Twitchell Dam, CA Climate: Temperature & Rain by Month
Annual temperature and rainfall from NOAA NCEI's 1991–2020 normals →; comfort score computed by PlainClimate
30-year climate normals (1991-2020) from Twitchell Dam's primary NOAA station, TWITCHELL DAM.
The climate verdict for Twitchell Dam
Dryness leads the climate profile for Twitchell Dam, California, with 18.2 inches of precipitation a year. NOAA records an annual average of 58°F. It scores 80/100 for climate comfort (excellent), putting it in the top third of station-mapped location scores and exceeding 76% of them.
- 58°F
- annual average temperature (NOAA normal)
- 80/100
- comfort score, above 76% of station-mapped location scores
- 18.2"
- annual precipitation
- 303 days
- growing season, frost-free days
Twitchell Dam: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00049111 · Twitchell Dam, CA 58°F mean · 18.2" precip
TEMP-MILD · RANK-UPPER · PHOTO-FINISH · PRCP-DRY · SWING-NARROW · COMF-TOP · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-MILD 58°F
- RANK-UPPER #4,803
- PHOTO-FINISH ≈ Carmel Valley
- PRCP-DRY 18.2"
- SWING-NARROW 15°F
- COMF-TOP 80/100
- LOAD-HEAT 2,706 HDD
- STN-1 USC00049111
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Carmel Valley, CA ( -0.1 °F mean)
Instrument codes from this station's NOAA 1991–2020 normals, mean temperature, corpus warmth rank, photo-finish peer station, precipitation band, seasonal swing, comfort composite, degree-day load, and field book, not a livability rating.
Mean-temperature neighbourhood
Nationwide NOAA normal poles and nearest peers, not a reprint of every CA station list.
- Hot Hollister, CA 59°F
- Near Palo Alto, CA 59°F
- Twitchell Dam (this station) 58°F
- Cold Petaluma, CA 58°F
- Near Carmel Valley, CA 58°F
Climate Living Index · Twitchell Dam
Twitchell Dam: 80/100 · grade B
Twitchell Dam publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Twitchell Dam, not an official NOAA rating. Rankings still use Comfort Score 80/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Frost-free season | 303 days/year | 100/100 · A |
| Normal heat + freeze calendar | 0 calendar days | 100/100 · A |
| Snowfall burden | 0.0 inches/year | 90/100 · A |
| Annual temperature balance | 58.4°F · 9.1° from 67.5°F | 71/100 · B |
| Precipitation balance | 18.2 in · 16.8 from 35 in | 40/100 · D |
Twitchell Dam · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Twitchell Dam is a temperate Köppen climate: Csb
Coldest-month mean 50.3°F and warmest-month mean 65.7°F place this station in temperate, dry-summer, warm summer climates (Csb). Class Csb is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: temperate, specifically temperate, dry-summer, warm summer.
- Köppen code
- Csb
- Group
- Temperate
- Warmest month
- 65.7°F
- Coldest month
- 50.3°F
Source: official public datasets monthly normals (1991–2020) at the city’s primary station. This is a station classification, not a mapped regional consensus.
National standing · heating-led station
Where Twitchell Dam sits across the climate record
Three NOAA fields for Twitchell Dam's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Top 30% warmest
- Among 6,861 stations, Twitchell Dam sits in the warmer third of annual means.
- Annual precipitation
- Drier than 75%
- Twitchell Dam's annual total ranks in the drier third of 6,352 measured normals.
- Seasonal temperature swing
- Narrower than 98%
- Warmest-to-coldest month gap for Twitchell Dam is compact versus 6,861 complete station-years.
How Twitchell Dam compares across U.S. station-mapped locations
Twitchell Dam's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
80 Top 24% score exceeds 76% of 6,189 station-mapped location scores
- 0–10: 0 station-mapped locations (0%). Below this entry.
- 10–20: 0 station-mapped locations (0%). Below this entry.
- 20–30: 96 station-mapped locations (2%). Below this entry.
- 30–40: 280 station-mapped locations (5%). Below this entry.
- 40–50: 1,113 station-mapped locations (18%). Below this entry.
- 50–60: 1,329 station-mapped locations (21%). Below this entry.
- 60–70: 1,236 station-mapped locations (20%). Below this entry.
- 70–80: 650 station-mapped locations (11%). Below this entry.
- 80–90: 921 station-mapped locations (15%). This entry sits in this band.
- 90–100: 564 station-mapped locations (9%). Above this entry.
Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 63°F (17°C) | 41°F (5°C) | 52°F (11°C) | 4.0" | 0.0" | 4.1 | 0.0 |
| February | 63°F (17°C) | 43°F (6°C) | 53°F (11°C) | 3.4" | 0.0" | 1.7 | 0.1 |
| March | 65°F (18°C) | 44°F (7°C) | 55°F (13°C) | 3.3" | 0.0" | 1.0 | 0.2 |
| April | 68°F (20°C) | 45°F (7°C) | 57°F (14°C) | 1.5" | 0.0" | 0.6 | 1.0 |
| May | 70°F (21°C) | 48°F (9°C) | 59°F (15°C) | 0.6" | 0.0" | 0.3 | 2.4 |
| June | 75°F (24°C) | 50°F (10°C) | 62°F (17°C) | 0.1" | 0.0" | 0.0 | 3.4 |
| July | 77°F (25°C) | 53°F (12°C) | 65°F (18°C) | 0.0" | 0.0" | 0.0 | 3.8 |
| August | 78°F (25°C) | 54°F (12°C) | 66°F (19°C) | 0.0" | 0.0" | 0.0 | 3.6 |
| September | 78°F (25°C) | 52°F (11°C) | 65°F (18°C) | 0.1" | 0.0" | 0.0 | 5.4 |
| October | 75°F (24°C) | 49°F (10°C) | 62°F (17°C) | 0.9" | 0.0" | 0.1 | 4.8 |
| November | 68°F (20°C) | 44°F (7°C) | 56°F (13°C) | 1.4" | 0.0" | 1.8 | 1.2 |
| December | 61°F (16°C) | 39°F (4°C) | 50°F (10°C) | 3.0" | 0.0" | 4.9 | 0.0 |
The year, day by day
The calendar barely moves in Twitchell Dam: no date carries a normal high of 90°F or a normal low at freezing. The year runs between 39°F near December 13 and 78°F near August 29.
No freezing date
Not one calendar date in the 1991–2020 record carries a normal low at or below 32°F. The coldest normal low of the year is 39°F around December 13.
Where the wet dates fall
The likeliest wet date is February 27, when 32% of years recorded at least a hundredth of an inch. The driest is July 23 at 1%. Summed across the calendar, that is about 51 wet dates a year.
The widest day
September 24 carries the biggest normal gap between afternoon and dawn, 27°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Twitchell Dam.
Monthly Precipitation
Average monthly rainfall and snowfall
7.7 days with precipitation
8.8 days with precipitation
8.4 days with precipitation
4.3 days with precipitation
2.4 days with precipitation
0.6 days with precipitation
0.4 days with precipitation
0.5 days with precipitation
0.8 days with precipitation
2.8 days with precipitation
5.2 days with precipitation
8.6 days with precipitation
Twitchell Dam's wet season runs through the cold months
December, January and February carry 57% of the year's precipitation here, while June through August contribute 1%. That is the cool-season-dominant pattern of the West Coast and the higher inland West, where storm tracks swing south in winter and summer turns dry; the thermometer meanwhile shows an unusually narrow 15.4°F seasonal spread.
- Wettest month
- January, 4.0"
- Driest month
- August, 0.0"
- Wettest three months
- January, February, March (59% of the year)
Shares are computed from this station's own 1991-2020 monthly precipitation normals. A cool-season label means the December-February share reaches 35%. Where snow falls, the monthly figures above report liquid-equivalent precipitation, so a wet winter month is not necessarily a rainy one.
When it rains in Twitchell Dam, it arrives in quantity
18.2" of precipitation falls across only about 50 wet days here, averaging 0.36 inches each. Fewer days carry more water: the year's total is delivered in comparatively heavy events rather than persistent damp.
- Days with measurable precipitation
- about 50 a year, 14% of all days
- Average depth per wet day
- 0.36 inches
- Most wet days
- February, about 9
- Fewest wet days
- July, about 0
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year, and a per-day average is not a forecast of any individual storm.
Twitchell Dam's record shows no measurable snowfall
This station measured snowfall across the 1991-2020 period and recorded none: the annual normal is 0.0 inches. That is a measured zero rather than missing data, which is a meaningful distinction here , most stations in the database simply do not report snow at all, and those pages say nothing about it.
A thirty-year normal of zero describes the typical year at this station. It is not a claim that snow has never fallen in the area.
Frost Dates & Growing Season
First Fall Freeze
December 4
50% probability date
Last Spring Freeze
February 4
50% probability date
Growing Season
303 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
2,706
Higher = more heating needed
Cooling Degree Days
314
Higher = more cooling needed
Warmest Month
August
Coldest Month
December
Nationwide similar cities
Other rankable U.S. places outside CA closest to Twitchell Dam on two NOAA annual-normal axes (mean temperature and annual precipitation). Chip rows use distinct link sets.
Closest by average temperature
Nearest out-of-state peers by annual mean temperature (58°F here).
- Camargo, OK 58°F · 0.0°F off
- Cornelia, GA 58°F · 0.0°F off
- Dayton, TN 58°F · 0.0°F off
- Decatur, TN 58°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (18.2" here), excluding temperature-peer places.
- Oral, SD 18.2" · 0.0" off
- Stanley, ID 18.2" · 0.0" off
- Russell Springs, KS 18.2" · 0.0" off
- Big Lake, TX 18.2" · 0.0" off
Data-derived climate profile
How Twitchell Dam's climate pattern fits together
heating led · dry · low swing
Heating is the larger measured load in Twitchell Dam, at 2,706 degree days versus 314 for cooling. Unlike a strongly continental record, however, its 15.4°F month-to-month range is compact; persistent cool-season demand matters more than a dramatic summer-to-winter reversal.
Twitchell Dam has a long frost-free window of roughly 303 days, but the dry annual profile is a separate constraint. Growing-season length says when freezes are unlikely, not whether rainfall is sufficient.
The calendar stays thermally compact and dry. August and December mark the typical warm and cold ends of the calendar, only 15.4°F apart, while the annual precipitation total remains below PlainClimate's dry threshold. The annual average is 58°F. The monthly rows show whether that limited precipitation is spread through the year or concentrated in a shorter interval.
Twitchell Dam's cold-season load does not imply a wet climate. Annual precipitation is 18.2 inches, which places the station in PlainClimate's dry range. Recorded annual snowfall is negligible. The snowfall and rainfall fields should be read separately rather than inferred from temperature.
These labels group NOAA 1991-2020 normals from Twitchell Dam's primary station, so the winter figures are a thirty-year average and not a floor: a single hard season can run well below them. Treat each band as a descriptive range for Twitchell Dam, not an official NOAA class or a year-ahead forecast.
Questions about Twitchell Dam's climate
How much rain does Twitchell Dam get? ▼
How much energy does heating and cooling require in Twitchell Dam? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Twitchell Dam's primary station: TWITCHELL DAM (USC00049111). For informational purposes only.
Place identity: U.S. Census Bureau 2024 Gazetteer places. The conservative exact name-and-state crosswalk finds no Census place match, so PlainClimate treats this as a station-mapped location and does not claim it is a municipality. No exact Gazetteer row for Twitchell Dam; facility counts that depend on place identity are therefore an upper bound, not a municipal census.
On this page every temperature, precipitation, and derived score for Twitchell Dam comes from its primary NOAA station record. No figure on this page is typed in by an editor - each value is rendered from NOAA 1991-2020 U.S. Climate Normals. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 1991–2020 normals.