FXUS63 KBIS 251630
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
1030 AM CST FRI DEC 25 2009

.UPDATE...

FORECAST SEEMS ON TRACK. UPDATED FOR AESTHETICS BASED ON LATEST
REGIONAL RADAR AND SURFACE VISIBILITY OBSERVATIONS. VISIBILITIES
HAVE DROPPED TO AROUND 50 TO 100 FEET BASED ON LAW ENFORCEMENT AND
WEATHER OBSERVER REPORTS ALONG AND SOUTH OF INTERSTATE 94. 

&&

.PREV DISCUSSION... /ISSUED 332 AM CST FRI DEC 25 2009/ 

SHORT TERM...TODAY THROUGH SUNDAY NIGHT...

CHRISTMAS STORM STILL ON TRACK AND EXPECTED TO LINGER THROUGH 
SATURDAY.

CURRENT SATELLITE PICS SHOW THE ELONGATED UPPER LEVEL LOW OVER THE 
WESTERN BORDER OF SOUTH DAKOTA AND NEBRASKA...WITH MOISTURE 
MOVING NORTHWARD EAST OF THIS FEATURE THEN TURNING NORTHWESTWARD AS 
PART OF AN UPPER LEVEL TROUGH OF WARM AIR ALOFT (TROWAL) MAINLY AT 
THE H700 LEVEL...ASSOCIATED WITH THE LIGHT SNOW INTENSIFYING ACROSS 
THE STATE EARLY THIS MORNING. THIS TROWAL FEATURE IS ASSOCIATED WITH 
THE LARGE MAIN SOUTHERN LOW WHICH WAS OVER MISSOURI EARLY THIS 
MORNING. THE LOW IS PROGGED TO MOVE NORTHWARD INTO IOWA BY NOON 
TODAY AS THE NORTHERN UPPER LEVEL LOW MOVES SOUTH AND MERGES WITH 
THE MAIN SOUTHERN LOW BY THIS EVENING. THIS TROWAL IS EXPECTED TO 
REMAIN AN ACTIVE PLAYER OVER NORTH DAKOTA THROUGH SATURDAY AS THE 
MERGED SYSTEM INTENSIFIES AND MOVES TO WISCONSIN BY SATURDAY EVENING 
AND WOBBLES AROUND THE WISCONSIN AREA BEFORE FINALLY PUSHING FARTHER 
EAST INTO THE GREAT LAKES REGION SUNDAY NIGHT.

THIS SCENARIO HAS BEEN QUITE CONSISTENT WITH THE MODELS FOR THE PAST 
COUPLE OF MODEL RUNS AND THE CHANGES THIS FORECAST PACKAGE ARE 
MINOR. NORTHWEST WINDS HAVE INCREASED THIS MORNING ACROSS THE ENTIRE 
REGION...AND SURFACE OBSERVATIONS AND RADAR RETURNS INDICATE SNOW IS 
ON THE INCREASE. WINDS HAVE INCREASED TO 20 TO 25 MPH GUSTING TO 30 
MPH AT TIMES. WINDS ARE EXPECTED TO INCREASE FURTHER TODAY AND 
TONIGHT...THEN BEGIN DECREASING SLOWLY. NORTHWEST WINDS TODAY AND 
TONIGHT SHOULD INCREASE TO 25 TO 35 MPH WITH GUSTS TO 50 MPH AT 
TIMES.

REGARDING SNOWFALL EXPECTED...STILL LOOKING FOR SNOW TOTALS FROM 
TONIGHT THROUGH SATURDAY OF AROUND 2 TO 4 INCHES FROM WILLISTON TO 
BOWBELLS...5 INCHES FROM BEACH TO STANLEY TO KENMARE...10 INCHES 
FROM HETTINGER TO GARRISON TO BOTTINEAU...TO UP TO 15 INCHES FOR 
AREAS SOUTH OF JAMESTOWN.

THE WIND AND SNOW WILL CREATE BLIZZARD CONDITIONS FOR MOST OF THE 
STATE...WITH WHITEOUT CONDITIONS LIKELY. 

HAVE KEPT THE BLIZZARD WARNING HEADLINES GOING TODAY THROUGH 
SATURDAY AFTERNOON FOR ALL OF CENTRAL AND OVER MUCH OF SOUTHWESTERN 
NORTH DAKOTA. A WINTER WEATHER ADVISORY REMAINS IN EFFECT FOR FAR 
NORTHWESTERN NORTH DAKOTA. THAT NORTHWEST CORNER SHOULD GET THE 
LEAST AMOUNT OF NEW SNOW - ONLY 1 TO 4 INCHES - AND THE STRONGEST 
WINDS MAY ONLY REACH 15 TO 30 MPH...LEADING TO REDUCED VISIBILITIES 
BUT NOT WHITEOUT CONDITIONS.

MOTORISTS AND HOLIDAY TRAVELERS ARE URGED TO DELAY TRAVEL UNTIL 
CONDITIONS IMPROVE LATE SATURDAY. STAY INFORMED WITH THE LATEST 
INFORMATION AND FORECASTS AT WEATHER.GOV/BISMARCK.

LONG TERM...MONDAY THROUGH THURSDAY NIGHT...

MODELS BEGIN THE LONG TERM WITH NORTH DAKOTA UNDER A NARROW RIDGE 
EXTENDING NORTHWEST FROM THE GULF COAST TO NORTHERN CANADA. RIDGING 
LASTS UNTIL TUESDAY...AT WHICH POINT BROAD TROUGHING BEGINS TO 
DEVELOP AND COVER MOST OF THE CENTRAL CONUS. RECENT ECMWF SOLUTIONS 
HAVE SHOWN A STRONG CLOSED LOW CLIPPER-TYPE SYSTEM ENTERING THE 
NORTHERN PLAINS MIDWEEK...BUT GFS/NAM SOLUTIONS TREND WITH A MUCH 
WEAKER OPEN WAVE. KEEPING POPS OUT OF THE FORECAST FOR THE LONG TERM 
AS CONFIDENCE REMAINS LOW REGARDING THE TIMING AND STRENGTH OF ANY 
MAJOR WEATHER MAKERS. TEMPERATURES SHOULD BEGIN BELOW NORMAL...WITH 
SLIGHT MODERATION EXPECTED TOWARDS THE END OF THE PERIOD. 

AVIATION...
IFR CONDITIONS WILL CONTINUE AS LOW PRESSURE IN IOWA REMAINS NEARLY 
STATIONARY SPREADING SNOW OVER TAF SITES. 

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
BLIZZARD WARNING UNTIL 6 PM CST /5 PM MST/ SATURDAY FOR 
NDZ003>005-010>013-017>023-025-031>037-040>048-050-051.

WINTER WEATHER ADVISORY UNTIL 6 PM CST SATURDAY FOR NDZ001-002-
009.

&&

$$

SHORT TERM...JV
LONG TERM/AVIATION...BPN/HW
UPDATE...SCHECK