The best times to visit Southwest Idaho for ideal weather are
May 7th to July 8th
July 30th to October 7th
based on average temperature and humidity from NOAA (the National Oceanic and Atmospheric Administration). Read below for more weather and travel details.
Southwest Idaho Travel Guide
Other Southwest Idaho Travel Info
Weather in Southwest Idaho
Average temperatures in Southwest Idaho 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 46th 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 Southwest Idaho, the hottest months are July, August, and then June. See average monthly temperatures below. The warmest time of year is generally mid July where highs are regularly around 97.2°F (36.2°C) with temperatures rarely dropping below 60.7°F (15.9°C) at night.
Southwest Idaho Temperatures (Fahrenheit)
Southwest Idaho 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.
Southwest Idaho Perceived Temperature (F)
Southwest Idaho Perceived Temperature (C)
Average Southwest Idaho 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 Southwest Idaho 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 mid October with an average of 1 days of significant precipitation the week of October 15th.
When can you find snow in Southwest Idaho? Weather stations report a good amount of seasonal snow likely to be deepest around February, especially close to early January. The best time to ski (if at all) in Southwest Idaho is often around around December 3rd 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 Southwest Idaho.
Snow on the Ground
The graph below shows the average snow on the ground in Southwest Idaho (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
Southwest Idaho has some very humid months, with some very dry months. The least humid month is July (18.3% relative humidity), and the most humid month is January (78.9%).
Wind in Southwest Idaho is usually moderate. The windiest month is April, followed by March and May. April’s average wind speed of around 10.1 knots (11.6 MPH or 18.7 KPH) is considered “a gentle 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 21.3 knots, which is considered a fresh breeze.
Relative Humidity (%)
The graph below shows the average % humidity by month in Southwest Idaho.
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||7.6||Gentle breeze||14.4||Significant breeze|
|Feb||8.7||Gentle breeze||16.6||Significant breeze|
|Mar||9.7||Gentle breeze||19.1||Significant breeze|
|Apr||10.1||Gentle breeze||20.4||Strong breeze|
|May||9.6||Gentle breeze||19.2||Significant breeze|
|Jun||8.9||Gentle breeze||18.3||Strong breeze|
|Jul||8.3||Gentle breeze||17.3||Significant breeze|
|Aug||7.8||Gentle breeze||16.7||Significant breeze|
|Sep||7.4||Gentle breeze||15.8||Significant breeze|
|Oct||7.7||Gentle breeze||15.9||Significant breeze|
|Nov||8.1||Gentle breeze||15.9||Significant breeze|
|Dec||8.8||Gentle breeze||16.6||Significant breeze|
Show Relative Humidity by Month
|Month||Avg. Relative Humidity|
Is it Safe to Travel to Southwest Idaho?
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 Southwest Idaho, the United States is July, followed by June and August. 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 Southwest Idaho in December. 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 Southwest Idaho Travel Experience by Season
Spring (March through May)
Humidity and temperatures combine to make this season feel moderately cold. Highs range from 79.1°F (26.2°C) and 49.2°F (9.6°C) with warmer temperatures in the later months. Rain is rare with roughly 2 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 0 to 2 days of precipitation per month. June – August is the busiest season for tourism in Southwest Idaho, so lodging and other accommodations may cost more than usual.
Fall (September through November)
Fall daily highs range from 86.3°F (30.2°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 3 days per month. Tourism is fairly slow during these months due to the weather, so hotels may be lower priced.
Winter (December through February)
Weather is far too cold this time of year in Southwest Idaho to be enjoyable for warm weather travelers. The average high during this season is between 49.2°F (9.6°C) and 35.2°F (1.8°C). On average, it rains or snows a smalll amount: 1 to 2 times per month. These times of year are the slowest with tourists.