Summer arrives softly in Bay Port, cooler than in 93% of U.S. towns
On a normal January night the air cools to about 17°. It is a dry place: less rain and snow fall here than on 85% of U.S. towns. Warming shows here too: 1.7° more than in 1901–2000, led by December. The frost-free window for a garden runs roughly May 8 to October 17.
A year in Bay Port at a glance
Each month’s typical high and low, and what it brings.
What stands out about Bay Port’s climate
Compared with towns across the U.S., with Bay Port’s place in Michigan beside it.
What a year in Bay Port feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 162 frost-free days a year
In half of years the last 32° night comes by May 8 and the first by October 17. Frost and day counts come from NOAA’s station at Filion 5nnw, MI, 15 miles from the town’s center, at about the same height.
The 2023 USDA map puts Bay Port’s center in zone 6a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −6°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
About 43 inches of snow a winter
Snow, measured at Cass City 1 Ssw, MI, falls mostly in January. Precipitation (rain plus melted snow) adds up to 31 inches a year; July is the wettest month and February the driest. Rain or snow falls on about 138 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Bay Port
95% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from October through April.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Filion 5nnw, MI.
Living with Bay Port’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
162 frost-free days in zone 6a. The last frost comes by May 8 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Oct 17.
Months with highs of 62–84° and lows of 40° or more: May, June, July, August and September. 0.7 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Bay Port from natural hazards, river flooding is the largest share (50%); heat waves, cold waves, winter storms and ice storms together are 31%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Bay Port and its neighbors
Every town next door is within a degree of Bay Port in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Bay Port’s, farther away
TownRatings’ own comparison of NOAA 1991–2020 normals, not a NOAA product: places of 5,000+ at least 150 miles away, one per state, closest on January low, July high, precipitation and snow.
| Town | Jan. low | July high | Precip. | Snow |
|---|---|---|---|---|
| Bay Port, MI | 17° | 80° | 31" | 43" |
| Port Washington, WI | 15° | 80° | 33" | 42" |
| Le Roy, NY | 17° | 80° | 35" | 52" |
| Winthrop Harbor, IL | 17° | 81° | 36" | 36" |
| Sandusky, OH | 22° | 82° | 36" | 33" |
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value. Snow and frost-free days come from the nearest weather station, so neighbors often share them.
Warmer than it used to be
The last 30 years in Bay Port averaged 1.7° warmer than the 1900s. The biggest change is in December (+2.9°).
A bigger shift than in 70% of U.S. towns.
Change by month
The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods.
How Bay Port compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Bay Port’s place among Michigan’s.
Bay Port weather by month
Highs, lows and precipitation from NOAA’s grid at Bay Port’s center; snow, wet days and snow on the ground from Cass City 1 Ssw, MI. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | 30-yr range |
|---|---|---|---|---|---|---|
| January | 30° | 17° | 1.8" | 14.4" | 14 | 12° – 33° |
| February | 32° | 17° | 1.5" | 9.3" | 10 | 10° – 33° |
| March | 40° | 25° | 1.7" | 5.0" | 10 | 22° – 46° |
| April | 53° | 35° | 3.1" | 1.6" | 12 | 36° – 49° |
| May | 65° | 45° | 3.3" | 0.0" | 12 | 47° – 60° |
| June | 75° | 55° | 3.3" | 0.0" | 10 | 60° – 70° |
| July | 80° | 60° | 3.3" | 0.0" | 9 | 64° – 75° |
| August | 78° | 60° | 3.3" | 0.0" | 11 | 64° – 73° |
| September | 72° | 52° | 3.0" | 0.0" | 10 | 56° – 66° |
| October | 59° | 42° | 2.9" | 0.1" | 12 | 46° – 58° |
| November | 46° | 32° | 2.3" | 3.1" | 13 | 32° – 45° |
| December | 35° | 23° | 1.9" | 9.0" | 13 | 19° – 38° |
| Year | 55° | 39° | 31.3" | 42.5" | 138 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 10° to 33°. June is the most reliable, staying within 10°.
Where Bay Port’s numbers come from
Normals are 30-year averages, not a forecast. How TownRatings reads climate data →
- Temperatures and precipitation: NOAA’s gridded 1991–2020 normals for the 5 km cell at Bay Port’s center.
- Snow: Cass City 1 Ssw, MI.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Filion 5nnw, MI, 15 miles from the town’s center, at about the same height; the nearest station that passes our checks for distance, height and agreement with the grid.
- Growing zone: USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu/phzm, accessed 8 Oct 2026.
- Then and now: NOAA’s gridded normals for 1901–2000 at the same cell.
- Storms and extremes: FEMA National Risk Index (expected annual losses to buildings).
Common questions about Bay Port’s climate
What is the weather like in Bay Port?
A typical July afternoon reaches 80°, a January night drops to 17°, and about 43 inches of snow falls in a normal winter. Colder January nights than 77% of U.S. towns; cooler July afternoons than 93% of U.S. towns.
How cold does it get in Bay Port in winter?
January nights average 17°. About 151 nights a year reach 32° or below and 9 reach 0° or below. In the coldest January of the last 30 years the month averaged 12°.
How much snow does Bay Port get?
About 43 inches in a normal winter at Cass City 1 Ssw, MI, most of it in January.
How hot does it get in Bay Port?
July, with a typical high of 80° and a low of 60°. About 5 days a year reach 90° (Filion 5nnw, MI).
When is the first and last frost in Bay Port?
In half of years the last spring frost (32°) comes by May 8 and the first fall frost by October 17, about 162 frost-free days, at Filion 5nnw, MI.
What growing zone is Bay Port in?
Zone 6a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −6°.
What is the best time of year to visit Bay Port?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June, July, August and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Bay Port getting warmer?
Yes: 1991–2020 averaged 1.7° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 70% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Bay Port.
Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000; USDA/PRISM 2023 hardiness zones; FEMA National Risk Index. Today’s forecast: National Weather Service.