FXUS63 KLBF 252044
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
244 PM CST FRI DEC 25 2009

.NEAR TERM...(TONIGHT THROUGH MONDAY)
FORECAST CHALLENGE IS SNOW AND WIND TONIGHT THROUGH NOON SATURDAY. 
AT 19Z THE IR SATELLITE LOOP SHOWS CLOUDS DEVELOPING WEST AS UPPER 
LOW LIFTS NORTHWEST TOWARD SOUTHWEST IOWA. COLDER CLOUD TOPS TO THE
WEST ASSOCIATED WITH TROWAL DEVELOPING SOUTHWEST THROUGH THE
NORTHERN AND CENTRAL PLAINS. AT 19Z THE SURFACE MAP SHOWED THE
LOW OVER NCNTRL IOWA WITH TIGHTLY PACKED GRADIENT ACROSS NEB WHERE
NORTHWEST WINDS ARE RANGING FROM 25 TO 35 KNOTS WITH THE HIGHEST
GUST SO FAR AT 51 KNOTS RECORDED AT VTN AT 1852Z. CURRENTLY THE
RADAR MOSAIC LOOP SHOWS RETURNS DEVELOPING SOUTHWEST ACROSS THE
FORECAST AREA WITH WIDESPREAD LIGHT TO MODERATE SNOWFALL. SNOWFALL
REPORTS INDICATE MINIMAL SNOW ACCUMULATION AS STRONG WINDS
CONTINUE TO CREATE SIGNIFICANT BLOWING AND DRIFTING OF THE SNOW.
HEADLINES WILL CONTINUE TONIGHT THROUGH NOON SATURDAY. MODELS SHOW
A SIMILAR TREND WITH SYSTEM TO FURTHER BACK NORTHWEST ACROSS
NORTHWEST IOWA THIS EVENING THEN LIFT NORTHEAST ON SATURDAY. WILL
TREND FORECAST TOWARD THE GFS SOLUTION THAT BRINGS SYSTEM FURTHEST
NORTHWEST THAT HOLDS ONTO THE STRONGER WINDS CLOSE TO MIDNIGHT. 

TONIGHT THE 285K SURFACE SHOWS STEADY ISENTROPIC LIFT WITH
SPECIFIC HUMIDITY INCREASING AS MOISTURE CHANNELS SOUTHWEST
THROUGH THE NORTHERN PLAINS. ENERGY CONTINUES TO ROTATES WEST THAT
WILL HELP KEEP THE SNOW FALLING TONIGHT. WWD/S SNOWFALL AMOUNTS
LOOK REASONABLE WITH AN ADDITIONAL 2 TO 4 INCHES OF ACCUMULATION
POSSIBLE OVERNIGHT WHILE WINDS SLOWLY DROP OFF OVERNIGHT. HEADLINES
RUN UNTIL 18Z SATURDAY WITH THE COMBINATION OF SNOWFALL OVERNIGHT
AND STRONG WIND GUSTS TO 30 KNOTS TO CONTINUE. TEMPERATURES OVERNIGHT WILL
DROP INTO THE SINGLE DIGITS TO LOW TEENS.

SATURDAY SYSTEM BEGINS TO FILL AS IT LIFTS NORTHEAST TOWARD THE 
LAKES. WINDS WILL FURTHER DROP OFF BUT DON/T EXPECT THE SNOW TO END 
UNTIL LIFT DIMINISHES SATURDAY EVENING AND THE DENDRITIC LAYER
BEGINS TO DRY OUT...WHERE THE SOUTHWEST MAY SEE THE SNOW TAPER TO
FLURRIES IN THE AFTERNOON THEN SNOW ENDING ACROSS THE NORTH SUNDAY
MORNING. TEMPERATURES FOR THE WEEKEND SLOWLY CLIMB WITH SNOW
COVER TO IMPEDE ANY REAL WARMUP. SUNDAY NIGHT CLEARING WILL LEAD
TO THE COLDEST TEMPERATURES WITH SUBZERO READINGS LIKELY TO START
THE DAY MONDAY.

.EXTENDED...
MUCH OF MID TO LATE NEXT WEEK WILL BE DOMINATED BY TROF ACROSS 
CENTRAL CONUS...LEAVING BELOW NORMAL TEMPERATURES IN THE PICTURE FOR 
SURE. MORE UNCERTAIN IS THE CHANCE OF PRECIPITATION WITH DIFFERING 
SOLNS OF MED RANGE MODELS. CONTINUED THE DRY FORECAST AS SOUTHERN 
STREAM SYSTEM RESPONSIBLE FOR FORMATION OF THE GENERAL TROF LOOKS TO 
TRAVERSE ACROSS SOUTHERN PLAINS ON TUESDAY LEAVING WESTERN NEBRASKA 
OUTSIDE PCPN SHIELD. BEHIND THIS SYSTEM STREAMS MERGE AND PHASE INTO 
THE LARGER CENTRAL CONUS TROF. IT IS THE HANDLING OF THE HIGH 
LATITUDE ENERGY IN ASSOC WITH H.BAY VORTEX WHERE MODEL SOLNS BEGIN 
TO DIVERGE. EURO MOST AGGRESSIVE PINWHEELING A SYSTEM ACROSS THE 
DAKOTAS AND CLOSING OFF SYSTEM IN THE MS VALLEY...GFS MORE 
PROGRESSIVE WITH MOST OF ENERGY REMAINING UP NEAR VORTEX AND OPEN 
TROF BRUSHES THE DAKOTAS AND GREAT LAKES REGION. 00Z GEM LOOKED TO 
BE COMPROMISE AND THERE MAY BE SMALL PCPN CHANCES TO ADD LATER. 
BIGGEST CHANGE ATTM THO WAS TO LOWER TEMPERATURES LATE WEEK WITH 
ANOTHER ARCTIC TAP DROPPING THROUGH WHEN THE SYSTEMS PHASE. 

.AVIATION...
HAZARDOUS FLIGHT CONDITIONS AT TERMINAL WILL CONTINUE THROUGH MUCH 
OF THE NEXT 12 TO 18 HOURS WITH SNOW...WIND GUSTS UP TO AN ABOVE 
40KTS AT TIMES...AND RESTRICTIONS TO VERTICAL AND HORIZONTAL VSBYS 
AS A RESULT. MOST WIND GUSTS AOA 40KTS HAVE BEEN ACCOMPANIED BY LIFR 
CONDITIONS WITH VSBYS AOB 1/4SM BLSN. CONDITIONS SHOULD SLOWLY 
IMPROVE THROUGH SUNRISE ON SATURDAY...BUT WINDY CONDITIONS COULD 
STILL LEAD TO RESTRICTIONS TO VSBY AND CIGS AS THIS SNOW IS LIGHT 
AND BLOWS AROUND EASY. SCATTERED SNOW SHOWERS WILL MOST LIKELY 
PERSIST THROUGH THE DAY...ESPECIALLY ACROSS NORTHERN NEBRASKA AND 
KVTN TERMINAL. KEPT WORSE CASE SCENARIO IN TAFS AT 18Z FORECAST AND 
WILL RE-EVALUTE THROUGH THE 00Z AND 06Z ISSUANCES FOR IMPROVEMENT. 

&&

.LBF WATCHES/WARNINGS/ADVISORIES...WINTER WEATHER ADVISORY UNTIL 
NOON CST /11 AM MST/ SATURDAY FOR NEZ022-056-058-069>071.

BLIZZARD WARNING UNTIL NOON CST /11 AM MST/ SATURDAY FOR 
NEZ005>010-023>029-035>038-057-059-094.

WINTER STORM WARNING UNTIL 11 AM MST SATURDAY FOR NEZ004.

&&

$$

SHORT TERM...KECK 
EXTENDED/AVIATION...13