Severe Thunderstorm Warning 59, NWS Cheyenne, WY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
152 PM MDT WED JUL 12 2000

PATTERN OVR THE ROCKIES WILL REMAIN SIM THRU FRI WITH THE LRG RDG
ALFT OVR THE AREA CONTG.  MDLS DIFFER ON LCTN OF AXIS AND AMPLITUDE
OF RDG AND BASED ON BTR RUN TO RUN CONTINUITY WILL FOLLOW THE ETA MORE
CLOSELY.  THE ETA CONTS TO DRIFT THE UPR HI CENTER SLWLY W AND HAS
LESS AMPLITUDE WITH THE RDG AXIS THAN THE AVN OR NGM.  WITH THE HI
HGTS AND WARM TEMPS ALFT ASOCTD WITH THE RDG...ABV NORMAL TEMPS WILL
PERSIST FOR THIS FCST OVR THE CWA.  QUITE A BIT OF MID AND UPR LVL
MSTR IS TRAPPED ARND THE HI AND SO QSTN IS CVRG AND TIMING OF
TSTMS.  SHRTWV TROF FROM CNTRL UT TO S CNTRL CO ERY THIS AFTN WILL
MOV ARND THE RDG AND FINALLY EXIT THE ERN PRTN OF THE CWA JUST BFR
12Z.  WITH THE WARM TEMPS ALFT...ETA DEPICTS WELL THE FTR AT H250.
TSTM CVRG WILL BE GREATEST IN THE SRN PRTN OF THE CWA...E OF THE
LARAMIE RANGE IN THE BTR MSTR.  SVR TSTMS STILL PSBL TIL 06Z OVR THE
SE CRNR OF WY AND THE SRN NEB PNHNDL WITH MAIN NEG FACTOR BEING THE
WARM TEMPS ALFT.  LO LIS AND HI CAPES ALG WITH GOOD DIRECTIONAL
SHEAR SHUD PROVIDE FOR HVY RAIN...SOME LRG HAIL AND STG WIND
GSTS...ESP IN XTRM SE WY AND THE SRN NEB PNHNDL 00Z TO 06Z.  MDLS
HAV HIR HGTS AND A LACK OF SHRTWV TROFS FOR THU AFTN AND NGT AND
MEAN RH IS LESS THAN THAT OF THIS AFTN...SO WILL LEAVE OUT POPS FORM
THU AND WITH THE NOCTURNAL TREND DUE TO THE WARM TEMPS ALFT WILL HAV
LO POPS FOR THU NGT.  SHRTWV TROF APRCHS FOR FRI AFTN AND WILL AGN
HAV LO POPS AT THAT TIME.

.EXTENDED DISCUSSION...
PATTERN WITH UPR LVL RDG THRU THE PLAINS AND ROCKIES WILL CONT FOR
THE NEXT SEVERAL DAYS. THE RDG BECOMES SOMEWHAT FLATTENED OVER THE
WEEKEND INTO EARLY NEXT WITH THE CANADIAN SYSTEM PASSING TO THE
NORTH. DIFFICULT TO TIME CONVECTION AS IT WILL BE LARGELY DEPENDENT
ON SHORT WAVES MOVING AROUND THE RDG. NEXT SIG SHORT WAVE PROGGED
BY MRF INTO SRN WY SAT NIGHT/SUN MORN. OTHERWISE...CONTINUED VERY
WARM TEMPS.

.CYS...
WY...NONE.
NE...NONE.

WEILAND/STARK

WYZ059>070-NEZ001>003-019>021-054-055-121900-

SEVERE WEATHER OUTLOOK...CORRECTED
NATIONAL WEATHER SERVICE CHEYENNE WY
1108 AM MDT WED JUL 12 2000

SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON AND EVENING.

DISCUSSION...THE AIR MASS OVER SOUTHEAST WYOMING AND THE WESTERN
NEBRASKA WILL BE MOIST AND UNSTABLE THIS AFTERNOON AND EVENING...
ESPECIALLY EAST OF THE LARAMIE RANGE.  IN ADDITION...AN UPPER AIR
DISTURBANCE WILL MOVE OVER THE AREA LATE THIS AFTERNOON AND TONIGHT.
THUNDERSTORMS WILL DEVELOP IN THE AREA ALONG AND WEST OF THE LARAMIE
RANGE BY 3 PM AND THEN SPREAD EAST THROUGH THE EVENING.  WITH THE WARM
TEMPERATURES ALOFT...MOST OF THE STORMS THROUGH THE AFTERNOON WILL
PRODUCE WIND GUSTS TO 45 MPH AND MODERATE RAINFALL.  HOWEVER DURING
THE EVENING TO THE EAST OF THE LARAMIE RANGE AND MAINLY SOUTH OF A
WHEATLAND TO ALLIANCE LINE THE STORMS WILL HAVE THE POTENTIAL TO
PRODUCE LARGE HAIL...HEAVY RAIN AND STRbONG WIND GUSTS.  ALL OF THE
THUNDERSTORMS WILL MOVE TO THE NORTHEAST AT 20 MPH...WITH THE STRONG
STORMS MOVING MORE TO THE EAST OR SOUTHEAST.

 $$

WEILAND

WCJIN-WYSE-WYNE

WYZ068-070-NEZ001>003-019>021-054-055-130300-

SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHEYENNE WY
239 PM MDT WED JUL 12 2000

...A SEVERE THUNDERSTORM WATCH POSTED UNTIL 9 PM...

A SEVERE THUNDERSTORM WATCH WAS POSTED FOR GOSHEN AND EASTERN
LARAMIE COUNTIES AND THE NEBRASKA PANHANDLE UNTIL 9 PM. THIS WATCH
INCLUDES THE WYOMING CITIES OF PINE BLUFFS AND TORRINGTON. THIS
WATCH DOES NOT INCLUDE CHEYENNE. IN THE NEBRASKA PANHANDLE IT
INCLUDES COUNTIES OF BOX BUTTE...CHEYENNE...BANNER...DAWES...
KIMBALL...MORRILL...SCOTTS BLUFF...AND SIOUX. THE FOLLOWING NEBRASKA
CITIES ARE INCLUDED IN THIS WATCH SIDNEY...CHADRON...
ALLIANCE...KIMBALL...AND SCOTTSBLUFF.
 e

DEAL

WCJIN-WYSE