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SunnyDays

ERA5 almanac — 8 years of real data

Boundary Waters in June

Boundary Waters in June: 39% of days see measurable rain, 74°F average high, 26% of days historically clear (n=240, ERA5 2018–2025).

Boundary Waters in June is historically a poor month for sun: only 26% of days clear across 8 years (n=240, avg high 74°F). July is the clearest month for Boundary Waters historically. Historical average, not a forecast.

What you are reading: 8-year historical averages from the ERA5 reanalysis, not a forecast. A month that is historically 90% clear can still be overcast on your specific trip. For this week’s actual forecast, see the live Boundary Waters page. Both can be true at once: “historically strong in this month; this particular week is not.” We label which is which.

Early vs. Late June

Clear-sky percentage for Boundary Waters in June, split by half-month. “n” is the number of days sampled across 8 years (2018–2025).
Period % Clear days Sample (n) Avg high
Early June
1st–15th		 25% n=120 74°F
Late June
16th–end		 28% n=120 74°F
Full month average 26% n=240 74°F

Sunshine & warmth in June

A second measure using actual sunshine hours (ERA5 sunshine_duration), not the daily weather code. A Lowcountry day with 12 hours of sun and a 25-minute afternoon storm is counted below as a warm, sunny day — because it was. How we define this.

Sunshine-based metrics for Boundary Waters in June. Primary: % of days ≥ 72°F with > 6 h of sunshine.
Period Warm & sunny (≥72°F, >6 h sun) Sample (n)
Early June
1st–15th		 49% n=120
Late June
16th–end		 68% n=120
Full month average 58% n=240
13.7 h median sunshine per day 83% of days exceed 8 h sunshine 39% of days see ≥ 1 mm rain — rain is not hidden
Comparison (old vs new): WMO-code “clear” bar: 26%. Sunshine-based “warm & sunny”: 58%. The 32-point gap is from brief afternoon convective storms that stamp the whole day as “rain” in the WMO code but leave the bulk of the sunshine untouched.

Bottom line

Boundary Waters is mostly overcast in June historically: only 26% of days are clear across 8 years (n=240), avg high 74°F. If you want sun in Boundary Waters, July is historically much better. Most visitors this month will see more clouds than sun.

→ See all destinations in July — historically the best month for sun in Boundary Waters.

Every month in Boundary Waters

Compare across all months with data. Numbers are historical clear-sky %.

Historical clear-sky % for Boundary Waters, all months, ERA5 2018–2025.
Month % Clear Sample (n)
January 0% n=248 All destinations →
February 0% n=226 All destinations →
March 0% n=248 All destinations →
April 0% n=240 All destinations →
May 10% n=248 All destinations →
June ← this page 26% n=240 All destinations →
July 31% n=248 All destinations →
August 30% n=248 All destinations →
September 20% n=240 All destinations →
October 2% n=248 All destinations →
November 0% n=240 All destinations →
December 0% n=248 All destinations →

Frequently asked

Does it rain in Boundary Waters in June?

Sometimes. Boundary Waters sees measurable rain on 39% of days in June historically (n=240 days, ERA5 2018–2025) — not frequent enough to plan around, but not negligible either.

Is Boundary Waters good for sun in June?

Not usually. Boundary Waters is historically overcast in June: only 26% of days are clear (avg high 74°F, n=240 days, ERA5 2018–2025). July is historically far better for sun here.

How Boundary Waters compares in June

Head-to-head clear-sky comparisons against destinations travelers plausibly weigh against Boundary Waters this month — same passport tier, similar flight distance, both sides from the same 8-year ERA5 record.

All percentages are historical averages from the ERA5 reanalysis via Open-Meteo, 8 full years (2018–2025). “Clear” means avg high ≥ 72 °F, precipitation < 1 mm, and a non-precipitation weather code. This is history, not a forecast. The live 7-day outlook for any destination is on its own page and may differ from the long-run average. Data from Open-Meteo.