The Rain Might Have a Name This Weekend

Newest updates posted above this line. The original story is below.

1. Odds of tropical development increasing this weekend.
2. Regardless, periods of heavy rain expected.
3. Most areas will see more than four inches by Monday.

Heavy rain is coming to most of Florida this weekend. There's no doubt about it. Whether the 3-day deluge has a memorable name is the less important question.

Regardless of potential tropical storm development, a broad area of low pressure will send a copious amount of moisture to Florida during the upcoming holiday weekend. Periods of heavy rain are likely to develop Friday across the southern third of the state. The soggy weather will then spread northward to the rest of the Florida peninsula and panhandle by Saturday. The risk of flooding will grow by Sunday, and the downpours may not wind down until Monday or Tuesday.

Wednesday morning's forecast models were consistent with several prior runs, projecting that more than four inches of rain could fall across a large area of Florida in the next five days, spanning the entire Gulf Coast from Pensacola to Fort Myers. Inland areas of central and south Florida could also receive more than four inches of water by Monday, with slightly lesser amounts (2 to 4 inches) expected elsewhere.The idea that a tropical storm could form in the next few days, more than a week before the official start to the Atlantic hurricane season, is catching a lot of attention on social media. Referred to by meteorologists as Invest 90 (or #90L on Twitter), the disturbance was located near the coast of Belize Wednesday afternoon and reported to be nearly stationary. In a statement Wednesday morning, the National Hurricane Center placed the odds that Invest 90 will acquire or subtropical characteristics at 60 percent.

In the video below, I explain why only marginal conditions exist for truly tropical development over the next few days.

If the disturbance is declared a tropical storm, it would be the first one of the 2018 season and acquire the name Alberto.

Confidence is high in the widespread nature of this weekend's rain event across Florida, but the specifics on where and when the heaviest will fall are still difficult to pin down. How “tropical” in nature Invest 90 becomes may be a moot point, but the track and strength of the low pressure system will play a significant role in which part of Florida receives the repeating downpours.

Most of the Florida peninsula has received well-above normal rainfall this month, and several creeks and streams are already prone to flooding. This is especially true across portions of central Florida, where 5 to 10 inches of rain has fallen in the past two weeks. In a hydrological outlook from the National Weather Service in Melbourne, residents were urged to prepare for “the likelihood of flooding rains later this week and into the weekend.”

Hydrologic Outlook
FLZ041-044>047-053-054-058-059-064-141-144-147-240700-

Hydrologic Outlook
National Weather Service Melbourne FL
314 AM EDT Wed May 23 2018

...Heavy Rain Potential Through the Upcoming Holiday Weekend...

Broad low pressure is forecast to enter the southern Gulf of
Mexico from the Caribbean later this week. Regardless of further
development of this feature, tropical moisture will remain well
established over all of East Central Florida with the potential
for locally heavy showers and occasional storms daily through the
upcoming holiday weekend.

Many areas will see between 3 and 5 inches of rain during this
period, however locally higher amounts are possible. Several days
of localized heavy rain will lead to a continuation of flooding
potential through the weekend.

Many areas of the Treasure Coast to Lake Okeechobee are already
saturated, due to rainfall amounts of 5 to 10 inches over the past
week with some isolated areas greater than a foot since late last
week.

If the forecast rainfall continues as anticipated a Flood Watch
may be needed for portions of East Central Florida. Persons should
be prepared for the likelihood of flooding rains later this week
and into the weekend.

In addition to possible river flooding, which could occur for several days after the event, the rainfall rates may be high enough to warrant a concern for flash flooding. This is the seemingly sudden rise of water in low-lying areas that can flood roads and homes with little notice. Specifics on where and when this risk may come to fruition will be forthcoming in future updates.

The next update from the Florida Public Radio Emergency Network on this developing story will be Thursday morning.