Out of retirement for a short (long) post on March severe weather potential in Michigan

Note that this post doesn't represent a permanent return to the blogosphere, but I felt that I needed to make a post here being that we're in a rather exceptional situation this year and what I have to say would be a bit unwieldy to squeeze into a Facebook post. I may continue to make posts like this from time to time, but don't expect anything regularly.

To business:

The two long-range models I trust the most (the GFS and ECMWF aka the Euro) are predicting a very rocky, stormy month for the Great Lakes and the Mississippi Valley regions.

There are two main reasons for this: abnormally warm, moist Gulf air surging up from the Gulf of Mexico, and the jet stream - the atmospheric engine that drives pretty much all of our weather patterns - is on the war path. Typical for this time of year, the jet stream tends to be a bit more amplified. Think of an amplified jet stream the same way you think of amplified sound. If the jet stream is more "zonal", it's flatter, and therefore not as loud (stormy). But when the jet stream is marked by numerous peaks (ridges) and valleys (troughs), you get air patterns violently mixing with each other. Ridges are marked by warm air surging up from the Gulf of Mexico, while troughs are marked by cold air being pushed down from the North Pole and Canada. We see this much more actively in the fall and early winter months and again in the late winter/early spring months. Keep in mind that meteorological spring starts on March 1st, which is today.

What is VERY atypical, however, is to see this kind of pattern over the Great Lakes region, at least in the manner it's manifesting. Normally, the jet stream will become much more amplified and sink very far south, bringing our typical winter temperatures and the occasional winter storm. What's happening this year is that we're getting a pattern a bit more like what you'd see in Oklahoma or Kansas. You can probably guess where I'm going with this - severe weather. With the record high temperatures we've been seeing come a jet stream which is much more oriented to our latitude. We tend to see this in the late spring and early summer months, and that's why our severe weather season corresponds to late May/early June. Instead, Michigan has now seen its second severe weather watch of the year to close out FEBRUARY. Consider that last year, we hardly had any in the state, and now, even before the start of spring, we've had two. This is a bit alarming, and it's making me wonder what's in store later.

Going back to the long range models, the pattern is expected to persist, at least for the first half of March. I'm noticing a very nasty looking feature in both the Euro and GFS that could arrive in about seven days. It's still wayyyy too early to predict what exactly is coming, but as of right now it definitely looks like a potential severe weather maker for the Great Lakes region, if not necessarily Michigan. The Euro looks especially nasty, and it tends to be the more accurate of the two during the winter months.

The latest two consecutive runs of the Euro, and to a lesser degree, the GFS, predict a strong jet stream to be aligned with the arrow on this map about a week from now.

The last two consecutive runs of the Euro indicate what I refer to as a "Kamehameha Wave", a nickname of my own. I'm a big Dragonball fan, and a few years ago I noticed that certain coupled jet features - especially at mid-level - look very close to the way the characters from that series form their energy attacks. In fact, it's a great analogy to exactly what's happening in the atmosphere. When the jet stream "decouples" and becomes separated into a northern and southern feature like this, one can assume there's going to be a TON of energy right in the middle. Provided that enough moisture streams into the "strike zone" - the area just to the east of the southern portion of the jet and in the warm sector - that energy can cause significant severe weather.

When this energy moves eastward into a warm, moist strike zone, all hell can break loose. Squall lines, supercell thunderstorms, and tornadoes all thrive in this environment. The Great Plains states tend to sit in this strike zone starting right at this time of year. With a jet stream typically further south across the central plains, these orbs of energy crash right into them just as meaningful moisture is surging back from the Gulf of Mexico. Only this time around, the moisture has been pouring into our area, bringing us ridiculously high temperatures for this time of year. As this pattern continues, more and more of these energy orbs are going to interact with it, leading to nastier and nastier weather.

Again, the jury is still out on the March 7th situation. It must be emphatically stated that this type of pattern is VERY ODD for Michigan, and patterns like this are by no means assured to stick around. I'm actually fairly surprised that it's lasted as long as it has - normally these types of things retreat after a few weeks, but not this time. An early spring may indeed be on the way to Michigan, but that spring might be a bit more like the Great Plains's version of spring, and to that end we'll need to be extra weather aware.