Marin County

Marin County Weather in September

Average temperatures, rainfall, sunshine and the best places to visit in Marin County, the United States of America in September.

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Novato San Rafael Mill Valley Sausalito

Considering a trip to Marin County, the United States of America this September and wondering about the expected weather conditions? Find all the crucial information you need right here, addressing your question:

What to Expect in Marin County in September

Marin County, the United States of America is a region in the United States of America. September in Marin County generally has temperatures that range from pleasant to warm, with almost no precipitation. During September, summer is in full swing.

Temperatures

During the day the temperature is pleasant in Sausalito at 21°C (70°F) and warm in Novato at 28°C (82°F). As night falls, temperatures generally drop to 11°C (52°F) in Novato and 13°C (55°F) in Sausalito. On average, September is the warmest month of the year in Marin County, the United States of America. So be prepared and pack summer clothes.

For specific regional insights in Marin County, the United States of America, refer to the map provided below.

Precipitation

September is a very dry month with an average rainfall of around 3.7 mm (0.1 in) in Novato.

Average sunshine

Most destinations offer generous amounts of sunshine this September. For example, Novato gets approximately 270 hours of sunlight, perfect for anyone wanting bright, sunny days.

Explore Marin County by month

Pick a month to see the average temperature, rainfall and sunshine in Marin County — and find the best time to visit. (based on Novato)

January14°C (57°F) February16°C (61°F) March18°C (64°F) April20°C (68°F) May22°C (72°F) June26°C (79°F) This monthJuly27°C (81°F) August27°C (81°F) September28°C (82°F) October24°C (75°F) November18°C (64°F) December14°C (57°F)
Best Time to Visit Marin County →

Best Places to Visit in Marin County in September

Click on a destination dot for more details. Toggle the map to compare temperatures or precipitation across Marin County.

Conditions Temperatures Precipitation
perfect weather
pleasant
tolerable
unpleasant
poor

Perfect weather is subjective. On this map perfect weather has been defined with temperatures between 20°C (68°F) and 29°C (84°F) and not too much precipitation (less than 90 mm (3.5 in) a month).

Popular Destinations in Marin County

What is the weather like in September for some of the most popular destinations in Marin County, the United States of America?

Temperature range in Marin County (September)

Precipitation variation in Marin County (September)

Novato

In September Novato generally has high temperatures with maximum daytime temperatures around 28°C (82°F), minimum nighttime temperatures around 11°C (52°F) and almost no monthly rainfall. So on average the conditions are perfect that month.

« August
September
October »
August
September
October
Max temperature
27°C (81°F)
28°C (82°F)
24°C (75°F)
Min temperature
11°C (52°F)
11°C (52°F)
9°C (48°F)
Monthly sun hours
288 hours
270 hours
243 hours
Monthly rainfall
0 mm (0 in)
3.7 mm (0.1 in)
31 mm (1.2 in)
Monthly rainy days
0 days
a single day
4 days
Weather conditions
perfect
perfect
perfect
Climate in Novato →

San Rafael

In September San Rafael generally has high temperatures with maximum daytime temperatures around 26°C (79°F), minimum nighttime temperatures around 12°C (54°F) and almost no monthly rainfall. So on average the conditions are perfect that month.

« August
September
October »
August
September
October
Max temperature
25°C (77°F)
26°C (79°F)
22°C (72°F)
Min temperature
12°C (54°F)
12°C (54°F)
11°C (52°F)
Monthly sun hours
288 hours
270 hours
243 hours
Monthly rainfall
0 mm (0 in)
4 mm (0.2 in)
44 mm (1.7 in)
Monthly rainy days
0 days
a single day
4 days
Weather conditions
perfect
perfect
perfect
Climate in San Rafael →

Mill Valley

In September Mill Valley generally has high temperatures with maximum daytime temperatures around 24°C (75°F), minimum nighttime temperatures around 12°C (54°F) and low monthly rainfall. So on average the conditions are perfect that month.

« August
September
October »
August
September
October
Max temperature
23°C (73°F)
24°C (75°F)
22°C (72°F)
Min temperature
12°C (54°F)
12°C (54°F)
11°C (52°F)
Monthly sun hours
288 hours
270 hours
243 hours
Monthly rainfall
0.3 mm (0.01 in)
5 mm (0.2 in)
50 mm (2 in)
Monthly rainy days
0 days
2 days
5 days
Weather conditions
perfect
perfect
perfect
Climate in Mill Valley →

Sausalito

In September Sausalito generally has pleasant temperatures with maximum daytime temperatures around 21°C (70°F), minimum nighttime temperatures around 13°C (55°F) and almost no monthly rainfall. So on average the conditions are perfect that month.

« August
September
October »
August
September
October
Max temperature
19°C (66°F)
21°C (70°F)
20°C (68°F)
Min temperature
13°C (55°F)
13°C (55°F)
12°C (54°F)
Monthly sun hours
288 hours
270 hours
243 hours
Monthly rainfall
0.4 mm (0.02 in)
3.8 mm (0.1 in)
34 mm (1.3 in)
Monthly rainy days
a single day
a single day
4 days
Weather conditions
perfect
perfect
perfect
Climate in Sausalito →

Fairfax

In September Fairfax generally has high temperatures with maximum daytime temperatures around 27°C (81°F), minimum nighttime temperatures around 12°C (54°F) and almost no monthly rainfall. So on average the conditions are perfect that month.

« August
September
October »
August
September
October
Max temperature
27°C (81°F)
27°C (81°F)
24°C (75°F)
Min temperature
12°C (54°F)
12°C (54°F)
11°C (52°F)
Monthly sun hours
288 hours
270 hours
243 hours
Monthly rainfall
0 mm (0 in)
4.3 mm (0.2 in)
55 mm (2.2 in)
Monthly rainy days
0 days
a single day
5 days
Weather conditions
perfect
perfect
perfect
Climate in Fairfax →

Is your destination not in the list? Have a look at all destinations in Marin County, in the United States of America.

Popular cities in September

Day & night temperatures, rainfall and average weather in Marin County in September.

City Weather Day temp Night temp Rainfall
Novato 28°C (82°F) 11°C (52°F) 3.7 mm (0.1 in)
San Rafael 26°C (79°F) 12°C (54°F) 4 mm (0.2 in)
Mill Valley 24°C (75°F) 12°C (54°F) 5 mm (0.2 in)
Sausalito 21°C (70°F) 13°C (55°F) 3.8 mm (0.1 in)
Fairfax 27°C (81°F) 12°C (54°F) 4.3 mm (0.2 in)
Larkspur 24°C (75°F) 12°C (54°F) 4.5 mm (0.2 in)

Marin County weather in September: frequently asked questions

What is the weather like in Marin County, the United States of America in September?

September in Marin County, the United States of America brings perfect weather. In Novato, daytime temperatures are typically around 28°C (82°F) and nighttime lows hover near 11°C (52°F).

What is the average temperature in Marin County, the United States of America in September?

Novato averages a daytime maximum of 28°C (82°F) in September, with overnight lows close to 11°C (52°F).

Does Marin County, the United States of America get a lot of rain in September?

Not particularly. Novato averages just 3.7 mm (0.1 in) of rain in September, making it a mostly dry month for Marin County, the United States of America.

Is September a Good Time to Visit Marin County, the United States of America?

We consider September to be one of the best times to travel to Marin County, the United States of America. Typically, the climate in Novato is perfect.

Generally speaking, the best visiting conditions can be found in April, May, June, July, August, September and October offering mostly perfect weather in Novato. In contrast, January, February and December tend to have unpleasant weather conditions.

Interested in more climate information?

We have much more information about the climate in Marin County.

Weather and climate has detailed information for every country in the world. Are you going to the United States of America? Get detailed historical weather averages for many cities in the United States of America.

Not sure yet where to go? We now have a tool which recommends destinations that suit your ideal travel conditions. Find out where to go with our weather planner.

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