Fernandina Beach, FL rainwater: 39,685 gallons off a roof
Rainwater from a roof in Fernandina Beach, FL
39,685gallons a year
That is a 1,500 sq ft asphalt roof under Fernandina Beach, FL's normal 49.9 inches of rain, about 795 gallons for every inch that falls.
In Fernandina Beach, FL a single barrel does most of the work. Storms come often enough that a small tank refills before it runs dry, and a bigger one would mostly sit full.
Rainfall: NOAA 1991-2020 climate normals, the Fernandina Beach station (0.6 mi away). Fernandina Beach, FL ranks 164th wettest of the 173 cities covered in Florida.
Month by month in Fernandina Beach
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 3.20 | 2,543 | |
| Feb | 3.13 | 2,488 | |
| Mar | 3.27 | 2,599 | |
| Apr | 3.03 | 2,408 | 165 |
| May | 2.68 | 2,130 | 208 |
| Jun | 6.12 | 4,864 | |
| Jul | 4.96 | 3,942 | |
| Aug | 6.39 | 5,079 | |
| Sep | 7.19 | 5,715 | |
| Oct | 4.97 | 3,950 | |
| Nov | 1.87 | 1,486 | |
| Dec | 3.12 | 2,480 |
Sep is the wettest month (7.19 in, 5,715 gal off the roof); Nov the driest (1.87 in). Garden shortfall is what a 200 sq ft vegetable bed needs beyond the rain that lands on it, April to October.
Barrel or cistern in Fernandina Beach?
Best fit: one 55-gallon barrel, which delivers about 318 gallons to the garden in a normal year (85.3% of its need).
If you set one up, a 55-gallon barrel with a downspout diverter is the whole job. Check that the overflow points away from your foundation, because most of Fernandina Beach's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 318 | 38,196 |
| 110 gal | 318 | 38,196 |
| 165 gal | 318 | 38,196 |
| 275 gal | 318 | 38,196 |
| 550 gal | 318 | 38,196 |
| 1,000 gal | 318 | 38,196 |
| 1,500 gal | 318 | 38,196 |
| 2,500 gal | 318 | 38,196 |
| 5,000 gal | 318 | 38,196 |
Simulated storm by storm through a normal year using the station's count of days with 0.1 in or more of rain each month.
Is rainwater collection legal in Florida?
Legal. Florida approves onsite non-potable use of rainwater for landscape irrigation, vehicle washing, filling pools and fountains and, in some local jurisdictions, toilet/urinal flushing (Florida Plumbing Code). No state storage cap or registration for non-potable collection.
Checked against the current source on 2026-11-06. Source