Imperial, CA Climate: Temperature & Rain by Month
Temperature and precipitation from NOAA NCEI 1991–2020 normals →, plus PlainClimate's derived comfort score
30-year climate normals (1991-2020) from Imperial's primary NOAA station, IMPERIAL.
The climate verdict for Imperial
Imperial, California is cooling-led and dry. Its 2.8 inches of annual precipitation pairs with an annual average of 73°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.
- 73°F
- annual average temperature (NOAA normal)
- 80/100
- comfort score, above 76% of station-mapped location scores
- 2.8"
- yearly precipitation total
- 356 days
- frost-free days per growing season
Imperial: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00044223 · Imperial, CA 73°F mean · 2.8" precip
TEMP-HOT · RANK-WARM · PHOTO-FINISH · PRCP-ARID · SWING-MID · COMF-TOP · LOAD-COOL · STN-1 · BOOK-FULL
- TEMP-HOT 73°F
- RANK-WARM #6,655
- PHOTO-FINISH ≈ Yuma
- PRCP-ARID 2.8"
- SWING-MID 37°F
- COMF-TOP 80/100
- LOAD-COOL 3,921 CDD
- STN-1 USC00044223
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Yuma, AZ (+ 0.2 °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.
- Imperial (this station) 73°F
- Cold Castle Hot Spri…, AZ 73°F
- Hot Kingsville Naas, TX 73°F
- Near Yuma, AZ 73°F
- Near Crystal City, TX 73°F
Climate Living Index · Imperial
Imperial: 59/100 · grade C
Imperial publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Imperial, not an official NOAA rating. Rankings still use Comfort Score 80/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Frost-free season | 356 days/year | 100/100 · A |
| Snowfall burden | 0.0 inches/year | 90/100 · A |
| Annual temperature balance | 73.0°F · 5.5° from 67.5°F | 83/100 · B |
| Normal heat + freeze calendar | 159 calendar days | 40/100 · D |
| Precipitation balance | 2.8 in · 32.2 from 35 in | 0/100 · F |
Imperial · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Imperial's normals sit in a dry climate class: BWh
Annual precipitation falls well below the aridity threshold for this temperature regime, so the normals classify as hot desert (BWh). Class BWh is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: dry (arid or semi-arid), specifically hot desert.
- Köppen code
- BWh
- Group
- Dry (arid or semi-arid)
- Warmest month
- 91.4°F
- Coldest month
- 54.9°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 · cooling-led station
Where Imperial sits across the climate record
Three NOAA fields for Imperial's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Top 3% warmest
- Among 6,861 stations, Imperial sits in the warmer third of annual means.
- Annual precipitation
- Drier than 100%
- Imperial's annual total ranks in the drier third of 6,352 measured normals.
- Seasonal temperature swing
- Narrower than 78%
- Warmest-to-coldest month gap for Imperial is compact versus 6,861 complete station-years.
How Imperial compares across U.S. station-mapped locations
Imperial'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
Imperial's measured station temperature trend
MethodologyAcross 79 complete annual observations from 1905 to 2025, IMPERIAL warmed at a fitted rate of 0.17°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- Imperial primary station fitted change +0.17 °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 | 69°F (20°C) | 43°F (6°C) | 56°F (13°C) | 0.5" | 0.0" | 1.4 | 0.0 |
| February | 72°F (22°C) | 47°F (8°C) | 59°F (15°C) | 0.4" | 0.0" | 0.4 | 0.0 |
| March | 78°F (26°C) | 52°F (11°C) | 65°F (18°C) | 0.3" | 0.0" | 0.0 | 3.5 |
| April | 84°F (29°C) | 56°F (14°C) | 70°F (21°C) | 0.1" | 0.0" | 0.0 | 10.9 |
| May | 93°F (34°C) | 63°F (17°C) | 78°F (25°C) | 0.1" | 0.0" | 0.0 | 23.3 |
| June | 101°F (38°C) | 70°F (21°C) | 85°F (30°C) | 0.0" | 0.0" | 0.0 | 28.9 |
| July | 104°F (40°C) | 77°F (25°C) | 91°F (33°C) | 0.1" | 0.0" | 0.0 | 31.0 |
| August | 105°F (40°C) | 78°F (26°C) | 91°F (33°C) | 0.2" | 0.0" | 0.0 | 31.0 |
| September | 100°F (38°C) | 73°F (23°C) | 87°F (30°C) | 0.3" | 0.0" | 0.0 | 28.8 |
| October | 89°F (32°C) | 61°F (16°C) | 75°F (24°C) | 0.2" | 0.0" | 0.0 | 19.0 |
| November | 77°F (25°C) | 50°F (10°C) | 63°F (17°C) | 0.2" | 0.0" | 0.2 | 2.0 |
| December | 68°F (20°C) | 42°F (6°C) | 55°F (13°C) | 0.4" | 0.0" | 1.7 | 0.0 |
The year, day by day
The year in Imperial runs from a mild 42°F around December 19 to 105°F at the peak near August 8, and the normal low never reaches freezing on any date in the record.
When the heat sits
Normal highs reach 90°F from May 8 through October 13, covering 159 dates. The broader mild season, normal highs of 70°F or more, runs January 29 to December 1.
This counts calendar dates whose 1991–2020 normal high reaches 90°F. It is a smaller number than the 90°F+ day counts in the monthly table above, which measure how often the threshold was actually crossed in a typical year. A date can average 88°F and still exceed 90°F in half of all years.
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 42°F around December 19.
Where the wet dates fall
The likeliest wet date is January 5, when 11% of years recorded at least a hundredth of an inch. The driest is June 13 at 0%. Summed across the calendar, that is about 17 wet dates a year.
The widest day
June 6 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 Imperial.
Where Imperial Stands Nationally
Summers here run among the most heat-heavy normals calendars in the country: on about 159 days a year the normal daily high itself reaches 90°F — a count fewer than one station in ten exceeds.
Aridity defines the water calendar: about 3 inches in a normal year lands this among the driest tenth of ranked stations.
Imperial earns 2 nationally notable standings (outer quintiles) against 6,860 NOAA 1991–2020 normals stations; only those extremes render.
Monthly Precipitation
Average monthly rainfall and snowfall
3.2 days with precipitation
2.7 days with precipitation
1.9 days with precipitation
0.7 days with precipitation
0.3 days with precipitation
0.1 days with precipitation
0.8 days with precipitation
1.4 days with precipitation
1.1 days with precipitation
0.9 days with precipitation
1.3 days with precipitation
2.8 days with precipitation
Imperial's wet season runs through the cold months
December, January and February carry 47% of the year's precipitation here, while June through August contribute 12%. 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 a 36.5°F seasonal spread.
- Wettest month
- January, 0.5"
- Driest month
- June, 0.0"
- Wettest three months
- January, February, December (47% 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.
Imperial is dry, and what does fall arrives gently
Only about 17 days a year record measurable precipitation here, 5% of the calendar, and they carry 2.8" between them. At roughly 0.16 inches on an average wet day, this is not the damp drizzle of a marine climate; it is an arid record in which precipitation is both uncommon and light when it appears.
The wettest month by count is January at about 3 wet days; the driest is June at about 0.
A low per-event average in a dry record is a statement about typical days only. Arid regions can still take a large share of a year's total from a single convective storm, which a normal cannot show.
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year, not the extremes within it.
Imperial'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 26
50% probability date
Last Spring Freeze
January 4
50% probability date
Growing Season
356 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
974
Higher = more heating needed
Cooling Degree Days
3,921
Higher = more cooling needed
Warmest Month
August
Coldest Month
December
Nationwide similar cities
Other rankable U.S. places outside CA closest to Imperial 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 (73°F here).
- Corpus Christi, TX 73°F · 0.0°F off
- Orlando, FL 73°F · 0.0°F off
- Bartow, FL 73°F · 0.1°F off
- Melbourne, FL 73°F · 0.1°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (2.8" here), excluding temperature-peer places.
- Yuma Proving Ground, AZ 3.5" · 0.8" off
- Wendover, UT 3.6" · 0.8" off
- Tacna, AZ 3.8" · 1.0" off
- Yuma, AZ 4.0" · 1.2" off
Scarce-water calendar
Where Imperial's limited precipitation lands
cooling led · dry · mid swing
Air-conditioning demand is the clearest thermal signal here. Imperial accumulates 3,921 cooling degree days, more than twice its 974 heating total; the monthly table shows when that imbalance builds rather than treating it as a year-round condition.
Heat demand sits beside limited local precipitation: Imperial receives 2.8 inches in a normal year, inside PlainClimate's dry range. Recorded annual snowfall is negligible. Month-level precipitation is the useful check on when that small annual total arrives.
August and December mark the typical warm and cold ends of the calendar in Imperial's middle-range seasonal profile. The measured spread is 36.5°F. The annual average is 73°F. Neither the annual mean nor one extreme month represents the full calendar on its own.
With about 356 frost-free days, the calendar is constrained more by sustained heat than by freeze timing. This does not measure crop suitability or soil moisture; it only reports the NOAA-derived frost-free window for Imperial.
Imperial wettest normal
January
January concentrates the scarce annual total (2.8 inches).
Imperial driest normal
June
June is typically driest; arid stations are defined by when water is absent, not by a four-season grid.
Questions about Imperial's climate
How dry is Imperial? ▼
How many days above 90°F does Imperial get? ▼
How much energy does heating and cooling require in Imperial? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Imperial's primary station: IMPERIAL (USC00044223). For informational purposes only.
Place identity: U.S. Census Bureau 2024 Gazetteer places. The 2024 Census Gazetteer identifies the exact name-and-state match as an incorporated place (GEOID 0636280). Match rule for Imperial: exact normalized name + state only, no fuzzy expansion, so nearby differently spelled facilities stay unmatched.
On this page every temperature, precipitation, and derived score for Imperial 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.