FXUS63 KBIS 242135
AFDBIS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
335 PM CST THU DEC 24 2009
.SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT...
CHRISTMAS STORM STILL ON TRACK AND EXPECTED TO LINGER THROUGH
SATURDAY.
A LULL IN THE IMPACT OF THIS WINTER STORM SYSTEM TODAY FOR MOST OF
WESTERN AND SOUTH CENTRAL NORTH DAKOTA. MINOT TO JAMESTOWN AND SOUTH
HAVE EXPERIENCED LIGHT SNOW ALL AFTERNOON. CURRENT SATELLITE PICS
SHOW THE ELONGATED UPPER LEVEL LOW OVER THE WESTERN BORDER OF THE
DAKOTAS AND EASTERN MONTANA/WYOMING...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 H850
LEVEL...ASSOCIATED WITH THE LIGHT SNOW THIS AFTERNOON. THIS FEATURE
CONTINUES TO PUSH NORTHWESTWARD/WESTWARD ACROSS NORTHERN AND WESTERN
NORTH DAKOTA TONIGHT AS THE UPPER LEVEL LOW MOVES INTO WESTERN
NEBRASKA BY FRIDAY MORNING AND BEGINS TO MERGE WITH THE MORE
SIGNIFICANT STORM OVER THE SOUTHERN PLAINS. THE MORE SIGNIFICANT
STORM WAS OVER ARKANSAS THIS AFTERNOON AND IS PROGGED TO MOVE
NORTHEASTWARD TO MISSOURI BY DAYBREAK FRIDAY AND MERGE WITH THE
AFOREMENTIONED LOW BY FRIDAY EVENING. THE H700 MID LEVEL TROWAL FROM
THIS SYSTEM BEGINS TO AFFECT THE STATE FRIDAY AFTERNOON THROUGH
SATURDAY WITH HEAVY SNOWFALL EXPECTED. BY FRIDAY EVENING THE
MERGED SYSTEMS WILL RAPIDLY INTENSIFY AND MOVE TO IOWA/ILLINOIS BY
SATURDAY MORNING AND REMAIN NEARLY STATIONARY THROUGH SUNDAY
MORNING.
THIS SCENARIO HAS BEEN CONSISTENT WITH THE MODELS FOR THE PAST
COUPLE OF MODEL RUNS AND THE CHANGES THIS FORECAST PACKAGE ARE
MINOR. WE STILL EXPECT WINDS TO INCREASE TONIGHT ACROSS THE ENTIRE
REGION. SNOW IS EXPECTED TO DEVELOP AND MOVE WEST/NORTHWESTWARD
TONIGHT...MAINLY AFTER MIDNIGHT. BY FRIDAY MORNING...NORTH/NORTHWEST
WINDS OF 20 TO 30 MPH WILL BE FOUND FROM BOWMAN TO BISMARCK TO NEAR
DEVILS LAKE...WITH 15 TO 25 MPH WINDS NORTH AND WEST OF THAT LINE.
WINDS WILL INCREASE TO 30 TO 40 MPH OVER CENTRAL AND SOUTHWESTERN
NORTH DAKOTA BY NOON FRIDAY...WITH 20 TO 30 MPH WINDS IN THE
NORTHWEST CORNER. MAY SEE GUSTS TO 45 OR 50 MPH IN THE CENTRAL AND
SOUTHEAST DURING THE AFTERNOON AND INTO FRIDAY NIGHT. GUSTY
NORTHWEST WINDS TO CONTINUE INTO SATURDAY...BUT NOT AT THE STRENGTH
OF FRIDAY'S WINDS. SATURDAY'S WINDS CLOSER TO 20 TO 30 MPH.
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 UPGRADED MOST OF THE BLIZZARD WATCH IN THE WESTERN QUARTER OF
THE STATE THAT WAS TO HAVE TAKEN EFFECT FRIDAY MORNING TO A BLIZZARD
WARNING...WITH A WINTER WEATHER ADVISORY CONTINUING FOR THE FAR
NORTHWEST COUNTIES FOR SNOW AND BLOWING SNOW. 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.
WILL CONTINUE WITH THE WINTER STORM WARNING FOR CENTRAL NORTH DAKOTA
THROUGH TONIGHT...AND KEEP THE BLIZZARD WARNING BEGINNING 12Z FRIDAY
THROUGH SATURDAY.
MOTORISTS AND HOLIDAY TRAVELERS ARE URGED TO STAY INFORMED WITH THE
LATEST INFORMATION AND FORECASTS AT WEATHER.GOV/BISMARCK.
.LONG TERM...MONDAY THROUGH THURSDAY..
THE ECMWF AND GFS MODELS CONTINUE TO BE IN FAIR AGREEMENT ON MONDAY
WITH A BROAD UPPER LEVEL RIDGE OVER THE ROCKIES AND A ELONGATED
UPPER LEVEL LOW/TROUGH OVER EASTERN CANADA AND THE EASTERN US.
ALTHOUGH BOTH THE GFS AND ECMWF INDICATE THIS PATTERN IS
TRANSITORY...THEY HAVE DIVERGENT SOLUTIONS. EVEN SO...BOTH MODELS
TEND TO KEEP ANY SIGNIFICANT WEATHER SYSTEMS OUT OF THE FORECAST
AREA WHICH IS IN LINE WITH THE PREVIOUS FORECAST. SO EXCEPT FOR
MODIFYING TEMPERATURES WILL KEEP POPS LOW AND NOT MENTION PRECIP.
&&
.AVIATION...
A SURFACE LOW IN IOWA IS FORECAST TO DEEPEN OVERNIGHT AND SPREAD
MODERATE TO HEAVY SNOWFALL WITH STRENGTHENING SURFACE WINDS
ESPECIALLY ACROSS KMOT...KBIS...AND KJMS. THE HEAVY SNOW AND AND
INCREASING WINDS WILL ALSO COMBINE TO LOWER VISIBILITIES TO LIFR AT
THE PREVIOUSLY MENTIONED TAF SITES. KDIK AND KISN TAF SITES WILL SEE
INCREASING WINDS AS WELL AND SNOW BUT CONDITIONS WILL BE MAINLY MVFR
TO IFR.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 6 AM CST /5 AM MST/ FRIDAY FOR
NDZ003>005-011>013-019>023-025-034>037-042-045>048-050-051.
BLIZZARD WARNING FROM 6 AM CST /5 AM MST/ FRIDAY TO 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/ FRIDAY FOR
NDZ010-017-018-031>033-040-041-043-044.
WINTER WEATHER ADVISORY UNTIL 6 PM CST SATURDAY FOR NDZ001-002-
009.
&&
$$
SHORT TERM...VINING
LONG TERM/AVIATION...WALKER/COUSINS
