FXUS62 KJAX 081945
AFDJAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
245 PM EST TUE DEC 8 2009
...BREEZY WITH NEAR RECORD HIGH TEMPERATURES WEDNESDAY...
.SHORT TERM...TONIGHT THROUGH FRIDAY...
REST OF THIS AFTERNOON...WARM FRONTAL BOUNDARY HAS LIFTED NORTH OF
THE BORDER JUST INTO SERN GA AND MAJORITY OF SCTD TO NUMEROUS
SHOWERS WILL PUSH ALONG BOUNDARY IN THAT AREA. AN ISOLD TSTM WILL BE
POSSIBLE THROUGH SUNSET ALONG THE WARM FRONT AND POSSIBLE AS WELL
ACRS NERN FL IN WARM SECTOR.
TONIGHT...WARM FRONT SETTLES NORTH OF THE REGION AND STRONG WARM AIR
ADVECTION WITH FLOW OUT OF THE SOUTHWEST WILL MAKE FOR A MILD NIGHT
WITH MIN TEMPS IN THE MID/UPPER 60S ACRS MUCH OF THE REGION. SHOWER
ACTIVITY THIS EVENING SHOULD WIND DOWN BY MIDNIGHT.
WEDNESDAY...TRAILING FRONTAL BOUNDARY SETTLES SOUTH INTO THE
FORECAST AREA WITH SCATTERED TO NUMEROUS SHOWERS AND EMBEDDED
THUNDERSTORMS. STRONG LOW LEVEL JET AHEAD OF THE FRONT WILL PROMOTE
BREEZY CONDITIONS OF 15-20 MPH WITH GUSTS UP TO 30-35 MPH AND A LAKE
WIND ADVISORY MAY BE NEEDED. WARM SOUTHWEST FLOW WILL PUSH MAX TEMPS
INTO THE UPPER 70S AND LOWER 80S WHICH WILL BE NEAR RECORD HIGH
TEMPS FOR THE DATE AND ARE LISTED BELOW.
JAX 84/2004...GNV 87/1951...AMG 81/1978...SSI 83/1978
THE SAME LOW LEVEL JET RESPONSIBLE FOR THE WARMTH WILL ALSO PROVIDE
THE POTENTIAL FOR STRONG GUSTY WINDS IN ISOLD TSTM ACTIVITY AS WELL
AND WITH DAYTIME HEATING SOME STRONG TO ISOLD SVR TSTMS COULD BE
POSSIBLE.
WED NIGHT...FRONT STALLS OVER NORTHEAST FLORIDA AND NEXT IMPULSE
DRIVES NORTHEAST OUT OF THE GOMEX AND SHOULD RE-ENERGIZE WEAKENING
BOUNDARY AND WILL CONTINUE SCATTERED SHOWERS AND ISOLD TSTMS ACRS
NERN FL WITH SOME ISOLD SHOWER ACTIVITY IN OVERRUNNING ACRS SERN GA
AS WELL. MIN TEMP FCST BECOMES RATHER CHALLENGING DEPENDING ON
ADVANCEMENT OF FRONT AND HAVE GONE ABOUT 3-5 DEGS WARMER THAN THE
CURRENT GFS MOS GUIDANCE WITH 50S ACRS THE REGION EXCEPT FOR 40S
ACRS SERN GA.
THURSDAY...LATEST IMPULSE CONTINUES ISOLD/SCTD SHOWER ACTIVITY IN
THE MORNING HOURS BEFORE SLOW IMPROVEMENT AND LINGERING RAINFALL
ENDING DURING THE AFTERNOON HOURS. COLD AIR CONTINUING TO SEEP IN
AND WITH CLOUDY SKIES EXPECT MAX TEMPS ONLY IN THE 50S.
THURSDAY NIGHT...WITH FRONT JUST SOUTH OF THE REGION AND PARTLY
CLOUDY SKIES EXPECT A MAINLY RAIN FREE PERIOD WITH MIN TEMPS FALLING
INTO THE 30S ACRS SERN GA AND I-10 CORRIDOR AND 40S FURTHER SOUTH.
FRIDAY...NEXT IMPULSE OF ENERGY IN WSW ZONAL FLOW QUICKLY INCREASES
CLOUDS WITH SHOWERS POSSIBLE AGAIN BY THE AFTERNOON HOURS. FORECAST
CONFIDENCE STARTS TO FALL APART THIS FAR OUT IN DAY 3 WITH THIS FAST
MOVING PATTERN. FRONT WILL RETURN SLOWLY BACK TO THE NORTH BUT STILL
EXPECT MAX TEMPS TO HOLD ONLY IN THE 50S TO LOWER 60S.
FRIDAY NIGHT...STRONG LIFT AND SUPPORT ALOFT FROM FAVORABLE RIGHT
ENTRANCE REGION TO JET STREAM WILL ENHANCE PCPN AND LOCALLY HEAVY
RAINFALL AND EMBEDDED TSTM ACTIVITY WILL BE POSSIBLE AS SFC LOW
DEVELOPMENT TAKES PLACE DIRECTLY OVER THE REGION.
.LONG TERM...SATURDAY THROUGH TUESDAY...
SATURDAY...SFC LOW DEVELOPMENT OVER THE REGION WILL SLIDE TO THE
NORTHEAST AND MOVE OFFSHORE BUT RAINFALL CHANCES WILL CONTINUE ALONG
TRAILING BOUNDARY BACK ACRS THE FORECAST AREA AND HAVE KEPT RAIN
CHANCES IN THE 30-50% RANGE.
SUNDAY...WITH DEPARTING LOW PRESSURE AND LACK OF FOCUS FOR
RAINFALL...PCPN CHANCES FALL TO AROUND 15-20% AND MAY SEE ONLY ISOLD
SHOWERS IN ANY LINGERING OVERRUNNING NORTH OF FRONTAL BOUNDARY.
SKIES TO BECOME PARTLY CLOUDY WITH MAX TEMPS IN THE 60S ACRS SERN GA
AND LOWER 70S ACRS NERN FL.
MONDAY AND TUESDAY...NEXT IMPULSE OF ENERGY FROM UPSTREAM PUSHES
INTO SERN U.S. AND PRODUCES ANOTHER WARM FRONTAL RAIN EVENT ON
MONDAY AND TRAILING COLD FRONTAL RAIN EVENT ON TUESDAY. TIMING AND
STRENGTH OF EVENT STILL UNCERTAIN...BUT TRAILING COLD FRONT MAY BE
STRONG ENOUGH TO PRODUCE ISOLD SEVERE WEATHER.
&&
.AVIATION...WARM FRONT WILL LIFT NORTH OF THE TERMINALS LATER THIS
EVENING ALLOWING FOR A MODEST SOUTHERLY COMPONENT TO DEVELOP. THIS
SHOULD ALLOW FOR AN INCREASED MIXING PROFILE WITH LIMITED POTENTIAL
FOR LIFR CONDITIONS. BUT AS WE HAVE SEEN THE PAST TWO
NIGHTS...LITTLE IS STRAIGHTFORWARD IN THIS WEATHER PATTERN. WILL
THEREFORE HEDGE SLIGHTLY TOWARD THE PESSIMISTIC SIDE BUT NOT NEAR AS
LOW AS THE GUIDANCE INDICATE...KEEPING MOSTLY MVFR TO OCCASIONAL IFR
FORECAST. LOOKS AS THOUGH MAIN FRONTAL CONCERNS WILL BE DURING THE
LATTER HALF OF THIS FORECAST PERIOD AND DECREASING MOISTURE AND LIFT
SHOULD PRECLUDE ANY TEMPOS AT THIS TIME AND WE SHOULD GET BY WITH
JUST VCTS.
&&
.MARINE...WILL BE DIFFICULT TIMING THE WARM FRONT THIS EVENING AND
HAVE LEANED TOWARD A SLOWER SOLUTION FOR THE SHORT TERM GRIDS.
ONCE WINDS DO COME AROUND TO SOUTH...THEY WILL SIGNIFICANTLY
INCREASE BUT GFS AND NAM12 DISAGREE AS TO HOW MUCH. GFS IS MUCH
STRONGER WITH NEAR 25 KNOTS SUSTAINED AT TIMES OVER THE OFFSHORE
PORTION. USUALLY DO NOT SEE WINDS QUITE THAT STRONG IN SOUTHERLY
REGIME AND WILL BLEND IN THE NAM12 FOR THIS FORECAST CYCLE. STILL
WILL BE SUFFICIENT WINDS TO KEEP SCA GOING OVER THE OFFSHORE
PORTION THROUGH WED EVENING. A COUPLE OF SECONDARY SURGES FROM THE
NORTHEAST WILL LIKELY REQUIRE ADDITIONAL FLAGS TOWARD THE END OF THE
WORK WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 58 78 43 54 / 30 40 20 10
SSI 65 78 53 57 / 30 30 20 20
JAX 66 82 51 57 / 20 40 30 20
SGJ 68 83 56 61 / 20 30 40 30
GNV 63 80 54 58 / 10 60 40 30
OCF 65 82 57 62 / 10 50 50 40
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...SMALL CRAFT ADVISORY FROM 11 PM THIS EVENING TO 7 PM EST
WEDNESDAY FOR ALTAMAHA SOUND GA TO FERNANDINA BEACH FL 20
NM TO 60 NM OFFSHORE-FERNANDINA BEACH TO ST AUGUSTINE FL 20
NM TO 60 NM OFFSHORE-ST AUGUSTINE TO FLAGLER BEACH FL 20 NM
TO 60 NM OFFSHORE.
&&
$$
HESS/DEESE/WALKER
