Weather Almanac: Grand Portage, MN 55605

🗓️ Historical norms for September 2026

September avg. precipitation
🌧️ 3.49"
September days below freezing
📉 ≈1.9 days
Average September lows 41°F – 46°F
USDA Zone
4b
Annual extreme lows -25°F to -20°F
Last Spring Frost (36°F)
🌷 Always
First Fall Frost (36°F)
🍂 Always
Tue. September 1  

🌅 6:17 a.m.

H: 63°F – 76°F

L: 42°F – 54°F

🌇 7:39 p.m.

Wed. September 2  

🌅 6:18 a.m.

H: 63°F – 76°F

L: 42°F – 54°F

🌇 7:37 p.m.

Thu. September 3  

🌅 6:19 a.m.

H: 63°F – 76°F

L: 41°F – 54°F

🌇 7:35 p.m.

Fri. September 4  

🌅 6:21 a.m.

H: 62°F – 75°F

L: 41°F – 53°F

🌇 7:33 p.m.

Sat. September 5  

🌅 6:22 a.m.

H: 62°F – 75°F

L: 40°F – 53°F

🌇 7:31 p.m.

Sun. September 6  

🌅 6:24 a.m.

H: 61°F – 75°F

L: 40°F – 53°F

🌇 7:29 p.m.

Mon. September 7 Labor Day  

🌅 6:25 a.m.

H: 61°F – 74°F

L: 40°F – 53°F

🌇 7:27 p.m.

Tue. September 8  

🌅 6:26 a.m.

H: 61°F – 74°F

L: 39°F – 52°F

🌇 7:25 p.m.

Wed. September 9  

🌅 6:28 a.m.

H: 61°F – 74°F

L: 39°F – 52°F

🌇 7:23 p.m.

Thu. September 10  

🌅 6:29 a.m.

H: 60°F – 73°F

L: 39°F – 52°F

🌇 7:21 p.m.

Fri. September 11  

🌅 6:30 a.m.

H: 60°F – 73°F

L: 38°F – 51°F

🌇 7:19 p.m.

Sat. September 12  

🌅 6:32 a.m.

H: 59°F – 72°F

L: 38°F – 51°F

🌇 7:17 p.m.

Sun. September 13  

🌅 6:33 a.m.

H: 59°F – 72°F

L: 38°F – 51°F

🌇 7:15 p.m.

Mon. September 14 Holy Cross  

🌅 6:34 a.m.

H: 59°F – 72°F

L: 37°F – 50°F

🌇 7:13 p.m.

Tue. September 15  

🌅 6:36 a.m.

H: 58°F – 71°F

L: 37°F – 50°F

🌇 7:11 p.m.

Wed. September 16  

🌅 6:37 a.m.

H: 58°F – 71°F

L: 36°F – 50°F

🌇 7:08 p.m.

Thu. September 17  

🌅 6:39 a.m.

H: 57°F – 71°F

L: 36°F – 49°F

🌇 7:06 p.m.

Fri. September 18  

🌅 6:40 a.m.

H: 57°F – 70°F

L: 36°F – 49°F

🌇 7:04 p.m.

Sat. September 19  

🌅 6:41 a.m.

H: 57°F – 70°F

L: 35°F – 49°F

🌇 7:02 p.m.

Sun. September 20  

🌅 6:43 a.m.

H: 56°F – 69°F

L: 35°F – 48°F

🌇 7:00 p.m.

Mon. September 21  

🌅 6:44 a.m.

H: 56°F – 69°F

L: 34°F – 48°F

🌇 6:58 p.m.

Tue. September 22 Autumn Equinox  

🌅 6:45 a.m.

H: 55°F – 69°F

L: 34°F – 48°F

🌇 6:56 p.m.

Wed. September 23  

🌅 6:47 a.m.

H: 55°F – 68°F

L: 34°F – 47°F

🌇 6:54 p.m.

Thu. September 24  

🌅 6:48 a.m.

H: 54°F – 68°F

L: 33°F – 47°F

🌇 6:52 p.m.

Fri. September 25  

🌅 6:50 a.m.

H: 54°F – 68°F

L: 33°F – 47°F

🌇 6:50 p.m.

Sat. September 26 🌕

🌅 6:51 a.m.

H: 54°F – 67°F

L: 33°F – 46°F

🌇 6:48 p.m.

Sun. September 27  

🌅 6:52 a.m.

H: 53°F – 67°F

L: 32°F – 46°F

🌇 6:46 p.m.

Mon. September 28  

🌅 6:54 a.m.

H: 53°F – 66°F

L: 32°F – 46°F

🌇 6:44 p.m.

Tue. September 29  

🌅 6:55 a.m.

H: 52°F – 66°F

L: 31°F – 45°F

🌇 6:42 p.m.

Wed. September 30  

🌅 6:56 a.m.

H: 52°F – 66°F

L: 31°F – 45°F

🌇 6:40 p.m.


Temperature climatic data from weather station: GRAND PORTAGE (USC00213296)

Precipitation climatic data from weather station: GRAND PORTAGE (USC00213296)

Agricultural climatic data from weather station: GRAND PORTAGE (USC00213296)