September weather forecast and climate
Yorklyn, DE

September, the first month of the autumn, in Yorklyn, is still a warm month, with average temperature fluctuating between 75.7°F (24.3°C) and 59.4°F (15.2°C).

Temperature

In September, the average high-temperature marginally drops, from a moderately hot 82.4°F (28°C) in August, to a still warm 75.7°F (24.3°C). The average low-temperature, in Yorklyn, is 59.4°F (15.2°C).

Humidity

The average relative humidity in Yorklyn is 78%.

Rainfall

In Yorklyn, during September, the rain falls for 11.2 days and regularly aggregates up to 1.1" (28mm) of precipitation. In Yorklyn, during the entire year, the rain falls for 135 days and collects up to 17.76" (451mm) of precipitation.

Snowfall

June through October are months without snowfall in Yorklyn.

Daylight

In Yorklyn, the average length of the day is 12.4h.

Sunshine

The average sunshine is 8.9h.

UV index

In September, the average daily maximum UV index is 4. A UV Index reading of 3 to 5 represents a medium vulnerability from unprotected exposure to the Sun's UV rays for the average person.
Note: The average daily UV index of 4 transform into the following instructions:
Take precautions - Protection against the skin and eye damage is obliged. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. 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.

What is the temperature in September in Yorklyn?

In September, in Yorklyn, Delaware, the average high-temperature is 75.7°F (24.3°C), and the average low-temperature is 59.4°F (15.2°C).

What is the average humidity in September in Yorklyn?

In Yorklyn, Delaware, the average relative humidity in September is 78%.

How much does it rain in Yorklyn in September?

In Yorklyn, during September, the rain falls for 11.2 days and regularly aggregates up to 1.1" (28mm) of precipitation.

When it does not snow in Yorklyn?

In Yorklyn, Delaware, snow does not fall in June through October.

How many hours of daylight does Yorklyn have in September?

In Yorklyn, Delaware, the average length of the day in September is 12.4h.

How long on average sun shines in September in Yorklyn?

The average sunshine in September in Yorklyn is 8.9h.

What is the UV index intensity in September in Yorklyn?

The average daily maximum UV index in September in Yorklyn, Delaware, is 4. A UV Index of 3 to 5 symbolizes a medium health risk from the exposure to the Sun's UV radiation.
Average temperature in September - Yorklyn, DE
  • Average high temperature in September: 75.7°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 (36.9°F).

  • Average low temperature in September: 59.4°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 (24.8°F).

Average pressure in September - Yorklyn, DE
  • Average pressure in September: 30.06"

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 September - Yorklyn, DE
  • Average wind speed in September: 5.8mph

The windiest months (with the highest average wind speed) are January, February and March (8.6mph).
The calmest months (with the lowest average wind speed) are July and August (5.3mph).

Average humidity in September - Yorklyn, DE
  • Average humidity in September: 78%

The month with the highest relative humidity is October (79%).
The month with the lowest relative humidity is April (74%).

Average rainfall in September - Yorklyn, DE
  • Average rainfall in September: 1.1"

The wettest month (with the highest rainfall) is August (2.36").
The driest month (with the least rainfall) is November (1.06").

Average rainfall days in September - Yorklyn, DE
  • Average rainfall days in September: 11.2 days

The month with the highest number of rainy days is July (15.8 days).
The month with the least rainy days is January (6.6 days).

Average snowfall in September - Yorklyn, DE
  • Average snowfall in September: 0"

The month with the highest snowfall is March (1.5").
Months with the least snowfall are June, July, August, September and October (0").

Average snowfall days in September - Yorklyn, DE
  • Average snowfall days in September: 0 days

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

Average daylight in September / Average sunshine in September - Yorklyn, DE
  • Average daylight in September: 12.4h

The month with the longest days is June (Average daylight: 15h).
The month with the shortest days is December (Average daylight: 9.4h).

  • Average sunshine in September: 8.9h

The month with the most sunshine is July (Average sunshine: 10.7h).
The month with the least sunshine is February (Average sunshine: 4.8h).

Average sunshine days in September - Yorklyn, DE
  • Average sunshine days in September: 16.7 days

The month with the most sunshine days is November (21 days).
The month with the least sunshine days is July (12.8 days).

Average UV index in September - Yorklyn, DE
  • Average UV index in September: 4

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 September - Yorklyn, DE
  • Average cloud cover in September: 38

Months with the most cloud cover are February, March and May (Cloud cover 47).
The month with the least cloud cover is July (Cloud cover 31).

Average visibility in September - Yorklyn, DE
  • Average visibility in September: 5mi

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