textproduct: Pocatello

KEY MESSAGES

- A mix of wet and dry thunderstorms expected Saturday. A Red Flag Warning is in place for portions of East Idaho.

- Breezy and cooler Saturday.

- ABOVE AVERAGE temperatures expected well into next week

DISCUSSION

Issued at 126 PM MDT Fri Jun 19 2026

WV satellite imagery shows shortwave feature ejecting northeast out of northern California across East Idaho by Saturday. Very warm temperatures continue today, with afternoon and evening build ups that could produce a few virga showers with a sprinkle or two and gusty outflows around 35 mph. Most of the convective activity should stay to the west today, but shower activity begins to increase during the overnight and would not be surprised to see a few lightning strikes approaching sunrise or just after. High-res models still appear to favor a line of weak convection developing north-south and pushing northeast through the Snake Plain early in the day, and HRRR shows gusty outflows 35-40 mph with this feature. As PW continues to increase through the day, the chance for thunderstorms with wetting rains increases, particularly across the northern higher elevation zones. In addition, gusty winds remain a threat, and could approach severe limits moving into the late afternoon. Precipitation amounts still range from 0.10-0.25" across the northern tier higher elevation zones, decreasing to much lower amounts below 0.10" through the Snake Plain and south. That said, the potential for brief heavy rain remains for the afternoon and evening. Wind speeds look to be sufficient to support the headline, but recent guidance indicates more a westerly cross-reservoir direction to the wind at the surface, reducing the risk of dangerous chop. Thus will hold off for now. Shortwave continues to shift east Saturday night into early Sunday. There is some potential for continued convection overnight, especially across the northeast corner of the region. East Idaho stays under the influence of the upper trough through Monday, but much drier conditions are anticipated. We do see an upper ridge rebuilding through the middle of the week. We could see moisture working around the ridge as early as Wednesday or Thursday, but models seem content to keep all of East Idaho dry for now. Otherwise expect a return to a warming trend for Tuesday through the rest of the week with temperatures bumping into the lower 90s for some areas by Wednesday.

AVIATION /06Z TAFS THROUGH 06Z SUNDAY/

Issued at 1145 PM MDT Fri Jun 19 2026

Main impact today will be upper level system working through Idaho and expect convective activity and have vicinity showers and thunderstorms at all sites through today and this evening. Expect steadier rain overnight at DIJ. Winds will pick up in the afternoon with 10 to 20 knots sustained with gusts 25 to 30 knots with higher gusts near thunderstorms.

FIRE WEATHER

Issued at 126 PM MDT Fri Jun 19 2026

A RED FLAG WARNING is in effect for Fire Weather Zones 410, 413, 422, 427, 475, and 475 from 6 AM to 9 PM on Saturday for scattered thunderstorm activity.

As a shortwave trough moves into south central Idaho this evening, there will be an increasing potential for isolated virga showers/dry thunderstorms. This is only about a 10 percent chance and mostly confined to portions of Fire Weather Zone 427. However, as the trough moves eastward overnight into Saturday, thunderstorm activity will become more widely scattered, so have issued the RED FLAG WARNING mentioned at the top of this discussion. These will be a mix of wet and dry storms tomorrow, with the wetter storms farther north into zones 475 and 476 and the northern half of 422. The NBM shows about a 50 to 70 percent chance of 24 hr QPF exceeding 0.10" ending 6AM Sunday. It is a similar potential from Rigby up to Island Park. In these same areas, it's about a 25 to 50 percent chance of QPF of at least a quarter inch. Zone 411 will see these scattered storms, but fuels are not yet approaching or at critical in this area, so it is not included in the RFW. Storms will be drier in FWZs 410, 413, and 427. And although 425 isn't in on the RFW "fun," it will still experience some isolated thunderstorm activity. Winds will be breezy even outside of storms, with gusts around 35 mph, but outflow winds from storms could be pushing 55 mph at times.

A few isolated showers and storms will linger into Sunday in the Island Park area, but the rest of eastern Idaho dries out quickly and begins to heat up once again. Wind gusts will range from 20 to 30 mph on Sunday in much of the eastern Magic Valley and Snake River Plain as min RHs drop back to 10 to 15 percent, so back to near- critical fire weather conditions for winds and RHs. While it won't be quite as breezy elsewhere, we will still have to watch for any holdovers from Saturday's storms.

PIH WATCHES/WARNINGS/ADVISORIES

Red Flag Warning from 6 AM to 9 PM MDT Saturday for IDZ410-413- 422-427-475-476.