Severe Thunderstorm Warning 98, NWS Tallahassee, FL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
356 PM EDT WED JUN 3 2015

.NEAR TERM [THROUGH TONIGHT]...

THE UPPER LOW CONTINUES TO SPIN OVER THE SOUTHERN APPALACHIANS NEAR
THE NC/GA BORDER. WATER VAPOR IMAGERY INDICATES THAT QUITE A BIT OF
MID/UPPER LEVEL DRY AIR HAS ROTATED INTO THE AREA ON THE SOUTH SIDE
OF THIS LOW. THE POSITION OF THE UPPER TROUGH PUTS US IN A DNVA
SCENARIO TODAY, SO THERE WILL BE LESS QG FORCING TO AID ASCENT.
THEREFORE THE SEA BREEZE SHOULD BE THE PRIMARY TRIGGER ACROSS MOST
OF THE FORECAST AREA. WE ARE IN A FAVORABLE LOW-MID LEVEL FLOW
REGIME. THERE IS, HOWEVER, A STALLED FRONTAL BOUNDARY OVER SOUTHEAST
AL THAT COULD FOCUS CONVECTION IN THAT AREA. POPS WERE ONCE AGAIN
WERE WEIGHTED TOWARD THE ECAM NUMBERS. WE REMAIN IN A MARGINAL SPC
RISK FOR SEVERE STORMS ACROSS MAINLY OUR GA AND INLAND FL BIG BEND
ZONES. WE FEEL THE MOST LIKELY AREA FOR SEVERE TODAY WILL BE ACROSS
GA, WITH LOCALLY DAMAGING GUSTY WINDS THE MAIN THREAT. HOWEVER, HAIL
WILL BECOME MORE LIKELY AS YOU MOVE NORTH TOWARD THE COLD POOL. DEEP
LAYER SHEAR IS UP AROUND 25-30 KT WHICH COULD FAVOR SOME STORM
ORGANIZATION IN THE OUTLOOK AREA.

.SHORT TERM [THURSDAY THROUGH FRIDAY NIGHT]...

THE AFOREMENTIONED MID-UPPER LEVEL CUTOFF LOW WILL TRANSLATE
SLOWLY NORTHEAST OFF THE MID ATLANTIC COAST FRIDAY, AS IT MERGES
WITH THE MID LATITUDE WESTERLIES. THE MID TO UPPER LEVEL FLOW WILL
GO FROM LIGHT AND VARIABLE THURSDAY TO NORTHERLY BY FRIDAY, AS
HEIGHTS RISE OVER TX. AT THE SURFACE, THE FRONTAL ZONE CURRENTLY
NORTH AND WEST OF OUR FORECAST AREA WILL BECOME NEARLY STATIONARY,
AND ORIENTED ALONG THE FL-GA BORDER AS IT GRADUALLY DISSIPATES.
ALTHOUGH THE AIR ABOVE 500 MB HAS DRIED CONSIDERABLY ALREADY,
THERE REMAINS AMPLE MOISTURE BELOW TO SUPPORT DEEP MOIST
CONVECTION. THE MOS CONSENSUS, ESPECIALLY THE GFS AND NAM MOS,
FORECAST LOW POPS (20 PERCENT) FOR THURSDAY; BUT OUR ENSEMBLE OF
CONVECTION ALLOWING MODELS (ECAM) HAS A POP IN THE FL PANHANDLE
OF 40-60 PERCENT. GIVEN THE FAVORABLE LOW LAYER MOISTURE, CAPE,
AND SEA BREEZE/FRONTAL ZONE CONVERGENCE, WE WEIGHTED OUR FORECAST
MORE TOWARD THE ECAM SOLUTION.

ON FRIDAY THE POP WILL BE A LITTLE LOWER AND MORE EVENLY DISTRIBUTED
AS THE FRONTAL ZONE DISSIPATES AND DRIER AIR BECOMES MORE
ENTRENCHED. WE'RE FORECASTING A POP OF 20-30 PERCENT, WITH THE
HIGHEST POP ACROSS NORTH FL WHERE THERE WILL BE MORE DEEP LAYER
MOISTURE. THE MEAN, DEEP, OFFSHORE FLOW WILL TEND TO RETARD THE
PANHANDLE AND BIG BEND SEA BREEZE FRONT DEVELOPMENT AND INLAND
PROPAGATION, SO THUNDERSTORMS MAY NOT INITIATE UNTIL LATER IN THE
AFTERNOON. TEMPERATURES WILL BE NEAR NORMAL, WITH LOWS IN THE
UPPER 60S AND HIGHS IN THE LOWER 90S. WEAK WINDS ALOFT WILL BE
TYPICALLY WEAK FOR THIS TIME OF YEAR AND THIS PART OF THE COUNTRY,
SO SIGNIFICANT THUNDERSTORMS ORGANIZATION IS UNLIKELY. HOWEVER, A
PULSE SEVERE STORM OR TWO WILL BE POSSIBLE.

.LONG TERM [SATURDAY THROUGH WEDNESDAY]...

A WEAK MID-UPPER LEVEL TROUGH ALONG THE SOUTHEAST U.S. COAST ON
SATURDAY WILL GRADUALLY FILL AS HIGHER HEIGHTS IN TX ATTEMPTS TO
JOIN THE WEST ATLANTIC RIDGE. OUR FORECAST AREA WILL BE ON THE
WESTERN PERIPHERY OF THE WEST ATLANTIC RIDGE (I.E. BERMUDA RIDGE).
THIS LARGE SCALE PATTERN, COUPLED WITH NEAR-AVERAGE THERMODYNAMICS,
SUGGEST NEAR-CLIMO POPS (AROUND 30 PERCENT) EACH AFTERNOON &
EVENING. TEMPERATURES WILL ALSO BE NEAR NORMAL, WITH LOWS IN THE
LOWER 70S AND HIGHS IN THE LOWER 90S.

&&

.AVIATION...

[THROUGH 18Z THURSDAY] SCATTERED SHOWERS AND THUNDERSTORMS WILL
CONTINUE TO DEVELOP THROUGH THE AFTERNOON. IT IS REASONABLE TO ASSUME
THAT MOST OF THE TERMINALS WILL HAVE TS IN THE VICINITY WITH DECENT
CHANCES THAT ONE WILL DIRECTLY IMPACT THE AIRPORTS. MVFR CONDITIONS
WILL BE POSSIBLE AROUND SUNRISE THURSDAY, AND IFR CANNOT BE RULED
OUT. HOWEVER, THAT IS MOST LIKELY AT VLD.

&&

.MARINE...

THE PRESSURE GRADIENT WILL REMAIN VERY WEAK ACROSS OUR MARINE AREA,
WHICH IS TYPICAL FOR THIS TIME OF YEAR. THE PRIMARY DRIVER OF THE
WINDS WILL BE LAND AND SEA BREEZE CIRCULATION.

&&

.FIRE WEATHER...

UNUSUALLY LOW DISPERSIONS ARE POSSIBLE IN THE NORTHERN HALF OF
THE FORECAST AREA THURSDAY. NO HAZARDOUS FIRE WEATHER CONDITIONS
ARE EXPECTED OVER THE NEXT SEVERAL DAYS.

&&

.HYDROLOGY...

THE ONLY RIVER AT LOCAL ACTION STAGE WAS AT BRUCE, ON THE
CHOCTAWHATCHEE RIVER, BUT IT'S EXPECTED TO FALL BELOW ACTION STAGE
THIS WEEKEND. OTHERWISE, WE DO NOT EXPECT THE DAILY RAINFALL TO BE
ORGANIZED ENOUGH TO CAUSE SIGNIFICANT RIVER RISES OR FLASH FLOODING.

&&

.PRELIMINARY POINT TEMPS/POPS...

TALLAHASSEE   69  92  69  91  69 /  20  30  20  20  20
PANAMA CITY   72  85  72  86  73 /  10  40  10  20  10
DOTHAN        69  90  69  91  70 /  40  20  20  10  10
ALBANY        68  89  68  90  69 /  40  10  10  20  10
VALDOSTA      67  90  68  91  67 /  50  20  20  20  20
CROSS CITY    67  92  69  91  68 /  20  20  30  30  20
APALACHICOLA  71  87  72  87  72 /  10  20  10  20  10

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AL...NONE.
GM...NONE.
&&

NEAR TERM...WOOL
SHORT TERM...FOURNIER
LONG TERM...FOURNIER
AVIATION...WOOL
MARINE...FOURNIER
FIRE WEATHER...DVD
HYDROLOGY...FOURNIER