Tag Archive | National Weather Service

Flash Flood Watch Issued in Advance of Severe Weather on Friday, April 19

Posted at 3:55 p.m.

Fairfax County is expected to encounter some severe weather throughout the afternoon and evening tomorrow Friday, April 19.  Because of the expected heavy rains, coupled with the strong winds that make flash flooding possible, the National Weather Service (NWS) has issued a Flash Flood Watch from noon Friday until 5 a.m. Saturday morning, April 20.

A Flash Flood Watch means that conditions may develop that lead to flash flooding. Flash flooding is a very dangerous situation. You should monitor weather forecasts and be prepared to take action should Flash Flood Warnings be issued.

Weather Forecast

weather april 18

According to the NWS forecast, the expectation is two primary periods of weather. The first is likely to occur during the late morning and extend into the early afternoon. During this time, isolated thunderstorms will begin in the area and may be strong in nature. Rainfall amounts of a quarter to a half inch are possible during this first round of storms.

The main storm front is expected after 4 p.m., with the most severe weather after 8 p.m. This line of thunderstorms may be severe, with 1.5 to 2 inches of rain possible across the county. The compounding storms may result in as much as 3 inches in some isolated areas, primarily in the northwest of the county.

Along with the rains, these storms will bring high winds of 11 to 15 mph sustained and gusts as high as 30 mph. In addition, some hail is possible.

Turn Around Don’t Drown

If you encounter water on roadways, please remember — Turn Around, Don’t Drown! It is never safe to drive or walk into flood waters.

Turn Around Dont Drown Sign yellowAccording to the Centers for Disease Control and Prevention, over half of all flood-related drownings occur when a vehicle is driven into hazardous flood water. The next highest percentage of flood-related deaths is due to walking into or near flood waters. People underestimate the force and power of water.

Many of the deaths occur in automobiles as they are swept downstream. Of these drownings, many are preventable, but too many people continue to drive around the barriers that warn you the road is flooded.

A mere 6 inches of fast-moving flood water can knock over an adult. It takes just 12 inches of rushing water to carry away a small car, while 2 feet of rushing water can carry away most vehicles.


Fairfax AlertsSign up for severe weather alerts from Fairfax Alerts

Fairfax County’s First Snow of 2019 Expected This Weekend

Posted at 2:30 p.m.

It seems more certain that we’re in for our first snow of 2019 this weekend.

National Weather Service Snow Map January 2019

The National Weather Service forecast for Fairfax County is for 3-4 inches, with snow moving into the area most likely after 1 p.m. Saturday afternoon. Throughout Saturday we should see light snow with about ½” on the ground by nightfall. Temperatures tomorrow will be in the low to mid 30s with calm winds. As the evening progresses, we will begin to see a steadier snowfall with an additional 2-4” overnight. Temperatures will be in the upper 20s with a light wind of 5 mph.

On Sunday, snow continues and will taper off and move out of the area around  by 1 p.m. Temperatures will be in the low to mid 30s with winds of 5-8 mph. There  could be some additional snow showers later Sunday and into the evening, however, no additional accumulation is expected.

In anticipation of the snow, Courtney Arroyo from our Emergency Management Office says in this video that now is a good time to prepare.

Enjoy the first snowfall of the new year … and stay safe if you must venture out! And remember, if you have a police, fire or medical emergency, call (or text) 9-1-1. For non-emergency needs, call 703-691-2131.

Winter Weather Advisory Remains in Effect; County Open, but Facilities and Services May Be Impacted

Winter Weather Advisory

Posted at 8:50 a.m.
Updated at 9:33 a.m.

A Winter Weather Advisory from the National Weather Service remains in effect until 1 p.m. this afternoon (Thursday, Nov. 15). A Winter Weather Advisory means that periods of snow, sleet or freezing rain will cause travel difficulties. Expect slippery roads and limited visibilities, and use caution while driving.

Fairfax County Police are reporting numerous county roadways are impacted by the weather (9 a.m. update). Public safety officials encourage you to use caution and follow police direction.

winter weather Nov. 15, 2018

The National Weather Service (forecast) reports mixed precipitation is expected, with total sleet and snow accumulation of up to one inch, and ice glaze accumulations of up to a tenth of an inch expected. Plan on slippery road and sidewalk conditions in some areas.

County Government Programs Affected

Fairfax County Government is open, however Fairfax County Public Schools are now closed, following an earlier announcement of a two-hour delay. This school closure affects some county programs/services, so please check before you drive to any location to ensure that it is open and operating.

At this time, Fastran has announced that they will transport dialysis, chemotherapy and radiation trips only. All other scheduled route services are canceled, including senior centers, adult day health care, Women’s Recovery Center, senior residence trips and charter services. For general information about Human Services Transportation, call 703-222-9764, TTY 711.

If additional closures or delays are announced by Fairfax County programs, we will announce them via social media and here on the emergency information blog.


Fairfax Alerts

Flood Watch Issued from 2 p.m. Today Through Friday

Posted at 9:45 a.m.

Flood Watch

The National Weather Service has issued a Flood Watch in effect from 2 p.m. this afternoon through Friday evening for the potential for flooding from heavy rain. Localized areas of flooding of small streams and urban areas are possible today and tonight.

A Flood Watch means there is a potential for flooding based on current forecasts. You should monitor later forecasts and be alert for possible Flood Warnings. Those living in areas prone to flooding should be prepared to take action should flooding develop.

From 2 p.m. this afternoon through Friday evening, periods of rain will continue across the region. This rain will be heavy at times, with overall additional rainfall totals of 3 to 5 inches. While flash flooding cannot be ruled out, the primary concern is flooding of small streams and low-lying areas. Streams are already elevated and soils saturated from earlier rainfall, increasing the flood threat.

Turn Around Don’t Drown

Flooding is one of the leading causes of weather related fatalities in the U.S. On average, flooding claims nearly 90 lives each year. More than half of these deaths occur in motor vehicles when people attempt to drive through flooded roadways. This happens because people underestimate the force and power of water, especially when it is moving.

  • Just 6 inches of fast-moving water can knock over and carry off an adult.
  • 12 inches of water can float a small car. If that water is moving, it can carry that car away.
  • 18 to 24 inches of flowing water can carry away most vehicles, including large SUVs.

It is impossible to tell the exact depth of water covering a roadway or the condition of the road below the water. This is especially true at night when your vision is more limited.  It is never safe to drive or walk through flood waters.

Any time you come to a flooded road, walkway, or path, follow this simple rule: Turn Around Don’t Drown.

Enhanced Threat for the Spread of Wild Fires Today, March 15

Posted at 8:30 a.m.

According to the National Weather Service, a combination of gusty winds, low relative humidity and low fuel moisture will enhance the threat for the spread of wildfires late this morning through this afternoon.

Residents are urged to exercise caution handling any potential ignition source, including machinery, cigarettes and matches. Be sure to properly discard all smoking materials. Any dry grasses and tree litter that ignite will have the potential to spread quickly.

More on the forecast from the weather service.