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Land breezes, while as common as sea breezes, are much less frequently experienced. For one thing, they blow offshore, so you might have to be on a boat or an island to feel them at their strongest. For another thing, their strongest isn't all that strong: land breezes are much shallower and weaker than sea breezes. To read about why, go to the optional section on Differences Between Sea Breezes and Land Breezes.
Generally, it's not necessary to worry about land breezes in the WxChallenge. Their effect on temperature and precipitation is minimal. Their biggest impact is offshore, where they may be responsible for the early morning maximum in convection seen offshore along the Gulf coast and the southeastern United States.
A coastal front is a special type of front that is common along the East Coast of the United States, among other places, particularly in late fall and early winter. Coastal fronts are rare in Texas, but when they do occur, weather forecasts are often wildly wrong.
Coastal fronts form when a very cold airmass blows parallel to a coastline or warm nearshore current such as the Gulf Stream. Just like a sea breeze, part of the air is warmed, and a circulation develops with cold air blowing toward warm. Except that it's backward this time: the warm air is over water.
The ideal situation starts out with a northeast wind along the coast, parallel to the coast and to the Gulf Stream. Friction helps by deflecting the flow over land slightly to the left, producing extra convergence along the coast. As the situation evolves, the large-scale winds shift to the east or southeast, but winds over land remain northeasterly as the front intensifies. Although the front may be pushed inland by the strong winds, the cold air gets dammed up and held in place by the Appalachian Mountains. The coastal front persists until the cold air gets blown away.
Temperature contrasts across a coastal front can exceed 10 C, and the front is also a weather producer. Precipitation is enhanced as warm moist air ascends over the dome of cold air, and the precipitation often falls as snow or freezing rain because the cold air can be at or below freezing.
Current numerical weather prediction (NWP) models do not have a high enough resolution to properly forecast sea breezes or land breezes. Since coastal fronts are a bit larger in scale, they are crudely simulated by some NWP models. However, their forecasts should not be taken at face value. In general, the forecast should be modified to reflect the likelihood of a much stronger, more persistent coastal front.
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