Severe Thunderstorm Warning 363, NWS Nashville, TN

516 
WWUS54 KOHX 041059
SVSOHX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
559 AM CDT THU AUG 4 2011

TNC099-181-041115-
/O.CON.KOHX.SV.W.0363.000000T0000Z-110804T1115Z/
WAYNE TN-LAWRENCE TN-
559 AM CDT THU AUG 4 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTHWESTERN
LAWRENCE AND SOUTHERN WAYNE COUNTIES UNTIL 615 AM CDT...

AT 557 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF
60 MPH.  THIS STORM WAS LOCATED 8 MILES SOUTH OF COLLINWOOD...OR 18
MILES SOUTH OF WAYNESBORO...MOVING SOUTH AT 30 MPH.

LOCATIONS IMPACTED INCLUDE...
  IRON CITY AND ST. JOSEPH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MILES PER
HOUR...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. FOR
YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR
HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE
INTO AREAS WHERE WATER COVERS THE ROAD.

&&

LAT...LON 3500 8798 3501 8799 3515 8799 3516 8750
      3500 8747
TIME...MOT...LOC 1059Z 340DEG 21KT 3506 8779

$$

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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
459 AM CDT THU AUG 4 2011

.AVIATION 12Z DISCUSSION...
FRONTAL BOUNDARY TO SLIP SOUTH OF THE TAF AREAS TODAY.
THUS...DRIER CONDITIONS TO PREVAIL. NW FLOW ALOFT WILL CONTINUE
HOWEVER...BUT THE NEXT DISTURBANCE WILL NOT EFFECT THE AREA UNTIL
AFTER THE 24 HR TAF WINDOW.

OTW...WE WILL SEE GENERALLY VFR VSBYS FROM 08Z TO 12Z.

&&

.PREV DISCUSSION... /ISSUED 352 AM CDT THU AUG 4 2011/

DISCUSSION...
ANALYSIS SHOWING FRONTAL BOUNDARY DROPPING DOWN TOWARD THE TN/KY
BORDER...WITH PRE-FRONTAL TROUGH/OUTFLOW DOWN INTO NORTH AL. UPPER
RIDGES CONTINUE TO SLOWLY WEAKEN/RETROGRADE...WHICH IS CURRENTLY
BRINGING PRETTY GOOD IMPULSE DOWN ACROSS THE CWA. AIRMASS REMAINS
WARM/UNSTABLE...WITH STORMS CONTINUING TO FIRE TOWARD TN RIVER.

FRONTAL BOUNDARY EXPECTED TO DRIFT FURTHER SOUTH TODAY...SETTING
UP NEAR THE TN/AL BORDER DURING THE AFTERNOON. THIS BOUNDARY EXPECTED
TO MEANDER IN THAT GENERAL VICINITY TONIGHT AND AGAIN ON FRIDAY.
A BIT OF MEAN DRYING EXPECTED TO OCCUR NORTH TODAY...LEAVING MOST
ADDITIONAL DEVELOPMENT ACROSS THE SOUTH. TEMPS AGAIN EXPECTED IN
THE MID/UP 90S MOST OF AREA...BUT DEWPTS EXPECTED TO STAY IN THE
70S SOUTH/SOUTHWEST...WHICH WILL AGAIN BRING HEAT INDEX VALUES
THERE TO AROUND 105.

MOST OF THE AREA WILL REMAIN DRY TONIGHT WITH ONLY ISOLATED STORMS
EXPECTED BUT THINGS WILL AGAIN BECOME MORE ACTIVE ON FRIDAY...ESPECIALLY
WEST. AIRMASS MOISTENS UP AND PASSING UPPER WAVE STEEPENS LAPSE
RATES SUCH THAT COMBINED WITH WEAKENING SFC/LL BOUNDARY...ISOLATED
SEVERE THUNDERSTORMS NOT OUT OF QUESTION IN THE AFTERNOON. SFC/LL
BOUNDARY MORELESS WASHES OUT FRIDAY NIGHT AS STATION FRONT SETS UP
ACROSS THE OH VALLEY. ISO STORMS WEST TO SCT STORMS EAST WILL
CONTINUE AS THIS OCCURS.

SATURDAY WILL BE THE BEGINNING OF A SEVERAL DAY TRANSITION THAT WILL
SEE ML/UL HIGHS OVER TX REGION MIGRATE SLOWLY WEST...SETTING UP
OVER THE DESERT SOUTHWEST BY EARLY MONDAY...AND REMAINING THERE
THROUGH MOST OF THE UPCOMING WEEK. THIS WILL RESULT IN A PERSISTENT
TROUGH OVER THE EASTERN US. THIS MORE PROGRESSIVE FLOW WILL BRING
A SERIES OF SHORTWAVES/POOL OF MOISTURE ACROSS THE MID-SOUTH
FREQUENTLY. THIS WILL KEEP TEMPS A LITTLE COOLER THAN THEY HAVE
BEEN AS WELL AS LEAVE THE ISO-SCT STORMS IN THE FOLD THROUGHOUT.

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR TNZ022-024-056>058-
060-061-075-077-093>095.

&&

21

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
543 AM CDT WED AUG 3 2011

TNZ005>011-022>034-056>066-075-077>080-093>095-041030-
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-
543 AM CDT WED AUG 3 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MIDDLE TENNESSEE.

.DAY ONE...TODAY AND TONIGHT...

HEAT ADVISORY IS IN EFFECT FOR LOCATIONS WEST OF THE CUMBERLAND
PLATEAU THIS AFTERNOON AND TONIGHT. HOT TEMPERATURES AND HUMIDITY
WILL DRIVE AFTERNOON HEAT INDICES INTO THE 105 TO 110 DEGREE RANGE.

THERE IS ALSO A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
AND EVENING. DAMAGING WIND IS THE MAIN THREAT.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY...

HEAT ADVISORY IS ALSO IN EFFECT FOR LOCATIONS WEST OF THE
CUMBERLAND PLATEAU THURSDAY. TEMPERATURES AND HUMIDITY WILL
PUSH AFTERNOON HEAT INDICES TO AROUND 105 DEGREES.

.SPOTTER CALL TO ACTION STATEMENT...

REPORTS FROM TRAINED WEATHER SPOTTERS MAY BE NEEDED.

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

07

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
516 AM CDT THU AUG 4 2011

TNZ093-041045-
WAYNE-
516 AM CDT THU AUG 4 2011

...SIGNIFICANT WEATHER ADVISORY FOR WAYNE COUNTY...

AT 511 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM 9 MILES NORTHEAST OF OLIVE HILL...OR 9 MILES WEST
OF WAYNESBORO...MOVING SOUTHEAST AT 35 MPH.

THIS STORM WILL BE...
  6 MILES SOUTHWEST OF WAYNESBORO BY 525 AM CDT.
  COLLINWOOD BY 535 AM CDT.

PENNY SIZE HAIL IS EXPECTED WITH THIS STORM.

LAT...LON 3504 8799 3529 8799 3530 8802 3534 8803
      3535 8801 3537 8803 3539 8803 3540 8798
      3542 8798 3547 8771 3528 8760 3505 8759

21