What’s A Derecho And More Heat!

There are some VERY subtle changes in the weather around the region today. One is some of you are waking up to a few clouds this AM…and yes there were actually a couple(!) of showers that lasted about 30 minutes north of the metro. Both these events are signs that the ridge aloft, that’s been driving the heat has started to temporarily flatten (weaken) a bit. There is also frontal boundary located across the I-80 corridor, which unfortunately will be lifting northwards and washing out over the next few days. The flattening ridge also allows weak disturbances to pass across NE and IA generating storms that may drift across parts of N MO later today, mainly along and north of 36 Highway. So at least there is a chance that some may get some rainfall later today/this evening. The cap is also weaker across NC MO today, so that may help the cause just a bit. The latest NAM however is not to optimistic about much activity, so at this point I’d put the odds around 20% for far N MO.

As far as the “clouds” go, there are some out there north of the metro and they may tend to thicken up for a few hours before thinning as they move towards the ESE.

Regardless another day with highs around 100° is expected. This will also be the last day for a bit concerning the Excessive Heat Warning. With dewpoints in the lower 60s the air temperature and the dewpoint will not change the heat index that much.

It’s not that we’re expecting a “massive” cooldown over the next couple of days. I’m still expecting highs to be in the 95-100° range on Sunday and Monday, before the ridge tries to firm up again allowing highs to pop into the 100-105° range for the rest of the next workweek with continued dry weather. The ridge may then start to drift farther towards the Rockies later next weekend which would then help to reduce the heat somewhat and maybe even allow a weak front or two to come through. It is possible that we may get a break in the weather for the All Star festivities from Sunday through Tuesday…around the 10th or so.

Yesterday was a big severe weather day through the Ohio Valley and Mid Atlantic states. A large long-lived complex of storms developed and moved towards the ESE. The complex was able to sustain itself for a long period of time and became what is known as a derecho. First take a look at all the different severe weather reports generated by the complex.

Over 800 reports alone! Sadly this event was also a killer as 6 people died and more than 20 were injured.

The folks at the SPC have a lot of information about these types of events…but here is a better definition for you…

A derecho (pronounced similar to “deh-REY-cho” in English, or pronounced phonetically as ““) is a widespread, long-lived wind storm that is associated with a band of rapidly moving showers or thunderstorms. Although a derecho can produce destruction similar to that of tornadoes, the damage typically is directed in one direction along a relatively straight swath. As a result, the term “straight-line wind damage” sometimes is used to describe derecho damage. By definition, if the wind damage swath extends more than 240 miles (about 400 kilometers) and includes wind gusts of at least 58 mph (93 km/h) or greater along most of its length, then the event may be classified as a derecho.

Take a look what happened in Joliet, IL when the powerful winds hit a minor league complex when a tarp was on the baseball field.

Hundreds of thousands are without power in the wake of the storms. Here is another vantage from NE Ohio of the storms blasting in.

We certainly don’t want that, but the rain would really be welcome around these parts. From the NWS in Pleasant Hill…

If no precipitation falls through the end of June at Kansas City the 5.25 inches of rain that has fallen since April 1st would be the second driest April-May-June on record.

That’s not good heading towards the heart of summertime.

Have a great weekend. I may try and update the blog again tomorrow. I’m actually off till tomorrow evening so I’ll see you again on FOX 4 News @ 9/10 on Sunday night.

Joe