Photo: Kglavin · CC BY 2.5Kelseyville’s winters are milder and less snowy than most of the U.S.
A typical July afternoon reaches 91°, a January night drops to 37°, and snow is almost unheard of.
A year in Kelseyville at a glance
Each month’s typical high and low, and what it brings.
What stands out about Kelseyville’s climate
Compared with towns across the U.S., with Kelseyville’s place in California beside it.
What a year in Kelseyville feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 209 frost-free days a year
In half of years the last 32° night comes by April 10 and the first by November 6. Frost and day counts come from NOAA’s station at Clearlake 4 Se, CA, 15 miles from the town’s center, at about the same height.
The 2023 USDA map puts Kelseyville’s center in zone 8b: the coldest night of a typical winter, averaged over 1991–2020, reaches about 19°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
About 36 inches of rain a year
January is the wettest month and July the driest. Rain falls on about 79 days a year. Snow is rare: about 0.4" in a normal year at Clearlake 4 Se, CA, so most winters see none.
Rain + melted snow by month
Inches of water
Heating and cooling a home in Kelseyville
82% of the work is heating. Months averaging under 55° run from November through April.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Clearlake 4 Se, CA.
Living with Kelseyville’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
209 frost-free days in zone 8b. The last frost comes by Apr 10 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Nov 6.
Months with highs of 62–84° and lows of 40° or more: April, May, June and October. 3.6 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Kelseyville from natural hazards, river flooding is the largest share (45%). Normals are averages; the hazards page covers the extremes.
Natural hazards →Kelseyville and similar climates
TownRatings has no climate map of the towns around Kelseyville yet.
Climates most like Kelseyville’s, farther away
TownRatings’ own comparison of NOAA 1991–2020 normals, not a NOAA product: places of 5,000+ at least 150 miles away, one per state, closest on January low, July high, precipitation and snow.
| Town | Jan. low | July high | Precip. | Snow |
|---|---|---|---|---|
| Kelseyville, CA | 37° | 91° | 36" | 0.4" |
| Grants Pass, OR | 34° | 90° | 33" | 0.9" |
| Boerne, TX | 39° | 93° | 33" | 0.1" |
| Lugoff, SC | 33° | 92° | 43" | 0.4" |
| Marvin, NC | 31° | 91° | 43" | 0.2" |
Temperatures and precipitation come from NOAA’s 5 km grid; snow and day counts from the stations named on this page.
Warmer than it used to be
The last 30 years in Kelseyville averaged 1.1° warmer than the 1900s. The biggest change is in January (+1.8°).
A smaller shift than in 67% of U.S. towns.
Change by month
The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods.
How Kelseyville compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Kelseyville’s place among California’s.
Kelseyville weather by month
Highs, lows and precipitation from NOAA’s grid at Kelseyville’s center; snow, wet days and snow on the ground from Clearlake 4 Se, CA. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 55° | 37° | 7.5" | 0.2" | 14 | 0 | 41° – 55° |
| February | 57° | 38° | 6.6" | 0.1" | 13 | 0 | 40° – 55° |
| March | 62° | 39° | 5.4" | 0.1" | 10 | 0 | 42° – 58° |
| April | 66° | 42° | 2.5" | 0.0" | 8 | 0 | 47° – 59° |
| May | 75° | 47° | 1.7" | 0.0" | 5 | 0 | 52° – 69° |
| June | 84° | 53° | 0.3" | 0.0" | 2 | 0 | 63° – 74° |
| July | 91° | 58° | 0.0" | 0.0" | 0 | 0 | 71° – 79° |
| August | 90° | 57° | 0.1" | 0.0" | 0 | 0 | 70° – 78° |
| September | 86° | 53° | 0.2" | 0.0" | 1 | 0 | 65° – 73° |
| October | 76° | 47° | 1.6" | 0.0" | 4 | 0 | 56° – 69° |
| November | 62° | 40° | 3.6" | 0.0" | 9 | 0 | 43° – 56° |
| December | 54° | 36° | 7.1" | 0.0" | 13 | 0 | 41° – 50° |
| Year | 71° | 46° | 36.4" | 0.4" | 79 | 0 |
How much a month can swing
A normal is an average. May swings the most: from 1991 to 2020 its average ranged from 52° to 69°. August is the most reliable, staying within 8°.
Where Kelseyville’s numbers come from
Normals are 30-year averages, not a forecast. How TownRatings reads climate data →
- Temperatures and precipitation: NOAA’s gridded 1991–2020 normals for the 5 km cell at Kelseyville’s center.
- Snow: Clearlake 4 Se, CA.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Clearlake 4 Se, CA, 15 miles from the town’s center, at about the same height; the nearest station that passes our checks for distance, height and agreement with the grid.
- Growing zone: USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu/phzm, accessed 8 Oct 2026.
- Then and now: NOAA’s gridded normals for 1901–2000 at the same cell.
- Storms and extremes: FEMA National Risk Index (expected annual losses to buildings).
Common questions about Kelseyville’s climate
What is the weather like in Kelseyville?
A typical July afternoon reaches 91°, a January night drops to 37°, and snow is almost unheard of. Milder January nights than 84% of U.S. towns; hotter July afternoons than 83% of U.S. towns.
How cold does it get in Kelseyville in winter?
December nights average 36°. About 72 nights a year reach 32° or below. In the coldest December of the last 30 years the month averaged 41°.
How much snow does Kelseyville get?
About 0.4 inches in a normal winter at Clearlake 4 Se, CA, so most winters see none.
How hot does it get in Kelseyville?
July, with a typical high of 91° and a low of 58°. About 66 days a year reach 90° and 10 reach 100° (Clearlake 4 Se, CA).
When is the first and last frost in Kelseyville?
In half of years the last spring frost (32°) comes by April 10 and the first fall frost by November 6, about 209 frost-free days, at Clearlake 4 Se, CA.
What growing zone is Kelseyville in?
Zone 8b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 19°.
What is the best time of year to visit Kelseyville?
By one simple rule (highs of 62–84° and lows of 40° or more), April, May, June and October. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Kelseyville getting warmer?
Yes: 1991–2020 averaged 1.1° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 67% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Kelseyville.
Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000; USDA/PRISM 2023 hardiness zones; FEMA National Risk Index. Today’s forecast: National Weather Service.