textproduct: Pocatello

KEY MESSAGES

- Daily chance of showers and thunderstorms through midweek with a mix of wet and dry thunderstorms

- Warmer temperatures will persist through next weekend

DISCUSSION

Issued at 103 PM MDT Sun Jul 5 2026

Showers and thunderstorms are ramping up as expected today and will persist each day through Wednesday. The best chance through this evening will be across the central mountains and eastern highlands. There is a MARGINAL RISK for severe thunderstorms across portions of the central mountains where there is 50-85% chance of gusts over 35 and possibly exceeding 60 mph. We are already seeing some decent downpours, so we do expect a mix of rain- producers and virga/sprinkles. Farther south, there is a decent area of mid level clouds. The potential of thunderstorms here is pretty low at the moment, although there is a 30-70% chance of gusts over 35 mph. This would indicate mainly virga/sprinkles or a light rain shower potential. This should diminish overnight as this surge of moisture shifts into Montana. For tonight and Monday, we will see plenty of mid level moisture and cloud cover across central and eastern Idaho. We will likely see some sprinkles or light showers overnight, but the chance is under 15%. If the trend continues later today, we may need to bump that up to 15-25% percent. Timing of this push puts the best chance of showers across the central mountains once again. Again, expect a mix of quick rain-producers and virga/sprinkles. Thunderstorm coverage will be highly conditional on where we get some sunshine tomorrow afternoon. The latest Blend of Models, and higher resolution probability forecasts want to produce scattered storms across the central mountains and down along the Utah border. There is a little more confidence to leave scattered across portions of the central mountains and isolated elsewhere. The reality of it with this type of pattern is that we may not get a true sense where storms form until tomorrow morning. The trend of some chance of rain and storms will persist through Wednesday. Highs should generally remain in the 80 to lower 90s as well.

We see clearing starting Thursday as a low to our north sweeps the monsoon push east and brings drier air across central and eastern Idaho. We should see an increase in gusty winds through next weekend. The airmass will be much warmer and drier as well. The trend continues to see high pressure building to our south and shifting north. There is still a 60/40 split in the clusters, as well as still some differences in the GFS and ECMWF. The favored trend is keeping the ridge far enough west to direct monsoon moisture away from our area, while the ECMWF and rest of the clusters set up a bit more southeast and allowing monsoon moisture to return, especially early next week. The Blend of Models is favoring the dry scenario, as well as hotter scenario. Highs are currently forecast in 90-100 range for the valleys by next weekend. The cooler scenario puts us back into the 80-90 degree range based on the range in the Blend of Models. The high end range in the Blend has mid 90 to around 105. This seems a bit high although the ridge is expected to be pretty strong. There is also an ongoing issue with high end temperatures being too extreme with the Blend forecasts.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1106 AM MDT Sun Jul 5 2026

Mid-morning visible satellite showing extensive but fairly transparent altocu cloud deck through southern Idaho. We'll continue to see this spread east northeast through the afternoon as moisture ticks upward ever so slightly. This additional moisture is expected to fuel a few showers and thunderstorms over the central Idaho mountains. By 21z we should see some convective initiation extending perhaps back southwest through KSUN. Confidence in any impacts to KSUN is fairly limited at this point. Higher confidence in the likelihood of temporary impacts exists in KDIJ where we should also see initiation off of the Big Holes and Snake River Range. Outside of these ports, we'll see only limited potential for showers in the vicinity of KPIH and KIDA.

Tonight after diurnally-driven showers/thunderstorms wane, we'll see some limited clearing, but VFR conditions will remain. Hi- res models show the arrival of another wave of showers in the pre-dawn hours associated with a weak upper-level wave arriving from southwest of our area. Will include a few VCSH for now for KBYI and KSUN Monday morning, but will need to revisit the potential in subsequent TAF packages.

FIRE WEATHER

Issued at 103 PM MDT Sun Jul 5 2026

High pressure and mostly clear sky conditions has brought summer- like temperatures back to the area. Now that ridge of high pressure is beginning to erode as an upper-level wave passes through south and central Idaho today and tonight. The result of these warm temperatures and passing disturbance is an increase in instability and fuel for showers and thunderstorms, particularly over the central Idaho mountains this afternoon and evening. Extremely dry low-levels and instability would allow for intense fire behavior, should one establish this afternoon/evening. Stronger showers or thunderstorms should be able to lead to gusty outflow wind conditions with gusts greater than 40mph possible in the stronger storms. Outside of this threat, winds should largely be limited.

We'll continue to see a modest uptick in moisture availability Monday and Tuesday which should fuel additional shower and thunderstorm activity. Depending on timing of the disturbance and the subsequent convective development, we could see scattered thunderstorms over the central mountains. However, fuel conditions over zones 475, and 476 have not been as receptive as other fire zones south and east where thunderstorm coverage will be more limited.

Midweek will bring a period of transition back towards warming and drying conditions. We'll see several days of tightening of the pressure gradient leading to more wind Wednesday and Thursday. RH values look to be marginal Wednesday, but continued drying Thursday means that RFW conditions will likely come back to the area. Thereafter, conditions only become hotter and drier with temperatures into next weekend at least 8-10 degrees above normals, where readings in the 90s will be common across the lower terrain.

PIH WATCHES/WARNINGS/ADVISORIES

None.