RoofRainYield

Amarillo, TX rainwater: 15,626 gallons off a roof

How much rain a roof in Amarillo, TX collects

15,626gallons a year

That is a 1,500 sq ft asphalt roof under Amarillo, TX's normal 19.7 inches of rain, about 795 gallons for every inch that falls.

In Amarillo, TX 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 Amarillo station (7.2 mi away). Amarillo, TX ranks 238th wettest of the 252 cities covered in Texas.

Month by month in Amarillo

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan0.71564
Feb0.53421
Mar1.271,009
Apr1.451,152362
May2.271,804259
Jun2.852,265187
Jul2.822,241191
Aug2.862,273186
Sep1.691,343332
Oct1.751,391324
Nov0.75596
Dec0.71564

Aug is the wettest month (2.86 in, 2,273 gal off the roof); Feb the driest (0.53 in). Garden shortfall is what a 200 sq ft vegetable bed needs beyond the rain that lands on it, April to October.

Which tank size is worth it in Amarillo

Best fit: 2 linked 55-gallon barrels, which delivers about 1,620 gallons to the garden in a normal year (88.0% of its need).

If you buy one, a 55-gallon barrel with a downspout diverter is the whole job. Check that the overflow points away from your foundation, because most of Amarillo's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal1,25213,804
110 gal1,62013,436
165 gal1,62013,436
275 gal1,62013,436
550 gal1,62013,436
1,000 gal1,62013,436
1,500 gal1,62013,436
2,500 gal1,62013,436
5,000 gal1,62013,436

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 Texas?

Rainwater harvesting is legal and encouraged; no state storage cap. HOAs may not adopt new covenants banning rainwater harvesting installations but may require screening. Local taxing units may exempt property with water conservation initiatives from property tax (Tax Code 11.32).

Checked against the current source on 2026-11-06. Source