Flash Flood Warning 1, NWS Riverton, WY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
200 PM MDT WED MAY 17 2000

CRNT WX...CRNT FCST ON TRACK WITH SOAKING RAINS DEVELOPING LATE THIS
MNG MOST AREAS EAST OF CONT DVD.  SFC AND UPR LOWS CURRENTLY LCTD IN
NERN/ERN COLORADO RSPTVLY.  RAIN RESULT OF COMBO OF DEEP UPSLP/UPR
DYNAMICS.  EARLIER UPDATED TO ADD EMBEDDED THUNDER... MAINLY EAST
WHERE COOLEST TEMPS ALOFT AND STRONGEST DYNAMICS.  WEST OF DVD...RKS
HAS RPTD RA WITH OCNL CHNGOVR TO SN.  MEANWHILE KBPI RPTG ASOS CLR
WITH NW DOWNSLOPE...AND MANY OTHER WRN SITES DRY.

OF THE 3 MAIN MDLS ETA HAS BEEN MOST CONSISTENT LAST FEW RUNS WITH
QPF WITH THE LATEST GIVING 1 TO 1.5 INCHES OVER WIND RVR BSN AND ERN
CWA FOR 24 HOURS ENDING 18/12Z.  MAY BE A LITTLE OVERDONE FOR FORMER
BUT MORE ON TRACK FOR ERN AREAS WHERE UPSLOPE AND DYNAMICS STRONGER.
MDLS PRETTY MUCH IN AGREEMENT IN PLACEMENT AND TIMING OF EASTWARD
MOVG LO WITH PCPN ENDING DURING OVNT PD. FZG LVLS PROGGED TO DROP
FROM 10K FT TO AROUND 8K FT BEFORE PCPN END.  WILL CONTINUE MENTION
OF SNOW IN HIGHER ELEV.

CONDITIONS TO IMPROVE LATE TONIGHT/TOMORROW WITH EXITING SYSTEM AND
APRCH OF WEAK SFC/UPR RIDGE FROM NW. AVN/MRF ADVERTISING MAINLY DRY
CONDITIONS WITH WARMUP INTO WKEND WITH MAIN STORM TRACK STAYING
NORTH.

.RIW...NONE.

DZ

WYZ005-009-026>028-172120-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE RIVERTON WY
220 PM MDT WED MAY 17 2000

...HEAVY SNOW WAS FALLING OVER THE BIG HORN MOUNTAINS...

REPORTS FROM BUFFALO AND THE WYOMING HIGHWAY DEPARTMENT SHOWED HEAVY
SNOW WAS FALLING OVER THE BIG HORNS. SNOWFALL WAS REPORTED OVER THE
SOUTH REACHES OF THE BIG HORNS NEAR ARMINTO WITH SNOW FALLING NORTH
THROUGH THE BIG HORNS AS FAR NORTH AS BUFFALO. POWDER RIVER PASS ON
U.S. HIGHWAY 16 WAS CLOSED AS OF 135 PM.

PERSONS WISHING TO TRAVEL THROUGH THIS AREA THIS AFTERNOON AND EVENING
SHOULD TAKE ANOTHER ROUTE OVER LOWER ELEVATIONS WHERE MOST OF THE
PRECIPITATION WILL BE RAIN. SNOW WILL CONTINUE OVER THE HIGHER
ELEVATIONS OF THE BIG HORN MOUNTAINS THROUGH THIS EVENING BEFORE ENDING
LATE TONIGHT.

WCJIN-WYNE-WYNW-
CLARK

WYZ012>015-180130-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE RIVERTON WY
536 PM MDT WED MAY 17 2000

...SNOW FALLING IN PARTS OF CENTRAL WYOMING...

AT 530 PM MDT...SNOW WAS FALLING IN PARTS OF CENTRAL WYOMING FROM
SOUTHERN NATRONA COUNTY TO SOUTHERN FREMONT COUNTY.  STORM SPOTTERS
FROM BEAVER RIM TO JEFFERY CITY AND FROM JEFFERY CITY TO MUDDY GAP
REPORTED 2 TO 3 INCHES OF SNOW ON THE GROUND WITH A WET SNOW STILL
FALLING.  FARTHER EAST IN NATRONA COUNTY RAIN WAS REPORTED AT THE
MARINA AT ALCOVA.

THE ROADS WERE REPORTED TO BE SLUSHY WITH MOST OF THE SNOW STICKING IN
THE FIELDS.  MUCH OF THE SNOW IS EXPECTED TO MELT AS IT FALLS WITH WARM
GROUND.  LOCAL SNOW ACCUMULATIONS OF 5 TO 6 INCHES CAN BE EXPECTED
IN SOME OF THE HIGHER ELEVATIONS OF THE MOUNTAINS IN SOUTHERN FREMONT
AND SOUTHERN NATRONA COUNTIES.

THE PRECIPITATION IS EXPECTED TO TAPER OFF AROUND MIDNIGHT WHEN SOME
AREAS OF FOG WILL FORM.

WCJIN-WYNW-WYNE

C. BAKER