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Area forecast discussion 
National Weather Service Bismarck ND
103 am CST Sat Nov 28 2015


Issued at 103 am CST Sat Nov 28 2015

Middle/upper level col developing across the northern plains. Clear
skies across western and central North Dakota with breezy winds
north. Winds will slowly wind down now through 12z as gradient
forcing decreases.

A clear sky continues into Saturday before increasing clouds
across the south Saturday evening.

Update issued at 931 PM CST Friday Nov 27 2015

Again no major changes required. Just minor tweaks to temperatures
and winds to match latest trends.

Update issued at 624 PM CST Friday Nov 27 2015

No changes required for this update.


Short term...(this evening through saturday)
issued at 230 PM CST Friday Nov 27 2015

Dry...quiet and somewhat warmer weather is expected tonight and

Tonight...southwesterly return flow in the lower to middle parts
of the atmosphere has been aiding warm air advection during the
day as a surface ridge axis slides southeast of the area. It was
the proximity of that ridge axis that helped enable the cold low
temperatures Friday lows tonight will be warmer. We
did...however...weight the official forecast slightly toward the
cooler numbers provided by recent bias-corrected MOS guidance to
advertise another round of lows in the single digits f for parts
of the area...coldest in typically cool spots like Hettinger.

Saturday...we leaned a bit toward the warmer edge of guidance in
respect to the diurnal temperature rises observed Friday...which
were greater than short-range guidance expected for all but the
Williston Basin. That/S likely due to the snow-free ground across
much of the area. Thus...forecast highs are deep into the 30s f
for most of the area on Saturday. Cloud cover will increase over
the south by late in the day as a shortwave trough approaches...
but we kept the daytime forecast dry everywhere because the lower
atmosphere will be quite dry.

Long term...(saturday night through friday)
issued at 230 PM CST Friday Nov 27 2015

Focus in the long term is on the potential for snow Sunday into
Tuesday morning.

The 12 UTC model guidance continues to show the Rex block over the
western Continental U.S. Dissipating and the upper level low propagating into
The Rockies Sunday then into the Central Plains Monday. This pattern
allows for two different waves of precipitation to move into the

Chances for snow from the initial wave will come early Sunday with
the upper level low still over The Rockies. At this time
accumulations from this wave should remain light with chances for
snow mainly in the southwest.

The second chance for snow will come Monday morning and persist into
Tuesday morning as the closed upper level low tracks across the
Central Plains into the Great Lakes region. At this time the
southern tier counties of central North Dakota have the best chance
for accumulating snow. While uncertainty is still high with the
track of this system...snow accumulations Sunday into Tuesday
morning could be in the 3 inch range for these counties.


Aviation...(for the 06z tafs through 06z Saturday night)

Issued at 103 am CST Sat Nov 28 2015

VFR with light winds and clear skies at all taf sites through the
taf period. Models are hinting at patchy sub-IFR ceilings and vcfg
late Saturday night developing after 06z.


Bis watches/warnings/advisories...



Update...New Hampshire
short term...cjs
aviation...New Hampshire

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