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Area forecast discussion 
National Weather Service Cheyenne Wyoming
1142 PM MDT Thursday Oct 8 2015

Short term...(this evening through Saturday night)
issued at 408 PM MDT Thursday Oct 8 2015

Light rain showers continue this afternoon over eastern two-thirds
of the forecast area...with the best coverage across the
Nebraska Panhandle. Will see these showers continue through the
early evening as the upper level disturbance continues to move
overhead. A thunderstorm or two remains a possibility over the
mountains with the upper wave overhead...and as Li values are
slightly negative with cape up to 100 j/kg over the higher terrain.
Showers will come to an end this evening with east-southeast
upslope flow expected to bring stratus and patchy fog to some
areas across the plains. The likely areas to see these low clouds
are from the southern Laramie range Summit eastward along
I-80...and the Pine Ridge in Niobrara/Goshen/Sioux counties. Dense
fog...if it occurs...will be very localized in these areas.

Drier conditions are expected for Friday with breezy winds
developing in the afternoon as a shortwave moves overhead. Wind
directions in the high country will be out of the west...with
southwesterlies across the plains. Not much low-middle level moisture
will be associated with this looking at mainly some
middle- high clouds along with the breezy winds.

A stronger shortwave trough is prognosticated to move into the Pacific northwest
Saturday...then across the northern rockies Saturday night.
Temperatures will be quite warm on Saturday in the 70s and 80s with
breezy conditions expected once again in the afternoon. The
leeside trough will deepen as the shortwave treks east through
the day...and should induce stronger winds in the wind prone
areas along and west of the Laramie range through late Saturday

Long term...(sunday morning through thursday)
issued at 408 PM MDT Thursday Oct 8 2015

On Sunday a shortwave will move across into northern Wyoming. Probability of precipitation
will remain low...the GFS is showing mostly high clouds into
southeast Wyoming and the Nebraska Panhandle behind the shortwave.
Also...this shortwave will help to increase the pressure gradient
and produce high winds across southeast Wyoming. The GFS showing
winds near 45-50 kts at 750mb near Arlington and west of the
Laramie range. There is a potential for high wind headlines on
Sunday. Sunday's temperatures will be unseasonably warm with
highs into the upper 70 and 80s over the Nebraska Panhandle. The
rest of the week will cool slightly with west to northwest flow
prevailing. High temperatures are expected to be in the low to middle
70s with probability of precipitation remaining low throughout the week.


Aviation...(for the 06z tafs through 06z Friday night)
issued at 1135 PM MDT Thursday Oct 8 2015

Areas of fog and LIFR conditions will be possible through the
night over some of the Nebraska sites. VFR conditions will then
prevail after middle morning Friday. Winds through the period will be
less than 15 kts...except at rwl where southwest gusts to 20 kts
is expected on Friday afternoon.


Fire weather...
issued at 408 PM MDT Thursday Oct 8 2015

Light rain showers will continue over the plains this afternoon...with
an isolated thunderstorm or two still possible over the mountains through
sunset. Warmer and dry weather will build back in over the district
Friday through Sunday with warm and dry weather continuing into early
next week. Humidities are forecast to drop to the upper teens to middle 20s
across the district over the weekend...with some gusty winds likely
around the mountains in the afternoon. Gusts could be 30 to 40 miles per hour or higher
both days in this area...which will elevate fire weather concerns.


Cys watches/warnings/advisories...


Short term...rjm
long term...sml/kc
fire weather...rjm

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