Severe Thunderstorm Warning 273, NWS Nashville, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
255 PM CDT TUE AUG 3 2010

.DISCUSSION...
THE HEATS ON. HAVE UPDATED HEAT ADVISORY WHICH RUNS THROUGH 7 PM
CDT THURSDAY AND ALSO JUST MOMENTS AGO ISSUED AN SPS WHICH
MENTIONS A FEW HEAT SAFETY TIPS. EXCESSIVE HEAT WARNING FOR THE
FAR WESTERN AREAS OF THE MID STATE NOT OUT OF THE QUESTION FOR
WEDNESDAY.

ITS BEEN 3 YEARS SINCE WE HAD TRIPLE DIGIT TEMPS HERE IN MIDDLE
TENNESSEE. THE LAST TIME NASHVILLE WAS IN THE TRIPLE DIGITS WAS
BACK ON AUGUST 24TH 2007 WHEN THE THERMOMETER HIT 102 DEGREES.

ISOLATED DIURNALLY DRIVEN THUNDERSTORMS HAVE FIRED IN THE
AFTERNOON HEAT OVER SOUTHWEST MIDDLE TN AND ALONG THE TN RIVER IN AN
AREA OF DEWPOINT POOLING. ALSO...700 MB TEMPS AT +12.6 CELSIUS SO
WE HAVE A GOOD CAP OVER THE AREA BUT A FEW STORMS HAVE MANAGED TO
BREAK THE CAP IN THE AFTERNOON HEAT. WILL WATCH RADAR TRENDS AND
MAKE FINAL TWEAKS TO FIRST PERIOD FORECAST BEFORE 345 PM CDT.
CIRRUS DEBRIS STILL SINKING SOUTH FROM LEFT OVER MCS THAT PASSED
WELL TO OUR NORTH. DEWPOINTS HAVE LOWERED A FEW DEGREES ACROSS
MUCH OF MIDDLE TN THIS AFTERNOON. THIS HAS HELPED TO HOLD HEAT
INDICIES DOWN IN THE 105 TO 110 RANGE.

DOME OF HIGH PRESSURE WILL REMAIN OVER THE MID STATE THROUGH
THURSDAY BEFORE BEGINNING TO RETROGRADE ALLOWING A WEAK FRONTAL
SYSTEM TO APPROACH FROM THE NORTH BRINGING AN INCREASE IN
THUNDERSTORM ACTIVITY WHICH WILL BREAK THE HEAT TEMPORARILY...BUT
IT WILL BE A SHORT REPRIEVE AS TEMPERATURES WILL HEAT BACK UP INTO
THE UPPER 90S BY THE FIRST OF NEXT WEEK AS THE UPPER LEVEL HIGH
BUILDS OVER THE REGION ONCE AGAIN.

&&

.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE      77 100  77  98 /  10  20  20  20
CLARKSVILLE    76 101  75  99 /  10  10  20  20
CROSSVILLE     70  95  71  92 /  10  20  20  30
COLUMBIA       77 101  76  98 /  10  20  20  20
LAWRENCEBURG   75 100  75  98 /  10  10  20  20
WAVERLY        76 101  75  99 /  10  10  20  20

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 7 PM CDT THURSDAY FOR TNZ005>011-022>033-
056>065-075-077-078-093>095.

&&

BOYD

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
515 AM CDT TUE AUG 3 2010

TNZ005>011-022>034-056>066-075-077>080-093>095-041015-
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-
515 AM CDT TUE AUG 3 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF MIDDLE
TENNESSEE.

.DAY ONE...TODAY AND TONIGHT

DANGEROUSLY HOT CONDITIONS WILL OCCUR ACROSS THE AREA. A HEAT
ADVISORY IS IN EFFECT FOR LOCATIONS WEST OF THE CUMBERLAND
PLATEAU...WHERE HEAT INDEX VALUES MAY EXCEED 105.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THE HEAT WAVE WILL CONTINUE. A HEAT ADVISORY IS IN EFFECT FOR MOST
OF MID TENNESSEE THROUGH THURSDAY. SOME SLIGHT RELIEF FROM THE
HEAT WILL OCCUR FRIDAY AND SATURDAY...BUT TEMPERATURES WILL CLIMB
AGAIN EARLY NEXT WEEK...AND MORE ADVISORIES MAY BE NEEDED.

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SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
214 PM CDT TUE AUG 3 2010

TNZ005>011-022>034-056>066-075-077>080-093>095-040230-
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-
INCLUDING THE CITIES OF...DOVER...CLARKSVILLE...SPRINGFIELD...
GALLATIN...LAFAYETTE...CELINA...BYRDSTOWN...CAMDEN...ERIN...
WAVERLY...DICKSON...ASHLAND CITY...NASHVILLE...LEBANON...
MOUNT JULIET...HARTSVILLE...CARTHAGE...GAINESBORO...COOKEVILLE...
LIVINGSTON...JAMESTOWN...LOBELVILLE...CENTERVILLE...HOHENWALD...
FRANKLIN...BRENTWOOD...COLUMBIA...LEWISBURG...MURFREESBORO...
WOODBURY...SMITHVILLE...SPARTA...CROSSVILLE...SHELBYVILLE...
TULLAHOMA...MANCHESTER...MCMINNVILLE...ALTAMONT...SPENCER...
WAYNESBORO...LAWRENCEBURG...PULASKI
214 PM CDT TUE AUG 3 2010

...HEAT ADVISORY FOR MOST OF MIDDLE TENNESSEE UNTIL 7 PM THURSDAY...

MIDDLE TENNESSEE IS IN THE GRIPS OF THE WORSE HEAT WAVE SINCE
AUGUST 2007. THE DANGEROUS HEAT AND HUMIDITY IS EXPECTED TO LAST
THROUGH THURSDAY AS A LARGE DOME OF HIGH PRESSURE REMAINS OVER THE
AREA. TEMPERATURES ARE EXPECTED TO APPROACH TRIPLE DIGITS THIS
AFTERNOON...GENERALLY WEST OF INTERSTATE 65 AND REACH TRIPLE
DIGITS ACROSS THE WESTERN TWO THIRDS OF THE MID STATE ON WEDNESDAY.
AFTERNOON HEAT INDICIES WILL RANGE FROM 105 TO 110 DEGREES THROUGH
THURSDAY. BY FRIDAY...A WEAK FRONTAL SYSTEM WILL APPROACH THE MID
STATE FROM THE NORTH BRINGING AN INCREASE IN THUNDERSTORM ACTIVITY
WHICH WILL BREAK THE HEAT TEMPORARILY...BUT IT WILL BE A SHORT REPRIEVE
AS TEMPERATURES HEAT BACK UP THE FIRST OF NEXT WEEK.

 ...HEAT WAVE SAFETY TIPS...

IF YOU HAVE TO BE OUTDOORS...

...SLOW DOWN.
...REDUCE OR ELIMINATE STRENUOUS ACTIVITIES.
...IF POSSIBLE...CONFINE OUTDOOR ACTIVITIES TO THE COOLEST PART OF
THE DAY.
...DRESS FOR SUMMER.
...DO NOT DRINK ALCOHOLIC BEVERAGES.
...DONT GET TOO MUCH SUN.
...IF POSSIBLE STAY INDOORS IN AN AIR CONDITIONED PLACE...ESPECIALLY
DURING THE HOTTEST PART OF THE DAY.

BOYD

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
422 PM CDT TUE AUG 3 2010

TNZ023-024-032145-
HOUSTON-HUMPHREYS-
422 PM CDT TUE AUG 3 2010

...SIGNIFICANT WEATHER ADVISORY FOR HOUSTON AND HUMPHREYS COUNTIES...

AT 421 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM NEAR TENNESSEE RIDGE...OR NEAR ERIN...MOVING
SOUTH AT 15 MPH.

WINDS AROUND 50 MPH ARE EXPECTED WITH THIS STORM...ALONG WITH BRIEF
HEAVY RAINFALL...AND FREQUENT CLOUD TO GROUND LIGHTNING.

31