flag Cornwall, Average Weather September

  • High Temperature
  • Low Temperature
  • Sea Temperature
  • Temperature
  • Rainfall

    70 mm
  • Rainfall Days

    19 days
  • Sunshine Hours

    5 hours

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September daily averages


September daily averages for Cornwall

  • 1st
    14 57
  • 2nd
    14 57
  • 3rd
    15 59
  • 4th
    14 57
  • 5th
    15 59
  • 6th
    14 57
  • 7th
    14 57
  • 8th
    14 57
  • 9th
    15 59
  • 10th
    15 59
  • 11th
    14 57
  • 12th
    15 59
  • 13th
    14 57
  • 14th
    14 57
  • 15th
    13 55
  • 16th
    14 57
  • 17th
    14 57
  • 18th
    14 57
  • 19th
    14 57
  • 20th
    14 57
  • 21st
    14 57
  • 22nd
    12 54
  • 23rd
    13 55
  • 24th
    14 57
  • 25th
    13 55
  • 26th
    13 55
  • 27th
    14 57
  • 28th
    14 57
  • 29th
    14 57
  • 30th
    14 57

What's The Summer Like In Cornwall In September

September marks the first month of autumn and also when temperatures on land and sea begin to start falling as winter is just around the corner. However, this is still one of the more popular times of the year to visit Cornwall as many of the crowds have gone home and water temperatures are still warm enough to enjoy. Additionally, there is always the chance of an Indian summer making the month warmer than normal and even more pleasant.


In addition to falling temperatures, this is also the beginning of the rainy season. After several months of relative dry weather, showers and thunderstorms are becoming more prevalent during this time of the year as more and stronger frontal systems begin to affect the region. As a result, rain amounts climb to an average of 70mm for the month. This rain will only fall over an average of 19 days, but some of it will be heavy and visitors need to dress appropriately.


While the region is experiencing wetter conditions, it is also getting slightly cooler. After experiencing the two warmest months of the year in July and August, this month is cooler with an average afternoon high of 17°C (63°F). Overnight lows are also slightly chillier with temperatures falling to an average low of 12°C (54°F). Combined with the clouds and rain, visitors will want to pack raingear, pants and plenty of long sleeves. Overall, the average daily temperature is 15°C (59°F).

Sunshine Hours

Additionally, the days are beginning to get shorter with only 8 hours of sunshine per day.

Sea Temperature

Even though it may be getting slightly cooler on land, the average water temperature is still pleasant enough for visitors to enjoy the beach for at least a few more weeks. The average water temperature for this time of the year is a mild 16°C (61°F). With fewer crowds, this is a great time to hit the beach and have plenty of room to spread out and enjoy all the water sports of the region.

Cornwall Hotels In September

Star Castle Hotel

With exceptional service as well as two award-winning restaurants, there is a lot to like about the Star Castle Hotel. Located on the Isles of Scilly and housed in a 16th century castle, the hotel is like none other in the region. The hotel features a total of 38 bedrooms, 4 acres of private gardens, a tennis court and an indoor pool. The hotel is also home to numerous dining and drinking options including a bar that is located in what was once the castle dungeon.

The Idle Rocks Hotel

The Idle Rocks Hotel is located in St. Mawes and contains a total of just 19 tastefully decorated rooms that contain a private bath, large beds, flat screen TVs and even under floor heating to help warm your feet on cold September mornings. Both child friendly and dog friendly, this hotel is the perfect choice to be within easy walking distance of many great attractions in Cornwall during the month of September.

Boskerris Hotel

Even though it is located on the Cornish coast, the Boskerris Hotel has a definite Mediterranean flare to it. Each of the 15 rooms has a stunning view of the ocean and with three different room styles to choose from; there is one to fit every guest's needs. All rooms contain free Wi-Fi, flat screen TVs, private baths and all the amenities of home. This is the perfect hotel for a long weekend holiday or just to get away from it all for a few days.

Cornwall Beachs For September

Harlyn Beach

One beach that is perfect for the whole family, including dogs, is Harlyn. Located on the northern coast of Cornwall, this beach offers good swimming and good surfing when the winds are out of the southwest. Lifeguards are also on duty throughout the summer months and the beach is wide enough for visitors to spread out and enjoy the 8 hours of sunshine the region experiences in September. The region is also easily accessible by car and there are basic toilets available nearby.

Bars And Restaurants

Restaurant Nathan Outlaw

Restaurant Nathan Outlaw is located in Port Isaac and takes advantage of its proximity to the sea to bring guests the best and finest in fresh fish. Reservations are encouraged at this highly popular eatery that changes its menu based on which fish are available. All dishes are cooked to order and contain small seafood plates.

Squid Ink

Located in Looe, Squid Ink offers some of the finest food and wine in the region. The menu changes based on the seasons so guests can rest assured that their food includes the freshest ingredients possible. Additionally, the majority of the produce used by the restaurants comes from within 30 miles of the city making it a true farm to table experience.

Fistral Beach Bar

Weekends are the time to be at the Fistral Beach Bar located in Newquay. On Fridays, Saturdays and Sundays guests are treated to a DJ or live music and can keep their groove going until the early morning hours. Additionally, both dogs and people are welcome to kick back and enjoy the bar's couches while watching sports on one of the many TVs. This is the perfect spot to sit and unwind while taking in a beautiful view of the ocean. 

Things To Do In Cornwall in September

AK Wildlife Cruises

The waters around Cornwall are teeming with animals and one of the best ways to see it is by booking a wildlife cruise. AK Wildlife Cruises offers visitors the chance to explore the southern coast and look for dolphins, sharks, seals and birds. Cruises range in length from four to seven hours so you can pick the right one for your family.

Cornish Riding Holidays

With just 70mm of rain expected in the month of September, now is a great time to explore the region on horseback. Cornish Riding Holidays offers children and adults an ultimate riding adventure and a number of different trips to choose from. Some visitors may even choose to spend their entire holiday with the company and stay on site or may decide a half-day or daylong trip is long enough.

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