Flash Flood Warning 27, NWS Nashville, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
308 PM CDT THU JUN 24 2010

.DISCUSSION...SCATTERED THUNDERSTORMS WERE OCCURRING EAST OF
I 65...AND A BROKEN BAND OF STORMS WAS COMING DOWN ACROSS WEST KY
TOWARD THE MID STATE. THESE WERE OCCURRING JUST AHEAD OF A COLD
FRONT THAT WILL MOVE INTO THE MID STATE LATE AFTERNOON INTO TONIGHT.
HOT AND HUMID AIR WILL CONTRIBUTE TO UNSTABLE CONDITIONS AS THE
FRONT ARRIVES. POPS ARE IN THE LIKELY CATEGORY ACROSS NORTH AND
EAST FOR THE REST OF TODAY. POPS WILL DIMINISH TO "SCATTERED" IN
THE EVENING...THEN SLIGHT CHANCE LATE TONIGHT AS HEATING IS LOST.
THE STORMS WILL LIKELY PRODUCE HEAVY DOWNPOURS AND FREQUENT
LIGHTNING. A FEW WILL PRODUCE DOWNBURST WINDS.

FOR THIS WEEKEND...THE FRONT WILL STALL OVER MID TN...THEN WASH
OUT. THE DISSIPATING FRONT WILL CONTINUE TO SERVE AS A FOCUS FOR
SCATTERED SHOWERS AND STORMS...MAINLY DURING THE AFTERNOON AND
EVENING EACH DAY THROUGH THE WEEKEND. THE DEEPEST MOISTURE AND
HIGHER POPS WILL BE SUPPRESSED SOUTHWARD TO OUR SOUTHERN COUNTIES
FOR FRIDAY...THEN GRADUALLY CREEP NORTHWARD AGAIN.
OTHERWISE...THERE WILL BE LITTLE EFFECT FROM THE "COLD" FRONT. IN
FACT...THE UPPER RIDGE WILL PUMP UP OVER THE WEEKEND...KEEPING OUR
WEATHER HOT AND HUMID.

A BIG CHANGE WILL FINALLY OCCUR EARLY NEXT WEEK. THE UPPER RIDGE
WILL SET UP FARTHER TO THE WEST...ALLOWING UPPER LEVEL WINDS TO
BECOME NNW INTO THE TN VALLEY. A FRONT ACCOMPANIED BY NUMEROUS
SHOWERS AND STORMS WILL ARRIVE ON OR AROUND MONDAY...FOLLOWED BY
SIGNIFICANTLY COOLER AND DRIER AIR. BY MIDWEEK...WE EXPECT CLEAR
SKIES WITH HIGHS IN THE 80S AND LOWS IN THE 60S...WITH MUCH MORE
COMFORTABLE HUMIDITY LEVELS. THE GFS MAY BE A LITTLE TOO DRAMATIC
WITH THIS PATTERN...AS THE ECMWF KEEP HIGHER HEIGHTS. WE WILL
INITIALIZE WITH GFS DATA...THEN ADJUST TEMPS TO BE A LITTLE
WARMER...AND HANG ONTO SMALL POPS A LITTLE LONGER THAN GFS MOS.

&&

.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE      72  91  73  94 /  50  30  10  20
CLARKSVILLE    69  91  70  94 /  30  20  10  20
CROSSVILLE     67  86  66  89 /  40  30  20  20
COLUMBIA       73  92  73  95 /  50  30  20  30
LAWRENCEBURG   72  92  72  95 /  50  40  20  30
WAVERLY        70  92  71  95 /  50  30  10  20

&&

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

&&

13

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
906 AM CDT THU JUN 24 2010

TNZ005>011-022>034-056>066-075-077>080-093>095-251415-
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-
906 AM CDT THU JUN 24 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MIDDLE TENNESSEE.

.DAY ONE...TODAY AND TONIGHT

AN APPROACHING COLD FRONT WILL CAUSE SCATTERED THUNDERSTORMS TO
DEVELOP. SOME OF THE STORMS COULD BE STRONG...OR VERY BRIEFLY
SEVERE...THIS AFTERNOON AND EVENING. LOCALLY HEAVY DOWNPOURS AND
FREQUENT LIGHTNING WILL OCCUR...AND A FEW STORMS MAY PRODUCE BRIEF
GUSTY WINDS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

EVEN THOUGH ANY SEVERE THUNDERSTORMS ARE EXPECTED TO BE BRIEF AND
ISOLATED, SPOTTERS ARE ENCOURAGED TO CLOSELY MONITOR WEATHER
CONDITIONS AND BE PREPARED TO CALL IN ANYTHING REACHING REPORTING
CRITERIA.

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

13

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
159 PM CDT THU JUN 24 2010

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0135 PM     TSTM WND DMG     MCMINNVILLE             35.69N 85.78W
06/24/2010                   WARREN             TN   LAW ENFORCEMENT

            ONE LARGE TREE WAS DOWNED AND WAS BLOCKING PETTIGAP ROAD.

&&

31

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
337 PM CDT THU JUN 24 2010

TNZ006-007-242130-
MONTGOMERY-ROBERTSON-
337 PM CDT THU JUN 24 2010

...SIGNIFICANT WEATHER ADVISORY FOR MONTGOMERY AND ROBERTSON
COUNTIES...

AT 336 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM 7 MILES NORTHEAST OF CLARKSVILLE...MOVING
EAST AT 20 MPH.

THIS STORM WILL BE NEAR...
  GUTHRIE BY 345 PM CDT.

WINDS 40 TO 50 MPH ARE EXPECTED WITH THIS STORM....ALONG WITH
FREQUENT CLOUD TO GROUND LIGHTNING...AND BRIEF HEAVY DOWNPOURS THAT
COULD MAKE DRIVING ON AREA ROADS DIFFICULT. EXERCISE CAUTION WHILE
DRIVING ON AREA ROADWAYS.

31

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
426 PM CDT THU JUN 24 2010

TNZ005-006-008-010-011-022>034-064-242200-
BENTON-CHEATHAM-CLAY-DAVIDSON-DEKALB-DICKSON-FENTRESS-HOUSTON-
HUMPHREYS-JACKSON-MONTGOMERY-OVERTON-PICKETT-PUTNAM-SMITH-STEWART-
SUMNER-TROUSDALE-WILSON-
426 PM CDT THU JUN 24 2010

...SIGNIFICANT WEATHER ADVISORY FOR BENTON...CHEATHAM...CLAY...
DAVIDSON...DEKALB...DICKSON...FENTRESS...HOUSTON...HUMPHREYS...
JACKSON...MONTGOMERY...OVERTON...PICKETT...PUTNAM...SMITH...
STEWART...SUMNER...TROUSDALE AND WILSON COUNTIES...

AT 415 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS
INDICATING AN OUTFLOW BOUNDARY...OR GUST FRONT MOVING SOUTH THROUGH
NORTHERN MIDDLE TENNESSEE. AT 415 PM CDT...THE GUST FRONT EXTENDED
FROM CELINA...TO HARTSVILLE...INTO NORTHERN DAVIDSON COUNTY...JUST
NORTH OF GOODLETTSVILLE...TO ASHLAND CITY...TO NEAR TENNESSEE RIDGE
IN HOUSTON COUNTY. AS THE GUST FRONT PASSES LOOK FOR A SUDDEN SHIFT
IN THE WIND DIRECTION TO THE NORTH...ALONG WITH AN INCREASE IN
SPEED...WITH SOME GUSTS AS HIGH AS 40 MPH POSSIBLE. BEHIND THE GUST
FRONT LOOK FOR THUNDERSTORMS TO MOVE IN FROM THE NORTH. THEY SHOULD
BE BRIEF BUT HEAVY DOWNPOURS AND GUSTY WINDS CAN BE EXPECTED ALONG
WITH DANGEROUS LIGHTNING.

BOYD