Everyone knows that Miami sizzles, so when a cold front enveloped South Florida four hours before the start of the inaugural Miami Tropical Marathon in 2003, a 23-year-old Kenyan named David Ruto blazed to victory in 2 hours 12 minutes 22 seconds — still the event record.
Twelve years later, runners could welcome a similar fate, with temperatures forecast to drop more than 10 degrees Saturday night into Sunday for a 6:15 a.m. Miami Marathon and Half Marathon start that should hover in the low 50s. The combined field of more than 20,000 will likely be ecstatic.
“I’m excited for those conditions because it’s the one factor we don’t have control over,’’ said Miami Marathon chief running officer Frankie Ruiz. “I know the locals are thrilled and the out-of-towners will probably be thrilled as well, as it will be warming up enough in the afternoon to go to the beach.’’
Ruiz and race director Javier Sanchez said during a news conference Friday that more than 4,000 participants — at least 21 percent of the registrants — are from outside the country, led by Mexico and Colombia.
Because of the ideal forecast, organizers expect a hefty registration flow at this weekend’s marathon health and fitness expo at the Miami Beach Convention Center.
“One year we had over 2,000 people register at the expo,’’ Ruiz said, noting most of them are half marathoners.
Several elite runners attended a marathon press conference on Friday at the office of Miami-Dade County Mayor Carlos Gimenez. They included former 2009 winner Benazzouz Slimani, a Moroccan who lives in Italy, and 2013 winner Luis Carlos Rivero of Guatemala.
“Miami is one of the best cities I have seen in my life,’’ said Slimani, 40, who left temperatures in the 30s in Northern Italy and is relieved “the weather will be cool and the humidity low.’’ In ’09, Slimani finished in 2:16:49.
Rivero, 28, a lawyer from San Marcos, won the ’13 race in 2:26:14 and placed third last year in 2:30:10. He said he likes “the warmth of the people in Miami.’’
“There are a lot of South Americans here,’’ Rivero said, “so when they see my Guatemala shirt they start cheering for me in Spanish.’’
The event begins outside the AmericanAirlines Arena and proceeds along a scenic route that includes the MacArthur Causeway, Ocean Drive in Miami Beach, the Venetian Causeway, Flagler Street in downtown Miami, Bayshore Drive in Coconut Grove and Brickell Avenue.
The half marathon takes in the first 13.1 miles of the marathon and has a field of speedsters, among them Miamian Bryan Sharkey.
Sharkey, 27, is a senior financial analyst for Carnival Cruise Line. He finished fourth in the Miami Marathon in 2010, but recently finished 73rd in the New York City Marathon in 2:36:55 — the 29th American out of more than 50,000 participants.
Sharkey tore his right hamstring in two places during the NYC race in November, but plans to defend his title at Saturday’s Tropical 5K in Miami Beach before running the half marathon.
“I’m really excited because I’ve run the course two or three times a week for the last year,’’ Sharkey said of the half marathon. “It’s a beautiful course in beautiful weather and a perfect start to the racing season.’’
Miami Marathon and half marathon
▪ When/Where: 6:15 a.m. start (6:05 for wheelchair) Sunday at AmericanAirlines Arena, 601 Biscayne Blvd., Miami.
▪ Who: 25,000 combined field.
▪ Late Registration: $175 marathon; $150 half at expo.
▪ Health and Fitness Expo: 10 a.m. to 6 p.m. Saturday at the Miami Beach Convention Center.
▪ Noteworthy: Tropical 5K in Miami Beach is at 7:30 a.m. Saturday with Watson Island start and Nikki Beach finish (1 Washington Ave.). Cost is $45 through race day.
For information go to www.themiamimarathon.com