Whitefish weather in September

In September, Whitefish sees average daytime highs of 65°F and overnight lows near 41°F, with 1.9 in of precipitation across 7.3 wet days and about 12.4 hours of daylight. It is the 4th-warmest and 10th-wettest month of the year here.

Highs ease over the month, from about 71°F in the first days to 59°F by the end. The sky is clear or mostly clear about 41% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 h 12 min at the start of September to 11 h 30 min by month's end. Set against the rest of the year, September is Whitefish's 3rd-clearest and 7th-windiest month. For the whole year in context, see Whitefish's year-round climate.

Daytime high
65°
4th warmest
Overnight low
41°
9th coldest
Precipitation
1.9 in
7.3 wet days
Daylight
12 h 18 min
6:21 AM – 6:42 PM
Cloud cover
48%
3rd clearest
Wind
4 mph
7th windiest
Solar energy
4.36 kWh/m²
Travel score
6.3
out of 10

Whitefish is city in Flathead County, Montana, United States.

Density
229/km²
people per km²

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 71°F in the first days to 59°F by the end.

A typical September day in Whitefish reaches about 65°F in the afternoon and slips back to 41°F overnight — a 24°F spread between the day's warmth and the night's chill. On most days the high lands between 52°F and 78°F. Set against its neighbours, September runs about 11°F cooler than August and about 16°F warmer than October.

20°40°60°80°151015202530
Avg high (°F)Avg low (°F)
17145
27145
37145
47044
57044
66944
76944
86843
96843
106743
116742
126742
136642
146642
156542
166541
176441
186441
196440
206340
216340
226239
236239
246139
256138
266038
276038
285937
295837
305837

How September really feels in Whitefish

Once humidity and wind are folded in, September averages 0 days that feel above 90°F and 0 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
0
wind chill below the day's low

September sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Whitefish weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 10th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan28° / 15°3.114.916.58.60.0
Feb31° / 15°2.512.413.49.90.0
Mar38° / 21°3.114.912.511.60.0
Apr48° / 28°2.813.76.913.41.6
May58° / 36°3.3142.1154.0
Jun66° / 43°3.8130.615.85.5
Jul76° / 49°1.15.6015.57.9
Aug76° / 48°1.15.4014.17.9
Sep65° / 41°1.97.30.312.46.3
Oct49° / 32°2.912.43.710.62.0
Nov36° / 23°3.514.912.690.0
Dec27° / 15°3.11415.98.20.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 41% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 17% of September, with mostly cloudy or overcast conditions the remaining 42%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
16337
26337
36238
46238
56139
66238
76139
86040
96040
105941
115842
125842
135842
145842
155743
165743
175743
185743
195743
205743
215743
225743
235743
245743
255644
265644
275644
285644
295545
305446

Chance of precipitation in September

Any precipitationSnow

Whitefish gets around 1.9 in of rain and snow over 7.3 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 25% and peaks near 28% on the wettest days, and about 0 day brings snow. The odds climb toward the end of the month.

0%10%20%30%40%151015202530
Rain chance (%)Snow chance (%)
1190
2200
3210
4210
5220
6220
7230
8230
9240
10241
11251
12251
13251
14261
15251
16251
17251
18251
19251
20251
21251
22261
23262
24262
25272
26273
27273
28273
29284
30284

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

Most of September feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, September lands in the dry band about 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)
1991
2991
3991
4991
5991
6991
7991
8991
9991
10991
11991
121000
131000
141000
151000
161000
171000
181000
191000
201000
211000
221000
231000
241000
251000
261000
271000
281000
291000
301000

Wind in September

Winds average 4 mph in September.

Across September, daily wind ranges from about 4 mph on the calmest days to 4 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (mph)Feels
14calm
24calm
34calm
44calm
54calm
64calm
74calm
84calm
94calm
104calm
114calm
124calm
134calm
144calm
154calm
164calm
174calm
184calm
194calm
204calm
214calm
224calm
234calm
244calm
254calm
264calm
274calm
284calm
294calm
304calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 h 12 min at the start of September to 11 h 30 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 102 minutes over September. Sunrise moves from 6:00 AM to 6:42 AM, and sunset from 7:14 PM to 6:12 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.26:007:14
213.26:017:12
313.16:037:10
413.16:047:08
513.06:057:06
612.96:077:04
712.96:087:02
812.86:107:00
912.86:116:57
1012.76:136:55
1112.66:146:53
1212.66:156:51
1312.56:176:49
1412.56:186:46
1512.46:206:44
1612.36:216:42
1712.36:236:40
1812.26:246:38
1912.26:266:36
2012.16:276:33
2112.06:286:31
2212.06:306:29
2311.96:316:27
2411.96:336:25
2511.86:346:22
2611.76:366:20
2711.76:376:18
2811.66:396:16
2911.66:406:14
3011.56:426:12

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.36 kWh/m².

For context, solar energy here swings from a low near 0.99 kWh/m² to a high of 7.24 kWh/m² in July across the year — September's 4.36 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.3Bright
25.2Bright
35.1Bright
45.1Bright
55.0Bright
64.9Bright
74.9Bright
84.8Bright
94.7Bright
104.7Bright
114.6Bright
124.5Bright
134.5Bright
144.4Bright
154.4Bright
164.3Bright
174.2Bright
184.2Bright
194.1Bright
204.1Bright
214.0Bright
224.0Moderate
233.9Moderate
243.9Moderate
253.8Moderate
263.8Moderate
273.7Moderate
283.6Moderate
293.6Moderate
303.5Moderate
Planning a trip in September

Is September a good time to visit Whitefish?

Our two travel scores rate September for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

6.3
Sightseeing
3rd-best month of the year
2.5
Beach & pool
3rd-best month of the year

September is a reasonable time to visit Whitefish for sightseeing.

What to pack for Whitefish in September

From September's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In September, Whitefish sees daytime highs around 65°F and nights near 41°F. Worth packing: a warm layer. About 7 days see rain.

a warm layer

UV index in Whitefish in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 4 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Whitefish peaks around July 18 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 18 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJul 18UV 8Dec 18UV 1
UV index (midday)Level
Jan1Low
Feb2Low
Mar4Moderate
Apr5High
May7High
Jun6High
Jul8Very high
Aug7High
Sep4Moderate
Oct3Moderate
Nov1Low
Dec1Low

Air quality in Whitefish in September

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where September falls, not just the annual average.

Air quality in Whitefish is worst in September — around 50 µg/m³ PM2.5 (poor), about 14.6× the cleanest month (December, 3 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0204060JanFebMarAprMayJunJulAugSepOctNovDecGoodModeratePoorGoodSep 1049 µg/m³Dec 223 µg/m³
PM2.5 (µg/m³)Level
Jan4Good
Feb4Good
Mar6Good
Apr8Good
May10Good
Jun9Good
Jul13Moderate
Aug45Poor
Sep50Poor
Oct8Good
Nov6Good
Dec3Good
Location & terrain

Where is Whitefish?

Whitefish sits at 48.4°N, 114.3°W, 0 ft above sea level, in United States. The nearest listed city is Kalispell, 15 mi away.

Topography around Whitefish

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Whitefish.

Within 2 miles, the terrain around Whitefish has only modest variations in elevation — a maximum elevation change of 472 ft around an average of 3,081 ft above sea level; within 10 miles, very significant variations in elevation — a maximum elevation change of 4,216 ft; within 50 miles, extreme variations in elevation — a maximum elevation change of 8,248 ft.

The land around Whitefish is covered by trees (39%) and grassland (34%) within 2 miles, trees (68%) and grassland (20%) within 10 miles, and trees (75%) within 50 miles.

2 miles
472 ft
10 miles
4,216 ft
50 miles
8,248 ft
treesgrasslandcroplandartificial surfacesbare terrainwatermoss and lichen
September weather nearby: Kalispell 15 mi · Cranbrook 99 mi · Missoula 107 mi · Lethbridge 112 mi · Coeur d'Alene 124 mi · Post Falls 130 mi · Spokane Valley 144 mi · Opportunity 144 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Whitefish (48.4111°, -114.3376°, elevation 0 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).