Michigan weather and outdoor projects
Michigan’s weather is shaped by the Great Lakes. Detroit in the southeast has the longest warm season, Grand Rapids in the west gets more lake-effect clouds and snow, and the Upper Peninsula around Sault Ste. Marie has a short summer and long winter. The lakes keep spring cool near the shore and keep fall mild a little longer.
June through mid-September is the main window for staining and painting in most of the state. Cloudy, damp stretches are common in fall near the lakes, which slows drying. Hard freezes and freeze-thaw cycles make fall concrete and driveway work time-sensitive.
Frost dates in Michigan
In Detroit, the median last spring freeze (32°F) is around April 20 and the median first fall freeze is around October 27, a frost-free season of about 188 days.
In Grand Rapids, the median last spring freeze (32°F) is around April 29 and the median first fall freeze is around October 20, a frost-free season of about 174 days.
In Sault Ste. Marie, the median last spring freeze (32°F) is around May 9 and the median first fall freeze is around October 11, a frost-free season of about 151 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 Michigan
In Detroit, 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 40°F. April is cool, with highs around 59°F, so choose the warmest afternoons. In October, nights average about 44°F, so finish early on mild days and check the overnight low.
In Grand Rapids, the most reliable months are May–September. October can also work on the right days. November–March is too cold, with average highs around 39°F. In April, nights average about 37°F, too cold for the coating to dry and cure overnight. October is cool, with highs around 61°F, so choose the warmest afternoons.
In Sault Ste. Marie, 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 37°F. In May, nights average about 41°F, so finish early on mild days and check the overnight low. September averages about 8 wet days a month, so wait for a clear stretch.
Check this week’s hour-by-hour verdict with the deck staining forecast.
Best time to paint outside in Michigan
In Detroit, 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 40°F. In April and October, nights average about 42°F, so finish early on mild days and check the overnight low.
In Grand Rapids, 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 39°F. April is cool, with highs around 58°F, so choose the warmest afternoons. In October, nights average about 42°F, so finish early on mild days and check the overnight low.
In Sault Ste. Marie, the most reliable months are June–August. May and September–October can also work on the right days. November–April is too cold, with average highs around 34°F. In May, nights average about 41°F, so finish early on mild days and check the overnight low. September averages about 8 wet days a month, so wait for a clear stretch. October is cool, with highs around 54°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 Michigan
In Detroit, the most reliable months are May–September. April and October can also work on the right days. November–March averages about 22 nights a month at or below 32°F, so fresh concrete needs blankets or heated enclosures. April and October bring about 4 freezing nights a month, so pick a mild spell and keep curing blankets on hand.
In Grand Rapids, the most reliable months are May–September. October can also work on the right days. November–April averages about 21 nights a month at or below 32°F, so fresh concrete needs blankets or heated enclosures. October brings about 4 freezing nights a month, so pick a mild spell and keep curing blankets on hand.
In Sault Ste. Marie, the most reliable months are June–September. May and October can also work on the right days. November–April averages about 25 nights a month at or below 32°F, so fresh concrete needs blankets or heated enclosures. May and October bring about 6 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 Michigan
In Detroit, 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 43°F. In May, nights average about 50°F, so finish early on mild days and check the overnight low. October is cool, with highs around 62°F, so choose the warmest afternoons.
In Grand Rapids, 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 42°F. In May, nights average about 49°F, so finish early on mild days and check the overnight low. October is cool, with highs around 61°F, so choose the warmest afternoons.
In Sault Ste. Marie, 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 37°F. In May, nights average about 41°F, too cold for the coating to dry and cure overnight. In June and September, nights average about 49°F, so finish early on mild days and check the overnight low.
Check this week’s hour-by-hour verdict with the driveway sealing forecast.
Best time to fertilize or treat a lawn in Michigan
In Detroit, the most reliable months are May–October. April can also work on the right days. November–March is too cold, with average highs around 40°F. April is cool, with highs around 59°F, so choose the warmest afternoons.
In Grand Rapids, the most reliable months are May–October. April can also work on the right days. November–March is too cold, with average highs around 39°F. April is cool, with highs around 58°F, so choose the warmest afternoons.
In Sault Ste. Marie, the most reliable months are May–September. October can also work on the right days. November–April is too cold, with average highs around 34°F. October is cool, with highs around 54°F, so choose the warmest afternoons.
Check this week’s hour-by-hour verdict with the lawn fertilizer forecast.
How the weather differs across Michigan
| Place | Hottest month avg high | Coldest month avg low | Rain per year | Last spring freeze | First fall freeze |
|---|---|---|---|---|---|
| Detroit | 84°F | 19°F | 34 in | April 20 | October 27 |
| Grand Rapids | 83°F | 19°F | 39 in | April 29 | October 20 |
| Sault Ste. Marie | 77°F | 8°F | 34 in | May 9 | October 11 |
Of the places above, Detroit has the most good months for staining, painting and concrete combined (15 job-months), and Sault Ste. Marie has the fewest (10). If you live between them, expect something in between, and higher ground to be cooler with a shorter season.
Monthly weather in Detroit
| Month | Avg high | Avg low | Wet days* | Rain | 3 PM humidity | Freezing nights |
|---|---|---|---|---|---|---|
| January | 32°F | 19°F | 6 | 2.2 in | 66% | 27 |
| February | 35°F | 21°F | 5 | 2.1 in | 60% | 25 |
| March | 46°F | 29°F | 6 | 2.4 in | 51% | 21 |
| April | 59°F | 39°F | 7 | 3.3 in | 45% | 6 |
| May | 70°F | 50°F | 8 | 3.7 in | 48% | 0 |
| June | 80°F | 60°F | 6 | 3.3 in | 49% | 0 |
| July | 84°F | 64°F | 6 | 3.5 in | 50% | 0 |
| August | 81°F | 63°F | 6 | 3.3 in | 52% | 0 |
| September | 74°F | 56°F | 6 | 3.2 in | 51% | 0 |
| October | 62°F | 44°F | 6 | 2.5 in | 53% | 2 |
| November | 49°F | 34°F | 6 | 2.6 in | 58% | 14 |
| December | 37°F | 25°F | 5 | 2.3 in | 65% | 24 |
*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 Grand Rapids
| Month | Avg high | Avg low | Wet days* | Rain | 3 PM humidity | Freezing nights |
|---|---|---|---|---|---|---|
| January | 31°F | 19°F | 7 | 2.5 in | 71% | 28 |
| February | 34°F | 20°F | 6 | 2.1 in | 65% | 25 |
| March | 45°F | 27°F | 6 | 2.4 in | 54% | 23 |
| April | 58°F | 37°F | 8 | 4.0 in | 47% | 10 |
| May | 70°F | 49°F | 8 | 4.0 in | 48% | 1 |
| June | 79°F | 58°F | 6 | 3.9 in | 50% | 0 |
| July | 83°F | 63°F | 6 | 3.9 in | 51% | 0 |
| August | 81°F | 61°F | 6 | 3.5 in | 53% | 0 |
| September | 74°F | 53°F | 6 | 3.4 in | 53% | 0 |
| October | 61°F | 42°F | 8 | 4.0 in | 56% | 4 |
| November | 47°F | 33°F | 7 | 3.1 in | 62% | 16 |
| December | 36°F | 25°F | 7 | 2.5 in | 70% | 26 |
Monthly weather in Sault Ste. Marie
| Month | Avg high | Avg low | Wet days* | Rain | 3 PM humidity | Freezing nights |
|---|---|---|---|---|---|---|
| January | 24°F | 8°F | 7 | 2.2 in | 69% | 30 |
| February | 26°F | 9°F | 5 | 1.5 in | 64% | 28 |
| March | 36°F | 18°F | 5 | 1.8 in | 56% | 28 |
| April | 49°F | 30°F | 7 | 2.6 in | 49% | 18 |
| May | 63°F | 41°F | 6 | 2.6 in | 48% | 4 |
| June | 73°F | 50°F | 6 | 2.9 in | 54% | 0 |
| July | 77°F | 55°F | 6 | 3.1 in | 56% | 0 |
| August | 76°F | 55°F | 7 | 3.2 in | 57% | 0 |
| September | 68°F | 49°F | 8 | 3.9 in | 60% | 0 |
| October | 54°F | 39°F | 10 | 4.4 in | 64% | 7 |
| November | 41°F | 28°F | 9 | 3.4 in | 69% | 20 |
| December | 31°F | 17°F | 8 | 2.8 in | 73% | 29 |
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 DETROIT METRO AP, GRAND RAPIDS, SAULT STE MARIE SANDERSON FLD. 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 Michigan?
In Detroit, May–September. In Grand Rapids, May–September. In Sault Ste. Marie, 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 Michigan?
Detroit: around April 20; Grand Rapids: around April 29; Sault Ste. Marie: around May 9. 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 Michigan?
Yes, but it needs cold-weather practices. Detroit averages about 77 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 Michigan?
In Detroit, June–September. In Grand Rapids, June–September. In Sault Ste. Marie, July–August. Most sealers need 50°F or warmer for 24 hours and a dry day after. See the driveway sealing forecast.