File:KSC-05-S-00181 (ksc 071005 114 wx).webm

English: I'm here with Kathy Winters, launch weather officer. Kathy thanks for joining us. MS. WINTERS: Thanks. MS. STILSON: Kathy, Hurricane Dennis is obviously on everyone's mind. Let's start with some questions from our viewers. Erin, from Crystal Lakes, states, as I'm sure you know, Hurricane Dennis is spinning in the Atlantic. What do you feel is the possibility of the Shuttle launch being postponed or cancelled? If delayed, how long? MS. WINTERS: Well, that was a big concern for us when Hurricane Dennis was in the Atlantic. Now it's out in the Gulf of Mexico and, unfortunately, it's going to impact the northwest Panhandle of Florida as a Category 4 hurricane. But when it was in the Atlantic and heading in towards the Caribbean, we were very concerned and actually there was a point where the storm was actually starting to turn a little bit east of the track that it was originally forecast. And that had us concerned. But eventually we got comfortable that the storm was not going to be a threat and we were able to press on to launch. MS. STILSON: Steve from Georgia asks, when do you determine if a storm will postpone a launch, such as a hurricane in the Gulf of Mexico? MS. WINTERS: We determine it -- we look at a couple of things. We look at the peak wind speeds we expect to get at the pad, which if we think are going to exceed 70 knots of peak wind, then we would actually decide that we need to roll back the vehicle. But we also need to do that before we reach 40 knots of sustained winds peaking up to 60 knots. So that's more of a timing issue. We need to get back to the VAB, the Vehicle Assembly Building, with the Shuttle before we reach those winds because that's constraint to roll the vehicle back. So that's why we have to get it back before that time period. MS. STILSON: Well, besides the threat of hurricanes, Florida weather is already temperamental and unpredictable this time of year. We have to deal with rain, humidity, lightning. How can all this impact launch? MS. WINTERS: Well, in several ways. First, let's start with humidity. Humidity is an issue with tanking because it can have an effect on the ice on the External Tank. Humidity can actually be good on certain portions of the vehicle because it can actually moderate the temperatures on the outside of the External Tank. Also, with the rain and the lightning, we're always concerned about anything within ten nautical miles of the pad. We don't want to fly through any precipitation. And also, any cumulus clouds that may eventually develop into thunderstorms can also be an issue, even when they're early in their development due to the threat that we could actually cause the rocket to trigger lightning if we launch through certain types of clouds. So any clouds within ten nautical miles of launch pad will be evaluated for those type of concerns. MS. STILSON: That's very interesting. Most important question, though, how is the weather forecast shaping up for Discovery's launch? MS. WINTERS: Well, we're hopeful. It is summertime. It is July. And it's going to be in the afternoon, during the time we do see our thunderstorm activity. But we do expect the storms to be more inland. So our main concern will be, if we have any thunderstorms within 20 nautical miles of the Shuttle Landing Facility. So right now it looks like we have a 30-percent chance that KSC weather would prohibit launch. But that's a 70-percent chance of good weather. MS. STILSON: Right. Well, Kathy thanks for being with us today. Let's hope the weather cooperates for a great Return to Flight. MS. WINTERS: Definitely.