Southwest Florida Weather Forecast Discussion - Tampa Bay National Weather Service

000
FXUS62 KTBW 190801
AFDTBW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL
401 AM EDT SUN MAY 19 2013

.SYNOPSIS...
ALOFT - A LARGE SCALE TROUGH REACHED FROM THE CANADIAN ROCKIES TO 
THE U.S.CENTRAL ROCKIES...A RIDGE EXTENDED FROM THE WESTERN GULF
TO NORTH OF THE UPPER GREAT LAKES...A WEAK LOW OVER THE UPPER OHIO
VALLEY TROUGHED SOUTHEASTWARD TO THE CAROLINA COAST...AND A LOW WAS
JUST SOUTHEAST OF NEWFOUNDLAND. SURFACE - LOW PRESSURE IN WESTERN
KS HAD A DRY LINE SOUTH TO THE TX BIG BEND AND A FRONTAL BOUNDARY
THAT ARCED UP TO THE MID-WEST THEN SOUTHEASTWARD TO OFF THE MID-
ATLANTIC COAST...AND HIGH PRESSURE OVER MAINE AND NEW BRUNSWICK
RIDGED SOUTHWEST AND SOUTH TO THE GULF OF MEXICO AND THE NORTHERN
CARIBBEAN.

&&

.SHORT TERM (TODAY-TUESDAY)...
THE UPPER RIDGE TAKES AN EASTWARD TACK WITH IT/S AXIS REACHING THE 
APPALACHIAN RANGE WHILE THE OHIO VALLEY LOW MOVES TO THE 
MID-ATLANTIC COAST AS A OPEN WAVE MON THEN SLIDES ALONG THE COAST TO 
FL. THE HIGH PRESSURE OVER THE ATLANTIC RIDGES INTO THE GULF COAST 
REGION...MEANDERING IN THE VICINITY OF LATITUDE 30 NORTH BUT STAYING 
NORTH OF THE CWA. 

THE UPPER LEVEL TROUGHINESS WILL PROVIDE ENERGY THAT COMBINES WITH 
INCREASING MOISTURE...PRECIPITABLE WATER VALUES INCREASE FROM 1.2 
INCHES ON THE TBW SOUNDING LAST NIGHT TO AROUND 1.7 INCHES BY
TUE...ON EAST AND SE LOW LEVEL FLOW TO SUPPORT SLIGHT CHANCE TO
CHANCE SHOWERS AND STORMS. DAYTIME HEATING AND SEA BREEZES WILL
PROVIDE A FOCUS WITH TIMING FROM EARLY AFTERNOON TO EARLY EVENING
WITH THE HIGHEST ODDS MAINLY INLAND. THE SEA BREEZE WILL BE MOST
ROBUST TODAY BUT MORE LIMITED MON-TUE AS THE GRADIENT TIGHTENS
SOME. TEMPERATURES WILL RUN WITHIN A DEGREE OR TWO...PLUS OR
MINUS...OF NORMAL.

.LONG TERM (TUESDAY NIGHT-SATURDAY)...
SURFACE HIGH PRESSURE WILL BE IN PLACE ACROSS THE AREA THROUGH 
WEDNESDAY WITH THE RIDGE AXIS NORTH OF THE AREA...AS A WEAK TROUGH 
REMAINS IN PLACE ALOFT. GENERALLY E/SE WINDS WILL BE IN PLACE WITH A 
SEA BREEZE DEVELOPING WEDNESDAY AFTERNOON. AMPLE MOISTURE WILL ALLOW 
FOR SCATTERED AFTERNOON/EVENING THUNDERSTORMS TO DEVELOP EACH DAY 
ALONG SEA BREEZE AND OUTFLOW BOUNDARIES WITH THE BEST CHANCES 
INLAND. HAVE KEPT RAIN CHANCES AT 30 PERCENT COASTAL-50 PERCENT 
INLAND WITH THE CONVECTION. TEMPERATURES WILL BE IN THE MID 
60S-LOWER 70S WEDNESDAY MORNING AND IN THE MID 80S COASTAL TO LOWER 
90S INLAND WEDNESDAY AFTERNOON. 

FOR WEDNESDAY NIGHT AND THURSDAY...AN AREA OF WEAK LOW PRESSURE WILL 
MOVE OVER THE AREA SHIFTING WINDS TO THE WEST THROUGH THE DAY AND 
PULLING IN A LITTLE DRIER AIR BEHIND IT. RAIN CHANCES WILL BE 30-40 
PERCENT FOR THURSDAY AFTERNOON. LOWS WILL AGAIN BE IN THE MID 60S TO 
LOWER 70S...WITH HIGHS IN THE UPPER 80S TO LOWER 90S. 

FOR THURSDAY NIGHT THROUGH SATURDAY...HIGH PRESSURE WILL BUILD OVER 
THE EASTERN GULF OF MEXICO KEEPING GENERALLY W/NW FLOW IN PLACE 
ACROSS THE AREA. RAIN CHANCES WILL BE 20-30 PERCENT WITH THE BEST 
CHANCES INLAND. LOWS CONTINUE IN THE MID 60S TO LOWER 70S...WITH 
HIGHS IN THE UPPER 80S TO LOWER 90S.

&&

.AVIATION...
PATCHY FOG WILL BE POSSIBLE CAUSING TEMPO MVFR CONDITIONS FROM 
09-13Z ACROSS THE TERMINALS...OTHERWISE VFR WITH LIGHT AND VARIABLE 
WINDS. AFTER 14Z...VFR CONDITIONS WILL PREVAIL AS SKIES BECOME 
PARTLY CLOUDY AND A SEABREEZE DEVELOPS GENERALLY BETWEEN 16-18Z AT 
THE COASTAL TERMINALS. SCATTERED THUNDERSTORMS WILL BE POSSIBLE 
AFTER 19Z...CAUSING TEMPO MVFR CONDITIONS. BEST CHANCES AT KLAL. 

&&

.MARINE...
ATLANTIC HIGH PRESSURE WILL RIDGE WESTWARD...WITH AN AXIS NORTH OF 
THE COASTAL WATERS...THROUGH WED THEN BEGIN TO SLIDE OFF TO THE EAST 
THU AS A BROAD AND WEAK LOW PRESSURE AREA MOVES INTO THE GULF 
REGION. EAST AND SE WINDS...BUT WITH SOME AFTERNOON SEA BREEZES...
OF 10 KNOTS GRADUALLY VEER TO WEST AND NW BY MID-WEEK.

&&

.FIRE WEATHER...
MINIMUM RELATIVE HUMIDITY VALUES STAY ABOVE CRITICAL LEVELS
THROUGH THE WORK WEEK. 

&&

.PRELIMINARY POINT TEMPS/POPS...
TPA  88  73  87  71 /  30  20  40  20 
FMY  90  71  90  70 /  30  20  40  20 
GIF  90  70  88  70 /  40  20  50  20 
SRQ  86  70  88  70 /  30  20  30  20 
BKV  89  67  88  66 /  30  20  40  20 
SPG  86  74  85  73 /  30  20  30  20 

&&

.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.

&&

$$

SYNOPSIS/SHORT TERM/MARINE/FIRE WEATHER...09/RUDE
LONG TERM/AVIATION...24/COLSON

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