Severe Weather Targets the Mississippi Valley Today

There is a risk of severe weather this afternoon for states around the Mississippi Valley. This comes as a frontal boundary sags southward and a dry line is located out west.

This is a sounding valid for 18z tonight, known as 7 pm Central time. When you get the dashed line to the right of the soldi blue line, that is when you develop instability. As you can see, there is a large gap between the solid line and dashed line, indicating a lot of instability. CAPE shown on the sounding indicates over 3000 j/kg of instability present at that time.
Another thing seen on the sounding is something called 'ConvT', which appears to indicate the temperature when air will rise to produce thunderstorms. To figure out the surface temperature, I use 28 degrees Celsius, as the solid temperature line is in that 25-30 Celsius area closest to the bottom of the image. Converting 28 Celsius to Fahrenheit results in a temperature of 82.4 degrees F, a good 2 degrees above the ConvT of 80.4 F.
A couple final indices: The Hail index shows hail of 1.5 inches is possible. The hail index is the first parameter in the 4th column labeled 'Hail'. The Supercell Potential parameter, 3rd result in the 2nd column, indicates a 60% chance of a supercell if convection were to develop (which it will).

I don't blame you at all if you don't understand this- I just started getting the gist of it recently after a lot of researching and learning, so my apologies if I am confusing you.
In short, thunderstorms, with a fair chance of becoming supercells, are possible today.

-Andrew

2012-2013 Preliminary Winter Forecast

Hello everyone and here is the long-awaited 2012-2013 Preliminary Winter Forecast.
I have to say, I don't have too much information to share as a lot of pieces are too far out, so this is more of an examination of the ENSO conditions.

This past winter we were in a fake La Nina. It had a La Nina, but with El Nino weather conditions resulting. This summer, we are expected to have a neutral ENSO condition, and by this winter we may even have a slight El Nino. Here's a forecast for DJF (December, January, February) 2012-2013 off the Scripps ENSO Model.

The Scripps Model is forecasting a east-Based El Nino. There is indeed a difference between west based and east based. However, we won't dig into that because it is too far out to tell at this point.
Here's the average precipitation and temperature (respectively) results from weak El Ninos.

A weak El Nino typically brings slightly below average temperatures to the country, while bringing more precipitation to the East Coast and below normal rainfall for the Southeast.

Because it is so far out and I don't have too much to work with, here is what I will say:
•Weak El Nino likely
•Probably more precipitation for the East Coast

-Andrew