Climate and monthly weather forecastManassas, VA
Climate and monthly weather forecast
The climate of Manassas
Manassas, Virginia, USA, falls under the classification Cfa of the Köppen Climate System. This signifies a humid subtropical climate, where no dry season prevails. Geographically located in the Northern Hemisphere, Manassas experiences a spread of climate conditions across the year.On an average, the temperature in Manassas ranges from a high of 40.6°F (4.8°C) in January to 88.3°F (31.3°C) in July, and a low between 26.4°F (-3.1°C) in January to 67.1°F (19.5°C) in July. This signifies a significant variation in temperature across the months. In terms of humidity, the region experiences a fairly steady relative humidity throughout the year, oscillating between 72% and 78%.
The yearly rainfall spans from 1.93" (49mm) in September to the peak at 3.43" (87mm) during August. With 9.3 days of rain in November to 17.4 days in May, the city experiences a wide range of wet days throughout the year. Snowfall remains absent from May to September, peaking in January at 3.7" (94mm) and falling over 4.9 days, while daylight hours widen from 9.8 hours in January to 14.8 hours in June.
The best time to visit Manassas
June through August present the warmest weather conditions in Manassas, making these months an optimal time for outdoor activities. July presents the highest temperature, touching an average high of 88.3°F (31.3°C), while the lowest humidity of the year is recorded in these months. Furthermore, the city enjoys maximum daylight hours, particularly in June, with an average of 14.8 hours in a day.The worst time to visit Manassas
The months between December and February can be challenging for visitors due to the relatively colder weather. January records the lowest temperatures, with an average high of 40.6°F (4.8°C) and an average low of 26.4°F (-3.1°C). Moreover, these months register the maximum snowfall, reaching 3.7" (94mm) in January, and the shortest days, counting only 9.5 daylight hours in December.Spring weather in Manassas
From March to May, the weather in Manassas shifts towards warmer conditions. The average high temperature increases progressively from 53.2°F (11.8°C) in March to 75.4°F (24.1°C) in May. This is accompanied by an increase in rainfall, which accumulates from 2.48" (63mm) in March to 3.11" (79mm) in May.Summer weather in Manassas
During summer, from June to August, the weather in Manassas becomes impressively warm. The temperature reaches its peak in July with an average high of 88.3°F (31.3°C). In terms of rainfall, August receives the most at an average of 3.43" (87mm).Autumn weather in Manassas
Autumn in Manassas, from September to November, witnesses a drop in temperatures. The average high temperature decreases dramatically from 79°F (26.1°C) in September to 54.5°F (12.5°C) in November. The rainfall also shows a downward trend during this period, reducing to an average of 2.2" (56mm) in November.Winter weather in Manassas
Winter in Manassas spans from December to February. The average high temperature stays between 40.6°F (4.8°C) and 45.7°F (7.6°C), while the average low temperature drops from 32.4°F (0.2°C) to 26.4°F (-3.1°C). Snowfall increases during these months, with January recording the highest snowfall of 3.7" (94mm).Weather in January
Entering the year with January, Manassas weather grapples with notable cold temperatures. The daily thermometers indicate a typical swing from 40.6°F (4.8°C) to 26.4°F (-3.1°C). Sunlight remains scarce with significantly short days and a cloud cover that seems to persistently hang over the city. Weather in January »Weather in February
Moving into February, even as winter holds its grip over Manassas, the city witnesses a slight rise in average temperatures. A predominant characteristic of this month's weather is a slight increase in daylight hours, bringing an additional hour of sunlight compared to January. Weather in February »Weather in March
In March, Manassas begins to transition from winter to spring, with temperatures that climb steadily from February’s chill. With the temperature high breaking the 50°F (10°C) barrier and snow nearly disappearing, just 2.64" (67mm) recorded for the month, the winter chill begins to recede. Weather in March »Weather in April
April graces Manassas with a definitive shift towards milder spring temperatures. The evident warm-up brings the average high up to a more comfortable 65.7°F (18.7°C). Simultaneously, Manassas residents see a considerable reduction in the average cloud cover compared to the preceding winter months. Weather in April »Weather in May
By the time May arrives in Manassas, the city is deeply entrenched in the throes of spring. With temperatures averaging between 75.4°F (24.1°C) and 55.2°F (12.9°C), it is noticeably warmer than the previous month. The city sees an enduring stretch of longer daylight hours and decreasing cloud cover. Weather in May »Weather in June
June signals the onset of summer in Manassas, with sharp spikes in temperature making this month noticeably hotter than May. Warmer temperatures between 83.7°F (28.7°C) and 62.8°F (17.1°C) mark the hottest days of the year so far. Weather in June »Weather in July
July in Manassas is characterized by sweltering summer temperatures, making it the hottest month of the year. The temperature high blazes at 88.3°F (31.3°C), and nights provide little relief, with the low barely dipping below 67.1°F (19.5°C). Weather in July »Weather in August
August weather conditions in Manassas remain notably similar to July. Average high temperatures slightly lower from the July high, hitting 85.8°F (29.9°C). Rainfall in the city bumps up, with precipitation reaching the peak volume of the year. Weather in August »Weather in September
September sees Manassas transitioning into autumn, with gradual cooling temperatures painting a stark contrast to the preceding summer months. The city oversees a notable drop in the average high temperature, descending to 79°F (26.1°C). Weather in September »Weather in October
Entering October, Manassas experiences a further stride into fall conditions. With a noticeable decline from September's fees, the average high temperature hovers around a much cooler 67.1°F (19.5°C). As the cloud cover that characterized earlier months dissipates, the city enjoys clearer skies and the accompanying autumn sunshine. Weather in October »Weather in November
As the city ushers in November, the weather in Manassas steadily trends toward winter conditions. With thermometers indicating a downswing to a much colder average high of 54.5°F (12.5°C), the residents prepare for winter's imminent arrival. Weather in November »Weather in December
December in Manassas brings the full force of winter, with temperatures predominantly dwelling between the monthly high of 45.7°F (7.6°C) and the low of 32.4°F (0.2°C). The month distinguishes itself as the first of the season to record more than an inch of snowfall, indicating a 1.61-inch accumulation. Weather in December »Updated: Feb 14, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
January proves to be the coldest month, recording an average maximum temperature of 40.6°F (4.8°C) and a minimum temperature of 26.4°F (-3.1°C).
Throughout the year, in Manassas, Virginia, there are 157.5 rainfall days, and 30.35" (771mm) of precipitation is accumulated.
Months with snowfall are January through April, November and December.
The month with the most snowfall is January, when snow falls for 4.9 days and typically aggregates up to 3.7" (94mm) of snow.
In Manassas, Virginia, during the entire year, snow falls for 15.8 days and aggregates up to 11.5" (292mm) of snow.
January, February and December, with an average of 5.2h of sunshine, are months with the least sunshine in Manassas.
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index.
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts in Manassas, and the time zone changes from EST to EDT. Daylight Saving Time ends Sunday, November 3. 2024, at 2:00 am, and the time zone reverts from EDT to EST.
May through October are months without snowfall in Manassas, Virginia.
May through August, with an average maximum UV index of 6, are months with the highest UV index.
The month with the longest days in Manassas is June, with an average of 14h and 48min of daylight.
July, having an average high-temperature of 88.3°F (31.3°C) and an average low-temperature of 67.1°F (19.5°C), is the warmest month in Manassas.
July is the least humid month, with an average relative humidity of 72%.
July has the most sunshine of the year in Manassas, Virginia, with an average of 10.7h of sunshine.
The month with the most rainfall is August, when the rain falls for 16.3 days and typically aggregates up to 3.43" (87mm) of precipitation.
The month with the least rainfall is September, when the rain falls for 12.7 days and typically collects 1.93" (49mm) of precipitation.
With an average relative humidity of 78%, December is the most humid month in Manassas.
The month with the shortest days in Manassas, Virginia, is December, with an average of 9h and 30min of daylight.
Average temperature
Manassas, VA
The warmest month (with the highest average high temperature) is July (88.3°F).
The month with the lowest average high temperature is January (40.6°F).
The month with the highest average low temperature is July (67.1°F).
The coldest month (with the lowest average low temperature) is January (26.4°F).
Average pressure
Manassas, VA
- 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:
29.99"Hg - Average pressure in May:
30.01"Hg - Average pressure in June:
29.95"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:
30.04"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
Manassas, VA
- Average wind speed in January:
6.5mph - Average wind speed in February:
6.6mph - Average wind speed in March:
7mph - Average wind speed in April:
7mph - Average wind speed in May:
5.8mph - Average wind speed in June:
5.3mph
- Average wind speed in July:
4.7mph - Average wind speed in August:
4.6mph - Average wind speed in September:
5.1mph - Average wind speed in October:
5.9mph - Average wind speed in November:
6mph - Average wind speed in December:
6mph
The windiest months (with the highest average wind speed) are March and April (7mph).
The calmest month (with the lowest average wind speed) is August (4.6mph).
Average humidity
Manassas, VA
The month with the highest relative humidity is December (78%).
The month with the lowest relative humidity is July (72%).
Average rainfall
Manassas, VA
- Average rainfall in January:
1.97" - Average rainfall in February:
2.01" - Average rainfall in March:
2.48" - Average rainfall in April:
2.87" - Average rainfall in May:
3.11" - Average rainfall in June:
2.64"
- Average rainfall in July:
2.68" - Average rainfall in August:
3.43" - Average rainfall in September:
1.93" - Average rainfall in October:
2.48" - Average rainfall in November:
2.2" - Average rainfall in December:
2.56"
The wettest month (with the highest rainfall) is August (3.43").
The driest month (with the least rainfall) is September (1.93").
Average rainfall days
Manassas, VA
- Average rainfall days in January:
9.5 days - Average rainfall days in February:
10.6 days - Average rainfall days in March:
13.8 days - Average rainfall days in April:
15.7 days - Average rainfall days in May:
17.4 days - Average rainfall days in June:
14.3 days
- Average rainfall days in July:
15.8 days - Average rainfall days in August:
16.3 days - Average rainfall days in September:
12.7 days - Average rainfall days in October:
11.8 days - Average rainfall days in November:
9.3 days - Average rainfall days in December:
10.3 days
The month with the highest number of rainy days is May (17.4 days).
The month with the least rainy days is November (9.3 days).
Average snowfall
Manassas, VA
The month with the highest snowfall is January (3.7").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days
Manassas, VA
- Average snowfall days in January:
4.9 days - Average snowfall days in February:
5.2 days - Average snowfall days in March:
2.5 days - Average snowfall days in April:
0.3 days - Average snowfall days in May:
0 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 days - Average snowfall days in November:
0.4 days - Average snowfall days in December:
2.5 days
The month with the highest number of snowfall days is February (5.2 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight / Average sunshine
Manassas, VA
- Average daylight in January:
9h and 48min - Average daylight in February:
10h and 48min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 12min - Average daylight in May:
14h and 18min - Average daylight in June:
14h and 48min
- Average daylight in July:
14h and 36min - Average daylight in August:
13h and 36min - Average daylight in September:
12h and 24min - Average daylight in October:
11h and 12min - Average daylight in November:
10h and 6min - Average daylight in December:
9h and 30min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in January:
5h and 12min - Average sunshine in February:
5h and 12min - Average sunshine in March:
6h and 48min - Average sunshine in April:
9h and 0min - Average sunshine in May:
8h and 54min - Average sunshine in June:
10h and 18min
- Average sunshine in July:
10h and 42min - Average sunshine in August:
10h and 6min - Average sunshine in September:
8h and 42min - Average sunshine in October:
5h and 36min - Average sunshine in November:
5h and 48min - Average sunshine in December:
5h and 12min
The month with the most sunshine is July (Average sunshine: 10h and 42min).
The months with the least sunshine are January, February and December (Average sunshine: 5h and 12min).
Average sunshine days
Manassas, VA
- Average sunshine days in January:
17.8 days - Average sunshine days in February:
14.8 days - Average sunshine days in March:
14.5 days - Average sunshine days in April:
12.9 days - Average sunshine days in May:
11.7 days - Average sunshine days in June:
13.9 days
- Average sunshine days in July:
12.2 days - Average sunshine days in August:
13 days - Average sunshine days in September:
15.9 days - Average sunshine days in October:
17.7 days - Average sunshine days in November:
19.8 days - Average sunshine days in December:
17.3 days
The month with the most sunshine days is November (19.8 days).
The month with the least sunshine days is May (11.7 days).
Average UV index
Manassas, VA
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover
Manassas, VA
The month with the most cloud cover is March (Cloud cover 47).
The month with the least cloud cover is July (Cloud cover 31).
Average visibility
Manassas, VA
The months with the highest visibility are January, February, March, April, June, July, August and November (6mi).
The months with the lowest visibility are May, September, October and December (5mi).
