FXUS63 KBIS 050929
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
329 AM CST SUN FEB 5 2012

.SHORT TERM...TODAY THROUGH MONDAY...

THE CHALLENGE FOR THE MORNING IS ONCE AGAIN PREDICTING THE
DISSIPATION OF FOG AND LOW STRATUS CONFINED MOSTLY TO AREAS ALONG
AND NORTH AND EAST OF THE MISSOURI RIVER. THE DETERMINISTIC
MODELS ARE HAVING A VERY DIFFICULT TIMING RESOLVING THE
STRATUS...WITH THE 06 UTC HRRR THE ONLY MODEL WITH A HANDLE ON THE
EVENT...SUGGESTING DISSIPATION OF THE FOG AND STRATUS BY EARLY
AFTERNOON AT THE LATEST AS MIXING INCREASING AHEAD OF A SURFACE
TROUGH. HAVE TRENDED SLIGHTLY FASTER THAN THE
HRRR...HOWEVER...MUCH UNCERTAINTY AS TO WHEN THE STRATUS WILL
COMPLETELY DISSIPATE DOES REMAIN. HAVE REMOVED MORTON AND SIOUX
COUNTIES FROM THE DENSE FOG ADVISORY...AND WILL LEAVE THE
REMAINING COUNTIES IN PLACE THROUGH 15 UTC. TWO OTHER PATCHES OF
DENSE FOG ARE BEING OBSERVED AS OF 09 UTC...INCLUDING THE
WILLISTON THROUGH TIOGA AREAS AND RUGBY THROUGH BOTTINEAU. DUE TO
THE VERY LOCALIZED NATURE OF THESE AREAS...WILL COVER WITH AN SPS.

A VERY MILD EARLY FEBRUARY DAY IS FORECAST ACROSS WESTERN AND
CENTRAL NORTH DAKOTA TODAY DUE IN LARGE PART TO THE ABSENCE OF SNOW
COVER ACROSS THE AREA. THE ABUNDANCE OF BROWN GROUND WILL YIELD
GREATER MIXING HEIGHTS ENABLING THE RELATIVELY MILD TEMPERATURES IN
THE 850-800 MB LAYER OF +4 TO +6 C TO BE MIXED TO THE
SURFACE...RESULTING IN WIDESPREAD 50S FOR HIGH TEMPERATURES FOR MOST
AREAS...ESPECIALLY ALONG AND SOUTH OF THE MISSOURI RIVER...WITH
UPPER 40S FOR HIGHS FOR THE JAMES RIVER VALLEY...TURTLE MOUNTAINS
AND LOCATIONS ALONG THE INTERNATIONAL BORDER. TRENDED WELL ABOVE
THE DETERMINISTIC AND STATISTICAL CONSENSUS AND OPTED FOR THE SUPERIOR
VERIFICATION OF BIAS CORRECTED GUIDANCE GIVEN THE BROWN WINTER WE
ARE HAVING. SHOWN BELOW ARE THE FORECAST HIGHS AND RECORD HIGHS
FOR TODAY FOR THE MAJOR OBSERVING LOCATIONS. SEE THE FIRE WEATHER
DISCUSSION BELOW REGARDING FIRE DANGER FOR TODAY.

LOCATION........FORECAST...........RECORD

BISMARCK..........53...............56 1991
JAMESTOWN.........49...............58 1991
MINOT.............54...............58 1963
WILLISTON.........51...............55 1963
DICKINSON.........54...............58 1963

A SURFACE COLD FRONT IS FORECAST TO CROSS THE INTERNATIONAL BORDER
AROUND 00 UTC THIS EVENING AND PROPAGATE SOUTH THROUGH THE
NIGHT...ENTERING SOUTH DAKOTA BETWEEN 08 AND 10 UTC. GIVEN POST
FRONTAL MIXING AND WARM TEMPERATURES TO BEGIN THE OVERNIGHT...LOW
TEMPERATURES SUNDAY NIGHT SHOULD ONLY FALL INTO THE LOW 20S FOR MOST
LOCATIONS...WITH TEENS ALONG THE INTERNATIONAL BORDER. A BREEZY
MONDAY IS EXPECTED IN THE WAKE OF THE COLD FRONT AS 1045 MB SURFACE
HIGH BEGINS TO BUILD INTO THE STATE. AIDED BY AN AN ISALLOBARIC
COMPONENT FROM PRESSURE RISES AND LOW LEVEL COLD AIR ADVECTION
PROMOTING MIXING TO AROUND 825 MB...NORTHERLY WIND GUSTS TO 25 KTS
ARE EXPECTED FOR MOST AREAS WITH FLURRIES ASSOCIATED WITH STRATUS
APPROXIMATELY ALONG AND NORTH OF A LINE FROM CROSBY THROUGH
WASHBURN THROUGH EDGELEY. DESPITE THE COLD FRONTAL
PASSAGE...TEMPERATURES ON MONDAY WILL STILL BE ABOVE NORMAL THANKS
TO NO SNOWPACK WITH HIGHS FROM THE LOW TO MID 20S NORTH TO THE
LOWER 30S SOUTH.

.LONG TERM...MONDAY NIGHT THROUGH SATURDAY...


MODELS IN FAIR AGREEMENT WITH FEATURES IN LONG TERM. USED THE BLEND
WITH FEW CHANGES. LARGE MID AND UPPER LEVEL RIDGE LIES ALONG SPINE
OF THE ROCKIES WITH FAIRLY STRONG HIGH PRESSURE DROPPING SOUTH IN
LEE OF CANADIAN ROCKIES. 1044 HIGH WOULD INDICATE A VERY CHILLY
MIDDLE OF THE WEEK...HOWEVER WITH NO SIGNIFICANT SNOW COVER UPSTREAM
FROM THE THE CENTRAL ALBERTA AND SASKATCHEWAN BORDER...SOUTH THROUGH
THE NORTHERN PLAINS...TEMPERATURES WILL BE NORMAL OR SEVERAL DEGREES
ABOVE NORMAL.

ONLY ONE CHANCE OF ACCUMULATING PRECIPITATION WHICH WILL COME
WEDNESDAY NIGHT AS A REINFORCING SHOT OF MODIFIED ARCTIC AIR MOVES
SOUTH BEHIND A COLD FRONT. THE SYSTEM LOOKS QUITE DRY AND THE
HIGHEST POPS...SLIGHT CHANCE...ARE IN THAT PERIOD. WHILE AIR WILL BE
COLDER...THICKNESS AND 85H TEMPERATURES INDICATE THAT THE COLDEST
AIR WILL PASS JUST TO THE EAST OF THE FORECAST AREA BORDER.


&&

.AVIATION...

BAND OF STRATUS EXTENDS ABOUT 50 MILES EITHER SIDE OF MISSOURI
VALLEY FROM THE SOUTH DAKOTA BORDER NORTH TO NEAR LAKE
SAKAKAWEA...THEN NORTHEAST TO WILLISTON. SEVERAL OTHER MUCH SMALLER
BANDS LINGERED OVER EASTERN PORTIONS OF THE FORECAST AREA...KJMS AND
EAST AND KRUG AND EAST. THE AREAS SHOWED LITTLE MOVEMENT...BUT WERE
SLOWLY SHRINKING IN AREAL COVERAGE. HOWEVER THE MISSOURI VALLEY
ESPECIALLY FROM KBIS TO KISN WILL LINGER IN LIFR CONDITIONS FOR
SEVERAL MORE HOURS BEFORE A TRANSITION OF VFR BY THE AFTERNOON ALL
AERODROME SITES.


&&

.FIRE WEATHER...

SUNDAY LOOKS TO BE VERY MILD ACROSS WESTERN AND CENTRAL NORTH
DAKOTA WITH HIGHS IN 50S. WITH PLENTIFUL DRY VEGETATION IN
PLACE...AND AFTERNOON RELATIVE HUMIDITY VALUES EXPECTED TO FALL
INTO THE 25 TO 35 PERCENT RANGE ESPECIALLY ALONG AND SOUTH OF THE
MISSOURI RIVER...THE ONE THING PREVENTING FIRE WEATHER CONCERNS
ARE WIND SPEEDS ONLY ON THE ORDER OF 10 TO 15 MPH.


&&

.BIS WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR NDZ035>037-
046-047-050.

&&

$$

SHORT TERM/FIRE...PJA
LONG TERM/AVIATION....HW



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