Calistoga, California climate: Normal weather by month, frost dates and records
Calistoga's normal year runs from 39°F December nights to 90°F July afternoons, with 38.6 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 15.6°C, December lows of 4°C, July highs of 32°C, 980 mm of precipitation a year.
- NOAA stationCalistoga
- Station IDUSC00041312
- Location38.60°N 122.60°W
- Elevation400 ft (122 m)
- Population5,022
On October 23, the normal high in Calistoga is 76°F and the normal low 46°F, and the chance of measurable rain or snow is 14%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Calistoga.
- Jan 59° 39°
- Feb 62° 41°
- Mar 66° 43°
- Apr 70° 44°
- May 77° 49°
- Jun 85° 53°
- Jul 90° 55°
- Aug 89° 54°
- Sep 87° 52°
- Oct 79° 47°
- Nov 66° 42°
- Dec 58° 39°
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 Calistoga each month?
July is the warmest month, with normal highs of 90°F; December the coldest, with normal lows of 39°F. The most precipitation falls in December (7.95 in), the least in July (0.01 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 59°F | 39°F | 49.1°F | 7.94 | 12 | <1 | 9 | 9 h 40 min |
| February | 62°F | 41°F | 51.4°F | 7.07 | 11 | <1 | 6 | 10 h 40 min |
| March | 66°F | 43°F | 54.2°F | 5.89 | 9 | <1 | 3 | 11 h 50 min |
| April | 70°F | 44°F | 57.3°F | 2.32 | 6 | 1 | 2 | 13 h 10 min |
| May | 77°F | 49°F | 62.5°F | 1.37 | 4 | 4 | <1 | 14 h 10 min |
| June | 85°F | 53°F | 68.6°F | 0.29 | 1 | 11 | <1 | 14 h 50 min |
| July | 90°F | 55°F | 72.1°F | 0.01 | <1 | 18 | <1 | 14 h 40 min |
| August | 89°F | 54°F | 71.7°F | 0.03 | <1 | 17 | <1 | 13 h 40 min |
| September | 87°F | 52°F | 69.8°F | 0.12 | 1 | 14 | <1 | 12 h 30 min |
| October | 79°F | 47°F | 63.0°F | 1.83 | 4 | 6 | <1 | 11 h 20 min |
| November | 66°F | 42°F | 53.8°F | 3.76 | 6 | <1 | 5 | 10 h 10 min |
| December | 58°F | 39°F | 48.1°F | 7.95 | 12 | <1 | 10 | 9 h 30 min |
| Year (annual) | 74°F | 47°F | 60.1°F | 38.58 | 66 | 71 | 36 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 15°C | 4°C | 9.5°C | 202 mm |
| February | 17°C | 5°C | 10.8°C | 180 mm |
| March | 19°C | 6°C | 12.3°C | 150 mm |
| April | 21°C | 7°C | 14.1°C | 59 mm |
| May | 25°C | 9°C | 16.9°C | 35 mm |
| June | 29°C | 12°C | 20.3°C | 7 mm |
| July | 32°C | 13°C | 22.3°C | 0 mm |
| August | 32°C | 12°C | 22.1°C | 1 mm |
| September | 31°C | 11°C | 21.0°C | 3 mm |
| October | 26°C | 9°C | 17.2°C | 46 mm |
| November | 19°C | 5°C | 12.1°C | 96 mm |
| December | 14°C | 4°C | 8.9°C | 202 mm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00041312; 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 Calistoga?
Normal highs sit between 65°F and 85°F in March, April, May, June, October and November. 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 USC00041312.
When is the last frost in Calistoga?
In Calistoga, the last spring frost (32°F) comes after March 2 in half of years and after April 18 in one year in ten; the first autumn frost comes before November 23 in half of years and before November 1 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 21 year in 10 after April 18; 9 in 10 after January 19
- First autumn frost, half of years before
- November 231 year in 10 before November 1; 9 in 10 before December 20
NOAA puts the median frost-free season at 263 days, and the season without a hard freeze (28°F) at 327 days.
A hard freeze (28°F) comes after January 23 in half of springs and before December 6 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Calistoga in zone 9b in ZIP code 94515, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Calistoga's NOAA station is in zone 9a: the coldest night of a typical year reaches 22°F (15 complete years); the map interpolates between stations and terrain, so the station and the ZIP area can differ by half a zone.
Frost dates for every NOAA station in California · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00041312; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. 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 Calistoga?
In a normal year in Calistoga, 71 days a year reach 90°F (13 of them 100°F or more), 36 nights fall to 32°F or colder and 66 days bring measurable precipitation.
- Days at 90°F or more
- 71a normal year
- Days at 100°F or more
- 13a normal year
- Nights at 32°F or colder
- 36a normal year
- Days that stay below freezing
- fewer than 1high of 32°F or less
- Days with 0.01 inch of precipitation
- 66a normal year
Source: NOAA NCEI 1991-2020 annual normals, station USC00041312.
How sunny is Calistoga?
Over a year 87% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Calistoga, 5.1 kWh per square metre a day. July is the sunniest month (95%) and December the cloudiest (72%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 74% | 2.3 |
| February | 77% | 3.3 |
| March | 78% | 4.6 |
| April | 84% | 6.1 |
| May | 88% | 7.3 |
| June | 93% | 8.1 |
| July | 95% | 8.0 |
| August | 94% | 7.1 |
| September | 93% | 5.8 |
| October | 88% | 4.2 |
| November | 81% | 2.8 |
| December | 72% | 2.0 |
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 Calistoga need?
A normal year in Calistoga brings 2,593 heating degree days, 52% fewer than the median U.S. place (5,373), and 836 cooling degree days, 8% fewer than the median (908). Five months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 3,994 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 493 | 0 |
| February | 381 | 0 |
| March | 336 | 3 |
| April | 240 | 9 |
| May | 123 | 45 |
| June | 29 | 137 |
| July | 2 | 222 |
| August | 1 | 209 |
| September | 14 | 158 |
| October | 114 | 52 |
| November | 338 | 2 |
| December | 524 | 0 |
| Year (annual) | 2,593 | 836 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00041312. 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 Calistoga been warmer than normal lately?
2025 averaged 60.3°F, 0.2°F above the 1991-2020 normal of 60.1°F. 2 of the 3 complete years since 2023 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2023 | 59.2°F | −0.9°F | – |
| 2024 | 60.9°F | +0.8°F | – |
| 2025 | 60.3°F | +0.2°F | 33.36 |
Source: observed years: ACIS, station USC00041312. A year counts only with all twelve months complete.
How does Calistoga's climate compare?
Calistoga is warmer than 96 of the other 218 places with their own NOAA record in California, and wetter than 183. Across the 7,247 U.S. stations with normals, its annual mean of 60.1°F is warmer than 75%.
In the Köppen classification computed from these normals, Calistoga 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.
Which places near Calistoga share this climate record?
Middletown has no NOAA station with 1991-2020 normals of its own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Middletown, CA1,659 people · 11 mi N
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Calistoga's climate
What is the coldest month in Calistoga?
December, with a normal high of 58°F and a normal low of 39°F. The warmest is July (90°F by day, 55°F at night).
Does it snow in Calistoga?
Rarely: NOAA's normal is no measurable snow a year.
What is the rainiest month in Calistoga?
December, with 7.95 in of precipitation in a normal year; the driest is July with 0.01 in.
What plant hardiness zone is Calistoga in?
The USDA's 2023 map puts Calistoga in zone 9b in ZIP code 94515, the nearest ZIP area. By the same method at Calistoga's NOAA station, the coldest night of a typical year reaches 22°F (15 years, 1991-2020): zone 9a.
How late can frost come in Calistoga?
In half of years the last 32°F night comes after March 2; in one year in ten it comes after April 18. Waiting until April 18 leaves about a one-in-ten chance of a later frost.
Nearby and next
- California climateThe statewide normals and every place in the state
- Angwin, CA9 miles from this station, 57.4°F a year
- St. Helena, CA9 miles from this station, 61.0°F a year
- Santa Rosa, CA13 miles from this station, 58.1°F a year
- Healdsburg, CA14 miles from this station, 60.2°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made