Callaway, FL rainwater: 54,881 gallons off a roof
Callaway, FL: gallons off the roof each year
54,881gallons a year
That is a 1,500 sq ft asphalt roof under Callaway, FL's normal 69.1 inches of rain, about 795 gallons for every inch that falls.
In Callaway, 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 Panama City 6.9 Ese station (1.2 mi away). Callaway, FL ranks 7th wettest of the 173 cities covered in Florida.
Month by month in Callaway
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 5.89 | 4,681 | |
| Feb | 4.94 | 3,926 | |
| Mar | 5.09 | 4,046 | |
| Apr | 4.59 | 3,648 | |
| May | 3.63 | 2,885 | 90 |
| Jun | 5.34 | 4,244 | |
| Jul | 7.11 | 5,651 | |
| Aug | 14.66 | 11,652 | |
| Sep | 5.33 | 4,236 | |
| Oct | 3.49 | 2,774 | 107 |
| Nov | 4.25 | 3,378 | |
| Dec | 4.73 | 3,759 |
Aug is the wettest month (14.66 in, 11,652 gal off the roof); Oct the driest (3.49 in). Garden shortfall is what a 200 sq ft vegetable bed needs beyond the rain that lands on it, April to October.
What size rain barrel for Callaway
Best fit: one 55-gallon barrel, which delivers about 172 gallons to the garden in a normal year (87.3% 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 Callaway's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 172 | 53,540 |
| 110 gal | 172 | 53,540 |
| 165 gal | 172 | 53,540 |
| 275 gal | 172 | 53,540 |
| 550 gal | 172 | 53,540 |
| 1,000 gal | 172 | 53,540 |
| 1,500 gal | 172 | 53,540 |
| 2,500 gal | 172 | 53,540 |
| 5,000 gal | 172 | 53,540 |
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