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Area forecast discussion 
National Weather Service Bismarck ND
333 am CDT Sat Aug 1 2015

Short term...(today and tonight)
issued at 301 am CDT Sat Aug 1 2015

A very warm day today highlights the short term forecast.

Northwest upper level jet flow continued over the state...with
an upper level low over Hudson Bay and a warm western ridge over the
West Coast and rockies. Warm and dry air was southwest of the upper
level jet with cooler air to the northeast.

Early this morning isolated showers developed...likely along a
boundary between a southerly low level jet along western Nebraska
into the western Dakotas. Enough lift was occurring in a northwest-
to-southeast fashion across central North Dakota. The latest
iteration of the hrrr indicates the area of isolated showers
shifting east to the James Valley before sunrise...then continuing
east out of the James Valley.

A cold front over the central Canadian prairie provinces this
morning is forecast to move south today and enter northwestern North
Dakota by this evening...sweeping southeast across the state
tonight. Look for a very warm day today ahead of the front. Westerly
mixing winds aloft should increase with the approach of the front
due to the increasing pressure gradient. Forecast soundings indicate
an adiabatic link from the surface up to around h700 this afternoon.
Went above guidance for maximum temperatures and raised winds a bit as well
from guidance. Looking at highs today in the low to middle 90s over
most of western and central North Dakota.

Tonight as the cold front sweeps southeast across the state...the
best upper level forcing resides to our northeast in the flow of the
upper jet - which should have lifted northeast during the day
allowing the very warm and dry air to advance into central North
Dakota. Have kept the slight chances of thunderstorms across The
Turtle mountain area. Cooler air moves into the state tonight with
northwest winds behind the cold front. Kept lows tonight in the 50s
as the northwest winds will keep the lower atmosphere mixed enough
so that temperatures do not drop into the 40s.

Long term...(sunday through friday)
issued at 301 am CDT Sat Aug 1 2015

Cooler temperatures expected over the area on Sunday in the wake
of the cold front. Otherwise...dry conditions expected with upper
ridge axis sliding over The Rockies and surface high settling over
the region. Dry weather continues into Monday with ridge axis
pushing towards the northern plains.

Active weather pattern expected towards middle-week with ridge
breaking down and a variety of short waves ejecting over the area
from a broad upper low over British Columbia. Unsettled pattern
continues into the end of the week as low starts to make its way
easterly. Below average temperatures expected through the period.


Aviation...(for the 06z tafs through 06z Saturday night)
issued at 1223 am CDT Sat Aug 1 2015

VFR conditions will continue through the forecast period. Surface
flow will remain light and variable for the nighttime hours. On
Saturday winds should become southerly or southwesterly ahead of
a cold front that is forecast to move through kisn around 00z...and
through kmot and kdik around 04z Saturday evening. Southwest winds
could be gusty at times at kisn and kdik in the afternoon between
17z and 00z.


Fire weather...
issued at 301 am CDT Sat Aug 1 2015

An adiabatic lapse rate up to h700 this afternoon will allow
mixing winds aloft to link with the surface. Expecting 15 to 20
miles per hour winds for a time this afternoon in the west as temperatures
reach into the 90s. Dewpoints in the 40s over southwestern North
Dakota this morning are expected to drop into the 30s this
afternoon as the lower atmosphere mixes with middle levels.
Temperatures in the middle 90s with dewpoints in the 30s should
result in minimum relative humidity values in the 10 to 15 percent
range over much of western North Dakota...mainly along and west of
a line from Williston to Watford City to Dickinson and Hettinger.
In addition...winds aloft should also mix down to the surface for
a time this afternoon...with westerly winds of 15 to 20 miles per hour

Expect that Grasslands in the southwest are curing quickly.
The latest assessment from land managers indicated that slope and
Bowman counties would likely be the first to reach critical fuel
moisture levels at some point. Weather conditions expected today
would warrant a red flag mention for Williston to Hettinger and
westward...but understand that Grasslands have not yet reached
critical fuel moisture levels.

Cooler conditions with higher relative humidity values are expected
on Sunday...after a cold frontal passage Saturday night.


Bis watches/warnings/advisories...


Short term...jv
long term...jjs
fire weather...jv

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