Winter Storm Watch 1, NWS Cheyenne, WY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1058 PM MST FRI JAN 15 2016

.UPDATE...
ISSUED AT 818 PM MST FRI JAN 15 2016

THE BAND OF SNOW WHICH AFFECTED CHEYENNE AND THE SUMMIT EARLIER
THIS EVENING HAS SHIFTED OUT OF THE AREA. A FEW LINGERING FLURRIES
STILL POSSIBLE THE NEXT SEVERAL HOURS BUT THE NEXT MAIN CHANCE
FOR MEASURABLE SNOW WILL HOLD OFF UNTIL TOMORROW NIGHT AS SLIGHTLY
STRONGER DISTURBANCE MOVES OVER THE AREA.

UPDATE ISSUED AT 548 PM MST FRI JAN 15 2016

HERE IS A QUICK UPDATE ON THE SNOW BAND MOVING ACROSS THE LARAMIE
TO CHEYENNE AREA. THE SNOW BAND WHICH LIKELY DROPPED A FEW INCHES
OF SNOW OVER THE SUMMIT BETWEEN CHEYENNE AND LARAMIE IS
DECREASING IN INTENSITY AND SHIFTING SOUTH INTO COLORADO. THIS
TREND WILL CONTINUE OVER THE NEXT HOUR OR TWO WITH SNOW ENDING
SHORTLY THEREAFTER. ADDITIONAL SNOW ACCUMULATIONS WILL ONLY BE A
FEW TENTHS OF AN INCH. ROADS HAVE BECOME SLIPPERY DUE TO THE
FALLING SNOW AND WILL LIKELY REMAIN SLIPPERY THROUGH TONIGHT. SNOW
WILL CONTINUE TO FALL OVER THE SNOWY AND SIERRA MADRE RANGES THROUGH
THE EVENING WITH SNOW TAPERING OFF AFTER MIDNIGHT. ANOTHER ROUND
OF SNOW IS LIKELY OVER THE MOUNTAINS STARTING TOMORROW AFTERNOON.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 239 PM MST FRI JAN 15 2016

MODELS CONTINUE TO STRUGGLE WITH THE PLACEMENT OF SEVERAL BANDS OF
PRECIPITATION IN THE SHORT TERM...IN ADDITION TO THE ARCTIC FRONT
SATURDAY/SATURDAY NIGHT AND HOW FAR WEST IT STALLS. FOR THIS
AFTERNOON...SNOW IS GRADUALLY TAPERING OFF TO SNOW FLURRIES
ACROSS CARBON COUNTY AFTER THE LOCALLY HEAVY SNOW SHOWERS FROM
EARLIER THIS MORNING. EXPECT A BRIEF LULL INTO LATE THIS AFTERNOON
BEFORE A VORTICITY MAX ASSOCIATED WITH AN UPPER LEVEL DISTURBANCE
PUSHES SOUTHEAST ACROSS SOUTHEAST WYOMING THIS EVENING. THERE IS
SOME GOOD LLVL INSTABILITY FOR THIS TIME OF THE YEAR AS WELL AS
SOME FRONTOGENESIS ALONG THE LARAMIE RANGE...AND ALONG AND SOUTH
OF I80. THE TRICKY PART IS...IF THIS BAND OF SNOW DEVELOPS FURTHER
SOUTH INTO COLORADO...THE I80 CORRIDOR MAY RECEIVE NOTHING OUTSIDE
OF A FEW FLURRIES. INCREASED POP BETWEEN 40 TO 80
PERCENT...HIGHEST IN THE MOUNTAINS. WILL NEED TO KEEP AN EYE ON
THE I80 SUMMIT AS WELL AS LARAMIE AND CHEYENNE FOR ACCUMULATING
SNOW AND SOME IMPACTS TO ROADS THIS EVENING. SOME OF THESE SNOW
BANDS MAY BE MODERATE TO HEAVY AT TIMES IN INTENSITY.

SATURDAY...ARCTIC FRONTAL BOUNDARY STILL PROJECTED TO MOVE
SOUTHWARD AND JAM UP EAST OF THE LARAMIE RANGE ON SATURDAY. DECENT
FRONTAL FORCING ALONG AND EAST OF THE LARAMIE RANGE WITH AMPLE
MOISTURE AND INSTABILITY EXPECT TO GET A FAIRLY DECENT COVERAGE OF
SNOW SHOWERS IN BANDS ACROSS SOUTHEAST WYOMING AND EAST INTO THE
NEBRASKA PANHANDLE SATURDAY INTO SATURDAY NIGHT AS ANOTHER
SHORTWAVE MOVES THROUGH. OUT WEST FAVORABLE ACTIVE NORTHWESTERLY
FLOW WITH UPSLOPE WILL KEEP SNOW GOING IN THE MOUNTAINS WELL INTO
THE WEEKEND. AN ADDITIONAL 12 TO 18 INCHES OF SNOW CAN BE EXPECTED
FOR A 3 DAY WEEKEND TOTAL ABOVE 9500 FT IN THE SIERRA MADRE RANGE
WITH 8 TO 12 INCHES ABOVE 9500 FT FOR THE SNOWY RANGE. LOWER 24
HOUR TOTALS IN THE MOUNTAINS WILL KEEP THE EVENT IN THE ADVISORY
CATEGORY. WILL NEED TO MONITOR FOR POSSIBLE ADDITION OF A WINTER
WEATHER ADVISORY FOR THE SNOWY RANGE AS WELL FOR SATURDAY INTO
SUNDAY.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 239 PM MST FRI JAN 15 2016

SNOW SHOWERS TAPER OFF BY SUNDAY AFTERNOON IN THE LOWER ELEVATIONS
WITH SNOW CONTINUING IN THE MOUNTAINS THROUGH WEDNESDAY GIVEN
FAVORABLE AND ACTIVE MIDLEVEL FLOW. AFTER A COUPLE OF SHORTWAVES
MOVE THROUGH MONDAY INTO WEDNESDAY...IT APPEARS WE DRY OUT
SUFFICIENTLY TO NEGATE POPS THURSDAY INTO NEXT WEEKEND AS A
RATHER LARGE AMPLITUDE MID/UPPER RIDGE TRAVERSES THE
CENTRAL/NORTHERN ROCKIES.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1050 PM MST FRI JAN 15 2016

VFR ACROSS A MAJORITY OF THE FORECAST AREA TONIGHT THROUGH
SATURDAY MORNING. AS OF 06Z LOW STRATUS WAS OCCURRING AROUND
ALLIANCE NEBRASKA BUT THAT WILL LIKELY ERODE OVER THE NEXT
SEVERAL HOURS. A FEW LIGHT SNOW SHOWERS ARE STILL OCCURRING OVER
THE MOUNTAINS OF SOUTHEAST WYOMING WHICH WILL PRODUCE VISIBILITY
AND CEILING RESTRICTIONS IN THOSE AREAS.

WHILE THE SNOW WILL TAPER OFF OVER THE MOUNTAINS
TONIGHT...ANOTHER DISTURBANCE WILL MOVE OVER THE FORECAST AREA
LATE SATURDAY INTO SUNDAY MORNING. WIDESPREAD LIGHT SNOW WILL
FALL OVER MUCH OF SOUTHEAST WYOMING AND INTO THE WESTERN NEBRASKA
PANHANDLE. WINDS WILL ALSO INCREASE...ESPECIALLY OVER THE WIND
PRONE AREAS IN SOUTHEAST WYOMING. FALLING SNOW WITH GUSTS TO 50
MPH CAN BE EXPECTED LATE SATURDAY NIGHT INTO THE WIND PRONE AREAS
SUCH AS AROUND VEDAUWOO AND ARLINGTON.

&&

.FIRE WEATHER...

NO FIRE WEATHER CONCERNS ARE EXPECTED AT THIS TIME DUE TO SNOW
COVER IN PLACE AND COLDER AIR MOVING INTO AREAS EAST OF THE
LARAMIE RANGE SATURDAY NIGHT INTO SUNDAY.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 5 AM MST SATURDAY FOR WYZ112.

NE...NONE.

&&

UPDATE...SML
SHORT TERM...TJT/JG
LONG TERM...JG
AVIATION...SML
FIRE WEATHER...REC