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Area forecast discussion 
National Weather Service Cheyenne Wyoming
1050 am MST sun Feb 7 2016

issued at 928 am MST sun Feb 7 2016

Updated forecast for the timing of the weak band of snow entering
far eastern Wyoming this morning. This band has produced
visibilities around 1 mile across the Panhandle of
do not expect any significant impacts as it slowly moves southeast
and weakens.

For winds MOS guidance is a whole 10 knots lower
compared to yesterday at this time. This is probably because of
the significant cloud cover over the Panhandle this morning. Will
keep the High Wind Warning going for now since Rapid City is
currently experiencing gusts over 60 miles per hour and skies have clear
across Dawes and northern Sioux counties...but if winds do not
increase dramatically in the next few hours may need to downgrade
to an advisory.


Short term...(today and tonight)
issued at 153 am MST sun Feb 7 2016

Today...fortunately...wind speeds slowly decreasing across our
southern Laramie range as gradients relax somewhat and thus will
likely be able to cancel the High Wind Warning there.

Flow aloft veers to north northwest with strong winds aloft this
afternoon across far eastern Wyoming and western Nebraska...100
knots at 500 mb...and 60 to 70 knots at 700 mb. Some downward
vertical motion noted and hopefully this will be enough...along with
deep unidirectional aid in stronger winds mixing down to
the surface...thus the inherited High Wind Warning for western
Nebraska looks good.

Compromised for high temperatures between the NAM and GFS MOS
maximums as we will see cold air advection today...making for tricky
high temperature forecasts.

Tonight...although fast north northwest flow aloft
continues...expect surface winds to decrease as the low levels of
the atmosphere decouple. Dry with limited low and middle level moisture
and lack of lift.

Monday...warming trend begins as heights and thicknesses start to
rise...although high temperatures will be limited by northwest flow
aloft and at least scattered middle and high clouds.

Monday night...moderating airmass continues...thus not quite as cold
as Sunday night. Still dry with lack of low and middle level moisture
and lift.

Long term...(monday through saturday)
issued at 153 am MST sun Feb 7 2016

A high amplitude ridge will keep hold over the western Continental U.S.
Through Tuesday...and will flatten a bit on Wednesday as a
shortwave feature rounds the top of the ridge. Winds in this
pattern will remain on the breezy side...with a slight increase
expected Wednesday and Wednesday night as the shortwave rounds
the ridge and deepens the leeside pressure trough. However...winds
in the 800-700mb layer are prognosticated to only increase to 35 to 45
kts so high winds look unlikely at this time. Temperatures will be above
average for this time of year with 40s/50s east and 30s/40s west.
The ridge will rebuild over the West Coast on Thursday and will
begin to shift east over The Rockies Friday and Saturday as a
stronger shortwave trough moves onshore. As this occurs...expect
winds across the forecast area to diminish somewhat for Friday and
Saturday as the surface pressure gradient weakens. Dry conditions
will prevail through the week...with the next chance for precipitation
late in the weekend as the shortwave trough approaches from the


Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1045 am MST sun Feb 7 2016

It will be quite windy through this afternoon for areas to the
east of the Laramie range. Good mixing and strong winds aloft will
cause northwest winds to gust to 35-45 kts. The winds will
decrease some after sunset but still remain breezy through much of
the night. A scattered-to-bkn layer of clouds with bases 5-10 thousand
feet will be possible for locations near the Colorado border
through the early afternoon.


Fire weather...
issued at 153 am MST sun Feb 7 2016

Minimal concerns due to relatively high humidities
the next several days and snow cover.


Cys watches/warnings/advisories...
NE...High Wind Warning until 6 PM MST this evening for nez002-003-



short term...Rubin
long term...rjm
fire weather...Rubin

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