The third tropical depression of the season formed in the northeastern Pacific on Sunday afternoon, the National Hurricane Center said. It was forecast to top out as a minimal tropical storm — Calvin — on Tuesday before coming ashore in Mexico. (Credit: NHC)
The drier weather that moved in after last week’s drenching of the Florida peninsula may come to a soggy end late this week and into next weekend, long-term forecasts suggest.
Forecast model scenarios suggesting tropical development are starting to get some attention from the National Weather Service. And Miami forecasters say whatever bubbles up out of the Caribbean next week could bring another period of more concentrated rainfall over the area.
“The GFS and ECMWF both indicate a potential disturbance moving northward in the western Caribbean sometime this weekend,” they said Sunday. “Regardless of its evolution, this feature should advect deeper tropical moisture towards South Florida. If this is the case, expect wetter than normal conditions to return to South Florida.”
Since the models describe scenarios in the seven- to 10-day time frame, there’s plenty of room for debate over the type of system that develops — or whether anything develops at all.
While the eastern half of the Gulf of Mexico had plenty of convection on Sunday, the Caribbean was dead quiet, with the exception of the southern Caribbean off the coast of Central America.
Wind shear maps issued by the University of Wisconsin put the Gulf firmly in the “red zone” — too high for tropical development. Ditto for the northwestern Caribbean.
The Houston National Weather Service office said Sunday morning: “Overall there will be too much shear across the Gulf of Mexico for any tropical development for the next 7 days. While this needs to be filed in that ‘nothing to see here’ category, we will continue to monitor model ‘canes’ that the models are forming in the day 7 to 10 time frame.
“GFS now has some type of system in the Gulf headed towards Tampico Mexico. The ECMWF/CMC develop this same wave over the Yucatan except take the system towards Florida, ECMWF much slower than the CMC. Again, these are model systems in the far extended forecast and usually do not materialize.”
The Atlantic hurricane season runs from June 1 to November 30, but historically June and July are pretty quiet. On average from 1966 to 2009, the first named storm doesn’t form until July 9, and the second doesn’t show up until August 1. The first hurricane normally appears on August 10.
The busiest month for tropical cyclones, based on NOAA data from 1851 to 2015, is September — 578 formed during that month, compared with 383 in August and 118 in July. Only 90 tropical cyclones have formed in June over that 164-year period, according to NOAA.
Last year was quite busy in June, however. There were three named storms — Tropical Storm Bonnie (May 27-June 4); Tropical Storm Colin (June 5-7); and Tropical Storm Danielle (June 19-21). After that impressive run, there wasn’t another named storm in the Atlantic until August 2.
The last June hurricane was Hurricane Chris in 2012. It peaked at 85 mph.