FXUS62 KTBW 260826
AFDTBW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL
326 AM EST THU NOV 26 2009
.SHORT TERM (TODAY - SATURDAY)...WATER VAPOR IMAGERY ILLUSTRATES THE
RAPIDLY CHANGING WEATHER PATTERN ACROSS THE REGION WITH A
PROGRESSIVE MAINSTREAM FLOW ACROSS THE CONUS. EL NINO SPLIT-FLOW
PATTERN IS PREVALENT ACROSS THE CONTINENTAL U.S. WITH A HIGH
AMPLITUDE RIDGE FORCING PACIFIC ENERGY INTO WESTERN CANADA AND OVER
WA/OR WHILE A CUTOFF LOW MEANDERS OVER SOUTHERN CALIFORNIA ABOVE THE
SPLIT SOUTHERN STREAM JET FORCING ANOTHER DISTURBANCE ACROSS
MEXICO. POTENT UPPER LOW ROTATING EASTWARD OVER THE SOUTHERN GREAT
LAKES STATES CONTINUES TO EJECT NORTHEASTWARD THE AREA OF HEAVY RAIN
AND CONVECTION THAT IMPACTED FLORIDA ON WEDNESDAY WITHIN A 90-120
KNOT JET STREAK OVER THE EASTERN SEABOARD. RESIDUAL LIGHT SHOWER
ACTIVITY OVER THE SOUTHERN FORECAST AREA WILL RETAIN MENTION OF
SLIGHT CHANCE OF SHOWERS THROUGH EARLY MORNING.
IMPROVING WEATHER CONDITIONS WILL PREVAIL THROUGH TODAY AS COLD AND
DRY ADVECTION DEVELOPS WITHIN A NORTHWESTERLY FLOW...AS DEPICTED BY
THE 08Z TEMP/DWPT CONTRAST OF 48/46 AT TLH TO 60/59 AT TPA AND
69/67 AT FMY. THE COLDEST TEMPERATURES WILL BE OBSERVED FRI NIGHT
INTO SAT MORNING AS READINGS IN THE 30S PUSH SOUTHWARD ACROSS THE
NORTHERN COUNTIES WITH WIDESPREAD 40S ELSEWHERE...WILL DEFINITELY
BE A COLD MORNING FOR ANY HOLIDAY SHOPPERS CAMPING OUT EARLY FRI
AND SAT MORNING.
.LONG TERM...(SATURDAY NIGHT-WEDNESDAY)...OVERALL THE MODELS ARE
SIMILAR THROUGH THE PERIOD...BUT TIMING DIFFERENCES WITH RESPECT TO
THE NEXT STORM SYSTEM CONTINUE. DURING SUNDAY SURFACE HIGH PRESSURE
WILL MOVE OFF THE SOUTHEAST U.S. COAST AND CONTINUE TO RIDGE
WESTWARD ACROSS THE PENINSULA INTO MONDAY. THEN DURING THE MIDDLE OF
NEXT WEEK THE NEXT STORM SYSTEM WILL BE MOVING ACROSS THE EASTERN
U.S. WITH A NEW AREA OF LOW PRESSURE DEVELOPING OVER THE WESTERN
GULF. THIS NEW LOW IS EXPECTED TO MOVE EAST NORTHEAST ACROSS THE
SOUTHEAST STATES...BUT THE EXACT TIMING AND LOCATION OF THIS SYSTEM
VARY BETWEEN THE MODELS. FOR NOW HAVE CHOSEN TO LEAN TOWARD THE
SLOWER AND MORE RELIABLE ECMWF FORECAST FOR THE MIDDLE OF NEXT WEEK.
EITHER WAY IT STILL LOOKS LIKE THERE WILL BE A CHANCE OF SHOWERS
BEGINNING LATE MONDAY AND CONTINUING THROUGH WEDNESDAY. TEMPERATURES
WILL BE NEAR TO SLIGHTLY ABOVE NORMAL THROUGH THE PERIOD.
&&
.AVIATION...GRADUALLY IMPROVING CONDITIONS EXPECTED TODAY. AREAS OF
LOW CLOUDS AND FOG WILL CONTINUE TO CAUSE IFR/LOCAL LIFR CEILINGS
AND VISIBILITIES EARLY THIS MORNING...BUT CONDITIONS WILL IMPROVE
FROM NORTH TO SOUTH TO MVFR DURING THIS MORNING AND THEN VFR LATE
THIS MORNING INTO EARLY THIS AFTERNOON.
&&
.MARINE...COLD HIGH PRESSURE WILL BUILD OVER THE WATERS TODAY AND
INTO THE WEEKEND. PRESSURE GRADIENT WILL RESPOND ACCORDINGLY OVER
THE COASTAL AND OFFSHORE WATERS AND WILL POST A SMALL CRAFT ADVISORY
FOR TONIGHT AND SATURDAY MORNING.
&&
.FIRE WEATHER...DRY AND COLD ADVECTION WILL SPARK LOW RELATIVE
HUMIDITY VALUES AND WILL ISSUE A FIRE WEATHER WATCH FOR LATE MORNING
FRIDAY THROUGH AFTERNOON FOR INLAND SECTIONS. POTENTIAL EXISTS FOR
SIMILAR CONDITIONS ON SATURDAY BEFORE LOW-LEVEL MOISTURE BEGINS TO
SLOWLY INCREASE ACROSS THE AREA AHEAD OF THE NEXT WEATHER SYSTEM
TRACKING ACROSS THE GULF COAST REGION EARLY NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 72 48 65 47 / 5 5 5 5
FMY 77 53 68 46 / 20 5 5 5
GIF 73 48 66 43 / 5 5 5 5
SRQ 73 49 66 45 / 5 5 5 5
BKV 71 41 65 35 / 5 5 5 5
SPG 71 53 65 51 / 5 5 5 5
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...FIRE WEATHER WATCH FROM FRIDAY MORNING THROUGH FRIDAY AFTERNOON
FOR CHARLOTTE-CITRUS-DE SOTO-HARDEE-HERNANDO-HIGHLANDS-
HILLSBOROUGH-LEE-LEVY-MANATEE-PASCO-POLK-SARASOTA-SUMTER.
GULF WATERS...SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 10 AM
EST FRIDAY FOR BONITA BEACH TO ENGLEWOOD OUT 20 NM-BONITA BEACH TO
ENGLEWOOD OUT 20 TO 60 NM-ENGLEWOOD TO TARPON SPRINGS OUT 20 NM-
ENGLEWOOD TO TARPON SPRINGS OUT 20 TO 60 NM-TARPON SPRINGS TO
SUWANNEE RIVER OUT 20 NM-TARPON SPRINGS TO SUWANNEE RIVER OUT 20
TO 60 NM.
&&
$$
SHORT TERM/MARINE/FIRE WEATHER...10/LAMARRE
LONG TERM/AVIATION...69/CLOSE
