Radnor, United States experiences average highs of 17°C (63°F) and lows of 9°C (48°F) throughout the year. Rainfall is moderate, averaging about 11 rainy days per month. Average highs have cooled by 0.8°C (1.4°F) across the available records.
Radnor, United States Weather & Climate 2026
Monthly climate averages for Radnor, United States. Based on 10-year ERA5 reanalysis data.
Climate Overview
Drier season: Jan–Dec 
Wetter season: Mar–Aug At-a-Glance Climate Summary
Live Weather & Air Quality
Key figures
Climate Score
5.5/10
Best: May, June, August, September, October
UV Index
5
Low
Temperature 17°C / 9°C
Feels Like 16°C / 7°C
Rainy Days 11
Rainfall 97 mm
Sunshine 8 h
Humidity 69%
Wind Speed 17 km/h
Dew Point 8°C
Snow Days 3 days
Frost Days 12 days
Hottest Month
30°C
July
Avg Low21°C
Rain14days
Coldest Month
-2°C
January
Avg High5°C
Rain10days
Driest Month
8days
October
Avg High19°C
Avg Low11°C
Windiest Month
20 km/h
March (Gusts 43)
Worst Time to Visit
Consider avoiding January, February, December due to very cold temperatures, frequent rain.
Sun Position
Sunrise 05:33
Daylight 15h
Sunset 20:33
Live conditions—
Radnor on the map · live conditions
Radnor, United States
- Continent
- Americas
- Country
- United States
- City
- Radnor
- Population
- 30.9K
- Elevation
- 132 m
- Coordinates
- 40.05°, -75.36°
Seasonal Breakdown
Spring
Mar–May
Avg High 17°C
Avg Low 7°C
Rain 11 days/mo
1/3 best months
Summer
Jun–Aug
Avg High 28°C
Avg Low 20°C
Rain 12 days/mo
2/3 best months
Autumn
Sep–Nov
Avg High 19°C
Avg Low 11°C
Rain 8 days/mo
2/3 best months
Winter
Dec–Feb
Avg High 6°C
Avg Low -1°C
Rain 10 days/mo
Climate Charts
Based on historical averages (2016–2025)
Monthly Temperatures
HighLowShaded bands show the typical range across the available yearly records.
Line chart showing monthly temperatures. Jan: 5°C / -2°C . Feb: 7°C / -1°C . Mar: 12°C / 2°C . Apr: 17°C / 7°C . May: 22°C / 12°C . Jun: 27°C / 18°C . Jul: 30°C / 21°C . Aug: 28°C / 20°C . Sep: 25°C / 17°C . Oct: 19°C / 11°C . Nov: 12°C / 4°C . Dec: 7°C / 0°C .
Monthly Rainfall
Rainfall
Bar chart showing monthly rainfall. Jan: 82 mm. Feb: 90 mm. Mar: 99 mm. Apr: 101 mm. May: 113 mm. Jun: 90 mm. Jul: 125 mm. Aug: 103 mm. Sep: 94 mm. Oct: 88 mm. Nov: 73 mm. Dec: 100 mm.
Monthly Humidity
Humidity
Line chart showing monthly humidity. Jan: 66%. Feb: 67%. Mar: 64%. Apr: 65%. May: 71%. Jun: 69%. Jul: 73%. Aug: 73%. Sep: 73%. Oct: 72%. Nov: 68%. Dec: 70%.
Monthly Wind Speed
Wind SpeedGusts
Bar chart showing monthly wind speed. Jan: 19 km/h . Feb: 19 km/h . Mar: 20 km/h . Apr: 20 km/h . May: 17 km/h . Jun: 16 km/h . Jul: 14 km/h . Aug: 14 km/h . Sep: 15 km/h . Oct: 16 km/h . Nov: 18 km/h . Dec: 18 km/h .
Sunshine
Sunshine
Sunshine: Jan: 6h. Feb: 7h. Mar: 8h. Apr: 9h. May: 9h. Jun: 11h. Jul: 12h. Aug: 10h. Sep: 9h. Oct: 8h. Nov: 7h. Dec: 6h.
UV Index
UV Index
Bar chart showing monthly UV index. Jan: UV 2. Feb: UV 3. Mar: UV 5. Apr: UV 5. May: UV 6. Jun: UV 7. Jul: UV 7. Aug: UV 6. Sep: UV 5. Oct: UV 4. Nov: UV 3. Dec: UV 2.
Monthly Daylight Hours
Daylight12h reference
Monthly Dew Point & Comfort
Dew Point Dry Comfortable Humid Muggy Oppressive
Snow Days
Snow DaysSnowfall
Snow Days: Jan: 5 days. Feb: 5 days. Mar: 2 days. Apr: 0 days. May: 0 days. Jun: 0 days. Jul: 0 days. Aug: 0 days. Sep: 0 days. Oct: 0 days. Nov: 1 days. Dec: 3 days.
Climate Trends
Average highs have cooled by 0.8°C (1.4°F) across the available records. Average rainfall has remained broadly steady.
2016 to 2025
Avg high Avg rainfall
Climate summary
| Last 12 months | All years | |
|---|---|---|
| Hottest month | Jul 2025 · 30°C | Jul · 30°C |
| Coldest month | Jan 2025 · -5°C | Jan · -2°C |
| Wettest month | Jul 2025 · 160 mm | Jul · 125 mm |
| Windiest month | Mar 2025 · 22 km/h | Mar · 20 km/h |
Month-by-Month Weather Table
January
Poor 
February
Poor March
Poor April
Fair May best
Excellent June best
Excellent July
Good August best
Excellent September best
Excellent October best
Good November
Fair December
Poor | Month | Temp | Feels Like | Rain | Sun | Humidity | UV | Status | Details |
|---|---|---|---|---|---|---|---|---|
| January | 5°C / -2°C | 0°C / -7°C | 10days (82 mm) Wet | 5.9h Fair | 66% Muggy | 2.4 Moderate | Poor | View Details |
| February | 7°C / -1°C | 4°C / -5°C | 10days (90 mm) Wet | 6.7h Fair | 67% Muggy | 3.3 Moderate | Poor | View Details |
| March | 12°C / 2°C | 8°C / -2°C | 11days (99 mm) Wet | 8.1h Good | 64% Muggy | 4.5 Moderate | Poor | View Details |
| April | 17°C / 7°C | 15°C / 4°C | 10days (101 mm) Wet | 9h Good | 65% Muggy | 5.2 High | Fair | View Details |
| May best | 22°C / 12°C | 22°C / 11°C | 13days (113 mm) Wet | 9.3h Good | 71% Muggy | 5.9 High | Excellent | View Details |
| June best | 27°C / 18°C | 28°C / 18°C | 11days (90 mm) Wet | 11.4h Excellent | 69% Muggy | 6.9 High | Excellent | View Details |
| July | 30°C / 21°C | 33°C / 24°C | 14days (125 mm) Wet | 11.6h Excellent | 73% Muggy | 7.1 Very High | Good | View Details |
| August best | 28°C / 20°C | 30°C / 22°C | 12days (103 mm) Wet | 10.4h Excellent | 73% Muggy | 6.4 High | Excellent | View Details |
| September best | 25°C / 17°C | 26°C / 17°C | 9days (94 mm) Wet | 8.6h Good | 73% Muggy | 5 Moderate | Excellent | View Details |
| October best | 19°C / 11°C | 18°C / 9°C | 8days (88 mm) Wet | 7.5h Good | 72% Muggy | 4.2 Moderate | Good | View Details |
| November | 12°C / 4°C | 9°C / 1°C | 8days (73 mm) Wet | 7.1h Good | 68% Muggy | 2.8 Moderate | Fair | View Details |
| December | 7°C / 0°C | 3°C / -4°C | 10days (100 mm) Wet | 5.6h Fair | 70% Muggy | 2.1 Moderate | Poor | View Details |
Compare Nearby City Climates
Frequently Asked Questions
The best months to visit Radnor are May, June, August, September, October, when temperatures are comfortable and rainfall is at its lowest. This is based on 10-year climate averages for Radnor, scoring temperature, rainfall, humidity, and sunshine hours.
The hottest month in Radnor is July, with average daytime highs of 30°C (85°F). Plan outdoor activities for early morning or late afternoon if visiting during this period.
The coldest month in Radnor is January, with average overnight lows of -2°C (28°F). Pack warm layers and expect shorter daylight hours during this period.
The wettest month in Radnor is July, averaging 125mm of precipitation across 14 rainy days. An umbrella or waterproof jacket is essential.
The rainy season in Radnor runs through July, May, August, March, with the heaviest rainfall in July. Based on 10-year averages for Radnor.
Radnor receives approximately 101 sunshine hours per year. The sunniest month is July with around 12 hours. Based on climate data for Radnor.
The least favorable months to visit Radnor are January, February, December, primarily due to very cold temperatures, frequent rain. For the best conditions, consider May, June, August, September, October instead.
The annual average UV index in Radnor is 5, classified as moderate. Standard sun protection (sunscreen, hat) is recommended during prolonged outdoor exposure.
Average humidity in Radnor is 69%, classified as moderate. Humidity levels are generally comfortable and should not affect outdoor activities for most people.
Yes, Radnor receives snow. Months with snowfall average 3 snow days and 9 cm (4 in) of accumulation, with about 12 frost days during winter.
Average wind speeds in Radnor are 17 km/h (11 mph). The windiest month is March with peak winds reaching 20 km/h (12 mph) (gusts up to 43 km/h / 27 mph).
Radnor averages 4 clear-sky days per month with overall cloud cover around 58%. The clearest skies occur in November.
The annual average dew point in Radnor is 8°C (46°F), which feels dry and comfortable. Outdoor activities are comfortable year-round from a humidity standpoint.
Radnor has a Humid Subtropical climate, classified as Cfa under the Köppen system. Temperate climates have mild winters and warm summers, with rainfall spread across the year and four distinct seasons.
The 'feels like' temperature in Radnor ranges from 7°C (45°F) to 16°C (61°F) on average. The 'feels like' temperature closely matches the actual temperature throughout most of the year.
Yes, June is a great time to visit Radnor. It earns a climate score of 8.5/10 with Excellent.
For June in Radnor, pack Umbrella, Waterproof jacket, Breathable clothing, Sunscreen (SPF 30+), Sun hat. With average highs of 27°C (80°F) and 11 rainy days, these essentials will keep you comfortable.
Data Source
Climate data derived from ERA5 reanalysis (ECMWF), averaged over 2016–2025. Sea surface temperature from marine reanalysis data. Climate scores and seasonal estimates are computed by WorldStats.
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