ORLANDO, Fla. \u2014 Central Florida is typically much drier during the winter months, but a strengthening El Nino could change that pattern this season, increasing the potential for heavy rain, severe thunderstorms, damaging winds and even tornadoes.<\/p>\n
The possibility is getting extra attention because two of the deadliest tornado outbreaks in Florida history happened during strong El Nino winters.<\/p>\n
On Feb. 2, 2007, tornadoes tore across Central Florida in the middle of the night during the deadly Groundhog Day outbreak. Twenty-one people were killed in Lake County, including entire families. Victims ranged in age from 7 to 92.<\/p>\n
Just nine years earlier, in February 1998, another devastating tornado outbreak killed 42 people and injured more than 260 across Osceola, Orange, Seminole and Volusia counties.<\/p>\n
Both outbreaks occurred during strong El Nino winters, raising questions about what a potentially powerful El Nino could mean for Florida this season.<\/p>\n
El Nino, Spanish for \u201cthe boy,\u201d develops when ocean temperatures become unusually warm across the central and eastern tropical Pacific.<\/p>\n
Its counterpart, La Nina, or \u201cthe girl,\u201d occurs when those waters are cooler than average.<\/p>\n
These ocean patterns can influence thunderstorms over the Pacific and shift atmospheric wind patterns thousands of miles away, affecting weather across the United States.<\/p>\n
During hurricane season, a strong El Nino typically increases wind shear over the Atlantic, making it more difficult for hurricanes to develop and strengthen. However, it does not eliminate the threat of tropical storms and hurricanes.<\/p>\n
A strong El Nino often strengthens the subtropical jet stream and shifts it farther south. That can direct more storm systems toward Florida during what is normally the state\u2019s dry season.<\/p>\n
More storm systems can mean more opportunities for heavy rainfall, severe thunderstorms and tornadoes.<\/p>\n
For dangerous storms to develop, three key ingredients must come together: moisture, unstable air and changing wind speeds or directions with height, known as wind shear.<\/p>\n
Those ingredients combined during both the deadly 1998 and 2007 tornado outbreaks.<\/p>\n
Does a strong El Nino mean more tornadoes this winter?<\/p>\n
Not necessarily.<\/p>\n
While both historic outbreaks happened during strong El Nino winters, that does not mean the same type of destruction is expected this season.<\/p>\n
A seasonal outlook cannot predict exactly when or where a tornado will develop. It also cannot identify which neighborhoods could be impacted.<\/p>\n
However, the latest NOAA winter rainfall outlook favors an increased chance of above-normal precipitation across the region.<\/p>\n
That does not mean it will rain every day, nor does it specifically forecast tornadoes.<\/p>\n
Instead, the wetter outlook means residents should also pay attention to the potential for repeated rounds of rain, which can increase flooding concerns.<\/p>\n
Strong thunderstorms could also produce damaging winds and other severe weather hazards.<\/p>\n
What about temperatures this winter?<\/p>\n
El Nino winters often trend cooler across parts of the southern United States, but this season\u2019s temperature outlook is more complicated.<\/p>\n
Above-normal rainfall does not automatically mean bitterly cold conditions, and El Nino alone cannot determine whether Central Florida will experience a hard freeze.<\/p>\n
Although forecasters cannot predict exactly when severe weather will strike months in advance, residents can take steps now to be ready.<\/p>\n
Weather technology and warning systems have improved significantly since the devastating tornado outbreaks of 1998 and 2007.<\/p>\n
Meteorologists recommend having more than one way to receive severe weather alerts. That includes enabling emergency alerts on your cellphone and keeping a NOAA Weather Radio that can sound an alarm.<\/p>\n
Residents should also identify a safe place to shelter before severe weather develops.<\/p>\n
The safest location during a tornado is a small, interior room on the lowest floor of a sturdy building, away from windows. Residents should also know where a nearby shelter is located and make sure they can reach it quickly.<\/p>\n
A strong El Nino does not guarantee a dangerous winter for Central Florida. But with the potential for a wetter storm pattern and the state\u2019s history of deadly winter tornado outbreaks, preparedness remains especially important.<\/p>\n
Click here<\/a> to download our free news, weather and smart TV apps. And click here<\/a> to stream Channel 9 Eyewitness News live.<\/p>\n