textproduct: Pocatello

KEY MESSAGES

- Mild and pleasant afternoon highs through early next week.

- Dry conditions continue through Monday.

- Wetter and cooler conditions return for Thursday and Friday.

DISCUSSION

Issued at 1250 PM MDT Sun Oct 18 2026

A weak shortwave feature moving across the region will produce brief high cloudiness over Eastern Idaho today. Temperatures remain above seasonal normals into early in the week, with high temperatures reaching the mid-60s to low 70s across the lower elevations and Snake River Plain through Monday. Looking upstream on water vapor satellite imagery, a upper-level low near 45N/140W will approach the Pacific Northwest coast before dropping southward just offshore through mid-week. Deep southerly flow will develop across the Great Basin into Eastern Idaho, gradually drawing moisture northward into the region. Light, isolated to widely scattered showers may begin as early as Tuesday afternoon and continue into Wednesday, though precipitation during this initial phase will remain light and non-impactful.

The upper low shifts inland across Central and Southern California Wednesday night into Thursday as a deep split trough before ejecting northeast through the Great Basin through Friday. Deeper moisture is anticipated late Thursday into Friday, bringing a more organized and widespread surge of precipitation along with a sharp drop in temperatures. Exact timing and accumulation totals remain variable as ensemble guidance shifts the track of the system; however, confidence remains high in a transition to a significantly cooler and wetter pattern by the end of the week. Expect daytime highs to drop sharply by Friday, with snow levels lowering across higher terrain.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1053 AM MDT Sun Oct 18 2026

VFR conditions forecast under high pressure with just FEW high level clouds today, turning mostly clear by this evening. Winds will generally remain light and variable.

FIRE WEATHER

Issued at 149 AM MDT Sun Oct 18 2026

Today will be nearly a repeat of yesterday as far as temperatures, min RHs, and winds go across the area. Even Monday will have little to no forecast changes. On Tuesday, an isolated shower chance is introduced and will at least increase min RHs across the area. It's not until Thursday/Friday that we see bigger changes for the forecast as a low to our south brings Pacific moisture back to the area and troughing from the north brings in cooler temperatures. Expect a wet, cool end to next week.

PIH WATCHES/WARNINGS/ADVISORIES

None.