The New Jersey Sea Breeze 

and its Relationship to Coastal Upwelling


A research project by Rutgers University's Coastal Ocean Observation Lab 

and the Mount Holly, NJ National Weather Service Forecast Office


Background


The sea breeze is a well-known phenomenon which affects coastal areas primarily during the warm season.  It is driven by the temperature difference between land and sea, which typically peaks during the afternoon hours with maximum diurnal heating of the land.  Effects of the sea breeze include local changes in temperature, humidity, wind speed, wind direction, cloud cover, and sometimes precipitation.  These changes can be significant for operational forecasting of weather conditions for the public, as well as for more specialized users in the aviatrion and marine communities.  

During the Spring and Summer months, the leading edge of the sea breeze is often observed by the National Weather Service's WSR-88D operational radar at Ft. Dix, NJ (KDIX) as a fine line of reflectivity.  Typically, this line forms near the shore in early afternoon and progresses some distance inland during the rest of the day. The shape and movement of this sea breeze "front" can vary considerably from day to day, depending mainly on the degree of heating and on the synoptic scale wind patterns.  

One less recognized factor which may be important in the daily evolution of the sea breeze is the distribution of sea surface temperature along and near the shore. During prolonged periods of southwesterly synoptic-scale flow, it is common to observe the "upwelling" of colder water from below the ocean surface.  This upwelling can produce near-shore pockets of water that are 5 to 10 deg C (or more) colder than the surrounding ocean.  Observational evidence, e.g., radar imagery, suggests that land areads of southwesterly synoptic-scale flow, it is common to observe the "upwelling" of colder water from below the ocean surface.  This upwelling can produce nes adjacent to these cold pockets are favored for the initial development of the sea breeze, and this subsequently affects the movement and orientation of the sea breeze front.