The best times to visit Lewiston for ideal weather are
May 7th to July 8th
August 13th to October 21st
based on average temperature and humidity from NOAA (the National Oceanic and Atmospheric Administration). Read below for more weather and travel details.
Lewiston Travel Guide
Other Lewiston Travel Info
Weather in Lewiston
Average temperatures in Lewiston vary drastically. Considering humidity, temperatures feel cold for about half of the year and otherwise nice with a very low chance of rain or snow throughout the year. The area is somewhat temperate — in the 41st percentile for pleasant weather — compared to tourist destinations worldwide. Weeks with ideal weather are listed above. If you’re looking for the very warmest time to visit Lewiston, the hottest months are July, August, and then June. See average monthly temperatures below. The warmest time of year is generally early August where highs are regularly around 96.8°F (36°C) with temperatures rarely dropping below 61.6°F (16.4°C) at night.
Lewiston Temperatures (Fahrenheit)
Lewiston Temperatures (Celsius)
The way we experience weather isn’t all about temperature. Higher temperatures affect us much more at higher humidity, and colder temperatures feel piercing with high winds. Our perceived temperatures factor in humidity and wind chill to better represent how hot or cold the day feels to a person.
Lewiston Perceived Temperature (F)
Lewiston Perceived Temperature (C)
Average Lewiston Temperatures by Month
Daily highs (averaged for the month) usually give the best indication of the weather. A significantly lower mean and low generally just means it gets colder at night.
|Month||Avg. High (°F)||Avg. Mean (°F)||Avg. Low (°F)|
|Month||Avg. High (°C)||Avg. Mean (°C)||Avg. Low (°C)|
Precipitation (Rain or Snow)
If dry weather is what you’re after, the months with the lowest chance of significant precipitation in Lewiston are July, August, and then September. Note that we define “significant precipitation” as .1 inches or more in this section. The lowest chance of rain or snow occurs around early July. For example, on the week of July 2nd there are no days of precipitation on average. By contrast, it’s most likely to rain or snow in late March with an average of 2 days of significant precipitation the week of March 26th.
When can you find snow in Lewiston? Weather stations report a good amount of seasonal snow likely to be deepest around February, especially close to early February. The best time to ski (if at all) in Lewiston is often around around December 17th when fresh powder is deepest. Please note that a value of 0 for snow in the graph below may either mean there was no snow, or that snow is unreported.
Chance of Precipitation
The graph below shows the % chance of rainy and snowy days in Lewiston.
Snow on the Ground
The graph below shows the average snow on the ground in Lewiston (in).
Average Rain and Snow by Month
|Month||Daily Chance of Rain||Average Snow Depth (in)||Total Precipitation (in)|
|Month||Daily Chance of Rain||Average Snow Depth (cm)||Total Precipitation (cm)|
Humidity and Wind
Lewiston has some humid months, and dry months in the opposite season. The least humid month is July (23.9% relative humidity), and the most humid month is December (65.7%).
Wind in Lewiston is usually calm. The windiest month is April, followed by January and March. April’s average wind speed of around 5.3 knots (6.1 MPH or 9.8 KPH) is considered “a light breeze.” Maximum sustained winds (the highest speed for the day lasting more than a few moments) are at their highest in early to mid April where average top sustained speeds reach 14.8 knots, which is considered a moderate breeze.
Relative Humidity (%)
The graph below shows the average % humidity by month in Lewiston.
The graph below shows wind speed (max and average) in knots.
Average Wind Speeds
Show Wind Speeds
All wind speeds are in knots. 1 knot = 1.15 MPH or 1.85 KPH.
|Month||Avg. Wind||Avg. Wind Feel||Sustained High Wind||High Wind Feel|
|Jan||5.1||Light breeze||12.2||Significant breeze|
|Feb||4.5||Light breeze||11.3||Significant breeze|
|Mar||4.9||Light breeze||13||Significant breeze|
|Apr||5.3||Light breeze||13.5||Significant breeze|
|May||4.6||Light breeze||11.9||Significant breeze|
|Jun||4.5||Light breeze||12.2||Significant breeze|
|Jul||4.4||Light breeze||12.3||Significant breeze|
|Aug||4.1||Light breeze||12||Significant breeze|
|Sep||3.8||Barely noticeable||10.6||Significant breeze|
|Oct||3.8||Barely noticeable||10.3||Gentle breeze|
|Nov||4.5||Light breeze||11.5||Significant breeze|
|Dec||4.6||Light breeze||11.8||Significant breeze|
Show Relative Humidity by Month
|Month||Avg. Relative Humidity|
Is it Safe to Travel to Lewiston?
Our best data indicates this area is generally safe. As of Oct 07, 2019 there are no travel advisories or warnings for the United States; exercise normal security precautions. Check this page for any recent changes or regions to avoid: Travel Advice and Advisories. This advisory was last updated on Sep 23, 2019.
The Busiest and Least Crowded Months
The busiest month for tourism in Lewiston, ID, US is July, followed by August and May. Prices for hotels and flights will be most expensive during these months, though you can save if you purchase well in advance. Tourists are unlikely to visit Lewiston in September. Those willing to visit at these times will likely find it the least expensive month.
Estimated Tourism by Month
Most Popular Months to Visit
Overall Lewiston Travel Experience by Season
Spring (March through May)
Humidity and temperatures combine to make this season feel moderately cold. Highs range from 78.9°F (26.1°C) and 51.2°F (10.7°C) with warmer temperatures in the later months. Rain is somewhat common with 4 to 5 days of significant precipitation per month. Spring is the second busiest for tourism, which makes it a good time for those looking for things to do.
Summer (June through August)
The middle-year months have very comfortable weather with high temperatures that are quite warm. These months see the least precipitation with 1 to 4 days of precipitation per month. June – August is the busiest season for tourism in Lewiston, so lodging and other accommodations may cost more than usual.
Fall (September through November)
Fall daily highs range from 87.7°F (30.9°C) and 44.3°F (6.8°C), which will feel chilly given the humidity and wind. It rains or snows a normal amount: 1 to 4 days per month. Tourism is the slowest during these months due to the weather, so hotels may be affordably priced.
Winter (December through February)
Weather is too cold this time of year in Lewiston to be enjoyable for warm weather travelers. The average high during this season is between 53°F (11.7°C) and 42°F (5.6°C). On average, it rains or snows a smalll amount: 3 to 4 times per month. These times of year are fairly slow with tourists.