In the best of all worlds, Dolly would cause minimal damage, but also bring a maximum benefit to us in the form of rain. While the storm will likely make a landfall near Brownsville, the rainbands should spread northward along the coast, even as far north as Houston/Galveston. The model projection shown above indicates anywhere from 1 to 3 inches of rain could fall south of I-10 through mid-day Wednesday as Dolly approaches. Depending on how the rain falls, this might cause some local flooding in low-lying areas. So we'll have to monitor the storm as is gets closer to landfall sometime Wednesday. As far as winds, I don't expect annything more than a steady east wind startting tomorrow getting no higher than 15 to 20 mph. The wind will be stronger along the coast and we could see elevated tides. However, a significant storm surge is not expected here.

Tropical Depression #3 formed tonight off the South Carolina coast and will slowly drift up the East Coast and then out into the Atlantic by early next week. A depression isn't named and it's winds are below 39 mph. If however, the system strengthens, and it probably will, then this storm would get the name Cristobal.

Meanwhile, the storm we've been focusing on since the beginning of the week hasn't become a depression, yet.

It is encountering shear from low pressure just to it's norrth. However, it will likely strenghten as it continues through the Caribbean this weekend. The latest computer model projections show it crossing the Yucatan Peninsula by Monday and possibly heading toward South Texas.

Each time we run the computer models, they give a different track, so its important to stay informed throughout the weekend. Check in with Mario Gomez on 11 News this weekend and at Hurricane Central on khou.com.

The as yet undefined system in the Caribbean continues to track westward. Tonight's computer models show diverging opinion. The so called spaghetti plot above show where different models say the system will be over the next 5 days. Some models are based on history and some are based on the current environment around the storm. About half these models say the storm will "shoot the gap" between Cozumel and Cuba and enter the Gulf Of Mexico by early next week. The other half says the system will head toward Belize and then (if it holds together) enter the Bay of Campeche. Stay in touch with KHOU news, we'll track this system carefully and remember that since conditions change through the day, check the weathercast and khou.com as often as possible. If the storm does indeed enter the Gulf, it is way too early now to tell where it might end up. However, this is an early heads-up that we may be gearing up for something come Monday or even Sunday. The models, by the way, do not indicate that this system, if it enters the Gulf, will be a hurricane, just a moderate tropical storm. However, since Gulf waters are very warm (>85), anything can happen.

The drought classifications run like this: Dry, Moderate, Severe, Extreme and Exceptional. Across the official recording locations in southeast Texas, the breakdown is:

Notice that Pearland's Clover Field is showing a nearly 2" surplus for the year and Hobby Airport is only in a slight deficit of just under an inch. Recent heavy rains in those areas have helped. The problem is that our daily downpours were brief and widely scattered.

I have first-hand experience with drought conditions as I moved here from Georgia, which is still in the grip of a major drought that has lasted over a year. We had water restrictions; not just that you couldn't water on certain days, but you couldn't water at all. Hopefully, we'll see some relief soon, perhaps by Tuesday of next week. And then there's always a tropical system that could come and help us out. But you know the old saying, "be careful what you wish for..."

This is a "fire-rainbow", the rarest of rainbows, captured in Galveston by Dennis Stritz. Dennis is buddies with one of our KHOU photogs, Tom Empe and he called Tom all excited because he had seen this. Rainbows usually occur after it rains and it hadn't rained in Galveston today. However, this sky phenomenon occurred because of a precise alignment of the sun and ice crystals suspended in cirrus clouds, floating at 20,000 feet above the ground. Sometimes, we see the fire-rainbow's cousin, the sun dog. But it's usually only a sliver of a rainbow on either side of the sun. To see a long streak of color is rare and unusual. Typically, this sight is only seen in the northern plains.

For the period from 1975-1995, there were only two July hurricanes - Bob in 1979 and a different Bob in 1985. The names we use for hurricanes are repeated every six years and catastrophic storms are removed from the list replaced by new ones. Both Bobs were fairly benign storms. 1979 ended up with 8 total storms while 1985's tally for the year was 11.

However, the period from 1995-2008 contained 6 July hurricanes and the average storm total for the years with July hurricanes was 16! That is quite a dramatic difference and it points to the fact that we've been in an active hurricane cycle since 1995.

Whether Bertha means the rest of the year will be active remains to be seen, but if history is any indicator, we should brace for the worst.

The hurricane names are recycled every six years and it is interesting to note that Bertha was used in 2002 and 1996. In the latter year, it formed just a little west of this year's version and became a major hurricane that eventually struck the North Carolina coast:

It too formed in early July and was part of a series of storms that formed off the coast of Africa and eventually made the trek across the ocean to the Caribbean and the U.S.

Bertha is early in its journey and will likely turn up into the north Atlantic toward cooler water and weaken. Of course, we'll keep you posted.

Imagine looking out the window and seeing this every day? Well that's exactly what scientists who work at Boulder's National Center for Atmospheric Research (NCAR) see. I had the opportunity to tour this one-of-a-kind facility last week as part of the American Meteorological Society's (AMS) Broadcast Conference, which was held in Denver. Over two hundred broadcast meteorologists from around the country came to hear presentations and tour NCAR. We also toured the nearby National Oceanic and Atmospheric Administration (NOAA) labs. There, we learned about Space Weather and saw the NOAA facility dedicated to studying the sun:

Sunspots can have a significant influence in GPS and telecommunication systems and the Space Weather Group is constantly monitoring solar activity. We also saw a model of one of the geostationary weather satellites that provides us with the pictures we need to accurately forecast the weather:

One of the cool sights was this Weather Globe, which projects real-time or computer simulations on a globe. Three projectors are pointed at the globe; the images move, but the globe stays still. Nevertheless, it looks like the globe is moving. It's a great educational tool and some museums around the country have it, but not here in Houston.

One of the highlights of the conference was a panel discussion on global climate change.
These four have all studied various aspects of the issue and some have contributed to the Intergovernmental Panel on Climate Change (IPCC). The ground-breaking IPCC report concluded that global temperatures are rising due to human activity, namely the burning of fossil fuels. Not all scientists, however, agree on the magnitude of this and whether or not it will continue based on climate models. However, it was useful to hear the information. I taped several interviews with some of these scientists and one of them can be heard in it's entirely on the See On 11 News section of the khou.com website.

Pictured are (l-r): Prof. James O'Brien a Florida State Oceanographer, Dr. Kevin Trenberth, an NCAR scientist and IPCC author, Dr. Pieter Tans, an NOAA researcher specializing in carbon dioxide studies and Dr. Warren Washington, past AMS president and climate model researcher.

During the tour, we were momentarily distracted when someone sighted a large elk sitting calmly near a window. Even though we all huddled to get a better look, he never moved. The NCAR residents say wildlife is often seen roaming the campus. Apparently, they were there first.

Negative Lightning

A bolt of lightning usually begins when an invisible negatively-charged stepped leader stroke is sent out from a cloud. As it does so, a positively-charged streamer is sent up from the positively-charged ground. When the leader and the streamer meet, the electrical discharge takes place up the streamer into the cloud. The return stroke is the most luminous part of the strike and the part that is visible.
Most lightning strikes usually last about a quarter of a second. Sometimes, several strikes will travel up and down the same leader strike, causing a flickering effect. Thunder is caused when the discharge rapidly heats the air around the strike, causing a shock wave to be sent out.
This type of lightning is known as negative lightning due to the discharge of negative charge from the cloud and accounts for over 95% of all lightning.

Positive Lightning

This type of lightning represents less than 5% of all lightning. It occurs when the stepped leader forms at the positively-charged cloud tops, with the consequence that a positively-charged streamer issues from the ground. The overall effect is a discharge of positive charges to the ground.
Research carried out after the discovery of positive lightning in the 1970s showed that positive lightning bolts are typically six to ten times more powerful that negative bolts, last around ten times longer and can strike several miles distant from the clouds.
As a result of their power, positive lightning strikes are considered more dangerous. Positive lightning is now thought to be responsible for many forest fires and house fires during summer pulse thunderstorms.

This is the radar picture that clearly shows the "hook" echo from today's funnel cloud south of Houston. The red circle over Friendswood is a "shear marker" that shows how HD Doppler detects the rotation in the storm. The white dots are the lightning strikes occurring with the storm.

The storm emerged just south of Houston just after 6 pm and we tracked it with HD Doppler during the 6 pm news. Just at 6:30 pm, we received a report of a funnel cloud sighted near Beltway 8 and Highway 288, followed by another report of damage to a roof of a home and then a report of a mobile home damaged. Rita Schack took this picture from the Silverlake Subdivision in Pearland at that time: