FXUS65 KPIH 191935
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
135 PM MDT Tue May 19 2026

.KEY MESSAGES...

- Frost and freeze conditions continue again into Wednesday
  morning.

- Gradual warming trend is underway this week.

- Best chance for showers and thunderstorms Wednesday and
  Thursday afternoons.


&&

.DISCUSSION...
Issued at 134 PM MDT Tue May 19 2026

General "troughiness" remains over eastern Idaho today, continuing 
our mildly unsettled pattern. Any precipitation chances today and 
fairly limited to the higher elevations farther north. Afternoon 
wind gusts will fall into the 20-25 mph range for most. Light winds 
and partly cloud conditions overnight will keep us a few degrees 
warmer than this morning was, so have gone with a FREEZE WARNING for 
the Mud Lake/Arco Desert zone where temperatures will be between 29 
and 32 degrees and FROST ADVISORY for the rest of our Snake River 
Plain zones where temperatures will be between 33 and 37 degrees. 
After Wednesday morning, we might get a break from frost/freeze 
products on Thursday morning, though the Mud Lake/Arco Desert zone 
will be close once again. One shortwave moves out of the area on 
Wednesday for a low to drop south of out Canada and into northern 
Montana late Wednesday into Thursday. The troughing associated with 
that low will impact us late Wednesday into Thursday, bringing an 
increasing chance for showers and thunderstorms, particularly in the 
Central Mountains, Eastern Highlands, and upper Snake River Plain. 
Precipiation will spread southeast through Wednesday night and any 
Thursday activity would be in the Eastern and Southeastern 
Highlands. This overnight movement of moisture will bring some light 
snow to the mountain tops, but impacts to travel is not expected. 

By Thursday, winds will swing around to be out of the north and cool 
us off a few degrees from the mid and upper 60s on Wednesday to the 
low and mid 60s on Thursday. Given the northerly winds, we may need 
a LAKE WIND ADVISORY, too, but it is borderline. By Friday morning, 
temperatures will be chilly again, ranging from the low 30s to low 
40s for most. But drier conditions are back by Friday morning, too, 
and will stay mostly dry through the holiday weekend with 
temperatures climbing into the mid 70s to low 80s by Saturday and 
more 80s on Sunday and Memorial Day.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1157 AM MDT Tue May 19 2026

VFR conditions expected through the period. Winds remain light
currently but should shift to the SW/W to everywhere outside of
KSUN to around 10 knots through early evening. Winds lessen
overnight becoming more southerly with a return to the SW/W
expected Wednesday afternoon. Not expecting any impactful precip
for eastern Idaho terminals.

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Frost Advisory from 3 AM to 9 AM MDT Wednesday for IDZ051-
053>055.
Freeze Warning from 3 AM to 9 AM MDT Wednesday for IDZ052.

&&

$$

DISCUSSION...AMM
AVIATION...McKaughan