Critical HLS Hurricane/Tropical Local Statment — Fri Sep 22, 2023 5:38 AM

HLSLWX
MDZ017-018-221730-

Potential Tropical Cyclone Sixteen Local Statement Advisory Number 4
National Weather Service Baltimore MD/Washington DC  AL162023
526 AM EDT Fri Sep 22 2023

This product covers Eastern West Virginia, Central and Western Maryland, Northern and Northwestern Virginia, and District of Columbia

**Tropical Storm Conditions Expected over Southern Maryland Tonight thorugh Early Sunday**

NEW INFORMATION
---------------

* CHANGES TO WATCHES AND WARNINGS:
    - None

* CURRENT WATCHES AND WARNINGS:
    - A Tropical Storm Warning is in effect for Calvert and St. Marys

* STORM INFORMATION:
    - About 590 miles south-southeast of Washington DC
    - 30.5N 75.0W
    - Storm Intensity 50 mph
    - Movement North or 360 degrees at 14 mph

SITUATION OVERVIEW
------------------
Potential Tropical Cyclone Sixteen will move north-northwestward
toward the Mid-Atlantic Coast today before moving northward near the
Mid-Atlantic Coast Saturday through Sunday.

The main threat will be a storm surge with inundation around 2 to
3 feet most likely for locations along the western shore of the
Chesapeake Bay as well as the shore of the tidal Potomac River. The
highest water levels will be around times of high tide Saturday
through Saturday night.

Rainfall will most likely average between 2 to 4 inches with localized
amounts up to 5 inches possible. This may result in isolated instances
of flooding, especially for low lying and flood prone areas. The
heaviest rain is most likely to occur Saturday into Saturday night.

Tropical Storm force winds are most likely over southern Maryland and
the nearby waters south of North Beach along the Chesapeake Bay and
south of Cobb Island along the tidal Potomac River. However,
gale-force winds are expected along the waters father north along the
Chesapeake Bay as well as the tidal Potomac River. Gusty winds and a
saturated ground may cause downed trees and power outages.

While the severe weather threat is low, an isolated tornado cannot out
be ruled across southern Maryland on Saturday afternoon and evening.

POTENTIAL IMPACTS
-----------------

* WIND:
Protect against hazardous wind having possible limited impacts.
Potential impacts in this area include:
    - Damage to porches, awnings, carports, sheds, and unanchored
      mobile homes. Unsecured lightweight objects blown about.
    - Many large tree limbs broken off. A few trees snapped or
      uprooted, but with greater numbers in places where trees are
      shallow rooted. Some fences and roadway signs blown over.
    - A few roads impassable from debris, particularly within urban
      or heavily wooded places. Hazardous driving conditions on
      bridges and other elevated roadways.
    - Scattered power and communications outages.

* SURGE:
Moderate tidal inundation is possible along the shore of the Chesapeake Bay
and tidal Potomac River.
    - 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.

* FLOODING RAIN:
Isolated instances of flooding are possible due to locally heavy
rainfall. The best chance for flooding will be in low lying flood
prone areas as well as urban locations.

    - 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.

Protect against locally hazardous rainfall flooding having possible
limited impacts across southern Maryland.

* TORNADOES:
Protect against a tornado event having possible limited impacts
across southern Maryland. Potential impacts include:
    - The occurrence of isolated tornadoes can hinder the execution
      of emergency plans during tropical events.
    - A few places may experience tornado damage, along with power
      and communications disruptions.
    - Locations could realize roofs peeled off buildings, chimneys
      toppled, mobile homes pushed off foundations or overturned,
      large tree tops and branches snapped off, shallow-rooted trees
      knocked over, moving vehicles blown off roads, and small boats
      pulled from moorings.

PRECAUTIONARY/PREPAREDNESS ACTIONS
----------------------------------

Closely monitor weather.gov. NOAA Weather Radio or local news outlets
for official storm information. Be ready to adapt to possible changes
to the forecast. Ensure you have multiple ways to receive weather
warnings.

* 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 11:15 AM, or sooner if
conditions warrant.

$$