PORT HURON, MI

Overview:
Port Huron is the county seat of St. Clair County, and it is connected to Port Edward, Ontario in Canada via the Blue Water Bridge. Located on the southern tip of Lake Huron along the St. Clair River, a temperate climate similar to much of the surrounding area in lower Michigan is observed in Port Huron.

While winds generally blow from the south-southwest, lake breezes affect temperatures in the transition seasons. Maximum temperatures in the low 80s are common during the summer months, with record values only near 100°F. Extreme minimum temperatures of -20°F or colder are rare due to the lake influence.

State/ Province ID: MI

Station ID: C00206680

Directory Name: PORT_HURON__MI_C00206680

Elevation: 179.80m


The resources presented here were developed in cooperation with the Office of the Michigan State Climatologist using data from the National Centers for Environmental Information. For more information regarding our data sources, quality control, and methodology, please see our Historical Climatologies: Quality Control reference guide.

Recent Climate Summary, 1991-2020

Average Temperature49.3°F9.6°C
Average Low Temperature41.2°F5.1°C
Average High Temperature57.3°14.1°C
Days/Year that exceed 90°F7.5 
Days/Year that fall below 32°F113.3 
Lowest Annual Average Temperature46.9°F8.3°C
Highest Annual Average Temperature52.2°F11.2°C
Average Annual Total Precipitation35.0 in89.0 cm
Lowest Annual Precipitation Total27.4 in69.5 cm
Highest Annual Precipitation Total45.1 in114.6 cm
Days/Year that exceed 1.25" of Precipitation3.6 

Temperature

Click on the following links to be taken to the corresponding portion of the page.

  • Monthly Average Temperature
  • How Temperatures are Changing
    • Changes in Average Temperature – Includes a summary table of the average annual and seasonal temperature changes, and time series graphs of how the annual low, average, and high temperatures compare to the long term average plotted for every year on record.
    • Cold Temperatures – View time series plots of the number of days per year below 32°F and the number of heating degree days per year to see how cold days are changing.
    • Hot Temperatures – View time series plots of the number of days per year above 90°F and the number of cooling degree days per year to see how hot days are changing.
    • Growing Season Changes – View a time series of the annual number of days in the freeze-free period.

Monthly Average Temperature

Changes in Average Temperature, 1951-2025.

 °F°C
Annual average temperature2.01.1
Winter average temperature2.31.3
Spring average temperature1.70.9
Summer average temperature1.91.1
Fall average temperature1.30.7

Annual High and Low Temperature Departure

Cold Temperatures

¹Heating Degree Days (HDDs) are indexed units, not actual days, that roughly describe the demand to heat a building. HDDs accumulate on days colder than 65°F when heating is required. Every degree below 65°F is added to the annual total for an annual HDD value, which is plotted in the figure.

Hot Temperatures

²Cooling Degree Days (CDDs) are indexed units, not actual days, that roughly describe the demand to cool a building. CDDs accumulate on days warmer than 65°F when cooling is required. Every degree above 65°F is added to the annual total for an annual CDD value, which is plotted in the figure.

Growing Season Changes

Precipitation

Click on the following links to be taken to the corresponding portion of the page.

  • Monthly Average Precipitation – View a graph of the monthly low, average, and high precipitation climatology (average) of the past 30 years
  • How Precipitation is Changing
    • Changes in Total Precipitation – Includes a summary table of the average annual and seasonal precipitation changes.
    • Heavy Precipitation – View a bar chart of how annual number of days receiving more than 1, 1.25, 1.5, 1.75, and 2 inches of precipitation are changing over the period of record.

Monthly Average Precipitation

Changes in Average Precipitation, 1951-2025.

 in.cm.%
Annual total precipitation4.411.114.40
Winter total precipitation1.53.926.90
Spring total precipitation0.82.09.70
Summer total precipitation0.71.77.30
Fall total precipitation1.64.021.70

Heavy Precipitation