Warmth continues here as record cold invades U.S.
By Skip Rigney
Record-breaking cold is forecast to overspread the western two-thirds of the United States over the next few days but will not have enough eastward momentum to affect our weather. Temperatures in Pearl River County, and most of the southeastern U.S., will remain on the warm side of the late October averages through at least the middle of the upcoming week.
The forecast lows in the middle 60s are 10-15 degrees warmer-than-average. The forecast highs in the 80s are 5-10 degrees warmer than the historical averages for the last week in October. Along with the warm temperatures, we can expect rather high humidities.
In contrast, people from Montana all the way southward into the heart of Texas will think that winter has arrived a couple of months early.
Cold air and snow made its first incursion into the U.S. earlier this week. Most of Minnesota and the Dakotas picked up two to eight inches of snow, while some of the mountains in the northern Rockies were buried under a couple of feet of snow.
A second shot of even colder air is pouring across the Canadian border this weekend. Daily low temperature records will likely be broken at some stations in Montana, Wyoming, Colorado, and the Dakotas as temperatures plunge into the single digits and in some cases below zero.
Wintery weather seldom seen in October will spill as far south as Texas.
The area known as the Big Country in central Texas between Fort Worth and Abilene, which will be near 90 degrees Sunday, will plummet to near freezing Monday night, and could even see sleet or snow early this coming week.
A dome of high pressure will be strengthening over the southeastern U.S. over the next few days, slowing the cold front’s eastward progress through Louisiana to a snail’s pace on Monday and Tuesday, keeping us on the warm, humid side of the front.
The computer weather models predict that by Wednesday an intense low pressure system in the upper atmosphere will form over Texas and begin lumbering its way eastward, pushing the high pressure out of the way and allowing the cool front to finally pass through our area.
However, the models disagree about the timing of when the cool front arrives in south Mississippi. It could be as early as Wednesday, or as late as next Saturday.
Regardless of the timing, showers are likely to develop sometime between Wednesday and Friday as a strong rising motion on the eastern flank of the circulation around the low pressure system combines with the ample supply of heat energy and moisture ahead of the cold front.
It’s too early to forecast how many of these showers will become thunderstorms and if any of those may strengthen to severe levels, but it is a possibility.
By the time the front finally does stumble through south Mississippi, the very cold air that will be in Texas early in the week will have had time to warm up substantially.
Behind the front, our temperatures will merely fall back to near the late October historical averages of lows in the 50s and highs in the 70s.