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Area forecast discussion 
National Weather Service Cheyenne Wyoming
1041 PM MDT Friday Oct 31 2014

issued at 704 PM MDT Friday Oct 31 2014

Winds are still gusty out in the Panhandle this evening...but are
showing signs of slowly coming down. Only site now hitting
advisory level is the Kings Canyon RAWS site. Summer Crest has
seen a slow decrease as well as Alliance and Chadron. Went ahead
and let the Wind Advisory expire on time at 7 PM. Updates have
been sent.


Short term...(this evening through Sunday night)
issued at 330 PM MDT Friday Oct 31 2014

Pretty quiet weather pattern through midday Sunday. Main concern
this evening will be the gusty south winds across the Nebraska
Panhandle. Still getting a few gusts to 35-40 miles per hour this afternoon
over the northern Panhandle...mainly over the Pine Ridge. Will
continue the Wind Advisory through 01z. It will still be breezy
through the night especially over the elevated Pine Ridge as both
the GFS and NAM indicate a low level jet developing around 850mb at cdr.
Pressure falls occur over Wyoming on Sat in advance of large scale
trough across the western United States. With good warm advection
taking place...highs will be a 10-15 degrees warmer than today. It
will not be nearly as windy over the Nebraska Panhandle as the
gradient relaxes.

Upper trough to the west of the County Warning Area begins to shear out on Sat
night with one piece of energy lifting northeastward into Idaho
and the other pushing into southern Nevada. With a surface low across
northeast Wyoming on Sat night...southwest winds will increase to the
west of the Laramie range. May have the potential for some higher
wind gusts (45-55 mph) in the Arlington area by sunrise Sunday as
the models show 700mb southwest winds of around 40 kts. One more
mild day on Sunday in advance of cold front that is prognosticated to
push across the County Warning Area on Sun night. The European model (ecmwf) shows much better
precipitation chances in areas along the Colorado border for late Sun
night into Monday morning compared to the drier GFS...although it
appears the best forcing is still over northern Colorado. Will show
chance probability of precipitation for now. Post frontal temperatures would be cold enough to
support snow over much of the area.

Long term...(monday through friday)
issued at 330 PM MDT Friday Oct 31 2014

Broad upper trough shifts gradually eastward across eastern
Wyoming and western Nebraska on Monday with a drier northwest flow
aloft pushing in during the afternoon. Most of the snow and rain
showers should push east of our area by late in the day...with a
brief but colder airmass moving in. Temperatures on Monday will be
some 20 degrees colder in comparison to the previous days. The
upper trough shifts east of the area on Tuesday with a dry
northwesterly middle to upper level flow becoming more westerly
across the region through late in the week as a high pressure
ridge builds in across California. Temperatures at or slightly
below seasonal values will gradually warm a bit by midweek as the
low level flow GOES more westerly and downslope. Tuesday afternoon
and evening looks to be our windiest period in the extended
range...particularly in our usual problem areas like
Bordeaux...Arlington and Elk Mountain when the pressure gradient
between a low level high pressure system over western Colorado and
a low over the Dakotas tightens up. Right now looking like winds
could gust up to around 45 miles per hour in the usual windier areas late
Tuesday. Otherwise...forecast remains dry and otherwise uneventful
Tuesday through Friday.


Aviation...(for the 06z tafs through 06z Saturday night)
issued at 1038 PM MDT Friday Oct 31 2014

VFR conditions expected through the next 24-36 hours as gusty west
to southwest winds continue. Do begin to see a change in the
weather Sunday as low pressure begins to move in from the west.
Could see widespread snow across southern Wyoming and northern
Colorado with decreasing flight conditions Sunday night into
Monday. More on that as the event draws closer.


Fire weather...
issued at 330 PM MDT Friday Oct 31 2014

No fire weather concerns through early next week. Mild
temperatures are expected on Saturday and Sunday with minimum
afternoon humidity values in the 25-35 percent range. Southwest
winds will increase across southeast Wyoming on Sunday in advance
of a cold front. Much cooler temperatures will push across the
area on Sunday night and Monday behind a cold front with light
precipitation possible in areas near the Colorado border.


Cys watches/warnings/advisories...


short term...zf
long term...jg
fire weather...zf

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