Weather in Key West in March

Prime time. If you get to pick your dates, March is the one. Highs average 24 °C, lows 22.6 °C, and rain falls on 5 days — nothing in the month is working against you.

March ranks 3 of 12 in Key West. Only January scores clearly higher, and the difference is small enough to be settled by price rather than weather.

Rain falls on only 5 days, so an itinerary with no wet-weather fallback is a reasonable risk. Nothing specialised needed — this is the month you pack for the trip rather than for the weather.

What the averages hide

Averages flatten a month, and this one hides a few things: it never really gets hot: not one day in an average March reaches 30 °C; the day barely swings — 1.4 °C between the overnight low and the afternoon high. Across the twenty years measured, the hottest March day reached 27.2 °C and the coldest night fell to 15.7 °C, and the wettest single day dropped 39 mm — roughly 150% of the month's rain in one day.

This is the volatile part. March rainfall has ranged from 1 mm to 85 mm across the twenty years measured — a 84 mm spread around an average of 26 mm. The average is real but almost no individual March looks like it, so treat the figure as the middle of a wide range rather than a forecast.

Wind sits around 18.3 km/h — a steady breeze rather than a nuisance, and welcome on the warmer days, and humidity runs at 77%, high enough to notice on the warm days without dominating them.

How March sits in the year

Temperatures hold steady either side: 23.1 °C in February, 24 here, 25.5 in April. Nothing about the timing within the month matters much.

Daylight in March

12 hours of daylight, gaining 0.7 hours across the month. That is between Key West's extremes of 13.6 and 10.6 hours, so days are long enough not to constrain the plan.

Sea temperature

The sea sits at about 25.3 °C in March — warm enough to stay in as long as you like. The sea peaks at 29.9 °C in August and bottoms out at 24.9 °C — water lags the air by a month or two, which is why the best swimming often comes after the best weather.

How busy it gets

Peak season. Expect the highest prices of the year and to be booking well ahead.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

March in Key West versus nearby

If Key West is one option among several, the nearby comparison is worth making. Miami is close enough to be a coin toss — within a degree on temperature, 4 days more rain. Cape Coral is close enough to be a coin toss — within a degree on temperature, 2 days more rain.

So: March is effectively as good as it gets here — 0 points behind January, which is inside the margin where the weather stops being the deciding factor and price starts being it.

Every month in Key West

See all twelve months in Key West, or where else to go in March.