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fxus63 kbis 231236 
afdbis

Area forecast discussion
National Weather Service Bismarck ND
636 am CST Thu Nov 23 2017

Update...

Issued at 635 am CST Thu Nov 23 2017

Main change with this edit was to increase sky cover west into
central this morning. GOES 16 nighttime imagery indicates broken-overcast
upper level clouds moving east across western into central ND.
Models then take the clouds south after 18z. Possible these clouds
may impact our forecast highs for today. Still think records are
likely given how warm boundary layer temperatures are combined
with a steady westerly mixing wind developing.

High res models continue to bring in some precipitation activity
later this morning-mid afternoon into the west. Global models
remain dry and will continue to side in this direction given
time/height relative humidity cross sections depict cloud bases near 10k feet above ground level.
Something to watch this morning if anything starts to develop over
eastern Montana and starts to reach the ground. No impacts either way
given the warm temperatures expected.



&&

Short term...(today and tonight)
issued at 344 am CST Thu Nov 23 2017

Possible all time record highs for Thanksgiving highlight the short
term forecast.

Currently, there is a northwest-to-southeast boundary across ND
separating cooler air to the northeast and the warmer air to the
southwest. This boundary extended from roughly along and north of
Highway 52. Short term high res models continue to depict good fog
potential, more likely along and north of this boundary. Will keep
the mention of fog going, as the pre-dawn period is usually the
favored time for fog formation.

Strong upper level ridging today should bring even warmer conditions
than yesterday for all of western and central ND. H850 temperatures
of +12c to +14c are forecast...in the 97th to 99th percentiles on
the naefs climatological records. Westerly flow aloft and at the
surface should allow some modest mixing, and provide excellent
conditions for a nice warm-up today.

Record highs are forecast for many locations across western and
central North Dakota.

Location....forecast high...November 23.....Thanksgiving all time

Dickinson........71...........63 in 1984........65 in 1998
Williston........68...........56 in 2011........56 in 2002
Bismarck.........66...........62 in 2011........62 in 2002
Minot............62...........55 in 1942........57 in 2011
Jamestown........58...........59 in 1942........56 in 2011

Long term...(friday through wednesday)
issued at 344 am CST Thu Nov 23 2017

A windy Friday and a potential rain/snow mix Monday highlight the
extended forecast.

A low pressure clipper system over northern Alberta Thursday
afternoon moves southeast into central Manitoba Thursday night and
into western Ontario on Friday. A trailing cold front from this
Canadian clipper is forecast to enter northwestern ND late Thursday
night and sweep southeast across the state Friday morning. 3-hr
pressure rises around 4-6 mb behind the front early in the morning
should allow a period of perhaps 1-3 hours of strong gusty northwest
winds to be realized at the surface. Thereafter, most of the day
will see more modest cold advection and 3-hr pressure rises of 2-4
mb for most of the day Friday. BUFKIT soundings indicate mixing up
to 800-850mb where northwest winds of 40-50 knots could bring wind
gusts into the Wind Advisory category.

Dry and mild for Saturday and Sunday to round out the remainder of
the Holiday weekend. Sunday could see another very mild day over the
southwest half of the state, with highs in the 50s to lower 60s.

The 00z run of the global models depicts the system early next week
as a fairly quick-moving open wave, bringing chances of rain or snow
Monday. Ridging following the wave should keep Tuesday dry. This is
a change from the previous model runs, which depicted a 2-day period
of precipitation. Mainly dry for the rest of next week.

&&

Aviation...(for the 12z tafs through 12z Friday morning)

Issued at 635 am CST Thu Nov 23 2017

Main hazards and impacts to aviation include potential for fog
this morning across the north and east including kisn-kmot-kjms.
For now kept this out of the terminal forecasts as anything has
yet to develop despite models showing widespread fog right now as
of 12z. Think the increasing west-southwest winds and a broken-overcast
cloud deck moving east will prevent anything besides patchy fog to
develop at best through 16z. Otherwise VFR conditions prevail
through the 12z period.



&&

Bis watches/warnings/advisories...
none.
&&

$$

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