Severe Thunderstorm Warning 242, NWS Hastings, NE

SOUTH CENTRAL NEBRASKA/NORTH CENTRAL KANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
349 PM CDT SAT AUG 9 2003

12Z UPPER AIR DATA ANALYSIS AND WATER VAPOR IMAGERY CONTINUES TO
DEPICT AN AMPLIFIED/BLOCKED PATTERN IN PLACE ACROSS MUCH OF NORTH
AMERICA. UPPER RIDGE REMAINS MAIN FEATURE ACROSS THE WESTERN/CENTRAL
CONUS...FLANKED BY EASTERN CONUS MEAN TROUGH AND ROBUST CLOSED LOW
PINWHEELING OFF THE PACIFIC NORTHWEST AROUND 135W.

LATEST SUBJECTIVE SURFACE ANALYSIS FEATURES HIGH PRESSURE RIDGE AXIS
FROM THE UPPER MISSISSIPPI VALLEY INTO EASTERN NEBRASKA. LOW
PRESSURE/TROUGH ORIENTED FROM THE DAKOTAS INTO THE NEBRASKA
PANHANDLE...AHEAD OF COLD FRONT EXTENDING FROM MONTANA TO NORTH
DAKOTA.

FORECAST FOCI ARE THUNDERSTORM CHANCES TONIGHT/SUNDAY/SUNDAY EVENING.

CONVECTIVE ACTIVITY WILL CONTINUE TO DEVELOP/ORGANIZE ACROSS SOUTH
DAKOTA AND WESTERN NEBRASKA THIS EVENING...WITH THIS LIKELY TO
PROPAGATE SOUTH/SOUTHEASTWARD INTO SOUTH CENTRAL NEBRASKA AND
POSSIBLY NORTH CENTRAL KANSAS LATER TONIGHT AND EARLY SUNDAY MORNING
SUPPORTED BY WEAK LLJ/WAA REGIME/MID LEVEL VORTICITY MAXIMA. POSSIBLY
A FEW SEVERE STORMS OVERNIGHT/EARLY SUNDAY -- NAMELY IN THE NORTH/
WEST QUADRANTS OF THE CWA -- HOWEVER PROBABLY MARGINAL/ISOLD AT BEST
GIVEN STABILIZING NOCTURNAL BOUNDARY LAYER BY THE TIME ACTIVITY WOULD
REACH THE AREA.

SUNDAYS FORECAST DETAILS CERTAINLY DEPENDENT ON DEGREE/COVERAGE OF
CONVECTIVE ACTIVITY LATER TONIGHT. SEMI-ORGANIZED MCS AND/OR
THUNDERSTORM CLUSTERS MAY BE ONGOING ACROSS PORTIONS OF THE CWA
SUNDAY MORNING...AS POST-CONVECTIVE ENVIRONMENT MAY ACT TO STABILIZE
ATMOSPHERE FOR A TIME WITH SUBSEQUENT LULL IN ACTIVITY. IN ALL...WILL
MAINTAIN LOW END TSTM POPS THROUGHOUT THE DAY ON SUNDAY...WITH
LINGERING POSSIBILITIES INTO THE EVENING MAINLY FOR THE EAST/SOUTH
CWA. THEREAFTER...DEVELOPING SUBSIDENCE LATE SUNDAY NIGHT INTO EARLY
NEXT WEEK BENEATH UPPER RIDGE.

IN THE EXTENDED...MEDIUM RANGE ENSEMBLE CONSENSUS SUGGESTS VERY
STAGNANT UPPER FLOW PATTERN WILL REMAIN IN PLACE THROUGH MUCH OF
NEXT WEEK. AS SUCH...MAINLY DRY SCENARIO PREVAILS...WITH PROGRESSIVE
WARM-UP INTO NEXT WEEKEND AS WESTERN/CENTRAL CONUS UPPER RIDGE
FURTHER AMPLIFIES/OVERSPREADS.

.GID...NONE.

GUYER

KSZ005>007-017>019-NEZ039>041-046>049-060>064-072>077-082>087-101200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HASTINGS NE
344 PM CDT SAT AUG 9 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTH CENTRAL NEBRASKA AND
PARTS OF NORTH CENTRAL KANSAS.

.DAY ONE...TONIGHT

SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE OVER ALL OF SOUTH CENTRAL
NEBRASKA AND PORTIONS OF NORTH CENTRAL KANSAS AFTER SUNSET TONIGHT.
THE BEST CHANCE FOR ANY SEVERE WEATHER WILL REMAIN ALONG AND NORTH
OF INTERSTATE 80. ISOLATED WIND GUSTS IN EXCESS OF 50 MPH AND PENNY
SIZED HAIL WILL BE POSSIBLE. HOWEVER...WIDESPREAD SEVERE WEATHER IS
NOT ANTICIPATED.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THUNDERSTORMS ARE POSSIBLE SUNDAY NIGHT MAINLY ALONG AND EAST OF
HIGHWAY 281 AS ANOTHER DISTURBANCE MOVES IN FROM THE NORTHWEST. IN
ADDITION...A SURFACE COLD FRONT IS EXPECTED TO MOVE IN FROM THE
NORTH.  ATMOSPHERIC INSTABILITY WILL INCREASE DURING THE DAYTIME DUE
TO HOT TEMPERATURES AND PLENTY OF LOW LEVEL MOISTURE. HOWEVER...WIND
SHEAR IN THE LOW LEVELS REMAINS WEAK.  LARGE HAIL AND DAMAGING WINDS
MAY OCCUR IN A FEW PLACES...BUT THE MAJORITY OF ANY STORMS THAT DO
FORM WILL REMAIN BELOW SEVERE LIMITS.

.SPOTTER INFORMATION STATEMENT...

STORM SPOTTER ACTIVATION WILL NOT BE NEEDED TONIGHT.

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