Last updated: February 24, 2025
September in Galveston, United States, combines warm temperatures and varied precipitation, making it a notable month for weather enthusiasts. With a maximum of 32°C (89°F) and an average of 27°C (81°F), the warmth provides a pleasant atmosphere for outdoor activities. However, visitors should be prepared for rain, as the area experiences 243 mm (9.6 in) of precipitation over approximately 16 days. The humidity level averages around 75%, contributing to a tropical feel in the air. Whether you're exploring the coastline or enjoying local festivals, September's weather in Galveston is both vibrant and dynamic.
In September, Galveston enjoys pleasant warm weather as summer begins to wane, with temperatures ranging from a minimum of 20°C (68°F) to a cozy average of 27°C (81°F), reaching highs of 32°C (89°F). This month marks a shift from the intense heat of July and August, when temperatures consistently soar. As the days grow shorter and the humidity slightly decreases, it becomes an ideal time for outdoor activities and beach outings. The comfortable warmth in September prepares the way for the cooler months ahead, making it a delightful transition in Galveston’s climate.
In September, Galveston experiences a significant uptick in precipitation, averaging 243 mm (9.6 in) over 16 days of rain, making it one of the wettest months of the year. This dramatic increase follows a notably dry period in March and April, where rainfall barely exceeded 58 mm (2.3 in) and 86 mm (3.4 in), respectively. The transition from summer to fall brings not only heavier rains but also an expansion in the number of rainy days compared to the summer months, illustrating the onset of the tropical storm season. With September's rainfall outpacing even the preceding months—August recorded 210 mm (8.3 in)—it's clear that this coastal city prepares for the lush vibrancy that often follows such abundant precipitation.
In September, Galveston experiences a slight increase in humidity, averaging around 75%. This marks a subtle recovery from the drier months of summer, where July and August saw their lowest levels at 74% and 73% respectively. As the year progresses from the sweltering heat of the summer to the cooler fall months, September's humidity remains relatively moderate compared to the onset of winter, where levels begin to rise again, peaking at 83% in December. This trend reveals a climate that is characteristic of coastal regions, where humidity ebbs and flows, influenced by seasonal transitions and weather patterns.
As September rolls into Galveston, the UV Index remains consistently high, peaking at 11, which places it in the extreme exposure category—similar to the preceding summer months. This means that residents and visitors should be particularly cautious, with a burn time of only 10 minutes for unprotected skin. While July and August saw a peak UV Index of 12, September signals a slight dip, though the intensity is still significant enough to warrant protective measures. As the season shifts towards October, the UV Index is expected to decrease further to 9, translating to a very high exposure category with longer burn times. For more detailed insight into the UV Index trends throughout the year, check out Galveston UV Index.
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September in Galveston exhibits a delightful transition as summer begins to wane, offering 275 hours of sunshine. This marks a slight decrease from the sun-drenched peaks of the previous months; July and August shine with 327 and 323 hours respectively. However, September's ample sunshine still embodies the lingering warmth, making it a perfect time for beachgoers to soak up the sun before autumn fully arrives. As daylight gradually dwindles into the cooler months, the sun-soaked days of summer give way to a more temperate climate, while October welcomes back 283 hours of sunlight, hinting at the beauty of fall by the Gulf. Overall, the monthly sunshine trend highlights a gradual yet comforting shift from the vibrant brightness of summer to the more mellow tones of the upcoming season.
In Galveston, September marks a notable shift in weather patterns, with a 47% chance of sunny days—one of the higher probabilities for the year. As the summer months wind down, the likelihood of basking in the sun increases, bouncing back from the notably lower chances seen in July and August. This resurgence hints at a transition towards the more favorable conditions that October and November promise, which boast even better odds of sunshine at 51% and 58%, respectively. September's sunny prospects make it a delightful time to enjoy outdoor activities before the autumn chill sets in, providing a perfect blend of warmth and light.
As summer fades, September in Galveston brings a gentle shift in daylight duration, offering about 12 hours of sunlight. This marks a subtle decline from the consistent 13 hours seen during the peak summer months from May to August. The tapering of daylight serves as a reminder of the approaching autumn, where sunlight gradually diminishes, with October bringing just 11 hours and November further reducing daylight to 10 hours. This rhythm of changing light mirrors the seasonal transition, inviting residents and visitors alike to cherish the lingering warmth before the shorter days set in.
In September, Galveston experiences a notable shift in wind patterns, with an average speed of 4.8 m/s (11 mph). This marks a slight increase from the summer months, which saw some of the lowest winds of the year in July and August. Despite the improvement, September still maintains a calmer breeze compared to the earlier spring months, where winds peaked around 6.5 m/s (15 mph) in May. As the season transitions into October, a gradual uptick to 5.0 m/s (11 mph) suggests a potential for more refreshing gusts, hinting at an invigorating change in the coastal atmosphere as autumn approaches.
The weather in Galveston changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of September's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Galveston and find detailed weather information for every month.
September and January present stark contrasts in weather patterns. In September, temperatures are warm, with a minimum of 20°C (68°F) and an average high of 32°C (89°F), accompanied by significant precipitation of 243 mm (9.6 in) over 16 days, leading to high humidity levels around 75%. In contrast, January experiences much cooler temperatures, with a minimum of -2°C (29°F) and an average around 14°C (57°F). Precipitation is notably lower at 90 mm (3.6 in) across just 9 days, while humidity slightly increases to 79%. For a detailed look at the weather conditions during this time, check out Galveston weather in January.
September and February showcase stark contrasts in weather. September is characterized by warm temperatures, with a minimum of 20°C (68°F) and an average of 27°C (81°F), peaking at a hot 32°C (89°F). The month also sees considerable rainfall, with 243 mm (9.6 in) spread over 16 days, resulting in a humidity level of 75%. In contrast, February experiences much cooler conditions, with temperatures ranging from a brisk minimum of -6°C (22°F) to a milder average of 15°C (59°F) and a maximum of 21°C (71°F). Precipitation is less frequent, totaling 88 mm (3.4 in) across 13 days, and the humidity rises slightly to 80%. For more details about February weather, you can check this link: Galveston weather in February.
September and March present contrasting weather patterns. In September, the temperatures are notably warmer, with minimums around 20°C (68°F) and average highs reaching 32°C (89°F). The month is also characterized by higher precipitation levels, totaling 243 mm (9.6 in) over approximately 16 wet days, alongside a humidity rate of 75%. Conversely, March brings cooler temperatures, with minimums dropping to 3°C (38°F) and an average of 18°C (65°F), peaking at a comfortable 24°C (76°F). Precipitation is significantly lower, averaging 58 mm (2.3 in) over just 8 days, with a slightly higher humidity at 78%. For more specific details on March conditions, you can check Galveston weather in March.
When comparing the weather in September and April, September tends to be much warmer and wetter. September boasts a minimum temperature of 20°C (68°F) and an average of 27°C (81°F), reaching a maximum of 32°C (89°F). In contrast, April has cooler temperatures, with a minimum of 10°C (51°F), an average of 21°C (70°F), and a maximum of 27°C (82°F). Additionally, September experiences significantly more precipitation, with 243 mm (9.6 in) over 16 days, while April sees only 86 mm (3.4 in) over 10 days. Humidity levels are quite similar, with September at 75% and April slightly higher at 81%. For more details on April weather, check out Galveston weather in April.
September weather tends to be warmer than May, with average temperatures reaching 27°C (81°F) compared to May's 25°C (77°F). The maximum temperatures in September can soar up to 32°C (89°F), while May peaks at 29°C (85°F). However, September experiences significantly more precipitation, averaging 243 mm (9.6 in) over about 16 days, while May sees 164 mm (6.5 in) across 12 days. Humidity levels are slightly higher in September at 75%, compared to 79% in May. For more specific information, you can check Galveston weather in May.
In comparing the weather of September and June, both months share similar average temperatures, with September's average at 27°C (81°F) and June also at 27°C (82°F). However, June tends to be slightly warmer at night with a minimum temperature of 23°C (74°F) compared to September's cooler 20°C (68°F). When it comes to precipitation, September sees a significant increase with 243 mm (9.6 in) over 16 days, while June has less rainfall at 170 mm (6.7 in) across 13 days. Interestingly, both months maintain a consistent humidity level of 75%. For a more detailed look at the weather in June, you can visit Galveston weather in June.
When comparing the weather in September and July, it's clear that both months experience warm temperatures, though September tends to be slightly cooler. In September, the minimum temperature averages around 20°C (68°F), with a maximum of 32°C (89°F), while July typically has a minimum of 24°C (76°F) and a maximum of 33°C (91°F). Precipitation also differs between the two months; September sees more rain, with 243 mm (9.6 in) over 16 days, compared to July's 151 mm (5.9 in) over 14 days. Humidity levels are quite similar, hovering around 75% in September and 74% in July. For more details on July's weather, check out Galveston weather in July.
In comparing the weather of September and August, we find that September experiences slightly cooler temperatures, with a minimum of 20°C (68°F) compared to August's 24°C (75°F). The average temperature in September is 27°C (81°F), which is marginally lower than August's average of 29°C (84°F). Both months share the same maximum temperature of 32°C (89°F), but September has more precipitation, totaling 243 mm (9.6 in) over 16 days, while August sees less, at 210 mm (8.3 in) over 18 days. Additionally, September's humidity is higher, at 75%, compared to August's 73%. For more details, check out Galveston weather in August.
In September, the weather is notably warmer, with average temperatures hovering around 27°C (81°F) and maximum highs reaching up to 32°C (89°F). This month is also characterized by significant rainfall, totaling 243 mm (9.6 in) over 16 days, while humidity remains high at 75%. In contrast, October brings a marked cooling trend, with average temperatures dipping to 24°C (76°F) and maximums peaking at 29°C (85°F). Precipitation is reduced to 150 mm (5.9 in) over 12 days, maintaining the same humidity level. For more details on the weather specifics in October, visit Galveston weather in October.
In September, the weather is warm and humid, with average temperatures ranging from a comfortable 20°C (68°F) at night to a hot 32°C (89°F) during the day. This month experiences significant rainfall, with 243 mm (9.6 in) over 16 days. In contrast, November brings a noticeable shift in temperature, where nights can be quite cool with a minimum of 5°C (41°F), while daytime highs reach a pleasant 25°C (78°F). Additionally, November sees much less precipitation, totaling only 77 mm (3.0 in) over 9 days, and humidity remains relatively high at 79%. For more detailed information about November’s weather patterns, you can visit Galveston weather in November.
In September, the weather is typically warm and humid, with temperatures ranging from a minimum of 20°C (68°F) to a maximum of 32°C (89°F), averaging around 27°C (81°F). This month also experiences significant rainfall, with 243 mm (9.6 in) of precipitation over approximately 16 days, contributing to a humidity level of 75%. In contrast, December brings a cooler and drier climate, where temperatures range from a minimum of 4°C (40°F) to a maximum of 23°C (74°F), with an average of 16°C (61°F). Precipitation decreases to 104 mm (4.1 in) over just 10 days, and humidity rises slightly to 83%. For more specifics on December weather, visit Galveston weather in December.
As September rolls in, Galveston experiences a unique transition in weather that sets it apart from other months. Temperatures remain warm with averages around 27°C (81°F), perfect for enjoying the beach before the cooler autumn air sets in. However, the month also brings noticeable humidity and a significant increase in rainfall, with nearly half the days seeing precipitation. This combination of warmth and wetness makes September a time of fluctuating weather patterns, contrasting sharply with the drier, hotter summer months and laying the groundwork for the mild, crisp days ahead. For more insights on Galveston's weather patterns, visit Galveston Climate.