Hail and Damaging Winds in Tennessee, July 21 to 22, 2008

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
341 PM CDT MON JUL 21 2008

.DISCUSSION...
DEVELOPING UPPER LOW OVER THE GREAT LAKES WILL ALLOW AN UPPER TROUGH
TO AMPLIFY OVER MUCH OF THE EASTERN THIRD OF THE COUNTRY THROUGH
WEDNESDAY. TROUGH AXIS WILL EXTEND SOUTHWARD ACROSS THE MID STATE
WITH A RATHER ACTIVE NW FLOW ALOFT.

ALREADY SEEN WITH THE ACTIVE FLOW IS A COMPLEX OF STORMS WHICH IS
CURRENTLY MOVING SOUTHWARD ACROSS THE NORTHERN PLATEAU. THIS
ACTIVITY WILL PERSIST AND ENOUGH INSTABILITY IS PRESENT SO AS TO
WARRANT A SVR TSTM WATCH WHICH WILL REMAIN IN EFFECT UNTIL 8 PM
THIS EVENING.

FOR TONIGHT...NW FLOW REMAINS IN TACT BUT OTHER THAN THE CURRENT
CONVECTION IN OUR EASTERN COUNTIES...AREAS WEST OF THE PLATEAU
MAY NOT SEE MUCH IN THE WAY OF CONVECTION. NEVERTHELESS...SOME
WEEK PVA MAY MOVE ACROSS THE AREA TOWARD 12Z. THUS...LOW POPS WILL
BE NEED FOR THE OVERNIGHT. POPS WILL NEED TO BE ELEVATED SOME
ACROSS THE PLATEAU PER THE WATCH AS WELL AS THE LATEST RADAR
TRENDS JUST PRIOR TO 4 PM.

ON TUESDAY...ASSOCIATED FRONTAL BOUNDARY BEGINS TO MAKE SOUTHWARD
PROGRESS AND WILL BE MOVING SOUTH OF THE OH RIVER IN THE AFTERNOON.
BY 00Z...SHOULD SEE SCT ACTIVITY ACROSS NORTHERN AREAS AND ISOL
STORMS FOR THE SOUTH. GOOD INSTABILITY TOMORROW AFTERNOON AND WE
COULD SEE A FEW SEVERE STORMS.

THE BEST CHANCE FOR SHOWERS AND STORMS...HOWEVER...WILL BE TUESDAY
NIGHT AS THE FROPA OCCURS AND THE BETTER UPPER DYNAMICS ARE IN
PLACE. WILL AGAIN INCLUDE THE RISK OF SVR WITH LARGE HAIL AND
DAMAGING WINDS BEING POSSIBLE.

AS FOR THE SHORT TERM TEMPS...WILL AGAIN TAKE THE OVER FOR LOWS
TONIGHT VERSUS THE MAV. THE REMAINING PERIODS LOOK OK.

IN THE EXT FCST...WE GET A BRIEF REPRIEVE FROM RAIN CHANCES ON WED
NT AND THU AS DRIER AND SOMEWHAT COOLER AIR MOVES IN. THIS WILL BE
SHORT LIVED AS MOISTURE INCREASES AND THE NW FLOW BECOMES ACTIVE
AGAIN. WILL INCLUDE 20-30 POPS FOR THU NT THROUGH SUN NT. THE HIGHER
30 POPS WILL BE ON SAT NT AND SUN WHEN A FRONTAL BOUNDARY APPEARS TO
EXERT ITS GREATEST IMPACT ON THE MID STATE.

AS THE TROUGH PULLS FURTHER EAST...HEIGHT RISES WILL AGAIN BE ON
ORDER ALTHOUGH THE UPPER HIGH STAYS TO OUR WEST. THAT ALL EQUATES
TO A RETURN TO HIGH TEMPS IN THE LOWER TO MID 90S AND LOWS IN THE
LOWER 70S.

.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE      74  95  71  86 /  20  30  50  40
CLARKSVILLE    71  92  69  86 /  20  30  50  30
CROSSVILLE     68  89  66  79 /  60  30  50  40
COLUMBIA       73  95  71  86 /  20  20  50  40
LAWRENCEBURG   73  96  72  86 /  20  20  50  40
WAVERLY        72  93  70  86 /  20  30  50  30

&&

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

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HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
328 PM CDT MON JUL 21 2008

TNZ005>011-022>034-056>066-075-077>080-093>095-222030-
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-DEKALB-WHITE-
CUMBERLAND-BEDFORD-COFFEE-WARREN-GRUNDY-VAN BUREN-WAYNE-LAWRENCE-
GILES-
328 PM CDT MON JUL 21 2008

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MIDDLE TENNESSEE.

.DAY ONE...THIS AFTERNOON AND TONIGHT

A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL 8 PM CDT THIS
EVENING FOR AREAS NEAR AND IN THE CUMBERLAND PLATEAU REGION.
STORMS COULD PRODUCE DAMAGING WINDS...DESTRUCTIVE HAIL...AND
DEADLY CLOUD TO GROUND LIGHTNING. THESE STORMS COULD ALSO PRODUCE
RAINFALL AMOUNTS OF 1 TO 2 INCHES. THIS WILL PRODUCE FLOODING OF
LOW LYING AND POOR DRAINAGE AREAS.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

A COLD FRONT WILL PUSH SOUTHWARD...OUT OF THE OHIO VALLEY...INTO
MIDDLE TENNESSEE...TUESDAY NIGHT AND WEDNESDAY. SCATTERED
THUNDERSTORMS WILL DEVELOP ACROSS THE MID STATE...A FEW OF WHICH
COULD BECOME SEVERE...WITH DAMAGING WINDS AND HAIL. HEAVY
DOWNPOURS...AND MINOR LOCALIZED FLOODING...WILL ALSO BE POSSIBLE.

.SPOTTER INFORMATION STATEMENT...

THIS AFTERNOON THROUGH EARLY EVENING SPOTTER AND EMERGENCY
MANAGER ACTIVATION MAY BE NEEDED.

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