Weather
Climate Avg| Time | Temp | Dew Pt | Humidity | Wind | Conditions |
|---|---|---|---|---|---|
| Start | 58.9 – 58.9°F | 55° OK | 85 – 85% | 5 mph NE | Clear sky |
| 8:00 AM | 62.5 – 62.5°F | 59° OK | 88 – 88% | 3 mph E | Partly cloudy |
| 9:00 AM | 64.5 – 64.5°F | 60° Sticky | 85 – 85% | 4 mph E | Partly cloudy |
| 10:00 AM | 61.5 – 61.5°F | 54° Nice | 75 – 75% | 5 mph SW | Partly cloudy |
| 11:00 AM | 63.7 – 63.7°F | 52° Nice | 66 – 66% | 6 mph SW | Partly cloudy |
| Finish | 65.4 – 65.4°F | 51° Nice | 59 – 59% | 6 mph SW | Partly cloudy |
Based on 3-year average for this date. Real forecast available in 322 days.
Elevation Profile
Course Stats
Mile Splits
| Mile | Grade |
|---|---|
| 1 | -0.2% |
| 2 | -0.5% |
| 3 | -0.6% |
| 4 | -0.1% |
| 5 | -0.3% |
| 6 | +0.1% |
| 7 | -0.1% |
| 8 | +0.5% |
| 9 | +0.2% |
| 10 | -1.0% |
| 11 | +0.6% |
| 12 | -0.2% |
| 13 | -0.2% |
| 14 | +0.1% |
| 15 | +0.1% |
| 16 | -0.1% |
| 17 | +0.1% |
| 18 | +0.4% |
| 19 | -0.4% |
| 20 | +0.5% |
| 21 | +0.5% |
| 22 | -0.5% |
| 23 | +0.1% |
| 24 | -0.1% |
| 25 | -0.5% |
| 26 | -0.4% |
| 27 | -0.3% |
RM Difficulty Index
Race-Day Weather History
Race-morning conditions on this date over the past 5 years: median 60°F with a 55°F dew point and 7 mph wind. 3 of 5 years were warm enough to slow race pace.
| Year | Temp | Dew Pt | Wind | Rain | Sky |
|---|---|---|---|---|---|
| 2025 | 60°F | 56°F | 6 mph | — | Partly cloudy |
| 2024 | 63°F | 58°F | 11 mph | — | Partly cloudy |
| 2023 | 58°F | 55°F | 10 mph | — | Drizzle |
| 2020 | 65°F | 55°F | 7 mph | — | Partly cloudy |
| 2017 | 60°F | 51°F | 7 mph | — | Drizzle |
Morning conditions (race window) on the Grandma's Marathon calendar date each year, from the ERA5 reanalysis archive — the race’s usual slot, not necessarily each edition’s exact day.
Grandma's Marathon Pace Calculator & Race Plan
Grandma's Marathon runs along the North Shore of Lake Superior from Two Harbors to Duluth. It's a fast, net-downhill course that draws a lot of BQ chasers. The scenery is beautiful and the June weather is usually cooperative, though Lake Superior can create its own microclimate.
The course has gentle rolling hills in the first half before flattening out for the run into Duluth. It's a course that rewards patience. Our splits give you a plan that holds back slightly in the rolling early miles.
Grandma's Marathon FAQ
When is the next Grandma's Marathon?›
The next Grandma's Marathon is on Saturday, June 19, 2027.
How long is the Grandma's Marathon?›
The Grandma's Marathon is 26.2 miles (42.195 km), the standard marathon distance. It runs in Two Harbors to Duluth, MN.
How much elevation gain does the Grandma's Marathon have?›
The Grandma's Marathon has about 299 ft (91 m) of climbing and 416 ft of descent, with a maximum grade of 1.04%.
Is the Grandma's Marathon flat, downhill, or hilly?›
The Grandma's Marathon is a net downhill course, dropping 118 ft (36 m) from start to finish, with 299 ft of climbing along the way.
How hard is the Grandma's Marathon?›
Runner's Math scores the Grandma's Marathon 28/100 (Moderate) — #30 of 38 marathon courses in our library, ranked by modeled time cost. The profile costs about 0:15 versus a flat course for a runner at 4:00-marathon pace.
What's the weather usually like at the Grandma's Marathon?›
Over the past 5 years on this date, median race-morning conditions were 60°F with a 55°F dew point and 7 mph wind. 3 of 5 years were warm enough to slow race pace.