As it has for much of the past week, “air you can wear” lingers over the Southern US.

Ridging over the region lead to warm, moist air from the Gulf moving in for a bit of a summer preview. Not only did we have sticky days, but those afternoon pop-up storms were abundant. However, as Armando mentioned in his Saturday blog, the pattern is about to shift once again.

Ridging will remain firmly entrenched over the West. As this ridge amplifies further, troughing is favored to develop downstream over the Eastern US.

This works out to temperatures only slightly below average for the South – but somewhat more below average under the stronger trough over the Northeast. The biggest change the South will “feel” is the drier air moving in.

First, a brief break from the humidity moves in as a front passes through tomorrow. By the weekend, a stronger front will bring in some significantly drier air. Well, significantly drier for late May, at least.

The first front I mentioned, the one moving through on Tuesday, will bring a risk of severe weather to the Lower Ohio Valley, Tennessee Valley, and into the Mid-Atlantic.

Ahead of the front tomorrow, moisture in place combined with daytime heating under broken cloud cover/initially sunny skies will allow for a modest amount of CAPE to build. By the time aline of storms arrives in the TN/OH Valley region in the late afternoon and evening hours, they should have roughly 1000 to 2000 J/kg of CAPE to fuel them.

Further east in the Mid-Atlantic, pop-up style storms are possible ahead of the main line, which won’t roll through this region until the overnight hours.

As far as hazards go, damaging winds will be the primary threat. Some larger hail is possible. The tornado threat is very low, but not zero – mostly in the Mid-Atlantic.

• As always, have ways to receive warnings should any be issued.
• Make sure your safe space is ready to go. Sometimes thunderstorm winds can pack a punch.
• Alert those you know in this region to the possibility of severe weather so they can be prepared. Outdoor activities are abundant this time of year. Being outside and not prepared to take shelter in case of a storm is less than ideal.
• Don’t forget about the lightning danger from these storms. If you can hear thunder, you can be hit by lightning. Take shelter immediately.