Last updated: February 24, 2025
In August, Portsmouth experiences a delightful summer climate, with average temperatures hovering around 22°C (71°F) and peaking at a warm 31°C (88°F). The nights can be refreshingly cool, dipping down to a minimum of 13°C (55°F). Visitors should be prepared for some rain, as the month sees approximately 71 mm (2.8 in) of precipitation across about 9 days. With a humidity level of 66%, the air can feel quite comfortable, making it an ideal time for outdoor activities and enjoying the vibrant local scene.
In August, Portsmouth experiences some of its warmest temperatures, with minimums typically around 13°C (55°F) and averages rising to a comfortable 22°C (71°F). The maximums can reach up to 31°C (88°F), making it a favorable time for outdoor activities and enjoying the waterfront. This month mirrors July’s warmth, maintaining a steady climate that invites both locals and tourists to savor the season. As summer peaks, the pleasant temperatures mark a stark contrast to the icy depths of winter, where January's frigid lows plunge to -19°C (-2°F). Overall, August serves as a brief yet delightful reprieve before the coolness of autumn begins to encroach.
In August, Portsmouth experiences a notable dip in precipitation, receiving just 71 mm (2.8 in) of rainfall over approximately 9 days. This lower total is part of a trend seen during the summer months, where July peaks with 123 mm (4.8 in), while August’s drier conditions suggest a gradual shift towards the fall season. Despite the reduced rainfall, August’s precipitation is still slightly higher than the preceding months of May and June, indicating a balanced climate as the city transitions. As September approaches, the anticipated increase in precipitation to 78 mm (3.1 in) reflects a return to the wetter patterns typical of early autumn, setting the stage for a variety of seasonal changes.
In August, humidity in Portsmouth, United States, dips to 66%, marking the lowest point of the year. This decline represents a notable trend from the 86% humidity of January, gradually decreasing as the seasons shift. After enjoying slightly drier conditions in July, August's humidity continues the downward trajectory, paving the way for the more comfortable, yet slightly increasing humidity levels that return in September at 71%. Overall, these patterns highlight a seasonal transition, where the summer heat gives way to a gradual return of moisture in the air, ultimately creating a refreshing respite before autumn settles in.
In August, Portsmouth experiences a very high UV Index of 9, maintaining the intensity of the summer months with a quick burn time of just 15 minutes. This trend reflects a peak in sun exposure risk, matching the UV levels seen in July and May, which are also noted for their intense sunlight. As the summer draws to a close, it's crucial for residents and visitors alike to take protective measures against harmful UV rays, especially during peak hours. Transitioning into September, the UV Index drops to 7, signaling a gradual decrease in sun intensity as fall approaches. Stay informed about local UV conditions to protect your skin and enjoy the outdoors safely. For more details, visit Portsmouth UV Index.
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In August, Portsmouth basks in the glorious sun, marking its sunniest month with an impressive 337 hours of sunlight. This peak follows a steady ascent in sunshine from the chilly depths of January, where only 150 hours are recorded, through the blossoming spring months of March and April. Notably, summer reigns supreme as June and July contribute 330 and 335 hours respectively, creating a warm ambiance that enhances outdoor activities and community gatherings. As August gently transitions into September, the sunshine begins to taper off, yet the lingering warmth of summer still holds a prominent place in the hearts of locals.
August in Portsmouth sees a notable dip in sunny weather, with only a 32% chance of sun—the same as in July and December. This marks a peak period of low sunlight compared to the rest of the year, reflecting a trend where summer months often prioritize humidity over clarity. Interestingly, while March boasts the highest likelihood of brightness at 61%, August's figures align more closely with the gloomy winter months than the sunnier spring and fall periods that follow. As the summer wanes, residents and visitors may find themselves longing for those sun-soaked days of early spring and late summer, where the skies are often more favorable.
In August, Portsmouth enjoys a delightful 13 hours of daylight, seamlessly transitioning from the peak brightness of June when the days stretch to 15 hours. As summer winds down, the gradual reduction in daylight is evident, following a trend that peaks mid-year. While July retains a similar duration, August signals a subtle reminder of the approaching autumn. This pattern continues into September, where daylight shrinks to 12 hours, further emphasizing the shift in seasons. Overall, the progression of daylight reflects Portsmouth's vibrant seasonal changes, inviting residents to make the most of the sun-soaked days before the shortening hours of fall set in.
In August, the winds in Portsmouth, United States, experience a notable lull, with an average speed of just 3.3 m/s (7 mph), marking the lowest point of the year. This gentle breeze contrasts sharply with the more robust currents of earlier months, particularly March, which sees a peppy average of 5.2 m/s (12 mph). As summer peaks, the wind speed gradually dwindles, reflecting a transition into the softer, warmer days of late summer. However, this dip is temporary, as September brings a slight resurgence with winds picking up to 3.9 m/s (9 mph). The overall trend suggests a dynamic wind pattern throughout the year, where the summer months feature the mildest breezes, inviting a sense of calm that many residents and visitors cherish.
The weather in Portsmouth changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of August's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Portsmouth and find detailed weather information for every month.
August and January present contrasting weather experiences. In August, temperatures range from a mild 13°C (55°F) to a warm 31°C (88°F), accompanied by an average temperature of 22°C (71°F) and relatively moderate humidity at 66%. This month sees about 71 mm (2.8 in) of precipitation over approximately 9 days, making it a more pleasant time for outdoor activities.
In sharp contrast, January features significantly colder temperatures, with a minimum of -19°C (-2°F) and a maximum of 17°C (64°F), leading to an average of -1°C (30°F). The humidity remains high at 86%, and precipitation measures around 79 mm (3.1 in) over 8 days, often falling as snow. For more details on January weather, you can check Portsmouth weather in January.
August and February present stark contrasts in weather. In August, temperatures range from a minimum of 13°C (55°F) to a maximum of 31°C (88°F), with an average of 22°C (71°F). The month sees about 71 mm (2.8 in) of precipitation over 9 days and maintains a humidity level of 66%. In contrast, February experiences a much colder climate, with temperatures dipping as low as -16°C (4°F) and only reaching a maximum of 17°C (64°F), averaging around 0°C (32°F). This month typically receives 98 mm (3.9 in) of precipitation spread over 11 days, accompanied by higher humidity at 84%. For a closer look at February conditions, visit Portsmouth weather in February.
The weather in August is characterized by warm temperatures, with a minimum of 13°C (55°F) and an average of 22°C (71°F), peaking at a comfortable 31°C (88°F). In contrast, March experiences significantly colder conditions, with temperatures ranging from a chilling -14°C (8°F) to a maximum of 17°C (63°F), and an average of just 2°C (36°F). While August sees 71 mm (2.8 in) of precipitation over 9 days, March is wetter, with 94 mm (3.7 in) over 10 days, along with higher humidity levels at 82%. For a detailed look at March weather, check out Portsmouth weather in March.
In comparing the weather of August and April, a marked contrast can be observed. August features a much warmer climate, with average temperatures ranging from a mild 22°C (71°F) to a high of 31°C (88°F), alongside relatively lower precipitation at 71 mm (2.8 in) over 9 days and humidity levels at 66%. In contrast, April experiences significantly cooler temperatures, with averages between -2°C (29°F) and a maximum of 24°C (76°F). However, it sees more rainfall, totaling 143 mm (5.6 in) over 13 days, and higher humidity levels at 80%. For a closer look at the specifics of April weather in Portsmouth, check out Portsmouth weather in April.
When comparing the weather in August and May, it’s clear that August is generally warmer and more consistent in temperature. In August, temperatures range from a minimum of 13°C (55°F) to a maximum of 31°C (88°F), with an average of 22°C (71°F), while May sees cooler temperatures that span from 2°C (37°F) to a maximum of 27°C (82°F), with an average of 13°C (55°F). Additionally, August experiences slightly less precipitation at 71 mm (2.8 in) over 9 days, compared to May's 83 mm (3.3 in) over 11 days. Humidity levels are also marginally lower in August at 66%, compared to 72% in May, making August generally feel warmer and drier overall. For a more detailed look at May weather specifics, you can visit Portsmouth weather in May.
In comparing the weather of August and June, August generally boasts warmer temperatures, with an average of 22°C (71°F) compared to June's average of 18°C (65°F). While both months experience similar maximum temperatures—31°C (88°F) in August and 30°C (86°F) in June—August tends to be slightly drier, receiving 71 mm (2.8 in) of precipitation over 9 days versus June's 88 mm (3.5 in) over 10 days. Humidity levels are comparable, with August at 66% and June slightly higher at 72%. For more detailed weather information, you can check Portsmouth weather in June.
In comparing the weather between July and August, we observe that both months experience similar temperature ranges, with minimums around 13°C (55°F), average temperatures of 22°C (71°F), and maximums reaching 31°C (88°F). However, August tends to be slightly drier, receiving just 71 mm (2.8 inches) of precipitation over 9 days compared to July's 123 mm (4.8 inches) over 12 days. Additionally, humidity levels are fairly consistent, with August registering at 66% and July at 67%. For a detailed look at July's weather, you can check out Portsmouth weather in July.
August and September present a distinct shift in weather conditions. August boasts warmer temperatures, with a minimum of 13°C (55°F) and an average of 22°C (71°F), reaching a peak of 31°C (88°F). In contrast, September experiences cooler weather, dropping to a minimum of 7°C (46°F) and averaging 18°C (65°F), while still reaching a maximum of 30°C (86°F). While August sees 71 mm (2.8 in) of precipitation over 9 days, September's rainfall slightly increases to 78 mm (3.1 in) over 8 days. Humidity remains comparable, with August at 66% and September rising to 71%. For more details on weather specifics, you can check Portsmouth weather in September.
August and October exhibit strikingly different weather patterns. In August, temperatures range from a minimum of 13°C (55°F) to a maximum of 31°C (88°F), with an average of 22°C (71°F). The month experiences about 71 mm (2.8 in) of precipitation over nine days, while humidity levels hover around 66%. In contrast, October sees a significant drop in temperatures, with a minimum of 1°C (34°F) and a maximum of 25°C (78°F), averaging 13°C (56°F). The month is wetter, receiving approximately 142 mm (5.6 in) of rainfall over eleven days and higher humidity at 78%. For more detailed information, you can check Portsmouth weather in October.
August and November showcase strikingly different weather patterns. August generally features warmer temperatures, with minimums around 13°C (55°F) and maximums reaching up to 31°C (88°F), while November's temperatures drop significantly, starting as low as -12°C (11°F) and peaking at 20°C (69°F). Precipitation is also more pronounced in November, totaling 108 mm (4.3 in) over 11 days, compared to August's 71 mm (2.8 in) over 9 days. Additionally, November tends to have higher humidity at 84%, contrasting with August's 66%. For more detailed information about the weather in November, visit Portsmouth weather in November.
August and December present stark contrasts in weather conditions. In August, temperatures range from a comfortable minimum of 13°C (55°F) to a warm maximum of 31°C (88°F), accompanied by moderate humidity levels of 66% and relatively low precipitation of 71 mm (2.8 in) over 9 days. In contrast, December features much colder temperatures, with a minimum of -19°C (-1°F) and a maximum of 15°C (59°F), while experiencing higher humidity at 81% and a significant increase in precipitation to 133 mm (5.2 in) over 10 days. For more detailed insights, check out Portsmouth weather in December.
August in Portsmouth stands out as a warm and vibrant month, marked by a pleasant blend of high temperatures and relatively humid conditions. Unlike the cooler months of spring and autumn, August often sees the mercury soar, peaking at tropical levels that beckon outdoor activities. While rain graces the area on several days, the total precipitation remains moderate, contributing to the lushness of the landscape without dampening the summer spirit. As summer begins to fade, the combination of warmth and humidity makes August uniquely lively, setting it apart from the milder, crisper months that follow. For a deeper insight into what to expect throughout the year, visit Portsmouth Climate.