HLSLWX DCZ001-MDZ003>006-011-013-014-016>018-503>508-VAZ052>055-057-505-506-042330- Tropical Storm Isaias Local Statement Advisory Number 30 National Weather Service Baltimore MD/Washington DC AL092020 1123 AM EDT Tue Aug 4 2020 This product covers Eastern West Virginia, Central and Western Maryland, Northern and Northwestern Virginia, and District of Columbia **Tropical Storm Isaias Exiting the Area** NEW INFORMATION --------------- * CHANGES TO WATCHES AND WARNINGS: - The Tropical Storm Warning has been cancelled for Carroll, Central and Southeast Howard, Central and Southeast Montgomery, Northwest Howard, Northwest Montgomery, and Spotsylvania * CURRENT WATCHES AND WARNINGS: - A Tropical Storm Warning is in effect for Anne Arundel, Arlington/Falls Church/Alexandria, Calvert, Charles, District of Columbia, Fairfax, King George, Northern Baltimore, Northwest Harford, Prince Georges, Prince William/Manassas/Manassas Park, Southeast Harford, Southern Baltimore, St. Marys, and Stafford * STORM INFORMATION: - About 30 miles east-southeast of Baltimore MD or about 20 miles east-northeast of Annapolis MD - 39.1N 76.1W - Storm Intensity 70 mph - Movement North-northeast or 20 degrees at 35 mph SITUATION OVERVIEW ------------------ Tropical Storm Isaias is quickly moving away from the area. Tropical Storm force winds and rainfall expected to end over the next couple of hours. Flood and Flash Flood Warnings remain in effect for parts of the area, particularly across central and southern MD. Moderate coastal flooding is still possible along the western shore of the Chesapeake Bay and at Washington DC Southwest Waterfront through this evening. Minor coastal flooding is likely along other tidal waters as well. POTENTIAL IMPACTS ----------------- * FLOODING RAIN: Potential impacts from the flooding rain are still unfolding across all of Maryland east of I-95. Remain well guarded against dangerous flood waters having possible significant impacts. If realized, these impacts include: - Moderate rainfall flooding may prompt several evacuations and rescues. - Rivers and tributaries may quickly become swollen with swifter currents and overspill their banks in a few places, especially in usually vulnerable spots. Small streams, creeks, canals, arroyos, and ditches overflow. - Flood waters can enter some structures or weaken foundations. Several places may experience expanded areas of rapid inundation at underpasses, low-lying spots, and poor drainage areas. Some streets and parking lots take on moving water as storm drains and retention ponds overflow. Driving conditions become hazardous. Some road and bridge closures. * WIND: Potential impacts from the main wind event are now unfolding across southern Maryland. Remain well sheltered from dangerous wind having possible significant impacts. If realized, these impacts include: - Some damage to roofing and siding materials, along with damage to porches, awnings, carports, and sheds. A few buildings experiencing window, door, and garage door failures. Mobile homes damaged, especially if unanchored. Unsecured lightweight objects become dangerous projectiles. - Several large trees snapped or uprooted, but with greater numbers in places where trees are shallow rooted. Several fences and roadway signs blown over. - Some roads impassable from large debris, and more within urban or heavily wooded places. A few bridges, causeways, and access routes impassable. - Scattered power and communications outages, but more prevalent in areas with above ground lines. * SURGE: Potential impacts from the main surge event are now unfolding along the tidal Potomac River and the Chesapeake Bay. Remain well away from locally hazardous surge having additional impacts. If realized, these impacts include: - Localized inundation with storm surge flooding mainly along immediate shorelines and in low-lying spots, or in areas farther inland near where higher surge waters move ashore. - Sections of near-shore roads and parking lots become overspread with surge water. Driving conditions dangerous in places where surge water covers the road. - Moderate beach erosion. Heavy surf also breaching dunes, mainly in usually vulnerable locations. Strong rip currents. - Minor to locally moderate damage to marinas, docks, boardwalks, and piers. A few small craft broken away from moorings. PRECAUTIONARY/PREPAREDNESS ACTIONS ---------------------------------- * PREPAREDNESS INFORMATION: If encountering a flooded roadway, turn around and don`t drown. Most flood deaths occur in vehicles. * ADDITIONAL SOURCES OF INFORMATION: - For information on appropriate preparations see ready.gov - For information on creating an emergency plan see getagameplan.org - For additional disaster preparedness information see redcross.org NEXT UPDATE ----------- The next local statement will be issued by the National Weather Service in Baltimore MD/Washington DC around 230 PM EDT, or sooner if conditions warrant. $$ $$