Highgrove, California Weather
Summer heat deepens across the valleys. Day 15 of summer. Read this microseason across nine climate regions →
Highgrove weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 5Overcast——92°65°—
- MondayJul 6Clear——93°61°+1°
- TuesdayJul 7Clear——96°65°+3°
- WednesdayJul 8Clear——100°75°+4°
- ThursdayJul 9Clear——101°77°+1°
- FridayJul 10Clear——98°76°-3°
- SaturdayJul 11Overcast——97°75°-1°
AQI 36 (Good), driven by PM2.5. AQI flat over the last 6 hours (within ±3 points). PM2.5 at 10.1 µg/m³, PM10 at 13.2 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
Ozone × UV × Sky
Ozone at AQI 30 now. With UV 8.6 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 34 around 1 PM.
- Present
- AQI 30
- UV peak
- 8.6 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 34
PM × Wind × Precip
PM2.5 at 10.1 µg/m³, PM10 at 13.2 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.77
- 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
- 11:05 PM
- Moonset
- 11:08 AM
- In sign
- ♓︎ Pisces
Summer heat deepens across the valleys
Highgrove at a glance
- Today vs. normal: 79°F — typical for the season
- Last frost: March 11 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
16-Day Forecast — Highgrove
- Sun92°65°1%
- Mon93°61°1%
- Tue96°65°0%
- Wed100°75°0%
- Thu101°77°0%
- Fri98°76°0%
- Sat97°75°1%
- Sun97°75°1%
- Mon98°76°8%
- Tue98°79°14%
- Wed102°80°7%
- Thu102°82°13%
- Fri110°85°14%
- Sat116°91°12%
- Sun102°86°19%
- Mon99°81°18%
Forecast data from Open-Meteo (CC BY 4.0).
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
Highgrove's warmest month is August (~80°F mean) and its coldest is December (~50°F). Rainfall peaks in February (2.7 inches) and bottoms out in June (0.0 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 50° | 2.5″ | 11 |
| February | 52° | 2.7″ | 10 |
| March | 54° | 2.5″ | 13 |
| April | 60° | 1.2″ | 9 |
| May | 67° | 0.4″ | 6 |
| June | 73° | 0.0″ | 2 |
| July | 79° | 0.4″ | 3 |
| August | 80° | 0.3″ | 3 |
| September | 76° | 0.3″ | 3 |
| October | 68° | 0.5″ | 5 |
| November | 57° | 1.2″ | 7 |
| December | 50° | 2.2″ | 10 |
Regional context
Drawing on NOAA NCEI 1991-2020 normals, Highgrove's January averages 50°F and July 79°F — 29°F apart — while precipitation totals roughly 14.3 inches over some 81 days.
Highgrove's moisture rides winter storm tracks: February brings 2.7 inches over 10.2 wet days, while June sees only 0.0 inches across 1.8 days in the dry warm season. That cool-season-wet pattern aligns Highgrove with places like Grand Terrace, CA, Colton, CA and Loma Linda, CA.
Highgrove rarely sees a hard freeze — its coldest month sits near 50°F — so planting spans most of the calendar. Heat peaks in August around 80°F, which confines cool-season crops to the shoulders of summer. Highgrove's coastal lots stay 4-7°F milder overnight than Highgrove's inland parcels.
Similar climates: Grand Terrace, CA, Colton, CA, Loma Linda, CA, Bloomington, CA, Riverside, CA.
Frequently asked
- When does it freeze in Highgrove?
- In Highgrove, expect the last spring frost near mid-March; Highgrove's first autumn frost comes around mid-December.
- What is the rainy season in Highgrove?
- February is the wettest month in Highgrove, about 2.7 inches on average; the year totals roughly 14 inches.
- What is the warmest month in Highgrove?
- Highgrove peaks in August, when the mean runs near 80°F.
- What is the coldest month in Highgrove?
- December is Highgrove's coldest month, averaging about 50°F.
- When can I start a vegetable garden in Highgrove?
- Around mid-March, start frost-hardy crops in Highgrove; tomatoes and basil belong a fortnight later.
- How many rainy days does Highgrove get?
- Expect roughly 81 wet days a year in Highgrove.
- What hardiness zone is Highgrove?
- With December around 50°F, Highgrove's zone reflects that minimum — the USDA ZIP map confirms Highgrove's band.
- What is the 10-day forecast for Highgrove?
- Highgrove'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 Highgrove?
- See this week's day-by-day rain chances for Highgrove in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in Highgrove?
- Current conditions for Highgrove and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the Highgrove forecast updated?
- The Highgrove forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in Highgrove?
- Today's sunrise and sunset times for Highgrove 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 Highgrove?
- The next few days in Highgrove's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
Climate
Set in a hot-summer Mediterranean zone, Highgrove, California swings from 50°F in the heart of winter to 79°F at midsummer — a 29°F arc.
Yearly precipitation in Highgrove totals around 14 inches, spread over about 81 days of rain or snow.
Highgrove's 29°F range, set by its 34.0°N position, drives frost timing and what thrives in Highgrove.
ZIP codes in Highgrove
- 92507