textproduct: Pocatello

KEY MESSAGES

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

- Below-normal temperatures today spanning the 40s and 50s for most of the area before 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 237 AM MDT Sun May 17 2026

A Freeze Warning remains in effect through 9 AM for overnight lows ranging 27 to 32 degrees with a hard freeze possible across the Arco Desert/Mud Lake region. Daytime temperatures today will see another 5 to 10 degree drop from yesterday with highs spanning the 50s in the lower elevations and 30s and 40s in the mountainous terrain. Winds will begin to increase later this afternoon, necessitating a Lake Wind Advisory for American Falls Reservoir beginning at 3 PM and continuing through 9 PM this evening for north to northeast winds ranging 10 to 15 mph with gusts to around 25 mph. We may need to supplement an overnight Wind Advisory for elevated northeast winds pushing advisory level currently.

With the exception of some very light showers in the Island Park region today, the period of most organized precipitation will finally arrive late tonight as the center of low pressure rotates southeastward and showers begin across the southeast highlands. Temperatures will support snow with several inches forecast late Sunday and throughout Monday across the Bear River Range and highlands further east. Considering the overnight temperature forecast has increased slightly as compared to previous model runs, light accumulations will remain above 6,500 feet and therefore accumulations are no longer forecast across the highlands south of the Snake River Plain.

Low temperatures on Monday and Tuesday mornings will continue to require frost/freeze headlines for our growing zones, although temperature will begin to warm slightly further west by Tuesday morning as the system continues shifting eastward. By Wednesday night/Thursday morning, temperatures begin to remain above freezing as we warm back into above-normal territory for our daytime temperatures during the second half of next week. The National Blend maintains highs warming into the mid-80s across the eastern Magic Valley and portions of the Snake River Plain next weekend. Model consensus appears to be increasing in the long-term as indicated by the latest 500mb ensemble clusters, with high pressure favored through the end of next week.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 551 AM MDT Sun May 17 2026

Post-frontal northerly winds will increase heading into the evening and overnight hours, with gusts ranging 20 to 30 kts at the terminals. Winds will diminish Monday afternoon. While CIGs are forecast to remain VFR, KDIJ could see periods of high-end MVFR. Have included VCSH at KSUN this afternoon and persistent VCSH at KDIJ this afternoon through Monday morning. Probability of thunder is less than 10 percent at all sites throughout the period.

PIH WATCHES/WARNINGS/ADVISORIES

Freeze Warning until 9 AM MDT this morning for IDZ051>055.