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Area forecast discussion 
National Weather Service Bismarck ND
1015 am CST Thursday Nov 26 2015


Issued at 1015 am CST Thursday Nov 26 2015

Upper level trough axis pushing south into northern North Dakota
this morning...then will continue to swing southeast this
afternoon and evening across the state. The upper trough axis will
be accompanied by scattered-broken low clouds and light snow
showers/flurries over the next 12 hours or so. Dryer and less
clouds west near a strong surface high which tracks south-
southeast across eastern Montana today and into western South
Dakota tonight. Main adjustments were made to sky cover today and
tonight...and also bumped temperatures down to slightly below zero across
the west where we are anticipating less cloud cover tonight.

Update issued at 611 am CST Thursday Nov 26 2015

Now that some of the higher clouds have cleared out of the
northwest and portions of the west central it appears there is a
lake effect component to some of the light snow in addition to
the more widespread flurries. Clearing clouds will be a bit
uncertain today with the lake effect maintaining some clouds
central for a while. But as winds become more westerly this
afternoon should see more uniform clearing. Only made some cloud
and temperatures adjustments otherwise current forecast looks


Short term...(today and tonight)
issued at 329 am CST Thursday Nov 26 2015

Sky cover problematic in today's turn affecting
morning temperatures. Now expecting mostly cloudy skies with
flurries most areas today.

Currently...a large cold surface high pressure was over southern
Alberta/Saskatchewan and over Montana...nudging into far western
North Dakota. At upper levels a northern stream trough extend from
north central Canada to near the Montana/ND/sask/man border area. The
southern stream portion of the westerlies was in the form of a
nearly cutoff low over Nevada...with upper level energy impulses
moving northeast from the low across the central/northern plains.

Latest satellite loops...surface observations...and light radar
returns continued to show overcast conditions with low clouds and
scattered flurries over central North Dakota...with some clearing
skies over far western North Dakota. Satellite loops also indicate
middle/high cloud streaming northeastward from Wyoming/South Dakota
into North Dakota. This area is coincident with light radar returns
that encompassed much of South Dakota into southern North Dakota.
Light snow/flurries reported at times over much of North Dakota.

Models indicate that the upper level energy streaming northeastward
from the southern rockies will continue for much of the day
today...finally exiting the southeast part of the state this
evening. Meanwhile the northern stream trough axis enters
northwestern North Dakota this afternoon...and continues moving
southeast across the state tonight. Thus thinking skies will
continue to clear over northwestern North Dakota this morning...then
increasing clouds this afternoon with flurries possible. The
southwest and central should be mostly cloudy today...whether
from low clouds or the middle/high clouds streaming northeastward. Have
kept a mention of flurries through much of the day.

Tonight skies should clear from northwest to southeast as the upper
level northern stream trough axis moves through the state.

Regarding temperatures...went a bit cooler with highs only in the
teens northwest and north central and lower 20s southwest and south
central. A cold night with lows mainly in the single digits above

Long term...(friday through wednesday)
issued at 329 am CST Thursday Nov 26 2015

The extended period features a slow breakdown of the Rex block
across the western US and Canada. As the h500 low over the
southwest US kicks out in response to an eastern Pacific shortwave
trough it will initially retrograde west a bit then head northeast
into the upper Mississippi Valley as a negatively tilted upper
trough. Models by far generate the best precipitation east of the
northern plains but it does appear reasonable for healthy period of
light snow across the west and south...beginning Saturday night
and continuing through Tuesday morning. With very limited Gulf of
Mexico moisture available expect only light amounts of precipitation and
the 2 day snowfall may only amount to 1 to 3 inches during this

Until then...Friday and Saturday will be between the Rex block
components...with the high to the north exerting initial
influence with clear skies and westerly low level (h850) winds.
Highs Friday will be 25 to 30 followed by 30 to 35 Saturday.
Sunday through Tuesday will see highs in the 30s with the above
mentioned chance for light snow across the south. By Wednesday a
better warming trend will take hold as a more substantial h500
ridge builds into the northern plains.


Aviation...(for the 18z tafs through 18z Friday afternoon)

Issued at 1015 am CST Thursday Nov 26 2015

Scattered-broken MVFR ceilings along with isolated flurries persist across
northern and central North Dakota this morning. VFR conditions
west at the moment. Large area of MVFR stratus across south
central Canada pushing south...however how much of this will burn
off remains uncertain. Generally expect partly to mostly cloudy
conditions along with periods of clear this afternoon and evening.
VFR conditions should materialize/prevail later tonight and into
Friday as an upper level trough finally moves out of our area.


Bis watches/warnings/advisories...



Update...New Hampshire
short term...jv
long term...warm air advection
aviation...New Hampshire

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