An August for the Record Books

There's no surprise August was an extremely hot month. But would you believe over 56 records were set this month? That's an astounding number of broken records. In fact, so odd, the National Weather Service office in Blacksburg compiled and released a list of August heat facts. Here's a summary.

+August 2007 will be the hottest on record for Roanoke, Blacksburg, Danville & Bluefield

+Over 56 records have been set for both high maximum and high minimum temperatures combined. (High minimum is considered the warmest low temperature for that date).

+There were numerous days 90+ degrees. Here's the breakdown by city: ROANOKE: 23 days
LYNCHBUG: 16 days
BLACKSBURG: 11 days
DANVILLE: 24 days

Total Lunar Eclipse

As the moon passed through the earth's shadow early this morning, few locally were able to see it. Clouds obstructed the view of the year's second Total Lunar Eclipse. For those that didn't get to see it, here's a look at the total eclipse that took place March 3rd of this year.



Aside from the clouds, a couple things got in the way of making this a spectacular viewing. The eclipse took place a bit too close to moonset OR sunrise (however you look at it). So, by the time the moon became totally immersed in the moon's shadow, the morning twilight interfered with its visibility. Also, the moon blended in with the clouds and haze we had in the atmosphere.

If you weren't able to see it this time, perhaps try next year. The next Total Lunar Eclipse will be February 20, 2008.

Meteorologist Brent Watts

Gustnado vs Tornado

Tuesday's severe storms that rolled through parts of the region created swirls of debris that appeared to resemble a tornado. Several folks reported seeing a funnel cloud. However, many weather features can create a tornado-like swirl. One of those is the gustnado.
A gustnado is a short-lived swirl of wind (whirlwind) that develops on a thunderstorm outflow boundary called a gust front.


Gustnados develop from the ground up as winds interact with land and begin to swirl, picking up dust and debris. The result is similar to a small tornado. However, if you're brave enough to look closely, you'll see the gustnado is not attached to the cumulonimbus cloud or related to the storms rotation, unlike its cousin the tornado.

It CAN produce damage due to its straight-line winds that can reach over 70mph. Gustnado damage is typically limited to small trees, windows and tossing around of loose objects, but can be worse in a very strong storm.

Thankfully, we're not accustomed to seeing these acts of nature in these parts very often. So, being able to differentiate between the two while finding shelter is fairly difficult. Regardless of the culprit, wind damage was reported and the daily plans were disrupted for a short period of time. Had this been a strong tornado, this may be a different story.

Send your weather questions to: bwatts@wdbj7.com

--Meteorologist Brent Watts

Space Station and Shuttle

Mark Hodges from the Science Museum of Western Virginia sent us this cool photo of the International Space Station and Shuttle Endeavor.

In his email he writes: "I shot this this evening at 9:30pm from the 5th floor parking deck at Center in the Square passing over the Hometown Bank building. The Space Station is first with the shuttle just passing over the top of the building."

This photo was time-lapsed and is very good considering the amount of ambient light in Downtown Roanoke at night.

The image was taken just in time, as Endeavor will be returning to earth this afternoon, a day earlier than expected. Staff at mission control in Houston was concerned that Hurricane Dean might impact the weather there, causing communication issued between the shuttle and ground staff.

Today's landing of endeavor will take place around noon in Florida. Endeavour's first landing path would take the crew over the Pacific Ocean, Central America and Cuba before touching down at Cape Canaveral in Florida.

If bad weather forces NASA to scrub that landing attempt, the shuttle's second opportunity would include flying over Mexico's Yucatan Peninsula, which was battered Tuesday morning by Hurricane Dean. If the shuttle crosses above the hurricane, it will be too high to feel its effects, according to NASA.

Pretty interesting. As always, thanks for the photo Mark.

--Brent

Mean Dean Gets Meaner

It was a phrase I jokingly used on the air last week. "Mean Dean." At the time, Dean was merely a cluster of storms that had reached tropical storm status. We had already seen three of those this season with little major impact. Dean however is certainly different.

As of this blog entry, Hurricane Dean, a Category 4 with winds topping 150mph, has already devistated parts of the Caribbean Islands, completely wiping out precious banana crops in St. Lucia and Martinique.

The dangerous hurricane is being guided by a low pressure system that was over southern Florida. That low has now taken a westerly move and will be replaced by a ridge of high pressure over the east. This should keep Dean on a southerly route through the Yucatan, and into the southern Gulf of Mexico. Most of the models have the northern Gulf "in the clear." This spaghetti plot (below) that meteorologists look at as forecast guidance, takes all the various computer model runs and compares the forecast track. The one on the left shows most of the models are now coming together on a southern Gulf route to Dean, which takes him either into southern Texas or northern Mexico.

As a result of a possible Texas landfall. NASA has decided to bring the space shuttle home early for fear mission control in Houston could be disrupted. The photo on the right was taken from the shuttle. It shows Hurricane Dean with the Space station in the foreground.

With several thousand oil rigs in the Gulf of Mexico, even without a US landfall, we will likely feel the impact in a gas price increase. A simple trade-off for being spared so much devistation. We'll continue to monitor Dean. You can too in our Hurricane Center section. You can find it by returning to the main weather page and click on the hurricane center icon.

So long for now! --Brent

Heat, Humidity and Water Woes

"It's not the heat, but the humidity." We hear it all the time. But we are living that phrase this week. Last week, air temperatures reached 100 and dew points (measure of amount of moisture in the air) were extremely high (60s & 70s), which made it feel like a sauna each time you stepped outdoors.

This heat wave is different in that our moisture source is cut-off, so our air is very dry, almost like the desert. At one point Wednesday, the dew point was 49 and the relative humidity was 27%. That's almost as dry as Death Valley.

We're in desperate need of rain. Roanoke Regional Airport has a deficit of -7.98" for 2007. In the middle of a moderate drought, Danville is even worse, down -8.15" for the year. It's not unusual that summer is dry, with mainly scattered storms being the main source of precipitation. We typically see a return of wetter weather in the fall as the tropics get active and also when the jet stream returns a bit farther south. One could only hope we can make up for some of the lack of rain as we did at the end of 2006.

Below is the temperature and precipitation outlooks for September-November, based on climate and current models. This data comes from NOAA and the National Weather Service.

THE TEMPERATURE OUTLOOK FOR SEPTEMBER-OCTOBER-NOVEMBER 2007 CALLS FOR ABOVE NORMAL TEMPERATURES OVER MOST OF THE UNITED STATES. THE CHANCES OF ABOVE NORMAL TEMPERATURES ARE SOMEWHAT HIGHER THAN NORMAL FOR THE SOUTHWEST DUE LARGELY TO THE LONG-TERM TRENDS AND ONGOING DROUGHT CONDITIONS.

ABOVE NORMAL PRECIPITATION IS EXPECTED ALONG THE GULF AND ATLANTIC COASTS PARTLY DUE TO AN EXPECTED ACTIVE TROPICAL ATLANTIC STORM SEASON AND ALSO DUE TO THE LONG-TERM TRENDS.

What does this all mean? Conserve water, drink water, and pray for water. --Brent

Waterspout Photos

Our weather intern David Wolters just came back from a Florida vacation. Aside from the vacation stories of wild parties, surf and sand (OK, at least 2 out of 3), he shared some of the coolest photos he took while there.

Florida is known for its abundance of storms. Over land they can produce tornadoes. But over water, those same formations are called waterspouts. Here are some of the photos he took. He would estimate the spout was about 10 miles from land. Luckily, it stayed there. Thanks for the photos. --Brent

Supercell Storms

We've certainly had our share of stormy weather over the past several weeks. A fellow employee (thanks Debra) sent me this video of a supercell storm time lapse from Oklahoma.

You might define a supercell as a thunderstorm with a deep rotating updraft (mesocyclone). In fact, the major difference between supercell and multicell storms is the element of rotation in supercells. As you will see in the video below, these storms do have quite the rotation, and if conditions are right, can produce tornadoes.

Learn more about supercells here...after watching the video :) --Brent