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Area forecast discussion
National Weather Service Riverton Wyoming
338 PM MDT sun Jul 21 2019

Short term...(this evening through monday)
issued at 150 PM MDT sun Jul 21 2019

500 mb ridge continues building northward during the next 36 hours,
capping off most of the atmosphere across Wyoming. At the sfc,
the return of southerly flow across Wyoming will mark the return
of hotter conditions, with Monday temperatures a good 5 to 10
degrees above today's high temperatures. With the return of some
moisture back into the Wind River and Big Horn basins, some shower
activity is possible during the peak heating hours, but will have
to contend with the aforementioned capping inversion. Kept best
rain chances across the absarokas, which are farther away from the
core of the midlevel ridge.

Long term...(monday night through sunday)
issued at 150 PM MDT sun Jul 21 2019

Even with an established ridge in place there will be enough
moisture for isolated showers and thunderstorms on Tuesday
afternoon, especially across the north. By Wednesday the ridge
will begin to break down, with a cold front moving across the
area. Isolated convection will possible through Thursday but
mainly limited to higher elevations. Friday currently looks warm
and dry, but moisture will return by the weekend. Models continue
to show a shortwave in relatively zonal flow kicking off perhaps
more widespread convection coverage on Saturday and Sunday.
Despite the chances for thunderstorms each day, many locations
will remain dry. This means continued drying of fuels, and coupled
with lightning and gusty outflow winds, fire weather conditions
will need to be closely monitored.


Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1136 am MDT sun Jul 21 2019

Breezy conditions will occur east of The Divide today. Very
isolated afternoon and evening showers and thunderstorms are possible
over far eastern and southern Wyoming but impacts to terminals
currently look minimal.


Fire weather...
issued at 150 PM MDT sun Jul 21 2019

What's left of the front across southern Wyoming will dissipate
tonight, allowing southerly flow to return areawide. This will
allow for higher temperatures on Monday, which in turn, will lead
to slightly lower humidity levels. There may be some thunderstorm
activity for the absarokas during the afternoon Monday, which
would bring variably gusty winds. Mixing and smoke dispersal will
be fair to good east of The Divide, and very good to excellent
west of The Divide.


Riw watches/warnings/advisories...


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