Severe Thunderstorm Warning 81, NWS North Platte, NE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
204 PM CDT SAT JUN 3 2000

...CHALLENGE CONTINUES TO BE THUNDERSTORM POPS TONIGHT...

ZONAL FLOW ACROSS THE U.S. WITH ONLY ONE WAVE OF SIGNIFICANCE ALONG
THE U.S./CANADIAN BORDER IN THE VICINITY OF MT. AT THE SURFACE...
LOW PRESSURE IS CENTERED OVER THE NORTHWEST PANHANDLE OF NEBRASKA
WITH A WARM FRONT ACROSS SOUTHERN SD...A DRYLINE THROUGH THE
SOUTHERN PANHANDLE AND EASTERN COLORADO...AND A COLD FRONT THROUGH
CENTRAL WYOMING.

NOTED NO SIGNIFICANT DIFFERENCES AMONG THE MODELS FOR THIS FORECAST.

AFOREMENTIONED SHORTWAVE IS FORECAST TO MOVE QUICKLY EAST/SOUTHEAST
THROUGH THE DAKOTAS OVERNIGHT. DECENT H7 VMAX CURRENTLY MOVING
ACROSS SD WITH CONVECTION EXPECTED TO CONTINUE EAST AND BYPASS THE
AREA. MODELS DO SUGGEST ANOTHER WAVE WILL DROP THROUGH EASTERN
WY/NEBRASKA PANHANDLE AND CROSS SOUTHWESTERN NEBRASKA INTERSECTING
THE SURFACE FRONT IN THE AREA BY 06Z. CAPES/LAPSE RATES AND LOW
LEVEL MOISTURE ARE SUFFICIENT TO SUPPORT CONVECTION. IF STRONG CAP
OVER THE AREA WEAKENS THIS FEATURE MAY HAVE ENOUGH FORCING TO
INITIATE CONVECTION LATE THIS AFTERNOON OR EVENING ALONG THE SURFACE
BOUNDARY. BREEZY CONDITIONS ARE LIKELY TO PERSIST EAST OF THE
BOUNDARY TONIGHT...WINDS WILL SLOW DUE TO CONVERGENCE ALONG AND NEAR
THE BOUNDARY THEN SHIFT TO THE NORTH. SHOULD BE NORTHERLY ALREADY
THIS EVENING IN THE NORTHWEST PART OF CWA.

EXPECT FRONT TO BE SOUTH OF THE CWA BY SUNRISE SUNDAY. DIVERGENT
LAYER Q-VECS SUGGEST STRONGLY SUBSIDENT ENVIRONMENT TO BUILD
SOUTHWARD FROM THE DAKOTAS IN WAKE OF FROPA. LOW LEVEL GRADIENTS
ARE FORECAST TO BE TIGHT WITH H85 WIND SPEEDS OF 20 TO 35 KNOTS
THROUGH 18Z TAPERING BACK TO 15 TO 25 KNOTS BY 00Z. THUS WINDY
WORDING WARRANTED FOR MUCH OF THE CWA AGAIN ON SUNDAY. THINK COOLER
AVN MOS LOOKS BETTER...MODELS RESOLVE LITTLE OR NO WARMING OF TEMPS
AT H85 DUE TO STRONG CAA IN UPSLOPE FLOW.

HIGH PRESSURE SHOULD BE DIRECTLY OVER THE AREA SUNDAY NIGHT WITH
MOST LOCATIONS DECOUPLING AND LIKELY COOLING BELOW MOS...SIMILAR TO
SCENARIO OF A FEW DAYS AGO. OTHERWISE NO CONCERNS WITH HIGH AND DRY
CONDITIONS PREVAILING.

MORE OF THE SAME INTO MONDAY. UPPER RIDGE WILL BEGIN BUILDING EAST
FROM THE ROCKIES INTO THE PLAINS AND THE SURFACE HIGH WILL BE EAST
OF THE AREA WITH RETURN SOUTH/SOUTHEAST FLOW INCREASING. SHOULD
STILL BE A DRY AND STABLE ENVIRONMENT WITH NO CONCERNS. SOME LOW
LEVEL WAA INDICATED ON AVN BUT WARMING MAY BE TEMPERED SOME BY
SOUTHEAST WINDS.

IN THE EXTENDED...RIDGE EXPECTED TO PERSIST OVER THE AREA THROUGH
THE MIDDLE PART OF THE WEEK. NO SIGNIFICANT WAVES FORECAST TO COME
THROUGH THE RIDGE UNTIL THURSDAY AT THE EARLIEST. WILL ONLY MENTION
A CHANCE IN THE WEST THURSDAY WHERE THE MRF DEVELOPS A LEE TROF AND
HINTS AT A WEAK WAVE IN WY/CO.

.LBF...NONE

DJB