WASHINGTON — For those in the eastern half of the U.S., 2018 has been an exceptionally wet year. More than a dozen locations have recorded their wettest year on record, but we still have more than a week to go in the year which will include another round of very heavy rain. Heavy precipitation seemed to be an almost weekly occurrence in 2018, and added to that was a couple of soaking tropical systems which helped to quickly propel 2018 into the record books.
The most exceptional rainfall of the year has been in the eastern Carolinas. Wilmington, N.C. (as of Dec. 19) has recorded 100.14 inches of rain for the year. That’s nearly double their annual average of 57.61 inches. A decent chunk of the total rainfall for 2018 came in just three days with Hurricane Florence. Florence dropped 23.02 inches of rain on Wilmington in mid-September.
The rain isn’t over yet, as another 1-3 inches of rain is expected across a large swath of the eastern third of the nation between Dec. 20 and 21. A vigorous storm system will pump moisture from the Gulf of Mexico up along the East Coast causing a flooding concern from the Southeast to the Northeast. The storm will also bring severe thunderstorms to the Southeast with a few tornadoes possible, especially across the Florida peninsula and coastal Carolinas.
Evidence of 2018’s wetness is easy to see from a comparison of the U.S. Drought Monitor map from the most recent release (Dec. 18) compared to the same time last year (Dec. 19, 2017). Drought has been nearly eradicated in the eastern half of the U.S., including the dry spots across the Corn Belt.
Another thing you will notice from the drought monitor map comparison between this year and last year is the growth of drought in the western U.S. where 2018 year-to-date has been the driest in at least three years. However, a recent surge of strong Pacific storm systems in the Pacific Northwest should help to start knocking down some of the drought conditions in the region.
As we bid adieu to a soggy 2018, the next big weather story will be the Polar Vortex. The Polar Vortex became part of the media vernacular back in the winter of 2013-2014 when a displacement of the Polar Vortex caused a significant outbreak of cold, snowy, and icy weather.
Current model projections indicate that we’re in for another Polar Vortex disruption that could bring a very cold period of weather from mid-January to March. If the Polar Vortex is displaced, as several computer forecasting models predict, over southeastern Canada and the Great Lakes this would bring cold temperatures and increased threats of snow fall across the central and eastern U.S. The Polar Vortex event of 2014 brought unusually cold weather as far south as Tampa, Fla. Although it’s too early to tell exactly where and how far south the Polar Vortex will be displaced, there could be potential impacts to fruit growers in the South, especially for any crops ripening in February.
An additional concern with the potential Polar Vortex displacement would be a delay in planting. Combine cold weather with above normal soil moisture and that could be a recipe for a challenging start to the planting season in 2019.
For more WeatherTrends360, click here.