Google Search

For weather information from across the nation, please check out our home site National Weather Outlook. Thanks!

Washington DC Current Conditions

Washington DC Weather Forecast

Washington DC 7 Day Weather Forecast

Washington DC Metro Weather Radar

Showing posts with label lightning. Show all posts
Showing posts with label lightning. Show all posts

Wednesday, February 11, 2015

Sudden jump in a storm's lightning might warn a supercell is forming

A sudden jump in the number of lightning strikes inside a garden-variety thunderstorm might soon give forecasters a new tool for predicting severe weather and issuing timely warnings, according to research at The University of Alabama in Huntsville (UAH).

The sudden increase in lightning is one sign a normal storm is rapidly evolving into a supercell, with a large rotating updraft -- or mesocyclone -- at its heart.

"Supercells are more prone to produce severe weather events, including damaging straight line winds and large hail," said Sarah Stough, a UAH graduate student in atmospheric science. "Supercells also produce the strongest and most deadly tornadoes."

Early results from Stough's research were presented Jan. 7 in Phoenix at the American Meteorological Society's annual meeting.

"Roughly 90 percent of mesocyclones are related to severe weather of some kind, while only 25 percent are associated with tornadoes," Stough said.

Because the sudden increase in lightning strikes is either concurrent with -- or within minutes of -- a supercell forming, UAH researchers are developing algorithms that might be used by forecasters to issue timely severe weather warnings.

"Basically, we keep a 10-minute running average of the number of lightning flashes in a cell," Stough said. "Then, if the flash rate suddenly jumps to at least twice the standard deviation of that running average, there is a high probability the updraft in that cell has strengthened, a supercell is forming and severe weather is more likely with that storm."

"We can use the lightning jump as a nowcasting tool for supercells if the jump is set in the context of that storm's environmental data," said Dr. Larry Carey, a UAH associate professor in atmospheric science. "If the meteorology of the day suggests supercells are likely, the jump can tell us when and where that is happening. Early warning of supercells -- especially the first of a severe weather day -- is an important forecasting challenge."

The lightning jump has been tested as a forecast tool by National Weather Service forecasters in Huntsville, Ala., and at NWS testing facilities in Norman, Okla.

"I know a lot of forecasters are excited about having this information," Stough said.

While the ongoing research uses ground-based lightning detection networks, the UAH team is also working on being able to use lightning counts reported by the Geostationary Lightning Mapper aboard the GOES-R geostationary weather satellite, which is scheduled to launch in 2016.

"The lightning jump is getting in front of forecasters now so we can get feedback, and fit the lightning jump concept into their forecasting methods," said Chris Schultz, an atmospheric science graduate student at UAH and an intern at NASA's Marshall Space Flight Center. "This way, when the real-time data from GLM is available and the lightning jump is implemented, it will immediately fit into the forecasters' warning operations."


View the original article here

Sunday, May 11, 2014

System to calculate lightning under development

Huge numbers of people who work or play outdoors might eventually soon possess a new tool to assist them to prevent being struck by lightning.

Based on a 2-year research grant from NASA, researchers on your lawn System Science Center in the College of Alabama in Huntsville are mixing data from weather satellites with Doppler radar and statistical models inside a system that may warn which specific pop-up storm clouds will probably produce lightning so when that lightning will probably begin and finish.

"Our major goals would be to boost the lead time that forecasters have for predicting which clouds are likely to create lightning so when lightning will begin,Inch stated Dr. John Mecikalski, among the project company directors as well as an connect professor in UAH's Atmospheric Science Department. "When we can mix data from satellites, radar and models right into a single lightning forecast system, we are able to provide the National Weather Service along with other meteorologists a brand new tool to aid predictions."

Additionally to operate done at UAH and NASA, the brand new lightning nowcasting project uses information produced by scientists at a number of institutions, Dr. Mecikalski stated. "Many of the research in lightning conjecture continues to be done, but weather service forecasters weren't obtaining the take advantage of that actually work. For example, you will find still limited radar-based lightning forecast tools open to forecasters despite everything which has been completed in that area."

While there's no operational lightning forecast system using radar, scientists while using existing Doppler weather radar system could possibly get lightning forecasts right about 90 % of times, he stated, but could only give in regards to a ten to fifteen minute lead time.

Using cloud data from NOAA's GOES weather satellites, they wishes to boost the warning time up to 30-45 minutes before a storm's first lightning expensive, although individuals predictions may be somewhat less accurate.

By merging the satellite and radar systems with statistical models, the UAH team wishes to create an finish-to-finish lightning forecast system that may track bad weather cell and it is lightning in the first indications of rapid cloud growth completely through its collapse, supplying lightning predictions that rise in confidence like a cell evolves from cloud to towering cumulus to thunderstorm.

The brand new lightning conjecture system may also be coupled with UAH's "nowcast" storm predicting system, that is available on the web at nsstc.uah.edu/SATCAST. The SATCAST system uses cloud top temperature data collected by instruments on NOAA satellites to calculate which pop-up clouds will probably produce rain, so when that rain will probably start.

Throughout the system's early development, the UAH team uses data from storms in Florida (certainly one of North America's lightning locations) and North Alabama to check the best way to mix the 3 teams of operational data right into a real-time conjecture system, stated Dr. Ray Carey, another project co-director as well as an connect professor of atmospheric science at UAH.

When the concept is proven and also the product is working within the test areas, they intends to expand its coverage region by region over the U.S., modifying for that unique storm dynamics of every region, like the High Flatlands.

Additionally to presenting cloud top temperature data available through existing weather satellites, the brand new lightning forecast system may also be involving lightning expensive information collected through the Geostationary Lightning Mapper, an optical instrument slated to become released aboard generation x of NOAA weather satellites in 2016.

Capable of seeing, pinpoint and count almost all lightning flashes on the large area of the globe, the GLM instrument will let forecasters track a person storm's lightning profile, which coupled with other data might be employed to help forecasters problem an exciting-obvious whenever a storm has stopped triggering lightning flashes.

Throughout yesteryear 3 decades, lightning has wiped out about 50 individuals the U.S. every year, which makes it the nation's third-most standard reason for weather-related deaths (behind surges and tornadoes) throughout that point. It's believed that lightning also injures about 500 individuals the U.S. every year, although a lot of lightning injuries go unreported.

Worldwide, it's been believed that within an average year lightning will kill about 24,000 people while hurting another 240,000.

While forecasters would be the primary audience likely to make use of the new lightning nowcast system, the system's designers hope the internet predictions of impending rain and lightning will also have value for individuals involved with outside activities, for example construction, farming and coordinators of outside occasions.


View the original article here

Thursday, January 17, 2013

Record Low Lightning Deaths in 2011; What about 2012?

A horrific weather year. I'm sure that you are aware of how bad 2011 was overall in terms of severe weather, with more than a dozen billion-dollar weather disasters and a record 99 Presidential disaster declarations. With 552 tornado fatalities, the year tied with 1936 for second-most tornado deaths on record, trailing only 1925 which had 794. April alone brought 748 tornadoes, a record for any month of any year. May brought the tornado at Joplin, Missouri that killed at least 158 people (with additional indirect deaths), most for a single tornado in the United States since 1947.

The listing of severe events could go on and on! You can refresh your memory about 2011 in Stu Ostro's blog and images of 2011 and my blog on the 2011 tornadoes.

Record-low lightning fatalities. Despite all of the severe thunderstorm and tornado activity, there were only 26 confirmed lightning fatalities in 2011, a record low. While this is still too many, it's gratifying that the trend has been downward for decades. We've been helping spread the message "when thunder roars, go (stay) indoors" and hopefully that has been a contributing factor. (Read more about this slogan below.) The safest places to be are inside a building with plumbing and wiring or inside a metal-bodied and metal-roofed vehicle. Keep away from electrical appliances, corded telephones, and plumbing during a thunderstorm, as lightning can travel into and through the house in wires and pipes. Avoid contact with metal inside vehicles. Stay in these safe places for at least 30 minutes after the last thunder or lightning has ended to allow storm clouds to clear the area.

Practice lightning safety in 2012. Even one lightning death is too many, and about 10 times as many people are injured as are killed. Most of the casualties are people caught outside during a thunderstorm. Monitor the weather and avoid outside activities as much as possible when thunderstorms are predicted, particularly activities in remote areas where a shelter would not be within quick reach. Many of the fatalities are from the first strike of a thunderstorm. Thus, it's best to seek shelter when the skies start to darken on a day when thunderstorms are predicted. Certainly practice another safety rule "Use your brain, don't wait for the rain!" And don't let sports activities delay your response. Remember more lightning safety slogans: "Don't be lame, end the game! Don't be a fool, get out of the pool!"

Miss America Contestant a Lightning Safety Spokesperson. Lightning safety advocates will be rooting for Ellen Bryan, Miss Ohio (right above) to win the Miss America Pageant on 14 January. She has been a
spokesperson for lightning safety for several years. Her sister Christina (left above) was struck by lightning in 2000 and suffered permanent brain damage. Ellen has made lightning safety and "when thunder roars, go indoors" her Miss America platform issue. You can read Christina's story and watch their lightning safety video clips at the link above.

What about 2012? About this time each year, people wonder how bad the new year will be. In reality, the skill in predicting that is quite low. When it comes to anticipating tornadoes, many researchers have examined potential links to El Nino and La Nina. Results have varied depending upon geographical region and how the studies were conducted. Results are a bit more robust for tropical cyclones, with El Nino conditions tending to reduce the threat of tropical cyclones for the United States. The current La Nina conditions are predicted to persist at least into the spring, and if they persisted beyond that then there would not be a suppressing factor for at least the start of the tropical cyclone season.

El Nino is a phenomenon in which surface and near-surface waters in the eastern and central portions of the equatorial Pacific Ocean are warmer than average. By contrast, La Nina episodes have below-average water temperatures there. The warm or cold waters can impact the formation and location of thunderstorm clusters and rising motions in these areas that, in turn, can affect the strength and location of the jet stream in subtropical and middle latitudes. The jet stream influences weather systems that sometimes produce tornadoes.

There has been a tendency for large tornado outbreaks during La Nina episodes during the January through April months. The record numbers of tornadoes in each of those months occurred during La Nina conditions, including April 2011. Of the eleven largest and most impactful tornado outbreaks since 1950 in those months, six were during La Nina, 3 during El Nino, and 2 during neutral conditions. These statistics suggest, but don't guarantee, above-average tornado activity in January-April 2012. Historically this activity occurs mainly in the Gulf Coast (excluding the Florida Peninsula), Southeast, Mississippi Valley, and Tennessee Valley states.

El Nino conditions have tended to exist during large tornado outbreaks from May through December in the past, but we can't predict with certainty what the conditions will be during these months in 2012.

Tornado outbreaks are mainly driven by travelling weather systems (low pressure systems, fronts, and upper-air disturbances) operating on much shorter time scales than El Nino or La Nina. It's whether or not those factors become favorable that ultimately determine whether or not and how bad an outbreak will be. But factors like La Nina can impact the configuration of those travelling weather systems, and thus exert some influence, but aren't the dominant factor.

Another phenomenon that can potentially influence weather patterns is the North Atlantic Oscillation (NAO). An index of this oscillation is positive when there is a strong upper low over or near the Greenland area (as in the figures below). The index is negative when there is relatively high pressure over this region. The nature of the NAO tends to influence the location and intensity of the jet stream pattern over the Northeast, and the temperature pattern over the central and eastern United States.

Positive NAO conditions were present during the record-tornado April 2011. Of the 27 largest and most impactful tornado outbreaks since 1950, 14 were during positive NAO, 8 during negative NAO, and 5 during near-zero periods. Thus, positive NAO tends to favor tornado outbreaks, but it's far from a foolproof indicator. NAO is much more variable and on shorter time scales than El Nino/La Nina, so it can't be predicted far enough in advance to use it in forecasts of tornado activity in 2012.

Another large-scale potential influencing factor is the Arctic Oscillation (AO). This is positive when there is colder-than-average air over the North Pole region at the upper-level jet stream altitudes. Positive NAO tends to mean a stronger-than-average polar jet stream, which can influence possible tornado-producing weather systems. AO was positive during April 2011 and was positive in 16 of the 27 largest and most impactful tornado outbreaks since 1950. Again, though, it is rather variable and can't be predicted far enough in advance to use in forecasts of tornado activity in 2012.

The bottom line is that La Nina conditions may lead to an active January-to-April period for tornadoes in 2012, but that can't be predicted with total certainty. We can all hope that the death toll in 2012 will be way below that of 2011.


View the original article here

Sunday, August 12, 2012

Questions linger for NASCAR following lightning death

LONG POND, Pa. – A long line of cars and campers streamed out of the tunnel at Pocono Raceway past a large American flag that hung at half-mast Monday.

Jeff Gordon leads laps under caution Sunday at Pocono Raceway as a severe thunderstorm approaches. By Jeff Zelevansky, Getty Images

Jeff Gordon leads laps under caution Sunday at Pocono Raceway as a severe thunderstorm approaches.

By Jeff Zelevansky, Getty Images

Jeff Gordon leads laps under caution Sunday at Pocono Raceway as a severe thunderstorm approaches.

In the wake of the multiple lightning strikes after Sunday's Pennsylvania 400 that left a 41-year-old father of two dead and sent nine people to the hospital, many questions surfaced about how NASCAR and its tracks handle inclement weather and its impact on track activity.

Atlanta Motor Speedway President Ed Clark said his track hasn't had to evacuate its 99,000-seat grandstands during a race, but that it would be challenging.

"The tough part — I'm not casting any blame here — is as long as cars are going around (the) track a lot of people aren't going to pay attention to whatever you tell them," Clark told USA TODAY Sports. "That's the difficult thing is what do we do here if you're running the show. I'm not trying to do NASCAR's job. Our job is to manage the facility and take care of the people in the facility. Theirs is to run the race.

"Not knowing what occurred (Sunday), it's hard to make a comment other than the fact that some fans, if there's a car going around the track, they'll sit in a monsoon, and they're going to watch it. That's why we have the greatest fans in the world."

Clark said his 1.5-mile speedway has an emergency plan that is updated each year, and the track works with emergency officials from Henry County during races. An emergency management director is stationed in a control tower booth that is adjacent to NASCAR's control tower.

Clark said it's "hard to say" what would happen if the track decided during a race that there was the potential for unsafe conditions in its grandstands that might necessitate asking NASCAR for a stoppage.

"I've never been in that situation with them," Clark said. "I definitely would go talk to (NASCAR President) Mike Helton and say, 'Here's what we're being told and what to expect.' I'm sure his concern would be like mine, 'Let's take care of the folks that are here.' I'm sure (NASCAR has) some kind of procedure in place, I just don't know what it is because I'm not on that side of the fence."

NASCAR officials said they would comment Monday after Pocono Raceway officials held a 12:45 p.m. news conference to update the situation.

Michigan International Speedway President Roger Curtis said his track has senior staff members next to Helton and other NASCAR executives during the race.

"We've never been in that situation, but if we knew inclement weather is coming, we would talk to NASCAR," Curtis told USA TODAY Sports. "We're going to make a decision based on what's right for fans. We control the grandstands and campgrounds. (NASCAR) controls the on-track activity. Some fans are going to stick around no matter what if they think there's on-track activity.

"If that were to happen at Michigan, we would be in contact with them in the control tower and make a decision about the grandstands, but we would operate independently of (NASCAR) if need be. Hopefully that wouldn't need to happen, it would be simultaneous, but we're there together in the control tower."

Talladega Superspeedway canceled its Saturday activities in 2010 and Friday activities in 2011 because of tornado warnings. Track chairman Grand Lynch said "very few people left" among infield campers despite 17 consecutive hours of tornado warnings in 2010 and 11 straight hours in 2011.

"We send people out to tell fans, but getting them to leave is the hard part," Lynch told USA TODAY Sports. "It's their spot. It's where they like to camp. We even get officers out of the car and have them walk over and talk to them, and (the fans) give you, 'Oh, we've been flooded here before.' "

Lynch said the 2.66-mile track operates a weather command center on site during race weekends that has a staff of 40 including personnel from Talladega and NASCAR. Like Michigan and Atlanta, the track relies on its PA systems, social media networks and portable PA systems on police cars to help spread the word about inclement weather to fans. The tracks also use the SprintVision video boards to provide updates.

Daytona International Speedway has implemented a text messaging system this season to help alert fans with weather updates.

Daytona had a lightning strike on its property on its Sprint Cup race day on July 6, 2002, that sent six people to the hospital, and the track evacuated the grandstands prior to the Pepsi 400. Daytona President Joie Chitwood said there were no serious injuries.

The track also evacuated its grandstands during a practice day in July 2008 but hadn't done so during a race, though Chitwood indicated it would be possible.

"There's an unpredictability that makes it challenging based on the type of threat and where it's coming from and what you do afterward," Chitwood said. "Obviously, fan safety is paramount for us."

It's not uncommon for tracks to cancel and postpone track activity sometimes several hours or even days in advance of race weekends. In September 2003, Dover canceled practice and qualifying Friday two days early because of Hurricane Isabel moving through the East Coast.

Last year, Atlanta moved its race from Sunday night to Tuesday afternoon after a daylong forecast of severe weather for Monday.

"It was the right call for safety; the forecast was for rain and high winds, and we did have tornadoes in metro Atlanta," Clark said. "We'd do the same thing again, even though it upset a lot of fans. You have to make those tough decisions."

In a situation such as Sunday's, Clark said fans would be advised to go to their vehicles.

At Michigan, Curtis tells fans to go "where they think is appropriate. It depends, too, on the type of weather coming, as lightning is much different than tornado. People might be better served under the grandstands or certainly in their cars, if they can get to their cars."

Chitwood said Daytona would tell fans to seek immediate shelter or a place where they feel safe.

"The key is the fan goes to a place where they feel comfortable," he said. '"We don't provide a specific location."

For more information about reprints & permissions, visit our FAQ's. To report corrections and clarifications, contact Standards Editor Brent Jones. For publication consideration in the newspaper, send comments to letters@usatoday.com. Include name, phone number, city and state for verification. To view our corrections, go to corrections.usatoday.com.

View the original article here

Saturday, October 1, 2011

Lightning Delays Washington Monument Rappel (ContributorNetwork)

Engineers began rappelling down the sides of the Washington Monument today as part of an inspection team looking over possible damage to the structure. When the weather forecast turned to possible lightning and thunderstorms in the area, the Associated Press reports the first-of-its-kind operation had to be put on hold.

The obelisk was damaged when a 5.8-magnitude earthquake struck central Virginia in late August 2011. The shaking was felt in Washington and numerous cracks formed on the outer facade of the monument. Although the entire structure is sound and the monument isn't going to collapse, the National Park Service has closed the tourist attraction indefinitely until repairs can be made.

Rain from late summer storms and from Hurricane Irene seeped into the structure through the cracks. The reason for the rappelling team is to ascertain how many cracks are up and down the 555 foot-tall structure. After the initial inspection, teams will begin filling in cracks with caulk to weather proof the building once again. The largest crack is four feet long and an inch wide. Daylight can be seen through some cracks.

Rappelling in less-than-ideal weather conditions can be dangerous. Lightning is a factor because there are lightning rods on the Washington Monument. Even rain can be hazardous as the engineers may slip on the slick marble that is on the outside of the obelisk.

Even dressing appropriately for the weather is also a must. If it gets too cold while a climber is unable to move very quickly, he or she can suffer from hypothermia. Although it won't be as big of deal in warmer months, hypothermia can become a factor if temperatures cool suddenly.

Overly windy conditions may also spell trouble for climbers. Although the ropes are secured at the very top of the Washington Monument, winds can make it difficult for the climbers to stay still and do their work. If they are halfway down the tall structure it may be awhile before they can ascend into the hatch from which they came. The other option is to descend to the bottom to safety on the ground.

Rappelling down the Washington Monument is a once-in-a-lifetime experience that will likely not happen again for another 150 years if at all. All precautions will have to be taken in weird weather so the climbers are safe while they do their jobs.

If all goes well, the Washington Monument will reopen in mid-October.


View the original article here

Tuesday, September 6, 2011

Lightning forces another college football evacuation (Reuters)

CHICAGO (Reuters) – More than 50,000 fans were forced to clear West Virginia University's football stadium on Sunday as severe weather rolled through, the third evacuation this weekend of a college football game because of lightning.

The game in Morgantown, West Virginia, was finally called in the fourth quarter after nearly seven hours of on-again, off-again play, with West Virginia leading in-state rival Marshall 34 to 13.

"Based on the pending weather forecast, as well as the physical and mental fatigue of the student-athletes, it has been decided that the football game between Marshall University and West Virginia University has been stopped in the fourth quarter, resulting in a final score of 34-13," the athletic directors of the two schools said in a statement.

Lightning was seen close by the stadium in the afternoon and the field and stands at Milan Puskar Stadium were cleared with just about five minutes left in the third quarter.

West Virginia was leading Marshall 27 to 13 at the time. The game was halted again early in the fourth quarter.

It was the first lightning delay of a West Virginia home game since 1991, the school said.

On Saturday, lightning strikes forced the University of Michigan and University of Notre Dame to clear their football stadium seats.

Michigan cleared its massive 110,000-seat stadium in Ann Arbor, Michigan, in the third quarter with the team leading Western Michigan 34-10. The teams later agreed to end the game there.

The Notre Dame-South Florida football game was suspended twice. South Florida eventually won 23 to 20.

(Additional reporting by David Bailey; Editing by Greg McCune)


View the original article here

Sunday, June 19, 2011

Floods, lightning kill 8 as heavy rains hit China (AP)

BEIJING – Floods and lightning killed at least eight people as heavy rains pounded southern China, destroying homes and blocking roads, official media said Saturday.

Flooding from this month's seasonal rains has already forced hundreds of thousands of people from their homes and left more than 170 dead or missing.

Two people died in the southern province of Guizhou after being struck by lightning, the official Xinhua News Agency said. Two others died after being washed away by floods Friday evening. Xinhua said four other people died but did not provide details.

The Ministry of Civil Affairs said Friday that flooding and rains have killed 25 people, left 25 missing and forced about 671,200 from their homes since Monday.

Xinhua did not say whether the most recent fatalities were included in the 25.

The torrential rains are forecast to continue through the weekend.

Landslides crushed parts of a railway line in southwestern China on Thursday evening, stranding 5,000 passengers on four trains, railway officials said.

About 1,200 workers are continuing to clear tracks and make repairs along the Chengdu-Kunming railway line, which links the capitals of Sichuan and Yunnan provinces, Xinhua said.


View the original article here

Thursday, June 9, 2011

Officer hit by lightning after Joplin tornado dies (AP)

SPRINGFIELD, Mo. – A Missouri police officer who was struck by lightning while helping with rescues after a massive tornado ripped through Joplin has died.

Riverside Police Chief Greg Mills says 31-year-old officer Jefferson "Jeff" Taylor died Friday at a Springfield hospital, where he had been a patient since he was struck by lightning May 23.

Mills says Taylor was the first Riverside officer to die in the line of duty. He was one of a dozen emergency responders from the Kansas City suburb to volunteer to go to Joplin after the storm that killed more than 130 people.

Mills says Taylor had successful skin graft surgery but was being treated for other complications when he died.

Taylor joined the Riverside department in 2005 and was its Officer of the Year in 2008.


View the original article here