Severe Thunderstorm Warning 210, NWS North Platte, NE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
251 AM CDT MON JUL 23 2001

...POSITION OF FRONT AND ITS EFFECT ON TEMPS/PRECIP THE MAIN
CHALLENGES...

06Z SFC ANALYSIS SHOWS NUMEROUS BOUNDARIES DUE TO CONVECTION.
ACTUAL FRONT IS EASIER PICKED OUT BY SATELLITE/RADAR...AND BASED ON
KLNX TRENDS...FRONT IS NOW COMING INTO NRN CWA. PREFRONTAL TROF
EVIDENT ACROSS ERN SD INTO SW NEBR. OUTFLOW BOUNDARY FROM SD
COVECTION IS SLIDING SWD AND JUST PASSED THE PINE RIDGE AT 06Z.
ANOTHER BOUNDARY LIFTING NWWD BASED ON KLNX RADAR...AND WILL HAVE
TO WATCH WHEN IT HITS THE FRONT...HOWEVER A DECENT INVERSION IS IN
PLACE BASED ON THE FACT THAT KVTN HAS THUNDER IN ITS OB...WITH
CONVECTION CLOSE TO 100 MILES AWAY ATTM.

WON'T SPEND ALOT OF TIME WITH MODEL OF CHOICE...FRONT SEEMS TO BE
PUSHING SWD AS ETA HAS SUGGESTED OVER THE LAST COUPLE OF DAYS.
NEITHER THE AVN NOR THE ETA HAD THE PRECIP OVER SC NEB LAST NIGHT...
BUT THE FRONT WILL BE CLOSE TO ETA POSITION AT 09Z. ALSO LIKE THE
ETA CONVECTIVE SOLUTION TWD 48-60 HRS.

FRONT SHOULD BEGIN TO SLOW IN ITS PROGRESSION DURING THE DAYTIME
HOURS. WOULD EXPECT IT TO BE SOMEWHERE NEAR THE KS/NEB BORDER BY
LATE AFTERNOON. FAIRLY SIGNIFICANT SHORT WAVE TROF PROGGED TO ROUND
THE UPPER RIDGE BY LATE AFTERNOON AS WELL. THIS SHORT WAVE TROF
DEVELOPING CONVECTION OVER THE SRN ROCKIES ATTM. POPS THEREFORE IN
ORDER AS IN GOING FCST...THE TRICK IS TO PLACE THEM. MOST AREAS
SHOULD SEE RAIN...BUT ETA HAS TWO SEPARATE COMPLEX DEVELOPMENT
AREAS. CONVECTION ALONG/NEAR THE FRONT IN SRN ZONES WOULD BE THE
HEAVY RAIN/STRONG WIND PRODUCERS SINCE BEST DEEP MOISTURE WOULD BE
IN THIS LOCATION...AND MELTING LEVEL SHOULD COME DOWN A BIT FOR
SOME HAIL POTENTIAL. IN THE NORTHERN ZONES...COMPLEX SHOULD HAVE THE
BEST DEEP LAYER SHEAR AND THEREFORE WOULD BE MORE SUPERCELLULAR IN
NATURE AND GOOD POTENTIAL FOR HAIL WITH MUCH LOWER MELTING LEVEL.

FRONT SHOULD GET PUSHED FURTHER S INTO KS BY OUTFLOW FROM
CONVECTION TONIGHT...AND WOULD THEN EXPECT CONVECTION TO BE
CONCENTRATED ALONG THE HIGH PLAINS...AND SOUTH INTO WRN KS AS UPPER
RIDGE FLATTENS. CURRENT FCST HAS THIS THINKING REFLECTED AS WELL...
BUT WILL ADJUST POPS A LITTLE THINKING THAT CONEVCTION WILL STILL BE
IN NERN ZONES FROM PREV NIGHT...THEN HIGHER POPS S FOR THE EVENING.
LOW LEVEL JET THIS FAR NORTH IS WEAK AND SERLY...SO WILL INCLUDE POPS
BUT SVR LOOKS LESS LIKELY AT THIS POINT. FRONT BEGINS TO COME NORTH
ON WED...BUT FAITH IN THE MODELS IN A CONVECTIVE SITUATION BY THEN IS
LOW. CURRENT EXTENDED HAS THIS IN HAND AS WELL...SO NO MAJOR CHANGES
PLANNED TO EXTENDED.

.LBF...NONE.

JWS

NEZ004>010-022>029-035>038-056>059-069>071-231630-

SEVERE WEATHER OUTLOOK FOR WESTERN AND NORTH CENTRAL NEBRASKA
NATIONAL WEATHER SERVICE NORTH PLATTE NE
544 AM CDT MON JUL 23 2001

...STORM SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON THROUGH
TONIGHT...

THERE IS A SLIGHT CHANCE FOR WIDELY SCATTERED SEVERE THUNDERSTORMS
ACROSS PORTIONS OF WESTERN AND NORTH CENTRAL NEBRASKA THIS AFTERNOON
AND TONIGHT.

A COLD FRONT WILL MOVE INTO SOUTHERN PORTIONS OF THE OUTLOOK AREA BY
THIS AFTERNOON. THIS WILL ALLOW EASTERLY UPSLOPE WINDS NORTH OF
THE FRONT TO TRANSPORT MOISTURE INTO THE WESTERN HIGH PLAINS.
THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG AND NORTH OF THE FRONT AS
AN UPPER LEVEL DISTURBANCE MOVES OUT OF THE ROCKIES. SOME OF
THESE STORMS MAY BECOME SEVERE LATE THIS AFTERNOON ACROSS WESTERN
PORTIONS OF THE OUTLOOK AREA...WITH LARGE HAIL AND DAMAGING WIND
GUSTS THE PRIMARY THREATS. THESE STORMS ARE EXPECTED TO CONTINUE
MOVING EAST ACROSS THE REMAINDER OF THE OUTLOOK AREA OVERNIGHT...WITH
THE PRIMARY THREAT OF WIND GUSTS OVER 55 MPH.

DP