KANSAS CITY, Mo. — The moisture will be flowing into the region today on strong south winds that will be gusting to close to 45 mph (perhaps higher in spots). This is just one of many ingredients that we look for with a storm setup arriving tonight in the form of a cold front/dry line that will usher in cooler and much drier air at some point.

What makes this forecast tricky is how long we keep the thickest moisture around today. You will feel it this afternoon, but the issue is whether the moisture get pushed east toward areas southeast of Kansas City, or if it hangs tough across eastern Kansas so that when other ingredients come into play, we can fire off a line of storms.

That will be worked on today utilizing satellite and short-term model data, which should help us out more with the timing of all of this. My concern remains from 8 p.m. to 2 a.m. tomorrow.


Kansas City Forecast

This afternoon (1PM Update): Becoming partly cloudy, very windy and warmer. Highs surge into the mid-80s on strong south winds gusting over 40 mph. A wind advisory is in effect for the region.

Tonight: The strongest risk of storms is after 10PM through 2 a.m. tomorrow. Storms may initiate just toward the west and northwest of the metro and roll down toward us between 11 p.m. and 1AM.

Tomorrow: Blustery and cooler with highs in the lower to mid-50s.

Thursday: Nice with still leftover cool weather. Light freeze in the morning with afternoon highs into the upper 50s.



Today’s forecast has lots of ifs, ands or buts involved. Typically when it comes to severe weather we look for several things to come together:

1) Moisture. Well no doubt about that. We will have that flowing into the region today from the south.

The map below shows the temperatures/dew points. The dew points are dashed and the higher dew points are in green. During this time of the year, we really start looking for dew points preferably into the 60s to get the storms really cranked up.

So the moisture is coming up as I type this.

Now the next ingredient is having some sort of focus for this moisture to work with, some sort of front. Not only will we have colder air moving into the Plains tonight, the same storm will also allow a significant drop in dew points to move into the Plains today.

The winds out there will be howling and farther west there is concern for fire weather and spreading grass fires with the winds gusting to 50 mph or higher. This will also generate blowing dust. I bring that up because that dust will get into the developing storms tonight, and we may have some “mud rain” from what blows through.

This moisture in the form of higher dew points should hang around today. Then as the cold front/dry line moves into eastern Kansas overnight, storms should pop on the dividing line between the gulf moisture and the drier central Plains air.

Yesterday the dew points in western Texas crashed to minus 25 degrees… absurdly low. The relative humidity, since the dry air heated up so much, well into the 80s, was an astounding 1% at one point.

It won’t be that dry, but an overall bone-dry atmosphere will be just toward the west of the area later today. The dividing line is what we watch for storms.

Initially, the temperatures aloft will be too warm to support much development, but overnight the mid-level temperatures will be dropping. That results in the cap breaking. This is another ingredient.

2) Wind shear. There are two types, the first is directional shear where the winds go from one direction close to the ground to another direction thousands of feet up. Directional shear can be more pronounced in various levels of the atmosphere, but we especially look for it in the lower 4-6 miles of the atmosphere.

Another type of shear is speed shear. The winds, as you go up increase with height. The faster the increase, the more likely we could see storms exhibit rotational characteristics. When both are working together, it can be much more concerning.

The latest surface map shows the surface storm coming into the Plains and moving towards the northeast.

The latest from the Storm Prediction Center is this for today:

Here is a blow up of things for our area:

The main risks overnight appear to be winds and some hail. There is a non-zero risk of tornadoes, and while not that high at this point, the leading edge of these lines always bear watching for these little spin-ups.

Typically they aren’t the big honker tornadoes that struck other parts of the country last Friday, but they must be watched in case they try to form tonight.

There are bigger concerns about this across the southwest parts of Missouri into perhaps central Missouri for tonight.

1PM Update…model data is converging on roughly this solution for storm initiation…roughly near or after 10PM. The animation starts at 8PM each hour

So what are the “failure modes?” In other words, how can the KC metro miss out on most of this? It’s on the table. If we end up drying out the air this afternoon to a large extent, this would essentially starve the storms from developing because despite the higher heat, there would be no “gas” for the storms to fire on.

Another failure mode could be if things happen, but farther toward the southeast of the KC area. This is on the table as well.

We’re sitting around and waiting and waiting this evening, and voila! All of a sudden the storms pop, but pop towards the southeast of the metro. The way this happens is if the dividing line between the gulf moisture and the drier air is southeast of the KC metro area.

Right now, I think storms are more likely than not.

The feature photo is from Matthew Smith near Knob Knoster, Missouri, from Sunday night.

We’ll have the team all lined up for coverage as we need it through the night.