Weather in Lancaster, Pennsylvania
Roses open along the stoops. Day 59 of spring. Read this microseason across nine climate regions →
- TodayMay 16Overcast—83°47°
- SundayMay 17Overcast14%86°60°
- MondayMay 18Showers17%88°63°
- TuesdayMay 19Showers17%88°64°
- WednesdayMay 20Showers80%85°58°
- ThursdayMay 21Overcast31%69°48°
- FridayMay 22Drizzle37%55°48°
- PM 2.5
- 9.5 μg/m³
- PM 10
- 9.9 μg/m³
- NO₂
- 6.8 μg/m³
- Ozone
- 107.0 μg/m³
- UV Index
- 0.0 Low
When the dew is on the grass, rain will never come to pass.
- Moonrise
- 9:52 AM
- Moonset
- 12:42 AM
- In sign
- ♉︎ Taurus
Roses open along the stoops
Lancaster at a glance
- Today vs. normal: 72°F — typical for the season
- Last frost: April 16 (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 Lancaster's peak warmth with mean temperatures around 76°F, while January delivers the year's coldest conditions near 31°F. September typically sees the heaviest rainfall at 4.8 inches, with February marking the driest period at 2.5 inches.
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 31° | 3.0″ | 6 |
| February | 33° | 2.5″ | 6 |
| March | 41° | 3.5″ | 7 |
| April | 53° | 3.5″ | 7 |
| May | 62° | 3.6″ | 7 |
| June | 71° | 4.1″ | 7 |
| July | 76° | 4.5″ | 7 |
| August | 74° | 3.6″ | 6 |
| September | 67° | 4.8″ | 6 |
| October | 55° | 4.2″ | 6 |
| November | 44° | 3.3″ | 5 |
| December | 36° | 3.5″ | 7 |
Regional context
Lancaster falls within a warm-summer humid continental climate region, sharing temperature ranges, seasonal rhythms, and growing conditions with other cities in this climate category.
Similar climates: Philadelphia, PA, Pittsburgh, PA, Allentown, PA, Harrisburg, PA, Scranton, PA.
Naturalist notes
May brings the distinctive calls of wood warblers returning through Lancaster's woodlands during their northward migration.
Apple trees across the region typically reach full bloom in late April, their white and pink flowers marking the transition from spring's last frosts.
Frequently asked
- When does it freeze in Lancaster?
- Spring's final frost in Lancaster typically occurs around mid-April, while the first fall frost returns around mid-November.
- What is the rainy season in Lancaster?
- September ranks as the wettest month, delivering about 4.8 inches of rain on average, contributing to the city's annual total of roughly 44 inches.
- What is the warmest month in Lancaster?
- July typically records the year's highest temperatures, averaging about 76°F.
- What is the coldest month in Lancaster?
- January typically brings the coldest conditions, averaging about 31°F.
- When can I start a vegetable garden in Lancaster?
- Cool-season crops like peas and lettuce can be planted around the last spring frost in mid-April, while warm-season crops such as tomatoes and peppers should wait 1–2 weeks after.
- How many rainy days does Lancaster get?
- Lancaster experiences about 76 rainy days per year on average.
- What hardiness zone is Lancaster?
- Lancaster's USDA hardiness zone depends on its lowest average winter temperature; the USDA's online lookup tool using the city ZIP code provides the current zone designation.
Climate
Lancaster, Pennsylvania experiences a warm-summer humid continental climate zone. January temperatures typically hover near 31°F while July averages reach 76°F, creating a 45°F seasonal swing.
Annual precipitation totals about 44 inches across roughly 76 rainy days throughout the year.
Weather patterns here follow the influence of latitude at 40.0°N, proximity to large water bodies, and local elevation. These factors determine what plants can grow, when frost threatens, and how daily weather unfolds.