textproduct: Pocatello

KEY MESSAGES

- Dry conditions and lighter winds today and Friday

- A mix of wet and dry thunderstorms expected Saturday. A Fire Weather Watch is in place for portions of East Idaho.

- ABOVE AVERAGE temperatures expected well into next week

DISCUSSION

Issued at 131 PM MDT Thu Jun 18 2026

Satellite imagery shows broad northwest flow with weak upstream ridge in place from Nevada to Oregon. High level moisture streaming through the flow shifting into the region this afternoon and evening. Moisture begins to work around the ridge Friday ahead of Pacific shortwave trough arriving Saturday. There is low confidence potential of weak convection trying to develop late Friday across the southern highlands. Very dry low level conditions would indicate early potential is more likely to produce isolated pockets of virga. Chances increase through the overnight and have nudged precipitation chances up especially across the north. Better chances for thunder arrive Saturday across the region, with QPF still ranging 0.10-0.25" across the central mountains east to generally the Big Hole range north. Lesser amounts are expected throughout the Snake Plain and south, though an isolated storm could produce wetting rain. Saturday looks breezy as well, with gusts topping out in the 30-40mph range through the Snake Plain. While some of this may be convectively influenced, there may be enough wind to necessitate a LAKE WIND ADVISORY. Shortwave axis shifts through early Sunday, shifting most of the precipitation chances east except for the Yellowstone/Island Park region. East Idaho remains under the influence of the upper trough moving into the early portion of the week, but there appears to be limited moisture available to produce any further precipitation.

Shallow ridge tries to redevelop through much of the remainder of the week, bringing a slight warming trend back to East Idaho. Lower elevations warm back into the 80s and lower 90s by mid week next week. There is some hint of a shortwave trying to drive through the PacNW and Northern Rockies by late week, but there is still quite a bit of uncertainty regarding any precipitation potential at this time.

AVIATION /06Z TAFS THROUGH 06Z SATURDAY/

Issued at 1024 PM MDT Thu Jun 18 2026

Will have continued widespread VFR conditions through Friday evening with only mid and high level clouds. Light winds overnight tonight with some 10 knot speeds at PIH, IDA and DIJ Friday afternoon with some gusts approaching 20 knots.

FIRE WEATHER

Issued at 131 PM MDT Thu Jun 18 2026

FIRE WEATHER WATCH issued for Fire Weather Zones 410, 413, 422, 427, 475, and 476 on Saturday due to scattered thunderstorms. More below...

While gusty winds have finally diminished across eastern Idaho, the very dry conditions continue today and tomorrow. Parts of Fire Weather Zones 413, 425, 425, and 476 are forecast to have min RHs fall into the upper single digits this afternoon and everywhere else will fall into the 10 to 20 percent range. On Friday afternoon, min RHs will only increase by a couple of percentage points, but generally staying within the 10 to 20 percent range. We will still be seeing near-critical fire weather conditions for these two days with wind gusts of 20-25 mph and these low RHs. There's about a 50 to 70 percent chance of a portion of FWZ 425 between Richfield and Craters of the Moon reaching RFW criteria for a brief period this afternoon, but it is not a widespread enough area to warrant a full RFW for the whole zone.

Friday into Saturday a shortwave trough begins to enter our area and brings a few isolated showers beginning Friday afternoon, though thunder potential Friday PM looks low, less than 10 to 15 percent. Showers and thunderstorms become more scattered on Saturday as the trough itself moves through and it will be a mix of wet and dry storms. Due to the scattered activity, a FIRE WEATHER WATCH has been issued this afternoon for FWZ 410, 413, 422, 427, 475, and 476 from 9 AM to 9 PM Saturday. The current plan is to upgrade that to a RED FLAG WARNING on Friday afternoon. Timing of the headline is subject to chance pending subsequent model runs.

On Sunday, a few isolated showers and storms linger in the Eastern Highlands/Island Park area as the trough moves eastward. Next week, RHs drop quickly as we dry out and even with a few shortwaves passing through during the week, nothing looks to bring much precipitation, but likely brings some wind, so we will watch for more RFW potential towards the middle of the week.

PIH WATCHES/WARNINGS/ADVISORIES

Fire Weather Watch from Saturday morning through Saturday evening for IDZ410-413-422-427-475-476.