Area Forecast Discussion
Issued by NWS Cheyenne, WY

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668
FXUS65 KCYS 051139
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
439 AM MST FRI FEB 5 2016

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 300 AM MST FRI FEB 5 2016

FORECAST CHALLENGES WITH THIS PACKAGES DEALS PRIMARILY WITH WINDS.
HEADLINES WILL BE NEEDED FOR MANY AREAS. TIMING AND LOCATION OF
STRONG WINDS THE CHALLENGE.

CURRENTLY...SURFACE LOW PRESSURE OVER WESTERN NORTH DAKOTA THIS
MORNING WITH A 1040MB SURFACE HIGH OVER NORTHWESTERN COLORADO
BEING ANALYZED ON THE SURFACE ANALYSIS. COLD FRONT WASHING OUT
ACROSS OUR EASTERN ZONES. STILL GETTING A FEW REPORTS OF LIGHT
SNOW BEING REPORTED ON AREA METARS...BUT FOR THE MOST PART THESE
REPORTS CONFINED TO MOUNTAINOUS AREAS. BULK OF SNOW ON MOSAIC
RADAR HAS SHIFTED SOUTH INTO EASTERN COLORADO EARLY THIS MORNING.

ELSEWHERE...DEEP LOW PRESSURE SYSTEM CURRENTLY OFF THE COAST OF
WASHINGTON STATE CONTINUES TO MOVE EASTWARD. THIS IS THE SYSTEM
THAT WILL BRING OUR STRONG WINDS LATER TODAY INTO THE WEEKEND.

FOR TODAY...A PRETTY NICE DAY AS CLOUDS ASSOCIATED WITH FRONTAL
SYSTEM SHIFT EAST. SHOULD SEE CLEARING SKIES AS THE DAY
PROGRESSES. 700MB WINDS GRADUALLY SHIFTING MORE WESTWARD AND
INCREASING IN SPEEDS SHOULD ADD A DOWNSLOPE COMPONENT TO
TEMPERATURES EAST OF THE LARAMIE RANGE. MID 30S EXPECTED IN THE
PANHANDLE FOR HIGHS TODAY WITH MID 20S WEST.

700MB WINDS REALLY BEGIN RAMPING UP THIS EVENING. BY 06Z
TONIGHT...LOOKING AT 40-45KTS ACROSS CARBON AND ALBANY
COUNTIES...THEN UP TO 50-55KTS BY 12Z. SEE CRAIG TO CASPER
850/700MB HEIGHT GRADIENTS INCREASE TO 52/39 MTRS BY 03Z AND THEN
65/43MTRS BY 06Z. DO BELIEVE STRONG WINDS WILL BE A LITTLE LATER
THAN WHAT WE HAD GOING IN THE WATCH...SO WITH THE UPGRADE THIS
MORNING...STARTED THE WARNINGS FOR THE WIND PRONE AREAS AT 06Z.

CONCERNS THAT THE DAY SHIFT HAD ABOUT A MORE WIDESPREAD WIND EVENT
ARE SHARED THIS MORNING. THE 00Z GFS 700MB WINDS HAVE INCREASED TO
70KTS ACROSS ALBANY COUNTY AND ACROSS THE LARAMIE RANGE. NAM
700MB WINDS ARE NOT FAR BEHIND WITH 60KTS SATURDAY AFTERNOON. WENT
AHEAD WITH A HIGH WIND WATCH FOR MOST OF CARBON COUNTY...ALL OF
ALBANY COUNTY...WESTERN CONVERSE COUNTY AND THE REST OF PLATTE
COUNTY AS A RESULT. BOTH THE GFS AND NAM MOS GUIDANCE SHOWING 30KT
SUSTAINED WINDS ON GUIDANCE FOR RAWLINS...LARAMIE...DOUGLAS. FOR
THIS FORECASTER...THAT IS USUALLY A GOOD SIGN THAT THEY WILL HIT
WARNING CRITERIA. DAY SHIFT CAN TAKE ANOTHER LOOK AT THE 12Z MODEL
GUIDANCE TO NAIL DOWN TIMING AND ZONES FOR UPGRADE.

BY SATURDAY EVENING...UPPER LOW TRACKS INTO EASTERN MONTANA AND
WINDS SHOULD BEGIN EASING FOR SOUTHEAST WYOMING. HOWEVER...THAT IS
NOT THE CASE FOR THE NEBRASKA PANHANDLE. NAM 850MB WINDS INCREASE
TO 45-50KTS SUNDAY MORNING. AT THE VERY LEAST...WE ARE GOING TO
NEED WIND ADVISORIES OUT THERE FROM LATE SATURDAY NIGHT INTO
SUNDAY MORNING. DO GO HIGH ON WINDS OUT IN THE PANHANDLE FOR THE
SATURDAY NIGHT/SUNDAY TIMEFRAME.

.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 AM MST FRI FEB 5 2016

SUNDAY NIGHT...FAST MOVING NORTH NORTHWEST FLOW ALOFT WILL COMBINE
WITH LOW LEVEL GRADIENTS TO PRODUCE A BREEZY TO WINDY
NIGHT...ESPECIALLY OVER WESTERN NEBRASKA. LIMITED LOW AND MID LEVEL
MOISTURE WILL KEEP IT DRY.

MONDAY...CONTINUED WARMING TREND AS HEIGHTS AND THICKNESSES
SLOWLY RISE...THOUGH TEMPERATURES WILL BE LIMITED SOMEWHAT BY
NORTH NORTHWEST FLOW ALOFT.

TUESDAY...AIRMASS CONTINUES TO MODERATE LEADING TO RISING
TEMPERATURES...ESPECIALLY EAST OF THE INTERSTATE 25
CORRIDOR...WHILE COOL AIR REMAINS TRAPPED IN THE VALLEYS WEST OF
THE LARAMIE RANGE... THOUGH SEEING SOME MODERATION IN TEMPERATURES
IN THESE LOCATIONS AS WELL.

WEDNESDAY...ALTHOUGH NORTHWEST FLOW ALOFT PREVAILS...RISING HEIGHTS
AND THICKNESSES AND THE ABSENCE OF CLOUD COVER WILL AID IN A RATHER
MILD DAY BY FEBRUARY STANDARDS...WITH UPPER 30S TO MID 40S AT LOWER
ELEVATIONS WEST OF I-25...AND MID 40S TO LOWER 50S EAST OF I-25.

THURSDAY...SLIGHTLY COOLER WITH AN INCREASE IN MID AND HIGH LEVEL
CLOUD COVER. LOW AND MID LEVEL GRADIENTS SUGGEST IT WILL BE LESS
WINDY THAN TUESDAY OR WEDNESDAY.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 436 AM MST FRI FEB 5 2016

NEBRASKA TAFS...VFR. SCATTERED TO BROKEN CLOUDS AT OR ABOVE
6000 FEET AGL. GUSTS TO 32 KNOTS THROUGH 01Z.

WYOMING TAFS...VFR. SCATTERED TO BROKEN CLOUDS AT OR ABOVE
4000 FEET AGL. WEST TO SOUTHWEST WINDS GUSTING 25 TO 35 KNOTS.

&&

.FIRE WEATHER...
ISSUED AT 300 AM MST FRI FEB 5 2016

STRONG WINDS RETURN TO SOUTHEAST WYOMING AND ARE LIKELY TO BECOME
WIDESPREAD ACROSS THE AREA SATURDAY. HIGH WIND WARNINGS HAVE BEEN
POSTED FOR THE WIND PRONE AREAS OF SOUTHEAST WYOMING FOR WIND
GUSTS IN EXCESS OF 70 MPH WITH HIGH WIND WATCHES FOR MANY OF THE
LOWER AREAS SATURDAY. THESE WINDS WILL SPREAD OUT INTO THE
NEBRASKA PANHANDLE SATURDAY NIGHT INTO SUNDAY AND WIND HEADLINES
WILL LIKELY BE NEEDED OUT THERE AS WELL. WITH AN ABUNDANT SNOW
PACK THOUGH...FIRE WEATHER CONCERNS SHOULD BE MINIMAL.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...HIGH WIND WARNING FROM 8 PM THIS EVENING TO 11 PM MST SATURDAY
     FOR WYZ106-110-116-117.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH SATURDAY EVENING
     FOR WYZ101-104-105-107-109-115.

NE...NONE.
&&

$$

SHORT TERM...GCC
LONG TERM...RUBIN
AVIATION...RUBIN
FIRE WEATHER...GCC



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