La Mesa, California Weather
Summer heat deepens across the valleys. Day 15 of summer. Read this microseason across nine climate regions →
La Mesa weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 5Foggy——83°63°—
- MondayJul 6Overcast——83°62°0°
- TuesdayJul 7Overcast——80°61°-3°
- WednesdayJul 8Clear——80°66°0°
- ThursdayJul 9Clear——82°68°+2°
- FridayJul 10Overcast——82°67°0°
- SaturdayJul 11Overcast——79°67°-3°
AQI 51 (Moderate), driven by PM2.5. AQI flat over the last 6 hours (within ±3 points). PM2.5 at 12.0 µg/m³, PM10 at 16.3 µg/m³ — typical background levels with no transport signature.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
What's driving it
PM × Wind × Precip
PM2.5 at 12.0 µg/m³, PM10 at 16.3 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.74
- Wind
- light
- Recent rain
- 0h in last 6h
- Pattern
- background
Trends
Seven days of AQI and PM2.5.
Hourly air-quality data from the Copernicus Atmosphere Monitoring Service, charted across the past and next several days. Dashed lines mark the AQI breakpoints at 50 (Good → Moderate) and 100 (Moderate → Unhealthy for Sensitive Groups).








































If the first of July be rainy weather, 'twill rain more or less for four weeks together.
- Moonrise
- 11:03 PM
- Moonset
- 11:07 AM
- In sign
- ♓︎ Pisces
Summer heat deepens across the valleys
La Mesa at a glance
- Today vs. normal: 77°F — typical for the season
- Last frost: March 4 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
ZIP codes: 91941, 91942
16-Day Forecast — La Mesa
- Sun83°63°0%
- Mon83°62°0%
- Tue80°61°0%
- Wed80°66°0%
- Thu82°68°0%
- Fri82°67°0%
- Sat79°67°1%
- Sun83°69°4%
- Mon82°71°12%
- Tue79°70°12%
- Wed87°73°4%
- Thu95°76°13%
- Fri99°81°19%
- Sat95°80°15%
- Sun88°77°14%
- Mon88°74°13%
Forecast data from Open-Meteo (CC BY 4.0).
Live wind & temperature near La Mesa
Right now in the garden
Peak growing season
As of July 5, the growing season is at its peak — frost is months away. Continue succession-planting beans and summer squash. Start fall brassicas (broccoli, cabbage, kale) from seed indoors for transplanting in late summer.
Microseason · July 1–5
Summer heat deepens across the valleys
Inland temperatures exceed 95°F regularly; fire danger reaches moderate to high across most of the region.
Day 186 of 365 · Wedge 37 of 72
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| January | — | — |
| February | — | — |
| March | lettuce, peas, spinach, radishes | — |
| April | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | — |
| May | tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| June | tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| July | — | tomatoes, beans, summer squash |
| August | — | tomatoes, beans, summer squash |
| September | — | tomatoes, beans, summer squash |
| October | fall brassicas, garlic (overwinter), carrots | winter squash, tomatoes (last) |
| November | fall brassicas, garlic (overwinter), carrots | — |
| December | — | — |
A year in weather
La Mesa peaks at about 74°F in August and bottoms near 55°F in January; February brings the heaviest rain (2.1 inches) and July the least (0.1 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 55° | 2.0″ | 10 |
| February | 56° | 2.1″ | 10 |
| March | 58° | 1.9″ | 12 |
| April | 61° | 1.0″ | 10 |
| May | 64° | 0.3″ | 10 |
| June | 68° | 0.1″ | 8 |
| July | 73° | 0.1″ | 3 |
| August | 74° | 0.1″ | 4 |
| September | 73° | 0.1″ | 5 |
| October | 68° | 0.3″ | 6 |
| November | 61° | 1.0″ | 7 |
| December | 55° | 2.0″ | 9 |
Regional context
La Mesa's climate, from NOAA NCEI 1991-2020 station normals, pairs 55°F Januarys with 73°F Julys — a 18°F swing. About 11 inches of precipitation falls over roughly 94 days a year.
Precipitation in La Mesa peaks in the cool season: February averages 2.1 inches across 9.6 storm-fed days, while July bottoms out at 0.1 inches over just 3.0 rainy days. That cool-season-wet pattern aligns La Mesa with places like Lemon Grove, CA, Casa de Oro-Mount Helix, CA and Spring Valley, CA.
La Mesa rarely sees a hard freeze — its coldest month sits near 55°F — so planting spans most of the calendar. Heat peaks in August around 74°F, which confines cool-season crops to the shoulders of summer. Within La Mesa, low or inland lots lose 3-5°F overnight versus La Mesa's coastal ground.
Similar climates: Lemon Grove, CA, Casa de Oro-Mount Helix, CA, Spring Valley, CA, El Cajon, CA, La Presa, CA.
Frequently asked
- When does it freeze in La Mesa?
- Frost typically leaves La Mesa by mid-March and returns to La Mesa near mid-December.
- What is the rainy season in La Mesa?
- February is the wettest month in La Mesa, about 2.1 inches on average; the year totals roughly 11 inches.
- What is the warmest month in La Mesa?
- La Mesa peaks in August, when the mean runs near 74°F.
- What is the coldest month in La Mesa?
- January is La Mesa's coldest month, averaging about 55°F.
- When can I start a vegetable garden in La Mesa?
- In La Mesa, sow peas and hardy greens around mid-March; La Mesa's tomatoes and peppers wait two weeks more.
- How many rainy days does La Mesa get?
- La Mesa averages about 94 days with measurable rain or snow each year.
- What hardiness zone is La Mesa?
- Since January in La Mesa averages 55°F, La Mesa's USDA zone follows that floor — confirm it by ZIP.
- What is the 10-day forecast for La Mesa?
- La Mesa's extended outlook — daily high and low temperatures and precipitation chances for each upcoming day — is in the daily forecast above.
- Will it rain this week in La Mesa?
- See this week's day-by-day rain chances for La Mesa in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in La Mesa?
- Current conditions for La Mesa and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the La Mesa forecast updated?
- The La Mesa forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in La Mesa?
- Today's sunrise and sunset times for La Mesa are in the Almanac section above, along with civil dawn, civil dusk, and day length. Day length is longest near the summer solstice and shortest near the winter solstice.
- How accurate is the weather forecast for La Mesa?
- The next few days in La Mesa's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
Climate
The hot-summer Mediterranean climate of La Mesa, California carries typical Januarys near 55°F and Julys around 73°F — 18°F of seasonal travel.
Yearly precipitation in La Mesa totals around 11 inches, spread over about 94 days of rain or snow.
La Mesa sits at 32.8°N; that 18°F seasonal swing frames planting windows and frost dates across La Mesa.
ZIP codes in La Mesa
- 91941
- 91942
- 91943
- 91944