FXUS63 KBIS 250932
AFDBIS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
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...
WINTER STORM WARNING UNTIL 6 AM CST /5 AM MST/ EARLY THIS
MORNING FOR NDZ003>005-011>013-019>023-025-034>037-042-045>048-
050-051.
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 AM CST /5 AM MST/ EARLY THIS
MORNING FOR NDZ010-017-018-031>033-040-041-043-044.
WINTER WEATHER ADVISORY UNTIL 6 PM CST SATURDAY FOR NDZ001-002-
009.
&&
$$
JV/BPN/HW
