The second month of the 2013 Atlantic Hurricane season will start quiet, but clues of a more active pattern are starting to show up in the long range forecast models by early next week. Even though upper winds continue to carry copious amounts of tropical moisture across the state, no tropical cyclones are forecast to develop over the next 5 to 10 days that would impact Florida.
The second named storm of the season, Tropical Storm Barry, made landfall in Mexico on June 20th, well ahead of the average date for a second storm, which was August 1st. Barry followed Andrea, a weak Tropical Storm that quickly moved across Florida during the first week of the season. Our next named storm in the Atlantic will be Chantal, but history tells us storm number three doesn’t typically form until the second week of August. Based on the forecast consensus for an active season and some notable shifts in the coming weather patterns, it wouldn’t be surprising to see Chantal by the end of the month.
GULF & CARIBBEAN
Rain, rain, and more rain is currently soaking much of Florida, Cuba, and Central America. This continuous stream of moisture has been in place (and in the forecast) for several days thanks to an unusually deep and strong trough of low pressure over the Gulf of Mexico. This trough will slowly retrograde, or move westward, over the coming days making way for a strengthening ridge of high pressure near Bermuda to take control of the weather pattern across the Southeast US. More typical afternoon thunderstorms will be the result, along with the return of typical summertime heat and humidity. An active stream of weak tropical waves will continue to impact much of the southern Caribbean over the coming days, but strong easterly winds from the aforementioned ridge of high pressure will keep these largely suppressed and under-developed.
As the Bermuda high pressure strengthens early next week, a piece of upper-level energy will likely get caught up in the faster trade winds (that blow east to west) and quickly approach the Bahamas and Florida early next week (on or around July 9-10). At this time, forecast data suggests that upper-level winds will be too strong for anything significant to form near the surface and become tropical. However, the steering currents for this weather feature would bring it across the southern half of Florida and this will be watched closely over the coming days. The rest of the Tropical Atlantic is likely to stay quiet, which is very normal for this time of year. Water temperatures are still just a little too cool in the eastern Atlantic, and wind shear is forecast to remain elevated across the western half of the ocean.
July is typically one of the calmer months of the Atlantic Hurricane Season, usually producing less than one named storm per year on average. The locations where storms are typically born, however, are slightly more expansive. Storms in July commonly develop in the Gulf of Mexico or just offshore of the US East Coast during the first half of the month. Toward the end of the month, it isn’t uncommon for a storm to form in the central or eastern Atlantic, closer to the west coast of Africa. When July storms form in or near the Gulf of Mexico, they typically move toward the Florida panhandle or toward the Texas coastline. Storms that form in the eastern Caribbean or western Atlantic have a slightly higher chance of moving up the east side of the Florida peninsula during the month of July.