Special Weather Statement, NWS Nashville, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
353 AM CDT TUE JUL 23 2013

.DISCUSSION...

AFTER FEELING GOOD FOR THE LAST FEW DAYS REGARDING THE FORECAST
THROUGH THIS UPCOMING WEEKEND...CONFIDENCE HAS WANED AS MODELS
SOLUTIONS HAVE DIVERGED SIGNIFICANTLY...ESPECIALLY FOR FRIDAY AND
SATURDAY.  LET'S START WITH TODAY AND TOMORROW AND WHAT WE CAN
EXPECT AS FAR AS THUNDERSTORM DEVELOPMENT.

DEW POINTS IN THE UPPER 60S AND LOW 70S ARE PREVALENT FROM OKLAHOMA
TO INDIANA AND SOUTHWARD.  THIS EXPANSIVE LOW LEVEL MOISTURE...
COUPLED WITH MULTIPLE SHORTWAVE IMPULSES RIDING THE NORTHWEST FLOW
IN PLACE IS HELPING TO SPARK SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS ACROSS THE MID-MISSISSIPPI AND TENNESSEE VALLEYS.
NONE OF THESE ARE VERY ORGANIZED DUE TO AN EXTREME LACK OF DEEP
LAYER SHEAR.  THIS PATTERN WILL BE THE CONTRIBUTING FACTOR TO
THUNDERSTORM DEVELOPMENT THROUGHOUT THE DAY...BUT A DESTABILIZING
BOUNDARY LAYER DUE TO DIURNAL HEATING SHOULD ALSO ADD TO
THUNDERSTORM COVERAGE. THE BEST CHANCE OF SOME STRONG TO SEVERE
STORMS WILL BE NORTHWEST OF MIDDLE TENNESSEE AS THIS AREA WILL
ALSO BE UNDER THE INFLUENCE OF A WEAK BOUNDARY/FRONT STRETCHING
FROM THE CENTRAL PLAINS INTO THE GREAT LAKES REGION. AS THIS FRONT
SLOWLY PUSHES SOUTHWARD THROUGH THE DAY...IT COULD PUSH A SMALL
CHANCE OF STRONGER STORMS TOWARDS MIDDLE TENNESSEE LATE TODAY...
MAYBE INTO THE EVENING HOURS ACROSS OUR NORTHERN COUNTIES. THE
DECIDING FACTOR IN HOW STRONG THESE STORMS MAY GET WILL BE THE
AMOUNT OF SUNSHINE ANY PARTICULAR AREA RECEIVES TODAY. WILL
HIGHLIGHT THIS SMALL CHANCE IN THE HAZARDOUS WEATHER OUTLOOK...BUT
NOT CONFIDENT IN ANY WIDESPREAD SEVERE STORMS. WEDNESDAY COULD BE
MORE OF THE SAME AS THE FRONT CLOSES IN ON TENNESSEE.

EXPECTATIONS ARE FOR THE FRONT/BOUNDARY TO PUSH THROUGH THE STATE
WEDNESDAY EVENING AND WHILE THERE WILL BE INCREASED CHANCE FOR
SUB-SEVERE SHOWERS AND THUNDERSTORMS...MUCH DRIER AIR WILL FOLLOW
FRONTAL PASSAGE.  IN FACT...THURSDAY WILL DEFINITELY BE PRECIP-FREE
WITH DEW POINTS IN THE LOW 60S...A MUCH WELCOMED CHANGE FROM THE
LAST WEEK.

CONFIDENCE FALLS OFF GREATLY FRIDAY INTO SATURDAY. SOME SORT OF
DECENT SHORTWAVE IS EXPECTED TO MOVE OUT OF THE PLAINS AND INTO
SOME AREA EAST OF THE MISSISSIPPI RIVER BUT ITS PATH IS WHAT HAS
GUIDANCE STUMPED. BECAUSE OF THIS...I AM NOT GOING SWAY FAR FROM
WHAT WE CURRENT HAVE FORECASTED...BOTH TEMPERATURE AND POP-WISE...
IN HOPES OF SOME BETTER RESEMBLANCE OF AGREEMENT BETWEEN LONG
RANGE MODELS IN FUTURE FORECAST PACKAGES.

OBVIOUSLY THIS MODEL DIVERGENCE APPLIES TO TEMPERATURES AS
WELL...ESPECIALLY AFTER FRIDAY...SO WILL ALSO HOLD FIRM ON CURRENT
TEMPERATURES FORECAST FOR THE UPCOMING WEEKEND.

UNGER

&&

.AVIATION...06Z TAF DISCUSSION.

DRIER AIR IN THE MID TO UPPER LEVELS TO PREVAIL AND LIMIT
CONVECTION COVERAGE UNTIL 18Z. AFT 18Z...A COLD FRONT WILL MOVE
TOWARD THE MID STATE AND CONVECTION COVERAGE SHOULD INCREASE TO
THE PROB30 LEVEL. OTW...PLENTY OF LOWER LEVEL MOISTURE IN PLACE
AND THAT WILL LEAD TO A CONTINUATION OF LOW LEVEL STRATUS THROUGH
12Z OVERNIGHT. ADDITIONALLY...SOME LIGHT FOG WILL ALSO BE POSSIBLE
LATE TONIGHT.

&&

.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE      91  72  86  64 /  40  30  30  10
CLARKSVILLE    91  69  84  61 /  40  30  30  05
CROSSVILLE     84  68  82  61 /  40  30  30  20
COLUMBIA       90  72  88  65 /  40  30  40  10
LAWRENCEBURG   89  72  89  66 /  40  30  50  10
WAVERLY        92  70  86  63 /  40  30  40  05

&&

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

&&

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HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
253 AM CDT TUE JUL 23 2013

TNZ005>011-022>034-056>066-075-077>080-093>095-240800-
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-
253 AM CDT TUE JUL 23 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MIDDLE TENNESSEE.

.DAY ONE...TODAY AND TONIGHT.

SCATTERED THUNDERSTORMS ARE EXPECTED TODAY AND TONIGHT. A FEW
STORMS COULD BE STRONG...WITH GUSTY WINDS AND HEAVY DOWNPOURS...
ESPECIALLY THIS AFTERNOON AND EVENING. STRONG WIND GUSTS MIGHT BREAK
TREE BRANCHES...AND HEAVY DOWNPOURS MAY CAUSE TEMPORARY PONDING OF
WATER IN LOW LYING AREAS.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

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SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
421 AM CDT TUE JUL 23 2013

TNZ095-230945-
GILES-
421 AM CDT TUE JUL 23 2013

...SIGNIFICANT WEATHER ADVISORY FOR GILES COUNTY...

AT 416 AM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING
A COUPLE STRONG THUNDERSTORM NEAR PULASKI...MOVING EAST SOUTHEAST
AT 25 MPH.

SOME LOCATIONS IN THE PATH INCLUDE FRANKEWING AND ELKTON...AND AREAS
BETWEEN HIGHWAY 64 AND HIGHWAY 31.

BRIEF WIND GUSTS AROUND 40 MPH ARE EXPECTED WITH THIS STORM...ALONG
WITH HEAVY DOWNPOURS.

LAT...LON 3512 8706 3525 8701 3522 8683 3503 8684

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