Photo: Doug Donaldson · CC BY 2.0Hardly any U.S. towns see fresher July days than San Simeon
January nights here settle around 45°. The seasons sit close together: from a winter night to a summer afternoon the average spans only 28°. Winters are mild: January nights here are milder than in 94% of U.S. towns. For walks and days out, the stretch from February to November brings highs of 62–72°.
A year in San Simeon at a glance
Each month’s typical high and low, and what it brings.
What stands out about San Simeon’s climate
Compared with towns across the U.S., with San Simeon’s place in California beside it.
What a year in San Simeon feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
Frost is rare
Frost and day counts come from NOAA’s station at Morro Bay Fire Dept, CA, 24 miles from the town’s center, at about the same height.
The 2023 USDA map puts San Simeon’s center in zone 10a: the coldest night of a typical winter, averaged over 1991–2020, reaches about 34°. 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 21 inches of rain a year
January is the wettest month and July the driest. Rain falls on about 49 days a year. Snow is rare: about 0.0" in a normal year at Hearst Castle, CA, so most winters see none.
Rain + melted snow by month
Inches of water
Heating and cooling a home in San Simeon
91% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from December through March.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Morro Bay Fire Dept, CA.
Living with San Simeon’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
Zone 10a. Frost comes about 1 winter in 7, so tender plants can often stay out through winter.
Months with highs of 62–84° and lows of 40° or more: February, March, April, May, June, July, August, September, October and November. 2.1 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in San Simeon from natural hazards, river flooding is the largest share (40%). Normals are averages; the hazards page covers the extremes.
Natural hazards →San Simeon and similar climates
TownRatings has no climate map of the towns around San Simeon yet.
Climates most like San Simeon’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 |
|---|---|---|---|---|
| San Simeon, CA | 45° | 71° | 21" | 0.0" |
| Port Angeles, WA | 37° | 69° | 28" | 0.4" |
| Makawao, HI | 53° | 75° | 23" | 0.0" |
| Cedar Mill, OR | 36° | 81° | 39" | 3.6" |
| Nantucket, MA | 26° | 76° | 44" | 25" |
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 San Simeon averaged 1.7° warmer than the 1900s. The biggest change is in January (+2.4°).
A bigger shift than in 73% 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 San Simeon compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with San Simeon’s place among California’s.
San Simeon weather by month
Highs, lows and precipitation from NOAA’s grid at San Simeon’s center; snow, wet days and snow on the ground from Hearst Castle, CA. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 62° | 45° | 4.8" | 0.0" | 8 | 0 | 49° – 58° |
| February | 62° | 45° | 4.4" | 0.0" | 9 | 0 | 49° – 58° |
| March | 63° | 45° | 3.6" | 0.0" | 7 | 0 | 48° – 60° |
| April | 64° | 47° | 1.3" | 0.0" | 5 | 0 | 51° – 60° |
| May | 66° | 48° | 0.5" | 0.0" | 2 | 0 | 53° – 63° |
| June | 69° | 50° | 0.1" | 0.0" | 0 | 0 | 55° – 64° |
| July | 71° | 53° | 0.0" | 0.0" | 0 | 0 | 59° – 67° |
| August | 72° | 53° | 0.0" | 0.0" | 0 | 0 | 59° – 66° |
| September | 72° | 53° | 0.1" | 0.0" | 1 | 0 | 59° – 66° |
| October | 70° | 51° | 0.8" | 0.0" | 3 | 0 | 57° – 66° |
| November | 66° | 47° | 1.7" | 0.0" | 5 | 0 | 49° – 60° |
| December | 61° | 44° | 4.1" | 0.0" | 8 | 0 | 49° – 57° |
| Year | 66° | 48° | 21.3" | 0.0" | 49 | 0 |
How much a month can swing
A normal is an average. March swings the most: from 1991 to 2020 its average ranged from 48° to 60°. September is the most reliable, staying within 7°.
Where San Simeon’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 San Simeon’s center.
- Snow: Hearst Castle, CA.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Morro Bay Fire Dept, CA, 24 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 San Simeon’s climate
What is the weather like in San Simeon?
A typical July afternoon reaches 71°, a January night drops to 45°, and snow is almost unheard of. Milder January nights than 94% of U.S. towns; cooler July afternoons than all but 89 U.S. towns.
How cold does it get in San Simeon in winter?
December nights average 44°. About 3 nights a year reach 32° or below. In the coldest December of the last 30 years the month averaged 49°.
How much snow does San Simeon get?
About 0.0 inches in a normal winter at Hearst Castle, CA, so most winters see none.
How hot does it get in San Simeon?
July, with a typical high of 71° and a low of 53°. About 1 days a year reach 90° (Morro Bay Fire Dept, CA).
When is the first and last frost in San Simeon?
Most years have no frost at all: a 32° night comes in about 15% of winters at Morro Bay Fire Dept, CA, usually in December or January.
What growing zone is San Simeon in?
Zone 10a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 34°.
What is the best time of year to visit San Simeon?
By one simple rule (highs of 62–84° and lows of 40° or more), February, March, April, May, June, July, August, September, October and November. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is San Simeon getting warmer?
Yes: 1991–2020 averaged 1.7° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 73% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in San Simeon.
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.