Moderate

* WHAT...Sub-freezing temperatures as low as 29 expected, especially in outlying areas away from larger bodies of water. * WHERE...Portions of DC, central, northern, and southern Maryland, and central and northern Virginia. * WHEN...From 2 AM to 10 AM EDT Tuesday. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. Take steps now to protect tender plants from the cold. To prevent water pipes from freezing, wrap or drain or allow them to

* WHAT...Sub-freezing temperatures as low as 26 to 30 degrees expected. * WHERE...Portions of central, north central, northeast, and northern Maryland, central, northern, northwest, and western Virginia, and panhandle West Virginia. * WHEN...From 2 AM to 10 AM EDT Tuesday. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. Take steps now to protect tender plants from the cold.

* WHAT...South winds 20 to 30 mph with gusts up to 50 mph expected. * WHERE...Northern Lander and Northern Eureka, Northern Elko, Ruby Mountains and East Humboldt Range in Elko, South Central Elko, Southeastern Elko, and Southwest Elko Counties. * WHEN...From 10 AM to 11 PM PDT Tuesday. * IMPACTS...Gusty winds will blow around unsecured objects. Tree limbs could be blown down and a few power outages may result. Blowing dust may reduce the visibility to one mile or less in spots.

* WHAT...Sub-freezing temperatures as low as 26 expected late tonight and early Tuesday. * WHERE...A portion of central Pennsylvania. * WHEN...From midnight tonight to 9 AM EDT Tuesday. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. Take steps now to protect tender plants and vegetation from the cold. Unprotected early season plantings may freeze.

* WHAT...Sub-freezing temperatures as low as 22 expected late tonight and early Tuesday. * WHERE...Cameron, Clearfield, Elk, McKean, Northern Centre, Northern Clinton, and Warren Counties. * WHEN...From midnight tonight to 11 AM EDT Tuesday. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. Take steps now to protect tender plants and vegetation from the cold. Unprotected early season plantings may freeze.

* WHAT...Sub-freezing temperatures as low as 23 expected. * WHERE...Portions of north central, northeast, and northwest Ohio and northwest Pennsylvania. * WHEN...From 8 PM this evening to 10 AM EDT Tuesday. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. Take steps now to protect tender plants from the cold.

* WHAT...West winds 25 to 35 mph with gusts up to 55 mph expected. * WHERE...Southwest corner of Imperial County. * WHEN...From 3 PM Tuesday to 8 AM PDT Wednesday. * IMPACTS...Difficult driving conditions, especially for larger vehicles traveling along roads with crosswinds. Light, unsecured objects may become airborne. Winds this strong can make driving difficult, especially for high profile vehicles. In addition, strong winds over desert areas could result in briefly

The combination of clear skies, cool and dry air, and light winds will allow temperatures to fall into the mid 30s in sheltered and low lying rural areas. This will be cold enough for patchy frost formation. Those with sensitive vegetation should consider taking precautions tonight.

* WHAT...Blowing snow. Winds gusting as high as 40 mph. * WHERE...Bering Strait Coast and Diomede. * WHEN...Until 10 PM AKDT this evening. * IMPACTS...Travel could be difficult. Areas of blowing snow could significantly reduce visibility to 1/2 mile or less at times. Use caution while traveling, especially in open areas.

* WHAT...Snow and blowing snow. Additional snow accumulations up to one inch. Winds gusting as high as 30 mph. * WHERE...Eastern Norton Sound and Nulato Hills. * WHEN...Until 10 PM AKDT this evening. * IMPACTS...Travel could be difficult. Areas of blowing snow could significantly reduce visibility to 1/2 mile or less at times. Slow down and use caution while traveling.