March in Naples

NCEI's daily normals for Naples Municipal Airport put the daily normal minimum at 59.9 F on March 6 and 60.0 F on March 7, the point where it climbs back to 60 F after a stretch of 89 dated records in NCEI's 366-day series, February 29 among them, that began December 9. It keeps rising through the month, reaching 62.7 F by March 31.

The airport still counts, on average, 12.4 March nights at or below 60 F, 2.3 at or below 50 F and 0.1 at or below 40 F, with a 0.0 percent probability of at least one night at or below 36 F or at or below 32 F; each count and probability sits at or below February's. The coldest reading in the year's table, and the freeze and frost definitions behind it, belong to January in Naples; March reads only its own numbers against them.

Those readings sit beside Seal 'n Lock's own lines for Super-Wet-Look: best results between 60 F and 90 F, and "Do not apply if surface or ambient temperature is below 50°F." Every March daily normal in NCEI's series, 59.5 F to 62.7 F at night and 78.7 F to 81.2 F by day, sits inside the 40 F to 95 F day-and-night window SEK-Surebond's TB17 gives as its typical case and inside Techniseal's 50 F to 85 F one. That is a comparison of airport air normals with makers' ranges, drawn by this page and by no maker; a smoothed average reaching 60 F is not a date the nights actually warm up, and which nights suit a sealer is the label's call, read against that night's forecast. Sealing pavers in a Naples winter reads the same three makers against December's, January's and February's own normal lows.

March's own four normals, 1.88 inches of rain, a 70.3 F average, a 79.7 F normal high and a 60.9 F normal low, sit between February's and April's, above February's by 0.48 inch of rain and by 2.8, 2.5 and 3.0 F. NCEI counts 4.4 provisional days with at least 0.01 inch and 2.1 with at least 0.10 inch, against February's 4.2 and 2.1.

The month's quartiles read 0.34, 1.39 and 2.78 inches, first, second and third, of its nonzero monthly totals. That 0.34-inch first quartile is the lowest of the twelve months, and the 2.44-inch span between it and the third quartile is the widest of any month from November through March, against February's 0.92-inch span, the narrowest of the twelve.

The daily chance of at least 0.01 inch rises through March, from a provisional 13.8 percent on the 1st to 16.5 percent on the 31st, the highest daily figure in NCEI's December-through-March series for the airport, and NCEI's month-to-date normal puts about 46 percent of the month's rain in the books by the 15th, an average split, not a forecast.

NWS Miami's fog page describes advection fog, warm moist air off the Gulf moving over a cooler land surface, as occasional during spring while the land is still influenced by periodic cold fronts, and often responsible for fog along the southwest coast of Florida. The definitions January in Naples sets out for fog and dew are not repeated here.

Whether a foggy March morning leaves a paver damp is not something any source read for this page measures. The National Weather Service defines fog as water droplets suspended in the air, not as moisture on a surface, and ICPI's Tech Spec 5 says of most sealers to "allow at least 24 hours without moisture or surface dampness before application." That condition is read off the surface itself, not off the morning's forecast.

In the same release where a UF/IFAS Extension Hillsborough County agent puts the height of pollen season at March and April, UF/IFAS also gives South Florida generally a wider February-to-May peak; no Naples or Southwest Florida pollen date turned up in the UF/IFAS pages read for this page. The calendar itself lives at pollen season, and what the dust does to glass at windows gone yellow in spring and pollen on a pane.

The South Florida Water Management District's 2026 environmental report puts the time when freshwater heads in the aquifer are lowest at March 1 to May 31, the window it names for sampling its saltwater-interface wells, inside the district's own dry season of November through May, and says groundwater levels at key sites are evaluated weekly as indicators of potential water shortages.

A separate NWS Miami study, reading Miami International Airport records from 1956 through 1997, ties the rains that open the summer season to an end of what it calls "the late winter dryness, and the all-too-frequent water-use restrictions" of that period and place, a description of that record, not a statement about the present. No district document read for this page says a shortage is declared most often in spring or in any other named season. Whether a shortage is in force on a given day is the district's own dated order, read with its posted status at water shortage phase and a water shortage warning and a roof wash; none of it is repeated here.