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000
FXUS64 KOHX 232324
AFDOHX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
624 PM CDT WED JUL 23 2014

.UPDATE...FOR 00Z AVIATION.

&&

.AVIATION...00Z TAF DISCUSSION.

THE COLD FRONT THAT WILL BE THE MAIN CULPRIT IN SCATTERED SHOWERS
AND THUNDERSTORMS THIS EVENING IN MIDDLE TENNESSEE IS STRETCHING
WEST TO EAST ACROSS KY AT ISSUANCE. IN ADDITION TO THE FRONT...
OUTFLOW BOUNDARIES AROUND THE AREA WILL HELP TO SPARK TS ACTIVITY
FOR THE NEXT COUPLE OF HOURS. FLIGHT CATEGORIES REMAIN VFR OUTSIDE
THIS ACTIVITY...BUT SHOULD FALL TO IFR FOR A SHORT PERIOD IF ANY
TERMINAL IS DIRECTLY AFFECTED BY TS.

BY 05Z...TS ACTIVITY SHOULD BE WANING...IF NOT OVER...FOR OUR
TERMINALS. WE WILL THEN HAVE TO FOCUS ON THE FOG DEVELOPMENT AND
TRAILING LOW CIGS THROUGH ABOUT 14-15Z THURSDAY MORNING. IFR TO
MVFR VIS AND CIG WILL LIKELY PLAGUE ALL 3 TERMINALS THROUGH THIS
TIME...BEFORE RETURNING TO VFR BY 18Z THURSDAY.

WINDS THAT ARE CURRENTLY WEST TO NW WILL SHIFT TO THE NORTH AS THE
FRONT MOVES THROUGH TONIGHT. A 10KT NORTHERLY BREEZE WILL BE
COMMON THURSDAY AFTERNOON.

UNGER

&&

.PREV DISCUSSION... /ISSUED 305 PM CDT WED JUL 23 2014/

DISCUSSION...A FRONT ALONG THE OHIO RIVER THIS AFTERNOON WILL
PUSH INTO MID TN WITH AT LEAST SCATTERED THUNDERSTORMS CONTINUING
INTO TONIGHT. THE DYNAMICS AND WIND WITH THIS FRONT ARE FAIRLY
WEAK...AND SHORT RANGE MODELS ARE DEPICTING RATHER SPARSE THUNDERSTORM
COVERAGE THIS EVENING. STILL...WE WILL STICK WITH LIKELY POPS FOR
AREAS AROUND BNA AND EASTWARD SINCE THE FRONT WILL BE ENCOUNTERING
A MODERATELY UNSTABLE ATMOSPHERE WITH PW VALUES NEAR 2 INCHES.
THIS WILL NOT BE A WIDESPREAD BIG RAINFALL PRODUCER...BUT A FEW
SPOTS WILL PICK UP SOME HEAVY DOWNPOURS. POPS WILL TREND DOWNWARD
AFTER DARK...SINCE MUCH OF THE CONVECTION WILL BE HEAT DRIVEN.

ON THURSDAY...WE WILL KEEP SMALL POPS IN THE FORECAST DUE TO THE
SLUGGISH FRONT MOVEMENT AND A SECONDARY MID LEVEL TROUGH PASSAGE.
COOLER AND DRIER AIR WILL BE MOVING IN WITH NORTH WINDS AND HIGHS
MAINLY IN THE LOW TO MID 80S.

THURSDAY NIGHT THROUGH SATURDAY...MID TN WILL BE UNDER THE
INFLUENCE OF HIGH PRESSURE. UPPER HEIGHTS WILL BE ELEVATED ...SO
TEMPERATURES WILL REBOUND QUICKLY. HIGHS WILL BE WELL INTO THE 80S
FRIDAY...AND LOWER 90S SATURDAY. HUMIDITY LEVELS WILL BE PLEASANT
ENOUGH THURSDAY NIGHT...BUT BECOMING STICKY BY LATE SATURDAY.

THE NEXT SYSTEM WILL BRING A CHANCE FOR THUNDERSTORMS BY SUNDAY
WITH A FRONTAL PASSAGE EXPECTED SUNDAY NIGHT. INSTABILITY
PARAMETERS ON SUNDAY AFTERNOON ARE RATHER IMPRESSIVE SO STRONG
STORMS WITH SOME HEAVY DOWNPOURS LOOKS POSSIBLE.

A FAIRLY POTENT SURFACE HIGH FOR LATE JULY WILL THEN BUILD IN
FROM THE NORTH. THERMAL TROUGHING LOOKS IMPRESSIVE WITH 850 MB
TEMPS DOWN TO 10 DEG C. HIGHS IN THE LOWER TO MID 80S WITH LOW
RELATIVE HUMIDITY ARE EXPECTED MONDAY THROUGH WEDNESDAY.

13

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

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