Hagerman, Idaho Weather Forecast Discussion

378
FXUS65 KBOI 181538
AFDBOI
Area Forecast Discussion
National Weather Service Boise ID
938 AM MDT Thu Sep 18 2025
.DISCUSSION...An upper level ridge remains over the area today
with warm conditions and temperatures around 5-10 degrees above
normal. A low pressure system over southern CA will slowly move
northward into the Great Basin later today. High level clouds
will stream northward into southeast OR and southwest ID later
this afternoon, with mostly cloudy skies into Saturday and
Sunday. Isolated thunderstorms along the NV border on Saturday
afternoon as the system moves eastward from a trough moving
into the Pacific NW. Gusty outflow winds up to 50 mph possible
Saturday afternoon near the storms. No updates.
&&
.AVIATION...VFR. Increasing high clouds. Surface winds: variable
5-10kt becoming E-SE 5-15kt during the afternoon. Winds aloft
at 10kft MSL: variable 5-15kt.
KBOI...SE 5-10kt, except NW 5-10kt during the afternoon.
Weekend Outlook...Isolated showers and thunderstorms on
Saturday afternoon into Sunday. Gusty outflow winds up to 45kt
possible. Breezy west-northwest winds on Sunday afternoon behind
cold front.
&&
.PREV DISCUSSION...
SHORT TERM...Today through Saturday night...Sunny and warm
again today under persistent upper level high pressure.
Moisture in southern California, with remnants of former
tropical storm Mario, will surge northward today with a weak
upper low, and rapidly increase middle and high clouds in our
CWA tonight. Low levels will stay dry and no rain is expected
in our CWA through Friday night, but the clouds will limit
nighttime cooling and daytime warming from previous forecasts.
On Saturday the dissipating upper low will generate a 10-20
percent chance of showers and thunderstorms near the NV border,
drying Saturday night. Smoke from wildfires will stay mainly
aloft with little if any smoke near the surface.
LONG TERM...Sunday through Thursday...Saturday night`s clouds
will be swept east on Sunday by a stronger Gulf of Alaska upper
trough coming inland across the nw states. This trough will
push a surface cold front across our CWA, with a 20-30 percent
chance of showers and thunderstorms in our northern CWA
mountains, and gusty west/northwest winds over southern parts of
our CWA. Then clearing and cooling Sunday night through Monday
as the cold front and upper trough move rapidly east. Sunny and
warmer Tuesday under a new upper ridge behind the departing
trough. Another upper low is forecast in from southern
California Wednesday but models differ widely on the track of
that low. For now we`re forecasting a 10-20 percent chance of
showers and thunderstorms in all areas Wednesday, with
temperatures as warm as Tuesday.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...None.
OR...None.
&&
$$
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DISCUSSION...KA
AVIATION.....KA
SHORT TERM...LC
LONG TERM....LC

NWS BOI Office Area Forecast Discussion