Area Forecast Discussion
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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 291343
AFDKEY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
945 AM EDT SUN MAR 29 2015

.DISCUSSION...
.CURRENTLY...EARLY VISIBLE SATELLITE PHOTOGRAPHS SHOW SKIES ARE
MOSTLY SUNNY WITH ONLY PATCHES OF WISPY CIRRUS WITHIN THE SUBTROPIC
JET STREAM WHICH REMAINS ALONG OUR LATITUDE. TEMPERATURES RANGE FROM
59 DEGREES IN KEY LARGO AND UPPER MATECUMBE TO 67 DEGREES AT KEY
WEST. AND OF COURSE...LOCAL RADARS ARE VOID OF ANY PRECIPITATION
ECHOES IN OUR COUNTY WARNING AREA. SURFACE WISE...A VERY FORMIDABLE
AND EXPANSIVE REGION OF HIGH PRESSURE IS CENTERED OVER THE MID
ATLANTIC AND SOUTHEAST UNITED STATES...WITH A RIDGE AXIS REACHING
DOWN THE SPINE OF THE FLORIDA PENINSULA. ACROSS OUR COASTAL
WATERS...WINDS ARE NORTH TO NORTHEAST AT 15 TO 20 KNOTS.
OTHERWISE...OUR MORNING SOUNDING REVEALS LIMITED MOISTURE (PWAT .56
INCHES) WITH A COUPLE OF STABLE LAYERS BELOW 700 MB. MODERATE TO
FRESH NORTH TO NORTHEAST WINDS QUICKLY TURN WEST SOUTHWEST AND
INCREASE SHARPLY ABOVE 500 MB.

.SHORT TERM UPDATE...A STRENGTHENING...DEEP AND MASSIVE ANTICYCLONE
CENTERED OVER THE EASTERN HALF OF THE GULF OF MEXICO...NORTHWARD UP
THE ENTIRE EASTERN UNITED STATES WILL RESULT IN STRONG LARGE SCALE
SUBSIDENCE ACROSS OUR REGION. WITH THE SHARP ANTICYCLONIC
FLOW...SCANT MOISTURE WITH ONLY INTERMITTENT PATCHES OF CIRRUS CAN
BE EXPECTED FOR THE BALANCE OF TODAY. HOWEVER...DESPITE PLENTY OF
INSOLATION...A PREDOMINATE NORTHEAST FLOW WILL KEEP HIGH
TEMPERATURES PRIMARILY IN THE MID 70S ALONG THE ISLAND CHAIN.
HENCE...HAVE UPDATED TO DROP THE HIGH TEMPERATURES FROM THE UPPER
70S TO THE MID 70S...AND INSERTED NEAR 15 MPH AND GUSTY.

&&

.MARINE...OUR MORNING RAWINDSONDE INDICATED NORTH TO NORTHEAST WINDS
OF 17 AND 18 KNOTS AT 1 AND 2 THOUSAND FEET WHICH COINCIDES WITH THE
KBYX VWP. WITH THE LARGE AND SPRAWLING AREA OF HIGH PRESSURE
CENTERED OVER THE MID ATLANTIC AND SOUTHEAST STATES PRESSING
SOUTHEASTWARD...WINDS WILL TURN MOSTLY NORTHEAST THIS AFTERNOON AND
EVENING. MEANWHILE...HEATING ON THE SOUTH FLORIDA PENINSULA COMBINED
WITH WATER TEMPERATURES AVERAGING IN THE LOWER TO MID 70S NORTH OF
THE MIDDLE KEYS AND ON FLORIDA BAY WILL DISRUPT THE FLOW RESULTING
IN A SLACKENING OF WINDS. WITH THAT SAID...AN EXERCISE CAUTION
HEADLINE WILL BE KEPT FOR THE REST OF OUR MARINE DISTRICT.

&&

.AVIATION...REST OF TODAY...VFR CONDITIONS WILL PREVAIL AT BOTH THE
KEY WEST INTERNATIONAL AND MARATHON FLORIDA KEYS AIRPORTS. SURFACE
WINDS WILL AVERAGE FROM 040 DEGREES AOA 12-14 KNOTS WITH GUSTS
BETWEEN 18 AND 22 KNOTS. SOME CIRRUS WILL PASS BY BET FL200-300.

&&

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

&&

$$

PUBLIC/MARINE.........APA
AVIATION/NOWCASTS.....DAF
DATA COLLECTION.......EV

VISIT US ON THE WEB AT WEATHER.GOV/KEY

FOLLOW US ON FACEBOOK AND TWITTER AT...

WWW.FACEBOOK.COM/NWSKEYWEST
WWW.TWITTER.COM/NWSKEYWEST



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