Special Marine Warning 4, NWS Key West, FL

AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
351 PM EST WED JAN 11 2012

.DISCUSSION...
.CURRENTLY...
WINDS ACROSS THE ARE CURRENTLY DECREASING RAPIDLY WITH C-MAN
STATIONS WEST OF THE MIDDLE KEYS AND FLORIDA BAY AT 10 TO 15
KNOTS...STILL 15 TO 20 KNOTS SOUTH OF THE UPPER KEYS...ALL OUT OF
THE SOUTHWEST. THE LINE OF SHOWERS ASSOCIATED WITH THE DECAYING FRONT
HAS STRETCHED OUT FROM SOUTHWEST TO NORTHEAST AND THE SHOWER ACTIVITY
HAS DIMINISHED GREATLY. RAINFALL RATES WITH THE LINE TO THE NORTH ARE
ONE TENTH TO ONE QUARTER OF AN INCH. THE PUSH FOR THE FRONT HAS
LIFTED OUT TO THE NORTHEAST WITH THE UPPER LOW TREKKING NORTHWARD
OVER GEORGIA AT THIS HOUR. ANOTHER FRONT IS MOVING DOWN THE SOUTHERN
EDGE OF THE FRONT RANGE THROUGH THE NORTHERN TEXAS PANHANDLE AND IS
MENTIONED BELOW.

.FORECAST...
THE UPPER SUPPORT FOR THE WEAK BOUNDARY PASSING THROUGH THE KEYS AREA
THIS EVENING IS MOVING EAST OF THE FLORIDA PENINSULA THIS AFTERNOON.
THE SIGNIFICANT WEATHER ASSOCIATED WEATHER WITH THIS BOUNDARY IS THE
THUNDERSTORMS BEYOND 20 NM SOUTH OF REBECCA SHOAL MOVING EASTWARD
NEAR 25 KNOTS. EXPECTING THIS AREA TO TRAVERSE THE STRAITS THROUGH
THIS EVENING WHILE THE ONLY LIGHT RAIN EXISTS NORTH AND EAST ALONG
THE BOUNDARY. HAVE ADJUSTED POPS DOWN TONIGHT AS THE LINE OF LIGHT
SHOWERS IS STRETCHING OUT AND GAPS ARE EVIDENT FROM THE KBYX RADAR
PRESENTATIONS.

THE MOISTURE ASSOCIATED WITH THIS BOUNDARY WILL HAVE A HARD TIME
CLEARING THE AREA DUE TO ANOTHER REINFORCING FRONT THAT IS CURRENTLY
CROSSING THE NORTHERN TEXAS PANHANDLE ON ITS WAY EASTWARD.
TEMPERATURES WILL DROP SLIGHTLY TONIGHT THROUGH FRIDAY...THEN WITH
THE NEXT FRONT EXPECT MUCH DRIER AIR AND COOLER TEMPERATURES SUNDAY
THROUGH WEDNESDAY. THIS NEXT FRONT IS EXPECTED TO ARRIVE NEAR THE
KEYS LATE SATURDAY AFTERNOON AND WILL BE ACCOMPANIED BY A STRONGER
RIDGE THAT WILL PUSH THE FRONT THROUGH CUBA BY SUNDAY NIGHT. WINDS
AHEAD OF THIS FRONT WILL BE QUITE LIGHT THEN INCREASE QUICKLY AS THE
RIDGE TAKES OVER ON SUNDAY. THEREAFTER MODERATE TO FRESH NORTH TO
NORTHEAST WINDS WILL TAKE OVER THROUGH MONDAY NIGHT...THEN GRADUALLY
DECREASE THROUGH TUESDAY NIGHT...WITH LITTLE AVAILABLE MOISTURE
AROUND EXPECT NEAR ZERO POPS SUNDAY THROUGH TUESDAY NIGHT. THE RIDGE
WILL MOVE OUT TO THE NORTHEAST GRADUALLY WEDNESDAY ALLOWING LOW LEVEL
MOISTURE TO BUILD OVER THE AREA...AND USHERING IN A SLIGHT CHANCE FOR
SHOWERS.

&&

.MARINE...
A SMALL CRAFT ADVISORY IS IN EFFECT FOR THE WESTERN STRAITS...AND
GULF WATERS NORTH OF THE LOWER KEYS. AS THE REMAINS OF A WEAK FRONTAL
ZONE PASSES THE KEYS THIS EVENING EXPECT THE WIND TO DECREASE QUICKLY
AS IT CLEARS THE AREA. THE MAIN CONCERN FOR MARINERS IS MOVING
EASTWARD BEYOND 20 NM SOUTH OF THE ISLAND CHAIN. ALSO EXPECT TO DROP
THE ADVISORY BY 10 PM AT THE LATEST...AND WILL UPDATE AS NEEDED.
OTHERWISE...NO CAUTIONARY OR ADVISORY STATEMENTS ARE EXPECTED TONIGHT
THROUGH AT LEAST FRIDAY NIGHT.

&&

.AVIATION...
SHOWERS ASSOCIATED WITH A COLD FRONT MOVING THROUGH THE FLORIDA KEYS
WILL PRODUCE TEMPORARY MVFR CONDITIONS AT BOTH THE KEY WEST AND
MARATHON TERMINALS THROUGH THE REMAINDER OF THIS AFTERNOON AND EARLY
EVENING. CEILINGS AROUND FL020 AND VISIBILITY REDUCED TO AROUND 3 NM
ARE POSSIBLE WITH THE FRONT...AS WELL AS SOUTHERLY WIND GUSTS
CAUSING OCCASIONAL CROSSWINDS NEAR 20 KNOTS. SURFACE WINDS WILL BE
MAINLY FROM THE SOUTH SOUTHWEST AT NEAR 10 KNOTS AND VEER TO
WESTERLY NEAR 5 KNOTS THIS EVENING AFTER THE FRONT HAS PASSED
THROUGH THE AREA. VFR CONDITIONS ARE EXPECT TO PREVAIL AT BOTH
ISLAND TERMINALS THROUGH TONIGHT AND OVERNIGHT.

&&

.CLIMATE...
THIS DATE IN KEYS WEATHER HISTORY...1886...THE HIGH TEMPERATURE IN
KEY WEST WAS 55 DEGREES...SETTING THE DAILY RECORD FOR COLD MAXIMUM
TEMPERATURE...WHICH STANDS 126 YEARS LATER.

&&

.PRELIMINARY POINT TEMPS/POPS...
KEY WEST  70  77  67  74 / 20 30 20 20
MARATHON  70  78  67  75 / 20 30 20 20

&&

.KEY WATCHES/WARNINGS/ADVISORIES...
FL...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR FLZ077-FLZ078.

GM...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR GMZ032-GMZ033-
     GMZ034-GMZ044-GMZ054-GMZ055-GMZ074-GMZ075.

&&

PUBLIC/MARINE.........BWC
AVIATION/NOWCASTS.....DEVANAS
DATA COLLECTION.......PARKE

VISIT US ON THE WEB AT WWW.WEATHER.GOV/KEYWEST