The Storm Over Houston Has Been Dropping a Month of Rain an Hour

Over 15 inches of rain fell on parts of Houston early Monday morning.
Severe Weather Texas
A rescue boat approaches Greens Bayou in Houston, Texas on April 18, 2016.Steve Gonzales/Houston Chronicle/AP

Well, it's floodin' down in Texas, and all the telephone lines are down. Or at least, busy with calls from relatives, friends, and journalists calling to find out exactly what happened, who is safe, and what has drowned in the city of Houston.

Late Sunday night and early Monday morning, a huge weather system dropped over 15 inches of rain on parts of Southeast Texas. In some places, water was falling at a rate of 4 inches per hour—Houston typically gets less than 4 inches in the entire month of April. This has flooded many of the bayous surrounding the city, submerged roads, and resulted in over 650 calls for rescue from residents.

According to Andrew Orrison, lead forecaster at NOAA's Weather Prediction Center, this rain is associated with the same system that has dropped up to 40 inches of snow on parts of the Rockies over the past few days. "This is a very large system, associated with a cold front moving very slowly," he says. That sluggishness comes from being detached from the westerly winds associated with the jet stream.

Orrison says these kind of detached, slow-moving storms are common in springtime, when the jet stream (which flows along more southern latitudes during the winter) moves into its more northern, summertime position. "If you are going to get a really slow moving upper atmospheric low pressure system, this is the time to have it," he says. "But what happened last night was pretty extreme."

The storm should start moving east in the next few days, but could bring more flash flooding to southeast Texas before it trudges completely away from the region. Meanwhile, the flood water keeps on rollin', makin' people there insane.