Severe Thunderstorm Warning 227, NWS Nashville, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
724 PM CDT SAT JUN 26 2010

.UPDATE...
CLOUD TOPS SHOWING A SLIGHT WARMING TREND AT THIS HOUR AS ISOLATED
THUNDERSTORMS...A FEW STRONG...ARE ONGOING ACROSS MAINLY THE
SOUTHWEST HALF OF MIDDLE TN. CONVECTION SHOULD CONTINUE TO WEAKEN
OVERNIGHT. HOWEVER...WITH A SLIGHT DEGREE OF MOISTURE ENHANCEMENT
BY 12Z COUPLED WITH A CONTINUATION OF WEAK EASTWARD MOVING
DISTURBANCES...A SLIGHT CHANCE OF SHOWERS OR THUNDERSTORMS
OVERNIGHT WILL BE KEPT IN THE FCST. WILL RAISE POPS TO 40 PERCENT
ACROSS THE SOUTHWEST GIVEN THE CURRENT RADAR TREND.

OTHERWISE...ONLY CHANGE WILL BE TOO ADD EXTRA CLOUDINESS TO
SOUTHWEST AREAS FOR THIS EVENING.

WILL GO AHEAD AND REISSUE THE ONE COUNTY ONE ZONE SET OF ZONES
WITH THE ABOVE CHANGE TO THE SKY GRIDS...AND POP AND WX GRIDS..

&&

.PREV DISCUSSION... /ISSUED 644 PM CDT SAT JUN 26 2010/

UPDATE...FOR 00Z TAFS.

AVIATION...
VERY WEAK SFC/LL BOUNDARY SHOWING UP ACROSS SW MIDDLE TN...WHICH IS
HELPING TO KEEP ISO STRONG STORMS GOING...ALTHOUGH DIURNAL AFFECTS
ARE A BIG PART AS WELL WITH ML/UL RIDGE OVER THE REGION. SHWRS/STORMS
EXPECTED TO DISSIPATED OVER NEXT HOUR OR SO...WITH LITTLE IF ANY
REDEVELOPMENT OVERNIGHT. TEMPERATURES WILL WARM RAPIDLY SUNDAY MORNING
LIKELY SETTING OFF ISO STORMS BEFORE 18Z...WHICH ARE EXPECTED TO
BECOME MORE NUMEROUS AFTER 18Z AS UPR FLOW FLATTENS SOME. PASSING STORMS
WILL REDUCE CEILINGS/VSBYS BRIEFLY...AS WELL AS LIGHT EARLY MORNING
FOG.

PREV DISCUSSION... /ISSUED 207 PM CDT SAT JUN 26 2010/

DISCUSSION...SCATTERED THUNDERSTORMS WERE OCCURRING OVER MID
TN...MAINLY OVER THE NASHVILLE AREA AND SOUTHWEST COUNTIES.
OTHERWISE CONDITIONS WEER PARTLY SUNNY WITH TEMPS IN THE LOWER 90S.
THE SAME AIR MASS WILL REMAIN OVER THE AREA TONIGHT AND SUNDAY.
MODELS INDICATE A SLIGHTLY WEAKENING RIDGE...AND A SWATH OF DEEPER
MOISTURE WITH SMALL DISTURBANCES LIFTING ACROSS THE AREA...SO THE
CHANCE FOR ISOLATED TO SCATTERED THUNDERSTORMS WILL CONTINUE
THROUGHOUT TONIGHT AND SUNDAY.

THE CHANCE FOR THUNDERSTORMS WILL INCREASE MONDAY...ESPECIALLY
TOWARD EVENING AS A COLD FRONT APPROACHES. ANY STORMS THROUGH THE
NEXT SEVERAL DAYS COULD BE BRIEFLY STRONG TO SEVERE WITH LOCALIZED
GUSTY WINDS..HEAVY DOWNPOURS AND FREQUENT LIGHTNING. WE SHOULD SEE
PRETTY GOOD COVERAGE OF HEAVY DOWNPOURS BY LATE MONDAY AS
PRECIPITABLE WATER VALUES EXCEED 2 INCHES. THE K INDEX WILL BE
QUITE HIGH AND STORM MOVEMENT WILL REMAIN FAIRLY SLOW.

THE FRONT WILL PUSH THROUGH OUR AREA MONDAY NIGHT INTO
TUESDAY...THEN RAIN CHANCES WILL DIMINISH. A COOLER AND DRIER AIR
MASS WILL PUSH IN FROM THE NORTH FOR THE REST OF THE WEEK. THE
UPPER RIDGE PATTERN THAT HAS PRODUCED HOT WX FOR MUCH OF JUNE WILL
SHIFT A LITTLE FARTHER WEST...GIVING US NORTH NORTHWEST FLOW AND
MUCH MORE PLEASANT CONDITIONS FOR THE END OF THE MONTH. ULTIMATELY
THE HEAT WILL RETURN...MODELS SHOW THE RIDGE BUILDING EASTWARD
AGAIN FOR NEXT WEEKEND.

&&

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

21

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
934 AM CDT SAT JUN 26 2010

TNZ005>011-022>034-056>066-075-077>080-093>095-271445-
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-
934 AM CDT SAT JUN 26 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MIDDLE TENNESSEE.

.DAY ONE...TODAY AND TONIGHT

HOT AND HUMID WEATHER...ALONG WITH WEAK SURFACE BOUNDARIES...WILL
HELP PRODUCE SCATTERED THUNDERSTORMS. A FEW OF THE STORMS COULD BE
STRONG TO BRIEFLY SEVERE THIS AFTERNOON AND EVENING. THE MAIN SEVERE
HAZARD WILL BE LOCALIZED DAMAGING WIND GUSTS. OTHERWISE...THE
SLOW MOVING STORMS WILL CONTAIN HEAVY RAINFALL AND FREQUENT
LIGHTNING.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

STRONG AND ISOLATED SEVERE THUNDERSTORMS WILL BE POSSIBLE AGAIN
SUNDAY AND MONDAY. WARM AND HUMID AIR WILL BE OVER THE
REGION...AND A COLD WILL BE APPROACHING.

.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

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
216 PM CDT SAT JUN 26 2010

TNZ027>030-059-061>064-075-262015-
BEDFORD-CANNON-DAVIDSON-DEKALB-MARSHALL-RUTHERFORD-SMITH-TROUSDALE-
WILLIAMSON-WILSON-
216 PM CDT SAT JUN 26 2010

...SIGNIFICANT WEATHER ADVISORY FOR BEDFORD...CANNON...DAVIDSON...
DEKALB...MARSHALL...RUTHERFORD...SMITH...TROUSDALE...WILLIAMSON AND
WILSON COUNTIES...

AT 213 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING
SEVERAL STRONG THUNDERSTORMS ACROSS WILSON...RUTHERFORD...SMITH AND
EASTERN WILLIAMSON. IN ADDITION TO GUSTY WINDS...A FEW STORMS WILL PRODUCE
LOCALLY HEAVY DOWNPOURS WITH RAINFALL AMOUNTS UP TO AN INCH IN A
HALF HOUR. STORM MOVEMENT SOUTHEAST AT 10 MPH.

WINDS 30 TO 40 MPH ARE EXPECTED WITH THESE STORMS.

BOYD

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
229 PM CDT SAT JUN 26 2010

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

0125 PM     TSTM WND DMG     SMYRNA                  35.98N 86.52W
06/26/2010                   RUTHERFORD         TN   PUBLIC

            TREES AND POWER LINES REPORTED DOWN IN THE SMYRNA AREA.
            REPORT RELAYED BY LOCAL TV STATION METEOROLOGIST WKRN.

&&

BBOYD

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
737 PM CDT SAT JUN 26 2010

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

0735 PM     HAIL             3 S NASHVILLE           36.13N 86.78W
06/26/2010  E1.00 INCH       DAVIDSON           TN   EMERGENCY MNGR

            QUARTER SIZE HAIL REPORTED AT INTERSECTION OF NOLENSVILLE
            RD AND HARDING PLACE.

&&

21