Weather

Rain showers at Canoe Warehouse

NPS Photo / Mike Plummer-Steen

 

• Weather conditions change frequently, due to the site’s location on the north shore of Lake Superior. Cool onshore lake breezes are common in spring, summer and fall along with an occasional shower. Summer inland temperatures can reach into the 80’s and 90’s but are usually 10 to 15 degrees cooler by Lake Superior. The Heritage Center and Historic Site overlook Grand Portage Bay on Lake Superior and can be cool throughout the summer months. Having layers of clothing to put on or remove and being prepared for summer showers are the best advice we can offer to prepare you for the varieties of possible weather conditions. Winter weather can be very cold and windy, with consecutive days of sub-zero temperatures, followed by pleasant, calm, sunny and moderate temperatures in the 20’s and 30’s.
• Grand Portage, Minnesota Weather Facts
• • July is the average warmest month.
  • The highest recorded temperature was 95°F in 1995.
  • On average, the coolest month is January.
  • The lowest recorded temperature was -43°F in 1996.
  • The maximum average precipitation occurs in September.
• Mosquitoes, gnats, black flies are plentiful during the spring and summer months especially inland along the 8 ½ mile Grand Portage footpath. Layers of impenetrable clothing are recommended, as is the use of a head net. Also effective is the use of insect repellent containing DEET placed directly on outer clothing layers. The voyageur’s choice of repellent, bear grease and skunk oil, will probably discourage the swarms as well as your neighbors for a little while!

Weather Links:

NOAA

Thunder Bay Environment Canada

Monthly Weather Data for Grand Portage, Minnesota

Month	Average Highs (F)	Average Lows (F)	Rainfall Average (IN)
January	19	-3	1.33
February	24	2	0.80
March	35	14	1.55
April	47	27	2.22
May	61	38	2.86
June	69	46	3.19
July	75	51	3.45
August	73	52	3.10
September	64	43	3.68
October	52	34	3.25
November	37	20	2.37
December	24	4	1.56