Issued: 8pm on Sunday, June 22nd 2025
Technical Forecast Discussion
Short-Term Forecast (Sunday 06/22/2025 through Tuesday 06/24/2025):
The dominant synoptic feature influencing the region through the short term will be an expansive and persistent upper-level ridge centered over the Ohio and Tennessee Valleys. This ridge is currently exhibiting strong 500mb height anomalies and will remain nearly stationary due to weak steering flow aloft and downstream troughing over the Rockies. The core of the ridge will remain overhead Sunday into Monday, maintaining extreme subsidence and clear skies while suppressing any meaningful convective development. At the surface, a broad area of high pressure will persist over the Southeast U.S., reinforcing southerly to southwesterly flow and continuing the advection of hot and humid air into the region. Overnight lows will struggle to cool efficiently due to elevated dewpoints and weak nocturnal boundary layer decoupling. By Tuesday, some slight flattening of the upper ridge is expected as a shortwave trough lifts out of the Northern Plains and toward the Great Lakes. This feature may nudge the ridge axis slightly eastward and lead to a slight increase in mid- to upper-level cloud cover. However, synoptic forcing remains weak locally, and the low-level thermal ridge remains parked over the Ohio Valley, so temperatures will continue to run significantly above normal with little relief in sight. Limited convective activity could develop on the northern periphery of the ridge late Tuesday, but this is more likely to remain north of the immediate forecast area.
Long-Term Forecast (Wednesday 06/25/2025 through Saturday 06/28/2025):