FXUS65 KCYS 111038
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
338 AM MST THU MAR 11 2010

.SHORT TERM...TODAY THROUGH FRIDAY NIGHT...
TODAY...PRIMARY CHALLENGE WILL BE WIND SPEEDS...PARTICULARLY
ACROSS WESTERN NEBRASKA. SURFACE THROUGH 700 MB GRADIENTS WILL BE
RELATIVELY STRONG AND WITH 500-300 MB QG DOWNWARD MOTION COUPLET
THIS AFTERNOON...EXPECT STRONGER WINDS TO BE TRANSPORTED TO THE
SURFACE...THUS HAVE ISSUED A WIND ADVISORY FOR ALL OF WESTERN
NEBRASKA EXCEPT DAWES COUNTY. EXPECT 40 KNOT 700 MB WINDS TO BE
CAPABLE OF BEING TRANSPORTED TO THE SURFACE.

ISOLATED TO SCATTERED SNOW SHOWERS WILL DECREASE IN COVERAGE THIS
AFTERNOON AS LOW AND MID LEVEL MOISTURE WANES AND THE UPPER TROUGH
MOVES FURTHER EAST ACROSS THE MIDWEST STATES.

TONIGHT...DRY WITH LACK OF LOW AND MID LEVEL MOISTURE AND LIFT.
WINDS WILL SUBSIDE IN THE EVENING WITH SOME DECOUPLING AND
RELAXATION OF GRADIENTS.

FRIDAY...WARMER DAY ON TAP WITH HIGH TEMPERATURES IN THE 40S TO
LOWER 50S WITH 1000-500 MB THICKNESSES NEAR 5490 METERS AND 700 MB
TEMPERATURES NEAR -4 CELSIUS.

FRIDAY NIGHT...TRANSITORY SHORTWAVE RIDGE MOVES ACROSS WYOMING
KEEPING OUR WEATHER DRY.

.LONG TERM...SATURDAY THROUGH THURSDAY...
A BROAD REX BLOCK DOWNSTREAM WILL IMPACT THE PATTERN PROGRESSION
ACROSS THE WRN CONUS THIS WEEKEND...BEFORE THE PATTERN TURNS MORE
PROGRESSIVE NEXT WEEK. INITIALLY...AN UPPER RIDGE AXIS WILL BE
CENTERED OVER THE INTERMOUNTAIN WEST ON SATURDAY...AS THE REGION
IS CAUGHT BETWEEN A LARGE UPPER LOW TO THE EAST...AND AN
APPROACHING TROUGH MOVING ONTO THE PACIFIC COAST. SO...SATURDAY
WILL BE DRY...WITH TEMPERATURES MODERATING INTO THE 40S...WITH LOW
TO MID 50S IN LOWER ELEVATIONS EAST OF THE MOUNTAINS. CLOUDS WILL
SLOWLY BE ON THE INCREASE...ESPECIALLY LATE SATURDAY...AS THE WEST
COAST TROUGH SPLITS SENDING A PIECE OF ENERGY NORTH...AND AN
EVENTUAL CUT-OFF LOW SOUTH OF THE AREA. GIVEN THE PROXIMITY OF THE
SYNOPTIC FORCING ASSOCIATED WITH THE SOUTHERN CUT-OFF LOW...HAVE
ADDED SOME SLIGHT POPS TO THE MOUNTAINS LATE SATURDAY NIGHT...AND
TO ALL LOWER ELEVATIONS WEST OF THE MOUNTAINS ON SUNDAY. THERE
WILL NOT BE MUCH MOISTURE TO WORK WITH...SO EXPECT ANY SNOW TO
REMAIN VERY LIGHT. THE SOUTHERN STREAM ENERGY WILL DRIFT SOUTH AND
BY SUNDAY NIGHT A DRIER AIR MASS WILL BE IN PLACE. BY MONDAY...THE
BEGINNING OF THE NEXT QUIET PERIOD WILL BE UPON THE AREA...AS THE
NEXT UPPER RIDGE WILL BUILD OVER THE INTERMOUNTAIN WEST. THIS
UPPER RIDGE WILL MAINTAIN DRY CONDITIONS MONDAY THROUGH WEDNESDAY
NIGHT. TEMPERATURES WILL ALSO BE QUITE MILD AS 700MB TEMPERATURES
REACH FREEZING...WHICH WOULD YIELD 60F AT 5 KFT FULLY MIXED. HAVE
KEPT TEMPERATURES AROUND THE MEAN ENSEMBLES...BUT EVEN THESE MAY NEED
TO BE BUMPED UP SOME...ESPECIALLY IF THESE WARM 700MB TEMPS ARE
REALIZED. BOTH THE ECMWF/GFS ARE SUGGESTING THE NEXT SYSTEM WILL
MOVE IN NEXT THURSDAY...SO FOR NOW HAVE INTRODUCED CLIMO POPS
ACROSS THE AREA.

&&

.AVIATION...
INITIALLY...MVFR CIGS/VSBYS CAN BE EXPECTED AT ALL TERMINALS AT
LEAST FOR A FEW HOURS THIS MORNING. A GRADUAL RETURN TO VFR IS
EXPECTED FROM WEST TO EAST THROUGH THE DAY. MVFR CONDITIONS WILL
LINGER THE LONGEST AT NEBRASKA AIRPORTS...WHICH MAY NOT RETURN TO
VFR UNTIL LATE THIS AFTERNOON. OTHERWISE...NORTHWEST WINDS RAMP UP
TODAY...WITH 25 TO 35 MPH WITH GUSTS AT HIGH AS 45 MPH EXPECTED
FOR LOCATIONS EAST OF THE MOUNTAINS. THIS WILL CREATE TURBULENCE
ESPECIALLY IN AND AROUND THE MOUNTAINS TODAY. WINDS WILL SUBSIDE
SOME OVERNIGHT...BUT ANOTHER WINDY DAY IS EXPECTED ON FRIDAY.

&&

.FIRE WEATHER...
NO FIRE WEATHER CONCERNS THROUGH FRIDAY NIGHT.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...WIND ADVISORY FROM 7 AM THURSDAY TO 5 PM THURSDAY FOR NEZ003-
NEZ019-NEZ020-NEZ021-NEZ054-NEZ055-NEZ095-NEZ096.

&&

$$

SHORT TERM/AVIATION...RUBIN
LONG TERM...HAHN

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