Fall arrives right on time for once

Published 7:49 pm Saturday, September 25, 2021

By Skip Rigney

A major pattern change has shifted our weather from summer to fall. Gone for the time being are the muggy humidities and frequent showers, replaced by cool mornings and sunny, mild afternoons.

For once, the day marked on the calendar as the first day of autumn (at least from the perspective of the earth’s position relative to the sun) coincided in Pearl River County with a switch to fall-like conditions thanks to a cool front that swept across the south-central and southeastern states on Wednesday.

Lows on Thursday and Friday mornings dipped into the lower to middle 50s in most locations in Pearl River County. Some spots which are susceptible to cool, dense air draining down into them probably cracked the 50 degree threshold. The last time it was this cool was back on April 26th.

Given that we have been experiencing one of our wettest years on record, the last several days have provided a welcome chance to dry out. Forecasters expect that it will be Tuesday before even a slight chance of showers returns to the forecast.

Two factors in the weather pattern will help ensure continued fair skies for the next several days. First, high pressure will dominate the lower levels of the atmosphere over the southeastern United States. Secondly, the winds at the high altitudes of the jet stream will continue to blow mostly from the west and northwest above the Gulf South. They will keep the high-altitude tropical moisture that has been common throughout the summer barricaded to our south over the Gulf of Mexico through mid-week.

If we make it through Tuesday with no rain, that will be seven consecutive dry days. Only six other periods during 2021 have been that dry: 12 days (March 3-14), 11 days (February 18-28, May 21-31), 9 days (January 12-20), 7 days (April 25 – May 1, August 4-10).

But, it doesn’t take too many years in the Gulf South to know that summer is the only season which comes and stays uninterrupted for months. All of our other seasons, including fall, are always advancing and retreating, trading places with the other nearest season.

So, yes, warm, more humid weather will be back by mid-week. At least for now, however, rain chances are forecast to remain relatively low, in the 20 to 40 percent range, from Tuesday through next weekend. That means some of us could have a stretch of ten days or more with no rain.

It is also too early to pack up the hurricane tracking charts. Hurricane Sam is advancing across the Atlantic. Thankfully, the consensus of the computer modeling is that Sam will recurve out into the central Atlantic far east of the United States. That’s a good thing because forecasters at the National Hurricane Center in Miami predict that Sam will become a very powerful hurricane as it crosses the warm waters of the Atlantic.

As of now there are no hints in the computer modeling of tropical mischief in the Gulf of Mexico over the next week. There are also no hints that we will see another southward surge of air as cool and dry as what’s over us now for at least another week to ten days. Enjoy the next few days.