Severe Thunderstorm Warning 138, NWS Nashville, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
1054 AM CDT FRI MAY 28 2010

.UPDATE...AS OF 15Z IT WAS MOSTLY CLOUDY-TO-CLOUDY ACROSS THE
MAJORITY OF MIDDLE TENNESSEE, EXCEPT FOR THE NORTHWESTERN
COUNTIES, WHICH REMAINED PARTLY CLOUDY. TEMPERATURES WERE MAINLY
IN THE MIDDLE AND UPPER 70S.

LATEST MODEL GUIDANCE SHOWS DEEP MOISTURE REMAINING ACROSS THE
BULK OF MIDDLE TENNESSEE TODAY, WITH MOST PLACES THAT ARE OVERCAST NOW
EXPECTED TO REMAIN MOSTLY CLOUDY FOR THE REMAINDER OF THE DAY.
HIGH AND MID LEVEL CLOUDS WILL PREDOMINATE. HOWEVER, EVEN IF MID
AND HI CLOUDS THIN SOME, EXPECT SCT-BKN CU TO DEVELOP THIS
AFTERNOON AFTER TEMPERATURES MIGRATE INTO THE LOWER 80S.

LATEST FORECAST 21Z RUC SOUNDING FOR BNA SHOWS LOWER LEVELS
MOISTENING UP DURING THE AFTERNOON AND PW'S AROUND 1.50 INCHES.
TOTALS INDEX GOES TO 49 AND CAPE INCREASES TO 3K J/KG. THUS, ANY
THUNDERSTORMS THAT DEVELOP TODAY CAN BE EXPECTED TO CONTAIN BRIEF
TORRENTIAL DOWNPOURS. IN ADDITION, SOME OF THE STORMS, ESPECIALLY
OVER THE EASTERN HALF OF OUR FORECAST AREA COULD BE SLOW- MOVING.
LATEST FORECAST AFTERNOON RUC SOUNDING FOR CSV AND BNA SHOWS EAST
WINDS OF ONLY 5KTS IN THE 8K-25K FT LAYER. STORMS SHOULD MOVE A LITTLE
FASTER WEST OF I-65, GENERALLY SOUTHWARD AT 10 TO 15 MPH.

WILL PROBABLY MENTION "LOCALLY HEAVY RAINFALL POSSIBLE" FOR THE
EASTERN HALF OF OUR FORECAST AREA, GENERALLY EAST OF I-65.

THE INCREASE IN LOW LEVEL MOISTURE IS EXPECTED TO BE IN RESPONSE
TO 850MB LOW PRESSURE AREA DEVELOPING SOUTHWESTWARD OUT OF
KENTUCKY, AND WILL BE MOST PRONOUNCED OVER OUR NORTHERN AND
EASTERN AREAS BY LATE TODAY.

AFTERNOON POPS LOOK REASONABLE FOR TODAY, BUT HAVE TRIMMED A FEW
DEGREES OFF MAX TEMP EXPECTATIONS IN THE MOSTLY CLOUDY AREAS.

WILL RELEASE UPDATED ZFP SHORTLY.

&&

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

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HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
1127 AM CDT FRI MAY 28 2010

TNZ005>011-022>034-056>066-075-077>080-093>095-291630-
STEWART-MONTGOMERY-ROBERTSON-SUMNER-MACON-CLAY-PICKETT-BENTON-
HOUSTON-HUMPHREYS-DICKSON-CHEATHAM-DAVIDSON-WILSON-TROUSDALE-
SMITH-JACKSON-PUTNAM-OVERTON-FENTRESS-PERRY-HICKMAN-LEWIS-
WILLIAMSON-MAURY-MARSHALL-RUTHERFORD-CANNON-DE KALB-WHITE-
CUMBERLAND-BEDFORD-COFFEE-WARREN-GRUNDY-VAN BUREN-WAYNE-LAWRENCE-
GILES-
1127 AM CDT FRI MAY 28 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MIDDLE TENNESSEE.

.DAY ONE...THIS AFTERNOON AND TONIGHT

SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP OVER MUCH OF THE MID STATE THIS AFTERNOON. A FEW
THUNDERSTORMS COULD BECOME SEVERE WITH DAMAGING WINDS AND LARGE
HAIL. IN ADDITION... STEERING CURRENTS WILL BE RELATIVELY WEAK
OVER THE EASTERN HALF OF THE AREA, WHICH MEANS THUNDERSTORMS WILL
BE SLOW-MOVING AND CAPABLE OF PRODUCING LOCALLY HEAVY RAINFALL...AND
PONDING OF WATER.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY
AN UPPER LEVEL LOW PRESSURE SYSTEM WILL BECOME A MAINSTAY OVER THE
SOUTHEAST STATES SATURDAY INTO MONDAY. MORE SCATTERED AFTERNOON
AND EVENING PULSE THUNDERSTORMS ARE EXPECTED...SOME WITH STRONG
WINDS...HAIL AND LOCALLY HEAVY RAINFALL.

.SPOTTER INFORMATION STATEMENT...

REPORTS FROM TRAINED WEATHER SPOTTERS MAY BE NEEDED THIS AFTERNOON.

SPOTTER THUNDERSTORM REPORTING CRITERIA...
TORNADO
FUNNEL CLOUD
FLOODING
HAIL >= 1/2 INCH
WINDS > 50 MPH (MEASURED)
STRUCTURAL DAMAGE
TREES OR POWER LINES DOWN

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