Here's a timeline of what to expect with Idalia in SWFL

Southwest Florida is expected to see tropical storm conditions today as Hurricane Idalia passes parallel to our coast while it gains strength and moves toward the Big Bend.

According to the National Weather Service, the Naples area will soon see winds of around 20 miles per hour out of the southeast as the storm churns over open water.

High tide will be a concern over the next few days as predictions already called for the higher of the two high tides to be about 3.5 feet above normal conditions.

That's one reason the NWS is calling for up to 4 feet of storm surge for the Lee-Collier area.

"That's the inundation you could expect on land as the storm passes," said Ali Davis, a meteorologist with the National Weather Service in Ruskin, which covers most of the west coast of Florida. "That way you don't have to do all the math and look up tides and do all the calculations and math to figure out your risks."

How do you calculate storm surge?

So, you don't add the 3.5 feet high tide mark to the 4-feet of storm surge to get a prediction for your area. That would equate to 7.5 feet of storm surge, which is not what's forecast.

NWS uses a complicated mathematical formula to predict how much water will be on land in coastal areas and lands near rivers and canals.

That means the 4-foot mark is the peak level our area could experience, meaning coastal properties could have up to 4 feet of water on the landscape for a few hours.

The high tide for Matanzas Pass near Fort Myers Beach is at 11:38 a.m. today and 12:37 p.m. Tuesday.

Tuesday afternoon's high tide could bring ocean water onto the landscape as winds are expected to still be blowing around 30 miles per hour and straight onshore, which means water will be pushed inland and into rivers and canals.

A worse-case scenario would have the higher of the two high tides occurring around 4 a.m. Wednesday, when storm conditions are expected to be at their peak here.

As for rain, the outer bands of the storm should start to work their way over Lee and Collier this afternoon, with heavier conditions coming tonight and into early morning Wednesday.

Noon to early afternoon

By noon the Fort Myers and Naples areas will be blanketed with lightning and thunderstorms, which will last for several hours, according to windy.com, which uses a combination of weather forecasts to generate a graphic of future conditions.

Evening effects of Idalia

The heaviest of thunderstorms should be moving out of this area by 9 p.m., but rain will continue until around 7 a.m. Wednesday in both counties.

"By the time we get to this evening, we're going to have the eye parallel to you guys to the west," Davis said. "Then coastal areas will see the higher wind values, and coastal areas could definitely see tropical storm strength winds."

How will winds affect storm surge?

Davis said winds will start to pick up today between 4 p.m. and 6 p.m. and last through the evening hours.

Winds along the coast will likely peak between midnight and 4 a.m., according to windy.com, with Sanibel Island seeing 36 mile per hour winds.

Davis said winds along the coast will stay steady and up to 30 miles per hour through Wednesday as the tail of the storm whips its way over Southwest Florida.

"Probably by the time you get to daybreak, things will slowly start to taper off," she said. "Because of the trajectory, we're going to keep those onshore winds for some time because we're going to see those winds throughout the day tomorrow."

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This article originally appeared on Fort Myers News-Press: Storm conditions will likely improve by daybreak Wednesday