Current Forecast Meet the Forecaster

Issued: 8pm on Sunday, July 20th 2025

Technical Forecast Discussion

Short-Term Forecast (Sunday 07/20/2025 through Tuesday 07/22/2025):

An upper-level blocking high will begin to develop during the short-term. As a minor trough pushes eastward today, a surface low will traverse southeast and finally bring the Ohio Valley region sunny conditions. However, moving into Monday and Monday evening, a prominent ridge aloft with a prominent region of upper-level convergence and surface divergence will promote stable weather in the coming days. As this ridge rapidly builds in the coming days, a wider gradient of geopotential height will build as it trends to expand at 500 mb. This region of sinking air includes much of the eastern half of the CONUS, and with warm air from the south and dry air from Canada, we can likely expect heatwave-like conditions this week. These conditions are expected to persist past the short-term as a surface high slowly builds into the region. Sunday night through Tuesday, weak positive vertical velocity values between 850-500 mb will only support sinking motion in the region. Despite the heat this week, moisture at the surface will drop considerably, making it feel relatively comfortable regardless.

Long-Term Forecast (Wednesday 07/23/2025 through Saturday 07/26/2025):

As previously mentioned, high-pressure at the surface and aloft will continue into the long-term. The ridge aloft will only develop further and trap hot air in the eastern CONUS region. 500 mb height tendency will continue to expand for most of the long-term as a continuation of sinking air throughout the troposphere persist. Wednesday and Thursday will continue these stable weather patterns, though a minor change of this pattern could pop up Friday into Saturday. While most of this week will be dry, a minor trough will follow behind the large ridge with a small, embedded shortwave both Friday and Saturday. Storm chances are not immensely high, but a conditionally unstable atmosphere both Friday and Saturday with an approaching cold front at the surface could help convection to occur. Southwesterly winds will transport moisture throughout the atmosphere towards Ohio, allowing instability to develop. Relative vorticity levels are not strong Friday, likely leading to short-term showers and thunderstorms if they are to develop. Saturday will have stronger vorticity values throughout 850-500 mb, while vertical velocity will only support rising motion Friday and Saturday as well.