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Area forecast discussion 
National Weather Service Cheyenne Wyoming
357 am MDT Monday Jul 6 2015

Short term...(today through Wednesday night)
issued at 357 am MDT Monday Jul 6 2015

Right rear of an upper level jet and positive vorticity advection
ahead of an upper level trough is producing showers across the
forecast area at this time. Also seeing some pockets of fog and
drizzle due to a saturated boundary layer and upslope low level
flow along and just east of the Laramie range. Shower activity
will generally shift east of the forecast area by middle morning as
the main dynamics move into the upper Midwest. Fog and drizzle
potential will also wane through the morning hours. Cloud cover
and cool boundary layer will keep chances for precipitation and
thunderstorms at a minimum east of the Laramie range today. To the
west a few afternoon thunderstorms are expected...mainly over
Carbon County. Severe thunderstorms are not likely but small hail
and heavy rain may be possible.

Shower and thunderstorms will mostly die off this evening but a
few may linger across the west as a weak wave moves across
southern Wyoming. Chances for showers and thunderstorms will
increase Tuesday into Wednesday as an nearly continuous stream of
weak shortwave impulses moves through westerly flow aloft. Mostly
cloudy to cloudy skies will be in place through Wednesday night.
Cloud cover and shower activity will hold daytime temperatures
down...making for relatively cool highs as compared to normal for
early July.

Long term...(thursday through sunday)
issued at 357 am MDT Monday Jul 6 2015

Active west to southwesterly upper flow will keep chances for
showers and thunderstorms elevated through Thursday. As we head
into the weekend...both the GFS and European model (ecmwf) depict a dry pattern
for southeastern Wyoming and the western Nebraska Panhandle as
they retrograde the Southern Plains ridge westward into the
central rockies...pushing the active portion of the middle/upper flow
to our north. So...we keep chance probability of precipitation going on Thursday then
taper down to very low probability of precipitation by Saturday. By the weekend...we will
be back to pushing lower 90s in the western Nebraska Panhandle
with middle/upper 80s in southeast Wyoming except 60s to lower 70s in
the higher elevations.

&&

Aviation...(for the 12z tafs through 12z tuesday)
issued at 400 am MDT Monday Jul 6 2015

We still have scattered rains pushing southeastward across the
forecast area early this morning...with areas of drizzle...fog and
IFR ceilings in for some locations from Cheyenne east into the
Nebraska Panhandle. We expect low ceilings and patchy precipitation
to continue through late morning before any improvement up to MVFR
or IFR.

&&

Fire weather...
issued at 400 am MDT Monday Jul 6 2015

No critical fire weather concerns through this week as a wet
weather pattern will remain in place. Temperatures will be below
normal with above normal precipitation.

&&

Hydrology...
issued at 357 am MDT Monday Jul 6 2015

Pockets of heavy rain produced some flash flooding into Morrill
County Nebraska Sunday evening. While the waters have receded...
some standing water may remain over the next day or so.
Fortunately once showers end this morning dryer conditions will
be in place for the next 36 to 48 hours. Showers and thunderstorms
are again expected Tuesday night into Wednesday night with locally
heavy rain not out of the question. While the wet weather pattern
is likely through Friday...the weekend is starting to look
promising with drier air moving into the region.

&&

Cys watches/warnings/advisories...

Wyoming...none.
NE...none.

&&

$$

Short term...small
long term...jg
aviation...jg
fire weather...small
hydrology...small

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