The weather data shown above comes from MADIS ( Meteorological Assimilation Data Ingest System ). MADIS collates data from federal, state and local agencies and then makes it available for public use. The MADIS data I use comes primarily from the New Jersey Weather and Climate Network and the Automatic Packet Reporting System ( APRS ). The round icons display current temperatures (°F). When the temperature icon equals or exceeds 90°F it turns red. Temperatures at or below 32°F are shown as blue. These stations range from Ocean City, Maryland to Provincetown, Massachusetts. This map was created primarily to help track the rain / snow line ( the 32°F isotherm ) as winter northeasters move up along the coast. It is also possible to see the cooling effect of sea breezes on coastal sites during the summer. Additional weather data for each station can be accessed in a pop-up table by clicking on the round temperature icons. These data are updated every 10 minutes.