Severe Thunderstorm Warning 229, NWS Huntsville, AL

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE HUNTSVILLE AL
1235 PM CDT SUN JUN 26 2011

.UPDATE...FOR 18Z AVIATION DISCUSSION
&&

.AVIATION...
TS COMPLEX ARRIVING FROM THE NORTH WILL IMPACT BOTH TERMINALS EARLY
IN THE TAF PERIOD. HAVE MENTIONED MVFR CONDITIONS...BUT THEY MAY
DETERIORATE TO IFR BRIEFLY AS STORMS MOVE OVER THE AREA ALONG WITH
GUSTY WINDS. LINGERING LIGHT RAIN SHOWERS WILL BE POSSIBLE THROUGH
THE AFTERNOON HOURS. PATCHY FOG MAY DEVELOP LATE THIS EVENING
THROUGH THE EARLY MORNING...AND THIS MAY NEED TO BE ADDED WITH THE
00Z TAF ISSUANCE.
&&

.DISCUSSION.../ISSUED AT 1045 AM CDT SUN JUN 26 2011/
OUTFLOW BOUNDARY FROM EARLY MORNING MCS IN KENTUCKY IS RACING ITS
WAY SOUTH ACROSS THE TENNESSEE VALLEY. BEHIND IT...BRIEF GUSTY
NORTHERLY WINDS WILL USHER IN SIGNIFICANTLY COOLER TEMPERATURES. IN
FACT...THE 10AM OB FROM BNA IS STILL QUITE COOL /69 DEGREES/ DESPITE
SUNSHINE FOR THE GREATER PART OF THE LAST HOUR. A QUICK CHECK AT HSV
SUGGESTS THE HIGH TEMPERATURE PEAKED AT 86 JUST BEFORE THE OUTFLOW
ARRIVED...AND THEN COOLED INTO THE UPPER 70S. GIVEN THE STRENGTH OF
THE COLD AIR...AND THE CONTINUED COOL TEMPERATURE IN NASHVILLE AND
THE CLOUD COVER THAT WILL GENERALLY BE PRESENT THROUGH THE
DAY...BELIEVE THAT MAXIMUM TEMPERATURES TODAY WILL NOT CLIMB MUCH
HIGHER THAN PRE-OUTFLOW BOUNDARY VALUES. THIS WILL MEAN A PRETTY
LARGE GRADIENT OF HIGH TEMPERATURES...WITH VALUES IN THE UPPER 70S
IN THE NORTH...AND IN THE LOW 90S SOUTH.

HOWEVER...JUST BECAUSE IT MAY BE RELATIVELY COOL THROUGH MUCH OF
THE DAY NORTH OF THE RIVER...THAT DOES NOT NECESSARILY MEAN THAT
PRECIPITATION CHANCES ARE OVER AS WE MAY BE IMPACTED BY THE
THUNDERSTORM COMPLEX JUST NOW ENTERING EXTREME NORTHWEST TENNESSEE.
SOUTH OF THE RIVER WHERE THE STRENGTH OF THE OUTFLOW COOLING WILL BE
MORE LIMITED...WE MAY SEE THUNDERSTORM DEVELOPMENT AS TEMPERATURES
RISE THROUGH THE MIDDAY AND EARLY AFTERNOON.

SO WHILE THERE ARE TWO POTENTIAL GENESIS REGIONS FOR THUNDERSTORMS
LATE THIS MORNING AND AFTERNOON...ANY STORMS THAT ARE ABLE TO
DEVELOP WILL BE ABLE TO TAP INTO AN AIRMASS WITH MODERATE CAPE AND
PRODUCE GUSTY OR DAMAGING WINDS AND HAIL. GRIDS WERE TWEAKED FOR
TEMPERATURES AND UPDATED ZONES FORTHCOMING SHORTLY.
&&

.HUN WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
TN...NONE.
&&

JLL

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HUNTSVILLE AL
1245 PM CDT SUN JUN 26 2011

ALZ001>010-016-TNZ076-096-097-271000-
LAUDERDALE-COLBERT-FRANKLIN AL-LAWRENCE-LIMESTONE-MADISON-MORGAN-
MARSHALL-JACKSON-DEKALB-CULLMAN-MOORE-LINCOLN-FRANKLIN TN-
1245 PM CDT SUN JUN 26 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH ALABAMA AND PORTIONS
OF SOUTHERN MIDDLE TENNESSEE.

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

A COMPLEX OF SHOWERS AND THUNDERSTORMS WILL SINK SOUTH ACROSS THE
REGION...IMPACTING NORTHERN ALABAMA AND SOUTHERN MIDDLE TENNESSEE
THROUGH THE AFTERNOON HOURS. WELL AHEAD OF THIS COMPLEX...ISOLATED
TO SCATTERED THUNDERSTORMS MAY DEVELOP IN A WARM AND UNSTABLE
ENVIRONMENT.

ANY OF THE STORMS THIS AFTERNOON AND EARLY EVENING MAY BECOME
SEVERE...CAPABLE OF GUSTY OR DAMAGING WINDS ALONG WITH LARGE HAIL.
THE THREAT FOR SEVERE WEATHER WILL END AS THE THUNDERSTORM COMPLEX
SINKS SOUTH OF THE AREA EARLY THIS EVENING.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY...

SCATTERED ORGANIZED THUNDERSTORM ACTIVITY IS POSSIBLE ON TUESDAY AND
PERHAPS TUESDAY NIGHT AS A COLD FRONT MOVES INTO THE REGION. SOME
STRONG TO SEVERE STORMS ARE POSSIBLE...WITH THE POTENTIAL FOR
DAMAGING WINDS AND HAIL.

ISOLATED MAINLY AFTERNOON THUNDERSTORMS ARE OTHERWISE POSSIBLE ON
SATURDAY. A FEW STRONG STORMS REMAIN POSSIBLE AS WELL...WITH THE
PRIMARY WEATHER THREATS BEING GUSTY WINDS AND SMALL HAIL.

.SPOTTER CALL TO ACTION STATEMENT...

ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT PERSONNEL MAY
BE REQUESTED LATER TODAY.

JLL

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HUNTSVILLE AL
117 PM CDT SUN JUN 26 2011

ALZ001-002-005-261900-
COLBERT-LAUDERDALE-LIMESTONE-
117 PM CDT SUN JUN 26 2011

...SIGNIFICANT WEATHER ADVISORY FOR NORTHERN COLBERT...LAUDERDALE AND
WESTERN LIMESTONE COUNTIES UNTIL 200 PM CDT...

AT 116 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM SAVANNAH TO PULASKI
TENNESSEE...MOVING SOUTH AT 30 MPH.

PENNY SIZE HAIL...WINDS UP TO 50 MPH...AND FREQUENT CLOUD TO GROUND
LIGHTNING ARE EXPECTED WITH THESE STORMS.

* LOCATIONS IN OR NEAR THE PATH INCLUDE...
  ZIP CITY...THREET.
  WRIGHT...CLOVERDALE.
  FLORENCE...ROGERSVILLE.
  MUSCLE SHOALS...ATHENS.

THE GUSTY WINDS WILL BE CAPABLE OF KNOCKING DOWN SMALL TREES...TREE
LIMBS...AND POWERLINES. SEEK SAFE SHELTER UNTIL THE STORM HAS PASSED.

IF ON OR NEAR WHEELER OR PICKWICK LAKES...GET OUT OF THE WATER AND
MOVE INDOORS OR INSIDE A VEHICLE. IF YOU CAN HEAR THUNDER...YOU ARE
CLOSE ENOUGH TO BE STRUCK BY LIGHTNING. MOVE TO SAFE SHELTER NOW.
DON'T BE CAUGHT ON THE WATER IN A THUNDERSTORM!

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 800 PM CDT SUNDAY
EVENING FOR NORTHERN ALABAMA AND CENTRAL TENNESSEE.

&&

LAT...LON 3501 8701 3479 8695 3475 8729 3481 8735
      3481 8739 3479 8742 3473 8743 3472 8812
      3489 8810 3492 8814 3501 8820
TIME...MOT...LOC 1816Z 345DEG 26KT 3518 8716 3511 8813

BCC