Climate and monthly weather forecastJohnstown, PA
Climate and monthly weather forecast
The climate of Johnstown
Johnstown, Pennsylvania is in the Cfb zone according to the Köppen climate classification, suggesting a marine west coast climate with warm summers. Nestled in the northeastern United States, Johnstown experiences a broad range of weather patterns throughout the year.Monthly average temperatures fluctuate from a chilling low of 18.9°F (-7.3°C) in January to a warm high of 80.2°F (26.8°C) in July. The relative humidity hovers between 78% to 87% all year round, giving the air a consistent sense of moisture. Average rainfall varies each month, reaching its peak at 2.56" (65mm) in May and dropping to its lowest of 1.1" (28mm) in November.
Johnstown's climate includes sporadic snowfall, with January and February seeing averages of 3.98" (101mm) and 4.09" (104mm) respectively while zero inches fall from June to September. The average number of snowfall days ranges from zero in the summer months to 12 days in January. Daylight hours are longer in the summer, reaching up to 15 hours in June, and shorter in winter, dipping to 9.3 hours in December.
The best time to visit Johnstown
The optimal time to visit Johnstown resides in the warm, balmy months of June through August, when average high temperatures are between 72.1°F (22.3°C) to 80.2°F (26.8°C). The bright sun shines for up to 15 hours a day in June, offering ample time to explore the city's attractions. The climatic conditions are favorable for outdoor activities. Rainfall is slightly lesser in these months with averages between 1.69" (43mm) to 2.2" (56mm), making it the ideal time for outdoorsy tourists.The worst time to visit Johnstown
The months of January and February can be inhospitable for visitors due to the extreme cold and consistent snowfall. Average low temperatures can plummet to 18.9°F (-7.3°C) and 21.6°F (-5.8°C) respectively in these months and snowfall amounts to more than 4" (102mm). The city witnesses an average of 12 snowfall days in January, leading to often slippery and icy conditions.Spring weather in Johnstown
Spring invigorates Johnstown starting from March when the average high temperatures range from 44.2°F (6.8°C) to 68°F (20°C) and the low temperatures are between 28.8°F (-1.8°C) to 48.7°F (9.3°C). This season brings increased rainfall with an average of 2.56" (65mm) in May. Increasing daylight hours hinting at summer's arrival contribute to extended outdoor activities.Summer weather in Johnstown
Summer in Johnstown is comfortably warm with an average high temperature reaching its peak at 80.2°F (26.8°C) in July. The average low temperatures remain in the pleasing range of 55°F (12.8°C) to 58.8°F (14.9°C). Ample sunshine for a significant 14.4 to 15 hours a day in June, and marginally lesser on the following summer months allow sunshiny outdoor enjoyment.Autumn weather in Johnstown
Autumn sees a substantial drop in temperatures where the average highs and lows vary from 72.1°F (22.3°C) to 46.6°F (8.1°C) and 52.7°F (11.5°C) to 32°F (0°C) respectively. Average rainfall in this season ranges from 1.46" (37mm) to 1.73" (44mm), making it relatively drier. It is the season when the leaves of deciduous trees change colors adding a vibrant hue to the cityscape.Winter weather in Johnstown
Winter brings in a wave of cold as average high temperatures slide to a range of 30.7°F (-0.7°C) to 46.6°F (8.1°C) and the lows chill down between 18.9°F (-7.3°C) to 32°F (0°C). January and February see the most snowfall, creating a wintry white landscape. However, this also means that the sky remains overcast for most part of the day with cloud coverage of 67% to 72%. Winter's end in February is marked by an approximate 4" (102mm) of snowfall.Weather in January
The chilly weather of Johnstown, Pennsylvania makes a strong appearance in January, with frequent snowfall making the landscape a winter wonderland. These conditions lead to lower visibility, demanding caution while driving. The relative humidity increases, paving the way for a typical wintry ambience alongside shorter daylight hours. Weather in January »Weather in February
While February can still form a part of the harsh winter cherry in Johnstown, Pennsylvania, residents experience a slight increase in temperature and daylight hours. The snowfall decreases compared to the previous month, yet it is still an essential characteristic of the weather. Weather in February »Weather in March
As March arrives, the city of Johnstown, Pennsylvania welcomes the first signs of the spring season. The plots start to transition from a snowy exterior to patches of green. The sun starts making regular appearances, resulting in increased daylight hours, and a corresponding rise in temperature. Weather in March »Weather in April
For those waiting for winter to end in Johnstown, Pennsylvania, April offers a glimmer of hope. Moderate rainfall indicates a shift from snowy to rainy weather, indicating the arrival of spring. Changes in weather might give rise to unpredictable weather conditions causing fluctuations in pressure. Weather in April »Weather in May
The blossoms of May in Johnstown, Pennsylvania truly signal that spring is here. The city experiences longer days and more sunshine hours, conducive for daylight saving activities. The month sees an increased amount of rainfall compared to previous months, inducing a fresh appeal to the environment. Weather in May »Weather in June
The residents of Johnstown, Pennsylvania get to enjoy warm days of early summer in June. The environment gets a bit dryer, offering comfortable humidity levels for outdoor activities. The sunshine lights up the surroundings for a longer duration converging with the longest days of the year. Weather in June »Weather in July
July in Johnstown, Pennsylvania signifies the highest reaches of summer as sweltering heat prevails through the day. The rain provides respite from soaring temperatures and makes it an ideal time to explore the region's natural beauty. Weather in July »Weather in August
Maintaining the rhythm of the previous month, August in Johnstown, Pennsylvania keeps the warmth of summer alive. The hours of daylight start declining, yet the brightness of the sun persists for a significant part of the day. Combined with decreased wind speed, the summer weather reaches a plateau. Weather in August »Weather in September
As Johnstown, Pennsylvania slips into autumn in September, the hours of daylight and temperatures see a gradual reduction. The arrival of autumn is marked with foliage beginning to turn different hues. Rainfall pairs up with these conditions, creating a picturesque landscape. Weather in September »Weather in October
Residents of Johnstown, Pennsylvania observe autumn proceeding in full swing in October. From delightful autumnal colors to moderate temperatures, the characteristics of this season are at their peak. Rainfall is seen frequently, providing nourishment to the vivid foliage. Weather in October »Weather in November
On entering November, Johnstown, Pennsylvania prepares to bid adieu to the fall. The weather gets brisk and cold as temperatures fall further. The shorter days and longer nights give a glimpse of the approaching winter. Unsurprisingly, the mercury takes a plunge down to 32°F (0°C). Weather in November »Weather in December
Although less extreme than its consecutive months, December in Johnstown, Pennsylvania does not fall short in terms of its wintry essence. The cold wind, low temperatures, and short days define a typical winter environment. A minor detail not to overlook is the increased percentage of humidity towards the end of the year. Weather in December »Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature
Johnstown, PA
The warmest month (with the highest average high temperature) is July (80.2°F).
The month with the lowest average high temperature is January (30.7°F).
The month with the highest average low temperature is July (58.8°F).
The coldest month (with the lowest average low temperature) is January (18.9°F).
Average pressure
Johnstown, PA
- Average pressure in January:
30.11"Hg - Average pressure in February:
30.08"Hg - Average pressure in March:
30.08"Hg - Average pressure in April:
29.98"Hg - Average pressure in May:
30"Hg - Average pressure in June:
29.95"Hg
- Average pressure in July:
29.98"Hg - Average pressure in August:
30"Hg - Average pressure in September:
30.06"Hg - Average pressure in October:
30.03"Hg - Average pressure in November:
30.14"Hg - Average pressure in December:
30.11"Hg
The month with the highest atmospheric pressure is November (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.95"Hg).
Average wind speed
Johnstown, PA
- Average wind speed in January:
10.1mph - Average wind speed in February:
9.7mph - Average wind speed in March:
8.9mph - Average wind speed in April:
8.9mph - Average wind speed in May:
7.2mph - Average wind speed in June:
6.5mph
- Average wind speed in July:
5.5mph - Average wind speed in August:
5.2mph - Average wind speed in September:
5.9mph - Average wind speed in October:
7.6mph - Average wind speed in November:
8.3mph - Average wind speed in December:
9.4mph
The windiest month (with the highest average wind speed) is January (10.1mph).
The calmest month (with the lowest average wind speed) is August (5.2mph).
Average humidity
Johnstown, PA
The month with the highest relative humidity is February (87%).
The month with the lowest relative humidity is July (78%).
Average rainfall
Johnstown, PA
- Average rainfall in January:
1.38" - Average rainfall in February:
1.61" - Average rainfall in March:
1.73" - Average rainfall in April:
1.93" - Average rainfall in May:
2.56" - Average rainfall in June:
1.85"
The wettest month (with the highest rainfall) is May (2.56").
The driest month (with the least rainfall) is November (1.1").
Average rainfall days
Johnstown, PA
- Average rainfall days in January:
6.8 days - Average rainfall days in February:
7.2 days - Average rainfall days in March:
11.8 days - Average rainfall days in April:
15.3 days - Average rainfall days in May:
19.8 days - Average rainfall days in June:
16.7 days
- Average rainfall days in July:
16.7 days - Average rainfall days in August:
14.8 days - Average rainfall days in September:
13.5 days - Average rainfall days in October:
12.9 days - Average rainfall days in November:
7.8 days - Average rainfall days in December:
9.4 days
The month with the highest number of rainy days is May (19.8 days).
The month with the least rainy days is January (6.8 days).
Average snowfall
Johnstown, PA
- Average snowfall in January:
3.98" - Average snowfall in February:
4.09" - Average snowfall in March:
4.21" - Average snowfall in April:
0.83" - Average snowfall in May:
0.2" - Average snowfall in June:
0"
The month with the highest snowfall is March (4.21").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days
Johnstown, PA
- Average snowfall days in January:
12 days - Average snowfall days in February:
11.2 days - Average snowfall days in March:
8.2 days - Average snowfall days in April:
2.8 days - Average snowfall days in May:
0.4 days - Average snowfall days in June:
0 days
- Average snowfall days in July:
0 days - Average snowfall days in August:
0 days - Average snowfall days in September:
0 days - Average snowfall days in October:
0.9 days - Average snowfall days in November:
4.1 days - Average snowfall days in December:
8.1 days
The month with the highest number of snowfall days is January (12 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight / Average sunshine
Johnstown, PA
- Average daylight in January:
9h and 42min - Average daylight in February:
10h and 42min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 18min - Average daylight in May:
14h and 24min - Average daylight in June:
15h and 0min
- Average daylight in July:
14h and 42min - Average daylight in August:
13h and 42min - Average daylight in September:
12h and 24min - Average daylight in October:
11h and 6min - Average daylight in November:
10h and 0min - Average daylight in December:
9h and 24min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in January:
3h and 0min - Average sunshine in February:
3h and 24min - Average sunshine in March:
5h and 18min - Average sunshine in April:
7h and 30min - Average sunshine in May:
8h and 24min - Average sunshine in June:
9h and 12min
- Average sunshine in July:
9h and 48min - Average sunshine in August:
9h and 42min - Average sunshine in September:
8h and 12min - Average sunshine in October:
5h and 6min - Average sunshine in November:
4h and 54min - Average sunshine in December:
3h and 24min
The month with the most sunshine is July (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 0min).
Average sunshine days
Johnstown, PA
- Average sunshine days in January:
14.8 days - Average sunshine days in February:
12.2 days - Average sunshine days in March:
12.3 days - Average sunshine days in April:
11.1 days - Average sunshine days in May:
9 days - Average sunshine days in June:
11.4 days
- Average sunshine days in July:
11.6 days - Average sunshine days in August:
12.8 days - Average sunshine days in September:
13.9 days - Average sunshine days in October:
15.3 days - Average sunshine days in November:
18.8 days - Average sunshine days in December:
15.4 days
The month with the most sunshine days is November (18.8 days).
The month with the least sunshine days is May (9 days).
Average UV index
Johnstown, PA
The months with the highest UV index are May, June, July and August (UV index 5).
The month with the lowest UV index is December (UV index 1).
Average cloud cover
Johnstown, PA
The month with the most cloud cover is January (Cloud cover 72).
The month with the least cloud cover is August (Cloud cover 39).
Average visibility
Johnstown, PA
The month with the highest visibility is April (6mi).
The months with the lowest visibility are January, February, March, May, June, July, August, September, October, November and December (5mi).





