Penn Wynne, Pennsylvania Weather
Cicadas claim the afternoon. Day 14 of summer. Read this microseason across nine climate regions →
Penn Wynne weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 4Light Drizzle43%0.01″102°76°—
- SundayJul 5Rain89%0.66″96°71°-6°
- MondayJul 6T-storm w/ Hail89%0.29″78°66°-18°
- TuesdayJul 7Light Drizzle72%—67°62°-11°
- WednesdayJul 8Mostly Clear16%—86°59°+19°
- ThursdayJul 9Mostly Clear28%—91°67°+5°
- FridayJul 10Light Drizzle34%—93°72°+2°
AQI 64 (Moderate), driven by PM2.5. AQI up 8 over the last 6 hours (gradual rise). PM2.5 at 20.0 µg/m³ (AQI 71) with a 0.89 fine-to-coarse ratio and 5 mph wind — combustion smoke trapped in calm air, not road dust.
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 45 now. With UV 4.7 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 28 around 1 PM.
- Present
- AQI 45
- UV peak
- 4.7 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 28
PM × Wind × Precip
PM2.5 at 20.0 µg/m³ (AQI 71) with a 0.89 fine-to-coarse ratio and 5 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.89
- Wind
- light
- Recent rain
- 0h in last 6h
- Pattern
- stagnant smoke
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
- 10:54 PM
- Moonset
- 10:04 AM
- In sign
- ♓︎ Pisces
Cicadas claim the afternoon
Penn Wynne at a glance
- Today vs. normal: 11°F above the seasonal normal for this latitude
- Last frost: April 16 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
16-Day Forecast — Penn Wynne
- Sat102°76°43%
- Sun96°71°89%
- Mon78°66°89%
- Tue67°62°72%
- Wed86°59°16%
- Thu91°67°28%
- Fri93°72°34%
- Sat83°72°34%
- Sun74°68°32%
- Mon72°67°17%
- Tue82°65°16%
- Wed92°68°24%
- Thu95°74°23%
- Fri97°78°34%
- Sat79°71°39%
- Sun89°70°35%
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 — Penn Wynne
SPC has placed Penn Wynne 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
Penn Wynne peaks at about 77°F in July and bottoms near 31°F in January; December brings the heaviest rain (4.2 inches) and February the least (2.9 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 31° | 3.4″ | 13 |
| February | 33° | 2.9″ | 12 |
| March | 42° | 3.7″ | 15 |
| April | 53° | 3.9″ | 17 |
| May | 61° | 3.7″ | 17 |
| June | 71° | 3.7″ | 17 |
| July | 77° | 3.3″ | 16 |
| August | 75° | 4.0″ | 17 |
| September | 69° | 3.7″ | 13 |
| October | 58° | 3.0″ | 11 |
| November | 45° | 3.6″ | 13 |
| December | 36° | 4.2″ | 13 |
Regional context
Per NOAA NCEI 1991-2020 normals, Penn Wynne runs from a 31°F January mean to 77°F in July, a 46°F seasonal spread, with near 43.1 inches of precipitation across about 173 wet days.
Penn Wynne's precipitation spreads evenly: December peaks at 4.2 inches on 13.0 wet days, while February holds 2.9 inches over 12.4 — no month dominates Penn Wynne's rain calendar. That even rhythm groups Penn Wynne with places like Wynnewood, PA, Narberth, PA and Merion Station, PA.
Penn Wynne reaches its last hard frost near mid-April; that is the cue for peas, lettuce, spinach, and radishes. Penn Wynne's heat-lovers — tomatoes, peppers, squash — hold off until Penn Wynne's frost risk clears, 10-14 days on. Frost returns to Penn Wynne near mid-November, ending the tender-crop season. Penn Wynne's low ground holds frost later into spring than Penn Wynne's benches, which run 3-5 days ahead.
Similar climates: Wynnewood, PA, Narberth, PA, Merion Station, PA, Ardmore, PA, Millbourne, PA.
Frequently asked
- When does it freeze in Penn Wynne?
- Frost typically leaves Penn Wynne by mid-April and returns to Penn Wynne near mid-November.
- What is the rainy season in Penn Wynne?
- Rainfall in Penn Wynne peaks in December near 4.2 inches, out of about 43 inches annually.
- What is the warmest month in Penn Wynne?
- On average July tops the year in Penn Wynne at about 77°F.
- What is the coldest month in Penn Wynne?
- The coldest stretch in Penn Wynne falls in January, around 31°F on average.
- When can I start a vegetable garden in Penn Wynne?
- Hardy spring crops go in near mid-April in Penn Wynne; tender peppers and squash wait 10–14 days.
- How many rainy days does Penn Wynne get?
- Penn Wynne records around 173 days of measurable precipitation annually.
- What hardiness zone is Penn Wynne?
- With January around 31°F, Penn Wynne's zone reflects that minimum — the USDA ZIP map confirms Penn Wynne's band.
- What is the 10-day forecast for Penn Wynne?
- Penn Wynne'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 Penn Wynne?
- See this week's day-by-day rain chances for Penn Wynne in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in Penn Wynne?
- Current conditions for Penn Wynne and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the Penn Wynne forecast updated?
- The Penn Wynne forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in Penn Wynne?
- Today's sunrise and sunset times for Penn Wynne 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 Penn Wynne?
- The next few days in Penn Wynne's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
Climate
Set in a warm-summer humid continental zone, Penn Wynne, Pennsylvania swings from 31°F in the heart of winter to 77°F at midsummer — a 46°F arc.
Yearly precipitation in Penn Wynne totals around 43 inches, spread over about 173 days of rain or snow.
Penn Wynne sits at 40.0°N; that 46°F seasonal swing frames planting windows and frost dates across Penn Wynne.
ZIP codes in Penn Wynne
- 19096