March 20-21 Potential - STORM MODE THREAD in Mid Atlantic Posted March 19, 2018 URGENT - WINTER WEATHER MESSAGE National Weather Service Baltimore MD/Washington DC 342 PM EDT Mon Mar 19 2018 DCZ001-MDZ011-013-014-504-506-VAZ025>027-029-030-040-052>054-501- 506>508-200345- /O.EXB.KLWX.WS.A.0004.180321T0400Z-180322T0000Z/ District of Columbia-Southern Baltimore-Prince Georges- Anne Arundel-Central and Southeast Montgomery- Central and Southeast Howard-Augusta-Rockingham-Shenandoah-Page- Warren-Rappahannock-Prince William/Manassas/Manassas Park-Fairfax- Arlington/Falls Church/Alexandria-Northern Fauquier- Eastern Loudoun-Northern Virginia Blue Ridge- Central Virginia Blue Ridge- 342 PM EDT Mon Mar 19 2018 ...WINTER STORM WATCH IN EFFECT FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY EVENING... * WHAT...Heavy wet snow possible, with a total wet snow accumulation of 5 inches or more. * WHERE...Metropolitan Baltimore and Washington areas, as well as the northern and central Shenandoah Valley. * WHEN...From late Tuesday night through Wednesday evening. * ADDITIONAL DETAILS...Plan on difficult travel conditions. Significant reductions in visibility are possible. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Winter Storm Watch means there is potential for significant snow, sleet or ice accumulations that may impact travel. Continue to monitor the latest forecasts.