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Sea Breezes
Sea breezes are a type of mesoscale coastal wind caused by thermal circulation. In the day, the land heats more quickly than the adjacent water causing a shallow thermal low over the land. The air over the water remains relatively cooler giving rise to a shallow thermal high pressure region. The breeze blows from the sea to the land because of the pressure differential. The strongest pressure gradients exist at the land-sea boundary and that is
where the strongest winds form.
During an average summer day in Pensacola, a sea breeze sets up and subsides as follows:
1) By early afternoon (1300 local) the true sea breeze veers and sets in from the SSW (220) at 8-12 knots, increasing to 15-20 knots at max land heating (1400-1600 local). The SW flow continues as the winds gradually decrease as evening cooling occurs.
2) As the land slowly cools to below the surrounding water, the winds initially become light and variable, then calm by 2200 local.
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