* WHAT. Heat index values up to 105. * WHERE. Portions of central, northeast, northern and southern Maryland, The District of Columbia and central and northern Virginia. * WHEN. Until 8 PM EDT this evening. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses to occur.

The Delaware Valley Regional Planning Commission has issued a code orange air quality alert Tuesday for The Philadelphia Metro area. A code orange air quality alert means that air pollution concentrations within the region may become unhealthy for sensitive groups. Sensitive groups include children. people suffering from asthma. heart disease or other lung diseases. and the elderly. The effects of air pollution can be minimized by avoiding strenuous activity or exercise outdoors. For more information on ground-level ozone and fine particles. visit http://www.phila.gov/health/units/ams/

* WHAT. Heat index values up to 107 expected. * WHERE. In Delaware, Kent and Inland Sussex Counties. In Maryland, Caroline, Kent MD, Queen Annes, and Talbot Counties. * WHEN. From 10 AM Tuesday to 8 PM EDT Wednesday. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses.

* WHAT. Heat index values up to 105. * WHERE. Atlantic, Cumberland, and Salem Counties. * WHEN. Until 8 PM EDT Wednesday. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses.

* WHAT. Heat index values up to 104. * WHERE. Portions of northern Delaware, central, northern, and southern New Jersey, and southeast Pennsylvania. * WHEN. Until 8 PM EDT Wednesday. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses.

* WHAT. Heat index values of 105 to 109 expected. * WHERE. In Maryland, Dorchester, Inland Worcester, Somerset, and Wicomico Counties. In Virginia, Northampton and Accomack Counties. * WHEN. From 11 AM to 8 PM EDT Tuesday. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses.

* WHAT. For the first Heat Advisory, heat index values up to 105. For the second Heat Advisory, heat index values up to 107 expected. * WHERE. Portions of central, northeast, northern and southern Maryland, The District of Columbia and central and northern Virginia. * WHEN. For the first Heat Advisory, until 8 PM EDT this evening. For the second Heat Advisory, from noon to 8 PM EDT Tuesday. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses to occur. * ADDITIONAL DETAILS. Overnight conditions will remain warm and humid so continue to find ways to stay cool and hydrated.

* WHAT. Dense fog will reduce visibility to 1 NM or less. * WHERE. Coastal waters from Little Egg Inlet to Great Egg Inlet NJ out 20 nm and Coastal waters from Great Egg Inlet to Cape May NJ out 20 nm. * WHEN. Until 7 PM EDT this evening. * IMPACTS. Low visibility will make navigation difficult.

* WHAT. Dense fog will reduce visibility to 1 NM or less. * WHERE. Delaware Bay waters north of East Point NJ to Slaughter Beach DE and Delaware Bay waters south of East Point NJ to Slaughter Beach DE. * WHEN. Until 7 PM EDT this evening. * IMPACTS. Low visibility will make navigation difficult.

* WHAT. Dense fog will reduce visibility to 1 NM or less. * WHERE. Coastal waters from Cape May NJ to Cape Henlopen DE out 20 nm and Coastal waters from Cape Henlopen to Fenwick Island DE out 20 nm. * WHEN. Until 7 PM EDT this evening. * IMPACTS. Low visibility will make navigation difficult.

The New Jersey Department of Environmental Protection has issued a code orange air quality alert today for much of northern New Jersey and portions of central and southern New Jersey. A code orange air quality alert means that air pollution concentrations within the region may become unhealthy for sensitive groups. Sensitive groups include children. people suffering from asthma. heart disease or other lung diseases. and the elderly. The effects of air pollution can be minimized by avoiding strenuous activity or exercise outdoors. For more information on ground-level ozone and fine particles. visit http://www.state.nj.us/dep/

The Delaware Valley Regional Planning Commission has issued a code orange air quality alert Monday for The Philadelphia Metro area. A code orange air quality alert means that air pollution concentrations within the region may become unhealthy for sensitive groups. Sensitive groups include children. people suffering from asthma. heart disease or other lung diseases. and the elderly. The effects of air pollution can be minimized by avoiding strenuous activity or exercise outdoors. For more information on ground-level ozone and fine particles. visit http://www.phila.gov/health/units/ams/