Welcome to Tuesday.
I trust today will be a little quieter :-)
A word about the storm reports from Sunday and yesterday's events. Lots of thunderstorms and downpours visited the region, and most folks made it through relatively unscathed. In a line from Maggofin County, KY through Lawrence Co., and on into southern Wayne County in WV they were visited by a severe thunderstorm on Sunday evening.
Harold Sloane with Emergency Management took this particular picture showing many downed trees in the same area. You can also see many shards of leaves plastered against the side of the trailer there in the picture. This would be a tell-tale sign of hail (breaking the leaves) and high winds (doing the plastering). This picture was taken in Ulysses, KY but down the road a few miles there was confirmation of a minimal tornado (EF-0) in the town of Lowmansville. It had winds of "only" 75mph or so, and lasted for a short distance. Here's the complete report on it if you want to read up on it. I have a few things to say about this particular storm. This one is a much better example of the average tornado we get around here in the tri-state, as opposed to the huge monsters we received in March of 2012. Not to say that it's a push-over by any stretch... just that most of the time tornadoes can go undetected until the next day due to their relative weakness. In fact, the straight-line wind damage seen toward Ulysses was probably from the same storm and about the same speed as the strength of the tornado. So the only difference is whether the wind was rotating or not-- which really isn't much of a difference. It's a good example of how not to only worry about tornadoes and slough off the straight-line winds that can accompany severe weather.
Okay... so now we're finally in a little bit of a break. The lingering moisture from the overnight is passing east this morning, and breaking clouds set in once again (this time not triggering any afternoon storms).
|HPC - Surface Map - Tuesday Afternoon|
As high pressure sends our storm system out to the New England coastline, warmer air rides in as well. Highs on Tuesday get back to the 80s, and the 90-degree mark is in range on Wednesday. The only limiting factor is the likelihood of pop-up showers and storms expected to form in the sector of the next approaching system where I put the green box. This is a typical summertime set-up, another one of which I want to make a few comments.
|GFS - 500mb Chart - Wednesday Afternoon|
From the map, an explanation of the numbers...
1. A heat ridge over the Southern Plains - We'll be seeing a lot of this during the summer-time. On a 500mb chart like this, a good rule of thumb is lopping off the "5" on the three-digit number contours, and you'll have a good ballpark value for high temperatures. In this case, the 588, or 88-degree line cuts across Kentucky. This ridge supplies ample heat energy for any triggers that may be wandering around.
2. Storm instigators - These are actually lobes of positive vorticity, and further, the forward side of those red blobs is where the instigation occurs (where the change in relative vorticity as it advances on a location is a positive value)...But we can stick with things like "blobs" and "instigators" ;-) Anyway, these babies often ride along the heat ridge border, tap into that storm energy, and feed it all the way across. They can easily organize into a complex of thunderstorms that persist for hours (and are trackable as such). Sometimes this means something called a 'mesoscale convective system', and other times they can be 'derechoes', etc. etc. ...
Now, Accuweather has already come out and thrown around the "D" word. I don't like this one bit, because even though technically such a set up is possible, the viewing public around here still has a special understanding associated with that phrase and it must be respected. What I mean is, when people hear about a 'derecho', all their going to picture is what devastated the region late last June and freak out. Yes, derechoes are nasty things, but the one we had a year ago may well have been the worst one in US recorded weather history. The thing about derechoes is that they have to cause an above-threshhold amount of damage across a long distance, which means we can track it and see it coming unless it actually starts locally (which is highly unlikely). Therefore we can hold off on using the word until we can offer it's proper intensity qualifier when seeing the kind of damage it is doing upstream-- if one indeed forms at all. Throwing it out there ahead of time, particularly around these parts, may cause undue worry and panic and I think there are ways to be appropriate about it while minimizing viewer freak-out (which is what I like to do). However, if I see a derecho signal on the maps heading this way... I will be saying so as soon as I know.
Anyway, the window for this to happen stretches from Wednesday afternoon through early Thursday, with nice and summery weather out there before-hand. Since the high temperatures are fighting to hit 90, and not crossing 105 like we had with last year's derecho, we already know there isn't as much energy out there for the taking. Nevertheless, it is a cause for concern, as the Storm Prediction Center has already pegged a similar region as I have for monitoring over the next couple days.
|SPC - Severe Weather Probabilities - Wednesday AM to Thursday AM|
Currently qualifying as a "slight risk" and focused closer to I-70 than our neck of the woods, it's not as dicey a situation yet compared to what we saw a little over a year ago. However, it's important to bear in mind that if we do get an MCS or a Derecho out of this juice, they often favor chowing down on the southern edge energy and will create a curl that may put such a thing on a trajectory towards us rather than up and over us. Regardless, it is something to watch. At least the temperatures are 15-20 degrees cooler than the kind of extreme heat that was in our area late last June.
|Regional Radar/Satellite with Warnings Tracking||
From the Storm Prediction Center (below): Click For a Larger Image
|Activity Overview||Storm Outlook||Watches||Potential Watches||Storm Reports|
|Temperatures||HD Doppler Radar||Estimated Rainfall||Active Warnings|
|Click For Larger||Click For Interactive Radar||Click For Larger||Click For Larger|
Have a great day everyone!