Current Forecast Meet the Forecaster

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):

The long-term period will bring subtle but important changes to the overall pattern. While the upper ridge continues to dominate the Southeast and lower Ohio Valley through midweek, ensemble guidance suggests gradual deamplification by late Wednesday into Thursday as multiple shortwave troughs from the northern tier press eastward. The weakening of the ridge may allow a weak frontal boundary to sag southward toward the Ohio Valley by Thursday or Friday. However, deterministic model solutions vary on the southward extent and timing of this front, with some keeping it just north of the region. Should this boundary reach southeastern Ohio, it could introduce slightly better chances for scattered convection Thursday and Friday, especially during peak heating. However, given the lingering influence of the ridge and poor mid-level lapse rates, widespread precipitation remains unlikely at this time. Any storms that do develop may be slow-moving due to weak steering flow and could pose a localized flooding risk. The overarching theme of above-average temperatures continues through the period, though the weakening ridge and potential for increased cloud cover could slightly temper highs late in the week. Still, excessive heat and humidity will remain a significant concern through the entirety of the forecast period.