Area Forecast Discussion
Issued by NWS Cheyenne, WY

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS65 KCYS 080244
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
844 PM MDT MON JUL 7 2014

.UPDATE...
ISSUED AT 820 PM MDT MON JUL 7 2014

A FEW PIECES OF ENERGY ASSOCIATED WITH A STRONG SHORTWAVE TROUGH
OVER THE NORTHERN PLAINS COMBINED WITH WEAK LLVL UPSLOPE FLOW TO
GENERATE A FEW TSTMS ALONG AND EAST OF THE LARAMIE RANGE EARLIER
THIS EVENING. MODERATELY STRONG MIDLVL FLOW WAS CONTRIBUTING TO
EFFECTIVE BULK SHEAR VALUES IN EXCESS OF 40 KTS. GOOD INSTABILITY
WITH CAPES AROUND 2000 J/KG PROVED SUFFICIENT FOR A FEW SEVERE
STORMS. MOST NOTABLY...GOLF BALL SIZED HAIL WAS REPORTED IN AND
AROUND SCOTTSBLUFF AROUND 23Z.

THE COLD FRONT THAT MOVED SOUTHWEST ACROSS THE CWA EARLIER HAS
NOW MOVED INTO NORTHERN CO. REGIONAL RADAR MOSAIC SHOWS THE BULK
OF CONVECTIVE ACTIVITY NOW BEING FOCUSED WITHIN LLVL CONVERGENCE
ALONG THAT BOUNDARY WITH CONTINUED CLEARING IN OUR CWA. REMOVED
POPS FOR THE REST OF THE NIGHT WITH A STABILIZING BOUNDARY LAYER
AND INCREASING SUBSIDENCE ALOFT. ALSO ADJUSTED CLOUD TRENDS. THE
REMAINDER OF THE FCST LOOKS GREAT WITH NO CHANGES REQUIRED.

&&

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 200 PM MDT MON JUL 7 2014

FORECAST CHALLENGES FOR THE SHORT TERM DEAL WITH SEVERE
THUNDERSTORM CHANCES THIS AFTERNOON.

CURRENTLY...WEAK COLD FRONT MOVED THROUGH SOUTHEAST WYOMING AND
NEBRASKA PANHANDLE THIS MORNING. WAS VERY DRY HERE IN SOUTHEAST
WYOMING AHEAD OF THE FRONT. EVEN NOW...HUMIDITY AT CHEYENNE IS
ONLY 15 PERCENT. DEWPOINTS OUT IN THE PANHANDLE HOWEVER...ARE IN
THE UPPER 50S WITH 60 BEING REPORTED AT SIDNEY. STORM PREDICTION
CENTER HAS MOVED THE SLIGHT RISK AREA FOR TODAY FURTHER NORTH AND
WEST TO ENCOMPASS OUT EASTERN ROW OF COUNTIES IN THE PANHANDLE.
LATEST RADAR MOSAIC SHOWING SOME PRETTY GOOD CONVECTION ONGOING UP
IN RAPID CITYS CWFA...BUT THESE ARE MOVING SOUTHEAST AND AWAY FROM
THE NORTHERN PANHANDLE. WILL HAVE TO WATCH FUTURE OUTFLOW
BOUNDARIES OFF THIS CONVECTION THAT COULD IMPACT OUR AREA.

LATEST WATER VAPOR IMAGERY SHOWING A MONSOON SURGE INTO NEVADA
THIS AFTERNOON. WITH THIS FRONT COMING DOWN FROM THE
NORTHWEST...IT HAS THWARTED ANY NORTHEAST SURGE...BUT THERE IS
CONVECTION BEGINNING TO BLOSSOM OVER CENTRAL AND WESTERN
COLORADO.

SMALL CAPPING INVERSION ANALYZED AT 650MB ON THE NAM SOUNDINGS FOR
THIS AFTERNOON OUT IN THE PANHANDLE THAT MAY BE JUST ENOUGH TO
HOLD OFF WIDESPREAD CONVECTION. SHOULD WE BE ABLE TO BREAK THAT
CAP THOUGH...THERE WILL BE ABOUT 2000-2500J/KG. KEPT SOME SMALL
CHANCE POPS IN FOR THE PANHANDLE THROUGH SUNSET TODAY. CONVECTION
SHOULD END PRETTY QUICK THEREAFTER.

BETTER CHANCES FOR CONVECTION TUESDAY AS WE HAVE MORE TIME FOR LOW
LEVEL MOISTURE TO POOL. RIDGE BREAKS DOWN A LITTLE MORE WITH SOME
PIECES OF ENERGY WORKING THROUGH THE RIDGE. STILL...MAJORITY OF
THE MOISTURE WILL BE SOUTH IN COLORADO.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 200 PM MDT MON JUL 7 2014

RIDGE CONTINUES TO BREAK DOWN THROUGH THE WEEK WITH INCREASING LOW
LEVEL MOISTURE. SHOULD HAVE DAILY CHANCES FOR AFTERNOON AND
EVENING CONVECTION AT LEAST THROUGH SATURDAY BEFORE WESTERLY
WINDS RETURN.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY AFTERNOON)
ISSUED AT 820 PM MDT MON JUL 7 2014

VFR CONDITIONS THROUGH THE REST OF THE NIGHT. SHOWERS AND TSTMS
HAVE ENDED ACROSS THE AREA THIS EVENING AS THE COLD FRONT MOVES
SOUTH INTO NORTHERN COLORADO. GUSTY AND ERRATIC WINDS ARE STILL
POSSIBLE WITH LINGERING OUTFLOW FROM EARLIER STORMS. NO NOTABLE
AVIATION CONCERNS FOR TUE.

&&

.FIRE WEATHER...
ISSUED AT 115 PM MDT MON JUL 7 2014

WEAK COLD FRONT MOVING INTO THE AREA FROM THE NORTH TODAY WILL
SHIFT WINDS NORTH AND NORTHEAST. WINDS BECOMING EASTERLY FOR AREAS
EAST OF THE LARAMIE RANGE. FRONT WILL STICK WITH US AND WILL
INTERACT WITH INCREASING MONSOONAL MOISTURE. DAILY CHANCES FOR
AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS THE REMAINDER OF
THE WEEK.

&&

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

$$

UPDATE...HAMMER
SHORT TERM...CLAYCOMB
LONG TERM...CLAYCOMB
AVIATION...GARMON/HAMMER
FIRE WEATHER...CLAYCOMB






USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.