


Area Forecast Discussion
Issued by NWS Pocatello, ID
Issued by NWS Pocatello, ID
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837 FXUS65 KPIH 291952 AFDPIH Area Forecast Discussion National Weather Service Pocatello ID 152 PM MDT Fri Aug 29 2025 .KEY MESSAGES... - Isolated thunderstorms this afternoon and evening. - Turning drier and a little warmer for Labor Day weekend. - Dry pattern continues through most of next week. && .SHORT TERM /THROUGH SATURDAY NIGHT/... Issued at 152 PM MDT Fri Aug 29 2025 Satellite imagery shows pair of weak shortwaves impacting East Idaho this afternoon. The first shifting into the state from Oregon/Washington, helping to fire isolated thunderstorms across portions of the central mountains, mainly south of the Lost River Valley. Second shortwave sliding across northern Nevada/Utah this afternoon helping to fire a few thunderstorms across the southern/southeast highlands. High-res models particularly HRRR and WRF picked up on the central mountain development, but all of them missed out on the development across the south where weakly northwest flow providing some additional orographic help. WRF was the closest, but still kept bulk of the convection south of the UT border and a few hours later. Have adjusted PoPs this afternoon and early evening to try to account for these areas. Also some concern for the central mountain convection to spill out into the Snake Plain late this afternoon into the evening, and even if it doesn`t, will also be keeping an eye out for outflow boundaries that traverse the Snake Plain toward the I-15 corridor, just enough for minor impacts but not expected to approach severe. Both HRRR and WRF also keep some convection going after 03Z, but opted to allow PoPs to drop off after that time period, for now. Remainder of tonight looks dry and continued cool, but seeing some very weak low confidence potential of isolated development on Friday across the central mountains once again. There is less of a signal on less of the high- res cams, and NBM maintains dry conditions. If anything, believe this would be more favorable for an isolated sprinkle from an over-zealous cumulus rather than a thunderstorm concern. && .LONG TERM /SUNDAY THROUGH THURSDAY/... Issued at 152 PM MDT Fri Aug 29 2025 Models remain bullish on development of strong ridge through the Great Basin into Idaho for the Labor Day weekend, continuing well into next week. There are some differences in the ensemble clusters with regard to how much influence the low off the Pacific coast will influence the coast, and thus there are some very minor differences in how much convective potential can be realized any particular afternoon, especially for Tuesday and beyond. The NBM means have backed off considerably on any kind of mention of thunderstorms until late next week, but the 90th percentiles QPF do develop some very light amounts each afternoon across higher elevations, so still can`t completely rule it out at this time. Daytime highs still look stable with daytime highs remaining in the 90s throughout the period. && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 1211 PM MDT Fri Aug 29 2025 VFR expected to mostly prevail through the period with mostly clear skies and light winds into Saturday afternoon. There is a slim possibility of seeing some shower/storm development later today that could impact KSUN, KIDA and KPIH but potential is fairly low. Removed the PROB30s from the forecast and just show VCSH/TS at the aforementioned locations to at least show this low potential through the mid afternoon to late evening hours. After this, skies should become mostly clear into the day tomorrow with no precipitation expected over the upcoming holiday weekend. && .FIRE WEATHER... Issued at 152 PM MDT Fri Aug 29 2025 Drier weather is slowly taking hold over the region although we will have one more day of at least some isolated precipitation chances before drying out for the holiday weekend and continuing into early next week. Expect some isolated showers/storms to develop this afternoon and evening, especially over terrain, with these diminishing as we get to around sunset. The weekend looks dry as high pressure settles over the area and temps will gradually rise accordingly to around seasonal levels. This should keep wind and RH concerns low as we move into the first week of September. && .PIH WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...DMH LONG TERM...DMH AVIATION...McKaughan FIRE WEATHER...McKaughan