The first is for Louisiana and far southeast Texas. The Storm Prediction Center is working on a new watch for Mississippi that I will post as soon as it is available.

When it comes to tornado forecasts of this nature, 5% is the significant threshold (5% chance of tornado within 25 mi. of any given point). Fifteen percent is a very significant threat. Today's tornadoes, however, are likely to be relatively short-lived and difficult to warm of. In a situation like this, I recommend you keep your children nearby and be ready to move to shelter quickly if a warning is issued or  if a thunderstorm moves in and things "don't feel right." Yes, you read that last phrase correctly. There is certainly a role for common sense in situations like this.

At least one fatality has already occurred (in Arkansas) with tornadoes today. Please keep up with the latest weather information if you are in the tornado risk area (scroll down). ADDITION: 11:20am. Tornado risk in the Delta area is really increasing and will remain relatively high for at least the next couple of hours. Red polygons are tornado warnings. Memphis at upper right.

Here is the tornado risk for today and tonight. five percent is significant. There is also a risk of damaging winds. Fifteen percent is the significant threshold. The hatched area is where gusts of 75 mph or higher are forecast by the Storm Prediction Center.

According to the U.N. Framework Convention on Climate Change, preventing “dangerous human interference” with the climate is defined, rather arbitrarily, as limiting warming to no more than 2 degrees Celsius (3.6 degrees Fahrenheit) above preindustrial temperatures. The Earth’s surface temperatures have already warmed about 0.8 degrees Celsius since 1850-1900. This leaves 1.2 degrees Celsius (about 2.2 degrees Fahrenheit) to go... Nicholas Lewis and I have just published a  study  in Climate Dynamics that shows the best estimate for transient climate response is 1.33 degrees Celsius with a likely range of 1.05-1.80 degrees Celsius. Using an observation-based energy-balance approach, our calculations used the same data for the effects on the Earth’s energy balance of changes in greenhouse gases, aerosols and other drivers of climate change given by the IPCC’s latest report. We also estimated what the long-term warming from a doubling of carbon-dioxide concentrations would b...

The first watch has been issued, a severe thunderstorm watch for Oklahoma and small parts of Kansas and Texas until 11pm CDT. More, and stronger, thunderstorms are likely to develop over the next 36 hours. I will not be live-blogging these storms but will provide a few updates.

Some of you came to the blog this morning and saw that it had been deleted. That is a result of an attack. I know there are many people who upset at this blog's position on global warming but I have no way of knowing if that was the motive. If I were ever to close the blog, I would announce it in advance. There is a chance of severe thunderstorms and tornadoes to start this week. Just scroll down.