Area Forecast Discussion
Issued by NWS Pocatello, ID
Issued by NWS Pocatello, ID
936 FXUS65 KPIH 140757 AFDPIH Area Forecast Discussion National Weather Service Pocatello ID 157 AM MDT Tue May 14 2024 .SHORT TERM...Today through Wednesday. Second shortwave arrives this afternoon. This shortwave is weaker than the one that passed through on Monday and convection is expected to be mainly limited to the lower/upper Snake Plain and eastern highlands. Storms overachieved on Monday with several severe level wind gusts noted. Unsure if we`ll see storms get that strong once again this afternoon. Storms will be firing earlier in the day, with most high res models showing initiation around 18z which could limit the strength of the storms with not as much heating likely to occur. Also the overall wind field looks a little lighter so there`s less wind to work with. Still, think that storms could be zesty with models showing some modest DCAPE to play with. Expect strongest storms to fire from Craters to Mud Lake and then move southeast across the Snake Plain, approaching Idaho Falls and Pocatello around 20z. Once again, CAPE looks limited to 1000 J/kg or less so think hail is not as much of the threat as wind would be. Most activity will be moving into Wyoming by 00z with an isolated storm or two still possible across the upper Snake Plain into the early evening. Lake wind advisory looks highly unlikely today with peak sustained winds expected to be around 15 mph from the west this afternoon. However, gusty outflows from thunderstorms could create rough chop. With the activity moving through earlier in the day, highs today look about 5 degrees cooler, roughly around 70 in the Snake Plain and Magic Valley. On Wednesday, can`t rule out a stray shower across the eastern highlands as the trough pulls away. Most of the region should be dry as a ridge starts to build into the area. Winds look downvalley across the Snake Plain and we could reach lake wind advisory on the weaker thresholds for northeast winds early in the day. However, models show winds become light around midday and even turning upvalley in the afternoon. So if we get to advisory levels the better chances are in the morning. Temps Wednesday are just a touch warmer with low to mid 70s likely across the Snake Plain and Magic Valley. 13 .LONG TERM...Thursday through next Tuesday. Thursday and Friday still look pretty breezy, with a few showers/storms possible up along the Divide. We will quickly flip the switch back the other way starting this weekend. Temperatures remain on the warm side as another low deepens and develops across the western U.S. While the are differences in the exact evolution, there is very good agreement between the GFS, ECMWF, and around 80% of the clusters through Monday. Those remaining clusters hold steadfast onto a ridge just to our west. Our Blend of Models forecast will show some lower chances of showers and thunderstorms with afternoon highs holding in the 60s and 70s. Breezy conditions are expected pretty much daily across our part of the state. Keyes && .AVIATION...Thunderstorms are the main concern this afternoon with storms likely impacting IDA and PIH around 20z, with some convection developing around the terrain at DIJ a couple hours earlier. Winds will start west or southwest at IDA and PIH, but convective outflows will likely push winds to the north or northeast by late afternoon with strong erratic gusts possible from the convection. Thunderstorm chances at KPIH and KIDA fall off quickly after 01z. KSUN and KBYI will likely remain storm-free this afternoon. Gusts to 25kts from the west are likely at BYI this afternoon. Considerable uncertainty in winds at KSUN for the afternoon with some models showing a weak front pushing through there this afternoon which would keep the winds northwest or west, while some models still show the typical weak upvalley wind developing this afternoon. 13 && .HYDROLOGY...The Portneuf and Blackfoot rivers remain the water ways of concern, though forecasts continue to trend down with water levels throughout the upcoming week despite a very slight uptick of water levels on the Portneuf River over the last 24 hours. McKaughan/13 && .PIH WATCHES/WARNINGS/ADVISORIES... None. && $$