Area Forecast Discussion
Issued by NWS

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS62 KKEY 020218
AFDKEY

AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
1015 PM EDT FRI AUG 1 2014

.DISCUSSION...
FROM MID AFTERNOON THROUGH THIS EVENING...SEVERAL EPISODES OF BROKEN
SEGMENTED CLOUD LINE CELLS MIGRATED WEST SOUTHWESTWARD WITH THE
MAJORITY OF THE ACTIVITY STAYING JUST OFFSHORE OR CLIPPING THE
SOUTHERN OR NORTHERN PORTION OF THE ISLAND CHAIN. DESPITE A VERY
FAVORABLE BACKING AND LIGHT WIND PROFILE...POCKETS OF DRIER AIR AND
MODEST INSTABILITY KEPT CELLS MODEST AT BEST. CURRENTLY...LOCAL
RADARS ARE DETECTING ISOLATED SHOWERS AND AN OCCASIONAL BRIEF
THUNDERSTORM TRACKING WEST SOUTHWESTWARD THROUGH OUR COUNTY WARNING
AREA. SURFACE WISE...A NEBULOUS WESTERN ATLANTIC RIDGE AXIS LIES
JUST NORTH OF THE ISLAND CHAIN...RESULTING IN A PREDOMINATE EAST
WIND OF 5 KNOTS OR LESS. OTHERWISE...OUR EVENING SOUNDING REVEALS
AVERAGE MOISTURE (PWAT 1.92 INCHES) BUT WITH A COUPLE OF SOMEWHAT
DRY POCKETS (TEMP/DP DIFFERENTIAL OF 5 AND 6 DEGREES C) AT 950 AND
850 MB RESPECTIVELY. A LIGHT NORTHEAST TO EAST TRAJECTORY REACHES
WELL UP INTO THE TROPOSPHERE...BEFORE TURNING SOUTHEAST AND
INCREASING ABOVE.

.SHORT TERM (REST OF TONIGHT)...
WITH OUR AREA LYING ON THE SOUTHERN PERIPHERY OF A DEEP LAYERED
WESTERN ATLANTIC RIDGE AND A NORTH-SOUTH ORIENTED TROUGH EXTENDING
FROM THE CENTRAL BAHAMAS SOUTHWARD INTO THE NORTH CENTRAL CARIBBEAN
SEA...A LIGHT NORTHEAST TO EAST TRAJECTORY WILL PREVAIL ACROSS OUR
AREA FOR AT LEAST THE NEXT 24 HOURS. GIVEN AMPLE MOISTURE AND
SEVERAL LEFTOVER BOUNDARIES...A SUBTLE INCREASE IN THE LOW LEVEL
FLOW SHOULD GENERATE SCATTERED SHOWERS AND PERHAPS A FEW
THUNDERSTORMS IN COUNTY WARNING AREA. UNDER PARTLY CLOUDY SKIES WITH
LIGHT EAST OR CALM WINDS...LOW TEMPERATURES WILL RANGE BETWEEN THE
MID 70S TO LOWER 80S. SINCE THE CURRENT FORECAST HANDLES THE
SITUATION WELL...NO CHANGES ARE PLANNED.

&&

.MARINE...
OUR EVENING RAWINDSONDE DEPICTED NORTHWEST WINDS OF 3 KNOTS AT 1 AND
2 THOUSAND FEET RESPECTIVELY...WHILE THE LATEST KBYX VWP SHOWS
NORTHEAST AT 10 KNOTS. WITH THE SPLINTERED WESTERN ATLANTIC RIDGE
LYING JUST NORTH OF OUR AREA...MOSTLY EAST WINDS OF 5 TO 10 KNOTS
CAN BE EXPECTED ON ALL KEYS COASTAL WATERS.

&&

.AVIATION...
EXPECTING MOSTLY  VFR CONDITIONS TO CONTINUED THROUGH THE TAF PERIOD
AT BOTH THE KEY WEST AND MARATHON ISLAND TERMINALS. THERE WILL BE
BRIEF PERIODS OF MVFR AND POTENTIALLY MORE BRIEF PERIODS OF IFR
CONDITIONS DUE TO AMPLE INSTABILITY SHOWING ON THE EVENING
SOUNDING...THE ONE PIECE OF THE PUZZLE MISSING IS MOISTURE. WINDS
WILL NOT BE AN ISSUE DUE TO THE WEAK PRESSURE FIELD OVER THE KEYS
AREA. WILL KEEP VCSH IN THE TAF WITH AMENDMENTS ISSUED AS CONDITIONS
WARRANT.

&&

.CLIMATE...
ON THIS DATE IN KEYS WEATHER HISTORY...AUGUST FIRST 1971...THE LOW
TEMPERATURE IN KEY WEST WAS 71 DEGREES...SETTING THE DAILY RECORD
MINIMUM TEMPERATURE. THIS RECORD REMAINS STANDING AFTER 44 YEARS.
TEMPERATURE RECORDS FOR KEY WEST DATE BACK TO 1872.

&&

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

&&

$$

PUBLIC/MARINE/FIRE/CLIMATE/DIGITAL...APA
AVIATION/NOWCASTS....................BWC

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



















USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.