The storm’s from last night are now fading as they track SE over the lower Lakes towards the Ohio Valley but it’s an area south of there, generally from I-80 on south from west-central Illinois through the heart of Indiana into western and central Ohio which is a RED ZONE with a highly primed atmosphere late this afternoon and evening for strong thunderstorms to enter and are expected to cluster into a large and complex MCS’s (Mesoscale convective system) which will produce damage across a large area. Isolated tornadoes are possible as well as large hail and of course flash flooding.
As you can see from the title and the above and below charts issued by the Storm Prediction Center, there is now a HIGH risk area for this anticipated severe weather. As all the ingredients come together over this region with a LOT of energy racing SE at 500mb over top of a HOT and juicy lower atmosphere which is trying to push north, this becomes a highly volatile situation as the atmosphere is forced upwards well ahead of the complex of storms and so SSE winds at the surface are being sucked in while a powerful WNW winds roars overtop. This sets up a large area of twisting and turning with lapse rates through the roof, keeping in mind the level of heat the atmosphere is pulling up from the south by the system while cool/drier air gets pulled down from the north. Remember these LARGE systems intensify, fuel themselves as they use all the atmosphere surrounding them.
The worry is that as storms fire over southern Minnesota, northern Iowa, southern Wisconsin and race SE, they will encounter the hot, humid air with many thunderstorm clusters already fired up and travelling fast SE, with new storms forming before the main cluster catches up, this fast moving progression of events is likely to fan out into an ARCH orientation thanks to varying powerful winds depending upon elevation within the atmosphere. ‘Bow echoes’ or derechos will be the result and are expected to produce powerful, destructive straight line winds over large areas, sometimes hundreds of miles across.
UPDATE: The surface environment within the HIGH RISK AREA is now really ‘juicing up’ with dew points now near or at 70° while the air temperature is near 90°. This is perfect fuel for storms to feed off of late afternoon as they blossom upstream and get driven southeastwards along with the upper energy parcel.
Current dew points.
Source: weather.com
Current temps.
Source: weather.com
Models show the upper level energy crossing the high risk area later tonight into early Thursday morning. Strong thunderstorm clusters should develop and head SE into the hot, humid air late afternoon but it’s once the upper energy catches up, is the threat INCREASED with potential development of an MCS and derecho.
While there is a lot of focus centred this afternoon and throughout tonight over Illinois, Indiana and Ohio, potentially extending into Pennsylvania tomorrow morning, there is also a HEIGHTENED risk area outlined by the SPC for the Mid-Atlantic for tomorrow afternoon and night.
Check this out.
More information and video shall be available later, stay tuned!
[s2If current_user_can(access_s2member_level1)]
[/s2If][s2If is_user_logged_in() AND current_user_cannot(access_s2member_level1)]
That’s it, [s2Get constant=”S2MEMBER_CURRENT_USER_DISPLAY_NAME” /]!
To continue reading, you need to have a valid subscription to access premium content exclusive to members. Please join a subscription plan if you would like to continue.[/s2If][s2If !is_user_logged_in()]
Sign in to read the full forecast…
Not yet a member? Join today for unlimited access
Sign up to markvoganweather.com today to get unlimited access to Mark Vogan’s premium articles, video forecasts and expert analysis.
[/s2If]
Recent Comments