Olean, United States experiences average highs of 14°C (57°F) and lows of 5°C (41°F) throughout the year. Rainfall is frequent, averaging about 13 rainy days per month. Average highs have cooled by 1.1°C (2.0°F) across the available records.
Olean, United States Weather & Climate 2026
Monthly climate averages for Olean, United States. Based on 10-year ERA5 reanalysis data.
Climate Overview
Drier season: Feb–Nov 
Wetter season: Jan–Dec At-a-Glance Climate Summary
Live Weather & Air Quality
Key figures
Climate Score
4.7/10
Best: June, July, August, September
UV Index
4
Low
Temperature 14°C / 5°C
Feels Like 12°C / 3°C
Rainy Days 13
Rainfall 95 mm
Sunshine 8 h
Humidity 76%
Wind Speed 17 km/h
Dew Point 5°C
Snow Days 10 days
Frost Days 17 days
Hottest Month
26°C
July
Avg Low17°C
Rain14days
Coldest Month
-7°C
January
Avg High0°C
Rain15days
Driest Month
9days
September
Avg High22°C
Avg Low13°C
Windiest Month
20 km/h
March (Gusts 50)
Worst Time to Visit
Consider avoiding January, February, March, December due to very cold temperatures, frequent rain.
Sun Position
Sunrise 05:39
Daylight 15.2h
Sunset 20:52
Live conditions—
Olean on the map · live conditions
Olean, United States
- Continent
- Americas
- Country
- United States
- City
- Olean
- Population
- 13.9K
- Elevation
- 441 m
- Coordinates
- 42.08°, -78.43°
Seasonal Breakdown
Spring
Mar–May
Avg High 13°C
Avg Low 4°C
Rain 14 days/mo
Summer
Jun–Aug
Avg High 25°C
Avg Low 16°C
Rain 13 days/mo
3/3 best months
Autumn
Sep–Nov
Avg High 15°C
Avg Low 7°C
Rain 11 days/mo
1/3 best months
Winter
Dec–Feb
Avg High 2°C
Avg Low -6°C
Rain 14 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: 0°C / -7°C . Feb: 3°C / -6°C . Mar: 7°C / -2°C . Apr: 13°C / 3°C . May: 19°C / 10°C . Jun: 24°C / 14°C . Jul: 26°C / 17°C . Aug: 25°C / 17°C . Sep: 22°C / 13°C . Oct: 16°C / 8°C . Nov: 8°C / 1°C . Dec: 2°C / -4°C .
Monthly Rainfall
Rainfall
Bar chart showing monthly rainfall. Jan: 87 mm. Feb: 87 mm. Mar: 90 mm. Apr: 114 mm. May: 112 mm. Jun: 103 mm. Jul: 91 mm. Aug: 101 mm. Sep: 84 mm. Oct: 104 mm. Nov: 81 mm. Dec: 85 mm.
Monthly Humidity
Humidity
Line chart showing monthly humidity. Jan: 78%. Feb: 75%. Mar: 70%. Apr: 70%. May: 75%. Jun: 75%. Jul: 76%. Aug: 77%. Sep: 78%. Oct: 78%. Nov: 77%. Dec: 79%.
Monthly Wind Speed
Wind SpeedGusts
Bar chart showing monthly wind speed. Jan: 19 km/h . Feb: 20 km/h . Mar: 20 km/h . Apr: 19 km/h . May: 16 km/h . Jun: 15 km/h . Jul: 14 km/h . Aug: 13 km/h . Sep: 14 km/h . Oct: 17 km/h . Nov: 19 km/h . Dec: 19 km/h .
Sunshine
Sunshine
Sunshine: Jan: 5h. Feb: 6h. Mar: 7h. Apr: 8h. May: 10h. Jun: 11h. Jul: 11h. Aug: 10h. Sep: 9h. Oct: 7h. Nov: 5h. Dec: 4h.
UV Index
UV Index
Bar chart showing monthly UV index. Jan: UV 2. Feb: UV 3. Mar: UV 4. Apr: UV 5. May: UV 6. Jun: UV 7. Jul: UV 7. Aug: UV 6. Sep: UV 5. Oct: UV 3. Nov: UV 2. 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: 18 days. Feb: 14 days. Mar: 11 days. Apr: 7 days. May: 1 days. Jun: 0 days. Jul: 0 days. Aug: 0 days. Sep: 0 days. Oct: 1 days. Nov: 9 days. Dec: 16 days.
Climate Trends
Average highs have cooled by 1.1°C (2.0°F) across the available records. Average rainfall is trending wetter by about 9 mm.
2016 to 2025
Avg high Avg rainfall
Climate summary
| Last 12 months | All years | |
|---|---|---|
| Hottest month | Jul 2025 · 27°C | Jul · 26°C |
| Coldest month | Jan 2025 · -9°C | Jan · -7°C |
| Wettest month | May 2025 · 168 mm | Apr · 114 mm |
| Windiest month | Mar 2025 · 22 km/h | Mar · 20 km/h |
Month-by-Month Weather Table
January
Poor 
February
Poor March
Poor April
Poor May
Good June best
Excellent July best
Excellent August best
Excellent September best
Excellent October
Fair November
Poor December
Poor | Month | Temp | Feels Like | Rain | Sun | Humidity | UV | Status | Details |
|---|---|---|---|---|---|---|---|---|
| January | 0°C / -7°C | -4°C / -12°C | 15days (87 mm) Wet | 4.5h Fair | 78% Humid | 1.9 Low | Poor | View Details |
| February | 3°C / -6°C | -2°C / -11°C | 13days (87 mm) Wet | 5.8h Fair | 75% Muggy | 3 Moderate | Poor | View Details |
| March | 7°C / -2°C | 4°C / -7°C | 13days (90 mm) Wet | 7.3h Good | 70% Muggy | 4.2 Moderate | Poor | View Details |
| April | 13°C / 3°C | 11°C / 0°C | 15days (114 mm) Wet | 8.4h Good | 70% Muggy | 4.8 Moderate | Poor | View Details |
| May | 19°C / 10°C | 18°C / 8°C | 15days (112 mm) Wet | 9.6h Good | 75% Muggy | 5.8 High | Good | View Details |
| June best | 24°C / 14°C | 24°C / 14°C | 13days (103 mm) Wet | 11.1h Excellent | 75% Muggy | 6.7 High | Excellent | View Details |
| July best | 26°C / 17°C | 28°C / 18°C | 14days (91 mm) Wet | 11.3h Excellent | 76% Humid | 6.9 High | Excellent | View Details |
| August best | 25°C / 17°C | 26°C / 17°C | 13days (101 mm) Wet | 10.4h Excellent | 77% Humid | 5.9 High | Excellent | View Details |
| September best | 22°C / 13°C | 22°C / 13°C | 9days (84 mm) Wet | 8.8h Good | 78% Humid | 5 Moderate | Excellent | View Details |
| October | 16°C / 8°C | 14°C / 5°C | 12days (104 mm) Wet | 6.9h Fair | 78% Humid | 3.4 Moderate | Fair | View Details |
| November | 8°C / 1°C | 4°C / -3°C | 13days (81 mm) Wet | 5.3h Fair | 77% Humid | 2.2 Moderate | Poor | View Details |
| December | 2°C / -4°C | -2°C / -9°C | 15days (85 mm) Wet | 3.9h Poor | 79% Humid | 1.6 Low | Poor | View Details |
Compare Nearby City Climates
Frequently Asked Questions
The best months to visit Olean are June, July, August, September, when temperatures are comfortable and rainfall is at its lowest. This is based on 10-year climate averages for Olean, scoring temperature, rainfall, humidity, and sunshine hours.
The hottest month in Olean is July, with average daytime highs of 26°C (79°F). Plan outdoor activities for early morning or late afternoon if visiting during this period.
The coldest month in Olean is January, with average overnight lows of -7°C (19°F). Pack warm layers and expect shorter daylight hours during this period.
The wettest month in Olean is April, averaging 114mm of precipitation across 15 rainy days. An umbrella or waterproof jacket is essential.
The rainy season in Olean runs through January, April, May, December, with the heaviest rainfall in January. Based on 10-year averages for Olean.
Olean receives approximately 93 sunshine hours per year. The sunniest month is July with around 11 hours. Based on climate data for Olean.
The least favorable months to visit Olean are January, February, March, December, primarily due to very cold temperatures, frequent rain. For the best conditions, consider June, July, August, September instead.
The annual average UV index in Olean is 4, classified as moderate. Standard sun protection (sunscreen, hat) is recommended during prolonged outdoor exposure.
Average humidity in Olean is 76%, classified as humid. Humidity levels are generally comfortable and should not affect outdoor activities for most people.
Yes, Olean receives snow. Months with snowfall average 10 snow days and 17 cm (7 in) of accumulation, with about 17 frost days during winter.
Average wind speeds in Olean are 17 km/h (11 mph). The windiest month is March with peak winds reaching 20 km/h (13 mph) (gusts up to 50 km/h / 31 mph).
Olean averages 2 clear-sky days per month with overall cloud cover around 68%. The clearest skies occur in September.
The annual average dew point in Olean is 5°C (41°F), which feels dry and comfortable. Outdoor activities are comfortable year-round from a humidity standpoint.
Olean has a Warm-Summer Continental climate, classified as Dfb under the Köppen system. Continental climates experience extreme temperature ranges — hot summers and cold, snowy winters.
The 'feels like' temperature in Olean ranges from 3°C (37°F) to 12°C (54°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 Olean. It earns a climate score of 8.4/10 with Excellent.
For June in Olean, pack Umbrella, Waterproof jacket, Sunscreen (SPF 30+), Sunglasses, Comfortable walking shoes. With average highs of 24°C (74°F) and 13 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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