Severe Thunderstorm Warning 149, NWS Hastings, NE

SOUTH CENTRAL NEBRASKA/NORTH CENTRAL KANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
234 PM CDT THU JUL 27 2000

...MAIN CONCERN IS FOR PCPN OVERNIGHT...

A LOOK AT WV SATL IMAGERY THIS AFTERNOON SHOWS A NUMBER VORTS RIDING
OVER AND THRU THE UPPER LEVEL RIDGE WHICH IS SLOWLY PROGRESSING
EASTWARD INTO THE MID SECTIONS OF THE US. AT THE SFC UNORGANIZED
LOW PRESSURE WAS SITUATED TO THE WEST OVER THE HIGH PLAINS WITH
HIGH PRESSURE LOCATED NEAR THE GREAT LAKES. CLOSER TO OUR CWA...THE
ATMOSPHERE CONTINUE3S TO DESTABILIZE ACROSS SOUTH CENTRAL AND SOUTH
WEST NEBRASKA WHERE DAYTIME HEATING AND MOISTURE POOLING PREVAILS.
MSAS DATA IN THAT AREA INDICATES LIS AOB -10 WITH SFC DEW POINT
TEMPS IN THE LOWER 70S. THUNDERSTORMS PRESENTLY BEGINNING TO FIRE
SOUTH OF THE CWA IN CENTRAL KANSAS IN ASSOCIATION WITH LOW LEVEL
SPEED CONVERGENCE AND WAA LIFT.

AS FOR THE MODELS...THEYVE DONE A FAIR JOB INITIALIZING ON THE
LARGE SCALE OVER THE CONUS. BUT LOOKING CLOSER AT THE CENTRAL PLAINS
THE MODELS HAVE DIFFERING SOLUTIONS ON TIMING OF VORTS RIDING THRU
THE RIDGE IN THE NORTHERLY FLOW OVER THE NEXT 24HRS. A LOOK SATL PIX
MAY SUGGEST THAT THE ETA/AVN MAY BE MORE ON TRACK.

TONIGHT...SHOWERS AND THUNDERSTORMS LOOKS REASONABLE ACROSS THE
CWA. AS VORT MAX MOVE THRU THE AREA THIS WILL HELP DESTABILIZE AND
BREAK DOWN MODERATE CINH. COMPLEX SHOULD START SOMEWHERE ACROSS
SOUTH CENTRAL SOUTH DAKOTA AND WORK ITS WAY INTO NEBRASKA THIS
EVENING. AS FOR SEVERE POTENTIAL...SUPERCELLS SEEM RATHER UNLIKELY
AS PROGGED SFC-6KM WIND SHEAR REMAINS WELL BELOW 40KTS. GIVEN THE
LACK OF SHEAR EVENT LOOKS MORE MULTICELL WITH DAMAGING WINDS BEING
THE MAIN THREAT AS WELL AS SOME HAIL ALSO. THEREFORE WILL COVER
ENTIRE CWA WITH LIKELY WORDING.

FRIDAY...EXPECT LINGERING SHOWERS DURING THE MORNING HOURS OVER
KANSAS CWA. AS UPPER DISTURBANCE EXITS THOUGH...DECEASING CLOUDS IN
THE AFTERNOON VIA SUBSIDENCE SHOULD PREVAIL. SOME DAYTIME HEATING
EXPECTED WHICH SHOULD HELP TEMPS BE REALIZED NEAR GUIDANCE FORECAST.

FRIDAY NIGHT AND SATURDAY...DRY CONDITIONS SHOULD PREVAIL WITH PCPN
FOUND FURTHER SOUTHEAST OF THE CWA WHERE BETTER DYNAMICAL FORCING AND
LOW LEVEL MOISTURE WILL EXIST. FAN POPS LOOK A LITTLE AND TEMPS BIT
TOO COOL. WILL TREND MORE TOWARDS FWC HERE.

.GID...NONE

DEE

KSZ005>007-017>019-NEZ039>041-046>049-060>064-072>077-082>087-272130-

SEVERE WEATHER OUTLOOK - SOUTH CENTRAL NEBRASKA/NORTH CENTRAL KANSAS
NATIONAL WEATHER SERVICE HASTINGS NE
1200 PM CDT THU JUL 27 2000

...SPOTTER ACTIVATION WILL BE NEEDED LATE THIS AFTERNOON AND
TONIGHT...

SEVERAL FEATURES ARE COMING TOGETHER THIS AFTERNOON TO CREATE A
FAVORABLE ENVIRONMENT FOR SEVERE THUNDERSTORMS.  A STATIONARY FRONT
WILL CONTINUE TO STRETCH ALONG THE KANSAS-NEBRASKA BORDER INTO THE
EVENING HOURS.  AN UPPER LEVEL DISTURBANCE OVER EASTERN WYOMING AND
EASTERN COLORADO WILL MOVE INTO THE CENTRAL PLAINS BY LATE
AFTERNOON.  THESE TWO FEATURES WILL ACT TO TRIGGER THE DEVELOPMENT
OF THUNDERSTORMS BY LATE AFTERNOON.

ONCE THE STORMS DEVELOP...THEY SHOULD GROW RAPIDLY DUE TO THE DEGREE
OF INSTABILITY IN THE ATMOSPHERE.  DEWPOINT TEMPERATURES WILL HOVER
IN THE LOWER 70S.  AS SUNSHINE INCREASES THIS AFTERNOON...EXTREME
INSTABILITY WILL BE IN PLACE OVER THE AREA.

THE WIND PROFILE WILL PRIMARILY SUPPORT STORMS WITH LARGE HAIL AND
DAMAGING WINDS.  IF THE WINDS ALOFT BECOME STRONGER THIS EVENING...
THE POSSIBILITY OF A TORNADO WILL INCREASE.

THERE ARE TWO LIKELY TIMES AND AREAS FOR STORM DEVELOPMENT.  AFTER
3 PM TODAY STORMS MAY FORM OVER CENTRAL NEBRASKA OR NORTHERN
KANSAS...AND MOVE SLOWLY SOUTHEAST.  IN ADDITION...LATER THIS
EVENING STORMS SHOULD FORM OVER WESTERN NEBRASKA...THEN MOVE
SOUTHEAST ACROSS SOUTH CENTRAL NEBRASKA AND NORTH CENTRAL KANSAS
TONIGHT.  THIS WILL POSE THE THREAT OF A SQUALL LINE WITH DAMAGING
WINDS AFTER DARK.

FINALLY...RAINFALL AMOUNTS MAY EXCEED 2 INCHES IN SOME AREAS...AND
CAUSE CONCERNS ABOUT FLOODING LATE TONIGHT.

EMERGENCY MANAGERS...SPOTTER GROUPS...AND RESIDENTS SHOULD
CHECK THE WEATHER THROUGHOUT THE DAY FOR THE LATEST UPDATES.

DDN

KSZ005>007-017>019-NEZ039>041-046>049-060>064-072>077-082>087-280300-

SEVERE WEATHER OUTLOOK - SOUTH CENTRAL NEBRASKA/NORTH CENTRAL KANSAS
NATIONAL WEATHER SERVICE HASTINGS NE
538 PM CDT THU JUL 27 2000

...SPOTTER ACTIVATION MAY STILL BE NEEDED TONIGHT...

COUNTIES WITH THE BEST THREAT OF WIDESPREAD SEVERE WEATHER TONIGHT
ARE THOSE SOUTH OF A LINE FROM LOUP CITY...TO GRAND ISLAND...TO
GENEVA OF FILLMORE COUNTY.  THE PRIMARY SEVERE THREAT FOR THESE
COUNTIES WILL BE FROM DAMAGING STRAIGHT LINE WIND...AND WILL COME
AFTER 10 PM.

MEANWHILE...THIS EVENING...THUNDERSTORMS FIRING ALONG A STATIONARY
BOUNDARY NEAR THE KANSAS...NEBRASKA BORDER COULD REACH SEVERE LIMITS
OVER NORTH CENTRAL KANSAS.  THE PRIMARY THREAT IS EXPECTED TO BE
ISOLATED...AND WILL COME FROM LARGE HAIL AND DAMAGING DOWN-BURST
WIND...HOWEVER...TORNADOES ARE CERTAINLY POSSIBLE DUE TO WIND SHEAR
ALONG THE BOUNDARY.

WIDELY SCATTERED THUNDERSTORMS OVER SOUTH CENTRAL NEBRASKA THIS
EVENING ARE NOT EXPECTED TO REACH SEVERE LIMITS.

LATER...THUNDERSTORMS MOVING INTO THE NEBRASKA PANHANDLE WITH AN
UPPER DISTURBANCE THIS EVENING ARE EXPECTED TO CONTINUE AN EAST...
SOUTHEASTWARD TRACK INTO SOUTH CENTRAL NEBRASKA AND NORTH
CENTRAL KANSAS.

FINALLY...RAINFALL AMOUNTS MAY EXCEED 2 INCHES IN SOME AREAS...AND
COULD CAUSE FLOODING PROBLEMS LATE TONIGHT.

EMERGENCY MANAGERS...SPOTTER GROUPS...AND RESIDENTS SHOULD CONTINUE
TO MONITOR THIS DEVELOPING SITUATION THIS EVENING...AND BE PREPARED
PLAN ALTERATIONS OR SPOTTER ACTIVATION.

09