Severe Thunderstorm Warning 172, NWS Hastings, NE

CENTRAL NEBRASKA/NORTH CENTRAL KANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
226 PM CDT SUN AUG 4 1996

SEVERE WEATHER THREAT TONIGHT OF IMMEDIATE CONCERN.

KUEX 88D WITH THUNDERSTORMS REPEATING OVER SAME AREA FROM LXN TO
GREELEY.  NEXT TRIGGER MECHANISM APPEARS TO LINE OF RETURN FROM LBF TO
MCK.  THIS ALSO SEEN ON 1KM VIS SHOT.  THUNDERSTORMS EXPECTED TO
INCREASE OVER NEBRASKA CWA BY LATE AFTERNOON.  WIND PROFILE AND HIGH
INSTABILITY MAY SUPPORT ISOLATED SUPERCELLS.  WILL LIKELY MENTION
POSSIBLE OF SEVERE IN NORTH CENTRAL ZONES TONIGHT WITH CYCLOGENISIS IN
NORTHWEST KANSAS STRENGTHENING SFC MOISTURE CONVERG.

VERY QUICK LOOK AT MODELS...ONLY AVN/ETA GRIDS...GIVES THIS
INTERPRETATION.  BOTH AVN/ETA GRIDDED DATA MOVE H7 WAV FROM COLORADO UP
INTO CWA BY TONIGHT.  FINE UPPER DIVERGENCE IN RR QUAD OF JET FROM
NORTH CENTRAL NEBRASKA TO NORTH DAKOTA.  THE COMBINATION OF FAVORALBE
JET DYNAMICS AND WAVE MAY QUICK MORE INTENSE STORMS TOWARD MIDNIGHT.
THIS COULD VERY WELL BE THE BEGINNING OF THE TALKED ABOUT MCS MOVING
INTO IOWA REGION.

FRONT NEVER REALLY COMES ON THROUGH AS UPPER FLOW LEAVES LITTLE TO PUSH
IT.  ACTUALLY...ANOTHER COLD POOL OF -25C H5 AIR OVER BRITISH COLUMBIA
ATTM WILL DIVE INTO BACK SIDE OF TROF.  EXPECT THIS TO ACTUALLY BE COLD
PUSH...AS LEAD FRONT WILL WASH OUT...RETREAT OR WHAT HAVE YOU.  THE
SECOND FRONT LOOKS LIKE IT MAY WORK IN HERE TUESDAY...FURTHER NORTH
WILL HAVE BEST DYNAMICS AT FIRST GLANCE.

GUIDANCE WISE...WENT A BIT WARMER THAN PREVIOUS FORECAST GIVING SLOWING
FRONT.  WILL BE VERY WARM AND HUMID SOUTH TONIGHT.  PER CALL WITH TOP
WILL HIGHLIGHT THIS.  AMOUNT OF SUNSHINE NORTH TOMORROW STILL IN
QUESTION AND WILL PLAY LROLE IN TEMPS.  LIKE THE FWC POPS BETTER.

GRI 070/088 63             HBR 071/091 63
ODX 068/086 73             BEL 073/094 43
LXN 066/084 62

MORITZ

KSZ005>007-017>019-NEZ039>041-046>049-060>064-072>077-082>087-050500-

SEVERE WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE HASTINGS NE
329 PM CDT SUN AUG 4 1996

...SEVERE WEATHER OUTLOOK FOR SOUTH CENTRAL NEBRASKA AND FOR A PART
   OF NORTH CENTRAL KANSAS...

SPOTTER ACTION...IT IS EXPECTED SPOTTER ACTIVATION WILL BE NEEDED
ACROSS THE AREA LATE THIS AFTERNOON OR TONIGHT.

SYNOPSIS...

THERE IS THE POTENTIAL FOR SEVERE THUNDERSTORMS TO DEVELOP LATE THIS
AFTERNOON AND TONIGHT ACROSS SOUTH CENTRAL NEBARSKA AND NORTH CENTRAL
KANSAS.

AT 315 PM...A TORNADO WATCH WAS IN EFFECT FOR NEARLY ALL OF SOUTH
CENTRAL NEBRASKA UNTIL 800 PM.

TEMPERATURES IN THE UPPER 80S TO LOWER 90S...AND SURFACE DEWPOINTS IN
THE LOWER 70S HAVE COMBINED TO FORM A VERY UNSTABLE AIRMASS OVER THE
REGION.  ONE AREA OF THUNDERSTORMS WILL CONTINUE THE REST OF THE
AFTERNOON NORTH AND WEST OF A LINE FROM CENTRAL CITY NEBRASKA TO
PHILLIPSBURG KANSAS.  A FEW OF THESE THUNDERSTORMS MAY BECOME SEVERE AS
THEY MOVE QUICKLY NORTHEAST.  THUNDERSTORMS SOUTH AND EAST OF THAT LINE
WILL LIKELY OCCUR AFTER 500 PM.

BY THIS EVENING...A STRONG UPPER LEVEL DISTURBANCE WILL PUSH NORTH INTO
NORTH CENTRAL KANSAS AND SOUTH CENTRAL NEBRASKA.  THIS DISTURBANCE WILL
TEAM WITH INCREASING LIFT IN THE LOWER ATMOSPHERE AND TRIGGER NUMEROUS
THUNDERSTORMS.  WIND PROFILES AND THE HIGH INSTABILITY WILL HELP
PRODUCE AN ENVIRONMENT FAVORABLE FOR SEVERE THUNDERSTORMS...SOME OF
WHICH WILL PRODUCE LARGE HAIL...DAMAGING WINDS AND POSSIBLY TORNADOES.

EVEN THOUGH THE INITIAL TORNADO WATCH IS IN EFFECT UNTIL 800 PM IN
SOUTH CENTRAL NEBRASKA...THERE IS THE POSSIBILITY FOR SEVERE WEATHER
TO CONTINUE INTO THE NIGHT OVER THE AREA. ( ALL INTERESTED PARTIES
SHOULD CONTINUE TO MONITOR THIS POTENT WEATHER SITUATION BE PREPARED TO
TAKE ACTION.  LISTEN TO LOCAL MEDIA OR NATIONAL WEATHER SERVICE RADIO
FOR THE LATEST STATEMENTS AND FORECASTS.

MORITZ