Weather in Shellsburg, Iowa
Roses Bloom Along the Shelter Rows. Day 59 of spring. Read this microseason across nine climate regions →
When the dew is on the grass, rain will never come to pass.
- Moonrise
- 10:49 AM
- Moonset
- 1:55 AM
- In sign
- ♊︎ Gemini
Roses Bloom Along the Shelter Rows
Shellsburg at a glance
- Today vs. normal: NaN°F below the seasonal normal for this latitude
- Last frost: April 29 (climatological average for this latitude)
- Microseason: 28 of 72, May 16–20
- Planting window: Direct sow okra, melons, and southern peas. Thin carrot rows.
Right now in the garden
Cool-season window is open
As of May 17, the cool-season window is open or about to open. Direct-sow peas, lettuce, spinach, radishes, and brassicas now. Hold off on warm-season crops until 1–2 weeks after the last spring frost (around May).
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
Shellsburg's warmest month is July (~73°F mean) and its coldest is January (~20°F). Rainfall peaks in June (5.6 inches) and bottoms out in January (0.9 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 20° | 0.9″ | 3 |
| February | 24° | 1.2″ | 3 |
| March | 37° | 2.0″ | 5 |
| April | 49° | 3.6″ | 7 |
| May | 60° | 4.3″ | 8 |
| June | 70° | 5.6″ | 9 |
| July | 73° | 4.4″ | 6 |
| August | 71° | 4.1″ | 6 |
| September | 63° | 3.4″ | 6 |
| October | 51° | 2.9″ | 5 |
| November | 37° | 2.0″ | 4 |
| December | 25° | 1.6″ | 4 |
Frequently asked
- When does it freeze in Shellsburg?
- Shellsburg's last spring frost typically falls around mid-May, and the first fall frost arrives around mid-October.
- What is the rainy season in Shellsburg?
- June is the wettest month with about 5.6 inches of rain on average; the city receives roughly 36 inches annually.
- What is the warmest month in Shellsburg?
- July is typically warmest, averaging about 73°F.
- What is the coldest month in Shellsburg?
- January is typically coldest, averaging about 20°F.
- When can I start a vegetable garden in Shellsburg?
- 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 Shellsburg get?
- Shellsburg averages about 67 rainy days per year.
- What hardiness zone is Shellsburg?
- Shellsburg'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
Shellsburg, Iowa sits in a warm-summer humid continental climate zone. January means hover near 20°F while July averages 73°F — a 53°F seasonal swing.
Across the year, Shellsburg receives about 36 inches of precipitation spread over roughly 67 rainy days.
The rhythm of the year is set by latitude (42.1°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.