Nights turn raw in Mullen Township each January, colder than in 91% of U.S. towns
On a normal July day the thermometer tops out near 89°. It is a dry place: less rain and snow fall here than on 89% of U.S. towns. The latest 30-year average runs 1.0° warmer than 1901–2000’s, with January up the most. Garden planting can start around May 3; autumn frost returns near October 9.
A year in Mullen Township at a glance
Each month’s typical high and low, and what it brings.
What stands out about Mullen Township’s climate
Compared with towns across the U.S., with Mullen Township’s place in South Dakota beside it.
What a year in Mullen Township feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 158 frost-free days a year
In half of years the last 32° night comes by May 3 and the first by October 9. Frost and day counts come from NOAA’s station at Murdo, SD, 8 miles from the town’s center, 260 ft higher.
The 2023 USDA map puts Mullen Township’s center in zone 5a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −17°. 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 49 inches of snow a winter
Snow, measured at Murdo, SD, falls mostly in December. Precipitation (rain plus melted snow) adds up to 20 inches a year; June is the wettest month and January the driest. Rain or snow falls on about 91 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Mullen Township
89% 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 Murdo, SD.
Living with Mullen Township’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
158 frost-free days in zone 5a. The last frost comes by May 3 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 9.
Months with highs of 62–84° and lows of 40° or more: May, June and September. 5.0 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Mullen Township from natural hazards, river flooding is the largest share (45%); heat waves, cold waves, winter storms and ice storms together are 23%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Mullen Township and similar climates
TownRatings has no climate map of the towns around Mullen Township yet.
Climates most like Mullen 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 |
|---|---|---|---|---|
| Mullen Township, SD | 12° | 89° | 20" | 49" |
| Providence, UT | 15° | 89° | 19" | 44" |
| Alliance, NE | 13° | 88° | 17" | 45" |
| Preston, ID | 14° | 89° | 15" | 52" |
| Longmont, CO | 16° | 90° | 16" | 47" |
Temperatures and precipitation come from NOAA’s 5 km grid; snow and day counts from the stations named on this page.
Warmer than it used to be
The last 30 years in Mullen Township averaged 1.0° warmer than the 1900s. The biggest change is in January (+3.7°).
A smaller shift than in 76% 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 Mullen Township compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Mullen Township’s place among South Dakota’s.
Mullen Township weather by month
Highs, lows and precipitation from NOAA’s grid at Mullen Township’s center; snow, wet days and snow on the ground from Murdo, SD. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | 30-yr range |
|---|---|---|---|---|---|---|
| January | 34° | 12° | 0.5" | 7.5" | 6 | 14° – 37° |
| February | 37° | 15° | 0.6" | 8.5" | 6 | 9° – 38° |
| March | 48° | 24° | 1.0" | 8.1" | 6 | 24° – 50° |
| April | 59° | 33° | 2.2" | 6.8" | 9 | 38° – 52° |
| May | 70° | 45° | 3.3" | 0.0" | 13 | 51° – 63° |
| June | 81° | 55° | 3.4" | 0.0" | 11 | 63° – 73° |
| July | 89° | 62° | 2.6" | 0.0" | 8 | 67° – 82° |
| August | 87° | 59° | 2.3" | 0.0" | 8 | 67° – 78° |
| September | 78° | 49° | 1.6" | 0.0" | 6 | 57° – 69° |
| October | 63° | 36° | 1.6" | 1.8" | 7 | 40° – 56° |
| November | 48° | 24° | 0.6" | 5.6" | 5 | 24° – 45° |
| December | 36° | 15° | 0.5" | 10.8" | 5 | 14° – 33° |
| Year | 61° | 36° | 20.1" | 49.1" | 91 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 9° to 38°. June is the most reliable, staying within 10°.
Where Mullen 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 Mullen Township’s center.
- Snow: Murdo, SD.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Murdo, SD, 8 miles from the town’s center, 260 ft higher; 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 Mullen Township’s climate
What is the weather like in Mullen Township?
A typical July afternoon reaches 89°, a January night drops to 12°, and about 49 inches of snow falls in a normal winter. Colder January nights than 91% of U.S. towns; hotter July afternoons than 72% of U.S. towns.
How cold does it get in Mullen Township in winter?
January nights average 12°. About 157 nights a year reach 32° or below and 19 reach 0° or below. In the coldest January of the last 30 years the month averaged 14°.
How much snow does Mullen Township get?
About 49 inches in a normal winter at Murdo, SD, most of it in December.
How hot does it get in Mullen Township?
July, with a typical high of 89° and a low of 62°. About 34 days a year reach 90° and 5 reach 100° (Murdo, SD).
When is the first and last frost in Mullen Township?
In half of years the last spring frost (32°) comes by May 3 and the first fall frost by October 9, about 158 frost-free days, at Murdo, SD.
What growing zone is Mullen Township in?
Zone 5a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −17°.
What is the best time of year to visit Mullen Township?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Mullen Township getting warmer?
Yes: 1991–2020 averaged 1.0° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 76% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Mullen 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.