Napa State Hospital, CA Climate: Temperature & Rain by Month
Explore NOAA NCEI's 1991–2020 climate normals → and a clearly labeled PlainClimate comfort calculation
30-year climate normals (1991-2020) from Napa State Hospital's primary NOAA station, NAPA STATE HOSPITAL.
The climate verdict for Napa State Hospital
A compact 20.5°F seasonal swing gives Napa State Hospital, California a steadier-than-extreme annual shape. NOAA reports an annual average of 60°F. It scores 97/100 for climate comfort (excellent), putting it in the top third of station-mapped location scores and exceeding 97% of them.
- 60°F
- annual average temperature (NOAA normal)
- 97/100
- comfort score, above 97% of station-mapped location scores
- 26.7"
- annual precipitation
- 295 days
- growing season, frost-free days
Napa State Hospital: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00046074 · Napa State Hospital, CA 60°F mean · 26.7" precip
TEMP-MILD · RANK-UPPER · PHOTO-FINISH · PRCP-MID · SWING-NARROW · COMF-TOP · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-MILD 60°F
- RANK-UPPER #5,214
- PHOTO-FINISH ≈ King City
- PRCP-MID 26.7"
- SWING-NARROW 21°F
- COMF-TOP 97/100
- LOAD-HEAT 2,358 HDD
- STN-1 USC00046074
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: King City, CA (+ 0 °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.
- Napa State Hosp… (this station) 60°F
- Cold Cachuma Lake, CA 60°F
- Hot Ben Lomond, CA 60°F
- Near King City, CA 60°F
- Near Gilroy, CA 60°F
Climate Living Index · Napa State Hospital
Napa State Hospital: 87/100 · grade A
Napa State Hospital publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Napa State Hospital, not an official NOAA rating. Rankings still use Comfort Score 97/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Frost-free season | 295 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 | 60.3°F · 7.2° from 67.5°F | 77/100 · B |
| Precipitation balance | 26.7 in · 8.3 from 35 in | 71/100 · B |
Napa State Hospital · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Napa State Hospital is a temperate Köppen climate: Csb
Coldest-month mean 49.1°F and warmest-month mean 69.6°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
- 69.6°F
- Coldest month
- 49.1°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 Napa State Hospital sits across the climate record
Three NOAA fields for Napa State Hospital's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Top 24% warmest
- Among 6,861 stations, Napa State Hospital sits in the warmer third of annual means.
- Annual precipitation
- 36th percentile wetness
- Neither arid nor torrential versus 6,352 station totals.
- Seasonal temperature swing
- Narrower than 97%
- Warmest-to-coldest month gap for Napa State Hospital is compact versus 6,861 complete station-years.
How Napa State Hospital compares across U.S. station-mapped locations
Napa State Hospital's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
97 Top 3% score exceeds 97% 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%). Below this entry.
- 90–100: 564 station-mapped locations (9%). This entry sits in this band.
Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020
Napa State Hospital's measured station temperature trend
MethodologyAcross 108 complete annual observations from 1878 to 2024, NAPA STATE HOSPITAL warmed at a fitted rate of 0.09°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- Napa State Hospital primary station fitted change +0.09 °C/decade
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 59°F (15°C) | 40°F (5°C) | 49°F (10°C) | 5.0" | 0.0" | 4.5 | 0.0 |
| February | 63°F (17°C) | 42°F (5°C) | 53°F (11°C) | 5.1" | 0.0" | 1.7 | 0.0 |
| March | 68°F (20°C) | 44°F (6°C) | 56°F (13°C) | 3.7" | 0.0" | 0.3 | 0.0 |
| April | 72°F (22°C) | 46°F (8°C) | 59°F (15°C) | 1.7" | 0.0" | 0.1 | 0.7 |
| May | 77°F (25°C) | 50°F (10°C) | 63°F (17°C) | 1.1" | 0.0" | 0.0 | 2.6 |
| June | 82°F (28°C) | 54°F (12°C) | 68°F (20°C) | 0.3" | 0.0" | 0.0 | 6.0 |
| July | 83°F (29°C) | 56°F (13°C) | 69°F (21°C) | 0.0" | 0.0" | 0.0 | 5.6 |
| August | 84°F (29°C) | 56°F (13°C) | 70°F (21°C) | 0.1" | 0.0" | 0.0 | 6.4 |
| September | 84°F (29°C) | 53°F (12°C) | 69°F (21°C) | 0.1" | 0.0" | 0.0 | 8.3 |
| October | 78°F (26°C) | 49°F (10°C) | 64°F (18°C) | 1.3" | 0.0" | 0.0 | 2.9 |
| November | 66°F (19°C) | 44°F (6°C) | 55°F (13°C) | 2.8" | 0.0" | 0.8 | 0.0 |
| December | 59°F (15°C) | 40°F (4°C) | 49°F (10°C) | 5.5" | 0.0" | 4.9 | 0.0 |
The year, day by day
The calendar barely moves in Napa State Hospital: no date carries a normal high of 90°F or a normal low at freezing. The year runs between 39°F near December 23 and 85°F near September 3.
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 23.
Where the wet dates fall
The likeliest wet date is January 17, when 39% of years recorded at least a hundredth of an inch. The driest is July 23 at 0%. Summed across the calendar, that is about 69 wet dates a year.
The widest day
September 16 carries the biggest normal gap between afternoon and dawn, 31°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Napa State Hospital.
Monthly Precipitation
Average monthly rainfall and snowfall
12.0 days with precipitation
10.8 days with precipitation
9.6 days with precipitation
6.5 days with precipitation
3.7 days with precipitation
1.1 days with precipitation
0.0 days with precipitation
0.2 days with precipitation
1.0 days with precipitation
3.6 days with precipitation
8.2 days with precipitation
11.6 days with precipitation
Napa State Hospital's wet season runs through the cold months
December, January and February carry 59% 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 20.5°F seasonal spread.
- Wettest month
- December, 5.5"
- Driest month
- July, 0.0"
- Wettest three months
- December, February, January (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 Napa State Hospital, it arrives in quantity
26.7" of precipitation falls across only about 68 wet days here, averaging 0.39 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 68 a year, 19% of all days
- Average depth per wet day
- 0.39 inches
- Most wet days
- January, about 12
- 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.
Napa State Hospital'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 12
50% probability date
Growing Season
295 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
2,358
Higher = more heating needed
Cooling Degree Days
643
Higher = more cooling needed
Warmest Month
August
Coldest Month
December
Nationwide similar cities
Other rankable U.S. places outside CA closest to Napa State Hospital 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 (60°F here).
- Albemarle, NC 60°F · 0.0°F off
- Caruthersville, MO 60°F · 0.0°F off
- Fort Cobb, OK 60°F · 0.0°F off
- Lindsay, OK 60°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (26.7" here), excluding temperature-peer places.
- Gregory, SD 26.7" · 0.0" off
- Grand Island, NE 26.6" · 0.1" off
- Mutual, OK 26.7" · 0.1" off
- Cooke City, MT 26.6" · 0.1" off
Data-derived climate profile
How Napa State Hospital's climate pattern fits together
heating led · moderate · low swing
Heating is the larger measured load in Napa State Hospital, at 2,358 degree days versus 643 for cooling. Unlike a strongly continental record, however, its 20.5°F month-to-month range is compact; persistent cool-season demand matters more than a dramatic summer-to-winter reversal.
The frost-free window extends for about 295 days. That is a long calendar measure, but it is not a forecast and does not combine heat, rainfall, soil, or local elevation into a planting recommendation.
Temperature varies within a narrow 20.5°F band across the normal year. August and December mark the typical warm and cold ends of the calendar. The annual average is 60°F. Monthly rows still matter, but they refine a steady profile rather than reveal two climatic extremes.
Napa State Hospital's 26.7 inches of annual precipitation falls in PlainClimate's middle band, so “wet” or “dry” is not the leading description. Recorded annual snowfall is negligible. Temperature balance and the calendar distribution carry more information than the annual moisture label alone.
These labels group NOAA 1991-2020 normals from Napa State Hospital'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 Napa State Hospital, not an official NOAA class or a year-ahead forecast.
Questions about Napa State Hospital's climate
How much rain does Napa State Hospital get? ▼
How many days above 90°F does Napa State Hospital get? ▼
How much energy does heating and cooling require in Napa State Hospital? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Napa State Hospital's primary station: NAPA STATE HOSPITAL (USC00046074). 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 Napa State Hospital; 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 Napa State Hospital 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.