Updates Below (most recent 10:00am)
Good Tuesday morning to you!
The forecast from yesterday so far is on track... so lets take a look at the models for Today to evaluate the different wrinkle that today brings. Here's the NAM model:
|NAM - Tuesday Morning|
It's pretty patchy when considering the entire tri-state area, but there will be a spot or two with better Doppler returns. However, the models are not handling the situation very well, because there are a bunch of things going on aloft that need our consideration.
First, lets look at the winds at the different levels of the atmosphere:
|NAM - Winds - Tuesday PM|
The closest to the surface is the lowest map, and by the top map (700mb) is about 10,000 feet. What you see is that the winds are ratched up pretty swiftly from the low to mid level of the clouds. Put another way, here's how the winds will appear over-head, particularly in Eastern Kentucky:
Just like shoving an oar into the water when canoeing, the fast moving water right at the point of impact interacts with the slower water a little ways away. Eddies are created because of the difference in fluid flow. The same thing occurs in the atmosphere, and this shear, when consistent and prolonged can cause problems if a thunderstorm complex is able to hook up to this turbulence.
Here's a few model products to consider for this afternoon:
|NAM - Shear - Tuesday PM||NAM - Available Storm Energy - Tuesday PM|
The shear gets pretty steep Tuesday afternoon in sections of Kentucky and Ohio. It is also linked up to a (very marginal) area of storm energy in the same location. To mean, it seems like an event that has a low likelihood of happening, but because of that high shear value, any thunderstorm that does kick-up in that location has the possibility of morphing into a severe storm, isolated and/or compact as they may be.
The Storm Prediction Center had been thinking similar things for today, and here's their rendering:
A "slight" outlook category is minimal as far as true 'alert' situations go. It's more of an FYI in case the outside shot of such a storm materializes. In fact, if you look again at the NAM model image of shower coverage, not as many line up with the same region of high shear. This should not be taken as Gospel though, as it's usually a good idea to get a general sense of the precipitation profile from such model products, rather than a dead-set deterministic "this time at this place" read on where the weather will be. Anyway, in my opinion, I've been more concerned about severe weather prospects with other situations...but I thought it important to pass along the information, as well as offer a little insight into wind shear. If you have any further or questions on this, please ask away in the comments section :-)
The forecasted "dry slot" conditions we talked about yesterday are still on-course for Wednesday, as well as the generally pleasant weather for Thursday. The weekend storm system still bears watching, if for no other reason than it's still projected to drop in the coolest weather thus far this season (which is reasonable considering we're headed toward winter-- might as well, right?)
|GFS - Sunday Afternoon|
That thick black line represents the freezing-point (32F) at the 850mb level (about 5,000 feet above ground). We will be struggling to get out of the 50s by then, but the more interesting weather will be along the lake shores, where I would not be surprised to see some flakes flying.
Update (10:00am) - The Storm Prediction Center has reduced its forecast for today in terms of severe weather threat. No areas are under a "Slight Risk" any longer, though that will not completely eliminate a threat. See the maps below for more details. As detailed above in my analysis, I would concur with this downplayed perspective. We'll certainly continue to track things during the day, as you can too, right here.
|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!