Mechanicsburg, Pennsylvania Weather
Cicadas claim the afternoon. Day 14 of summer. Read this microseason across nine climate regions →
Mechanicsburg weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 4Rain32%0.30″101°74°—
- SundayJul 5Heavy Rain92%2.7″95°72°-6°
- MondayJul 6Light Rain92%0.23″73°65°-22°
- TuesdayJul 7Drizzle68%0.02″72°63°-1°
- WednesdayJul 8Mostly Clear13%—84°58°+12°
- ThursdayJul 9Overcast27%—90°68°+6°
- FridayJul 10Light Drizzle34%—88°70°-2°
AQI 56 (Moderate), driven by Ozone. AQI flat over the last 6 hours (within ±3 points). Ozone at AQI 50 now. With UV 4.3 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 29 around 1 PM.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion during the projected peak around 6 PM.
What's driving it
Ozone × UV × Sky
Ozone at AQI 50 now. With UV 4.3 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 29 around 1 PM.
- Present
- AQI 50
- UV peak
- 4.3 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 29
PM × Wind × Precip
PM2.5 at 8.2 µg/m³, PM10 at 8.7 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.94
- 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).








































If the first of July be rainy weather, 'twill rain more or less for four weeks together.
- Moonrise
- 11:01 PM
- Moonset
- 10:11 AM
- In sign
- ♓︎ Pisces
Cicadas claim the afternoon
Mechanicsburg at a glance
- Today vs. normal: 12°F above the seasonal normal for this latitude
- Last frost: April 17 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
ZIP codes: 17050, 17055
16-Day Forecast — Mechanicsburg
- Sat101°74°32%
- Sun95°72°92%
- Mon73°65°92%
- Tue72°63°68%
- Wed84°58°13%
- Thu90°68°27%
- Fri88°70°34%
- Sat87°70°33%
- Sun75°65°26%
- Mon72°65°17%
- Tue79°64°13%
- Wed87°66°24%
- Thu94°69°26%
- Fri94°74°35%
- Sat83°71°39%
- Sun88°69°42%
Forecast data from Open-Meteo (CC BY 4.0).
Right now in the garden
Peak growing season
As of July 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 — Mechanicsburg
SPC has placed Mechanicsburg in the Slight Risk category for severe thunderstorms today.
- TODAYSLGTSlight Risk
- TOMORROWSLGTSlight Risk
- DAY 3TSTMGeneral Thunderstorms
Scattered severe storms possible. A few tornadoes, hail, and damaging wind gusts possible.
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.
Microseason · July 1–5
Cicadas claim the afternoon
Annual cicada buzz begins, peaking in the heat of the day.
Day 185 of 365 · Wedge 37 of 72
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
Mechanicsburg peaks at about 75°F in July and bottoms near 29°F in January; July brings the heaviest rain (4.8 inches) and February the least (2.8 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 29° | 2.9″ | 6 |
| February | 31° | 2.8″ | 5 |
| March | 39° | 3.9″ | 6 |
| April | 51° | 3.9″ | 8 |
| May | 61° | 4.0″ | 9 |
| June | 71° | 4.0″ | 8 |
| July | 75° | 4.8″ | 7 |
| August | 73° | 4.3″ | 8 |
| September | 65° | 4.6″ | 6 |
| October | 53° | 3.8″ | 7 |
| November | 42° | 2.9″ | 6 |
| December | 34° | 3.4″ | 7 |
Regional context
Drawing on NOAA NCEI 1991-2020 normals, Mechanicsburg's January averages 29°F and July 75°F — 46°F apart — while precipitation totals roughly 45.2 inches over some 82 days.
Mechanicsburg's precipitation spreads evenly: July peaks at 4.8 inches on 7.4 wet days, while February holds 2.8 inches over 5.3 — no month dominates Mechanicsburg's rain calendar. It is a balanced pattern Mechanicsburg shares with places like Shiremanstown, PA, New Kingstown, PA and Messiah College, PA.
By mid-April the frosts ease in Mechanicsburg, opening the season for kale, peas, spinach, and parsnips. Hold Mechanicsburg's tender crops — tomatoes, peppers, basil — until 10-14 days past Mechanicsburg's last frost. Around mid-November, freezing nights resume in Mechanicsburg and tender crops must come in. Within Mechanicsburg, cold-air pooling chills low spots by 5-10°F, shifting Mechanicsburg's local frost dates.
Similar climates: Shiremanstown, PA, New Kingstown, PA, Messiah College, PA, Camp Hill, PA, Lemoyne, PA.
Frequently asked
- When does it freeze in Mechanicsburg?
- In Mechanicsburg, expect the last spring frost near mid-April; Mechanicsburg's first autumn frost comes around mid-November.
- What is the rainy season in Mechanicsburg?
- Rainfall in Mechanicsburg peaks in July near 4.8 inches, out of about 45 inches annually.
- What is the warmest month in Mechanicsburg?
- The warmest stretch in Mechanicsburg comes in July, around 75°F on average.
- What is the coldest month in Mechanicsburg?
- On average January is the chilliest month in Mechanicsburg, about 29°F.
- When can I start a vegetable garden in Mechanicsburg?
- Mechanicsburg's last frost (mid-April) cues hardy greens; in Mechanicsburg, hold heat-lovers two weeks past.
- How many rainy days does Mechanicsburg get?
- Mechanicsburg records around 82 days of measurable precipitation annually.
- What hardiness zone is Mechanicsburg?
- Mechanicsburg's hardiness zone tracks its winter low; with January near 29°F, check the USDA ZIP map for the exact zone.
- What is the 10-day forecast for Mechanicsburg?
- Mechanicsburg's extended outlook — daily high and low temperatures and precipitation chances for each upcoming day — is in the daily forecast above.
- Will it rain this week in Mechanicsburg?
- See this week's day-by-day rain chances for Mechanicsburg in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in Mechanicsburg?
- Current conditions for Mechanicsburg and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the Mechanicsburg forecast updated?
- The Mechanicsburg forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in Mechanicsburg?
- Today's sunrise and sunset times for Mechanicsburg are in the Almanac section above, along with civil dawn, civil dusk, and day length. Day length is longest near the summer solstice and shortest near the winter solstice.
- How accurate is the weather forecast for Mechanicsburg?
- The next few days in Mechanicsburg's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
Climate
Mechanicsburg, Pennsylvania occupies a warm-summer humid continental zone, with January means near 29°F and July around 75°F — a 46°F swing.
Rain and snow bring Mechanicsburg roughly 45 inches a year across approximately 82 measurable-precipitation days.
Latitude 40.2°N gives Mechanicsburg its 46°F swing, and with it the rhythm of Mechanicsburg's growing season.
ZIP codes in Mechanicsburg
- 17055