Record low drought since monitoring began 17 years ago
Thursday, May 4, 2017, 3:30 - Since drought monitoring began back in January of 2000, current values as of May 2, 2017 are the lowest in these 17 years and 5 months of recorded data. Current D1 to D4 (moderate to exceptional drought) average values are affecting 4.98 percent of the contiguous US. The previous record low set back in July 2010 was 7.7 percent.
One year ago, 33.89 percent of the contiguous US was experiencing some type of drought, with 14.56 percent in the moderate to exceptional drought category and 2.33 in an extreme drought alone. Today extreme drought affects only 0.13 percent of the countries surface and there is no exceptional drought in sight.
The most remarkable changes in the drought monitor values are those recorded in the west. A year ago 56.25 of the region was under some type of drought scenario, but today that value has shrunk to 12.83 percent. There are no longer signs of extreme or exceptional drought conditions, and only 2.72 percent exhibits a moderate to severe drought situation.
California benefited the most from the late Fall and Winter rains after five years of consecutive drought, today only about 8 percent of the state is experiencing some type of drought. The lingering El Niño of 2016 brought some relief to the state as had already happened during other strong El Niño years like back in 1982-83.
A favorable weather pattern with a record breaking number of Atmospheric Rivers during the 2016-17 winter months also delivered plenty of moisture into the western third of the US helping erase a large swath of drought values across many areas.
Normally a dozen Atmospheric Rivers hit the west coast on a given year, but this season, more than 30 have been detected. Moisture transported all the way from the western Pacific near southeast Asia has been a key ingredient to produce large amounts of rain and snow in many areas of the west although by this time of year we should be seeing fewer of these plumes of moisture flowing into California.
Spring rains benefit other drought stricken areas of the south and east
Over the past few weeks, a favorable atmospheric circulation pattern brought some relief in the drought situation to many areas of the south and east. An active jet stream has been driving storms across portions of the Central Plains and the Tennessee River Valley, areas which have been affected by moderate to extreme drought conditions throughout much of the Winter and Spring months. Two weeks ago 44.63 percent of the southeast region was experiencing drought, today that value has been cut down to 34.35.
Despite the good news for those fighting a prolonged drought in the southeast US, other nearby areas have not been so lucky as flood waters have produced extensive damage. A swath extending from the Central Plains, across the Mississippi River Valley all the way to the Eastern Seaboard, has experienced heavy rains and severe flooding over the past two weeks. Unfortunately, forecasts call for more intense precipitation by next week.
The longer term drought forecast anticipates that dry conditions during the rest of Spring into early Summer will persist in many areas of the southeast and could even increase as we get closer to summer.