Area Forecast Discussion
Issued by NWS Cheyenne, WY

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FXUS65 KCYS 261851
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1151 AM MST WED NOV 26 2014

.UPDATE...
ISSUED AT 1151 AM MST WED NOV 26 2014

WENT AHEAD AND CANCELLED THE WINTER STORM WARNINGS AND ADVISORIES
AS LITTLE TO NO ADDITIONAL SNOW IS EXPECTED TODAY FOR THESE AREAS.
BLOWING SNOW CONCERNS LOOK TO BE MINIMAL AS WELL BASED OFF A LOOK
AT WEBCAMS FROM ACROSS THESE AREA.

EXPANDED POPS AND INCREASED SNOW AMOUNTS OVER THE NEBRASKA
PANHANDLE AS RADAR AND SHORT TERM MODEL TRENDS SUGGEST THERE WILL
BE LIGHT SNOW OFF AND ON THRU THE AFTERNOON. SNOW AMOUNTS SHOULD
REMAIN ONE INCH OR LESS ACROSS THE AREA. STRONG WINDS HAVE BEEN
PERSISTENT IN THE ARLINGTON AREA THIS MORNING...BUT WINDS HAVE
BEEN SLOW TO RISE ALONG THE SOUTHERN LARAMIE RANGE...EASTERN
FOOTHILLS AND NEAR BORDEAUX. WILL LEAVE THE WIND HIGHLIGHT IN
PLACE...BUT EMPHASIZED THAT THE STRONG WINDS MAY NOT BE REALIZED
IN THESE AREAS FOR A FEW HOURS YET.

&&

.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 238 AM MST WED NOV 26 2014

RADAR SHOWS BAND OF LIGHT SNOW STRETCHING FROM NATRONA COUNTY
SOUTHEASTWARD INTO LARAMIE COUNTY. THIS BAND HAS LARGELY REMAINED
STATIONARY OVER THE PAST FEW HOURS...HOWEVER LIGHT SNOW IS
GENERALLY BEING OBSERVED WITH VISIBILITIES MOSTLY ABOVE 3SM. THE
MODELS HAVE THIS AREA OF SNOW CONTINUING THROUGH MID MORNING AND
THEN WEAKENING AND SHIFTING OFF TO THE NORTHEAST AS THE MID LEVEL
FRONTOGENESIS SHIFTS EASTWARD ALONG WITH THE UPPER JET. WILL
CONTINUE THE WINTER WEATHER ADVISORY THROUGH 21Z...EVEN THOUGH
ADDITIONAL ACCUMULATIONS WILL LIKELY BE AT MOST 1-2 INCHES. THE
SIERRA MADRE AND SNOWY RANGES HAVE PICKED UP SOME GOOD SNOW OVER
THE PAST 12 HOURS...WITH A FEW LOCATIONS GETTING 10-12 INCHES.
EXTENDED THE WINTER STORM WARNING THROUGH 21Z AS MOIST OROGRAPHICS
WILL CONTINUE INTO THE EARLY AFTN. SNOW REALLY COMES TO AN END
AREAWIDE BY LATE AFTN.

THE OTHER STORY WILL BE THE INCREASING WEST WINDS LATER TODAY ACROSS
SOUTHEAST WYOMING...ESPECIALLY WIND PRONE AREAS. THE 850MB CAG-CPR
GRADIENT IS CURRENTLY AT 35 METERS BUT IS PROGGED TO INCREASE TO
65 METERS BY 15Z AND THEN CONTINUE IN THE 55-65 METER RANGE ALL THE
WAY THROUGH THURS AFTN. 750MB WINDS INCREASE TO AROUND 50 KT ALONG
INTERSTATE 80 BY 18Z AND THE SFC PRESSURE TROUGH TRANSITIONS TO THE
EAST OF THE LARAMIE RANGE AT THIS TIME. THIS HAS THE LOOK OF A LONG
DURATION MARGINAL HIGH WIND EVENT WHERE THE WIND PRONE AREAS WILL
BE BOUNCING AROUND GUSTS OF 50-60 MPH. DEFINITELY NOT EXPECTING
GUSTS AS HIGH AS YESTERDAY...BUT DECIDED TO ISSUE A HIGH WIND
WARNING FOR THE WIND PRONE AREAS FROM 15Z TODAY THROUGH 15Z THURS.
GRADIENTS DO NOT CHANGE MUCH THROUGH FRI SO COULD SEE FUTURE
SHIFTS POTENTIALLY EXTENDING THIS. ALTHOUGH SNOW WILL HAVE LARGELY
ENDED BY LATE MORNING ACROSS ALBANY AND LARAMIE COUNTIES...BLOWING
SNOW COULD BE A CONCERN THROUGH THE EARLY AFTN. MAIN AREA OF CONCERN
WOULD BE THE SOUTHERN LARAMIE RANGE WHERE TEMPS WILL BE COLDER TO
PREVENT MELTING/CRUSTING OF THE SNOW AND WINDS WILL BE STRONGEST.

WARM ADVECTION DEVELOPS LATER TODAY AND ESPECIALLY BY TONIGHT AND
THURSDAY. IT WILL BE A MILD NIGHT OVER SOUTHEAST WY ESPECIALLY WITH
THE WINDS KEEPING THINGS MIXED. STILL HAVE TEMPS RISING INTO THE
UPPER 50S AND LOW 60S BY THANKSGIVING...SO IT WILL BE PLEASANT DAY
MINUS THE BREEZY TO WINDY CONDITIONS OVER SOUTHEAST WY.

.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 238 AM MST WED NOV 26 2014

MODERATE TO HIGH CONFIDENCE WITH 00Z/06Z MEDIUM RANGE MODEL GUIDANCE
PROGGING THE INTERMOUNTAIN WEST UPPER RIDGE TO DEAMPLIFY RESULTING
IN ZONAL FLOW ALOFT EARLY IN THE PERIOD. ANOTHER UPPER TROUGH
PIVOTS SOUTH AND EAST FROM BRITISH COLUMBIA ACROSS THE NORTHERN
ROCKIES AND PLAINS THIS WEEKEND. LEE SURFACE TROUGH DEEPENS
SATURDAY WITH PASSAGE OF A SHORTWAVE. THIS WILL RESULT IN A
DRY...MILD AND WINDY WEATHER PATTERN FRIDAY THROUGH SATURDAY.
STRONGEST WINDS ALOFT ARE PROGGED ALONG AND EAST OF THE LARAMIE
RANGE. LOOKING AT A PROLONGED HIGH WIND EVENT FOR SOUTHEAST WY AND
WIND ADVISORY CRITERIA FOR WESTERN NE. THE MODELS CONTINUE TO PROG
A ARCTIC FRONT PROGRESS SOUTH ACROSS WY/NE SUNDAY...WITH RAIN
CHANGING TO SNOW. AFTER HIGH TEMPERATURES IN THE 50S AND 60S
SATURDAY...SUNDAY`S HIGHS WILL BE IN THE 20S AND 30S. CONFIDENCE
THEN DECREASES EARLY NEXT WEEK WITH THE GFS/CANADIAN MODELS
BUILDING A UPPER RIDGE OVER THE GREAT BASIN BY MONDAY AND
TRANSLATING EAST ACROSS THE FRONT RANGE AND PLAINS TUESDAY.
CONVERSELY...THE ECMWF TRACKS ANOTHER UPPER TROUGH ACROSS WY AND
THE NORTHERN HIGH PLAINS TUESDAY. PRECIPITATION WILL MAINLY BE
CONFINED ALONG AND WEST OF THE LARAMIE RANGE MONDAY NIGHT AND
TUESDAY. TEMPERATURES EARLY NEXT WEEK MODERATE INTO THE 40S TO LOW
50S FOR THE PLAINS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1151 AM MST WED NOV 26 2014

LIGHT SNOW SHOWERS WILL CONTINUE OVER PORTIONS OF EXTREME SOUTHEAST
WY AND THE WESTERN NE PANHANDLE THROUGH ABOUT 20Z. EXPECT A GENERAL
OVC AROUND 5K FEET AGL WITH LOCALLY MVFR TO IFR CIGS/VSBYS IN A FEW
OF THE SNOW BANDS. VFR PROBABLE AFTER 20Z THIS AFTN AS THINGS BEGIN
TO CLEAR OUT. GUSTY WEST WINDS AROUND 40 KTS ARE EXPECTED TO PERSIST
AT KRWL AND KLAR THROUGH THE DAY.

&&

.FIRE WEATHER...
ISSUED AT 238 AM MST WED NOV 26 2014

MINIMAL FIRE WEATHER CONCERNS THROUGH THE END OF THE WEEK. LIGHT
SNOW WILL CONTINUE ACROSS PORTIONS OF SOUTHEAST WYOMING THROUGH THE
MORNING. MILDER TEMPERATURES ARE EXPECTED ON THURSDAY THROUGH
SATURDAY WITH MANY LOCATIONS AROUND 15 DEGREES ABOVE NORMAL. THE
WARMING TREND WILL CAUSE MINIMUM AFTERNOON HUMIDITY VALUES TO DROP
INTO THE 20-30 PERCENT RANGE FOR AREAS TO THE EAST OF THE LARAMIE
RANGE. WINDY CONDITIONS WILL PERSIST ACROSS SOUTHEAST WYOMING THROUGH
SATURDAY.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...HIGH WIND WARNING UNTIL 8 AM MST THURSDAY FOR WYZ106-110-116-117.

NE...NONE.
&&

$$

UPDATE...RJM
SHORT TERM...ZF
LONG TERM...MJ
AVIATION...CLH
FIRE WEATHER...ZF



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