The hits keep coming. Hurricane Harvey left destruction in its wake, and now, Hurricane Irma has Florida in its sights.

It's been five years since Hurricane Sandy, nine years since Ike and twelve years since Katrina. As with all major weather events, personal tragedy, pain, suffering, and loss are left in their wake. We have prayed, and continue to pray, for those affected. But at the same time, in our job as economists we look toward rebuilding and economic restoration. This is where investors often make two different mistakes about how these massive weather events will affect the economy and markets.

Some might think that, as did Nouriel Roubini after Katrina, the damage itself will cause a recession. Others take the opposite tack and think rebuilding efforts might actually help the economy. Neither are correct. By themselves, the storms will not push the economy off its Plow Horse path.

In the face of disasters we should all be thankful for the (mostly) free markets that help the U.S. respond. These markets allow accumulated wealth and know-how to focus on recovery. The losses will never be fully replaced, but the sheer size and flexibility of the U.S.'s capitalist system allows resources to be shifted and directed toward recovery. The price system makes this happen. While some think no profit should be made from a disaster, it is those profits which allow overall "economic" recovery to occur in relatively quick order.

Some estimate that damage from Harvey could be close to the $108 billion estimate for Katrina (2005), certainly above the $75 billion cost of Hurricane Sandy (2012).

Neither of these previous storms caused a recession, and at the same time, the data show no real acceleration in growth either. Real GDP grew 4.9% at an annual rate in the first quarter of 2006 after Katrina, but never accelerated above 3% in the first two quarters after Sandy. For six and nine month periods before and after these storms, growth rates were similar. In other words, it's hard to separate the impact of Katrina or Sandy from normal statistical noise. The U.S. grew over 4% annualized in Q1 2005 and in Q3 2014, with no major weather impact.

But even if the bump in real GDP growth in the first quarter of 2006 was due to Katrina, that doesn't mean it was good news. It would be what Henry Hazlitt in his book "Economics in One Lesson" called the "fallacy of the broken window" – which we recommend all investors read.