West Palm Beach, FL rainwater: 49,079 gallons off a roof
Rainwater from a roof in West Palm Beach, FL
49,079gallons a year
That is a 1,500 sq ft asphalt roof under West Palm Beach, FL's normal 61.7 inches of rain, about 795 gallons for every inch that falls.
In West Palm 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 West Palm Beach Intl Ap station (4.5 mi away). West Palm Beach, FL ranks 56th wettest of the 173 cities covered in Florida.
Month by month in West Palm Beach
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 3.47 | 2,758 | |
| Feb | 2.63 | 2,090 | |
| Mar | 3.31 | 2,631 | |
| Apr | 3.68 | 2,925 | 84 |
| May | 4.91 | 3,902 | |
| Jun | 8.48 | 6,740 | |
| Jul | 5.63 | 4,475 | |
| Aug | 8.68 | 6,899 | |
| Sep | 7.96 | 6,327 | |
| Oct | 5.90 | 4,689 | |
| Nov | 3.62 | 2,877 | |
| Dec | 3.48 | 2,766 |
Aug is the wettest month (8.68 in, 6,899 gal off the roof); Feb the driest (2.63 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 West Palm Beach?
Best fit: one 55-gallon barrel, which delivers about 70 gallons to the garden in a normal year (83.8% of its need).
Before you buy, a 55-gallon barrel with a downspout diverter is the whole job. Check that the overflow points away from your foundation, because most of West Palm Beach's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 70 | 47,720 |
| 110 gal | 70 | 47,720 |
| 165 gal | 70 | 47,720 |
| 275 gal | 70 | 47,720 |
| 550 gal | 70 | 47,720 |
| 1,000 gal | 70 | 47,720 |
| 1,500 gal | 70 | 47,720 |
| 2,500 gal | 70 | 47,720 |
| 5,000 gal | 70 | 47,720 |
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