To me, it is a big question. There was 7 billion dollars in damage done by hurricane/tropical storm Irene, according to the press. A lot of folks will earn wages or income repairing this damage. Perhaps some folks who have been unemployed, like those in the construction industry, will be working for awhile instead of barely surviving off unemployment or nothing if their unemployment has run out. Anytime money goes into circulation, it helps the economy. So rather than Irene having a negative effect on the economy, the storm may actually offer a small boost to the economy.
Incidentally, power and communication outages of this nature are generally short lived. Once the power goes back on, people will get back to normal in a nanosecond. I doubt this problem will have any long term or maybe even short term negative effect on the economy.
Here's the thing though-
What $ do people use to repair their roofs? Federal tax dollars in the form of FEMA money.
And Jeez, people will MILK that shit. When I lived in the trailer park during Hurricane charlie (6 years ago?) I remember everyone on my block - dealing with small panels broken on windows or branch damage - everyone got $5,500 FEMA checks - AND they got free trailers for a year if they wanted them, then they were allowed to BUY them for $2k if they wanted. It was a jackpot for ppl with shitty places.
Plus your theory forgets the lost GDP... entire chunks of some states are out of business for weeks or months.... they aren't paying taxes when they're not working. Entire infrastrctures need rebuilt. More tax dolalrs. How many insurance companies will go belly up? Crops destroyed for decades. FL lost tourism and snowbirds.
Finally, if you still feel I'm full of shit... Let's look at history.
Hurricane Katrina cost the economy more than $125 billion, delivered $81 billion in property damage, and left 1,836 people dead.