This afternoon, summer is making an early cameo across the lower Mid-Atlantic. A building high-pressure ridge over the eastern third of the country, paired with a classic “Bermuda High” anchored in the Western Atlantic, is driving temperatures way up.

Expect a very warm afternoon with plenty of sunshine and strong atmospheric mixing.

The Heat is On (But the Humidity is Hanging Back)

Models are in lockstep agreement that inland temperatures will climb into the lower 90s today. If you are closer to the coast, a developing afternoon sea breeze will keep things a bit more manageable, with highs capping out in the mid to upper 80s.

The Silver Lining: While it’s going to feel like July out there, early morning dewpoints are mixing out and falling back into the 50s. Because the air is relatively dry, heat index values will stay near or even slightly below the actual air temperature. It’s hot, but it won’t have that oppressive, swampy weight to it just yet.

A Lucky Few Might Catch a Storm (4:00 PM – 6:00 PM)

If you are hoping for some rain to cool down your lawn, odds are against you—but there is a sliver of hope. A weak “lee trough” just inland might provide just enough of a spark to trigger a few isolated showers or storms between 4:00 PM and 6:00 PM.

• Where: Mainly areas north of Richmond, the Virginia Northern Neck, and the Lower Maryland/Virginia Eastern Shore.

• The Odds: We are looking at a 20% chance of precipitation. High atmospheric caps and low moisture mean most of the region will, unfortunately, stay completely dry.

Any stray storms that do manage to break through will clear out quickly within a few hours of sunset, leaving us with a mild, clear evening and overnight lows in the 60s (near 70° at the coast).

Looking Ahead: Early-Week Sizzler

This summer-like pattern is locked in for the first half of the workweek. From Monday through Wednesday, expect widespread highs in the low to mid 90s each day.

Wednesday looks to be the absolute warmest day of the stretch due to “compressional heating”—a phenomenon where the air warms rapidly right ahead of an approaching cold front. Thankfully, afternoon dewpoints will stay in the upper 50s to low 60s, keeping the true humidity index in check.

The Memorial Day Weekend Twist: A Reality Check

If you are already planning your long holiday weekend, you will want to keep a close eye on the late-week forecast. The ridge of heat will break down by Wednesday night as a mid-level trough lifts into Canada, clearing the path for a strong, cool high-pressure system from the Great Lakes.

A cold front will push through our region late Thursday, triggering a major pattern shift:

• The Temperature Drop: Highs will plummet from the 90s down into the 70s for most of the area by Friday and Saturday. Parts of the Piedmont region
  might even struggle to get out of the 60s.

• The Weather: Expect a cool, onshore marine breeze bringing an unsettled mix of high-chance rain probabilities and drizzle.

While the exact rainfall amounts are still a bit uncertain due to how the marine layers are tracking, the upcoming holiday weekend is shaping up to look and feel vastly different than the 93° afternoons we are about to experience. Enjoy the beach weather early this week—you might need a light jacket by Friday!