Tornado and Hail in Nebraska, May 9, 2001

SOUTH CENTRAL NEBRASKA/NORTH CENTRAL KANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
255 PM CDT WED MAY 9 2001

THUNDERSTORM INITIATION AND LOCATION THE MAIN PROBLEMS. SOME
SURPRISE HUH?

BELIEVE THE FOCUS TONIGHT IS ON TWO AREAS. THE FIRST IS NEAR
STALLING BOUNDARY TO OUR NORTH AND NORTHEAST. ADVECTION OF
LOW LEVEL MOISTURE IMPRESSIVE EASTERN/SOUTHERN CWFA. PARAMETERS
APPEAR TO SET UP JUST EAST OF US...AT LEAST EARLY TONIGHT...AS
WARM MID LEVEL TEMPERATURES ACTING TO CAP THINGS NOW. NO SIGN
YET THAT CAP IS WEAKENING IN CWFA. MODERATE RISK SNATCHES EAST
CWFA. M0DEL QPF DIFFERENCES WELL DOCUMENTED. THIS IS VERY
SIMILAR TO AN EVENT LAST WEAK WITH A STRONGER FRONT (CURRENTLY
OUR "REAL" FRONT IS WELL NORTH OF NEBRASKA) AND WAVE. ALL THE
ACTION WAS WELL NORTHEAST. WON/T DEVIATE TOO MUCH FROM SPC
OUTLOOK...BUT LOWER POPS SOME TONIGHT. THIS TREND WAS BORN OUT
IN THE MORNING GUIDANCE AS WELL.

OTHER AREA OF CONCERN IS JUST SOUTHWEST OF CWFA. LAPS DATA SUGGEST
THIS AN AREA OF WEAKENING CAP. TEMPERATURES IN THE UPPER 80S WITH
SUFFICIENT LOW LEVEL MOISTURE...ALBEIT MIXED OUT SOME AND SHALLOW.
DISCONTINUITY IS CURRENTLY A FOCUS FOR DEVELOPMENT IN SOUTHEAST
COLORADO...AND THERE ARE HINTS OF CU LINE FORMING TO THE NORTHEAST
ALONG MOISTURE BOUNDARY WHICH EXTENDS UP INTO SOUTHWEST NEBRASKA.
HAVING SAID THAT...WITH RESIST TIMING ANYTHING DOWN THERE AND
KEEP 30 POPS FOR THE CHANCE SOMETHING MIGHT MOVE INTO THAT AREA
THIS EVENING.

THURSDAY AFTERNOON AND EVENING COULD/SHOULD BE RATHER ACTIVE
WITH WAVE TO SLIDE ALONG STALLED FRONTAL BOUNDARY IN SOUTHERN
CWFA. COMPROMISE OF LOW LEVEL MOISTURE FIELDS LOOK APPROPRIATE
BUT OVERALL...CONDITIONS SETTING UP FOR SEVERE WEATHER. HEAVY
RAIN IN THE SOUTHEAST WITH PW APPROACHING 1.5 INCHES...MAINLY
OVER AREAS OF MOST RECENT AND HEAVIEST RAINS. SLOWER FRONT LIKELY
MEANS SLIGHTLY WARMER TEMPERATURES THURSDAY THAN PREVIOUS RUN.
BELIEVE TREND ON FRIDAY WILL BE CLEARING DURING THE DAY...WITH
EXPECTED THURSDAY NIGHT CONVECTION PUSHING FRONT SOUTH OF CWFA.

THE EXTENDED LOOKS WARMER COME SUNDAY AND MONDAY...AHEAD OF FRONT
MOVING SOUTHEAST. COOLER TUESDAY AND WEDNESDAY. HAVE ADUJUSTED
TEMPERATURES ACCORDINGLY.

.GID...NONE.

MORITZ

KSZ005>007-017>019-NEZ039>041-046>049-060>064-072>077-082>087-100300-

SEVERE WEATHER OUTLOOK - SOUTH CENTRAL NEBRASKA/NORTH CENTRAL KANSAS
NATIONAL WEATHER SERVICE HASTINGS NE
610 PM CDT WED MAY 9 2001

...SPOTTER ACTIVATION WILL LIKELY BE NEEDED THIS EVENING ACROSS
PARTS OF SOUTH CENTRAL NEBRASKA AND NORTH CENTRAL KANSAS...

THUNDERSTORM DEVELOPMENT THIS EVENING WILL BE FOCUSED ALONG TWO LOW
LEVEL BOUNDARIES.  THUNDERSTORMS WILL DEVELOP ALONG A WEAK COLD
FRONT FROM NORTHEAST NEBRASKA INTO CENTRAL NEBRASKA.  THIS FRONT AND
ITS ASSOCIATED STORMS...WILL GRADUALLY SLIP SOUTHEAST THIS EVENING.

ANOTHER AREA OF THUNDERSTORM DEVELOPMENT IS EXPECTED ALONG A DRY
LINE FROM SOUTHWEST NEBRASKA ACROSS WESTERN KANSAS.  THESE STORMS
WILL MOVE EAST TOWARD HIGHWAY 183 DURING THE EVENING HOURS.

VERY STRONG INSTABILITY AND RELATIVELY WEAK ATMOSPHERIC SHEAR WOULD
SUGGEST THE MAIN THREAT WILL CONSIST OF LARGE HAIL AND DAMAGING
WINDS.  STILL...THE POSSIBILITY OF A FEW TORNADOES CANNOT BE RULED
OUT.

SEVERE THUNDERSTORM WATCHES ARE ALREADY IN EFFECT FOR PARTS OF
SOUTH CENTRAL NEBRASKA AND NORTH CENTRAL KANSAS.  CHECK YOUR LOCAL
FORECAST OR TUNE TO NOAA WEATHER RADIO FOR DETAILS.

DROZD