Harrisburg, South Dakota Weather
Prairie lightning bugs rise. Day 77 of spring. Read this microseason across nine climate regions →
Harrisburg weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Overcast33%—85°66°—
- FridayJun 5Overcast16%—86°63°+1°
- SaturdayJun 6Overcast12%—85°61°-1°
- SundayJun 7Light Drizzle34%—84°66°-1°
- MondayJun 8Thunderstorm34%—89°66°+5°
- TuesdayJun 9Thunderstorm23%0.27″87°66°-2°
- WednesdayJun 10Thunderstorm18%—98°75°+11°
PM2.5 at 7.3 µg/m³, PM10 at 7.9 µg/m³ — typical background levels with no transport signature. AQI flat over the last 6 hours (within ±3 points).
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
What's driving it
Ozone × UV × Sky
Ozone at AQI 36. Overcast through the UV peak window (cloud cover ~99%) — afternoon ozone should stay flat.
- Present
- AQI 36
- UV peak
- 3.4 at 1 PM
- Sky at peak
- overcast
- Projected peak
- AQI 8
PM × Wind × Precip
PM2.5 at 7.3 µg/m³, PM10 at 7.9 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.92
- Wind
- light
- Recent rain
- 0h in last 6h
- Pattern
- background
Trends
Seven days of AQI and PM2.5.
Hourly air-quality data from the Copernicus Atmosphere Monitoring Service, charted across the past and next several days. Dashed lines mark the AQI breakpoints at 50 (Good → Moderate) and 100 (Moderate → Unhealthy for Sensitive Groups).
A summer fog for fair, a winter fog for rain.
- Moonrise
- 5:08 AM
- Moonset
- 2:18 PM
- In sign
- ♒︎ Aquarius
Prairie lightning bugs rise
Harrisburg at a glance
- Today vs. normal: 11°F above the seasonal normal for this latitude
- Last frost: May 7 (climatological average for this latitude)
- Microseason: Jun 1–5
- Planting window: Harvest spring lettuce before it bolts. Sow heat-tolerant greens.
Right now in the garden
Peak growing season
As of June 4, the growing season is at its peak — frost is months away. Continue succession-planting beans and summer squash. Start fall brassicas (broccoli, cabbage, kale) from seed indoors for transplanting in late summer.
SPC Convective Outlook
Storm Prediction Center — Harrisburg
SPC has placed Harrisburg in the Marginal Risk category for severe thunderstorms today.
- TODAYMRGLMarginal Risk
- TOMORROWMRGLMarginal Risk
- DAY 3NONENo severe risk
Isolated severe storms possible. Limited threat for hail or damaging wind.
Source: NOAA / NWS Storm Prediction Center categorical convective outlook. Outlooks are re-issued multiple times per day; this page reflects the most recent SPC polygons covering the city’s coordinates.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| January | — | — |
| February | — | — |
| March | — | — |
| April | — | — |
| May | lettuce, peas, spinach, radishes | lettuce, peas, radishes |
| June | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| July | tomatoes, peppers, beans, squash | tomatoes, beans, summer squash |
| August | tomatoes, peppers, beans, squash, fall brassicas, garlic (overwinter), carrots | tomatoes, beans, summer squash |
| September | fall brassicas, garlic (overwinter), carrots | tomatoes, beans, summer squash |
| October | — | winter squash, tomatoes (last) |
| November | — | — |
| December | — | — |
A year in weather
Harrisburg's warmest month is July (~74°F mean) and its coldest is January (~16°F). Rainfall peaks in June (4.6 inches) and bottoms out in January (0.7 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 16° | 0.7″ | 2 |
| February | 21° | 0.8″ | 3 |
| March | 33° | 1.5″ | 5 |
| April | 46° | 3.0″ | 10 |
| May | 59° | 3.7″ | 12 |
| June | 70° | 4.6″ | 15 |
| July | 74° | 3.3″ | 11 |
| August | 72° | 3.3″ | 11 |
| September | 63° | 3.0″ | 10 |
| October | 49° | 2.3″ | 8 |
| November | 34° | 1.2″ | 4 |
| December | 22° | 0.8″ | 3 |
Regional context
Harrisburg sits within a warm-summer humid continental climate region — a cohort that shares similar temperature ranges, seasonal patterns, and growing conditions across nearby cities.
Similar climates: Sioux Falls, SD, Rapid City, SD, Aberdeen, SD, Brookings, SD, Watertown, SD.
Frequently asked
- When does it freeze in Harrisburg?
- Harrisburg's last spring frost typically falls around mid-May, and the first fall frost arrives around mid-October.
- What is the rainy season in Harrisburg?
- June is the wettest month with about 4.6 inches of rain on average; the city receives roughly 28 inches annually.
- What is the warmest month in Harrisburg?
- July is typically warmest, averaging about 74°F.
- What is the coldest month in Harrisburg?
- January is typically coldest, averaging about 16°F.
- When can I start a vegetable garden in Harrisburg?
- Cool-season crops (peas, lettuce) can be sown around the last spring frost (mid-May); warm-season crops (tomatoes, peppers) wait until 1–2 weeks after.
- How many rainy days does Harrisburg get?
- Harrisburg averages about 94 rainy days per year.
- What hardiness zone is Harrisburg?
- Harrisburg's USDA hardiness zone is determined by its lowest average winter temperature; check the USDA's online lookup with the city ZIP for the current zone designation.
Climate
Harrisburg, South Dakota sits in a warm-summer humid continental climate zone. January means hover near 16°F while July averages 74°F — a 58°F seasonal swing.
Across the year, Harrisburg receives about 28 inches of precipitation spread over roughly 94 rainy days.
The rhythm of the year is set by latitude (43.4°N), proximity to large water bodies, and elevation — all of which shape what grows here, when frost is likely, and what the weather story looks like day to day.