Wednesday Afternoon/Evening Severe Threat

Here we are almost to the Christmas holiday and I’m writing a blog post about severe weather and NOT snow! But with VERY warm temperatures expected Wednesday, along with the passing of a cold front, there is a low-end threat for isolated severe thunderstorms Wednesday afternoon and evening.

Here is what you need to know.

Set up To even see low chances for severe weather reaching up into Northwest Ohio for this time of year is pretty remarkable. Tuesdays outlook from the National Weather Service has West Central Ohio right on the northern edge of that low risk.

Outlook Wide

And a closer look

Outlook Close

The threat for severe weather will be present thanks to unusually warm temperatures in the mid 60’s along with the approach of a frontal system that will draw up a lot of moisture from the Gulf. This front and area of low pressure will have a lot of support from the jet stream which means very high wind shear will be in place, especially late afternoon and evening. The warm temperatures and high moisture will also allow for low but (still significant for this time of year) CAPE values that will allow for just enough instability to produce thunderstorms.  Here is a look at those CAPE values by about 2 PM Wednesday afternoon. They are definitely low, but really any CAPE this time of year is a bonus for potential severe weather.

CAPE

Notice in the picture above that the higher CAPE values are off to the west in Missouri and Southern Illinois. As the day progresses I’ll be watching to see if that area of higher instability can make it this far east. If it does, it appears the best chance for isolated severe storms will be late in the evening as the cold front nears West Central Ohio.

Timing- As of now the window for our storms appears to be between about 3 PM and 11 PM Wednesday. The threat for strong to severe storms will come in two waves, the first being with a prefrontal area of showers and thunderstorms that will take advantage of increasing moisture and temperatures already in the low to mid 60’s.

Prefrontal Activity

The second line of potential thunderstorms will move in between about 7 PM and 11 PM and it’s this line that I think has the better chance for isolated damaging winds, and to a much lesser extent, perhaps an isolated/brief tornado.

Local 2

Summary- My confidence in severe weather Wednesday isn’t very high. There will certainly be high wind shear in the atmosphere along with a small amount of CAPE, but I just have a hard time believing we’ll see much more than some isolated damaging winds this time of year. Between 3 and 11 PM on Wednesday my biggest concern is isolated winds from 50 to 60 mph and to a lesser extent the chance for a brief/isolated tornado.

Severe Outlook

I’ll be sure to keep you updated as the system moves in! In the meantime you can always track any incoming weather on our weather app!

New App

-Kyle

 

 

 

 

Advertisements

Omega Block Next Week Won’t Allow A Warm Up!

(Published 4/23/14)

If you’re hoping for a nice Spring warm up, you’re probably going to have to wait at least another week and a half thanks to a very typical spring pattern that is expected to set up.

As we venture into next week we will likely experience what is called a blocking pattern in the atmosphere or more specifically an “Omega Block”. When a blocking pattern sets up, depending on where you are, you can either experience a nice area of high pressure and sunshine for several days straight, or in our case a stubborn low that will bring rain and below average temperatures. When you look for signs of an Omega Block all you need to do is look at an analysis of the potential jet stream for next week. Check out this map, two areas of high pressure over the Atlantic and Pacific Oceans form what looks like the greek letter Omega. In between these areas of high pressure is an upper level low that will bring colder than average temperatures and the chance for rain all week-long.

Potential Location Of An Upper Low By Late Next Week

Potential Location Of An Upper Low By Late Next Week

These two areas of high pressure act like book ends that force the low to progress VERY slowly across the country. Simply put when you have a slow-moving low = cloudy, cooler and rainy weather.

As this low develops Saturday and begins to move at it’s turtle pace this upcoming weekend it will bring what could be the worst outbreak of severe weather so far in 2014. The upper low will drive a strong jet stream flow deep into the Southern Uniter States, these strong jet stream winds will interact with Gulf moisture over the midwest making for a potentially explosive severe weather situation.

Potential Jet Stream Flow Late Sunday

Potential Jet Stream Flow Late Sunday

With this set up expected, it’s no surprise that a multi day severe weather is being anticipated by The National Weather Service. Here is their Saturday (Red) Sunday ( Purple) and Monday (Green) severe weather outlook. This could likely include a widespread outbreak of tornadoes.

Areas Expected To Be Affected By Severe Weather Saturday, Sunday and Monday

Areas Expected To Be Affected By Severe Weather Saturday, Sunday and Monday

Thankfully, as of now it looks like as this system develops the best dynamics for severe weather will stay well South and West of us here in West Central Ohio. But it does look like we’ll have to deal with the other side of this slow-moving system which means a cooler, cloudy and rainy last week of April. I’ll keep you updated!

-Kyle