Severe Thunderstorm Warning 174, NWS Hastings, NE

SOUTH CENTRAL NEBRASKA/NORTH CENTRAL KANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
2OO PM CST SUN NOV 5 2000

MAJOR CHANGES ON THE WAY...AND THE MAIN CONCERN IS WHETHER COLD AIR
WILL FUNNEL QUICKLY ENOUGH INTO THE CWA TO ALLOW FOR MEASURABLE
SNOWFALL TONIGHT AND EARLY MONDAY MORNING BEFORE THE SYSTEM PULLS
NORTHEAST AND TAKES THE MOISTURE WITH IT. THE BIG PICTURE ON WV SATL
PIX SHOWS AN UPPER LEVEL TROF DIGGING OVER THE NORTHERN ROCKIES
SOUTHWARD TOWARDS NEW MEXICO WITH A SERIES OF WAVES ROTATING AROUND
THE MAIN BODY. AT THE SURFACE A BROAD AREA OF LOW PRESSURE EXTENDS
FROM THE NORTHERN PLAINS INTO THE CENTRAL AND SOUTHERN HIGH PLAINS.
3MB+ PRESSURE CHANGES OVER THE LAST 3HRS WAS NOTED JUST AHEAD OF
BROAD LOW PRESSURE WITH MOISTURE AXIS RUNNING THROUGH EASTERN KANSAS
AND EASTERN NEB. DO POINTS IN THESE AREAS WERE GENERALLY IN THE
50S WITH A FEW 60S. LOW LEVEL MOISTURE CONTINUES TO STREAM NORTHWARD
IN STRONG SOUTHERLY FLOW. SOMEWHAT UNSTABLE IN THE REGION AS LOW
CLOUDS BEGINNING TO BREAK UP A BIT. LIS ARE APPROACHING -4 OVER
PORTIONS OF KANSAS WHERE MORE SUN IS GETTING IN.

ALL 3 SHORT RANGE MODELS DID A DECENT JOB INITIALIZING VORT ENERGY
OVER NORTHEAST UTAH AS WELL AS SOUTHERN STREAM ENERGY JUST SOUTH OF
THE U.S. BORDER. MOVING AHEAD 6HRS TO 05/18Z INDICATES ALL THE
MODELS HAVE A DECENT GRIP ON THE SITUATION AS COMPARED TO/VERIFIED BY
WV SAT PIX. A GLANCE AT TIME SERIES AGAIN SUGGESTS THAT THE 3 SHORT
TERM MODELS ARE IN HARMONY WRT THE FROPA LATER TONIGHT.

TONIGHT...AS MENTION...STRONG CAA TO PLUNGE THROUGH THE CWA
OVERNIGHT. THE MODELS SUGGEST THE FRONT REACHING GRI SOMETIME
AROUND MIDNIGHT WITH WINDS SHIFTING TO THE NORTHWEST. BY THAT TIME
SFC LOW PRESSURE SHOULD BE MORE ORGANIZED OVER KANSAS AS THE UPPER
LEVEL TROF BEGINS TO SWING OUT INTO THE PLAINS. A LOOK AT CROSS
SECTIONS OVER THE CWA SUGGEST THAT THERE IS SOME CONVECTIVE
INSTABILITY OVER OUR KANSAS COUNTIES AND SOMEWHAT INTO OUR NEBRASKA
COUNTIES. THIS CONCURS WITH SPCS SWODY1 SLGT RISK ENCROACHMENT INTO
PARTS OF OUR CWA. THEREFORE MENTION OF THUNDERSTORMS SOUTH TONIGHT
WARRANTED. PCPN WILL BEGIN AS RAIN AND EVENTUALLY MIX WITH SNOW
TOWARDS DAWN. BUT BY THE TIME ENOUGH COLD AIR MOVES IN...MOST OF
THE SIGNIFICANT PCPN SHOULD BE TAPERING OFF. SO NO SIGNIFICANT
ACCUMULATIONS ARE EXPECTED WITHIN THE CWA.

MONDAY...SOME LIGHT SNOW SHOULD LINGER THROUGH THE EARLY MORNING
HOURS TO THE NORTH WITH LIQUID FOUND SOUTH. IN SPITE OF COPIOUS
MOISTURE...DYNAMIC/ISENTROPIC LIFT WILL BE FOUND EAST OF THE CWA...
SO WILL WORD FOR MAINLY A MORNING EVENT. WIND WILL ALSO BE A
FACTOR OVER THE AREA. THE PRESSURE GRADIENT TIGHTENS UP NICELY AND
SHOULD CATAPULT WINDS TO THE 20-30MPH RANGE WITH HIGHER GUSTS.
OVERALL...A PRETTY DREARY DAY IN STORE. TEMPS SHOULD MODERATE AND
BEGIN TO FALL FROM THE LOWER 30S INTO THE MID TO UPPER 20S OVER
NORTHERN SECTIONS OF THE CWA...WHILE TEMPS SOUTH REMAIN STEADY.

MONDAY NIGHT AND TUESDAY....CLOUDS HANG ON THRU PERIODS 3 AND 4 FOR
THE MOST PART. AT THIS POINT...CANT DISCOUNT SOME RAP AROUND SNOWS
MAINLY NORTH AND CENTRAL. SO WILL ADD SMALL POPS TO COVER. THE ETA
SUGGESTS A PARTIAL BREAKUP OF CLOUDS OVER OUR SOUTHERN CWA TUESDAY
AS THE SFC LOW TREKS NORTHEAST INTO MIN. WILL THEREFORE WORD FOR
PARTLY SUNNY IN KS COUNTIES FOR TUESDAY. NOT MUCH REBOUND IN TEMPS
AS STRONG NW FLOW CONTINUES CAA TREND.

IN THE EXTENDED...NO CHANGE TO WED AND THUR AND WILL GO DRY ON
FRIDAY.

.GID...NONE.

DEE

KSZ005>007-017>019-NEZ039>041-046>049-060>064-072>077-082>087-052300-

SEVERE WEATHER OUTLOOK - SOUTH CENTRAL NEBRASKA/NORTH CENTRAL KANSAS
NATIONAL WEATHER SERVICE HASTINGS NE
1200 PM CST SUN NOV 5 2000

...SPOTTER ACTIVATION MAY BE NEEDED OVER PARTS OF THE AREA DURING THE
EVENING...

A STRONG COLD FRONT WILL MOVE FROM VALENTINE AND OGALLALA AT NOON TO
AROUND O'NEILL AND BROKEN BOW BY 6 PM. SCATTERED SHOWERS AND A FEW
THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THIS FRONT...MAINLY AFTER
3 PM THIS AFTERNOON.

AS THIS FRONT MOVES THROUGH THE AREA...SHOWERS AND THUNDERSTORMS WILL
BECOME MORE NUMEROUS THIS EVENING...ESPECIALLY FROM GRAND ISLAND AND
HASTINGS SOUTHEAST. ALTHOUGH MOST OF THE STORMS WILL REMAIN BELOW
SEVERE LIMITS...A FEW SEVERE STORMS...PRODUCING LARGE HAIL AND STRONG
WIND...WILL BE POSSIBLE.

THE BEST CHANCE FOR SEVERE WEATHER WILL BE OVER NORTH CENTRAL KANSAS.
HOWEVER...AN ISOLATED SEVERE STORM CANNOT BE RULED OUT AS FAR NORTH
AS GRAND ISLAND. THUNDERSTORMS WILL SHIFT EAST OF ENTIRE REGION BY
AROUND MIDNIGHT AS THE COLD FRONT PASSES INTO EASTERN NEBRASKA.

DEG