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Area forecast discussion...updated 
National Weather Service Cheyenne Wyoming
723 PM MDT Thursday Jul 2 2015

Update...for the early evening aviation update.

&&

Short term...(this evening through Saturday night)
issued at 251 PM MDT Thursday Jul 2 2015

Widely scattered showers and a few storms developing over parts of
southeast Wyoming this afternoon but not as much as was at this time
yesterday...likely due to less upper support. Should see a bit
more activity develop and move southeast into this evening before
dissipating tonight.

Little change seen in the overall pattern across the region Friday
through Saturday with a northwesterly flow aloft conducting periodic
ripples across the area. Should see widely scattered showers and storms
refire over the mountains Friday afternoon...moving southeast over the plains
through the evening. One feature will be a weak surface trough that
will begin to edge eastward over the High Plains Saturday.
Somewhat drier air behind this should act to reduce convective
activity over southeast Wyoming but may focus it over the Panhandle. Cape
values do go up over the plains Friday...generally in the
1000-1500 j/kg range...and over 2000 j/kg over the Panhandle
Saturday afternoon so a few stronger storms may result. Shear
values not all that high but still decent. Otherwise continued
warm Friday and even warmer Saturday as 700 mb warm about 2-4c.

Long term...(sunday through thursday)
issued at 251 PM MDT Thursday Jul 2 2015

Pretty strong cold front still on track to move into the area
Sunday evening into Monday morning. European model (ecmwf) 700mb temperatures fall
from +16c Sunday morning to +8c Sunday evening. Fairly widespread
showers and thunderstorms Sunday with the approach of this
front...especially Sunday evening. European model (ecmwf) showing well over an inch
quantitative precipitation forecast across the northern Panhandle and Niobrara County Sunday
evening. Did increase probability of precipitation to likely across the northeast.

A pretty cool day for Monday with the cold air behind the front
settling into the area. 700mb temperatures fall to +6c. Continued
to undercut guidance on temperatures. Cheyenne may struggle to
get out of the 60s Monday.

Another Canadian front looks to move into the area Tuesday night
into Wednesday. Pretty strong jet forecast to move into Colorado
Wednesday afternoon ahead of this front. Still looks like a pretty
good day for severe thunderstorms Wednesday afternoon/evening.
Still a ways out though and conditions could change.

Shortwave ridge for Thursday may give US a brief break in
showers. Mountains out west still the favored area for afternoon
and evening convection.

&&

Aviation...(for the 00z tafs through 00z Friday evening)
issued at 712 PM MDT Thursday Jul 2 2015

Scattered storms slowly weakening around Rawlins and Laramie...so
will leave thunderstorms in the vicinity mention in for those airports through 03z.
Midlevel cap seems to be holding across the Nebraska Panhandle so
will take out thunderstorms in the vicinity mention for those airports for this evening.
Otherwise...VFR overnight with scattered thunderstorms again
tomorrow afternoon with thunderstorms in the vicinity mention in for everyone except
Rawlins.

&&

Fire weather...
issued at 251 PM MDT Thursday Jul 2 2015

Fire weather concerns will remain low for the foreseeable future
with nearly daily chances for scattered mainly afternoon and
evening showers and thunderstorms. Winds will remain generally
light...though briefly gusty around storms. A monsoonal pattern
may set up next week which will keep chances for showers and
storms in the forecast.

&&

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

$$

Short term...re
long term...gcc
aviation...jg
fire weather...re

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