003
FXUS65 KRIW 011014
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
414 AM MDT Mon Jul 1 2024

.KEY MESSAGES...

- A cold front today brings cooler temperatures and rain
  chances, mainly across the northern half of Wyoming.

- Rain chances for northern Wyoming through midweek, with cool temperatures.

- Warm and dry conditions looking more likely into next weekend.

&&

.DISCUSSION...
Issued at 139 AM MDT Mon Jul 1 2024

A cold front moves through the area today. As a result, it will be
noticeably cooler, especially compared to the highs yesterday that
were in the 90s for many locations, with a few 100s noted. Highs
today peak in the 70s for most, with some low 80s in central
Wyoming. This front also brings the chance of rain. As it sweeps
through the area this morning, a line of showers and storms
accompanies it. The most likely places to get rain are across
northern Wyoming. As the line tracks southeastward, lesser chances
occur over the basins, such as the Green River and Wind River
Basins; chances for these places are more in the 20% to 30% range.
The best chances continue across the northern part of the state
through the day as broad trough influences the area. Outside an
isolated (about 20% chance) shower, southern Wyoming should remain
dry. Some of the storms across the north (mainly the Bighorn Basin
and Johnson County) could be on the stronger side, with gusty
outflow wind or hail. The better chances for strong to severe storms
occurs towards Johnson County and northern Natrona County.

A tight pressure gradient persists today as well, with afternoon
wind gusts 30 to 40 mph across the Wind Corridor, and lesser gusts
elsewhere. These gusts decrease into tonight. Precipitation
continues across the north tonight as the broad trough remains in
place. They should be on a decreasing trend, however, by Tuesday
morning. Isolated (15% to 30%) chances continue across the north
Tuesday, mainly over the mountains. Highs Tuesday will be similar to
that of today, maybe a few degrees higher.

An upper-low moving down from Canada and into the Dakotas brings
moisture ahead of it on Wednesday. Rain chances (20% to 50%) occur
over far northern Wyoming during the afternoon and evening. This
also brings a breezy to windy afternoon. As this low continues to
move down, cooler air makes its way into the area for Thursday, with
highs back into the 70s. Rain chances also continue across the north
and portions of central Wyoming. The night of the 4th is currently
looking dry as the afternoon convection ends around sunset
Thursday, but some lingering showers cannot be ruled out at this
time.

High pressure begins to build in over the western U.S. for this
weekend, favoring warmer and drier conditions. Long range models are
showing the possibility for some systems to pass over eastern
Wyoming, which may bring some rain chances; confidence is low at
this time.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 410 AM MDT Mon Jul 1 2024

VFR conditions to start the period for all TAF sites and should
remain so throughout. A cold front will push through the CWA
this morning with light rain showers at JAC shortly after the
start of the period for this morning. More widely scattered rain
showers and thunderstorms this afternoon with highest confidence
locations a tempo group after 20-21Z through about 01-03Z.
Lowest confidence only carrying VCTS during this timeframe at
LND, RIW, WRL, and RKS. Models indicate a sporadic coverage in
these areas but this should all diminish towards sunset.
Otherwise, mid level ceilings will lift to the upper levels
scattering out west of the Divide overnight with light winds
into Tuesday morning.

Please see the Aviation Weather Center and/or CWSU ZDV and ZLC for
the latest information on smoke, icing, and turbulence
forecasts.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...Wittmann
AVIATION...Lowe