Longview Weather in September (1981–2025)

📍 46.21°N, 123.07°W •
📊

September at a Glance in Longview

(1981–2025)
Avg High
🔥
21.5°C
Avg Low
❄️
9.2°C
Avg Temp
🌡️
15.4°C
Avg Rain
🌧️
63 mm
Avg Humidity
💧
80%
Avg Wind
🌬️
0.2 m/s
Avg Solar
☀️
4.1
kWh/m²/day
vs Annual
📈
+5.6°C
temp difference
🌤️Mild afternoons❄️Cold mornings🌤️Fairly sunny🌧️Wet month🍃Light winds💦Humid air

Longview September Weather Overview

September is one of the warmer months of the year in Longview, with average highs near 21.5°C and lows around 9.2°C (mean 15.4°C). It is one of the drier months, averaging 63 mm of rainfall and 80% relative humidity across the period.

Longview September Temperature History (1981–2025)

Range

September is one of the warmer months of the year in Longview. Across 45 years of records, the warmest Septembers in Longview were 1990, 2020 and 2022 — when the month averaged 17.1°C — while the coldest was 1983 at 12.8°C. Typical September days reach 21.5°C with nights near 9.2°C. The long-term trend is warming, about 0.3°C per decade.

1981–1985 vs 2021–2025

Avg Temp14.1°C→16.1°C+2°C
Max Temp20.1°C→22.1°C+2°C
Min Temp8.0°C→10.1°C+2.1°C

Trend (per decade)

Avg Temp+0.3°C/decade ↗
Max Temp+0.1°C/decade ↗
Min Temp+0.4°C/decade ↗

Distribution of Avg Temp

12.0°C–13.5°C4 yr (9%)
13.5°C–15.0°C11 yr (24%)
15.0°C–16.5°C20 yr (44%)
16.5°C–18.0°C10 yr (22%)

Longview September Rainfall History (1981–2025)

Range

September is one of the drier months in Longview, averaging 63 mm of rainfall. The wettest September on record was 2013 with 242 mm, while the driest was 1993 at 3 mm.

Longview September Humidity History (1981–2025)

Range

Relative humidity in Longview during September averages 80%. The most humid September was 2010 at 88%, and the least humid was 1989 at 70%.

Longview September Solar History (1981–2025)

Range

September receives about 4.1 kWh/m²/day of solar energy in Longview. The sunniest September was 1998 at 4.9 kWh/m²/day, and the cloudiest were 2013 and 2019 at 3.3.

Longview September Wind History (1981–2025)

Range

Average wind speed in Longview during September is 0.2 m/s. The windiest Septembers were 2021, 2022 and 2023, among others at 0.2 m/s, while the calmest were 2017, 2024 and 2025, among others at 0.1 m/s.

What September Feels Like in Longview

🌅
Cold
Morning
🌞
Mild
Afternoon
🌆
Cool
Evening
Rain chanceModerate
Outdoor comfort★★★★☆

How September Ranks in Longview

🔥3rd warmest month of the year
🌵4th driest month of the year
☀️6th sunniest month of the year

Ranked against the other 11 months using 1981–2025 averages.

Explore Longview Weather by Month

Longview September Averages by Decade

Metric1980s1990s2000s2010s2020sChange
Avg Temp14.6°C15.7°C15.1°C15.5°C16.3°C+1.7°C
Avg High21.0°C22.1°C21.3°C21.3°C22.2°C+1.2°C
Avg Low8.2°C9.3°C8.9°C9.7°C10.2°C+2°C
Avg Rain68 mm53 mm47 mm81 mm68 mm-1 mm

Extreme September Records in Longview

🔥Warmest September37.6°C1988
🧊Coldest September0.3°C2019
🌧️Wettest September242 mm2013
🏜️Driest September3 mm1993
🌬️Windiest September0.2 m/s1981

Key Insights for September

✅

September temperatures in Longview have risen by about 2°C between 1981–1985 and 2021–2025.

✅

September has ranged from a record low of 0.3°C (2019) to a record high of 37.6°C (1988).

✅

Rainfall in September is one of the drier months, averaging 63 mm, with a wettest year of 242 mm.

✅

Daytime highs and overnight lows have shifted differently — highs rose about 0.1°C per decade while lows rose 0.4°C per decade, narrowing the gap between day and night.

Is September a Good Time to Visit Longview?

One of the best times to visit Longview

September is one of the best times to visit Longview. Expect days averaging 21.5°C and nights around 9.2°C (mean 15.4°C) — warmer than Longview's yearly average — with moderate rainfall (63 mm), so conditions are generally comfortable for sightseeing and outdoor plans.

See Longview's complete weather history All 12 months side by side, 1981–2025 records, annual trends and long-term averages in one place. View full history →

Longview Weather in September — In Depth

☀️ September climate overview

September is one of the warmer months of the year in Longview, with average highs near 21.5°C and lows around 9.2°C (mean 15.4°C). It is one of the drier months, averaging 63 mm of rainfall and 80% relative humidity across the period.

🌧️ Rain, humidity & wind in September

September averages 63 mm of rainfall in Longview, one of the drier months compared with the rest of the year. The wettest September on record saw 242 mm (2013), and the driest just 3 mm (1993). Humidity sits around 80% and average wind speed is 0.2 m/s, with solar radiation averaging 4.1 kWh/m²/day.

📈 How September has changed

Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 2°C. Daytime highs moved from 20.1°C to 22.1°C and overnight lows from 8°C to 10.1°C over the same span.
September Weather in Longview, Year by Year
🔥 warmest❄️ coldest🌧️ wettest
YearAvg HighAvg TempAvg LowHottest DayColdest DayRainfallHumidityWindSolar
202521.9°C16.1°C10.3°C29.9°C7.7°C57 mm82%0.1 m/s4
202421.8°C16.0°C10.2°C37.1°C4.3°C38 mm81%0.1 m/s3.8
202321.4°C15.5°C9.7°C30.4°C6.3°C82 mm80%0.2 m/s4
202223.5°C17.1°C10.6°C31.6°C7.9°C14 mm76%0.2 m/s4.2
202121.8°C15.7°C9.5°C30.6°C6.8°C116 mm79%0.2 m/s4.1
202023.0°C17.1°C11.1°C30.2°C8.4°C98 mm78%0.2 m/s3.7
201919.7°C14.9°C10.1°C30.4°C0.3°C135 mm87%0.2 m/s3.3
201820.6°C14.6°C8.7°C29.4°C5.7°C48 mm80%0.2 m/s4.1
201721.9°C16.1°C10.2°C32.2°C5.6°C77 mm80%0.1 m/s3.9
201620.5°C14.8°C9.0°C27.4°C6.6°C56 mm80%0.2 m/s4.2
201520.7°C14.7°C8.7°C33.5°C4.8°C37 mm79%0.1 m/s4
201423.3°C16.9°C10.5°C34.2°C7.7°C63 mm75%0.1 m/s4.2
2013 🌧️20.5°C15.7°C10.9°C34.8°C6.3°C242 mm87%0.1 m/s3.3
201223.0°C15.8°C8.6°C33.5°C6.1°C4 mm76%0.1 m/s4.7
201122.9°C16.5°C10.1°C31.4°C6.1°C52 mm79%0.1 m/s4.2
201019.7°C14.9°C10.0°C26.2°C6.8°C96 mm88%0.1 m/s3.4
200922.1°C15.8°C9.6°C32.6°C4.6°C64 mm77%0.2 m/s4.3
200822.5°C15.6°C8.8°C31.8°C4.8°C11 mm76%0.1 m/s4.4
200720.1°C14.4°C8.7°C31.7°C5.9°C50 mm81%0.2 m/s3.8
200622.4°C15.4°C8.5°C34.5°C6.3°C34 mm77%0.2 m/s4.6
200519.6°C13.8°C8.1°C24.2°C5.5°C48 mm82%0.2 m/s4.2
200419.2°C14.3°C9.4°C25.7°C7.1°C90 mm87%0.1 m/s3.7
200322.9°C16.3°C9.7°C33.2°C6.2°C44 mm78%0.1 m/s4.3
200222.0°C15.4°C8.8°C29.4°C5.1°C34 mm77%0.1 m/s4.4
200121.9°C15.5°C9.1°C27.9°C5.5°C24 mm79%0.1 m/s4.2
200020.3°C14.5°C8.7°C28.8°C1.2°C65 mm80%0.2 m/s4.1
199922.2°C15.1°C8.0°C33.4°C4.0°C8 mm75%0.1 m/s4.8
199822.2°C15.7°C9.2°C27.0°C6.4°C29 mm82%0.1 m/s4.9
199721.0°C15.6°C10.3°C31.5°C6.8°C168 mm85%0.2 m/s4.1
199618.8°C13.3°C7.8°C26.4°C3.5°C87 mm84%0.2 m/s3.6
199522.7°C16.7°C10.7°C29.7°C7.8°C94 mm81%0.1 m/s4
199423.1°C16.6°C10.1°C31.8°C6.6°C48 mm79%0.1 m/s4.3
199323.0°C15.9°C8.9°C32.0°C3.4°C3 mm77%0.2 m/s4.7
199220.5°C14.3°C8.1°C26.4°C4.4°C79 mm78%0.2 m/s4.1
199123.8°C16.7°C9.6°C32.5°C5.9°C5 mm76%0.1 m/s4.7
1990 🔥24.1°C17.1°C10.0°C31.7°C6.4°C12 mm78%0.1 m/s4
198924.0°C16.5°C8.9°C33.3°C6.0°C15 mm70%0.2 m/s4.6
198821.7°C15.0°C8.2°C37.6°C4.7°C60 mm77%0.2 m/s4
198724.3°C16.7°C9.1°C33.4°C5.2°C22 mm73%0.2 m/s4.2
198618.6°C13.2°C7.8°C29.1°C5.4°C118 mm84%0.2 m/s3.5
198519.1°C13.3°C7.4°C24.2°C1.9°C95 mm80%0.2 m/s3.9
198420.0°C14.0°C7.9°C26.2°C2.6°C65 mm78%0.2 m/s3.9
1983 ❄️18.8°C12.8°C6.8°C26.1°C0.7°C51 mm81%0.2 m/s—
198221.1°C15.1°C9.1°C29.8°C4.9°C100 mm81%0.1 m/s—
198121.5°C15.2°C8.9°C36.2°C5.7°C89 mm80%0.2 m/s—

Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.

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Longview September Weather — FAQ

What is the average temperature in Longview in September?▼

The average high in September is around 21.5°C with lows near 9.2°C (mean 15.4°C), based on 45 years of NASA POWER data.

Does it rain a lot in Longview in September?▼

September averages 63 mm of rainfall in Longview, one of the drier months. The wettest on record was 242 mm in 2013.

What was the hottest September on record in Longview?▼

The hottest September reached 37.6°C in 1988. The coldest dipped to 0.3°C in 2019.

Has September in Longview gotten warmer over time?▼

Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 2°C. Daytime highs moved from 20.1°C to 22.1°C and overnight lows from 8°C to 10.1°C over the same span.

Is September a good time to visit Longview?▼

September is one of the warmer months of the year in Longview and one of the drier months, so plan for around 21.5°C daytime highs and 9.2°C at night.

Is September the coldest month in Longview?▼

Not quite — September is the 10th coolest month in Longview, averaging 15.4°C.

What should I pack for Longview in September?▼

For September in Longview, pack light layers you can adjust through the day, with typical highs of 21.5°C and lows of 9.2°C. Bring an umbrella or light rain jacket too.

Is Longview humid in September?▼

Relative humidity in September averages 80% — quite humid.

How windy is Longview in September?▼

Average wind speed in September is 0.2 m/s. The windiest September on record averaged 0.2 m/s (1981).

Which September had the most rainfall in Longview?▼

The wettest September on record was 2013 with 242 mm. On average, September sees 63 mm.

Where does this September weather data come from?▼

All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.

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Explore how the weather in Longview behaves each September, based on 45 years of NASA POWER climate data from 1981 to 2025. This page breaks down average temperatures, rainfall, humidity, wind and solar radiation for September specifically, along with year-by-year records and how the month has changed over the decades.