Area Forecast Discussion
Issued by NWS Cheyenne, WY

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FXUS65 KCYS 122149

Area Forecast Discussion
National Weather Service Cheyenne WY
249 PM MST Mon Nov 12 2018

.SHORT TERM...(This evening through Tuesday)
Issued at 233 PM MST Mon Nov 12 2018

Outside the cold temperatures today and overnight, no impact
weather is expected through Tuesday. Below normal temperatures
today and overnight will occur but give way to a warming trend
starting tomorrow afternoon.

Well-below normal temperatures occurring this afternoon with
readings only in the teens in Laramie with other sites in the 20s
and 30s. These values are roughly 15 to 20 degrees below normal
for this time of year. As skies clear and with snow on the
ground for portions of the High Plains, expect a cold night ahead
with single digits in the higher terrain and mostly teens for the
High Plains of WY and NE. The -17C H7 temperatures will modify
upward overnight and Tuesday to near -3C to -5C and allow for a
better rebound into the 40s for highs. The warming trend will
continue through the rest of the week with above normal
temperatures expected. See long term discussion for more details
on the warmth and the next likelihood of snow late Friday into

.LONG TERM...(Wednesday night through Sunday)
Issued at 330 AM MST Mon Nov 12 2018

Long range models in generally good agreement, although there are
some noticeable timing differences with a surface cold front
forecast to move across the area late Friday and Saturday.
Otherwise, Expect a gradual return to near normal temperatures for
this time of the year with 700mb temps near or slightly below 0c,
which will result in highs in the mid 40s to mid 50s Thursday and
most of Friday.

Models indicate the next pretty strong cold front will begin
moving into the northern and central plains by late Friday, with
snow developing along and just behind the cold front. Mainly jet
dynamics and llvl upslope flow will drive dynamic forcing with
this event as widespread light snow is possible. There were some 6
to 12 hour differences in timing mainly with the 00z GFS, although
recent data is more in line with the ECMWF and ensembles at this
time. Models are also hinting towards the front stalling along the
mountains, which will likely result in higher snowfall rates
across portions of southeast Wyoming and the southern NE panhandle
through early Saturday. Will continue to keep an eye on this
since some travel impacts are possible late Friday and through


.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1025 AM MST Mon Nov 12 2018

With the introduction of drier air into the region, conditions
have improved out of IFR for all terminal sites. Conditions are
expected to remain at VFR through the period. Winds will be on the
decrease after sunset with clear skies to high clouds expected.


Issued at 233 PM MST Mon Nov 12 2018

Fire weather concerns remain minimal through the next several days
as humidity values remain above 30 percent while winds remain below
thresholds as well. Energy release components have plummeted to below
10% while moisture has increased with the recent snowfall across
the higher terrain. &&



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