Area Forecast Discussion
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000
FXUS62 KKEY 061840
AFDKEY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
245 PM EDT WED MAY 6 2015

.DISCUSSION...IN THE MID AND UPPER LEVELS...(500-200 MB)...LATEST
AVAILABLE IR IMAGERY AS OF 200 PM OVERLAID WITH MODEL STREAMLINE
ANALYSIS DETAILS THE MAIN AXIS OF MID AND UPPER TROUGH FROM THE
MIDDLE OHIO VALLEY SOUTH SOUTHEASTWARD TO THE FLORIDA
PENINSULA...BUT 25 TO 35 KNOT WINDS AT 250 MB ROUNDS THE BASE OF THE
TROUGH ACROSS CUBA...THEN STREAM NORTHWARD TO OVER THE NORTHERN
BAHAMAS. MIDDLE AND UPPER LOW PRESSURE IS EAST OF THE FLORIDA
PENINSULA.

AT THE SURFACE AND IN THE LOWER TO MIDDLE LEVELS...SURFACE TO 700
MB...AS OF 200 PM...BROAD LOW PRESSURE IS LOCATED ACROSS THE
NORTHERN BAHAMAS NORTHWARDS TO NORTHWEST OF THE ABACOS ISLANDS. THE
NATIONAL HURRICANE CENTER IS MONITORING THIS LOWER PRESSURE AREA FOR
POSSIBLE TROPICAL OR SUBTROPICAL DEVELOPMENT BY THURSDAY FOR FRIDAY.
THE FLORIDA KEYS ARE NOW IN A COL ZONE BETWEEN THE DEVELOPING LOW
PRESSURE EAST OF FLORIDA...AND RIDGING OVER THE GULF OF MEXICO.

.CURRENTLY...SKIES ARE SUNNY ACROSS THE ISLANDS AND ADJOINING
WATERS. THE KEYS ARE IN A COL ZONE WITH VARIABLE WINDS AROUND 5 MPH
OR LESS OVER THE ISLANDS AND 5 KNOTS OR LESS ACROSS THE WATERS.
GIVEN LOWER TO MID LEVEL SUBSIDENCE...SEA BREEZE CONVECTION HAS HAD
A TOUGH TIME GETTING GOING OVER DADE AND MAINLAND MONROE COUNTY.
ISLAND CLOUD LINES HAVE BEEN TWHARTED. TEMPERATURES ACROSS THE
ISLANDS ARE AROUND 80 WITH DEWPOINTS IN THE UPPER 60S.

.SHORT TERM...TONIGHT AND THURSDAY...BROAD AREA OF LOW PRESSURE IN
TANDEM WITH MID AND UPPER TROUGH EAST OF FLORIDA IS GETTING ITS ACT
TOGETHER...BUT AS IT DOES IT WILL CONTINUE TO PULL NORTHWARDS TODAY
AWAY FROM OUR AREA. AS SUCH...ADDITIONAL SUBSIDENCE HAS BEEN
INTRODUCED ACROSS THE AREA IN THE LOWER TO MIDDLE LEVELS FOR TONIGHT
AND THURSDAY. SKIES WILL BE MOSTLY CLEAR...BUT WILL LEAVE IN A
SLIGHT CHANCE FOR SHOWERS...WITH THE BEST CHANCE...ALBEIT
SLIGHT...ACROSS THE NORTHERNMOST UPPER KEYS...WHERE WEAK LOWER LEVEL
WEST WINDS COULD BRING ACROSS A LOW TOPPED SHOWER OR TWO.

THURSDAY NIGHT THROUGH MONDAY...WEAKER RIDGING PROGGED TO RETURN
NORTH OF THE KEYS. FORECAST SOUNDINGS REMAIN SLIGHTLY DRY...WITH
PWAT(PRECIPITABLE WATER) BETWEEN 1.25 AND 1.50 INCHES. LIGHT TO
GENTLE EAST OR EAST TO SOUTHEAST WINDS WILL FAVOR ISOLATED
SHOWERS...AS THE ALIGNMENT IS NOT PERFECT FOR CUMULUS LINE
CONVECTION. HIGH TEMPERATURES IN THE MID 80S AND LOWS IN THE MID 70S
ARE ANTICIPATED. AS A RESULT SLIGHT CHANCE POPS...20% WILL BE
MAINTAINED IN THE GRIDS

EXTENDED...FOR MONDAY THROUGH WEDESDAY...SLIGHTLY STRONGER RIDGING
IS INDICATED ACROSS THE PENINSULA...SO WINDS WILL BE GENTLE OR
GENTLE TO MODERATE. BOUNDARY LAYER MOISTURE NEAR NORMAL WOULD FAVOR
MORE LATE NIGHT/EARLY MORNING ISOLATED SHOWERS...SO 20 PERCENT POP
WILL REMAIN IN THE GRIDS.

&&

.MARINE...NO ADVISORIES AND NO HEADLINES THRU THE PERIOD. AN AREA OF
LOW PRESSURE ACROSS THE NORTHERN BAHAMAS WILL MOVE NORTHWARD TONIGHT
THROUGH THURSDAY. THEREAFTER...WEAK RIDGING WILL REMAIN ACROSS SOUTH
FLORIDA THROUGH EARLY NEXT WEEK.

&&

.AVIATION...VFR WILL PREVAIL AT THE EYW AND MTH TERMINALS THROUGH
TONIGHT. EXPECT VARIABLE WINDS AND NEARLY NIL RAIN CHANCES.

&&

.CLIMATE... ON THIS DATE IN KEYS WEATHER HISTORY...

06-MAY IN 1991, THE DAILY RECORD HIGH TEMPERATURE OF 89F WAS LAST
RECORDED. IN 1921, THE DAILY RECORD COLD HIGH TEMPERATURE OF 75F WAS
LAST RECORDED. IN 1984, THE DAILY RECORD WARM LOW TEMPERATURE OF 81F
WAS RECORDED. IN 1992, THE DAILY RECORD LOW TEMPERATURE OF 67F WAS
LAST RECORDED. IN 1972, THE DAILY RECORD RAINFALL OF 1.49" WAS
RECORDED.

&&

.PRELIMINARY POINT TEMPS/POPS...
KEY WEST  71  82  75  83 / 10 10 20 20
MARATHON  73  83  75  85 / 10 10 20 20

&&

.KEY WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GM...NONE.
&&

$$

PUBLIC/MARINE.........FUTTERMAN
AVIATION/NOWCASTS.....CLR
DATA COLLECTION.......CHESSER

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