Severe Thunderstorm Warning 48, NWS North Platte, NE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
304 AM CDT THU JUN 7 2001

...FORECAST CHALLENGE WILL BE CHANCE OF THUNDERSTORMS...

ISOLATED THUNDERSTORMS CONTINUE TO FORM IN CONVERGENT FLOW OVER
EXTREME SOUTHWEST FORECAST AREA AT 07Z. H2 DIVERGENCE ALOFT AIDING
LIFT FOR DEVELOPMENT WITH FORCING TO BE ENHANCED AS DAYBREAK
ARRIVES WITH H5 WAVE TO MOVE EAST. 06Z HAND SURFACE ANALYSIS SHOWED
SEMI STATIONARY FRONT SNAKING ALONG THE EASTERN SLOPES OF THE
MOUNTAIN STATES...WHILE HIGH PRESSURE WAS RIDGING SOUTHEAST ALONG
THE WESTERN PLAINS. DEWPOINTS ARE INTO THE 50S WITH MID 60S IN THE
SOUTHWEST. STRATUS DECK SPREADING SLOWLY WEST NORTHWEST WITH LOW
CLOUDS TO EXPAND NORTHWEST FOR THE MORNING.

MODELS IN GENERAL AGREEMENT WITH LITTLE CHANGE TODAY WITH UPSLOPE
FLOW TO KEEP A STEADY STATE OF MOISTURE IN PLACE FOR FUEL FOR
THUNDERSTORMS IN THE WEST. ETA MOST CONSISTENT AND FOLLOWED THROUGH
60 HOURS THEN AVN BEYOND.

THIS MORNING THERE WILL BE EXTENSIVE LOW CLOUDS EARLY IN THE
SOUTHWEST WITH AREAS OF FOG. ISOLATED THUNDERSTORMS TO CONTINUE WITH
ZONES BREAKOUT FOR EACH. THE UPSLOPE CONVERGENT FLOW CONTINUES
TODAY WITH SHOWERS AND THUNDERSTORMS TO REFORM BY LATE DAY WITH
EXISTING BOUNDARIES TO BE THE FOCUS WITH BEST CHANCE FOR STORMS TO
BE IN THE SOUTHWEST. TEMPERATURES WILL BE HELD DOWN BY CLOUD
COVERAGE EARLY THEN RECOVER IN THE SOUTHWEST FOR TEMPERATURES CLOSE
TO GUIDANCE.

TONIGHT THE SURFACE HIGH WEAKENS AND BUILDS SOUTH WHICH WILL
REALIGN FOCUS FOR CONVECTION FURTHER TO THE SOUTH AFTER MIDNIGHT AS
SURFACE WINDS TURN TO THE SOUTH. GUIDANCE TEMPERATURES APPEAR TO LOW
CONSIDERING MOISTURE AND DEWPOINTS FORECASTED AND WILL UP A CATEGORY
IN THE SOUTHWEST. BOUNDARY LAYER MOISTURE WILL REMAIN PRESENT FOR
LOW CLOUDS AND AREAS OF FOG TO REFORM OVERNIGHT.

FRIDAY THE H5 RIDGE AXIS BUILDS EAST WITH SUBSIDENCE TO INCREASE
ACROSS THE WEST. AREAS OF LOW CLOUDS SHOULD GIVE WAY TO PARTLY
SUNNY SKIES. 850-700 MB LAYER LAPSE RATES INCREASE BUT WITH
INCREASING SUBSIDENCE ALOFT WILL REMOVE LOW POPS EXCEPT FOR THE
EXTREME WESTERN COUNTIES WHERE A STORM COULD PROPAGATE INTO FRIDAY
NIGHT. TEMPERATURES WILL RISE SLOWLY TO AROUND 80 WITH EARLY MORNING
LOW CLOUDS TO SLOW BURN OFF.

IN THE EXTENDED THE H5 RIDGE AXIS BUILDS EAST THROUGH SUNDAY WITH
LEESIDE LOW TO DEVELOP AND MOVE EAST. RIDGE RUNNERS WILL BRING AN
INCREASE IN MID AND HIGH LEVEL CLOUD COVERAGE. YET WITH THE GULF
RETURN MINIMIZED TO THE WESTERN HIGH PLAINS A MAINLY DRY FORECAST
SHOULD HOLD FOR THE WEEKEND. THEN MONDAY AS A STRONGER PUSH OCCURS
A CHANCE OF THUNDERSTORMS MONDAY THEN AGAIN LATE TUESDAY AS BACK
DOOR COLD FRONT MOVES SOUTH. WEDNESDAY THE FRONT WILL BE TO THE
SOUTH WITH HIGH PRESSURE BUILDS IN FROM THE NORTHWEST WITH MAINLY
DRY CONDITIONS WEDNESDAY.

.LBF...NONE.

KECK

NEZ004>010-022>029-035>038-056>059-069>071-071630-

SEVERE WEATHER OUTLOOK FOR WESTERN AND NORTH CENTRAL NEBRASKA
NATIONAL WEATHER SERVICE NORTH PLATTE NE
458 AM CDT THU JUN 7 2001

...STORM SPOTTER ACTIVATION MAY BE NEEDED TODAY AND TONIGHT...

STORM SPOTTER ACTIVATION MAY BE NECESSARY TODAY AND TONIGHT ACROSS
PORTIONS OF WESTERN NEBRASKA. THE AREA OF GREATEST RISK IS WEST OF A
HAYES CENTER...TO ARTHUR...TO ANTIOCH LINE.

MOIST UNSTABLE AIR WILL CONTINUE TO POOL ACROSS WESTERN PORTIONS OF
THE OUTLOOK AREA TODAY. BY LATER THIS AFTERNOON...A VIGOROUS UPPER
LEVEL DISTURBANCE WILL INTERACT WITH THE UNSTABLE AIR CAUSING
EXPLOSIVE DEVELOPMENT OF THUNDERSTORMS. AT THIS TIME THE MAIN SEVERE
WEATHER THREAT WILL BE LARGE HAIL AND DAMAGING WINDS.

CLB

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORTH PLATTE, NE
635 AM CDT THU JUN 7 2001

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0617 AM    12 NW OGALLALA            NE   .88 INCH HAIL
06/07/01   KEITH
TLK