Since the start of fall in early-September, portions of the United States began to dry up due to a lack of water. The summer was harsh for portions of the Northern Plains and Northwest while there were only patches of abnormally dry conditions in the Southern Tier. As the season of fall progressed, however, many areas in the South weren’t receiving as much rain as they would typically receive, therefore getting them into abnormally dry conditions and eventually a moderate to severe to even extreme drought. Every new week as a new drought monitor update gets released, it shows a worsening to most of the drought affecting the nation because it’s been so dry relative to average. The animation below shows the comparison in drought conditions between September 5th, 2017 and the most recent map update on January 20th, 2018.
Again, the main reason for the worsening drought is the lack of water. The map below highlights the precipitation anomalies, which means how much precipitation fell compared to average. Notice how where the below average precipitation since October of 2017 correlates with where the drought is.
The map below shows our current state of drought across the Lower 48. Currently, 67.10% is in abnormally dry conditions or worse, 38.42% of the area is dealing with at least a moderate drought, 17.21% is experiencing at least a severe drought, and 1.72% is dealing with an extreme drought. Thankfully at this time, there are no areas in an exceptional drought, but based on the long-range outlook, which we discuss later in this article, we wouldn’t be surprised it develops.
Also, the drought in California is unfortunately beginning to worsen again. The ongoing La Niña, which is known for keeping the South dry, is not helping with the weather on the West Coast either. Rain in the Golden State and snow in the Sierra Nevada Mountains has been scarce this winter season following a record-water season during the winter of 2016-2017. The current snowpack in the Sierra on average is only 14% of normal. That is significantly low than where the mountains should be at this time.
Now if we look at the long-range pattern through the rest of winter and into the start of spring, the news is looking grim for the areas that are experiencing a drought. NOAA is anticipating the drought to continue or worsen across most areas currently experiencing a drought, although some relief is expected in portions of the Northern Plains and Carolinas. The big picture, however, is for the worsening drought to continue with more drought expected to develop across parts of the Southern Tier as the South stays dry while the North continues to deal with an active storm track.
The effects of this drought are already being felt. In the West, ranchers in Arizona are starting to haul water as their ponds dry up for their cattle. Some people’s wells are even drying up across the Southwest U.S. region. In California, the risk for wildfires are growing, and there’s already been a history this winter of huge wildfires, like the Thomas Fire which was the largest ever recored in the state. The drought hasn’t begun to affect most reservoirs in California yet, as most of them are measuring full or at normal values, but the future does not look good for these water bodies.
The South has also been terribly affected by this long-range drought as well. The Bristol Tri-Cities Airport station in Tennessee has received only 3.73 inches of precipitation since November 11th, 2017, which is the driest November 11-January 30 period on record. Also in Texas, the Amarillo International Airport has had 109 consecutive days with no measurable precipitation as of January 30th, edging out January 3th, 1957 whose dry run lasted 75 consecutive days. This drought has slowed the growth of wheat and pasture conditions have been poor. Several large brush fires have also been reported in parts of Texas and Oklahoma, promoting a burn ban across western Oklahoma.