Our current wind out of the southwest in southern MN certainly doesn’t set the table for much severe weather, but winds will be shifting and will become more southerly through the day. With that said, we’re not expecting a widespread severe weather outbreak here in southern Minnesota and northeastern Iowa later today. The bulls-eye for severe weather this afternoon and evening is in western Iowa and eastern Nebraska, although I do expect we’ll have a few severe storms in the mix locally, later today. The SPC has put us in the “Slight Risk” for severe storms, while there is a “Moderate Risk” to our southwest.
So, yes, there is a chance for severe storms, but no, the expectation isn’t for every thunderstorm to go severe, for widespread thunderstorm damage, or for a bevy of tornadoes to form. Simply, we should all be aware of the potential for a few severe storms in the mix of otherwise loud but beneficial, heavy-rainers late today. It is indeed May. This is not “dismissing,” but is simply trying to reinforce the fact we needn’t be expecting Reed Timmer and his merry band of iron-clad chase chariots to roll into town later today – although they may be within a few hundred miles of us this afternoon.
It’s not feeling too muggy out there right now. Dew points in the 55-60 degree range make for noticeable humidity but not uncomfortable. Dew points will increase later today, but we still won’t hit the level of “sticky and uncomfortable,” or “unless you drink a lot of water you’re totally going to pass out after running laps at softball practice.”
Still, there will be ample moisture to feed thunderstorm development later today. The 3 basic ingredients for any storm are moisture, lift, and instability. Winds will increase moisture, sunshine is providing further instability, and a warm front and surface low will provide the lift later today.
One of the bigger questions for the development of thunderstorms, and the potentially more intense thunderstorms, is where a warm front will end up by the late afternoon to early evening.
The converging winds along the front will make for a zone of increased lift and wind shear. This means tornadoes can’t be ruled out from the stronger storms – if they develop. The mere mention of this possibility does not mean we’re summoning Helen Hunt and Bill Paxton to drive 10 hours to catch an EF-5, or for the Robin Hood: Men in Tights guy to inadvertently drive right into a tornado. There is, after all, a fine line of rhetoric in this business.
I’m not finding this morning’s model run to be very helpful in the afternoon placement of aforementioned warm front, so we’ll have to keep a close eye on the surface winds later today.
There’s my morning update. I doubt you’ve made it this far, but if you did – thanks! I’m going back to my coffee now. Enjoy the sunshine!
This post was written by Randy on May 2, 2012