Severe Thunderstorm Warning 232, NWS Birmingham, AL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BIRMINGHAM, AL
251 PM CDT THU APR 27 2000

TIGHT AND VIGOROUS VORT MAX ASSOCIATED WITH THE MONTANA CLIPPER OVER
MO WILL REACH THE TN VALLEY THIS EVENING.  ACCOMPANYING SURFACE
LOW FORECAST BY THE ETA TO BY NEAR HSV BY 06Z. THUNDERSTORMS HAVE
BROKEN OUT OVER SOUTHERN IL AND SE MO AND THESE ARE EXPECTED TO
INCREASE IN COVERAGE AND INTENSITY AS THEY PLUNGE SSE TOWARD THE
TN VALLEY OF AL THIS EVENING.  MOISTURE IS LIMITED BUT DYNAMICS ARE
FAIRLY STRONG AND LAPSE RATES ARE STEEP.  EXPECT THUNDERSTORMS TO
SLOWLY DIMINISH WITH THE LOSS OF SURFACE HEAT LATER DURING THE
EVENING AND THE SLIGHT RISK AREA IS SO FAR CONFINED TO A FAIRLY SMALL
PART OF N AND NW AL.  HOWEVER WITH DEWPOINTS STILL ON THE RISE...THE
ETA SURFACE LIS ARE FORECAST TO STAY NEGATIVE THRU 06Z. IF THE
STORMS STAY STRONG THAT LONG THEN PARTS OF CENTRAL AL COULD BE
AFFECTED BY SEVERE WEATHER.  ISOLATED SUPER CELLS POSSIBLE TN
VALLEY EARLY THIS EVENING AND STORMS COULD EVOLVE INTO A NNE-SSW LINE
LATER.

BELIEVE MOST PRECIP WILL BE OUT OF AL WELL BEFORE MORNING BUT LOOK
FOR RESIDUAL MOISTURE WEST OF THE LOW AND LINGERING COLD AIR ALOFT TO
BE SUFFICIENT FOR THUNDERSTORM REDEVLOPMENT DURING THE DAY FRIDAY...
MORE NUMEROUS NORTH AND EAST OF BIRMINGHAM.

SCATTERED CLOUDINESS REFORMING OVER THE EAST ON SATURDAY BUT
GENERALLY FAIR WEATHER FOR THE WEEKEND WITH TEMPS WARMING UP AS THE
UPPER RIDGE BUILDS EASTWARD.

HSV BB 051/071 046/075 046 07730
BHM BU 053/074 045/076 046 07610
MGM BU 057/075 047/082 047 076-0=

.BHM...NONE.

07

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ALZ001>038-040>050-272130-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BIRMINGHAM AL
200 PM CDT THU APR 27 2000

HAZARDOUS WEATHER OUTLOOK FOR NORTH AND CENTRAL ALABAMA.

A SURFACE LOW PRESSURE SYSTEM, CURRENTLY MOVING SOUTHEASTWARD OVER
SOUTHEASTERN MISSOURI, WILL BE CONTINUE TOWARD ALABAMA THROUGHOUT THE
EVENING. THIS SYSTEM WILL BEGIN TO AFFECT OUR WEATHER LATER ON
THIS EVENING AND DURING THE OVERNIGHT HOURS.  SHOWERS AND A FEW
THUNDERSTORMS SHOULD FORM OUT AHEAD OF THE LOW AS IT MOVES TOWARDS
THE STATE TONIGHT.

ISOLATED SUPERCELLS, WITH LARGE HAIL, DAMAGING WINDS, AND TORNADOES
COULD BE OCCURRING ACROSS WESTERN TENNESSEE AND NORTHERN MISSISSIPPI
BY LATE THIS AFTERNOON.  THESE COULD BE MOVING INTO NORTHWESTERN
ALABAMA BEFORE SUNSET.  AS THE AFTERNOON DISCUSSION OUT OF SPC
STATES, THE SEVERE POTENTIAL SHOULD GRADUALLY DECREASE AFTER DARK.

EXPECT SHOWERS AND STORMS TO CONTINUE OVERNIGHT, AND THEY SHOULD MOVE
OVER MUCH OF NORTHERN AND CENTRAL ALABAMA DURING THE NIGHT TIME
HOURS. ALTHOUGH THE INTENSITY OF THE STORMS SHOULD HAVE DECREASED BY
THEN, AN ISOLATED SEVERE THUNDERSTORM COULD STILL BE ENCOUNTERED
OVERNIGHT.

ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT PERSONNEL COULD
BECOME NECESSARY THIS EVENING AND TONIGHT, ESPECIALLY OVER
NORTHWESTERN PORTIONS OF ALABAMA.  EMERGENCY MANAGEMENT AND SPOTTERS
OVER THE REMAINDER OF THE FORECAST AREA SHOULD MONITOR THE WEATHER
SITUATION LATER ON TONIGHT, IN THE EVENT THAT THE SEVERE WEATHER
POTENTIAL CHANGES OVER YOUR AREA.

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