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000
FXUS62 KMFL 151410
AFDMFL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
910 AM EST FRI FEB 15 2013

.UPDATE...
NO MAJOR CHANGE TO FORECAST EXCEPT TO REFLECT CURRENT CONDITIONS
AND PATH OF SHOWERS ON RADAR IN THE POPS. LOOKING AT CONVECTIVE
POSSIBILITY, NOT THINKING MUCH IN THE WAY OF THUNDERSTORMS AS MOST
OF THE CAPE HAS PUSHED TO THE SOUTH AND ABUNDANT CLOUD COVER OVER
THE FORECAST AREA. HOWEVER, ANY BREAKS IN CLOUDS COULD GIVE RISE
TO AN ISOLATED THUNDERSTORM, SO HAVE NOT REMOVED THEM FROM THE
FORECAST THIS MORNING. OTHERWISE, FORECAST IS ON TRACK.

&&

.PREV DISCUSSION... /ISSUED 632 AM EST FRI FEB 15 2013/

AVIATION...
THERE WILL BE PERIODS OF MVFR AND VFR CONDITIONS THROUGH FRIDAY
AND INTO FRIDAY NIGHT. THE COLD FRONT HAS MOVED OFF TO THE SOUTH
AND SHOWERS WILL REMAIN IN PLACE DURING THE DAY ON FRIDAY AS THE
COLD FRONT HAS STALLED OUT JUST TO THE SOUTH. THERE COULD BE SOME
PERIODS OF IFR ON FRIDAY ESPECIALLY WHEN A SHOWER MOVES OVER THE
TERMINALS. WINDS ARE EXPECTED TO INCREASE TO NEAR 10 KNOTS BY THE
MIDDLE OF FRIDAY MORNING ACROSS ALL TERMINALS. SHOWERS WILL BEGIN
TO DIMINISH DURING THE EVENING HOURS AND VFR CONDITIONS WILL
RETURN BY SATURDAY.

PREV DISCUSSION... /ISSUED 307 AM EST FRI FEB 15 2013/

DISCUSSION...
THE MID LEVEL TROUGH THAT BROUGHT A WEAK FRONTAL BOUNDARY DROOPING
ACROSS SOUTH FLORIDA IS NOW WELL OFF TO THE NORTHEAST WITH A
STRONGER POLAR TROUGH DEEPENING OVER EASTERN NORTH AMERICA. THE
INITIAL FRONTAL BOUNDARY HAS PUSHED THROUGH THE PENINSULA AND HAS
STALLED OVER THE FLORIDA STRAITS. THIS HAS LEFT AN ABUNDANT SUPPLY
OF DEEP MOISTURE ACROSS SOUTH FLORIDA WITH A VERY SHALLOW LOW
LEVEL NORTHEAST FLOW BEHIND THE FRONT AND SOUTHWEST FLOW ABOVE 2K
FEET. THUS, SCATTERED TO NUMEROUS SHOWERS AND POSSIBLY A
THUNDERSTORM WILL CONTINUE TO MOVE ACROSS SOUTH FLORIDA THROUGH
THIS EVENING. WHILE THERE IS THE SLIM POTENTIAL FOR A THUNDERSTORM
TODAY, THE MAIN FOCUS WILL LIKELY BE OFFSHORE IN THE ATLANTIC
WATERS WHERE THE GREATEST INSTABILITY WILL OCCUR NEARER TO THE
SURFACE BOUNDARY. AS THE POLAR TROUGH DEEPENS INTO THE EASTERN
U.S., THE MOISTURE FIELD WILL BEGIN TO BE SHOVED TO THE EAST AND A
SLOW DRYING TREND IS EXPECTED TONIGHT SO THE GREATEST CHANCE FOR A
SHOWER WILL BE DURING THE EVENING HOURS.

THIS SECOND TROUGH WILL THEN BEGIN AN EASTWARD MOVE LATE SATURDAY
AND SUNDAY WITH STRONG CAA TAKING SHAPE ACROSS SOUTH FLORIDA WITH
POSSIBLY THE COLDEST AIR THUS FAR THIS SEASON FOR BOTH SUNDAY
MORNING AND AGAIN MONDAY MORNING. THE CAA ON SATURDAY NIGHT ALONG
WITH A TIGHTENING PRESSURE GRADIENT IN RESPONSE TO A STRENGTHENING
SURFACE HIGH PRESSURE OVER THE SOUTHEAST STATES WILL KEEP A NORTH
WIND ELEVATED. TEMPERATURES BY EARLY SUNDAY MORNING WILL RANGE
FROM THE LOWER AND MID 30S AROUND LAKE OKEECHOBEE TO THE LOWER AND
MID 40S ALONG BOTH COASTS EXCEPT UPPER 40S TO NEAR 50 ALONG THE
IMMEDIATE SOUTHEAST COAST. THIS ALONG WITH A NORTH WIND OF 10 TO
15 MPH WILL CREATE WIND CHILL READINGS IN THE MID TO UPPER 20S
OVER THE INTERIOR AND MID 30S TO AROUND 40 ALONG BOTH COASTS. HIGH
TEMPERATURES SUNDAY AFTERNOON WILL STRUGGLE TO GET INTO THE LOWER
60S. THE SURFACE HIGH WILL BE CENTERED NEAR THE CENTRAL GULF
COAST SUNDAY MORNING AND SHIFT TO SOUTHERN GEORGIA BY MONDAY
MORNING WITH THE GRADIENT RELAXING. SO SUNDAY NIGHT INTO EARLY
MORNING WILL EXPERIENCE MUCH LESS WIND AND MORE OF A RADIATIONAL
COOLING EVENT. TEMPERATURES ON MONDAY MORNING WILL LIKELY AGAIN
REACH NEAR FREEZING OVER THE INTERIOR WEST OF LAKE OKEECHOBEE AND
A COUPLE OF DEGREES WARMER ALONG THE EAST COAST BUT STILL SEVERAL
DEGREES BELOW THE AVERAGE FOR MID FEBRUARY.

SOUTH FLORIDA WILL RETURN TO A ZONAL FLOW PATTERN ON TUESDAY WITH THE
SURFACE RIDGE SHIFTING INTO THE ATLANTIC. THIS WILL BEGIN TO
MODIFY TEMPERATURES THROUGH THE WEEK WITH SEVERAL STORM SYSTEMS
MOVING ALONG THE NORTHERN STATES RETURNING SOUTH FLORIDA TO DRY
CONDITIONS ALONG WITH NEAR NORMAL OR SLIGHTLY ABOVE THE AVERAGE BY
THE END OF THE WEEK.

MARINE...
THERE WILL BE AN ABUNDANCE OF SHOWERS AND POSSIBLY A THUNDERSTORM
OVER THE REGIONAL WATERS THROUGH THIS EVENING WITH MOSTLY LIGHT
WINDS EXCEPT STRONGER NEAR THE SHOWERS AND STORMS. WIND AND SEAS
WILL THEN RAPIDLY DETERIORATE LATE SATURDAY THROUGH SUNDAY AS A
STRONG NORTHWEST TO NORTH WIND DEVELOP WITH SEAS BUILDING TO WELL
OVER 7 FEET IN THE ATLANTIC AND THE OFFSHORE GULF WATERS. WIND AND
SEAS WILL THEN SUBSIDE IN THE EARLY PART OF NEXT WEEK.

FIRE WEATHER...
NO PROBLEMS OR CONCERNS THROUGH TONIGHT WITH HIGH LOW LEVEL
MOISTURE IN PLACE. A MUCH COLDER AND DRIER AIRMASS WILL ARRIVE
LATE SATURDAY INTO MONDAY WITH RELATIVE HUMIDITIES LIKELY FALLING
TO NEAR 35 PERCENT SATURDAY AFTERNOON AND IN THE 20S ACROSS ALL OF
SOUTH FLORIDA SUNDAY AFTERNOON. A SLOW MODIFICATION IS THEN
ANTICIPATED EARLY NEXT WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH  75  58  75  43 / 90 50 20 -
FORT LAUDERDALE  76  61  77  46 / 80 50 20 -
MIAMI            75  61  77  47 / 60 50 20 -
NAPLES           69  58  73  45 / 80 50 20 -

&&

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&

$$

DISCUSSION/MARINE/FIRE...13/SI
AVIATION/RADAR...84/AK