000
FXUS64 KHUN 240151 AAB
AFDHUN

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE HUNTSVILLE AL
851 PM CDT THU MAY 23 2013

.UPDATE...
MADE WHOLESALE CHANGES TO ONGOING FORECAST.

&&

.DISCUSSION...
A SFC COLD FRONT ADVECTING SOUTHWARD, AHEAD OF AN UPPER LOW OVER THE
GREAT LAKES, IS CURRENTLY LOCATED ACROSS THE TN RIVER VALLEY. BEHIND
THE FRONT ADDITIONAL SCT-BKN LOW CLOUDS WILL ADVECT SOUTHWARD FROM
THE OH RIVER VALLEY ALONG WITH DRIER AIR AND COOLER TEMPS OVER THE
NEXT 6-10 HOURS.

HAVE INCORPORATED HIGH END PARTLY CLOUDY CONDITIONS FOR THE ONCOMING
CLOUD COVER WITH THE FRONT. TEMPS ARE NOT COOLING OFF AS QUICKLY AS
ORIGINALLY FORECAST DUE TO WINDS STAYING HIGH ENOUGH TO TEMPER
RADIATIONAL COOLING. THUS, HAVE ADJUSTED OVERNIGHT LOWS BY MAKING
TWEAKS TO GUIDANCE FROM LOCAL WRF MODEL OUTPUT (AND TAKING INTO
ACCOUNT APPROACHING CLOUD COVER FOR LATER TONIGHT). MOST AREAS SHOULD
DROP OFF INTO THE LOW TO MID 50S. IN ADDITION, MADE TREND AND
ADJUSTMENTS TO THE DEWPOINTS AND WIND FORECAST WITH MORE OF A
TERRAIN GRADIENT INCORPORATED FOR WIND SPEEDS (I.E. HIGHER WIND
SPEEDS OVER HIGHER TERRAIN) AS SOMEWHAT HIGHER WINDS ARE PRESENT WITH
CAA FROM A N (LATER TO NE) WIND DIRECTION POST-FROPA. WINDSPEEDS
SHOULD THEN INCREASE AREAWIDE A COUPLE OF HOURS AFTER SUNRISE.

SL.77

&&

.AVIATION...
/ISSUED 621 PM CDT THU MAY 23 2013/
FOR 00Z TAFS...

VFR CONDITIONS AND LIGHTER WINDS ARE EXPECTED TO PREVAIL OVER THE
NEXT 6-7 HOURS WHEN A SFC COLD FRONT CROSSES THE REGION. LOW STRATUS
WILL ACCOMPANY THIS FRONT AND MAY RESULT IN CIGS DROPPING TO `ADDL
FUEL REQ` CONDITIONS BTWN 07-11Z, AND WINDS VEERING TO THE N/NE.
WINDS ARE EXPECTED TO INCREASE AFTER 14Z THROUGH THE REST OF THE
FORECAST PERIOD AS A SFC HIGH PRESSURE SYSTEM ADVECTS SOUTHWARD.

SL.77

&&

.HUN WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
TN...NONE.
&&

$$

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AT WEATHER.GOV/HUNTSVILLE.