Ketchum Snowfall Totals & Accumulation Averages
This page pulls together information on when, how much and how often Ketchum, Idaho has snow.
There are data and descriptions here of how many days it snows and the total amount of snowfall that Ketchum usually gets. There are also monthly and yearly counts of the days that Ketchum normally has heavy snowstorms and deep snow accumulated on the ground. Plus there's information on when Ketchum can expect the first and last snowfalls of the season.
The numbers are 30-year averages, based mainly on weather data gathered from 1991 to 2020 in Ketchum, near the Sun Valley ski resort. Snow depth data are for 1981 to 2010.
How Often it Snows in Ketchum
This first table lists monthly and yearly totals for amount of snow and how many days it snows at least 0.1 inches (0.25 centimetres).
| Days | Inches | Centimetres | |
|---|---|---|---|
| 8.8 | January | 27.0 | 68.6 |
| 7.6 | February | 17.2 | 43.7 |
| 4.9 | March | 10.5 | 26.7 |
| 2.2 | April | 3.2 | 8.1 |
| 0.2 | May | 0.2 | 0.5 |
| 0.7 | October | 1.6 | 4.1 |
| 3.7 | November | 10.3 | 26.2 |
| 9.9 | December | 32.0 | 81.3 |
| 38.0 | Year | 102.0 | 259.1 |
These averages don't show how much the snowfall in Ketchum varies from year to year.
In December, for instance, one in four years totals over 39.3 inches of snow. Another 25 percent of years receive 19.3 inches or less for the month.
Similarly in January, fresh snowfall in the heaviest years amounts to over 40.2 inches, while the lightest years get under 11.6 inches.
New snow for February ranges from over 28.3 inches in heavy snowfall years to 6.4 inches at most in light years.
When Ketchum Has Its First & Last Snowfalls
The first snowfall of winter for Ketchum usually arrives in November. Every few years, October also gets some snow.
The season's last snowfall most often happens in April. In rare years it doesn't stop snowing until May.
Ketchum is normally free of snow every year from June to September.
How Many Snowstorms Ketchum Gets
Most days of snowfall in Ketchum leave at least an inch of fresh snow. For 15 days a year on average, the amount of new snow totals three inches or more.
Snowstorms of over five inches a day normally occur eight times annually. On a couple of days a year, the storms are major blizzards that dump ten inches or more in one day. Storms this severe can show up anytime from November to March.
| 1 inch 2.5 cm |
3 inches 7.6 cm |
5 inches 12.7 cm |
10 inches 25.4 cm | |
|---|---|---|---|---|
| 6.8 | 3.8 | January | 2.2 | 0.6 |
| 5.9 | 2.9 | February | 1.8 | 0.3 |
| 3.5 | 1.5 | March | 0.6 | 0.1 |
| 1.5 | 0.4 | April | 0.2 | 0.0 |
| 0.1 | 0.0 | May | 0.0 | 0.0 |
| 0.5 | 0.3 | October | 0.1 | 0.0 |
| 3.0 | 1.4 | November | 0.8 | 0.1 |
| 8.3 | 4.2 | December | 2.3 | 0.6 |
| 29.6 | 14.5 | Year | 8.0 | 1.7 |
How Much Snow Normally Accumulates in Ketchum
Throughout winter, Ketchum has at least five inches of snow on the ground.
Indeed, the snowpack usually accumulates to over ten inches from mid December to near the end of March.
| 1 inch 2.5 cm |
3 inches 7.6 cm |
5 inches 12.7 cm |
10 inches 25.4 cm | |
|---|---|---|---|---|
| 31.0 | 31.0 | January | 30.9 | 28.7 |
| 27.8 | 27.7 | February | 27.5 | 27.2 |
| 28.9 | 28.6 | March | 28.1 | 26.8 |
| 11.8 | 11.0 | April | 10.3 | 8.4 |
| 0.2 | 0.0 | May | 0.0 | 0.0 |
| 0.7 | 0.3 | October | 0.3 | 0.0 |
| 13.3 | 11.3 | November | 8.8 | 4.6 |
| 29.6 | 28.0 | December | 27.1 | 21.2 |
| 143.3 | 137.9 | Year | 133.0 | 116.9 |
Reference
NOAA National Centers for Environmental Information (NCEI). Climate Normals.