McLean Weather in September

McLean in September sees high daytime temperatures of 26°C (79°F) and nighttime lows of 16°C (61°F). Rainfall is fairly high this month at around 119 mm (4.7 in), so pack a rain jacket to stay dry.

Rainfall in McLean in September

Looking at the last 30 years, the data shows about 9 days with rain, averaging 119 mm (4.7 in) for the month. The rain this month tends to fall in heavier spells rather than light drizzle. When it rains, showers can be significant.

Temperature in McLean in September

September in McLean sees highs of 26°C (79°F) and lows of 16°C (61°F) overnight. Overall, the month follows a fairly predictable daily temperature pattern. Nights drop to around 16°C (61°F), which is noticeably cooler than the daytime. A light jacket for the evening is a sensible addition, and the cool nights tend to make sleeping comfortable.

Sunshine in McLean in September

Expect a lot of sunshine this month, with about 225 hours of sun. These sunny conditions add to the overall experience.

Wind Speed in McLean in September

Wind speeds average 4 m/s (8 knots) during September. At this speed, expect moderate winds that can raise dust and move small branches. Since this is an average, some days have gentle light winds while others experience stronger breezes that are quite noticeable.

If you prefer dry days with pleasant temperatures, April typically offers the best circumstances. If you're seeking pleasant, dry and sunny weather somewhere else in the world, our weather planner can help you explore other options.

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For a detailed overview over the year and the best time to visit the United States of America, check out our McLean's climate page.

McLean Temperature in September

Min Temperature 16°C (61°F)  

Max Temperature 26°C (79°F)  

Chance of Rain 30%  

Precipitation 119 mm (4.7 in)  

Rainy days 9 days  

Humidity 68% *  

Windspeed 4 m/s (8 knots) *  

Sunshine 225 hours *  

Percentage Sunshine 60% *  

* Data from: Washington DC, the United States of America (15 KM, 9 Miles).

What to Wear in McLean in September

Warm temperatures in September make for comfortable sightseeing weather. Pack breathable fabrics like cotton shirts, knee-length shorts or skirts, and comfortable walking shoes. A thin long sleeve for indoor spaces is handy. Prepare for significant rainfall with proper waterproof clothing and shoes. You'll definitely want to pack sunglasses and sunscreen. There will be plenty of bright sunshine this month.

What To Do in McLean in September

We rated the following activities from 1 (least suitable) to 10 (best) to do.

Swimming

9/10

Cycling

7/10

Walking

7/10

Camping

6/10

Outdoor sports

7/10

Select a Month

Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit the United States of America, check out our McLean's climate page.

More climate data for McLean

Temperature Rainfall Sunshine Humidity Wind Speed

See the full McLean climate overview or explore weather in the United States of America.