Key West weather in March
In March, Key West sees average daytime highs of 74°F and overnight lows near 71°F, with 1.0 in of rain across 4.2 wet days and about 11.8 hours of daylight. It is the 10th-warmest and 12th-wettest month of the year here.
Day-to-day highs hold fairly steady near 74°F through the month. The sky is clear or mostly clear about 68% of the time in March, and the air most often feels muggy.
Daylight stretches from about 11 h 30 min at the start of March to 12 h 12 min by month's end. Set against the rest of the year, March is Key West's 1st-clearest and 4th-windiest month. For the whole year in context, see Key West's year-round climate.
- Daytime high
- 74°
- 10th warmest
- Overnight low
- 71°
- 4th coldest
- Rainfall
- 1.0 in
- 4.2 wet days
- Daylight
- 11 h 48 min
- 6:42 AM – 6:31 PM
- Cloud cover
- 32%
- 1st clearest
- Wind
- 14 mph
- 4th windiest
- Solar energy
- 5.93 kWh/m²
- Travel score
- 8.4
- out of 10
Key West is county seat of Monroe County, Florida, United States.
- Density
- 1,373/km²
- people per km²
- Founded
- 1828
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Temperature in March
Day-to-day highs hold fairly steady near 74°F through the month.
A typical March day in Key West reaches about 74°F in the afternoon and slips back to 71°F overnight — a 3°F spread between the day's warmth and the night's chill. On most days the high lands between 70°F and 78°F. Set against its neighbours, March runs about 1°F warmer than February and about 2°F cooler than April.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°F) | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 75 | 75 | 75 | 75 | 75 | 75 | 75 | 75 | 75 | 76 | 76 | 76 |
| Avg low (°F) | 71 | 71 | 71 | 71 | 71 | 71 | 71 | 71 | 71 | 71 | 71 | 71 | 71 | 71 | 71 | 71 | 71 | 71 | 72 | 72 | 72 | 72 | 72 | 72 | 72 | 73 | 73 | 73 | 73 | 73 | 73 |
| Avg high (°F) | Avg low (°F) | |
|---|---|---|
| 1 | 74 | 71 |
| 2 | 74 | 71 |
| 3 | 74 | 71 |
| 4 | 74 | 71 |
| 5 | 74 | 71 |
| 6 | 74 | 71 |
| 7 | 74 | 71 |
| 8 | 74 | 71 |
| 9 | 74 | 71 |
| 10 | 74 | 71 |
| 11 | 74 | 71 |
| 12 | 74 | 71 |
| 13 | 74 | 71 |
| 14 | 74 | 71 |
| 15 | 74 | 71 |
| 16 | 74 | 71 |
| 17 | 74 | 71 |
| 18 | 74 | 71 |
| 19 | 74 | 72 |
| 20 | 75 | 72 |
| 21 | 75 | 72 |
| 22 | 75 | 72 |
| 23 | 75 | 72 |
| 24 | 75 | 72 |
| 25 | 75 | 72 |
| 26 | 75 | 73 |
| 27 | 75 | 73 |
| 28 | 75 | 73 |
| 29 | 76 | 73 |
| 30 | 76 | 73 |
| 31 | 76 | 73 |
How March really feels in Key West
Once humidity and wind are folded in, March averages 0 days that feel above 90°F and 0 that feel at or below 32°F — the comfort signal a plain temperature reading hides.
March sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.
Key West weather by month
How March compares with the rest of the year at a glance. March is the 10th-warmest and 12th-wettest month here — the current month is highlighted below.
| Month | High / Low (°F) | Rainfall (inches) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 73° / 69° | 1.5 | 5.7 | 10.6 | 7.8 |
| Feb | 73° / 70° | 1.2 | 4 | 11.1 | 8.1 |
| Mar | 74° / 71° | 1.0 | 4.2 | 11.8 | 8.4 |
| Apr | 77° / 74° | 1.5 | 4.5 | 12.6 | 8.3 |
| May | 80° / 77° | 2.6 | 7.9 | 13.2 | 7.3 |
| Jun | 83° / 80° | 4.1 | 12.7 | 13.5 | 5.7 |
| Jul | 84° / 81° | 2.5 | 12.9 | 13.4 | 5.3 |
| Aug | 84° / 81° | 4.1 | 16.1 | 12.9 | 4.8 |
| Sep | 83° / 80° | 5.4 | 17.7 | 12.2 | 4.7 |
| Oct | 81° / 78° | 4.6 | 12.7 | 11.4 | 6.2 |
| Nov | 77° / 74° | 1.5 | 5.8 | 10.8 | 7.8 |
| Dec | 75° / 71° | 1.3 | 5.1 | 10.5 | 8.0 |
Cloud cover in March
The sky is clear or mostly clear about 68% of the time in March, the clearest month of the year.
Beyond those clear spells, partly cloudy skies cover about 13% of March, with mostly cloudy or overcast conditions the remaining 19%. Skies tend to open up as the month goes on.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 79 | 78 | 78 | 78 | 78 | 77 | 77 | 77 | 77 | 78 | 79 | 79 | 79 | 79 | 80 | 81 | 81 | 81 | 82 | 83 | 83 | 84 | 84 | 84 | 84 | 83 | 83 | 83 | 83 | 83 | 82 |
| Cloudier (%) | 21 | 22 | 22 | 22 | 22 | 23 | 23 | 23 | 23 | 22 | 21 | 21 | 21 | 21 | 20 | 19 | 19 | 19 | 18 | 17 | 17 | 16 | 16 | 16 | 16 | 17 | 17 | 17 | 17 | 17 | 18 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| 1 | 79 | 21 |
| 2 | 78 | 22 |
| 3 | 78 | 22 |
| 4 | 78 | 22 |
| 5 | 78 | 22 |
| 6 | 77 | 23 |
| 7 | 77 | 23 |
| 8 | 77 | 23 |
| 9 | 77 | 23 |
| 10 | 78 | 22 |
| 11 | 79 | 21 |
| 12 | 79 | 21 |
| 13 | 79 | 21 |
| 14 | 79 | 21 |
| 15 | 80 | 20 |
| 16 | 81 | 19 |
| 17 | 81 | 19 |
| 18 | 81 | 19 |
| 19 | 82 | 18 |
| 20 | 83 | 17 |
| 21 | 83 | 17 |
| 22 | 84 | 16 |
| 23 | 84 | 16 |
| 24 | 84 | 16 |
| 25 | 84 | 16 |
| 26 | 83 | 17 |
| 27 | 83 | 17 |
| 28 | 83 | 17 |
| 29 | 83 | 17 |
| 30 | 83 | 17 |
| 31 | 82 | 18 |
Chance of precipitation in March
Key West gets around 1.0 in of rain over 4.2 wet days in March, the driest month. The line is the day-by-day chance of measurable precipitation.
Day to day, the chance of measurable rain averages around 14% and peaks near 15% on the wettest days.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain chance (%) | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 15 | 15 | 15 | 15 | 15 | 15 | 15 | 15 | 15 | 15 | 14 | 14 | 14 | 13 | 13 | 12 | 12 | 12 | 12 | 11 | 11 |
| Rain chance (%) | |
|---|---|
| 1 | 14 |
| 2 | 14 |
| 3 | 14 |
| 4 | 14 |
| 5 | 14 |
| 6 | 14 |
| 7 | 14 |
| 8 | 14 |
| 9 | 14 |
| 10 | 14 |
| 11 | 15 |
| 12 | 15 |
| 13 | 15 |
| 14 | 15 |
| 15 | 15 |
| 16 | 15 |
| 17 | 15 |
| 18 | 15 |
| 19 | 15 |
| 20 | 15 |
| 21 | 14 |
| 22 | 14 |
| 23 | 14 |
| 24 | 13 |
| 25 | 13 |
| 26 | 12 |
| 27 | 12 |
| 28 | 12 |
| 29 | 12 |
| 30 | 11 |
| 31 | 11 |
Humidity in March
Most of March feels muggy — the stacked bands show each day's mix of comfort levels, read off the dew point.
By dew point, March lands in the muggy band about 34% of days. Sticky, muggy-or-worse air turns up on roughly 53% of them.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 12 | 12 | 13 | 13 | 13 | 13 | 13 | 13 | 13 | 12 | 12 | 11 | 11 | 10 | 10 | 9 | 9 | 9 | 8 | 8 | 8 | 7 | 7 | 7 | 6 | 6 | 6 | 5 | 5 | 5 | 4 |
| Comfortable (%) | 16 | 17 | 17 | 18 | 18 | 19 | 19 | 19 | 19 | 19 | 19 | 19 | 19 | 18 | 18 | 17 | 17 | 16 | 15 | 15 | 14 | 13 | 13 | 12 | 12 | 11 | 11 | 11 | 11 | 10 | 10 |
| Humid (%) | 19 | 19 | 19 | 20 | 20 | 20 | 20 | 20 | 20 | 20 | 20 | 21 | 21 | 21 | 21 | 21 | 22 | 22 | 22 | 23 | 23 | 24 | 25 | 25 | 25 | 26 | 26 | 25 | 25 | 25 | 25 |
| Muggy (%) | 34 | 33 | 33 | 32 | 32 | 32 | 32 | 32 | 32 | 33 | 33 | 34 | 34 | 35 | 35 | 36 | 36 | 36 | 36 | 36 | 35 | 35 | 34 | 34 | 34 | 33 | 33 | 33 | 33 | 32 | 32 |
| Oppressive (%) | 19 | 19 | 18 | 17 | 17 | 16 | 16 | 16 | 16 | 15 | 15 | 15 | 15 | 15 | 16 | 16 | 16 | 17 | 17 | 18 | 19 | 20 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 |
| Miserable (%) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| Dry (%) | Comfortable (%) | Humid (%) | Muggy (%) | Oppressive (%) | Miserable (%) | |
|---|---|---|---|---|---|---|
| 1 | 12 | 16 | 19 | 34 | 19 | 0 |
| 2 | 12 | 17 | 19 | 33 | 19 | 0 |
| 3 | 13 | 17 | 19 | 33 | 18 | 0 |
| 4 | 13 | 18 | 20 | 32 | 17 | 0 |
| 5 | 13 | 18 | 20 | 32 | 17 | 0 |
| 6 | 13 | 19 | 20 | 32 | 16 | 0 |
| 7 | 13 | 19 | 20 | 32 | 16 | 0 |
| 8 | 13 | 19 | 20 | 32 | 16 | 0 |
| 9 | 13 | 19 | 20 | 32 | 16 | 0 |
| 10 | 12 | 19 | 20 | 33 | 15 | 0 |
| 11 | 12 | 19 | 20 | 33 | 15 | 0 |
| 12 | 11 | 19 | 21 | 34 | 15 | 0 |
| 13 | 11 | 19 | 21 | 34 | 15 | 0 |
| 14 | 10 | 18 | 21 | 35 | 15 | 0 |
| 15 | 10 | 18 | 21 | 35 | 16 | 1 |
| 16 | 9 | 17 | 21 | 36 | 16 | 1 |
| 17 | 9 | 17 | 22 | 36 | 16 | 1 |
| 18 | 9 | 16 | 22 | 36 | 17 | 1 |
| 19 | 8 | 15 | 22 | 36 | 17 | 1 |
| 20 | 8 | 15 | 23 | 36 | 18 | 1 |
| 21 | 8 | 14 | 23 | 35 | 19 | 1 |
| 22 | 7 | 13 | 24 | 35 | 20 | 1 |
| 23 | 7 | 13 | 25 | 34 | 20 | 1 |
| 24 | 7 | 12 | 25 | 34 | 21 | 1 |
| 25 | 6 | 12 | 25 | 34 | 22 | 1 |
| 26 | 6 | 11 | 26 | 33 | 23 | 1 |
| 27 | 6 | 11 | 26 | 33 | 24 | 1 |
| 28 | 5 | 11 | 25 | 33 | 25 | 1 |
| 29 | 5 | 11 | 25 | 33 | 26 | 1 |
| 30 | 5 | 10 | 25 | 32 | 27 | 1 |
| 31 | 4 | 10 | 25 | 32 | 28 | 1 |
Wind in March
Winds average 14 mph in March.
Across March, daily wind ranges from about 13 mph on the calmest days to 14 mph at its breeziest. It stays fairly steady from day to day.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (mph) | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 13 | 13 | 13 | 13 | 13 | 13 | 13 | 13 |
| Feels | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy |
| Wind speed (mph) | Feels | |
|---|---|---|
| 1 | 14 | breezy |
| 2 | 14 | breezy |
| 3 | 14 | breezy |
| 4 | 14 | breezy |
| 5 | 14 | breezy |
| 6 | 14 | breezy |
| 7 | 14 | breezy |
| 8 | 14 | breezy |
| 9 | 14 | breezy |
| 10 | 14 | breezy |
| 11 | 14 | breezy |
| 12 | 14 | breezy |
| 13 | 14 | breezy |
| 14 | 14 | breezy |
| 15 | 14 | breezy |
| 16 | 14 | breezy |
| 17 | 14 | breezy |
| 18 | 14 | breezy |
| 19 | 14 | breezy |
| 20 | 14 | breezy |
| 21 | 14 | breezy |
| 22 | 14 | breezy |
| 23 | 14 | breezy |
| 24 | 13 | breezy |
| 25 | 13 | breezy |
| 26 | 13 | breezy |
| 27 | 13 | breezy |
| 28 | 13 | breezy |
| 29 | 13 | breezy |
| 30 | 13 | breezy |
| 31 | 13 | breezy |
Sunrise & sunset in March
Daylight runs from about 11 h 30 min at the start of March to 12 h 12 min by month's end. The lit band spans sunrise to sunset each day.
Days grow by about 42 minutes over March. Sunrise moves from 6:57 AM to 6:26 AM, and sunset from 6:24 PM to 6:38 PM.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 11.5 | 11.5 | 11.5 | 11.5 | 11.6 | 11.6 | 11.6 | 11.6 | 11.7 | 11.7 | 11.7 | 11.7 | 11.7 | 11.8 | 11.8 | 11.8 | 11.8 | 11.9 | 11.9 | 11.9 | 11.9 | 12.0 | 12.0 | 12.0 | 12.0 | 12.1 | 12.1 | 12.1 | 12.1 | 12.2 | 12.2 |
| Sunrise (AM) | 6:57 | 6:56 | 6:55 | 6:54 | 6:53 | 6:52 | 6:51 | 6:50 | 6:49 | 6:48 | 6:47 | 6:46 | 6:45 | 6:44 | 6:43 | 6:42 | 6:41 | 6:40 | 6:39 | 6:38 | 6:37 | 6:36 | 6:35 | 6:34 | 6:33 | 6:32 | 6:31 | 6:30 | 6:29 | 6:27 | 6:26 |
| Sunset (PM) | 6:24 | 6:25 | 6:25 | 6:26 | 6:26 | 6:27 | 6:27 | 6:28 | 6:28 | 6:29 | 6:29 | 6:30 | 6:30 | 6:31 | 6:31 | 6:31 | 6:32 | 6:32 | 6:33 | 6:33 | 6:34 | 6:34 | 6:34 | 6:35 | 6:35 | 6:36 | 6:36 | 6:37 | 6:37 | 6:37 | 6:38 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| 1 | 11.5 | 6:57 | 6:24 |
| 2 | 11.5 | 6:56 | 6:25 |
| 3 | 11.5 | 6:55 | 6:25 |
| 4 | 11.5 | 6:54 | 6:26 |
| 5 | 11.6 | 6:53 | 6:26 |
| 6 | 11.6 | 6:52 | 6:27 |
| 7 | 11.6 | 6:51 | 6:27 |
| 8 | 11.6 | 6:50 | 6:28 |
| 9 | 11.7 | 6:49 | 6:28 |
| 10 | 11.7 | 6:48 | 6:29 |
| 11 | 11.7 | 6:47 | 6:29 |
| 12 | 11.7 | 6:46 | 6:30 |
| 13 | 11.7 | 6:45 | 6:30 |
| 14 | 11.8 | 6:44 | 6:31 |
| 15 | 11.8 | 6:43 | 6:31 |
| 16 | 11.8 | 6:42 | 6:31 |
| 17 | 11.8 | 6:41 | 6:32 |
| 18 | 11.9 | 6:40 | 6:32 |
| 19 | 11.9 | 6:39 | 6:33 |
| 20 | 11.9 | 6:38 | 6:33 |
| 21 | 11.9 | 6:37 | 6:34 |
| 22 | 12.0 | 6:36 | 6:34 |
| 23 | 12.0 | 6:35 | 6:34 |
| 24 | 12.0 | 6:34 | 6:35 |
| 25 | 12.0 | 6:33 | 6:35 |
| 26 | 12.1 | 6:32 | 6:36 |
| 27 | 12.1 | 6:31 | 6:36 |
| 28 | 12.1 | 6:30 | 6:37 |
| 29 | 12.1 | 6:29 | 6:37 |
| 30 | 12.2 | 6:27 | 6:37 |
| 31 | 12.2 | 6:26 | 6:38 |
Solar energy in March
Average shortwave solar energy reaching the ground each day in March, about 5.93 kWh/m².
For context, solar energy here swings from a low near 3.66 kWh/m² to a high of 6.9 kWh/m² in May across the year — March's 5.93 kWh/m² falls in the middle.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 5.3 | 5.4 | 5.4 | 5.5 | 5.5 | 5.5 | 5.6 | 5.6 | 5.7 | 5.7 | 5.7 | 5.8 | 5.8 | 5.8 | 5.9 | 5.9 | 6.0 | 6.0 | 6.0 | 6.1 | 6.1 | 6.2 | 6.2 | 6.2 | 6.3 | 6.3 | 6.3 | 6.4 | 6.4 | 6.4 | 6.5 |
| Level | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| 1 | 5.3 | Bright |
| 2 | 5.4 | Bright |
| 3 | 5.4 | Bright |
| 4 | 5.5 | Bright |
| 5 | 5.5 | Bright |
| 6 | 5.5 | Bright |
| 7 | 5.6 | Bright |
| 8 | 5.6 | Bright |
| 9 | 5.7 | Bright |
| 10 | 5.7 | Bright |
| 11 | 5.7 | Bright |
| 12 | 5.8 | Bright |
| 13 | 5.8 | Bright |
| 14 | 5.8 | Bright |
| 15 | 5.9 | Bright |
| 16 | 5.9 | Bright |
| 17 | 6.0 | Bright |
| 18 | 6.0 | Intense |
| 19 | 6.0 | Intense |
| 20 | 6.1 | Intense |
| 21 | 6.1 | Intense |
| 22 | 6.2 | Intense |
| 23 | 6.2 | Intense |
| 24 | 6.2 | Intense |
| 25 | 6.3 | Intense |
| 26 | 6.3 | Intense |
| 27 | 6.3 | Intense |
| 28 | 6.4 | Intense |
| 29 | 6.4 | Intense |
| 30 | 6.4 | Intense |
| 31 | 6.5 | Intense |
Hazard calendar for Key West
None of Key West's seasonal hazards are active in March. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.
Key West sits in the Atlantic hurricane belt; the season peaks August–October.
Key West's rainy season runs May–October, when most of the year's rain falls.
Is March a good time to visit Key West?
Our two travel scores rate March for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).
March is one of the better times to visit Key West for general sightseeing. The water and warmth also suit a beach or pool day.
What to pack for Key West in March
From March's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In March, Key West sees daytime highs around 74°F and nights near 71°F. Worth packing: light clothes, sun protection and a windbreaker. About 4 days see rain.
Sea temperature near Key West in March
The nearest coast averages about 74°F in March — the other half of the beach question. The full-year curve and swim-comfort zones are below.
The sea offshore is warmest in August at about 86°F and coldest in February near 73°F.
The water stays above 68°F all year — warm enough for a swim any month.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°F) | 73 | 73 | 74 | 77 | 80 | 83 | 85 | 86 | 85 | 83 | 78 | 75 |
| Comfort | Refreshing | Refreshing | Refreshing | Warm | Warm | Tropical | Tropical | Tropical | Tropical | Tropical | Warm | Warm |
| Sea temperature (°F) | Comfort | |
|---|---|---|
| Jan | 73 | Refreshing |
| Feb | 73 | Refreshing |
| Mar | 74 | Refreshing |
| Apr | 77 | Warm |
| May | 80 | Warm |
| Jun | 83 | Tropical |
| Jul | 85 | Tropical |
| Aug | 86 | Tropical |
| Sep | 85 | Tropical |
| Oct | 83 | Tropical |
| Nov | 78 | Warm |
| Dec | 75 | Warm |
UV index in Key West in March
Clear-sky midday UV in March peaks around 10 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Key West peaks around July 18 at about 12 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 18 at about 5 (high).
The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 6 | 8 | 10 | 11 | 11 | 11 | 12 | 12 | 11 | 9 | 6 | 5 |
| Level | High | Very high | Very high | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Very high | High | High |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 6 | High |
| Feb | 8 | Very high |
| Mar | 10 | Very high |
| Apr | 11 | Extreme |
| May | 11 | Extreme |
| Jun | 11 | Extreme |
| Jul | 12 | Extreme |
| Aug | 12 | Extreme |
| Sep | 11 | Extreme |
| Oct | 9 | Very high |
| Nov | 6 | High |
| Dec | 5 | High |
Air quality in Key West in March
Average fine-particle pollution (PM2.5) through the year — so you can see where March falls, not just the annual average.
Air quality in Key West is worst in July — around 18 µg/m³ PM2.5 (moderate), about 4.1× the cleanest month (December, 4 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 5 | 5 | 6 | 8 | 9 | 15 | 18 | 16 | 10 | 7 | 5 | 4 |
| Level | Good | Good | Good | Good | Good | Moderate | Moderate | Moderate | Good | Good | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 5 | Good |
| Feb | 5 | Good |
| Mar | 6 | Good |
| Apr | 8 | Good |
| May | 9 | Good |
| Jun | 15 | Moderate |
| Jul | 18 | Moderate |
| Aug | 16 | Moderate |
| Sep | 10 | Good |
| Oct | 7 | Good |
| Nov | 5 | Good |
| Dec | 4 | Good |
Where is Key West?
Key West sits at 24.6°N, 81.8°W, 3 ft above sea level, in United States. The nearest listed city is Marco Island, 96 mi away.
Topography around Key West
How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Key West.
Within 2 miles, the terrain around Key West has only modest variations in elevation — a maximum elevation change of 39 ft around an average of 3 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 75 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 52 ft.
The land around Key West is covered by water (64%) and artificial surfaces (26%) within 2 miles, water (95%) within 10 miles, and water (98%) within 50 miles.
United States travel facts
- Power plugs
- Type A / B
- 120 V · 60 Hz
- Prices
- ≈ 100% of US
- price level, 2025
- GDP per capita
- $90,027
- 2025
- Happiness
- 6.8 / 10
- World Happiness, 2025
- Safe drinking water
- 98%
- of population, 2024
- Homicide rate
- 5.8
- per 100k, 2023
- Road deaths
- 12.7
- per 100k/yr, 2019
- Income group
- High
- World Bank
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Key West (24.5552°, -81.7816°, elevation 3 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).