June 5 Severe Threat & Chase

The 8 AM SPC severe weather outlook has upgraded a large portion of the plains to a high risk, with the upgrade coming on the heals of increased damaging wind potential. The setup is very unique for this time of year, as the features in the mid and upper-levels are more like an early spring severe weather outbreak. These features, combined with early summertime thermodynamics will make for a nasty outbreak for severe weather. The large question in place is due to the early spring-like features of the wind fields, with a lot of shear, but overall unidirectional wind fields in mid to upper levels will result in fast storm motions and a push for more linear storms. This is the reason behind the high risk upgrade, as it is felt that as storms evolve into a potentially bowing linear structure that a significant damaging wind event may occur.

Despite this feeling, the tornado threat with storms is still quite high, and wording still includes the potential for long-track and significant tornadoes. The surface features will become better defined as we reach the afternoon hours, currently it is believed that the surface warm front has already surged northward and has situated along a line from near Sioux City eastward to Davenport given latest surface analysis. The low pressure is currently in northwest Kansas, pressure falls have already begun across central Nebraska and will pull this low north/northeastward. A dryline/cold front will be pulled to the south of this low and will also serve as a focal point for storm development late this afternoon. Other storms may develop along the warm front, nearly stationary front, draped approximately along its' same location now.

Chase Forecast: I won't be traveling far from my home area, with the warm front featured dead-center across northwest Iowa I can't venture far away from that feature. Although storm motions aren't the most favorable, given the amazing shear values it is likely that storms will quickly rotate and potentially produce tornadoes. I believe development should occur along the warm front late this afternoon, along with additional development along the dryline in central Nebraska and southward. Storms in each area can become tornadic, parts of the region, especially northwest or northern Iowa may see more than one round of storms. Initial development along the warm front will eventually either move north or be overtaken by a broken line of storms moving off of the dryline in the nighttime hours. This second line will also have potential of significant damaging winds...

Will be watching how things evolve, may either vote to head slightly west from the Spencer location that I'm currently at... Or may not need to move anywhere if warm front can fire throughout.