Hardly any U.S. towns see harsher January nights than Portage Township
Sunny July days climb to about 82°. Expect the heaviest rain or snow in June and the lightest in January. By precipitation alone, it ranks drier than 88% of U.S. towns. Garden chairs stay out from May to September, the months with highs of 68–82°.
A year in Portage Township at a glance
Each month’s typical high and low, and what it brings.
What stands out about Portage Township’s climate
Compared with towns across the U.S., with Portage Township’s place in South Dakota beside it.
What a year in Portage Township feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 135 frost-free days a year
In half of years the last 32° night comes by May 13 and the first by September 26. Frost and day counts come from NOAA’s station at Britton, SD, 16 miles from the town’s center, at about the same height.
The 2023 USDA map puts Portage Township’s center in zone 4a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −26°. 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 45 inches of snow a winter
Snow, measured at Britton, SD, falls mostly in February and December. Precipitation (rain plus melted snow) adds up to 23 inches a year; June is the wettest month and January the driest. Rain or snow falls on about 82 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Portage Township
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 Britton, SD.
Living with Portage Township’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
135 frost-free days in zone 4a. The last frost comes by May 13 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Sep 26.
Months with highs of 62–84° and lows of 40° or more: May, June, July, August and September. 8.9 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Portage Township from natural hazards, river flooding is the largest share (38%); heat waves, cold waves, winter storms and ice storms together are 38%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Portage Township and its neighbors
Every town next door is within a degree of Portage Township in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Portage Township’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 |
|---|---|---|---|---|
| Portage Township, SD | 2° | 82° | 23" | 45" |
| Mandan, ND | 3° | 84° | 18" | 51" |
| Litchfield, MN | 4° | 82° | 28" | 41" |
| Spirit Lake, IA | 7° | 83° | 31" | 42" |
| Kingsford, MI | 5° | 80° | 29" | 61" |
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 Portage Township averaged 1.0° warmer than the 1900s. The biggest change is in January (+3.2°).
A smaller shift than in 75% 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 Portage Township compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Portage Township’s place among South Dakota’s.
Portage Township weather by month
Highs, lows and precipitation from NOAA’s grid at Portage Township’s center; snow, wet days and snow on the ground from Britton, SD. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | 30-yr range |
|---|---|---|---|---|---|---|
| January | 20° | 2° | 0.6" | 8.3" | 5 | −3° – 25° |
| February | 25° | 6° | 0.6" | 9.8" | 5 | −1° – 28° |
| March | 39° | 19° | 0.9" | 6.1" | 5 | 18° – 43° |
| April | 55° | 31° | 1.8" | 5.1" | 7 | 32° – 51° |
| May | 68° | 44° | 3.2" | 0.0" | 10 | 51° – 62° |
| June | 78° | 55° | 3.9" | 0.0" | 10 | 61° – 71° |
| July | 82° | 59° | 3.7" | 0.0" | 9 | 63° – 76° |
| August | 81° | 57° | 2.6" | 0.0" | 8 | 63° – 73° |
| September | 72° | 47° | 2.4" | 0.0" | 7 | 53° – 64° |
| October | 57° | 34° | 2.1" | 1.2" | 7 | 37° – 51° |
| November | 39° | 20° | 0.7" | 5.1" | 5 | 17° – 40° |
| December | 26° | 8° | 0.6" | 9.8" | 5 | 4° – 25° |
| Year | 53° | 32° | 23.0" | 45.4" | 82 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from -1° to 28°. August is the most reliable, staying within 10°.
Where Portage Township’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 Portage Township’s center.
- Snow: Britton, SD.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Britton, SD, 16 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 Portage Township’s climate
What is the weather like in Portage Township?
A typical July afternoon reaches 82°, a January night drops to 2°, and about 45 inches of snow falls in a normal winter. Colder January nights than all but 79 U.S. towns; cooler July afternoons than 77% of U.S. towns.
How cold does it get in Portage Township in winter?
January nights average 2°. About 170 nights a year reach 32° or below and 36 reach 0° or below. In the coldest January of the last 30 years the month averaged −3°.
How much snow does Portage Township get?
About 45 inches in a normal winter at Britton, SD, most of it in February and December.
How hot does it get in Portage Township?
July, with a typical high of 82° and a low of 59°. About 16 days a year reach 90° (Britton, SD).
When is the first and last frost in Portage Township?
In half of years the last spring frost (32°) comes by May 13 and the first fall frost by September 26, about 135 frost-free days, at Britton, SD.
What growing zone is Portage Township in?
Zone 4a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −26°.
What is the best time of year to visit Portage Township?
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 Portage Township getting warmer?
Yes: 1991–2020 averaged 1.0° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 75% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Portage Township.
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.