hurricane dorian briefing - onancocksituation overview hurricane dorian hazard impacts location...

HURRICANE DORIANBRIEFING

www.weather.gov/akq

Wednesday, September 4, 2019

NWSWakefieldVA

6:00 AM EDT

Prepared by: WFO Wakefield, VA

What has changed: Slightly later timing of heavy rainfall and strong winds.

The information contained within is time-sensitive. Do not use after 6:00 PM EDT Wednesday

By 6:00 PM EDT WednesdayNext Briefing:

Disclaimer:

9/4/2019 6:21 AM www.weather.gov/akq

Wakefield, VAWEATHER FORECAST OFFICE

Situation OverviewHurricane Dorian

Hazard Impacts Location Timing

Flooding Rain

Prolonged periods of heavy rainfall could

lead to flash flooding.

Eastern VA and Northeast NC. Thursday night and Friday.

Wind

There is the potential for life threatening

winds/wind damage.

Eastern VA, Northeast NC, and

Southeast MD (Highest threat across

coastal Northeast NC).

Thursday night and Friday.

Storm Surge/

Inundation

While it is still too early for any specific

storm surge values, some locations have

the potential to see moderate to major

tidal flooding.

Anywhere along the coast, but most

likely along lower Chesapeake Bay,

southeast Virginia, and northeast

North Carolina.

Friday into Saturday.

Tornado

Limited to no potential for Tornadoes.

Marine

Very dangerous to extreme marine

conditions are likely.

All coastal waters/nearshore waters,

Chesapeake Bay, Sounds and lower

tidal rivers.

High rip current risk lasting

through the week. Other

marine threats developing

lateThursday into Saturday.



NOTE: Do not focus on the exact track. Impacts can occur well outside the area enclosed by the cone.

Immediate Concerns for the Local Area High risk for rip currents and hazardous seas.

Upcoming Concerns for the Local Area Confidence is high that we will see direct impacts as

early as Thursday afternoon with impacts most likely Thursday night through Friday.

Confidence is increasing with Dorian’s forecast track but changes are still possible.

Key Takeaways Do not focus on the track alone. Impacts will

occur well away from the center.

Now is the time to complete your hurricanepreparedness plans.

Monitor forecasts and seek information from trusted, official sources.

Situation OverviewHurricane Dorian



Threat LevelsHurricane Dorian

Winds SurgeRainfall/

FloodingTornadoes

Incre

asi

ng T

hre

at

For information on specific hazards in this area,

please go to https://www.weather.gov/akq/tropical

Moderate

High

None

Moderate



• A Hurricane Watch remains in

effect for portions of Northeast

North Carolina, including

Elizabeth City.

• A Tropical Storm Watch remains

in effect for much of Eastern

Virginia (including Hampton

Roads) and Northeast North

Carolina.

• A Storm Surge Watch is in effect

for coastal northeast North

Carolina and Hampton Roads

Hazard OverviewHurricane Dorian



The threat for tropical storm force winds

has increased further, especially across

Southeast Virginia and Northeast North

Carolina where they are now likely.

The most likely time of arrival of tropical

storm force winds is Thursday night based

on the current NHC track.

Monitor forecasts and trends with future

updates.

TS Wind Speed ProbabilitiesHurricane Dorian



50 Knot Wind Speed Probabilities

The threat for 50 knot winds has

increased and is highest along the

immediate coastal areas of Southeast VA

and Northeast NC.

Probability of 50 knot winds is likely to

increase as arrival time gets closer.


updates.

Hurricane Dorian



Hurricane Wind Speed Probabilities

The threat for hurricane force winds has

increased slightly along the immediate

coast of Northeast North Carolina.

Probability of hurricane force winds may

increase as arrival time gets closer.


updates.

Hurricane Dorian



The earliest reasonable time of

arrival of Tropical Storm Force Winds

for Northeast NC and Eastern VA is

Thursday afternoon.

However, the most likely time this

area could see Tropical Storm Force

Winds will be late Thursday night into

Friday morning.

Earliest Reasonable Time of Arrival Hurricane Dorian



The most likely time of arrival of

Tropical Storm Force Winds for the

Northeast NC and Eastern VA is

Thursday night into Friday morning.

However, this area could see Tropical

Storm Force Winds as early as

Thursday morning.

Most Likely Time of ArrivalHurricane Dorian



There is a potential for:

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, especially if soils are saturated.

A few roads will be impassable from debris. Hazardous driving conditions on bridges and other elevated roadways.

Scattered power and communication outages can be expected.

Wind Threat / Potential ImpactHurricane Dorian

Wind Threat

Potential for wind greater than 110 mph

Potential for wind 74 to 110 mph



Wind less than 39 mph



Maximum Wind GustsHurricane Dorian

Note:These winds are highly

dependent on storm track.

Based on the expected track,

wind gusts to 60 to 70 mph are

expected along the immediate

coast. Farther inland, gusts of 45

to 55 mph are expected over

eastern Virginia. Gusts of 30-40

MPH are expected along the

Interstate 95 corridor, including

Metro Richmond



Moderate to major flooding coastal

flooding is possible.

Locations of greatest risk:Anywhere

along the coast, but most likely along

lower Chesapeake Bay, southeast Virginia,

and northeast North Carolina.

Timing: Storm surge inundation could

begin as early as Thursday night, with

period of greatest concern coming with

high tide cycle Friday late morning and

afternoon.

Potential Storm Surge FloodingHurricane Dorian

Note: Visit https://water.weather.gov/ahps2/forecasts.php?wfo=akq for the

latest tidal flooding forecasts.

https://water.weather.gov/ahps2/forecasts.php?wfo=akq



Marine Threat PotentialHurricane Dorian

Very dangerous to

extreme marine

conditions are likely

Thursday through

Friday.

Do not focus on

the track alone.

Impacts will occur

well away from the

center.



Confidence is increasing that portions

of Eastern VA and Northeast NC will

see locally heavy rainfall.

Exact amounts will be dependent on

the track and speed of Dorian.

Timing for potential heavy rain is

from Thursday night into Friday.

Potential Storm Total RainfallHurricane Dorian

Note: Confidence is increasing that portions of the area will see locally heavy rainfall.



Storm Total rainfall forecast

valid Thu afternoon through

Friday night.

Locally, most rain will occur

Thursday night into Friday

afternoon, lingering into Friday

night along the coast.

Expected Storm Total RainfallHurricane Dorian

Note: There will likely be locally higher amounts



Excessive Rainfall Outlook

Areas outlined have the

greatest potential for flash

flooding Thursday through

Friday morning.

Excessive Rainfall OutlookHurricane Dorian



There will be a High Rip

Current Risk at area beaches on

Wednesday as large swells from

Dorian arrive.

A High Rip Current Risk is

expected through this week.

Increased Rip Current RiskHurricane Dorian

The latest surf zone forecast can be found at:http://www.weather.gov/beach/akq

http://www.weather.gov/beach/akq



Key Take-AwaysHurricane Dorian

Confidence is HIGH that the event will occur

Confidence is INCREASING regarding exact impacts

In addition to strong rip currents and increasingly rough surf, marine conditions will become very

dangerous to extreme due to increasing waves and the potential for tropical storm or hurricane

force winds Thursday night and Friday.

Prolonged periods of heavy rainfall could lead to flash flooding for portions Eastern VA and Northeast NC.

Tornado potential is low to none based on the current storm track.

There is the potential for surge and tidal flooding, potentially moderate to major in places, late

Thursday through Friday in the Bay and along the coast.

There is the potential for life threatening winds/wind damage across portions of Eastern VA, Northeast

NC, and Southeast MD. The most likely time of arrival is Thursday night into Friday morning based on the

current NHC track.

www.weather.gov/akqNWSWakefieldVA

AKQ Tropical Briefing Webpage: https://www.weather.gov/akq/Tropical

Web: http://weather.gov/akq

Phone: (757) 899-4200

E-mail: [email protected]

Facebook: NWSWakefieldVA

Twitter: NWSWakefieldVA

YouTube: NWSWakefieldVA

Next Briefing:When: By 6:00 PM EDT Wednesday

Method: E-mail

Contact and Next Briefing Information

https://www.weather.gov/akq/Tropical

http://weather.gov/akq

mailto:[email protected]

https://www.facebook.com/NWSWakefieldVA/

https://twitter.com/NWSWakefieldVA

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