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FXUS62 KKEY 280208
AFDKEY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
1008 PM EDT THU AUG 27 2015

.DISCUSSION...
KBYX RADAR SHOWS SEVERAL CLUSTERS OF SHOWERS WITH EMBEDDED
THUNDERSTORMS ARE PERSISTING ALONG THE SOUTHWESTERN EDGE OF THE KEYS
SERVICE AREA. OUTFLOW BOUNDARIES ARE PUSHING ISOLATED TO SCATTERED
EXTENSIONS OF THE STORMS TOWARDS THE LOWER KEYS AT THIS HOUR. LATE
EVENING IR SATELLITE IMAGES SHOW THE SHIELD FROM THIS ACTIVITY
ENCROACHING ON THE ISLAND CHAIN ALREADY. A LIGHT SURFACE WIND
REMAINS IN PLACE ALONG WITH WARM AND HUMID CONDITIONS.

THE LATE EVENING LOCAL SOUNDING SHOWS LIGHTER BREEZES VEERING THROUGH
ABOUT 4000 FEET. A DEEP AND MORE MODERATE SOUTHWESTERLY BREEZE
EXTENDS WELL INTO THE TROPOSPHERE ABOVE THAT. WE REMAIN QUITE
MOIST...AND PARAMETERS SUGGEST THAT CONVECTION IS A FAIR BET THROUGH
THE OVERNIGHT PERIOD...ESPECIALLY WITH THE ACTIVITY AND ASSOCIATED
BOUNDARIES CURRENTLY UPSTREAM OF THE ISLAND CHAIN. A HIGH CHANCE
PROBABILITY OF MEASURABLE PRECIPITATION IS STILL A GOOD BET THROUGH
THE FIRST PERIOD. IF THE INITIAL BOUNDARY WAS MORE ACTIVE...I MIGHT
HAVE NUDGED THAT UPWARD. BUT A 50 PERCENT LOOKS GOOD FOR NOW. WINDS
MAY ACQUIRE A SOUTHERLY COMPONENT LATER IN THE OVERNIGHT PERIOD...BUT
WILL KEEP VARIABLE ADVERTISED BASED ON THE LATEST SET OF OBSERVATIONS
IN AND AROUND THE ISLAND CHAIN.

&&

.MARINE...
AS WITH THE ZONES...WINDS MAY ACQUIRE A MORE SOUTHERLY COMPONENT
LATER IN THE OVERNIGHT PERIOD. BUT THERE REMAINS ENOUGH DIRECTIONAL
VARIABILITY IN THE NEAR TERM TO NOT MAKE A CHANGE ON THE UPCOMING
MARINE UPDATE. MARINE INTERESTS IN THE FLORIDA KEYS SHOULD STAY
ABREAST OF THE LATEST FORECASTS ON WHAT IS STILL TROPICAL STORMS
ERIKA IN THE NORTHEASTERN CARIBBEAN SEA. THE LATEST OFFICIAL TRACK
HAS ERIKA MOVING THROUGH THE BAHAMAS SATURDAY AND EARLY SUNDAY...AND
NEAR THE SOUTHEAST FLORIDA COAST BY EARLY MONDAY.

&&

.AVIATION...
EXPECT VFR CONDITIONS OVERNIGHT AT BOTH THE KEY WEST AND MARATHON
TERMINALS WITH SHOWERS AND THUNDERSTORMS DEVELOPING LATE. AN UPPER
LEVEL TROUGH OVER THE EASTERN GULF OF MEXICO WILL ADD VENTILATION
OVER THE VERY MOIST LOW TO MID LEVEL SOUTHWESTERLY FLOW. BASED ON
THIS WOULD EXPECT LINGERING BOUNDARIES TO BECOME ACTIVE AFTER 07Z
TO 08Z ALONG THE ISLAND CHAIN...THEN SPREADING NORTH AFTER SUNRISE.
WINDS WILL BE VARIABLE AND LIGHT OUTSIDE OF SHOWERS AND
THUNDERSTORMS...WHICH MAY PRODUCE WIND GUSTS IN EXCESS OF 30 KNOTS.
ALSO...SHOWERS AND THUNDERSTORMS WILL BE ELEVATED WHICH WILL PRODUCE
MVFR TO IFR CEILINGS AND / OR VISIBILITIES ONLY DURING EVENTS OVER
THE TERMINALS.

&&

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

&&

$$

PUBLIC/MARINE.........04
AVIATION/NOWCASTS.....BWC
DATA COLLECTION.......CHESSER

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