00:00In the forecast feed we have many days of thunderstorms to discuss here over the next five, six days.
00:07We're going to have daily strong and severe thunderstorms.
00:09The theme of June continues, although for the most part, while June has been especially treacherous in areas around Illinois,
00:17and there will be some severe weather in Illinois at the end of the week,
00:20a lot of the action through midweek is going to be focused a little farther west into more of the
00:26plains and not so much in the Midwest.
00:28So let's take a look at the short-term threat.
00:30By the way, a lot of these storms are going to be driven by overnight processes, so we're looking at
00:35some nocturnal convection.
00:37There's a great video on AccuWeather.com and some of the AccuWeather social media channels that Bernie put together,
00:43along with the social media team earlier this Tuesday, about the nature of nocturnal convection.
00:49A lot of this is going to be during the overnight hours.
00:52Now, there are going to be some storms and have been some storms in the evening in the area I'm
00:56circling,
00:56but the main thrust of this graphic is actually some overnight action that's going to develop over the high plains
01:02in eastern Colorado
01:03and dive down into parts of western Kansas and into northwest of Texas.
01:09And we're looking at damaging wind and hail, the main concerns with this.
01:13Let's take a look at some of the modeling here.
01:15And you can see the disturbance that will be driving this.
01:18It's kind of a subtle feature.
01:19It's not a big one.
01:21Overall, we have a strong ridge of high pressure over the southwest and parts of northwest Mexico.
01:27And adjacent to that, there are these spokes of energy that occasionally rotate through parts of the plains here in
01:34these troughs.
01:35But as we move forward, there's a subtle feature here that helps to spark this.
01:41You can see these little bits of vorticity by Wednesday morning, these little spikes of color.
01:46Those are going to be weak disturbances that move through parts of the high plains.
01:51But as we take a look upstairs, there is going to be a strong low-level jet.
01:57So we're looking about a mile up in the atmosphere, about 5,000 feet.
02:01And we have strong flow from the south that has origins over the western Gulf.
02:07So we can trace some of these streamlines all the way back to an area off the map over the
02:11Bay of Campeche.
02:12And while the low levels of the atmosphere near the ground cool down at night, and that makes that area
02:19more stable,
02:20aloft about a mile up, you're going to have this strong flow coming across Texas and fueling these storms with
02:26high dewpoint air,
02:28high moisture content, and this low-level jet.
02:30There's an example from the GFS.
02:32Here's the European.
02:34And again, late tonight, over the Texas Panhandle, a strong surge of wind from the south.
02:38And with that, you can see there is some pretty good moisture out there as well.
02:43We're looking at the mean relative humidity, so the average of the humidity between about one mile up
02:49and about four miles up in the atmosphere.
02:52And you can see some greens out there where there is some pretty good moisture surging north,
02:57partly because of that low-level jet.
03:00So rainfall amounts here.
03:02You're going to see some areas with an inch or two of rain through western parts of Oklahoma.
03:06And there are localized areas, localized hotspots.
03:10You can see the max here, 3.62 inches.
03:12That may end up being in western Oklahoma.
03:14So there's potential for, you know, localized two to four inches of rain,
03:17but widespread areas seeing one to three inches during the overnight.
03:22I'm going to kind of take this back to another product,
03:23and let's go back to our graphics here as we kind of focus the storyline into Wednesday then.
03:30And in Wednesday's forecast, through Wednesday night, more heavy rain, damaging wind potential,
03:36but especially heavy rain.
03:37We're focusing that heavy rain risk area into this general swath across the western plains
03:43down into areas around the lower Mississippi Valley.
03:45And Wednesday, we get into another severe weather setup here where there will be some scattered
03:50or isolated downpours that become intense in many areas across the central plains
03:55down into the southern part of the Mississippi Valley.
03:58But still, again, the primary area of the strongest of the storms will be focused over the high plains,
04:06western parts of Kansas into eastern Colorado.
04:08So there are some areas into Wyoming, Cheyenne, Wyoming, Sydney, Nebraska, Goodland, Kansas,
04:13this is Lamar, Colorado, Lamar in the southeastern part of Colorado in the high plains.
04:18Moderate risk here.
04:19That's two out of four on the AccuWeather four-tiered severe threat index.
04:22We're looking at the high plains, areas west of I-35 and east to near the Denver area.
04:28Damaging wind, hail, and frequent lightning.
04:30Going back to the graphics, here you can see into Wednesday and Wednesday night,
04:35another similar but perhaps slightly stronger dip in the jet stream here.
04:40These little kinks of vorticity, these little bits of energy, if you are east or southeast of one of them,
04:47and if they're headed your way, the atmosphere is going to be producing some extra rising motion.
04:51So another disturbance as the ridge down to the south of New Mexico flattens out a bit.
04:57These disturbances are kind of beating that down a bit.
05:00So Wednesday night to Thursday, here we are again with another strong bit of wind.
05:05The low-level jet, Tuesday, this is Wednesday night to Thursday morning,
05:09again producing pretty strong wind that has some origins over the western Gulf,
05:16driving the moisture pump back into areas around the southern plains,
05:20and some of that can be carried up into parts of Colorado.
05:23And again, there is some extra moisture in this area.
05:25And look at the dew point and the humidity.
05:27This is the mean relative humidity.
05:28It increases into the central plains, western Nebraska, parts of Kansas.
05:34Thursday, you can see the humidity levels are increasing here.
05:37Some of this being driven by a disturbance rounding the northern part of that ridge,
05:42rounding through the northern Rockies,
05:44but some of this also being contributed to from that flow from the south.
05:48And now we're getting into this second episode, Thursday, Thursday night,
05:52where more and more areas are seeing 1 to 2, 1 to 3 inches of rain, localized pockets.
05:56I see a forage here somewhere over west-central Kansas near Interstate 70 here.
06:01So again, there's potential for some flash flooding out there.
06:04Let's take it back to the graphics to round this conversation out.
06:07And then we get into Thursday afternoon and Thursday night.
06:10And we added two moderate risks.
06:12This is a new development from our afternoon discussion this afternoon, this Tuesday afternoon.
06:17So now we have two moderate risks here.
06:20We had a large sub-risk, but now we're kind of getting a little more specific.
06:23And into Thursday, here we have Wichita, Kansas.
06:27And we're looking at a median risk of flash flooding and damaging wind and hail through Thursday evening and Thursday
06:33night.
06:34It's going to be scattered, but the potential is there.
06:36And again, this is just the risk of flooding is escalating because of multiple days in a row.
06:40And we'll close with a look at the Denver forecast for Thursday evening and Thursday night.
06:44Some of these will be severe with damaging wind and hail concerns there as well.
06:48That's your forecast feed.
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