January weather forecast and climate
New Castle, DE

January, the same as December, is a wintry winter month in New Castle, Delaware, with average temperature fluctuating between 37.8°F (3.2°C) and 26.1°F (-3.3°C).

Temperature

With an average high-temperature of 37.8°F (3.2°C) and an average low-temperature of 26.1°F (-3.3°C), January is the coldest month.

Humidity

The average relative humidity in January is 74%.

Rainfall

The month with the least rainfall in New Castle, Delaware, is January when the rain falls for 7.8 days and typically collects 1.38" (35mm) of precipitation.

Snowfall

January through April, November and December are months with snowfall in New Castle. January is the month with the most snowfall in New Castle. Snow falls for 5.2 days and accumulates 1.69" (43mm) of snow.

Ocean temperature

In New Castle, Delaware, in January, the average water temperature is 42.4°F (5.8°C).
Note: Swimming in 42.4°F (5.8°C) is considered dangerous. Unprotected immersion in temperatures below 50°F (10°C) causes quickly maximum intensity cold shock with hyperventilation.

Daylight

In New Castle, Delaware, the average length of the day in January is 9.7h.

Sunshine

The average sunshine in New Castle is 5.1h.

UV index

Months with the lowest UV index in New Castle, Delaware, are January, February, November and December, with an average maximum UV index of 2. A UV Index estimate of 2, and below, represents a low threat to health from unprotected exposure to the Sun's UV rays for average individuals.
Note: The average daily UV index of 2 in January transform into the following instructions:
Most people can stay in the Sun for up to 1 hour without burning, apart from children that always must be protected from sun exposure. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects. Beware! The strength of the UV rays is increased nearly double-fold by the reflection of the snow.

What is the coldest month in New Castle?

January is the coldest month in New Castle, with an average high-temperature of 37.8°F (3.2°C) and an average low-temperature of 26.1°F (-3.3°C).

What is the temperature in January in New Castle?

The average high-temperature, in January, in New Castle, Delaware, is 37.8°F (3.2°C), while the average low-temperature is 26.1°F (-3.3°C).

What is the average humidity in January in New Castle?

The average relative humidity in January is 74%.

How many days does it rain in January in New Castle?

In New Castle, in January, it is raining for 7.8 days, with typically 1.38" (35mm) of accumulated precipitation.

What is the driest month in New Castle?

January is the month with the least rainfall in New Castle. Rain falls for 7.8 days and accumulates 1.38" (35mm) of precipitation.

How many days does it snow in January in New Castle?

In January, in New Castle, it is snowing for 5.2 days. Throughout January, 1.69" (43mm) of snow is accumulated.

What is the snowiest month in New Castle?

The month with the most snowfall in New Castle is January when snow falls for 5.2 days and typically aggregates up to 1.69" (43mm) of snow.

How cold is the water in January in New Castle?

In January, the average ocean temperature in New Castle, Delaware, is 42.4°F (5.8°C). Swimming in 42.4°F (5.8°C) is considered life-threatening. Even a few minutes in 55.4°F (13°C) water is uncomfortable, and swimming below 50°F (10°C) may cause total loss of breathing control and cold shock, depending on a person's physique.

What is the average length of the day in January in New Castle?

In New Castle, the average length of the day in January is 9.7h.

How long on average sun shines in January in New Castle?

In January, the average sunshine in New Castle, Delaware, is 5.1h.

What are the months with the lowest UV index in New Castle?

Months with the lowest UV index are January, February, November and December, with an average maximum UV index of 2.

What is the UV index reading in January in New Castle?

The average daily maximum UV index in January in New Castle is 2. A UV Index estimate of 2, and below, represents a minimal hazard to health from unprotected exposure to the UV radiation.
Average temperature in January - New Castle, DE
  • Average high temperature in January: 37.8°F

The warmest month (with the highest average high temperature) is July (84.9°F).
The month with the lowest average high temperature is January (37.8°F).

  • Average low temperature in January: 26.1°F

The month with the highest average low temperature is July (68.5°F).
The coldest month (with the lowest average low temperature) is January (26.1°F).

Average pressure in January - New Castle, DE
  • Average pressure in January: 30.09"

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

Average wind speed in January - New Castle, DE
  • Average wind speed in January: 8.7mph

The windiest months (with the highest average wind speed) are February and March (8.8mph).
The calmest month (with the lowest average wind speed) is August (5.4mph).

Average humidity in January - New Castle, DE
  • Average humidity in January: 74%

The month with the highest relative humidity is October (78%).
The month with the lowest relative humidity is April (72%).

Average rainfall in January - New Castle, DE
  • Average rainfall in January: 1.38"

The wettest month (with the highest rainfall) is August (2.83").
The driest month (with the least rainfall) is January (1.38").

Average rainfall days in January - New Castle, DE
  • Average rainfall days in January: 7.8 days

The month with the highest number of rainy days is May (16.8 days).
The month with the least rainy days is January (7.8 days).

Average snowfall in January - New Castle, DE
  • Average snowfall in January: 1.69"

The month with the highest snowfall is January (1.69").
Months with the least snowfall are May, June, July, August, September and October (0").

Average snowfall days in January - New Castle, DE
  • Average snowfall days in January: 5.2 days

The month with the highest number of snowfall days is January (5.2 days).
Months with the least snowfall days are May, June, July, August, September and October (0 days).

Average sea temperature in January - New Castle, DE
  • Average sea temperature in January: 42.4°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 January / Average sunshine in January - New Castle, DE
  • Average daylight in January: 9.7h

The month with the longest days is June (Average daylight: 14.9h).
The month with the shortest days is December (Average daylight: 9.4h).

  • Average sunshine in January: 5.1h

The month with the most sunshine is July (Average sunshine: 10.8h).
The month with the least sunshine is February (Average sunshine: 4.9h).

Average sunshine days in January - New Castle, DE
  • Average sunshine days in January: 19.3 days

The month with the most sunshine days is November (20.1 days).
The month with the least sunshine days is May (11.8 days).

Average UV index in January - New Castle, DE
  • Average UV index in January: 2

Months with the highest UV index are May, June, July and August (UV index 6).
Months with the lowest UV index are January, February, November and December (UV index 2).

Average cloud cover in January - New Castle, DE
  • Average cloud cover in January: 44

Months with the most cloud cover are February and March (Cloud cover 46).
The month with the least cloud cover is July (Cloud cover 30).

Average visibility in January - New Castle, DE
  • Average visibility in January: 6mi

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