Payette, Idaho 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

815
FXUS65 KBOI 131552
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
952 AM MDT Sun Jul 13 2025

.DISCUSSION...Some minor updates made to the forecast this
morning. Based on observations from yesterday, and in
collaboration with neighboring offices, have opted to lower the
forecast relative humidities for today through tomorrow. With
minimum RHs for the day now forecasted to generally be between
10-15% for lower elevations and 20-30% across higher terrain. A
new (as of yesterday evening) wildfire start in central Oregon
is leading to more hazy skies this morning across southeastern
Oregon and eventually spreading to far Southern Idaho this
afternoon. Otherwise, aside from cumulus development over the
central Idaho mountains, clear skies are expected throughout
southwest Idaho. Aside from that, the current forecast looks to
be on track with temperatures climbing to around 100 degrees
throughout the lower elevations. Models continue to show Pacific
moisture making into central Oregon, but not quite making it
into Harney county. This should limit any isolated
shower/thunder development to central Oregon, with the chance of
anything making it into Harney county <15%. Mid-level clouds
will increase in southern Oregon this afternoon.



&&

.AVIATION...VFR. Localized smoke near wildfires. Fire in
Crook County, OR may produce smoke near KBNO. High density
altitude during afternoon hours due to hot temperatures.
Surface winds: NW 5-15 kt with gusts 15-25 kt this afternoon.
Winds aloft at 10kft MSL: NW 5- 15 kt.

KBOI...VFR. High density altitude during afternoon hours due to
hot temperatures. Surface winds: light and variable this
morning, becoming NW 7-12 kt with gusts to 20 kt this afternoon.


&&

.PREV DISCUSSION...
SHORT TERM...Today through Tuesday night...The next couple of
days are hot as our region remains on the northern edge of the
Desert SW heat dome. Sites in the Treasure Valley and lower
basins in SE Oregon could touch 100 degrees, with the Lower
Treasure Valley seeing highs of 100 to 104. The Heat Advisory
remains in place due to the combination of daytime heat and warm
overnight low temperatures providing limited relief. Elevated
moisture along the Sierra Crest yesterday, will expand into
s-central Oregon today increasing afternoon cloud cover and the
possibility of a shower or thunderstorm sneaking into southern
Harney County. The w-central Idaho mtns will also see cumulus
development this afternoon as a weak upper wave riding the ridge
tracks though the ID panhandle. Moisture increases along the
northern NV border on Monday, bringing a 10-15% chance of high-
based showers and thunderstorms. An upper trough entering the
Pac NW Monday afternoon will push a dry cold front through the
region Monday evening. While winds will already be NWly, speeds
will pick up across SE Oregon, with gusts of 25 to 35 mph
possible through the evening. The cold frontal passage returns
temperatures to around normal on Tuesday and keeps breezy
northwest winds in place. A slight chance of showers and
thunderstorms returns to s-central Idaho Tuesday afternoon,
otherwise the region remains dry. Any shower/storm development
through Tuesday will see little rain and locally gusty winds. A
new wildfire in e-central Oregon along with other
local/regional wildfires will continue to add smoke/haze to the
area.

LONG TERM...Wednesday through Sunday...Northwest flow aloft
will prevail on Wednesday, keeping temperatures near normal
with dry conditions. Ensembles generally indicate a ridge
rebuilding across the northern Great Basin on Thursday, then
persisting through Sunday. Models favor troughing to our north
through the period, keeping the center of the ridge and
associated hotter temperatures to our south. Temperatures are
expected to average around 5 degrees above normal Thursday
through Sunday under this pattern. Models continue to indicate
potential for monsoon moisture to rotate around the ridge into
our area, but potential at any given time and location remains
low (less than 15% chance). Therefore, left shower/thunderstorm
mention out of the forecast through the period. Expect breezy
afternoon winds under west to southwest flow aloft.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...Heat Advisory from noon today to 9 PM MDT Monday IDZ012.
OR...Heat Advisory from noon MDT /11 AM PDT/ today to 9 PM MDT /8
     PM PDT/ Monday ORZ064.

&&

$$

www.weather.gov/Boise

Interact with us via social media:
www.facebook.com/NWSBoise
www.x.com/NWSBoise

DISCUSSION...NF
AVIATION.....LC
SHORT TERM...DG
LONG TERM....ST