Severe Thunderstorm Warning 27, NWS Cheyenne, WY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
921 AM MDT SAT JUN 10 2006

.UPDATE...ONE SHORTWAVE TROUGH IS PUSHING THROUGH SE WY THIS
MORNING WITH ANOTHER OVER SW WY. HAVE ADDED SOME MORNING TSTMS TO
SOUTHERN NEBRASKA PANHANDLE AND TO CARBON...ALBANY AND CONVERSE
COUNTIES IN WY TO COVER THINGS.                         JLH

&&

.PREV DISCUSSION... (ISSUED 329 AM MDT SAT JUN 10 2006)

SHORT TERM...THROUGH TONIGHT. MOIST SOUTHWESTERLY FLOW ALOFT WILL
CONTINUE OVER THE AREA TODAY BEFORE VEERING TO MORE OF A WESTERLY
COMPONENT TONIGHT. A WEAK SURFACE COLD FRONT HAS NUDGED
SOUTHWESTWARD EARLY THIS MORNING AND IS THROUGH THE PLAINS OF
SOUTHEAST WY. IT WILL LOSE MOST OF ITS PUSH TODAY AND WILL BECOME
QUASISTATIONARY AS IT STALLS IN THE VICINITY OF THE LARAMIE RANGE.
THE SURFACE BOUNDARY WILL SERVE AS A FOCUS FOR CONVECTION AS LOW
LEVEL UPSLOPE FLOW NORTH AND EAST OF THE FRONT CONVERGES WITH
SOUTHWESTERLY FLOW SOUTH AND WEST OF THE FRONT. FORECAST CONVECTIVE
PARAMETERS APPEAR TO SUPPORT SOME SEVERE WEATHER THIS AFTERNOON
UNTIL MID EVENING AS PROGGED SOUNDINGS INDICATE GOOD SPEED AND
DIRECTIONAL WIND SHEAR AS WELL AS GOOD INSTABILITY. THE PRIMARY
THREAT LATER TODAY APPEARS TO BE THE POSSIBILITY OF SEVERE HAIL.
TEMPERATURES TODAY WILL BE CLOSER TO NORMAL...REACHING THE MID 70S
TO LOWER 80S IN MOST AREAS OUTSIDE THE MOUNTAINS. SEVERE STORMS WILL
REMAIN POSSIBLE UNTIL 03Z OR SO BEFORE LOSING INTENSITY AND AERIAL
COVERAGE AS DRIER AIR WORKS IN FROM THE WEST. WILL LINGER CONVECTION
UNTIL AROUND MIDNIGHT OR SO THEN GO DRY LATE TONIGHT.

LONG TERM...HEIGHTS ALOFT START TO RISE OVER THE CWA ON SUNDAY WITH
THE RIDGE AXIS OVER THE HIGH PLAINS THROUGH WEDNESDAY ON ALL
MODELS.  THE BOUNDARY LAYER UPSLOPE WIND FLOW WILL PERSIST THROUGH
MONDAY...BEFORE A SURFACE LOW PRESSURE TROUGH MOVES EAST OF MUSCH OF
THE CWA TUESDAY AND WEDNESDAY.  SUNDAY AND MONDAY WILL SEE MORE
AFTERNOON AND EVENING THUNDERSTORMS AND LATE NIGHT AND EARLY MORNING
SHOWERS OVER ESPECIALLY THE EAST PART OF THE CWA.  MOST PARAMETERS
STILL INDICATE THE GOOD POSSIBILITY OF SEVERE STORMS IN THE EAST
PART OF THE CWA.  DRIER AIR MOVES OVER THE REGION FOR TUESDAY AND
CONTINUES FOR WEDNESDAY AND WILL EITHER LOWER OR TAKE OUT POPS FOR
THOSE DAYS.  AFTER A STILL RELATIVELY COOL DAY ON SUNDAY...THE
TEMPERATURES WILL THEN WARM EACH DAY THROUGH WEDNESDAY.  DRIER AND
WARMER AIR AND BREEZY CONDITIONS ON TUESDAY AND WEDNESDAY OVER SOUTH
CENTRAL WYOMING MAY CREATE A CRITICAL FIRE WEATHER SITUATION.  LOW
CLOUDS WILL CONTINUE TO BE A POSSIBILITY OVER THE EAST PART OF THE
CWA IN THE LATE NIGHT AND EARLY MORNING HOURS IN THE MOIST BOUNDARY
LAYER UPSLOPE WIND FLOW.  REMAINDER OF THE FORECAST IS HANDLED
DIFFERENTLY BY THE MODELS WITH THE MODELS NOW MORE PROGRESSIVE WITH
THE LARGE AMPLITUDE UPPER LEVEL TROUGH LATER IN THE WEEK.  THE 18Z
DGEX IS THE FASTER IN MOVING THE FILLING FEATURE EAST WITH THE
TROUGH PASSAGE OVER THE CWA AROUND 12Z THURSDAY.  THE GFS
MEANWHILE...ALSO TRENDING FASTER...HAS THE TROUGH PASSAGE AROUND 06Z
FRIDAY.  THE ASSOCIATED SURFACE COLD FRONT MOVES THROUGH AT SIMILAR
TIMES.  MODELS THEN HAVE A MORE ZONAL FLOW OVER THE WESTERN U.S. FOR
NEXT WEEEKND.  WILL COMPROMISE THE TIMING BETWEEN THE GFS AND DGEX
AND MOVE THE COOLER AIR OVER THE CWA THURSDAY EVENING.  THE HIGHEST
POPS WILL PROBABLY BE AHEAD OF SHORTWAVE TROUGH THURSDAY AFTERNOON
AND EVENING AND THEN LOWER THROUGH THE WEEKEND AS THE ATMOSPHERE
DRIES.  THE TEMPERATURES WILL ALSO TURN COOLER ON FRIDAY AND
SATURDAY.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.

&&

SHORT TERM...ROBINSON
LONG TERM....WEILAND

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHEYENNE WY
1000 MDT SAT JUN 10 2006

NEZ001>003-019>021-054-055-WYZ059-060-067>070-111100-
SIOUX-DAWES-BOX BUTTE-SCOTTS BLUFF-BANNER-MORRILL-KIMBALL-
CHEYENNE-CONVERSE-NIOBRARA-PLATTE-GOSHEN-CHEYENNE FOOTHILLS-
PINE BLUFFS-
1000 MDT SAT JUN 10 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE WESTERN NEBRASKA
PANHANDLE AND SOUTHEAST WYOMING.

.DAY ONE...TODAY AND TONIGHT

SCATTERED THUNDERSTORMS WILL DEVELOP ACROSS THE AREA EARLY THIS
AFTERNOON AS A DISTURBANCE MOVES ACROSS SOUTHEAST WYOMING AND THE
NEBRASKA PANHANDLE.  A VERY MOIST AND UNSTABLE ATMOSPHERE WILL
RESULT IN SOME SEVERE STORMS ACROSS THE AREA...EAST OF THE LARAMIE
RANGE.  THE MAIN THREAT WITH THE STORMS WILL BE LARGE HAIL AND HEAVY
RAIN.  THE STORMS WILL MOVE EAST OF THE NEBRASKA PANHANDLE EARLY
THIS EVENING.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THUNDERSTORMS WILL BE OVER MUCH OF SOUTHEAST WYOMING AND THE
WESTERN NEBRASKA PANHANDLE SUNDAY AND MONDAY AFTERNOON.  THE
STORMS WILL BE LESS NUMEROUS TUESDAY THROUGH FRIDAY...
ESPECIALLY ON TUESDAY AND WEDNESDAY. SOME OF THE STORMS
SUNDAY AFTERNOON AND EVENING WILL PRODUCE SEVERE WEATHER.

THE SEVERE DROUGHT CONTINUES OVER THE SOUTHERN NEBRASKA
PANHANDLE.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL LIKELY BE NEEDED THIS AFTERNOON INTO THE
EARLY EVENING.

WYZ061>066-111100-
SOUTHWEST CARBON-NORTH CARBON-SNOWY RANGE-NORTH LARAMIE RANGE-
LARAMIE VALLEY-LARAMIE RANGE-
1000 MDT SAT JUN 10 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST WYOMING.

.DAY ONE...TODAY AND TONIGHT

A SCATTERED COVERAGE OF THUNDERSTORMS WILL CONTINUE TO MOVE ACROSS
THE AREA THROUGH THIS AFTERNOON.  THE THUNDERSTORMS ARE NOT EXPECTED
TO BECOME SEVERE...BUT BRIEF AND LOCAL WIND GUSTS TO 40 MPH
AND LIGHTNING ARE POSSIBLE.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

ISOLATED THUNDERSTORMS WILL DEVELOP SUNDAY AND MONDAY AFTERNOON
AND EVENING...WITH GENERALLY DRY CONDITIONS BY TUESDAY.
WARM AND DRY CONDITIONS AND INCREASING SOUTHWEST WINDS MAY
CREATE CRITICAL FIRE WEATHER CONDITIONS TUESDAY THROUGH
THURSDAY OVER THE LOWER ELEVATIONS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED.

WEILAND