052 
FXUS65 KRIW 030851
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
251 AM MDT Sat Aug 3 2019

.SHORT TERM...Today through Monday night

As I write this around 2 am we still have a few showers and even a 
stray thunderstorm across northwestern Wyoming. These should end by 
sunrise though. All in all, today looks similar to Friday with hot 
temperatures and dry conditions for a vast majority of the area. 
Satellite imagery does show some moisture moving up from the south 
through Utah and this could be enough to bring isolated storms to 
southern portions of the area. However, warm mid level temperatures 
and a rather dry atmosphere at the surface should keep any storms in 
the isolated category. This will be the warmest day of the three as 
well, with a few locations approaching the century mark in the 
warmer locations like Greybull and Worland. Models are indicating 
some nocturnal activity in Johnson County as well so we kept some
isolated POPS there. With the large temperature / dew point 
spreads, any shower or storm that does develop could have strong 
wind gusts. This could turn out to be a dreaded "Little Green 
Blob" day in some locations.

The pattern looks to change Sunday into Monday as the ridge begins 
to flatten and more shortwaves to move over the top of it. For these 
days we have gone with isolated to scattered POPS across much of the 
area, with the vast majority of storms occurring in the afternoon
and evening. There also appears to be enough upper level support 
for some stronger storms on both afternoons as well. The Storm 
Prediction Center already has a marginal risk along and east of 
Interstate 25 for both Sunday and Monday. In addition, with the 
increased sky cover, temperatures will begin to lower. This will 
especially be so on Monday with most of the lower elevation seeing
high temperatures fall back into the 80s.

.LONG TERM...

High pressure ridging will continue across the region through next
week with a series of shortwaves bringing showers and
thunderstorms. Isolated to scattered convective activity will
develop in the afternoons, and then potentially last into the late
night hours. As usual, the best chances will be in and near the
mountains. Daytime high temperatures will be in the upper 70s and
low to mid 80s in the west, with the central basins and southern
regions in the the upper 80s and low 90s at times.

&&

.AVIATION...12Z Issuance

VFR conditions anticipated at all terminals through 12Z/Sunday. Mid-
level moisture will spread into southwest and far west Wyoming late 
Saturday afternoon. Expect much of this isolated, weak convection to 
remain across the mountains and far southwest near the Uinta 
Mountains. Confidence remains too low for inclusion in terminal 
forecasts. Surface wind speeds of 10 kts or less will prevail.
&&

.FIRE WEATHER...

Today will be a warm to hot and largely dry day across most of the 
area. Some moisture moving in from the south could bring an isolated 
shower or thunderstorm to southern Wyoming, but even here they 
should be few and far between. Relative humidity will fall into the 
teens at times in the lower elevations. However, winds will remain 
light to moderate except in and around any shower or thunderstorm. 
Mixing and smoke dispersal will generally range from fair in in some 
of the basins to good to excellent in western Wyoming.
&&

.RIW WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...Hattings
LONG TERM...Myers
AVIATION...Jones
FIRE WEATHER...Hattings