Johnstown, United States experiences average highs of 16°C (61°F) and lows of 7°C (45°F) throughout the year. Rainfall is frequent, averaging about 14 rainy days per month. Average highs have stayed broadly stable across the available records.
Johnstown, United States Weather & Climate 2026
Monthly climate averages for Johnstown, United States. Based on 10-year ERA5 reanalysis data.
Climate Overview
Drier season: Feb–Dec 
Wetter season: Jan–Jun At-a-Glance Climate Summary
Live Weather & Air Quality
Key figures
Climate Score
5/10
Best: May, June, July, August, September
UV Index
5
Low
Temperature 16°C / 7°C
Feels Like 15°C / 5°C
Rainy Days 14
Rainfall 109 mm
Sunshine 8 h
Humidity 76%
Wind Speed 17 km/h
Dew Point 7°C
Snow Days 8 days
Frost Days 16 days
Hottest Month
28°C
July
Avg Low19°C
Rain14days
Coldest Month
-5°C
January
Avg High3°C
Rain16days
Driest Month
10days
October
Avg High18°C
Avg Low9°C
Windiest Month
21 km/h
March (Gusts 52)
Worst Time to Visit
Consider avoiding January, February, March, December due to very cold temperatures, frequent rain.
Sun Position
Sunrise 05:47
Daylight 15h
Sunset 20:48
Live conditions—
Johnstown on the map · live conditions
Johnstown, United States
- Continent
- Americas
- Country
- United States
- City
- Johnstown
- Population
- 20K
- Elevation
- 356 m
- Coordinates
- 40.33°, -78.92°
Seasonal Breakdown
Spring
Mar–May
Avg High 16°C
Avg Low 6°C
Rain 15 days/mo
1/3 best months
Summer
Jun–Aug
Avg High 27°C
Avg Low 18°C
Rain 14 days/mo
3/3 best months
Autumn
Sep–Nov
Avg High 17°C
Avg Low 9°C
Rain 11 days/mo
1/3 best months
Winter
Dec–Feb
Avg High 5°C
Avg Low -3°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: 3°C / -5°C . Feb: 6°C / -3°C . Mar: 10°C / 1°C . Apr: 16°C / 5°C . May: 21°C / 11°C . Jun: 25°C / 16°C . Jul: 28°C / 19°C . Aug: 27°C / 18°C . Sep: 24°C / 15°C . Oct: 18°C / 9°C . Nov: 10°C / 2°C . Dec: 5°C / -2°C .
Monthly Rainfall
Rainfall
Bar chart showing monthly rainfall. Jan: 104 mm. Feb: 109 mm. Mar: 101 mm. Apr: 126 mm. May: 155 mm. Jun: 132 mm. Jul: 102 mm. Aug: 94 mm. Sep: 106 mm. Oct: 96 mm. Nov: 82 mm. Dec: 104 mm.
Monthly Humidity
Humidity
Line chart showing monthly humidity. Jan: 77%. Feb: 73%. Mar: 70%. Apr: 72%. May: 79%. Jun: 77%. Jul: 78%. Aug: 77%. Sep: 77%. Oct: 76%. Nov: 74%. Dec: 76%.
Monthly Wind Speed
Wind SpeedGusts
Bar chart showing monthly wind speed. Jan: 20 km/h . Feb: 21 km/h . Mar: 21 km/h . Apr: 20 km/h . May: 17 km/h . Jun: 15 km/h . Jul: 13 km/h . Aug: 13 km/h . Sep: 14 km/h . Oct: 16 km/h . Nov: 19 km/h . Dec: 20 km/h .
Sunshine
Sunshine
Sunshine: Jan: 5h. Feb: 6h. Mar: 8h. Apr: 9h. May: 10h. Jun: 11h. Jul: 11h. Aug: 11h. Sep: 9h. Oct: 7h. Nov: 6h. Dec: 5h.
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 7. 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: 16 days. Feb: 11 days. Mar: 8 days. Apr: 4 days. May: 1 days. Jun: 0 days. Jul: 0 days. Aug: 0 days. Sep: 0 days. Oct: 0 days. Nov: 6 days. Dec: 12 days.
Climate Trends
Average highs have stayed broadly stable 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 · 28°C | Jul · 28°C |
| Coldest month | Jan 2025 · -9°C | Jan · -5°C |
| Wettest month | May 2025 · 247 mm | May · 155 mm |
| Windiest month | Mar 2025 · 22 km/h | Mar · 21 km/h |
Month-by-Month Weather Table
January
Poor 
February
Poor March
Poor April
Poor May best
Good June best
Excellent July best
Excellent August best
Excellent September best
Excellent October
Good November
Poor December
Poor | Month | Temp | Feels Like | Rain | Sun | Humidity | UV | Status | Details |
|---|---|---|---|---|---|---|---|---|
| January | 3°C / -5°C | -2°C / -10°C | 16days (104 mm) Wet | 5h Fair | 77% Humid | 2.2 Moderate | Poor | View Details |
| February | 6°C / -3°C | 2°C / -8°C | 13days (109 mm) Wet | 6h Fair | 73% Muggy | 3.2 Moderate | Poor | View Details |
| March | 10°C / 1°C | 7°C / -4°C | 14days (101 mm) Wet | 7.5h Good | 70% Muggy | 4.6 Moderate | Poor | View Details |
| April | 16°C / 5°C | 14°C / 2°C | 15days (126 mm) Wet | 8.7h Good | 72% Muggy | 5.3 High | Poor | View Details |
| May best | 21°C / 11°C | 21°C / 10°C | 17days (155 mm) Wet | 9.7h Good | 79% Humid | 6.3 High | Good | View Details |
| June best | 25°C / 16°C | 27°C / 16°C | 15days (132 mm) Wet | 10.8h Excellent | 77% Humid | 6.8 High | Excellent | View Details |
| July best | 28°C / 19°C | 31°C / 21°C | 14days (102 mm) Wet | 11.1h Excellent | 78% Humid | 7 High | Excellent | View Details |
| August best | 27°C / 18°C | 29°C / 20°C | 14days (94 mm) Wet | 10.7h Excellent | 77% Humid | 6.5 High | Excellent | View Details |
| September best | 24°C / 15°C | 25°C / 15°C | 11days (106 mm) Wet | 9.1h Good | 77% Humid | 5 Moderate | Excellent | View Details |
| October | 18°C / 9°C | 16°C / 7°C | 10days (96 mm) Wet | 7.4h Good | 76% Humid | 3.8 Moderate | Good | View Details |
| November | 10°C / 2°C | 7°C / -2°C | 12days (82 mm) Wet | 6.2h Fair | 74% Muggy | 2.5 Moderate | Poor | View Details |
| December | 5°C / -2°C | 1°C / -6°C | 14days (104 mm) Wet | 4.7h Fair | 76% Humid | 1.9 Low | Poor | View Details |
Compare Nearby City Climates
Frequently Asked Questions
The best months to visit Johnstown are May, June, July, August, September, when temperatures are comfortable and rainfall is at its lowest. This is based on 10-year climate averages for Johnstown, scoring temperature, rainfall, humidity, and sunshine hours.
The hottest month in Johnstown is July, with average daytime highs of 28°C (82°F). Plan outdoor activities for early morning or late afternoon if visiting during this period.
The coldest month in Johnstown is January, with average overnight lows of -5°C (23°F). Pack warm layers and expect shorter daylight hours during this period.
The wettest month in Johnstown is May, averaging 155mm of precipitation across 17 rainy days. An umbrella or waterproof jacket is essential.
The rainy season in Johnstown runs through May, January, April, June, with the heaviest rainfall in May. Based on 10-year averages for Johnstown.
Johnstown receives approximately 97 sunshine hours per year. The sunniest month is July with around 11 hours. Based on climate data for Johnstown.
The least favorable months to visit Johnstown are January, February, March, December, primarily due to very cold temperatures, frequent rain. For the best conditions, consider May, June, July, August, September instead.
The annual average UV index in Johnstown is 5, classified as moderate. Standard sun protection (sunscreen, hat) is recommended during prolonged outdoor exposure.
Average humidity in Johnstown is 76%, classified as humid. Humidity levels are generally comfortable and should not affect outdoor activities for most people.
Yes, Johnstown receives snow. Months with snowfall average 8 snow days and 15 cm (6 in) of accumulation, with about 16 frost days during winter.
Average wind speeds in Johnstown are 17 km/h (11 mph). The windiest month is March with peak winds reaching 21 km/h (13 mph) (gusts up to 52 km/h / 32 mph).
Johnstown averages 3 clear-sky days per month with overall cloud cover around 65%. The clearest skies occur in October.
The annual average dew point in Johnstown is 7°C (45°F), which feels dry and comfortable. Outdoor activities are comfortable year-round from a humidity standpoint.
Johnstown 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 Johnstown ranges from 5°C (41°F) to 15°C (59°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 Johnstown. It earns a climate score of 8/10 with Excellent.
For June in Johnstown, pack Umbrella, Waterproof jacket, Waterproof shoes, Breathable clothing, Sunscreen (SPF 30+). With average highs of 25°C (77°F) and 15 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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