Julian, California climate: Normal weather by month, frost dates and records
Julian's normal year runs from 38°F December nights to 86°F August afternoons, with 24.5 inches of precipitation and 6 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 14.3°C, December lows of 3°C, August highs of 30°C, 622 mm of precipitation a year.
- NOAA stationJulian Fire Station
- Station IDUSC00044412
- Location33.08°N 116.59°W
- Elevation4,215 ft (1,285 m)
- Population (census place)1,491
On October 14, the normal high in Julian is 71°F and the normal low 50°F, and the chance of measurable rain or snow is 9%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Julian.
- Jan 53° 39°
- Feb 54° 39°
- Mar 58° 41°
- Apr 62° 43°
- May 69° 47°
- Jun 79° 55°
- Jul 86° 63°
- Aug 86° 62°
- Sep 81° 57°
- Oct 71° 50°
- Nov 60° 43°
- Dec 52° 38°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Julian each month?
August is the warmest month, with normal highs of 86°F; December the coldest, with normal lows of 38°F. The most precipitation falls in February (5.34 in), the least in June (0.10 in).
Each month has its own page with the day-by-day normals, the month's records and its recent years:
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 53°F | 39°F | 45.8°F | 4.66 | 1.1 | 6 | <1 | 7 | 10 h 10 min |
| February | 54°F | 39°F | 46.4°F | 5.34 | 1.9 | 8 | <1 | 9 | 11 h |
| March | 58°F | 41°F | 49.2°F | 3.90 | 3.0 | 6 | <1 | 6 | 12 h |
| April | 62°F | 43°F | 52.5°F | 1.94 | 0.2 | 4 | <1 | 3 | 13 h |
| May | 69°F | 47°F | 57.8°F | 0.82 | 0.0 | 3 | <1 | <1 | 13 h 50 min |
| June | 79°F | 55°F | 67.2°F | 0.10 | 0.0 | 1 | 3 | <1 | 14 h 20 min |
| July | 86°F | 63°F | 74.0°F | 0.24 | 0.0 | 1 | 9 | <1 | 14 h 10 min |
| August | 86°F | 62°F | 74.1°F | 0.29 | 0.0 | 1 | 10 | <1 | 13 h 20 min |
| September | 81°F | 57°F | 69.1°F | 0.35 | 0.0 | 1 | 3 | <1 | 12 h 30 min |
| October | 71°F | 50°F | 60.2°F | 1.11 | 0.0 | 3 | 1 | 1 | 11 h 20 min |
| November | 60°F | 43°F | 51.7°F | 2.26 | 0.0 | 4 | <1 | 2 | 10 h 30 min |
| December | 52°F | 38°F | 45.1°F | 3.47 | 0.2 | 6 | <1 | 10 | 10 h |
| Year (annual) | 68°F | 48°F | 57.8°F | 24.48 | 6.4 | 45 | 25 | 37 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 12°C | 4°C | 7.7°C | 118 mm | 3 cm |
| February | 12°C | 4°C | 8.0°C | 136 mm | 5 cm |
| March | 14°C | 5°C | 9.6°C | 99 mm | 8 cm |
| April | 17°C | 6°C | 11.4°C | 49 mm | 1 cm |
| May | 20°C | 8°C | 14.3°C | 21 mm | 0 cm |
| June | 26°C | 13°C | 19.6°C | 3 mm | 0 cm |
| July | 30°C | 17°C | 23.3°C | 6 mm | 0 cm |
| August | 30°C | 17°C | 23.4°C | 7 mm | 0 cm |
| September | 27°C | 14°C | 20.6°C | 9 mm | 0 cm |
| October | 22°C | 10°C | 15.7°C | 28 mm | 0 cm |
| November | 16°C | 6°C | 10.9°C | 57 mm | 0 cm |
| December | 11°C | 3°C | 7.3°C | 88 mm | 1 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00044412; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Julian?
Normal highs sit between 65°F and 85°F in May, June, September and October. Of those, June has the fewest days with rain (1).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00044412.
When is the last frost in Julian?
In Julian, the last spring frost (32°F) comes after March 27 in half of years and after April 30 in one year in ten; the first autumn frost comes before December 1 in half of years and before November 3 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- March 271 year in 10 after April 30; 9 in 10 after February 17
- First autumn frost, half of years before
- December 11 year in 10 before November 3; 9 in 10 before December 21
NOAA puts the median frost-free season at 248 days, and the season without a hard freeze (28°F) at 309 days.
A hard freeze (28°F) comes after February 13 in half of springs and before December 22 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Julian in zone 9a in ZIP code 92066, the nearest ZIP area.
Frost dates for every NOAA station in California · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00044412; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get in Julian?
In a normal year in Julian, 25 days a year reach 90°F, 37 nights fall to 32°F or colder and 45 days bring measurable precipitation.
- Days at 90°F or more
- 25a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 37a normal year
- Days that stay below freezing
- fewer than 1high of 32°F or less
- Days with 0.01 inch of precipitation
- 45a normal year
- Days with 1 inch of snow or more
- 2a normal year
Source: NOAA NCEI 1991-2020 annual normals, station USC00044412.
How sunny is Julian?
Over a year 91% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Julian, 5.8 kWh per square metre a day. June is the sunniest month (96%) and February the cloudiest (84%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 85% | 3.4 |
| February | 84% | 4.3 |
| March | 88% | 5.7 |
| April | 90% | 7.0 |
| May | 93% | 7.9 |
| June | 96% | 8.4 |
| July | 93% | 7.8 |
| August | 94% | 7.3 |
| September | 94% | 6.3 |
| October | 92% | 5.0 |
| November | 89% | 3.7 |
| December | 85% | 3.0 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Julian need?
A normal year in Julian brings 3,528 heating degree days, 34% fewer than the median U.S. place (5,373), and 917 cooling degree days, 1% more than the median (908). Six months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 3,630 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 594 | 0 |
| February | 520 | 0 |
| March | 491 | 1 |
| April | 376 | 2 |
| May | 248 | 25 |
| June | 61 | 126 |
| July | 3 | 282 |
| August | 3 | 286 |
| September | 36 | 160 |
| October | 182 | 33 |
| November | 401 | 2 |
| December | 615 | 0 |
| Year (annual) | 3,528 | 917 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00044412. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Julian been warmer than normal lately?
2025 averaged 59.3°F, 1.5°F above the 1991-2020 normal of 57.8°F. 4 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 59.1°F | +1.3°F | 24.15 | – |
| 2022 | 58.8°F | +1.0°F | 22.78 | – |
| 2023 | 56.2°F | −1.6°F | 44.54 | – |
| 2024 | 58.9°F | +1.1°F | 27.62 | – |
| 2025 | 59.3°F | +1.5°F | 20.30 | – |
Source: observed years: ACIS, station USC00044412. A year counts only with all twelve months complete.
How does Julian's climate compare?
Julian is warmer than 59 of the other 218 places with their own NOAA record in California, and wetter than 154. Across the 7,247 U.S. stations with normals, its annual mean of 57.8°F is warmer than 69%.
In the Köppen classification computed from these normals, Julian is Csa: temperate, dry-summer, hot summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Questions about Julian's climate
What is the coldest month in Julian?
December, with a normal high of 52°F and a normal low of 38°F. The warmest is August (86°F by day, 62°F at night).
Does it snow in Julian?
Yes: 6 inches in a normal year, falling on 2 days with 0.1 inch or more, the most in March (3.0 inches).
What is the rainiest month in Julian?
February, with 5.34 in of precipitation in a normal year; the driest is June with 0.10 in.
What plant hardiness zone is Julian in?
The USDA's 2023 map puts Julian in zone 9a in ZIP code 92066, the nearest ZIP area.
How late can frost come in Julian?
In half of years the last 32°F night comes after March 27; in one year in ten it comes after April 30. Waiting until April 30 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Julian in OctoberThis month day by day, its records and recent years
- California climateThe statewide normals and every place in the state
- Cuyamaca, CA6 miles from this station, 54.0°F a year
- Henshaw Dam, CA15 miles from this station, 57.5°F a year
- Borrego Desert Park, CA17 miles from this station, 73.8°F a year
- Mount Laguna, CA17 miles from this station, 54.4°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made