Minnesota weather and outdoor projects
Minnesota has cold winters and warm summers, with a short outdoor project season. The Twin Cities usually see their last spring freeze in late April or early May, while Duluth on Lake Superior stays cool much later into spring and has cooler summers.
June through early September is the best window for staining, painting and concrete. Spring can be wet, and fall cools quickly, with frosty nights by late September in the north. Concrete poured in the shoulder seasons often needs curing blankets. Freeze-thaw cycles and winter salt are hard on driveways and steps.
Frost dates in Minnesota
In Minneapolis–St. Paul, the median last spring freeze (32°F) is around April 23 and the median first fall freeze is around October 18, a frost-free season of about 176 days.
In Duluth, the median last spring freeze (32°F) is around May 13 and the median first fall freeze is around October 1, a frost-free season of about 140 days.
Frost dates matter for concrete, which must not freeze in its first 48 hours, for paint and caulk that need nights above their minimum, and for lawn care, since crabgrass preventer goes down as the soil warms in spring. See how late in fall you can stain, paint or seal.
Best time to stain a deck in Minnesota
In Minneapolis–St. Paul, the most reliable months are May–September. October can also work on the right days. November–March is too cold, with average highs around 33°F. In April, nights average about 38°F, too cold for the coating to dry and cure overnight. October is cool, with highs around 58°F, so choose the warmest afternoons.
In Duluth, the most reliable months are June–August. May and September can also work on the right days. October–April is too cold, with average highs around 35°F. In May and September, nights average about 44°F, so finish early on mild days and check the overnight low.
Check this week’s hour-by-hour verdict with the deck staining forecast.
Best time to paint outside in Minnesota
In Minneapolis–St. Paul, the most reliable months are May–September. April and October can also work on the right days. November–March is too cold, with average highs around 33°F. April is cool, with highs around 57°F, so choose the warmest afternoons. In October, nights average about 41°F, so finish early on mild days and check the overnight low.
In Duluth, the most reliable months are June–September. May and October can also work on the right days. November–April is too cold, with average highs around 32°F. In May, nights average about 41°F, so finish early on mild days and check the overnight low. October is cool, with highs around 53°F, so choose the warmest afternoons.
Check this week’s hour-by-hour verdict with the exterior painting forecast.
Best time to pour concrete in Minnesota
In Minneapolis–St. Paul, the most reliable months are May–September. October can also work on the right days. November–April averages about 23 nights a month at or below 32°F, so fresh concrete needs blankets or heated enclosures. October brings about 6 freezing nights a month, so pick a mild spell and keep curing blankets on hand.
In Duluth, the most reliable months are June–September. May can also work on the right days. October–April averages about 25 nights a month at or below 32°F, so fresh concrete needs blankets or heated enclosures. May brings about 4 freezing nights a month, so pick a mild spell and keep curing blankets on hand.
Check this week’s hour-by-hour verdict with the concrete pouring forecast.
Best time to seal a driveway in Minnesota
In Minneapolis–St. Paul, the most reliable months are June–September. May can also work on the right days. October–April is too cold, with average highs around 40°F. In May, nights average about 50°F, so finish early on mild days and check the overnight low.
In Duluth, the most reliable months are July–August. June and September can also work on the right days. October–April is too cold, with average highs around 35°F. In May, nights average about 41°F, too cold for the coating to dry and cure overnight. In June, nights average about 50°F, so finish early on mild days and check the overnight low. September is cool, with highs around 67°F, so choose the warmest afternoons.
Check this week’s hour-by-hour verdict with the driveway sealing forecast.
Best time to fertilize or treat a lawn in Minnesota
In Minneapolis–St. Paul, the most reliable months are May–September. April and October can also work on the right days. November–March is too cold, with average highs around 33°F. April and October are cool, with highs around 57°F, so choose the warmest afternoons.
In Duluth, the most reliable months are May–September. October can also work on the right days. November–April is too cold, with average highs around 32°F. October is cool, with highs around 53°F, so choose the warmest afternoons.
Check this week’s hour-by-hour verdict with the lawn fertilizer forecast.
How the weather differs across Minnesota
| Place | Hottest month avg high | Coldest month avg low | Rain per year | Last spring freeze | First fall freeze |
|---|---|---|---|---|---|
| Minneapolis–St. Paul | 83°F | 9°F | 32 in | April 23 | October 18 |
| Duluth | 78°F | 2°F | 31 in | May 13 | October 1 |
Of the places above, Minneapolis–St. Paul has the most good months for staining, painting and concrete combined (15 job-months), and Duluth has the fewest (11). If you live between them, expect something in between, and higher ground to be cooler with a shorter season.
Monthly weather in Minneapolis–St. Paul
| Month | Avg high | Avg low | Wet days* | Rain | 3 PM humidity | Freezing nights |
|---|---|---|---|---|---|---|
| January | 24°F | 9°F | 3 | 0.9 in | 65% | 31 |
| February | 29°F | 13°F | 3 | 0.9 in | 59% | 27 |
| March | 42°F | 25°F | 5 | 1.7 in | 51% | 24 |
| April | 57°F | 38°F | 6 | 2.9 in | 42% | 9 |
| May | 69°F | 50°F | 8 | 3.9 in | 44% | 1 |
| June | 79°F | 60°F | 8 | 4.6 in | 48% | 0 |
| July | 83°F | 65°F | 7 | 4.1 in | 50% | 0 |
| August | 81°F | 63°F | 6 | 4.3 in | 51% | 0 |
| September | 73°F | 54°F | 5 | 3.0 in | 50% | 0 |
| October | 58°F | 41°F | 5 | 2.6 in | 50% | 6 |
| November | 42°F | 28°F | 4 | 1.6 in | 58% | 21 |
| December | 29°F | 15°F | 3 | 1.2 in | 66% | 30 |
*Days with at least 0.1 inch of rain or melted snow. Freezing nights: average nights a month at or below 32°F. Humidity is calculated from NOAA hourly normal temperature and dew point at 3 PM.
Monthly weather in Duluth
| Month | Avg high | Avg low | Wet days* | Rain | 3 PM humidity | Freezing nights |
|---|---|---|---|---|---|---|
| January | 20°F | 2°F | 3 | 0.9 in | 65% | 31 |
| February | 25°F | 6°F | 3 | 1.0 in | 59% | 28 |
| March | 36°F | 18°F | 4 | 1.5 in | 54% | 28 |
| April | 49°F | 30°F | 6 | 2.5 in | 47% | 19 |
| May | 63°F | 41°F | 7 | 3.4 in | 46% | 4 |
| June | 72°F | 50°F | 8 | 4.4 in | 54% | 0 |
| July | 78°F | 56°F | 7 | 3.9 in | 55% | 0 |
| August | 76°F | 55°F | 6 | 3.7 in | 56% | 0 |
| September | 67°F | 47°F | 7 | 3.5 in | 57% | 1 |
| October | 53°F | 36°F | 6 | 2.9 in | 56% | 11 |
| November | 37°F | 23°F | 5 | 2.0 in | 63% | 25 |
| December | 25°F | 10°F | 4 | 1.5 in | 69% | 31 |
Use the averages, then check the forecast
These ratings describe a typical month, not a particular week. A warm spell in a “poor” month can give you a good day, and a wet week can spoil a “good” one. Use this page to plan the season, then check the 7-day forecast for your ZIP code before you buy materials or book help. Each project forecast checks the hours after you finish too: overnight lows, dew and rain that would ruin fresh stain, paint, sealer or concrete.
About this data
Monthly temperatures, rain days, snowfall and freeze dates are NOAA National Centers for Environmental Information (NCEI) U.S. Climate Normals for 1991–2020 at MINNEAPOLIS/ST PAUL AP, DULUTH. Ratings apply the same temperature limits as our forecasts (for example, 50°F or warmer for deck stain and driveway sealer, and no freezing nights for new concrete) to the average month. Your product label always takes priority.
Frequently asked questions
When is the best time to stain a deck in Minnesota?
In Minneapolis–St. Paul, May–September. In Duluth, June–August. Look for at least 24 dry hours before and after, and nights above about 40°F. The deck staining forecast checks your exact week.
When is the last frost in Minnesota?
Minneapolis–St. Paul: around April 23; Duluth: around May 13. These are median dates from NOAA 1991–2020 normals, so a freeze after them happens in about half of years. Low spots and valleys freeze later in spring.
Can you pour concrete in winter in Minnesota?
Yes, but it needs cold-weather practices. Minneapolis–St. Paul averages about 87 freezing nights from December to February, so fresh concrete needs insulated blankets, a heated enclosure or an accelerated mix, and must not freeze in the first 48 hours. Many homeowners wait for spring.
What months are best for sealing a driveway in Minnesota?
In Minneapolis–St. Paul, June–September. In Duluth, July–August. Most sealers need 50°F or warmer for 24 hours and a dry day after. See the driveway sealing forecast.