AFDKEY AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS NATIONAL WEATHER SERVICE KEY WEST FL 1126 AM EDT SAT JUL 30 2011 .DISCUSSION... MORNING SURFACE ANALYSIS DEPICTS ATLANTIC SURFACE RIDGING (1020 MILLIBARS) EXTENDING ACROSS NORTH FLORIDA. ALOFT...DEEP-LAYERED RIDGING EXTENDS ACROSS THE SOUTHEASTERN UNITED STATES. THE POSITION OF THIS RIDGING TO OUR NORTH CONTINUES TO BE REFLECTED ON THE KEY WEST AND MIAMI SOUNDINGS...WHICH DISPLAY A MODERATE TO FRESH EASTERLY WIND PROFILE THROUGH 15000 FEET...WITH STRONGER SPEEDS FOUND ABOVE 600 MILLIBARS. HOWEVER...OUR LOCAL SURFACE PRESSURE GRADIENT HAS WEAKENED SOMEWHAT...AND WIND SPEEDS HAVE DIMINISHED SLIGHTLY WHEN COMPARED TO 24 HOURS AGO. AT 15Z...SKIES ACROSS THE ISLAND CHAIN WERE PARTLY TO MOSTLY SUNNY. TEMPERATURES WERE APPROACHING 90 DEGREES...WITH DEWPOINTS IN THE MIDDLE 70S. WINDS AT ISLAND LOCATIONS WERE EASTERLY AT 10 TO 15 MPH. ON THE COASTAL WATERS...WINDS AT 15Z WERE UNIFORMLY EASTERLY NEAR 15 KNOTS. HOURLY PEAK GUSTS AT THE ELEVATED C-MAN STATIONS ALONG THE REEF HAVE NOT EXCEEDED 20 KNOTS SINCE 12Z. KBYX RADAR DETECTS ONLY ISOLATED SHOWERS DOTTING THE FLORIDA STRAITS AS WELL AS THE NEARSHORE AND OFFSHORE GULF WATERS. MOVEMENT OF THIS ACTIVITY IS WESTWARD AT 15 TO 20 KNOTS. THE MORNING SOUNDINGS DISPLAY LITTLE OVERALL CHANGE FROM THE PAST SEVERAL DAYS. A SEASONABLY MOIST AND UNSTABLE ATMOSPHERIC LOWER TROPOSPHERIC PROFILE PERSISTS ACROSS OUR REGION...WHICH SHOULD CONTINUE TO PROMOTE SCATTERED AND GENERALLY LOW-TOPPED SHOWER DEVELOPMENT OVER THE COASTAL WATERS THAT WILL OCCASIONALLY CROSS THE ISLAND CHAIN. A THUNDERSTORM OR TWO MAY DEVELOP LATER THIS AFTERNOON AND EVENING. THE ONLY CHANGE THAT WAS MADE TO THE GRIDS WAS TO LOWER WIND SPEEDS SLIGHTLY THROUGHOUT THE ISLAND CHAIN AND THE COASTAL WATERS. OTHERWISE...PRIOR PHILOSOPHY REMAINS ON TRACK AND NO OTHER SIGNIFICANT CHANGES WERE MADE FROM THE OVERNIGHT FORECASTS. && .MARINE... MODERATE TO OCCASIONALLY FRESH BREEZES WILL PERSIST THROUGHOUT THE KEYS COASTAL WATERS THROUGH THE PREDAWN HOURS ON SUNDAY. SEAS WILL BE SLOW TO SUBSIDE TODAY IN THE FLORIDA STRAITS...AND WE THEREFORE LEFT A CAUTION HEADLINE FOR SEAS UP TO 6 FEET (HIGHER IN THE GULF STREAM) FOR THE ZONES SOUTH OF HAWK CHANNEL. A SLIGHT WIND SURGE THIS EVENING WOULD BRING WINDS BACK INTO THE CAUTION RANGE...AND THIS WILL BE EVALUATED FOR THE AFTERNOON FORECAST PACKAGE. FOR NOW...WE WILL INDICATE WINDS NEAR 15 KNOTS AND GUSTY TONIGHT FOR ALL OF THE KEYS COASTAL WATERS. ATLANTIC RIDGING EXTENDING ACROSS NORTH FLORIDA SINKS SOUTHWARD AND WEAKENS BEGINNING ON SUNDAY. THIS EVOLUTION IN THE SURFACE PRESSURE PATTERN WILL PROMOTE A GENTLE TO MODERATE EAST TO SOUTHEAST WIND REGIME BEGINNING BY LATE SUNDAY AND CONTINUING DURING A MAJORITY OF THE NEXT WEEK. CAUTION OR ADVISORY HEADLINES ARE NOT ANTICIPATED DURING THIS TIME PERIOD. && .AVIATION... VFR WILL PREVAIL KEY WEST AND MARATHON ISLAND TERMINALS THROUGH THE PERIOD...A BRIEF SHOWER REDUCE CIG/VIS TO MVFR. EASTERLY BREEZES WILL PERSIST THROUGH THE PERIOD AND OCCASIONALLY GUST TO 20 KNOTS AFTER 17Z. && .CLIMATE... SINCE FEBRUARY 1ST...ONLY 3.78 INCHES OF RAINFALL HAS BEEN MEASURED AT THE KEY WEST INTERNATIONAL AIRPORT. THIS IS THE DRIEST SUCH STRETCH ON RECORD AT KEY WEST. THE PRIOR DRIEST FEBRUARY 1ST THROUGH JULY 29TH AT KEY WEST OCCURRED IN 1927...WHEN 4.52 INCHES FELL DURING THIS 179-DAY SPAN. RAINFALL RECORDS AT KEY WEST DATE BACK TO 1871. SINCE FEBRUARY 1ST...6.43 INCHES OF RAINFALL HAS BEEN MEASURED AT THE FLORIDA KEYS MARATHON AIRPORT. THIS IS THE DRIEST SUCH STRETCH AT MARATHON SINCE RAINFALL RECORDS HAVE BEEN KEPT FOR THE MIDDLE KEYS. THE PRIOR DRIEST FEBRUARY 1ST THROUGH JULY 29TH AT MARATHON OCCURRED IN 2008...WHEN 8.03 INCHES FELL DURING THIS 179-DAY SPAN. RAINFALL RECORDS FOR THE MIDDLE KEYS ONLY DATE BACK TO 1982. && .KEY WATCHES/WARNINGS/ADVISORIES... FL...NONE. GM...NONE. && $$