FXUS63 KLBF 242101
AFDLBF
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
302 PM CST THU DEC 24 2009
.DISCUSSION...
A TANDEM OF UPPER LEVEL LOWS CONTINUE TO SPIN ACROSS THE CENTRAL
CONUS THIS AFTERNOON. A SRN STREAM SYSTEM WAS LOCATED OVER NERN TX
AND A SECOND WAS NORTHWEST OF THE BLACK HILLS. AT THE SURFACE...LOW
PRESSURE WAS LOCATED OVER NWRN ARKANSAS...WITH ARCTIC HIGH PRESSURE
LOCATED OVR WRN SODAK AND ERN MT. PRESSURE GRADIENT HAS RELAXED THIS
AFTERNOON ACROSS WESTERN NEBRASKA...WITH WINDS GENERALLY IN THE 15
TO 25 MPH RANGE. FURTHER EAST...WINDS WERE MUCH STRONGER OVER
EASTERN NEBRASKA WITH SOME STATIONS REPORTING WIND GUSTS TO 40
MPH.
.DISCUSSION...
NEAR TERM...TONIGHT THROUGH SUNDAY NIGHT...MAIN FORECASTING
CHALLENGE OVER THE NEXT 24 TO 48 HOURS IS HOW TO HANDLE
HEADLINES...SNOW ACCUMULATIONS AND WINDS. AS MENTIONED BEFORE...TWO
DISTINCT CIRCULATIONS NOTED ATTM WITH THE SRN STREAM LOW LIFTING
NORTH...THEN MERGING WITH THE NRN STREAM LOW OVER THE MID
MISSISSIPPI VALLEY ON FRIDAY. SURFACE LOW WILL TRACK NORTH FROM THE
ARKLATEX INTO IA TONIGHT AND FRIDAY. SECOND ARCTIC HIGH WILL BUILD
SOUTH ALONG THE HI PLAINS OF WYOMING AND MT INTENSIFYING THE
PRESSURE GRADIENT OVER NEBR FRIDAY MORNING. H85 WINDS APPROACH 60
KTS FRIDAY AND FRIDAY EVENING OVER THE NORTHEAST AND NERN
ZONES...AND HAVE DECIDED TO HOIST A BLIZZARD WARNING FOR FRIDAY AND
FRIDAY NIGHT...BASED ON THIS AND MAV GUIDANCE WINDS IN THE MID 30S
AT ANW...ONL...AND BRIEFLY AT VTN. CHERRY COUNTY SOMEWHAT IN DOUBT
WINDS WILL BE STRONGEST IN NERN SECTIONS OF THE COUNTY AND FEEL WE
CANNOT IGNORE THE WIND POTENTIAL HERE. FURTHER WEST OVER SHERIDAN
COUNTY...DECIDED TO KEEP THE WINTER STORM WARNING AS IS FOR
NOW...BASED ON LOWER WIND SPEEDS PER MAV AND GRAPHICAL FORECAST
GUIDANCE. SOUTH OF THE BLIZZARD WARNING...KEPT THE WINTER STORM
WARNING IN EFFECT AND ADDED UPGRADED LOGAN AND CUSTER COUNTY TO A
WINTER STORM WARNING BASED EXISTING SNOW COVER (STAPLETON REPORTED
2.6 INCHES...ANSELMO 2.0 INCHES AND 1.5 IN BROKEN BOW) AND WIND
POTENTIAL...EVEN THOUGH SNOW ACCUMS WILL BE IN THE 2 TO 4 INCH
RANGE.
GIVEN THE SLOWER EWD MOVEMENT OF THE SYSTEM...WINDY CONDITIONS
CONTINUING INTO SATURDAY MORNING...AND THE CONTINUING THREAT FOR
LIGHT SNOW...WILL EXTEND ALL HEADLINES INTO MIDDAY SATURDAY. THROUGH
SATURDAY MORNING...HEAVIEST ACCUMULATIONS STILL APPEAR TO BE OVER
THE NORTHEASTERN ZONES WHERE 7 TO 10 INCH AMOUNTS ARE EXPECTED IN
THE NORTHEASTERN FOUR COUNTIES...DECENT LIGHT WRAPAROUND SNOW WILL
PUSH SOUTH INTO THE NRN CWA TOWARD FRIDAY MORNING...SPREADING SOUTH
TO ENCOMPASS MOST OF WESTERN AND NORTH CENTRAL NEBRASKA BY FRIDAY
AFTERNOON. SNOW WILL TAPER OFF TO FLURRIES ON SATURDAY...WITH WINDS
DECREASING BY MIDDAY.
LONG TERM...MONDAY THROUGH THURSDAY...
QUIET WEATHER EXPECTED TO START THE WORK WEEK. DEEP TROUGH OVER THE
FAR WESTERN STATES...WILL ALLOW FOR WEAK RIDGE TO DEVELOP OVER THE
CENTRAL PLAINS PRODUCING DRY CONDITIONS. SNOW PACK GOING TO KEEP
TEMPS BELOW NORMAL...AND HAVE GONE WITH HIGHS ONLY IN THE
20S...SLIGHTLY BELOW GUIDANCE. LONG RANGE MODELS IN SOME AGREEMENT
AS WEST COAST TROUGH TO DIG ACROSS THE SOUTHERN STATES BY MIDWEEK.
ECMWF WRAPS MORE MOISTURE INTO THE HIGH PLAINS...HOWEVER THE GFS HAS
A DRIER SOLUTION. THUS HAVE HELD OFF ON INTRODUCING POPS SO
FAR...BUT SOUTHERN PARTS OF THE STATE WILL NEED TO BE MONITORED AS
WE APPROACH ANOTHER HOLIDAY.
&&
.AVIATION...
VFR WITH SUNNY SKIES HAS BEEN WIDESPREAD OVER WESTERN NEBRASKA
TODAY. CENTRAL PARTS OF THE STATE HAVE SEEN A FEW FLURRIES...WITH
VFR CLOUDS. AS THE DEEP LOW LIFTS TO THE EAST...CONDITIONS DROP BACK
TO IFR AS WRAP AROUND MOISTURE RETURNS TO THE REGION. EXPECT SNOW TO
REDEVELOP OVERNIGHT...HOWEVER SNOW TO BE LIGHT TO BRIEFLY MODERATE.
GUSTY NORTHWEST WINDS TO THE BE THE MAIN PROBLEM...AS WIDESPREAD
GUSTS TO 35+KTS CONTINUE INTO TOMORROW. VSBY TO BE REDUCED BY SNOW
AND MORE SO BY THE BLOWING SNOW...AT TIMES TO LESS THAN 1SM.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
BLIZZARD WARNING ZONES NEZ005>010-027>029-094 FROM MIDNIGHT CST
TONIGHT THROUGH NOON CST SATURDAY.
WINTER STORM WARNING CONTINUES IN EFFECT THROUGH MIDNIGHT CST TONIGHT FOR
ZONES NEZ005>010-027>029-094.
WINTER WEATHER ADVISORY CONTINUES IN EFFECT THROUGH MIDNIGHT CST FOR
ZONES NEZ037-038.
WINTER STORM WARNING IN EFFECT FROM MIDNIGHT CST TONIGHT THROUGH
NOON CST SATURDAY FOR ZONES NEZ037-038.
WINTER STORM WARNING CONTINUES IN EFFECT THROUGH NOON CST SATURDAY
FOR ZONES NEZ004-023>026.
WINTER WEATHER ADVISORY CONTINUES IN EFFECT THROUGH NOON CST
SATURDAY FOR ZONES NEZ022-035-036-056>059-069>071.
$$
.SHORT TERM...BUTTLER
.AVIATION AND LONG TERM...MASEK