Cooler weather this week
Published 7:00 am Tuesday, October 24, 2017
By Skip Rigney
We are deep into the autumn season as a parade of three cool fronts pass through the region this week.
In contrast to the monotony of summer, when there is very little change in the weather map from day-to-day, the deeper into the fall season we go, the more frequently weather systems move through the Deep South.
On Sunday the week’s first cool front stretching from Wisconsin down to the Gulf moved from west to east across the Mississippi Valley headed toward the East Coast.
Several rounds of showers and thunderstorms were kicked off in the unstable air ahead of the front, starting early Sunday morning in Pearl River County. The heaviest rain ended by mid-afternoon Sunday.
Rain totals with Sunday’s front varied significantly across the county. Most locations received one to two inches, but a few spots in extreme southeastern Pearl River County saw over three inches.
The cooler, drier air mass behind Sunday’s front has provided us pleasant fall weather Monday and today. After some post-frontal low clouds Monday morning, skies cleared. Monday’s early morning temperatures were in the upper 50s, and this morning’s were forecast to be in the upper 40s. High temperatures both Monday and Tuesday were forecast to be in the 70s.
Meanwhile, our second cool front of the week was in Kansas on Monday morning moving rapidly southeastward toward the Gulf Coast. This cool front should pass through south Mississippi sometime today.
Because the week’s first cool front swept most of the moisture out of the area, forecasters expect few if any clouds and certainly no rain with today’s moisture-starved front.
The main signs of the frontal passage today will be an increase in northerly wind speeds and a further drop in humidity.
The reinforcing shot of cool air behind the front will give us our coldest morning since March early Wednesday when the temperature is forecast to drop briefly into the upper 30s.
After a cold start on Wednesday, temperatures will slowly climb under bright, sunny skies into the upper 60s by mid-afternoon.
Thursday will begin cold, but otherwise should be a beautiful day with high pressure dominating the Gulf South. Temperatures are predicted to rise from the near 40 Thursday morning into the 70s that afternoon with plenty of sunshine.
Friday’s and Saturday’s weather will be unsettled as our third cold front of the week heads our way from the central United States. Our winds will veer around to a more southerly direction ahead of the front feeding moisture into the weather system and increasing our rain chances.
The timing of this final cold front of the week and its associated showers is still quite uncertain. Depending on which computer model turns out to be correct, showers could arrive in Pearl River County as early as Friday afternoon or as late as Saturday night. They could end as early as Saturday morning or as late as early Sunday morning.
Regardless, the models agree that the third cold front of the week will move through south Mississippi no later than Saturday night.
The Canadian air mass behind the front will likely make next Sunday and Monday our coolest days so far this fall with lows in the 30s and highs in the lower to mid 60s.