Hail and Damaging Wind in Nebraska, May 27, 2002

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
335 PM CDT MON MAY 27 2002

...SEVERE WEATHER THREAT THIS AFTERNOON AND EVENING MAIN CONCERN...

THE THREAT FOR SEVERE WEATHER WILL EXIST AGAIN THIS AFTERNOON AND
THIS EVENING ACROSS A MAJORITY OF THE CWA.  ABUNDANT SUNSHINE
THROUGHOUT THE DAY HAS ALLOWED SURFACE-BASED TEMPERATURES TO CLIMB
STEADILY TO AROUND 80 DEGREES IN MOST LOCATIONS.  EAST TO SOUTHEAST
WINDS CONTINUE TO ADVECT LOW LVL MOISTURE INTO THE AREA WITH
DEWPOINTS IN THE MID 50S TO LOWER 60S.  SURFACE-BASED LAPS CAPE
VALUES AT 19Z RANGE FROM 1500 J/KG NORTHERN PORTIONS TO 2800 J/KG
SOUTH.

LOW LEVEL CONVERGENCE IN EASTERN WYOMING HAD INDUCED THUNDERSTORM
DEVELOPMENT IN WEAK CAP REGIME.  THESE STORMS WILL TRACK EAST AT
AROUND 20 MPH INTO SVR TSTMS WATCH #345 ACROSS WESTERN NEBRASKA THIS
AFTERNOON AND EARLY EVENING.  AXIS OF H85 DEWPOINTS OF 8-12C EXTENDS
FROM NORTH CENTRAL KANSAS TO WESTERN CHERRY COUNTY...PROVIDING
ADEQUATE MOISTURE FEED INTO WATCH AREA.  CU FIELD DEVELOPMENT
PROGRESSIVELY UNDERWAY ACROSS THE NORTHWEST PORTION OF CWA.
FREEZING LEVEL NEAR 10K FT AGL AND STRONG UPDRAFTS SUPPORT LARGE
HAIL DEVELOPMENT...WHILE DRY MICROBURST DAMAGING WINDS POSSIBLE IN
THE WESTERN PORTION OF THE WATCH AREA WHERE DEWPOINTS ARE IN THE
LOWER 40S.

CONVECTION WILL INCREASE IN COVERAGE AND INTENSITY ACROSS THE
NORTHERN PORTION OF CWA DEVELOPING INTO A CONVECTIVE COMPLEX THAT
WILL MOVE EAST EARLY THEN SOUTHEAST OVERNIGHT.  INCREASING LOW LVL
JET COULD LEAD TO THUNDERSTORM DEVELOP PAST MIDNIGHT ACROSS THE
EASTERN PORTION OF CWA.

BOUNDARY LAYER MOISTURE TUESDAY/TUESDAY NIGHT...INCREASING
INSTABILITY IN THE AFTERNOON AND REMAINING OUTFLOW BOUNDARIES SHOULD
BE SUFFICIENT FOR THUNDERSTORM DEVELOPMENT.  WILL KEEP THUNDERSTORMS
IN FORECAST FOR THE SECOND AND THIRD PERIODS...AND IN THE EASTERN
PORTIONS FOR WEDNESDAY.  NO MAJOR CHANGES TO THE REMAINDER OF THE
FORECAST...BUT DID INTRODUCED A CHANCE OF THUNDERSTORMS DAY SEVEN
WITH UPPER TROUGH MOVING OVER NORTHERN PLAINS PER MRF.

.LBF...NONE.

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