International Falls weather in September: International Falls, Minnesota: normal highs, lows, rain and records for September
International Falls in September has a normal high of 66°F and a normal low of 42°F, a daily mean of 54°F, falling from 72°F on the 1st to 60°F by the 30th. Measurable precipitation falls on 12 days in a normal September, 3.00 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 19°C and low of 6°C, 76 mm of precipitation and 0 cm of snow in September.
- NOAA stationInternational Falls International Airport
- Station IDUSW00014918
- Location48.56°N 93.40°W
- Elevation1,183 ft (361 m)
- Population5,498
- Jan 16° -6°
- Feb 22° -3°
- Mar 35° 12°
- Apr 50° 26°
- May 64° 38°
- Jun 74° 48°
- Jul 78° 52°
- Aug 76° 50°
- Sep 66° 42°
- Oct 51° 31°
- Nov 34° 18°
- Dec 21° 3°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is International Falls in September?
The normal high is 66°F and the normal low 42°F, for a daily mean of 54.2°F. September is 8.6°F cooler than August and 13.1°F warmer than October. September is the 4th warmest month of the year in International Falls and the 4th wettest. Across the month the normal high falls 12°F, from 72°F on September 1 to 60°F on September 30. From one year to the next September's mean temperature typically moves about 2.9°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 51°F and 57°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 40%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 72°F | 47°F | 39% | 20% |
| September 8 | 70°F | 45°F | 39% | 20% |
| September 15 | 67°F | 42°F | 40% | 20% |
| September 22 | 64°F | 40°F | 40% | 20% |
| September 30 | 60°F | 37°F | 40% | 19% |
Every day of September: normal high, low and chance of precipitation (warmest afternoon September 1, coldest night September 30)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| September 1 | 72°F | 47°F | 39% | 20% | 13 h 30 min |
| September 2 | 72°F | 46°F | 39% | 20% | 13 h 30 min |
| September 3 | 72°F | 46°F | 39% | 20% | 13 h 20 min |
| September 4 | 71°F | 46°F | 39% | 20% | 13 h 20 min |
| September 5 | 71°F | 46°F | 39% | 20% | 13 h 20 min |
| September 6 | 71°F | 45°F | 39% | 20% | 13 h 10 min |
| September 7 | 70°F | 45°F | 39% | 20% | 13 h 10 min |
| September 8 | 70°F | 45°F | 39% | 20% | 13 h |
| September 9 | 69°F | 44°F | 39% | 20% | 13 h |
| September 10 | 69°F | 44°F | 40% | 20% | 13 h |
| September 11 | 69°F | 44°F | 40% | 20% | 12 h 50 min |
| September 12 | 68°F | 43°F | 40% | 20% | 12 h 50 min |
| September 13 | 68°F | 43°F | 40% | 20% | 12 h 50 min |
| September 14 | 67°F | 43°F | 40% | 20% | 12 h 40 min |
| September 15 | 67°F | 42°F | 40% | 20% | 12 h 40 min |
| September 16 | 66°F | 42°F | 40% | 20% | 12 h 40 min |
| September 17 | 66°F | 42°F | 40% | 20% | 12 h 30 min |
| September 18 | 66°F | 41°F | 40% | 20% | 12 h 30 min |
| September 19 | 65°F | 41°F | 40% | 20% | 12 h 30 min |
| September 20 | 65°F | 41°F | 40% | 20% | 12 h 20 min |
| September 21 | 64°F | 40°F | 40% | 20% | 12 h 20 min |
| September 22 | 64°F | 40°F | 40% | 20% | 12 h 20 min |
| September 23 | 63°F | 39°F | 40% | 20% | 12 h 10 min |
| September 24 | 63°F | 39°F | 40% | 20% | 12 h 10 min |
| September 25 | 62°F | 39°F | 40% | 20% | 12 h 10 min |
| September 26 | 62°F | 38°F | 40% | 20% | 12 h |
| September 27 | 61°F | 38°F | 40% | 20% | 12 h |
| September 28 | 61°F | 38°F | 40% | 19% | 11 h 50 min |
| September 29 | 60°F | 37°F | 40% | 19% | 11 h 50 min |
| September 30 | 60°F | 37°F | 40% | 19% | 11 h 50 min |
- Normal high
- 66°FSeptember average
- Normal low
- 42°FSeptember average
- Precipitation
- 3.00 inmonth total
- Days with precipitation
- 120.01 inch or more
- Snowfall
- 0.1 inmonth total
- Nights at 32°F or colder
- 5
- Daylight
- 13 h 30 min to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 12
- Days at 80°F or more
- 3
- Sunshine
- 71%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00014918; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain or snow in International Falls in September?
On a given September day the chance of 0.01 inch or more is 40% on average, highest around September 19 (40%). In all, 3.00 in falls on 12 days of a normal September, 1 of them with an inch or more.
In a normal September in International Falls, 5 nights fall to freezing and snowfall averages 0.1 inches.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00014918.
How humid and windy is International Falls in September?
At 3 p.m. the normal temperature is 57°F with 53% relative humidity and a dew point of 41°F; at 6 a.m. it is 41°F with 88% humidity. The wind averages 7.5 mph, most often from the west in the afternoon. A dew point under 50°F feels dry.
| Time | Temperature | Dew point | Humidity | Wind | Clear or few clouds |
|---|---|---|---|---|---|
| 6 a.m. | 41°F | 38°F | 88% | 6.1 mph | 48% |
| 9 a.m. | 49°F | 42°F | 76% | 8.9 mph | 45% |
| noon | 56°F | 41°F | 58% | 10.3 mph | 42% |
| 3 p.m. | 57°F | 41°F | 53% | 10.3 mph | 42% |
| 6 p.m. | 52°F | 41°F | 66% | 7.0 mph | 44% |
| 9 p.m. | 46°F | 40°F | 79% | 6.1 mph | 49% |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00014918. Hourly normals exist only for NOAA's first-order stations; a dash where NOAA publishes no value for that hour (the sky at some hours).
What are the records for September in International Falls?
The warmest September temperature on International Falls's official record (since 1897) is 96°F, on September 7, 1906; the coldest is 19°F, on September 15, 2011. The wettest September brought 7.36 in (1961); the snowiest, 2.0 inches (1912).
The September mean against the 1991-2020 normal of 54.2°F: 2021 59.0°F (+4.8), 2022 56.1°F (+1.9), 2023 59.2°F (+5.0), 2024 62.3°F (+8.1), 2025 58.1°F (+3.9), 2026 57.1°F (+2.9). 6 of 6 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 59.0°F | +4.8°F | 3.23 in |
| 2022 | 56.1°F | +1.9°F | 2.36 in |
| 2023 | 59.2°F | +5.0°F | 3.14 in |
| 2024 | 62.3°F | +8.1°F | 3.58 in |
| 2025 | 58.1°F | +3.9°F | 1.40 in |
| 2026 | 57.1°F | +2.9°F | 3.41 in |
Source: records: ACIS, NWS threaded record INLthr; recent months: ACIS, station USW00014918. Records and recent months use complete months only.
How does September in International Falls compare across Minnesota?
Across the 129 places PlainClimate covers in Minnesota, September normal highs run from 62°F in Lutsen to 76°F in Milan; International Falls's is 66°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.
Other months and places
- International Falls in August76°F by day, 50°F at night
- International Falls in October51°F by day, 31°F at night
- International Falls through the yearEvery month, frost dates, records and recent years
- Minnesota in SeptemberThe statewide normal and the warmest and coolest places
- Milan: Minnesota's warmest Septembernormal high 76°F