Changes in the coming storm system, both in timing and track have created an increased threat for tornadoes on Friday. The Storm Prediction Center in Norman, OK pushed the slight risk further west, now covering most of Iowa on Friday.
A better handle of the tornado threat won’t come until early tomorrow morning, but the SPC indicates shear and hodograph profiles are in place for a tornadic day. They even go as far to say that a couple tornadoes could become strong (EF-2 rating or greater).
Of concern for chasers is the expected speed of these storms. Originally we believed strong, damaging winds would play the primary threat in this event, because storms could race at 50-60mph across the state. If theses storms keep that forward motion, chasing any tornadoes that develop will prove to be difficult. Warning times are also a concern because fast moving tornadoes can strike a place with far less warning than a slower moving twister.
It is also possible that any strong tornadoes that do develop could form out of slower moving storms. If development occurs far enough ahead of the advancing cold front, a rogue supercell could “break away” from the pack and slow it’s forward progress. Bad news for anyone caught underneath it but helpful when it comes to tracking and warning those in the path of the storm.
All in all looks like quite a busy day tomorrow for storm chasers and forecasters. With the threat spread out over a large area, hoping that storm chasers will not get in each other’s way. But with larger chase teams looking for something to do, there will likely be a lot of crews out tracking these storms.
We’ll follow the latest developments, and of course bring you the latest on tonight’s threat in western Iowa. We’re working with chase teams in western Iowa and eastern Nebraska and will share their information both tonight and tomorrow and more comes in.