Possible Severe Weather For The GMR
This year’s Great Midwest Relay is Friday June 8th and Saturday June 9th. The GFS (Global Forecast System - a long term model that we use to forecast more than a week in advance) has been consistently bringing a weather system across the Midwest during that time period for the past week. With 7 days or more of consistent solutions pointing to this scenario, it is starting to make me a little nervous. When the GFS is that insistent on a scenario for that many runs in a row, it usually means something.
To add to my concerns, the Storm Prediction Center placed all of northern Illinois and most of southern Wisconsin in a possible risk area for severe weather in their Day 4-8 extended outlook. They are placing the risk on Days 7 and 8, which lands exactly on the GMR, June 8th and 9th. Here’s the graphic and an excerpt from their outlook:
” …The upper flow pattern should begin to transition on or near Day 6, as the eastern trough lifts northeastward downstream of a second trough moving across the Rockies. The main severe threat should exist across the High Plains on Day 6, as height falls begin spreading out of the Rockies.
The GFS is more bullish for severe weather on Days 7 and 8, as it brings a much stronger trough eastward into the central continental US than the ECMWF. Either way, both models spread strong mid-level southwesterly winds across the central continental US and the Midwest ahead of the trough, which should support a continued threat for widespread severe weather through the end of the period. “
Now, keep in mind that we are still a full week away from the event. [Insert Chicken Factor Here] This is just a preliminary guess and any of the ingredients in this setup could change over the next few days. I’m just trying to give everyone a heads up that we may be looking at a pretty active pattern for the event. I’ll have another update for you soon, probably the end of the weekend or Monday, once I see how things evolve. If this event stays on track, we could have a pretty interesting start to the Great Midwest Relay.
