For comparison purposes, Katrina dumped 16 inches in the most heavily drenched areas. Hurricane Floyd, which was considered to have produced extremely heavy rainfall and caused heavy flooding in North Carolina in 1998, produced 19.06 inches (48 cm).
The two cyclones (including Cyclone Eline) that hit southern Africa in 2000 produced a two-month maximum rainfall of 1365 mm, or 53 inches, resulting in the catastrophic Mozambique floods of that year, but I want to emphasize that that's a two month total that includes two cyclones and a number of other heavy-rainfall weather events.
So I'm not exactly saying that I don't believe your 40-inches number, I'm just a little curious about who might have predicted it, because it seems a little high to me....
The flooding, especially combined with the electricity, is the real danger. That's where people often get killed during hurricanes. They get electrocuted, or they drive off the road (because they can't see it) and get trapped in their cars. My understanding is that Oman and Iran have their first-responders and militaries ready, and have evacuated the truly vulnerable areas (barrier islands and so on). And my sense is that they'll be able to handle it. WHEEEEEEEEEEEEEEEEEEEEE!
Perhaps they meant 40 cm?
That would be about 15 inches.
God know that the English system confounds communication with the rest of the world. And the Brits only complicate it. I enjoyed having a conversation with a friend who talked about some big guy they knew that must have been 15 stone. Now there's a measure that no one but our British friends (and the Irish) understand. And I'll give my consent to any government that does not deny a man a living wage-Billy Bragg