Severe Thunderstorm Warning 163, NWS North Platte, NE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
225 PM CDT TUE JUL 1 2003

...TEMPERATURES IN THE NEAR TERM AND PRECIP CHANCES FROM THURSDAY
NIGHT THROUGH THE WEEKEND MAIN CHALLENGES...

UPPR PATTERN THIS AM CONTINUES TO BE HIGHLIGHTED MAINLY BY RIDGING
OVER THE CENTER OF THE CONUS...THE REMNANTS OF TS BILL OVR THE LWR
MS VALLEY AND AN UPPER LEVEL LOW ENTERING THE WRN COAST OF CANADA.
AT THE SFC...WEAK HIGH HAS MOVED FROM ERN NEBR INTO ERN IA TODAY
WITH A DEEPENING SFC TROF EXTENDING FROM WRN ND TO NERN COLORADO.
DECENT GRADIENT IN BETWEEN WITH WINDS IN THE BREEZY CATEGORY ACROSS
MOST OF THE FA ATTM.

.TONIGHT...THE ETA THIS AM SEEMED TO INITIALIZE A TAD TOO WARM
COMPARED TO THE LBF SOUNDING AT H7. WITH A DECENT SFC BOUNDARY...GOOD
LOW LEVEL CONVERGENCE AND DEW POINTS IN THE MID 60S...UPDATED PVS
FCST FOR ISOLATED SHRAS/TSRAS IN THE WRN AND NWRN ZONES. WIL END
THIS AROUND 9 PM AS INSTABILITY SHOULD DECREASE WITH SURFACE
COOLING.

.TOMORROW AND TOMORROW NIGHT...ALOFT...H7 TEMPS CONTINUE TO WARM AS
RIDGE BUILDS INTO THE FA. SFC LOW OVR WRN SD WILL PROGRESS EWD
TOMORROW DRAGGING SFC TROF EAST. EVEN WITH H7 TEMPS FAIRLY WARM
TOMORROW...MODELS INDICATING A STRONG DRYLINE SURGE DURING THE AFTN.
WITH CAPES IN EXCESS OF 3000J/KG AND CIN INDICATING ONLY A MARGINAL
CAP JUST EAST OF THE DRY LINE...THINK AN ISOLATED MENTION OF TSRAS
IS IN ORDER. WILL CONFINE THIS TO THE FAR NRN ZONES AND EXTEND THIS
SOUTH AS FAR AS HIGHWAY 2. SHOULD SEE ACTIVITY END QUICKLY AFTR
SUNSET WITH LIMITED DYNAMICS. AS FOR TEMPS...WILL GO WITH WARMEST
ACROSS THE NRN AND WRN ZONES...WITH BEST WRLY COMPONENT AND BEST
COMPRESSIONAL WARMING ALONG SFC TROF.

.THURSDAY AND THURSDAY NIGHT...WEAK SFC BOUNDARY SETS UP ACROSS THE
FA ON THURSDAY AS EVIDENCED FROM FCSTED LL WIND FIELD. WITH UPPR
FLOW BECOMING MORE ZONAL...H7 TEMPS BEGIN TO COOL TOWARD 10C WITH H5
TEMPS COOLING A TAD ALSO BY AFTN. HIGH RES ETA INDICATING ANOTHER
ROUND OF CAPES IN EXCESS OF 3000 J/KG THURS AFTN WITH ONLY A
MARGINAL CAP. AT THIS JUNCTURE...AM CONSIDERING LOW POPS ACROSS THE
ERN HALF OF THE FA. WILL DEFINE PRECIP LINES ALONG ISC GRIDS.

.FRIDAY WILL BE SOMEWHAT COOLER WITH SFC FRONT PUSHING THROUGH FA
BEFORE STALLING ACROSS NRN KS. ONGOING PRECIP FCST IN GOOD SHAPE
WITH POPS ACROSS THE BOARD...HOWEVER WILL PROBABLY SHAVE THESE BACK
IN THE NW GIVEN FRONTAL BOUNDARY AND BEST MOISTURE LOCATED OVER ERN
AND CENTRAL NEBR.

.SATURDAY THROUGH TUESDAY...RIDGE BEGINS TO FLATTEN AND CAP STRENGTH
ERODES FURTHER LATE ON FRIDAY AS AN UPPER LEVEL TROF TRAVERSES
SRN CANADA. WITH WEAK SFC BOUNDARY ACROSS THE AREA AND SEVERAL
EMBEDDED SHORT WAVES MOVING QUICKLY EAST IN THE ZONAL
FLOW...CONTINUATION OF LOW POPS WILL BE IN ORDER SATURDAY THROUGH
SUN NIGHT. WILL LEAVE MOST OF MONDAY AND ALL OF TUESDAY DRY AS UPPR HIGH
BUILDS INTO THE CENTRAL ROCKIES ONCE AGAIN.

.LBF...NONE.

CLB

NEZ004>010-022>029-035>038-056>059-069>071-094-021000-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NORTH PLATTE NE
345 PM CDT TUE JUL 1 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN AND NORTH CENTRAL
NEBRASKA.

.DAY ONE...TONIGHT

ISOLATED THUNDERSTORMS WILL BE POSSIBLE WEST OF A LINE FROM
AINSWORTH TO OGALLALA THROUGH LATE EVENING. A LACK OF DEEP MOISTURE
FOR THE STORMS TO WORK WITH WILL LIMIT THE COVERAGE OF ANY STORMS
THAT DEVELOP IN THIS AREA. HOWEVER...ANY STORMS THAT DEVELOP WILL
HAVE THE POTENTIAL TO PRODUCE BRIEF...BUT DAMAGING WIND GUSTS AND
LARGE HAIL THROUGH LATE EVENING. THE BEST CHANCE FOR SEVERE
THUNDERSTORMS WILL BE PRIMARILY WEST OF A LINE FROM VALENTINE TO BIG
SPRINGS. MOST OF THE OUTLOOK AREA WILL REMAIN DRY HOWEVER.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

AN AREA OF LOW PRESSURE WILL EXTEND FROM NEAR VALENTINE TO BIG
SPRINGS BY LATE WEDNESDAY AFTERNOON. THE AIRMASS AHEAD OF THIS
FEATURE WILL BE QUITE UNSTABLE...BUT WILL ALSO BE WARM ALOFT. WHILE
THIS WILL LIMIT COVERAGE OF THUNDERSTORMS WEDNESDAY AFTERNOON AND
WEDNESDAY NIGHT...ANY STORMS THAT ARE ABLE TO DEVELOP WILL HAVE THE
POTENTIAL TO PRODUCE SEVERE WEATHER. THE BEST POTENTIAL FOR SEVERE
THUNDERSTORM DEVELOPMENT WILL BE IN AN AREA NORTH OF A LINE FROM
VALENTINE TO DUNNING.

A COLD FRONT WILL ALSO MOVE ACROSS THE STATE WEDNESDAY NIGHT AND
STALL ACROSS THE AREA THURSDAY. THIS WILL BRING A CONTINUED CHANCE
FOR THUNDERSTORMS THURSDAY AFTERNOON AND NIGHT OVER MAINLY THE
NORTHERN PORTIONS OF THE OUTLOOK AREA.

THUNDERSTORM CHANCES WILL REMAIN ACROSS THE AREA INTO THE WEEKEND.
HIGH PRESSURE ALOFT IS THEN EXPECTED TO BUILD INTO THE OUTLOOK AREA
ONCE AGAIN FOR THE FIRST PART OF NEXT WEEK WHICH WILL LIMIT
PRECIPITATION CHANCES.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED TONIGHT...BUT MAY BE NEEDED
LATE WEDNESDAY AFTERNOON AND EVENING ACROSS THE NORTHERN PORTION OF
THE OUTLOOK AREA.

JWS