


Area Forecast Discussion
Issued by NWS Pocatello, ID
Issued by NWS Pocatello, ID
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414 FXUS65 KPIH 241723 AFDPIH Area Forecast Discussion National Weather Service Pocatello ID 1123 AM MDT Sun Aug 24 2025 .KEY MESSAGES... - Smoke from regional wildfires continues today. - Isolated showers and thunderstorms begin this afternoon south of the Snake Plain as moisture starts to increase from the south. - Monsoon moisture Monday through Thursday will bring scattered showers and storms daily, cooler temperatures, and measurable rainfall for many. && .SHORT TERM /THROUGH TONIGHT/... Issued at 124 PM MDT Sat Aug 23 2025 A check of satellite and radar early this afternoon shows a few isolated showers and storms pinwheeling northeast around high pressure in the Southwest and moving out of northeastern Nevada and northwestern Utah into parts of southern Idaho. This will continue this evening with these isolated storms mainly confined to parts of the South Hills, but a few will likely make it into parts of the Southeastern Highlands. Elsewhere, expect mostly dry conditions, highs in the upper 80s to mid 90s, and wind gust of 15 to 25 mph. This monsoon moisture will continue to increase through tonight and Sunday will see an uptick in storms, but coverage in the South Hills, Southeastern Highlands, and Central Mountains looks to remain isolated. The increasing cloud cover on Sunday will help keep temperatures just a few degrees cooler on Sunday and wind gusts will remain in the 15 to 25 mph range. Smoke from regional wildfires looks to filter back into parts of Eastern Idaho a bit more tonight and into Sunday. While it will likely be noticeable for all, an increased amount looks most likely in parts of the Central Mountains. At this point, air quality impacts look limited, but drops into the "Moderate" or briefly even into the "Unhealthy for Sensitive Groups" would not be a big surprise, particularly up around the Stanley and Challis areas. && .LONG TERM /MONDAY THROUGH SATURDAY/... Issued at 124 PM MDT Sat Aug 23 2025 Still on track for a prolonged period of clouds and rain across the region, beginning as early as Monday for most locations. Those areas that don`t see rain on Monday will almost certainly see some Tuesday and Wednesday with rain chances regionwide in the 70-90 percent range for those two days. When was the last time we had that?? It`s been awhile for sure. Monsoonal moisture throughout the region will keep clouds and rain chances prevalent Monday through Thursday with Tuesday afternoon to Wednesday evening looking like the most active period in the extended. Forecast QPF amounts generally range from 1/2 to 1 inch throughout the area through Thursday with some higher elevations spots currently forecast to see above 1 inch. As we`d expect with widespread clouds and rain, forecast highs run well below normal, especially for Wednesday with 60s and 70s expected. This pattern looks to change starting on Friday with the upper flow becoming more southwesterly again as weak ridging again tries to establish itself into next weekend. This should dry things out a bit and allow temps to slowly start to warm up into the Labor Day holiday weekend. && .AVIATION /18Z TAFS THROUGH 18Z MONDAY/... Issued at 1120 AM MDT Sun Aug 24 2025 VFR conditions with winds generally 10 kts or less today, although intermittent gusts to around 20 kts are very possible, especially at KPIH, KIDA, and KBYI. Mid-level and high clouds will continue to increase through the period as monsoon moisture begins to arrive. While isolated showers and thunderstorms are expected to largely remain near KBYI and further east and south today, terminals further north could see minimal activity ahead of more widespread showers and storms beginning Monday. HREF probability of thunder continues to run 10 to 20 percent today at KBYI with less than 10 percent elsewhere. Have retained VCSH at KBYI and KSUN, with confidence still too low to include at other terminals. Some hi- resolution models show a line of showers and potentially embedded lightning lifting northward overnight through sunrise Monday. However, considering lack of consensus in models and low confidence, have opted to omit any mention of this next round prior to 18z Monday at this time. && .FIRE WEATHER... Issued at 124 PM MDT Sat Aug 23 2025 It remains hot and dry today for most with just a few isolated storms in parts of the South Hills and Southeastern Highlands once again. Min RHs today are still in the 10 to 20 percent range with wind gusts around 15 to 25 mph. Our hot and dry weather pattern finally begins to break down on Sunday, so we will start to see some big changes moving into Eastern Idaho as monsoon moisture begins to arrive. Min RHs on Sunday will range from 20 to 30 percent in the southern half of our coverage area and from 15 to 20 percent in the northern half. At this point, thunderstorms on Sunday still appear to be mostly isolated in nature, but we will see some make it into the Central Mountains, too. While this will likely keep things below Red Flag Warning criteria on Sunday, it`s important to note these storms are more likely to be a mix of wet and dry storms before the bulk of the monsoon moisture arrives on Monday, so fire weather conditions will be elevated on Sunday, but not quite critical. Chances for a wetting rain will increase for Monday through Thursday, likely peaking on Wednesday. && .PIH WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...AMM LONG TERM...McKaughan AVIATION...Cropp FIRE WEATHER...AMM