. IN THE MEANTIME...FFG
VALUES ARE EXTREMELY LOW AND ALTHOUGH INTENSE/ROBUST CONVECTION
SHOULD BE LESS WIDESPREAD TODAY...RAIN WILL BE OCCURRING OVER
AREAS THAT ARE EXCESSIVELY SATURATED AND SIMPLY CANNOT TAKE ANY
MORE RAINFALL AT ALL.
RIVER FLOOD WARNING IS CANCELLED FOR THE DAN RIVER NEAR DANVILLE.
FLOOD WARNINGS IN EFFECT FOR THE FOLLOWING RIVERS IN
VIRGINIA...DAN RIVER NEAR PACES...MINOR FLOODING IS FORECAST.
MINOR FLOODING IS ALSO OCCURING ALONG THE ROANOKE RIVER AT
RANDOLPH...DAN RIVER AT SOUTH BOSTON. REFER TO LATEST FLOOD
WARNINGS...RIVER FLOOD WARNINGS AND FLOOD STATEMENTS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR VAZ009-012>018-
022>024-032>035-043>047-058-059.
NC...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR NCZ001>006-
018>020.
WV...NONE.
&&
$$
SYNOPSIS...KK/RAB
NEAR TERM...KK
SHORT TERM...PH
LONG TERM...PH
AVIATION...KK/MBS/RAB
HYDROLOGY...KK/RAB
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
133 PM EDT FRI JUL 12 2013
.SYNOPSIS...
LOW PRESSURE WILL DRIFT INTO WEST VIRGINIA AND STALL...THEN DRIFT
SLOWLY BACK WEST INTO THE TENNESSEE VALLEY THROUGH EARLY NEXT
WEEK. MEANWHILE...HIGH PRESSURE ALOFT WILL BUILD WESTWARD FROM THE
WESTERN ATLANTIC INTO THE MID-ATLANTIC REGION BY EARLY NEXT WEEK.
SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH THE WEEKEND...BUT
SHOULD DIMINISH SOME NEXT WEEK AND BECOME MORE ISOLATED AND
TYPICAL OF SUMMER EARLY NEXT WEEK AS THE UPPER RIDGE BUILDS OVER
THE AREA.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1110 AM EDT FRIDAY...
FLASH FLOOD WATCH CONTINUES UNTIL 8 AM SATURDAY MORNING.
KFCX HAS BEEN REPAIRED AND IS BACK IN SERVICE.
SCATTERED SHOWERS AND THUNDERSTORMS...SOME WITH HEAVY RAINS
EXPECTED TO DEVELOP THIS AFTERNOON INTO TONIGHT. WITH PWAT STILL
RELATIVELY HIGH...LOW FFG AND VERY WET GROUND...THE POTENTIAL FOR
FLASH FLOODING CONTINUES. HRRR...AND RAP SEEM TO FOCUS ALONG
BLUE RIDGE AND EASTWARD THIS AFTERNOON INTO TONIGHT. UPPER LOW
PROGGED TO MOVE WESTWARD TODAY INTO WEEKEND. MADE SOME MINOR
ADJUSTMENTS IN POPS AND TEMPERATURES FOR THIS AFTERNOON.
MORE LATER....
AS OF 920 AM EDT FRIDAY...
FLASH FLOOD WATCH CONTINUES UNTIL 8 AM SATURDAY MORNING.
KFCX WILL BE DOWN THROUGH EARLY AFTERNOON FOR EMERGENCY REPAIRS.
PNS OUT WITH RAINFALL TOTALS.
THE 08AM/12Z RNK SOUNDING SHOWED PWATS ARE LOWER AT 1.09 INCHES
WITH NORTHERLY FLOW. INSTABILITY SHOULD BE LESS THIS AFTERNOON AS
MORE EASTERLY FLOW EVOLVES AROUND THE BUILDING ATLANTIC HIGH. BUT
WITH THE UPPER LOW...CONVECTION WITH POCKETS OF HEAVY RAIN WILL
DEVELOP THIS AFTERNOON INTO TONIGHT. THE THREAT FOR FLASH FLOODING
CONTINUES TODAY BECAUSE OF THE EXTREMELY LOW FFG VALUES...IN SOME
CASES LESS THAN 1.0 INCH/HR FOR FLASH FLOODING. ADJUSTED
TEMPERATURES AND DEWPOINTS FOR LATE MORNING INTO THIS AFTERNOON.
MODIFIED POPS INTO EARLY THIS AFTERNOON. WILL MAKE MORE
ADJUSTMENTS AS MORNING PROGRESSES.
AS OF 500 AM EDT FRIDAY...
FLASH FLOOD WATCH HAS BEEN EXTENDED UNTIL 8 AM SATURDAY MORNING.
EXCESSIVE RAINFALL IN PARTS OF THE FORECAST AREA THIS MORNING AS
UPPER LOW JUST TO OUR NORTHWEST COMBINED WITH VERY TROPICAL AIR
MASS ACROSS THE PIEDMONT CONTINUES. TRAINING AND BACKBUILDING
THUNDERSTORMS BROUGHT RECORD RAINFALL AMOUNTS TO DANVILLE
OVERNIGHT...WITH OVER FOUR INCHES OF RAIN AT THE DANVILLE AIRPORT
SINCE ABOUT 10 PM THURSDAY EVENING. RAINFALL OF THREE TO SIX
INCHES WAS COMMON ACROSS MUCH OF
CHARLOTTE...HALIFAX...PITTSYLVANIA...AND CAMPBELL COUNTIES.
SEVERAL WATER RESCUES REPORTED FROM DANVILLE CITY AND
PITTSYLVANIA COUNTY. MAIN STEM RIVER FLOODING ALSO ONGOING NOW AS
A RESULT ON THE ROANOKE AT RANDOLPH AND EXPECTED ON THE DAN LATER
TODAY AT SOUTH BOSTON.
THE DRYING EXPECTED A COUPLE OF DAYS AGO WILL BE POSTPONED UNTIL
NEXT WEEK UNFORTUNATELY. THE UPPER LOW TO OUR NORTHWEST WILL STALL
ACROSS WV AND THEN RETROGRADE SLOWLY TO THE WEST INTO KY/TN THROUGH
EARLY NEXT WEEK AS A MAMMOTH UPPER RIDGE EQUALLY RETROGRADE FROM
THE WESTERN ATLANTIC INTO THE MID-ATLANTIC REGION. THIS SHOULD
EVENTUALLY SHUT OFF THE EXCESSIVE RAINFALL AND RETURN US TO MORE
SUMMERLIKE CONDITIONS...BUT UNTIL THEN EXPECT MORE SHOWERS AND
THUNDERSTORMS.
THE GOOD NEWS FOR TODAY IS THAT PWATS ARE DOWN SLIGHTLY...MOSTLY
IN THE 1.5 TO 1.7 INCH RANGE AS OPPOSED TO 2.0+ INCHES. IN
ADDITION...INSTABILITY WILL BE LESS AS EASTERLY FLOW EVOLVES
AROUND THE BUILDING ATLANTIC HIGH. THERE SHOULD BE LESS INTENSE
CONVECTION AND MORE GENERAL STRATIFORM RAIN WITH EMBEDDED HEAVIER
CELLS. NONETHELESS...BECAUSE OF THE EXTREMELY LOW FFG VALUES...IN
SOME CASES LESS THAN 1.0 INCH/HR FOR FLASH FLOODING...HAVE OPTED
TO EXTEND THE FLASH FLOOD WATCH UNTIL 8 AM SATURDAY MORNING. HAVE
REMOVED ALLEGHANY COUNTY WHERE LESS RAINFALL HAS OCCURRED...BUT
ADDED SMYTH COUNTY AS SHRA/TSRA SPREAD IN THAT DIRECTION LATER
TODAY AND TONIGHT. THE MOST FAVORED AREAS AT THIS POINT FOR
ADDITIONAL HEAVY RAINFALL APPEAR TO BE SOUTH OF I-81...MOVING MORE
TOWARD OUR NW NC COUNTIES INTO THE WEEKEND. AS NOTED
ABOVE...HOWEVER...THE MAIN CONCERN IS ARE THE VERY LOW FFG VALUES
AND THE SIMPLE FACT THAT WE CANNOT TAKE HARDLY ANY ADDITIONAL
RAINFALL EAST OF THE ALLEGHANYS AT THIS POINT. THE WV COUNTIES
SHOULD BE JUST FINE AS THEY HAVE NOT HAD A FRACTION OF THE
RAINFALL MANY OF THE VA AND NC COUNTIES HAVE SEEN THE PAST TWO
WEEKS.
TEMPERATURES WILL REMAIN BELOW NORMAL THROUGH THE NEAR
TERM...THANKS TO CLOUDS...PCPN...AND EASTERLY FLOW.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
AN UPPER LEVEL RIDGE WILL BARREL TO THE WEST OVER THE WEEKEND. THIS
RIDGE WILL BE OFF THE MID ATLANTIC COAST ON SATURDAY THEN OVER THE
OHIO VALLEY BY SUNDAY NIGHT. THIS RIDGE WILL PUSH AN UPPER LEVEL LOW
WESTWARD ACROSS THE TENNESSEE VALLEY TO THE SOUTHERN PLAINS DURING
THE PERIOD. SHORT WAVES AND RAIN AXIS BETWEEN THESE TWO SYSTEMS WILL
BRING A GOOD CHANCE FOR RAIN TO THE REGION ON SATURDAY. WITH AN
EASTERLY UPSLOPE FLOW...HIGHER RAINFALL TOTALS WILL BE ALONG THE
BLUE RIDGE.
THIS RIDGE WILL BRING VERY WARM AND HUMID CONDITIONS TO THE REGION.
85H TEMPERATURES WILL WARM TO +22C BY MONDAY. TEMPERATURES ACROSS
THE MOUNTAIN WILL RANGE FROM THE LOWER TO MID 80S THIS WEEKEND. EAST
OF THE BLUE RIDGE WILL SEE TEMPERATURES APPROACHING 90F.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 300 PM EDT THURSDAY...
MODEL GUIDANCE HAS COME TO BETTER AGREEMENT ON THE EVOLUTION OF THE
UPPER-LEVEL PATTERN NEXT WEEK WHICH WILL FEATURE A BUILDING UPPER
LEVEL RIDGE OVER THE MID ATLANTIC. THE UPPER LOW WHICH DEVELOPS AND
BREAKS AWAY FROM THE UPPER TROUGH OVER NEW ENGLAND THIS WEEKEND IS
FORECAST TO RETROGRADE AND PUSH WEST-SOUTHWEST REACHING THE
SOUTHERN PLAINS BY THE MIDDLE OF NEXT WEEK...DAY 7.
THIS SUGGESTS LIFT FOR SHOWERS AND STORMS NEXT WEEK WILL BE LIMITED
TO DAYTIME HEATING...THE UPPER LOW MOVING TOO FAR WEST TO BE AN
INFLUENCE. IF THE RIDGE OF HIGH PRESSURE IS AS ROBUST AS FORECAST
597DM...THIS MAY CAUSE ENOUGH WARMING ALOFT TO POTENTIALLY LIMIT
DEEP CONVECTION TO LESS THAN 20 PERCENT COVERAGE EXCEPT FOR MAYBE
THE MOUNTAINS.
MODEL TEMPS HAVE TRENDED WARMER...BUT STILL NOTHING EXTREME. 85H
TEMPS ARE FCST TO BUILD CLOSE TO +20 DEG C BY MID WEEK WHICH SUGGEST
HIGH TEMPS WELL INTO THE 80S...POSSIBLY 90 URBAN AREAS. LOWS SHOULD
ALSO CREEP UPWARD A LITTLE WITH TMINS IN THE 60S TO AROUND 70.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 130 PM EDT FRIDAY...
CLOSED UPPER LOW OVER THE AREA SCHEDULED TO RETROGRADE TO MIDWEST
OVER THE NEXT FEW DAYS. SCT-BKN MVFR CLOUDS WITH POCKETS OF IFR
IN CONVECTION AND AREAS OF FOG.
SCATTERED SHOWERS AND THUNDERSTORMS...SOME WITH HEAVY RAINS
EXPECTED THIS AFTERNOON INTO TONIGHT. BELIEVE THE TRENDS WILL BE
SIMILAR TO PREVIOUS DAYS IN A WEAKLY FORCED ENVIRONMENT. KLWB
HAS THE BEST CHANCE OF A THUNDERSTORM THIS AFTERNOON.
AS UPPER LOW BEGINS ITS WWD TREK...A SHORTWAVE WILL DRIFT OVER
THE AREA TONIGHT WITH FLOW BECOMING SELY. THIS SHOULD KEEP
SHOWERS IN THE AREA FOR THE OVERNIGHT. MODELS ALSO SHOW MOISTURE
SUCKING BACK WWD AS THE LOW MOVES...AND THIS SHOULD LEAD TO
IFR/LIFR CONDITIONS DEVELOPING OVERNIGHT.
.AVIATION EXTENDED...
DEEP EASTERLY FLOW CONTINUES INTO SATURDAY WITH WIDESPREAD SHOWERS
EXPECTED. SUNDAY THROUGH TUESDAY EXPECT A DAILY AFTERNOON AND
EVENING THREAT OF SHOWERS AND THUNDERSTORMS WITH EARLY MORNING IFR
BR/FG...BUT OVERALL IMPROVED CONDITIONS WITH MUCH MORE VFR THAN
CURRENT.
&&
.HYDROLOGY...
AS OF 120 PM EDT FRIDAY...
THE FLASH FLOOD WATCH CONTINUES THROUGH 8 AM EDT SATURDAY. GIVEN
THE EXPECTED WET PATTERN...IT MAY BE NECESSARY TO EXTEND INTO
SUNDAY MORNING...BUT HAVE DECIDED TO TAKE THIS ON A DAY-BY-DAY
BASIS. WE WILL EVENTUALLY GET OUT OF THIS PATTERN...BUT IT COULD
BE MONDAY BEFORE THAT HAPPENS IN EARNEST. IN THE MEANTIME...FFG
VALUES ARE EXTREMELY LOW AND ALTHOUGH INTENSE/ROBUST CONVECTION
SHOULD BE LESS WIDESPREAD TODAY...RAIN WILL BE OCCURRING OVER
AREAS THAT ARE EXCESSIVELY SATURATED AND SIMPLY CANNOT TAKE ANY
MORE RAINFALL AT ALL.
RIVER FLOOD WARNING IS CANCELLED FOR THE DAN RIVER NEAR DANVILLE.
FLOOD WARNINGS IN EFFECT FOR THE FOLLOWING RIVERS IN
VIRGINIA...DAN RIVER NEAR PACES...MINOR FLOODING IS FORECAST.
MINOR FLOODING IS ALSO OCCURING ALONG THE ROANOKE RIVER AT
RANDOLPH...DAN RIVER AT SOUTH BOSTON. REFER TO LATEST FLOOD
WARNINGS...RIVER FLOOD WARNINGS AND FLOOD STATEMENTS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR VAZ009-012>018-
022>024-032>035-043>047-058-059.
NC...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR NCZ001>006-
018>020.
WV...NONE.
&&
$$
SYNOPSIS...RAB/KK
NEAR TERM...KK/RAB
SHORT TERM...RCS
LONG TERM...PM
AVIATION...MBS/RAB/KK
HYDROLOGY...KK/RAB