Key West, FL Climate: Temperature & Rain by Month
Average temperature and precipitation from NOAA NCEI 1991–2020 normals →, with a derived climate comfort score
30-year climate normals (1991-2020) from Key West's primary NOAA station, KEY WEST NAS - 2 stations mapped to the area.
The climate verdict for Key West
Warm-season cooling demand defines Key West, Florida, running at more than twice its heating total. The NOAA normal records an annual average of 79°F. It scores 88/100 for climate comfort (excellent), putting it in the top third of station-mapped location scores and exceeding 89% of them.
- 79°F
- yearly average temperature, NOAA normal
- 88/100
- comfort score, above 89% of station-mapped location scores
- 43.6"
- precipitation, annual total
Key West: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USW00012850 · Key West, FL 79°F mean · 43.6" precip
TEMP-HOT · RANK-WARM · PHOTO-FINISH · PRCP-MID · SWING-NARROW · COMF-TOP · LOAD-COOL · STN-MULTI · BOOK-FULL
- TEMP-HOT 79°F
- RANK-WARM #6,792
- PHOTO-FINISH ≈ Kailua Kona Ke-…
- PRCP-MID 43.6"
- SWING-NARROW 15°F
- COMF-TOP 88/100
- LOAD-COOL 5,114 CDD
- STN-MULTI USW00012850
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Kailua Kona Ke-ahole, HI ( -0.6 °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 FL station list.
- Key West (this station) 79°F
- Cold Curry Hammock S…, FL 78°F
- Near Kailua Kona Ke-…, HI 78°F
- Near Islamorada, FL 78°F
- Near Tavernier, FL 78°F
Key West sits in Florida, the #1 hottest U.S. state at 72.6°F statewide annual average - see all 50 hottest states ranked by NOAA normals
Climate Living Index · Key West
Key West: 67/100 · grade C
Key West publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals · NOAA hourly normals); 1 missing weight rescale to 100.
PlainClimate-derived for Key West, not an official NOAA rating. Rankings still use Comfort Score 88/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Normal heat + freeze calendar | 19 calendar days | 98/100 · A |
| Snowfall burden | 0.0 inches/year | 90/100 · A |
| Precipitation balance | 43.6 in · 8.6 from 35 in | 70/100 · B |
| Annual temperature balance | 78.8°F · 11.3° from 67.5°F | 64/100 · C |
| Summer moisture balance | 74.8°F mean dew point | 0/100 · F |
Key West · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Key West stays in the tropical Köppen band: Aw
Year-round heat with a pronounced dry season: tropical savanna (Aw). Class Aw is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: tropical, specifically tropical savanna.
- Köppen code
- Aw
- Group
- Tropical
- Warmest month
- 85.4°F
- Coldest month
- 70.5°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 Key West sits across the climate record
Three NOAA fields for Key West's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Top 1% warmest
- Among 6,861 stations, Key West sits in the warmer third of annual means.
- Annual precipitation
- 66th percentile wetness
- Neither arid nor torrential versus 6,352 station totals.
- Seasonal temperature swing
- Narrower than 98%
- Warmest-to-coldest month gap for Key West is compact versus 6,861 complete station-years.
How Key West compares across U.S. station-mapped locations
Key West's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
88 Top 11% score exceeds 89% 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
Key West's measured station temperature trend
MethodologyAcross 37 complete annual observations from 1954 to 2018, KEY WEST NAS 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.
- Key West 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 | 75°F (24°C) | 66°F (19°C) | 71°F (21°C) | 2.1" | 0.0" | 0.0 | 0.0 |
| February | 77°F (25°C) | 68°F (20°C) | 72°F (22°C) | 1.5" | 0.0" | 0.0 | 0.0 |
| March | 79°F (26°C) | 70°F (21°C) | 75°F (24°C) | 1.4" | 0.0" | 0.0 | 0.0 |
| April | 83°F (28°C) | 73°F (23°C) | 78°F (26°C) | 2.4" | 0.0" | 0.0 | 0.4 |
| May | 86°F (30°C) | 77°F (25°C) | 81°F (27°C) | 3.4" | 0.0" | 0.0 | 2.3 |
| June | 88°F (31°C) | 80°F (27°C) | 84°F (29°C) | 4.9" | 0.0" | 0.0 | 11.9 |
| July | 90°F (32°C) | 81°F (27°C) | 85°F (30°C) | 4.3" | 0.0" | 0.0 | 21.7 |
| August | 90°F (32°C) | 81°F (27°C) | 85°F (30°C) | 5.5" | 0.0" | 0.0 | 23.5 |
| September | 89°F (31°C) | 80°F (27°C) | 84°F (29°C) | 8.1" | 0.0" | 0.0 | 15.4 |
| October | 85°F (30°C) | 78°F (25°C) | 82°F (28°C) | 5.7" | 0.0" | 0.0 | 4.0 |
| November | 80°F (27°C) | 73°F (23°C) | 77°F (25°C) | 2.3" | 0.0" | 0.0 | 0.7 |
| December | 77°F (25°C) | 69°F (20°C) | 73°F (23°C) | 1.9" | 0.0" | 0.0 | 0.0 |
The year, day by day
The year in Key West runs from a mild 65°F around January 18 to 90°F at the peak near August 5, and the normal low never reaches freezing on any date in the record.
When the heat sits
Normal highs reach 90°F from July 31 through August 18, covering 19 dates. The broader mild season, normal highs of 70°F or more, runs January 1 to December 31.
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 65°F around January 18.
Where the wet dates fall
The likeliest wet date is September 10, when 49% of years recorded at least a hundredth of an inch. The driest is March 29 at 14%. Summed across the calendar, that is about 103 wet dates a year.
The widest day
January 26 carries the biggest normal gap between afternoon and dawn, 10°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Key West.
Where Key West Stands Nationally
Among the steadiest day-night climates ranked: even the widest normal daily swing holds to roughly 10°F.
Key West earns one nationally notable standing (outer quintile) against 6,860 NOAA 1991–2020 normals stations, middle-of-the-pack metrics stay silent here.
Monthly Precipitation
Average monthly rainfall and snowfall
7.8 days with precipitation
5.3 days with precipitation
4.6 days with precipitation
4.8 days with precipitation
6.9 days with precipitation
10.3 days with precipitation
10.6 days with precipitation
13.0 days with precipitation
14.7 days with precipitation
11.8 days with precipitation
5.7 days with precipitation
6.4 days with precipitation
Key West spreads its precipitation across the year
Neither half of the year dominates here: June through August take 34% of the annual total and December through February 13%, with neither reaching the 35% that would mark a distinct wet season. Key West has no dry season to plan around, though it does carry an unusually narrow 14.9°F seasonal spread.
The gap between the wettest and driest month still matters: September averages 8.1" and March 1.4". The three wettest months together take 44% of the year, against the 25% a perfectly flat distribution would give them.
Shares are computed from this station's own 1991-2020 monthly precipitation normals. "Spread across the year" means neither the June-August nor the December-February share reaches 35%; it describes an average year, not the variability of any single one.
When it rains in Key West, it arrives in quantity
43.6" of precipitation falls across only about 102 wet days here, averaging 0.43 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 102 a year, 28% of all days
- Average depth per wet day
- 0.43 inches
- Most wet days
- September, about 15
- Fewest wet days
- March, about 5
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.
Key West'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
N/A
50% probability date
Last Spring Freeze
N/A
50% probability date
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
47
Higher = more heating needed
Cooling Degree Days
5,114
Higher = more cooling needed
Warmest Month
August
Coldest Month
January
Humidity & Wind
Monthly averages from hourly observations
| Month | Humidity | Wind (mph) | Clear Sky % | Overcast % |
|---|---|---|---|---|
| January | 75% | 10.2 | 13% | 8% |
| February | 73% | 10.3 | 18% | 6% |
| March | 70% | 10.8 | 18% | 4% |
| April | 69% | 10.8 | 17% | 5% |
| May | 73% | 9.1 | 13% | 7% |
| June | 72% | 8.5 | 11% | 7% |
| July | 72% | 8.2 | 10% | 6% |
| August | 74% | 8.2 | 20% | 6% |
| September | 74% | 9.0 | 9% | 8% |
| October | 72% | 10.6 | 6% | 6% |
| November | 74% | 9.9 | 14% | 6% |
| December | 75% | 10.1 | 16% | 8% |
Nationwide similar cities
Other rankable U.S. places outside FL closest to Key West 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 (79°F here).
- Kahului, HI 77°F · 1.7°F off
- Lihue, HI 76°F · 2.5°F off
- Brownsville, TX 76°F · 2.6°F off
- Needles, CA 76°F · 2.6°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (43.6" here), excluding temperature-peer places.
- Buchanan, VA 43.6" · 0.0" off
- Lynchburg, VA 43.6" · 0.0" off
- Charlotte, NC 43.6" · 0.0" off
- Boston, MA 43.6" · 0.0" off
Data-derived climate profile
How Key West's climate pattern fits together
cooling led · moderate · low swing
Warm-season load persists through a relatively even calendar in Key West. Cooling totals 5,114 degree days, more than double the 47 heating measure, and the 14.9°F seasonal range is compact rather than sharply divided.
Key West's 43.6 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.
Temperature varies within a narrow 14.9°F band across the normal year. August and January mark the typical warm and cold ends of the calendar. The annual average is 79°F. Monthly rows still matter, but they refine a steady profile rather than reveal two climatic extremes.
A frost-free growing-season length is not available for Key West. That missing field is kept separate from the observed temperature and precipitation record rather than filled from a regional estimate.
These labels group NOAA 1991-2020 normals from Key West's primary station, so the summer figures are a thirty-year average rather than a ceiling: individual years have run hotter and will again. For Key West that means a descriptive range only — not an official NOAA classification and not a prediction for next summer.
Questions about Key West's climate
How much rain does Key West get? ▼
How many days above 90°F does Key West get? ▼
How much energy does heating and cooling require in Key West? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Key West's primary station: KEY WEST NAS (USW00012850). 2 NOAA stations are mapped to the Key West area; the primary station's record is used for consistency. 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 1236550). Match rule for Key West: 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 Key West 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.