St. Louis, Missouri – Temperatures more typical of June than early spring are spreading rapidly across the central and eastern United States, with some areas climbing into the 80s and 90s during the April 1–7 period as a massive heat dome expands east.
According to the National Weather Service Climate Prediction Center, a strong high-pressure system has established itself over much of the country, creating a classic “heat dome.” This setup traps warm air beneath it like a lid, while sinking air compresses and heats further, allowing temperatures to surge 20 to 30 degrees above seasonal averages.
The pattern began in the Southwest, where parts of Arizona and California already exceeded 100°F, breaking March records across multiple states. Now, that same dome is shifting into the Plains, Midwest, and eventually the Mid-Atlantic, bringing widespread above-normal temperatures with a 70–90% probability of warmth in many regions.
Cities from Kansas City and Chicago to Cincinnati and Washington, D.C., could see prolonged stretches of unusually warm days paired with mild overnight lows. This reduces cooling relief and increases early-season strain on energy systems, especially as homes and infrastructure are not yet adapted to sustained heat.
Unlike typical spring patterns, cloud formation is suppressed under the dome, meaning more direct sunlight and fewer cooling rain events in some areas. Where rain does occur, it will be brief and driven by passing systems along the edges of the heat zone.
The heat dome is expected to persist through much of April 1–7 before gradually weakening, but additional advisories may be issued as record temperatures and early-season heat risks continue to expand.
