MIAMI (CBS4) – Isaac is becoming better organized and a little stronger. A turn toward the northwest in our direction is expected Friday. Isaac will cross Haiti and eastern Cuba tonight and Saturday.

The wind field around Isaac is large and winds will increase over South Florida and the Keys beginning Saturday. Occasional squalls of heavy rain and gusty winds will increase in frequency beginning Friday and continue through Monday night.

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Preparations for tropical storm conditions late Sunday into Monday for mainland South Florida and possible hurricane conditions in the Keys should be underway.

The worst of the weather is expected Sunday through Monday evening with widespread flooding, power outages, wind damage, and isolated tornadoes possible.

This does not look like a shutter event for mainland South Florida. However, if people feel more comfortable putting shutters up, then they should do so on Saturday. We always recommend having a hurricane kit at the beginning of the season and it would be a good idea to top it off before Sunday.

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For boaters, all vessels should be secured with extra docklines and have all sails and windage removed on Saturday. Boats on trailers should be secured with straps to the ground. Boats should not venture out of port Sunday through Monday.

Remember, we talk about the center of Isaac when we show the cone and computer models, but Isaac is a large storm with a broad windfield. The weather will gradually deteriorate through the weekend with the worst weather expected Sunday night into Monday, however squalls with tornadoes, damaging wind gusts, and flooding are possible as early as Saturday night.

>> Visit the CBS4 Tropics Page for an interactive Tropical Tracker, the newest computer model tracks and more.

>> Here’s how to use the CBS4 site to prepare for and monitor Isaac:

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