Rains break dry spell, cool front on the way
Published 7:00 am Saturday, June 8, 2019
By Skip Rigney
After 15 days without rain, between 1.25 and 3.25 inches fell on Pearl River County from Wednesday afternoon through Friday morning, and forecasters expected more showers on Friday and Saturday.
Abundant moisture from the Gulf of Mexico began to be funneled north into Louisiana and Mississippi on Wednesday by a weak tropical disturbance in the western Gulf. A separate disturbance in the upper atmosphere was slowly moving eastward from north Texas and Oklahoma at the same time. The two systems have helped produce widespread rain over the past several days from the upper Texas coast through Louisiana and south Mississippi. The rain from these most recent systems will only aggravate the flooding situation in south Louisiana in the Atchafalaya Basin. However, the main reason for flooding there, as well as in the Mississippi Delta region north of Vicksburg is that waters have backed up from the Mississippi River, which has been very high since last fall.
The flooding in the lower Mississippi River Valley is not surprising given that the twelve months from May 2018 through April 2019 were the wettest on record for the lower 48 United States, including the entirety of the River’s watershed. That’s according to information disseminated last week by the National Center for Environmental Information, a division of the National Oceanic and Atmospheric Administration.
The River’s watershed covers much of the continental United States from the eastern slopes of the Rocky Mountains in the west, to Minnesota in the north, to the western slopes of the Appalachian Mountains in the east.
The same twelve month period in Pearl River County was wetter than normal, but certainly not the wettest on record. From May 2018 through April 2019 the Poplarville Experiment Station recorded 66 inches of rain, which is about five inches above average. A station just east of Picayune recorded 59 inches during the same period as reported to the Community Collaborative Rain, Hail, and Snow Network.
Thirty other May-April annual periods out of the 85 on record for Poplarville have been wetter than 2018-2019. The wettest of all just recently occurred when the Experiment Station received an incredible 95 inches of rain from May 2017 through April 2018.
The surface and upper low pressure systems that caused the recent rain have come together, and by Sunday the combined low is forecast to be to our east over Alabama. That will put us on the western side of the system with light winds from the north. Those winds will bring in drier air, but there will still be just enough humidity and instability around to give us a slight chance of showers on Sunday and Monday.Sunday a cool front is forecast to push southeastward out of the Great Plains. National Weather Service forecasters in Slidell think that by Monday night or Tuesday there is a good chance the front will pass across the Gulf Coast dropping our rain chances for the rest of the work week to slim or none.
Behind the front, afternoons will be in the upper 80s. Forecasters are predicting a nice, dry feel to the morning air on Wednesday through Friday with low temperatures in the middle to even lower 60s. Enjoy it. We may not see mornings that cool again until late August or September.