Severe Thunderstorm Warning 2, NWS Huntsville, AL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HUNTSVILLE AL
319 PM CST THU MAR 9 2006

.SYNOPSIS...
UPPER LEVEL NEG TILT TROF AXIS ORIENTED FROM N TX INTO SE TX WITH 988MB
SFC LOW CENTERED OVER SRN MO AT 2000Z. SFC COLD FRONT IS LOCATED
FURTHER NW...ACROSS N AR AND OK.  SFC WARM FRONT EXTENDS S ACROSS
WRN TN/AL. DEWPTS IN UPPER 50S MOVING INTO N NW AL IN THE WARM
SECTOR. SQUALL LINE EXTENDING FROM JUST W OF KMSL TO KLFT IS
MARCHING EWD TWD THE AREA. IN THIS LINE...THERE HAVE BEEN EMBEDDED
BOW ECHOES/LEWPS AS IT MOVED ACROSS MS. THIS HAS RESULTED IN
SEVERAL WIND DAMAGE REPORTS ACROSS AR..W TN...N MS EARLIER TODAY.

.SHORT TERM...(TONIGHT THROUGH SUNDAY)...
MAIN CONCERN TONIGHT WILL BE THE EFFECTS OF SQUALL LINE AS IT
MOVES ACROSS TN VALLEY. INSTABILITY HAS BEEN LIMITED ACROSS TN
VALLEY THIS AFTERNOON...CAPE VALUES REMAIN BELOW 100 J/KG. 18Z
AREA SOUNDINGS SHOW VERY STRONG SPEAD SHEAR IN LOW LEVELS...0-3KM
HELICITY ARND 220M2/S2...BUT NOT MUCH VEERING WITHIN THIS LAYER.
LOW LEVEL LAPSE RATES HAVE BECOME DRY ADIAB AND THUS RATHER STEEP.
THIS IS VERY FAVORABLE FOR MOMENTUM TRANSPORT TWD SFC...THAT IS
COMMON WITH NEG TILT TROF. SINCE LOW LEVELS DO NOT APPEAR VERY
FAVORABLE FOR TORNADIC ACTIVITY...BELIEVE THE MAIN THREAT FOR TONIGHT
ACROSS CWA WILL BE DAMAGING WINDS. THUS CWA WILL REMAIN UNDER A
SVR WATCH THIS EVENING.

LINE SHOULD QUICKLY MOVE E ACROSS AREA...HSV ARND 0-1Z...EXIT NE
AL BEFORE MIDNIGHT. SOME STRATIFORM PRECIP WILL LIKELY LINGER BEHIND
THE MAIN CONVECTIVE LINE.

LOW LEVEL WINDS WILL REMAIN STRONG AHEAD OF SQUALL LINE...COULD
GET SOME NON CONVECTIVE GUSTS TO 40 MPH...ESPECIALLY IN HIGHER
ELEVATIONS. WINDS SHOULD QUICKLY DECREASE AFTER SQUALL LINE
PASSES. THUS WILL KEEP WIND ADVISORY GOING THROUGH MIDNIGHT.

PRECIP WILL EXIT THE AREA AFTER MIDNIGHT...BUT DO NOT BELIEVE SFC
COLD FRONT MAKES IT THIS FAR S. SQUALL LINE WILL HAVE STABILIZED
THE ATMOS...KEEPING TOMORROW DRY. FRONT STALLS JUST NW OF TN
VALLEY ON FRIDAY...KEEPING AREA IN SRLY FLOW AND GULF OPEN FOR
BUSINESS. UPPER S/W EJECTS FROM BASE OF L/W TROF AND MOVES INTO
PLAINS FRI NIGHT. GFS AND NAM HAVE DIFFERING SOLN TO JUST WHAT
WILL OCCUR THIS WEEKEND. THIS IS DUE TO PLACEMENT OF STALLED FRONT.
WILL SIDE WITH DRIER NAM WHICH PLACES FRONT FURTHER N...AS
EXPECTED.

FRONT MOVES FURTHER N FRIDAY NIGHT ALLOWING DEEPER GULF MOISTURE TO
ENTER THE REGION ON SAT. MAY HAVE SOME TSTM DEVELOP SOMEWHERE ACROSS
THE AREA FRI NIGHT...SAT AND SUN AS A RESULT.

.LONG TERM...(MONDAY THROUGH THURSDAY)...
GUIDANCE BEING RATHER CONSISTENT WITH L/W TROF MOVING INTO CENTRAL
US MONDAY AND PUSHING A COLD FRONT ACROSS MS RIVER VALLEY ON MONDAY.
STRONG LOW LEVEL WINDS...GOOD DIFFLUENCE ALOFT AND DEWPTS NEAR 60
WILL BE IN PLACE ACROSS THE AREA AS THIS FRONT APPROACHES. SO
POSSIBLY WILL GET SOME TSTMS DEVELOP AHEAD OF FRONT ACROSS MS/AL/TN
MON AFTERNOON.

UPPER TROF NEARS AND BECOMES LESS POS TILTED...INCR SHEAR ACROSS THE
REGION. SO MAY SEE ANOTHER LINE OF TSTMS FORM ALONG THE COLD FRONT
AND MOVE ACROSS SE US MON NIGHT. FEELING A LITTE MORE CONFIDENT
ABOUT THE COLD FRONT MAKING IT ACROSS THE TN VALLEY MON NIGHT.
RAIN MAY LINGER THROUGH TUE MORN...UNTIL UPPER TROF AXIS SWINGS
THROUGH. SFC HIGH MOVES INTO SE ON WED AND GRADUALLY MOVES
E...ALLOWING WINDS TO BECOME MORE SRLY AGAIN ON THU. THUS APPEARS
A DRY MIDDLE OF THE WEEK MAY BE IN STORE FOR TN VALLEY.

&&

.PRELIMINARY POINT TEMPS/POPS...
HUNTSVILLE    52  74  56  76 / 100  10  20  40
SHOALS        50  74  57  76 / 100  10  20  40
CULLMAN       51  75  57  78 / 100  10  20  40
FAYETTEVILLE  50  72  54  75 / 100  10  20  40
FORT PAYNE    51  73  55  76 / 100  10  20  40

&&

.HUN WATCHES/WARNINGS/ADVISORIES...
AL...WIND ADVISORY UNTIL MIDNIGHT FRIDAY FOR THE FOLLOWING ZONES:
     COLBERT...CULLMAN...DE KALB...FRANKLIN AL...JACKSON...
     LAUDERDALE...LAWRENCE...LIMESTONE...MADISON...MARSHALL...
     AND MORGAN.

TN...WIND ADVISORY UNTIL MIDNIGHT FRIDAY FOR THE FOLLOWING ZONES:
     FRANKLIN TN...LINCOLN...AND MOORE.

&&

PG

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HUNTSVILLE AL
255 PM CST THU MAR 9 2006

ALZ001>010-016-TNZ076-096-097-100330-
COLBERT-CULLMAN-DE KALB-FRANKLIN AL-FRANKLIN TN-JACKSON-LAUDERDALE-
LAWRENCE-LIMESTONE-LINCOLN-MADISON-MARSHALL-MOORE-MORGAN-
255 PM CST THU MAR 9 2006

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

.DAY ONE...THROUGH TONIGHT...

A LINE OF STRONG TO SEVERE THUNDERSTORMS WILL APPROACH NORTHWEST
ALABAMA AROUND 3 PM. THIS LINE OF STORMS IS EXPECTED TO AFFECT
NORTHWEST ALABAMA BETWEEN 3 AND 5 PM. IN THE HUNTSVILLE AREA THE
STORMS ARE EXPECTED BETWEEN 4 AND 6 PM...AND THESE STORMS ARE
EXPECTED TO SPREAD EAST INTO NORTHEAST ALABAMA BETWEEN 5 AND 8
PM. THE SEVERE WEATHER THREAT WILL END BEFORE MIDNIGHT ACROSS THE
AREA.

THE MAIN THREAT WITH ANY STORMS WILL BE DAMAGING WINDS IN EXCESS OF
60 MPH. ISOLATED TORNADOES WILL ALSO BE POSSIBLE...ESPECIALLY WEST OF
INTERSTATE 65. IN ADDITION...THESE STORMS MAY CONTAIN HEAVY DOWNPOURS
AND HAIL UP TO THE SIZE OF PENNIES.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY...

THE PROBABILITY OF WIDESPREAD HAZARDOUS WEATHER IS LOW.

AN UNSETTLED WEATHER PATTERN WILL KEEP THE CHANCE OF SHOWERS AND
THUNDERSTORMS IN THE FORECAST FROM FRIDAY NIGHT THROUGH TUESDAY. A
COLD FRONT SHOULD MOVE ACROSS THE REGION NEXT TUESDAY...ENDING
THE RAIN CHANCES AND USHERING IN COOLER TEMPERATURES FOR THE MIDDLE
OF NEXT WEEK.

.SPOTTER CALL TO ACTION STATEMENT...

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

KTW