Special Weather Statement, NWS Huntsville, AL

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE HUNTSVILLE AL
1221 PM CDT WED JUL 18 2012

.UPDATE...
FOR 18Z TAFS

&&

.DISCUSSION...
/ISSUED 1030 AM CDT WED JUL 18 2012/
SFC PATTERN REMAINS FAIRLY UNCHANGED THIS WED MORNING...WITH HIGH
PRESSURE DRAPED ACROSS NRN MS/AL LEADING INTO ERN TN. WEAK UPPER
RIDGE ALSO REMAINS FAIRLY STAGNANT ACROSS THE MIDWEST/LOWER MS VALLEY
REGIONS. UPPER WAVES EMBEDDED ALONG THE ERN FRINGE OF THE RIDGE
PATTERN/WEAK UPPER TROUGH AXIS ACROSS THE MID ATLANTIC STATES WILL
AGAIN PROVIDE THE PRIMARY FOCUS MECH FOR CONVECTIVE DEVELOPMENT LATER
TODAY. THIS ENERGY COUPLED WITH REMNANT OUTFLOW BOUNDARIES FROM LAST
NIGHT'S CONVECTION SHOULD ENHANCE THE DEVELOPMENT OF SCT/NUMEROUS
SHOWERS/TSTMS THIS AFTERNOON...PROVIDED THE ENERGY FROM THESE PASSING
DISTURBANCES ALOFT BECOMES BETTER ORGANIZED. IN ANY CASE...WITH A
RELATIVELY LIGHT TRANSPORT/FLOW PATTERN IN PLACE...ANY STORMS WILL BE
CAPABLE OF LOCALLY HEAVY DOWNPOURS AND GUSTY OUTFLOW WINDS. A
MARGINAL SVR TSTM/MICROBURST THREAT DOES EXISTS GIVEN A SOMEWHAT
INVERTED V THERM PROFILE XCPETD TO EVOLVE LATER TODAY. ANY STRONG/SVR
TSTMS THOUGH WILL HAVE TO OVERCOME A SOMEWHAT CAPPED AIRMASS IN
PLACE...GIVEN THE LINGERING CLOUD COVER. EARLY MORNING CLOUD COVER
THOUGH SHOULD BEGIN TO DIMINISH...AS TOWERING CU FORMS WITH SFC BASED
INSTABILITY/BUOYANCY INCREASING. ONGOING FORECAST LOOKS TO HAVE THIS
OVERALL TREND WELL IN HAND...WITH AFTERNOON HIGHS CLIMBING INTO THE
LOWER/MID 90S RANGE...OR A FEW DEGREES ABOVE SEASONAL TRENDS.

09

&&

.AVIATION...SCT CONVECTION IS BEGINNING TO DEVELOP ACROSS PARTS OF
THE AREA WHERE DIURNAL HEATING IS BETTER ENHANCED. CONVECTION MAY
BECOME MORE NUMEROUS DURING THE LATE AFTERNOON/EARLY EVENING HRS.
HOWEVER...IT REMAINS DIFFICULT TO PINPOINT EXACTLY WHERE ANY
SHOWERS/TSTMS WILL DEVELOP IN RELATION TO THE TWO MAIN TERMINALS. AS
SUCH...WILL MAINTAIN PREVAILING VCTS IN THE TAFS THROUGH 01Z THU.
AMD/UPDATES THOUGH MAY BE REQUIRED PROVIDED ANY OF THIS ACTIVITY
APPROACHES ONE OF THE AIRPORTS...WITH CONDITIONS BRIEFLY LOWERING
INTO THE MVFR CAT IN/NEAR THE HEAVIER SHRA/TSRA. OTHERWISE...VFR
CONDITIONS ARE GENERALLY XPCTED THROUGH THE PERIOD. ANY CIGS LOOK TO
REMAIN NEAR OR ABOVE VFR LEVELS INTO THU.

&&

.PREV DISCUSSION...
/ISSUED 352 AM CDT WED JUL 18 2012/ IN THE EARLY MORNING HOURS...A
SMALL COMPLEX OF THUNDERSTORMS FUELED BY AN OUTFLOW BOUNDARY
CONTINUES TO SLIDE ACROSS THE SE PORTIONS OF THE CWA. MORE STRATIFORM
TRAILING PRECIP ASSOCIATED WITH THE ANVIL OF THE STORM IS ALLOWING
FOR PERIODIC LIGHTNING STRIKES ACROSS JACKSON/DEKALB COUNTIES IN
AL...WHILE THE MAIN CONVECTIVE DEVELOPMENT AND FREQUENT LIGHTNING
PRODUCERS PUSH ACROSS MARSHALL/MORGAN AND CULLMAN COUNTIES. SOME
GUSTY WINDS...HEAVY DOWNPOURS AND VERY SMALL HAIL HAVE BEEN NOTED
WITH THE STRONGER CORES OVERNIGHT BUT THE LOSS OF DAYTIME HEATING
GREATLY REDUCED THE SEVERITY OF STORMS.

THE STORMS OVERNIGHT/THIS MORNING DEVELOPED AROUND THE FRINGES OF A
WEAK LOW PRESSURE CIRCULATION THAT IS CENTERED OVER THE BEND OF
FLORIDA. POCKETS OF POSITIVE VORTICITY THAT ARE ROTATING AROUND THIS
SYSTEM HELPED SUPPORT STORM ORGANIZATION IN THE SOUTHEAST YESTERDAY
AFTERNOON...AND WE WILL SEE A REPEAT PERFORMANCE TODAY. SHOULD SEE
MORE COVERAGE OVER OUR CWA THIS AFTERNOON BECAUSE THE LOW SHOULD
SLIDE NORTH EVER SO SLIGHTLY WHILE A WEAK SHORTWAVE IN THE MAIN
MIDLEVEL FLOW WILL SLIDE JUST A BIT MORE SOUTHEAST. THE STORMS THAT
DO DEVELOP WILL HAVE TO BE MONITORED AGAIN FOR STRONG/SEVERE WIND
POTENTIAL (HIGH CAPE VALUES AND MODERATE WINDEX VALUES ASSOC WITH AN
INVERTED V TYPE SOUNDING...ALTHOUGH DCAPE VALUES ARE REDUCED COMPARED
TO YESTERDAY). HEAVY DOWNPOURS (PWAT VALUES NEAR 2IN) AND FREQUENT
LIGHTNING WILL ALSO BE A CONCERN BUT HAIL LESS SO (DUE TO 15+KFT FZG
HEIGHTS).

THE END OF THE WEEK STILL LOOKS TO BRING INCREASING POP CHANCES AS
THE MID LEVEL LONGWAVE TROF DEEPENS AND THE AXIS SLIDES TOWARD THE
SE. A WEAK FRONTAL BOUNDARY WILL HELP FOCUS STORM DEVELOPMENT AND
POOL MOISTURE AHEAD OF IT LATE THURS-LATE FRI...WITH FROPA EXPECTED
DURING THE DAY SAT. THE CLEARING BEHIND THE FRONT SHOULD STILL BE
SLOW ENOUGH TO KEEP TEMPS FROM REBOUNDING TOO MUCH ON SATURDAY.

FOR THE END OF THE WEEKEND INTO NEXT WEEK...MODELS NOW INDICATE THE
RIDGE ACROSS THE CENTRAL CONUS TO BE CENTERED SLIGHTLY FURTHER NORTH
WHILE THE ATLANTIC HIGH WILL BE STRONGER. THE MORE SOUTHERLY SOLN SEEN
YESTERDAY IN THE MODELS POINTED TO BETTER CHANCES FOR A DRIER/QUIETER
PERIOD TO START THE NEXT WORK WEEK...PUSHING THE FRONT TO STALL NEAR
THE COAST. BUT THE FRONT MAY NOW STALL FURTHER NW TOWARD OUR AREA SO
HAVE HAD TO UP POP CHANCES FOR MONDAY/TUESDAY DUE TO BETTER RETURN
FLOW PROGGED TO SETUP ACROSS THE DEEP SOUTH. THE HIGHER CLOUD COVER
ASSOCIATED WITH THIS SOLN WILL ALSO KEEP HIGHS CLOSER TO THE 90
DEGREE MARK THROUGH THE EXTENDED.

CCC

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

FOR MORE INFORMATION PLEASE VISIT OUR WEBSITE AT
WEATHER.GOV/HUNTSVILLE.

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HUNTSVILLE AL
1235 PM CDT WED JUL 18 2012

ALZ001>010-016-TNZ076-096-097-191015-
LAUDERDALE-COLBERT-FRANKLIN AL-LAWRENCE-LIMESTONE-MADISON-MORGAN-
MARSHALL-JACKSON-DEKALB-CULLMAN-MOORE-LINCOLN-FRANKLIN TN-
1235 PM CDT WED JUL 18 2012

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

.DAY ONE...THIS AFTERNOON AND TONIGHT...

NUMEROUS AFTERNOON AND EVENING THUNDERSTORMS ARE EXPECTED ACROSS THE
CENTRAL TENNESSEE VALLEY...WITH THE COVERAGE OF STORMS DIMINISHING
AFTER MIDNIGHT. A FEW STRONG TO MARGINALLY SEVERE STORMS REMAIN
POSSIBLE...WITH THE PRIMARY THREAT COMING FROM DAMAGING WIND GUSTS
AROUND 60 MPH. OTHERWISE...GUSTY WINDS...LOCALLY HEAVY DOWNPOURS AND
FREQUENT LIGHTNING ARE POSSIBLE WITH ANY THUNDERSTORMS.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY...

THUNDERSTORMS WILL BE LIKELY DURING THE AFTERNOON AND EVENING HOURS
ON BOTH THURSDAY AND FRIDAY. HOWEVER...AS A WEAK COLD FRONT PUSHES
SOUTHWARD ON SATURDAY...CHANCES FOR STORMS WILL BEGIN TO DIMINISH
FROM NORTHWEST TO SOUTHEAST. THE FRONT IS EXPECTED TO STALL AROUND
THE AREA...WITH A LOW CHANCE OF MAINLY AFTERNOON STORMS CONTINUING
THROUGH THE BEGINNING OF NEXT WEEK.

.SPOTTER CALL TO ACTION STATEMENT...

ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT PERSONNEL IS
NOT ANTICIPATED AT THIS TIME. HOWEVER...TIMELY REPORTS OF GUSTY
WINDS WILL BE GREATLY APPRECIATED.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HUNTSVILLE AL
227 PM CDT WED JUL 18 2012

ALZ006-182000-
MADISON-
227 PM CDT WED JUL 18 2012

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWEST MADISON COUNTY UNTIL
300 PM CDT...

AT 227 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED THAT
THUNDERSTORMS WERE RAPIDLY DEVELOPING NEAR TRIANA...OR NEAR THE
HUNTSVILLE INTERNATIONAL AIRPORT IN MADISON...MOVING SOUTH AT 5 MPH.

WINDS UP TO 40 MPH...FREQUENT CLOUD TO GROUND LIGHTNING...AND HEAVY
DOWNPOURS ARE EXPECTED WITH THESE STORMS.

* LOCATIONS IN OR NEAR THE PATH INCLUDE...
  TRIANA.

THIS THUNDERSTORM COULD INTENSIFY QUICKLY...SO BE READY TO ACT IF A
WARNING IS ISSUED.

&&

LAT...LON 3458 8679 3472 8678 3471 8669 3457 8663
      3456 8667 3458 8668 3459 8671 3456 8675
      3456 8679
TIME...MOT...LOC 1927Z 003DEG 6KT 3463 8676

DJN

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HUNTSVILLE AL
235 PM CDT WED JUL 18 2012

ALZ009-182000-
JACKSON-
235 PM CDT WED JUL 18 2012

...SIGNIFICANT WEATHER ADVISORY FOR JACKSON COUNTY UNTIL 300 PM
CDT...

AT 230 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM NEAR HOLLYTREE...OR 14 MILES NORTHWEST OF
SCOTTSBORO...MOVING SOUTH AROUND 10 MPH.

PEA SIZE HAIL...WINDS UP TO 40 MPH...FREQUENT CLOUD TO GROUND
LIGHTNING...AND HEAVY DOWNPOURS ARE EXPECTED WITH THIS STORM.

* LOCATIONS IN OR NEAR THE PATH INCLUDE...
  TRENTON.
  GARTH.
  LIM ROCK...LARKINSVILLE.

THIS THUNDERSTORM COULD INTENSIFY QUICKLY...SO BE READY TO ACT IF A
WARNING IS ISSUED.

STAY TUNED TO NOAA WEATHER RADIO...COMMERCIAL RADIO...OR YOUR LOCAL
TELEVISION STATIONS FOR LATER STATEMENTS AND POSSIBLE WARNINGS
CONCERNING THIS WEATHER SITUATION.

&&

LAT...LON 3461 8633 3462 8635 3495 8625 3494 8611
      3460 8605
TIME...MOT...LOC 1935Z 003DEG 10KT 3480 8620

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HUNTSVILLE AL
242 PM CDT WED JUL 18 2012

ALZ005-006-182015-
LIMESTONE-MADISON-
242 PM CDT WED JUL 18 2012

...SIGNIFICANT WEATHER ADVISORY FOR EASTERN LIMESTONE AND SOUTHWEST
MADISON COUNTIES UNTIL 315 PM CDT...

AT 242 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED THAT
THUNDERSTORMS WERE RAPIDLY DEVELOPING NEAR CAPSHAW...OR NEAR
MADISON...MOVING SOUTH AT 10 MPH.

WINDS UP TO 40 MPH...FREQUENT CLOUD TO GROUND LIGHTNING...AND HEAVY
DOWNPOURS ARE EXPECTED WITH THESE STORMS.

* LOCATIONS IN OR NEAR THE PATH INCLUDE...
  MADISON.
  BELLE MINA.
  REDSTONE ARSENAL.
  MOORESVILLE.
  TRIANA.

SEEK SHELTER AND STAY AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED.

&&

LAT...LON 3482 8672 3459 8659 3458 8661 3455 8664
      3455 8666 3456 8668 3458 8668 3459 8671
      3455 8676 3458 8692 3460 8694 3484 8694
TIME...MOT...LOC 1942Z 348DEG 9KT 3471 8682

DJN

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HUNTSVILLE AL
248 PM CDT WED JUL 18 2012

ALZ006-TNZ096-182030-
LINCOLN-MADISON-
248 PM CDT WED JUL 18 2012

...SIGNIFICANT WEATHER ADVISORY FOR LINCOLN AND MADISON COUNTIES
UNTIL 330 PM CDT...

AT 248 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM NEAR COLDWATER...OR 10 MILES SOUTHWEST OF
FAYETTEVILLE...MOVING SOUTH AROUND 10 MPH.

PEA SIZE HAIL...WINDS UP TO 40 MPH...FREQUENT CLOUD TO GROUND
LIGHTNING...AND HEAVY DOWNPOURS ARE EXPECTED WITH THIS STORM.

* LOCATIONS IN OR NEAR THE PATH INCLUDE...
  TAFT...BLANCHE.
  CASH POINT.
  ELKWOOD...TONEY.

THIS THUNDERSTORM COULD INTENSIFY QUICKLY...SO BE READY TO ACT IF A
WARNING IS ISSUED.

STAY TUNED TO NOAA WEATHER RADIO...COMMERCIAL RADIO...OR YOUR LOCAL
TELEVISION STATIONS FOR LATER STATEMENTS AND POSSIBLE WARNINGS
CONCERNING THIS WEATHER SITUATION.

&&

LAT...LON 3517 8663 3486 8656 3487 8679 3499 8679
      3500 8684 3518 8680
TIME...MOT...LOC 1947Z 003DEG 7KT 3508 8672

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HUNTSVILLE AL
257 PM CDT WED JUL 18 2012

ALZ009-182045-
JACKSON-
257 PM CDT WED JUL 18 2012

...SIGNIFICANT WEATHER ADVISORY FOR JACKSON COUNTY UNTIL 345 PM
CDT...

AT 254 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM NEAR LARKIN...OR 14 MILES EAST OF MOORES MILL...
MOVING SOUTH AROUND 15 MPH.

PEA SIZE HAIL...WINDS UP TO 40 MPH...FREQUENT CLOUD TO GROUND
LIGHTNING...AND HEAVY DOWNPOURS ARE EXPECTED WITH THIS STORM.

* LOCATIONS IN OR NEAR THE PATH INCLUDE...
  PRINCETON.
  HOLLYTREE...SKYLINE.
  TRENTON...GARTH.
  LIM ROCK...LARKINSVILLE.
  PAINT ROCK.

THIS THUNDERSTORM COULD INTENSIFY QUICKLY...SO BE READY TO ACT IF A
WARNING IS ISSUED.

STAY TUNED TO NOAA WEATHER RADIO...COMMERCIAL RADIO...OR YOUR LOCAL
TELEVISION STATIONS FOR LATER STATEMENTS AND POSSIBLE WARNINGS
CONCERNING THIS WEATHER SITUATION.

&&

LAT...LON 3463 8636 3474 8635 3479 8633 3482 8635
      3483 8633 3486 8634 3490 8634 3491 8631
      3493 8633 3494 8629 3492 8627 3493 8626
      3498 8631 3499 8618 3467 8603
TIME...MOT...LOC 1957Z 355DEG 14KT 3489 8629

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HUNTSVILLE AL
302 PM CDT WED JUL 18 2012

ALZ006-009-182030-
JACKSON-MADISON-
302 PM CDT WED JUL 18 2012

...SIGNIFICANT WEATHER ADVISORY FOR JACKSON AND MADISON COUNTIES
UNTIL 330 PM CDT...

AT 301 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING
A STRONG THUNDERSTORM 5 MILES EAST OF NEW MARKET...OR 12 MILES
NORTHEAST OF MOORES MILL...MOVING SOUTH AT 20 MPH.

PEA SIZE HAIL...WINDS UP TO 50 MPH...FREQUENT CLOUD TO GROUND
LIGHTNING...AND HEAVY DOWNPOURS ARE EXPECTED WITH THIS STORM.

* LOCATIONS IN OR NEAR THE PATH INCLUDE...
PLEVNA AND RURAL AREAS OF NORTHEAST MADISON AND NORTHWEST JACKSON
COUNTY.

THIS THUNDERSTORM COULD INTENSIFY QUICKLY...SO BE READY TO ACT IF A
WARNING IS ISSUED.

&&

LAT...LON 3484 8622 3485 8640 3499 8641 3499 8626
TIME...MOT...LOC 2001Z 338DEG 16KT 3492 8633

DJN