Great Falls · first 14 days — live forecast · rest of month — climate corridor
🗺️ 14-day forecast map
Great Falls & neighbors — hit play
Every city on the map carries real forecast data from the same models as its city page, refreshed several times a day. The icon is the day's overall look; the number is the afternoon high.
Next 14 days at a glance
from the model forecast
Hottest day
102°
Thu, Sep 3
Coldest night
65°
Tue, Aug 25
Days with precip
9 / 14
of 14 forecast days
Nicest day
Tue, Aug 25
mild, dry, light wind
The next 4 weekends
plan ahead
Sat 29 – Sun 30 Aug
91° 69°
89% precip chance
Sat 5 – Sun 6 Sep
94° 71°
91% precip chance
Sat 12 – Sun 13 Sep
85° 65°
typical range
Sat 19 – Sun 20 Sep
84° 67°
typical range
30 days — Great Falls
14 forecast + 16 climatology
Tue · Today Sunny
93°65°5%⌄
Wind7 mph NE
Gusts22 mph
UV index9 – Very high
Precip chance5%
Sunrise06:51
Sunset19:59
Wed · Tomorrow Showers
93°72°7.4 mm⌄
Wind7 mph SE
Gusts16 mph
UV index9 – Very high
Precip chance73%
Sunrise06:52
Sunset19:58
Thursday 27/8 Showers
83°70°11.1 mm⌄
Wind8 mph SW
Gusts15 mph
UV index6 – High
Precip chance92%
Sunrise06:53
Sunset19:57
Friday 28/8 Mostly cloudy
80°69°14.0 mm⌄
Wind11 mph SW
Gusts21 mph
UV index6 – High
Precip chance91%
Sunrise06:53
Sunset19:55
Saturday 29/8 Mostly cloudy
80°69°9.1 mm⌄
Wind5 mph NW
Gusts14 mph
UV index6 – High
Precip chance89%
Sunrise06:54
Sunset19:54
Sunday 30/8 Showers
91°71°2.2 mm⌄
Wind7 mph SE
Gusts14 mph
UV index8 – Very high
Precip chance67%
Sunrise06:55
Sunset19:53
Monday 31/8 Sunny
94°74°0.1 mm⌄
Wind5 mph S
Gusts12 mph
UV index8 – Very high
Precip chance17%
Sunrise06:56
Sunset19:51
Tuesday 1/9 Sunny
96°76°3%⌄
Wind5 mph W
Gusts6 mph
UV index9 – Very high
Precip chance3%
Sunrise06:56
Sunset19:50
Wednesday 2/9 Sunny
100°79°2%⌄
Wind6 mph SW
Gusts13 mph
UV index9 – Very high
Precip chance2%
Sunrise06:57
Sunset19:49
Thursday 3/9 Sunny
102°80°2.4 mm⌄
Wind8 mph S
Gusts18 mph
UV index9 – Very high
Precip chance57%
Sunrise06:58
Sunset19:47
Friday 4/9 Sunny
101°78°6.6 mm⌄
Wind12 mph SE
Gusts24 mph
UV index9 – Very high
Precip chance59%
Sunrise06:58
Sunset19:46
Saturday 5/9 Mostly cloudy
94°75°6.5 mm⌄
Wind7 mph W
Gusts19 mph
UV index7 – High
Precip chance78%
Sunrise06:59
Sunset19:44
Sunday 6/9 Showers
80°71°16.7 mm⌄
Wind8 mph NE
Gusts17 mph
UV index6 – High
Precip chance91%
Sunrise07:00
Sunset19:43
Monday 7/9 Showers
83°70°0.6 mm⌄
Wind8 mph NE
Gusts17 mph
UV index6 – High
Precip chance53%
Sunrise07:01
Sunset19:42
Tuesday 8/9 Rain (climatological)
84°68°18.9 mm⌄
Day≈79–89°
Night≈62–73°
Precip≈6.6 in / September
(climatological)Typical range for these dates · 1991–2020
Wednesday 9/9 Partly cloudy (climatological)
89°71°20%⌄
Day≈84–95°
Night≈65–76°
Precip≈6.6 in / September
(climatological)Typical range for these dates · 1991–2020
Thursday 10/9 Partly cloudy (climatological)
92°72°20%⌄
Day≈87–97°
Night≈67–78°
Precip≈6.6 in / September
(climatological)Typical range for these dates · 1991–2020
Friday 11/9 Rain (climatological)
86°69°9.5 mm⌄
Day≈81–92°
Night≈64–74°
Precip≈6.6 in / September
(climatological)Typical range for these dates · 1991–2020
Saturday 12/9 Partly cloudy (climatological)
85°68°20%⌄
Day≈80–91°
Night≈63–74°
Precip≈6.6 in / September
(climatological)Typical range for these dates · 1991–2020
Sunday 13/9 Partly cloudy (climatological)
80°65°20%⌄
Day≈74–85°
Night≈60–71°
Precip≈6.6 in / September
(climatological)Typical range for these dates · 1991–2020
Monday 14/9 Rain (climatological)
81°66°11.7 mm⌄
Day≈75–86°
Night≈60–71°
Precip≈6.6 in / September
(climatological)Typical range for these dates · 1991–2020
Tuesday 15/9 Partly cloudy (climatological)
83°67°20%⌄
Day≈78–88°
Night≈62–72°
Precip≈6.6 in / September
(climatological)Typical range for these dates · 1991–2020
Wednesday 16/9 Partly cloudy (climatological)
88°70°20%⌄
Day≈82–93°
Night≈64–75°
Precip≈6.6 in / September
(climatological)Typical range for these dates · 1991–2020
Thursday 17/9 Rain (climatological)
91°72°20.0 mm⌄
Day≈86–96°
Night≈66–77°
Precip≈6.6 in / September
(climatological)Typical range for these dates · 1991–2020
Friday 18/9 Partly cloudy (climatological)
89°70°20%⌄
Day≈83–94°
Night≈65–76°
Precip≈6.6 in / September
(climatological)Typical range for these dates · 1991–2020
Saturday 19/9 Partly cloudy (climatological)
84°68°20%⌄
Day≈79–90°
Night≈62–73°
Precip≈6.6 in / September
(climatological)Typical range for these dates · 1991–2020
Sunday 20/9 Rain (climatological)
84°67°15.6 mm⌄
Day≈78–89°
Night≈62–73°
Precip≈6.6 in / September
(climatological)Typical range for these dates · 1991–2020
Monday 21/9 Partly cloudy (climatological)
85°68°20%⌄
Day≈79–90°
Night≈63–73°
Precip≈6.6 in / September
(climatological)Typical range for these dates · 1991–2020
Tuesday 22/9 Partly cloudy (climatological)
86°69°20%⌄
Day≈81–91°
Night≈63–74°
Precip≈6.6 in / September
(climatological)Typical range for these dates · 1991–2020
Wednesday 23/9 Rain (climatological)
91°71°18.4 mm⌄
Day≈85–96°
Night≈66–77°
Precip≈6.6 in / September
(climatological)Typical range for these dates · 1991–2020
How does a 30-day outlook work?
The first 14 days are a live model forecast. The back half of the month shows the typical range for those dates — useful for planning, not a literal prediction.
First 14 days: a real forecast, blended from NBM, ECMWF and GFS runs. Trust it most inside three days; by the second week treat it as a lean, not a promise.
Rest of the month: past day 14 we stop pretending to forecast and switch to the climate corridor — the range those dates have produced over three decades computed directly for Great Falls, with mild week-to-week wiggle.
Good question for this page: "Is late August usually humid in Chicago?" Bad question: "Do I need an umbrella on the 29th?" — three weeks out no one knows, and that's the honest answer.