A Destructive Kind of Cunning

The dodgy behavior I saw with Harvey this afternoon ended with sunset, but there's no assurance it won't happen tomorrow too. I think Harvey was using Houston's afternoon heat to try and make itself much more compact and efficient. Had there been assisting factors, like the presence of an inland, upwind range of hills or mountains (something like you see in Australia), it might have even succeeded. There's almost a destructive kind of cunning about this storm.

The Harris County Flood Control District has a map on their website posting rainfall data for its gauges. Here is rainfall over the past week (which is a little longer than, and thus contains more, than the storm total). There are a few places with more than 40 inches - more than a meter - of rain in a week. These rainfall totals are highly-unusual, and perhaps record-breaking.

Insurers and the federal government have reason to revisit Houston-area flood risk assessment and adjust rates accordingly. According to an article in Slate:

"This is the third straight year that Houston has endured a devastating, once-in-a-lifetime flood. There were the Memorial Day floods in 2015 and the Tax Day floods in 2016. Together the storms killed 16 people and caused more than $1 billion in damage. More than a third of the properties that flooded in Houston’s 2015 Memorial Day floods were located outside the “hundred-year floodplain,” the zone in which FEMA requires homeowners with government-backed mortgages to elevate homes or buy flood insurance. Now with Harvey, Houston has been hit with six “hundred-year storms” since 1989."

And heavy rains continue in southeast Texas....