A leading storm forecaster is sticking with its prediction of a busy Atlantic hurricane season, even with a front over the lower Gulf of Mexico that is already threatening to dump rain across parts of Florida this week.
Colorado State University said Monday that it still expects there to be 18 storms of tropical-storm status or stronger, of which nine would be hurricanes and four major hurricanes, with winds of 111 mph or higher.
Its forecast team issued that prediction in April and affirmed it on the first day of the first full week of hurricane season. Then it went further, putting the chances of a major storm striking the East Coast – including Florida — at 48 percent. The average for the last century is 31 percent.
“The tropical Atlantic remains anomalously warm, and it appears that the chances of an El Niño event this summer and fall are unlikely,” the team’s Phil Klotzbach said. El Niño is a phenomenon of warm water in the Pacific Ocean that tends to hinder the formation of tropical systems.
The historical averages for the Atlantic hurricane season from 1981 through 2010 are 12 tropical storms, 6 ½ hurricanes and two major hurricanes, at Category 3 or higher on the Saffir-Simpson Scale.
The system over the lower Gulf of Mexico, stretching from Mexico’s Yucatan Peninsula to the Florida Straits, has only a 20 percent chance of even becoming a tropical wave, the National Hurricane Center said Monday.
But the system is expected to move to the northeast during the next few days, where it would meet with a weak trough in the upper levels of the atmosphere, so “through at least Thursday we can expect intervals of showers and thunderstorms,” meteorologist Brad Diehl said from the National Weather Service’s Miami office.
“Saying exactly when and where, that’s the issue,” Diehl said. “There’s the potential for heavy rainfall at most any time.”
A May that was one of the wettest on record ended with rainfall of as much as 9 inches in parts of the region last week alone, but a couple of mostly dry days allowed local agencies to bring canals back down to their regulation levels, South Florida Water Management District spokesman Randy Smith said Monday.
With the new rainfall forecast, Smith said, the district started calling around Monday to local drainage districts, cities and counties, suggesting they drop canals even lower.
“We’ve been more aggressive,” Smith said.
Smith said the district is mindful that it could drop levels, then be surprised when rainfall is far less than anticipated.
But, he said, “We have a higher comfort level knowing that it is the wet season, so there’s a chance that if this one doesn’t come, the next one will.”
Since 1995, the tropics have been in a period of more and stronger storms. Such cycles can last 25 to 35 years.
For the first time since records have been kept, the United States has gone seven years without a major hurricane strike, team leader William Gray said Monday.
“These conditions should not be expected to continue,” he said.
In 2012, the Colorado State team predicted 13, five and four at the beginning of the season, tweaking that on Aug. 3 to 14, six and two. The year produced 19, 10 and one. The team will issue a forecast update Aug. 2.
On May 23, the National Oceanic and Atmospheric Administration called for a 70 percent likelihood of 13 to 20 named storms, with seven to 11 of those becoming hurricanes and three to six of those major hurricanes. NOAA also will issue an updated outlook in early August.
Staff writer Sonja Isger contributed to this story.
Colorado State University forecast:
18 named storms
4 major hurricanes
MORE RAIN ON TAP
Tuesday Showers likely; possibly a thunderstorm after 8 a.m. Rain chance 70 percent, 50 percent at night.
Wednesday: Showers likely and possibly a thunderstorm. Rain chance 60 percent day and night.
Thursday Showers and thunderstorms likely. Rain change 60 percent, 50 percent at night. Wind gusts as high as 21 mph.
Friday: 50 percent chance of showers and thunderstorms, 30 percent at night. Wind gusts up to 20 mph.
Saturday: 50 percent chance of showers and thunderstorms, 30 percent at night.
Sunday: 40 percent chance of showers and thunderstorms. Mostly sunny.
SOURCE: National Weather Service Miami office