Area Forecast Discussion
Issued by NWS Cheyenne, WY

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS65 KCYS 191015
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
415 AM MDT FRI SEP 19 2014

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 415 AM MDT FRI SEP 19 2014

PREDAWN WATER VAPOR/H5 COMPOSITE ANALYSIS DEPICTED A UPPER RIDGE
AXIS FROM THE SOUTHERN ROCKIES TO THE NORTHERN GREAT PLAINS. A
NORTHERN STREAM MID LEVEL TROUGH WAS MOVING ACROSS THE NORTHERN
ROCKIES...WITH A MORE SUBSTANTIAL TROUGH AND UPPER LOW IMPACTING
CALIFORNIA. MOIST UNSTABLE AIR INTERACTING WITH A NE-SW SURFACE
FRONT BISECTING WY PRODUCED SCATTERED SHOWERS/TSTORMS ACROSS
SW...CENTRAL AND NE WY. THE LEADING EDGE OF THIS PRECIPITATION
WILL MOVE TO A RAWLINS-DOUGLAS LINE EARLY THIS MORNING.

THE UPPER RIDGE FLATTENS AND MOVES INTO THE CENTRAL PLAINS AS
THE MID LEVEL TROUGH MOVES THROUGH THE NORTHERN PLAINS TODAY. THE
FRONT TO THE NORTHWEST WILL ADVANCE SOUTHEAST ACROSS THE CWA THIS
MORNING WITH WINDS SHIFTING TO THE NORTH AND NORTHEAST. AFTER
RECORD OR NEAR RECORD WARMTH YESTERDAY...TODAY WILL BE SLIGHTLY
COOLER WITH HIGHS IN THE MID TO UPPER 80S EAST OF THE LARAMIE
RANGE AND 60S AND 70S WEST. SCATTERED SHOWERS/TSTORMS WILL
EVENTUALLY SPREAD EAST ACROSS SOUTHEAST WY THIS AFTERNOON WITH
MAINLY ISOLATED COVERAGE OVER WESTERN NE THIS EVENING.

NORTHWEST FLOW ALOFT IN THE WAKE OF THE DEPARTING TROUGH WILL
USHER IN A DRIER MORE STABLE AIRMASS TONIGHT AND SATURDAY.
WEAK UPSLOPE LOW LEVEL FLOW AND INSTABILITY MAY RESULT IN A
FEW AFTERNOON SHOWERS OR TSTORMS FOR THE SOUTHEAST WY MOUNTAINS.
700MB TEMPERATURES COOL FROM 12C THIS AFTERNOON TO 9C SATURDAY
AFTERNOON. HIGHS WILL RANGE FROM THE 50S/60S MOUNTAINS TO THE
70S AND LOWER 80S VALLEYS AND PLAINS.

UPPER LOW AND ASSOCIATED TROUGH OVER CA MOVES SLOWLY NE ACROSS
NV/UT SUNDAY. SUBTROPICAL MOISTURE WILL LIKEWISE SPREAD NE INTO
SOUTHERN WY DURING THE DAY WITH PRECIPITABLE WATER VALUES
APPROACHING AN INCH. DIFFLUENT FLOW ALOFT AND LOW LEVEL SOUTHEAST
UPSLOPE FLOW WILL RESULT IN SCATTERED SHOWERS/TSTORMS MAINLY ALONG
AND SOUTH OF THE I-80 CORRIDOR IN WY WITH ISOLATED COVERAGE EAST
INTO THE SOUTHERN NE PANHANDLE. IT WILL BE 3-5 DEGREES COOLER
SUNDAY WITH HIGHS IN THE 50S/60S MOUNTAINS TO THE 70S LOWER
ELEVATIONS.

.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 405 AM MDT FRI SEP 19 2014

SUNDAY NIGHT/MONDAY...ISOLATED TO SCATTERED SHOWERS AND ISOLATED
EVENING THUNDERSTORMS POSSIBLE SUNDAY NIGHT IN THE DIFFLUENT FLOW
ALOFT. AS THE SHORTWAVE TROUGH MOVES OVERHEAD ON MONDAY...WILL
SEE MORE SHOWERS AND THUNDERSTORMS ERUPT.

TUESDAY...SHORTWAVE TROUGH ALOFT MOVES FURTHER AWAY...THUS ONLY
ISOLATED TO WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ON TAP IN
THE MOIST FLOW ALOFT.

WEDNESDAY/THURSDAY...WARMING AND DRYING TREND CONTINUES AGAIN WITH
THE LOW AND MID LEVELS AGAIN WARMING SLOWLY...AND RIDGING ALOFT
WILL KEEP IT DRY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY EVENING)
ISSUED AT 1122 PM MDT THU SEP 18 2014

SYNOPTICALLY...A WEATHER DISTURBANCE WILL MOVE ACROSS EASTERN
MONTANA AND THE WESTERN DAKOTAS THE REST OF THE NIGHT...SENDING
A WEAK SURFACE TROUGH TO A RAPID CITY TO CHEYENNE LINE BY DAWN...
THEN LOW LEVEL WINDS WILL TURN NORTH AND NORTHWEST AFTER DAYBREAK
FRIDAY.

WYOMING AERODROMES...VFR PREVAILS WITH SCATTERED TO BROKEN CLOUDS
AT OR ABOVE 10000 FEET AGL. ISOLATED THUNDERSTORMS NEAR THE
RAWLINS AND CHEYENNE SITES...FROM 11Z TO 17Z AT RAWLINS...AND
AFTER 21Z AT CHEYENNE.

NEBRASKA AERODROMES...VFR PREVAILS WITH SCATTERED TO BROKEN CLOUDS
AT OR ABOVE 10000 FEET AGL.

&&

.FIRE WEATHER...
ISSUED AT 324 AM MDT FRI SEP 19 2014

A WEAK PACIFIC COLD FRONT WILL PROGRESS EAST THROUGH THE DISTRICTS
TODAY WITH ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS AND
COOLER TEMPERATURES. A DRIER AIRMASS WILL PREVAIL SATURDAY. THE
NEXT CHANCE FOR WETTING RAINFALL WILL BE SUNDAY THROUGH TUESDAY
FROM A SLOW MOVING UPPER LOW PRESSURE SYSTEM. WINDS DURING THE
FORECAST PERIOD WILL BE LIGHT...EXCEPT IN THE VICINITY OF
THUNDERSTORMS.

&&

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

$$

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



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.