Area Forecast Discussion
Issued by NWS Cheyenne, WY

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000
FXUS65 KCYS 311821
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1221 PM MDT THU JUL 31 2014

.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 345 AM MDT THU JUL 31 2014

CURRENT SATELLITE PIX SHOW BACK END OF CLOUD CANOPY NEARING THE
WY/NE STATELINE AT 09Z. AT ITS CURRENT PACE IT WILL BE EAST OF THE
CWA BY SUNRISE...RESULTING IN A MOSTLY SUNNY START TO THE DAY FOR
MOST PLACES. THE EXCEPTION WILL BE ALONG THE I80 CORRIDOR WITH THE
POSSIBILITY OF PATCHY FOG AS DEW POINT DEPRESSIONS HOVER BETWEEN
1-3F AND WINDS ARE RELATIVELY LIGHT. ANY FOG THAT IS ABLE TO
DEVELOP THIS MORNING WILL BURN OFF BY MID-MORNING. OTHERWISE...
EXPECT A DRY DAY AHEAD AS THE BEST MONSOONAL MOISTURE PLUME HAS
BEEN SHUNTED TO THE SOUTH. THERE IS A SMALL CHANCE THAT THERE MAY
BE JUST ENOUGH MOISTURE FOR A FEW AFTERNOON SHOWERS/THUNDERSTORMS
OVER THE SNOWY/SIERRA MADRES...BUT CONFIDENCE IS NOT ALL THAT HIGH
AT THIS POINT. ANY CONVECTION THAT MIGHT DEVELOP WILL BE WEAK AND
PUSH SOUTHEAST INTO COLORADO SHORTLY AFTER DEVELOPMENT.

LIGHT NORTHWEST FLOW PREVAILS AGAIN FOR FRIDAY. AVAILABLE
MOISTURE WILL BE SLIGHTLY HIGHER FOR FRIDAY AS PROGD PWATS CLIMB A
FEW TENTHS OF AN INCH. TO VARYING DEGREES...00Z MODEL DATA TRACKS
WEAK SHORTWAVE ENERGY INTO THE AREA DURING THE AFTERNOON HOURS.
THE NAM EVEN DROPS A WEAK ATTENDANT SFC BOUNDARY INTO NRN AND WRN
ZONES. SO DID KEEP SMALL CHANCES FOR ISOLATED THUNDERSTORM
ACTIVITY MAINLY ALONG AND WEST OF THE LARAMIE RANGE AND ALONG THE
PINE RIDGE FOR FRIDAY. SBCAPES ARE STILL ONLY 200-500 J/KG WHICH
WILL HOLD CONVECTION STRENGTH DOWN.

RIDGE AXIS BUILDS NORTH TOWARDS THE CWFA FOR SATURDAY. PWATS ARE
PROGD TO BE SLIGHTLY LESS ON SATURDAY AND WITH WARMING MID-LEVEL
TEMPERATURES...NOT EXPECTING MUCH IN THE WAY CONVECTIVE COVERAGE
AGAIN. DID MAINTAIN SOME SMALL CHANCES GOING FOR AREAS ALONG AND
WEST OF THE LARAMIE RANGE...WHICH SHOULD BE IN CLOSER PROXIMITY TO
THE SUB-TROPICAL MOISTURE PLUME.

A WARMING TEMPERATURE TREND WILL PREVAIL THRU THE PERIOD AS THE
RIDGE AXIS AND ASSOCIATED LLVL THERMAL RIDGE AMPLIFIES. TODAY WILL
BE THE COOLEST DAY...WITH HIGHS REACHING THE 70S FOR LOCATIONS
ABOVE 4500 FEET AND 80S BELOW. THE 80 DEGREE ISOTHERM CLIMBS TO
AROUND 5000 FEET FOR FRIDAY AND 5500 FEET FOR SATURDAY.

.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 345 AM MDT THU JUL 31 2014

DRY AND WARM CONDITIONS ACROSS THE CWA SUNDAY AS MONSOONAL
MOISTURE WILL CONTINUE TO ROTATE TO THE WEST OF THE CWA. MOISTURE
WILL THEN SPREAD ACROSS THE AREA ON MONDAY AS A WEAK UPPER
LOW/TROF LIFTS OUT OF THE DESERT SW AND PHASES WITH A WEAK UPPER
TROF OVER THE PACIFIC NW. THIS FEATURE WILL MOVE ACROSS THE CWA
TUESDAY INTO WEDS BRINGING AT LEAST SCTD SHOWERS AND A FEW TSTMS
TO MUCH OF THE CWA. DRIER WEATHER TO RETURN THURSDAY BEHIND THIS
SYSTEM WITH TEMPS REMAINING CLOSE TO SEASONAL AVERAGES.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY MORNING)
ISSUED AT 1220 PM MDT THU JUL 31 2014

VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD UNDER RELATIVELY DRY
NORTHWEST FLOW ALOFT. AN ISOLATED SHOWER OR TWO REMAINS A
POSSIBILITY OVER THE MOUNTAINS THIS AFTERNOON. WINDS WILL REMAIN
LIGHT...EXCEPT FOR PORTIONS OF CARBON COUNTY WHERE GUSTS TO 20 KTS
ARE POSSIBLE THIS AFTERNOON.

&&

.FIRE WEATHER...
ISSUED AT 345 AM MDT THU JUL 31 2014

NO FIRE WEATHER CONCERNS SEEN AT LEAST THROUGH THE MIDDLE OF NEXT
WEEK AS WINDS REMAIN LIGHT AND TEMPERATURES NEAR SEASONAL LEVELS.
THERE WILL BE SOME SMALL CHANCES FOR AFTERNOON AND EVENING SHOWER/
THUNDERSTORM ACTIVITY ESPECIALLY IN PORTIONS OF THE DISTRICT ALONG
AND WEST OF THE LARAMIE RANGE. TEMPERATURES WILL GRADUALLY WARM
THROUGH THE WEEKEND WITH THE 80 DEGREE TEMPERATURE LINE REACHING
AROUND 6000 FEET FOR THE WEEKEND. MINIMUM HUMIDITIES SHOULD FALL
INTO THE 20 TO 30 PERCENT RANGE THROUGH THE WEEKEND FURTHER
MITIGATING CRITICAL FIRE WEATHER CONDITIONS. THE NEXT CHANCE FOR
MORE SUBSTANTIAL PRECIPITATION RETURNS TO THE AREA EARLY NEXT
WEEK.

&&

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

$$

SHORT TERM...HAHN
LONG TERM...RE
AVIATION...RJM
FIRE WEATHER...HAHN






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