Last updated: February 24, 2025
May in Key Biscayne offers a delightful tropical climate, characterized by warm temperatures and considerable humidity. Daily highs can soar to 31°C (88°F), while the average temperature remains a comfortable 26°C (79°F). The month is marked by frequent rain, with 161 mm (6.3 in) of precipitation spread over 18 days, contributing to a lush, verdant atmosphere. Despite the showers, the average humidity level of 71% enhances the island's vibrant flora, making this a beautiful time to experience the scenic charm of Key Biscayne.
In May, Key Biscayne begins to embrace the warmth of summer, with temperatures steadily rising. The month kicks off with a minimum temperature of 19°C (66°F), climbing to a pleasant average of 26°C (79°F), and peaking at 31°C (88°F). This marks a noticeable transition from the milder conditions of April, as residents and visitors alike enjoy the increasing warmth and sunny days. As the month progresses, the heat intensifies, establishing a pattern that signals the approach of summer, setting the perfect stage for outdoor activities and beachfront relaxation. Whether lounging by the shore or exploring the vibrant local culture, May's inviting temperatures create an ideal backdrop for enjoying everything this beautiful coastal town has to offer.
May marks a notable shift in precipitation patterns for Key Biscayne, with a significant increase in rainfall, totaling 161 mm (6.3 in)—more than double that of April's 63 mm (2.5 in). This surge aligns with the 18 rainy days in the month, setting the stage for one of the wettest periods of the year. As summer approaches, the data highlights a trend of escalating precipitation, with both June and July expected to exceed May's totals, reaching 172 mm (6.8 in) and 173 mm (6.8 in), respectively. This consistent uptick indicates a transition into a rainier season, providing much-needed moisture to the vibrant ecosystem while also reminding residents to stay prepared for the wet weather ahead.
In May, Key Biscayne experiences a decline in humidity, averaging 71%, marking the onset of a more comfortable atmosphere as spring transitions to summer. This slight decrease follows a steady drop from January's 81% and April's 73%, highlighting a trend towards lower humidity as the year progresses. June brings even less humidity, dipping to 69%, indicating a shift toward warmer, drier days. Overall, May serves as a bridge in the cyclical pattern of humidity in Key Biscayne, where residents and visitors alike can savor the pleasantness before the summer heat fully sets in.
May in Key Biscayne, United States, marks a peak in UV intensity, continuing the trend established in April. With a UV Index of 12, classified as extreme, sun exposure becomes increasingly perilous, allowing just 10 minutes before the risk of burns escalates significantly. As the weather warms, this pattern is consistent, with similar UV levels carried through to June and July. Awareness of this intensity is vital—protective measures are essential to enjoy the sunny days while minimizing skin damage. For a detailed view of UV patterns throughout the year, visit Key Biscayne UV Index.
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As May unfolds in Key Biscayne, the sun continues to shine brightly, boasting an impressive 325 hours of sunshine. Following a bustling April with 336 hours, the days in May remain delightful for outdoor enthusiasts and beachgoers alike. While the sunlight slightly dips in preparation for the summer, it still outshines earlier months like January and February. The trend for the first half of the year shows a gradual increase in sunshine hours, peaking in July at 344 hours. This consistent pattern emphasizes Key Biscayne's allure as a sun-soaked destination, making every month an inviting experience for sun-seekers and nature lovers.
In Key Biscayne, May brings a moderate 48% chance of sunny weather, continuing a trend of relatively bright days that started earlier in the year. Following a promising February with a 60% sunshine probability and a consistent performance through March (55%) and April (54%), May stands out as a transitional month. While the likelihood of sun dips slightly from the spring, it remains significantly higher than the sweltering summer months ahead, where the chances plummet to around 15% in June and 19% in July. This pattern suggests that while May may not be the bestselling sunny month, it captures a crucial window for outdoor activities before the heat and humidity take center stage.
In Key Biscayne, United States, May marks a delightful transition into the year’s sunniest days, offering 13 hours of daylight that can invigorate any outdoor enthusiast. This month stands as a highlight in the annual cycle, reflecting a peak that begins in April with 12 hours and is sustained through June, reinforcing the region's vibrant spring atmosphere. Following May, daylight gradually begins to wane, reducing to 12 hours in August and ebbing further into the autumn months. This gradual increase from just 10 hours in January to a lush 13 hours in May underscores an inviting pattern of extended daylight that enhances the beauty and vitality of the season. As summer unfolds, the consistent daylight hours provide ample opportunities for exploration, recreation, and relaxation under the warm Florida sun.
In Key Biscayne, the month of May brings a gentle breeze with an average wind speed of 4.6 m/s (10 mph), a slight increase from April's 4.4 m/s. This reflects a trend of gradually warmer spring times, where wind speeds peak before the summer heat. Following May, the winds begin to taper off into the summer months, hitting a low of 3.1 m/s (7 mph) in July. Notably, February and March exhibit a similar wind strength, both at 4.9 m/s (11 mph), indicating a consistent breeze during the transitional phase into spring. As the year progresses into the fall, the winds continue to decline, with September recording the calmest conditions at just 2.4 m/s (5 mph). This beautifully showcases the dynamic weather patterns in Key Biscayne, making May an ideal month for outdoor enthusiasts enjoying both the warmth and moderate winds.
The weather in Key Biscayne 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 Key Biscayne and find detailed weather information for every month.
When comparing the weather in May and January, it’s clear that May is significantly warmer, with average temperatures reaching 26°C (79°F) and maximums climbing to 31°C (88°F). In contrast, January sees milder conditions, with an average temperature of 21°C (70°F) and a maximum of 28°C (83°F). May also experiences much higher precipitation, averaging 161 mm (6.3 in) over 18 days, while January is relatively dry with only 34 mm (1.3 in) across 6 days. Despite the lower temperatures, January has slightly higher humidity at 81%, compared to May’s 71%. For more detailed information, check out Key Biscayne weather in January.
May generally presents warmer temperatures in Key Biscayne compared to February, with minimums of 19°C (66°F) rising to a maximum of 31°C (88°F), whereas February exhibits milder temperatures ranging from 10°C (51°F) to 28°C (83°F). Precipitation levels also differ significantly; May sees a total of 161 mm (6.3 in) over 18 days, while February has a much lighter rainfall of 50 mm (2.0 in) across just 9 days. Additionally, February features a slightly higher humidity level at 79%, compared to May's 71%. For those interested in detailed February weather insights, check out Key Biscayne weather in February.
When comparing the weather in March and May, it's clear that May tends to be warmer and wetter. May features minimum temperatures around 19°C (66°F) and averages reaching 26°C (79°F), with maximum highs of 31°C (88°F). In contrast, March has cooler temperatures, with a minimum of 12°C (54°F) and an average of 23°C (73°F), peaking at 30°C (86°F). Additionally, May experiences significantly more precipitation, with 161 mm (6.3 in) spread over 18 days, compared to March's much lighter 30 mm (1.2 in) over just 5 days. Humidity levels also differ slightly, with May at 71% and March a bit higher at 76%. To explore more about the weather during March, you can check this link: Key Biscayne weather in March.
In comparing the weather patterns of April and May, May tends to be warmer overall, with average temperatures reaching 26°C (79°F) compared to April's 25°C (77°F). However, April boasts a slightly cooler maximum temperature of 32°C (90°F), while May has a maximum of 31°C (88°F). Precipitation is notably higher in May, with 161 mm (6.3 in) over 18 days, compared to April's 63 mm (2.5 in) over 11 days, indicating that May is typically wetter and more humid, with an average humidity of 71% compared to April's 73%. For a closer look at the specific weather conditions during April, you can visit Key Biscayne weather in April.
In comparing the weather between May and June, it is evident that June experiences slightly warmer temperatures, with minimums rising from 19°C (66°F) in May to 24°C (75°F) in June. The average temperature also sees a modest increase from 26°C (79°F) in May to 28°C (82°F) in June, peaking at 32°C (90°F) compared to May's maximum of 31°C (88°F). Precipitation is also a notable factor; while May receives 161 mm (6.3 in) over 18 days, June sees a bit more rain with 172 mm (6.8 in) across 22 days. Humidity levels remain relatively consistent, slightly decreasing from 71% in May to 69% in June. For more specific insights into weather patterns, you can check Key Biscayne weather in June.
In comparing the weather between May and July, we can see some notable differences. May typically experiences a minimum temperature of 19°C (66°F) and an average of 26°C (79°F), peaking at a maximum of 31°C (88°F), with a higher precipitation level of 161 mm (6.3 in) over 18 rainy days and an average humidity of 71%. In contrast, July is warmer, with minimum temperatures of 24°C (76°F) and an average of 28°C (83°F), reaching a maximum of 33°C (92°F). However, it sees increased rainfall, with 173 mm (6.8 in) spread over 26 days, while maintaining a slightly lower humidity level of 70%. For more detailed information, you can check Key Biscayne weather in July.
May and August both feature warm temperatures, but August tends to be slightly hotter and more humid. In May, temperatures range from a minimum of 19°C (66°F) to a maximum of 31°C (88°F), with an average of 26°C (79°F), while August sees temperatures starting at 25°C (76°F) and peaking at 32°C (90°F) for an average of 28°C (83°F). Precipitation is more frequent in both months, with May receiving 161 mm (6.3 in) over 18 days and August experiencing 181 mm (7.1 in) over 25 days. The humidity remains relatively consistent, hovering around 71% in May and increasing slightly to 72% in August. For a more detailed look at conditions during this time, check out Key Biscayne weather in August.
May and September showcase warm temperatures, but September tends to be slightly hotter, with average highs reaching 33°C (91°F) compared to May's 31°C (88°F). The minimum temperatures in September are also higher, starting at 24°C (75°F) versus May's 19°C (66°F). However, September experiences more precipitation, totaling 203 mm (8.0 in) over 22 days, compared to May's 161 mm (6.3 in) over 18 days. Additionally, humidity on average is higher in September at 76% compared to 71% in May. For a detailed look at September conditions, you can visit Key Biscayne weather in September.
In comparing the weather of May and October, we see notable similarities and differences. May typically experiences warmer temperatures with a minimum of 19°C (66°F) and an average of 26°C (79°F), whereas October has slightly cooler temperatures with a minimum of 15°C (59°F) but a similar average of 27°C (81°F). Both months have comparable maximum temperatures, with May reaching up to 31°C (88°F) and October peaking at 30°C (87°F). Precipitation levels are nearly identical, with May averaging 161 mm (6.3 in) over 18 rain days, and October slightly lower at 157 mm (6.2 in) over 22 rain days. The humidity rises in October to 79% compared to May’s 71%. For more detailed insights on October weather, you can visit Key Biscayne weather in October.
May and November showcase distinct weather patterns, reflecting the transition from spring to late autumn. In May, temperatures range from a minimum of 19°C (66°F) to a maximum of 31°C (88°F), with an average of 26°C (79°F). This month also sees higher precipitation at 161 mm (6.3 in) over 18 days, contributing to a humidity level of 71%. In contrast, November features cooler temperatures, with a minimum of 12°C (54°F) and a maximum of 30°C (86°F), averaging 24°C (76°F). The month is drier, with only 93 mm (3.7 in) of rainfall across 14 days and an increased humidity of 80%. For more detailed insights, you can visit Key Biscayne weather in November.
In May, the weather tends to be warmer and more humid, with average temperatures ranging from a minimum of 19°C (66°F) to a maximum of 31°C (88°F). During this month, precipitation is significant, averaging 161 mm (6.3 in) over about 18 days, resulting in a humidity level of 71%. In contrast, December offers a cooler and drier climate, with temperatures ranging from a minimum of 11°C (51°F) to a maximum of 29°C (84°F). Precipitation drops substantially to 41 mm (1.6 in) over just 9 days, alongside increased humidity at 81%. For more detailed information, you can check out Key Biscayne weather in December.
As May unfolds in Key Biscayne, it heralds the transition to warmer, more humid weather, with temperatures that typically soar to a maximum of 31°C (88°F), making it noticeably warmer than the cooler spring months. While the average stays comfortable at 26°C (79°F), the increase in humidity to about 71% gives the air a stickier feel. Rainfall becomes more frequent, with 18 days seeing precipitation, contributing to a blend of sunshine and showers. This month offers a vibrant taste of summer, setting the stage for the hotter months to follow. For a deeper dive into the patterns of weather throughout the year in this beautiful locale, visit Key Biscayne Climate.