Area Forecast Discussion
Issued by NWS Bismarck, ND

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FXUS63 KBIS 202103

Area Forecast Discussion
National Weather Service Bismarck ND
303 PM CST Mon Nov 20 2017

.SHORT TERM...(This evening through Tuesday)
Issued at 254 PM CST Mon Nov 20 2017

Strong winds this afternoon into tonight, near critical fire
weather conditions south this afternoon, and a much colder
Tuesday highlight the short term forecast.

The strong cold front extending from the clipper across southeast
Manitoba has cleared all of western and central North Dakota as of
21 UTC. Strong post-frontal winds continue to develop across the
area. The strongest winds with gusts of 40-45kts are expected
along and north of North Dakota Highway 200 where isallobaric
forcing will be maximized into the early evening. However, winds
have already peaked across the far northwest, and a slow decrease
in winds are expected through the evening and overnight as
isallobaric forcing focuses into Minnesota. A Wind Advisory
remains in effect until 03 UTC for generally west of US Highway
83, and through 06 UTC to the east. This may be allowed to be
cancelled a bit early.

See the fire weather discussion below regarding a brief period of
near critical fire weather conditions south this afternoon.

A much colder Tuesday is expected area wide as cold high pressure
builds across western and central North Dakota in the wake of the
cold front today. Highs will likely be 20 to 30 degrees colder on
Tuesday for most areas based on the 12 UTC global consensus.

.LONG TERM...(Tuesday night through Monday)
Issued at 221 PM CST Mon Nov 20 2017

A wintry mix Wednesday, possible record highs southwest on
Thanksgiving, and a windy Friday highlight the extended forecast.

The 12 UTC global suite is in agreement on a warm front
propagating into western and south central North Dakota on
Wednesday, and stalling out. A clipper will propagate along this
baroclinic zone and support the potential for a wintry mix of
freezing rain, sleet and snow with an warm layer aloft above sub-
freezing air and road temperatures across northwest and central
North Dakota. Overall QPF amounts are expected to be light,
however, even a small amount of freezing rain will impact
travel on Wednesday. The areas of most concern for light ice
accumulations are across northwest and north central North
Dakota, into the James River Valley.

For Thanksgiving, the baroclinic zone remains, bisecting North
Dakota from northwest to southeast. The 00 UTC NAEFS 850 mb mean
temperatures climb to their 99th percentiles across the west,
supporting the top of the forecast envelope for highs for November
23. The record High for Dickinson is 63 set in 1984, with a
forecast of 65. The record high for Williston is 56, with a
forecast high of 57. With the aforementioned baroclinic zone in
place, a large temperature gradient is favored from southwest to
northeast with highs only in the 20s across the Turtle Mountains.

On Friday, another windy day is possible behind a cold front
extending from a southern Canada clipper system.


.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 254 PM CST Mon Nov 20 2017

Strong northwest winds with gusts of 30 to 45kts will continue
behind a strong cold front this afternoon into tonight. MVFR
stratus may build in behind the front across northern North Dakota
and the James River Valley this evening through tonight.


Issued at 254 PM CST Mon Nov 20 2017

A period of near critical fire weather conditions is ongoing this
afternoon across southern North Dakota where relative humidity
has fallen to near 20 percent with mixing, coincident with strong
post-frontal winds. However, with sunset around 5 pm CST, and
cooler air with higher dewpoints advecting in from the north, the
overall threat should be rather limited in time.


Wind Advisory until 9 PM CST /8 PM MST/ this evening for NDZ001-

Wind Advisory until midnight CST tonight for NDZ003>005-011>013-



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