Climate - Guaymas (Sonora)

The climate of Guaymas is sub-tropical desert, with a pleasantly warm winter from December to February, and a hot summer from April to October, within which there is a muggy and relatively rainy period from July to October.
The city is located in the state of Sonora, on the coast of the Gulf of California (or Cortés Sea), at the 27th parallel, south of Hermosillo. On colder winter nights, the temperature can drop to 6/7 °C (43/45 °F), but in some years to as low as 2/3 °C (35/36 °F), while during the day it remains mild.
Typically, the highest temperatures, even more than 40 °C (104 °F), occur in June, but then, in July and August, the humidity increases and the heat becomes oppressive. The minimum temperatures often remain around 30 °C (86 °F).
From June to November, but with a higher probability from August to October, Guaymas can be affected by hurricanes of the Pacific Ocean, which generally arrive weakened, but sometimes they can bring heavy rains, as happened with Hurricane Jimena in September 2009. In any case, hurricanes are rare in June, the month in which they are most frequent is September, and in the past they have never occurred in November.
The average temperature of the coldest month (January) is of 17.9 °C (64.2 °F), that of the warmest months (July and August) is of 32.4 °C (90.3 °F). Here are the average temperatures.

Precipitation amounts to 220 millimeters (8.7 inches) per year: it is therefore scarce. It ranges from 0 mm (0 in) in the driest months (April, May, June) to 70 mm (2.8 in) in the wettest (August). The rains from July to September are due to the humid air that rises from the Gulf of California, and sometimes by the remnants of tropical cyclones that can reach the area. Here is the average precipitation.

On average, there are around 2,900 sunshine hours per year. Here are the average sunshine hours per day.

The sea temperature ranges between 18 °C (64 °F) and 30.5 °C (87 °F). The sea is quite cold from December to April, while it becomes very warm from June to October. Here are the average sea temperatures.

Best Time

Guaymas can be visited from mid-November to March, as it is the mildest season. During the day you can enjoy the sun, while in the evening you will need a sweater and a jacket.
For a beach holiday, you can go from mid-April to mid-May and in the first half of November.

Guaymas - Weather by month

Based on the period 1991-2020

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In January, the weather in Guaymas is usually very mild. The average temperature is of 17.9 °C (64 °F), with a minimum of 11.6 °C (52.8 °F) and a maximum of 24.2 °C (75.6 °F).
On the coldest nights of the month, the temperature usually drops to around 5.5 °C (42.5 °F). However, it dropped to 2 °C (35.6 °F) in January 1997.
On the warmest days of the month, the temperature usually reaches around 29 °C (84 °F). However, it reached 35.4 °C (95.7 °F) in January 2018.
Precipitation amounts to 15 mm (0.6 in), distributed over 2 days.
The day lasts on average 10 hours and 35 minutes.
There are on average 6.5 hours of sunshine per day. So, the sun shines 63% of the time.
The average humidity is 50%.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 18.5 °C (65 °F). Therefore, the sea is very cool for swimming.

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In February, the weather in Guaymas is usually warm. The average temperature is of 19.1 °C (66 °F), with a minimum of 13 °C (55.4 °F) and a maximum of 25.1 °C (77.2 °F).
On the coldest nights of the month, the temperature usually drops to around 7 °C (45 °F). However, it dropped to 2 °C (35.6 °F) in February 1997.
On the warmest days of the month, the temperature usually reaches around 31 °C (87.5 °F). However, it reached 34.2 °C (93.6 °F) in February 2018.
Precipitation amounts to only 5 mm (0.2 in), and all occurs in one day.
The day lasts on average 11 hours and 10 minutes.
There are on average 7.5 hours of sunshine per day. So, the sun shines 69% of the time.
The average humidity is 48%.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 18.5 °C (65 °F). Therefore, the sea is very cool for swimming.

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In March, the weather in Guaymas is usually warm. The average temperature is of 21.1 °C (70 °F), with a minimum of 14.8 °C (58.6 °F) and a maximum of 27.4 °C (81.2 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 9 °C (48.5 °F). However, it dropped to 5 °C (41 °F) in March 2001.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 33 °C (91.5 °F). However, it reached 37.5 °C (99.5 °F) in March 2018.
Precipitation amounts to only 5 mm (0.2 in), and all occurs in one day.
The day lasts on average 12 hours and 0 minutes.
There are on average 7.5 hours of sunshine per day. So, the sun shines 62% of the time.
The average humidity is 44%.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 19.5 °C (66.5 °F). Therefore, the sea is very cool for swimming.

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In April, the weather in Guaymas is usually warm to hot. The average temperature is of 23.7 °C (75 °F), with a minimum of 17.8 °C (64.1 °F) and a maximum of 29.5 °C (85.1 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 12.5 °C (54.5 °F). However, it dropped to 9 °C (48.2 °F) in April 1996.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 35 °C (95.5 °F). However, it reached 39 °C (102.2 °F) in April 2006.
Precipitation amounts to only 0 mm (0 in), so on average it never rains in the whole month.
The day lasts on average 12 hours and 55 minutes.
There are on average 8.5 hours of sunshine per day. So, the sun shines 65% of the time.
The average humidity is 42%.
The average wind speed is 12 kph (8 mph).
The average sea temperature is of 21.5 °C (70.5 °F). Therefore, the sea is cool for swimming.

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In May, the weather in Guaymas is usually warm to hot. The average temperature is of 27.0 °C (81 °F), with a minimum of 21.8 °C (71.2 °F) and a maximum of 32.3 °C (90.1 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 16.5 °C (61.5 °F). However, it dropped to 14 °C (57.2 °F) in May 1991.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 37 °C (99 °F). However, it reached 44.1 °C (111.4 °F) in May 2018.
Precipitation amounts to only 0 mm (0 in), so on average it never rains in the whole month.
The day lasts on average 13 hours and 35 minutes.
There are on average 9.5 hours of sunshine per day. So, the sun shines 69% of the time.
The average humidity is 41%.
The average wind speed is 13 kph (8 mph).
The average sea temperature is of 24 °C (75.5 °F). Therefore, the sea is warm enough for swimming.

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In June, the weather in Guaymas is usually very hot. The average temperature is of 30.9 °C (88 °F), with a minimum of 26.7 °C (80 °F) and a maximum of 35.2 °C (95.3 °F).
On the coldest nights, the temperature usually drops to around 21.5 °C (70.5 °F). However, it dropped to 18 °C (64.4 °F) in June 1997.
On the warmest days, the temperature usually reaches around 40 °C (104 °F). However, it reached 44 °C (111.2 °F) in June 1998.
Precipitation amounts to only 0 mm (0 in), so on average it never rains in the whole month.
The day lasts on average 13 hours and 55 minutes. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.
There are on average 10 hours of sunshine per day. So, the sun shines 72% of the time.
The average humidity is 49%.
The average wind speed is 13 kph (8 mph).
The average sea temperature is of 27.5 °C (82 °F). Therefore, the sea is pleasantly warm and allows long swims.

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In July, the warmest month of the year, the weather in Guaymas is usually scorchingly hot. The average temperature is of 32.4 °C (90 °F), with a minimum of 29.1 °C (84.3 °F) and a maximum of 35.8 °C (96.4 °F).
On the coldest nights of the month, the temperature usually drops to around 25 °C (77.5 °F). However, it dropped to 22 °C (71.6 °F) in July 2003.
On the warmest days of the month, the temperature usually reaches around 39.5 °C (103 °F). However, it reached 43 °C (109.4 °F) in July 1997.
Precipitation amounts to 45 mm (1.8 in), distributed over 6 days.
The day lasts on average 13 hours and 40 minutes.
There are on average 8 hours of sunshine per day. So, the sun shines 58% of the time.
The average humidity is 58%.
The average wind speed is 13 kph (8 mph).
The average sea temperature is of 29.5 °C (85.5 °F). Therefore, the sea is pleasantly warm and allows long swims.

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In August, the weather in Guaymas is usually scorchingly hot. The average temperature is of 32.4 °C (90 °F), with a minimum of 28.9 °C (84 °F) and a maximum of 35.9 °C (96.6 °F).
On the coldest nights of the month, the temperature usually drops to around 24.5 °C (76 °F). However, it dropped to 22 °C (71.6 °F) in August 1991.
On the warmest days of the month, the temperature usually reaches around 39.5 °C (103 °F). However, it reached 42 °C (107.6 °F) in August 2005.
Precipitation amounts to 70 mm (2.8 in), distributed over 7 days.
The day lasts on average 13 hours and 5 minutes.
There are on average 8 hours of sunshine per day. So, the sun shines 59% of the time.
The average humidity is 63%.
The average wind speed is 13 kph (8 mph).
The average sea temperature is of 30.5 °C (87 °F). Therefore, the sea is pleasantly warm and allows long swims.

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In September, the weather in Guaymas is usually very hot. The average temperature is of 31.1 °C (88 °F), with a minimum of 27.2 °C (80.9 °F) and a maximum of 35.1 °C (95.2 °F).
On the coldest nights, the temperature usually drops to around 22 °C (72 °F). However, it dropped to 19 °C (66.2 °F) in September 1993.
On the warmest days, the temperature usually reaches around 39 °C (102 °F). However, it reached 45.1 °C (113.2 °F) in September 2020.
Precipitation amounts to 35 mm (1.4 in), distributed over 3 days.
The day lasts on average 12 hours and 20 minutes.
There are on average 8 hours of sunshine per day. So, the sun shines 64% of the time.
The average humidity is 63%.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 30 °C (86.5 °F). Therefore, the sea is pleasantly warm and allows long swims.

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In October, the weather in Guaymas is usually warm to hot. The average temperature is of 27.2 °C (81 °F), with a minimum of 21.7 °C (71 °F) and a maximum of 32.7 °C (90.9 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 15.5 °C (60 °F). However, it dropped to 9.3 °C (48.7 °F) in October 2020.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 37.5 °C (99.5 °F). However, it reached 40.5 °C (104.9 °F) in October 2020.
Precipitation amounts to 15 mm (0.6 in), distributed over 2 days.
The day lasts on average 11 hours and 30 minutes.
There are on average 8 hours of sunshine per day. So, the sun shines 71% of the time.
The average humidity is 53%.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 28 °C (82.5 °F). Therefore, the sea is pleasantly warm and allows long swims.

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In November, the weather in Guaymas is usually warm. The average temperature is of 22.2 °C (72 °F), with a minimum of 16.3 °C (61.4 °F) and a maximum of 28.1 °C (82.6 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 9.5 °C (49 °F). However, it dropped to 4 °C (39.2 °F) in November 2003.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 33.5 °C (92.5 °F). However, it reached 39 °C (102.2 °F) in November 2020.
Precipitation amounts to 10 mm (0.4 in), and all occurs in one day.
The day lasts on average 10 hours and 40 minutes.
There are on average 7.5 hours of sunshine per day. So, the sun shines 69% of the time.
The average humidity is 51%.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 24 °C (75.5 °F). Therefore, the sea is warm enough for swimming.

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In December, the coldest month of the year, the weather in Guaymas is usually very mild. The average temperature is of 17.8 °C (64 °F), with a minimum of 11.7 °C (53 °F) and a maximum of 23.9 °C (75.1 °F).
On the coldest nights of the month, the temperature usually drops to around 5.5 °C (42 °F). However, it dropped to 1 °C (33.8 °F) in December 2003.
On the warmest days of the month, the temperature usually reaches around 29 °C (84.5 °F). However, it reached 32 °C (89.6 °F) in December 2004.
Precipitation amounts to 15 mm (0.6 in), distributed over 2 days.
The day lasts on average 10 hours and 25 minutes. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.
There are on average 6.5 hours of sunshine per day. So, the sun shines 62% of the time.
The average humidity is 51%.
The average wind speed is 9 kph (5 mph).
The average sea temperature is of 20 °C (68 °F). Therefore, the sea is very cool for swimming.