Friday, August 24, 2007; 2:00 PM
Ken Reeves, senior meteorologist and director of forecasting operations at
A transcript follows.
Ken Reeves: Welcome! Currently, much of the heavy thunderstorm activity is across Kansas and Oklahoma but a severe thunderstorm watch was just issued within the past couple of minutes for Missouri and parts of Illinois. It is going to be another nasty afternoon in the midsection of the nation. Feel free to ask your weather questions.
Washington, D.C.: How much longer do you predict this unstable weather will be around?
Ken Reeves: Through the Midwest, the worst will end today in terms of thunderstorms. Some of the strong thunderstorms can find their way eastward tomorrow into portions of New York state, Pennsylvania and Ohio
Fairfax, Va.: Can you explain, in layman's terms, how this confluence of weather systems happens?
Ken Reeves: Yes. You need moist air at low levels of the atmosphere because the increased water in the air makes it want to rise. You need something called instability. What that is is a temperature difference from the surface to higher portions of the atmosphere that is dramatic enough that the colder air aloft wants to sink and the warm air at the surface wants to rise. The rising motion of the air causes the water vapor in the air to condense into clouds and the drops get big enough to eventually fall in the form of rain. There are other ingredients that are more subtle that explain why storms produce lots of rain, hail, tornados or strong winds
McLean, Va.: Findlay seemed particularly bad off, saw the pictures on the news last night. What's the situation there today?
Ken Reeves: Currently it is hot and humid with temperatures near 90 and dew point of 72. There are no storms around now but some are possible later....and they don't need any more rain!
Annapolis, Md.: How many deaths out in the Midwest due to this weather? Is what's been happening a normal thing for this time of year? Is there anything that can be done about it?
Ken Reeves: Flooding and lightning are numbers one and two in weather- related deaths most years. I don't think anyone has totaled the numbers so far this season but no matter how much education is done to prevent the deaths, they seem to occur each year. There is a new field within meteorology which is studying how people react to weather information to increase effectiveness of warnings. Remember, while 80 percent of New Orleans evacuated before Katrina, 20 percent would not or could not. That is 20,000 people that were in the way of that storm
Washington, D.C.: I heard that in Iowa they were keeping a close eye on the Des Moines River and in Fort Dodge, crews were scrambling to shore up a levee. What's the status at those locations?
Ken Reeves: Unfortunately, the rivers have not crested in these areas yet and many of the cities and rivers are under flood warnings. I have not heard anything about the levee specifically but we know the damage that can be caused when levees are breeched....Katrina in New Orleans.
Glover Park, Washington, D.C.: Will D.C. be affected by all of this?
Ken Reeves: The flooding is not likely to affect the D.C. area but some of the storms could head eastward reaching the area Saturday night or Sunday.
Chantilly, Va.: Does everybody keep asking you if it's global warming causing this?
Ken Reeves: At AccuWeather.com, we get asked frequently about whether localized events are a sign of global warming. Despite what you may be told through the media, there still is a lot to learn about the global warming issue. We advocate continued discussion to get to the answers. It seems like the globe is in a warmer phase...at one point, there were glaciers in Pennsylvania and there are none now....but using one event in an extremely small portion of the globe seems to validate the existence of global warming seems to be a reach. It probably is happening and humans may have an as-of-yet undetermined role. The short answer to your questions is yes!
Washington, D.C.: I heard that someone was electrocuted. How did that happen? And what advice would you give to people in their homes when severe weather like this happens? What are five steps that you would suggest they adhere to? And what if power goes off and they can't get TV? How do they get advisories?
Ken Reeves: Wow...quite a few questions here. Let's peel them off one at a time. You did not say exactly how the electrocution may have happened. It could have been from lightning or a secondary source such as a downed power line or a power surge through existing wiring. Being in a structure with pipes and wiring is probably the safest place during a thunderstorm. The electricity, if it hits the house, can be channeled through the pipes and wires into the ground. Unfortunately, it can also damage electronic equipment. Stay away from windows and plumbing. Keep in mind that current can also flow through telephone wires. Television is not usually the best method of getting information quickly. Warnings are distributed through Web sites like AccuWeather.com and you get them faster than the television person can tell you. Your cellphone is a source of weather information as well. We have information available for all carriers. If you happen to have a NOAA weather radio, you can get information there as well. Many of the devices I mentioned work off of batteries. That is the best situation
Greenbelt, Md.: You mentioned New Orleans. In your estimation, could another Katrina happen there again? Have they rebuilt things better? What is the status down there?
Ken Reeves: Anything done in that area is really just a band-aid approach. The basic facts don't change. New Orleans is below sea level and can be hit by vicious hurricanes. Yes, you can build levees higher and better but the city sits in a bathtub and requires the removal of rainwater even without worrying about storm surge. Putting people back where they were evacuated from without making major changes is just exposing those residents again. It is not a matter of if but when it will happen again. The recovery is slow and many are not returning. It might make more sense to relocate parts of the city but that does not seem to be politically acceptable at this point.
Dec. 2004 Tsunami/Earthquake: The earthquake that caused the tsunami changed the earth's axis by a few inches.
Can that have a result on global weather?
Ken Reeves: There have been a number of examples in the history of the Earth that scientists have linked a major geological event to subsequent climate change. These range from volcanoes to meteor impacts. This could happen by ejecting materials into the atmosphere or changing the speed of rotation or tilt of the Earth. It is unlikely that the event in December 2004 had a significant, measurable change in global weather.
Washington, D.C.: Are the areas affected low-lying? Someone died of carbon monoxide poisoning. How'd that happen?
Ken Reeves: Most areas that flood are low-lying but you have to keep in mind that low-lying is relative to surrounding areas. As for CO poisoning, during weather emergencies, the most likely cause is improper use of generators. The generator provides electricity when the commercial power is out. The unit must be in a well ventilated area and not inside. Not even in a garage with the door open. The gas can be easily trapped and you are overcome before you know what happens. Once you pass out, unless someone else comes along to help you, death is a distinct possibility.
Ken Reeves: Well the hour flew by. I enjoyed all of your questions and keep coming back to washingtonpost.com for more interesting topics as well as the AccuWeather forecast. When the weather is in the news, you may very well hear from me again. Have a great, safe weekend!
Expert Senior Meteorologist and Director, Forecasting Operations
Editor's Note: washingtonpost.com moderators retain editorial control over Discussions and choose the most relevant questions for guests and hosts; guests and hosts can decline to answer questions. washingtonpost.com is not responsible for any content posted by third parties.