FXUS65 KPIH 210321 AFDPIH Area Forecast Discussion National Weather Service Pocatello ID 921 PM MDT Sat Jun 20 2026 .KEY MESSAGES... - Periods of rain overnight mainly in eastern mountains. - Cooler overnight. - Continued cooler Sunday, but heating up quickly in the week ahead. && .DISCUSSION... Issued at 147 PM MDT Sat Jun 20 2026 A shortwave trough moving through Eastern Idaho today is bringing periods of showers, scattered storms, and gusty winds. It has cooled our temperatures by about 5-10 degrees from yesterday, too. We can expect breezy west winds to gust 30-40 mph this afternoon and any stronger storms that develop could produce gusty outflow winds up to 60 mph. A RED FLAG WARNING continues through the afternoon and evening due to these isolated to scattered thunderstorms. Cloud cover through the morning slowed our warm up just a bit, but now we are seeing some clearing and watching more storm development in northern Nevada and Utah as it moves into southern Idaho. This is also the area highlighted in SPC's Marginal Risk for this afternoon. Most recent runs of the CAMs show storms more confined to the South Hills and Southeastern Highlands and very limited activity up into the Snake River Plain until wrap around moisture moves through overnight. A few isolated showers and storms will linger through Sunday, mostly up north near the Island Park area, as the trough moves eastward. Highs on Sunday reach the upper 70s to low and mid 80s through most of the eastern Magic Valley and Snake River Plain and afternoon winds will gust around 25-30 mph. The heat continues to build through the week with highs reaching the upper 80s to low 90s for many by Tuesday and lasting through Friday. && .AVIATION /00Z TAFS THROUGH 00Z SUNDAY/... Issued at 520 PM MDT Sat Jun 20 2026 Areas of SHRA and TSRA ongoing across East Idaho late this afternoon. SUN looking at SHRA in the vicinity of the terminal per radar imagery, but each of the rest of the terminals VFR with no precipitation threat until later in the evening. Region of showers across the central mountains expected to shift east across the northern portions of the Snake Plain, impacting IDA by mid evening and the DIJ past midnight tonight. Gusty winds outside of the showers still gusting 35kts or stronger will decrease later this evening, becoming light and variable overnight. There is very weak potential for additional convection to develop Sunday afternoon, but confidence is very low for any of the terminals at this time, and have left forecast dry. && .FIRE WEATHER... Issued at 918 PM MDT Sat Jun 20 2026 Thunderstorms have ended so Red Flag Warnings have expired. Rain showers are forecast to persist into the night for portions of the Caribou-Targhee NF region. Drier conditions are forecast beginning Sunday as a weak ridge tries to rebuild into the Great Basin. Warmer temperatures are on tap as well as decreased daytime humidities. The next significant Pacific system that breaks down the ridge looks to arrive by next weekend, but there is uncertainty in how much moisture may be available for storm potential. && .PIH WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...AMM AVIATION...DMH FIRE WEATHER...GK