September Weather in Palouse, United States

Last updated: February 24, 2025

In September, Palouse, United States, experiences a notable range in temperatures, with a maximum reaching a sizzling 35°C (94°F) and a crisp minimum dipping to 1°C (34°F). The average temperature settles at a comfortable 16°C (61°F), making it an ideal month for outdoor activities. The region sees 32 mm (1.2 in) of precipitation over 5 days, contributing to a humidity level of 62%. This blend of warmth and occasional rain creates a refreshing backdrop for the stunning fall foliage that characterizes the season.

September Temperature in Palouse

As September rolls around in the Palouse region of the United States, temperatures begin a noticeable transition from the scorching highs of summer to the cooler embrace of autumn. The month starts with nighttime lows dipping to around 1°C (34°F), while daytime averages settle comfortably at 16°C (61°F). This gradual cooling allows for a pleasant balance, with maximum temperatures climbing to a still-warm 35°C (94°F), echoing the residue of summer heat. Compared to the extreme highs of July and August, where temperatures soared into the low 40s°C (over 100°F), September offers a gentler climate that hints at the approaching chill of fall. As the leaves begin to change, this transitional month invites outdoor activities, making it an ideal time to appreciate the vibrant landscape under a more temperate sky.

September Weather in Palouse: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Palouse, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec323139465664737261473932
Data source: Temperature data for Palouse 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.

September Precipitation in Palouse

September marks a transitional phase in the Palouse region, where precipitation begins to ramp up as summer fades. With 32 mm (1.2 inches) of rain over 5 days, it reflects a slight increase compared to the drier months of July and August, which received a negligible amount of rainfall. This uptick in precipitation sets the stage for the wetter months ahead, as October sees 76 mm (3.0 inches) anticipated. The trend highlights a shift from the season's low of just 5 mm (0.2 inches) in July to a more balanced distribution as fall approaches, signaling a refreshing change in the climate dynamic of the area.

September Precipitation Trends in Palouse

The chart displays monthly precipitation patterns in Palouse, with values for each month alongside September's data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September's conditions compare to those of other months.
JanFebMarAprMayJunJulAugSepOctNovDec811057972683451232769895
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Palouse

As summer transitions into fall, September in the Palouse marks a notable shift in humidity levels, reaching a comfortable 62%. This decline follows August's relative dryness at 64%, signaling the end of the hotter months. Throughout the year, humidity remains high in the winter months, hovering around 89% in both January and February, gradually decreasing as spring approaches. By May, levels drop to 77%, paving the way for the drier summer months when humidity hits its lowest point in August. In contrast, the humidity in October rises to 79%, hinting at the return of wetter weather as the region prepares for winter's embrace. Overall, Palouse's humidity paints a vivid picture of seasonal change, with September standing out as a transitional month towards cooler and damper conditions.

September Average Humidity in Palouse

This chart illustrates the average monthly humidity levels in Palouse, with September's data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, allowing you to see how September's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec89%89%87%84%78%78%77%64%62%79%87%90%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Palouse

As September rolls into Palouse, the UV Index shows a slight decline to 7, indicating a high exposure category and a burn time of 25 minutes. This marks a transition from the intense summer months, where values peaked at 10 in July, to a more moderate risk level. The trend throughout the year highlights how the UV Index fluctuates significantly with the seasons, with the late summer months typically experiencing the highest levels of solar intensity. As we move into fall, it's essential to remain mindful of sun safety despite the decreasing numbers. For more details on the UV Index in your area, visit Palouse UV Index.

Maximum UV Index Levels in Palouse for September

The chart shows the monthly maximum UV Index (UVI) for Palouse in September, 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.
JanFebMarAprMayJunJulAugSepOctNovDec2457891097532
Data source: Palouse September 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.

September Sunshine in Palouse

September in the Palouse region offers a delightful blend of climate and scenery, basking in an impressive 289 hours of sunshine. As summer fades, sunshine hours visibly decrease from the peak of 412 hours in July and 360 hours in June, yet this month still boasts more sunlight than several others throughout the year. The trend of gradual decline from May's 340 hours signals the shift towards autumn, but September maintains a warm and inviting atmosphere ideal for harvest season. With the days growing shorter, the region's breathtaking landscapes undergo a transformation, from vibrant greens to warm golden hues, making the last touch of summer sunlight all the more precious before the crispness of October arrives with 236 hours of sunlight.

Monthly Sunshine Duration in Palouse: September Highlighted

The September sunshine duration represents the total number of hours Palouse experiences direct sunlight during the month of September, excluding cloudy or obstructed periods. This chart compares the sunshine duration of September with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec100h144h225h277h340h360h412h357h289h236h160h115h
Data source: Palouse September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Palouse During September

As summer gracefully transitions into autumn, the likelihood of sunny weather in September in the Palouse region remains relatively high at 58%. This marks a slight decline from the summer months, where July and August boast impressive chances of sunshine at 83% and 63% respectively. Nevertheless, September continues to enjoy more sunny days than the earlier months of the year, with a significant increase seen from January's meager 22%. As the season approaches its end, September invites visitors to revel in the vibrant fall colors while still soaking up the sun, making it a delightful time to explore the natural beauty of the Palouse.

Percentage of Sunny Days in September in Palouse

The chart illustrates the percentage of sunny days in Palouse throughout the year, with September 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 Palouse experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec22%21%45%55%49%62%83%63%58%51%28%15%
Data source: Palouse September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Palouse in September

As summer fades into autumn, September in the Palouse ushers in a gentle transition with approximately 12 hours of daylight. This month marks a noticeable decline from the peak 15 hours enjoyed in June through August, illustrating the gradual shift toward shorter days. While the daylight duration still offers plenty of time for outdoor activities, it serves as a reminder of the impending fall and winter months, when daylight plummets to just 9 hours in November and 8 hours by December. Observing these transitions highlights the rhythm of nature in the Palouse, where each month crafts its own daylight narrative, urging residents to embrace the warmth of early autumn before the chill of winter sets in.

Average Daylight Hours in Palouse for September

The chart illustrates the variation in daylight duration in Palouse throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec8h 59m10h 18m11h 57m13h 38m15h 4m15h 48m15h 23m14h 6m12h 29m10h 48m9h 20m8h 34m
Data source: Palouse daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Palouse

As the summer heat gives way to the crispness of autumn, September in the Palouse experiences a gentle shift in its characteristic breezes. With an average wind speed of 2.9 m/s (7 mph), the season mirrors August's calm, maintaining a tranquil atmosphere. This slight breeze, while softer than the winds of spring and fall, accentuates the region's stunning landscapes, moving through the golden fields and rolling hills with an almost poetic grace. As the months turn, the winds begin to pick up again—October sees a modest increase to 3.1 m/s, heralding a forthcoming transition towards the blustery gusts typical of winter. The evolution of wind patterns throughout the year reflects the unique dance of seasonal changes, inviting everyone to pause and appreciate the serene beauty of the Palouse during this mesmerizing time.

Average September Wind Speed in Palouse

The chart displays monthly wind speed patterns in Palouse, with values for each month shown alongside September's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how September's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec3.33.73.33.53.43.02.62.92.9 m/s3.13.83.4
Data source: Palouse September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Palouse Compares to Other Months

The weather in Palouse 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 Palouse and find detailed weather information for every month.

In September, temperatures range from a chilly 1°C (34°F) at night to a warm 35°C (94°F) during the day, making it a month of significant variation. With an average temperature of 16°C (61°F) and only 32 mm of precipitation over about five days, September maintains a comfortable humidity level of 62%. In stark contrast, January brings much colder weather, with temperatures dropping to as low as -19°C (-2°F) and reaching a maximum of only 11°C (52°F). The average temperature is around 0°C (32°F), and January is noticeably wetter, experiencing 81 mm of precipitation over 14 days and higher humidity at 89%. To delve deeper into the specifics of January weather, you can explore Palouse weather in January.

September and February present starkly contrasting weather conditions. In September, temperatures soar from a chilly 1°C (34°F) at night to a warm average of 16°C (61°F), peaking at a high of 35°C (94°F). This month sees relatively mild precipitation of 32 mm (1.2 in) over just 5 days, with humidity levels sitting at 62%. In contrast, February experiences much harsher conditions, with temperatures dropping as low as -20°C (-5°F) and averaging around 0°C (32°F). This winter month is much wetter, recording 105 mm (4.1 in) of precipitation over 17 days and a high humidity of 89%. For those interested in specifics, see Palouse weather in February.

September weather features a wide temperature range, with minimums around 1°C (34°F) and maximums soaring to 35°C (94°F), while averaging a comfortable 16°C (61°F). The month tends to be relatively dry with only 32 mm (1.2 in) of precipitation over just five days and moderate humidity at 62%. In contrast, March presents a cooler climate with minimum temperatures plummeting to -15°C (6°F) and an average temperature of 4°C (40°F). Rainfall is considerably more frequent, totaling 79 mm (3.1 in) over 14 days, and humidity is notably higher at 87%. This stark difference highlights the transition from the warmth of late summer to the chill of early spring, making March's weather feel much more damp and brisk. For more detailed insights, you can check Palouse weather in March.

When comparing the weather in September and April, notable differences emerge in temperature and precipitation patterns. September boasts a wider temperature range, with a minimum of 1°C (34°F) and a maximum of 35°C (94°F), while April is cooler, experiencing a minimum of -6°C (22°F) and a maximum of 28°C (83°F). Precipitation is also more significant in April, with 72 mm (2.8 in) spread over 13 days compared to September's 32 mm (1.2 in) over just 5 days. Additionally, April's humidity is higher at 84%, compared to September's 62%, which contributes to the overall dampness of the month. For more detailed insights, you can check Palouse weather in April.

In comparing the weather of September and May, September typically showcases a broader temperature range, with minimums dipping to 1°C (34°F) and maximums soaring to 35°C (94°F), while the average temperature stands at a comfortable 16°C (61°F). In contrast, May has a slightly lower average temperature of 13°C (56°F), with minimums near freezing at 0°C (32°F) and maximums reaching up to 31°C (89°F). Precipitation is also more prevalent in May, with 68 mm (2.7 in) over 10 days compared to September's 32 mm (1.2 in) over just 5 days. Additionally, May experiences higher humidity levels at 77%, contrasted with September’s 62%. For more details on the weather in May, check out Palouse weather in May.

The weather in September features a wider temperature range, with a minimum of 1°C (34°F) and a maximum of 35°C (94°F), culminating in an average of 16°C (61°F). In contrast, June typically starts off warmer, with minimum temperatures at 4°C (40°F) and reaching up to 42°C (109°F) on hotter days, averaging 18°C (64°F). Both months see a similar level of precipitation, with September receiving 32 mm (1.2 in) and June slightly higher at 33 mm (1.3 in), each experiencing around five days of rain. However, June boasts a higher humidity level at 78%, compared to September's 62%. For more detailed insights, check out Palouse weather in June.

September presents a broader range of temperatures compared to July, with minimums dropping to 1°C (34°F) and maximums reaching up to 35°C (94°F), while July maintains milder temperatures, ranging from a minimum of 8°C (47°F) to a maximum of 40°C (104°F). Although September has a lower overall average temperature of 16°C (61°F), it experiences more precipitation, totaling 32 mm (1.2 in) over 5 days, compared to July's minimal 5 mm (0.2 in) in just 1 day. Additionally, July is characterized by higher humidity at 77%, while September's humidity levels are lower at 62%. For more detailed insights on the weather in July, you can visit Palouse weather in July.

In comparing the weather of September and August, September experiences a wider range of temperatures, with minimums dropping to 1°C (34°F) and maximums reaching up to 35°C (94°F). In contrast, August typically features milder temperatures, with minimums around 6°C (43°F) and maximums peaking at 39°C (103°F). While August is characterized by higher average temperatures of 22°C (72°F), it also sees significantly less precipitation—only 12 mm (0.5 in) over 2 days, compared to September’s 32 mm (1.2 in) over 5 rainy days. Humidity levels are relatively similar, with September at 62% and August slightly higher at 64%. For a more detailed look at August conditions, you can visit Palouse weather in August.

September and October exhibit distinct differences in weather patterns. September boasts a warmer temperature range, with a minimum of 1°C (34°F) and an average of 16°C (61°F), peaking at a high of 35°C (94°F). In contrast, October brings cooler air, with temperatures dropping to a minimum of -15°C (5°F) and an average of 8°C (48°F), while still reaching a maximum of 27°C (81°F). Additionally, October experiences significantly more precipitation, totaling 76 mm (3.0 in) over 11 days compared to September's 32 mm (1.2 in) over just 5 days. The humidity also rises in October to 79%, reflecting the wetter conditions. For a more detailed look into October conditions, visit Palouse weather in October.

September weather is characterized by a wide temperature range, with minimums dropping to 1°C (34°F) and maximums soaring up to 35°C (94°F), resulting in an average temperature of 16°C (61°F). The month experiences relatively low precipitation at 32 mm (1.2 in) over about 5 days, with humidity levels around 62%. In contrast, November brings colder temperatures, with a minimum of -9°C (16°F) and maximums around 17°C (62°F), leading to a significantly lower average of 4°C (39°F). This month also sees more precipitation, totaling 98 mm (3.9 in) across 14 days and higher humidity at 87%. For a deeper insight into November weather patterns, visit Palouse weather in November.

September and December showcase stark contrasts in weather patterns. September enjoys a warm average temperature of 16°C (61°F), with highs reaching up to 35°C (94°F), alongside relatively low precipitation of 32 mm (1.2 in) over just 5 days. In contrast, December brings much colder conditions, with an average temperature plummeting to 0°C (32°F) and a maximum of only 16°C (61°F). Moreover, December experiences significantly higher precipitation of 95 mm (3.8 in) spread across 15 days, contributing to a higher humidity level of 90%. For more details on the December weather, visit Palouse weather in December.

Compare Palouse's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Palouse

As summer transitions to autumn, September weather in Palouse offers a delightful contrast to the sweltering heat of the previous months. Temperatures start to cool down, complemented by increasing humidity levels that introduce a refreshing crispness to the air. With limited precipitation spread across just a handful of days, the month remains largely dry, allowing for vibrant days and cool nights. This unique blend of warmth and chill makes September an ideal time to experience the natural beauty of the region before the full onset of fall. For a comprehensive overview of the seasonal changes, visit Palouse Climate.