Hurricane Isaac is maintaining its power and tremendous rainmaking. This is a general estimate from the Advanced Hydrologic Prediction Service of the rainfall over the last few days.
Those areas in red are where 10-20 inches of rain has fallen. Look at some of the amounts to our WeatherBug schools we tapped into.
But how much is this really? Well let's have a little fun with math, even with a terrible storm such as Isaac. I estimate that for the Gulf region (Louisiana, Mississippi, Alabama) and now Arkansas, about 100,000 square miles have been getting Isaac's rains.
A conservative estimate is an average rain (so far and counting) of 4 inches of rain. Every inch of rain over 1 square mile dumps over 17 MILLION GALLONS of WATER on the ground. So 4X17X1,000,000X100,000 gives us a rough idea. That comes out (check my math) to 7 TRILLION (7 followed by 12 zeros) Gallons of Water. How much is 7 TRILLION GALLONS? Imagine standing at Niagara Falls.
You would have to stand there every minute, every day for about 3 MONTHS to see 7 trillion gallons. Or 7 trillion gallons is also enough fresh water to give every man, woman and child on earth, 1 gallon of fresh water every day for about 3 years. Monster storm such as Isaac are tremendous engines that create enormous power and destruction and indeed incredible amounts of water. And Isaac is not doe yet. The winds are decreasing but the path is very likely to bring some rain our way before the Labor Day holiday weekend is over.
- Tropical Rainstorm Isaac is still at it and by the time it finally dies out early next week, may have generated 2-4 times as much water as it already has. Oh and I didn't even count the rain that Isaac dumped on the islands last week and Florida early this week!!