Los Altos reaches 100° on about 74 days a year, more than all but 102 U.S. towns
In January the night’s low is typically 46°. Winters are mild: January nights here are milder than in 94% of U.S. towns. Compared with 1901–2000, the average now sits 1.3° higher. The outdoor season runs from November to March, with highs of 68–80°.
A year in Los Altos at a glance
Each month’s typical high and low, and what it brings.
What stands out about Los Altos’ climate
Compared with towns across the U.S., with Los Altos’ place in Texas beside it.
What a year in Los Altos feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 74 days a year reach 100°
And 178 days reach 90°. Frost and day counts come from NOAA’s station at Laredo 2, TX, 9 miles from the town’s center, at about the same height.
The 2023 USDA map puts Los Altos’ center in zone 9b: the coldest night of a typical winter, averaged over 1991–2020, reaches about 29°. 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 20 inches of rain a year
September is the wettest month and February the driest. Rain falls on about 60 days a year. Snow is rare: about 0.1" in a normal year at Laredo 2, TX, so most winters see none.
Rain + melted snow by month
Inches of water
Heating and cooling a home in Los Altos
15% of the work is heating, so air conditioning is the bigger bill. 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 Laredo 2, TX.
Living with Los Altos’ climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
Zone 9b. Frost comes about 9 winters in 10, so the growing year is set by heat, not cold: 74 days at 100° make midsummer the hard season for gardens.
Months with highs of 62–84° and lows of 40° or more: January, February, March, November and December.
Parks & trails →Of the yearly building losses FEMA expects in Los Altos from natural hazards, river flooding is the largest share (49%); heat waves, cold waves, winter storms and ice storms together are 36%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Los Altos and its neighbors
Every town next door is within a degree of Los Altos in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Los Altos’, 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 |
|---|---|---|---|---|
| Los Altos, TX | 46° | 99° | 20" | 0.1" |
| Olivehurst, CA | 39° | 97° | 20" | 0.0" |
| Catalina Foothills, AZ | 39° | 100° | 12" | 0.0" |
| Ivins, UT | 32° | 100° | 11" | 1.2" |
| Summerlin South, NV | 35° | 102° | 5" | 0.2" |
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 Los Altos averaged 1.3° warmer than the 1900s. The biggest change is in February (+2.5°).
A smaller shift than in 56% 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 Los Altos compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Los Altos’ place among Texas’.
Los Altos weather by month
Highs, lows and precipitation from NOAA’s grid at Los Altos’ center; snow, wet days and snow on the ground from Laredo 2, TX. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 68° | 46° | 0.9" | 0.0" | 5 | 0 | 52° – 63° |
| February | 73° | 51° | 0.7" | 0.0" | 5 | 0 | 55° – 70° |
| March | 80° | 57° | 1.3" | 0.0" | 5 | 0 | 63° – 74° |
| April | 87° | 63° | 1.3" | 0.0" | 4 | 0 | 69° – 81° |
| May | 93° | 70° | 2.8" | 0.0" | 5 | 0 | 77° – 85° |
| June | 98° | 75° | 1.8" | 0.0" | 5 | 0 | 83° – 91° |
| July | 99° | 75° | 1.9" | 0.0" | 4 | 0 | 83° – 91° |
| August | 99° | 76° | 1.7" | 0.0" | 5 | 0 | 84° – 92° |
| September | 93° | 72° | 3.9" | 0.0" | 8 | 0 | 79° – 87° |
| October | 86° | 64° | 1.6" | 0.0" | 4 | 0 | 72° – 80° |
| November | 76° | 55° | 1.1" | 0.0" | 4 | 0 | 61° – 71° |
| December | 69° | 48° | 1.1" | 0.1" | 6 | 0 | 51° – 62° |
| Year | 85° | 63° | 20.1" | 0.1" | 60 | 0 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 55° to 70°. June is the most reliable, staying within 7°.
Where Los Altos’ 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 Los Altos’ center.
- Snow: Laredo 2, TX.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Laredo 2, TX, 9 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 Los Altos’ climate
What is the weather like in Los Altos?
A typical July afternoon reaches 99°, a January night drops to 46°, and snow is almost unheard of. Milder January nights than 94% of U.S. towns; hotter July afternoons than all but 156 U.S. towns.
How cold does it get in Los Altos in winter?
January nights average 46°. About 5 nights a year reach 32° or below. In the coldest January of the last 30 years the month averaged 52°.
How much snow does Los Altos get?
About 0.1 inches in a normal winter at Laredo 2, TX, so most winters see none.
How hot does it get in Los Altos?
July, with a typical high of 99° and a low of 75°. About 178 days a year reach 90° and 74 reach 100° (Laredo 2, TX).
When is the first and last frost in Los Altos?
There is no reliable frost date: a 32° night comes in about 90% of winters at Laredo 2, TX, so most years bring a freeze but some pass without one.
What growing zone is Los Altos in?
Zone 9b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 29°.
What is the best time of year to visit Los Altos?
By one simple rule (highs of 62–84° and lows of 40° or more), January, February, March, November and December. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Los Altos getting warmer?
Yes: 1991–2020 averaged 1.3° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 56% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Los Altos.
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.