The Alabama Climate Report

Brought to you by the Office of the Alabama

Volume 7, Number 8 - May 2017

May certainly wasn't quiet. At least three significant storm systems knocked down trees and utility poles, blocking roads and causing power outages and flash floods in spots across the state while also causing some un-May-like cool temperatures.

Montgomery had its wettest May on record, with 12.74" of rain for the month. That included 8.15" just on May 20. The former record for May was 12.01" set in May 1978.

But Montgomery was unique in that respect. Mobile got more than 10" of rain in May, but that isn't close to the 15.08" May 1980 record. Likewise, Troy recorded 7.77" of rain in May, which was 1.8" short of the May 1976 record.

Several stations saw daily rainfall records broken, but for the month most of Alabama seemed to fall somewhere in the slightly wetter than normal to slightly drier than normal spectrum.

Those cool temperatures kept May's high temperatures on the cool side. Looking only at high temperatures, May 2017 was the 40th coolest May on record in Birmingham, the 29th coolest in Montgomery and the 20th coolest in Mobile. The average high temperature was cooler than normal in Huntsville. A couple of dozen daily records were broken statewide for the "lowest high temperature."

Despite the generally cool highs in May, the year to date has been generally warmer than normal. Through May, 2017 has been the second warmest start to a year in Birmingham and Mobile, is tied for the warmest start in Huntsville, and is the warmest first five months on record in Montgomery.

Warmer than normal temperatures aren't much of a hardship in January, February and March. If the trend continues into July, August and September, however, it could be a hot and sticky summer.

June is the official start of the hurricane season, although we've already had one named storm this year: Tropical storm Arlene back in April.

The official forecast is for a slightly better than normal chance of the more active than normal hurricane season this year. The chance that we will see an El Niño Pacific Ocean warming event (which typically suppresses Atlantic hurricane formation) form this summer is about 50/50. The expectation is that if an El Niño does form, it will probably be weak and have little impact on Atlantic hurricanes.

We are working on our 12th hurricane season since a major (category 3 or stronger) hurricane hit the continental U.S. That is far and away the longest major hurricane "drought" on record. If we have no faith in the hurricane forecast, plain old statistics and that regression to the norm thing would tend to say the longer we go without a major storm, the more likely it becomes that we will get one.

Which means this isn't a good time to neglect our hurricane preparations. There's never really a good time to neglect our severe weather prep. After more than a decade of relative quiet, however, human nature and putting things off can kick in. Not a good idea.

- John Christy