00:00We made it to June. We've been talking a lot about the hurricane season. Well, let's take a look at
00:05kind of a checkup on the severe weather season, severe thunderstorms, tornado counts, that kind of thing for the U
00:12.S.
00:13We are past the peak of the severe weather season. It really occurs in mid to late May, but we're
00:19very much still in severe weather season.
00:22It just begins to change character and shape here as the band of severe weather in the U.S. begins
00:29to shift north into the true summer months.
00:32So how are we doing so far? Let's take a look at the graphics here. I'm going to get myself
00:37out of the way.
00:38Here is the count of tornado reports. Not precisely true tornadoes, but tornado reports.
00:45The number of tornado reports is generally correlated to the number of true tornadoes.
00:50But again, sometimes you may get some redundancy if you have a long track tornado that goes over many miles.
00:57You're going to have multiple reports for that, even if they're filtered down through some statistical methods.
01:02Regardless, here's the baseline. The blue is average. The blue is the statistical historical average.
01:08And this orange line is this year. And this year we're running just a smidge quieter than average.
01:14Not by much, though. We're running a small percentage quieter than the norm.
01:21There have been many times from mid-March through early May when we were actually above average here,
01:26when the orange line was above the blue one. You can see the big step ups.
01:29The steps here, these were tornado outbreaks or very active stretches where you had many tornadoes in a short period
01:36of time.
01:36And then the flatter times, where we have not seen as much severe weather.
01:41And again, it kind of stair steps up here, but our biggest outbreak by far was, we had a couple
01:47of them really,
01:48March, mid-March, and then mid-April another one.
01:51May was actually pretty friendly to us. We started May above average and ended May a smidge below average.
01:57So where have these tornadoes been occurring?
02:00Well, Illinois is still atop the list here when it comes to the number of tornadoes.
02:05121 tornado reports in Illinois.
02:08And the remarkable thing here is that I think there was only one in the month of May in Illinois.
02:14So most of that is really from the earlier part of the spring.
02:18Mississippi has been playing catch-up a little bit with 82 reports.
02:22But we have not yet had a tornado report filed in Pennsylvania yet this year.
02:27There actually have been a couple of tornadoes confirmed by survey in West Virginia,
02:31but you can kind of see the disparity here, even though West Virginia hasn't had any tornado LSRs,
02:36tornado local storm reports.
02:38So again, it's not totally one-to-one tornado report versus confirmed, but it gives you the general idea.
02:45Now, tornado occurrence by day.
02:47This gives us a little context on where we are here.
02:49I'm going to pick the beginning of June.
02:51This is still very much in this big chunk of the mid-spring, really end of winter through the spring
02:58into the early part of summer when we see the most frequent tornado activity.
03:02But we have a ways to go here.
03:04We have a ways to go the gradual decline into the winter.
03:08So what is on our mind here regarding concerns this week?
03:12This week we have repetitive rounds of severe weather rumbling through the central plains.
03:16And when we take a look at the upper-level flow, first thing that jumps out to me is this
03:22strong zone of low pressure
03:23over the southern part of the Canadian Rockies, western parts of the Prairie Provinces.
03:28And again, we have this zone here where we're going to be dealing with multiple spokes of energy rotating around
03:35the base of that trough.
03:37And each of these will be entering the plains, especially the Dakotas, and driving some severe storms in those areas.
03:44So these little spokes of energy here, these little blips of brighter color, as they rotate around the base of
03:50that big trough,
03:52that's going to be sparking some more storms.
03:54And we're going to get one of them on Tuesday evening, another one Wednesday.
03:58And actually the trough begins to slide east.
04:01And around the base of that trough, we will have a front and, again, more jet stream energy kind of
04:07rotating through the base of this.
04:09That's going to spark some more strong and severe storms.
04:13There will also be some noise down in the southeastern U.S., the base of this cold front, this trough
04:19here.
04:19I'm going to mark it as just a trough.
04:22As this kind of wags its tail down through parts of South Carolina and Georgia,
04:27we'll likely see a few more intense thunderstorms down that way as well on Tuesday evening and Tuesday night.
04:33Moving forward into the weekend, you can see that disturbance here Friday.
04:37This is going to likely produce some strong and severe storms into the upper Midwest.
04:41Areas around Minneapolis, for example, could be at risk here on Friday evening.
04:45Now, when we look at some other parameters, here's the explicit forecast of where the thunderstorms will be,
04:50where precipitation will be occurring.
04:52You can see the Dakotas, the favored spot here, and all the way down into eastern New Mexico, Tuesday, Tuesday
04:58night.
04:58Wednesday takes a step farther east as that storm system rolls east through the Canadian prairies.
05:03Then Thursday, we will see some more storms fire over the Dakotas again.
05:08And then into Friday and Friday night, eastern parts of the plains, areas like northern parts of the Midwest,
05:16so Minnesota, on Friday will be at risk of severe storms.
05:20All the while, though, you can see a strong ridge of high pressure kind of camping out over parts of
05:26the interior east.
05:27So that's going to be an area where we are resistant to rain, and generally dry weather will prevail, for
05:34the most part,
05:34with a few exceptions Tuesday, a few downpours in the area near the Blue Ridge.
05:38Most of the remainder of the week will be dry for the eastern half, eastern third, I should say, of
05:43the nation.
05:44Another product here, we can look at Cape Convective Available Potential Energy.
05:48This is a look at the lift, the fuel for rising motion in the atmosphere, in the Dakotas down to
05:53Texas, Tuesday.
05:55Generally, in the eastern Dakotas down to Texas, Wednesday.
05:58Thursday, South Dakota down to Texas.
06:00You can see a repetitive pattern here.
06:02And then it focuses a little farther east for Friday, southern Minnesota down to Texas yet again.
06:07So what does this do for us with our forecast?
06:10Well, this is what we are communicating, at least when it comes to our forecast communication here.
06:17On Tuesday, we're looking at a two out of four risk.
06:20It's moderate on the AccuWeather four-tiered severe threat scale for North Dakota, western South Dakota, eastern Montana.
06:27Then into Tuesday afternoon, secondary zone near the tail of that trough into south Georgia and Florida.
06:33Then we have another risk on Wednesday afternoon and evening in the Dakotas.
06:37And again, then on Thursday, a larger zone back into the Dakotas.
06:43And we'll soon have a map out, most likely for parts of Minnesota for Friday.
06:47That'll be next on the list.
06:48That's your forecast feed.
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