Weather in Dayton, Ohio
Roses open on the Piedmont edge. Day 59 of spring. Read this microseason across nine climate regions →
- TodayMay 16Light Rain68%75°56°
- SundayMay 17Light Drizzle49%85°59°
- MondayMay 18Overcast12%89°62°
- TuesdayMay 19Showers60%82°66°
- WednesdayMay 20Light Showers70%68°55°
- ThursdayMay 21Overcast15%64°48°
- FridayMay 22Light Drizzle25%67°53°
- PM 2.5
- 6.8 μg/m³
- PM 10
- 7.2 μg/m³
- NO₂
- 8.9 μg/m³
- Ozone
- 70.0 μg/m³
- UV Index
- 0.0 Low
When the dew is on the grass, rain will never come to pass.
- Moonrise
- 10:26 AM
- Moonset
- 1:13 AM
- In sign
- ♊︎ Gemini
Roses open on the Piedmont edge
Dayton at a glance
- Today vs. normal: 5°F below the seasonal normal for this latitude
- Last frost: April 15 (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
Warm-season window is open
As of May 17, the last spring frost has passed for most years. Transplant tomatoes, peppers, eggplants, basil, and cucurbits (cucumbers, squash, melons) now. Direct-sow beans and corn into warm soil.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| January | — | — |
| February | — | — |
| March | — | — |
| April | lettuce, peas, spinach, radishes | — |
| May | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| June | tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| July | tomatoes, peppers, beans, squash | tomatoes, beans, summer squash |
| August | — | tomatoes, beans, summer squash |
| September | fall brassicas, garlic (overwinter), carrots | tomatoes, beans, summer squash |
| October | fall brassicas, garlic (overwinter), carrots | winter squash, tomatoes (last) |
| November | — | — |
| December | — | — |
A year in weather
July brings Dayton's warmest temperatures (~76°F mean) while January delivers the coldest (~28°F). Rainfall reaches its peak in April (4.5 inches) and drops to its lowest point in February (2.4 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 28° | 3.2″ | 7 |
| February | 31° | 2.4″ | 5 |
| March | 41° | 3.5″ | 8 |
| April | 53° | 4.5″ | 8 |
| May | 64° | 4.4″ | 9 |
| June | 73° | 4.4″ | 8 |
| July | 76° | 4.0″ | 7 |
| August | 75° | 3.1″ | 6 |
| September | 68° | 3.0″ | 5 |
| October | 55° | 3.0″ | 5 |
| November | 43° | 3.0″ | 6 |
| December | 33° | 3.1″ | 6 |
Regional context
Dayton falls within a humid subtropical climate region — part of a group that shares similar temperature ranges, seasonal patterns, and growing conditions across nearby cities.
Similar climates: Cincinnati, OH, Columbus, OH, Middletown, OH, Newark, OH, Springfield, OH.
Naturalist notes
Late April brings the first ruby-throated hummingbirds back to Dayton's gardens and parks.
May sees the unfurling of American beech leaves throughout local woodlands.
Frequently asked
- When does it freeze in Dayton?
- Dayton's last spring frost typically falls around mid-April, and the first fall frost arrives around mid-November.
- What is the rainy season in Dayton?
- April is the wettest month with about 4.5 inches of rain on average; the city receives roughly 42 inches annually.
- What is the warmest month in Dayton?
- July is typically warmest, averaging about 76°F.
- What is the coldest month in Dayton?
- January is typically coldest, averaging about 28°F.
- When can I start a vegetable garden in Dayton?
- Cool-season crops (peas, lettuce) can be sown around the last spring frost (mid-April); warm-season crops (tomatoes, peppers) wait until 1–2 weeks after.
- How many rainy days does Dayton get?
- Dayton averages about 80 rainy days per year.
- What hardiness zone is Dayton?
- Dayton'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
Dayton, Ohio sits in a humid subtropical climate zone. January temperatures hover near 28°F while July averages 76°F — a 48°F seasonal swing.
Throughout the year, Dayton receives about 42 inches of precipitation spread over roughly 80 rainy days.
Weather patterns follow the city's latitude (39.8°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.