What is a flash drought?

I spend some time looking over weather and climate research sites. Generally, there’s something interesting that captures my attention. These are things that I like to share with you. Recently, I came across the term “flash drought.” I had never heard this term before.

The National Weather Service’s (NWS) Climate Prediction Center defines a flash drought as “an event during which an area experiences degradation by two or more drought categories in a four-week period, based on the U.S. Drought Monitor.” Two or more categories in a month is really fast.

So, where did these flash droughts occur in 2019? Last year the majority of Texas was in drought for a long period of time. Quickly hit with a flash drought was the Southeast United States. Here is what happened according to the National Oceanic Atmospheric Administration (NOAA). “In Georgia, where over 7.5 million people are currently in drought areas, only 7 percent of the state was in drought at the beginning of September. By the end of the month, that number reached 62 percent of the state. Severe to Exceptional drought (categories D2-D4) went from 0 percent of Georgia at the start of the month to 28 percent by the end. The southeastern United States in general went from around 6% of the region in drought to 44% in less than a month, and from essentially 0% in severe to exceptional drought to nearly 14%.”

Let’s focus down even tighter to one state, Kentucky. No part of the state was in drought at the beginning of September 2019. By the end of September, 91% of the state was in drought. Areas in at least severe drought went from 0% on Sept. 17 to 58% by Oct. 1. Really drastic event, this flash drought.

The addition of more super computer power to create modeling of weather events will help predict more details like flash droughts. Currently, the United States and European weather services have some serious computing power to create modeling of weather forecasts. Some feel the European system may have the edge on forecast modeling. Earlier this year the National Oceanic and Atmospheric Administration (NOAA), the governmental body that oversees the National Weather Service (NWS) announced that it is tripling supercomputing capacity for weather and climate modeling over the next few years. Two new Cray Super Computers will be added to the system, bringing a total of 40 petaflops of computing power. The more petaflops you have, the more and quicker computing you can do, I guess. I’ll leave up to you to figure out what a petaflop is – likely faster than my desktop computer.

Let’s take a look at the past month’s weather statistics. All stats are from my home weather station. The high temperature for February was 59.9˚F and the low was 15.7˚F. Mean temperature was 35.1˚F. The all-time high was 61˚F in 1995, all-time low was -15˚F way back in 1950. The all-time mean is 32.7˚F. We were 2.4˚F above the all-time mean temperature. Precipitation came mostly as snowfall. I measured 7.2 inches of snowfall and a total of 0.76 inches of water — both rain and snow water equivalent. For those interested, Moses Mountain, as of this writing, has 36 inches of snow.

EarthSky.org provides this for our planet viewing pleasure: “In March 2020, Venus reaches a milestone in the west after sunset. Meanwhile, in the east before sunrise, Mars has a conjunction with Jupiter on March 20, and Saturn on March 31.”