August weather forecast
Lewiston, ID

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A scenic and dramatic landscape on both sides of the glorious Lewiston City in Idaho, and a clear view of the iconic Snake river passing through
A scenic and dramatic landscape on both sides of the glorious Lewiston City in Idaho, and a clear view of the iconic Snake river passing through

Weather in August

Weather in August remains characterized by high temperatures, nearly mirroring July’s conditions. A slight difference in sunrise and sunset times sees daylight hours decreasing, hinting towards the oncoming fall. Despite being one of the driest months, with a scanty rainfall of 0.31" (8mm), the environment remains adequately hydrated due to water bodies in the region. The relatively stable atmospheric pressure creates comfortable days. It is important to stay wary of the UV index which remains high during this month.

Temperature

The average temperatures reach their apex in August, averaging 85.3°F (29.6°C) at the high end and 59.2°F (15.1°C) at the low end.

Humidity

The least humid month in Lewiston is August, with an average relative humidity of 38%.

Rainfall

The month with the least rainfall is August, when the rain falls for 5.2 days and typically collects 0.31" (8mm) of precipitation.

Snowfall

May through September are months without snowfall.

Daylight

The average length of the day in August is 14h and 7min.
On the first day of August, sunrise is at 5:30 am and sunset at 8:18 pm. On the last day of the month, sunrise is at 6:08 am and sunset at 7:28 pm PDT.

Sunshine

The month with the most sunshine in Lewiston is August, with an average of 12h of sunshine.

UV index

The average daily maximum UV index in August is 5. A UV Index of 3 to 5 symbolizes a medium vulnerability from unprotected exposure to Sun's UV rays for ordinary individuals.
Note: A daily maximum UV index of 5 in August translates into the following instructions:
Take necessary precautions - Defending against sun damage is advocated. The mid-day Sun emits the most powerful UV radiation, so seek shade and minimize exposure. Shield yourself from the harmful effects of UV radiation with sun-protective attire, a hat, and quality sunglasses.
Updated: Jul 26, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What part of the year is the hottest?

August tends to be the warmest month, with temperatures averaging a daily high of 85.3°F (29.6°C) and a low of 59.2°F (15.1°C).

Is it hot during August?

The high-temperature during August is 85.3°F (29.6°C) and the low-temperature is 59.2°F (15.1°C). In July, the average heat index (a.k.a. 'real feel', 'felt air temperature'), which combines air temperature and relative humidity, is calculated to be 84.2°F (29°C).

What is the least humid month?

The least humid month is August, with an average relative humidity of 38%.

What is the average humidity in August in Lewiston?

In Lewiston, the average relative humidity in August is 38%.

What is the driest month?

The month with the least rainfall is August, when the rain falls for 5.2 days and typically collects 0.31" (8mm) of precipitation.

How many days does it rain in August in Lewiston?

In Lewiston, in August, it is raining for 5.2 days, with typically 0.31" (8mm) of accumulated precipitation.

When it does not snow?

May through September are months without snowfall.

How many hours of daylight does Lewiston have in August?

In August, the average day length is 14h and 7min.

What time are sunrise and sunset in August?

In August, on the first day of the month, sunrise is at 5:30 am and sunset at 8:18 pm. On the last day of the month, in Lewiston, sunrise is at 6:08 am and sunset at 7:28 pm PDT.

What month has the most sunshine?

With an average of 12h of sunshine, August has the most sunshine of the year.

How many hours of sunshine does Lewiston have in August?

The average sunshine duration in August is 12h.

What is the UV index reading in August?

In Lewiston, the average daily maximum UV index in August is 5. A UV Index reading of 3 to 5 represents a medium hazard to health from exposure to Sun's UV rays.
Average humidity
Average rainfall days
Average snowfall
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in August
Lewiston, ID

Average temperature in August - Lewiston, ID
  • Average high temperature in August: 85.3°F

The warmest month (with the highest average high temperature) is August (85.3°F).
The month with the lowest average high temperature is December (36.1°F).

  • Average low temperature in August: 59.2°F

The month with the highest average low temperature is August (59.2°F).
The coldest month (with the lowest average low temperature) is December (24.4°F).

Average pressure in August
Lewiston, ID

Average pressure in August - Lewiston, ID
  • Average pressure in August: 29.91"Hg

The month with the highest atmospheric pressure is January (30.2"Hg).
The month with the lowest atmospheric pressure is August (29.91"Hg).

Average wind speed in August
Lewiston, ID

Average wind speed in August - Lewiston, ID
  • Average wind speed in August: 4.3mph

The windiest month (with the highest average wind speed) is April (5.7mph).
The calmest months (with the lowest average wind speed) are July, August and September (4.3mph).

Average humidity in August
Lewiston, ID

Average humidity in August - Lewiston, ID
  • Average humidity in August: 38%

The month with the highest relative humidity is January (84%).
The month with the lowest relative humidity is August (38%).

Average rainfall in August
Lewiston, ID

Average rainfall in August - Lewiston, ID
  • Average rainfall in August: 0.31"

The wettest month (with the highest rainfall) is March (1.85").
The driest month (with the least rainfall) is August (0.31").

Average rainfall days in August
Lewiston, ID

Average rainfall days in August - Lewiston, ID
  • Average rainfall days in August: 5.2 days

The month with the highest number of rainy days is March (17.6 days).
The month with the least rainy days is August (5.2 days).

Average snowfall in August
Lewiston, ID

Average snowfall in August - Lewiston, ID
  • Average snowfall in August: 0"

The month with the highest snowfall is February (3.27").
The months with the least snowfall are May, June, July, August and September (0").

Average snowfall days in August
Lewiston, ID

Average snowfall days in August - Lewiston, ID
  • Average snowfall days in August: 0 days

The month with the highest number of snowfall days is December (8.1 days).
The months with the least snowfall days are May, June, July, August and September (0 days).

Average daylight in August /
Average sunshine in August
Lewiston, ID

Average daylight in August / Average sunshine in August - Lewiston, ID
  • Average daylight in August: 14h and 1min

The month with the longest days is June (Average daylight: 15h and 42min).
The month with the shortest days is December (Average daylight: 8h and 42min).

  • Average sunshine in August: 12h and 0min

The month with the most sunshine is August (Average sunshine: 12h and 0min).
The month with the least sunshine is January (Average sunshine: 5h and 6min).

Average sunshine days in August
Lewiston, ID

Average sunshine days in August - Lewiston, ID
  • Average sunshine days in August: 23.5 days

The month with the most sunshine days is July (24 days).
The months with the least sunshine days are February and March (10.8 days).

Average UV index in August
Lewiston, ID

Average UV index in August - Lewiston, ID
  • Average UV index in August: 5

The month with the highest UV index is July (UV index 7).
The month with the lowest UV index is February (UV index 1).

Average cloud cover in August
Lewiston, ID

Average cloud cover in August - Lewiston, ID
  • Average cloud cover in August: 12

The month with the most cloud cover is February (Cloud cover 48).
The months with the least cloud cover are July and August (Cloud cover 12).

Average visibility in August
Lewiston, ID

Average visibility in August - Lewiston, ID
  • Average visibility in August: 6mi

The months with the highest visibility are March, April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January, February and December (5mi).

Lewiston, Idaho, USA

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