The Alabama Climate Report

Brought to you by the Office of the Alabama
Climatologist

Volume 7, Number 5 - February 2017

For most of Alabama, it has been a long time since we saw a February this warm. If you look at the climate record, however, that's hardly surprising: With the exception of 1990 (and now 2017), the 13 warmest Februaries on record in Alabama all happened at least 55 years ago. (13 because there is a tie for 12th.)

The February just past is the warmest on the Southeast Regional Climate Center's 81-year climate record for both Huntsville and Montgomery. Huntsville's average temperature (53.1°) was more than a full degree Fahrenheit warmer than the second warmest February (1990 at 51.9°), while Montgomery's 59.4° was one tenth of a degree warmer than the previous warmest February in 1957.

It was also the second warmest February on record in both Mobile (61.4°) and Birmingham (55.4°).

It will be several days before the official statewide numbers come in, but early reports indicate February 2017 should slide easily into the state's top five warmest Februaries.

But what (if anything) does that mean in terms of forecasting for the coming spring?

Generally speaking, absolutely nothing.

There is no apparent correlation between a warm winter and the spring weather that follows. We are no more likely to get March snow after a warm February than we are after a cold one. Violent weather is typically the result of short-term weather systems, rather than those that linger for weeks or months at a time.

One effect of the warm dry month-and-a-half, however, is the way it warmed the soil and advanced the emergence of vegetation about three weeks ahead of schedule.

Two major consequences are (1) an increased vulnerability to freeze damage, and (2) the diversion of soil moisture from supporting stream flows to supporting plant growth. Indeed, we are seeing stream flows in some cases near all time lows in north Alabama. And a freeze in March is usually a good bet, especially in the north end of the state. Frost damage to plants and crops is much more likely when February or March is unusually warm. Remember April 2007 and the Easter Freeze after a very warm March?

Which brings us to March. While Alabama recorded two tornadoes in February and 21 in January (21!), March is generally considered the start of the four-month peak tornado season for the state.

While the April 2011 tornado outbreak remains fresh in our memories, the state's deadliest tornado event was the storm system that hit the Southeast on March 21-22, 1932. While tornadoes from that system were reported from Mississippi to South Carolina (and as far north as Illinois), Alabama was the hardest hit, with 268 deaths and another 1,849 reported injured.

Unfortunately, March pops up again and again in Alabama's tornado history: March 18, 1899, with 40 killed. March 21, 1913, with 27 killed. March 18, 1920, with 17 fatalities. March 27, 1932 — less than a week after the deadly outbreak — with six additional deaths. Palm Sunday 1994, with 22 fatalities. And so forth.

This past weekend was the tax holiday for emergency preparations, and that's a good thing. But whether you save eight or nine percent or not, now is a critical time for weather preparation and awareness. History and science give us all the warnings we need, but it means nothing if we don't make a plan and prepare for the worst.

- John Christy