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Area forecast discussion 
National Weather Service Cheyenne Wyoming
1237 am MDT Sat Oct 25 2014

Short term...(this evening through Saturday night)
issued at 214 PM MDT Friday Oct 24 2014

Friday night-saturday:

Latest water vapor loop was showing the upper level ridge
continuing to dominate the region. This trend is expected to
continue during this timeframe. Temperatures were near or above
records in many locations this afternoon. This is due to good
downslope flow and very abnormal standardized anomalies at 700mb.
We are expected to continue to see this trend tomorrow...but it
appears like the downslope flow will not be as dominate as it was
today. The main reason is the upper level wave across the Pacific
northwest will begin to strengthen the Lee side trough somewhat
which will cause the low level flow to turn to the southwest. As a
result...we kept temperatures a couple of degrees cooler than

Saturday night:
a frontal boundary will be pushing through the area which will
cause the winds to turn to the west and favor some downslope flow
which may tend to offset the cooling somewhat. Not expecting any
precipitation along this boundary...due to limited moisture.

Long term...(sunday through friday)
issued at 214 PM MDT Friday Oct 24 2014

No big chances to the extended from last nights forecast package.
Models continue to show the system which is currently off the
northern California cost moving across the northern rockies late
this weekend and early next week. Subtle difference as to where
the main pieces of energy will track. The European model (ecmwf) indicates a
largely sheared apart system with only fragments of shortwave
energy moving over the forecast area. GFS showing a more organized
wave but keep the main forecast along the northern tier of the
forecast area and northward. Either way no big concerns with this
system. Generally kept probability of precipitation on the lower end...especially outside
of the mountains. Mild enough that the only real chances for
measurable snow will be into the mountains...mainly the snowy and
Sierra Madre ranges.

Northwest flow will set in on the backside of this weekends wave
and remain in place through Wednesday with several weak shortwaves
moving through the flow. Could see a few snow showers into the
mountains with passing shortwaves...but nothing more than virga or
sprinkles into the lower elevations. By late in the week the upper
level ridge will again build northward while sliding east. Looks
like dry mild weather will be in place next weekend.


Aviation...(for the 06z tafs through 06z Saturday night)
issued at 1232 am MDT Sat Oct 25 2014

VFR. Ridge aloft moves overhead this morning...then into the
Central Plains by Saturday evening. Weak surface gradients prevail
except for southwest winds gusting 22 to 28 knots this afternoon
at Rawlins and Laramie aerodromes.


Fire weather...
issued at 214 PM MDT Friday Oct 24 2014
gusty west winds at 15 to 25 miles per hour combined with unseasonably warm
temperatures created very low humidities this afternoon. Fuels are
susceptible to large fires in the Panhandle...but it appears like
the criteria will fall just short for red flag criteria this
afternoon. Tomorrow could be another day Worth watching with
regards to red flag criteria. Although...wind speeds should be a
bit lighter in response to the Lee side trough developing. On Sunday
night...a frontal boundary is prognosticated to push through the
area...but with limited moisture...we are not expecting much in
the way of precipitation. This will lead to cooler conditions on Sunday
which will favor higher humidity values.


Cys watches/warnings/advisories...


Short term...rec
long term...small
fire weather...rec

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