September weather forecast
Ellicott City, MD

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Weather in September

September marks the transition from summer to fall in Ellicott City. It brings a gradual drop in temperature with highs around 76.8°F (24.9°C), initiating a cooling trend over the coming months. The rains retreat drastically bringing a significant decrease in monthly rainfall to only 2.17" (55mm). September punctuates its late summer afternoons with serene, mildly cool evenings that are typical of an upcoming fall season. As September ends, October arrives, fully dressed in autumn attire.

Temperature

A mild shift in the average high-temperature occurs in September, reducing from 83.5°F (28.6°C) in August to a still moderately hot 76.8°F (24.9°C). An average low-temperature of 60.4°F (15.8°C) is noted during the month of September.

Humidity

The average relative humidity in September is 75%.

Rainfall

In Ellicott City, Maryland, during September, the rain falls for 13.1 days and regularly aggregates up to 2.17" (55mm) of precipitation. In Ellicott City, during the entire year, the rain falls for 165.5 days and collects up to 31.65" (804mm) of precipitation.

Snowfall

In Ellicott City, snow does not fall in May through October.

Daylight

In September, the average length of the day is 12h and 26min.
On the first day of the month, sunrise is at 6:36 am and sunset at 7:37 pm. On the last day of September, sunrise is at 7:02 am and sunset at 6:50 pm EDT.

Sunshine

The average sunshine in September is 9.1h.

UV index

In Ellicott City, the average daily maximum UV index in September is 5. A UV Index value of 3 to 5 symbolizes a moderate health risk from unprotected exposure to Sun's UV rays for the average person.
Note: The UV index of 5 during September translates into the following guidance:
Prioritize safety - The need to safeguard skin and eyes from harm is emphasized. Considering the Sun's intensity during midday, it's wise to minimize direct exposure. Fend off the sun's harsh rays with appropriate clothing, a wide-brim hat, and UV-protective sunglasses.
Updated: Jul 19, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What are the temperatures in September?

In September, the average high-temperature and low-temperature are 76.8°F (24.9°C) and 60.4°F (15.8°C) respectively. The average heat index (a.k.a. 'real feel', 'apparent temperature'), which combines relative humidity and air temperature, in August is estimated at 89.6°F (32°C).

What is the average humidity in September?

The average relative humidity in September is 75%.

How much does it rain in September?

In Ellicott City, in September, during 13.1 rainfall days, 2.17" (55mm) of precipitation is typically accumulated.

When it does not snow?

May through October are months without snowfall.

What is the average length of the day in September?

The average day length in September is 12h and 26min.

What time are sunrise and sunset in September?

In September, on the first day of the month, sunrise is at 6:36 am and sunset at 7:37 pm. On the last day of the month, sunrise is at 7:02 am and sunset at 6:50 pm EDT.

How long on average sun shines in September?

In September, the average sunshine duration is 9.1h.

What is the UV index intensity in September?

The average daily maximum UV index in September is 5. A UV Index estimate of 3 to 5 represents a moderate 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 September
Ellicott City, MD

Average temperature in September - Ellicott City, MD
  • Average high temperature in September: 76.8°F

The warmest month (with the highest average high temperature) is July (85.6°F).
The month with the lowest average high temperature is January (38.1°F).

  • Average low temperature in September: 60.4°F

The month with the highest average low temperature is July (68.7°F).
The coldest month (with the lowest average low temperature) is January (26.2°F).

Average pressure in September
Ellicott City, MD

Average pressure in September - Ellicott City, MD
  • Average pressure in September: 30.05"Hg

The month with the highest atmospheric pressure is November (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).

Average wind speed in September
Ellicott City, MD

Average wind speed in September - Ellicott City, MD
  • Average wind speed in September: 6.2mph

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

Average humidity in September
Ellicott City, MD

Average humidity in September - Ellicott City, MD
  • Average humidity in September: 75%

The months with the highest relative humidity are May and October (77%).
The month with the lowest relative humidity is July (71%).

Average rainfall in September
Ellicott City, MD

Average rainfall in September - Ellicott City, MD
  • Average rainfall in September: 2.17"

The wettest month (with the highest rainfall) is August (3.74").
The driest month (with the least rainfall) is January (2.05").

Average rainfall days in September
Ellicott City, MD

Average rainfall days in September - Ellicott City, MD
  • Average rainfall days in September: 13.1 days

The month with the highest number of rainy days is May (18.2 days).
The month with the least rainy days is January (9.7 days).

Average snowfall in September
Ellicott City, MD

Average snowfall in September - Ellicott City, MD
  • Average snowfall in September: 0"

The month with the highest snowfall is January (2.4").
The months with the least snowfall are May, June, July, August, September and October (0").

Average snowfall days in September
Ellicott City, MD

Average snowfall days in September - Ellicott City, MD
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is January (4.9 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).

Average daylight in September /
Average sunshine in September
Ellicott City, MD

Average daylight in September / Average sunshine in September - Ellicott City, MD
  • Average daylight in September: 12h 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 30min).

  • Average sunshine in September: 9h and 1min

The month with the most sunshine is July (Average sunshine: 10h and 48min).
The month with the least sunshine is February (Average sunshine: 5h and 0min).

Average sunshine days in September
Ellicott City, MD

Average sunshine days in September - Ellicott City, MD
  • Average sunshine days in September: 14.5 days

The month with the most sunshine days is November (18.5 days).
The month with the least sunshine days is May (10.4 days).

Average UV index in September
Ellicott City, MD

Average UV index in September - Ellicott City, MD
  • Average UV index in September: 5

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 September
Ellicott City, MD

Average cloud cover in September - Ellicott City, MD
  • Average cloud cover in September: 35

The month with the most cloud cover is March (Cloud cover 46).
The month with the least cloud cover is July (Cloud cover 29).

Average visibility in September
Ellicott City, MD

Average visibility in September - Ellicott City, MD
  • Average visibility in September: 6mi

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

Ellicott City, Maryland, USA

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