00:00Well, it's been a very active time, the peak of severe weather season, arguably from mid-April
00:05into early May, and we're there. We are dealing with an active stretch every day, even on our
00:11down days like Thursday, still some severe storms in some areas, but on the up days in a bad
00:19situation, we're dealing with occasional high risks of severe weather, and that is three out of four
00:23on the AccuWeather Severe Threat Index. Let's take a look at what's going on here as we move
00:27into the latter part of the week. We're going to look at a few of our forecast graphics in a
00:31moment,
00:31but I wanted to give you the big picture of the current disturbance that's moving into the western
00:37U.S. So here we are Thursday, and you can see these bright colors. I know it may look like
00:41almost
00:42nonsense, but these bright colors are measures of vorticity or spin in the atmosphere, and this is
00:48the upper level flow. There's a big trough across the west. We can plot that strong low pressure system
00:53moving through western Montana. There's been some snow tide to that, and then we look a little
00:57farther east, and there's a feature that may not catch your eye quite the same, but this
01:01short wave, that's a disturbance that's moving east, and this is going to be sparking some severe
01:06storms on Thursday east of there into parts of the Great Lakes area, and even down into some
01:11sections of the southern plains, some risk of severe weather. But I really want to focus on Friday
01:16because this next system that digs into the plains is a relatively sharp trough, and it's a strong
01:22storm system with a pretty vicious cold front associated with it as well. And this is going
01:28to be the game changer that eventually ends this spell of near record and even record-breaking heat
01:33in the eastern U.S. this weekend. But sometimes the relief from that comes with some pain in terms
01:39of severe weather in the plains, and you can see it's a really significant trough that moves through
01:44on Friday. So it emerges from the Rockies into the plains, and I'm just kind of scrolling through
01:49one example. That's the GFS. Here's the NAM, another model, and the European, all generally
01:54with the same message. There's a deep trough that's entering the plains from the Rockies
01:59on Friday. So areas east of there, we have several different ingredients at play. There's a persistent
02:06ridge of high pressure down over the Gulf that's impacting Florida with the drought that's been a
02:11problem. And then coming out of the Gulf, we've got low-level moisture, but upstairs there is wind
02:17from a different direction. And you can see the winds are going to be kind of twisting as we go
02:22higher up into the atmosphere here. So we're looking at some wind shear. Now the wind shear is
02:26going to be greatest in the Midwest. I was kind of drawing that maybe a little farther south than I
02:29should. So we're concerned about how these storms will behave on Friday. By the way, Friday at 2 p.m.
02:36eastern or noon mountain time, no storms popping yet, but we have snow there in parts of Colorado.
02:41We're actually forecasting 6 to 12 inches of spring snow in the Colorado Rockies. And we might even see a
02:47little bit of a wintry precip into eastern parts of the Dakotas. But watch what happens Friday
02:51evening. We go from nothing to storms erupting in Kansas and Missouri and into Illinois Friday
02:58evening and Friday night. And these will be pretty aggressive. And here's another opinion here. Here
03:03we have the European that even shows on a slightly smaller scale, these different plumes of heavier
03:08rain with those splotches, those streaks of yellow. So this model is able to resolve the scale of some of
03:14these clusters of storms that some may be rotating. In fact, if we go over to this product, this is
03:19CAPE. This is convective available potential energy. Basically, this concept of warm humidity to the
03:24ground and colder air aloft. And Thursday, there's some CAPE as we go through different models. But
03:31Friday, it's going to be present along with more significant wind energy aloft. And you can see in
03:37the NAM, we can see a pretty big spike of very strong CAPE values. So you get into those oranges
03:43and reds, you're getting up to 3,500, maybe near 4,000 joules per kilogram. And that's the unit of
03:50measure here. But this is a measure of energy that's basically fuel for updrafts in the atmosphere
03:55here. And again, the NAM showing us the strongest signal there in the early afternoon, getting those
04:00updrafts going. Eventually, maybe actually later in the day when we actually see these updrafts have
04:04enough traction to work through a little bit of a warm layer near the ground and really get going.
04:10I wanted to show this product here. This is called the Significant Tornado Parameter. And it's kind of
04:16a, it is a mathematical product of a few different weather variables that highlight instability,
04:22shear, helicity, and the potential for stronger tornadoes to form. And a lot of the time, for example,
04:29Thursday up in Syracuse, we're talking about severe weather. You see a little bit of a hint there,
04:34but not a strong signal. So it's mainly a damaging wind risk, maybe a very isolated tornado there. But
04:40look at Friday, we begin to see, again, a bit of a stronger signal in Oklahoma, where we hit even
04:46the oranges and yellows there with a significant tornado parameter present. We have to be concerned
04:52about possibilities of tornadoes on the southern side of the storm system in the plains. But as we go
04:57back to the forecast graphics, I want to focus on this area. So again, from the southern plains all the
05:02way up to the Midwest, we're probably going to see a lot of hail, a damaging wind with some tornado
05:06threats to the north, and perhaps some nasty tornadoes isolated, but intense potential for
05:12tornadoes down into the Oklahoma area and eastern Kansas. We had a couple of EF2 tornadoes earlier
05:17this week in eastern Kansas, by the way. So Friday, we're looking at a three out of four. That's high
05:23risk for the AccuWeather scale there for Des Moines, Iowa, and St. Joseph, Missouri, Kansas City,
05:29and then Lawrence, Kansas. Those are four population centers in or on the edge of our high risk for
05:35Friday into Friday night. And we're concerned about tornadoes, destructive hail, and damaging
05:40straight line winds. So large hail, very strong winds. And here again, we have the meter pointed up
05:46there. And the risk for tornadoes is more significant in the southern half of this area, but still also
05:50some risk of tornadoes up near the triple point where the warm front and the cold front meet. So a
05:55few
05:55different competing variables kind of bringing us the risk of tornadoes. I wanted to briefly
06:02take you back here just to show the Saturday risk zone. Saturday storms do move east into parts of
06:08the Ohio Valley. We're going to get a little hint of drought relief there in the Carolinas, but not
06:12nearly as much as we'd like on Sunday. So Saturday storms do move east. And again, there's some risk
06:18for severe weather for many areas, but the parameters are not quite as intense as on Friday.
06:25So Saturday and Saturday evening, we have lots of moisture, some warmth, and we also have some,
06:33I guess I would say, medium amounts of jet stream energy with this one because the core of the storm
06:39system is actually lifting up into Canada. So this is where it lands us, a large area on Saturday with
06:43some risk for severe weather, but a moderate risk there in part to the Ohio Valley. That's your forecast
06:48fee.
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