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Drought conditions quickly erased with recent rain

Flood risk could spin back with hurricane season

Heavy rain floods roads on Jacksonville’s Westside
Heavy rain floods roads on Jacksonville’s Westside

Hopefully the only thing to get wiped out this hurricane season is the drought.

The rainy season got an early start in north Florida which typically does not start until June. Florida’s rainy season kicked off in mid to late May, which rounded out the month with above-average rainfall.

The rainy season started early this season in May.
The rainy season started early this season in May. (.)

Recent rain will likely erase the long term dryness over the next few weeks that developed over the spring months.

Counties with the greatest rainfall deficit through May were Putnam, Flagler and St. Johns counties, which have a 12-month rainfall deficit of more than 10 inches.

Flooding has been problematic with 8- to 12-inch totals from Jacksonville’s Westside to areas near I-75 in Columbia and Hamilton counties, yet it could have been worse if it were not so dry initially.

Since it was not wet before the rain, flooding should not last long.

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The hurricane factor

But the upcoming hurricane season may increase the flood risk during the summer.

Rain can be significant with hurricanes especially during the feast or famine months of August through October. It really depends on the hurricane activity.

During 2016-2018 it has been very wet across the southeast from hurricanes but last year dropped off in wetness compared to prior years.

Dr. Gerry Bell, NOAA’s lead seasonal hurricane forecaster, is forecasting a 60% chance for above-normal activity, with 13-19 named storms 6-10 hurricanes 3-6 majors.

If this forecast materializes it would set a record for 5 consecutive above-normal seasons.

Dr. Bell says we have been in a highly active period since 1995. Michael, Florence, Harvey, Irma, Dorian, Maria are all examples of the powerful hurricanes since 2017. During prior years from 1971-1994 saw a slump where average major storms were cut in half 1.5 per season.

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The recent flurry of frequent strong storms are part of a decades-long cycle typically lasting about 25-40 years.

This year the driver for more hurricanes is due to expected weaker shearing winds aloft favoring storm development. Also cool dry conditions in the Pacific called La Nina should keep wind shear low over the Atlantic further bolstering storm activity.

Dr. Bel says there is ”No real chance El Nino will suppress the peak months of hurricane season.”

Various factors are coming together to make for an active hurricane season.
Various factors are coming together to make for an active hurricane season. (NOAA)

Storms not only stronger but closer to hitting the U.S. East coast

Dorian is an example of the close threat of intense super hurricanes. It was only 90 miles away from striking Florida.

In stronger hurricane seasons, storms move closer to the U.S. and strike the east coast more often. These larger hurricanes resist steering patterns that sometimes turn weaker storms away out to sea along the east coast.


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