Chances of a tropical system forming from a broad area of messy weather just east of Nicaragua remained low Tuesday afternoon but could improve as it rolls into the Gulf of Mexico later this week.
National Hurricane Center forecasters, who began tracking the system Monday, said strong upper level winds should keep it from intensifying as it moves westward over Central America and the Yucatan Peninsula over the next two days. Conditions, including warm Gulf waters, could turn more favorable by the end of the week, although chances for formation remain low.
On Tuesday afternoon, forecasters kept the five-day odds for a tropical system at just 20 percent.
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The storm is being steered to the west, northwest, and so far looks like it will head away from Florida. But forecasters warned the wet system is packing heavy rain and could drench parts of flood-prone Central America, including Honduras and Nicaragua.
Forecasters designated the system 91L, making it the first invest (NHC-speak for investigative area) of the official hurricane season. Alberto appeared last month, ahead of the official June 1 start. Alberto, which formed off the Yucatan coast, also churned across the Gulf, but took a more easterly path, spreading heavy rain across much of Florida that broke a century-old rainfall record.
Having systems form over the southern Caribbean so early in the season is not unusual. Warm water can help fuel systems amid waves of tropical moisture.
And while it may look like the Atlantic is off to a brisk start, forecasters are so far calling for a quieter season than 2017, although still above average with 10 to 16 named storms and one to four major hurricanes. Last year, the Atlantic churned out 10 hurricanes in a row, including Harvey, Irma and Maria, which helped make the season the costliest in history.
Forecasters are basing their prediction in part on increasing signs that an El Niño forms in the Pacific, warming waters and increasing hurricane-smothering upper level winds in the Atlantic. Last month, surface water temperatures continued to climb upward, showing no sign of slowing down, University of Miami hurricane researcher Brian McNoldy said in an email. That suggests a weak El Niño could form by midsummer, just in time for the season's historic peak in late August and September.
"Meanwhile, the tropical Atlantic is anomalously cooling, and quite a lot, too," he said. "That also will act to suppress Atlantic hurricane activity if it continues."