textproduct: Boise

LONG TERM...Tuesday through Saturday

Unsettled conditions prevail through the long term. Tuesday is looking to start out dry but with increasing high clouds as mid-level moisture makes its way around the ridge to our west. By late Tuesday/early Wednesday, the bulk of the moisture advection will be overhead allowing for increasing chances of precipitation chances of 20-70% across much of the area, generally increasing as you move from south to north. Snow levels start out at 2-3 kft MSL Tuesday night, so the Snake Plain could see a wintery mix early Wednesday morning before snow levels rise to 4-6kft MSL. Through the latter half of the week, there is good model consensus of the ridge moving over our area. The area will begin to dry out Thursday; however, A shortwave grazing our northern zones late Thursday/early Friday will keep elevated precipitation chances (20-50%) in Baker county, the west Central Mountains, and Boise mountains. That shortwave, and the system evolution following it, is helping mitigate air stagnation concerns despite general ridging over our area.

Friday into the weekend, Confidence is increasing in a trough digging down over our area. This trough is leading to elevated precipitation chances (50-70%) across the majority of our area Friday evening through Saturday. Uncertainty does, however, remain regarding just how deep the trough will get. This is resulting in some uncertainty with how much we will cool off over the weekend, and how just low the snow level drops. Temperatures begin near normal on Tuesday, increasing to 5-10 degrees above normal Thursday. Temperatures will begin to cool off through the weekend, but as noted earlier, uncertainty remains to what degree; for now, am maintaining temps near normal for Saturday.

AVIATION

Areas of IFR/MVFR continuing early this afternoon in Fog/Low stratus, continuing to improve to VFR. Fog/low stratus will increase again overnight in mtn valleys and lower Snake Plain, confidence decreasing from KBOI on east. resulting in IFR/LIFR conditions lasting through the morning. Surface Winds: S-E 5-15 kt, becoming variable overnight. Winds aloft at 10kft MSL: W-SW 5-20 kt.

KBOI...VFR conditions expected overnight. Although there is a slight chance (15%) of fog/low stratus developing at terminal between Sun/11z-Sun/17z. Confidence in development is low. Surface winds: SE 6-12 kt, decreasing to under 8 kt by Sun/00z.

AIR STAGNATION

Another round of stagnant air expected Sunday with mixing heights only 1500 to 2500 feet above ground level by mid afternoon. Improving conditions Monday as a trough of low pressure moves through the region and winds shift to the northwest.

BOI WATCHES/WARNINGS/ADVISORIES

ID...None. OR...None.