textproduct: Pocatello

KEY MESSAGES

- Combination of Freeze Warning and Frost Advisory in effect for our growing zones through 9 AM Monday, with frost/freeze headlines necessary the next few mornings.

- Temperatures gradually warm into above-normal territory throughout the week.

- Breezy conditions will return areawide this evening and overnight with a Lake Wind Advisory in effect for breezy north to northeast winds over the American Falls Reservoir.

DISCUSSION

Issued at 142 PM MDT Sun May 17 2026

Upper trough in place over East Idaho today. A few showers ongoing over the eastern highlands, with more consolidated region of precipitation located over northern Nevada and portions of Utah late this morning. As center of upper low continues to work east through Utah through tonight, expect precipitation to work north into the southern and eastern highlands. 2-4" of snow is anticipated across the Bear River range and higher elevations east to the Wyoming border tonight through Monday.

Northerly surface gradient today increases into tonight. Winds this afternoon should be strong enough to support chop near the dam on American Falls Reservoir, therefore a LAKE WIND ADVISORY remains in place for daytime boating hours. The winds continue to increase during the overnight, peaking between roughly 9pm and 3am across the northern portions of the Snake Plain. Winds MAY approach or exceed lower end advisory thresholds, but will hold off on additional headlines for tonight. Most guidance remains below advisory thresholds at this time, and overnight occurrence should minimize travel impacts across the region. The only remaining immediate impact will be the cold overnight lows tonight and especially Monday night across the region. A mix of FREEZE WARNING and FROST ADVISORY is in place for tonight, with the coldest temperatures aligning well with the strongest winds between Craters of the Moon and Mud Lake. Temperatures along the interstate corridor still look to remain above freezing overnight. Another round of cold temperatures is forecast for Monday night, with temperatures dropping a few degrees colder than tonight, supporting potential FREEZE WARNINGS for the entirety of the Snake Plain once again.

For the remainder of the week, little has changed. Temperatures are forecast to see a warming trend through the remainder of the week, but temperatures may remain cool enough to support some combination of frost or freeze headlines for Wednesday morning. A series of weak shortwaves Wednesday through Friday may support light showers across higher elevations, but the overall trend supported by ensembles is for drier conditions. We are looking at temperatures potentially reaching the lower 80s in many areas by the weekend as high pressure shifts east into Idaho.

AVIATION /00Z TAFS THROUGH 00Z TUESDAY/

Issued at 535 PM MDT Sun May 17 2026

VFR conditions are expected at most sites through the period. DIJ is the one exception where CIGs/VIS have been borderline MVFR/VFR so far. Borderline MVFR/VFR conditions are expected to continue for DIJ. Conditions are forecast to remain dry at BYI, PIH, and IDA with VCSH remaining in the forecast for SUN and DIJ. Confidence is highest at DIJ with light showers now. Any showers at DIJ are expected to turn to snow after around 5z, which would bring a better chance of MVFR CIGS/VIS. Northerly winds behind the cold front will also increase tonight with gusts around 20-25 kts at DIJ, SUN, and BYI and closer to 35 kts at PIH and IDA. Winds will drop off by around 10kts after around 9 to 12z before ramping back again by late morning/early afternoon. Winds look to start dropping off gradually overall by around 20 to 21z for all TAF sites. Expect mostly clear skies by early to mid afternoon for all TAF sites.

PIH WATCHES/WARNINGS/ADVISORIES

Freeze Warning from 3 AM to 9 AM MDT Monday for IDZ051-052. Frost Advisory from 3 AM to 9 AM MDT Monday for IDZ053>055.