Issued by NWS Jacksonville, FL
000 FXUS62 KJAX 220826 AFDJAX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE JACKSONVILLE FL 325 AM EST SUN NOV 22 2009 ...FEW STRONG OR POSSIBLY SEVERE STORMS ACROSS NE FL THIS AFTERNOON... .SHORT TERM (SUN-TUE)...STACKED LOW ALONG THE LA COAST TRACKS ALONG THE GULF COAST TODAY AND IS FORECAST TO WEAKEN TO AN OPEN WAVE. WARM FRONT ACROSS CENTRAL FL PUSHES NORTH INTO NE FL NEAR THE I-10 CORRIDOR BY THIS AFTERNOON AND MAKING IT INTO EXTREME SE GA THIS EVE BEFORE STALLING OUT. WEAK OCCLUDED LOW TRACKS ACROSS THE AREA TONIGHT BRINGING DRY SLOT INTO THE AREA MONDAY. HAVE GONE LIKELY POPS ALL AREAS TODAY AND FOLLOWED HPC QPF. PCP ENDS FROM W-E TONIGHT AS DRY SLOT APPROACHES THE AREA. QUITE A TEMP DIFF NORTH AND SOUTH OF THE WARM FRONT AND WENT WITH A BLEND OF MAV/MET. TEMPS IN FAR NW CORNER OF FCST AREA REMAINING IN THE 50S WHILE AREAS SOUTH OF I-10 GET WELL INTO THE 70S AND EVEN NEAR 80. WITH FRONT WASHING OUT IN THE AREA FOG POTENTIAL HIGH NEXT COUPLE OF NIGHTS AND HAVE INCLUDED PATCHY DENSE FOG EVERYWHERE IN THE GRIDS. SVR WX POTENTIAL TODAY...MAIN CONCERN WILL BE FOR THE POSSIBILITY OF ISOLATED SEVERE STORMS OR EVEN AN ISOLATED TORNADO AS THE WARM FRONT MOVES INTO THE AREA THIS AFTERNOON. THAT WOULD DEPEND ON HOW MUCH LOW LEVEL DESTABILIZATION CAN OCCUR. WITH THE STRONG WEDGE IN THE AREA AND CLOUD COVER APPEARS INSTABILITY WILL BE LIMITED. THE NAM IS INDICATING EHI INDICES OF 1-1.5 NEAR THE WARM FRONT THIS AFTERNOON WHICH MAY BE ENOUGH FOR AN ISOLATED SEVERE STORM OR TORNADO. WILL CONTINUE TO MENTION POSSIBILITY OF AN ISOLD SEVERE STORM IN THE HWO FOR TODAY. .LONG TERM (WED-SAT)...AN INVERTED SFC TROUGH IS EXPECTED TO AMPLIFY OFFSHORE OF THE FL COAST WED AS A STRONG UPPER LEVEL TROUGH AND WEAK SFC FRONT APPROACH FROM THE WEST. THIS WILL INCREASE LOW LEVEL ISENTROPIC LIFT OVER OUR CWA. HAVE CONTINUED WITH PREVIOUS FORECAST OF LOW POPS WED AND WED NIGHT. POPS DECREASE THU AS COLD AND DRY AIR FILTER OVER THE AREA FROM THE NW. LARGE TROUGH AMPLIFIES ALONG THE EASTERN U.S. TOWARDS THE END OF THE WEEK. TEMPS WILL AVERAGE SLIGHTLY ABOVE NORMAL THROUGH MID WEEK THEN A TREND TO BELOW NORMAL TEMPS BY THE END OF THE WEEK AND NEXT WEEKEND. && .AVIATION...DETERIORATING CONDITIONS EXPECTED DURING THE DAY AT TAF SITES AS WARM FRONT SLOWLY LIFTS NORTHWARD ACRS NCNTRL FL...STALLING OVER NRN FL THIS EVNG. WIDESPREAD LOW CIGS EXPECTED TO DEVELOP N OF WRMFNT...WITH SOME IMPROVEMENT S OF FRONT. TAFS SHOW LOWERING CIGS EVENTUALLY INTO IFR RANGE...WITH SOME IMPROVEMENT PSBL DURING AFTN FOR KGNV IF IT ENDS UP S OF WARM FRONT. SOME UNCERTAINTY EXISTS WITH REGARD TO HOW LOW CIGS GET DURING DAY AND HOW QUICKLY THEY LOWER. MOS/LAMP GUIDANCE CONSISTENT IN SHOWING LOWERING CIGS...BUT DIFFER A LITTLE ON CIG VALUES BY AFTN...BUT INCREASE LEVEL OF CERTAINTY OF LOW CIG DVLPMENT. ATTM DID NOT INCLUDE TSRA IN TAFS GIVEN LACK OF INSTABILITY. MODEL GUIDANCE SUGGEST WEAK INSTABILITY MAY LEAD TO ISOLD TS IN THE AFTN. LATER TAF ISSUANCES MAY NEED TO INCLUDE TSRA...ESP KGNV. MODEL GUIDANCE IN AGREEMENT ON CONDITIONS LOWERING FURTHER TO LIFR CONDITIONS BY LATE TNGT. ATTM...HINTED LOWERING CONDITIONS TOWARD 06Z IN PRIOR TAFS. WITH FRONT STALLING OVER THE AREA...WEAK WINDS... AND MOIST GROUND FROM FCST RAINFALL...COULD SEE WIDESPREAD LOW CIGS/VSBYS THROUGH MUCH OF TNGT INTO EARLY TMRW MRNG. CONFIDENCE ON THIS SCENARIO A LITTLE ABOVE NORMAL GIVEN AGREEMENT AMONG DIFFERENT MODEL GUIDANCE SOURCES. && .MARINE...WILL CONTINUE WITH EXERCISE CAUTION 20-60NM OFFSHORE COMPONENT WITH CONTINUED 4-6FT EASTERLY SWELL TODAY. WARM FRONT WILL MOVE NORTHWARD ACROSS THE WATERS...STALLING OVER FAR NORTHERN FL AND COASTAL WATERS TNGT AND MON BEFORE SHIFTING S OF THE AREA TUE. EXPECT SLIGHT DECREASE IN WINDS AND SEAS MON-TUE...BEFORE INCREASING LATER IN THE WEEK AS A COLD FRONT MOVES ACROSS THE AREA. && .PRELIMINARY POINT TEMPS/POPS... AMG 59 48 64 47 / 90 30 10 10 SSI 65 57 68 52 / 70 50 10 10 JAX 69 57 75 51 / 70 50 10 10 SGJ 75 64 76 57 / 50 50 10 10 GNV 77 59 78 53 / 60 50 10 10 OCF 79 61 79 55 / 60 50 20 10 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AM...NONE. && $$ PP/PW
