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000
FXUS65 KRIW 132030
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
230 PM MDT Sun Aug 13 2017

.SHORT TERM...(This evening through Wednesday)
Issued at 204 PM MDT Sun Aug 13 2017

As a Pacific low pressure trough over British Columbia, the Pacific
Northwest and Northern California moves east into the Northern Rockies
and Great Basin, west southwest flow aloft will increase across the
area bringing pacific moisture and scattered showers and thunderstorms
to the area tonight and Monday.  Convection will be strongest and
most numerous over the western and northern mountains. Small hail,
strong wind gusts and locally heavy rain will be possible. Tuesday
the trough will pass through the area with continued showers and
thunderstorms with colder temperatures as a cold front sweeps south
and east.  Cooler and more stable air will be over the area Wednesday
with decreased shower and thunderstorm activity.

.LONG TERM...(Wednesday night through Sunday)
Issued at 204 PM MDT Sun Aug 13 2017

As the Pacific trough moves east of the area Wednesday night and
Thursday, drying will occur.  Isolated showers and thunderstorms
will be possible in the north on Thursday, then a prolonged dry period
is expected Friday through Sunday with warming.  |

&&

.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 204 PM MDT Sun Aug 13 2017

VFR conditions will prevail through the forecast period. An upper
level disturbance moving across WY will continue widely scattered to
locally scattered showers and thunderstorms through early evening
along and west of the Divide...isolated to widely scattered east of
the Divide also through early evening. Storm and shower coverage
will decrease after 02z. Brief heavy rain, small hail and erratic
gusty winds G25-45kt can be expected at times. Additionally, brief
periods of MVFR in lower VSBY and CIGS will also be possible during
periods of heaviest activity. Mountains will be partially obscured
at times tonight. Another upper level disturbance will arrive across
western and northwestern WY Monday morning with showers and isolated
thunder possible over that area after 10z Monday morning...then
expanding across the northern half of WY by mid-day.

&&

.FIRE WEATHER...
Issued AT 204 PM MDT Sun Aug 13 2017

As a Pacific low pressure trough over British Columbia, the Pacific
Northwest and Northern California moves east into the Northern Rockies
and Great Basin, west southwest flow aloft will increase across the
area bringing pacific moisture and scattered showers and thunderstorms
to the area tonight and Monday.  Convection will be strongest and
most numerous over the western and northern mountains. Small hail,
strong wind gusts and locally heavy rain will be possible. Tuesday
the trough will pass through the area with continued showers and
thunderstorms with colder temperatures as a cold front sweeps south
and east.  Cooler and more stable air will be over the area Wednesday
with decreased shower and thunderstorm activity.  Afternoon mixing
and transport winds will support very good to excellent smoke dispersal
through Wednesday.

&&

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

$$

SHORT TERM...Baker
LONG TERM...Baker
AVIATION...Braun
FIRE WEATHER...Baker