* WHAT. Heat index values up to 101. * WHERE. Morgan County. * WHEN. Until 8 PM EDT this evening. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses to occur.

* WHAT. For the first Heat Advisory, heat index values up to 106. For the second Heat Advisory, heat index values up to 107 expected. * WHERE. Portions of central, north central, northeast, northern and southern Maryland, The District of Columbia and central, northern and northwest Virginia. * WHEN. For the first Heat Advisory, until 8 PM EDT this evening. For the second Heat Advisory, from noon to 8 PM EDT Wednesday. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses to occur.

* WHAT. For the first Heat Advisory, heat index values up to 103. For the second Heat Advisory, heat index values up to 104 expected. * WHERE. In Maryland, Washington County. In Virginia, Rockingham, Shenandoah, Frederick VA, Page, Warren and Clarke Counties. In West Virginia, Berkeley and Jefferson Counties. * WHEN. For the first Heat Advisory, until 8 PM EDT this evening. For the second Heat Advisory, from noon to 8 PM EDT Wednesday. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses to occur.

* WHAT. For the first Heat Advisory, heat index values up to 102. For the second Heat Advisory, heat index values up to 105 expected. * WHERE. In Maryland, Washington County. In Virginia, Rockingham, Shenandoah, Frederick VA, Page, Warren and Clarke Counties. In West Virginia, Berkeley and Jefferson Counties. * WHEN. For the first Heat Advisory, until 8 PM EDT this evening. For the second Heat Advisory, from noon to 8 PM EDT Wednesday. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses to occur.

* WHAT. Heat index values up to 101. * WHERE. Morgan County. * WHEN. Until 8 PM EDT this evening. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses to occur.

* WHAT. For the first Heat Advisory, heat index values up to 108. For the second Heat Advisory, heat index values up to 108 expected. * WHERE. Portions of central, north central, northeast, northern and southern Maryland, The District of Columbia and central, northern and northwest Virginia. * WHEN. For the first Heat Advisory, until 8 PM EDT this evening. For the second Heat Advisory, from noon to 8 PM EDT Wednesday. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses to occur.

* WHAT. For the Excessive Heat Warning, dangerously hot conditions with heat index values up to 110. For the Heat Advisory, heat index values up to 107 expected. * WHERE. Southern Baltimore County. * WHEN. For the Excessive Heat Warning, until 8 PM EDT this evening. For the Heat Advisory, from noon to 8 PM EDT Wednesday. * IMPACTS. Extreme heat and humidity will significantly increase the potential for heat related illnesses, particularly for those working or participating in outdoor activities. * ADDITIONAL DETAILS. Very warm and humid conditions will persist into the overnight hours as well. Ensure to stay hydrated and find ways to stay cool.

* WHAT. For the Excessive Heat Warning, dangerously hot conditions with heat index values up to 110. For the Heat Advisory, heat index values up to 107 expected. * WHERE. Southern Baltimore County. * WHEN. For the Excessive Heat Warning, until 8 PM EDT this evening. For the Heat Advisory, from noon to 8 PM EDT Wednesday. * IMPACTS. Extreme heat and humidity will significantly increase the potential for heat related illnesses, particularly for those working or participating in outdoor activities. * ADDITIONAL DETAILS. Very warm and humid conditions will persist into the overnight hours. Ensure to stay hydrated and find ways to stay cool.

* WHAT. For the first Heat Advisory, heat index values up to 101. For the second Heat Advisory, heat index values up to 104 expected. * WHERE. Morgan County. * WHEN. For the first Heat Advisory, until 8 PM EDT this evening. For the second Heat Advisory, from noon to 8 PM EDT Wednesday. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses to occur. * ADDITIONAL DETAILS. Very warm and humid conditions will persist into the overnight hours. Ensure to stay hydrated and find ways to stay cool.

* WHAT. For the first Heat Advisory, heat index values up to 108. For the second Heat Advisory, heat index values up to 108 expected. * WHERE. Portions of central, north central, northeast, northern and southern Maryland, The District of Columbia and central, northern and northwest Virginia. * WHEN. For the first Heat Advisory, until 8 PM EDT this evening. For the second Heat Advisory, from noon to 8 PM EDT Wednesday. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses to occur. * ADDITIONAL DETAILS. Very warm and humid conditions will persist into the overnight hours. Ensure to stay hydrated and find ways to stay cool.

* WHAT. For the first Heat Advisory, heat index values up to 102. For the second Heat Advisory, heat index values up to 105 expected. * WHERE. In Maryland, Washington County. In Virginia, Rockingham, Shenandoah, Frederick VA, Page, Warren and Clarke Counties. In West Virginia, Berkeley and Jefferson Counties. * WHEN. For the first Heat Advisory, until 8 PM EDT this evening. For the second Heat Advisory, from noon to 8 PM EDT Wednesday. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses to occur. * ADDITIONAL DETAILS. Very warm and humid conditions will persist into the overnight hours. Ensure to stay hydrated and find ways to stay cool.

* WHAT. Oppressive heat with afternoon heat index values between 100 and 105. * WHERE. Adams, Cumberland, Dauphin, Franklin, Lancaster, Lebanon, Perry, and York Counties. * WHEN. Until 8 PM EDT Wednesday. * IMPACTS. High temperatures and humidity may cause heat illnesses.

* WHAT. Oppressive heat with afternoon heat index values between 100 and 105. * WHERE. A portion of South-Central PA and the Lower Susquehanna Valley * WHEN. Until 8 PM EDT Wednesday. * IMPACTS. High temperatures and humidity may cause heat illnesses. * ADDITIONAL DETAILS. In addition to the daytime heat, overnight low temperatures will also be very warm and oppressively muggy.

* WHAT. South winds 10 to 15 kt with gusts up to 25 kt expected. * WHERE. Tidal Potomac River from Key Bridge to Cobb Island MD, Chesapeake Bay north of Pooles Island MD, and Patapsco River including Baltimore Harbor. * WHEN. From 10 AM to 6 PM EDT Wednesday. * IMPACTS. Conditions will be hazardous to small craft.

* WHAT. For the first Small Craft Advisory, south winds 10 to 15 kt with gusts up to 20 kt expected. For the second Small Craft Advisory, south winds 10 to 20 kt with gusts up to 25 kt expected. * WHERE. Chesapeake Bay from Pooles Island MD to Drum Point MD, Tidal Potomac from Cobb Island MD to Smith Point VA, Chester River to Queenstown MD, Eastern Bay, Choptank River to Cambridge MD and the Little Choptank River, and Patuxent River to Broomes Island MD. * WHEN. For the first Small Craft Advisory, until 2 AM EDT Wednesday. For the second Small Craft Advisory, from 10 AM to 6 PM EDT Wednesday. * IMPACTS. Conditions will be hazardous to small craft.

* WHAT. For the Excessive Heat Warning, dangerously hot conditions with heat index values up to 110. For the Heat Advisory, heat index values up to 107 expected. * WHERE. Southern Baltimore County. * WHEN. For the Excessive Heat Warning, until 8 PM EDT this evening. For the Heat Advisory, from noon to 8 PM EDT Wednesday. * IMPACTS. Extreme heat and humidity will significantly increase the potential for heat related illnesses, particularly for those working or participating in outdoor activities. * ADDITIONAL DETAILS. Very warm and humid conditions will persist into the overnight hours. Ensure to stay hydrated and find ways to stay cool.

* WHAT. For the Excessive Heat Warning, dangerously hot conditions with heat index values up to 110. For the Heat Advisory, heat index values up to 107 expected. * WHERE. Portions of central and southern Maryland, The District of Columbia and northern Virginia. * WHEN. For the Excessive Heat Warning, until 8 PM EDT this evening. For the Heat Advisory, from noon to 8 PM EDT Wednesday. * IMPACTS. Extreme heat and humidity will significantly increase the potential for heat related illnesses, particularly for those working or participating in outdoor activities. * ADDITIONAL DETAILS. Very warm and humid conditions will persist into the overnight hours. Ensure to stay hydrated and find ways to stay cool.

* WHAT. For the first Heat Advisory, heat index values up to 108. For the second Heat Advisory, heat index values up to 108 expected. * WHERE. Portions of central, north central, northeast and northern Maryland and central, northern and northwest Virginia. * WHEN. For the first Heat Advisory, until 8 PM EDT this evening. For the second Heat Advisory, from noon to 8 PM EDT Wednesday. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses to occur. * ADDITIONAL DETAILS. Very warm and humid conditions will persist into the overnight hours. Ensure to stay hydrated and find ways to stay cool.

* WHAT. For the first Heat Advisory, heat index values up to 101. For the second Heat Advisory, heat index values up to 104 expected. * WHERE. Morgan County. * WHEN. For the first Heat Advisory, until 8 PM EDT this evening. For the second Heat Advisory, from noon to 8 PM EDT Wednesday. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses to occur. * ADDITIONAL DETAILS. Very warm and humid conditions will persist into the overnight hours. Ensure to stay hydrated and find ways to stay cool.

* WHAT. For the first Heat Advisory, heat index values up to 102. For the second Heat Advisory, heat index values up to 105 expected. * WHERE. In Maryland, Washington County. In Virginia, Rockingham, Shenandoah, Frederick VA, Page, Warren and Clarke Counties. In West Virginia, Berkeley and Jefferson Counties. * WHEN. For the first Heat Advisory, until 8 PM EDT this evening. For the second Heat Advisory, from noon to 8 PM EDT Wednesday. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses to occur. * ADDITIONAL DETAILS. Very warm and humid conditions will persist into the overnight hours. Ensure to stay hydrated and find ways to stay cool.