Climate and monthly weather forecastNew Castle, PA
Climate and monthly weather forecast
The climate of New Castle
A major characteristic of New Castle's weather is that it falls under the Koppen's Dfb climate classification, adding to the climatic diversity in Pennsylvania, USA. This classification attributes the locale to a Humid Continental zone with no dry season; the summers are warm and welcoming. The geographical location and this climate type together shape an intriguing weather pattern.A year-round temperature fluctuation prevails in New Castle with a maximum of 82°F (27.8°C) in July and a cold depth of 18.9°F (-7.3°C) in January. Humidity levels maintain consistency with little variation, averaging between 78 and 87% throughout the year. Precipitation similarly displays a consistent pattern, rainfall ranging from 2.24" (57mm) to 3.66" (93mm) from January to December. The city experiences snowy conditions with January and December witnessing the towering figures of 6.93" (176mm) and 4.69" (119mm) respectively.
Among the unique weather patterns of New Castle, July stands out for its warmth reaching up to 82°F (27.8°C), while January poses the challenging cold with its low temperature of 18.9°F (-7.3°C) and the highest snowfall of 6.93" (176mm). Another noteworthy element is December, which apart from its cold temperatures, experiences 2.68" (68mm) of rainfall, further intensifying the winter climate.
The best time to visit New Castle
A consensus among travelers and locals suggests that the period from June to August makes for the best time to visit New Castle. The city basks in decently high temperatures, hitting the maxima of 77.5°F (25.3°C) in June and 82°F (27.8°C) in July. Rainfall is also at its lowest levels during these months, ranging from 2.48" (63mm) to 3.35" (85mm). These months offer the longest daylight hours, peaking at 15.1 hours in June, and adequate sunshine, almost 9.9 hours in July, ensuring plenty of time to enjoy the local attractions. Additionally, the UV index is high at 6, calling for sun protection gear to maximize enjoyment.The worst time to visit New Castle
While adventure seekers may disagree, the stretch from December to February marks the most challenging time, weather-wise, in New Castle. Temperatures plummet to their lowest, with January bearing the cold brunt dipping to 18.9°F (-7.3°C). Snowfall also accompanies, with 6.93" (176mm) and 4.69" (119mm) in January and December, respectively, leading to harsh conditions for outdoor activity. Daylight hours are at a minimum, at 9.3 hours during December, and sunshine is scarce. Visitors would need to brave the elements to enjoy New Castle during these months.Spring weather in New Castle
Spring in New Castle commences with an average lowest temperature of 29.1°F (-1.6°C) in March, which improves to a pleasing 49.6°F (9.8°C) in May. This period sees an uptick in precipitation, with rainfall increasing from 2.76" (70mm) in March to 3.39" (86mm) in May. Surprisingly, snowfall starts disappearing with only 1.02" (26mm) in April and just an occasional 0.08" (2mm) in May.Summer weather in New Castle
Summer kicks off in June with temperatures reaching a balmy 77.5°F (25.3°C), with July being the warmest month at 82°F (27.8°C). The season is peppered with moderate rainfall, hovering between 3.35" (85mm) and 2.48" (63mm) from June to August, and humidity remains steady at 78%. This period not only allows ample daylight, peaking at 15.1 hours in June, but also provides an abundance of sunshine, with the highest at 9.9 hours in July.Autumn weather in New Castle
Autumn in New Castle brings a blend of cooling temperatures and increased precipitation. Temperatures start decreasing from 73.8°F (23.2°C) in September and fall to 33.1°F (0.6°C) in November. While October sees the highest rainfall of the season with 3.11" (79mm), light snowfall marks the onset of winter in November, with an occasional 2.83" (72mm). Despite this, the season offers considerable daylight- between 12.5 hours and 9.9 hours, accompanied by a reasonable amount of sunshine, 8.2 hours in September, dwindling down to 4.5 hours by November.Winter weather in New Castle
Winter can be challenging in New Castle with temperatures hitting the year's lowest at 18.9°F (-7.3°C) in January, and never going beyond 38.1°F (3.4°C) in December. This season witnesses some of the heaviest snowfall, amounting to 6.93" (176mm) in January. December sees the year’s second-highest precipitation at 2.68" (68mm). Despite the daylight being limited to an average of 9.3 hours in December, the season can provide unique experiences for visitors who enjoy the winter chill.Weather in January
Amidst the harsh winters of New Castle, Pennsylvania, January stands out with the highest relative humidity of 86%. Snowfall is a common phenomenon, covering the city in a mantle of white that contrasts beautifully with the frequent, overcast skies. Weather in January »Weather in February
The grey, wintry landscape of New Castle continues into February, with temperatures that are only slightly warmer than January. The average low temperature remains likely below freezing, though marginally higher from 18.9°F (-7.3°C) witnessed in January to February's 20.7°F (-6.3°C). Weather in February »Weather in March
March heralds the arrival of spring in New Castle, symbolizing a noticeable change in climatic conditions. Temperatures experience a substantial lift from the hard winter lows, breathing life into the frozen vegetation. Rainfall begins to edge ahead of snowfall, offering a respite from the relentless white landscape. Weather in March »Weather in April
April sees a significant shift in weather patterns in New Castle, marking the end of the long winter spell. The coldest temperatures increase by almost 10°F (-12.2°C) from 29.1°F (-1.6°C) in March to 39.2°F (4°C) in April. This month brings a surge in day length and sunlight exposure, uplifting the spirits of the city's inhabitants. Weather in April »Weather in May
With the advent of May, New Castle witnesses a noteworthy upsurge in temperatures. The transition from spring to early summer is marked by blossoming flowers and the chirping of birds returning after the winter. Rainfall continues to be a vital part of the weather equation, imparting a refreshing change to the atmosphere. Weather in May »Weather in June
The climatic conditions of New Castle in June indicate the steady approach of summer. While it doesn't get as hot as other areas, the warmest average temperature increases slightly to 77.5°F (25.3°C). The increased hours of daylight illuminate the city for longer periods, providing ample opportunities for outdoor adventures. Weather in June »Weather in July
July is the zenith of summer in New Castle, Pennsylvania, characterized by warm temperatures, sunny skies, and a cheerful ambience. These summer conditions peak with the highest average temperature registering at 82°F (27.8°C). The combination of reduced cloud cover and ample sunlight make this the ideal month for outdoor adventures, lake visits, and barbecues. Weather in July »Weather in August
August brings a subtle decrease in temperature, signaling the nearing end of summer. While the descent from July's peak of 82°F (27.8°C) to 80.6°F (27°C) in this month is only slight, it indicates the gradual transition to the cooler months. Weather in August »Weather in September
New Castle in September is a spectacle of vibrant fall colours, mild temperatures, and captivating beauty. Average temperatures take a dip from the 80.6°F (27°C) seen in August to a more comfortable 73.8°F (23.2°C). The shorter days and longer nights signal the beginning of fall and the end of summer fun. Weather in September »Weather in October
October sees a further drop in temperature as autumn firmly establishes its presence in New Castle. Among the notable changes, the climb down from September's 73.8°F (23.2°C) to 60.4°F (15.8°C) stands out. The fall season is in full swing, with spectacular displays of colorful foliage adorning the cityscape. Weather in October »Weather in November
November in New Castle, Pennsylvania brings colder temperatures and the first signs of the impending winter. The noticeable reduction from an average high of 60.4°F (15.8°C) in October to 47.7°F (8.7°C) in this month is a strong indication of the transition. Weather in November »Weather in December
The arrival of December symbolizes the onset of winter in New Castle, which is marked by chilly temperatures, minimal daylight, and increased snowfall. The disparity in December's average high temperature from November's 47.7°F (8.7°C) to a much colder 38.1°F (3.4°C), reinforces the arrival of the frosty season. Weather in December »Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature
New Castle, PA
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (31.5°F).
The month with the highest average low temperature is July (60.8°F).
The coldest month (with the lowest average low temperature) is January (18.9°F).
Average pressure
New Castle, PA
- Average pressure in January:
30.1"Hg - Average pressure in February:
30.08"Hg - Average pressure in March:
30.09"Hg - Average pressure in April:
29.97"Hg - Average pressure in May:
29.99"Hg - Average pressure in June:
29.94"Hg
- Average pressure in July:
29.97"Hg - Average pressure in August:
29.99"Hg - Average pressure in September:
30.05"Hg - Average pressure in October:
30.03"Hg - Average pressure in November:
30.12"Hg - Average pressure in December:
30.1"Hg
The month with the highest atmospheric pressure is November (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed
New Castle, PA
- Average wind speed in January:
8.3mph - Average wind speed in February:
7.8mph - Average wind speed in March:
7.6mph - Average wind speed in April:
7.7mph - Average wind speed in May:
6.4mph - Average wind speed in June:
5.9mph
- Average wind speed in July:
5.1mph - Average wind speed in August:
5.2mph - Average wind speed in September:
5.6mph - Average wind speed in October:
6.8mph - Average wind speed in November:
7.3mph - Average wind speed in December:
7.6mph
The windiest month (with the highest average wind speed) is January (8.3mph).
The calmest month (with the lowest average wind speed) is July (5.1mph).
Average humidity
New Castle, PA
The month with the highest relative humidity is February (87%).
The months with the lowest relative humidity are April, May, June, July and August (78%).
Average rainfall
New Castle, PA
- Average rainfall in January:
2.64" - Average rainfall in February:
2.6" - Average rainfall in March:
2.76" - Average rainfall in April:
3.54" - Average rainfall in May:
3.39" - Average rainfall in June:
3.66"
- Average rainfall in July:
3.35" - Average rainfall in August:
2.48" - Average rainfall in September:
2.48" - Average rainfall in October:
3.11" - Average rainfall in November:
2.24" - Average rainfall in December:
2.68"
The wettest month (with the highest rainfall) is June (3.66").
The driest month (with the least rainfall) is November (2.24").
Average rainfall days
New Castle, PA
- Average rainfall days in January:
8.8 days - Average rainfall days in February:
10.3 days - Average rainfall days in March:
13.7 days - Average rainfall days in April:
17.5 days - Average rainfall days in May:
19.3 days - Average rainfall days in June:
17.9 days
- Average rainfall days in July:
18.6 days - Average rainfall days in August:
16.3 days - Average rainfall days in September:
15.1 days - Average rainfall days in October:
16.5 days - Average rainfall days in November:
11.6 days - Average rainfall days in December:
12 days
The month with the highest number of rainy days is May (19.3 days).
The month with the least rainy days is January (8.8 days).
Average snowfall
New Castle, PA
- Average snowfall in January:
6.93" - Average snowfall in February:
6.02" - Average snowfall in March:
3.5" - Average snowfall in April:
1.02" - Average snowfall in May:
0.08" - Average snowfall in June:
0"
The month with the highest snowfall is January (6.93").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days
New Castle, PA
- Average snowfall days in January:
18.6 days - Average snowfall days in February:
15.9 days - Average snowfall days in March:
9.6 days - Average snowfall days in April:
3.2 days - Average snowfall days in May:
0.3 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:
0.3 days - Average snowfall days in November:
6 days - Average snowfall days in December:
14.3 days
The month with the highest number of snowfall days is January (18.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight / Average sunshine
New Castle, PA
- Average daylight in January:
9h and 36min - 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 30min - Average daylight in June:
15h and 6min
- Average daylight in July:
14h and 48min - Average daylight in August:
13h and 48min - Average daylight in September:
12h and 30min - Average daylight in October:
11h and 6min - Average daylight in November:
9h and 54min - Average daylight in December:
9h and 18min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in January:
2h and 30min - Average sunshine in February:
3h and 6min - Average sunshine in March:
5h and 0min - Average sunshine in April:
7h and 6min - Average sunshine in May:
8h and 30min - Average sunshine in June:
9h and 6min
- Average sunshine in July:
9h and 54min - Average sunshine in August:
10h and 0min - Average sunshine in September:
8h and 12min - Average sunshine in October:
4h and 54min - Average sunshine in November:
4h and 30min - Average sunshine in December:
3h and 0min
The month with the most sunshine is August (Average sunshine: 10h and 0min).
The month with the least sunshine is January (Average sunshine: 2h and 30min).
Average sunshine days
New Castle, PA
- Average sunshine days in January:
7.7 days - Average sunshine days in February:
7 days - Average sunshine days in March:
10.3 days - Average sunshine days in April:
9.8 days - Average sunshine days in May:
9.8 days - Average sunshine days in June:
9.8 days
- Average sunshine days in July:
10.5 days - Average sunshine days in August:
12.8 days - Average sunshine days in September:
13.1 days - Average sunshine days in October:
12.6 days - Average sunshine days in November:
13.5 days - Average sunshine days in December:
9.4 days
The month with the most sunshine days is November (13.5 days).
The month with the least sunshine days is February (7 days).
Average UV index
New Castle, PA
The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover
New Castle, PA
The month with the most cloud cover is January (Cloud cover 73).
The month with the least cloud cover is August (Cloud cover 36).
Average visibility
New Castle, PA
The month with the highest visibility is April (6mi).
The months with the lowest visibility are January, February and December (4mi).





