Area Forecast Discussion
Issued by NWS Bismarck, ND

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS63 KBIS 221243
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
643 AM CST Wed Nov 22 2017

.UPDATE...

Issued at 642 AM CST Wed Nov 22 2017

Only changes to the forecast were to adjust hourly weather
elements based on latest obs. Otherwise we remain on track.


&&

.SHORT TERM...(Today and tonight)
Issued at 346 AM CST Wed Nov 22 2017

A chance of light snow with less of a chance of a wintry mix far
northwest and north central this morning, and breezy conditions this
afternoon with strong warm advection highlights the short term
forecast.

Currently, the arctic high pressure ridge axis was off to our east
over the Red River Valley, then extending northwest into northern
Saskatchewan. Meanwhile, a low pressure clipper was over southern
Alberta, with it`s warm front extending from the low across central
Montana into eastern Wyoming. Southerly winds ahead of the warm
front were already increasing to around 10 mph over western ND, with
rising temperatures reaching into the low/mid 20s in the southwest.

The clipper should track along the MT/Saskatchewan border early this
morning, then take a southeasterly track across western and central
ND this afternoon, reaching the southeast corner of ND by evening.

The surface warm front should move into western ND after sunrise and
move east across the state today. The surface warm front will be
lead by an elevated warm layer aloft ahead of the surface front with
a northwest-to-southeast oriented leading edge. Since this track is
farther north than yesterday`s model runs suggested, the potential
for a wintry mix of freezing rain, sleet and snow has also
diminished, with the anticipated precip falling mainly in the cold
sector or along the leading edge of the warm layer aloft. We are now
expecting mainly light snow, with the slight possibility of sleet on
the western edge of the area of precipitation as it tracks east
across northern ND into the northern James Valley this morning.
Although the threat for freezing precip has diminished, even
even a small amount of sleet or freezing rain will impact travel.

The aforementioned track of the clipper will lead to a large spread
in forecast highs for today from northeast to southwest: Temps
reaching only into the 20s across the Turtle Mountains, to the 50s
and lower 60s mainly along and south/west of the Missouri River.
Brisk northwest winds with gusts around 30s kts are forecast across
southwest North Dakota in the wake of the clipper.

.LONG TERM...(Thursday through Tuesday)
Issued at 346 AM CST Wed Nov 22 2017

Record highs possible on Thanksgiving, and a very windy
Friday highlight the extended forecast.

The 00 UTC NAEFS 850 mb mean temperatures continue to depict 99th
percentiles across much of western North Dakota on Thanksgiving
(yesterday`s day shift mentioned this fact). Kept the forecast high
temps for Thursday from the previous forecast, as this was higher
than a model blend and temps should be on the higher end of the
guidance. Western and much of central ND should see surface
southwest winds of 10 to 15 mph, providing good mixing from the
surface to h850, and the warming should be realized over western and
much of central ND, but Bottineau, the Turtle Mountains and James
Valley may not see such strong warming, with lighter south/southwest
winds expected there. Therefore a large temp gradient should be seen
once again from northeast to southwest.

Highs around 70 are forecast southwest, with perhaps only the 40s
and lower 50s for the James River Valley and Turtle Mountains.

Location....Forecast High...November 23.....Thanksgiving All Time

Dickinson........70...........63 in 1984........65 in 1998
Williston........64...........56 in 2011........56 in 2002
Bismarck.........60...........62 in 2011........62 in 2002
Minot............57...........55 in 1942........57 in 2011

Not expecting near record highs for the James Valley:

Jamestown........46...........59 in 1942........56 in 2011

Friday still looking very windy in the wake of a strong cold front
extending from a clipper system moving across Manitoba into Ontario.
Strong gradient winds with 45-55 kts to mix in the 800-850mb layer,
with steep low level lapse rates and cold air advection behind the
front support the potential for strong winds across western and
central North Dakota on Friday. A wind advisory may be needed.

Upper level ridging following the Friday clipper will bring quiet
weather for Saturday and Sunday to bring an end to the holiday
weekend.

An upper level longwave trough is progged to move east across the
Rockies on Monday and across the western plains states on Tuesday.
This will bring the next chances of rain and snow to our region for
early next week.

&&

.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)

Issued at 642 AM CST Wed Nov 22 2017

Early today (13-17z)low level wind shear develops over western ND
with 40-50kt winds around 2000 feet and light south to southwest
winds at the surface. VFR clouds and light precipitation will
spread quickly across KISN and KMOT, moving east by 16-17Z.
Surface winds shift from south to west to northwest at all taf
sites during the day with the passage of a surface front.


&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...NH
SHORT TERM...JV
LONG TERM...JV
AVIATION...NH



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.