Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Cheyenne Wyoming
435 PM MST Tuesday Mar 3 2015
Short term...(this evening through thursday)
issued at 345 PM MST Tuesday Mar 3 2015
A quick moving northern stream disturbance will move across
southeast Wyoming and southern Nebraska Panhandle this evening.
Some light snow is expected with this disturbance. Snow
accumulations will generally be on the light with an inch or
less. However...there will be a few localized instability bands
that could drop an inch or two of snow near the Interstate 80
corridor from around Laramie and eastward into the Nebraska
Panhandle. Otherwise snow will end from northwest to southeast
across most of the area this evening. A last gasp of light snow
possible near the southeast Wyoming/Colorado border after midnight with
little to no additional accumulation.
Wind chill values will continue to drop into the overnight hours.
Could see wind chill values near warning criteria in southeast
Wyoming...but as it stands now...expecting the need for a warning.
Into the Nebraska Panhandle it does look like wind chills will
reach into the advisory range. The plan now is to hoist a Wind
Chill Advisory this evening as the Winter Weather Advisory
expires. That of course assumes the forecast remains on track.
Skies will clear out late tonight into tomorrow with a sunny day
setting up. Temperatures will remain cold but the air mass will
begin to slowly moderate. The moderating trend will continue into
Thursday with no chances for precipitation but winds will start to
ramp up across southeast Wyoming Thursday afternoon...especially
west of the Laramie range.
Long term...(thursday night through tuesday)
issued at 300 PM MST Tuesday Mar 3 2015
A northwest flow aloft will hold over the region through this period with
Arctic air being forced well north over northern and eastern
Canada as the amplified pattern of recent flattens. A few weak
impulses may ride across the northern rockies into the northern
plains during the period but for now look to have little effect
on the sensible weather over the County Warning Area outside of varying amounts of
cloudiness. Temperatures will be on a general slow warmup during the
period as heights rise slowly with maximums possibly reaching the 60s
over at least the Panhandle by early next week. Winds look to be
fairly benign as well though some gusty periods possible around
the mountains at times...aided by any passing impulses.
Aviation...(for the 00z tafs through wednesday)
Fairly widespread MVFR conditions will persist over the terminals
through late this evening with 1 to 2 hour periods of IFR visible in
snow. This should continue tonight with clearing conditions from
north to south. VFR conditions are expected by 07z with winds
becoming light and variable.
issued at 520 am MST Tuesday Mar 3 2015
A winter storm will continue to impact much of southeast Wyoming
and the western Nebraska Panhandle through tonight. Significant
snowfall accumulations are likely along with strong northerly
winds resulting in extremely dangerous travel conditions. Very
cold temperatures are expected today and tonight with widespread
dangerous wind chills possible on early Wednesday morning.
Wyoming...Winter Weather Advisory until 9 PM MST this evening for
Winter Storm Warning until 9 PM MST this evening for wyz112-114.
NE...Winter Weather Advisory until 9 PM MST this evening for nez002-