Photo: Mike Greene · CC BY-SA 2.0Signal Hill has some of the coolest summers among U.S. towns
Midwinter brings lows of about 48°. Temperatures cover 32° across the year, low to high. By precipitation alone, it ranks drier than 96% of U.S. towns. From January to December, highs of 67–80° make it easy to spend the day outdoors.
A year in Signal Hill at a glance
Each month’s typical high and low, and what it brings.
What stands out about Signal Hill’s climate
Compared with towns across the U.S., with Signal Hill’s place in California beside it.
What a year in Signal Hill 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 Long Beach Daugherty Fld, CA, 1.4 miles from the town’s center, at about the same height.
The 2023 USDA map puts Signal Hill’s center in zone 10b: the coldest night of a typical winter, averaged over 1991–2020, reaches about 38°. Plant labels use the zone; frost dates tell you when to plant.
90° days by month
Average days at 90° or more
About 12 inches of rain a year
February is the wettest month and August the driest. Rain falls on about 34 days a year. Snow is rare: about 0.0" in a normal year at Torrance Airport, so most winters see none.
Rain + melted snow by month
Inches of water
Heating and cooling a home in Signal Hill
50% of the work is heating. No month averages under 55°.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Long Beach Daugherty Fld, CA.
Living with Signal Hill’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
Zone 10b. Frost comes about 1 winter in 100, so tender plants can often stay out through winter.
Months with highs of 62–84° and lows of 40° or more: January, February, March, April, May, June, July, August, September, October, November and December. 1.3 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Signal Hill from natural hazards, earthquakes are the largest share (74%). Normals are averages; the hazards page covers the extremes.
Natural hazards →Signal Hill and similar climates
TownRatings has no climate map of the towns around Signal Hill yet.
Climates most like Signal Hill’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 |
|---|---|---|---|---|
| Signal Hill, CA | 48° | 78° | 12" | 0.0" |
| Makawao, HI | 53° | 75° | 23" | 0.0" |
| Sequim, WA | 34° | 71° | 18" | 1.4" |
| Winston, OR | 37° | 86° | 33" | 0.0" |
| Alpine, TX | 30° | 90° | 15" | 2.2" |
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 Signal Hill averaged 2.3° warmer than the 1900s. The biggest change is in January (+3.2°).
A bigger shift than in 98% 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 Signal Hill compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Signal Hill’s place among California’s.
Signal Hill weather by month
Highs, lows and precipitation from NOAA’s grid at Signal Hill’s center; snow, wet days and snow on the ground from Torrance Airport. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 68° | 48° | 3.0" | 0.0" | 6 | 0 | 54° – 63° |
| February | 67° | 49° | 3.3" | 0.0" | 6 | 0 | 54° – 64° |
| March | 68° | 51° | 1.8" | 0.0" | 5 | 0 | 54° – 66° |
| April | 70° | 53° | 0.6" | 0.0" | 2 | 0 | 57° – 66° |
| May | 72° | 57° | 0.2" | 0.0" | 1 | 0 | 60° – 69° |
| June | 74° | 60° | 0.1" | 0.0" | 1 | 0 | 64° – 71° |
| July | 78° | 63° | 0.0" | 0.0" | 1 | 0 | 67° – 75° |
| August | 80° | 64° | 0.0" | 0.0" | 0 | 0 | 69° – 75° |
| September | 80° | 62° | 0.1" | 0.0" | 0 | 0 | 67° – 76° |
| October | 76° | 59° | 0.4" | 0.0" | 2 | 0 | 63° – 74° |
| November | 72° | 52° | 0.8" | 0.0" | 3 | 0 | 56° – 65° |
| December | 67° | 48° | 2.0" | 0.0" | 6 | 0 | 54° – 61° |
| Year | 73° | 55° | 12.2" | 0.0" | 34 | 0 |
How much a month can swing
A normal is an average. March swings the most: from 1991 to 2020 its average ranged from 54° to 66°. August is the most reliable, staying within 6°.
Where Signal Hill’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 Signal Hill’s center.
- Snow: Torrance Airport.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Long Beach Daugherty Fld, CA, 1.4 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 Signal Hill’s climate
What is the weather like in Signal Hill?
A typical July afternoon reaches 78°, a January night drops to 48°, and snow is almost unheard of. Milder January nights than 96% of U.S. towns; cooler July afternoons than 96% of U.S. towns.
How cold does it get in Signal Hill in winter?
December nights average 48°. A night at 32° or below comes in only some winters (0.1 a year on average). In the coldest December of the last 30 years the month averaged 54°.
How much snow does Signal Hill get?
About 0.0 inches in a normal winter at Torrance Airport, so most winters see none.
How hot does it get in Signal Hill?
July, with a typical high of 78° and a low of 63°. About 23 days a year reach 90° and 2 reach 100° (Long Beach Daugherty Fld, CA).
When is the first and last frost in Signal Hill?
Most years have no frost at all: a 32° night comes in about 1% of winters at Long Beach Daugherty Fld, CA, usually in December or January.
What growing zone is Signal Hill in?
Zone 10b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 38°.
What is the best time of year to visit Signal Hill?
By one simple rule (highs of 62–84° and lows of 40° or more), January, February, March, April, May, June, July, August, September, October, November and December. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Signal Hill getting warmer?
Yes: 1991–2020 averaged 2.3° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 98% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Signal Hill.
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.