Lewis and Clark County (Helena)
August
Weather in Lewis and Clark County, Montana for August 2026
Your guide to Lewis and Clark County weather in August - trends and predictions
So far, August 2026 in Lewis and Clark County shows a warmer trend than usual by 2.3 °F.
The forecast for the upcoming days in Lewis and Clark County predicts a temperature of 28.6 °F, which is slightly above the historical average.
In general, the average temperature in Lewis and Clark County at the beginning of August is 27.3 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 24.1 °F by the end of August.
With an average of 4 rainy days, Lewis and Clark County experiences minimal rainfall in August.
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Temperatures
Rain 🌧️
More
27
Dry days
4
Rainy days
0
Snow days
26°/11°
Temperatures
18 km/h
Avg max wind
49 %
Avg humidity
Lewis and Clark County Weather August
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Temperatures trend during August in Lewis and Clark County
See the weather trend as well as the moving average line
August weather in Lewis and Clark County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Aug. 1 |  Thundery outbreaks possible | 33° /14° | 0 mm | 9 | |
| Aug. 2 |  Overcast | 26° /14° | 0 mm | 8 | |
| Aug. 3 |  Sunny | 24° /11° | 0.2 mm | 9 | |
| Aug. 4 |  Heavy rain at times | 23° /8° | 5.2 mm | 8 | |
| Aug. 5 |  Cloudy | 27° /8° | 2.5 mm | 8 | |
| Aug. 6 |  Partly cloudy | 30° /11° | 0 mm | 9 | |
| Aug. 7 | Thundery outbreaks possible | 28° /12° | 0 mm | 8 | |
| Aug. 8 | Overcast | 25° /10° | 0 mm | 7 | |
| Aug. 9 | Sunny | 33° /15° | 0 mm | 6.4 | |
| Aug. 10 | Sunny | 33° /11° | 0 mm | 5.7 | |
| Aug. 11 | Sunny | 33° /12° | 0 mm | 6.4 | |
| Aug. 12 | Sunny | 27° /10° | 0 mm | 6.6 | |
| Aug. 13 | Sunny | 23° /9° | 0 mm | 6 | |
| Aug. 14 | Cloudy | 19° /8° | 0 mm | 5 | |
| Aug. 15 | Sunny | 26° /5° | 3.7 mm | 7 | |
| Aug. 16 | Sunny | 30° /10° | 0 mm | 8 | |
| Aug. 17 | Sunny | 31° /13° | 0.3 mm | 8 | |
| Aug. 18 | Sunny | 30° /11° | 0 mm | 8 | |
| Aug. 19 | Sunny | 29° /13° | 0 mm | 7 | |
| Aug. 20 |  Patchy rain possible | 27° /13° | 0.6 mm | 7 | |
| Aug. 21 | Sunny | 28° /11° | 0.6 mm | 7 | |
| Aug. 22 | Sunny | 31° /13° | 0 mm | 8 | |
| Aug. 23 | Sunny | 26° /8° | 0 mm | 7 | |
| Aug. 24 | Partly cloudy | 26° /9° | 0 mm | 7 | |
| Aug. 25 | Sunny | 27° /12° | 0 mm | 7 | |
| Aug. 26 | Cloudy | 29° /14° | 0 mm | 6 | |
| Aug. 27 | Overcast | 23° /12° | 1.3 mm | 5 | |
| Aug. 28 | Heavy rain at times | 14° /11° | 20.4 mm | 3 | |
| Aug. 29 | Sunny | 23° /10° | 0 mm | 6 | |
| Aug. 30 | Sunny | 26° /10° | 0 mm | 7 | |
| Aug. 31 | Sunny | 27° /11° | 0 mm | 7 | |
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Important Notice
Our weather forecast for Lewis and Clark County in August is based on the analysis of historical data rather than real-time forecast models. While this provides a general overview, weather conditions can change. We recommend that you check the Lewis and Clark County forecast closer to your planned date for the most up-to-date weather information.
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Lewis and Clark County in August - FAQ
What are the expected maximum and minimum temperatures in Lewis and Clark County during August?
Enjoy moderate daytime temperatures of up to 26° and cooler nights around 11°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Lewis and Clark County during August?
In August, Lewis and Clark County can expect light to moderate rainfall, totaling 37.3 mm across approximately 4 days. Occasional showers are possible, and planning ahead for them could be helpful.
What are the typical wind conditions in Lewis and Clark County during August?
The average wind speed in Lewis and Clark County during August is 18 km/h, suggesting breezy to windy conditions, depending on your activities.
August rainfall patterns in Lewis and Clark County
Explore the daily rainfall trends and prepare for Lewis and Clark Countys August weather 💧
Typically, Lewis and Clark County has 4 rainy days in August with a total of 37.3 mm of rainfall.
UV exposure in Lewis and Clark County during August
Stay informed about UV levels for safe outdoor activities throughout the month of August ☀️
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Where is Lewis and Clark County?Get accurate weather forecasts for Lewis and Clark County, located at latitude 46.593 and longitude -112.036. Stay updated with localized weather information tailored for Lewis and Clark County.
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