Area Forecast Discussion
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000
FXUS62 KKEY 231848
AFDKEY

AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
248 PM EDT TUE SEP 23 2014

.DISCUSSION...
.CURRENTLY...
THE VIEW FROM SPACE SHOWS THE STRONG SHORT WAVE PUSHING NORTHEAST
ALONG THE TROUGH NEAR THE CAROLINAS...WITH RIPPLES OF ENERGY MOVING
SOUTHEAST ACROSS THE CENTRAL GULF OF MEXICO. THE EARLIER SHOWERS AND
THUNDERSTORMS ARE MOVING EAST NORTHEAST ACROSS SOUTH FLORIDA AND THE
EASTERN STRAITS. WHILE INTERROGATING THE KBYX RADAR WE FIND SEVERAL
AREAS WITH MESO SCALE VORTICIES...MCV...LINGERING...ESPECIALLY WEST
OF THE KEYS AND MAINLAND MONROE COUNTY. THE TROUGH IS DRAPED ACROSS
THE SOUTHERN GULF OF MEXICO AND WESTERN CARIBBEAN WITH PLENTY OF
VORTICITY STRETCHING BETWEEN SOUTH FLORIDA AND THE YUCATAN. WINDS ARE
LIGHT AND VARIABLE OUTSIDE OF SHOWERS.

.FORECAST...
IN THE NEAR TERM EXPECT THE LINGERING MCV WILL HAVE OPPORTUNITY TO
INITIATE ADDITIONAL SHOWERS WITH A FEW THUNDERSTORMS OVERNIGHT.
GUIDANCE WOULD SUGGEST SHOWERS LIKELY...BUT THE GUIDANCE ALSO LOOKS
TO HAVE FEEDBACK ISSUES IN THE NEAR TERM. WILL TEMPER RAIN CHANCES
A BIT TO THE HIGH END OF CHANCE...50 PERCENT...OVERNIGHT THROUGH
THURSDAY.

TONIGHT AND WEDNESDAY A LARGE AND ROBUST RIDGE WILL BUILD OVER THE
EASTERN HALF OF THE UNITED STATES. THE SOUTHERN EDGE OF THIS RIDGE
WILL LAY UP ACROSS THE KEYS AREA WITH THE GRADIENT BUILDING.
ALTHOUGH THE RIDGE STRENGTHENS TO A 1037 MB HIGH...THE BULK OF THE
RIDGE WILL MOVE NORTHEAST OVER THE CANADIAN MARITIMES BEFORE
PEAKING. A TROUGH WILL DEVELOP IN THE LOW LEVELS EAST OF FLORIDA ON
WEDNESDAY...THE STRETCH NORTHEAST ACROSS THE DELMARVA THROUGH
THURSDAY NIGHT. THE NORTHWARD MOVEMENT OF THE RIDGE...ALONG WITH THE
WEAK LOW LEVEL TROUGH WILL LIMIT THE INCREASE IN BREEZES FOR THE
KEYS. WINDS WILL REMAIN MAINLY OUT OF THE EAST TONIGHT THROUGH THE
WEEKEND. EVEN WITH THE MITIGATING TROUGH...THE RIDGE WILL INCREASE
WINDS TO AT LEAST NEAR 15 MPH...15 KNOTS OVER THE MARINE
ENVIRONMENT...WEDNESDAY AND WEDNESDAY NIGHT. BY FRIDAY WE WILL RETURN
TO A MORE CLIMATOLOGICAL WEATHER PATTERN WITH CHANCE POPS.

&&

.MARINE...
A LARGE ROBUST RIDGE WILL BUILD OVER THE EASTERN UNITED STATES THEN
STRENGTHEN AS IT MOVES NORTHEAST TO THE CANADIAN MARITIMES BY WEDNESDAY
NIGHT. THE GRADIENT AROUND THE RIDGE MAY HAVE LIMITED EFFECT ON THE
KEYS AREA WINDS...BUT THERE REMAINS A POSSIBILITY FOR EPISODIC
CAUTIONARY STATEMENTS WEDNESDAY AND WEDNESDAY NIGHT. THE RIDGE MOVES
NORTHEAST AND WEAKENS THURSDAY THROUGH THE WEEKEND.

&&

.AVIATION...
A WET PATTERN IN PLACE ACROSS THE KEYS WILL MEAN A ROUND OR TWO OF
MVFR OR LOWER CONDITIONS WILL BE POSSIBLE AT THE ISLAND TERMINALS.
CURRENT SATELLITE AND RADAR TRENDS SUGGEST THAT VFR CONDITIONS WILL
PREVAIL FOR MUCH OF THE REMAINDER OF THE AFTERNOON INTO EVENING.
SURFACE WINDS WILL BE LIGHT OUT OF THE EAST.

&&

.CLIMATE...
ON THIS DATE IN KEYS WEATHER HISTORY...1931...2.10 INCHES OF RAIN
FELL IN KEY WEST ON SEPTEMBER 23RD. THIS SET THE DAILY RECORD FOR
RAINFALL IN KEY WEST WHICH STANDS 83 YEARS LATER. RAINFALL RECORDS
FOR KEY WEST DATE BACK TO 1971.

&&

.PRELIMINARY POINT TEMPS/POPS...
KEY WEST  79  87  79  88 / 50 50 50 50
MARATHON  79  87  79  88 / 50 50 50 50

&&

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

$$

PUBLIC/MARINE.........BWC
AVIATION/NOWCASTS.....11
DATA COLLECTION.......FLING

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