Severe Thunderstorm Warning 196, NWS North Platte, NE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
305 PM CDT SAT JUL 11 1998

FORECAST CHALLENGE REDEVELOPMENT OF STRATUS/FOG TONIGHT...

WATER VAPOR IMAGERY LOOP INDICATES ELONGATED 5H SHORTWAVE MOVING EAST
ACROSS THE THE PLAINS ATTM WITH WEAKER WAVE OVER NERN CO. SUBSIDENCE TO
INCREASE ALONG THE FOOTHILLS THIS EVENING WITH DRYLINE FORMING IN THE
WEST. AVN MODEL SLOWEST IN MOVING 5H SHORTWAVE EAST WITH ETA/AVN
COMBINATION USED WHILE NGM APPEARS TO SCOUR OUT MOISTURE IN THE WEST TO
FAST.

17Z SURFACE ANALYSIS SHOWED TROUGH AXIS EXTENDING FROM NEAR MLS ECS CYS
AND TO DEN WITH DWPTS IN THE MID TO UPPER 60S ACROSS CWFA. THTA-E RIDGE
AXIS EXTENDS NORTH ACROSS WRN NEB WITH WEAK Q VECTOR CONVERENGE
INDICATED IN NERN CO INTO THE NERN PANHANDLE THIS EVENING THEN AREA OF
CONVERGENCE INCREASES ACROSS WRN NEBRASKA AFT MIDNIGHT. 5H SHORTWAVE TO
THE WEST APPEARS TO BE WEAKENING AS IT MOVES EAST YET WITH DRIER AIR
AND COOLER TEMPERATURES ALOFT TO THE WEST WILL KEEP CHANCE FOR TSTMS IN
FCST BEYOND EVENING. MEAN RH INDICATES DRIER AIR AT 30% OR LESS MOVING
INTO THE PANHANDLE AND NWRN FA TONIGHT BUT MAY BE OVERDONE SINCE TROUGH
AXIS REMAINS TO THE WEST UNTIL SUNDAY MORNING. DWPT MACRO KEEPS
READINGS IN THE UPPER 50S TO MID 60S EXTREME WEST AND WILL BREAK OFF
PANHANDLE COUNTIES WITH LESS CHANCE FOR STRATUS DECK TO REDEVELOP AS
FAR WEST TONIGHT. TEMP GUIDANCE LOOKS TOO COOL CONSIDERING PRESENT
DWPTS AND STAY CLOSE TO GOING FORECAST.

SUNDAY NEXT 5H ELONGATED SHORTWAVE MOVES INTO THE WEST DURING THE
MORNING. 8H AND SFC TROUGH AXIS OVER WRN NEB WILL MOVE EAST DURING THE
DAY WITH LARGE AREA Q-VECTOR CONVERGENCE INDICATED ACROSS THE SOUTWHEST
THROUGH AFTERNOON THEN DIMINISHING. MAIN LIFT APPEARS TO PASS TO THE
NORTH WITH 5H WAVE WEAKENING AS UPPER RIDGE REBUILDS TO THE SOUTWHEST
WITH BROAD FLOW PATTERN IN THE W. BEST CHANCE FOR TSTMS TO BE DURING
THE AFTN AS SFC HEATING COMBINED WITH COOLING 5H TEMPERATURES INCREASE
LASPE RATES.

SUNDAY NIGHT SUBSIDENCE TO INCREASE IN THE WEST WITH CHANCE OF TSTMS
DECREASING AS FRONT MOVES EAST. NCNTRL MAY CONTINUE TO SEE FEW STORMS
IN THE EVENING OTHERWISE DECREASING CLOUDS. FAN GUIDANCE FOLLOWED.
SFC RIDGE AXIS EXTENDS EAST DURING DAY MONDAY WHILE A 5H WAVE MOVES
EAST DURING THE AFTERNOON. FOR PRESENT WILL LEAVE MONDAY DRY WITH BEST
CHANCE OF TSTMS TO OCCUR IN THE EVENING.

PRELIMINARY GUIDANCE FOR COORDINATION ONLY.  OFFICIAL FORECASTS ARE
CONTAINED WITHIN PRODUCT OMAZFPLBF.

CCF
LBF EB 068/086 060/089 063 19232
OGA EB 065/088 060/091 063 19231
IML EB 062/088 060/091 065 19231
ANW EB 063/085 062/088 063 19-32
ONL BB 064/086 062/088 065 19-32
BBW BB 065/086 062/088 065 19-22
VTN BB 065/089 060/092 063 1922-

WOOD