By Skip Rigney

The script has flipped. The unseasonable warmth of earlier this week is gone. Cooler-than-average temperatures are arriving, and it looks like they’ll stick around for at least the next week.

Daily high temperatures over the past 30 years in southeast Mississippi and southeast Louisiana for November 7th and 8th have averaged in the lower 70s. Here are some highs recorded around the region this past Monday and Tuesday, and they weren’t anywhere close to the average:

Picayune, 86 and 86; Poplarville, 86 and 84; Slidell, 89 and 90 (new records); Bogalusa, 90 and 89; New Orleans International Airport, 90 (new record) and 89 (tied record).

By Wednesday a little cooler and much drier air began blowing into the region, thanks in part to the circulation around Hurricane Nicole as it moved westward toward the Florida peninsula. That trend continued as Nicole curved northward from Florida into Georgia making Thursday and Friday days that local Chambers of Commerce would love to preserve in a bottle.

Early this morning (Saturday) a strong cold front moved across the central Gulf Coast and offshore into the Gulf of Mexico. As high pressure builds in behind the front, brisk north winds will blow in the coldest air that we’ve experienced since our first significant cold snap of the season back on October 19-21.

Forecasters expect patchy frost tonight and Sunday night with low temperatures in the middle 30s, but a few of the colder locations in the county may dip close to freezing. The ridge of surface high pressure extending from Canada southward into the northern Gulf will keep our weather fair through the weekend.

By Monday, look to the sky, and you’ll see that a change is on the way. Clouds will be on the increase, and by Monday night showers are forecast to spread over the region.

Monday night’s rain will be thanks to a weather pattern that often affects us in late fall, winter, and early spring. Cold fronts that move offshore stall in the Gulf of Mexico. If a disturbance at the high altitudes of the jet stream moves across Texas or northern Mexico toward the Gulf, it causes a wave of low pressure to form along the frontal boundary in the lower portion of the atmosphere in the western Gulf.

That surface low pressure system is pushed northeastward, towards us, by the winds at higher altitudes, bringing with it moisture, rising motion, and a good chance of rain.

Perhaps you can meditate on the amazing complexity and connections of atmospheric dynamics if the pitter patter of rain wakes you up Monday night.