Station Name: DIFFICULT RUN NEAR GREAT FALLS, VA
Data Source: Water Data - usgc.gov

Elevation Above Sea Level: 184 feet

Nearest Address:
9200 Old Dominion Dr
McLean, VA 22102
Fairfax County

GPS Coordinates: 38.97594346, -77.24581439

Nearby Water Temperatures

Winter Storm Warning issued January 23 at 5:16PM EST until January 26 at 4:00AM EST by NWS Baltimore MD/Washington DC

Effective: Fri January 23, 2026, 5:16 PM
Expires: Sat January 24, 2026, 5:30 AM

...MAJOR WINTER STORM WILL IMPACT THE REGION SATURDAY EVENING THROUGH SUNDAY EVENING... .A large area of precipitation will overrun Arctic air in place over the Mid-Atlantic. This will lead to widespread significant snow beginning Saturday evening, with the potential for ice Sunday especially south of Highway 50 and near and east of Interstate 95. In addition to the high threat for significant snow and ice, very cold temperatures are expected tonight through the middle of next week with sub-zero wind chills likely at times. * WHAT...Heavy mixed precipitation expected. Total snow and sleet accumulations between 7 and 14 inches, with highest in the far northern and western suburbs of Washington and Baltimore. Ice accumulations between one and two tenths of an inch. * WHERE...Portions of DC, central, northeast, and northern Maryland, and northern Virginia. * WHEN...From 11 PM Saturday to 4 AM EST Monday. * IMPACTS...Power outages and tree damage are likely due to the ice. Travel could be nearly impossible. The hazardous conditions could impact the Monday morning commute. * ADDITIONAL DETAILS...Snow will likely overspread the area Saturday night, becoming heavy at times with rates of one to two inches per hour possible at times. A mix with sleet or freezing rain is expected Sunday. Significant icing is possible especially south of Highway 50. Visibility of one-quarter mile or less is possible at times. A prolonged period of wind chills in the teens and single digits is likely beginning this evening and lasting through the middle of next week, with sub-zero wind chills possible at times.

If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. The latest road conditions for the state you are calling from can be obtained by calling 5 1 1. Persons should consider delaying all travel. Motorists should use extreme caution if travel is absolutely necessary.

Cold Weather Advisory issued January 23 at 4:08PM EST until January 24 at 10:00AM EST by NWS Baltimore MD/Washington DC

Effective: Fri January 23, 2026, 4:08 PM
Expires: Sat January 24, 2026, 12:15 AM

* WHAT...Very cold wind chills as low as 9 below expected. * WHERE...Portions of DC, central, northeast, and northern Maryland, and central, northern, northwest, and western Virginia. * WHEN...From 8 PM this evening to 10 AM EST Saturday. * IMPACTS...The cold wind chills as low as 10 below zero could result in hypothermia if precautions are not taken. Wind chill values can lead to hypothermia with prolonged exposure.

Use caution while traveling outside. Wear appropriate clothing, a hat, and gloves.

Cold Weather Advisory issued January 23 at 10:27PM EST until January 24 at 10:00AM EST by NWS Baltimore MD/Washington DC

Effective: Fri January 23, 2026, 10:27 PM
Expires: Sat January 24, 2026, 6:30 AM

* WHAT...Very cold wind chills as low as 9 below expected. * WHERE...Portions of DC, central, northeast, and northern Maryland, and central, northern, northwest, and western Virginia. * WHEN...Until 10 AM EST Saturday. * IMPACTS...Wind chill values can lead to hypothermia with prolonged exposure.

Use caution while traveling outside. Wear appropriate clothing, a hat, and gloves.

This is only a test for monitoring of vital dissemination systems.

Effective: Sat January 24, 2026, 1:22 AM
Expires: Sat January 24, 2026, 1:32 AM

Monitoring message only. Please disregard.

Monitoring message only. Please disregard.