Thunderstorms possible Tuesday night in KC
KANSAS CITY, Mo. — Hello bloggers,
There is a slight risk of severe thunderstorms later tonight as a storm system develops and moves across the plains. This is a level two out of five severe weather hazard level and there are quite a few questions about this severe weather hazard. We will examine this risk in this blog entry.
For severe thunderstorms to develop, we need to bring together the ingredients of the thunderstorm. Let’s start with humidity. If there is no low level humidity (higher humidity), there will be no thunderstorms. The air from the Gulf of Mexico is the first ingredient to look out for when we forecast thunderstorms. As you can see below in this dew point forecast map, the moisture supply for this storm system is limited:
Dew points should be in the 50s. The nearest 60 degree dew points are well south of Texas, and that’s the forecast for 6 p.m. tonight. Now, that could be a few degrees too low, but if it’s at all close to correction, thunderstorms will have limited moisture input to maintain their strength, initially. I say first because the humidity will rise after sunset tonight, then it will only be a little higher on Wednesday, as you can see below:
Now I know it’s a bit complex. Take a look at the sliver of higher dew points near Memphis at 4 p.m. tomorrow. This shows the higher dew points just before the storm advances. This will lead to a much higher risk of severe weather events. Again, today is lacking, and tomorrow is just enough for a bad weather day. How much moisture will be available as the front moves through the night? This is a limiting factor for severe thunderstorms in our region.
There will be an area of development to the west later this afternoon and evening as you can see here.
In this map above, we show the developing surface cyclone. A low pressure center will strengthen near the Kansas-Nebraska border. A warm front will cross today and will be well north of Kansas City by 5 p.m. This will allow us to warm into the mid to upper 70s with high 80s just west of our region this afternoon. The area of thunderstorm development will be ahead of the dry line (the brown line with the semicircles). It will be well west of our region and that ensures it will be dry at least until sunset.
The cold front is expected to catch up with the dry line around 9 p.m., and that’s the most likely time for thunderstorms to start forming near that line.
On this next map, valid at 2 a.m., the cold front has taken precedence over the dry line. Thunderstorms on this model are not violent and quite weak. They’re stronger in Oklahoma.
Watch what’s expected to happen by midday Wednesday:
By noon Wednesday, the thunderstorms are not fueled by this slight push of higher humidity and the thunderstorms are intensifying.
Severe weather risks for tonight and Wednesday:
The risk increases significantly later tonight and Wednesday as the system crosses our region and encounters better conditions east and southeast of Kansas City.
What does all this mean?
- We’ll be monitoring the ingredients for severe thunderstorms to see if anything looks different by tonight. At this time, our risk of severe thunderstorms is low. Whenever we have thunderstorms we have to watch them closely and that is exactly what we will do. Low level humidity is an inhibiting ingredient at the moment, but other conditions are favorable for severe thunderstorms. If it were later in April or May there would be more moisture available, but it’s still early and this setup lacks that big ingredient.
- The timing of thunderstorms currently appears closer to midnight for Kansas City. We will closely monitor the development of the first thunderstorms later in the evening to see if that timing changes, but for now I think it will be after 10 p.m.
- The main risks for the development of severe thunderstorms will be larger hail and damaging winds. The risk of tornadoes is 2% within a 40 km radius of any location, which means there is a 98% chance there will be no tornadoes near you. which is a very low risk.
Kansas City forecast:
- Today: There will be a few periods of cloudiness mixed with sunshine. Temperatures will warm to nearly 77 degrees later in the day with winds blowing 35 miles per hour from the south. Keep your hats!
- This evening: There is a 70% chance of showers and thunderstorms between about 11 p.m. and 6 a.m. There is just a low risk of severe weather in your area. The wind will turn northwest and west in the morning. Moo: 52 degrees
- Wednesday and Thursday: There is a chance of rain showers and much colder weather with temperatures dropping into the 40s on Wednesday. There is a chance of a period of light snow Wednesday evening or early Thursday with no snowfall expected.
Thank you for sharing this weather experience and spending a few minutes of your day reading the weather blog. Have a great day and we’ll keep you posted on KSHB 41 news as this system gets closer.