FXUS63 KBIS 232306
AFDBIS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
506 PM CST WED DEC 23 2009
.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT
MODELS IN GOOD AGREEMENT ON MERGER OF NORTHERN AND SOUTHERN STREAM
UPPER LOWS...AND PROLONGED SIGNIFICANT WEATHER EVENT ACROSS THE
FORECAST AREA THROUGH SATURDAY. HAVE INCREASED POPS INTO SATURDAY
AND SATURDAY EVENING...WITH TROWAL FEATURE LIKELY KEEPING AT LEAST
MODERATE SNOWS GOING...ALONG WITH CONTINUED WIND IMPACT. EXPECT
LIGHT TO MODERATE SNOW AND WINDS MAINLY 15 TO 25 MPH TONIGHT
THROUGH THURSDAY. MORE SEVERE CONDITIONS ARE EXPECTED LATE
THURSDAY NIGHT...THROUGH CHRISTMAS DAY INTO SATURDAY. LOOK FOR
HEAVIER SNOW...AND VERY STRONG NORTHWEST WINDS...ESPECIALLY ACROSS
THE SOUTHEAST HALF OF THE FORECAST AREA. SUSTAINED SPEEDS OF 25 TO
35 MPH ARE EXPECTED OVER THESE AREAS...WITH GUSTS OF 40 TO 50 MPH.
A BLIZZARD WATCH REMAINS IN EFFECT FOR FRIDAY INTO SATURDAY...AND
WILL LIKELY BE UPGRADED OVER THE FAVORED LOCATIONS OVERNIGHT.
TRAVEL WILL BECOME EXTREMELY DANGEROUS...IF NOT IMPOSSIBLE...LATE
THURSDAY NIGHT INTO SATURDAY. REFER TO WEATHER.GOV/BISMARCK FOR
MORE DETAILS OF SNOWFALL TOTALS THROUGH SATURDAY. HIGHEST AMOUNTS
OF 12 TO 16 INCHES...AND LOCALLY HIGHER...ARE EXPECTED EAST OF A LINE
FROM ROLETTE...TO BUTTE AND WASHBURN...SOUTH THROUGH BISMARCK TO
SELFRIDGE. LESSER AMOUNTS OF 8 TO 12 ARE EXPECTED FROM
MINOT...SOUTH THROUGH GARRISON AND MANDAN...TO ELGIN. 4 TO 8 INCH
TOTALS WILL BE COMMON THROUGH SATURDAY OVER THE WESTERN COUNTIES.
.LONG TERM...SUNDAY THROUGH WEDNESDAY
THE MODELS ALL ARE IN AGREEMENT INITIALLY AND INDICATE A COMBINATION
OF SURFACE HIGH PRESSURE AND AN UPPER LEVEL RIDGE COVERING THE HIGH
PLAINS EAST OF THE ROCKIES. THIS SHOULD KEEP THE CHANCE OF
SIGNIFICANT PRECIPITATION LOW. BY WEDNESDAY THE MODELS DIVERGE SO
FOR NOW WILL STAY WITH THE TREND OF THE PREVIOUS FORECAST WHICH
KEEPS POPS LOW AND FOLLOWS THE GFS TREND. OVERALL TEMPS WILL BE
BELOW NORMAL THROUGH THE PERIOD.
&&
.AVIATION...
EXPECT CENTRAL ND TO CONTINUE TO HAVE INTERMITTENT LIGHT
SNOW AND VARIABLE LOW CEILINGS THROUGH THURSDAY AFTERNOON AS A LARGE
LOW PRESSURE SYSTEM DOMINATES THE WEATHER IN THE CENTRAL US. THIS
WILL CAUSE WIDESPREAD IFR CONDITIONS DUE TO LOW CEILINGS AND
VISIBILITIES IN SNOW. THE FAR WEST WILL BE ON THE FRINGE OF THE
SYSTEM AND COULD SEE IMPROVEMENT AFTER MIDNIGHT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 6 AM CST /5 AM MST/ FRIDAY FOR
NDZ003>005-011>013-019>022-034-035-042-045-046.
BLIZZARD WATCH FROM FRIDAY MORNING THROUGH SATURDAY AFTERNOON
FOR NDZ001>005-009>013-017>023-025-031>037-040>048-050-051.
WINTER WEATHER ADVISORY UNTIL 6 AM CST /5 AM MST/ FRIDAY FOR
NDZ001-002-009-010-017-018-031>033-040-041-043-044.
WINTER STORM WARNING UNTIL 6 AM CST FRIDAY FOR NDZ023-025-036-
037-047-048-050-051.
&&
$$
TSW/RK
