Severe Thunderstorm Warning 112, NWS Hastings, NE

SOUTH CENTRAL NEBRASKA/NORTH CENTRAL KANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
227 PM CDT THU JUL 20 2000

TSTM CHCS/TIMING REMAIN THE PROBLEM

A COUPLE OF SFC BOUNDARIES TO NOTE ACROSS THE AREA THIS AFTN...ONE
OF WHICH EXTENDS FROM BETWEEN KCDR/KAIA TO KODX TO KTQE.  THE SECOND
BOUNDARY STRETCHES ALONG I-70 IN NORTHERN KANSAS.  OVERALL FLOW
WEST/NORTHWEST WITH SEVERAL EMBEDDED SHORTWAVE TROFS.  THE NEXT WAVE
OF CONSEQUENCE CURRENTLY LOCATED IN SOUTHWEST SOUTH DAKOTA AND THIS
WAVE WILL MOVE SOUTHEAST THRU CWA THIS EVENING.  SCATTERED SHOWERS
AND THUNDERSTORMS HAVE ALREADY DEVELOPED NR AFOREMENTIONED
BOUNDARIES AND COVERAGE SHLD INCREASE THIS REMAINDER OF AFTN/EVE AS
WAVE ADVANCES.  LAPS DATA INDICATES CAPES OF 1500 J/KG AND WEAK CAP
IN WESTERN/SOUTHERN CWA WHICH IS INCLUDED IN SPC DY1 SLGHT
RISK...AND SPC DISCUSSION DETAILS SVR POTENTIAL.  ZONE WORDING FOR
TONIGHT WILL BE WORDED AS SCT TSTMS.  ADDITIONAL TSTMS TONIGHT IN
EASTERN CO WILL ALSO BE OF CONCERN FOR SOUTHERN COUNTIES AS
CONVECTION ORGANIZES INTO MCS AND MOVES E/SE INTO CWA LATE.

BEYOND TONIGHT...MODELS HAVE HAD DIFFICULTY TIMING AND DETERMING
EFFECT OF WAVES IN THIS W/NW FLOW REGIME...HOWEVER UNTIL WESTERN US
RIDGE BUILDS FURTHER EAST OVER THE WEEKEND...SOME CHC FOR TSTMS
REMAINS.  FOLLOWED CLOSER TO ETA/MESOETA SOLUTIONS FOR FORECAST.
BOUNDARIES ARE PUSHED SOUTH INTO SOUTHERN KS/OKLAHOMA FROM
CONVECTION TONIGHT.  HIGH PRESSURE BUILDS SOUTH AND EAST FROM
DAKOTAS WITH WEAK RETURN FLOW SETTING UP.  THIS WILL PROVIDE AN
INCREASE IN MOISTURE TO ALREADY JUICY ATMOSPHERE.  MODEL TIMING OF
NEXT WAVE DIVING S THROUGH WESTERN NEBRASKA OCCURS FRIDAY NIGHT TIME
FRAME...HOWEVER CANNOT RULE AT THE POSSIBILITY OF SCT STORMS DURING
THE DAY.  MODELS/SPC DY2 OUTLOOK KEY IN ON MCS DEVELOPING IN
SOUTHWEST NEBRASKA FRIDAY NIGHT AND TRACKING S/SE.  WILL PLACE
HIGHEST POPS IN SOUTHWEST/WESTERN COUNTIES.

SATURDAY SHLD SEE A FAIR AMNT OF SUNSHINE AND WILL DOWNPLAY TSTM
CHCS WITH THE IDEA THAT TIMING SHLD BE LATE.  AS FAR AS TEMPS...WILL
NOT DEVIATE MUCH FROM GUIDANCE.

IN THE EXTENDED...WILL KEEP TSTM CHCS IN FCST SAT NIGHT/SUNDAY
BEFORE RIDGE BUILDS EAST.  DRY MONDAY...BUT TSTM CHCS MAY RETURN AS
EARLY AS MONDAY NIGHT AS PACIFIC NORTHWEST SYSTEM APPROACHES AND
FLATTENS RIDGE.  FOR NOW WILL RETURN TSTM CHCS TO FCST TUESDAY.

.GID...NONE.

FAY

KSZ005>007-017>019-NEZ039>041-046>049-060>064-072>077-082>087-202100-

SEVERE WEATHER OUTLOOK - SOUTH CENTRAL NEBRASKA/NORTH CENTRAL KANSAS
NATIONAL WEATHER SERVICE HASTINGS NE
1115 AM CDT THU JUL 20 2000

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

A SURFACE FRONT EXTENDING FROM IMPERIAL EAST TO HOLDREGE AND BEATRICE
WILL BE THE FOCUS FOR SCATTERED SHOWERS AND THUNDERSTORMS ONCE AGAIN
TODAY. THE ATMOSPHERE ALONG AND SOUTH OF THIS BOUNDARY WILL BECOME
MODERATELY UNSTABLE BY EARLY THIS AFTERNOON. IT IS IN THE UNSTABLE
AREA THAT THE BEST CHANCE OF SEVERE WEATHER WILL BE.

AS AN UPPER LEVEL DISTURBANCE TRACKS EAST OUT OF WYOMING THIS
AFTERNOON...SCATTERED THUNDERSTORMS WILL INCREASE ACROSS THE ENTIRE
AREA. HOWEVER...THUNDERSTORMS WILL LIKELY BE MOST NUMEROUS FROM
EXTREME SOUTHERN NEBRASKA INTO KANSAS WHERE THERE WILL BE THE
POTENTIAjL FOR LARGE HAIL AND DAMAGING WIND WITH SOME OF THE STORMS.

GURNEY