San Ysidro has chilly winters and hot summers, with very little rain
A typical July afternoon reaches 96°, a January night drops to 27°, and about 1 inches of snow falls in a normal winter.
A year in San Ysidro at a glance
Each month’s typical high and low, and what it brings.
What stands out about San Ysidro’s climate
Read from where San Ysidro sits among New Mexico’s towns. The page puts what stands out first.
Living with San Ysidro’s climate
What the numbers mean for a garden, a driveway, a furnace and a free afternoon.
241 frost-free days. The last frost comes by Mar 12 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 13.
About 1" in a normal winter.
Months averaging under 55° run from November through March. Heating is 57% of the year’s heating-and-cooling load.
About 109 days a year reach 90°, and July afternoons average 96°.
The nicest months are April and October.
Parks & trails →Normals are averages. Ice storms, nor’easters, floods and heat waves are on the natural hazards page.
Natural hazards →About 241 frost-free days a year
In half of years the last 32° night comes by March 12 and the first by November 13.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
What a year in San Ysidro feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
1 inches of snow, 9 of rain and melt
July is the wettest month and April the driest. Rain or snow falls on about 47 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
About 1.0" in a normal year, so most winters see none.
Warmer than it used to be
The last 30 years in San Ysidro averaged 1.8° warmer than the 1900s. The biggest change is in March (+2.5°).
A bigger shift than in 89% of U.S. towns.
Change by month
How San Ysidro compares
Against every U.S. town on TownTapestry, each counted once, with its place in New Mexico.
San Ysidro weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 58° | 27° | 0.5" | 0.4" | 3 | 0 | 38° – 47° |
| February | 64° | 32° | 0.4" | 0.1" | 3 | 0 | 43° – 53° |
| March | 71° | 37° | 0.2" | 0 | 2 | 0 | 50° – 60° |
| April | 79° | 44° | 0.2" | 0 | 2 | 0 | 56° – 66° |
| May | 88° | 53° | 0.4" | 0 | 2 | 0 | 67° – 75° |
| June | 97° | 63° | 0.6" | 0 | 3 | 0 | 75° – 83° |
| July | 96° | 68° | 2.1" | 0 | 9 | 0 | 78° – 85° |
| August | 94° | 66° | 1.7" | 0 | 8 | 0 | 77° – 84° |
| September | 89° | 60° | 1.3" | 0 | 5 | 0 | 69° – 78° |
| October | 80° | 47° | 0.9" | 0.1" | 4 | 0 | 61° – 68° |
| November | 68° | 35° | 0.5" | 0 | 3 | 0 | 45° – 58° |
| December | 58° | 28° | 0.7" | 0.4" | 3 | 0 | 38° – 47° |
| Year | 78° | 47° | 9.3" | 1.0" | 47 | 1 |
Heating and cooling a home in San Ysidro
57% of the work is heating.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. Source: NOAA station normals.
How much a month can swing
A normal is an average. November swings the most: from 1991 to 2020 its average ranged from 45° to 58°. October is the most reliable, staying within 7°.
Common questions about San Ysidro’s climate
What is the coldest month in San Ysidro?
January, with a typical high of 58° and a low of 27°.
What is the hottest month in San Ysidro?
June, with a typical high of 97° and a low of 63°. About 109 days a year reach 90°.
How much snow does San Ysidro get?
About 1 inches in a normal winter, most of it in January.
When is the first frost in San Ysidro?
In half of years the first 32° night comes by November 13, and the last spring frost by March 12.
What is the rainiest month in San Ysidro?
July, with 2.1 inches of rain and melted snow. The year totals 9 inches.
Neighbors talk weather
Gardens, snow, and the best days of the year in San Ysidro.
Your answer becomes a post in Town Square.
Temperatures and rainfall come from NOAA’s gridded climate normals for San Ysidro itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at State Univ, NM (6 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000. Today’s forecast: National Weather Service.