A significant surge of summer heat is expected to develop across the Delmarva Peninsula during the second half of the week, with forecasters increasingly concerned about potentially dangerous heat and humidity levels by Thursday and Friday.
After a relatively warm start to the week, a warm front is forecast to move north through the region on Wednesday. This will open the door for a much hotter and more humid air mass to overspread the Mid-Atlantic, setting the stage for the hottest weather of the season so far.
Current forecast guidance indicates Thursday will likely be the peak of the heat wave. Strong southerly winds behind the warm front will transport very warm air into the region, allowing temperatures to climb well into the 90s across much of Delmarva. When combined with increasing humidity, heat index values could reach or exceed 100 degrees during the afternoon hours.
While there remains some uncertainty regarding Friday’s temperatures, confidence is high that the region will remain uncomfortably hot. Some forecast models suggest an upper-level ridge could strengthen over the East Coast, resulting in temperatures even warmer than Thursday. Other solutions indicate a weak disturbance could bring additional clouds and slightly lower temperatures. Regardless of the exact scenario, widespread highs in the 90s are expected.
The humidity will play a major role in determining the overall impacts of this heat event. Persistent southerly flow will continue to transport moisture northward from the Gulf and Atlantic, keeping dew points elevated. This combination of heat and humidity will increase the risk of heat-related illnesses, especially for those spending extended periods outdoors.
Residents are encouraged to stay hydrated, limit strenuous outdoor activities during the hottest part of the day, and check on vulnerable individuals, including the elderly, young children, and pets.
Relief from the heat appears possible over the upcoming weekend as a pair of cold fronts approach the region. The timing of these fronts remains uncertain, but they should eventually bring cooler temperatures and a reduction in the threat for extreme heat.
For now, Delmarva residents should prepare for several days of summer-like conditions, with Thursday currently appearing to be the most dangerous day of the upcoming heat wave.
