May weather forecast
Charlestown, MD

Share

Weather in May

The last month of the spring, May, is an agreeable month in Charlestown, Maryland, with temperature in the range of an average low of 54.5°F (12.5°C) and an average high of 71.6°F (22°C).

Temperature

An upsurge in temperatures occurs as April gives way to May, with average highs shifting from an enjoyable 61.9°F (16.6°C) to an agreeable 71.6°F (22°C). Charlestown encounters an average low-temperature of 54.5°F (12.5°C) during May nights.

Humidity

The months with the highest humidity in Charlestown, Maryland, are May and June, with an average relative humidity of 79%.

Rainfall

In Charlestown, Maryland, in May, during 17.4 rainfall days, 2.68" (68mm) of precipitation is typically accumulated. In Charlestown, Maryland, during the entire year, the rain falls for 150.3 days and collects up to 29.25" (743mm) of precipitation.

Snowfall

Months with snowfall are January through March, May, November and December. May is the first month it typically snows in Charlestown. Throughout May, in the average 0.1 snowfall days, it receives 0.08" (2mm) of snow. Throughout the year, there are 13.1 snowfall days, and 6.89" (175mm) of snow is accumulated.

Ocean temperature

In Charlestown, Maryland, in May, the average water temperature is 54°F (12.2°C).
Note: Unprotected swimming in 54°F (12.2°C) is dangerous due to potential cold shock. Especially when temperatures go below 50°F (10°C), leading to hyperventilation.

Daylight

In May, the average length of the day is 14h and 22min.
On the first day of the month, sunrise is at 6:03 am and sunset at 7:58 pm. On the last day of May, in Charlestown, sunrise is at 5:38 am and sunset at 8:25 pm EDT.

Sunshine

In Charlestown, Maryland, the average sunshine in May is 8.6h.

UV index

The months with the highest UV index in Charlestown are May through August, with an average maximum UV index of 6. A UV Index value of 6 to 7 symbolizes a high health vulnerability from unsafe exposure to UV radiation for average individuals.
Note: The maximum UV index, 6 during May, leads to the following recommendations:
Uphold preventive measures and conform to sun safety guidelines. Defending against skin and eye harm is crucial. Avoid direct exposure to the Sun between 10 a.m. and 4 p.m., the peak period for UV radiation, noting that objects like parasols or canopies might not offer complete sun protection. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays. Pay attention! The reflection of snow can enhance the Sun's UV radiation almost double.
Updated: Feb 12, 2024 | Published by: Weather U.S. | About Us / Weather Forecasting / Data Sources

Frequently asked questions

What is the average May temperature in Charlestown?

May temperatures in Charlestown, Maryland, vary between a high-temperature of 71.6°F (22°C) and a low-temperature of 54.5°F (12.5°C).

What are the most humid months in Charlestown?

The months with the highest humidity in Charlestown are May and June, with an average relative humidity of 79%.

What is the average humidity in May in Charlestown?

The average relative humidity in May in Charlestown, Maryland, is 79%.

How much does it rain in Charlestown in May?

In Charlestown, in May, during 17.4 rainfall days, 2.68" (68mm) of precipitation is typically accumulated.

When does it start snowing in Charlestown?

May is the first month it typically snows. Throughout May, in the average 0.1 snowfall days, it receives 0.08" (2mm) of snow.

What is the ocean temperature in May in Charlestown?

In Charlestown, Maryland, the average seawater temperature in May is 54°F (12.2°C). At temperatures below 50°F (10°C), swimming in a suitably protected swimsuit is feasible; otherwise, cold shock and loss of breathing control are imminent. Even a short swim, without thermal protection, at temperatures around 55.4°F (13°C) is not comfortable.

How many hours of daylight does Charlestown have in May?

In Charlestown, the average day length in May is 14h and 22min.

When is the sunrise / sunset in May in Charlestown?

On the first day of May in Charlestown, sunrise is at 6:03 am and sunset at 7:58 pm. On the last day of the month, sunrise is at 5:38 am and sunset at 8:25 pm EDT.

How many hours of sunshine does Charlestown have in May?

In Charlestown, Maryland, the average sunshine duration in May is 8.6h.

What is the month with the highest UV index in Charlestown?

The months with the highest UV index are May through August, with an average maximum UV index of 6.

How high is the UV index in May in Charlestown?

The average daily maximum UV index in May is 6. A UV Index reading of 6 to 7 represents a high health vulnerability from unsafe exposure to Sun's UV rays.
Average humidity
Average rainfall days
Average snowfall
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in May
Charlestown, MD

Average temperature in May - Charlestown, MD
  • Average high temperature in May: 71.6°F

The warmest month (with the highest average high temperature) is July (84.7°F).
The month with the lowest average high temperature is January (37.9°F).

  • Average low temperature in May: 54.5°F

The month with the highest average low temperature is July (67.6°F).
The coldest month (with the lowest average low temperature) is January (26.1°F).

Average pressure in May
Charlestown, MD

Average pressure in May - Charlestown, MD
  • Average pressure in May: 30.01"Hg

The month with the highest atmospheric pressure is November (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).

Average wind speed in May
Charlestown, MD

Average wind speed in May - Charlestown, MD
  • Average wind speed in May: 6.9mph

The windiest months (with the highest average wind speed) are February and March (8.9mph).
The calmest month (with the lowest average wind speed) is August (5.3mph).

Average humidity in May
Charlestown, MD

Average humidity in May - Charlestown, MD
  • Average humidity in May: 79%

The months with the highest relative humidity are May and June (79%).
The month with the lowest relative humidity is April (74%).

Average rainfall in May
Charlestown, MD

Average rainfall in May - Charlestown, MD
  • Average rainfall in May: 2.68"

The wettest month (with the highest rainfall) is August (3.86").
The driest month (with the least rainfall) is January (1.85").

Average rainfall days in May
Charlestown, MD

Average rainfall days in May - Charlestown, MD
  • Average rainfall days in May: 17.4 days

The month with the highest number of rainy days is May (17.4 days).
The month with the least rainy days is January (7.8 days).

Average snowfall in May
Charlestown, MD

Average snowfall in May - Charlestown, MD
  • Average snowfall in May: 0.08"

The month with the highest snowfall is January (2.24").
The months with the least snowfall are April, June, July, August, September and October (0").

Average snowfall days in May
Charlestown, MD

Average snowfall days in May - Charlestown, MD
  • Average snowfall days in May: 0.1 days

The month with the highest number of snowfall days is January (4.4 days).
The months with the least snowfall days are April, June, July, August, September and October (0 days).

Average sea temperature in May
Charlestown, MD

Average sea temperature in May - Charlestown, MD
  • Average sea temperature in May: 53.9°F

The best month for swimming (with the highest average sea temperature) is August (76.3°F).
The coldest month (with the lowest average sea temperature) is February (40.9°F).

Average daylight in May /
Average sunshine in May
Charlestown, MD

Average daylight in May / Average sunshine in May - Charlestown, MD
  • Average daylight in May: 14h and 2min

The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 24min).

  • Average sunshine in May: 8h and 4min

The month with the most sunshine is July (Average sunshine: 10h and 42min).
The month with the least sunshine is February (Average sunshine: 4h and 54min).

Average sunshine days in May
Charlestown, MD

Average sunshine days in May - Charlestown, MD
  • Average sunshine days in May: 11.7 days

The month with the most sunshine days is November (20.4 days).
The month with the least sunshine days is July (11.6 days).

Average UV index in May
Charlestown, MD

Average UV index in May - Charlestown, MD
  • Average UV index in May: 6

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 in May
Charlestown, MD

Average cloud cover in May - Charlestown, MD
  • Average cloud cover in May: 45

The months with the most cloud cover are February and March (Cloud cover 46).
The month with the least cloud cover is July (Cloud cover 31).

Average visibility in May
Charlestown, MD

Average visibility in May - Charlestown, MD
  • Average visibility in May: 5mi

The months with the highest visibility are January, February, March, April, June, July, August, October, November and December (6mi).
The months with the lowest visibility are May and September (5mi).

Charlestown, Maryland, USA

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location