991 FXUS65 KRIW 142311 AFDRIW Area Forecast Discussion National Weather Service Riverton WY 510 PM MDT Wed Jul 14 2021 .SHORT TERM...(This evening through Thursday night) Issued at 204 PM MDT Wed Jul 14 2021 Today is much quieter than yesterday. Cooler and dry conditions will continue across the region with mainly light winds through the remainder of the day. The fog and low clouds across eastern areas this morning has since burned off. A few isolated showers and the occasional thunderstorm may occur across mainly central areas later this afternoon, but CAMs are not getting excited about much development. Best chances for convective initiation will be along the southern Absarokas, Winds and the Owl Creeks. The Bighorns may see some cumulus development, bust again, nothing significant. Most of the showers will be no more than a passing virga shower, especially across the south and central basins where there is little moisture to work with. Tomorrow, the ridge begins to build in. This ridge will dominate the forecast through at least the next week, but more on this in the extended forecast. Tomorrow will see greater chances of monsoonal showers and thunderstorms, but still not looking at anything significant by any means. Slightly stronger northwest flow will occur tomorrow so some areas will see a bit of a northwest breeze during the afternoon and early evening hours. This will mainly occur down the Wind River Basin and Green River Basin. Fire weather conditions will be elevated with the gustier winds, but not critical. The one other thing to mention is the continuing smoke and haze across the area. Conditions across the west will be more favorable today for plume dominated fires, so the large fires in Oregon, Washington, and Idaho that have been puffing their smoke in our direction, will continue to do that today. A thicker plume will likely move into the west tomorrow, leading to reduced visibility. The western valleys continue to be the biggest area of concern for smoke impacts. .LONG TERM...(Friday through Wednesday) Issued at 204 PM MDT Wed Jul 14 2021 Models continue to build the H5 ridge across the region, drawing northward across Wyoming. Stronger capping won't really start until Saturday, so a few thunderstorms will still be a threat across higher elevations on Friday. Once the ridge anchors in place in the vicinity, temperatures will clime well into the 90s and low 100s. Long range models continue to keep the ridge in the vicinity through the middle of next week. Only question is whether the next trough to the west or the low cutting off across the Four Corners can nudge the ridge away far enough to let the higher elevation thunderstorms fire again. Right now this ridge looks strong enough to avoid this through at least the middle of next week. && .AVIATION...(For the 00Z TAFS through 00Z Friday) Issued at 500 PM MDT Wed Jul 14 2021 Most terminals will remain dry with VFR through the period. Very isolated evening thunderstorms are possible in far south Wyoming. Mostly light wind will also occur at the terminals. Smoke will continue to impact KJAC with occasional MVFR visibility. Smoke will also create mountain obscuration through the period. Some isolated showers and thunderstorms are possible Thursday afternoon, but there is not enough confidence to include at any terminal. Winds will also increase a bit tomorrow afternoon, mainly at KBPI, KPNA, and KRKS. && .FIRE WEATHER... Issued AT 204 PM MDT Wed Jul 14 2021 Hot and dry conditions will dominate the remainder of the week and into the upcoming weekend. Afternoon humidity levels will fall below 15 percent for most areas each afternoon, with localized areas falling below 10 percent. Winds will reach 15 to 20 mph during the afternoon through Friday, with lighter winds expected over the weekend. A weak weather system Thursday will bring isolated showers and thunderstorms on the higher mountain ranges, with some lightning threat possible. These showers will quickly dissipate during the evening hours. && .RIW WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...Fisher LONG TERM...Straub AVIATION...Fisher FIRE WEATHER...Straub