May Weather in San Francisco, Panama

Last updated: August 27, 2025

Experience the vibrant May weather in San Francisco, Panama, where temperatures soar with a maximum of 35°C (96°F), averaging a comfortable 26°C (79°F) and dipping to a minimum of 21°C (70°F). This month brings a significant precipitation total of 355 mm (14.0 in) across 27 days, contributing to the region's lush greenery. With humidity levels at 73%, the atmosphere is rich and tropical, making it the perfect backdrop for outdoor adventures and cultural exploration. Embrace the warmth and occasional rain, and discover the unique charm of San Francisco in May!

May Temperature in San Francisco

In May, San Francisco and Panama experience pleasantly warm temperatures, making it a delightful time for outdoor activities. Both cities see a minimum temperature of around 21°C (70°F), which sets a comfortable baseline for the month. The average temperature in Panama remains slightly higher at 26°C (79°F), while San Francisco lingers at the same average but often feels cooler due to coastal breezes. Notably, Panama boasts a maximum temperature of 35°C (96°F), keeping the days toasty, contrasting with San Francisco's more moderate max of 33°C (91°F). As May progresses, the warmth continues to solidify, indicating a subtle trend toward increasing temperatures, especially in Panama, where the heat peaks in the earlier months of the year. Overall, this month serves as a transition into summer, offering a blend of mild and warmer days in both vibrant locales.

May Weather in San Francisco: Daily Temperature Highs, Lows, and Averages

The chart illustrates May temperature patterns in San Francisco, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In San Francisco, May typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec798081817978787877777778
Data source: Temperature data for San Francisco generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

May Precipitation in San Francisco

In San Francisco, Panama, May marks the peak of the rainy season, with a staggering 355 mm (14.0 in) of precipitation falling over the month, making it the wettest time of the year. This deluge is accompanied by a remarkable 27 days of rain, showcasing the region's transformation into a lush, vibrant landscape. Following the relatively dry periods of January (31 mm) and February (8 mm), the rainfall spikes significantly in April (105 mm) and continues its upward trend through the following months. As the year progresses into June and July, precipitation remains high, indicating a persistent rainy pattern, with each subsequent month barely trailing the rainfall of May. This trend underscores the region's tropical climate, where wet days dominate, particularly from April through September, highlighting its distinct wet season characteristics.

May Precipitation Trends in San Francisco

The chart displays monthly precipitation patterns in San Francisco, with values for each month alongside May’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how May’s conditions compare to those of other months. In San Francisco, May typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec3187105355353404359459411385103
Data source: Precipitation data for May generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

May Humidity in San Francisco

In May, San Francisco experiences a slight uptick in humidity, reaching 73%, which marks a subtle shift from the cooler, drier months of winter and spring. This trend aligns with a gradual rise in humidity from April's 70% as the city transitions into the warmer season. As the year progresses into June, the humidity skyrockets to a sweltering 90%, indicating a marked change in climate. Overall, the rising humidity in May hints at the beginning of San Francisco’s more humid summer months, setting the stage for the peaks that follow in the upcoming season.

May Average Humidity in San Francisco

This chart illustrates the average monthly humidity levels in San Francisco, with May’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In May, average humidity in San Francisco is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec72%71%69%70%73%90%89%87%87%86%86%79%
Data source: Humidity data for May generated using information from the Copernicus Climate Change Service.

May UV Index in San Francisco

In May, San Francisco, Panama, experiences an extreme UV Index of 15, maintaining the high levels noted from previous months. This consistent intensity means that residents and visitors should exercise caution, as the effective burn time remains a swift 10 minutes. The trend from January through May showcases a progressive increase in UV exposure, peaking in April and May before slightly lowering in the following months. As the sun shines brightly, it's crucial to protect your skin and stay informed about the UV Index. For detailed information on UV levels and safety tips, visit San Francisco UV Index.

Maximum UV Index Levels in San Francisco for May

The chart shows the monthly maximum UV Index (UVI) for San Francisco in May, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In May, the maximum UV index in San Francisco typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec121314151513141314141211
Data source: San Francisco May UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

May Sunshine in San Francisco

As spring blossoms into summer, May in San Francisco ushers in a mix of sunshine and fog, presenting a charming contrast to the golden rays of earlier months. With 229 hours of sunlight, May sees a dip from the peak brightness of March at 335 hours, yet it still offers ample opportunities for outdoor adventures. This trend of fluctuating sunshine continues into the summer months, with June and July presenting the lowest hours at around 213 and 210 respectively. Notably, the year wraps up with a bright December boasting 301 hours, promising a vibrant close to 2023. The Santa Ana winds may challenge the fog's dominance, but the city consistently shines through the array of seasonal changes.

Monthly Sunshine Duration in San Francisco: May Highlighted

The May sunshine duration represents the total number of hours San Francisco experiences direct sunlight during the month of May, excluding cloudy or obstructed periods. This chart compares the sunshine duration of May with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec254h299h335h300h229h213h210h207h217h224h240h301h
Data source: San Francisco May Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in San Francisco During May

In San Francisco, Panama, the trend in sunshine likelihood reveals a striking dip in May, with only a 9% chance of experiencing sunny weather. This dramatic drop follows a relatively promising April at 17% and is part of a broader pattern where the months leading into May, such as March at 47% and February at 41%, show a much higher probability of sun. As the rainy season approaches, the chances remain low through the summer months, with June and July only offering 10% and 13% chances, respectively. This shift underscores the importance of planning for more overcast conditions during May if you're hoping to soak up the sun in this vibrant coastal city.

Percentage of Sunny Days in May in San Francisco

The chart illustrates the percentage of sunny days in San Francisco throughout the year, with May highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often San Francisco experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec45%41%47%17%9%10%14%5%11%16%22%43%
Data source: San Francisco May chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in San Francisco in May

In San Francisco, the daylight duration shows a rhythmic pattern throughout the year, with consistent 11-hour days in January and February that gradually give way to longer 12-hour stretches from March through August. As spring blooms into summer, residents enjoy maximum brightness, creating the perfect backdrop for outdoor activities. Interestingly, as the summer wanes, daylight doesn’t immediately retreat; it remains at 12 hours until September before transitioning back to 11 hours as the year draws to a close. This gentle ebb and flow of sunlight not only highlights the city’s diverse seasons but also invites residents and visitors alike to savor each moment under the sun.

Average Daylight Hours in San Francisco for May

The chart illustrates the variation in daylight duration in San Francisco throughout the year, with May highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec11h 41m11h 51m12h 4m12h 17m12h 29m12h 34m12h 31m12h 21m12h 8m11h 55m11h 44m11h 38m
Data source: San Francisco daylight hours, calculated by summing the hours between sunrise and sunset for each day.

May Winds in San Francisco

In San Francisco, the May winds unveil a gentle whisper, with average speeds dropping to a mild 1.3 m/s (3 mph). This marks a notable decline from the breezier months of early spring, particularly March's 3.3 m/s (7 mph). As we transition into summer, the wind remains consistently calm, hovering around similar speeds through June, July, and August. It seems that while the city is known for its characteristic fog and breezes, May offers a tranquil breath before the warmer months take center stage, creating a peaceful backdrop for residents and visitors alike to enjoy the beauty of this iconic coastal city.

Average May Wind Speed in San Francisco

The chart displays monthly wind speed patterns in San Francisco, with values for each month shown alongside May's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how May's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec2.52.93.31.91.3 m/s1.31.31.41.21.41.31.7
Data source: San Francisco May wind data, generated using information from the Copernicus Climate Change Service.

How May Weather in San Francisco Compares to Other Months

Weather in San Francisco varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in San Francisco, focusing on differences in temperature, rainfall, humidity, and UV levels.

May typically exhibits hotter weather compared to January, with temperatures ranging from a minimum of 21°C (70°F) to a maximum of 35°C (96°F) and an average of 26°C (79°F). In contrast, January is slightly cooler, with temperatures ranging from a minimum of 20°C (68°F) to a maximum of 33°C (91°F), also averaging 26°C (79°F). Another notable difference is the precipitation; May experiences significantly more rainfall, with 355 mm (14.0 in) over 27 days, while January sees only 31 mm (1.2 in) over just 4 days. Humidity levels are quite similar in both months, with May at 73% and January at 72%. For more detailed information, check out San Francisco weather in January.

May and February both feature warm temperatures, but they differ significantly in rainfall and humidity. In May, temperatures range from a minimum of 21°C (70°F) to a maximum of 35°C (96°F), with an average of 26°C (79°F), accompanied by substantial precipitation of 355 mm (14.0 in) over 27 days, which contributes to a higher humidity level of 73%. In contrast, February sees slightly cooler temperatures, with a minimum of 20°C (68°F) and a maximum of 34°C (94°F), averaging 27°C (80°F). This month typically experiences very little rainfall, registering only 8 mm (0.3 in) across no rainy days, resulting in a lower humidity of 71%. For more details on February weather, you can visit San Francisco weather in February.

In comparing the weather between March and May, we see notable differences in temperature and precipitation. March enjoys slightly warmer average temperatures, with a minimum of 21°C (70°F) and an average of 27°C (81°F), while May has a greater range, with a minimum of 21°C (70°F) and a maximum reaching 35°C (96°F). However, May is significantly wetter, experiencing 355 mm (14.0 in) of precipitation over 27 days, in stark contrast to March's minimal 7 mm (0.3 in) of rain over zero days. Additionally, humidity levels are fairly comparable, with March at 69% and May slightly higher at 73%. For more detailed insights on weather conditions during this month, you can refer to the following link: San Francisco weather in March.

In comparing the weather of May and April, both months feature similar minimum temperatures, typically starting at around 21°C (70°F). However, April sees a slightly warmer average temperature of 27°C (81°F) compared to May’s average of 26°C (79°F). Interestingly, while May experiences a substantial increase in rainfall, totaling 355 mm (14.0 in) over 27 days, April's precipitation is significantly lower at 105 mm (4.1 in) across just 12 days. Additionally, humidity levels are slightly higher in May at 73%, as opposed to April's 70%. For those interested in more specifics, you can check the San Francisco weather in April.

In comparing the weather between May and June, both months exhibit similar temperature ranges, with minimums around 21°C (70°F) and average temperatures hovering between 26°C (78°F in June and 79°F in May). However, June slightly cooler with a maximum of 33°C (92°F), compared to May's peak at 35°C (96°F). Precipitation remains high in both months, with May experiencing 355 mm (14.0 in) over 27 days and June seeing a near-identical 353 mm (13.9 in) over 28 days. Notably, humidity increases from 73% in May to a more oppressive 90% in June, contributing to a muggier feel. For more detailed insights, check out the San Francisco weather in June.

In May, temperatures typically range from a minimum of 21°C (70°F) to a maximum of 35°C (96°F), with an average temperature of 26°C (79°F). However, this month also sees significant rainfall, with approximately 355 mm (14.0 in) of precipitation over 27 days and a humidity level of 73%. In contrast, July maintains a similar average temperature of 26°C (78°F) but has slightly lower maximums, peaking at 33°C (92°F). July is characterized by increased rainfall, accumulating about 404 mm (15.9 in) across 28 days, and higher humidity at 88%. For more detailed insights, you can check San Francisco weather in July.

In comparing the weather between May and August, both months exhibit warm temperatures, but with notable differences. May boasts a higher average temperature of 26°C (79°F) and can reach a maximum of 35°C (96°F), while August has a slightly lower average of 25°C (78°F) and peaks at 33°C (91°F). Precipitation levels are quite similar, with May receiving 355 mm (14.0 in) over 27 days and August slightly higher at 359 mm (14.1 in) across 29 days. Additionally, humidity rises from 73% in May to 87% in August, contributing to a more humid and rainy atmosphere later in the summer. For a detailed look at August conditions, you can consult San Francisco weather in August.

In May, the weather typically boasts warmer temperatures with an average high of 26°C (79°F) and a maximum reaching up to 35°C (96°F). This month experiences considerable rainfall, with a total precipitation of 355 mm (14.0 in) spread over 27 days and a humidity level of 73%. In contrast, September sees slightly cooler temperatures, averaging 25°C (78°F) and peaking at 32°C (91°F). However, this month has higher precipitation levels at 459 mm (18.1 in) over 30 days and increased humidity at 87%. For more details on September's weather in comparison, you can visit San Francisco weather in September.

May and October present differing weather characteristics, despite having similar minimum temperatures. In May, average temperatures hover around 26°C (79°F), with highs reaching up to 35°C (96°F), while October experiences slightly lower average temperatures of 25°C (77°F) and maximums of 32°C (90°F). Precipitation is notably higher in October, with 410 mm (16.2 in) spread over 29 days compared to May's 355 mm (14.0 in) over 27 days. Additionally, October has a higher humidity level at 86%, compared to May's 73%. For more detailed insights, check out San Francisco weather in October.

In May, temperatures range from a minimum of 21°C (70°F) to a maximum of 35°C (96°F), with an average temperature of 26°C (79°F). The month experiences significant rainfall, totaling 355 mm (14.0 in) over 27 days, along with a humidity level of 73%. In contrast, November features slightly cooler temperatures, with a maximum of 32°C (90°F) and an average of 25°C (77°F), while the minimum remains the same at 21°C (70°F). Rainfall in November is slightly higher at 385 mm (15.1 in) over 26 days, and humidity increases to 86%. For more detailed information on weather variations, check out San Francisco weather in November.

In May, temperatures soar with a minimum of 21°C (70°F) and an average of 26°C (79°F), reaching highs of 35°C (96°F), while December remains slightly cooler with a minimum of 20°C (69°F) and a maximum of 32°C (90°F). The wet season in May results in significant rainfall, with 355 mm (14.0 in) over 27 days, compared to a much drier December, which sees only 103 mm (4.1 in) across 9 days. Although both months have similar average temperatures, December's higher humidity at 79% contrasts with May's 73%, making it feel quite different. For more detailed insights into weather conditions, you can check San Francisco weather in December.

Compare San Francisco's Climate with Cities Worldwide

Conclusion: What to Expect From May Weather in San Francisco

As May rolls into San Francisco, it brings a notable shift in weather compared to the earlier months of the year. The city experiences a delightful increase in temperatures, with the average soaring to a pleasant warmth, inviting locals and tourists alike to enjoy outdoor activities. However, the flip side is a significant rise in precipitation, as May witnesses an increase in rainy days, casting a slightly moody but enchanting atmosphere across the region. This month tends to be more humid, adding a tropical twist to the California backdrop. Whether you’re strolling along the iconic waterfront or exploring the vibrant neighborhoods, May's unique climate offers a captivating experience distinct from the drier, cooler months that precede it. For more details on how weather varies throughout the year, check out San Francisco Climate.