Area Forecast Discussion Issued by NWS Cheyenne, WY
000
FXUS65 KCYS 150003
AFDCYS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
603 PM MDT FRI JUN 14 2013
.UPDATE...
ISSUED AT 602 PM MDT FRI JUN 14 2013
SHOWERS AND THUNDERSTORMS HAVE DEVELOPED ALONG A BOUNDARY WHICH
MOVED NORTH AND INTO CENTRAL LARAMIE COUNTY LATE THIS AFTERNOON.
THE STRONGEST STORM AS OF 2345Z WAS JUST NORTH OF KCYS WITH
SMALL HAIL...FREQUENT LIGHTNING AND HEAVY RAIN ASSOCIATED.
SIGNIFICANT ISENTROPIC LIFT WILL TAKE PLACE TONIGHT ALONG WITH
AN INCREASE IN MOISTURE. CLOUDS SHOULD DEVELOP EARLY TONIGHT
WITH BASES LOWERING LATER TONIGHT. SOME SHOWERS AND STORMS CAN
BE EXPECTED AS THE NIGHT GOES ON ALONG WITH AREAS OF FOG NEAR
AND WEST OF KCYS. IN A RECENT UPDATE ADJUSTED POPS AND BUMPED
LOW TEMPERATURES UP A BIT FOR TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 234 PM MDT FRI JUN 14 2013
UPPER LEVEL CLOUDS HAVE SHIFTED EAST THIS AFTERNOON ALLOWING
TEMPERATURES TO REACH THERE EXPECTED TEMPERATURES BUT NOW STARTING
TO SEE SOME CUMULUS POP TOWARD CHEYENNE. CAN NOT COMPLETELY RULE
OUT A SHOWER OR THUNDERSTORM FROM DEVELOPING LATE THIS AFTERNOON
BUT SHOULD STAY CAPPED. SLIGHT CHANCE FOR SHOWERS AND
THUNDERSTORMS STARTING THIS EVENING AND INTO THE OVERNIGHT AS
MIDLEVEL THETAE ADVECTION INCREASES. MODELS DO SHOW SOME ELEVATED
CAPE AND AVAILABLE EFFECTIVE SHEAR BUT CHANCES FOR SEVERE
THUNDERSTORMS IS LOW AS BEST. LOW LEVEL MOISTURE WILL CONTINUE TO
INCREASE TONIGHT SO COULD SEE LOW STRATUS AND FOG TOWARD CHEYENNE
AND INTO THE SOUTHERN LARAMIE RANGE. COULD EVEN SEE SOME SOME
DENSE FOG NEAR THE SUMMIT TOWARD SUNRISE.
CHANCES FOR THUNDERSTORMS WILL CONTINUE SATURDAY AND
SUNDAY...WITH THE MAIN THREAT INTO THE NEBRASKA PANHANDLE LATE
AFTERNOON AND EVENING...ALTHOUGH STORMS MAY BE POSSIBLE FARTHER
WEST. INCREASING LOW LEVEL MOISTURE AND INSTABILITY ALONG WITH
DEEP LAYER SHEAR WILL LIKELY SET THE STAGE FOR SEVERE
THUNDERSTORMS. LOW CLOUDS MAY LINGER THROUGH THE MORNING
SATURDAY...WHICH COULD INHIBIT DEEPER MIXING WITH A CAP INHIBITING
CONVECTION...SIMILAR TO WHAT OCCURRED YESTERDAY. SUNDAY AFTERNOON
MAY ACTUALLY BE THE HIGHER CHANCE FOR THUNDERSTORMS ESPECIALLY IF
A WEAK SHORTWAVE CAN SLIP ACROSS THE AREA.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 234 PM MDT FRI JUN 14 2013
NO SIGNIFICANT CHANGES SEEN INTO THE MID PART OF NEXT WEEK AS AN
UPPER RIDGE AMPLIFIES OVER THE ROCKIES THEN SHIFTS EAST SLOWLY
THROUGH WEDNESDAY. IMPULSES WILL PASS ACROSS THE REGION AND HELP TO
PRODUCE WIDELY SCATTERED MAINLY AFTERNOON AND EVENING SHOWERS AND
STORMS THROUGH WEDNESDAY. AN UPPER LOW OVER THE PACIFIC NW WILL
EJECT SLOWLY EASTWARD LATE IN THE WEEK AND SHOULD PUSH A COOL FRONT
ACROSS THE CWA WEDS NIGHT. DRIER WESTERLY FLOW BEHIND THE FRONT
SHOULD REDUCE CONVECTION FOR THURSDAY AND FRIDAY. NO REAL COOLING
EFFECT FROM THE FRONT THOUGH WITH TEMPERATURES STAYING CLOSE TO
SEASONAL LEVELS THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY AFTERNOON)
ISSUED AT 536 PM MDT FRI JUN 14 2013
CLOUDS WILL INCREASE OVER THE CWA EARLY TONIGHT WITH BASES
LOWERING AFTER 05Z. MOST AREAS WILL HAVE CLOUD BASES LOWER TO
BETWEEN 3 AND 6 THOUSAND FEET AGL AFTET THAT TIME. BASES WILL
SSLOWLY RISE DURING THE DAY SATURDAY. THE EXCEPTION WILL BE THE
SOUTHEAST CORNER OF WYOMING. IFR CEILINGS AND MVFR OR IFR
VISIBILITIES IN FOG CAN BE EXPECTED 10Z AND 16Z. THAT AREA
INCLUDES KCYS AND THE SOUTHERN LARAMIE RANGE. SOME SHOWERS AND
THUNDERSTORMS WILL AFFECT AREAS EAST OF THE LARAMIE RANGE TONIGHT.
&&
.FIRE WEATHER...
ISSUED AT 234 PM MDT FRI JUN 14 2013
CHANCES FOR SHOWERS AND THUNDERSTORMS WILL MAINLY BE CONFINED TO
AREAS ALONG AND EAST OF THE LARAMIE RANGE THE NEXT SEVERAL DAYS WITH
DRY CONDITIONS TO THE WEST. SOME STRONG TO SEVERE THUNDERSTORMS WITH
BRIEF HEAVY RAIN IS POSSIBLE WITH THE THUNDERSTORMS IN THE EAST
WHILE AREAS WEST WILL CONTINUE TO DRY OUT. MAIN THUNDERSTORM CHANCE
WILL BE AFTERNOON AND EVENING ALTHOUGH A FEW SHOWERS AND
THUNDERSTORMS MAY LINGER INTO THE OVERNIGHT HOURS. THE FIRST CHANCE
FOR SHOWERS AND THUNDERSTORMS WILL BE THIS EVENING INTO THE
OVERNIGHT.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...WEILAND
SHORT TERM...LIEBL
LONG TERM...RE
AVIATION...WEILAND
FIRE WEATHER...LIEBL