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000
FXUS62 KMFL 201837
AFDMFL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
237 PM EDT MON MAY 20 2013

.SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...
A SOUTHERN STREAM MID LEVEL TROUGH THAT MOVED ACROSS THE SOUTHERN
STATES THE PAST FEW DAYS IS NOW GETTING CUT OFF OVER THE FLORIDA
PENINSULA AS A STRONGER NORTHERN STREAM TROUGH CUTS OFF OVER THE
NORTHERN PLAINS STATES. THE LOW OVER FLORIDA WILL MOVE VERY LITTLE
THROUGH THIS PERIOD WHICH HAS CAUSED THE ATMOSPHERE TO BECOME VERY
UNSTABLE AS 500 MB TEMPERATURES HAVE COOLED FROM -6.7 CELSIUS FROM
LAST EVENING TO -7.5 THIS MORNING. AT THE SURFACE, A RIDGE OF HIGH
PRESSURE WILL ALSO REMAIN NEARLY STATIONARY FROM THE SOUTHEAST
STATES STRETCHING INTO THE ATLANTIC. ATMOSPHERIC MOISTURE HAS
ALSO BEEN ON THE INCREASE WITH PWAT GOING UP TO 1.66 INCHES THIS
MORNING WHICH IS CLOSE TO AVERAGE FOR THE TRANSITIONAL PERIOD
GOING INTO THE LAST HALF OF MAY. EVEN THOUGH OVERALL MOISTURE IS
NOT TERRIBLY IMPRESSIVE, THE MAIN ISSUE IS THE COLD TEMPERATURES
ALOFT ALONG WITH VERY SLOW STORM MOTION AS LOW LEVEL FLOW IS FROM
THE SOUTHEAST AND FLOW ABOVE 10K IS FROM THE WEST. THUS, WITH THE
PATTERN CHANGING VERY LITTLE THE NEXT 48 HOURS THERE WILL BE A
CONTINUED CHANCE OF THUNDERSTORMS MAINLY DURING THE LATE MORNING
INTO THE EARLY EVENING HOURS.

.LONG TERM (THURSDAY THROUGH MONDAY)...
IN THE EXTENDED PERIOD, THE NORTHERN STREAM TROUGH WILL DEEPEN AND
SLOWLY DRIFT TO THE SOUTHEAST WHILE THE LOW OVER THE PENINSULA
GETS PHASED IN WITH THIS DEEPENING TROUGH AND LIFTS TO THE
NORTHEAST ON THURSDAY AND FRIDAY. THE DEEPENING TROUGH WILL ALSO
FORCE A COLD FRONT TO MOVE INTO NORTH FLORIDA ON FRIDAY AND THEN
MOVE SLOWLY SOUTH DOWN THE PENINSULA OVER THE WEEKEND WITH A SLOW
DRYING TREND. THERE WILL BE HOWEVER ENOUGH RESIDUAL MOISTURE AND
INSTABILITY ACROSS SOUTH FLORIDA FOR LOW CHANCES FOR
AFTERNOON/EVENING THUNDERSTORMS EACH DAY.

&&

.AVIATION...
QUITE AN ACTIVE AFTERNOON AND EVENING AHEAD OF US FOR THE EASTERN
TERMINALS. SHOWERS AND THUNDERSTORMS WILL CONTINUE DEVELOPING WHILE
MOVING IN ALL DIRECTIONS. ALTHOUGH MOST OF THE ACTIVITY IS REMAINING
WEST OF THE TERMINALS...A FEW COULD GET CLOSE ENOUGH...THEREFORE
AMENDMENTS ARE EXPECTED. SOUTHEASTERLY FLOW WILL PREVAIL FOR THESE
TERMINALS...WITH STRONG GUSTS EXPECTED AS STORMS APPROACH. SHOWERS
WILL CONTINUE LINGERING THROUGH THE NIGHT...SO VCSH WAS KEPT AT ALL
EASTERN TERMINALS.

FOR KAPF...SEA BREEZE ALREADY DEVELOPED AND PUSHED INLAND...AND
PREVAILING UNTIL 18-01Z. AFTER THAT...EASTERLY FLOW WILL PREVAIL
WITH NO OTHER CONCERNS.

&&

.MARINE...
AN EAST TO SOUTHEAST WIND OF 15 KNOTS OR LESS WILL CONTINUE
THROUGH THE END OF THE WEEK WITH SEAS GENERALLY LESS THAN 4 FEET.

&&

.FIRE WEATHER...
NO PROBLEMS OR CONCERNS WITH AMPLE TROPICAL MOISTURE REMAINING
THROUGH THE MIDDLE OF THE WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH  72  84  74  84 / 40 60 40 50
FORT LAUDERDALE  75  85  75  85 / 40 50 40 40
MIAMI            74  86  74  86 / 40 50 30 40
NAPLES           70  86  70  85 / 30 40 20 30

&&

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&

$$

DISCUSSION/MARINE/FIRE...30/KOB
AVIATION/RADAR...84/AK