FLORIDA · WARM MINERAL SPRINGS · DECEMBER
December is the month the air finally drops well below the water. The spring runs at the temperature it ran in August: a U.S. Geological Survey gauge read 84.6°F (29.2°C) on September 11, 2026, and it reads close to that every day of the year. What changes is the air above it, and in December that air averages a high of 75.2°F and a low of 55.2°F.
So the question this date answers is not whether you can swim. It is what you wear at dawn, how much of the month is wet, how little daylight you get for the drive, and whether the holiday weeks are worth dodging. Three rain days, 10 hours 29 minutes of light on the 15th, and one Christmas week: that is the shape of a December trip here.
THE MONTH AT A GLANCE · WARM MINERAL SPRINGS · DECEMBER
December gives you the year’s widest gap between warm water and cool air, with short daylight and one holiday week to plan around.
AVG HIGH 75.2°F · AVG LOW 55.2°F · 2.33 IN OF RAIN · 10H 29M OF DAYLIGHT ON DEC 15
Go for: a soak in 84.6°F water on a morning that starts near 55°F, afternoons that still reach 75.2°F, and a month with only 3.0 days of measurable rain.
Think twice before: booking the Christmas and New Year stretch, and before counting on a fee or an opening hour we could not verify.
Air: NOAA NCEI 1991-2020, station USW00012871 · Water: USGS gauge 02299260 · Light: sunrise-sunset.org · full sources at the end
On this page
- December weather in one line75.2°F days, 55.2°F nights, 3.0 rain days
- Is the water warm enough to swim?84.6°F at the vent, against 55°F dawn air
- Crowds, lodging tax and what we could not priceThe holiday week and the missing numbers
- Things to do around the spring in DecemberThe vent, the gauge and the manatee question
- A two-day plan built on 10h 29m of lightDay one and day two, hour by hour
- December, November or January?How the three months compare
- Is December worth the trip?Our verdict, and who should shift
Everything below is dated to December. For the spring itself in any month, start at our Warm Mineral Springs guide, and for the statewide calendar see when to visit Florida.
Warm Mineral Springs weather in December: average highs, lows and rain days
| December normal | Figure |
|---|---|
| Average high | 75.2°F |
| Average low | 55.2°F |
| Precipitation | 2.33 in |
| Days with 0.10 in or more | 3.0 |
| Days with 1.00 in or more | 0.6 |
| Nights at or below 32°F | 0.3 |
| Daylight on December 15 | 10h 29m |
| Water at the vent | 84.6°F (one reading, Sep 11, 2026) |
The normals here come from NOAA’s National Centers for Environmental Information, 1991 to 2020, station USW00012871 at Sarasota Bradenton Airport, about 27 miles (44 km) from the spring. December averages a high of 75.2°F, a low of 55.2°F and 2.33 inches of rain. Those figures were read by an airport thermometer and they describe the air only. Nobody publishes a monthly air normal measured at the water’s edge, so treat the station as the closest honest proxy.
An average December records 3.0 days with at least 0.10 inch of rain, which works out to measurable rain roughly one day in ten. Only 0.6 day tops a full inch, so a genuine soaking turns up in about three Decembers out of five. On a two-night trip the odds favor you completely, and rain landing on somebody already in 84.6°F water costs nothing but the walk back to the parking lot.
Twenty degrees separate that average high from the average low, and December hands you both inside the same twelve hours. Pack for two climates in one bag: long pants and a hooded sweatshirt for the first hours, a t-shirt for two in the afternoon, and a second towel, since the first one will already be wet when you head back out to the car.
December 15 gives 10 hours 29 minutes of daylight, sunrise at 7:09 a.m. and sunset at 5:39 p.m. local time. The light goes soft around four and the last swimmers are drying off in dusk. Budget the drive home in the dark, or book the second night and stop watching the clock.
How warm is Warm Mineral Springs in December?
The air peaks at an average 75.2°F and bottoms at 55.2°F, a spread of exactly twenty degrees. The water sits above both: USGS station 02299260 read 84.6°F (29.2°C) on September 11, 2026, roughly 9 degrees warmer than a December afternoon and close to 29 degrees warmer than a December dawn. That 84.6°F is a single instantaneous reading rather than a monthly average, and the vent has no season, so December does not cool it.
In practice, you arrive dressed for late fall and swim in something closer to a heated pool. Morning calls for closed shoes, long pants and a layer you can shed in one motion. By two in the afternoon a t-shirt is enough on the bank, and the towel dries. Evening is the pinch: 5:39 p.m. sunset, a temperature already sliding toward 55°F, and wet hair.
Freezing mornings are rare but real. The station records 0.3 nights at or below 32°F in an average December, so about one December in three has a dawn at freezing 27 miles up the road. On that kind of morning, wear a robe from the car and leave the towel in the bag. The vent was pushing 8 cubic feet per second when the gauge was last read, and cold air does nothing to that.
How busy is Warm Mineral Springs in December? Crowds, prices and the demand peak
December sits inside Florida’s dry season, November through April, and its last week carries Christmas and New Year’s Day. We found no occupancy series and no monthly room-rate figures for this corner of the Gulf coast, so we crown no month cheap and no month expensive. Our statewide calendar explains why the peninsula fills between the holidays, and the cost guide sorts budgets by tier rather than by month.
We have no booking-window data either, so we will not invent a number of weeks. What the calendar does fix: December 25 and January 1 fall inside the school break, and lodging within an easy drive is the piece to settle first for that stretch. The first ten days of the month carry no national holiday at all. Our lodging guide covers the regional choices.
We could not verify the local lodging-tax rate, so we give no percentage. Ask any property to quote the all-in nightly total with taxes and fees before you confirm, because the gap between an advertised rate and a charged total is a real line in a December budget and it grows over the holiday week.
Spend the extra money on the car. The spring sits inland, the useful hours of a 10h 29m day are few, and a rental that lets you arrive early and leave after the light goes is worth more than an upgraded room, as our getting-around guide argues for the state in general. The second-best place for money is a second night, which gives your 3.0 rain days somewhere to land.
Things to do in Warm Mineral Springs in December
An afternoon at 75.2°F lets you dry off outdoors without hurrying, and that is the part January takes away: its average high is 2.7 degrees lower, at 72.5°F. November runs warmer still, 80.0°F, but the contrast between water and air is flatter then. December is the first month of the cool season where you feel the water as warm rather than merely pleasant.
The spring is the destination, and its numbers are unusually well documented for a small site: USGS station 02299260 measured 84.6°F and 8 cubic feet per second leaving the vent on September 11, 2026. That volume explains the clarity, since the water is replaced faster than it can cloud. Manatees move into Florida’s warm water in winter, and our manatee guide names the springs where encounters are organized. No count for this spring could be verified.
Across the three-month window the air swings 7.5 degrees, from 80.0°F in November down to 72.5°F in January, while the gauge stays near 84.6°F. That asymmetry is the whole December argument: the swim is identical to a July swim, the walk to it is not. Pair the soak with a Gulf beach afternoon if the sun cooperates, and Siesta Key is the obvious coastal stop.
On the practical side, we could not read an entrance fee or an opening hour from the official pages: floridastateparks.org answered our automated requests with a 403 on September 11, 2026. So no price and no schedule appear here, and we claim no free day exists. Call before you drive, and budget on the assumption that the water costs something.
Warm Mineral Springs in December: a two-day itinerary
Day one, leave late enough that the 55.2°F dawn is behind you and aim to be changed and in the water between ten and eleven, when the air has climbed toward the high sixties. Give the soak two hours, eat on the late side, then walk the perimeter while the sun still has height. Be back at the car by five, because sunset lands at 5:39 p.m. and the temperature falls with it.
Day two works better front-loaded: an early soak, a dry-off in the strongest part of the afternoon, then the drive to the coast. If the day is one of the month’s 3.0 wet ones, keep the swim and skip the beach, since rain on a swimmer changes nothing. If it is the 0.6 day that tops an inch, move the water to the morning gap and spend the afternoon driving.
Warm Mineral Springs in December vs November and January
| Month | Average high | Average low | Precipitation | Days with 0.10 in+ |
|---|---|---|---|---|
| November | 80.0°F | 60.1°F | 1.81 in | 2.5 |
| December | 75.2°F | 55.2°F | 2.33 in | 3.0 |
| January | 72.5°F | 52.3°F | 2.79 in | 3.6 |
All three months come from the same NOAA 1991-2020 series at the same airport station, so the columns are comparable. November runs 4.8 degrees warmer by day and 4.9 warmer by night, on 1.81 inches of rain. January drops 2.7 degrees off the afternoon, 2.9 off the night, and adds 0.6 rain day. The water sat at 84.6°F when the gauge was last read and carries no monthly series at all, in any of the three.
Shift four weeks earlier and you buy warmer evenings and half an inch less rain, at the cost of a smaller gap between water and air. Shift four weeks later and you get the sharpest contrast of the winter, colder dawns and 3.6 rain days. Our November page and January page carry the full detail for each.
Is December a good time to visit Warm Mineral Springs?
Yes, if you want warm water without summer heat. A 75.2°F afternoon, 3.0 rain days and 84.6°F water make a very easy weekend. It works less well for anyone planning a long outdoor day either side of the swim: 10 hours 29 minutes of daylight is two and a half hours short of June, and a 5:39 p.m. sunset ends the afternoon while you are still in a towel.
If that clock bothers you more than the temperature, take November instead. It averages 80.0°F by day, 60.1°F at night and only 1.81 inches of rain, which makes the drying-off part far less urgent. Skip January if you dislike cold mornings: 52.3°F is the coldest average low of this three-month window, on 3.6 rain days.
What no other month gives is this combination: an average afternoon still at 75.2°F, nights cool enough at 55.2°F to make 84.6°F water feel genuinely hot, and a holiday week you can either use or avoid on purpose.
The last word
Book two nights, not one, and put the swim in the middle of the day rather than at the end of it. One more thing worth knowing before you drive down: Florida Statutes 373.802(5) defines Outstanding Florida Springs as every historic first-magnitude spring plus six more named by hand in the law itself. Which list this vent falls under, we could not confirm. The 8 cubic feet per second leaving it in September will be leaving it in December all the same.
Sources & data for this guide
- December normals, rain days and freeze nights · NOAA NCEI monthly normals 1991-2020, station USW00012871, Sarasota Bradenton AP, about 27 miles from the spring · checked Sep 24, 2026
- November and January normals · same NOAA NCEI 1991-2020 series, same station · checked Sep 24, 2026
- Daylight, sunrise and sunset for December 15 · sunrise-sunset.org, converted to local time · checked Sep 24, 2026
- Water temperature 84.6°F and discharge of 8 cubic feet per second · USGS National Water Information System, station 02299260, instantaneous reading · checked Sep 24, 2026
- Definition of an Outstanding Florida Spring · Florida Statutes 373.802(5), leg.state.fl.us · checked Sep 24, 2026
- Entrance fee, opening hours and manatee presence: floridastateparks.org returned 403 to our automated reads and the state wildlife pages render client-side, so we publish no price, no schedule and no animal count · checked Sep 24, 2026
To plan your stay
- Best Time to Visit Warm Mineral Springs: Month-by-Month Highs, Rain Days and the Quiet Weeks
- Warm Mineral Springs in January: Weather, Crowds and the 84.6°F Water
- Warm Mineral Springs in November: Weather, Water Temperature and What the Month Costs You
- Warm Mineral Springs in February: Weather, Crowds and 84.6°F Water