Photo: Thankstelfair · Public domainWinchester reaches 100° on about 39 days a year, more than 98% of U.S. towns
A typical July afternoon reaches 96°, a January night drops to 40°, and snow is almost unheard of.
A year in Winchester at a glance
Each month’s typical high and low, and what it brings.
What stands out about Winchester’s climate
Compared with towns across the U.S., with Winchester’s place in California beside it.
What a year in Winchester feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 315 frost-free days a year
In half of years the last 32° night comes by January 31 and the first by December 10. Frost and day counts come from NOAA’s station at San Jacinto, CA, 8 miles from the town’s center, at about the same height.
The 2023 USDA map puts Winchester’s center in zone 9b: the coldest night of a typical winter, averaged over 1991–2020, reaches about 26°. 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 13 inches of rain a year
February is the wettest month and June the driest. Rain falls on about 35 days a year. Snow is rare: about 0.0" in a normal year at San Jacinto, CA, so most winters see none.
Rain + melted snow by month
Inches of water
Heating and cooling a home in Winchester
50% of the work is heating, so air conditioning is the bigger bill. Months averaging under 55° run from December through February.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at San Jacinto, CA.
Living with Winchester’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
315 frost-free days in zone 9b. The last frost comes by Jan 31 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Dec 10.
Months with highs of 62–84° and lows of 40° or more: February, March, April, May, October and November. 11 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Winchester from natural hazards, river flooding is the largest share (67%); heat waves, cold waves, winter storms and ice storms together are 1%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Winchester and its neighbors
Hemet has the coldest January nights next door (38°, 2° colder) and Hemet the hottest July afternoons (97°, 1° warmer). Differences under a degree are within what the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Winchester’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 |
|---|---|---|---|---|
| Winchester, CA | 40° | 96° | 13" | 0.0" |
| Corona de Tucson, AZ | 36° | 96° | 14" | 0.1" |
| Fort Stockton, TX | 33° | 96° | 13" | 1.4" |
| Anthony, NM | 31° | 96° | 9" | 0.0" |
| Ivins, UT | 32° | 100° | 11" | 1.2" |
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value. Snow and frost-free days come from the nearest weather station, so neighbors often share them.
Warmer than it used to be
The last 30 years in Winchester averaged 2.2° warmer than the 1900s. The biggest change is in January (+3.3°).
A bigger shift than in 95% 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 Winchester compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Winchester’s place among California’s.
Winchester weather by month
Highs, lows and precipitation from NOAA’s grid at Winchester’s center; snow, wet days and snow on the ground from San Jacinto, CA. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 67° | 40° | 2.7" | 0.0" | 6 | 0 | 49° – 60° |
| February | 67° | 41° | 3.3" | 0.0" | 6 | 0 | 49° – 62° |
| March | 71° | 44° | 1.9" | 0.0" | 5 | 0 | 51° – 64° |
| April | 75° | 46° | 0.8" | 0.0" | 3 | 0 | 55° – 64° |
| May | 81° | 51° | 0.3" | 0.0" | 2 | 0 | 59° – 71° |
| June | 89° | 56° | 0.0" | 0.0" | 0 | 0 | 67° – 77° |
| July | 96° | 61° | 0.1" | 0.0" | 1 | 0 | 72° – 85° |
| August | 97° | 62° | 0.1" | 0.0" | 1 | 0 | 76° – 84° |
| September | 92° | 59° | 0.2" | 0.0" | 1 | 0 | 72° – 81° |
| October | 83° | 51° | 0.5" | 0.0" | 2 | 0 | 63° – 72° |
| November | 74° | 44° | 1.0" | 0.0" | 3 | 0 | 51° – 64° |
| December | 66° | 39° | 1.8" | 0.0" | 5 | 0 | 47° – 60° |
| Year | 80° | 49° | 12.6" | 0.0" | 35 | 0 |
How much a month can swing
A normal is an average. March swings the most: from 1991 to 2020 its average ranged from 51° to 64°. August is the most reliable, staying within 7°.
Where Winchester’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 Winchester’s center.
- Snow: San Jacinto, CA.
- Frost, freezing nights, 90° and 100° days, heating and cooling: San Jacinto, CA, 8 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 Winchester’s climate
What is the weather like in Winchester?
A typical July afternoon reaches 96°, a January night drops to 40°, and snow is almost unheard of. Milder January nights than 89% of U.S. towns; hotter July afternoons than 96% of U.S. towns.
How cold does it get in Winchester in winter?
December nights average 39°. About 15 nights a year reach 32° or below. In the coldest December of the last 30 years the month averaged 47°.
How much snow does Winchester get?
About 0.0 inches in a normal winter at San Jacinto, CA, so most winters see none.
How hot does it get in Winchester?
July, with a typical high of 96° and a low of 61°. About 120 days a year reach 90° and 39 reach 100° (San Jacinto, CA).
When is the first and last frost in Winchester?
In half of years the last spring frost (32°) comes by January 31 and the first fall frost by December 10, about 315 frost-free days, at San Jacinto, CA.
What growing zone is Winchester in?
Zone 9b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 26°.
What is the best time of year to visit Winchester?
By one simple rule (highs of 62–84° and lows of 40° or more), February, March, April, May, October and November. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Winchester getting warmer?
Yes: 1991–2020 averaged 2.2° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 95% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Winchester.
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.