May Weather in Tucson, United States

Last updated: February 24, 2025

May in Tucson, United States, presents a vibrant transition into summer with maximum temperatures soaring up to 40°C (104°F) and a comfortable average of 25°C (78°F). The month witnesses a rare minimum temperature dipping to 9°C (48°F), creating a diverse climate experience. Rain is scarce, with only 3 mm (0.1 in) of precipitation recorded over just one day, resulting in lower humidity levels at 40%. With mostly dry days and plenty of sunshine, May offers an inviting atmosphere for outdoor activities, making it a delightful time to explore the beauty of Tucson.

May Temperature in Tucson

In Tucson, United States, May marks a significant transition towards the heat of summer, with temperatures showcasing a notable upward trend. The month's minimum temperature sits at a comfortable 9°C (48°F), while the average climbs to 25°C (78°F), reflecting the region's warming climate. With a striking maximum of 40°C (104°F), May serves as a precursor to the scorching summer months ahead. This progression from the cooler spring temperatures is evident when comparing May to earlier months, such as April, where temperatures average around 22°C (71°F). As Tucson gears up for summer, May is a vibrant month that invites residents and visitors alike to enjoy the sunny weather while preparing for the intense heat of June and beyond.

May Weather in Tucson: Daily Temperature Highs, Lows, and Averages

The chart illustrates May temperature patterns in Tucson, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec525562717788888783736354
Data source: Temperature data for Tucson generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

May Precipitation in Tucson

In Tucson, May typically marks a transition to the drier months, with precipitation averaging just 3 mm (0.1 in), making it one of the driest months of the year, alongside April. This month experiences rainfall on only 1 day, highlighting a significant dip from the wetter winter months. As the desert climate prevails, the minimal moisture sets the stage for the hotter summer ahead, following a pattern where rainfall significantly increases in July. With such low precipitation, May stands out as a time when the landscape begins to reflect the arid beauty characteristic of Tucson, showcasing vibrant desert flora against the backdrop of rising temperatures.

May Precipitation Trends in Tucson

The chart displays monthly precipitation patterns in Tucson, 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.
JanFebMarAprMayJunJulAugSepOctNovDec233416238543527101427
Data source: Precipitation data for May generated using information from the Copernicus Climate Change Service.
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May Humidity in Tucson

In Tucson, United States, May marks a significant drop in humidity levels, registering at a comfortable 40%. This reduction continues the trend observed through the spring months, where humidity steadily decreases from 79% in February to April's 55%. By the time May arrives, residents and visitors alike can enjoy the warm, dry air that characterizes the desert climate, making it an ideal month for outdoor activities. As the summer approaches, humidity levels will lower even further, reaching a notably low 33% by June. This transition sets the stage for Tucson's signature dry heat, offering a refreshing reprieve from the higher humidity typical of winter months.

May Average Humidity in Tucson

This chart illustrates the average monthly humidity levels in Tucson, with May's data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, allowing you to see how May's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec76%79%67%55%40%33%34%48%64%67%77%82%
Data source: Humidity data for May generated using information from the Copernicus Climate Change Service.

May UV Index in Tucson

As May arrives in Tucson, the UV Index escalates to 12, placing it firmly in the extreme exposure category and signaling a crucial time for sun safety awareness. This month sees a continuation of high UV levels that began in April, where the index also reached 11. With a burn time of just 10 minutes, it's essential for residents and visitors alike to take precautions when enjoying outdoor activities. The trend observed from January to May demonstrates a significant rise in UV intensity, moving from a moderate level in January to extreme levels by spring. As summer approaches, similar high readings persist, with June and July maintaining a UV Index of 12. For more specific insights on UV levels throughout the year, explore Tucson UV Index.

Maximum UV Index Levels in Tucson for May

The chart shows the monthly maximum UV Index (UVI) for Tucson 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.
JanFebMarAprMayJunJulAugSepOctNovDec579111212121111864
Data source: Tucson 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 Tucson

As the year unfolds in Tucson, May shines brightly, boasting an impressive 371 hours of sunshine—a peak that the city maintains through June. This vibrant month reveals a trend of steadily increasing sunlight, beginning with 204 hours in January and steadily climbing to 333 hours by April. The escalating hours of sunlight encourage outdoor activities and foster a lively atmosphere, welcoming residents and visitors alike to bask in the warm, inviting climate. After May, the sun begins to retreat slightly, but even 354 hours in July keeps the spirit of summer alive, illustrating Tucson’s radiant appeal throughout these warmer months.

Monthly Sunshine Duration in Tucson: May Highlighted

The May sunshine duration represents the total number of hours Tucson 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.
JanFebMarAprMayJunJulAugSepOctNovDec204h241h304h333h371h371h354h340h312h300h261h243h
Data source: Tucson May Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Tucson During May

As spring transitions into summer, Tucson’s weather reveals a promising trend towards sunny days, particularly in May, where the chance of sunshine reaches an impressive 88%. This marks a notable increase from the preceding months, maintaining the 76% sun probability seen in April. As temperatures begin to rise, residents can look forward to more vibrant days, making May an ideal time for outdoor activities. Interestingly, this sunny peak is followed by a dip in July, where the likelihood of sunshine plummets to just 34%, highlighting the unique climatic patterns of the region. Overall, May stands out as a beacon of brightness in Tucson's annual weather cycle.

Percentage of Sunny Days in May in Tucson

The chart illustrates the percentage of sunny days in Tucson 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 Tucson experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec67%76%76%76%88%73%34%56%66%81%70%59%
Data source: Tucson May chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Tucson in May

As spring unfolds in Tucson, May brings a delightful increase in daylight, with the sun illuminating the city for 13 hours each day. This uptick continues the upward trend established since February, moving from 11 hours to a glorious 12 hours in March, and then 12 hours in April. With the arrival of May, daylight hours reach their peak for the month, creating the perfect backdrop for outdoor activities, blooming landscapes, and vibrant community events. As summer approaches, June will see even more daylight, topping out at 14 hours. This gradual escalation not only highlights Tucson’s warmer climate but also invites residents and visitors alike to soak in the additional sunshine before it begins to wane again later in the year.

Average Daylight Hours in Tucson for May

The chart illustrates the variation in daylight duration in Tucson throughout the year, with May highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 17m11h 2m12h12h 59m13h 48m14h 12m13h 59m13h 15m12h 18m11h 20m10h 29m10h 3m
Data source: Tucson daylight hours, calculated by summing the hours between sunrise and sunset for each day.

May Winds in Tucson

In Tucson, May marks the continuation of the spring breeze, maintaining a gentle wind speed of 3.3 m/s (7 mph), a figure consistent with both March and April. This stability hints at a pleasant transition into summer, as the winds remain notably stronger early in the year before tapering off in the hotter months. Notably, the upcoming June sees a slight dip to 3.0 m/s (7 mph), and even more in July and August, where the winds soften to 2.2 m/s (5 mph) and 2.1 m/s (5 mph), respectively. As the year progresses, the trend of decreasing winds continues into the fall, suggesting that Tucson's May offers a brief, refreshing gust before the summer heat settles in.

Average May Wind Speed in Tucson

The chart displays monthly wind speed patterns in Tucson, 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.
JanFebMarAprMayJunJulAugSepOctNovDec2.82.83.33.33.3 m/s3.02.22.12.12.62.52.3
Data source: Tucson May wind data, generated using information from the Copernicus Climate Change Service.

How May Weather in Tucson Compares to Other Months

The weather in Tucson changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of May's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Tucson and find detailed weather information for every month.

May and January offer starkly contrasting weather conditions. In May, temperatures range from a mild 9°C (48°F) at night to a sizzling 40°C (104°F) during the day, with low humidity averaging around 40% and minimal precipitation of just 3 mm over one day. In contrast, January brings cooler temperatures, with nighttime lows dropping to -1°C (30°F) and daytime highs reaching only 25°C (77°F). Additionally, January experiences higher humidity at 76% and a more significant rainfall total of 23 mm across three days. For a detailed look at January conditions, you can visit Tucson weather in January.

May and February offer starkly contrasting weather conditions. In May, temperatures can rise from a low of 9°C (48°F) to a scorching high of 40°C (104°F), with an average temperature of 25°C (78°F). The month is relatively dry, featuring only 3 mm (0.1 in) of precipitation and a humidity level of 40%. In contrast, February is much cooler, with temperatures ranging from a minimum of -3°C (27°F) to a maximum of 29°C (84°F), averaging around 13°C (55°F). This month also experiences significantly more precipitation at 34 mm (1.3 in) over about 4 days and a higher humidity of 79%. For more details on February weather, you can check Tucson weather in February.

When comparing the weather in March and May, the differences are quite striking. March experiences cooler temperatures, with a minimum of 1°C (33°F) and an average of 16°C (62°F), while May hits much warmer averages, peaking at 25°C (78°F) during the day and soaring up to a maximum of 40°C (104°F). March is characterized by higher humidity at 67% and more precipitation, with 15 mm (0.6 in) falling over three days, compared to the drier conditions in May, which sees only 3 mm (0.1 in) over just one day and a lower humidity level of 40%. For more detailed insights, you can check Tucson weather in March.

In comparing the weather of April and May, May exhibits a broader temperature range with a minimum of 9°C (48°F) and a maximum of 40°C (104°F), compared to April's minimum of 6°C (43°F) and maximum of 37°C (98°F). The average temperature in May rises to 25°C (78°F), making it noticeably warmer than April's average of 22°C (71°F). Both months experience minimal precipitation, with May receiving just 3 mm (0.1 in) of rain over one day, while April records only 2 mm (0.1 in) across no rainy days. Interestingly, May also has lower humidity at 40%, compared to April's higher humidity level of 55%. For more detailed insights on April's weather, you can check out Tucson weather in April.

May and June present a noticeable shift in weather patterns. In May, temperatures range from a minimum of 9°C (48°F) to a maximum of 40°C (104°F), with an average of 25°C (78°F) and very low precipitation of just 3 mm (0.1 in) over a single day. Humidity sits at 40%, creating a moderately dry environment. In contrast, June brings higher temperatures, with a minimum of 17°C (62°F) and a peak of 44°C (111°F), averaging at 31°C (88°F). Despite slightly increased precipitation to 8 mm (0.3 in), June boasts completely dry days and lower humidity at 33%. For more detailed information, you can check out Tucson weather in June.

May and July exhibit distinctly different weather patterns in Tucson. In May, temperatures range from a cool minimum of 9°C (48°F) to an average of 25°C (78°F), with a maximum peaking at 40°C (104°F). The month is relatively dry, receiving only 3 mm (0.1 in) of precipitation over just one day, and humidity levels sit at 40%. Conversely, July experiences warmer temperatures, with a minimum of 20°C (69°F), an average of 31°C (88°F), and a maximum reaching 43°C (110°F). Precipitation significantly increases to 54 mm (2.1 in) spread over ten days, and humidity drops slightly to 34%. These differences highlight how May is drier and cooler compared to the hotter and wetter conditions of July. For more details, check out Tucson weather in July.

May and August present contrasting weather patterns. In May, temperatures range from a mild 9°C (48°F) at night to a warm 40°C (104°F) during the day, with low humidity at 40% and minimal rainfall of just 3 mm (0.1 in) over only one day. In comparison, August is noticeably warmer, featuring a minimum temperature of 20°C (69°F) and soaring to a maximum of 42°C (108°F), accompanied by increased humidity at 48% and a significant rise in precipitation to 35 mm (1.4 in) spread over eight days. For more details on the climate during this month, you can visit Tucson weather in August.

The weather in May is typically warmer, with average temperatures ranging from a min of 9°C (48°F) to a max of 40°C (104°F), while September sees slightly cooler temperatures, with a minimum of 13°C (56°F) and a maximum of 41°C (106°F). May features very little precipitation, averaging just 3 mm (0.1 in) over a single day, resulting in lower humidity levels at 40%. In contrast, September experiences a notable increase in rainfall, with averages of 27 mm (1.1 in) over three days, leading to higher humidity levels of 64%. For more specific insights into September weather patterns, check out Tucson weather in September.

May and October showcase striking differences in weather patterns. In May, temperatures can reach a high of 40°C (104°F), with an average of 25°C (78°F) and relatively low humidity levels at 40%. The month experiences minimal rainfall, averaging only 3 mm (0.1 in) over about 1 day. In contrast, October brings cooler temperatures, with a maximum of 38°C (100°F) and an average of 23°C (73°F). This month also experiences increased humidity at 67% and more precipitation, totaling 10 mm (0.4 in) over approximately 2 days. For more detailed insights, check out Tucson weather in October.

May and November present strikingly different weather patterns. In May, temperatures can soar as high as 40°C (104°F) with an average of 25°C (78°F), and the month experiences very little precipitation, averaging just 3 mm (0.1 in) over only one day. The humidity is relatively low at 40%, creating a warm and dry atmosphere. In contrast, November features much cooler temperatures, ranging from a minimum of 2°C (36°F) to a comfortable average of 17°C (64°F), with a maximum of 33°C (91°F). The month is wetter, with 14 mm (0.6 in) of precipitation, though it also sees rain on just one day. Additionally, November has a significantly higher humidity level of 77%, contributing to a more humid feel compared to May. For more details, you can check Tucson weather in November.

May and December present contrasting weather patterns. In May, temperatures soar, with an average of 25°C (78°F) and maximums reaching up to 40°C (104°F), while precipitation is minimal at just 3 mm (0.1 in) over only one day, resulting in a low humidity of 40%. In stark contrast, December offers much cooler conditions, featuring temperatures that range from a minimum of -2°C (29°F) to a maximum of 27°C (80°F), coupled with more frequent rainfall amounting to 27 mm (1.0 in) across four days, leading to increased humidity levels of 82%. For more detailed information, you can check Tucson weather in December.

Compare Tucson's Climate with Cities Worldwide

Conclusion: What to Expect From May Weather in Tucson

As May unfolds in Tucson, the temperature begins to rise, giving a taste of the summer heat that lies ahead. With daily averages hovering around a comfortable 25°C (78°F), this month stands out as a transition period, where the peak temperatures can soar to a sweltering 40°C (104°F), yet the nights remain pleasantly mild. Unlike the more temperate spring months, May typically experiences minimal precipitation, with just about 3 mm (0.1 in) of rain across a single day, marking it as one of the driest times of the year. The humidity levels stabilize around 40%, offering a dry heat that many find enjoyable. For more insights into Tucson's climate throughout the year, visit Tucson Climate.