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Area forecast discussion 
National Weather Service Cheyenne Wyoming
400 am MST sun Jan 25 2015

Short term...(today through Tuesday night)

Issued at 1257 am MST sun Jan 25 2015

A well-defined middle level shortwave continues to dive quickly across
the Central Plains early this morning. This system was responsible
for scattered rain and/or snow showers across much of southeast Wyoming
and the western NE Panhandle last evening. However...latest trends
in radar/Sat imagery indicate this activity has greatly diminished
in coverage as of 08z owing to increasing subsidence in the wake of
the departing wave. We are still seeing a few weak echos from kcys
along the Wyoming/NE state line near Scottsbluff...but potential for any
measurable precipitation is unlikely with drying low levels and larger scale
sinking motion overspreading the area. Low level gradients stay elevated
today with around 50 meters between cag-cpr at 850 mb. Fast northwest
flow aloft persists with a 130 knots h25 jet over eastern Mt/WY...so
the wind prone areas will undoubtedly be quite windy. A few wydot
sensors near Arlington have recorded winds near 50 miles per hour in the last
couple of hours...but do not expect warning criteria gusts as the
models suggest weakening flow aloft with time. A pretty uneventful
short term period aside from breezy conditions today. GFS/NAM/ecm
are in excellent agreement with broad upper-level ridging becoming
established on Mon/Tue. 700 mb temperatures are prognosticated to be around 5-7 degree c
at 00z Tuesday. No real concerns about cirrus either with fairly dry relative humidity
forecasts between h2-300 mb per the GFS. Adiabatic warming is likely with
good subsidence and westerly low level downslope...so tend to favor the
warmer MOS with highs around 65 f over the plains. Could see a few
records threatened early in the work week. Precipitation chances will be on
the increase over the far southwest on Tuesday night ahead of a strong
shortwave lifting across central Utah.

Long term...(wednesday through saturday)
issued at 300 am MST sun Jan 25 2015

Upper ridge that gave US the warm temperatures still forecast to
move into eastern Nebraska Wednesday morning. Shortwave trough
moves through Wyoming Wednesday afternoon for a return of colder
temperatures and mountain snow. By Wednesday afternoon...GFS 700mb
temperatures fall to -6c...down from +4c Tuesday afternoon.

Going to be windy with the associated cold front moving through
Wednesday. GFS 700mb winds 45 to 50kts...so likely to see wind
headlines for the wind prone areas. About .3 to .4 inches quantitative precipitation forecast for
the mountains out west with this system...so could see advisory
level snow amounts for the snowy and Sierra Madre ranges.

Another weak system for Friday that will bring some more light
snow amounts for the mountains. Most everywhere else should stay
dry with this system.

&&

Aviation...(for the 12z tafs through 12z Monday morning)
issued at 357 am MST sun Jan 25 2015

Latest hrrr guidance for the 12z tafs. Latest 11-3.9u satellite
imagery shows widespread stratus out by krwl this morning. Hrrr
shows the potential for this stratus to hang in around krwl for
most of the day. Some break up by middle morning shown...so went
sct008 after 15z. VFR conditions elsewhere.

&&

Fire weather...
issued at 1257 am MST sun Jan 25 2015

No major fire weather concerns. Warm temperatures and locally breezy
conditions are likely through Monday afternoon. All parameters are
expected to be well below critical thresholds.

&&

Cys watches/warnings/advisories...
Wyoming...none.
NE...none.
&&

$$

Short term...clh
long term...gcc
aviation...gcc
fire weather...clh

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