⛈️ Delmarva Weather Update — Tuesday, July 21, 2026
Flood Watch in effect for New Castle County, DE and Somerset County, MD through 2:00 AM Wednesday.
Today's Weather Story: A warm front, approaching cold front, and a plume of tropical moisture are converging over Delmarva, setting the stage for widespread showers and thunderstorms — with the strongest activity expected this afternoon and evening. Highs land in the mid-to-upper 80s across most of the peninsula on a gusty south wind, and repeated rounds of rain will raise a legitimate flash flood concern, especially where storms train over the same spots.
Across Delmarva:
- Wilmington, DE: Showers & thunderstorms likely, high 87°F, S 5–15 mph (PoP 73%)
- Dover, DE: Showers & thunderstorms likely, high 89°F, S 5–15 mph (PoP 69%)
- Georgetown, DE: Showers & thunderstorms, high 88°F, S 5–15 mph (PoP 89%)
- Lewes, DE: Showers & thunderstorms, high 89°F, S 10–15 mph (PoP 78%)
- Cambridge, MD: Chance showers & thunderstorms, high 72°F, S 7 mph (PoP 39%)
- Salisbury, MD: Chance showers & thunderstorms, high 89°F, S 6–14 mph (PoP 70%)
- Ocean City, MD: Storms likely later, high 84°F, S 12–17 mph (PoP 70%)
- Chincoteague, VA: Storms likely later, high 86°F, S 10–17 mph (PoP 70%)
Active Weather Alerts:
- Flood Watch — New Castle, DE and Somerset, MD — until 2:00 AM Wednesday (NWS Mount Holly).
Severe Weather Outlook: SPC has Delmarva under an Enhanced Risk for severe thunderstorms today, covering Wilmington, Dover, Lewes, Salisbury, and Ocean City. Damaging wind gusts and locally heavy rain are the primary threats, with an isolated tornado not ruled out given the moisture-rich, sheared environment. WPC flags excessive rainfall/flash flood potential over the region, aligning with the Flood Watch already posted for New Castle and Somerset counties. Day 2 (Wednesday) trims to a Slight Risk that shifts toward the lower Eastern Shore and Virginia coast.
Why This Setup: A slow-moving cold front is riding into deep tropical moisture ahead of a nearby low, and an upper-level disturbance is providing the lift to fire organized, efficient rain-producers. That combination — high precipitable water plus repeated cells — is what drives the flash flood language.
Looking Ahead: Storm chances linger into Wednesday, especially south, before drier air begins to filter in behind the front late in the week. Highs stay near seasonable through midweek.
Bottom Line: Plan around the afternoon and evening storms today, keep an eye on radar, and don't drive through flooded roads — especially in New Castle and Somerset counties.
— US Weather Warriors 🌪️ #DelmarvaWeather #DEwx #MDwx #VAwx