Area Forecast Discussion
Issued by NWS Cheyenne, WY

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FXUS65 KCYS 221139
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
439 AM MST THU JAN 22 2015

.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 423 AM MST THU JAN 22 2015

A VERY NICE STRETCH OF WEATHER SETTING UP ACROSS THE FORECAST
AREA. A GRADUAL WARMING TREND WILL START TODAY AND CONTINUE
RIGHT INTO THE WEEKEND. CLEAR SKIES AND WESTERLY DOWNSLOPE WINDS
WILL START THE WARMING PROCESS TODAY FOR AREAS EAST OF THE LARAMIE
RANGE. HIGH TEMPERATURES TODAY WILL BE 5 TO 10 DEGREES WARMER THAN
YESTERDAY.

A WEAK UPPER DISTURBANCE WILL PASS OVER THE AREA LATE TONIGHT AND
TOMORROW. THE MAIN IMPACT WILL BE INCREASED CLOUD COVER. A FEW
SNOW SHOWERS POSSIBLE IN THE MOUNTAINS BUT NOT EXPECTING MUCH IF
ANY SNOW ACCUMULATION. A FEW RAIN/SNOW SHOWERS ALSO POSSIBLE INTO
EAST CENTRAL WYOMING AND NEAR THE SOUTH DAKOTA/NEBRASKA BORDER BUT
ANY PRECIPITATION AMOUNTS WILL BE MINIMAL AT MOST. DRY WITH LESS
CLOUDS SATURDAY AND TEMPERATURES WARMING INTO THE 30S WEST TO NEAR
50 DEGREES INTO THE PLAINS.

.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 423 AM MST THU JAN 22 2015

WINDY CONDITIONS WILL BE LIKELY ON SUNDAY MORNING AND AFTERNOON
WITH THE GFS H85 CAG-CPR GRADIENT AROUND 60 METERS AND 750
MILLIBAR WINDS APPROACHING 50 KTS OVER BORDEAUX INTO THE SOUTH
LARAMIE RANGE. THOSE AREAS SHOULD BE MORE FAVORABLE FOR LOCALIZED
GUSTS EXCEEDING WARNING CRITERIA EARLY IN THE DAY WITH A MORE
WEST-EAST ORIENTATION OF LOWER LEVEL GRADIENTS. NOT LOOKING LIKE
WIDESPREAD HIGH WINDS. OTHERWISE A TRANQUIL WEATHER PATTERN IS
EXPECTED THROUGH THE PERIOD. BROAD SCALE UPPER RIDGING WILL BUILD
OVER THE CENTRAL ROCKIES BEHIND A VIGOROUS MID-LEVEL SHORTWAVE
DIVING INTO THE PLAINS. THE GFS/ECMWF BOTH SHOW H7 TEMPS IN EXCESS
OF 2-4 DEG C ON MON-TUE...WITH THE ECM SUGGESTING AS WARM AS 9 DEG
C AT 00Z WED EAST OF THE LARAMIE RANGE. ALL OF THE AVAILABLE MOS
GUIDANCE INDICATES POTENTIAL FOR HIGHS IN THE MID 50S ON MON AND
LOW 60S ON TUE. LIMITING FACTOR FOR 60S WOULD BE THE GFS SOLUTION
WITH A LACK OF DOWNSLOPE/SOUTHERLY SURFACE WINDS...WHEREAS THE
ECMWF HANGS ON TO WEAK WEST-TO-SOUTHWEST FLOW. BUT...GIVEN SUCH
WARM AIR ALOFT AND A LACK OF ANY INVERSIONS...WENT AHEAD AND
BUMPED HIGHS UP SEVERAL DEGREES ABOVE GUIDANCE. NO CONCERNS FOR
PRECIP OR WINDS WITH VIRTUALLY NOTHING GOING ON BENEATH THE RIDGE.
GFS BUFKIT SOUNDINGS SHOW A WHOLE 1 KT OF 700 MILLIBAR FLOW ON TUE
AFTN. WHILE THE GFS AND ECMWF DIFFER IN THE EVOLUTION OF A
SHORTWAVE MOVING ONTO THE WEST COAST ON TUE/WED...BOTH SUGGEST A
GRADUAL BREAKDOWN IN THE RIDGE. THIS COMBINED WITH INCREASING
700-300 MILLIBAR MOISTURE AND BETTER OROGRAPHICS SHOULD OPEN THE
DOOR FOR MOUNTAIN SNOW SHOWERS LATER IN THE WEEK.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 432 AM MST THU JAN 22 2015

VFR CONDITIONS WILL OCCUR TODAY WITH FEW-TO-SCT COVERAGE OF HIGH
CIRRUS MOVING OVERHEAD. WINDS WILL GENERALLY BE LIGHT TODAY WITH
THE EXCEPTION OF THE WYOMING TERMINALS...WHERE GUSTS TO 20-25 KTS
ARE POSSIBLE THIS AFTERNOON. INCREASING CLOUDS ARE EXPECTED AFTER
01Z FRI WITH BASES LOWERING. HOWEVER...BROKEN VFR CIGS AROUND 5K
FEET SHOULD PREVAIL THROUGH 12Z.

&&

.FIRE WEATHER...
ISSUED AT 423 AM MST THU JAN 22 2015

A LONG PERIOD OF DRY WEATHER IS SETTLING IN ACROSS THE AREA.
VIRTUALLY NO MEASURABLE PRECIPITATION IS EXPECTED OVER SOUTHEAST
WYOMING OR THE NEBRASKA PANHANDLE THROUGH AT LEAST THE MIDDLE
OF NEXT WEEK. A WARMING TREND IS ALSO SETTING UP WITH TEMPERATURES
MUCH ABOVE NORMAL GOING INTO NEXT WEEK.

&&

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

$$

SHORT TERM...SML
LONG TERM...CLH
AVIATION...CLH
FIRE WEATHER...SML



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