


Area Forecast Discussion
Issued by NWS Pocatello, ID
Issued by NWS Pocatello, ID
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662 FXUS65 KPIH 230506 AFDPIH Area Forecast Discussion National Weather Service Pocatello ID 1106 PM MDT Thu May 22 2025 .KEY MESSAGES... - Dry and warming through Memorial Day in the Snake River plain and eastern Magic Valley. - Slight chance of showers and thunderstorms in the mountains and highlands for Friday afternoon and evening. - Slight chance of showers and thunderstorms Saturday afternoon for the eastern and southeastern highlands. && .SHORT TERM /THROUGH FRIDAY NIGHT/... Issued at 149 PM MDT Thu May 22 2025 This early afternoon radar images indicate scattered showers. Isolated thunderstorms are just now developing in a band along the western edge of the forecast area. This should continue this evening, then decrease to just showers in the late night. After this low moves through, high pressure should dominate the pattern, with strong heating making for some unstable conditions, so the slight chance continues for only the rough terrain. Afternoon highs should level off for Fri after the large amount of warming from Wed to today. The overnight lows warm from tonight to Fri night. Wind will be even weaker on Fri compared to today as the high pressure strengthens. && .LONG TERM /SATURDAY THROUGH THURSDAY/... Issued at 149 PM MDT Thu May 22 2025 The holiday weekend looks mostly pleasant across the region as troughing on Sunday looks to give way to weak ridging, or at least split upper flow, over the area which should keep things mostly dry. An isolated shower or storm is possible on Saturday across the eastern highlands but the rest of the area will remain dry. By the time we get into Sunday, it appears that there won`t be enough moisture to support much in the way of clouds, or precip, so ample sunshine is expected. Still seeing models struggle a bit with the amplitude of the aforementioned ridge so temps have come down a bit for Sunday with mid to upper 70s now forecast vs. the lower 80s from a few days ago. Still running slightly above seasonal norms but a noticeable downward trend nevertheless. Things SEEM like they want to warm up beginning on the Memorial Day holiday and continuing into the upcoming work week but models still show some differences in the upper level pattern as the ECMWF continues to show a slow-moving upper low through mid-week while the GFS shows an upper ridge strengthening over the area through the week. NBM continues with a middle of the road approach for now keeping temperatures in the lower 80s for valley locations with diurnal shower/storm chances, mainly across the high country, for much of next week and the forecast will run with this for now with slightly lower than usual confidence. && .AVIATION /06Z TAFS THROUGH 06Z SATURDAY/... Issued at 1106 PM MDT Thu May 22 2025 Overall forecast confidence continues to solidify in low-impact, VFR conditions dominating the current TAF period...and continuing into at least Saturday morning. The 00z HREF suite of CAMs have changed little...still supporting another round of isolated shower and thunderstorm activity Friday afternoon across northern portions of our forecast area including the Central Mountains and Montana border/Island Park region. Confidence remains very low as to whether or not any of this activity will be able to build far enough south to affect any of our TAF terminals, and we continue with a dry forecast. The best chance remains KSUN...perhaps a 20% chance at this time of at least a vicinity thunderstorm between about 19z/1pm and 01z/7pm. We`ll continue to evaluate this potential. && .FIRE WEATHER... Issued at 312 AM MDT Thu May 22 2025 Temperatures continue to warm today with highs into the 70s in the eastern Magic Valley and throughout the Snake River Plain and 60s elsewhere. A weak shortwave and cold front will be working through Eastern Idaho, too, bringing a chance for showers and storms mainly north of a line from Sun Valley to Idaho Falls to Driggs. Strong wind gusts up to 50 mph will be the main threat with any storms today, but it will also be breezy outside of storms with widespread gusts of 30 to 35 mph. Total QPF from any storms today is expected to remain around or below a tenth of an inch. && .PIH WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Messick LONG TERM...McKaughan AVIATION...01 FIRE WEATHER...AMM