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Area forecast discussion 
National Weather Service Cheyenne Wyoming
537 PM MDT Wednesday Jul 27 2016

Short term...(this evening through friday)
issued at 324 PM MDT Wed Jul 27 2016

Convection is starting to deepen over the Laramie range and vicinity
this afternoon as expected, with cu starting to bubble over the Pine
Ridge and even the Cheyenne Ridge as well. Convective inhibition is
steadily waning, so expect convection to expand in coverage through
the evening as previously mentioned in the earlier update.

For tonight, a rather potent vort Max will ride over the forecast
area in continued northwest flow aloft. This will combine with a
weak llvl jet and forcing along the 700 mb front to maintain showers and
storms overnight, especially across the northern tier of counties.
Down south across the Cheyenne Ridge, stratus may develop in moist
upslope flow. For Thursday, models continue to show a favorable
setup for severe weather across the High Plains. A sfc trough,
perhaps remnant outflow boundary from tonight's convection, could
provide additional forcing in addition to the stalled boundary along
the Laramie range. Made only slight adjustments to pops and weather
from the previous shift's forecast as it was in good shape for what
models continue to depict for tomorrow. All modes of severe weather
are possible, even a couple tornadoes along the sfc/outflow boundary
if it pans out.

Friday should see a more isolated coverage of convection within a
weaker overall flow pattern. Upper level energy with persistent but
weaker upslope flow should spark off afternoon showers and storms.

Long term...(friday night through tuesday)
issued at 324 PM MDT Wed Jul 27 2016

Heights aloft will rise over the weekend across the region for a
drying/warming trend. There will still be quite a bit of llvl
moisture and instability across the Panhandle to the east of the sfc
trough, however the warmer air aloft/capping will limit tstm
coverage. Highs will be back up into the mid 80s to mid 90s over
lower elevations. Weak shortwave will move across Montana on
Monday, with a fropa during the morning. Best chances of storms
early next week will south of the area across Colorado. No
significant monsoonal moisture incursion is expected through Tuesday
with the midlvl subtropical ridge center located near The Four
Corners region.


Aviation...(for the 00z tafs through 00z Thursday evening)
issued at 516 PM MDT Wed Jul 27 2016

The main concern this evening is how long the convection will last

Latest radar loop was showing isolated convection mainly
southeast of kcys. However, some more storms were developing north
of Torrington. This may set the stage for more convection in the
Panhandle this evening. We are more confident about the kbff and
ksny taf sites for now based on radar trends. We will also need
to watch the convection spreading southeast from the Black Hills.
Kcys, klar, and krwl should stay in the clear through much of the
evening. Another shortwave is progged to push southeast through
southeast Wyoming later this evening and overnight and may trigger
more thunderstorms after midnight.


Fire weather...
issued at 324 PM MDT Wed Jul 27 2016

Breezy and dry conditions will prevail across the high country this
afternoon, with showers and thunderstorms developing in moist,
easterly upslope flow across the plains. Look for showers and storms
to occur through tonight. There remains a good chance for a more
scattered coverage of thunderstorms with wetting rains east of the
Laramie range Thursday, with isolated showers and thunderstorms
Friday and on through the weekend.


Cys watches/warnings/advisories...


Short term...rjm
long term...zf
fire weather...rjm

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